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2b188cc1
JA
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Shared application/kernel submission and completion ring pairs, for
4 * supporting fast/efficient IO.
5 *
6 * A note on the read/write ordering memory barriers that are matched between
1e84b97b
SB
7 * the application and kernel side.
8 *
9 * After the application reads the CQ ring tail, it must use an
10 * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
11 * before writing the tail (using smp_load_acquire to read the tail will
12 * do). It also needs a smp_mb() before updating CQ head (ordering the
13 * entry load(s) with the head store), pairing with an implicit barrier
14 * through a control-dependency in io_get_cqring (smp_store_release to
15 * store head will do). Failure to do so could lead to reading invalid
16 * CQ entries.
17 *
18 * Likewise, the application must use an appropriate smp_wmb() before
19 * writing the SQ tail (ordering SQ entry stores with the tail store),
20 * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
21 * to store the tail will do). And it needs a barrier ordering the SQ
22 * head load before writing new SQ entries (smp_load_acquire to read
23 * head will do).
24 *
25 * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
26 * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
27 * updating the SQ tail; a full memory barrier smp_mb() is needed
28 * between.
2b188cc1
JA
29 *
30 * Also see the examples in the liburing library:
31 *
32 * git://git.kernel.dk/liburing
33 *
34 * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
35 * from data shared between the kernel and application. This is done both
36 * for ordering purposes, but also to ensure that once a value is loaded from
37 * data that the application could potentially modify, it remains stable.
38 *
39 * Copyright (C) 2018-2019 Jens Axboe
c992fe29 40 * Copyright (c) 2018-2019 Christoph Hellwig
2b188cc1
JA
41 */
42#include <linux/kernel.h>
43#include <linux/init.h>
44#include <linux/errno.h>
45#include <linux/syscalls.h>
46#include <linux/compat.h>
52de1fe1 47#include <net/compat.h>
2b188cc1
JA
48#include <linux/refcount.h>
49#include <linux/uio.h>
6b47ee6e 50#include <linux/bits.h>
2b188cc1
JA
51
52#include <linux/sched/signal.h>
53#include <linux/fs.h>
54#include <linux/file.h>
55#include <linux/fdtable.h>
56#include <linux/mm.h>
57#include <linux/mman.h>
2b188cc1
JA
58#include <linux/percpu.h>
59#include <linux/slab.h>
2b188cc1 60#include <linux/blkdev.h>
edafccee 61#include <linux/bvec.h>
2b188cc1
JA
62#include <linux/net.h>
63#include <net/sock.h>
64#include <net/af_unix.h>
6b06314c 65#include <net/scm.h>
2b188cc1
JA
66#include <linux/anon_inodes.h>
67#include <linux/sched/mm.h>
68#include <linux/uaccess.h>
69#include <linux/nospec.h>
edafccee
JA
70#include <linux/sizes.h>
71#include <linux/hugetlb.h>
aa4c3967 72#include <linux/highmem.h>
15b71abe
JA
73#include <linux/namei.h>
74#include <linux/fsnotify.h>
4840e418 75#include <linux/fadvise.h>
3e4827b0 76#include <linux/eventpoll.h>
7d67af2c 77#include <linux/splice.h>
b41e9852 78#include <linux/task_work.h>
bcf5a063 79#include <linux/pagemap.h>
0f212204 80#include <linux/io_uring.h>
2b188cc1 81
c826bd7a
DD
82#define CREATE_TRACE_POINTS
83#include <trace/events/io_uring.h>
84
2b188cc1
JA
85#include <uapi/linux/io_uring.h>
86
87#include "internal.h"
561fb04a 88#include "io-wq.h"
2b188cc1 89
5277deaa 90#define IORING_MAX_ENTRIES 32768
33a107f0 91#define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
65e19f54
JA
92
93/*
94 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
95 */
96#define IORING_FILE_TABLE_SHIFT 9
97#define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
98#define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
99#define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
21b55dbc
SG
100#define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
101 IORING_REGISTER_LAST + IORING_OP_LAST)
2b188cc1 102
b16fed66
PB
103#define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
104 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
105 IOSQE_BUFFER_SELECT)
106
2b188cc1
JA
107struct io_uring {
108 u32 head ____cacheline_aligned_in_smp;
109 u32 tail ____cacheline_aligned_in_smp;
110};
111
1e84b97b 112/*
75b28aff
HV
113 * This data is shared with the application through the mmap at offsets
114 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
1e84b97b
SB
115 *
116 * The offsets to the member fields are published through struct
117 * io_sqring_offsets when calling io_uring_setup.
118 */
75b28aff 119struct io_rings {
1e84b97b
SB
120 /*
121 * Head and tail offsets into the ring; the offsets need to be
122 * masked to get valid indices.
123 *
75b28aff
HV
124 * The kernel controls head of the sq ring and the tail of the cq ring,
125 * and the application controls tail of the sq ring and the head of the
126 * cq ring.
1e84b97b 127 */
75b28aff 128 struct io_uring sq, cq;
1e84b97b 129 /*
75b28aff 130 * Bitmasks to apply to head and tail offsets (constant, equals
1e84b97b
SB
131 * ring_entries - 1)
132 */
75b28aff
HV
133 u32 sq_ring_mask, cq_ring_mask;
134 /* Ring sizes (constant, power of 2) */
135 u32 sq_ring_entries, cq_ring_entries;
1e84b97b
SB
136 /*
137 * Number of invalid entries dropped by the kernel due to
138 * invalid index stored in array
139 *
140 * Written by the kernel, shouldn't be modified by the
141 * application (i.e. get number of "new events" by comparing to
142 * cached value).
143 *
144 * After a new SQ head value was read by the application this
145 * counter includes all submissions that were dropped reaching
146 * the new SQ head (and possibly more).
147 */
75b28aff 148 u32 sq_dropped;
1e84b97b 149 /*
0d9b5b3a 150 * Runtime SQ flags
1e84b97b
SB
151 *
152 * Written by the kernel, shouldn't be modified by the
153 * application.
154 *
155 * The application needs a full memory barrier before checking
156 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
157 */
75b28aff 158 u32 sq_flags;
0d9b5b3a
SG
159 /*
160 * Runtime CQ flags
161 *
162 * Written by the application, shouldn't be modified by the
163 * kernel.
164 */
165 u32 cq_flags;
1e84b97b
SB
166 /*
167 * Number of completion events lost because the queue was full;
168 * this should be avoided by the application by making sure
0b4295b5 169 * there are not more requests pending than there is space in
1e84b97b
SB
170 * the completion queue.
171 *
172 * Written by the kernel, shouldn't be modified by the
173 * application (i.e. get number of "new events" by comparing to
174 * cached value).
175 *
176 * As completion events come in out of order this counter is not
177 * ordered with any other data.
178 */
75b28aff 179 u32 cq_overflow;
1e84b97b
SB
180 /*
181 * Ring buffer of completion events.
182 *
183 * The kernel writes completion events fresh every time they are
184 * produced, so the application is allowed to modify pending
185 * entries.
186 */
75b28aff 187 struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp;
2b188cc1
JA
188};
189
45d189c6
PB
190enum io_uring_cmd_flags {
191 IO_URING_F_NONBLOCK = 1,
889fca73 192 IO_URING_F_COMPLETE_DEFER = 2,
45d189c6
PB
193};
194
edafccee
JA
195struct io_mapped_ubuf {
196 u64 ubuf;
197 size_t len;
198 struct bio_vec *bvec;
199 unsigned int nr_bvecs;
de293938 200 unsigned long acct_pages;
edafccee
JA
201};
202
50238531
BM
203struct io_ring_ctx;
204
6c2450ae
PB
205struct io_overflow_cqe {
206 struct io_uring_cqe cqe;
207 struct list_head list;
208};
209
269bbe5f
BM
210struct io_rsrc_put {
211 struct list_head list;
50238531
BM
212 union {
213 void *rsrc;
214 struct file *file;
215 };
269bbe5f
BM
216};
217
218struct fixed_rsrc_table {
65e19f54 219 struct file **files;
31b51510
JA
220};
221
269bbe5f 222struct fixed_rsrc_ref_node {
05589553
XW
223 struct percpu_ref refs;
224 struct list_head node;
269bbe5f
BM
225 struct list_head rsrc_list;
226 struct fixed_rsrc_data *rsrc_data;
50238531
BM
227 void (*rsrc_put)(struct io_ring_ctx *ctx,
228 struct io_rsrc_put *prsrc);
4a38aed2 229 struct llist_node llist;
e297822b 230 bool done;
05589553
XW
231};
232
269bbe5f
BM
233struct fixed_rsrc_data {
234 struct fixed_rsrc_table *table;
05f3fb3c
JA
235 struct io_ring_ctx *ctx;
236
269bbe5f 237 struct fixed_rsrc_ref_node *node;
05f3fb3c 238 struct percpu_ref refs;
05f3fb3c 239 struct completion done;
8bad28d8 240 bool quiesce;
05f3fb3c
JA
241};
242
5a2e745d
JA
243struct io_buffer {
244 struct list_head list;
245 __u64 addr;
246 __s32 len;
247 __u16 bid;
248};
249
21b55dbc
SG
250struct io_restriction {
251 DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
252 DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
253 u8 sqe_flags_allowed;
254 u8 sqe_flags_required;
7e84e1c7 255 bool registered;
21b55dbc
SG
256};
257
37d1e2e3
JA
258enum {
259 IO_SQ_THREAD_SHOULD_STOP = 0,
260 IO_SQ_THREAD_SHOULD_PARK,
261};
262
534ca6d6
JA
263struct io_sq_data {
264 refcount_t refs;
9e138a48 265 atomic_t park_pending;
09a6f4ef 266 struct mutex lock;
69fb2131
JA
267
268 /* ctx's that are using this sqd */
269 struct list_head ctx_list;
69fb2131 270
534ca6d6
JA
271 struct task_struct *thread;
272 struct wait_queue_head wait;
08369246
XW
273
274 unsigned sq_thread_idle;
37d1e2e3
JA
275 int sq_cpu;
276 pid_t task_pid;
5c2469e0 277 pid_t task_tgid;
37d1e2e3
JA
278
279 unsigned long state;
37d1e2e3 280 struct completion exited;
b7f5a0bf 281 struct callback_head *park_task_work;
534ca6d6
JA
282};
283
258b29a9 284#define IO_IOPOLL_BATCH 8
6dd0be1e 285#define IO_COMPL_BATCH 32
6ff119a6 286#define IO_REQ_CACHE_SIZE 32
bf019da7 287#define IO_REQ_ALLOC_BATCH 8
258b29a9
PB
288
289struct io_comp_state {
6dd0be1e 290 struct io_kiocb *reqs[IO_COMPL_BATCH];
1b4c351f 291 unsigned int nr;
c7dae4ba
JA
292 unsigned int locked_free_nr;
293 /* inline/task_work completion list, under ->uring_lock */
1b4c351f 294 struct list_head free_list;
c7dae4ba
JA
295 /* IRQ completion list, under ->completion_lock */
296 struct list_head locked_free_list;
258b29a9
PB
297};
298
a1ab7b35
PB
299struct io_submit_link {
300 struct io_kiocb *head;
301 struct io_kiocb *last;
302};
303
258b29a9
PB
304struct io_submit_state {
305 struct blk_plug plug;
a1ab7b35 306 struct io_submit_link link;
258b29a9
PB
307
308 /*
309 * io_kiocb alloc cache
310 */
bf019da7 311 void *reqs[IO_REQ_CACHE_SIZE];
258b29a9
PB
312 unsigned int free_reqs;
313
314 bool plug_started;
315
316 /*
317 * Batch completion logic
318 */
319 struct io_comp_state comp;
320
321 /*
322 * File reference cache
323 */
324 struct file *file;
325 unsigned int fd;
326 unsigned int file_refs;
327 unsigned int ios_left;
328};
329
2b188cc1
JA
330struct io_ring_ctx {
331 struct {
332 struct percpu_ref refs;
333 } ____cacheline_aligned_in_smp;
334
335 struct {
336 unsigned int flags;
e1d85334 337 unsigned int compat: 1;
e1d85334
RD
338 unsigned int cq_overflow_flushed: 1;
339 unsigned int drain_next: 1;
340 unsigned int eventfd_async: 1;
21b55dbc 341 unsigned int restricted: 1;
2b188cc1 342
75b28aff
HV
343 /*
344 * Ring buffer of indices into array of io_uring_sqe, which is
345 * mmapped by the application using the IORING_OFF_SQES offset.
346 *
347 * This indirection could e.g. be used to assign fixed
348 * io_uring_sqe entries to operations and only submit them to
349 * the queue when needed.
350 *
351 * The kernel modifies neither the indices array nor the entries
352 * array.
353 */
354 u32 *sq_array;
2b188cc1
JA
355 unsigned cached_sq_head;
356 unsigned sq_entries;
357 unsigned sq_mask;
6c271ce2 358 unsigned sq_thread_idle;
498ccd9e 359 unsigned cached_sq_dropped;
2c3bac6d 360 unsigned cached_cq_overflow;
ad3eb2c8 361 unsigned long sq_check_overflow;
de0617e4 362
e941894e
JA
363 /* hashed buffered write serialization */
364 struct io_wq_hash *hash_map;
365
de0617e4 366 struct list_head defer_list;
5262f567 367 struct list_head timeout_list;
1d7bb1d5 368 struct list_head cq_overflow_list;
fcb323cc 369
ad3eb2c8 370 struct io_uring_sqe *sq_sqes;
2b188cc1
JA
371 } ____cacheline_aligned_in_smp;
372
3c1a2ead
JA
373 struct {
374 struct mutex uring_lock;
375 wait_queue_head_t wait;
376 } ____cacheline_aligned_in_smp;
377
378 struct io_submit_state submit_state;
379
206aefde
JA
380 struct io_rings *rings;
381
2aede0e4
JA
382 /* Only used for accounting purposes */
383 struct mm_struct *mm_account;
384
7c30f36a 385 const struct cred *sq_creds; /* cred used for __io_sq_thread() */
534ca6d6
JA
386 struct io_sq_data *sq_data; /* if using sq thread polling */
387
90554200 388 struct wait_queue_head sqo_sq_wait;
69fb2131 389 struct list_head sqd_list;
75b28aff 390
6b06314c
JA
391 /*
392 * If used, fixed file set. Writers must ensure that ->refs is dead,
393 * readers must ensure that ->refs is alive as long as the file* is
394 * used. Only updated through io_uring_register(2).
395 */
269bbe5f 396 struct fixed_rsrc_data *file_data;
6b06314c
JA
397 unsigned nr_user_files;
398
edafccee
JA
399 /* if used, fixed mapped user buffers */
400 unsigned nr_user_bufs;
401 struct io_mapped_ubuf *user_bufs;
402
2b188cc1
JA
403 struct user_struct *user;
404
0f158b4c 405 struct completion ref_comp;
206aefde
JA
406
407#if defined(CONFIG_UNIX)
408 struct socket *ring_sock;
409#endif
410
9e15c3a0 411 struct xarray io_buffers;
5a2e745d 412
61cf9370
MWO
413 struct xarray personalities;
414 u32 pers_next;
071698e1 415
206aefde
JA
416 struct {
417 unsigned cached_cq_tail;
418 unsigned cq_entries;
419 unsigned cq_mask;
420 atomic_t cq_timeouts;
f010505b 421 unsigned cq_last_tm_flush;
ad3eb2c8 422 unsigned long cq_check_overflow;
206aefde
JA
423 struct wait_queue_head cq_wait;
424 struct fasync_struct *cq_fasync;
425 struct eventfd_ctx *cq_ev_fd;
426 } ____cacheline_aligned_in_smp;
2b188cc1 427
2b188cc1
JA
428 struct {
429 spinlock_t completion_lock;
e94f141b 430
def596e9 431 /*
540e32a0 432 * ->iopoll_list is protected by the ctx->uring_lock for
def596e9
JA
433 * io_uring instances that don't use IORING_SETUP_SQPOLL.
434 * For SQPOLL, only the single threaded io_sq_thread() will
435 * manipulate the list, hence no extra locking is needed there.
436 */
540e32a0 437 struct list_head iopoll_list;
78076bb6
JA
438 struct hlist_head *cancel_hash;
439 unsigned cancel_hash_bits;
e94f141b 440 bool poll_multi_file;
31b51510 441
fcb323cc
JA
442 spinlock_t inflight_lock;
443 struct list_head inflight_list;
2b188cc1 444 } ____cacheline_aligned_in_smp;
85faa7b8 445
269bbe5f
BM
446 struct delayed_work rsrc_put_work;
447 struct llist_head rsrc_put_llist;
d67d2263
BM
448 struct list_head rsrc_ref_list;
449 spinlock_t rsrc_ref_lock;
8dd03afe 450 struct fixed_rsrc_ref_node *rsrc_backup_node;
4a38aed2 451
21b55dbc 452 struct io_restriction restrictions;
3c1a2ead 453
7c25c0d1
JA
454 /* exit task_work */
455 struct callback_head *exit_task_work;
456
e941894e
JA
457 struct wait_queue_head hash_wait;
458
3c1a2ead
JA
459 /* Keep this last, we don't need it for the fast path */
460 struct work_struct exit_work;
13bf43f5 461 struct list_head tctx_list;
2b188cc1
JA
462};
463
53e043b2
SM
464struct io_uring_task {
465 /* submission side */
466 struct xarray xa;
467 struct wait_queue_head wait;
ee53fb2b
SM
468 const struct io_ring_ctx *last;
469 struct io_wq *io_wq;
53e043b2
SM
470 struct percpu_counter inflight;
471 atomic_t in_idle;
53e043b2
SM
472
473 spinlock_t task_lock;
474 struct io_wq_work_list task_list;
475 unsigned long task_state;
476 struct callback_head task_work;
477};
478
09bb8394
JA
479/*
480 * First field must be the file pointer in all the
481 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
482 */
221c5eb2
JA
483struct io_poll_iocb {
484 struct file *file;
018043be 485 struct wait_queue_head *head;
221c5eb2 486 __poll_t events;
8c838788 487 bool done;
221c5eb2 488 bool canceled;
b69de288
JA
489 bool update_events;
490 bool update_user_data;
491 union {
492 struct wait_queue_entry wait;
493 struct {
494 u64 old_user_data;
495 u64 new_user_data;
496 };
497 };
221c5eb2
JA
498};
499
018043be
PB
500struct io_poll_remove {
501 struct file *file;
502 u64 addr;
503};
504
b5dba59e
JA
505struct io_close {
506 struct file *file;
b5dba59e
JA
507 int fd;
508};
509
ad8a48ac
JA
510struct io_timeout_data {
511 struct io_kiocb *req;
512 struct hrtimer timer;
513 struct timespec64 ts;
514 enum hrtimer_mode mode;
515};
516
8ed8d3c3
JA
517struct io_accept {
518 struct file *file;
519 struct sockaddr __user *addr;
520 int __user *addr_len;
521 int flags;
09952e3e 522 unsigned long nofile;
8ed8d3c3
JA
523};
524
525struct io_sync {
526 struct file *file;
527 loff_t len;
528 loff_t off;
529 int flags;
d63d1b5e 530 int mode;
8ed8d3c3
JA
531};
532
fbf23849
JA
533struct io_cancel {
534 struct file *file;
535 u64 addr;
536};
537
b29472ee
JA
538struct io_timeout {
539 struct file *file;
bfe68a22
PB
540 u32 off;
541 u32 target_seq;
135fcde8 542 struct list_head list;
90cd7e42
PB
543 /* head of the link, used by linked timeouts only */
544 struct io_kiocb *head;
b29472ee
JA
545};
546
0bdf7a2d
PB
547struct io_timeout_rem {
548 struct file *file;
549 u64 addr;
9c8e11b3
PB
550
551 /* timeout update */
552 struct timespec64 ts;
553 u32 flags;
0bdf7a2d
PB
554};
555
9adbd45d
JA
556struct io_rw {
557 /* NOTE: kiocb has the file as the first member, so don't do it here */
558 struct kiocb kiocb;
559 u64 addr;
560 u64 len;
561};
562
3fbb51c1
JA
563struct io_connect {
564 struct file *file;
565 struct sockaddr __user *addr;
566 int addr_len;
567};
568
e47293fd
JA
569struct io_sr_msg {
570 struct file *file;
fddaface 571 union {
270a5940 572 struct user_msghdr __user *umsg;
fddaface
JA
573 void __user *buf;
574 };
e47293fd 575 int msg_flags;
bcda7baa 576 int bgid;
fddaface 577 size_t len;
bcda7baa 578 struct io_buffer *kbuf;
e47293fd
JA
579};
580
15b71abe
JA
581struct io_open {
582 struct file *file;
583 int dfd;
15b71abe 584 struct filename *filename;
c12cedf2 585 struct open_how how;
4022e7af 586 unsigned long nofile;
15b71abe
JA
587};
588
269bbe5f 589struct io_rsrc_update {
05f3fb3c
JA
590 struct file *file;
591 u64 arg;
592 u32 nr_args;
593 u32 offset;
594};
595
4840e418
JA
596struct io_fadvise {
597 struct file *file;
598 u64 offset;
599 u32 len;
600 u32 advice;
601};
602
c1ca757b
JA
603struct io_madvise {
604 struct file *file;
605 u64 addr;
606 u32 len;
607 u32 advice;
608};
609
3e4827b0
JA
610struct io_epoll {
611 struct file *file;
612 int epfd;
613 int op;
614 int fd;
615 struct epoll_event event;
e47293fd
JA
616};
617
7d67af2c
PB
618struct io_splice {
619 struct file *file_out;
620 struct file *file_in;
621 loff_t off_out;
622 loff_t off_in;
623 u64 len;
624 unsigned int flags;
625};
626
ddf0322d
JA
627struct io_provide_buf {
628 struct file *file;
629 __u64 addr;
630 __s32 len;
631 __u32 bgid;
632 __u16 nbufs;
633 __u16 bid;
634};
635
1d9e1288
BM
636struct io_statx {
637 struct file *file;
638 int dfd;
639 unsigned int mask;
640 unsigned int flags;
e62753e4 641 const char __user *filename;
1d9e1288
BM
642 struct statx __user *buffer;
643};
644
36f4fa68
JA
645struct io_shutdown {
646 struct file *file;
647 int how;
648};
649
80a261fd
JA
650struct io_rename {
651 struct file *file;
652 int old_dfd;
653 int new_dfd;
654 struct filename *oldpath;
655 struct filename *newpath;
656 int flags;
657};
658
14a1143b
JA
659struct io_unlink {
660 struct file *file;
661 int dfd;
662 int flags;
663 struct filename *filename;
664};
665
3ca405eb
PB
666struct io_completion {
667 struct file *file;
668 struct list_head list;
8c3f9cd1 669 u32 cflags;
3ca405eb
PB
670};
671
f499a021
JA
672struct io_async_connect {
673 struct sockaddr_storage address;
674};
675
03b1230c
JA
676struct io_async_msghdr {
677 struct iovec fast_iov[UIO_FASTIOV];
257e84a5
PB
678 /* points to an allocated iov, if NULL we use fast_iov instead */
679 struct iovec *free_iov;
03b1230c
JA
680 struct sockaddr __user *uaddr;
681 struct msghdr msg;
b537916c 682 struct sockaddr_storage addr;
03b1230c
JA
683};
684
f67676d1
JA
685struct io_async_rw {
686 struct iovec fast_iov[UIO_FASTIOV];
ff6165b2
JA
687 const struct iovec *free_iovec;
688 struct iov_iter iter;
227c0c96 689 size_t bytes_done;
bcf5a063 690 struct wait_page_queue wpq;
f67676d1
JA
691};
692
6b47ee6e
PB
693enum {
694 REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
695 REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
696 REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
697 REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
698 REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
bcda7baa 699 REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
6b47ee6e 700
6b47ee6e
PB
701 REQ_F_FAIL_LINK_BIT,
702 REQ_F_INFLIGHT_BIT,
703 REQ_F_CUR_POS_BIT,
704 REQ_F_NOWAIT_BIT,
6b47ee6e 705 REQ_F_LINK_TIMEOUT_BIT,
99bc4c38 706 REQ_F_NEED_CLEANUP_BIT,
d7718a9d 707 REQ_F_POLLED_BIT,
bcda7baa 708 REQ_F_BUFFER_SELECTED_BIT,
900fad45 709 REQ_F_LTIMEOUT_ACTIVE_BIT,
e342c807 710 REQ_F_COMPLETE_INLINE_BIT,
230d50d4 711 REQ_F_REISSUE_BIT,
8c130827 712 REQ_F_DONT_REISSUE_BIT,
7b29f92d
JA
713 /* keep async read/write and isreg together and in order */
714 REQ_F_ASYNC_READ_BIT,
715 REQ_F_ASYNC_WRITE_BIT,
716 REQ_F_ISREG_BIT,
84557871
JA
717
718 /* not a real bit, just to check we're not overflowing the space */
719 __REQ_F_LAST_BIT,
6b47ee6e
PB
720};
721
722enum {
723 /* ctx owns file */
724 REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
725 /* drain existing IO first */
726 REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
727 /* linked sqes */
728 REQ_F_LINK = BIT(REQ_F_LINK_BIT),
729 /* doesn't sever on completion < 0 */
730 REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
731 /* IOSQE_ASYNC */
732 REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
bcda7baa
JA
733 /* IOSQE_BUFFER_SELECT */
734 REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
6b47ee6e 735
6b47ee6e
PB
736 /* fail rest of links */
737 REQ_F_FAIL_LINK = BIT(REQ_F_FAIL_LINK_BIT),
b05a1bcd 738 /* on inflight list, should be cancelled and waited on exit reliably */
6b47ee6e
PB
739 REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
740 /* read/write uses file position */
741 REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
742 /* must not punt to workers */
743 REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
900fad45 744 /* has or had linked timeout */
6b47ee6e 745 REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
99bc4c38
PB
746 /* needs cleanup */
747 REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
d7718a9d
JA
748 /* already went through poll handler */
749 REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
bcda7baa
JA
750 /* buffer already selected */
751 REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
900fad45
PB
752 /* linked timeout is active, i.e. prepared by link's head */
753 REQ_F_LTIMEOUT_ACTIVE = BIT(REQ_F_LTIMEOUT_ACTIVE_BIT),
e342c807
PB
754 /* completion is deferred through io_comp_state */
755 REQ_F_COMPLETE_INLINE = BIT(REQ_F_COMPLETE_INLINE_BIT),
230d50d4
JA
756 /* caller should reissue async */
757 REQ_F_REISSUE = BIT(REQ_F_REISSUE_BIT),
8c130827
PB
758 /* don't attempt request reissue, see io_rw_reissue() */
759 REQ_F_DONT_REISSUE = BIT(REQ_F_DONT_REISSUE_BIT),
7b29f92d
JA
760 /* supports async reads */
761 REQ_F_ASYNC_READ = BIT(REQ_F_ASYNC_READ_BIT),
762 /* supports async writes */
763 REQ_F_ASYNC_WRITE = BIT(REQ_F_ASYNC_WRITE_BIT),
764 /* regular file */
765 REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
d7718a9d
JA
766};
767
768struct async_poll {
769 struct io_poll_iocb poll;
807abcb0 770 struct io_poll_iocb *double_poll;
6b47ee6e
PB
771};
772
7cbf1722
JA
773struct io_task_work {
774 struct io_wq_work_node node;
775 task_work_func_t func;
776};
777
09bb8394
JA
778/*
779 * NOTE! Each of the iocb union members has the file pointer
780 * as the first entry in their struct definition. So you can
781 * access the file pointer through any of the sub-structs,
782 * or directly as just 'ki_filp' in this struct.
783 */
2b188cc1 784struct io_kiocb {
221c5eb2 785 union {
09bb8394 786 struct file *file;
9adbd45d 787 struct io_rw rw;
221c5eb2 788 struct io_poll_iocb poll;
018043be 789 struct io_poll_remove poll_remove;
8ed8d3c3
JA
790 struct io_accept accept;
791 struct io_sync sync;
fbf23849 792 struct io_cancel cancel;
b29472ee 793 struct io_timeout timeout;
0bdf7a2d 794 struct io_timeout_rem timeout_rem;
3fbb51c1 795 struct io_connect connect;
e47293fd 796 struct io_sr_msg sr_msg;
15b71abe 797 struct io_open open;
b5dba59e 798 struct io_close close;
269bbe5f 799 struct io_rsrc_update rsrc_update;
4840e418 800 struct io_fadvise fadvise;
c1ca757b 801 struct io_madvise madvise;
3e4827b0 802 struct io_epoll epoll;
7d67af2c 803 struct io_splice splice;
ddf0322d 804 struct io_provide_buf pbuf;
1d9e1288 805 struct io_statx statx;
36f4fa68 806 struct io_shutdown shutdown;
80a261fd 807 struct io_rename rename;
14a1143b 808 struct io_unlink unlink;
3ca405eb
PB
809 /* use only after cleaning per-op data, see io_clean_op() */
810 struct io_completion compl;
221c5eb2 811 };
2b188cc1 812
e8c2bc1f
JA
813 /* opcode allocated if it needs to store data for async defer */
814 void *async_data;
d625c6ee 815 u8 opcode;
65a6543d
XW
816 /* polled IO has completed */
817 u8 iopoll_completed;
2b188cc1 818
4f4eeba8 819 u16 buf_index;
9cf7c104 820 u32 result;
4f4eeba8 821
010e8e6b
PB
822 struct io_ring_ctx *ctx;
823 unsigned int flags;
abc54d63 824 atomic_t refs;
010e8e6b
PB
825 struct task_struct *task;
826 u64 user_data;
d7718a9d 827
f2f87370 828 struct io_kiocb *link;
269bbe5f 829 struct percpu_ref *fixed_rsrc_refs;
fcb323cc 830
d21ffe7e
PB
831 /*
832 * 1. used with ctx->iopoll_list with reads/writes
833 * 2. to track reqs with ->files (see io_op_def::file_table)
834 */
010e8e6b 835 struct list_head inflight_entry;
7cbf1722
JA
836 union {
837 struct io_task_work io_task_work;
838 struct callback_head task_work;
839 };
010e8e6b
PB
840 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
841 struct hlist_node hash_node;
842 struct async_poll *apoll;
843 struct io_wq_work work;
2b188cc1 844};
05589553 845
13bf43f5
PB
846struct io_tctx_node {
847 struct list_head ctx_node;
848 struct task_struct *task;
13bf43f5
PB
849 struct io_ring_ctx *ctx;
850};
851
27dc8338
PB
852struct io_defer_entry {
853 struct list_head list;
854 struct io_kiocb *req;
9cf7c104 855 u32 seq;
2b188cc1
JA
856};
857
d3656344 858struct io_op_def {
d3656344
JA
859 /* needs req->file assigned */
860 unsigned needs_file : 1;
d3656344
JA
861 /* hash wq insertion if file is a regular file */
862 unsigned hash_reg_file : 1;
863 /* unbound wq insertion if file is a non-regular file */
864 unsigned unbound_nonreg_file : 1;
66f4af93
JA
865 /* opcode is not supported by this kernel */
866 unsigned not_supported : 1;
8a72758c
JA
867 /* set if opcode supports polled "wait" */
868 unsigned pollin : 1;
869 unsigned pollout : 1;
bcda7baa
JA
870 /* op supports buffer selection */
871 unsigned buffer_select : 1;
26f0505a
PB
872 /* do prep async if is going to be punted */
873 unsigned needs_async_setup : 1;
27926b68
JA
874 /* should block plug */
875 unsigned plug : 1;
e8c2bc1f
JA
876 /* size of async data needed, if any */
877 unsigned short async_size;
d3656344
JA
878};
879
0918682b 880static const struct io_op_def io_op_defs[] = {
0463b6c5
PB
881 [IORING_OP_NOP] = {},
882 [IORING_OP_READV] = {
d3656344
JA
883 .needs_file = 1,
884 .unbound_nonreg_file = 1,
8a72758c 885 .pollin = 1,
4d954c25 886 .buffer_select = 1,
26f0505a 887 .needs_async_setup = 1,
27926b68 888 .plug = 1,
e8c2bc1f 889 .async_size = sizeof(struct io_async_rw),
d3656344 890 },
0463b6c5 891 [IORING_OP_WRITEV] = {
d3656344
JA
892 .needs_file = 1,
893 .hash_reg_file = 1,
894 .unbound_nonreg_file = 1,
8a72758c 895 .pollout = 1,
26f0505a 896 .needs_async_setup = 1,
27926b68 897 .plug = 1,
e8c2bc1f 898 .async_size = sizeof(struct io_async_rw),
d3656344 899 },
0463b6c5 900 [IORING_OP_FSYNC] = {
d3656344
JA
901 .needs_file = 1,
902 },
0463b6c5 903 [IORING_OP_READ_FIXED] = {
d3656344
JA
904 .needs_file = 1,
905 .unbound_nonreg_file = 1,
8a72758c 906 .pollin = 1,
27926b68 907 .plug = 1,
e8c2bc1f 908 .async_size = sizeof(struct io_async_rw),
d3656344 909 },
0463b6c5 910 [IORING_OP_WRITE_FIXED] = {
d3656344
JA
911 .needs_file = 1,
912 .hash_reg_file = 1,
913 .unbound_nonreg_file = 1,
8a72758c 914 .pollout = 1,
27926b68 915 .plug = 1,
e8c2bc1f 916 .async_size = sizeof(struct io_async_rw),
d3656344 917 },
0463b6c5 918 [IORING_OP_POLL_ADD] = {
d3656344
JA
919 .needs_file = 1,
920 .unbound_nonreg_file = 1,
921 },
0463b6c5
PB
922 [IORING_OP_POLL_REMOVE] = {},
923 [IORING_OP_SYNC_FILE_RANGE] = {
d3656344
JA
924 .needs_file = 1,
925 },
0463b6c5 926 [IORING_OP_SENDMSG] = {
d3656344
JA
927 .needs_file = 1,
928 .unbound_nonreg_file = 1,
8a72758c 929 .pollout = 1,
26f0505a 930 .needs_async_setup = 1,
e8c2bc1f 931 .async_size = sizeof(struct io_async_msghdr),
d3656344 932 },
0463b6c5 933 [IORING_OP_RECVMSG] = {
d3656344
JA
934 .needs_file = 1,
935 .unbound_nonreg_file = 1,
8a72758c 936 .pollin = 1,
52de1fe1 937 .buffer_select = 1,
26f0505a 938 .needs_async_setup = 1,
e8c2bc1f 939 .async_size = sizeof(struct io_async_msghdr),
d3656344 940 },
0463b6c5 941 [IORING_OP_TIMEOUT] = {
e8c2bc1f 942 .async_size = sizeof(struct io_timeout_data),
d3656344 943 },
9c8e11b3
PB
944 [IORING_OP_TIMEOUT_REMOVE] = {
945 /* used by timeout updates' prep() */
9c8e11b3 946 },
0463b6c5 947 [IORING_OP_ACCEPT] = {
d3656344
JA
948 .needs_file = 1,
949 .unbound_nonreg_file = 1,
8a72758c 950 .pollin = 1,
d3656344 951 },
0463b6c5
PB
952 [IORING_OP_ASYNC_CANCEL] = {},
953 [IORING_OP_LINK_TIMEOUT] = {
e8c2bc1f 954 .async_size = sizeof(struct io_timeout_data),
d3656344 955 },
0463b6c5 956 [IORING_OP_CONNECT] = {
d3656344
JA
957 .needs_file = 1,
958 .unbound_nonreg_file = 1,
8a72758c 959 .pollout = 1,
26f0505a 960 .needs_async_setup = 1,
e8c2bc1f 961 .async_size = sizeof(struct io_async_connect),
d3656344 962 },
0463b6c5 963 [IORING_OP_FALLOCATE] = {
d3656344 964 .needs_file = 1,
d3656344 965 },
44526bed
JA
966 [IORING_OP_OPENAT] = {},
967 [IORING_OP_CLOSE] = {},
968 [IORING_OP_FILES_UPDATE] = {},
969 [IORING_OP_STATX] = {},
0463b6c5 970 [IORING_OP_READ] = {
3a6820f2
JA
971 .needs_file = 1,
972 .unbound_nonreg_file = 1,
8a72758c 973 .pollin = 1,
bcda7baa 974 .buffer_select = 1,
27926b68 975 .plug = 1,
e8c2bc1f 976 .async_size = sizeof(struct io_async_rw),
3a6820f2 977 },
0463b6c5 978 [IORING_OP_WRITE] = {
3a6820f2
JA
979 .needs_file = 1,
980 .unbound_nonreg_file = 1,
8a72758c 981 .pollout = 1,
27926b68 982 .plug = 1,
e8c2bc1f 983 .async_size = sizeof(struct io_async_rw),
3a6820f2 984 },
0463b6c5 985 [IORING_OP_FADVISE] = {
4840e418 986 .needs_file = 1,
c1ca757b 987 },
44526bed 988 [IORING_OP_MADVISE] = {},
0463b6c5 989 [IORING_OP_SEND] = {
fddaface
JA
990 .needs_file = 1,
991 .unbound_nonreg_file = 1,
8a72758c 992 .pollout = 1,
fddaface 993 },
0463b6c5 994 [IORING_OP_RECV] = {
fddaface
JA
995 .needs_file = 1,
996 .unbound_nonreg_file = 1,
8a72758c 997 .pollin = 1,
bcda7baa 998 .buffer_select = 1,
fddaface 999 },
0463b6c5 1000 [IORING_OP_OPENAT2] = {
cebdb986 1001 },
3e4827b0
JA
1002 [IORING_OP_EPOLL_CTL] = {
1003 .unbound_nonreg_file = 1,
3e4827b0 1004 },
7d67af2c
PB
1005 [IORING_OP_SPLICE] = {
1006 .needs_file = 1,
1007 .hash_reg_file = 1,
1008 .unbound_nonreg_file = 1,
ddf0322d
JA
1009 },
1010 [IORING_OP_PROVIDE_BUFFERS] = {},
067524e9 1011 [IORING_OP_REMOVE_BUFFERS] = {},
f2a8d5c7
PB
1012 [IORING_OP_TEE] = {
1013 .needs_file = 1,
1014 .hash_reg_file = 1,
1015 .unbound_nonreg_file = 1,
1016 },
36f4fa68
JA
1017 [IORING_OP_SHUTDOWN] = {
1018 .needs_file = 1,
1019 },
44526bed
JA
1020 [IORING_OP_RENAMEAT] = {},
1021 [IORING_OP_UNLINKAT] = {},
d3656344
JA
1022};
1023
7a612350 1024static bool io_disarm_next(struct io_kiocb *req);
d56d938b 1025static void io_uring_del_task_file(unsigned long index);
9936c7c2
PB
1026static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
1027 struct task_struct *task,
1028 struct files_struct *files);
37d1e2e3 1029static void io_uring_cancel_sqpoll(struct io_ring_ctx *ctx);
269bbe5f 1030static void destroy_fixed_rsrc_ref_node(struct fixed_rsrc_ref_node *ref_node);
bc9744cd 1031static struct fixed_rsrc_ref_node *alloc_fixed_rsrc_ref_node(
1ffc5422 1032 struct io_ring_ctx *ctx);
f2303b1f 1033static void io_ring_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
1ffc5422 1034
78e19bbe 1035static void io_cqring_fill_event(struct io_kiocb *req, long res);
ec9c02ad 1036static void io_put_req(struct io_kiocb *req);
216578e5 1037static void io_put_req_deferred(struct io_kiocb *req, int nr);
c7dae4ba
JA
1038static void io_dismantle_req(struct io_kiocb *req);
1039static void io_put_task(struct task_struct *task, int nr);
1040static void io_queue_next(struct io_kiocb *req);
94ae5e77
JA
1041static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req);
1042static void io_queue_linked_timeout(struct io_kiocb *req);
05f3fb3c 1043static int __io_sqe_files_update(struct io_ring_ctx *ctx,
269bbe5f 1044 struct io_uring_rsrc_update *ip,
05f3fb3c 1045 unsigned nr_args);
68fb8979 1046static void io_clean_op(struct io_kiocb *req);
8371adf5
PB
1047static struct file *io_file_get(struct io_submit_state *state,
1048 struct io_kiocb *req, int fd, bool fixed);
c5eef2b9 1049static void __io_queue_sqe(struct io_kiocb *req);
269bbe5f 1050static void io_rsrc_put_work(struct work_struct *work);
de0617e4 1051
907d1df3 1052static void io_req_task_queue(struct io_kiocb *req);
65453d1e
JA
1053static void io_submit_flush_completions(struct io_comp_state *cs,
1054 struct io_ring_ctx *ctx);
5082620f 1055static bool io_poll_remove_waitqs(struct io_kiocb *req);
179ae0d1 1056static int io_req_prep_async(struct io_kiocb *req);
de0617e4 1057
2b188cc1
JA
1058static struct kmem_cache *req_cachep;
1059
0918682b 1060static const struct file_operations io_uring_fops;
2b188cc1
JA
1061
1062struct sock *io_uring_get_socket(struct file *file)
1063{
1064#if defined(CONFIG_UNIX)
1065 if (file->f_op == &io_uring_fops) {
1066 struct io_ring_ctx *ctx = file->private_data;
1067
1068 return ctx->ring_sock->sk;
1069 }
1070#endif
1071 return NULL;
1072}
1073EXPORT_SYMBOL(io_uring_get_socket);
1074
f2f87370
PB
1075#define io_for_each_link(pos, head) \
1076 for (pos = (head); pos; pos = pos->link)
1077
36f72fe2
PB
1078static inline void io_set_resource_node(struct io_kiocb *req)
1079{
1080 struct io_ring_ctx *ctx = req->ctx;
1081
269bbe5f
BM
1082 if (!req->fixed_rsrc_refs) {
1083 req->fixed_rsrc_refs = &ctx->file_data->node->refs;
1084 percpu_ref_get(req->fixed_rsrc_refs);
36f72fe2
PB
1085 }
1086}
1087
08d23634
PB
1088static bool io_match_task(struct io_kiocb *head,
1089 struct task_struct *task,
1090 struct files_struct *files)
1091{
1092 struct io_kiocb *req;
1093
68207680 1094 if (task && head->task != task)
08d23634
PB
1095 return false;
1096 if (!files)
1097 return true;
1098
1099 io_for_each_link(req, head) {
b05a1bcd 1100 if (req->flags & REQ_F_INFLIGHT)
02a13674 1101 return true;
08d23634
PB
1102 }
1103 return false;
1104}
1105
c40f6379
JA
1106static inline void req_set_fail_links(struct io_kiocb *req)
1107{
1108 if ((req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) == REQ_F_LINK)
1109 req->flags |= REQ_F_FAIL_LINK;
1110}
4a38aed2 1111
2b188cc1
JA
1112static void io_ring_ctx_ref_free(struct percpu_ref *ref)
1113{
1114 struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
1115
0f158b4c 1116 complete(&ctx->ref_comp);
2b188cc1
JA
1117}
1118
8eb7e2d0
PB
1119static inline bool io_is_timeout_noseq(struct io_kiocb *req)
1120{
1121 return !req->timeout.off;
1122}
1123
2b188cc1
JA
1124static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
1125{
1126 struct io_ring_ctx *ctx;
78076bb6 1127 int hash_bits;
2b188cc1
JA
1128
1129 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1130 if (!ctx)
1131 return NULL;
1132
78076bb6
JA
1133 /*
1134 * Use 5 bits less than the max cq entries, that should give us around
1135 * 32 entries per hash list if totally full and uniformly spread.
1136 */
1137 hash_bits = ilog2(p->cq_entries);
1138 hash_bits -= 5;
1139 if (hash_bits <= 0)
1140 hash_bits = 1;
1141 ctx->cancel_hash_bits = hash_bits;
1142 ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
1143 GFP_KERNEL);
1144 if (!ctx->cancel_hash)
1145 goto err;
1146 __hash_init(ctx->cancel_hash, 1U << hash_bits);
1147
21482896 1148 if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
206aefde
JA
1149 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
1150 goto err;
2b188cc1
JA
1151
1152 ctx->flags = p->flags;
90554200 1153 init_waitqueue_head(&ctx->sqo_sq_wait);
69fb2131 1154 INIT_LIST_HEAD(&ctx->sqd_list);
2b188cc1 1155 init_waitqueue_head(&ctx->cq_wait);
1d7bb1d5 1156 INIT_LIST_HEAD(&ctx->cq_overflow_list);
0f158b4c 1157 init_completion(&ctx->ref_comp);
9e15c3a0 1158 xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
61cf9370 1159 xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
2b188cc1
JA
1160 mutex_init(&ctx->uring_lock);
1161 init_waitqueue_head(&ctx->wait);
1162 spin_lock_init(&ctx->completion_lock);
540e32a0 1163 INIT_LIST_HEAD(&ctx->iopoll_list);
de0617e4 1164 INIT_LIST_HEAD(&ctx->defer_list);
5262f567 1165 INIT_LIST_HEAD(&ctx->timeout_list);
fcb323cc
JA
1166 spin_lock_init(&ctx->inflight_lock);
1167 INIT_LIST_HEAD(&ctx->inflight_list);
d67d2263
BM
1168 spin_lock_init(&ctx->rsrc_ref_lock);
1169 INIT_LIST_HEAD(&ctx->rsrc_ref_list);
269bbe5f
BM
1170 INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
1171 init_llist_head(&ctx->rsrc_put_llist);
13bf43f5 1172 INIT_LIST_HEAD(&ctx->tctx_list);
1b4c351f 1173 INIT_LIST_HEAD(&ctx->submit_state.comp.free_list);
c7dae4ba 1174 INIT_LIST_HEAD(&ctx->submit_state.comp.locked_free_list);
2b188cc1 1175 return ctx;
206aefde 1176err:
78076bb6 1177 kfree(ctx->cancel_hash);
206aefde
JA
1178 kfree(ctx);
1179 return NULL;
2b188cc1
JA
1180}
1181
9cf7c104 1182static bool req_need_defer(struct io_kiocb *req, u32 seq)
7adf4eaf 1183{
2bc9930e
JA
1184 if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
1185 struct io_ring_ctx *ctx = req->ctx;
a197f664 1186
9cf7c104 1187 return seq != ctx->cached_cq_tail
2c3bac6d 1188 + READ_ONCE(ctx->cached_cq_overflow);
2bc9930e 1189 }
de0617e4 1190
9d858b21 1191 return false;
de0617e4
JA
1192}
1193
ce3d5aae
PB
1194static void io_req_track_inflight(struct io_kiocb *req)
1195{
1196 struct io_ring_ctx *ctx = req->ctx;
1197
1198 if (!(req->flags & REQ_F_INFLIGHT)) {
ce3d5aae
PB
1199 req->flags |= REQ_F_INFLIGHT;
1200
1201 spin_lock_irq(&ctx->inflight_lock);
1202 list_add(&req->inflight_entry, &ctx->inflight_list);
1203 spin_unlock_irq(&ctx->inflight_lock);
1204 }
1205}
1206
1e6fa521
JA
1207static void io_prep_async_work(struct io_kiocb *req)
1208{
1209 const struct io_op_def *def = &io_op_defs[req->opcode];
1e6fa521
JA
1210 struct io_ring_ctx *ctx = req->ctx;
1211
003e8dcc
JA
1212 if (!req->work.creds)
1213 req->work.creds = get_current_cred();
1214
e1d675df
PB
1215 req->work.list.next = NULL;
1216 req->work.flags = 0;
feaadc4f
PB
1217 if (req->flags & REQ_F_FORCE_ASYNC)
1218 req->work.flags |= IO_WQ_WORK_CONCURRENT;
1219
1e6fa521
JA
1220 if (req->flags & REQ_F_ISREG) {
1221 if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
1222 io_wq_hash_work(&req->work, file_inode(req->file));
4b982bd0 1223 } else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
1e6fa521
JA
1224 if (def->unbound_nonreg_file)
1225 req->work.flags |= IO_WQ_WORK_UNBOUND;
1226 }
e1d675df
PB
1227
1228 switch (req->opcode) {
1229 case IORING_OP_SPLICE:
1230 case IORING_OP_TEE:
1231 /*
1232 * Splice operation will be punted aync, and here need to
1233 * modify io_wq_work.flags, so initialize io_wq_work firstly.
1234 */
1235 if (!S_ISREG(file_inode(req->splice.file_in)->i_mode))
1236 req->work.flags |= IO_WQ_WORK_UNBOUND;
1237 break;
1238 }
561fb04a 1239}
cccf0ee8 1240
cbdcb435 1241static void io_prep_async_link(struct io_kiocb *req)
561fb04a 1242{
cbdcb435 1243 struct io_kiocb *cur;
54a91f3b 1244
f2f87370
PB
1245 io_for_each_link(cur, req)
1246 io_prep_async_work(cur);
561fb04a
JA
1247}
1248
ebf93667 1249static void io_queue_async_work(struct io_kiocb *req)
561fb04a 1250{
a197f664 1251 struct io_ring_ctx *ctx = req->ctx;
cbdcb435 1252 struct io_kiocb *link = io_prep_linked_timeout(req);
5aa75ed5 1253 struct io_uring_task *tctx = req->task->io_uring;
561fb04a 1254
3bfe6106
JA
1255 BUG_ON(!tctx);
1256 BUG_ON(!tctx->io_wq);
561fb04a 1257
cbdcb435
PB
1258 /* init ->work of the whole link before punting */
1259 io_prep_async_link(req);
d07f1e8a
PB
1260 trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
1261 &req->work, req->flags);
ebf93667 1262 io_wq_enqueue(tctx->io_wq, &req->work);
7271ef3a
JA
1263 if (link)
1264 io_queue_linked_timeout(link);
cbdcb435
PB
1265}
1266
1ee4160c 1267static void io_kill_timeout(struct io_kiocb *req, int status)
5262f567 1268{
e8c2bc1f 1269 struct io_timeout_data *io = req->async_data;
5262f567
JA
1270 int ret;
1271
e8c2bc1f 1272 ret = hrtimer_try_to_cancel(&io->timer);
5262f567 1273 if (ret != -1) {
01cec8c1
PB
1274 atomic_set(&req->ctx->cq_timeouts,
1275 atomic_read(&req->ctx->cq_timeouts) + 1);
135fcde8 1276 list_del_init(&req->timeout.list);
1ee4160c 1277 io_cqring_fill_event(req, status);
216578e5 1278 io_put_req_deferred(req, 1);
5262f567
JA
1279 }
1280}
1281
04518945 1282static void __io_queue_deferred(struct io_ring_ctx *ctx)
de0617e4 1283{
04518945 1284 do {
27dc8338
PB
1285 struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
1286 struct io_defer_entry, list);
de0617e4 1287
9cf7c104 1288 if (req_need_defer(de->req, de->seq))
04518945 1289 break;
27dc8338 1290 list_del_init(&de->list);
907d1df3 1291 io_req_task_queue(de->req);
27dc8338 1292 kfree(de);
04518945
PB
1293 } while (!list_empty(&ctx->defer_list));
1294}
1295
360428f8 1296static void io_flush_timeouts(struct io_ring_ctx *ctx)
de0617e4 1297{
f010505b
MDG
1298 u32 seq;
1299
1300 if (list_empty(&ctx->timeout_list))
1301 return;
1302
1303 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
1304
1305 do {
1306 u32 events_needed, events_got;
360428f8 1307 struct io_kiocb *req = list_first_entry(&ctx->timeout_list,
135fcde8 1308 struct io_kiocb, timeout.list);
de0617e4 1309
8eb7e2d0 1310 if (io_is_timeout_noseq(req))
360428f8 1311 break;
f010505b
MDG
1312
1313 /*
1314 * Since seq can easily wrap around over time, subtract
1315 * the last seq at which timeouts were flushed before comparing.
