xref: /openbmc/linux/io_uring/timeout.c (revision 7587cdef) 
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/kernel.h>
3 #include <linux/errno.h>
4 #include <linux/file.h>
5 #include <linux/io_uring.h>
6 
7 #include <trace/events/io_uring.h>
8 
9 #include <uapi/linux/io_uring.h>
10 
11 #include "io_uring.h"
12 #include "refs.h"
13 #include "cancel.h"
14 #include "timeout.h"
15 
16 struct io_timeout {
17 	struct file			*file;
18 	u32				off;
19 	u32				target_seq;
20 	struct list_head		list;
21 	/* head of the link, used by linked timeouts only */
22 	struct io_kiocb			*head;
23 	/* for linked completions */
24 	struct io_kiocb			*prev;
25 };
26 
27 struct io_timeout_rem {
28 	struct file			*file;
29 	u64				addr;
30 
31 	/* timeout update */
32 	struct timespec64		ts;
33 	u32				flags;
34 	bool				ltimeout;
35 };
36 
37 static inline bool io_is_timeout_noseq(struct io_kiocb *req)
38 {
39 	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
40 
41 	return !timeout->off;
42 }
43 
44 static inline void io_put_req(struct io_kiocb *req)
45 {
46 	if (req_ref_put_and_test(req)) {
47 		io_queue_next(req);
48 		io_free_req(req);
49 	}
50 }
51 
52 static bool io_kill_timeout(struct io_kiocb *req, int status)
53 	__must_hold(&req->ctx->completion_lock)
54 	__must_hold(&req->ctx->timeout_lock)
55 {
56 	struct io_timeout_data *io = req->async_data;
57 
58 	if (hrtimer_try_to_cancel(&io->timer) != -1) {
59 		struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
60 
61 		if (status)
62 			req_set_fail(req);
63 		atomic_set(&req->ctx->cq_timeouts,
64 			atomic_read(&req->ctx->cq_timeouts) + 1);
65 		list_del_init(&timeout->list);
66 		io_req_tw_post_queue(req, status, 0);
67 		return true;
68 	}
69 	return false;
70 }
71 
72 __cold void io_flush_timeouts(struct io_ring_ctx *ctx)
73 	__must_hold(&ctx->completion_lock)
74 {
75 	u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
76 	struct io_timeout *timeout, *tmp;
77 
78 	spin_lock_irq(&ctx->timeout_lock);
79 	list_for_each_entry_safe(timeout, tmp, &ctx->timeout_list, list) {
80 		struct io_kiocb *req = cmd_to_io_kiocb(timeout);
81 		u32 events_needed, events_got;
82 
83 		if (io_is_timeout_noseq(req))
84 			break;
85 
86 		/*
87 		 * Since seq can easily wrap around over time, subtract
88 		 * the last seq at which timeouts were flushed before comparing.
89 		 * Assuming not more than 2^31-1 events have happened since,
90 		 * these subtractions won't have wrapped, so we can check if
91 		 * target is in [last_seq, current_seq] by comparing the two.
92 		 */
93 		events_needed = timeout->target_seq - ctx->cq_last_tm_flush;
94 		events_got = seq - ctx->cq_last_tm_flush;
95 		if (events_got < events_needed)
96 			break;
97 
98 		io_kill_timeout(req, 0);
99 	}
100 	ctx->cq_last_tm_flush = seq;
101 	spin_unlock_irq(&ctx->timeout_lock);
102 }
103 
104 static void io_req_tw_fail_links(struct io_kiocb *link, bool *locked)
105 {
106 	io_tw_lock(link->ctx, locked);
107 	while (link) {
108 		struct io_kiocb *nxt = link->link;
109 		long res = -ECANCELED;
110 
111 		if (link->flags & REQ_F_FAIL)
112 			res = link->cqe.res;
113 		link->link = NULL;
114 		io_req_set_res(link, res, 0);
115 		io_req_task_complete(link, locked);
116 		link = nxt;
117 	}
118 }
119 
120 static void io_fail_links(struct io_kiocb *req)
121 	__must_hold(&req->ctx->completion_lock)
122 {
123 	struct io_kiocb *link = req->link;
124 	bool ignore_cqes = req->flags & REQ_F_SKIP_LINK_CQES;
125 
126 	if (!link)
127 		return;
128 
129 	while (link) {
130 		if (ignore_cqes)
131 			link->flags |= REQ_F_CQE_SKIP;
132 		else
133 			link->flags &= ~REQ_F_CQE_SKIP;
134 		trace_io_uring_fail_link(req, link);
135 		link = link->link;
136 	}
137 
138 	link = req->link;
139 	link->io_task_work.func = io_req_tw_fail_links;
140 	io_req_task_work_add(link);
141 	req->link = NULL;
142 }
143 
144 static inline void io_remove_next_linked(struct io_kiocb *req)
145 {
146 	struct io_kiocb *nxt = req->link;
147 
148 	req->link = nxt->link;
149 	nxt->link = NULL;
150 }
151 
