Linux patch 5.15.835.15-87

Signed-off-by: Mike Pagano <mpagano@gentoo.org>

2 files changed, 29753 insertions, 0 deletions

diff --git a/0000_README b/0000_README
index 52ff1bed..4db1c439 100644
--- a/0000_README
+++ b/0000_README
@@ -371,6 +371,10 @@ Patch:  1081_linux-5.15.82.patch
 From:   http://www.kernel.org
 Desc:   Linux 5.15.82
 
+Patch:  1082_linux-5.15.83.patch
+From:   http://www.kernel.org
+Desc:   Linux 5.15.83
+
 Patch:  1500_XATTR_USER_PREFIX.patch
 From:   https://bugs.gentoo.org/show_bug.cgi?id=470644
 Desc:   Support for namespace user.pax.* on tmpfs.
diff --git a/1082_linux-5.15.83.patch b/1082_linux-5.15.83.patch
new file mode 100644
index 00000000..19b60bcc
--- /dev/null
+++ b/1082_linux-5.15.83.patch
@@ -0,0 +1,29749 @@
+diff --git a/MAINTAINERS b/MAINTAINERS
+index edc32575828b5..1cf05aee91afc 100644
+--- a/MAINTAINERS
++++ b/MAINTAINERS
+@@ -7244,9 +7244,6 @@ F:	include/linux/fs.h
+ F:	include/linux/fs_types.h
+ F:	include/uapi/linux/fs.h
+ F:	include/uapi/linux/openat2.h
+-X:	fs/io-wq.c
+-X:	fs/io-wq.h
+-X:	fs/io_uring.c
+ 
+ FINTEK F75375S HARDWARE MONITOR AND FAN CONTROLLER DRIVER
+ M:	Riku Voipio <riku.voipio@iki.fi>
+@@ -9818,9 +9815,7 @@ L:	io-uring@vger.kernel.org
+ S:	Maintained
+ T:	git git://git.kernel.dk/linux-block
+ T:	git git://git.kernel.dk/liburing
+-F:	fs/io-wq.c
+-F:	fs/io-wq.h
+-F:	fs/io_uring.c
++F:	io_uring/
+ F:	include/linux/io_uring.h
+ F:	include/uapi/linux/io_uring.h
+ F:	tools/io_uring/
+diff --git a/Makefile b/Makefile
+index bc1cf1200b629..7825a96e9c360 100644
+--- a/Makefile
++++ b/Makefile
+@@ -1,7 +1,7 @@
+ # SPDX-License-Identifier: GPL-2.0
+ VERSION = 5
+ PATCHLEVEL = 15
+-SUBLEVEL = 82
++SUBLEVEL = 83
+ EXTRAVERSION =
+ NAME = Trick or Treat
+ 
+@@ -1150,7 +1150,9 @@ export MODORDER := $(extmod_prefix)modules.order
+ export MODULES_NSDEPS := $(extmod_prefix)modules.nsdeps
+ 
+ ifeq ($(KBUILD_EXTMOD),)
+-core-y		+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/
++core-y			+= kernel/ certs/ mm/ fs/ ipc/ security/ crypto/
++core-$(CONFIG_BLOCK)	+= block/
++core-$(CONFIG_IO_URING)	+= io_uring/
+ 
+ vmlinux-dirs	:= $(patsubst %/,%,$(filter %/, \
+ 		     $(core-y) $(core-m) $(drivers-y) $(drivers-m) \
+diff --git a/arch/arm/boot/dts/imx7s.dtsi b/arch/arm/boot/dts/imx7s.dtsi
+index c8206c636a01f..95f22513a7c02 100644
+--- a/arch/arm/boot/dts/imx7s.dtsi
++++ b/arch/arm/boot/dts/imx7s.dtsi
+@@ -1252,10 +1252,10 @@
+ 			clocks = <&clks IMX7D_NAND_USDHC_BUS_RAWNAND_CLK>;
+ 		};
+ 
+-		gpmi: nand-controller@33002000 {
++		gpmi: nand-controller@33002000{
+ 			compatible = "fsl,imx7d-gpmi-nand";
+ 			#address-cells = <1>;
+-			#size-cells = <0>;
++			#size-cells = <1>;
+ 			reg = <0x33002000 0x2000>, <0x33004000 0x4000>;
+ 			reg-names = "gpmi-nand", "bch";
+ 			interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
+diff --git a/arch/arm/boot/dts/rk3036-evb.dts b/arch/arm/boot/dts/rk3036-evb.dts
+index 2a7e6624efb93..94216f870b57c 100644
+--- a/arch/arm/boot/dts/rk3036-evb.dts
++++ b/arch/arm/boot/dts/rk3036-evb.dts
+@@ -31,11 +31,10 @@
+ &i2c1 {
+ 	status = "okay";
+ 
+-	hym8563: hym8563@51 {
++	hym8563: rtc@51 {
+ 		compatible = "haoyu,hym8563";
+ 		reg = <0x51>;
+ 		#clock-cells = <0>;
+-		clock-frequency = <32768>;
+ 		clock-output-names = "xin32k";
+ 	};
+ };
+diff --git a/arch/arm/boot/dts/rk3188-radxarock.dts b/arch/arm/boot/dts/rk3188-radxarock.dts
+index 36c0945f43b22..3718fac62841c 100644
+--- a/arch/arm/boot/dts/rk3188-radxarock.dts
++++ b/arch/arm/boot/dts/rk3188-radxarock.dts
+@@ -71,7 +71,7 @@
+ 		#sound-dai-cells = <0>;
+ 	};
+ 
+-	ir_recv: gpio-ir-receiver {
++	ir_recv: ir-receiver {
+ 		compatible = "gpio-ir-receiver";
+ 		gpios = <&gpio0 RK_PB2 GPIO_ACTIVE_LOW>;
+ 		pinctrl-names = "default";
+diff --git a/arch/arm/boot/dts/rk3188.dtsi b/arch/arm/boot/dts/rk3188.dtsi
+index 2c606494b78c4..e07b1d79c470a 100644
+--- a/arch/arm/boot/dts/rk3188.dtsi
++++ b/arch/arm/boot/dts/rk3188.dtsi
+@@ -378,7 +378,7 @@
+ 				rockchip,pins = <2 RK_PD3 1 &pcfg_pull_none>;
+ 			};
+ 
+-			lcdc1_rgb24: ldcd1-rgb24 {
++			lcdc1_rgb24: lcdc1-rgb24 {
+ 				rockchip,pins = <2 RK_PA0 1 &pcfg_pull_none>,
+ 						<2 RK_PA1 1 &pcfg_pull_none>,
+ 						<2 RK_PA2 1 &pcfg_pull_none>,
+@@ -606,7 +606,6 @@
+ 
+ &global_timer {
+ 	interrupts = <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(4) | IRQ_TYPE_EDGE_RISING)>;
+-	status = "disabled";
+ };
+ 
+ &local_timer {
+diff --git a/arch/arm/boot/dts/rk3288-evb-act8846.dts b/arch/arm/boot/dts/rk3288-evb-act8846.dts
+index be695b8c1f672..8a635c2431274 100644
+--- a/arch/arm/boot/dts/rk3288-evb-act8846.dts
++++ b/arch/arm/boot/dts/rk3288-evb-act8846.dts
+@@ -54,7 +54,7 @@
+ 		vin-supply = <&vcc_sys>;
+ 	};
+ 
+-	hym8563@51 {
++	rtc@51 {
+ 		compatible = "haoyu,hym8563";
+ 		reg = <0x51>;
+ 
+diff --git a/arch/arm/boot/dts/rk3288-firefly.dtsi b/arch/arm/boot/dts/rk3288-firefly.dtsi
+index 7fb582302b326..74ba7e21850a5 100644
+--- a/arch/arm/boot/dts/rk3288-firefly.dtsi
++++ b/arch/arm/boot/dts/rk3288-firefly.dtsi
+@@ -233,11 +233,10 @@
+ 		vin-supply = <&vcc_sys>;
+ 	};
+ 
+-	hym8563: hym8563@51 {
++	hym8563: rtc@51 {
+ 		compatible = "haoyu,hym8563";
+ 		reg = <0x51>;
+ 		#clock-cells = <0>;
+-		clock-frequency = <32768>;
+ 		clock-output-names = "xin32k";
+ 		interrupt-parent = <&gpio7>;
+ 		interrupts = <RK_PA4 IRQ_TYPE_EDGE_FALLING>;
+diff --git a/arch/arm/boot/dts/rk3288-miqi.dts b/arch/arm/boot/dts/rk3288-miqi.dts
+index 713f55e143c69..db1eb648e0e1a 100644
+--- a/arch/arm/boot/dts/rk3288-miqi.dts
++++ b/arch/arm/boot/dts/rk3288-miqi.dts
+@@ -162,11 +162,10 @@
+ 		vin-supply = <&vcc_sys>;
+ 	};
+ 
+-	hym8563: hym8563@51 {
++	hym8563: rtc@51 {
+ 		compatible = "haoyu,hym8563";
+ 		reg = <0x51>;
+ 		#clock-cells = <0>;
+-		clock-frequency = <32768>;
+ 		clock-output-names = "xin32k";
+ 	};
+ 
+diff --git a/arch/arm/boot/dts/rk3288-rock2-square.dts b/arch/arm/boot/dts/rk3288-rock2-square.dts
+index c4d1d142d8c68..bc44606ca05d8 100644
+--- a/arch/arm/boot/dts/rk3288-rock2-square.dts
++++ b/arch/arm/boot/dts/rk3288-rock2-square.dts
+@@ -165,11 +165,10 @@
+ };
+ 
+ &i2c0 {
+-	hym8563: hym8563@51 {
++	hym8563: rtc@51 {
+ 		compatible = "haoyu,hym8563";
+ 		reg = <0x51>;
+ 		#clock-cells = <0>;
+-		clock-frequency = <32768>;
+ 		clock-output-names = "xin32k";
+ 		interrupt-parent = <&gpio0>;
+ 		interrupts = <RK_PA4 IRQ_TYPE_EDGE_FALLING>;
+diff --git a/arch/arm/boot/dts/rk3288-vmarc-som.dtsi b/arch/arm/boot/dts/rk3288-vmarc-som.dtsi
+index 0ae2bd150e372..793951655b73b 100644
+--- a/arch/arm/boot/dts/rk3288-vmarc-som.dtsi
++++ b/arch/arm/boot/dts/rk3288-vmarc-som.dtsi
+@@ -241,7 +241,6 @@
+ 		interrupt-parent = <&gpio5>;
+ 		interrupts = <RK_PC3 IRQ_TYPE_LEVEL_LOW>;
+ 		#clock-cells = <0>;
+-		clock-frequency = <32768>;
+ 		clock-output-names = "hym8563";
+ 		pinctrl-names = "default";
+ 		pinctrl-0 = <&hym8563_int>;
+diff --git a/arch/arm/boot/dts/rk3xxx.dtsi b/arch/arm/boot/dts/rk3xxx.dtsi
+index 616a828e0c6e4..17e89d30de781 100644
+--- a/arch/arm/boot/dts/rk3xxx.dtsi
++++ b/arch/arm/boot/dts/rk3xxx.dtsi
+@@ -76,6 +76,13 @@
+ 		reg = <0x1013c200 0x20>;
+ 		interrupts = <GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(2) | IRQ_TYPE_EDGE_RISING)>;
+ 		clocks = <&cru CORE_PERI>;
++		status = "disabled";
++		/* The clock source and the sched_clock provided by the arm_global_timer
++		 * on Rockchip rk3066a/rk3188 are quite unstable because their rates
++		 * depend on the CPU frequency.
++		 * Keep the arm_global_timer disabled in order to have the
++		 * DW_APB_TIMER (rk3066a) or ROCKCHIP_TIMER (rk3188) selected by default.
++		 */
+ 	};
+ 
+ 	local_timer: local-timer@1013c600 {
+diff --git a/arch/arm/include/asm/perf_event.h b/arch/arm/include/asm/perf_event.h
+index fe87397c3d8c6..bdbc1e590891e 100644
+--- a/arch/arm/include/asm/perf_event.h
++++ b/arch/arm/include/asm/perf_event.h
+@@ -17,7 +17,7 @@ extern unsigned long perf_misc_flags(struct pt_regs *regs);
+ 
+ #define perf_arch_fetch_caller_regs(regs, __ip) { \
+ 	(regs)->ARM_pc = (__ip); \
+-	(regs)->ARM_fp = (unsigned long) __builtin_frame_address(0); \
++	frame_pointer((regs)) = (unsigned long) __builtin_frame_address(0); \
+ 	(regs)->ARM_sp = current_stack_pointer; \
+ 	(regs)->ARM_cpsr = SVC_MODE; \
+ }
+diff --git a/arch/arm/include/asm/pgtable-nommu.h b/arch/arm/include/asm/pgtable-nommu.h
+index d16aba48fa0a4..090011394477f 100644
+--- a/arch/arm/include/asm/pgtable-nommu.h
++++ b/arch/arm/include/asm/pgtable-nommu.h
+@@ -44,12 +44,6 @@
+ 
+ typedef pte_t *pte_addr_t;
+ 
+-/*
+- * ZERO_PAGE is a global shared page that is always zero: used
+- * for zero-mapped memory areas etc..
+- */
+-#define ZERO_PAGE(vaddr)	(virt_to_page(0))
+-
+ /*
+  * Mark the prot value as uncacheable and unbufferable.
+  */
+diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h
+index cd1f84bb40aea..a25c4303fc0e6 100644
+--- a/arch/arm/include/asm/pgtable.h
++++ b/arch/arm/include/asm/pgtable.h
+@@ -10,6 +10,15 @@
+ #include <linux/const.h>
+ #include <asm/proc-fns.h>
+ 
++#ifndef __ASSEMBLY__
++/*
++ * ZERO_PAGE is a global shared page that is always zero: used
++ * for zero-mapped memory areas etc..
++ */
++extern struct page *empty_zero_page;
++#define ZERO_PAGE(vaddr)	(empty_zero_page)
++#endif
++
+ #ifndef CONFIG_MMU
+ 
+ #include <asm-generic/pgtable-nopud.h>
+@@ -156,13 +165,6 @@ extern pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
+ #define __S111  __PAGE_SHARED_EXEC
+ 
+ #ifndef __ASSEMBLY__
+-/*
+- * ZERO_PAGE is a global shared page that is always zero: used
+- * for zero-mapped memory areas etc..
+- */
+-extern struct page *empty_zero_page;
+-#define ZERO_PAGE(vaddr)	(empty_zero_page)
+-
+ 
+ extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+ 
+diff --git a/arch/arm/mm/nommu.c b/arch/arm/mm/nommu.c
+index 2658f52903da6..88feffebae219 100644
+--- a/arch/arm/mm/nommu.c
++++ b/arch/arm/mm/nommu.c
+@@ -26,6 +26,13 @@
+ 
+ unsigned long vectors_base;
+ 
++/*
++ * empty_zero_page is a special page that is used for
++ * zero-initialized data and COW.
++ */
++struct page *empty_zero_page;
++EXPORT_SYMBOL(empty_zero_page);
++
+ #ifdef CONFIG_ARM_MPU
+ struct mpu_rgn_info mpu_rgn_info;
+ #endif
+@@ -148,9 +155,21 @@ void __init adjust_lowmem_bounds(void)
+  */
+ void __init paging_init(const struct machine_desc *mdesc)
+ {
++	void *zero_page;
++
+ 	early_trap_init((void *)vectors_base);
+ 	mpu_setup();
++
++	/* allocate the zero page. */
++	zero_page = memblock_alloc(PAGE_SIZE, PAGE_SIZE);
++	if (!zero_page)
++		panic("%s: Failed to allocate %lu bytes align=0x%lx\n",
++		      __func__, PAGE_SIZE, PAGE_SIZE);
++
+ 	bootmem_init();
++
++	empty_zero_page = virt_to_page(zero_page);
++	flush_dcache_page(empty_zero_page);
+ }
+ 
+ /*
+diff --git a/arch/arm64/boot/dts/rockchip/rk3308-roc-cc.dts b/arch/arm64/boot/dts/rockchip/rk3308-roc-cc.dts
+index ea6820902ede0..7ea48167747c6 100644
+--- a/arch/arm64/boot/dts/rockchip/rk3308-roc-cc.dts
++++ b/arch/arm64/boot/dts/rockchip/rk3308-roc-cc.dts
+@@ -19,7 +19,7 @@
+ 		stdout-path = "serial2:1500000n8";
+ 	};
+ 
+-	ir_rx {
++	ir-receiver {
+ 		compatible = "gpio-ir-receiver";
+ 		gpios = <&gpio0 RK_PC0 GPIO_ACTIVE_HIGH>;
+ 		pinctrl-names = "default";
+diff --git a/arch/arm64/boot/dts/rockchip/rk3399-rock-pi-4.dtsi b/arch/arm64/boot/dts/rockchip/rk3399-rock-pi-4.dtsi
+index 100a769165ef9..a7ec81657503c 100644
+--- a/arch/arm64/boot/dts/rockchip/rk3399-rock-pi-4.dtsi
++++ b/arch/arm64/boot/dts/rockchip/rk3399-rock-pi-4.dtsi
+@@ -446,7 +446,6 @@
+ &i2s1 {
+ 	rockchip,playback-channels = <2>;
+ 	rockchip,capture-channels = <2>;
+-	status = "okay";
+ };
+ 
+ &i2s2 {
+diff --git a/arch/s390/kvm/vsie.c b/arch/s390/kvm/vsie.c
+index acda4b6fc8518..2c0704f5eb3c6 100644
+--- a/arch/s390/kvm/vsie.c
++++ b/arch/s390/kvm/vsie.c
+@@ -538,8 +538,10 @@ static int shadow_scb(struct kvm_vcpu *vcpu, struct vsie_page *vsie_page)
+ 	if (test_kvm_cpu_feat(vcpu->kvm, KVM_S390_VM_CPU_FEAT_CEI))
+ 		scb_s->eca |= scb_o->eca & ECA_CEI;
+ 	/* Epoch Extension */
+-	if (test_kvm_facility(vcpu->kvm, 139))
++	if (test_kvm_facility(vcpu->kvm, 139)) {
+ 		scb_s->ecd |= scb_o->ecd & ECD_MEF;
++		scb_s->epdx = scb_o->epdx;
++	}
+ 
+ 	/* etoken */
+ 	if (test_kvm_facility(vcpu->kvm, 156))
+diff --git a/block/Makefile b/block/Makefile
+index 41aa1ba69c900..74df168729ecb 100644
+--- a/block/Makefile
++++ b/block/Makefile
+@@ -3,7 +3,7 @@
+ # Makefile for the kernel block layer
+ #
+ 
+-obj-$(CONFIG_BLOCK) := bdev.o fops.o bio.o elevator.o blk-core.o blk-sysfs.o \
++obj-y		:= bdev.o fops.o bio.o elevator.o blk-core.o blk-sysfs.o \
+ 			blk-flush.o blk-settings.o blk-ioc.o blk-map.o \
+ 			blk-exec.o blk-merge.o blk-timeout.o \
+ 			blk-lib.o blk-mq.o blk-mq-tag.o blk-stat.o \
+diff --git a/drivers/bluetooth/btusb.c b/drivers/bluetooth/btusb.c
+index 64d72ea0c3108..69380cb03dd32 100644
+--- a/drivers/bluetooth/btusb.c
++++ b/drivers/bluetooth/btusb.c
+@@ -1901,6 +1901,11 @@ static int btusb_setup_csr(struct hci_dev *hdev)
+ 
+ 	rp = (struct hci_rp_read_local_version *)skb->data;
+ 
++	bt_dev_info(hdev, "CSR: Setting up dongle with HCI ver=%u rev=%04x; LMP ver=%u subver=%04x; manufacturer=%u",
++		le16_to_cpu(rp->hci_ver), le16_to_cpu(rp->hci_rev),
++		le16_to_cpu(rp->lmp_ver), le16_to_cpu(rp->lmp_subver),
++		le16_to_cpu(rp->manufacturer));
++
+ 	/* Detect a wide host of Chinese controllers that aren't CSR.
+ 	 *
+ 	 * Known fake bcdDevices: 0x0100, 0x0134, 0x1915, 0x2520, 0x7558, 0x8891
+diff --git a/drivers/clk/clk-devres.c b/drivers/clk/clk-devres.c
+index f9d5b73343417..4fb4fd4b06bda 100644
+--- a/drivers/clk/clk-devres.c
++++ b/drivers/clk/clk-devres.c
+@@ -4,42 +4,101 @@
+ #include <linux/export.h>
+ #include <linux/gfp.h>
+ 
++struct devm_clk_state {
++	struct clk *clk;
++	void (*exit)(struct clk *clk);
++};
++
+ static void devm_clk_release(struct device *dev, void *res)
+ {
+-	clk_put(*(struct clk **)res);
++	struct devm_clk_state *state = res;
++
++	if (state->exit)
++		state->exit(state->clk);
++
++	clk_put(state->clk);
+ }
+ 
+-struct clk *devm_clk_get(struct device *dev, const char *id)
++static struct clk *__devm_clk_get(struct device *dev, const char *id,
++				  struct clk *(*get)(struct device *dev, const char *id),
++				  int (*init)(struct clk *clk),
++				  void (*exit)(struct clk *clk))
+ {
+-	struct clk **ptr, *clk;
++	struct devm_clk_state *state;
++	struct clk *clk;
++	int ret;
+ 
+-	ptr = devres_alloc(devm_clk_release, sizeof(*ptr), GFP_KERNEL);
+-	if (!ptr)
++	state = devres_alloc(devm_clk_release, sizeof(*state), GFP_KERNEL);
++	if (!state)
+ 		return ERR_PTR(-ENOMEM);
+ 
+-	clk = clk_get(dev, id);
+-	if (!IS_ERR(clk)) {
+-		*ptr = clk;
+-		devres_add(dev, ptr);
+-	} else {
+-		devres_free(ptr);
++	clk = get(dev, id);
++	if (IS_ERR(clk)) {
++		ret = PTR_ERR(clk);
++		goto err_clk_get;
+ 	}
+ 
++	if (init) {
++		ret = init(clk);
++		if (ret)
++			goto err_clk_init;
++	}
++
++	state->clk = clk;
++	state->exit = exit;
++
++	devres_add(dev, state);
++
+ 	return clk;
++
++err_clk_init:
++
++	clk_put(clk);
++err_clk_get:
++
++	devres_free(state);
++	return ERR_PTR(ret);
++}
++
++struct clk *devm_clk_get(struct device *dev, const char *id)
++{
++	return __devm_clk_get(dev, id, clk_get, NULL, NULL);
+ }
+ EXPORT_SYMBOL(devm_clk_get);
+ 
+-struct clk *devm_clk_get_optional(struct device *dev, const char *id)
++struct clk *devm_clk_get_prepared(struct device *dev, const char *id)
+ {
+-	struct clk *clk = devm_clk_get(dev, id);
++	return __devm_clk_get(dev, id, clk_get, clk_prepare, clk_unprepare);
++}
++EXPORT_SYMBOL_GPL(devm_clk_get_prepared);
+ 
+-	if (clk == ERR_PTR(-ENOENT))
+-		return NULL;
++struct clk *devm_clk_get_enabled(struct device *dev, const char *id)
++{
++	return __devm_clk_get(dev, id, clk_get,
++			      clk_prepare_enable, clk_disable_unprepare);
++}
++EXPORT_SYMBOL_GPL(devm_clk_get_enabled);
+ 
+-	return clk;
++struct clk *devm_clk_get_optional(struct device *dev, const char *id)
++{
++	return __devm_clk_get(dev, id, clk_get_optional, NULL, NULL);
+ }
+ EXPORT_SYMBOL(devm_clk_get_optional);
+ 
++struct clk *devm_clk_get_optional_prepared(struct device *dev, const char *id)
++{
++	return __devm_clk_get(dev, id, clk_get_optional,
++			      clk_prepare, clk_unprepare);
++}
++EXPORT_SYMBOL_GPL(devm_clk_get_optional_prepared);
++
++struct clk *devm_clk_get_optional_enabled(struct device *dev, const char *id)
++{
++	return __devm_clk_get(dev, id, clk_get_optional,
++			      clk_prepare_enable, clk_disable_unprepare);
++}
++EXPORT_SYMBOL_GPL(devm_clk_get_optional_enabled);
++
+ struct clk_bulk_devres {
+ 	struct clk_bulk_data *clks;
+ 	int num_clks;
+diff --git a/drivers/gpio/gpio-amd8111.c b/drivers/gpio/gpio-amd8111.c
+index 14e6b3e64add5..6f3ded619c8b2 100644
+--- a/drivers/gpio/gpio-amd8111.c
++++ b/drivers/gpio/gpio-amd8111.c
+@@ -226,7 +226,10 @@ found:
+ 		ioport_unmap(gp.pm);
+ 		goto out;
+ 	}
++	return 0;
++
+ out:
++	pci_dev_put(pdev);
+ 	return err;
+ }
+ 
+@@ -234,6 +237,7 @@ static void __exit amd_gpio_exit(void)
+ {
+ 	gpiochip_remove(&gp.chip);
+ 	ioport_unmap(gp.pm);
++	pci_dev_put(gp.pdev);
+ }
+ 
+ module_init(amd_gpio_init);
+diff --git a/drivers/gpio/gpio-rockchip.c b/drivers/gpio/gpio-rockchip.c
+index d32928c1efe0f..a197f698efebb 100644
+--- a/drivers/gpio/gpio-rockchip.c
++++ b/drivers/gpio/gpio-rockchip.c
+@@ -605,6 +605,7 @@ static int rockchip_gpiolib_register(struct rockchip_pin_bank *bank)
+ 			return -ENODATA;
+ 
+ 		pctldev = of_pinctrl_get(pctlnp);
++		of_node_put(pctlnp);
+ 		if (!pctldev)
+ 			return -ENODEV;
+ 
+diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
+index 320baed949ee8..67bc96403a4e6 100644
+--- a/drivers/gpio/gpiolib.c
++++ b/drivers/gpio/gpiolib.c
+@@ -525,12 +525,13 @@ static int gpiochip_setup_dev(struct gpio_device *gdev)
+ 	if (ret)
+ 		return ret;
+ 
++	/* From this point, the .release() function cleans up gpio_device */
++	gdev->dev.release = gpiodevice_release;
++
+ 	ret = gpiochip_sysfs_register(gdev);
+ 	if (ret)
+ 		goto err_remove_device;
+ 
+-	/* From this point, the .release() function cleans up gpio_device */
+-	gdev->dev.release = gpiodevice_release;
+ 	dev_dbg(&gdev->dev, "registered GPIOs %d to %d on %s\n", gdev->base,
+ 		gdev->base + gdev->ngpio - 1, gdev->chip->label ? : "generic");
+ 
+@@ -594,11 +595,12 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
+ 			       struct lock_class_key *request_key)
+ {
+ 	struct fwnode_handle *fwnode = gc->parent ? dev_fwnode(gc->parent) : NULL;
+-	unsigned long	flags;
+-	int		ret = 0;
+-	unsigned	i;
+-	int		base = gc->base;
+ 	struct gpio_device *gdev;
++	unsigned long flags;
++	unsigned int i;
++	u32 ngpios = 0;
++	int base = 0;
++	int ret = 0;
+ 
+ 	/*
+ 	 * First: allocate and populate the internal stat container, and
+@@ -640,22 +642,43 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
+ 	else
+ 		gdev->owner = THIS_MODULE;
+ 
+-	gdev->descs = kcalloc(gc->ngpio, sizeof(gdev->descs[0]), GFP_KERNEL);
+-	if (!gdev->descs) {
+-		ret = -ENOMEM;
+-		goto err_free_dev_name;
++	/*
++	 * Try the device properties if the driver didn't supply the number
++	 * of GPIO lines.
++	 */
++	ngpios = gc->ngpio;
++	if (ngpios == 0) {
++		ret = device_property_read_u32(&gdev->dev, "ngpios", &ngpios);
++		if (ret == -ENODATA)
++			/*
++			 * -ENODATA means that there is no property found and
++			 * we want to issue the error message to the user.
++			 * Besides that, we want to return different error code
++			 * to state that supplied value is not valid.
++			 */
++			ngpios = 0;
++		else if (ret)
++			goto err_free_dev_name;
++
++		gc->ngpio = ngpios;
+ 	}
+ 
+ 	if (gc->ngpio == 0) {
+ 		chip_err(gc, "tried to insert a GPIO chip with zero lines\n");
+ 		ret = -EINVAL;
+-		goto err_free_descs;
++		goto err_free_dev_name;
+ 	}
+ 
+ 	if (gc->ngpio > FASTPATH_NGPIO)
+ 		chip_warn(gc, "line cnt %u is greater than fast path cnt %u\n",
+ 			  gc->ngpio, FASTPATH_NGPIO);
+ 
++	gdev->descs = kcalloc(gc->ngpio, sizeof(*gdev->descs), GFP_KERNEL);
++	if (!gdev->descs) {
++		ret = -ENOMEM;
++		goto err_free_dev_name;
++	}
++
+ 	gdev->label = kstrdup_const(gc->label ?: "unknown", GFP_KERNEL);
+ 	if (!gdev->label) {
+ 		ret = -ENOMEM;
+@@ -674,11 +697,13 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
+ 	 * it may be a pipe dream. It will not happen before we get rid
+ 	 * of the sysfs interface anyways.
+ 	 */
++	base = gc->base;
+ 	if (base < 0) {
+ 		base = gpiochip_find_base(gc->ngpio);
+ 		if (base < 0) {
+-			ret = base;
+ 			spin_unlock_irqrestore(&gpio_lock, flags);
++			ret = base;
++			base = 0;
+ 			goto err_free_label;
+ 		}
+ 		/*
+@@ -786,6 +811,11 @@ err_remove_of_chip:
+ err_free_gpiochip_mask:
+ 	gpiochip_remove_pin_ranges(gc);
+ 	gpiochip_free_valid_mask(gc);
++	if (gdev->dev.release) {
++		/* release() has been registered by gpiochip_setup_dev() */
++		put_device(&gdev->dev);
++		goto err_print_message;
++	}
+ err_remove_from_list:
+ 	spin_lock_irqsave(&gpio_lock, flags);
+ 	list_del(&gdev->list);
+@@ -799,13 +829,14 @@ err_free_dev_name:
+ err_free_ida:
+ 	ida_free(&gpio_ida, gdev->id);
+ err_free_gdev:
++	kfree(gdev);
++err_print_message:
+ 	/* failures here can mean systems won't boot... */
+ 	if (ret != -EPROBE_DEFER) {
+ 		pr_err("%s: GPIOs %d..%d (%s) failed to register, %d\n", __func__,
+-		       gdev->base, gdev->base + gdev->ngpio - 1,
++		       base, base + (int)ngpios - 1,
+ 		       gc->label ? : "generic", ret);
+ 	}
+-	kfree(gdev);
+ 	return ret;
+ }
+ EXPORT_SYMBOL_GPL(gpiochip_add_data_with_key);
+diff --git a/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c b/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
+index 9014f71d52ddf..f14f7bb3cf0c2 100644
+--- a/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
++++ b/drivers/gpu/drm/amd/amdgpu/sdma_v4_0.c
+@@ -978,13 +978,13 @@ static void sdma_v4_0_ring_emit_fence(struct amdgpu_ring *ring, u64 addr, u64 se
+ 
+ 
+ /**
+- * sdma_v4_0_gfx_stop - stop the gfx async dma engines
++ * sdma_v4_0_gfx_enable - enable the gfx async dma engines
+  *
+  * @adev: amdgpu_device pointer
+- *
+- * Stop the gfx async dma ring buffers (VEGA10).
++ * @enable: enable SDMA RB/IB
++ * control the gfx async dma ring buffers (VEGA10).
+  */
+-static void sdma_v4_0_gfx_stop(struct amdgpu_device *adev)
++static void sdma_v4_0_gfx_enable(struct amdgpu_device *adev, bool enable)
+ {
+ 	struct amdgpu_ring *sdma[AMDGPU_MAX_SDMA_INSTANCES];
+ 	u32 rb_cntl, ib_cntl;
+@@ -999,10 +999,10 @@ static void sdma_v4_0_gfx_stop(struct amdgpu_device *adev)
+ 		}
+ 
+ 		rb_cntl = RREG32_SDMA(i, mmSDMA0_GFX_RB_CNTL);
+-		rb_cntl = REG_SET_FIELD(rb_cntl, SDMA0_GFX_RB_CNTL, RB_ENABLE, 0);
++		rb_cntl = REG_SET_FIELD(rb_cntl, SDMA0_GFX_RB_CNTL, RB_ENABLE, enable ? 1 : 0);
+ 		WREG32_SDMA(i, mmSDMA0_GFX_RB_CNTL, rb_cntl);
+ 		ib_cntl = RREG32_SDMA(i, mmSDMA0_GFX_IB_CNTL);
+-		ib_cntl = REG_SET_FIELD(ib_cntl, SDMA0_GFX_IB_CNTL, IB_ENABLE, 0);
++		ib_cntl = REG_SET_FIELD(ib_cntl, SDMA0_GFX_IB_CNTL, IB_ENABLE, enable ? 1 : 0);
+ 		WREG32_SDMA(i, mmSDMA0_GFX_IB_CNTL, ib_cntl);
+ 	}
+ }
+@@ -1129,7 +1129,7 @@ static void sdma_v4_0_enable(struct amdgpu_device *adev, bool enable)
+ 	int i;
+ 
+ 	if (!enable) {
+-		sdma_v4_0_gfx_stop(adev);
++		sdma_v4_0_gfx_enable(adev, enable);
+ 		sdma_v4_0_rlc_stop(adev);
+ 		if (adev->sdma.has_page_queue)
+ 			sdma_v4_0_page_stop(adev);
+@@ -2063,8 +2063,10 @@ static int sdma_v4_0_suspend(void *handle)
+ 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+ 
+ 	/* SMU saves SDMA state for us */
+-	if (adev->in_s0ix)
++	if (adev->in_s0ix) {
++		sdma_v4_0_gfx_enable(adev, false);
+ 		return 0;
++	}
+ 
+ 	return sdma_v4_0_hw_fini(adev);
+ }
+@@ -2074,8 +2076,12 @@ static int sdma_v4_0_resume(void *handle)
+ 	struct amdgpu_device *adev = (struct amdgpu_device *)handle;
+ 
+ 	/* SMU restores SDMA state for us */
+-	if (adev->in_s0ix)
++	if (adev->in_s0ix) {
++		sdma_v4_0_enable(adev, true);
++		sdma_v4_0_gfx_enable(adev, true);
++		amdgpu_ttm_set_buffer_funcs_status(adev, true);
+ 		return 0;
++	}
+ 
+ 	return sdma_v4_0_hw_init(adev);
+ }
+diff --git a/drivers/gpu/drm/bridge/analogix/anx7625.c b/drivers/gpu/drm/bridge/analogix/anx7625.c
+index 392a9c56e9a00..f895ef1939fa0 100644
+--- a/drivers/gpu/drm/bridge/analogix/anx7625.c
++++ b/drivers/gpu/drm/bridge/analogix/anx7625.c
+@@ -796,7 +796,7 @@ static int sp_tx_edid_read(struct anx7625_data *ctx,
+ 	int count, blocks_num;
+ 	u8 pblock_buf[MAX_DPCD_BUFFER_SIZE];
+ 	u8 i, j;
+-	u8 g_edid_break = 0;
++	int g_edid_break = 0;
+ 	int ret;
+ 	struct device *dev = &ctx->client->dev;
+ 
+@@ -827,7 +827,7 @@ static int sp_tx_edid_read(struct anx7625_data *ctx,
+ 				g_edid_break = edid_read(ctx, offset,
+ 							 pblock_buf);
+ 
+-				if (g_edid_break)
++				if (g_edid_break < 0)
+ 					break;
+ 
+ 				memcpy(&pedid_blocks_buf[offset],
+diff --git a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+index d3129a3e6ab76..8bb403bc712a4 100644
+--- a/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
++++ b/drivers/gpu/drm/bridge/synopsys/dw-hdmi.c
+@@ -2594,6 +2594,9 @@ static u32 *dw_hdmi_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
+ 	 * if supported. In any case the default RGB888 format is added
+ 	 */
+ 
++	/* Default 8bit RGB fallback */
++	output_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
++
+ 	if (max_bpc >= 16 && info->bpc == 16) {
+ 		if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444)
+ 			output_fmts[i++] = MEDIA_BUS_FMT_YUV16_1X48;
+@@ -2627,9 +2630,6 @@ static u32 *dw_hdmi_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
+ 	if (info->color_formats & DRM_COLOR_FORMAT_YCRCB444)
+ 		output_fmts[i++] = MEDIA_BUS_FMT_YUV8_1X24;
+ 
+-	/* Default 8bit RGB fallback */
+-	output_fmts[i++] = MEDIA_BUS_FMT_RGB888_1X24;
+-
+ 	*num_output_fmts = i;
+ 
+ 	return output_fmts;
+diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
+index 45a5f1e48f0ef..bbedce0eeddae 100644
+--- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c
++++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c
+@@ -920,9 +920,9 @@ static void ti_sn_bridge_set_video_timings(struct ti_sn65dsi86 *pdata)
+ 		&pdata->bridge.encoder->crtc->state->adjusted_mode;
+ 	u8 hsync_polarity = 0, vsync_polarity = 0;
+ 
+-	if (mode->flags & DRM_MODE_FLAG_PHSYNC)
++	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
+ 		hsync_polarity = CHA_HSYNC_POLARITY;
+-	if (mode->flags & DRM_MODE_FLAG_PVSYNC)
++	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
+ 		vsync_polarity = CHA_VSYNC_POLARITY;
+ 
+ 	ti_sn65dsi86_write_u16(pdata, SN_CHA_ACTIVE_LINE_LENGTH_LOW_REG,
+diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c
+index a30ffc07470cc..15c3849e995bd 100644
+--- a/drivers/gpu/drm/drm_gem_shmem_helper.c
++++ b/drivers/gpu/drm/drm_gem_shmem_helper.c
+@@ -541,12 +541,20 @@ static void drm_gem_shmem_vm_open(struct vm_area_struct *vma)
+ {
+ 	struct drm_gem_object *obj = vma->vm_private_data;
+ 	struct drm_gem_shmem_object *shmem = to_drm_gem_shmem_obj(obj);
+-	int ret;
+ 
+ 	WARN_ON(shmem->base.import_attach);
+ 
+-	ret = drm_gem_shmem_get_pages(shmem);
+-	WARN_ON_ONCE(ret != 0);
++	mutex_lock(&shmem->pages_lock);
++
++	/*
++	 * We should have already pinned the pages when the buffer was first
++	 * mmap'd, vm_open() just grabs an additional reference for the new
++	 * mm the vma is getting copied into (ie. on fork()).
++	 */
++	if (!WARN_ON_ONCE(!shmem->pages_use_count))
++		shmem->pages_use_count++;
++
++	mutex_unlock(&shmem->pages_lock);
+ 
+ 	drm_gem_vm_open(vma);
+ }
+@@ -591,10 +599,8 @@ int drm_gem_shmem_mmap(struct drm_gem_shmem_object *shmem, struct vm_area_struct
+ 	}
+ 
+ 	ret = drm_gem_shmem_get_pages(shmem);
+-	if (ret) {
+-		drm_gem_vm_close(vma);
++	if (ret)
+ 		return ret;
+-	}
+ 
+ 	vma->vm_flags |= VM_MIXEDMAP | VM_DONTEXPAND;
+ 	vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
+diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
+index 47eb3a50dd08e..8d2437fa6894b 100644
+--- a/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
++++ b/drivers/gpu/drm/vmwgfx/vmwgfx_msg.c
+@@ -1085,21 +1085,21 @@ int vmw_mksstat_add_ioctl(struct drm_device *dev, void *data,
+ 	reset_ppn_array(pdesc->strsPPNs, ARRAY_SIZE(pdesc->strsPPNs));
+ 
+ 	/* Pin mksGuestStat user pages and store those in the instance descriptor */
+-	nr_pinned_stat = pin_user_pages(arg->stat, num_pages_stat, FOLL_LONGTERM, pages_stat, NULL);
++	nr_pinned_stat = pin_user_pages_fast(arg->stat, num_pages_stat, FOLL_LONGTERM, pages_stat);
+ 	if (num_pages_stat != nr_pinned_stat)
+ 		goto err_pin_stat;
+ 
+ 	for (i = 0; i < num_pages_stat; ++i)
+ 		pdesc->statPPNs[i] = page_to_pfn(pages_stat[i]);
+ 
+-	nr_pinned_info = pin_user_pages(arg->info, num_pages_info, FOLL_LONGTERM, pages_info, NULL);
++	nr_pinned_info = pin_user_pages_fast(arg->info, num_pages_info, FOLL_LONGTERM, pages_info);
+ 	if (num_pages_info != nr_pinned_info)
+ 		goto err_pin_info;
+ 
+ 	for (i = 0; i < num_pages_info; ++i)
+ 		pdesc->infoPPNs[i] = page_to_pfn(pages_info[i]);
+ 
+-	nr_pinned_strs = pin_user_pages(arg->strs, num_pages_strs, FOLL_LONGTERM, pages_strs, NULL);
++	nr_pinned_strs = pin_user_pages_fast(arg->strs, num_pages_strs, FOLL_LONGTERM, pages_strs);
+ 	if (num_pages_strs != nr_pinned_strs)
+ 		goto err_pin_strs;
+ 
+diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_scrn.c b/drivers/gpu/drm/vmwgfx/vmwgfx_scrn.c
+index bd157fb21b450..605ff05d449fc 100644
+--- a/drivers/gpu/drm/vmwgfx/vmwgfx_scrn.c
++++ b/drivers/gpu/drm/vmwgfx/vmwgfx_scrn.c
+@@ -953,6 +953,10 @@ int vmw_kms_sou_init_display(struct vmw_private *dev_priv)
+ 	struct drm_device *dev = &dev_priv->drm;
+ 	int i, ret;
+ 
++	/* Screen objects won't work if GMR's aren't available */
++	if (!dev_priv->has_gmr)
++		return -ENOSYS;
++
+ 	if (!(dev_priv->capabilities & SVGA_CAP_SCREEN_OBJECT_2)) {
+ 		return -ENOSYS;
+ 	}
+diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
+index dbed2524fd47b..ef9c799fa3715 100644
+--- a/drivers/hid/hid-core.c
++++ b/drivers/hid/hid-core.c
+@@ -1310,6 +1310,9 @@ static s32 snto32(__u32 value, unsigned n)
+ 	if (!value || !n)
+ 		return 0;
+ 
++	if (n > 32)
++		n = 32;
++
+ 	switch (n) {
+ 	case 8:  return ((__s8)value);
+ 	case 16: return ((__s16)value);
+diff --git a/drivers/hid/hid-ids.h b/drivers/hid/hid-ids.h
+index c8a313c84a57d..78b55f845d2d4 100644
+--- a/drivers/hid/hid-ids.h
++++ b/drivers/hid/hid-ids.h
+@@ -261,6 +261,7 @@
+ #define USB_DEVICE_ID_CH_AXIS_295	0x001c
+ 
+ #define USB_VENDOR_ID_CHERRY		0x046a
++#define USB_DEVICE_ID_CHERRY_MOUSE_000C	0x000c
+ #define USB_DEVICE_ID_CHERRY_CYMOTION	0x0023
+ #define USB_DEVICE_ID_CHERRY_CYMOTION_SOLAR	0x0027
+ 
+@@ -892,6 +893,7 @@
+ #define USB_DEVICE_ID_MS_XBOX_ONE_S_CONTROLLER	0x02fd
+ #define USB_DEVICE_ID_MS_PIXART_MOUSE    0x00cb
+ #define USB_DEVICE_ID_8BITDO_SN30_PRO_PLUS      0x02e0
++#define USB_DEVICE_ID_MS_MOUSE_0783      0x0783
+ 
+ #define USB_VENDOR_ID_MOJO		0x8282
+ #define USB_DEVICE_ID_RETRO_ADAPTER	0x3201
+@@ -1182,6 +1184,7 @@
+ #define USB_DEVICE_ID_SYNAPTICS_DELL_K15A	0x6e21
+ #define USB_DEVICE_ID_SYNAPTICS_ACER_ONE_S1002	0x73f4
+ #define USB_DEVICE_ID_SYNAPTICS_ACER_ONE_S1003	0x73f5
++#define USB_DEVICE_ID_SYNAPTICS_ACER_SWITCH5_017	0x73f6
+ #define USB_DEVICE_ID_SYNAPTICS_ACER_SWITCH5	0x81a7
+ 
+ #define USB_VENDOR_ID_TEXAS_INSTRUMENTS	0x2047
+@@ -1338,6 +1341,7 @@
+ 
+ #define USB_VENDOR_ID_PRIMAX	0x0461
+ #define USB_DEVICE_ID_PRIMAX_MOUSE_4D22	0x4d22
++#define USB_DEVICE_ID_PRIMAX_MOUSE_4E2A	0x4e2a
+ #define USB_DEVICE_ID_PRIMAX_KEYBOARD	0x4e05
+ #define USB_DEVICE_ID_PRIMAX_REZEL	0x4e72
+ #define USB_DEVICE_ID_PRIMAX_PIXART_MOUSE_4D0F	0x4d0f
+diff --git a/drivers/hid/hid-ite.c b/drivers/hid/hid-ite.c
+index 430fa4f52ed3b..75ebfcf318896 100644
+--- a/drivers/hid/hid-ite.c
++++ b/drivers/hid/hid-ite.c
+@@ -121,6 +121,11 @@ static const struct hid_device_id ite_devices[] = {
+ 		     USB_VENDOR_ID_SYNAPTICS,
+ 		     USB_DEVICE_ID_SYNAPTICS_ACER_ONE_S1003),
+ 	  .driver_data = QUIRK_TOUCHPAD_ON_OFF_REPORT },
++	/* ITE8910 USB kbd ctlr, with Synaptics touchpad connected to it. */
++	{ HID_DEVICE(BUS_USB, HID_GROUP_GENERIC,
++		     USB_VENDOR_ID_SYNAPTICS,
++		     USB_DEVICE_ID_SYNAPTICS_ACER_SWITCH5_017),
++	  .driver_data = QUIRK_TOUCHPAD_ON_OFF_REPORT },
+ 	{ }
+ };
+ MODULE_DEVICE_TABLE(hid, ite_devices);
+diff --git a/drivers/hid/hid-lg4ff.c b/drivers/hid/hid-lg4ff.c
+index 5e6a0cef2a06d..e3fcf1353fb3b 100644
+--- a/drivers/hid/hid-lg4ff.c
++++ b/drivers/hid/hid-lg4ff.c
+@@ -872,6 +872,12 @@ static ssize_t lg4ff_alternate_modes_store(struct device *dev, struct device_att
+ 		return -ENOMEM;
+ 
+ 	i = strlen(lbuf);
++
++	if (i == 0) {
++		kfree(lbuf);
++		return -EINVAL;
++	}
++
+ 	if (lbuf[i-1] == '\n') {
+ 		if (i == 1) {
+ 			kfree(lbuf);
+diff --git a/drivers/hid/hid-quirks.c b/drivers/hid/hid-quirks.c
+index 8d36cb7551cf1..fc1e061900bc0 100644
+--- a/drivers/hid/hid-quirks.c
++++ b/drivers/hid/hid-quirks.c
+@@ -54,6 +54,7 @@ static const struct hid_device_id hid_quirks[] = {
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_CH, USB_DEVICE_ID_CH_FLIGHT_SIM_YOKE), HID_QUIRK_NOGET },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_CH, USB_DEVICE_ID_CH_PRO_PEDALS), HID_QUIRK_NOGET },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_CH, USB_DEVICE_ID_CH_PRO_THROTTLE), HID_QUIRK_NOGET },
++	{ HID_USB_DEVICE(USB_VENDOR_ID_CHERRY, USB_DEVICE_ID_CHERRY_MOUSE_000C), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_CORSAIR, USB_DEVICE_ID_CORSAIR_K65RGB), HID_QUIRK_NO_INIT_REPORTS },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_CORSAIR, USB_DEVICE_ID_CORSAIR_K65RGB_RAPIDFIRE), HID_QUIRK_NO_INIT_REPORTS | HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_CORSAIR, USB_DEVICE_ID_CORSAIR_K70RGB), HID_QUIRK_NO_INIT_REPORTS },
+@@ -122,6 +123,7 @@ static const struct hid_device_id hid_quirks[] = {
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_MOUSE_C05A), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_LOGITECH, USB_DEVICE_ID_LOGITECH_MOUSE_C06A), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_MCS, USB_DEVICE_ID_MCS_GAMEPADBLOCK), HID_QUIRK_MULTI_INPUT },
++	{ HID_USB_DEVICE(USB_VENDOR_ID_MICROSOFT, USB_DEVICE_ID_MS_MOUSE_0783), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_MICROSOFT, USB_DEVICE_ID_MS_PIXART_MOUSE), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_MICROSOFT, USB_DEVICE_ID_MS_POWER_COVER), HID_QUIRK_NO_INIT_REPORTS },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_MICROSOFT, USB_DEVICE_ID_MS_SURFACE3_COVER), HID_QUIRK_NO_INIT_REPORTS },
+@@ -146,6 +148,7 @@ static const struct hid_device_id hid_quirks[] = {
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_PIXART, USB_DEVICE_ID_PIXART_OPTICAL_TOUCH_SCREEN), HID_QUIRK_NO_INIT_REPORTS },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_PIXART, USB_DEVICE_ID_PIXART_USB_OPTICAL_MOUSE), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_MOUSE_4D22), HID_QUIRK_ALWAYS_POLL },
++	{ HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_MOUSE_4E2A), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_PIXART_MOUSE_4D0F), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_PIXART_MOUSE_4D65), HID_QUIRK_ALWAYS_POLL },
+ 	{ HID_USB_DEVICE(USB_VENDOR_ID_PRIMAX, USB_DEVICE_ID_PRIMAX_PIXART_MOUSE_4E22), HID_QUIRK_ALWAYS_POLL },
+diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
+index 033b0c83272fe..30c8497f7c118 100644
+--- a/drivers/media/common/videobuf2/videobuf2-core.c
++++ b/drivers/media/common/videobuf2/videobuf2-core.c
+@@ -788,7 +788,13 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
+ 	num_buffers = max_t(unsigned int, *count, q->min_buffers_needed);
+ 	num_buffers = min_t(unsigned int, num_buffers, VB2_MAX_FRAME);
+ 	memset(q->alloc_devs, 0, sizeof(q->alloc_devs));
++	/*
++	 * Set this now to ensure that drivers see the correct q->memory value
++	 * in the queue_setup op.
++	 */
++	mutex_lock(&q->mmap_lock);
+ 	q->memory = memory;
++	mutex_unlock(&q->mmap_lock);
+ 
+ 	/*
+ 	 * Ask the driver how many buffers and planes per buffer it requires.
+@@ -797,22 +803,27 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
+ 	ret = call_qop(q, queue_setup, q, &num_buffers, &num_planes,
+ 		       plane_sizes, q->alloc_devs);
+ 	if (ret)
+-		return ret;
++		goto error;
+ 
+ 	/* Check that driver has set sane values */
+-	if (WARN_ON(!num_planes))
+-		return -EINVAL;
++	if (WARN_ON(!num_planes)) {
++		ret = -EINVAL;
++		goto error;
++	}
+ 
+ 	for (i = 0; i < num_planes; i++)
+-		if (WARN_ON(!plane_sizes[i]))
+-			return -EINVAL;
++		if (WARN_ON(!plane_sizes[i])) {
++			ret = -EINVAL;
++			goto error;
++		}
+ 
+ 	/* Finally, allocate buffers and video memory */
+ 	allocated_buffers =
+ 		__vb2_queue_alloc(q, memory, num_buffers, num_planes, plane_sizes);
+ 	if (allocated_buffers == 0) {
+ 		dprintk(q, 1, "memory allocation failed\n");
+-		return -ENOMEM;
++		ret = -ENOMEM;
++		goto error;
+ 	}
+ 
+ 	/*
+@@ -853,7 +864,8 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
+ 	if (ret < 0) {
+ 		/*
+ 		 * Note: __vb2_queue_free() will subtract 'allocated_buffers'
+-		 * from q->num_buffers.
++		 * from q->num_buffers and it will reset q->memory to
++		 * VB2_MEMORY_UNKNOWN.
+ 		 */
+ 		__vb2_queue_free(q, allocated_buffers);
+ 		mutex_unlock(&q->mmap_lock);
+@@ -869,6 +881,12 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
+ 	q->waiting_for_buffers = !q->is_output;
+ 
+ 	return 0;
++
++error:
++	mutex_lock(&q->mmap_lock);
++	q->memory = VB2_MEMORY_UNKNOWN;
++	mutex_unlock(&q->mmap_lock);
++	return ret;
+ }
+ EXPORT_SYMBOL_GPL(vb2_core_reqbufs);
+ 
+@@ -879,6 +897,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
+ {
+ 	unsigned int num_planes = 0, num_buffers, allocated_buffers;
+ 	unsigned plane_sizes[VB2_MAX_PLANES] = { };
++	bool no_previous_buffers = !q->num_buffers;
+ 	int ret;
+ 
+ 	if (q->num_buffers == VB2_MAX_FRAME) {
+@@ -886,13 +905,19 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
+ 		return -ENOBUFS;
+ 	}
+ 
+-	if (!q->num_buffers) {
++	if (no_previous_buffers) {
+ 		if (q->waiting_in_dqbuf && *count) {
+ 			dprintk(q, 1, "another dup()ped fd is waiting for a buffer\n");
+ 			return -EBUSY;
+ 		}
+ 		memset(q->alloc_devs, 0, sizeof(q->alloc_devs));
++		/*
++		 * Set this now to ensure that drivers see the correct q->memory
++		 * value in the queue_setup op.
++		 */
++		mutex_lock(&q->mmap_lock);
+ 		q->memory = memory;
++		mutex_unlock(&q->mmap_lock);
+ 		q->waiting_for_buffers = !q->is_output;
+ 	} else {
+ 		if (q->memory != memory) {
+@@ -915,14 +940,15 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
+ 	ret = call_qop(q, queue_setup, q, &num_buffers,
+ 		       &num_planes, plane_sizes, q->alloc_devs);
+ 	if (ret)
+-		return ret;
++		goto error;
+ 
+ 	/* Finally, allocate buffers and video memory */
+ 	allocated_buffers = __vb2_queue_alloc(q, memory, num_buffers,
+ 				num_planes, plane_sizes);
+ 	if (allocated_buffers == 0) {
+ 		dprintk(q, 1, "memory allocation failed\n");
+-		return -ENOMEM;
++		ret = -ENOMEM;
++		goto error;
+ 	}
+ 
+ 	/*
+@@ -953,7 +979,8 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
+ 	if (ret < 0) {
+ 		/*
+ 		 * Note: __vb2_queue_free() will subtract 'allocated_buffers'
+-		 * from q->num_buffers.
++		 * from q->num_buffers and it will reset q->memory to
++		 * VB2_MEMORY_UNKNOWN.
+ 		 */
+ 		__vb2_queue_free(q, allocated_buffers);
+ 		mutex_unlock(&q->mmap_lock);
+@@ -968,6 +995,14 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
+ 	*count = allocated_buffers;
+ 
+ 	return 0;
++
++error:
++	if (no_previous_buffers) {
++		mutex_lock(&q->mmap_lock);
++		q->memory = VB2_MEMORY_UNKNOWN;
++		mutex_unlock(&q->mmap_lock);
++	}
++	return ret;
+ }
+ EXPORT_SYMBOL_GPL(vb2_core_create_bufs);
+ 
+@@ -2124,6 +2159,22 @@ static int __find_plane_by_offset(struct vb2_queue *q, unsigned long off,
+ 	struct vb2_buffer *vb;
+ 	unsigned int buffer, plane;
+ 
++	/*
++	 * Sanity checks to ensure the lock is held, MEMORY_MMAP is
++	 * used and fileio isn't active.
++	 */
++	lockdep_assert_held(&q->mmap_lock);
++
++	if (q->memory != VB2_MEMORY_MMAP) {
++		dprintk(q, 1, "queue is not currently set up for mmap\n");
++		return -EINVAL;
++	}
++
++	if (vb2_fileio_is_active(q)) {
++		dprintk(q, 1, "file io in progress\n");
++		return -EBUSY;
++	}
++
+ 	/*
+ 	 * Go over all buffers and their planes, comparing the given offset
+ 	 * with an offset assigned to each plane. If a match is found,
+@@ -2225,11 +2276,6 @@ int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
+ 	int ret;
+ 	unsigned long length;
+ 
+-	if (q->memory != VB2_MEMORY_MMAP) {
+-		dprintk(q, 1, "queue is not currently set up for mmap\n");
+-		return -EINVAL;
+-	}
+-
+ 	/*
+ 	 * Check memory area access mode.
+ 	 */
+@@ -2251,14 +2297,9 @@ int vb2_mmap(struct vb2_queue *q, struct vm_area_struct *vma)
+ 
+ 	mutex_lock(&q->mmap_lock);
+ 
+-	if (vb2_fileio_is_active(q)) {
+-		dprintk(q, 1, "mmap: file io in progress\n");
+-		ret = -EBUSY;
+-		goto unlock;
+-	}
+-
+ 	/*
+-	 * Find the plane corresponding to the offset passed by userspace.
++	 * Find the plane corresponding to the offset passed by userspace. This
++	 * will return an error if not MEMORY_MMAP or file I/O is in progress.
+ 	 */
+ 	ret = __find_plane_by_offset(q, off, &buffer, &plane);
+ 	if (ret)
+@@ -2311,22 +2352,25 @@ unsigned long vb2_get_unmapped_area(struct vb2_queue *q,
+ 	void *vaddr;
+ 	int ret;
+ 
+-	if (q->memory != VB2_MEMORY_MMAP) {
+-		dprintk(q, 1, "queue is not currently set up for mmap\n");
+-		return -EINVAL;
+-	}
++	mutex_lock(&q->mmap_lock);
+ 
+ 	/*
+-	 * Find the plane corresponding to the offset passed by userspace.
++	 * Find the plane corresponding to the offset passed by userspace. This
++	 * will return an error if not MEMORY_MMAP or file I/O is in progress.
+ 	 */
+ 	ret = __find_plane_by_offset(q, off, &buffer, &plane);
+ 	if (ret)
+-		return ret;
++		goto unlock;
+ 
+ 	vb = q->bufs[buffer];
+ 
+ 	vaddr = vb2_plane_vaddr(vb, plane);
++	mutex_unlock(&q->mmap_lock);
+ 	return vaddr ? (unsigned long)vaddr : -EINVAL;
++
++unlock:
++	mutex_unlock(&q->mmap_lock);
++	return ret;
+ }
+ EXPORT_SYMBOL_GPL(vb2_get_unmapped_area);
+ #endif
+diff --git a/drivers/media/v4l2-core/v4l2-dv-timings.c b/drivers/media/v4l2-core/v4l2-dv-timings.c
+index 003c32fed3f75..942d0005c55e8 100644
+--- a/drivers/media/v4l2-core/v4l2-dv-timings.c
++++ b/drivers/media/v4l2-core/v4l2-dv-timings.c
+@@ -145,6 +145,8 @@ bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t,
+ 	const struct v4l2_bt_timings *bt = &t->bt;
+ 	const struct v4l2_bt_timings_cap *cap = &dvcap->bt;
+ 	u32 caps = cap->capabilities;
++	const u32 max_vert = 10240;
++	u32 max_hor = 3 * bt->width;
+ 
+ 	if (t->type != V4L2_DV_BT_656_1120)
+ 		return false;
+@@ -166,14 +168,20 @@ bool v4l2_valid_dv_timings(const struct v4l2_dv_timings *t,
+ 	if (!bt->interlaced &&
+ 	    (bt->il_vbackporch || bt->il_vsync || bt->il_vfrontporch))
+ 		return false;
+-	if (bt->hfrontporch > 2 * bt->width ||
+-	    bt->hsync > 1024 || bt->hbackporch > 1024)
++	/*
++	 * Some video receivers cannot properly separate the frontporch,
++	 * backporch and sync values, and instead they only have the total
++	 * blanking. That can be assigned to any of these three fields.
++	 * So just check that none of these are way out of range.
++	 */
++	if (bt->hfrontporch > max_hor ||
++	    bt->hsync > max_hor || bt->hbackporch > max_hor)
+ 		return false;
+-	if (bt->vfrontporch > 4096 ||
+-	    bt->vsync > 128 || bt->vbackporch > 4096)
++	if (bt->vfrontporch > max_vert ||
++	    bt->vsync > max_vert || bt->vbackporch > max_vert)
+ 		return false;
+-	if (bt->interlaced && (bt->il_vfrontporch > 4096 ||
+-	    bt->il_vsync > 128 || bt->il_vbackporch > 4096))
++	if (bt->interlaced && (bt->il_vfrontporch > max_vert ||
++	    bt->il_vsync > max_vert || bt->il_vbackporch > max_vert))
+ 		return false;
+ 	return fnc == NULL || fnc(t, fnc_handle);
+ }
+diff --git a/drivers/mmc/host/mtk-sd.c b/drivers/mmc/host/mtk-sd.c
+index 99d8881a7d6c2..9871c19d2b4e4 100644
+--- a/drivers/mmc/host/mtk-sd.c
++++ b/drivers/mmc/host/mtk-sd.c
+@@ -2455,13 +2455,11 @@ static int msdc_of_clock_parse(struct platform_device *pdev,
+ 	if (IS_ERR(host->src_clk_cg))
+ 		host->src_clk_cg = NULL;
+ 
+-	host->sys_clk_cg = devm_clk_get_optional(&pdev->dev, "sys_cg");
++	/* If present, always enable for this clock gate */
++	host->sys_clk_cg = devm_clk_get_optional_enabled(&pdev->dev, "sys_cg");
+ 	if (IS_ERR(host->sys_clk_cg))
+ 		host->sys_clk_cg = NULL;
+ 
+-	/* If present, always enable for this clock gate */
+-	clk_prepare_enable(host->sys_clk_cg);
+-
+ 	host->bulk_clks[0].id = "pclk_cg";
+ 	host->bulk_clks[1].id = "axi_cg";
+ 	host->bulk_clks[2].id = "ahb_cg";
+diff --git a/drivers/net/can/usb/esd_usb2.c b/drivers/net/can/usb/esd_usb2.c
+index c6068a251fbed..9ed048cb07e6d 100644
+--- a/drivers/net/can/usb/esd_usb2.c
++++ b/drivers/net/can/usb/esd_usb2.c
+@@ -227,6 +227,10 @@ static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
+ 		u8 rxerr = msg->msg.rx.data[2];
+ 		u8 txerr = msg->msg.rx.data[3];
+ 
++		netdev_dbg(priv->netdev,
++			   "CAN_ERR_EV_EXT: dlc=%#02x state=%02x ecc=%02x rec=%02x tec=%02x\n",
++			   msg->msg.rx.dlc, state, ecc, rxerr, txerr);
++
+ 		skb = alloc_can_err_skb(priv->netdev, &cf);
+ 		if (skb == NULL) {
+ 			stats->rx_dropped++;
+@@ -253,6 +257,8 @@ static void esd_usb2_rx_event(struct esd_usb2_net_priv *priv,
+ 				break;
+ 			default:
+ 				priv->can.state = CAN_STATE_ERROR_ACTIVE;
++				txerr = 0;
++				rxerr = 0;
+ 				break;
+ 			}
+ 		} else {
+diff --git a/drivers/net/dsa/sja1105/sja1105_devlink.c b/drivers/net/dsa/sja1105/sja1105_devlink.c
+index 10c6fea1227fa..bdbbff2a79095 100644
+--- a/drivers/net/dsa/sja1105/sja1105_devlink.c
++++ b/drivers/net/dsa/sja1105/sja1105_devlink.c
+@@ -95,6 +95,8 @@ static int sja1105_setup_devlink_regions(struct dsa_switch *ds)
+ 		if (IS_ERR(region)) {
+ 			while (--i >= 0)
+ 				dsa_devlink_region_destroy(priv->regions[i]);
++
++			kfree(priv->regions);
+ 			return PTR_ERR(region);
+ 		}
+ 
+diff --git a/drivers/net/dsa/sja1105/sja1105_main.c b/drivers/net/dsa/sja1105/sja1105_main.c
+index 1a2a7536ff8aa..ef4d8d6c2bd7a 100644
+--- a/drivers/net/dsa/sja1105/sja1105_main.c
++++ b/drivers/net/dsa/sja1105/sja1105_main.c
+@@ -1025,7 +1025,7 @@ static int sja1105_init_l2_policing(struct sja1105_private *priv)
+ 
+ 		policing[bcast].sharindx = port;
+ 		/* Only SJA1110 has multicast policers */
+-		if (mcast <= table->ops->max_entry_count)
++		if (mcast < table->ops->max_entry_count)
+ 			policing[mcast].sharindx = port;
+ 	}
+ 
+diff --git a/drivers/net/ethernet/aeroflex/greth.c b/drivers/net/ethernet/aeroflex/greth.c
+index c560ad06f0be3..a95bac4e14f6a 100644
+--- a/drivers/net/ethernet/aeroflex/greth.c
++++ b/drivers/net/ethernet/aeroflex/greth.c
+@@ -258,6 +258,7 @@ static int greth_init_rings(struct greth_private *greth)
+ 			if (dma_mapping_error(greth->dev, dma_addr)) {
+ 				if (netif_msg_ifup(greth))
+ 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
++				dev_kfree_skb(skb);
+ 				goto cleanup;
+ 			}
+ 			greth->rx_skbuff[i] = skb;
+diff --git a/drivers/net/ethernet/broadcom/Kconfig b/drivers/net/ethernet/broadcom/Kconfig
+index 1cd3c289f49be..cd1706909044d 100644
+--- a/drivers/net/ethernet/broadcom/Kconfig
++++ b/drivers/net/ethernet/broadcom/Kconfig
+@@ -71,13 +71,14 @@ config BCM63XX_ENET
+ config BCMGENET
+ 	tristate "Broadcom GENET internal MAC support"
+ 	depends on HAS_IOMEM
++	depends on PTP_1588_CLOCK_OPTIONAL || !ARCH_BCM2835
+ 	select MII
+ 	select PHYLIB
+ 	select FIXED_PHY
+ 	select BCM7XXX_PHY
+ 	select MDIO_BCM_UNIMAC
+ 	select DIMLIB
+-	select BROADCOM_PHY if (ARCH_BCM2835 && PTP_1588_CLOCK_OPTIONAL)
++	select BROADCOM_PHY if ARCH_BCM2835
+ 	help
+ 	  This driver supports the built-in Ethernet MACs found in the
+ 	  Broadcom BCM7xxx Set Top Box family chipset.
+diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_main.c b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
+index a27227aeae880..b43b97e15a6f0 100644
+--- a/drivers/net/ethernet/cavium/thunder/nicvf_main.c
++++ b/drivers/net/ethernet/cavium/thunder/nicvf_main.c
+@@ -2250,7 +2250,7 @@ static int nicvf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+ 	err = register_netdev(netdev);
+ 	if (err) {
+ 		dev_err(dev, "Failed to register netdevice\n");
+-		goto err_unregister_interrupts;
++		goto err_destroy_workqueue;
+ 	}
+ 
+ 	nic->msg_enable = debug;
+@@ -2259,6 +2259,8 @@ static int nicvf_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+ 
+ 	return 0;
+ 
++err_destroy_workqueue:
++	destroy_workqueue(nic->nicvf_rx_mode_wq);
+ err_unregister_interrupts:
+ 	nicvf_unregister_interrupts(nic);
+ err_free_netdev:
+diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-flower.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-flower.c
+index cacd454ac696c..c39b866e2582d 100644
+--- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-flower.c
++++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-flower.c
+@@ -132,6 +132,7 @@ int dpaa2_switch_acl_entry_add(struct dpaa2_switch_filter_block *filter_block,
+ 						 DMA_TO_DEVICE);
+ 	if (unlikely(dma_mapping_error(dev, acl_entry_cfg->key_iova))) {
+ 		dev_err(dev, "DMA mapping failed\n");
++		kfree(cmd_buff);
+ 		return -EFAULT;
+ 	}
+ 
+@@ -142,6 +143,7 @@ int dpaa2_switch_acl_entry_add(struct dpaa2_switch_filter_block *filter_block,
+ 			 DMA_TO_DEVICE);
+ 	if (err) {
+ 		dev_err(dev, "dpsw_acl_add_entry() failed %d\n", err);
++		kfree(cmd_buff);
+ 		return err;
+ 	}
+ 
+@@ -172,6 +174,7 @@ dpaa2_switch_acl_entry_remove(struct dpaa2_switch_filter_block *block,
+ 						 DMA_TO_DEVICE);
+ 	if (unlikely(dma_mapping_error(dev, acl_entry_cfg->key_iova))) {
+ 		dev_err(dev, "DMA mapping failed\n");
++		kfree(cmd_buff);
+ 		return -EFAULT;
+ 	}
+ 
+@@ -182,6 +185,7 @@ dpaa2_switch_acl_entry_remove(struct dpaa2_switch_filter_block *block,
+ 			 DMA_TO_DEVICE);
+ 	if (err) {
+ 		dev_err(dev, "dpsw_acl_remove_entry() failed %d\n", err);
++		kfree(cmd_buff);
+ 		return err;
+ 	}
+ 
+diff --git a/drivers/net/ethernet/hisilicon/hisi_femac.c b/drivers/net/ethernet/hisilicon/hisi_femac.c
+index 22bf914f2dbd0..ea3e67cf5ffa1 100644
+--- a/drivers/net/ethernet/hisilicon/hisi_femac.c
++++ b/drivers/net/ethernet/hisilicon/hisi_femac.c
+@@ -283,7 +283,7 @@ static int hisi_femac_rx(struct net_device *dev, int limit)
+ 		skb->protocol = eth_type_trans(skb, dev);
+ 		napi_gro_receive(&priv->napi, skb);
+ 		dev->stats.rx_packets++;
+-		dev->stats.rx_bytes += skb->len;
++		dev->stats.rx_bytes += len;
+ next:
+ 		pos = (pos + 1) % rxq->num;
+ 		if (rx_pkts_num >= limit)
+diff --git a/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c b/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
+index c1aae0fca5e98..0a70fb979f0c3 100644
+--- a/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
++++ b/drivers/net/ethernet/hisilicon/hix5hd2_gmac.c
+@@ -550,7 +550,7 @@ static int hix5hd2_rx(struct net_device *dev, int limit)
+ 		skb->protocol = eth_type_trans(skb, dev);
+ 		napi_gro_receive(&priv->napi, skb);
+ 		dev->stats.rx_packets++;
+-		dev->stats.rx_bytes += skb->len;
++		dev->stats.rx_bytes += len;
+ next:
+ 		pos = dma_ring_incr(pos, RX_DESC_NUM);
+ 	}
+diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c b/drivers/net/ethernet/intel/e1000e/netdev.c
+index 407bbb4cc236f..7e41ce188cc6a 100644
+--- a/drivers/net/ethernet/intel/e1000e/netdev.c
++++ b/drivers/net/ethernet/intel/e1000e/netdev.c
+@@ -5941,9 +5941,9 @@ static netdev_tx_t e1000_xmit_frame(struct sk_buff *skb,
+ 		e1000_tx_queue(tx_ring, tx_flags, count);
+ 		/* Make sure there is space in the ring for the next send. */
+ 		e1000_maybe_stop_tx(tx_ring,
+-				    (MAX_SKB_FRAGS *
++				    ((MAX_SKB_FRAGS + 1) *
+ 				     DIV_ROUND_UP(PAGE_SIZE,
+-						  adapter->tx_fifo_limit) + 2));
++						  adapter->tx_fifo_limit) + 4));
+ 
+ 		if (!netdev_xmit_more() ||
+ 		    netif_xmit_stopped(netdev_get_tx_queue(netdev, 0))) {
+diff --git a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+index 4e32432878053..813889604ff86 100644
+--- a/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
++++ b/drivers/net/ethernet/intel/i40e/i40e_ethtool.c
+@@ -4364,11 +4364,7 @@ static int i40e_check_fdir_input_set(struct i40e_vsi *vsi,
+ 			return -EOPNOTSUPP;
+ 
+ 		/* First 4 bytes of L4 header */
+-		if (usr_ip4_spec->l4_4_bytes == htonl(0xFFFFFFFF))
+-			new_mask |= I40E_L4_SRC_MASK | I40E_L4_DST_MASK;
+-		else if (!usr_ip4_spec->l4_4_bytes)
+-			new_mask &= ~(I40E_L4_SRC_MASK | I40E_L4_DST_MASK);
+-		else
++		if (usr_ip4_spec->l4_4_bytes)
+ 			return -EOPNOTSUPP;
+ 
+ 		/* Filtering on Type of Service is not supported. */
+@@ -4407,11 +4403,7 @@ static int i40e_check_fdir_input_set(struct i40e_vsi *vsi,
+ 		else
+ 			return -EOPNOTSUPP;
+ 
+-		if (usr_ip6_spec->l4_4_bytes == htonl(0xFFFFFFFF))
+-			new_mask |= I40E_L4_SRC_MASK | I40E_L4_DST_MASK;
+-		else if (!usr_ip6_spec->l4_4_bytes)
+-			new_mask &= ~(I40E_L4_SRC_MASK | I40E_L4_DST_MASK);
+-		else
++		if (usr_ip6_spec->l4_4_bytes)
+ 			return -EOPNOTSUPP;
+ 
+ 		/* Filtering on Traffic class is not supported. */
+diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
+index 19b5c56775843..ed2c961902b6c 100644
+--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
++++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
+@@ -10519,6 +10519,21 @@ static int i40e_rebuild_channels(struct i40e_vsi *vsi)
+ 	return 0;
+ }
+ 
++/**
++ * i40e_clean_xps_state - clean xps state for every tx_ring
++ * @vsi: ptr to the VSI
++ **/
++static void i40e_clean_xps_state(struct i40e_vsi *vsi)
++{
++	int i;
++
++	if (vsi->tx_rings)
++		for (i = 0; i < vsi->num_queue_pairs; i++)
++			if (vsi->tx_rings[i])
++				clear_bit(__I40E_TX_XPS_INIT_DONE,
++					  vsi->tx_rings[i]->state);
++}
++
+ /**
+  * i40e_prep_for_reset - prep for the core to reset
+  * @pf: board private structure
+@@ -10543,8 +10558,10 @@ static void i40e_prep_for_reset(struct i40e_pf *pf)
+ 	i40e_pf_quiesce_all_vsi(pf);
+ 
+ 	for (v = 0; v < pf->num_alloc_vsi; v++) {
+-		if (pf->vsi[v])
++		if (pf->vsi[v]) {
++			i40e_clean_xps_state(pf->vsi[v]);
+ 			pf->vsi[v]->seid = 0;
++		}
+ 	}
+ 
+ 	i40e_shutdown_adminq(&pf->hw);
+diff --git a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+index 8f350792e8230..7aedf20a10214 100644
+--- a/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
++++ b/drivers/net/ethernet/intel/i40e/i40e_virtchnl_pf.c
+@@ -1578,6 +1578,7 @@ bool i40e_reset_vf(struct i40e_vf *vf, bool flr)
+ 	i40e_cleanup_reset_vf(vf);
+ 
+ 	i40e_flush(hw);
++	usleep_range(20000, 40000);
+ 	clear_bit(I40E_VF_STATE_RESETTING, &vf->vf_states);
+ 
+ 	return true;
+@@ -1701,6 +1702,7 @@ bool i40e_reset_all_vfs(struct i40e_pf *pf, bool flr)
+ 	}
+ 
+ 	i40e_flush(hw);
++	usleep_range(20000, 40000);
+ 	clear_bit(__I40E_VF_DISABLE, pf->state);
+ 
+ 	return true;
+diff --git a/drivers/net/ethernet/intel/igb/igb_ethtool.c b/drivers/net/ethernet/intel/igb/igb_ethtool.c
+index 3cbb5a89b336f..e99e6e44b525a 100644
+--- a/drivers/net/ethernet/intel/igb/igb_ethtool.c
++++ b/drivers/net/ethernet/intel/igb/igb_ethtool.c
+@@ -1409,6 +1409,8 @@ static int igb_intr_test(struct igb_adapter *adapter, u64 *data)
+ 			*data = 1;
+ 			return -1;
+ 		}
++		wr32(E1000_IVAR_MISC, E1000_IVAR_VALID << 8);
++		wr32(E1000_EIMS, BIT(0));
+ 	} else if (adapter->flags & IGB_FLAG_HAS_MSI) {
+ 		shared_int = false;
+ 		if (request_irq(irq,
+diff --git a/drivers/net/ethernet/marvell/mvneta.c b/drivers/net/ethernet/marvell/mvneta.c
+index 9d460a2706012..5c431a3697622 100644
+--- a/drivers/net/ethernet/marvell/mvneta.c
++++ b/drivers/net/ethernet/marvell/mvneta.c
+@@ -4162,7 +4162,7 @@ static void mvneta_percpu_elect(struct mvneta_port *pp)
+ 	/* Use the cpu associated to the rxq when it is online, in all
+ 	 * the other cases, use the cpu 0 which can't be offline.
+ 	 */
+-	if (cpu_online(pp->rxq_def))
++	if (pp->rxq_def < nr_cpu_ids && cpu_online(pp->rxq_def))
+ 		elected_cpu = pp->rxq_def;
+ 
+ 	max_cpu = num_present_cpus();
+diff --git a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c
+index 75388a65f349e..a42373e6f2593 100644
+--- a/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c
++++ b/drivers/net/ethernet/marvell/octeontx2/nic/otx2_tc.c
+@@ -1090,7 +1090,12 @@ int otx2_init_tc(struct otx2_nic *nic)
+ 		return err;
+ 
+ 	tc->flow_ht_params = tc_flow_ht_params;
+-	return rhashtable_init(&tc->flow_table, &tc->flow_ht_params);
++	err = rhashtable_init(&tc->flow_table, &tc->flow_ht_params);
++	if (err) {
++		kfree(tc->tc_entries_bitmap);
++		tc->tc_entries_bitmap = NULL;
++	}
++	return err;
+ }
+ 
+ void otx2_shutdown_tc(struct otx2_nic *nic)
+diff --git a/drivers/net/ethernet/microchip/encx24j600-regmap.c b/drivers/net/ethernet/microchip/encx24j600-regmap.c
+index 81a8ccca7e5e0..5693784eec5bc 100644
+--- a/drivers/net/ethernet/microchip/encx24j600-regmap.c
++++ b/drivers/net/ethernet/microchip/encx24j600-regmap.c
+@@ -359,7 +359,7 @@ static int regmap_encx24j600_phy_reg_read(void *context, unsigned int reg,
+ 		goto err_out;
+ 
+ 	usleep_range(26, 100);
+-	while ((ret = regmap_read(ctx->regmap, MISTAT, &mistat) != 0) &&
++	while (((ret = regmap_read(ctx->regmap, MISTAT, &mistat)) == 0) &&
+ 	       (mistat & BUSY))
+ 		cpu_relax();
+ 
+@@ -397,7 +397,7 @@ static int regmap_encx24j600_phy_reg_write(void *context, unsigned int reg,
+ 		goto err_out;
+ 
+ 	usleep_range(26, 100);
+-	while ((ret = regmap_read(ctx->regmap, MISTAT, &mistat) != 0) &&
++	while (((ret = regmap_read(ctx->regmap, MISTAT, &mistat)) == 0) &&
+ 	       (mistat & BUSY))
+ 		cpu_relax();
+ 
+diff --git a/drivers/net/ethernet/microchip/sparx5/sparx5_main.c b/drivers/net/ethernet/microchip/sparx5/sparx5_main.c
+index 435ac224e38ed..0463f20da17b3 100644
+--- a/drivers/net/ethernet/microchip/sparx5/sparx5_main.c
++++ b/drivers/net/ethernet/microchip/sparx5/sparx5_main.c
+@@ -829,6 +829,8 @@ static int mchp_sparx5_probe(struct platform_device *pdev)
+ 
+ cleanup_ports:
+ 	sparx5_cleanup_ports(sparx5);
++	if (sparx5->mact_queue)
++		destroy_workqueue(sparx5->mact_queue);
+ cleanup_config:
+ 	kfree(configs);
+ cleanup_pnode:
+@@ -852,6 +854,7 @@ static int mchp_sparx5_remove(struct platform_device *pdev)
+ 	sparx5_cleanup_ports(sparx5);
+ 	/* Unregister netdevs */
+ 	sparx5_unregister_notifier_blocks(sparx5);
++	destroy_workqueue(sparx5->mact_queue);
+ 
+ 	return 0;
+ }
+diff --git a/drivers/net/ethernet/microsoft/mana/gdma.h b/drivers/net/ethernet/microsoft/mana/gdma.h
+index 41ecd156e95f5..1038bdf28ec08 100644
+--- a/drivers/net/ethernet/microsoft/mana/gdma.h
++++ b/drivers/net/ethernet/microsoft/mana/gdma.h
+@@ -488,7 +488,14 @@ enum {
+ 
+ #define GDMA_DRV_CAP_FLAG_1_EQ_SHARING_MULTI_VPORT BIT(0)
+ 
+-#define GDMA_DRV_CAP_FLAGS1 GDMA_DRV_CAP_FLAG_1_EQ_SHARING_MULTI_VPORT
++/* Advertise to the NIC firmware: the NAPI work_done variable race is fixed,
++ * so the driver is able to reliably support features like busy_poll.
++ */
++#define GDMA_DRV_CAP_FLAG_1_NAPI_WKDONE_FIX BIT(2)
++
++#define GDMA_DRV_CAP_FLAGS1 \
++	(GDMA_DRV_CAP_FLAG_1_EQ_SHARING_MULTI_VPORT | \
++	 GDMA_DRV_CAP_FLAG_1_NAPI_WKDONE_FIX)
+ 
+ #define GDMA_DRV_CAP_FLAGS2 0
+ 
+diff --git a/drivers/net/ethernet/microsoft/mana/mana_en.c b/drivers/net/ethernet/microsoft/mana/mana_en.c
+index 18dc64d7f412f..4b8c239932178 100644
+--- a/drivers/net/ethernet/microsoft/mana/mana_en.c
++++ b/drivers/net/ethernet/microsoft/mana/mana_en.c
+@@ -1071,10 +1071,11 @@ static void mana_poll_rx_cq(struct mana_cq *cq)
+ 	}
+ }
+ 
+-static void mana_cq_handler(void *context, struct gdma_queue *gdma_queue)
++static int mana_cq_handler(void *context, struct gdma_queue *gdma_queue)
+ {
+ 	struct mana_cq *cq = context;
+ 	u8 arm_bit;
++	int w;
+ 
+ 	WARN_ON_ONCE(cq->gdma_cq != gdma_queue);
+ 
+@@ -1083,26 +1084,31 @@ static void mana_cq_handler(void *context, struct gdma_queue *gdma_queue)
+ 	else
+ 		mana_poll_tx_cq(cq);
+ 
+-	if (cq->work_done < cq->budget &&
+-	    napi_complete_done(&cq->napi, cq->work_done)) {
++	w = cq->work_done;
++
++	if (w < cq->budget &&
++	    napi_complete_done(&cq->napi, w)) {
+ 		arm_bit = SET_ARM_BIT;
+ 	} else {
+ 		arm_bit = 0;
+ 	}
+ 
+ 	mana_gd_ring_cq(gdma_queue, arm_bit);
++
++	return w;
+ }
+ 
+ static int mana_poll(struct napi_struct *napi, int budget)
+ {
+ 	struct mana_cq *cq = container_of(napi, struct mana_cq, napi);
++	int w;
+ 
+ 	cq->work_done = 0;
+ 	cq->budget = budget;
+ 
+-	mana_cq_handler(cq, cq->gdma_cq);
++	w = mana_cq_handler(cq, cq->gdma_cq);
+ 
+-	return min(cq->work_done, budget);
++	return min(w, budget);
+ }
+ 
+ static void mana_schedule_napi(void *context, struct gdma_queue *gdma_queue)
+diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+index 9f5cac4000da6..5c234a8158c71 100644
+--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
++++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_platform.c
+@@ -108,10 +108,10 @@ static struct stmmac_axi *stmmac_axi_setup(struct platform_device *pdev)
+ 
+ 	axi->axi_lpi_en = of_property_read_bool(np, "snps,lpi_en");
+ 	axi->axi_xit_frm = of_property_read_bool(np, "snps,xit_frm");
+-	axi->axi_kbbe = of_property_read_bool(np, "snps,axi_kbbe");
+-	axi->axi_fb = of_property_read_bool(np, "snps,axi_fb");
+-	axi->axi_mb = of_property_read_bool(np, "snps,axi_mb");
+-	axi->axi_rb =  of_property_read_bool(np, "snps,axi_rb");
++	axi->axi_kbbe = of_property_read_bool(np, "snps,kbbe");
++	axi->axi_fb = of_property_read_bool(np, "snps,fb");
++	axi->axi_mb = of_property_read_bool(np, "snps,mb");
++	axi->axi_rb =  of_property_read_bool(np, "snps,rb");
+ 
+ 	if (of_property_read_u32(np, "snps,wr_osr_lmt", &axi->axi_wr_osr_lmt))
+ 		axi->axi_wr_osr_lmt = 1;
+diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c
+index 96592a20c61ff..0362917fce7a9 100644
+--- a/drivers/net/ieee802154/ca8210.c
++++ b/drivers/net/ieee802154/ca8210.c
+@@ -927,7 +927,7 @@ static int ca8210_spi_transfer(
+ 
+ 	dev_dbg(&spi->dev, "%s called\n", __func__);
+ 
+-	cas_ctl = kmalloc(sizeof(*cas_ctl), GFP_ATOMIC);
++	cas_ctl = kzalloc(sizeof(*cas_ctl), GFP_ATOMIC);
+ 	if (!cas_ctl)
+ 		return -ENOMEM;
+ 
+diff --git a/drivers/net/ieee802154/cc2520.c b/drivers/net/ieee802154/cc2520.c
+index 4517517215f2b..a8369bfa4050b 100644
+--- a/drivers/net/ieee802154/cc2520.c
++++ b/drivers/net/ieee802154/cc2520.c
+@@ -970,7 +970,7 @@ static int cc2520_hw_init(struct cc2520_private *priv)
+ 
+ 		if (timeout-- <= 0) {
+ 			dev_err(&priv->spi->dev, "oscillator start failed!\n");
+-			return ret;
++			return -ETIMEDOUT;
+ 		}
+ 		udelay(1);
+ 	} while (!(status & CC2520_STATUS_XOSC32M_STABLE));
+diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
+index aa9d0dfeda5ab..88e44eb392851 100644
+--- a/drivers/net/macsec.c
++++ b/drivers/net/macsec.c
+@@ -3675,6 +3675,7 @@ static const struct nla_policy macsec_rtnl_policy[IFLA_MACSEC_MAX + 1] = {
+ 	[IFLA_MACSEC_SCB] = { .type = NLA_U8 },
+ 	[IFLA_MACSEC_REPLAY_PROTECT] = { .type = NLA_U8 },
+ 	[IFLA_MACSEC_VALIDATION] = { .type = NLA_U8 },
++	[IFLA_MACSEC_OFFLOAD] = { .type = NLA_U8 },
+ };
+ 
+ static void macsec_free_netdev(struct net_device *dev)
+diff --git a/drivers/net/mdio/fwnode_mdio.c b/drivers/net/mdio/fwnode_mdio.c
+index 40e745a1d1854..2c47efdae73b4 100644
+--- a/drivers/net/mdio/fwnode_mdio.c
++++ b/drivers/net/mdio/fwnode_mdio.c
+@@ -77,6 +77,7 @@ int fwnode_mdiobus_phy_device_register(struct mii_bus *mdio,
+ 	 */
+ 	rc = phy_device_register(phy);
+ 	if (rc) {
++		device_set_node(&phy->mdio.dev, NULL);
+ 		fwnode_handle_put(child);
+ 		return rc;
+ 	}
+@@ -110,8 +111,8 @@ int fwnode_mdiobus_register_phy(struct mii_bus *bus,
+ 	else
+ 		phy = phy_device_create(bus, addr, phy_id, 0, NULL);
+ 	if (IS_ERR(phy)) {
+-		unregister_mii_timestamper(mii_ts);
+-		return PTR_ERR(phy);
++		rc = PTR_ERR(phy);
++		goto clean_mii_ts;
+ 	}
+ 
+ 	if (is_acpi_node(child)) {
+@@ -125,17 +126,14 @@ int fwnode_mdiobus_register_phy(struct mii_bus *bus,
+ 		/* All data is now stored in the phy struct, so register it */
+ 		rc = phy_device_register(phy);
+ 		if (rc) {
+-			phy_device_free(phy);
+-			fwnode_handle_put(phy->mdio.dev.fwnode);
+-			return rc;
++			phy->mdio.dev.fwnode = NULL;
++			fwnode_handle_put(child);
++			goto clean_phy;
+ 		}
+ 	} else if (is_of_node(child)) {
+ 		rc = fwnode_mdiobus_phy_device_register(bus, phy, child, addr);
+-		if (rc) {
+-			unregister_mii_timestamper(mii_ts);
+-			phy_device_free(phy);
+-			return rc;
+-		}
++		if (rc)
++			goto clean_phy;
+ 	}
+ 
+ 	/* phy->mii_ts may already be defined by the PHY driver. A
+@@ -145,5 +143,12 @@ int fwnode_mdiobus_register_phy(struct mii_bus *bus,
+ 	if (mii_ts)
+ 		phy->mii_ts = mii_ts;
+ 	return 0;
++
++clean_phy:
++	phy_device_free(phy);
++clean_mii_ts:
++	unregister_mii_timestamper(mii_ts);
++
++	return rc;
+ }
+ EXPORT_SYMBOL(fwnode_mdiobus_register_phy);
+diff --git a/drivers/net/mdio/of_mdio.c b/drivers/net/mdio/of_mdio.c
+index 796e9c7857d09..510822d6d0d90 100644
+--- a/drivers/net/mdio/of_mdio.c
++++ b/drivers/net/mdio/of_mdio.c
+@@ -68,8 +68,9 @@ static int of_mdiobus_register_device(struct mii_bus *mdio,
+ 	/* All data is now stored in the mdiodev struct; register it. */
+ 	rc = mdio_device_register(mdiodev);
+ 	if (rc) {
++		device_set_node(&mdiodev->dev, NULL);
++		fwnode_handle_put(fwnode);
+ 		mdio_device_free(mdiodev);
+-		of_node_put(child);
+ 		return rc;
+ 	}
+ 
+diff --git a/drivers/net/phy/mdio_device.c b/drivers/net/phy/mdio_device.c
+index 250742ffdfd91..044828d081d22 100644
+--- a/drivers/net/phy/mdio_device.c
++++ b/drivers/net/phy/mdio_device.c
+@@ -21,6 +21,7 @@
+ #include <linux/slab.h>
+ #include <linux/string.h>
+ #include <linux/unistd.h>
++#include <linux/property.h>
+ 
+ void mdio_device_free(struct mdio_device *mdiodev)
+ {
+@@ -30,6 +31,7 @@ EXPORT_SYMBOL(mdio_device_free);
+ 
+ static void mdio_device_release(struct device *dev)
+ {
++	fwnode_handle_put(dev->fwnode);
+ 	kfree(to_mdio_device(dev));
+ }
+ 
+diff --git a/drivers/net/phy/mxl-gpy.c b/drivers/net/phy/mxl-gpy.c
+index 5ce1bf03bbd71..f9c70476d7e8c 100644
+--- a/drivers/net/phy/mxl-gpy.c
++++ b/drivers/net/phy/mxl-gpy.c
+@@ -96,6 +96,7 @@ static int gpy_config_init(struct phy_device *phydev)
+ 
+ static int gpy_probe(struct phy_device *phydev)
+ {
++	int fw_version;
+ 	int ret;
+ 
+ 	if (!phydev->is_c45) {
+@@ -105,12 +106,12 @@ static int gpy_probe(struct phy_device *phydev)
+ 	}
+ 
+ 	/* Show GPY PHY FW version in dmesg */
+-	ret = phy_read(phydev, PHY_FWV);
+-	if (ret < 0)
+-		return ret;
++	fw_version = phy_read(phydev, PHY_FWV);
++	if (fw_version < 0)
++		return fw_version;
+ 
+-	phydev_info(phydev, "Firmware Version: 0x%04X (%s)\n", ret,
+-		    (ret & PHY_FWV_REL_MASK) ? "release" : "test");
++	phydev_info(phydev, "Firmware Version: 0x%04X (%s)\n", fw_version,
++		    (fw_version & PHY_FWV_REL_MASK) ? "release" : "test");
+ 
+ 	return 0;
+ }
+diff --git a/drivers/net/plip/plip.c b/drivers/net/plip/plip.c
+index 2a2cb9d453e8e..b1776116f9f7d 100644
+--- a/drivers/net/plip/plip.c
++++ b/drivers/net/plip/plip.c
+@@ -446,12 +446,12 @@ plip_bh_timeout_error(struct net_device *dev, struct net_local *nl,
+ 	}
+ 	rcv->state = PLIP_PK_DONE;
+ 	if (rcv->skb) {
+-		kfree_skb(rcv->skb);
++		dev_kfree_skb_irq(rcv->skb);
+ 		rcv->skb = NULL;
+ 	}
+ 	snd->state = PLIP_PK_DONE;
+ 	if (snd->skb) {
+-		dev_kfree_skb(snd->skb);
++		dev_consume_skb_irq(snd->skb);
+ 		snd->skb = NULL;
+ 	}
+ 	spin_unlock_irq(&nl->lock);
+diff --git a/drivers/net/thunderbolt.c b/drivers/net/thunderbolt.c
+index 1291496402253..3395dcb0b262b 100644
+--- a/drivers/net/thunderbolt.c
++++ b/drivers/net/thunderbolt.c
+@@ -902,6 +902,7 @@ static int tbnet_open(struct net_device *dev)
+ 				tbnet_start_poll, net);
+ 	if (!ring) {
+ 		netdev_err(dev, "failed to allocate Rx ring\n");
++		tb_xdomain_release_out_hopid(xd, hopid);
+ 		tb_ring_free(net->tx_ring.ring);
+ 		net->tx_ring.ring = NULL;
+ 		return -ENOMEM;
+diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c
+index d886f903e4285..7b358b896a6d7 100644
+--- a/drivers/net/usb/qmi_wwan.c
++++ b/drivers/net/usb/qmi_wwan.c
+@@ -1413,6 +1413,7 @@ static const struct usb_device_id products[] = {
+ 	{QMI_FIXED_INTF(0x0489, 0xe0b4, 0)},	/* Foxconn T77W968 LTE */
+ 	{QMI_FIXED_INTF(0x0489, 0xe0b5, 0)},	/* Foxconn T77W968 LTE with eSIM support*/
+ 	{QMI_FIXED_INTF(0x2692, 0x9025, 4)},    /* Cellient MPL200 (rebranded Qualcomm 05c6:9025) */
++	{QMI_QUIRK_SET_DTR(0x1546, 0x1342, 4)},	/* u-blox LARA-L6 */
+ 
+ 	/* 4. Gobi 1000 devices */
+ 	{QMI_GOBI1K_DEVICE(0x05c6, 0x9212)},	/* Acer Gobi Modem Device */
+diff --git a/drivers/net/vmxnet3/vmxnet3_drv.c b/drivers/net/vmxnet3/vmxnet3_drv.c
+index bc3192cf48e3e..21896e2213004 100644
+--- a/drivers/net/vmxnet3/vmxnet3_drv.c
++++ b/drivers/net/vmxnet3/vmxnet3_drv.c
+@@ -75,8 +75,14 @@ vmxnet3_enable_all_intrs(struct vmxnet3_adapter *adapter)
+ 
+ 	for (i = 0; i < adapter->intr.num_intrs; i++)
+ 		vmxnet3_enable_intr(adapter, i);
+-	adapter->shared->devRead.intrConf.intrCtrl &=
++	if (!VMXNET3_VERSION_GE_6(adapter) ||
++	    !adapter->queuesExtEnabled) {
++		adapter->shared->devRead.intrConf.intrCtrl &=
++					cpu_to_le32(~VMXNET3_IC_DISABLE_ALL);
++	} else {
++		adapter->shared->devReadExt.intrConfExt.intrCtrl &=
+ 					cpu_to_le32(~VMXNET3_IC_DISABLE_ALL);
++	}
+ }
+ 
+ 
+@@ -85,8 +91,14 @@ vmxnet3_disable_all_intrs(struct vmxnet3_adapter *adapter)
+ {
+ 	int i;
+ 
+-	adapter->shared->devRead.intrConf.intrCtrl |=
++	if (!VMXNET3_VERSION_GE_6(adapter) ||
++	    !adapter->queuesExtEnabled) {
++		adapter->shared->devRead.intrConf.intrCtrl |=
++					cpu_to_le32(VMXNET3_IC_DISABLE_ALL);
++	} else {
++		adapter->shared->devReadExt.intrConfExt.intrCtrl |=
+ 					cpu_to_le32(VMXNET3_IC_DISABLE_ALL);
++	}
+ 	for (i = 0; i < adapter->intr.num_intrs; i++)
+ 		vmxnet3_disable_intr(adapter, i);
+ }
+@@ -1350,6 +1362,7 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
+ 	};
+ 	u32 num_pkts = 0;
+ 	bool skip_page_frags = false;
++	bool encap_lro = false;
+ 	struct Vmxnet3_RxCompDesc *rcd;
+ 	struct vmxnet3_rx_ctx *ctx = &rq->rx_ctx;
+ 	u16 segCnt = 0, mss = 0;
+@@ -1508,13 +1521,18 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
+ 			if (VMXNET3_VERSION_GE_2(adapter) &&
+ 			    rcd->type == VMXNET3_CDTYPE_RXCOMP_LRO) {
+ 				struct Vmxnet3_RxCompDescExt *rcdlro;
++				union Vmxnet3_GenericDesc *gdesc;
++
+ 				rcdlro = (struct Vmxnet3_RxCompDescExt *)rcd;
++				gdesc = (union Vmxnet3_GenericDesc *)rcd;
+ 
+ 				segCnt = rcdlro->segCnt;
+ 				WARN_ON_ONCE(segCnt == 0);
+ 				mss = rcdlro->mss;
+ 				if (unlikely(segCnt <= 1))
+ 					segCnt = 0;
++				encap_lro = (le32_to_cpu(gdesc->dword[0]) &
++					(1UL << VMXNET3_RCD_HDR_INNER_SHIFT));
+ 			} else {
+ 				segCnt = 0;
+ 			}
+@@ -1582,7 +1600,7 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
+ 			vmxnet3_rx_csum(adapter, skb,
+ 					(union Vmxnet3_GenericDesc *)rcd);
+ 			skb->protocol = eth_type_trans(skb, adapter->netdev);
+-			if (!rcd->tcp ||
++			if ((!rcd->tcp && !encap_lro) ||
+ 			    !(adapter->netdev->features & NETIF_F_LRO))
+ 				goto not_lro;
+ 
+@@ -1591,7 +1609,7 @@ vmxnet3_rq_rx_complete(struct vmxnet3_rx_queue *rq,
+ 					SKB_GSO_TCPV4 : SKB_GSO_TCPV6;
+ 				skb_shinfo(skb)->gso_size = mss;
+ 				skb_shinfo(skb)->gso_segs = segCnt;
+-			} else if (segCnt != 0 || skb->len > mtu) {
++			} else if ((segCnt != 0 || skb->len > mtu) && !encap_lro) {
+ 				u32 hlen;
+ 
+ 				hlen = vmxnet3_get_hdr_len(adapter, skb,
+@@ -1620,6 +1638,7 @@ not_lro:
+ 				napi_gro_receive(&rq->napi, skb);
+ 
+ 			ctx->skb = NULL;
++			encap_lro = false;
+ 			num_pkts++;
+ 		}
+ 
+diff --git a/drivers/net/xen-netback/common.h b/drivers/net/xen-netback/common.h
+index d9dea4829c86e..adfd21aa5b6ad 100644
+--- a/drivers/net/xen-netback/common.h
++++ b/drivers/net/xen-netback/common.h
+@@ -48,7 +48,6 @@
+ #include <linux/debugfs.h>
+ 
+ typedef unsigned int pending_ring_idx_t;
+-#define INVALID_PENDING_RING_IDX (~0U)
+ 
+ struct pending_tx_info {
+ 	struct xen_netif_tx_request req; /* tx request */
+@@ -82,8 +81,6 @@ struct xenvif_rx_meta {
+ /* Discriminate from any valid pending_idx value. */
+ #define INVALID_PENDING_IDX 0xFFFF
+ 
+-#define MAX_BUFFER_OFFSET XEN_PAGE_SIZE
+-
+ #define MAX_PENDING_REQS XEN_NETIF_TX_RING_SIZE
+ 
+ /* The maximum number of frags is derived from the size of a grant (same
+@@ -367,11 +364,6 @@ void xenvif_free(struct xenvif *vif);
+ int xenvif_xenbus_init(void);
+ void xenvif_xenbus_fini(void);
+ 
+-int xenvif_schedulable(struct xenvif *vif);
+-
+-int xenvif_queue_stopped(struct xenvif_queue *queue);
+-void xenvif_wake_queue(struct xenvif_queue *queue);
+-
+ /* (Un)Map communication rings. */
+ void xenvif_unmap_frontend_data_rings(struct xenvif_queue *queue);
+ int xenvif_map_frontend_data_rings(struct xenvif_queue *queue,
+@@ -394,8 +386,7 @@ int xenvif_dealloc_kthread(void *data);
+ irqreturn_t xenvif_ctrl_irq_fn(int irq, void *data);
+ 
+ bool xenvif_have_rx_work(struct xenvif_queue *queue, bool test_kthread);
+-void xenvif_rx_action(struct xenvif_queue *queue);
+-void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb);
++bool xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb);
+ 
+ void xenvif_carrier_on(struct xenvif *vif);
+ 
+@@ -403,9 +394,6 @@ void xenvif_carrier_on(struct xenvif *vif);
+ void xenvif_zerocopy_callback(struct sk_buff *skb, struct ubuf_info *ubuf,
+ 			      bool zerocopy_success);
+ 
+-/* Unmap a pending page and release it back to the guest */
+-void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx);
+-
+ static inline pending_ring_idx_t nr_pending_reqs(struct xenvif_queue *queue)
+ {
+ 	return MAX_PENDING_REQS -
+diff --git a/drivers/net/xen-netback/interface.c b/drivers/net/xen-netback/interface.c
+index c58996c1e2309..e1a5610b1747e 100644
+--- a/drivers/net/xen-netback/interface.c
++++ b/drivers/net/xen-netback/interface.c
+@@ -70,7 +70,7 @@ void xenvif_skb_zerocopy_complete(struct xenvif_queue *queue)
+ 	wake_up(&queue->dealloc_wq);
+ }
+ 
+-int xenvif_schedulable(struct xenvif *vif)
++static int xenvif_schedulable(struct xenvif *vif)
+ {
+ 	return netif_running(vif->dev) &&
+ 		test_bit(VIF_STATUS_CONNECTED, &vif->status) &&
+@@ -178,20 +178,6 @@ irqreturn_t xenvif_interrupt(int irq, void *dev_id)
+ 	return IRQ_HANDLED;
+ }
+ 
+-int xenvif_queue_stopped(struct xenvif_queue *queue)
+-{
+-	struct net_device *dev = queue->vif->dev;
+-	unsigned int id = queue->id;
+-	return netif_tx_queue_stopped(netdev_get_tx_queue(dev, id));
+-}
+-
+-void xenvif_wake_queue(struct xenvif_queue *queue)
+-{
+-	struct net_device *dev = queue->vif->dev;
+-	unsigned int id = queue->id;
+-	netif_tx_wake_queue(netdev_get_tx_queue(dev, id));
+-}
+-
+ static u16 xenvif_select_queue(struct net_device *dev, struct sk_buff *skb,
+ 			       struct net_device *sb_dev)
+ {
+@@ -269,14 +255,16 @@ xenvif_start_xmit(struct sk_buff *skb, struct net_device *dev)
+ 	if (vif->hash.alg == XEN_NETIF_CTRL_HASH_ALGORITHM_NONE)
+ 		skb_clear_hash(skb);
+ 
+-	xenvif_rx_queue_tail(queue, skb);
++	if (!xenvif_rx_queue_tail(queue, skb))
++		goto drop;
++
+ 	xenvif_kick_thread(queue);
+ 
+ 	return NETDEV_TX_OK;
+ 
+  drop:
+ 	vif->dev->stats.tx_dropped++;
+-	dev_kfree_skb(skb);
++	dev_kfree_skb_any(skb);
+ 	return NETDEV_TX_OK;
+ }
+ 
+diff --git a/drivers/net/xen-netback/netback.c b/drivers/net/xen-netback/netback.c
+index 32d5bc4919d8c..26428db845bea 100644
+--- a/drivers/net/xen-netback/netback.c
++++ b/drivers/net/xen-netback/netback.c
+@@ -112,6 +112,8 @@ static void make_tx_response(struct xenvif_queue *queue,
+ 			     s8       st);
+ static void push_tx_responses(struct xenvif_queue *queue);
+ 
++static void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx);
++
+ static inline int tx_work_todo(struct xenvif_queue *queue);
+ 
+ static inline unsigned long idx_to_pfn(struct xenvif_queue *queue,
+@@ -330,10 +332,13 @@ static int xenvif_count_requests(struct xenvif_queue *queue,
+ 
+ 
+ struct xenvif_tx_cb {
+-	u16 pending_idx;
++	u16 copy_pending_idx[XEN_NETBK_LEGACY_SLOTS_MAX + 1];
++	u8 copy_count;
+ };
+ 
+ #define XENVIF_TX_CB(skb) ((struct xenvif_tx_cb *)(skb)->cb)
++#define copy_pending_idx(skb, i) (XENVIF_TX_CB(skb)->copy_pending_idx[i])
++#define copy_count(skb) (XENVIF_TX_CB(skb)->copy_count)
+ 
+ static inline void xenvif_tx_create_map_op(struct xenvif_queue *queue,
+ 					   u16 pending_idx,
+@@ -368,31 +373,93 @@ static inline struct sk_buff *xenvif_alloc_skb(unsigned int size)
+ 	return skb;
+ }
+ 
+-static struct gnttab_map_grant_ref *xenvif_get_requests(struct xenvif_queue *queue,
+-							struct sk_buff *skb,
+-							struct xen_netif_tx_request *txp,
+-							struct gnttab_map_grant_ref *gop,
+-							unsigned int frag_overflow,
+-							struct sk_buff *nskb)
++static void xenvif_get_requests(struct xenvif_queue *queue,
++				struct sk_buff *skb,
++				struct xen_netif_tx_request *first,
++				struct xen_netif_tx_request *txfrags,
++			        unsigned *copy_ops,
++			        unsigned *map_ops,
++				unsigned int frag_overflow,
++				struct sk_buff *nskb,
++				unsigned int extra_count,
++				unsigned int data_len)
+ {
+ 	struct skb_shared_info *shinfo = skb_shinfo(skb);
+ 	skb_frag_t *frags = shinfo->frags;
+-	u16 pending_idx = XENVIF_TX_CB(skb)->pending_idx;
+-	int start;
++	u16 pending_idx;
+ 	pending_ring_idx_t index;
+ 	unsigned int nr_slots;
++	struct gnttab_copy *cop = queue->tx_copy_ops + *copy_ops;
++	struct gnttab_map_grant_ref *gop = queue->tx_map_ops + *map_ops;
++	struct xen_netif_tx_request *txp = first;
++
++	nr_slots = shinfo->nr_frags + 1;
++
++	copy_count(skb) = 0;
+ 
+-	nr_slots = shinfo->nr_frags;
++	/* Create copy ops for exactly data_len bytes into the skb head. */
++	__skb_put(skb, data_len);
++	while (data_len > 0) {
++		int amount = data_len > txp->size ? txp->size : data_len;
+ 
+-	/* Skip first skb fragment if it is on same page as header fragment. */
+-	start = (frag_get_pending_idx(&shinfo->frags[0]) == pending_idx);
++		cop->source.u.ref = txp->gref;
++		cop->source.domid = queue->vif->domid;
++		cop->source.offset = txp->offset;
+ 
+-	for (shinfo->nr_frags = start; shinfo->nr_frags < nr_slots;
+-	     shinfo->nr_frags++, txp++, gop++) {
++		cop->dest.domid = DOMID_SELF;
++		cop->dest.offset = (offset_in_page(skb->data +
++						   skb_headlen(skb) -
++						   data_len)) & ~XEN_PAGE_MASK;
++		cop->dest.u.gmfn = virt_to_gfn(skb->data + skb_headlen(skb)
++				               - data_len);
++
++		cop->len = amount;
++		cop->flags = GNTCOPY_source_gref;
++
++		index = pending_index(queue->pending_cons);
++		pending_idx = queue->pending_ring[index];
++		callback_param(queue, pending_idx).ctx = NULL;
++		copy_pending_idx(skb, copy_count(skb)) = pending_idx;
++		copy_count(skb)++;
++
++		cop++;
++		data_len -= amount;
++
++		if (amount == txp->size) {
++			/* The copy op covered the full tx_request */
++
++			memcpy(&queue->pending_tx_info[pending_idx].req,
++			       txp, sizeof(*txp));
++			queue->pending_tx_info[pending_idx].extra_count =
++				(txp == first) ? extra_count : 0;
++
++			if (txp == first)
++				txp = txfrags;
++			else
++				txp++;
++			queue->pending_cons++;
++			nr_slots--;
++		} else {
++			/* The copy op partially covered the tx_request.
++			 * The remainder will be mapped.
++			 */
++			txp->offset += amount;
++			txp->size -= amount;
++		}
++	}
++
++	for (shinfo->nr_frags = 0; shinfo->nr_frags < nr_slots;
++	     shinfo->nr_frags++, gop++) {
+ 		index = pending_index(queue->pending_cons++);
+ 		pending_idx = queue->pending_ring[index];
+-		xenvif_tx_create_map_op(queue, pending_idx, txp, 0, gop);
++		xenvif_tx_create_map_op(queue, pending_idx, txp,
++				        txp == first ? extra_count : 0, gop);
+ 		frag_set_pending_idx(&frags[shinfo->nr_frags], pending_idx);
++
++		if (txp == first)
++			txp = txfrags;
++		else
++			txp++;
+ 	}
+ 
+ 	if (frag_overflow) {
+@@ -413,7 +480,8 @@ static struct gnttab_map_grant_ref *xenvif_get_requests(struct xenvif_queue *que
+ 		skb_shinfo(skb)->frag_list = nskb;
+ 	}
+ 
+-	return gop;
++	(*copy_ops) = cop - queue->tx_copy_ops;
++	(*map_ops) = gop - queue->tx_map_ops;
+ }
+ 
+ static inline void xenvif_grant_handle_set(struct xenvif_queue *queue,
+@@ -449,7 +517,7 @@ static int xenvif_tx_check_gop(struct xenvif_queue *queue,
+ 			       struct gnttab_copy **gopp_copy)
+ {
+ 	struct gnttab_map_grant_ref *gop_map = *gopp_map;
+-	u16 pending_idx = XENVIF_TX_CB(skb)->pending_idx;
++	u16 pending_idx;
+ 	/* This always points to the shinfo of the skb being checked, which
+ 	 * could be either the first or the one on the frag_list
+ 	 */
+@@ -460,24 +528,37 @@ static int xenvif_tx_check_gop(struct xenvif_queue *queue,
+ 	struct skb_shared_info *first_shinfo = NULL;
+ 	int nr_frags = shinfo->nr_frags;
+ 	const bool sharedslot = nr_frags &&
+-				frag_get_pending_idx(&shinfo->frags[0]) == pending_idx;
+-	int i, err;
++				frag_get_pending_idx(&shinfo->frags[0]) ==
++				    copy_pending_idx(skb, copy_count(skb) - 1);
++	int i, err = 0;
+ 
+-	/* Check status of header. */
+-	err = (*gopp_copy)->status;
+-	if (unlikely(err)) {
+-		if (net_ratelimit())
+-			netdev_dbg(queue->vif->dev,
+-				   "Grant copy of header failed! status: %d pending_idx: %u ref: %u\n",
+-				   (*gopp_copy)->status,
+-				   pending_idx,
+-				   (*gopp_copy)->source.u.ref);
+-		/* The first frag might still have this slot mapped */
+-		if (!sharedslot)
+-			xenvif_idx_release(queue, pending_idx,
+-					   XEN_NETIF_RSP_ERROR);
++	for (i = 0; i < copy_count(skb); i++) {
++		int newerr;
++
++		/* Check status of header. */
++		pending_idx = copy_pending_idx(skb, i);
++
++		newerr = (*gopp_copy)->status;
++		if (likely(!newerr)) {
++			/* The first frag might still have this slot mapped */
++			if (i < copy_count(skb) - 1 || !sharedslot)
++				xenvif_idx_release(queue, pending_idx,
++						   XEN_NETIF_RSP_OKAY);
++		} else {
++			err = newerr;
++			if (net_ratelimit())
++				netdev_dbg(queue->vif->dev,
++					   "Grant copy of header failed! status: %d pending_idx: %u ref: %u\n",
++					   (*gopp_copy)->status,
++					   pending_idx,
++					   (*gopp_copy)->source.u.ref);
++			/* The first frag might still have this slot mapped */
++			if (i < copy_count(skb) - 1 || !sharedslot)
++				xenvif_idx_release(queue, pending_idx,
++						   XEN_NETIF_RSP_ERROR);
++		}
++		(*gopp_copy)++;
+ 	}
+-	(*gopp_copy)++;
+ 
+ check_frags:
+ 	for (i = 0; i < nr_frags; i++, gop_map++) {
+@@ -524,14 +605,6 @@ check_frags:
+ 		if (err)
+ 			continue;
+ 
+-		/* First error: if the header haven't shared a slot with the
+-		 * first frag, release it as well.
+-		 */
+-		if (!sharedslot)
+-			xenvif_idx_release(queue,
+-					   XENVIF_TX_CB(skb)->pending_idx,
+-					   XEN_NETIF_RSP_OKAY);
+-
+ 		/* Invalidate preceding fragments of this skb. */
+ 		for (j = 0; j < i; j++) {
+ 			pending_idx = frag_get_pending_idx(&shinfo->frags[j]);
+@@ -801,7 +874,6 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
+ 				     unsigned *copy_ops,
+ 				     unsigned *map_ops)
+ {
+-	struct gnttab_map_grant_ref *gop = queue->tx_map_ops;
+ 	struct sk_buff *skb, *nskb;
+ 	int ret;
+ 	unsigned int frag_overflow;
+@@ -883,8 +955,12 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
+ 			continue;
+ 		}
+ 
++		data_len = (txreq.size > XEN_NETBACK_TX_COPY_LEN) ?
++			XEN_NETBACK_TX_COPY_LEN : txreq.size;
++
+ 		ret = xenvif_count_requests(queue, &txreq, extra_count,
+ 					    txfrags, work_to_do);
++
+ 		if (unlikely(ret < 0))
+ 			break;
+ 
+@@ -910,9 +986,8 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
+ 		index = pending_index(queue->pending_cons);
+ 		pending_idx = queue->pending_ring[index];
+ 
+-		data_len = (txreq.size > XEN_NETBACK_TX_COPY_LEN &&
+-			    ret < XEN_NETBK_LEGACY_SLOTS_MAX) ?
+-			XEN_NETBACK_TX_COPY_LEN : txreq.size;
++		if (ret >= XEN_NETBK_LEGACY_SLOTS_MAX - 1 && data_len < txreq.size)
++			data_len = txreq.size;
+ 
+ 		skb = xenvif_alloc_skb(data_len);
+ 		if (unlikely(skb == NULL)) {
+@@ -923,8 +998,6 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
+ 		}
+ 
+ 		skb_shinfo(skb)->nr_frags = ret;
+-		if (data_len < txreq.size)
+-			skb_shinfo(skb)->nr_frags++;
+ 		/* At this point shinfo->nr_frags is in fact the number of
+ 		 * slots, which can be as large as XEN_NETBK_LEGACY_SLOTS_MAX.
+ 		 */
+@@ -986,54 +1059,19 @@ static void xenvif_tx_build_gops(struct xenvif_queue *queue,
+ 					     type);
+ 		}
+ 
+-		XENVIF_TX_CB(skb)->pending_idx = pending_idx;
+-
+-		__skb_put(skb, data_len);
+-		queue->tx_copy_ops[*copy_ops].source.u.ref = txreq.gref;
+-		queue->tx_copy_ops[*copy_ops].source.domid = queue->vif->domid;
+-		queue->tx_copy_ops[*copy_ops].source.offset = txreq.offset;
+-
+-		queue->tx_copy_ops[*copy_ops].dest.u.gmfn =
+-			virt_to_gfn(skb->data);
+-		queue->tx_copy_ops[*copy_ops].dest.domid = DOMID_SELF;
+-		queue->tx_copy_ops[*copy_ops].dest.offset =
+-			offset_in_page(skb->data) & ~XEN_PAGE_MASK;
+-
+-		queue->tx_copy_ops[*copy_ops].len = data_len;
+-		queue->tx_copy_ops[*copy_ops].flags = GNTCOPY_source_gref;
+-
+-		(*copy_ops)++;
+-
+-		if (data_len < txreq.size) {
+-			frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
+-					     pending_idx);
+-			xenvif_tx_create_map_op(queue, pending_idx, &txreq,
+-						extra_count, gop);
+-			gop++;
+-		} else {
+-			frag_set_pending_idx(&skb_shinfo(skb)->frags[0],
+-					     INVALID_PENDING_IDX);
+-			memcpy(&queue->pending_tx_info[pending_idx].req,
+-			       &txreq, sizeof(txreq));
+-			queue->pending_tx_info[pending_idx].extra_count =
+-				extra_count;
+-		}
+-
+-		queue->pending_cons++;
+-
+-		gop = xenvif_get_requests(queue, skb, txfrags, gop,
+-				          frag_overflow, nskb);
++		xenvif_get_requests(queue, skb, &txreq, txfrags, copy_ops,
++				    map_ops, frag_overflow, nskb, extra_count,
++				    data_len);
+ 
+ 		__skb_queue_tail(&queue->tx_queue, skb);
+ 
+ 		queue->tx.req_cons = idx;
+ 
+-		if (((gop-queue->tx_map_ops) >= ARRAY_SIZE(queue->tx_map_ops)) ||
++		if ((*map_ops >= ARRAY_SIZE(queue->tx_map_ops)) ||
+ 		    (*copy_ops >= ARRAY_SIZE(queue->tx_copy_ops)))
+ 			break;
+ 	}
+ 
+-	(*map_ops) = gop - queue->tx_map_ops;
+ 	return;
+ }
+ 
+@@ -1112,9 +1150,8 @@ static int xenvif_tx_submit(struct xenvif_queue *queue)
+ 	while ((skb = __skb_dequeue(&queue->tx_queue)) != NULL) {
+ 		struct xen_netif_tx_request *txp;
+ 		u16 pending_idx;
+-		unsigned data_len;
+ 
+-		pending_idx = XENVIF_TX_CB(skb)->pending_idx;
++		pending_idx = copy_pending_idx(skb, 0);
+ 		txp = &queue->pending_tx_info[pending_idx].req;
+ 
+ 		/* Check the remap error code. */
+@@ -1133,18 +1170,6 @@ static int xenvif_tx_submit(struct xenvif_queue *queue)
+ 			continue;
+ 		}
+ 
+-		data_len = skb->len;
+-		callback_param(queue, pending_idx).ctx = NULL;
+-		if (data_len < txp->size) {
+-			/* Append the packet payload as a fragment. */
+-			txp->offset += data_len;
+-			txp->size -= data_len;
+-		} else {
+-			/* Schedule a response immediately. */
+-			xenvif_idx_release(queue, pending_idx,
+-					   XEN_NETIF_RSP_OKAY);
+-		}
+-
+ 		if (txp->flags & XEN_NETTXF_csum_blank)
+ 			skb->ip_summed = CHECKSUM_PARTIAL;
+ 		else if (txp->flags & XEN_NETTXF_data_validated)
+@@ -1331,7 +1356,7 @@ static inline void xenvif_tx_dealloc_action(struct xenvif_queue *queue)
+ /* Called after netfront has transmitted */
+ int xenvif_tx_action(struct xenvif_queue *queue, int budget)
+ {
+-	unsigned nr_mops, nr_cops = 0;
++	unsigned nr_mops = 0, nr_cops = 0;
+ 	int work_done, ret;
+ 
+ 	if (unlikely(!tx_work_todo(queue)))
+@@ -1418,7 +1443,7 @@ static void push_tx_responses(struct xenvif_queue *queue)
+ 		notify_remote_via_irq(queue->tx_irq);
+ }
+ 
+-void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx)
++static void xenvif_idx_unmap(struct xenvif_queue *queue, u16 pending_idx)
+ {
+ 	int ret;
+ 	struct gnttab_unmap_grant_ref tx_unmap_op;
+diff --git a/drivers/net/xen-netback/rx.c b/drivers/net/xen-netback/rx.c
+index a0335407be423..0ba754ebc5baa 100644
+--- a/drivers/net/xen-netback/rx.c
++++ b/drivers/net/xen-netback/rx.c
+@@ -82,9 +82,10 @@ static bool xenvif_rx_ring_slots_available(struct xenvif_queue *queue)
+ 	return false;
+ }
+ 
+-void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb)
++bool xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb)
+ {
+ 	unsigned long flags;
++	bool ret = true;
+ 
+ 	spin_lock_irqsave(&queue->rx_queue.lock, flags);
+ 
+@@ -92,8 +93,7 @@ void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb)
+ 		struct net_device *dev = queue->vif->dev;
+ 
+ 		netif_tx_stop_queue(netdev_get_tx_queue(dev, queue->id));
+-		kfree_skb(skb);
+-		queue->vif->dev->stats.rx_dropped++;
++		ret = false;
+ 	} else {
+ 		if (skb_queue_empty(&queue->rx_queue))
+ 			xenvif_update_needed_slots(queue, skb);
+@@ -104,6 +104,8 @@ void xenvif_rx_queue_tail(struct xenvif_queue *queue, struct sk_buff *skb)
+ 	}
+ 
+ 	spin_unlock_irqrestore(&queue->rx_queue.lock, flags);
++
++	return ret;
+ }
+ 
+ static struct sk_buff *xenvif_rx_dequeue(struct xenvif_queue *queue)
+@@ -486,7 +488,7 @@ static void xenvif_rx_skb(struct xenvif_queue *queue)
+ 
+ #define RX_BATCH_SIZE 64
+ 
+-void xenvif_rx_action(struct xenvif_queue *queue)
++static void xenvif_rx_action(struct xenvif_queue *queue)
+ {
+ 	struct sk_buff_head completed_skbs;
+ 	unsigned int work_done = 0;
+diff --git a/drivers/net/xen-netfront.c b/drivers/net/xen-netfront.c
+index 074dceb1930b3..6e73d3a00eecd 100644
+--- a/drivers/net/xen-netfront.c
++++ b/drivers/net/xen-netfront.c
+@@ -1866,6 +1866,12 @@ static int netfront_resume(struct xenbus_device *dev)
+ 	netif_tx_unlock_bh(info->netdev);
+ 
+ 	xennet_disconnect_backend(info);
++
++	rtnl_lock();
++	if (info->queues)
++		xennet_destroy_queues(info);
++	rtnl_unlock();
++
+ 	return 0;
+ }
+ 
+diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
+index 694373951b18a..692ee0f4a1ec3 100644
+--- a/drivers/nvme/host/core.c
++++ b/drivers/nvme/host/core.c
+@@ -2921,10 +2921,6 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
+ 	if (!ctrl->identified) {
+ 		unsigned int i;
+ 
+-		ret = nvme_init_subsystem(ctrl, id);
+-		if (ret)
+-			goto out_free;
+-
+ 		/*
+ 		 * Check for quirks.  Quirk can depend on firmware version,
+ 		 * so, in principle, the set of quirks present can change
+@@ -2937,6 +2933,10 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
+ 			if (quirk_matches(id, &core_quirks[i]))
+ 				ctrl->quirks |= core_quirks[i].quirks;
+ 		}
++
++		ret = nvme_init_subsystem(ctrl, id);
++		if (ret)
++			goto out_free;
+ 	}
+ 	memcpy(ctrl->subsys->firmware_rev, id->fr,
+ 	       sizeof(ctrl->subsys->firmware_rev));
+diff --git a/drivers/regulator/slg51000-regulator.c b/drivers/regulator/slg51000-regulator.c
+index 75a941fb3c2bd..1b2eee95ad3f9 100644
+--- a/drivers/regulator/slg51000-regulator.c
++++ b/drivers/regulator/slg51000-regulator.c
+@@ -457,6 +457,8 @@ static int slg51000_i2c_probe(struct i2c_client *client)
+ 		chip->cs_gpiod = cs_gpiod;
+ 	}
+ 
++	usleep_range(10000, 11000);
++
+ 	i2c_set_clientdata(client, chip);
+ 	chip->chip_irq = client->irq;
+ 	chip->dev = dev;
+diff --git a/drivers/regulator/twl6030-regulator.c b/drivers/regulator/twl6030-regulator.c
+index 7c7e3648ea4bf..f3856750944f4 100644
+--- a/drivers/regulator/twl6030-regulator.c
++++ b/drivers/regulator/twl6030-regulator.c
+@@ -67,6 +67,7 @@ struct twlreg_info {
+ #define TWL6030_CFG_STATE_SLEEP	0x03
+ #define TWL6030_CFG_STATE_GRP_SHIFT	5
+ #define TWL6030_CFG_STATE_APP_SHIFT	2
++#define TWL6030_CFG_STATE_MASK		0x03
+ #define TWL6030_CFG_STATE_APP_MASK	(0x03 << TWL6030_CFG_STATE_APP_SHIFT)
+ #define TWL6030_CFG_STATE_APP(v)	(((v) & TWL6030_CFG_STATE_APP_MASK) >>\
+ 						TWL6030_CFG_STATE_APP_SHIFT)
+@@ -128,13 +129,14 @@ static int twl6030reg_is_enabled(struct regulator_dev *rdev)
+ 		if (grp < 0)
+ 			return grp;
+ 		grp &= P1_GRP_6030;
++		val = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_STATE);
++		val = TWL6030_CFG_STATE_APP(val);
+ 	} else {
++		val = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_STATE);
++		val &= TWL6030_CFG_STATE_MASK;
+ 		grp = 1;
+ 	}
+ 
+-	val = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_STATE);
+-	val = TWL6030_CFG_STATE_APP(val);
+-
+ 	return grp && (val == TWL6030_CFG_STATE_ON);
+ }
+ 
+@@ -187,7 +189,12 @@ static int twl6030reg_get_status(struct regulator_dev *rdev)
+ 
+ 	val = twlreg_read(info, TWL_MODULE_PM_RECEIVER, VREG_STATE);
+ 
+-	switch (TWL6030_CFG_STATE_APP(val)) {
++	if (info->features & TWL6032_SUBCLASS)
++		val &= TWL6030_CFG_STATE_MASK;
++	else
++		val = TWL6030_CFG_STATE_APP(val);
++
++	switch (val) {
+ 	case TWL6030_CFG_STATE_ON:
+ 		return REGULATOR_STATUS_NORMAL;
+ 
+diff --git a/drivers/rtc/rtc-cmos.c b/drivers/rtc/rtc-cmos.c
+index b90a603d6b12f..7c006c2b125f8 100644
+--- a/drivers/rtc/rtc-cmos.c
++++ b/drivers/rtc/rtc-cmos.c
+@@ -249,10 +249,46 @@ static int cmos_set_time(struct device *dev, struct rtc_time *t)
+ 	return mc146818_set_time(t);
+ }
+ 
++struct cmos_read_alarm_callback_param {
++	struct cmos_rtc *cmos;
++	struct rtc_time *time;
++	unsigned char	rtc_control;
++};
++
++static void cmos_read_alarm_callback(unsigned char __always_unused seconds,
++				     void *param_in)
++{
++	struct cmos_read_alarm_callback_param *p =
++		(struct cmos_read_alarm_callback_param *)param_in;
++	struct rtc_time *time = p->time;
++
++	time->tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
++	time->tm_min = CMOS_READ(RTC_MINUTES_ALARM);
++	time->tm_hour = CMOS_READ(RTC_HOURS_ALARM);
++
++	if (p->cmos->day_alrm) {
++		/* ignore upper bits on readback per ACPI spec */
++		time->tm_mday = CMOS_READ(p->cmos->day_alrm) & 0x3f;
++		if (!time->tm_mday)
++			time->tm_mday = -1;
++
++		if (p->cmos->mon_alrm) {
++			time->tm_mon = CMOS_READ(p->cmos->mon_alrm);
++			if (!time->tm_mon)
++				time->tm_mon = -1;
++		}
++	}
++
++	p->rtc_control = CMOS_READ(RTC_CONTROL);
++}
++
+ static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
+ {
+ 	struct cmos_rtc	*cmos = dev_get_drvdata(dev);
+-	unsigned char	rtc_control;
++	struct cmos_read_alarm_callback_param p = {
++		.cmos = cmos,
++		.time = &t->time,
++	};
+ 
+ 	/* This not only a rtc_op, but also called directly */
+ 	if (!is_valid_irq(cmos->irq))
+@@ -263,28 +299,18 @@ static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
+ 	 * the future.