1316 * Assuming not more than 2^31-1 events have happened since,
1317 * these subtractions won't have wrapped, so we can check if
1318 * target is in [last_seq, current_seq] by comparing the two.
1319 */
1320 events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
1321 events_got = seq - ctx->cq_last_tm_flush;
1322 if (events_got < events_needed)
360428f8 1323 break;
bfe68a22 1324
135fcde8 1325 list_del_init(&req->timeout.list);
1ee4160c 1326 io_kill_timeout(req, 0);
f010505b
MDG
1327 } while (!list_empty(&ctx->timeout_list));
1328
1329 ctx->cq_last_tm_flush = seq;
360428f8 1330}
5262f567 1331
360428f8
PB
1332static void io_commit_cqring(struct io_ring_ctx *ctx)
1333{
1334 io_flush_timeouts(ctx);
ec30e04b
PB
1335
1336 /* order cqe stores with ring update */
1337 smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
de0617e4 1338
04518945
PB
1339 if (unlikely(!list_empty(&ctx->defer_list)))
1340 __io_queue_deferred(ctx);
de0617e4
JA
1341}
1342
90554200
JA
1343static inline bool io_sqring_full(struct io_ring_ctx *ctx)
1344{
1345 struct io_rings *r = ctx->rings;
1346
1347 return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == r->sq_ring_entries;
1348}
1349
888aae2e
PB
1350static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
1351{
1352 return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
1353}
1354
2b188cc1
JA
1355static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx)
1356{
75b28aff 1357 struct io_rings *rings = ctx->rings;
2b188cc1
JA
1358 unsigned tail;
1359
115e12e5
SB
1360 /*
1361 * writes to the cq entry need to come after reading head; the
1362 * control dependency is enough as we're using WRITE_ONCE to
1363 * fill the cq entry
1364 */
888aae2e 1365 if (__io_cqring_events(ctx) == rings->cq_ring_entries)
2b188cc1
JA
1366 return NULL;
1367
888aae2e 1368 tail = ctx->cached_cq_tail++;
75b28aff 1369 return &rings->cqes[tail & ctx->cq_mask];
2b188cc1
JA
1370}
1371
f2842ab5
JA
1372static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
1373{
f0b493e6
JA
1374 if (!ctx->cq_ev_fd)
1375 return false;
7e55a19c
SG
1376 if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
1377 return false;
f2842ab5
JA
1378 if (!ctx->eventfd_async)
1379 return true;
b41e9852 1380 return io_wq_current_is_worker();
f2842ab5
JA
1381}
1382
b41e9852 1383static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
1d7bb1d5 1384{
b1445e59
PB
1385 /* see waitqueue_active() comment */
1386 smp_mb();
1387
1d7bb1d5
JA
1388 if (waitqueue_active(&ctx->wait))
1389 wake_up(&ctx->wait);
534ca6d6
JA
1390 if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
1391 wake_up(&ctx->sq_data->wait);
b41e9852 1392 if (io_should_trigger_evfd(ctx))
1d7bb1d5 1393 eventfd_signal(ctx->cq_ev_fd, 1);
b1445e59 1394 if (waitqueue_active(&ctx->cq_wait)) {
4aa84f2f
PB
1395 wake_up_interruptible(&ctx->cq_wait);
1396 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
1397 }
1d7bb1d5
JA
1398}
1399
80c18e4a
PB
1400static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
1401{
b1445e59
PB
1402 /* see waitqueue_active() comment */
1403 smp_mb();
1404
80c18e4a
PB
1405 if (ctx->flags & IORING_SETUP_SQPOLL) {
1406 if (waitqueue_active(&ctx->wait))
1407 wake_up(&ctx->wait);
1408 }
1409 if (io_should_trigger_evfd(ctx))
1410 eventfd_signal(ctx->cq_ev_fd, 1);
b1445e59 1411 if (waitqueue_active(&ctx->cq_wait)) {
4aa84f2f
PB
1412 wake_up_interruptible(&ctx->cq_wait);
1413 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
1414 }
80c18e4a
PB
1415}
1416
c4a2ed72 1417/* Returns true if there are no backlogged entries after the flush */
6c2450ae 1418static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
1d7bb1d5
JA
1419{
1420 struct io_rings *rings = ctx->rings;
1d7bb1d5 1421 unsigned long flags;
b18032bb 1422 bool all_flushed, posted;
1d7bb1d5 1423
e23de15f
PB
1424 if (!force && __io_cqring_events(ctx) == rings->cq_ring_entries)
1425 return false;
1d7bb1d5 1426
b18032bb 1427 posted = false;
1d7bb1d5 1428 spin_lock_irqsave(&ctx->completion_lock, flags);
6c2450ae
PB
1429 while (!list_empty(&ctx->cq_overflow_list)) {
1430 struct io_uring_cqe *cqe = io_get_cqring(ctx);
1431 struct io_overflow_cqe *ocqe;
e6c8aa9a 1432
1d7bb1d5
JA
1433 if (!cqe && !force)
1434 break;
6c2450ae
PB
1435 ocqe = list_first_entry(&ctx->cq_overflow_list,
1436 struct io_overflow_cqe, list);
1437 if (cqe)
1438 memcpy(cqe, &ocqe->cqe, sizeof(*cqe));
1439 else
1d7bb1d5 1440 WRITE_ONCE(ctx->rings->cq_overflow,
6c2450ae 1441 ++ctx->cached_cq_overflow);
b18032bb 1442 posted = true;
6c2450ae
PB
1443 list_del(&ocqe->list);
1444 kfree(ocqe);
1d7bb1d5
JA
1445 }
1446
09e88404
PB
1447 all_flushed = list_empty(&ctx->cq_overflow_list);
1448 if (all_flushed) {
1449 clear_bit(0, &ctx->sq_check_overflow);
1450 clear_bit(0, &ctx->cq_check_overflow);
1451 ctx->rings->sq_flags &= ~IORING_SQ_CQ_OVERFLOW;
1452 }
46930143 1453
b18032bb
JA
1454 if (posted)
1455 io_commit_cqring(ctx);
1d7bb1d5 1456 spin_unlock_irqrestore(&ctx->completion_lock, flags);
b18032bb
JA
1457 if (posted)
1458 io_cqring_ev_posted(ctx);
09e88404 1459 return all_flushed;
1d7bb1d5
JA
1460}
1461
6c2450ae 1462static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
6c503150 1463{
ca0a2651
JA
1464 bool ret = true;
1465
6c503150
PB
1466 if (test_bit(0, &ctx->cq_check_overflow)) {
1467 /* iopoll syncs against uring_lock, not completion_lock */
1468 if (ctx->flags & IORING_SETUP_IOPOLL)
1469 mutex_lock(&ctx->uring_lock);
6c2450ae 1470 ret = __io_cqring_overflow_flush(ctx, force);
6c503150
PB
1471 if (ctx->flags & IORING_SETUP_IOPOLL)
1472 mutex_unlock(&ctx->uring_lock);
1473 }
ca0a2651
JA
1474
1475 return ret;
6c503150
PB
1476}
1477
abc54d63
JA
1478/*
1479 * Shamelessly stolen from the mm implementation of page reference checking,
1480 * see commit f958d7b528b1 for details.
1481 */
1482#define req_ref_zero_or_close_to_overflow(req) \
1483 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1484
de9b4cca
JA
1485static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
1486{
abc54d63 1487 return atomic_inc_not_zero(&req->refs);
de9b4cca
JA
1488}
1489
1490static inline bool req_ref_sub_and_test(struct io_kiocb *req, int refs)
1491{
abc54d63
JA
1492 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1493 return atomic_sub_and_test(refs, &req->refs);
de9b4cca
JA
1494}
1495
1496static inline bool req_ref_put_and_test(struct io_kiocb *req)
1497{
abc54d63
JA
1498 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1499 return atomic_dec_and_test(&req->refs);
de9b4cca
JA
1500}
1501
1502static inline void req_ref_put(struct io_kiocb *req)
1503{
abc54d63 1504 WARN_ON_ONCE(req_ref_put_and_test(req));
de9b4cca
JA
1505}
1506
1507static inline void req_ref_get(struct io_kiocb *req)
1508{
abc54d63
JA
1509 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1510 atomic_inc(&req->refs);
de9b4cca
JA
1511}
1512
5082620f 1513static bool __io_cqring_fill_event(struct io_kiocb *req, long res,
8c3f9cd1 1514 unsigned int cflags)
2b188cc1 1515{
78e19bbe 1516 struct io_ring_ctx *ctx = req->ctx;
2b188cc1
JA
1517 struct io_uring_cqe *cqe;
1518
7471e1af 1519 trace_io_uring_complete(ctx, req->user_data, res, cflags);
51c3ff62 1520
2b188cc1
JA
1521 /*
1522 * If we can't get a cq entry, userspace overflowed the
1523 * submission (by quite a lot). Increment the overflow count in
1524 * the ring.
1525 */
1526 cqe = io_get_cqring(ctx);
1d7bb1d5 1527 if (likely(cqe)) {
78e19bbe 1528 WRITE_ONCE(cqe->user_data, req->user_data);
2b188cc1 1529 WRITE_ONCE(cqe->res, res);
bcda7baa 1530 WRITE_ONCE(cqe->flags, cflags);
5082620f 1531 return true;
6c2450ae
PB
1532 }
1533 if (!ctx->cq_overflow_flushed &&
1534 !atomic_read(&req->task->io_uring->in_idle)) {
1535 struct io_overflow_cqe *ocqe;
1536
1537 ocqe = kmalloc(sizeof(*ocqe), GFP_ATOMIC | __GFP_ACCOUNT);
1538 if (!ocqe)
1539 goto overflow;
ad3eb2c8
JA
1540 if (list_empty(&ctx->cq_overflow_list)) {
1541 set_bit(0, &ctx->sq_check_overflow);
1542 set_bit(0, &ctx->cq_check_overflow);
6d5f9049 1543 ctx->rings->sq_flags |= IORING_SQ_CQ_OVERFLOW;
ad3eb2c8 1544 }
6c2450ae
PB
1545 ocqe->cqe.user_data = req->user_data;
1546 ocqe->cqe.res = res;
1547 ocqe->cqe.flags = cflags;
1548 list_add_tail(&ocqe->list, &ctx->cq_overflow_list);
5082620f 1549 return true;
2b188cc1 1550 }
6c2450ae
PB
1551overflow:
1552 /*
1553 * If we're in ring overflow flush mode, or in task cancel mode,
1554 * or cannot allocate an overflow entry, then we need to drop it
1555 * on the floor.
1556 */
1557 WRITE_ONCE(ctx->rings->cq_overflow, ++ctx->cached_cq_overflow);
5082620f 1558 return false;
2b188cc1
JA
1559}
1560
bcda7baa
JA
1561static void io_cqring_fill_event(struct io_kiocb *req, long res)
1562{
1563 __io_cqring_fill_event(req, res, 0);
1564}
1565
7a612350
PB
1566static void io_req_complete_post(struct io_kiocb *req, long res,
1567 unsigned int cflags)
2b188cc1 1568{
78e19bbe 1569 struct io_ring_ctx *ctx = req->ctx;
2b188cc1
JA
1570 unsigned long flags;
1571
1572 spin_lock_irqsave(&ctx->completion_lock, flags);
bcda7baa 1573 __io_cqring_fill_event(req, res, cflags);
c7dae4ba
JA
1574 /*
1575 * If we're the last reference to this request, add to our locked
1576 * free_list cache.
1577 */
de9b4cca 1578 if (req_ref_put_and_test(req)) {
c7dae4ba
JA
1579 struct io_comp_state *cs = &ctx->submit_state.comp;
1580
7a612350
PB
1581 if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
1582 if (req->flags & (REQ_F_LINK_TIMEOUT | REQ_F_FAIL_LINK))
1583 io_disarm_next(req);
1584 if (req->link) {
1585 io_req_task_queue(req->link);
1586 req->link = NULL;
1587 }
1588 }
c7dae4ba
JA
1589 io_dismantle_req(req);
1590 io_put_task(req->task, 1);
1591 list_add(&req->compl.list, &cs->locked_free_list);
1592 cs->locked_free_nr++;
180f829f
PB
1593 } else {
1594 if (!percpu_ref_tryget(&ctx->refs))
1595 req = NULL;
1596 }
7a612350 1597 io_commit_cqring(ctx);
2b188cc1 1598 spin_unlock_irqrestore(&ctx->completion_lock, flags);
7a612350 1599
180f829f
PB
1600 if (req) {
1601 io_cqring_ev_posted(ctx);
c7dae4ba 1602 percpu_ref_put(&ctx->refs);
180f829f 1603 }
229a7b63
JA
1604}
1605
a38d68db 1606static void io_req_complete_state(struct io_kiocb *req, long res,
889fca73 1607 unsigned int cflags)
229a7b63 1608{
68fb8979
PB
1609 if (req->flags & (REQ_F_NEED_CLEANUP | REQ_F_BUFFER_SELECTED))
1610 io_clean_op(req);
a38d68db
PB
1611 req->result = res;
1612 req->compl.cflags = cflags;
e342c807 1613 req->flags |= REQ_F_COMPLETE_INLINE;
e1e16097
JA
1614}
1615
889fca73
PB
1616static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
1617 long res, unsigned cflags)
bcda7baa 1618{
889fca73
PB
1619 if (issue_flags & IO_URING_F_COMPLETE_DEFER)
1620 io_req_complete_state(req, res, cflags);
a38d68db 1621 else
c7dae4ba 1622 io_req_complete_post(req, res, cflags);
bcda7baa
JA
1623}
1624
a38d68db 1625static inline void io_req_complete(struct io_kiocb *req, long res)
0ddf92e8 1626{
889fca73 1627 __io_req_complete(req, 0, res, 0);
0ddf92e8
JA
1628}
1629
f41db273
PB
1630static void io_req_complete_failed(struct io_kiocb *req, long res)
1631{
1632 req_set_fail_links(req);
1633 io_put_req(req);
1634 io_req_complete_post(req, res, 0);
1635}
1636
dac7a098
PB
1637static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx,
1638 struct io_comp_state *cs)
1639{
1640 spin_lock_irq(&ctx->completion_lock);
1641 list_splice_init(&cs->locked_free_list, &cs->free_list);
1642 cs->locked_free_nr = 0;
1643 spin_unlock_irq(&ctx->completion_lock);
1644}
1645
dd78f492 1646/* Returns true IFF there are requests in the cache */
c7dae4ba 1647static bool io_flush_cached_reqs(struct io_ring_ctx *ctx)
0ddf92e8 1648{
c7dae4ba
JA
1649 struct io_submit_state *state = &ctx->submit_state;
1650 struct io_comp_state *cs = &state->comp;
dd78f492 1651 int nr;
0ddf92e8 1652
c7dae4ba
JA
1653 /*
1654 * If we have more than a batch's worth of requests in our IRQ side
1655 * locked cache, grab the lock and move them over to our submission
1656 * side cache.
1657 */
dac7a098
PB
1658 if (READ_ONCE(cs->locked_free_nr) > IO_COMPL_BATCH)
1659 io_flush_cached_locked_reqs(ctx, cs);
0ddf92e8 1660
dd78f492 1661 nr = state->free_reqs;
c7dae4ba 1662 while (!list_empty(&cs->free_list)) {
dd78f492
PB
1663 struct io_kiocb *req = list_first_entry(&cs->free_list,
1664 struct io_kiocb, compl.list);
1665
1b4c351f 1666 list_del(&req->compl.list);
dd78f492
PB
1667 state->reqs[nr++] = req;
1668 if (nr == ARRAY_SIZE(state->reqs))
e5d1bc0a 1669 break;
1b4c351f
JA
1670 }
1671
dd78f492
PB
1672 state->free_reqs = nr;
1673 return nr != 0;
0ddf92e8
JA
1674}
1675
e5d1bc0a 1676static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
2b188cc1 1677{
e5d1bc0a
PB
1678 struct io_submit_state *state = &ctx->submit_state;
1679
1680 BUILD_BUG_ON(IO_REQ_ALLOC_BATCH > ARRAY_SIZE(state->reqs));
1681
f6b6c7d6 1682 if (!state->free_reqs) {
291b2821 1683 gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
2579f913
JA
1684 int ret;
1685
c7dae4ba 1686 if (io_flush_cached_reqs(ctx))
e5d1bc0a
PB
1687 goto got_req;
1688
bf019da7
PB
1689 ret = kmem_cache_alloc_bulk(req_cachep, gfp, IO_REQ_ALLOC_BATCH,
1690 state->reqs);
fd6fab2c
JA
1691
1692 /*
1693 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1694 * retry single alloc to be on the safe side.
1695 */
1696 if (unlikely(ret <= 0)) {
1697 state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
1698 if (!state->reqs[0])
3893f39f 1699 return NULL;
fd6fab2c
JA
1700 ret = 1;
1701 }
291b2821 1702 state->free_reqs = ret;
2b188cc1 1703 }
e5d1bc0a 1704got_req:
291b2821
PB
1705 state->free_reqs--;
1706 return state->reqs[state->free_reqs];
2b188cc1
JA
1707}
1708
e1d767f0 1709static inline void io_put_file(struct file *file)
8da11c19 1710{
e1d767f0 1711 if (file)
8da11c19
PB
1712 fput(file);
1713}
1714
4edf20f9 1715static void io_dismantle_req(struct io_kiocb *req)
2b188cc1 1716{
094bae49
PB
1717 unsigned int flags = req->flags;
1718
e1d767f0
PB
1719 if (!(flags & REQ_F_FIXED_FILE))
1720 io_put_file(req->file);
094bae49
PB
1721 if (flags & (REQ_F_NEED_CLEANUP | REQ_F_BUFFER_SELECTED |
1722 REQ_F_INFLIGHT)) {
1723 io_clean_op(req);
1724
1725 if (req->flags & REQ_F_INFLIGHT) {
1726 struct io_ring_ctx *ctx = req->ctx;
1727 unsigned long flags;
1728
1729 spin_lock_irqsave(&ctx->inflight_lock, flags);
1730 list_del(&req->inflight_entry);
1731 spin_unlock_irqrestore(&ctx->inflight_lock, flags);
1732 req->flags &= ~REQ_F_INFLIGHT;
1733 }
1734 }
269bbe5f
BM
1735 if (req->fixed_rsrc_refs)
1736 percpu_ref_put(req->fixed_rsrc_refs);
094bae49
PB
1737 if (req->async_data)
1738 kfree(req->async_data);
003e8dcc
JA
1739 if (req->work.creds) {
1740 put_cred(req->work.creds);
1741 req->work.creds = NULL;
1742 }
e65ef56d
JA
1743}
1744
b23fcf47 1745/* must to be called somewhat shortly after putting a request */
7c660731
PB
1746static inline void io_put_task(struct task_struct *task, int nr)
1747{
1748 struct io_uring_task *tctx = task->io_uring;
1749
1750 percpu_counter_sub(&tctx->inflight, nr);
1751 if (unlikely(atomic_read(&tctx->in_idle)))
1752 wake_up(&tctx->wait);
1753 put_task_struct_many(task, nr);
1754}
1755
216578e5 1756static void __io_free_req(struct io_kiocb *req)
c6ca97b3 1757{
51a4cc11 1758 struct io_ring_ctx *ctx = req->ctx;
c6ca97b3 1759
216578e5 1760 io_dismantle_req(req);
7c660731 1761 io_put_task(req->task, 1);
c6ca97b3 1762
3893f39f 1763 kmem_cache_free(req_cachep, req);
ecfc5177 1764 percpu_ref_put(&ctx->refs);
e65ef56d
JA
1765}
1766
f2f87370
PB
1767static inline void io_remove_next_linked(struct io_kiocb *req)
1768{
1769 struct io_kiocb *nxt = req->link;
1770
1771 req->link = nxt->link;
1772 nxt->link = NULL;
1773}
1774
33cc89a9
PB
1775static bool io_kill_linked_timeout(struct io_kiocb *req)
1776 __must_hold(&req->ctx->completion_lock)
2665abfd 1777{
33cc89a9 1778 struct io_kiocb *link = req->link;
f2f87370 1779
900fad45
PB
1780 /*
1781 * Can happen if a linked timeout fired and link had been like
1782 * req -> link t-out -> link t-out [-> ...]
1783 */
c9abd7ad
PB
1784 if (link && (link->flags & REQ_F_LTIMEOUT_ACTIVE)) {
1785 struct io_timeout_data *io = link->async_data;
1786 int ret;
7c86ffee 1787
f2f87370 1788 io_remove_next_linked(req);
90cd7e42 1789 link->timeout.head = NULL;
c9abd7ad
PB
1790 ret = hrtimer_try_to_cancel(&io->timer);
1791 if (ret != -1) {
1792 io_cqring_fill_event(link, -ECANCELED);
33cc89a9 1793 io_put_req_deferred(link, 1);
d4729fbd 1794 return true;
c9abd7ad
PB
1795 }
1796 }
d4729fbd 1797 return false;
7c86ffee
PB
1798}
1799
d148ca4b 1800static void io_fail_links(struct io_kiocb *req)
33cc89a9 1801 __must_hold(&req->ctx->completion_lock)
9e645e11 1802{
33cc89a9 1803 struct io_kiocb *nxt, *link = req->link;
9e645e11 1804
f2f87370 1805 req->link = NULL;
f2f87370
PB
1806 while (link) {
1807 nxt = link->link;
1808 link->link = NULL;
2665abfd 1809
f2f87370 1810 trace_io_uring_fail_link(req, link);
7c86ffee 1811 io_cqring_fill_event(link, -ECANCELED);
1575f21a 1812 io_put_req_deferred(link, 2);
f2f87370 1813 link = nxt;
9e645e11 1814 }
33cc89a9 1815}
9e645e11 1816
33cc89a9
PB
1817static bool io_disarm_next(struct io_kiocb *req)
1818 __must_hold(&req->ctx->completion_lock)
1819{
1820 bool posted = false;
1821
1822 if (likely(req->flags & REQ_F_LINK_TIMEOUT))
1823 posted = io_kill_linked_timeout(req);
1824 if (unlikely(req->flags & REQ_F_FAIL_LINK)) {
1825 posted |= (req->link != NULL);
1826 io_fail_links(req);
1827 }
1828 return posted;
9e645e11
JA
1829}
1830
3fa5e0f3 1831static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
c69f8dbe 1832{
33cc89a9 1833 struct io_kiocb *nxt;
944e58bf 1834
9e645e11
JA
1835 /*
1836 * If LINK is set, we have dependent requests in this chain. If we
1837 * didn't fail this request, queue the first one up, moving any other
1838 * dependencies to the next request. In case of failure, fail the rest
1839 * of the chain.
1840 */
33cc89a9
PB
1841 if (req->flags & (REQ_F_LINK_TIMEOUT | REQ_F_FAIL_LINK)) {
1842 struct io_ring_ctx *ctx = req->ctx;
1843 unsigned long flags;
1844 bool posted;
1845
1846 spin_lock_irqsave(&ctx->completion_lock, flags);
1847 posted = io_disarm_next(req);
1848 if (posted)
1849 io_commit_cqring(req->ctx);
1850 spin_unlock_irqrestore(&ctx->completion_lock, flags);
1851 if (posted)
1852 io_cqring_ev_posted(ctx);
f2f87370 1853 }
33cc89a9
PB
1854 nxt = req->link;
1855 req->link = NULL;
1856 return nxt;
4d7dd462 1857}
9e645e11 1858
f2f87370 1859static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
3fa5e0f3 1860{
cdbff982 1861 if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK))))
3fa5e0f3
PB
1862 return NULL;
1863 return __io_req_find_next(req);
1864}
1865
2c32395d
PB
1866static void ctx_flush_and_put(struct io_ring_ctx *ctx)
1867{
1868 if (!ctx)
1869 return;
1870 if (ctx->submit_state.comp.nr) {
1871 mutex_lock(&ctx->uring_lock);
1872 io_submit_flush_completions(&ctx->submit_state.comp, ctx);
1873 mutex_unlock(&ctx->uring_lock);
1874 }
1875 percpu_ref_put(&ctx->refs);
1876}
1877
7cbf1722 1878static bool __tctx_task_work(struct io_uring_task *tctx)
c2c4c83c 1879{
65453d1e 1880 struct io_ring_ctx *ctx = NULL;
7cbf1722
JA
1881 struct io_wq_work_list list;
1882 struct io_wq_work_node *node;
c2c4c83c 1883
7cbf1722
JA
1884 if (wq_list_empty(&tctx->task_list))
1885 return false;
6200b0ae 1886
0b81e80c 1887 spin_lock_irq(&tctx->task_lock);
7cbf1722
JA
1888 list = tctx->task_list;
1889 INIT_WQ_LIST(&tctx->task_list);
0b81e80c 1890 spin_unlock_irq(&tctx->task_lock);
c2c4c83c 1891
7cbf1722
JA
1892 node = list.first;
1893 while (node) {
1894 struct io_wq_work_node *next = node->next;
1895 struct io_kiocb *req;
0ba9c9ed 1896
7cbf1722 1897 req = container_of(node, struct io_kiocb, io_task_work.node);
2c32395d
PB
1898 if (req->ctx != ctx) {
1899 ctx_flush_and_put(ctx);
1900 ctx = req->ctx;
1901 percpu_ref_get(&ctx->refs);
65453d1e 1902 }
65453d1e 1903
2c32395d
PB
1904 req->task_work.func(&req->task_work);
1905 node = next;
7cbf1722
JA
1906 }
1907
2c32395d 1908 ctx_flush_and_put(ctx);
7cbf1722 1909 return list.first != NULL;
c2c4c83c
JA
1910}
1911
7cbf1722 1912static void tctx_task_work(struct callback_head *cb)
c40f6379 1913{
7cbf1722 1914 struct io_uring_task *tctx = container_of(cb, struct io_uring_task, task_work);
c40f6379 1915
1d5f360d
JA
1916 clear_bit(0, &tctx->task_state);
1917
7cbf1722
JA
1918 while (__tctx_task_work(tctx))
1919 cond_resched();
7cbf1722
JA
1920}
1921
c15b79de 1922static int io_req_task_work_add(struct io_kiocb *req)
7cbf1722 1923{
c15b79de 1924 struct task_struct *tsk = req->task;
7cbf1722 1925 struct io_uring_task *tctx = tsk->io_uring;
c15b79de 1926 enum task_work_notify_mode notify;
7cbf1722 1927 struct io_wq_work_node *node, *prev;
0b81e80c 1928 unsigned long flags;
c15b79de
PB
1929 int ret = 0;
1930
1931 if (unlikely(tsk->flags & PF_EXITING))
1932 return -ESRCH;
7cbf1722
JA
1933
1934 WARN_ON_ONCE(!tctx);
1935
0b81e80c 1936 spin_lock_irqsave(&tctx->task_lock, flags);
7cbf1722 1937 wq_list_add_tail(&req->io_task_work.node, &tctx->task_list);
0b81e80c 1938 spin_unlock_irqrestore(&tctx->task_lock, flags);
7cbf1722
JA
1939
1940 /* task_work already pending, we're done */
1941 if (test_bit(0, &tctx->task_state) ||
1942 test_and_set_bit(0, &tctx->task_state))
1943 return 0;
1944
c15b79de
PB
1945 /*
1946 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
1947 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
1948 * processing task_work. There's no reliable way to tell if TWA_RESUME
1949 * will do the job.
1950 */
1951 notify = (req->ctx->flags & IORING_SETUP_SQPOLL) ? TWA_NONE : TWA_SIGNAL;
1952
1953 if (!task_work_add(tsk, &tctx->task_work, notify)) {
1954 wake_up_process(tsk);
7cbf1722 1955 return 0;
c15b79de 1956 }
7cbf1722
JA
1957
1958 /*
1959 * Slow path - we failed, find and delete work. if the work is not
1960 * in the list, it got run and we're fine.
1961 */
0b81e80c 1962 spin_lock_irqsave(&tctx->task_lock, flags);
7cbf1722
JA
1963 wq_list_for_each(node, prev, &tctx->task_list) {
1964 if (&req->io_task_work.node == node) {
1965 wq_list_del(&tctx->task_list, node, prev);
1966 ret = 1;
1967 break;
1968 }
1969 }
0b81e80c 1970 spin_unlock_irqrestore(&tctx->task_lock, flags);
7cbf1722
JA
1971 clear_bit(0, &tctx->task_state);
1972 return ret;
1973}
1974
9b465711
PB
1975static bool io_run_task_work_head(struct callback_head **work_head)
1976{
1977 struct callback_head *work, *next;
1978 bool executed = false;
1979
1980 do {
1981 work = xchg(work_head, NULL);
1982 if (!work)
1983 break;
1984
1985 do {
1986 next = work->next;
1987 work->func(work);
1988 work = next;
1989 cond_resched();
1990 } while (work);
1991 executed = true;
1992 } while (1);
1993
1994 return executed;
1995}
1996
1997static void io_task_work_add_head(struct callback_head **work_head,
1998 struct callback_head *task_work)
eab30c4d 1999{
7c25c0d1 2000 struct callback_head *head;
eab30c4d 2001
7c25c0d1 2002 do {
9b465711
PB
2003 head = READ_ONCE(*work_head);
2004 task_work->next = head;
2005 } while (cmpxchg(work_head, head, task_work) != head);
2006}
2007
2008static void io_req_task_work_add_fallback(struct io_kiocb *req,
2009 task_work_func_t cb)
2010{
2011 init_task_work(&req->task_work, cb);
2012 io_task_work_add_head(&req->ctx->exit_task_work, &req->task_work);
eab30c4d
PB
2013}
2014
c40f6379
JA
2015static void io_req_task_cancel(struct callback_head *cb)
2016{
2017 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
87ceb6a6 2018 struct io_ring_ctx *ctx = req->ctx;
c40f6379 2019
e83acd7d 2020 /* ctx is guaranteed to stay alive while we hold uring_lock */
792bb6eb 2021 mutex_lock(&ctx->uring_lock);
2593553a 2022 io_req_complete_failed(req, req->result);
792bb6eb 2023 mutex_unlock(&ctx->uring_lock);
c40f6379
JA
2024}
2025
2026static void __io_req_task_submit(struct io_kiocb *req)
2027{
2028 struct io_ring_ctx *ctx = req->ctx;
2029
04fc6c80 2030 /* ctx stays valid until unlock, even if we drop all ours ctx->refs */
81b6d05c 2031 mutex_lock(&ctx->uring_lock);
70aacfe6 2032 if (!(current->flags & PF_EXITING) && !current->in_execve)
c5eef2b9 2033 __io_queue_sqe(req);
81b6d05c 2034 else
2593553a 2035 io_req_complete_failed(req, -EFAULT);
81b6d05c 2036 mutex_unlock(&ctx->uring_lock);
c40f6379
JA
2037}
2038
2039static void io_req_task_submit(struct callback_head *cb)
2040{
2041 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
2042
2043 __io_req_task_submit(req);
2044}
2045
2c4b8eb6 2046static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
c40f6379 2047{
2c4b8eb6
PB
2048 req->result = ret;
2049 req->task_work.func = io_req_task_cancel;
c40f6379 2050
2c4b8eb6 2051 if (unlikely(io_req_task_work_add(req)))
eab30c4d 2052 io_req_task_work_add_fallback(req, io_req_task_cancel);
c40f6379
JA
2053}
2054
2c4b8eb6 2055static void io_req_task_queue(struct io_kiocb *req)
a3df7698 2056{
2c4b8eb6 2057 req->task_work.func = io_req_task_submit;
a3df7698
PB
2058
2059 if (unlikely(io_req_task_work_add(req)))
2c4b8eb6 2060 io_req_task_queue_fail(req, -ECANCELED);
a3df7698
PB
2061}
2062
f2f87370 2063static inline void io_queue_next(struct io_kiocb *req)
c69f8dbe 2064{
9b5f7bd9 2065 struct io_kiocb *nxt = io_req_find_next(req);
944e58bf
PB
2066
2067 if (nxt)
906a8c3f 2068 io_req_task_queue(nxt);
c69f8dbe
JL
2069}
2070
c3524383 2071static void io_free_req(struct io_kiocb *req)
7a743e22 2072{
c3524383
PB
2073 io_queue_next(req);
2074 __io_free_req(req);
2075}
8766dd51 2076
2d6500d4 2077struct req_batch {
5af1d13e
PB
2078 struct task_struct *task;
2079 int task_refs;
1b4c351f 2080 int ctx_refs;
2d6500d4
PB
2081};
2082
5af1d13e
PB
2083static inline void io_init_req_batch(struct req_batch *rb)
2084{
5af1d13e 2085 rb->task_refs = 0;
9ae72463 2086 rb->ctx_refs = 0;
5af1d13e
PB
2087 rb->task = NULL;
2088}
2089
2d6500d4
PB
2090static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
2091 struct req_batch *rb)
2092{
6e833d53 2093 if (rb->task)
7c660731 2094 io_put_task(rb->task, rb->task_refs);
9ae72463
PB
2095 if (rb->ctx_refs)
2096 percpu_ref_put_many(&ctx->refs, rb->ctx_refs);
2d6500d4
PB
2097}
2098
6ff119a6
PB
2099static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req,
2100 struct io_submit_state *state)
2d6500d4 2101{
f2f87370 2102 io_queue_next(req);
96670657 2103 io_dismantle_req(req);
2d6500d4 2104
e3bc8e9d 2105 if (req->task != rb->task) {
7c660731
PB
2106 if (rb->task)
2107 io_put_task(rb->task, rb->task_refs);
e3bc8e9d
JA
2108 rb->task = req->task;
2109 rb->task_refs = 0;
5af1d13e 2110 }
e3bc8e9d 2111 rb->task_refs++;
9ae72463 2112 rb->ctx_refs++;
5af1d13e 2113
bd759045 2114 if (state->free_reqs != ARRAY_SIZE(state->reqs))
6ff119a6 2115 state->reqs[state->free_reqs++] = req;
bd759045
PB
2116 else
2117 list_add(&req->compl.list, &state->comp.free_list);
7a743e22
PB
2118}
2119
905c172f
PB
2120static void io_submit_flush_completions(struct io_comp_state *cs,
2121 struct io_ring_ctx *ctx)
2122{
2123 int i, nr = cs->nr;
2124 struct io_kiocb *req;
2125 struct req_batch rb;
2126
2127 io_init_req_batch(&rb);
2128 spin_lock_irq(&ctx->completion_lock);
2129 for (i = 0; i < nr; i++) {
2130 req = cs->reqs[i];
2131 __io_cqring_fill_event(req, req->result, req->compl.cflags);
2132 }
2133 io_commit_cqring(ctx);
2134 spin_unlock_irq(&ctx->completion_lock);
2135
2136 io_cqring_ev_posted(ctx);
2137 for (i = 0; i < nr; i++) {
2138 req = cs->reqs[i];
2139
2140 /* submission and completion refs */
de9b4cca 2141 if (req_ref_sub_and_test(req, 2))
6ff119a6 2142 io_req_free_batch(&rb, req, &ctx->submit_state);
905c172f
PB
2143 }
2144
2145 io_req_free_batch_finish(ctx, &rb);
2146 cs->nr = 0;
7a743e22
PB
2147}
2148
ba816ad6
JA
2149/*
2150 * Drop reference to request, return next in chain (if there is one) if this
2151 * was the last reference to this request.
2152 */
0d85035a 2153static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
e65ef56d 2154{
9b5f7bd9
PB
2155 struct io_kiocb *nxt = NULL;
2156
de9b4cca 2157 if (req_ref_put_and_test(req)) {
9b5f7bd9 2158 nxt = io_req_find_next(req);
4d7dd462 2159 __io_free_req(req);
2a44f467 2160 }
9b5f7bd9 2161 return nxt;
2b188cc1
JA
2162}
2163
0d85035a 2164static inline void io_put_req(struct io_kiocb *req)
e65ef56d 2165{
de9b4cca 2166 if (req_ref_put_and_test(req))
e65ef56d 2167 io_free_req(req);
2b188cc1
JA
2168}
2169
216578e5
PB
2170static void io_put_req_deferred_cb(struct callback_head *cb)
2171{
2172 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
2173
2174 io_free_req(req);
2175}
2176
2177static void io_free_req_deferred(struct io_kiocb *req)
2178{
7cbf1722 2179 req->task_work.func = io_put_req_deferred_cb;
a05432fb 2180 if (unlikely(io_req_task_work_add(req)))
eab30c4d 2181 io_req_task_work_add_fallback(req, io_put_req_deferred_cb);
216578e5
PB
2182}
2183
2184static inline void io_put_req_deferred(struct io_kiocb *req, int refs)
2185{
de9b4cca 2186 if (req_ref_sub_and_test(req, refs))
216578e5
PB
2187 io_free_req_deferred(req);
2188}
2189
6c503150 2190static unsigned io_cqring_events(struct io_ring_ctx *ctx)
a3a0e43f
JA
2191{
2192 /* See comment at the top of this file */
2193 smp_rmb();
e23de15f 2194 return __io_cqring_events(ctx);
a3a0e43f
JA
2195}
2196
fb5ccc98
PB
2197static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
2198{
2199 struct io_rings *rings = ctx->rings;
2200
2201 /* make sure SQ entry isn't read before tail */
2202 return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
2203}
2204
8ff069bf 2205static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
e94f141b 2206{
8ff069bf 2207 unsigned int cflags;
e94f141b 2208
bcda7baa
JA
2209 cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
2210 cflags |= IORING_CQE_F_BUFFER;
0e1b6fe3 2211 req->flags &= ~REQ_F_BUFFER_SELECTED;
bcda7baa
JA
2212 kfree(kbuf);
2213 return cflags;
e94f141b
JA
2214}
2215
8ff069bf 2216static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
bcda7baa 2217{
4d954c25 2218 struct io_buffer *kbuf;
bcda7baa 2219
4d954c25 2220 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
8ff069bf
PB
2221 return io_put_kbuf(req, kbuf);
2222}
2223
4c6e277c
JA
2224static inline bool io_run_task_work(void)
2225{
6200b0ae
JA
2226 /*
2227 * Not safe to run on exiting task, and the task_work handling will
2228 * not add work to such a task.
2229 */
2230 if (unlikely(current->flags & PF_EXITING))
2231 return false;
4c6e277c
JA
2232 if (current->task_works) {
2233 __set_current_state(TASK_RUNNING);
2234 task_work_run();
2235 return true;
2236 }
2237
2238 return false;
bcda7baa
JA
2239}
2240
def596e9
JA
2241/*
2242 * Find and free completed poll iocbs
2243 */
2244static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
2245 struct list_head *done)
2246{
8237e045 2247 struct req_batch rb;
def596e9 2248 struct io_kiocb *req;
bbde017a
XW
2249
2250 /* order with ->result store in io_complete_rw_iopoll() */
2251 smp_rmb();
def596e9 2252
5af1d13e 2253 io_init_req_batch(&rb);
def596e9 2254 while (!list_empty(done)) {
bcda7baa
JA
2255 int cflags = 0;
2256
d21ffe7e 2257 req = list_first_entry(done, struct io_kiocb, inflight_entry);
f161340d
PB
2258 list_del(&req->inflight_entry);
2259
8c130827
PB
2260 if (READ_ONCE(req->result) == -EAGAIN &&
2261 !(req->flags & REQ_F_DONT_REISSUE)) {
bbde017a 2262 req->iopoll_completed = 0;
8c130827
PB
2263 req_ref_get(req);
2264 io_queue_async_work(req);
2265 continue;
bbde017a 2266 }
def596e9 2267
bcda7baa 2268 if (req->flags & REQ_F_BUFFER_SELECTED)
8ff069bf 2269 cflags = io_put_rw_kbuf(req);
bcda7baa
JA
2270
2271 __io_cqring_fill_event(req, req->result, cflags);
def596e9
JA
2272 (*nr_events)++;
2273
de9b4cca 2274 if (req_ref_put_and_test(req))
6ff119a6 2275 io_req_free_batch(&rb, req, &ctx->submit_state);
def596e9 2276 }
def596e9 2277
09bb8394 2278 io_commit_cqring(ctx);
80c18e4a 2279 io_cqring_ev_posted_iopoll(ctx);
2d6500d4 2280 io_req_free_batch_finish(ctx, &rb);
581f9810
BM
2281}
2282
def596e9
JA
2283static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
2284 long min)
2285{
2286 struct io_kiocb *req, *tmp;
2287 LIST_HEAD(done);
2288 bool spin;
2289 int ret;
2290
2291 /*
2292 * Only spin for completions if we don't have multiple devices hanging
2293 * off our complete list, and we're under the requested amount.
2294 */
2295 spin = !ctx->poll_multi_file && *nr_events < min;
2296
2297 ret = 0;
d21ffe7e 2298 list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
9adbd45d 2299 struct kiocb *kiocb = &req->rw.kiocb;
def596e9
JA
2300
2301 /*
581f9810
BM
2302 * Move completed and retryable entries to our local lists.
2303 * If we find a request that requires polling, break out
2304 * and complete those lists first, if we have entries there.
def596e9 2305 */
65a6543d 2306 if (READ_ONCE(req->iopoll_completed)) {
d21ffe7e 2307 list_move_tail(&req->inflight_entry, &done);
def596e9
JA
2308 continue;
2309 }
2310 if (!list_empty(&done))
2311 break;
2312
2313 ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin);
2314 if (ret < 0)
2315 break;
2316
3aadc23e
PB
2317 /* iopoll may have completed current req */
2318 if (READ_ONCE(req->iopoll_completed))
d21ffe7e 2319 list_move_tail(&req->inflight_entry, &done);
3aadc23e 2320
def596e9
JA
2321 if (ret && spin)
2322 spin = false;
2323 ret = 0;
2324 }
2325
2326 if (!list_empty(&done))
2327 io_iopoll_complete(ctx, nr_events, &done);
2328
2329 return ret;
2330}
2331
2332/*
d195a66e 2333 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
def596e9
JA
2334 * non-spinning poll check - we'll still enter the driver poll loop, but only
2335 * as a non-spinning completion check.
2336 */
2337static int io_iopoll_getevents(struct io_ring_ctx *ctx, unsigned int *nr_events,
2338 long min)
2339{
540e32a0 2340 while (!list_empty(&ctx->iopoll_list) && !need_resched()) {
def596e9
JA
2341 int ret;
2342
2343 ret = io_do_iopoll(ctx, nr_events, min);
2344 if (ret < 0)
2345 return ret;
eba0a4dd 2346 if (*nr_events >= min)
def596e9
JA
2347 return 0;
2348 }
2349
2350 return 1;
2351}
2352
2353/*
2354 * We can't just wait for polled events to come to us, we have to actively
2355 * find and complete them.
2356 */
b2edc0a7 2357static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
def596e9
JA
2358{
2359 if (!(ctx->flags & IORING_SETUP_IOPOLL))
2360 return;
2361
2362 mutex_lock(&ctx->uring_lock);
540e32a0 2363 while (!list_empty(&ctx->iopoll_list)) {
def596e9
JA
2364 unsigned int nr_events = 0;
2365
b2edc0a7 2366 io_do_iopoll(ctx, &nr_events, 0);
08f5439f 2367
b2edc0a7
PB
2368 /* let it sleep and repeat later if can't complete a request */
2369 if (nr_events == 0)
2370 break;
08f5439f
JA
2371 /*
2372 * Ensure we allow local-to-the-cpu processing to take place,
2373 * in this case we need to ensure that we reap all events.
3fcee5a6 2374 * Also let task_work, etc. to progress by releasing the mutex
08f5439f 2375 */
3fcee5a6
PB
2376 if (need_resched()) {
2377 mutex_unlock(&ctx->uring_lock);
2378 cond_resched();
2379 mutex_lock(&ctx->uring_lock);
2380 }
def596e9
JA
2381 }
2382 mutex_unlock(&ctx->uring_lock);
2383}
2384
7668b92a 2385static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
def596e9 2386{
7668b92a 2387 unsigned int nr_events = 0;
2b2ed975 2388 int iters = 0, ret = 0;
500f9fba 2389
c7849be9
XW
2390 /*
2391 * We disallow the app entering submit/complete with polling, but we
2392 * still need to lock the ring to prevent racing with polled issue
2393 * that got punted to a workqueue.
2394 */
2395 mutex_lock(&ctx->uring_lock);
def596e9 2396 do {
a3a0e43f
JA
2397 /*
2398 * Don't enter poll loop if we already have events pending.
2399 * If we do, we can potentially be spinning for commands that
2400 * already triggered a CQE (eg in error).
2401 */
6c503150 2402 if (test_bit(0, &ctx->cq_check_overflow))
6c2450ae 2403 __io_cqring_overflow_flush(ctx, false);
6c503150 2404 if (io_cqring_events(ctx))
a3a0e43f
JA
2405 break;
2406
500f9fba
JA
2407 /*
2408 * If a submit got punted to a workqueue, we can have the
2409 * application entering polling for a command before it gets
2410 * issued. That app will hold the uring_lock for the duration
2411 * of the poll right here, so we need to take a breather every
2412 * now and then to ensure that the issue has a chance to add
2413 * the poll to the issued list. Otherwise we can spin here
2414 * forever, while the workqueue is stuck trying to acquire the
2415 * very same mutex.
2416 */
2417 if (!(++iters & 7)) {
2418 mutex_unlock(&ctx->uring_lock);
4c6e277c 2419 io_run_task_work();
500f9fba
JA
2420 mutex_lock(&ctx->uring_lock);
2421 }
2422
7668b92a 2423 ret = io_iopoll_getevents(ctx, &nr_events, min);
def596e9
JA
2424 if (ret <= 0)
2425 break;
2426 ret = 0;
7668b92a 2427 } while (min && !nr_events && !need_resched());
def596e9 2428
500f9fba 2429 mutex_unlock(&ctx->uring_lock);
def596e9
JA
2430 return ret;
2431}
2432
491381ce 2433static void kiocb_end_write(struct io_kiocb *req)
2b188cc1 2434{
491381ce
JA
2435 /*
2436 * Tell lockdep we inherited freeze protection from submission
2437 * thread.
2438 */
2439 if (req->flags & REQ_F_ISREG) {
1c98679d 2440 struct super_block *sb = file_inode(req->file)->i_sb;
2b188cc1 2441
1c98679d
PB
2442 __sb_writers_acquired(sb, SB_FREEZE_WRITE);
2443 sb_end_write(sb);
2b188cc1
JA
2444 }
2445}
2446
b63534c4 2447#ifdef CONFIG_BLOCK
dc2a6e9a 2448static bool io_resubmit_prep(struct io_kiocb *req)
b63534c4 2449{
ab454438
PB
2450 struct io_async_rw *rw = req->async_data;
2451
2452 if (!rw)
2453 return !io_req_prep_async(req);
2454 /* may have left rw->iter inconsistent on -EIOCBQUEUED */
2455 iov_iter_revert(&rw->iter, req->result - iov_iter_count(&rw->iter));
2456 return true;
b63534c4 2457}
b63534c4 2458
3e6a0d3c 2459static bool io_rw_should_reissue(struct io_kiocb *req)
b63534c4 2460{
355afaeb 2461 umode_t mode = file_inode(req->file)->i_mode;
3e6a0d3c 2462 struct io_ring_ctx *ctx = req->ctx;
b63534c4 2463
355afaeb
JA
2464 if (!S_ISBLK(mode) && !S_ISREG(mode))
2465 return false;
3e6a0d3c
JA
2466 if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
2467 !(ctx->flags & IORING_SETUP_IOPOLL)))
b63534c4 2468 return false;
7c977a58
JA
2469 /*
2470 * If ref is dying, we might be running poll reap from the exit work.
2471 * Don't attempt to reissue from that path, just let it fail with
2472 * -EAGAIN.
