[linux-block.git] / io_uring / io_uring.h

#ifndef IOU_CORE_H
#define IOU_CORE_H

#include <linux/errno.h>
#include <linux/lockdep.h>
#include <linux/resume_user_mode.h>
#include <linux/kasan.h>
#include <linux/io_uring_types.h>
#include <uapi/linux/eventpoll.h>
#include "io-wq.h"
#include "slist.h"
#include "filetable.h"

#ifndef CREATE_TRACE_POINTS
#include <trace/events/io_uring.h>
#endif

enum {
	/* don't use deferred task_work */
	IOU_F_TWQ_FORCE_NORMAL			= 1,

	/*
	 * A hint to not wake right away but delay until there are enough of
	 * tw's queued to match the number of CQEs the task is waiting for.
	 *
	 * Must not be used wirh requests generating more than one CQE.
	 * It's also ignored unless IORING_SETUP_DEFER_TASKRUN is set.
	 */
	IOU_F_TWQ_LAZY_WAKE			= 2,
};

enum {
	IOU_OK			= 0,
	IOU_ISSUE_SKIP_COMPLETE	= -EIOCBQUEUED,

	/*
	 * Intended only when both IO_URING_F_MULTISHOT is passed
	 * to indicate to the poll runner that multishot should be
	 * removed and the result is set on req->cqe.res.
	 */
	IOU_STOP_MULTISHOT	= -ECANCELED,
};

struct io_uring_cqe *__io_get_cqe(struct io_ring_ctx *ctx, bool overflow);
bool io_req_cqe_overflow(struct io_kiocb *req);
int io_run_task_work_sig(struct io_ring_ctx *ctx);
void io_req_defer_failed(struct io_kiocb *req, s32 res);
void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags);
bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags);
bool io_aux_cqe(struct io_ring_ctx *ctx, bool defer, u64 user_data, s32 res, u32 cflags,
		bool allow_overflow);
void __io_commit_cqring_flush(struct io_ring_ctx *ctx);

struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages);

struct file *io_file_get_normal(struct io_kiocb *req, int fd);
struct file *io_file_get_fixed(struct io_kiocb *req, int fd,
			       unsigned issue_flags);

static inline bool io_req_ffs_set(struct io_kiocb *req)
{
	return req->flags & REQ_F_FIXED_FILE;
}

void __io_req_task_work_add(struct io_kiocb *req, unsigned flags);
bool io_is_uring_fops(struct file *file);
bool io_alloc_async_data(struct io_kiocb *req);
void io_req_task_queue(struct io_kiocb *req);
void io_queue_iowq(struct io_kiocb *req, struct io_tw_state *ts_dont_use);
void io_req_task_complete(struct io_kiocb *req, struct io_tw_state *ts);
void io_req_task_queue_fail(struct io_kiocb *req, int ret);
void io_req_task_submit(struct io_kiocb *req, struct io_tw_state *ts);
void tctx_task_work(struct callback_head *cb);
__cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
int io_uring_alloc_task_context(struct task_struct *task,
				struct io_ring_ctx *ctx);

int io_poll_issue(struct io_kiocb *req, struct io_tw_state *ts);
int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr);
int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin);
void io_free_batch_list(struct io_ring_ctx *ctx, struct io_wq_work_node *node);
int io_req_prep_async(struct io_kiocb *req);

struct io_wq_work *io_wq_free_work(struct io_wq_work *work);
void io_wq_submit_work(struct io_wq_work *work);

void io_free_req(struct io_kiocb *req);
void io_queue_next(struct io_kiocb *req);
void io_task_refs_refill(struct io_uring_task *tctx);
bool __io_alloc_req_refill(struct io_ring_ctx *ctx);

bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
			bool cancel_all);