+ 	 */
+ 
+-	spin_lock_irq(&rtc_lock);
+-	t->time.tm_sec = CMOS_READ(RTC_SECONDS_ALARM);
+-	t->time.tm_min = CMOS_READ(RTC_MINUTES_ALARM);
+-	t->time.tm_hour = CMOS_READ(RTC_HOURS_ALARM);
+-
+-	if (cmos->day_alrm) {
+-		/* ignore upper bits on readback per ACPI spec */
+-		t->time.tm_mday = CMOS_READ(cmos->day_alrm) & 0x3f;
+-		if (!t->time.tm_mday)
+-			t->time.tm_mday = -1;
+-
+-		if (cmos->mon_alrm) {
+-			t->time.tm_mon = CMOS_READ(cmos->mon_alrm);
+-			if (!t->time.tm_mon)
+-				t->time.tm_mon = -1;
+-		}
+-	}
+-
+-	rtc_control = CMOS_READ(RTC_CONTROL);
+-	spin_unlock_irq(&rtc_lock);
++	/* Some Intel chipsets disconnect the alarm registers when the clock
++	 * update is in progress - during this time reads return bogus values
++	 * and writes may fail silently. See for example "7th Generation Intel®
++	 * Processor Family I/O for U/Y Platforms [...] Datasheet", section
++	 * 27.7.1
++	 *
++	 * Use the mc146818_avoid_UIP() function to avoid this.
++	 */
++	if (!mc146818_avoid_UIP(cmos_read_alarm_callback, &p))
++		return -EIO;
+ 
+-	if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
++	if (!(p.rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
+ 		if (((unsigned)t->time.tm_sec) < 0x60)
+ 			t->time.tm_sec = bcd2bin(t->time.tm_sec);
+ 		else
+@@ -313,7 +339,7 @@ static int cmos_read_alarm(struct device *dev, struct rtc_wkalrm *t)
+ 		}
+ 	}
+ 
+-	t->enabled = !!(rtc_control & RTC_AIE);
++	t->enabled = !!(p.rtc_control & RTC_AIE);
+ 	t->pending = 0;
+ 
+ 	return 0;
+@@ -444,10 +470,57 @@ static int cmos_validate_alarm(struct device *dev, struct rtc_wkalrm *t)
+ 	return 0;
+ }
+ 
++struct cmos_set_alarm_callback_param {
++	struct cmos_rtc *cmos;
++	unsigned char mon, mday, hrs, min, sec;
++	struct rtc_wkalrm *t;
++};
++
++/* Note: this function may be executed by mc146818_avoid_UIP() more then
++ *	 once
++ */
++static void cmos_set_alarm_callback(unsigned char __always_unused seconds,
++				    void *param_in)
++{
++	struct cmos_set_alarm_callback_param *p =
++		(struct cmos_set_alarm_callback_param *)param_in;
++
++	/* next rtc irq must not be from previous alarm setting */
++	cmos_irq_disable(p->cmos, RTC_AIE);
++
++	/* update alarm */
++	CMOS_WRITE(p->hrs, RTC_HOURS_ALARM);
++	CMOS_WRITE(p->min, RTC_MINUTES_ALARM);
++	CMOS_WRITE(p->sec, RTC_SECONDS_ALARM);
++
++	/* the system may support an "enhanced" alarm */
++	if (p->cmos->day_alrm) {
++		CMOS_WRITE(p->mday, p->cmos->day_alrm);
++		if (p->cmos->mon_alrm)
++			CMOS_WRITE(p->mon, p->cmos->mon_alrm);
++	}
++
++	if (use_hpet_alarm()) {
++		/*
++		 * FIXME the HPET alarm glue currently ignores day_alrm
++		 * and mon_alrm ...
++		 */
++		hpet_set_alarm_time(p->t->time.tm_hour, p->t->time.tm_min,
++				    p->t->time.tm_sec);
++	}
++
++	if (p->t->enabled)
++		cmos_irq_enable(p->cmos, RTC_AIE);
++}
++
+ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
+ {
+ 	struct cmos_rtc	*cmos = dev_get_drvdata(dev);
+-	unsigned char mon, mday, hrs, min, sec, rtc_control;
++	struct cmos_set_alarm_callback_param p = {
++		.cmos = cmos,
++		.t = t
++	};
++	unsigned char rtc_control;
+ 	int ret;
+ 
+ 	/* This not only a rtc_op, but also called directly */
+@@ -458,11 +531,11 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
+ 	if (ret < 0)
+ 		return ret;
+ 
+-	mon = t->time.tm_mon + 1;
+-	mday = t->time.tm_mday;
+-	hrs = t->time.tm_hour;
+-	min = t->time.tm_min;
+-	sec = t->time.tm_sec;
++	p.mon = t->time.tm_mon + 1;
++	p.mday = t->time.tm_mday;
++	p.hrs = t->time.tm_hour;
++	p.min = t->time.tm_min;
++	p.sec = t->time.tm_sec;
+ 
+ 	spin_lock_irq(&rtc_lock);
+ 	rtc_control = CMOS_READ(RTC_CONTROL);
+@@ -470,43 +543,21 @@ static int cmos_set_alarm(struct device *dev, struct rtc_wkalrm *t)
+ 
+ 	if (!(rtc_control & RTC_DM_BINARY) || RTC_ALWAYS_BCD) {
+ 		/* Writing 0xff means "don't care" or "match all".  */
+-		mon = (mon <= 12) ? bin2bcd(mon) : 0xff;
+-		mday = (mday >= 1 && mday <= 31) ? bin2bcd(mday) : 0xff;
+-		hrs = (hrs < 24) ? bin2bcd(hrs) : 0xff;
+-		min = (min < 60) ? bin2bcd(min) : 0xff;
+-		sec = (sec < 60) ? bin2bcd(sec) : 0xff;
+-	}
+-
+-	spin_lock_irq(&rtc_lock);
+-
+-	/* next rtc irq must not be from previous alarm setting */
+-	cmos_irq_disable(cmos, RTC_AIE);
+-
+-	/* update alarm */
+-	CMOS_WRITE(hrs, RTC_HOURS_ALARM);
+-	CMOS_WRITE(min, RTC_MINUTES_ALARM);
+-	CMOS_WRITE(sec, RTC_SECONDS_ALARM);
+-
+-	/* the system may support an "enhanced" alarm */
+-	if (cmos->day_alrm) {
+-		CMOS_WRITE(mday, cmos->day_alrm);
+-		if (cmos->mon_alrm)
+-			CMOS_WRITE(mon, cmos->mon_alrm);
+-	}
+-
+-	if (use_hpet_alarm()) {
+-		/*
+-		 * FIXME the HPET alarm glue currently ignores day_alrm
+-		 * and mon_alrm ...
+-		 */
+-		hpet_set_alarm_time(t->time.tm_hour, t->time.tm_min,
+-				    t->time.tm_sec);
++		p.mon = (p.mon <= 12) ? bin2bcd(p.mon) : 0xff;
++		p.mday = (p.mday >= 1 && p.mday <= 31) ? bin2bcd(p.mday) : 0xff;
++		p.hrs = (p.hrs < 24) ? bin2bcd(p.hrs) : 0xff;
++		p.min = (p.min < 60) ? bin2bcd(p.min) : 0xff;
++		p.sec = (p.sec < 60) ? bin2bcd(p.sec) : 0xff;
+ 	}
+ 
+-	if (t->enabled)
+-		cmos_irq_enable(cmos, RTC_AIE);
+-
+-	spin_unlock_irq(&rtc_lock);
++	/*
++	 * Some Intel chipsets disconnect the alarm registers when the clock
++	 * update is in progress - during this time writes fail silently.
++	 *
++	 * Use mc146818_avoid_UIP() to avoid this.
++	 */
++	if (!mc146818_avoid_UIP(cmos_set_alarm_callback, &p))
++		return -EIO;
+ 
+ 	cmos->alarm_expires = rtc_tm_to_time64(&t->time);
+ 
+diff --git a/drivers/rtc/rtc-mc146818-lib.c b/drivers/rtc/rtc-mc146818-lib.c
+index f3f5a87fe376e..347655d24b5d3 100644
+--- a/drivers/rtc/rtc-mc146818-lib.c
++++ b/drivers/rtc/rtc-mc146818-lib.c
+@@ -8,6 +8,76 @@
+ #include <linux/acpi.h>
+ #endif
+ 
++/*
++ * Execute a function while the UIP (Update-in-progress) bit of the RTC is
++ * unset.
++ *
++ * Warning: callback may be executed more then once.
++ */
++bool mc146818_avoid_UIP(void (*callback)(unsigned char seconds, void *param),
++			void *param)
++{
++	int i;
++	unsigned long flags;
++	unsigned char seconds;
++
++	for (i = 0; i < 10; i++) {
++		spin_lock_irqsave(&rtc_lock, flags);
++
++		/*
++		 * Check whether there is an update in progress during which the
++		 * readout is unspecified. The maximum update time is ~2ms. Poll
++		 * every msec for completion.
++		 *
++		 * Store the second value before checking UIP so a long lasting
++		 * NMI which happens to hit after the UIP check cannot make
++		 * an update cycle invisible.
++		 */
++		seconds = CMOS_READ(RTC_SECONDS);
++
++		if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP) {
++			spin_unlock_irqrestore(&rtc_lock, flags);
++			mdelay(1);
++			continue;
++		}
++
++		/* Revalidate the above readout */
++		if (seconds != CMOS_READ(RTC_SECONDS)) {
++			spin_unlock_irqrestore(&rtc_lock, flags);
++			continue;
++		}
++
++		if (callback)
++			callback(seconds, param);
++
++		/*
++		 * Check for the UIP bit again. If it is set now then
++		 * the above values may contain garbage.
++		 */
++		if (CMOS_READ(RTC_FREQ_SELECT) & RTC_UIP) {
++			spin_unlock_irqrestore(&rtc_lock, flags);
++			mdelay(1);
++			continue;
++		}
++
++		/*
++		 * A NMI might have interrupted the above sequence so check
++		 * whether the seconds value has changed which indicates that
++		 * the NMI took longer than the UIP bit was set. Unlikely, but
++		 * possible and there is also virt...
++		 */
++		if (seconds != CMOS_READ(RTC_SECONDS)) {
++			spin_unlock_irqrestore(&rtc_lock, flags);
++			continue;
++		}
++		spin_unlock_irqrestore(&rtc_lock, flags);
++
++		return true;
++	}
++	return false;
++}
++EXPORT_SYMBOL_GPL(mc146818_avoid_UIP);
++
+ /*
+  * If the UIP (Update-in-progress) bit of the RTC is set for more then
+  * 10ms, the RTC is apparently broken or not present.
+diff --git a/drivers/s390/net/qeth_l2_main.c b/drivers/s390/net/qeth_l2_main.c
+index dc6c00768d919..d694e3ff80865 100644
+--- a/drivers/s390/net/qeth_l2_main.c
++++ b/drivers/s390/net/qeth_l2_main.c
+@@ -661,13 +661,13 @@ static void qeth_l2_dev2br_fdb_notify(struct qeth_card *card, u8 code,
+ 					 card->dev, &info.info, NULL);
+ 		QETH_CARD_TEXT(card, 4, "andelmac");
+ 		QETH_CARD_TEXT_(card, 4,
+-				"mc%012lx", ether_addr_to_u64(ntfy_mac));
++				"mc%012llx", ether_addr_to_u64(ntfy_mac));
+ 	} else {
+ 		call_switchdev_notifiers(SWITCHDEV_FDB_ADD_TO_BRIDGE,
+ 					 card->dev, &info.info, NULL);
+ 		QETH_CARD_TEXT(card, 4, "anaddmac");
+ 		QETH_CARD_TEXT_(card, 4,
+-				"mc%012lx", ether_addr_to_u64(ntfy_mac));
++				"mc%012llx", ether_addr_to_u64(ntfy_mac));
+ 	}
+ }
+ 
+@@ -764,9 +764,8 @@ static void qeth_l2_br2dev_worker(struct work_struct *work)
+ 	struct list_head *iter;
+ 	int err = 0;
+ 
+-	kfree(br2dev_event_work);
+-	QETH_CARD_TEXT_(card, 4, "b2dw%04x", event);
+-	QETH_CARD_TEXT_(card, 4, "ma%012lx", ether_addr_to_u64(addr));
++	QETH_CARD_TEXT_(card, 4, "b2dw%04lx", event);
++	QETH_CARD_TEXT_(card, 4, "ma%012llx", ether_addr_to_u64(addr));
+ 
+ 	rcu_read_lock();
+ 	/* Verify preconditions are still valid: */
+@@ -795,7 +794,7 @@ static void qeth_l2_br2dev_worker(struct work_struct *work)
+ 				if (err) {
+ 					QETH_CARD_TEXT(card, 2, "b2derris");
+ 					QETH_CARD_TEXT_(card, 2,
+-							"err%02x%03d", event,
++							"err%02lx%03d", event,
+ 							lowerdev->ifindex);
+ 				}
+ 			}
+@@ -813,7 +812,7 @@ static void qeth_l2_br2dev_worker(struct work_struct *work)
+ 			break;
+ 		}
+ 		if (err)
+-			QETH_CARD_TEXT_(card, 2, "b2derr%02x", event);
++			QETH_CARD_TEXT_(card, 2, "b2derr%02lx", event);
+ 	}
+ 
+ unlock:
+@@ -821,6 +820,7 @@ unlock:
+ 	dev_put(brdev);
+ 	dev_put(lsyncdev);
+ 	dev_put(dstdev);
++	kfree(br2dev_event_work);
+ }
+ 
+ static int qeth_l2_br2dev_queue_work(struct net_device *brdev,
+@@ -878,7 +878,7 @@ static int qeth_l2_switchdev_event(struct notifier_block *unused,
+ 	while (lowerdev) {
+ 		if (qeth_l2_must_learn(lowerdev, dstdev)) {
+ 			card = lowerdev->ml_priv;
+-			QETH_CARD_TEXT_(card, 4, "b2dqw%03x", event);
++			QETH_CARD_TEXT_(card, 4, "b2dqw%03lx", event);
+ 			rc = qeth_l2_br2dev_queue_work(brdev, lowerdev,
+ 						       dstdev, event,
+ 						       fdb_info->addr);
+diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c
+index 89ee033f0c353..bbb57b9f6e01e 100644
+--- a/drivers/soundwire/intel.c
++++ b/drivers/soundwire/intel.c
+@@ -1285,6 +1285,7 @@ static int intel_link_probe(struct auxiliary_device *auxdev,
+ 	cdns->msg_count = 0;
+ 
+ 	bus->link_id = auxdev->id;
++	bus->clk_stop_timeout = 1;
+ 
+ 	sdw_cdns_probe(cdns);
+ 
+diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c
+index 2ca19b01948a2..49acba1dea1e7 100644
+--- a/drivers/spi/spi-mt65xx.c
++++ b/drivers/spi/spi-mt65xx.c
+@@ -912,14 +912,20 @@ static int mtk_spi_remove(struct platform_device *pdev)
+ {
+ 	struct spi_master *master = platform_get_drvdata(pdev);
+ 	struct mtk_spi *mdata = spi_master_get_devdata(master);
++	int ret;
+ 
+-	pm_runtime_disable(&pdev->dev);
++	ret = pm_runtime_resume_and_get(&pdev->dev);
++	if (ret < 0)
++		return ret;
+ 
+ 	mtk_spi_reset(mdata);
+ 
+ 	if (mdata->dev_comp->no_need_unprepare)
+ 		clk_unprepare(mdata->spi_clk);
+ 
++	pm_runtime_put_noidle(&pdev->dev);
++	pm_runtime_disable(&pdev->dev);
++
+ 	return 0;
+ }
+ 
+diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c
+index dfa1d9eedde1a..4812ba4bbedd7 100644
+--- a/drivers/usb/dwc3/gadget.c
++++ b/drivers/usb/dwc3/gadget.c
+@@ -291,7 +291,8 @@ int dwc3_send_gadget_ep_cmd(struct dwc3_ep *dep, unsigned int cmd,
+ 	 *
+ 	 * DWC_usb3 3.30a and DWC_usb31 1.90a programming guide section 3.2.2
+ 	 */
+-	if (dwc->gadget->speed <= USB_SPEED_HIGH) {
++	if (dwc->gadget->speed <= USB_SPEED_HIGH ||
++	    DWC3_DEPCMD_CMD(cmd) == DWC3_DEPCMD_ENDTRANSFER) {
+ 		reg = dwc3_readl(dwc->regs, DWC3_GUSB2PHYCFG(0));
+ 		if (unlikely(reg & DWC3_GUSB2PHYCFG_SUSPHY)) {
+ 			saved_config |= DWC3_GUSB2PHYCFG_SUSPHY;
+diff --git a/drivers/video/fbdev/core/fbcon.c b/drivers/video/fbdev/core/fbcon.c
+index e035a63bbe5b7..1f37904b0405e 100644
+--- a/drivers/video/fbdev/core/fbcon.c
++++ b/drivers/video/fbdev/core/fbcon.c
+@@ -601,7 +601,7 @@ static void fbcon_prepare_logo(struct vc_data *vc, struct fb_info *info,
+ 		if (scr_readw(r) != vc->vc_video_erase_char)
+ 			break;
+ 	if (r != q && new_rows >= rows + logo_lines) {
+-		save = kmalloc(array3_size(logo_lines, new_cols, 2),
++		save = kzalloc(array3_size(logo_lines, new_cols, 2),
+ 			       GFP_KERNEL);
+ 		if (save) {
+ 			int i = cols < new_cols ? cols : new_cols;
+diff --git a/fs/Makefile b/fs/Makefile
+index 84c5e4cdfee5a..d504be65a210a 100644
+--- a/fs/Makefile
++++ b/fs/Makefile
+@@ -32,8 +32,6 @@ obj-$(CONFIG_TIMERFD)		+= timerfd.o
+ obj-$(CONFIG_EVENTFD)		+= eventfd.o
+ obj-$(CONFIG_USERFAULTFD)	+= userfaultfd.o
+ obj-$(CONFIG_AIO)               += aio.o
+-obj-$(CONFIG_IO_URING)		+= io_uring.o
+-obj-$(CONFIG_IO_WQ)		+= io-wq.o
+ obj-$(CONFIG_FS_DAX)		+= dax.o
+ obj-$(CONFIG_FS_ENCRYPTION)	+= crypto/
+ obj-$(CONFIG_FS_VERITY)		+= verity/
+diff --git a/fs/btrfs/send.c b/fs/btrfs/send.c
+index 4d2c6ce29fe58..9250a17731bdb 100644
+--- a/fs/btrfs/send.c
++++ b/fs/btrfs/send.c
+@@ -5398,6 +5398,7 @@ static int clone_range(struct send_ctx *sctx,
+ 		u64 ext_len;
+ 		u64 clone_len;
+ 		u64 clone_data_offset;
++		bool crossed_src_i_size = false;
+ 
+ 		if (slot >= btrfs_header_nritems(leaf)) {
+ 			ret = btrfs_next_leaf(clone_root->root, path);
+@@ -5454,8 +5455,10 @@ static int clone_range(struct send_ctx *sctx,
+ 		if (key.offset >= clone_src_i_size)
+ 			break;
+ 
+-		if (key.offset + ext_len > clone_src_i_size)
++		if (key.offset + ext_len > clone_src_i_size) {
+ 			ext_len = clone_src_i_size - key.offset;
++			crossed_src_i_size = true;
++		}
+ 
+ 		clone_data_offset = btrfs_file_extent_offset(leaf, ei);
+ 		if (btrfs_file_extent_disk_bytenr(leaf, ei) == disk_byte) {
+@@ -5515,6 +5518,25 @@ static int clone_range(struct send_ctx *sctx,
+ 				ret = send_clone(sctx, offset, clone_len,
+ 						 clone_root);
+ 			}
++		} else if (crossed_src_i_size && clone_len < len) {
++			/*
++			 * If we are at i_size of the clone source inode and we
++			 * can not clone from it, terminate the loop. This is
++			 * to avoid sending two write operations, one with a
++			 * length matching clone_len and the final one after
++			 * this loop with a length of len - clone_len.
++			 *
++			 * When using encoded writes (BTRFS_SEND_FLAG_COMPRESSED
++			 * was passed to the send ioctl), this helps avoid
++			 * sending an encoded write for an offset that is not
++			 * sector size aligned, in case the i_size of the source
++			 * inode is not sector size aligned. That will make the
++			 * receiver fallback to decompression of the data and
++			 * writing it using regular buffered IO, therefore while
++			 * not incorrect, it's not optimal due decompression and
++			 * possible re-compression at the receiver.
++			 */
++			break;
+ 		} else {
+ 			ret = send_extent_data(sctx, offset, clone_len);
+ 		}
+diff --git a/fs/cifs/connect.c b/fs/cifs/connect.c
+index c6e2a0ff8f0c6..a4284c4d7e031 100644
+--- a/fs/cifs/connect.c
++++ b/fs/cifs/connect.c
+@@ -1392,6 +1392,7 @@ cifs_put_tcp_session(struct TCP_Server_Info *server, int from_reconnect)
+ 	server->session_key.response = NULL;
+ 	server->session_key.len = 0;
+ 	kfree(server->hostname);
++	server->hostname = NULL;
+ 
+ 	task = xchg(&server->tsk, NULL);
+ 	if (task)
+diff --git a/fs/file.c b/fs/file.c
+index ee93173467025..214364e19d76f 100644
+--- a/fs/file.c
++++ b/fs/file.c
+@@ -1029,7 +1029,16 @@ static unsigned long __fget_light(unsigned int fd, fmode_t mask)
+ 	struct files_struct *files = current->files;
+ 	struct file *file;
+ 
+-	if (atomic_read(&files->count) == 1) {
++	/*
++	 * If another thread is concurrently calling close_fd() followed
++	 * by put_files_struct(), we must not observe the old table
++	 * entry combined with the new refcount - otherwise we could
++	 * return a file that is concurrently being freed.
++	 *
++	 * atomic_read_acquire() pairs with atomic_dec_and_test() in
++	 * put_files_struct().
++	 */
++	if (atomic_read_acquire(&files->count) == 1) {
+ 		file = files_lookup_fd_raw(files, fd);
+ 		if (!file || unlikely(file->f_mode & mask))
+ 			return 0;
+diff --git a/fs/io-wq.c b/fs/io-wq.c
+deleted file mode 100644
+index 6031fb319d878..0000000000000
+--- a/fs/io-wq.c
++++ /dev/null
+@@ -1,1398 +0,0 @@
+-// SPDX-License-Identifier: GPL-2.0
+-/*
+- * Basic worker thread pool for io_uring
+- *
+- * Copyright (C) 2019 Jens Axboe
+- *
+- */
+-#include <linux/kernel.h>
+-#include <linux/init.h>
+-#include <linux/errno.h>
+-#include <linux/sched/signal.h>
+-#include <linux/percpu.h>
+-#include <linux/slab.h>
+-#include <linux/rculist_nulls.h>
+-#include <linux/cpu.h>
+-#include <linux/tracehook.h>
+-#include <uapi/linux/io_uring.h>
+-
+-#include "io-wq.h"
+-
+-#define WORKER_IDLE_TIMEOUT	(5 * HZ)
+-
+-enum {
+-	IO_WORKER_F_UP		= 1,	/* up and active */
+-	IO_WORKER_F_RUNNING	= 2,	/* account as running */
+-	IO_WORKER_F_FREE	= 4,	/* worker on free list */
+-	IO_WORKER_F_BOUND	= 8,	/* is doing bounded work */
+-};
+-
+-enum {
+-	IO_WQ_BIT_EXIT		= 0,	/* wq exiting */
+-};
+-
+-enum {
+-	IO_ACCT_STALLED_BIT	= 0,	/* stalled on hash */
+-};
+-
+-/*
+- * One for each thread in a wqe pool
+- */
+-struct io_worker {
+-	refcount_t ref;
+-	unsigned flags;
+-	struct hlist_nulls_node nulls_node;
+-	struct list_head all_list;
+-	struct task_struct *task;
+-	struct io_wqe *wqe;
+-
+-	struct io_wq_work *cur_work;
+-	spinlock_t lock;
+-
+-	struct completion ref_done;
+-
+-	unsigned long create_state;
+-	struct callback_head create_work;
+-	int create_index;
+-
+-	union {
+-		struct rcu_head rcu;
+-		struct work_struct work;
+-	};
+-};
+-
+-#if BITS_PER_LONG == 64
+-#define IO_WQ_HASH_ORDER	6
+-#else
+-#define IO_WQ_HASH_ORDER	5
+-#endif
+-
+-#define IO_WQ_NR_HASH_BUCKETS	(1u << IO_WQ_HASH_ORDER)
+-
+-struct io_wqe_acct {
+-	unsigned nr_workers;
+-	unsigned max_workers;
+-	int index;
+-	atomic_t nr_running;
+-	struct io_wq_work_list work_list;
+-	unsigned long flags;
+-};
+-
+-enum {
+-	IO_WQ_ACCT_BOUND,
+-	IO_WQ_ACCT_UNBOUND,
+-	IO_WQ_ACCT_NR,
+-};
+-
+-/*
+- * Per-node worker thread pool
+- */
+-struct io_wqe {
+-	raw_spinlock_t lock;
+-	struct io_wqe_acct acct[2];
+-
+-	int node;
+-
+-	struct hlist_nulls_head free_list;
+-	struct list_head all_list;
+-
+-	struct wait_queue_entry wait;
+-
+-	struct io_wq *wq;
+-	struct io_wq_work *hash_tail[IO_WQ_NR_HASH_BUCKETS];
+-
+-	cpumask_var_t cpu_mask;
+-};
+-
+-/*
+- * Per io_wq state
+-  */
+-struct io_wq {
+-	unsigned long state;
+-
+-	free_work_fn *free_work;
+-	io_wq_work_fn *do_work;
+-
+-	struct io_wq_hash *hash;
+-
+-	atomic_t worker_refs;
+-	struct completion worker_done;
+-
+-	struct hlist_node cpuhp_node;
+-
+-	struct task_struct *task;
+-
+-	struct io_wqe *wqes[];
+-};
+-
+-static enum cpuhp_state io_wq_online;
+-
+-struct io_cb_cancel_data {
+-	work_cancel_fn *fn;
+-	void *data;
+-	int nr_running;
+-	int nr_pending;
+-	bool cancel_all;
+-};
+-
+-static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index);
+-static void io_wqe_dec_running(struct io_worker *worker);
+-static bool io_acct_cancel_pending_work(struct io_wqe *wqe,
+-					struct io_wqe_acct *acct,
+-					struct io_cb_cancel_data *match);
+-static void create_worker_cb(struct callback_head *cb);
+-static void io_wq_cancel_tw_create(struct io_wq *wq);
+-
+-static bool io_worker_get(struct io_worker *worker)
+-{
+-	return refcount_inc_not_zero(&worker->ref);
+-}
+-
+-static void io_worker_release(struct io_worker *worker)
+-{
+-	if (refcount_dec_and_test(&worker->ref))
+-		complete(&worker->ref_done);
+-}
+-
+-static inline struct io_wqe_acct *io_get_acct(struct io_wqe *wqe, bool bound)
+-{
+-	return &wqe->acct[bound ? IO_WQ_ACCT_BOUND : IO_WQ_ACCT_UNBOUND];
+-}
+-
+-static inline struct io_wqe_acct *io_work_get_acct(struct io_wqe *wqe,
+-						   struct io_wq_work *work)
+-{
+-	return io_get_acct(wqe, !(work->flags & IO_WQ_WORK_UNBOUND));
+-}
+-
+-static inline struct io_wqe_acct *io_wqe_get_acct(struct io_worker *worker)
+-{
+-	return io_get_acct(worker->wqe, worker->flags & IO_WORKER_F_BOUND);
+-}
+-
+-static void io_worker_ref_put(struct io_wq *wq)
+-{
+-	if (atomic_dec_and_test(&wq->worker_refs))
+-		complete(&wq->worker_done);
+-}
+-
+-static void io_worker_cancel_cb(struct io_worker *worker)
+-{
+-	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
+-	struct io_wqe *wqe = worker->wqe;
+-	struct io_wq *wq = wqe->wq;
+-
+-	atomic_dec(&acct->nr_running);
+-	raw_spin_lock(&worker->wqe->lock);
+-	acct->nr_workers--;
+-	raw_spin_unlock(&worker->wqe->lock);
+-	io_worker_ref_put(wq);
+-	clear_bit_unlock(0, &worker->create_state);
+-	io_worker_release(worker);
+-}
+-
+-static bool io_task_worker_match(struct callback_head *cb, void *data)
+-{
+-	struct io_worker *worker;
+-
+-	if (cb->func != create_worker_cb)
+-		return false;
+-	worker = container_of(cb, struct io_worker, create_work);
+-	return worker == data;
+-}
+-
+-static void io_worker_exit(struct io_worker *worker)
+-{
+-	struct io_wqe *wqe = worker->wqe;
+-	struct io_wq *wq = wqe->wq;
+-
+-	while (1) {
+-		struct callback_head *cb = task_work_cancel_match(wq->task,
+-						io_task_worker_match, worker);
+-
+-		if (!cb)
+-			break;
+-		io_worker_cancel_cb(worker);
+-	}
+-
+-	if (refcount_dec_and_test(&worker->ref))
+-		complete(&worker->ref_done);
+-	wait_for_completion(&worker->ref_done);
+-
+-	raw_spin_lock(&wqe->lock);
+-	if (worker->flags & IO_WORKER_F_FREE)
+-		hlist_nulls_del_rcu(&worker->nulls_node);
+-	list_del_rcu(&worker->all_list);
+-	preempt_disable();
+-	io_wqe_dec_running(worker);
+-	worker->flags = 0;
+-	current->flags &= ~PF_IO_WORKER;
+-	preempt_enable();
+-	raw_spin_unlock(&wqe->lock);
+-
+-	kfree_rcu(worker, rcu);
+-	io_worker_ref_put(wqe->wq);
+-	do_exit(0);
+-}
+-
+-static inline bool io_acct_run_queue(struct io_wqe_acct *acct)
+-{
+-	if (!wq_list_empty(&acct->work_list) &&
+-	    !test_bit(IO_ACCT_STALLED_BIT, &acct->flags))
+-		return true;
+-	return false;
+-}
+-
+-/*
+- * Check head of free list for an available worker. If one isn't available,
+- * caller must create one.
+- */
+-static bool io_wqe_activate_free_worker(struct io_wqe *wqe,
+-					struct io_wqe_acct *acct)
+-	__must_hold(RCU)
+-{
+-	struct hlist_nulls_node *n;
+-	struct io_worker *worker;
+-
+-	/*
+-	 * Iterate free_list and see if we can find an idle worker to
+-	 * activate. If a given worker is on the free_list but in the process
+-	 * of exiting, keep trying.
+-	 */
+-	hlist_nulls_for_each_entry_rcu(worker, n, &wqe->free_list, nulls_node) {
+-		if (!io_worker_get(worker))
+-			continue;
+-		if (io_wqe_get_acct(worker) != acct) {
+-			io_worker_release(worker);
+-			continue;
+-		}
+-		if (wake_up_process(worker->task)) {
+-			io_worker_release(worker);
+-			return true;
+-		}
+-		io_worker_release(worker);
+-	}
+-
+-	return false;
+-}
+-
+-/*
+- * We need a worker. If we find a free one, we're good. If not, and we're
+- * below the max number of workers, create one.
+- */
+-static bool io_wqe_create_worker(struct io_wqe *wqe, struct io_wqe_acct *acct)
+-{
+-	/*
+-	 * Most likely an attempt to queue unbounded work on an io_wq that
+-	 * wasn't setup with any unbounded workers.
+-	 */
+-	if (unlikely(!acct->max_workers))
+-		pr_warn_once("io-wq is not configured for unbound workers");
+-
+-	raw_spin_lock(&wqe->lock);
+-	if (acct->nr_workers >= acct->max_workers) {
+-		raw_spin_unlock(&wqe->lock);
+-		return true;
+-	}
+-	acct->nr_workers++;
+-	raw_spin_unlock(&wqe->lock);
+-	atomic_inc(&acct->nr_running);
+-	atomic_inc(&wqe->wq->worker_refs);
+-	return create_io_worker(wqe->wq, wqe, acct->index);
+-}
+-
+-static void io_wqe_inc_running(struct io_worker *worker)
+-{
+-	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
+-
+-	atomic_inc(&acct->nr_running);
+-}
+-
+-static void create_worker_cb(struct callback_head *cb)
+-{
+-	struct io_worker *worker;
+-	struct io_wq *wq;
+-	struct io_wqe *wqe;
+-	struct io_wqe_acct *acct;
+-	bool do_create = false;
+-
+-	worker = container_of(cb, struct io_worker, create_work);
+-	wqe = worker->wqe;
+-	wq = wqe->wq;
+-	acct = &wqe->acct[worker->create_index];
+-	raw_spin_lock(&wqe->lock);
+-	if (acct->nr_workers < acct->max_workers) {
+-		acct->nr_workers++;
+-		do_create = true;
+-	}
+-	raw_spin_unlock(&wqe->lock);
+-	if (do_create) {
+-		create_io_worker(wq, wqe, worker->create_index);
+-	} else {
+-		atomic_dec(&acct->nr_running);
+-		io_worker_ref_put(wq);
+-	}
+-	clear_bit_unlock(0, &worker->create_state);
+-	io_worker_release(worker);
+-}
+-
+-static bool io_queue_worker_create(struct io_worker *worker,
+-				   struct io_wqe_acct *acct,
+-				   task_work_func_t func)
+-{
+-	struct io_wqe *wqe = worker->wqe;
+-	struct io_wq *wq = wqe->wq;
+-
+-	/* raced with exit, just ignore create call */
+-	if (test_bit(IO_WQ_BIT_EXIT, &wq->state))
+-		goto fail;
+-	if (!io_worker_get(worker))
+-		goto fail;
+-	/*
+-	 * create_state manages ownership of create_work/index. We should
+-	 * only need one entry per worker, as the worker going to sleep
+-	 * will trigger the condition, and waking will clear it once it
+-	 * runs the task_work.
+-	 */
+-	if (test_bit(0, &worker->create_state) ||
+-	    test_and_set_bit_lock(0, &worker->create_state))
+-		goto fail_release;
+-
+-	atomic_inc(&wq->worker_refs);
+-	init_task_work(&worker->create_work, func);
+-	worker->create_index = acct->index;
+-	if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL)) {
+-		/*
+-		 * EXIT may have been set after checking it above, check after
+-		 * adding the task_work and remove any creation item if it is
+-		 * now set. wq exit does that too, but we can have added this
+-		 * work item after we canceled in io_wq_exit_workers().
+-		 */
+-		if (test_bit(IO_WQ_BIT_EXIT, &wq->state))
+-			io_wq_cancel_tw_create(wq);
+-		io_worker_ref_put(wq);
+-		return true;
+-	}
+-	io_worker_ref_put(wq);
+-	clear_bit_unlock(0, &worker->create_state);
+-fail_release:
+-	io_worker_release(worker);
+-fail:
+-	atomic_dec(&acct->nr_running);
+-	io_worker_ref_put(wq);
+-	return false;
+-}
+-
+-static void io_wqe_dec_running(struct io_worker *worker)
+-	__must_hold(wqe->lock)
+-{
+-	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
+-	struct io_wqe *wqe = worker->wqe;
+-
+-	if (!(worker->flags & IO_WORKER_F_UP))
+-		return;
+-
+-	if (atomic_dec_and_test(&acct->nr_running) && io_acct_run_queue(acct)) {
+-		atomic_inc(&acct->nr_running);
+-		atomic_inc(&wqe->wq->worker_refs);
+-		raw_spin_unlock(&wqe->lock);
+-		io_queue_worker_create(worker, acct, create_worker_cb);
+-		raw_spin_lock(&wqe->lock);
+-	}
+-}
+-
+-/*
+- * Worker will start processing some work. Move it to the busy list, if
+- * it's currently on the freelist
+- */
+-static void __io_worker_busy(struct io_wqe *wqe, struct io_worker *worker,
+-			     struct io_wq_work *work)
+-	__must_hold(wqe->lock)
+-{
+-	if (worker->flags & IO_WORKER_F_FREE) {
+-		worker->flags &= ~IO_WORKER_F_FREE;
+-		hlist_nulls_del_init_rcu(&worker->nulls_node);
+-	}
+-}
+-
+-/*
+- * No work, worker going to sleep. Move to freelist, and unuse mm if we
+- * have one attached. Dropping the mm may potentially sleep, so we drop
+- * the lock in that case and return success. Since the caller has to
+- * retry the loop in that case (we changed task state), we don't regrab
+- * the lock if we return success.
+- */
+-static void __io_worker_idle(struct io_wqe *wqe, struct io_worker *worker)
+-	__must_hold(wqe->lock)
+-{
+-	if (!(worker->flags & IO_WORKER_F_FREE)) {
+-		worker->flags |= IO_WORKER_F_FREE;
+-		hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list);
+-	}
+-}
+-
+-static inline unsigned int io_get_work_hash(struct io_wq_work *work)
+-{
+-	return work->flags >> IO_WQ_HASH_SHIFT;
+-}
+-
+-static bool io_wait_on_hash(struct io_wqe *wqe, unsigned int hash)
+-{
+-	struct io_wq *wq = wqe->wq;
+-	bool ret = false;
+-
+-	spin_lock_irq(&wq->hash->wait.lock);
+-	if (list_empty(&wqe->wait.entry)) {
+-		__add_wait_queue(&wq->hash->wait, &wqe->wait);
+-		if (!test_bit(hash, &wq->hash->map)) {
+-			__set_current_state(TASK_RUNNING);
+-			list_del_init(&wqe->wait.entry);
+-			ret = true;
+-		}
+-	}
+-	spin_unlock_irq(&wq->hash->wait.lock);
+-	return ret;
+-}
+-
+-static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct,
+-					   struct io_worker *worker)
+-	__must_hold(wqe->lock)
+-{
+-	struct io_wq_work_node *node, *prev;
+-	struct io_wq_work *work, *tail;
+-	unsigned int stall_hash = -1U;
+-	struct io_wqe *wqe = worker->wqe;
+-
+-	wq_list_for_each(node, prev, &acct->work_list) {
+-		unsigned int hash;
+-
+-		work = container_of(node, struct io_wq_work, list);
+-
+-		/* not hashed, can run anytime */
+-		if (!io_wq_is_hashed(work)) {
+-			wq_list_del(&acct->work_list, node, prev);
+-			return work;
+-		}
+-
+-		hash = io_get_work_hash(work);
+-		/* all items with this hash lie in [work, tail] */
+-		tail = wqe->hash_tail[hash];
+-
+-		/* hashed, can run if not already running */
+-		if (!test_and_set_bit(hash, &wqe->wq->hash->map)) {
+-			wqe->hash_tail[hash] = NULL;
+-			wq_list_cut(&acct->work_list, &tail->list, prev);
+-			return work;
+-		}
+-		if (stall_hash == -1U)
+-			stall_hash = hash;
+-		/* fast forward to a next hash, for-each will fix up @prev */
+-		node = &tail->list;
+-	}
+-
+-	if (stall_hash != -1U) {
+-		bool unstalled;
+-
+-		/*
+-		 * Set this before dropping the lock to avoid racing with new
+-		 * work being added and clearing the stalled bit.
+-		 */
+-		set_bit(IO_ACCT_STALLED_BIT, &acct->flags);
+-		raw_spin_unlock(&wqe->lock);
+-		unstalled = io_wait_on_hash(wqe, stall_hash);
+-		raw_spin_lock(&wqe->lock);
+-		if (unstalled) {
+-			clear_bit(IO_ACCT_STALLED_BIT, &acct->flags);
+-			if (wq_has_sleeper(&wqe->wq->hash->wait))
+-				wake_up(&wqe->wq->hash->wait);
+-		}
+-	}
+-
+-	return NULL;
+-}
+-
+-static bool io_flush_signals(void)
+-{
+-	if (unlikely(test_thread_flag(TIF_NOTIFY_SIGNAL))) {
+-		__set_current_state(TASK_RUNNING);
+-		tracehook_notify_signal();
+-		return true;
+-	}
+-	return false;
+-}
+-
+-static void io_assign_current_work(struct io_worker *worker,
+-				   struct io_wq_work *work)
+-{
+-	if (work) {
+-		io_flush_signals();
+-		cond_resched();
+-	}
+-
+-	spin_lock(&worker->lock);
+-	worker->cur_work = work;
+-	spin_unlock(&worker->lock);
+-}
+-
+-static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work);
+-
+-static void io_worker_handle_work(struct io_worker *worker)
+-	__releases(wqe->lock)
+-{
+-	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
+-	struct io_wqe *wqe = worker->wqe;
+-	struct io_wq *wq = wqe->wq;
+-	bool do_kill = test_bit(IO_WQ_BIT_EXIT, &wq->state);
+-
+-	do {
+-		struct io_wq_work *work;
+-get_next:
+-		/*
+-		 * If we got some work, mark us as busy. If we didn't, but
+-		 * the list isn't empty, it means we stalled on hashed work.
+-		 * Mark us stalled so we don't keep looking for work when we
+-		 * can't make progress, any work completion or insertion will
+-		 * clear the stalled flag.
+-		 */
+-		work = io_get_next_work(acct, worker);
+-		if (work)
+-			__io_worker_busy(wqe, worker, work);
+-
+-		raw_spin_unlock(&wqe->lock);
+-		if (!work)
+-			break;
+-		io_assign_current_work(worker, work);
+-		__set_current_state(TASK_RUNNING);
+-
+-		/* handle a whole dependent link */
+-		do {
+-			struct io_wq_work *next_hashed, *linked;
+-			unsigned int hash = io_get_work_hash(work);
+-
+-			next_hashed = wq_next_work(work);
+-
+-			if (unlikely(do_kill) && (work->flags & IO_WQ_WORK_UNBOUND))
+-				work->flags |= IO_WQ_WORK_CANCEL;
+-			wq->do_work(work);
+-			io_assign_current_work(worker, NULL);
+-
+-			linked = wq->free_work(work);
+-			work = next_hashed;
+-			if (!work && linked && !io_wq_is_hashed(linked)) {
+-				work = linked;
+-				linked = NULL;
+-			}
+-			io_assign_current_work(worker, work);
+-			if (linked)
+-				io_wqe_enqueue(wqe, linked);
+-
+-			if (hash != -1U && !next_hashed) {
+-				/* serialize hash clear with wake_up() */
+-				spin_lock_irq(&wq->hash->wait.lock);
+-				clear_bit(hash, &wq->hash->map);
+-				clear_bit(IO_ACCT_STALLED_BIT, &acct->flags);
+-				spin_unlock_irq(&wq->hash->wait.lock);
+-				if (wq_has_sleeper(&wq->hash->wait))
+-					wake_up(&wq->hash->wait);
+-				raw_spin_lock(&wqe->lock);
+-				/* skip unnecessary unlock-lock wqe->lock */
+-				if (!work)
+-					goto get_next;
+-				raw_spin_unlock(&wqe->lock);
+-			}
+-		} while (work);
+-
+-		raw_spin_lock(&wqe->lock);
+-	} while (1);
+-}
+-
+-static int io_wqe_worker(void *data)
+-{
+-	struct io_worker *worker = data;
+-	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
+-	struct io_wqe *wqe = worker->wqe;
+-	struct io_wq *wq = wqe->wq;
+-	bool last_timeout = false;
+-	char buf[TASK_COMM_LEN];
+-
+-	worker->flags |= (IO_WORKER_F_UP | IO_WORKER_F_RUNNING);
+-
+-	snprintf(buf, sizeof(buf), "iou-wrk-%d", wq->task->pid);
+-	set_task_comm(current, buf);
+-
+-	while (!test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
+-		long ret;
+-
+-		set_current_state(TASK_INTERRUPTIBLE);
+-loop:
+-		raw_spin_lock(&wqe->lock);
+-		if (io_acct_run_queue(acct)) {
+-			io_worker_handle_work(worker);
+-			goto loop;
+-		}
+-		/* timed out, exit unless we're the last worker */
+-		if (last_timeout && acct->nr_workers > 1) {
+-			acct->nr_workers--;
+-			raw_spin_unlock(&wqe->lock);
+-			__set_current_state(TASK_RUNNING);
+-			break;
+-		}
+-		last_timeout = false;
+-		__io_worker_idle(wqe, worker);
+-		raw_spin_unlock(&wqe->lock);
+-		if (io_flush_signals())
+-			continue;
+-		ret = schedule_timeout(WORKER_IDLE_TIMEOUT);
+-		if (signal_pending(current)) {
+-			struct ksignal ksig;
+-
+-			if (!get_signal(&ksig))
+-				continue;
+-			break;
+-		}
+-		last_timeout = !ret;
+-	}
+-
+-	if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
+-		raw_spin_lock(&wqe->lock);
+-		io_worker_handle_work(worker);
+-	}
+-
+-	io_worker_exit(worker);
+-	return 0;
+-}
+-
+-/*
+- * Called when a worker is scheduled in. Mark us as currently running.
+- */
+-void io_wq_worker_running(struct task_struct *tsk)
+-{
+-	struct io_worker *worker = tsk->pf_io_worker;
+-
+-	if (!worker)
+-		return;
+-	if (!(worker->flags & IO_WORKER_F_UP))
+-		return;
+-	if (worker->flags & IO_WORKER_F_RUNNING)
+-		return;
+-	worker->flags |= IO_WORKER_F_RUNNING;
+-	io_wqe_inc_running(worker);
+-}
+-
+-/*
+- * Called when worker is going to sleep. If there are no workers currently
+- * running and we have work pending, wake up a free one or create a new one.
+- */
+-void io_wq_worker_sleeping(struct task_struct *tsk)
+-{
+-	struct io_worker *worker = tsk->pf_io_worker;
+-
+-	if (!worker)
+-		return;
+-	if (!(worker->flags & IO_WORKER_F_UP))
+-		return;
+-	if (!(worker->flags & IO_WORKER_F_RUNNING))
+-		return;
+-
+-	worker->flags &= ~IO_WORKER_F_RUNNING;
+-
+-	raw_spin_lock(&worker->wqe->lock);
+-	io_wqe_dec_running(worker);
+-	raw_spin_unlock(&worker->wqe->lock);
+-}
+-
+-static void io_init_new_worker(struct io_wqe *wqe, struct io_worker *worker,
+-			       struct task_struct *tsk)
+-{
+-	tsk->pf_io_worker = worker;
+-	worker->task = tsk;
+-	set_cpus_allowed_ptr(tsk, wqe->cpu_mask);
+-	tsk->flags |= PF_NO_SETAFFINITY;
+-
+-	raw_spin_lock(&wqe->lock);
+-	hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list);
+-	list_add_tail_rcu(&worker->all_list, &wqe->all_list);
+-	worker->flags |= IO_WORKER_F_FREE;
+-	raw_spin_unlock(&wqe->lock);
+-	wake_up_new_task(tsk);
+-}
+-
+-static bool io_wq_work_match_all(struct io_wq_work *work, void *data)
+-{
+-	return true;
+-}
+-
+-static inline bool io_should_retry_thread(long err)
+-{
+-	/*
+-	 * Prevent perpetual task_work retry, if the task (or its group) is
+-	 * exiting.
+-	 */
+-	if (fatal_signal_pending(current))
+-		return false;
+-
+-	switch (err) {
+-	case -EAGAIN:
+-	case -ERESTARTSYS:
+-	case -ERESTARTNOINTR:
+-	case -ERESTARTNOHAND:
+-		return true;
+-	default:
+-		return false;
+-	}
+-}
+-
+-static void create_worker_cont(struct callback_head *cb)
+-{
+-	struct io_worker *worker;
+-	struct task_struct *tsk;
+-	struct io_wqe *wqe;
+-
+-	worker = container_of(cb, struct io_worker, create_work);
+-	clear_bit_unlock(0, &worker->create_state);
+-	wqe = worker->wqe;
+-	tsk = create_io_thread(io_wqe_worker, worker, wqe->node);
+-	if (!IS_ERR(tsk)) {
+-		io_init_new_worker(wqe, worker, tsk);
+-		io_worker_release(worker);
+-		return;
+-	} else if (!io_should_retry_thread(PTR_ERR(tsk))) {
+-		struct io_wqe_acct *acct = io_wqe_get_acct(worker);
+-
+-		atomic_dec(&acct->nr_running);
+-		raw_spin_lock(&wqe->lock);
+-		acct->nr_workers--;
+-		if (!acct->nr_workers) {
+-			struct io_cb_cancel_data match = {
+-				.fn		= io_wq_work_match_all,
+-				.cancel_all	= true,
+-			};
+-
+-			while (io_acct_cancel_pending_work(wqe, acct, &match))
+-				raw_spin_lock(&wqe->lock);
+-		}
+-		raw_spin_unlock(&wqe->lock);
+-		io_worker_ref_put(wqe->wq);
+-		kfree(worker);
+-		return;
+-	}
+-
+-	/* re-create attempts grab a new worker ref, drop the existing one */
+-	io_worker_release(worker);
+-	schedule_work(&worker->work);
+-}
+-
+-static void io_workqueue_create(struct work_struct *work)
+-{
+-	struct io_worker *worker = container_of(work, struct io_worker, work);
+-	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
+-
+-	if (!io_queue_worker_create(worker, acct, create_worker_cont))
+-		kfree(worker);
+-}
+-
+-static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index)
+-{
+-	struct io_wqe_acct *acct = &wqe->acct[index];
+-	struct io_worker *worker;
+-	struct task_struct *tsk;
+-
+-	__set_current_state(TASK_RUNNING);
+-
+-	worker = kzalloc_node(sizeof(*worker), GFP_KERNEL, wqe->node);
+-	if (!worker) {
+-fail:
+-		atomic_dec(&acct->nr_running);
+-		raw_spin_lock(&wqe->lock);
+-		acct->nr_workers--;
+-		raw_spin_unlock(&wqe->lock);
+-		io_worker_ref_put(wq);
+-		return false;
+-	}
+-
+-	refcount_set(&worker->ref, 1);
+-	worker->wqe = wqe;
+-	spin_lock_init(&worker->lock);
+-	init_completion(&worker->ref_done);
+-
+-	if (index == IO_WQ_ACCT_BOUND)
+-		worker->flags |= IO_WORKER_F_BOUND;
+-
+-	tsk = create_io_thread(io_wqe_worker, worker, wqe->node);
+-	if (!IS_ERR(tsk)) {
+-		io_init_new_worker(wqe, worker, tsk);
+-	} else if (!io_should_retry_thread(PTR_ERR(tsk))) {
+-		kfree(worker);
+-		goto fail;
+-	} else {
+-		INIT_WORK(&worker->work, io_workqueue_create);
+-		schedule_work(&worker->work);
+-	}
+-
+-	return true;
+-}
+-
+-/*
+- * Iterate the passed in list and call the specific function for each
+- * worker that isn't exiting
+- */
+-static bool io_wq_for_each_worker(struct io_wqe *wqe,
+-				  bool (*func)(struct io_worker *, void *),
+-				  void *data)
+-{
+-	struct io_worker *worker;
+-	bool ret = false;
+-
+-	list_for_each_entry_rcu(worker, &wqe->all_list, all_list) {
+-		if (io_worker_get(worker)) {
+-			/* no task if node is/was offline */
+-			if (worker->task)
+-				ret = func(worker, data);
+-			io_worker_release(worker);
+-			if (ret)
+-				break;
+-		}
+-	}
+-
+-	return ret;
+-}
+-
+-static bool io_wq_worker_wake(struct io_worker *worker, void *data)
+-{
+-	set_notify_signal(worker->task);
+-	wake_up_process(worker->task);
+-	return false;
+-}
+-
+-static void io_run_cancel(struct io_wq_work *work, struct io_wqe *wqe)
+-{
+-	struct io_wq *wq = wqe->wq;
+-
+-	do {
+-		work->flags |= IO_WQ_WORK_CANCEL;
+-		wq->do_work(work);
+-		work = wq->free_work(work);
+-	} while (work);
+-}
+-
+-static void io_wqe_insert_work(struct io_wqe *wqe, struct io_wq_work *work)
+-{
+-	struct io_wqe_acct *acct = io_work_get_acct(wqe, work);
+-	unsigned int hash;
+-	struct io_wq_work *tail;
+-
+-	if (!io_wq_is_hashed(work)) {
+-append:
+-		wq_list_add_tail(&work->list, &acct->work_list);
+-		return;
+-	}
+-
+-	hash = io_get_work_hash(work);
+-	tail = wqe->hash_tail[hash];
+-	wqe->hash_tail[hash] = work;
+-	if (!tail)
+-		goto append;
+-
+-	wq_list_add_after(&work->list, &tail->list, &acct->work_list);
+-}
+-
+-static bool io_wq_work_match_item(struct io_wq_work *work, void *data)
+-{
+-	return work == data;
+-}
+-
+-static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work)
+-{
+-	struct io_wqe_acct *acct = io_work_get_acct(wqe, work);
+-	unsigned work_flags = work->flags;
+-	bool do_create;
+-
+-	/*
+-	 * If io-wq is exiting for this task, or if the request has explicitly
+-	 * been marked as one that should not get executed, cancel it here.
+-	 */
+-	if (test_bit(IO_WQ_BIT_EXIT, &wqe->wq->state) ||
+-	    (work->flags & IO_WQ_WORK_CANCEL)) {
+-		io_run_cancel(work, wqe);
+-		return;
+-	}
+-
+-	raw_spin_lock(&wqe->lock);
+-	io_wqe_insert_work(wqe, work);
+-	clear_bit(IO_ACCT_STALLED_BIT, &acct->flags);
+-
+-	rcu_read_lock();
+-	do_create = !io_wqe_activate_free_worker(wqe, acct);
+-	rcu_read_unlock();
+-
+-	raw_spin_unlock(&wqe->lock);
+-
+-	if (do_create && ((work_flags & IO_WQ_WORK_CONCURRENT) ||
+-	    !atomic_read(&acct->nr_running))) {
+-		bool did_create;
+-
+-		did_create = io_wqe_create_worker(wqe, acct);
+-		if (likely(did_create))
+-			return;
+-
+-		raw_spin_lock(&wqe->lock);
+-		/* fatal condition, failed to create the first worker */
+-		if (!acct->nr_workers) {
+-			struct io_cb_cancel_data match = {
+-				.fn		= io_wq_work_match_item,
+-				.data		= work,
+-				.cancel_all	= false,
+-			};
+-
+-			if (io_acct_cancel_pending_work(wqe, acct, &match))
+-				raw_spin_lock(&wqe->lock);
+-		}
+-		raw_spin_unlock(&wqe->lock);
+-	}
+-}
+-
+-void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work)
+-{
+-	struct io_wqe *wqe = wq->wqes[numa_node_id()];
+-
+-	io_wqe_enqueue(wqe, work);
+-}
+-
+-/*
+- * Work items that hash to the same value will not be done in parallel.
+- * Used to limit concurrent writes, generally hashed by inode.
+- */
+-void io_wq_hash_work(struct io_wq_work *work, void *val)
+-{
+-	unsigned int bit;
+-
+-	bit = hash_ptr(val, IO_WQ_HASH_ORDER);
+-	work->flags |= (IO_WQ_WORK_HASHED | (bit << IO_WQ_HASH_SHIFT));
+-}
+-
+-static bool io_wq_worker_cancel(struct io_worker *worker, void *data)
+-{
+-	struct io_cb_cancel_data *match = data;
+-
+-	/*
+-	 * Hold the lock to avoid ->cur_work going out of scope, caller
+-	 * may dereference the passed in work.
+-	 */
+-	spin_lock(&worker->lock);
+-	if (worker->cur_work &&
+-	    match->fn(worker->cur_work, match->data)) {
+-		set_notify_signal(worker->task);
+-		match->nr_running++;
+-	}
+-	spin_unlock(&worker->lock);
+-
+-	return match->nr_running && !match->cancel_all;
+-}
+-
+-static inline void io_wqe_remove_pending(struct io_wqe *wqe,
+-					 struct io_wq_work *work,
+-					 struct io_wq_work_node *prev)
+-{
+-	struct io_wqe_acct *acct = io_work_get_acct(wqe, work);
+-	unsigned int hash = io_get_work_hash(work);
+-	struct io_wq_work *prev_work = NULL;
+-
+-	if (io_wq_is_hashed(work) && work == wqe->hash_tail[hash]) {
+-		if (prev)
+-			prev_work = container_of(prev, struct io_wq_work, list);
+-		if (prev_work && io_get_work_hash(prev_work) == hash)
+-			wqe->hash_tail[hash] = prev_work;
+-		else
+-			wqe->hash_tail[hash] = NULL;
+-	}
+-	wq_list_del(&acct->work_list, &work->list, prev);
+-}
+-
+-static bool io_acct_cancel_pending_work(struct io_wqe *wqe,
+-					struct io_wqe_acct *acct,
+-					struct io_cb_cancel_data *match)
+-	__releases(wqe->lock)
+-{
+-	struct io_wq_work_node *node, *prev;
+-	struct io_wq_work *work;
+-
+-	wq_list_for_each(node, prev, &acct->work_list) {
+-		work = container_of(node, struct io_wq_work, list);
+-		if (!match->fn(work, match->data))
+-			continue;
+-		io_wqe_remove_pending(wqe, work, prev);
+-		raw_spin_unlock(&wqe->lock);
+-		io_run_cancel(work, wqe);
+-		match->nr_pending++;
+-		/* not safe to continue after unlock */
+-		return true;
+-	}
+-
+-	return false;
+-}
+-
+-static void io_wqe_cancel_pending_work(struct io_wqe *wqe,
+-				       struct io_cb_cancel_data *match)
+-{
+-	int i;
+-retry:
+-	raw_spin_lock(&wqe->lock);
+-	for (i = 0; i < IO_WQ_ACCT_NR; i++) {
+-		struct io_wqe_acct *acct = io_get_acct(wqe, i == 0);
+-
+-		if (io_acct_cancel_pending_work(wqe, acct, match)) {
+-			if (match->cancel_all)
+-				goto retry;
+-			return;
+-		}
+-	}
+-	raw_spin_unlock(&wqe->lock);
+-}
+-
+-static void io_wqe_cancel_running_work(struct io_wqe *wqe,
+-				       struct io_cb_cancel_data *match)
+-{
+-	rcu_read_lock();
+-	io_wq_for_each_worker(wqe, io_wq_worker_cancel, match);
+-	rcu_read_unlock();
+-}
+-
+-enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
+-				  void *data, bool cancel_all)
+-{
+-	struct io_cb_cancel_data match = {
+-		.fn		= cancel,
+-		.data		= data,
+-		.cancel_all	= cancel_all,
+-	};
+-	int node;
+-
+-	/*
+-	 * First check pending list, if we're lucky we can just remove it
+-	 * from there. CANCEL_OK means that the work is returned as-new,
+-	 * no completion will be posted for it.
+-	 */
+-	for_each_node(node) {
+-		struct io_wqe *wqe = wq->wqes[node];
+-
+-		io_wqe_cancel_pending_work(wqe, &match);
+-		if (match.nr_pending && !match.cancel_all)
+-			return IO_WQ_CANCEL_OK;
+-	}
+-
+-	/*
+-	 * Now check if a free (going busy) or busy worker has the work
+-	 * currently running. If we find it there, we'll return CANCEL_RUNNING
+-	 * as an indication that we attempt to signal cancellation. The
+-	 * completion will run normally in this case.
+-	 */
+-	for_each_node(node) {
+-		struct io_wqe *wqe = wq->wqes[node];
+-
+-		io_wqe_cancel_running_work(wqe, &match);
+-		if (match.nr_running && !match.cancel_all)
+-			return IO_WQ_CANCEL_RUNNING;
+-	}
+-
+-	if (match.nr_running)
+-		return IO_WQ_CANCEL_RUNNING;
+-	if (match.nr_pending)
+-		return IO_WQ_CANCEL_OK;
+-	return IO_WQ_CANCEL_NOTFOUND;
+-}
+-
+-static int io_wqe_hash_wake(struct wait_queue_entry *wait, unsigned mode,
+-			    int sync, void *key)
+-{
+-	struct io_wqe *wqe = container_of(wait, struct io_wqe, wait);
+-	int i;
+-
+-	list_del_init(&wait->entry);
+-
+-	rcu_read_lock();
+-	for (i = 0; i < IO_WQ_ACCT_NR; i++) {
+-		struct io_wqe_acct *acct = &wqe->acct[i];
+-
+-		if (test_and_clear_bit(IO_ACCT_STALLED_BIT, &acct->flags))
+-			io_wqe_activate_free_worker(wqe, acct);
+-	}
+-	rcu_read_unlock();
+-	return 1;
+-}
+-
+-struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data)
+-{
+-	int ret, node, i;
+-	struct io_wq *wq;
+-
+-	if (WARN_ON_ONCE(!data->free_work || !data->do_work))
+-		return ERR_PTR(-EINVAL);
+-	if (WARN_ON_ONCE(!bounded))
+-		return ERR_PTR(-EINVAL);
+-
+-	wq = kzalloc(struct_size(wq, wqes, nr_node_ids), GFP_KERNEL);
+-	if (!wq)
+-		return ERR_PTR(-ENOMEM);
+-	ret = cpuhp_state_add_instance_nocalls(io_wq_online, &wq->cpuhp_node);
+-	if (ret)
+-		goto err_wq;
+-
+-	refcount_inc(&data->hash->refs);
+-	wq->hash = data->hash;
+-	wq->free_work = data->free_work;
+-	wq->do_work = data->do_work;
+-
+-	ret = -ENOMEM;
+-	for_each_node(node) {
+-		struct io_wqe *wqe;
+-		int alloc_node = node;
+-
+-		if (!node_online(alloc_node))
+-			alloc_node = NUMA_NO_NODE;
+-		wqe = kzalloc_node(sizeof(struct io_wqe), GFP_KERNEL, alloc_node);
+-		if (!wqe)
+-			goto err;
+-		wq->wqes[node] = wqe;
+-		if (!alloc_cpumask_var(&wqe->cpu_mask, GFP_KERNEL))
+-			goto err;
+-		cpumask_copy(wqe->cpu_mask, cpumask_of_node(node));
+-		wqe->node = alloc_node;
+-		wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded;
+-		wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers =
+-					task_rlimit(current, RLIMIT_NPROC);
+-		INIT_LIST_HEAD(&wqe->wait.entry);
+-		wqe->wait.func = io_wqe_hash_wake;
+-		for (i = 0; i < IO_WQ_ACCT_NR; i++) {
+-			struct io_wqe_acct *acct = &wqe->acct[i];
+-
+-			acct->index = i;
+-			atomic_set(&acct->nr_running, 0);
+-			INIT_WQ_LIST(&acct->work_list);
+-		}
+-		wqe->wq = wq;
+-		raw_spin_lock_init(&wqe->lock);
+-		INIT_HLIST_NULLS_HEAD(&wqe->free_list, 0);
+-		INIT_LIST_HEAD(&wqe->all_list);
+-	}
+-
+-	wq->task = get_task_struct(data->task);
+-	atomic_set(&wq->worker_refs, 1);
+-	init_completion(&wq->worker_done);
+-	return wq;
+-err:
+-	io_wq_put_hash(data->hash);
+-	cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node);
+-	for_each_node(node) {
+-		if (!wq->wqes[node])
+-			continue;
+-		free_cpumask_var(wq->wqes[node]->cpu_mask);
+-		kfree(wq->wqes[node]);
+-	}
+-err_wq:
+-	kfree(wq);
+-	return ERR_PTR(ret);
+-}
+-
+-static bool io_task_work_match(struct callback_head *cb, void *data)
+-{
+-	struct io_worker *worker;
+-
+-	if (cb->func != create_worker_cb && cb->func != create_worker_cont)
+-		return false;
+-	worker = container_of(cb, struct io_worker, create_work);
+-	return worker->wqe->wq == data;
+-}
+-
+-void io_wq_exit_start(struct io_wq *wq)
+-{
+-	set_bit(IO_WQ_BIT_EXIT, &wq->state);
+-}
+-
+-static void io_wq_cancel_tw_create(struct io_wq *wq)
+-{
+-	struct callback_head *cb;
+-
+-	while ((cb = task_work_cancel_match(wq->task, io_task_work_match, wq)) != NULL) {
+-		struct io_worker *worker;
+-
+-		worker = container_of(cb, struct io_worker, create_work);
+-		io_worker_cancel_cb(worker);
+-	}
+-}
+-
+-static void io_wq_exit_workers(struct io_wq *wq)
+-{
+-	int node;
+-
+-	if (!wq->task)
+-		return;
+-
+-	io_wq_cancel_tw_create(wq);
+-
+-	rcu_read_lock();
+-	for_each_node(node) {
+-		struct io_wqe *wqe = wq->wqes[node];
+-
+-		io_wq_for_each_worker(wqe, io_wq_worker_wake, NULL);
+-	}
+-	rcu_read_unlock();
+-	io_worker_ref_put(wq);
+-	wait_for_completion(&wq->worker_done);
+-
+-	for_each_node(node) {
+-		spin_lock_irq(&wq->hash->wait.lock);
+-		list_del_init(&wq->wqes[node]->wait.entry);
+-		spin_unlock_irq(&wq->hash->wait.lock);
+-	}
+-	put_task_struct(wq->task);
+-	wq->task = NULL;
+-}
+-
+-static void io_wq_destroy(struct io_wq *wq)
+-{
+-	int node;
+-
+-	cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node);
+-
+-	for_each_node(node) {
+-		struct io_wqe *wqe = wq->wqes[node];
+-		struct io_cb_cancel_data match = {
+-			.fn		= io_wq_work_match_all,
+-			.cancel_all	= true,
+-		};
+-		io_wqe_cancel_pending_work(wqe, &match);
+-		free_cpumask_var(wqe->cpu_mask);
+-		kfree(wqe);
+-	}
+-	io_wq_put_hash(wq->hash);
+-	kfree(wq);
+-}
+-
+-void io_wq_put_and_exit(struct io_wq *wq)
+-{
+-	WARN_ON_ONCE(!test_bit(IO_WQ_BIT_EXIT, &wq->state));
+-
+-	io_wq_exit_workers(wq);
+-	io_wq_destroy(wq);
+-}
+-
+-struct online_data {
+-	unsigned int cpu;
+-	bool online;
+-};
+-
+-static bool io_wq_worker_affinity(struct io_worker *worker, void *data)
+-{
+-	struct online_data *od = data;
+-
+-	if (od->online)
+-		cpumask_set_cpu(od->cpu, worker->wqe->cpu_mask);
+-	else
+-		cpumask_clear_cpu(od->cpu, worker->wqe->cpu_mask);
+-	return false;
+-}
+-
+-static int __io_wq_cpu_online(struct io_wq *wq, unsigned int cpu, bool online)
+-{
+-	struct online_data od = {
+-		.cpu = cpu,
+-		.online = online
+-	};
+-	int i;
+-
+-	rcu_read_lock();
+-	for_each_node(i)
+-		io_wq_for_each_worker(wq->wqes[i], io_wq_worker_affinity, &od);
+-	rcu_read_unlock();
+-	return 0;
+-}
+-
+-static int io_wq_cpu_online(unsigned int cpu, struct hlist_node *node)
+-{
+-	struct io_wq *wq = hlist_entry_safe(node, struct io_wq, cpuhp_node);
+-
+-	return __io_wq_cpu_online(wq, cpu, true);
+-}
+-
+-static int io_wq_cpu_offline(unsigned int cpu, struct hlist_node *node)
+-{
+-	struct io_wq *wq = hlist_entry_safe(node, struct io_wq, cpuhp_node);
+-
+-	return __io_wq_cpu_online(wq, cpu, false);
+-}
+-
+-int io_wq_cpu_affinity(struct io_wq *wq, cpumask_var_t mask)
+-{
+-	int i;
+-
+-	rcu_read_lock();
+-	for_each_node(i) {
+-		struct io_wqe *wqe = wq->wqes[i];
+-
+-		if (mask)
+-			cpumask_copy(wqe->cpu_mask, mask);
+-		else
+-			cpumask_copy(wqe->cpu_mask, cpumask_of_node(i));
+-	}
+-	rcu_read_unlock();
+-	return 0;
+-}
+-
+-/*
+- * Set max number of unbounded workers, returns old value. If new_count is 0,
+- * then just return the old value.
+- */
+-int io_wq_max_workers(struct io_wq *wq, int *new_count)
+-{
+-	int prev[IO_WQ_ACCT_NR];
+-	bool first_node = true;
+-	int i, node;
+-
+-	BUILD_BUG_ON((int) IO_WQ_ACCT_BOUND   != (int) IO_WQ_BOUND);
+-	BUILD_BUG_ON((int) IO_WQ_ACCT_UNBOUND != (int) IO_WQ_UNBOUND);
+-	BUILD_BUG_ON((int) IO_WQ_ACCT_NR      != 2);
+-
+-	for (i = 0; i < 2; i++) {
+-		if (new_count[i] > task_rlimit(current, RLIMIT_NPROC))
+-			new_count[i] = task_rlimit(current, RLIMIT_NPROC);
+-	}
+-
+-	for (i = 0; i < IO_WQ_ACCT_NR; i++)
+-		prev[i] = 0;
+-
+-	rcu_read_lock();
+-	for_each_node(node) {
+-		struct io_wqe *wqe = wq->wqes[node];
+-		struct io_wqe_acct *acct;
+-
+-		raw_spin_lock(&wqe->lock);
+-		for (i = 0; i < IO_WQ_ACCT_NR; i++) {
+-			acct = &wqe->acct[i];
+-			if (first_node)
+-				prev[i] = max_t(int, acct->max_workers, prev[i]);
+-			if (new_count[i])
+-				acct->max_workers = new_count[i];
+-		}
+-		raw_spin_unlock(&wqe->lock);
+-		first_node = false;
+-	}
+-	rcu_read_unlock();
+-
+-	for (i = 0; i < IO_WQ_ACCT_NR; i++)
+-		new_count[i] = prev[i];
+-
+-	return 0;
+-}
+-
+-static __init int io_wq_init(void)
+-{
+-	int ret;
+-
+-	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "io-wq/online",
+-					io_wq_cpu_online, io_wq_cpu_offline);
+-	if (ret < 0)
+-		return ret;
+-	io_wq_online = ret;
+-	return 0;
+-}
+-subsys_initcall(io_wq_init);
+diff --git a/fs/io-wq.h b/fs/io-wq.h
+deleted file mode 100644
+index bf5c4c5337605..0000000000000
+--- a/fs/io-wq.h
++++ /dev/null
+@@ -1,160 +0,0 @@
+-#ifndef INTERNAL_IO_WQ_H
+-#define INTERNAL_IO_WQ_H
+-
+-#include <linux/refcount.h>
+-
+-struct io_wq;
+-
+-enum {
+-	IO_WQ_WORK_CANCEL	= 1,
+-	IO_WQ_WORK_HASHED	= 2,
+-	IO_WQ_WORK_UNBOUND	= 4,
+-	IO_WQ_WORK_CONCURRENT	= 16,
+-
+-	IO_WQ_HASH_SHIFT	= 24,	/* upper 8 bits are used for hash key */
+-};
+-
+-enum io_wq_cancel {
+-	IO_WQ_CANCEL_OK,	/* cancelled before started */
+-	IO_WQ_CANCEL_RUNNING,	/* found, running, and attempted cancelled */
+-	IO_WQ_CANCEL_NOTFOUND,	/* work not found */
+-};
+-
+-struct io_wq_work_node {
+-	struct io_wq_work_node *next;
+-};
+-
+-struct io_wq_work_list {
+-	struct io_wq_work_node *first;
+-	struct io_wq_work_node *last;
+-};
+-
+-static inline void wq_list_add_after(struct io_wq_work_node *node,
+-				     struct io_wq_work_node *pos,
+-				     struct io_wq_work_list *list)
+-{
+-	struct io_wq_work_node *next = pos->next;
+-
+-	pos->next = node;
+-	node->next = next;
+-	if (!next)
+-		list->last = node;
+-}
+-
+-static inline void wq_list_add_tail(struct io_wq_work_node *node,
+-				    struct io_wq_work_list *list)
+-{
+-	node->next = NULL;
+-	if (!list->first) {
+-		list->last = node;
+-		WRITE_ONCE(list->first, node);
+-	} else {
+-		list->last->next = node;
+-		list->last = node;
+-	}
+-}
+-
+-static inline void wq_list_cut(struct io_wq_work_list *list,
+-			       struct io_wq_work_node *last,
+-			       struct io_wq_work_node *prev)
+-{
+-	/* first in the list, if prev==NULL */
+-	if (!prev)
+-		WRITE_ONCE(list->first, last->next);
+-	else
+-		prev->next = last->next;
+-
+-	if (last == list->last)
+-		list->last = prev;
+-	last->next = NULL;
+-}
+-
+-static inline void wq_list_del(struct io_wq_work_list *list,
+-			       struct io_wq_work_node *node,
+-			       struct io_wq_work_node *prev)
+-{
+-	wq_list_cut(list, node, prev);
+-}
+-
+-#define wq_list_for_each(pos, prv, head)			\
+-	for (pos = (head)->first, prv = NULL; pos; prv = pos, pos = (pos)->next)
+-
+-#define wq_list_empty(list)	(READ_ONCE((list)->first) == NULL)
+-#define INIT_WQ_LIST(list)	do {				\
+-	(list)->first = NULL;					\
+-	(list)->last = NULL;					\
+-} while (0)
+-
+-struct io_wq_work {
+-	struct io_wq_work_node list;
+-	unsigned flags;
+-};
+-
+-static inline struct io_wq_work *wq_next_work(struct io_wq_work *work)
+-{
+-	if (!work->list.next)
+-		return NULL;
+-
+-	return container_of(work->list.next, struct io_wq_work, list);
+-}
+-
+-typedef struct io_wq_work *(free_work_fn)(struct io_wq_work *);
+-typedef void (io_wq_work_fn)(struct io_wq_work *);
+-
+-struct io_wq_hash {
+-	refcount_t refs;
+-	unsigned long map;
+-	struct wait_queue_head wait;
+-};
+-
+-static inline void io_wq_put_hash(struct io_wq_hash *hash)
+-{
+-	if (refcount_dec_and_test(&hash->refs))
+-		kfree(hash);
+-}
+-
+-struct io_wq_data {
+-	struct io_wq_hash *hash;
+-	struct task_struct *task;
+-	io_wq_work_fn *do_work;
+-	free_work_fn *free_work;
+-};
+-
+-struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data);
+-void io_wq_exit_start(struct io_wq *wq);
+-void io_wq_put_and_exit(struct io_wq *wq);
+-
+-void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work);
+-void io_wq_hash_work(struct io_wq_work *work, void *val);
+-
+-int io_wq_cpu_affinity(struct io_wq *wq, cpumask_var_t mask);
+-int io_wq_max_workers(struct io_wq *wq, int *new_count);
+-
+-static inline bool io_wq_is_hashed(struct io_wq_work *work)
+-{
+-	return work->flags & IO_WQ_WORK_HASHED;
+-}
+-
+-typedef bool (work_cancel_fn)(struct io_wq_work *, void *);
+-
+-enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
+-					void *data, bool cancel_all);
+-
+-#if defined(CONFIG_IO_WQ)
+-extern void io_wq_worker_sleeping(struct task_struct *);
+-extern void io_wq_worker_running(struct task_struct *);
+-#else
+-static inline void io_wq_worker_sleeping(struct task_struct *tsk)
+-{
+-}
+-static inline void io_wq_worker_running(struct task_struct *tsk)
+-{
+-}
+-#endif
+-
+-static inline bool io_wq_current_is_worker(void)
+-{
+-	return in_task() && (current->flags & PF_IO_WORKER) &&
+-		current->pf_io_worker;
+-}
+-#endif
+diff --git a/fs/io_uring.c b/fs/io_uring.c
+deleted file mode 100644
+index c2fdde6fdda38..0000000000000
+--- a/fs/io_uring.c
++++ /dev/null
+@@ -1,11110 +0,0 @@
+-// SPDX-License-Identifier: GPL-2.0
+-/*
+- * Shared application/kernel submission and completion ring pairs, for
+- * supporting fast/efficient IO.
+- *
+- * A note on the read/write ordering memory barriers that are matched between
+- * the application and kernel side.
+- *
+- * After the application reads the CQ ring tail, it must use an
+- * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
+- * before writing the tail (using smp_load_acquire to read the tail will
+- * do). It also needs a smp_mb() before updating CQ head (ordering the
+- * entry load(s) with the head store), pairing with an implicit barrier
+- * through a control-dependency in io_get_cqe (smp_store_release to
+- * store head will do). Failure to do so could lead to reading invalid
+- * CQ entries.
+- *
+- * Likewise, the application must use an appropriate smp_wmb() before
+- * writing the SQ tail (ordering SQ entry stores with the tail store),
+- * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
+- * to store the tail will do). And it needs a barrier ordering the SQ
+- * head load before writing new SQ entries (smp_load_acquire to read
+- * head will do).
+- *
+- * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
+- * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
+- * updating the SQ tail; a full memory barrier smp_mb() is needed
+- * between.
+- *
+- * Also see the examples in the liburing library:
+- *
+- *	git://git.kernel.dk/liburing
+- *
+- * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
+- * from data shared between the kernel and application. This is done both
+- * for ordering purposes, but also to ensure that once a value is loaded from
+- * data that the application could potentially modify, it remains stable.
+- *
+- * Copyright (C) 2018-2019 Jens Axboe
+- * Copyright (c) 2018-2019 Christoph Hellwig
+- */
+-#include <linux/kernel.h>
+-#include <linux/init.h>
+-#include <linux/errno.h>
+-#include <linux/syscalls.h>
+-#include <linux/compat.h>
+-#include <net/compat.h>
+-#include <linux/refcount.h>
+-#include <linux/uio.h>
+-#include <linux/bits.h>
+-
+-#include <linux/sched/signal.h>
+-#include <linux/fs.h>
+-#include <linux/file.h>
+-#include <linux/fdtable.h>
+-#include <linux/mm.h>
+-#include <linux/mman.h>
+-#include <linux/percpu.h>
+-#include <linux/slab.h>
+-#include <linux/blkdev.h>
+-#include <linux/bvec.h>
+-#include <linux/net.h>
+-#include <net/sock.h>
+-#include <net/af_unix.h>
+-#include <net/scm.h>
+-#include <linux/anon_inodes.h>
+-#include <linux/sched/mm.h>
+-#include <linux/uaccess.h>
+-#include <linux/nospec.h>
+-#include <linux/sizes.h>
+-#include <linux/hugetlb.h>
+-#include <linux/highmem.h>
+-#include <linux/namei.h>
+-#include <linux/fsnotify.h>
+-#include <linux/fadvise.h>
+-#include <linux/eventpoll.h>
+-#include <linux/splice.h>
+-#include <linux/task_work.h>
+-#include <linux/pagemap.h>
+-#include <linux/io_uring.h>
+-#include <linux/tracehook.h>
+-
+-#define CREATE_TRACE_POINTS
+-#include <trace/events/io_uring.h>
+-
+-#include <uapi/linux/io_uring.h>
+-
+-#include "internal.h"
+-#include "io-wq.h"
+-
+-#define IORING_MAX_ENTRIES	32768
+-#define IORING_MAX_CQ_ENTRIES	(2 * IORING_MAX_ENTRIES)
+-#define IORING_SQPOLL_CAP_ENTRIES_VALUE 8
+-
+-/* only define max */
+-#define IORING_MAX_FIXED_FILES	(1U << 15)
+-#define IORING_MAX_RESTRICTIONS	(IORING_RESTRICTION_LAST + \
+-				 IORING_REGISTER_LAST + IORING_OP_LAST)
+-
+-#define IO_RSRC_TAG_TABLE_SHIFT	(PAGE_SHIFT - 3)
+-#define IO_RSRC_TAG_TABLE_MAX	(1U << IO_RSRC_TAG_TABLE_SHIFT)
+-#define IO_RSRC_TAG_TABLE_MASK	(IO_RSRC_TAG_TABLE_MAX - 1)
+-
+-#define IORING_MAX_REG_BUFFERS	(1U << 14)
+-
+-#define SQE_VALID_FLAGS	(IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK|	\
+-				IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
+-				IOSQE_BUFFER_SELECT)
+-#define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
+-				REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS)
+-
+-#define IO_TCTX_REFS_CACHE_NR	(1U << 10)
+-
+-struct io_uring {
+-	u32 head ____cacheline_aligned_in_smp;
+-	u32 tail ____cacheline_aligned_in_smp;
+-};
+-
+-/*
+- * This data is shared with the application through the mmap at offsets
+- * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
+- *
+- * The offsets to the member fields are published through struct
+- * io_sqring_offsets when calling io_uring_setup.
+- */
+-struct io_rings {
+-	/*
+-	 * Head and tail offsets into the ring; the offsets need to be
+-	 * masked to get valid indices.
+-	 *
+-	 * The kernel controls head of the sq ring and the tail of the cq ring,
+-	 * and the application controls tail of the sq ring and the head of the
+-	 * cq ring.
+-	 */
+-	struct io_uring		sq, cq;
+-	/*
+-	 * Bitmasks to apply to head and tail offsets (constant, equals
+-	 * ring_entries - 1)
+-	 */
+-	u32			sq_ring_mask, cq_ring_mask;
+-	/* Ring sizes (constant, power of 2) */
+-	u32			sq_ring_entries, cq_ring_entries;
+-	/*
+-	 * Number of invalid entries dropped by the kernel due to
+-	 * invalid index stored in array
+-	 *
+-	 * Written by the kernel, shouldn't be modified by the
+-	 * application (i.e. get number of "new events" by comparing to
+-	 * cached value).
+-	 *
+-	 * After a new SQ head value was read by the application this
+-	 * counter includes all submissions that were dropped reaching
+-	 * the new SQ head (and possibly more).
+-	 */
+-	u32			sq_dropped;
+-	/*
+-	 * Runtime SQ flags
+-	 *
+-	 * Written by the kernel, shouldn't be modified by the
+-	 * application.
+-	 *
+-	 * The application needs a full memory barrier before checking
+-	 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
+-	 */
+-	u32			sq_flags;
+-	/*
+-	 * Runtime CQ flags
+-	 *
+-	 * Written by the application, shouldn't be modified by the
+-	 * kernel.
+-	 */
+-	u32			cq_flags;
+-	/*
+-	 * Number of completion events lost because the queue was full;
+-	 * this should be avoided by the application by making sure
+-	 * there are not more requests pending than there is space in
+-	 * the completion queue.
+-	 *
+-	 * Written by the kernel, shouldn't be modified by the
+-	 * application (i.e. get number of "new events" by comparing to
+-	 * cached value).
+-	 *
+-	 * As completion events come in out of order this counter is not
+-	 * ordered with any other data.
+-	 */
+-	u32			cq_overflow;
+-	/*
+-	 * Ring buffer of completion events.
+-	 *
+-	 * The kernel writes completion events fresh every time they are
+-	 * produced, so the application is allowed to modify pending
+-	 * entries.
+-	 */
+-	struct io_uring_cqe	cqes[] ____cacheline_aligned_in_smp;
+-};
+-
+-enum io_uring_cmd_flags {
+-	IO_URING_F_NONBLOCK		= 1,
+-	IO_URING_F_COMPLETE_DEFER	= 2,
+-};
+-
+-struct io_mapped_ubuf {
+-	u64		ubuf;
+-	u64		ubuf_end;
+-	unsigned int	nr_bvecs;
+-	unsigned long	acct_pages;
+-	struct bio_vec	bvec[];
+-};
+-
+-struct io_ring_ctx;
+-
+-struct io_overflow_cqe {
+-	struct io_uring_cqe cqe;
+-	struct list_head list;
+-};
+-
+-struct io_fixed_file {
+-	/* file * with additional FFS_* flags */
+-	unsigned long file_ptr;
+-};
+-
+-struct io_rsrc_put {
+-	struct list_head list;
+-	u64 tag;
+-	union {
+-		void *rsrc;
+-		struct file *file;
+-		struct io_mapped_ubuf *buf;
+-	};
+-};
+-
+-struct io_file_table {
+-	struct io_fixed_file *files;
+-};
+-
+-struct io_rsrc_node {
+-	struct percpu_ref		refs;
+-	struct list_head		node;
+-	struct list_head		rsrc_list;
+-	struct io_rsrc_data		*rsrc_data;
+-	struct llist_node		llist;
+-	bool				done;
+-};
+-
+-typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
+-
+-struct io_rsrc_data {
+-	struct io_ring_ctx		*ctx;
+-
+-	u64				**tags;
+-	unsigned int			nr;
+-	rsrc_put_fn			*do_put;
+-	atomic_t			refs;
+-	struct completion		done;
+-	bool				quiesce;
+-};
+-
+-struct io_buffer {
+-	struct list_head list;
+-	__u64 addr;
+-	__u32 len;
+-	__u16 bid;
+-};
+-
+-struct io_restriction {
+-	DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
+-	DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
+-	u8 sqe_flags_allowed;
+-	u8 sqe_flags_required;
+-	bool registered;
+-};
+-
+-enum {
+-	IO_SQ_THREAD_SHOULD_STOP = 0,
+-	IO_SQ_THREAD_SHOULD_PARK,
+-};
+-
+-struct io_sq_data {
+-	refcount_t		refs;
+-	atomic_t		park_pending;
+-	struct mutex		lock;
+-
+-	/* ctx's that are using this sqd */
+-	struct list_head	ctx_list;
+-
+-	struct task_struct	*thread;
+-	struct wait_queue_head	wait;
+-
+-	unsigned		sq_thread_idle;
+-	int			sq_cpu;
+-	pid_t			task_pid;
+-	pid_t			task_tgid;
+-
+-	unsigned long		state;
+-	struct completion	exited;
+-};
+-
+-#define IO_COMPL_BATCH			32
+-#define IO_REQ_CACHE_SIZE		32
+-#define IO_REQ_ALLOC_BATCH		8
+-
+-struct io_submit_link {
+-	struct io_kiocb		*head;
+-	struct io_kiocb		*last;
+-};
+-
+-struct io_submit_state {
+-	struct blk_plug		plug;
+-	struct io_submit_link	link;
+-
+-	/*
+-	 * io_kiocb alloc cache
+-	 */
+-	void			*reqs[IO_REQ_CACHE_SIZE];
+-	unsigned int		free_reqs;
+-
+-	bool			plug_started;
+-
+-	/*
+-	 * Batch completion logic
+-	 */
+-	struct io_kiocb		*compl_reqs[IO_COMPL_BATCH];
+-	unsigned int		compl_nr;
+-	/* inline/task_work completion list, under ->uring_lock */
+-	struct list_head	free_list;
+-
+-	unsigned int		ios_left;
+-};
+-
+-struct io_ring_ctx {
+-	/* const or read-mostly hot data */
+-	struct {
+-		struct percpu_ref	refs;
+-
+-		struct io_rings		*rings;
+-		unsigned int		flags;
+-		unsigned int		compat: 1;
+-		unsigned int		drain_next: 1;
+-		unsigned int		eventfd_async: 1;
+-		unsigned int		restricted: 1;
+-		unsigned int		off_timeout_used: 1;
+-		unsigned int		drain_active: 1;
+-	} ____cacheline_aligned_in_smp;
+-
+-	/* submission data */
+-	struct {
+-		struct mutex		uring_lock;
+-
+-		/*
+-		 * Ring buffer of indices into array of io_uring_sqe, which is
+-		 * mmapped by the application using the IORING_OFF_SQES offset.
+-		 *
+-		 * This indirection could e.g. be used to assign fixed
+-		 * io_uring_sqe entries to operations and only submit them to
+-		 * the queue when needed.
+-		 *
+-		 * The kernel modifies neither the indices array nor the entries
+-		 * array.
+-		 */
+-		u32			*sq_array;
+-		struct io_uring_sqe	*sq_sqes;
+-		unsigned		cached_sq_head;
+-		unsigned		sq_entries;
+-		struct list_head	defer_list;
+-
+-		/*
+-		 * Fixed resources fast path, should be accessed only under
+-		 * uring_lock, and updated through io_uring_register(2)
+-		 */
+-		struct io_rsrc_node	*rsrc_node;
+-		struct io_file_table	file_table;
+-		unsigned		nr_user_files;
+-		unsigned		nr_user_bufs;
+-		struct io_mapped_ubuf	**user_bufs;
+-
+-		struct io_submit_state	submit_state;
+-		struct list_head	timeout_list;
+-		struct list_head	ltimeout_list;
+-		struct list_head	cq_overflow_list;
+-		struct xarray		io_buffers;
+-		struct xarray		personalities;
+-		u32			pers_next;
+-		unsigned		sq_thread_idle;
+-	} ____cacheline_aligned_in_smp;
+-
+-	/* IRQ completion list, under ->completion_lock */
+-	struct list_head	locked_free_list;
+-	unsigned int		locked_free_nr;
+-
+-	const struct cred	*sq_creds;	/* cred used for __io_sq_thread() */
+-	struct io_sq_data	*sq_data;	/* if using sq thread polling */
+-
+-	struct wait_queue_head	sqo_sq_wait;
+-	struct list_head	sqd_list;
+-
+-	unsigned long		check_cq_overflow;
+-
+-	struct {
+-		unsigned		cached_cq_tail;
+-		unsigned		cq_entries;
+-		struct eventfd_ctx	*cq_ev_fd;
+-		struct wait_queue_head	poll_wait;
+-		struct wait_queue_head	cq_wait;
+-		unsigned		cq_extra;
+-		atomic_t		cq_timeouts;
+-		unsigned		cq_last_tm_flush;
+-	} ____cacheline_aligned_in_smp;
+-
+-	struct {
+-		spinlock_t		completion_lock;
+-
+-		spinlock_t		timeout_lock;
+-
+-		/*
+-		 * ->iopoll_list is protected by the ctx->uring_lock for
+-		 * io_uring instances that don't use IORING_SETUP_SQPOLL.
+-		 * For SQPOLL, only the single threaded io_sq_thread() will
+-		 * manipulate the list, hence no extra locking is needed there.
+-		 */
+-		struct list_head	iopoll_list;
+-		struct hlist_head	*cancel_hash;
+-		unsigned		cancel_hash_bits;
+-		bool			poll_multi_queue;
+-	} ____cacheline_aligned_in_smp;
+-
+-	struct io_restriction		restrictions;
+-
+-	/* slow path rsrc auxilary data, used by update/register */
+-	struct {
+-		struct io_rsrc_node		*rsrc_backup_node;
+-		struct io_mapped_ubuf		*dummy_ubuf;
+-		struct io_rsrc_data		*file_data;
+-		struct io_rsrc_data		*buf_data;
+-
+-		struct delayed_work		rsrc_put_work;
+-		struct llist_head		rsrc_put_llist;
+-		struct list_head		rsrc_ref_list;
+-		spinlock_t			rsrc_ref_lock;
+-	};
+-
+-	/* Keep this last, we don't need it for the fast path */
+-	struct {
+-		#if defined(CONFIG_UNIX)
+-			struct socket		*ring_sock;
+-		#endif
+-		/* hashed buffered write serialization */
+-		struct io_wq_hash		*hash_map;
+-
+-		/* Only used for accounting purposes */
+-		struct user_struct		*user;
+-		struct mm_struct		*mm_account;
+-
+-		/* ctx exit and cancelation */
+-		struct llist_head		fallback_llist;
+-		struct delayed_work		fallback_work;
+-		struct work_struct		exit_work;
+-		struct list_head		tctx_list;
+-		struct completion		ref_comp;
+-		u32				iowq_limits[2];
+-		bool				iowq_limits_set;
+-	};
+-};
+-
+-struct io_uring_task {
+-	/* submission side */
+-	int			cached_refs;
+-	struct xarray		xa;
+-	struct wait_queue_head	wait;
+-	const struct io_ring_ctx *last;
+-	struct io_wq		*io_wq;
+-	struct percpu_counter	inflight;
+-	atomic_t		inflight_tracked;
+-	atomic_t		in_idle;
+-
+-	spinlock_t		task_lock;
+-	struct io_wq_work_list	task_list;
+-	struct callback_head	task_work;
+-	bool			task_running;
+-};
+-
+-/*
+- * First field must be the file pointer in all the
+- * iocb unions! See also 'struct kiocb' in <linux/fs.h>
+- */
+-struct io_poll_iocb {
+-	struct file			*file;
+-	struct wait_queue_head		*head;
+-	__poll_t			events;
+-	struct wait_queue_entry		wait;
+-};
+-
+-struct io_poll_update {
+-	struct file			*file;
+-	u64				old_user_data;
+-	u64				new_user_data;
+-	__poll_t			events;
+-	bool				update_events;
+-	bool				update_user_data;
+-};
+-
+-struct io_close {
+-	struct file			*file;
+-	int				fd;
+-	u32				file_slot;
+-};
+-
+-struct io_timeout_data {
+-	struct io_kiocb			*req;
+-	struct hrtimer			timer;
+-	struct timespec64		ts;
+-	enum hrtimer_mode		mode;
+-	u32				flags;
+-};
+-
+-struct io_accept {
+-	struct file			*file;
+-	struct sockaddr __user		*addr;
+-	int __user			*addr_len;
+-	int				flags;
+-	u32				file_slot;
+-	unsigned long			nofile;
+-};
+-
+-struct io_sync {
+-	struct file			*file;
+-	loff_t				len;
+-	loff_t				off;
+-	int				flags;
+-	int				mode;
+-};
+-
+-struct io_cancel {
+-	struct file			*file;
+-	u64				addr;
+-};
+-
+-struct io_timeout {
+-	struct file			*file;
+-	u32				off;
+-	u32				target_seq;
+-	struct list_head		list;
+-	/* head of the link, used by linked timeouts only */
+-	struct io_kiocb			*head;
+-	/* for linked completions */
+-	struct io_kiocb			*prev;
+-};
+-
+-struct io_timeout_rem {
+-	struct file			*file;
+-	u64				addr;
+-
+-	/* timeout update */
+-	struct timespec64		ts;
+-	u32				flags;
+-	bool				ltimeout;
+-};
+-
+-struct io_rw {
+-	/* NOTE: kiocb has the file as the first member, so don't do it here */
+-	struct kiocb			kiocb;
+-	u64				addr;
+-	u64				len;
+-};
+-
+-struct io_connect {
+-	struct file			*file;
+-	struct sockaddr __user		*addr;
+-	int				addr_len;
+-};
+-
+-struct io_sr_msg {
+-	struct file			*file;
+-	union {
+-		struct compat_msghdr __user	*umsg_compat;
+-		struct user_msghdr __user	*umsg;
+-		void __user			*buf;
+-	};
+-	int				msg_flags;
+-	int				bgid;
+-	size_t				len;
+-	struct io_buffer		*kbuf;
+-};
+-
+-struct io_open {
+-	struct file			*file;
+-	int				dfd;
+-	u32				file_slot;
+-	struct filename			*filename;
+-	struct open_how			how;
+-	unsigned long			nofile;
+-};
+-
+-struct io_rsrc_update {
+-	struct file			*file;
+-	u64				arg;
+-	u32				nr_args;
+-	u32				offset;
+-};
+-
+-struct io_fadvise {
+-	struct file			*file;
+-	u64				offset;
+-	u32				len;
+-	u32				advice;
+-};
+-
+-struct io_madvise {
+-	struct file			*file;
+-	u64				addr;
+-	u32				len;
+-	u32				advice;
+-};
+-
+-struct io_epoll {
+-	struct file			*file;
+-	int				epfd;
+-	int				op;
+-	int				fd;
+-	struct epoll_event		event;
+-};
+-
+-struct io_splice {
+-	struct file			*file_out;
+-	loff_t				off_out;
+-	loff_t				off_in;
+-	u64				len;
+-	int				splice_fd_in;
+-	unsigned int			flags;
+-};
+-
+-struct io_provide_buf {
+-	struct file			*file;
+-	__u64				addr;
+-	__u32				len;
+-	__u32				bgid;
+-	__u16				nbufs;
+-	__u16				bid;
+-};
+-
+-struct io_statx {
+-	struct file			*file;
+-	int				dfd;
+-	unsigned int			mask;
+-	unsigned int			flags;
+-	const char __user		*filename;
+-	struct statx __user		*buffer;
+-};
+-
+-struct io_shutdown {
+-	struct file			*file;
+-	int				how;
+-};
+-
+-struct io_rename {
+-	struct file			*file;
+-	int				old_dfd;
+-	int				new_dfd;
+-	struct filename			*oldpath;
+-	struct filename			*newpath;
+-	int				flags;
+-};
+-
+-struct io_unlink {
+-	struct file			*file;
+-	int				dfd;
+-	int				flags;
+-	struct filename			*filename;
+-};
+-
+-struct io_mkdir {
+-	struct file			*file;
+-	int				dfd;
+-	umode_t				mode;
+-	struct filename			*filename;
+-};
+-
+-struct io_symlink {
+-	struct file			*file;
+-	int				new_dfd;
+-	struct filename			*oldpath;
+-	struct filename			*newpath;
+-};
+-
+-struct io_hardlink {
+-	struct file			*file;
+-	int				old_dfd;
+-	int				new_dfd;
+-	struct filename			*oldpath;
+-	struct filename			*newpath;
+-	int				flags;
+-};
+-
+-struct io_completion {
+-	struct file			*file;
+-	u32				cflags;
+-};
+-
+-struct io_async_connect {
+-	struct sockaddr_storage		address;
+-};
+-
+-struct io_async_msghdr {
+-	struct iovec			fast_iov[UIO_FASTIOV];
+-	/* points to an allocated iov, if NULL we use fast_iov instead */
+-	struct iovec			*free_iov;
+-	struct sockaddr __user		*uaddr;
+-	struct msghdr			msg;
+-	struct sockaddr_storage		addr;
+-};
+-
+-struct io_async_rw {
+-	struct iovec			fast_iov[UIO_FASTIOV];
+-	const struct iovec		*free_iovec;
+-	struct iov_iter			iter;
+-	struct iov_iter_state		iter_state;
+-	size_t				bytes_done;
+-	struct wait_page_queue		wpq;
+-};
+-
+-enum {
+-	REQ_F_FIXED_FILE_BIT	= IOSQE_FIXED_FILE_BIT,
+-	REQ_F_IO_DRAIN_BIT	= IOSQE_IO_DRAIN_BIT,
+-	REQ_F_LINK_BIT		= IOSQE_IO_LINK_BIT,
+-	REQ_F_HARDLINK_BIT	= IOSQE_IO_HARDLINK_BIT,
+-	REQ_F_FORCE_ASYNC_BIT	= IOSQE_ASYNC_BIT,
+-	REQ_F_BUFFER_SELECT_BIT	= IOSQE_BUFFER_SELECT_BIT,
+-
+-	/* first byte is taken by user flags, shift it to not overlap */
+-	REQ_F_FAIL_BIT		= 8,
+-	REQ_F_INFLIGHT_BIT,
+-	REQ_F_CUR_POS_BIT,
+-	REQ_F_NOWAIT_BIT,
+-	REQ_F_LINK_TIMEOUT_BIT,
+-	REQ_F_NEED_CLEANUP_BIT,
+-	REQ_F_POLLED_BIT,
+-	REQ_F_BUFFER_SELECTED_BIT,
+-	REQ_F_COMPLETE_INLINE_BIT,
+-	REQ_F_REISSUE_BIT,
+-	REQ_F_CREDS_BIT,
+-	REQ_F_REFCOUNT_BIT,
+-	REQ_F_ARM_LTIMEOUT_BIT,
+-	/* keep async read/write and isreg together and in order */
+-	REQ_F_NOWAIT_READ_BIT,
+-	REQ_F_NOWAIT_WRITE_BIT,
+-	REQ_F_ISREG_BIT,
+-
+-	/* not a real bit, just to check we're not overflowing the space */
+-	__REQ_F_LAST_BIT,
+-};
+-
+-enum {
+-	/* ctx owns file */
+-	REQ_F_FIXED_FILE	= BIT(REQ_F_FIXED_FILE_BIT),
+-	/* drain existing IO first */
+-	REQ_F_IO_DRAIN		= BIT(REQ_F_IO_DRAIN_BIT),
+-	/* linked sqes */
+-	REQ_F_LINK		= BIT(REQ_F_LINK_BIT),
+-	/* doesn't sever on completion < 0 */
+-	REQ_F_HARDLINK		= BIT(REQ_F_HARDLINK_BIT),
+-	/* IOSQE_ASYNC */
+-	REQ_F_FORCE_ASYNC	= BIT(REQ_F_FORCE_ASYNC_BIT),
+-	/* IOSQE_BUFFER_SELECT */
+-	REQ_F_BUFFER_SELECT	= BIT(REQ_F_BUFFER_SELECT_BIT),
+-
+-	/* fail rest of links */
+-	REQ_F_FAIL		= BIT(REQ_F_FAIL_BIT),
+-	/* on inflight list, should be cancelled and waited on exit reliably */
+-	REQ_F_INFLIGHT		= BIT(REQ_F_INFLIGHT_BIT),
+-	/* read/write uses file position */
+-	REQ_F_CUR_POS		= BIT(REQ_F_CUR_POS_BIT),
+-	/* must not punt to workers */
+-	REQ_F_NOWAIT		= BIT(REQ_F_NOWAIT_BIT),
+-	/* has or had linked timeout */
+-	REQ_F_LINK_TIMEOUT	= BIT(REQ_F_LINK_TIMEOUT_BIT),
+-	/* needs cleanup */
+-	REQ_F_NEED_CLEANUP	= BIT(REQ_F_NEED_CLEANUP_BIT),
+-	/* already went through poll handler */
+-	REQ_F_POLLED		= BIT(REQ_F_POLLED_BIT),
+-	/* buffer already selected */
+-	REQ_F_BUFFER_SELECTED	= BIT(REQ_F_BUFFER_SELECTED_BIT),
+-	/* completion is deferred through io_comp_state */
+-	REQ_F_COMPLETE_INLINE	= BIT(REQ_F_COMPLETE_INLINE_BIT),
+-	/* caller should reissue async */
+-	REQ_F_REISSUE		= BIT(REQ_F_REISSUE_BIT),
+-	/* supports async reads */
+-	REQ_F_NOWAIT_READ	= BIT(REQ_F_NOWAIT_READ_BIT),
+-	/* supports async writes */
+-	REQ_F_NOWAIT_WRITE	= BIT(REQ_F_NOWAIT_WRITE_BIT),
+-	/* regular file */
+-	REQ_F_ISREG		= BIT(REQ_F_ISREG_BIT),
+-	/* has creds assigned */
+-	REQ_F_CREDS		= BIT(REQ_F_CREDS_BIT),
+-	/* skip refcounting if not set */
+-	REQ_F_REFCOUNT		= BIT(REQ_F_REFCOUNT_BIT),
+-	/* there is a linked timeout that has to be armed */
+-	REQ_F_ARM_LTIMEOUT	= BIT(REQ_F_ARM_LTIMEOUT_BIT),
+-};
+-
+-struct async_poll {
+-	struct io_poll_iocb	poll;
+-	struct io_poll_iocb	*double_poll;
+-};
+-
+-typedef void (*io_req_tw_func_t)(struct io_kiocb *req, bool *locked);
+-
+-struct io_task_work {
+-	union {
+-		struct io_wq_work_node	node;
+-		struct llist_node	fallback_node;
+-	};
+-	io_req_tw_func_t		func;
+-};
+-
+-enum {
+-	IORING_RSRC_FILE		= 0,
+-	IORING_RSRC_BUFFER		= 1,
+-};
+-
+-/*
+- * NOTE! Each of the iocb union members has the file pointer
+- * as the first entry in their struct definition. So you can
+- * access the file pointer through any of the sub-structs,
+- * or directly as just 'ki_filp' in this struct.
+- */
+-struct io_kiocb {
+-	union {
+-		struct file		*file;
+-		struct io_rw		rw;
+-		struct io_poll_iocb	poll;
+-		struct io_poll_update	poll_update;
+-		struct io_accept	accept;
+-		struct io_sync		sync;
+-		struct io_cancel	cancel;
+-		struct io_timeout	timeout;
+-		struct io_timeout_rem	timeout_rem;
+-		struct io_connect	connect;
+-		struct io_sr_msg	sr_msg;
+-		struct io_open		open;
+-		struct io_close		close;
+-		struct io_rsrc_update	rsrc_update;
+-		struct io_fadvise	fadvise;
+-		struct io_madvise	madvise;
+-		struct io_epoll		epoll;
+-		struct io_splice	splice;
+-		struct io_provide_buf	pbuf;
+-		struct io_statx		statx;
+-		struct io_shutdown	shutdown;
+-		struct io_rename	rename;
+-		struct io_unlink	unlink;
+-		struct io_mkdir		mkdir;
+-		struct io_symlink	symlink;
+-		struct io_hardlink	hardlink;
+-		/* use only after cleaning per-op data, see io_clean_op() */
+-		struct io_completion	compl;
+-	};
+-
+-	/* opcode allocated if it needs to store data for async defer */
+-	void				*async_data;
+-	u8				opcode;
+-	/* polled IO has completed */
+-	u8				iopoll_completed;
+-
+-	u16				buf_index;
+-	u32				result;
+-
+-	struct io_ring_ctx		*ctx;
+-	unsigned int			flags;
+-	atomic_t			refs;
+-	struct task_struct		*task;
+-	u64				user_data;
+-
+-	struct io_kiocb			*link;
+-	struct percpu_ref		*fixed_rsrc_refs;
+-
+-	/* used with ctx->iopoll_list with reads/writes */
+-	struct list_head		inflight_entry;
+-	struct io_task_work		io_task_work;
+-	/* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
+-	struct hlist_node		hash_node;
+-	struct async_poll		*apoll;
+-	struct io_wq_work		work;
+-	const struct cred		*creds;
+-
+-	/* store used ubuf, so we can prevent reloading */
+-	struct io_mapped_ubuf		*imu;
+-	/* stores selected buf, valid IFF REQ_F_BUFFER_SELECTED is set */
+-	struct io_buffer		*kbuf;
+-	atomic_t			poll_refs;
+-};
+-
+-struct io_tctx_node {
+-	struct list_head	ctx_node;
+-	struct task_struct	*task;
+-	struct io_ring_ctx	*ctx;
+-};
+-
+-struct io_defer_entry {
+-	struct list_head	list;
+-	struct io_kiocb		*req;
+-	u32			seq;
+-};
+-
+-struct io_op_def {
+-	/* needs req->file assigned */
+-	unsigned		needs_file : 1;
+-	/* hash wq insertion if file is a regular file */
+-	unsigned		hash_reg_file : 1;
+-	/* unbound wq insertion if file is a non-regular file */
+-	unsigned		unbound_nonreg_file : 1;
+-	/* opcode is not supported by this kernel */
+-	unsigned		not_supported : 1;
+-	/* set if opcode supports polled "wait" */
+-	unsigned		pollin : 1;
+-	unsigned		pollout : 1;
+-	/* op supports buffer selection */
+-	unsigned		buffer_select : 1;
+-	/* do prep async if is going to be punted */
+-	unsigned		needs_async_setup : 1;
+-	/* should block plug */
+-	unsigned		plug : 1;
+-	/* size of async data needed, if any */
+-	unsigned short		async_size;
+-};
+-
+-static const struct io_op_def io_op_defs[] = {
+-	[IORING_OP_NOP] = {},
+-	[IORING_OP_READV] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollin			= 1,
+-		.buffer_select		= 1,
+-		.needs_async_setup	= 1,
+-		.plug			= 1,
+-		.async_size		= sizeof(struct io_async_rw),
+-	},
+-	[IORING_OP_WRITEV] = {
+-		.needs_file		= 1,
+-		.hash_reg_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollout		= 1,
+-		.needs_async_setup	= 1,
+-		.plug			= 1,
+-		.async_size		= sizeof(struct io_async_rw),
+-	},
+-	[IORING_OP_FSYNC] = {
+-		.needs_file		= 1,
+-	},
+-	[IORING_OP_READ_FIXED] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollin			= 1,
+-		.plug			= 1,
+-		.async_size		= sizeof(struct io_async_rw),
+-	},
+-	[IORING_OP_WRITE_FIXED] = {
+-		.needs_file		= 1,
+-		.hash_reg_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollout		= 1,
+-		.plug			= 1,
+-		.async_size		= sizeof(struct io_async_rw),
+-	},
+-	[IORING_OP_POLL_ADD] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-	},
+-	[IORING_OP_POLL_REMOVE] = {},
+-	[IORING_OP_SYNC_FILE_RANGE] = {
+-		.needs_file		= 1,
+-	},
+-	[IORING_OP_SENDMSG] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollout		= 1,
+-		.needs_async_setup	= 1,
+-		.async_size		= sizeof(struct io_async_msghdr),
+-	},
+-	[IORING_OP_RECVMSG] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollin			= 1,
+-		.buffer_select		= 1,
+-		.needs_async_setup	= 1,
+-		.async_size		= sizeof(struct io_async_msghdr),
+-	},
+-	[IORING_OP_TIMEOUT] = {
+-		.async_size		= sizeof(struct io_timeout_data),
+-	},
+-	[IORING_OP_TIMEOUT_REMOVE] = {
+-		/* used by timeout updates' prep() */
+-	},
+-	[IORING_OP_ACCEPT] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollin			= 1,
+-	},
+-	[IORING_OP_ASYNC_CANCEL] = {},
+-	[IORING_OP_LINK_TIMEOUT] = {
+-		.async_size		= sizeof(struct io_timeout_data),
+-	},
+-	[IORING_OP_CONNECT] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollout		= 1,
+-		.needs_async_setup	= 1,
+-		.async_size		= sizeof(struct io_async_connect),
+-	},
+-	[IORING_OP_FALLOCATE] = {
+-		.needs_file		= 1,
+-	},
+-	[IORING_OP_OPENAT] = {},
+-	[IORING_OP_CLOSE] = {},
+-	[IORING_OP_FILES_UPDATE] = {},
+-	[IORING_OP_STATX] = {},
+-	[IORING_OP_READ] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollin			= 1,
+-		.buffer_select		= 1,
+-		.plug			= 1,
+-		.async_size		= sizeof(struct io_async_rw),
+-	},
+-	[IORING_OP_WRITE] = {
+-		.needs_file		= 1,
+-		.hash_reg_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollout		= 1,
+-		.plug			= 1,
+-		.async_size		= sizeof(struct io_async_rw),
+-	},
+-	[IORING_OP_FADVISE] = {
+-		.needs_file		= 1,
+-	},
+-	[IORING_OP_MADVISE] = {},
+-	[IORING_OP_SEND] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollout		= 1,
+-	},
+-	[IORING_OP_RECV] = {
+-		.needs_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-		.pollin			= 1,
+-		.buffer_select		= 1,
+-	},
+-	[IORING_OP_OPENAT2] = {
+-	},
+-	[IORING_OP_EPOLL_CTL] = {
+-		.unbound_nonreg_file	= 1,
+-	},
+-	[IORING_OP_SPLICE] = {
+-		.needs_file		= 1,
+-		.hash_reg_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-	},
+-	[IORING_OP_PROVIDE_BUFFERS] = {},
+-	[IORING_OP_REMOVE_BUFFERS] = {},
+-	[IORING_OP_TEE] = {
+-		.needs_file		= 1,
+-		.hash_reg_file		= 1,
+-		.unbound_nonreg_file	= 1,
+-	},
+-	[IORING_OP_SHUTDOWN] = {
+-		.needs_file		= 1,
+-	},
+-	[IORING_OP_RENAMEAT] = {},
+-	[IORING_OP_UNLINKAT] = {},
+-	[IORING_OP_MKDIRAT] = {},
+-	[IORING_OP_SYMLINKAT] = {},
+-	[IORING_OP_LINKAT] = {},
+-};
+-
+-/* requests with any of those set should undergo io_disarm_next() */
+-#define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
+-
+-static bool io_disarm_next(struct io_kiocb *req);
+-static void io_uring_del_tctx_node(unsigned long index);
+-static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
+-					 struct task_struct *task,
+-					 bool cancel_all);
+-static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
+-
+-static void io_fill_cqe_req(struct io_kiocb *req, s32 res, u32 cflags);
+-
+-static void io_put_req(struct io_kiocb *req);
+-static void io_put_req_deferred(struct io_kiocb *req);
+-static void io_dismantle_req(struct io_kiocb *req);
+-static void io_queue_linked_timeout(struct io_kiocb *req);
+-static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
+-				     struct io_uring_rsrc_update2 *up,
+-				     unsigned nr_args);
+-static void io_clean_op(struct io_kiocb *req);
+-static struct file *io_file_get(struct io_ring_ctx *ctx,
+-				struct io_kiocb *req, int fd, bool fixed);
+-static void __io_queue_sqe(struct io_kiocb *req);
+-static void io_rsrc_put_work(struct work_struct *work);
+-
+-static void io_req_task_queue(struct io_kiocb *req);
+-static void io_submit_flush_completions(struct io_ring_ctx *ctx);
+-static int io_req_prep_async(struct io_kiocb *req);
+-
+-static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
+-				 unsigned int issue_flags, u32 slot_index);
+-static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags);
+-
+-static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer);
+-
+-static struct kmem_cache *req_cachep;
+-
+-static const struct file_operations io_uring_fops;
+-
+-struct sock *io_uring_get_socket(struct file *file)
+-{
+-#if defined(CONFIG_UNIX)
+-	if (file->f_op == &io_uring_fops) {
+-		struct io_ring_ctx *ctx = file->private_data;
+-
+-		return ctx->ring_sock->sk;
+-	}
+-#endif
+-	return NULL;
+-}
+-EXPORT_SYMBOL(io_uring_get_socket);
+-
+-static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked)
+-{
+-	if (!*locked) {
+-		mutex_lock(&ctx->uring_lock);
+-		*locked = true;
+-	}
+-}
+-
+-#define io_for_each_link(pos, head) \
+-	for (pos = (head); pos; pos = pos->link)
+-
+-/*
+- * Shamelessly stolen from the mm implementation of page reference checking,
+- * see commit f958d7b528b1 for details.
+- */
+-#define req_ref_zero_or_close_to_overflow(req)	\
+-	((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
+-
+-static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
+-{
+-	WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
+-	return atomic_inc_not_zero(&req->refs);
+-}
+-
+-static inline bool req_ref_put_and_test(struct io_kiocb *req)
+-{
+-	if (likely(!(req->flags & REQ_F_REFCOUNT)))
+-		return true;
+-
+-	WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
+-	return atomic_dec_and_test(&req->refs);
+-}
+-
+-static inline void req_ref_get(struct io_kiocb *req)
+-{
+-	WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
+-	WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
+-	atomic_inc(&req->refs);
+-}
+-
+-static inline void __io_req_set_refcount(struct io_kiocb *req, int nr)
+-{
+-	if (!(req->flags & REQ_F_REFCOUNT)) {
+-		req->flags |= REQ_F_REFCOUNT;
+-		atomic_set(&req->refs, nr);
+-	}
+-}
+-
+-static inline void io_req_set_refcount(struct io_kiocb *req)
+-{
+-	__io_req_set_refcount(req, 1);
+-}
+-
+-static inline void io_req_set_rsrc_node(struct io_kiocb *req)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	if (!req->fixed_rsrc_refs) {
+-		req->fixed_rsrc_refs = &ctx->rsrc_node->refs;
+-		percpu_ref_get(req->fixed_rsrc_refs);
+-	}
+-}
+-
+-static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl)
+-{
+-	bool got = percpu_ref_tryget(ref);
+-
+-	/* already at zero, wait for ->release() */
+-	if (!got)
+-		wait_for_completion(compl);
+-	percpu_ref_resurrect(ref);
+-	if (got)
+-		percpu_ref_put(ref);
+-}
+-
+-static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
+-			  bool cancel_all)
+-	__must_hold(&req->ctx->timeout_lock)
+-{
+-	struct io_kiocb *req;
+-
+-	if (task && head->task != task)
+-		return false;
+-	if (cancel_all)
+-		return true;
+-
+-	io_for_each_link(req, head) {
+-		if (req->flags & REQ_F_INFLIGHT)
+-			return true;
+-	}
+-	return false;
+-}
+-
+-static bool io_match_linked(struct io_kiocb *head)
+-{
+-	struct io_kiocb *req;
+-
+-	io_for_each_link(req, head) {
+-		if (req->flags & REQ_F_INFLIGHT)
+-			return true;
+-	}
+-	return false;
+-}
+-
+-/*
+- * As io_match_task() but protected against racing with linked timeouts.