2473 */
3e6a0d3c
JA
2474 if (percpu_ref_is_dying(&ctx->refs))
2475 return false;
2476 return true;
2477}
e82ad485
JA
2478#else
2479static bool io_rw_should_reissue(struct io_kiocb *req)
2480{
2481 return false;
2482}
3e6a0d3c
JA
2483#endif
2484
a1d7c393 2485static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
889fca73 2486 unsigned int issue_flags)
a1d7c393 2487{
2f8e45f1
PB
2488 int cflags = 0;
2489
b65c128f
PB
2490 if (req->rw.kiocb.ki_flags & IOCB_WRITE)
2491 kiocb_end_write(req);
9532b99b
PB
2492 if (res != req->result) {
2493 if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
2494 io_rw_should_reissue(req)) {
2495 req->flags |= REQ_F_REISSUE;
2496 return;
2497 }
2f8e45f1 2498 req_set_fail_links(req);
9532b99b 2499 }
2f8e45f1
PB
2500 if (req->flags & REQ_F_BUFFER_SELECTED)
2501 cflags = io_put_rw_kbuf(req);
2502 __io_req_complete(req, issue_flags, res, cflags);
ba816ad6
JA
2503}
2504
2505static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
2506{
9adbd45d 2507 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
ba816ad6 2508
889fca73 2509 __io_complete_rw(req, res, res2, 0);
2b188cc1
JA
2510}
2511
def596e9
JA
2512static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
2513{
9adbd45d 2514 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
def596e9 2515
491381ce
JA
2516 if (kiocb->ki_flags & IOCB_WRITE)
2517 kiocb_end_write(req);
9532b99b
PB
2518 if (unlikely(res != req->result)) {
2519 bool fail = true;
def596e9 2520
9532b99b
PB
2521#ifdef CONFIG_BLOCK
2522 if (res == -EAGAIN && io_rw_should_reissue(req) &&
2523 io_resubmit_prep(req))
2524 fail = false;
2525#endif
2526 if (fail) {
2527 req_set_fail_links(req);
2528 req->flags |= REQ_F_DONT_REISSUE;
2529 }
8c130827 2530 }
bbde017a
XW
2531
2532 WRITE_ONCE(req->result, res);
b9b0e0d3 2533 /* order with io_iopoll_complete() checking ->result */
cd664b0e
PB
2534 smp_wmb();
2535 WRITE_ONCE(req->iopoll_completed, 1);
def596e9
JA
2536}
2537
2538/*
2539 * After the iocb has been issued, it's safe to be found on the poll list.
2540 * Adding the kiocb to the list AFTER submission ensures that we don't
2541 * find it from a io_iopoll_getevents() thread before the issuer is done
2542 * accessing the kiocb cookie.
2543 */
2e9dbe90 2544static void io_iopoll_req_issued(struct io_kiocb *req, bool in_async)
def596e9
JA
2545{
2546 struct io_ring_ctx *ctx = req->ctx;
2547
2548 /*
2549 * Track whether we have multiple files in our lists. This will impact
2550 * how we do polling eventually, not spinning if we're on potentially
2551 * different devices.
2552 */
540e32a0 2553 if (list_empty(&ctx->iopoll_list)) {
def596e9
JA
2554 ctx->poll_multi_file = false;
2555 } else if (!ctx->poll_multi_file) {
2556 struct io_kiocb *list_req;
2557
540e32a0 2558 list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
d21ffe7e 2559 inflight_entry);
9adbd45d 2560 if (list_req->file != req->file)
def596e9
JA
2561 ctx->poll_multi_file = true;
2562 }
2563
2564 /*
2565 * For fast devices, IO may have already completed. If it has, add
2566 * it to the front so we find it first.
2567 */
65a6543d 2568 if (READ_ONCE(req->iopoll_completed))
d21ffe7e 2569 list_add(&req->inflight_entry, &ctx->iopoll_list);
def596e9 2570 else
d21ffe7e 2571 list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
bdcd3eab 2572
2e9dbe90
XW
2573 /*
2574 * If IORING_SETUP_SQPOLL is enabled, sqes are either handled in sq thread
2575 * task context or in io worker task context. If current task context is
2576 * sq thread, we don't need to check whether should wake up sq thread.
2577 */
2578 if (in_async && (ctx->flags & IORING_SETUP_SQPOLL) &&
534ca6d6
JA
2579 wq_has_sleeper(&ctx->sq_data->wait))
2580 wake_up(&ctx->sq_data->wait);
def596e9
JA
2581}
2582
9f13c35b
PB
2583static inline void io_state_file_put(struct io_submit_state *state)
2584{
02b23a9a
PB
2585 if (state->file_refs) {
2586 fput_many(state->file, state->file_refs);
2587 state->file_refs = 0;
2588 }
9a56a232
JA
2589}
2590
2591/*
2592 * Get as many references to a file as we have IOs left in this submission,
2593 * assuming most submissions are for one file, or at least that each file
2594 * has more than one submission.
2595 */
8da11c19 2596static struct file *__io_file_get(struct io_submit_state *state, int fd)
9a56a232
JA
2597{
2598 if (!state)
2599 return fget(fd);
2600
6e1271e6 2601 if (state->file_refs) {
9a56a232 2602 if (state->fd == fd) {
6e1271e6 2603 state->file_refs--;
9a56a232
JA
2604 return state->file;
2605 }
02b23a9a 2606 io_state_file_put(state);
9a56a232
JA
2607 }
2608 state->file = fget_many(fd, state->ios_left);
6e1271e6 2609 if (unlikely(!state->file))
9a56a232
JA
2610 return NULL;
2611
2612 state->fd = fd;
6e1271e6 2613 state->file_refs = state->ios_left - 1;
9a56a232
JA
2614 return state->file;
2615}
2616
4503b767
JA
2617static bool io_bdev_nowait(struct block_device *bdev)
2618{
9ba0d0c8 2619 return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
4503b767
JA
2620}
2621
2b188cc1
JA
2622/*
2623 * If we tracked the file through the SCM inflight mechanism, we could support
2624 * any file. For now, just ensure that anything potentially problematic is done
2625 * inline.
2626 */
7b29f92d 2627static bool __io_file_supports_async(struct file *file, int rw)
2b188cc1
JA
2628{
2629 umode_t mode = file_inode(file)->i_mode;
2630
4503b767 2631 if (S_ISBLK(mode)) {
4e7b5671
CH
2632 if (IS_ENABLED(CONFIG_BLOCK) &&
2633 io_bdev_nowait(I_BDEV(file->f_mapping->host)))
4503b767
JA
2634 return true;
2635 return false;
2636 }
2637 if (S_ISCHR(mode) || S_ISSOCK(mode))
2b188cc1 2638 return true;
4503b767 2639 if (S_ISREG(mode)) {
4e7b5671
CH
2640 if (IS_ENABLED(CONFIG_BLOCK) &&
2641 io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
4503b767
JA
2642 file->f_op != &io_uring_fops)
2643 return true;
2644 return false;
2645 }
2b188cc1 2646
c5b85625
JA
2647 /* any ->read/write should understand O_NONBLOCK */
2648 if (file->f_flags & O_NONBLOCK)
2649 return true;
2650
af197f50
JA
2651 if (!(file->f_mode & FMODE_NOWAIT))
2652 return false;
2653
2654 if (rw == READ)
2655 return file->f_op->read_iter != NULL;
2656
2657 return file->f_op->write_iter != NULL;
2b188cc1
JA
2658}
2659
7b29f92d
JA
2660static bool io_file_supports_async(struct io_kiocb *req, int rw)
2661{
2662 if (rw == READ && (req->flags & REQ_F_ASYNC_READ))
2663 return true;
2664 else if (rw == WRITE && (req->flags & REQ_F_ASYNC_WRITE))
2665 return true;
2666
2667 return __io_file_supports_async(req->file, rw);
2668}
2669
a88fc400 2670static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
2b188cc1 2671{
def596e9 2672 struct io_ring_ctx *ctx = req->ctx;
9adbd45d 2673 struct kiocb *kiocb = &req->rw.kiocb;
75c668cd 2674 struct file *file = req->file;
09bb8394
JA
2675 unsigned ioprio;
2676 int ret;
2b188cc1 2677
7b29f92d 2678 if (!(req->flags & REQ_F_ISREG) && S_ISREG(file_inode(file)->i_mode))
491381ce
JA
2679 req->flags |= REQ_F_ISREG;
2680
2b188cc1 2681 kiocb->ki_pos = READ_ONCE(sqe->off);
75c668cd 2682 if (kiocb->ki_pos == -1 && !(file->f_mode & FMODE_STREAM)) {
ba04291e 2683 req->flags |= REQ_F_CUR_POS;
75c668cd 2684 kiocb->ki_pos = file->f_pos;
ba04291e 2685 }
2b188cc1 2686 kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
3e577dcd
PB
2687 kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
2688 ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
2689 if (unlikely(ret))
2690 return ret;
2b188cc1 2691
75c668cd
PB
2692 /* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
2693 if ((kiocb->ki_flags & IOCB_NOWAIT) || (file->f_flags & O_NONBLOCK))
2694 req->flags |= REQ_F_NOWAIT;
2695
2b188cc1
JA
2696 ioprio = READ_ONCE(sqe->ioprio);
2697 if (ioprio) {
2698 ret = ioprio_check_cap(ioprio);
2699 if (ret)
09bb8394 2700 return ret;
2b188cc1
JA
2701
2702 kiocb->ki_ioprio = ioprio;
2703 } else
2704 kiocb->ki_ioprio = get_current_ioprio();
2705
def596e9 2706 if (ctx->flags & IORING_SETUP_IOPOLL) {
def596e9
JA
2707 if (!(kiocb->ki_flags & IOCB_DIRECT) ||
2708 !kiocb->ki_filp->f_op->iopoll)
09bb8394 2709 return -EOPNOTSUPP;
2b188cc1 2710
def596e9
JA
2711 kiocb->ki_flags |= IOCB_HIPRI;
2712 kiocb->ki_complete = io_complete_rw_iopoll;
65a6543d 2713 req->iopoll_completed = 0;
def596e9 2714 } else {
09bb8394
JA
2715 if (kiocb->ki_flags & IOCB_HIPRI)
2716 return -EINVAL;
def596e9
JA
2717 kiocb->ki_complete = io_complete_rw;
2718 }
9adbd45d 2719
3529d8c2
JA
2720 req->rw.addr = READ_ONCE(sqe->addr);
2721 req->rw.len = READ_ONCE(sqe->len);
4f4eeba8 2722 req->buf_index = READ_ONCE(sqe->buf_index);
2b188cc1 2723 return 0;
2b188cc1
JA
2724}
2725
2726static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
2727{
2728 switch (ret) {
2729 case -EIOCBQUEUED:
2730 break;
2731 case -ERESTARTSYS:
2732 case -ERESTARTNOINTR:
2733 case -ERESTARTNOHAND:
2734 case -ERESTART_RESTARTBLOCK:
2735 /*
2736 * We can't just restart the syscall, since previously
2737 * submitted sqes may already be in progress. Just fail this
2738 * IO with EINTR.
2739 */
2740 ret = -EINTR;
df561f66 2741 fallthrough;
2b188cc1
JA
2742 default:
2743 kiocb->ki_complete(kiocb, ret, 0);
2744 }
2745}
2746
a1d7c393 2747static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
889fca73 2748 unsigned int issue_flags)
ba816ad6 2749{
ba04291e 2750 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
e8c2bc1f 2751 struct io_async_rw *io = req->async_data;
97284637 2752 bool check_reissue = kiocb->ki_complete == io_complete_rw;
ba04291e 2753
227c0c96 2754 /* add previously done IO, if any */
e8c2bc1f 2755 if (io && io->bytes_done > 0) {
227c0c96 2756 if (ret < 0)
e8c2bc1f 2757 ret = io->bytes_done;
227c0c96 2758 else
e8c2bc1f 2759 ret += io->bytes_done;
227c0c96
JA
2760 }
2761
ba04291e
JA
2762 if (req->flags & REQ_F_CUR_POS)
2763 req->file->f_pos = kiocb->ki_pos;
bcaec089 2764 if (ret >= 0 && kiocb->ki_complete == io_complete_rw)
889fca73 2765 __io_complete_rw(req, ret, 0, issue_flags);
ba816ad6
JA
2766 else
2767 io_rw_done(kiocb, ret);
97284637
PB
2768
2769 if (check_reissue && req->flags & REQ_F_REISSUE) {
2770 req->flags &= ~REQ_F_REISSUE;
8c130827
PB
2771 if (!io_resubmit_prep(req)) {
2772 req_ref_get(req);
2773 io_queue_async_work(req);
2774 } else {
97284637
PB
2775 int cflags = 0;
2776
2777 req_set_fail_links(req);
2778 if (req->flags & REQ_F_BUFFER_SELECTED)
2779 cflags = io_put_rw_kbuf(req);
2780 __io_req_complete(req, issue_flags, ret, cflags);
2781 }
2782 }
ba816ad6
JA
2783}
2784
847595de 2785static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
edafccee 2786{
9adbd45d
JA
2787 struct io_ring_ctx *ctx = req->ctx;
2788 size_t len = req->rw.len;
edafccee 2789 struct io_mapped_ubuf *imu;
4be1c615 2790 u16 index, buf_index = req->buf_index;
edafccee
JA
2791 size_t offset;
2792 u64 buf_addr;
2793
edafccee
JA
2794 if (unlikely(buf_index >= ctx->nr_user_bufs))
2795 return -EFAULT;
edafccee
JA
2796 index = array_index_nospec(buf_index, ctx->nr_user_bufs);
2797 imu = &ctx->user_bufs[index];
9adbd45d 2798 buf_addr = req->rw.addr;
edafccee
JA
2799
2800 /* overflow */
2801 if (buf_addr + len < buf_addr)
2802 return -EFAULT;
2803 /* not inside the mapped region */
2804 if (buf_addr < imu->ubuf || buf_addr + len > imu->ubuf + imu->len)
2805 return -EFAULT;
2806
2807 /*
2808 * May not be a start of buffer, set size appropriately
2809 * and advance us to the beginning.
2810 */
2811 offset = buf_addr - imu->ubuf;
2812 iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
bd11b3a3
JA
2813
2814 if (offset) {
2815 /*
2816 * Don't use iov_iter_advance() here, as it's really slow for
2817 * using the latter parts of a big fixed buffer - it iterates
2818 * over each segment manually. We can cheat a bit here, because
2819 * we know that:
2820 *
2821 * 1) it's a BVEC iter, we set it up
2822 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2823 * first and last bvec
2824 *
2825 * So just find our index, and adjust the iterator afterwards.
2826 * If the offset is within the first bvec (or the whole first
2827 * bvec, just use iov_iter_advance(). This makes it easier
2828 * since we can just skip the first segment, which may not
2829 * be PAGE_SIZE aligned.
2830 */
2831 const struct bio_vec *bvec = imu->bvec;
2832
2833 if (offset <= bvec->bv_len) {
2834 iov_iter_advance(iter, offset);
2835 } else {
2836 unsigned long seg_skip;
2837
2838 /* skip first vec */
2839 offset -= bvec->bv_len;
2840 seg_skip = 1 + (offset >> PAGE_SHIFT);
2841
2842 iter->bvec = bvec + seg_skip;
2843 iter->nr_segs -= seg_skip;
99c79f66 2844 iter->count -= bvec->bv_len + offset;
bd11b3a3 2845 iter->iov_offset = offset & ~PAGE_MASK;
bd11b3a3
JA
2846 }
2847 }
2848
847595de 2849 return 0;
edafccee
JA
2850}
2851
bcda7baa
JA
2852static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
2853{
2854 if (needs_lock)
2855 mutex_unlock(&ctx->uring_lock);
2856}
2857
2858static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
2859{
2860 /*
2861 * "Normal" inline submissions always hold the uring_lock, since we
2862 * grab it from the system call. Same is true for the SQPOLL offload.
2863 * The only exception is when we've detached the request and issue it
2864 * from an async worker thread, grab the lock for that case.
2865 */
2866 if (needs_lock)
2867 mutex_lock(&ctx->uring_lock);
2868}
2869
2870static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
2871 int bgid, struct io_buffer *kbuf,
2872 bool needs_lock)
2873{
2874 struct io_buffer *head;
2875
2876 if (req->flags & REQ_F_BUFFER_SELECTED)
2877 return kbuf;
2878
2879 io_ring_submit_lock(req->ctx, needs_lock);
2880
2881 lockdep_assert_held(&req->ctx->uring_lock);
2882
9e15c3a0 2883 head = xa_load(&req->ctx->io_buffers, bgid);
bcda7baa
JA
2884 if (head) {
2885 if (!list_empty(&head->list)) {
2886 kbuf = list_last_entry(&head->list, struct io_buffer,
2887 list);
2888 list_del(&kbuf->list);
2889 } else {
2890 kbuf = head;
9e15c3a0 2891 xa_erase(&req->ctx->io_buffers, bgid);
bcda7baa
JA
2892 }
2893 if (*len > kbuf->len)
2894 *len = kbuf->len;
2895 } else {
2896 kbuf = ERR_PTR(-ENOBUFS);
2897 }
2898
2899 io_ring_submit_unlock(req->ctx, needs_lock);
2900
2901 return kbuf;
2902}
2903
4d954c25
JA
2904static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
2905 bool needs_lock)
2906{
2907 struct io_buffer *kbuf;
4f4eeba8 2908 u16 bgid;
4d954c25
JA
2909
2910 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
4f4eeba8 2911 bgid = req->buf_index;
4d954c25
JA
2912 kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
2913 if (IS_ERR(kbuf))
2914 return kbuf;
2915 req->rw.addr = (u64) (unsigned long) kbuf;
2916 req->flags |= REQ_F_BUFFER_SELECTED;
2917 return u64_to_user_ptr(kbuf->addr);
2918}
2919
2920#ifdef CONFIG_COMPAT
2921static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
2922 bool needs_lock)
2923{
2924 struct compat_iovec __user *uiov;
2925 compat_ssize_t clen;
2926 void __user *buf;
2927 ssize_t len;
2928
2929 uiov = u64_to_user_ptr(req->rw.addr);
2930 if (!access_ok(uiov, sizeof(*uiov)))
2931 return -EFAULT;
2932 if (__get_user(clen, &uiov->iov_len))
2933 return -EFAULT;
2934 if (clen < 0)
2935 return -EINVAL;
2936
2937 len = clen;
2938 buf = io_rw_buffer_select(req, &len, needs_lock);
2939 if (IS_ERR(buf))
2940 return PTR_ERR(buf);
2941 iov[0].iov_base = buf;
2942 iov[0].iov_len = (compat_size_t) len;
2943 return 0;
2944}
2945#endif
2946
2947static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
2948 bool needs_lock)
2949{
2950 struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
2951 void __user *buf;
2952 ssize_t len;
2953
2954 if (copy_from_user(iov, uiov, sizeof(*uiov)))
2955 return -EFAULT;
2956
2957 len = iov[0].iov_len;
2958 if (len < 0)
2959 return -EINVAL;
2960 buf = io_rw_buffer_select(req, &len, needs_lock);
2961 if (IS_ERR(buf))
2962 return PTR_ERR(buf);
2963 iov[0].iov_base = buf;
2964 iov[0].iov_len = len;
2965 return 0;
2966}
2967
2968static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
2969 bool needs_lock)
2970{
dddb3e26
JA
2971 if (req->flags & REQ_F_BUFFER_SELECTED) {
2972 struct io_buffer *kbuf;
2973
2974 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
2975 iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
2976 iov[0].iov_len = kbuf->len;
4d954c25 2977 return 0;
dddb3e26 2978 }
dd201662 2979 if (req->rw.len != 1)
4d954c25
JA
2980 return -EINVAL;
2981
2982#ifdef CONFIG_COMPAT
2983 if (req->ctx->compat)
2984 return io_compat_import(req, iov, needs_lock);
2985#endif
2986
2987 return __io_iov_buffer_select(req, iov, needs_lock);
2988}
2989
847595de
PB
2990static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
2991 struct iov_iter *iter, bool needs_lock)
2b188cc1 2992{
9adbd45d
JA
2993 void __user *buf = u64_to_user_ptr(req->rw.addr);
2994 size_t sqe_len = req->rw.len;
847595de 2995 u8 opcode = req->opcode;
4d954c25 2996 ssize_t ret;
edafccee 2997
7d009165 2998 if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
edafccee 2999 *iovec = NULL;
9adbd45d 3000 return io_import_fixed(req, rw, iter);
edafccee 3001 }
2b188cc1 3002
bcda7baa 3003 /* buffer index only valid with fixed read/write, or buffer select */
4f4eeba8 3004 if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
9adbd45d
JA
3005 return -EINVAL;
3006
3a6820f2 3007 if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
bcda7baa 3008 if (req->flags & REQ_F_BUFFER_SELECT) {
4d954c25 3009 buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
867a23ea 3010 if (IS_ERR(buf))
4d954c25 3011 return PTR_ERR(buf);
3f9d6441 3012 req->rw.len = sqe_len;
bcda7baa
JA
3013 }
3014
3a6820f2
JA
3015 ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
3016 *iovec = NULL;
10fc72e4 3017 return ret;
3a6820f2
JA
3018 }
3019
4d954c25
JA
3020 if (req->flags & REQ_F_BUFFER_SELECT) {
3021 ret = io_iov_buffer_select(req, *iovec, needs_lock);
847595de
PB
3022 if (!ret)
3023 iov_iter_init(iter, rw, *iovec, 1, (*iovec)->iov_len);
4d954c25
JA
3024 *iovec = NULL;
3025 return ret;
3026 }
3027
89cd35c5
CH
3028 return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
3029 req->ctx->compat);
2b188cc1
JA
3030}
3031
0fef9483
JA
3032static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
3033{
5b09e37e 3034 return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
0fef9483
JA
3035}
3036
31b51510 3037/*
32960613
JA
3038 * For files that don't have ->read_iter() and ->write_iter(), handle them
3039 * by looping over ->read() or ->write() manually.
31b51510 3040 */
4017eb91 3041static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
32960613 3042{
4017eb91
JA
3043 struct kiocb *kiocb = &req->rw.kiocb;
3044 struct file *file = req->file;
32960613
JA
3045 ssize_t ret = 0;
3046
3047 /*
3048 * Don't support polled IO through this interface, and we can't
3049 * support non-blocking either. For the latter, this just causes
3050 * the kiocb to be handled from an async context.
3051 */
3052 if (kiocb->ki_flags & IOCB_HIPRI)
3053 return -EOPNOTSUPP;
3054 if (kiocb->ki_flags & IOCB_NOWAIT)
3055 return -EAGAIN;
3056
3057 while (iov_iter_count(iter)) {
311ae9e1 3058 struct iovec iovec;
32960613
JA
3059 ssize_t nr;
3060
311ae9e1
PB
3061 if (!iov_iter_is_bvec(iter)) {
3062 iovec = iov_iter_iovec(iter);
3063 } else {
4017eb91
JA
3064 iovec.iov_base = u64_to_user_ptr(req->rw.addr);
3065 iovec.iov_len = req->rw.len;
311ae9e1
PB
3066 }
3067
32960613
JA
3068 if (rw == READ) {
3069 nr = file->f_op->read(file, iovec.iov_base,
0fef9483 3070 iovec.iov_len, io_kiocb_ppos(kiocb));
32960613
JA
3071 } else {
3072 nr = file->f_op->write(file, iovec.iov_base,
0fef9483 3073 iovec.iov_len, io_kiocb_ppos(kiocb));
32960613
JA
3074 }
3075
3076 if (nr < 0) {
3077 if (!ret)
3078 ret = nr;
3079 break;
3080 }
3081 ret += nr;
3082 if (nr != iovec.iov_len)
3083 break;
4017eb91
JA
3084 req->rw.len -= nr;
3085 req->rw.addr += nr;
32960613
JA
3086 iov_iter_advance(iter, nr);
3087 }
3088
3089 return ret;
3090}
3091
ff6165b2
JA
3092static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
3093 const struct iovec *fast_iov, struct iov_iter *iter)
f67676d1 3094{
e8c2bc1f 3095 struct io_async_rw *rw = req->async_data;
b64e3444 3096
ff6165b2 3097 memcpy(&rw->iter, iter, sizeof(*iter));
afb87658 3098 rw->free_iovec = iovec;
227c0c96 3099 rw->bytes_done = 0;
ff6165b2 3100 /* can only be fixed buffers, no need to do anything */
9c3a205c 3101 if (iov_iter_is_bvec(iter))
ff6165b2 3102 return;
b64e3444 3103 if (!iovec) {
ff6165b2
JA
3104 unsigned iov_off = 0;
3105
3106 rw->iter.iov = rw->fast_iov;
3107 if (iter->iov != fast_iov) {
3108 iov_off = iter->iov - fast_iov;
3109 rw->iter.iov += iov_off;
3110 }
3111 if (rw->fast_iov != fast_iov)
3112 memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
45097dae 3113 sizeof(struct iovec) * iter->nr_segs);
99bc4c38
PB
3114 } else {
3115 req->flags |= REQ_F_NEED_CLEANUP;
f67676d1
JA
3116 }
3117}
3118
6cb78689 3119static inline int io_alloc_async_data(struct io_kiocb *req)
3d9932a8 3120{
e8c2bc1f
JA
3121 WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
3122 req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
3123 return req->async_data == NULL;
3d9932a8
XW
3124}
3125
ff6165b2
JA
3126static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
3127 const struct iovec *fast_iov,
227c0c96 3128 struct iov_iter *iter, bool force)
b7bb4f7d 3129{
26f0505a 3130 if (!force && !io_op_defs[req->opcode].needs_async_setup)
74566df3 3131 return 0;
e8c2bc1f 3132 if (!req->async_data) {
6cb78689 3133 if (io_alloc_async_data(req)) {
6bf985dc 3134 kfree(iovec);
5d204bcf 3135 return -ENOMEM;
6bf985dc 3136 }
b7bb4f7d 3137
ff6165b2 3138 io_req_map_rw(req, iovec, fast_iov, iter);
5d204bcf 3139 }
b7bb4f7d 3140 return 0;
f67676d1
JA
3141}
3142
73debe68 3143static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
c3e330a4 3144{
e8c2bc1f 3145 struct io_async_rw *iorw = req->async_data;
f4bff104 3146 struct iovec *iov = iorw->fast_iov;
847595de 3147 int ret;
c3e330a4 3148
2846c481 3149 ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
c3e330a4
PB
3150 if (unlikely(ret < 0))
3151 return ret;
3152
ab0b196c
PB
3153 iorw->bytes_done = 0;
3154 iorw->free_iovec = iov;
3155 if (iov)
3156 req->flags |= REQ_F_NEED_CLEANUP;
c3e330a4
PB
3157 return 0;
3158}
3159
73debe68 3160static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
f67676d1 3161{
3529d8c2
JA
3162 if (unlikely(!(req->file->f_mode & FMODE_READ)))
3163 return -EBADF;
93642ef8 3164 return io_prep_rw(req, sqe);
f67676d1
JA
3165}
3166
c1dd91d1
JA
3167/*
3168 * This is our waitqueue callback handler, registered through lock_page_async()
3169 * when we initially tried to do the IO with the iocb armed our waitqueue.
3170 * This gets called when the page is unlocked, and we generally expect that to
3171 * happen when the page IO is completed and the page is now uptodate. This will
3172 * queue a task_work based retry of the operation, attempting to copy the data
3173 * again. If the latter fails because the page was NOT uptodate, then we will
3174 * do a thread based blocking retry of the operation. That's the unexpected
3175 * slow path.
3176 */
bcf5a063
JA
3177static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
3178 int sync, void *arg)
3179{
3180 struct wait_page_queue *wpq;
3181 struct io_kiocb *req = wait->private;
bcf5a063 3182 struct wait_page_key *key = arg;
bcf5a063
JA
3183
3184 wpq = container_of(wait, struct wait_page_queue, wait);
3185
cdc8fcb4
LT
3186 if (!wake_page_match(wpq, key))
3187 return 0;
3188
c8d317aa 3189 req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
bcf5a063
JA
3190 list_del_init(&wait->entry);
3191
bcf5a063 3192 /* submit ref gets dropped, acquire a new one */
de9b4cca 3193 req_ref_get(req);
921b9054 3194 io_req_task_queue(req);
bcf5a063
JA
3195 return 1;
3196}
3197
c1dd91d1
JA
3198/*
3199 * This controls whether a given IO request should be armed for async page
3200 * based retry. If we return false here, the request is handed to the async
3201 * worker threads for retry. If we're doing buffered reads on a regular file,
3202 * we prepare a private wait_page_queue entry and retry the operation. This
3203 * will either succeed because the page is now uptodate and unlocked, or it
3204 * will register a callback when the page is unlocked at IO completion. Through
3205 * that callback, io_uring uses task_work to setup a retry of the operation.
3206 * That retry will attempt the buffered read again. The retry will generally
3207 * succeed, or in rare cases where it fails, we then fall back to using the
3208 * async worker threads for a blocking retry.
3209 */
227c0c96 3210static bool io_rw_should_retry(struct io_kiocb *req)
f67676d1 3211{
e8c2bc1f
JA
3212 struct io_async_rw *rw = req->async_data;
3213 struct wait_page_queue *wait = &rw->wpq;
bcf5a063 3214 struct kiocb *kiocb = &req->rw.kiocb;
f67676d1 3215
bcf5a063
JA
3216 /* never retry for NOWAIT, we just complete with -EAGAIN */
3217 if (req->flags & REQ_F_NOWAIT)
3218 return false;
f67676d1 3219
227c0c96 3220 /* Only for buffered IO */
3b2a4439 3221 if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
bcf5a063 3222 return false;
3b2a4439 3223
bcf5a063
JA
3224 /*
3225 * just use poll if we can, and don't attempt if the fs doesn't
3226 * support callback based unlocks
3227 */
3228 if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
3229 return false;
f67676d1 3230
3b2a4439
JA
3231 wait->wait.func = io_async_buf_func;
3232 wait->wait.private = req;
3233 wait->wait.flags = 0;
3234 INIT_LIST_HEAD(&wait->wait.entry);
3235 kiocb->ki_flags |= IOCB_WAITQ;
c8d317aa 3236 kiocb->ki_flags &= ~IOCB_NOWAIT;
3b2a4439 3237 kiocb->ki_waitq = wait;
3b2a4439 3238 return true;
bcf5a063
JA
3239}
3240
3241static int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
3242{
3243 if (req->file->f_op->read_iter)
3244 return call_read_iter(req->file, &req->rw.kiocb, iter);
2dd2111d 3245 else if (req->file->f_op->read)
4017eb91 3246 return loop_rw_iter(READ, req, iter);
2dd2111d
GH
3247 else
3248 return -EINVAL;
f67676d1
JA
3249}
3250
889fca73 3251static int io_read(struct io_kiocb *req, unsigned int issue_flags)
2b188cc1
JA
3252{
3253 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
9adbd45d 3254 struct kiocb *kiocb = &req->rw.kiocb;
ff6165b2 3255 struct iov_iter __iter, *iter = &__iter;
e8c2bc1f 3256 struct io_async_rw *rw = req->async_data;
227c0c96 3257 ssize_t io_size, ret, ret2;
45d189c6 3258 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
ff6165b2 3259
2846c481 3260 if (rw) {
e8c2bc1f 3261 iter = &rw->iter;
2846c481
PB
3262 iovec = NULL;
3263 } else {
3264 ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
3265 if (ret < 0)
3266 return ret;
3267 }
632546c4 3268 io_size = iov_iter_count(iter);
fa15bafb 3269 req->result = io_size;
2b188cc1 3270
fd6c2e4c
JA
3271 /* Ensure we clear previously set non-block flag */
3272 if (!force_nonblock)
29de5f6a 3273 kiocb->ki_flags &= ~IOCB_NOWAIT;
a88fc400
PB
3274 else
3275 kiocb->ki_flags |= IOCB_NOWAIT;
3276
24c74678 3277 /* If the file doesn't support async, just async punt */
7b29f92d 3278 if (force_nonblock && !io_file_supports_async(req, READ)) {
6713e7a6 3279 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
6bf985dc 3280 return ret ?: -EAGAIN;
6713e7a6 3281 }
9e645e11 3282
632546c4 3283 ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), io_size);
5ea5dd45
PB
3284 if (unlikely(ret)) {
3285 kfree(iovec);
3286 return ret;
3287 }
2b188cc1 3288
227c0c96 3289 ret = io_iter_do_read(req, iter);
32960613 3290
230d50d4 3291 if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
6ad7f233 3292 req->flags &= ~REQ_F_REISSUE;
eefdf30f
JA
3293 /* IOPOLL retry should happen for io-wq threads */
3294 if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
f91daf56 3295 goto done;
75c668cd
PB
3296 /* no retry on NONBLOCK nor RWF_NOWAIT */
3297 if (req->flags & REQ_F_NOWAIT)
355afaeb 3298 goto done;
84216315 3299 /* some cases will consume bytes even on error returns */
632546c4 3300 iov_iter_revert(iter, io_size - iov_iter_count(iter));
f38c7e3a 3301 ret = 0;
230d50d4
JA
3302 } else if (ret == -EIOCBQUEUED) {
3303 goto out_free;
7335e3bf 3304 } else if (ret <= 0 || ret == io_size || !force_nonblock ||
75c668cd 3305 (req->flags & REQ_F_NOWAIT) || !(req->flags & REQ_F_ISREG)) {
7335e3bf 3306 /* read all, failed, already did sync or don't want to retry */
00d23d51 3307 goto done;
227c0c96
JA
3308 }
3309
227c0c96 3310 ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
6bf985dc
PB
3311 if (ret2)
3312 return ret2;
3313
fe1cdd55 3314 iovec = NULL;
e8c2bc1f 3315 rw = req->async_data;
227c0c96 3316 /* now use our persistent iterator, if we aren't already */
e8c2bc1f 3317 iter = &rw->iter;
227c0c96 3318
b23df91b
PB
3319 do {
3320 io_size -= ret;
3321 rw->bytes_done += ret;
3322 /* if we can retry, do so with the callbacks armed */
3323 if (!io_rw_should_retry(req)) {
3324 kiocb->ki_flags &= ~IOCB_WAITQ;
3325 return -EAGAIN;
3326 }
3327
3328 /*
3329 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3330 * we get -EIOCBQUEUED, then we'll get a notification when the
3331 * desired page gets unlocked. We can also get a partial read
3332 * here, and if we do, then just retry at the new offset.
3333 */
3334 ret = io_iter_do_read(req, iter);
3335 if (ret == -EIOCBQUEUED)
3336 return 0;
227c0c96 3337 /* we got some bytes, but not all. retry. */
b5b0ecb7 3338 kiocb->ki_flags &= ~IOCB_WAITQ;
b23df91b 3339 } while (ret > 0 && ret < io_size);
227c0c96 3340done:
889fca73 3341 kiocb_done(kiocb, ret, issue_flags);
fe1cdd55
PB
3342out_free:
3343 /* it's faster to check here then delegate to kfree */
3344 if (iovec)
3345 kfree(iovec);
5ea5dd45 3346 return 0;
2b188cc1
JA
3347}
3348
73debe68 3349static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
f67676d1 3350{
3529d8c2
JA
3351 if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
3352 return -EBADF;
93642ef8 3353 return io_prep_rw(req, sqe);
f67676d1
JA
3354}
3355
889fca73 3356static int io_write(struct io_kiocb *req, unsigned int issue_flags)
2b188cc1
JA
3357{
3358 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
9adbd45d 3359 struct kiocb *kiocb = &req->rw.kiocb;
ff6165b2 3360 struct iov_iter __iter, *iter = &__iter;
e8c2bc1f 3361 struct io_async_rw *rw = req->async_data;
fa15bafb 3362 ssize_t ret, ret2, io_size;
45d189c6 3363 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
2b188cc1 3364
2846c481 3365 if (rw) {
e8c2bc1f 3366 iter = &rw->iter;
2846c481
PB
3367 iovec = NULL;
3368 } else {
3369 ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
3370 if (ret < 0)
3371 return ret;
3372 }
632546c4 3373 io_size = iov_iter_count(iter);
fa15bafb 3374 req->result = io_size;
2b188cc1 3375
fd6c2e4c
JA
3376 /* Ensure we clear previously set non-block flag */
3377 if (!force_nonblock)
a88fc400
PB
3378 kiocb->ki_flags &= ~IOCB_NOWAIT;
3379 else
3380 kiocb->ki_flags |= IOCB_NOWAIT;
fd6c2e4c 3381
24c74678 3382 /* If the file doesn't support async, just async punt */
7b29f92d 3383 if (force_nonblock && !io_file_supports_async(req, WRITE))
f67676d1 3384 goto copy_iov;
31b51510 3385
10d59345
JA
3386 /* file path doesn't support NOWAIT for non-direct_IO */
3387 if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
3388 (req->flags & REQ_F_ISREG))
f67676d1 3389 goto copy_iov;
31b51510 3390
632546c4 3391 ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), io_size);
fa15bafb
PB
3392 if (unlikely(ret))
3393 goto out_free;
4ed734b0 3394
fa15bafb
PB
3395 /*
3396 * Open-code file_start_write here to grab freeze protection,
3397 * which will be released by another thread in
3398 * io_complete_rw(). Fool lockdep by telling it the lock got
3399 * released so that it doesn't complain about the held lock when
3400 * we return to userspace.
3401 */
3402 if (req->flags & REQ_F_ISREG) {
8a3c84b6 3403 sb_start_write(file_inode(req->file)->i_sb);
fa15bafb
PB
3404 __sb_writers_release(file_inode(req->file)->i_sb,
3405 SB_FREEZE_WRITE);
3406 }
3407 kiocb->ki_flags |= IOCB_WRITE;
4ed734b0 3408
fa15bafb 3409 if (req->file->f_op->write_iter)
ff6165b2 3410 ret2 = call_write_iter(req->file, kiocb, iter);
2dd2111d 3411 else if (req->file->f_op->write)
4017eb91 3412 ret2 = loop_rw_iter(WRITE, req, iter);
2dd2111d
GH
3413 else
3414 ret2 = -EINVAL;
4ed734b0 3415
6ad7f233
PB
3416 if (req->flags & REQ_F_REISSUE) {
3417 req->flags &= ~REQ_F_REISSUE;
230d50d4 3418 ret2 = -EAGAIN;
6ad7f233 3419 }
230d50d4 3420
fa15bafb
PB
3421 /*
3422 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3423 * retry them without IOCB_NOWAIT.
3424 */
3425 if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
3426 ret2 = -EAGAIN;
75c668cd
PB
3427 /* no retry on NONBLOCK nor RWF_NOWAIT */
3428 if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
355afaeb 3429 goto done;
fa15bafb 3430 if (!force_nonblock || ret2 != -EAGAIN) {
eefdf30f
JA
3431 /* IOPOLL retry should happen for io-wq threads */
3432 if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
3433 goto copy_iov;
355afaeb 3434done:
889fca73 3435 kiocb_done(kiocb, ret2, issue_flags);
fa15bafb 3436 } else {
f67676d1 3437copy_iov:
84216315 3438 /* some cases will consume bytes even on error returns */
632546c4 3439 iov_iter_revert(iter, io_size - iov_iter_count(iter));
227c0c96 3440 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
6bf985dc 3441 return ret ?: -EAGAIN;
2b188cc1 3442 }
31b51510 3443out_free:
f261c168 3444 /* it's reportedly faster than delegating the null check to kfree() */
252917c3 3445 if (iovec)
6f2cc166 3446 kfree(iovec);
2b188cc1
JA
3447 return ret;
3448}
3449
80a261fd
JA
3450static int io_renameat_prep(struct io_kiocb *req,
3451 const struct io_uring_sqe *sqe)
3452{
3453 struct io_rename *ren = &req->rename;
3454 const char __user *oldf, *newf;
3455
3456 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3457 return -EBADF;
3458
3459 ren->old_dfd = READ_ONCE(sqe->fd);
3460 oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
3461 newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3462 ren->new_dfd = READ_ONCE(sqe->len);
3463 ren->flags = READ_ONCE(sqe->rename_flags);
3464
3465 ren->oldpath = getname(oldf);
3466 if (IS_ERR(ren->oldpath))
3467 return PTR_ERR(ren->oldpath);
3468
3469 ren->newpath = getname(newf);
3470 if (IS_ERR(ren->newpath)) {
3471 putname(ren->oldpath);
3472 return PTR_ERR(ren->newpath);
3473 }
3474
3475 req->flags |= REQ_F_NEED_CLEANUP;
3476 return 0;
3477}
3478
45d189c6 3479static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
80a261fd
JA
3480{
3481 struct io_rename *ren = &req->rename;
3482 int ret;
3483
45d189c6 3484 if (issue_flags & IO_URING_F_NONBLOCK)
80a261fd
JA
3485 return -EAGAIN;
3486
3487 ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
3488 ren->newpath, ren->flags);
3489
3490 req->flags &= ~REQ_F_NEED_CLEANUP;
3491 if (ret < 0)
3492 req_set_fail_links(req);
3493 io_req_complete(req, ret);
3494 return 0;
3495}
3496
14a1143b
JA
3497static int io_unlinkat_prep(struct io_kiocb *req,
3498 const struct io_uring_sqe *sqe)
3499{
3500 struct io_unlink *un = &req->unlink;
3501 const char __user *fname;
3502
3503 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3504 return -EBADF;
3505
3506 un->dfd = READ_ONCE(sqe->fd);
3507
3508 un->flags = READ_ONCE(sqe->unlink_flags);
3509 if (un->flags & ~AT_REMOVEDIR)
3510 return -EINVAL;
3511
3512 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
3513 un->filename = getname(fname);
3514 if (IS_ERR(un->filename))
3515 return PTR_ERR(un->filename);
3516
3517 req->flags |= REQ_F_NEED_CLEANUP;
3518 return 0;
3519}
3520
45d189c6 3521static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
14a1143b
JA
3522{
3523 struct io_unlink *un = &req->unlink;
3524 int ret;
3525
45d189c6 3526 if (issue_flags & IO_URING_F_NONBLOCK)
14a1143b
JA
3527 return -EAGAIN;
3528
3529 if (un->flags & AT_REMOVEDIR)
3530 ret = do_rmdir(un->dfd, un->filename);
3531 else
3532 ret = do_unlinkat(un->dfd, un->filename);
3533
3534 req->flags &= ~REQ_F_NEED_CLEANUP;
3535 if (ret < 0)
3536 req_set_fail_links(req);
3537 io_req_complete(req, ret);
3538 return 0;
3539}
3540
36f4fa68
JA
3541static int io_shutdown_prep(struct io_kiocb *req,
3542 const struct io_uring_sqe *sqe)
3543{
3544#if defined(CONFIG_NET)
3545 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3546 return -EINVAL;
3547 if (sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags ||
3548 sqe->buf_index)
3549 return -EINVAL;
3550
3551 req->shutdown.how = READ_ONCE(sqe->len);
3552 return 0;
3553#else
3554 return -EOPNOTSUPP;
3555#endif
3556}
3557
45d189c6 3558static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
36f4fa68
JA
3559{
3560#if defined(CONFIG_NET)
3561 struct socket *sock;
3562 int ret;
3563
45d189c6 3564 if (issue_flags & IO_URING_F_NONBLOCK)
36f4fa68
JA
3565 return -EAGAIN;
3566
48aba79b 3567 sock = sock_from_file(req->file);
36f4fa68 3568 if (unlikely(!sock))
48aba79b 3569 return -ENOTSOCK;
36f4fa68
JA
3570
3571 ret = __sys_shutdown_sock(sock, req->shutdown.how);
a146468d
JA
3572 if (ret < 0)
3573 req_set_fail_links(req);
36f4fa68
JA
3574 io_req_complete(req, ret);
3575 return 0;
3576#else
3577 return -EOPNOTSUPP;
3578#endif
3579}
3580
f2a8d5c7
PB
3581static int __io_splice_prep(struct io_kiocb *req,
3582 const struct io_uring_sqe *sqe)
7d67af2c
PB
3583{
3584 struct io_splice* sp = &req->splice;
3585 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
7d67af2c 3586
3232dd02
PB
3587 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3588 return -EINVAL;
7d67af2c
PB
3589
3590 sp->file_in = NULL;
7d67af2c
PB
3591 sp->len = READ_ONCE(sqe->len);
3592 sp->flags = READ_ONCE(sqe->splice_flags);
3593
3594 if (unlikely(sp->flags & ~valid_flags))
3595 return -EINVAL;
3596
8371adf5
PB
3597 sp->file_in = io_file_get(NULL, req, READ_ONCE(sqe->splice_fd_in),
3598 (sp->flags & SPLICE_F_FD_IN_FIXED));
3599 if (!sp->file_in)
3600 return -EBADF;
7d67af2c 3601 req->flags |= REQ_F_NEED_CLEANUP;
7d67af2c
PB
3602 return 0;
3603}
3604
f2a8d5c7
PB
3605static int io_tee_prep(struct io_kiocb *req,
3606 const struct io_uring_sqe *sqe)
3607{
3608 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
3609 return -EINVAL;
3610 return __io_splice_prep(req, sqe);
3611}
3612
45d189c6 3613static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
f2a8d5c7
PB
3614{
3615 struct io_splice *sp = &req->splice;
3616 struct file *in = sp->file_in;
3617 struct file *out = sp->file_out;
3618 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3619 long ret = 0;
3620
45d189c6 3621 if (issue_flags & IO_URING_F_NONBLOCK)
f2a8d5c7
PB
3622 return -EAGAIN;
3623 if (sp->len)
3624 ret = do_tee(in, out, sp->len, flags);
3625
e1d767f0
PB
3626 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
3627 io_put_file(in);
f2a8d5c7
PB
3628 req->flags &= ~REQ_F_NEED_CLEANUP;
3629
f2a8d5c7
PB
3630 if (ret != sp->len)
3631 req_set_fail_links(req);
e1e16097 3632 io_req_complete(req, ret);
f2a8d5c7
PB
3633 return 0;
3634}
3635
3636static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3637{
3638 struct io_splice* sp = &req->splice;
3639
3640 sp->off_in = READ_ONCE(sqe->splice_off_in);
3641 sp->off_out = READ_ONCE(sqe->off);
3642 return __io_splice_prep(req, sqe);
3643}
3644
45d189c6 3645static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
7d67af2c
PB
3646{
3647 struct io_splice *sp = &req->splice;
3648 struct file *in = sp->file_in;
3649 struct file *out = sp->file_out;
3650 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3651 loff_t *poff_in, *poff_out;
c9687426 3652 long ret = 0;
7d67af2c 3653
45d189c6 3654 if (issue_flags & IO_URING_F_NONBLOCK)
2fb3e822 3655 return -EAGAIN;
7d67af2c
PB
3656
3657 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
3658 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
c9687426 3659
948a7749 3660 if (sp->len)
c9687426 3661 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
7d67af2c 3662
e1d767f0
PB
3663 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
3664 io_put_file(in);
7d67af2c
PB
3665 req->flags &= ~REQ_F_NEED_CLEANUP;
3666
7d67af2c
PB
3667 if (ret != sp->len)
3668 req_set_fail_links(req);
e1e16097 3669 io_req_complete(req, ret);
7d67af2c
PB
3670 return 0;
3671}
3672
2b188cc1
JA
3673/*
3674 * IORING_OP_NOP just posts a completion event, nothing else.
