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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> | |
47 | #include <linux/refcount.h> | |
48 | #include <linux/uio.h> | |
6b47ee6e | 49 | #include <linux/bits.h> |
2b188cc1 JA |
50 | |
51 | #include <linux/sched/signal.h> | |
52 | #include <linux/fs.h> | |
53 | #include <linux/file.h> | |
54 | #include <linux/fdtable.h> | |
55 | #include <linux/mm.h> | |
56 | #include <linux/mman.h> | |
57 | #include <linux/mmu_context.h> | |
58 | #include <linux/percpu.h> | |
59 | #include <linux/slab.h> | |
6c271ce2 | 60 | #include <linux/kthread.h> |
2b188cc1 | 61 | #include <linux/blkdev.h> |
edafccee | 62 | #include <linux/bvec.h> |
2b188cc1 JA |
63 | #include <linux/net.h> |
64 | #include <net/sock.h> | |
65 | #include <net/af_unix.h> | |
6b06314c | 66 | #include <net/scm.h> |
2b188cc1 JA |
67 | #include <linux/anon_inodes.h> |
68 | #include <linux/sched/mm.h> | |
69 | #include <linux/uaccess.h> | |
70 | #include <linux/nospec.h> | |
edafccee JA |
71 | #include <linux/sizes.h> |
72 | #include <linux/hugetlb.h> | |
aa4c3967 | 73 | #include <linux/highmem.h> |
15b71abe JA |
74 | #include <linux/namei.h> |
75 | #include <linux/fsnotify.h> | |
4840e418 | 76 | #include <linux/fadvise.h> |
2b188cc1 | 77 | |
c826bd7a DD |
78 | #define CREATE_TRACE_POINTS |
79 | #include <trace/events/io_uring.h> | |
80 | ||
2b188cc1 JA |
81 | #include <uapi/linux/io_uring.h> |
82 | ||
83 | #include "internal.h" | |
561fb04a | 84 | #include "io-wq.h" |
2b188cc1 | 85 | |
5277deaa | 86 | #define IORING_MAX_ENTRIES 32768 |
33a107f0 | 87 | #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES) |
65e19f54 JA |
88 | |
89 | /* | |
90 | * Shift of 9 is 512 entries, or exactly one page on 64-bit archs | |
91 | */ | |
92 | #define IORING_FILE_TABLE_SHIFT 9 | |
93 | #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT) | |
94 | #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1) | |
95 | #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE) | |
2b188cc1 JA |
96 | |
97 | struct io_uring { | |
98 | u32 head ____cacheline_aligned_in_smp; | |
99 | u32 tail ____cacheline_aligned_in_smp; | |
100 | }; | |
101 | ||
1e84b97b | 102 | /* |
75b28aff HV |
103 | * This data is shared with the application through the mmap at offsets |
104 | * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING. | |
1e84b97b SB |
105 | * |
106 | * The offsets to the member fields are published through struct | |
107 | * io_sqring_offsets when calling io_uring_setup. | |
108 | */ | |
75b28aff | 109 | struct io_rings { |
1e84b97b SB |
110 | /* |
111 | * Head and tail offsets into the ring; the offsets need to be | |
112 | * masked to get valid indices. | |
113 | * | |
75b28aff HV |
114 | * The kernel controls head of the sq ring and the tail of the cq ring, |
115 | * and the application controls tail of the sq ring and the head of the | |
116 | * cq ring. | |
1e84b97b | 117 | */ |
75b28aff | 118 | struct io_uring sq, cq; |
1e84b97b | 119 | /* |
75b28aff | 120 | * Bitmasks to apply to head and tail offsets (constant, equals |
1e84b97b SB |
121 | * ring_entries - 1) |
122 | */ | |
75b28aff HV |
123 | u32 sq_ring_mask, cq_ring_mask; |
124 | /* Ring sizes (constant, power of 2) */ | |
125 | u32 sq_ring_entries, cq_ring_entries; | |
1e84b97b SB |
126 | /* |
127 | * Number of invalid entries dropped by the kernel due to | |
128 | * invalid index stored in array | |
129 | * | |
130 | * Written by the kernel, shouldn't be modified by the | |
131 | * application (i.e. get number of "new events" by comparing to | |
132 | * cached value). | |
133 | * | |
134 | * After a new SQ head value was read by the application this | |
135 | * counter includes all submissions that were dropped reaching | |
136 | * the new SQ head (and possibly more). | |
137 | */ | |
75b28aff | 138 | u32 sq_dropped; |
1e84b97b SB |
139 | /* |
140 | * Runtime flags | |
141 | * | |
142 | * Written by the kernel, shouldn't be modified by the | |
143 | * application. | |
144 | * | |
145 | * The application needs a full memory barrier before checking | |
146 | * for IORING_SQ_NEED_WAKEUP after updating the sq tail. | |
147 | */ | |
75b28aff | 148 | u32 sq_flags; |
1e84b97b SB |
149 | /* |
150 | * Number of completion events lost because the queue was full; | |
151 | * this should be avoided by the application by making sure | |
0b4295b5 | 152 | * there are not more requests pending than there is space in |
1e84b97b SB |
153 | * the completion queue. |
154 | * | |
155 | * Written by the kernel, shouldn't be modified by the | |
156 | * application (i.e. get number of "new events" by comparing to | |
157 | * cached value). | |
158 | * | |
159 | * As completion events come in out of order this counter is not | |
160 | * ordered with any other data. | |
161 | */ | |
75b28aff | 162 | u32 cq_overflow; |
1e84b97b SB |
163 | /* |
164 | * Ring buffer of completion events. | |
165 | * | |
166 | * The kernel writes completion events fresh every time they are | |
167 | * produced, so the application is allowed to modify pending | |
168 | * entries. | |
169 | */ | |
75b28aff | 170 | struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp; |
2b188cc1 JA |
171 | }; |
172 | ||
edafccee JA |
173 | struct io_mapped_ubuf { |
174 | u64 ubuf; | |
175 | size_t len; | |
176 | struct bio_vec *bvec; | |
177 | unsigned int nr_bvecs; | |
178 | }; | |
179 | ||
65e19f54 JA |
180 | struct fixed_file_table { |
181 | struct file **files; | |
31b51510 JA |
182 | }; |
183 | ||
05f3fb3c JA |
184 | enum { |
185 | FFD_F_ATOMIC, | |
186 | }; | |
187 | ||
188 | struct fixed_file_data { | |
189 | struct fixed_file_table *table; | |
190 | struct io_ring_ctx *ctx; | |
191 | ||
192 | struct percpu_ref refs; | |
193 | struct llist_head put_llist; | |
194 | unsigned long state; | |
195 | struct work_struct ref_work; | |
196 | struct completion done; | |
197 | }; | |
198 | ||
2b188cc1 JA |
199 | struct io_ring_ctx { |
200 | struct { | |
201 | struct percpu_ref refs; | |
202 | } ____cacheline_aligned_in_smp; | |
203 | ||
204 | struct { | |
205 | unsigned int flags; | |
69b3e546 JA |
206 | int compat: 1; |
207 | int account_mem: 1; | |
208 | int cq_overflow_flushed: 1; | |
209 | int drain_next: 1; | |
f2842ab5 | 210 | int eventfd_async: 1; |
2b188cc1 | 211 | |
75b28aff HV |
212 | /* |
213 | * Ring buffer of indices into array of io_uring_sqe, which is | |
214 | * mmapped by the application using the IORING_OFF_SQES offset. | |
215 | * | |
216 | * This indirection could e.g. be used to assign fixed | |
217 | * io_uring_sqe entries to operations and only submit them to | |
218 | * the queue when needed. | |
219 | * | |
220 | * The kernel modifies neither the indices array nor the entries | |
221 | * array. | |
222 | */ | |
223 | u32 *sq_array; | |
2b188cc1 JA |
224 | unsigned cached_sq_head; |
225 | unsigned sq_entries; | |
226 | unsigned sq_mask; | |
6c271ce2 | 227 | unsigned sq_thread_idle; |
498ccd9e | 228 | unsigned cached_sq_dropped; |
206aefde | 229 | atomic_t cached_cq_overflow; |
ad3eb2c8 | 230 | unsigned long sq_check_overflow; |
de0617e4 JA |
231 | |
232 | struct list_head defer_list; | |
5262f567 | 233 | struct list_head timeout_list; |
1d7bb1d5 | 234 | struct list_head cq_overflow_list; |
fcb323cc JA |
235 | |
236 | wait_queue_head_t inflight_wait; | |
ad3eb2c8 | 237 | struct io_uring_sqe *sq_sqes; |
2b188cc1 JA |
238 | } ____cacheline_aligned_in_smp; |
239 | ||
206aefde JA |
240 | struct io_rings *rings; |
241 | ||
2b188cc1 | 242 | /* IO offload */ |
561fb04a | 243 | struct io_wq *io_wq; |
6c271ce2 | 244 | struct task_struct *sqo_thread; /* if using sq thread polling */ |
2b188cc1 | 245 | struct mm_struct *sqo_mm; |
6c271ce2 | 246 | wait_queue_head_t sqo_wait; |
75b28aff | 247 | |
6b06314c JA |
248 | /* |
249 | * If used, fixed file set. Writers must ensure that ->refs is dead, | |
250 | * readers must ensure that ->refs is alive as long as the file* is | |
251 | * used. Only updated through io_uring_register(2). | |
252 | */ | |
05f3fb3c | 253 | struct fixed_file_data *file_data; |
6b06314c | 254 | unsigned nr_user_files; |
b14cca0c PB |
255 | int ring_fd; |
256 | struct file *ring_file; | |
6b06314c | 257 | |
edafccee JA |
258 | /* if used, fixed mapped user buffers */ |
259 | unsigned nr_user_bufs; | |
260 | struct io_mapped_ubuf *user_bufs; | |
261 | ||
2b188cc1 JA |
262 | struct user_struct *user; |
263 | ||
0b8c0ec7 | 264 | const struct cred *creds; |
181e448d | 265 | |
206aefde JA |
266 | /* 0 is for ctx quiesce/reinit/free, 1 is for sqo_thread started */ |
267 | struct completion *completions; | |
268 | ||
0ddf92e8 JA |
269 | /* if all else fails... */ |
270 | struct io_kiocb *fallback_req; | |
271 | ||
206aefde JA |
272 | #if defined(CONFIG_UNIX) |
273 | struct socket *ring_sock; | |
274 | #endif | |
275 | ||
276 | struct { | |
277 | unsigned cached_cq_tail; | |
278 | unsigned cq_entries; | |
279 | unsigned cq_mask; | |
280 | atomic_t cq_timeouts; | |
ad3eb2c8 | 281 | unsigned long cq_check_overflow; |
206aefde JA |
282 | struct wait_queue_head cq_wait; |
283 | struct fasync_struct *cq_fasync; | |
284 | struct eventfd_ctx *cq_ev_fd; | |
285 | } ____cacheline_aligned_in_smp; | |
2b188cc1 JA |
286 | |
287 | struct { | |
288 | struct mutex uring_lock; | |
289 | wait_queue_head_t wait; | |
290 | } ____cacheline_aligned_in_smp; | |
291 | ||
292 | struct { | |
293 | spinlock_t completion_lock; | |
e94f141b JA |
294 | struct llist_head poll_llist; |
295 | ||
def596e9 JA |
296 | /* |
297 | * ->poll_list is protected by the ctx->uring_lock for | |
298 | * io_uring instances that don't use IORING_SETUP_SQPOLL. | |
299 | * For SQPOLL, only the single threaded io_sq_thread() will | |
300 | * manipulate the list, hence no extra locking is needed there. | |
301 | */ | |
302 | struct list_head poll_list; | |
78076bb6 JA |
303 | struct hlist_head *cancel_hash; |
304 | unsigned cancel_hash_bits; | |
e94f141b | 305 | bool poll_multi_file; |
31b51510 | 306 | |
fcb323cc JA |
307 | spinlock_t inflight_lock; |
308 | struct list_head inflight_list; | |
2b188cc1 | 309 | } ____cacheline_aligned_in_smp; |
2b188cc1 JA |
310 | }; |
311 | ||
09bb8394 JA |
312 | /* |
313 | * First field must be the file pointer in all the | |
314 | * iocb unions! See also 'struct kiocb' in <linux/fs.h> | |
315 | */ | |
221c5eb2 JA |
316 | struct io_poll_iocb { |
317 | struct file *file; | |
0969e783 JA |
318 | union { |
319 | struct wait_queue_head *head; | |
320 | u64 addr; | |
321 | }; | |
221c5eb2 | 322 | __poll_t events; |
8c838788 | 323 | bool done; |
221c5eb2 | 324 | bool canceled; |
392edb45 | 325 | struct wait_queue_entry wait; |
221c5eb2 JA |
326 | }; |
327 | ||
b5dba59e JA |
328 | struct io_close { |
329 | struct file *file; | |
330 | struct file *put_file; | |
331 | int fd; | |
332 | }; | |
333 | ||
ad8a48ac JA |
334 | struct io_timeout_data { |
335 | struct io_kiocb *req; | |
336 | struct hrtimer timer; | |
337 | struct timespec64 ts; | |
338 | enum hrtimer_mode mode; | |
cc42e0ac | 339 | u32 seq_offset; |
ad8a48ac JA |
340 | }; |
341 | ||
8ed8d3c3 JA |
342 | struct io_accept { |
343 | struct file *file; | |
344 | struct sockaddr __user *addr; | |
345 | int __user *addr_len; | |
346 | int flags; | |
347 | }; | |
348 | ||
349 | struct io_sync { | |
350 | struct file *file; | |
351 | loff_t len; | |
352 | loff_t off; | |
353 | int flags; | |
d63d1b5e | 354 | int mode; |
8ed8d3c3 JA |
355 | }; |
356 | ||
fbf23849 JA |
357 | struct io_cancel { |
358 | struct file *file; | |
359 | u64 addr; | |
360 | }; | |
361 | ||
b29472ee JA |
362 | struct io_timeout { |
363 | struct file *file; | |
364 | u64 addr; | |
365 | int flags; | |
26a61679 | 366 | unsigned count; |
b29472ee JA |
367 | }; |
368 | ||
9adbd45d JA |
369 | struct io_rw { |
370 | /* NOTE: kiocb has the file as the first member, so don't do it here */ | |
371 | struct kiocb kiocb; | |
372 | u64 addr; | |
373 | u64 len; | |
374 | }; | |
375 | ||
3fbb51c1 JA |
376 | struct io_connect { |
377 | struct file *file; | |
378 | struct sockaddr __user *addr; | |
379 | int addr_len; | |
380 | }; | |
381 | ||
e47293fd JA |
382 | struct io_sr_msg { |
383 | struct file *file; | |
fddaface JA |
384 | union { |
385 | struct user_msghdr __user *msg; | |
386 | void __user *buf; | |
387 | }; | |
e47293fd | 388 | int msg_flags; |
fddaface | 389 | size_t len; |
e47293fd JA |
390 | }; |
391 | ||
15b71abe JA |
392 | struct io_open { |
393 | struct file *file; | |
394 | int dfd; | |
eddc7ef5 | 395 | union { |
eddc7ef5 JA |
396 | unsigned mask; |
397 | }; | |
15b71abe | 398 | struct filename *filename; |
eddc7ef5 | 399 | struct statx __user *buffer; |
c12cedf2 | 400 | struct open_how how; |