+- * User must not hold timeout_lock.
+- */
+-static bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
+-			       bool cancel_all)
+-{
+-	bool matched;
+-
+-	if (task && head->task != task)
+-		return false;
+-	if (cancel_all)
+-		return true;
+-
+-	if (head->flags & REQ_F_LINK_TIMEOUT) {
+-		struct io_ring_ctx *ctx = head->ctx;
+-
+-		/* protect against races with linked timeouts */
+-		spin_lock_irq(&ctx->timeout_lock);
+-		matched = io_match_linked(head);
+-		spin_unlock_irq(&ctx->timeout_lock);
+-	} else {
+-		matched = io_match_linked(head);
+-	}
+-	return matched;
+-}
+-
+-static inline void req_set_fail(struct io_kiocb *req)
+-{
+-	req->flags |= REQ_F_FAIL;
+-}
+-
+-static inline void req_fail_link_node(struct io_kiocb *req, int res)
+-{
+-	req_set_fail(req);
+-	req->result = res;
+-}
+-
+-static void io_ring_ctx_ref_free(struct percpu_ref *ref)
+-{
+-	struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
+-
+-	complete(&ctx->ref_comp);
+-}
+-
+-static inline bool io_is_timeout_noseq(struct io_kiocb *req)
+-{
+-	return !req->timeout.off;
+-}
+-
+-static void io_fallback_req_func(struct work_struct *work)
+-{
+-	struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
+-						fallback_work.work);
+-	struct llist_node *node = llist_del_all(&ctx->fallback_llist);
+-	struct io_kiocb *req, *tmp;
+-	bool locked = false;
+-
+-	percpu_ref_get(&ctx->refs);
+-	llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node)
+-		req->io_task_work.func(req, &locked);
+-
+-	if (locked) {
+-		if (ctx->submit_state.compl_nr)
+-			io_submit_flush_completions(ctx);
+-		mutex_unlock(&ctx->uring_lock);
+-	}
+-	percpu_ref_put(&ctx->refs);
+-
+-}
+-
+-static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
+-{
+-	struct io_ring_ctx *ctx;
+-	int hash_bits;
+-
+-	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+-	if (!ctx)
+-		return NULL;
+-
+-	/*
+-	 * Use 5 bits less than the max cq entries, that should give us around
+-	 * 32 entries per hash list if totally full and uniformly spread.
+-	 */
+-	hash_bits = ilog2(p->cq_entries);
+-	hash_bits -= 5;
+-	if (hash_bits <= 0)
+-		hash_bits = 1;
+-	ctx->cancel_hash_bits = hash_bits;
+-	ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
+-					GFP_KERNEL);
+-	if (!ctx->cancel_hash)
+-		goto err;
+-	__hash_init(ctx->cancel_hash, 1U << hash_bits);
+-
+-	ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL);
+-	if (!ctx->dummy_ubuf)
+-		goto err;
+-	/* set invalid range, so io_import_fixed() fails meeting it */
+-	ctx->dummy_ubuf->ubuf = -1UL;
+-
+-	if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
+-			    PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
+-		goto err;
+-
+-	ctx->flags = p->flags;
+-	init_waitqueue_head(&ctx->sqo_sq_wait);
+-	INIT_LIST_HEAD(&ctx->sqd_list);
+-	init_waitqueue_head(&ctx->poll_wait);
+-	INIT_LIST_HEAD(&ctx->cq_overflow_list);
+-	init_completion(&ctx->ref_comp);
+-	xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
+-	xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
+-	mutex_init(&ctx->uring_lock);
+-	init_waitqueue_head(&ctx->cq_wait);
+-	spin_lock_init(&ctx->completion_lock);
+-	spin_lock_init(&ctx->timeout_lock);
+-	INIT_LIST_HEAD(&ctx->iopoll_list);
+-	INIT_LIST_HEAD(&ctx->defer_list);
+-	INIT_LIST_HEAD(&ctx->timeout_list);
+-	INIT_LIST_HEAD(&ctx->ltimeout_list);
+-	spin_lock_init(&ctx->rsrc_ref_lock);
+-	INIT_LIST_HEAD(&ctx->rsrc_ref_list);
+-	INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
+-	init_llist_head(&ctx->rsrc_put_llist);
+-	INIT_LIST_HEAD(&ctx->tctx_list);
+-	INIT_LIST_HEAD(&ctx->submit_state.free_list);
+-	INIT_LIST_HEAD(&ctx->locked_free_list);
+-	INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func);
+-	return ctx;
+-err:
+-	kfree(ctx->dummy_ubuf);
+-	kfree(ctx->cancel_hash);
+-	kfree(ctx);
+-	return NULL;
+-}
+-
+-static void io_account_cq_overflow(struct io_ring_ctx *ctx)
+-{
+-	struct io_rings *r = ctx->rings;
+-
+-	WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1);
+-	ctx->cq_extra--;
+-}
+-
+-static bool req_need_defer(struct io_kiocb *req, u32 seq)
+-{
+-	if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
+-		struct io_ring_ctx *ctx = req->ctx;
+-
+-		return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail;
+-	}
+-
+-	return false;
+-}
+-
+-#define FFS_ASYNC_READ		0x1UL
+-#define FFS_ASYNC_WRITE		0x2UL
+-#ifdef CONFIG_64BIT
+-#define FFS_ISREG		0x4UL
+-#else
+-#define FFS_ISREG		0x0UL
+-#endif
+-#define FFS_MASK		~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
+-
+-static inline bool io_req_ffs_set(struct io_kiocb *req)
+-{
+-	return IS_ENABLED(CONFIG_64BIT) && (req->flags & REQ_F_FIXED_FILE);
+-}
+-
+-static void io_req_track_inflight(struct io_kiocb *req)
+-{
+-	if (!(req->flags & REQ_F_INFLIGHT)) {
+-		req->flags |= REQ_F_INFLIGHT;
+-		atomic_inc(&req->task->io_uring->inflight_tracked);
+-	}
+-}
+-
+-static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req)
+-{
+-	if (WARN_ON_ONCE(!req->link))
+-		return NULL;
+-
+-	req->flags &= ~REQ_F_ARM_LTIMEOUT;
+-	req->flags |= REQ_F_LINK_TIMEOUT;
+-
+-	/* linked timeouts should have two refs once prep'ed */
+-	io_req_set_refcount(req);
+-	__io_req_set_refcount(req->link, 2);
+-	return req->link;
+-}
+-
+-static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
+-{
+-	if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT)))
+-		return NULL;
+-	return __io_prep_linked_timeout(req);
+-}
+-
+-static void io_prep_async_work(struct io_kiocb *req)
+-{
+-	const struct io_op_def *def = &io_op_defs[req->opcode];
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	if (!(req->flags & REQ_F_CREDS)) {
+-		req->flags |= REQ_F_CREDS;
+-		req->creds = get_current_cred();
+-	}
+-
+-	req->work.list.next = NULL;
+-	req->work.flags = 0;
+-	if (req->flags & REQ_F_FORCE_ASYNC)
+-		req->work.flags |= IO_WQ_WORK_CONCURRENT;
+-
+-	if (req->flags & REQ_F_ISREG) {
+-		if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
+-			io_wq_hash_work(&req->work, file_inode(req->file));
+-	} else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
+-		if (def->unbound_nonreg_file)
+-			req->work.flags |= IO_WQ_WORK_UNBOUND;
+-	}
+-}
+-
+-static void io_prep_async_link(struct io_kiocb *req)
+-{
+-	struct io_kiocb *cur;
+-
+-	if (req->flags & REQ_F_LINK_TIMEOUT) {
+-		struct io_ring_ctx *ctx = req->ctx;
+-
+-		spin_lock_irq(&ctx->timeout_lock);
+-		io_for_each_link(cur, req)
+-			io_prep_async_work(cur);
+-		spin_unlock_irq(&ctx->timeout_lock);
+-	} else {
+-		io_for_each_link(cur, req)
+-			io_prep_async_work(cur);
+-	}
+-}
+-
+-static void io_queue_async_work(struct io_kiocb *req, bool *locked)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_kiocb *link = io_prep_linked_timeout(req);
+-	struct io_uring_task *tctx = req->task->io_uring;
+-
+-	/* must not take the lock, NULL it as a precaution */
+-	locked = NULL;
+-
+-	BUG_ON(!tctx);
+-	BUG_ON(!tctx->io_wq);
+-
+-	/* init ->work of the whole link before punting */
+-	io_prep_async_link(req);
+-
+-	/*
+-	 * Not expected to happen, but if we do have a bug where this _can_
+-	 * happen, catch it here and ensure the request is marked as
+-	 * canceled. That will make io-wq go through the usual work cancel
+-	 * procedure rather than attempt to run this request (or create a new
+-	 * worker for it).
+-	 */
+-	if (WARN_ON_ONCE(!same_thread_group(req->task, current)))
+-		req->work.flags |= IO_WQ_WORK_CANCEL;
+-
+-	trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
+-					&req->work, req->flags);
+-	io_wq_enqueue(tctx->io_wq, &req->work);
+-	if (link)
+-		io_queue_linked_timeout(link);
+-}
+-
+-static void io_kill_timeout(struct io_kiocb *req, int status)
+-	__must_hold(&req->ctx->completion_lock)
+-	__must_hold(&req->ctx->timeout_lock)
+-{
+-	struct io_timeout_data *io = req->async_data;
+-
+-	if (hrtimer_try_to_cancel(&io->timer) != -1) {
+-		if (status)
+-			req_set_fail(req);
+-		atomic_set(&req->ctx->cq_timeouts,
+-			atomic_read(&req->ctx->cq_timeouts) + 1);
+-		list_del_init(&req->timeout.list);
+-		io_fill_cqe_req(req, status, 0);
+-		io_put_req_deferred(req);
+-	}
+-}
+-
+-static void io_queue_deferred(struct io_ring_ctx *ctx)
+-{
+-	while (!list_empty(&ctx->defer_list)) {
+-		struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
+-						struct io_defer_entry, list);
+-
+-		if (req_need_defer(de->req, de->seq))
+-			break;
+-		list_del_init(&de->list);
+-		io_req_task_queue(de->req);
+-		kfree(de);
+-	}
+-}
+-
+-static void io_flush_timeouts(struct io_ring_ctx *ctx)
+-	__must_hold(&ctx->completion_lock)
+-{
+-	u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
+-	struct io_kiocb *req, *tmp;
+-
+-	spin_lock_irq(&ctx->timeout_lock);
+-	list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
+-		u32 events_needed, events_got;
+-
+-		if (io_is_timeout_noseq(req))
+-			break;
+-
+-		/*
+-		 * Since seq can easily wrap around over time, subtract
+-		 * the last seq at which timeouts were flushed before comparing.
+-		 * Assuming not more than 2^31-1 events have happened since,
+-		 * these subtractions won't have wrapped, so we can check if
+-		 * target is in [last_seq, current_seq] by comparing the two.
+-		 */
+-		events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
+-		events_got = seq - ctx->cq_last_tm_flush;
+-		if (events_got < events_needed)
+-			break;
+-
+-		io_kill_timeout(req, 0);
+-	}
+-	ctx->cq_last_tm_flush = seq;
+-	spin_unlock_irq(&ctx->timeout_lock);
+-}
+-
+-static void __io_commit_cqring_flush(struct io_ring_ctx *ctx)
+-{
+-	if (ctx->off_timeout_used)
+-		io_flush_timeouts(ctx);
+-	if (ctx->drain_active)
+-		io_queue_deferred(ctx);
+-}
+-
+-static inline void io_commit_cqring(struct io_ring_ctx *ctx)
+-{
+-	if (unlikely(ctx->off_timeout_used || ctx->drain_active))
+-		__io_commit_cqring_flush(ctx);
+-	/* order cqe stores with ring update */
+-	smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
+-}
+-
+-static inline bool io_sqring_full(struct io_ring_ctx *ctx)
+-{
+-	struct io_rings *r = ctx->rings;
+-
+-	return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
+-}
+-
+-static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
+-{
+-	return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
+-}
+-
+-static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx)
+-{
+-	struct io_rings *rings = ctx->rings;
+-	unsigned tail, mask = ctx->cq_entries - 1;
+-
+-	/*
+-	 * writes to the cq entry need to come after reading head; the
+-	 * control dependency is enough as we're using WRITE_ONCE to
+-	 * fill the cq entry
+-	 */
+-	if (__io_cqring_events(ctx) == ctx->cq_entries)
+-		return NULL;
+-
+-	tail = ctx->cached_cq_tail++;
+-	return &rings->cqes[tail & mask];
+-}
+-
+-static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
+-{
+-	if (likely(!ctx->cq_ev_fd))
+-		return false;
+-	if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
+-		return false;
+-	return !ctx->eventfd_async || io_wq_current_is_worker();
+-}
+-
+-/*
+- * This should only get called when at least one event has been posted.
+- * Some applications rely on the eventfd notification count only changing
+- * IFF a new CQE has been added to the CQ ring. There's no depedency on
+- * 1:1 relationship between how many times this function is called (and
+- * hence the eventfd count) and number of CQEs posted to the CQ ring.
+- */
+-static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
+-{
+-	/*
+-	 * wake_up_all() may seem excessive, but io_wake_function() and
+-	 * io_should_wake() handle the termination of the loop and only
+-	 * wake as many waiters as we need to.
+-	 */
+-	if (wq_has_sleeper(&ctx->cq_wait))
+-		wake_up_all(&ctx->cq_wait);
+-	if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
+-		wake_up(&ctx->sq_data->wait);
+-	if (io_should_trigger_evfd(ctx))
+-		eventfd_signal(ctx->cq_ev_fd, 1);
+-	if (waitqueue_active(&ctx->poll_wait))
+-		wake_up_interruptible(&ctx->poll_wait);
+-}
+-
+-static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
+-{
+-	/* see waitqueue_active() comment */
+-	smp_mb();
+-
+-	if (ctx->flags & IORING_SETUP_SQPOLL) {
+-		if (waitqueue_active(&ctx->cq_wait))
+-			wake_up_all(&ctx->cq_wait);
+-	}
+-	if (io_should_trigger_evfd(ctx))
+-		eventfd_signal(ctx->cq_ev_fd, 1);
+-	if (waitqueue_active(&ctx->poll_wait))
+-		wake_up_interruptible(&ctx->poll_wait);
+-}
+-
+-/* Returns true if there are no backlogged entries after the flush */
+-static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
+-{
+-	bool all_flushed, posted;
+-
+-	if (!force && __io_cqring_events(ctx) == ctx->cq_entries)
+-		return false;
+-
+-	posted = false;
+-	spin_lock(&ctx->completion_lock);
+-	while (!list_empty(&ctx->cq_overflow_list)) {
+-		struct io_uring_cqe *cqe = io_get_cqe(ctx);
+-		struct io_overflow_cqe *ocqe;
+-
+-		if (!cqe && !force)
+-			break;
+-		ocqe = list_first_entry(&ctx->cq_overflow_list,
+-					struct io_overflow_cqe, list);
+-		if (cqe)
+-			memcpy(cqe, &ocqe->cqe, sizeof(*cqe));
+-		else
+-			io_account_cq_overflow(ctx);
+-
+-		posted = true;
+-		list_del(&ocqe->list);
+-		kfree(ocqe);
+-	}
+-
+-	all_flushed = list_empty(&ctx->cq_overflow_list);
+-	if (all_flushed) {
+-		clear_bit(0, &ctx->check_cq_overflow);
+-		WRITE_ONCE(ctx->rings->sq_flags,
+-			   ctx->rings->sq_flags & ~IORING_SQ_CQ_OVERFLOW);
+-	}
+-
+-	if (posted)
+-		io_commit_cqring(ctx);
+-	spin_unlock(&ctx->completion_lock);
+-	if (posted)
+-		io_cqring_ev_posted(ctx);
+-	return all_flushed;
+-}
+-
+-static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx)
+-{
+-	bool ret = true;
+-
+-	if (test_bit(0, &ctx->check_cq_overflow)) {
+-		/* iopoll syncs against uring_lock, not completion_lock */
+-		if (ctx->flags & IORING_SETUP_IOPOLL)
+-			mutex_lock(&ctx->uring_lock);
+-		ret = __io_cqring_overflow_flush(ctx, false);
+-		if (ctx->flags & IORING_SETUP_IOPOLL)
+-			mutex_unlock(&ctx->uring_lock);
+-	}
+-
+-	return ret;
+-}
+-
+-/* must to be called somewhat shortly after putting a request */
+-static inline void io_put_task(struct task_struct *task, int nr)
+-{
+-	struct io_uring_task *tctx = task->io_uring;
+-
+-	if (likely(task == current)) {
+-		tctx->cached_refs += nr;
+-	} else {
+-		percpu_counter_sub(&tctx->inflight, nr);
+-		if (unlikely(atomic_read(&tctx->in_idle)))
+-			wake_up(&tctx->wait);
+-		put_task_struct_many(task, nr);
+-	}
+-}
+-
+-static void io_task_refs_refill(struct io_uring_task *tctx)
+-{
+-	unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR;
+-
+-	percpu_counter_add(&tctx->inflight, refill);
+-	refcount_add(refill, &current->usage);
+-	tctx->cached_refs += refill;
+-}
+-
+-static inline void io_get_task_refs(int nr)
+-{
+-	struct io_uring_task *tctx = current->io_uring;
+-
+-	tctx->cached_refs -= nr;
+-	if (unlikely(tctx->cached_refs < 0))
+-		io_task_refs_refill(tctx);
+-}
+-
+-static __cold void io_uring_drop_tctx_refs(struct task_struct *task)
+-{
+-	struct io_uring_task *tctx = task->io_uring;
+-	unsigned int refs = tctx->cached_refs;
+-
+-	if (refs) {
+-		tctx->cached_refs = 0;
+-		percpu_counter_sub(&tctx->inflight, refs);
+-		put_task_struct_many(task, refs);
+-	}
+-}
+-
+-static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data,
+-				     s32 res, u32 cflags)
+-{
+-	struct io_overflow_cqe *ocqe;
+-
+-	ocqe = kmalloc(sizeof(*ocqe), GFP_ATOMIC | __GFP_ACCOUNT);
+-	if (!ocqe) {
+-		/*
+-		 * If we're in ring overflow flush mode, or in task cancel mode,
+-		 * or cannot allocate an overflow entry, then we need to drop it
+-		 * on the floor.
+-		 */
+-		io_account_cq_overflow(ctx);
+-		return false;
+-	}
+-	if (list_empty(&ctx->cq_overflow_list)) {
+-		set_bit(0, &ctx->check_cq_overflow);
+-		WRITE_ONCE(ctx->rings->sq_flags,
+-			   ctx->rings->sq_flags | IORING_SQ_CQ_OVERFLOW);
+-
+-	}
+-	ocqe->cqe.user_data = user_data;
+-	ocqe->cqe.res = res;
+-	ocqe->cqe.flags = cflags;
+-	list_add_tail(&ocqe->list, &ctx->cq_overflow_list);
+-	return true;
+-}
+-
+-static inline bool __io_fill_cqe(struct io_ring_ctx *ctx, u64 user_data,
+-				 s32 res, u32 cflags)
+-{
+-	struct io_uring_cqe *cqe;
+-
+-	trace_io_uring_complete(ctx, user_data, res, cflags);
+-
+-	/*
+-	 * If we can't get a cq entry, userspace overflowed the
+-	 * submission (by quite a lot). Increment the overflow count in
+-	 * the ring.
+-	 */
+-	cqe = io_get_cqe(ctx);
+-	if (likely(cqe)) {
+-		WRITE_ONCE(cqe->user_data, user_data);
+-		WRITE_ONCE(cqe->res, res);
+-		WRITE_ONCE(cqe->flags, cflags);
+-		return true;
+-	}
+-	return io_cqring_event_overflow(ctx, user_data, res, cflags);
+-}
+-
+-static noinline void io_fill_cqe_req(struct io_kiocb *req, s32 res, u32 cflags)
+-{
+-	__io_fill_cqe(req->ctx, req->user_data, res, cflags);
+-}
+-
+-static noinline bool io_fill_cqe_aux(struct io_ring_ctx *ctx, u64 user_data,
+-				     s32 res, u32 cflags)
+-{
+-	ctx->cq_extra++;
+-	return __io_fill_cqe(ctx, user_data, res, cflags);
+-}
+-
+-static void io_req_complete_post(struct io_kiocb *req, s32 res,
+-				 u32 cflags)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	spin_lock(&ctx->completion_lock);
+-	__io_fill_cqe(ctx, req->user_data, res, cflags);
+-	/*
+-	 * If we're the last reference to this request, add to our locked
+-	 * free_list cache.
+-	 */
+-	if (req_ref_put_and_test(req)) {
+-		if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
+-			if (req->flags & IO_DISARM_MASK)
+-				io_disarm_next(req);
+-			if (req->link) {
+-				io_req_task_queue(req->link);
+-				req->link = NULL;
+-			}
+-		}
+-		io_dismantle_req(req);
+-		io_put_task(req->task, 1);
+-		list_add(&req->inflight_entry, &ctx->locked_free_list);
+-		ctx->locked_free_nr++;
+-	} else {
+-		if (!percpu_ref_tryget(&ctx->refs))
+-			req = NULL;
+-	}
+-	io_commit_cqring(ctx);
+-	spin_unlock(&ctx->completion_lock);
+-
+-	if (req) {
+-		io_cqring_ev_posted(ctx);
+-		percpu_ref_put(&ctx->refs);
+-	}
+-}
+-
+-static inline bool io_req_needs_clean(struct io_kiocb *req)
+-{
+-	return req->flags & IO_REQ_CLEAN_FLAGS;
+-}
+-
+-static inline void io_req_complete_state(struct io_kiocb *req, s32 res,
+-					 u32 cflags)
+-{
+-	if (io_req_needs_clean(req))
+-		io_clean_op(req);
+-	req->result = res;
+-	req->compl.cflags = cflags;
+-	req->flags |= REQ_F_COMPLETE_INLINE;
+-}
+-
+-static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
+-				     s32 res, u32 cflags)
+-{
+-	if (issue_flags & IO_URING_F_COMPLETE_DEFER)
+-		io_req_complete_state(req, res, cflags);
+-	else
+-		io_req_complete_post(req, res, cflags);
+-}
+-
+-static inline void io_req_complete(struct io_kiocb *req, s32 res)
+-{
+-	__io_req_complete(req, 0, res, 0);
+-}
+-
+-static void io_req_complete_failed(struct io_kiocb *req, s32 res)
+-{
+-	req_set_fail(req);
+-	io_req_complete_post(req, res, 0);
+-}
+-
+-static void io_req_complete_fail_submit(struct io_kiocb *req)
+-{
+-	/*
+-	 * We don't submit, fail them all, for that replace hardlinks with
+-	 * normal links. Extra REQ_F_LINK is tolerated.
+-	 */
+-	req->flags &= ~REQ_F_HARDLINK;
+-	req->flags |= REQ_F_LINK;
+-	io_req_complete_failed(req, req->result);
+-}
+-
+-/*
+- * Don't initialise the fields below on every allocation, but do that in
+- * advance and keep them valid across allocations.
+- */
+-static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx)
+-{
+-	req->ctx = ctx;
+-	req->link = NULL;
+-	req->async_data = NULL;
+-	/* not necessary, but safer to zero */
+-	req->result = 0;
+-}
+-
+-static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx,
+-					struct io_submit_state *state)
+-{
+-	spin_lock(&ctx->completion_lock);
+-	list_splice_init(&ctx->locked_free_list, &state->free_list);
+-	ctx->locked_free_nr = 0;
+-	spin_unlock(&ctx->completion_lock);
+-}
+-
+-/* Returns true IFF there are requests in the cache */
+-static bool io_flush_cached_reqs(struct io_ring_ctx *ctx)
+-{
+-	struct io_submit_state *state = &ctx->submit_state;
+-	int nr;
+-
+-	/*
+-	 * If we have more than a batch's worth of requests in our IRQ side
+-	 * locked cache, grab the lock and move them over to our submission
+-	 * side cache.
+-	 */
+-	if (READ_ONCE(ctx->locked_free_nr) > IO_COMPL_BATCH)
+-		io_flush_cached_locked_reqs(ctx, state);
+-
+-	nr = state->free_reqs;
+-	while (!list_empty(&state->free_list)) {
+-		struct io_kiocb *req = list_first_entry(&state->free_list,
+-					struct io_kiocb, inflight_entry);
+-
+-		list_del(&req->inflight_entry);
+-		state->reqs[nr++] = req;
+-		if (nr == ARRAY_SIZE(state->reqs))
+-			break;
+-	}
+-
+-	state->free_reqs = nr;
+-	return nr != 0;
+-}
+-
+-/*
+- * A request might get retired back into the request caches even before opcode
+- * handlers and io_issue_sqe() are done with it, e.g. inline completion path.
+- * Because of that, io_alloc_req() should be called only under ->uring_lock
+- * and with extra caution to not get a request that is still worked on.
+- */
+-static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
+-	__must_hold(&ctx->uring_lock)
+-{
+-	struct io_submit_state *state = &ctx->submit_state;
+-	gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
+-	int ret, i;
+-
+-	BUILD_BUG_ON(ARRAY_SIZE(state->reqs) < IO_REQ_ALLOC_BATCH);
+-
+-	if (likely(state->free_reqs || io_flush_cached_reqs(ctx)))
+-		goto got_req;
+-
+-	ret = kmem_cache_alloc_bulk(req_cachep, gfp, IO_REQ_ALLOC_BATCH,
+-				    state->reqs);
+-
+-	/*
+-	 * Bulk alloc is all-or-nothing. If we fail to get a batch,
+-	 * retry single alloc to be on the safe side.
+-	 */
+-	if (unlikely(ret <= 0)) {
+-		state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
+-		if (!state->reqs[0])
+-			return NULL;
+-		ret = 1;
+-	}
+-
+-	for (i = 0; i < ret; i++)
+-		io_preinit_req(state->reqs[i], ctx);
+-	state->free_reqs = ret;
+-got_req:
+-	state->free_reqs--;
+-	return state->reqs[state->free_reqs];
+-}
+-
+-static inline void io_put_file(struct file *file)
+-{
+-	if (file)
+-		fput(file);
+-}
+-
+-static void io_dismantle_req(struct io_kiocb *req)
+-{
+-	unsigned int flags = req->flags;
+-
+-	if (io_req_needs_clean(req))
+-		io_clean_op(req);
+-	if (!(flags & REQ_F_FIXED_FILE))
+-		io_put_file(req->file);
+-	if (req->fixed_rsrc_refs)
+-		percpu_ref_put(req->fixed_rsrc_refs);
+-	if (req->async_data) {
+-		kfree(req->async_data);
+-		req->async_data = NULL;
+-	}
+-}
+-
+-static void __io_free_req(struct io_kiocb *req)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	io_dismantle_req(req);
+-	io_put_task(req->task, 1);
+-
+-	spin_lock(&ctx->completion_lock);
+-	list_add(&req->inflight_entry, &ctx->locked_free_list);
+-	ctx->locked_free_nr++;
+-	spin_unlock(&ctx->completion_lock);
+-
+-	percpu_ref_put(&ctx->refs);
+-}
+-
+-static inline void io_remove_next_linked(struct io_kiocb *req)
+-{
+-	struct io_kiocb *nxt = req->link;
+-
+-	req->link = nxt->link;
+-	nxt->link = NULL;
+-}
+-
+-static bool io_kill_linked_timeout(struct io_kiocb *req)
+-	__must_hold(&req->ctx->completion_lock)
+-	__must_hold(&req->ctx->timeout_lock)
+-{
+-	struct io_kiocb *link = req->link;
+-
+-	if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
+-		struct io_timeout_data *io = link->async_data;
+-
+-		io_remove_next_linked(req);
+-		link->timeout.head = NULL;
+-		if (hrtimer_try_to_cancel(&io->timer) != -1) {
+-			list_del(&link->timeout.list);
+-			io_fill_cqe_req(link, -ECANCELED, 0);
+-			io_put_req_deferred(link);
+-			return true;
+-		}
+-	}
+-	return false;
+-}
+-
+-static void io_fail_links(struct io_kiocb *req)
+-	__must_hold(&req->ctx->completion_lock)
+-{
+-	struct io_kiocb *nxt, *link = req->link;
+-
+-	req->link = NULL;
+-	while (link) {
+-		long res = -ECANCELED;
+-
+-		if (link->flags & REQ_F_FAIL)
+-			res = link->result;
+-
+-		nxt = link->link;
+-		link->link = NULL;
+-
+-		trace_io_uring_fail_link(req, link);
+-		io_fill_cqe_req(link, res, 0);
+-		io_put_req_deferred(link);
+-		link = nxt;
+-	}
+-}
+-
+-static bool io_disarm_next(struct io_kiocb *req)
+-	__must_hold(&req->ctx->completion_lock)
+-{
+-	bool posted = false;
+-
+-	if (req->flags & REQ_F_ARM_LTIMEOUT) {
+-		struct io_kiocb *link = req->link;
+-
+-		req->flags &= ~REQ_F_ARM_LTIMEOUT;
+-		if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
+-			io_remove_next_linked(req);
+-			io_fill_cqe_req(link, -ECANCELED, 0);
+-			io_put_req_deferred(link);
+-			posted = true;
+-		}
+-	} else if (req->flags & REQ_F_LINK_TIMEOUT) {
+-		struct io_ring_ctx *ctx = req->ctx;
+-
+-		spin_lock_irq(&ctx->timeout_lock);
+-		posted = io_kill_linked_timeout(req);
+-		spin_unlock_irq(&ctx->timeout_lock);
+-	}
+-	if (unlikely((req->flags & REQ_F_FAIL) &&
+-		     !(req->flags & REQ_F_HARDLINK))) {
+-		posted |= (req->link != NULL);
+-		io_fail_links(req);
+-	}
+-	return posted;
+-}
+-
+-static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
+-{
+-	struct io_kiocb *nxt;
+-
+-	/*
+-	 * If LINK is set, we have dependent requests in this chain. If we
+-	 * didn't fail this request, queue the first one up, moving any other
+-	 * dependencies to the next request. In case of failure, fail the rest
+-	 * of the chain.
+-	 */
+-	if (req->flags & IO_DISARM_MASK) {
+-		struct io_ring_ctx *ctx = req->ctx;
+-		bool posted;
+-
+-		spin_lock(&ctx->completion_lock);
+-		posted = io_disarm_next(req);
+-		if (posted)
+-			io_commit_cqring(req->ctx);
+-		spin_unlock(&ctx->completion_lock);
+-		if (posted)
+-			io_cqring_ev_posted(ctx);
+-	}
+-	nxt = req->link;
+-	req->link = NULL;
+-	return nxt;
+-}
+-
+-static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
+-{
+-	if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK))))
+-		return NULL;
+-	return __io_req_find_next(req);
+-}
+-
+-static void ctx_flush_and_put(struct io_ring_ctx *ctx, bool *locked)
+-{
+-	if (!ctx)
+-		return;
+-	if (*locked) {
+-		if (ctx->submit_state.compl_nr)
+-			io_submit_flush_completions(ctx);
+-		mutex_unlock(&ctx->uring_lock);
+-		*locked = false;
+-	}
+-	percpu_ref_put(&ctx->refs);
+-}
+-
+-static void tctx_task_work(struct callback_head *cb)
+-{
+-	bool locked = false;
+-	struct io_ring_ctx *ctx = NULL;
+-	struct io_uring_task *tctx = container_of(cb, struct io_uring_task,
+-						  task_work);
+-
+-	while (1) {
+-		struct io_wq_work_node *node;
+-
+-		if (!tctx->task_list.first && locked && ctx->submit_state.compl_nr)
+-			io_submit_flush_completions(ctx);
+-
+-		spin_lock_irq(&tctx->task_lock);
+-		node = tctx->task_list.first;
+-		INIT_WQ_LIST(&tctx->task_list);
+-		if (!node)
+-			tctx->task_running = false;
+-		spin_unlock_irq(&tctx->task_lock);
+-		if (!node)
+-			break;
+-
+-		do {
+-			struct io_wq_work_node *next = node->next;
+-			struct io_kiocb *req = container_of(node, struct io_kiocb,
+-							    io_task_work.node);
+-
+-			if (req->ctx != ctx) {
+-				ctx_flush_and_put(ctx, &locked);
+-				ctx = req->ctx;
+-				/* if not contended, grab and improve batching */
+-				locked = mutex_trylock(&ctx->uring_lock);
+-				percpu_ref_get(&ctx->refs);
+-			}
+-			req->io_task_work.func(req, &locked);
+-			node = next;
+-		} while (node);
+-
+-		cond_resched();
+-	}
+-
+-	ctx_flush_and_put(ctx, &locked);
+-
+-	/* relaxed read is enough as only the task itself sets ->in_idle */
+-	if (unlikely(atomic_read(&tctx->in_idle)))
+-		io_uring_drop_tctx_refs(current);
+-}
+-
+-static void io_req_task_work_add(struct io_kiocb *req)
+-{
+-	struct task_struct *tsk = req->task;
+-	struct io_uring_task *tctx = tsk->io_uring;
+-	enum task_work_notify_mode notify;
+-	struct io_wq_work_node *node;
+-	unsigned long flags;
+-	bool running;
+-
+-	WARN_ON_ONCE(!tctx);
+-
+-	spin_lock_irqsave(&tctx->task_lock, flags);
+-	wq_list_add_tail(&req->io_task_work.node, &tctx->task_list);
+-	running = tctx->task_running;
+-	if (!running)
+-		tctx->task_running = true;
+-	spin_unlock_irqrestore(&tctx->task_lock, flags);
+-
+-	/* task_work already pending, we're done */
+-	if (running)
+-		return;
+-
+-	/*
+-	 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
+-	 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
+-	 * processing task_work. There's no reliable way to tell if TWA_RESUME
+-	 * will do the job.
+-	 */
+-	notify = (req->ctx->flags & IORING_SETUP_SQPOLL) ? TWA_NONE : TWA_SIGNAL;
+-	if (!task_work_add(tsk, &tctx->task_work, notify)) {
+-		wake_up_process(tsk);
+-		return;
+-	}
+-
+-	spin_lock_irqsave(&tctx->task_lock, flags);
+-	tctx->task_running = false;
+-	node = tctx->task_list.first;
+-	INIT_WQ_LIST(&tctx->task_list);
+-	spin_unlock_irqrestore(&tctx->task_lock, flags);
+-
+-	while (node) {
+-		req = container_of(node, struct io_kiocb, io_task_work.node);
+-		node = node->next;
+-		if (llist_add(&req->io_task_work.fallback_node,
+-			      &req->ctx->fallback_llist))
+-			schedule_delayed_work(&req->ctx->fallback_work, 1);
+-	}
+-}
+-
+-static void io_req_task_cancel(struct io_kiocb *req, bool *locked)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	/* not needed for normal modes, but SQPOLL depends on it */
+-	io_tw_lock(ctx, locked);
+-	io_req_complete_failed(req, req->result);
+-}
+-
+-static void io_req_task_submit(struct io_kiocb *req, bool *locked)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	io_tw_lock(ctx, locked);
+-	/* req->task == current here, checking PF_EXITING is safe */
+-	if (likely(!(req->task->flags & PF_EXITING)))
+-		__io_queue_sqe(req);
+-	else
+-		io_req_complete_failed(req, -EFAULT);
+-}
+-
+-static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
+-{
+-	req->result = ret;
+-	req->io_task_work.func = io_req_task_cancel;
+-	io_req_task_work_add(req);
+-}
+-
+-static void io_req_task_queue(struct io_kiocb *req)
+-{
+-	req->io_task_work.func = io_req_task_submit;
+-	io_req_task_work_add(req);
+-}
+-
+-static void io_req_task_queue_reissue(struct io_kiocb *req)
+-{
+-	req->io_task_work.func = io_queue_async_work;
+-	io_req_task_work_add(req);
+-}
+-
+-static inline void io_queue_next(struct io_kiocb *req)
+-{
+-	struct io_kiocb *nxt = io_req_find_next(req);
+-
+-	if (nxt)
+-		io_req_task_queue(nxt);
+-}
+-
+-static void io_free_req(struct io_kiocb *req)
+-{
+-	io_queue_next(req);
+-	__io_free_req(req);
+-}
+-
+-static void io_free_req_work(struct io_kiocb *req, bool *locked)
+-{
+-	io_free_req(req);
+-}
+-
+-struct req_batch {
+-	struct task_struct	*task;
+-	int			task_refs;
+-	int			ctx_refs;
+-};
+-
+-static inline void io_init_req_batch(struct req_batch *rb)
+-{
+-	rb->task_refs = 0;
+-	rb->ctx_refs = 0;
+-	rb->task = NULL;
+-}
+-
+-static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
+-				     struct req_batch *rb)
+-{
+-	if (rb->ctx_refs)
+-		percpu_ref_put_many(&ctx->refs, rb->ctx_refs);
+-	if (rb->task)
+-		io_put_task(rb->task, rb->task_refs);
+-}
+-
+-static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req,
+-			      struct io_submit_state *state)
+-{
+-	io_queue_next(req);
+-	io_dismantle_req(req);
+-
+-	if (req->task != rb->task) {
+-		if (rb->task)
+-			io_put_task(rb->task, rb->task_refs);
+-		rb->task = req->task;
+-		rb->task_refs = 0;
+-	}
+-	rb->task_refs++;
+-	rb->ctx_refs++;
+-
+-	if (state->free_reqs != ARRAY_SIZE(state->reqs))
+-		state->reqs[state->free_reqs++] = req;
+-	else
+-		list_add(&req->inflight_entry, &state->free_list);
+-}
+-
+-static void io_submit_flush_completions(struct io_ring_ctx *ctx)
+-	__must_hold(&ctx->uring_lock)
+-{
+-	struct io_submit_state *state = &ctx->submit_state;
+-	int i, nr = state->compl_nr;
+-	struct req_batch rb;
+-
+-	spin_lock(&ctx->completion_lock);
+-	for (i = 0; i < nr; i++) {
+-		struct io_kiocb *req = state->compl_reqs[i];
+-
+-		__io_fill_cqe(ctx, req->user_data, req->result,
+-			      req->compl.cflags);
+-	}
+-	io_commit_cqring(ctx);
+-	spin_unlock(&ctx->completion_lock);
+-	io_cqring_ev_posted(ctx);
+-
+-	io_init_req_batch(&rb);
+-	for (i = 0; i < nr; i++) {
+-		struct io_kiocb *req = state->compl_reqs[i];
+-
+-		if (req_ref_put_and_test(req))
+-			io_req_free_batch(&rb, req, &ctx->submit_state);
+-	}
+-
+-	io_req_free_batch_finish(ctx, &rb);
+-	state->compl_nr = 0;
+-}
+-
+-/*
+- * Drop reference to request, return next in chain (if there is one) if this
+- * was the last reference to this request.
+- */
+-static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
+-{
+-	struct io_kiocb *nxt = NULL;
+-
+-	if (req_ref_put_and_test(req)) {
+-		nxt = io_req_find_next(req);
+-		__io_free_req(req);
+-	}
+-	return nxt;
+-}
+-
+-static inline void io_put_req(struct io_kiocb *req)
+-{
+-	if (req_ref_put_and_test(req))
+-		io_free_req(req);
+-}
+-
+-static inline void io_put_req_deferred(struct io_kiocb *req)
+-{
+-	if (req_ref_put_and_test(req)) {
+-		req->io_task_work.func = io_free_req_work;
+-		io_req_task_work_add(req);
+-	}
+-}
+-
+-static unsigned io_cqring_events(struct io_ring_ctx *ctx)
+-{
+-	/* See comment at the top of this file */
+-	smp_rmb();
+-	return __io_cqring_events(ctx);
+-}
+-
+-static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
+-{
+-	struct io_rings *rings = ctx->rings;
+-
+-	/* make sure SQ entry isn't read before tail */
+-	return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
+-}
+-
+-static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
+-{
+-	unsigned int cflags;
+-
+-	cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
+-	cflags |= IORING_CQE_F_BUFFER;
+-	req->flags &= ~REQ_F_BUFFER_SELECTED;
+-	kfree(kbuf);
+-	return cflags;
+-}
+-
+-static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
+-{
+-	struct io_buffer *kbuf;
+-
+-	if (likely(!(req->flags & REQ_F_BUFFER_SELECTED)))
+-		return 0;
+-	kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
+-	return io_put_kbuf(req, kbuf);
+-}
+-
+-static inline bool io_run_task_work(void)
+-{
+-	if (test_thread_flag(TIF_NOTIFY_SIGNAL) || current->task_works) {
+-		__set_current_state(TASK_RUNNING);
+-		tracehook_notify_signal();
+-		return true;
+-	}
+-
+-	return false;
+-}
+-
+-/*
+- * Find and free completed poll iocbs
+- */
+-static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
+-			       struct list_head *done)
+-{
+-	struct req_batch rb;
+-	struct io_kiocb *req;
+-
+-	/* order with ->result store in io_complete_rw_iopoll() */
+-	smp_rmb();
+-
+-	io_init_req_batch(&rb);
+-	while (!list_empty(done)) {
+-		req = list_first_entry(done, struct io_kiocb, inflight_entry);
+-		list_del(&req->inflight_entry);
+-
+-		io_fill_cqe_req(req, req->result, io_put_rw_kbuf(req));
+-		(*nr_events)++;
+-
+-		if (req_ref_put_and_test(req))
+-			io_req_free_batch(&rb, req, &ctx->submit_state);
+-	}
+-
+-	io_commit_cqring(ctx);
+-	io_cqring_ev_posted_iopoll(ctx);
+-	io_req_free_batch_finish(ctx, &rb);
+-}
+-
+-static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
+-			long min)
+-{
+-	struct io_kiocb *req, *tmp;
+-	LIST_HEAD(done);
+-	bool spin;
+-
+-	/*
+-	 * Only spin for completions if we don't have multiple devices hanging
+-	 * off our complete list, and we're under the requested amount.
+-	 */
+-	spin = !ctx->poll_multi_queue && *nr_events < min;
+-
+-	list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
+-		struct kiocb *kiocb = &req->rw.kiocb;
+-		int ret;
+-
+-		/*
+-		 * Move completed and retryable entries to our local lists.
+-		 * If we find a request that requires polling, break out
+-		 * and complete those lists first, if we have entries there.
+-		 */
+-		if (READ_ONCE(req->iopoll_completed)) {
+-			list_move_tail(&req->inflight_entry, &done);
+-			continue;
+-		}
+-		if (!list_empty(&done))
+-			break;
+-
+-		ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin);
+-		if (unlikely(ret < 0))
+-			return ret;
+-		else if (ret)
+-			spin = false;
+-
+-		/* iopoll may have completed current req */
+-		if (READ_ONCE(req->iopoll_completed))
+-			list_move_tail(&req->inflight_entry, &done);
+-	}
+-
+-	if (!list_empty(&done))
+-		io_iopoll_complete(ctx, nr_events, &done);
+-
+-	return 0;
+-}
+-
+-/*
+- * We can't just wait for polled events to come to us, we have to actively
+- * find and complete them.
+- */
+-static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
+-{
+-	if (!(ctx->flags & IORING_SETUP_IOPOLL))
+-		return;
+-
+-	mutex_lock(&ctx->uring_lock);
+-	while (!list_empty(&ctx->iopoll_list)) {
+-		unsigned int nr_events = 0;
+-
+-		io_do_iopoll(ctx, &nr_events, 0);
+-
+-		/* let it sleep and repeat later if can't complete a request */
+-		if (nr_events == 0)
+-			break;
+-		/*
+-		 * Ensure we allow local-to-the-cpu processing to take place,
+-		 * in this case we need to ensure that we reap all events.
+-		 * Also let task_work, etc. to progress by releasing the mutex
+-		 */
+-		if (need_resched()) {
+-			mutex_unlock(&ctx->uring_lock);
+-			cond_resched();
+-			mutex_lock(&ctx->uring_lock);
+-		}
+-	}
+-	mutex_unlock(&ctx->uring_lock);
+-}
+-
+-static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
+-{
+-	unsigned int nr_events = 0;
+-	int ret = 0;
+-
+-	/*
+-	 * We disallow the app entering submit/complete with polling, but we
+-	 * still need to lock the ring to prevent racing with polled issue
+-	 * that got punted to a workqueue.
+-	 */
+-	mutex_lock(&ctx->uring_lock);
+-	/*
+-	 * Don't enter poll loop if we already have events pending.
+-	 * If we do, we can potentially be spinning for commands that
+-	 * already triggered a CQE (eg in error).
+-	 */
+-	if (test_bit(0, &ctx->check_cq_overflow))
+-		__io_cqring_overflow_flush(ctx, false);
+-	if (io_cqring_events(ctx))
+-		goto out;
+-	do {
+-		/*
+-		 * If a submit got punted to a workqueue, we can have the
+-		 * application entering polling for a command before it gets
+-		 * issued. That app will hold the uring_lock for the duration
+-		 * of the poll right here, so we need to take a breather every
+-		 * now and then to ensure that the issue has a chance to add
+-		 * the poll to the issued list. Otherwise we can spin here
+-		 * forever, while the workqueue is stuck trying to acquire the
+-		 * very same mutex.
+-		 */
+-		if (list_empty(&ctx->iopoll_list)) {
+-			u32 tail = ctx->cached_cq_tail;
+-
+-			mutex_unlock(&ctx->uring_lock);
+-			io_run_task_work();
+-			mutex_lock(&ctx->uring_lock);
+-
+-			/* some requests don't go through iopoll_list */
+-			if (tail != ctx->cached_cq_tail ||
+-			    list_empty(&ctx->iopoll_list))
+-				break;
+-		}
+-		ret = io_do_iopoll(ctx, &nr_events, min);
+-	} while (!ret && nr_events < min && !need_resched());
+-out:
+-	mutex_unlock(&ctx->uring_lock);
+-	return ret;
+-}
+-
+-static void kiocb_end_write(struct io_kiocb *req)
+-{
+-	/*
+-	 * Tell lockdep we inherited freeze protection from submission
+-	 * thread.
+-	 */
+-	if (req->flags & REQ_F_ISREG) {
+-		struct super_block *sb = file_inode(req->file)->i_sb;
+-
+-		__sb_writers_acquired(sb, SB_FREEZE_WRITE);
+-		sb_end_write(sb);
+-	}
+-}
+-
+-#ifdef CONFIG_BLOCK
+-static bool io_resubmit_prep(struct io_kiocb *req)
+-{
+-	struct io_async_rw *rw = req->async_data;
+-
+-	if (!rw)
+-		return !io_req_prep_async(req);
+-	iov_iter_restore(&rw->iter, &rw->iter_state);
+-	return true;
+-}
+-
+-static bool io_rw_should_reissue(struct io_kiocb *req)
+-{
+-	umode_t mode = file_inode(req->file)->i_mode;
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	if (!S_ISBLK(mode) && !S_ISREG(mode))
+-		return false;
+-	if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
+-	    !(ctx->flags & IORING_SETUP_IOPOLL)))
+-		return false;
+-	/*
+-	 * If ref is dying, we might be running poll reap from the exit work.
+-	 * Don't attempt to reissue from that path, just let it fail with
+-	 * -EAGAIN.
+-	 */
+-	if (percpu_ref_is_dying(&ctx->refs))
+-		return false;
+-	/*
+-	 * Play it safe and assume not safe to re-import and reissue if we're
+-	 * not in the original thread group (or in task context).
+-	 */
+-	if (!same_thread_group(req->task, current) || !in_task())
+-		return false;
+-	return true;
+-}
+-#else
+-static bool io_resubmit_prep(struct io_kiocb *req)
+-{
+-	return false;
+-}
+-static bool io_rw_should_reissue(struct io_kiocb *req)
+-{
+-	return false;
+-}
+-#endif
+-
+-static bool __io_complete_rw_common(struct io_kiocb *req, long res)
+-{
+-	if (req->rw.kiocb.ki_flags & IOCB_WRITE) {
+-		kiocb_end_write(req);
+-		fsnotify_modify(req->file);
+-	} else {
+-		fsnotify_access(req->file);
+-	}
+-	if (res != req->result) {
+-		if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
+-		    io_rw_should_reissue(req)) {
+-			req->flags |= REQ_F_REISSUE;
+-			return true;
+-		}
+-		req_set_fail(req);
+-		req->result = res;
+-	}
+-	return false;
+-}
+-
+-static inline int io_fixup_rw_res(struct io_kiocb *req, unsigned res)
+-{
+-	struct io_async_rw *io = req->async_data;
+-
+-	/* add previously done IO, if any */
+-	if (io && io->bytes_done > 0) {
+-		if (res < 0)
+-			res = io->bytes_done;
+-		else
+-			res += io->bytes_done;
+-	}
+-	return res;
+-}
+-
+-static void io_req_task_complete(struct io_kiocb *req, bool *locked)
+-{
+-	unsigned int cflags = io_put_rw_kbuf(req);
+-	int res = req->result;
+-
+-	if (*locked) {
+-		struct io_ring_ctx *ctx = req->ctx;
+-		struct io_submit_state *state = &ctx->submit_state;
+-
+-		io_req_complete_state(req, res, cflags);
+-		state->compl_reqs[state->compl_nr++] = req;
+-		if (state->compl_nr == ARRAY_SIZE(state->compl_reqs))
+-			io_submit_flush_completions(ctx);
+-	} else {
+-		io_req_complete_post(req, res, cflags);
+-	}
+-}
+-
+-static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
+-			     unsigned int issue_flags)
+-{
+-	if (__io_complete_rw_common(req, res))
+-		return;
+-	__io_req_complete(req, issue_flags, io_fixup_rw_res(req, res), io_put_rw_kbuf(req));
+-}
+-
+-static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
+-{
+-	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
+-
+-	if (__io_complete_rw_common(req, res))
+-		return;
+-	req->result = io_fixup_rw_res(req, res);
+-	req->io_task_work.func = io_req_task_complete;
+-	io_req_task_work_add(req);
+-}
+-
+-static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
+-{
+-	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
+-
+-	if (kiocb->ki_flags & IOCB_WRITE)
+-		kiocb_end_write(req);
+-	if (unlikely(res != req->result)) {
+-		if (res == -EAGAIN && io_rw_should_reissue(req)) {
+-			req->flags |= REQ_F_REISSUE;
+-			return;
+-		}
+-	}
+-
+-	WRITE_ONCE(req->result, res);
+-	/* order with io_iopoll_complete() checking ->result */
+-	smp_wmb();
+-	WRITE_ONCE(req->iopoll_completed, 1);
+-}
+-
+-/*
+- * After the iocb has been issued, it's safe to be found on the poll list.
+- * Adding the kiocb to the list AFTER submission ensures that we don't
+- * find it from a io_do_iopoll() thread before the issuer is done
+- * accessing the kiocb cookie.
+- */
+-static void io_iopoll_req_issued(struct io_kiocb *req)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	const bool in_async = io_wq_current_is_worker();
+-
+-	/* workqueue context doesn't hold uring_lock, grab it now */
+-	if (unlikely(in_async))
+-		mutex_lock(&ctx->uring_lock);
+-
+-	/*
+-	 * Track whether we have multiple files in our lists. This will impact
+-	 * how we do polling eventually, not spinning if we're on potentially
+-	 * different devices.
+-	 */
+-	if (list_empty(&ctx->iopoll_list)) {
+-		ctx->poll_multi_queue = false;
+-	} else if (!ctx->poll_multi_queue) {
+-		struct io_kiocb *list_req;
+-		unsigned int queue_num0, queue_num1;
+-
+-		list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
+-						inflight_entry);
+-
+-		if (list_req->file != req->file) {
+-			ctx->poll_multi_queue = true;
+-		} else {
+-			queue_num0 = blk_qc_t_to_queue_num(list_req->rw.kiocb.ki_cookie);
+-			queue_num1 = blk_qc_t_to_queue_num(req->rw.kiocb.ki_cookie);
+-			if (queue_num0 != queue_num1)
+-				ctx->poll_multi_queue = true;
+-		}
+-	}
+-
+-	/*
+-	 * For fast devices, IO may have already completed. If it has, add
+-	 * it to the front so we find it first.
+-	 */
+-	if (READ_ONCE(req->iopoll_completed))
+-		list_add(&req->inflight_entry, &ctx->iopoll_list);
+-	else
+-		list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
+-
+-	if (unlikely(in_async)) {
+-		/*
+-		 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
+-		 * in sq thread task context or in io worker task context. If
+-		 * current task context is sq thread, we don't need to check
+-		 * whether should wake up sq thread.
+-		 */
+-		if ((ctx->flags & IORING_SETUP_SQPOLL) &&
+-		    wq_has_sleeper(&ctx->sq_data->wait))
+-			wake_up(&ctx->sq_data->wait);
+-
+-		mutex_unlock(&ctx->uring_lock);
+-	}
+-}
+-
+-static bool io_bdev_nowait(struct block_device *bdev)
+-{
+-	return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
+-}
+-
+-/*
+- * If we tracked the file through the SCM inflight mechanism, we could support
+- * any file. For now, just ensure that anything potentially problematic is done
+- * inline.
+- */
+-static bool __io_file_supports_nowait(struct file *file, int rw)
+-{
+-	umode_t mode = file_inode(file)->i_mode;
+-
+-	if (S_ISBLK(mode)) {
+-		if (IS_ENABLED(CONFIG_BLOCK) &&
+-		    io_bdev_nowait(I_BDEV(file->f_mapping->host)))
+-			return true;
+-		return false;
+-	}
+-	if (S_ISSOCK(mode))
+-		return true;
+-	if (S_ISREG(mode)) {
+-		if (IS_ENABLED(CONFIG_BLOCK) &&
+-		    io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
+-		    file->f_op != &io_uring_fops)
+-			return true;
+-		return false;
+-	}
+-
+-	/* any ->read/write should understand O_NONBLOCK */
+-	if (file->f_flags & O_NONBLOCK)
+-		return true;
+-
+-	if (!(file->f_mode & FMODE_NOWAIT))
+-		return false;
+-
+-	if (rw == READ)
+-		return file->f_op->read_iter != NULL;
+-
+-	return file->f_op->write_iter != NULL;
+-}
+-
+-static bool io_file_supports_nowait(struct io_kiocb *req, int rw)
+-{
+-	if (rw == READ && (req->flags & REQ_F_NOWAIT_READ))
+-		return true;
+-	else if (rw == WRITE && (req->flags & REQ_F_NOWAIT_WRITE))
+-		return true;
+-
+-	return __io_file_supports_nowait(req->file, rw);
+-}
+-
+-static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+-		      int rw)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct kiocb *kiocb = &req->rw.kiocb;
+-	struct file *file = req->file;
+-	unsigned ioprio;
+-	int ret;
+-
+-	if (!io_req_ffs_set(req) && S_ISREG(file_inode(file)->i_mode))
+-		req->flags |= REQ_F_ISREG;
+-
+-	kiocb->ki_pos = READ_ONCE(sqe->off);
+-	if (kiocb->ki_pos == -1) {
+-		if (!(file->f_mode & FMODE_STREAM)) {
+-			req->flags |= REQ_F_CUR_POS;
+-			kiocb->ki_pos = file->f_pos;
+-		} else {
+-			kiocb->ki_pos = 0;
+-		}
+-	}
+-	kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
+-	kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
+-	ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
+-	if (unlikely(ret))
+-		return ret;
+-
+-	/*
+-	 * If the file is marked O_NONBLOCK, still allow retry for it if it
+-	 * supports async. Otherwise it's impossible to use O_NONBLOCK files
+-	 * reliably. If not, or it IOCB_NOWAIT is set, don't retry.
+-	 */
+-	if ((kiocb->ki_flags & IOCB_NOWAIT) ||
+-	    ((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req, rw)))
+-		req->flags |= REQ_F_NOWAIT;
+-
+-	ioprio = READ_ONCE(sqe->ioprio);
+-	if (ioprio) {
+-		ret = ioprio_check_cap(ioprio);
+-		if (ret)
+-			return ret;
+-
+-		kiocb->ki_ioprio = ioprio;
+-	} else
+-		kiocb->ki_ioprio = get_current_ioprio();
+-
+-	if (ctx->flags & IORING_SETUP_IOPOLL) {
+-		if (!(kiocb->ki_flags & IOCB_DIRECT) ||
+-		    !kiocb->ki_filp->f_op->iopoll)
+-			return -EOPNOTSUPP;
+-
+-		kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE;
+-		kiocb->ki_complete = io_complete_rw_iopoll;
+-		req->iopoll_completed = 0;
+-	} else {
+-		if (kiocb->ki_flags & IOCB_HIPRI)
+-			return -EINVAL;
+-		kiocb->ki_complete = io_complete_rw;
+-	}
+-
+-	/* used for fixed read/write too - just read unconditionally */
+-	req->buf_index = READ_ONCE(sqe->buf_index);
+-	req->imu = NULL;
+-
+-	if (req->opcode == IORING_OP_READ_FIXED ||
+-	    req->opcode == IORING_OP_WRITE_FIXED) {
+-		struct io_ring_ctx *ctx = req->ctx;
+-		u16 index;
+-
+-		if (unlikely(req->buf_index >= ctx->nr_user_bufs))
+-			return -EFAULT;
+-		index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
+-		req->imu = ctx->user_bufs[index];
+-		io_req_set_rsrc_node(req);
+-	}
+-
+-	req->rw.addr = READ_ONCE(sqe->addr);
+-	req->rw.len = READ_ONCE(sqe->len);
+-	return 0;
+-}
+-
+-static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
+-{
+-	switch (ret) {
+-	case -EIOCBQUEUED:
+-		break;
+-	case -ERESTARTSYS:
+-	case -ERESTARTNOINTR:
+-	case -ERESTARTNOHAND:
+-	case -ERESTART_RESTARTBLOCK:
+-		/*
+-		 * We can't just restart the syscall, since previously
+-		 * submitted sqes may already be in progress. Just fail this
+-		 * IO with EINTR.
+-		 */
+-		ret = -EINTR;
+-		fallthrough;
+-	default:
+-		kiocb->ki_complete(kiocb, ret, 0);
+-	}
+-}
+-
+-static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
+-		       unsigned int issue_flags)
+-{
+-	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
+-
+-	if (req->flags & REQ_F_CUR_POS)
+-		req->file->f_pos = kiocb->ki_pos;
+-	if (ret >= 0 && (kiocb->ki_complete == io_complete_rw))
+-		__io_complete_rw(req, ret, 0, issue_flags);
+-	else
+-		io_rw_done(kiocb, ret);
+-
+-	if (req->flags & REQ_F_REISSUE) {
+-		req->flags &= ~REQ_F_REISSUE;
+-		if (io_resubmit_prep(req)) {
+-			io_req_task_queue_reissue(req);
+-		} else {
+-			unsigned int cflags = io_put_rw_kbuf(req);
+-			struct io_ring_ctx *ctx = req->ctx;
+-
+-			ret = io_fixup_rw_res(req, ret);
+-			req_set_fail(req);
+-			if (!(issue_flags & IO_URING_F_NONBLOCK)) {
+-				mutex_lock(&ctx->uring_lock);
+-				__io_req_complete(req, issue_flags, ret, cflags);
+-				mutex_unlock(&ctx->uring_lock);
+-			} else {
+-				__io_req_complete(req, issue_flags, ret, cflags);
+-			}
+-		}
+-	}
+-}
+-
+-static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
+-			     struct io_mapped_ubuf *imu)
+-{
+-	size_t len = req->rw.len;
+-	u64 buf_end, buf_addr = req->rw.addr;
+-	size_t offset;
+-
+-	if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
+-		return -EFAULT;
+-	/* not inside the mapped region */
+-	if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
+-		return -EFAULT;
+-
+-	/*
+-	 * May not be a start of buffer, set size appropriately
+-	 * and advance us to the beginning.
+-	 */
+-	offset = buf_addr - imu->ubuf;
+-	iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
+-
+-	if (offset) {
+-		/*
+-		 * Don't use iov_iter_advance() here, as it's really slow for
+-		 * using the latter parts of a big fixed buffer - it iterates
+-		 * over each segment manually. We can cheat a bit here, because
+-		 * we know that:
+-		 *
+-		 * 1) it's a BVEC iter, we set it up
+-		 * 2) all bvecs are PAGE_SIZE in size, except potentially the
+-		 *    first and last bvec
+-		 *
+-		 * So just find our index, and adjust the iterator afterwards.
+-		 * If the offset is within the first bvec (or the whole first
+-		 * bvec, just use iov_iter_advance(). This makes it easier
+-		 * since we can just skip the first segment, which may not
+-		 * be PAGE_SIZE aligned.
+-		 */
+-		const struct bio_vec *bvec = imu->bvec;
+-
+-		if (offset <= bvec->bv_len) {
+-			iov_iter_advance(iter, offset);
+-		} else {
+-			unsigned long seg_skip;
+-
+-			/* skip first vec */
+-			offset -= bvec->bv_len;
+-			seg_skip = 1 + (offset >> PAGE_SHIFT);
+-
+-			iter->bvec = bvec + seg_skip;
+-			iter->nr_segs -= seg_skip;
+-			iter->count -= bvec->bv_len + offset;
+-			iter->iov_offset = offset & ~PAGE_MASK;
+-		}
+-	}
+-
+-	return 0;
+-}
+-
+-static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
+-{
+-	if (WARN_ON_ONCE(!req->imu))
+-		return -EFAULT;
+-	return __io_import_fixed(req, rw, iter, req->imu);
+-}
+-
+-static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
+-{
+-	if (needs_lock)
+-		mutex_unlock(&ctx->uring_lock);
+-}
+-
+-static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
+-{
+-	/*
+-	 * "Normal" inline submissions always hold the uring_lock, since we
+-	 * grab it from the system call. Same is true for the SQPOLL offload.
+-	 * The only exception is when we've detached the request and issue it
+-	 * from an async worker thread, grab the lock for that case.
+-	 */
+-	if (needs_lock)
+-		mutex_lock(&ctx->uring_lock);
+-}
+-
+-static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
+-					  int bgid, struct io_buffer *kbuf,
+-					  bool needs_lock)
+-{
+-	struct io_buffer *head;
+-
+-	if (req->flags & REQ_F_BUFFER_SELECTED)
+-		return kbuf;
+-
+-	io_ring_submit_lock(req->ctx, needs_lock);
+-
+-	lockdep_assert_held(&req->ctx->uring_lock);
+-
+-	head = xa_load(&req->ctx->io_buffers, bgid);
+-	if (head) {
+-		if (!list_empty(&head->list)) {
+-			kbuf = list_last_entry(&head->list, struct io_buffer,
+-							list);
+-			list_del(&kbuf->list);
+-		} else {
+-			kbuf = head;
+-			xa_erase(&req->ctx->io_buffers, bgid);
+-		}
+-		if (*len > kbuf->len)
+-			*len = kbuf->len;
+-	} else {
+-		kbuf = ERR_PTR(-ENOBUFS);
+-	}
+-
+-	io_ring_submit_unlock(req->ctx, needs_lock);
+-
+-	return kbuf;
+-}
+-
+-static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
+-					bool needs_lock)
+-{
+-	struct io_buffer *kbuf;
+-	u16 bgid;
+-
+-	kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
+-	bgid = req->buf_index;
+-	kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
+-	if (IS_ERR(kbuf))
+-		return kbuf;
+-	req->rw.addr = (u64) (unsigned long) kbuf;
+-	req->flags |= REQ_F_BUFFER_SELECTED;
+-	return u64_to_user_ptr(kbuf->addr);
+-}
+-
+-#ifdef CONFIG_COMPAT
+-static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
+-				bool needs_lock)
+-{
+-	struct compat_iovec __user *uiov;
+-	compat_ssize_t clen;
+-	void __user *buf;
+-	ssize_t len;
+-
+-	uiov = u64_to_user_ptr(req->rw.addr);
+-	if (!access_ok(uiov, sizeof(*uiov)))
+-		return -EFAULT;
+-	if (__get_user(clen, &uiov->iov_len))
+-		return -EFAULT;
+-	if (clen < 0)
+-		return -EINVAL;
+-
+-	len = clen;
+-	buf = io_rw_buffer_select(req, &len, needs_lock);
+-	if (IS_ERR(buf))
+-		return PTR_ERR(buf);
+-	iov[0].iov_base = buf;
+-	iov[0].iov_len = (compat_size_t) len;
+-	return 0;
+-}
+-#endif
+-
+-static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
+-				      bool needs_lock)
+-{
+-	struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
+-	void __user *buf;
+-	ssize_t len;
+-
+-	if (copy_from_user(iov, uiov, sizeof(*uiov)))
+-		return -EFAULT;
+-
+-	len = iov[0].iov_len;
+-	if (len < 0)
+-		return -EINVAL;
+-	buf = io_rw_buffer_select(req, &len, needs_lock);
+-	if (IS_ERR(buf))
+-		return PTR_ERR(buf);
+-	iov[0].iov_base = buf;
+-	iov[0].iov_len = len;
+-	return 0;
+-}
+-
+-static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
+-				    bool needs_lock)
+-{
+-	if (req->flags & REQ_F_BUFFER_SELECTED) {
+-		struct io_buffer *kbuf;
+-
+-		kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
+-		iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
+-		iov[0].iov_len = kbuf->len;
+-		return 0;
+-	}
+-	if (req->rw.len != 1)
+-		return -EINVAL;
+-
+-#ifdef CONFIG_COMPAT
+-	if (req->ctx->compat)
+-		return io_compat_import(req, iov, needs_lock);
+-#endif
+-
+-	return __io_iov_buffer_select(req, iov, needs_lock);
+-}
+-
+-static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
+-			   struct iov_iter *iter, bool needs_lock)
+-{
+-	void __user *buf = u64_to_user_ptr(req->rw.addr);
+-	size_t sqe_len = req->rw.len;
+-	u8 opcode = req->opcode;
+-	ssize_t ret;
+-
+-	if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
+-		*iovec = NULL;
+-		return io_import_fixed(req, rw, iter);
+-	}
+-
+-	/* buffer index only valid with fixed read/write, or buffer select  */
+-	if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
+-		return -EINVAL;
+-
+-	if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
+-		if (req->flags & REQ_F_BUFFER_SELECT) {
+-			buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
+-			if (IS_ERR(buf))
+-				return PTR_ERR(buf);
+-			req->rw.len = sqe_len;
+-		}
+-
+-		ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
+-		*iovec = NULL;
+-		return ret;
+-	}
+-
+-	if (req->flags & REQ_F_BUFFER_SELECT) {
+-		ret = io_iov_buffer_select(req, *iovec, needs_lock);
+-		if (!ret)
+-			iov_iter_init(iter, rw, *iovec, 1, (*iovec)->iov_len);
+-		*iovec = NULL;
+-		return ret;
+-	}
+-
+-	return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
+-			      req->ctx->compat);
+-}
+-
+-static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
+-{
+-	return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
+-}
+-
+-/*
+- * For files that don't have ->read_iter() and ->write_iter(), handle them
+- * by looping over ->read() or ->write() manually.
+- */
+-static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
+-{
+-	struct kiocb *kiocb = &req->rw.kiocb;
+-	struct file *file = req->file;
+-	ssize_t ret = 0;
+-
+-	/*
+-	 * Don't support polled IO through this interface, and we can't
+-	 * support non-blocking either. For the latter, this just causes
+-	 * the kiocb to be handled from an async context.
+-	 */
+-	if (kiocb->ki_flags & IOCB_HIPRI)
+-		return -EOPNOTSUPP;
+-	if (kiocb->ki_flags & IOCB_NOWAIT)
+-		return -EAGAIN;
+-
+-	while (iov_iter_count(iter)) {
+-		struct iovec iovec;
+-		ssize_t nr;
+-
+-		if (!iov_iter_is_bvec(iter)) {
+-			iovec = iov_iter_iovec(iter);
+-		} else {
+-			iovec.iov_base = u64_to_user_ptr(req->rw.addr);
+-			iovec.iov_len = req->rw.len;
+-		}
+-
+-		if (rw == READ) {
+-			nr = file->f_op->read(file, iovec.iov_base,
+-					      iovec.iov_len, io_kiocb_ppos(kiocb));
+-		} else {
+-			nr = file->f_op->write(file, iovec.iov_base,
+-					       iovec.iov_len, io_kiocb_ppos(kiocb));
+-		}
+-
+-		if (nr < 0) {
+-			if (!ret)
+-				ret = nr;
+-			break;
+-		}
+-		ret += nr;
+-		if (!iov_iter_is_bvec(iter)) {
+-			iov_iter_advance(iter, nr);
+-		} else {
+-			req->rw.addr += nr;
+-			req->rw.len -= nr;
+-			if (!req->rw.len)
+-				break;
+-		}
+-		if (nr != iovec.iov_len)
+-			break;
+-	}
+-
+-	return ret;
+-}
+-
+-static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
+-			  const struct iovec *fast_iov, struct iov_iter *iter)
+-{
+-	struct io_async_rw *rw = req->async_data;
+-
+-	memcpy(&rw->iter, iter, sizeof(*iter));
+-	rw->free_iovec = iovec;
+-	rw->bytes_done = 0;
+-	/* can only be fixed buffers, no need to do anything */
+-	if (iov_iter_is_bvec(iter))
+-		return;
+-	if (!iovec) {
+-		unsigned iov_off = 0;
+-
+-		rw->iter.iov = rw->fast_iov;
+-		if (iter->iov != fast_iov) {
+-			iov_off = iter->iov - fast_iov;
+-			rw->iter.iov += iov_off;
+-		}
+-		if (rw->fast_iov != fast_iov)
+-			memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
+-			       sizeof(struct iovec) * iter->nr_segs);
+-	} else {
+-		req->flags |= REQ_F_NEED_CLEANUP;
+-	}
+-}
+-
+-static inline int io_alloc_async_data(struct io_kiocb *req)
+-{
+-	WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
+-	req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
+-	return req->async_data == NULL;
+-}
+-
+-static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
+-			     const struct iovec *fast_iov,
+-			     struct iov_iter *iter, bool force)
+-{
+-	if (!force && !io_op_defs[req->opcode].needs_async_setup)
+-		return 0;
+-	if (!req->async_data) {
+-		struct io_async_rw *iorw;
+-
+-		if (io_alloc_async_data(req)) {
+-			kfree(iovec);
+-			return -ENOMEM;
+-		}
+-
+-		io_req_map_rw(req, iovec, fast_iov, iter);
+-		iorw = req->async_data;
+-		/* we've copied and mapped the iter, ensure state is saved */
+-		iov_iter_save_state(&iorw->iter, &iorw->iter_state);
+-	}
+-	return 0;
+-}
+-
+-static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
+-{
+-	struct io_async_rw *iorw = req->async_data;
+-	struct iovec *iov = iorw->fast_iov;
+-	int ret;
+-
+-	ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
+-	if (unlikely(ret < 0))
+-		return ret;
+-
+-	iorw->bytes_done = 0;
+-	iorw->free_iovec = iov;
+-	if (iov)
+-		req->flags |= REQ_F_NEED_CLEANUP;
+-	iov_iter_save_state(&iorw->iter, &iorw->iter_state);
+-	return 0;
+-}
+-
+-static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	if (unlikely(!(req->file->f_mode & FMODE_READ)))
+-		return -EBADF;
+-	return io_prep_rw(req, sqe, READ);
+-}
+-
+-/*
+- * This is our waitqueue callback handler, registered through lock_page_async()
+- * when we initially tried to do the IO with the iocb armed our waitqueue.
+- * This gets called when the page is unlocked, and we generally expect that to
+- * happen when the page IO is completed and the page is now uptodate. This will
+- * queue a task_work based retry of the operation, attempting to copy the data
+- * again. If the latter fails because the page was NOT uptodate, then we will
+- * do a thread based blocking retry of the operation. That's the unexpected
+- * slow path.
+- */
+-static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
+-			     int sync, void *arg)
+-{
+-	struct wait_page_queue *wpq;
+-	struct io_kiocb *req = wait->private;
+-	struct wait_page_key *key = arg;
+-
+-	wpq = container_of(wait, struct wait_page_queue, wait);
+-
+-	if (!wake_page_match(wpq, key))
+-		return 0;
+-
+-	req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
+-	list_del_init(&wait->entry);
+-	io_req_task_queue(req);
+-	return 1;
+-}
+-
+-/*
+- * This controls whether a given IO request should be armed for async page
+- * based retry. If we return false here, the request is handed to the async
+- * worker threads for retry. If we're doing buffered reads on a regular file,
+- * we prepare a private wait_page_queue entry and retry the operation. This
+- * will either succeed because the page is now uptodate and unlocked, or it
+- * will register a callback when the page is unlocked at IO completion. Through
+- * that callback, io_uring uses task_work to setup a retry of the operation.
+- * That retry will attempt the buffered read again. The retry will generally
+- * succeed, or in rare cases where it fails, we then fall back to using the
+- * async worker threads for a blocking retry.
+- */
+-static bool io_rw_should_retry(struct io_kiocb *req)
+-{
+-	struct io_async_rw *rw = req->async_data;
+-	struct wait_page_queue *wait = &rw->wpq;
+-	struct kiocb *kiocb = &req->rw.kiocb;
+-
+-	/* never retry for NOWAIT, we just complete with -EAGAIN */
+-	if (req->flags & REQ_F_NOWAIT)
+-		return false;
+-
+-	/* Only for buffered IO */
+-	if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
+-		return false;
+-
+-	/*
+-	 * just use poll if we can, and don't attempt if the fs doesn't
+-	 * support callback based unlocks
+-	 */
+-	if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
+-		return false;
+-
+-	wait->wait.func = io_async_buf_func;
+-	wait->wait.private = req;
+-	wait->wait.flags = 0;
+-	INIT_LIST_HEAD(&wait->wait.entry);
+-	kiocb->ki_flags |= IOCB_WAITQ;
+-	kiocb->ki_flags &= ~IOCB_NOWAIT;
+-	kiocb->ki_waitq = wait;
+-	return true;
+-}
+-
+-static inline int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
+-{
+-	if (req->file->f_op->read_iter)
+-		return call_read_iter(req->file, &req->rw.kiocb, iter);
+-	else if (req->file->f_op->read)
+-		return loop_rw_iter(READ, req, iter);
+-	else
+-		return -EINVAL;
+-}
+-
+-static bool need_read_all(struct io_kiocb *req)
+-{
+-	return req->flags & REQ_F_ISREG ||
+-		S_ISBLK(file_inode(req->file)->i_mode);
+-}
+-
+-static int io_read(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
+-	struct kiocb *kiocb = &req->rw.kiocb;
+-	struct iov_iter __iter, *iter = &__iter;
+-	struct io_async_rw *rw = req->async_data;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-	struct iov_iter_state __state, *state;
+-	ssize_t ret, ret2;
+-
+-	if (rw) {
+-		iter = &rw->iter;
+-		state = &rw->iter_state;
+-		/*
+-		 * We come here from an earlier attempt, restore our state to
+-		 * match in case it doesn't. It's cheap enough that we don't
+-		 * need to make this conditional.
+-		 */
+-		iov_iter_restore(iter, state);
+-		iovec = NULL;
+-	} else {
+-		ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
+-		if (ret < 0)
+-			return ret;
+-		state = &__state;
+-		iov_iter_save_state(iter, state);
+-	}
+-	req->result = iov_iter_count(iter);
+-
+-	/* Ensure we clear previously set non-block flag */
+-	if (!force_nonblock)
+-		kiocb->ki_flags &= ~IOCB_NOWAIT;
+-	else
+-		kiocb->ki_flags |= IOCB_NOWAIT;
+-
+-	/* If the file doesn't support async, just async punt */
+-	if (force_nonblock && !io_file_supports_nowait(req, READ)) {
+-		ret = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
+-		return ret ?: -EAGAIN;
+-	}
+-
+-	ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), req->result);
+-	if (unlikely(ret)) {
+-		kfree(iovec);
+-		return ret;
+-	}
+-
+-	ret = io_iter_do_read(req, iter);
+-
+-	if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
+-		req->flags &= ~REQ_F_REISSUE;
+-		/* IOPOLL retry should happen for io-wq threads */
+-		if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
+-			goto done;
+-		/* no retry on NONBLOCK nor RWF_NOWAIT */
+-		if (req->flags & REQ_F_NOWAIT)
+-			goto done;
+-		ret = 0;
+-	} else if (ret == -EIOCBQUEUED) {
+-		goto out_free;
+-	} else if (ret <= 0 || ret == req->result || !force_nonblock ||
+-		   (req->flags & REQ_F_NOWAIT) || !need_read_all(req)) {
+-		/* read all, failed, already did sync or don't want to retry */
+-		goto done;
+-	}
+-
+-	/*
+-	 * Don't depend on the iter state matching what was consumed, or being
+-	 * untouched in case of error. Restore it and we'll advance it
+-	 * manually if we need to.
+-	 */
+-	iov_iter_restore(iter, state);
+-
+-	ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
+-	if (ret2)
+-		return ret2;
+-
+-	iovec = NULL;
+-	rw = req->async_data;
+-	/*
+-	 * Now use our persistent iterator and state, if we aren't already.
+-	 * We've restored and mapped the iter to match.
+-	 */
+-	if (iter != &rw->iter) {
+-		iter = &rw->iter;
+-		state = &rw->iter_state;
+-	}
+-
+-	do {
+-		/*
+-		 * We end up here because of a partial read, either from
+-		 * above or inside this loop. Advance the iter by the bytes
+-		 * that were consumed.
+-		 */
+-		iov_iter_advance(iter, ret);
+-		if (!iov_iter_count(iter))
+-			break;
+-		rw->bytes_done += ret;
+-		iov_iter_save_state(iter, state);
+-
+-		/* if we can retry, do so with the callbacks armed */
+-		if (!io_rw_should_retry(req)) {
+-			kiocb->ki_flags &= ~IOCB_WAITQ;
+-			return -EAGAIN;
+-		}
+-
+-		req->result = iov_iter_count(iter);
+-		/*
+-		 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
+-		 * we get -EIOCBQUEUED, then we'll get a notification when the
+-		 * desired page gets unlocked. We can also get a partial read
+-		 * here, and if we do, then just retry at the new offset.
+-		 */
+-		ret = io_iter_do_read(req, iter);
+-		if (ret == -EIOCBQUEUED)
+-			return 0;
+-		/* we got some bytes, but not all. retry. */
+-		kiocb->ki_flags &= ~IOCB_WAITQ;
+-		iov_iter_restore(iter, state);
+-	} while (ret > 0);
+-done:
+-	kiocb_done(kiocb, ret, issue_flags);
+-out_free:
+-	/* it's faster to check here then delegate to kfree */
+-	if (iovec)
+-		kfree(iovec);
+-	return 0;
+-}
+-
+-static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
+-		return -EBADF;
+-	return io_prep_rw(req, sqe, WRITE);
+-}
+-
+-static int io_write(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
+-	struct kiocb *kiocb = &req->rw.kiocb;
+-	struct iov_iter __iter, *iter = &__iter;
+-	struct io_async_rw *rw = req->async_data;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-	struct iov_iter_state __state, *state;
+-	ssize_t ret, ret2;
+-
+-	if (rw) {
+-		iter = &rw->iter;
+-		state = &rw->iter_state;
+-		iov_iter_restore(iter, state);
+-		iovec = NULL;
+-	} else {
+-		ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
+-		if (ret < 0)
+-			return ret;
+-		state = &__state;
+-		iov_iter_save_state(iter, state);
+-	}
+-	req->result = iov_iter_count(iter);
+-
+-	/* Ensure we clear previously set non-block flag */
+-	if (!force_nonblock)
+-		kiocb->ki_flags &= ~IOCB_NOWAIT;
+-	else
+-		kiocb->ki_flags |= IOCB_NOWAIT;
+-
+-	/* If the file doesn't support async, just async punt */
+-	if (force_nonblock && !io_file_supports_nowait(req, WRITE))
+-		goto copy_iov;
+-
+-	/* file path doesn't support NOWAIT for non-direct_IO */
+-	if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
+-	    (req->flags & REQ_F_ISREG))
+-		goto copy_iov;
+-
+-	ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), req->result);
+-	if (unlikely(ret))
+-		goto out_free;
+-
+-	/*
+-	 * Open-code file_start_write here to grab freeze protection,
+-	 * which will be released by another thread in
+-	 * io_complete_rw().  Fool lockdep by telling it the lock got
+-	 * released so that it doesn't complain about the held lock when
+-	 * we return to userspace.
+-	 */
+-	if (req->flags & REQ_F_ISREG) {
+-		sb_start_write(file_inode(req->file)->i_sb);
+-		__sb_writers_release(file_inode(req->file)->i_sb,
+-					SB_FREEZE_WRITE);
+-	}
+-	kiocb->ki_flags |= IOCB_WRITE;
+-
+-	if (req->file->f_op->write_iter)
+-		ret2 = call_write_iter(req->file, kiocb, iter);
+-	else if (req->file->f_op->write)
+-		ret2 = loop_rw_iter(WRITE, req, iter);
+-	else
+-		ret2 = -EINVAL;
+-
+-	if (req->flags & REQ_F_REISSUE) {
+-		req->flags &= ~REQ_F_REISSUE;
+-		ret2 = -EAGAIN;
+-	}
+-
+-	/*
+-	 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
+-	 * retry them without IOCB_NOWAIT.
+-	 */
+-	if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
+-		ret2 = -EAGAIN;
+-	/* no retry on NONBLOCK nor RWF_NOWAIT */
+-	if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
+-		goto done;
+-	if (!force_nonblock || ret2 != -EAGAIN) {
+-		/* IOPOLL retry should happen for io-wq threads */
+-		if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
+-			goto copy_iov;
+-done:
+-		kiocb_done(kiocb, ret2, issue_flags);
+-	} else {
+-copy_iov:
+-		iov_iter_restore(iter, state);
+-		ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
+-		if (!ret) {
+-			if (kiocb->ki_flags & IOCB_WRITE)
+-				kiocb_end_write(req);
+-			return -EAGAIN;
+-		}
+-		return ret;
+-	}
+-out_free:
+-	/* it's reportedly faster than delegating the null check to kfree() */
+-	if (iovec)
+-		kfree(iovec);
+-	return ret;
+-}
+-
+-static int io_renameat_prep(struct io_kiocb *req,
+-			    const struct io_uring_sqe *sqe)
+-{
+-	struct io_rename *ren = &req->rename;
+-	const char __user *oldf, *newf;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->flags & REQ_F_FIXED_FILE))
+-		return -EBADF;
+-
+-	ren->old_dfd = READ_ONCE(sqe->fd);
+-	oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+-	ren->new_dfd = READ_ONCE(sqe->len);
+-	ren->flags = READ_ONCE(sqe->rename_flags);
+-
+-	ren->oldpath = getname(oldf);
+-	if (IS_ERR(ren->oldpath))
+-		return PTR_ERR(ren->oldpath);
+-
+-	ren->newpath = getname(newf);
+-	if (IS_ERR(ren->newpath)) {
+-		putname(ren->oldpath);
+-		return PTR_ERR(ren->newpath);
+-	}
+-
+-	req->flags |= REQ_F_NEED_CLEANUP;
+-	return 0;
+-}
+-
+-static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_rename *ren = &req->rename;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
+-				ren->newpath, ren->flags);
+-
+-	req->flags &= ~REQ_F_NEED_CLEANUP;
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int io_unlinkat_prep(struct io_kiocb *req,
+-			    const struct io_uring_sqe *sqe)
+-{
+-	struct io_unlink *un = &req->unlink;
+-	const char __user *fname;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
+-	    sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->flags & REQ_F_FIXED_FILE))
+-		return -EBADF;
+-
+-	un->dfd = READ_ONCE(sqe->fd);
+-
+-	un->flags = READ_ONCE(sqe->unlink_flags);
+-	if (un->flags & ~AT_REMOVEDIR)
+-		return -EINVAL;
+-
+-	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	un->filename = getname(fname);
+-	if (IS_ERR(un->filename))
+-		return PTR_ERR(un->filename);
+-
+-	req->flags |= REQ_F_NEED_CLEANUP;
+-	return 0;
+-}
+-
+-static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_unlink *un = &req->unlink;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	if (un->flags & AT_REMOVEDIR)
+-		ret = do_rmdir(un->dfd, un->filename);
+-	else
+-		ret = do_unlinkat(un->dfd, un->filename);
+-
+-	req->flags &= ~REQ_F_NEED_CLEANUP;
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int io_mkdirat_prep(struct io_kiocb *req,
+-			    const struct io_uring_sqe *sqe)
+-{
+-	struct io_mkdir *mkd = &req->mkdir;
+-	const char __user *fname;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->off || sqe->rw_flags || sqe->buf_index ||
+-	    sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->flags & REQ_F_FIXED_FILE))
+-		return -EBADF;
+-
+-	mkd->dfd = READ_ONCE(sqe->fd);
+-	mkd->mode = READ_ONCE(sqe->len);
+-
+-	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	mkd->filename = getname(fname);
+-	if (IS_ERR(mkd->filename))
+-		return PTR_ERR(mkd->filename);
+-
+-	req->flags |= REQ_F_NEED_CLEANUP;
+-	return 0;
+-}
+-
+-static int io_mkdirat(struct io_kiocb *req, int issue_flags)
+-{
+-	struct io_mkdir *mkd = &req->mkdir;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	ret = do_mkdirat(mkd->dfd, mkd->filename, mkd->mode);
+-
+-	req->flags &= ~REQ_F_NEED_CLEANUP;
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int io_symlinkat_prep(struct io_kiocb *req,
+-			    const struct io_uring_sqe *sqe)
+-{
+-	struct io_symlink *sl = &req->symlink;
+-	const char __user *oldpath, *newpath;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->len || sqe->rw_flags || sqe->buf_index ||
+-	    sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->flags & REQ_F_FIXED_FILE))
+-		return -EBADF;
+-
+-	sl->new_dfd = READ_ONCE(sqe->fd);
+-	oldpath = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	newpath = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+-
+-	sl->oldpath = getname(oldpath);
+-	if (IS_ERR(sl->oldpath))
+-		return PTR_ERR(sl->oldpath);
+-
+-	sl->newpath = getname(newpath);
+-	if (IS_ERR(sl->newpath)) {
+-		putname(sl->oldpath);
+-		return PTR_ERR(sl->newpath);
+-	}
+-
+-	req->flags |= REQ_F_NEED_CLEANUP;
+-	return 0;
+-}
+-
+-static int io_symlinkat(struct io_kiocb *req, int issue_flags)
+-{
+-	struct io_symlink *sl = &req->symlink;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	ret = do_symlinkat(sl->oldpath, sl->new_dfd, sl->newpath);
+-
+-	req->flags &= ~REQ_F_NEED_CLEANUP;
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int io_linkat_prep(struct io_kiocb *req,
+-			    const struct io_uring_sqe *sqe)
+-{
+-	struct io_hardlink *lnk = &req->hardlink;
+-	const char __user *oldf, *newf;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->flags & REQ_F_FIXED_FILE))
+-		return -EBADF;
+-
+-	lnk->old_dfd = READ_ONCE(sqe->fd);
+-	lnk->new_dfd = READ_ONCE(sqe->len);
+-	oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+-	lnk->flags = READ_ONCE(sqe->hardlink_flags);
+-
+-	lnk->oldpath = getname(oldf);
+-	if (IS_ERR(lnk->oldpath))
+-		return PTR_ERR(lnk->oldpath);
+-
+-	lnk->newpath = getname(newf);
+-	if (IS_ERR(lnk->newpath)) {
+-		putname(lnk->oldpath);
+-		return PTR_ERR(lnk->newpath);
+-	}
+-
+-	req->flags |= REQ_F_NEED_CLEANUP;
+-	return 0;
+-}
+-
+-static int io_linkat(struct io_kiocb *req, int issue_flags)
+-{
+-	struct io_hardlink *lnk = &req->hardlink;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	ret = do_linkat(lnk->old_dfd, lnk->oldpath, lnk->new_dfd,
+-				lnk->newpath, lnk->flags);
+-
+-	req->flags &= ~REQ_F_NEED_CLEANUP;
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int io_shutdown_prep(struct io_kiocb *req,
+-			    const struct io_uring_sqe *sqe)
+-{
+-#if defined(CONFIG_NET)
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (unlikely(sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags ||
+-		     sqe->buf_index || sqe->splice_fd_in))
+-		return -EINVAL;
+-
+-	req->shutdown.how = READ_ONCE(sqe->len);
+-	return 0;
+-#else
+-	return -EOPNOTSUPP;
+-#endif
+-}
+-
+-static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-#if defined(CONFIG_NET)
+-	struct socket *sock;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	sock = sock_from_file(req->file);
+-	if (unlikely(!sock))
+-		return -ENOTSOCK;
+-
+-	ret = __sys_shutdown_sock(sock, req->shutdown.how);
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-#else
+-	return -EOPNOTSUPP;
+-#endif
+-}
+-
+-static int __io_splice_prep(struct io_kiocb *req,
+-			    const struct io_uring_sqe *sqe)
+-{
+-	struct io_splice *sp = &req->splice;
+-	unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-
+-	sp->len = READ_ONCE(sqe->len);
+-	sp->flags = READ_ONCE(sqe->splice_flags);
+-	if (unlikely(sp->flags & ~valid_flags))
+-		return -EINVAL;
+-	sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in);
+-	return 0;
+-}
+-
+-static int io_tee_prep(struct io_kiocb *req,
+-		       const struct io_uring_sqe *sqe)
+-{
+-	if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
+-		return -EINVAL;
+-	return __io_splice_prep(req, sqe);
+-}
+-
+-static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_splice *sp = &req->splice;
+-	struct file *out = sp->file_out;
+-	unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
+-	struct file *in;
+-	long ret = 0;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	in = io_file_get(req->ctx, req, sp->splice_fd_in,
+-				  (sp->flags & SPLICE_F_FD_IN_FIXED));
+-	if (!in) {
+-		ret = -EBADF;
+-		goto done;
+-	}
+-
+-	if (sp->len)
+-		ret = do_tee(in, out, sp->len, flags);
+-
+-	if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
+-		io_put_file(in);
+-done:
+-	if (ret != sp->len)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct io_splice *sp = &req->splice;
+-
+-	sp->off_in = READ_ONCE(sqe->splice_off_in);
+-	sp->off_out = READ_ONCE(sqe->off);
+-	return __io_splice_prep(req, sqe);
+-}
+-
+-static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_splice *sp = &req->splice;
+-	struct file *out = sp->file_out;
+-	unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
+-	loff_t *poff_in, *poff_out;
+-	struct file *in;
+-	long ret = 0;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	in = io_file_get(req->ctx, req, sp->splice_fd_in,
+-				  (sp->flags & SPLICE_F_FD_IN_FIXED));
+-	if (!in) {
+-		ret = -EBADF;
+-		goto done;
+-	}
+-
+-	poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
+-	poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
+-
+-	if (sp->len)
+-		ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
+-
+-	if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
+-		io_put_file(in);
+-done:
+-	if (ret != sp->len)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-/*
+- * IORING_OP_NOP just posts a completion event, nothing else.
+- */
+-static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-
+-	__io_req_complete(req, issue_flags, 0, 0);
+-	return 0;
+-}
+-
+-static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
+-		     sqe->splice_fd_in))
+-		return -EINVAL;
+-
+-	req->sync.flags = READ_ONCE(sqe->fsync_flags);
+-	if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
+-		return -EINVAL;
+-
+-	req->sync.off = READ_ONCE(sqe->off);
+-	req->sync.len = READ_ONCE(sqe->len);
+-	return 0;
+-}
+-
+-static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	loff_t end = req->sync.off + req->sync.len;
+-	int ret;
+-
+-	/* fsync always requires a blocking context */
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	ret = vfs_fsync_range(req->file, req->sync.off,
+-				end > 0 ? end : LLONG_MAX,
+-				req->sync.flags & IORING_FSYNC_DATASYNC);
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int io_fallocate_prep(struct io_kiocb *req,
+-			     const struct io_uring_sqe *sqe)
+-{
+-	if (sqe->ioprio || sqe->buf_index || sqe->rw_flags ||
+-	    sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-
+-	req->sync.off = READ_ONCE(sqe->off);
+-	req->sync.len = READ_ONCE(sqe->addr);
+-	req->sync.mode = READ_ONCE(sqe->len);
+-	return 0;
+-}
+-
+-static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	int ret;
+-
+-	/* fallocate always requiring blocking context */
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-	ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
+-				req->sync.len);
+-	if (ret < 0)
+-		req_set_fail(req);
+-	else
+-		fsnotify_modify(req->file);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	const char __user *fname;
+-	int ret;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (unlikely(sqe->ioprio || sqe->buf_index))
+-		return -EINVAL;
+-	if (unlikely(req->flags & REQ_F_FIXED_FILE))
+-		return -EBADF;
+-
+-	/* open.how should be already initialised */
+-	if (!(req->open.how.flags & O_PATH) && force_o_largefile())
+-		req->open.how.flags |= O_LARGEFILE;
+-
+-	req->open.dfd = READ_ONCE(sqe->fd);
+-	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	req->open.filename = getname(fname);
+-	if (IS_ERR(req->open.filename)) {
+-		ret = PTR_ERR(req->open.filename);
+-		req->open.filename = NULL;
+-		return ret;
+-	}
+-
+-	req->open.file_slot = READ_ONCE(sqe->file_index);
+-	if (req->open.file_slot && (req->open.how.flags & O_CLOEXEC))
+-		return -EINVAL;
+-
+-	req->open.nofile = rlimit(RLIMIT_NOFILE);
+-	req->flags |= REQ_F_NEED_CLEANUP;
+-	return 0;
+-}
+-
+-static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	u64 mode = READ_ONCE(sqe->len);
+-	u64 flags = READ_ONCE(sqe->open_flags);
+-
+-	req->open.how = build_open_how(flags, mode);
+-	return __io_openat_prep(req, sqe);
+-}
+-
+-static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct open_how __user *how;
+-	size_t len;
+-	int ret;
+-
+-	how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+-	len = READ_ONCE(sqe->len);
+-	if (len < OPEN_HOW_SIZE_VER0)
+-		return -EINVAL;
+-
+-	ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
+-					len);
+-	if (ret)
+-		return ret;
+-
+-	return __io_openat_prep(req, sqe);
+-}
+-
+-static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct open_flags op;
+-	struct file *file;
+-	bool resolve_nonblock, nonblock_set;
+-	bool fixed = !!req->open.file_slot;
+-	int ret;
+-
+-	ret = build_open_flags(&req->open.how, &op);
+-	if (ret)
+-		goto err;
+-	nonblock_set = op.open_flag & O_NONBLOCK;
+-	resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
+-	if (issue_flags & IO_URING_F_NONBLOCK) {
+-		/*
+-		 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
+-		 * it'll always -EAGAIN
+-		 */
+-		if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
+-			return -EAGAIN;
+-		op.lookup_flags |= LOOKUP_CACHED;
+-		op.open_flag |= O_NONBLOCK;
+-	}
+-
+-	if (!fixed) {
+-		ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
+-		if (ret < 0)
+-			goto err;
+-	}
+-
+-	file = do_filp_open(req->open.dfd, req->open.filename, &op);
+-	if (IS_ERR(file)) {
+-		/*
+-		 * We could hang on to this 'fd' on retrying, but seems like
+-		 * marginal gain for something that is now known to be a slower
+-		 * path. So just put it, and we'll get a new one when we retry.
+-		 */
+-		if (!fixed)
+-			put_unused_fd(ret);
+-
+-		ret = PTR_ERR(file);
+-		/* only retry if RESOLVE_CACHED wasn't already set by application */
+-		if (ret == -EAGAIN &&
+-		    (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)))
+-			return -EAGAIN;
+-		goto err;
+-	}
+-
+-	if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
+-		file->f_flags &= ~O_NONBLOCK;
+-	fsnotify_open(file);
+-
+-	if (!fixed)
+-		fd_install(ret, file);
+-	else
+-		ret = io_install_fixed_file(req, file, issue_flags,
+-					    req->open.file_slot - 1);
+-err:
+-	putname(req->open.filename);
+-	req->flags &= ~REQ_F_NEED_CLEANUP;
+-	if (ret < 0)
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-
+-static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	return io_openat2(req, issue_flags);
+-}
+-
+-static int io_remove_buffers_prep(struct io_kiocb *req,
+-				  const struct io_uring_sqe *sqe)
+-{
+-	struct io_provide_buf *p = &req->pbuf;
+-	u64 tmp;
+-
+-	if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off ||
+-	    sqe->splice_fd_in)
+-		return -EINVAL;
+-
+-	tmp = READ_ONCE(sqe->fd);
+-	if (!tmp || tmp > USHRT_MAX)
+-		return -EINVAL;
+-
+-	memset(p, 0, sizeof(*p));
+-	p->nbufs = tmp;
+-	p->bgid = READ_ONCE(sqe->buf_group);
+-	return 0;
+-}
+-
+-static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
+-			       int bgid, unsigned nbufs)
+-{
+-	unsigned i = 0;
+-
+-	/* shouldn't happen */
+-	if (!nbufs)
+-		return 0;
+-
+-	/* the head kbuf is the list itself */
+-	while (!list_empty(&buf->list)) {
+-		struct io_buffer *nxt;
+-
+-		nxt = list_first_entry(&buf->list, struct io_buffer, list);
+-		list_del(&nxt->list);
+-		kfree(nxt);
+-		if (++i == nbufs)
+-			return i;
+-		cond_resched();
+-	}
+-	i++;
+-	kfree(buf);
+-	xa_erase(&ctx->io_buffers, bgid);
+-
+-	return i;
+-}
+-
+-static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_provide_buf *p = &req->pbuf;
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_buffer *head;
+-	int ret = 0;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-
+-	io_ring_submit_lock(ctx, !force_nonblock);
+-
+-	lockdep_assert_held(&ctx->uring_lock);
+-
+-	ret = -ENOENT;
+-	head = xa_load(&ctx->io_buffers, p->bgid);
+-	if (head)
+-		ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
+-	if (ret < 0)
+-		req_set_fail(req);
+-
+-	/* complete before unlock, IOPOLL may need the lock */
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	io_ring_submit_unlock(ctx, !force_nonblock);
+-	return 0;
+-}
+-
+-static int io_provide_buffers_prep(struct io_kiocb *req,
+-				   const struct io_uring_sqe *sqe)
+-{
+-	unsigned long size, tmp_check;
+-	struct io_provide_buf *p = &req->pbuf;
+-	u64 tmp;
+-
+-	if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
+-		return -EINVAL;
+-
+-	tmp = READ_ONCE(sqe->fd);
+-	if (!tmp || tmp > USHRT_MAX)
+-		return -E2BIG;
+-	p->nbufs = tmp;
+-	p->addr = READ_ONCE(sqe->addr);
+-	p->len = READ_ONCE(sqe->len);
+-
+-	if (check_mul_overflow((unsigned long)p->len, (unsigned long)p->nbufs,
+-				&size))
+-		return -EOVERFLOW;
+-	if (check_add_overflow((unsigned long)p->addr, size, &tmp_check))
+-		return -EOVERFLOW;
+-
+-	size = (unsigned long)p->len * p->nbufs;
+-	if (!access_ok(u64_to_user_ptr(p->addr), size))
+-		return -EFAULT;
+-
+-	p->bgid = READ_ONCE(sqe->buf_group);
+-	tmp = READ_ONCE(sqe->off);
+-	if (tmp > USHRT_MAX)
+-		return -E2BIG;
+-	p->bid = tmp;
+-	return 0;
+-}
+-
+-static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
+-{
+-	struct io_buffer *buf;
+-	u64 addr = pbuf->addr;
+-	int i, bid = pbuf->bid;
+-
+-	for (i = 0; i < pbuf->nbufs; i++) {
+-		buf = kmalloc(sizeof(*buf), GFP_KERNEL_ACCOUNT);
+-		if (!buf)
+-			break;
+-
+-		buf->addr = addr;
+-		buf->len = min_t(__u32, pbuf->len, MAX_RW_COUNT);
+-		buf->bid = bid;
+-		addr += pbuf->len;
+-		bid++;
+-		if (!*head) {
+-			INIT_LIST_HEAD(&buf->list);
+-			*head = buf;
+-		} else {
+-			list_add_tail(&buf->list, &(*head)->list);
+-		}
+-		cond_resched();
+-	}
+-
+-	return i ? i : -ENOMEM;
+-}
+-
+-static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_provide_buf *p = &req->pbuf;
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_buffer *head, *list;
+-	int ret = 0;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-
+-	io_ring_submit_lock(ctx, !force_nonblock);
+-
+-	lockdep_assert_held(&ctx->uring_lock);
+-
+-	list = head = xa_load(&ctx->io_buffers, p->bgid);
+-
+-	ret = io_add_buffers(p, &head);
+-	if (ret >= 0 && !list) {
+-		ret = xa_insert(&ctx->io_buffers, p->bgid, head,
+-				GFP_KERNEL_ACCOUNT);
+-		if (ret < 0)
+-			__io_remove_buffers(ctx, head, p->bgid, -1U);
+-	}
+-	if (ret < 0)
+-		req_set_fail(req);
+-	/* complete before unlock, IOPOLL may need the lock */
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	io_ring_submit_unlock(ctx, !force_nonblock);
+-	return 0;
+-}
+-
+-static int io_epoll_ctl_prep(struct io_kiocb *req,
+-			     const struct io_uring_sqe *sqe)
+-{
+-#if defined(CONFIG_EPOLL)
+-	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-
+-	req->epoll.epfd = READ_ONCE(sqe->fd);
+-	req->epoll.op = READ_ONCE(sqe->len);
+-	req->epoll.fd = READ_ONCE(sqe->off);
+-
+-	if (ep_op_has_event(req->epoll.op)) {
+-		struct epoll_event __user *ev;
+-
+-		ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-		if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
+-			return -EFAULT;
+-	}
+-
+-	return 0;
+-#else
+-	return -EOPNOTSUPP;
+-#endif
+-}
+-
+-static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-#if defined(CONFIG_EPOLL)
+-	struct io_epoll *ie = &req->epoll;
+-	int ret;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-
+-	ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
+-	if (force_nonblock && ret == -EAGAIN)
+-		return -EAGAIN;
+-
+-	if (ret < 0)
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-#else
+-	return -EOPNOTSUPP;
+-#endif
+-}
+-
+-static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
+-	if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-
+-	req->madvise.addr = READ_ONCE(sqe->addr);
+-	req->madvise.len = READ_ONCE(sqe->len);
+-	req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
+-	return 0;
+-#else
+-	return -EOPNOTSUPP;
+-#endif
+-}
+-
+-static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
+-	struct io_madvise *ma = &req->madvise;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-#else
+-	return -EOPNOTSUPP;
+-#endif
+-}
+-
+-static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	if (sqe->ioprio || sqe->buf_index || sqe->addr || sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-
+-	req->fadvise.offset = READ_ONCE(sqe->off);
+-	req->fadvise.len = READ_ONCE(sqe->len);
+-	req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
+-	return 0;
+-}
+-
+-static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_fadvise *fa = &req->fadvise;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK) {
+-		switch (fa->advice) {
+-		case POSIX_FADV_NORMAL:
+-		case POSIX_FADV_RANDOM:
+-		case POSIX_FADV_SEQUENTIAL:
+-			break;
+-		default:
+-			return -EAGAIN;
+-		}
+-	}
+-
+-	ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
+-	if (ret < 0)
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-
+-static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (req->flags & REQ_F_FIXED_FILE)
+-		return -EBADF;
+-
+-	req->statx.dfd = READ_ONCE(sqe->fd);
+-	req->statx.mask = READ_ONCE(sqe->len);
+-	req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+-	req->statx.flags = READ_ONCE(sqe->statx_flags);
+-
+-	return 0;
+-}
+-
+-static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_statx *ctx = &req->statx;
+-	int ret;
+-
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
+-		       ctx->buffer);
+-
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
+-	    sqe->rw_flags || sqe->buf_index)
+-		return -EINVAL;
+-	if (req->flags & REQ_F_FIXED_FILE)
+-		return -EBADF;
+-
+-	req->close.fd = READ_ONCE(sqe->fd);
+-	req->close.file_slot = READ_ONCE(sqe->file_index);
+-	if (req->close.file_slot && req->close.fd)
+-		return -EINVAL;
+-
+-	return 0;
+-}
+-
+-static int io_close(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct files_struct *files = current->files;
+-	struct io_close *close = &req->close;
+-	struct fdtable *fdt;
+-	struct file *file = NULL;
+-	int ret = -EBADF;
+-
+-	if (req->close.file_slot) {
+-		ret = io_close_fixed(req, issue_flags);
+-		goto err;
+-	}
+-
+-	spin_lock(&files->file_lock);
+-	fdt = files_fdtable(files);
+-	if (close->fd >= fdt->max_fds) {
+-		spin_unlock(&files->file_lock);
+-		goto err;
+-	}
+-	file = fdt->fd[close->fd];
+-	if (!file || file->f_op == &io_uring_fops) {
+-		spin_unlock(&files->file_lock);
+-		file = NULL;
+-		goto err;
+-	}
+-
+-	/* if the file has a flush method, be safe and punt to async */
+-	if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
+-		spin_unlock(&files->file_lock);
+-		return -EAGAIN;
+-	}
+-
+-	ret = __close_fd_get_file(close->fd, &file);
+-	spin_unlock(&files->file_lock);
+-	if (ret < 0) {
+-		if (ret == -ENOENT)
+-			ret = -EBADF;
+-		goto err;
+-	}
+-
+-	/* No ->flush() or already async, safely close from here */
+-	ret = filp_close(file, current->files);
+-err:
+-	if (ret < 0)
+-		req_set_fail(req);
+-	if (file)
+-		fput(file);
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-
+-static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
+-		     sqe->splice_fd_in))
+-		return -EINVAL;
+-
+-	req->sync.off = READ_ONCE(sqe->off);
+-	req->sync.len = READ_ONCE(sqe->len);
+-	req->sync.flags = READ_ONCE(sqe->sync_range_flags);
+-	return 0;
+-}
+-
+-static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	int ret;
+-
+-	/* sync_file_range always requires a blocking context */
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		return -EAGAIN;
+-
+-	ret = sync_file_range(req->file, req->sync.off, req->sync.len,
+-				req->sync.flags);
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-#if defined(CONFIG_NET)
+-static int io_setup_async_msg(struct io_kiocb *req,
+-			      struct io_async_msghdr *kmsg)
+-{
+-	struct io_async_msghdr *async_msg = req->async_data;
+-
+-	if (async_msg)
+-		return -EAGAIN;
+-	if (io_alloc_async_data(req)) {
+-		kfree(kmsg->free_iov);
+-		return -ENOMEM;
+-	}
+-	async_msg = req->async_data;
+-	req->flags |= REQ_F_NEED_CLEANUP;
+-	memcpy(async_msg, kmsg, sizeof(*kmsg));
+-	if (async_msg->msg.msg_name)
+-		async_msg->msg.msg_name = &async_msg->addr;
+-	/* if were using fast_iov, set it to the new one */
+-	if (!async_msg->free_iov)
+-		async_msg->msg.msg_iter.iov = async_msg->fast_iov;
+-
+-	return -EAGAIN;
+-}
+-
+-static int io_sendmsg_copy_hdr(struct io_kiocb *req,
+-			       struct io_async_msghdr *iomsg)
+-{
+-	iomsg->msg.msg_name = &iomsg->addr;
+-	iomsg->free_iov = iomsg->fast_iov;
+-	return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
+-				   req->sr_msg.msg_flags, &iomsg->free_iov);
+-}
+-
+-static int io_sendmsg_prep_async(struct io_kiocb *req)
+-{
+-	int ret;
+-
+-	ret = io_sendmsg_copy_hdr(req, req->async_data);
+-	if (!ret)
+-		req->flags |= REQ_F_NEED_CLEANUP;
+-	return ret;
+-}
+-
+-static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct io_sr_msg *sr = &req->sr_msg;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (unlikely(sqe->addr2 || sqe->file_index))
+-		return -EINVAL;
+-	if (unlikely(sqe->addr2 || sqe->file_index || sqe->ioprio))
+-		return -EINVAL;
+-
+-	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	sr->len = READ_ONCE(sqe->len);
+-	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
+-	if (sr->msg_flags & MSG_DONTWAIT)
+-		req->flags |= REQ_F_NOWAIT;
+-
+-#ifdef CONFIG_COMPAT
+-	if (req->ctx->compat)
+-		sr->msg_flags |= MSG_CMSG_COMPAT;
+-#endif
+-	return 0;
+-}
+-
+-static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_async_msghdr iomsg, *kmsg;
+-	struct socket *sock;
+-	unsigned flags;
+-	int min_ret = 0;
+-	int ret;
+-
+-	sock = sock_from_file(req->file);
+-	if (unlikely(!sock))
+-		return -ENOTSOCK;
+-
+-	kmsg = req->async_data;
+-	if (!kmsg) {
+-		ret = io_sendmsg_copy_hdr(req, &iomsg);
+-		if (ret)
+-			return ret;
+-		kmsg = &iomsg;
+-	}
+-
+-	flags = req->sr_msg.msg_flags;
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		flags |= MSG_DONTWAIT;
+-	if (flags & MSG_WAITALL)
+-		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+-
+-	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
+-	if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
+-		return io_setup_async_msg(req, kmsg);
+-	if (ret == -ERESTARTSYS)
+-		ret = -EINTR;
+-
+-	/* fast path, check for non-NULL to avoid function call */
+-	if (kmsg->free_iov)
+-		kfree(kmsg->free_iov);
+-	req->flags &= ~REQ_F_NEED_CLEANUP;
+-	if (ret < min_ret)
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-
+-static int io_send(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_sr_msg *sr = &req->sr_msg;
+-	struct msghdr msg;
+-	struct iovec iov;
+-	struct socket *sock;
+-	unsigned flags;
+-	int min_ret = 0;
+-	int ret;
+-
+-	sock = sock_from_file(req->file);
+-	if (unlikely(!sock))
+-		return -ENOTSOCK;
+-
+-	ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
+-	if (unlikely(ret))
+-		return ret;
+-
+-	msg.msg_name = NULL;
+-	msg.msg_control = NULL;
+-	msg.msg_controllen = 0;
+-	msg.msg_namelen = 0;
+-
+-	flags = req->sr_msg.msg_flags;
+-	if (issue_flags & IO_URING_F_NONBLOCK)
+-		flags |= MSG_DONTWAIT;
+-	if (flags & MSG_WAITALL)
+-		min_ret = iov_iter_count(&msg.msg_iter);
+-
+-	msg.msg_flags = flags;
+-	ret = sock_sendmsg(sock, &msg);
+-	if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
+-		return -EAGAIN;
+-	if (ret == -ERESTARTSYS)
+-		ret = -EINTR;
+-
+-	if (ret < min_ret)
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-
+-static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
+-				 struct io_async_msghdr *iomsg)
+-{
+-	struct io_sr_msg *sr = &req->sr_msg;
+-	struct iovec __user *uiov;
+-	size_t iov_len;
+-	int ret;
+-
+-	ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
+-					&iomsg->uaddr, &uiov, &iov_len);
+-	if (ret)
+-		return ret;
+-
+-	if (req->flags & REQ_F_BUFFER_SELECT) {
+-		if (iov_len > 1)
+-			return -EINVAL;
+-		if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
+-			return -EFAULT;
+-		sr->len = iomsg->fast_iov[0].iov_len;
+-		iomsg->free_iov = NULL;
+-	} else {
+-		iomsg->free_iov = iomsg->fast_iov;
+-		ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
+-				     &iomsg->free_iov, &iomsg->msg.msg_iter,
+-				     false);
+-		if (ret > 0)
+-			ret = 0;
+-	}
+-
+-	return ret;
+-}
+-
+-#ifdef CONFIG_COMPAT
+-static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
+-					struct io_async_msghdr *iomsg)
+-{
+-	struct io_sr_msg *sr = &req->sr_msg;
+-	struct compat_iovec __user *uiov;
+-	compat_uptr_t ptr;
+-	compat_size_t len;
+-	int ret;
+-
+-	ret = __get_compat_msghdr(&iomsg->msg, sr->umsg_compat, &iomsg->uaddr,
+-				  &ptr, &len);
+-	if (ret)
+-		return ret;
+-
+-	uiov = compat_ptr(ptr);
+-	if (req->flags & REQ_F_BUFFER_SELECT) {
+-		compat_ssize_t clen;
+-
+-		if (len > 1)
+-			return -EINVAL;
+-		if (!access_ok(uiov, sizeof(*uiov)))
+-			return -EFAULT;
+-		if (__get_user(clen, &uiov->iov_len))
+-			return -EFAULT;
+-		if (clen < 0)
+-			return -EINVAL;
+-		sr->len = clen;
+-		iomsg->free_iov = NULL;
+-	} else {
+-		iomsg->free_iov = iomsg->fast_iov;
+-		ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
+-				   UIO_FASTIOV, &iomsg->free_iov,
+-				   &iomsg->msg.msg_iter, true);
+-		if (ret < 0)
+-			return ret;
+-	}
+-
+-	return 0;
+-}
+-#endif
+-
+-static int io_recvmsg_copy_hdr(struct io_kiocb *req,
+-			       struct io_async_msghdr *iomsg)
+-{
+-	iomsg->msg.msg_name = &iomsg->addr;
+-
+-#ifdef CONFIG_COMPAT
+-	if (req->ctx->compat)
+-		return __io_compat_recvmsg_copy_hdr(req, iomsg);
+-#endif
+-
+-	return __io_recvmsg_copy_hdr(req, iomsg);
+-}
+-
+-static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
+-					       bool needs_lock)
+-{
+-	struct io_sr_msg *sr = &req->sr_msg;
+-	struct io_buffer *kbuf;
+-
+-	kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
+-	if (IS_ERR(kbuf))
+-		return kbuf;
+-
+-	sr->kbuf = kbuf;
+-	req->flags |= REQ_F_BUFFER_SELECTED;
+-	return kbuf;
+-}
+-
+-static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
+-{
+-	return io_put_kbuf(req, req->sr_msg.kbuf);
+-}
+-
+-static int io_recvmsg_prep_async(struct io_kiocb *req)
+-{
+-	int ret;
+-
+-	ret = io_recvmsg_copy_hdr(req, req->async_data);
+-	if (!ret)
+-		req->flags |= REQ_F_NEED_CLEANUP;
+-	return ret;
+-}
+-
+-static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct io_sr_msg *sr = &req->sr_msg;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (unlikely(sqe->addr2 || sqe->file_index))
+-		return -EINVAL;
+-	if (unlikely(sqe->addr2 || sqe->file_index || sqe->ioprio))
+-		return -EINVAL;
+-
+-	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	sr->len = READ_ONCE(sqe->len);
+-	sr->bgid = READ_ONCE(sqe->buf_group);
+-	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
+-	if (sr->msg_flags & MSG_DONTWAIT)
+-		req->flags |= REQ_F_NOWAIT;
+-
+-#ifdef CONFIG_COMPAT
+-	if (req->ctx->compat)
+-		sr->msg_flags |= MSG_CMSG_COMPAT;
+-#endif
+-	return 0;
+-}
+-
+-static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_async_msghdr iomsg, *kmsg;
+-	struct socket *sock;
+-	struct io_buffer *kbuf;
+-	unsigned flags;
+-	int min_ret = 0;
+-	int ret, cflags = 0;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-
+-	sock = sock_from_file(req->file);
+-	if (unlikely(!sock))
+-		return -ENOTSOCK;
+-
+-	kmsg = req->async_data;
+-	if (!kmsg) {
+-		ret = io_recvmsg_copy_hdr(req, &iomsg);
+-		if (ret)
+-			return ret;
+-		kmsg = &iomsg;
+-	}
+-
+-	if (req->flags & REQ_F_BUFFER_SELECT) {
+-		kbuf = io_recv_buffer_select(req, !force_nonblock);
+-		if (IS_ERR(kbuf))
+-			return PTR_ERR(kbuf);
+-		kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
+-		kmsg->fast_iov[0].iov_len = req->sr_msg.len;
+-		iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov,
+-				1, req->sr_msg.len);
+-	}
+-
+-	flags = req->sr_msg.msg_flags;
+-	if (force_nonblock)
+-		flags |= MSG_DONTWAIT;
+-	if (flags & MSG_WAITALL)
+-		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
+-
+-	ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
+-					kmsg->uaddr, flags);
+-	if (force_nonblock && ret == -EAGAIN)
+-		return io_setup_async_msg(req, kmsg);
+-	if (ret == -ERESTARTSYS)
+-		ret = -EINTR;
+-
+-	if (req->flags & REQ_F_BUFFER_SELECTED)
+-		cflags = io_put_recv_kbuf(req);
+-	/* fast path, check for non-NULL to avoid function call */
+-	if (kmsg->free_iov)
+-		kfree(kmsg->free_iov);
+-	req->flags &= ~REQ_F_NEED_CLEANUP;
+-	if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, cflags);
+-	return 0;
+-}
+-
+-static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_buffer *kbuf;
+-	struct io_sr_msg *sr = &req->sr_msg;
+-	struct msghdr msg;
+-	void __user *buf = sr->buf;
+-	struct socket *sock;
+-	struct iovec iov;
+-	unsigned flags;
+-	int min_ret = 0;
+-	int ret, cflags = 0;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-
+-	sock = sock_from_file(req->file);
+-	if (unlikely(!sock))
+-		return -ENOTSOCK;
+-
+-	if (req->flags & REQ_F_BUFFER_SELECT) {
+-		kbuf = io_recv_buffer_select(req, !force_nonblock);
+-		if (IS_ERR(kbuf))
+-			return PTR_ERR(kbuf);
+-		buf = u64_to_user_ptr(kbuf->addr);
+-	}
+-
+-	ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
+-	if (unlikely(ret))
+-		goto out_free;
+-
+-	msg.msg_name = NULL;
+-	msg.msg_control = NULL;
+-	msg.msg_controllen = 0;
+-	msg.msg_namelen = 0;
+-	msg.msg_iocb = NULL;
+-	msg.msg_flags = 0;
+-
+-	flags = req->sr_msg.msg_flags;
+-	if (force_nonblock)
+-		flags |= MSG_DONTWAIT;
+-	if (flags & MSG_WAITALL)
+-		min_ret = iov_iter_count(&msg.msg_iter);
+-
+-	ret = sock_recvmsg(sock, &msg, flags);
+-	if (force_nonblock && ret == -EAGAIN)
+-		return -EAGAIN;
+-	if (ret == -ERESTARTSYS)
+-		ret = -EINTR;
+-out_free:
+-	if (req->flags & REQ_F_BUFFER_SELECTED)
+-		cflags = io_put_recv_kbuf(req);
+-	if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, cflags);
+-	return 0;
+-}
+-
+-static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct io_accept *accept = &req->accept;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->len || sqe->buf_index)
+-		return -EINVAL;
+-
+-	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
+-	accept->flags = READ_ONCE(sqe->accept_flags);
+-	accept->nofile = rlimit(RLIMIT_NOFILE);
+-
+-	accept->file_slot = READ_ONCE(sqe->file_index);
+-	if (accept->file_slot && (accept->flags & SOCK_CLOEXEC))
+-		return -EINVAL;
+-	if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
+-		return -EINVAL;
+-	if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
+-		accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
+-	return 0;
+-}
+-
+-static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_accept *accept = &req->accept;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-	unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
+-	bool fixed = !!accept->file_slot;
+-	struct file *file;
+-	int ret, fd;
+-
+-	if (req->file->f_flags & O_NONBLOCK)
+-		req->flags |= REQ_F_NOWAIT;
+-
+-	if (!fixed) {
+-		fd = __get_unused_fd_flags(accept->flags, accept->nofile);
+-		if (unlikely(fd < 0))
+-			return fd;
+-	}
+-	file = do_accept(req->file, file_flags, accept->addr, accept->addr_len,
+-			 accept->flags);
+-	if (IS_ERR(file)) {
+-		if (!fixed)
+-			put_unused_fd(fd);
+-		ret = PTR_ERR(file);
+-		if (ret == -EAGAIN && force_nonblock)
+-			return -EAGAIN;
+-		if (ret == -ERESTARTSYS)
+-			ret = -EINTR;
+-		req_set_fail(req);
+-	} else if (!fixed) {
+-		fd_install(fd, file);
+-		ret = fd;
+-	} else {
+-		ret = io_install_fixed_file(req, file, issue_flags,
+-					    accept->file_slot - 1);
+-	}
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-
+-static int io_connect_prep_async(struct io_kiocb *req)
+-{
+-	struct io_async_connect *io = req->async_data;
+-	struct io_connect *conn = &req->connect;
+-
+-	return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
+-}
+-
+-static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct io_connect *conn = &req->connect;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags ||
+-	    sqe->splice_fd_in)
+-		return -EINVAL;
+-
+-	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
+-	conn->addr_len =  READ_ONCE(sqe->addr2);
+-	return 0;
+-}
+-
+-static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_async_connect __io, *io;
+-	unsigned file_flags;
+-	int ret;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-
+-	if (req->async_data) {
+-		io = req->async_data;
+-	} else {
+-		ret = move_addr_to_kernel(req->connect.addr,
+-						req->connect.addr_len,
+-						&__io.address);
+-		if (ret)
+-			goto out;
+-		io = &__io;
+-	}
+-
+-	file_flags = force_nonblock ? O_NONBLOCK : 0;
+-
+-	ret = __sys_connect_file(req->file, &io->address,
+-					req->connect.addr_len, file_flags);
+-	if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
+-		if (req->async_data)
+-			return -EAGAIN;
+-		if (io_alloc_async_data(req)) {
+-			ret = -ENOMEM;
+-			goto out;
+-		}
+-		memcpy(req->async_data, &__io, sizeof(__io));
+-		return -EAGAIN;
+-	}
+-	if (ret == -ERESTARTSYS)
+-		ret = -EINTR;
+-out:
+-	if (ret < 0)
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-#else /* !CONFIG_NET */
+-#define IO_NETOP_FN(op)							\
+-static int io_##op(struct io_kiocb *req, unsigned int issue_flags)	\
+-{									\
+-	return -EOPNOTSUPP;						\
+-}
+-
+-#define IO_NETOP_PREP(op)						\
+-IO_NETOP_FN(op)								\
+-static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
+-{									\
+-	return -EOPNOTSUPP;						\
+-}									\
+-
+-#define IO_NETOP_PREP_ASYNC(op)						\
+-IO_NETOP_PREP(op)							\
+-static int io_##op##_prep_async(struct io_kiocb *req)			\
+-{									\
+-	return -EOPNOTSUPP;						\
+-}
+-
+-IO_NETOP_PREP_ASYNC(sendmsg);
+-IO_NETOP_PREP_ASYNC(recvmsg);
+-IO_NETOP_PREP_ASYNC(connect);
+-IO_NETOP_PREP(accept);
+-IO_NETOP_FN(send);
+-IO_NETOP_FN(recv);
+-#endif /* CONFIG_NET */
+-
+-struct io_poll_table {
+-	struct poll_table_struct pt;
+-	struct io_kiocb *req;
+-	int nr_entries;
+-	int error;
+-};
+-
+-#define IO_POLL_CANCEL_FLAG	BIT(31)
+-#define IO_POLL_RETRY_FLAG	BIT(30)
+-#define IO_POLL_REF_MASK	GENMASK(29, 0)
+-
+-/*
+- * We usually have 1-2 refs taken, 128 is more than enough and we want to
+- * maximise the margin between this amount and the moment when it overflows.