3675 */
889fca73 3676static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
2b188cc1
JA
3677{
3678 struct io_ring_ctx *ctx = req->ctx;
2b188cc1 3679
def596e9
JA
3680 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
3681 return -EINVAL;
3682
889fca73 3683 __io_req_complete(req, issue_flags, 0, 0);
2b188cc1
JA
3684 return 0;
3685}
3686
1155c76a 3687static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
c992fe29 3688{
6b06314c 3689 struct io_ring_ctx *ctx = req->ctx;
c992fe29 3690
09bb8394
JA
3691 if (!req->file)
3692 return -EBADF;
c992fe29 3693
6b06314c 3694 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
def596e9 3695 return -EINVAL;
edafccee 3696 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
c992fe29
CH
3697 return -EINVAL;
3698
8ed8d3c3
JA
3699 req->sync.flags = READ_ONCE(sqe->fsync_flags);
3700 if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
3701 return -EINVAL;
3702
3703 req->sync.off = READ_ONCE(sqe->off);
3704 req->sync.len = READ_ONCE(sqe->len);
c992fe29
CH
3705 return 0;
3706}
3707
45d189c6 3708static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
8ed8d3c3 3709{
8ed8d3c3 3710 loff_t end = req->sync.off + req->sync.len;
8ed8d3c3
JA
3711 int ret;
3712
ac45abc0 3713 /* fsync always requires a blocking context */
45d189c6 3714 if (issue_flags & IO_URING_F_NONBLOCK)
ac45abc0
PB
3715 return -EAGAIN;
3716
9adbd45d 3717 ret = vfs_fsync_range(req->file, req->sync.off,
8ed8d3c3
JA
3718 end > 0 ? end : LLONG_MAX,
3719 req->sync.flags & IORING_FSYNC_DATASYNC);
3720 if (ret < 0)
3721 req_set_fail_links(req);
e1e16097 3722 io_req_complete(req, ret);
c992fe29
CH
3723 return 0;
3724}
3725
d63d1b5e
JA
3726static int io_fallocate_prep(struct io_kiocb *req,
3727 const struct io_uring_sqe *sqe)
3728{
3729 if (sqe->ioprio || sqe->buf_index || sqe->rw_flags)
3730 return -EINVAL;
3232dd02
PB
3731 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3732 return -EINVAL;
d63d1b5e
JA
3733
3734 req->sync.off = READ_ONCE(sqe->off);
3735 req->sync.len = READ_ONCE(sqe->addr);
3736 req->sync.mode = READ_ONCE(sqe->len);
3737 return 0;
3738}
3739
45d189c6 3740static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
5d17b4a4 3741{
ac45abc0
PB
3742 int ret;
3743
d63d1b5e 3744 /* fallocate always requiring blocking context */
45d189c6 3745 if (issue_flags & IO_URING_F_NONBLOCK)
5d17b4a4 3746 return -EAGAIN;
ac45abc0
PB
3747 ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
3748 req->sync.len);
ac45abc0
PB
3749 if (ret < 0)
3750 req_set_fail_links(req);
e1e16097 3751 io_req_complete(req, ret);
5d17b4a4
JA
3752 return 0;
3753}
3754
ec65fea5 3755static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
b7bb4f7d 3756{
f8748881 3757 const char __user *fname;
15b71abe 3758 int ret;
b7bb4f7d 3759
ec65fea5 3760 if (unlikely(sqe->ioprio || sqe->buf_index))
15b71abe 3761 return -EINVAL;
ec65fea5 3762 if (unlikely(req->flags & REQ_F_FIXED_FILE))
cf3040ca 3763 return -EBADF;
03b1230c 3764
ec65fea5
PB
3765 /* open.how should be already initialised */
3766 if (!(req->open.how.flags & O_PATH) && force_o_largefile())
08a1d26e 3767 req->open.how.flags |= O_LARGEFILE;
3529d8c2 3768
25e72d10
PB
3769 req->open.dfd = READ_ONCE(sqe->fd);
3770 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
f8748881 3771 req->open.filename = getname(fname);
15b71abe
JA
3772 if (IS_ERR(req->open.filename)) {
3773 ret = PTR_ERR(req->open.filename);
3774 req->open.filename = NULL;
3775 return ret;
3776 }
4022e7af 3777 req->open.nofile = rlimit(RLIMIT_NOFILE);
8fef80bf 3778 req->flags |= REQ_F_NEED_CLEANUP;
15b71abe 3779 return 0;
03b1230c
JA
3780}
3781
ec65fea5
PB
3782static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3783{
3784 u64 flags, mode;
3785
14587a46 3786 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4eb8dded 3787 return -EINVAL;
ec65fea5
PB
3788 mode = READ_ONCE(sqe->len);
3789 flags = READ_ONCE(sqe->open_flags);
3790 req->open.how = build_open_how(flags, mode);
3791 return __io_openat_prep(req, sqe);
3792}
3793
cebdb986 3794static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
aa1fa28f 3795{
cebdb986 3796 struct open_how __user *how;
cebdb986 3797 size_t len;
0fa03c62
JA
3798 int ret;
3799
14587a46 3800 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4eb8dded 3801 return -EINVAL;
cebdb986
JA
3802 how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3803 len = READ_ONCE(sqe->len);
cebdb986
JA
3804 if (len < OPEN_HOW_SIZE_VER0)
3805 return -EINVAL;
3529d8c2 3806
cebdb986
JA
3807 ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
3808 len);
3809 if (ret)
3810 return ret;
3529d8c2 3811
ec65fea5 3812 return __io_openat_prep(req, sqe);
cebdb986
JA
3813}
3814
45d189c6 3815static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
15b71abe
JA
3816{
3817 struct open_flags op;
15b71abe 3818 struct file *file;
3a81fd02
JA
3819 bool nonblock_set;
3820 bool resolve_nonblock;
15b71abe
JA
3821 int ret;
3822
cebdb986 3823 ret = build_open_flags(&req->open.how, &op);
15b71abe
JA
3824 if (ret)
3825 goto err;
3a81fd02
JA
3826 nonblock_set = op.open_flag & O_NONBLOCK;
3827 resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
45d189c6 3828 if (issue_flags & IO_URING_F_NONBLOCK) {
3a81fd02
JA
3829 /*
3830 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
3831 * it'll always -EAGAIN
3832 */
3833 if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
3834 return -EAGAIN;
3835 op.lookup_flags |= LOOKUP_CACHED;
3836 op.open_flag |= O_NONBLOCK;
3837 }
15b71abe 3838
4022e7af 3839 ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
15b71abe
JA
3840 if (ret < 0)
3841 goto err;
3842
3843 file = do_filp_open(req->open.dfd, req->open.filename, &op);
3a81fd02 3844 /* only retry if RESOLVE_CACHED wasn't already set by application */
45d189c6
PB
3845 if ((!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)) &&
3846 file == ERR_PTR(-EAGAIN)) {
944d1444 3847 /*
3a81fd02
JA
3848 * We could hang on to this 'fd', but seems like marginal
3849 * gain for something that is now known to be a slower path.
3850 * So just put it, and we'll get a new one when we retry.
944d1444 3851 */
3a81fd02
JA
3852 put_unused_fd(ret);
3853 return -EAGAIN;
3854 }
3855
15b71abe
JA
3856 if (IS_ERR(file)) {
3857 put_unused_fd(ret);
3858 ret = PTR_ERR(file);
3859 } else {
45d189c6 3860 if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
3a81fd02 3861 file->f_flags &= ~O_NONBLOCK;
15b71abe
JA
3862 fsnotify_open(file);
3863 fd_install(ret, file);
3864 }
3865err:
3866 putname(req->open.filename);
8fef80bf 3867 req->flags &= ~REQ_F_NEED_CLEANUP;
15b71abe
JA
3868 if (ret < 0)
3869 req_set_fail_links(req);
e1e16097 3870 io_req_complete(req, ret);
15b71abe
JA
3871 return 0;
3872}
3873
45d189c6 3874static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
cebdb986 3875{
e45cff58 3876 return io_openat2(req, issue_flags);
cebdb986
JA
3877}
3878
067524e9
JA
3879static int io_remove_buffers_prep(struct io_kiocb *req,
3880 const struct io_uring_sqe *sqe)
3881{
3882 struct io_provide_buf *p = &req->pbuf;
3883 u64 tmp;
3884
3885 if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off)
3886 return -EINVAL;
3887
3888 tmp = READ_ONCE(sqe->fd);
3889 if (!tmp || tmp > USHRT_MAX)
3890 return -EINVAL;
3891
3892 memset(p, 0, sizeof(*p));
3893 p->nbufs = tmp;
3894 p->bgid = READ_ONCE(sqe->buf_group);
3895 return 0;
3896}
3897
3898static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
3899 int bgid, unsigned nbufs)
3900{
3901 unsigned i = 0;
3902
3903 /* shouldn't happen */
3904 if (!nbufs)
3905 return 0;
3906
3907 /* the head kbuf is the list itself */
3908 while (!list_empty(&buf->list)) {
3909 struct io_buffer *nxt;
3910
3911 nxt = list_first_entry(&buf->list, struct io_buffer, list);
3912 list_del(&nxt->list);
3913 kfree(nxt);
3914 if (++i == nbufs)
3915 return i;
3916 }
3917 i++;
3918 kfree(buf);
9e15c3a0 3919 xa_erase(&ctx->io_buffers, bgid);
067524e9
JA
3920
3921 return i;
3922}
3923
889fca73 3924static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
067524e9
JA
3925{
3926 struct io_provide_buf *p = &req->pbuf;
3927 struct io_ring_ctx *ctx = req->ctx;
3928 struct io_buffer *head;
3929 int ret = 0;
45d189c6 3930 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
067524e9
JA
3931
3932 io_ring_submit_lock(ctx, !force_nonblock);
3933
3934 lockdep_assert_held(&ctx->uring_lock);
3935
3936 ret = -ENOENT;
9e15c3a0 3937 head = xa_load(&ctx->io_buffers, p->bgid);
067524e9
JA
3938 if (head)
3939 ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
067524e9
JA
3940 if (ret < 0)
3941 req_set_fail_links(req);
067524e9 3942
9fb8cb49
PB
3943 /* complete before unlock, IOPOLL may need the lock */
3944 __io_req_complete(req, issue_flags, ret, 0);
3945 io_ring_submit_unlock(ctx, !force_nonblock);
067524e9
JA
3946 return 0;
3947}
3948
ddf0322d
JA
3949static int io_provide_buffers_prep(struct io_kiocb *req,
3950 const struct io_uring_sqe *sqe)
3951{
d81269fe 3952 unsigned long size;
ddf0322d
JA
3953 struct io_provide_buf *p = &req->pbuf;
3954 u64 tmp;
3955
3956 if (sqe->ioprio || sqe->rw_flags)
3957 return -EINVAL;
3958
3959 tmp = READ_ONCE(sqe->fd);
3960 if (!tmp || tmp > USHRT_MAX)
3961 return -E2BIG;
3962 p->nbufs = tmp;
3963 p->addr = READ_ONCE(sqe->addr);
3964 p->len = READ_ONCE(sqe->len);
3965
d81269fe
PB
3966 size = (unsigned long)p->len * p->nbufs;
3967 if (!access_ok(u64_to_user_ptr(p->addr), size))
ddf0322d
JA
3968 return -EFAULT;
3969
3970 p->bgid = READ_ONCE(sqe->buf_group);
3971 tmp = READ_ONCE(sqe->off);
3972 if (tmp > USHRT_MAX)
3973 return -E2BIG;
3974 p->bid = tmp;
3975 return 0;
3976}
3977
3978static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
3979{
3980 struct io_buffer *buf;
3981 u64 addr = pbuf->addr;
3982 int i, bid = pbuf->bid;
3983
3984 for (i = 0; i < pbuf->nbufs; i++) {
3985 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
3986 if (!buf)
3987 break;
3988
3989 buf->addr = addr;
3990 buf->len = pbuf->len;
3991 buf->bid = bid;
3992 addr += pbuf->len;
3993 bid++;
3994 if (!*head) {
3995 INIT_LIST_HEAD(&buf->list);
3996 *head = buf;
3997 } else {
3998 list_add_tail(&buf->list, &(*head)->list);
3999 }
4000 }
4001
4002 return i ? i : -ENOMEM;
4003}
4004
889fca73 4005static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
ddf0322d
JA
4006{
4007 struct io_provide_buf *p = &req->pbuf;
4008 struct io_ring_ctx *ctx = req->ctx;
4009 struct io_buffer *head, *list;
4010 int ret = 0;
45d189c6 4011 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
ddf0322d
JA
4012
4013 io_ring_submit_lock(ctx, !force_nonblock);
4014
4015 lockdep_assert_held(&ctx->uring_lock);
4016
9e15c3a0 4017 list = head = xa_load(&ctx->io_buffers, p->bgid);
ddf0322d
JA
4018
4019 ret = io_add_buffers(p, &head);
9e15c3a0
JA
4020 if (ret >= 0 && !list) {
4021 ret = xa_insert(&ctx->io_buffers, p->bgid, head, GFP_KERNEL);
4022 if (ret < 0)
067524e9 4023 __io_remove_buffers(ctx, head, p->bgid, -1U);
ddf0322d 4024 }
ddf0322d
JA
4025 if (ret < 0)
4026 req_set_fail_links(req);
9fb8cb49
PB
4027 /* complete before unlock, IOPOLL may need the lock */
4028 __io_req_complete(req, issue_flags, ret, 0);
4029 io_ring_submit_unlock(ctx, !force_nonblock);
ddf0322d 4030 return 0;
cebdb986
JA
4031}
4032
3e4827b0
JA
4033static int io_epoll_ctl_prep(struct io_kiocb *req,
4034 const struct io_uring_sqe *sqe)
4035{
4036#if defined(CONFIG_EPOLL)
4037 if (sqe->ioprio || sqe->buf_index)
4038 return -EINVAL;
6ca56f84 4039 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL)))
3232dd02 4040 return -EINVAL;
3e4827b0
JA
4041
4042 req->epoll.epfd = READ_ONCE(sqe->fd);
4043 req->epoll.op = READ_ONCE(sqe->len);
4044 req->epoll.fd = READ_ONCE(sqe->off);
4045
4046 if (ep_op_has_event(req->epoll.op)) {
4047 struct epoll_event __user *ev;
4048
4049 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
4050 if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
4051 return -EFAULT;
4052 }
4053
4054 return 0;
4055#else
4056 return -EOPNOTSUPP;
4057#endif
4058}
4059
889fca73 4060static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
3e4827b0
JA
4061{
4062#if defined(CONFIG_EPOLL)
4063 struct io_epoll *ie = &req->epoll;
4064 int ret;
45d189c6 4065 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3e4827b0
JA
4066
4067 ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
4068 if (force_nonblock && ret == -EAGAIN)
4069 return -EAGAIN;
4070
4071 if (ret < 0)
4072 req_set_fail_links(req);
889fca73 4073 __io_req_complete(req, issue_flags, ret, 0);
3e4827b0
JA
4074 return 0;
4075#else
4076 return -EOPNOTSUPP;
4077#endif
4078}
4079
c1ca757b
JA
4080static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4081{
4082#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4083 if (sqe->ioprio || sqe->buf_index || sqe->off)
4084 return -EINVAL;
3232dd02
PB
4085 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4086 return -EINVAL;
c1ca757b
JA
4087
4088 req->madvise.addr = READ_ONCE(sqe->addr);
4089 req->madvise.len = READ_ONCE(sqe->len);
4090 req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
4091 return 0;
4092#else
4093 return -EOPNOTSUPP;
4094#endif
4095}
4096
45d189c6 4097static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
c1ca757b
JA
4098{
4099#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4100 struct io_madvise *ma = &req->madvise;
4101 int ret;
4102
45d189c6 4103 if (issue_flags & IO_URING_F_NONBLOCK)
c1ca757b
JA
4104 return -EAGAIN;
4105
0726b01e 4106 ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
c1ca757b
JA
4107 if (ret < 0)
4108 req_set_fail_links(req);
e1e16097 4109 io_req_complete(req, ret);
c1ca757b
JA
4110 return 0;
4111#else
4112 return -EOPNOTSUPP;
4113#endif
4114}
4115
4840e418
JA
4116static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4117{
4118 if (sqe->ioprio || sqe->buf_index || sqe->addr)
4119 return -EINVAL;
3232dd02
PB
4120 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4121 return -EINVAL;
4840e418
JA
4122
4123 req->fadvise.offset = READ_ONCE(sqe->off);
4124 req->fadvise.len = READ_ONCE(sqe->len);
4125 req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
4126 return 0;
4127}
4128
45d189c6 4129static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
4840e418
JA
4130{
4131 struct io_fadvise *fa = &req->fadvise;
4132 int ret;
4133
45d189c6 4134 if (issue_flags & IO_URING_F_NONBLOCK) {
3e69426d
JA
4135 switch (fa->advice) {
4136 case POSIX_FADV_NORMAL:
4137 case POSIX_FADV_RANDOM:
4138 case POSIX_FADV_SEQUENTIAL:
4139 break;
4140 default:
4141 return -EAGAIN;
4142 }
4143 }
4840e418
JA
4144
4145 ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
4146 if (ret < 0)
4147 req_set_fail_links(req);
e1e16097 4148 io_req_complete(req, ret);
4840e418
JA
4149 return 0;
4150}
4151
eddc7ef5
JA
4152static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4153{
6ca56f84 4154 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL)))
3232dd02 4155 return -EINVAL;
eddc7ef5
JA
4156 if (sqe->ioprio || sqe->buf_index)
4157 return -EINVAL;
9c280f90 4158 if (req->flags & REQ_F_FIXED_FILE)
cf3040ca 4159 return -EBADF;
eddc7ef5 4160
1d9e1288
BM
4161 req->statx.dfd = READ_ONCE(sqe->fd);
4162 req->statx.mask = READ_ONCE(sqe->len);
e62753e4 4163 req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
1d9e1288
BM
4164 req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4165 req->statx.flags = READ_ONCE(sqe->statx_flags);
eddc7ef5
JA
4166
4167 return 0;
4168}
4169
45d189c6 4170static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
eddc7ef5 4171{
1d9e1288 4172 struct io_statx *ctx = &req->statx;
eddc7ef5
JA
4173 int ret;
4174
59d70013 4175 if (issue_flags & IO_URING_F_NONBLOCK)
eddc7ef5
JA
4176 return -EAGAIN;
4177
e62753e4
BM
4178 ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
4179 ctx->buffer);
eddc7ef5 4180
eddc7ef5
JA
4181 if (ret < 0)
4182 req_set_fail_links(req);
e1e16097 4183 io_req_complete(req, ret);
eddc7ef5
JA
4184 return 0;
4185}
4186
b5dba59e
JA
4187static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4188{
14587a46 4189 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3232dd02 4190 return -EINVAL;
b5dba59e
JA
4191 if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
4192 sqe->rw_flags || sqe->buf_index)
4193 return -EINVAL;
9c280f90 4194 if (req->flags & REQ_F_FIXED_FILE)
cf3040ca 4195 return -EBADF;
b5dba59e
JA
4196
4197 req->close.fd = READ_ONCE(sqe->fd);
b5dba59e 4198 return 0;
b5dba59e
JA
4199}
4200
889fca73 4201static int io_close(struct io_kiocb *req, unsigned int issue_flags)
b5dba59e 4202{
9eac1904 4203 struct files_struct *files = current->files;
3af73b28 4204 struct io_close *close = &req->close;
9eac1904
JA
4205 struct fdtable *fdt;
4206 struct file *file;
b5dba59e
JA
4207 int ret;
4208
9eac1904
JA
4209 file = NULL;
4210 ret = -EBADF;
4211 spin_lock(&files->file_lock);
4212 fdt = files_fdtable(files);
4213 if (close->fd >= fdt->max_fds) {
4214 spin_unlock(&files->file_lock);
4215 goto err;
4216 }
4217 file = fdt->fd[close->fd];
4218 if (!file) {
4219 spin_unlock(&files->file_lock);
4220 goto err;
4221 }
4222
4223 if (file->f_op == &io_uring_fops) {
4224 spin_unlock(&files->file_lock);
4225 file = NULL;
4226 goto err;
3af73b28 4227 }
b5dba59e
JA
4228
4229 /* if the file has a flush method, be safe and punt to async */
45d189c6 4230 if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
9eac1904 4231 spin_unlock(&files->file_lock);
0bf0eefd 4232 return -EAGAIN;
a2100672 4233 }
b5dba59e 4234
9eac1904
JA
4235 ret = __close_fd_get_file(close->fd, &file);
4236 spin_unlock(&files->file_lock);
4237 if (ret < 0) {
4238 if (ret == -ENOENT)
4239 ret = -EBADF;
4240 goto err;
4241 }
4242
3af73b28 4243 /* No ->flush() or already async, safely close from here */
9eac1904
JA
4244 ret = filp_close(file, current->files);
4245err:
3af73b28
PB
4246 if (ret < 0)
4247 req_set_fail_links(req);
9eac1904
JA
4248 if (file)
4249 fput(file);
889fca73 4250 __io_req_complete(req, issue_flags, ret, 0);
1a417f4e 4251 return 0;
b5dba59e
JA
4252}
4253
1155c76a 4254static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5d17b4a4
JA
4255{
4256 struct io_ring_ctx *ctx = req->ctx;
5d17b4a4 4257
5d17b4a4
JA
4258 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
4259 return -EINVAL;
4260 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
4261 return -EINVAL;
4262
8ed8d3c3
JA
4263 req->sync.off = READ_ONCE(sqe->off);
4264 req->sync.len = READ_ONCE(sqe->len);
4265 req->sync.flags = READ_ONCE(sqe->sync_range_flags);
8ed8d3c3
JA
4266 return 0;
4267}
4268
45d189c6 4269static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
8ed8d3c3 4270{
8ed8d3c3
JA
4271 int ret;
4272
ac45abc0 4273 /* sync_file_range always requires a blocking context */
45d189c6 4274 if (issue_flags & IO_URING_F_NONBLOCK)
ac45abc0
PB
4275 return -EAGAIN;
4276
9adbd45d 4277 ret = sync_file_range(req->file, req->sync.off, req->sync.len,
8ed8d3c3
JA
4278 req->sync.flags);
4279 if (ret < 0)
4280 req_set_fail_links(req);
e1e16097 4281 io_req_complete(req, ret);
5d17b4a4
JA
4282 return 0;
4283}
4284
469956e8 4285#if defined(CONFIG_NET)
02d27d89
PB
4286static int io_setup_async_msg(struct io_kiocb *req,
4287 struct io_async_msghdr *kmsg)
4288{
e8c2bc1f
JA
4289 struct io_async_msghdr *async_msg = req->async_data;
4290
4291 if (async_msg)
02d27d89 4292 return -EAGAIN;
e8c2bc1f 4293 if (io_alloc_async_data(req)) {
257e84a5 4294 kfree(kmsg->free_iov);
02d27d89
PB
4295 return -ENOMEM;
4296 }
e8c2bc1f 4297 async_msg = req->async_data;
02d27d89 4298 req->flags |= REQ_F_NEED_CLEANUP;
e8c2bc1f 4299 memcpy(async_msg, kmsg, sizeof(*kmsg));
2a780802 4300 async_msg->msg.msg_name = &async_msg->addr;
257e84a5
PB
4301 /* if were using fast_iov, set it to the new one */
4302 if (!async_msg->free_iov)
4303 async_msg->msg.msg_iter.iov = async_msg->fast_iov;
4304
02d27d89
PB
4305 return -EAGAIN;
4306}
4307
2ae523ed
PB
4308static int io_sendmsg_copy_hdr(struct io_kiocb *req,
4309 struct io_async_msghdr *iomsg)
4310{
2ae523ed 4311 iomsg->msg.msg_name = &iomsg->addr;
257e84a5 4312 iomsg->free_iov = iomsg->fast_iov;
2ae523ed 4313 return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
257e84a5 4314 req->sr_msg.msg_flags, &iomsg->free_iov);
2ae523ed
PB
4315}
4316
93642ef8
PB
4317static int io_sendmsg_prep_async(struct io_kiocb *req)
4318{
4319 int ret;
4320
93642ef8
PB
4321 ret = io_sendmsg_copy_hdr(req, req->async_data);
4322 if (!ret)
4323 req->flags |= REQ_F_NEED_CLEANUP;
4324 return ret;
4325}
4326
3529d8c2 4327static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
03b1230c 4328{
e47293fd 4329 struct io_sr_msg *sr = &req->sr_msg;
03b1230c 4330
d2b6f48b
PB
4331 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4332 return -EINVAL;
4333
e47293fd 4334 sr->msg_flags = READ_ONCE(sqe->msg_flags);
270a5940 4335 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
fddaface 4336 sr->len = READ_ONCE(sqe->len);
3529d8c2 4337
d8768362
JA
4338#ifdef CONFIG_COMPAT
4339 if (req->ctx->compat)
4340 sr->msg_flags |= MSG_CMSG_COMPAT;
4341#endif
93642ef8 4342 return 0;
03b1230c
JA
4343}
4344
889fca73 4345static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
aa1fa28f 4346{
6b754c8b 4347 struct io_async_msghdr iomsg, *kmsg;
0fa03c62 4348 struct socket *sock;
7a7cacba 4349 unsigned flags;
0031275d 4350 int min_ret = 0;
0fa03c62
JA
4351 int ret;
4352
dba4a925 4353 sock = sock_from_file(req->file);
7a7cacba 4354 if (unlikely(!sock))
dba4a925 4355 return -ENOTSOCK;
3529d8c2 4356
257e84a5
PB
4357 kmsg = req->async_data;
4358 if (!kmsg) {
7a7cacba
PB
4359 ret = io_sendmsg_copy_hdr(req, &iomsg);
4360 if (ret)
4361 return ret;
4362 kmsg = &iomsg;
0fa03c62 4363 }
0fa03c62 4364
76cd979f 4365 flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
7a7cacba
PB
4366 if (flags & MSG_DONTWAIT)
4367 req->flags |= REQ_F_NOWAIT;
45d189c6 4368 else if (issue_flags & IO_URING_F_NONBLOCK)
7a7cacba 4369 flags |= MSG_DONTWAIT;
e47293fd 4370
0031275d
SM
4371 if (flags & MSG_WAITALL)
4372 min_ret = iov_iter_count(&kmsg->msg.msg_iter);
4373
7a7cacba 4374 ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
45d189c6 4375 if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
7a7cacba
PB
4376 return io_setup_async_msg(req, kmsg);
4377 if (ret == -ERESTARTSYS)
4378 ret = -EINTR;
0fa03c62 4379
257e84a5
PB
4380 /* fast path, check for non-NULL to avoid function call */
4381 if (kmsg->free_iov)
4382 kfree(kmsg->free_iov);
99bc4c38 4383 req->flags &= ~REQ_F_NEED_CLEANUP;
0031275d 4384 if (ret < min_ret)
4e88d6e7 4385 req_set_fail_links(req);
889fca73 4386 __io_req_complete(req, issue_flags, ret, 0);
5d17b4a4 4387 return 0;
03b1230c 4388}
aa1fa28f 4389
889fca73 4390static int io_send(struct io_kiocb *req, unsigned int issue_flags)
fddaface 4391{
7a7cacba
PB
4392 struct io_sr_msg *sr = &req->sr_msg;
4393 struct msghdr msg;
4394 struct iovec iov;
fddaface 4395 struct socket *sock;
7a7cacba 4396 unsigned flags;
0031275d 4397 int min_ret = 0;
fddaface
JA
4398 int ret;
4399
dba4a925 4400 sock = sock_from_file(req->file);
7a7cacba 4401 if (unlikely(!sock))
dba4a925 4402 return -ENOTSOCK;
fddaface 4403
7a7cacba
PB
4404 ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
4405 if (unlikely(ret))
14db8411 4406 return ret;
fddaface 4407
7a7cacba
PB
4408 msg.msg_name = NULL;
4409 msg.msg_control = NULL;
4410 msg.msg_controllen = 0;
4411 msg.msg_namelen = 0;
fddaface 4412
76cd979f 4413 flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
7a7cacba
PB
4414 if (flags & MSG_DONTWAIT)
4415 req->flags |= REQ_F_NOWAIT;
45d189c6 4416 else if (issue_flags & IO_URING_F_NONBLOCK)
7a7cacba 4417 flags |= MSG_DONTWAIT;
fddaface 4418
0031275d
SM
4419 if (flags & MSG_WAITALL)
4420 min_ret = iov_iter_count(&msg.msg_iter);
4421
7a7cacba
PB
4422 msg.msg_flags = flags;
4423 ret = sock_sendmsg(sock, &msg);
45d189c6 4424 if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
7a7cacba
PB
4425 return -EAGAIN;
4426 if (ret == -ERESTARTSYS)
4427 ret = -EINTR;
fddaface 4428
0031275d 4429 if (ret < min_ret)
fddaface 4430 req_set_fail_links(req);
889fca73 4431 __io_req_complete(req, issue_flags, ret, 0);
fddaface 4432 return 0;
fddaface
JA
4433}
4434
1400e697
PB
4435static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
4436 struct io_async_msghdr *iomsg)
52de1fe1
JA
4437{
4438 struct io_sr_msg *sr = &req->sr_msg;
4439 struct iovec __user *uiov;
4440 size_t iov_len;
4441 int ret;
4442
1400e697
PB
4443 ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
4444 &iomsg->uaddr, &uiov, &iov_len);
52de1fe1
JA
4445 if (ret)
4446 return ret;
4447
4448 if (req->flags & REQ_F_BUFFER_SELECT) {
4449 if (iov_len > 1)
4450 return -EINVAL;
5476dfed 4451 if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
52de1fe1 4452 return -EFAULT;
5476dfed 4453 sr->len = iomsg->fast_iov[0].iov_len;
257e84a5 4454 iomsg->free_iov = NULL;
52de1fe1 4455 } else {
257e84a5 4456 iomsg->free_iov = iomsg->fast_iov;
89cd35c5 4457 ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
257e84a5 4458 &iomsg->free_iov, &iomsg->msg.msg_iter,
89cd35c5 4459 false);
52de1fe1
JA
4460 if (ret > 0)
4461 ret = 0;
4462 }
4463
4464 return ret;
4465}
4466
4467#ifdef CONFIG_COMPAT
4468static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
1400e697 4469 struct io_async_msghdr *iomsg)
52de1fe1
JA
4470{
4471 struct compat_msghdr __user *msg_compat;
4472 struct io_sr_msg *sr = &req->sr_msg;
4473 struct compat_iovec __user *uiov;
4474 compat_uptr_t ptr;
4475 compat_size_t len;
4476 int ret;
4477
270a5940 4478 msg_compat = (struct compat_msghdr __user *) sr->umsg;
1400e697 4479 ret = __get_compat_msghdr(&iomsg->msg, msg_compat, &iomsg->uaddr,
52de1fe1
JA
4480 &ptr, &len);
4481 if (ret)
4482 return ret;
4483
4484 uiov = compat_ptr(ptr);
4485 if (req->flags & REQ_F_BUFFER_SELECT) {
4486 compat_ssize_t clen;
4487
4488 if (len > 1)
4489 return -EINVAL;
4490 if (!access_ok(uiov, sizeof(*uiov)))
4491 return -EFAULT;
4492 if (__get_user(clen, &uiov->iov_len))
4493 return -EFAULT;
4494 if (clen < 0)
4495 return -EINVAL;
2d280bc8 4496 sr->len = clen;
257e84a5 4497 iomsg->free_iov = NULL;
52de1fe1 4498 } else {
257e84a5 4499 iomsg->free_iov = iomsg->fast_iov;
89cd35c5 4500 ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
257e84a5 4501 UIO_FASTIOV, &iomsg->free_iov,
89cd35c5 4502 &iomsg->msg.msg_iter, true);
52de1fe1
JA
4503 if (ret < 0)
4504 return ret;
4505 }
4506
4507 return 0;
4508}
4509#endif
4510
1400e697
PB
4511static int io_recvmsg_copy_hdr(struct io_kiocb *req,
4512 struct io_async_msghdr *iomsg)
52de1fe1 4513{
1400e697 4514 iomsg->msg.msg_name = &iomsg->addr;
52de1fe1
JA
4515
4516#ifdef CONFIG_COMPAT
4517 if (req->ctx->compat)
1400e697 4518 return __io_compat_recvmsg_copy_hdr(req, iomsg);
fddaface 4519#endif
52de1fe1 4520
1400e697 4521 return __io_recvmsg_copy_hdr(req, iomsg);
52de1fe1
JA
4522}
4523
bcda7baa 4524static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
7fbb1b54 4525 bool needs_lock)
bcda7baa
JA
4526{
4527 struct io_sr_msg *sr = &req->sr_msg;
4528 struct io_buffer *kbuf;
4529
bcda7baa
JA
4530 kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
4531 if (IS_ERR(kbuf))
4532 return kbuf;
4533
4534 sr->kbuf = kbuf;
4535 req->flags |= REQ_F_BUFFER_SELECTED;
bcda7baa 4536 return kbuf;
fddaface
JA
4537}
4538
7fbb1b54
PB
4539static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
4540{
4541 return io_put_kbuf(req, req->sr_msg.kbuf);
4542}
4543
93642ef8 4544static int io_recvmsg_prep_async(struct io_kiocb *req)
aa1fa28f 4545{
99bc4c38 4546 int ret;
3529d8c2 4547
93642ef8
PB
4548 ret = io_recvmsg_copy_hdr(req, req->async_data);
4549 if (!ret)
4550 req->flags |= REQ_F_NEED_CLEANUP;
4551 return ret;
4552}
4553
4554static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4555{
4556 struct io_sr_msg *sr = &req->sr_msg;
4557
d2b6f48b
PB
4558 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4559 return -EINVAL;
4560
3529d8c2 4561 sr->msg_flags = READ_ONCE(sqe->msg_flags);
270a5940 4562 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
0b7b21e4 4563 sr->len = READ_ONCE(sqe->len);
bcda7baa 4564 sr->bgid = READ_ONCE(sqe->buf_group);
06b76d44 4565
d8768362
JA
4566#ifdef CONFIG_COMPAT
4567 if (req->ctx->compat)
4568 sr->msg_flags |= MSG_CMSG_COMPAT;
4569#endif
93642ef8 4570 return 0;
aa1fa28f
JA
4571}
4572
889fca73 4573static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
aa1fa28f 4574{
6b754c8b 4575 struct io_async_msghdr iomsg, *kmsg;
03b1230c 4576 struct socket *sock;
7fbb1b54 4577 struct io_buffer *kbuf;
7a7cacba 4578 unsigned flags;
0031275d 4579 int min_ret = 0;
52de1fe1 4580 int ret, cflags = 0;
45d189c6 4581 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
03b1230c 4582
dba4a925 4583 sock = sock_from_file(req->file);
7a7cacba 4584 if (unlikely(!sock))
dba4a925 4585 return -ENOTSOCK;
3529d8c2 4586
257e84a5
PB
4587 kmsg = req->async_data;
4588 if (!kmsg) {
7a7cacba
PB
4589 ret = io_recvmsg_copy_hdr(req, &iomsg);
4590 if (ret)
681fda8d 4591 return ret;
7a7cacba
PB
4592 kmsg = &iomsg;
4593 }
03b1230c 4594
bc02ef33 4595 if (req->flags & REQ_F_BUFFER_SELECT) {
7fbb1b54 4596 kbuf = io_recv_buffer_select(req, !force_nonblock);
bc02ef33 4597 if (IS_ERR(kbuf))
52de1fe1 4598 return PTR_ERR(kbuf);
7a7cacba 4599 kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
5476dfed
PB
4600 kmsg->fast_iov[0].iov_len = req->sr_msg.len;
4601 iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov,
7a7cacba
PB
4602 1, req->sr_msg.len);
4603 }
52de1fe1 4604
76cd979f 4605 flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
7a7cacba
PB
4606 if (flags & MSG_DONTWAIT)
4607 req->flags |= REQ_F_NOWAIT;
4608 else if (force_nonblock)
4609 flags |= MSG_DONTWAIT;
e47293fd 4610
0031275d
SM
4611 if (flags & MSG_WAITALL)
4612 min_ret = iov_iter_count(&kmsg->msg.msg_iter);
4613
7a7cacba
PB
4614 ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
4615 kmsg->uaddr, flags);
0e1b6fe3
PB
4616 if (force_nonblock && ret == -EAGAIN)
4617 return io_setup_async_msg(req, kmsg);
7a7cacba
PB
4618 if (ret == -ERESTARTSYS)
4619 ret = -EINTR;
03b1230c 4620
7fbb1b54
PB
4621 if (req->flags & REQ_F_BUFFER_SELECTED)
4622 cflags = io_put_recv_kbuf(req);
257e84a5
PB
4623 /* fast path, check for non-NULL to avoid function call */
4624 if (kmsg->free_iov)
4625 kfree(kmsg->free_iov);
99bc4c38 4626 req->flags &= ~REQ_F_NEED_CLEANUP;
0031275d 4627 if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
4e88d6e7 4628 req_set_fail_links(req);
889fca73 4629 __io_req_complete(req, issue_flags, ret, cflags);
03b1230c 4630 return 0;
0fa03c62 4631}
5d17b4a4 4632
889fca73 4633static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
fddaface 4634{
6b754c8b 4635 struct io_buffer *kbuf;
7a7cacba
PB
4636 struct io_sr_msg *sr = &req->sr_msg;
4637 struct msghdr msg;
4638 void __user *buf = sr->buf;
fddaface 4639 struct socket *sock;
7a7cacba
PB
4640 struct iovec iov;
4641 unsigned flags;
0031275d 4642 int min_ret = 0;
bcda7baa 4643 int ret, cflags = 0;
45d189c6 4644 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
fddaface 4645
dba4a925 4646 sock = sock_from_file(req->file);
7a7cacba 4647 if (unlikely(!sock))
dba4a925 4648 return -ENOTSOCK;
fddaface 4649
bc02ef33 4650 if (req->flags & REQ_F_BUFFER_SELECT) {
7fbb1b54 4651 kbuf = io_recv_buffer_select(req, !force_nonblock);
bcda7baa
JA
4652 if (IS_ERR(kbuf))
4653 return PTR_ERR(kbuf);
7a7cacba 4654 buf = u64_to_user_ptr(kbuf->addr);
bc02ef33 4655 }
bcda7baa 4656
7a7cacba 4657 ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
14c32eee
PB
4658 if (unlikely(ret))
4659 goto out_free;
fddaface 4660
7a7cacba
PB
4661 msg.msg_name = NULL;
4662 msg.msg_control = NULL;
4663 msg.msg_controllen = 0;
4664 msg.msg_namelen = 0;
4665 msg.msg_iocb = NULL;
4666 msg.msg_flags = 0;
fddaface 4667
76cd979f 4668 flags = req->sr_msg.msg_flags | MSG_NOSIGNAL;
7a7cacba
PB
4669 if (flags & MSG_DONTWAIT)
4670 req->flags |= REQ_F_NOWAIT;
4671 else if (force_nonblock)
4672 flags |= MSG_DONTWAIT;
4673
0031275d
SM
4674 if (flags & MSG_WAITALL)
4675 min_ret = iov_iter_count(&msg.msg_iter);
4676
7a7cacba
PB
4677 ret = sock_recvmsg(sock, &msg, flags);
4678 if (force_nonblock && ret == -EAGAIN)
4679 return -EAGAIN;
4680 if (ret == -ERESTARTSYS)
4681 ret = -EINTR;
14c32eee 4682out_free:
7fbb1b54
PB
4683 if (req->flags & REQ_F_BUFFER_SELECTED)
4684 cflags = io_put_recv_kbuf(req);
0031275d 4685 if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
fddaface 4686 req_set_fail_links(req);
889fca73 4687 __io_req_complete(req, issue_flags, ret, cflags);
fddaface 4688 return 0;
fddaface
JA
4689}
4690
3529d8c2 4691static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
17f2fe35 4692{
8ed8d3c3
JA
4693 struct io_accept *accept = &req->accept;
4694
14587a46 4695 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
17f2fe35 4696 return -EINVAL;
8042d6ce 4697 if (sqe->ioprio || sqe->len || sqe->buf_index)
17f2fe35
JA
4698 return -EINVAL;
4699
d55e5f5b
JA
4700 accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
4701 accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
8ed8d3c3 4702 accept->flags = READ_ONCE(sqe->accept_flags);
09952e3e 4703 accept->nofile = rlimit(RLIMIT_NOFILE);
8ed8d3c3 4704 return 0;
8ed8d3c3 4705}
17f2fe35 4706
889fca73 4707static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
8ed8d3c3
JA
4708{
4709 struct io_accept *accept = &req->accept;
45d189c6 4710 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
ac45abc0 4711 unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
8ed8d3c3
JA
4712 int ret;
4713
e697deed
JX
4714 if (req->file->f_flags & O_NONBLOCK)
4715 req->flags |= REQ_F_NOWAIT;
4716
8ed8d3c3 4717 ret = __sys_accept4_file(req->file, file_flags, accept->addr,
09952e3e
JA
4718 accept->addr_len, accept->flags,
4719 accept->nofile);
8ed8d3c3 4720 if (ret == -EAGAIN && force_nonblock)
17f2fe35 4721 return -EAGAIN;
ac45abc0
PB
4722 if (ret < 0) {
4723 if (ret == -ERESTARTSYS)
4724 ret = -EINTR;
4e88d6e7 4725 req_set_fail_links(req);
ac45abc0 4726 }
889fca73 4727 __io_req_complete(req, issue_flags, ret, 0);
17f2fe35 4728 return 0;
8ed8d3c3
JA
4729}
4730
93642ef8
PB
4731static int io_connect_prep_async(struct io_kiocb *req)
4732{
4733 struct io_async_connect *io = req->async_data;
4734 struct io_connect *conn = &req->connect;
4735
4736 return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
4737}
4738
3529d8c2 4739static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
f499a021 4740{
3529d8c2 4741 struct io_connect *conn = &req->connect;
f499a021 4742
14587a46 4743 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3fbb51c1
JA
4744 return -EINVAL;
4745 if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags)
4746 return -EINVAL;
4747
3529d8c2
JA
4748 conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
4749 conn->addr_len = READ_ONCE(sqe->addr2);
93642ef8 4750 return 0;
f499a021
JA
4751}
4752
889fca73 4753static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
f8e85cf2 4754{
e8c2bc1f 4755 struct io_async_connect __io, *io;
f8e85cf2 4756 unsigned file_flags;
3fbb51c1 4757 int ret;
45d189c6 4758 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
f8e85cf2 4759
e8c2bc1f
JA
4760 if (req->async_data) {
4761 io = req->async_data;
f499a021 4762 } else {
3529d8c2
JA
4763 ret = move_addr_to_kernel(req->connect.addr,
4764 req->connect.addr_len,
e8c2bc1f 4765 &__io.address);
f499a021
JA
4766 if (ret)
4767 goto out;
4768 io = &__io;
4769 }
4770
3fbb51c1
JA
4771 file_flags = force_nonblock ? O_NONBLOCK : 0;
4772
e8c2bc1f 4773 ret = __sys_connect_file(req->file, &io->address,
3fbb51c1 4774 req->connect.addr_len, file_flags);
87f80d62 4775 if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
e8c2bc1f 4776 if (req->async_data)
b7bb4f7d 4777 return -EAGAIN;
e8c2bc1f 4778 if (io_alloc_async_data(req)) {
f499a021
JA
4779 ret = -ENOMEM;
4780 goto out;
4781 }
e8c2bc1f 4782 memcpy(req->async_data, &__io, sizeof(__io));
f8e85cf2 4783 return -EAGAIN;
f499a021 4784 }
f8e85cf2
JA
4785 if (ret == -ERESTARTSYS)
4786 ret = -EINTR;
f499a021 4787out:
4e88d6e7
JA
4788 if (ret < 0)
4789 req_set_fail_links(req);
889fca73 4790 __io_req_complete(req, issue_flags, ret, 0);
f8e85cf2 4791 return 0;
469956e8
Y
4792}
4793#else /* !CONFIG_NET */
99a10081
JA
4794#define IO_NETOP_FN(op) \
4795static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
4796{ \
4797 return -EOPNOTSUPP; \
4798}
4799
4800#define IO_NETOP_PREP(op) \
4801IO_NETOP_FN(op) \
4802static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
4803{ \
4804 return -EOPNOTSUPP; \
4805} \
4806
4807#define IO_NETOP_PREP_ASYNC(op) \
4808IO_NETOP_PREP(op) \
4809static int io_##op##_prep_async(struct io_kiocb *req) \
4810{ \
4811 return -EOPNOTSUPP; \
4812}
4813
4814IO_NETOP_PREP_ASYNC(sendmsg);
4815IO_NETOP_PREP_ASYNC(recvmsg);
4816IO_NETOP_PREP_ASYNC(connect);
4817IO_NETOP_PREP(accept);
4818IO_NETOP_FN(send);
4819IO_NETOP_FN(recv);
469956e8 4820#endif /* CONFIG_NET */
f8e85cf2 4821
d7718a9d
JA
4822struct io_poll_table {
4823 struct poll_table_struct pt;
4824 struct io_kiocb *req;
4825 int error;
4826};
ce593a6c 4827
d7718a9d
JA
4828static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll,
4829 __poll_t mask, task_work_func_t func)
4830{
aa96bf8a 4831 int ret;
d7718a9d
JA
4832
4833 /* for instances that support it check for an event match first: */
4834 if (mask && !(mask & poll->events))
4835 return 0;
4836
4837 trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
4838
4839 list_del_init(&poll->wait.entry);
4840
d7718a9d 4841 req->result = mask;
7cbf1722 4842 req->task_work.func = func;
6d816e08 4843
d7718a9d 4844 /*
e3aabf95
JA
4845 * If this fails, then the task is exiting. When a task exits, the
4846 * work gets canceled, so just cancel this request as well instead
4847 * of executing it. We can't safely execute it anyway, as we may not
4848 * have the needed state needed for it anyway.
d7718a9d 4849 */
355fb9e2 4850 ret = io_req_task_work_add(req);
aa96bf8a 4851 if (unlikely(ret)) {
e3aabf95 4852 WRITE_ONCE(poll->canceled, true);
eab30c4d 4853 io_req_task_work_add_fallback(req, func);
aa96bf8a 4854 }
d7718a9d
JA
4855 return 1;
4856}
4857
74ce6ce4
JA
4858static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
4859 __acquires(&req->ctx->completion_lock)
4860{
4861 struct io_ring_ctx *ctx = req->ctx;
4862
4863 if (!req->result && !READ_ONCE(poll->canceled)) {
4864 struct poll_table_struct pt = { ._key = poll->events };
4865
4866 req->result = vfs_poll(req->file, &pt) & poll->events;
4867 }
4868
4869 spin_lock_irq(&ctx->completion_lock);
4870 if (!req->result && !READ_ONCE(poll->canceled)) {
4871 add_wait_queue(poll->head, &poll->wait);
4872 return true;
4873 }
4874
4875 return false;
4876}
4877
d4e7cd36 4878static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
18bceab1 4879{
e8c2bc1f 4880 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
d4e7cd36 4881 if (req->opcode == IORING_OP_POLL_ADD)
e8c2bc1f 4882 return req->async_data;
d4e7cd36
JA
4883 return req->apoll->double_poll;
4884}
4885
4886static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
4887{
4888 if (req->opcode == IORING_OP_POLL_ADD)
4889 return &req->poll;
4890 return &req->apoll->poll;
4891}
4892
4893static void io_poll_remove_double(struct io_kiocb *req)
4894{
4895 struct io_poll_iocb *poll = io_poll_get_double(req);
18bceab1
JA
4896
4897 lockdep_assert_held(&req->ctx->completion_lock);
4898
4899 if (poll && poll->head) {
4900 struct wait_queue_head *head = poll->head;
4901
4902 spin_lock(&head->lock);
4903 list_del_init(&poll->wait.entry);
4904 if (poll->wait.private)
de9b4cca 4905 req_ref_put(req);
18bceab1
JA
4906 poll->head = NULL;
4907 spin_unlock(&head->lock);
4908 }
4909}
4910
88e41cf9 4911static bool io_poll_complete(struct io_kiocb *req, __poll_t mask, int error)
18bceab1
JA
4912{
4913 struct io_ring_ctx *ctx = req->ctx;
88e41cf9 4914 unsigned flags = IORING_CQE_F_MORE;
18bceab1 4915
88e41cf9 4916 if (!error && req->poll.canceled) {
45ab03b1 4917 error = -ECANCELED;
88e41cf9
JA
4918 req->poll.events |= EPOLLONESHOT;
4919 }
5082620f
JA
4920 if (!error)
4921 error = mangle_poll(mask);
b69de288
JA
4922 if (req->poll.events & EPOLLONESHOT)
4923 flags = 0;
4924 if (!__io_cqring_fill_event(req, error, flags)) {
5082620f 4925 io_poll_remove_waitqs(req);
88e41cf9
JA
4926 req->poll.done = true;
4927 flags = 0;
4928 }
18bceab1 4929 io_commit_cqring(ctx);
88e41cf9 4930 return !(flags & IORING_CQE_F_MORE);
18bceab1
JA
4931}
4932
dd221f46 4933static void io_poll_task_func(struct callback_head *cb)
18bceab1 4934{
dd221f46 4935 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
18bceab1 4936 struct io_ring_ctx *ctx = req->ctx;
dd221f46 4937 struct io_kiocb *nxt;
18bceab1
JA
4938
4939 if (io_poll_rewait(req, &req->poll)) {
4940 spin_unlock_irq(&ctx->completion_lock);
dd221f46 4941 } else {
88e41cf9
JA
4942 bool done, post_ev;
4943
4944 post_ev = done = io_poll_complete(req, req->result, 0);
4945 if (done) {
4946 hash_del(&req->hash_node);
4947 } else if (!(req->poll.events & EPOLLONESHOT)) {
4948 post_ev = true;
4949 req->result = 0;
4950 add_wait_queue(req->poll.head, &req->poll.wait);
4951 }
dd221f46 4952 spin_unlock_irq(&ctx->completion_lock);
18bceab1 4953
88e41cf9
JA
4954 if (post_ev)
4955 io_cqring_ev_posted(ctx);
4956 if (done) {
4957 nxt = io_put_req_find_next(req);
4958 if (nxt)
4959 __io_req_task_submit(nxt);
4960 }
dd221f46 4961 }
18bceab1
JA
4962}
4963
4964static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode,
4965 int sync, void *key)
4966{
4967 struct io_kiocb *req = wait->private;
d4e7cd36 4968 struct io_poll_iocb *poll = io_poll_get_single(req);
18bceab1
JA
4969 __poll_t mask = key_to_poll(key);
4970
4971 /* for instances that support it check for an event match first: */
4972 if (mask && !(mask & poll->events))
4973 return 0;
88e41cf9
JA
4974 if (!(poll->events & EPOLLONESHOT))
4975 return poll->wait.func(&poll->wait, mode, sync, key);
18bceab1 4976
8706e04e
JA
4977 list_del_init(&wait->entry);
4978
807abcb0 4979 if (poll && poll->head) {
18bceab1
JA
4980 bool done;
4981
807abcb0
JA
4982 spin_lock(&poll->head->lock);
4983 done = list_empty(&poll->wait.entry);
18bceab1 4984 if (!done)
807abcb0 4985 list_del_init(&poll->wait.entry);
d4e7cd36
JA
4986 /* make sure double remove sees this as being gone */
4987 wait->private = NULL;
807abcb0 4988 spin_unlock(&poll->head->lock);
c8b5e260
JA
4989 if (!done) {
4990 /* use wait func handler, so it matches the rq type */
4991 poll->wait.func(&poll->wait, mode, sync, key);
4992 }
18bceab1 4993 }
de9b4cca 4994 req_ref_put(req);
18bceab1
JA
4995 return 1;
4996}
4997
4998static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
4999 wait_queue_func_t wake_func)
5000{
5001 poll->head = NULL;
5002 poll->done = false;
5003 poll->canceled = false;
b69de288 5004 poll->update_events = poll->update_user_data = false;
464dca61
JA
5005#define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
5006 /* mask in events that we always want/need */
5007 poll->events = events | IO_POLL_UNMASK;
18bceab1
JA
5008 INIT_LIST_HEAD(&poll->wait.entry);
5009 init_waitqueue_func_entry(&poll->wait, wake_func);
5010}
5011
5012static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
807abcb0
JA
5013 struct wait_queue_head *head,
5014 struct io_poll_iocb **poll_ptr)
18bceab1
JA
5015{
5016 struct io_kiocb *req = pt->req;
5017
5018 /*
5019 * If poll->head is already set, it's because the file being polled
5020 * uses multiple waitqueues for poll handling (eg one for read, one
5021 * for write). Setup a separate io_poll_iocb if this happens.