15b71abe JA |
401 | }; |
402 | ||
05f3fb3c JA |
403 | struct io_files_update { |
404 | struct file *file; | |
405 | u64 arg; | |
406 | u32 nr_args; | |
407 | u32 offset; | |
408 | }; | |
409 | ||
4840e418 JA |
410 | struct io_fadvise { |
411 | struct file *file; | |
412 | u64 offset; | |
413 | u32 len; | |
414 | u32 advice; | |
415 | }; | |
416 | ||
c1ca757b JA |
417 | struct io_madvise { |
418 | struct file *file; | |
419 | u64 addr; | |
420 | u32 len; | |
421 | u32 advice; | |
422 | }; | |
423 | ||
f499a021 JA |
424 | struct io_async_connect { |
425 | struct sockaddr_storage address; | |
426 | }; | |
427 | ||
03b1230c JA |
428 | struct io_async_msghdr { |
429 | struct iovec fast_iov[UIO_FASTIOV]; | |
430 | struct iovec *iov; | |
431 | struct sockaddr __user *uaddr; | |
432 | struct msghdr msg; | |
433 | }; | |
434 | ||
f67676d1 JA |
435 | struct io_async_rw { |
436 | struct iovec fast_iov[UIO_FASTIOV]; | |
437 | struct iovec *iov; | |
438 | ssize_t nr_segs; | |
439 | ssize_t size; | |
440 | }; | |
441 | ||
15b71abe JA |
442 | struct io_async_open { |
443 | struct filename *filename; | |
444 | }; | |
445 | ||
1a6b74fc | 446 | struct io_async_ctx { |
f67676d1 JA |
447 | union { |
448 | struct io_async_rw rw; | |
03b1230c | 449 | struct io_async_msghdr msg; |
f499a021 | 450 | struct io_async_connect connect; |
2d28390a | 451 | struct io_timeout_data timeout; |
15b71abe | 452 | struct io_async_open open; |
f67676d1 | 453 | }; |
1a6b74fc JA |
454 | }; |
455 | ||
6b47ee6e PB |
456 | enum { |
457 | REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT, | |
458 | REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT, | |
459 | REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT, | |
460 | REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT, | |
461 | REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT, | |
462 | ||
463 | REQ_F_LINK_NEXT_BIT, | |
464 | REQ_F_FAIL_LINK_BIT, | |
465 | REQ_F_INFLIGHT_BIT, | |
466 | REQ_F_CUR_POS_BIT, | |
467 | REQ_F_NOWAIT_BIT, | |
468 | REQ_F_IOPOLL_COMPLETED_BIT, | |
469 | REQ_F_LINK_TIMEOUT_BIT, | |
470 | REQ_F_TIMEOUT_BIT, | |
471 | REQ_F_ISREG_BIT, | |
472 | REQ_F_MUST_PUNT_BIT, | |
473 | REQ_F_TIMEOUT_NOSEQ_BIT, | |
474 | REQ_F_COMP_LOCKED_BIT, | |
475 | }; | |
476 | ||
477 | enum { | |
478 | /* ctx owns file */ | |
479 | REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT), | |
480 | /* drain existing IO first */ | |
481 | REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT), | |
482 | /* linked sqes */ | |
483 | REQ_F_LINK = BIT(REQ_F_LINK_BIT), | |
484 | /* doesn't sever on completion < 0 */ | |
485 | REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT), | |
486 | /* IOSQE_ASYNC */ | |
487 | REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT), | |
488 | ||
489 | /* already grabbed next link */ | |
490 | REQ_F_LINK_NEXT = BIT(REQ_F_LINK_NEXT_BIT), | |
491 | /* fail rest of links */ | |
492 | REQ_F_FAIL_LINK = BIT(REQ_F_FAIL_LINK_BIT), | |
493 | /* on inflight list */ | |
494 | REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT), | |
495 | /* read/write uses file position */ | |
496 | REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT), | |
497 | /* must not punt to workers */ | |
498 | REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT), | |
499 | /* polled IO has completed */ | |
500 | REQ_F_IOPOLL_COMPLETED = BIT(REQ_F_IOPOLL_COMPLETED_BIT), | |
501 | /* has linked timeout */ | |
502 | REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT), | |
503 | /* timeout request */ | |
504 | REQ_F_TIMEOUT = BIT(REQ_F_TIMEOUT_BIT), | |
505 | /* regular file */ | |
506 | REQ_F_ISREG = BIT(REQ_F_ISREG_BIT), | |
507 | /* must be punted even for NONBLOCK */ | |
508 | REQ_F_MUST_PUNT = BIT(REQ_F_MUST_PUNT_BIT), | |
509 | /* no timeout sequence */ | |
510 | REQ_F_TIMEOUT_NOSEQ = BIT(REQ_F_TIMEOUT_NOSEQ_BIT), | |
511 | /* completion under lock */ | |
512 | REQ_F_COMP_LOCKED = BIT(REQ_F_COMP_LOCKED_BIT), | |
513 | }; | |
514 | ||
09bb8394 JA |
515 | /* |
516 | * NOTE! Each of the iocb union members has the file pointer | |
517 | * as the first entry in their struct definition. So you can | |
518 | * access the file pointer through any of the sub-structs, | |
519 | * or directly as just 'ki_filp' in this struct. | |
520 | */ | |
2b188cc1 | 521 | struct io_kiocb { |
221c5eb2 | 522 | union { |
09bb8394 | 523 | struct file *file; |
9adbd45d | 524 | struct io_rw rw; |
221c5eb2 | 525 | struct io_poll_iocb poll; |
8ed8d3c3 JA |
526 | struct io_accept accept; |
527 | struct io_sync sync; | |
fbf23849 | 528 | struct io_cancel cancel; |
b29472ee | 529 | struct io_timeout timeout; |
3fbb51c1 | 530 | struct io_connect connect; |
e47293fd | 531 | struct io_sr_msg sr_msg; |
15b71abe | 532 | struct io_open open; |
b5dba59e | 533 | struct io_close close; |
05f3fb3c | 534 | struct io_files_update files_update; |
4840e418 | 535 | struct io_fadvise fadvise; |
c1ca757b | 536 | struct io_madvise madvise; |
221c5eb2 | 537 | }; |
2b188cc1 | 538 | |
1a6b74fc | 539 | struct io_async_ctx *io; |
b14cca0c PB |
540 | /* |
541 | * llist_node is only used for poll deferred completions | |
542 | */ | |
543 | struct llist_node llist_node; | |
cf6fd4bd PB |
544 | bool has_user; |
545 | bool in_async; | |
546 | bool needs_fixed_file; | |
d625c6ee | 547 | u8 opcode; |
2b188cc1 JA |
548 | |
549 | struct io_ring_ctx *ctx; | |
eac406c6 JA |
550 | union { |
551 | struct list_head list; | |
78076bb6 | 552 | struct hlist_node hash_node; |
eac406c6 | 553 | }; |
9e645e11 | 554 | struct list_head link_list; |
2b188cc1 | 555 | unsigned int flags; |
c16361c1 | 556 | refcount_t refs; |
2b188cc1 | 557 | u64 user_data; |
9e645e11 | 558 | u32 result; |
de0617e4 | 559 | u32 sequence; |
2b188cc1 | 560 | |
fcb323cc JA |
561 | struct list_head inflight_entry; |
562 | ||
561fb04a | 563 | struct io_wq_work work; |
2b188cc1 JA |
564 | }; |
565 | ||
566 | #define IO_PLUG_THRESHOLD 2 | |
def596e9 | 567 | #define IO_IOPOLL_BATCH 8 |
2b188cc1 | 568 | |
9a56a232 JA |
569 | struct io_submit_state { |
570 | struct blk_plug plug; | |
571 | ||
2579f913 JA |
572 | /* |
573 | * io_kiocb alloc cache | |
574 | */ | |
575 | void *reqs[IO_IOPOLL_BATCH]; | |
576 | unsigned int free_reqs; | |
577 | unsigned int cur_req; | |
578 | ||
9a56a232 JA |
579 | /* |
580 | * File reference cache | |
581 | */ | |
582 | struct file *file; | |
583 | unsigned int fd; | |
584 | unsigned int has_refs; | |
585 | unsigned int used_refs; | |
586 | unsigned int ios_left; | |
587 | }; | |
588 | ||
d3656344 JA |
589 | struct io_op_def { |
590 | /* needs req->io allocated for deferral/async */ | |
591 | unsigned async_ctx : 1; | |
592 | /* needs current->mm setup, does mm access */ | |
593 | unsigned needs_mm : 1; | |
594 | /* needs req->file assigned */ | |
595 | unsigned needs_file : 1; | |
596 | /* needs req->file assigned IFF fd is >= 0 */ | |
597 | unsigned fd_non_neg : 1; | |
598 | /* hash wq insertion if file is a regular file */ | |
599 | unsigned hash_reg_file : 1; | |
600 | /* unbound wq insertion if file is a non-regular file */ | |
601 | unsigned unbound_nonreg_file : 1; | |
66f4af93 JA |
602 | /* opcode is not supported by this kernel */ |
603 | unsigned not_supported : 1; | |
d3656344 JA |
604 | }; |
605 | ||
606 | static const struct io_op_def io_op_defs[] = { | |
607 | { | |
608 | /* IORING_OP_NOP */ | |
609 | }, | |
610 | { | |
611 | /* IORING_OP_READV */ | |
612 | .async_ctx = 1, | |
613 | .needs_mm = 1, | |
614 | .needs_file = 1, | |
615 | .unbound_nonreg_file = 1, | |
616 | }, | |
617 | { | |
618 | /* IORING_OP_WRITEV */ | |
619 | .async_ctx = 1, | |
620 | .needs_mm = 1, | |
621 | .needs_file = 1, | |
622 | .hash_reg_file = 1, | |
623 | .unbound_nonreg_file = 1, | |
624 | }, | |
625 | { | |
626 | /* IORING_OP_FSYNC */ | |
627 | .needs_file = 1, | |
628 | }, | |
629 | { | |
630 | /* IORING_OP_READ_FIXED */ | |
631 | .needs_file = 1, | |
632 | .unbound_nonreg_file = 1, | |
633 | }, | |
634 | { | |
635 | /* IORING_OP_WRITE_FIXED */ | |
636 | .needs_file = 1, | |
637 | .hash_reg_file = 1, | |
638 | .unbound_nonreg_file = 1, | |
639 | }, | |
640 | { | |
641 | /* IORING_OP_POLL_ADD */ | |
642 | .needs_file = 1, | |
643 | .unbound_nonreg_file = 1, | |
644 | }, | |
645 | { | |
646 | /* IORING_OP_POLL_REMOVE */ | |
647 | }, | |
648 | { | |
649 | /* IORING_OP_SYNC_FILE_RANGE */ | |
650 | .needs_file = 1, | |
651 | }, | |
652 | { | |
653 | /* IORING_OP_SENDMSG */ | |
654 | .async_ctx = 1, | |
655 | .needs_mm = 1, | |
656 | .needs_file = 1, | |
657 | .unbound_nonreg_file = 1, | |
658 | }, | |
659 | { | |
660 | /* IORING_OP_RECVMSG */ | |
661 | .async_ctx = 1, | |
662 | .needs_mm = 1, | |
663 | .needs_file = 1, | |
664 | .unbound_nonreg_file = 1, | |
665 | }, | |
666 | { | |
667 | /* IORING_OP_TIMEOUT */ | |
668 | .async_ctx = 1, | |
669 | .needs_mm = 1, | |
670 | }, | |
671 | { | |
672 | /* IORING_OP_TIMEOUT_REMOVE */ | |
673 | }, | |
674 | { | |
675 | /* IORING_OP_ACCEPT */ | |
676 | .needs_mm = 1, | |
677 | .needs_file = 1, | |
678 | .unbound_nonreg_file = 1, | |
679 | }, | |
680 | { | |
681 | /* IORING_OP_ASYNC_CANCEL */ | |
682 | }, | |
683 | { | |
684 | /* IORING_OP_LINK_TIMEOUT */ | |
685 | .async_ctx = 1, | |
686 | .needs_mm = 1, | |
687 | }, | |
688 | { | |
689 | /* IORING_OP_CONNECT */ | |
690 | .async_ctx = 1, | |
691 | .needs_mm = 1, | |
692 | .needs_file = 1, | |
693 | .unbound_nonreg_file = 1, | |
694 | }, | |
695 | { | |
696 | /* IORING_OP_FALLOCATE */ | |
697 | .needs_file = 1, | |
698 | }, | |
699 | { | |
700 | /* IORING_OP_OPENAT */ | |
701 | .needs_file = 1, | |
702 | .fd_non_neg = 1, | |
703 | }, | |
704 | { | |
705 | /* IORING_OP_CLOSE */ | |
706 | .needs_file = 1, | |
707 | }, | |
708 | { | |
709 | /* IORING_OP_FILES_UPDATE */ | |
710 | .needs_mm = 1, | |
711 | }, | |
712 | { | |
713 | /* IORING_OP_STATX */ | |
714 | .needs_mm = 1, | |
715 | .needs_file = 1, | |
716 | .fd_non_neg = 1, | |
717 | }, | |
3a6820f2 JA |
718 | { |
719 | /* IORING_OP_READ */ | |
720 | .needs_mm = 1, | |
721 | .needs_file = 1, | |
722 | .unbound_nonreg_file = 1, | |
723 | }, | |
724 | { | |
725 | /* IORING_OP_WRITE */ | |
726 | .needs_mm = 1, | |
727 | .needs_file = 1, | |
728 | .unbound_nonreg_file = 1, | |
729 | }, | |
4840e418 JA |
730 | { |
731 | /* IORING_OP_FADVISE */ | |
732 | .needs_file = 1, | |
733 | }, | |
c1ca757b JA |
734 | { |
735 | /* IORING_OP_MADVISE */ | |
736 | .needs_mm = 1, | |
737 | }, | |
fddaface JA |
738 | { |
739 | /* IORING_OP_SEND */ | |
740 | .needs_mm = 1, | |
741 | .needs_file = 1, | |
742 | .unbound_nonreg_file = 1, | |
743 | }, | |
744 | { | |
745 | /* IORING_OP_RECV */ | |
746 | .needs_mm = 1, | |
747 | .needs_file = 1, | |
748 | .unbound_nonreg_file = 1, | |
749 | }, | |
cebdb986 JA |
750 | { |
751 | /* IORING_OP_OPENAT2 */ | |
752 | .needs_file = 1, | |
753 | .fd_non_neg = 1, | |
754 | }, | |
d3656344 JA |
755 | }; |
756 | ||
561fb04a | 757 | static void io_wq_submit_work(struct io_wq_work **workptr); |
78e19bbe | 758 | static void io_cqring_fill_event(struct io_kiocb *req, long res); |
ec9c02ad | 759 | static void io_put_req(struct io_kiocb *req); |
978db57e | 760 | static void __io_double_put_req(struct io_kiocb *req); |
94ae5e77 JA |
761 | static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req); |
762 | static void io_queue_linked_timeout(struct io_kiocb *req); | |
05f3fb3c JA |
763 | static int __io_sqe_files_update(struct io_ring_ctx *ctx, |
764 | struct io_uring_files_update *ip, | |
765 | unsigned nr_args); | |
de0617e4 | 766 | |
2b188cc1 JA |
767 | static struct kmem_cache *req_cachep; |
768 | ||
769 | static const struct file_operations io_uring_fops; | |
770 | ||
771 | struct sock *io_uring_get_socket(struct file *file) | |
772 | { | |
773 | #if defined(CONFIG_UNIX) | |
774 | if (file->f_op == &io_uring_fops) { | |
775 | struct io_ring_ctx *ctx = file->private_data; | |
776 | ||
777 | return ctx->ring_sock->sk; | |
778 | } | |
779 | #endif | |
780 | return NULL; | |
781 | } | |
782 | EXPORT_SYMBOL(io_uring_get_socket); | |
783 | ||
784 | static void io_ring_ctx_ref_free(struct percpu_ref *ref) | |
785 | { | |
786 | struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs); | |
787 | ||
206aefde | 788 | complete(&ctx->completions[0]); |
2b188cc1 JA |
789 | } |
790 | ||
791 | static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) | |
792 | { | |
793 | struct io_ring_ctx *ctx; | |
78076bb6 | 794 | int hash_bits; |
2b188cc1 JA |
795 | |
796 | ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); | |
797 | if (!ctx) | |
798 | return NULL; | |
799 | ||
0ddf92e8 JA |
800 | ctx->fallback_req = kmem_cache_alloc(req_cachep, GFP_KERNEL); |
801 | if (!ctx->fallback_req) | |