152 void io_disarm_next(struct io_kiocb *req)
153 	__must_hold(&req->ctx->completion_lock)
154 {
155 	struct io_kiocb *link = NULL;
156 
157 	if (req->flags & REQ_F_ARM_LTIMEOUT) {
158 		link = req->link;
159 		req->flags &= ~REQ_F_ARM_LTIMEOUT;
160 		if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
161 			io_remove_next_linked(req);
162 			io_req_tw_post_queue(link, -ECANCELED, 0);
163 		}
164 	} else if (req->flags & REQ_F_LINK_TIMEOUT) {
165 		struct io_ring_ctx *ctx = req->ctx;
166 
167 		spin_lock_irq(&ctx->timeout_lock);
168 		link = io_disarm_linked_timeout(req);
169 		spin_unlock_irq(&ctx->timeout_lock);
170 		if (link)
171 			io_req_tw_post_queue(link, -ECANCELED, 0);
172 	}
173 	if (unlikely((req->flags & REQ_F_FAIL) &&
174 		     !(req->flags & REQ_F_HARDLINK)))
175 		io_fail_links(req);
176 }
177 
178 struct io_kiocb *__io_disarm_linked_timeout(struct io_kiocb *req,
179 					    struct io_kiocb *link)
180 	__must_hold(&req->ctx->completion_lock)
181 	__must_hold(&req->ctx->timeout_lock)
182 {
183 	struct io_timeout_data *io = link->async_data;
184 	struct io_timeout *timeout = io_kiocb_to_cmd(link, struct io_timeout);
185 
186 	io_remove_next_linked(req);
187 	timeout->head = NULL;
188 	if (hrtimer_try_to_cancel(&io->timer) != -1) {
189 		list_del(&timeout->list);
190 		return link;
191 	}
192 
193 	return NULL;
194 }
195 
196 static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
197 {
198 	struct io_timeout_data *data = container_of(timer,
199 						struct io_timeout_data, timer);
200 	struct io_kiocb *req = data->req;
201 	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
202 	struct io_ring_ctx *ctx = req->ctx;
203 	unsigned long flags;
204 
205 	spin_lock_irqsave(&ctx->timeout_lock, flags);
206 	list_del_init(&timeout->list);
207 	atomic_set(&req->ctx->cq_timeouts,
208 		atomic_read(&req->ctx->cq_timeouts) + 1);
209 	spin_unlock_irqrestore(&ctx->timeout_lock, flags);
210 
211 	if (!(data->flags & IORING_TIMEOUT_ETIME_SUCCESS))
212 		req_set_fail(req);
213 
214 	io_req_set_res(req, -ETIME, 0);
215 	req->io_task_work.func = io_req_task_complete;
216 	io_req_task_work_add(req);
217 	return HRTIMER_NORESTART;
218 }
219 
220 static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
221 					   struct io_cancel_data *cd)
222 	__must_hold(&ctx->timeout_lock)
223 {
224 	struct io_timeout *timeout;
225 	struct io_timeout_data *io;
226 	struct io_kiocb *req = NULL;
227 
228 	list_for_each_entry(timeout, &ctx->timeout_list, list) {
229 		struct io_kiocb *tmp = cmd_to_io_kiocb(timeout);
230 
231 		if (!(cd->flags & IORING_ASYNC_CANCEL_ANY) &&
232 		    cd->data != tmp->cqe.user_data)
233 			continue;
234 		if (cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY)) {
235 			if (cd->seq == tmp->work.cancel_seq)
236 				continue;
237 			tmp->work.cancel_seq = cd->seq;
238 		}
239 		req = tmp;
240 		break;
241 	}
242 	if (!req)
243 		return ERR_PTR(-ENOENT);
244 
245 	io = req->async_data;
246 	if (hrtimer_try_to_cancel(&io->timer) == -1)
247 		return ERR_PTR(-EALREADY);
248 	timeout = io_kiocb_to_cmd(req, struct io_timeout);
249 	list_del_init(&timeout->list);
250 	return req;
251 }
252 
253 int io_timeout_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
254 	__must_hold(&ctx->completion_lock)
255 {
256 	struct io_kiocb *req;
257 
258 	spin_lock_irq(&ctx->timeout_lock);
259 	req = io_timeout_extract(ctx, cd);
260 	spin_unlock_irq(&ctx->timeout_lock);
261 
262 	if (IS_ERR(req))
263 		return PTR_ERR(req);
264 	io_req_task_queue_fail(req, -ECANCELED);
265 	return 0;
266 }
267 
268 static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked)
269 {
270 	unsigned issue_flags = *locked ? 0 : IO_URING_F_UNLOCKED;
271 	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
272 	struct io_kiocb *prev = timeout->prev;
273 	int ret = -ENOENT;
274 
275 	if (prev) {
276 		if (!(req->task->flags & PF_EXITING)) {
277 			struct io_cancel_data cd = {
278 				.ctx		= req->ctx,
279 				.data		= prev->cqe.user_data,
280 			};
281 