5022 */
5023 if (unlikely(poll->head)) {
58852d4d
PB
5024 struct io_poll_iocb *poll_one = poll;
5025
18bceab1 5026 /* already have a 2nd entry, fail a third attempt */
807abcb0 5027 if (*poll_ptr) {
18bceab1
JA
5028 pt->error = -EINVAL;
5029 return;
5030 }
1c3b3e65
JA
5031 /* double add on the same waitqueue head, ignore */
5032 if (poll->head == head)
5033 return;
18bceab1
JA
5034 poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
5035 if (!poll) {
5036 pt->error = -ENOMEM;
5037 return;
5038 }
58852d4d 5039 io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
de9b4cca 5040 req_ref_get(req);
18bceab1 5041 poll->wait.private = req;
807abcb0 5042 *poll_ptr = poll;
18bceab1
JA
5043 }
5044
5045 pt->error = 0;
5046 poll->head = head;
a31eb4a2
JX
5047
5048 if (poll->events & EPOLLEXCLUSIVE)
5049 add_wait_queue_exclusive(head, &poll->wait);
5050 else
5051 add_wait_queue(head, &poll->wait);
18bceab1
JA
5052}
5053
5054static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
5055 struct poll_table_struct *p)
5056{
5057 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
807abcb0 5058 struct async_poll *apoll = pt->req->apoll;
18bceab1 5059
807abcb0 5060 __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
18bceab1
JA
5061}
5062
d7718a9d
JA
5063static void io_async_task_func(struct callback_head *cb)
5064{
5065 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
5066 struct async_poll *apoll = req->apoll;
5067 struct io_ring_ctx *ctx = req->ctx;
5068
5069 trace_io_uring_task_run(req->ctx, req->opcode, req->user_data);
5070
74ce6ce4 5071 if (io_poll_rewait(req, &apoll->poll)) {
d7718a9d 5072 spin_unlock_irq(&ctx->completion_lock);
74ce6ce4 5073 return;
d7718a9d
JA
5074 }
5075
31067255 5076 /* If req is still hashed, it cannot have been canceled. Don't check. */
0be0b0e3 5077 if (hash_hashed(&req->hash_node))
74ce6ce4 5078 hash_del(&req->hash_node);
2bae047e 5079
d4e7cd36 5080 io_poll_remove_double(req);
74ce6ce4
JA
5081 spin_unlock_irq(&ctx->completion_lock);
5082
0be0b0e3
PB
5083 if (!READ_ONCE(apoll->poll.canceled))
5084 __io_req_task_submit(req);
5085 else
2593553a 5086 io_req_complete_failed(req, -ECANCELED);
aa340845 5087
807abcb0 5088 kfree(apoll->double_poll);
31067255 5089 kfree(apoll);
d7718a9d
JA
5090}
5091
5092static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5093 void *key)
5094{
5095 struct io_kiocb *req = wait->private;
5096 struct io_poll_iocb *poll = &req->apoll->poll;
5097
5098 trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data,
5099 key_to_poll(key));
5100
5101 return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func);
5102}
5103
5104static void io_poll_req_insert(struct io_kiocb *req)
5105{
5106 struct io_ring_ctx *ctx = req->ctx;
5107 struct hlist_head *list;
5108
5109 list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
5110 hlist_add_head(&req->hash_node, list);
5111}
5112
5113static __poll_t __io_arm_poll_handler(struct io_kiocb *req,
5114 struct io_poll_iocb *poll,
5115 struct io_poll_table *ipt, __poll_t mask,
5116 wait_queue_func_t wake_func)
5117 __acquires(&ctx->completion_lock)
5118{
5119 struct io_ring_ctx *ctx = req->ctx;
5120 bool cancel = false;
5121
4d52f338 5122 INIT_HLIST_NODE(&req->hash_node);
18bceab1 5123 io_init_poll_iocb(poll, mask, wake_func);
b90cd197 5124 poll->file = req->file;
18bceab1 5125 poll->wait.private = req;
d7718a9d
JA
5126
5127 ipt->pt._key = mask;
5128 ipt->req = req;
5129 ipt->error = -EINVAL;
5130
d7718a9d
JA
5131 mask = vfs_poll(req->file, &ipt->pt) & poll->events;
5132
5133 spin_lock_irq(&ctx->completion_lock);
5134 if (likely(poll->head)) {
5135 spin_lock(&poll->head->lock);
5136 if (unlikely(list_empty(&poll->wait.entry))) {
5137 if (ipt->error)
5138 cancel = true;
5139 ipt->error = 0;
5140 mask = 0;
5141 }
88e41cf9 5142 if ((mask && (poll->events & EPOLLONESHOT)) || ipt->error)
d7718a9d
JA
5143 list_del_init(&poll->wait.entry);
5144 else if (cancel)
5145 WRITE_ONCE(poll->canceled, true);
5146 else if (!poll->done) /* actually waiting for an event */
5147 io_poll_req_insert(req);
5148 spin_unlock(&poll->head->lock);
5149 }
5150
5151 return mask;
5152}
5153
5154static bool io_arm_poll_handler(struct io_kiocb *req)
5155{
5156 const struct io_op_def *def = &io_op_defs[req->opcode];
5157 struct io_ring_ctx *ctx = req->ctx;
5158 struct async_poll *apoll;
5159 struct io_poll_table ipt;
5160 __poll_t mask, ret;
9dab14b8 5161 int rw;
d7718a9d
JA
5162
5163 if (!req->file || !file_can_poll(req->file))
5164 return false;
24c74678 5165 if (req->flags & REQ_F_POLLED)
d7718a9d 5166 return false;
9dab14b8
JA
5167 if (def->pollin)
5168 rw = READ;
5169 else if (def->pollout)
5170 rw = WRITE;
5171 else
5172 return false;
5173 /* if we can't nonblock try, then no point in arming a poll handler */
7b29f92d 5174 if (!io_file_supports_async(req, rw))
d7718a9d
JA
5175 return false;
5176
5177 apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
5178 if (unlikely(!apoll))
5179 return false;
807abcb0 5180 apoll->double_poll = NULL;
d7718a9d
JA
5181
5182 req->flags |= REQ_F_POLLED;
d7718a9d 5183 req->apoll = apoll;
d7718a9d 5184
88e41cf9 5185 mask = EPOLLONESHOT;
d7718a9d 5186 if (def->pollin)
8755d97a 5187 mask |= POLLIN | POLLRDNORM;
d7718a9d
JA
5188 if (def->pollout)
5189 mask |= POLLOUT | POLLWRNORM;
901341bb
LH
5190
5191 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5192 if ((req->opcode == IORING_OP_RECVMSG) &&
5193 (req->sr_msg.msg_flags & MSG_ERRQUEUE))
5194 mask &= ~POLLIN;
5195
d7718a9d
JA
5196 mask |= POLLERR | POLLPRI;
5197
5198 ipt.pt._qproc = io_async_queue_proc;
5199
5200 ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask,
5201 io_async_wake);
a36da65c 5202 if (ret || ipt.error) {
d4e7cd36 5203 io_poll_remove_double(req);
d7718a9d 5204 spin_unlock_irq(&ctx->completion_lock);
807abcb0 5205 kfree(apoll->double_poll);
d7718a9d
JA
5206 kfree(apoll);
5207 return false;
5208 }
5209 spin_unlock_irq(&ctx->completion_lock);
5210 trace_io_uring_poll_arm(ctx, req->opcode, req->user_data, mask,
5211 apoll->poll.events);
5212 return true;
5213}
5214
5215static bool __io_poll_remove_one(struct io_kiocb *req,
b2e720ac 5216 struct io_poll_iocb *poll, bool do_cancel)
221c5eb2 5217{
b41e9852 5218 bool do_complete = false;
221c5eb2 5219
5082620f
JA
5220 if (!poll->head)
5221 return false;
221c5eb2 5222 spin_lock(&poll->head->lock);
b2e720ac
JA
5223 if (do_cancel)
5224 WRITE_ONCE(poll->canceled, true);
392edb45
JA
5225 if (!list_empty(&poll->wait.entry)) {
5226 list_del_init(&poll->wait.entry);
b41e9852 5227 do_complete = true;
221c5eb2
JA
5228 }
5229 spin_unlock(&poll->head->lock);
3bfa5bcb 5230 hash_del(&req->hash_node);
d7718a9d
JA
5231 return do_complete;
5232}
5233
b2c3f7e1 5234static bool io_poll_remove_waitqs(struct io_kiocb *req)
d7718a9d
JA
5235{
5236 bool do_complete;
5237
d4e7cd36
JA
5238 io_poll_remove_double(req);
5239
d7718a9d 5240 if (req->opcode == IORING_OP_POLL_ADD) {
b2e720ac 5241 do_complete = __io_poll_remove_one(req, &req->poll, true);
d7718a9d 5242 } else {
3bfa5bcb
JA
5243 struct async_poll *apoll = req->apoll;
5244
d7718a9d 5245 /* non-poll requests have submit ref still */
b2e720ac 5246 do_complete = __io_poll_remove_one(req, &apoll->poll, true);
3bfa5bcb 5247 if (do_complete) {
d7718a9d 5248 io_put_req(req);
807abcb0 5249 kfree(apoll->double_poll);
3bfa5bcb
JA
5250 kfree(apoll);
5251 }
b1f573bd
XW
5252 }
5253
b2c3f7e1
JA
5254 return do_complete;
5255}
5256
5257static bool io_poll_remove_one(struct io_kiocb *req)
5258{
5259 bool do_complete;
5260
5261 do_complete = io_poll_remove_waitqs(req);
b41e9852
JA
5262 if (do_complete) {
5263 io_cqring_fill_event(req, -ECANCELED);
5264 io_commit_cqring(req->ctx);
f254ac04 5265 req_set_fail_links(req);
216578e5 5266 io_put_req_deferred(req, 1);
b41e9852
JA
5267 }
5268
5269 return do_complete;
221c5eb2
JA
5270}
5271
76e1b642
JA
5272/*
5273 * Returns true if we found and killed one or more poll requests
5274 */
6b81928d
PB
5275static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
5276 struct files_struct *files)
221c5eb2 5277{
78076bb6 5278 struct hlist_node *tmp;
221c5eb2 5279 struct io_kiocb *req;
8e2e1faf 5280 int posted = 0, i;
221c5eb2
JA
5281
5282 spin_lock_irq(&ctx->completion_lock);
78076bb6
JA
5283 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
5284 struct hlist_head *list;
5285
5286 list = &ctx->cancel_hash[i];
f3606e3a 5287 hlist_for_each_entry_safe(req, tmp, list, hash_node) {
6b81928d 5288 if (io_match_task(req, tsk, files))
f3606e3a
JA
5289 posted += io_poll_remove_one(req);
5290 }
221c5eb2
JA
5291 }
5292 spin_unlock_irq(&ctx->completion_lock);
b41e9852 5293
8e2e1faf
JA
5294 if (posted)
5295 io_cqring_ev_posted(ctx);
76e1b642
JA
5296
5297 return posted != 0;
221c5eb2
JA
5298}
5299
b2cb805f 5300static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, __u64 sqe_addr)
47f46768 5301{
78076bb6 5302 struct hlist_head *list;
47f46768
JA
5303 struct io_kiocb *req;
5304
78076bb6
JA
5305 list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
5306 hlist_for_each_entry(req, list, hash_node) {
b41e9852
JA
5307 if (sqe_addr != req->user_data)
5308 continue;
b2cb805f 5309 return req;
47f46768
JA
5310 }
5311
b2cb805f
JA
5312 return NULL;
5313}
5314
5315static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr)
5316{
5317 struct io_kiocb *req;
5318
5319 req = io_poll_find(ctx, sqe_addr);
5320 if (!req)
5321 return -ENOENT;
5322 if (io_poll_remove_one(req))
5323 return 0;
5324
5325 return -EALREADY;
47f46768
JA
5326}
5327
3529d8c2
JA
5328static int io_poll_remove_prep(struct io_kiocb *req,
5329 const struct io_uring_sqe *sqe)
0969e783 5330{
0969e783
JA
5331 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5332 return -EINVAL;
5333 if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
5334 sqe->poll_events)
5335 return -EINVAL;
5336
018043be 5337 req->poll_remove.addr = READ_ONCE(sqe->addr);
0969e783
JA
5338 return 0;
5339}
5340
221c5eb2
JA
5341/*
5342 * Find a running poll command that matches one specified in sqe->addr,
5343 * and remove it if found.
5344 */
61e98203 5345static int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
221c5eb2
JA
5346{
5347 struct io_ring_ctx *ctx = req->ctx;
47f46768 5348 int ret;
221c5eb2 5349
221c5eb2 5350 spin_lock_irq(&ctx->completion_lock);
018043be 5351 ret = io_poll_cancel(ctx, req->poll_remove.addr);
221c5eb2
JA
5352 spin_unlock_irq(&ctx->completion_lock);
5353
4e88d6e7
JA
5354 if (ret < 0)
5355 req_set_fail_links(req);
e1e16097 5356 io_req_complete(req, ret);
221c5eb2
JA
5357 return 0;
5358}
5359
221c5eb2
JA
5360static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5361 void *key)
5362{
c2f2eb7d
JA
5363 struct io_kiocb *req = wait->private;
5364 struct io_poll_iocb *poll = &req->poll;
221c5eb2 5365
d7718a9d 5366 return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func);
221c5eb2
JA
5367}
5368
221c5eb2
JA
5369static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
5370 struct poll_table_struct *p)
5371{
5372 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
5373
e8c2bc1f 5374 __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
eac406c6
JA
5375}
5376
3529d8c2 5377static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
221c5eb2
JA
5378{
5379 struct io_poll_iocb *poll = &req->poll;
88e41cf9 5380 u32 events, flags;
221c5eb2
JA
5381
5382 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5383 return -EINVAL;
b69de288 5384 if (sqe->ioprio || sqe->buf_index)
88e41cf9
JA
5385 return -EINVAL;
5386 flags = READ_ONCE(sqe->len);
b69de288
JA
5387 if (flags & ~(IORING_POLL_ADD_MULTI | IORING_POLL_UPDATE_EVENTS |
5388 IORING_POLL_UPDATE_USER_DATA))
221c5eb2 5389 return -EINVAL;
5769a351
JX
5390 events = READ_ONCE(sqe->poll32_events);
5391#ifdef __BIG_ENDIAN
5392 events = swahw32(events);
5393#endif
b69de288 5394 if (!(flags & IORING_POLL_ADD_MULTI))
88e41cf9 5395 events |= EPOLLONESHOT;
b69de288
JA
5396 poll->update_events = poll->update_user_data = false;
5397 if (flags & IORING_POLL_UPDATE_EVENTS) {
5398 poll->update_events = true;
5399 poll->old_user_data = READ_ONCE(sqe->addr);
5400 }
5401 if (flags & IORING_POLL_UPDATE_USER_DATA) {
5402 poll->update_user_data = true;
5403 poll->new_user_data = READ_ONCE(sqe->off);
5404 }
5405 if (!(poll->update_events || poll->update_user_data) &&
5406 (sqe->off || sqe->addr))
5407 return -EINVAL;
88e41cf9
JA
5408 poll->events = demangle_poll(events) |
5409 (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
0969e783
JA
5410 return 0;
5411}
5412
b69de288 5413static int __io_poll_add(struct io_kiocb *req)
0969e783
JA
5414{
5415 struct io_poll_iocb *poll = &req->poll;
5416 struct io_ring_ctx *ctx = req->ctx;
5417 struct io_poll_table ipt;
0969e783 5418 __poll_t mask;
0969e783 5419
d7718a9d 5420 ipt.pt._qproc = io_poll_queue_proc;
36703247 5421
d7718a9d
JA
5422 mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,
5423 io_poll_wake);
221c5eb2 5424
8c838788 5425 if (mask) { /* no async, we'd stolen it */
221c5eb2 5426 ipt.error = 0;
b0dd8a41 5427 io_poll_complete(req, mask, 0);
221c5eb2 5428 }
221c5eb2
JA
5429 spin_unlock_irq(&ctx->completion_lock);
5430
8c838788
JA
5431 if (mask) {
5432 io_cqring_ev_posted(ctx);
88e41cf9
JA
5433 if (poll->events & EPOLLONESHOT)
5434 io_put_req(req);
221c5eb2 5435 }
8c838788 5436 return ipt.error;
221c5eb2
JA
5437}
5438
b69de288
JA
5439static int io_poll_update(struct io_kiocb *req)
5440{
5441 struct io_ring_ctx *ctx = req->ctx;
5442 struct io_kiocb *preq;
5443 int ret;
5444
5445 spin_lock_irq(&ctx->completion_lock);
5446 preq = io_poll_find(ctx, req->poll.old_user_data);
5447 if (!preq) {
5448 ret = -ENOENT;
5449 goto err;
5450 } else if (preq->opcode != IORING_OP_POLL_ADD) {
5451 /* don't allow internal poll updates */
5452 ret = -EACCES;
5453 goto err;
5454 }
b2e720ac
JA
5455 if (!__io_poll_remove_one(preq, &preq->poll, false)) {
5456 if (preq->poll.events & EPOLLONESHOT) {
5457 ret = -EALREADY;
5458 goto err;
5459 }
b69de288
JA
5460 }
5461 /* we now have a detached poll request. reissue. */
5462 ret = 0;
5463err:
5464 spin_unlock_irq(&ctx->completion_lock);
5465 if (ret < 0) {
5466 req_set_fail_links(req);
5467 io_req_complete(req, ret);
5468 return 0;
5469 }
5470 /* only mask one event flags, keep behavior flags */
5471 if (req->poll.update_events) {
5472 preq->poll.events &= ~0xffff;
5473 preq->poll.events |= req->poll.events & 0xffff;
5474 preq->poll.events |= IO_POLL_UNMASK;
5475 }
5476 if (req->poll.update_user_data)
5477 preq->user_data = req->poll.new_user_data;
5478
5479 /* complete update request, we're done with it */
5480 io_req_complete(req, ret);
5481
5482 ret = __io_poll_add(preq);
5483 if (ret < 0) {
5484 req_set_fail_links(preq);
5485 io_req_complete(preq, ret);
5486 }
5487 return 0;
5488}
5489
5490static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
5491{
5492 if (!req->poll.update_events && !req->poll.update_user_data)
5493 return __io_poll_add(req);
5494 return io_poll_update(req);
5495}
5496
5262f567
JA
5497static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
5498{
ad8a48ac
JA
5499 struct io_timeout_data *data = container_of(timer,
5500 struct io_timeout_data, timer);
5501 struct io_kiocb *req = data->req;
5502 struct io_ring_ctx *ctx = req->ctx;
5262f567
JA
5503 unsigned long flags;
5504
5262f567 5505 spin_lock_irqsave(&ctx->completion_lock, flags);
a71976f3 5506 list_del_init(&req->timeout.list);
01cec8c1
PB
5507 atomic_set(&req->ctx->cq_timeouts,
5508 atomic_read(&req->ctx->cq_timeouts) + 1);
5509
78e19bbe 5510 io_cqring_fill_event(req, -ETIME);
5262f567
JA
5511 io_commit_cqring(ctx);
5512 spin_unlock_irqrestore(&ctx->completion_lock, flags);
5513
5514 io_cqring_ev_posted(ctx);
4e88d6e7 5515 req_set_fail_links(req);
5262f567
JA
5516 io_put_req(req);
5517 return HRTIMER_NORESTART;
5518}
5519
fbd15848
PB
5520static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
5521 __u64 user_data)
f254ac04 5522{
fbd15848 5523 struct io_timeout_data *io;
47f46768
JA
5524 struct io_kiocb *req;
5525 int ret = -ENOENT;
f254ac04 5526
135fcde8 5527 list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
47f46768 5528 if (user_data == req->user_data) {
47f46768
JA
5529 ret = 0;
5530 break;
5531 }
5532 }
5533
5534 if (ret == -ENOENT)
fbd15848
PB
5535 return ERR_PTR(ret);
5536
5537 io = req->async_data;
e8c2bc1f 5538 ret = hrtimer_try_to_cancel(&io->timer);
f254ac04 5539 if (ret == -1)
fbd15848 5540 return ERR_PTR(-EALREADY);
a71976f3 5541 list_del_init(&req->timeout.list);
fbd15848
PB
5542 return req;
5543}
47f46768 5544
fbd15848
PB
5545static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
5546{
5547 struct io_kiocb *req = io_timeout_extract(ctx, user_data);
5548
5549 if (IS_ERR(req))
5550 return PTR_ERR(req);
f254ac04
JA
5551
5552 req_set_fail_links(req);
f254ac04 5553 io_cqring_fill_event(req, -ECANCELED);
216578e5 5554 io_put_req_deferred(req, 1);
f254ac04
JA
5555 return 0;
5556}
5557
9c8e11b3
PB
5558static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
5559 struct timespec64 *ts, enum hrtimer_mode mode)
47f46768 5560{
9c8e11b3
PB
5561 struct io_kiocb *req = io_timeout_extract(ctx, user_data);
5562 struct io_timeout_data *data;
47f46768 5563
9c8e11b3
PB
5564 if (IS_ERR(req))
5565 return PTR_ERR(req);
47f46768 5566
9c8e11b3
PB
5567 req->timeout.off = 0; /* noseq */
5568 data = req->async_data;
5569 list_add_tail(&req->timeout.list, &ctx->timeout_list);
5570 hrtimer_init(&data->timer, CLOCK_MONOTONIC, mode);
5571 data->timer.function = io_timeout_fn;
5572 hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
5573 return 0;
47f46768
JA
5574}
5575
3529d8c2
JA
5576static int io_timeout_remove_prep(struct io_kiocb *req,
5577 const struct io_uring_sqe *sqe)
b29472ee 5578{
9c8e11b3
PB
5579 struct io_timeout_rem *tr = &req->timeout_rem;
5580
b29472ee
JA
5581 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5582 return -EINVAL;
61710e43
DA
5583 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5584 return -EINVAL;
9c8e11b3 5585 if (sqe->ioprio || sqe->buf_index || sqe->len)
b29472ee
JA
5586 return -EINVAL;
5587
9c8e11b3
PB
5588 tr->addr = READ_ONCE(sqe->addr);
5589 tr->flags = READ_ONCE(sqe->timeout_flags);
5590 if (tr->flags & IORING_TIMEOUT_UPDATE) {
5591 if (tr->flags & ~(IORING_TIMEOUT_UPDATE|IORING_TIMEOUT_ABS))
5592 return -EINVAL;
5593 if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
5594 return -EFAULT;
5595 } else if (tr->flags) {
5596 /* timeout removal doesn't support flags */
b29472ee 5597 return -EINVAL;
9c8e11b3 5598 }
b29472ee 5599
b29472ee
JA
5600 return 0;
5601}
5602
8662daec
PB
5603static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
5604{
5605 return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
5606 : HRTIMER_MODE_REL;
5607}
5608
11365043
JA
5609/*
5610 * Remove or update an existing timeout command
5611 */
61e98203 5612static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
11365043 5613{
9c8e11b3 5614 struct io_timeout_rem *tr = &req->timeout_rem;
11365043 5615 struct io_ring_ctx *ctx = req->ctx;
47f46768 5616 int ret;
11365043 5617
11365043 5618 spin_lock_irq(&ctx->completion_lock);
8662daec 5619 if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE))
9c8e11b3 5620 ret = io_timeout_cancel(ctx, tr->addr);
8662daec
PB
5621 else
5622 ret = io_timeout_update(ctx, tr->addr, &tr->ts,
5623 io_translate_timeout_mode(tr->flags));
11365043 5624
47f46768 5625 io_cqring_fill_event(req, ret);
11365043
JA
5626 io_commit_cqring(ctx);
5627 spin_unlock_irq(&ctx->completion_lock);
5262f567 5628 io_cqring_ev_posted(ctx);
4e88d6e7
JA
5629 if (ret < 0)
5630 req_set_fail_links(req);
ec9c02ad 5631 io_put_req(req);
11365043 5632 return 0;
5262f567
JA
5633}
5634
3529d8c2 5635static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
2d28390a 5636 bool is_timeout_link)
5262f567 5637{
ad8a48ac 5638 struct io_timeout_data *data;
a41525ab 5639 unsigned flags;
56080b02 5640 u32 off = READ_ONCE(sqe->off);
5262f567 5641
ad8a48ac 5642 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5262f567 5643 return -EINVAL;
ad8a48ac 5644 if (sqe->ioprio || sqe->buf_index || sqe->len != 1)
a41525ab 5645 return -EINVAL;
56080b02 5646 if (off && is_timeout_link)
2d28390a 5647 return -EINVAL;
a41525ab
JA
5648 flags = READ_ONCE(sqe->timeout_flags);
5649 if (flags & ~IORING_TIMEOUT_ABS)
5262f567 5650 return -EINVAL;
bdf20073 5651
bfe68a22 5652 req->timeout.off = off;
26a61679 5653
e8c2bc1f 5654 if (!req->async_data && io_alloc_async_data(req))
26a61679
JA
5655 return -ENOMEM;
5656
e8c2bc1f 5657 data = req->async_data;
ad8a48ac 5658 data->req = req;
ad8a48ac
JA
5659
5660 if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
5262f567
JA
5661 return -EFAULT;
5662
8662daec 5663 data->mode = io_translate_timeout_mode(flags);
ad8a48ac 5664 hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode);
2482b58f
PB
5665 if (is_timeout_link)
5666 io_req_track_inflight(req);
ad8a48ac
JA
5667 return 0;
5668}
5669
61e98203 5670static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
ad8a48ac 5671{
ad8a48ac 5672 struct io_ring_ctx *ctx = req->ctx;
e8c2bc1f 5673 struct io_timeout_data *data = req->async_data;
ad8a48ac 5674 struct list_head *entry;
bfe68a22 5675 u32 tail, off = req->timeout.off;
ad8a48ac 5676
733f5c95 5677 spin_lock_irq(&ctx->completion_lock);
93bd25bb 5678
5262f567
JA
5679 /*
5680 * sqe->off holds how many events that need to occur for this
93bd25bb
JA
5681 * timeout event to be satisfied. If it isn't set, then this is
5682 * a pure timeout request, sequence isn't used.
5262f567 5683 */
8eb7e2d0 5684 if (io_is_timeout_noseq(req)) {
93bd25bb
JA
5685 entry = ctx->timeout_list.prev;
5686 goto add;
5687 }
5262f567 5688
bfe68a22
PB
5689 tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
5690 req->timeout.target_seq = tail + off;
5262f567 5691
f010505b
MDG
5692 /* Update the last seq here in case io_flush_timeouts() hasn't.
5693 * This is safe because ->completion_lock is held, and submissions
5694 * and completions are never mixed in the same ->completion_lock section.
5695 */
5696 ctx->cq_last_tm_flush = tail;
5697
5262f567
JA
5698 /*
5699 * Insertion sort, ensuring the first entry in the list is always
5700 * the one we need first.
5701 */
5262f567 5702 list_for_each_prev(entry, &ctx->timeout_list) {
135fcde8
PB
5703 struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
5704 timeout.list);
5262f567 5705
8eb7e2d0 5706 if (io_is_timeout_noseq(nxt))
93bd25bb 5707 continue;
bfe68a22
PB
5708 /* nxt.seq is behind @tail, otherwise would've been completed */
5709 if (off >= nxt->timeout.target_seq - tail)
5262f567
JA
5710 break;
5711 }
93bd25bb 5712add:
135fcde8 5713 list_add(&req->timeout.list, entry);
ad8a48ac
JA
5714 data->timer.function = io_timeout_fn;
5715 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
5262f567 5716 spin_unlock_irq(&ctx->completion_lock);
5262f567
JA
5717 return 0;
5718}
5262f567 5719
f458dd84
PB
5720struct io_cancel_data {
5721 struct io_ring_ctx *ctx;
5722 u64 user_data;
5723};
5724
62755e35
JA
5725static bool io_cancel_cb(struct io_wq_work *work, void *data)
5726{
5727 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
f458dd84 5728 struct io_cancel_data *cd = data;
62755e35 5729
f458dd84 5730 return req->ctx == cd->ctx && req->user_data == cd->user_data;
62755e35
JA
5731}
5732
f458dd84
PB
5733static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
5734 struct io_ring_ctx *ctx)
62755e35 5735{
f458dd84 5736 struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, };
62755e35 5737 enum io_wq_cancel cancel_ret;
62755e35
JA
5738 int ret = 0;
5739
f458dd84 5740 if (!tctx || !tctx->io_wq)
5aa75ed5
JA
5741 return -ENOENT;
5742
f458dd84 5743 cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false);
62755e35
JA
5744 switch (cancel_ret) {
5745 case IO_WQ_CANCEL_OK:
5746 ret = 0;
5747 break;
5748 case IO_WQ_CANCEL_RUNNING:
5749 ret = -EALREADY;
5750 break;
5751 case IO_WQ_CANCEL_NOTFOUND:
5752 ret = -ENOENT;
5753 break;
5754 }
5755
e977d6d3
JA
5756 return ret;
5757}
5758
47f46768
JA
5759static void io_async_find_and_cancel(struct io_ring_ctx *ctx,
5760 struct io_kiocb *req, __u64 sqe_addr,
014db007 5761 int success_ret)
47f46768
JA
5762{
5763 unsigned long flags;
5764 int ret;
5765
f458dd84 5766 ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
47f46768
JA
5767 if (ret != -ENOENT) {
5768 spin_lock_irqsave(&ctx->completion_lock, flags);
5769 goto done;
5770 }
5771
5772 spin_lock_irqsave(&ctx->completion_lock, flags);
5773 ret = io_timeout_cancel(ctx, sqe_addr);
5774 if (ret != -ENOENT)
5775 goto done;
5776 ret = io_poll_cancel(ctx, sqe_addr);
5777done:
b0dd8a41
JA
5778 if (!ret)
5779 ret = success_ret;
47f46768
JA
5780 io_cqring_fill_event(req, ret);
5781 io_commit_cqring(ctx);
5782 spin_unlock_irqrestore(&ctx->completion_lock, flags);
5783 io_cqring_ev_posted(ctx);
5784
4e88d6e7
JA
5785 if (ret < 0)
5786 req_set_fail_links(req);
014db007 5787 io_put_req(req);
47f46768
JA
5788}
5789
3529d8c2
JA
5790static int io_async_cancel_prep(struct io_kiocb *req,
5791 const struct io_uring_sqe *sqe)
e977d6d3 5792{
fbf23849 5793 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
e977d6d3 5794 return -EINVAL;
61710e43
DA
5795 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5796 return -EINVAL;
5797 if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags)
e977d6d3
JA
5798 return -EINVAL;
5799
fbf23849
JA
5800 req->cancel.addr = READ_ONCE(sqe->addr);
5801 return 0;
5802}
5803
61e98203 5804static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
fbf23849
JA
5805{
5806 struct io_ring_ctx *ctx = req->ctx;
58f99373
PB
5807 u64 sqe_addr = req->cancel.addr;
5808 struct io_tctx_node *node;
5809 int ret;
5810
5811 /* tasks should wait for their io-wq threads, so safe w/o sync */
5812 ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
5813 spin_lock_irq(&ctx->completion_lock);
5814 if (ret != -ENOENT)
5815 goto done;
5816 ret = io_timeout_cancel(ctx, sqe_addr);
5817 if (ret != -ENOENT)
5818 goto done;
5819 ret = io_poll_cancel(ctx, sqe_addr);
5820 if (ret != -ENOENT)
5821 goto done;
5822 spin_unlock_irq(&ctx->completion_lock);
5823
5824 /* slow path, try all io-wq's */
5825 io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
5826 ret = -ENOENT;
5827 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
5828 struct io_uring_task *tctx = node->task->io_uring;
fbf23849 5829
58f99373
PB
5830 if (!tctx || !tctx->io_wq)
5831 continue;
5832 ret = io_async_cancel_one(tctx, req->cancel.addr, ctx);
5833 if (ret != -ENOENT)
5834 break;
5835 }
5836 io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
5837
5838 spin_lock_irq(&ctx->completion_lock);
5839done:
5840 io_cqring_fill_event(req, ret);
5841 io_commit_cqring(ctx);
5842 spin_unlock_irq(&ctx->completion_lock);
5843 io_cqring_ev_posted(ctx);
5844
5845 if (ret < 0)
5846 req_set_fail_links(req);
5847 io_put_req(req);
5262f567
JA
5848 return 0;
5849}
5850
269bbe5f 5851static int io_rsrc_update_prep(struct io_kiocb *req,
05f3fb3c
JA
5852 const struct io_uring_sqe *sqe)
5853{
6ca56f84
JA
5854 if (unlikely(req->ctx->flags & IORING_SETUP_SQPOLL))
5855 return -EINVAL;
61710e43
DA
5856 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5857 return -EINVAL;
5858 if (sqe->ioprio || sqe->rw_flags)
05f3fb3c
JA
5859 return -EINVAL;
5860
269bbe5f
BM
5861 req->rsrc_update.offset = READ_ONCE(sqe->off);
5862 req->rsrc_update.nr_args = READ_ONCE(sqe->len);
5863 if (!req->rsrc_update.nr_args)
05f3fb3c 5864 return -EINVAL;
269bbe5f 5865 req->rsrc_update.arg = READ_ONCE(sqe->addr);
05f3fb3c
JA
5866 return 0;
5867}
5868
889fca73 5869static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
fbf23849
JA
5870{
5871 struct io_ring_ctx *ctx = req->ctx;
269bbe5f 5872 struct io_uring_rsrc_update up;
05f3fb3c 5873 int ret;
fbf23849 5874
45d189c6 5875 if (issue_flags & IO_URING_F_NONBLOCK)
05f3fb3c 5876 return -EAGAIN;
05f3fb3c 5877
269bbe5f
BM
5878 up.offset = req->rsrc_update.offset;
5879 up.data = req->rsrc_update.arg;
05f3fb3c
JA
5880
5881 mutex_lock(&ctx->uring_lock);
269bbe5f 5882 ret = __io_sqe_files_update(ctx, &up, req->rsrc_update.nr_args);
05f3fb3c
JA
5883 mutex_unlock(&ctx->uring_lock);
5884
5885 if (ret < 0)
5886 req_set_fail_links(req);
889fca73 5887 __io_req_complete(req, issue_flags, ret, 0);
5262f567
JA
5888 return 0;
5889}
5890
bfe76559 5891static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
f67676d1 5892{
d625c6ee 5893 switch (req->opcode) {
e781573e 5894 case IORING_OP_NOP:
bfe76559 5895 return 0;
f67676d1
JA
5896 case IORING_OP_READV:
5897 case IORING_OP_READ_FIXED:
3a6820f2 5898 case IORING_OP_READ:
bfe76559 5899 return io_read_prep(req, sqe);
f67676d1
JA
5900 case IORING_OP_WRITEV:
5901 case IORING_OP_WRITE_FIXED:
3a6820f2 5902 case IORING_OP_WRITE:
bfe76559 5903 return io_write_prep(req, sqe);
0969e783 5904 case IORING_OP_POLL_ADD:
bfe76559 5905 return io_poll_add_prep(req, sqe);
0969e783 5906 case IORING_OP_POLL_REMOVE:
bfe76559 5907 return io_poll_remove_prep(req, sqe);
8ed8d3c3 5908 case IORING_OP_FSYNC:
1155c76a 5909 return io_fsync_prep(req, sqe);
8ed8d3c3 5910 case IORING_OP_SYNC_FILE_RANGE:
1155c76a 5911 return io_sfr_prep(req, sqe);
03b1230c 5912 case IORING_OP_SENDMSG:
fddaface 5913 case IORING_OP_SEND:
bfe76559 5914 return io_sendmsg_prep(req, sqe);
03b1230c 5915 case IORING_OP_RECVMSG:
fddaface 5916 case IORING_OP_RECV:
bfe76559 5917 return io_recvmsg_prep(req, sqe);
f499a021 5918 case IORING_OP_CONNECT:
bfe76559 5919 return io_connect_prep(req, sqe);
2d28390a 5920 case IORING_OP_TIMEOUT:
bfe76559 5921 return io_timeout_prep(req, sqe, false);
b29472ee 5922 case IORING_OP_TIMEOUT_REMOVE:
bfe76559 5923 return io_timeout_remove_prep(req, sqe);
fbf23849 5924 case IORING_OP_ASYNC_CANCEL:
bfe76559 5925 return io_async_cancel_prep(req, sqe);
2d28390a 5926 case IORING_OP_LINK_TIMEOUT:
bfe76559 5927 return io_timeout_prep(req, sqe, true);
8ed8d3c3 5928 case IORING_OP_ACCEPT:
bfe76559 5929 return io_accept_prep(req, sqe);
d63d1b5e 5930 case IORING_OP_FALLOCATE:
bfe76559 5931 return io_fallocate_prep(req, sqe);
15b71abe 5932 case IORING_OP_OPENAT:
bfe76559 5933 return io_openat_prep(req, sqe);
b5dba59e 5934 case IORING_OP_CLOSE:
bfe76559 5935 return io_close_prep(req, sqe);
05f3fb3c 5936 case IORING_OP_FILES_UPDATE:
269bbe5f 5937 return io_rsrc_update_prep(req, sqe);
eddc7ef5 5938 case IORING_OP_STATX:
bfe76559 5939 return io_statx_prep(req, sqe);
4840e418 5940 case IORING_OP_FADVISE:
bfe76559 5941 return io_fadvise_prep(req, sqe);
c1ca757b 5942 case IORING_OP_MADVISE:
bfe76559 5943 return io_madvise_prep(req, sqe);
cebdb986 5944 case IORING_OP_OPENAT2:
bfe76559 5945 return io_openat2_prep(req, sqe);
3e4827b0 5946 case IORING_OP_EPOLL_CTL:
bfe76559 5947 return io_epoll_ctl_prep(req, sqe);
7d67af2c 5948 case IORING_OP_SPLICE:
bfe76559 5949 return io_splice_prep(req, sqe);
ddf0322d 5950 case IORING_OP_PROVIDE_BUFFERS:
bfe76559 5951 return io_provide_buffers_prep(req, sqe);
067524e9 5952 case IORING_OP_REMOVE_BUFFERS:
bfe76559 5953 return io_remove_buffers_prep(req, sqe);
f2a8d5c7 5954 case IORING_OP_TEE:
bfe76559 5955 return io_tee_prep(req, sqe);
36f4fa68
JA
5956 case IORING_OP_SHUTDOWN:
5957 return io_shutdown_prep(req, sqe);
80a261fd
JA
5958 case IORING_OP_RENAMEAT:
5959 return io_renameat_prep(req, sqe);
14a1143b
JA
5960 case IORING_OP_UNLINKAT:
5961 return io_unlinkat_prep(req, sqe);
f67676d1
JA
5962 }
5963
bfe76559
PB
5964 printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
5965 req->opcode);
5966 return-EINVAL;
5967}
5968
93642ef8 5969static int io_req_prep_async(struct io_kiocb *req)
bfe76559 5970{
b7e298d2
PB
5971 if (!io_op_defs[req->opcode].needs_async_setup)
5972 return 0;
5973 if (WARN_ON_ONCE(req->async_data))
5974 return -EFAULT;
5975 if (io_alloc_async_data(req))
5976 return -EAGAIN;
5977
93642ef8
PB
5978 switch (req->opcode) {
5979 case IORING_OP_READV:
93642ef8
PB
5980 return io_rw_prep_async(req, READ);
5981 case IORING_OP_WRITEV:
93642ef8
PB
5982 return io_rw_prep_async(req, WRITE);
5983 case IORING_OP_SENDMSG:
93642ef8
PB
5984 return io_sendmsg_prep_async(req);
5985 case IORING_OP_RECVMSG:
93642ef8
PB
5986 return io_recvmsg_prep_async(req);
5987 case IORING_OP_CONNECT:
5988 return io_connect_prep_async(req);
5989 }
b7e298d2
PB
5990 printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n",
5991 req->opcode);
5992 return -EFAULT;
f67676d1
JA
5993}
5994
9cf7c104
PB
5995static u32 io_get_sequence(struct io_kiocb *req)
5996{
5997 struct io_kiocb *pos;
5998 struct io_ring_ctx *ctx = req->ctx;
f2f87370 5999 u32 total_submitted, nr_reqs = 0;
9cf7c104 6000
f2f87370
PB
6001 io_for_each_link(pos, req)
6002 nr_reqs++;
9cf7c104
PB
6003
6004 total_submitted = ctx->cached_sq_head - ctx->cached_sq_dropped;
6005 return total_submitted - nr_reqs;
6006}
6007
be7053b7 6008static int io_req_defer(struct io_kiocb *req)
de0617e4 6009{
a197f664 6010 struct io_ring_ctx *ctx = req->ctx;
27dc8338 6011 struct io_defer_entry *de;
f67676d1 6012 int ret;
9cf7c104 6013 u32 seq;
de0617e4 6014
9d858b21 6015 /* Still need defer if there is pending req in defer list. */
9cf7c104
PB
6016 if (likely(list_empty_careful(&ctx->defer_list) &&
6017 !(req->flags & REQ_F_IO_DRAIN)))
6018 return 0;
6019
6020 seq = io_get_sequence(req);
6021 /* Still a chance to pass the sequence check */
6022 if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
de0617e4
JA
6023 return 0;
6024
b7e298d2 6025 ret = io_req_prep_async(req);
be7053b7
PB
6026 if (ret)
6027 return ret;
cbdcb435 6028 io_prep_async_link(req);
27dc8338
PB
6029 de = kmalloc(sizeof(*de), GFP_KERNEL);
6030 if (!de)
6031 return -ENOMEM;
2d28390a 6032
de0617e4 6033 spin_lock_irq(&ctx->completion_lock);
9cf7c104 6034 if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
de0617e4 6035 spin_unlock_irq(&ctx->completion_lock);
27dc8338 6036 kfree(de);
ae34817b
PB
6037 io_queue_async_work(req);
6038 return -EIOCBQUEUED;
de0617e4
JA
6039 }
6040
915967f6 6041 trace_io_uring_defer(ctx, req, req->user_data);
27dc8338 6042 de->req = req;
9cf7c104 6043 de->seq = seq;
27dc8338 6044 list_add_tail(&de->list, &ctx->defer_list);
de0617e4
JA
6045 spin_unlock_irq(&ctx->completion_lock);
6046 return -EIOCBQUEUED;
6047}
6048
68fb8979 6049static void io_clean_op(struct io_kiocb *req)
99bc4c38 6050{
0e1b6fe3
PB
6051 if (req->flags & REQ_F_BUFFER_SELECTED) {
6052 switch (req->opcode) {
6053 case IORING_OP_READV:
6054 case IORING_OP_READ_FIXED:
6055 case IORING_OP_READ:
bcda7baa 6056 kfree((void *)(unsigned long)req->rw.addr);
0e1b6fe3
PB
6057 break;
6058 case IORING_OP_RECVMSG:
6059 case IORING_OP_RECV:
bcda7baa 6060 kfree(req->sr_msg.kbuf);
0e1b6fe3
PB
6061 break;
6062 }
6063 req->flags &= ~REQ_F_BUFFER_SELECTED;
99bc4c38
PB
6064 }
6065
0e1b6fe3
PB
6066 if (req->flags & REQ_F_NEED_CLEANUP) {
6067 switch (req->opcode) {
6068 case IORING_OP_READV:
6069 case IORING_OP_READ_FIXED:
6070 case IORING_OP_READ:
6071 case IORING_OP_WRITEV:
6072 case IORING_OP_WRITE_FIXED:
e8c2bc1f
JA
6073 case IORING_OP_WRITE: {
6074 struct io_async_rw *io = req->async_data;
6075 if (io->free_iovec)
6076 kfree(io->free_iovec);
0e1b6fe3 6077 break;
e8c2bc1f 6078 }
0e1b6fe3 6079 case IORING_OP_RECVMSG:
e8c2bc1f
JA
6080 case IORING_OP_SENDMSG: {
6081 struct io_async_msghdr *io = req->async_data;
257e84a5
PB
6082
6083 kfree(io->free_iov);
0e1b6fe3 6084 break;
e8c2bc1f 6085 }
0e1b6fe3
PB
6086 case IORING_OP_SPLICE:
6087 case IORING_OP_TEE:
e1d767f0
PB
6088 if (!(req->splice.flags & SPLICE_F_FD_IN_FIXED))
6089 io_put_file(req->splice.file_in);
0e1b6fe3 6090 break;
f3cd4850
JA
6091 case IORING_OP_OPENAT:
6092 case IORING_OP_OPENAT2:
6093 if (req->open.filename)
6094 putname(req->open.filename);
6095 break;
80a261fd
JA
6096 case IORING_OP_RENAMEAT:
6097 putname(req->rename.oldpath);
6098 putname(req->rename.newpath);
6099 break;
14a1143b
JA
6100 case IORING_OP_UNLINKAT:
6101 putname(req->unlink.filename);
6102 break;
0e1b6fe3
PB
6103 }
6104 req->flags &= ~REQ_F_NEED_CLEANUP;
99bc4c38 6105 }
99bc4c38
PB
6106}
6107
889fca73 6108static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
2b188cc1 6109{
a197f664 6110 struct io_ring_ctx *ctx = req->ctx;
5730b27e 6111 const struct cred *creds = NULL;
d625c6ee 6112 int ret;
2b188cc1 6113
003e8dcc
JA
6114 if (req->work.creds && req->work.creds != current_cred())
6115 creds = override_creds(req->work.creds);
5730b27e 6116
d625c6ee 6117 switch (req->opcode) {
2b188cc1 6118 case IORING_OP_NOP:
889fca73 6119 ret = io_nop(req, issue_flags);
2b188cc1
JA
6120 break;
6121 case IORING_OP_READV:
edafccee 6122 case IORING_OP_READ_FIXED:
3a6820f2 6123 case IORING_OP_READ:
889fca73 6124 ret = io_read(req, issue_flags);
edafccee 6125 break;
3529d8c2 6126 case IORING_OP_WRITEV:
edafccee 6127 case IORING_OP_WRITE_FIXED:
3a6820f2 6128 case IORING_OP_WRITE:
889fca73 6129 ret = io_write(req, issue_flags);
2b188cc1 6130 break;
c992fe29 6131 case IORING_OP_FSYNC:
45d189c6 6132 ret = io_fsync(req, issue_flags);
c992fe29 6133 break;
221c5eb2 6134 case IORING_OP_POLL_ADD:
61e98203 6135 ret = io_poll_add(req, issue_flags);
221c5eb2
JA
6136 break;
6137 case IORING_OP_POLL_REMOVE:
61e98203 6138 ret = io_poll_remove(req, issue_flags);
221c5eb2 6139 break;
5d17b4a4 6140 case IORING_OP_SYNC_FILE_RANGE:
45d189c6 6141 ret = io_sync_file_range(req, issue_flags);
5d17b4a4 6142 break;
0fa03c62 6143 case IORING_OP_SENDMSG:
889fca73 6144 ret = io_sendmsg(req, issue_flags);
062d04d7 6145 break;
fddaface 6146 case IORING_OP_SEND:
889fca73 6147 ret = io_send(req, issue_flags);
0fa03c62 6148 break;
aa1fa28f 6149 case IORING_OP_RECVMSG:
889fca73 6150 ret = io_recvmsg(req, issue_flags);
062d04d7 6151 break;
fddaface 6152 case IORING_OP_RECV:
889fca73 6153 ret = io_recv(req, issue_flags);
aa1fa28f 6154 break;
5262f567 6155 case IORING_OP_TIMEOUT:
61e98203 6156 ret = io_timeout(req, issue_flags);
5262f567 6157 break;
11365043 6158 case IORING_OP_TIMEOUT_REMOVE:
61e98203 6159 ret = io_timeout_remove(req, issue_flags);
11365043 6160 break;
17f2fe35 6161 case IORING_OP_ACCEPT:
889fca73 6162 ret = io_accept(req, issue_flags);
17f2fe35 6163 break;
f8e85cf2 6164 case IORING_OP_CONNECT:
889fca73 6165 ret = io_connect(req, issue_flags);
f8e85cf2 6166 break;
62755e35 6167 case IORING_OP_ASYNC_CANCEL:
61e98203 6168 ret = io_async_cancel(req, issue_flags);
62755e35 6169 break;
d63d1b5e 6170 case IORING_OP_FALLOCATE:
45d189c6 6171 ret = io_fallocate(req, issue_flags);
d63d1b5e 6172 break;
15b71abe 6173 case IORING_OP_OPENAT:
45d189c6 6174 ret = io_openat(req, issue_flags);
15b71abe 6175 break;
b5dba59e 6176 case IORING_OP_CLOSE:
889fca73 6177 ret = io_close(req, issue_flags);
b5dba59e 6178 break;
05f3fb3c 6179 case IORING_OP_FILES_UPDATE:
889fca73 6180 ret = io_files_update(req, issue_flags);
05f3fb3c 6181 break;
eddc7ef5 6182 case IORING_OP_STATX:
45d189c6 6183 ret = io_statx(req, issue_flags);
eddc7ef5 6184 break;
4840e418 6185 case IORING_OP_FADVISE:
45d189c6 6186 ret = io_fadvise(req, issue_flags);
4840e418 6187 break;
c1ca757b 6188 case IORING_OP_MADVISE:
45d189c6 6189 ret = io_madvise(req, issue_flags);
c1ca757b 6190 break;
cebdb986 6191 case IORING_OP_OPENAT2:
45d189c6 6192 ret = io_openat2(req, issue_flags);
cebdb986 6193 break;
3e4827b0 6194 case IORING_OP_EPOLL_CTL:
889fca73 6195 ret = io_epoll_ctl(req, issue_flags);
3e4827b0 6196 break;
7d67af2c 6197 case IORING_OP_SPLICE:
45d189c6 6198 ret = io_splice(req, issue_flags);
7d67af2c 6199 break;
ddf0322d 6200 case IORING_OP_PROVIDE_BUFFERS:
889fca73 6201 ret = io_provide_buffers(req, issue_flags);
ddf0322d 6202 break;
067524e9 6203 case IORING_OP_REMOVE_BUFFERS:
889fca73 6204 ret = io_remove_buffers(req, issue_flags);
3e4827b0 6205 break;
f2a8d5c7 6206 case IORING_OP_TEE:
45d189c6 6207 ret = io_tee(req, issue_flags);
f2a8d5c7 6208 break;
36f4fa68 6209 case IORING_OP_SHUTDOWN:
45d189c6 6210 ret = io_shutdown(req, issue_flags);
36f4fa68 6211 break;
80a261fd 6212 case IORING_OP_RENAMEAT:
45d189c6 6213 ret = io_renameat(req, issue_flags);
80a261fd 6214 break;
14a1143b 6215 case IORING_OP_UNLINKAT:
45d189c6 6216 ret = io_unlinkat(req, issue_flags);
14a1143b 6217 break;
2b188cc1
JA
6218 default:
6219 ret = -EINVAL;
6220 break;
6221 }
6222
5730b27e
JA
6223 if (creds)
6224 revert_creds(creds);
6225
def596e9
JA
6226 if (ret)
6227 return ret;
6228
b532576e
JA
6229 /* If the op doesn't have a file, we're not polling for it */
6230 if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file) {
11ba820b
JA
6231 const bool in_async = io_wq_current_is_worker();
6232
11ba820b
JA
6233 /* workqueue context doesn't hold uring_lock, grab it now */
6234 if (in_async)
6235 mutex_lock(&ctx->uring_lock);
6236
2e9dbe90 6237 io_iopoll_req_issued(req, in_async);
11ba820b
JA
6238
6239 if (in_async)
6240 mutex_unlock(&ctx->uring_lock);
def596e9
JA
6241 }
6242
6243 return 0;
2b188cc1
JA
6244}
6245
5280f7e5 6246static void io_wq_submit_work(struct io_wq_work *work)
2b188cc1
JA
6247{
6248 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
6df1db6b 6249 struct io_kiocb *timeout;
561fb04a 6250 int ret = 0;
2b188cc1 6251
6df1db6b
PB
6252 timeout = io_prep_linked_timeout(req);
6253 if (timeout)
6254 io_queue_linked_timeout(timeout);
d4c81f38 6255
4014d943 6256 if (work->flags & IO_WQ_WORK_CANCEL)
561fb04a 6257 ret = -ECANCELED;
31b51510 6258
561fb04a 6259 if (!ret) {
561fb04a 6260 do {
889fca73 6261 ret = io_issue_sqe(req, 0);
561fb04a
JA
6262 /*
6263 * We can get EAGAIN for polled IO even though we're
6264 * forcing a sync submission from here, since we can't
6265 * wait for request slots on the block side.