#define io_lockdep_assert_cq_locked(ctx)				\
	do {								\
		if (ctx->flags & IORING_SETUP_IOPOLL) {			\
			lockdep_assert_held(&ctx->uring_lock);		\
		} else if (!ctx->task_complete) {			\
			lockdep_assert_held(&ctx->completion_lock);	\
		} else if (ctx->submitter_task->flags & PF_EXITING) {	\
			lockdep_assert(current_work());			\
		} else {						\
			lockdep_assert(current == ctx->submitter_task);	\
		}							\
	} while (0)

static inline void io_req_task_work_add(struct io_kiocb *req)
{
	__io_req_task_work_add(req, 0);
}

#define io_for_each_link(pos, head) \
	for (pos = (head); pos; pos = pos->link)

void io_cq_unlock_post(struct io_ring_ctx *ctx);

static inline struct io_uring_cqe *io_get_cqe_overflow(struct io_ring_ctx *ctx,
						       bool overflow)
{
	io_lockdep_assert_cq_locked(ctx);

	if (likely(ctx->cqe_cached < ctx->cqe_sentinel)) {
		struct io_uring_cqe *cqe = ctx->cqe_cached;

		ctx->cached_cq_tail++;
		ctx->cqe_cached++;
		if (ctx->flags & IORING_SETUP_CQE32)
			ctx->cqe_cached++;
		return cqe;
	}

	return __io_get_cqe(ctx, overflow);
}

static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx)
{
	return io_get_cqe_overflow(ctx, false);
}

static inline bool __io_fill_cqe_req(struct io_ring_ctx *ctx,
				     struct io_kiocb *req)
{
	struct io_uring_cqe *cqe;

	/*
	 * 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 (unlikely(!cqe))
		return false;

	trace_io_uring_complete(req->ctx, req, req->cqe.user_data,
				req->cqe.res, req->cqe.flags,
				(req->flags & REQ_F_CQE32_INIT) ? req->extra1 : 0,
				(req->flags & REQ_F_CQE32_INIT) ? req->extra2 : 0);

	memcpy(cqe, &req->cqe, sizeof(*cqe));

	if (ctx->flags & IORING_SETUP_CQE32) {
		u64 extra1 = 0, extra2 = 0;

		if (req->flags & REQ_F_CQE32_INIT) {
			extra1 = req->extra1;
			extra2 = req->extra2;
		}

		WRITE_ONCE(cqe->big_cqe[0], extra1);
		WRITE_ONCE(cqe->big_cqe[1], extra2);
	}
	return true;
}

static inline bool io_fill_cqe_req(struct io_ring_ctx *ctx,
				   struct io_kiocb *req)
{
	if (likely(__io_fill_cqe_req(ctx, req)))
		return true;
	return io_req_cqe_overflow(req);
}

static inline void req_set_fail(struct io_kiocb *req)
{
	req->flags |= REQ_F_FAIL;
	if (req->flags & REQ_F_CQE_SKIP) {
		req->flags &= ~REQ_F_CQE_SKIP;
		req->flags |= REQ_F_SKIP_LINK_CQES;
	}
}

static inline void io_req_set_res(struct io_kiocb *req, s32 res, u32 cflags)
{
	req->cqe.res = res;
	req->cqe.flags = cflags;
}

static inline bool req_has_async_data(struct io_kiocb *req)
{
	return req->flags & REQ_F_ASYNC_DATA;
}

static inline void io_put_file(struct file *file)
{
	if (file)
		fput(file);
}

static inline void io_ring_submit_unlock(struct io_ring_ctx *ctx,
					 unsigned issue_flags)
{
	lockdep_assert_held(&ctx->uring_lock);
	if (issue_flags & IO_URING_F_UNLOCKED)
		mutex_unlock(&ctx->uring_lock);
}

static inline void io_ring_submit_lock(struct io_ring_ctx *ctx,
				       unsigned issue_flags)
{
	/*
	 * "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 (issue_flags & IO_URING_F_UNLOCKED)
		mutex_lock(&ctx->uring_lock);
	lockdep_assert_held(&ctx->uring_lock);
}

static inline void io_commit_cqring(struct io_ring_ctx *ctx)
{
	/* order cqe stores with ring update */
	smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
}