+- */
+-#define IO_POLL_REF_BIAS       128
+-
+-static bool io_poll_get_ownership_slowpath(struct io_kiocb *req)
+-{
+-	int v;
+-
+-	/*
+-	 * poll_refs are already elevated and we don't have much hope for
+-	 * grabbing the ownership. Instead of incrementing set a retry flag
+-	 * to notify the loop that there might have been some change.
+-	 */
+-	v = atomic_fetch_or(IO_POLL_RETRY_FLAG, &req->poll_refs);
+-	if (v & IO_POLL_REF_MASK)
+-		return false;
+-	return !(atomic_fetch_inc(&req->poll_refs) & IO_POLL_REF_MASK);
+-}
+-
+-/*
+- * If refs part of ->poll_refs (see IO_POLL_REF_MASK) is 0, it's free. We can
+- * bump it and acquire ownership. It's disallowed to modify requests while not
+- * owning it, that prevents from races for enqueueing task_work's and b/w
+- * arming poll and wakeups.
+- */
+-static inline bool io_poll_get_ownership(struct io_kiocb *req)
+-{
+-	if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS))
+-		return io_poll_get_ownership_slowpath(req);
+-	return !(atomic_fetch_inc(&req->poll_refs) & IO_POLL_REF_MASK);
+-}
+-
+-static void io_poll_mark_cancelled(struct io_kiocb *req)
+-{
+-	atomic_or(IO_POLL_CANCEL_FLAG, &req->poll_refs);
+-}
+-
+-static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
+-{
+-	/* pure poll stashes this in ->async_data, poll driven retry elsewhere */
+-	if (req->opcode == IORING_OP_POLL_ADD)
+-		return req->async_data;
+-	return req->apoll->double_poll;
+-}
+-
+-static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
+-{
+-	if (req->opcode == IORING_OP_POLL_ADD)
+-		return &req->poll;
+-	return &req->apoll->poll;
+-}
+-
+-static void io_poll_req_insert(struct io_kiocb *req)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct hlist_head *list;
+-
+-	list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
+-	hlist_add_head(&req->hash_node, list);
+-}
+-
+-static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
+-			      wait_queue_func_t wake_func)
+-{
+-	poll->head = NULL;
+-#define IO_POLL_UNMASK	(EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
+-	/* mask in events that we always want/need */
+-	poll->events = events | IO_POLL_UNMASK;
+-	INIT_LIST_HEAD(&poll->wait.entry);
+-	init_waitqueue_func_entry(&poll->wait, wake_func);
+-}
+-
+-static inline void io_poll_remove_entry(struct io_poll_iocb *poll)
+-{
+-	struct wait_queue_head *head = smp_load_acquire(&poll->head);
+-
+-	if (head) {
+-		spin_lock_irq(&head->lock);
+-		list_del_init(&poll->wait.entry);
+-		poll->head = NULL;
+-		spin_unlock_irq(&head->lock);
+-	}
+-}
+-
+-static void io_poll_remove_entries(struct io_kiocb *req)
+-{
+-	struct io_poll_iocb *poll = io_poll_get_single(req);
+-	struct io_poll_iocb *poll_double = io_poll_get_double(req);
+-
+-	/*
+-	 * While we hold the waitqueue lock and the waitqueue is nonempty,
+-	 * wake_up_pollfree() will wait for us.  However, taking the waitqueue
+-	 * lock in the first place can race with the waitqueue being freed.
+-	 *
+-	 * We solve this as eventpoll does: by taking advantage of the fact that
+-	 * all users of wake_up_pollfree() will RCU-delay the actual free.  If
+-	 * we enter rcu_read_lock() and see that the pointer to the queue is
+-	 * non-NULL, we can then lock it without the memory being freed out from
+-	 * under us.
+-	 *
+-	 * Keep holding rcu_read_lock() as long as we hold the queue lock, in
+-	 * case the caller deletes the entry from the queue, leaving it empty.
+-	 * In that case, only RCU prevents the queue memory from being freed.
+-	 */
+-	rcu_read_lock();
+-	io_poll_remove_entry(poll);
+-	if (poll_double)
+-		io_poll_remove_entry(poll_double);
+-	rcu_read_unlock();
+-}
+-
+-/*
+- * All poll tw should go through this. Checks for poll events, manages
+- * references, does rewait, etc.
+- *
+- * Returns a negative error on failure. >0 when no action require, which is
+- * either spurious wakeup or multishot CQE is served. 0 when it's done with
+- * the request, then the mask is stored in req->result.
+- */
+-static int io_poll_check_events(struct io_kiocb *req)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_poll_iocb *poll = io_poll_get_single(req);
+-	int v;
+-
+-	/* req->task == current here, checking PF_EXITING is safe */
+-	if (unlikely(req->task->flags & PF_EXITING))
+-		io_poll_mark_cancelled(req);
+-
+-	do {
+-		v = atomic_read(&req->poll_refs);
+-
+-		/* tw handler should be the owner, and so have some references */
+-		if (WARN_ON_ONCE(!(v & IO_POLL_REF_MASK)))
+-			return 0;
+-		if (v & IO_POLL_CANCEL_FLAG)
+-			return -ECANCELED;
+-		/*
+-		 * cqe.res contains only events of the first wake up
+-		 * and all others are be lost. Redo vfs_poll() to get
+-		 * up to date state.
+-		 */
+-		if ((v & IO_POLL_REF_MASK) != 1)
+-			req->result = 0;
+-		if (v & IO_POLL_RETRY_FLAG) {
+-			req->result = 0;
+-			/*
+-			 * We won't find new events that came in between
+-			 * vfs_poll and the ref put unless we clear the
+-			 * flag in advance.
+-			 */
+-			atomic_andnot(IO_POLL_RETRY_FLAG, &req->poll_refs);
+-			v &= ~IO_POLL_RETRY_FLAG;
+-		}
+-
+-		if (!req->result) {
+-			struct poll_table_struct pt = { ._key = poll->events };
+-
+-			req->result = vfs_poll(req->file, &pt) & poll->events;
+-		}
+-
+-		/* multishot, just fill an CQE and proceed */
+-		if (req->result && !(poll->events & EPOLLONESHOT)) {
+-			__poll_t mask = mangle_poll(req->result & poll->events);
+-			bool filled;
+-
+-			spin_lock(&ctx->completion_lock);
+-			filled = io_fill_cqe_aux(ctx, req->user_data, mask,
+-						 IORING_CQE_F_MORE);
+-			io_commit_cqring(ctx);
+-			spin_unlock(&ctx->completion_lock);
+-			if (unlikely(!filled))
+-				return -ECANCELED;
+-			io_cqring_ev_posted(ctx);
+-		} else if (req->result) {
+-			return 0;
+-		}
+-
+-		/* force the next iteration to vfs_poll() */
+-		req->result = 0;
+-
+-		/*
+-		 * Release all references, retry if someone tried to restart
+-		 * task_work while we were executing it.
+-		 */
+-	} while (atomic_sub_return(v & IO_POLL_REF_MASK, &req->poll_refs) &
+-					IO_POLL_REF_MASK);
+-
+-	return 1;
+-}
+-
+-static void io_poll_task_func(struct io_kiocb *req, bool *locked)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	int ret;
+-
+-	ret = io_poll_check_events(req);
+-	if (ret > 0)
+-		return;
+-
+-	if (!ret) {
+-		req->result = mangle_poll(req->result & req->poll.events);
+-	} else {
+-		req->result = ret;
+-		req_set_fail(req);
+-	}
+-
+-	io_poll_remove_entries(req);
+-	spin_lock(&ctx->completion_lock);
+-	hash_del(&req->hash_node);
+-	spin_unlock(&ctx->completion_lock);
+-	io_req_complete_post(req, req->result, 0);
+-}
+-
+-static void io_apoll_task_func(struct io_kiocb *req, bool *locked)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	int ret;
+-
+-	ret = io_poll_check_events(req);
+-	if (ret > 0)
+-		return;
+-
+-	io_poll_remove_entries(req);
+-	spin_lock(&ctx->completion_lock);
+-	hash_del(&req->hash_node);
+-	spin_unlock(&ctx->completion_lock);
+-
+-	if (!ret)
+-		io_req_task_submit(req, locked);
+-	else
+-		io_req_complete_failed(req, ret);
+-}
+-
+-static void __io_poll_execute(struct io_kiocb *req, int mask)
+-{
+-	req->result = mask;
+-	if (req->opcode == IORING_OP_POLL_ADD)
+-		req->io_task_work.func = io_poll_task_func;
+-	else
+-		req->io_task_work.func = io_apoll_task_func;
+-
+-	trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
+-	io_req_task_work_add(req);
+-}
+-
+-static inline void io_poll_execute(struct io_kiocb *req, int res)
+-{
+-	if (io_poll_get_ownership(req))
+-		__io_poll_execute(req, res);
+-}
+-
+-static void io_poll_cancel_req(struct io_kiocb *req)
+-{
+-	io_poll_mark_cancelled(req);
+-	/* kick tw, which should complete the request */
+-	io_poll_execute(req, 0);
+-}
+-
+-static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
+-			void *key)
+-{
+-	struct io_kiocb *req = wait->private;
+-	struct io_poll_iocb *poll = container_of(wait, struct io_poll_iocb,
+-						 wait);
+-	__poll_t mask = key_to_poll(key);
+-
+-	if (unlikely(mask & POLLFREE)) {
+-		io_poll_mark_cancelled(req);
+-		/* we have to kick tw in case it's not already */
+-		io_poll_execute(req, 0);
+-
+-		/*
+-		 * If the waitqueue is being freed early but someone is already
+-		 * holds ownership over it, we have to tear down the request as
+-		 * best we can. That means immediately removing the request from
+-		 * its waitqueue and preventing all further accesses to the
+-		 * waitqueue via the request.
+-		 */
+-		list_del_init(&poll->wait.entry);
+-
+-		/*
+-		 * Careful: this *must* be the last step, since as soon
+-		 * as req->head is NULL'ed out, the request can be
+-		 * completed and freed, since aio_poll_complete_work()
+-		 * will no longer need to take the waitqueue lock.
+-		 */
+-		smp_store_release(&poll->head, NULL);
+-		return 1;
+-	}
+-
+-	/* for instances that support it check for an event match first */
+-	if (mask && !(mask & poll->events))
+-		return 0;
+-
+-	if (io_poll_get_ownership(req))
+-		__io_poll_execute(req, mask);
+-	return 1;
+-}
+-
+-static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
+-			    struct wait_queue_head *head,
+-			    struct io_poll_iocb **poll_ptr)
+-{
+-	struct io_kiocb *req = pt->req;
+-
+-	/*
+-	 * The file being polled uses multiple waitqueues for poll handling
+-	 * (e.g. one for read, one for write). Setup a separate io_poll_iocb
+-	 * if this happens.
+-	 */
+-	if (unlikely(pt->nr_entries)) {
+-		struct io_poll_iocb *first = poll;
+-
+-		/* double add on the same waitqueue head, ignore */
+-		if (first->head == head)
+-			return;
+-		/* already have a 2nd entry, fail a third attempt */
+-		if (*poll_ptr) {
+-			if ((*poll_ptr)->head == head)
+-				return;
+-			pt->error = -EINVAL;
+-			return;
+-		}
+-
+-		poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
+-		if (!poll) {
+-			pt->error = -ENOMEM;
+-			return;
+-		}
+-		io_init_poll_iocb(poll, first->events, first->wait.func);
+-		*poll_ptr = poll;
+-	}
+-
+-	pt->nr_entries++;
+-	poll->head = head;
+-	poll->wait.private = req;
+-
+-	if (poll->events & EPOLLEXCLUSIVE)
+-		add_wait_queue_exclusive(head, &poll->wait);
+-	else
+-		add_wait_queue(head, &poll->wait);
+-}
+-
+-static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
+-			       struct poll_table_struct *p)
+-{
+-	struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
+-
+-	__io_queue_proc(&pt->req->poll, pt, head,
+-			(struct io_poll_iocb **) &pt->req->async_data);
+-}
+-
+-static int __io_arm_poll_handler(struct io_kiocb *req,
+-				 struct io_poll_iocb *poll,
+-				 struct io_poll_table *ipt, __poll_t mask)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	INIT_HLIST_NODE(&req->hash_node);
+-	io_init_poll_iocb(poll, mask, io_poll_wake);
+-	poll->file = req->file;
+-	poll->wait.private = req;
+-
+-	ipt->pt._key = mask;
+-	ipt->req = req;
+-	ipt->error = 0;
+-	ipt->nr_entries = 0;
+-
+-	/*
+-	 * Take the ownership to delay any tw execution up until we're done
+-	 * with poll arming. see io_poll_get_ownership().
+-	 */
+-	atomic_set(&req->poll_refs, 1);
+-	mask = vfs_poll(req->file, &ipt->pt) & poll->events;
+-
+-	if (mask && (poll->events & EPOLLONESHOT)) {
+-		io_poll_remove_entries(req);
+-		/* no one else has access to the req, forget about the ref */
+-		return mask;
+-	}
+-	if (!mask && unlikely(ipt->error || !ipt->nr_entries)) {
+-		io_poll_remove_entries(req);
+-		if (!ipt->error)
+-			ipt->error = -EINVAL;
+-		return 0;
+-	}
+-
+-	spin_lock(&ctx->completion_lock);
+-	io_poll_req_insert(req);
+-	spin_unlock(&ctx->completion_lock);
+-
+-	if (mask) {
+-		/* can't multishot if failed, just queue the event we've got */
+-		if (unlikely(ipt->error || !ipt->nr_entries)) {
+-			poll->events |= EPOLLONESHOT;
+-			ipt->error = 0;
+-		}
+-		__io_poll_execute(req, mask);
+-		return 0;
+-	}
+-
+-	/*
+-	 * Try to release ownership. If we see a change of state, e.g.
+-	 * poll was waken up, queue up a tw, it'll deal with it.
+-	 */
+-	if (atomic_cmpxchg(&req->poll_refs, 1, 0) != 1)
+-		__io_poll_execute(req, 0);
+-	return 0;
+-}
+-
+-static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
+-			       struct poll_table_struct *p)
+-{
+-	struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
+-	struct async_poll *apoll = pt->req->apoll;
+-
+-	__io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
+-}
+-
+-enum {
+-	IO_APOLL_OK,
+-	IO_APOLL_ABORTED,
+-	IO_APOLL_READY
+-};
+-
+-static int io_arm_poll_handler(struct io_kiocb *req)
+-{
+-	const struct io_op_def *def = &io_op_defs[req->opcode];
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct async_poll *apoll;
+-	struct io_poll_table ipt;
+-	__poll_t mask = EPOLLONESHOT | POLLERR | POLLPRI;
+-	int ret;
+-
+-	if (!req->file || !file_can_poll(req->file))
+-		return IO_APOLL_ABORTED;
+-	if (req->flags & REQ_F_POLLED)
+-		return IO_APOLL_ABORTED;
+-	if (!def->pollin && !def->pollout)
+-		return IO_APOLL_ABORTED;
+-
+-	if (def->pollin) {
+-		mask |= POLLIN | POLLRDNORM;
+-
+-		/* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
+-		if ((req->opcode == IORING_OP_RECVMSG) &&
+-		    (req->sr_msg.msg_flags & MSG_ERRQUEUE))
+-			mask &= ~POLLIN;
+-	} else {
+-		mask |= POLLOUT | POLLWRNORM;
+-	}
+-
+-	apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
+-	if (unlikely(!apoll))
+-		return IO_APOLL_ABORTED;
+-	apoll->double_poll = NULL;
+-	req->apoll = apoll;
+-	req->flags |= REQ_F_POLLED;
+-	ipt.pt._qproc = io_async_queue_proc;
+-
+-	ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask);
+-	if (ret || ipt.error)
+-		return ret ? IO_APOLL_READY : IO_APOLL_ABORTED;
+-
+-	trace_io_uring_poll_arm(ctx, req, req->opcode, req->user_data,
+-				mask, apoll->poll.events);
+-	return IO_APOLL_OK;
+-}
+-
+-/*
+- * Returns true if we found and killed one or more poll requests
+- */
+-static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
+-			       bool cancel_all)
+-{
+-	struct hlist_node *tmp;
+-	struct io_kiocb *req;
+-	bool found = false;
+-	int i;
+-
+-	spin_lock(&ctx->completion_lock);
+-	for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
+-		struct hlist_head *list;
+-
+-		list = &ctx->cancel_hash[i];
+-		hlist_for_each_entry_safe(req, tmp, list, hash_node) {
+-			if (io_match_task_safe(req, tsk, cancel_all)) {
+-				hlist_del_init(&req->hash_node);
+-				io_poll_cancel_req(req);
+-				found = true;
+-			}
+-		}
+-	}
+-	spin_unlock(&ctx->completion_lock);
+-	return found;
+-}
+-
+-static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, __u64 sqe_addr,
+-				     bool poll_only)
+-	__must_hold(&ctx->completion_lock)
+-{
+-	struct hlist_head *list;
+-	struct io_kiocb *req;
+-
+-	list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
+-	hlist_for_each_entry(req, list, hash_node) {
+-		if (sqe_addr != req->user_data)
+-			continue;
+-		if (poll_only && req->opcode != IORING_OP_POLL_ADD)
+-			continue;
+-		return req;
+-	}
+-	return NULL;
+-}
+-
+-static bool io_poll_disarm(struct io_kiocb *req)
+-	__must_hold(&ctx->completion_lock)
+-{
+-	if (!io_poll_get_ownership(req))
+-		return false;
+-	io_poll_remove_entries(req);
+-	hash_del(&req->hash_node);
+-	return true;
+-}
+-
+-static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr,
+-			  bool poll_only)
+-	__must_hold(&ctx->completion_lock)
+-{
+-	struct io_kiocb *req = io_poll_find(ctx, sqe_addr, poll_only);
+-
+-	if (!req)
+-		return -ENOENT;
+-	io_poll_cancel_req(req);
+-	return 0;
+-}
+-
+-static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
+-				     unsigned int flags)
+-{
+-	u32 events;
+-
+-	events = READ_ONCE(sqe->poll32_events);
+-#ifdef __BIG_ENDIAN
+-	events = swahw32(events);
+-#endif
+-	if (!(flags & IORING_POLL_ADD_MULTI))
+-		events |= EPOLLONESHOT;
+-	return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
+-}
+-
+-static int io_poll_update_prep(struct io_kiocb *req,
+-			       const struct io_uring_sqe *sqe)
+-{
+-	struct io_poll_update *upd = &req->poll_update;
+-	u32 flags;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
+-		return -EINVAL;
+-	flags = READ_ONCE(sqe->len);
+-	if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA |
+-		      IORING_POLL_ADD_MULTI))
+-		return -EINVAL;
+-	/* meaningless without update */
+-	if (flags == IORING_POLL_ADD_MULTI)
+-		return -EINVAL;
+-
+-	upd->old_user_data = READ_ONCE(sqe->addr);
+-	upd->update_events = flags & IORING_POLL_UPDATE_EVENTS;
+-	upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA;
+-
+-	upd->new_user_data = READ_ONCE(sqe->off);
+-	if (!upd->update_user_data && upd->new_user_data)
+-		return -EINVAL;
+-	if (upd->update_events)
+-		upd->events = io_poll_parse_events(sqe, flags);
+-	else if (sqe->poll32_events)
+-		return -EINVAL;
+-
+-	return 0;
+-}
+-
+-static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	struct io_poll_iocb *poll = &req->poll;
+-	u32 flags;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->addr)
+-		return -EINVAL;
+-	flags = READ_ONCE(sqe->len);
+-	if (flags & ~IORING_POLL_ADD_MULTI)
+-		return -EINVAL;
+-
+-	io_req_set_refcount(req);
+-	poll->events = io_poll_parse_events(sqe, flags);
+-	return 0;
+-}
+-
+-static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_poll_iocb *poll = &req->poll;
+-	struct io_poll_table ipt;
+-	int ret;
+-
+-	ipt.pt._qproc = io_poll_queue_proc;
+-
+-	ret = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events);
+-	if (!ret && ipt.error)
+-		req_set_fail(req);
+-	ret = ret ?: ipt.error;
+-	if (ret)
+-		__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-
+-static int io_poll_update(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_kiocb *preq;
+-	int ret2, ret = 0;
+-
+-	spin_lock(&ctx->completion_lock);
+-	preq = io_poll_find(ctx, req->poll_update.old_user_data, true);
+-	if (!preq || !io_poll_disarm(preq)) {
+-		spin_unlock(&ctx->completion_lock);
+-		ret = preq ? -EALREADY : -ENOENT;
+-		goto out;
+-	}
+-	spin_unlock(&ctx->completion_lock);
+-
+-	if (req->poll_update.update_events || req->poll_update.update_user_data) {
+-		/* only mask one event flags, keep behavior flags */
+-		if (req->poll_update.update_events) {
+-			preq->poll.events &= ~0xffff;
+-			preq->poll.events |= req->poll_update.events & 0xffff;
+-			preq->poll.events |= IO_POLL_UNMASK;
+-		}
+-		if (req->poll_update.update_user_data)
+-			preq->user_data = req->poll_update.new_user_data;
+-
+-		ret2 = io_poll_add(preq, issue_flags);
+-		/* successfully updated, don't complete poll request */
+-		if (!ret2)
+-			goto out;
+-	}
+-	req_set_fail(preq);
+-	io_req_complete(preq, -ECANCELED);
+-out:
+-	if (ret < 0)
+-		req_set_fail(req);
+-	/* complete update request, we're done with it */
+-	io_req_complete(req, ret);
+-	return 0;
+-}
+-
+-static void io_req_task_timeout(struct io_kiocb *req, bool *locked)
+-{
+-	req_set_fail(req);
+-	io_req_complete_post(req, -ETIME, 0);
+-}
+-
+-static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
+-{
+-	struct io_timeout_data *data = container_of(timer,
+-						struct io_timeout_data, timer);
+-	struct io_kiocb *req = data->req;
+-	struct io_ring_ctx *ctx = req->ctx;
+-	unsigned long flags;
+-
+-	spin_lock_irqsave(&ctx->timeout_lock, flags);
+-	list_del_init(&req->timeout.list);
+-	atomic_set(&req->ctx->cq_timeouts,
+-		atomic_read(&req->ctx->cq_timeouts) + 1);
+-	spin_unlock_irqrestore(&ctx->timeout_lock, flags);
+-
+-	req->io_task_work.func = io_req_task_timeout;
+-	io_req_task_work_add(req);
+-	return HRTIMER_NORESTART;
+-}
+-
+-static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
+-					   __u64 user_data)
+-	__must_hold(&ctx->timeout_lock)
+-{
+-	struct io_timeout_data *io;
+-	struct io_kiocb *req;
+-	bool found = false;
+-
+-	list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
+-		found = user_data == req->user_data;
+-		if (found)
+-			break;
+-	}
+-	if (!found)
+-		return ERR_PTR(-ENOENT);
+-
+-	io = req->async_data;
+-	if (hrtimer_try_to_cancel(&io->timer) == -1)
+-		return ERR_PTR(-EALREADY);
+-	list_del_init(&req->timeout.list);
+-	return req;
+-}
+-
+-static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
+-	__must_hold(&ctx->completion_lock)
+-	__must_hold(&ctx->timeout_lock)
+-{
+-	struct io_kiocb *req = io_timeout_extract(ctx, user_data);
+-
+-	if (IS_ERR(req))
+-		return PTR_ERR(req);
+-
+-	req_set_fail(req);
+-	io_fill_cqe_req(req, -ECANCELED, 0);
+-	io_put_req_deferred(req);
+-	return 0;
+-}
+-
+-static clockid_t io_timeout_get_clock(struct io_timeout_data *data)
+-{
+-	switch (data->flags & IORING_TIMEOUT_CLOCK_MASK) {
+-	case IORING_TIMEOUT_BOOTTIME:
+-		return CLOCK_BOOTTIME;
+-	case IORING_TIMEOUT_REALTIME:
+-		return CLOCK_REALTIME;
+-	default:
+-		/* can't happen, vetted at prep time */
+-		WARN_ON_ONCE(1);
+-		fallthrough;
+-	case 0:
+-		return CLOCK_MONOTONIC;
+-	}
+-}
+-
+-static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
+-				    struct timespec64 *ts, enum hrtimer_mode mode)
+-	__must_hold(&ctx->timeout_lock)
+-{
+-	struct io_timeout_data *io;
+-	struct io_kiocb *req;
+-	bool found = false;
+-
+-	list_for_each_entry(req, &ctx->ltimeout_list, timeout.list) {
+-		found = user_data == req->user_data;
+-		if (found)
+-			break;
+-	}
+-	if (!found)
+-		return -ENOENT;
+-
+-	io = req->async_data;
+-	if (hrtimer_try_to_cancel(&io->timer) == -1)
+-		return -EALREADY;
+-	hrtimer_init(&io->timer, io_timeout_get_clock(io), mode);
+-	io->timer.function = io_link_timeout_fn;
+-	hrtimer_start(&io->timer, timespec64_to_ktime(*ts), mode);
+-	return 0;
+-}
+-
+-static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
+-			     struct timespec64 *ts, enum hrtimer_mode mode)
+-	__must_hold(&ctx->timeout_lock)
+-{
+-	struct io_kiocb *req = io_timeout_extract(ctx, user_data);
+-	struct io_timeout_data *data;
+-
+-	if (IS_ERR(req))
+-		return PTR_ERR(req);
+-
+-	req->timeout.off = 0; /* noseq */
+-	data = req->async_data;
+-	list_add_tail(&req->timeout.list, &ctx->timeout_list);
+-	hrtimer_init(&data->timer, io_timeout_get_clock(data), mode);
+-	data->timer.function = io_timeout_fn;
+-	hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
+-	return 0;
+-}
+-
+-static int io_timeout_remove_prep(struct io_kiocb *req,
+-				  const struct io_uring_sqe *sqe)
+-{
+-	struct io_timeout_rem *tr = &req->timeout_rem;
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->buf_index || sqe->len || sqe->splice_fd_in)
+-		return -EINVAL;
+-
+-	tr->ltimeout = false;
+-	tr->addr = READ_ONCE(sqe->addr);
+-	tr->flags = READ_ONCE(sqe->timeout_flags);
+-	if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) {
+-		if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
+-			return -EINVAL;
+-		if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
+-			tr->ltimeout = true;
+-		if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK|IORING_TIMEOUT_ABS))
+-			return -EINVAL;
+-		if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
+-			return -EFAULT;
+-	} else if (tr->flags) {
+-		/* timeout removal doesn't support flags */
+-		return -EINVAL;
+-	}
+-
+-	return 0;
+-}
+-
+-static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
+-{
+-	return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
+-					    : HRTIMER_MODE_REL;
+-}
+-
+-/*
+- * Remove or update an existing timeout command
+- */
+-static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_timeout_rem *tr = &req->timeout_rem;
+-	struct io_ring_ctx *ctx = req->ctx;
+-	int ret;
+-
+-	if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE)) {
+-		spin_lock(&ctx->completion_lock);
+-		spin_lock_irq(&ctx->timeout_lock);
+-		ret = io_timeout_cancel(ctx, tr->addr);
+-		spin_unlock_irq(&ctx->timeout_lock);
+-		spin_unlock(&ctx->completion_lock);
+-	} else {
+-		enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags);
+-
+-		spin_lock_irq(&ctx->timeout_lock);
+-		if (tr->ltimeout)
+-			ret = io_linked_timeout_update(ctx, tr->addr, &tr->ts, mode);
+-		else
+-			ret = io_timeout_update(ctx, tr->addr, &tr->ts, mode);
+-		spin_unlock_irq(&ctx->timeout_lock);
+-	}
+-
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete_post(req, ret, 0);
+-	return 0;
+-}
+-
+-static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
+-			   bool is_timeout_link)
+-{
+-	struct io_timeout_data *data;
+-	unsigned flags;
+-	u32 off = READ_ONCE(sqe->off);
+-
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->buf_index || sqe->len != 1 ||
+-	    sqe->splice_fd_in)
+-		return -EINVAL;
+-	if (off && is_timeout_link)
+-		return -EINVAL;
+-	flags = READ_ONCE(sqe->timeout_flags);
+-	if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK))
+-		return -EINVAL;
+-	/* more than one clock specified is invalid, obviously */
+-	if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
+-		return -EINVAL;
+-
+-	INIT_LIST_HEAD(&req->timeout.list);
+-	req->timeout.off = off;
+-	if (unlikely(off && !req->ctx->off_timeout_used))
+-		req->ctx->off_timeout_used = true;
+-
+-	if (!req->async_data && io_alloc_async_data(req))
+-		return -ENOMEM;
+-
+-	data = req->async_data;
+-	data->req = req;
+-	data->flags = flags;
+-
+-	if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
+-		return -EFAULT;
+-
+-	INIT_LIST_HEAD(&req->timeout.list);
+-	data->mode = io_translate_timeout_mode(flags);
+-	hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode);
+-
+-	if (is_timeout_link) {
+-		struct io_submit_link *link = &req->ctx->submit_state.link;
+-
+-		if (!link->head)
+-			return -EINVAL;
+-		if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
+-			return -EINVAL;
+-		req->timeout.head = link->last;
+-		link->last->flags |= REQ_F_ARM_LTIMEOUT;
+-	}
+-	return 0;
+-}
+-
+-static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_timeout_data *data = req->async_data;
+-	struct list_head *entry;
+-	u32 tail, off = req->timeout.off;
+-
+-	spin_lock_irq(&ctx->timeout_lock);
+-
+-	/*
+-	 * sqe->off holds how many events that need to occur for this
+-	 * timeout event to be satisfied. If it isn't set, then this is
+-	 * a pure timeout request, sequence isn't used.
+-	 */
+-	if (io_is_timeout_noseq(req)) {
+-		entry = ctx->timeout_list.prev;
+-		goto add;
+-	}
+-
+-	tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
+-	req->timeout.target_seq = tail + off;
+-
+-	/* Update the last seq here in case io_flush_timeouts() hasn't.
+-	 * This is safe because ->completion_lock is held, and submissions
+-	 * and completions are never mixed in the same ->completion_lock section.
+-	 */
+-	ctx->cq_last_tm_flush = tail;
+-
+-	/*
+-	 * Insertion sort, ensuring the first entry in the list is always
+-	 * the one we need first.
+-	 */
+-	list_for_each_prev(entry, &ctx->timeout_list) {
+-		struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
+-						  timeout.list);
+-
+-		if (io_is_timeout_noseq(nxt))
+-			continue;
+-		/* nxt.seq is behind @tail, otherwise would've been completed */
+-		if (off >= nxt->timeout.target_seq - tail)
+-			break;
+-	}
+-add:
+-	list_add(&req->timeout.list, entry);
+-	data->timer.function = io_timeout_fn;
+-	hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
+-	spin_unlock_irq(&ctx->timeout_lock);
+-	return 0;
+-}
+-
+-struct io_cancel_data {
+-	struct io_ring_ctx *ctx;
+-	u64 user_data;
+-};
+-
+-static bool io_cancel_cb(struct io_wq_work *work, void *data)
+-{
+-	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
+-	struct io_cancel_data *cd = data;
+-
+-	return req->ctx == cd->ctx && req->user_data == cd->user_data;
+-}
+-
+-static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
+-			       struct io_ring_ctx *ctx)
+-{
+-	struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, };
+-	enum io_wq_cancel cancel_ret;
+-	int ret = 0;
+-
+-	if (!tctx || !tctx->io_wq)
+-		return -ENOENT;
+-
+-	cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false);
+-	switch (cancel_ret) {
+-	case IO_WQ_CANCEL_OK:
+-		ret = 0;
+-		break;
+-	case IO_WQ_CANCEL_RUNNING:
+-		ret = -EALREADY;
+-		break;
+-	case IO_WQ_CANCEL_NOTFOUND:
+-		ret = -ENOENT;
+-		break;
+-	}
+-
+-	return ret;
+-}
+-
+-static int io_try_cancel_userdata(struct io_kiocb *req, u64 sqe_addr)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	int ret;
+-
+-	WARN_ON_ONCE(!io_wq_current_is_worker() && req->task != current);
+-
+-	ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
+-	if (ret != -ENOENT)
+-		return ret;
+-
+-	spin_lock(&ctx->completion_lock);
+-	spin_lock_irq(&ctx->timeout_lock);
+-	ret = io_timeout_cancel(ctx, sqe_addr);
+-	spin_unlock_irq(&ctx->timeout_lock);
+-	if (ret != -ENOENT)
+-		goto out;
+-	ret = io_poll_cancel(ctx, sqe_addr, false);
+-out:
+-	spin_unlock(&ctx->completion_lock);
+-	return ret;
+-}
+-
+-static int io_async_cancel_prep(struct io_kiocb *req,
+-				const struct io_uring_sqe *sqe)
+-{
+-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
+-		return -EINVAL;
+-	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags ||
+-	    sqe->splice_fd_in)
+-		return -EINVAL;
+-
+-	req->cancel.addr = READ_ONCE(sqe->addr);
+-	return 0;
+-}
+-
+-static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	u64 sqe_addr = req->cancel.addr;
+-	struct io_tctx_node *node;
+-	int ret;
+-
+-	ret = io_try_cancel_userdata(req, sqe_addr);
+-	if (ret != -ENOENT)
+-		goto done;
+-
+-	/* slow path, try all io-wq's */
+-	io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+-	ret = -ENOENT;
+-	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
+-		struct io_uring_task *tctx = node->task->io_uring;
+-
+-		ret = io_async_cancel_one(tctx, req->cancel.addr, ctx);
+-		if (ret != -ENOENT)
+-			break;
+-	}
+-	io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+-done:
+-	if (ret < 0)
+-		req_set_fail(req);
+-	io_req_complete_post(req, ret, 0);
+-	return 0;
+-}
+-
+-static int io_rsrc_update_prep(struct io_kiocb *req,
+-				const struct io_uring_sqe *sqe)
+-{
+-	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
+-		return -EINVAL;
+-	if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
+-		return -EINVAL;
+-
+-	req->rsrc_update.offset = READ_ONCE(sqe->off);
+-	req->rsrc_update.nr_args = READ_ONCE(sqe->len);
+-	if (!req->rsrc_update.nr_args)
+-		return -EINVAL;
+-	req->rsrc_update.arg = READ_ONCE(sqe->addr);
+-	return 0;
+-}
+-
+-static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_uring_rsrc_update2 up;
+-	int ret;
+-
+-	up.offset = req->rsrc_update.offset;
+-	up.data = req->rsrc_update.arg;
+-	up.nr = 0;
+-	up.tags = 0;
+-	up.resv = 0;
+-	up.resv2 = 0;
+-
+-	io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+-	ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
+-					&up, req->rsrc_update.nr_args);
+-	io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+-
+-	if (ret < 0)
+-		req_set_fail(req);
+-	__io_req_complete(req, issue_flags, ret, 0);
+-	return 0;
+-}
+-
+-static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+-{
+-	switch (req->opcode) {
+-	case IORING_OP_NOP:
+-		return 0;
+-	case IORING_OP_READV:
+-	case IORING_OP_READ_FIXED:
+-	case IORING_OP_READ:
+-		return io_read_prep(req, sqe);
+-	case IORING_OP_WRITEV:
+-	case IORING_OP_WRITE_FIXED:
+-	case IORING_OP_WRITE:
+-		return io_write_prep(req, sqe);
+-	case IORING_OP_POLL_ADD:
+-		return io_poll_add_prep(req, sqe);
+-	case IORING_OP_POLL_REMOVE:
+-		return io_poll_update_prep(req, sqe);
+-	case IORING_OP_FSYNC:
+-		return io_fsync_prep(req, sqe);
+-	case IORING_OP_SYNC_FILE_RANGE:
+-		return io_sfr_prep(req, sqe);
+-	case IORING_OP_SENDMSG:
+-	case IORING_OP_SEND:
+-		return io_sendmsg_prep(req, sqe);
+-	case IORING_OP_RECVMSG:
+-	case IORING_OP_RECV:
+-		return io_recvmsg_prep(req, sqe);
+-	case IORING_OP_CONNECT:
+-		return io_connect_prep(req, sqe);
+-	case IORING_OP_TIMEOUT:
+-		return io_timeout_prep(req, sqe, false);
+-	case IORING_OP_TIMEOUT_REMOVE:
+-		return io_timeout_remove_prep(req, sqe);
+-	case IORING_OP_ASYNC_CANCEL:
+-		return io_async_cancel_prep(req, sqe);
+-	case IORING_OP_LINK_TIMEOUT:
+-		return io_timeout_prep(req, sqe, true);
+-	case IORING_OP_ACCEPT:
+-		return io_accept_prep(req, sqe);
+-	case IORING_OP_FALLOCATE:
+-		return io_fallocate_prep(req, sqe);
+-	case IORING_OP_OPENAT:
+-		return io_openat_prep(req, sqe);
+-	case IORING_OP_CLOSE:
+-		return io_close_prep(req, sqe);
+-	case IORING_OP_FILES_UPDATE:
+-		return io_rsrc_update_prep(req, sqe);
+-	case IORING_OP_STATX:
+-		return io_statx_prep(req, sqe);
+-	case IORING_OP_FADVISE:
+-		return io_fadvise_prep(req, sqe);
+-	case IORING_OP_MADVISE:
+-		return io_madvise_prep(req, sqe);
+-	case IORING_OP_OPENAT2:
+-		return io_openat2_prep(req, sqe);
+-	case IORING_OP_EPOLL_CTL:
+-		return io_epoll_ctl_prep(req, sqe);
+-	case IORING_OP_SPLICE:
+-		return io_splice_prep(req, sqe);
+-	case IORING_OP_PROVIDE_BUFFERS:
+-		return io_provide_buffers_prep(req, sqe);
+-	case IORING_OP_REMOVE_BUFFERS:
+-		return io_remove_buffers_prep(req, sqe);
+-	case IORING_OP_TEE:
+-		return io_tee_prep(req, sqe);
+-	case IORING_OP_SHUTDOWN:
+-		return io_shutdown_prep(req, sqe);
+-	case IORING_OP_RENAMEAT:
+-		return io_renameat_prep(req, sqe);
+-	case IORING_OP_UNLINKAT:
+-		return io_unlinkat_prep(req, sqe);
+-	case IORING_OP_MKDIRAT:
+-		return io_mkdirat_prep(req, sqe);
+-	case IORING_OP_SYMLINKAT:
+-		return io_symlinkat_prep(req, sqe);
+-	case IORING_OP_LINKAT:
+-		return io_linkat_prep(req, sqe);
+-	}
+-
+-	printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
+-			req->opcode);
+-	return -EINVAL;
+-}
+-
+-static int io_req_prep_async(struct io_kiocb *req)
+-{
+-	if (!io_op_defs[req->opcode].needs_async_setup)
+-		return 0;
+-	if (WARN_ON_ONCE(req->async_data))
+-		return -EFAULT;
+-	if (io_alloc_async_data(req))
+-		return -EAGAIN;
+-
+-	switch (req->opcode) {
+-	case IORING_OP_READV:
+-		return io_rw_prep_async(req, READ);
+-	case IORING_OP_WRITEV:
+-		return io_rw_prep_async(req, WRITE);
+-	case IORING_OP_SENDMSG:
+-		return io_sendmsg_prep_async(req);
+-	case IORING_OP_RECVMSG:
+-		return io_recvmsg_prep_async(req);
+-	case IORING_OP_CONNECT:
+-		return io_connect_prep_async(req);
+-	}
+-	printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n",
+-		    req->opcode);
+-	return -EFAULT;
+-}
+-
+-static u32 io_get_sequence(struct io_kiocb *req)
+-{
+-	u32 seq = req->ctx->cached_sq_head;
+-
+-	/* need original cached_sq_head, but it was increased for each req */
+-	io_for_each_link(req, req)
+-		seq--;
+-	return seq;
+-}
+-
+-static bool io_drain_req(struct io_kiocb *req)
+-{
+-	struct io_kiocb *pos;
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_defer_entry *de;
+-	int ret;
+-	u32 seq;
+-
+-	if (req->flags & REQ_F_FAIL) {
+-		io_req_complete_fail_submit(req);
+-		return true;
+-	}
+-
+-	/*
+-	 * If we need to drain a request in the middle of a link, drain the
+-	 * head request and the next request/link after the current link.
+-	 * Considering sequential execution of links, IOSQE_IO_DRAIN will be
+-	 * maintained for every request of our link.
+-	 */
+-	if (ctx->drain_next) {
+-		req->flags |= REQ_F_IO_DRAIN;
+-		ctx->drain_next = false;
+-	}
+-	/* not interested in head, start from the first linked */
+-	io_for_each_link(pos, req->link) {
+-		if (pos->flags & REQ_F_IO_DRAIN) {
+-			ctx->drain_next = true;
+-			req->flags |= REQ_F_IO_DRAIN;
+-			break;
+-		}
+-	}
+-
+-	/* Still need defer if there is pending req in defer list. */
+-	spin_lock(&ctx->completion_lock);
+-	if (likely(list_empty_careful(&ctx->defer_list) &&
+-		!(req->flags & REQ_F_IO_DRAIN))) {
+-		spin_unlock(&ctx->completion_lock);
+-		ctx->drain_active = false;
+-		return false;
+-	}
+-	spin_unlock(&ctx->completion_lock);
+-
+-	seq = io_get_sequence(req);
+-	/* Still a chance to pass the sequence check */
+-	if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
+-		return false;
+-
+-	ret = io_req_prep_async(req);
+-	if (ret)
+-		goto fail;
+-	io_prep_async_link(req);
+-	de = kmalloc(sizeof(*de), GFP_KERNEL);
+-	if (!de) {
+-		ret = -ENOMEM;
+-fail:
+-		io_req_complete_failed(req, ret);
+-		return true;
+-	}
+-
+-	spin_lock(&ctx->completion_lock);
+-	if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
+-		spin_unlock(&ctx->completion_lock);
+-		kfree(de);
+-		io_queue_async_work(req, NULL);
+-		return true;
+-	}
+-
+-	trace_io_uring_defer(ctx, req, req->user_data);
+-	de->req = req;
+-	de->seq = seq;
+-	list_add_tail(&de->list, &ctx->defer_list);
+-	spin_unlock(&ctx->completion_lock);
+-	return true;
+-}
+-
+-static void io_clean_op(struct io_kiocb *req)
+-{
+-	if (req->flags & REQ_F_BUFFER_SELECTED) {
+-		switch (req->opcode) {
+-		case IORING_OP_READV:
+-		case IORING_OP_READ_FIXED:
+-		case IORING_OP_READ:
+-			kfree((void *)(unsigned long)req->rw.addr);
+-			break;
+-		case IORING_OP_RECVMSG:
+-		case IORING_OP_RECV:
+-			kfree(req->sr_msg.kbuf);
+-			break;
+-		}
+-	}
+-
+-	if (req->flags & REQ_F_NEED_CLEANUP) {
+-		switch (req->opcode) {
+-		case IORING_OP_READV:
+-		case IORING_OP_READ_FIXED:
+-		case IORING_OP_READ:
+-		case IORING_OP_WRITEV:
+-		case IORING_OP_WRITE_FIXED:
+-		case IORING_OP_WRITE: {
+-			struct io_async_rw *io = req->async_data;
+-
+-			kfree(io->free_iovec);
+-			break;
+-			}
+-		case IORING_OP_RECVMSG:
+-		case IORING_OP_SENDMSG: {
+-			struct io_async_msghdr *io = req->async_data;
+-
+-			kfree(io->free_iov);
+-			break;
+-			}
+-		case IORING_OP_OPENAT:
+-		case IORING_OP_OPENAT2:
+-			if (req->open.filename)
+-				putname(req->open.filename);
+-			break;
+-		case IORING_OP_RENAMEAT:
+-			putname(req->rename.oldpath);
+-			putname(req->rename.newpath);
+-			break;
+-		case IORING_OP_UNLINKAT:
+-			putname(req->unlink.filename);
+-			break;
+-		case IORING_OP_MKDIRAT:
+-			putname(req->mkdir.filename);
+-			break;
+-		case IORING_OP_SYMLINKAT:
+-			putname(req->symlink.oldpath);
+-			putname(req->symlink.newpath);
+-			break;
+-		case IORING_OP_LINKAT:
+-			putname(req->hardlink.oldpath);
+-			putname(req->hardlink.newpath);
+-			break;
+-		}
+-	}
+-	if ((req->flags & REQ_F_POLLED) && req->apoll) {
+-		kfree(req->apoll->double_poll);
+-		kfree(req->apoll);
+-		req->apoll = NULL;
+-	}
+-	if (req->flags & REQ_F_INFLIGHT) {
+-		struct io_uring_task *tctx = req->task->io_uring;
+-
+-		atomic_dec(&tctx->inflight_tracked);
+-	}
+-	if (req->flags & REQ_F_CREDS)
+-		put_cred(req->creds);
+-
+-	req->flags &= ~IO_REQ_CLEAN_FLAGS;
+-}
+-
+-static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	const struct cred *creds = NULL;
+-	int ret;
+-
+-	if ((req->flags & REQ_F_CREDS) && req->creds != current_cred())
+-		creds = override_creds(req->creds);
+-
+-	switch (req->opcode) {
+-	case IORING_OP_NOP:
+-		ret = io_nop(req, issue_flags);
+-		break;
+-	case IORING_OP_READV:
+-	case IORING_OP_READ_FIXED:
+-	case IORING_OP_READ:
+-		ret = io_read(req, issue_flags);
+-		break;
+-	case IORING_OP_WRITEV:
+-	case IORING_OP_WRITE_FIXED:
+-	case IORING_OP_WRITE:
+-		ret = io_write(req, issue_flags);
+-		break;
+-	case IORING_OP_FSYNC:
+-		ret = io_fsync(req, issue_flags);
+-		break;
+-	case IORING_OP_POLL_ADD:
+-		ret = io_poll_add(req, issue_flags);
+-		break;
+-	case IORING_OP_POLL_REMOVE:
+-		ret = io_poll_update(req, issue_flags);
+-		break;
+-	case IORING_OP_SYNC_FILE_RANGE:
+-		ret = io_sync_file_range(req, issue_flags);
+-		break;
+-	case IORING_OP_SENDMSG:
+-		ret = io_sendmsg(req, issue_flags);
+-		break;
+-	case IORING_OP_SEND:
+-		ret = io_send(req, issue_flags);
+-		break;
+-	case IORING_OP_RECVMSG:
+-		ret = io_recvmsg(req, issue_flags);
+-		break;
+-	case IORING_OP_RECV:
+-		ret = io_recv(req, issue_flags);
+-		break;
+-	case IORING_OP_TIMEOUT:
+-		ret = io_timeout(req, issue_flags);
+-		break;
+-	case IORING_OP_TIMEOUT_REMOVE:
+-		ret = io_timeout_remove(req, issue_flags);
+-		break;
+-	case IORING_OP_ACCEPT:
+-		ret = io_accept(req, issue_flags);
+-		break;
+-	case IORING_OP_CONNECT:
+-		ret = io_connect(req, issue_flags);
+-		break;
+-	case IORING_OP_ASYNC_CANCEL:
+-		ret = io_async_cancel(req, issue_flags);
+-		break;
+-	case IORING_OP_FALLOCATE:
+-		ret = io_fallocate(req, issue_flags);
+-		break;
+-	case IORING_OP_OPENAT:
+-		ret = io_openat(req, issue_flags);
+-		break;
+-	case IORING_OP_CLOSE:
+-		ret = io_close(req, issue_flags);
+-		break;
+-	case IORING_OP_FILES_UPDATE:
+-		ret = io_files_update(req, issue_flags);
+-		break;
+-	case IORING_OP_STATX:
+-		ret = io_statx(req, issue_flags);
+-		break;
+-	case IORING_OP_FADVISE:
+-		ret = io_fadvise(req, issue_flags);
+-		break;
+-	case IORING_OP_MADVISE:
+-		ret = io_madvise(req, issue_flags);
+-		break;
+-	case IORING_OP_OPENAT2:
+-		ret = io_openat2(req, issue_flags);
+-		break;
+-	case IORING_OP_EPOLL_CTL:
+-		ret = io_epoll_ctl(req, issue_flags);
+-		break;
+-	case IORING_OP_SPLICE:
+-		ret = io_splice(req, issue_flags);
+-		break;
+-	case IORING_OP_PROVIDE_BUFFERS:
+-		ret = io_provide_buffers(req, issue_flags);
+-		break;
+-	case IORING_OP_REMOVE_BUFFERS:
+-		ret = io_remove_buffers(req, issue_flags);
+-		break;
+-	case IORING_OP_TEE:
+-		ret = io_tee(req, issue_flags);
+-		break;
+-	case IORING_OP_SHUTDOWN:
+-		ret = io_shutdown(req, issue_flags);
+-		break;
+-	case IORING_OP_RENAMEAT:
+-		ret = io_renameat(req, issue_flags);
+-		break;
+-	case IORING_OP_UNLINKAT:
+-		ret = io_unlinkat(req, issue_flags);
+-		break;
+-	case IORING_OP_MKDIRAT:
+-		ret = io_mkdirat(req, issue_flags);
+-		break;
+-	case IORING_OP_SYMLINKAT:
+-		ret = io_symlinkat(req, issue_flags);
+-		break;
+-	case IORING_OP_LINKAT:
+-		ret = io_linkat(req, issue_flags);
+-		break;
+-	default:
+-		ret = -EINVAL;
+-		break;
+-	}
+-
+-	if (creds)
+-		revert_creds(creds);
+-	if (ret)
+-		return ret;
+-	/* If the op doesn't have a file, we're not polling for it */
+-	if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file)
+-		io_iopoll_req_issued(req);
+-
+-	return 0;
+-}
+-
+-static struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
+-{
+-	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
+-
+-	req = io_put_req_find_next(req);
+-	return req ? &req->work : NULL;
+-}
+-
+-static void io_wq_submit_work(struct io_wq_work *work)
+-{
+-	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
+-	struct io_kiocb *timeout;
+-	int ret = 0;
+-
+-	/* one will be dropped by ->io_free_work() after returning to io-wq */
+-	if (!(req->flags & REQ_F_REFCOUNT))
+-		__io_req_set_refcount(req, 2);
+-	else
+-		req_ref_get(req);
+-
+-	timeout = io_prep_linked_timeout(req);
+-	if (timeout)
+-		io_queue_linked_timeout(timeout);
+-
+-	/* either cancelled or io-wq is dying, so don't touch tctx->iowq */
+-	if (work->flags & IO_WQ_WORK_CANCEL)
+-		ret = -ECANCELED;
+-
+-	if (!ret) {
+-		do {
+-			ret = io_issue_sqe(req, 0);
+-			/*
+-			 * We can get EAGAIN for polled IO even though we're
+-			 * forcing a sync submission from here, since we can't
+-			 * wait for request slots on the block side.
+-			 */
+-			if (ret != -EAGAIN || !(req->ctx->flags & IORING_SETUP_IOPOLL))
+-				break;
+-			cond_resched();
+-		} while (1);
+-	}
+-
+-	/* avoid locking problems by failing it from a clean context */
+-	if (ret)
+-		io_req_task_queue_fail(req, ret);
+-}
+-
+-static inline struct io_fixed_file *io_fixed_file_slot(struct io_file_table *table,
+-						       unsigned i)
+-{
+-	return &table->files[i];
+-}
+-
+-static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
+-					      int index)
+-{
+-	struct io_fixed_file *slot = io_fixed_file_slot(&ctx->file_table, index);
+-
+-	return (struct file *) (slot->file_ptr & FFS_MASK);
+-}
+-
+-static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file)
+-{
+-	unsigned long file_ptr = (unsigned long) file;
+-
+-	if (__io_file_supports_nowait(file, READ))
+-		file_ptr |= FFS_ASYNC_READ;
+-	if (__io_file_supports_nowait(file, WRITE))
+-		file_ptr |= FFS_ASYNC_WRITE;
+-	if (S_ISREG(file_inode(file)->i_mode))
+-		file_ptr |= FFS_ISREG;
+-	file_slot->file_ptr = file_ptr;
+-}
+-
+-static inline struct file *io_file_get_fixed(struct io_ring_ctx *ctx,
+-					     struct io_kiocb *req, int fd)
+-{
+-	struct file *file;
+-	unsigned long file_ptr;
+-
+-	if (unlikely((unsigned int)fd >= ctx->nr_user_files))
+-		return NULL;
+-	fd = array_index_nospec(fd, ctx->nr_user_files);
+-	file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr;
+-	file = (struct file *) (file_ptr & FFS_MASK);
+-	file_ptr &= ~FFS_MASK;
+-	/* mask in overlapping REQ_F and FFS bits */
+-	req->flags |= (file_ptr << REQ_F_NOWAIT_READ_BIT);
+-	io_req_set_rsrc_node(req);
+-	return file;
+-}
+-
+-static struct file *io_file_get_normal(struct io_ring_ctx *ctx,
+-				       struct io_kiocb *req, int fd)
+-{
+-	struct file *file = fget(fd);
+-
+-	trace_io_uring_file_get(ctx, fd);
+-
+-	/* we don't allow fixed io_uring files */
+-	if (file && unlikely(file->f_op == &io_uring_fops))
+-		io_req_track_inflight(req);
+-	return file;
+-}
+-
+-static inline struct file *io_file_get(struct io_ring_ctx *ctx,
+-				       struct io_kiocb *req, int fd, bool fixed)
+-{
+-	if (fixed)
+-		return io_file_get_fixed(ctx, req, fd);
+-	else
+-		return io_file_get_normal(ctx, req, fd);
+-}
+-
+-static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked)
+-{
+-	struct io_kiocb *prev = req->timeout.prev;
+-	int ret = -ENOENT;
+-
+-	if (prev) {
+-		if (!(req->task->flags & PF_EXITING))
+-			ret = io_try_cancel_userdata(req, prev->user_data);
+-		io_req_complete_post(req, ret ?: -ETIME, 0);
+-		io_put_req(prev);
+-	} else {
+-		io_req_complete_post(req, -ETIME, 0);
+-	}
+-}
+-
+-static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
+-{
+-	struct io_timeout_data *data = container_of(timer,
+-						struct io_timeout_data, timer);
+-	struct io_kiocb *prev, *req = data->req;
+-	struct io_ring_ctx *ctx = req->ctx;
+-	unsigned long flags;
+-
+-	spin_lock_irqsave(&ctx->timeout_lock, flags);
+-	prev = req->timeout.head;
+-	req->timeout.head = NULL;
+-
+-	/*
+-	 * We don't expect the list to be empty, that will only happen if we
+-	 * race with the completion of the linked work.
+-	 */
+-	if (prev) {
+-		io_remove_next_linked(prev);
+-		if (!req_ref_inc_not_zero(prev))
+-			prev = NULL;
+-	}
+-	list_del(&req->timeout.list);
+-	req->timeout.prev = prev;
+-	spin_unlock_irqrestore(&ctx->timeout_lock, flags);
+-
+-	req->io_task_work.func = io_req_task_link_timeout;
+-	io_req_task_work_add(req);
+-	return HRTIMER_NORESTART;
+-}
+-
+-static void io_queue_linked_timeout(struct io_kiocb *req)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-
+-	spin_lock_irq(&ctx->timeout_lock);
+-	/*
+-	 * If the back reference is NULL, then our linked request finished
+-	 * before we got a chance to setup the timer
+-	 */
+-	if (req->timeout.head) {
+-		struct io_timeout_data *data = req->async_data;
+-
+-		data->timer.function = io_link_timeout_fn;
+-		hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
+-				data->mode);
+-		list_add_tail(&req->timeout.list, &ctx->ltimeout_list);
+-	}
+-	spin_unlock_irq(&ctx->timeout_lock);
+-	/* drop submission reference */
+-	io_put_req(req);
+-}
+-
+-static void __io_queue_sqe(struct io_kiocb *req)
+-	__must_hold(&req->ctx->uring_lock)
+-{
+-	struct io_kiocb *linked_timeout;
+-	int ret;
+-
+-issue_sqe:
+-	ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
+-
+-	/*
+-	 * We async punt it if the file wasn't marked NOWAIT, or if the file
+-	 * doesn't support non-blocking read/write attempts
+-	 */
+-	if (likely(!ret)) {
+-		if (req->flags & REQ_F_COMPLETE_INLINE) {
+-			struct io_ring_ctx *ctx = req->ctx;
+-			struct io_submit_state *state = &ctx->submit_state;
+-
+-			state->compl_reqs[state->compl_nr++] = req;
+-			if (state->compl_nr == ARRAY_SIZE(state->compl_reqs))
+-				io_submit_flush_completions(ctx);
+-			return;
+-		}
+-
+-		linked_timeout = io_prep_linked_timeout(req);
+-		if (linked_timeout)
+-			io_queue_linked_timeout(linked_timeout);
+-	} else if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
+-		linked_timeout = io_prep_linked_timeout(req);
+-
+-		switch (io_arm_poll_handler(req)) {
+-		case IO_APOLL_READY:
+-			if (linked_timeout)
+-				io_queue_linked_timeout(linked_timeout);
+-			goto issue_sqe;
+-		case IO_APOLL_ABORTED:
+-			/*
+-			 * Queued up for async execution, worker will release
+-			 * submit reference when the iocb is actually submitted.
+-			 */
+-			io_queue_async_work(req, NULL);
+-			break;
+-		}
+-
+-		if (linked_timeout)
+-			io_queue_linked_timeout(linked_timeout);
+-	} else {
+-		io_req_complete_failed(req, ret);
+-	}
+-}
+-
+-static inline void io_queue_sqe(struct io_kiocb *req)
+-	__must_hold(&req->ctx->uring_lock)
+-{
+-	if (unlikely(req->ctx->drain_active) && io_drain_req(req))
+-		return;
+-
+-	if (likely(!(req->flags & (REQ_F_FORCE_ASYNC | REQ_F_FAIL)))) {
+-		__io_queue_sqe(req);
+-	} else if (req->flags & REQ_F_FAIL) {
+-		io_req_complete_fail_submit(req);
+-	} else {
+-		int ret = io_req_prep_async(req);
+-
+-		if (unlikely(ret))
+-			io_req_complete_failed(req, ret);
+-		else
+-			io_queue_async_work(req, NULL);
+-	}
+-}
+-
+-/*
+- * Check SQE restrictions (opcode and flags).
+- *
+- * Returns 'true' if SQE is allowed, 'false' otherwise.
+- */
+-static inline bool io_check_restriction(struct io_ring_ctx *ctx,
+-					struct io_kiocb *req,
+-					unsigned int sqe_flags)
+-{
+-	if (likely(!ctx->restricted))
+-		return true;
+-
+-	if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
+-		return false;
+-
+-	if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
+-	    ctx->restrictions.sqe_flags_required)
+-		return false;
+-
+-	if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
+-			  ctx->restrictions.sqe_flags_required))
+-		return false;
+-
+-	return true;
+-}
+-
+-static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
+-		       const struct io_uring_sqe *sqe)
+-	__must_hold(&ctx->uring_lock)
+-{
+-	struct io_submit_state *state;
+-	unsigned int sqe_flags;
+-	int personality, ret = 0;
+-
+-	/* req is partially pre-initialised, see io_preinit_req() */
+-	req->opcode = READ_ONCE(sqe->opcode);
+-	/* same numerical values with corresponding REQ_F_*, safe to copy */
+-	req->flags = sqe_flags = READ_ONCE(sqe->flags);
+-	req->user_data = READ_ONCE(sqe->user_data);
+-	req->file = NULL;
+-	req->fixed_rsrc_refs = NULL;
+-	req->task = current;
+-
+-	/* enforce forwards compatibility on users */
+-	if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))
+-		return -EINVAL;
+-	if (unlikely(req->opcode >= IORING_OP_LAST))
+-		return -EINVAL;
+-	if (!io_check_restriction(ctx, req, sqe_flags))
+-		return -EACCES;
+-
+-	if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
+-	    !io_op_defs[req->opcode].buffer_select)
+-		return -EOPNOTSUPP;
+-	if (unlikely(sqe_flags & IOSQE_IO_DRAIN))
+-		ctx->drain_active = true;
+-
+-	personality = READ_ONCE(sqe->personality);
+-	if (personality) {
+-		req->creds = xa_load(&ctx->personalities, personality);
+-		if (!req->creds)
+-			return -EINVAL;
+-		get_cred(req->creds);
+-		req->flags |= REQ_F_CREDS;
+-	}
+-	state = &ctx->submit_state;
+-
+-	/*
+-	 * Plug now if we have more than 1 IO left after this, and the target
+-	 * is potentially a read/write to block based storage.
+-	 */
+-	if (!state->plug_started && state->ios_left > 1 &&
+-	    io_op_defs[req->opcode].plug) {
+-		blk_start_plug(&state->plug);
+-		state->plug_started = true;
+-	}
+-
+-	if (io_op_defs[req->opcode].needs_file) {
+-		req->file = io_file_get(ctx, req, READ_ONCE(sqe->fd),
+-					(sqe_flags & IOSQE_FIXED_FILE));
+-		if (unlikely(!req->file))
+-			ret = -EBADF;
+-	}
+-
+-	state->ios_left--;
+-	return ret;
+-}
+-
+-static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
+-			 const struct io_uring_sqe *sqe)
+-	__must_hold(&ctx->uring_lock)
+-{
+-	struct io_submit_link *link = &ctx->submit_state.link;
+-	int ret;
+-
+-	ret = io_init_req(ctx, req, sqe);
+-	if (unlikely(ret)) {
+-fail_req:
+-		/* fail even hard links since we don't submit */
+-		if (link->head) {
+-			/*
+-			 * we can judge a link req is failed or cancelled by if
+-			 * REQ_F_FAIL is set, but the head is an exception since
+-			 * it may be set REQ_F_FAIL because of other req's failure
+-			 * so let's leverage req->result to distinguish if a head
+-			 * is set REQ_F_FAIL because of its failure or other req's
+-			 * failure so that we can set the correct ret code for it.
+-			 * init result here to avoid affecting the normal path.
+-			 */
+-			if (!(link->head->flags & REQ_F_FAIL))
+-				req_fail_link_node(link->head, -ECANCELED);
+-		} else if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
+-			/*
+-			 * the current req is a normal req, we should return
+-			 * error and thus break the submittion loop.
+-			 */
+-			io_req_complete_failed(req, ret);
+-			return ret;
+-		}
+-		req_fail_link_node(req, ret);
+-	} else {
+-		ret = io_req_prep(req, sqe);
+-		if (unlikely(ret))
+-			goto fail_req;
+-	}
+-
+-	/* don't need @sqe from now on */
+-	trace_io_uring_submit_sqe(ctx, req, req->opcode, req->user_data,
+-				  req->flags, true,
+-				  ctx->flags & IORING_SETUP_SQPOLL);
+-
+-	/*
+-	 * If we already have a head request, queue this one for async
+-	 * submittal once the head completes. If we don't have a head but
+-	 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
+-	 * submitted sync once the chain is complete. If none of those
+-	 * conditions are true (normal request), then just queue it.
+-	 */
+-	if (link->head) {
+-		struct io_kiocb *head = link->head;
+-
+-		if (!(req->flags & REQ_F_FAIL)) {
+-			ret = io_req_prep_async(req);
+-			if (unlikely(ret)) {
+-				req_fail_link_node(req, ret);
+-				if (!(head->flags & REQ_F_FAIL))
+-					req_fail_link_node(head, -ECANCELED);
+-			}
+-		}
+-		trace_io_uring_link(ctx, req, head);
+-		link->last->link = req;
+-		link->last = req;
+-
+-		/* last request of a link, enqueue the link */
+-		if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
+-			link->head = NULL;
+-			io_queue_sqe(head);
+-		}
+-	} else {
+-		if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
+-			link->head = req;
+-			link->last = req;
+-		} else {
+-			io_queue_sqe(req);
+-		}
+-	}
+-
+-	return 0;
+-}
+-
+-/*
+- * Batched submission is done, ensure local IO is flushed out.
+- */
+-static void io_submit_state_end(struct io_submit_state *state,
+-				struct io_ring_ctx *ctx)
+-{
+-	if (state->link.head)
+-		io_queue_sqe(state->link.head);
+-	if (state->compl_nr)
+-		io_submit_flush_completions(ctx);
+-	if (state->plug_started)
+-		blk_finish_plug(&state->plug);
+-}
+-
+-/*
+- * Start submission side cache.
+- */
+-static void io_submit_state_start(struct io_submit_state *state,
+-				  unsigned int max_ios)
+-{
+-	state->plug_started = false;
+-	state->ios_left = max_ios;
+-	/* set only head, no need to init link_last in advance */
+-	state->link.head = NULL;
+-}
+-
+-static void io_commit_sqring(struct io_ring_ctx *ctx)
+-{
+-	struct io_rings *rings = ctx->rings;
+-
+-	/*
+-	 * Ensure any loads from the SQEs are done at this point,
+-	 * since once we write the new head, the application could
+-	 * write new data to them.
+-	 */
+-	smp_store_release(&rings->sq.head, ctx->cached_sq_head);
+-}
+-
+-/*
+- * Fetch an sqe, if one is available. Note this returns a pointer to memory
+- * that is mapped by userspace. This means that care needs to be taken to
+- * ensure that reads are stable, as we cannot rely on userspace always
+- * being a good citizen. If members of the sqe are validated and then later
+- * used, it's important that those reads are done through READ_ONCE() to
+- * prevent a re-load down the line.
+- */
+-static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
+-{
+-	unsigned head, mask = ctx->sq_entries - 1;
+-	unsigned sq_idx = ctx->cached_sq_head++ & mask;
+-
+-	/*
+-	 * The cached sq head (or cq tail) serves two purposes:
+-	 *
+-	 * 1) allows us to batch the cost of updating the user visible
+-	 *    head updates.
+-	 * 2) allows the kernel side to track the head on its own, even
+-	 *    though the application is the one updating it.
+-	 */
+-	head = READ_ONCE(ctx->sq_array[sq_idx]);
+-	if (likely(head < ctx->sq_entries))
+-		return &ctx->sq_sqes[head];
+-
+-	/* drop invalid entries */
+-	ctx->cq_extra--;
+-	WRITE_ONCE(ctx->rings->sq_dropped,
+-		   READ_ONCE(ctx->rings->sq_dropped) + 1);
+-	return NULL;
+-}
+-
+-static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
+-	__must_hold(&ctx->uring_lock)
+-{
+-	int submitted = 0;
+-
+-	/* make sure SQ entry isn't read before tail */
+-	nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
+-	if (!percpu_ref_tryget_many(&ctx->refs, nr))
+-		return -EAGAIN;
+-	io_get_task_refs(nr);
+-
+-	io_submit_state_start(&ctx->submit_state, nr);
+-	while (submitted < nr) {
+-		const struct io_uring_sqe *sqe;
+-		struct io_kiocb *req;
+-
+-		req = io_alloc_req(ctx);
+-		if (unlikely(!req)) {
+-			if (!submitted)
+-				submitted = -EAGAIN;
+-			break;
+-		}
+-		sqe = io_get_sqe(ctx);
+-		if (unlikely(!sqe)) {
+-			list_add(&req->inflight_entry, &ctx->submit_state.free_list);
+-			break;
+-		}
+-		/* will complete beyond this point, count as submitted */
+-		submitted++;
+-		if (io_submit_sqe(ctx, req, sqe))
+-			break;
+-	}
+-
+-	if (unlikely(submitted != nr)) {
+-		int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
+-		int unused = nr - ref_used;
+-
+-		current->io_uring->cached_refs += unused;
+-		percpu_ref_put_many(&ctx->refs, unused);
+-	}
+-
+-	io_submit_state_end(&ctx->submit_state, ctx);
+-	 /* Commit SQ ring head once we've consumed and submitted all SQEs */
+-	io_commit_sqring(ctx);
+-
+-	return submitted;
+-}
+-
+-static inline bool io_sqd_events_pending(struct io_sq_data *sqd)
+-{
+-	return READ_ONCE(sqd->state);
+-}
+-
+-static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
+-{
+-	/* Tell userspace we may need a wakeup call */
+-	spin_lock(&ctx->completion_lock);
+-	WRITE_ONCE(ctx->rings->sq_flags,
+-		   ctx->rings->sq_flags | IORING_SQ_NEED_WAKEUP);
+-	spin_unlock(&ctx->completion_lock);
+-}
+-
+-static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
+-{
+-	spin_lock(&ctx->completion_lock);
+-	WRITE_ONCE(ctx->rings->sq_flags,
+-		   ctx->rings->sq_flags & ~IORING_SQ_NEED_WAKEUP);
+-	spin_unlock(&ctx->completion_lock);
+-}
+-
+-static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
+-{
+-	unsigned int to_submit;
+-	int ret = 0;
+-
+-	to_submit = io_sqring_entries(ctx);
+-	/* if we're handling multiple rings, cap submit size for fairness */
+-	if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE)
+-		to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;
+-
+-	if (!list_empty(&ctx->iopoll_list) || to_submit) {
+-		unsigned nr_events = 0;
+-		const struct cred *creds = NULL;
+-
+-		if (ctx->sq_creds != current_cred())
+-			creds = override_creds(ctx->sq_creds);
+-
+-		mutex_lock(&ctx->uring_lock);
+-		if (!list_empty(&ctx->iopoll_list))
+-			io_do_iopoll(ctx, &nr_events, 0);
+-
+-		/*
+-		 * Don't submit if refs are dying, good for io_uring_register(),
+-		 * but also it is relied upon by io_ring_exit_work()
+-		 */
+-		if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
+-		    !(ctx->flags & IORING_SETUP_R_DISABLED))
+-			ret = io_submit_sqes(ctx, to_submit);
+-		mutex_unlock(&ctx->uring_lock);
+-
+-		if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
+-			wake_up(&ctx->sqo_sq_wait);
+-		if (creds)
+-			revert_creds(creds);
+-	}
+-
+-	return ret;
+-}
+-
+-static void io_sqd_update_thread_idle(struct io_sq_data *sqd)
+-{
+-	struct io_ring_ctx *ctx;
+-	unsigned sq_thread_idle = 0;
+-
+-	list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
+-		sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle);
+-	sqd->sq_thread_idle = sq_thread_idle;
+-}
+-
+-static bool io_sqd_handle_event(struct io_sq_data *sqd)
+-{
+-	bool did_sig = false;
+-	struct ksignal ksig;
+-
+-	if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
+-	    signal_pending(current)) {
+-		mutex_unlock(&sqd->lock);
+-		if (signal_pending(current))
+-			did_sig = get_signal(&ksig);
+-		cond_resched();
+-		mutex_lock(&sqd->lock);
+-	}
+-	return did_sig || test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
+-}
+-
+-static int io_sq_thread(void *data)
+-{
+-	struct io_sq_data *sqd = data;
+-	struct io_ring_ctx *ctx;
+-	unsigned long timeout = 0;
+-	char buf[TASK_COMM_LEN];
+-	DEFINE_WAIT(wait);
+-
+-	snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
+-	set_task_comm(current, buf);
+-
+-	if (sqd->sq_cpu != -1)
+-		set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
+-	else
+-		set_cpus_allowed_ptr(current, cpu_online_mask);
+-	current->flags |= PF_NO_SETAFFINITY;
+-
+-	mutex_lock(&sqd->lock);
+-	while (1) {
+-		bool cap_entries, sqt_spin = false;
+-
+-		if (io_sqd_events_pending(sqd) || signal_pending(current)) {
+-			if (io_sqd_handle_event(sqd))
+-				break;
+-			timeout = jiffies + sqd->sq_thread_idle;
+-		}
+-
+-		cap_entries = !list_is_singular(&sqd->ctx_list);
+-		list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
+-			int ret = __io_sq_thread(ctx, cap_entries);
+-
+-			if (!sqt_spin && (ret > 0 || !list_empty(&ctx->iopoll_list)))
+-				sqt_spin = true;
+-		}
+-		if (io_run_task_work())
+-			sqt_spin = true;
+-
+-		if (sqt_spin || !time_after(jiffies, timeout)) {
+-			cond_resched();
+-			if (sqt_spin)
+-				timeout = jiffies + sqd->sq_thread_idle;
+-			continue;
+-		}
+-
+-		prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
+-		if (!io_sqd_events_pending(sqd) && !current->task_works) {
+-			bool needs_sched = true;
+-
+-			list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
+-				io_ring_set_wakeup_flag(ctx);
+-
+-				if ((ctx->flags & IORING_SETUP_IOPOLL) &&
+-				    !list_empty_careful(&ctx->iopoll_list)) {
+-					needs_sched = false;
+-					break;
+-				}
+-				if (io_sqring_entries(ctx)) {
+-					needs_sched = false;
+-					break;
+-				}
+-			}
+-
+-			if (needs_sched) {
+-				mutex_unlock(&sqd->lock);
+-				schedule();
+-				mutex_lock(&sqd->lock);
+-			}
+-			list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
+-				io_ring_clear_wakeup_flag(ctx);
+-		}
+-
+-		finish_wait(&sqd->wait, &wait);
+-		timeout = jiffies + sqd->sq_thread_idle;
+-	}
+-
+-	io_uring_cancel_generic(true, sqd);
+-	sqd->thread = NULL;
+-	list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
+-		io_ring_set_wakeup_flag(ctx);
+-	io_run_task_work();
+-	mutex_unlock(&sqd->lock);
+-
+-	complete(&sqd->exited);
+-	do_exit(0);
+-}
+-
+-struct io_wait_queue {
+-	struct wait_queue_entry wq;
+-	struct io_ring_ctx *ctx;
+-	unsigned cq_tail;
+-	unsigned nr_timeouts;
+-};
+-
+-static inline bool io_should_wake(struct io_wait_queue *iowq)
+-{
+-	struct io_ring_ctx *ctx = iowq->ctx;
+-	int dist = ctx->cached_cq_tail - (int) iowq->cq_tail;
+-
+-	/*
+-	 * Wake up if we have enough events, or if a timeout occurred since we
+-	 * started waiting. For timeouts, we always want to return to userspace,
+-	 * regardless of event count.
+-	 */
+-	return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
+-}
+-
+-static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
+-			    int wake_flags, void *key)
+-{
+-	struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
+-							wq);
+-
+-	/*
+-	 * Cannot safely flush overflowed CQEs from here, ensure we wake up
+-	 * the task, and the next invocation will do it.
+-	 */
+-	if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->check_cq_overflow))
+-		return autoremove_wake_function(curr, mode, wake_flags, key);
+-	return -1;
+-}
+-
+-static int io_run_task_work_sig(void)
+-{
+-	if (io_run_task_work())
+-		return 1;
+-	if (!signal_pending(current))
+-		return 0;
+-	if (test_thread_flag(TIF_NOTIFY_SIGNAL))
+-		return -ERESTARTSYS;
+-	return -EINTR;
+-}
+-
+-/* when returns >0, the caller should retry */
+-static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
+-					  struct io_wait_queue *iowq,
+-					  ktime_t timeout)
+-{
+-	int ret;
+-
+-	/* make sure we run task_work before checking for signals */
+-	ret = io_run_task_work_sig();
+-	if (ret || io_should_wake(iowq))
+-		return ret;
+-	/* let the caller flush overflows, retry */
+-	if (test_bit(0, &ctx->check_cq_overflow))
+-		return 1;
+-
+-	if (!schedule_hrtimeout(&timeout, HRTIMER_MODE_ABS))
+-		return -ETIME;
+-	return 1;
+-}
+-
+-/*
+- * Wait until events become available, if we don't already have some. The
+- * application must reap them itself, as they reside on the shared cq ring.
+- */
+-static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
+-			  const sigset_t __user *sig, size_t sigsz,
+-			  struct __kernel_timespec __user *uts)
+-{
+-	struct io_wait_queue iowq;
+-	struct io_rings *rings = ctx->rings;
+-	ktime_t timeout = KTIME_MAX;
+-	int ret;
+-
+-	do {
+-		io_cqring_overflow_flush(ctx);
+-		if (io_cqring_events(ctx) >= min_events)
+-			return 0;
+-		if (!io_run_task_work())
+-			break;
+-	} while (1);
+-
+-	if (uts) {
+-		struct timespec64 ts;
+-
+-		if (get_timespec64(&ts, uts))
+-			return -EFAULT;
+-		timeout = ktime_add_ns(timespec64_to_ktime(ts), ktime_get_ns());
+-	}
+-
+-	if (sig) {
+-#ifdef CONFIG_COMPAT
+-		if (in_compat_syscall())
+-			ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
+-						      sigsz);
+-		else
+-#endif
+-			ret = set_user_sigmask(sig, sigsz);
+-
+-		if (ret)
+-			return ret;
+-	}
+-
+-	init_waitqueue_func_entry(&iowq.wq, io_wake_function);
+-	iowq.wq.private = current;
+-	INIT_LIST_HEAD(&iowq.wq.entry);
+-	iowq.ctx = ctx;
+-	iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
+-	iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events;
+-
+-	trace_io_uring_cqring_wait(ctx, min_events);
+-	do {
+-		/* if we can't even flush overflow, don't wait for more */
+-		if (!io_cqring_overflow_flush(ctx)) {
+-			ret = -EBUSY;
+-			break;
+-		}
+-		prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq,
+-						TASK_INTERRUPTIBLE);
+-		ret = io_cqring_wait_schedule(ctx, &iowq, timeout);
+-		finish_wait(&ctx->cq_wait, &iowq.wq);
+-		cond_resched();
+-	} while (ret > 0);
+-
+-	restore_saved_sigmask_unless(ret == -EINTR);
+-
+-	return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
+-}
+-
+-static void io_free_page_table(void **table, size_t size)
+-{
+-	unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
+-
+-	for (i = 0; i < nr_tables; i++)
+-		kfree(table[i]);
+-	kfree(table);
+-}
+-
+-static void **io_alloc_page_table(size_t size)
+-{
+-	unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
+-	size_t init_size = size;
+-	void **table;
+-
+-	table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT);
+-	if (!table)
+-		return NULL;
+-
+-	for (i = 0; i < nr_tables; i++) {
+-		unsigned int this_size = min_t(size_t, size, PAGE_SIZE);
+-
+-		table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT);
+-		if (!table[i]) {
+-			io_free_page_table(table, init_size);
+-			return NULL;
+-		}
+-		size -= this_size;
+-	}
+-	return table;
+-}
+-
+-static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node)
+-{
+-	percpu_ref_exit(&ref_node->refs);
+-	kfree(ref_node);
+-}
+-
+-static void io_rsrc_node_ref_zero(struct percpu_ref *ref)
+-{
+-	struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs);
+-	struct io_ring_ctx *ctx = node->rsrc_data->ctx;
+-	unsigned long flags;
+-	bool first_add = false;
+-	unsigned long delay = HZ;
+-
+-	spin_lock_irqsave(&ctx->rsrc_ref_lock, flags);
+-	node->done = true;
+-
+-	/* if we are mid-quiesce then do not delay */
+-	if (node->rsrc_data->quiesce)
+-		delay = 0;
+-
+-	while (!list_empty(&ctx->rsrc_ref_list)) {
+-		node = list_first_entry(&ctx->rsrc_ref_list,
+-					    struct io_rsrc_node, node);
+-		/* recycle ref nodes in order */
+-		if (!node->done)
+-			break;
+-		list_del(&node->node);
+-		first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist);
+-	}
+-	spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags);
+-
+-	if (first_add)
+-		mod_delayed_work(system_wq, &ctx->rsrc_put_work, delay);
+-}
+-
+-static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx)
+-{
+-	struct io_rsrc_node *ref_node;
+-
+-	ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
+-	if (!ref_node)
+-		return NULL;
+-
+-	if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
+-			    0, GFP_KERNEL)) {
+-		kfree(ref_node);
+-		return NULL;
+-	}
+-	INIT_LIST_HEAD(&ref_node->node);
+-	INIT_LIST_HEAD(&ref_node->rsrc_list);
+-	ref_node->done = false;
+-	return ref_node;
+-}
+-
+-static void io_rsrc_node_switch(struct io_ring_ctx *ctx,
+-				struct io_rsrc_data *data_to_kill)
+-{
+-	WARN_ON_ONCE(!ctx->rsrc_backup_node);
+-	WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node);
+-
+-	if (data_to_kill) {
+-		struct io_rsrc_node *rsrc_node = ctx->rsrc_node;
+-
+-		rsrc_node->rsrc_data = data_to_kill;
+-		spin_lock_irq(&ctx->rsrc_ref_lock);
+-		list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list);
+-		spin_unlock_irq(&ctx->rsrc_ref_lock);
+-
+-		atomic_inc(&data_to_kill->refs);
+-		percpu_ref_kill(&rsrc_node->refs);
+-		ctx->rsrc_node = NULL;
+-	}
+-
+-	if (!ctx->rsrc_node) {
+-		ctx->rsrc_node = ctx->rsrc_backup_node;
+-		ctx->rsrc_backup_node = NULL;
+-	}
+-}
+-
+-static int io_rsrc_node_switch_start(struct io_ring_ctx *ctx)
+-{
+-	if (ctx->rsrc_backup_node)
+-		return 0;
+-	ctx->rsrc_backup_node = io_rsrc_node_alloc(ctx);
+-	return ctx->rsrc_backup_node ? 0 : -ENOMEM;
+-}
+-
+-static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, struct io_ring_ctx *ctx)
+-{
+-	int ret;
+-
+-	/* As we may drop ->uring_lock, other task may have started quiesce */
+-	if (data->quiesce)
+-		return -ENXIO;
+-
+-	data->quiesce = true;
+-	do {
+-		ret = io_rsrc_node_switch_start(ctx);
+-		if (ret)
+-			break;
+-		io_rsrc_node_switch(ctx, data);
+-
+-		/* kill initial ref, already quiesced if zero */
+-		if (atomic_dec_and_test(&data->refs))
+-			break;
+-		mutex_unlock(&ctx->uring_lock);
+-		flush_delayed_work(&ctx->rsrc_put_work);
+-		ret = wait_for_completion_interruptible(&data->done);
+-		if (!ret) {
+-			mutex_lock(&ctx->uring_lock);
+-			if (atomic_read(&data->refs) > 0) {
+-				/*
+-				 * it has been revived by another thread while
+-				 * we were unlocked
+-				 */
+-				mutex_unlock(&ctx->uring_lock);
+-			} else {
+-				break;
+-			}
+-		}
+-
+-		atomic_inc(&data->refs);
+-		/* wait for all works potentially completing data->done */
+-		flush_delayed_work(&ctx->rsrc_put_work);
+-		reinit_completion(&data->done);
+-
+-		ret = io_run_task_work_sig();
+-		mutex_lock(&ctx->uring_lock);
+-	} while (ret >= 0);
+-	data->quiesce = false;
+-
+-	return ret;
+-}
+-
+-static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
+-{
+-	unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
+-	unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
+-
+-	return &data->tags[table_idx][off];
+-}
+-
+-static void io_rsrc_data_free(struct io_rsrc_data *data)
+-{
+-	size_t size = data->nr * sizeof(data->tags[0][0]);
+-
+-	if (data->tags)
+-		io_free_page_table((void **)data->tags, size);
+-	kfree(data);
+-}
+-
+-static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put,
+-			      u64 __user *utags, unsigned nr,
+-			      struct io_rsrc_data **pdata)
+-{
+-	struct io_rsrc_data *data;
+-	int ret = -ENOMEM;
+-	unsigned i;
+-
+-	data = kzalloc(sizeof(*data), GFP_KERNEL);
+-	if (!data)
+-		return -ENOMEM;
+-	data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0]));
+-	if (!data->tags) {
+-		kfree(data);
+-		return -ENOMEM;
+-	}
+-
+-	data->nr = nr;
+-	data->ctx = ctx;
+-	data->do_put = do_put;
+-	if (utags) {
+-		ret = -EFAULT;
+-		for (i = 0; i < nr; i++) {
+-			u64 *tag_slot = io_get_tag_slot(data, i);
+-
+-			if (copy_from_user(tag_slot, &utags[i],
+-					   sizeof(*tag_slot)))
+-				goto fail;
+-		}
+-	}
+-
+-	atomic_set(&data->refs, 1);
+-	init_completion(&data->done);
+-	*pdata = data;
+-	return 0;
+-fail:
+-	io_rsrc_data_free(data);
+-	return ret;
+-}
+-
+-static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
+-{
+-	table->files = kvcalloc(nr_files, sizeof(table->files[0]),
+-				GFP_KERNEL_ACCOUNT);
+-	return !!table->files;
+-}
+-
+-static void io_free_file_tables(struct io_file_table *table)
+-{
+-	kvfree(table->files);
+-	table->files = NULL;
+-}
+-
+-static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
+-{
+-#if defined(CONFIG_UNIX)
+-	if (ctx->ring_sock) {
+-		struct sock *sock = ctx->ring_sock->sk;
+-		struct sk_buff *skb;
+-
+-		while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
+-			kfree_skb(skb);
+-	}
+-#else
+-	int i;
+-
+-	for (i = 0; i < ctx->nr_user_files; i++) {
+-		struct file *file;
+-
+-		file = io_file_from_index(ctx, i);
+-		if (file)
+-			fput(file);
+-	}
+-#endif
+-	io_free_file_tables(&ctx->file_table);
+-	io_rsrc_data_free(ctx->file_data);
+-	ctx->file_data = NULL;
+-	ctx->nr_user_files = 0;
+-}
+-
+-static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
+-{
+-	unsigned nr = ctx->nr_user_files;
+-	int ret;
+-
+-	if (!ctx->file_data)
+-		return -ENXIO;
+-
+-	/*
+-	 * Quiesce may unlock ->uring_lock, and while it's not held
+-	 * prevent new requests using the table.
+-	 */
+-	ctx->nr_user_files = 0;
+-	ret = io_rsrc_ref_quiesce(ctx->file_data, ctx);
+-	ctx->nr_user_files = nr;
+-	if (!ret)
+-		__io_sqe_files_unregister(ctx);
+-	return ret;
+-}
+-
+-static void io_sq_thread_unpark(struct io_sq_data *sqd)
+-	__releases(&sqd->lock)
+-{
+-	WARN_ON_ONCE(sqd->thread == current);
+-
+-	/*
+-	 * Do the dance but not conditional clear_bit() because it'd race with
+-	 * other threads incrementing park_pending and setting the bit.
+-	 */
+-	clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
+-	if (atomic_dec_return(&sqd->park_pending))
+-		set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
+-	mutex_unlock(&sqd->lock);
+-}
+-
+-static void io_sq_thread_park(struct io_sq_data *sqd)
+-	__acquires(&sqd->lock)
+-{
+-	WARN_ON_ONCE(sqd->thread == current);
+-
+-	atomic_inc(&sqd->park_pending);
+-	set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
+-	mutex_lock(&sqd->lock);
+-	if (sqd->thread)
+-		wake_up_process(sqd->thread);
+-}
+-
+-static void io_sq_thread_stop(struct io_sq_data *sqd)
+-{
+-	WARN_ON_ONCE(sqd->thread == current);
+-	WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state));
+-
+-	set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
+-	mutex_lock(&sqd->lock);
+-	if (sqd->thread)
+-		wake_up_process(sqd->thread);
+-	mutex_unlock(&sqd->lock);
+-	wait_for_completion(&sqd->exited);
+-}
+-
+-static void io_put_sq_data(struct io_sq_data *sqd)
+-{
+-	if (refcount_dec_and_test(&sqd->refs)) {
+-		WARN_ON_ONCE(atomic_read(&sqd->park_pending));
+-
+-		io_sq_thread_stop(sqd);
+-		kfree(sqd);
+-	}
+-}
+-
+-static void io_sq_thread_finish(struct io_ring_ctx *ctx)
+-{
+-	struct io_sq_data *sqd = ctx->sq_data;
+-
+-	if (sqd) {
+-		io_sq_thread_park(sqd);
+-		list_del_init(&ctx->sqd_list);
+-		io_sqd_update_thread_idle(sqd);
+-		io_sq_thread_unpark(sqd);
+-
+-		io_put_sq_data(sqd);
+-		ctx->sq_data = NULL;
+-	}
+-}
+-
+-static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
+-{
+-	struct io_ring_ctx *ctx_attach;
+-	struct io_sq_data *sqd;
+-	struct fd f;
+-
+-	f = fdget(p->wq_fd);
+-	if (!f.file)
+-		return ERR_PTR(-ENXIO);
+-	if (f.file->f_op != &io_uring_fops) {
+-		fdput(f);
+-		return ERR_PTR(-EINVAL);
+-	}
+-
+-	ctx_attach = f.file->private_data;
+-	sqd = ctx_attach->sq_data;
+-	if (!sqd) {
+-		fdput(f);
+-		return ERR_PTR(-EINVAL);
+-	}
+-	if (sqd->task_tgid != current->tgid) {
+-		fdput(f);
+-		return ERR_PTR(-EPERM);
+-	}
+-
+-	refcount_inc(&sqd->refs);
+-	fdput(f);
+-	return sqd;
+-}
+-
+-static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
+-					 bool *attached)
+-{
+-	struct io_sq_data *sqd;
+-
+-	*attached = false;
+-	if (p->flags & IORING_SETUP_ATTACH_WQ) {
+-		sqd = io_attach_sq_data(p);
+-		if (!IS_ERR(sqd)) {
+-			*attached = true;
+-			return sqd;
+-		}
+-		/* fall through for EPERM case, setup new sqd/task */
+-		if (PTR_ERR(sqd) != -EPERM)
+-			return sqd;
+-	}
+-
+-	sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
+-	if (!sqd)
+-		return ERR_PTR(-ENOMEM);
+-
+-	atomic_set(&sqd->park_pending, 0);
+-	refcount_set(&sqd->refs, 1);
+-	INIT_LIST_HEAD(&sqd->ctx_list);
+-	mutex_init(&sqd->lock);
+-	init_waitqueue_head(&sqd->wait);
+-	init_completion(&sqd->exited);
+-	return sqd;
+-}
+-
+-#if defined(CONFIG_UNIX)
+-/*
+- * Ensure the UNIX gc is aware of our file set, so we are certain that
+- * the io_uring can be safely unregistered on process exit, even if we have
+- * loops in the file referencing.
+- */
+-static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
+-{
+-	struct sock *sk = ctx->ring_sock->sk;
+-	struct scm_fp_list *fpl;
+-	struct sk_buff *skb;
+-	int i, nr_files;
+-
+-	fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
+-	if (!fpl)
+-		return -ENOMEM;
+-
+-	skb = alloc_skb(0, GFP_KERNEL);
+-	if (!skb) {
+-		kfree(fpl);
+-		return -ENOMEM;
+-	}
+-
+-	skb->sk = sk;
+-	skb->scm_io_uring = 1;
+-
+-	nr_files = 0;
+-	fpl->user = get_uid(current_user());
+-	for (i = 0; i < nr; i++) {
+-		struct file *file = io_file_from_index(ctx, i + offset);
+-
+-		if (!file)
+-			continue;
+-		fpl->fp[nr_files] = get_file(file);
+-		unix_inflight(fpl->user, fpl->fp[nr_files]);
+-		nr_files++;
+-	}
+-
+-	if (nr_files) {
+-		fpl->max = SCM_MAX_FD;
+-		fpl->count = nr_files;
+-		UNIXCB(skb).fp = fpl;
+-		skb->destructor = unix_destruct_scm;
+-		refcount_add(skb->truesize, &sk->sk_wmem_alloc);
+-		skb_queue_head(&sk->sk_receive_queue, skb);
+-
+-		for (i = 0; i < nr; i++) {
+-			struct file *file = io_file_from_index(ctx, i + offset);
+-
+-			if (file)
+-				fput(file);
+-		}
+-	} else {
+-		kfree_skb(skb);
+-		free_uid(fpl->user);
+-		kfree(fpl);
+-	}
+-
+-	return 0;
+-}
+-
+-/*
+- * If UNIX sockets are enabled, fd passing can cause a reference cycle which
+- * causes regular reference counting to break down. We rely on the UNIX
+- * garbage collection to take care of this problem for us.
+- */
+-static int io_sqe_files_scm(struct io_ring_ctx *ctx)
+-{
+-	unsigned left, total;
+-	int ret = 0;
+-
+-	total = 0;
+-	left = ctx->nr_user_files;
+-	while (left) {
+-		unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
+-
+-		ret = __io_sqe_files_scm(ctx, this_files, total);
+-		if (ret)
+-			break;
+-		left -= this_files;
+-		total += this_files;
+-	}
+-
+-	if (!ret)
+-		return 0;
+-
+-	while (total < ctx->nr_user_files) {
+-		struct file *file = io_file_from_index(ctx, total);
+-
+-		if (file)
+-			fput(file);
+-		total++;
+-	}
+-
+-	return ret;
+-}
+-#else
+-static int io_sqe_files_scm(struct io_ring_ctx *ctx)
+-{
+-	return 0;
+-}
+-#endif
+-
+-static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
+-{
+-	struct file *file = prsrc->file;
+-#if defined(CONFIG_UNIX)
+-	struct sock *sock = ctx->ring_sock->sk;
+-	struct sk_buff_head list, *head = &sock->sk_receive_queue;
+-	struct sk_buff *skb;
+-	int i;
+-
+-	__skb_queue_head_init(&list);
+-
+-	/*
+-	 * Find the skb that holds this file in its SCM_RIGHTS. When found,
+-	 * remove this entry and rearrange the file array.
+-	 */
+-	skb = skb_dequeue(head);
+-	while (skb) {
+-		struct scm_fp_list *fp;
+-
+-		fp = UNIXCB(skb).fp;
+-		for (i = 0; i < fp->count; i++) {
+-			int left;
+-
+-			if (fp->fp[i] != file)
+-				continue;
+-
+-			unix_notinflight(fp->user, fp->fp[i]);
+-			left = fp->count - 1 - i;
+-			if (left) {
+-				memmove(&fp->fp[i], &fp->fp[i + 1],
+-						left * sizeof(struct file *));
+-			}
+-			fp->count--;
+-			if (!fp->count) {
+-				kfree_skb(skb);
+-				skb = NULL;
+-			} else {
+-				__skb_queue_tail(&list, skb);
+-			}
+-			fput(file);
+-			file = NULL;
+-			break;
+-		}
+-
+-		if (!file)
+-			break;
+-
+-		__skb_queue_tail(&list, skb);
+-
+-		skb = skb_dequeue(head);
+-	}
+-
+-	if (skb_peek(&list)) {
+-		spin_lock_irq(&head->lock);
+-		while ((skb = __skb_dequeue(&list)) != NULL)
+-			__skb_queue_tail(head, skb);
+-		spin_unlock_irq(&head->lock);
+-	}
+-#else
+-	fput(file);
+-#endif
+-}
+-
+-static void __io_rsrc_put_work(struct io_rsrc_node *ref_node)
+-{
+-	struct io_rsrc_data *rsrc_data = ref_node->rsrc_data;
+-	struct io_ring_ctx *ctx = rsrc_data->ctx;
+-	struct io_rsrc_put *prsrc, *tmp;
+-
+-	list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
+-		list_del(&prsrc->list);
+-
+-		if (prsrc->tag) {
+-			bool lock_ring = ctx->flags & IORING_SETUP_IOPOLL;
+-
+-			io_ring_submit_lock(ctx, lock_ring);
+-			spin_lock(&ctx->completion_lock);
+-			io_fill_cqe_aux(ctx, prsrc->tag, 0, 0);
+-			io_commit_cqring(ctx);
+-			spin_unlock(&ctx->completion_lock);
+-			io_cqring_ev_posted(ctx);
+-			io_ring_submit_unlock(ctx, lock_ring);
+-		}
+-
+-		rsrc_data->do_put(ctx, prsrc);
+-		kfree(prsrc);
+-	}
+-
+-	io_rsrc_node_destroy(ref_node);
+-	if (atomic_dec_and_test(&rsrc_data->refs))
+-		complete(&rsrc_data->done);
+-}
+-
+-static void io_rsrc_put_work(struct work_struct *work)
+-{
+-	struct io_ring_ctx *ctx;
+-	struct llist_node *node;
+-
+-	ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
+-	node = llist_del_all(&ctx->rsrc_put_llist);
+-
+-	while (node) {
+-		struct io_rsrc_node *ref_node;
+-		struct llist_node *next = node->next;
+-
+-		ref_node = llist_entry(node, struct io_rsrc_node, llist);
+-		__io_rsrc_put_work(ref_node);
+-		node = next;
+-	}
+-}
+-
+-static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
+-				 unsigned nr_args, u64 __user *tags)
+-{
+-	__s32 __user *fds = (__s32 __user *) arg;
+-	struct file *file;
+-	int fd, ret;
+-	unsigned i;
+-
+-	if (ctx->file_data)
+-		return -EBUSY;
+-	if (!nr_args)
+-		return -EINVAL;
+-	if (nr_args > IORING_MAX_FIXED_FILES)
+-		return -EMFILE;
+-	if (nr_args > rlimit(RLIMIT_NOFILE))
+-		return -EMFILE;
+-	ret = io_rsrc_node_switch_start(ctx);
+-	if (ret)
+-		return ret;
+-	ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args,
+-				 &ctx->file_data);
+-	if (ret)
+-		return ret;
+-
+-	ret = -ENOMEM;
+-	if (!io_alloc_file_tables(&ctx->file_table, nr_args))
+-		goto out_free;
+-
+-	for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
+-		if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
+-			ret = -EFAULT;
+-			goto out_fput;
+-		}
+-		/* allow sparse sets */
+-		if (fd == -1) {
+-			ret = -EINVAL;
+-			if (unlikely(*io_get_tag_slot(ctx->file_data, i)))
+-				goto out_fput;
+-			continue;
+-		}
+-
+-		file = fget(fd);
+-		ret = -EBADF;
+-		if (unlikely(!file))
+-			goto out_fput;
+-
+-		/*
+-		 * Don't allow io_uring instances to be registered. If UNIX
+-		 * isn't enabled, then this causes a reference cycle and this
+-		 * instance can never get freed. If UNIX is enabled we'll
+-		 * handle it just fine, but there's still no point in allowing
+-		 * a ring fd as it doesn't support regular read/write anyway.
+-		 */
+-		if (file->f_op == &io_uring_fops) {
+-			fput(file);
+-			goto out_fput;
+-		}
+-		io_fixed_file_set(io_fixed_file_slot(&ctx->file_table, i), file);
+-	}
+-
+-	ret = io_sqe_files_scm(ctx);
+-	if (ret) {
+-		__io_sqe_files_unregister(ctx);
+-		return ret;
+-	}
+-
+-	io_rsrc_node_switch(ctx, NULL);
+-	return ret;
+-out_fput:
+-	for (i = 0; i < ctx->nr_user_files; i++) {
+-		file = io_file_from_index(ctx, i);
+-		if (file)
+-			fput(file);
+-	}
+-	io_free_file_tables(&ctx->file_table);
+-	ctx->nr_user_files = 0;
+-out_free:
+-	io_rsrc_data_free(ctx->file_data);
+-	ctx->file_data = NULL;
+-	return ret;
+-}
+-
+-static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
+-				int index)
+-{
+-#if defined(CONFIG_UNIX)
+-	struct sock *sock = ctx->ring_sock->sk;
+-	struct sk_buff_head *head = &sock->sk_receive_queue;
+-	struct sk_buff *skb;
+-
+-	/*
+-	 * See if we can merge this file into an existing skb SCM_RIGHTS
+-	 * file set. If there's no room, fall back to allocating a new skb
+-	 * and filling it in.
+-	 */
+-	spin_lock_irq(&head->lock);
+-	skb = skb_peek(head);
+-	if (skb) {
+-		struct scm_fp_list *fpl = UNIXCB(skb).fp;
+-
+-		if (fpl->count < SCM_MAX_FD) {
+-			__skb_unlink(skb, head);
+-			spin_unlock_irq(&head->lock);
+-			fpl->fp[fpl->count] = get_file(file);
+-			unix_inflight(fpl->user, fpl->fp[fpl->count]);
+-			fpl->count++;
+-			spin_lock_irq(&head->lock);
+-			__skb_queue_head(head, skb);
+-		} else {
+-			skb = NULL;
+-		}
+-	}
+-	spin_unlock_irq(&head->lock);
+-
+-	if (skb) {
+-		fput(file);
+-		return 0;
+-	}
+-
+-	return __io_sqe_files_scm(ctx, 1, index);
+-#else
+-	return 0;
+-#endif
+-}
+-
+-static int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
+-				 struct io_rsrc_node *node, void *rsrc)
+-{
+-	u64 *tag_slot = io_get_tag_slot(data, idx);
+-	struct io_rsrc_put *prsrc;
+-
+-	prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
+-	if (!prsrc)
+-		return -ENOMEM;
+-
+-	prsrc->tag = *tag_slot;
+-	*tag_slot = 0;
+-	prsrc->rsrc = rsrc;
+-	list_add(&prsrc->list, &node->rsrc_list);
+-	return 0;
+-}
+-
+-static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
+-				 unsigned int issue_flags, u32 slot_index)
+-{
+-	struct io_ring_ctx *ctx = req->ctx;
+-	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
+-	bool needs_switch = false;
+-	struct io_fixed_file *file_slot;
+-	int ret = -EBADF;
+-
+-	io_ring_submit_lock(ctx, !force_nonblock);
+-	if (file->f_op == &io_uring_fops)
+-		goto err;
+-	ret = -ENXIO;
+-	if (!ctx->file_data)
+-		goto err;
+-	ret = -EINVAL;
+-	if (slot_index >= ctx->nr_user_files)
+-		goto err;
+-
+-	slot_index = array_index_nospec(slot_index, ctx->nr_user_files);
+-	file_slot = io_fixed_file_slot(&ctx->file_table, slot_index);
+-
+-	if (file_slot->file_ptr) {
+-		struct file *old_file;
+-
+-		ret = io_rsrc_node_switch_start(ctx);
+-		if (ret)
+-			goto err;
+-
+-		old_file = (struct file *)(file_slot->file_ptr & FFS_MASK);
+-		ret = io_queue_rsrc_removal(ctx->file_data, slot_index,
+-					    ctx->rsrc_node, old_file);
+-		if (ret)
+-			goto err;
+-		file_slot->file_ptr = 0;
+-		needs_switch = true;
+-	}
+-
+-	*io_get_tag_slot(ctx->file_data, slot_index) = 0;
+-	io_fixed_file_set(file_slot, file);
+-	ret = io_sqe_file_register(ctx, file, slot_index);
+-	if (ret) {
+-		file_slot->file_ptr = 0;
+-		goto err;
+-	}
+-
+-	ret = 0;
+-err:
+-	if (needs_switch)
+-		io_rsrc_node_switch(ctx, ctx->file_data);
+-	io_ring_submit_unlock(ctx, !force_nonblock);
+-	if (ret)
+-		fput(file);
+-	return ret;
+-}
+-
+-static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags)
+-{
+-	unsigned int offset = req->close.file_slot - 1;
+-	struct io_ring_ctx *ctx = req->ctx;
+-	struct io_fixed_file *file_slot;
+-	struct file *file;
+-	int ret;
+-
+-	io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+-	ret = -ENXIO;
+-	if (unlikely(!ctx->file_data))
+-		goto out;
+-	ret = -EINVAL;
+-	if (offset >= ctx->nr_user_files)
+-		goto out;
+-	ret = io_rsrc_node_switch_start(ctx);
+-	if (ret)
+-		goto out;
+-
+-	offset = array_index_nospec(offset, ctx->nr_user_files);
+-	file_slot = io_fixed_file_slot(&ctx->file_table, offset);
+-	ret = -EBADF;
+-	if (!file_slot->file_ptr)
+-		goto out;
+-
+-	file = (struct file *)(file_slot->file_ptr & FFS_MASK);
+-	ret = io_queue_rsrc_removal(ctx->file_data, offset, ctx->rsrc_node, file);
+-	if (ret)
+-		goto out;
+-
+-	file_slot->file_ptr = 0;
+-	io_rsrc_node_switch(ctx, ctx->file_data);
+-	ret = 0;
+-out:
+-	io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
+-	return ret;
+-}
+-
+-static int __io_sqe_files_update(struct io_ring_ctx *ctx,
+-				 struct io_uring_rsrc_update2 *up,
+-				 unsigned nr_args)
+-{
+-	u64 __user *tags = u64_to_user_ptr(up->tags);
+-	__s32 __user *fds = u64_to_user_ptr(up->data);
+-	struct io_rsrc_data *data = ctx->file_data;
+-	struct io_fixed_file *file_slot;
+-	struct file *file;
+-	int fd, i, err = 0;
+-	unsigned int done;
+-	bool needs_switch = false;
+-
+-	if (!ctx->file_data)
+-		return -ENXIO;
+-	if (up->offset + nr_args > ctx->nr_user_files)
+-		return -EINVAL;
+-
+-	for (done = 0; done < nr_args; done++) {
+-		u64 tag = 0;
+-
+-		if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) ||
+-		    copy_from_user(&fd, &fds[done], sizeof(fd))) {
+-			err = -EFAULT;
+-			break;
+-		}
+-		if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) {
+-			err = -EINVAL;
+-			break;
+-		}
+-		if (fd == IORING_REGISTER_FILES_SKIP)
+-			continue;
+-
+-		i = array_index_nospec(up->offset + done, ctx->nr_user_files);
+-		file_slot = io_fixed_file_slot(&ctx->file_table, i);
+-
+-		if (file_slot->file_ptr) {
+-			file = (struct file *)(file_slot->file_ptr & FFS_MASK);
+-			err = io_queue_rsrc_removal(data, i, ctx->rsrc_node, file);
+-			if (err)
+-				break;
+-			file_slot->file_ptr = 0;
+-			needs_switch = true;
+-		}
+-		if (fd != -1) {
+-			file = fget(fd);
+-			if (!file) {
+-				err = -EBADF;
+-				break;
+-			}
+-			/*
+-			 * Don't allow io_uring instances to be registered. If
+-			 * UNIX isn't enabled, then this causes a reference
+-			 * cycle and this instance can never get freed. If UNIX
+-			 * is enabled we'll handle it just fine, but there's
+-			 * still no point in allowing a ring fd as it doesn't
+-			 * support regular read/write anyway.
+-			 */
+-			if (file->f_op == &io_uring_fops) {
+-				fput(file);
+-				err = -EBADF;
+-				break;
+-			}
+-			*io_get_tag_slot(data, i) = tag;
+-			io_fixed_file_set(file_slot, file);
+-			err = io_sqe_file_register(ctx, file, i);
+-			if (err) {
+-				file_slot->file_ptr = 0;
+-				fput(file);
+-				break;
+-			}
+-		}
+-	}
+-
+-	if (needs_switch)
+-		io_rsrc_node_switch(ctx, data);
+-	return done ? done : err;
+-}
+-
+-static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
+-					struct task_struct *task)
+-{
+-	struct io_wq_hash *hash;
+-	struct io_wq_data data;
+-	unsigned int concurrency;
+-
+-	mutex_lock(&ctx->uring_lock);
+-	hash = ctx->hash_map;
+-	if (!hash) {
+-		hash = kzalloc(sizeof(*hash), GFP_KERNEL);
+-		if (!hash) {
+-			mutex_unlock(&ctx->uring_lock);
+-			return ERR_PTR(-ENOMEM);
+-		}
+-		refcount_set(&hash->refs, 1);
+-		init_waitqueue_head(&hash->wait);
+-		ctx->hash_map = hash;
+-	}
+-	mutex_unlock(&ctx->uring_lock);
+-
+-	data.hash = hash;
+-	data.task = task;
+-	data.free_work = io_wq_free_work;
+-	data.do_work = io_wq_submit_work;
+-
+-	/* Do QD, or 4 * CPUS, whatever is smallest */
+-	concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
+-
+-	return io_wq_create(concurrency, &data);
+-}
+-
+-static int io_uring_alloc_task_context(struct task_struct *task,
+-				       struct io_ring_ctx *ctx)
+-{
+-	struct io_uring_task *tctx;
+-	int ret;
+-
+-	tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
+-	if (unlikely(!tctx))
+-		return -ENOMEM;
+-
+-	ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
+-	if (unlikely(ret)) {
+-		kfree(tctx);
+-		return ret;
+-	}
+-
+-	tctx->io_wq = io_init_wq_offload(ctx, task);
+-	if (IS_ERR(tctx->io_wq)) {
+-		ret = PTR_ERR(tctx->io_wq);
+-		percpu_counter_destroy(&tctx->inflight);
+-		kfree(tctx);
+-		return ret;
+-	}
+-
+-	xa_init(&tctx->xa);
+-	init_waitqueue_head(&tctx->wait);
+-	atomic_set(&tctx->in_idle, 0);
+-	atomic_set(&tctx->inflight_tracked, 0);
+-	task->io_uring = tctx;
+-	spin_lock_init(&tctx->task_lock);
+-	INIT_WQ_LIST(&tctx->task_list);
+-	init_task_work(&tctx->task_work, tctx_task_work);
+-	return 0;
+-}
+-
+-void __io_uring_free(struct task_struct *tsk)
+-{
+-	struct io_uring_task *tctx = tsk->io_uring;
+-
+-	WARN_ON_ONCE(!xa_empty(&tctx->xa));
+-	WARN_ON_ONCE(tctx->io_wq);
+-	WARN_ON_ONCE(tctx->cached_refs);
+-
+-	percpu_counter_destroy(&tctx->inflight);
+-	kfree(tctx);
+-	tsk->io_uring = NULL;
+-}
+-
+-static int io_sq_offload_create(struct io_ring_ctx *ctx,
+-				struct io_uring_params *p)
+-{
+-	int ret;
+-
+-	/* Retain compatibility with failing for an invalid attach attempt */
+-	if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
+-				IORING_SETUP_ATTACH_WQ) {
+-		struct fd f;
+-
+-		f = fdget(p->wq_fd);
+-		if (!f.file)
+-			return -ENXIO;
+-		if (f.file->f_op != &io_uring_fops) {
+-			fdput(f);
+-			return -EINVAL;
+-		}
+-		fdput(f);
+-	}
+-	if (ctx->flags & IORING_SETUP_SQPOLL) {
+-		struct task_struct *tsk;
+-		struct io_sq_data *sqd;
+-		bool attached;
+-
+-		sqd = io_get_sq_data(p, &attached);
+-		if (IS_ERR(sqd)) {
+-			ret = PTR_ERR(sqd);
+-			goto err;
+-		}
+-
+-		ctx->sq_creds = get_current_cred();
+-		ctx->sq_data = sqd;
+-		ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
+-		if (!ctx->sq_thread_idle)
+-			ctx->sq_thread_idle = HZ;
+-
+-		io_sq_thread_park(sqd);
+-		list_add(&ctx->sqd_list, &sqd->ctx_list);
+-		io_sqd_update_thread_idle(sqd);
+-		/* don't attach to a dying SQPOLL thread, would be racy */
+-		ret = (attached && !sqd->thread) ? -ENXIO : 0;
+-		io_sq_thread_unpark(sqd);
+-
+-		if (ret < 0)
+-			goto err;
+-		if (attached)
+-			return 0;
+-
+-		if (p->flags & IORING_SETUP_SQ_AFF) {
+-			int cpu = p->sq_thread_cpu;
+-
+-			ret = -EINVAL;
+-			if (cpu >= nr_cpu_ids || !cpu_online(cpu))
+-				goto err_sqpoll;
+-			sqd->sq_cpu = cpu;
+-		} else {
+-			sqd->sq_cpu = -1;
+-		}
+-
+-		sqd->task_pid = current->pid;
+-		sqd->task_tgid = current->tgid;
+-		tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
+-		if (IS_ERR(tsk)) {
+-			ret = PTR_ERR(tsk);
+-			goto err_sqpoll;
+-		}
+-
+-		sqd->thread = tsk;
+-		ret = io_uring_alloc_task_context(tsk, ctx);
+-		wake_up_new_task(tsk);
+-		if (ret)
+-			goto err;
+-	} else if (p->flags & IORING_SETUP_SQ_AFF) {
+-		/* Can't have SQ_AFF without SQPOLL */
+-		ret = -EINVAL;
+-		goto err;
+-	}
+-
+-	return 0;
+-err_sqpoll:
+-	complete(&ctx->sq_data->exited);
+-err:
+-	io_sq_thread_finish(ctx);
+-	return ret;
+-}
+-
+-static inline void __io_unaccount_mem(struct user_struct *user,
+-				      unsigned long nr_pages)
+-{
+-	atomic_long_sub(nr_pages, &user->locked_vm);
+-}
+-
+-static inline int __io_account_mem(struct user_struct *user,
+-				   unsigned long nr_pages)
+-{
+-	unsigned long page_limit, cur_pages, new_pages;
+-
+-	/* Don't allow more pages than we can safely lock */
+-	page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
+-
+-	do {
+-		cur_pages = atomic_long_read(&user->locked_vm);
+-		new_pages = cur_pages + nr_pages;
+-		if (new_pages > page_limit)
+-			return -ENOMEM;
+-	} while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
+-					new_pages) != cur_pages);
+-
+-	return 0;
+-}
+-
+-static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
+-{
+-	if (ctx->user)
+-		__io_unaccount_mem(ctx->user, nr_pages);
+-
+-	if (ctx->mm_account)
+-		atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
+-}
+-
+-static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
+-{
+-	int ret;
+-
+-	if (ctx->user) {
+-		ret = __io_account_mem(ctx->user, nr_pages);
+-		if (ret)
+-			return ret;
+-	}
+-
+-	if (ctx->mm_account)
+-		atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
+-
+-	return 0;
+-}
+-
+-static void io_mem_free(void *ptr)
+-{
+-	struct page *page;
+-
+-	if (!ptr)
+-		return;
+-
+-	page = virt_to_head_page(ptr);
+-	if (put_page_testzero(page))
+-		free_compound_page(page);
+-}
+-
+-static void *io_mem_alloc(size_t size)
+-{
+-	gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP;
+-
+-	return (void *) __get_free_pages(gfp, get_order(size));
+-}
+-
+-static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
+-				size_t *sq_offset)
+-{
+-	struct io_rings *rings;
+-	size_t off, sq_array_size;
+-
+-	off = struct_size(rings, cqes, cq_entries);
+-	if (off == SIZE_MAX)
+-		return SIZE_MAX;
+-
+-#ifdef CONFIG_SMP
+-	off = ALIGN(off, SMP_CACHE_BYTES);
+-	if (off == 0)
+-		return SIZE_MAX;
+-#endif
+-
+-	if (sq_offset)
+-		*sq_offset = off;
+-
+-	sq_array_size = array_size(sizeof(u32), sq_entries);
+-	if (sq_array_size == SIZE_MAX)
+-		return SIZE_MAX;
+-
+-	if (check_add_overflow(off, sq_array_size, &off))
+-		return SIZE_MAX;
+-
+-	return off;
+-}
+-
+-static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot)
+-{
+-	struct io_mapped_ubuf *imu = *slot;
+-	unsigned int i;
+-
+-	if (imu != ctx->dummy_ubuf) {
+-		for (i = 0; i < imu->nr_bvecs; i++)
+-			unpin_user_page(imu->bvec[i].bv_page);
+-		if (imu->acct_pages)
+-			io_unaccount_mem(ctx, imu->acct_pages);
+-		kvfree(imu);
+-	}
+-	*slot = NULL;
+-}
+-
+-static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
+-{
+-	io_buffer_unmap(ctx, &prsrc->buf);
+-	prsrc->buf = NULL;
+-}
+-
+-static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
+-{
+-	unsigned int i;
+-
+-	for (i = 0; i < ctx->nr_user_bufs; i++)
+-		io_buffer_unmap(ctx, &ctx->user_bufs[i]);
+-	kfree(ctx->user_bufs);
+-	io_rsrc_data_free(ctx->buf_data);
+-	ctx->user_bufs = NULL;
+-	ctx->buf_data = NULL;
+-	ctx->nr_user_bufs = 0;
+-}
+-
+-static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
+-{
+-	unsigned nr = ctx->nr_user_bufs;
+-	int ret;
+-
+-	if (!ctx->buf_data)
+-		return -ENXIO;
+-
+-	/*
+-	 * Quiesce may unlock ->uring_lock, and while it's not held
+-	 * prevent new requests using the table.
+-	 */
+-	ctx->nr_user_bufs = 0;
+-	ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx);
+-	ctx->nr_user_bufs = nr;
+-	if (!ret)
+-		__io_sqe_buffers_unregister(ctx);
+-	return ret;
+-}
+-
+-static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
+-		       void __user *arg, unsigned index)
+-{
+-	struct iovec __user *src;
+-
+-#ifdef CONFIG_COMPAT
+-	if (ctx->compat) {
+-		struct compat_iovec __user *ciovs;
+-		struct compat_iovec ciov;
+-
+-		ciovs = (struct compat_iovec __user *) arg;
+-		if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
+-			return -EFAULT;
+-
+-		dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
+-		dst->iov_len = ciov.iov_len;
+-		return 0;
+-	}
+-#endif
+-	src = (struct iovec __user *) arg;
+-	if (copy_from_user(dst, &src[index], sizeof(*dst)))
+-		return -EFAULT;
+-	return 0;
+-}
+-
+-/*
+- * Not super efficient, but this is just a registration time. And we do cache
+- * the last compound head, so generally we'll only do a full search if we don't
+- * match that one.
+- *
+- * We check if the given compound head page has already been accounted, to
+- * avoid double accounting it. This allows us to account the full size of the
+- * page, not just the constituent pages of a huge page.
+- */
+-static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
+-				  int nr_pages, struct page *hpage)
+-{
+-	int i, j;
+-
+-	/* check current page array */
+-	for (i = 0; i < nr_pages; i++) {
+-		if (!PageCompound(pages[i]))
+-			continue;
+-		if (compound_head(pages[i]) == hpage)
+-			return true;
+-	}
+-
+-	/* check previously registered pages */
+-	for (i = 0; i < ctx->nr_user_bufs; i++) {
+-		struct io_mapped_ubuf *imu = ctx->user_bufs[i];
+-
+-		for (j = 0; j < imu->nr_bvecs; j++) {
+-			if (!PageCompound(imu->bvec[j].bv_page))
+-				continue;
+-			if (compound_head(imu->bvec[j].bv_page) == hpage)
+-				return true;
+-		}
+-	}
+-
+-	return false;
+-}
+-
+-static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
+-				 int nr_pages, struct io_mapped_ubuf *imu,
+-				 struct page **last_hpage)
+-{
+-	int i, ret;
+-
+-	imu->acct_pages = 0;
+-	for (i = 0; i < nr_pages; i++) {
+-		if (!PageCompound(pages[i])) {
+-			imu->acct_pages++;
+-		} else {
+-			struct page *hpage;
+-
+-			hpage = compound_head(pages[i]);
+-			if (hpage == *last_hpage)
+-				continue;
+-			*last_hpage = hpage;
+-			if (headpage_already_acct(ctx, pages, i, hpage))
+-				continue;
+-			imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
+-		}
+-	}
+-
+-	if (!imu->acct_pages)
+-		return 0;
+-
+-	ret = io_account_mem(ctx, imu->acct_pages);
+-	if (ret)
+-		imu->acct_pages = 0;
+-	return ret;
+-}
+-
+-static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
+-				  struct io_mapped_ubuf **pimu,
+-				  struct page **last_hpage)
+-{
+-	struct io_mapped_ubuf *imu = NULL;
+-	struct vm_area_struct **vmas = NULL;
+-	struct page **pages = NULL;
+-	unsigned long off, start, end, ubuf;
+-	size_t size;
+-	int ret, pret, nr_pages, i;
+-
+-	if (!iov->iov_base) {
+-		*pimu = ctx->dummy_ubuf;
+-		return 0;
+-	}
+-
+-	ubuf = (unsigned long) iov->iov_base;
+-	end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+-	start = ubuf >> PAGE_SHIFT;
+-	nr_pages = end - start;
+-
+-	*pimu = NULL;
+-	ret = -ENOMEM;
+-
+-	pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
+-	if (!pages)
+-		goto done;
+-
+-	vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
+-			      GFP_KERNEL);
+-	if (!vmas)
+-		goto done;
+-
+-	imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL);
+-	if (!imu)
+-		goto done;
+-
+-	ret = 0;
+-	mmap_read_lock(current->mm);
+-	pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
+-			      pages, vmas);
+-	if (pret == nr_pages) {
+-		/* don't support file backed memory */
+-		for (i = 0; i < nr_pages; i++) {
+-			struct vm_area_struct *vma = vmas[i];
+-
+-			if (vma_is_shmem(vma))
+-				continue;
+-			if (vma->vm_file &&
+-			    !is_file_hugepages(vma->vm_file)) {
+-				ret = -EOPNOTSUPP;
+-				break;
+-			}
+-		}
+-	} else {
+-		ret = pret < 0 ? pret : -EFAULT;
+-	}
+-	mmap_read_unlock(current->mm);
+-	if (ret) {
+-		/*
+-		 * if we did partial map, or found file backed vmas,
+-		 * release any pages we did get
+-		 */
+-		if (pret > 0)
+-			unpin_user_pages(pages, pret);
+-		goto done;
+-	}
+-
+-	ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage);
+-	if (ret) {
+-		unpin_user_pages(pages, pret);
+-		goto done;
+-	}
+-
+-	off = ubuf & ~PAGE_MASK;
+-	size = iov->iov_len;
+-	for (i = 0; i < nr_pages; i++) {
+-		size_t vec_len;
+-
+-		vec_len = min_t(size_t, size, PAGE_SIZE - off);
+-		imu->bvec[i].bv_page = pages[i];
+-		imu->bvec[i].bv_len = vec_len;
+-		imu->bvec[i].bv_offset = off;
+-		off = 0;
+-		size -= vec_len;
+-	}
+-	/* store original address for later verification */
+-	imu->ubuf = ubuf;
+-	imu->ubuf_end = ubuf + iov->iov_len;
+-	imu->nr_bvecs = nr_pages;
+-	*pimu = imu;
+-	ret = 0;
+-done:
+-	if (ret)
+-		kvfree(imu);
+-	kvfree(pages);
+-	kvfree(vmas);
+-	return ret;
+-}
+-
+-static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
+-{
+-	ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL);
+-	return ctx->user_bufs ? 0 : -ENOMEM;
+-}
+-
+-static int io_buffer_validate(struct iovec *iov)
+-{
+-	unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1);
+-
+-	/*
+-	 * Don't impose further limits on the size and buffer
+-	 * constraints here, we'll -EINVAL later when IO is
+-	 * submitted if they are wrong.
