projects/linux·blob master · refs

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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#include <linux/time_namespace.h>
7
8#include <trace/events/io_uring.h>
9
10#include <uapi/linux/io_uring.h>
11
12#include "io_uring.h"
13#include "refs.h"
14#include "cancel.h"
15#include "timeout.h"
16
17struct io_timeout {
18 struct file *file;
19 u32 off;
20 u32 target_seq;
21 u32 repeats;
22 struct list_head list;
23 /* head of the link, used by linked timeouts only */
24 struct io_kiocb *head;
25 /* for linked completions */
26 struct io_kiocb *prev;
27};
28
29struct io_timeout_rem {
30 struct file *file;
31 u64 addr;
32
33 /* timeout update */
34 ktime_t time;
35 u32 flags;
36 bool ltimeout;
37};
38
39static clockid_t io_flags_to_clock(unsigned flags)
40{
41 switch (flags & IORING_TIMEOUT_CLOCK_MASK) {
42 case IORING_TIMEOUT_BOOTTIME:
43 return CLOCK_BOOTTIME;
44 case IORING_TIMEOUT_REALTIME:
45 return CLOCK_REALTIME;
46 default:
47 /* can't happen, vetted at prep time */
48 WARN_ON_ONCE(1);
49 fallthrough;
50 case 0:
51 return CLOCK_MONOTONIC;
52 }
53}
54
55static int io_parse_user_time(ktime_t *time, u64 arg, unsigned flags)
56{
57 struct timespec64 ts;
58
59 if (flags & IORING_TIMEOUT_IMMEDIATE_ARG) {
60 *time = ns_to_ktime(arg);
61 if (*time < 0)
62 return -EINVAL;
63 goto out;
64 }
65
66 if (get_timespec64(&ts, u64_to_user_ptr(arg)))
67 return -EFAULT;
68 if (ts.tv_sec < 0 || ts.tv_nsec < 0)
69 return -EINVAL;
70 *time = timespec64_to_ktime(ts);
71out:
72 if (flags & IORING_TIMEOUT_ABS)
73 *time = timens_ktime_to_host(io_flags_to_clock(flags), *time);
74 return 0;
75}
76
77static struct io_kiocb *__io_disarm_linked_timeout(struct io_kiocb *req,
78 struct io_kiocb *link);
79
80static inline bool io_is_timeout_noseq(struct io_kiocb *req)
81{
82 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
83 struct io_timeout_data *data = req->async_data;
84
85 return !timeout->off || data->flags & IORING_TIMEOUT_MULTISHOT;
86}
87
88static inline void io_put_req(struct io_kiocb *req)
89{
90 if (req_ref_put_and_test(req)) {
91 io_queue_next(req);
92 io_free_req(req);
93 }
94}
95
96static inline bool io_timeout_finish(struct io_timeout *timeout,
97 struct io_timeout_data *data)
98{
99 if (!(data->flags & IORING_TIMEOUT_MULTISHOT))
100 return true;
101
102 if (!timeout->off || (timeout->repeats && --timeout->repeats))
103 return false;
104
105 return true;
106}
107
108static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer);
109
110static void io_timeout_complete(struct io_tw_req tw_req, io_tw_token_t tw)
111{
112 struct io_kiocb *req = tw_req.req;
113 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
114 struct io_timeout_data *data = req->async_data;
115 struct io_ring_ctx *ctx = req->ctx;
116
117 if (!io_timeout_finish(timeout, data)) {
118 if (io_req_post_cqe(req, -ETIME, IORING_CQE_F_MORE)) {
119 /* re-arm timer */
120 raw_spin_lock_irq(&ctx->timeout_lock);
121 list_add(&timeout->list, ctx->timeout_list.prev);
122 hrtimer_start(&data->timer, data->time, data->mode);
123 raw_spin_unlock_irq(&ctx->timeout_lock);
124 return;
125 }
126 }
127
128 io_req_task_complete(tw_req, tw);
129}
130
131static __cold bool io_flush_killed_timeouts(struct list_head *list, int err)
132{
133 if (list_empty(list))
134 return false;
135
136 while (!list_empty(list)) {
137 struct io_timeout *timeout;