802 | goto err; | |
803 | ||
206aefde JA |
804 | ctx->completions = kmalloc(2 * sizeof(struct completion), GFP_KERNEL); |
805 | if (!ctx->completions) | |
806 | goto err; | |
807 | ||
78076bb6 JA |
808 | /* |
809 | * Use 5 bits less than the max cq entries, that should give us around | |
810 | * 32 entries per hash list if totally full and uniformly spread. | |
811 | */ | |
812 | hash_bits = ilog2(p->cq_entries); | |
813 | hash_bits -= 5; | |
814 | if (hash_bits <= 0) | |
815 | hash_bits = 1; | |
816 | ctx->cancel_hash_bits = hash_bits; | |
817 | ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head), | |
818 | GFP_KERNEL); | |
819 | if (!ctx->cancel_hash) | |
820 | goto err; | |
821 | __hash_init(ctx->cancel_hash, 1U << hash_bits); | |
822 | ||
21482896 | 823 | if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free, |
206aefde JA |
824 | PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) |
825 | goto err; | |
2b188cc1 JA |
826 | |
827 | ctx->flags = p->flags; | |
828 | init_waitqueue_head(&ctx->cq_wait); | |
1d7bb1d5 | 829 | INIT_LIST_HEAD(&ctx->cq_overflow_list); |
206aefde JA |
830 | init_completion(&ctx->completions[0]); |
831 | init_completion(&ctx->completions[1]); | |
2b188cc1 JA |
832 | mutex_init(&ctx->uring_lock); |
833 | init_waitqueue_head(&ctx->wait); | |
834 | spin_lock_init(&ctx->completion_lock); | |
e94f141b | 835 | init_llist_head(&ctx->poll_llist); |
def596e9 | 836 | INIT_LIST_HEAD(&ctx->poll_list); |
de0617e4 | 837 | INIT_LIST_HEAD(&ctx->defer_list); |
5262f567 | 838 | INIT_LIST_HEAD(&ctx->timeout_list); |
fcb323cc JA |
839 | init_waitqueue_head(&ctx->inflight_wait); |
840 | spin_lock_init(&ctx->inflight_lock); | |
841 | INIT_LIST_HEAD(&ctx->inflight_list); | |
2b188cc1 | 842 | return ctx; |
206aefde | 843 | err: |
0ddf92e8 JA |
844 | if (ctx->fallback_req) |
845 | kmem_cache_free(req_cachep, ctx->fallback_req); | |
206aefde | 846 | kfree(ctx->completions); |
78076bb6 | 847 | kfree(ctx->cancel_hash); |
206aefde JA |
848 | kfree(ctx); |
849 | return NULL; | |
2b188cc1 JA |
850 | } |
851 | ||
9d858b21 | 852 | static inline bool __req_need_defer(struct io_kiocb *req) |
7adf4eaf | 853 | { |
a197f664 JL |
854 | struct io_ring_ctx *ctx = req->ctx; |
855 | ||
498ccd9e JA |
856 | return req->sequence != ctx->cached_cq_tail + ctx->cached_sq_dropped |
857 | + atomic_read(&ctx->cached_cq_overflow); | |
7adf4eaf JA |
858 | } |
859 | ||
9d858b21 | 860 | static inline bool req_need_defer(struct io_kiocb *req) |
de0617e4 | 861 | { |
87987898 | 862 | if (unlikely(req->flags & REQ_F_IO_DRAIN)) |
9d858b21 | 863 | return __req_need_defer(req); |
de0617e4 | 864 | |
9d858b21 | 865 | return false; |
de0617e4 JA |
866 | } |
867 | ||
7adf4eaf | 868 | static struct io_kiocb *io_get_deferred_req(struct io_ring_ctx *ctx) |
de0617e4 JA |
869 | { |
870 | struct io_kiocb *req; | |
871 | ||
7adf4eaf | 872 | req = list_first_entry_or_null(&ctx->defer_list, struct io_kiocb, list); |
9d858b21 | 873 | if (req && !req_need_defer(req)) { |
de0617e4 JA |
874 | list_del_init(&req->list); |
875 | return req; | |
876 | } | |
877 | ||
878 | return NULL; | |
879 | } | |
880 | ||
5262f567 JA |
881 | static struct io_kiocb *io_get_timeout_req(struct io_ring_ctx *ctx) |
882 | { | |
7adf4eaf JA |
883 | struct io_kiocb *req; |
884 | ||
885 | req = list_first_entry_or_null(&ctx->timeout_list, struct io_kiocb, list); | |
93bd25bb JA |
886 | if (req) { |
887 | if (req->flags & REQ_F_TIMEOUT_NOSEQ) | |
888 | return NULL; | |
fb4b3d3f | 889 | if (!__req_need_defer(req)) { |
93bd25bb JA |
890 | list_del_init(&req->list); |
891 | return req; | |
892 | } | |
7adf4eaf JA |
893 | } |
894 | ||
895 | return NULL; | |
5262f567 JA |
896 | } |
897 | ||
de0617e4 | 898 | static void __io_commit_cqring(struct io_ring_ctx *ctx) |
2b188cc1 | 899 | { |
75b28aff | 900 | struct io_rings *rings = ctx->rings; |
2b188cc1 | 901 | |
07910158 PB |
902 | /* order cqe stores with ring update */ |
903 | smp_store_release(&rings->cq.tail, ctx->cached_cq_tail); | |
2b188cc1 | 904 | |
07910158 PB |
905 | if (wq_has_sleeper(&ctx->cq_wait)) { |
906 | wake_up_interruptible(&ctx->cq_wait); | |
907 | kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN); | |
2b188cc1 JA |
908 | } |
909 | } | |
910 | ||
94ae5e77 JA |
911 | static inline bool io_prep_async_work(struct io_kiocb *req, |
912 | struct io_kiocb **link) | |
18d9be1a | 913 | { |
d3656344 | 914 | const struct io_op_def *def = &io_op_defs[req->opcode]; |
561fb04a | 915 | bool do_hashed = false; |
54a91f3b | 916 | |
d3656344 JA |
917 | if (req->flags & REQ_F_ISREG) { |
918 | if (def->hash_reg_file) | |
3529d8c2 | 919 | do_hashed = true; |
d3656344 JA |
920 | } else { |
921 | if (def->unbound_nonreg_file) | |
3529d8c2 | 922 | req->work.flags |= IO_WQ_WORK_UNBOUND; |
54a91f3b | 923 | } |
d3656344 | 924 | if (def->needs_mm) |
3529d8c2 | 925 | req->work.flags |= IO_WQ_WORK_NEEDS_USER; |
54a91f3b | 926 | |
94ae5e77 | 927 | *link = io_prep_linked_timeout(req); |
561fb04a JA |
928 | return do_hashed; |
929 | } | |
930 | ||
a197f664 | 931 | static inline void io_queue_async_work(struct io_kiocb *req) |
561fb04a | 932 | { |
a197f664 | 933 | struct io_ring_ctx *ctx = req->ctx; |
94ae5e77 JA |
934 | struct io_kiocb *link; |
935 | bool do_hashed; | |
936 | ||
937 | do_hashed = io_prep_async_work(req, &link); | |
561fb04a JA |
938 | |
939 | trace_io_uring_queue_async_work(ctx, do_hashed, req, &req->work, | |
940 | req->flags); | |
941 | if (!do_hashed) { | |
942 | io_wq_enqueue(ctx->io_wq, &req->work); | |
943 | } else { | |
944 | io_wq_enqueue_hashed(ctx->io_wq, &req->work, | |
945 | file_inode(req->file)); | |
946 | } | |
94ae5e77 JA |
947 | |
948 | if (link) | |
949 | io_queue_linked_timeout(link); | |
18d9be1a JA |
950 | } |
951 | ||
5262f567 JA |
952 | static void io_kill_timeout(struct io_kiocb *req) |
953 | { | |
954 | int ret; | |
955 | ||
2d28390a | 956 | ret = hrtimer_try_to_cancel(&req->io->timeout.timer); |
5262f567 JA |
957 | if (ret != -1) { |
958 | atomic_inc(&req->ctx->cq_timeouts); | |
842f9612 | 959 | list_del_init(&req->list); |
78e19bbe | 960 | io_cqring_fill_event(req, 0); |
ec9c02ad | 961 | io_put_req(req); |
5262f567 JA |
962 | } |
963 | } | |
964 | ||
965 | static void io_kill_timeouts(struct io_ring_ctx *ctx) | |
966 | { | |
967 | struct io_kiocb *req, *tmp; | |
968 | ||
969 | spin_lock_irq(&ctx->completion_lock); | |
970 | list_for_each_entry_safe(req, tmp, &ctx->timeout_list, list) | |
971 | io_kill_timeout(req); | |
972 | spin_unlock_irq(&ctx->completion_lock); | |
973 | } | |
974 | ||
de0617e4 JA |
975 | static void io_commit_cqring(struct io_ring_ctx *ctx) |
976 | { | |
977 | struct io_kiocb *req; | |
978 | ||
5262f567 JA |
979 | while ((req = io_get_timeout_req(ctx)) != NULL) |
980 | io_kill_timeout(req); | |
981 | ||
de0617e4 JA |
982 | __io_commit_cqring(ctx); |
983 | ||
87987898 | 984 | while ((req = io_get_deferred_req(ctx)) != NULL) |
a197f664 | 985 | io_queue_async_work(req); |
de0617e4 JA |
986 | } |
987 | ||
2b188cc1 JA |
988 | static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx) |
989 | { | |
75b28aff | 990 | struct io_rings *rings = ctx->rings; |
2b188cc1 JA |
991 | unsigned tail; |
992 | ||
993 | tail = ctx->cached_cq_tail; | |
115e12e5 SB |
994 | /* |
995 | * writes to the cq entry need to come after reading head; the | |
996 | * control dependency is enough as we're using WRITE_ONCE to | |
997 | * fill the cq entry | |
998 | */ | |
75b28aff | 999 | if (tail - READ_ONCE(rings->cq.head) == rings->cq_ring_entries) |
2b188cc1 JA |
1000 | return NULL; |
1001 | ||
1002 | ctx->cached_cq_tail++; | |
75b28aff | 1003 | return &rings->cqes[tail & ctx->cq_mask]; |
2b188cc1 JA |
1004 | } |
1005 | ||
f2842ab5 JA |
1006 | static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx) |
1007 | { | |
1008 | if (!ctx->eventfd_async) | |
1009 | return true; | |
1010 | return io_wq_current_is_worker() || in_interrupt(); | |
1011 | } | |
1012 | ||
1d7bb1d5 JA |
1013 | static void io_cqring_ev_posted(struct io_ring_ctx *ctx) |
1014 | { | |
1015 | if (waitqueue_active(&ctx->wait)) | |
1016 | wake_up(&ctx->wait); | |
1017 | if (waitqueue_active(&ctx->sqo_wait)) | |
1018 | wake_up(&ctx->sqo_wait); | |
f2842ab5 | 1019 | if (ctx->cq_ev_fd && io_should_trigger_evfd(ctx)) |
1d7bb1d5 JA |
1020 | eventfd_signal(ctx->cq_ev_fd, 1); |
1021 | } | |
1022 | ||
c4a2ed72 JA |
1023 | /* Returns true if there are no backlogged entries after the flush */ |
1024 | static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) | |
1d7bb1d5 JA |
1025 | { |
1026 | struct io_rings *rings = ctx->rings; | |
1027 | struct io_uring_cqe *cqe; | |
1028 | struct io_kiocb *req; | |
1029 | unsigned long flags; | |
1030 | LIST_HEAD(list); | |
1031 | ||
1032 | if (!force) { | |
1033 | if (list_empty_careful(&ctx->cq_overflow_list)) | |
c4a2ed72 | 1034 | return true; |
1d7bb1d5 JA |
1035 | if ((ctx->cached_cq_tail - READ_ONCE(rings->cq.head) == |
1036 | rings->cq_ring_entries)) | |
c4a2ed72 | 1037 | return false; |
1d7bb1d5 JA |
1038 | } |
1039 | ||
1040 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
1041 | ||
1042 | /* if force is set, the ring is going away. always drop after that */ | |
1043 | if (force) | |
69b3e546 | 1044 | ctx->cq_overflow_flushed = 1; |
1d7bb1d5 | 1045 | |
c4a2ed72 | 1046 | cqe = NULL; |
1d7bb1d5 JA |
1047 | while (!list_empty(&ctx->cq_overflow_list)) { |
1048 | cqe = io_get_cqring(ctx); | |
1049 | if (!cqe && !force) | |
1050 | break; | |
1051 | ||
1052 | req = list_first_entry(&ctx->cq_overflow_list, struct io_kiocb, | |
1053 | list); | |
1054 | list_move(&req->list, &list); | |
1055 | if (cqe) { | |
1056 | WRITE_ONCE(cqe->user_data, req->user_data); | |
1057 | WRITE_ONCE(cqe->res, req->result); | |
1058 | WRITE_ONCE(cqe->flags, 0); | |
1059 | } else { | |
1060 | WRITE_ONCE(ctx->rings->cq_overflow, | |
1061 | atomic_inc_return(&ctx->cached_cq_overflow)); | |
1062 | } | |
1063 | } | |
1064 | ||
1065 | io_commit_cqring(ctx); | |
ad3eb2c8 JA |
1066 | if (cqe) { |
1067 | clear_bit(0, &ctx->sq_check_overflow); | |
1068 | clear_bit(0, &ctx->cq_check_overflow); | |
1069 | } | |
1d7bb1d5 JA |
1070 | spin_unlock_irqrestore(&ctx->completion_lock, flags); |
1071 | io_cqring_ev_posted(ctx); | |
1072 | ||
1073 | while (!list_empty(&list)) { | |
1074 | req = list_first_entry(&list, struct io_kiocb, list); | |
1075 | list_del(&req->list); | |
ec9c02ad | 1076 | io_put_req(req); |
1d7bb1d5 | 1077 | } |
c4a2ed72 JA |
1078 | |
1079 | return cqe != NULL; | |
1d7bb1d5 JA |
1080 | } |
1081 | ||
78e19bbe | 1082 | static void io_cqring_fill_event(struct io_kiocb *req, long res) |
2b188cc1 | 1083 | { |
78e19bbe | 1084 | struct io_ring_ctx *ctx = req->ctx; |
2b188cc1 JA |
1085 | struct io_uring_cqe *cqe; |
1086 | ||
78e19bbe | 1087 | trace_io_uring_complete(ctx, req->user_data, res); |
51c3ff62 | 1088 | |
2b188cc1 JA |
1089 | /* |
1090 | * If we can't get a cq entry, userspace overflowed the | |
1091 | * submission (by quite a lot). Increment the overflow count in | |
1092 | * the ring. | |
1093 | */ | |
1094 | cqe = io_get_cqring(ctx); | |
1d7bb1d5 | 1095 | if (likely(cqe)) { |
78e19bbe | 1096 | WRITE_ONCE(cqe->user_data, req->user_data); |
2b188cc1 | 1097 | WRITE_ONCE(cqe->res, res); |
c71ffb67 | 1098 | WRITE_ONCE(cqe->flags, 0); |
1d7bb1d5 | 1099 | } else if (ctx->cq_overflow_flushed) { |
498ccd9e JA |
1100 | WRITE_ONCE(ctx->rings->cq_overflow, |
1101 | atomic_inc_return(&ctx->cached_cq_overflow)); | |
1d7bb1d5 | 1102 | } else { |
ad3eb2c8 JA |
1103 | if (list_empty(&ctx->cq_overflow_list)) { |
1104 | set_bit(0, &ctx->sq_check_overflow); | |
1105 | set_bit(0, &ctx->cq_check_overflow); | |
1106 | } | |
1d7bb1d5 JA |
1107 | refcount_inc(&req->refs); |
1108 | req->result = res; | |
1109 | list_add_tail(&req->list, &ctx->cq_overflow_list); | |
2b188cc1 JA |
1110 | } |
1111 | } | |
1112 | ||
78e19bbe | 1113 | static void io_cqring_add_event(struct io_kiocb *req, long res) |
2b188cc1 | 1114 | { |
78e19bbe | 1115 | struct io_ring_ctx *ctx = req->ctx; |
2b188cc1 JA |
1116 | unsigned long flags; |
1117 | ||
1118 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
78e19bbe | 1119 | io_cqring_fill_event(req, res); |
2b188cc1 JA |
1120 | io_commit_cqring(ctx); |
1121 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
1122 | ||
8c838788 | 1123 | io_cqring_ev_posted(ctx); |
2b188cc1 JA |
1124 | } |
1125 | ||
0ddf92e8 JA |
1126 | static inline bool io_is_fallback_req(struct io_kiocb *req) |
1127 | { | |
1128 | return req == (struct io_kiocb *) | |
1129 | ((unsigned long) req->ctx->fallback_req & ~1UL); | |
1130 | } | |
1131 | ||
1132 | static struct io_kiocb *io_get_fallback_req(struct io_ring_ctx *ctx) | |