+-	 */
+-	if (!iov->iov_base)
+-		return iov->iov_len ? -EFAULT : 0;
+-	if (!iov->iov_len)
+-		return -EFAULT;
+-
+-	/* arbitrary limit, but we need something */
+-	if (iov->iov_len > SZ_1G)
+-		return -EFAULT;
+-
+-	if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp))
+-		return -EOVERFLOW;
+-
+-	return 0;
+-}
+-
+-static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
+-				   unsigned int nr_args, u64 __user *tags)
+-{
+-	struct page *last_hpage = NULL;
+-	struct io_rsrc_data *data;
+-	int i, ret;
+-	struct iovec iov;
+-
+-	if (ctx->user_bufs)
+-		return -EBUSY;
+-	if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS)
+-		return -EINVAL;
+-	ret = io_rsrc_node_switch_start(ctx);
+-	if (ret)
+-		return ret;
+-	ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data);
+-	if (ret)
+-		return ret;
+-	ret = io_buffers_map_alloc(ctx, nr_args);
+-	if (ret) {
+-		io_rsrc_data_free(data);
+-		return ret;
+-	}
+-
+-	for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) {
+-		ret = io_copy_iov(ctx, &iov, arg, i);
+-		if (ret)
+-			break;
+-		ret = io_buffer_validate(&iov);
+-		if (ret)
+-			break;
+-		if (!iov.iov_base && *io_get_tag_slot(data, i)) {
+-			ret = -EINVAL;
+-			break;
+-		}
+-
+-		ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i],
+-					     &last_hpage);
+-		if (ret)
+-			break;
+-	}
+-
+-	WARN_ON_ONCE(ctx->buf_data);
+-
+-	ctx->buf_data = data;
+-	if (ret)
+-		__io_sqe_buffers_unregister(ctx);
+-	else
+-		io_rsrc_node_switch(ctx, NULL);
+-	return ret;
+-}
+-
+-static int __io_sqe_buffers_update(struct io_ring_ctx *ctx,
+-				   struct io_uring_rsrc_update2 *up,
+-				   unsigned int nr_args)
+-{
+-	u64 __user *tags = u64_to_user_ptr(up->tags);
+-	struct iovec iov, __user *iovs = u64_to_user_ptr(up->data);
+-	struct page *last_hpage = NULL;
+-	bool needs_switch = false;
+-	__u32 done;
+-	int i, err;
+-
+-	if (!ctx->buf_data)
+-		return -ENXIO;
+-	if (up->offset + nr_args > ctx->nr_user_bufs)
+-		return -EINVAL;
+-
+-	for (done = 0; done < nr_args; done++) {
+-		struct io_mapped_ubuf *imu;
+-		int offset = up->offset + done;
+-		u64 tag = 0;
+-
+-		err = io_copy_iov(ctx, &iov, iovs, done);
+-		if (err)
+-			break;
+-		if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) {
+-			err = -EFAULT;
+-			break;
+-		}
+-		err = io_buffer_validate(&iov);
+-		if (err)
+-			break;
+-		if (!iov.iov_base && tag) {
+-			err = -EINVAL;
+-			break;
+-		}
+-		err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage);
+-		if (err)
+-			break;
+-
+-		i = array_index_nospec(offset, ctx->nr_user_bufs);
+-		if (ctx->user_bufs[i] != ctx->dummy_ubuf) {
+-			err = io_queue_rsrc_removal(ctx->buf_data, i,
+-						    ctx->rsrc_node, ctx->user_bufs[i]);
+-			if (unlikely(err)) {
+-				io_buffer_unmap(ctx, &imu);
+-				break;
+-			}
+-			ctx->user_bufs[i] = NULL;
+-			needs_switch = true;
+-		}
+-
+-		ctx->user_bufs[i] = imu;
+-		*io_get_tag_slot(ctx->buf_data, offset) = tag;
+-	}
+-
+-	if (needs_switch)
+-		io_rsrc_node_switch(ctx, ctx->buf_data);
+-	return done ? done : err;
+-}
+-
+-static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
+-{
+-	__s32 __user *fds = arg;
+-	int fd;
+-
+-	if (ctx->cq_ev_fd)
+-		return -EBUSY;
+-
+-	if (copy_from_user(&fd, fds, sizeof(*fds)))
+-		return -EFAULT;
+-
+-	ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
+-	if (IS_ERR(ctx->cq_ev_fd)) {
+-		int ret = PTR_ERR(ctx->cq_ev_fd);
+-
+-		ctx->cq_ev_fd = NULL;
+-		return ret;
+-	}
+-
+-	return 0;
+-}
+-
+-static int io_eventfd_unregister(struct io_ring_ctx *ctx)
+-{
+-	if (ctx->cq_ev_fd) {
+-		eventfd_ctx_put(ctx->cq_ev_fd);
+-		ctx->cq_ev_fd = NULL;
+-		return 0;
+-	}
+-
+-	return -ENXIO;
+-}
+-
+-static void io_destroy_buffers(struct io_ring_ctx *ctx)
+-{
+-	struct io_buffer *buf;
+-	unsigned long index;
+-
+-	xa_for_each(&ctx->io_buffers, index, buf)
+-		__io_remove_buffers(ctx, buf, index, -1U);
+-}
+-
+-static void io_req_cache_free(struct list_head *list)
+-{
+-	struct io_kiocb *req, *nxt;
+-
+-	list_for_each_entry_safe(req, nxt, list, inflight_entry) {
+-		list_del(&req->inflight_entry);
+-		kmem_cache_free(req_cachep, req);
+-	}
+-}
+-
+-static void io_req_caches_free(struct io_ring_ctx *ctx)
+-{
+-	struct io_submit_state *state = &ctx->submit_state;
+-
+-	mutex_lock(&ctx->uring_lock);
+-
+-	if (state->free_reqs) {
+-		kmem_cache_free_bulk(req_cachep, state->free_reqs, state->reqs);
+-		state->free_reqs = 0;
+-	}
+-
+-	io_flush_cached_locked_reqs(ctx, state);
+-	io_req_cache_free(&state->free_list);
+-	mutex_unlock(&ctx->uring_lock);
+-}
+-
+-static void io_wait_rsrc_data(struct io_rsrc_data *data)
+-{
+-	if (data && !atomic_dec_and_test(&data->refs))
+-		wait_for_completion(&data->done);
+-}
+-
+-static void io_ring_ctx_free(struct io_ring_ctx *ctx)
+-{
+-	io_sq_thread_finish(ctx);
+-
+-	/* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */
+-	io_wait_rsrc_data(ctx->buf_data);
+-	io_wait_rsrc_data(ctx->file_data);
+-
+-	mutex_lock(&ctx->uring_lock);
+-	if (ctx->buf_data)
+-		__io_sqe_buffers_unregister(ctx);
+-	if (ctx->file_data)
+-		__io_sqe_files_unregister(ctx);
+-	if (ctx->rings)
+-		__io_cqring_overflow_flush(ctx, true);
+-	mutex_unlock(&ctx->uring_lock);
+-	io_eventfd_unregister(ctx);
+-	io_destroy_buffers(ctx);
+-	if (ctx->sq_creds)
+-		put_cred(ctx->sq_creds);
+-
+-	/* there are no registered resources left, nobody uses it */
+-	if (ctx->rsrc_node)
+-		io_rsrc_node_destroy(ctx->rsrc_node);
+-	if (ctx->rsrc_backup_node)
+-		io_rsrc_node_destroy(ctx->rsrc_backup_node);
+-	flush_delayed_work(&ctx->rsrc_put_work);
+-
+-	WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list));
+-	WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist));
+-
+-#if defined(CONFIG_UNIX)
+-	if (ctx->ring_sock) {
+-		ctx->ring_sock->file = NULL; /* so that iput() is called */
+-		sock_release(ctx->ring_sock);
+-	}
+-#endif
+-	WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list));
+-
+-	if (ctx->mm_account) {
+-		mmdrop(ctx->mm_account);
+-		ctx->mm_account = NULL;
+-	}
+-
+-	io_mem_free(ctx->rings);
+-	io_mem_free(ctx->sq_sqes);
+-
+-	percpu_ref_exit(&ctx->refs);
+-	free_uid(ctx->user);
+-	io_req_caches_free(ctx);
+-	if (ctx->hash_map)
+-		io_wq_put_hash(ctx->hash_map);
+-	kfree(ctx->cancel_hash);
+-	kfree(ctx->dummy_ubuf);
+-	kfree(ctx);
+-}
+-
+-static __poll_t io_uring_poll(struct file *file, poll_table *wait)
+-{
+-	struct io_ring_ctx *ctx = file->private_data;
+-	__poll_t mask = 0;
+-
+-	poll_wait(file, &ctx->poll_wait, wait);
+-	/*
+-	 * synchronizes with barrier from wq_has_sleeper call in
+-	 * io_commit_cqring
+-	 */
+-	smp_rmb();
+-	if (!io_sqring_full(ctx))
+-		mask |= EPOLLOUT | EPOLLWRNORM;
+-
+-	/*
+-	 * Don't flush cqring overflow list here, just do a simple check.
+-	 * Otherwise there could possible be ABBA deadlock:
+-	 *      CPU0                    CPU1
+-	 *      ----                    ----
+-	 * lock(&ctx->uring_lock);
+-	 *                              lock(&ep->mtx);
+-	 *                              lock(&ctx->uring_lock);
+-	 * lock(&ep->mtx);
+-	 *
+-	 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
+-	 * pushs them to do the flush.
+-	 */
+-	if (io_cqring_events(ctx) || test_bit(0, &ctx->check_cq_overflow))
+-		mask |= EPOLLIN | EPOLLRDNORM;
+-
+-	return mask;
+-}
+-
+-static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
+-{
+-	const struct cred *creds;
+-
+-	creds = xa_erase(&ctx->personalities, id);
+-	if (creds) {
+-		put_cred(creds);
+-		return 0;
+-	}
+-
+-	return -EINVAL;
+-}
+-
+-struct io_tctx_exit {
+-	struct callback_head		task_work;
+-	struct completion		completion;
+-	struct io_ring_ctx		*ctx;
+-};
+-
+-static void io_tctx_exit_cb(struct callback_head *cb)
+-{
+-	struct io_uring_task *tctx = current->io_uring;
+-	struct io_tctx_exit *work;
+-
+-	work = container_of(cb, struct io_tctx_exit, task_work);
+-	/*
+-	 * When @in_idle, we're in cancellation and it's racy to remove the
+-	 * node. It'll be removed by the end of cancellation, just ignore it.
+-	 */
+-	if (!atomic_read(&tctx->in_idle))
+-		io_uring_del_tctx_node((unsigned long)work->ctx);
+-	complete(&work->completion);
+-}
+-
+-static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
+-{
+-	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
+-
+-	return req->ctx == data;
+-}
+-
+-static void io_ring_exit_work(struct work_struct *work)
+-{
+-	struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
+-	unsigned long timeout = jiffies + HZ * 60 * 5;
+-	unsigned long interval = HZ / 20;
+-	struct io_tctx_exit exit;
+-	struct io_tctx_node *node;
+-	int ret;
+-
+-	/*
+-	 * If we're doing polled IO and end up having requests being
+-	 * submitted async (out-of-line), then completions can come in while
+-	 * we're waiting for refs to drop. We need to reap these manually,
+-	 * as nobody else will be looking for them.
+-	 */
+-	do {
+-		io_uring_try_cancel_requests(ctx, NULL, true);
+-		if (ctx->sq_data) {
+-			struct io_sq_data *sqd = ctx->sq_data;
+-			struct task_struct *tsk;
+-
+-			io_sq_thread_park(sqd);
+-			tsk = sqd->thread;
+-			if (tsk && tsk->io_uring && tsk->io_uring->io_wq)
+-				io_wq_cancel_cb(tsk->io_uring->io_wq,
+-						io_cancel_ctx_cb, ctx, true);
+-			io_sq_thread_unpark(sqd);
+-		}
+-
+-		if (WARN_ON_ONCE(time_after(jiffies, timeout))) {
+-			/* there is little hope left, don't run it too often */
+-			interval = HZ * 60;
+-		}
+-	} while (!wait_for_completion_timeout(&ctx->ref_comp, interval));
+-
+-	init_completion(&exit.completion);
+-	init_task_work(&exit.task_work, io_tctx_exit_cb);
+-	exit.ctx = ctx;
+-	/*
+-	 * Some may use context even when all refs and requests have been put,
+-	 * and they are free to do so while still holding uring_lock or
+-	 * completion_lock, see io_req_task_submit(). Apart from other work,
+-	 * this lock/unlock section also waits them to finish.
+-	 */
+-	mutex_lock(&ctx->uring_lock);
+-	while (!list_empty(&ctx->tctx_list)) {
+-		WARN_ON_ONCE(time_after(jiffies, timeout));
+-
+-		node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
+-					ctx_node);
+-		/* don't spin on a single task if cancellation failed */
+-		list_rotate_left(&ctx->tctx_list);
+-		ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
+-		if (WARN_ON_ONCE(ret))
+-			continue;
+-		wake_up_process(node->task);
+-
+-		mutex_unlock(&ctx->uring_lock);
+-		wait_for_completion(&exit.completion);
+-		mutex_lock(&ctx->uring_lock);
+-	}
+-	mutex_unlock(&ctx->uring_lock);
+-	spin_lock(&ctx->completion_lock);
+-	spin_unlock(&ctx->completion_lock);
+-
+-	io_ring_ctx_free(ctx);
+-}
+-
+-/* Returns true if we found and killed one or more timeouts */
+-static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
+-			     bool cancel_all)
+-{
+-	struct io_kiocb *req, *tmp;
+-	int canceled = 0;
+-
+-	spin_lock(&ctx->completion_lock);
+-	spin_lock_irq(&ctx->timeout_lock);
+-	list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
+-		if (io_match_task(req, tsk, cancel_all)) {
+-			io_kill_timeout(req, -ECANCELED);
+-			canceled++;
+-		}
+-	}
+-	spin_unlock_irq(&ctx->timeout_lock);
+-	if (canceled != 0)
+-		io_commit_cqring(ctx);
+-	spin_unlock(&ctx->completion_lock);
+-	if (canceled != 0)
+-		io_cqring_ev_posted(ctx);
+-	return canceled != 0;
+-}
+-
+-static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
+-{
+-	unsigned long index;
+-	struct creds *creds;
+-
+-	mutex_lock(&ctx->uring_lock);
+-	percpu_ref_kill(&ctx->refs);
+-	if (ctx->rings)
+-		__io_cqring_overflow_flush(ctx, true);
+-	xa_for_each(&ctx->personalities, index, creds)
+-		io_unregister_personality(ctx, index);
+-	mutex_unlock(&ctx->uring_lock);
+-
+-	io_kill_timeouts(ctx, NULL, true);
+-	io_poll_remove_all(ctx, NULL, true);
+-
+-	/* if we failed setting up the ctx, we might not have any rings */
+-	io_iopoll_try_reap_events(ctx);
+-
+-	INIT_WORK(&ctx->exit_work, io_ring_exit_work);
+-	/*
+-	 * Use system_unbound_wq to avoid spawning tons of event kworkers
+-	 * if we're exiting a ton of rings at the same time. It just adds
+-	 * noise and overhead, there's no discernable change in runtime
+-	 * over using system_wq.
+-	 */
+-	queue_work(system_unbound_wq, &ctx->exit_work);
+-}
+-
+-static int io_uring_release(struct inode *inode, struct file *file)
+-{
+-	struct io_ring_ctx *ctx = file->private_data;
+-
+-	file->private_data = NULL;
+-	io_ring_ctx_wait_and_kill(ctx);
+-	return 0;
+-}
+-
+-struct io_task_cancel {
+-	struct task_struct *task;
+-	bool all;
+-};
+-
+-static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
+-{
+-	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
+-	struct io_task_cancel *cancel = data;
+-
+-	return io_match_task_safe(req, cancel->task, cancel->all);
+-}
+-
+-static bool io_cancel_defer_files(struct io_ring_ctx *ctx,
+-				  struct task_struct *task, bool cancel_all)
+-{
+-	struct io_defer_entry *de;
+-	LIST_HEAD(list);
+-
+-	spin_lock(&ctx->completion_lock);
+-	list_for_each_entry_reverse(de, &ctx->defer_list, list) {
+-		if (io_match_task_safe(de->req, task, cancel_all)) {
+-			list_cut_position(&list, &ctx->defer_list, &de->list);
+-			break;
+-		}
+-	}
+-	spin_unlock(&ctx->completion_lock);
+-	if (list_empty(&list))
+-		return false;
+-
+-	while (!list_empty(&list)) {
+-		de = list_first_entry(&list, struct io_defer_entry, list);
+-		list_del_init(&de->list);
+-		io_req_complete_failed(de->req, -ECANCELED);
+-		kfree(de);
+-	}
+-	return true;
+-}
+-
+-static bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
+-{
+-	struct io_tctx_node *node;
+-	enum io_wq_cancel cret;
+-	bool ret = false;
+-
+-	mutex_lock(&ctx->uring_lock);
+-	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
+-		struct io_uring_task *tctx = node->task->io_uring;
+-
+-		/*
+-		 * io_wq will stay alive while we hold uring_lock, because it's
+-		 * killed after ctx nodes, which requires to take the lock.
+-		 */
+-		if (!tctx || !tctx->io_wq)
+-			continue;
+-		cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
+-		ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
+-	}
+-	mutex_unlock(&ctx->uring_lock);
+-
+-	return ret;
+-}
+-
+-static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
+-					 struct task_struct *task,
+-					 bool cancel_all)
+-{
+-	struct io_task_cancel cancel = { .task = task, .all = cancel_all, };
+-	struct io_uring_task *tctx = task ? task->io_uring : NULL;
+-
+-	while (1) {
+-		enum io_wq_cancel cret;
+-		bool ret = false;
+-
+-		if (!task) {
+-			ret |= io_uring_try_cancel_iowq(ctx);
+-		} else if (tctx && tctx->io_wq) {
+-			/*
+-			 * Cancels requests of all rings, not only @ctx, but
+-			 * it's fine as the task is in exit/exec.
+-			 */
+-			cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
+-					       &cancel, true);
+-			ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
+-		}
+-
+-		/* SQPOLL thread does its own polling */
+-		if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) ||
+-		    (ctx->sq_data && ctx->sq_data->thread == current)) {
+-			while (!list_empty_careful(&ctx->iopoll_list)) {
+-				io_iopoll_try_reap_events(ctx);
+-				ret = true;
+-			}
+-		}
+-
+-		ret |= io_cancel_defer_files(ctx, task, cancel_all);
+-		ret |= io_poll_remove_all(ctx, task, cancel_all);
+-		ret |= io_kill_timeouts(ctx, task, cancel_all);
+-		if (task)
+-			ret |= io_run_task_work();
+-		if (!ret)
+-			break;
+-		cond_resched();
+-	}
+-}
+-
+-static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
+-{
+-	struct io_uring_task *tctx = current->io_uring;
+-	struct io_tctx_node *node;
+-	int ret;
+-
+-	if (unlikely(!tctx)) {
+-		ret = io_uring_alloc_task_context(current, ctx);
+-		if (unlikely(ret))
+-			return ret;
+-
+-		tctx = current->io_uring;
+-		if (ctx->iowq_limits_set) {
+-			unsigned int limits[2] = { ctx->iowq_limits[0],
+-						   ctx->iowq_limits[1], };
+-
+-			ret = io_wq_max_workers(tctx->io_wq, limits);
+-			if (ret)
+-				return ret;
+-		}
+-	}
+-	if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
+-		node = kmalloc(sizeof(*node), GFP_KERNEL);
+-		if (!node)
+-			return -ENOMEM;
+-		node->ctx = ctx;
+-		node->task = current;
+-
+-		ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
+-					node, GFP_KERNEL));
+-		if (ret) {
+-			kfree(node);
+-			return ret;
+-		}
+-
+-		mutex_lock(&ctx->uring_lock);
+-		list_add(&node->ctx_node, &ctx->tctx_list);
+-		mutex_unlock(&ctx->uring_lock);
+-	}
+-	tctx->last = ctx;
+-	return 0;
+-}
+-
+-/*
+- * Note that this task has used io_uring. We use it for cancelation purposes.
+- */
+-static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
+-{
+-	struct io_uring_task *tctx = current->io_uring;
+-
+-	if (likely(tctx && tctx->last == ctx))
+-		return 0;
+-	return __io_uring_add_tctx_node(ctx);
+-}
+-
+-/*
+- * Remove this io_uring_file -> task mapping.
+- */
+-static void io_uring_del_tctx_node(unsigned long index)
+-{
+-	struct io_uring_task *tctx = current->io_uring;
+-	struct io_tctx_node *node;
+-
+-	if (!tctx)
+-		return;
+-	node = xa_erase(&tctx->xa, index);
+-	if (!node)
+-		return;
+-
+-	WARN_ON_ONCE(current != node->task);
+-	WARN_ON_ONCE(list_empty(&node->ctx_node));
+-
+-	mutex_lock(&node->ctx->uring_lock);
+-	list_del(&node->ctx_node);
+-	mutex_unlock(&node->ctx->uring_lock);
+-
+-	if (tctx->last == node->ctx)
+-		tctx->last = NULL;
+-	kfree(node);
+-}
+-
+-static void io_uring_clean_tctx(struct io_uring_task *tctx)
+-{
+-	struct io_wq *wq = tctx->io_wq;
+-	struct io_tctx_node *node;
+-	unsigned long index;
+-
+-	xa_for_each(&tctx->xa, index, node) {
+-		io_uring_del_tctx_node(index);
+-		cond_resched();
+-	}
+-	if (wq) {
+-		/*
+-		 * Must be after io_uring_del_task_file() (removes nodes under
+-		 * uring_lock) to avoid race with io_uring_try_cancel_iowq().
+-		 */
+-		io_wq_put_and_exit(wq);
+-		tctx->io_wq = NULL;
+-	}
+-}
+-
+-static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
+-{
+-	if (tracked)
+-		return atomic_read(&tctx->inflight_tracked);
+-	return percpu_counter_sum(&tctx->inflight);
+-}
+-
+-/*
+- * Find any io_uring ctx that this task has registered or done IO on, and cancel
+- * requests. @sqd should be not-null IFF it's an SQPOLL thread cancellation.
+- */
+-static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd)
+-{
+-	struct io_uring_task *tctx = current->io_uring;
+-	struct io_ring_ctx *ctx;
+-	s64 inflight;
+-	DEFINE_WAIT(wait);
+-
+-	WARN_ON_ONCE(sqd && sqd->thread != current);
+-
+-	if (!current->io_uring)
+-		return;
+-	if (tctx->io_wq)
+-		io_wq_exit_start(tctx->io_wq);
+-
+-	atomic_inc(&tctx->in_idle);
+-	do {
+-		io_uring_drop_tctx_refs(current);
+-		/* read completions before cancelations */
+-		inflight = tctx_inflight(tctx, !cancel_all);
+-		if (!inflight)
+-			break;
+-
+-		if (!sqd) {
+-			struct io_tctx_node *node;
+-			unsigned long index;
+-
+-			xa_for_each(&tctx->xa, index, node) {
+-				/* sqpoll task will cancel all its requests */
+-				if (node->ctx->sq_data)
+-					continue;
+-				io_uring_try_cancel_requests(node->ctx, current,
+-							     cancel_all);
+-			}
+-		} else {
+-			list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
+-				io_uring_try_cancel_requests(ctx, current,
+-							     cancel_all);
+-		}
+-
+-		prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE);
+-		io_run_task_work();
+-		io_uring_drop_tctx_refs(current);
+-
+-		/*
+-		 * If we've seen completions, retry without waiting. This
+-		 * avoids a race where a completion comes in before we did
+-		 * prepare_to_wait().
+-		 */
+-		if (inflight == tctx_inflight(tctx, !cancel_all))
+-			schedule();
+-		finish_wait(&tctx->wait, &wait);
+-	} while (1);
+-
+-	io_uring_clean_tctx(tctx);
+-	if (cancel_all) {
+-		/*
+-		 * We shouldn't run task_works after cancel, so just leave
+-		 * ->in_idle set for normal exit.
+-		 */
+-		atomic_dec(&tctx->in_idle);
+-		/* for exec all current's requests should be gone, kill tctx */
+-		__io_uring_free(current);
+-	}
+-}
+-
+-void __io_uring_cancel(bool cancel_all)
+-{
+-	io_uring_cancel_generic(cancel_all, NULL);
+-}
+-
+-static void *io_uring_validate_mmap_request(struct file *file,
+-					    loff_t pgoff, size_t sz)
+-{
+-	struct io_ring_ctx *ctx = file->private_data;
+-	loff_t offset = pgoff << PAGE_SHIFT;
+-	struct page *page;
+-	void *ptr;
+-
+-	switch (offset) {
+-	case IORING_OFF_SQ_RING:
+-	case IORING_OFF_CQ_RING:
+-		ptr = ctx->rings;
+-		break;
+-	case IORING_OFF_SQES:
+-		ptr = ctx->sq_sqes;
+-		break;
+-	default:
+-		return ERR_PTR(-EINVAL);
+-	}
+-
+-	page = virt_to_head_page(ptr);
+-	if (sz > page_size(page))
+-		return ERR_PTR(-EINVAL);
+-
+-	return ptr;
+-}
+-
+-#ifdef CONFIG_MMU
+-
+-static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
+-{
+-	size_t sz = vma->vm_end - vma->vm_start;
+-	unsigned long pfn;
+-	void *ptr;
+-
+-	ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
+-	if (IS_ERR(ptr))
+-		return PTR_ERR(ptr);
+-
+-	pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
+-	return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
+-}
+-
+-#else /* !CONFIG_MMU */
+-
+-static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
+-{
+-	return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
+-}
+-
+-static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
+-{
+-	return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
+-}
+-
+-static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
+-	unsigned long addr, unsigned long len,
+-	unsigned long pgoff, unsigned long flags)
+-{
+-	void *ptr;
+-
+-	ptr = io_uring_validate_mmap_request(file, pgoff, len);
+-	if (IS_ERR(ptr))
+-		return PTR_ERR(ptr);
+-
+-	return (unsigned long) ptr;
+-}
+-
+-#endif /* !CONFIG_MMU */
+-
+-static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
+-{
+-	DEFINE_WAIT(wait);
+-
+-	do {
+-		if (!io_sqring_full(ctx))
+-			break;
+-		prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
+-
+-		if (!io_sqring_full(ctx))
+-			break;
+-		schedule();
+-	} while (!signal_pending(current));
+-
+-	finish_wait(&ctx->sqo_sq_wait, &wait);
+-	return 0;
+-}
+-
+-static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
+-			  struct __kernel_timespec __user **ts,
+-			  const sigset_t __user **sig)
+-{
+-	struct io_uring_getevents_arg arg;
+-
+-	/*
+-	 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
+-	 * is just a pointer to the sigset_t.
+-	 */
+-	if (!(flags & IORING_ENTER_EXT_ARG)) {
+-		*sig = (const sigset_t __user *) argp;
+-		*ts = NULL;
+-		return 0;
+-	}
+-
+-	/*
+-	 * EXT_ARG is set - ensure we agree on the size of it and copy in our
+-	 * timespec and sigset_t pointers if good.
+-	 */
+-	if (*argsz != sizeof(arg))
+-		return -EINVAL;
+-	if (copy_from_user(&arg, argp, sizeof(arg)))
+-		return -EFAULT;
+-	if (arg.pad)
+-		return -EINVAL;
+-	*sig = u64_to_user_ptr(arg.sigmask);
+-	*argsz = arg.sigmask_sz;
+-	*ts = u64_to_user_ptr(arg.ts);
+-	return 0;
+-}
+-
+-SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
+-		u32, min_complete, u32, flags, const void __user *, argp,
+-		size_t, argsz)
+-{
+-	struct io_ring_ctx *ctx;
+-	int submitted = 0;
+-	struct fd f;
+-	long ret;
+-
+-	io_run_task_work();
+-
+-	if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
+-			       IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG)))
+-		return -EINVAL;
+-
+-	f = fdget(fd);
+-	if (unlikely(!f.file))
+-		return -EBADF;
+-
+-	ret = -EOPNOTSUPP;
+-	if (unlikely(f.file->f_op != &io_uring_fops))
+-		goto out_fput;
+-
+-	ret = -ENXIO;
+-	ctx = f.file->private_data;
+-	if (unlikely(!percpu_ref_tryget(&ctx->refs)))
+-		goto out_fput;
+-
+-	ret = -EBADFD;
+-	if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED))
+-		goto out;
+-
+-	/*
+-	 * For SQ polling, the thread will do all submissions and completions.
+-	 * Just return the requested submit count, and wake the thread if
+-	 * we were asked to.
+-	 */
+-	ret = 0;
+-	if (ctx->flags & IORING_SETUP_SQPOLL) {
+-		io_cqring_overflow_flush(ctx);
+-
+-		if (unlikely(ctx->sq_data->thread == NULL)) {
+-			ret = -EOWNERDEAD;
+-			goto out;
+-		}
+-		if (flags & IORING_ENTER_SQ_WAKEUP)
+-			wake_up(&ctx->sq_data->wait);
+-		if (flags & IORING_ENTER_SQ_WAIT) {
+-			ret = io_sqpoll_wait_sq(ctx);
+-			if (ret)
+-				goto out;
+-		}
+-		submitted = to_submit;
+-	} else if (to_submit) {
+-		ret = io_uring_add_tctx_node(ctx);
+-		if (unlikely(ret))
+-			goto out;
+-		mutex_lock(&ctx->uring_lock);
+-		submitted = io_submit_sqes(ctx, to_submit);
+-		mutex_unlock(&ctx->uring_lock);
+-
+-		if (submitted != to_submit)
+-			goto out;
+-	}
+-	if (flags & IORING_ENTER_GETEVENTS) {
+-		const sigset_t __user *sig;
+-		struct __kernel_timespec __user *ts;
+-
+-		ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
+-		if (unlikely(ret))
+-			goto out;
+-
+-		min_complete = min(min_complete, ctx->cq_entries);
+-
+-		/*
+-		 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
+-		 * space applications don't need to do io completion events
+-		 * polling again, they can rely on io_sq_thread to do polling
+-		 * work, which can reduce cpu usage and uring_lock contention.
+-		 */
+-		if (ctx->flags & IORING_SETUP_IOPOLL &&
+-		    !(ctx->flags & IORING_SETUP_SQPOLL)) {
+-			ret = io_iopoll_check(ctx, min_complete);
+-		} else {
+-			ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts);
+-		}
+-	}
+-
+-out:
+-	percpu_ref_put(&ctx->refs);
+-out_fput:
+-	fdput(f);
+-	return submitted ? submitted : ret;
+-}
+-
+-#ifdef CONFIG_PROC_FS
+-static int io_uring_show_cred(struct seq_file *m, unsigned int id,
+-		const struct cred *cred)
+-{
+-	struct user_namespace *uns = seq_user_ns(m);
+-	struct group_info *gi;
+-	kernel_cap_t cap;
+-	unsigned __capi;
+-	int g;
+-
+-	seq_printf(m, "%5d\n", id);
+-	seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
+-	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
+-	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
+-	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
+-	seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
+-	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
+-	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
+-	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
+-	seq_puts(m, "\n\tGroups:\t");
+-	gi = cred->group_info;
+-	for (g = 0; g < gi->ngroups; g++) {
+-		seq_put_decimal_ull(m, g ? " " : "",
+-					from_kgid_munged(uns, gi->gid[g]));
+-	}
+-	seq_puts(m, "\n\tCapEff:\t");
+-	cap = cred->cap_effective;
+-	CAP_FOR_EACH_U32(__capi)
+-		seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
+-	seq_putc(m, '\n');
+-	return 0;
+-}
+-
+-static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
+-{
+-	struct io_sq_data *sq = NULL;
+-	bool has_lock;
+-	int i;
+-
+-	/*
+-	 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
+-	 * since fdinfo case grabs it in the opposite direction of normal use
+-	 * cases. If we fail to get the lock, we just don't iterate any
+-	 * structures that could be going away outside the io_uring mutex.
+-	 */
+-	has_lock = mutex_trylock(&ctx->uring_lock);
+-
+-	if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
+-		sq = ctx->sq_data;
+-		if (!sq->thread)
+-			sq = NULL;
+-	}
+-
+-	seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
+-	seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
+-	seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
+-	for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
+-		struct file *f = io_file_from_index(ctx, i);
+-
+-		if (f)
+-			seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
+-		else
+-			seq_printf(m, "%5u: <none>\n", i);
+-	}
+-	seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
+-	for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
+-		struct io_mapped_ubuf *buf = ctx->user_bufs[i];
+-		unsigned int len = buf->ubuf_end - buf->ubuf;
+-
+-		seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
+-	}
+-	if (has_lock && !xa_empty(&ctx->personalities)) {
+-		unsigned long index;
+-		const struct cred *cred;
+-
+-		seq_printf(m, "Personalities:\n");
+-		xa_for_each(&ctx->personalities, index, cred)
+-			io_uring_show_cred(m, index, cred);
+-	}
+-	seq_printf(m, "PollList:\n");
+-	spin_lock(&ctx->completion_lock);
+-	for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
+-		struct hlist_head *list = &ctx->cancel_hash[i];
+-		struct io_kiocb *req;
+-
+-		hlist_for_each_entry(req, list, hash_node)
+-			seq_printf(m, "  op=%d, task_works=%d\n", req->opcode,
+-					req->task->task_works != NULL);
+-	}
+-	spin_unlock(&ctx->completion_lock);
+-	if (has_lock)
+-		mutex_unlock(&ctx->uring_lock);
+-}
+-
+-static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
+-{
+-	struct io_ring_ctx *ctx = f->private_data;
+-
+-	if (percpu_ref_tryget(&ctx->refs)) {
+-		__io_uring_show_fdinfo(ctx, m);
+-		percpu_ref_put(&ctx->refs);
+-	}
+-}
+-#endif
+-
+-static const struct file_operations io_uring_fops = {
+-	.release	= io_uring_release,
+-	.mmap		= io_uring_mmap,
+-#ifndef CONFIG_MMU
+-	.get_unmapped_area = io_uring_nommu_get_unmapped_area,
+-	.mmap_capabilities = io_uring_nommu_mmap_capabilities,
+-#endif
+-	.poll		= io_uring_poll,
+-#ifdef CONFIG_PROC_FS
+-	.show_fdinfo	= io_uring_show_fdinfo,
+-#endif
+-};
+-
+-static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
+-				  struct io_uring_params *p)
+-{
+-	struct io_rings *rings;
+-	size_t size, sq_array_offset;
+-
+-	/* make sure these are sane, as we already accounted them */
+-	ctx->sq_entries = p->sq_entries;
+-	ctx->cq_entries = p->cq_entries;
+-
+-	size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
+-	if (size == SIZE_MAX)
+-		return -EOVERFLOW;
+-
+-	rings = io_mem_alloc(size);
+-	if (!rings)
+-		return -ENOMEM;
+-
+-	ctx->rings = rings;
+-	ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
+-	rings->sq_ring_mask = p->sq_entries - 1;
+-	rings->cq_ring_mask = p->cq_entries - 1;
+-	rings->sq_ring_entries = p->sq_entries;
+-	rings->cq_ring_entries = p->cq_entries;
+-
+-	size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
+-	if (size == SIZE_MAX) {
+-		io_mem_free(ctx->rings);
+-		ctx->rings = NULL;
+-		return -EOVERFLOW;
+-	}
+-
+-	ctx->sq_sqes = io_mem_alloc(size);
+-	if (!ctx->sq_sqes) {
+-		io_mem_free(ctx->rings);
+-		ctx->rings = NULL;
+-		return -ENOMEM;
+-	}
+-
+-	return 0;
+-}
+-
+-static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
+-{
+-	int ret, fd;
+-
+-	fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
+-	if (fd < 0)
+-		return fd;
+-
+-	ret = io_uring_add_tctx_node(ctx);
+-	if (ret) {
+-		put_unused_fd(fd);
+-		return ret;
+-	}
+-	fd_install(fd, file);
+-	return fd;
+-}
+-
+-/*
+- * Allocate an anonymous fd, this is what constitutes the application
+- * visible backing of an io_uring instance. The application mmaps this
+- * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
+- * we have to tie this fd to a socket for file garbage collection purposes.
+- */
+-static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
+-{
+-	struct file *file;
+-#if defined(CONFIG_UNIX)
+-	int ret;
+-
+-	ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
+-				&ctx->ring_sock);
+-	if (ret)
+-		return ERR_PTR(ret);
+-#endif
+-
+-	file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
+-					O_RDWR | O_CLOEXEC);
+-#if defined(CONFIG_UNIX)
+-	if (IS_ERR(file)) {
+-		sock_release(ctx->ring_sock);
+-		ctx->ring_sock = NULL;
+-	} else {
+-		ctx->ring_sock->file = file;
+-	}
+-#endif
+-	return file;
+-}
+-
+-static int io_uring_create(unsigned entries, struct io_uring_params *p,
+-			   struct io_uring_params __user *params)
+-{
+-	struct io_ring_ctx *ctx;
+-	struct file *file;
+-	int ret;
+-
+-	if (!entries)
+-		return -EINVAL;
+-	if (entries > IORING_MAX_ENTRIES) {
+-		if (!(p->flags & IORING_SETUP_CLAMP))
+-			return -EINVAL;
+-		entries = IORING_MAX_ENTRIES;
+-	}
+-
+-	/*
+-	 * Use twice as many entries for the CQ ring. It's possible for the
+-	 * application to drive a higher depth than the size of the SQ ring,
+-	 * since the sqes are only used at submission time. This allows for
+-	 * some flexibility in overcommitting a bit. If the application has
+-	 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
+-	 * of CQ ring entries manually.
+-	 */
+-	p->sq_entries = roundup_pow_of_two(entries);
+-	if (p->flags & IORING_SETUP_CQSIZE) {
+-		/*
+-		 * If IORING_SETUP_CQSIZE is set, we do the same roundup
+-		 * to a power-of-two, if it isn't already. We do NOT impose
+-		 * any cq vs sq ring sizing.
+-		 */
+-		if (!p->cq_entries)
+-			return -EINVAL;
+-		if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
+-			if (!(p->flags & IORING_SETUP_CLAMP))
+-				return -EINVAL;
+-			p->cq_entries = IORING_MAX_CQ_ENTRIES;
+-		}
+-		p->cq_entries = roundup_pow_of_two(p->cq_entries);
+-		if (p->cq_entries < p->sq_entries)
+-			return -EINVAL;
+-	} else {
+-		p->cq_entries = 2 * p->sq_entries;
+-	}
+-
+-	ctx = io_ring_ctx_alloc(p);
+-	if (!ctx)
+-		return -ENOMEM;
+-	ctx->compat = in_compat_syscall();
+-	if (!capable(CAP_IPC_LOCK))
+-		ctx->user = get_uid(current_user());
+-
+-	/*
+-	 * This is just grabbed for accounting purposes. When a process exits,
+-	 * the mm is exited and dropped before the files, hence we need to hang
+-	 * on to this mm purely for the purposes of being able to unaccount
+-	 * memory (locked/pinned vm). It's not used for anything else.
+-	 */
+-	mmgrab(current->mm);
+-	ctx->mm_account = current->mm;
+-
+-	ret = io_allocate_scq_urings(ctx, p);
+-	if (ret)
+-		goto err;
+-
+-	ret = io_sq_offload_create(ctx, p);
+-	if (ret)
+-		goto err;
+-	/* always set a rsrc node */
+-	ret = io_rsrc_node_switch_start(ctx);
+-	if (ret)
+-		goto err;
+-	io_rsrc_node_switch(ctx, NULL);
+-
+-	memset(&p->sq_off, 0, sizeof(p->sq_off));
+-	p->sq_off.head = offsetof(struct io_rings, sq.head);
+-	p->sq_off.tail = offsetof(struct io_rings, sq.tail);
+-	p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
+-	p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
+-	p->sq_off.flags = offsetof(struct io_rings, sq_flags);
+-	p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
+-	p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
+-
+-	memset(&p->cq_off, 0, sizeof(p->cq_off));
+-	p->cq_off.head = offsetof(struct io_rings, cq.head);
+-	p->cq_off.tail = offsetof(struct io_rings, cq.tail);
+-	p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
+-	p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
+-	p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
+-	p->cq_off.cqes = offsetof(struct io_rings, cqes);
+-	p->cq_off.flags = offsetof(struct io_rings, cq_flags);
+-
+-	p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
+-			IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
+-			IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
+-			IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
+-			IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS |
+-			IORING_FEAT_RSRC_TAGS;
+-
+-	if (copy_to_user(params, p, sizeof(*p))) {
+-		ret = -EFAULT;
+-		goto err;
+-	}
+-
+-	file = io_uring_get_file(ctx);
+-	if (IS_ERR(file)) {
+-		ret = PTR_ERR(file);
+-		goto err;
+-	}
+-
+-	/*
+-	 * Install ring fd as the very last thing, so we don't risk someone
+-	 * having closed it before we finish setup
+-	 */
+-	ret = io_uring_install_fd(ctx, file);
+-	if (ret < 0) {
+-		/* fput will clean it up */
+-		fput(file);
+-		return ret;
+-	}
+-
+-	trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
+-	return ret;
+-err:
+-	io_ring_ctx_wait_and_kill(ctx);
+-	return ret;
+-}
+-
+-/*
+- * Sets up an aio uring context, and returns the fd. Applications asks for a
+- * ring size, we return the actual sq/cq ring sizes (among other things) in the
+- * params structure passed in.
+- */
+-static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
+-{
+-	struct io_uring_params p;
+-	int i;
+-
+-	if (copy_from_user(&p, params, sizeof(p)))
+-		return -EFAULT;
+-	for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
+-		if (p.resv[i])
+-			return -EINVAL;
+-	}
+-
+-	if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
+-			IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
+-			IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
+-			IORING_SETUP_R_DISABLED))
+-		return -EINVAL;
+-
+-	return  io_uring_create(entries, &p, params);
+-}
+-
+-SYSCALL_DEFINE2(io_uring_setup, u32, entries,
+-		struct io_uring_params __user *, params)
+-{
+-	return io_uring_setup(entries, params);
+-}
+-
+-static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
+-{
+-	struct io_uring_probe *p;
+-	size_t size;
+-	int i, ret;
+-
+-	size = struct_size(p, ops, nr_args);
+-	if (size == SIZE_MAX)
+-		return -EOVERFLOW;
+-	p = kzalloc(size, GFP_KERNEL);
+-	if (!p)
+-		return -ENOMEM;
+-
+-	ret = -EFAULT;
+-	if (copy_from_user(p, arg, size))
+-		goto out;
+-	ret = -EINVAL;
+-	if (memchr_inv(p, 0, size))
+-		goto out;
+-
+-	p->last_op = IORING_OP_LAST - 1;
+-	if (nr_args > IORING_OP_LAST)
+-		nr_args = IORING_OP_LAST;
+-
+-	for (i = 0; i < nr_args; i++) {
+-		p->ops[i].op = i;
+-		if (!io_op_defs[i].not_supported)
+-			p->ops[i].flags = IO_URING_OP_SUPPORTED;
+-	}
+-	p->ops_len = i;
+-
+-	ret = 0;
+-	if (copy_to_user(arg, p, size))
+-		ret = -EFAULT;
+-out:
+-	kfree(p);
+-	return ret;
+-}
+-
+-static int io_register_personality(struct io_ring_ctx *ctx)
+-{
+-	const struct cred *creds;
+-	u32 id;
+-	int ret;
+-
+-	creds = get_current_cred();
+-
+-	ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
+-			XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
+-	if (ret < 0) {
+-		put_cred(creds);
+-		return ret;
+-	}
+-	return id;
+-}
+-
+-static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
+-				    unsigned int nr_args)
+-{
+-	struct io_uring_restriction *res;
+-	size_t size;
+-	int i, ret;
+-
+-	/* Restrictions allowed only if rings started disabled */
+-	if (!(ctx->flags & IORING_SETUP_R_DISABLED))
+-		return -EBADFD;
+-
+-	/* We allow only a single restrictions registration */
+-	if (ctx->restrictions.registered)
+-		return -EBUSY;
+-
+-	if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
+-		return -EINVAL;
+-
+-	size = array_size(nr_args, sizeof(*res));
+-	if (size == SIZE_MAX)
+-		return -EOVERFLOW;
+-
+-	res = memdup_user(arg, size);
+-	if (IS_ERR(res))
+-		return PTR_ERR(res);
+-
+-	ret = 0;
+-
+-	for (i = 0; i < nr_args; i++) {
+-		switch (res[i].opcode) {
+-		case IORING_RESTRICTION_REGISTER_OP:
+-			if (res[i].register_op >= IORING_REGISTER_LAST) {
+-				ret = -EINVAL;
+-				goto out;
+-			}
+-
+-			__set_bit(res[i].register_op,
+-				  ctx->restrictions.register_op);
+-			break;
+-		case IORING_RESTRICTION_SQE_OP:
+-			if (res[i].sqe_op >= IORING_OP_LAST) {
+-				ret = -EINVAL;
+-				goto out;
+-			}
+-
+-			__set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
+-			break;
+-		case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
+-			ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
+-			break;
+-		case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
+-			ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
+-			break;
+-		default:
+-			ret = -EINVAL;
+-			goto out;
+-		}
+-	}
+-
+-out:
+-	/* Reset all restrictions if an error happened */
+-	if (ret != 0)
+-		memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
+-	else
+-		ctx->restrictions.registered = true;
+-
+-	kfree(res);
+-	return ret;
+-}
+-
+-static int io_register_enable_rings(struct io_ring_ctx *ctx)
+-{
+-	if (!(ctx->flags & IORING_SETUP_R_DISABLED))
+-		return -EBADFD;
+-
+-	if (ctx->restrictions.registered)
+-		ctx->restricted = 1;
+-
+-	ctx->flags &= ~IORING_SETUP_R_DISABLED;
+-	if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
+-		wake_up(&ctx->sq_data->wait);
+-	return 0;
+-}
+-
+-static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
+-				     struct io_uring_rsrc_update2 *up,
+-				     unsigned nr_args)
+-{
+-	__u32 tmp;
+-	int err;
+-
+-	if (check_add_overflow(up->offset, nr_args, &tmp))
+-		return -EOVERFLOW;
+-	err = io_rsrc_node_switch_start(ctx);
+-	if (err)
+-		return err;
+-
+-	switch (type) {
+-	case IORING_RSRC_FILE:
+-		return __io_sqe_files_update(ctx, up, nr_args);
+-	case IORING_RSRC_BUFFER:
+-		return __io_sqe_buffers_update(ctx, up, nr_args);
+-	}
+-	return -EINVAL;
+-}
+-
+-static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
+-				    unsigned nr_args)
+-{
+-	struct io_uring_rsrc_update2 up;
+-
+-	if (!nr_args)
+-		return -EINVAL;
+-	memset(&up, 0, sizeof(up));
+-	if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update)))
+-		return -EFAULT;
+-	if (up.resv || up.resv2)
+-		return -EINVAL;
+-	return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args);
+-}
+-
+-static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
+-				   unsigned size, unsigned type)
+-{
+-	struct io_uring_rsrc_update2 up;
+-
+-	if (size != sizeof(up))
+-		return -EINVAL;
+-	if (copy_from_user(&up, arg, sizeof(up)))
+-		return -EFAULT;
+-	if (!up.nr || up.resv || up.resv2)
+-		return -EINVAL;
+-	return __io_register_rsrc_update(ctx, type, &up, up.nr);
+-}
+-
+-static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
+-			    unsigned int size, unsigned int type)
+-{
+-	struct io_uring_rsrc_register rr;
+-
+-	/* keep it extendible */
+-	if (size != sizeof(rr))
+-		return -EINVAL;
+-
+-	memset(&rr, 0, sizeof(rr));
+-	if (copy_from_user(&rr, arg, size))
+-		return -EFAULT;
+-	if (!rr.nr || rr.resv || rr.resv2)
+-		return -EINVAL;
+-
+-	switch (type) {
+-	case IORING_RSRC_FILE:
+-		return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data),
+-					     rr.nr, u64_to_user_ptr(rr.tags));
+-	case IORING_RSRC_BUFFER:
+-		return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data),
+-					       rr.nr, u64_to_user_ptr(rr.tags));
+-	}
+-	return -EINVAL;
+-}
+-
+-static int io_register_iowq_aff(struct io_ring_ctx *ctx, void __user *arg,
+-				unsigned len)
+-{
+-	struct io_uring_task *tctx = current->io_uring;
+-	cpumask_var_t new_mask;
+-	int ret;
+-
+-	if (!tctx || !tctx->io_wq)
+-		return -EINVAL;
+-
+-	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
+-		return -ENOMEM;
+-
+-	cpumask_clear(new_mask);
+-	if (len > cpumask_size())
+-		len = cpumask_size();
+-
+-	if (in_compat_syscall()) {
+-		ret = compat_get_bitmap(cpumask_bits(new_mask),
+-					(const compat_ulong_t __user *)arg,
+-					len * 8 /* CHAR_BIT */);
+-	} else {
+-		ret = copy_from_user(new_mask, arg, len);
+-	}
+-
+-	if (ret) {
+-		free_cpumask_var(new_mask);
+-		return -EFAULT;
+-	}
+-
+-	ret = io_wq_cpu_affinity(tctx->io_wq, new_mask);
+-	free_cpumask_var(new_mask);
+-	return ret;
+-}
+-
+-static int io_unregister_iowq_aff(struct io_ring_ctx *ctx)
+-{
+-	struct io_uring_task *tctx = current->io_uring;
+-
+-	if (!tctx || !tctx->io_wq)
+-		return -EINVAL;
+-
+-	return io_wq_cpu_affinity(tctx->io_wq, NULL);
+-}
+-
+-static int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
+-					void __user *arg)
+-	__must_hold(&ctx->uring_lock)
+-{
+-	struct io_tctx_node *node;
+-	struct io_uring_task *tctx = NULL;
+-	struct io_sq_data *sqd = NULL;
+-	__u32 new_count[2];
+-	int i, ret;
+-
+-	if (copy_from_user(new_count, arg, sizeof(new_count)))
+-		return -EFAULT;
+-	for (i = 0; i < ARRAY_SIZE(new_count); i++)
+-		if (new_count[i] > INT_MAX)
+-			return -EINVAL;
+-
+-	if (ctx->flags & IORING_SETUP_SQPOLL) {
+-		sqd = ctx->sq_data;
+-		if (sqd) {
+-			/*
+-			 * Observe the correct sqd->lock -> ctx->uring_lock
+-			 * ordering. Fine to drop uring_lock here, we hold
+-			 * a ref to the ctx.
+-			 */
+-			refcount_inc(&sqd->refs);
+-			mutex_unlock(&ctx->uring_lock);
+-			mutex_lock(&sqd->lock);
+-			mutex_lock(&ctx->uring_lock);
+-			if (sqd->thread)
+-				tctx = sqd->thread->io_uring;
+-		}
+-	} else {
+-		tctx = current->io_uring;
+-	}
+-
+-	BUILD_BUG_ON(sizeof(new_count) != sizeof(ctx->iowq_limits));
+-
+-	for (i = 0; i < ARRAY_SIZE(new_count); i++)
+-		if (new_count[i])
+-			ctx->iowq_limits[i] = new_count[i];
+-	ctx->iowq_limits_set = true;
+-
+-	ret = -EINVAL;
+-	if (tctx && tctx->io_wq) {
+-		ret = io_wq_max_workers(tctx->io_wq, new_count);
+-		if (ret)
+-			goto err;
+-	} else {
+-		memset(new_count, 0, sizeof(new_count));
+-	}
+-
+-	if (sqd) {
+-		mutex_unlock(&sqd->lock);
+-		io_put_sq_data(sqd);
+-	}
+-
+-	if (copy_to_user(arg, new_count, sizeof(new_count)))
+-		return -EFAULT;
+-
+-	/* that's it for SQPOLL, only the SQPOLL task creates requests */
+-	if (sqd)
+-		return 0;
+-
+-	/* now propagate the restriction to all registered users */
+-	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
+-		struct io_uring_task *tctx = node->task->io_uring;
+-
+-		if (WARN_ON_ONCE(!tctx->io_wq))
+-			continue;
+-
+-		for (i = 0; i < ARRAY_SIZE(new_count); i++)
+-			new_count[i] = ctx->iowq_limits[i];
+-		/* ignore errors, it always returns zero anyway */
+-		(void)io_wq_max_workers(tctx->io_wq, new_count);
+-	}
+-	return 0;
+-err:
+-	if (sqd) {
+-		mutex_unlock(&sqd->lock);
+-		io_put_sq_data(sqd);
+-	}
+-	return ret;
+-}
+-
+-static bool io_register_op_must_quiesce(int op)
+-{
+-	switch (op) {
+-	case IORING_REGISTER_BUFFERS:
+-	case IORING_UNREGISTER_BUFFERS:
+-	case IORING_REGISTER_FILES:
+-	case IORING_UNREGISTER_FILES:
+-	case IORING_REGISTER_FILES_UPDATE:
+-	case IORING_REGISTER_PROBE:
+-	case IORING_REGISTER_PERSONALITY:
+-	case IORING_UNREGISTER_PERSONALITY:
+-	case IORING_REGISTER_FILES2:
+-	case IORING_REGISTER_FILES_UPDATE2:
+-	case IORING_REGISTER_BUFFERS2:
+-	case IORING_REGISTER_BUFFERS_UPDATE:
+-	case IORING_REGISTER_IOWQ_AFF:
+-	case IORING_UNREGISTER_IOWQ_AFF:
+-	case IORING_REGISTER_IOWQ_MAX_WORKERS:
+-		return false;
+-	default:
+-		return true;
+-	}
+-}
+-
+-static int io_ctx_quiesce(struct io_ring_ctx *ctx)
+-{
+-	long ret;
+-
+-	percpu_ref_kill(&ctx->refs);
+-
+-	/*
+-	 * Drop uring mutex before waiting for references to exit. If another
+-	 * thread is currently inside io_uring_enter() it might need to grab the
+-	 * uring_lock to make progress. If we hold it here across the drain
+-	 * wait, then we can deadlock. It's safe to drop the mutex here, since
+-	 * no new references will come in after we've killed the percpu ref.
+-	 */
+-	mutex_unlock(&ctx->uring_lock);
+-	do {
+-		ret = wait_for_completion_interruptible(&ctx->ref_comp);
+-		if (!ret)
+-			break;
+-		ret = io_run_task_work_sig();
+-	} while (ret >= 0);
+-	mutex_lock(&ctx->uring_lock);
+-
+-	if (ret)
+-		io_refs_resurrect(&ctx->refs, &ctx->ref_comp);
+-	return ret;
+-}
+-
+-static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
+-			       void __user *arg, unsigned nr_args)
+-	__releases(ctx->uring_lock)
+-	__acquires(ctx->uring_lock)
+-{
+-	int ret;
+-
+-	/*
+-	 * We're inside the ring mutex, if the ref is already dying, then
+-	 * someone else killed the ctx or is already going through
+-	 * io_uring_register().
+-	 */
+-	if (percpu_ref_is_dying(&ctx->refs))
+-		return -ENXIO;
+-
+-	if (ctx->restricted) {
+-		if (opcode >= IORING_REGISTER_LAST)
+-			return -EINVAL;
+-		opcode = array_index_nospec(opcode, IORING_REGISTER_LAST);
+-		if (!test_bit(opcode, ctx->restrictions.register_op))
+-			return -EACCES;
+-	}
+-
+-	if (io_register_op_must_quiesce(opcode)) {
+-		ret = io_ctx_quiesce(ctx);
+-		if (ret)
+-			return ret;
+-	}
+-
+-	switch (opcode) {
+-	case IORING_REGISTER_BUFFERS:
+-		ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL);
+-		break;
+-	case IORING_UNREGISTER_BUFFERS:
+-		ret = -EINVAL;
+-		if (arg || nr_args)
+-			break;
+-		ret = io_sqe_buffers_unregister(ctx);
+-		break;
+-	case IORING_REGISTER_FILES:
+-		ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
+-		break;
+-	case IORING_UNREGISTER_FILES:
+-		ret = -EINVAL;
+-		if (arg || nr_args)
+-			break;
+-		ret = io_sqe_files_unregister(ctx);
+-		break;
+-	case IORING_REGISTER_FILES_UPDATE:
+-		ret = io_register_files_update(ctx, arg, nr_args);
+-		break;
+-	case IORING_REGISTER_EVENTFD:
+-	case IORING_REGISTER_EVENTFD_ASYNC:
+-		ret = -EINVAL;
+-		if (nr_args != 1)
+-			break;
+-		ret = io_eventfd_register(ctx, arg);
+-		if (ret)
+-			break;
+-		if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
+-			ctx->eventfd_async = 1;
+-		else
+-			ctx->eventfd_async = 0;
+-		break;
+-	case IORING_UNREGISTER_EVENTFD:
+-		ret = -EINVAL;
+-		if (arg || nr_args)
+-			break;
+-		ret = io_eventfd_unregister(ctx);
+-		break;
+-	case IORING_REGISTER_PROBE:
+-		ret = -EINVAL;
+-		if (!arg || nr_args > 256)
+-			break;
+-		ret = io_probe(ctx, arg, nr_args);
+-		break;
+-	case IORING_REGISTER_PERSONALITY:
+-		ret = -EINVAL;
+-		if (arg || nr_args)
+-			break;
+-		ret = io_register_personality(ctx);
+-		break;
+-	case IORING_UNREGISTER_PERSONALITY:
+-		ret = -EINVAL;
+-		if (arg)
+-			break;
+-		ret = io_unregister_personality(ctx, nr_args);
+-		break;
+-	case IORING_REGISTER_ENABLE_RINGS:
+-		ret = -EINVAL;
+-		if (arg || nr_args)
+-			break;
+-		ret = io_register_enable_rings(ctx);
+-		break;
+-	case IORING_REGISTER_RESTRICTIONS:
+-		ret = io_register_restrictions(ctx, arg, nr_args);
+-		break;
+-	case IORING_REGISTER_FILES2:
+-		ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE);
+-		break;
+-	case IORING_REGISTER_FILES_UPDATE2:
+-		ret = io_register_rsrc_update(ctx, arg, nr_args,
+-					      IORING_RSRC_FILE);
+-		break;
+-	case IORING_REGISTER_BUFFERS2:
+-		ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER);
+-		break;
+-	case IORING_REGISTER_BUFFERS_UPDATE:
+-		ret = io_register_rsrc_update(ctx, arg, nr_args,
+-					      IORING_RSRC_BUFFER);
+-		break;
+-	case IORING_REGISTER_IOWQ_AFF:
+-		ret = -EINVAL;
+-		if (!arg || !nr_args)
+-			break;
+-		ret = io_register_iowq_aff(ctx, arg, nr_args);
+-		break;
+-	case IORING_UNREGISTER_IOWQ_AFF:
+-		ret = -EINVAL;
+-		if (arg || nr_args)
+-			break;
+-		ret = io_unregister_iowq_aff(ctx);
+-		break;
+-	case IORING_REGISTER_IOWQ_MAX_WORKERS:
+-		ret = -EINVAL;
+-		if (!arg || nr_args != 2)
+-			break;
+-		ret = io_register_iowq_max_workers(ctx, arg);
+-		break;
+-	default:
+-		ret = -EINVAL;
+-		break;
+-	}
+-
+-	if (io_register_op_must_quiesce(opcode)) {
+-		/* bring the ctx back to life */
+-		percpu_ref_reinit(&ctx->refs);
+-		reinit_completion(&ctx->ref_comp);
+-	}
+-	return ret;
+-}
+-
+-SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
+-		void __user *, arg, unsigned int, nr_args)
+-{
+-	struct io_ring_ctx *ctx;
+-	long ret = -EBADF;
+-	struct fd f;
+-
+-	f = fdget(fd);
+-	if (!f.file)
+-		return -EBADF;
+-
+-	ret = -EOPNOTSUPP;
+-	if (f.file->f_op != &io_uring_fops)
+-		goto out_fput;
+-
+-	ctx = f.file->private_data;
+-
+-	io_run_task_work();
+-
+-	mutex_lock(&ctx->uring_lock);
+-	ret = __io_uring_register(ctx, opcode, arg, nr_args);
+-	mutex_unlock(&ctx->uring_lock);
+-	trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
+-							ctx->cq_ev_fd != NULL, ret);
+-out_fput:
+-	fdput(f);
+-	return ret;
+-}
+-
+-static int __init io_uring_init(void)
+-{
+-#define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
+-	BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
+-	BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
+-} while (0)
+-
+-#define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
+-	__BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
+-	BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
+-	BUILD_BUG_SQE_ELEM(0,  __u8,   opcode);
+-	BUILD_BUG_SQE_ELEM(1,  __u8,   flags);
+-	BUILD_BUG_SQE_ELEM(2,  __u16,  ioprio);
+-	BUILD_BUG_SQE_ELEM(4,  __s32,  fd);
+-	BUILD_BUG_SQE_ELEM(8,  __u64,  off);
+-	BUILD_BUG_SQE_ELEM(8,  __u64,  addr2);
+-	BUILD_BUG_SQE_ELEM(16, __u64,  addr);
+-	BUILD_BUG_SQE_ELEM(16, __u64,  splice_off_in);
+-	BUILD_BUG_SQE_ELEM(24, __u32,  len);
+-	BUILD_BUG_SQE_ELEM(28,     __kernel_rwf_t, rw_flags);
+-	BUILD_BUG_SQE_ELEM(28, /* compat */   int, rw_flags);
+-	BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  fsync_flags);
+-	BUILD_BUG_SQE_ELEM(28, /* compat */ __u16,  poll_events);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  poll32_events);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  sync_range_flags);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  msg_flags);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  timeout_flags);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  accept_flags);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  cancel_flags);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  open_flags);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  statx_flags);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  fadvise_advice);
+-	BUILD_BUG_SQE_ELEM(28, __u32,  splice_flags);
+-	BUILD_BUG_SQE_ELEM(32, __u64,  user_data);
+-	BUILD_BUG_SQE_ELEM(40, __u16,  buf_index);
+-	BUILD_BUG_SQE_ELEM(40, __u16,  buf_group);
+-	BUILD_BUG_SQE_ELEM(42, __u16,  personality);
+-	BUILD_BUG_SQE_ELEM(44, __s32,  splice_fd_in);
+-	BUILD_BUG_SQE_ELEM(44, __u32,  file_index);
+-
+-	BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=
+-		     sizeof(struct io_uring_rsrc_update));
+-	BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) >
+-		     sizeof(struct io_uring_rsrc_update2));
+-
+-	/* ->buf_index is u16 */
+-	BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16));
+-
+-	/* should fit into one byte */
+-	BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));
+-
+-	BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
+-	BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int));
+-
+-	req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
+-				SLAB_ACCOUNT);
+-	return 0;
+-};
+-__initcall(io_uring_init);
+diff --git a/include/asm-generic/tlb.h b/include/asm-generic/tlb.h
+index 71942a1c642d4..c99710b3027a0 100644
+--- a/include/asm-generic/tlb.h
++++ b/include/asm-generic/tlb.h
+@@ -207,12 +207,16 @@ extern void tlb_remove_table(struct mmu_gather *tlb, void *table);
+ #define tlb_needs_table_invalidate() (true)
+ #endif
+ 
++void tlb_remove_table_sync_one(void);
++
+ #else
+ 
+ #ifdef tlb_needs_table_invalidate
+ #error tlb_needs_table_invalidate() requires MMU_GATHER_RCU_TABLE_FREE
+ #endif
+ 
++static inline void tlb_remove_table_sync_one(void) { }
++
+ #endif /* CONFIG_MMU_GATHER_RCU_TABLE_FREE */
+ 
+ 
+diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
+index 75c151413fda8..45cdb12243e3f 100644
+--- a/include/linux/cgroup.h
++++ b/include/linux/cgroup.h
+@@ -68,6 +68,7 @@ struct css_task_iter {
+ 	struct list_head		iters_node;	/* css_set->task_iters */
+ };
+ 
++extern struct file_system_type cgroup_fs_type;
+ extern struct cgroup_root cgrp_dfl_root;
+ extern struct css_set init_css_set;
+ 
+diff --git a/include/linux/clk.h b/include/linux/clk.h
+index 266e8de3cb515..e280e0acb55c6 100644
+--- a/include/linux/clk.h
++++ b/include/linux/clk.h
+@@ -458,6 +458,47 @@ int __must_check devm_clk_bulk_get_all(struct device *dev,
+  */
+ struct clk *devm_clk_get(struct device *dev, const char *id);
+ 
++/**
++ * devm_clk_get_prepared - devm_clk_get() + clk_prepare()
++ * @dev: device for clock "consumer"
++ * @id: clock consumer ID
++ *
++ * Context: May sleep.
++ *
++ * Return: a struct clk corresponding to the clock producer, or
++ * valid IS_ERR() condition containing errno.  The implementation
++ * uses @dev and @id to determine the clock consumer, and thereby
++ * the clock producer.  (IOW, @id may be identical strings, but
++ * clk_get may return different clock producers depending on @dev.)
++ *
++ * The returned clk (if valid) is prepared. Drivers must however assume
++ * that the clock is not enabled.
++ *
++ * The clock will automatically be unprepared and freed when the device
++ * is unbound from the bus.
++ */
++struct clk *devm_clk_get_prepared(struct device *dev, const char *id);
++
++/**
++ * devm_clk_get_enabled - devm_clk_get() + clk_prepare_enable()
++ * @dev: device for clock "consumer"
++ * @id: clock consumer ID
++ *
++ * Context: May sleep.
++ *
++ * Return: a struct clk corresponding to the clock producer, or
++ * valid IS_ERR() condition containing errno.  The implementation
++ * uses @dev and @id to determine the clock consumer, and thereby
++ * the clock producer.  (IOW, @id may be identical strings, but
++ * clk_get may return different clock producers depending on @dev.)
++ *
++ * The returned clk (if valid) is prepared and enabled.
++ *
++ * The clock will automatically be disabled, unprepared and freed
++ * when the device is unbound from the bus.
++ */
++struct clk *devm_clk_get_enabled(struct device *dev, const char *id);
++
+ /**
+  * devm_clk_get_optional - lookup and obtain a managed reference to an optional
+  *			   clock producer.
+@@ -469,6 +510,50 @@ struct clk *devm_clk_get(struct device *dev, const char *id);
+  */
+ struct clk *devm_clk_get_optional(struct device *dev, const char *id);
+ 
++/**
++ * devm_clk_get_optional_prepared - devm_clk_get_optional() + clk_prepare()
++ * @dev: device for clock "consumer"
++ * @id: clock consumer ID
++ *
++ * Context: May sleep.
++ *
++ * Return: a struct clk corresponding to the clock producer, or
++ * valid IS_ERR() condition containing errno.  The implementation
++ * uses @dev and @id to determine the clock consumer, and thereby
++ * the clock producer.  If no such clk is found, it returns NULL
++ * which serves as a dummy clk.  That's the only difference compared
++ * to devm_clk_get_prepared().
++ *
++ * The returned clk (if valid) is prepared. Drivers must however
++ * assume that the clock is not enabled.
++ *
++ * The clock will automatically be unprepared and freed when the
++ * device is unbound from the bus.
++ */
++struct clk *devm_clk_get_optional_prepared(struct device *dev, const char *id);
++
++/**
++ * devm_clk_get_optional_enabled - devm_clk_get_optional() +
++ *                                 clk_prepare_enable()
++ * @dev: device for clock "consumer"
++ * @id: clock consumer ID
++ *
++ * Context: May sleep.
++ *
++ * Return: a struct clk corresponding to the clock producer, or
++ * valid IS_ERR() condition containing errno.  The implementation
++ * uses @dev and @id to determine the clock consumer, and thereby
++ * the clock producer.  If no such clk is found, it returns NULL
++ * which serves as a dummy clk.  That's the only difference compared
++ * to devm_clk_get_enabled().
++ *
++ * The returned clk (if valid) is prepared and enabled.
++ *
++ * The clock will automatically be disabled, unprepared and freed
++ * when the device is unbound from the bus.
++ */
++struct clk *devm_clk_get_optional_enabled(struct device *dev, const char *id);
++
+ /**
+  * devm_get_clk_from_child - lookup and obtain a managed reference to a
+  *			     clock producer from child node.
+@@ -813,12 +898,36 @@ static inline struct clk *devm_clk_get(struct device *dev, const char *id)
+ 	return NULL;
+ }
+ 
++static inline struct clk *devm_clk_get_prepared(struct device *dev,
++						const char *id)
++{
++	return NULL;
++}
++
++static inline struct clk *devm_clk_get_enabled(struct device *dev,
++					       const char *id)
++{
++	return NULL;
++}
++
+ static inline struct clk *devm_clk_get_optional(struct device *dev,
+ 						const char *id)
+ {
+ 	return NULL;
+ }
+ 
++static inline struct clk *devm_clk_get_optional_prepared(struct device *dev,
++							 const char *id)
++{
++	return NULL;
++}
++
++static inline struct clk *devm_clk_get_optional_enabled(struct device *dev,
++							const char *id)
++{
++	return NULL;
++}
++
+ static inline int __must_check devm_clk_bulk_get(struct device *dev, int num_clks,
+ 						 struct clk_bulk_data *clks)
+ {
+diff --git a/include/linux/mc146818rtc.h b/include/linux/mc146818rtc.h
+index 3038124c61154..b0da04fe087bb 100644
+--- a/include/linux/mc146818rtc.h
++++ b/include/linux/mc146818rtc.h
+@@ -129,4 +129,7 @@ bool mc146818_does_rtc_work(void);
+ int mc146818_get_time(struct rtc_time *time);
+ int mc146818_set_time(struct rtc_time *time);
+ 
++bool mc146818_avoid_UIP(void (*callback)(unsigned char seconds, void *param),
++			void *param);
++
+ #endif /* _MC146818RTC_H */
+diff --git a/io_uring/Makefile b/io_uring/Makefile
+new file mode 100644
+index 0000000000000..3680425df9478
+--- /dev/null
++++ b/io_uring/Makefile
+@@ -0,0 +1,6 @@
++# SPDX-License-Identifier: GPL-2.0
++#
++# Makefile for io_uring
++
++obj-$(CONFIG_IO_URING)		+= io_uring.o
++obj-$(CONFIG_IO_WQ)		+= io-wq.o
+diff --git a/io_uring/io-wq.c b/io_uring/io-wq.c
+new file mode 100644
+index 0000000000000..6031fb319d878
+--- /dev/null
++++ b/io_uring/io-wq.c
+@@ -0,0 +1,1398 @@
++// SPDX-License-Identifier: GPL-2.0
++/*
++ * Basic worker thread pool for io_uring
++ *
++ * Copyright (C) 2019 Jens Axboe
++ *
++ */
++#include <linux/kernel.h>
++#include <linux/init.h>
++#include <linux/errno.h>
++#include <linux/sched/signal.h>
++#include <linux/percpu.h>
++#include <linux/slab.h>
++#include <linux/rculist_nulls.h>
++#include <linux/cpu.h>
++#include <linux/tracehook.h>
++#include <uapi/linux/io_uring.h>
++
++#include "io-wq.h"
++
++#define WORKER_IDLE_TIMEOUT	(5 * HZ)
++
++enum {
++	IO_WORKER_F_UP		= 1,	/* up and active */
++	IO_WORKER_F_RUNNING	= 2,	/* account as running */
++	IO_WORKER_F_FREE	= 4,	/* worker on free list */
++	IO_WORKER_F_BOUND	= 8,	/* is doing bounded work */
++};
++
++enum {
++	IO_WQ_BIT_EXIT		= 0,	/* wq exiting */
++};
++
++enum {
++	IO_ACCT_STALLED_BIT	= 0,	/* stalled on hash */
++};
++
++/*
++ * One for each thread in a wqe pool
++ */
++struct io_worker {
++	refcount_t ref;
++	unsigned flags;
++	struct hlist_nulls_node nulls_node;
++	struct list_head all_list;
++	struct task_struct *task;
++	struct io_wqe *wqe;
++
++	struct io_wq_work *cur_work;
++	spinlock_t lock;
++
++	struct completion ref_done;
++
++	unsigned long create_state;
++	struct callback_head create_work;
++	int create_index;
++
++	union {
++		struct rcu_head rcu;
++		struct work_struct work;
++	};
++};
++
++#if BITS_PER_LONG == 64
++#define IO_WQ_HASH_ORDER	6
++#else
++#define IO_WQ_HASH_ORDER	5
++#endif
++
++#define IO_WQ_NR_HASH_BUCKETS	(1u << IO_WQ_HASH_ORDER)
++
++struct io_wqe_acct {
++	unsigned nr_workers;
++	unsigned max_workers;
++	int index;
++	atomic_t nr_running;
++	struct io_wq_work_list work_list;
++	unsigned long flags;
++};
++
++enum {
++	IO_WQ_ACCT_BOUND,
++	IO_WQ_ACCT_UNBOUND,
++	IO_WQ_ACCT_NR,
++};
++
++/*
++ * Per-node worker thread pool
++ */
++struct io_wqe {
++	raw_spinlock_t lock;
++	struct io_wqe_acct acct[2];
++
++	int node;
++
++	struct hlist_nulls_head free_list;
++	struct list_head all_list;
++
++	struct wait_queue_entry wait;
++
++	struct io_wq *wq;
++	struct io_wq_work *hash_tail[IO_WQ_NR_HASH_BUCKETS];
++
++	cpumask_var_t cpu_mask;
++};
++
++/*
++ * Per io_wq state
++  */
++struct io_wq {
++	unsigned long state;
++
++	free_work_fn *free_work;
++	io_wq_work_fn *do_work;
++
++	struct io_wq_hash *hash;
++
++	atomic_t worker_refs;
++	struct completion worker_done;
++
++	struct hlist_node cpuhp_node;
++
++	struct task_struct *task;
++
++	struct io_wqe *wqes[];
++};
++
++static enum cpuhp_state io_wq_online;
++
++struct io_cb_cancel_data {
++	work_cancel_fn *fn;
++	void *data;
++	int nr_running;
++	int nr_pending;
++	bool cancel_all;
++};
++
++static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index);
++static void io_wqe_dec_running(struct io_worker *worker);
++static bool io_acct_cancel_pending_work(struct io_wqe *wqe,
++					struct io_wqe_acct *acct,
++					struct io_cb_cancel_data *match);
++static void create_worker_cb(struct callback_head *cb);
++static void io_wq_cancel_tw_create(struct io_wq *wq);
++
++static bool io_worker_get(struct io_worker *worker)
++{
++	return refcount_inc_not_zero(&worker->ref);
++}
++
++static void io_worker_release(struct io_worker *worker)
++{
++	if (refcount_dec_and_test(&worker->ref))
++		complete(&worker->ref_done);
++}
++
++static inline struct io_wqe_acct *io_get_acct(struct io_wqe *wqe, bool bound)
++{
++	return &wqe->acct[bound ? IO_WQ_ACCT_BOUND : IO_WQ_ACCT_UNBOUND];
++}
++
++static inline struct io_wqe_acct *io_work_get_acct(struct io_wqe *wqe,
++						   struct io_wq_work *work)
++{
++	return io_get_acct(wqe, !(work->flags & IO_WQ_WORK_UNBOUND));
++}
++
++static inline struct io_wqe_acct *io_wqe_get_acct(struct io_worker *worker)
++{
++	return io_get_acct(worker->wqe, worker->flags & IO_WORKER_F_BOUND);
++}
++
++static void io_worker_ref_put(struct io_wq *wq)
++{
++	if (atomic_dec_and_test(&wq->worker_refs))
++		complete(&wq->worker_done);
++}
++
++static void io_worker_cancel_cb(struct io_worker *worker)
++{
++	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
++	struct io_wqe *wqe = worker->wqe;
++	struct io_wq *wq = wqe->wq;
++
++	atomic_dec(&acct->nr_running);
++	raw_spin_lock(&worker->wqe->lock);
++	acct->nr_workers--;
++	raw_spin_unlock(&worker->wqe->lock);
++	io_worker_ref_put(wq);
++	clear_bit_unlock(0, &worker->create_state);
++	io_worker_release(worker);
++}
++
++static bool io_task_worker_match(struct callback_head *cb, void *data)
++{
++	struct io_worker *worker;
++
++	if (cb->func != create_worker_cb)
++		return false;
++	worker = container_of(cb, struct io_worker, create_work);
++	return worker == data;
++}
++
++static void io_worker_exit(struct io_worker *worker)
++{
++	struct io_wqe *wqe = worker->wqe;
++	struct io_wq *wq = wqe->wq;
++
++	while (1) {
++		struct callback_head *cb = task_work_cancel_match(wq->task,
++						io_task_worker_match, worker);
++
++		if (!cb)
++			break;
++		io_worker_cancel_cb(worker);
++	}
++
++	if (refcount_dec_and_test(&worker->ref))
++		complete(&worker->ref_done);
++	wait_for_completion(&worker->ref_done);
++
++	raw_spin_lock(&wqe->lock);
++	if (worker->flags & IO_WORKER_F_FREE)
++		hlist_nulls_del_rcu(&worker->nulls_node);
++	list_del_rcu(&worker->all_list);
++	preempt_disable();
++	io_wqe_dec_running(worker);
++	worker->flags = 0;
++	current->flags &= ~PF_IO_WORKER;
++	preempt_enable();
++	raw_spin_unlock(&wqe->lock);
++
++	kfree_rcu(worker, rcu);
++	io_worker_ref_put(wqe->wq);
++	do_exit(0);
++}
++
++static inline bool io_acct_run_queue(struct io_wqe_acct *acct)
++{
++	if (!wq_list_empty(&acct->work_list) &&
++	    !test_bit(IO_ACCT_STALLED_BIT, &acct->flags))
++		return true;
++	return false;
++}
++
++/*
++ * Check head of free list for an available worker. If one isn't available,
++ * caller must create one.
++ */
++static bool io_wqe_activate_free_worker(struct io_wqe *wqe,
++					struct io_wqe_acct *acct)
++	__must_hold(RCU)
++{
++	struct hlist_nulls_node *n;
++	struct io_worker *worker;
++
++	/*
++	 * Iterate free_list and see if we can find an idle worker to
++	 * activate. If a given worker is on the free_list but in the process
++	 * of exiting, keep trying.
++	 */
++	hlist_nulls_for_each_entry_rcu(worker, n, &wqe->free_list, nulls_node) {
++		if (!io_worker_get(worker))
++			continue;
++		if (io_wqe_get_acct(worker) != acct) {
++			io_worker_release(worker);
++			continue;
++		}
++		if (wake_up_process(worker->task)) {
++			io_worker_release(worker);
++			return true;
++		}
++		io_worker_release(worker);
++	}
++
++	return false;
++}
++
++/*
++ * We need a worker. If we find a free one, we're good. If not, and we're
++ * below the max number of workers, create one.
++ */
++static bool io_wqe_create_worker(struct io_wqe *wqe, struct io_wqe_acct *acct)
++{
++	/*
++	 * Most likely an attempt to queue unbounded work on an io_wq that
++	 * wasn't setup with any unbounded workers.
++	 */
++	if (unlikely(!acct->max_workers))
++		pr_warn_once("io-wq is not configured for unbound workers");
++
++	raw_spin_lock(&wqe->lock);
++	if (acct->nr_workers >= acct->max_workers) {
++		raw_spin_unlock(&wqe->lock);
++		return true;
++	}
++	acct->nr_workers++;
++	raw_spin_unlock(&wqe->lock);
++	atomic_inc(&acct->nr_running);
++	atomic_inc(&wqe->wq->worker_refs);
++	return create_io_worker(wqe->wq, wqe, acct->index);
++}
++
++static void io_wqe_inc_running(struct io_worker *worker)
++{
++	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
++
++	atomic_inc(&acct->nr_running);
++}
++
++static void create_worker_cb(struct callback_head *cb)
++{
++	struct io_worker *worker;
++	struct io_wq *wq;
++	struct io_wqe *wqe;
++	struct io_wqe_acct *acct;
++	bool do_create = false;
++
++	worker = container_of(cb, struct io_worker, create_work);
++	wqe = worker->wqe;
++	wq = wqe->wq;
++	acct = &wqe->acct[worker->create_index];
++	raw_spin_lock(&wqe->lock);
++	if (acct->nr_workers < acct->max_workers) {
++		acct->nr_workers++;
++		do_create = true;
++	}
++	raw_spin_unlock(&wqe->lock);
++	if (do_create) {
++		create_io_worker(wq, wqe, worker->create_index);
++	} else {
++		atomic_dec(&acct->nr_running);
++		io_worker_ref_put(wq);
++	}
++	clear_bit_unlock(0, &worker->create_state);
++	io_worker_release(worker);
++}
++
++static bool io_queue_worker_create(struct io_worker *worker,
++				   struct io_wqe_acct *acct,
++				   task_work_func_t func)
++{
++	struct io_wqe *wqe = worker->wqe;
++	struct io_wq *wq = wqe->wq;
++
++	/* raced with exit, just ignore create call */
++	if (test_bit(IO_WQ_BIT_EXIT, &wq->state))
++		goto fail;
++	if (!io_worker_get(worker))
++		goto fail;
++	/*
++	 * create_state manages ownership of create_work/index. We should
++	 * only need one entry per worker, as the worker going to sleep
++	 * will trigger the condition, and waking will clear it once it
++	 * runs the task_work.
++	 */
++	if (test_bit(0, &worker->create_state) ||
++	    test_and_set_bit_lock(0, &worker->create_state))
++		goto fail_release;
++
++	atomic_inc(&wq->worker_refs);
++	init_task_work(&worker->create_work, func);
++	worker->create_index = acct->index;
++	if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL)) {
++		/*
++		 * EXIT may have been set after checking it above, check after
++		 * adding the task_work and remove any creation item if it is
++		 * now set. wq exit does that too, but we can have added this
++		 * work item after we canceled in io_wq_exit_workers().
++		 */
++		if (test_bit(IO_WQ_BIT_EXIT, &wq->state))
++			io_wq_cancel_tw_create(wq);
++		io_worker_ref_put(wq);
++		return true;
++	}
++	io_worker_ref_put(wq);
++	clear_bit_unlock(0, &worker->create_state);
++fail_release:
++	io_worker_release(worker);
++fail:
++	atomic_dec(&acct->nr_running);
++	io_worker_ref_put(wq);
++	return false;
++}
++
++static void io_wqe_dec_running(struct io_worker *worker)
++	__must_hold(wqe->lock)
++{
++	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
++	struct io_wqe *wqe = worker->wqe;
++
++	if (!(worker->flags & IO_WORKER_F_UP))
++		return;
++
++	if (atomic_dec_and_test(&acct->nr_running) && io_acct_run_queue(acct)) {
++		atomic_inc(&acct->nr_running);
++		atomic_inc(&wqe->wq->worker_refs);
++		raw_spin_unlock(&wqe->lock);
++		io_queue_worker_create(worker, acct, create_worker_cb);
++		raw_spin_lock(&wqe->lock);
++	}
++}
++
++/*
++ * Worker will start processing some work. Move it to the busy list, if
++ * it's currently on the freelist
++ */
++static void __io_worker_busy(struct io_wqe *wqe, struct io_worker *worker,
++			     struct io_wq_work *work)
++	__must_hold(wqe->lock)
++{
++	if (worker->flags & IO_WORKER_F_FREE) {
++		worker->flags &= ~IO_WORKER_F_FREE;
++		hlist_nulls_del_init_rcu(&worker->nulls_node);
++	}
++}
++
++/*
++ * No work, worker going to sleep. Move to freelist, and unuse mm if we
++ * have one attached. Dropping the mm may potentially sleep, so we drop
++ * the lock in that case and return success. Since the caller has to
++ * retry the loop in that case (we changed task state), we don't regrab
++ * the lock if we return success.
++ */
++static void __io_worker_idle(struct io_wqe *wqe, struct io_worker *worker)
++	__must_hold(wqe->lock)
++{
++	if (!(worker->flags & IO_WORKER_F_FREE)) {
++		worker->flags |= IO_WORKER_F_FREE;
++		hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list);
++	}
++}
++
++static inline unsigned int io_get_work_hash(struct io_wq_work *work)
++{
++	return work->flags >> IO_WQ_HASH_SHIFT;
++}
++
++static bool io_wait_on_hash(struct io_wqe *wqe, unsigned int hash)
++{
++	struct io_wq *wq = wqe->wq;
++	bool ret = false;
++
++	spin_lock_irq(&wq->hash->wait.lock);
++	if (list_empty(&wqe->wait.entry)) {
++		__add_wait_queue(&wq->hash->wait, &wqe->wait);
++		if (!test_bit(hash, &wq->hash->map)) {
++			__set_current_state(TASK_RUNNING);
++			list_del_init(&wqe->wait.entry);
++			ret = true;
++		}
++	}
++	spin_unlock_irq(&wq->hash->wait.lock);
++	return ret;
++}
++
++static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct,
++					   struct io_worker *worker)
++	__must_hold(wqe->lock)
++{
++	struct io_wq_work_node *node, *prev;
++	struct io_wq_work *work, *tail;
++	unsigned int stall_hash = -1U;
++	struct io_wqe *wqe = worker->wqe;
++
++	wq_list_for_each(node, prev, &acct->work_list) {
++		unsigned int hash;
++
++		work = container_of(node, struct io_wq_work, list);
++
++		/* not hashed, can run anytime */
++		if (!io_wq_is_hashed(work)) {
++			wq_list_del(&acct->work_list, node, prev);
++			return work;
++		}
++
++		hash = io_get_work_hash(work);
++		/* all items with this hash lie in [work, tail] */
++		tail = wqe->hash_tail[hash];
++
++		/* hashed, can run if not already running */
++		if (!test_and_set_bit(hash, &wqe->wq->hash->map)) {
++			wqe->hash_tail[hash] = NULL;
++			wq_list_cut(&acct->work_list, &tail->list, prev);
++			return work;
++		}
++		if (stall_hash == -1U)
++			stall_hash = hash;
++		/* fast forward to a next hash, for-each will fix up @prev */
++		node = &tail->list;
++	}
++
++	if (stall_hash != -1U) {
++		bool unstalled;
++
++		/*
++		 * Set this before dropping the lock to avoid racing with new
++		 * work being added and clearing the stalled bit.
++		 */
++		set_bit(IO_ACCT_STALLED_BIT, &acct->flags);
++		raw_spin_unlock(&wqe->lock);
++		unstalled = io_wait_on_hash(wqe, stall_hash);
++		raw_spin_lock(&wqe->lock);
++		if (unstalled) {
++			clear_bit(IO_ACCT_STALLED_BIT, &acct->flags);
++			if (wq_has_sleeper(&wqe->wq->hash->wait))
++				wake_up(&wqe->wq->hash->wait);
++		}
++	}
++
++	return NULL;
++}
++
++static bool io_flush_signals(void)
++{
++	if (unlikely(test_thread_flag(TIF_NOTIFY_SIGNAL))) {
++		__set_current_state(TASK_RUNNING);
++		tracehook_notify_signal();
++		return true;
++	}
++	return false;
++}
++
++static void io_assign_current_work(struct io_worker *worker,
++				   struct io_wq_work *work)
++{
++	if (work) {
++		io_flush_signals();
++		cond_resched();
++	}
++
++	spin_lock(&worker->lock);
++	worker->cur_work = work;
++	spin_unlock(&worker->lock);
++}
++
++static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work);
++
++static void io_worker_handle_work(struct io_worker *worker)
++	__releases(wqe->lock)
++{
++	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
++	struct io_wqe *wqe = worker->wqe;
++	struct io_wq *wq = wqe->wq;
++	bool do_kill = test_bit(IO_WQ_BIT_EXIT, &wq->state);
++
++	do {
++		struct io_wq_work *work;
++get_next:
++		/*
++		 * If we got some work, mark us as busy. If we didn't, but
++		 * the list isn't empty, it means we stalled on hashed work.
++		 * Mark us stalled so we don't keep looking for work when we
++		 * can't make progress, any work completion or insertion will
++		 * clear the stalled flag.
++		 */
++		work = io_get_next_work(acct, worker);
++		if (work)
++			__io_worker_busy(wqe, worker, work);
++
++		raw_spin_unlock(&wqe->lock);
++		if (!work)
++			break;
++		io_assign_current_work(worker, work);
++		__set_current_state(TASK_RUNNING);
++
++		/* handle a whole dependent link */
++		do {
++			struct io_wq_work *next_hashed, *linked;
++			unsigned int hash = io_get_work_hash(work);
++
++			next_hashed = wq_next_work(work);
++
++			if (unlikely(do_kill) && (work->flags & IO_WQ_WORK_UNBOUND))
++				work->flags |= IO_WQ_WORK_CANCEL;
++			wq->do_work(work);
++			io_assign_current_work(worker, NULL);
++
++			linked = wq->free_work(work);
++			work = next_hashed;
++			if (!work && linked && !io_wq_is_hashed(linked)) {
++				work = linked;
++				linked = NULL;
++			}
++			io_assign_current_work(worker, work);
++			if (linked)
++				io_wqe_enqueue(wqe, linked);
++
++			if (hash != -1U && !next_hashed) {
++				/* serialize hash clear with wake_up() */
++				spin_lock_irq(&wq->hash->wait.lock);
++				clear_bit(hash, &wq->hash->map);
++				clear_bit(IO_ACCT_STALLED_BIT, &acct->flags);
++				spin_unlock_irq(&wq->hash->wait.lock);
++				if (wq_has_sleeper(&wq->hash->wait))
++					wake_up(&wq->hash->wait);
++				raw_spin_lock(&wqe->lock);
++				/* skip unnecessary unlock-lock wqe->lock */
++				if (!work)
++					goto get_next;
++				raw_spin_unlock(&wqe->lock);
++			}
++		} while (work);
++
++		raw_spin_lock(&wqe->lock);
++	} while (1);
++}
++
++static int io_wqe_worker(void *data)
++{
++	struct io_worker *worker = data;
++	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
++	struct io_wqe *wqe = worker->wqe;
++	struct io_wq *wq = wqe->wq;
++	bool last_timeout = false;
++	char buf[TASK_COMM_LEN];
++
++	worker->flags |= (IO_WORKER_F_UP | IO_WORKER_F_RUNNING);
++
++	snprintf(buf, sizeof(buf), "iou-wrk-%d", wq->task->pid);
++	set_task_comm(current, buf);
++
++	while (!test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
++		long ret;
++
++		set_current_state(TASK_INTERRUPTIBLE);
++loop:
++		raw_spin_lock(&wqe->lock);
++		if (io_acct_run_queue(acct)) {
++			io_worker_handle_work(worker);
++			goto loop;
++		}
++		/* timed out, exit unless we're the last worker */
++		if (last_timeout && acct->nr_workers > 1) {
++			acct->nr_workers--;
++			raw_spin_unlock(&wqe->lock);
++			__set_current_state(TASK_RUNNING);
++			break;
++		}
++		last_timeout = false;
++		__io_worker_idle(wqe, worker);
++		raw_spin_unlock(&wqe->lock);
++		if (io_flush_signals())
++			continue;
++		ret = schedule_timeout(WORKER_IDLE_TIMEOUT);
++		if (signal_pending(current)) {
++			struct ksignal ksig;
++
++			if (!get_signal(&ksig))
++				continue;
++			break;
++		}
++		last_timeout = !ret;
++	}
++
++	if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) {
++		raw_spin_lock(&wqe->lock);
++		io_worker_handle_work(worker);
++	}
++
++	io_worker_exit(worker);
++	return 0;
++}
++
++/*
++ * Called when a worker is scheduled in. Mark us as currently running.
++ */
++void io_wq_worker_running(struct task_struct *tsk)
++{
++	struct io_worker *worker = tsk->pf_io_worker;
++
++	if (!worker)
++		return;
++	if (!(worker->flags & IO_WORKER_F_UP))
++		return;
++	if (worker->flags & IO_WORKER_F_RUNNING)
++		return;
++	worker->flags |= IO_WORKER_F_RUNNING;
++	io_wqe_inc_running(worker);
++}
++
++/*
++ * Called when worker is going to sleep. If there are no workers currently
++ * running and we have work pending, wake up a free one or create a new one.
++ */
++void io_wq_worker_sleeping(struct task_struct *tsk)
++{
++	struct io_worker *worker = tsk->pf_io_worker;
++
++	if (!worker)
++		return;
++	if (!(worker->flags & IO_WORKER_F_UP))
++		return;
++	if (!(worker->flags & IO_WORKER_F_RUNNING))
++		return;
++
++	worker->flags &= ~IO_WORKER_F_RUNNING;
++
++	raw_spin_lock(&worker->wqe->lock);
++	io_wqe_dec_running(worker);
++	raw_spin_unlock(&worker->wqe->lock);
++}
++
++static void io_init_new_worker(struct io_wqe *wqe, struct io_worker *worker,
++			       struct task_struct *tsk)
++{
++	tsk->pf_io_worker = worker;
++	worker->task = tsk;
++	set_cpus_allowed_ptr(tsk, wqe->cpu_mask);
++	tsk->flags |= PF_NO_SETAFFINITY;
++
++	raw_spin_lock(&wqe->lock);
++	hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list);
++	list_add_tail_rcu(&worker->all_list, &wqe->all_list);
++	worker->flags |= IO_WORKER_F_FREE;
++	raw_spin_unlock(&wqe->lock);
++	wake_up_new_task(tsk);
++}
++
++static bool io_wq_work_match_all(struct io_wq_work *work, void *data)
++{
++	return true;
++}
++
++static inline bool io_should_retry_thread(long err)
++{
++	/*
++	 * Prevent perpetual task_work retry, if the task (or its group) is
++	 * exiting.
++	 */
++	if (fatal_signal_pending(current))
++		return false;
++
++	switch (err) {
++	case -EAGAIN:
++	case -ERESTARTSYS:
++	case -ERESTARTNOINTR:
++	case -ERESTARTNOHAND:
++		return true;
++	default:
++		return false;
++	}
++}
++
++static void create_worker_cont(struct callback_head *cb)
++{
++	struct io_worker *worker;
++	struct task_struct *tsk;
++	struct io_wqe *wqe;
++
++	worker = container_of(cb, struct io_worker, create_work);
++	clear_bit_unlock(0, &worker->create_state);
++	wqe = worker->wqe;
++	tsk = create_io_thread(io_wqe_worker, worker, wqe->node);
++	if (!IS_ERR(tsk)) {
++		io_init_new_worker(wqe, worker, tsk);
++		io_worker_release(worker);
++		return;
++	} else if (!io_should_retry_thread(PTR_ERR(tsk))) {
++		struct io_wqe_acct *acct = io_wqe_get_acct(worker);
++
++		atomic_dec(&acct->nr_running);
++		raw_spin_lock(&wqe->lock);
++		acct->nr_workers--;
++		if (!acct->nr_workers) {
++			struct io_cb_cancel_data match = {
++				.fn		= io_wq_work_match_all,
++				.cancel_all	= true,
++			};
++
++			while (io_acct_cancel_pending_work(wqe, acct, &match))
++				raw_spin_lock(&wqe->lock);
++		}
++		raw_spin_unlock(&wqe->lock);
++		io_worker_ref_put(wqe->wq);
++		kfree(worker);
++		return;
++	}
++
++	/* re-create attempts grab a new worker ref, drop the existing one */
++	io_worker_release(worker);
++	schedule_work(&worker->work);
++}
++
++static void io_workqueue_create(struct work_struct *work)
++{
++	struct io_worker *worker = container_of(work, struct io_worker, work);
++	struct io_wqe_acct *acct = io_wqe_get_acct(worker);
++
++	if (!io_queue_worker_create(worker, acct, create_worker_cont))
++		kfree(worker);
++}
++
++static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index)
++{
++	struct io_wqe_acct *acct = &wqe->acct[index];
++	struct io_worker *worker;
++	struct task_struct *tsk;
++
++	__set_current_state(TASK_RUNNING);
++
++	worker = kzalloc_node(sizeof(*worker), GFP_KERNEL, wqe->node);
++	if (!worker) {
++fail:
++		atomic_dec(&acct->nr_running);
++		raw_spin_lock(&wqe->lock);
++		acct->nr_workers--;
++		raw_spin_unlock(&wqe->lock);
++		io_worker_ref_put(wq);
++		return false;
++	}
++
++	refcount_set(&worker->ref, 1);
++	worker->wqe = wqe;
++	spin_lock_init(&worker->lock);
++	init_completion(&worker->ref_done);
++
++	if (index == IO_WQ_ACCT_BOUND)
++		worker->flags |= IO_WORKER_F_BOUND;
++
++	tsk = create_io_thread(io_wqe_worker, worker, wqe->node);
++	if (!IS_ERR(tsk)) {
++		io_init_new_worker(wqe, worker, tsk);
++	} else if (!io_should_retry_thread(PTR_ERR(tsk))) {
++		kfree(worker);
++		goto fail;
++	} else {
++		INIT_WORK(&worker->work, io_workqueue_create);
++		schedule_work(&worker->work);
++	}
++
++	return true;
++}
++
++/*
++ * Iterate the passed in list and call the specific function for each
++ * worker that isn't exiting
++ */
++static bool io_wq_for_each_worker(struct io_wqe *wqe,
++				  bool (*func)(struct io_worker *, void *),
++				  void *data)
++{
++	struct io_worker *worker;
++	bool ret = false;
++
++	list_for_each_entry_rcu(worker, &wqe->all_list, all_list) {
++		if (io_worker_get(worker)) {
++			/* no task if node is/was offline */
++			if (worker->task)
++				ret = func(worker, data);
++			io_worker_release(worker);
++			if (ret)
++				break;
++		}
++	}
++
++	return ret;
++}
++
++static bool io_wq_worker_wake(struct io_worker *worker, void *data)
++{
++	set_notify_signal(worker->task);
++	wake_up_process(worker->task);
++	return false;
++}
++
++static void io_run_cancel(struct io_wq_work *work, struct io_wqe *wqe)
++{
++	struct io_wq *wq = wqe->wq;
++
++	do {
++		work->flags |= IO_WQ_WORK_CANCEL;
++		wq->do_work(work);
++		work = wq->free_work(work);
++	} while (work);
++}
++
++static void io_wqe_insert_work(struct io_wqe *wqe, struct io_wq_work *work)
++{
++	struct io_wqe_acct *acct = io_work_get_acct(wqe, work);
++	unsigned int hash;
++	struct io_wq_work *tail;
++
++	if (!io_wq_is_hashed(work)) {
++append:
++		wq_list_add_tail(&work->list, &acct->work_list);
++		return;
++	}
++
++	hash = io_get_work_hash(work);
++	tail = wqe->hash_tail[hash];
++	wqe->hash_tail[hash] = work;
++	if (!tail)
++		goto append;
++
++	wq_list_add_after(&work->list, &tail->list, &acct->work_list);
++}
++
++static bool io_wq_work_match_item(struct io_wq_work *work, void *data)
++{
++	return work == data;
++}
++
++static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work)
++{
++	struct io_wqe_acct *acct = io_work_get_acct(wqe, work);
++	unsigned work_flags = work->flags;
++	bool do_create;
++
++	/*
++	 * If io-wq is exiting for this task, or if the request has explicitly
++	 * been marked as one that should not get executed, cancel it here.
++	 */
++	if (test_bit(IO_WQ_BIT_EXIT, &wqe->wq->state) ||
++	    (work->flags & IO_WQ_WORK_CANCEL)) {
++		io_run_cancel(work, wqe);
++		return;
++	}
++
++	raw_spin_lock(&wqe->lock);
++	io_wqe_insert_work(wqe, work);
++	clear_bit(IO_ACCT_STALLED_BIT, &acct->flags);
++
++	rcu_read_lock();
++	do_create = !io_wqe_activate_free_worker(wqe, acct);
++	rcu_read_unlock();
++
++	raw_spin_unlock(&wqe->lock);
++
++	if (do_create && ((work_flags & IO_WQ_WORK_CONCURRENT) ||
++	    !atomic_read(&acct->nr_running))) {
++		bool did_create;
++
++		did_create = io_wqe_create_worker(wqe, acct);
++		if (likely(did_create))
++			return;
++
++		raw_spin_lock(&wqe->lock);
++		/* fatal condition, failed to create the first worker */
++		if (!acct->nr_workers) {
++			struct io_cb_cancel_data match = {
++				.fn		= io_wq_work_match_item,
++				.data		= work,
++				.cancel_all	= false,
++			};
++
++			if (io_acct_cancel_pending_work(wqe, acct, &match))
++				raw_spin_lock(&wqe->lock);
++		}
++		raw_spin_unlock(&wqe->lock);
++	}
++}
++
++void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work)
++{
++	struct io_wqe *wqe = wq->wqes[numa_node_id()];
++
++	io_wqe_enqueue(wqe, work);
++}
++
++/*
++ * Work items that hash to the same value will not be done in parallel.
++ * Used to limit concurrent writes, generally hashed by inode.
++ */
++void io_wq_hash_work(struct io_wq_work *work, void *val)
++{
++	unsigned int bit;
++
++	bit = hash_ptr(val, IO_WQ_HASH_ORDER);
++	work->flags |= (IO_WQ_WORK_HASHED | (bit << IO_WQ_HASH_SHIFT));
++}
++
++static bool io_wq_worker_cancel(struct io_worker *worker, void *data)
++{
++	struct io_cb_cancel_data *match = data;
++
++	/*
++	 * Hold the lock to avoid ->cur_work going out of scope, caller
++	 * may dereference the passed in work.
++	 */
++	spin_lock(&worker->lock);
++	if (worker->cur_work &&
++	    match->fn(worker->cur_work, match->data)) {
++		set_notify_signal(worker->task);
++		match->nr_running++;
++	}
++	spin_unlock(&worker->lock);
++
++	return match->nr_running && !match->cancel_all;
++}
++
++static inline void io_wqe_remove_pending(struct io_wqe *wqe,
++					 struct io_wq_work *work,
++					 struct io_wq_work_node *prev)
++{
++	struct io_wqe_acct *acct = io_work_get_acct(wqe, work);
++	unsigned int hash = io_get_work_hash(work);
++	struct io_wq_work *prev_work = NULL;
++
++	if (io_wq_is_hashed(work) && work == wqe->hash_tail[hash]) {
++		if (prev)
++			prev_work = container_of(prev, struct io_wq_work, list);
++		if (prev_work && io_get_work_hash(prev_work) == hash)
++			wqe->hash_tail[hash] = prev_work;
++		else
++			wqe->hash_tail[hash] = NULL;
++	}
++	wq_list_del(&acct->work_list, &work->list, prev);
++}
++
++static bool io_acct_cancel_pending_work(struct io_wqe *wqe,
++					struct io_wqe_acct *acct,
++					struct io_cb_cancel_data *match)
++	__releases(wqe->lock)
++{
++	struct io_wq_work_node *node, *prev;
++	struct io_wq_work *work;
++
++	wq_list_for_each(node, prev, &acct->work_list) {
++		work = container_of(node, struct io_wq_work, list);
++		if (!match->fn(work, match->data))
++			continue;
++		io_wqe_remove_pending(wqe, work, prev);
++		raw_spin_unlock(&wqe->lock);
++		io_run_cancel(work, wqe);
++		match->nr_pending++;
++		/* not safe to continue after unlock */
++		return true;
++	}
++
++	return false;
++}
++
++static void io_wqe_cancel_pending_work(struct io_wqe *wqe,
++				       struct io_cb_cancel_data *match)
++{
++	int i;
++retry:
++	raw_spin_lock(&wqe->lock);
++	for (i = 0; i < IO_WQ_ACCT_NR; i++) {
++		struct io_wqe_acct *acct = io_get_acct(wqe, i == 0);
++
++		if (io_acct_cancel_pending_work(wqe, acct, match)) {
++			if (match->cancel_all)
++				goto retry;
++			return;
++		}
++	}
++	raw_spin_unlock(&wqe->lock);
++}
++
++static void io_wqe_cancel_running_work(struct io_wqe *wqe,
++				       struct io_cb_cancel_data *match)
++{
++	rcu_read_lock();
++	io_wq_for_each_worker(wqe, io_wq_worker_cancel, match);
++	rcu_read_unlock();
++}
++
++enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
++				  void *data, bool cancel_all)
++{
++	struct io_cb_cancel_data match = {
++		.fn		= cancel,
++		.data		= data,
++		.cancel_all	= cancel_all,
++	};
++	int node;
++
++	/*
++	 * First check pending list, if we're lucky we can just remove it
++	 * from there. CANCEL_OK means that the work is returned as-new,
++	 * no completion will be posted for it.
++	 */
++	for_each_node(node) {
++		struct io_wqe *wqe = wq->wqes[node];
++
++		io_wqe_cancel_pending_work(wqe, &match);
++		if (match.nr_pending && !match.cancel_all)
++			return IO_WQ_CANCEL_OK;
++	}
++
++	/*
++	 * Now check if a free (going busy) or busy worker has the work
++	 * currently running. If we find it there, we'll return CANCEL_RUNNING
++	 * as an indication that we attempt to signal cancellation. The
++	 * completion will run normally in this case.
++	 */
++	for_each_node(node) {
++		struct io_wqe *wqe = wq->wqes[node];
++
++		io_wqe_cancel_running_work(wqe, &match);
++		if (match.nr_running && !match.cancel_all)
++			return IO_WQ_CANCEL_RUNNING;
++	}
++
++	if (match.nr_running)
++		return IO_WQ_CANCEL_RUNNING;
++	if (match.nr_pending)
++		return IO_WQ_CANCEL_OK;
++	return IO_WQ_CANCEL_NOTFOUND;
++}
++
++static int io_wqe_hash_wake(struct wait_queue_entry *wait, unsigned mode,
++			    int sync, void *key)
++{
++	struct io_wqe *wqe = container_of(wait, struct io_wqe, wait);
++	int i;
++
++	list_del_init(&wait->entry);
++
++	rcu_read_lock();
++	for (i = 0; i < IO_WQ_ACCT_NR; i++) {
++		struct io_wqe_acct *acct = &wqe->acct[i];
++
++		if (test_and_clear_bit(IO_ACCT_STALLED_BIT, &acct->flags))
++			io_wqe_activate_free_worker(wqe, acct);
++	}
++	rcu_read_unlock();
++	return 1;
++}
++
++struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data)
++{
++	int ret, node, i;
++	struct io_wq *wq;
++
++	if (WARN_ON_ONCE(!data->free_work || !data->do_work))
++		return ERR_PTR(-EINVAL);
++	if (WARN_ON_ONCE(!bounded))
++		return ERR_PTR(-EINVAL);
++
++	wq = kzalloc(struct_size(wq, wqes, nr_node_ids), GFP_KERNEL);
++	if (!wq)
++		return ERR_PTR(-ENOMEM);
++	ret = cpuhp_state_add_instance_nocalls(io_wq_online, &wq->cpuhp_node);
++	if (ret)
++		goto err_wq;
++
++	refcount_inc(&data->hash->refs);
++	wq->hash = data->hash;
++	wq->free_work = data->free_work;
++	wq->do_work = data->do_work;
++
++	ret = -ENOMEM;
++	for_each_node(node) {
++		struct io_wqe *wqe;
++		int alloc_node = node;
++
++		if (!node_online(alloc_node))
++			alloc_node = NUMA_NO_NODE;
++		wqe = kzalloc_node(sizeof(struct io_wqe), GFP_KERNEL, alloc_node);
++		if (!wqe)
++			goto err;
++		wq->wqes[node] = wqe;
++		if (!alloc_cpumask_var(&wqe->cpu_mask, GFP_KERNEL))
++			goto err;
++		cpumask_copy(wqe->cpu_mask, cpumask_of_node(node));
++		wqe->node = alloc_node;
++		wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded;
++		wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers =
++					task_rlimit(current, RLIMIT_NPROC);
++		INIT_LIST_HEAD(&wqe->wait.entry);
++		wqe->wait.func = io_wqe_hash_wake;
++		for (i = 0; i < IO_WQ_ACCT_NR; i++) {
++			struct io_wqe_acct *acct = &wqe->acct[i];
++
++			acct->index = i;
++			atomic_set(&acct->nr_running, 0);
++			INIT_WQ_LIST(&acct->work_list);
++		}
++		wqe->wq = wq;
++		raw_spin_lock_init(&wqe->lock);
++		INIT_HLIST_NULLS_HEAD(&wqe->free_list, 0);
++		INIT_LIST_HEAD(&wqe->all_list);
++	}
++
++	wq->task = get_task_struct(data->task);
++	atomic_set(&wq->worker_refs, 1);
++	init_completion(&wq->worker_done);
++	return wq;
++err:
++	io_wq_put_hash(data->hash);
++	cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node);
++	for_each_node(node) {
++		if (!wq->wqes[node])
++			continue;
++		free_cpumask_var(wq->wqes[node]->cpu_mask);
++		kfree(wq->wqes[node]);
++	}
++err_wq:
++	kfree(wq);
++	return ERR_PTR(ret);
++}
++
++static bool io_task_work_match(struct callback_head *cb, void *data)
++{
++	struct io_worker *worker;
++
++	if (cb->func != create_worker_cb && cb->func != create_worker_cont)
++		return false;
++	worker = container_of(cb, struct io_worker, create_work);
++	return worker->wqe->wq == data;
++}
++
++void io_wq_exit_start(struct io_wq *wq)
++{
++	set_bit(IO_WQ_BIT_EXIT, &wq->state);
++}
++
++static void io_wq_cancel_tw_create(struct io_wq *wq)
++{
++	struct callback_head *cb;
++
++	while ((cb = task_work_cancel_match(wq->task, io_task_work_match, wq)) != NULL) {
++		struct io_worker *worker;
++
++		worker = container_of(cb, struct io_worker, create_work);
++		io_worker_cancel_cb(worker);
++	}
++}
++
++static void io_wq_exit_workers(struct io_wq *wq)
++{
++	int node;
++
++	if (!wq->task)
++		return;
++
++	io_wq_cancel_tw_create(wq);
++
++	rcu_read_lock();
++	for_each_node(node) {
++		struct io_wqe *wqe = wq->wqes[node];
++
++		io_wq_for_each_worker(wqe, io_wq_worker_wake, NULL);
++	}
++	rcu_read_unlock();
++	io_worker_ref_put(wq);
++	wait_for_completion(&wq->worker_done);
++
++	for_each_node(node) {
++		spin_lock_irq(&wq->hash->wait.lock);
++		list_del_init(&wq->wqes[node]->wait.entry);
++		spin_unlock_irq(&wq->hash->wait.lock);
++	}
++	put_task_struct(wq->task);
++	wq->task = NULL;
++}
++
++static void io_wq_destroy(struct io_wq *wq)
++{
++	int node;
++
++	cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node);
++
++	for_each_node(node) {
++		struct io_wqe *wqe = wq->wqes[node];
++		struct io_cb_cancel_data match = {
++			.fn		= io_wq_work_match_all,
++			.cancel_all	= true,
++		};
++		io_wqe_cancel_pending_work(wqe, &match);
++		free_cpumask_var(wqe->cpu_mask);
++		kfree(wqe);
++	}
++	io_wq_put_hash(wq->hash);
++	kfree(wq);
++}
++
++void io_wq_put_and_exit(struct io_wq *wq)
++{
++	WARN_ON_ONCE(!test_bit(IO_WQ_BIT_EXIT, &wq->state));
++
++	io_wq_exit_workers(wq);
++	io_wq_destroy(wq);
++}
++
++struct online_data {
++	unsigned int cpu;
++	bool online;
++};
++
++static bool io_wq_worker_affinity(struct io_worker *worker, void *data)
++{
++	struct online_data *od = data;
++
++	if (od->online)
++		cpumask_set_cpu(od->cpu, worker->wqe->cpu_mask);
++	else
++		cpumask_clear_cpu(od->cpu, worker->wqe->cpu_mask);
++	return false;
++}
++
++static int __io_wq_cpu_online(struct io_wq *wq, unsigned int cpu, bool online)
++{
++	struct online_data od = {
++		.cpu = cpu,
++		.online = online
++	};
++	int i;
++
++	rcu_read_lock();
++	for_each_node(i)
++		io_wq_for_each_worker(wq->wqes[i], io_wq_worker_affinity, &od);
++	rcu_read_unlock();
++	return 0;
++}
++
++static int io_wq_cpu_online(unsigned int cpu, struct hlist_node *node)
++{
++	struct io_wq *wq = hlist_entry_safe(node, struct io_wq, cpuhp_node);
++
++	return __io_wq_cpu_online(wq, cpu, true);
++}
++
++static int io_wq_cpu_offline(unsigned int cpu, struct hlist_node *node)
++{
++	struct io_wq *wq = hlist_entry_safe(node, struct io_wq, cpuhp_node);
++
++	return __io_wq_cpu_online(wq, cpu, false);
++}
++
++int io_wq_cpu_affinity(struct io_wq *wq, cpumask_var_t mask)
++{
++	int i;
++
++	rcu_read_lock();
++	for_each_node(i) {
++		struct io_wqe *wqe = wq->wqes[i];
++
++		if (mask)
++			cpumask_copy(wqe->cpu_mask, mask);
++		else
++			cpumask_copy(wqe->cpu_mask, cpumask_of_node(i));
++	}
++	rcu_read_unlock();
++	return 0;
++}
++
++/*
++ * Set max number of unbounded workers, returns old value. If new_count is 0,
++ * then just return the old value.
++ */
++int io_wq_max_workers(struct io_wq *wq, int *new_count)
++{
++	int prev[IO_WQ_ACCT_NR];
++	bool first_node = true;
++	int i, node;
++
++	BUILD_BUG_ON((int) IO_WQ_ACCT_BOUND   != (int) IO_WQ_BOUND);
++	BUILD_BUG_ON((int) IO_WQ_ACCT_UNBOUND != (int) IO_WQ_UNBOUND);
++	BUILD_BUG_ON((int) IO_WQ_ACCT_NR      != 2);
++
++	for (i = 0; i < 2; i++) {
++		if (new_count[i] > task_rlimit(current, RLIMIT_NPROC))
++			new_count[i] = task_rlimit(current, RLIMIT_NPROC);
++	}
++
++	for (i = 0; i < IO_WQ_ACCT_NR; i++)
++		prev[i] = 0;
++
++	rcu_read_lock();
++	for_each_node(node) {
++		struct io_wqe *wqe = wq->wqes[node];
++		struct io_wqe_acct *acct;
++
++		raw_spin_lock(&wqe->lock);
++		for (i = 0; i < IO_WQ_ACCT_NR; i++) {
++			acct = &wqe->acct[i];
++			if (first_node)
++				prev[i] = max_t(int, acct->max_workers, prev[i]);
++			if (new_count[i])
++				acct->max_workers = new_count[i];
++		}
++		raw_spin_unlock(&wqe->lock);
++		first_node = false;
++	}
++	rcu_read_unlock();
++
++	for (i = 0; i < IO_WQ_ACCT_NR; i++)
++		new_count[i] = prev[i];
++
++	return 0;
++}
++
++static __init int io_wq_init(void)
++{
++	int ret;
++
++	ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "io-wq/online",
++					io_wq_cpu_online, io_wq_cpu_offline);
++	if (ret < 0)
++		return ret;
++	io_wq_online = ret;
++	return 0;
++}
++subsys_initcall(io_wq_init);
+diff --git a/io_uring/io-wq.h b/io_uring/io-wq.h
+new file mode 100644
+index 0000000000000..bf5c4c5337605
+--- /dev/null
++++ b/io_uring/io-wq.h
+@@ -0,0 +1,160 @@
++#ifndef INTERNAL_IO_WQ_H
++#define INTERNAL_IO_WQ_H
++
++#include <linux/refcount.h>
++
++struct io_wq;
++
++enum {
++	IO_WQ_WORK_CANCEL	= 1,
++	IO_WQ_WORK_HASHED	= 2,
++	IO_WQ_WORK_UNBOUND	= 4,
++	IO_WQ_WORK_CONCURRENT	= 16,
++
++	IO_WQ_HASH_SHIFT	= 24,	/* upper 8 bits are used for hash key */
++};
++
++enum io_wq_cancel {
++	IO_WQ_CANCEL_OK,	/* cancelled before started */
++	IO_WQ_CANCEL_RUNNING,	/* found, running, and attempted cancelled */
++	IO_WQ_CANCEL_NOTFOUND,	/* work not found */
++};
++
++struct io_wq_work_node {
++	struct io_wq_work_node *next;
++};
++
++struct io_wq_work_list {
++	struct io_wq_work_node *first;
++	struct io_wq_work_node *last;
++};
++
++static inline void wq_list_add_after(struct io_wq_work_node *node,
++				     struct io_wq_work_node *pos,
++				     struct io_wq_work_list *list)
++{
++	struct io_wq_work_node *next = pos->next;
++
++	pos->next = node;
++	node->next = next;
++	if (!next)
++		list->last = node;
++}
++
++static inline void wq_list_add_tail(struct io_wq_work_node *node,
++				    struct io_wq_work_list *list)
++{
++	node->next = NULL;
++	if (!list->first) {
++		list->last = node;
++		WRITE_ONCE(list->first, node);
++	} else {
++		list->last->next = node;
++		list->last = node;
++	}
++}
++
++static inline void wq_list_cut(struct io_wq_work_list *list,
++			       struct io_wq_work_node *last,
++			       struct io_wq_work_node *prev)
++{
++	/* first in the list, if prev==NULL */
++	if (!prev)
++		WRITE_ONCE(list->first, last->next);
++	else
++		prev->next = last->next;
++
++	if (last == list->last)
++		list->last = prev;
++	last->next = NULL;
++}
++
++static inline void wq_list_del(struct io_wq_work_list *list,
++			       struct io_wq_work_node *node,
++			       struct io_wq_work_node *prev)
++{
++	wq_list_cut(list, node, prev);
++}
++
++#define wq_list_for_each(pos, prv, head)			\
++	for (pos = (head)->first, prv = NULL; pos; prv = pos, pos = (pos)->next)
++
++#define wq_list_empty(list)	(READ_ONCE((list)->first) == NULL)
++#define INIT_WQ_LIST(list)	do {				\
++	(list)->first = NULL;					\
++	(list)->last = NULL;					\
++} while (0)
++
++struct io_wq_work {
++	struct io_wq_work_node list;
++	unsigned flags;
++};
++
++static inline struct io_wq_work *wq_next_work(struct io_wq_work *work)
++{
++	if (!work->list.next)
++		return NULL;
++
++	return container_of(work->list.next, struct io_wq_work, list);
++}
++
++typedef struct io_wq_work *(free_work_fn)(struct io_wq_work *);
++typedef void (io_wq_work_fn)(struct io_wq_work *);
++
++struct io_wq_hash {
++	refcount_t refs;
++	unsigned long map;
++	struct wait_queue_head wait;
++};
++
++static inline void io_wq_put_hash(struct io_wq_hash *hash)
++{
++	if (refcount_dec_and_test(&hash->refs))
++		kfree(hash);
++}
++
++struct io_wq_data {
++	struct io_wq_hash *hash;
++	struct task_struct *task;
++	io_wq_work_fn *do_work;
++	free_work_fn *free_work;
++};
++
++struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data);
++void io_wq_exit_start(struct io_wq *wq);
++void io_wq_put_and_exit(struct io_wq *wq);
++
++void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work);
++void io_wq_hash_work(struct io_wq_work *work, void *val);
++
++int io_wq_cpu_affinity(struct io_wq *wq, cpumask_var_t mask);
++int io_wq_max_workers(struct io_wq *wq, int *new_count);
++
++static inline bool io_wq_is_hashed(struct io_wq_work *work)
++{
++	return work->flags & IO_WQ_WORK_HASHED;
++}
++
++typedef bool (work_cancel_fn)(struct io_wq_work *, void *);
++
++enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel,
++					void *data, bool cancel_all);
++
++#if defined(CONFIG_IO_WQ)
++extern void io_wq_worker_sleeping(struct task_struct *);
++extern void io_wq_worker_running(struct task_struct *);
++#else
++static inline void io_wq_worker_sleeping(struct task_struct *tsk)
++{
++}
++static inline void io_wq_worker_running(struct task_struct *tsk)
++{
++}
++#endif
++
++static inline bool io_wq_current_is_worker(void)
++{
++	return in_task() && (current->flags & PF_IO_WORKER) &&
++		current->pf_io_worker;
++}
++#endif
+diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
+new file mode 100644
+index 0000000000000..eebbe8a6da0c5
+--- /dev/null
++++ b/io_uring/io_uring.c
+@@ -0,0 +1,11112 @@
++// SPDX-License-Identifier: GPL-2.0
++/*
++ * Shared application/kernel submission and completion ring pairs, for
++ * supporting fast/efficient IO.
++ *
++ * A note on the read/write ordering memory barriers that are matched between
++ * the application and kernel side.
++ *
++ * After the application reads the CQ ring tail, it must use an
++ * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
++ * before writing the tail (using smp_load_acquire to read the tail will
++ * do). It also needs a smp_mb() before updating CQ head (ordering the
++ * entry load(s) with the head store), pairing with an implicit barrier
++ * through a control-dependency in io_get_cqe (smp_store_release to
++ * store head will do). Failure to do so could lead to reading invalid
++ * CQ entries.
++ *
++ * Likewise, the application must use an appropriate smp_wmb() before
++ * writing the SQ tail (ordering SQ entry stores with the tail store),
++ * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
++ * to store the tail will do). And it needs a barrier ordering the SQ
++ * head load before writing new SQ entries (smp_load_acquire to read
++ * head will do).
++ *
++ * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
++ * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
++ * updating the SQ tail; a full memory barrier smp_mb() is needed
++ * between.
++ *
++ * Also see the examples in the liburing library:
++ *
++ *	git://git.kernel.dk/liburing
++ *
++ * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
++ * from data shared between the kernel and application. This is done both
++ * for ordering purposes, but also to ensure that once a value is loaded from
++ * data that the application could potentially modify, it remains stable.