static inline void io_poll_wq_wake(struct io_ring_ctx *ctx)
{
	if (wq_has_sleeper(&ctx->poll_wq))
		__wake_up(&ctx->poll_wq, TASK_NORMAL, 0,
				poll_to_key(EPOLL_URING_WAKE | EPOLLIN));
}

static inline void io_cqring_wake(struct io_ring_ctx *ctx)
{
	/*
	 * Trigger waitqueue handler on all waiters on our waitqueue. This
	 * won't necessarily wake up all the tasks, io_should_wake() will make
	 * that decision.
	 *
	 * Pass in EPOLLIN|EPOLL_URING_WAKE as the poll wakeup key. The latter
	 * set in the mask so that if we recurse back into our own poll
	 * waitqueue handlers, we know we have a dependency between eventfd or
	 * epoll and should terminate multishot poll at that point.
	 */
	if (wq_has_sleeper(&ctx->cq_wait))
		__wake_up(&ctx->cq_wait, TASK_NORMAL, 0,
				poll_to_key(EPOLL_URING_WAKE | EPOLLIN));
}

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_sqring_entries(struct io_ring_ctx *ctx)
{
	struct io_rings *rings = ctx->rings;
	unsigned int entries;

	/* make sure SQ entry isn't read before tail */
	entries = smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
	return min(entries, ctx->sq_entries);
}

static inline int io_run_task_work(void)
{
	/*
	 * Always check-and-clear the task_work notification signal. With how
	 * signaling works for task_work, we can find it set with nothing to
	 * run. We need to clear it for that case, like get_signal() does.
	 */
	if (test_thread_flag(TIF_NOTIFY_SIGNAL))
		clear_notify_signal();
	/*
	 * PF_IO_WORKER never returns to userspace, so check here if we have
	 * notify work that needs processing.
	 */
	if (current->flags & PF_IO_WORKER &&
	    test_thread_flag(TIF_NOTIFY_RESUME)) {
		__set_current_state(TASK_RUNNING);
		resume_user_mode_work(NULL);
	}
	if (task_work_pending(current)) {
		__set_current_state(TASK_RUNNING);
		task_work_run();
		return 1;
	}

	return 0;
}

static inline bool io_task_work_pending(struct io_ring_ctx *ctx)
{
	return task_work_pending(current) || !wq_list_empty(&ctx->work_llist);
}

static inline void io_tw_lock(struct io_ring_ctx *ctx, struct io_tw_state *ts)
{
	if (!ts->locked) {
		mutex_lock(&ctx->uring_lock);
		ts->locked = true;
	}
}

/*
 * Don't complete immediately but use deferred completion infrastructure.
 * Protected by ->uring_lock and can only be used either with
 * IO_URING_F_COMPLETE_DEFER or inside a tw handler holding the mutex.
 */
static inline void io_req_complete_defer(struct io_kiocb *req)
	__must_hold(&req->ctx->uring_lock)
{
	struct io_submit_state *state = &req->ctx->submit_state;

	lockdep_assert_held(&req->ctx->uring_lock);

	wq_list_add_tail(&req->comp_list, &state->compl_reqs);
}

static inline void io_commit_cqring_flush(struct io_ring_ctx *ctx)
{
	if (unlikely(ctx->off_timeout_used || ctx->drain_active ||
		     ctx->has_evfd || ctx->poll_activated))
		__io_commit_cqring_flush(ctx);
}

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 inline bool io_req_cache_empty(struct io_ring_ctx *ctx)
{
	return !ctx->submit_state.free_list.next;
}

extern struct kmem_cache *req_cachep;

static inline struct io_kiocb *io_extract_req(struct io_ring_ctx *ctx)
{
	struct io_kiocb *req;

	req = container_of(ctx->submit_state.free_list.next, struct io_kiocb, comp_list);
	kasan_unpoison_object_data(req_cachep, req);
	wq_stack_extract(&ctx->submit_state.free_list);
	return req;
}