1133 | { | |
1134 | struct io_kiocb *req; | |
1135 | ||
1136 | req = ctx->fallback_req; | |
1137 | if (!test_and_set_bit_lock(0, (unsigned long *) ctx->fallback_req)) | |
1138 | return req; | |
1139 | ||
1140 | return NULL; | |
1141 | } | |
1142 | ||
2579f913 JA |
1143 | static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx, |
1144 | struct io_submit_state *state) | |
2b188cc1 | 1145 | { |
fd6fab2c | 1146 | gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; |
2b188cc1 JA |
1147 | struct io_kiocb *req; |
1148 | ||
2579f913 | 1149 | if (!state) { |
fd6fab2c | 1150 | req = kmem_cache_alloc(req_cachep, gfp); |
2579f913 | 1151 | if (unlikely(!req)) |
0ddf92e8 | 1152 | goto fallback; |
2579f913 JA |
1153 | } else if (!state->free_reqs) { |
1154 | size_t sz; | |
1155 | int ret; | |
1156 | ||
1157 | sz = min_t(size_t, state->ios_left, ARRAY_SIZE(state->reqs)); | |
fd6fab2c JA |
1158 | ret = kmem_cache_alloc_bulk(req_cachep, gfp, sz, state->reqs); |
1159 | ||
1160 | /* | |
1161 | * Bulk alloc is all-or-nothing. If we fail to get a batch, | |
1162 | * retry single alloc to be on the safe side. | |
1163 | */ | |
1164 | if (unlikely(ret <= 0)) { | |
1165 | state->reqs[0] = kmem_cache_alloc(req_cachep, gfp); | |
1166 | if (!state->reqs[0]) | |
0ddf92e8 | 1167 | goto fallback; |
fd6fab2c JA |
1168 | ret = 1; |
1169 | } | |
2579f913 JA |
1170 | state->free_reqs = ret - 1; |
1171 | state->cur_req = 1; | |
1172 | req = state->reqs[0]; | |
1173 | } else { | |
1174 | req = state->reqs[state->cur_req]; | |
1175 | state->free_reqs--; | |
1176 | state->cur_req++; | |
2b188cc1 JA |
1177 | } |
1178 | ||
0ddf92e8 | 1179 | got_it: |
1a6b74fc | 1180 | req->io = NULL; |
60c112b0 | 1181 | req->file = NULL; |
2579f913 JA |
1182 | req->ctx = ctx; |
1183 | req->flags = 0; | |
e65ef56d JA |
1184 | /* one is dropped after submission, the other at completion */ |
1185 | refcount_set(&req->refs, 2); | |
9e645e11 | 1186 | req->result = 0; |
561fb04a | 1187 | INIT_IO_WORK(&req->work, io_wq_submit_work); |
2579f913 | 1188 | return req; |
0ddf92e8 JA |
1189 | fallback: |
1190 | req = io_get_fallback_req(ctx); | |
1191 | if (req) | |
1192 | goto got_it; | |
6805b32e | 1193 | percpu_ref_put(&ctx->refs); |
2b188cc1 JA |
1194 | return NULL; |
1195 | } | |
1196 | ||
2b85edfc PB |
1197 | static void __io_req_do_free(struct io_kiocb *req) |
1198 | { | |
1199 | if (likely(!io_is_fallback_req(req))) | |
1200 | kmem_cache_free(req_cachep, req); | |
1201 | else | |
1202 | clear_bit_unlock(0, (unsigned long *) req->ctx->fallback_req); | |
1203 | } | |
1204 | ||
c6ca97b3 | 1205 | static void __io_req_aux_free(struct io_kiocb *req) |
2b188cc1 | 1206 | { |
fcb323cc JA |
1207 | struct io_ring_ctx *ctx = req->ctx; |
1208 | ||
96fd84d8 | 1209 | kfree(req->io); |
05f3fb3c JA |
1210 | if (req->file) { |
1211 | if (req->flags & REQ_F_FIXED_FILE) | |
1212 | percpu_ref_put(&ctx->file_data->refs); | |
1213 | else | |
1214 | fput(req->file); | |
1215 | } | |
c6ca97b3 JA |
1216 | } |
1217 | ||
1218 | static void __io_free_req(struct io_kiocb *req) | |
1219 | { | |
1220 | __io_req_aux_free(req); | |
1221 | ||
fcb323cc | 1222 | if (req->flags & REQ_F_INFLIGHT) { |
c6ca97b3 | 1223 | struct io_ring_ctx *ctx = req->ctx; |
fcb323cc JA |
1224 | unsigned long flags; |
1225 | ||
1226 | spin_lock_irqsave(&ctx->inflight_lock, flags); | |
1227 | list_del(&req->inflight_entry); | |
1228 | if (waitqueue_active(&ctx->inflight_wait)) | |
1229 | wake_up(&ctx->inflight_wait); | |
1230 | spin_unlock_irqrestore(&ctx->inflight_lock, flags); | |
1231 | } | |
2b85edfc PB |
1232 | |
1233 | percpu_ref_put(&req->ctx->refs); | |
1234 | __io_req_do_free(req); | |
e65ef56d JA |
1235 | } |
1236 | ||
c6ca97b3 JA |
1237 | struct req_batch { |
1238 | void *reqs[IO_IOPOLL_BATCH]; | |
1239 | int to_free; | |
1240 | int need_iter; | |
1241 | }; | |
1242 | ||
1243 | static void io_free_req_many(struct io_ring_ctx *ctx, struct req_batch *rb) | |
1244 | { | |
10fef4be JA |
1245 | int fixed_refs = rb->to_free; |
1246 | ||
c6ca97b3 JA |
1247 | if (!rb->to_free) |
1248 | return; | |
1249 | if (rb->need_iter) { | |
1250 | int i, inflight = 0; | |
1251 | unsigned long flags; | |
1252 | ||
10fef4be | 1253 | fixed_refs = 0; |
c6ca97b3 JA |
1254 | for (i = 0; i < rb->to_free; i++) { |
1255 | struct io_kiocb *req = rb->reqs[i]; | |
1256 | ||
10fef4be | 1257 | if (req->flags & REQ_F_FIXED_FILE) { |
c6ca97b3 | 1258 | req->file = NULL; |
10fef4be JA |
1259 | fixed_refs++; |
1260 | } | |
c6ca97b3 JA |
1261 | if (req->flags & REQ_F_INFLIGHT) |
1262 | inflight++; | |
c6ca97b3 JA |
1263 | __io_req_aux_free(req); |
1264 | } | |
1265 | if (!inflight) | |
1266 | goto do_free; | |
1267 | ||
1268 | spin_lock_irqsave(&ctx->inflight_lock, flags); | |
1269 | for (i = 0; i < rb->to_free; i++) { | |
1270 | struct io_kiocb *req = rb->reqs[i]; | |
1271 | ||
10fef4be | 1272 | if (req->flags & REQ_F_INFLIGHT) { |
c6ca97b3 JA |
1273 | list_del(&req->inflight_entry); |
1274 | if (!--inflight) | |
1275 | break; | |
1276 | } | |
1277 | } | |
1278 | spin_unlock_irqrestore(&ctx->inflight_lock, flags); | |
1279 | ||
1280 | if (waitqueue_active(&ctx->inflight_wait)) | |
1281 | wake_up(&ctx->inflight_wait); | |
1282 | } | |
1283 | do_free: | |
1284 | kmem_cache_free_bulk(req_cachep, rb->to_free, rb->reqs); | |
10fef4be JA |
1285 | if (fixed_refs) |
1286 | percpu_ref_put_many(&ctx->file_data->refs, fixed_refs); | |
c6ca97b3 | 1287 | percpu_ref_put_many(&ctx->refs, rb->to_free); |
c6ca97b3 JA |
1288 | rb->to_free = rb->need_iter = 0; |
1289 | } | |
1290 | ||
a197f664 | 1291 | static bool io_link_cancel_timeout(struct io_kiocb *req) |
2665abfd | 1292 | { |
a197f664 | 1293 | struct io_ring_ctx *ctx = req->ctx; |
2665abfd JA |
1294 | int ret; |
1295 | ||
2d28390a | 1296 | ret = hrtimer_try_to_cancel(&req->io->timeout.timer); |
2665abfd | 1297 | if (ret != -1) { |
78e19bbe | 1298 | io_cqring_fill_event(req, -ECANCELED); |
2665abfd JA |
1299 | io_commit_cqring(ctx); |
1300 | req->flags &= ~REQ_F_LINK; | |
ec9c02ad | 1301 | io_put_req(req); |
2665abfd JA |
1302 | return true; |
1303 | } | |
1304 | ||
1305 | return false; | |
e65ef56d JA |
1306 | } |
1307 | ||
ba816ad6 | 1308 | static void io_req_link_next(struct io_kiocb *req, struct io_kiocb **nxtptr) |
9e645e11 | 1309 | { |
2665abfd | 1310 | struct io_ring_ctx *ctx = req->ctx; |
2665abfd | 1311 | bool wake_ev = false; |
9e645e11 | 1312 | |
4d7dd462 JA |
1313 | /* Already got next link */ |
1314 | if (req->flags & REQ_F_LINK_NEXT) | |
1315 | return; | |
1316 | ||
9e645e11 JA |
1317 | /* |
1318 | * The list should never be empty when we are called here. But could | |
1319 | * potentially happen if the chain is messed up, check to be on the | |
1320 | * safe side. | |
1321 | */ | |
4493233e PB |
1322 | while (!list_empty(&req->link_list)) { |
1323 | struct io_kiocb *nxt = list_first_entry(&req->link_list, | |
1324 | struct io_kiocb, link_list); | |
94ae5e77 | 1325 | |
4493233e PB |
1326 | if (unlikely((req->flags & REQ_F_LINK_TIMEOUT) && |
1327 | (nxt->flags & REQ_F_TIMEOUT))) { | |
1328 | list_del_init(&nxt->link_list); | |
94ae5e77 | 1329 | wake_ev |= io_link_cancel_timeout(nxt); |
94ae5e77 JA |
1330 | req->flags &= ~REQ_F_LINK_TIMEOUT; |
1331 | continue; | |
1332 | } | |
9e645e11 | 1333 | |
4493233e PB |
1334 | list_del_init(&req->link_list); |
1335 | if (!list_empty(&nxt->link_list)) | |
1336 | nxt->flags |= REQ_F_LINK; | |
b18fdf71 | 1337 | *nxtptr = nxt; |
94ae5e77 | 1338 | break; |
9e645e11 | 1339 | } |
2665abfd | 1340 | |
4d7dd462 | 1341 | req->flags |= REQ_F_LINK_NEXT; |
2665abfd JA |
1342 | if (wake_ev) |
1343 | io_cqring_ev_posted(ctx); | |
9e645e11 JA |
1344 | } |
1345 | ||
1346 | /* | |
1347 | * Called if REQ_F_LINK is set, and we fail the head request | |
1348 | */ | |
1349 | static void io_fail_links(struct io_kiocb *req) | |
1350 | { | |
2665abfd | 1351 | struct io_ring_ctx *ctx = req->ctx; |
2665abfd JA |
1352 | unsigned long flags; |
1353 | ||
1354 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
9e645e11 JA |
1355 | |
1356 | while (!list_empty(&req->link_list)) { | |
4493233e PB |
1357 | struct io_kiocb *link = list_first_entry(&req->link_list, |
1358 | struct io_kiocb, link_list); | |
9e645e11 | 1359 | |
4493233e | 1360 | list_del_init(&link->link_list); |
c826bd7a | 1361 | trace_io_uring_fail_link(req, link); |
2665abfd JA |
1362 | |
1363 | if ((req->flags & REQ_F_LINK_TIMEOUT) && | |
d625c6ee | 1364 | link->opcode == IORING_OP_LINK_TIMEOUT) { |
a197f664 | 1365 | io_link_cancel_timeout(link); |
2665abfd | 1366 | } else { |
78e19bbe | 1367 | io_cqring_fill_event(link, -ECANCELED); |
978db57e | 1368 | __io_double_put_req(link); |
2665abfd | 1369 | } |
5d960724 | 1370 | req->flags &= ~REQ_F_LINK_TIMEOUT; |
9e645e11 | 1371 | } |
2665abfd JA |
1372 | |
1373 | io_commit_cqring(ctx); | |
1374 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
1375 | io_cqring_ev_posted(ctx); | |
9e645e11 JA |
1376 | } |
1377 | ||
4d7dd462 | 1378 | static void io_req_find_next(struct io_kiocb *req, struct io_kiocb **nxt) |
9e645e11 | 1379 | { |
4d7dd462 | 1380 | if (likely(!(req->flags & REQ_F_LINK))) |
2665abfd | 1381 | return; |
2665abfd | 1382 | |
9e645e11 JA |
1383 | /* |
1384 | * If LINK is set, we have dependent requests in this chain. If we | |
1385 | * didn't fail this request, queue the first one up, moving any other | |
1386 | * dependencies to the next request. In case of failure, fail the rest | |
1387 | * of the chain. | |
1388 | */ | |
2665abfd JA |
1389 | if (req->flags & REQ_F_FAIL_LINK) { |
1390 | io_fail_links(req); | |
7c9e7f0f JA |
1391 | } else if ((req->flags & (REQ_F_LINK_TIMEOUT | REQ_F_COMP_LOCKED)) == |
1392 | REQ_F_LINK_TIMEOUT) { | |
2665abfd JA |
1393 | struct io_ring_ctx *ctx = req->ctx; |
1394 | unsigned long flags; | |
1395 | ||
1396 | /* | |
1397 | * If this is a timeout link, we could be racing with the | |
1398 | * timeout timer. Grab the completion lock for this case to | |
7c9e7f0f | 1399 | * protect against that. |
2665abfd JA |
1400 | */ |
1401 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
1402 | io_req_link_next(req, nxt); | |
1403 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
1404 | } else { | |
1405 | io_req_link_next(req, nxt); | |
9e645e11 | 1406 | } |
4d7dd462 | 1407 | } |
9e645e11 | 1408 | |
c69f8dbe JL |
1409 | static void io_free_req(struct io_kiocb *req) |
1410 | { | |
944e58bf PB |
1411 | struct io_kiocb *nxt = NULL; |
1412 | ||
1413 | io_req_find_next(req, &nxt); | |
70cf9f32 | 1414 | __io_free_req(req); |
944e58bf PB |
1415 | |
1416 | if (nxt) | |
1417 | io_queue_async_work(nxt); | |
c69f8dbe JL |
1418 | } |
1419 | ||
ba816ad6 JA |
1420 | /* |
1421 | * Drop reference to request, return next in chain (if there is one) if this | |
1422 | * was the last reference to this request. | |
1423 | */ | |
f9bd67f6 | 1424 | __attribute__((nonnull)) |
ec9c02ad | 1425 | static void io_put_req_find_next(struct io_kiocb *req, struct io_kiocb **nxtptr) |
e65ef56d | 1426 | { |
f9bd67f6 | 1427 | io_req_find_next(req, nxtptr); |
4d7dd462 | 1428 | |
e65ef56d | 1429 | if (refcount_dec_and_test(&req->refs)) |
4d7dd462 | 1430 | __io_free_req(req); |
2b188cc1 JA |
1431 | } |
1432 | ||
e65ef56d JA |
1433 | static void io_put_req(struct io_kiocb *req) |
1434 | { | |
1435 | if (refcount_dec_and_test(&req->refs)) | |
1436 | io_free_req(req); | |
2b188cc1 JA |
1437 | } |
1438 | ||
978db57e JA |
1439 | /* |
1440 | * Must only be used if we don't need to care about links, usually from | |
1441 | * within the completion handling itself. | |
1442 | */ | |
1443 | static void __io_double_put_req(struct io_kiocb *req) | |
78e19bbe JA |
1444 | { |
1445 | /* drop both submit and complete references */ | |
1446 | if (refcount_sub_and_test(2, &req->refs)) | |
1447 | __io_free_req(req); | |
1448 | } | |
1449 | ||
978db57e JA |
1450 | static void io_double_put_req(struct io_kiocb *req) |
1451 | { | |
1452 | /* drop both submit and complete references */ | |
1453 | if (refcount_sub_and_test(2, &req->refs)) | |
1454 | io_free_req(req); | |
1455 | } | |
1456 | ||
1d7bb1d5 | 1457 | static unsigned io_cqring_events(struct io_ring_ctx *ctx, bool noflush) |
a3a0e43f | 1458 | { |
84f97dc2 JA |
1459 | struct io_rings *rings = ctx->rings; |
1460 | ||
ad3eb2c8 JA |
1461 | if (test_bit(0, &ctx->cq_check_overflow)) { |
1462 | /* | |
1463 | * noflush == true is from the waitqueue handler, just ensure | |
1464 | * we wake up the task, and the next invocation will flush the | |
1465 | * entries. We cannot safely to it from here. | |
1466 | */ | |
1467 | if (noflush && !list_empty(&ctx->cq_overflow_list)) | |
1468 | return -1U; | |
1d7bb1d5 | 1469 | |
ad3eb2c8 JA |