++ *
++ * Copyright (C) 2018-2019 Jens Axboe
++ * Copyright (c) 2018-2019 Christoph Hellwig
++ */
++#include <linux/kernel.h>
++#include <linux/init.h>
++#include <linux/errno.h>
++#include <linux/syscalls.h>
++#include <linux/compat.h>
++#include <net/compat.h>
++#include <linux/refcount.h>
++#include <linux/uio.h>
++#include <linux/bits.h>
++
++#include <linux/sched/signal.h>
++#include <linux/fs.h>
++#include <linux/file.h>
++#include <linux/fdtable.h>
++#include <linux/mm.h>
++#include <linux/mman.h>
++#include <linux/percpu.h>
++#include <linux/slab.h>
++#include <linux/blkdev.h>
++#include <linux/bvec.h>
++#include <linux/net.h>
++#include <net/sock.h>
++#include <net/af_unix.h>
++#include <net/scm.h>
++#include <linux/anon_inodes.h>
++#include <linux/sched/mm.h>
++#include <linux/uaccess.h>
++#include <linux/nospec.h>
++#include <linux/sizes.h>
++#include <linux/hugetlb.h>
++#include <linux/highmem.h>
++#include <linux/namei.h>
++#include <linux/fsnotify.h>
++#include <linux/fadvise.h>
++#include <linux/eventpoll.h>
++#include <linux/splice.h>
++#include <linux/task_work.h>
++#include <linux/pagemap.h>
++#include <linux/io_uring.h>
++#include <linux/tracehook.h>
++
++#define CREATE_TRACE_POINTS
++#include <trace/events/io_uring.h>
++
++#include <uapi/linux/io_uring.h>
++
++#include "../fs/internal.h"
++#include "io-wq.h"
++
++#define IORING_MAX_ENTRIES	32768
++#define IORING_MAX_CQ_ENTRIES	(2 * IORING_MAX_ENTRIES)
++#define IORING_SQPOLL_CAP_ENTRIES_VALUE 8
++
++/* only define max */
++#define IORING_MAX_FIXED_FILES	(1U << 15)
++#define IORING_MAX_RESTRICTIONS	(IORING_RESTRICTION_LAST + \
++				 IORING_REGISTER_LAST + IORING_OP_LAST)
++
++#define IO_RSRC_TAG_TABLE_SHIFT	(PAGE_SHIFT - 3)
++#define IO_RSRC_TAG_TABLE_MAX	(1U << IO_RSRC_TAG_TABLE_SHIFT)
++#define IO_RSRC_TAG_TABLE_MASK	(IO_RSRC_TAG_TABLE_MAX - 1)
++
++#define IORING_MAX_REG_BUFFERS	(1U << 14)
++
++#define SQE_VALID_FLAGS	(IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK|	\
++				IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
++				IOSQE_BUFFER_SELECT)
++#define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
++				REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS)
++
++#define IO_TCTX_REFS_CACHE_NR	(1U << 10)
++
++struct io_uring {
++	u32 head ____cacheline_aligned_in_smp;
++	u32 tail ____cacheline_aligned_in_smp;
++};
++
++/*
++ * This data is shared with the application through the mmap at offsets
++ * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
++ *
++ * The offsets to the member fields are published through struct
++ * io_sqring_offsets when calling io_uring_setup.
++ */
++struct io_rings {
++	/*
++	 * Head and tail offsets into the ring; the offsets need to be
++	 * masked to get valid indices.
++	 *
++	 * The kernel controls head of the sq ring and the tail of the cq ring,
++	 * and the application controls tail of the sq ring and the head of the
++	 * cq ring.
++	 */
++	struct io_uring		sq, cq;
++	/*
++	 * Bitmasks to apply to head and tail offsets (constant, equals
++	 * ring_entries - 1)
++	 */
++	u32			sq_ring_mask, cq_ring_mask;
++	/* Ring sizes (constant, power of 2) */
++	u32			sq_ring_entries, cq_ring_entries;
++	/*
++	 * Number of invalid entries dropped by the kernel due to
++	 * invalid index stored in array
++	 *
++	 * Written by the kernel, shouldn't be modified by the
++	 * application (i.e. get number of "new events" by comparing to
++	 * cached value).
++	 *
++	 * After a new SQ head value was read by the application this
++	 * counter includes all submissions that were dropped reaching
++	 * the new SQ head (and possibly more).
++	 */
++	u32			sq_dropped;
++	/*
++	 * Runtime SQ flags
++	 *
++	 * Written by the kernel, shouldn't be modified by the
++	 * application.
++	 *
++	 * The application needs a full memory barrier before checking
++	 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
++	 */
++	u32			sq_flags;
++	/*
++	 * Runtime CQ flags
++	 *
++	 * Written by the application, shouldn't be modified by the
++	 * kernel.
++	 */
++	u32			cq_flags;
++	/*
++	 * Number of completion events lost because the queue was full;
++	 * this should be avoided by the application by making sure
++	 * there are not more requests pending than there is space in
++	 * the completion queue.
++	 *
++	 * Written by the kernel, shouldn't be modified by the
++	 * application (i.e. get number of "new events" by comparing to
++	 * cached value).
++	 *
++	 * As completion events come in out of order this counter is not
++	 * ordered with any other data.
++	 */
++	u32			cq_overflow;
++	/*
++	 * Ring buffer of completion events.
++	 *
++	 * The kernel writes completion events fresh every time they are
++	 * produced, so the application is allowed to modify pending
++	 * entries.
++	 */
++	struct io_uring_cqe	cqes[] ____cacheline_aligned_in_smp;
++};
++
++enum io_uring_cmd_flags {
++	IO_URING_F_NONBLOCK		= 1,
++	IO_URING_F_COMPLETE_DEFER	= 2,
++};
++
++struct io_mapped_ubuf {
++	u64		ubuf;
++	u64		ubuf_end;
++	unsigned int	nr_bvecs;
++	unsigned long	acct_pages;
++	struct bio_vec	bvec[];
++};
++
++struct io_ring_ctx;
++
++struct io_overflow_cqe {
++	struct io_uring_cqe cqe;
++	struct list_head list;
++};
++
++struct io_fixed_file {
++	/* file * with additional FFS_* flags */
++	unsigned long file_ptr;
++};
++
++struct io_rsrc_put {
++	struct list_head list;
++	u64 tag;
++	union {
++		void *rsrc;
++		struct file *file;
++		struct io_mapped_ubuf *buf;
++	};
++};
++
++struct io_file_table {
++	struct io_fixed_file *files;
++};
++
++struct io_rsrc_node {
++	struct percpu_ref		refs;
++	struct list_head		node;
++	struct list_head		rsrc_list;
++	struct io_rsrc_data		*rsrc_data;
++	struct llist_node		llist;
++	bool				done;
++};
++
++typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
++
++struct io_rsrc_data {
++	struct io_ring_ctx		*ctx;
++
++	u64				**tags;
++	unsigned int			nr;
++	rsrc_put_fn			*do_put;
++	atomic_t			refs;
++	struct completion		done;
++	bool				quiesce;
++};
++
++struct io_buffer {
++	struct list_head list;
++	__u64 addr;
++	__u32 len;
++	__u16 bid;
++};
++
++struct io_restriction {
++	DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
++	DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
++	u8 sqe_flags_allowed;
++	u8 sqe_flags_required;
++	bool registered;
++};
++
++enum {
++	IO_SQ_THREAD_SHOULD_STOP = 0,
++	IO_SQ_THREAD_SHOULD_PARK,
++};
++
++struct io_sq_data {
++	refcount_t		refs;
++	atomic_t		park_pending;
++	struct mutex		lock;
++
++	/* ctx's that are using this sqd */
++	struct list_head	ctx_list;
++
++	struct task_struct	*thread;
++	struct wait_queue_head	wait;
++
++	unsigned		sq_thread_idle;
++	int			sq_cpu;
++	pid_t			task_pid;
++	pid_t			task_tgid;
++
++	unsigned long		state;
++	struct completion	exited;
++};
++
++#define IO_COMPL_BATCH			32
++#define IO_REQ_CACHE_SIZE		32
++#define IO_REQ_ALLOC_BATCH		8
++
++struct io_submit_link {
++	struct io_kiocb		*head;
++	struct io_kiocb		*last;
++};
++
++struct io_submit_state {
++	struct blk_plug		plug;
++	struct io_submit_link	link;
++
++	/*
++	 * io_kiocb alloc cache
++	 */
++	void			*reqs[IO_REQ_CACHE_SIZE];
++	unsigned int		free_reqs;
++
++	bool			plug_started;
++
++	/*
++	 * Batch completion logic
++	 */
++	struct io_kiocb		*compl_reqs[IO_COMPL_BATCH];
++	unsigned int		compl_nr;
++	/* inline/task_work completion list, under ->uring_lock */
++	struct list_head	free_list;
++
++	unsigned int		ios_left;
++};
++
++struct io_ring_ctx {
++	/* const or read-mostly hot data */
++	struct {
++		struct percpu_ref	refs;
++
++		struct io_rings		*rings;
++		unsigned int		flags;
++		unsigned int		compat: 1;
++		unsigned int		drain_next: 1;
++		unsigned int		eventfd_async: 1;
++		unsigned int		restricted: 1;
++		unsigned int		off_timeout_used: 1;
++		unsigned int		drain_active: 1;
++	} ____cacheline_aligned_in_smp;
++
++	/* submission data */
++	struct {
++		struct mutex		uring_lock;
++
++		/*
++		 * Ring buffer of indices into array of io_uring_sqe, which is
++		 * mmapped by the application using the IORING_OFF_SQES offset.
++		 *
++		 * This indirection could e.g. be used to assign fixed
++		 * io_uring_sqe entries to operations and only submit them to
++		 * the queue when needed.
++		 *
++		 * The kernel modifies neither the indices array nor the entries
++		 * array.
++		 */
++		u32			*sq_array;
++		struct io_uring_sqe	*sq_sqes;
++		unsigned		cached_sq_head;
++		unsigned		sq_entries;
++		struct list_head	defer_list;
++
++		/*
++		 * Fixed resources fast path, should be accessed only under
++		 * uring_lock, and updated through io_uring_register(2)
++		 */
++		struct io_rsrc_node	*rsrc_node;
++		struct io_file_table	file_table;
++		unsigned		nr_user_files;
++		unsigned		nr_user_bufs;
++		struct io_mapped_ubuf	**user_bufs;
++
++		struct io_submit_state	submit_state;
++		struct list_head	timeout_list;
++		struct list_head	ltimeout_list;
++		struct list_head	cq_overflow_list;
++		struct xarray		io_buffers;
++		struct xarray		personalities;
++		u32			pers_next;
++		unsigned		sq_thread_idle;
++	} ____cacheline_aligned_in_smp;
++
++	/* IRQ completion list, under ->completion_lock */
++	struct list_head	locked_free_list;
++	unsigned int		locked_free_nr;
++
++	const struct cred	*sq_creds;	/* cred used for __io_sq_thread() */
++	struct io_sq_data	*sq_data;	/* if using sq thread polling */
++
++	struct wait_queue_head	sqo_sq_wait;
++	struct list_head	sqd_list;
++
++	unsigned long		check_cq_overflow;
++
++	struct {
++		unsigned		cached_cq_tail;
++		unsigned		cq_entries;
++		struct eventfd_ctx	*cq_ev_fd;
++		struct wait_queue_head	poll_wait;
++		struct wait_queue_head	cq_wait;
++		unsigned		cq_extra;
++		atomic_t		cq_timeouts;
++		unsigned		cq_last_tm_flush;
++	} ____cacheline_aligned_in_smp;
++
++	struct {
++		spinlock_t		completion_lock;
++
++		spinlock_t		timeout_lock;
++
++		/*
++		 * ->iopoll_list is protected by the ctx->uring_lock for
++		 * io_uring instances that don't use IORING_SETUP_SQPOLL.
++		 * For SQPOLL, only the single threaded io_sq_thread() will
++		 * manipulate the list, hence no extra locking is needed there.
++		 */
++		struct list_head	iopoll_list;
++		struct hlist_head	*cancel_hash;
++		unsigned		cancel_hash_bits;
++		bool			poll_multi_queue;
++	} ____cacheline_aligned_in_smp;
++
++	struct io_restriction		restrictions;
++
++	/* slow path rsrc auxilary data, used by update/register */
++	struct {
++		struct io_rsrc_node		*rsrc_backup_node;
++		struct io_mapped_ubuf		*dummy_ubuf;
++		struct io_rsrc_data		*file_data;
++		struct io_rsrc_data		*buf_data;
++
++		struct delayed_work		rsrc_put_work;
++		struct llist_head		rsrc_put_llist;
++		struct list_head		rsrc_ref_list;
++		spinlock_t			rsrc_ref_lock;
++	};
++
++	/* Keep this last, we don't need it for the fast path */
++	struct {
++		#if defined(CONFIG_UNIX)
++			struct socket		*ring_sock;
++		#endif
++		/* hashed buffered write serialization */
++		struct io_wq_hash		*hash_map;
++
++		/* Only used for accounting purposes */
++		struct user_struct		*user;
++		struct mm_struct		*mm_account;
++
++		/* ctx exit and cancelation */
++		struct llist_head		fallback_llist;
++		struct delayed_work		fallback_work;
++		struct work_struct		exit_work;
++		struct list_head		tctx_list;
++		struct completion		ref_comp;
++		u32				iowq_limits[2];
++		bool				iowq_limits_set;
++	};
++};
++
++struct io_uring_task {
++	/* submission side */
++	int			cached_refs;
++	struct xarray		xa;
++	struct wait_queue_head	wait;
++	const struct io_ring_ctx *last;
++	struct io_wq		*io_wq;
++	struct percpu_counter	inflight;
++	atomic_t		inflight_tracked;
++	atomic_t		in_idle;
++
++	spinlock_t		task_lock;
++	struct io_wq_work_list	task_list;
++	struct callback_head	task_work;
++	bool			task_running;
++};
++
++/*
++ * First field must be the file pointer in all the
++ * iocb unions! See also 'struct kiocb' in <linux/fs.h>
++ */
++struct io_poll_iocb {
++	struct file			*file;
++	struct wait_queue_head		*head;
++	__poll_t			events;
++	struct wait_queue_entry		wait;
++};
++
++struct io_poll_update {
++	struct file			*file;
++	u64				old_user_data;
++	u64				new_user_data;
++	__poll_t			events;
++	bool				update_events;
++	bool				update_user_data;
++};
++
++struct io_close {
++	struct file			*file;
++	int				fd;
++	u32				file_slot;
++};
++
++struct io_timeout_data {
++	struct io_kiocb			*req;
++	struct hrtimer			timer;
++	struct timespec64		ts;
++	enum hrtimer_mode		mode;
++	u32				flags;
++};
++
++struct io_accept {
++	struct file			*file;
++	struct sockaddr __user		*addr;
++	int __user			*addr_len;
++	int				flags;
++	u32				file_slot;
++	unsigned long			nofile;
++};
++
++struct io_sync {
++	struct file			*file;
++	loff_t				len;
++	loff_t				off;
++	int				flags;
++	int				mode;
++};
++
++struct io_cancel {
++	struct file			*file;
++	u64				addr;
++};
++
++struct io_timeout {
++	struct file			*file;
++	u32				off;
++	u32				target_seq;
++	struct list_head		list;
++	/* head of the link, used by linked timeouts only */
++	struct io_kiocb			*head;
++	/* for linked completions */
++	struct io_kiocb			*prev;
++};
++
++struct io_timeout_rem {
++	struct file			*file;
++	u64				addr;
++
++	/* timeout update */
++	struct timespec64		ts;
++	u32				flags;
++	bool				ltimeout;
++};
++
++struct io_rw {
++	/* NOTE: kiocb has the file as the first member, so don't do it here */
++	struct kiocb			kiocb;
++	u64				addr;
++	u64				len;
++};
++
++struct io_connect {
++	struct file			*file;
++	struct sockaddr __user		*addr;
++	int				addr_len;
++};
++
++struct io_sr_msg {
++	struct file			*file;
++	union {
++		struct compat_msghdr __user	*umsg_compat;
++		struct user_msghdr __user	*umsg;
++		void __user			*buf;
++	};
++	int				msg_flags;
++	int				bgid;
++	size_t				len;
++	struct io_buffer		*kbuf;
++};
++
++struct io_open {
++	struct file			*file;
++	int				dfd;
++	u32				file_slot;
++	struct filename			*filename;
++	struct open_how			how;
++	unsigned long			nofile;
++};
++
++struct io_rsrc_update {
++	struct file			*file;
++	u64				arg;
++	u32				nr_args;
++	u32				offset;
++};
++
++struct io_fadvise {
++	struct file			*file;
++	u64				offset;
++	u32				len;
++	u32				advice;
++};
++
++struct io_madvise {
++	struct file			*file;
++	u64				addr;
++	u32				len;
++	u32				advice;
++};
++
++struct io_epoll {
++	struct file			*file;
++	int				epfd;
++	int				op;
++	int				fd;
++	struct epoll_event		event;
++};
++
++struct io_splice {
++	struct file			*file_out;
++	loff_t				off_out;
++	loff_t				off_in;
++	u64				len;
++	int				splice_fd_in;
++	unsigned int			flags;
++};
++
++struct io_provide_buf {
++	struct file			*file;
++	__u64				addr;
++	__u32				len;
++	__u32				bgid;
++	__u16				nbufs;
++	__u16				bid;
++};
++
++struct io_statx {
++	struct file			*file;
++	int				dfd;
++	unsigned int			mask;
++	unsigned int			flags;
++	const char __user		*filename;
++	struct statx __user		*buffer;
++};
++
++struct io_shutdown {
++	struct file			*file;
++	int				how;
++};
++
++struct io_rename {
++	struct file			*file;
++	int				old_dfd;
++	int				new_dfd;
++	struct filename			*oldpath;
++	struct filename			*newpath;
++	int				flags;
++};
++
++struct io_unlink {
++	struct file			*file;
++	int				dfd;
++	int				flags;
++	struct filename			*filename;
++};
++
++struct io_mkdir {
++	struct file			*file;
++	int				dfd;
++	umode_t				mode;
++	struct filename			*filename;
++};
++
++struct io_symlink {
++	struct file			*file;
++	int				new_dfd;
++	struct filename			*oldpath;
++	struct filename			*newpath;
++};
++
++struct io_hardlink {
++	struct file			*file;
++	int				old_dfd;
++	int				new_dfd;
++	struct filename			*oldpath;
++	struct filename			*newpath;
++	int				flags;
++};
++
++struct io_completion {
++	struct file			*file;
++	u32				cflags;
++};
++
++struct io_async_connect {
++	struct sockaddr_storage		address;
++};
++
++struct io_async_msghdr {
++	struct iovec			fast_iov[UIO_FASTIOV];
++	/* points to an allocated iov, if NULL we use fast_iov instead */
++	struct iovec			*free_iov;
++	struct sockaddr __user		*uaddr;
++	struct msghdr			msg;
++	struct sockaddr_storage		addr;
++};
++
++struct io_async_rw {
++	struct iovec			fast_iov[UIO_FASTIOV];
++	const struct iovec		*free_iovec;
++	struct iov_iter			iter;
++	struct iov_iter_state		iter_state;
++	size_t				bytes_done;
++	struct wait_page_queue		wpq;
++};
++
++enum {
++	REQ_F_FIXED_FILE_BIT	= IOSQE_FIXED_FILE_BIT,
++	REQ_F_IO_DRAIN_BIT	= IOSQE_IO_DRAIN_BIT,
++	REQ_F_LINK_BIT		= IOSQE_IO_LINK_BIT,
++	REQ_F_HARDLINK_BIT	= IOSQE_IO_HARDLINK_BIT,
++	REQ_F_FORCE_ASYNC_BIT	= IOSQE_ASYNC_BIT,
++	REQ_F_BUFFER_SELECT_BIT	= IOSQE_BUFFER_SELECT_BIT,
++
++	/* first byte is taken by user flags, shift it to not overlap */
++	REQ_F_FAIL_BIT		= 8,
++	REQ_F_INFLIGHT_BIT,
++	REQ_F_CUR_POS_BIT,
++	REQ_F_NOWAIT_BIT,
++	REQ_F_LINK_TIMEOUT_BIT,
++	REQ_F_NEED_CLEANUP_BIT,
++	REQ_F_POLLED_BIT,
++	REQ_F_BUFFER_SELECTED_BIT,
++	REQ_F_COMPLETE_INLINE_BIT,
++	REQ_F_REISSUE_BIT,
++	REQ_F_CREDS_BIT,
++	REQ_F_REFCOUNT_BIT,
++	REQ_F_ARM_LTIMEOUT_BIT,
++	/* keep async read/write and isreg together and in order */
++	REQ_F_NOWAIT_READ_BIT,
++	REQ_F_NOWAIT_WRITE_BIT,
++	REQ_F_ISREG_BIT,
++
++	/* not a real bit, just to check we're not overflowing the space */
++	__REQ_F_LAST_BIT,
++};
++
++enum {
++	/* ctx owns file */
++	REQ_F_FIXED_FILE	= BIT(REQ_F_FIXED_FILE_BIT),
++	/* drain existing IO first */
++	REQ_F_IO_DRAIN		= BIT(REQ_F_IO_DRAIN_BIT),
++	/* linked sqes */
++	REQ_F_LINK		= BIT(REQ_F_LINK_BIT),
++	/* doesn't sever on completion < 0 */
++	REQ_F_HARDLINK		= BIT(REQ_F_HARDLINK_BIT),
++	/* IOSQE_ASYNC */
++	REQ_F_FORCE_ASYNC	= BIT(REQ_F_FORCE_ASYNC_BIT),
++	/* IOSQE_BUFFER_SELECT */
++	REQ_F_BUFFER_SELECT	= BIT(REQ_F_BUFFER_SELECT_BIT),
++
++	/* fail rest of links */
++	REQ_F_FAIL		= BIT(REQ_F_FAIL_BIT),
++	/* on inflight list, should be cancelled and waited on exit reliably */
++	REQ_F_INFLIGHT		= BIT(REQ_F_INFLIGHT_BIT),
++	/* read/write uses file position */
++	REQ_F_CUR_POS		= BIT(REQ_F_CUR_POS_BIT),
++	/* must not punt to workers */
++	REQ_F_NOWAIT		= BIT(REQ_F_NOWAIT_BIT),
++	/* has or had linked timeout */
++	REQ_F_LINK_TIMEOUT	= BIT(REQ_F_LINK_TIMEOUT_BIT),
++	/* needs cleanup */
++	REQ_F_NEED_CLEANUP	= BIT(REQ_F_NEED_CLEANUP_BIT),
++	/* already went through poll handler */
++	REQ_F_POLLED		= BIT(REQ_F_POLLED_BIT),
++	/* buffer already selected */
++	REQ_F_BUFFER_SELECTED	= BIT(REQ_F_BUFFER_SELECTED_BIT),
++	/* completion is deferred through io_comp_state */
++	REQ_F_COMPLETE_INLINE	= BIT(REQ_F_COMPLETE_INLINE_BIT),
++	/* caller should reissue async */
++	REQ_F_REISSUE		= BIT(REQ_F_REISSUE_BIT),
++	/* supports async reads */
++	REQ_F_NOWAIT_READ	= BIT(REQ_F_NOWAIT_READ_BIT),
++	/* supports async writes */
++	REQ_F_NOWAIT_WRITE	= BIT(REQ_F_NOWAIT_WRITE_BIT),
++	/* regular file */
++	REQ_F_ISREG		= BIT(REQ_F_ISREG_BIT),
++	/* has creds assigned */
++	REQ_F_CREDS		= BIT(REQ_F_CREDS_BIT),
++	/* skip refcounting if not set */
++	REQ_F_REFCOUNT		= BIT(REQ_F_REFCOUNT_BIT),
++	/* there is a linked timeout that has to be armed */
++	REQ_F_ARM_LTIMEOUT	= BIT(REQ_F_ARM_LTIMEOUT_BIT),
++};
++
++struct async_poll {
++	struct io_poll_iocb	poll;
++	struct io_poll_iocb	*double_poll;
++};
++
++typedef void (*io_req_tw_func_t)(struct io_kiocb *req, bool *locked);
++
++struct io_task_work {
++	union {
++		struct io_wq_work_node	node;
++		struct llist_node	fallback_node;
++	};
++	io_req_tw_func_t		func;
++};
++
++enum {
++	IORING_RSRC_FILE		= 0,
++	IORING_RSRC_BUFFER		= 1,
++};
++
++/*
++ * NOTE! Each of the iocb union members has the file pointer
++ * as the first entry in their struct definition. So you can
++ * access the file pointer through any of the sub-structs,
++ * or directly as just 'ki_filp' in this struct.
++ */
++struct io_kiocb {
++	union {
++		struct file		*file;
++		struct io_rw		rw;
++		struct io_poll_iocb	poll;
++		struct io_poll_update	poll_update;
++		struct io_accept	accept;
++		struct io_sync		sync;
++		struct io_cancel	cancel;
++		struct io_timeout	timeout;
++		struct io_timeout_rem	timeout_rem;
++		struct io_connect	connect;
++		struct io_sr_msg	sr_msg;
++		struct io_open		open;
++		struct io_close		close;
++		struct io_rsrc_update	rsrc_update;
++		struct io_fadvise	fadvise;
++		struct io_madvise	madvise;
++		struct io_epoll		epoll;
++		struct io_splice	splice;
++		struct io_provide_buf	pbuf;
++		struct io_statx		statx;
++		struct io_shutdown	shutdown;
++		struct io_rename	rename;
++		struct io_unlink	unlink;
++		struct io_mkdir		mkdir;
++		struct io_symlink	symlink;
++		struct io_hardlink	hardlink;
++		/* use only after cleaning per-op data, see io_clean_op() */
++		struct io_completion	compl;
++	};
++
++	/* opcode allocated if it needs to store data for async defer */
++	void				*async_data;
++	u8				opcode;
++	/* polled IO has completed */
++	u8				iopoll_completed;
++
++	u16				buf_index;
++	u32				result;
++
++	struct io_ring_ctx		*ctx;
++	unsigned int			flags;
++	atomic_t			refs;
++	struct task_struct		*task;
++	u64				user_data;
++
++	struct io_kiocb			*link;
++	struct percpu_ref		*fixed_rsrc_refs;
++
++	/* used with ctx->iopoll_list with reads/writes */
++	struct list_head		inflight_entry;
++	struct io_task_work		io_task_work;
++	/* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
++	struct hlist_node		hash_node;
++	struct async_poll		*apoll;
++	struct io_wq_work		work;
++	const struct cred		*creds;
++
++	/* store used ubuf, so we can prevent reloading */
++	struct io_mapped_ubuf		*imu;
++	/* stores selected buf, valid IFF REQ_F_BUFFER_SELECTED is set */
++	struct io_buffer		*kbuf;
++	atomic_t			poll_refs;
++};
++
++struct io_tctx_node {
++	struct list_head	ctx_node;
++	struct task_struct	*task;
++	struct io_ring_ctx	*ctx;
++};
++
++struct io_defer_entry {
++	struct list_head	list;
++	struct io_kiocb		*req;
++	u32			seq;
++};
++
++struct io_op_def {
++	/* needs req->file assigned */
++	unsigned		needs_file : 1;
++	/* hash wq insertion if file is a regular file */
++	unsigned		hash_reg_file : 1;
++	/* unbound wq insertion if file is a non-regular file */
++	unsigned		unbound_nonreg_file : 1;
++	/* opcode is not supported by this kernel */
++	unsigned		not_supported : 1;
++	/* set if opcode supports polled "wait" */
++	unsigned		pollin : 1;
++	unsigned		pollout : 1;
++	/* op supports buffer selection */
++	unsigned		buffer_select : 1;
++	/* do prep async if is going to be punted */
++	unsigned		needs_async_setup : 1;
++	/* should block plug */
++	unsigned		plug : 1;
++	/* size of async data needed, if any */
++	unsigned short		async_size;
++};
++
++static const struct io_op_def io_op_defs[] = {
++	[IORING_OP_NOP] = {},
++	[IORING_OP_READV] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollin			= 1,
++		.buffer_select		= 1,
++		.needs_async_setup	= 1,
++		.plug			= 1,
++		.async_size		= sizeof(struct io_async_rw),
++	},
++	[IORING_OP_WRITEV] = {
++		.needs_file		= 1,
++		.hash_reg_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollout		= 1,
++		.needs_async_setup	= 1,
++		.plug			= 1,
++		.async_size		= sizeof(struct io_async_rw),
++	},
++	[IORING_OP_FSYNC] = {
++		.needs_file		= 1,
++	},
++	[IORING_OP_READ_FIXED] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollin			= 1,
++		.plug			= 1,
++		.async_size		= sizeof(struct io_async_rw),
++	},
++	[IORING_OP_WRITE_FIXED] = {
++		.needs_file		= 1,
++		.hash_reg_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollout		= 1,
++		.plug			= 1,
++		.async_size		= sizeof(struct io_async_rw),
++	},
++	[IORING_OP_POLL_ADD] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++	},
++	[IORING_OP_POLL_REMOVE] = {},
++	[IORING_OP_SYNC_FILE_RANGE] = {
++		.needs_file		= 1,
++	},
++	[IORING_OP_SENDMSG] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollout		= 1,
++		.needs_async_setup	= 1,
++		.async_size		= sizeof(struct io_async_msghdr),
++	},
++	[IORING_OP_RECVMSG] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollin			= 1,
++		.buffer_select		= 1,
++		.needs_async_setup	= 1,
++		.async_size		= sizeof(struct io_async_msghdr),
++	},
++	[IORING_OP_TIMEOUT] = {
++		.async_size		= sizeof(struct io_timeout_data),
++	},
++	[IORING_OP_TIMEOUT_REMOVE] = {
++		/* used by timeout updates' prep() */
++	},
++	[IORING_OP_ACCEPT] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollin			= 1,
++	},
++	[IORING_OP_ASYNC_CANCEL] = {},
++	[IORING_OP_LINK_TIMEOUT] = {
++		.async_size		= sizeof(struct io_timeout_data),
++	},
++	[IORING_OP_CONNECT] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollout		= 1,
++		.needs_async_setup	= 1,
++		.async_size		= sizeof(struct io_async_connect),
++	},
++	[IORING_OP_FALLOCATE] = {
++		.needs_file		= 1,
++	},
++	[IORING_OP_OPENAT] = {},
++	[IORING_OP_CLOSE] = {},
++	[IORING_OP_FILES_UPDATE] = {},
++	[IORING_OP_STATX] = {},
++	[IORING_OP_READ] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollin			= 1,
++		.buffer_select		= 1,
++		.plug			= 1,
++		.async_size		= sizeof(struct io_async_rw),
++	},
++	[IORING_OP_WRITE] = {
++		.needs_file		= 1,
++		.hash_reg_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollout		= 1,
++		.plug			= 1,
++		.async_size		= sizeof(struct io_async_rw),
++	},
++	[IORING_OP_FADVISE] = {
++		.needs_file		= 1,
++	},
++	[IORING_OP_MADVISE] = {},
++	[IORING_OP_SEND] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollout		= 1,
++	},
++	[IORING_OP_RECV] = {
++		.needs_file		= 1,
++		.unbound_nonreg_file	= 1,
++		.pollin			= 1,
++		.buffer_select		= 1,
++	},
++	[IORING_OP_OPENAT2] = {
++	},
++	[IORING_OP_EPOLL_CTL] = {
++		.unbound_nonreg_file	= 1,
++	},
++	[IORING_OP_SPLICE] = {
++		.needs_file		= 1,
++		.hash_reg_file		= 1,
++		.unbound_nonreg_file	= 1,
++	},
++	[IORING_OP_PROVIDE_BUFFERS] = {},
++	[IORING_OP_REMOVE_BUFFERS] = {},
++	[IORING_OP_TEE] = {
++		.needs_file		= 1,
++		.hash_reg_file		= 1,
++		.unbound_nonreg_file	= 1,
++	},
++	[IORING_OP_SHUTDOWN] = {
++		.needs_file		= 1,
++	},
++	[IORING_OP_RENAMEAT] = {},
++	[IORING_OP_UNLINKAT] = {},
++	[IORING_OP_MKDIRAT] = {},
++	[IORING_OP_SYMLINKAT] = {},
++	[IORING_OP_LINKAT] = {},
++};
++
++/* requests with any of those set should undergo io_disarm_next() */
++#define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
++
++static bool io_disarm_next(struct io_kiocb *req);
++static void io_uring_del_tctx_node(unsigned long index);
++static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
++					 struct task_struct *task,
++					 bool cancel_all);
++static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
++
++static void io_fill_cqe_req(struct io_kiocb *req, s32 res, u32 cflags);
++
++static void io_put_req(struct io_kiocb *req);
++static void io_put_req_deferred(struct io_kiocb *req);
++static void io_dismantle_req(struct io_kiocb *req);
++static void io_queue_linked_timeout(struct io_kiocb *req);
++static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
++				     struct io_uring_rsrc_update2 *up,
++				     unsigned nr_args);
++static void io_clean_op(struct io_kiocb *req);
++static struct file *io_file_get(struct io_ring_ctx *ctx,
++				struct io_kiocb *req, int fd, bool fixed);
++static void __io_queue_sqe(struct io_kiocb *req);
++static void io_rsrc_put_work(struct work_struct *work);
++
++static void io_req_task_queue(struct io_kiocb *req);
++static void io_submit_flush_completions(struct io_ring_ctx *ctx);
++static int io_req_prep_async(struct io_kiocb *req);
++
++static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
++				 unsigned int issue_flags, u32 slot_index);
++static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags);
++
++static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer);
++
++static struct kmem_cache *req_cachep;
++
++static const struct file_operations io_uring_fops;
++
++struct sock *io_uring_get_socket(struct file *file)
++{
++#if defined(CONFIG_UNIX)
++	if (file->f_op == &io_uring_fops) {
++		struct io_ring_ctx *ctx = file->private_data;
++
++		return ctx->ring_sock->sk;
++	}
++#endif
++	return NULL;
++}
++EXPORT_SYMBOL(io_uring_get_socket);
++
++static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked)
++{
++	if (!*locked) {
++		mutex_lock(&ctx->uring_lock);
++		*locked = true;
++	}
++}
++
++#define io_for_each_link(pos, head) \
++	for (pos = (head); pos; pos = pos->link)
++
++/*
++ * Shamelessly stolen from the mm implementation of page reference checking,
++ * see commit f958d7b528b1 for details.
++ */
++#define req_ref_zero_or_close_to_overflow(req)	\
++	((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
++
++static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
++{
++	WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
++	return atomic_inc_not_zero(&req->refs);
++}
++
++static inline bool req_ref_put_and_test(struct io_kiocb *req)
++{
++	if (likely(!(req->flags & REQ_F_REFCOUNT)))
++		return true;
++
++	WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
++	return atomic_dec_and_test(&req->refs);
++}
++
++static inline void req_ref_get(struct io_kiocb *req)
++{
++	WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
++	WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
++	atomic_inc(&req->refs);
++}
++
++static inline void __io_req_set_refcount(struct io_kiocb *req, int nr)
++{
++	if (!(req->flags & REQ_F_REFCOUNT)) {
++		req->flags |= REQ_F_REFCOUNT;
++		atomic_set(&req->refs, nr);
++	}
++}
++
++static inline void io_req_set_refcount(struct io_kiocb *req)
++{
++	__io_req_set_refcount(req, 1);
++}
++
++static inline void io_req_set_rsrc_node(struct io_kiocb *req)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	if (!req->fixed_rsrc_refs) {
++		req->fixed_rsrc_refs = &ctx->rsrc_node->refs;
++		percpu_ref_get(req->fixed_rsrc_refs);
++	}
++}
++
++static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl)
++{
++	bool got = percpu_ref_tryget(ref);
++
++	/* already at zero, wait for ->release() */
++	if (!got)
++		wait_for_completion(compl);
++	percpu_ref_resurrect(ref);
++	if (got)
++		percpu_ref_put(ref);
++}
++
++static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
++			  bool cancel_all)
++	__must_hold(&req->ctx->timeout_lock)
++{
++	struct io_kiocb *req;
++
++	if (task && head->task != task)
++		return false;
++	if (cancel_all)
++		return true;
++
++	io_for_each_link(req, head) {
++		if (req->flags & REQ_F_INFLIGHT)
++			return true;
++	}
++	return false;
++}
++
++static bool io_match_linked(struct io_kiocb *head)
++{
++	struct io_kiocb *req;
++
++	io_for_each_link(req, head) {
++		if (req->flags & REQ_F_INFLIGHT)
++			return true;
++	}
++	return false;
++}
++
++/*
++ * As io_match_task() but protected against racing with linked timeouts.
++ * User must not hold timeout_lock.
++ */
++static bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
++			       bool cancel_all)
++{
++	bool matched;
++
++	if (task && head->task != task)
++		return false;
++	if (cancel_all)
++		return true;
++
++	if (head->flags & REQ_F_LINK_TIMEOUT) {
++		struct io_ring_ctx *ctx = head->ctx;
++
++		/* protect against races with linked timeouts */
++		spin_lock_irq(&ctx->timeout_lock);
++		matched = io_match_linked(head);
++		spin_unlock_irq(&ctx->timeout_lock);
++	} else {
++		matched = io_match_linked(head);
++	}
++	return matched;
++}
++
++static inline void req_set_fail(struct io_kiocb *req)
++{
++	req->flags |= REQ_F_FAIL;
++}
++
++static inline void req_fail_link_node(struct io_kiocb *req, int res)
++{
++	req_set_fail(req);
++	req->result = res;
++}
++
++static void io_ring_ctx_ref_free(struct percpu_ref *ref)
++{
++	struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
++
++	complete(&ctx->ref_comp);
++}
++
++static inline bool io_is_timeout_noseq(struct io_kiocb *req)
++{
++	return !req->timeout.off;
++}
++
++static void io_fallback_req_func(struct work_struct *work)
++{
++	struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
++						fallback_work.work);
++	struct llist_node *node = llist_del_all(&ctx->fallback_llist);
++	struct io_kiocb *req, *tmp;
++	bool locked = false;
++
++	percpu_ref_get(&ctx->refs);
++	llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node)
++		req->io_task_work.func(req, &locked);
++
++	if (locked) {
++		if (ctx->submit_state.compl_nr)
++			io_submit_flush_completions(ctx);
++		mutex_unlock(&ctx->uring_lock);
++	}
++	percpu_ref_put(&ctx->refs);
++
++}
++
++static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
++{
++	struct io_ring_ctx *ctx;
++	int hash_bits;
++
++	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
++	if (!ctx)
++		return NULL;
++
++	/*
++	 * Use 5 bits less than the max cq entries, that should give us around
++	 * 32 entries per hash list if totally full and uniformly spread.
++	 */
++	hash_bits = ilog2(p->cq_entries);
++	hash_bits -= 5;
++	if (hash_bits <= 0)
++		hash_bits = 1;
++	ctx->cancel_hash_bits = hash_bits;
++	ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
++					GFP_KERNEL);
++	if (!ctx->cancel_hash)
++		goto err;
++	__hash_init(ctx->cancel_hash, 1U << hash_bits);
++
++	ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL);
++	if (!ctx->dummy_ubuf)
++		goto err;
++	/* set invalid range, so io_import_fixed() fails meeting it */
++	ctx->dummy_ubuf->ubuf = -1UL;
++
++	if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
++			    PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
++		goto err;
++
++	ctx->flags = p->flags;
++	init_waitqueue_head(&ctx->sqo_sq_wait);
++	INIT_LIST_HEAD(&ctx->sqd_list);
++	init_waitqueue_head(&ctx->poll_wait);
++	INIT_LIST_HEAD(&ctx->cq_overflow_list);
++	init_completion(&ctx->ref_comp);
++	xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
++	xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
++	mutex_init(&ctx->uring_lock);
++	init_waitqueue_head(&ctx->cq_wait);
++	spin_lock_init(&ctx->completion_lock);
++	spin_lock_init(&ctx->timeout_lock);
++	INIT_LIST_HEAD(&ctx->iopoll_list);
++	INIT_LIST_HEAD(&ctx->defer_list);
++	INIT_LIST_HEAD(&ctx->timeout_list);
++	INIT_LIST_HEAD(&ctx->ltimeout_list);
++	spin_lock_init(&ctx->rsrc_ref_lock);
++	INIT_LIST_HEAD(&ctx->rsrc_ref_list);
++	INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
++	init_llist_head(&ctx->rsrc_put_llist);
++	INIT_LIST_HEAD(&ctx->tctx_list);
++	INIT_LIST_HEAD(&ctx->submit_state.free_list);
++	INIT_LIST_HEAD(&ctx->locked_free_list);
++	INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func);
++	return ctx;
++err:
++	kfree(ctx->dummy_ubuf);
++	kfree(ctx->cancel_hash);
++	kfree(ctx);
++	return NULL;
++}
++
++static void io_account_cq_overflow(struct io_ring_ctx *ctx)
++{
++	struct io_rings *r = ctx->rings;
++
++	WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1);
++	ctx->cq_extra--;
++}
++
++static bool req_need_defer(struct io_kiocb *req, u32 seq)
++{
++	if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
++		struct io_ring_ctx *ctx = req->ctx;
++
++		return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail;
++	}
++
++	return false;
++}
++
++#define FFS_ASYNC_READ		0x1UL
++#define FFS_ASYNC_WRITE		0x2UL
++#ifdef CONFIG_64BIT
++#define FFS_ISREG		0x4UL
++#else
++#define FFS_ISREG		0x0UL
++#endif
++#define FFS_MASK		~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
++
++static inline bool io_req_ffs_set(struct io_kiocb *req)
++{
++	return IS_ENABLED(CONFIG_64BIT) && (req->flags & REQ_F_FIXED_FILE);
++}
++
++static void io_req_track_inflight(struct io_kiocb *req)
++{
++	if (!(req->flags & REQ_F_INFLIGHT)) {
++		req->flags |= REQ_F_INFLIGHT;
++		atomic_inc(&req->task->io_uring->inflight_tracked);
++	}
++}
++
++static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req)
++{
++	if (WARN_ON_ONCE(!req->link))
++		return NULL;
++
++	req->flags &= ~REQ_F_ARM_LTIMEOUT;
++	req->flags |= REQ_F_LINK_TIMEOUT;
++
++	/* linked timeouts should have two refs once prep'ed */
++	io_req_set_refcount(req);
++	__io_req_set_refcount(req->link, 2);
++	return req->link;
++}
++
++static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
++{
++	if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT)))
++		return NULL;
++	return __io_prep_linked_timeout(req);
++}
++
++static void io_prep_async_work(struct io_kiocb *req)
++{
++	const struct io_op_def *def = &io_op_defs[req->opcode];
++	struct io_ring_ctx *ctx = req->ctx;
++
++	if (!(req->flags & REQ_F_CREDS)) {
++		req->flags |= REQ_F_CREDS;
++		req->creds = get_current_cred();
++	}
++
++	req->work.list.next = NULL;
++	req->work.flags = 0;
++	if (req->flags & REQ_F_FORCE_ASYNC)
++		req->work.flags |= IO_WQ_WORK_CONCURRENT;
++
++	if (req->flags & REQ_F_ISREG) {
++		if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
++			io_wq_hash_work(&req->work, file_inode(req->file));
++	} else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
++		if (def->unbound_nonreg_file)
++			req->work.flags |= IO_WQ_WORK_UNBOUND;
++	}
++}
++
++static void io_prep_async_link(struct io_kiocb *req)
++{
++	struct io_kiocb *cur;
++
++	if (req->flags & REQ_F_LINK_TIMEOUT) {
++		struct io_ring_ctx *ctx = req->ctx;
++
++		spin_lock_irq(&ctx->timeout_lock);
++		io_for_each_link(cur, req)
++			io_prep_async_work(cur);
++		spin_unlock_irq(&ctx->timeout_lock);
++	} else {
++		io_for_each_link(cur, req)
++			io_prep_async_work(cur);
++	}
++}
++
++static void io_queue_async_work(struct io_kiocb *req, bool *locked)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_kiocb *link = io_prep_linked_timeout(req);
++	struct io_uring_task *tctx = req->task->io_uring;
++
++	/* must not take the lock, NULL it as a precaution */
++	locked = NULL;
++
++	BUG_ON(!tctx);
++	BUG_ON(!tctx->io_wq);
++
++	/* init ->work of the whole link before punting */
++	io_prep_async_link(req);
++
++	/*
++	 * Not expected to happen, but if we do have a bug where this _can_
++	 * happen, catch it here and ensure the request is marked as
++	 * canceled. That will make io-wq go through the usual work cancel
++	 * procedure rather than attempt to run this request (or create a new
++	 * worker for it).
++	 */
++	if (WARN_ON_ONCE(!same_thread_group(req->task, current)))
++		req->work.flags |= IO_WQ_WORK_CANCEL;
++
++	trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
++					&req->work, req->flags);
++	io_wq_enqueue(tctx->io_wq, &req->work);
++	if (link)
++		io_queue_linked_timeout(link);
++}
++
++static void io_kill_timeout(struct io_kiocb *req, int status)
++	__must_hold(&req->ctx->completion_lock)
++	__must_hold(&req->ctx->timeout_lock)
++{
++	struct io_timeout_data *io = req->async_data;
++
++	if (hrtimer_try_to_cancel(&io->timer) != -1) {
++		if (status)
++			req_set_fail(req);
++		atomic_set(&req->ctx->cq_timeouts,
++			atomic_read(&req->ctx->cq_timeouts) + 1);
++		list_del_init(&req->timeout.list);
++		io_fill_cqe_req(req, status, 0);
++		io_put_req_deferred(req);
++	}
++}
++
++static void io_queue_deferred(struct io_ring_ctx *ctx)
++{
++	while (!list_empty(&ctx->defer_list)) {
++		struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
++						struct io_defer_entry, list);
++
++		if (req_need_defer(de->req, de->seq))
++			break;
++		list_del_init(&de->list);
++		io_req_task_queue(de->req);
++		kfree(de);
++	}
++}
++
++static void io_flush_timeouts(struct io_ring_ctx *ctx)
++	__must_hold(&ctx->completion_lock)
++{
++	u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
++	struct io_kiocb *req, *tmp;
++
++	spin_lock_irq(&ctx->timeout_lock);
++	list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
++		u32 events_needed, events_got;
++
++		if (io_is_timeout_noseq(req))
++			break;
++
++		/*
++		 * Since seq can easily wrap around over time, subtract
++		 * the last seq at which timeouts were flushed before comparing.
++		 * Assuming not more than 2^31-1 events have happened since,
++		 * these subtractions won't have wrapped, so we can check if
++		 * target is in [last_seq, current_seq] by comparing the two.
++		 */
++		events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
++		events_got = seq - ctx->cq_last_tm_flush;
++		if (events_got < events_needed)
++			break;
++
++		io_kill_timeout(req, 0);
++	}
++	ctx->cq_last_tm_flush = seq;
++	spin_unlock_irq(&ctx->timeout_lock);
++}
++
++static void __io_commit_cqring_flush(struct io_ring_ctx *ctx)
++{
++	if (ctx->off_timeout_used)
++		io_flush_timeouts(ctx);
++	if (ctx->drain_active)
++		io_queue_deferred(ctx);
++}
++
++static inline void io_commit_cqring(struct io_ring_ctx *ctx)
++{
++	if (unlikely(ctx->off_timeout_used || ctx->drain_active))
++		__io_commit_cqring_flush(ctx);
++	/* order cqe stores with ring update */
++	smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
++}
++
++static inline bool io_sqring_full(struct io_ring_ctx *ctx)
++{
++	struct io_rings *r = ctx->rings;
++
++	return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
++}
++
++static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
++{
++	return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
++}
++
++static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx)
++{
++	struct io_rings *rings = ctx->rings;
++	unsigned tail, mask = ctx->cq_entries - 1;
++
++	/*
++	 * writes to the cq entry need to come after reading head; the
++	 * control dependency is enough as we're using WRITE_ONCE to
++	 * fill the cq entry
++	 */
++	if (__io_cqring_events(ctx) == ctx->cq_entries)
++		return NULL;
++
++	tail = ctx->cached_cq_tail++;
++	return &rings->cqes[tail & mask];
++}
++
++static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
++{
++	if (likely(!ctx->cq_ev_fd))
++		return false;
++	if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
++		return false;
++	return !ctx->eventfd_async || io_wq_current_is_worker();
++}
++
++/*
++ * This should only get called when at least one event has been posted.
++ * Some applications rely on the eventfd notification count only changing
++ * IFF a new CQE has been added to the CQ ring. There's no depedency on
++ * 1:1 relationship between how many times this function is called (and
++ * hence the eventfd count) and number of CQEs posted to the CQ ring.
++ */
++static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
++{
++	/*
++	 * wake_up_all() may seem excessive, but io_wake_function() and
++	 * io_should_wake() handle the termination of the loop and only
++	 * wake as many waiters as we need to.
++	 */
++	if (wq_has_sleeper(&ctx->cq_wait))
++		wake_up_all(&ctx->cq_wait);
++	if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
++		wake_up(&ctx->sq_data->wait);
++	if (io_should_trigger_evfd(ctx))
++		eventfd_signal(ctx->cq_ev_fd, 1);
++	if (waitqueue_active(&ctx->poll_wait))
++		wake_up_interruptible(&ctx->poll_wait);
++}
++
++static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
++{
++	/* see waitqueue_active() comment */
++	smp_mb();
++
++	if (ctx->flags & IORING_SETUP_SQPOLL) {
++		if (waitqueue_active(&ctx->cq_wait))
++			wake_up_all(&ctx->cq_wait);
++	}
++	if (io_should_trigger_evfd(ctx))
++		eventfd_signal(ctx->cq_ev_fd, 1);
++	if (waitqueue_active(&ctx->poll_wait))
++		wake_up_interruptible(&ctx->poll_wait);
++}
++
++/* Returns true if there are no backlogged entries after the flush */
++static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
++{
++	bool all_flushed, posted;
++
++	if (!force && __io_cqring_events(ctx) == ctx->cq_entries)
++		return false;
++
++	posted = false;
++	spin_lock(&ctx->completion_lock);
++	while (!list_empty(&ctx->cq_overflow_list)) {
++		struct io_uring_cqe *cqe = io_get_cqe(ctx);
++		struct io_overflow_cqe *ocqe;
++
++		if (!cqe && !force)
++			break;
++		ocqe = list_first_entry(&ctx->cq_overflow_list,
++					struct io_overflow_cqe, list);
++		if (cqe)
++			memcpy(cqe, &ocqe->cqe, sizeof(*cqe));
++		else
++			io_account_cq_overflow(ctx);
++
++		posted = true;
++		list_del(&ocqe->list);
++		kfree(ocqe);
++	}
++
++	all_flushed = list_empty(&ctx->cq_overflow_list);
++	if (all_flushed) {
++		clear_bit(0, &ctx->check_cq_overflow);
++		WRITE_ONCE(ctx->rings->sq_flags,
++			   ctx->rings->sq_flags & ~IORING_SQ_CQ_OVERFLOW);
++	}
++
++	if (posted)
++		io_commit_cqring(ctx);
++	spin_unlock(&ctx->completion_lock);
++	if (posted)
++		io_cqring_ev_posted(ctx);
++	return all_flushed;
++}
++
++static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx)
++{
++	bool ret = true;
++
++	if (test_bit(0, &ctx->check_cq_overflow)) {
++		/* iopoll syncs against uring_lock, not completion_lock */
++		if (ctx->flags & IORING_SETUP_IOPOLL)
++			mutex_lock(&ctx->uring_lock);
++		ret = __io_cqring_overflow_flush(ctx, false);
++		if (ctx->flags & IORING_SETUP_IOPOLL)
++			mutex_unlock(&ctx->uring_lock);
++	}
++
++	return ret;
++}
++
++/* must to be called somewhat shortly after putting a request */
++static inline void io_put_task(struct task_struct *task, int nr)
++{
++	struct io_uring_task *tctx = task->io_uring;
++
++	if (likely(task == current)) {
++		tctx->cached_refs += nr;
++	} else {
++		percpu_counter_sub(&tctx->inflight, nr);
++		if (unlikely(atomic_read(&tctx->in_idle)))
++			wake_up(&tctx->wait);
++		put_task_struct_many(task, nr);
++	}
++}
++
++static void io_task_refs_refill(struct io_uring_task *tctx)
++{
++	unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR;
++
++	percpu_counter_add(&tctx->inflight, refill);
++	refcount_add(refill, &current->usage);
++	tctx->cached_refs += refill;
++}
++
++static inline void io_get_task_refs(int nr)
++{
++	struct io_uring_task *tctx = current->io_uring;
++
++	tctx->cached_refs -= nr;
++	if (unlikely(tctx->cached_refs < 0))
++		io_task_refs_refill(tctx);
++}
++
++static __cold void io_uring_drop_tctx_refs(struct task_struct *task)
++{
++	struct io_uring_task *tctx = task->io_uring;
++	unsigned int refs = tctx->cached_refs;
++
++	if (refs) {
++		tctx->cached_refs = 0;
++		percpu_counter_sub(&tctx->inflight, refs);
++		put_task_struct_many(task, refs);
++	}
++}
++
++static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data,
++				     s32 res, u32 cflags)
++{
++	struct io_overflow_cqe *ocqe;
++
++	ocqe = kmalloc(sizeof(*ocqe), GFP_ATOMIC | __GFP_ACCOUNT);
++	if (!ocqe) {
++		/*
++		 * If we're in ring overflow flush mode, or in task cancel mode,
++		 * or cannot allocate an overflow entry, then we need to drop it
++		 * on the floor.
++		 */
++		io_account_cq_overflow(ctx);
++		return false;
++	}
++	if (list_empty(&ctx->cq_overflow_list)) {
++		set_bit(0, &ctx->check_cq_overflow);
++		WRITE_ONCE(ctx->rings->sq_flags,
++			   ctx->rings->sq_flags | IORING_SQ_CQ_OVERFLOW);
++
++	}
++	ocqe->cqe.user_data = user_data;
++	ocqe->cqe.res = res;
++	ocqe->cqe.flags = cflags;
++	list_add_tail(&ocqe->list, &ctx->cq_overflow_list);
++	return true;
++}
++
++static inline bool __io_fill_cqe(struct io_ring_ctx *ctx, u64 user_data,
++				 s32 res, u32 cflags)
++{
++	struct io_uring_cqe *cqe;
++
++	trace_io_uring_complete(ctx, user_data, res, cflags);
++
++	/*
++	 * If we can't get a cq entry, userspace overflowed the
++	 * submission (by quite a lot). Increment the overflow count in
++	 * the ring.
++	 */
++	cqe = io_get_cqe(ctx);
++	if (likely(cqe)) {
++		WRITE_ONCE(cqe->user_data, user_data);
++		WRITE_ONCE(cqe->res, res);
++		WRITE_ONCE(cqe->flags, cflags);
++		return true;
++	}
++	return io_cqring_event_overflow(ctx, user_data, res, cflags);
++}
++
++static noinline void io_fill_cqe_req(struct io_kiocb *req, s32 res, u32 cflags)
++{
++	__io_fill_cqe(req->ctx, req->user_data, res, cflags);
++}
++
++static noinline bool io_fill_cqe_aux(struct io_ring_ctx *ctx, u64 user_data,
++				     s32 res, u32 cflags)
++{
++	ctx->cq_extra++;
++	return __io_fill_cqe(ctx, user_data, res, cflags);
++}
++
++static void io_req_complete_post(struct io_kiocb *req, s32 res,
++				 u32 cflags)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	spin_lock(&ctx->completion_lock);
++	__io_fill_cqe(ctx, req->user_data, res, cflags);
++	/*
++	 * If we're the last reference to this request, add to our locked
++	 * free_list cache.
++	 */
++	if (req_ref_put_and_test(req)) {
++		if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
++			if (req->flags & IO_DISARM_MASK)
++				io_disarm_next(req);
++			if (req->link) {
++				io_req_task_queue(req->link);
++				req->link = NULL;
++			}
++		}
++		io_dismantle_req(req);
++		io_put_task(req->task, 1);
++		list_add(&req->inflight_entry, &ctx->locked_free_list);
++		ctx->locked_free_nr++;
++	} else {
++		if (!percpu_ref_tryget(&ctx->refs))
++			req = NULL;
++	}
++	io_commit_cqring(ctx);
++	spin_unlock(&ctx->completion_lock);
++
++	if (req) {
++		io_cqring_ev_posted(ctx);
++		percpu_ref_put(&ctx->refs);
++	}
++}
++
++static inline bool io_req_needs_clean(struct io_kiocb *req)
++{
++	return req->flags & IO_REQ_CLEAN_FLAGS;
++}
++
++static inline void io_req_complete_state(struct io_kiocb *req, s32 res,
++					 u32 cflags)
++{
++	if (io_req_needs_clean(req))
++		io_clean_op(req);
++	req->result = res;
++	req->compl.cflags = cflags;
++	req->flags |= REQ_F_COMPLETE_INLINE;
++}
++
++static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
++				     s32 res, u32 cflags)
++{
++	if (issue_flags & IO_URING_F_COMPLETE_DEFER)
++		io_req_complete_state(req, res, cflags);
++	else
++		io_req_complete_post(req, res, cflags);
++}
++
++static inline void io_req_complete(struct io_kiocb *req, s32 res)
++{
++	__io_req_complete(req, 0, res, 0);
++}
++
++static void io_req_complete_failed(struct io_kiocb *req, s32 res)
++{
++	req_set_fail(req);
++	io_req_complete_post(req, res, 0);
++}
++
++static void io_req_complete_fail_submit(struct io_kiocb *req)
++{
++	/*
++	 * We don't submit, fail them all, for that replace hardlinks with
++	 * normal links. Extra REQ_F_LINK is tolerated.
++	 */
++	req->flags &= ~REQ_F_HARDLINK;
++	req->flags |= REQ_F_LINK;
++	io_req_complete_failed(req, req->result);
++}
++
++/*
++ * Don't initialise the fields below on every allocation, but do that in
++ * advance and keep them valid across allocations.
++ */
++static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx)
++{
++	req->ctx = ctx;
++	req->link = NULL;
++	req->async_data = NULL;
++	/* not necessary, but safer to zero */
++	req->result = 0;
++}
++
++static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx,
++					struct io_submit_state *state)
++{
++	spin_lock(&ctx->completion_lock);
++	list_splice_init(&ctx->locked_free_list, &state->free_list);
++	ctx->locked_free_nr = 0;
++	spin_unlock(&ctx->completion_lock);
++}
++
++/* Returns true IFF there are requests in the cache */
++static bool io_flush_cached_reqs(struct io_ring_ctx *ctx)
++{
++	struct io_submit_state *state = &ctx->submit_state;
++	int nr;
++
++	/*
++	 * If we have more than a batch's worth of requests in our IRQ side
++	 * locked cache, grab the lock and move them over to our submission
++	 * side cache.
++	 */
++	if (READ_ONCE(ctx->locked_free_nr) > IO_COMPL_BATCH)
++		io_flush_cached_locked_reqs(ctx, state);
++
++	nr = state->free_reqs;
++	while (!list_empty(&state->free_list)) {
++		struct io_kiocb *req = list_first_entry(&state->free_list,
++					struct io_kiocb, inflight_entry);
++
++		list_del(&req->inflight_entry);
++		state->reqs[nr++] = req;
++		if (nr == ARRAY_SIZE(state->reqs))
++			break;
++	}
++
++	state->free_reqs = nr;
++	return nr != 0;
++}
++
++/*
++ * A request might get retired back into the request caches even before opcode
++ * handlers and io_issue_sqe() are done with it, e.g. inline completion path.
++ * Because of that, io_alloc_req() should be called only under ->uring_lock
++ * and with extra caution to not get a request that is still worked on.
++ */
++static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
++	__must_hold(&ctx->uring_lock)
++{
++	struct io_submit_state *state = &ctx->submit_state;
++	gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
++	int ret, i;
++
++	BUILD_BUG_ON(ARRAY_SIZE(state->reqs) < IO_REQ_ALLOC_BATCH);
++
++	if (likely(state->free_reqs || io_flush_cached_reqs(ctx)))
++		goto got_req;
++
++	ret = kmem_cache_alloc_bulk(req_cachep, gfp, IO_REQ_ALLOC_BATCH,
++				    state->reqs);
++
++	/*
++	 * Bulk alloc is all-or-nothing. If we fail to get a batch,
++	 * retry single alloc to be on the safe side.
++	 */
++	if (unlikely(ret <= 0)) {
++		state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
++		if (!state->reqs[0])
++			return NULL;
++		ret = 1;
++	}
++
++	for (i = 0; i < ret; i++)
++		io_preinit_req(state->reqs[i], ctx);
++	state->free_reqs = ret;
++got_req:
++	state->free_reqs--;
++	return state->reqs[state->free_reqs];
++}
++
++static inline void io_put_file(struct file *file)
++{
++	if (file)
++		fput(file);
++}
++
++static void io_dismantle_req(struct io_kiocb *req)
++{
++	unsigned int flags = req->flags;
++
++	if (io_req_needs_clean(req))
++		io_clean_op(req);
++	if (!(flags & REQ_F_FIXED_FILE))
++		io_put_file(req->file);
++	if (req->fixed_rsrc_refs)
++		percpu_ref_put(req->fixed_rsrc_refs);
++	if (req->async_data) {
++		kfree(req->async_data);
++		req->async_data = NULL;
++	}
++}
++
++static void __io_free_req(struct io_kiocb *req)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	io_dismantle_req(req);
++	io_put_task(req->task, 1);
++
++	spin_lock(&ctx->completion_lock);
++	list_add(&req->inflight_entry, &ctx->locked_free_list);
++	ctx->locked_free_nr++;
++	spin_unlock(&ctx->completion_lock);
++
++	percpu_ref_put(&ctx->refs);
++}
++
++static inline void io_remove_next_linked(struct io_kiocb *req)
++{
++	struct io_kiocb *nxt = req->link;
++
++	req->link = nxt->link;
++	nxt->link = NULL;
++}
++
++static bool io_kill_linked_timeout(struct io_kiocb *req)
++	__must_hold(&req->ctx->completion_lock)
++	__must_hold(&req->ctx->timeout_lock)
++{
++	struct io_kiocb *link = req->link;
++
++	if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
++		struct io_timeout_data *io = link->async_data;
++
++		io_remove_next_linked(req);
++		link->timeout.head = NULL;
++		if (hrtimer_try_to_cancel(&io->timer) != -1) {
++			list_del(&link->timeout.list);
++			io_fill_cqe_req(link, -ECANCELED, 0);
++			io_put_req_deferred(link);
++			return true;
++		}
++	}
++	return false;
++}
++
++static void io_fail_links(struct io_kiocb *req)
++	__must_hold(&req->ctx->completion_lock)
++{
++	struct io_kiocb *nxt, *link = req->link;
++
++	req->link = NULL;
++	while (link) {
++		long res = -ECANCELED;
++
++		if (link->flags & REQ_F_FAIL)
++			res = link->result;
++
++		nxt = link->link;
++		link->link = NULL;
++
++		trace_io_uring_fail_link(req, link);
++		io_fill_cqe_req(link, res, 0);
++		io_put_req_deferred(link);
++		link = nxt;
++	}
++}
++
++static bool io_disarm_next(struct io_kiocb *req)
++	__must_hold(&req->ctx->completion_lock)
++{
++	bool posted = false;
++
++	if (req->flags & REQ_F_ARM_LTIMEOUT) {
++		struct io_kiocb *link = req->link;
++
++		req->flags &= ~REQ_F_ARM_LTIMEOUT;
++		if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
++			io_remove_next_linked(req);
++			io_fill_cqe_req(link, -ECANCELED, 0);
++			io_put_req_deferred(link);
++			posted = true;
++		}
++	} else if (req->flags & REQ_F_LINK_TIMEOUT) {
++		struct io_ring_ctx *ctx = req->ctx;
++
++		spin_lock_irq(&ctx->timeout_lock);
++		posted = io_kill_linked_timeout(req);
++		spin_unlock_irq(&ctx->timeout_lock);
++	}
++	if (unlikely((req->flags & REQ_F_FAIL) &&
++		     !(req->flags & REQ_F_HARDLINK))) {
++		posted |= (req->link != NULL);
++		io_fail_links(req);
++	}
++	return posted;
++}
++
++static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
++{
++	struct io_kiocb *nxt;
++
++	/*
++	 * If LINK is set, we have dependent requests in this chain. If we
++	 * didn't fail this request, queue the first one up, moving any other
++	 * dependencies to the next request. In case of failure, fail the rest
++	 * of the chain.
++	 */
++	if (req->flags & IO_DISARM_MASK) {
++		struct io_ring_ctx *ctx = req->ctx;
++		bool posted;
++
++		spin_lock(&ctx->completion_lock);
++		posted = io_disarm_next(req);
++		if (posted)
++			io_commit_cqring(req->ctx);
++		spin_unlock(&ctx->completion_lock);
++		if (posted)
++			io_cqring_ev_posted(ctx);
++	}
++	nxt = req->link;
++	req->link = NULL;
++	return nxt;
++}
++
++static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
++{
++	if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK))))
++		return NULL;
++	return __io_req_find_next(req);
++}
++
++static void ctx_flush_and_put(struct io_ring_ctx *ctx, bool *locked)
++{
++	if (!ctx)
++		return;
++	if (*locked) {
++		if (ctx->submit_state.compl_nr)
++			io_submit_flush_completions(ctx);
++		mutex_unlock(&ctx->uring_lock);
++		*locked = false;
++	}
++	percpu_ref_put(&ctx->refs);
++}
++
++static void tctx_task_work(struct callback_head *cb)
++{
++	bool locked = false;
++	struct io_ring_ctx *ctx = NULL;
++	struct io_uring_task *tctx = container_of(cb, struct io_uring_task,
++						  task_work);
++
++	while (1) {
++		struct io_wq_work_node *node;
++
++		if (!tctx->task_list.first && locked && ctx->submit_state.compl_nr)
++			io_submit_flush_completions(ctx);
++
++		spin_lock_irq(&tctx->task_lock);
++		node = tctx->task_list.first;
++		INIT_WQ_LIST(&tctx->task_list);
++		if (!node)
++			tctx->task_running = false;
++		spin_unlock_irq(&tctx->task_lock);
++		if (!node)
++			break;
++
++		do {
++			struct io_wq_work_node *next = node->next;
++			struct io_kiocb *req = container_of(node, struct io_kiocb,
++							    io_task_work.node);
++
++			if (req->ctx != ctx) {
++				ctx_flush_and_put(ctx, &locked);
++				ctx = req->ctx;
++				/* if not contended, grab and improve batching */
++				locked = mutex_trylock(&ctx->uring_lock);
++				percpu_ref_get(&ctx->refs);
++			}
++			req->io_task_work.func(req, &locked);
++			node = next;
++		} while (node);
++
++		cond_resched();
++	}
++
++	ctx_flush_and_put(ctx, &locked);
++
++	/* relaxed read is enough as only the task itself sets ->in_idle */
++	if (unlikely(atomic_read(&tctx->in_idle)))
++		io_uring_drop_tctx_refs(current);
++}
++
++static void io_req_task_work_add(struct io_kiocb *req)
++{
++	struct task_struct *tsk = req->task;
++	struct io_uring_task *tctx = tsk->io_uring;
++	enum task_work_notify_mode notify;
++	struct io_wq_work_node *node;
++	unsigned long flags;
++	bool running;
++
++	WARN_ON_ONCE(!tctx);
++
++	spin_lock_irqsave(&tctx->task_lock, flags);
++	wq_list_add_tail(&req->io_task_work.node, &tctx->task_list);
++	running = tctx->task_running;
++	if (!running)
++		tctx->task_running = true;
++	spin_unlock_irqrestore(&tctx->task_lock, flags);
++
++	/* task_work already pending, we're done */
++	if (running)
++		return;
++
++	/*
++	 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
++	 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
++	 * processing task_work. There's no reliable way to tell if TWA_RESUME
++	 * will do the job.
++	 */
++	notify = (req->ctx->flags & IORING_SETUP_SQPOLL) ? TWA_NONE : TWA_SIGNAL;
++	if (!task_work_add(tsk, &tctx->task_work, notify)) {
++		wake_up_process(tsk);
++		return;
++	}
++
++	spin_lock_irqsave(&tctx->task_lock, flags);
++	tctx->task_running = false;
++	node = tctx->task_list.first;
++	INIT_WQ_LIST(&tctx->task_list);
++	spin_unlock_irqrestore(&tctx->task_lock, flags);
++
++	while (node) {
++		req = container_of(node, struct io_kiocb, io_task_work.node);
++		node = node->next;
++		if (llist_add(&req->io_task_work.fallback_node,
++			      &req->ctx->fallback_llist))
++			schedule_delayed_work(&req->ctx->fallback_work, 1);
++	}
++}
++
++static void io_req_task_cancel(struct io_kiocb *req, bool *locked)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	/* not needed for normal modes, but SQPOLL depends on it */
++	io_tw_lock(ctx, locked);
++	io_req_complete_failed(req, req->result);
++}
++
++static void io_req_task_submit(struct io_kiocb *req, bool *locked)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	io_tw_lock(ctx, locked);
++	/* req->task == current here, checking PF_EXITING is safe */
++	if (likely(!(req->task->flags & PF_EXITING)))
++		__io_queue_sqe(req);
++	else
++		io_req_complete_failed(req, -EFAULT);
++}
++
++static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
++{
++	req->result = ret;
++	req->io_task_work.func = io_req_task_cancel;
++	io_req_task_work_add(req);
++}
++
++static void io_req_task_queue(struct io_kiocb *req)
++{
++	req->io_task_work.func = io_req_task_submit;
++	io_req_task_work_add(req);
++}
++
++static void io_req_task_queue_reissue(struct io_kiocb *req)
++{
++	req->io_task_work.func = io_queue_async_work;
++	io_req_task_work_add(req);
++}
++
++static inline void io_queue_next(struct io_kiocb *req)
++{
++	struct io_kiocb *nxt = io_req_find_next(req);
++
++	if (nxt)
++		io_req_task_queue(nxt);
++}
++
++static void io_free_req(struct io_kiocb *req)
++{
++	io_queue_next(req);
++	__io_free_req(req);
++}
++
++static void io_free_req_work(struct io_kiocb *req, bool *locked)
++{
++	io_free_req(req);
++}
++
++struct req_batch {
++	struct task_struct	*task;
++	int			task_refs;
++	int			ctx_refs;
++};
++
++static inline void io_init_req_batch(struct req_batch *rb)
++{
++	rb->task_refs = 0;
++	rb->ctx_refs = 0;
++	rb->task = NULL;
++}
++
++static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
++				     struct req_batch *rb)
++{
++	if (rb->ctx_refs)
++		percpu_ref_put_many(&ctx->refs, rb->ctx_refs);
++	if (rb->task)
++		io_put_task(rb->task, rb->task_refs);
++}
++
++static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req,
++			      struct io_submit_state *state)
++{
++	io_queue_next(req);
++	io_dismantle_req(req);
++
++	if (req->task != rb->task) {
++		if (rb->task)
++			io_put_task(rb->task, rb->task_refs);
++		rb->task = req->task;
++		rb->task_refs = 0;
++	}
++	rb->task_refs++;
++	rb->ctx_refs++;
++
++	if (state->free_reqs != ARRAY_SIZE(state->reqs))
++		state->reqs[state->free_reqs++] = req;
++	else
++		list_add(&req->inflight_entry, &state->free_list);
++}
++
++static void io_submit_flush_completions(struct io_ring_ctx *ctx)
++	__must_hold(&ctx->uring_lock)
++{
++	struct io_submit_state *state = &ctx->submit_state;
++	int i, nr = state->compl_nr;
++	struct req_batch rb;
++
++	spin_lock(&ctx->completion_lock);
++	for (i = 0; i < nr; i++) {
++		struct io_kiocb *req = state->compl_reqs[i];
++
++		__io_fill_cqe(ctx, req->user_data, req->result,
++			      req->compl.cflags);
++	}
++	io_commit_cqring(ctx);
++	spin_unlock(&ctx->completion_lock);
++	io_cqring_ev_posted(ctx);
++
++	io_init_req_batch(&rb);
++	for (i = 0; i < nr; i++) {
++		struct io_kiocb *req = state->compl_reqs[i];
++
++		if (req_ref_put_and_test(req))
++			io_req_free_batch(&rb, req, &ctx->submit_state);
++	}
++
++	io_req_free_batch_finish(ctx, &rb);
++	state->compl_nr = 0;
++}
++
++/*
++ * Drop reference to request, return next in chain (if there is one) if this
++ * was the last reference to this request.
++ */
++static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
++{
++	struct io_kiocb *nxt = NULL;
++
++	if (req_ref_put_and_test(req)) {
++		nxt = io_req_find_next(req);
++		__io_free_req(req);
++	}
++	return nxt;
++}
++
++static inline void io_put_req(struct io_kiocb *req)
++{
++	if (req_ref_put_and_test(req))
++		io_free_req(req);
++}
++
++static inline void io_put_req_deferred(struct io_kiocb *req)
++{
++	if (req_ref_put_and_test(req)) {
++		req->io_task_work.func = io_free_req_work;
++		io_req_task_work_add(req);
++	}
++}
++
++static unsigned io_cqring_events(struct io_ring_ctx *ctx)
++{
++	/* See comment at the top of this file */
++	smp_rmb();
++	return __io_cqring_events(ctx);
++}
++
++static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
++{
++	struct io_rings *rings = ctx->rings;
++
++	/* make sure SQ entry isn't read before tail */
++	return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
++}
++
++static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
++{
++	unsigned int cflags;
++
++	cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
++	cflags |= IORING_CQE_F_BUFFER;
++	req->flags &= ~REQ_F_BUFFER_SELECTED;
++	kfree(kbuf);
++	return cflags;
++}
++
++static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
++{
++	struct io_buffer *kbuf;
++
++	if (likely(!(req->flags & REQ_F_BUFFER_SELECTED)))
++		return 0;
++	kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
++	return io_put_kbuf(req, kbuf);
++}
++
++static inline bool io_run_task_work(void)
++{
++	if (test_thread_flag(TIF_NOTIFY_SIGNAL) || current->task_works) {
++		__set_current_state(TASK_RUNNING);
++		tracehook_notify_signal();
++		return true;
++	}
++
++	return false;
++}
++
++/*
++ * Find and free completed poll iocbs
++ */
++static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
++			       struct list_head *done)
++{
++	struct req_batch rb;
++	struct io_kiocb *req;
++
++	/* order with ->result store in io_complete_rw_iopoll() */
++	smp_rmb();
++
++	io_init_req_batch(&rb);
++	while (!list_empty(done)) {
++		req = list_first_entry(done, struct io_kiocb, inflight_entry);
++		list_del(&req->inflight_entry);
++
++		io_fill_cqe_req(req, req->result, io_put_rw_kbuf(req));
++		(*nr_events)++;
++
++		if (req_ref_put_and_test(req))
++			io_req_free_batch(&rb, req, &ctx->submit_state);
++	}
++
++	io_commit_cqring(ctx);
++	io_cqring_ev_posted_iopoll(ctx);
++	io_req_free_batch_finish(ctx, &rb);
++}
++
++static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
++			long min)
++{
++	struct io_kiocb *req, *tmp;
++	LIST_HEAD(done);
++	bool spin;
++
++	/*
++	 * Only spin for completions if we don't have multiple devices hanging
++	 * off our complete list, and we're under the requested amount.
++	 */
++	spin = !ctx->poll_multi_queue && *nr_events < min;
++
++	list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
++		struct kiocb *kiocb = &req->rw.kiocb;
++		int ret;
++
++		/*
++		 * Move completed and retryable entries to our local lists.
++		 * If we find a request that requires polling, break out
++		 * and complete those lists first, if we have entries there.
++		 */
++		if (READ_ONCE(req->iopoll_completed)) {
++			list_move_tail(&req->inflight_entry, &done);
++			continue;
++		}
++		if (!list_empty(&done))
++			break;
++
++		ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin);
++		if (unlikely(ret < 0))
++			return ret;
++		else if (ret)
++			spin = false;
++
++		/* iopoll may have completed current req */
++		if (READ_ONCE(req->iopoll_completed))
++			list_move_tail(&req->inflight_entry, &done);
++	}
++
++	if (!list_empty(&done))
++		io_iopoll_complete(ctx, nr_events, &done);
++
++	return 0;
++}
++
++/*
++ * We can't just wait for polled events to come to us, we have to actively
++ * find and complete them.
++ */
++static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
++{
++	if (!(ctx->flags & IORING_SETUP_IOPOLL))
++		return;
++
++	mutex_lock(&ctx->uring_lock);
++	while (!list_empty(&ctx->iopoll_list)) {
++		unsigned int nr_events = 0;
++
++		io_do_iopoll(ctx, &nr_events, 0);
++
++		/* let it sleep and repeat later if can't complete a request */
++		if (nr_events == 0)
++			break;
++		/*
++		 * Ensure we allow local-to-the-cpu processing to take place,
++		 * in this case we need to ensure that we reap all events.
++		 * Also let task_work, etc. to progress by releasing the mutex
++		 */
++		if (need_resched()) {
++			mutex_unlock(&ctx->uring_lock);
++			cond_resched();
++			mutex_lock(&ctx->uring_lock);
++		}
++	}
++	mutex_unlock(&ctx->uring_lock);
++}
++
++static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
++{
++	unsigned int nr_events = 0;
++	int ret = 0;
++
++	/*
++	 * We disallow the app entering submit/complete with polling, but we
++	 * still need to lock the ring to prevent racing with polled issue
++	 * that got punted to a workqueue.
++	 */
++	mutex_lock(&ctx->uring_lock);
++	/*
++	 * Don't enter poll loop if we already have events pending.
++	 * If we do, we can potentially be spinning for commands that
++	 * already triggered a CQE (eg in error).
++	 */
++	if (test_bit(0, &ctx->check_cq_overflow))
++		__io_cqring_overflow_flush(ctx, false);
++	if (io_cqring_events(ctx))
++		goto out;
++	do {
++		/*
++		 * If a submit got punted to a workqueue, we can have the
++		 * application entering polling for a command before it gets
++		 * issued. That app will hold the uring_lock for the duration
++		 * of the poll right here, so we need to take a breather every
++		 * now and then to ensure that the issue has a chance to add
++		 * the poll to the issued list. Otherwise we can spin here
++		 * forever, while the workqueue is stuck trying to acquire the
++		 * very same mutex.
++		 */
++		if (list_empty(&ctx->iopoll_list)) {
++			u32 tail = ctx->cached_cq_tail;
++
++			mutex_unlock(&ctx->uring_lock);
++			io_run_task_work();
++			mutex_lock(&ctx->uring_lock);
++
++			/* some requests don't go through iopoll_list */
++			if (tail != ctx->cached_cq_tail ||
++			    list_empty(&ctx->iopoll_list))
++				break;
++		}
++		ret = io_do_iopoll(ctx, &nr_events, min);
++	} while (!ret && nr_events < min && !need_resched());
++out:
++	mutex_unlock(&ctx->uring_lock);
++	return ret;
++}
++
++static void kiocb_end_write(struct io_kiocb *req)
++{
++	/*
++	 * Tell lockdep we inherited freeze protection from submission
++	 * thread.
++	 */
++	if (req->flags & REQ_F_ISREG) {
++		struct super_block *sb = file_inode(req->file)->i_sb;
++
++		__sb_writers_acquired(sb, SB_FREEZE_WRITE);
++		sb_end_write(sb);
++	}
++}
++
++#ifdef CONFIG_BLOCK
++static bool io_resubmit_prep(struct io_kiocb *req)
++{
++	struct io_async_rw *rw = req->async_data;
++
++	if (!rw)
++		return !io_req_prep_async(req);
++	iov_iter_restore(&rw->iter, &rw->iter_state);
++	return true;
++}
++
++static bool io_rw_should_reissue(struct io_kiocb *req)
++{
++	umode_t mode = file_inode(req->file)->i_mode;
++	struct io_ring_ctx *ctx = req->ctx;
++
++	if (!S_ISBLK(mode) && !S_ISREG(mode))
++		return false;
++	if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
++	    !(ctx->flags & IORING_SETUP_IOPOLL)))
++		return false;
++	/*
++	 * If ref is dying, we might be running poll reap from the exit work.
++	 * Don't attempt to reissue from that path, just let it fail with
++	 * -EAGAIN.
++	 */
++	if (percpu_ref_is_dying(&ctx->refs))
++		return false;
++	/*
++	 * Play it safe and assume not safe to re-import and reissue if we're
++	 * not in the original thread group (or in task context).
++	 */
++	if (!same_thread_group(req->task, current) || !in_task())
++		return false;
++	return true;
++}
++#else
++static bool io_resubmit_prep(struct io_kiocb *req)
++{
++	return false;
++}
++static bool io_rw_should_reissue(struct io_kiocb *req)
++{
++	return false;
++}
++#endif
++
++static bool __io_complete_rw_common(struct io_kiocb *req, long res)
++{
++	if (req->rw.kiocb.ki_flags & IOCB_WRITE) {
++		kiocb_end_write(req);
++		fsnotify_modify(req->file);
++	} else {
++		fsnotify_access(req->file);
++	}
++	if (res != req->result) {
++		if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
++		    io_rw_should_reissue(req)) {
++			req->flags |= REQ_F_REISSUE;
++			return true;
++		}
++		req_set_fail(req);
++		req->result = res;
++	}
++	return false;
++}
++
++static inline int io_fixup_rw_res(struct io_kiocb *req, unsigned res)
++{
++	struct io_async_rw *io = req->async_data;
++
++	/* add previously done IO, if any */
++	if (io && io->bytes_done > 0) {
++		if (res < 0)
++			res = io->bytes_done;
++		else
++			res += io->bytes_done;
++	}
++	return res;
++}
++
++static void io_req_task_complete(struct io_kiocb *req, bool *locked)
++{
++	unsigned int cflags = io_put_rw_kbuf(req);
++	int res = req->result;
++
++	if (*locked) {
++		struct io_ring_ctx *ctx = req->ctx;
++		struct io_submit_state *state = &ctx->submit_state;
++
++		io_req_complete_state(req, res, cflags);
++		state->compl_reqs[state->compl_nr++] = req;
++		if (state->compl_nr == ARRAY_SIZE(state->compl_reqs))
++			io_submit_flush_completions(ctx);
++	} else {
++		io_req_complete_post(req, res, cflags);
++	}
++}
++
++static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
++			     unsigned int issue_flags)
++{
++	if (__io_complete_rw_common(req, res))
++		return;
++	__io_req_complete(req, issue_flags, io_fixup_rw_res(req, res), io_put_rw_kbuf(req));
++}
++
++static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
++{
++	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
++
++	if (__io_complete_rw_common(req, res))
++		return;
++	req->result = io_fixup_rw_res(req, res);
++	req->io_task_work.func = io_req_task_complete;
++	io_req_task_work_add(req);
++}
++
++static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
++{
++	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
++
++	if (kiocb->ki_flags & IOCB_WRITE)
++		kiocb_end_write(req);
++	if (unlikely(res != req->result)) {
++		if (res == -EAGAIN && io_rw_should_reissue(req)) {
++			req->flags |= REQ_F_REISSUE;
++			return;
++		}
++	}
++
++	WRITE_ONCE(req->result, res);
++	/* order with io_iopoll_complete() checking ->result */
++	smp_wmb();
++	WRITE_ONCE(req->iopoll_completed, 1);
++}
++
++/*
++ * After the iocb has been issued, it's safe to be found on the poll list.
++ * Adding the kiocb to the list AFTER submission ensures that we don't
++ * find it from a io_do_iopoll() thread before the issuer is done
++ * accessing the kiocb cookie.
++ */
++static void io_iopoll_req_issued(struct io_kiocb *req)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	const bool in_async = io_wq_current_is_worker();
++
++	/* workqueue context doesn't hold uring_lock, grab it now */
++	if (unlikely(in_async))
++		mutex_lock(&ctx->uring_lock);
++
++	/*
++	 * Track whether we have multiple files in our lists. This will impact
++	 * how we do polling eventually, not spinning if we're on potentially
++	 * different devices.
++	 */
++	if (list_empty(&ctx->iopoll_list)) {
++		ctx->poll_multi_queue = false;
++	} else if (!ctx->poll_multi_queue) {
++		struct io_kiocb *list_req;
++		unsigned int queue_num0, queue_num1;
++
++		list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
++						inflight_entry);
++
++		if (list_req->file != req->file) {
++			ctx->poll_multi_queue = true;
++		} else {
++			queue_num0 = blk_qc_t_to_queue_num(list_req->rw.kiocb.ki_cookie);
++			queue_num1 = blk_qc_t_to_queue_num(req->rw.kiocb.ki_cookie);
++			if (queue_num0 != queue_num1)
++				ctx->poll_multi_queue = true;
++		}
++	}
++
++	/*
++	 * For fast devices, IO may have already completed. If it has, add
++	 * it to the front so we find it first.
++	 */
++	if (READ_ONCE(req->iopoll_completed))
++		list_add(&req->inflight_entry, &ctx->iopoll_list);
++	else
++		list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
++
++	if (unlikely(in_async)) {
++		/*
++		 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
++		 * in sq thread task context or in io worker task context. If
++		 * current task context is sq thread, we don't need to check
++		 * whether should wake up sq thread.
++		 */
++		if ((ctx->flags & IORING_SETUP_SQPOLL) &&
++		    wq_has_sleeper(&ctx->sq_data->wait))
++			wake_up(&ctx->sq_data->wait);
++
++		mutex_unlock(&ctx->uring_lock);
++	}
++}
++
++static bool io_bdev_nowait(struct block_device *bdev)
++{
++	return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
++}
++
++/*
++ * If we tracked the file through the SCM inflight mechanism, we could support
++ * any file. For now, just ensure that anything potentially problematic is done
++ * inline.
++ */
++static bool __io_file_supports_nowait(struct file *file, int rw)
++{
++	umode_t mode = file_inode(file)->i_mode;
++
++	if (S_ISBLK(mode)) {
++		if (IS_ENABLED(CONFIG_BLOCK) &&
++		    io_bdev_nowait(I_BDEV(file->f_mapping->host)))
++			return true;
++		return false;
++	}
++	if (S_ISSOCK(mode))
++		return true;
++	if (S_ISREG(mode)) {
++		if (IS_ENABLED(CONFIG_BLOCK) &&
++		    io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
++		    file->f_op != &io_uring_fops)
++			return true;
++		return false;
++	}
++
++	/* any ->read/write should understand O_NONBLOCK */
++	if (file->f_flags & O_NONBLOCK)
++		return true;
++
++	if (!(file->f_mode & FMODE_NOWAIT))
++		return false;
++
++	if (rw == READ)
++		return file->f_op->read_iter != NULL;
++
++	return file->f_op->write_iter != NULL;
++}
++
++static bool io_file_supports_nowait(struct io_kiocb *req, int rw)
++{
++	if (rw == READ && (req->flags & REQ_F_NOWAIT_READ))
++		return true;
++	else if (rw == WRITE && (req->flags & REQ_F_NOWAIT_WRITE))
++		return true;
++
++	return __io_file_supports_nowait(req->file, rw);
++}
++
++static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe,
++		      int rw)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	struct kiocb *kiocb = &req->rw.kiocb;
++	struct file *file = req->file;
++	unsigned ioprio;
++	int ret;
++
++	if (!io_req_ffs_set(req) && S_ISREG(file_inode(file)->i_mode))
++		req->flags |= REQ_F_ISREG;
++
++	kiocb->ki_pos = READ_ONCE(sqe->off);
++	if (kiocb->ki_pos == -1) {
++		if (!(file->f_mode & FMODE_STREAM)) {
++			req->flags |= REQ_F_CUR_POS;
++			kiocb->ki_pos = file->f_pos;
++		} else {
++			kiocb->ki_pos = 0;
++		}
++	}
++	kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
++	kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
++	ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
++	if (unlikely(ret))
++		return ret;
++
++	/*
++	 * If the file is marked O_NONBLOCK, still allow retry for it if it
++	 * supports async. Otherwise it's impossible to use O_NONBLOCK files
++	 * reliably. If not, or it IOCB_NOWAIT is set, don't retry.
++	 */
++	if ((kiocb->ki_flags & IOCB_NOWAIT) ||
++	    ((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req, rw)))
++		req->flags |= REQ_F_NOWAIT;
++
++	ioprio = READ_ONCE(sqe->ioprio);
++	if (ioprio) {
++		ret = ioprio_check_cap(ioprio);
++		if (ret)
++			return ret;
++
++		kiocb->ki_ioprio = ioprio;
++	} else
++		kiocb->ki_ioprio = get_current_ioprio();
++
++	if (ctx->flags & IORING_SETUP_IOPOLL) {
++		if (!(kiocb->ki_flags & IOCB_DIRECT) ||
++		    !kiocb->ki_filp->f_op->iopoll)
++			return -EOPNOTSUPP;
++
++		kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE;
++		kiocb->ki_complete = io_complete_rw_iopoll;
++		req->iopoll_completed = 0;
++	} else {
++		if (kiocb->ki_flags & IOCB_HIPRI)
++			return -EINVAL;
++		kiocb->ki_complete = io_complete_rw;
++	}
++
++	/* used for fixed read/write too - just read unconditionally */
++	req->buf_index = READ_ONCE(sqe->buf_index);
++	req->imu = NULL;
++
++	if (req->opcode == IORING_OP_READ_FIXED ||
++	    req->opcode == IORING_OP_WRITE_FIXED) {
++		struct io_ring_ctx *ctx = req->ctx;
++		u16 index;
++
++		if (unlikely(req->buf_index >= ctx->nr_user_bufs))
++			return -EFAULT;
++		index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
++		req->imu = ctx->user_bufs[index];
++		io_req_set_rsrc_node(req);
++	}
++
++	req->rw.addr = READ_ONCE(sqe->addr);
++	req->rw.len = READ_ONCE(sqe->len);
++	return 0;
++}
++
++static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
++{
++	switch (ret) {
++	case -EIOCBQUEUED:
++		break;
++	case -ERESTARTSYS:
++	case -ERESTARTNOINTR:
++	case -ERESTARTNOHAND:
++	case -ERESTART_RESTARTBLOCK:
++		/*
++		 * We can't just restart the syscall, since previously
++		 * submitted sqes may already be in progress. Just fail this
++		 * IO with EINTR.
++		 */
++		ret = -EINTR;
++		fallthrough;
++	default:
++		kiocb->ki_complete(kiocb, ret, 0);
++	}
++}
++
++static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
++		       unsigned int issue_flags)
++{
++	struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
++
++	if (req->flags & REQ_F_CUR_POS)
++		req->file->f_pos = kiocb->ki_pos;
++	if (ret >= 0 && (kiocb->ki_complete == io_complete_rw))
++		__io_complete_rw(req, ret, 0, issue_flags);
++	else
++		io_rw_done(kiocb, ret);
++
++	if (req->flags & REQ_F_REISSUE) {
++		req->flags &= ~REQ_F_REISSUE;
++		if (io_resubmit_prep(req)) {
++			io_req_task_queue_reissue(req);
++		} else {
++			unsigned int cflags = io_put_rw_kbuf(req);
++			struct io_ring_ctx *ctx = req->ctx;
++
++			ret = io_fixup_rw_res(req, ret);
++			req_set_fail(req);
++			if (!(issue_flags & IO_URING_F_NONBLOCK)) {
++				mutex_lock(&ctx->uring_lock);
++				__io_req_complete(req, issue_flags, ret, cflags);
++				mutex_unlock(&ctx->uring_lock);
++			} else {
++				__io_req_complete(req, issue_flags, ret, cflags);
++			}
++		}
++	}
++}
++
++static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
++			     struct io_mapped_ubuf *imu)
++{
++	size_t len = req->rw.len;
++	u64 buf_end, buf_addr = req->rw.addr;
++	size_t offset;
++
++	if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
++		return -EFAULT;
++	/* not inside the mapped region */
++	if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
++		return -EFAULT;
++
++	/*
++	 * May not be a start of buffer, set size appropriately
++	 * and advance us to the beginning.
++	 */
++	offset = buf_addr - imu->ubuf;
++	iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
++
++	if (offset) {
++		/*
++		 * Don't use iov_iter_advance() here, as it's really slow for
++		 * using the latter parts of a big fixed buffer - it iterates
++		 * over each segment manually. We can cheat a bit here, because
++		 * we know that:
++		 *
++		 * 1) it's a BVEC iter, we set it up
++		 * 2) all bvecs are PAGE_SIZE in size, except potentially the
++		 *    first and last bvec
++		 *
++		 * So just find our index, and adjust the iterator afterwards.
++		 * If the offset is within the first bvec (or the whole first
++		 * bvec, just use iov_iter_advance(). This makes it easier
++		 * since we can just skip the first segment, which may not
++		 * be PAGE_SIZE aligned.
++		 */
++		const struct bio_vec *bvec = imu->bvec;
++
++		if (offset <= bvec->bv_len) {
++			iov_iter_advance(iter, offset);
++		} else {
++			unsigned long seg_skip;
++
++			/* skip first vec */
++			offset -= bvec->bv_len;
++			seg_skip = 1 + (offset >> PAGE_SHIFT);
++
++			iter->bvec = bvec + seg_skip;
++			iter->nr_segs -= seg_skip;
++			iter->count -= bvec->bv_len + offset;
++			iter->iov_offset = offset & ~PAGE_MASK;
++		}
++	}
++
++	return 0;
++}
++
++static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
++{
++	if (WARN_ON_ONCE(!req->imu))
++		return -EFAULT;
++	return __io_import_fixed(req, rw, iter, req->imu);
++}
++
++static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
++{
++	if (needs_lock)
++		mutex_unlock(&ctx->uring_lock);
++}
++
++static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
++{
++	/*
++	 * "Normal" inline submissions always hold the uring_lock, since we
++	 * grab it from the system call. Same is true for the SQPOLL offload.
++	 * The only exception is when we've detached the request and issue it
++	 * from an async worker thread, grab the lock for that case.
++	 */
++	if (needs_lock)
++		mutex_lock(&ctx->uring_lock);
++}
++
++static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
++					  int bgid, struct io_buffer *kbuf,
++					  bool needs_lock)
++{
++	struct io_buffer *head;
++
++	if (req->flags & REQ_F_BUFFER_SELECTED)
++		return kbuf;
++
++	io_ring_submit_lock(req->ctx, needs_lock);
++
++	lockdep_assert_held(&req->ctx->uring_lock);
++
++	head = xa_load(&req->ctx->io_buffers, bgid);
++	if (head) {
++		if (!list_empty(&head->list)) {
++			kbuf = list_last_entry(&head->list, struct io_buffer,
++							list);
++			list_del(&kbuf->list);
++		} else {
++			kbuf = head;
++			xa_erase(&req->ctx->io_buffers, bgid);
++		}
++		if (*len > kbuf->len)
++			*len = kbuf->len;
++	} else {
++		kbuf = ERR_PTR(-ENOBUFS);
++	}
++
++	io_ring_submit_unlock(req->ctx, needs_lock);
++
++	return kbuf;
++}
++
++static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
++					bool needs_lock)
++{
++	struct io_buffer *kbuf;
++	u16 bgid;
++
++	kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
++	bgid = req->buf_index;
++	kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
++	if (IS_ERR(kbuf))
++		return kbuf;
++	req->rw.addr = (u64) (unsigned long) kbuf;
++	req->flags |= REQ_F_BUFFER_SELECTED;
++	return u64_to_user_ptr(kbuf->addr);
++}
++
++#ifdef CONFIG_COMPAT
++static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
++				bool needs_lock)
++{
++	struct compat_iovec __user *uiov;
++	compat_ssize_t clen;
++	void __user *buf;
++	ssize_t len;
++
++	uiov = u64_to_user_ptr(req->rw.addr);
++	if (!access_ok(uiov, sizeof(*uiov)))
++		return -EFAULT;
++	if (__get_user(clen, &uiov->iov_len))
++		return -EFAULT;
++	if (clen < 0)
++		return -EINVAL;
++
++	len = clen;
++	buf = io_rw_buffer_select(req, &len, needs_lock);
++	if (IS_ERR(buf))
++		return PTR_ERR(buf);
++	iov[0].iov_base = buf;
++	iov[0].iov_len = (compat_size_t) len;
++	return 0;
++}
++#endif
++
++static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
++				      bool needs_lock)
++{
++	struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
++	void __user *buf;
++	ssize_t len;
++
++	if (copy_from_user(iov, uiov, sizeof(*uiov)))
++		return -EFAULT;
++
++	len = iov[0].iov_len;
++	if (len < 0)
++		return -EINVAL;
++	buf = io_rw_buffer_select(req, &len, needs_lock);
++	if (IS_ERR(buf))
++		return PTR_ERR(buf);
++	iov[0].iov_base = buf;
++	iov[0].iov_len = len;
++	return 0;
++}
++
++static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
++				    bool needs_lock)
++{
++	if (req->flags & REQ_F_BUFFER_SELECTED) {
++		struct io_buffer *kbuf;
++
++		kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
++		iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
++		iov[0].iov_len = kbuf->len;
++		return 0;
++	}
++	if (req->rw.len != 1)
++		return -EINVAL;
++
++#ifdef CONFIG_COMPAT
++	if (req->ctx->compat)
++		return io_compat_import(req, iov, needs_lock);
++#endif
++
++	return __io_iov_buffer_select(req, iov, needs_lock);
++}
++
++static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
++			   struct iov_iter *iter, bool needs_lock)
++{
++	void __user *buf = u64_to_user_ptr(req->rw.addr);
++	size_t sqe_len = req->rw.len;
++	u8 opcode = req->opcode;
++	ssize_t ret;
++
++	if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
++		*iovec = NULL;
++		return io_import_fixed(req, rw, iter);
++	}
++
++	/* buffer index only valid with fixed read/write, or buffer select  */
++	if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
++		return -EINVAL;
++
++	if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
++		if (req->flags & REQ_F_BUFFER_SELECT) {
++			buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
++			if (IS_ERR(buf))
++				return PTR_ERR(buf);
++			req->rw.len = sqe_len;
++		}
++
++		ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
++		*iovec = NULL;
++		return ret;
++	}
++
++	if (req->flags & REQ_F_BUFFER_SELECT) {
++		ret = io_iov_buffer_select(req, *iovec, needs_lock);
++		if (!ret)
++			iov_iter_init(iter, rw, *iovec, 1, (*iovec)->iov_len);
++		*iovec = NULL;
++		return ret;
++	}
++
++	return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
++			      req->ctx->compat);
++}
++
++static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
++{
++	return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
++}
++
++/*
++ * For files that don't have ->read_iter() and ->write_iter(), handle them
++ * by looping over ->read() or ->write() manually.
++ */
++static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
++{
++	struct kiocb *kiocb = &req->rw.kiocb;
++	struct file *file = req->file;
++	ssize_t ret = 0;
++
++	/*
++	 * Don't support polled IO through this interface, and we can't
++	 * support non-blocking either. For the latter, this just causes
++	 * the kiocb to be handled from an async context.
++	 */
++	if (kiocb->ki_flags & IOCB_HIPRI)
++		return -EOPNOTSUPP;
++	if (kiocb->ki_flags & IOCB_NOWAIT)
++		return -EAGAIN;
++
++	while (iov_iter_count(iter)) {
++		struct iovec iovec;
++		ssize_t nr;
++
++		if (!iov_iter_is_bvec(iter)) {
++			iovec = iov_iter_iovec(iter);
++		} else {
++			iovec.iov_base = u64_to_user_ptr(req->rw.addr);
++			iovec.iov_len = req->rw.len;
++		}
++
++		if (rw == READ) {
++			nr = file->f_op->read(file, iovec.iov_base,
++					      iovec.iov_len, io_kiocb_ppos(kiocb));
++		} else {
++			nr = file->f_op->write(file, iovec.iov_base,
++					       iovec.iov_len, io_kiocb_ppos(kiocb));
++		}
++
++		if (nr < 0) {
++			if (!ret)
++				ret = nr;
++			break;
++		}
++		ret += nr;
++		if (!iov_iter_is_bvec(iter)) {
++			iov_iter_advance(iter, nr);
++		} else {
++			req->rw.addr += nr;
++			req->rw.len -= nr;
++			if (!req->rw.len)
++				break;
++		}
++		if (nr != iovec.iov_len)
++			break;
++	}
++
++	return ret;
++}
++
++static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
++			  const struct iovec *fast_iov, struct iov_iter *iter)
++{
++	struct io_async_rw *rw = req->async_data;
++
++	memcpy(&rw->iter, iter, sizeof(*iter));
++	rw->free_iovec = iovec;
++	rw->bytes_done = 0;
++	/* can only be fixed buffers, no need to do anything */
++	if (iov_iter_is_bvec(iter))
++		return;
++	if (!iovec) {
++		unsigned iov_off = 0;
++
++		rw->iter.iov = rw->fast_iov;
++		if (iter->iov != fast_iov) {
++			iov_off = iter->iov - fast_iov;
++			rw->iter.iov += iov_off;
++		}
++		if (rw->fast_iov != fast_iov)
++			memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
++			       sizeof(struct iovec) * iter->nr_segs);
++	} else {
++		req->flags |= REQ_F_NEED_CLEANUP;
++	}
++}
++
++static inline int io_alloc_async_data(struct io_kiocb *req)
++{
++	WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
++	req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
++	return req->async_data == NULL;
++}
++
++static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
++			     const struct iovec *fast_iov,
++			     struct iov_iter *iter, bool force)
++{
++	if (!force && !io_op_defs[req->opcode].needs_async_setup)
++		return 0;
++	if (!req->async_data) {
++		struct io_async_rw *iorw;
++
++		if (io_alloc_async_data(req)) {
++			kfree(iovec);
++			return -ENOMEM;
++		}
++
++		io_req_map_rw(req, iovec, fast_iov, iter);
++		iorw = req->async_data;
++		/* we've copied and mapped the iter, ensure state is saved */
++		iov_iter_save_state(&iorw->iter, &iorw->iter_state);
++	}
++	return 0;
++}
++
++static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
++{
++	struct io_async_rw *iorw = req->async_data;
++	struct iovec *iov = iorw->fast_iov;
++	int ret;
++
++	ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
++	if (unlikely(ret < 0))
++		return ret;
++
++	iorw->bytes_done = 0;
++	iorw->free_iovec = iov;
++	if (iov)
++		req->flags |= REQ_F_NEED_CLEANUP;
++	iov_iter_save_state(&iorw->iter, &iorw->iter_state);
++	return 0;
++}
++
++static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	if (unlikely(!(req->file->f_mode & FMODE_READ)))
++		return -EBADF;
++	return io_prep_rw(req, sqe, READ);
++}
++
++/*
++ * This is our waitqueue callback handler, registered through lock_page_async()
++ * when we initially tried to do the IO with the iocb armed our waitqueue.
++ * This gets called when the page is unlocked, and we generally expect that to
++ * happen when the page IO is completed and the page is now uptodate. This will
++ * queue a task_work based retry of the operation, attempting to copy the data
++ * again. If the latter fails because the page was NOT uptodate, then we will
++ * do a thread based blocking retry of the operation. That's the unexpected
++ * slow path.
++ */
++static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
++			     int sync, void *arg)
++{
++	struct wait_page_queue *wpq;
++	struct io_kiocb *req = wait->private;
++	struct wait_page_key *key = arg;
++
++	wpq = container_of(wait, struct wait_page_queue, wait);
++
++	if (!wake_page_match(wpq, key))
++		return 0;
++
++	req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
++	list_del_init(&wait->entry);
++	io_req_task_queue(req);
++	return 1;
++}
++
++/*
++ * This controls whether a given IO request should be armed for async page
++ * based retry. If we return false here, the request is handed to the async
++ * worker threads for retry. If we're doing buffered reads on a regular file,
++ * we prepare a private wait_page_queue entry and retry the operation. This
++ * will either succeed because the page is now uptodate and unlocked, or it
++ * will register a callback when the page is unlocked at IO completion. Through
++ * that callback, io_uring uses task_work to setup a retry of the operation.
++ * That retry will attempt the buffered read again. The retry will generally
++ * succeed, or in rare cases where it fails, we then fall back to using the
++ * async worker threads for a blocking retry.
++ */
++static bool io_rw_should_retry(struct io_kiocb *req)
++{
++	struct io_async_rw *rw = req->async_data;
++	struct wait_page_queue *wait = &rw->wpq;
++	struct kiocb *kiocb = &req->rw.kiocb;
++
++	/* never retry for NOWAIT, we just complete with -EAGAIN */
++	if (req->flags & REQ_F_NOWAIT)
++		return false;
++
++	/* Only for buffered IO */
++	if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
++		return false;
++
++	/*
++	 * just use poll if we can, and don't attempt if the fs doesn't
++	 * support callback based unlocks
++	 */
++	if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
++		return false;
++
++	wait->wait.func = io_async_buf_func;
++	wait->wait.private = req;
++	wait->wait.flags = 0;
++	INIT_LIST_HEAD(&wait->wait.entry);
++	kiocb->ki_flags |= IOCB_WAITQ;
++	kiocb->ki_flags &= ~IOCB_NOWAIT;
++	kiocb->ki_waitq = wait;
++	return true;
++}
++
++static inline int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
++{
++	if (req->file->f_op->read_iter)
++		return call_read_iter(req->file, &req->rw.kiocb, iter);
++	else if (req->file->f_op->read)
++		return loop_rw_iter(READ, req, iter);
++	else
++		return -EINVAL;
++}
++
++static bool need_read_all(struct io_kiocb *req)
++{
++	return req->flags & REQ_F_ISREG ||
++		S_ISBLK(file_inode(req->file)->i_mode);
++}
++
++static int io_read(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
++	struct kiocb *kiocb = &req->rw.kiocb;
++	struct iov_iter __iter, *iter = &__iter;
++	struct io_async_rw *rw = req->async_data;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++	struct iov_iter_state __state, *state;
++	ssize_t ret, ret2;
++
++	if (rw) {
++		iter = &rw->iter;
++		state = &rw->iter_state;
++		/*
++		 * We come here from an earlier attempt, restore our state to
++		 * match in case it doesn't. It's cheap enough that we don't
++		 * need to make this conditional.
++		 */
++		iov_iter_restore(iter, state);
++		iovec = NULL;
++	} else {
++		ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
++		if (ret < 0)
++			return ret;
++		state = &__state;
++		iov_iter_save_state(iter, state);
++	}
++	req->result = iov_iter_count(iter);
++
++	/* Ensure we clear previously set non-block flag */
++	if (!force_nonblock)
++		kiocb->ki_flags &= ~IOCB_NOWAIT;
++	else
++		kiocb->ki_flags |= IOCB_NOWAIT;
++
++	/* If the file doesn't support async, just async punt */
++	if (force_nonblock && !io_file_supports_nowait(req, READ)) {
++		ret = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
++		return ret ?: -EAGAIN;
++	}
++
++	ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), req->result);
++	if (unlikely(ret)) {
++		kfree(iovec);
++		return ret;
++	}
++
++	ret = io_iter_do_read(req, iter);
++
++	if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
++		req->flags &= ~REQ_F_REISSUE;
++		/* IOPOLL retry should happen for io-wq threads */
++		if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
++			goto done;
++		/* no retry on NONBLOCK nor RWF_NOWAIT */
++		if (req->flags & REQ_F_NOWAIT)
++			goto done;
++		ret = 0;
++	} else if (ret == -EIOCBQUEUED) {
++		goto out_free;
++	} else if (ret <= 0 || ret == req->result || !force_nonblock ||
++		   (req->flags & REQ_F_NOWAIT) || !need_read_all(req)) {
++		/* read all, failed, already did sync or don't want to retry */
++		goto done;
++	}
++
++	/*
++	 * Don't depend on the iter state matching what was consumed, or being
++	 * untouched in case of error. Restore it and we'll advance it
++	 * manually if we need to.
++	 */
++	iov_iter_restore(iter, state);
++
++	ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
++	if (ret2)
++		return ret2;
++
++	iovec = NULL;
++	rw = req->async_data;
++	/*
++	 * Now use our persistent iterator and state, if we aren't already.
++	 * We've restored and mapped the iter to match.
++	 */
++	if (iter != &rw->iter) {
++		iter = &rw->iter;
++		state = &rw->iter_state;
++	}
++
++	do {
++		/*
++		 * We end up here because of a partial read, either from
++		 * above or inside this loop. Advance the iter by the bytes
++		 * that were consumed.
++		 */
++		iov_iter_advance(iter, ret);
++		if (!iov_iter_count(iter))
++			break;
++		rw->bytes_done += ret;
++		iov_iter_save_state(iter, state);
++
++		/* if we can retry, do so with the callbacks armed */
++		if (!io_rw_should_retry(req)) {
++			kiocb->ki_flags &= ~IOCB_WAITQ;
++			return -EAGAIN;
++		}
++
++		req->result = iov_iter_count(iter);
++		/*
++		 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
++		 * we get -EIOCBQUEUED, then we'll get a notification when the
++		 * desired page gets unlocked. We can also get a partial read
++		 * here, and if we do, then just retry at the new offset.
++		 */
++		ret = io_iter_do_read(req, iter);
++		if (ret == -EIOCBQUEUED)
++			return 0;
++		/* we got some bytes, but not all. retry. */
++		kiocb->ki_flags &= ~IOCB_WAITQ;
++		iov_iter_restore(iter, state);
++	} while (ret > 0);
++done:
++	kiocb_done(kiocb, ret, issue_flags);
++out_free:
++	/* it's faster to check here then delegate to kfree */
++	if (iovec)
++		kfree(iovec);
++	return 0;
++}
++
++static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
++		return -EBADF;
++	return io_prep_rw(req, sqe, WRITE);
++}
++
++static int io_write(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
++	struct kiocb *kiocb = &req->rw.kiocb;
++	struct iov_iter __iter, *iter = &__iter;
++	struct io_async_rw *rw = req->async_data;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++	struct iov_iter_state __state, *state;
++	ssize_t ret, ret2;
++
++	if (rw) {
++		iter = &rw->iter;
++		state = &rw->iter_state;
++		iov_iter_restore(iter, state);
++		iovec = NULL;
++	} else {
++		ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
++		if (ret < 0)
++			return ret;
++		state = &__state;
++		iov_iter_save_state(iter, state);
++	}
++	req->result = iov_iter_count(iter);
++
++	/* Ensure we clear previously set non-block flag */
++	if (!force_nonblock)
++		kiocb->ki_flags &= ~IOCB_NOWAIT;
++	else
++		kiocb->ki_flags |= IOCB_NOWAIT;
++
++	/* If the file doesn't support async, just async punt */
++	if (force_nonblock && !io_file_supports_nowait(req, WRITE))
++		goto copy_iov;
++
++	/* file path doesn't support NOWAIT for non-direct_IO */
++	if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
++	    (req->flags & REQ_F_ISREG))
++		goto copy_iov;
++
++	ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), req->result);
++	if (unlikely(ret))
++		goto out_free;
++
++	/*
++	 * Open-code file_start_write here to grab freeze protection,
++	 * which will be released by another thread in
++	 * io_complete_rw().  Fool lockdep by telling it the lock got
++	 * released so that it doesn't complain about the held lock when
++	 * we return to userspace.
++	 */
++	if (req->flags & REQ_F_ISREG) {
++		sb_start_write(file_inode(req->file)->i_sb);
++		__sb_writers_release(file_inode(req->file)->i_sb,
++					SB_FREEZE_WRITE);
++	}
++	kiocb->ki_flags |= IOCB_WRITE;
++
++	if (req->file->f_op->write_iter)
++		ret2 = call_write_iter(req->file, kiocb, iter);
++	else if (req->file->f_op->write)
++		ret2 = loop_rw_iter(WRITE, req, iter);
++	else
++		ret2 = -EINVAL;
++
++	if (req->flags & REQ_F_REISSUE) {
++		req->flags &= ~REQ_F_REISSUE;
++		ret2 = -EAGAIN;
++	}
++
++	/*
++	 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
++	 * retry them without IOCB_NOWAIT.
++	 */
++	if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
++		ret2 = -EAGAIN;
++	/* no retry on NONBLOCK nor RWF_NOWAIT */
++	if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
++		goto done;
++	if (!force_nonblock || ret2 != -EAGAIN) {
++		/* IOPOLL retry should happen for io-wq threads */
++		if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
++			goto copy_iov;
++done:
++		kiocb_done(kiocb, ret2, issue_flags);
++	} else {
++copy_iov:
++		iov_iter_restore(iter, state);
++		ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
++		if (!ret) {
++			if (kiocb->ki_flags & IOCB_WRITE)
++				kiocb_end_write(req);
++			return -EAGAIN;
++		}
++		return ret;
++	}
++out_free:
++	/* it's reportedly faster than delegating the null check to kfree() */
++	if (iovec)
++		kfree(iovec);
++	return ret;
++}
++
++static int io_renameat_prep(struct io_kiocb *req,
++			    const struct io_uring_sqe *sqe)
++{
++	struct io_rename *ren = &req->rename;
++	const char __user *oldf, *newf;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->flags & REQ_F_FIXED_FILE))
++		return -EBADF;
++
++	ren->old_dfd = READ_ONCE(sqe->fd);
++	oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
++	ren->new_dfd = READ_ONCE(sqe->len);
++	ren->flags = READ_ONCE(sqe->rename_flags);
++
++	ren->oldpath = getname(oldf);
++	if (IS_ERR(ren->oldpath))
++		return PTR_ERR(ren->oldpath);
++
++	ren->newpath = getname(newf);
++	if (IS_ERR(ren->newpath)) {
++		putname(ren->oldpath);
++		return PTR_ERR(ren->newpath);
++	}
++
++	req->flags |= REQ_F_NEED_CLEANUP;
++	return 0;
++}
++
++static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_rename *ren = &req->rename;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
++				ren->newpath, ren->flags);
++
++	req->flags &= ~REQ_F_NEED_CLEANUP;
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int io_unlinkat_prep(struct io_kiocb *req,
++			    const struct io_uring_sqe *sqe)
++{
++	struct io_unlink *un = &req->unlink;
++	const char __user *fname;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
++	    sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->flags & REQ_F_FIXED_FILE))
++		return -EBADF;
++
++	un->dfd = READ_ONCE(sqe->fd);
++
++	un->flags = READ_ONCE(sqe->unlink_flags);
++	if (un->flags & ~AT_REMOVEDIR)
++		return -EINVAL;
++
++	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	un->filename = getname(fname);
++	if (IS_ERR(un->filename))
++		return PTR_ERR(un->filename);
++
++	req->flags |= REQ_F_NEED_CLEANUP;
++	return 0;
++}
++
++static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_unlink *un = &req->unlink;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	if (un->flags & AT_REMOVEDIR)
++		ret = do_rmdir(un->dfd, un->filename);
++	else
++		ret = do_unlinkat(un->dfd, un->filename);
++
++	req->flags &= ~REQ_F_NEED_CLEANUP;
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int io_mkdirat_prep(struct io_kiocb *req,
++			    const struct io_uring_sqe *sqe)
++{
++	struct io_mkdir *mkd = &req->mkdir;
++	const char __user *fname;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->off || sqe->rw_flags || sqe->buf_index ||
++	    sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->flags & REQ_F_FIXED_FILE))
++		return -EBADF;
++
++	mkd->dfd = READ_ONCE(sqe->fd);
++	mkd->mode = READ_ONCE(sqe->len);
++
++	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	mkd->filename = getname(fname);
++	if (IS_ERR(mkd->filename))
++		return PTR_ERR(mkd->filename);
++
++	req->flags |= REQ_F_NEED_CLEANUP;
++	return 0;
++}
++
++static int io_mkdirat(struct io_kiocb *req, int issue_flags)
++{
++	struct io_mkdir *mkd = &req->mkdir;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	ret = do_mkdirat(mkd->dfd, mkd->filename, mkd->mode);
++
++	req->flags &= ~REQ_F_NEED_CLEANUP;
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int io_symlinkat_prep(struct io_kiocb *req,
++			    const struct io_uring_sqe *sqe)
++{
++	struct io_symlink *sl = &req->symlink;
++	const char __user *oldpath, *newpath;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->len || sqe->rw_flags || sqe->buf_index ||
++	    sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->flags & REQ_F_FIXED_FILE))
++		return -EBADF;
++
++	sl->new_dfd = READ_ONCE(sqe->fd);
++	oldpath = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	newpath = u64_to_user_ptr(READ_ONCE(sqe->addr2));
++
++	sl->oldpath = getname(oldpath);
++	if (IS_ERR(sl->oldpath))
++		return PTR_ERR(sl->oldpath);
++
++	sl->newpath = getname(newpath);
++	if (IS_ERR(sl->newpath)) {
++		putname(sl->oldpath);
++		return PTR_ERR(sl->newpath);
++	}
++
++	req->flags |= REQ_F_NEED_CLEANUP;
++	return 0;
++}
++
++static int io_symlinkat(struct io_kiocb *req, int issue_flags)
++{
++	struct io_symlink *sl = &req->symlink;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	ret = do_symlinkat(sl->oldpath, sl->new_dfd, sl->newpath);
++
++	req->flags &= ~REQ_F_NEED_CLEANUP;
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int io_linkat_prep(struct io_kiocb *req,
++			    const struct io_uring_sqe *sqe)
++{
++	struct io_hardlink *lnk = &req->hardlink;
++	const char __user *oldf, *newf;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->flags & REQ_F_FIXED_FILE))
++		return -EBADF;
++
++	lnk->old_dfd = READ_ONCE(sqe->fd);
++	lnk->new_dfd = READ_ONCE(sqe->len);
++	oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
++	lnk->flags = READ_ONCE(sqe->hardlink_flags);
++
++	lnk->oldpath = getname(oldf);
++	if (IS_ERR(lnk->oldpath))
++		return PTR_ERR(lnk->oldpath);
++
++	lnk->newpath = getname(newf);
++	if (IS_ERR(lnk->newpath)) {
++		putname(lnk->oldpath);
++		return PTR_ERR(lnk->newpath);
++	}
++
++	req->flags |= REQ_F_NEED_CLEANUP;
++	return 0;
++}
++
++static int io_linkat(struct io_kiocb *req, int issue_flags)
++{
++	struct io_hardlink *lnk = &req->hardlink;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	ret = do_linkat(lnk->old_dfd, lnk->oldpath, lnk->new_dfd,
++				lnk->newpath, lnk->flags);
++
++	req->flags &= ~REQ_F_NEED_CLEANUP;
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int io_shutdown_prep(struct io_kiocb *req,
++			    const struct io_uring_sqe *sqe)
++{
++#if defined(CONFIG_NET)
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (unlikely(sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags ||
++		     sqe->buf_index || sqe->splice_fd_in))
++		return -EINVAL;
++
++	req->shutdown.how = READ_ONCE(sqe->len);
++	return 0;
++#else
++	return -EOPNOTSUPP;
++#endif
++}
++
++static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
++{
++#if defined(CONFIG_NET)
++	struct socket *sock;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	sock = sock_from_file(req->file);
++	if (unlikely(!sock))
++		return -ENOTSOCK;
++
++	ret = __sys_shutdown_sock(sock, req->shutdown.how);
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++#else
++	return -EOPNOTSUPP;
++#endif
++}
++
++static int __io_splice_prep(struct io_kiocb *req,
++			    const struct io_uring_sqe *sqe)
++{
++	struct io_splice *sp = &req->splice;
++	unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++
++	sp->len = READ_ONCE(sqe->len);
++	sp->flags = READ_ONCE(sqe->splice_flags);
++	if (unlikely(sp->flags & ~valid_flags))
++		return -EINVAL;
++	sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in);
++	return 0;
++}
++
++static int io_tee_prep(struct io_kiocb *req,
++		       const struct io_uring_sqe *sqe)
++{
++	if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
++		return -EINVAL;
++	return __io_splice_prep(req, sqe);
++}
++
++static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_splice *sp = &req->splice;
++	struct file *out = sp->file_out;
++	unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
++	struct file *in;
++	long ret = 0;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	in = io_file_get(req->ctx, req, sp->splice_fd_in,
++				  (sp->flags & SPLICE_F_FD_IN_FIXED));
++	if (!in) {
++		ret = -EBADF;
++		goto done;
++	}
++
++	if (sp->len)
++		ret = do_tee(in, out, sp->len, flags);
++
++	if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
++		io_put_file(in);
++done:
++	if (ret != sp->len)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct io_splice *sp = &req->splice;
++
++	sp->off_in = READ_ONCE(sqe->splice_off_in);
++	sp->off_out = READ_ONCE(sqe->off);
++	return __io_splice_prep(req, sqe);
++}
++
++static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_splice *sp = &req->splice;
++	struct file *out = sp->file_out;
++	unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
++	loff_t *poff_in, *poff_out;
++	struct file *in;
++	long ret = 0;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	in = io_file_get(req->ctx, req, sp->splice_fd_in,
++				  (sp->flags & SPLICE_F_FD_IN_FIXED));
++	if (!in) {
++		ret = -EBADF;
++		goto done;
++	}
++
++	poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
++	poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
++
++	if (sp->len)
++		ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
++
++	if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
++		io_put_file(in);
++done:
++	if (ret != sp->len)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++/*
++ * IORING_OP_NOP just posts a completion event, nothing else.
++ */
++static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++
++	__io_req_complete(req, issue_flags, 0, 0);
++	return 0;
++}
++
++static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
++		     sqe->splice_fd_in))
++		return -EINVAL;
++
++	req->sync.flags = READ_ONCE(sqe->fsync_flags);
++	if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
++		return -EINVAL;
++
++	req->sync.off = READ_ONCE(sqe->off);
++	req->sync.len = READ_ONCE(sqe->len);
++	return 0;
++}
++
++static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
++{
++	loff_t end = req->sync.off + req->sync.len;
++	int ret;
++
++	/* fsync always requires a blocking context */
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	ret = vfs_fsync_range(req->file, req->sync.off,
++				end > 0 ? end : LLONG_MAX,
++				req->sync.flags & IORING_FSYNC_DATASYNC);
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int io_fallocate_prep(struct io_kiocb *req,
++			     const struct io_uring_sqe *sqe)
++{
++	if (sqe->ioprio || sqe->buf_index || sqe->rw_flags ||
++	    sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++
++	req->sync.off = READ_ONCE(sqe->off);
++	req->sync.len = READ_ONCE(sqe->addr);
++	req->sync.mode = READ_ONCE(sqe->len);
++	return 0;
++}
++
++static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
++{
++	int ret;
++
++	/* fallocate always requiring blocking context */
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++	ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
++				req->sync.len);
++	if (ret < 0)
++		req_set_fail(req);
++	else
++		fsnotify_modify(req->file);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	const char __user *fname;
++	int ret;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (unlikely(sqe->ioprio || sqe->buf_index))
++		return -EINVAL;
++	if (unlikely(req->flags & REQ_F_FIXED_FILE))
++		return -EBADF;
++
++	/* open.how should be already initialised */
++	if (!(req->open.how.flags & O_PATH) && force_o_largefile())
++		req->open.how.flags |= O_LARGEFILE;
++
++	req->open.dfd = READ_ONCE(sqe->fd);
++	fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	req->open.filename = getname(fname);
++	if (IS_ERR(req->open.filename)) {
++		ret = PTR_ERR(req->open.filename);
++		req->open.filename = NULL;
++		return ret;
++	}
++
++	req->open.file_slot = READ_ONCE(sqe->file_index);
++	if (req->open.file_slot && (req->open.how.flags & O_CLOEXEC))
++		return -EINVAL;
++
++	req->open.nofile = rlimit(RLIMIT_NOFILE);
++	req->flags |= REQ_F_NEED_CLEANUP;
++	return 0;
++}
++
++static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	u64 mode = READ_ONCE(sqe->len);
++	u64 flags = READ_ONCE(sqe->open_flags);
++
++	req->open.how = build_open_how(flags, mode);
++	return __io_openat_prep(req, sqe);
++}
++
++static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct open_how __user *how;
++	size_t len;
++	int ret;
++
++	how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
++	len = READ_ONCE(sqe->len);
++	if (len < OPEN_HOW_SIZE_VER0)
++		return -EINVAL;
++
++	ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
++					len);
++	if (ret)
++		return ret;
++
++	return __io_openat_prep(req, sqe);
++}
++
++static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct open_flags op;
++	struct file *file;
++	bool resolve_nonblock, nonblock_set;
++	bool fixed = !!req->open.file_slot;
++	int ret;
++
++	ret = build_open_flags(&req->open.how, &op);
++	if (ret)
++		goto err;
++	nonblock_set = op.open_flag & O_NONBLOCK;
++	resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
++	if (issue_flags & IO_URING_F_NONBLOCK) {
++		/*
++		 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
++		 * it'll always -EAGAIN
++		 */
++		if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
++			return -EAGAIN;
++		op.lookup_flags |= LOOKUP_CACHED;
++		op.open_flag |= O_NONBLOCK;
++	}
++
++	if (!fixed) {
++		ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
++		if (ret < 0)
++			goto err;
++	}
++
++	file = do_filp_open(req->open.dfd, req->open.filename, &op);
++	if (IS_ERR(file)) {
++		/*
++		 * We could hang on to this 'fd' on retrying, but seems like
++		 * marginal gain for something that is now known to be a slower
++		 * path. So just put it, and we'll get a new one when we retry.