static inline bool io_alloc_req(struct io_ring_ctx *ctx, struct io_kiocb **req)
{
	if (unlikely(io_req_cache_empty(ctx))) {
		if (!__io_alloc_req_refill(ctx))
			return false;
	}
	*req = io_extract_req(ctx);
	return true;
}

static inline bool io_allowed_defer_tw_run(struct io_ring_ctx *ctx)
{
	return likely(ctx->submitter_task == current);
}

static inline bool io_allowed_run_tw(struct io_ring_ctx *ctx)
{
	return likely(!(ctx->flags & IORING_SETUP_DEFER_TASKRUN) ||
		      ctx->submitter_task == current);
}

static inline void io_req_queue_tw_complete(struct io_kiocb *req, s32 res)
{
	io_req_set_res(req, res, 0);
	req->io_task_work.func = io_req_task_complete;
	io_req_task_work_add(req);
}

#endif
Commit	Line	Data
de23077e JA	1	#ifndef IOU_CORE_H
	2	#define IOU_CORE_H
	3
	4	#include <linux/errno.h>
cd40cae2	5	#include <linux/lockdep.h>
b5d3ae20	6	#include <linux/resume_user_mode.h>
c1755c25	7	#include <linux/kasan.h>
ab1c84d8	8	#include <linux/io_uring_types.h>
44648532	9	#include <uapi/linux/eventpoll.h>
ab1c84d8	10	#include "io-wq.h"
a6b21fbb	11	#include "slist.h"
ab1c84d8	12	#include "filetable.h"
de23077e	13
f3b44f92 JA	14	#ifndef CREATE_TRACE_POINTS
	15	#include <trace/events/io_uring.h>
	16	#endif
	17
8501fe70 PB	18	enum {
	19	/* don't use deferred task_work */
	20	IOU_F_TWQ_FORCE_NORMAL = 1,
8751d154 PB	21
	22	/*
	23	* A hint to not wake right away but delay until there are enough of
	24	* tw's queued to match the number of CQEs the task is waiting for.
	25	*
	26	* Must not be used wirh requests generating more than one CQE.
	27	* It's also ignored unless IORING_SETUP_DEFER_TASKRUN is set.
	28	*/
	29	IOU_F_TWQ_LAZY_WAKE = 2,
8501fe70 PB	30	};
8501fe70 PB	31
97b388d7 JA	32	enum {
	33	IOU_OK = 0,
	34	IOU_ISSUE_SKIP_COMPLETE = -EIOCBQUEUED,
114eccdf DY	35
114eccdf DY	36	/*
91482864 PB	37	* Intended only when both IO_URING_F_MULTISHOT is passed
91482864 PB	38	* to indicate to the poll runner that multishot should be
114eccdf DY	39	* removed and the result is set on req->cqe.res.
	40	*/
	41	IOU_STOP_MULTISHOT = -ECANCELED,
97b388d7 JA	42	};
97b388d7 JA	43
aa1df3a3	44	struct io_uring_cqe __io_get_cqe(struct io_ring_ctx ctx, bool overflow);
68494a65	45	bool io_req_cqe_overflow(struct io_kiocb *req);
c0e0d6ba	46	int io_run_task_work_sig(struct io_ring_ctx *ctx);
973fc83f	47	void io_req_defer_failed(struct io_kiocb *req, s32 res);
1bec951c	48	void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags);
b529c96a	49	bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags);
9b8c5475 DY	50	bool io_aux_cqe(struct io_ring_ctx *ctx, bool defer, u64 user_data, s32 res, u32 cflags,
9b8c5475 DY	51	bool allow_overflow);
9046c641 PB	52	void __io_commit_cqring_flush(struct io_ring_ctx *ctx);
	53
	54	struct page *io_pin_pages(unsigned long ubuf, unsigned long len, int npages);
	55
	56	struct file io_file_get_normal(struct io_kiocb req, int fd);
	57	struct file io_file_get_fixed(struct io_kiocb req, int fd,
	58	unsigned issue_flags);
	59