1470 | io_cqring_overflow_flush(ctx, false); |
1471 | } | |
1d7bb1d5 | 1472 | |
a3a0e43f JA |
1473 | /* See comment at the top of this file */ |
1474 | smp_rmb(); | |
ad3eb2c8 | 1475 | return ctx->cached_cq_tail - READ_ONCE(rings->cq.head); |
a3a0e43f JA |
1476 | } |
1477 | ||
fb5ccc98 PB |
1478 | static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx) |
1479 | { | |
1480 | struct io_rings *rings = ctx->rings; | |
1481 | ||
1482 | /* make sure SQ entry isn't read before tail */ | |
1483 | return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head; | |
1484 | } | |
1485 | ||
8237e045 | 1486 | static inline bool io_req_multi_free(struct req_batch *rb, struct io_kiocb *req) |
e94f141b | 1487 | { |
c6ca97b3 JA |
1488 | if ((req->flags & REQ_F_LINK) || io_is_fallback_req(req)) |
1489 | return false; | |
e94f141b | 1490 | |
c6ca97b3 JA |
1491 | if (!(req->flags & REQ_F_FIXED_FILE) || req->io) |
1492 | rb->need_iter++; | |
1493 | ||
1494 | rb->reqs[rb->to_free++] = req; | |
1495 | if (unlikely(rb->to_free == ARRAY_SIZE(rb->reqs))) | |
1496 | io_free_req_many(req->ctx, rb); | |
1497 | return true; | |
e94f141b JA |
1498 | } |
1499 | ||
def596e9 JA |
1500 | /* |
1501 | * Find and free completed poll iocbs | |
1502 | */ | |
1503 | static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events, | |
1504 | struct list_head *done) | |
1505 | { | |
8237e045 | 1506 | struct req_batch rb; |
def596e9 | 1507 | struct io_kiocb *req; |
def596e9 | 1508 | |
c6ca97b3 | 1509 | rb.to_free = rb.need_iter = 0; |
def596e9 JA |
1510 | while (!list_empty(done)) { |
1511 | req = list_first_entry(done, struct io_kiocb, list); | |
1512 | list_del(&req->list); | |
1513 | ||
78e19bbe | 1514 | io_cqring_fill_event(req, req->result); |
def596e9 JA |
1515 | (*nr_events)++; |
1516 | ||
8237e045 JA |
1517 | if (refcount_dec_and_test(&req->refs) && |
1518 | !io_req_multi_free(&rb, req)) | |
1519 | io_free_req(req); | |
def596e9 | 1520 | } |
def596e9 | 1521 | |
09bb8394 | 1522 | io_commit_cqring(ctx); |
8237e045 | 1523 | io_free_req_many(ctx, &rb); |
def596e9 JA |
1524 | } |
1525 | ||
1526 | static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, | |
1527 | long min) | |
1528 | { | |
1529 | struct io_kiocb *req, *tmp; | |
1530 | LIST_HEAD(done); | |
1531 | bool spin; | |
1532 | int ret; | |
1533 | ||
1534 | /* | |
1535 | * Only spin for completions if we don't have multiple devices hanging | |
1536 | * off our complete list, and we're under the requested amount. | |
1537 | */ | |
1538 | spin = !ctx->poll_multi_file && *nr_events < min; | |
1539 | ||
1540 | ret = 0; | |
1541 | list_for_each_entry_safe(req, tmp, &ctx->poll_list, list) { | |
9adbd45d | 1542 | struct kiocb *kiocb = &req->rw.kiocb; |
def596e9 JA |
1543 | |
1544 | /* | |
1545 | * Move completed entries to our local list. If we find a | |
1546 | * request that requires polling, break out and complete | |
1547 | * the done list first, if we have entries there. | |
1548 | */ | |
1549 | if (req->flags & REQ_F_IOPOLL_COMPLETED) { | |
1550 | list_move_tail(&req->list, &done); | |
1551 | continue; | |
1552 | } | |
1553 | if (!list_empty(&done)) | |
1554 | break; | |
1555 | ||
1556 | ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin); | |
1557 | if (ret < 0) | |
1558 | break; | |
1559 | ||
1560 | if (ret && spin) | |
1561 | spin = false; | |
1562 | ret = 0; | |
1563 | } | |
1564 | ||
1565 | if (!list_empty(&done)) | |
1566 | io_iopoll_complete(ctx, nr_events, &done); | |
1567 | ||
1568 | return ret; | |
1569 | } | |
1570 | ||
1571 | /* | |
d195a66e | 1572 | * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a |
def596e9 JA |
1573 | * non-spinning poll check - we'll still enter the driver poll loop, but only |
1574 | * as a non-spinning completion check. | |
1575 | */ | |
1576 | static int io_iopoll_getevents(struct io_ring_ctx *ctx, unsigned int *nr_events, | |
1577 | long min) | |
1578 | { | |
08f5439f | 1579 | while (!list_empty(&ctx->poll_list) && !need_resched()) { |
def596e9 JA |
1580 | int ret; |
1581 | ||
1582 | ret = io_do_iopoll(ctx, nr_events, min); | |
1583 | if (ret < 0) | |
1584 | return ret; | |
1585 | if (!min || *nr_events >= min) | |
1586 | return 0; | |
1587 | } | |
1588 | ||
1589 | return 1; | |
1590 | } | |
1591 | ||
1592 | /* | |
1593 | * We can't just wait for polled events to come to us, we have to actively | |
1594 | * find and complete them. | |
1595 | */ | |
1596 | static void io_iopoll_reap_events(struct io_ring_ctx *ctx) | |
1597 | { | |
1598 | if (!(ctx->flags & IORING_SETUP_IOPOLL)) | |
1599 | return; | |
1600 | ||
1601 | mutex_lock(&ctx->uring_lock); | |
1602 | while (!list_empty(&ctx->poll_list)) { | |
1603 | unsigned int nr_events = 0; | |
1604 | ||
1605 | io_iopoll_getevents(ctx, &nr_events, 1); | |
08f5439f JA |
1606 | |
1607 | /* | |
1608 | * Ensure we allow local-to-the-cpu processing to take place, | |
1609 | * in this case we need to ensure that we reap all events. | |
1610 | */ | |
1611 | cond_resched(); | |
def596e9 JA |
1612 | } |
1613 | mutex_unlock(&ctx->uring_lock); | |
1614 | } | |
1615 | ||
2b2ed975 JA |
1616 | static int __io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, |
1617 | long min) | |
def596e9 | 1618 | { |
2b2ed975 | 1619 | int iters = 0, ret = 0; |
500f9fba | 1620 | |
def596e9 JA |
1621 | do { |
1622 | int tmin = 0; | |
1623 | ||
a3a0e43f JA |
1624 | /* |
1625 | * Don't enter poll loop if we already have events pending. | |
1626 | * If we do, we can potentially be spinning for commands that | |
1627 | * already triggered a CQE (eg in error). | |
1628 | */ | |
1d7bb1d5 | 1629 | if (io_cqring_events(ctx, false)) |
a3a0e43f JA |
1630 | break; |
1631 | ||
500f9fba JA |
1632 | /* |
1633 | * If a submit got punted to a workqueue, we can have the | |
1634 | * application entering polling for a command before it gets | |
1635 | * issued. That app will hold the uring_lock for the duration | |
1636 | * of the poll right here, so we need to take a breather every | |
1637 | * now and then to ensure that the issue has a chance to add | |
1638 | * the poll to the issued list. Otherwise we can spin here | |
1639 | * forever, while the workqueue is stuck trying to acquire the | |
1640 | * very same mutex. | |
1641 | */ | |
1642 | if (!(++iters & 7)) { | |
1643 | mutex_unlock(&ctx->uring_lock); | |
1644 | mutex_lock(&ctx->uring_lock); | |
1645 | } | |
1646 | ||
def596e9 JA |
1647 | if (*nr_events < min) |
1648 | tmin = min - *nr_events; | |
1649 | ||
1650 | ret = io_iopoll_getevents(ctx, nr_events, tmin); | |
1651 | if (ret <= 0) | |
1652 | break; | |
1653 | ret = 0; | |
1654 | } while (min && !*nr_events && !need_resched()); | |
1655 | ||
2b2ed975 JA |
1656 | return ret; |
1657 | } | |
1658 | ||
1659 | static int io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, | |
1660 | long min) | |
1661 | { | |
1662 | int ret; | |
1663 | ||
1664 | /* | |
1665 | * We disallow the app entering submit/complete with polling, but we | |
1666 | * still need to lock the ring to prevent racing with polled issue | |
1667 | * that got punted to a workqueue. | |
1668 | */ | |
1669 | mutex_lock(&ctx->uring_lock); | |
1670 | ret = __io_iopoll_check(ctx, nr_events, min); | |
500f9fba | 1671 | mutex_unlock(&ctx->uring_lock); |
def596e9 JA |
1672 | return ret; |
1673 | } | |
1674 | ||
491381ce | 1675 | static void kiocb_end_write(struct io_kiocb *req) |
2b188cc1 | 1676 | { |
491381ce JA |
1677 | /* |
1678 | * Tell lockdep we inherited freeze protection from submission | |
1679 | * thread. | |
1680 | */ | |
1681 | if (req->flags & REQ_F_ISREG) { | |
1682 | struct inode *inode = file_inode(req->file); | |
2b188cc1 | 1683 | |
491381ce | 1684 | __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE); |
2b188cc1 | 1685 | } |
491381ce | 1686 | file_end_write(req->file); |
2b188cc1 JA |
1687 | } |
1688 | ||
4e88d6e7 JA |
1689 | static inline void req_set_fail_links(struct io_kiocb *req) |
1690 | { | |
1691 | if ((req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) == REQ_F_LINK) | |
1692 | req->flags |= REQ_F_FAIL_LINK; | |
1693 | } | |
1694 | ||
ba816ad6 | 1695 | static void io_complete_rw_common(struct kiocb *kiocb, long res) |
2b188cc1 | 1696 | { |
9adbd45d | 1697 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
2b188cc1 | 1698 | |
491381ce JA |
1699 | if (kiocb->ki_flags & IOCB_WRITE) |
1700 | kiocb_end_write(req); | |
2b188cc1 | 1701 | |
4e88d6e7 JA |
1702 | if (res != req->result) |
1703 | req_set_fail_links(req); | |
78e19bbe | 1704 | io_cqring_add_event(req, res); |
ba816ad6 JA |
1705 | } |
1706 | ||
1707 | static void io_complete_rw(struct kiocb *kiocb, long res, long res2) | |
1708 | { | |
9adbd45d | 1709 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
ba816ad6 JA |
1710 | |
1711 | io_complete_rw_common(kiocb, res); | |
e65ef56d | 1712 | io_put_req(req); |
2b188cc1 JA |
1713 | } |
1714 | ||
ba816ad6 JA |
1715 | static struct io_kiocb *__io_complete_rw(struct kiocb *kiocb, long res) |
1716 | { | |
9adbd45d | 1717 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
ec9c02ad | 1718 | struct io_kiocb *nxt = NULL; |
ba816ad6 JA |
1719 | |
1720 | io_complete_rw_common(kiocb, res); | |
ec9c02ad JL |
1721 | io_put_req_find_next(req, &nxt); |
1722 | ||
1723 | return nxt; | |
2b188cc1 JA |
1724 | } |
1725 | ||
def596e9 JA |
1726 | static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2) |
1727 | { | |
9adbd45d | 1728 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
def596e9 | 1729 | |
491381ce JA |
1730 | if (kiocb->ki_flags & IOCB_WRITE) |
1731 | kiocb_end_write(req); | |
def596e9 | 1732 | |
4e88d6e7 JA |
1733 | if (res != req->result) |
1734 | req_set_fail_links(req); | |
9e645e11 | 1735 | req->result = res; |
def596e9 JA |
1736 | if (res != -EAGAIN) |
1737 | req->flags |= REQ_F_IOPOLL_COMPLETED; | |
1738 | } | |
1739 | ||
1740 | /* | |
1741 | * After the iocb has been issued, it's safe to be found on the poll list. | |
1742 | * Adding the kiocb to the list AFTER submission ensures that we don't | |
1743 | * find it from a io_iopoll_getevents() thread before the issuer is done | |
1744 | * accessing the kiocb cookie. | |
1745 | */ | |
1746 | static void io_iopoll_req_issued(struct io_kiocb *req) | |
1747 | { | |
1748 | struct io_ring_ctx *ctx = req->ctx; | |
1749 | ||
1750 | /* | |
1751 | * Track whether we have multiple files in our lists. This will impact | |
1752 | * how we do polling eventually, not spinning if we're on potentially | |
1753 | * different devices. | |
1754 | */ | |
1755 | if (list_empty(&ctx->poll_list)) { | |
1756 | ctx->poll_multi_file = false; | |
1757 | } else if (!ctx->poll_multi_file) { | |
1758 | struct io_kiocb *list_req; | |
1759 | ||
1760 | list_req = list_first_entry(&ctx->poll_list, struct io_kiocb, | |
1761 | list); | |
9adbd45d | 1762 | if (list_req->file != req->file) |
def596e9 JA |
1763 | ctx->poll_multi_file = true; |
1764 | } | |
1765 | ||
1766 | /* | |
1767 | * For fast devices, IO may have already completed. If it has, add | |
1768 | * it to the front so we find it first. | |
1769 | */ | |
1770 | if (req->flags & REQ_F_IOPOLL_COMPLETED) | |
1771 | list_add(&req->list, &ctx->poll_list); | |
1772 | else | |
1773 | list_add_tail(&req->list, &ctx->poll_list); | |
1774 | } | |
1775 | ||
3d6770fb | 1776 | static void io_file_put(struct io_submit_state *state) |
9a56a232 | 1777 | { |
3d6770fb | 1778 | if (state->file) { |
9a56a232 JA |
1779 | int diff = state->has_refs - state->used_refs; |
1780 | ||
1781 | if (diff) | |
1782 | fput_many(state->file, diff); | |
1783 | state->file = NULL; | |
1784 | } | |
1785 | } | |
1786 | ||
1787 | /* | |
1788 | * Get as many references to a file as we have IOs left in this submission, | |
1789 | * assuming most submissions are for one file, or at least that each file | |
1790 | * has more than one submission. | |
1791 | */ | |
1792 | static struct file *io_file_get(struct io_submit_state *state, int fd) | |
1793 | { | |
1794 | if (!state) | |
1795 | return fget(fd); | |
1796 | ||
1797 | if (state->file) { | |
1798 | if (state->fd == fd) { | |
1799 | state->used_refs++; | |
1800 | state->ios_left--; | |
1801 | return state->file; | |
1802 | } | |
3d6770fb | 1803 | io_file_put(state); |
9a56a232 JA |
1804 | } |
1805 | state->file = fget_many(fd, state->ios_left); | |
1806 | if (!state->file) | |
1807 | return NULL; | |
1808 | ||
1809 | state->fd = fd; | |
1810 | state->has_refs = state->ios_left; | |
1811 | state->used_refs = 1; | |
1812 | state->ios_left--; | |
1813 | return state->file; | |
1814 | } | |
1815 | ||
2b188cc1 JA |
1816 | /* |
1817 | * If we tracked the file through the SCM inflight mechanism, we could support | |