6266 */
6267 if (ret != -EAGAIN)
6268 break;
6269 cond_resched();
6270 } while (1);
6271 }
31b51510 6272
a3df7698 6273 /* avoid locking problems by failing it from a clean context */
561fb04a 6274 if (ret) {
a3df7698 6275 /* io-wq is going to take one down */
de9b4cca 6276 req_ref_get(req);
a3df7698 6277 io_req_task_queue_fail(req, ret);
edafccee 6278 }
2b188cc1
JA
6279}
6280
7b29f92d
JA
6281#define FFS_ASYNC_READ 0x1UL
6282#define FFS_ASYNC_WRITE 0x2UL
6283#ifdef CONFIG_64BIT
6284#define FFS_ISREG 0x4UL
6285#else
6286#define FFS_ISREG 0x0UL
6287#endif
6288#define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
6289
dafecf19
PB
6290static inline struct file **io_fixed_file_slot(struct fixed_rsrc_data *file_data,
6291 unsigned i)
65e19f54 6292{
269bbe5f 6293 struct fixed_rsrc_table *table;
65e19f54 6294
dafecf19
PB
6295 table = &file_data->table[i >> IORING_FILE_TABLE_SHIFT];
6296 return &table->files[i & IORING_FILE_TABLE_MASK];
6297}
6298
6299static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
6300 int index)
6301{
7b29f92d
JA
6302 struct file **file_slot = io_fixed_file_slot(ctx->file_data, index);
6303
6304 return (struct file *) ((unsigned long) *file_slot & FFS_MASK);
65e19f54
JA
6305}
6306
8371adf5
PB
6307static struct file *io_file_get(struct io_submit_state *state,
6308 struct io_kiocb *req, int fd, bool fixed)
09bb8394 6309{
a197f664 6310 struct io_ring_ctx *ctx = req->ctx;
8da11c19 6311 struct file *file;
09bb8394 6312
8da11c19 6313 if (fixed) {
7b29f92d
JA
6314 unsigned long file_ptr;
6315
479f517b 6316 if (unlikely((unsigned int)fd >= ctx->nr_user_files))
8371adf5 6317 return NULL;
b7620121 6318 fd = array_index_nospec(fd, ctx->nr_user_files);
7b29f92d
JA
6319 file_ptr = (unsigned long) *io_fixed_file_slot(ctx->file_data, fd);
6320 file = (struct file *) (file_ptr & FFS_MASK);
6321 file_ptr &= ~FFS_MASK;
6322 /* mask in overlapping REQ_F and FFS bits */
6323 req->flags |= (file_ptr << REQ_F_ASYNC_READ_BIT);
36f72fe2 6324 io_set_resource_node(req);
09bb8394 6325 } else {
c826bd7a 6326 trace_io_uring_file_get(ctx, fd);
8da11c19 6327 file = __io_file_get(state, fd);
d44f554e
JA
6328
6329 /* we don't allow fixed io_uring files */
6330 if (file && unlikely(file->f_op == &io_uring_fops))
6331 io_req_track_inflight(req);
09bb8394
JA
6332 }
6333
8371adf5 6334 return file;
09bb8394
JA
6335}
6336
2665abfd 6337static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
2b188cc1 6338{
ad8a48ac
JA
6339 struct io_timeout_data *data = container_of(timer,
6340 struct io_timeout_data, timer);
90cd7e42 6341 struct io_kiocb *prev, *req = data->req;
2665abfd 6342 struct io_ring_ctx *ctx = req->ctx;
2665abfd 6343 unsigned long flags;
2665abfd
JA
6344
6345 spin_lock_irqsave(&ctx->completion_lock, flags);
90cd7e42
PB
6346 prev = req->timeout.head;
6347 req->timeout.head = NULL;
2665abfd
JA
6348
6349 /*
6350 * We don't expect the list to be empty, that will only happen if we
6351 * race with the completion of the linked work.
6352 */
de9b4cca 6353 if (prev && req_ref_inc_not_zero(prev))
f2f87370 6354 io_remove_next_linked(prev);
90cd7e42
PB
6355 else
6356 prev = NULL;
2665abfd
JA
6357 spin_unlock_irqrestore(&ctx->completion_lock, flags);
6358
6359 if (prev) {
014db007 6360 io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME);
9ae1f8dd 6361 io_put_req_deferred(prev, 1);
47f46768 6362 } else {
9ae1f8dd
PB
6363 io_req_complete_post(req, -ETIME, 0);
6364 io_put_req_deferred(req, 1);
2665abfd 6365 }
2665abfd
JA
6366 return HRTIMER_NORESTART;
6367}
6368
de968c18 6369static void io_queue_linked_timeout(struct io_kiocb *req)
2665abfd 6370{
de968c18
PB
6371 struct io_ring_ctx *ctx = req->ctx;
6372
6373 spin_lock_irq(&ctx->completion_lock);
76a46e06 6374 /*
f2f87370
PB
6375 * If the back reference is NULL, then our linked request finished
6376 * before we got a chance to setup the timer
76a46e06 6377 */
90cd7e42 6378 if (req->timeout.head) {
e8c2bc1f 6379 struct io_timeout_data *data = req->async_data;
94ae5e77 6380
ad8a48ac
JA
6381 data->timer.function = io_link_timeout_fn;
6382 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
6383 data->mode);
2665abfd 6384 }
76a46e06 6385 spin_unlock_irq(&ctx->completion_lock);
2665abfd 6386 /* drop submission reference */
76a46e06
JA
6387 io_put_req(req);
6388}
2665abfd 6389
ad8a48ac 6390static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
2665abfd 6391{
f2f87370 6392 struct io_kiocb *nxt = req->link;
2665abfd 6393
f2f87370
PB
6394 if (!nxt || (req->flags & REQ_F_LINK_TIMEOUT) ||
6395 nxt->opcode != IORING_OP_LINK_TIMEOUT)
76a46e06 6396 return NULL;
2665abfd 6397
90cd7e42 6398 nxt->timeout.head = req;
900fad45 6399 nxt->flags |= REQ_F_LTIMEOUT_ACTIVE;
76a46e06 6400 req->flags |= REQ_F_LINK_TIMEOUT;
76a46e06 6401 return nxt;
2665abfd
JA
6402}
6403
c5eef2b9 6404static void __io_queue_sqe(struct io_kiocb *req)
2b188cc1 6405{
d3d7298d 6406 struct io_kiocb *linked_timeout = io_prep_linked_timeout(req);
e0c5c576 6407 int ret;
2b188cc1 6408
c5eef2b9 6409 ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
193155c8 6410
491381ce
JA
6411 /*
6412 * We async punt it if the file wasn't marked NOWAIT, or if the file
6413 * doesn't support non-blocking read/write attempts
6414 */
1840038e 6415 if (likely(!ret)) {
0d63c148 6416 /* drop submission reference */
e342c807 6417 if (req->flags & REQ_F_COMPLETE_INLINE) {
c5eef2b9
PB
6418 struct io_ring_ctx *ctx = req->ctx;
6419 struct io_comp_state *cs = &ctx->submit_state.comp;
e65ef56d 6420
6dd0be1e 6421 cs->reqs[cs->nr++] = req;
d3d7298d 6422 if (cs->nr == ARRAY_SIZE(cs->reqs))
c5eef2b9 6423 io_submit_flush_completions(cs, ctx);
9affd664 6424 } else {
d3d7298d 6425 io_put_req(req);
0d63c148 6426 }
1840038e
PB
6427 } else if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
6428 if (!io_arm_poll_handler(req)) {
6429 /*
6430 * Queued up for async execution, worker will release
6431 * submit reference when the iocb is actually submitted.
6432 */
6433 io_queue_async_work(req);
6434 }
0d63c148 6435 } else {
f41db273 6436 io_req_complete_failed(req, ret);
9e645e11 6437 }
d3d7298d
PB
6438 if (linked_timeout)
6439 io_queue_linked_timeout(linked_timeout);
2b188cc1
JA
6440}
6441
be7053b7 6442static void io_queue_sqe(struct io_kiocb *req)
4fe2c963
JL
6443{
6444 int ret;
6445
be7053b7 6446 ret = io_req_defer(req);
4fe2c963
JL
6447 if (ret) {
6448 if (ret != -EIOCBQUEUED) {
1118591a 6449fail_req:
f41db273 6450 io_req_complete_failed(req, ret);
4fe2c963 6451 }
2550878f 6452 } else if (req->flags & REQ_F_FORCE_ASYNC) {
b7e298d2 6453 ret = io_req_prep_async(req);
be7053b7
PB
6454 if (unlikely(ret))
6455 goto fail_req;
ce35a47a
JA
6456 io_queue_async_work(req);
6457 } else {
c5eef2b9 6458 __io_queue_sqe(req);
ce35a47a 6459 }
4fe2c963
JL
6460}
6461
b16fed66
PB
6462/*
6463 * Check SQE restrictions (opcode and flags).
6464 *
6465 * Returns 'true' if SQE is allowed, 'false' otherwise.
6466 */
6467static inline bool io_check_restriction(struct io_ring_ctx *ctx,
6468 struct io_kiocb *req,
6469 unsigned int sqe_flags)
4fe2c963 6470{
b16fed66
PB
6471 if (!ctx->restricted)
6472 return true;
6473
6474 if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
6475 return false;
6476
6477 if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
6478 ctx->restrictions.sqe_flags_required)
6479 return false;
6480
6481 if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
6482 ctx->restrictions.sqe_flags_required))
6483 return false;
6484
6485 return true;
4fe2c963
JL
6486}
6487
b16fed66
PB
6488static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
6489 const struct io_uring_sqe *sqe)
6490{
6491 struct io_submit_state *state;
6492 unsigned int sqe_flags;
003e8dcc 6493 int personality, ret = 0;
b16fed66
PB
6494
6495 req->opcode = READ_ONCE(sqe->opcode);
6496 /* same numerical values with corresponding REQ_F_*, safe to copy */
6497 req->flags = sqe_flags = READ_ONCE(sqe->flags);
6498 req->user_data = READ_ONCE(sqe->user_data);
6499 req->async_data = NULL;
6500 req->file = NULL;
6501 req->ctx = ctx;
6502 req->link = NULL;
6503 req->fixed_rsrc_refs = NULL;
6504 /* one is dropped after submission, the other at completion */
abc54d63 6505 atomic_set(&req->refs, 2);
b16fed66
PB
6506 req->task = current;
6507 req->result = 0;
93e68e03 6508 req->work.creds = NULL;
b16fed66
PB
6509
6510 /* enforce forwards compatibility on users */
ebf4a5db
PB
6511 if (unlikely(sqe_flags & ~SQE_VALID_FLAGS)) {
6512 req->flags = 0;
b16fed66 6513 return -EINVAL;
ebf4a5db 6514 }
b16fed66
PB
6515
6516 if (unlikely(req->opcode >= IORING_OP_LAST))
6517 return -EINVAL;
6518
b16fed66
PB
6519 if (unlikely(!io_check_restriction(ctx, req, sqe_flags)))
6520 return -EACCES;
6521
6522 if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
6523 !io_op_defs[req->opcode].buffer_select)
6524 return -EOPNOTSUPP;
863e0560 6525
003e8dcc
JA
6526 personality = READ_ONCE(sqe->personality);
6527 if (personality) {
61cf9370 6528 req->work.creds = xa_load(&ctx->personalities, personality);
003e8dcc
JA
6529 if (!req->work.creds)
6530 return -EINVAL;
6531 get_cred(req->work.creds);
003e8dcc 6532 }
b16fed66
PB
6533 state = &ctx->submit_state;
6534
6535 /*
6536 * Plug now if we have more than 1 IO left after this, and the target
6537 * is potentially a read/write to block based storage.
6538 */
6539 if (!state->plug_started && state->ios_left > 1 &&
6540 io_op_defs[req->opcode].plug) {
6541 blk_start_plug(&state->plug);
6542 state->plug_started = true;
6543 }
6544
6545 if (io_op_defs[req->opcode].needs_file) {
6546 bool fixed = req->flags & REQ_F_FIXED_FILE;
6547
6548 req->file = io_file_get(state, req, READ_ONCE(sqe->fd), fixed);
6549 if (unlikely(!req->file))
6550 ret = -EBADF;
6551 }
6552
6553 state->ios_left--;
6554 return ret;
6555}
6556
a6b8cadc 6557static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
a1ab7b35 6558 const struct io_uring_sqe *sqe)
9e645e11 6559{
a1ab7b35 6560 struct io_submit_link *link = &ctx->submit_state.link;
ef4ff581 6561 int ret;
9e645e11 6562
a6b8cadc
PB
6563 ret = io_init_req(ctx, req, sqe);
6564 if (unlikely(ret)) {
6565fail_req:
de59bc10
PB
6566 if (link->head) {
6567 /* fail even hard links since we don't submit */
cf109604 6568 link->head->flags |= REQ_F_FAIL_LINK;
f41db273 6569 io_req_complete_failed(link->head, -ECANCELED);
de59bc10
PB
6570 link->head = NULL;
6571 }
f41db273 6572 io_req_complete_failed(req, ret);
a6b8cadc
PB
6573 return ret;
6574 }
be7053b7
PB
6575 ret = io_req_prep(req, sqe);
6576 if (unlikely(ret))
6577 goto fail_req;
a6b8cadc 6578
be7053b7 6579 /* don't need @sqe from now on */
a6b8cadc
PB
6580 trace_io_uring_submit_sqe(ctx, req->opcode, req->user_data,
6581 true, ctx->flags & IORING_SETUP_SQPOLL);
6582
9e645e11
JA
6583 /*
6584 * If we already have a head request, queue this one for async
6585 * submittal once the head completes. If we don't have a head but
6586 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6587 * submitted sync once the chain is complete. If none of those
6588 * conditions are true (normal request), then just queue it.
6589 */
863e0560
PB
6590 if (link->head) {
6591 struct io_kiocb *head = link->head;
4e88d6e7 6592
8cdf2193
PB
6593 /*
6594 * Taking sequential execution of a link, draining both sides
6595 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6596 * requests in the link. So, it drains the head and the
6597 * next after the link request. The last one is done via
6598 * drain_next flag to persist the effect across calls.
6599 */
ef4ff581 6600 if (req->flags & REQ_F_IO_DRAIN) {
711be031
PB
6601 head->flags |= REQ_F_IO_DRAIN;
6602 ctx->drain_next = 1;
6603 }
b7e298d2 6604 ret = io_req_prep_async(req);
cf109604 6605 if (unlikely(ret))
a6b8cadc 6606 goto fail_req;
9d76377f 6607 trace_io_uring_link(ctx, req, head);
f2f87370 6608 link->last->link = req;
863e0560 6609 link->last = req;
32fe525b
PB
6610
6611 /* last request of a link, enqueue the link */
ef4ff581 6612 if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
de59bc10 6613 io_queue_sqe(head);
863e0560 6614 link->head = NULL;
32fe525b 6615 }
9e645e11 6616 } else {
711be031
PB
6617 if (unlikely(ctx->drain_next)) {
6618 req->flags |= REQ_F_IO_DRAIN;
ef4ff581 6619 ctx->drain_next = 0;
711be031 6620 }
ef4ff581 6621 if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
863e0560
PB
6622 link->head = req;
6623 link->last = req;
711be031 6624 } else {
be7053b7 6625 io_queue_sqe(req);
711be031 6626 }
9e645e11 6627 }
2e6e1fde 6628
1d4240cc 6629 return 0;
9e645e11
JA
6630}
6631
9a56a232
JA
6632/*
6633 * Batched submission is done, ensure local IO is flushed out.
6634 */
ba88ff11
PB
6635static void io_submit_state_end(struct io_submit_state *state,
6636 struct io_ring_ctx *ctx)
9a56a232 6637{
a1ab7b35 6638 if (state->link.head)
de59bc10 6639 io_queue_sqe(state->link.head);
6dd0be1e 6640 if (state->comp.nr)
ba88ff11 6641 io_submit_flush_completions(&state->comp, ctx);
27926b68
JA
6642 if (state->plug_started)
6643 blk_finish_plug(&state->plug);
9f13c35b 6644 io_state_file_put(state);
9a56a232
JA
6645}
6646
6647/*
6648 * Start submission side cache.
6649 */
6650static void io_submit_state_start(struct io_submit_state *state,
ba88ff11 6651 unsigned int max_ios)
9a56a232 6652{
27926b68 6653 state->plug_started = false;
9a56a232 6654 state->ios_left = max_ios;
a1ab7b35
PB
6655 /* set only head, no need to init link_last in advance */
6656 state->link.head = NULL;
9a56a232
JA
6657}
6658
2b188cc1
JA
6659static void io_commit_sqring(struct io_ring_ctx *ctx)
6660{
75b28aff 6661 struct io_rings *rings = ctx->rings;
2b188cc1 6662
caf582c6
PB
6663 /*
6664 * Ensure any loads from the SQEs are done at this point,
6665 * since once we write the new head, the application could
6666 * write new data to them.
6667 */
6668 smp_store_release(&rings->sq.head, ctx->cached_sq_head);
2b188cc1
JA
6669}
6670
2b188cc1 6671/*
3529d8c2 6672 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
2b188cc1
JA
6673 * that is mapped by userspace. This means that care needs to be taken to
6674 * ensure that reads are stable, as we cannot rely on userspace always
6675 * being a good citizen. If members of the sqe are validated and then later
6676 * used, it's important that those reads are done through READ_ONCE() to
6677 * prevent a re-load down the line.
6678 */
709b302f 6679static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
2b188cc1 6680{
75b28aff 6681 u32 *sq_array = ctx->sq_array;
2b188cc1
JA
6682 unsigned head;
6683
6684 /*
6685 * The cached sq head (or cq tail) serves two purposes:
6686 *
6687 * 1) allows us to batch the cost of updating the user visible
6688 * head updates.
6689 * 2) allows the kernel side to track the head on its own, even
6690 * though the application is the one updating it.
6691 */
4fccfcbb 6692 head = READ_ONCE(sq_array[ctx->cached_sq_head++ & ctx->sq_mask]);
709b302f
PB
6693 if (likely(head < ctx->sq_entries))
6694 return &ctx->sq_sqes[head];
2b188cc1
JA
6695
6696 /* drop invalid entries */
498ccd9e 6697 ctx->cached_sq_dropped++;
ee7d46d9 6698 WRITE_ONCE(ctx->rings->sq_dropped, ctx->cached_sq_dropped);
709b302f
PB
6699 return NULL;
6700}
6701
0f212204 6702static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
6c271ce2 6703{
46c4e16a 6704 int submitted = 0;
6c271ce2 6705
c4a2ed72 6706 /* if we have a backlog and couldn't flush it all, return BUSY */
ad3eb2c8 6707 if (test_bit(0, &ctx->sq_check_overflow)) {
6c2450ae 6708 if (!__io_cqring_overflow_flush(ctx, false))
ad3eb2c8
JA
6709 return -EBUSY;
6710 }
6c271ce2 6711
ee7d46d9
PB
6712 /* make sure SQ entry isn't read before tail */
6713 nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
9ef4f124 6714
2b85edfc
PB
6715 if (!percpu_ref_tryget_many(&ctx->refs, nr))
6716 return -EAGAIN;
6c271ce2 6717
d8a6df10 6718 percpu_counter_add(&current->io_uring->inflight, nr);
faf7b51c 6719 refcount_add(nr, &current->usage);
ba88ff11 6720 io_submit_state_start(&ctx->submit_state, nr);
b14cca0c 6721
46c4e16a 6722 while (submitted < nr) {
3529d8c2 6723 const struct io_uring_sqe *sqe;
196be95c 6724 struct io_kiocb *req;
fb5ccc98 6725
258b29a9 6726 req = io_alloc_req(ctx);
196be95c
PB
6727 if (unlikely(!req)) {
6728 if (!submitted)
6729 submitted = -EAGAIN;
fb5ccc98 6730 break;
196be95c 6731 }
4fccfcbb
PB
6732 sqe = io_get_sqe(ctx);
6733 if (unlikely(!sqe)) {
6734 kmem_cache_free(req_cachep, req);
6735 break;
6736 }
d3656344
JA
6737 /* will complete beyond this point, count as submitted */
6738 submitted++;
a1ab7b35 6739 if (io_submit_sqe(ctx, req, sqe))
196be95c 6740 break;
6c271ce2
JA
6741 }
6742
9466f437
PB
6743 if (unlikely(submitted != nr)) {
6744 int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
d8a6df10
JA
6745 struct io_uring_task *tctx = current->io_uring;
6746 int unused = nr - ref_used;
9466f437 6747
d8a6df10
JA
6748 percpu_ref_put_many(&ctx->refs, unused);
6749 percpu_counter_sub(&tctx->inflight, unused);
6750 put_task_struct_many(current, unused);
9466f437 6751 }
6c271ce2 6752
a1ab7b35 6753 io_submit_state_end(&ctx->submit_state, ctx);
ae9428ca
PB
6754 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6755 io_commit_sqring(ctx);
6756
6c271ce2
JA
6757 return submitted;
6758}
6759
23b3628e
XW
6760static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
6761{
6762 /* Tell userspace we may need a wakeup call */
6763 spin_lock_irq(&ctx->completion_lock);
6764 ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP;
6765 spin_unlock_irq(&ctx->completion_lock);
6766}
6767
6768static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
6769{
6770 spin_lock_irq(&ctx->completion_lock);
6771 ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
6772 spin_unlock_irq(&ctx->completion_lock);
6773}
6774
08369246 6775static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
6c271ce2 6776{
c8d1ba58 6777 unsigned int to_submit;
bdcd3eab 6778 int ret = 0;
6c271ce2 6779
c8d1ba58 6780 to_submit = io_sqring_entries(ctx);
e95eee2d
JA
6781 /* if we're handling multiple rings, cap submit size for fairness */
6782 if (cap_entries && to_submit > 8)
6783 to_submit = 8;
6784
906a3c6f 6785 if (!list_empty(&ctx->iopoll_list) || to_submit) {
c8d1ba58 6786 unsigned nr_events = 0;
a4c0b3de 6787
c8d1ba58 6788 mutex_lock(&ctx->uring_lock);
906a3c6f 6789 if (!list_empty(&ctx->iopoll_list))
c8d1ba58 6790 io_do_iopoll(ctx, &nr_events, 0);
906a3c6f 6791
0298ef96
PB
6792 if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
6793 !(ctx->flags & IORING_SETUP_R_DISABLED))
08369246 6794 ret = io_submit_sqes(ctx, to_submit);
c8d1ba58
JA
6795 mutex_unlock(&ctx->uring_lock);
6796 }
6c271ce2 6797
90554200
JA
6798 if (!io_sqring_full(ctx) && wq_has_sleeper(&ctx->sqo_sq_wait))
6799 wake_up(&ctx->sqo_sq_wait);
6c271ce2 6800
08369246
XW
6801 return ret;
6802}
6c271ce2 6803
08369246
XW
6804static void io_sqd_update_thread_idle(struct io_sq_data *sqd)
6805{
6806 struct io_ring_ctx *ctx;
6807 unsigned sq_thread_idle = 0;
6c271ce2 6808
c9dca27d
PB
6809 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6810 sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle);
08369246 6811 sqd->sq_thread_idle = sq_thread_idle;
c8d1ba58 6812}
6c271ce2 6813
c8d1ba58
JA
6814static int io_sq_thread(void *data)
6815{
69fb2131
JA
6816 struct io_sq_data *sqd = data;
6817 struct io_ring_ctx *ctx;
a0d9205f 6818 unsigned long timeout = 0;
37d1e2e3 6819 char buf[TASK_COMM_LEN];
08369246 6820 DEFINE_WAIT(wait);
6c271ce2 6821
696ee88a 6822 snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
37d1e2e3 6823 set_task_comm(current, buf);
37d1e2e3
JA
6824 current->pf_io_worker = NULL;
6825
6826 if (sqd->sq_cpu != -1)
6827 set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
6828 else
6829 set_cpus_allowed_ptr(current, cpu_online_mask);
6830 current->flags |= PF_NO_SETAFFINITY;
6831
09a6f4ef 6832 mutex_lock(&sqd->lock);
05962f95 6833 while (!test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state)) {
08369246
XW
6834 int ret;
6835 bool cap_entries, sqt_spin, needs_sched;
c1edbf5f 6836
82734c5b
JA
6837 if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
6838 signal_pending(current)) {
6839 bool did_sig = false;
6840
09a6f4ef 6841 mutex_unlock(&sqd->lock);
82734c5b
JA
6842 if (signal_pending(current)) {
6843 struct ksignal ksig;
6844
6845 did_sig = get_signal(&ksig);
6846 }
05962f95 6847 cond_resched();
09a6f4ef 6848 mutex_lock(&sqd->lock);
82734c5b
JA
6849 if (did_sig)
6850 break;
521d6a73 6851 io_run_task_work();
b7f5a0bf 6852 io_run_task_work_head(&sqd->park_task_work);
08369246 6853 timeout = jiffies + sqd->sq_thread_idle;
7d41e854 6854 continue;
08369246 6855 }
08369246 6856 sqt_spin = false;
e95eee2d 6857 cap_entries = !list_is_singular(&sqd->ctx_list);
69fb2131 6858 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
7c30f36a
SM
6859 const struct cred *creds = NULL;
6860
6861 if (ctx->sq_creds != current_cred())
6862 creds = override_creds(ctx->sq_creds);
08369246 6863 ret = __io_sq_thread(ctx, cap_entries);
7c30f36a
SM
6864 if (creds)
6865 revert_creds(creds);
08369246
XW
6866 if (!sqt_spin && (ret > 0 || !list_empty(&ctx->iopoll_list)))
6867 sqt_spin = true;
69fb2131 6868 }
6c271ce2 6869
08369246 6870 if (sqt_spin || !time_after(jiffies, timeout)) {
c8d1ba58
JA
6871 io_run_task_work();
6872 cond_resched();
08369246
XW
6873 if (sqt_spin)
6874 timeout = jiffies + sqd->sq_thread_idle;
6875 continue;
6876 }
6877
08369246
XW
6878 needs_sched = true;
6879 prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
6880 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
6881 if ((ctx->flags & IORING_SETUP_IOPOLL) &&
6882 !list_empty_careful(&ctx->iopoll_list)) {
6883 needs_sched = false;
6884 break;
6885 }
6886 if (io_sqring_entries(ctx)) {
6887 needs_sched = false;
6888 break;
6889 }
6890 }
6891
05962f95 6892 if (needs_sched && !test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state)) {
69fb2131
JA
6893 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6894 io_ring_set_wakeup_flag(ctx);
08369246 6895
09a6f4ef 6896 mutex_unlock(&sqd->lock);
69fb2131 6897 schedule();
09a6f4ef 6898 mutex_lock(&sqd->lock);
69fb2131
JA
6899 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6900 io_ring_clear_wakeup_flag(ctx);
6c271ce2 6901 }
08369246
XW
6902
6903 finish_wait(&sqd->wait, &wait);
b7f5a0bf 6904 io_run_task_work_head(&sqd->park_task_work);
08369246 6905 timeout = jiffies + sqd->sq_thread_idle;
6c271ce2 6906 }
28cea78a 6907
521d6a73
PB
6908 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6909 io_uring_cancel_sqpoll(ctx);
37d1e2e3 6910 sqd->thread = NULL;
05962f95 6911 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
5f3f26f9 6912 io_ring_set_wakeup_flag(ctx);
09a6f4ef 6913 mutex_unlock(&sqd->lock);
521d6a73
PB
6914
6915 io_run_task_work();
b7f5a0bf 6916 io_run_task_work_head(&sqd->park_task_work);
37d1e2e3
JA
6917 complete(&sqd->exited);
6918 do_exit(0);
6c271ce2
JA
6919}
6920
bda52162
JA
6921struct io_wait_queue {
6922 struct wait_queue_entry wq;
6923 struct io_ring_ctx *ctx;
6924 unsigned to_wait;
6925 unsigned nr_timeouts;
6926};
6927
6c503150 6928static inline bool io_should_wake(struct io_wait_queue *iowq)
bda52162
JA
6929{
6930 struct io_ring_ctx *ctx = iowq->ctx;
6931
6932 /*
d195a66e 6933 * Wake up if we have enough events, or if a timeout occurred since we
bda52162
JA
6934 * started waiting. For timeouts, we always want to return to userspace,
6935 * regardless of event count.
6936 */
6c503150 6937 return io_cqring_events(ctx) >= iowq->to_wait ||
bda52162
JA
6938 atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
6939}
6940
6941static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
6942 int wake_flags, void *key)
6943{
6944 struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
6945 wq);
6946
6c503150
PB
6947 /*
6948 * Cannot safely flush overflowed CQEs from here, ensure we wake up
6949 * the task, and the next invocation will do it.
6950 */
6951 if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->cq_check_overflow))
6952 return autoremove_wake_function(curr, mode, wake_flags, key);
6953 return -1;
bda52162
JA
6954}
6955
af9c1a44
JA
6956static int io_run_task_work_sig(void)
6957{
6958 if (io_run_task_work())
6959 return 1;
6960 if (!signal_pending(current))
6961 return 0;
0b8cfa97 6962 if (test_thread_flag(TIF_NOTIFY_SIGNAL))
792ee0f6 6963 return -ERESTARTSYS;
af9c1a44
JA
6964 return -EINTR;
6965}
6966
eeb60b9a
PB
6967/* when returns >0, the caller should retry */
6968static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
6969 struct io_wait_queue *iowq,
6970 signed long *timeout)
6971{
6972 int ret;
6973
6974 /* make sure we run task_work before checking for signals */
6975 ret = io_run_task_work_sig();
6976 if (ret || io_should_wake(iowq))
6977 return ret;
6978 /* let the caller flush overflows, retry */
6979 if (test_bit(0, &ctx->cq_check_overflow))
6980 return 1;
6981
6982 *timeout = schedule_timeout(*timeout);
6983 return !*timeout ? -ETIME : 1;
6984}
6985
2b188cc1
JA
6986/*
6987 * Wait until events become available, if we don't already have some. The
6988 * application must reap them itself, as they reside on the shared cq ring.
6989 */
6990static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
c73ebb68
HX
6991 const sigset_t __user *sig, size_t sigsz,
6992 struct __kernel_timespec __user *uts)
2b188cc1 6993{
bda52162
JA
6994 struct io_wait_queue iowq = {
6995 .wq = {
6996 .private = current,
6997 .func = io_wake_function,
6998 .entry = LIST_HEAD_INIT(iowq.wq.entry),
6999 },
7000 .ctx = ctx,
7001 .to_wait = min_events,
7002 };
75b28aff 7003 struct io_rings *rings = ctx->rings;
c1d5a224
PB
7004 signed long timeout = MAX_SCHEDULE_TIMEOUT;
7005 int ret;
2b188cc1 7006
b41e9852 7007 do {
6c2450ae 7008 io_cqring_overflow_flush(ctx, false);
6c503150 7009 if (io_cqring_events(ctx) >= min_events)
b41e9852 7010 return 0;
4c6e277c 7011 if (!io_run_task_work())
b41e9852 7012 break;
b41e9852 7013 } while (1);
2b188cc1
JA
7014
7015 if (sig) {
9e75ad5d
AB
7016#ifdef CONFIG_COMPAT
7017 if (in_compat_syscall())
7018 ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
b772434b 7019 sigsz);
9e75ad5d
AB
7020 else
7021#endif
b772434b 7022 ret = set_user_sigmask(sig, sigsz);
9e75ad5d 7023
2b188cc1
JA
7024 if (ret)
7025 return ret;
7026 }
7027
c73ebb68 7028 if (uts) {
c1d5a224
PB
7029 struct timespec64 ts;
7030
c73ebb68
HX
7031 if (get_timespec64(&ts, uts))
7032 return -EFAULT;
7033 timeout = timespec64_to_jiffies(&ts);
7034 }
7035
bda52162 7036 iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
c826bd7a 7037 trace_io_uring_cqring_wait(ctx, min_events);
bda52162 7038 do {
ca0a2651 7039 /* if we can't even flush overflow, don't wait for more */
6c2450ae 7040 if (!io_cqring_overflow_flush(ctx, false)) {
ca0a2651
JA
7041 ret = -EBUSY;
7042 break;
7043 }
bda52162
JA
7044 prepare_to_wait_exclusive(&ctx->wait, &iowq.wq,
7045 TASK_INTERRUPTIBLE);
eeb60b9a
PB
7046 ret = io_cqring_wait_schedule(ctx, &iowq, &timeout);
7047 finish_wait(&ctx->wait, &iowq.wq);
ca0a2651 7048 cond_resched();
eeb60b9a 7049 } while (ret > 0);
bda52162 7050
b7db41c9 7051 restore_saved_sigmask_unless(ret == -EINTR);
2b188cc1 7052
75b28aff 7053 return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
2b188cc1
JA
7054}
7055
6b06314c
JA
7056static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
7057{
7058#if defined(CONFIG_UNIX)
7059 if (ctx->ring_sock) {
7060 struct sock *sock = ctx->ring_sock->sk;
7061 struct sk_buff *skb;
7062
7063 while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
7064 kfree_skb(skb);
7065 }
7066#else
7067 int i;
7068
65e19f54
JA
7069 for (i = 0; i < ctx->nr_user_files; i++) {
7070 struct file *file;
7071
7072 file = io_file_from_index(ctx, i);
7073 if (file)
7074 fput(file);
7075 }
6b06314c
JA
7076#endif
7077}
7078
00835dce 7079static void io_rsrc_data_ref_zero(struct percpu_ref *ref)
05f3fb3c 7080{
269bbe5f 7081 struct fixed_rsrc_data *data;
05f3fb3c 7082
269bbe5f 7083 data = container_of(ref, struct fixed_rsrc_data, refs);
05f3fb3c
JA
7084 complete(&data->done);
7085}
7086
2a63b2d9 7087static inline void io_rsrc_ref_lock(struct io_ring_ctx *ctx)
1642b445 7088{
2a63b2d9 7089 spin_lock_bh(&ctx->rsrc_ref_lock);
1642b445
PB
7090}
7091
2a63b2d9 7092static inline void io_rsrc_ref_unlock(struct io_ring_ctx *ctx)
6b06314c 7093{
2a63b2d9
BM
7094 spin_unlock_bh(&ctx->rsrc_ref_lock);
7095}
65e19f54 7096
d67d2263
BM
7097static void io_sqe_rsrc_set_node(struct io_ring_ctx *ctx,
7098 struct fixed_rsrc_data *rsrc_data,
269bbe5f 7099 struct fixed_rsrc_ref_node *ref_node)
1642b445 7100{
2a63b2d9 7101 io_rsrc_ref_lock(ctx);
269bbe5f 7102 rsrc_data->node = ref_node;
d67d2263 7103 list_add_tail(&ref_node->node, &ctx->rsrc_ref_list);
2a63b2d9 7104 io_rsrc_ref_unlock(ctx);
269bbe5f 7105 percpu_ref_get(&rsrc_data->refs);
1642b445
PB
7106}
7107
8bad28d8 7108static void io_sqe_rsrc_kill_node(struct io_ring_ctx *ctx, struct fixed_rsrc_data *data)
6b06314c 7109{
8bad28d8 7110 struct fixed_rsrc_ref_node *ref_node = NULL;
6b06314c 7111
2a63b2d9 7112 io_rsrc_ref_lock(ctx);
1e5d770b 7113 ref_node = data->node;
e6cb007c 7114 data->node = NULL;
2a63b2d9 7115 io_rsrc_ref_unlock(ctx);
05589553
XW
7116 if (ref_node)
7117 percpu_ref_kill(&ref_node->refs);
8bad28d8
HX
7118}
7119
8dd03afe
PB
7120static int io_rsrc_refnode_prealloc(struct io_ring_ctx *ctx)
7121{
7122 if (ctx->rsrc_backup_node)
7123 return 0;
7124 ctx->rsrc_backup_node = alloc_fixed_rsrc_ref_node(ctx);
7125 return ctx->rsrc_backup_node ? 0 : -ENOMEM;
7126}
7127
7128static struct fixed_rsrc_ref_node *
7129io_rsrc_refnode_get(struct io_ring_ctx *ctx,
7130 struct fixed_rsrc_data *rsrc_data,
7131 void (*rsrc_put)(struct io_ring_ctx *ctx,
7132 struct io_rsrc_put *prsrc))
7133{
7134 struct fixed_rsrc_ref_node *node = ctx->rsrc_backup_node;
7135
7136 WARN_ON_ONCE(!node);
7137
7138 ctx->rsrc_backup_node = NULL;
7139 node->rsrc_data = rsrc_data;
7140 node->rsrc_put = rsrc_put;
7141 return node;
7142}
7143
8bad28d8
HX
7144static int io_rsrc_ref_quiesce(struct fixed_rsrc_data *data,
7145 struct io_ring_ctx *ctx,
f2303b1f
PB
7146 void (*rsrc_put)(struct io_ring_ctx *ctx,
7147 struct io_rsrc_put *prsrc))
8bad28d8 7148{
8dd03afe 7149 struct fixed_rsrc_ref_node *node;
8bad28d8 7150 int ret;
05589553 7151
8bad28d8
HX
7152 if (data->quiesce)
7153 return -ENXIO;
05589553 7154
8bad28d8 7155 data->quiesce = true;
1ffc5422 7156 do {
8dd03afe
PB
7157 ret = io_rsrc_refnode_prealloc(ctx);
7158 if (ret)
f2303b1f 7159 break;
8bad28d8
HX
7160 io_sqe_rsrc_kill_node(ctx, data);
7161 percpu_ref_kill(&data->refs);
7162 flush_delayed_work(&ctx->rsrc_put_work);
7163
1ffc5422
PB
7164 ret = wait_for_completion_interruptible(&data->done);
7165 if (!ret)
7166 break;
8bad28d8 7167
cb5e1b81 7168 percpu_ref_resurrect(&data->refs);
8dd03afe
PB
7169 node = io_rsrc_refnode_get(ctx, data, rsrc_put);
7170 io_sqe_rsrc_set_node(ctx, data, node);
cb5e1b81 7171 reinit_completion(&data->done);
8dd03afe 7172
8bad28d8 7173 mutex_unlock(&ctx->uring_lock);
1ffc5422 7174 ret = io_run_task_work_sig();
8bad28d8 7175 mutex_lock(&ctx->uring_lock);
f2303b1f 7176 } while (ret >= 0);
8bad28d8 7177 data->quiesce = false;
05f3fb3c 7178
8bad28d8 7179 return ret;
d7954b2b
BM
7180}
7181
1ad555c6
BM
7182static struct fixed_rsrc_data *alloc_fixed_rsrc_data(struct io_ring_ctx *ctx)
7183{
7184 struct fixed_rsrc_data *data;
7185
7186 data = kzalloc(sizeof(*data), GFP_KERNEL);
7187 if (!data)
7188 return NULL;
7189
00835dce 7190 if (percpu_ref_init(&data->refs, io_rsrc_data_ref_zero,
1ad555c6
BM
7191 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) {
7192 kfree(data);
7193 return NULL;
7194 }
7195 data->ctx = ctx;
7196 init_completion(&data->done);
7197 return data;
7198}
7199
7200static void free_fixed_rsrc_data(struct fixed_rsrc_data *data)
7201{
7202 percpu_ref_exit(&data->refs);
7203 kfree(data->table);
7204 kfree(data);
7205}
7206
d7954b2b
BM
7207static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
7208{
7209 struct fixed_rsrc_data *data = ctx->file_data;
d7954b2b
BM
7210 unsigned nr_tables, i;
7211 int ret;
7212
8bad28d8
HX
7213 /*
7214 * percpu_ref_is_dying() is to stop parallel files unregister
7215 * Since we possibly drop uring lock later in this function to
7216 * run task work.
7217 */
7218 if (!data || percpu_ref_is_dying(&data->refs))
d7954b2b 7219 return -ENXIO;
f2303b1f 7220 ret = io_rsrc_ref_quiesce(data, ctx, io_ring_file_put);
d7954b2b
BM
7221 if (ret)
7222 return ret;
7223
6b06314c 7224 __io_sqe_files_unregister(ctx);
65e19f54
JA
7225 nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE);
7226 for (i = 0; i < nr_tables; i++)
05f3fb3c 7227 kfree(data->table[i].files);
1ad555c6 7228 free_fixed_rsrc_data(data);
05f3fb3c 7229 ctx->file_data = NULL;
6b06314c
JA
7230 ctx->nr_user_files = 0;
7231 return 0;
7232}
7233
37d1e2e3 7234static void io_sq_thread_unpark(struct io_sq_data *sqd)
09a6f4ef 7235 __releases(&sqd->lock)
37d1e2e3 7236{
521d6a73
PB
7237 WARN_ON_ONCE(sqd->thread == current);
7238
9e138a48
PB
7239 /*
7240 * Do the dance but not conditional clear_bit() because it'd race with
7241 * other threads incrementing park_pending and setting the bit.
7242 */
37d1e2e3 7243 clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
9e138a48
PB
7244 if (atomic_dec_return(&sqd->park_pending))
7245 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
09a6f4ef 7246 mutex_unlock(&sqd->lock);
37d1e2e3
JA
7247}
7248
86e0d676 7249static void io_sq_thread_park(struct io_sq_data *sqd)
09a6f4ef 7250 __acquires(&sqd->lock)
37d1e2e3 7251{
521d6a73
PB
7252 WARN_ON_ONCE(sqd->thread == current);
7253
9e138a48 7254 atomic_inc(&sqd->park_pending);
86e0d676 7255 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
09a6f4ef 7256 mutex_lock(&sqd->lock);
05962f95 7257 if (sqd->thread)
86e0d676 7258 wake_up_process(sqd->thread);
37d1e2e3
JA
7259}
7260
7261static void io_sq_thread_stop(struct io_sq_data *sqd)
7262{
521d6a73
PB
7263 WARN_ON_ONCE(sqd->thread == current);
7264
09a6f4ef 7265 mutex_lock(&sqd->lock);
05962f95 7266 set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
e8f98f24
JA
7267 if (sqd->thread)
7268 wake_up_process(sqd->thread);
09a6f4ef 7269 mutex_unlock(&sqd->lock);
05962f95 7270 wait_for_completion(&sqd->exited);
37d1e2e3
JA
7271}
7272
534ca6d6 7273static void io_put_sq_data(struct io_sq_data *sqd)
6c271ce2 7274{
534ca6d6 7275 if (refcount_dec_and_test(&sqd->refs)) {
9e138a48
PB
7276 WARN_ON_ONCE(atomic_read(&sqd->park_pending));
7277
37d1e2e3
JA
7278 io_sq_thread_stop(sqd);
7279 kfree(sqd);
7280 }
7281}
7282
7283static void io_sq_thread_finish(struct io_ring_ctx *ctx)
7284{
7285 struct io_sq_data *sqd = ctx->sq_data;
7286
7287 if (sqd) {
05962f95 7288 io_sq_thread_park(sqd);
521d6a73 7289 list_del_init(&ctx->sqd_list);
37d1e2e3 7290 io_sqd_update_thread_idle(sqd);
05962f95 7291 io_sq_thread_unpark(sqd);
37d1e2e3
JA
7292
7293 io_put_sq_data(sqd);
7294 ctx->sq_data = NULL;
7c30f36a
SM
7295 if (ctx->sq_creds)
7296 put_cred(ctx->sq_creds);
534ca6d6
JA
7297 }
7298}
7299
aa06165d
JA
7300static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
7301{
7302 struct io_ring_ctx *ctx_attach;
7303 struct io_sq_data *sqd;
7304 struct fd f;
7305
7306 f = fdget(p->wq_fd);
7307 if (!f.file)
7308 return ERR_PTR(-ENXIO);
7309 if (f.file->f_op != &io_uring_fops) {
7310 fdput(f);
7311 return ERR_PTR(-EINVAL);
7312 }
7313
7314 ctx_attach = f.file->private_data;
7315 sqd = ctx_attach->sq_data;
7316 if (!sqd) {
7317 fdput(f);
7318 return ERR_PTR(-EINVAL);
7319 }
5c2469e0
JA
7320 if (sqd->task_tgid != current->tgid) {
7321 fdput(f);
7322 return ERR_PTR(-EPERM);
7323 }
aa06165d
JA
7324
7325 refcount_inc(&sqd->refs);
7326 fdput(f);
7327 return sqd;
7328}
7329
26984fbf
PB
7330static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
7331 bool *attached)
534ca6d6
JA
7332{
7333 struct io_sq_data *sqd;
7334
26984fbf 7335 *attached = false;
5c2469e0
JA
7336 if (p->flags & IORING_SETUP_ATTACH_WQ) {
7337 sqd = io_attach_sq_data(p);
26984fbf
PB
7338 if (!IS_ERR(sqd)) {
7339 *attached = true;
5c2469e0 7340 return sqd;
26984fbf 7341 }
5c2469e0
JA
7342 /* fall through for EPERM case, setup new sqd/task */
7343 if (PTR_ERR(sqd) != -EPERM)
7344 return sqd;
7345 }
aa06165d 7346
534ca6d6
JA
7347 sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
7348 if (!sqd)
7349 return ERR_PTR(-ENOMEM);
7350
9e138a48 7351 atomic_set(&sqd->park_pending, 0);
534ca6d6 7352 refcount_set(&sqd->refs, 1);
69fb2131 7353 INIT_LIST_HEAD(&sqd->ctx_list);
09a6f4ef 7354 mutex_init(&sqd->lock);
534ca6d6 7355 init_waitqueue_head(&sqd->wait);
37d1e2e3 7356 init_completion(&sqd->exited);
534ca6d6
JA
7357 return sqd;
7358}
7359
6b06314c 7360#if defined(CONFIG_UNIX)
6b06314c
JA
7361/*
7362 * Ensure the UNIX gc is aware of our file set, so we are certain that
7363 * the io_uring can be safely unregistered on process exit, even if we have
7364 * loops in the file referencing.
7365 */
7366static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
7367{
7368 struct sock *sk = ctx->ring_sock->sk;
7369 struct scm_fp_list *fpl;
7370 struct sk_buff *skb;
08a45173 7371 int i, nr_files;
6b06314c 7372
6b06314c
JA
7373 fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
7374 if (!fpl)
7375 return -ENOMEM;
7376
7377 skb = alloc_skb(0, GFP_KERNEL);
7378 if (!skb) {
7379 kfree(fpl);
7380 return -ENOMEM;
7381 }
7382
7383 skb->sk = sk;
6b06314c 7384
08a45173 7385 nr_files = 0;
62e398be 7386 fpl->user = get_uid(current_user());
6b06314c 7387 for (i = 0; i < nr; i++) {
65e19f54
JA
7388 struct file *file = io_file_from_index(ctx, i + offset);
7389
7390 if (!file)
08a45173 7391 continue;
65e19f54 7392 fpl->fp[nr_files] = get_file(file);
08a45173
JA
7393 unix_inflight(fpl->user, fpl->fp[nr_files]);
7394 nr_files++;
6b06314c
JA
7395 }
7396
08a45173
JA
7397 if (nr_files) {
7398 fpl->max = SCM_MAX_FD;
7399 fpl->count = nr_files;
7400 UNIXCB(skb).fp = fpl;
05f3fb3c 7401 skb->destructor = unix_destruct_scm;
08a45173
JA
7402 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
7403 skb_queue_head(&sk->sk_receive_queue, skb);
6b06314c 7404
08a45173
JA
7405 for (i = 0; i < nr_files; i++)
7406 fput(fpl->fp[i]);
7407 } else {
7408 kfree_skb(skb);
7409 kfree(fpl);
7410 }
6b06314c
JA
7411
7412 return 0;
7413}
7414
7415/*
7416 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7417 * causes regular reference counting to break down. We rely on the UNIX
7418 * garbage collection to take care of this problem for us.