138 struct io_kiocb *req;
139
140 timeout = list_first_entry(list, struct io_timeout, list);
141 list_del_init(&timeout->list);
142 req = cmd_to_io_kiocb(timeout);
143 if (err)
144 req_set_fail(req);
145 io_req_queue_tw_complete(req, err);
146 }
147
148 return true;
149}
150
151static void io_kill_timeout(struct io_kiocb *req, struct list_head *list)
152 __must_hold(&req->ctx->timeout_lock)
153{
154 struct io_timeout_data *io = req->async_data;
155
156 if (hrtimer_try_to_cancel(&io->timer) != -1) {
157 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
158
159 atomic_set(&req->ctx->cq_timeouts,
160 atomic_read(&req->ctx->cq_timeouts) + 1);
161 list_move_tail(&timeout->list, list);
162 }
163}
164
165__cold void io_flush_timeouts(struct io_ring_ctx *ctx)
166{
167 struct io_timeout *timeout, *tmp;
168 LIST_HEAD(list);
169 u32 seq;
170
171 raw_spin_lock_irq(&ctx->timeout_lock);
172 seq = READ_ONCE(ctx->cached_cq_tail) - atomic_read(&ctx->cq_timeouts);
173
174 list_for_each_entry_safe(timeout, tmp, &ctx->timeout_list, list) {
175 struct io_kiocb *req = cmd_to_io_kiocb(timeout);
176 u32 events_needed, events_got;
177
178 if (io_is_timeout_noseq(req))
179 break;
180
181 /*
182 * Since seq can easily wrap around over time, subtract
183 * the last seq at which timeouts were flushed before comparing.
184 * Assuming not more than 2^31-1 events have happened since,
185 * these subtractions won't have wrapped, so we can check if
186 * target is in [last_seq, current_seq] by comparing the two.
187 */
188 events_needed = timeout->target_seq - ctx->cq_last_tm_flush;
189 events_got = seq - ctx->cq_last_tm_flush;
190 if (events_got < events_needed)
191 break;
192
193 io_kill_timeout(req, &list);
194 }
195 ctx->cq_last_tm_flush = seq;
196 raw_spin_unlock_irq(&ctx->timeout_lock);
197 io_flush_killed_timeouts(&list, 0);
198}
199
200static void io_req_tw_fail_links(struct io_tw_req tw_req, io_tw_token_t tw)
201{
202 struct io_kiocb *link = tw_req.req;
203
204 io_tw_lock(link->ctx, tw);
205 while (link) {
206 struct io_kiocb *nxt = link->link;
207 long res = -ECANCELED;
208
209 if (link->flags & REQ_F_FAIL)
210 res = link->cqe.res;
211 link->link = NULL;
212 io_req_set_res(link, res, 0);
213 io_req_task_complete((struct io_tw_req){link}, tw);
214 link = nxt;
215 }
216}
217
218static void io_fail_links(struct io_kiocb *req)
219 __must_hold(&req->ctx->completion_lock)
220{
221 struct io_kiocb *link = req->link;
222 bool ignore_cqes = req->flags & REQ_F_SKIP_LINK_CQES;
223
224 if (!link)
225 return;
226
227 while (link) {
228 if (ignore_cqes)
229 link->flags |= REQ_F_CQE_SKIP;
230 else
231 link->flags &= ~REQ_F_CQE_SKIP;
232 trace_io_uring_fail_link(req, link);
233 link = link->link;
234 }
235
236 link = req->link;
237 link->io_task_work.func = io_req_tw_fail_links;
238 io_req_task_work_add(link);
239 req->link = NULL;
240}
241
242static inline void io_remove_next_linked(struct io_kiocb *req)
243{
244 struct io_kiocb *nxt = req->link;
245
246 req->link = nxt->link;
247 nxt->link = NULL;
248}
249
250void io_disarm_next(struct io_kiocb *req)
251 __must_hold(&req->ctx->completion_lock)
252{
253 struct io_kiocb *link = NULL;
254
255 if (req->flags & REQ_F_ARM_LTIMEOUT) {
256 link = req->link;
257 req->flags &= ~REQ_F_ARM_LTIMEOUT;
258 if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
259 io_remove_next_linked(req);
260 io_req_queue_tw_complete(link, -ECANCELED);