1818 | * any file. For now, just ensure that anything potentially problematic is done | |
1819 | * inline. | |
1820 | */ | |
1821 | static bool io_file_supports_async(struct file *file) | |
1822 | { | |
1823 | umode_t mode = file_inode(file)->i_mode; | |
1824 | ||
10d59345 | 1825 | if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISSOCK(mode)) |
2b188cc1 JA |
1826 | return true; |
1827 | if (S_ISREG(mode) && file->f_op != &io_uring_fops) | |
1828 | return true; | |
1829 | ||
1830 | return false; | |
1831 | } | |
1832 | ||
3529d8c2 JA |
1833 | static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
1834 | bool force_nonblock) | |
2b188cc1 | 1835 | { |
def596e9 | 1836 | struct io_ring_ctx *ctx = req->ctx; |
9adbd45d | 1837 | struct kiocb *kiocb = &req->rw.kiocb; |
09bb8394 JA |
1838 | unsigned ioprio; |
1839 | int ret; | |
2b188cc1 | 1840 | |
09bb8394 JA |
1841 | if (!req->file) |
1842 | return -EBADF; | |
2b188cc1 | 1843 | |
491381ce JA |
1844 | if (S_ISREG(file_inode(req->file)->i_mode)) |
1845 | req->flags |= REQ_F_ISREG; | |
1846 | ||
2b188cc1 | 1847 | kiocb->ki_pos = READ_ONCE(sqe->off); |
ba04291e JA |
1848 | if (kiocb->ki_pos == -1 && !(req->file->f_mode & FMODE_STREAM)) { |
1849 | req->flags |= REQ_F_CUR_POS; | |
1850 | kiocb->ki_pos = req->file->f_pos; | |
1851 | } | |
2b188cc1 JA |
1852 | kiocb->ki_flags = iocb_flags(kiocb->ki_filp); |
1853 | kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp)); | |
1854 | ||
1855 | ioprio = READ_ONCE(sqe->ioprio); | |
1856 | if (ioprio) { | |
1857 | ret = ioprio_check_cap(ioprio); | |
1858 | if (ret) | |
09bb8394 | 1859 | return ret; |
2b188cc1 JA |
1860 | |
1861 | kiocb->ki_ioprio = ioprio; | |
1862 | } else | |
1863 | kiocb->ki_ioprio = get_current_ioprio(); | |
1864 | ||
1865 | ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags)); | |
1866 | if (unlikely(ret)) | |
09bb8394 | 1867 | return ret; |
8449eeda SB |
1868 | |
1869 | /* don't allow async punt if RWF_NOWAIT was requested */ | |
491381ce JA |
1870 | if ((kiocb->ki_flags & IOCB_NOWAIT) || |
1871 | (req->file->f_flags & O_NONBLOCK)) | |
8449eeda SB |
1872 | req->flags |= REQ_F_NOWAIT; |
1873 | ||
1874 | if (force_nonblock) | |
2b188cc1 | 1875 | kiocb->ki_flags |= IOCB_NOWAIT; |
8449eeda | 1876 | |
def596e9 | 1877 | if (ctx->flags & IORING_SETUP_IOPOLL) { |
def596e9 JA |
1878 | if (!(kiocb->ki_flags & IOCB_DIRECT) || |
1879 | !kiocb->ki_filp->f_op->iopoll) | |
09bb8394 | 1880 | return -EOPNOTSUPP; |
2b188cc1 | 1881 | |
def596e9 JA |
1882 | kiocb->ki_flags |= IOCB_HIPRI; |
1883 | kiocb->ki_complete = io_complete_rw_iopoll; | |
6873e0bd | 1884 | req->result = 0; |
def596e9 | 1885 | } else { |
09bb8394 JA |
1886 | if (kiocb->ki_flags & IOCB_HIPRI) |
1887 | return -EINVAL; | |
def596e9 JA |
1888 | kiocb->ki_complete = io_complete_rw; |
1889 | } | |
9adbd45d | 1890 | |
3529d8c2 JA |
1891 | req->rw.addr = READ_ONCE(sqe->addr); |
1892 | req->rw.len = READ_ONCE(sqe->len); | |
9adbd45d JA |
1893 | /* we own ->private, reuse it for the buffer index */ |
1894 | req->rw.kiocb.private = (void *) (unsigned long) | |
3529d8c2 | 1895 | READ_ONCE(sqe->buf_index); |
2b188cc1 | 1896 | return 0; |
2b188cc1 JA |
1897 | } |
1898 | ||
1899 | static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret) | |
1900 | { | |
1901 | switch (ret) { | |
1902 | case -EIOCBQUEUED: | |
1903 | break; | |
1904 | case -ERESTARTSYS: | |
1905 | case -ERESTARTNOINTR: | |
1906 | case -ERESTARTNOHAND: | |
1907 | case -ERESTART_RESTARTBLOCK: | |
1908 | /* | |
1909 | * We can't just restart the syscall, since previously | |
1910 | * submitted sqes may already be in progress. Just fail this | |
1911 | * IO with EINTR. | |
1912 | */ | |
1913 | ret = -EINTR; | |
1914 | /* fall through */ | |
1915 | default: | |
1916 | kiocb->ki_complete(kiocb, ret, 0); | |
1917 | } | |
1918 | } | |
1919 | ||
ba816ad6 JA |
1920 | static void kiocb_done(struct kiocb *kiocb, ssize_t ret, struct io_kiocb **nxt, |
1921 | bool in_async) | |
1922 | { | |
ba04291e JA |
1923 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
1924 | ||
1925 | if (req->flags & REQ_F_CUR_POS) | |
1926 | req->file->f_pos = kiocb->ki_pos; | |
f9bd67f6 | 1927 | if (in_async && ret >= 0 && kiocb->ki_complete == io_complete_rw) |
ba816ad6 JA |
1928 | *nxt = __io_complete_rw(kiocb, ret); |
1929 | else | |
1930 | io_rw_done(kiocb, ret); | |
1931 | } | |
1932 | ||
9adbd45d | 1933 | static ssize_t io_import_fixed(struct io_kiocb *req, int rw, |
7d009165 | 1934 | struct iov_iter *iter) |
edafccee | 1935 | { |
9adbd45d JA |
1936 | struct io_ring_ctx *ctx = req->ctx; |
1937 | size_t len = req->rw.len; | |
edafccee JA |
1938 | struct io_mapped_ubuf *imu; |
1939 | unsigned index, buf_index; | |
1940 | size_t offset; | |
1941 | u64 buf_addr; | |
1942 | ||
1943 | /* attempt to use fixed buffers without having provided iovecs */ | |
1944 | if (unlikely(!ctx->user_bufs)) | |
1945 | return -EFAULT; | |
1946 | ||
9adbd45d | 1947 | buf_index = (unsigned long) req->rw.kiocb.private; |
edafccee JA |
1948 | if (unlikely(buf_index >= ctx->nr_user_bufs)) |
1949 | return -EFAULT; | |
1950 | ||
1951 | index = array_index_nospec(buf_index, ctx->nr_user_bufs); | |
1952 | imu = &ctx->user_bufs[index]; | |
9adbd45d | 1953 | buf_addr = req->rw.addr; |
edafccee JA |
1954 | |
1955 | /* overflow */ | |
1956 | if (buf_addr + len < buf_addr) | |
1957 | return -EFAULT; | |
1958 | /* not inside the mapped region */ | |
1959 | if (buf_addr < imu->ubuf || buf_addr + len > imu->ubuf + imu->len) | |
1960 | return -EFAULT; | |
1961 | ||
1962 | /* | |
1963 | * May not be a start of buffer, set size appropriately | |
1964 | * and advance us to the beginning. | |
1965 | */ | |
1966 | offset = buf_addr - imu->ubuf; | |
1967 | iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len); | |
bd11b3a3 JA |
1968 | |
1969 | if (offset) { | |
1970 | /* | |
1971 | * Don't use iov_iter_advance() here, as it's really slow for | |
1972 | * using the latter parts of a big fixed buffer - it iterates | |
1973 | * over each segment manually. We can cheat a bit here, because | |
1974 | * we know that: | |
1975 | * | |
1976 | * 1) it's a BVEC iter, we set it up | |
1977 | * 2) all bvecs are PAGE_SIZE in size, except potentially the | |
1978 | * first and last bvec | |
1979 | * | |
1980 | * So just find our index, and adjust the iterator afterwards. | |
1981 | * If the offset is within the first bvec (or the whole first | |
1982 | * bvec, just use iov_iter_advance(). This makes it easier | |
1983 | * since we can just skip the first segment, which may not | |
1984 | * be PAGE_SIZE aligned. | |
1985 | */ | |
1986 | const struct bio_vec *bvec = imu->bvec; | |
1987 | ||
1988 | if (offset <= bvec->bv_len) { | |
1989 | iov_iter_advance(iter, offset); | |
1990 | } else { | |
1991 | unsigned long seg_skip; | |
1992 | ||
1993 | /* skip first vec */ | |
1994 | offset -= bvec->bv_len; | |
1995 | seg_skip = 1 + (offset >> PAGE_SHIFT); | |
1996 | ||
1997 | iter->bvec = bvec + seg_skip; | |
1998 | iter->nr_segs -= seg_skip; | |
99c79f66 | 1999 | iter->count -= bvec->bv_len + offset; |
bd11b3a3 | 2000 | iter->iov_offset = offset & ~PAGE_MASK; |
bd11b3a3 JA |
2001 | } |
2002 | } | |
2003 | ||
5e559561 | 2004 | return len; |
edafccee JA |
2005 | } |
2006 | ||
cf6fd4bd PB |
2007 | static ssize_t io_import_iovec(int rw, struct io_kiocb *req, |
2008 | struct iovec **iovec, struct iov_iter *iter) | |
2b188cc1 | 2009 | { |
9adbd45d JA |
2010 | void __user *buf = u64_to_user_ptr(req->rw.addr); |
2011 | size_t sqe_len = req->rw.len; | |
edafccee JA |
2012 | u8 opcode; |
2013 | ||
d625c6ee | 2014 | opcode = req->opcode; |
7d009165 | 2015 | if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) { |
edafccee | 2016 | *iovec = NULL; |
9adbd45d | 2017 | return io_import_fixed(req, rw, iter); |
edafccee | 2018 | } |
2b188cc1 | 2019 | |
9adbd45d JA |
2020 | /* buffer index only valid with fixed read/write */ |
2021 | if (req->rw.kiocb.private) | |
2022 | return -EINVAL; | |
2023 | ||
3a6820f2 JA |
2024 | if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) { |
2025 | ssize_t ret; | |
2026 | ret = import_single_range(rw, buf, sqe_len, *iovec, iter); | |
2027 | *iovec = NULL; | |
2028 | return ret; | |
2029 | } | |
2030 | ||
f67676d1 JA |
2031 | if (req->io) { |
2032 | struct io_async_rw *iorw = &req->io->rw; | |
2033 | ||
2034 | *iovec = iorw->iov; | |
2035 | iov_iter_init(iter, rw, *iovec, iorw->nr_segs, iorw->size); | |
2036 | if (iorw->iov == iorw->fast_iov) | |
2037 | *iovec = NULL; | |
2038 | return iorw->size; | |
2039 | } | |
2040 | ||
cf6fd4bd | 2041 | if (!req->has_user) |
2b188cc1 JA |
2042 | return -EFAULT; |
2043 | ||
2044 | #ifdef CONFIG_COMPAT | |
cf6fd4bd | 2045 | if (req->ctx->compat) |
2b188cc1 JA |
2046 | return compat_import_iovec(rw, buf, sqe_len, UIO_FASTIOV, |
2047 | iovec, iter); | |
2048 | #endif | |
2049 | ||
2050 | return import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter); | |
2051 | } | |
2052 | ||
31b51510 | 2053 | /* |
32960613 JA |
2054 | * For files that don't have ->read_iter() and ->write_iter(), handle them |
2055 | * by looping over ->read() or ->write() manually. | |
31b51510 | 2056 | */ |
32960613 JA |
2057 | static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb, |
2058 | struct iov_iter *iter) | |
2059 | { | |
2060 | ssize_t ret = 0; | |
2061 | ||
2062 | /* | |
2063 | * Don't support polled IO through this interface, and we can't | |
2064 | * support non-blocking either. For the latter, this just causes | |
2065 | * the kiocb to be handled from an async context. | |
2066 | */ | |
2067 | if (kiocb->ki_flags & IOCB_HIPRI) | |
2068 | return -EOPNOTSUPP; | |
2069 | if (kiocb->ki_flags & IOCB_NOWAIT) | |
2070 | return -EAGAIN; | |
2071 | ||
2072 | while (iov_iter_count(iter)) { | |
311ae9e1 | 2073 | struct iovec iovec; |
32960613 JA |
2074 | ssize_t nr; |
2075 | ||
311ae9e1 PB |
2076 | if (!iov_iter_is_bvec(iter)) { |
2077 | iovec = iov_iter_iovec(iter); | |
2078 | } else { | |
2079 | /* fixed buffers import bvec */ | |
2080 | iovec.iov_base = kmap(iter->bvec->bv_page) | |
2081 | + iter->iov_offset; | |
2082 | iovec.iov_len = min(iter->count, | |
2083 | iter->bvec->bv_len - iter->iov_offset); | |
2084 | } | |
2085 | ||
32960613 JA |
2086 | if (rw == READ) { |
2087 | nr = file->f_op->read(file, iovec.iov_base, | |
2088 | iovec.iov_len, &kiocb->ki_pos); | |
2089 | } else { | |
2090 | nr = file->f_op->write(file, iovec.iov_base, | |
2091 | iovec.iov_len, &kiocb->ki_pos); | |
2092 | } | |
2093 | ||
311ae9e1 PB |
2094 | if (iov_iter_is_bvec(iter)) |
2095 | kunmap(iter->bvec->bv_page); | |
2096 | ||
32960613 JA |
2097 | if (nr < 0) { |
2098 | if (!ret) | |
2099 | ret = nr; | |
2100 | break; | |
2101 | } | |
2102 | ret += nr; | |
2103 | if (nr != iovec.iov_len) | |
2104 | break; | |
2105 | iov_iter_advance(iter, nr); | |
2106 | } | |
2107 | ||
2108 | return ret; | |
2109 | } | |
2110 | ||
b7bb4f7d | 2111 | static void io_req_map_rw(struct io_kiocb *req, ssize_t io_size, |
f67676d1 JA |
2112 | struct iovec *iovec, struct iovec *fast_iov, |
2113 | struct iov_iter *iter) | |
2114 | { | |
2115 | req->io->rw.nr_segs = iter->nr_segs; | |
2116 | req->io->rw.size = io_size; | |
2117 | req->io->rw.iov = iovec; | |
2118 | if (!req->io->rw.iov) { | |
2119 | req->io->rw.iov = req->io->rw.fast_iov; | |
2120 | memcpy(req->io->rw.iov, fast_iov, | |
2121 | sizeof(struct iovec) * iter->nr_segs); | |
2122 | } | |
2123 | } | |
2124 | ||
b7bb4f7d | 2125 | static int io_alloc_async_ctx(struct io_kiocb *req) |
f67676d1 | 2126 | { |
d3656344 JA |
2127 | if (!io_op_defs[req->opcode].async_ctx) |
2128 | return 0; | |
f67676d1 | 2129 | req->io = kmalloc(sizeof(*req->io), GFP_KERNEL); |
06b76d44 | 2130 | return req->io == NULL; |
b7bb4f7d JA |
2131 | } |
2132 | ||
2133 | static void io_rw_async(struct io_wq_work **workptr) | |
2134 | { | |
2135 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2136 | struct iovec *iov = NULL; | |
2137 | ||
2138 | if (req->io->rw.iov != req->io->rw.fast_iov) | |
2139 | iov = req->io->rw.iov; | |
2140 | io_wq_submit_work(workptr); | |
2141 | kfree(iov); | |
2142 | } | |
2143 | ||
2144 | static int io_setup_async_rw(struct io_kiocb *req, ssize_t io_size, | |
2145 | struct iovec *iovec, struct iovec *fast_iov, | |
2146 | struct iov_iter *iter) | |
2147 | { | |
74566df3 JA |
2148 | if (req->opcode == IORING_OP_READ_FIXED || |
2149 | req->opcode == IORING_OP_WRITE_FIXED) | |
2150 | return 0; | |
b7bb4f7d JA |
2151 | if (!req->io && io_alloc_async_ctx(req)) |
2152 | return -ENOMEM; | |
2153 | ||
2154 | io_req_map_rw(req, io_size, iovec, fast_iov, iter); | |
2155 | req->work.func = io_rw_async; | |
2156 | return 0; | |
f67676d1 JA |