7419 */
7420static int io_sqe_files_scm(struct io_ring_ctx *ctx)
7421{
7422 unsigned left, total;
7423 int ret = 0;
7424
7425 total = 0;
7426 left = ctx->nr_user_files;
7427 while (left) {
7428 unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
6b06314c
JA
7429
7430 ret = __io_sqe_files_scm(ctx, this_files, total);
7431 if (ret)
7432 break;
7433 left -= this_files;
7434 total += this_files;
7435 }
7436
7437 if (!ret)
7438 return 0;
7439
7440 while (total < ctx->nr_user_files) {
65e19f54
JA
7441 struct file *file = io_file_from_index(ctx, total);
7442
7443 if (file)
7444 fput(file);
6b06314c
JA
7445 total++;
7446 }
7447
7448 return ret;
7449}
7450#else
7451static int io_sqe_files_scm(struct io_ring_ctx *ctx)
7452{
7453 return 0;
7454}
7455#endif
7456
269bbe5f 7457static int io_sqe_alloc_file_tables(struct fixed_rsrc_data *file_data,
5398ae69 7458 unsigned nr_tables, unsigned nr_files)
65e19f54
JA
7459{
7460 int i;
7461
7462 for (i = 0; i < nr_tables; i++) {
269bbe5f 7463 struct fixed_rsrc_table *table = &file_data->table[i];
65e19f54
JA
7464 unsigned this_files;
7465
7466 this_files = min(nr_files, IORING_MAX_FILES_TABLE);
7467 table->files = kcalloc(this_files, sizeof(struct file *),
7468 GFP_KERNEL);
7469 if (!table->files)
7470 break;
7471 nr_files -= this_files;
7472 }
7473
7474 if (i == nr_tables)
7475 return 0;
7476
7477 for (i = 0; i < nr_tables; i++) {
269bbe5f 7478 struct fixed_rsrc_table *table = &file_data->table[i];
65e19f54
JA
7479 kfree(table->files);
7480 }
7481 return 1;
7482}
7483
50238531 7484static void io_ring_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
05f3fb3c 7485{
50238531 7486 struct file *file = prsrc->file;
05f3fb3c
JA
7487#if defined(CONFIG_UNIX)
7488 struct sock *sock = ctx->ring_sock->sk;
7489 struct sk_buff_head list, *head = &sock->sk_receive_queue;
7490 struct sk_buff *skb;
7491 int i;
7492
7493 __skb_queue_head_init(&list);
7494
7495 /*
7496 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7497 * remove this entry and rearrange the file array.
7498 */
7499 skb = skb_dequeue(head);
7500 while (skb) {
7501 struct scm_fp_list *fp;
7502
7503 fp = UNIXCB(skb).fp;
7504 for (i = 0; i < fp->count; i++) {
7505 int left;
7506
7507 if (fp->fp[i] != file)
7508 continue;
7509
7510 unix_notinflight(fp->user, fp->fp[i]);
7511 left = fp->count - 1 - i;
7512 if (left) {
7513 memmove(&fp->fp[i], &fp->fp[i + 1],
7514 left * sizeof(struct file *));
7515 }
7516 fp->count--;
7517 if (!fp->count) {
7518 kfree_skb(skb);
7519 skb = NULL;
7520 } else {
7521 __skb_queue_tail(&list, skb);
7522 }
7523 fput(file);
7524 file = NULL;
7525 break;
7526 }
7527
7528 if (!file)
7529 break;
7530
7531 __skb_queue_tail(&list, skb);
7532
7533 skb = skb_dequeue(head);
7534 }
7535
7536 if (skb_peek(&list)) {
7537 spin_lock_irq(&head->lock);
7538 while ((skb = __skb_dequeue(&list)) != NULL)
7539 __skb_queue_tail(head, skb);
7540 spin_unlock_irq(&head->lock);
7541 }
7542#else
7543 fput(file);
7544#endif
7545}
7546
269bbe5f 7547static void __io_rsrc_put_work(struct fixed_rsrc_ref_node *ref_node)
65e19f54 7548{
269bbe5f
BM
7549 struct fixed_rsrc_data *rsrc_data = ref_node->rsrc_data;
7550 struct io_ring_ctx *ctx = rsrc_data->ctx;
7551 struct io_rsrc_put *prsrc, *tmp;
05589553 7552
269bbe5f
BM
7553 list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
7554 list_del(&prsrc->list);
50238531 7555 ref_node->rsrc_put(ctx, prsrc);
269bbe5f 7556 kfree(prsrc);
65e19f54 7557 }
05589553 7558
05589553
XW
7559 percpu_ref_exit(&ref_node->refs);
7560 kfree(ref_node);
269bbe5f 7561 percpu_ref_put(&rsrc_data->refs);
2faf852d 7562}
65e19f54 7563
269bbe5f 7564static void io_rsrc_put_work(struct work_struct *work)
4a38aed2
JA
7565{
7566 struct io_ring_ctx *ctx;
7567 struct llist_node *node;
7568
269bbe5f
BM
7569 ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
7570 node = llist_del_all(&ctx->rsrc_put_llist);
4a38aed2
JA
7571
7572 while (node) {
269bbe5f 7573 struct fixed_rsrc_ref_node *ref_node;
4a38aed2
JA
7574 struct llist_node *next = node->next;
7575
269bbe5f
BM
7576 ref_node = llist_entry(node, struct fixed_rsrc_ref_node, llist);
7577 __io_rsrc_put_work(ref_node);
4a38aed2
JA
7578 node = next;
7579 }
7580}
7581
00835dce 7582static void io_rsrc_node_ref_zero(struct percpu_ref *ref)
2faf852d 7583{
269bbe5f
BM
7584 struct fixed_rsrc_ref_node *ref_node;
7585 struct fixed_rsrc_data *data;
4a38aed2 7586 struct io_ring_ctx *ctx;
e297822b 7587 bool first_add = false;
4a38aed2 7588 int delay = HZ;
65e19f54 7589
269bbe5f
BM
7590 ref_node = container_of(ref, struct fixed_rsrc_ref_node, refs);
7591 data = ref_node->rsrc_data;
e297822b
PB
7592 ctx = data->ctx;
7593
2a63b2d9 7594 io_rsrc_ref_lock(ctx);
e297822b
PB
7595 ref_node->done = true;
7596
d67d2263
BM
7597 while (!list_empty(&ctx->rsrc_ref_list)) {
7598 ref_node = list_first_entry(&ctx->rsrc_ref_list,
269bbe5f 7599 struct fixed_rsrc_ref_node, node);
e297822b
PB
7600 /* recycle ref nodes in order */
7601 if (!ref_node->done)
7602 break;
7603 list_del(&ref_node->node);
269bbe5f 7604 first_add |= llist_add(&ref_node->llist, &ctx->rsrc_put_llist);
e297822b 7605 }
2a63b2d9 7606 io_rsrc_ref_unlock(ctx);
05589553 7607
e297822b 7608 if (percpu_ref_is_dying(&data->refs))
4a38aed2 7609 delay = 0;
05589553 7610
4a38aed2 7611 if (!delay)
269bbe5f 7612 mod_delayed_work(system_wq, &ctx->rsrc_put_work, 0);
4a38aed2 7613 else if (first_add)
269bbe5f 7614 queue_delayed_work(system_wq, &ctx->rsrc_put_work, delay);
05f3fb3c 7615}
65e19f54 7616
6802535d 7617static struct fixed_rsrc_ref_node *alloc_fixed_rsrc_ref_node(
05589553 7618 struct io_ring_ctx *ctx)
05f3fb3c 7619{
269bbe5f 7620 struct fixed_rsrc_ref_node *ref_node;
05f3fb3c 7621
05589553
XW
7622 ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
7623 if (!ref_node)
3e2224c5 7624 return NULL;
05f3fb3c 7625
00835dce 7626 if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
05589553
XW
7627 0, GFP_KERNEL)) {
7628 kfree(ref_node);
3e2224c5 7629 return NULL;
05589553
XW
7630 }
7631 INIT_LIST_HEAD(&ref_node->node);
269bbe5f 7632 INIT_LIST_HEAD(&ref_node->rsrc_list);
e297822b 7633 ref_node->done = false;
05589553 7634 return ref_node;
05589553
XW
7635}
7636
bc9744cd
PB
7637static void init_fixed_file_ref_node(struct io_ring_ctx *ctx,
7638 struct fixed_rsrc_ref_node *ref_node)
6802535d 7639{
269bbe5f 7640 ref_node->rsrc_data = ctx->file_data;
50238531 7641 ref_node->rsrc_put = io_ring_file_put;
05589553
XW
7642}
7643
269bbe5f 7644static void destroy_fixed_rsrc_ref_node(struct fixed_rsrc_ref_node *ref_node)
05589553
XW
7645{
7646 percpu_ref_exit(&ref_node->refs);
7647 kfree(ref_node);
65e19f54
JA
7648}
7649
ea64ec02 7650
6b06314c
JA
7651static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
7652 unsigned nr_args)
7653{
7654 __s32 __user *fds = (__s32 __user *) arg;
600cf3f8 7655 unsigned nr_tables, i;
05f3fb3c 7656 struct file *file;
600cf3f8 7657 int fd, ret = -ENOMEM;
269bbe5f
BM
7658 struct fixed_rsrc_ref_node *ref_node;
7659 struct fixed_rsrc_data *file_data;
6b06314c 7660
05f3fb3c 7661 if (ctx->file_data)
6b06314c
JA
7662 return -EBUSY;
7663 if (!nr_args)
7664 return -EINVAL;
7665 if (nr_args > IORING_MAX_FIXED_FILES)
7666 return -EMFILE;
7667
1ad555c6 7668 file_data = alloc_fixed_rsrc_data(ctx);
5398ae69 7669 if (!file_data)
05f3fb3c 7670 return -ENOMEM;
13770a71 7671 ctx->file_data = file_data;
05f3fb3c 7672
65e19f54 7673 nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE);
035fbafc 7674 file_data->table = kcalloc(nr_tables, sizeof(*file_data->table),
5398ae69 7675 GFP_KERNEL);
600cf3f8
PB
7676 if (!file_data->table)
7677 goto out_free;
05f3fb3c 7678
600cf3f8 7679 if (io_sqe_alloc_file_tables(file_data, nr_tables, nr_args))
1ad555c6 7680 goto out_free;
65e19f54 7681
08a45173 7682 for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
7b29f92d
JA
7683 unsigned long file_ptr;
7684
600cf3f8
PB
7685 if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
7686 ret = -EFAULT;
7687 goto out_fput;
7688 }
08a45173 7689 /* allow sparse sets */
600cf3f8 7690 if (fd == -1)
08a45173 7691 continue;
6b06314c 7692
05f3fb3c 7693 file = fget(fd);
6b06314c 7694 ret = -EBADF;
05f3fb3c 7695 if (!file)
600cf3f8 7696 goto out_fput;
05f3fb3c 7697
6b06314c
JA
7698 /*
7699 * Don't allow io_uring instances to be registered. If UNIX
7700 * isn't enabled, then this causes a reference cycle and this
7701 * instance can never get freed. If UNIX is enabled we'll
7702 * handle it just fine, but there's still no point in allowing
7703 * a ring fd as it doesn't support regular read/write anyway.
7704 */
05f3fb3c
JA
7705 if (file->f_op == &io_uring_fops) {
7706 fput(file);
600cf3f8 7707 goto out_fput;
6b06314c 7708 }
7b29f92d
JA
7709 file_ptr = (unsigned long) file;
7710 if (__io_file_supports_async(file, READ))
7711 file_ptr |= FFS_ASYNC_READ;
7712 if (__io_file_supports_async(file, WRITE))
7713 file_ptr |= FFS_ASYNC_WRITE;
7714 if (S_ISREG(file_inode(file)->i_mode))
7715 file_ptr |= FFS_ISREG;
7716 *io_fixed_file_slot(file_data, i) = (struct file *) file_ptr;
6b06314c
JA
7717 }
7718
6b06314c 7719 ret = io_sqe_files_scm(ctx);
05589553 7720 if (ret) {
6b06314c 7721 io_sqe_files_unregister(ctx);
05589553
XW
7722 return ret;
7723 }
6b06314c 7724
bc9744cd 7725 ref_node = alloc_fixed_rsrc_ref_node(ctx);
3e2224c5 7726 if (!ref_node) {
05589553 7727 io_sqe_files_unregister(ctx);
3e2224c5 7728 return -ENOMEM;
05589553 7729 }
bc9744cd 7730 init_fixed_file_ref_node(ctx, ref_node);
05589553 7731
d67d2263 7732 io_sqe_rsrc_set_node(ctx, file_data, ref_node);
6b06314c 7733 return ret;
600cf3f8
PB
7734out_fput:
7735 for (i = 0; i < ctx->nr_user_files; i++) {
7736 file = io_file_from_index(ctx, i);
7737 if (file)
7738 fput(file);
7739 }
7740 for (i = 0; i < nr_tables; i++)
7741 kfree(file_data->table[i].files);
7742 ctx->nr_user_files = 0;
600cf3f8 7743out_free:
1ad555c6 7744 free_fixed_rsrc_data(ctx->file_data);
55cbc256 7745 ctx->file_data = NULL;
6b06314c
JA
7746 return ret;
7747}
7748
c3a31e60
JA
7749static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
7750 int index)
7751{
7752#if defined(CONFIG_UNIX)
7753 struct sock *sock = ctx->ring_sock->sk;
7754 struct sk_buff_head *head = &sock->sk_receive_queue;
7755 struct sk_buff *skb;
7756
7757 /*
7758 * See if we can merge this file into an existing skb SCM_RIGHTS
7759 * file set. If there's no room, fall back to allocating a new skb
7760 * and filling it in.
7761 */
7762 spin_lock_irq(&head->lock);
7763 skb = skb_peek(head);
7764 if (skb) {
7765 struct scm_fp_list *fpl = UNIXCB(skb).fp;
7766
7767 if (fpl->count < SCM_MAX_FD) {
7768 __skb_unlink(skb, head);
7769 spin_unlock_irq(&head->lock);
7770 fpl->fp[fpl->count] = get_file(file);
7771 unix_inflight(fpl->user, fpl->fp[fpl->count]);
7772 fpl->count++;
7773 spin_lock_irq(&head->lock);
7774 __skb_queue_head(head, skb);
7775 } else {
7776 skb = NULL;
7777 }
7778 }
7779 spin_unlock_irq(&head->lock);
7780
7781 if (skb) {
7782 fput(file);
7783 return 0;
7784 }
7785
7786 return __io_sqe_files_scm(ctx, 1, index);
7787#else
7788 return 0;
7789#endif
7790}
7791
50238531 7792static int io_queue_rsrc_removal(struct fixed_rsrc_data *data, void *rsrc)
05f3fb3c 7793{
269bbe5f
BM
7794 struct io_rsrc_put *prsrc;
7795 struct fixed_rsrc_ref_node *ref_node = data->node;
05f3fb3c 7796
269bbe5f
BM
7797 prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
7798 if (!prsrc)
a5318d3c 7799 return -ENOMEM;
05f3fb3c 7800
50238531 7801 prsrc->rsrc = rsrc;
269bbe5f 7802 list_add(&prsrc->list, &ref_node->rsrc_list);
05589553 7803
a5318d3c 7804 return 0;
05f3fb3c
JA
7805}
7806
269bbe5f
BM
7807static inline int io_queue_file_removal(struct fixed_rsrc_data *data,
7808 struct file *file)
7809{
50238531 7810 return io_queue_rsrc_removal(data, (void *)file);
269bbe5f
BM
7811}
7812
05f3fb3c 7813static int __io_sqe_files_update(struct io_ring_ctx *ctx,
269bbe5f 7814 struct io_uring_rsrc_update *up,
05f3fb3c
JA
7815 unsigned nr_args)
7816{
269bbe5f
BM
7817 struct fixed_rsrc_data *data = ctx->file_data;
7818 struct fixed_rsrc_ref_node *ref_node;
ea64ec02 7819 struct file *file, **file_slot;
c3a31e60
JA
7820 __s32 __user *fds;
7821 int fd, i, err;
7822 __u32 done;
05589553 7823 bool needs_switch = false;
c3a31e60 7824
05f3fb3c 7825 if (check_add_overflow(up->offset, nr_args, &done))
c3a31e60
JA
7826 return -EOVERFLOW;
7827 if (done > ctx->nr_user_files)
7828 return -EINVAL;
8dd03afe
PB
7829 err = io_rsrc_refnode_prealloc(ctx);
7830 if (err)
7831 return err;
05589553 7832
269bbe5f 7833 fds = u64_to_user_ptr(up->data);
67973b93 7834 for (done = 0; done < nr_args; done++) {
c3a31e60
JA
7835 err = 0;
7836 if (copy_from_user(&fd, &fds[done], sizeof(fd))) {
7837 err = -EFAULT;
7838 break;
7839 }
4e0377a1 7840 if (fd == IORING_REGISTER_FILES_SKIP)
7841 continue;
7842
67973b93 7843 i = array_index_nospec(up->offset + done, ctx->nr_user_files);
ea64ec02
PB
7844 file_slot = io_fixed_file_slot(ctx->file_data, i);
7845
7846 if (*file_slot) {
7b29f92d
JA
7847 file = (struct file *) ((unsigned long) *file_slot & FFS_MASK);
7848 err = io_queue_file_removal(data, file);
a5318d3c
HD
7849 if (err)
7850 break;
ea64ec02 7851 *file_slot = NULL;
05589553 7852 needs_switch = true;
c3a31e60
JA
7853 }
7854 if (fd != -1) {
c3a31e60
JA
7855 file = fget(fd);
7856 if (!file) {
7857 err = -EBADF;
7858 break;
7859 }
7860 /*
7861 * Don't allow io_uring instances to be registered. If
7862 * UNIX isn't enabled, then this causes a reference
7863 * cycle and this instance can never get freed. If UNIX
7864 * is enabled we'll handle it just fine, but there's
7865 * still no point in allowing a ring fd as it doesn't
7866 * support regular read/write anyway.
7867 */
7868 if (file->f_op == &io_uring_fops) {
7869 fput(file);
7870 err = -EBADF;
7871 break;
7872 }
e68a3ff8 7873 *file_slot = file;
c3a31e60 7874 err = io_sqe_file_register(ctx, file, i);
f3bd9dae 7875 if (err) {
e68a3ff8 7876 *file_slot = NULL;
f3bd9dae 7877 fput(file);
c3a31e60 7878 break;
f3bd9dae 7879 }
c3a31e60 7880 }
05f3fb3c
JA
7881 }
7882
05589553 7883 if (needs_switch) {
b2e96852 7884 percpu_ref_kill(&data->node->refs);
8dd03afe 7885 ref_node = io_rsrc_refnode_get(ctx, data, io_ring_file_put);
d67d2263 7886 io_sqe_rsrc_set_node(ctx, data, ref_node);
8dd03afe 7887 }
c3a31e60
JA
7888 return done ? done : err;
7889}
05589553 7890
05f3fb3c
JA
7891static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg,
7892 unsigned nr_args)
7893{
269bbe5f 7894 struct io_uring_rsrc_update up;
05f3fb3c
JA
7895
7896 if (!ctx->file_data)
7897 return -ENXIO;
7898 if (!nr_args)
7899 return -EINVAL;
7900 if (copy_from_user(&up, arg, sizeof(up)))
7901 return -EFAULT;
7902 if (up.resv)
7903 return -EINVAL;
7904
7905 return __io_sqe_files_update(ctx, &up, nr_args);
7906}
c3a31e60 7907
5280f7e5 7908static struct io_wq_work *io_free_work(struct io_wq_work *work)
7d723065
JA
7909{
7910 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
7911
5280f7e5
PB
7912 req = io_put_req_find_next(req);
7913 return req ? &req->work : NULL;
7d723065
JA
7914}
7915
685fe7fe
JA
7916static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
7917 struct task_struct *task)
24369c2e 7918{
e941894e 7919 struct io_wq_hash *hash;
24369c2e 7920 struct io_wq_data data;
24369c2e 7921 unsigned int concurrency;
24369c2e 7922
e941894e
JA
7923 hash = ctx->hash_map;
7924 if (!hash) {
7925 hash = kzalloc(sizeof(*hash), GFP_KERNEL);
7926 if (!hash)
7927 return ERR_PTR(-ENOMEM);
7928 refcount_set(&hash->refs, 1);
7929 init_waitqueue_head(&hash->wait);
7930 ctx->hash_map = hash;
24369c2e
PB
7931 }
7932
e941894e 7933 data.hash = hash;
685fe7fe 7934 data.task = task;
e9fd9396 7935 data.free_work = io_free_work;
f5fa38c5 7936 data.do_work = io_wq_submit_work;
24369c2e 7937
d25e3a3d
JA
7938 /* Do QD, or 4 * CPUS, whatever is smallest */
7939 concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
24369c2e 7940
5aa75ed5 7941 return io_wq_create(concurrency, &data);
24369c2e
PB
7942}
7943
5aa75ed5
JA
7944static int io_uring_alloc_task_context(struct task_struct *task,
7945 struct io_ring_ctx *ctx)
0f212204
JA
7946{
7947 struct io_uring_task *tctx;
d8a6df10 7948 int ret;
0f212204
JA
7949
7950 tctx = kmalloc(sizeof(*tctx), GFP_KERNEL);
7951 if (unlikely(!tctx))
7952 return -ENOMEM;
7953
d8a6df10
JA
7954 ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
7955 if (unlikely(ret)) {
7956 kfree(tctx);
7957 return ret;
7958 }
7959
685fe7fe 7960 tctx->io_wq = io_init_wq_offload(ctx, task);
5aa75ed5
JA
7961 if (IS_ERR(tctx->io_wq)) {
7962 ret = PTR_ERR(tctx->io_wq);
7963 percpu_counter_destroy(&tctx->inflight);
7964 kfree(tctx);
7965 return ret;
7966 }
7967
0f212204
JA
7968 xa_init(&tctx->xa);
7969 init_waitqueue_head(&tctx->wait);
7970 tctx->last = NULL;
fdaf083c 7971 atomic_set(&tctx->in_idle, 0);
0f212204 7972 task->io_uring = tctx;
7cbf1722
JA
7973 spin_lock_init(&tctx->task_lock);
7974 INIT_WQ_LIST(&tctx->task_list);
7975 tctx->task_state = 0;
7976 init_task_work(&tctx->task_work, tctx_task_work);
0f212204
JA
7977 return 0;
7978}
7979
7980void __io_uring_free(struct task_struct *tsk)
7981{
7982 struct io_uring_task *tctx = tsk->io_uring;
7983
7984 WARN_ON_ONCE(!xa_empty(&tctx->xa));
ef8eaa4e
PB
7985 WARN_ON_ONCE(tctx->io_wq);
7986
d8a6df10 7987 percpu_counter_destroy(&tctx->inflight);
0f212204
JA
7988 kfree(tctx);
7989 tsk->io_uring = NULL;
7990}
7991
7e84e1c7
SG
7992static int io_sq_offload_create(struct io_ring_ctx *ctx,
7993 struct io_uring_params *p)
2b188cc1
JA
7994{
7995 int ret;
7996
d25e3a3d
JA
7997 /* Retain compatibility with failing for an invalid attach attempt */
7998 if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
7999 IORING_SETUP_ATTACH_WQ) {
8000 struct fd f;
8001
8002 f = fdget(p->wq_fd);
8003 if (!f.file)
8004 return -ENXIO;
8005 if (f.file->f_op != &io_uring_fops) {
8006 fdput(f);
8007 return -EINVAL;
8008 }
8009 fdput(f);
8010 }
6c271ce2 8011 if (ctx->flags & IORING_SETUP_SQPOLL) {
46fe18b1 8012 struct task_struct *tsk;
534ca6d6 8013 struct io_sq_data *sqd;
26984fbf 8014 bool attached;
534ca6d6 8015
26984fbf 8016 sqd = io_get_sq_data(p, &attached);
534ca6d6
JA
8017 if (IS_ERR(sqd)) {
8018 ret = PTR_ERR(sqd);
8019 goto err;
8020 }
69fb2131 8021
7c30f36a 8022 ctx->sq_creds = get_current_cred();
534ca6d6 8023 ctx->sq_data = sqd;
917257da
JA
8024 ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
8025 if (!ctx->sq_thread_idle)
8026 ctx->sq_thread_idle = HZ;
8027
26984fbf 8028 ret = 0;
78d7f6ba 8029 io_sq_thread_park(sqd);
de75a3d3
PB
8030 list_add(&ctx->sqd_list, &sqd->ctx_list);
8031 io_sqd_update_thread_idle(sqd);
26984fbf 8032 /* don't attach to a dying SQPOLL thread, would be racy */
de75a3d3 8033 if (attached && !sqd->thread)
26984fbf 8034 ret = -ENXIO;
78d7f6ba
PB
8035 io_sq_thread_unpark(sqd);
8036
de75a3d3
PB
8037 if (ret < 0)
8038 goto err;
8039 if (attached)
5aa75ed5 8040 return 0;
aa06165d 8041
6c271ce2 8042 if (p->flags & IORING_SETUP_SQ_AFF) {
44a9bd18 8043 int cpu = p->sq_thread_cpu;
6c271ce2 8044
917257da 8045 ret = -EINVAL;
44a9bd18 8046 if (cpu >= nr_cpu_ids)
e8f98f24 8047 goto err_sqpoll;
7889f44d 8048 if (!cpu_online(cpu))
e8f98f24 8049 goto err_sqpoll;
917257da 8050
37d1e2e3 8051 sqd->sq_cpu = cpu;
6c271ce2 8052 } else {
37d1e2e3 8053 sqd->sq_cpu = -1;
6c271ce2 8054 }
37d1e2e3
JA
8055
8056 sqd->task_pid = current->pid;
5c2469e0 8057 sqd->task_tgid = current->tgid;
46fe18b1
JA
8058 tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
8059 if (IS_ERR(tsk)) {
8060 ret = PTR_ERR(tsk);
e8f98f24 8061 goto err_sqpoll;
6c271ce2 8062 }
97a73a0f 8063
46fe18b1 8064 sqd->thread = tsk;
97a73a0f 8065 ret = io_uring_alloc_task_context(tsk, ctx);
46fe18b1 8066 wake_up_new_task(tsk);
0f212204
JA
8067 if (ret)
8068 goto err;
6c271ce2
JA
8069 } else if (p->flags & IORING_SETUP_SQ_AFF) {
8070 /* Can't have SQ_AFF without SQPOLL */
8071 ret = -EINVAL;
8072 goto err;
8073 }
8074
2b188cc1
JA
8075 return 0;
8076err:
37d1e2e3 8077 io_sq_thread_finish(ctx);
2b188cc1 8078 return ret;
e8f98f24
JA
8079err_sqpoll:
8080 complete(&ctx->sq_data->exited);
8081 goto err;
2b188cc1
JA
8082}
8083
a087e2b5
BM
8084static inline void __io_unaccount_mem(struct user_struct *user,
8085 unsigned long nr_pages)
2b188cc1
JA
8086{
8087 atomic_long_sub(nr_pages, &user->locked_vm);
8088}
8089
a087e2b5
BM
8090static inline int __io_account_mem(struct user_struct *user,
8091 unsigned long nr_pages)
2b188cc1
JA
8092{
8093 unsigned long page_limit, cur_pages, new_pages;
8094
8095 /* Don't allow more pages than we can safely lock */
8096 page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
8097
8098 do {
8099 cur_pages = atomic_long_read(&user->locked_vm);
8100 new_pages = cur_pages + nr_pages;
8101 if (new_pages > page_limit)
8102 return -ENOMEM;
8103 } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
8104 new_pages) != cur_pages);
8105
8106 return 0;
8107}
8108
26bfa89e 8109static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
a087e2b5 8110{
62e398be 8111 if (ctx->user)
a087e2b5 8112 __io_unaccount_mem(ctx->user, nr_pages);
30975825 8113
26bfa89e
JA
8114 if (ctx->mm_account)
8115 atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
a087e2b5
BM
8116}
8117
26bfa89e 8118static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
a087e2b5 8119{
30975825
BM
8120 int ret;
8121
62e398be 8122 if (ctx->user) {
30975825
BM
8123 ret = __io_account_mem(ctx->user, nr_pages);
8124 if (ret)
8125 return ret;
8126 }
8127
26bfa89e
JA
8128 if (ctx->mm_account)
8129 atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
a087e2b5
BM
8130
8131 return 0;
8132}
8133
2b188cc1
JA
8134static void io_mem_free(void *ptr)
8135{
52e04ef4
MR
8136 struct page *page;
8137
8138 if (!ptr)
8139 return;
2b188cc1 8140
52e04ef4 8141 page = virt_to_head_page(ptr);
2b188cc1
JA
8142 if (put_page_testzero(page))
8143 free_compound_page(page);
8144}
8145
8146static void *io_mem_alloc(size_t size)
8147{
8148 gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP |
26bfa89e 8149 __GFP_NORETRY | __GFP_ACCOUNT;
2b188cc1
JA
8150
8151 return (void *) __get_free_pages(gfp_flags, get_order(size));
8152}
8153
75b28aff
HV
8154static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
8155 size_t *sq_offset)
8156{
8157 struct io_rings *rings;
8158 size_t off, sq_array_size;
8159
8160 off = struct_size(rings, cqes, cq_entries);
8161 if (off == SIZE_MAX)
8162 return SIZE_MAX;
8163
8164#ifdef CONFIG_SMP
8165 off = ALIGN(off, SMP_CACHE_BYTES);
8166 if (off == 0)
8167 return SIZE_MAX;
8168#endif
8169
b36200f5
DV
8170 if (sq_offset)
8171 *sq_offset = off;
8172
75b28aff
HV
8173 sq_array_size = array_size(sizeof(u32), sq_entries);
8174 if (sq_array_size == SIZE_MAX)
8175 return SIZE_MAX;
8176
8177 if (check_add_overflow(off, sq_array_size, &off))
8178 return SIZE_MAX;
8179
75b28aff
HV
8180 return off;
8181}
8182
0a96bbe4 8183static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
edafccee
JA
8184{
8185 int i, j;
8186
8187 if (!ctx->user_bufs)
8188 return -ENXIO;
8189
8190 for (i = 0; i < ctx->nr_user_bufs; i++) {
8191 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
8192
8193 for (j = 0; j < imu->nr_bvecs; j++)
f1f6a7dd 8194 unpin_user_page(imu->bvec[j].bv_page);
edafccee 8195
de293938 8196 if (imu->acct_pages)
26bfa89e 8197 io_unaccount_mem(ctx, imu->acct_pages);
d4ef6475 8198 kvfree(imu->bvec);
edafccee
JA
8199 imu->nr_bvecs = 0;
8200 }
8201
8202 kfree(ctx->user_bufs);
8203 ctx->user_bufs = NULL;
8204 ctx->nr_user_bufs = 0;
8205 return 0;
8206}
8207
8208static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
8209 void __user *arg, unsigned index)
8210{
8211 struct iovec __user *src;
8212
8213#ifdef CONFIG_COMPAT
8214 if (ctx->compat) {
8215 struct compat_iovec __user *ciovs;
8216 struct compat_iovec ciov;
8217
8218 ciovs = (struct compat_iovec __user *) arg;
8219 if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
8220 return -EFAULT;
8221
d55e5f5b 8222 dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
edafccee
JA
8223 dst->iov_len = ciov.iov_len;
8224 return 0;
8225 }
8226#endif
8227 src = (struct iovec __user *) arg;
8228 if (copy_from_user(dst, &src[index], sizeof(*dst)))
8229 return -EFAULT;
8230 return 0;
8231}
8232
de293938
JA
8233/*
8234 * Not super efficient, but this is just a registration time. And we do cache
8235 * the last compound head, so generally we'll only do a full search if we don't
8236 * match that one.
8237 *
8238 * We check if the given compound head page has already been accounted, to
8239 * avoid double accounting it. This allows us to account the full size of the
8240 * page, not just the constituent pages of a huge page.
8241 */
8242static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
8243 int nr_pages, struct page *hpage)
8244{
8245 int i, j;
8246
8247 /* check current page array */
8248 for (i = 0; i < nr_pages; i++) {
8249 if (!PageCompound(pages[i]))
8250 continue;
8251 if (compound_head(pages[i]) == hpage)
8252 return true;
8253 }
8254
8255 /* check previously registered pages */
8256 for (i = 0; i < ctx->nr_user_bufs; i++) {
8257 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
8258
8259 for (j = 0; j < imu->nr_bvecs; j++) {
8260 if (!PageCompound(imu->bvec[j].bv_page))
8261 continue;
8262 if (compound_head(imu->bvec[j].bv_page) == hpage)
8263 return true;
8264 }
8265 }
8266
8267 return false;
8268}
8269
8270static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
8271 int nr_pages, struct io_mapped_ubuf *imu,
8272 struct page **last_hpage)
8273{
8274 int i, ret;
8275
8276 for (i = 0; i < nr_pages; i++) {
8277 if (!PageCompound(pages[i])) {
8278 imu->acct_pages++;
8279 } else {
8280 struct page *hpage;
8281
8282 hpage = compound_head(pages[i]);
8283 if (hpage == *last_hpage)
8284 continue;
8285 *last_hpage = hpage;
8286 if (headpage_already_acct(ctx, pages, i, hpage))
8287 continue;
8288 imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
8289 }
8290 }
8291
8292 if (!imu->acct_pages)
8293 return 0;
8294
26bfa89e 8295 ret = io_account_mem(ctx, imu->acct_pages);
de293938
JA
8296 if (ret)
8297 imu->acct_pages = 0;
8298 return ret;
8299}
8300
0a96bbe4
BM
8301static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
8302 struct io_mapped_ubuf *imu,
8303 struct page **last_hpage)
edafccee
JA
8304{
8305 struct vm_area_struct **vmas = NULL;
8306 struct page **pages = NULL;
0a96bbe4
BM
8307 unsigned long off, start, end, ubuf;
8308 size_t size;
8309 int ret, pret, nr_pages, i;
8310
8311 ubuf = (unsigned long) iov->iov_base;
8312 end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
8313 start = ubuf >> PAGE_SHIFT;
8314 nr_pages = end - start;
8315
8316 ret = -ENOMEM;
8317
8318 pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
8319 if (!pages)
8320 goto done;
8321
8322 vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
8323 GFP_KERNEL);
8324 if (!vmas)
8325 goto done;
edafccee 8326
0a96bbe4
BM
8327 imu->bvec = kvmalloc_array(nr_pages, sizeof(struct bio_vec),
8328 GFP_KERNEL);
8329 if (!imu->bvec)
8330 goto done;
8331
8332 ret = 0;
8333 mmap_read_lock(current->mm);
8334 pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
8335 pages, vmas);
8336 if (pret == nr_pages) {
8337 /* don't support file backed memory */
8338 for (i = 0; i < nr_pages; i++) {
8339 struct vm_area_struct *vma = vmas[i];
8340
8341 if (vma->vm_file &&
8342 !is_file_hugepages(vma->vm_file)) {
8343 ret = -EOPNOTSUPP;
8344 break;
8345 }
8346 }
8347 } else {
8348 ret = pret < 0 ? pret : -EFAULT;
8349 }
8350 mmap_read_unlock(current->mm);
8351 if (ret) {
8352 /*
8353 * if we did partial map, or found file backed vmas,
8354 * release any pages we did get
8355 */
8356 if (pret > 0)
8357 unpin_user_pages(pages, pret);
8358 kvfree(imu->bvec);
8359 goto done;
8360 }
8361
8362 ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage);
8363 if (ret) {
8364 unpin_user_pages(pages, pret);
8365 kvfree(imu->bvec);
8366 goto done;
8367 }
8368
8369 off = ubuf & ~PAGE_MASK;
8370 size = iov->iov_len;
8371 for (i = 0; i < nr_pages; i++) {
8372 size_t vec_len;
8373
8374 vec_len = min_t(size_t, size, PAGE_SIZE - off);
8375 imu->bvec[i].bv_page = pages[i];
8376 imu->bvec[i].bv_len = vec_len;
8377 imu->bvec[i].bv_offset = off;
8378 off = 0;
8379 size -= vec_len;
8380 }
8381 /* store original address for later verification */
8382 imu->ubuf = ubuf;
8383 imu->len = iov->iov_len;
8384 imu->nr_bvecs = nr_pages;
8385 ret = 0;
8386done:
8387 kvfree(pages);
8388 kvfree(vmas);
8389 return ret;
8390}
8391
2b358604 8392static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
0a96bbe4 8393{
edafccee
JA
8394 if (ctx->user_bufs)
8395 return -EBUSY;
8396 if (!nr_args || nr_args > UIO_MAXIOV)
8397 return -EINVAL;
8398
8399 ctx->user_bufs = kcalloc(nr_args, sizeof(struct io_mapped_ubuf),
8400 GFP_KERNEL);
8401 if (!ctx->user_bufs)
8402 return -ENOMEM;
8403
2b358604
BM
8404 return 0;
8405}
edafccee 8406
2b358604
BM
8407static int io_buffer_validate(struct iovec *iov)
8408{
50e96989
PB
8409 unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1);
8410
2b358604
BM
8411 /*
8412 * Don't impose further limits on the size and buffer
8413 * constraints here, we'll -EINVAL later when IO is
8414 * submitted if they are wrong.
8415 */
8416 if (!iov->iov_base || !iov->iov_len)
8417 return -EFAULT;
edafccee 8418
2b358604
BM
8419 /* arbitrary limit, but we need something */
8420 if (iov->iov_len > SZ_1G)
8421 return -EFAULT;
edafccee 8422
50e96989
PB
8423 if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp))
8424 return -EOVERFLOW;
8425
2b358604
BM
8426 return 0;
8427}
edafccee 8428
2b358604
BM
8429static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
8430 unsigned int nr_args)
8431{
8432 int i, ret;
8433 struct iovec iov;
8434 struct page *last_hpage = NULL;
edafccee 8435
2b358604
BM
8436 ret = io_buffers_map_alloc(ctx, nr_args);
8437 if (ret)
8438 return ret;
edafccee 8439
edafccee
JA
8440 for (i = 0; i < nr_args; i++) {
8441 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
edafccee 8442
edafccee
JA
8443 ret = io_copy_iov(ctx, &iov, arg, i);
8444 if (ret)
0a96bbe4 8445 break;
de293938 8446
2b358604
BM
8447 ret = io_buffer_validate(&iov);
8448 if (ret)
0a96bbe4 8449 break;
edafccee 8450
0a96bbe4
BM
8451 ret = io_sqe_buffer_register(ctx, &iov, imu, &last_hpage);
8452 if (ret)
8453 break;
edafccee
JA
8454
8455 ctx->nr_user_bufs++;
8456 }
0a96bbe4
BM
8457
8458 if (ret)
8459 io_sqe_buffers_unregister(ctx);
8460
edafccee
JA
8461 return ret;
8462}
8463
9b402849
JA
8464static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
8465{
8466 __s32 __user *fds = arg;
8467 int fd;
8468
8469 if (ctx->cq_ev_fd)
8470 return -EBUSY;
8471
8472 if (copy_from_user(&fd, fds, sizeof(*fds)))
8473 return -EFAULT;
8474
8475 ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
8476 if (IS_ERR(ctx->cq_ev_fd)) {
8477 int ret = PTR_ERR(ctx->cq_ev_fd);
8478 ctx->cq_ev_fd = NULL;
8479 return ret;
8480 }
8481
8482 return 0;
8483}
8484
8485static int io_eventfd_unregister(struct io_ring_ctx *ctx)
8486{
8487 if (ctx->cq_ev_fd) {
8488 eventfd_ctx_put(ctx->cq_ev_fd);
8489 ctx->cq_ev_fd = NULL;
8490 return 0;
8491 }
8492
8493 return -ENXIO;
8494}
8495
5a2e745d
JA
8496static void io_destroy_buffers(struct io_ring_ctx *ctx)
8497{
9e15c3a0
JA
8498 struct io_buffer *buf;
8499 unsigned long index;
8500
8501 xa_for_each(&ctx->io_buffers, index, buf)
8502 __io_remove_buffers(ctx, buf, index, -1U);
5a2e745d
JA
8503}
8504
68e68ee6 8505static void io_req_cache_free(struct list_head *list, struct task_struct *tsk)
1b4c351f 8506{
68e68ee6 8507 struct io_kiocb *req, *nxt;
1b4c351f 8508
68e68ee6
JA
8509 list_for_each_entry_safe(req, nxt, list, compl.list) {
8510 if (tsk && req->task != tsk)
8511 continue;
1b4c351f
JA
8512 list_del(&req->compl.list);
8513 kmem_cache_free(req_cachep, req);
8514 }
8515}
8516
4010fec4 8517static void io_req_caches_free(struct io_ring_ctx *ctx)
2b188cc1 8518{
bf019da7 8519 struct io_submit_state *submit_state = &ctx->submit_state;
e5547d2c 8520 struct io_comp_state *cs = &ctx->submit_state.comp;
bf019da7 8521
9a4fdbd8
JA
8522 mutex_lock(&ctx->uring_lock);
8523
8e5c66c4 8524 if (submit_state->free_reqs) {
9a4fdbd8
JA
8525 kmem_cache_free_bulk(req_cachep, submit_state->free_reqs,
8526 submit_state->reqs);
8e5c66c4
PB
8527 submit_state->free_reqs = 0;
8528 }
9a4fdbd8 8529
dac7a098 8530 io_flush_cached_locked_reqs(ctx, cs);
e5547d2c 8531 io_req_cache_free(&cs->free_list, NULL);
9a4fdbd8
JA
8532 mutex_unlock(&ctx->uring_lock);
8533}
8534
2b188cc1
JA
8535static void io_ring_ctx_free(struct io_ring_ctx *ctx)
8536{
04fc6c80
PB
8537 /*
8538 * Some may use context even when all refs and requests have been put,
180f829f
PB
8539 * and they are free to do so while still holding uring_lock or
8540 * completion_lock, see __io_req_task_submit(). Wait for them to finish.
04fc6c80
PB
8541 */
8542 mutex_lock(&ctx->uring_lock);
8543 mutex_unlock(&ctx->uring_lock);
180f829f
PB
8544 spin_lock_irq(&ctx->completion_lock);
8545 spin_unlock_irq(&ctx->completion_lock);
04fc6c80 8546
37d1e2e3 8547 io_sq_thread_finish(ctx);
0a96bbe4 8548 io_sqe_buffers_unregister(ctx);
2aede0e4 8549
37d1e2e3 8550 if (ctx->mm_account) {
2aede0e4
JA
8551 mmdrop(ctx->mm_account);
8552 ctx->mm_account = NULL;
30975825 8553 }
def596e9 8554
8bad28d8 8555 mutex_lock(&ctx->uring_lock);
6b06314c 8556 io_sqe_files_unregister(ctx);
8bad28d8 8557 mutex_unlock(&ctx->uring_lock);
9b402849 8558 io_eventfd_unregister(ctx);
5a2e745d 8559 io_destroy_buffers(ctx);
def596e9 8560
8dd03afe
PB
8561 if (ctx->rsrc_backup_node)
8562 destroy_fixed_rsrc_ref_node(ctx->rsrc_backup_node);
8563
2b188cc1 8564#if defined(CONFIG_UNIX)
355e8d26
EB
8565 if (ctx->ring_sock) {
8566 ctx->ring_sock->file = NULL; /* so that iput() is called */
2b188cc1 8567 sock_release(ctx->ring_sock);
355e8d26 8568 }
2b188cc1
JA
8569#endif
8570
75b28aff 8571 io_mem_free(ctx->rings);
2b188cc1 8572 io_mem_free(ctx->sq_sqes);
2b188cc1
JA
8573
8574 percpu_ref_exit(&ctx->refs);
2b188cc1 8575 free_uid(ctx->user);
4010fec4 8576 io_req_caches_free(ctx);
e941894e
JA
8577 if (ctx->hash_map)
8578 io_wq_put_hash(ctx->hash_map);
78076bb6 8579 kfree(ctx->cancel_hash);
2b188cc1
JA
8580 kfree(ctx);
8581}
8582
8583static __poll_t io_uring_poll(struct file *file, poll_table *wait)
8584{
8585 struct io_ring_ctx *ctx = file->private_data;
8586 __poll_t mask = 0;
8587
8588 poll_wait(file, &ctx->cq_wait, wait);
4f7067c3
SB
8589 /*
8590 * synchronizes with barrier from wq_has_sleeper call in
8591 * io_commit_cqring
8592 */
2b188cc1 8593 smp_rmb();
90554200 8594 if (!io_sqring_full(ctx))
2b188cc1 8595 mask |= EPOLLOUT | EPOLLWRNORM;
ed670c3f
HX
8596
8597 /*
8598 * Don't flush cqring overflow list here, just do a simple check.
8599 * Otherwise there could possible be ABBA deadlock:
8600 * CPU0 CPU1
8601 * ---- ----
8602 * lock(&ctx->uring_lock);
8603 * lock(&ep->mtx);
8604 * lock(&ctx->uring_lock);
8605 * lock(&ep->mtx);
8606 *
8607 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
8608 * pushs them to do the flush.
8609 */
8610 if (io_cqring_events(ctx) || test_bit(0, &ctx->cq_check_overflow))
2b188cc1
JA
8611 mask |= EPOLLIN | EPOLLRDNORM;
8612
8613 return mask;
8614}
8615
8616static int io_uring_fasync(int fd, struct file *file, int on)
8617{
8618 struct io_ring_ctx *ctx = file->private_data;
8619
8620 return fasync_helper(fd, file, on, &ctx->cq_fasync);
8621}
8622
0bead8cd 8623static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
071698e1 8624{
4379bf8b 8625 const struct cred *creds;
071698e1 8626
61cf9370 8627 creds = xa_erase(&ctx->personalities, id);
4379bf8b
JA
8628 if (creds) {
8629 put_cred(creds);
0bead8cd 8630 return 0;
1e6fa521 8631 }
0bead8cd
YD
8632
8633 return -EINVAL;
8634}
8635
9b465711 8636static inline bool io_run_ctx_fallback(struct io_ring_ctx *ctx)
7c25c0d1 8637{
9b465711 8638 return io_run_task_work_head(&ctx->exit_task_work);
7c25c0d1
JA
8639}
8640
d56d938b
PB
8641struct io_tctx_exit {
8642 struct callback_head task_work;
8643 struct completion completion;
baf186c4 8644 struct io_ring_ctx *ctx;
d56d938b
PB
8645};
8646
8647static void io_tctx_exit_cb(struct callback_head *cb)
8648{
8649 struct io_uring_task *tctx = current->io_uring;
8650 struct io_tctx_exit *work;
8651
8652 work = container_of(cb, struct io_tctx_exit, task_work);
8653 /*
8654 * When @in_idle, we're in cancellation and it's racy to remove the
8655 * node. It'll be removed by the end of cancellation, just ignore it.
8656 */
8657 if (!atomic_read(&tctx->in_idle))
baf186c4 8658 io_uring_del_task_file((unsigned long)work->ctx);
d56d938b
PB
8659 complete(&work->completion);
8660}
8661
85faa7b8
JA
8662static void io_ring_exit_work(struct work_struct *work)
8663{
d56d938b 8664 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
b5bb3a24 8665 unsigned long timeout = jiffies + HZ * 60 * 5;
d56d938b
PB
8666 struct io_tctx_exit exit;
8667 struct io_tctx_node *node;
8668 int ret;
85faa7b8 8669
a185f1db
PB
8670 /* prevent SQPOLL from submitting new requests */
8671 if (ctx->sq_data) {
8672 io_sq_thread_park(ctx->sq_data);
8673 list_del_init(&ctx->sqd_list);
8674 io_sqd_update_thread_idle(ctx->sq_data);
8675 io_sq_thread_unpark(ctx->sq_data);
8676 }
8677
56952e91
JA
8678 /*
8679 * If we're doing polled IO and end up having requests being
8680 * submitted async (out-of-line), then completions can come in while
8681 * we're waiting for refs to drop. We need to reap these manually,
8682 * as nobody else will be looking for them.
8683 */
b2edc0a7 8684 do {
9936c7c2 8685 io_uring_try_cancel_requests(ctx, NULL, NULL);
b5bb3a24
PB
8686
8687 WARN_ON_ONCE(time_after(jiffies, timeout));
b2edc0a7 8688 } while (!wait_for_completion_timeout(&ctx->ref_comp, HZ/20));
d56d938b
PB
8689
8690 mutex_lock(&ctx->uring_lock);
8691 while (!list_empty(&ctx->tctx_list)) {
b5bb3a24
PB
8692 WARN_ON_ONCE(time_after(jiffies, timeout));
8693
d56d938b
PB
8694 node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
8695 ctx_node);
baf186c4 8696 exit.ctx = ctx;
d56d938b
PB
8697 init_completion(&exit.completion);
8698 init_task_work(&exit.task_work, io_tctx_exit_cb);
8699 ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
8700 if (WARN_ON_ONCE(ret))
8701 continue;
8702 wake_up_process(node->task);
8703
8704 mutex_unlock(&ctx->uring_lock);
8705 wait_for_completion(&exit.completion);
8706 cond_resched();
8707 mutex_lock(&ctx->uring_lock);
8708 }
8709 mutex_unlock(&ctx->uring_lock);
8710
85faa7b8
JA
8711 io_ring_ctx_free(ctx);
8712}
8713
80c4cbdb
PB
8714/* Returns true if we found and killed one or more timeouts */
8715static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
8716 struct files_struct *files)
8717{
8718 struct io_kiocb *req, *tmp;
8719 int canceled = 0;
8720
8721 spin_lock_irq(&ctx->completion_lock);
8722 list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
8723 if (io_match_task(req, tsk, files)) {
8724 io_kill_timeout(req, -ECANCELED);
8725 canceled++;
8726 }
8727 }
51520426
PB
8728 if (canceled != 0)
8729 io_commit_cqring(ctx);
80c4cbdb 8730 spin_unlock_irq(&ctx->completion_lock);
80c4cbdb
PB
8731 if (canceled != 0)
8732 io_cqring_ev_posted(ctx);
8733 return canceled != 0;
8734}
8735
2b188cc1
JA
8736static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
8737{
61cf9370
MWO
8738 unsigned long index;
8739 struct creds *creds;
8740
2b188cc1
JA
8741 mutex_lock(&ctx->uring_lock);
8742 percpu_ref_kill(&ctx->refs);
cda286f0
PB
8743 /* if force is set, the ring is going away. always drop after that */
8744 ctx->cq_overflow_flushed = 1;
634578f8 8745 if (ctx->rings)
6c2450ae 8746 __io_cqring_overflow_flush(ctx, true);
61cf9370
MWO
8747 xa_for_each(&ctx->personalities, index, creds)
8748 io_unregister_personality(ctx, index);
2b188cc1
JA
8749 mutex_unlock(&ctx->uring_lock);
8750
6b81928d
PB
8751 io_kill_timeouts(ctx, NULL, NULL);
8752 io_poll_remove_all(ctx, NULL, NULL);
561fb04a 8753
15dff286 8754 /* if we failed setting up the ctx, we might not have any rings */
b2edc0a7 8755 io_iopoll_try_reap_events(ctx);
309fc03a 8756
85faa7b8 8757 INIT_WORK(&ctx->exit_work, io_ring_exit_work);
fc666777
JA
8758 /*
8759 * Use system_unbound_wq to avoid spawning tons of event kworkers
8760 * if we're exiting a ton of rings at the same time. It just adds
8761 * noise and overhead, there's no discernable change in runtime
8762 * over using system_wq.