f6b543fd JA	60	static inline bool io_req_ffs_set(struct io_kiocb *req)
	61	{
	62	return req->flags & REQ_F_FIXED_FILE;
	63	}
	64
8501fe70	65	void __io_req_task_work_add(struct io_kiocb *req, unsigned flags);
9046c641 PB	66	bool io_is_uring_fops(struct file *file);
9046c641 PB	67	bool io_alloc_async_data(struct io_kiocb *req);
9046c641	68	void io_req_task_queue(struct io_kiocb *req);
a282967c PB	69	void io_queue_iowq(struct io_kiocb req, struct io_tw_state ts_dont_use);
a282967c PB	70	void io_req_task_complete(struct io_kiocb req, struct io_tw_state ts);
9046c641	71	void io_req_task_queue_fail(struct io_kiocb *req, int ret);
a282967c	72	void io_req_task_submit(struct io_kiocb req, struct io_tw_state ts);
9046c641 PB	73	void tctx_task_work(struct callback_head *cb);
	74	__cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
	75	int io_uring_alloc_task_context(struct task_struct *task,
	76	struct io_ring_ctx *ctx);
	77
a282967c	78	int io_poll_issue(struct io_kiocb req, struct io_tw_state ts);
9046c641 PB	79	int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr);
	80	int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin);
	81	void io_free_batch_list(struct io_ring_ctx ctx, struct io_wq_work_node node);
	82	int io_req_prep_async(struct io_kiocb *req);
	83
	84	struct io_wq_work io_wq_free_work(struct io_wq_work work);
	85	void io_wq_submit_work(struct io_wq_work *work);
	86
	87	void io_free_req(struct io_kiocb *req);
	88	void io_queue_next(struct io_kiocb *req);
63809137	89	void io_task_refs_refill(struct io_uring_task *tctx);
bd1a3783	90	bool __io_alloc_req_refill(struct io_ring_ctx *ctx);
9046c641 PB	91
	92	bool io_match_task_safe(struct io_kiocb head, struct task_struct task,
	93	bool cancel_all);
	94
f26cc959 PB	95	#define io_lockdep_assert_cq_locked(ctx) \
	96	do { \
	97	if (ctx->flags & IORING_SETUP_IOPOLL) { \
	98	lockdep_assert_held(&ctx->uring_lock); \
	99	} else if (!ctx->task_complete) { \
	100	lockdep_assert_held(&ctx->completion_lock); \
	101	} else if (ctx->submitter_task->flags & PF_EXITING) { \
	102	lockdep_assert(current_work()); \
	103	} else { \
	104	lockdep_assert(current == ctx->submitter_task); \
	105	} \
	106	} while (0)
	107
e52d2e58 PB	108	static inline void io_req_task_work_add(struct io_kiocb *req)
e52d2e58 PB	109	{
8501fe70	110	__io_req_task_work_add(req, 0);
e52d2e58 PB	111	}
e52d2e58 PB	112
9046c641 PB	113	#define io_for_each_link(pos, head) \
9046c641 PB	114	for (pos = (head); pos; pos = pos->link)
f3b44f92	115
25399321 PB	116	void io_cq_unlock_post(struct io_ring_ctx *ctx);
25399321 PB	117
aa1df3a3 PB	118	static inline struct io_uring_cqe io_get_cqe_overflow(struct io_ring_ctx ctx,
aa1df3a3 PB	119	bool overflow)
f3b44f92	120	{
f26cc959 PB	121	io_lockdep_assert_cq_locked(ctx);
f26cc959 PB	122
f3b44f92 JA	123	if (likely(ctx->cqe_cached < ctx->cqe_sentinel)) {
	124	struct io_uring_cqe *cqe = ctx->cqe_cached;
	125
f3b44f92 JA	126	ctx->cached_cq_tail++;
f3b44f92 JA	127	ctx->cqe_cached++;
b3659a65 PB	128	if (ctx->flags & IORING_SETUP_CQE32)