261 }
262 } else if (req->flags & REQ_F_LINK_TIMEOUT) {
263 struct io_ring_ctx *ctx = req->ctx;
264
265 raw_spin_lock_irq(&ctx->timeout_lock);
266 if (req->link && req->link->opcode == IORING_OP_LINK_TIMEOUT)
267 link = __io_disarm_linked_timeout(req, req->link);
268
269 raw_spin_unlock_irq(&ctx->timeout_lock);
270 if (link)
271 io_req_queue_tw_complete(link, -ECANCELED);
272 }
273 if (unlikely((req->flags & REQ_F_FAIL) &&
274 !(req->flags & REQ_F_HARDLINK)))
275 io_fail_links(req);
276}
277
278static struct io_kiocb *__io_disarm_linked_timeout(struct io_kiocb *req,
279 struct io_kiocb *link)
280 __must_hold(&req->ctx->completion_lock)
281 __must_hold(&req->ctx->timeout_lock)
282{
283 struct io_timeout_data *io = link->async_data;
284 struct io_timeout *timeout = io_kiocb_to_cmd(link, struct io_timeout);
285
286 io_remove_next_linked(req);
287
288 /* If this is NULL, then timer already claimed it and will complete it */
289 if (!timeout->head)
290 return NULL;
291 timeout->head = NULL;
292 if (hrtimer_try_to_cancel(&io->timer) != -1) {
293 list_del(&timeout->list);
294 return link;
295 }
296
297 return NULL;
298}
299
300static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
301{
302 struct io_timeout_data *data = container_of(timer,
303 struct io_timeout_data, timer);
304 struct io_kiocb *req = data->req;
305 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
306 struct io_ring_ctx *ctx = req->ctx;
307 unsigned long flags;
308
309 raw_spin_lock_irqsave(&ctx->timeout_lock, flags);
310 list_del_init(&timeout->list);
311 atomic_set(&ctx->cq_timeouts,
312 atomic_read(&ctx->cq_timeouts) + 1);
313 raw_spin_unlock_irqrestore(&ctx->timeout_lock, flags);
314
315 if (!(data->flags & IORING_TIMEOUT_ETIME_SUCCESS))
316 req_set_fail(req);
317
318 io_req_set_res(req, -ETIME, 0);
319 req->io_task_work.func = io_timeout_complete;
320 io_req_task_work_add(req);
321 return HRTIMER_NORESTART;
322}
323
324static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
325 struct io_cancel_data *cd)
326 __must_hold(&ctx->timeout_lock)
327{
328 struct io_timeout *timeout;
329 struct io_timeout_data *io;
330 struct io_kiocb *req = NULL;
331
332 list_for_each_entry(timeout, &ctx->timeout_list, list) {
333 struct io_kiocb *tmp = cmd_to_io_kiocb(timeout);
334
335 if (io_cancel_req_match(tmp, cd)) {
336 req = tmp;
337 break;
338 }
339 }
340 if (!req)
341 return ERR_PTR(-ENOENT);
342
343 io = req->async_data;
344 if (hrtimer_try_to_cancel(&io->timer) == -1)
345 return ERR_PTR(-EALREADY);
346 timeout = io_kiocb_to_cmd(req, struct io_timeout);
347 list_del_init(&timeout->list);
348 return req;
349}
350
351int io_timeout_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
352 __must_hold(&ctx->completion_lock)
353{
354 struct io_kiocb *req;
355
356 raw_spin_lock_irq(&ctx->timeout_lock);
357 req = io_timeout_extract(ctx, cd);
358 raw_spin_unlock_irq(&ctx->timeout_lock);
359
360 if (IS_ERR(req))
361 return PTR_ERR(req);
362 io_req_task_queue_fail(req, -ECANCELED);
363 return 0;
364}
365
366static void io_req_task_link_timeout(struct io_tw_req tw_req, io_tw_token_t tw)
367{
368 struct io_kiocb *req = tw_req.req;
369 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
370 struct io_kiocb *prev = timeout->prev;
371 int ret;
372
373 if (prev) {
374 /*
375 * splice the linked timeout out of prev's chain if the regular
376 * completion path didn't already do it.