8763 */
8764 queue_work(system_unbound_wq, &ctx->exit_work);
2b188cc1
JA
8765}
8766
8767static int io_uring_release(struct inode *inode, struct file *file)
8768{
8769 struct io_ring_ctx *ctx = file->private_data;
8770
8771 file->private_data = NULL;
8772 io_ring_ctx_wait_and_kill(ctx);
8773 return 0;
8774}
8775
f6edbabb
PB
8776struct io_task_cancel {
8777 struct task_struct *task;
8778 struct files_struct *files;
8779};
f254ac04 8780
f6edbabb 8781static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
b711d4ea 8782{
9a472ef7 8783 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
f6edbabb 8784 struct io_task_cancel *cancel = data;
9a472ef7
PB
8785 bool ret;
8786
f6edbabb 8787 if (cancel->files && (req->flags & REQ_F_LINK_TIMEOUT)) {
9a472ef7
PB
8788 unsigned long flags;
8789 struct io_ring_ctx *ctx = req->ctx;
8790
8791 /* protect against races with linked timeouts */
8792 spin_lock_irqsave(&ctx->completion_lock, flags);
f6edbabb 8793 ret = io_match_task(req, cancel->task, cancel->files);
9a472ef7
PB
8794 spin_unlock_irqrestore(&ctx->completion_lock, flags);
8795 } else {
f6edbabb 8796 ret = io_match_task(req, cancel->task, cancel->files);
9a472ef7
PB
8797 }
8798 return ret;
b711d4ea
JA
8799}
8800
e1915f76 8801static bool io_cancel_defer_files(struct io_ring_ctx *ctx,
ef9865a4 8802 struct task_struct *task,
b7ddce3c
PB
8803 struct files_struct *files)
8804{
e1915f76 8805 struct io_defer_entry *de;
b7ddce3c
PB
8806 LIST_HEAD(list);
8807
8808 spin_lock_irq(&ctx->completion_lock);
8809 list_for_each_entry_reverse(de, &ctx->defer_list, list) {
08d23634 8810 if (io_match_task(de->req, task, files)) {
b7ddce3c
PB
8811 list_cut_position(&list, &ctx->defer_list, &de->list);
8812 break;
8813 }
8814 }
8815 spin_unlock_irq(&ctx->completion_lock);
e1915f76
PB
8816 if (list_empty(&list))
8817 return false;
b7ddce3c
PB
8818
8819 while (!list_empty(&list)) {
8820 de = list_first_entry(&list, struct io_defer_entry, list);
8821 list_del_init(&de->list);
f41db273 8822 io_req_complete_failed(de->req, -ECANCELED);
b7ddce3c
PB
8823 kfree(de);
8824 }
e1915f76 8825 return true;
b7ddce3c
PB
8826}
8827
1b00764f
PB
8828static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
8829{
8830 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8831
8832 return req->ctx == data;
8833}
8834
8835static bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
8836{
8837 struct io_tctx_node *node;
8838 enum io_wq_cancel cret;
8839 bool ret = false;
8840
8841 mutex_lock(&ctx->uring_lock);
8842 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
8843 struct io_uring_task *tctx = node->task->io_uring;
8844
8845 /*
8846 * io_wq will stay alive while we hold uring_lock, because it's
8847 * killed after ctx nodes, which requires to take the lock.
8848 */
8849 if (!tctx || !tctx->io_wq)
8850 continue;
8851 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
8852 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
8853 }
8854 mutex_unlock(&ctx->uring_lock);
8855
8856 return ret;
8857}
8858
9936c7c2
PB
8859static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
8860 struct task_struct *task,
8861 struct files_struct *files)
8862{
8863 struct io_task_cancel cancel = { .task = task, .files = files, };
1b00764f 8864 struct io_uring_task *tctx = task ? task->io_uring : NULL;
9936c7c2
PB
8865
8866 while (1) {
8867 enum io_wq_cancel cret;
8868 bool ret = false;
8869
1b00764f
PB
8870 if (!task) {
8871 ret |= io_uring_try_cancel_iowq(ctx);
8872 } else if (tctx && tctx->io_wq) {
8873 /*
8874 * Cancels requests of all rings, not only @ctx, but
8875 * it's fine as the task is in exit/exec.
8876 */
5aa75ed5 8877 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
9936c7c2
PB
8878 &cancel, true);
8879 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
8880 }
8881
8882 /* SQPOLL thread does its own polling */
d052d1d6
JA
8883 if ((!(ctx->flags & IORING_SETUP_SQPOLL) && !files) ||
8884 (ctx->sq_data && ctx->sq_data->thread == current)) {
9936c7c2
PB
8885 while (!list_empty_careful(&ctx->iopoll_list)) {
8886 io_iopoll_try_reap_events(ctx);
8887 ret = true;
8888 }
8889 }
8890
e1915f76 8891 ret |= io_cancel_defer_files(ctx, task, files);
9936c7c2
PB
8892 ret |= io_poll_remove_all(ctx, task, files);
8893 ret |= io_kill_timeouts(ctx, task, files);
8894 ret |= io_run_task_work();
ba50a036 8895 ret |= io_run_ctx_fallback(ctx);
9936c7c2
PB
8896 if (!ret)
8897 break;
8898 cond_resched();
8899 }
8900}
8901
ca70f00b
PB
8902static int io_uring_count_inflight(struct io_ring_ctx *ctx,
8903 struct task_struct *task,
8904 struct files_struct *files)
8905{
8906 struct io_kiocb *req;
8907 int cnt = 0;
8908
8909 spin_lock_irq(&ctx->inflight_lock);
8910 list_for_each_entry(req, &ctx->inflight_list, inflight_entry)
8911 cnt += io_match_task(req, task, files);
8912 spin_unlock_irq(&ctx->inflight_lock);
8913 return cnt;
8914}
8915
b52fda00 8916static void io_uring_cancel_files(struct io_ring_ctx *ctx,
df9923f9 8917 struct task_struct *task,
fcb323cc
JA
8918 struct files_struct *files)
8919{
fcb323cc 8920 while (!list_empty_careful(&ctx->inflight_list)) {
d8f1b971 8921 DEFINE_WAIT(wait);
ca70f00b 8922 int inflight;
fcb323cc 8923
ca70f00b
PB
8924 inflight = io_uring_count_inflight(ctx, task, files);
8925 if (!inflight)
fcb323cc 8926 break;
f6edbabb 8927
9936c7c2 8928 io_uring_try_cancel_requests(ctx, task, files);
ca70f00b
PB
8929
8930 prepare_to_wait(&task->io_uring->wait, &wait,
8931 TASK_UNINTERRUPTIBLE);
8932 if (inflight == io_uring_count_inflight(ctx, task, files))
8933 schedule();
c98de08c 8934 finish_wait(&task->io_uring->wait, &wait);
0f212204 8935 }
0f212204
JA
8936}
8937
cf27f3b1 8938static int __io_uring_add_task_file(struct io_ring_ctx *ctx)
0f212204 8939{
236434c3 8940 struct io_uring_task *tctx = current->io_uring;
13bf43f5 8941 struct io_tctx_node *node;
a528b04e 8942 int ret;
236434c3
MWO
8943
8944 if (unlikely(!tctx)) {
5aa75ed5 8945 ret = io_uring_alloc_task_context(current, ctx);
0f212204
JA
8946 if (unlikely(ret))
8947 return ret;
236434c3 8948 tctx = current->io_uring;
0f212204 8949 }
cf27f3b1
PB
8950 if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
8951 node = kmalloc(sizeof(*node), GFP_KERNEL);
8952 if (!node)
8953 return -ENOMEM;
8954 node->ctx = ctx;
8955 node->task = current;
13bf43f5 8956
cf27f3b1
PB
8957 ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
8958 node, GFP_KERNEL));
8959 if (ret) {
8960 kfree(node);
8961 return ret;
0f212204 8962 }
cf27f3b1
PB
8963
8964 mutex_lock(&ctx->uring_lock);
8965 list_add(&node->ctx_node, &ctx->tctx_list);
8966 mutex_unlock(&ctx->uring_lock);
0f212204 8967 }
cf27f3b1 8968 tctx->last = ctx;
0f212204
JA
8969 return 0;
8970}
8971
cf27f3b1
PB
8972/*
8973 * Note that this task has used io_uring. We use it for cancelation purposes.
8974 */
8975static inline int io_uring_add_task_file(struct io_ring_ctx *ctx)
8976{
8977 struct io_uring_task *tctx = current->io_uring;
8978
8979 if (likely(tctx && tctx->last == ctx))
8980 return 0;
8981 return __io_uring_add_task_file(ctx);
8982}
8983
0f212204
JA
8984/*
8985 * Remove this io_uring_file -> task mapping.
8986 */
2941267b 8987static void io_uring_del_task_file(unsigned long index)
0f212204
JA
8988{
8989 struct io_uring_task *tctx = current->io_uring;
13bf43f5 8990 struct io_tctx_node *node;
2941267b 8991
eebd2e37
PB
8992 if (!tctx)
8993 return;
13bf43f5
PB
8994 node = xa_erase(&tctx->xa, index);
8995 if (!node)
2941267b 8996 return;
0f212204 8997
13bf43f5
PB
8998 WARN_ON_ONCE(current != node->task);
8999 WARN_ON_ONCE(list_empty(&node->ctx_node));
9000
9001 mutex_lock(&node->ctx->uring_lock);
9002 list_del(&node->ctx_node);
9003 mutex_unlock(&node->ctx->uring_lock);
9004
baf186c4 9005 if (tctx->last == node->ctx)
0f212204 9006 tctx->last = NULL;
13bf43f5 9007 kfree(node);
0f212204
JA
9008}
9009
8452d4a6 9010static void io_uring_clean_tctx(struct io_uring_task *tctx)
de7f1d9e 9011{
13bf43f5 9012 struct io_tctx_node *node;
de7f1d9e
PB
9013 unsigned long index;
9014
13bf43f5 9015 xa_for_each(&tctx->xa, index, node)
2941267b 9016 io_uring_del_task_file(index);
8452d4a6
PB
9017 if (tctx->io_wq) {
9018 io_wq_put_and_exit(tctx->io_wq);
9019 tctx->io_wq = NULL;
9020 }
de7f1d9e
PB
9021}
9022
521d6a73
PB
9023static s64 tctx_inflight(struct io_uring_task *tctx)
9024{
9025 return percpu_counter_sum(&tctx->inflight);
9026}
9027
9028static void io_sqpoll_cancel_cb(struct callback_head *cb)
9029{
9030 struct io_tctx_exit *work = container_of(cb, struct io_tctx_exit, task_work);
9031 struct io_ring_ctx *ctx = work->ctx;
9032 struct io_sq_data *sqd = ctx->sq_data;
9033
9034 if (sqd->thread)
9035 io_uring_cancel_sqpoll(ctx);
9036 complete(&work->completion);
9037}
9038
9039static void io_sqpoll_cancel_sync(struct io_ring_ctx *ctx)
9040{
9041 struct io_sq_data *sqd = ctx->sq_data;
9042 struct io_tctx_exit work = { .ctx = ctx, };
9043 struct task_struct *task;
9044
9045 io_sq_thread_park(sqd);
9046 list_del_init(&ctx->sqd_list);
9047 io_sqd_update_thread_idle(sqd);
9048 task = sqd->thread;
9049 if (task) {
9050 init_completion(&work.completion);
9051 init_task_work(&work.task_work, io_sqpoll_cancel_cb);
b7f5a0bf 9052 io_task_work_add_head(&sqd->park_task_work, &work.task_work);
521d6a73
PB
9053 wake_up_process(task);
9054 }
9055 io_sq_thread_unpark(sqd);
9056
9057 if (task)
9058 wait_for_completion(&work.completion);
9059}
9060
0f212204
JA
9061void __io_uring_files_cancel(struct files_struct *files)
9062{
9063 struct io_uring_task *tctx = current->io_uring;
13bf43f5 9064 struct io_tctx_node *node;
ce765372 9065 unsigned long index;
0f212204
JA
9066
9067 /* make sure overflow events are dropped */
fdaf083c 9068 atomic_inc(&tctx->in_idle);
521d6a73
PB
9069 xa_for_each(&tctx->xa, index, node) {
9070 struct io_ring_ctx *ctx = node->ctx;
9071
9072 if (ctx->sq_data) {
9073 io_sqpoll_cancel_sync(ctx);
9074 continue;
9075 }
9076 io_uring_cancel_files(ctx, current, files);
9077 if (!files)
9078 io_uring_try_cancel_requests(ctx, current, NULL);
9079 }
fdaf083c 9080 atomic_dec(&tctx->in_idle);
de7f1d9e 9081
8452d4a6
PB
9082 if (files)
9083 io_uring_clean_tctx(tctx);
fdaf083c
JA
9084}
9085
521d6a73 9086/* should only be called by SQPOLL task */
0e9ddb39
PB
9087static void io_uring_cancel_sqpoll(struct io_ring_ctx *ctx)
9088{
37d1e2e3 9089 struct io_sq_data *sqd = ctx->sq_data;
521d6a73 9090 struct io_uring_task *tctx = current->io_uring;
0e9ddb39
PB
9091 s64 inflight;
9092 DEFINE_WAIT(wait);
fdaf083c 9093
521d6a73
PB
9094 WARN_ON_ONCE(!sqd || ctx->sq_data->thread != current);
9095
0e9ddb39
PB
9096 atomic_inc(&tctx->in_idle);
9097 do {
9098 /* read completions before cancelations */
9099 inflight = tctx_inflight(tctx);
9100 if (!inflight)
9101 break;
521d6a73 9102 io_uring_try_cancel_requests(ctx, current, NULL);
fdaf083c 9103
0e9ddb39
PB
9104 prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
9105 /*
9106 * If we've seen completions, retry without waiting. This
9107 * avoids a race where a completion comes in before we did
9108 * prepare_to_wait().
9109 */
9110 if (inflight == tctx_inflight(tctx))
9111 schedule();
9112 finish_wait(&tctx->wait, &wait);
9113 } while (1);
9114 atomic_dec(&tctx->in_idle);
0f212204
JA
9115}
9116
0f212204
JA
9117/*
9118 * Find any io_uring fd that this task has registered or done IO on, and cancel
9119 * requests.
9120 */
9121void __io_uring_task_cancel(void)
9122{
9123 struct io_uring_task *tctx = current->io_uring;
9124 DEFINE_WAIT(wait);
d8a6df10 9125 s64 inflight;
0f212204
JA
9126
9127 /* make sure overflow events are dropped */
fdaf083c 9128 atomic_inc(&tctx->in_idle);
5a978dcf
PB
9129 __io_uring_files_cancel(NULL);
9130
d8a6df10 9131 do {
0f212204 9132 /* read completions before cancelations */
fdaf083c 9133 inflight = tctx_inflight(tctx);
d8a6df10
JA
9134 if (!inflight)
9135 break;
0f212204
JA
9136 __io_uring_files_cancel(NULL);
9137
9138 prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
9139
9140 /*
a1bb3cd5
PB
9141 * If we've seen completions, retry without waiting. This
9142 * avoids a race where a completion comes in before we did
9143 * prepare_to_wait().
0f212204 9144 */
a1bb3cd5
PB
9145 if (inflight == tctx_inflight(tctx))
9146 schedule();
f57555ed 9147 finish_wait(&tctx->wait, &wait);
d8a6df10 9148 } while (1);
0f212204 9149
fdaf083c 9150 atomic_dec(&tctx->in_idle);
de7f1d9e 9151
8452d4a6
PB
9152 io_uring_clean_tctx(tctx);
9153 /* all current's requests should be gone, we can kill tctx */
9154 __io_uring_free(current);
44e728b8
PB
9155}
9156
6c5c240e
RP
9157static void *io_uring_validate_mmap_request(struct file *file,
9158 loff_t pgoff, size_t sz)
2b188cc1 9159{
2b188cc1 9160 struct io_ring_ctx *ctx = file->private_data;
6c5c240e 9161 loff_t offset = pgoff << PAGE_SHIFT;
2b188cc1
JA
9162 struct page *page;
9163 void *ptr;
9164
9165 switch (offset) {
9166 case IORING_OFF_SQ_RING:
75b28aff
HV
9167 case IORING_OFF_CQ_RING:
9168 ptr = ctx->rings;
2b188cc1
JA
9169 break;
9170 case IORING_OFF_SQES:
9171 ptr = ctx->sq_sqes;
9172 break;
2b188cc1 9173 default:
6c5c240e 9174 return ERR_PTR(-EINVAL);
2b188cc1
JA
9175 }
9176
9177 page = virt_to_head_page(ptr);
a50b854e 9178 if (sz > page_size(page))
6c5c240e
RP
9179 return ERR_PTR(-EINVAL);
9180
9181 return ptr;
9182}
9183
9184#ifdef CONFIG_MMU
9185
9186static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
9187{
9188 size_t sz = vma->vm_end - vma->vm_start;
9189 unsigned long pfn;
9190 void *ptr;
9191
9192 ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
9193 if (IS_ERR(ptr))
9194 return PTR_ERR(ptr);
2b188cc1
JA
9195
9196 pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
9197 return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
9198}
9199
6c5c240e
RP
9200#else /* !CONFIG_MMU */
9201
9202static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
9203{
9204 return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
9205}
9206
9207static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
9208{
9209 return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
9210}
9211
9212static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
9213 unsigned long addr, unsigned long len,
9214 unsigned long pgoff, unsigned long flags)
9215{
9216 void *ptr;
9217
9218 ptr = io_uring_validate_mmap_request(file, pgoff, len);
9219 if (IS_ERR(ptr))
9220 return PTR_ERR(ptr);
9221
9222 return (unsigned long) ptr;
9223}
9224
9225#endif /* !CONFIG_MMU */
9226
d9d05217 9227static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
90554200
JA
9228{
9229 DEFINE_WAIT(wait);
9230
9231 do {
9232 if (!io_sqring_full(ctx))
9233 break;
90554200
JA
9234 prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
9235
9236 if (!io_sqring_full(ctx))
9237 break;
90554200
JA
9238 schedule();
9239 } while (!signal_pending(current));
9240
9241 finish_wait(&ctx->sqo_sq_wait, &wait);
5199328a 9242 return 0;
90554200
JA
9243}
9244
c73ebb68
HX
9245static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
9246 struct __kernel_timespec __user **ts,
9247 const sigset_t __user **sig)
9248{
9249 struct io_uring_getevents_arg arg;
9250
9251 /*
9252 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9253 * is just a pointer to the sigset_t.
9254 */
9255 if (!(flags & IORING_ENTER_EXT_ARG)) {
9256 *sig = (const sigset_t __user *) argp;
9257 *ts = NULL;
9258 return 0;
9259 }
9260
9261 /*
9262 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9263 * timespec and sigset_t pointers if good.
9264 */
9265 if (*argsz != sizeof(arg))
9266 return -EINVAL;
9267 if (copy_from_user(&arg, argp, sizeof(arg)))
9268 return -EFAULT;
9269 *sig = u64_to_user_ptr(arg.sigmask);
9270 *argsz = arg.sigmask_sz;
9271 *ts = u64_to_user_ptr(arg.ts);
9272 return 0;
9273}
9274
2b188cc1 9275SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
c73ebb68
HX
9276 u32, min_complete, u32, flags, const void __user *, argp,
9277 size_t, argsz)
2b188cc1
JA
9278{
9279 struct io_ring_ctx *ctx;
2b188cc1
JA
9280 int submitted = 0;
9281 struct fd f;
33f993da 9282 long ret;
2b188cc1 9283
4c6e277c 9284 io_run_task_work();
b41e9852 9285
33f993da
PB
9286 if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
9287 IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG)))
2b188cc1
JA
9288 return -EINVAL;
9289
9290 f = fdget(fd);
33f993da 9291 if (unlikely(!f.file))
2b188cc1
JA
9292 return -EBADF;
9293
9294 ret = -EOPNOTSUPP;
33f993da 9295 if (unlikely(f.file->f_op != &io_uring_fops))
2b188cc1
JA
9296 goto out_fput;
9297
9298 ret = -ENXIO;
9299 ctx = f.file->private_data;
33f993da 9300 if (unlikely(!percpu_ref_tryget(&ctx->refs)))
2b188cc1
JA
9301 goto out_fput;
9302
7e84e1c7 9303 ret = -EBADFD;
33f993da 9304 if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED))
7e84e1c7
SG
9305 goto out;
9306
6c271ce2
JA
9307 /*
9308 * For SQ polling, the thread will do all submissions and completions.
9309 * Just return the requested submit count, and wake the thread if
9310 * we were asked to.
9311 */
b2a9eada 9312 ret = 0;
6c271ce2 9313 if (ctx->flags & IORING_SETUP_SQPOLL) {
6c2450ae 9314 io_cqring_overflow_flush(ctx, false);
89448c47 9315
d9d05217 9316 ret = -EOWNERDEAD;
04147488
SM
9317 if (unlikely(ctx->sq_data->thread == NULL)) {
9318 goto out;
9319 }
6c271ce2 9320 if (flags & IORING_ENTER_SQ_WAKEUP)
534ca6d6 9321 wake_up(&ctx->sq_data->wait);
d9d05217
PB
9322 if (flags & IORING_ENTER_SQ_WAIT) {
9323 ret = io_sqpoll_wait_sq(ctx);
9324 if (ret)
9325 goto out;
9326 }
6c271ce2 9327 submitted = to_submit;
b2a9eada 9328 } else if (to_submit) {
baf186c4 9329 ret = io_uring_add_task_file(ctx);
0f212204
JA
9330 if (unlikely(ret))
9331 goto out;
2b188cc1 9332 mutex_lock(&ctx->uring_lock);
0f212204 9333 submitted = io_submit_sqes(ctx, to_submit);
2b188cc1 9334 mutex_unlock(&ctx->uring_lock);
7c504e65
PB
9335
9336 if (submitted != to_submit)
9337 goto out;
2b188cc1
JA
9338 }
9339 if (flags & IORING_ENTER_GETEVENTS) {
c73ebb68
HX
9340 const sigset_t __user *sig;
9341 struct __kernel_timespec __user *ts;
9342
9343 ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
9344 if (unlikely(ret))
9345 goto out;
9346
2b188cc1
JA
9347 min_complete = min(min_complete, ctx->cq_entries);
9348
32b2244a
XW
9349 /*
9350 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9351 * space applications don't need to do io completion events
9352 * polling again, they can rely on io_sq_thread to do polling
9353 * work, which can reduce cpu usage and uring_lock contention.
9354 */
9355 if (ctx->flags & IORING_SETUP_IOPOLL &&
9356 !(ctx->flags & IORING_SETUP_SQPOLL)) {
7668b92a 9357 ret = io_iopoll_check(ctx, min_complete);
def596e9 9358 } else {
c73ebb68 9359 ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts);
def596e9 9360 }
2b188cc1
JA
9361 }
9362
7c504e65 9363out:
6805b32e 9364 percpu_ref_put(&ctx->refs);
2b188cc1
JA
9365out_fput:
9366 fdput(f);
9367 return submitted ? submitted : ret;
9368}
9369
bebdb65e 9370#ifdef CONFIG_PROC_FS
61cf9370
MWO
9371static int io_uring_show_cred(struct seq_file *m, unsigned int id,
9372 const struct cred *cred)
87ce955b 9373{
87ce955b
JA
9374 struct user_namespace *uns = seq_user_ns(m);
9375 struct group_info *gi;
9376 kernel_cap_t cap;
9377 unsigned __capi;
9378 int g;
9379
9380 seq_printf(m, "%5d\n", id);
9381 seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
9382 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
9383 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
9384 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
9385 seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
9386 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
9387 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
9388 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
9389 seq_puts(m, "\n\tGroups:\t");
9390 gi = cred->group_info;
9391 for (g = 0; g < gi->ngroups; g++) {
9392 seq_put_decimal_ull(m, g ? " " : "",
9393 from_kgid_munged(uns, gi->gid[g]));
9394 }
9395 seq_puts(m, "\n\tCapEff:\t");
9396 cap = cred->cap_effective;
9397 CAP_FOR_EACH_U32(__capi)
9398 seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
9399 seq_putc(m, '\n');
9400 return 0;
9401}
9402
9403static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
9404{
dbbe9c64 9405 struct io_sq_data *sq = NULL;
fad8e0de 9406 bool has_lock;
87ce955b
JA
9407 int i;
9408
fad8e0de
JA
9409 /*
9410 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9411 * since fdinfo case grabs it in the opposite direction of normal use
9412 * cases. If we fail to get the lock, we just don't iterate any
9413 * structures that could be going away outside the io_uring mutex.
9414 */
9415 has_lock = mutex_trylock(&ctx->uring_lock);
9416
5f3f26f9 9417 if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
dbbe9c64 9418 sq = ctx->sq_data;
5f3f26f9
JA
9419 if (!sq->thread)
9420 sq = NULL;
9421 }
dbbe9c64
JQ
9422
9423 seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
9424 seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
87ce955b 9425 seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
fad8e0de 9426 for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
7b29f92d 9427 struct file *f = io_file_from_index(ctx, i);
87ce955b 9428
87ce955b
JA
9429 if (f)
9430 seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
9431 else
9432 seq_printf(m, "%5u: <none>\n", i);
9433 }
9434 seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
fad8e0de 9435 for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
87ce955b
JA
9436 struct io_mapped_ubuf *buf = &ctx->user_bufs[i];
9437
9438 seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf,
9439 (unsigned int) buf->len);
9440 }
61cf9370
MWO
9441 if (has_lock && !xa_empty(&ctx->personalities)) {
9442 unsigned long index;
9443 const struct cred *cred;
9444
87ce955b 9445 seq_printf(m, "Personalities:\n");
61cf9370
MWO
9446 xa_for_each(&ctx->personalities, index, cred)
9447 io_uring_show_cred(m, index, cred);
87ce955b 9448 }
d7718a9d
JA
9449 seq_printf(m, "PollList:\n");
9450 spin_lock_irq(&ctx->completion_lock);
9451 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
9452 struct hlist_head *list = &ctx->cancel_hash[i];
9453 struct io_kiocb *req;
9454
9455 hlist_for_each_entry(req, list, hash_node)
9456 seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
9457 req->task->task_works != NULL);
9458 }
9459 spin_unlock_irq(&ctx->completion_lock);
fad8e0de
JA
9460 if (has_lock)
9461 mutex_unlock(&ctx->uring_lock);
87ce955b
JA
9462}
9463
9464static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
9465{
9466 struct io_ring_ctx *ctx = f->private_data;
9467
9468 if (percpu_ref_tryget(&ctx->refs)) {
9469 __io_uring_show_fdinfo(ctx, m);
9470 percpu_ref_put(&ctx->refs);
9471 }
9472}
bebdb65e 9473#endif
87ce955b 9474
2b188cc1
JA
9475static const struct file_operations io_uring_fops = {
9476 .release = io_uring_release,
9477 .mmap = io_uring_mmap,
6c5c240e
RP
9478#ifndef CONFIG_MMU
9479 .get_unmapped_area = io_uring_nommu_get_unmapped_area,
9480 .mmap_capabilities = io_uring_nommu_mmap_capabilities,
9481#endif
2b188cc1
JA
9482 .poll = io_uring_poll,
9483 .fasync = io_uring_fasync,
bebdb65e 9484#ifdef CONFIG_PROC_FS
87ce955b 9485 .show_fdinfo = io_uring_show_fdinfo,
bebdb65e 9486#endif
2b188cc1
JA
9487};
9488
9489static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
9490 struct io_uring_params *p)
9491{
75b28aff
HV
9492 struct io_rings *rings;
9493 size_t size, sq_array_offset;
2b188cc1 9494
bd740481
JA
9495 /* make sure these are sane, as we already accounted them */
9496 ctx->sq_entries = p->sq_entries;
9497 ctx->cq_entries = p->cq_entries;
9498
75b28aff
HV
9499 size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
9500 if (size == SIZE_MAX)
9501 return -EOVERFLOW;
9502
9503 rings = io_mem_alloc(size);
9504 if (!rings)
2b188cc1
JA
9505 return -ENOMEM;
9506
75b28aff
HV
9507 ctx->rings = rings;
9508 ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
9509 rings->sq_ring_mask = p->sq_entries - 1;
9510 rings->cq_ring_mask = p->cq_entries - 1;
9511 rings->sq_ring_entries = p->sq_entries;
9512 rings->cq_ring_entries = p->cq_entries;
9513 ctx->sq_mask = rings->sq_ring_mask;
9514 ctx->cq_mask = rings->cq_ring_mask;
2b188cc1
JA
9515
9516 size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
eb065d30
JA
9517 if (size == SIZE_MAX) {
9518 io_mem_free(ctx->rings);
9519 ctx->rings = NULL;
2b188cc1 9520 return -EOVERFLOW;
eb065d30 9521 }
2b188cc1
JA
9522
9523 ctx->sq_sqes = io_mem_alloc(size);
eb065d30
JA
9524 if (!ctx->sq_sqes) {
9525 io_mem_free(ctx->rings);
9526 ctx->rings = NULL;
2b188cc1 9527 return -ENOMEM;
eb065d30 9528 }
2b188cc1 9529
2b188cc1
JA
9530 return 0;
9531}
9532
9faadcc8
PB
9533static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
9534{
9535 int ret, fd;
9536
9537 fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
9538 if (fd < 0)
9539 return fd;
9540
baf186c4 9541 ret = io_uring_add_task_file(ctx);
9faadcc8
PB
9542 if (ret) {
9543 put_unused_fd(fd);
9544 return ret;
9545 }
9546 fd_install(fd, file);
9547 return fd;
9548}
9549
2b188cc1
JA
9550/*
9551 * Allocate an anonymous fd, this is what constitutes the application
9552 * visible backing of an io_uring instance. The application mmaps this
9553 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9554 * we have to tie this fd to a socket for file garbage collection purposes.
9555 */
9faadcc8 9556static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
2b188cc1
JA
9557{
9558 struct file *file;
9faadcc8 9559#if defined(CONFIG_UNIX)
2b188cc1
JA
9560 int ret;
9561
2b188cc1
JA
9562 ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
9563 &ctx->ring_sock);
9564 if (ret)
9faadcc8 9565 return ERR_PTR(ret);
2b188cc1
JA
9566#endif
9567
2b188cc1
JA
9568 file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
9569 O_RDWR | O_CLOEXEC);
2b188cc1 9570#if defined(CONFIG_UNIX)
9faadcc8
PB
9571 if (IS_ERR(file)) {
9572 sock_release(ctx->ring_sock);
9573 ctx->ring_sock = NULL;
9574 } else {
9575 ctx->ring_sock->file = file;
0f212204 9576 }
2b188cc1 9577#endif
9faadcc8 9578 return file;
2b188cc1
JA
9579}
9580
7f13657d
XW
9581static int io_uring_create(unsigned entries, struct io_uring_params *p,
9582 struct io_uring_params __user *params)
2b188cc1 9583{
2b188cc1 9584 struct io_ring_ctx *ctx;
9faadcc8 9585 struct file *file;
2b188cc1
JA
9586 int ret;
9587
8110c1a6 9588 if (!entries)
2b188cc1 9589 return -EINVAL;
8110c1a6
JA
9590 if (entries > IORING_MAX_ENTRIES) {
9591 if (!(p->flags & IORING_SETUP_CLAMP))
9592 return -EINVAL;
9593 entries = IORING_MAX_ENTRIES;
9594 }
2b188cc1
JA
9595
9596 /*
9597 * Use twice as many entries for the CQ ring. It's possible for the
9598 * application to drive a higher depth than the size of the SQ ring,
9599 * since the sqes are only used at submission time. This allows for
33a107f0
JA
9600 * some flexibility in overcommitting a bit. If the application has
9601 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9602 * of CQ ring entries manually.
2b188cc1
JA
9603 */
9604 p->sq_entries = roundup_pow_of_two(entries);
33a107f0
JA
9605 if (p->flags & IORING_SETUP_CQSIZE) {
9606 /*
9607 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9608 * to a power-of-two, if it isn't already. We do NOT impose
9609 * any cq vs sq ring sizing.
9610 */
eb2667b3 9611 if (!p->cq_entries)
33a107f0 9612 return -EINVAL;
8110c1a6
JA
9613 if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
9614 if (!(p->flags & IORING_SETUP_CLAMP))
9615 return -EINVAL;
9616 p->cq_entries = IORING_MAX_CQ_ENTRIES;
9617 }
eb2667b3
JQ
9618 p->cq_entries = roundup_pow_of_two(p->cq_entries);
9619 if (p->cq_entries < p->sq_entries)
9620 return -EINVAL;
33a107f0
JA
9621 } else {
9622 p->cq_entries = 2 * p->sq_entries;
9623 }
2b188cc1 9624
2b188cc1 9625 ctx = io_ring_ctx_alloc(p);
62e398be 9626 if (!ctx)
2b188cc1 9627 return -ENOMEM;
2b188cc1 9628 ctx->compat = in_compat_syscall();
62e398be
JA
9629 if (!capable(CAP_IPC_LOCK))
9630 ctx->user = get_uid(current_user());
2aede0e4
JA
9631
9632 /*
9633 * This is just grabbed for accounting purposes. When a process exits,
9634 * the mm is exited and dropped before the files, hence we need to hang
9635 * on to this mm purely for the purposes of being able to unaccount
9636 * memory (locked/pinned vm). It's not used for anything else.
9637 */
6b7898eb 9638 mmgrab(current->mm);
2aede0e4 9639 ctx->mm_account = current->mm;
6b7898eb 9640
2b188cc1
JA
9641 ret = io_allocate_scq_urings(ctx, p);
9642 if (ret)
9643 goto err;
9644
7e84e1c7 9645 ret = io_sq_offload_create(ctx, p);
2b188cc1
JA
9646 if (ret)
9647 goto err;
9648
2b188cc1 9649 memset(&p->sq_off, 0, sizeof(p->sq_off));
75b28aff
HV
9650 p->sq_off.head = offsetof(struct io_rings, sq.head);
9651 p->sq_off.tail = offsetof(struct io_rings, sq.tail);
9652 p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
9653 p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
9654 p->sq_off.flags = offsetof(struct io_rings, sq_flags);
9655 p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
9656 p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
2b188cc1
JA
9657
9658 memset(&p->cq_off, 0, sizeof(p->cq_off));
75b28aff
HV
9659 p->cq_off.head = offsetof(struct io_rings, cq.head);
9660 p->cq_off.tail = offsetof(struct io_rings, cq.tail);
9661 p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
9662 p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
9663 p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
9664 p->cq_off.cqes = offsetof(struct io_rings, cqes);
0d9b5b3a 9665 p->cq_off.flags = offsetof(struct io_rings, cq_flags);
ac90f249 9666
7f13657d
XW
9667 p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
9668 IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
5769a351 9669 IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
c73ebb68 9670 IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
1c0aa1fa 9671 IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS;
7f13657d
XW
9672
9673 if (copy_to_user(params, p, sizeof(*p))) {
9674 ret = -EFAULT;
9675 goto err;
9676 }
d1719f70 9677
9faadcc8
PB
9678 file = io_uring_get_file(ctx);
9679 if (IS_ERR(file)) {
9680 ret = PTR_ERR(file);
9681 goto err;
9682 }
9683
044c1ab3
JA
9684 /*
9685 * Install ring fd as the very last thing, so we don't risk someone
9686 * having closed it before we finish setup
9687 */
9faadcc8
PB
9688 ret = io_uring_install_fd(ctx, file);
9689 if (ret < 0) {
9690 /* fput will clean it up */
9691 fput(file);
9692 return ret;
9693 }
044c1ab3 9694
c826bd7a 9695 trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
2b188cc1
JA
9696 return ret;
9697err:
9698 io_ring_ctx_wait_and_kill(ctx);
9699 return ret;
9700}
9701
9702/*
9703 * Sets up an aio uring context, and returns the fd. Applications asks for a
9704 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9705 * params structure passed in.
9706 */
9707static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
9708{
9709 struct io_uring_params p;
2b188cc1
JA
9710 int i;
9711
9712 if (copy_from_user(&p, params, sizeof(p)))
9713 return -EFAULT;
9714 for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
9715 if (p.resv[i])
9716 return -EINVAL;
9717 }
9718
6c271ce2 9719 if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
8110c1a6 9720 IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
7e84e1c7
SG
9721 IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
9722 IORING_SETUP_R_DISABLED))
2b188cc1
JA
9723 return -EINVAL;
9724
7f13657d 9725 return io_uring_create(entries, &p, params);
2b188cc1
JA
9726}
9727
9728SYSCALL_DEFINE2(io_uring_setup, u32, entries,
9729 struct io_uring_params __user *, params)
9730{
9731 return io_uring_setup(entries, params);
9732}
9733
66f4af93
JA
9734static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
9735{
9736 struct io_uring_probe *p;
9737 size_t size;
9738 int i, ret;
9739
9740 size = struct_size(p, ops, nr_args);
9741 if (size == SIZE_MAX)
9742 return -EOVERFLOW;
9743 p = kzalloc(size, GFP_KERNEL);
9744 if (!p)
9745 return -ENOMEM;
9746
9747 ret = -EFAULT;
9748 if (copy_from_user(p, arg, size))
9749 goto out;
9750 ret = -EINVAL;
9751 if (memchr_inv(p, 0, size))
9752 goto out;
9753
9754 p->last_op = IORING_OP_LAST - 1;
9755 if (nr_args > IORING_OP_LAST)
9756 nr_args = IORING_OP_LAST;
9757
9758 for (i = 0; i < nr_args; i++) {
9759 p->ops[i].op = i;
9760 if (!io_op_defs[i].not_supported)
9761 p->ops[i].flags = IO_URING_OP_SUPPORTED;
9762 }
9763 p->ops_len = i;
9764
9765 ret = 0;
9766 if (copy_to_user(arg, p, size))
9767 ret = -EFAULT;
9768out:
9769 kfree(p);
9770 return ret;
9771}
9772
071698e1
JA
9773static int io_register_personality(struct io_ring_ctx *ctx)
9774{
4379bf8b 9775 const struct cred *creds;
61cf9370 9776 u32 id;
1e6fa521 9777 int ret;
071698e1 9778
4379bf8b 9779 creds = get_current_cred();
1e6fa521 9780
61cf9370
MWO
9781 ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
9782 XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
9783 if (!ret)
9784 return id;
9785 put_cred(creds);
1e6fa521 9786 return ret;
071698e1
JA
9787}
9788
21b55dbc
SG
9789static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
9790 unsigned int nr_args)
9791{
9792 struct io_uring_restriction *res;
9793 size_t size;
9794 int i, ret;
9795
7e84e1c7
SG
9796 /* Restrictions allowed only if rings started disabled */
9797 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
9798 return -EBADFD;
9799
21b55dbc 9800 /* We allow only a single restrictions registration */
7e84e1c7 9801 if (ctx->restrictions.registered)
21b55dbc
SG
9802 return -EBUSY;
9803
9804 if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
9805 return -EINVAL;
9806
9807 size = array_size(nr_args, sizeof(*res));
9808 if (size == SIZE_MAX)
9809 return -EOVERFLOW;
9810
9811 res = memdup_user(arg, size);
9812 if (IS_ERR(res))
9813 return PTR_ERR(res);
9814
9815 ret = 0;
9816
9817 for (i = 0; i < nr_args; i++) {
9818 switch (res[i].opcode) {
9819 case IORING_RESTRICTION_REGISTER_OP:
9820 if (res[i].register_op >= IORING_REGISTER_LAST) {
9821 ret = -EINVAL;
9822 goto out;
9823 }
9824
9825 __set_bit(res[i].register_op,
9826 ctx->restrictions.register_op);
9827 break;
9828 case IORING_RESTRICTION_SQE_OP:
9829 if (res[i].sqe_op >= IORING_OP_LAST) {
9830 ret = -EINVAL;
9831 goto out;
9832 }
9833
9834 __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
9835 break;
9836 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
9837 ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
9838 break;
9839 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
9840 ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
9841 break;
9842 default:
9843 ret = -EINVAL;
9844 goto out;
9845 }
9846 }
9847
9848out:
9849 /* Reset all restrictions if an error happened */
9850 if (ret != 0)
9851 memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
9852 else
7e84e1c7 9853 ctx->restrictions.registered = true;
21b55dbc
SG
9854
9855 kfree(res);
9856 return ret;
9857}
9858
7e84e1c7
SG
9859static int io_register_enable_rings(struct io_ring_ctx *ctx)
9860{
9861 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
9862 return -EBADFD;
9863
9864 if (ctx->restrictions.registered)
9865 ctx->restricted = 1;
9866
0298ef96
PB
9867 ctx->flags &= ~IORING_SETUP_R_DISABLED;
9868 if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
9869 wake_up(&ctx->sq_data->wait);
7e84e1c7
SG
9870 return 0;
9871}
9872
071698e1
JA
9873static bool io_register_op_must_quiesce(int op)
9874{
9875 switch (op) {
9876 case IORING_UNREGISTER_FILES:
9877 case IORING_REGISTER_FILES_UPDATE:
9878 case IORING_REGISTER_PROBE:
9879 case IORING_REGISTER_PERSONALITY:
9880 case IORING_UNREGISTER_PERSONALITY:
9881 return false;
9882 default:
9883 return true;
9884 }
9885}
9886
edafccee
JA
9887static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
9888 void __user *arg, unsigned nr_args)
b19062a5
JA
9889 __releases(ctx->uring_lock)
9890 __acquires(ctx->uring_lock)
edafccee
JA
9891{
9892 int ret;
9893
35fa71a0
JA
9894 /*
9895 * We're inside the ring mutex, if the ref is already dying, then
9896 * someone else killed the ctx or is already going through
9897 * io_uring_register().
9898 */
9899 if (percpu_ref_is_dying(&ctx->refs))
9900 return -ENXIO;
9901
071698e1 9902 if (io_register_op_must_quiesce(opcode)) {
05f3fb3c 9903 percpu_ref_kill(&ctx->refs);
b19062a5 9904
05f3fb3c
JA
9905 /*
9906 * Drop uring mutex before waiting for references to exit. If
9907 * another thread is currently inside io_uring_enter() it might
9908 * need to grab the uring_lock to make progress. If we hold it
9909 * here across the drain wait, then we can deadlock. It's safe
9910 * to drop the mutex here, since no new references will come in
9911 * after we've killed the percpu ref.
9912 */
9913 mutex_unlock(&ctx->uring_lock);
af9c1a44
JA
9914 do {
9915 ret = wait_for_completion_interruptible(&ctx->ref_comp);
9916 if (!ret)
9917 break;
ed6930c9
JA
9918 ret = io_run_task_work_sig();
9919 if (ret < 0)
9920 break;
af9c1a44
JA
9921 } while (1);
9922
05f3fb3c 9923 mutex_lock(&ctx->uring_lock);
af9c1a44 9924
c150368b
JA
9925 if (ret) {
9926 percpu_ref_resurrect(&ctx->refs);
21b55dbc
SG
9927 goto out_quiesce;
9928 }
9929 }
9930
9931 if (ctx->restricted) {
9932 if (opcode >= IORING_REGISTER_LAST) {
9933 ret = -EINVAL;
9934 goto out;
9935 }
9936
9937 if (!test_bit(opcode, ctx->restrictions.register_op)) {
9938 ret = -EACCES;
c150368b
JA
9939 goto out;
9940 }
05f3fb3c 9941 }
edafccee
JA
9942
9943 switch (opcode) {
9944 case IORING_REGISTER_BUFFERS:
0a96bbe4 9945 ret = io_sqe_buffers_register(ctx, arg, nr_args);
edafccee
JA
9946 break;
9947 case IORING_UNREGISTER_BUFFERS:
9948 ret = -EINVAL;
9949 if (arg || nr_args)
9950 break;
0a96bbe4 9951 ret = io_sqe_buffers_unregister(ctx);
edafccee 9952 break;
6b06314c
JA
9953 case IORING_REGISTER_FILES:
9954 ret = io_sqe_files_register(ctx, arg, nr_args);
9955 break;
9956 case IORING_UNREGISTER_FILES:
9957 ret = -EINVAL;
9958 if (arg || nr_args)
9959 break;
9960 ret = io_sqe_files_unregister(ctx);
9961 break;
c3a31e60
JA
9962 case IORING_REGISTER_FILES_UPDATE:
9963 ret = io_sqe_files_update(ctx, arg, nr_args);
9964 break;
9b402849 9965 case IORING_REGISTER_EVENTFD:
f2842ab5 9966 case IORING_REGISTER_EVENTFD_ASYNC:
9b402849
JA
9967 ret = -EINVAL;
9968 if (nr_args != 1)
9969 break;
9970 ret = io_eventfd_register(ctx, arg);
f2842ab5
JA
9971 if (ret)
9972 break;
9973 if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
9974 ctx->eventfd_async = 1;
9975 else
9976 ctx->eventfd_async = 0;
9b402849
JA
9977 break;
9978 case IORING_UNREGISTER_EVENTFD:
9979 ret = -EINVAL;
9980 if (arg || nr_args)
9981 break;
9982 ret = io_eventfd_unregister(ctx);
9983 break;
66f4af93
JA
9984 case IORING_REGISTER_PROBE:
9985 ret = -EINVAL;
9986 if (!arg || nr_args > 256)
9987 break;
9988 ret = io_probe(ctx, arg, nr_args);
9989 break;
071698e1
JA
9990 case IORING_REGISTER_PERSONALITY:
9991 ret = -EINVAL;
9992 if (arg || nr_args)
9993 break;
9994 ret = io_register_personality(ctx);
9995 break;
9996 case IORING_UNREGISTER_PERSONALITY:
9997 ret = -EINVAL;
9998 if (arg)
9999 break;
10000 ret = io_unregister_personality(ctx, nr_args);
10001 break;
7e84e1c7
SG
10002 case IORING_REGISTER_ENABLE_RINGS:
10003 ret = -EINVAL;
10004 if (arg || nr_args)
10005 break;
10006 ret = io_register_enable_rings(ctx);
10007 break;
21b55dbc
SG
10008 case IORING_REGISTER_RESTRICTIONS:
10009 ret = io_register_restrictions(ctx, arg, nr_args);
10010 break;
edafccee
JA
10011 default:
10012 ret = -EINVAL;
10013 break;
10014 }
10015
21b55dbc 10016out:
071698e1 10017 if (io_register_op_must_quiesce(opcode)) {
05f3fb3c 10018 /* bring the ctx back to life */
05f3fb3c 10019 percpu_ref_reinit(&ctx->refs);
21b55dbc 10020out_quiesce:
0f158b4c 10021 reinit_completion(&ctx->ref_comp);
05f3fb3c 10022 }
edafccee
JA
10023 return ret;
10024}
10025
10026SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
10027 void __user *, arg, unsigned int, nr_args)
10028{
10029 struct io_ring_ctx *ctx;
10030 long ret = -EBADF;
10031 struct fd f;
10032
10033 f = fdget(fd);
10034 if (!f.file)
10035 return -EBADF;
10036
10037 ret = -EOPNOTSUPP;
10038 if (f.file->f_op != &io_uring_fops)
10039 goto out_fput;
10040
10041 ctx = f.file->private_data;
10042
b6c23dd5
PB
10043 io_run_task_work();
10044
edafccee
JA
10045 mutex_lock(&ctx->uring_lock);
10046 ret = __io_uring_register(ctx, opcode, arg, nr_args);
10047 mutex_unlock(&ctx->uring_lock);
c826bd7a
DD
10048 trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
10049 ctx->cq_ev_fd != NULL, ret);
edafccee
JA
10050out_fput:
10051 fdput(f);
10052 return ret;
10053}
10054
2b188cc1
JA
10055static int __init io_uring_init(void)
10056{
d7f62e82
SM
10057#define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10058 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10059 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10060} while (0)
10061
10062#define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10063 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10064 BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
10065 BUILD_BUG_SQE_ELEM(0, __u8, opcode);
10066 BUILD_BUG_SQE_ELEM(1, __u8, flags);
10067 BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
10068 BUILD_BUG_SQE_ELEM(4, __s32, fd);
10069 BUILD_BUG_SQE_ELEM(8, __u64, off);
10070 BUILD_BUG_SQE_ELEM(8, __u64, addr2);
10071 BUILD_BUG_SQE_ELEM(16, __u64, addr);
7d67af2c 10072 BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
d7f62e82
SM
10073 BUILD_BUG_SQE_ELEM(24, __u32, len);
10074 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
10075 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
10076 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
10077 BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
5769a351
JX
10078 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
10079 BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
d7f62e82
SM
10080 BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
10081 BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
10082 BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
10083 BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
10084 BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
10085 BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
10086 BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
10087 BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
7d67af2c 10088 BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
d7f62e82
SM
10089 BUILD_BUG_SQE_ELEM(32, __u64, user_data);
10090 BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
10091 BUILD_BUG_SQE_ELEM(42, __u16, personality);
7d67af2c 10092 BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
d7f62e82 10093
d3656344 10094 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
84557871 10095 BUILD_BUG_ON(__REQ_F_LAST_BIT >= 8 * sizeof(int));
91f245d5
JA
10096 req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
10097 SLAB_ACCOUNT);
2b188cc1
JA
10098 return 0;
10099};
10100__initcall(io_uring_init);