282 			ret = io_try_cancel(req->task->io_uring, &cd, issue_flags);
283 		}
284 		io_req_set_res(req, ret ?: -ETIME, 0);
285 		io_req_complete_post(req);
286 		io_put_req(prev);
287 	} else {
288 		io_req_set_res(req, -ETIME, 0);
289 		io_req_complete_post(req);
290 	}
291 }
292 
293 static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
294 {
295 	struct io_timeout_data *data = container_of(timer,
296 						struct io_timeout_data, timer);
297 	struct io_kiocb *prev, *req = data->req;
298 	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
299 	struct io_ring_ctx *ctx = req->ctx;
300 	unsigned long flags;
301 
302 	spin_lock_irqsave(&ctx->timeout_lock, flags);
303 	prev = timeout->head;
304 	timeout->head = NULL;
305 
306 	/*
307 	 * We don't expect the list to be empty, that will only happen if we
308 	 * race with the completion of the linked work.
309 	 */
310 	if (prev) {
311 		io_remove_next_linked(prev);
312 		if (!req_ref_inc_not_zero(prev))
313 			prev = NULL;
314 	}
315 	list_del(&timeout->list);
316 	timeout->prev = prev;
317 	spin_unlock_irqrestore(&ctx->timeout_lock, flags);
318 
319 	req->io_task_work.func = io_req_task_link_timeout;
320 	io_req_task_work_add(req);
321 	return HRTIMER_NORESTART;
322 }
323 
324 static clockid_t io_timeout_get_clock(struct io_timeout_data *data)
325 {
326 	switch (data->flags & IORING_TIMEOUT_CLOCK_MASK) {
327 	case IORING_TIMEOUT_BOOTTIME:
328 		return CLOCK_BOOTTIME;
329 	case IORING_TIMEOUT_REALTIME:
330 		return CLOCK_REALTIME;
331 	default:
332 		/* can't happen, vetted at prep time */
333 		WARN_ON_ONCE(1);
334 		fallthrough;
335 	case 0:
336 		return CLOCK_MONOTONIC;
337 	}
338 }
339 
340 static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
341 				    struct timespec64 *ts, enum hrtimer_mode mode)
342 	__must_hold(&ctx->timeout_lock)
343 {
344 	struct io_timeout_data *io;
345 	struct io_timeout *timeout;
346 	struct io_kiocb *req = NULL;
347 
348 	list_for_each_entry(timeout, &ctx->ltimeout_list, list) {
349 		struct io_kiocb *tmp = cmd_to_io_kiocb(timeout);
350 
351 		if (user_data == tmp->cqe.user_data) {
352 			req = tmp;
353 			break;
354 		}
355 	}
356 	if (!req)
357 		return -ENOENT;
358 
359 	io = req->async_data;
360 	if (hrtimer_try_to_cancel(&io->timer) == -1)
361 		return -EALREADY;
362 	hrtimer_init(&io->timer, io_timeout_get_clock(io), mode);
363 	io->timer.function = io_link_timeout_fn;
364 	hrtimer_start(&io->timer, timespec64_to_ktime(*ts), mode);
365 	return 0;
366 }
367 
368 static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
369 			     struct timespec64 *ts, enum hrtimer_mode mode)
370 	__must_hold(&ctx->timeout_lock)
371 {
372 	struct io_cancel_data cd = { .data = user_data, };
373 	struct io_kiocb *req = io_timeout_extract(ctx, &cd);
374 	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
375 	struct io_timeout_data *data;
376 
377 	if (IS_ERR(req))
378 		return PTR_ERR(req);
379 
380 	timeout->off = 0; /* noseq */
381 	data = req->async_data;
382 	list_add_tail(&timeout->list, &ctx->timeout_list);
383 	hrtimer_init(&data->timer, io_timeout_get_clock(data), mode);
384 	data->timer.function = io_timeout_fn;
385 	hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
386 	return 0;
387 }
388 
389 int io_timeout_remove_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
390 {
391 	struct io_timeout_rem *tr = io_kiocb_to_cmd(req, struct io_timeout_rem);
392 
393 	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
394 		return -EINVAL;
395 	if (sqe->buf_index || sqe->len || sqe->splice_fd_in)
396 		return -EINVAL;
397 
398 	tr->ltimeout = false;
399 	tr->addr = READ_ONCE(sqe->addr);
400 	tr->flags = READ_ONCE(sqe->timeout_flags);
401 	if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) {
402 		if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
403 			return -EINVAL;
404 		if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
405 			tr->ltimeout = true;
406 		if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK|IORING_TIMEOUT_ABS))
407 			return -EINVAL;
