[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/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 {
	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);
int __io_run_local_work(struct io_ring_ctx *ctx, bool *locked);
int io_run_local_work(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, bool allow_local);
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, bool *dont_use);
void io_req_task_complete(struct io_kiocb *req, bool *locked);
void io_req_task_queue_fail(struct io_kiocb *req, int ret);
void io_req_task_submit(struct io_kiocb *req, bool *locked);
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, bool *locked);
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_put_task(struct task_struct *task, int nr);
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);

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

#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)
{
	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);
}

/* requires smb_mb() prior, see wq_has_sleeper() */
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 (waitqueue_active(&ctx->cq_wait))
		__wake_up(&ctx->cq_wait, TASK_NORMAL, 0,
				poll_to_key(EPOLL_URING_WAKE | EPOLLIN));
}

static inline void io_cqring_wake(struct io_ring_ctx *ctx)
{
	smp_mb();
	__io_cqring_wake(ctx);
}

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;

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

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();
	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 test_thread_flag(TIF_NOTIFY_SIGNAL) ||
		!wq_list_empty(&ctx->work_llist);
}

static inline int io_run_task_work_ctx(struct io_ring_ctx *ctx)
{
	int ret = 0;
	int ret2;

	if (ctx->flags & IORING_SETUP_DEFER_TASKRUN)
		ret = io_run_local_work(ctx);

	/* want to run this after in case more is added */
	ret2 = io_run_task_work();

	/* Try propagate error in favour of if tasks were run,
	 * but still make sure to run them if requested
	 */
	if (ret >= 0)
		ret += ret2;

	return ret;
}

static inline int io_run_local_work_locked(struct io_ring_ctx *ctx)
{
	bool locked;
	int ret;

	if (llist_empty(&ctx->work_llist))
		return 0;

	locked = true;
	ret = __io_run_local_work(ctx, &locked);
	/* shouldn't happen! */
	if (WARN_ON_ONCE(!locked))
		mutex_lock(&ctx->uring_lock);
	return ret;
}

static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked)
{
	if (!*locked) {
		mutex_lock(&ctx->uring_lock);
		*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))
		__io_commit_cqring_flush(ctx);
}

/* must to be called somewhat shortly after putting a request */
static inline void io_put_task(struct task_struct *task, int nr)
{
	if (likely(task == current))
		task->io_uring->cached_refs += nr;
	else
		__io_put_task(task, nr);
}

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;
}

static inline bool io_alloc_req_refill(struct io_ring_ctx *ctx)
{
	if (unlikely(io_req_cache_empty(ctx)))
		return __io_alloc_req_refill(ctx);
	return true;
}

static inline struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
{
	struct io_wq_work_node *node;

	node = wq_stack_extract(&ctx->submit_state.free_list);
	return container_of(node, struct io_kiocb, comp_list);
}