377 */
378 if (prev->link == req)
379 prev->link = req->link;
380 req->link = NULL;
381
382 if (!tw.cancel) {
383 struct io_cancel_data cd = {
384 .ctx = req->ctx,
385 .data = prev->cqe.user_data,
386 };
387
388 ret = io_try_cancel(req->tctx, &cd, 0);
389 } else {
390 ret = -ECANCELED;
391 }
392 io_req_set_res(req, ret ?: -ETIME, 0);
393 io_req_task_complete(tw_req, tw);
394 io_put_req(prev);
395 } else {
396 io_req_set_res(req, -ETIME, 0);
397 io_req_task_complete(tw_req, tw);
398 }
399}
400
401static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
402{
403 struct io_timeout_data *data = container_of(timer,
404 struct io_timeout_data, timer);
405 struct io_kiocb *prev, *req = data->req;
406 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
407 struct io_ring_ctx *ctx = req->ctx;
408 unsigned long flags;
409
410 raw_spin_lock_irqsave(&ctx->timeout_lock, flags);
411 prev = timeout->head;
412 timeout->head = NULL;
413
414 /*
415 * We don't expect the list to be empty, that will only happen if we
416 * race with the completion of the linked work. Splice of prev is
417 * done in io_req_task_link_timeout(), if needed.
418 */
419 if (prev) {
420 if (!req_ref_inc_not_zero(prev)) {
421 io_remove_next_linked(prev);
422 prev = NULL;
423 }
424 }
425 list_del(&timeout->list);
426 timeout->prev = prev;
427 raw_spin_unlock_irqrestore(&ctx->timeout_lock, flags);
428
429 req->io_task_work.func = io_req_task_link_timeout;
430 io_req_task_work_add(req);
431 return HRTIMER_NORESTART;
432}
433
434static clockid_t io_timeout_get_clock(struct io_timeout_data *data)
435{
436 return io_flags_to_clock(data->flags);
437}
438
439static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
440 ktime_t ts, enum hrtimer_mode mode)
441 __must_hold(&ctx->timeout_lock)
442{
443 struct io_timeout_data *io;
444 struct io_timeout *timeout;
445 struct io_kiocb *req = NULL;
446
447 list_for_each_entry(timeout, &ctx->ltimeout_list, list) {
448 struct io_kiocb *tmp = cmd_to_io_kiocb(timeout);
449
450 if (user_data == tmp->cqe.user_data) {
451 req = tmp;
452 break;
453 }
454 }
455 if (!req)
456 return -ENOENT;
457
458 io = req->async_data;
459 if (hrtimer_try_to_cancel(&io->timer) == -1)
460 return -EALREADY;
461 hrtimer_setup(&io->timer, io_link_timeout_fn, io_timeout_get_clock(io), mode);
462 hrtimer_start(&io->timer, ts, mode);
463 return 0;
464}
465
466static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
467 ktime_t time, enum hrtimer_mode mode)
468 __must_hold(&ctx->timeout_lock)
469{
470 struct io_cancel_data cd = { .ctx = ctx, .data = user_data, };
471 struct io_kiocb *req = io_timeout_extract(ctx, &cd);
472 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
473 struct io_timeout_data *data;
474
475 if (IS_ERR(req))
476 return PTR_ERR(req);
477
478 timeout->off = 0; /* noseq */
479 data = req->async_data;
480 data->time = time;
481
482 list_add_tail(&timeout->list, &ctx->timeout_list);
483 hrtimer_setup(&data->timer, io_timeout_fn, io_timeout_get_clock(data), mode);
484 hrtimer_start(&data->timer, data->time, mode);
485 return 0;
486}
487
488int io_timeout_remove_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
489{
490 struct io_timeout_rem *tr = io_kiocb_to_cmd(req, struct io_timeout_rem);
491 int ret;
492
493 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
494 return -EINVAL;
495 if (sqe->addr3 || sqe->__pad2[0])
496 return -EINVAL;
497 if (sqe->buf_index || sqe->len || sqe->splice_fd_in)
498 return -EINVAL;
499
500 tr->ltimeout = false;
501 tr->addr = READ_ONCE(sqe->addr);
502 tr->flags = READ_ONCE(sqe->timeout_flags);
503 if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) {
504 if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
505 return -EINVAL;
506 if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
507 tr->ltimeout = true;
508 if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK |
509 IORING_TIMEOUT_ABS |
510 IORING_TIMEOUT_IMMEDIATE_ARG))
511 return -EINVAL;
512 ret = io_parse_user_time(&tr->time, READ_ONCE(sqe->addr2), tr->flags);
513 if (ret)
514 return ret;
515 } else if (tr->flags) {
516 /* timeout removal doesn't support flags */
517 return -EINVAL;
518 }
519
520 return 0;