b3659a65 PB	129	ctx->cqe_cached++;
f3b44f92 JA	130	return cqe;
	131	}
	132
aa1df3a3 PB	133	return __io_get_cqe(ctx, overflow);
	134	}
	135
	136	static inline struct io_uring_cqe io_get_cqe(struct io_ring_ctx ctx)
	137	{
	138	return io_get_cqe_overflow(ctx, false);
f3b44f92 JA	139	}
	140
	141	static inline bool __io_fill_cqe_req(struct io_ring_ctx *ctx,
	142	struct io_kiocb *req)
	143	{
	144	struct io_uring_cqe *cqe;
	145
e8c328c3 PB	146	/*
	147	* If we can't get a cq entry, userspace overflowed the
	148	* submission (by quite a lot). Increment the overflow count in
	149	* the ring.
	150	*/
	151	cqe = io_get_cqe(ctx);
	152	if (unlikely(!cqe))
f66f7342	153	return false;
e0486f3f DY	154
	155	trace_io_uring_complete(req->ctx, req, req->cqe.user_data,
	156	req->cqe.res, req->cqe.flags,
	157	(req->flags & REQ_F_CQE32_INIT) ? req->extra1 : 0,
	158	(req->flags & REQ_F_CQE32_INIT) ? req->extra2 : 0);
	159
e8c328c3 PB	160	memcpy(cqe, &req->cqe, sizeof(*cqe));
	161
	162	if (ctx->flags & IORING_SETUP_CQE32) {
f3b44f92 JA	163	u64 extra1 = 0, extra2 = 0;
	164
	165	if (req->flags & REQ_F_CQE32_INIT) {
	166	extra1 = req->extra1;
	167	extra2 = req->extra2;
	168	}
	169
e8c328c3 PB	170	WRITE_ONCE(cqe->big_cqe[0], extra1);
e8c328c3 PB	171	WRITE_ONCE(cqe->big_cqe[1], extra2);
f3b44f92	172	}
e8c328c3	173	return true;
f3b44f92 JA	174	}
f3b44f92 JA	175
f66f7342 PB	176	static inline bool io_fill_cqe_req(struct io_ring_ctx *ctx,
	177	struct io_kiocb *req)
	178	{
	179	if (likely(__io_fill_cqe_req(ctx, req)))
	180	return true;
	181	return io_req_cqe_overflow(req);
	182	}
	183
531113bb JA	184	static inline void req_set_fail(struct io_kiocb *req)
	185	{
	186	req->flags \|= REQ_F_FAIL;
	187	if (req->flags & REQ_F_CQE_SKIP) {
	188	req->flags &= ~REQ_F_CQE_SKIP;
	189	req->flags \|= REQ_F_SKIP_LINK_CQES;
	190	}
	191	}
	192
de23077e JA	193	static inline void io_req_set_res(struct io_kiocb *req, s32 res, u32 cflags)
	194	{
	195	req->cqe.res = res;
	196	req->cqe.flags = cflags;
	197	}
	198
99f15d8d JA	199	static inline bool req_has_async_data(struct io_kiocb *req)
	200	{
	201	return req->flags & REQ_F_ASYNC_DATA;
	202	}
	203
531113bb JA	204	static inline void io_put_file(struct file *file)
	205	{
	206	if (file)
	207	fput(file);
	208	}
	209
cd40cae2 JA	210	static inline void io_ring_submit_unlock(struct io_ring_ctx *ctx,
	211	unsigned issue_flags)
	212	{
	213	lockdep_assert_held(&ctx->uring_lock);
	214	if (issue_flags & IO_URING_F_UNLOCKED)
	215	mutex_unlock(&ctx->uring_lock);
	216	}
	217
	218	static inline void io_ring_submit_lock(struct io_ring_ctx *ctx,
	219	unsigned issue_flags)
	220	{
	221	/*
	222	* "Normal" inline submissions always hold the uring_lock, since we
	223	* grab it from the system call. Same is true for the SQPOLL offload.
	224	* The only exception is when we've detached the request and issue it
	225	* from an async worker thread, grab the lock for that case.
	226	*/
	227	if (issue_flags & IO_URING_F_UNLOCKED)
	228	mutex_lock(&ctx->uring_lock);