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>
ab1c84d8	6	#include <linux/io_uring_types.h>
44648532	7	#include <uapi/linux/eventpoll.h>
ab1c84d8	8	#include "io-wq.h"
a6b21fbb	9	#include "slist.h"
ab1c84d8	10	#include "filetable.h"
de23077e	11
f3b44f92 JA	12	#ifndef CREATE_TRACE_POINTS
	13	#include <trace/events/io_uring.h>
	14	#endif
	15
97b388d7 JA	16	enum {
	17	IOU_OK = 0,
	18	IOU_ISSUE_SKIP_COMPLETE = -EIOCBQUEUED,
114eccdf DY	19
114eccdf DY	20	/*
91482864 PB	21	* Intended only when both IO_URING_F_MULTISHOT is passed
91482864 PB	22	* to indicate to the poll runner that multishot should be
114eccdf DY	23	* removed and the result is set on req->cqe.res.
	24	*/
	25	IOU_STOP_MULTISHOT = -ECANCELED,
97b388d7 JA	26	};
97b388d7 JA	27
aa1df3a3	28	struct io_uring_cqe __io_get_cqe(struct io_ring_ctx ctx, bool overflow);
68494a65	29	bool io_req_cqe_overflow(struct io_kiocb *req);
c0e0d6ba	30	int io_run_task_work_sig(struct io_ring_ctx *ctx);
b3026767	31	int __io_run_local_work(struct io_ring_ctx ctx, bool locked);
c0e0d6ba	32	int io_run_local_work(struct io_ring_ctx *ctx);
973fc83f	33	void io_req_defer_failed(struct io_kiocb *req, s32 res);
1bec951c	34	void io_req_complete_post(struct io_kiocb *req, unsigned issue_flags);
b529c96a	35	bool io_post_aux_cqe(struct io_ring_ctx *ctx, u64 user_data, s32 res, u32 cflags);
9b8c5475 DY	36	bool io_aux_cqe(struct io_ring_ctx *ctx, bool defer, u64 user_data, s32 res, u32 cflags,
9b8c5475 DY	37	bool allow_overflow);
9046c641 PB	38	void __io_commit_cqring_flush(struct io_ring_ctx *ctx);
	39
	40	struct page *io_pin_pages(unsigned long ubuf, unsigned long len, int npages);
	41
	42	struct file io_file_get_normal(struct io_kiocb req, int fd);
	43	struct file io_file_get_fixed(struct io_kiocb req, int fd,
	44	unsigned issue_flags);
	45
f6b543fd JA	46	static inline bool io_req_ffs_set(struct io_kiocb *req)
	47	{
	48	return req->flags & REQ_F_FIXED_FILE;
	49	}
	50
e52d2e58	51	void __io_req_task_work_add(struct io_kiocb *req, bool allow_local);
9046c641 PB	52	bool io_is_uring_fops(struct file *file);
9046c641 PB	53	bool io_alloc_async_data(struct io_kiocb *req);
9046c641 PB	54	void io_req_task_queue(struct io_kiocb *req);
	55	void io_queue_iowq(struct io_kiocb req, bool dont_use);
	56	void io_req_task_complete(struct io_kiocb req, bool locked);
	57	void io_req_task_queue_fail(struct io_kiocb *req, int ret);
	58	void io_req_task_submit(struct io_kiocb req, bool locked);
	59	void tctx_task_work(struct callback_head *cb);
	60	__cold void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
	61	int io_uring_alloc_task_context(struct task_struct *task,
	62	struct io_ring_ctx *ctx);
	63
	64	int io_poll_issue(struct io_kiocb req, bool locked);
	65	int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr);
	66	int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin);
	67	void io_free_batch_list(struct io_ring_ctx ctx, struct io_wq_work_node node);
	68	int io_req_prep_async(struct io_kiocb *req);
	69
	70	struct io_wq_work io_wq_free_work(struct io_wq_work work);
	71	void io_wq_submit_work(struct io_wq_work *work);
	72
	73	void io_free_req(struct io_kiocb *req);
	74	void io_queue_next(struct io_kiocb *req);
e70cb608	75	void __io_put_task(struct task_struct *task, int nr);
63809137	76	void io_task_refs_refill(struct io_uring_task *tctx);