++		 */
++		if (!fixed)
++			put_unused_fd(ret);
++
++		ret = PTR_ERR(file);
++		/* only retry if RESOLVE_CACHED wasn't already set by application */
++		if (ret == -EAGAIN &&
++		    (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)))
++			return -EAGAIN;
++		goto err;
++	}
++
++	if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
++		file->f_flags &= ~O_NONBLOCK;
++	fsnotify_open(file);
++
++	if (!fixed)
++		fd_install(ret, file);
++	else
++		ret = io_install_fixed_file(req, file, issue_flags,
++					    req->open.file_slot - 1);
++err:
++	putname(req->open.filename);
++	req->flags &= ~REQ_F_NEED_CLEANUP;
++	if (ret < 0)
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++
++static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
++{
++	return io_openat2(req, issue_flags);
++}
++
++static int io_remove_buffers_prep(struct io_kiocb *req,
++				  const struct io_uring_sqe *sqe)
++{
++	struct io_provide_buf *p = &req->pbuf;
++	u64 tmp;
++
++	if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off ||
++	    sqe->splice_fd_in)
++		return -EINVAL;
++
++	tmp = READ_ONCE(sqe->fd);
++	if (!tmp || tmp > USHRT_MAX)
++		return -EINVAL;
++
++	memset(p, 0, sizeof(*p));
++	p->nbufs = tmp;
++	p->bgid = READ_ONCE(sqe->buf_group);
++	return 0;
++}
++
++static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
++			       int bgid, unsigned nbufs)
++{
++	unsigned i = 0;
++
++	/* shouldn't happen */
++	if (!nbufs)
++		return 0;
++
++	/* the head kbuf is the list itself */
++	while (!list_empty(&buf->list)) {
++		struct io_buffer *nxt;
++
++		nxt = list_first_entry(&buf->list, struct io_buffer, list);
++		list_del(&nxt->list);
++		kfree(nxt);
++		if (++i == nbufs)
++			return i;
++		cond_resched();
++	}
++	i++;
++	kfree(buf);
++	xa_erase(&ctx->io_buffers, bgid);
++
++	return i;
++}
++
++static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_provide_buf *p = &req->pbuf;
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_buffer *head;
++	int ret = 0;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++
++	io_ring_submit_lock(ctx, !force_nonblock);
++
++	lockdep_assert_held(&ctx->uring_lock);
++
++	ret = -ENOENT;
++	head = xa_load(&ctx->io_buffers, p->bgid);
++	if (head)
++		ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
++	if (ret < 0)
++		req_set_fail(req);
++
++	/* complete before unlock, IOPOLL may need the lock */
++	__io_req_complete(req, issue_flags, ret, 0);
++	io_ring_submit_unlock(ctx, !force_nonblock);
++	return 0;
++}
++
++static int io_provide_buffers_prep(struct io_kiocb *req,
++				   const struct io_uring_sqe *sqe)
++{
++	unsigned long size, tmp_check;
++	struct io_provide_buf *p = &req->pbuf;
++	u64 tmp;
++
++	if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
++		return -EINVAL;
++
++	tmp = READ_ONCE(sqe->fd);
++	if (!tmp || tmp > USHRT_MAX)
++		return -E2BIG;
++	p->nbufs = tmp;
++	p->addr = READ_ONCE(sqe->addr);
++	p->len = READ_ONCE(sqe->len);
++
++	if (check_mul_overflow((unsigned long)p->len, (unsigned long)p->nbufs,
++				&size))
++		return -EOVERFLOW;
++	if (check_add_overflow((unsigned long)p->addr, size, &tmp_check))
++		return -EOVERFLOW;
++
++	size = (unsigned long)p->len * p->nbufs;
++	if (!access_ok(u64_to_user_ptr(p->addr), size))
++		return -EFAULT;
++
++	p->bgid = READ_ONCE(sqe->buf_group);
++	tmp = READ_ONCE(sqe->off);
++	if (tmp > USHRT_MAX)
++		return -E2BIG;
++	p->bid = tmp;
++	return 0;
++}
++
++static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
++{
++	struct io_buffer *buf;
++	u64 addr = pbuf->addr;
++	int i, bid = pbuf->bid;
++
++	for (i = 0; i < pbuf->nbufs; i++) {
++		buf = kmalloc(sizeof(*buf), GFP_KERNEL_ACCOUNT);
++		if (!buf)
++			break;
++
++		buf->addr = addr;
++		buf->len = min_t(__u32, pbuf->len, MAX_RW_COUNT);
++		buf->bid = bid;
++		addr += pbuf->len;
++		bid++;
++		if (!*head) {
++			INIT_LIST_HEAD(&buf->list);
++			*head = buf;
++		} else {
++			list_add_tail(&buf->list, &(*head)->list);
++		}
++		cond_resched();
++	}
++
++	return i ? i : -ENOMEM;
++}
++
++static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_provide_buf *p = &req->pbuf;
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_buffer *head, *list;
++	int ret = 0;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++
++	io_ring_submit_lock(ctx, !force_nonblock);
++
++	lockdep_assert_held(&ctx->uring_lock);
++
++	list = head = xa_load(&ctx->io_buffers, p->bgid);
++
++	ret = io_add_buffers(p, &head);
++	if (ret >= 0 && !list) {
++		ret = xa_insert(&ctx->io_buffers, p->bgid, head,
++				GFP_KERNEL_ACCOUNT);
++		if (ret < 0)
++			__io_remove_buffers(ctx, head, p->bgid, -1U);
++	}
++	if (ret < 0)
++		req_set_fail(req);
++	/* complete before unlock, IOPOLL may need the lock */
++	__io_req_complete(req, issue_flags, ret, 0);
++	io_ring_submit_unlock(ctx, !force_nonblock);
++	return 0;
++}
++
++static int io_epoll_ctl_prep(struct io_kiocb *req,
++			     const struct io_uring_sqe *sqe)
++{
++#if defined(CONFIG_EPOLL)
++	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++
++	req->epoll.epfd = READ_ONCE(sqe->fd);
++	req->epoll.op = READ_ONCE(sqe->len);
++	req->epoll.fd = READ_ONCE(sqe->off);
++
++	if (ep_op_has_event(req->epoll.op)) {
++		struct epoll_event __user *ev;
++
++		ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
++		if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
++			return -EFAULT;
++	}
++
++	return 0;
++#else
++	return -EOPNOTSUPP;
++#endif
++}
++
++static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
++{
++#if defined(CONFIG_EPOLL)
++	struct io_epoll *ie = &req->epoll;
++	int ret;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++
++	ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
++	if (force_nonblock && ret == -EAGAIN)
++		return -EAGAIN;
++
++	if (ret < 0)
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++#else
++	return -EOPNOTSUPP;
++#endif
++}
++
++static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
++	if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++
++	req->madvise.addr = READ_ONCE(sqe->addr);
++	req->madvise.len = READ_ONCE(sqe->len);
++	req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
++	return 0;
++#else
++	return -EOPNOTSUPP;
++#endif
++}
++
++static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
++{
++#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
++	struct io_madvise *ma = &req->madvise;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++#else
++	return -EOPNOTSUPP;
++#endif
++}
++
++static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	if (sqe->ioprio || sqe->buf_index || sqe->addr || sqe->splice_fd_in)
++		return -EINVAL;
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++
++	req->fadvise.offset = READ_ONCE(sqe->off);
++	req->fadvise.len = READ_ONCE(sqe->len);
++	req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
++	return 0;
++}
++
++static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_fadvise *fa = &req->fadvise;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK) {
++		switch (fa->advice) {
++		case POSIX_FADV_NORMAL:
++		case POSIX_FADV_RANDOM:
++		case POSIX_FADV_SEQUENTIAL:
++			break;
++		default:
++			return -EAGAIN;
++		}
++	}
++
++	ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
++	if (ret < 0)
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++
++static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
++		return -EINVAL;
++	if (req->flags & REQ_F_FIXED_FILE)
++		return -EBADF;
++
++	req->statx.dfd = READ_ONCE(sqe->fd);
++	req->statx.mask = READ_ONCE(sqe->len);
++	req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
++	req->statx.flags = READ_ONCE(sqe->statx_flags);
++
++	return 0;
++}
++
++static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_statx *ctx = &req->statx;
++	int ret;
++
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
++		       ctx->buffer);
++
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
++	    sqe->rw_flags || sqe->buf_index)
++		return -EINVAL;
++	if (req->flags & REQ_F_FIXED_FILE)
++		return -EBADF;
++
++	req->close.fd = READ_ONCE(sqe->fd);
++	req->close.file_slot = READ_ONCE(sqe->file_index);
++	if (req->close.file_slot && req->close.fd)
++		return -EINVAL;
++
++	return 0;
++}
++
++static int io_close(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct files_struct *files = current->files;
++	struct io_close *close = &req->close;
++	struct fdtable *fdt;
++	struct file *file = NULL;
++	int ret = -EBADF;
++
++	if (req->close.file_slot) {
++		ret = io_close_fixed(req, issue_flags);
++		goto err;
++	}
++
++	spin_lock(&files->file_lock);
++	fdt = files_fdtable(files);
++	if (close->fd >= fdt->max_fds) {
++		spin_unlock(&files->file_lock);
++		goto err;
++	}
++	file = fdt->fd[close->fd];
++	if (!file || file->f_op == &io_uring_fops) {
++		spin_unlock(&files->file_lock);
++		file = NULL;
++		goto err;
++	}
++
++	/* if the file has a flush method, be safe and punt to async */
++	if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
++		spin_unlock(&files->file_lock);
++		return -EAGAIN;
++	}
++
++	ret = __close_fd_get_file(close->fd, &file);
++	spin_unlock(&files->file_lock);
++	if (ret < 0) {
++		if (ret == -ENOENT)
++			ret = -EBADF;
++		goto err;
++	}
++
++	/* No ->flush() or already async, safely close from here */
++	ret = filp_close(file, current->files);
++err:
++	if (ret < 0)
++		req_set_fail(req);
++	if (file)
++		fput(file);
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++
++static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
++		     sqe->splice_fd_in))
++		return -EINVAL;
++
++	req->sync.off = READ_ONCE(sqe->off);
++	req->sync.len = READ_ONCE(sqe->len);
++	req->sync.flags = READ_ONCE(sqe->sync_range_flags);
++	return 0;
++}
++
++static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
++{
++	int ret;
++
++	/* sync_file_range always requires a blocking context */
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		return -EAGAIN;
++
++	ret = sync_file_range(req->file, req->sync.off, req->sync.len,
++				req->sync.flags);
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete(req, ret);
++	return 0;
++}
++
++#if defined(CONFIG_NET)
++static int io_setup_async_msg(struct io_kiocb *req,
++			      struct io_async_msghdr *kmsg)
++{
++	struct io_async_msghdr *async_msg = req->async_data;
++
++	if (async_msg)
++		return -EAGAIN;
++	if (io_alloc_async_data(req)) {
++		kfree(kmsg->free_iov);
++		return -ENOMEM;
++	}
++	async_msg = req->async_data;
++	req->flags |= REQ_F_NEED_CLEANUP;
++	memcpy(async_msg, kmsg, sizeof(*kmsg));
++	if (async_msg->msg.msg_name)
++		async_msg->msg.msg_name = &async_msg->addr;
++	/* if were using fast_iov, set it to the new one */
++	if (!async_msg->free_iov)
++		async_msg->msg.msg_iter.iov = async_msg->fast_iov;
++
++	return -EAGAIN;
++}
++
++static int io_sendmsg_copy_hdr(struct io_kiocb *req,
++			       struct io_async_msghdr *iomsg)
++{
++	iomsg->msg.msg_name = &iomsg->addr;
++	iomsg->free_iov = iomsg->fast_iov;
++	return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
++				   req->sr_msg.msg_flags, &iomsg->free_iov);
++}
++
++static int io_sendmsg_prep_async(struct io_kiocb *req)
++{
++	int ret;
++
++	ret = io_sendmsg_copy_hdr(req, req->async_data);
++	if (!ret)
++		req->flags |= REQ_F_NEED_CLEANUP;
++	return ret;
++}
++
++static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct io_sr_msg *sr = &req->sr_msg;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (unlikely(sqe->addr2 || sqe->file_index))
++		return -EINVAL;
++	if (unlikely(sqe->addr2 || sqe->file_index || sqe->ioprio))
++		return -EINVAL;
++
++	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	sr->len = READ_ONCE(sqe->len);
++	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
++	if (sr->msg_flags & MSG_DONTWAIT)
++		req->flags |= REQ_F_NOWAIT;
++
++#ifdef CONFIG_COMPAT
++	if (req->ctx->compat)
++		sr->msg_flags |= MSG_CMSG_COMPAT;
++#endif
++	return 0;
++}
++
++static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_async_msghdr iomsg, *kmsg;
++	struct socket *sock;
++	unsigned flags;
++	int min_ret = 0;
++	int ret;
++
++	sock = sock_from_file(req->file);
++	if (unlikely(!sock))
++		return -ENOTSOCK;
++
++	kmsg = req->async_data;
++	if (!kmsg) {
++		ret = io_sendmsg_copy_hdr(req, &iomsg);
++		if (ret)
++			return ret;
++		kmsg = &iomsg;
++	}
++
++	flags = req->sr_msg.msg_flags;
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		flags |= MSG_DONTWAIT;
++	if (flags & MSG_WAITALL)
++		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
++
++	ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
++	if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
++		return io_setup_async_msg(req, kmsg);
++	if (ret == -ERESTARTSYS)
++		ret = -EINTR;
++
++	/* fast path, check for non-NULL to avoid function call */
++	if (kmsg->free_iov)
++		kfree(kmsg->free_iov);
++	req->flags &= ~REQ_F_NEED_CLEANUP;
++	if (ret < min_ret)
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++
++static int io_send(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_sr_msg *sr = &req->sr_msg;
++	struct msghdr msg;
++	struct iovec iov;
++	struct socket *sock;
++	unsigned flags;
++	int min_ret = 0;
++	int ret;
++
++	sock = sock_from_file(req->file);
++	if (unlikely(!sock))
++		return -ENOTSOCK;
++
++	ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
++	if (unlikely(ret))
++		return ret;
++
++	msg.msg_name = NULL;
++	msg.msg_control = NULL;
++	msg.msg_controllen = 0;
++	msg.msg_namelen = 0;
++
++	flags = req->sr_msg.msg_flags;
++	if (issue_flags & IO_URING_F_NONBLOCK)
++		flags |= MSG_DONTWAIT;
++	if (flags & MSG_WAITALL)
++		min_ret = iov_iter_count(&msg.msg_iter);
++
++	msg.msg_flags = flags;
++	ret = sock_sendmsg(sock, &msg);
++	if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
++		return -EAGAIN;
++	if (ret == -ERESTARTSYS)
++		ret = -EINTR;
++
++	if (ret < min_ret)
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++
++static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
++				 struct io_async_msghdr *iomsg)
++{
++	struct io_sr_msg *sr = &req->sr_msg;
++	struct iovec __user *uiov;
++	size_t iov_len;
++	int ret;
++
++	ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
++					&iomsg->uaddr, &uiov, &iov_len);
++	if (ret)
++		return ret;
++
++	if (req->flags & REQ_F_BUFFER_SELECT) {
++		if (iov_len > 1)
++			return -EINVAL;
++		if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
++			return -EFAULT;
++		sr->len = iomsg->fast_iov[0].iov_len;
++		iomsg->free_iov = NULL;
++	} else {
++		iomsg->free_iov = iomsg->fast_iov;
++		ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
++				     &iomsg->free_iov, &iomsg->msg.msg_iter,
++				     false);
++		if (ret > 0)
++			ret = 0;
++	}
++
++	return ret;
++}
++
++#ifdef CONFIG_COMPAT
++static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
++					struct io_async_msghdr *iomsg)
++{
++	struct io_sr_msg *sr = &req->sr_msg;
++	struct compat_iovec __user *uiov;
++	compat_uptr_t ptr;
++	compat_size_t len;
++	int ret;
++
++	ret = __get_compat_msghdr(&iomsg->msg, sr->umsg_compat, &iomsg->uaddr,
++				  &ptr, &len);
++	if (ret)
++		return ret;
++
++	uiov = compat_ptr(ptr);
++	if (req->flags & REQ_F_BUFFER_SELECT) {
++		compat_ssize_t clen;
++
++		if (len > 1)
++			return -EINVAL;
++		if (!access_ok(uiov, sizeof(*uiov)))
++			return -EFAULT;
++		if (__get_user(clen, &uiov->iov_len))
++			return -EFAULT;
++		if (clen < 0)
++			return -EINVAL;
++		sr->len = clen;
++		iomsg->free_iov = NULL;
++	} else {
++		iomsg->free_iov = iomsg->fast_iov;
++		ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
++				   UIO_FASTIOV, &iomsg->free_iov,
++				   &iomsg->msg.msg_iter, true);
++		if (ret < 0)
++			return ret;
++	}
++
++	return 0;
++}
++#endif
++
++static int io_recvmsg_copy_hdr(struct io_kiocb *req,
++			       struct io_async_msghdr *iomsg)
++{
++	iomsg->msg.msg_name = &iomsg->addr;
++
++#ifdef CONFIG_COMPAT
++	if (req->ctx->compat)
++		return __io_compat_recvmsg_copy_hdr(req, iomsg);
++#endif
++
++	return __io_recvmsg_copy_hdr(req, iomsg);
++}
++
++static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
++					       bool needs_lock)
++{
++	struct io_sr_msg *sr = &req->sr_msg;
++	struct io_buffer *kbuf;
++
++	kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
++	if (IS_ERR(kbuf))
++		return kbuf;
++
++	sr->kbuf = kbuf;
++	req->flags |= REQ_F_BUFFER_SELECTED;
++	return kbuf;
++}
++
++static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
++{
++	return io_put_kbuf(req, req->sr_msg.kbuf);
++}
++
++static int io_recvmsg_prep_async(struct io_kiocb *req)
++{
++	int ret;
++
++	ret = io_recvmsg_copy_hdr(req, req->async_data);
++	if (!ret)
++		req->flags |= REQ_F_NEED_CLEANUP;
++	return ret;
++}
++
++static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct io_sr_msg *sr = &req->sr_msg;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (unlikely(sqe->addr2 || sqe->file_index))
++		return -EINVAL;
++	if (unlikely(sqe->addr2 || sqe->file_index || sqe->ioprio))
++		return -EINVAL;
++
++	sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	sr->len = READ_ONCE(sqe->len);
++	sr->bgid = READ_ONCE(sqe->buf_group);
++	sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
++	if (sr->msg_flags & MSG_DONTWAIT)
++		req->flags |= REQ_F_NOWAIT;
++
++#ifdef CONFIG_COMPAT
++	if (req->ctx->compat)
++		sr->msg_flags |= MSG_CMSG_COMPAT;
++#endif
++	return 0;
++}
++
++static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_async_msghdr iomsg, *kmsg;
++	struct socket *sock;
++	struct io_buffer *kbuf;
++	unsigned flags;
++	int min_ret = 0;
++	int ret, cflags = 0;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++
++	sock = sock_from_file(req->file);
++	if (unlikely(!sock))
++		return -ENOTSOCK;
++
++	kmsg = req->async_data;
++	if (!kmsg) {
++		ret = io_recvmsg_copy_hdr(req, &iomsg);
++		if (ret)
++			return ret;
++		kmsg = &iomsg;
++	}
++
++	if (req->flags & REQ_F_BUFFER_SELECT) {
++		kbuf = io_recv_buffer_select(req, !force_nonblock);
++		if (IS_ERR(kbuf))
++			return PTR_ERR(kbuf);
++		kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
++		kmsg->fast_iov[0].iov_len = req->sr_msg.len;
++		iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov,
++				1, req->sr_msg.len);
++	}
++
++	flags = req->sr_msg.msg_flags;
++	if (force_nonblock)
++		flags |= MSG_DONTWAIT;
++	if (flags & MSG_WAITALL)
++		min_ret = iov_iter_count(&kmsg->msg.msg_iter);
++
++	ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
++					kmsg->uaddr, flags);
++	if (force_nonblock && ret == -EAGAIN)
++		return io_setup_async_msg(req, kmsg);
++	if (ret == -ERESTARTSYS)
++		ret = -EINTR;
++
++	if (req->flags & REQ_F_BUFFER_SELECTED)
++		cflags = io_put_recv_kbuf(req);
++	/* fast path, check for non-NULL to avoid function call */
++	if (kmsg->free_iov)
++		kfree(kmsg->free_iov);
++	req->flags &= ~REQ_F_NEED_CLEANUP;
++	if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, cflags);
++	return 0;
++}
++
++static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_buffer *kbuf;
++	struct io_sr_msg *sr = &req->sr_msg;
++	struct msghdr msg;
++	void __user *buf = sr->buf;
++	struct socket *sock;
++	struct iovec iov;
++	unsigned flags;
++	int min_ret = 0;
++	int ret, cflags = 0;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++
++	sock = sock_from_file(req->file);
++	if (unlikely(!sock))
++		return -ENOTSOCK;
++
++	if (req->flags & REQ_F_BUFFER_SELECT) {
++		kbuf = io_recv_buffer_select(req, !force_nonblock);
++		if (IS_ERR(kbuf))
++			return PTR_ERR(kbuf);
++		buf = u64_to_user_ptr(kbuf->addr);
++	}
++
++	ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
++	if (unlikely(ret))
++		goto out_free;
++
++	msg.msg_name = NULL;
++	msg.msg_control = NULL;
++	msg.msg_controllen = 0;
++	msg.msg_namelen = 0;
++	msg.msg_iocb = NULL;
++	msg.msg_flags = 0;
++
++	flags = req->sr_msg.msg_flags;
++	if (force_nonblock)
++		flags |= MSG_DONTWAIT;
++	if (flags & MSG_WAITALL)
++		min_ret = iov_iter_count(&msg.msg_iter);
++
++	ret = sock_recvmsg(sock, &msg, flags);
++	if (force_nonblock && ret == -EAGAIN)
++		return -EAGAIN;
++	if (ret == -ERESTARTSYS)
++		ret = -EINTR;
++out_free:
++	if (req->flags & REQ_F_BUFFER_SELECTED)
++		cflags = io_put_recv_kbuf(req);
++	if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, cflags);
++	return 0;
++}
++
++static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct io_accept *accept = &req->accept;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->len || sqe->buf_index)
++		return -EINVAL;
++
++	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
++	accept->flags = READ_ONCE(sqe->accept_flags);
++	accept->nofile = rlimit(RLIMIT_NOFILE);
++
++	accept->file_slot = READ_ONCE(sqe->file_index);
++	if (accept->file_slot && (accept->flags & SOCK_CLOEXEC))
++		return -EINVAL;
++	if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
++		return -EINVAL;
++	if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
++		accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
++	return 0;
++}
++
++static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_accept *accept = &req->accept;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++	unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
++	bool fixed = !!accept->file_slot;
++	struct file *file;
++	int ret, fd;
++
++	if (req->file->f_flags & O_NONBLOCK)
++		req->flags |= REQ_F_NOWAIT;
++
++	if (!fixed) {
++		fd = __get_unused_fd_flags(accept->flags, accept->nofile);
++		if (unlikely(fd < 0))
++			return fd;
++	}
++	file = do_accept(req->file, file_flags, accept->addr, accept->addr_len,
++			 accept->flags);
++	if (IS_ERR(file)) {
++		if (!fixed)
++			put_unused_fd(fd);
++		ret = PTR_ERR(file);
++		if (ret == -EAGAIN && force_nonblock)
++			return -EAGAIN;
++		if (ret == -ERESTARTSYS)
++			ret = -EINTR;
++		req_set_fail(req);
++	} else if (!fixed) {
++		fd_install(fd, file);
++		ret = fd;
++	} else {
++		ret = io_install_fixed_file(req, file, issue_flags,
++					    accept->file_slot - 1);
++	}
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++
++static int io_connect_prep_async(struct io_kiocb *req)
++{
++	struct io_async_connect *io = req->async_data;
++	struct io_connect *conn = &req->connect;
++
++	return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
++}
++
++static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct io_connect *conn = &req->connect;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags ||
++	    sqe->splice_fd_in)
++		return -EINVAL;
++
++	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
++	conn->addr_len =  READ_ONCE(sqe->addr2);
++	return 0;
++}
++
++static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_async_connect __io, *io;
++	unsigned file_flags;
++	int ret;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++
++	if (req->async_data) {
++		io = req->async_data;
++	} else {
++		ret = move_addr_to_kernel(req->connect.addr,
++						req->connect.addr_len,
++						&__io.address);
++		if (ret)
++			goto out;
++		io = &__io;
++	}
++
++	file_flags = force_nonblock ? O_NONBLOCK : 0;
++
++	ret = __sys_connect_file(req->file, &io->address,
++					req->connect.addr_len, file_flags);
++	if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
++		if (req->async_data)
++			return -EAGAIN;
++		if (io_alloc_async_data(req)) {
++			ret = -ENOMEM;
++			goto out;
++		}
++		memcpy(req->async_data, &__io, sizeof(__io));
++		return -EAGAIN;
++	}
++	if (ret == -ERESTARTSYS)
++		ret = -EINTR;
++out:
++	if (ret < 0)
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++#else /* !CONFIG_NET */
++#define IO_NETOP_FN(op)							\
++static int io_##op(struct io_kiocb *req, unsigned int issue_flags)	\
++{									\
++	return -EOPNOTSUPP;						\
++}
++
++#define IO_NETOP_PREP(op)						\
++IO_NETOP_FN(op)								\
++static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
++{									\
++	return -EOPNOTSUPP;						\
++}									\
++
++#define IO_NETOP_PREP_ASYNC(op)						\
++IO_NETOP_PREP(op)							\
++static int io_##op##_prep_async(struct io_kiocb *req)			\
++{									\
++	return -EOPNOTSUPP;						\
++}
++
++IO_NETOP_PREP_ASYNC(sendmsg);
++IO_NETOP_PREP_ASYNC(recvmsg);
++IO_NETOP_PREP_ASYNC(connect);
++IO_NETOP_PREP(accept);
++IO_NETOP_FN(send);
++IO_NETOP_FN(recv);
++#endif /* CONFIG_NET */
++
++struct io_poll_table {
++	struct poll_table_struct pt;
++	struct io_kiocb *req;
++	int nr_entries;
++	int error;
++};
++
++#define IO_POLL_CANCEL_FLAG	BIT(31)
++#define IO_POLL_RETRY_FLAG	BIT(30)
++#define IO_POLL_REF_MASK	GENMASK(29, 0)
++
++/*
++ * We usually have 1-2 refs taken, 128 is more than enough and we want to
++ * maximise the margin between this amount and the moment when it overflows.
++ */
++#define IO_POLL_REF_BIAS       128
++
++static bool io_poll_get_ownership_slowpath(struct io_kiocb *req)
++{
++	int v;
++
++	/*
++	 * poll_refs are already elevated and we don't have much hope for
++	 * grabbing the ownership. Instead of incrementing set a retry flag
++	 * to notify the loop that there might have been some change.
++	 */
++	v = atomic_fetch_or(IO_POLL_RETRY_FLAG, &req->poll_refs);
++	if (v & IO_POLL_REF_MASK)
++		return false;
++	return !(atomic_fetch_inc(&req->poll_refs) & IO_POLL_REF_MASK);
++}
++
++/*
++ * If refs part of ->poll_refs (see IO_POLL_REF_MASK) is 0, it's free. We can
++ * bump it and acquire ownership. It's disallowed to modify requests while not
++ * owning it, that prevents from races for enqueueing task_work's and b/w
++ * arming poll and wakeups.
++ */
++static inline bool io_poll_get_ownership(struct io_kiocb *req)
++{
++	if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS))
++		return io_poll_get_ownership_slowpath(req);
++	return !(atomic_fetch_inc(&req->poll_refs) & IO_POLL_REF_MASK);
++}
++
++static void io_poll_mark_cancelled(struct io_kiocb *req)
++{
++	atomic_or(IO_POLL_CANCEL_FLAG, &req->poll_refs);
++}
++
++static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
++{
++	/* pure poll stashes this in ->async_data, poll driven retry elsewhere */
++	if (req->opcode == IORING_OP_POLL_ADD)
++		return req->async_data;
++	return req->apoll->double_poll;
++}
++
++static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
++{
++	if (req->opcode == IORING_OP_POLL_ADD)
++		return &req->poll;
++	return &req->apoll->poll;
++}
++
++static void io_poll_req_insert(struct io_kiocb *req)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	struct hlist_head *list;
++
++	list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
++	hlist_add_head(&req->hash_node, list);
++}
++
++static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
++			      wait_queue_func_t wake_func)
++{
++	poll->head = NULL;
++#define IO_POLL_UNMASK	(EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
++	/* mask in events that we always want/need */
++	poll->events = events | IO_POLL_UNMASK;
++	INIT_LIST_HEAD(&poll->wait.entry);
++	init_waitqueue_func_entry(&poll->wait, wake_func);
++}
++
++static inline void io_poll_remove_entry(struct io_poll_iocb *poll)
++{
++	struct wait_queue_head *head = smp_load_acquire(&poll->head);
++
++	if (head) {
++		spin_lock_irq(&head->lock);
++		list_del_init(&poll->wait.entry);
++		poll->head = NULL;
++		spin_unlock_irq(&head->lock);
++	}
++}
++
++static void io_poll_remove_entries(struct io_kiocb *req)
++{
++	struct io_poll_iocb *poll = io_poll_get_single(req);
++	struct io_poll_iocb *poll_double = io_poll_get_double(req);
++
++	/*
++	 * While we hold the waitqueue lock and the waitqueue is nonempty,
++	 * wake_up_pollfree() will wait for us.  However, taking the waitqueue
++	 * lock in the first place can race with the waitqueue being freed.
++	 *
++	 * We solve this as eventpoll does: by taking advantage of the fact that
++	 * all users of wake_up_pollfree() will RCU-delay the actual free.  If
++	 * we enter rcu_read_lock() and see that the pointer to the queue is
++	 * non-NULL, we can then lock it without the memory being freed out from
++	 * under us.
++	 *
++	 * Keep holding rcu_read_lock() as long as we hold the queue lock, in
++	 * case the caller deletes the entry from the queue, leaving it empty.
++	 * In that case, only RCU prevents the queue memory from being freed.
++	 */
++	rcu_read_lock();
++	io_poll_remove_entry(poll);
++	if (poll_double)
++		io_poll_remove_entry(poll_double);
++	rcu_read_unlock();
++}
++
++/*
++ * All poll tw should go through this. Checks for poll events, manages
++ * references, does rewait, etc.
++ *
++ * Returns a negative error on failure. >0 when no action require, which is
++ * either spurious wakeup or multishot CQE is served. 0 when it's done with
++ * the request, then the mask is stored in req->result.
++ */
++static int io_poll_check_events(struct io_kiocb *req)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_poll_iocb *poll = io_poll_get_single(req);
++	int v;
++
++	/* req->task == current here, checking PF_EXITING is safe */
++	if (unlikely(req->task->flags & PF_EXITING))
++		io_poll_mark_cancelled(req);
++
++	do {
++		v = atomic_read(&req->poll_refs);
++
++		/* tw handler should be the owner, and so have some references */
++		if (WARN_ON_ONCE(!(v & IO_POLL_REF_MASK)))
++			return 0;
++		if (v & IO_POLL_CANCEL_FLAG)
++			return -ECANCELED;
++		/*
++		 * cqe.res contains only events of the first wake up
++		 * and all others are be lost. Redo vfs_poll() to get
++		 * up to date state.
++		 */
++		if ((v & IO_POLL_REF_MASK) != 1)
++			req->result = 0;
++		if (v & IO_POLL_RETRY_FLAG) {
++			req->result = 0;
++			/*
++			 * We won't find new events that came in between
++			 * vfs_poll and the ref put unless we clear the
++			 * flag in advance.
++			 */
++			atomic_andnot(IO_POLL_RETRY_FLAG, &req->poll_refs);
++			v &= ~IO_POLL_RETRY_FLAG;
++		}
++
++		if (!req->result) {
++			struct poll_table_struct pt = { ._key = poll->events };
++
++			req->result = vfs_poll(req->file, &pt) & poll->events;
++		}
++
++		/* multishot, just fill an CQE and proceed */
++		if (req->result && !(poll->events & EPOLLONESHOT)) {
++			__poll_t mask = mangle_poll(req->result & poll->events);
++			bool filled;
++
++			spin_lock(&ctx->completion_lock);
++			filled = io_fill_cqe_aux(ctx, req->user_data, mask,
++						 IORING_CQE_F_MORE);
++			io_commit_cqring(ctx);
++			spin_unlock(&ctx->completion_lock);
++			if (unlikely(!filled))
++				return -ECANCELED;
++			io_cqring_ev_posted(ctx);
++		} else if (req->result) {
++			return 0;
++		}
++
++		/* force the next iteration to vfs_poll() */
++		req->result = 0;
++
++		/*
++		 * Release all references, retry if someone tried to restart
++		 * task_work while we were executing it.
++		 */
++	} while (atomic_sub_return(v & IO_POLL_REF_MASK, &req->poll_refs) &
++					IO_POLL_REF_MASK);
++
++	return 1;
++}
++
++static void io_poll_task_func(struct io_kiocb *req, bool *locked)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	int ret;
++
++	ret = io_poll_check_events(req);
++	if (ret > 0)
++		return;
++
++	if (!ret) {
++		req->result = mangle_poll(req->result & req->poll.events);
++	} else {
++		req->result = ret;
++		req_set_fail(req);
++	}
++
++	io_poll_remove_entries(req);
++	spin_lock(&ctx->completion_lock);
++	hash_del(&req->hash_node);
++	spin_unlock(&ctx->completion_lock);
++	io_req_complete_post(req, req->result, 0);
++}
++
++static void io_apoll_task_func(struct io_kiocb *req, bool *locked)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	int ret;
++
++	ret = io_poll_check_events(req);
++	if (ret > 0)
++		return;
++
++	io_poll_remove_entries(req);
++	spin_lock(&ctx->completion_lock);
++	hash_del(&req->hash_node);
++	spin_unlock(&ctx->completion_lock);
++
++	if (!ret)
++		io_req_task_submit(req, locked);
++	else
++		io_req_complete_failed(req, ret);
++}
++
++static void __io_poll_execute(struct io_kiocb *req, int mask)
++{
++	req->result = mask;
++	if (req->opcode == IORING_OP_POLL_ADD)
++		req->io_task_work.func = io_poll_task_func;
++	else
++		req->io_task_work.func = io_apoll_task_func;
++
++	trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
++	io_req_task_work_add(req);
++}
++
++static inline void io_poll_execute(struct io_kiocb *req, int res)
++{
++	if (io_poll_get_ownership(req))
++		__io_poll_execute(req, res);
++}
++
++static void io_poll_cancel_req(struct io_kiocb *req)
++{
++	io_poll_mark_cancelled(req);
++	/* kick tw, which should complete the request */
++	io_poll_execute(req, 0);
++}
++
++static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
++			void *key)
++{
++	struct io_kiocb *req = wait->private;
++	struct io_poll_iocb *poll = container_of(wait, struct io_poll_iocb,
++						 wait);
++	__poll_t mask = key_to_poll(key);
++
++	if (unlikely(mask & POLLFREE)) {
++		io_poll_mark_cancelled(req);
++		/* we have to kick tw in case it's not already */
++		io_poll_execute(req, 0);
++
++		/*
++		 * If the waitqueue is being freed early but someone is already
++		 * holds ownership over it, we have to tear down the request as
++		 * best we can. That means immediately removing the request from
++		 * its waitqueue and preventing all further accesses to the
++		 * waitqueue via the request.
++		 */
++		list_del_init(&poll->wait.entry);
++
++		/*
++		 * Careful: this *must* be the last step, since as soon
++		 * as req->head is NULL'ed out, the request can be
++		 * completed and freed, since aio_poll_complete_work()
++		 * will no longer need to take the waitqueue lock.
++		 */
++		smp_store_release(&poll->head, NULL);
++		return 1;
++	}
++
++	/* for instances that support it check for an event match first */
++	if (mask && !(mask & poll->events))
++		return 0;
++
++	if (io_poll_get_ownership(req))
++		__io_poll_execute(req, mask);
++	return 1;
++}
++
++static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
++			    struct wait_queue_head *head,
++			    struct io_poll_iocb **poll_ptr)
++{
++	struct io_kiocb *req = pt->req;
++
++	/*
++	 * The file being polled uses multiple waitqueues for poll handling
++	 * (e.g. one for read, one for write). Setup a separate io_poll_iocb
++	 * if this happens.
++	 */
++	if (unlikely(pt->nr_entries)) {
++		struct io_poll_iocb *first = poll;
++
++		/* double add on the same waitqueue head, ignore */
++		if (first->head == head)
++			return;
++		/* already have a 2nd entry, fail a third attempt */
++		if (*poll_ptr) {
++			if ((*poll_ptr)->head == head)
++				return;
++			pt->error = -EINVAL;
++			return;
++		}
++
++		poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
++		if (!poll) {
++			pt->error = -ENOMEM;
++			return;
++		}
++		io_init_poll_iocb(poll, first->events, first->wait.func);
++		*poll_ptr = poll;
++	}
++
++	pt->nr_entries++;
++	poll->head = head;
++	poll->wait.private = req;
++
++	if (poll->events & EPOLLEXCLUSIVE)
++		add_wait_queue_exclusive(head, &poll->wait);
++	else
++		add_wait_queue(head, &poll->wait);
++}
++
++static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
++			       struct poll_table_struct *p)
++{
++	struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
++
++	__io_queue_proc(&pt->req->poll, pt, head,
++			(struct io_poll_iocb **) &pt->req->async_data);
++}
++
++static int __io_arm_poll_handler(struct io_kiocb *req,
++				 struct io_poll_iocb *poll,
++				 struct io_poll_table *ipt, __poll_t mask)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	INIT_HLIST_NODE(&req->hash_node);
++	io_init_poll_iocb(poll, mask, io_poll_wake);
++	poll->file = req->file;
++	poll->wait.private = req;
++
++	ipt->pt._key = mask;
++	ipt->req = req;
++	ipt->error = 0;
++	ipt->nr_entries = 0;
++
++	/*
++	 * Take the ownership to delay any tw execution up until we're done
++	 * with poll arming. see io_poll_get_ownership().
++	 */
++	atomic_set(&req->poll_refs, 1);
++	mask = vfs_poll(req->file, &ipt->pt) & poll->events;
++
++	if (mask && (poll->events & EPOLLONESHOT)) {
++		io_poll_remove_entries(req);
++		/* no one else has access to the req, forget about the ref */
++		return mask;
++	}
++	if (!mask && unlikely(ipt->error || !ipt->nr_entries)) {
++		io_poll_remove_entries(req);
++		if (!ipt->error)
++			ipt->error = -EINVAL;
++		return 0;
++	}
++
++	spin_lock(&ctx->completion_lock);
++	io_poll_req_insert(req);
++	spin_unlock(&ctx->completion_lock);
++
++	if (mask) {
++		/* can't multishot if failed, just queue the event we've got */
++		if (unlikely(ipt->error || !ipt->nr_entries)) {
++			poll->events |= EPOLLONESHOT;
++			ipt->error = 0;
++		}
++		__io_poll_execute(req, mask);
++		return 0;
++	}
++
++	/*
++	 * Try to release ownership. If we see a change of state, e.g.
++	 * poll was waken up, queue up a tw, it'll deal with it.
++	 */
++	if (atomic_cmpxchg(&req->poll_refs, 1, 0) != 1)
++		__io_poll_execute(req, 0);
++	return 0;
++}
++
++static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
++			       struct poll_table_struct *p)
++{
++	struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
++	struct async_poll *apoll = pt->req->apoll;
++
++	__io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
++}
++
++enum {
++	IO_APOLL_OK,
++	IO_APOLL_ABORTED,
++	IO_APOLL_READY
++};
++
++static int io_arm_poll_handler(struct io_kiocb *req)
++{
++	const struct io_op_def *def = &io_op_defs[req->opcode];
++	struct io_ring_ctx *ctx = req->ctx;
++	struct async_poll *apoll;
++	struct io_poll_table ipt;
++	__poll_t mask = EPOLLONESHOT | POLLERR | POLLPRI;
++	int ret;
++
++	if (!req->file || !file_can_poll(req->file))
++		return IO_APOLL_ABORTED;
++	if (req->flags & REQ_F_POLLED)
++		return IO_APOLL_ABORTED;
++	if (!def->pollin && !def->pollout)
++		return IO_APOLL_ABORTED;
++
++	if (def->pollin) {
++		mask |= POLLIN | POLLRDNORM;
++
++		/* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
++		if ((req->opcode == IORING_OP_RECVMSG) &&
++		    (req->sr_msg.msg_flags & MSG_ERRQUEUE))
++			mask &= ~POLLIN;
++	} else {
++		mask |= POLLOUT | POLLWRNORM;
++	}
++
++	apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
++	if (unlikely(!apoll))
++		return IO_APOLL_ABORTED;
++	apoll->double_poll = NULL;
++	req->apoll = apoll;
++	req->flags |= REQ_F_POLLED;
++	ipt.pt._qproc = io_async_queue_proc;
++
++	ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask);
++	if (ret || ipt.error)
++		return ret ? IO_APOLL_READY : IO_APOLL_ABORTED;
++
++	trace_io_uring_poll_arm(ctx, req, req->opcode, req->user_data,
++				mask, apoll->poll.events);
++	return IO_APOLL_OK;
++}
++
++/*
++ * Returns true if we found and killed one or more poll requests
++ */
++static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
++			       bool cancel_all)
++{
++	struct hlist_node *tmp;
++	struct io_kiocb *req;
++	bool found = false;
++	int i;
++
++	spin_lock(&ctx->completion_lock);
++	for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
++		struct hlist_head *list;
++
++		list = &ctx->cancel_hash[i];
++		hlist_for_each_entry_safe(req, tmp, list, hash_node) {
++			if (io_match_task_safe(req, tsk, cancel_all)) {
++				hlist_del_init(&req->hash_node);
++				io_poll_cancel_req(req);
++				found = true;
++			}
++		}
++	}
++	spin_unlock(&ctx->completion_lock);
++	return found;
++}
++
++static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, __u64 sqe_addr,
++				     bool poll_only)
++	__must_hold(&ctx->completion_lock)
++{
++	struct hlist_head *list;
++	struct io_kiocb *req;
++
++	list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
++	hlist_for_each_entry(req, list, hash_node) {
++		if (sqe_addr != req->user_data)
++			continue;
++		if (poll_only && req->opcode != IORING_OP_POLL_ADD)
++			continue;
++		return req;
++	}
++	return NULL;
++}
++
++static bool io_poll_disarm(struct io_kiocb *req)
++	__must_hold(&ctx->completion_lock)
++{
++	if (!io_poll_get_ownership(req))
++		return false;
++	io_poll_remove_entries(req);
++	hash_del(&req->hash_node);
++	return true;
++}
++
++static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr,
++			  bool poll_only)
++	__must_hold(&ctx->completion_lock)
++{
++	struct io_kiocb *req = io_poll_find(ctx, sqe_addr, poll_only);
++
++	if (!req)
++		return -ENOENT;
++	io_poll_cancel_req(req);
++	return 0;
++}
++
++static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
++				     unsigned int flags)
++{
++	u32 events;
++
++	events = READ_ONCE(sqe->poll32_events);
++#ifdef __BIG_ENDIAN
++	events = swahw32(events);
++#endif
++	if (!(flags & IORING_POLL_ADD_MULTI))
++		events |= EPOLLONESHOT;
++	return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
++}
++
++static int io_poll_update_prep(struct io_kiocb *req,
++			       const struct io_uring_sqe *sqe)
++{
++	struct io_poll_update *upd = &req->poll_update;
++	u32 flags;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
++		return -EINVAL;
++	flags = READ_ONCE(sqe->len);
++	if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA |
++		      IORING_POLL_ADD_MULTI))
++		return -EINVAL;
++	/* meaningless without update */
++	if (flags == IORING_POLL_ADD_MULTI)
++		return -EINVAL;
++
++	upd->old_user_data = READ_ONCE(sqe->addr);
++	upd->update_events = flags & IORING_POLL_UPDATE_EVENTS;
++	upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA;
++
++	upd->new_user_data = READ_ONCE(sqe->off);
++	if (!upd->update_user_data && upd->new_user_data)
++		return -EINVAL;
++	if (upd->update_events)
++		upd->events = io_poll_parse_events(sqe, flags);
++	else if (sqe->poll32_events)
++		return -EINVAL;
++
++	return 0;
++}
++
++static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	struct io_poll_iocb *poll = &req->poll;
++	u32 flags;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->addr)
++		return -EINVAL;
++	flags = READ_ONCE(sqe->len);
++	if (flags & ~IORING_POLL_ADD_MULTI)
++		return -EINVAL;
++
++	io_req_set_refcount(req);
++	poll->events = io_poll_parse_events(sqe, flags);
++	return 0;
++}
++
++static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_poll_iocb *poll = &req->poll;
++	struct io_poll_table ipt;
++	int ret;
++
++	ipt.pt._qproc = io_poll_queue_proc;
++
++	ret = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events);
++	if (!ret && ipt.error)
++		req_set_fail(req);
++	ret = ret ?: ipt.error;
++	if (ret)
++		__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++
++static int io_poll_update(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_kiocb *preq;
++	int ret2, ret = 0;
++
++	spin_lock(&ctx->completion_lock);
++	preq = io_poll_find(ctx, req->poll_update.old_user_data, true);
++	if (!preq || !io_poll_disarm(preq)) {
++		spin_unlock(&ctx->completion_lock);
++		ret = preq ? -EALREADY : -ENOENT;
++		goto out;
++	}
++	spin_unlock(&ctx->completion_lock);
++
++	if (req->poll_update.update_events || req->poll_update.update_user_data) {
++		/* only mask one event flags, keep behavior flags */
++		if (req->poll_update.update_events) {
++			preq->poll.events &= ~0xffff;
++			preq->poll.events |= req->poll_update.events & 0xffff;
++			preq->poll.events |= IO_POLL_UNMASK;
++		}
++		if (req->poll_update.update_user_data)
++			preq->user_data = req->poll_update.new_user_data;
++
++		ret2 = io_poll_add(preq, issue_flags);
++		/* successfully updated, don't complete poll request */
++		if (!ret2)
++			goto out;
++	}
++	req_set_fail(preq);
++	io_req_complete(preq, -ECANCELED);
++out:
++	if (ret < 0)
++		req_set_fail(req);
++	/* complete update request, we're done with it */
++	io_req_complete(req, ret);
++	return 0;
++}
++
++static void io_req_task_timeout(struct io_kiocb *req, bool *locked)
++{
++	req_set_fail(req);
++	io_req_complete_post(req, -ETIME, 0);
++}
++
++static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
++{
++	struct io_timeout_data *data = container_of(timer,
++						struct io_timeout_data, timer);
++	struct io_kiocb *req = data->req;
++	struct io_ring_ctx *ctx = req->ctx;
++	unsigned long flags;
++
++	spin_lock_irqsave(&ctx->timeout_lock, flags);
++	list_del_init(&req->timeout.list);
++	atomic_set(&req->ctx->cq_timeouts,
++		atomic_read(&req->ctx->cq_timeouts) + 1);
++	spin_unlock_irqrestore(&ctx->timeout_lock, flags);
++
++	req->io_task_work.func = io_req_task_timeout;
++	io_req_task_work_add(req);
++	return HRTIMER_NORESTART;
++}
++
++static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
++					   __u64 user_data)
++	__must_hold(&ctx->timeout_lock)
++{
++	struct io_timeout_data *io;
++	struct io_kiocb *req;
++	bool found = false;
++
++	list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
++		found = user_data == req->user_data;
++		if (found)
++			break;
++	}
++	if (!found)
++		return ERR_PTR(-ENOENT);
++
++	io = req->async_data;
++	if (hrtimer_try_to_cancel(&io->timer) == -1)
++		return ERR_PTR(-EALREADY);
++	list_del_init(&req->timeout.list);
++	return req;
++}
++
++static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
++	__must_hold(&ctx->completion_lock)
++	__must_hold(&ctx->timeout_lock)
++{
++	struct io_kiocb *req = io_timeout_extract(ctx, user_data);
++
++	if (IS_ERR(req))
++		return PTR_ERR(req);
++
++	req_set_fail(req);
++	io_fill_cqe_req(req, -ECANCELED, 0);
++	io_put_req_deferred(req);
++	return 0;
++}
++
++static clockid_t io_timeout_get_clock(struct io_timeout_data *data)
++{
++	switch (data->flags & IORING_TIMEOUT_CLOCK_MASK) {
++	case IORING_TIMEOUT_BOOTTIME:
++		return CLOCK_BOOTTIME;
++	case IORING_TIMEOUT_REALTIME:
++		return CLOCK_REALTIME;
++	default:
++		/* can't happen, vetted at prep time */
++		WARN_ON_ONCE(1);
++		fallthrough;
++	case 0:
++		return CLOCK_MONOTONIC;
++	}
++}
++
++static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
++				    struct timespec64 *ts, enum hrtimer_mode mode)
++	__must_hold(&ctx->timeout_lock)
++{
++	struct io_timeout_data *io;
++	struct io_kiocb *req;
++	bool found = false;
++
++	list_for_each_entry(req, &ctx->ltimeout_list, timeout.list) {
++		found = user_data == req->user_data;
++		if (found)
++			break;
++	}
++	if (!found)
++		return -ENOENT;
++
++	io = req->async_data;
++	if (hrtimer_try_to_cancel(&io->timer) == -1)
++		return -EALREADY;
++	hrtimer_init(&io->timer, io_timeout_get_clock(io), mode);
++	io->timer.function = io_link_timeout_fn;
++	hrtimer_start(&io->timer, timespec64_to_ktime(*ts), mode);
++	return 0;
++}
++
++static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
++			     struct timespec64 *ts, enum hrtimer_mode mode)
++	__must_hold(&ctx->timeout_lock)
++{
++	struct io_kiocb *req = io_timeout_extract(ctx, user_data);
++	struct io_timeout_data *data;
++
++	if (IS_ERR(req))
++		return PTR_ERR(req);
++
++	req->timeout.off = 0; /* noseq */
++	data = req->async_data;
++	list_add_tail(&req->timeout.list, &ctx->timeout_list);
++	hrtimer_init(&data->timer, io_timeout_get_clock(data), mode);
++	data->timer.function = io_timeout_fn;
++	hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
++	return 0;
++}
++
++static int io_timeout_remove_prep(struct io_kiocb *req,
++				  const struct io_uring_sqe *sqe)
++{
++	struct io_timeout_rem *tr = &req->timeout_rem;
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->buf_index || sqe->len || sqe->splice_fd_in)
++		return -EINVAL;
++
++	tr->ltimeout = false;
++	tr->addr = READ_ONCE(sqe->addr);
++	tr->flags = READ_ONCE(sqe->timeout_flags);
++	if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) {
++		if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
++			return -EINVAL;
++		if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
++			tr->ltimeout = true;
++		if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK|IORING_TIMEOUT_ABS))
++			return -EINVAL;
++		if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
++			return -EFAULT;
++	} else if (tr->flags) {
++		/* timeout removal doesn't support flags */
++		return -EINVAL;
++	}
++
++	return 0;
++}
++
++static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
++{
++	return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
++					    : HRTIMER_MODE_REL;
++}
++
++/*
++ * Remove or update an existing timeout command
++ */
++static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_timeout_rem *tr = &req->timeout_rem;
++	struct io_ring_ctx *ctx = req->ctx;
++	int ret;
++
++	if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE)) {
++		spin_lock(&ctx->completion_lock);
++		spin_lock_irq(&ctx->timeout_lock);
++		ret = io_timeout_cancel(ctx, tr->addr);
++		spin_unlock_irq(&ctx->timeout_lock);
++		spin_unlock(&ctx->completion_lock);
++	} else {
++		enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags);
++
++		spin_lock_irq(&ctx->timeout_lock);
++		if (tr->ltimeout)
++			ret = io_linked_timeout_update(ctx, tr->addr, &tr->ts, mode);
++		else
++			ret = io_timeout_update(ctx, tr->addr, &tr->ts, mode);
++		spin_unlock_irq(&ctx->timeout_lock);
++	}
++
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete_post(req, ret, 0);
++	return 0;
++}
++
++static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
++			   bool is_timeout_link)
++{
++	struct io_timeout_data *data;
++	unsigned flags;
++	u32 off = READ_ONCE(sqe->off);
++
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->buf_index || sqe->len != 1 ||
++	    sqe->splice_fd_in)
++		return -EINVAL;
++	if (off && is_timeout_link)
++		return -EINVAL;
++	flags = READ_ONCE(sqe->timeout_flags);
++	if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK))
++		return -EINVAL;
++	/* more than one clock specified is invalid, obviously */
++	if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
++		return -EINVAL;
++
++	INIT_LIST_HEAD(&req->timeout.list);
++	req->timeout.off = off;
++	if (unlikely(off && !req->ctx->off_timeout_used))
++		req->ctx->off_timeout_used = true;
++
++	if (!req->async_data && io_alloc_async_data(req))
++		return -ENOMEM;
++
++	data = req->async_data;
++	data->req = req;
++	data->flags = flags;
++
++	if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
++		return -EFAULT;
++
++	INIT_LIST_HEAD(&req->timeout.list);
++	data->mode = io_translate_timeout_mode(flags);
++	hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode);
++
++	if (is_timeout_link) {
++		struct io_submit_link *link = &req->ctx->submit_state.link;
++
++		if (!link->head)
++			return -EINVAL;
++		if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
++			return -EINVAL;
++		req->timeout.head = link->last;
++		link->last->flags |= REQ_F_ARM_LTIMEOUT;
++	}
++	return 0;
++}
++
++static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_timeout_data *data = req->async_data;
++	struct list_head *entry;
++	u32 tail, off = req->timeout.off;
++
++	spin_lock_irq(&ctx->timeout_lock);
++
++	/*
++	 * sqe->off holds how many events that need to occur for this
++	 * timeout event to be satisfied. If it isn't set, then this is
++	 * a pure timeout request, sequence isn't used.
++	 */
++	if (io_is_timeout_noseq(req)) {
++		entry = ctx->timeout_list.prev;
++		goto add;
++	}
++
++	tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
++	req->timeout.target_seq = tail + off;
++
++	/* Update the last seq here in case io_flush_timeouts() hasn't.
++	 * This is safe because ->completion_lock is held, and submissions
++	 * and completions are never mixed in the same ->completion_lock section.
++	 */
++	ctx->cq_last_tm_flush = tail;
++
++	/*
++	 * Insertion sort, ensuring the first entry in the list is always
++	 * the one we need first.
++	 */
++	list_for_each_prev(entry, &ctx->timeout_list) {
++		struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
++						  timeout.list);
++
++		if (io_is_timeout_noseq(nxt))
++			continue;
++		/* nxt.seq is behind @tail, otherwise would've been completed */
++		if (off >= nxt->timeout.target_seq - tail)
++			break;
++	}
++add:
++	list_add(&req->timeout.list, entry);
++	data->timer.function = io_timeout_fn;
++	hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
++	spin_unlock_irq(&ctx->timeout_lock);
++	return 0;
++}
++
++struct io_cancel_data {
++	struct io_ring_ctx *ctx;
++	u64 user_data;
++};
++
++static bool io_cancel_cb(struct io_wq_work *work, void *data)
++{
++	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
++	struct io_cancel_data *cd = data;
++
++	return req->ctx == cd->ctx && req->user_data == cd->user_data;
++}
++
++static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
++			       struct io_ring_ctx *ctx)
++{
++	struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, };
++	enum io_wq_cancel cancel_ret;
++	int ret = 0;
++
++	if (!tctx || !tctx->io_wq)
++		return -ENOENT;
++
++	cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false);
++	switch (cancel_ret) {
++	case IO_WQ_CANCEL_OK:
++		ret = 0;
++		break;
++	case IO_WQ_CANCEL_RUNNING:
++		ret = -EALREADY;
++		break;
++	case IO_WQ_CANCEL_NOTFOUND:
++		ret = -ENOENT;
++		break;
++	}
++
++	return ret;
++}
++
++static int io_try_cancel_userdata(struct io_kiocb *req, u64 sqe_addr)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	int ret;
++
++	WARN_ON_ONCE(!io_wq_current_is_worker() && req->task != current);
++
++	ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
++	if (ret != -ENOENT)
++		return ret;
++
++	spin_lock(&ctx->completion_lock);
++	spin_lock_irq(&ctx->timeout_lock);
++	ret = io_timeout_cancel(ctx, sqe_addr);
++	spin_unlock_irq(&ctx->timeout_lock);
++	if (ret != -ENOENT)
++		goto out;
++	ret = io_poll_cancel(ctx, sqe_addr, false);
++out:
++	spin_unlock(&ctx->completion_lock);
++	return ret;
++}
++
++static int io_async_cancel_prep(struct io_kiocb *req,
++				const struct io_uring_sqe *sqe)
++{
++	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
++		return -EINVAL;
++	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags ||
++	    sqe->splice_fd_in)
++		return -EINVAL;
++
++	req->cancel.addr = READ_ONCE(sqe->addr);
++	return 0;
++}
++
++static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	u64 sqe_addr = req->cancel.addr;
++	struct io_tctx_node *node;
++	int ret;
++
++	ret = io_try_cancel_userdata(req, sqe_addr);
++	if (ret != -ENOENT)
++		goto done;
++
++	/* slow path, try all io-wq's */
++	io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
++	ret = -ENOENT;
++	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
++		struct io_uring_task *tctx = node->task->io_uring;
++
++		ret = io_async_cancel_one(tctx, req->cancel.addr, ctx);
++		if (ret != -ENOENT)
++			break;
++	}
++	io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
++done:
++	if (ret < 0)
++		req_set_fail(req);
++	io_req_complete_post(req, ret, 0);
++	return 0;
++}
++
++static int io_rsrc_update_prep(struct io_kiocb *req,
++				const struct io_uring_sqe *sqe)
++{
++	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
++		return -EINVAL;
++	if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
++		return -EINVAL;
++
++	req->rsrc_update.offset = READ_ONCE(sqe->off);
++	req->rsrc_update.nr_args = READ_ONCE(sqe->len);
++	if (!req->rsrc_update.nr_args)
++		return -EINVAL;
++	req->rsrc_update.arg = READ_ONCE(sqe->addr);
++	return 0;
++}
++
++static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_uring_rsrc_update2 up;
++	int ret;
++
++	up.offset = req->rsrc_update.offset;
++	up.data = req->rsrc_update.arg;
++	up.nr = 0;
++	up.tags = 0;
++	up.resv = 0;
++	up.resv2 = 0;
++
++	io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
++	ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
++					&up, req->rsrc_update.nr_args);
++	io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
++
++	if (ret < 0)
++		req_set_fail(req);
++	__io_req_complete(req, issue_flags, ret, 0);
++	return 0;
++}
++
++static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
++{
++	switch (req->opcode) {
++	case IORING_OP_NOP:
++		return 0;
++	case IORING_OP_READV:
++	case IORING_OP_READ_FIXED:
++	case IORING_OP_READ:
++		return io_read_prep(req, sqe);
++	case IORING_OP_WRITEV:
++	case IORING_OP_WRITE_FIXED:
++	case IORING_OP_WRITE:
++		return io_write_prep(req, sqe);
++	case IORING_OP_POLL_ADD:
++		return io_poll_add_prep(req, sqe);
++	case IORING_OP_POLL_REMOVE:
++		return io_poll_update_prep(req, sqe);
++	case IORING_OP_FSYNC:
++		return io_fsync_prep(req, sqe);
++	case IORING_OP_SYNC_FILE_RANGE:
++		return io_sfr_prep(req, sqe);
++	case IORING_OP_SENDMSG:
++	case IORING_OP_SEND:
++		return io_sendmsg_prep(req, sqe);
++	case IORING_OP_RECVMSG:
++	case IORING_OP_RECV:
++		return io_recvmsg_prep(req, sqe);
++	case IORING_OP_CONNECT:
++		return io_connect_prep(req, sqe);
++	case IORING_OP_TIMEOUT:
++		return io_timeout_prep(req, sqe, false);
++	case IORING_OP_TIMEOUT_REMOVE:
++		return io_timeout_remove_prep(req, sqe);
++	case IORING_OP_ASYNC_CANCEL:
++		return io_async_cancel_prep(req, sqe);
++	case IORING_OP_LINK_TIMEOUT:
++		return io_timeout_prep(req, sqe, true);
++	case IORING_OP_ACCEPT:
++		return io_accept_prep(req, sqe);
++	case IORING_OP_FALLOCATE:
++		return io_fallocate_prep(req, sqe);
++	case IORING_OP_OPENAT:
++		return io_openat_prep(req, sqe);
++	case IORING_OP_CLOSE:
++		return io_close_prep(req, sqe);
++	case IORING_OP_FILES_UPDATE:
++		return io_rsrc_update_prep(req, sqe);
++	case IORING_OP_STATX:
++		return io_statx_prep(req, sqe);
++	case IORING_OP_FADVISE:
++		return io_fadvise_prep(req, sqe);
++	case IORING_OP_MADVISE:
++		return io_madvise_prep(req, sqe);
++	case IORING_OP_OPENAT2:
++		return io_openat2_prep(req, sqe);
++	case IORING_OP_EPOLL_CTL:
++		return io_epoll_ctl_prep(req, sqe);
++	case IORING_OP_SPLICE:
++		return io_splice_prep(req, sqe);
++	case IORING_OP_PROVIDE_BUFFERS:
++		return io_provide_buffers_prep(req, sqe);
++	case IORING_OP_REMOVE_BUFFERS:
++		return io_remove_buffers_prep(req, sqe);
++	case IORING_OP_TEE:
++		return io_tee_prep(req, sqe);
++	case IORING_OP_SHUTDOWN:
++		return io_shutdown_prep(req, sqe);
++	case IORING_OP_RENAMEAT:
++		return io_renameat_prep(req, sqe);
++	case IORING_OP_UNLINKAT:
++		return io_unlinkat_prep(req, sqe);
++	case IORING_OP_MKDIRAT:
++		return io_mkdirat_prep(req, sqe);
++	case IORING_OP_SYMLINKAT:
++		return io_symlinkat_prep(req, sqe);
++	case IORING_OP_LINKAT:
++		return io_linkat_prep(req, sqe);
++	}
++
++	printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
++			req->opcode);
++	return -EINVAL;
++}
++
++static int io_req_prep_async(struct io_kiocb *req)
++{
++	if (!io_op_defs[req->opcode].needs_async_setup)
++		return 0;
++	if (WARN_ON_ONCE(req->async_data))
++		return -EFAULT;
++	if (io_alloc_async_data(req))
++		return -EAGAIN;
++
++	switch (req->opcode) {
++	case IORING_OP_READV:
++		return io_rw_prep_async(req, READ);
++	case IORING_OP_WRITEV:
++		return io_rw_prep_async(req, WRITE);
++	case IORING_OP_SENDMSG:
++		return io_sendmsg_prep_async(req);
++	case IORING_OP_RECVMSG:
++		return io_recvmsg_prep_async(req);
++	case IORING_OP_CONNECT:
++		return io_connect_prep_async(req);
++	}
++	printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n",
++		    req->opcode);
++	return -EFAULT;
++}
++
++static u32 io_get_sequence(struct io_kiocb *req)
++{
++	u32 seq = req->ctx->cached_sq_head;
++
++	/* need original cached_sq_head, but it was increased for each req */
++	io_for_each_link(req, req)
++		seq--;
++	return seq;
++}
++
++static bool io_drain_req(struct io_kiocb *req)
++{
++	struct io_kiocb *pos;
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_defer_entry *de;
++	int ret;
++	u32 seq;
++
++	if (req->flags & REQ_F_FAIL) {
++		io_req_complete_fail_submit(req);
++		return true;
++	}
++
++	/*
++	 * If we need to drain a request in the middle of a link, drain the
++	 * head request and the next request/link after the current link.
++	 * Considering sequential execution of links, IOSQE_IO_DRAIN will be
++	 * maintained for every request of our link.
++	 */
++	if (ctx->drain_next) {
++		req->flags |= REQ_F_IO_DRAIN;
++		ctx->drain_next = false;
++	}
++	/* not interested in head, start from the first linked */
++	io_for_each_link(pos, req->link) {
++		if (pos->flags & REQ_F_IO_DRAIN) {
++			ctx->drain_next = true;
++			req->flags |= REQ_F_IO_DRAIN;
++			break;
++		}
++	}
++
++	/* Still need defer if there is pending req in defer list. */
++	spin_lock(&ctx->completion_lock);
++	if (likely(list_empty_careful(&ctx->defer_list) &&
++		!(req->flags & REQ_F_IO_DRAIN))) {
++		spin_unlock(&ctx->completion_lock);
++		ctx->drain_active = false;
++		return false;
++	}
++	spin_unlock(&ctx->completion_lock);
++
++	seq = io_get_sequence(req);
++	/* Still a chance to pass the sequence check */
++	if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
++		return false;
++
++	ret = io_req_prep_async(req);
++	if (ret)
++		goto fail;
++	io_prep_async_link(req);
++	de = kmalloc(sizeof(*de), GFP_KERNEL);
++	if (!de) {
++		ret = -ENOMEM;
++fail:
++		io_req_complete_failed(req, ret);
++		return true;
++	}
++
++	spin_lock(&ctx->completion_lock);
++	if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
++		spin_unlock(&ctx->completion_lock);
++		kfree(de);
++		io_queue_async_work(req, NULL);
++		return true;
++	}
++
++	trace_io_uring_defer(ctx, req, req->user_data);
++	de->req = req;
++	de->seq = seq;
++	list_add_tail(&de->list, &ctx->defer_list);
++	spin_unlock(&ctx->completion_lock);
++	return true;
++}
++
++static void io_clean_op(struct io_kiocb *req)
++{
++	if (req->flags & REQ_F_BUFFER_SELECTED) {
++		switch (req->opcode) {
++		case IORING_OP_READV:
++		case IORING_OP_READ_FIXED:
++		case IORING_OP_READ:
++			kfree((void *)(unsigned long)req->rw.addr);
++			break;
++		case IORING_OP_RECVMSG:
++		case IORING_OP_RECV:
++			kfree(req->sr_msg.kbuf);
++			break;
++		}
++	}
++
++	if (req->flags & REQ_F_NEED_CLEANUP) {
++		switch (req->opcode) {
++		case IORING_OP_READV:
++		case IORING_OP_READ_FIXED:
++		case IORING_OP_READ:
++		case IORING_OP_WRITEV:
++		case IORING_OP_WRITE_FIXED:
++		case IORING_OP_WRITE: {
++			struct io_async_rw *io = req->async_data;
++
++			kfree(io->free_iovec);
++			break;
++			}
++		case IORING_OP_RECVMSG:
++		case IORING_OP_SENDMSG: {
++			struct io_async_msghdr *io = req->async_data;
++
++			kfree(io->free_iov);
++			break;
++			}
++		case IORING_OP_OPENAT:
++		case IORING_OP_OPENAT2:
++			if (req->open.filename)
++				putname(req->open.filename);
++			break;
++		case IORING_OP_RENAMEAT:
++			putname(req->rename.oldpath);
++			putname(req->rename.newpath);
++			break;
++		case IORING_OP_UNLINKAT:
++			putname(req->unlink.filename);
++			break;
++		case IORING_OP_MKDIRAT:
++			putname(req->mkdir.filename);
++			break;
++		case IORING_OP_SYMLINKAT:
++			putname(req->symlink.oldpath);
++			putname(req->symlink.newpath);
++			break;
++		case IORING_OP_LINKAT:
++			putname(req->hardlink.oldpath);
++			putname(req->hardlink.newpath);
++			break;
++		}
++	}
++	if ((req->flags & REQ_F_POLLED) && req->apoll) {
++		kfree(req->apoll->double_poll);
++		kfree(req->apoll);
++		req->apoll = NULL;
++	}
++	if (req->flags & REQ_F_INFLIGHT) {
++		struct io_uring_task *tctx = req->task->io_uring;
++
++		atomic_dec(&tctx->inflight_tracked);
++	}
++	if (req->flags & REQ_F_CREDS)
++		put_cred(req->creds);
++
++	req->flags &= ~IO_REQ_CLEAN_FLAGS;
++}
++
++static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	const struct cred *creds = NULL;
++	int ret;
++
++	if ((req->flags & REQ_F_CREDS) && req->creds != current_cred())
++		creds = override_creds(req->creds);
++
++	switch (req->opcode) {
++	case IORING_OP_NOP:
++		ret = io_nop(req, issue_flags);
++		break;
++	case IORING_OP_READV:
++	case IORING_OP_READ_FIXED:
++	case IORING_OP_READ:
++		ret = io_read(req, issue_flags);
++		break;
++	case IORING_OP_WRITEV:
++	case IORING_OP_WRITE_FIXED:
++	case IORING_OP_WRITE:
++		ret = io_write(req, issue_flags);
++		break;
++	case IORING_OP_FSYNC:
++		ret = io_fsync(req, issue_flags);
++		break;
++	case IORING_OP_POLL_ADD:
++		ret = io_poll_add(req, issue_flags);
++		break;
++	case IORING_OP_POLL_REMOVE:
++		ret = io_poll_update(req, issue_flags);
++		break;
++	case IORING_OP_SYNC_FILE_RANGE:
++		ret = io_sync_file_range(req, issue_flags);
++		break;
++	case IORING_OP_SENDMSG:
++		ret = io_sendmsg(req, issue_flags);
++		break;
++	case IORING_OP_SEND:
++		ret = io_send(req, issue_flags);
++		break;
++	case IORING_OP_RECVMSG:
++		ret = io_recvmsg(req, issue_flags);
++		break;
++	case IORING_OP_RECV:
++		ret = io_recv(req, issue_flags);
++		break;
++	case IORING_OP_TIMEOUT:
++		ret = io_timeout(req, issue_flags);
++		break;
++	case IORING_OP_TIMEOUT_REMOVE:
++		ret = io_timeout_remove(req, issue_flags);
++		break;
++	case IORING_OP_ACCEPT:
++		ret = io_accept(req, issue_flags);
++		break;
++	case IORING_OP_CONNECT:
++		ret = io_connect(req, issue_flags);
++		break;
++	case IORING_OP_ASYNC_CANCEL:
++		ret = io_async_cancel(req, issue_flags);
++		break;
++	case IORING_OP_FALLOCATE:
++		ret = io_fallocate(req, issue_flags);
++		break;
++	case IORING_OP_OPENAT:
++		ret = io_openat(req, issue_flags);
++		break;
++	case IORING_OP_CLOSE:
++		ret = io_close(req, issue_flags);
++		break;
++	case IORING_OP_FILES_UPDATE:
++		ret = io_files_update(req, issue_flags);
++		break;
++	case IORING_OP_STATX:
++		ret = io_statx(req, issue_flags);
++		break;
++	case IORING_OP_FADVISE:
++		ret = io_fadvise(req, issue_flags);
++		break;
++	case IORING_OP_MADVISE:
++		ret = io_madvise(req, issue_flags);
++		break;
++	case IORING_OP_OPENAT2:
++		ret = io_openat2(req, issue_flags);
++		break;
++	case IORING_OP_EPOLL_CTL:
++		ret = io_epoll_ctl(req, issue_flags);
++		break;
++	case IORING_OP_SPLICE:
++		ret = io_splice(req, issue_flags);
++		break;
++	case IORING_OP_PROVIDE_BUFFERS:
++		ret = io_provide_buffers(req, issue_flags);
++		break;
++	case IORING_OP_REMOVE_BUFFERS:
++		ret = io_remove_buffers(req, issue_flags);
++		break;
++	case IORING_OP_TEE:
++		ret = io_tee(req, issue_flags);
++		break;
++	case IORING_OP_SHUTDOWN:
++		ret = io_shutdown(req, issue_flags);
++		break;
++	case IORING_OP_RENAMEAT:
++		ret = io_renameat(req, issue_flags);
++		break;
++	case IORING_OP_UNLINKAT:
++		ret = io_unlinkat(req, issue_flags);
++		break;
++	case IORING_OP_MKDIRAT:
++		ret = io_mkdirat(req, issue_flags);
++		break;
++	case IORING_OP_SYMLINKAT:
++		ret = io_symlinkat(req, issue_flags);
++		break;
++	case IORING_OP_LINKAT:
++		ret = io_linkat(req, issue_flags);
++		break;
++	default:
++		ret = -EINVAL;
++		break;
++	}
++
++	if (creds)
++		revert_creds(creds);
++	if (ret)
++		return ret;
++	/* If the op doesn't have a file, we're not polling for it */
++	if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file)
++		io_iopoll_req_issued(req);
++
++	return 0;
++}
++
++static struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
++{
++	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
++
++	req = io_put_req_find_next(req);
++	return req ? &req->work : NULL;
++}
++
++static void io_wq_submit_work(struct io_wq_work *work)
++{
++	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
++	struct io_kiocb *timeout;
++	int ret = 0;
++
++	/* one will be dropped by ->io_free_work() after returning to io-wq */
++	if (!(req->flags & REQ_F_REFCOUNT))
++		__io_req_set_refcount(req, 2);
++	else
++		req_ref_get(req);
++
++	timeout = io_prep_linked_timeout(req);
++	if (timeout)
++		io_queue_linked_timeout(timeout);
++
++	/* either cancelled or io-wq is dying, so don't touch tctx->iowq */
++	if (work->flags & IO_WQ_WORK_CANCEL)
++		ret = -ECANCELED;
++
++	if (!ret) {
++		do {
++			ret = io_issue_sqe(req, 0);
++			/*
++			 * We can get EAGAIN for polled IO even though we're
++			 * forcing a sync submission from here, since we can't
++			 * wait for request slots on the block side.
++			 */
++			if (ret != -EAGAIN || !(req->ctx->flags & IORING_SETUP_IOPOLL))
++				break;
++			cond_resched();
++		} while (1);
++	}
++
++	/* avoid locking problems by failing it from a clean context */
++	if (ret)
++		io_req_task_queue_fail(req, ret);
++}
++
++static inline struct io_fixed_file *io_fixed_file_slot(struct io_file_table *table,
++						       unsigned i)
++{
++	return &table->files[i];
++}
++
++static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
++					      int index)
++{
++	struct io_fixed_file *slot = io_fixed_file_slot(&ctx->file_table, index);
++
++	return (struct file *) (slot->file_ptr & FFS_MASK);
++}
++
++static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file)
++{
++	unsigned long file_ptr = (unsigned long) file;
++
++	if (__io_file_supports_nowait(file, READ))
++		file_ptr |= FFS_ASYNC_READ;
++	if (__io_file_supports_nowait(file, WRITE))
++		file_ptr |= FFS_ASYNC_WRITE;
++	if (S_ISREG(file_inode(file)->i_mode))
++		file_ptr |= FFS_ISREG;
++	file_slot->file_ptr = file_ptr;
++}
++
++static inline struct file *io_file_get_fixed(struct io_ring_ctx *ctx,
++					     struct io_kiocb *req, int fd)
++{
++	struct file *file;
++	unsigned long file_ptr;
++
++	if (unlikely((unsigned int)fd >= ctx->nr_user_files))
++		return NULL;
++	fd = array_index_nospec(fd, ctx->nr_user_files);
++	file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr;
++	file = (struct file *) (file_ptr & FFS_MASK);
++	file_ptr &= ~FFS_MASK;
++	/* mask in overlapping REQ_F and FFS bits */
++	req->flags |= (file_ptr << REQ_F_NOWAIT_READ_BIT);
++	io_req_set_rsrc_node(req);
++	return file;
++}
++
++static struct file *io_file_get_normal(struct io_ring_ctx *ctx,
++				       struct io_kiocb *req, int fd)
++{
++	struct file *file = fget(fd);
++
++	trace_io_uring_file_get(ctx, fd);
++
++	/* we don't allow fixed io_uring files */
++	if (file && unlikely(file->f_op == &io_uring_fops))
++		io_req_track_inflight(req);
++	return file;
++}
++
++static inline struct file *io_file_get(struct io_ring_ctx *ctx,
++				       struct io_kiocb *req, int fd, bool fixed)
++{
++	if (fixed)
++		return io_file_get_fixed(ctx, req, fd);
++	else
++		return io_file_get_normal(ctx, req, fd);
++}
++
++static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked)
++{
++	struct io_kiocb *prev = req->timeout.prev;
++	int ret = -ENOENT;
++
++	if (prev) {
++		if (!(req->task->flags & PF_EXITING))
++			ret = io_try_cancel_userdata(req, prev->user_data);
++		io_req_complete_post(req, ret ?: -ETIME, 0);
++		io_put_req(prev);
++	} else {
++		io_req_complete_post(req, -ETIME, 0);
++	}
++}
++
++static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
++{
++	struct io_timeout_data *data = container_of(timer,
++						struct io_timeout_data, timer);
++	struct io_kiocb *prev, *req = data->req;
++	struct io_ring_ctx *ctx = req->ctx;
++	unsigned long flags;
++
++	spin_lock_irqsave(&ctx->timeout_lock, flags);
++	prev = req->timeout.head;
++	req->timeout.head = NULL;
++
++	/*
++	 * We don't expect the list to be empty, that will only happen if we
++	 * race with the completion of the linked work.
++	 */
++	if (prev) {
++		io_remove_next_linked(prev);
++		if (!req_ref_inc_not_zero(prev))
++			prev = NULL;
++	}
++	list_del(&req->timeout.list);
++	req->timeout.prev = prev;
++	spin_unlock_irqrestore(&ctx->timeout_lock, flags);
++
++	req->io_task_work.func = io_req_task_link_timeout;
++	io_req_task_work_add(req);
++	return HRTIMER_NORESTART;
++}
++
++static void io_queue_linked_timeout(struct io_kiocb *req)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++
++	spin_lock_irq(&ctx->timeout_lock);
++	/*
++	 * If the back reference is NULL, then our linked request finished
++	 * before we got a chance to setup the timer
++	 */
++	if (req->timeout.head) {
++		struct io_timeout_data *data = req->async_data;
++
++		data->timer.function = io_link_timeout_fn;
++		hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
++				data->mode);
++		list_add_tail(&req->timeout.list, &ctx->ltimeout_list);
++	}
++	spin_unlock_irq(&ctx->timeout_lock);
++	/* drop submission reference */
++	io_put_req(req);
++}
++
++static void __io_queue_sqe(struct io_kiocb *req)
++	__must_hold(&req->ctx->uring_lock)
++{
++	struct io_kiocb *linked_timeout;
++	int ret;
++
++issue_sqe:
++	ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
++
++	/*
++	 * We async punt it if the file wasn't marked NOWAIT, or if the file
++	 * doesn't support non-blocking read/write attempts
++	 */
++	if (likely(!ret)) {
++		if (req->flags & REQ_F_COMPLETE_INLINE) {
++			struct io_ring_ctx *ctx = req->ctx;
++			struct io_submit_state *state = &ctx->submit_state;
++
++			state->compl_reqs[state->compl_nr++] = req;
++			if (state->compl_nr == ARRAY_SIZE(state->compl_reqs))
++				io_submit_flush_completions(ctx);
++			return;
++		}
++
++		linked_timeout = io_prep_linked_timeout(req);
++		if (linked_timeout)
++			io_queue_linked_timeout(linked_timeout);
++	} else if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
++		linked_timeout = io_prep_linked_timeout(req);
++
++		switch (io_arm_poll_handler(req)) {
++		case IO_APOLL_READY:
++			if (linked_timeout)
++				io_queue_linked_timeout(linked_timeout);
++			goto issue_sqe;
++		case IO_APOLL_ABORTED:
++			/*
++			 * Queued up for async execution, worker will release
++			 * submit reference when the iocb is actually submitted.
++			 */
++			io_queue_async_work(req, NULL);
++			break;
++		}
++
++		if (linked_timeout)
++			io_queue_linked_timeout(linked_timeout);
++	} else {
++		io_req_complete_failed(req, ret);
++	}
++}
++
++static inline void io_queue_sqe(struct io_kiocb *req)
++	__must_hold(&req->ctx->uring_lock)
++{
++	if (unlikely(req->ctx->drain_active) && io_drain_req(req))
++		return;
++
++	if (likely(!(req->flags & (REQ_F_FORCE_ASYNC | REQ_F_FAIL)))) {
++		__io_queue_sqe(req);
++	} else if (req->flags & REQ_F_FAIL) {
++		io_req_complete_fail_submit(req);
++	} else {
++		int ret = io_req_prep_async(req);
++
++		if (unlikely(ret))
++			io_req_complete_failed(req, ret);
++		else
++			io_queue_async_work(req, NULL);
++	}
++}
++
++/*
++ * Check SQE restrictions (opcode and flags).
++ *
++ * Returns 'true' if SQE is allowed, 'false' otherwise.
++ */
++static inline bool io_check_restriction(struct io_ring_ctx *ctx,
++					struct io_kiocb *req,
++					unsigned int sqe_flags)
++{
++	if (likely(!ctx->restricted))
++		return true;
++
++	if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
++		return false;
++
++	if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
++	    ctx->restrictions.sqe_flags_required)
++		return false;
++
++	if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
++			  ctx->restrictions.sqe_flags_required))
++		return false;
++
++	return true;
++}
++
++static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
++		       const struct io_uring_sqe *sqe)
++	__must_hold(&ctx->uring_lock)
++{
++	struct io_submit_state *state;
++	unsigned int sqe_flags;
++	int personality, ret = 0;
++
++	/* req is partially pre-initialised, see io_preinit_req() */
++	req->opcode = READ_ONCE(sqe->opcode);
++	/* same numerical values with corresponding REQ_F_*, safe to copy */
++	req->flags = sqe_flags = READ_ONCE(sqe->flags);
++	req->user_data = READ_ONCE(sqe->user_data);
++	req->file = NULL;
++	req->fixed_rsrc_refs = NULL;
++	req->task = current;
++
++	/* enforce forwards compatibility on users */
++	if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))
++		return -EINVAL;
++	if (unlikely(req->opcode >= IORING_OP_LAST))
++		return -EINVAL;
++	if (!io_check_restriction(ctx, req, sqe_flags))
++		return -EACCES;
++
++	if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
++	    !io_op_defs[req->opcode].buffer_select)
++		return -EOPNOTSUPP;
++	if (unlikely(sqe_flags & IOSQE_IO_DRAIN))
++		ctx->drain_active = true;
++
++	personality = READ_ONCE(sqe->personality);
++	if (personality) {
++		req->creds = xa_load(&ctx->personalities, personality);
++		if (!req->creds)
++			return -EINVAL;
++		get_cred(req->creds);
++		req->flags |= REQ_F_CREDS;
++	}
++	state = &ctx->submit_state;
++
++	/*
++	 * Plug now if we have more than 1 IO left after this, and the target
++	 * is potentially a read/write to block based storage.
++	 */
++	if (!state->plug_started && state->ios_left > 1 &&
++	    io_op_defs[req->opcode].plug) {
++		blk_start_plug(&state->plug);
++		state->plug_started = true;
++	}
++
++	if (io_op_defs[req->opcode].needs_file) {
++		req->file = io_file_get(ctx, req, READ_ONCE(sqe->fd),
++					(sqe_flags & IOSQE_FIXED_FILE));
++		if (unlikely(!req->file))
++			ret = -EBADF;
++	}
++
++	state->ios_left--;
++	return ret;
++}
++
++static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
++			 const struct io_uring_sqe *sqe)
++	__must_hold(&ctx->uring_lock)
++{
++	struct io_submit_link *link = &ctx->submit_state.link;
++	int ret;
++
++	ret = io_init_req(ctx, req, sqe);
++	if (unlikely(ret)) {
++fail_req:
++		/* fail even hard links since we don't submit */
++		if (link->head) {
++			/*
++			 * we can judge a link req is failed or cancelled by if
++			 * REQ_F_FAIL is set, but the head is an exception since
++			 * it may be set REQ_F_FAIL because of other req's failure
++			 * so let's leverage req->result to distinguish if a head
++			 * is set REQ_F_FAIL because of its failure or other req's
++			 * failure so that we can set the correct ret code for it.
++			 * init result here to avoid affecting the normal path.
++			 */
++			if (!(link->head->flags & REQ_F_FAIL))
++				req_fail_link_node(link->head, -ECANCELED);
++		} else if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
++			/*
++			 * the current req is a normal req, we should return
++			 * error and thus break the submittion loop.
++			 */
++			io_req_complete_failed(req, ret);
++			return ret;
++		}
++		req_fail_link_node(req, ret);
++	} else {
++		ret = io_req_prep(req, sqe);
++		if (unlikely(ret))
++			goto fail_req;
++	}
++
++	/* don't need @sqe from now on */
++	trace_io_uring_submit_sqe(ctx, req, req->opcode, req->user_data,
++				  req->flags, true,
++				  ctx->flags & IORING_SETUP_SQPOLL);
++
++	/*
++	 * If we already have a head request, queue this one for async
++	 * submittal once the head completes. If we don't have a head but
++	 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
++	 * submitted sync once the chain is complete. If none of those
++	 * conditions are true (normal request), then just queue it.
++	 */
++	if (link->head) {
++		struct io_kiocb *head = link->head;
++
++		if (!(req->flags & REQ_F_FAIL)) {
++			ret = io_req_prep_async(req);
++			if (unlikely(ret)) {
++				req_fail_link_node(req, ret);
++				if (!(head->flags & REQ_F_FAIL))
++					req_fail_link_node(head, -ECANCELED);
++			}
++		}
++		trace_io_uring_link(ctx, req, head);
++		link->last->link = req;
++		link->last = req;
++
++		/* last request of a link, enqueue the link */
++		if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
++			link->head = NULL;
++			io_queue_sqe(head);
++		}
++	} else {
++		if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
++			link->head = req;
++			link->last = req;
++		} else {
++			io_queue_sqe(req);
++		}
++	}
++
++	return 0;
++}
++
++/*
++ * Batched submission is done, ensure local IO is flushed out.
++ */
++static void io_submit_state_end(struct io_submit_state *state,
++				struct io_ring_ctx *ctx)
++{
++	if (state->link.head)
++		io_queue_sqe(state->link.head);
++	if (state->compl_nr)
++		io_submit_flush_completions(ctx);
++	if (state->plug_started)
++		blk_finish_plug(&state->plug);
++}
++
++/*
++ * Start submission side cache.
++ */
++static void io_submit_state_start(struct io_submit_state *state,
++				  unsigned int max_ios)
++{
++	state->plug_started = false;
++	state->ios_left = max_ios;
++	/* set only head, no need to init link_last in advance */
++	state->link.head = NULL;
++}
++
++static void io_commit_sqring(struct io_ring_ctx *ctx)
++{
++	struct io_rings *rings = ctx->rings;
++
++	/*
++	 * Ensure any loads from the SQEs are done at this point,
++	 * since once we write the new head, the application could
++	 * write new data to them.
++	 */
++	smp_store_release(&rings->sq.head, ctx->cached_sq_head);
++}
++
++/*
++ * Fetch an sqe, if one is available. Note this returns a pointer to memory
++ * that is mapped by userspace. This means that care needs to be taken to
++ * ensure that reads are stable, as we cannot rely on userspace always
++ * being a good citizen. If members of the sqe are validated and then later
++ * used, it's important that those reads are done through READ_ONCE() to
++ * prevent a re-load down the line.
++ */
++static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
++{
++	unsigned head, mask = ctx->sq_entries - 1;
++	unsigned sq_idx = ctx->cached_sq_head++ & mask;
++
++	/*
++	 * The cached sq head (or cq tail) serves two purposes:
++	 *
++	 * 1) allows us to batch the cost of updating the user visible
++	 *    head updates.
++	 * 2) allows the kernel side to track the head on its own, even
++	 *    though the application is the one updating it.
++	 */
++	head = READ_ONCE(ctx->sq_array[sq_idx]);
++	if (likely(head < ctx->sq_entries))
++		return &ctx->sq_sqes[head];
++
++	/* drop invalid entries */
++	ctx->cq_extra--;
++	WRITE_ONCE(ctx->rings->sq_dropped,
++		   READ_ONCE(ctx->rings->sq_dropped) + 1);
++	return NULL;
++}
++
++static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
++	__must_hold(&ctx->uring_lock)
++{
++	int submitted = 0;
++
++	/* make sure SQ entry isn't read before tail */
++	nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
++	if (!percpu_ref_tryget_many(&ctx->refs, nr))
++		return -EAGAIN;
++	io_get_task_refs(nr);
++
++	io_submit_state_start(&ctx->submit_state, nr);
++	while (submitted < nr) {
++		const struct io_uring_sqe *sqe;
++		struct io_kiocb *req;
++
++		req = io_alloc_req(ctx);
++		if (unlikely(!req)) {
++			if (!submitted)
++				submitted = -EAGAIN;
++			break;
++		}
++		sqe = io_get_sqe(ctx);
++		if (unlikely(!sqe)) {
++			list_add(&req->inflight_entry, &ctx->submit_state.free_list);
++			break;
++		}
++		/* will complete beyond this point, count as submitted */
++		submitted++;
++		if (io_submit_sqe(ctx, req, sqe))
++			break;
++	}
++
++	if (unlikely(submitted != nr)) {
++		int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
++		int unused = nr - ref_used;
++
++		current->io_uring->cached_refs += unused;
++		percpu_ref_put_many(&ctx->refs, unused);
++	}
++
++	io_submit_state_end(&ctx->submit_state, ctx);
++	 /* Commit SQ ring head once we've consumed and submitted all SQEs */
++	io_commit_sqring(ctx);
++
++	return submitted;
++}
++
++static inline bool io_sqd_events_pending(struct io_sq_data *sqd)
++{
++	return READ_ONCE(sqd->state);
++}
++
++static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
++{
++	/* Tell userspace we may need a wakeup call */
++	spin_lock(&ctx->completion_lock);
++	WRITE_ONCE(ctx->rings->sq_flags,
++		   ctx->rings->sq_flags | IORING_SQ_NEED_WAKEUP);
++	spin_unlock(&ctx->completion_lock);
++}
++
++static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
++{
++	spin_lock(&ctx->completion_lock);
++	WRITE_ONCE(ctx->rings->sq_flags,
++		   ctx->rings->sq_flags & ~IORING_SQ_NEED_WAKEUP);
++	spin_unlock(&ctx->completion_lock);
++}
++
++static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
++{
++	unsigned int to_submit;
++	int ret = 0;
++
++	to_submit = io_sqring_entries(ctx);
++	/* if we're handling multiple rings, cap submit size for fairness */
++	if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE)
++		to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;
++
++	if (!list_empty(&ctx->iopoll_list) || to_submit) {
++		unsigned nr_events = 0;
++		const struct cred *creds = NULL;
++
++		if (ctx->sq_creds != current_cred())
++			creds = override_creds(ctx->sq_creds);
++
++		mutex_lock(&ctx->uring_lock);
++		if (!list_empty(&ctx->iopoll_list))
++			io_do_iopoll(ctx, &nr_events, 0);
++
++		/*
++		 * Don't submit if refs are dying, good for io_uring_register(),
++		 * but also it is relied upon by io_ring_exit_work()
++		 */
++		if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
++		    !(ctx->flags & IORING_SETUP_R_DISABLED))
++			ret = io_submit_sqes(ctx, to_submit);
++		mutex_unlock(&ctx->uring_lock);
++
++		if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
++			wake_up(&ctx->sqo_sq_wait);
++		if (creds)
++			revert_creds(creds);
++	}
++
++	return ret;
++}
++
++static void io_sqd_update_thread_idle(struct io_sq_data *sqd)
++{
++	struct io_ring_ctx *ctx;
++	unsigned sq_thread_idle = 0;
++
++	list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
++		sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle);
++	sqd->sq_thread_idle = sq_thread_idle;
++}
++
++static bool io_sqd_handle_event(struct io_sq_data *sqd)
++{
++	bool did_sig = false;
++	struct ksignal ksig;
++
++	if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
++	    signal_pending(current)) {
++		mutex_unlock(&sqd->lock);
++		if (signal_pending(current))
++			did_sig = get_signal(&ksig);
++		cond_resched();
++		mutex_lock(&sqd->lock);
++	}
++	return did_sig || test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
++}
++
++static int io_sq_thread(void *data)
++{
++	struct io_sq_data *sqd = data;
++	struct io_ring_ctx *ctx;
++	unsigned long timeout = 0;
++	char buf[TASK_COMM_LEN];
++	DEFINE_WAIT(wait);
++
++	snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
++	set_task_comm(current, buf);
++
++	if (sqd->sq_cpu != -1)
++		set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
++	else
++		set_cpus_allowed_ptr(current, cpu_online_mask);
++	current->flags |= PF_NO_SETAFFINITY;
++
++	mutex_lock(&sqd->lock);
++	while (1) {
++		bool cap_entries, sqt_spin = false;
++
++		if (io_sqd_events_pending(sqd) || signal_pending(current)) {
++			if (io_sqd_handle_event(sqd))
++				break;
++			timeout = jiffies + sqd->sq_thread_idle;
++		}
++
++		cap_entries = !list_is_singular(&sqd->ctx_list);
++		list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
++			int ret = __io_sq_thread(ctx, cap_entries);
++
++			if (!sqt_spin && (ret > 0 || !list_empty(&ctx->iopoll_list)))
++				sqt_spin = true;
++		}
++		if (io_run_task_work())
++			sqt_spin = true;
++
++		if (sqt_spin || !time_after(jiffies, timeout)) {
++			cond_resched();
++			if (sqt_spin)
++				timeout = jiffies + sqd->sq_thread_idle;
++			continue;
++		}
++
++		prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
++		if (!io_sqd_events_pending(sqd) && !current->task_works) {
++			bool needs_sched = true;
++
++			list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
++				io_ring_set_wakeup_flag(ctx);
++
++				if ((ctx->flags & IORING_SETUP_IOPOLL) &&
++				    !list_empty_careful(&ctx->iopoll_list)) {
++					needs_sched = false;
++					break;
++				}
++				if (io_sqring_entries(ctx)) {
++					needs_sched = false;
++					break;
++				}
++			}
++
++			if (needs_sched) {
++				mutex_unlock(&sqd->lock);
++				schedule();
++				mutex_lock(&sqd->lock);
++			}
++			list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
++				io_ring_clear_wakeup_flag(ctx);
++		}
++
++		finish_wait(&sqd->wait, &wait);
++		timeout = jiffies + sqd->sq_thread_idle;
++	}
++
++	io_uring_cancel_generic(true, sqd);
++	sqd->thread = NULL;
++	list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
++		io_ring_set_wakeup_flag(ctx);
++	io_run_task_work();
++	mutex_unlock(&sqd->lock);
++
++	complete(&sqd->exited);
++	do_exit(0);
++}
++
++struct io_wait_queue {
++	struct wait_queue_entry wq;
++	struct io_ring_ctx *ctx;
++	unsigned cq_tail;
++	unsigned nr_timeouts;
++};
++
++static inline bool io_should_wake(struct io_wait_queue *iowq)
++{
++	struct io_ring_ctx *ctx = iowq->ctx;
++	int dist = ctx->cached_cq_tail - (int) iowq->cq_tail;
++
++	/*
++	 * Wake up if we have enough events, or if a timeout occurred since we
++	 * started waiting. For timeouts, we always want to return to userspace,
++	 * regardless of event count.
++	 */
++	return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
++}
++
++static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
++			    int wake_flags, void *key)
++{
++	struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
++							wq);
++
++	/*
++	 * Cannot safely flush overflowed CQEs from here, ensure we wake up
++	 * the task, and the next invocation will do it.
++	 */
++	if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->check_cq_overflow))
++		return autoremove_wake_function(curr, mode, wake_flags, key);
++	return -1;
++}
++
++static int io_run_task_work_sig(void)
++{
++	if (io_run_task_work())
++		return 1;
++	if (!signal_pending(current))
++		return 0;
++	if (test_thread_flag(TIF_NOTIFY_SIGNAL))
++		return -ERESTARTSYS;
++	return -EINTR;
++}
++
++/* when returns >0, the caller should retry */
++static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
++					  struct io_wait_queue *iowq,
++					  ktime_t timeout)
++{
++	int ret;
++
++	/* make sure we run task_work before checking for signals */
++	ret = io_run_task_work_sig();
++	if (ret || io_should_wake(iowq))
++		return ret;
++	/* let the caller flush overflows, retry */
++	if (test_bit(0, &ctx->check_cq_overflow))
++		return 1;
++
++	if (!schedule_hrtimeout(&timeout, HRTIMER_MODE_ABS))
++		return -ETIME;
++	return 1;
++}
++
++/*
++ * Wait until events become available, if we don't already have some. The
++ * application must reap them itself, as they reside on the shared cq ring.
++ */
++static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
++			  const sigset_t __user *sig, size_t sigsz,
++			  struct __kernel_timespec __user *uts)
++{
++	struct io_wait_queue iowq;
++	struct io_rings *rings = ctx->rings;
++	ktime_t timeout = KTIME_MAX;
++	int ret;
++
++	do {
++		io_cqring_overflow_flush(ctx);
++		if (io_cqring_events(ctx) >= min_events)
++			return 0;
++		if (!io_run_task_work())
++			break;
++	} while (1);
++
++	if (uts) {
++		struct timespec64 ts;
++
++		if (get_timespec64(&ts, uts))
++			return -EFAULT;
++		timeout = ktime_add_ns(timespec64_to_ktime(ts), ktime_get_ns());
++	}
++
++	if (sig) {
++#ifdef CONFIG_COMPAT
++		if (in_compat_syscall())
++			ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
++						      sigsz);
++		else
++#endif
++			ret = set_user_sigmask(sig, sigsz);
++
++		if (ret)
++			return ret;
++	}
++
++	init_waitqueue_func_entry(&iowq.wq, io_wake_function);
++	iowq.wq.private = current;
++	INIT_LIST_HEAD(&iowq.wq.entry);
++	iowq.ctx = ctx;
++	iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
++	iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events;
++
++	trace_io_uring_cqring_wait(ctx, min_events);
++	do {
++		/* if we can't even flush overflow, don't wait for more */
++		if (!io_cqring_overflow_flush(ctx)) {
++			ret = -EBUSY;
++			break;
++		}
++		prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq,
++						TASK_INTERRUPTIBLE);
++		ret = io_cqring_wait_schedule(ctx, &iowq, timeout);
++		finish_wait(&ctx->cq_wait, &iowq.wq);
++		cond_resched();
++	} while (ret > 0);
++
++	restore_saved_sigmask_unless(ret == -EINTR);
++
++	return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
++}
++
++static void io_free_page_table(void **table, size_t size)
++{
++	unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
++
++	for (i = 0; i < nr_tables; i++)
++		kfree(table[i]);
++	kfree(table);
++}
++
++static void **io_alloc_page_table(size_t size)
++{
++	unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
++	size_t init_size = size;
++	void **table;
++
++	table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT);
++	if (!table)
++		return NULL;
++
++	for (i = 0; i < nr_tables; i++) {
++		unsigned int this_size = min_t(size_t, size, PAGE_SIZE);
++
++		table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT);
++		if (!table[i]) {
++			io_free_page_table(table, init_size);
++			return NULL;
++		}
++		size -= this_size;
++	}
++	return table;
++}
++
++static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node)
++{
++	percpu_ref_exit(&ref_node->refs);
++	kfree(ref_node);
++}
++
++static void io_rsrc_node_ref_zero(struct percpu_ref *ref)
++{
++	struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs);
++	struct io_ring_ctx *ctx = node->rsrc_data->ctx;
++	unsigned long flags;
++	bool first_add = false;
++	unsigned long delay = HZ;
++
++	spin_lock_irqsave(&ctx->rsrc_ref_lock, flags);
++	node->done = true;
++
++	/* if we are mid-quiesce then do not delay */
++	if (node->rsrc_data->quiesce)
++		delay = 0;
++
++	while (!list_empty(&ctx->rsrc_ref_list)) {
++		node = list_first_entry(&ctx->rsrc_ref_list,
++					    struct io_rsrc_node, node);
++		/* recycle ref nodes in order */
++		if (!node->done)
++			break;
++		list_del(&node->node);
++		first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist);
++	}
++	spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags);
++
++	if (first_add)
++		mod_delayed_work(system_wq, &ctx->rsrc_put_work, delay);
++}
++
++static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx)
++{
++	struct io_rsrc_node *ref_node;
++
++	ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
++	if (!ref_node)
++		return NULL;
++
++	if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
++			    0, GFP_KERNEL)) {
++		kfree(ref_node);
++		return NULL;
++	}
++	INIT_LIST_HEAD(&ref_node->node);
++	INIT_LIST_HEAD(&ref_node->rsrc_list);
++	ref_node->done = false;
++	return ref_node;
++}
++
++static void io_rsrc_node_switch(struct io_ring_ctx *ctx,
++				struct io_rsrc_data *data_to_kill)
++{
++	WARN_ON_ONCE(!ctx->rsrc_backup_node);
++	WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node);
++
++	if (data_to_kill) {
++		struct io_rsrc_node *rsrc_node = ctx->rsrc_node;
++
++		rsrc_node->rsrc_data = data_to_kill;
++		spin_lock_irq(&ctx->rsrc_ref_lock);
++		list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list);
++		spin_unlock_irq(&ctx->rsrc_ref_lock);
++
++		atomic_inc(&data_to_kill->refs);
++		percpu_ref_kill(&rsrc_node->refs);
++		ctx->rsrc_node = NULL;
++	}
++
++	if (!ctx->rsrc_node) {
++		ctx->rsrc_node = ctx->rsrc_backup_node;
++		ctx->rsrc_backup_node = NULL;
++	}
++}
++
++static int io_rsrc_node_switch_start(struct io_ring_ctx *ctx)
++{
++	if (ctx->rsrc_backup_node)
++		return 0;
++	ctx->rsrc_backup_node = io_rsrc_node_alloc(ctx);
++	return ctx->rsrc_backup_node ? 0 : -ENOMEM;
++}
++
++static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, struct io_ring_ctx *ctx)
++{
++	int ret;
++
++	/* As we may drop ->uring_lock, other task may have started quiesce */
++	if (data->quiesce)
++		return -ENXIO;
++
++	data->quiesce = true;
++	do {
++		ret = io_rsrc_node_switch_start(ctx);
++		if (ret)
++			break;
++		io_rsrc_node_switch(ctx, data);
++
++		/* kill initial ref, already quiesced if zero */
++		if (atomic_dec_and_test(&data->refs))
++			break;
++		mutex_unlock(&ctx->uring_lock);
++		flush_delayed_work(&ctx->rsrc_put_work);
++		ret = wait_for_completion_interruptible(&data->done);
++		if (!ret) {
++			mutex_lock(&ctx->uring_lock);
++			if (atomic_read(&data->refs) > 0) {
++				/*
++				 * it has been revived by another thread while
++				 * we were unlocked
++				 */
++				mutex_unlock(&ctx->uring_lock);
++			} else {
++				break;
++			}
++		}
++
++		atomic_inc(&data->refs);
++		/* wait for all works potentially completing data->done */
++		flush_delayed_work(&ctx->rsrc_put_work);
++		reinit_completion(&data->done);
++
++		ret = io_run_task_work_sig();
++		mutex_lock(&ctx->uring_lock);
++	} while (ret >= 0);
++	data->quiesce = false;
++
++	return ret;
++}
++
++static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
++{
++	unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
++	unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
++
++	return &data->tags[table_idx][off];
++}
++
++static void io_rsrc_data_free(struct io_rsrc_data *data)
++{
++	size_t size = data->nr * sizeof(data->tags[0][0]);
++
++	if (data->tags)
++		io_free_page_table((void **)data->tags, size);
++	kfree(data);
++}
++
++static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put,
++			      u64 __user *utags, unsigned nr,
++			      struct io_rsrc_data **pdata)
++{
++	struct io_rsrc_data *data;
++	int ret = -ENOMEM;
++	unsigned i;
++
++	data = kzalloc(sizeof(*data), GFP_KERNEL);
++	if (!data)
++		return -ENOMEM;
++	data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0]));
++	if (!data->tags) {
++		kfree(data);
++		return -ENOMEM;
++	}
++
++	data->nr = nr;
++	data->ctx = ctx;
++	data->do_put = do_put;
++	if (utags) {
++		ret = -EFAULT;
++		for (i = 0; i < nr; i++) {
++			u64 *tag_slot = io_get_tag_slot(data, i);
++
++			if (copy_from_user(tag_slot, &utags[i],
++					   sizeof(*tag_slot)))
++				goto fail;
++		}
++	}
++
++	atomic_set(&data->refs, 1);
++	init_completion(&data->done);
++	*pdata = data;
++	return 0;
++fail:
++	io_rsrc_data_free(data);
++	return ret;
++}
++
++static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
++{
++	table->files = kvcalloc(nr_files, sizeof(table->files[0]),
++				GFP_KERNEL_ACCOUNT);
++	return !!table->files;
++}
++
++static void io_free_file_tables(struct io_file_table *table)
++{
++	kvfree(table->files);
++	table->files = NULL;
++}
++
++static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
++{
++#if defined(CONFIG_UNIX)
++	if (ctx->ring_sock) {
++		struct sock *sock = ctx->ring_sock->sk;
++		struct sk_buff *skb;
++
++		while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
++			kfree_skb(skb);
++	}
++#else
++	int i;
++
++	for (i = 0; i < ctx->nr_user_files; i++) {
++		struct file *file;
++
++		file = io_file_from_index(ctx, i);
++		if (file)
++			fput(file);
++	}
++#endif
++	io_free_file_tables(&ctx->file_table);
++	io_rsrc_data_free(ctx->file_data);
++	ctx->file_data = NULL;
++	ctx->nr_user_files = 0;
++}
++
++static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
++{
++	unsigned nr = ctx->nr_user_files;
++	int ret;
++
++	if (!ctx->file_data)
++		return -ENXIO;
++
++	/*
++	 * Quiesce may unlock ->uring_lock, and while it's not held
++	 * prevent new requests using the table.
++	 */
++	ctx->nr_user_files = 0;
++	ret = io_rsrc_ref_quiesce(ctx->file_data, ctx);
++	ctx->nr_user_files = nr;
++	if (!ret)
++		__io_sqe_files_unregister(ctx);
++	return ret;
++}
++
++static void io_sq_thread_unpark(struct io_sq_data *sqd)
++	__releases(&sqd->lock)
++{
++	WARN_ON_ONCE(sqd->thread == current);
++
++	/*
++	 * Do the dance but not conditional clear_bit() because it'd race with
++	 * other threads incrementing park_pending and setting the bit.
++	 */
++	clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
++	if (atomic_dec_return(&sqd->park_pending))
++		set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
++	mutex_unlock(&sqd->lock);
++}
++
++static void io_sq_thread_park(struct io_sq_data *sqd)
++	__acquires(&sqd->lock)
++{
++	WARN_ON_ONCE(sqd->thread == current);
++
++	atomic_inc(&sqd->park_pending);
++	set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
++	mutex_lock(&sqd->lock);
++	if (sqd->thread)
++		wake_up_process(sqd->thread);
++}
++
++static void io_sq_thread_stop(struct io_sq_data *sqd)
++{
++	WARN_ON_ONCE(sqd->thread == current);
++	WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state));
++
++	set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
++	mutex_lock(&sqd->lock);
++	if (sqd->thread)
++		wake_up_process(sqd->thread);
++	mutex_unlock(&sqd->lock);
++	wait_for_completion(&sqd->exited);
++}
++
++static void io_put_sq_data(struct io_sq_data *sqd)
++{
++	if (refcount_dec_and_test(&sqd->refs)) {
++		WARN_ON_ONCE(atomic_read(&sqd->park_pending));
++
++		io_sq_thread_stop(sqd);
++		kfree(sqd);
++	}
++}
++
++static void io_sq_thread_finish(struct io_ring_ctx *ctx)
++{
++	struct io_sq_data *sqd = ctx->sq_data;
++
++	if (sqd) {
++		io_sq_thread_park(sqd);
++		list_del_init(&ctx->sqd_list);
++		io_sqd_update_thread_idle(sqd);
++		io_sq_thread_unpark(sqd);
++
++		io_put_sq_data(sqd);
++		ctx->sq_data = NULL;
++	}
++}
++
++static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
++{
++	struct io_ring_ctx *ctx_attach;
++	struct io_sq_data *sqd;
++	struct fd f;
++
++	f = fdget(p->wq_fd);
++	if (!f.file)
++		return ERR_PTR(-ENXIO);
++	if (f.file->f_op != &io_uring_fops) {
++		fdput(f);
++		return ERR_PTR(-EINVAL);
++	}
++
++	ctx_attach = f.file->private_data;
++	sqd = ctx_attach->sq_data;
++	if (!sqd) {
++		fdput(f);
++		return ERR_PTR(-EINVAL);
++	}
++	if (sqd->task_tgid != current->tgid) {
++		fdput(f);
++		return ERR_PTR(-EPERM);
++	}
++
++	refcount_inc(&sqd->refs);
++	fdput(f);
++	return sqd;
++}
++
++static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
++					 bool *attached)
++{
++	struct io_sq_data *sqd;
++
++	*attached = false;
++	if (p->flags & IORING_SETUP_ATTACH_WQ) {
++		sqd = io_attach_sq_data(p);
++		if (!IS_ERR(sqd)) {
++			*attached = true;
++			return sqd;
++		}
++		/* fall through for EPERM case, setup new sqd/task */
++		if (PTR_ERR(sqd) != -EPERM)
++			return sqd;
++	}
++
++	sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
++	if (!sqd)
++		return ERR_PTR(-ENOMEM);
++
++	atomic_set(&sqd->park_pending, 0);
++	refcount_set(&sqd->refs, 1);
++	INIT_LIST_HEAD(&sqd->ctx_list);
++	mutex_init(&sqd->lock);
++	init_waitqueue_head(&sqd->wait);
++	init_completion(&sqd->exited);
++	return sqd;
++}
++
++#if defined(CONFIG_UNIX)
++/*
++ * Ensure the UNIX gc is aware of our file set, so we are certain that
++ * the io_uring can be safely unregistered on process exit, even if we have
++ * loops in the file referencing.
++ */
++static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
++{
++	struct sock *sk = ctx->ring_sock->sk;
++	struct scm_fp_list *fpl;
++	struct sk_buff *skb;
++	int i, nr_files;
++
++	fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
++	if (!fpl)
++		return -ENOMEM;
++
++	skb = alloc_skb(0, GFP_KERNEL);
++	if (!skb) {
++		kfree(fpl);
++		return -ENOMEM;
++	}
++
++	skb->sk = sk;
++	skb->scm_io_uring = 1;
++
++	nr_files = 0;
++	fpl->user = get_uid(current_user());
++	for (i = 0; i < nr; i++) {
++		struct file *file = io_file_from_index(ctx, i + offset);
++
++		if (!file)
++			continue;
++		fpl->fp[nr_files] = get_file(file);
++		unix_inflight(fpl->user, fpl->fp[nr_files]);
++		nr_files++;
++	}
++
++	if (nr_files) {
++		fpl->max = SCM_MAX_FD;
++		fpl->count = nr_files;
++		UNIXCB(skb).fp = fpl;
++		skb->destructor = unix_destruct_scm;
++		refcount_add(skb->truesize, &sk->sk_wmem_alloc);
++		skb_queue_head(&sk->sk_receive_queue, skb);
++
++		for (i = 0; i < nr; i++) {
++			struct file *file = io_file_from_index(ctx, i + offset);
++
++			if (file)
++				fput(file);
++		}
++	} else {
++		kfree_skb(skb);
++		free_uid(fpl->user);
++		kfree(fpl);
++	}
++
++	return 0;
++}
++
++/*
++ * If UNIX sockets are enabled, fd passing can cause a reference cycle which
++ * causes regular reference counting to break down. We rely on the UNIX
++ * garbage collection to take care of this problem for us.
++ */
++static int io_sqe_files_scm(struct io_ring_ctx *ctx)
++{
++	unsigned left, total;
++	int ret = 0;
++
++	total = 0;
++	left = ctx->nr_user_files;
++	while (left) {
++		unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
++
++		ret = __io_sqe_files_scm(ctx, this_files, total);
++		if (ret)
++			break;
++		left -= this_files;
++		total += this_files;
++	}
++
++	if (!ret)
++		return 0;
++
++	while (total < ctx->nr_user_files) {
++		struct file *file = io_file_from_index(ctx, total);
++
++		if (file)
++			fput(file);
++		total++;
++	}
++
++	return ret;
++}
++#else
++static int io_sqe_files_scm(struct io_ring_ctx *ctx)
++{
++	return 0;
++}
++#endif
++
++static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
++{
++	struct file *file = prsrc->file;
++#if defined(CONFIG_UNIX)
++	struct sock *sock = ctx->ring_sock->sk;
++	struct sk_buff_head list, *head = &sock->sk_receive_queue;
++	struct sk_buff *skb;
++	int i;
++
++	__skb_queue_head_init(&list);
++
++	/*
++	 * Find the skb that holds this file in its SCM_RIGHTS. When found,
++	 * remove this entry and rearrange the file array.
++	 */
++	skb = skb_dequeue(head);
++	while (skb) {
++		struct scm_fp_list *fp;
++
++		fp = UNIXCB(skb).fp;
++		for (i = 0; i < fp->count; i++) {
++			int left;
++
++			if (fp->fp[i] != file)
++				continue;
++
++			unix_notinflight(fp->user, fp->fp[i]);
++			left = fp->count - 1 - i;
++			if (left) {
++				memmove(&fp->fp[i], &fp->fp[i + 1],
++						left * sizeof(struct file *));
++			}
++			fp->count--;
++			if (!fp->count) {
++				kfree_skb(skb);
++				skb = NULL;
++			} else {
++				__skb_queue_tail(&list, skb);
++			}
++			fput(file);
++			file = NULL;
++			break;
++		}
++
++		if (!file)
++			break;
++
++		__skb_queue_tail(&list, skb);
++
++		skb = skb_dequeue(head);
++	}
++
++	if (skb_peek(&list)) {
++		spin_lock_irq(&head->lock);
++		while ((skb = __skb_dequeue(&list)) != NULL)
++			__skb_queue_tail(head, skb);
++		spin_unlock_irq(&head->lock);
++	}
++#else
++	fput(file);
++#endif
++}
++
++static void __io_rsrc_put_work(struct io_rsrc_node *ref_node)
++{
++	struct io_rsrc_data *rsrc_data = ref_node->rsrc_data;
++	struct io_ring_ctx *ctx = rsrc_data->ctx;
++	struct io_rsrc_put *prsrc, *tmp;
++
++	list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
++		list_del(&prsrc->list);
++
++		if (prsrc->tag) {
++			bool lock_ring = ctx->flags & IORING_SETUP_IOPOLL;
++
++			io_ring_submit_lock(ctx, lock_ring);
++			spin_lock(&ctx->completion_lock);
++			io_fill_cqe_aux(ctx, prsrc->tag, 0, 0);
++			io_commit_cqring(ctx);
++			spin_unlock(&ctx->completion_lock);
++			io_cqring_ev_posted(ctx);
++			io_ring_submit_unlock(ctx, lock_ring);
++		}
++
++		rsrc_data->do_put(ctx, prsrc);
++		kfree(prsrc);
++	}
++
++	io_rsrc_node_destroy(ref_node);
++	if (atomic_dec_and_test(&rsrc_data->refs))
++		complete(&rsrc_data->done);
++}
++
++static void io_rsrc_put_work(struct work_struct *work)
++{
++	struct io_ring_ctx *ctx;
++	struct llist_node *node;
++
++	ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
++	node = llist_del_all(&ctx->rsrc_put_llist);
++
++	while (node) {
++		struct io_rsrc_node *ref_node;
++		struct llist_node *next = node->next;
++
++		ref_node = llist_entry(node, struct io_rsrc_node, llist);
++		__io_rsrc_put_work(ref_node);
++		node = next;
++	}
++}
++
++static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
++				 unsigned nr_args, u64 __user *tags)
++{
++	__s32 __user *fds = (__s32 __user *) arg;
++	struct file *file;
++	int fd, ret;
++	unsigned i;
++
++	if (ctx->file_data)
++		return -EBUSY;
++	if (!nr_args)
++		return -EINVAL;
++	if (nr_args > IORING_MAX_FIXED_FILES)
++		return -EMFILE;
++	if (nr_args > rlimit(RLIMIT_NOFILE))
++		return -EMFILE;
++	ret = io_rsrc_node_switch_start(ctx);
++	if (ret)
++		return ret;
++	ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args,
++				 &ctx->file_data);
++	if (ret)
++		return ret;
++
++	ret = -ENOMEM;
++	if (!io_alloc_file_tables(&ctx->file_table, nr_args))
++		goto out_free;
++
++	for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
++		if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
++			ret = -EFAULT;
++			goto out_fput;
++		}
++		/* allow sparse sets */
++		if (fd == -1) {
++			ret = -EINVAL;
++			if (unlikely(*io_get_tag_slot(ctx->file_data, i)))
++				goto out_fput;
++			continue;
++		}
++
++		file = fget(fd);
++		ret = -EBADF;
++		if (unlikely(!file))
++			goto out_fput;
++
++		/*
++		 * Don't allow io_uring instances to be registered. If UNIX
++		 * isn't enabled, then this causes a reference cycle and this
++		 * instance can never get freed. If UNIX is enabled we'll
++		 * handle it just fine, but there's still no point in allowing
++		 * a ring fd as it doesn't support regular read/write anyway.
++		 */
++		if (file->f_op == &io_uring_fops) {
++			fput(file);
++			goto out_fput;
++		}
++		io_fixed_file_set(io_fixed_file_slot(&ctx->file_table, i), file);
++	}
++
++	ret = io_sqe_files_scm(ctx);
++	if (ret) {
++		__io_sqe_files_unregister(ctx);
++		return ret;
++	}
++
++	io_rsrc_node_switch(ctx, NULL);
++	return ret;
++out_fput:
++	for (i = 0; i < ctx->nr_user_files; i++) {
++		file = io_file_from_index(ctx, i);
++		if (file)
++			fput(file);
++	}
++	io_free_file_tables(&ctx->file_table);
++	ctx->nr_user_files = 0;
++out_free:
++	io_rsrc_data_free(ctx->file_data);
++	ctx->file_data = NULL;
++	return ret;
++}
++
++static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
++				int index)
++{
++#if defined(CONFIG_UNIX)
++	struct sock *sock = ctx->ring_sock->sk;
++	struct sk_buff_head *head = &sock->sk_receive_queue;
++	struct sk_buff *skb;
++
++	/*
++	 * See if we can merge this file into an existing skb SCM_RIGHTS
++	 * file set. If there's no room, fall back to allocating a new skb
++	 * and filling it in.
++	 */
++	spin_lock_irq(&head->lock);
++	skb = skb_peek(head);
++	if (skb) {
++		struct scm_fp_list *fpl = UNIXCB(skb).fp;
++
++		if (fpl->count < SCM_MAX_FD) {
++			__skb_unlink(skb, head);
++			spin_unlock_irq(&head->lock);
++			fpl->fp[fpl->count] = get_file(file);
++			unix_inflight(fpl->user, fpl->fp[fpl->count]);
++			fpl->count++;
++			spin_lock_irq(&head->lock);
++			__skb_queue_head(head, skb);
++		} else {
++			skb = NULL;
++		}
++	}
++	spin_unlock_irq(&head->lock);
++
++	if (skb) {
++		fput(file);
++		return 0;
++	}
++
++	return __io_sqe_files_scm(ctx, 1, index);
++#else
++	return 0;
++#endif
++}
++
++static int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
++				 struct io_rsrc_node *node, void *rsrc)
++{
++	u64 *tag_slot = io_get_tag_slot(data, idx);
++	struct io_rsrc_put *prsrc;
++
++	prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
++	if (!prsrc)
++		return -ENOMEM;
++
++	prsrc->tag = *tag_slot;
++	*tag_slot = 0;
++	prsrc->rsrc = rsrc;
++	list_add(&prsrc->list, &node->rsrc_list);
++	return 0;
++}
++
++static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
++				 unsigned int issue_flags, u32 slot_index)
++{
++	struct io_ring_ctx *ctx = req->ctx;
++	bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
++	bool needs_switch = false;
++	struct io_fixed_file *file_slot;
++	int ret = -EBADF;
++
++	io_ring_submit_lock(ctx, !force_nonblock);
++	if (file->f_op == &io_uring_fops)
++		goto err;
++	ret = -ENXIO;
++	if (!ctx->file_data)
++		goto err;
++	ret = -EINVAL;
++	if (slot_index >= ctx->nr_user_files)
++		goto err;
++
++	slot_index = array_index_nospec(slot_index, ctx->nr_user_files);
++	file_slot = io_fixed_file_slot(&ctx->file_table, slot_index);
++
++	if (file_slot->file_ptr) {
++		struct file *old_file;
++
++		ret = io_rsrc_node_switch_start(ctx);
++		if (ret)
++			goto err;
++
++		old_file = (struct file *)(file_slot->file_ptr & FFS_MASK);
++		ret = io_queue_rsrc_removal(ctx->file_data, slot_index,
++					    ctx->rsrc_node, old_file);
++		if (ret)
++			goto err;
++		file_slot->file_ptr = 0;
++		needs_switch = true;
++	}
++
++	*io_get_tag_slot(ctx->file_data, slot_index) = 0;
++	io_fixed_file_set(file_slot, file);
++	ret = io_sqe_file_register(ctx, file, slot_index);
++	if (ret) {
++		file_slot->file_ptr = 0;
++		goto err;
++	}
++
++	ret = 0;
++err:
++	if (needs_switch)
++		io_rsrc_node_switch(ctx, ctx->file_data);
++	io_ring_submit_unlock(ctx, !force_nonblock);
++	if (ret)
++		fput(file);
++	return ret;
++}
++
++static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags)
++{
++	unsigned int offset = req->close.file_slot - 1;
++	struct io_ring_ctx *ctx = req->ctx;
++	struct io_fixed_file *file_slot;
++	struct file *file;
++	int ret;
++
++	io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
++	ret = -ENXIO;
++	if (unlikely(!ctx->file_data))
++		goto out;
++	ret = -EINVAL;
++	if (offset >= ctx->nr_user_files)
++		goto out;
++	ret = io_rsrc_node_switch_start(ctx);
++	if (ret)
++		goto out;
++
++	offset = array_index_nospec(offset, ctx->nr_user_files);
++	file_slot = io_fixed_file_slot(&ctx->file_table, offset);
++	ret = -EBADF;
++	if (!file_slot->file_ptr)
++		goto out;
++
++	file = (struct file *)(file_slot->file_ptr & FFS_MASK);
++	ret = io_queue_rsrc_removal(ctx->file_data, offset, ctx->rsrc_node, file);
++	if (ret)
++		goto out;
++
++	file_slot->file_ptr = 0;
++	io_rsrc_node_switch(ctx, ctx->file_data);
++	ret = 0;
++out:
++	io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
++	return ret;
++}
++
++static int __io_sqe_files_update(struct io_ring_ctx *ctx,
++				 struct io_uring_rsrc_update2 *up,
++				 unsigned nr_args)
++{
++	u64 __user *tags = u64_to_user_ptr(up->tags);
++	__s32 __user *fds = u64_to_user_ptr(up->data);
++	struct io_rsrc_data *data = ctx->file_data;
++	struct io_fixed_file *file_slot;
++	struct file *file;
++	int fd, i, err = 0;
++	unsigned int done;
++	bool needs_switch = false;
++
++	if (!ctx->file_data)
++		return -ENXIO;
++	if (up->offset + nr_args > ctx->nr_user_files)
++		return -EINVAL;
++
++	for (done = 0; done < nr_args; done++) {
++		u64 tag = 0;
++
++		if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) ||
++		    copy_from_user(&fd, &fds[done], sizeof(fd))) {
++			err = -EFAULT;
++			break;
++		}
++		if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) {
++			err = -EINVAL;
++			break;
++		}
++		if (fd == IORING_REGISTER_FILES_SKIP)
++			continue;
++
++		i = array_index_nospec(up->offset + done, ctx->nr_user_files);
++		file_slot = io_fixed_file_slot(&ctx->file_table, i);
++
++		if (file_slot->file_ptr) {
++			file = (struct file *)(file_slot->file_ptr & FFS_MASK);
++			err = io_queue_rsrc_removal(data, i, ctx->rsrc_node, file);
++			if (err)
++				break;
++			file_slot->file_ptr = 0;
++			needs_switch = true;
++		}
++		if (fd != -1) {
++			file = fget(fd);
++			if (!file) {
++				err = -EBADF;
++				break;
++			}
++			/*
++			 * Don't allow io_uring instances to be registered. If
++			 * UNIX isn't enabled, then this causes a reference
++			 * cycle and this instance can never get freed. If UNIX
++			 * is enabled we'll handle it just fine, but there's
++			 * still no point in allowing a ring fd as it doesn't
++			 * support regular read/write anyway.