2157 | } |
2158 | ||
3529d8c2 JA |
2159 | static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
2160 | bool force_nonblock) | |
f67676d1 | 2161 | { |
3529d8c2 JA |
2162 | struct io_async_ctx *io; |
2163 | struct iov_iter iter; | |
f67676d1 JA |
2164 | ssize_t ret; |
2165 | ||
3529d8c2 JA |
2166 | ret = io_prep_rw(req, sqe, force_nonblock); |
2167 | if (ret) | |
2168 | return ret; | |
f67676d1 | 2169 | |
3529d8c2 JA |
2170 | if (unlikely(!(req->file->f_mode & FMODE_READ))) |
2171 | return -EBADF; | |
f67676d1 | 2172 | |
3529d8c2 JA |
2173 | if (!req->io) |
2174 | return 0; | |
2175 | ||
2176 | io = req->io; | |
2177 | io->rw.iov = io->rw.fast_iov; | |
2178 | req->io = NULL; | |
2179 | ret = io_import_iovec(READ, req, &io->rw.iov, &iter); | |
2180 | req->io = io; | |
2181 | if (ret < 0) | |
2182 | return ret; | |
2183 | ||
2184 | io_req_map_rw(req, ret, io->rw.iov, io->rw.fast_iov, &iter); | |
2185 | return 0; | |
f67676d1 JA |
2186 | } |
2187 | ||
267bc904 | 2188 | static int io_read(struct io_kiocb *req, struct io_kiocb **nxt, |
8358e3a8 | 2189 | bool force_nonblock) |
2b188cc1 JA |
2190 | { |
2191 | struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; | |
9adbd45d | 2192 | struct kiocb *kiocb = &req->rw.kiocb; |
2b188cc1 | 2193 | struct iov_iter iter; |
31b51510 | 2194 | size_t iov_count; |
f67676d1 | 2195 | ssize_t io_size, ret; |
2b188cc1 | 2196 | |
3529d8c2 | 2197 | ret = io_import_iovec(READ, req, &iovec, &iter); |
06b76d44 JA |
2198 | if (ret < 0) |
2199 | return ret; | |
2b188cc1 | 2200 | |
fd6c2e4c JA |
2201 | /* Ensure we clear previously set non-block flag */ |
2202 | if (!force_nonblock) | |
9adbd45d | 2203 | req->rw.kiocb.ki_flags &= ~IOCB_NOWAIT; |
fd6c2e4c | 2204 | |
797f3f53 | 2205 | req->result = 0; |
f67676d1 | 2206 | io_size = ret; |
9e645e11 | 2207 | if (req->flags & REQ_F_LINK) |
f67676d1 JA |
2208 | req->result = io_size; |
2209 | ||
2210 | /* | |
2211 | * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so | |
2212 | * we know to async punt it even if it was opened O_NONBLOCK | |
2213 | */ | |
9adbd45d | 2214 | if (force_nonblock && !io_file_supports_async(req->file)) { |
f67676d1 JA |
2215 | req->flags |= REQ_F_MUST_PUNT; |
2216 | goto copy_iov; | |
2217 | } | |
9e645e11 | 2218 | |
31b51510 | 2219 | iov_count = iov_iter_count(&iter); |
9adbd45d | 2220 | ret = rw_verify_area(READ, req->file, &kiocb->ki_pos, iov_count); |
2b188cc1 JA |
2221 | if (!ret) { |
2222 | ssize_t ret2; | |
2223 | ||
9adbd45d JA |
2224 | if (req->file->f_op->read_iter) |
2225 | ret2 = call_read_iter(req->file, kiocb, &iter); | |
32960613 | 2226 | else |
9adbd45d | 2227 | ret2 = loop_rw_iter(READ, req->file, kiocb, &iter); |
32960613 | 2228 | |
9d93a3f5 | 2229 | /* Catch -EAGAIN return for forced non-blocking submission */ |
f67676d1 | 2230 | if (!force_nonblock || ret2 != -EAGAIN) { |
cf6fd4bd | 2231 | kiocb_done(kiocb, ret2, nxt, req->in_async); |
f67676d1 JA |
2232 | } else { |
2233 | copy_iov: | |
b7bb4f7d | 2234 | ret = io_setup_async_rw(req, io_size, iovec, |
f67676d1 JA |
2235 | inline_vecs, &iter); |
2236 | if (ret) | |
2237 | goto out_free; | |
2238 | return -EAGAIN; | |
2239 | } | |
2b188cc1 | 2240 | } |
f67676d1 | 2241 | out_free: |
b7bb4f7d JA |
2242 | if (!io_wq_current_is_worker()) |
2243 | kfree(iovec); | |
2b188cc1 JA |
2244 | return ret; |
2245 | } | |
2246 | ||
3529d8c2 JA |
2247 | static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
2248 | bool force_nonblock) | |
f67676d1 | 2249 | { |
3529d8c2 JA |
2250 | struct io_async_ctx *io; |
2251 | struct iov_iter iter; | |
f67676d1 JA |
2252 | ssize_t ret; |
2253 | ||
3529d8c2 JA |
2254 | ret = io_prep_rw(req, sqe, force_nonblock); |
2255 | if (ret) | |
2256 | return ret; | |
f67676d1 | 2257 | |
3529d8c2 JA |
2258 | if (unlikely(!(req->file->f_mode & FMODE_WRITE))) |
2259 | return -EBADF; | |
f67676d1 | 2260 | |
3529d8c2 JA |
2261 | if (!req->io) |
2262 | return 0; | |
2263 | ||
2264 | io = req->io; | |
2265 | io->rw.iov = io->rw.fast_iov; | |
2266 | req->io = NULL; | |
2267 | ret = io_import_iovec(WRITE, req, &io->rw.iov, &iter); | |
2268 | req->io = io; | |
2269 | if (ret < 0) | |
2270 | return ret; | |
2271 | ||
2272 | io_req_map_rw(req, ret, io->rw.iov, io->rw.fast_iov, &iter); | |
2273 | return 0; | |
f67676d1 JA |
2274 | } |
2275 | ||
267bc904 | 2276 | static int io_write(struct io_kiocb *req, struct io_kiocb **nxt, |
8358e3a8 | 2277 | bool force_nonblock) |
2b188cc1 JA |
2278 | { |
2279 | struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; | |
9adbd45d | 2280 | struct kiocb *kiocb = &req->rw.kiocb; |
2b188cc1 | 2281 | struct iov_iter iter; |
31b51510 | 2282 | size_t iov_count; |
f67676d1 | 2283 | ssize_t ret, io_size; |
2b188cc1 | 2284 | |
3529d8c2 | 2285 | ret = io_import_iovec(WRITE, req, &iovec, &iter); |
06b76d44 JA |
2286 | if (ret < 0) |
2287 | return ret; | |
2b188cc1 | 2288 | |
fd6c2e4c JA |
2289 | /* Ensure we clear previously set non-block flag */ |
2290 | if (!force_nonblock) | |
9adbd45d | 2291 | req->rw.kiocb.ki_flags &= ~IOCB_NOWAIT; |
fd6c2e4c | 2292 | |
797f3f53 | 2293 | req->result = 0; |
f67676d1 | 2294 | io_size = ret; |
9e645e11 | 2295 | if (req->flags & REQ_F_LINK) |
f67676d1 | 2296 | req->result = io_size; |
9e645e11 | 2297 | |
f67676d1 JA |
2298 | /* |
2299 | * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so | |
2300 | * we know to async punt it even if it was opened O_NONBLOCK | |
2301 | */ | |
2302 | if (force_nonblock && !io_file_supports_async(req->file)) { | |
2303 | req->flags |= REQ_F_MUST_PUNT; | |
2304 | goto copy_iov; | |
2305 | } | |
31b51510 | 2306 | |
10d59345 JA |
2307 | /* file path doesn't support NOWAIT for non-direct_IO */ |
2308 | if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) && | |
2309 | (req->flags & REQ_F_ISREG)) | |
f67676d1 | 2310 | goto copy_iov; |
31b51510 | 2311 | |
f67676d1 | 2312 | iov_count = iov_iter_count(&iter); |
9adbd45d | 2313 | ret = rw_verify_area(WRITE, req->file, &kiocb->ki_pos, iov_count); |
2b188cc1 | 2314 | if (!ret) { |
9bf7933f RP |
2315 | ssize_t ret2; |
2316 | ||
2b188cc1 JA |
2317 | /* |
2318 | * Open-code file_start_write here to grab freeze protection, | |
2319 | * which will be released by another thread in | |
2320 | * io_complete_rw(). Fool lockdep by telling it the lock got | |
2321 | * released so that it doesn't complain about the held lock when | |
2322 | * we return to userspace. | |
2323 | */ | |
491381ce | 2324 | if (req->flags & REQ_F_ISREG) { |
9adbd45d | 2325 | __sb_start_write(file_inode(req->file)->i_sb, |
2b188cc1 | 2326 | SB_FREEZE_WRITE, true); |
9adbd45d | 2327 | __sb_writers_release(file_inode(req->file)->i_sb, |
2b188cc1 JA |
2328 | SB_FREEZE_WRITE); |
2329 | } | |
2330 | kiocb->ki_flags |= IOCB_WRITE; | |
9bf7933f | 2331 | |
9adbd45d JA |
2332 | if (req->file->f_op->write_iter) |
2333 | ret2 = call_write_iter(req->file, kiocb, &iter); | |
32960613 | 2334 | else |
9adbd45d | 2335 | ret2 = loop_rw_iter(WRITE, req->file, kiocb, &iter); |
f67676d1 | 2336 | if (!force_nonblock || ret2 != -EAGAIN) { |
cf6fd4bd | 2337 | kiocb_done(kiocb, ret2, nxt, req->in_async); |
f67676d1 JA |
2338 | } else { |
2339 | copy_iov: | |
b7bb4f7d | 2340 | ret = io_setup_async_rw(req, io_size, iovec, |
f67676d1 JA |
2341 | inline_vecs, &iter); |
2342 | if (ret) | |
2343 | goto out_free; | |
2344 | return -EAGAIN; | |
2345 | } | |
2b188cc1 | 2346 | } |
31b51510 | 2347 | out_free: |
b7bb4f7d JA |
2348 | if (!io_wq_current_is_worker()) |
2349 | kfree(iovec); | |
2b188cc1 JA |
2350 | return ret; |
2351 | } | |
2352 | ||
2353 | /* | |
2354 | * IORING_OP_NOP just posts a completion event, nothing else. | |
2355 | */ | |
78e19bbe | 2356 | static int io_nop(struct io_kiocb *req) |
2b188cc1 JA |
2357 | { |
2358 | struct io_ring_ctx *ctx = req->ctx; | |
2b188cc1 | 2359 | |
def596e9 JA |
2360 | if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) |
2361 | return -EINVAL; | |
2362 | ||
78e19bbe | 2363 | io_cqring_add_event(req, 0); |
e65ef56d | 2364 | io_put_req(req); |
2b188cc1 JA |
2365 | return 0; |
2366 | } | |
2367 | ||
3529d8c2 | 2368 | static int io_prep_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
c992fe29 | 2369 | { |
6b06314c | 2370 | struct io_ring_ctx *ctx = req->ctx; |
c992fe29 | 2371 | |
09bb8394 JA |
2372 | if (!req->file) |
2373 | return -EBADF; | |
c992fe29 | 2374 | |
6b06314c | 2375 | if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) |
def596e9 | 2376 | return -EINVAL; |
edafccee | 2377 | if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index)) |
c992fe29 CH |
2378 | return -EINVAL; |
2379 | ||
8ed8d3c3 JA |
2380 | req->sync.flags = READ_ONCE(sqe->fsync_flags); |
2381 | if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC)) | |
2382 | return -EINVAL; | |
2383 | ||
2384 | req->sync.off = READ_ONCE(sqe->off); | |
2385 | req->sync.len = READ_ONCE(sqe->len); | |
c992fe29 CH |
2386 | return 0; |
2387 | } | |
2388 | ||
8ed8d3c3 JA |
2389 | static bool io_req_cancelled(struct io_kiocb *req) |
2390 | { | |
2391 | if (req->work.flags & IO_WQ_WORK_CANCEL) { | |
2392 | req_set_fail_links(req); | |
2393 | io_cqring_add_event(req, -ECANCELED); | |
2394 | io_put_req(req); | |
2395 | return true; | |
2396 | } | |
2397 | ||
2398 | return false; | |
2399 | } | |
2400 | ||
78912934 JA |
2401 | static void io_link_work_cb(struct io_wq_work **workptr) |
2402 | { | |
2403 | struct io_wq_work *work = *workptr; | |
2404 | struct io_kiocb *link = work->data; | |
2405 | ||
2406 | io_queue_linked_timeout(link); | |
2407 | work->func = io_wq_submit_work; | |
2408 | } | |
2409 | ||
2410 | static void io_wq_assign_next(struct io_wq_work **workptr, struct io_kiocb *nxt) | |
2411 | { | |
2412 | struct io_kiocb *link; | |
2413 | ||
2414 | io_prep_async_work(nxt, &link); | |
2415 | *workptr = &nxt->work; | |
2416 | if (link) { | |
2417 | nxt->work.flags |= IO_WQ_WORK_CB; | |
2418 | nxt->work.func = io_link_work_cb; | |
2419 | nxt->work.data = link; | |
2420 | } | |
2421 | } | |
2422 | ||
8ed8d3c3 JA |
2423 | static void io_fsync_finish(struct io_wq_work **workptr) |
2424 | { | |
2425 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2426 | loff_t end = req->sync.off + req->sync.len; | |
2427 | struct io_kiocb *nxt = NULL; | |
2428 | int ret; | |
2429 | ||
2430 | if (io_req_cancelled(req)) | |
2431 | return; | |
2432 | ||
9adbd45d | 2433 | ret = vfs_fsync_range(req->file, req->sync.off, |
8ed8d3c3 JA |
2434 | end > 0 ? end : LLONG_MAX, |
2435 | req->sync.flags & IORING_FSYNC_DATASYNC); | |
2436 | if (ret < 0) | |
2437 | req_set_fail_links(req); | |
2438 | io_cqring_add_event(req, ret); | |
2439 | io_put_req_find_next(req, &nxt); | |
2440 | if (nxt) | |
78912934 | 2441 | io_wq_assign_next(workptr, nxt); |
8ed8d3c3 JA |
2442 | } |
2443 | ||
fc4df999 JA |
2444 | static int io_fsync(struct io_kiocb *req, struct io_kiocb **nxt, |
2445 | bool force_nonblock) | |
c992fe29 | 2446 | { |
8ed8d3c3 | 2447 | struct io_wq_work *work, *old_work; |
c992fe29 CH |
2448 | |
2449 | /* fsync always requires a blocking context */ | |
8ed8d3c3 JA |
2450 | if (force_nonblock) { |
2451 | io_put_req(req); | |
2452 | req->work.func = io_fsync_finish; | |
c992fe29 | 2453 | return -EAGAIN; |
8ed8d3c3 | 2454 | } |
c992fe29 | 2455 | |
8ed8d3c3 JA |
2456 | work = old_work = &req->work; |
2457 | io_fsync_finish(&work); | |
2458 | if (work && work != old_work) | |
2459 | *nxt = container_of(work, struct io_kiocb, work); | |
c992fe29 CH |
2460 | return 0; |
2461 | } | |
2462 | ||
d63d1b5e JA |
2463 | static void io_fallocate_finish(struct io_wq_work **workptr) |
2464 | { | |
2465 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2466 | struct io_kiocb *nxt = NULL; | |
2467 | int ret; | |
2468 | ||
2469 | ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off, | |
2470 | req->sync.len); | |
2471 | if (ret < 0) | |
2472 | req_set_fail_links(req); | |
2473 | io_cqring_add_event(req, ret); | |
2474 | io_put_req_find_next(req, &nxt); | |
2475 | if (nxt) | |
2476 | io_wq_assign_next(workptr, nxt); | |
2477 | } | |
2478 | ||
2479 | static int io_fallocate_prep(struct io_kiocb *req, | |
2480 | const struct io_uring_sqe *sqe) | |
2481 | { | |
2482 | if (sqe->ioprio || sqe->buf_index || sqe->rw_flags) | |
2483 | return -EINVAL; | |
2484 | ||
2485 | req->sync.off = READ_ONCE(sqe->off); | |
2486 | req->sync.len = READ_ONCE(sqe->addr); | |
2487 | req->sync.mode = READ_ONCE(sqe->len); | |
2488 | return 0; | |
2489 | } | |
2490 | ||
2491 | static int io_fallocate(struct io_kiocb *req, struct io_kiocb **nxt, | |
2492 | bool force_nonblock) | |
2493 | { | |
2494 | struct io_wq_work *work, *old_work; | |
2495 | ||
2496 | /* fallocate always requiring blocking context */ | |