	229	lockdep_assert_held(&ctx->uring_lock);
	230	}
	231
f9ead18c JA	232	static inline void io_commit_cqring(struct io_ring_ctx *ctx)
	233	{
	234	/* order cqe stores with ring update */
	235	smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
	236	}
	237
7b235dd8 PB	238	static inline void io_poll_wq_wake(struct io_ring_ctx *ctx)
7b235dd8 PB	239	{
bca39f39	240	if (wq_has_sleeper(&ctx->poll_wq))
7b235dd8 PB	241	__wake_up(&ctx->poll_wq, TASK_NORMAL, 0,
	242	poll_to_key(EPOLL_URING_WAKE \| EPOLLIN));
	243	}
	244
6e7248ad	245	static inline void io_cqring_wake(struct io_ring_ctx *ctx)
f3b44f92 JA	246	{
f3b44f92 JA	247	/*
44648532 JA	248	* Trigger waitqueue handler on all waiters on our waitqueue. This
	249	* won't necessarily wake up all the tasks, io_should_wake() will make
	250	* that decision.
	251	*
	252	* Pass in EPOLLIN\|EPOLL_URING_WAKE as the poll wakeup key. The latter
	253	* set in the mask so that if we recurse back into our own poll
	254	* waitqueue handlers, we know we have a dependency between eventfd or
	255	* epoll and should terminate multishot poll at that point.
f3b44f92	256	*/
6e7248ad	257	if (wq_has_sleeper(&ctx->cq_wait))
44648532 JA	258	__wake_up(&ctx->cq_wait, TASK_NORMAL, 0,
44648532 JA	259	poll_to_key(EPOLL_URING_WAKE \| EPOLLIN));
f3b44f92 JA	260	}
f3b44f92 JA	261
17437f31 JA	262	static inline bool io_sqring_full(struct io_ring_ctx *ctx)
	263	{
	264	struct io_rings *r = ctx->rings;
	265
	266	return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
	267	}
	268
	269	static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
	270	{
	271	struct io_rings *rings = ctx->rings;
e3ef728f	272	unsigned int entries;
17437f31 JA	273
17437f31 JA	274	/* make sure SQ entry isn't read before tail */
e3ef728f JA	275	entries = smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
e3ef728f JA	276	return min(entries, ctx->sq_entries);
17437f31 JA	277	}
17437f31 JA	278
c0e0d6ba	279	static inline int io_run_task_work(void)
17437f31	280	{
7cfe7a09 JA	281	/*
	282	* Always check-and-clear the task_work notification signal. With how
	283	* signaling works for task_work, we can find it set with nothing to
	284	* run. We need to clear it for that case, like get_signal() does.
	285	*/
	286	if (test_thread_flag(TIF_NOTIFY_SIGNAL))
	287	clear_notify_signal();
b5d3ae20 JA	288	/*
	289	* PF_IO_WORKER never returns to userspace, so check here if we have
	290	* notify work that needs processing.
	291	*/
	292	if (current->flags & PF_IO_WORKER &&
2f2bb1ff JA	293	test_thread_flag(TIF_NOTIFY_RESUME)) {
2f2bb1ff JA	294	__set_current_state(TASK_RUNNING);
b5d3ae20	295	resume_user_mode_work(NULL);
2f2bb1ff	296	}
46a525e1	297	if (task_work_pending(current)) {
17437f31	298	__set_current_state(TASK_RUNNING);
46a525e1	299	task_work_run();
c0e0d6ba	300	return 1;
17437f31 JA	301	}
17437f31 JA	302
c0e0d6ba DY	303	return 0;
	304	}
	305
dac6a0ea JA	306	static inline bool io_task_work_pending(struct io_ring_ctx *ctx)
dac6a0ea JA	307	{
6434ec01	308	return task_work_pending(current) \|\| !wq_list_empty(&ctx->work_llist);