521}
522
523static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
524{
525 return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
526 : HRTIMER_MODE_REL;
527}
528
529/*
530 * Remove or update an existing timeout command
531 */
532int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
533{
534 struct io_timeout_rem *tr = io_kiocb_to_cmd(req, struct io_timeout_rem);
535 struct io_ring_ctx *ctx = req->ctx;
536 int ret;
537
538 if (!(tr->flags & IORING_TIMEOUT_UPDATE)) {
539 struct io_cancel_data cd = { .ctx = ctx, .data = tr->addr, };
540
541 spin_lock(&ctx->completion_lock);
542 ret = io_timeout_cancel(ctx, &cd);
543 spin_unlock(&ctx->completion_lock);
544 } else {
545 enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags);
546
547 raw_spin_lock_irq(&ctx->timeout_lock);
548 if (tr->ltimeout)
549 ret = io_linked_timeout_update(ctx, tr->addr, tr->time, mode);
550 else
551 ret = io_timeout_update(ctx, tr->addr, tr->time, mode);
552 raw_spin_unlock_irq(&ctx->timeout_lock);
553 }
554
555 if (ret < 0)
556 req_set_fail(req);
557 io_req_set_res(req, ret, 0);
558 return IOU_COMPLETE;
559}
560
561static int __io_timeout_prep(struct io_kiocb *req,
562 const struct io_uring_sqe *sqe,
563 bool is_timeout_link)
564{
565 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
566 struct io_timeout_data *data;
567 unsigned flags;
568 u32 off = READ_ONCE(sqe->off);
569 int ret;
570
571 if (sqe->addr3 || sqe->__pad2[0])
572 return -EINVAL;
573 if (sqe->buf_index || sqe->len != 1 || sqe->splice_fd_in)
574 return -EINVAL;
575 if (off && is_timeout_link)
576 return -EINVAL;
577 flags = READ_ONCE(sqe->timeout_flags);
578 if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK |
579 IORING_TIMEOUT_ETIME_SUCCESS |
580 IORING_TIMEOUT_MULTISHOT |
581 IORING_TIMEOUT_IMMEDIATE_ARG))
582 return -EINVAL;
583 /* more than one clock specified is invalid, obviously */
584 if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
585 return -EINVAL;
586 /* multishot requests only make sense with rel values */
587 if (!(~flags & (IORING_TIMEOUT_MULTISHOT | IORING_TIMEOUT_ABS)))
588 return -EINVAL;
589
590 INIT_LIST_HEAD(&timeout->list);
591 timeout->off = off;
592 if (unlikely(off && !(req->ctx->int_flags & IO_RING_F_OFF_TIMEOUT_USED)))
593 req->ctx->int_flags |= IO_RING_F_OFF_TIMEOUT_USED;
594 /*
595 * for multishot reqs w/ fixed nr of repeats, repeats tracks the
596 * remaining nr
597 */
598 timeout->repeats = 0;
599 if ((flags & IORING_TIMEOUT_MULTISHOT) && off > 0)
600 timeout->repeats = off;
601
602 if (WARN_ON_ONCE(req_has_async_data(req)))
603 return -EFAULT;
604 data = io_uring_alloc_async_data(NULL, req);
605 if (!data)
606 return -ENOMEM;
607 data->req = req;
608 data->flags = flags;
609
610 ret = io_parse_user_time(&data->time, READ_ONCE(sqe->addr), flags);
611 if (ret)
612 return ret;
613
614 data->mode = io_translate_timeout_mode(flags);
615
616 if (is_timeout_link) {
617 struct io_submit_link *link = &req->ctx->submit_state.link;
618
619 if (!link->head)
620 return -EINVAL;
621 if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
622 return -EINVAL;
623 timeout->head = link->last;
624 link->last->flags |= REQ_F_ARM_LTIMEOUT;
625 hrtimer_setup(&data->timer, io_link_timeout_fn, io_timeout_get_clock(data),
626 data->mode);
627 } else {
628 hrtimer_setup(&data->timer, io_timeout_fn, io_timeout_get_clock(data), data->mode);
629 }
630 return 0;
631}
632
633int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
634{
635 return __io_timeout_prep(req, sqe, false);
636}
637
638int io_link_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
639{
640 return __io_timeout_prep(req, sqe, true);
641}
642
643int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
644{
645 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
646 struct io_ring_ctx *ctx = req->ctx;
647 struct io_timeout_data *data = req->async_data;
648 struct list_head *entry;
649 u32 tail, off = timeout->off;
650
651 raw_spin_lock_irq(&ctx->timeout_lock);
652
653 /*
654 * sqe->off holds how many events that need to occur for this
655 * timeout event to be satisfied. If it isn't set, then this is
656 * a pure timeout request, sequence isn't used.