bd1a3783	77	bool __io_alloc_req_refill(struct io_ring_ctx *ctx);
9046c641 PB	78
	79	bool io_match_task_safe(struct io_kiocb head, struct task_struct task,
	80	bool cancel_all);
	81
e52d2e58 PB	82	static inline void io_req_task_work_add(struct io_kiocb *req)
	83	{
	84	__io_req_task_work_add(req, true);
	85	}
	86
9046c641 PB	87	#define io_for_each_link(pos, head) \
9046c641 PB	88	for (pos = (head); pos; pos = pos->link)
f3b44f92	89
25399321 PB	90	void io_cq_unlock_post(struct io_ring_ctx *ctx);
25399321 PB	91
aa1df3a3 PB	92	static inline struct io_uring_cqe io_get_cqe_overflow(struct io_ring_ctx ctx,
aa1df3a3 PB	93	bool overflow)
f3b44f92 JA	94	{
	95	if (likely(ctx->cqe_cached < ctx->cqe_sentinel)) {
	96	struct io_uring_cqe *cqe = ctx->cqe_cached;
	97
f3b44f92 JA	98	ctx->cached_cq_tail++;
f3b44f92 JA	99	ctx->cqe_cached++;
b3659a65 PB	100	if (ctx->flags & IORING_SETUP_CQE32)
b3659a65 PB	101	ctx->cqe_cached++;
f3b44f92 JA	102	return cqe;
	103	}
	104
aa1df3a3 PB	105	return __io_get_cqe(ctx, overflow);
	106	}
	107
	108	static inline struct io_uring_cqe io_get_cqe(struct io_ring_ctx ctx)
	109	{
	110	return io_get_cqe_overflow(ctx, false);
f3b44f92 JA	111	}
	112
	113	static inline bool __io_fill_cqe_req(struct io_ring_ctx *ctx,
	114	struct io_kiocb *req)
	115	{
	116	struct io_uring_cqe *cqe;
	117
e8c328c3 PB	118	/*
	119	* If we can't get a cq entry, userspace overflowed the
	120	* submission (by quite a lot). Increment the overflow count in
	121	* the ring.
	122	*/
	123	cqe = io_get_cqe(ctx);
	124	if (unlikely(!cqe))
f66f7342	125	return false;
e0486f3f DY	126
	127	trace_io_uring_complete(req->ctx, req, req->cqe.user_data,
	128	req->cqe.res, req->cqe.flags,
	129	(req->flags & REQ_F_CQE32_INIT) ? req->extra1 : 0,
	130	(req->flags & REQ_F_CQE32_INIT) ? req->extra2 : 0);
	131
e8c328c3 PB	132	memcpy(cqe, &req->cqe, sizeof(*cqe));
	133
	134	if (ctx->flags & IORING_SETUP_CQE32) {
f3b44f92 JA	135	u64 extra1 = 0, extra2 = 0;
	136
	137	if (req->flags & REQ_F_CQE32_INIT) {
	138	extra1 = req->extra1;
	139	extra2 = req->extra2;
	140	}
	141
e8c328c3 PB	142	WRITE_ONCE(cqe->big_cqe[0], extra1);
e8c328c3 PB	143	WRITE_ONCE(cqe->big_cqe[1], extra2);
f3b44f92	144	}
e8c328c3	145	return true;
f3b44f92 JA	146	}
f3b44f92 JA	147
f66f7342 PB	148	static inline bool io_fill_cqe_req(struct io_ring_ctx *ctx,
	149	struct io_kiocb *req)
	150	{
	151	if (likely(__io_fill_cqe_req(ctx, req)))
	152	return true;
	153	return io_req_cqe_overflow(req);
	154	}
	155
531113bb JA	156	static inline void req_set_fail(struct io_kiocb *req)
	157	{
	158	req->flags \|= REQ_F_FAIL;
	159	if (req->flags & REQ_F_CQE_SKIP) {
	160	req->flags &= ~REQ_F_CQE_SKIP;
	161	req->flags \|= REQ_F_SKIP_LINK_CQES;
	162	}
	163	}
	164
de23077e JA	165	static inline void io_req_set_res(struct io_kiocb *req, s32 res, u32 cflags)
	166	{
	167	req->cqe.res = res;
	168	req->cqe.flags = cflags;
	169	}
	170
99f15d8d JA	171	static inline bool req_has_async_data(struct io_kiocb *req)
	172	{
	173	return req->flags & REQ_F_ASYNC_DATA;
	174	}
	175
531113bb JA	176	static inline void io_put_file(struct file *file)
	177	{
	178	if (file)
	179	fput(file);
	180	}
	181
cd40cae2 JA	182	static inline void io_ring_submit_unlock(struct io_ring_ctx *ctx,
	183	unsigned issue_flags)
	184	{
	185	lockdep_assert_held(&ctx->uring_lock);
	186	if (issue_flags & IO_URING_F_UNLOCKED)