dac6a0ea JA	309	}
dac6a0ea JA	310
a282967c	311	static inline void io_tw_lock(struct io_ring_ctx ctx, struct io_tw_state ts)
aa1e90f6	312	{
a282967c	313	if (!ts->locked) {
aa1e90f6	314	mutex_lock(&ctx->uring_lock);
a282967c	315	ts->locked = true;
aa1e90f6 PB	316	}
	317	}
	318
9da070b1 PB	319	/*
	320	* Don't complete immediately but use deferred completion infrastructure.
	321	* Protected by ->uring_lock and can only be used either with
	322	* IO_URING_F_COMPLETE_DEFER or inside a tw handler holding the mutex.
	323	*/
	324	static inline void io_req_complete_defer(struct io_kiocb *req)
	325	__must_hold(&req->ctx->uring_lock)
aa1e90f6 PB	326	{
	327	struct io_submit_state *state = &req->ctx->submit_state;
	328
9da070b1 PB	329	lockdep_assert_held(&req->ctx->uring_lock);
9da070b1 PB	330
aa1e90f6 PB	331	wq_list_add_tail(&req->comp_list, &state->compl_reqs);
	332	}
	333
46929b08 PB	334	static inline void io_commit_cqring_flush(struct io_ring_ctx *ctx)
46929b08 PB	335	{
bca39f39 PB	336	if (unlikely(ctx->off_timeout_used \|\| ctx->drain_active \|\|
bca39f39 PB	337	ctx->has_evfd \|\| ctx->poll_activated))
46929b08 PB	338	__io_commit_cqring_flush(ctx);
	339	}
	340
63809137 PB	341	static inline void io_get_task_refs(int nr)
	342	{
	343	struct io_uring_task *tctx = current->io_uring;
	344
	345	tctx->cached_refs -= nr;
	346	if (unlikely(tctx->cached_refs < 0))
	347	io_task_refs_refill(tctx);
	348	}
	349
bd1a3783 PB	350	static inline bool io_req_cache_empty(struct io_ring_ctx *ctx)
	351	{
	352	return !ctx->submit_state.free_list.next;
	353	}
	354
c1755c25 BL	355	extern struct kmem_cache *req_cachep;
c1755c25 BL	356
c8576f3e	357	static inline struct io_kiocb io_extract_req(struct io_ring_ctx ctx)
bd1a3783	358	{
c1755c25	359	struct io_kiocb *req;
bd1a3783	360
c1755c25 BL	361	req = container_of(ctx->submit_state.free_list.next, struct io_kiocb, comp_list);
	362	kasan_unpoison_object_data(req_cachep, req);
	363	wq_stack_extract(&ctx->submit_state.free_list);
	364	return req;
bd1a3783 PB	365	}
bd1a3783 PB	366
c8576f3e PB	367	static inline bool io_alloc_req(struct io_ring_ctx ctx, struct io_kiocb *req)
	368	{
	369	if (unlikely(io_req_cache_empty(ctx))) {
	370	if (!__io_alloc_req_refill(ctx))
	371	return false;
	372	}
	373	*req = io_extract_req(ctx);
	374	return true;
	375	}
	376
140102ae PB	377	static inline bool io_allowed_defer_tw_run(struct io_ring_ctx *ctx)
	378	{
	379	return likely(ctx->submitter_task == current);
	380	}
	381
76de6749 PB	382	static inline bool io_allowed_run_tw(struct io_ring_ctx *ctx)
76de6749 PB	383	{
6567506b PB	384	return likely(!(ctx->flags & IORING_SETUP_DEFER_TASKRUN) \|\|
6567506b PB	385	ctx->submitter_task == current);
76de6749 PB	386	}
76de6749 PB	387
833b5dff PB	388	static inline void io_req_queue_tw_complete(struct io_kiocb *req, s32 res)
	389	{
	390	io_req_set_res(req, res, 0);
	391	req->io_task_work.func = io_req_task_complete;
	392	io_req_task_work_add(req);
	393	}
	394
de23077e	395	#endif