657 */
658 if (io_is_timeout_noseq(req)) {
659 entry = ctx->timeout_list.prev;
660 goto add;
661 }
662
663 tail = data_race(ctx->cached_cq_tail) - atomic_read(&ctx->cq_timeouts);
664 timeout->target_seq = tail + off;
665
666 /* Update the last seq here in case io_flush_timeouts() hasn't.
667 * This is safe because ->completion_lock is held, and submissions
668 * and completions are never mixed in the same ->completion_lock section.
669 */
670 ctx->cq_last_tm_flush = tail;
671
672 /*
673 * Insertion sort, ensuring the first entry in the list is always
674 * the one we need first.
675 */
676 list_for_each_prev(entry, &ctx->timeout_list) {
677 struct io_timeout *nextt = list_entry(entry, struct io_timeout, list);
678 struct io_kiocb *nxt = cmd_to_io_kiocb(nextt);
679
680 if (io_is_timeout_noseq(nxt))
681 continue;
682 /* nxt.seq is behind @tail, otherwise would've been completed */
683 if (off >= nextt->target_seq - tail)
684 break;
685 }
686add:
687 list_add(&timeout->list, entry);
688 hrtimer_start(&data->timer, data->time, data->mode);
689 raw_spin_unlock_irq(&ctx->timeout_lock);
690 return IOU_ISSUE_SKIP_COMPLETE;
691}
692
693void io_queue_linked_timeout(struct io_kiocb *req)
694{
695 struct io_timeout *timeout = io_kiocb_to_cmd(req, struct io_timeout);
696 struct io_ring_ctx *ctx = req->ctx;
697
698 raw_spin_lock_irq(&ctx->timeout_lock);
699 /*
700 * If the back reference is NULL, then our linked request finished
701 * before we got a chance to setup the timer
702 */
703 if (timeout->head) {
704 struct io_timeout_data *data = req->async_data;
705
706 hrtimer_start(&data->timer, data->time, data->mode);
707 list_add_tail(&timeout->list, &ctx->ltimeout_list);
708 }
709 raw_spin_unlock_irq(&ctx->timeout_lock);
710 /* drop submission reference */
711 io_put_req(req);
712}
713
714static bool io_match_task(struct io_kiocb *head, struct io_uring_task *tctx,
715 bool cancel_all)
716 __must_hold(&head->ctx->timeout_lock)
717{
718 struct io_kiocb *req;
719
720 if (tctx && head->tctx != tctx)
721 return false;
722 if (cancel_all)
723 return true;
724
725 io_for_each_link(req, head) {
726 if (req->flags & REQ_F_INFLIGHT)
727 return true;
728 }
729 return false;
730}
731
732/* Returns true if we found and killed one or more timeouts */
733__cold bool io_kill_timeouts(struct io_ring_ctx *ctx, struct io_uring_task *tctx,
734 bool cancel_all)
735{
736 struct io_timeout *timeout, *tmp;
737 LIST_HEAD(list);
738
739 /*
740 * completion_lock is needed for io_match_task(). Take it before
741 * timeout_lockfirst to keep locking ordering.
742 */
743 spin_lock(&ctx->completion_lock);
744 raw_spin_lock_irq(&ctx->timeout_lock);
745 list_for_each_entry_safe(timeout, tmp, &ctx->timeout_list, list) {
746 struct io_kiocb *req = cmd_to_io_kiocb(timeout);
747
748 if (io_match_task(req, tctx, cancel_all))
749 io_kill_timeout(req, &list);
750 }
751 raw_spin_unlock_irq(&ctx->timeout_lock);
752 spin_unlock(&ctx->completion_lock);
753
754 return io_flush_killed_timeouts(&list, -ECANCELED);
755}