	187	mutex_unlock(&ctx->uring_lock);
	188	}
	189
	190	static inline void io_ring_submit_lock(struct io_ring_ctx *ctx,
	191	unsigned issue_flags)
	192	{
	193	/*
	194	* "Normal" inline submissions always hold the uring_lock, since we
	195	* grab it from the system call. Same is true for the SQPOLL offload.
	196	* The only exception is when we've detached the request and issue it
	197	* from an async worker thread, grab the lock for that case.
	198	*/
	199	if (issue_flags & IO_URING_F_UNLOCKED)
	200	mutex_lock(&ctx->uring_lock);
	201	lockdep_assert_held(&ctx->uring_lock);
	202	}
	203
f9ead18c JA	204	static inline void io_commit_cqring(struct io_ring_ctx *ctx)
	205	{
	206	/* order cqe stores with ring update */
	207	smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
	208	}
	209
fc86f9d3 PB	210	/* requires smb_mb() prior, see wq_has_sleeper() */
fc86f9d3 PB	211	static inline void __io_cqring_wake(struct io_ring_ctx *ctx)
f3b44f92 JA	212	{
f3b44f92 JA	213	/*
44648532 JA	214	* Trigger waitqueue handler on all waiters on our waitqueue. This
	215	* won't necessarily wake up all the tasks, io_should_wake() will make
	216	* that decision.
	217	*
	218	* Pass in EPOLLIN\|EPOLL_URING_WAKE as the poll wakeup key. The latter
	219	* set in the mask so that if we recurse back into our own poll
	220	* waitqueue handlers, we know we have a dependency between eventfd or
	221	* epoll and should terminate multishot poll at that point.
f3b44f92	222	*/
fc86f9d3	223	if (waitqueue_active(&ctx->cq_wait))
44648532 JA	224	__wake_up(&ctx->cq_wait, TASK_NORMAL, 0,
44648532 JA	225	poll_to_key(EPOLL_URING_WAKE \| EPOLLIN));
f3b44f92 JA	226	}
f3b44f92 JA	227
fc86f9d3 PB	228	static inline void io_cqring_wake(struct io_ring_ctx *ctx)
	229	{
	230	smp_mb();
	231	__io_cqring_wake(ctx);
	232	}
	233
17437f31 JA	234	static inline bool io_sqring_full(struct io_ring_ctx *ctx)
	235	{
	236	struct io_rings *r = ctx->rings;
	237
	238	return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
	239	}
	240
	241	static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
	242	{
	243	struct io_rings *rings = ctx->rings;
	244
	245	/* make sure SQ entry isn't read before tail */
	246	return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
	247	}
	248
c0e0d6ba	249	static inline int io_run_task_work(void)
17437f31	250	{
7cfe7a09 JA	251	/*
	252	* Always check-and-clear the task_work notification signal. With how
	253	* signaling works for task_work, we can find it set with nothing to
	254	* run. We need to clear it for that case, like get_signal() does.
	255	*/
	256	if (test_thread_flag(TIF_NOTIFY_SIGNAL))
	257	clear_notify_signal();
46a525e1	258	if (task_work_pending(current)) {
17437f31	259	__set_current_state(TASK_RUNNING);
46a525e1	260	task_work_run();
c0e0d6ba	261	return 1;
17437f31 JA	262	}
17437f31 JA	263
c0e0d6ba DY	264	return 0;
	265	}
	266
dac6a0ea JA	267	static inline bool io_task_work_pending(struct io_ring_ctx *ctx)
	268	{
	269	return test_thread_flag(TIF_NOTIFY_SIGNAL) \|\|
	270	!wq_list_empty(&ctx->work_llist);
	271	}
	272
c0e0d6ba DY	273	static inline int io_run_task_work_ctx(struct io_ring_ctx *ctx)
	274	{
	275	int ret = 0;
	276	int ret2;
	277
	278	if (ctx->flags & IORING_SETUP_DEFER_TASKRUN)
	279	ret = io_run_local_work(ctx);
	280
	281	/* want to run this after in case more is added */