++			 */
++			if (file->f_op == &io_uring_fops) {
++				fput(file);
++				err = -EBADF;
++				break;
++			}
++			*io_get_tag_slot(data, i) = tag;
++			io_fixed_file_set(file_slot, file);
++			err = io_sqe_file_register(ctx, file, i);
++			if (err) {
++				file_slot->file_ptr = 0;
++				fput(file);
++				break;
++			}
++		}
++	}
++
++	if (needs_switch)
++		io_rsrc_node_switch(ctx, data);
++	return done ? done : err;
++}
++
++static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
++					struct task_struct *task)
++{
++	struct io_wq_hash *hash;
++	struct io_wq_data data;
++	unsigned int concurrency;
++
++	mutex_lock(&ctx->uring_lock);
++	hash = ctx->hash_map;
++	if (!hash) {
++		hash = kzalloc(sizeof(*hash), GFP_KERNEL);
++		if (!hash) {
++			mutex_unlock(&ctx->uring_lock);
++			return ERR_PTR(-ENOMEM);
++		}
++		refcount_set(&hash->refs, 1);
++		init_waitqueue_head(&hash->wait);
++		ctx->hash_map = hash;
++	}
++	mutex_unlock(&ctx->uring_lock);
++
++	data.hash = hash;
++	data.task = task;
++	data.free_work = io_wq_free_work;
++	data.do_work = io_wq_submit_work;
++
++	/* Do QD, or 4 * CPUS, whatever is smallest */
++	concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
++
++	return io_wq_create(concurrency, &data);
++}
++
++static int io_uring_alloc_task_context(struct task_struct *task,
++				       struct io_ring_ctx *ctx)
++{
++	struct io_uring_task *tctx;
++	int ret;
++
++	tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
++	if (unlikely(!tctx))
++		return -ENOMEM;
++
++	ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
++	if (unlikely(ret)) {
++		kfree(tctx);
++		return ret;
++	}
++
++	tctx->io_wq = io_init_wq_offload(ctx, task);
++	if (IS_ERR(tctx->io_wq)) {
++		ret = PTR_ERR(tctx->io_wq);
++		percpu_counter_destroy(&tctx->inflight);
++		kfree(tctx);
++		return ret;
++	}
++
++	xa_init(&tctx->xa);
++	init_waitqueue_head(&tctx->wait);
++	atomic_set(&tctx->in_idle, 0);
++	atomic_set(&tctx->inflight_tracked, 0);
++	task->io_uring = tctx;
++	spin_lock_init(&tctx->task_lock);
++	INIT_WQ_LIST(&tctx->task_list);
++	init_task_work(&tctx->task_work, tctx_task_work);
++	return 0;
++}
++
++void __io_uring_free(struct task_struct *tsk)
++{
++	struct io_uring_task *tctx = tsk->io_uring;
++
++	WARN_ON_ONCE(!xa_empty(&tctx->xa));
++	WARN_ON_ONCE(tctx->io_wq);
++	WARN_ON_ONCE(tctx->cached_refs);
++
++	percpu_counter_destroy(&tctx->inflight);
++	kfree(tctx);
++	tsk->io_uring = NULL;
++}
++
++static int io_sq_offload_create(struct io_ring_ctx *ctx,
++				struct io_uring_params *p)
++{
++	int ret;
++
++	/* Retain compatibility with failing for an invalid attach attempt */
++	if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
++				IORING_SETUP_ATTACH_WQ) {
++		struct fd f;
++
++		f = fdget(p->wq_fd);
++		if (!f.file)
++			return -ENXIO;
++		if (f.file->f_op != &io_uring_fops) {
++			fdput(f);
++			return -EINVAL;
++		}
++		fdput(f);
++	}
++	if (ctx->flags & IORING_SETUP_SQPOLL) {
++		struct task_struct *tsk;
++		struct io_sq_data *sqd;
++		bool attached;
++
++		sqd = io_get_sq_data(p, &attached);
++		if (IS_ERR(sqd)) {
++			ret = PTR_ERR(sqd);
++			goto err;
++		}
++
++		ctx->sq_creds = get_current_cred();
++		ctx->sq_data = sqd;
++		ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
++		if (!ctx->sq_thread_idle)
++			ctx->sq_thread_idle = HZ;
++
++		io_sq_thread_park(sqd);
++		list_add(&ctx->sqd_list, &sqd->ctx_list);
++		io_sqd_update_thread_idle(sqd);
++		/* don't attach to a dying SQPOLL thread, would be racy */
++		ret = (attached && !sqd->thread) ? -ENXIO : 0;
++		io_sq_thread_unpark(sqd);
++
++		if (ret < 0)
++			goto err;
++		if (attached)
++			return 0;
++
++		if (p->flags & IORING_SETUP_SQ_AFF) {
++			int cpu = p->sq_thread_cpu;
++
++			ret = -EINVAL;
++			if (cpu >= nr_cpu_ids || !cpu_online(cpu))
++				goto err_sqpoll;
++			sqd->sq_cpu = cpu;
++		} else {
++			sqd->sq_cpu = -1;
++		}
++
++		sqd->task_pid = current->pid;
++		sqd->task_tgid = current->tgid;
++		tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
++		if (IS_ERR(tsk)) {
++			ret = PTR_ERR(tsk);
++			goto err_sqpoll;
++		}
++
++		sqd->thread = tsk;
++		ret = io_uring_alloc_task_context(tsk, ctx);
++		wake_up_new_task(tsk);
++		if (ret)
++			goto err;
++	} else if (p->flags & IORING_SETUP_SQ_AFF) {
++		/* Can't have SQ_AFF without SQPOLL */
++		ret = -EINVAL;
++		goto err;
++	}
++
++	return 0;
++err_sqpoll:
++	complete(&ctx->sq_data->exited);
++err:
++	io_sq_thread_finish(ctx);
++	return ret;
++}
++
++static inline void __io_unaccount_mem(struct user_struct *user,
++				      unsigned long nr_pages)
++{
++	atomic_long_sub(nr_pages, &user->locked_vm);
++}
++
++static inline int __io_account_mem(struct user_struct *user,
++				   unsigned long nr_pages)
++{
++	unsigned long page_limit, cur_pages, new_pages;
++
++	/* Don't allow more pages than we can safely lock */
++	page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
++
++	do {
++		cur_pages = atomic_long_read(&user->locked_vm);
++		new_pages = cur_pages + nr_pages;
++		if (new_pages > page_limit)
++			return -ENOMEM;
++	} while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
++					new_pages) != cur_pages);
++
++	return 0;
++}
++
++static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
++{
++	if (ctx->user)
++		__io_unaccount_mem(ctx->user, nr_pages);
++
++	if (ctx->mm_account)
++		atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
++}
++
++static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
++{
++	int ret;
++
++	if (ctx->user) {
++		ret = __io_account_mem(ctx->user, nr_pages);
++		if (ret)
++			return ret;
++	}
++
++	if (ctx->mm_account)
++		atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
++
++	return 0;
++}
++
++static void io_mem_free(void *ptr)
++{
++	struct page *page;
++
++	if (!ptr)
++		return;
++
++	page = virt_to_head_page(ptr);
++	if (put_page_testzero(page))
++		free_compound_page(page);
++}
++
++static void *io_mem_alloc(size_t size)
++{
++	gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP;
++
++	return (void *) __get_free_pages(gfp, get_order(size));
++}
++
++static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
++				size_t *sq_offset)
++{
++	struct io_rings *rings;
++	size_t off, sq_array_size;
++
++	off = struct_size(rings, cqes, cq_entries);
++	if (off == SIZE_MAX)
++		return SIZE_MAX;
++
++#ifdef CONFIG_SMP
++	off = ALIGN(off, SMP_CACHE_BYTES);
++	if (off == 0)
++		return SIZE_MAX;
++#endif
++
++	if (sq_offset)
++		*sq_offset = off;
++
++	sq_array_size = array_size(sizeof(u32), sq_entries);
++	if (sq_array_size == SIZE_MAX)
++		return SIZE_MAX;
++
++	if (check_add_overflow(off, sq_array_size, &off))
++		return SIZE_MAX;
++
++	return off;
++}
++
++static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot)
++{
++	struct io_mapped_ubuf *imu = *slot;
++	unsigned int i;
++
++	if (imu != ctx->dummy_ubuf) {
++		for (i = 0; i < imu->nr_bvecs; i++)
++			unpin_user_page(imu->bvec[i].bv_page);
++		if (imu->acct_pages)
++			io_unaccount_mem(ctx, imu->acct_pages);
++		kvfree(imu);
++	}
++	*slot = NULL;
++}
++
++static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
++{
++	io_buffer_unmap(ctx, &prsrc->buf);
++	prsrc->buf = NULL;
++}
++
++static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
++{
++	unsigned int i;
++
++	for (i = 0; i < ctx->nr_user_bufs; i++)
++		io_buffer_unmap(ctx, &ctx->user_bufs[i]);
++	kfree(ctx->user_bufs);
++	io_rsrc_data_free(ctx->buf_data);
++	ctx->user_bufs = NULL;
++	ctx->buf_data = NULL;
++	ctx->nr_user_bufs = 0;
++}
++
++static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
++{
++	unsigned nr = ctx->nr_user_bufs;
++	int ret;
++
++	if (!ctx->buf_data)
++		return -ENXIO;
++
++	/*
++	 * Quiesce may unlock ->uring_lock, and while it's not held
++	 * prevent new requests using the table.
++	 */
++	ctx->nr_user_bufs = 0;
++	ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx);
++	ctx->nr_user_bufs = nr;
++	if (!ret)
++		__io_sqe_buffers_unregister(ctx);
++	return ret;
++}
++
++static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
++		       void __user *arg, unsigned index)
++{
++	struct iovec __user *src;
++
++#ifdef CONFIG_COMPAT
++	if (ctx->compat) {
++		struct compat_iovec __user *ciovs;
++		struct compat_iovec ciov;
++
++		ciovs = (struct compat_iovec __user *) arg;
++		if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
++			return -EFAULT;
++
++		dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
++		dst->iov_len = ciov.iov_len;
++		return 0;
++	}
++#endif
++	src = (struct iovec __user *) arg;
++	if (copy_from_user(dst, &src[index], sizeof(*dst)))
++		return -EFAULT;
++	return 0;
++}
++
++/*
++ * Not super efficient, but this is just a registration time. And we do cache
++ * the last compound head, so generally we'll only do a full search if we don't
++ * match that one.
++ *
++ * We check if the given compound head page has already been accounted, to
++ * avoid double accounting it. This allows us to account the full size of the
++ * page, not just the constituent pages of a huge page.
++ */
++static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
++				  int nr_pages, struct page *hpage)
++{
++	int i, j;
++
++	/* check current page array */
++	for (i = 0; i < nr_pages; i++) {
++		if (!PageCompound(pages[i]))
++			continue;
++		if (compound_head(pages[i]) == hpage)
++			return true;
++	}
++
++	/* check previously registered pages */
++	for (i = 0; i < ctx->nr_user_bufs; i++) {
++		struct io_mapped_ubuf *imu = ctx->user_bufs[i];
++
++		for (j = 0; j < imu->nr_bvecs; j++) {
++			if (!PageCompound(imu->bvec[j].bv_page))
++				continue;
++			if (compound_head(imu->bvec[j].bv_page) == hpage)
++				return true;
++		}
++	}
++
++	return false;
++}
++
++static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
++				 int nr_pages, struct io_mapped_ubuf *imu,
++				 struct page **last_hpage)
++{
++	int i, ret;
++
++	imu->acct_pages = 0;
++	for (i = 0; i < nr_pages; i++) {
++		if (!PageCompound(pages[i])) {
++			imu->acct_pages++;
++		} else {
++			struct page *hpage;
++
++			hpage = compound_head(pages[i]);
++			if (hpage == *last_hpage)
++				continue;
++			*last_hpage = hpage;
++			if (headpage_already_acct(ctx, pages, i, hpage))
++				continue;
++			imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
++		}
++	}
++
++	if (!imu->acct_pages)
++		return 0;
++
++	ret = io_account_mem(ctx, imu->acct_pages);
++	if (ret)
++		imu->acct_pages = 0;
++	return ret;
++}
++
++static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
++				  struct io_mapped_ubuf **pimu,
++				  struct page **last_hpage)
++{
++	struct io_mapped_ubuf *imu = NULL;
++	struct vm_area_struct **vmas = NULL;
++	struct page **pages = NULL;
++	unsigned long off, start, end, ubuf;
++	size_t size;
++	int ret, pret, nr_pages, i;
++
++	if (!iov->iov_base) {
++		*pimu = ctx->dummy_ubuf;
++		return 0;
++	}
++
++	ubuf = (unsigned long) iov->iov_base;
++	end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
++	start = ubuf >> PAGE_SHIFT;
++	nr_pages = end - start;
++
++	*pimu = NULL;
++	ret = -ENOMEM;
++
++	pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
++	if (!pages)
++		goto done;
++
++	vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
++			      GFP_KERNEL);
++	if (!vmas)
++		goto done;
++
++	imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL);
++	if (!imu)
++		goto done;
++
++	ret = 0;
++	mmap_read_lock(current->mm);
++	pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
++			      pages, vmas);
++	if (pret == nr_pages) {
++		/* don't support file backed memory */
++		for (i = 0; i < nr_pages; i++) {
++			struct vm_area_struct *vma = vmas[i];
++
++			if (vma_is_shmem(vma))
++				continue;
++			if (vma->vm_file &&
++			    !is_file_hugepages(vma->vm_file)) {
++				ret = -EOPNOTSUPP;
++				break;
++			}
++		}
++	} else {
++		ret = pret < 0 ? pret : -EFAULT;
++	}
++	mmap_read_unlock(current->mm);
++	if (ret) {
++		/*
++		 * if we did partial map, or found file backed vmas,
++		 * release any pages we did get
++		 */
++		if (pret > 0)
++			unpin_user_pages(pages, pret);
++		goto done;
++	}
++
++	ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage);
++	if (ret) {
++		unpin_user_pages(pages, pret);
++		goto done;
++	}
++
++	off = ubuf & ~PAGE_MASK;
++	size = iov->iov_len;
++	for (i = 0; i < nr_pages; i++) {
++		size_t vec_len;
++
++		vec_len = min_t(size_t, size, PAGE_SIZE - off);
++		imu->bvec[i].bv_page = pages[i];
++		imu->bvec[i].bv_len = vec_len;
++		imu->bvec[i].bv_offset = off;
++		off = 0;
++		size -= vec_len;
++	}
++	/* store original address for later verification */
++	imu->ubuf = ubuf;
++	imu->ubuf_end = ubuf + iov->iov_len;
++	imu->nr_bvecs = nr_pages;
++	*pimu = imu;
++	ret = 0;
++done:
++	if (ret)
++		kvfree(imu);
++	kvfree(pages);
++	kvfree(vmas);
++	return ret;
++}
++
++static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
++{
++	ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL);
++	return ctx->user_bufs ? 0 : -ENOMEM;
++}
++
++static int io_buffer_validate(struct iovec *iov)
++{
++	unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1);
++
++	/*
++	 * Don't impose further limits on the size and buffer
++	 * constraints here, we'll -EINVAL later when IO is
++	 * submitted if they are wrong.
++	 */
++	if (!iov->iov_base)
++		return iov->iov_len ? -EFAULT : 0;
++	if (!iov->iov_len)
++		return -EFAULT;
++
++	/* arbitrary limit, but we need something */
++	if (iov->iov_len > SZ_1G)
++		return -EFAULT;
++
++	if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp))
++		return -EOVERFLOW;
++
++	return 0;
++}
++
++static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
++				   unsigned int nr_args, u64 __user *tags)
++{
++	struct page *last_hpage = NULL;
++	struct io_rsrc_data *data;
++	int i, ret;
++	struct iovec iov;
++
++	if (ctx->user_bufs)
++		return -EBUSY;
++	if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS)
++		return -EINVAL;
++	ret = io_rsrc_node_switch_start(ctx);
++	if (ret)
++		return ret;
++	ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data);
++	if (ret)
++		return ret;
++	ret = io_buffers_map_alloc(ctx, nr_args);
++	if (ret) {
++		io_rsrc_data_free(data);
++		return ret;
++	}
++
++	for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) {
++		ret = io_copy_iov(ctx, &iov, arg, i);
++		if (ret)
++			break;
++		ret = io_buffer_validate(&iov);
++		if (ret)
++			break;
++		if (!iov.iov_base && *io_get_tag_slot(data, i)) {
++			ret = -EINVAL;
++			break;
++		}
++
++		ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i],
++					     &last_hpage);
++		if (ret)
++			break;
++	}
++
++	WARN_ON_ONCE(ctx->buf_data);
++
++	ctx->buf_data = data;
++	if (ret)
++		__io_sqe_buffers_unregister(ctx);
++	else
++		io_rsrc_node_switch(ctx, NULL);
++	return ret;
++}
++
++static int __io_sqe_buffers_update(struct io_ring_ctx *ctx,
++				   struct io_uring_rsrc_update2 *up,
++				   unsigned int nr_args)
++{
++	u64 __user *tags = u64_to_user_ptr(up->tags);
++	struct iovec iov, __user *iovs = u64_to_user_ptr(up->data);
++	struct page *last_hpage = NULL;
++	bool needs_switch = false;
++	__u32 done;
++	int i, err;
++
++	if (!ctx->buf_data)
++		return -ENXIO;
++	if (up->offset + nr_args > ctx->nr_user_bufs)
++		return -EINVAL;
++
++	for (done = 0; done < nr_args; done++) {
++		struct io_mapped_ubuf *imu;
++		int offset = up->offset + done;
++		u64 tag = 0;
++
++		err = io_copy_iov(ctx, &iov, iovs, done);
++		if (err)
++			break;
++		if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) {
++			err = -EFAULT;
++			break;
++		}
++		err = io_buffer_validate(&iov);
++		if (err)
++			break;
++		if (!iov.iov_base && tag) {
++			err = -EINVAL;
++			break;
++		}
++		err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage);
++		if (err)
++			break;
++
++		i = array_index_nospec(offset, ctx->nr_user_bufs);
++		if (ctx->user_bufs[i] != ctx->dummy_ubuf) {
++			err = io_queue_rsrc_removal(ctx->buf_data, i,
++						    ctx->rsrc_node, ctx->user_bufs[i]);
++			if (unlikely(err)) {
++				io_buffer_unmap(ctx, &imu);
++				break;
++			}
++			ctx->user_bufs[i] = NULL;
++			needs_switch = true;
++		}
++
++		ctx->user_bufs[i] = imu;
++		*io_get_tag_slot(ctx->buf_data, offset) = tag;
++	}
++
++	if (needs_switch)
++		io_rsrc_node_switch(ctx, ctx->buf_data);
++	return done ? done : err;
++}
++
++static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
++{
++	__s32 __user *fds = arg;
++	int fd;
++
++	if (ctx->cq_ev_fd)
++		return -EBUSY;
++
++	if (copy_from_user(&fd, fds, sizeof(*fds)))
++		return -EFAULT;
++
++	ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
++	if (IS_ERR(ctx->cq_ev_fd)) {
++		int ret = PTR_ERR(ctx->cq_ev_fd);
++
++		ctx->cq_ev_fd = NULL;
++		return ret;
++	}
++
++	return 0;
++}
++
++static int io_eventfd_unregister(struct io_ring_ctx *ctx)
++{
++	if (ctx->cq_ev_fd) {
++		eventfd_ctx_put(ctx->cq_ev_fd);
++		ctx->cq_ev_fd = NULL;
++		return 0;
++	}
++
++	return -ENXIO;
++}
++
++static void io_destroy_buffers(struct io_ring_ctx *ctx)
++{
++	struct io_buffer *buf;
++	unsigned long index;
++
++	xa_for_each(&ctx->io_buffers, index, buf)
++		__io_remove_buffers(ctx, buf, index, -1U);
++}
++
++static void io_req_cache_free(struct list_head *list)
++{
++	struct io_kiocb *req, *nxt;
++
++	list_for_each_entry_safe(req, nxt, list, inflight_entry) {
++		list_del(&req->inflight_entry);
++		kmem_cache_free(req_cachep, req);
++	}
++}
++
++static void io_req_caches_free(struct io_ring_ctx *ctx)
++{
++	struct io_submit_state *state = &ctx->submit_state;
++
++	mutex_lock(&ctx->uring_lock);
++
++	if (state->free_reqs) {
++		kmem_cache_free_bulk(req_cachep, state->free_reqs, state->reqs);
++		state->free_reqs = 0;
++	}
++
++	io_flush_cached_locked_reqs(ctx, state);
++	io_req_cache_free(&state->free_list);
++	mutex_unlock(&ctx->uring_lock);
++}
++
++static void io_wait_rsrc_data(struct io_rsrc_data *data)
++{
++	if (data && !atomic_dec_and_test(&data->refs))
++		wait_for_completion(&data->done);
++}
++
++static void io_ring_ctx_free(struct io_ring_ctx *ctx)
++{
++	io_sq_thread_finish(ctx);
++
++	/* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */
++	io_wait_rsrc_data(ctx->buf_data);
++	io_wait_rsrc_data(ctx->file_data);
++
++	mutex_lock(&ctx->uring_lock);
++	if (ctx->buf_data)
++		__io_sqe_buffers_unregister(ctx);
++	if (ctx->file_data)
++		__io_sqe_files_unregister(ctx);
++	if (ctx->rings)
++		__io_cqring_overflow_flush(ctx, true);
++	mutex_unlock(&ctx->uring_lock);
++	io_eventfd_unregister(ctx);
++	io_destroy_buffers(ctx);
++	if (ctx->sq_creds)
++		put_cred(ctx->sq_creds);
++
++	/* there are no registered resources left, nobody uses it */
++	if (ctx->rsrc_node)
++		io_rsrc_node_destroy(ctx->rsrc_node);
++	if (ctx->rsrc_backup_node)
++		io_rsrc_node_destroy(ctx->rsrc_backup_node);
++	flush_delayed_work(&ctx->rsrc_put_work);
++
++	WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list));
++	WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist));
++
++#if defined(CONFIG_UNIX)
++	if (ctx->ring_sock) {
++		ctx->ring_sock->file = NULL; /* so that iput() is called */
++		sock_release(ctx->ring_sock);
++	}
++#endif
++	WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list));
++
++	if (ctx->mm_account) {
++		mmdrop(ctx->mm_account);
++		ctx->mm_account = NULL;
++	}
++
++	io_mem_free(ctx->rings);
++	io_mem_free(ctx->sq_sqes);
++
++	percpu_ref_exit(&ctx->refs);
++	free_uid(ctx->user);
++	io_req_caches_free(ctx);
++	if (ctx->hash_map)
++		io_wq_put_hash(ctx->hash_map);
++	kfree(ctx->cancel_hash);
++	kfree(ctx->dummy_ubuf);
++	kfree(ctx);
++}
++
++static __poll_t io_uring_poll(struct file *file, poll_table *wait)
++{
++	struct io_ring_ctx *ctx = file->private_data;
++	__poll_t mask = 0;
++
++	poll_wait(file, &ctx->poll_wait, wait);
++	/*
++	 * synchronizes with barrier from wq_has_sleeper call in
++	 * io_commit_cqring
++	 */
++	smp_rmb();
++	if (!io_sqring_full(ctx))
++		mask |= EPOLLOUT | EPOLLWRNORM;
++
++	/*
++	 * Don't flush cqring overflow list here, just do a simple check.
++	 * Otherwise there could possible be ABBA deadlock:
++	 *      CPU0                    CPU1
++	 *      ----                    ----
++	 * lock(&ctx->uring_lock);
++	 *                              lock(&ep->mtx);
++	 *                              lock(&ctx->uring_lock);
++	 * lock(&ep->mtx);
++	 *
++	 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
++	 * pushs them to do the flush.
++	 */
++	if (io_cqring_events(ctx) || test_bit(0, &ctx->check_cq_overflow))
++		mask |= EPOLLIN | EPOLLRDNORM;
++
++	return mask;
++}
++
++static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
++{
++	const struct cred *creds;
++
++	creds = xa_erase(&ctx->personalities, id);
++	if (creds) {
++		put_cred(creds);
++		return 0;
++	}
++
++	return -EINVAL;
++}
++
++struct io_tctx_exit {
++	struct callback_head		task_work;
++	struct completion		completion;
++	struct io_ring_ctx		*ctx;
++};
++
++static void io_tctx_exit_cb(struct callback_head *cb)
++{
++	struct io_uring_task *tctx = current->io_uring;
++	struct io_tctx_exit *work;
++
++	work = container_of(cb, struct io_tctx_exit, task_work);
++	/*
++	 * When @in_idle, we're in cancellation and it's racy to remove the
++	 * node. It'll be removed by the end of cancellation, just ignore it.
++	 * tctx can be NULL if the queueing of this task_work raced with
++	 * work cancelation off the exec path.
++	 */
++	if (tctx && !atomic_read(&tctx->in_idle))
++		io_uring_del_tctx_node((unsigned long)work->ctx);
++	complete(&work->completion);
++}
++
++static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
++{
++	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
++
++	return req->ctx == data;
++}
++
++static void io_ring_exit_work(struct work_struct *work)
++{
++	struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
++	unsigned long timeout = jiffies + HZ * 60 * 5;
++	unsigned long interval = HZ / 20;
++	struct io_tctx_exit exit;
++	struct io_tctx_node *node;
++	int ret;
++
++	/*
++	 * If we're doing polled IO and end up having requests being
++	 * submitted async (out-of-line), then completions can come in while
++	 * we're waiting for refs to drop. We need to reap these manually,
++	 * as nobody else will be looking for them.
++	 */
++	do {
++		io_uring_try_cancel_requests(ctx, NULL, true);
++		if (ctx->sq_data) {
++			struct io_sq_data *sqd = ctx->sq_data;
++			struct task_struct *tsk;
++
++			io_sq_thread_park(sqd);
++			tsk = sqd->thread;
++			if (tsk && tsk->io_uring && tsk->io_uring->io_wq)
++				io_wq_cancel_cb(tsk->io_uring->io_wq,
++						io_cancel_ctx_cb, ctx, true);
++			io_sq_thread_unpark(sqd);
++		}
++
++		if (WARN_ON_ONCE(time_after(jiffies, timeout))) {
++			/* there is little hope left, don't run it too often */
++			interval = HZ * 60;
++		}
++	} while (!wait_for_completion_timeout(&ctx->ref_comp, interval));
++
++	init_completion(&exit.completion);
++	init_task_work(&exit.task_work, io_tctx_exit_cb);
++	exit.ctx = ctx;
++	/*
++	 * Some may use context even when all refs and requests have been put,
++	 * and they are free to do so while still holding uring_lock or
++	 * completion_lock, see io_req_task_submit(). Apart from other work,
++	 * this lock/unlock section also waits them to finish.
++	 */
++	mutex_lock(&ctx->uring_lock);
++	while (!list_empty(&ctx->tctx_list)) {
++		WARN_ON_ONCE(time_after(jiffies, timeout));
++
++		node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
++					ctx_node);
++		/* don't spin on a single task if cancellation failed */
++		list_rotate_left(&ctx->tctx_list);
++		ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
++		if (WARN_ON_ONCE(ret))
++			continue;
++		wake_up_process(node->task);
++
++		mutex_unlock(&ctx->uring_lock);
++		wait_for_completion(&exit.completion);
++		mutex_lock(&ctx->uring_lock);
++	}
++	mutex_unlock(&ctx->uring_lock);
++	spin_lock(&ctx->completion_lock);
++	spin_unlock(&ctx->completion_lock);
++
++	io_ring_ctx_free(ctx);
++}
++
++/* Returns true if we found and killed one or more timeouts */
++static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
++			     bool cancel_all)
++{
++	struct io_kiocb *req, *tmp;
++	int canceled = 0;
++
++	spin_lock(&ctx->completion_lock);
++	spin_lock_irq(&ctx->timeout_lock);
++	list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
++		if (io_match_task(req, tsk, cancel_all)) {
++			io_kill_timeout(req, -ECANCELED);
++			canceled++;
++		}
++	}
++	spin_unlock_irq(&ctx->timeout_lock);
++	if (canceled != 0)
++		io_commit_cqring(ctx);
++	spin_unlock(&ctx->completion_lock);
++	if (canceled != 0)
++		io_cqring_ev_posted(ctx);
++	return canceled != 0;
++}
++
++static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
++{
++	unsigned long index;
++	struct creds *creds;
++
++	mutex_lock(&ctx->uring_lock);
++	percpu_ref_kill(&ctx->refs);
++	if (ctx->rings)
++		__io_cqring_overflow_flush(ctx, true);
++	xa_for_each(&ctx->personalities, index, creds)
++		io_unregister_personality(ctx, index);
++	mutex_unlock(&ctx->uring_lock);
++
++	io_kill_timeouts(ctx, NULL, true);
++	io_poll_remove_all(ctx, NULL, true);
++
++	/* if we failed setting up the ctx, we might not have any rings */
++	io_iopoll_try_reap_events(ctx);
++
++	INIT_WORK(&ctx->exit_work, io_ring_exit_work);
++	/*
++	 * Use system_unbound_wq to avoid spawning tons of event kworkers
++	 * if we're exiting a ton of rings at the same time. It just adds
++	 * noise and overhead, there's no discernable change in runtime
++	 * over using system_wq.
++	 */
++	queue_work(system_unbound_wq, &ctx->exit_work);
++}
++
++static int io_uring_release(struct inode *inode, struct file *file)
++{
++	struct io_ring_ctx *ctx = file->private_data;
++
++	file->private_data = NULL;
++	io_ring_ctx_wait_and_kill(ctx);
++	return 0;
++}
++
++struct io_task_cancel {
++	struct task_struct *task;
++	bool all;
++};
++
++static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
++{
++	struct io_kiocb *req = container_of(work, struct io_kiocb, work);
++	struct io_task_cancel *cancel = data;
++
++	return io_match_task_safe(req, cancel->task, cancel->all);
++}
++
++static bool io_cancel_defer_files(struct io_ring_ctx *ctx,
++				  struct task_struct *task, bool cancel_all)
++{
++	struct io_defer_entry *de;
++	LIST_HEAD(list);
++
++	spin_lock(&ctx->completion_lock);
++	list_for_each_entry_reverse(de, &ctx->defer_list, list) {
++		if (io_match_task_safe(de->req, task, cancel_all)) {
++			list_cut_position(&list, &ctx->defer_list, &de->list);
++			break;
++		}
++	}
++	spin_unlock(&ctx->completion_lock);
++	if (list_empty(&list))
++		return false;
++
++	while (!list_empty(&list)) {
++		de = list_first_entry(&list, struct io_defer_entry, list);
++		list_del_init(&de->list);
++		io_req_complete_failed(de->req, -ECANCELED);
++		kfree(de);
++	}
++	return true;
++}
++
++static bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
++{
++	struct io_tctx_node *node;
++	enum io_wq_cancel cret;
++	bool ret = false;
++
++	mutex_lock(&ctx->uring_lock);
++	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
++		struct io_uring_task *tctx = node->task->io_uring;
++
++		/*
++		 * io_wq will stay alive while we hold uring_lock, because it's
++		 * killed after ctx nodes, which requires to take the lock.
++		 */
++		if (!tctx || !tctx->io_wq)
++			continue;
++		cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
++		ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
++	}
++	mutex_unlock(&ctx->uring_lock);
++
++	return ret;
++}
++
++static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
++					 struct task_struct *task,
++					 bool cancel_all)
++{
++	struct io_task_cancel cancel = { .task = task, .all = cancel_all, };
++	struct io_uring_task *tctx = task ? task->io_uring : NULL;
++
++	while (1) {
++		enum io_wq_cancel cret;
++		bool ret = false;
++
++		if (!task) {
++			ret |= io_uring_try_cancel_iowq(ctx);
++		} else if (tctx && tctx->io_wq) {
++			/*
++			 * Cancels requests of all rings, not only @ctx, but
++			 * it's fine as the task is in exit/exec.
++			 */
++			cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
++					       &cancel, true);
++			ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
++		}
++
++		/* SQPOLL thread does its own polling */
++		if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) ||
++		    (ctx->sq_data && ctx->sq_data->thread == current)) {
++			while (!list_empty_careful(&ctx->iopoll_list)) {
++				io_iopoll_try_reap_events(ctx);
++				ret = true;
++			}
++		}
++
++		ret |= io_cancel_defer_files(ctx, task, cancel_all);
++		ret |= io_poll_remove_all(ctx, task, cancel_all);
++		ret |= io_kill_timeouts(ctx, task, cancel_all);
++		if (task)
++			ret |= io_run_task_work();
++		if (!ret)
++			break;
++		cond_resched();
++	}
++}
++
++static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
++{
++	struct io_uring_task *tctx = current->io_uring;
++	struct io_tctx_node *node;
++	int ret;
++
++	if (unlikely(!tctx)) {
++		ret = io_uring_alloc_task_context(current, ctx);
++		if (unlikely(ret))
++			return ret;
++
++		tctx = current->io_uring;
++		if (ctx->iowq_limits_set) {
++			unsigned int limits[2] = { ctx->iowq_limits[0],
++						   ctx->iowq_limits[1], };
++
++			ret = io_wq_max_workers(tctx->io_wq, limits);
++			if (ret)
++				return ret;
++		}
++	}
++	if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
++		node = kmalloc(sizeof(*node), GFP_KERNEL);
++		if (!node)
++			return -ENOMEM;
++		node->ctx = ctx;
++		node->task = current;
++
++		ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
++					node, GFP_KERNEL));
++		if (ret) {
++			kfree(node);
++			return ret;
++		}
++
++		mutex_lock(&ctx->uring_lock);
++		list_add(&node->ctx_node, &ctx->tctx_list);
++		mutex_unlock(&ctx->uring_lock);
++	}
++	tctx->last = ctx;
++	return 0;
++}
++
++/*
++ * Note that this task has used io_uring. We use it for cancelation purposes.
++ */
++static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
++{
++	struct io_uring_task *tctx = current->io_uring;
++
++	if (likely(tctx && tctx->last == ctx))
++		return 0;
++	return __io_uring_add_tctx_node(ctx);
++}
++
++/*
++ * Remove this io_uring_file -> task mapping.
++ */
++static void io_uring_del_tctx_node(unsigned long index)
++{
++	struct io_uring_task *tctx = current->io_uring;
++	struct io_tctx_node *node;
++
++	if (!tctx)
++		return;
++	node = xa_erase(&tctx->xa, index);
++	if (!node)
++		return;
++
++	WARN_ON_ONCE(current != node->task);
++	WARN_ON_ONCE(list_empty(&node->ctx_node));
++
++	mutex_lock(&node->ctx->uring_lock);
++	list_del(&node->ctx_node);
++	mutex_unlock(&node->ctx->uring_lock);
++
++	if (tctx->last == node->ctx)
++		tctx->last = NULL;
++	kfree(node);
++}
++
++static void io_uring_clean_tctx(struct io_uring_task *tctx)
++{
++	struct io_wq *wq = tctx->io_wq;
++	struct io_tctx_node *node;
++	unsigned long index;
++
++	xa_for_each(&tctx->xa, index, node) {
++		io_uring_del_tctx_node(index);
++		cond_resched();
++	}
++	if (wq) {
++		/*
++		 * Must be after io_uring_del_task_file() (removes nodes under
++		 * uring_lock) to avoid race with io_uring_try_cancel_iowq().
++		 */
++		io_wq_put_and_exit(wq);
++		tctx->io_wq = NULL;
++	}
++}
++
++static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
++{
++	if (tracked)
++		return atomic_read(&tctx->inflight_tracked);
++	return percpu_counter_sum(&tctx->inflight);
++}
++
++/*
++ * Find any io_uring ctx that this task has registered or done IO on, and cancel
++ * requests. @sqd should be not-null IFF it's an SQPOLL thread cancellation.
++ */
++static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd)
++{
++	struct io_uring_task *tctx = current->io_uring;
++	struct io_ring_ctx *ctx;
++	s64 inflight;
++	DEFINE_WAIT(wait);
++
++	WARN_ON_ONCE(sqd && sqd->thread != current);
++
++	if (!current->io_uring)
++		return;
++	if (tctx->io_wq)
++		io_wq_exit_start(tctx->io_wq);
++
++	atomic_inc(&tctx->in_idle);
++	do {
++		io_uring_drop_tctx_refs(current);
++		/* read completions before cancelations */
++		inflight = tctx_inflight(tctx, !cancel_all);
++		if (!inflight)
++			break;
++
++		if (!sqd) {
++			struct io_tctx_node *node;
++			unsigned long index;
++
++			xa_for_each(&tctx->xa, index, node) {
++				/* sqpoll task will cancel all its requests */
++				if (node->ctx->sq_data)
++					continue;
++				io_uring_try_cancel_requests(node->ctx, current,
++							     cancel_all);
++			}
++		} else {
++			list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
++				io_uring_try_cancel_requests(ctx, current,
++							     cancel_all);
++		}
++
++		prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE);
++		io_run_task_work();
++		io_uring_drop_tctx_refs(current);
++
++		/*
++		 * If we've seen completions, retry without waiting. This
++		 * avoids a race where a completion comes in before we did
++		 * prepare_to_wait().
++		 */
++		if (inflight == tctx_inflight(tctx, !cancel_all))
++			schedule();
++		finish_wait(&tctx->wait, &wait);
++	} while (1);
++
++	io_uring_clean_tctx(tctx);
++	if (cancel_all) {
++		/*
++		 * We shouldn't run task_works after cancel, so just leave
++		 * ->in_idle set for normal exit.
++		 */
++		atomic_dec(&tctx->in_idle);
++		/* for exec all current's requests should be gone, kill tctx */
++		__io_uring_free(current);
++	}
++}
++
++void __io_uring_cancel(bool cancel_all)
++{
++	io_uring_cancel_generic(cancel_all, NULL);
++}
++
++static void *io_uring_validate_mmap_request(struct file *file,
++					    loff_t pgoff, size_t sz)
++{
++	struct io_ring_ctx *ctx = file->private_data;
++	loff_t offset = pgoff << PAGE_SHIFT;
++	struct page *page;
++	void *ptr;
++
++	switch (offset) {
++	case IORING_OFF_SQ_RING:
++	case IORING_OFF_CQ_RING:
++		ptr = ctx->rings;
++		break;
++	case IORING_OFF_SQES:
++		ptr = ctx->sq_sqes;
++		break;
++	default:
++		return ERR_PTR(-EINVAL);
++	}
++
++	page = virt_to_head_page(ptr);
++	if (sz > page_size(page))
++		return ERR_PTR(-EINVAL);
++
++	return ptr;
++}
++
++#ifdef CONFIG_MMU
++
++static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
++{
++	size_t sz = vma->vm_end - vma->vm_start;
++	unsigned long pfn;
++	void *ptr;
++
++	ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
++	if (IS_ERR(ptr))
++		return PTR_ERR(ptr);
++
++	pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
++	return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
++}
++
++#else /* !CONFIG_MMU */
++
++static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
++{
++	return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
++}
++
++static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
++{
++	return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
++}
++
++static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
++	unsigned long addr, unsigned long len,
++	unsigned long pgoff, unsigned long flags)
++{
++	void *ptr;
++
++	ptr = io_uring_validate_mmap_request(file, pgoff, len);
++	if (IS_ERR(ptr))
++		return PTR_ERR(ptr);
++
++	return (unsigned long) ptr;
++}
++
++#endif /* !CONFIG_MMU */
++
++static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
++{
++	DEFINE_WAIT(wait);
++
++	do {
++		if (!io_sqring_full(ctx))
++			break;
++		prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
++
++		if (!io_sqring_full(ctx))
++			break;
++		schedule();
++	} while (!signal_pending(current));
++
++	finish_wait(&ctx->sqo_sq_wait, &wait);
++	return 0;
++}
++
++static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
++			  struct __kernel_timespec __user **ts,
++			  const sigset_t __user **sig)
++{
++	struct io_uring_getevents_arg arg;
++
++	/*
++	 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
++	 * is just a pointer to the sigset_t.
++	 */
++	if (!(flags & IORING_ENTER_EXT_ARG)) {
++		*sig = (const sigset_t __user *) argp;
++		*ts = NULL;
++		return 0;
++	}
++
++	/*
++	 * EXT_ARG is set - ensure we agree on the size of it and copy in our
++	 * timespec and sigset_t pointers if good.
++	 */
++	if (*argsz != sizeof(arg))
++		return -EINVAL;
++	if (copy_from_user(&arg, argp, sizeof(arg)))
++		return -EFAULT;
++	if (arg.pad)
++		return -EINVAL;
++	*sig = u64_to_user_ptr(arg.sigmask);
++	*argsz = arg.sigmask_sz;
++	*ts = u64_to_user_ptr(arg.ts);
++	return 0;
++}
++
++SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
++		u32, min_complete, u32, flags, const void __user *, argp,
++		size_t, argsz)
++{
++	struct io_ring_ctx *ctx;
++	int submitted = 0;
++	struct fd f;
++	long ret;
++
++	io_run_task_work();
++
++	if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
++			       IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG)))
++		return -EINVAL;
++
++	f = fdget(fd);
++	if (unlikely(!f.file))
++		return -EBADF;
++
++	ret = -EOPNOTSUPP;
++	if (unlikely(f.file->f_op != &io_uring_fops))
++		goto out_fput;
++
++	ret = -ENXIO;
++	ctx = f.file->private_data;
++	if (unlikely(!percpu_ref_tryget(&ctx->refs)))
++		goto out_fput;
++
++	ret = -EBADFD;
++	if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED))
++		goto out;
++
++	/*
++	 * For SQ polling, the thread will do all submissions and completions.
++	 * Just return the requested submit count, and wake the thread if
++	 * we were asked to.
++	 */
++	ret = 0;
++	if (ctx->flags & IORING_SETUP_SQPOLL) {
++		io_cqring_overflow_flush(ctx);
++
++		if (unlikely(ctx->sq_data->thread == NULL)) {
++			ret = -EOWNERDEAD;
++			goto out;
++		}
++		if (flags & IORING_ENTER_SQ_WAKEUP)
++			wake_up(&ctx->sq_data->wait);
++		if (flags & IORING_ENTER_SQ_WAIT) {
++			ret = io_sqpoll_wait_sq(ctx);
++			if (ret)
++				goto out;
++		}
++		submitted = to_submit;
++	} else if (to_submit) {
++		ret = io_uring_add_tctx_node(ctx);
++		if (unlikely(ret))
++			goto out;
++		mutex_lock(&ctx->uring_lock);
++		submitted = io_submit_sqes(ctx, to_submit);
++		mutex_unlock(&ctx->uring_lock);
++
++		if (submitted != to_submit)
++			goto out;
++	}
++	if (flags & IORING_ENTER_GETEVENTS) {
++		const sigset_t __user *sig;
++		struct __kernel_timespec __user *ts;
++
++		ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
++		if (unlikely(ret))
++			goto out;
++
++		min_complete = min(min_complete, ctx->cq_entries);
++
++		/*
++		 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
++		 * space applications don't need to do io completion events
++		 * polling again, they can rely on io_sq_thread to do polling
++		 * work, which can reduce cpu usage and uring_lock contention.
++		 */
++		if (ctx->flags & IORING_SETUP_IOPOLL &&
++		    !(ctx->flags & IORING_SETUP_SQPOLL)) {
++			ret = io_iopoll_check(ctx, min_complete);
++		} else {
++			ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts);
++		}
++	}
++
++out:
++	percpu_ref_put(&ctx->refs);
++out_fput:
++	fdput(f);
++	return submitted ? submitted : ret;
++}
++
++#ifdef CONFIG_PROC_FS
++static int io_uring_show_cred(struct seq_file *m, unsigned int id,
++		const struct cred *cred)
++{
++	struct user_namespace *uns = seq_user_ns(m);
++	struct group_info *gi;
++	kernel_cap_t cap;
++	unsigned __capi;
++	int g;
++
++	seq_printf(m, "%5d\n", id);
++	seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
++	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
++	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
++	seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
++	seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
++	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
++	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
++	seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
++	seq_puts(m, "\n\tGroups:\t");
++	gi = cred->group_info;
++	for (g = 0; g < gi->ngroups; g++) {
++		seq_put_decimal_ull(m, g ? " " : "",
++					from_kgid_munged(uns, gi->gid[g]));
++	}
++	seq_puts(m, "\n\tCapEff:\t");
++	cap = cred->cap_effective;
++	CAP_FOR_EACH_U32(__capi)
++		seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
++	seq_putc(m, '\n');
++	return 0;
++}
++
++static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
++{
++	struct io_sq_data *sq = NULL;
++	bool has_lock;
++	int i;
++
++	/*
++	 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
++	 * since fdinfo case grabs it in the opposite direction of normal use
++	 * cases. If we fail to get the lock, we just don't iterate any
++	 * structures that could be going away outside the io_uring mutex.
++	 */
++	has_lock = mutex_trylock(&ctx->uring_lock);
++
++	if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
++		sq = ctx->sq_data;
++		if (!sq->thread)
++			sq = NULL;
++	}
++
++	seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
++	seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
++	seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
++	for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
++		struct file *f = io_file_from_index(ctx, i);
++
++		if (f)
++			seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
++		else
++			seq_printf(m, "%5u: <none>\n", i);
++	}
++	seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
++	for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
++		struct io_mapped_ubuf *buf = ctx->user_bufs[i];
++		unsigned int len = buf->ubuf_end - buf->ubuf;
++
++		seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
++	}
++	if (has_lock && !xa_empty(&ctx->personalities)) {
++		unsigned long index;
++		const struct cred *cred;
++
++		seq_printf(m, "Personalities:\n");
++		xa_for_each(&ctx->personalities, index, cred)
++			io_uring_show_cred(m, index, cred);
++	}
++	seq_printf(m, "PollList:\n");
++	spin_lock(&ctx->completion_lock);
++	for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
++		struct hlist_head *list = &ctx->cancel_hash[i];
++		struct io_kiocb *req;
++
++		hlist_for_each_entry(req, list, hash_node)
++			seq_printf(m, "  op=%d, task_works=%d\n", req->opcode,
++					req->task->task_works != NULL);
++	}
++	spin_unlock(&ctx->completion_lock);
++	if (has_lock)
++		mutex_unlock(&ctx->uring_lock);
++}
++
++static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
++{
++	struct io_ring_ctx *ctx = f->private_data;
++
++	if (percpu_ref_tryget(&ctx->refs)) {
++		__io_uring_show_fdinfo(ctx, m);
++		percpu_ref_put(&ctx->refs);
++	}
++}
++#endif
++
++static const struct file_operations io_uring_fops = {
++	.release	= io_uring_release,
++	.mmap		= io_uring_mmap,
++#ifndef CONFIG_MMU
++	.get_unmapped_area = io_uring_nommu_get_unmapped_area,
++	.mmap_capabilities = io_uring_nommu_mmap_capabilities,
++#endif
++	.poll		= io_uring_poll,
++#ifdef CONFIG_PROC_FS
++	.show_fdinfo	= io_uring_show_fdinfo,
++#endif
++};
++
++static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
++				  struct io_uring_params *p)
++{
++	struct io_rings *rings;
++	size_t size, sq_array_offset;
++
++	/* make sure these are sane, as we already accounted them */
++	ctx->sq_entries = p->sq_entries;
++	ctx->cq_entries = p->cq_entries;
++
++	size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
++	if (size == SIZE_MAX)
++		return -EOVERFLOW;
++
++	rings = io_mem_alloc(size);
++	if (!rings)
++		return -ENOMEM;
++
++	ctx->rings = rings;
++	ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
++	rings->sq_ring_mask = p->sq_entries - 1;
++	rings->cq_ring_mask = p->cq_entries - 1;
++	rings->sq_ring_entries = p->sq_entries;
++	rings->cq_ring_entries = p->cq_entries;
++
++	size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
++	if (size == SIZE_MAX) {
++		io_mem_free(ctx->rings);
++		ctx->rings = NULL;
++		return -EOVERFLOW;
++	}
++
++	ctx->sq_sqes = io_mem_alloc(size);
++	if (!ctx->sq_sqes) {
++		io_mem_free(ctx->rings);
++		ctx->rings = NULL;
++		return -ENOMEM;
++	}
++
++	return 0;
++}
++
++static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
++{
++	int ret, fd;
++
++	fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
++	if (fd < 0)
++		return fd;
++
++	ret = io_uring_add_tctx_node(ctx);
++	if (ret) {
++		put_unused_fd(fd);
++		return ret;
++	}
++	fd_install(fd, file);
++	return fd;
++}
++
++/*
++ * Allocate an anonymous fd, this is what constitutes the application
++ * visible backing of an io_uring instance. The application mmaps this
++ * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
++ * we have to tie this fd to a socket for file garbage collection purposes.
++ */
++static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
++{
++	struct file *file;
++#if defined(CONFIG_UNIX)
++	int ret;
++
++	ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
++				&ctx->ring_sock);
++	if (ret)
++		return ERR_PTR(ret);
++#endif
++
++	file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
++					O_RDWR | O_CLOEXEC);
++#if defined(CONFIG_UNIX)
++	if (IS_ERR(file)) {
++		sock_release(ctx->ring_sock);
++		ctx->ring_sock = NULL;
++	} else {
++		ctx->ring_sock->file = file;
++	}
++#endif
++	return file;
++}
++
++static int io_uring_create(unsigned entries, struct io_uring_params *p,
++			   struct io_uring_params __user *params)
++{
++	struct io_ring_ctx *ctx;
++	struct file *file;
++	int ret;
++
++	if (!entries)
++		return -EINVAL;
++	if (entries > IORING_MAX_ENTRIES) {
++		if (!(p->flags & IORING_SETUP_CLAMP))
++			return -EINVAL;
++		entries = IORING_MAX_ENTRIES;
++	}
++
++	/*
++	 * Use twice as many entries for the CQ ring. It's possible for the
++	 * application to drive a higher depth than the size of the SQ ring,
++	 * since the sqes are only used at submission time. This allows for
++	 * some flexibility in overcommitting a bit. If the application has
++	 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
++	 * of CQ ring entries manually.
++	 */
++	p->sq_entries = roundup_pow_of_two(entries);
++	if (p->flags & IORING_SETUP_CQSIZE) {
++		/*
++		 * If IORING_SETUP_CQSIZE is set, we do the same roundup
++		 * to a power-of-two, if it isn't already. We do NOT impose
++		 * any cq vs sq ring sizing.
++		 */
++		if (!p->cq_entries)
++			return -EINVAL;
++		if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
++			if (!(p->flags & IORING_SETUP_CLAMP))
++				return -EINVAL;
++			p->cq_entries = IORING_MAX_CQ_ENTRIES;
++		}
++		p->cq_entries = roundup_pow_of_two(p->cq_entries);
++		if (p->cq_entries < p->sq_entries)
++			return -EINVAL;
++	} else {
++		p->cq_entries = 2 * p->sq_entries;
++	}
++
++	ctx = io_ring_ctx_alloc(p);
++	if (!ctx)
++		return -ENOMEM;
++	ctx->compat = in_compat_syscall();
++	if (!capable(CAP_IPC_LOCK))
++		ctx->user = get_uid(current_user());
++
++	/*
++	 * This is just grabbed for accounting purposes. When a process exits,
++	 * the mm is exited and dropped before the files, hence we need to hang
++	 * on to this mm purely for the purposes of being able to unaccount
++	 * memory (locked/pinned vm). It's not used for anything else.
++	 */
++	mmgrab(current->mm);
++	ctx->mm_account = current->mm;
++
++	ret = io_allocate_scq_urings(ctx, p);
++	if (ret)
++		goto err;
++
++	ret = io_sq_offload_create(ctx, p);
++	if (ret)
++		goto err;
++	/* always set a rsrc node */
++	ret = io_rsrc_node_switch_start(ctx);
++	if (ret)
++		goto err;
++	io_rsrc_node_switch(ctx, NULL);
++
++	memset(&p->sq_off, 0, sizeof(p->sq_off));
++	p->sq_off.head = offsetof(struct io_rings, sq.head);
++	p->sq_off.tail = offsetof(struct io_rings, sq.tail);
++	p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
++	p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
++	p->sq_off.flags = offsetof(struct io_rings, sq_flags);
++	p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
++	p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
++
++	memset(&p->cq_off, 0, sizeof(p->cq_off));
++	p->cq_off.head = offsetof(struct io_rings, cq.head);
++	p->cq_off.tail = offsetof(struct io_rings, cq.tail);
++	p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
++	p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
++	p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
++	p->cq_off.cqes = offsetof(struct io_rings, cqes);
++	p->cq_off.flags = offsetof(struct io_rings, cq_flags);
++
++	p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
++			IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
++			IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
++			IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
++			IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS |
++			IORING_FEAT_RSRC_TAGS;
++
++	if (copy_to_user(params, p, sizeof(*p))) {
++		ret = -EFAULT;
++		goto err;
++	}
++
++	file = io_uring_get_file(ctx);
++	if (IS_ERR(file)) {
++		ret = PTR_ERR(file);
++		goto err;
++	}
++
++	/*
++	 * Install ring fd as the very last thing, so we don't risk someone
++	 * having closed it before we finish setup
++	 */
++	ret = io_uring_install_fd(ctx, file);
++	if (ret < 0) {
++		/* fput will clean it up */
++		fput(file);
++		return ret;
++	}
++
++	trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
++	return ret;
++err:
++	io_ring_ctx_wait_and_kill(ctx);
++	return ret;
++}
++
++/*
++ * Sets up an aio uring context, and returns the fd. Applications asks for a
++ * ring size, we return the actual sq/cq ring sizes (among other things) in the
++ * params structure passed in.
++ */
++static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
++{
++	struct io_uring_params p;
++	int i;
++
++	if (copy_from_user(&p, params, sizeof(p)))
++		return -EFAULT;
++	for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
++		if (p.resv[i])
++			return -EINVAL;
++	}
++
++	if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
++			IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
++			IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
++			IORING_SETUP_R_DISABLED))
++		return -EINVAL;
++
++	return  io_uring_create(entries, &p, params);
++}
++
++SYSCALL_DEFINE2(io_uring_setup, u32, entries,
++		struct io_uring_params __user *, params)
++{
++	return io_uring_setup(entries, params);
++}
++
++static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
++{
++	struct io_uring_probe *p;
++	size_t size;
++	int i, ret;
++
++	size = struct_size(p, ops, nr_args);
++	if (size == SIZE_MAX)
++		return -EOVERFLOW;
++	p = kzalloc(size, GFP_KERNEL);
++	if (!p)
++		return -ENOMEM;
++
++	ret = -EFAULT;
++	if (copy_from_user(p, arg, size))
++		goto out;
++	ret = -EINVAL;
++	if (memchr_inv(p, 0, size))
++		goto out;
++
++	p->last_op = IORING_OP_LAST - 1;
++	if (nr_args > IORING_OP_LAST)
++		nr_args = IORING_OP_LAST;
++
++	for (i = 0; i < nr_args; i++) {
++		p->ops[i].op = i;
++		if (!io_op_defs[i].not_supported)
++			p->ops[i].flags = IO_URING_OP_SUPPORTED;
++	}
++	p->ops_len = i;
++
++	ret = 0;
++	if (copy_to_user(arg, p, size))
++		ret = -EFAULT;
++out:
++	kfree(p);
++	return ret;
++}
++
++static int io_register_personality(struct io_ring_ctx *ctx)
++{
++	const struct cred *creds;
++	u32 id;
++	int ret;
++
++	creds = get_current_cred();
++
++	ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
++			XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
++	if (ret < 0) {
++		put_cred(creds);
++		return ret;
++	}
++	return id;
++}
++
++static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
++				    unsigned int nr_args)
++{
++	struct io_uring_restriction *res;
++	size_t size;
++	int i, ret;
++
++	/* Restrictions allowed only if rings started disabled */
++	if (!(ctx->flags & IORING_SETUP_R_DISABLED))
++		return -EBADFD;
++
++	/* We allow only a single restrictions registration */
++	if (ctx->restrictions.registered)
++		return -EBUSY;
++
++	if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
++		return -EINVAL;
++
++	size = array_size(nr_args, sizeof(*res));
++	if (size == SIZE_MAX)
++		return -EOVERFLOW;
++
++	res = memdup_user(arg, size);
++	if (IS_ERR(res))
++		return PTR_ERR(res);
++
++	ret = 0;
++
++	for (i = 0; i < nr_args; i++) {
++		switch (res[i].opcode) {
++		case IORING_RESTRICTION_REGISTER_OP:
++			if (res[i].register_op >= IORING_REGISTER_LAST) {
++				ret = -EINVAL;
++				goto out;
++			}
++
++			__set_bit(res[i].register_op,
++				  ctx->restrictions.register_op);
++			break;
++		case IORING_RESTRICTION_SQE_OP:
++			if (res[i].sqe_op >= IORING_OP_LAST) {
++				ret = -EINVAL;
++				goto out;
++			}
++
++			__set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
++			break;
++		case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
++			ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
++			break;
++		case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
++			ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
++			break;
++		default:
++			ret = -EINVAL;
++			goto out;
++		}
++	}
++
++out:
++	/* Reset all restrictions if an error happened */
++	if (ret != 0)
++		memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
++	else
++		ctx->restrictions.registered = true;
++
++	kfree(res);
++	return ret;
++}
++
++static int io_register_enable_rings(struct io_ring_ctx *ctx)
++{
++	if (!(ctx->flags & IORING_SETUP_R_DISABLED))
++		return -EBADFD;
++
++	if (ctx->restrictions.registered)
++		ctx->restricted = 1;
++
++	ctx->flags &= ~IORING_SETUP_R_DISABLED;
++	if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
++		wake_up(&ctx->sq_data->wait);
++	return 0;
++}
++
++static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
++				     struct io_uring_rsrc_update2 *up,
++				     unsigned nr_args)
++{
++	__u32 tmp;
++	int err;
++
++	if (check_add_overflow(up->offset, nr_args, &tmp))
++		return -EOVERFLOW;
++	err = io_rsrc_node_switch_start(ctx);
++	if (err)
++		return err;
++
++	switch (type) {
++	case IORING_RSRC_FILE:
++		return __io_sqe_files_update(ctx, up, nr_args);
++	case IORING_RSRC_BUFFER:
++		return __io_sqe_buffers_update(ctx, up, nr_args);
++	}
++	return -EINVAL;
++}
++
++static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
++				    unsigned nr_args)
++{
++	struct io_uring_rsrc_update2 up;
++
++	if (!nr_args)
++		return -EINVAL;
++	memset(&up, 0, sizeof(up));
++	if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update)))
++		return -EFAULT;
++	if (up.resv || up.resv2)
++		return -EINVAL;
++	return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args);
++}
++
++static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
++				   unsigned size, unsigned type)
++{
++	struct io_uring_rsrc_update2 up;
++
++	if (size != sizeof(up))
++		return -EINVAL;
++	if (copy_from_user(&up, arg, sizeof(up)))
++		return -EFAULT;
++	if (!up.nr || up.resv || up.resv2)
++		return -EINVAL;
++	return __io_register_rsrc_update(ctx, type, &up, up.nr);
++}
++
++static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
++			    unsigned int size, unsigned int type)
++{
++	struct io_uring_rsrc_register rr;
++
++	/* keep it extendible */
++	if (size != sizeof(rr))
++		return -EINVAL;
++
++	memset(&rr, 0, sizeof(rr));
++	if (copy_from_user(&rr, arg, size))
++		return -EFAULT;
++	if (!rr.nr || rr.resv || rr.resv2)
++		return -EINVAL;
++
++	switch (type) {
++	case IORING_RSRC_FILE:
++		return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data),
++					     rr.nr, u64_to_user_ptr(rr.tags));
++	case IORING_RSRC_BUFFER:
++		return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data),
++					       rr.nr, u64_to_user_ptr(rr.tags));
++	}
++	return -EINVAL;
++}
++
++static int io_register_iowq_aff(struct io_ring_ctx *ctx, void __user *arg,
++				unsigned len)
++{
++	struct io_uring_task *tctx = current->io_uring;
++	cpumask_var_t new_mask;
++	int ret;
++
++	if (!tctx || !tctx->io_wq)
++		return -EINVAL;
++
++	if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
++		return -ENOMEM;
++
++	cpumask_clear(new_mask);
++	if (len > cpumask_size())
++		len = cpumask_size();
++
++	if (in_compat_syscall()) {
++		ret = compat_get_bitmap(cpumask_bits(new_mask),
++					(const compat_ulong_t __user *)arg,
++					len * 8 /* CHAR_BIT */);
++	} else {
++		ret = copy_from_user(new_mask, arg, len);
++	}
++
++	if (ret) {
++		free_cpumask_var(new_mask);
++		return -EFAULT;
++	}
++
++	ret = io_wq_cpu_affinity(tctx->io_wq, new_mask);
++	free_cpumask_var(new_mask);
++	return ret;
++}
++
++static int io_unregister_iowq_aff(struct io_ring_ctx *ctx)
++{
++	struct io_uring_task *tctx = current->io_uring;
++
++	if (!tctx || !tctx->io_wq)
++		return -EINVAL;
++
++	return io_wq_cpu_affinity(tctx->io_wq, NULL);
++}
++
++static int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
++					void __user *arg)
++	__must_hold(&ctx->uring_lock)
++{
++	struct io_tctx_node *node;
++	struct io_uring_task *tctx = NULL;
++	struct io_sq_data *sqd = NULL;
++	__u32 new_count[2];
++	int i, ret;
++
++	if (copy_from_user(new_count, arg, sizeof(new_count)))
++		return -EFAULT;
++	for (i = 0; i < ARRAY_SIZE(new_count); i++)
++		if (new_count[i] > INT_MAX)
++			return -EINVAL;
++
++	if (ctx->flags & IORING_SETUP_SQPOLL) {
++		sqd = ctx->sq_data;
++		if (sqd) {
++			/*
++			 * Observe the correct sqd->lock -> ctx->uring_lock
++			 * ordering. Fine to drop uring_lock here, we hold
++			 * a ref to the ctx.
++			 */
++			refcount_inc(&sqd->refs);
++			mutex_unlock(&ctx->uring_lock);
++			mutex_lock(&sqd->lock);
++			mutex_lock(&ctx->uring_lock);
++			if (sqd->thread)
++				tctx = sqd->thread->io_uring;
++		}
++	} else {
++		tctx = current->io_uring;
++	}
++
++	BUILD_BUG_ON(sizeof(new_count) != sizeof(ctx->iowq_limits));
++
++	for (i = 0; i < ARRAY_SIZE(new_count); i++)
++		if (new_count[i])
++			ctx->iowq_limits[i] = new_count[i];
++	ctx->iowq_limits_set = true;
++
++	ret = -EINVAL;
++	if (tctx && tctx->io_wq) {
++		ret = io_wq_max_workers(tctx->io_wq, new_count);
++		if (ret)
++			goto err;
++	} else {
++		memset(new_count, 0, sizeof(new_count));
++	}
++
++	if (sqd) {
++		mutex_unlock(&sqd->lock);
++		io_put_sq_data(sqd);
++	}
++
++	if (copy_to_user(arg, new_count, sizeof(new_count)))
++		return -EFAULT;
++
++	/* that's it for SQPOLL, only the SQPOLL task creates requests */
++	if (sqd)
++		return 0;
++
++	/* now propagate the restriction to all registered users */
++	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
++		struct io_uring_task *tctx = node->task->io_uring;
++
++		if (WARN_ON_ONCE(!tctx->io_wq))
++			continue;
++
++		for (i = 0; i < ARRAY_SIZE(new_count); i++)
++			new_count[i] = ctx->iowq_limits[i];
++		/* ignore errors, it always returns zero anyway */
++		(void)io_wq_max_workers(tctx->io_wq, new_count);
++	}
++	return 0;
++err:
++	if (sqd) {
++		mutex_unlock(&sqd->lock);
++		io_put_sq_data(sqd);
++	}
++	return ret;
++}
++
++static bool io_register_op_must_quiesce(int op)
++{
++	switch (op) {
++	case IORING_REGISTER_BUFFERS:
++	case IORING_UNREGISTER_BUFFERS:
++	case IORING_REGISTER_FILES:
++	case IORING_UNREGISTER_FILES:
++	case IORING_REGISTER_FILES_UPDATE:
++	case IORING_REGISTER_PROBE:
++	case IORING_REGISTER_PERSONALITY:
++	case IORING_UNREGISTER_PERSONALITY:
++	case IORING_REGISTER_FILES2:
++	case IORING_REGISTER_FILES_UPDATE2:
++	case IORING_REGISTER_BUFFERS2:
++	case IORING_REGISTER_BUFFERS_UPDATE:
++	case IORING_REGISTER_IOWQ_AFF:
++	case IORING_UNREGISTER_IOWQ_AFF:
++	case IORING_REGISTER_IOWQ_MAX_WORKERS:
++		return false;
++	default:
++		return true;
++	}
++}
++
++static int io_ctx_quiesce(struct io_ring_ctx *ctx)
++{
++	long ret;
++
++	percpu_ref_kill(&ctx->refs);
++
++	/*
++	 * Drop uring mutex before waiting for references to exit. If another
++	 * thread is currently inside io_uring_enter() it might need to grab the
++	 * uring_lock to make progress. If we hold it here across the drain
++	 * wait, then we can deadlock. It's safe to drop the mutex here, since
++	 * no new references will come in after we've killed the percpu ref.
++	 */
++	mutex_unlock(&ctx->uring_lock);
++	do {
++		ret = wait_for_completion_interruptible(&ctx->ref_comp);
++		if (!ret)
++			break;
++		ret = io_run_task_work_sig();
++	} while (ret >= 0);
++	mutex_lock(&ctx->uring_lock);
++
++	if (ret)
++		io_refs_resurrect(&ctx->refs, &ctx->ref_comp);
++	return ret;
++}
++
++static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
++			       void __user *arg, unsigned nr_args)
++	__releases(ctx->uring_lock)
++	__acquires(ctx->uring_lock)
++{
++	int ret;
++
++	/*
++	 * We're inside the ring mutex, if the ref is already dying, then
++	 * someone else killed the ctx or is already going through
++	 * io_uring_register().
++	 */
++	if (percpu_ref_is_dying(&ctx->refs))
++		return -ENXIO;
++
++	if (ctx->restricted) {
++		if (opcode >= IORING_REGISTER_LAST)
++			return -EINVAL;
++		opcode = array_index_nospec(opcode, IORING_REGISTER_LAST);
++		if (!test_bit(opcode, ctx->restrictions.register_op))
++			return -EACCES;
++	}
++
++	if (io_register_op_must_quiesce(opcode)) {
++		ret = io_ctx_quiesce(ctx);
++		if (ret)
++			return ret;
++	}
++
++	switch (opcode) {
++	case IORING_REGISTER_BUFFERS:
++		ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL);
++		break;
++	case IORING_UNREGISTER_BUFFERS:
++		ret = -EINVAL;
++		if (arg || nr_args)
++			break;
++		ret = io_sqe_buffers_unregister(ctx);
++		break;
++	case IORING_REGISTER_FILES:
++		ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
++		break;
++	case IORING_UNREGISTER_FILES:
++		ret = -EINVAL;
++		if (arg || nr_args)
++			break;
++		ret = io_sqe_files_unregister(ctx);
++		break;
++	case IORING_REGISTER_FILES_UPDATE:
++		ret = io_register_files_update(ctx, arg, nr_args);
++		break;
++	case IORING_REGISTER_EVENTFD:
++	case IORING_REGISTER_EVENTFD_ASYNC:
++		ret = -EINVAL;
++		if (nr_args != 1)
++			break;
++		ret = io_eventfd_register(ctx, arg);
++		if (ret)
++			break;
++		if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
++			ctx->eventfd_async = 1;
++		else
++			ctx->eventfd_async = 0;
++		break;
++	case IORING_UNREGISTER_EVENTFD:
++		ret = -EINVAL;
++		if (arg || nr_args)
++			break;
++		ret = io_eventfd_unregister(ctx);
++		break;
++	case IORING_REGISTER_PROBE:
++		ret = -EINVAL;
++		if (!arg || nr_args > 256)
++			break;
++		ret = io_probe(ctx, arg, nr_args);
++		break;
++	case IORING_REGISTER_PERSONALITY:
++		ret = -EINVAL;
++		if (arg || nr_args)
++			break;
++		ret = io_register_personality(ctx);
++		break;
++	case IORING_UNREGISTER_PERSONALITY:
++		ret = -EINVAL;
++		if (arg)
++			break;
++		ret = io_unregister_personality(ctx, nr_args);
++		break;
++	case IORING_REGISTER_ENABLE_RINGS:
++		ret = -EINVAL;
++		if (arg || nr_args)
++			break;
++		ret = io_register_enable_rings(ctx);
++		break;
++	case IORING_REGISTER_RESTRICTIONS:
++		ret = io_register_restrictions(ctx, arg, nr_args);
++		break;
++	case IORING_REGISTER_FILES2:
++		ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE);
++		break;
++	case IORING_REGISTER_FILES_UPDATE2:
++		ret = io_register_rsrc_update(ctx, arg, nr_args,
++					      IORING_RSRC_FILE);
++		break;
++	case IORING_REGISTER_BUFFERS2:
++		ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER);
++		break;
++	case IORING_REGISTER_BUFFERS_UPDATE:
++		ret = io_register_rsrc_update(ctx, arg, nr_args,
++					      IORING_RSRC_BUFFER);
++		break;
++	case IORING_REGISTER_IOWQ_AFF:
++		ret = -EINVAL;
++		if (!arg || !nr_args)
++			break;
++		ret = io_register_iowq_aff(ctx, arg, nr_args);
++		break;
++	case IORING_UNREGISTER_IOWQ_AFF:
++		ret = -EINVAL;
++		if (arg || nr_args)
++			break;
++		ret = io_unregister_iowq_aff(ctx);
++		break;
++	case IORING_REGISTER_IOWQ_MAX_WORKERS:
++		ret = -EINVAL;
++		if (!arg || nr_args != 2)
++			break;
++		ret = io_register_iowq_max_workers(ctx, arg);
++		break;
++	default:
++		ret = -EINVAL;
++		break;
++	}
++
++	if (io_register_op_must_quiesce(opcode)) {
++		/* bring the ctx back to life */
++		percpu_ref_reinit(&ctx->refs);
++		reinit_completion(&ctx->ref_comp);
++	}
++	return ret;
++}
++
++SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
++		void __user *, arg, unsigned int, nr_args)
++{
++	struct io_ring_ctx *ctx;
++	long ret = -EBADF;
++	struct fd f;
++
++	f = fdget(fd);
++	if (!f.file)
++		return -EBADF;
++
++	ret = -EOPNOTSUPP;
++	if (f.file->f_op != &io_uring_fops)
++		goto out_fput;
++
++	ctx = f.file->private_data;
++
++	io_run_task_work();
++
++	mutex_lock(&ctx->uring_lock);
++	ret = __io_uring_register(ctx, opcode, arg, nr_args);
++	mutex_unlock(&ctx->uring_lock);
++	trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
++							ctx->cq_ev_fd != NULL, ret);
++out_fput:
++	fdput(f);
++	return ret;
++}
++
++static int __init io_uring_init(void)
++{
++#define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
++	BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
++	BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
++} while (0)
++
++#define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
++	__BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
++	BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
++	BUILD_BUG_SQE_ELEM(0,  __u8,   opcode);
++	BUILD_BUG_SQE_ELEM(1,  __u8,   flags);
++	BUILD_BUG_SQE_ELEM(2,  __u16,  ioprio);
++	BUILD_BUG_SQE_ELEM(4,  __s32,  fd);
++	BUILD_BUG_SQE_ELEM(8,  __u64,  off);
++	BUILD_BUG_SQE_ELEM(8,  __u64,  addr2);
++	BUILD_BUG_SQE_ELEM(16, __u64,  addr);
++	BUILD_BUG_SQE_ELEM(16, __u64,  splice_off_in);
++	BUILD_BUG_SQE_ELEM(24, __u32,  len);
++	BUILD_BUG_SQE_ELEM(28,     __kernel_rwf_t, rw_flags);
++	BUILD_BUG_SQE_ELEM(28, /* compat */   int, rw_flags);
++	BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
++	BUILD_BUG_SQE_ELEM(28, __u32,  fsync_flags);
++	BUILD_BUG_SQE_ELEM(28, /* compat */ __u16,  poll_events);
++	BUILD_BUG_SQE_ELEM(28, __u32,  poll32_events);
++	BUILD_BUG_SQE_ELEM(28, __u32,  sync_range_flags);
++	BUILD_BUG_SQE_ELEM(28, __u32,  msg_flags);
++	BUILD_BUG_SQE_ELEM(28, __u32,  timeout_flags);
++	BUILD_BUG_SQE_ELEM(28, __u32,  accept_flags);
++	BUILD_BUG_SQE_ELEM(28, __u32,  cancel_flags);
++	BUILD_BUG_SQE_ELEM(28, __u32,  open_flags);
++	BUILD_BUG_SQE_ELEM(28, __u32,  statx_flags);
++	BUILD_BUG_SQE_ELEM(28, __u32,  fadvise_advice);
++	BUILD_BUG_SQE_ELEM(28, __u32,  splice_flags);
++	BUILD_BUG_SQE_ELEM(32, __u64,  user_data);
++	BUILD_BUG_SQE_ELEM(40, __u16,  buf_index);
++	BUILD_BUG_SQE_ELEM(40, __u16,  buf_group);
++	BUILD_BUG_SQE_ELEM(42, __u16,  personality);
++	BUILD_BUG_SQE_ELEM(44, __s32,  splice_fd_in);
++	BUILD_BUG_SQE_ELEM(44, __u32,  file_index);
++
++	BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=
++		     sizeof(struct io_uring_rsrc_update));
++	BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) >
++		     sizeof(struct io_uring_rsrc_update2));
++
++	/* ->buf_index is u16 */
++	BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16));
++
++	/* should fit into one byte */
++	BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));
++
++	BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
++	BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int));
++
++	req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
++				SLAB_ACCOUNT);
++	return 0;
++};
++__initcall(io_uring_init);
+diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
+index 6e36e854b5124..d8fcc139ac05d 100644
+--- a/kernel/cgroup/cgroup-internal.h
++++ b/kernel/cgroup/cgroup-internal.h
+@@ -169,7 +169,6 @@ extern struct mutex cgroup_mutex;
+ extern spinlock_t css_set_lock;
+ extern struct cgroup_subsys *cgroup_subsys[];
+ extern struct list_head cgroup_roots;
+-extern struct file_system_type cgroup_fs_type;
+ 
+ /* iterate across the hierarchies */
+ #define for_each_root(root)						\
+diff --git a/kernel/sched/core.c b/kernel/sched/core.c
+index 85be684687b08..bb684fe1b96ed 100644
+--- a/kernel/sched/core.c
++++ b/kernel/sched/core.c
+@@ -21,7 +21,7 @@
+ #include <asm/tlb.h>
+ 
+ #include "../workqueue_internal.h"
+-#include "../../fs/io-wq.h"
++#include "../../io_uring/io-wq.h"
+ #include "../smpboot.h"
+ 
+ #include "pelt.h"
+diff --git a/mm/gup.c b/mm/gup.c
+index 69e45cbe58f8c..2370565a81dc3 100644
+--- a/mm/gup.c
++++ b/mm/gup.c
+@@ -2721,7 +2721,7 @@ static int gup_pud_range(p4d_t *p4dp, p4d_t p4d, unsigned long addr, unsigned lo
+ 		next = pud_addr_end(addr, end);
+ 		if (unlikely(!pud_present(pud)))
+ 			return 0;
+-		if (unlikely(pud_huge(pud))) {
++		if (unlikely(pud_huge(pud) || pud_devmap(pud))) {
+ 			if (!gup_huge_pud(pud, pudp, addr, next, flags,
+ 					  pages, nr))
+ 				return 0;
+diff --git a/mm/khugepaged.c b/mm/khugepaged.c
+index dd069afd9cb9c..fd25d12e85b33 100644
+--- a/mm/khugepaged.c
++++ b/mm/khugepaged.c
+@@ -1156,6 +1156,7 @@ static void collapse_huge_page(struct mm_struct *mm,
+ 	_pmd = pmdp_collapse_flush(vma, address, pmd);
+ 	spin_unlock(pmd_ptl);
+ 	mmu_notifier_invalidate_range_end(&range);
++	tlb_remove_table_sync_one();
+ 
+ 	spin_lock(pte_ptl);
+ 	isolated = __collapse_huge_page_isolate(vma, address, pte,
+@@ -1442,6 +1443,7 @@ void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr)
+ 	spinlock_t *ptl;
+ 	int count = 0;
+ 	int i;
++	struct mmu_notifier_range range;
+ 
+ 	if (!vma || !vma->vm_file ||
+ 	    !range_in_vma(vma, haddr, haddr + HPAGE_PMD_SIZE))
+@@ -1456,6 +1458,14 @@ void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr)
+ 	if (!hugepage_vma_check(vma, vma->vm_flags | VM_HUGEPAGE))
+ 		return;
+ 
++	/*
++	 * Symmetry with retract_page_tables(): Exclude MAP_PRIVATE mappings
++	 * that got written to. Without this, we'd have to also lock the
++	 * anon_vma if one exists.
++	 */
++	if (vma->anon_vma)
++		return;
++
+ 	hpage = find_lock_page(vma->vm_file->f_mapping,
+ 			       linear_page_index(vma, haddr));
+ 	if (!hpage)
+@@ -1468,6 +1478,19 @@ void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr)
+ 	if (!pmd)
+ 		goto drop_hpage;
+ 
++	/*
++	 * We need to lock the mapping so that from here on, only GUP-fast and
++	 * hardware page walks can access the parts of the page tables that
++	 * we're operating on.
++	 */
++	i_mmap_lock_write(vma->vm_file->f_mapping);
++
++	/*
++	 * This spinlock should be unnecessary: Nobody else should be accessing
++	 * the page tables under spinlock protection here, only
++	 * lockless_pages_from_mm() and the hardware page walker can access page
++	 * tables while all the high-level locks are held in write mode.
++	 */
+ 	start_pte = pte_offset_map_lock(mm, pmd, haddr, &ptl);
+ 
+ 	/* step 1: check all mapped PTEs are to the right huge page */
+@@ -1514,12 +1537,17 @@ void collapse_pte_mapped_thp(struct mm_struct *mm, unsigned long addr)
+ 	}
+ 
+ 	/* step 4: collapse pmd */
+-	ptl = pmd_lock(vma->vm_mm, pmd);
++	mmu_notifier_range_init(&range, MMU_NOTIFY_CLEAR, 0, NULL, mm, haddr,
++				haddr + HPAGE_PMD_SIZE);
++	mmu_notifier_invalidate_range_start(&range);
+ 	_pmd = pmdp_collapse_flush(vma, haddr, pmd);
+-	spin_unlock(ptl);
+ 	mm_dec_nr_ptes(mm);
++	tlb_remove_table_sync_one();
++	mmu_notifier_invalidate_range_end(&range);
+ 	pte_free(mm, pmd_pgtable(_pmd));
+ 
++	i_mmap_unlock_write(vma->vm_file->f_mapping);
++
+ drop_hpage:
+ 	unlock_page(hpage);
+ 	put_page(hpage);
+@@ -1527,6 +1555,7 @@ drop_hpage:
+ 
+ abort:
+ 	pte_unmap_unlock(start_pte, ptl);
++	i_mmap_unlock_write(vma->vm_file->f_mapping);
+ 	goto drop_hpage;
+ }
+ 
+@@ -1575,7 +1604,8 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
+ 		 * An alternative would be drop the check, but check that page
+ 		 * table is clear before calling pmdp_collapse_flush() under
+ 		 * ptl. It has higher chance to recover THP for the VMA, but
+-		 * has higher cost too.
++		 * has higher cost too. It would also probably require locking
++		 * the anon_vma.
+ 		 */
+ 		if (vma->anon_vma)
+ 			continue;
+@@ -1597,12 +1627,19 @@ static void retract_page_tables(struct address_space *mapping, pgoff_t pgoff)
+ 		 */
+ 		if (mmap_write_trylock(mm)) {
+ 			if (!khugepaged_test_exit(mm)) {
+-				spinlock_t *ptl = pmd_lock(mm, pmd);
++				struct mmu_notifier_range range;
++
++				mmu_notifier_range_init(&range,
++							MMU_NOTIFY_CLEAR, 0,
++							NULL, mm, addr,
++							addr + HPAGE_PMD_SIZE);
++				mmu_notifier_invalidate_range_start(&range);
+ 				/* assume page table is clear */
+ 				_pmd = pmdp_collapse_flush(vma, addr, pmd);
+-				spin_unlock(ptl);
+ 				mm_dec_nr_ptes(mm);
++				tlb_remove_table_sync_one();
+ 				pte_free(mm, pmd_pgtable(_pmd));
++				mmu_notifier_invalidate_range_end(&range);
+ 			}
+ 			mmap_write_unlock(mm);
+ 		} else {
+diff --git a/mm/memcontrol.c b/mm/memcontrol.c
+index 971546bb99e04..3d3364cd4ff19 100644
+--- a/mm/memcontrol.c
++++ b/mm/memcontrol.c
+@@ -4789,6 +4789,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
+ 	unsigned int efd, cfd;
+ 	struct fd efile;
+ 	struct fd cfile;
++	struct dentry *cdentry;
+ 	const char *name;
+ 	char *endp;
+ 	int ret;
+@@ -4839,6 +4840,16 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
+ 	if (ret < 0)
+ 		goto out_put_cfile;
+ 
++	/*
++	 * The control file must be a regular cgroup1 file. As a regular cgroup
++	 * file can't be renamed, it's safe to access its name afterwards.
++	 */
++	cdentry = cfile.file->f_path.dentry;
++	if (cdentry->d_sb->s_type != &cgroup_fs_type || !d_is_reg(cdentry)) {
++		ret = -EINVAL;
++		goto out_put_cfile;
++	}
++
+ 	/*
+ 	 * Determine the event callbacks and set them in @event.  This used
+ 	 * to be done via struct cftype but cgroup core no longer knows
+@@ -4847,7 +4858,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
+ 	 *
+ 	 * DO NOT ADD NEW FILES.
+ 	 */
+-	name = cfile.file->f_path.dentry->d_name.name;
++	name = cdentry->d_name.name;
+ 
+ 	if (!strcmp(name, "memory.usage_in_bytes")) {
+ 		event->register_event = mem_cgroup_usage_register_event;
+@@ -4871,7 +4882,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
+ 	 * automatically removed on cgroup destruction but the removal is
+ 	 * asynchronous, so take an extra ref on @css.
+ 	 */
+-	cfile_css = css_tryget_online_from_dir(cfile.file->f_path.dentry->d_parent,
++	cfile_css = css_tryget_online_from_dir(cdentry->d_parent,
+ 					       &memory_cgrp_subsys);
+ 	ret = -EINVAL;
+ 	if (IS_ERR(cfile_css))
+diff --git a/mm/mmu_gather.c b/mm/mmu_gather.c
+index 1b9837419bf9c..8be26c7ddb47f 100644
+--- a/mm/mmu_gather.c
++++ b/mm/mmu_gather.c
+@@ -139,7 +139,7 @@ static void tlb_remove_table_smp_sync(void *arg)
+ 	/* Simply deliver the interrupt */
+ }
+ 
+-static void tlb_remove_table_sync_one(void)
++void tlb_remove_table_sync_one(void)
+ {
+ 	/*
+ 	 * This isn't an RCU grace period and hence the page-tables cannot be
+@@ -163,8 +163,6 @@ static void tlb_remove_table_free(struct mmu_table_batch *batch)
+ 
+ #else /* !CONFIG_MMU_GATHER_RCU_TABLE_FREE */
+ 
+-static void tlb_remove_table_sync_one(void) { }
+-
+ static void tlb_remove_table_free(struct mmu_table_batch *batch)
+ {
+ 	__tlb_remove_table_free(batch);
+diff --git a/net/9p/trans_fd.c b/net/9p/trans_fd.c
+index e1c2c9242ce22..f359cfdc1858f 100644
+--- a/net/9p/trans_fd.c
++++ b/net/9p/trans_fd.c
+@@ -122,7 +122,7 @@ struct p9_conn {
+ 	struct list_head unsent_req_list;
+ 	struct p9_req_t *rreq;
+ 	struct p9_req_t *wreq;
+-	char tmp_buf[7];
++	char tmp_buf[P9_HDRSZ];
+ 	struct p9_fcall rc;
+ 	int wpos;
+ 	int wsize;
+@@ -295,7 +295,7 @@ static void p9_read_work(struct work_struct *work)
+ 	if (!m->rc.sdata) {
+ 		m->rc.sdata = m->tmp_buf;
+ 		m->rc.offset = 0;
+-		m->rc.capacity = 7; /* start by reading header */
++		m->rc.capacity = P9_HDRSZ; /* start by reading header */
+ 	}
+ 
+ 	clear_bit(Rpending, &m->wsched);
+@@ -318,7 +318,7 @@ static void p9_read_work(struct work_struct *work)
+ 		p9_debug(P9_DEBUG_TRANS, "got new header\n");
+ 
+ 		/* Header size */
+-		m->rc.size = 7;
++		m->rc.size = P9_HDRSZ;
+ 		err = p9_parse_header(&m->rc, &m->rc.size, NULL, NULL, 0);
+ 		if (err) {
+ 			p9_debug(P9_DEBUG_ERROR,
+diff --git a/net/9p/trans_xen.c b/net/9p/trans_xen.c
+index 427f6caefa29f..4255f2a3bea48 100644
+--- a/net/9p/trans_xen.c
++++ b/net/9p/trans_xen.c
+@@ -231,6 +231,14 @@ static void p9_xen_response(struct work_struct *work)
+ 			continue;
+ 		}
+ 
++		if (h.size > req->rc.capacity) {
++			dev_warn(&priv->dev->dev,
++				 "requested packet size too big: %d for tag %d with capacity %zd\n",
++				 h.size, h.tag, req->rc.capacity);
++			req->status = REQ_STATUS_ERROR;
++			goto recv_error;
++		}
++
+ 		memcpy(&req->rc, &h, sizeof(h));
+ 		req->rc.offset = 0;
+ 
+@@ -240,6 +248,7 @@ static void p9_xen_response(struct work_struct *work)
+ 				     masked_prod, &masked_cons,
+ 				     XEN_9PFS_RING_SIZE(ring));
+ 
++recv_error:
+ 		virt_mb();
+ 		cons += h.size;
+ 		ring->intf->in_cons = cons;
+diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
+index fd164a248569c..580b0940f067a 100644
+--- a/net/bluetooth/6lowpan.c
++++ b/net/bluetooth/6lowpan.c
+@@ -971,6 +971,7 @@ static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
+ 	hci_dev_lock(hdev);
+ 	hcon = hci_conn_hash_lookup_le(hdev, addr, *addr_type);
+ 	hci_dev_unlock(hdev);
++	hci_dev_put(hdev);
+ 
+ 	if (!hcon)
+ 		return -ENOENT;
+diff --git a/net/bluetooth/af_bluetooth.c b/net/bluetooth/af_bluetooth.c
+index 1661979b6a6e8..ce744b14d1a98 100644
+--- a/net/bluetooth/af_bluetooth.c
++++ b/net/bluetooth/af_bluetooth.c
+@@ -736,7 +736,7 @@ static int __init bt_init(void)
+ 
+ 	err = bt_sysfs_init();
+ 	if (err < 0)
+-		return err;
++		goto cleanup_led;
+ 
+ 	err = sock_register(&bt_sock_family_ops);
+ 	if (err)
+@@ -772,6 +772,8 @@ unregister_socket:
+ 	sock_unregister(PF_BLUETOOTH);
+ cleanup_sysfs:
+ 	bt_sysfs_cleanup();
++cleanup_led:
++	bt_leds_cleanup();
+ 	return err;
+ }
+ 
+diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
+index 396696241d17f..bb84ff5fb98a2 100644
+--- a/net/bluetooth/hci_core.c
++++ b/net/bluetooth/hci_core.c
+@@ -3985,7 +3985,8 @@ int hci_register_dev(struct hci_dev *hdev)
+ 	hci_sock_dev_event(hdev, HCI_DEV_REG);
+ 	hci_dev_hold(hdev);
+ 
+-	if (!test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks)) {
++	if (!hdev->suspend_notifier.notifier_call &&
++	    !test_bit(HCI_QUIRK_NO_SUSPEND_NOTIFIER, &hdev->quirks)) {
+ 		hdev->suspend_notifier.notifier_call = hci_suspend_notifier;
+ 		error = register_pm_notifier(&hdev->suspend_notifier);
+ 		if (error)
+diff --git a/net/can/af_can.c b/net/can/af_can.c
+index 4ddefa6a3e055..20d2dcb7c97ae 100644
+--- a/net/can/af_can.c
++++ b/net/can/af_can.c
+@@ -680,7 +680,7 @@ static int can_rcv(struct sk_buff *skb, struct net_device *dev,
+ {
+ 	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+ 
+-	if (unlikely(dev->type != ARPHRD_CAN || skb->len != CAN_MTU)) {
++	if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || skb->len != CAN_MTU)) {
+ 		pr_warn_once("PF_CAN: dropped non conform CAN skbuff: dev type %d, len %d\n",
+ 			     dev->type, skb->len);
+ 		goto free_skb;
+@@ -706,7 +706,7 @@ static int canfd_rcv(struct sk_buff *skb, struct net_device *dev,
+ {
+ 	struct canfd_frame *cfd = (struct canfd_frame *)skb->data;
+ 
+-	if (unlikely(dev->type != ARPHRD_CAN || skb->len != CANFD_MTU)) {
++	if (unlikely(dev->type != ARPHRD_CAN || !can_get_ml_priv(dev) || skb->len != CANFD_MTU)) {
+ 		pr_warn_once("PF_CAN: dropped non conform CAN FD skbuff: dev type %d, len %d\n",
+ 			     dev->type, skb->len);
+ 		goto free_skb;
+diff --git a/net/dsa/tag_hellcreek.c b/net/dsa/tag_hellcreek.c
+index 846588c0070a5..53a206d116850 100644
+--- a/net/dsa/tag_hellcreek.c
++++ b/net/dsa/tag_hellcreek.c
+@@ -49,7 +49,8 @@ static struct sk_buff *hellcreek_rcv(struct sk_buff *skb,
+ 		return NULL;
+ 	}
+ 
+-	pskb_trim_rcsum(skb, skb->len - HELLCREEK_TAG_LEN);
++	if (pskb_trim_rcsum(skb, skb->len - HELLCREEK_TAG_LEN))
++		return NULL;
+ 
+ 	dsa_default_offload_fwd_mark(skb);
+ 
+diff --git a/net/dsa/tag_ksz.c b/net/dsa/tag_ksz.c
+index fa1d60d13ad90..6795dd0174996 100644
+--- a/net/dsa/tag_ksz.c
++++ b/net/dsa/tag_ksz.c
+@@ -22,7 +22,8 @@ static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
+ 	if (!skb->dev)
+ 		return NULL;
+ 
+-	pskb_trim_rcsum(skb, skb->len - len);
++	if (pskb_trim_rcsum(skb, skb->len - len))
++		return NULL;
+ 
+ 	dsa_default_offload_fwd_mark(skb);
+ 
+diff --git a/net/dsa/tag_sja1105.c b/net/dsa/tag_sja1105.c
+index 2edede9ddac93..d43feadd5fa6b 100644
+--- a/net/dsa/tag_sja1105.c
++++ b/net/dsa/tag_sja1105.c
+@@ -644,7 +644,8 @@ static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
+ 		 * padding and trailer we need to account for the fact that
+ 		 * skb->data points to skb_mac_header(skb) + ETH_HLEN.
+ 		 */
+-		pskb_trim_rcsum(skb, start_of_padding - ETH_HLEN);
++		if (pskb_trim_rcsum(skb, start_of_padding - ETH_HLEN))
++			return NULL;
+ 	/* Trap-to-host frame, no timestamp trailer */
+ 	} else {
+ 		*source_port = SJA1110_RX_HEADER_SRC_PORT(rx_header);
+diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c
+index 1452bb72b7d9c..75c88d4863276 100644
+--- a/net/ipv4/fib_frontend.c
++++ b/net/ipv4/fib_frontend.c
+@@ -830,6 +830,9 @@ static int rtm_to_fib_config(struct net *net, struct sk_buff *skb,
+ 		return -EINVAL;
+ 	}
+ 
++	if (!cfg->fc_table)
++		cfg->fc_table = RT_TABLE_MAIN;
++
+ 	return 0;
+ errout:
+ 	return err;
+diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
+index af64ae689b13d..250af6e5a8922 100644
+--- a/net/ipv4/fib_semantics.c
++++ b/net/ipv4/fib_semantics.c
+@@ -421,6 +421,7 @@ static struct fib_info *fib_find_info(struct fib_info *nfi)
+ 		    nfi->fib_prefsrc == fi->fib_prefsrc &&
+ 		    nfi->fib_priority == fi->fib_priority &&
+ 		    nfi->fib_type == fi->fib_type &&
++		    nfi->fib_tb_id == fi->fib_tb_id &&
+ 		    memcmp(nfi->fib_metrics, fi->fib_metrics,
+ 			   sizeof(u32) * RTAX_MAX) == 0 &&
+ 		    !((nfi->fib_flags ^ fi->fib_flags) & ~RTNH_COMPARE_MASK) &&
+diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
+index fc74a3e3b3e12..454c4357a2979 100644
+--- a/net/ipv4/ip_gre.c
++++ b/net/ipv4/ip_gre.c
+@@ -1498,24 +1498,6 @@ static int ipgre_fill_info(struct sk_buff *skb, const struct net_device *dev)
+ 	struct ip_tunnel_parm *p = &t->parms;
+ 	__be16 o_flags = p->o_flags;
+ 
+-	if (t->erspan_ver <= 2) {
+-		if (t->erspan_ver != 0 && !t->collect_md)
+-			o_flags |= TUNNEL_KEY;
+-
+-		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver))
+-			goto nla_put_failure;
+-
+-		if (t->erspan_ver == 1) {
+-			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
+-				goto nla_put_failure;
+-		} else if (t->erspan_ver == 2) {
+-			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir))
+-				goto nla_put_failure;
+-			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))
+-				goto nla_put_failure;
+-		}
+-	}
+-
+ 	if (nla_put_u32(skb, IFLA_GRE_LINK, p->link) ||
+ 	    nla_put_be16(skb, IFLA_GRE_IFLAGS,
+ 			 gre_tnl_flags_to_gre_flags(p->i_flags)) ||
+@@ -1556,6 +1538,34 @@ nla_put_failure:
+ 	return -EMSGSIZE;
+ }
+ 
++static int erspan_fill_info(struct sk_buff *skb, const struct net_device *dev)
++{
++	struct ip_tunnel *t = netdev_priv(dev);
++
++	if (t->erspan_ver <= 2) {
++		if (t->erspan_ver != 0 && !t->collect_md)
++			t->parms.o_flags |= TUNNEL_KEY;
++
++		if (nla_put_u8(skb, IFLA_GRE_ERSPAN_VER, t->erspan_ver))
++			goto nla_put_failure;
++
++		if (t->erspan_ver == 1) {
++			if (nla_put_u32(skb, IFLA_GRE_ERSPAN_INDEX, t->index))
++				goto nla_put_failure;
++		} else if (t->erspan_ver == 2) {
++			if (nla_put_u8(skb, IFLA_GRE_ERSPAN_DIR, t->dir))
++				goto nla_put_failure;
++			if (nla_put_u16(skb, IFLA_GRE_ERSPAN_HWID, t->hwid))
++				goto nla_put_failure;
++		}
++	}
++
++	return ipgre_fill_info(skb, dev);
++
++nla_put_failure:
++	return -EMSGSIZE;
++}
++
+ static void erspan_setup(struct net_device *dev)
+ {
+ 	struct ip_tunnel *t = netdev_priv(dev);
+@@ -1634,7 +1644,7 @@ static struct rtnl_link_ops erspan_link_ops __read_mostly = {
+ 	.changelink	= erspan_changelink,
+ 	.dellink	= ip_tunnel_dellink,
+ 	.get_size	= ipgre_get_size,
+-	.fill_info	= ipgre_fill_info,
++	.fill_info	= erspan_fill_info,
+ 	.get_link_net	= ip_tunnel_get_link_net,
+ };
+ 
+diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
+index 7951ade74d142..675a80dd78ba6 100644
+--- a/net/ipv6/ip6_output.c
++++ b/net/ipv6/ip6_output.c
+@@ -897,6 +897,9 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
+ 		if (err < 0)
+ 			goto fail;
+ 
++		/* We prevent @rt from being freed. */
++		rcu_read_lock();
++
+ 		for (;;) {
+ 			/* Prepare header of the next frame,
+ 			 * before previous one went down. */
+@@ -920,6 +923,7 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
+ 		if (err == 0) {
+ 			IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
+ 				      IPSTATS_MIB_FRAGOKS);
++			rcu_read_unlock();
+ 			return 0;
+ 		}
+ 
+@@ -927,6 +931,7 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
+ 
+ 		IP6_INC_STATS(net, ip6_dst_idev(&rt->dst),
+ 			      IPSTATS_MIB_FRAGFAILS);
++		rcu_read_unlock();
+ 		return err;
+ 
+ slow_path_clean:
+diff --git a/net/mac802154/iface.c b/net/mac802154/iface.c
+index 323d3d2d986f8..3e510664fc891 100644
+--- a/net/mac802154/iface.c
++++ b/net/mac802154/iface.c
+@@ -661,6 +661,7 @@ ieee802154_if_add(struct ieee802154_local *local, const char *name,
+ 	sdata->dev = ndev;
+ 	sdata->wpan_dev.wpan_phy = local->hw.phy;
+ 	sdata->local = local;
++	INIT_LIST_HEAD(&sdata->wpan_dev.list);
+ 
+ 	/* setup type-dependent data */
+ 	ret = ieee802154_setup_sdata(sdata, type);
+diff --git a/net/netfilter/nf_conntrack_netlink.c b/net/netfilter/nf_conntrack_netlink.c
+index 1727a4c4764f0..2cc6092b4f865 100644
+--- a/net/netfilter/nf_conntrack_netlink.c
++++ b/net/netfilter/nf_conntrack_netlink.c
+@@ -322,8 +322,13 @@ nla_put_failure:
+ }
+ 
+ #ifdef CONFIG_NF_CONNTRACK_MARK
+-static int ctnetlink_dump_mark(struct sk_buff *skb, u32 mark)
++static int ctnetlink_dump_mark(struct sk_buff *skb, const struct nf_conn *ct)
+ {
++	u32 mark = READ_ONCE(ct->mark);
++
++	if (!mark)
++		return 0;
++
+ 	if (nla_put_be32(skb, CTA_MARK, htonl(mark)))
+ 		goto nla_put_failure;
+ 	return 0;
+@@ -537,7 +542,7 @@ static int ctnetlink_dump_extinfo(struct sk_buff *skb,
+ static int ctnetlink_dump_info(struct sk_buff *skb, struct nf_conn *ct)
+ {
+ 	if (ctnetlink_dump_status(skb, ct) < 0 ||
+-	    ctnetlink_dump_mark(skb, READ_ONCE(ct->mark)) < 0 ||
++	    ctnetlink_dump_mark(skb, ct) < 0 ||
+ 	    ctnetlink_dump_secctx(skb, ct) < 0 ||
+ 	    ctnetlink_dump_id(skb, ct) < 0 ||
+ 	    ctnetlink_dump_use(skb, ct) < 0 ||
+@@ -716,7 +721,6 @@ ctnetlink_conntrack_event(unsigned int events, const struct nf_ct_event *item)
+ 	struct sk_buff *skb;
+ 	unsigned int type;
+ 	unsigned int flags = 0, group;
+-	u32 mark;
+ 	int err;
+ 
+ 	if (events & (1 << IPCT_DESTROY)) {
+@@ -821,9 +825,8 @@ ctnetlink_conntrack_event(unsigned int events, const struct nf_ct_event *item)
+ 	}
+ 
+ #ifdef CONFIG_NF_CONNTRACK_MARK
+-	mark = READ_ONCE(ct->mark);
+-	if ((events & (1 << IPCT_MARK) || mark) &&
+-	    ctnetlink_dump_mark(skb, mark) < 0)
++	if (events & (1 << IPCT_MARK) &&
++	    ctnetlink_dump_mark(skb, ct) < 0)
+ 		goto nla_put_failure;
+ #endif
+ 	nlmsg_end(skb, nlh);
+@@ -2692,7 +2695,6 @@ static int __ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct)
+ {
+ 	const struct nf_conntrack_zone *zone;
+ 	struct nlattr *nest_parms;
+-	u32 mark;
+ 
+ 	zone = nf_ct_zone(ct);
+ 
+@@ -2754,8 +2756,7 @@ static int __ctnetlink_glue_build(struct sk_buff *skb, struct nf_conn *ct)
+ 		goto nla_put_failure;
+ 
+ #ifdef CONFIG_NF_CONNTRACK_MARK
+-	mark = READ_ONCE(ct->mark);
+-	if (mark && ctnetlink_dump_mark(skb, mark) < 0)
++	if (ctnetlink_dump_mark(skb, ct) < 0)
+ 		goto nla_put_failure;
+ #endif
+ 	if (ctnetlink_dump_labels(skb, ct) < 0)
+diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c
+index 4f9299b9dcddc..06d46d1826347 100644
+--- a/net/netfilter/nft_set_pipapo.c
++++ b/net/netfilter/nft_set_pipapo.c
+@@ -1162,6 +1162,7 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
+ 	struct nft_pipapo_match *m = priv->clone;
+ 	u8 genmask = nft_genmask_next(net);
+ 	struct nft_pipapo_field *f;
++	const u8 *start_p, *end_p;
+ 	int i, bsize_max, err = 0;
+ 
+ 	if (nft_set_ext_exists(ext, NFT_SET_EXT_KEY_END))
+@@ -1202,9 +1203,9 @@ static int nft_pipapo_insert(const struct net *net, const struct nft_set *set,
+ 	}
+ 
+ 	/* Validate */
++	start_p = start;
++	end_p = end;
+ 	nft_pipapo_for_each_field(f, i, m) {
+-		const u8 *start_p = start, *end_p = end;
+-
+ 		if (f->rules >= (unsigned long)NFT_PIPAPO_RULE0_MAX)
+ 			return -ENOSPC;
+ 
+diff --git a/net/nfc/nci/ntf.c b/net/nfc/nci/ntf.c
+index c5eacaac41aea..8f48b10619448 100644
+--- a/net/nfc/nci/ntf.c
++++ b/net/nfc/nci/ntf.c
+@@ -240,6 +240,8 @@ static int nci_add_new_protocol(struct nci_dev *ndev,
+ 		target->sens_res = nfca_poll->sens_res;
+ 		target->sel_res = nfca_poll->sel_res;
+ 		target->nfcid1_len = nfca_poll->nfcid1_len;
++		if (target->nfcid1_len > ARRAY_SIZE(target->nfcid1))
++			return -EPROTO;
+ 		if (target->nfcid1_len > 0) {
+ 			memcpy(target->nfcid1, nfca_poll->nfcid1,
+ 			       target->nfcid1_len);
+@@ -248,6 +250,8 @@ static int nci_add_new_protocol(struct nci_dev *ndev,
+ 		nfcb_poll = (struct rf_tech_specific_params_nfcb_poll *)params;
+ 
+ 		target->sensb_res_len = nfcb_poll->sensb_res_len;
++		if (target->sensb_res_len > ARRAY_SIZE(target->sensb_res))
++			return -EPROTO;
+ 		if (target->sensb_res_len > 0) {
+ 			memcpy(target->sensb_res, nfcb_poll->sensb_res,
+ 			       target->sensb_res_len);
+@@ -256,6 +260,8 @@ static int nci_add_new_protocol(struct nci_dev *ndev,
+ 		nfcf_poll = (struct rf_tech_specific_params_nfcf_poll *)params;
+ 
+ 		target->sensf_res_len = nfcf_poll->sensf_res_len;
++		if (target->sensf_res_len > ARRAY_SIZE(target->sensf_res))
++			return -EPROTO;
+ 		if (target->sensf_res_len > 0) {
+ 			memcpy(target->sensf_res, nfcf_poll->sensf_res,
+ 			       target->sensf_res_len);
+diff --git a/net/tipc/link.c b/net/tipc/link.c
+index 115a4a7950f50..8fdd3b23bd123 100644
+--- a/net/tipc/link.c
++++ b/net/tipc/link.c
+@@ -2223,7 +2223,9 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
+ 	if (tipc_own_addr(l->net) > msg_prevnode(hdr))
+ 		l->net_plane = msg_net_plane(hdr);
+ 
+-	skb_linearize(skb);
++	if (skb_linearize(skb))
++		goto exit;
++
+ 	hdr = buf_msg(skb);
+ 	data = msg_data(hdr);
+ 
+diff --git a/net/tipc/node.c b/net/tipc/node.c
+index b48d97cbbe29c..49ddc484c4fe7 100644
+--- a/net/tipc/node.c
++++ b/net/tipc/node.c
+@@ -1689,6 +1689,7 @@ int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
+ 	struct tipc_node *n;
+ 	struct sk_buff_head xmitq;
+ 	bool node_up = false;
++	struct net *peer_net;
+ 	int bearer_id;
+ 	int rc;
+ 
+@@ -1705,18 +1706,23 @@ int tipc_node_xmit(struct net *net, struct sk_buff_head *list,
+ 		return -EHOSTUNREACH;
+ 	}
+ 
++	rcu_read_lock();
+ 	tipc_node_read_lock(n);
+ 	node_up = node_is_up(n);
+-	if (node_up && n->peer_net && check_net(n->peer_net)) {
++	peer_net = n->peer_net;
++	tipc_node_read_unlock(n);
++	if (node_up && peer_net && check_net(peer_net)) {
+ 		/* xmit inner linux container */
+-		tipc_lxc_xmit(n->peer_net, list);
++		tipc_lxc_xmit(peer_net, list);
+ 		if (likely(skb_queue_empty(list))) {
+-			tipc_node_read_unlock(n);
++			rcu_read_unlock();
+ 			tipc_node_put(n);
+ 			return 0;
+ 		}
+ 	}
++	rcu_read_unlock();
+ 
++	tipc_node_read_lock(n);
+ 	bearer_id = n->active_links[selector & 1];
+ 	if (unlikely(bearer_id == INVALID_BEARER_ID)) {
+ 		tipc_node_read_unlock(n);
+diff --git a/net/unix/diag.c b/net/unix/diag.c
+index 7e7d7f45685af..e534e327a6a5a 100644
+--- a/net/unix/diag.c
++++ b/net/unix/diag.c
+@@ -113,14 +113,16 @@ static int sk_diag_show_rqlen(struct sock *sk, struct sk_buff *nlskb)
+ 	return nla_put(nlskb, UNIX_DIAG_RQLEN, sizeof(rql), &rql);
+ }
+ 
+-static int sk_diag_dump_uid(struct sock *sk, struct sk_buff *nlskb)
++static int sk_diag_dump_uid(struct sock *sk, struct sk_buff *nlskb,
++			    struct user_namespace *user_ns)
+ {
+-	uid_t uid = from_kuid_munged(sk_user_ns(nlskb->sk), sock_i_uid(sk));
++	uid_t uid = from_kuid_munged(user_ns, sock_i_uid(sk));
+ 	return nla_put(nlskb, UNIX_DIAG_UID, sizeof(uid_t), &uid);
+ }
+ 
+ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req,
+-		u32 portid, u32 seq, u32 flags, int sk_ino)
++			struct user_namespace *user_ns,
++			u32 portid, u32 seq, u32 flags, int sk_ino)
+ {
+ 	struct nlmsghdr *nlh;
+ 	struct unix_diag_msg *rep;
+@@ -166,7 +168,7 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, struct unix_diag_r
+ 		goto out_nlmsg_trim;
+ 
+ 	if ((req->udiag_show & UDIAG_SHOW_UID) &&
+-	    sk_diag_dump_uid(sk, skb))
++	    sk_diag_dump_uid(sk, skb, user_ns))
+ 		goto out_nlmsg_trim;
+ 
+ 	nlmsg_end(skb, nlh);
+@@ -178,7 +180,8 @@ out_nlmsg_trim:
+ }
+ 
+ static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_req *req,
+-		u32 portid, u32 seq, u32 flags)
++			struct user_namespace *user_ns,
++			u32 portid, u32 seq, u32 flags)
+ {
+ 	int sk_ino;
+ 
+@@ -189,7 +192,7 @@ static int sk_diag_dump(struct sock *sk, struct sk_buff *skb, struct unix_diag_r
+ 	if (!sk_ino)
+ 		return 0;
+ 
+-	return sk_diag_fill(sk, skb, req, portid, seq, flags, sk_ino);
++	return sk_diag_fill(sk, skb, req, user_ns, portid, seq, flags, sk_ino);
+ }
+ 
+ static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
+@@ -217,7 +220,7 @@ static int unix_diag_dump(struct sk_buff *skb, struct netlink_callback *cb)
+ 				goto next;
+ 			if (!(req->udiag_states & (1 << sk->sk_state)))
+ 				goto next;
+-			if (sk_diag_dump(sk, skb, req,
++			if (sk_diag_dump(sk, skb, req, sk_user_ns(skb->sk),
+ 					 NETLINK_CB(cb->skb).portid,
+ 					 cb->nlh->nlmsg_seq,
+ 					 NLM_F_MULTI) < 0)
+@@ -285,7 +288,8 @@ again:
+ 	if (!rep)
+ 		goto out;
+ 
+-	err = sk_diag_fill(sk, rep, req, NETLINK_CB(in_skb).portid,
++	err = sk_diag_fill(sk, rep, req, sk_user_ns(NETLINK_CB(in_skb).sk),
++			   NETLINK_CB(in_skb).portid,
+ 			   nlh->nlmsg_seq, 0, req->udiag_ino);
+ 	if (err < 0) {
+ 		nlmsg_free(rep);
+diff --git a/sound/core/seq/seq_memory.c b/sound/core/seq/seq_memory.c
+index b7aee23fc3876..47ef6bc30c0ee 100644
+--- a/sound/core/seq/seq_memory.c
++++ b/sound/core/seq/seq_memory.c
+@@ -113,15 +113,19 @@ EXPORT_SYMBOL(snd_seq_dump_var_event);
+  * expand the variable length event to linear buffer space.
+  */
+ 
+-static int seq_copy_in_kernel(char **bufptr, const void *src, int size)
++static int seq_copy_in_kernel(void *ptr, void *src, int size)
+ {
++	char **bufptr = ptr;
++
+ 	memcpy(*bufptr, src, size);
+ 	*bufptr += size;
+ 	return 0;
+ }
+ 
+-static int seq_copy_in_user(char __user **bufptr, const void *src, int size)
++static int seq_copy_in_user(void *ptr, void *src, int size)
+ {
++	char __user **bufptr = ptr;
++
+ 	if (copy_to_user(*bufptr, src, size))
+ 		return -EFAULT;
+ 	*bufptr += size;
+@@ -151,8 +155,7 @@ int snd_seq_expand_var_event(const struct snd_seq_event *event, int count, char
+ 		return newlen;
+ 	}
+ 	err = snd_seq_dump_var_event(event,
+-				     in_kernel ? (snd_seq_dump_func_t)seq_copy_in_kernel :
+-				     (snd_seq_dump_func_t)seq_copy_in_user,
++				     in_kernel ? seq_copy_in_kernel : seq_copy_in_user,
+ 				     &buf);
+ 	return err < 0 ? err : newlen;
+ }
+diff --git a/sound/soc/codecs/rt711-sdca-sdw.c b/sound/soc/codecs/rt711-sdca-sdw.c
+index a085b2f530aa1..31e77d462ef34 100644
+--- a/sound/soc/codecs/rt711-sdca-sdw.c
++++ b/sound/soc/codecs/rt711-sdca-sdw.c
+@@ -230,7 +230,7 @@ static int rt711_sdca_read_prop(struct sdw_slave *slave)
+ 	}
+ 
+ 	/* set the timeout values */
+-	prop->clk_stop_timeout = 20;
++	prop->clk_stop_timeout = 700;
+ 
+ 	/* wake-up event */
+ 	prop->wake_capable = 1;
+diff --git a/sound/soc/codecs/wm8962.c b/sound/soc/codecs/wm8962.c
+index 09a73b8549641..779f7097d336c 100644
+--- a/sound/soc/codecs/wm8962.c
++++ b/sound/soc/codecs/wm8962.c
+@@ -2490,6 +2490,14 @@ static void wm8962_configure_bclk(struct snd_soc_component *component)
+ 		snd_soc_component_update_bits(component, WM8962_CLOCKING2,
+ 				WM8962_SYSCLK_ENA_MASK, WM8962_SYSCLK_ENA);
+ 
++	/* DSPCLK_DIV field in WM8962_CLOCKING1 register is used to generate
++	 * correct frequency of LRCLK and BCLK. Sometimes the read-only value
++	 * can't be updated timely after enabling SYSCLK. This results in wrong
++	 * calculation values. Delay is introduced here to wait for newest
++	 * value from register. The time of the delay should be at least
++	 * 500~1000us according to test.
++	 */
++	usleep_range(500, 1000);
+ 	dspclk = snd_soc_component_read(component, WM8962_CLOCKING1);
+ 
+ 	if (snd_soc_component_get_bias_level(component) != SND_SOC_BIAS_ON)
+diff --git a/sound/soc/soc-pcm.c b/sound/soc/soc-pcm.c
+index f6dc71e8ea879..3b673477f6215 100644
+--- a/sound/soc/soc-pcm.c
++++ b/sound/soc/soc-pcm.c
+@@ -1166,6 +1166,8 @@ static void dpcm_be_reparent(struct snd_soc_pcm_runtime *fe,
+ 		return;
+ 
+ 	be_substream = snd_soc_dpcm_get_substream(be, stream);
++	if (!be_substream)
++		return;
+ 
+ 	for_each_dpcm_fe(be, stream, dpcm) {
+ 		if (dpcm->fe == fe)
+diff --git a/tools/testing/selftests/net/fcnal-test.sh b/tools/testing/selftests/net/fcnal-test.sh
+index 91f54112167f1..364c82b797c19 100755
+--- a/tools/testing/selftests/net/fcnal-test.sh
++++ b/tools/testing/selftests/net/fcnal-test.sh
+@@ -4072,10 +4072,13 @@ elif [ "$TESTS" = "ipv6" ]; then
+ 	TESTS="$TESTS_IPV6"
+ fi
+ 
+-which nettest >/dev/null
+-if [ $? -ne 0 ]; then
+-	echo "'nettest' command not found; skipping tests"
+-	exit $ksft_skip
++# nettest can be run from PATH or from same directory as this selftest
++if ! which nettest >/dev/null; then
++	PATH=$PWD:$PATH
++	if ! which nettest >/dev/null; then
++		echo "'nettest' command not found; skipping tests"
++		exit $ksft_skip
++	fi
+ fi
+ 
+ declare -i nfail=0
+diff --git a/tools/testing/selftests/net/fib_tests.sh b/tools/testing/selftests/net/fib_tests.sh
+index 996af1ae3d3dd..7df066bf74b87 100755
+--- a/tools/testing/selftests/net/fib_tests.sh
++++ b/tools/testing/selftests/net/fib_tests.sh
+@@ -1622,13 +1622,21 @@ ipv4_del_addr_test()
+ 
+ 	$IP addr add dev dummy1 172.16.104.1/24
+ 	$IP addr add dev dummy1 172.16.104.11/24
++	$IP addr add dev dummy1 172.16.104.12/24
++	$IP addr add dev dummy1 172.16.104.13/24
+ 	$IP addr add dev dummy2 172.16.104.1/24
+ 	$IP addr add dev dummy2 172.16.104.11/24
++	$IP addr add dev dummy2 172.16.104.12/24
+ 	$IP route add 172.16.105.0/24 via 172.16.104.2 src 172.16.104.11
++	$IP route add 172.16.106.0/24 dev lo src 172.16.104.12
++	$IP route add table 0 172.16.107.0/24 via 172.16.104.2 src 172.16.104.13
+ 	$IP route add vrf red 172.16.105.0/24 via 172.16.104.2 src 172.16.104.11
++	$IP route add vrf red 172.16.106.0/24 dev lo src 172.16.104.12
+ 	set +e
+ 
+ 	# removing address from device in vrf should only remove route from vrf table
++	echo "    Regular FIB info"
++
+ 	$IP addr del dev dummy2 172.16.104.11/24
+ 	$IP ro ls vrf red | grep -q 172.16.105.0/24
+ 	log_test $? 1 "Route removed from VRF when source address deleted"
+@@ -1646,6 +1654,35 @@ ipv4_del_addr_test()
+ 	$IP ro ls vrf red | grep -q 172.16.105.0/24
+ 	log_test $? 0 "Route in VRF is not removed by address delete"
+ 
++	# removing address from device in vrf should only remove route from vrf
++	# table even when the associated fib info only differs in table ID
++	echo "    Identical FIB info with different table ID"
++
++	$IP addr del dev dummy2 172.16.104.12/24
++	$IP ro ls vrf red | grep -q 172.16.106.0/24
++	log_test $? 1 "Route removed from VRF when source address deleted"
++
++	$IP ro ls | grep -q 172.16.106.0/24
++	log_test $? 0 "Route in default VRF not removed"
++
++	$IP addr add dev dummy2 172.16.104.12/24
++	$IP route add vrf red 172.16.106.0/24 dev lo src 172.16.104.12
++
++	$IP addr del dev dummy1 172.16.104.12/24
++	$IP ro ls | grep -q 172.16.106.0/24
++	log_test $? 1 "Route removed in default VRF when source address deleted"
++
++	$IP ro ls vrf red | grep -q 172.16.106.0/24
++	log_test $? 0 "Route in VRF is not removed by address delete"
++
++	# removing address from device in default vrf should remove route from
++	# the default vrf even when route was inserted with a table ID of 0.
++	echo "    Table ID 0"
++
++	$IP addr del dev dummy1 172.16.104.13/24
++	$IP ro ls | grep -q 172.16.107.0/24
++	log_test $? 1 "Route removed in default VRF when source address deleted"
++
+ 	$IP li del dummy1
+ 	$IP li del dummy2
+ 	cleanup
+diff --git a/tools/testing/selftests/net/pmtu.sh b/tools/testing/selftests/net/pmtu.sh
+index 694732e4b3448..da6ab300207c0 100755
+--- a/tools/testing/selftests/net/pmtu.sh
++++ b/tools/testing/selftests/net/pmtu.sh
+@@ -671,10 +671,12 @@ setup_xfrm() {
+ }
+ 
+ setup_nettest_xfrm() {
+-	which nettest >/dev/null
+-	if [ $? -ne 0 ]; then
+-		echo "'nettest' command not found; skipping tests"
+-	        return 1
++	if ! which nettest >/dev/null; then
++		PATH=$PWD:$PATH
++		if ! which nettest >/dev/null; then
++			echo "'nettest' command not found; skipping tests"
++			return 1
++		fi
+ 	fi
+ 
+ 	[ ${1} -eq 6 ] && proto="-6" || proto=""
+diff --git a/tools/testing/selftests/net/rtnetlink.sh b/tools/testing/selftests/net/rtnetlink.sh
+index c9ce3dfa42ee7..c3a905923ef29 100755
+--- a/tools/testing/selftests/net/rtnetlink.sh
++++ b/tools/testing/selftests/net/rtnetlink.sh
+@@ -782,7 +782,7 @@ kci_test_ipsec_offload()
+ 	    tmpl proto esp src $srcip dst $dstip spi 9 \
+ 	    mode transport reqid 42
+ 	check_err $?
+-	ip x p add dir out src $dstip/24 dst $srcip/24 \
++	ip x p add dir in src $dstip/24 dst $srcip/24 \
+ 	    tmpl proto esp src $dstip dst $srcip spi 9 \
+ 	    mode transport reqid 42
+ 	check_err $?