408 		if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
409 			return -EFAULT;
410 		if (tr->ts.tv_sec < 0 || tr->ts.tv_nsec < 0)
411 			return -EINVAL;
412 	} else if (tr->flags) {
413 		/* timeout removal doesn't support flags */
414 		return -EINVAL;
415 	}
416 
417 	return 0;
418 }
419 
420 static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
421 {
422 	return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
423 					    : HRTIMER_MODE_REL;
424 }
425 
426 /*
427  * Remove or update an existing timeout command
428  */
429 int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
430 {
431 	struct io_timeout_rem *tr = io_kiocb_to_cmd(req, struct io_timeout_rem);
432 	struct io_ring_ctx *ctx = req->ctx;
433 	int ret;
434 
435 	if (!(tr->flags & IORING_TIMEOUT_UPDATE)) {
436 		struct io_cancel_data cd = { .data = tr->addr, };
437 
438 		spin_lock(&ctx->completion_lock);
439 		ret = io_timeout_cancel(ctx, &cd);
440 		spin_unlock(&ctx->completion_lock);
441 	} else {
442 		enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags);
443 
444 		spin_lock_irq(&ctx->timeout_lock);
445 		if (tr->ltimeout)
446 			ret = io_linked_timeout_update(ctx, tr->addr, &tr->ts, mode);
447 		else
448 			ret = io_timeout_update(ctx, tr->addr, &tr->ts, mode);
449 		spin_unlock_irq(&ctx->timeout_lock);
450 	}
451 
452 	if (ret < 0)
453 		req_set_fail(req);
454 	io_req_set_res(req, ret, 0);
455 	return IOU_OK;
456 }
457 
458 static int __io_timeout_prep(struct io_kiocb *req,
459 			     const struct io_uring_sqe *sqe,
460 			     bool is_timeout_link)
461 {
462 	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
463 	struct io_timeout_data *data;
464 	unsigned flags;
465 	u32 off = READ_ONCE(sqe->off);
466 
467 	if (sqe->buf_index || sqe->len != 1 || sqe->splice_fd_in)
468 		return -EINVAL;
469 	if (off && is_timeout_link)
470 		return -EINVAL;
471 	flags = READ_ONCE(sqe->timeout_flags);
472 	if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK |
473 		      IORING_TIMEOUT_ETIME_SUCCESS))
474 		return -EINVAL;
475 	/* more than one clock specified is invalid, obviously */
476 	if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
477 		return -EINVAL;
478 
479 	INIT_LIST_HEAD(&timeout->list);
480 	timeout->off = off;
481 	if (unlikely(off && !req->ctx->off_timeout_used))
482 		req->ctx->off_timeout_used = true;
483 
484 	if (WARN_ON_ONCE(req_has_async_data(req)))
485 		return -EFAULT;
486 	if (io_alloc_async_data(req))
487 		return -ENOMEM;
488 
489 	data = req->async_data;
490 	data->req = req;
491 	data->flags = flags;
492 
493 	if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
494 		return -EFAULT;
495 
496 	if (data->ts.tv_sec < 0 || data->ts.tv_nsec < 0)
497 		return -EINVAL;
498 
499 	INIT_LIST_HEAD(&timeout->list);
500 	data->mode = io_translate_timeout_mode(flags);
501 	hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode);
502 
503 	if (is_timeout_link) {
504 		struct io_submit_link *link = &req->ctx->submit_state.link;
505 
506 		if (!link->head)
507 			return -EINVAL;
508 		if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
509 			return -EINVAL;
510 		timeout->head = link->last;
511 		link->last->flags |= REQ_F_ARM_LTIMEOUT;
512 	}
513 	return 0;
514 }
515 
516 int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
517 {
518 	return __io_timeout_prep(req, sqe, false);
519 }
520 
521 int io_link_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
522 {
523 	return __io_timeout_prep(req, sqe, true);
524 }
525 
526 int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
527 {
528 	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
529 	struct io_ring_ctx *ctx = req->ctx;
530 	struct io_timeout_data *data = req->async_data;
531 	struct list_head *entry;
532 	u32 tail, off = timeout->off;
533 
534 	spin_lock_irq(&ctx->timeout_lock);
535 
536 	/*
537 	 * sqe->off holds how many events that need to occur for this
538 	 * timeout event to be satisfied. If it isn't set, then this is
539 	 * a pure timeout request, sequence isn't used.