	282	ret2 = io_run_task_work();
	283
	284	/* Try propagate error in favour of if tasks were run,
	285	* but still make sure to run them if requested
	286	*/
	287	if (ret >= 0)
	288	ret += ret2;
	289
	290	return ret;
17437f31 JA	291	}
17437f31 JA	292
44f87745 PB	293	static inline int io_run_local_work_locked(struct io_ring_ctx *ctx)
44f87745 PB	294	{
b3026767 DY	295	bool locked;
	296	int ret;
	297
44f87745 PB	298	if (llist_empty(&ctx->work_llist))
44f87745 PB	299	return 0;
b3026767 DY	300
	301	locked = true;
	302	ret = __io_run_local_work(ctx, &locked);
	303	/* shouldn't happen! */
	304	if (WARN_ON_ONCE(!locked))
	305	mutex_lock(&ctx->uring_lock);
	306	return ret;
44f87745 PB	307	}
44f87745 PB	308
aa1e90f6 PB	309	static inline void io_tw_lock(struct io_ring_ctx ctx, bool locked)
	310	{
	311	if (!*locked) {
	312	mutex_lock(&ctx->uring_lock);
	313	*locked = true;
	314	}
	315	}
	316
9da070b1 PB	317	/*
	318	* Don't complete immediately but use deferred completion infrastructure.
	319	* Protected by ->uring_lock and can only be used either with
	320	* IO_URING_F_COMPLETE_DEFER or inside a tw handler holding the mutex.
	321	*/
	322	static inline void io_req_complete_defer(struct io_kiocb *req)
	323	__must_hold(&req->ctx->uring_lock)
aa1e90f6 PB	324	{
	325	struct io_submit_state *state = &req->ctx->submit_state;
	326
9da070b1 PB	327	lockdep_assert_held(&req->ctx->uring_lock);
9da070b1 PB	328
aa1e90f6 PB	329	wq_list_add_tail(&req->comp_list, &state->compl_reqs);
	330	}
	331
46929b08 PB	332	static inline void io_commit_cqring_flush(struct io_ring_ctx *ctx)
	333	{
	334	if (unlikely(ctx->off_timeout_used \|\| ctx->drain_active \|\| ctx->has_evfd))
	335	__io_commit_cqring_flush(ctx);
	336	}
	337
e70cb608 PB	338	/* must to be called somewhat shortly after putting a request */
	339	static inline void io_put_task(struct task_struct *task, int nr)
	340	{
	341	if (likely(task == current))
	342	task->io_uring->cached_refs += nr;
	343	else
	344	__io_put_task(task, nr);
	345	}
	346
63809137 PB	347	static inline void io_get_task_refs(int nr)
	348	{
	349	struct io_uring_task *tctx = current->io_uring;
	350
	351	tctx->cached_refs -= nr;
	352	if (unlikely(tctx->cached_refs < 0))
	353	io_task_refs_refill(tctx);
	354	}
	355
bd1a3783 PB	356	static inline bool io_req_cache_empty(struct io_ring_ctx *ctx)
	357	{
	358	return !ctx->submit_state.free_list.next;
	359	}
	360
	361	static inline bool io_alloc_req_refill(struct io_ring_ctx *ctx)
	362	{
	363	if (unlikely(io_req_cache_empty(ctx)))
	364	return __io_alloc_req_refill(ctx);
	365	return true;
	366	}
	367
	368	static inline struct io_kiocb io_alloc_req(struct io_ring_ctx ctx)
	369	{
	370	struct io_wq_work_node *node;
	371
	372	node = wq_stack_extract(&ctx->submit_state.free_list);
	373	return container_of(node, struct io_kiocb, comp_list);
	374	}
	375
76de6749 PB	376	static inline bool io_allowed_run_tw(struct io_ring_ctx *ctx)
76de6749 PB	377	{
6567506b PB	378	return likely(!(ctx->flags & IORING_SETUP_DEFER_TASKRUN) \|\|
6567506b PB	379	ctx->submitter_task == current);
76de6749 PB	380	}
76de6749 PB	381
833b5dff PB	382	static inline void io_req_queue_tw_complete(struct io_kiocb *req, s32 res)
	383	{
	384	io_req_set_res(req, res, 0);
	385	req->io_task_work.func = io_req_task_complete;
	386	io_req_task_work_add(req);
	387	}
	388
de23077e	389	#endif