540 	 */
541 	if (io_is_timeout_noseq(req)) {
542 		entry = ctx->timeout_list.prev;
543 		goto add;
544 	}
545 
546 	tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
547 	timeout->target_seq = tail + off;
548 
549 	/* Update the last seq here in case io_flush_timeouts() hasn't.
550 	 * This is safe because ->completion_lock is held, and submissions
551 	 * and completions are never mixed in the same ->completion_lock section.
552 	 */
553 	ctx->cq_last_tm_flush = tail;
554 
555 	/*
556 	 * Insertion sort, ensuring the first entry in the list is always
557 	 * the one we need first.
558 	 */
559 	list_for_each_prev(entry, &ctx->timeout_list) {
560 		struct io_timeout *nextt = list_entry(entry, struct io_timeout, list);
561 		struct io_kiocb *nxt = cmd_to_io_kiocb(nextt);
562 
563 		if (io_is_timeout_noseq(nxt))
564 			continue;
565 		/* nxt.seq is behind @tail, otherwise would've been completed */
566 		if (off >= nextt->target_seq - tail)
567 			break;
568 	}
569 add:
570 	list_add(&timeout->list, entry);
571 	data->timer.function = io_timeout_fn;
572 	hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
573 	spin_unlock_irq(&ctx->timeout_lock);
574 	return IOU_ISSUE_SKIP_COMPLETE;
575 }
576 
577 void io_queue_linked_timeout(struct io_kiocb *req)
578 {
579 	struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
580 	struct io_ring_ctx *ctx = req->ctx;
581 
582 	spin_lock_irq(&ctx->timeout_lock);
583 	/*
584 	 * If the back reference is NULL, then our linked request finished
585 	 * before we got a chance to setup the timer
586 	 */
587 	if (timeout->head) {
588 		struct io_timeout_data *data = req->async_data;
589 
590 		data->timer.function = io_link_timeout_fn;
591 		hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
592 				data->mode);
593 		list_add_tail(&timeout->list, &ctx->ltimeout_list);
594 	}
595 	spin_unlock_irq(&ctx->timeout_lock);
596 	/* drop submission reference */
597 	io_put_req(req);
598 }
599 
600 static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
601 			  bool cancel_all)
602 	__must_hold(&req->ctx->timeout_lock)
603 {
604 	struct io_kiocb *req;
605 
606 	if (task && head->task != task)
607 		return false;
608 	if (cancel_all)
609 		return true;
610 
611 	io_for_each_link(req, head) {
612 		if (req->flags & REQ_F_INFLIGHT)
613 			return true;
614 	}
615 	return false;
616 }
617 
618 /* Returns true if we found and killed one or more timeouts */
619 __cold bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
620 			     bool cancel_all)
621 {
622 	struct io_timeout *timeout, *tmp;
623 	int canceled = 0;
624 
625 	io_cq_lock(ctx);
626 	spin_lock_irq(&ctx->timeout_lock);
627 	list_for_each_entry_safe(timeout, tmp, &ctx->timeout_list, list) {
628 		struct io_kiocb *req = cmd_to_io_kiocb(timeout);
629 
630 		if (io_match_task(req, tsk, cancel_all) &&
631 		    io_kill_timeout(req, -ECANCELED))
632 			canceled++;
633 	}
634 	spin_unlock_irq(&ctx->timeout_lock);
635 	io_cq_unlock_post(ctx);
636 	return canceled != 0;
637 }
638