2497 | if (force_nonblock) { | |
2498 | io_put_req(req); | |
2499 | req->work.func = io_fallocate_finish; | |
2500 | return -EAGAIN; | |
2501 | } | |
2502 | ||
2503 | work = old_work = &req->work; | |
2504 | io_fallocate_finish(&work); | |
2505 | if (work && work != old_work) | |
2506 | *nxt = container_of(work, struct io_kiocb, work); | |
2507 | ||
2508 | return 0; | |
2509 | } | |
2510 | ||
15b71abe JA |
2511 | static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2512 | { | |
f8748881 | 2513 | const char __user *fname; |
15b71abe JA |
2514 | int ret; |
2515 | ||
2516 | if (sqe->ioprio || sqe->buf_index) | |
2517 | return -EINVAL; | |
2518 | ||
2519 | req->open.dfd = READ_ONCE(sqe->fd); | |
c12cedf2 | 2520 | req->open.how.mode = READ_ONCE(sqe->len); |
f8748881 | 2521 | fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); |
c12cedf2 | 2522 | req->open.how.flags = READ_ONCE(sqe->open_flags); |
15b71abe | 2523 | |
f8748881 | 2524 | req->open.filename = getname(fname); |
15b71abe JA |
2525 | if (IS_ERR(req->open.filename)) { |
2526 | ret = PTR_ERR(req->open.filename); | |
2527 | req->open.filename = NULL; | |
2528 | return ret; | |
2529 | } | |
2530 | ||
2531 | return 0; | |
2532 | } | |
2533 | ||
cebdb986 JA |
2534 | static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2535 | { | |
2536 | struct open_how __user *how; | |
2537 | const char __user *fname; | |
2538 | size_t len; | |
2539 | int ret; | |
2540 | ||
2541 | if (sqe->ioprio || sqe->buf_index) | |
2542 | return -EINVAL; | |
2543 | ||
2544 | req->open.dfd = READ_ONCE(sqe->fd); | |
2545 | fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); | |
2546 | how = u64_to_user_ptr(READ_ONCE(sqe->addr2)); | |
2547 | len = READ_ONCE(sqe->len); | |
2548 | ||
2549 | if (len < OPEN_HOW_SIZE_VER0) | |
2550 | return -EINVAL; | |
2551 | ||
2552 | ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how, | |
2553 | len); | |
2554 | if (ret) | |
2555 | return ret; | |
2556 | ||
2557 | if (!(req->open.how.flags & O_PATH) && force_o_largefile()) | |
2558 | req->open.how.flags |= O_LARGEFILE; | |
2559 | ||
2560 | req->open.filename = getname(fname); | |
2561 | if (IS_ERR(req->open.filename)) { | |
2562 | ret = PTR_ERR(req->open.filename); | |
2563 | req->open.filename = NULL; | |
2564 | return ret; | |
2565 | } | |
2566 | ||
2567 | return 0; | |
2568 | } | |
2569 | ||
2570 | static int io_openat2(struct io_kiocb *req, struct io_kiocb **nxt, | |
2571 | bool force_nonblock) | |
15b71abe JA |
2572 | { |
2573 | struct open_flags op; | |
15b71abe JA |
2574 | struct file *file; |
2575 | int ret; | |
2576 | ||
2577 | if (force_nonblock) { | |
2578 | req->work.flags |= IO_WQ_WORK_NEEDS_FILES; | |
2579 | return -EAGAIN; | |
2580 | } | |
2581 | ||
cebdb986 | 2582 | ret = build_open_flags(&req->open.how, &op); |
15b71abe JA |
2583 | if (ret) |
2584 | goto err; | |
2585 | ||
cebdb986 | 2586 | ret = get_unused_fd_flags(req->open.how.flags); |
15b71abe JA |
2587 | if (ret < 0) |
2588 | goto err; | |
2589 | ||
2590 | file = do_filp_open(req->open.dfd, req->open.filename, &op); | |
2591 | if (IS_ERR(file)) { | |
2592 | put_unused_fd(ret); | |
2593 | ret = PTR_ERR(file); | |
2594 | } else { | |
2595 | fsnotify_open(file); | |
2596 | fd_install(ret, file); | |
2597 | } | |
2598 | err: | |
2599 | putname(req->open.filename); | |
2600 | if (ret < 0) | |
2601 | req_set_fail_links(req); | |
2602 | io_cqring_add_event(req, ret); | |
2603 | io_put_req_find_next(req, nxt); | |
2604 | return 0; | |
2605 | } | |
2606 | ||
cebdb986 JA |
2607 | static int io_openat(struct io_kiocb *req, struct io_kiocb **nxt, |
2608 | bool force_nonblock) | |
2609 | { | |
2610 | req->open.how = build_open_how(req->open.how.flags, req->open.how.mode); | |
2611 | return io_openat2(req, nxt, force_nonblock); | |
2612 | } | |
2613 | ||
c1ca757b JA |
2614 | static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2615 | { | |
2616 | #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU) | |
2617 | if (sqe->ioprio || sqe->buf_index || sqe->off) | |
2618 | return -EINVAL; | |
2619 | ||
2620 | req->madvise.addr = READ_ONCE(sqe->addr); | |
2621 | req->madvise.len = READ_ONCE(sqe->len); | |
2622 | req->madvise.advice = READ_ONCE(sqe->fadvise_advice); | |
2623 | return 0; | |
2624 | #else | |
2625 | return -EOPNOTSUPP; | |
2626 | #endif | |
2627 | } | |
2628 | ||
2629 | static int io_madvise(struct io_kiocb *req, struct io_kiocb **nxt, | |
2630 | bool force_nonblock) | |
2631 | { | |
2632 | #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU) | |
2633 | struct io_madvise *ma = &req->madvise; | |
2634 | int ret; | |
2635 | ||
2636 | if (force_nonblock) | |
2637 | return -EAGAIN; | |
2638 | ||
2639 | ret = do_madvise(ma->addr, ma->len, ma->advice); | |
2640 | if (ret < 0) | |
2641 | req_set_fail_links(req); | |
2642 | io_cqring_add_event(req, ret); | |
2643 | io_put_req_find_next(req, nxt); | |
2644 | return 0; | |
2645 | #else | |
2646 | return -EOPNOTSUPP; | |
2647 | #endif | |
2648 | } | |
2649 | ||
4840e418 JA |
2650 | static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2651 | { | |
2652 | if (sqe->ioprio || sqe->buf_index || sqe->addr) | |
2653 | return -EINVAL; | |
2654 | ||
2655 | req->fadvise.offset = READ_ONCE(sqe->off); | |
2656 | req->fadvise.len = READ_ONCE(sqe->len); | |
2657 | req->fadvise.advice = READ_ONCE(sqe->fadvise_advice); | |
2658 | return 0; | |
2659 | } | |
2660 | ||
2661 | static int io_fadvise(struct io_kiocb *req, struct io_kiocb **nxt, | |
2662 | bool force_nonblock) | |
2663 | { | |
2664 | struct io_fadvise *fa = &req->fadvise; | |
2665 | int ret; | |
2666 | ||
2667 | /* DONTNEED may block, others _should_ not */ | |
2668 | if (fa->advice == POSIX_FADV_DONTNEED && force_nonblock) | |
2669 | return -EAGAIN; | |
2670 | ||
2671 | ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice); | |
2672 | if (ret < 0) | |
2673 | req_set_fail_links(req); | |
2674 | io_cqring_add_event(req, ret); | |
2675 | io_put_req_find_next(req, nxt); | |
2676 | return 0; | |
2677 | } | |
2678 | ||
eddc7ef5 JA |
2679 | static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2680 | { | |
f8748881 | 2681 | const char __user *fname; |
eddc7ef5 JA |
2682 | unsigned lookup_flags; |
2683 | int ret; | |
2684 | ||
2685 | if (sqe->ioprio || sqe->buf_index) | |
2686 | return -EINVAL; | |
2687 | ||
2688 | req->open.dfd = READ_ONCE(sqe->fd); | |
2689 | req->open.mask = READ_ONCE(sqe->len); | |
f8748881 | 2690 | fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); |
eddc7ef5 | 2691 | req->open.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2)); |
c12cedf2 | 2692 | req->open.how.flags = READ_ONCE(sqe->statx_flags); |
eddc7ef5 | 2693 | |
c12cedf2 | 2694 | if (vfs_stat_set_lookup_flags(&lookup_flags, req->open.how.flags)) |
eddc7ef5 JA |
2695 | return -EINVAL; |
2696 | ||
f8748881 | 2697 | req->open.filename = getname_flags(fname, lookup_flags, NULL); |
eddc7ef5 JA |
2698 | if (IS_ERR(req->open.filename)) { |
2699 | ret = PTR_ERR(req->open.filename); | |
2700 | req->open.filename = NULL; | |
2701 | return ret; | |
2702 | } | |
2703 | ||
2704 | return 0; | |
2705 | } | |
2706 | ||
2707 | static int io_statx(struct io_kiocb *req, struct io_kiocb **nxt, | |
2708 | bool force_nonblock) | |
2709 | { | |
2710 | struct io_open *ctx = &req->open; | |
2711 | unsigned lookup_flags; | |
2712 | struct path path; | |
2713 | struct kstat stat; | |
2714 | int ret; | |
2715 | ||
2716 | if (force_nonblock) | |
2717 | return -EAGAIN; | |
2718 | ||
c12cedf2 | 2719 | if (vfs_stat_set_lookup_flags(&lookup_flags, ctx->how.flags)) |
eddc7ef5 JA |
2720 | return -EINVAL; |
2721 | ||
2722 | retry: | |
2723 | /* filename_lookup() drops it, keep a reference */ | |
2724 | ctx->filename->refcnt++; | |
2725 | ||
2726 | ret = filename_lookup(ctx->dfd, ctx->filename, lookup_flags, &path, | |
2727 | NULL); | |
2728 | if (ret) | |
2729 | goto err; | |
2730 | ||
c12cedf2 | 2731 | ret = vfs_getattr(&path, &stat, ctx->mask, ctx->how.flags); |
eddc7ef5 JA |
2732 | path_put(&path); |
2733 | if (retry_estale(ret, lookup_flags)) { | |
2734 | lookup_flags |= LOOKUP_REVAL; | |
2735 | goto retry; | |
2736 | } | |
2737 | if (!ret) | |
2738 | ret = cp_statx(&stat, ctx->buffer); | |
2739 | err: | |
2740 | putname(ctx->filename); | |
2741 | if (ret < 0) | |
2742 | req_set_fail_links(req); | |
2743 | io_cqring_add_event(req, ret); | |
2744 | io_put_req_find_next(req, nxt); | |
2745 | return 0; | |
2746 | } | |
2747 | ||
b5dba59e JA |
2748 | static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2749 | { | |
2750 | /* | |
2751 | * If we queue this for async, it must not be cancellable. That would | |
2752 | * leave the 'file' in an undeterminate state. | |
2753 | */ | |
2754 | req->work.flags |= IO_WQ_WORK_NO_CANCEL; | |
2755 | ||
2756 | if (sqe->ioprio || sqe->off || sqe->addr || sqe->len || | |
2757 | sqe->rw_flags || sqe->buf_index) | |
2758 | return -EINVAL; | |
2759 | if (sqe->flags & IOSQE_FIXED_FILE) | |
2760 | return -EINVAL; | |
2761 | ||
2762 | req->close.fd = READ_ONCE(sqe->fd); | |
2763 | if (req->file->f_op == &io_uring_fops || | |
b14cca0c | 2764 | req->close.fd == req->ctx->ring_fd) |
b5dba59e JA |
2765 | return -EBADF; |
2766 | ||
2767 | return 0; | |
2768 | } | |
2769 | ||
2770 | static void io_close_finish(struct io_wq_work **workptr) | |
2771 | { | |
2772 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2773 | struct io_kiocb *nxt = NULL; | |
2774 | ||
2775 | /* Invoked with files, we need to do the close */ | |
2776 | if (req->work.files) { | |
2777 | int ret; | |
2778 | ||
2779 | ret = filp_close(req->close.put_file, req->work.files); | |
2780 | if (ret < 0) { | |
2781 | req_set_fail_links(req); | |
2782 | } | |
2783 | io_cqring_add_event(req, ret); | |
2784 | } | |
2785 | ||
2786 | fput(req->close.put_file); | |
2787 | ||
2788 | /* we bypassed the re-issue, drop the submission reference */ | |
2789 | io_put_req(req); | |
2790 | io_put_req_find_next(req, &nxt); | |
2791 | if (nxt) | |
2792 | io_wq_assign_next(workptr, nxt); | |
2793 | } | |
2794 | ||
2795 | static int io_close(struct io_kiocb *req, struct io_kiocb **nxt, | |
2796 | bool force_nonblock) | |
2797 | { | |
2798 | int ret; | |
2799 | ||
2800 | req->close.put_file = NULL; | |
2801 | ret = __close_fd_get_file(req->close.fd, &req->close.put_file); | |
2802 | if (ret < 0) | |
2803 | return ret; | |
2804 | ||
2805 | /* if the file has a flush method, be safe and punt to async */ | |
2806 | if (req->close.put_file->f_op->flush && !io_wq_current_is_worker()) { | |
2807 | req->work.flags |= IO_WQ_WORK_NEEDS_FILES; | |
2808 | goto eagain; | |
2809 | } | |
2810 | ||
2811 | /* | |
2812 | * No ->flush(), safely close from here and just punt the | |
2813 | * fput() to async context. | |
2814 | */ | |
2815 | ret = filp_close(req->close.put_file, current->files); | |
2816 | ||
2817 | if (ret < 0) | |
2818 | req_set_fail_links(req); | |
2819 | io_cqring_add_event(req, ret); | |
2820 | ||
2821 | if (io_wq_current_is_worker()) { | |
2822 | struct io_wq_work *old_work, *work; | |
2823 | ||
2824 | old_work = work = &req->work; | |
2825 | io_close_finish(&work); | |
2826 | if (work && work != old_work) | |
2827 | *nxt = container_of(work, struct io_kiocb, work); | |
2828 | return 0; | |
2829 | } | |
2830 | ||
2831 | eagain: | |
2832 | req->work.func = io_close_finish; | |
2833 | return -EAGAIN; | |
2834 | } | |
2835 | ||
3529d8c2 | 2836 | static int io_prep_sfr(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
5d17b4a4 JA |
2837 | { |
2838 | struct io_ring_ctx *ctx = req->ctx; | |
5d17b4a4 JA |
2839 | |
2840 | if (!req->file) | |
2841 | return -EBADF; | |
5d17b4a4 JA |
2842 | |
2843 | if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) | |
2844 | return -EINVAL; | |
2845 | if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index)) | |
2846 | return -EINVAL; | |
2847 | ||
8ed8d3c3 JA |
2848 | req->sync.off = READ_ONCE(sqe->off); |
2849 | req->sync.len = READ_ONCE(sqe->len); | |
2850 | req->sync.flags = READ_ONCE(sqe->sync_range_flags); | |
8ed8d3c3 JA |
2851 | return 0; |
2852 | } | |
2853 | ||
2854 | static void io_sync_file_range_finish(struct io_wq_work **workptr) | |
2855 | { | |
2856 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2857 | struct io_kiocb *nxt = NULL; | |
2858 | int ret; | |
2859 | ||
2860 | if (io_req_cancelled(req)) | |
2861 | return; | |
2862 | ||
9adbd45d | 2863 | ret = sync_file_range(req->file, req->sync.off, req->sync.len, |
8ed8d3c3 JA |
2864 | req->sync.flags); |
2865 | if (ret < 0) | |
2866 | req_set_fail_links(req); | |
2867 | io_cqring_add_event(req, ret); | |
2868 | io_put_req_find_next(req, &nxt); | |
2869 | if (nxt) | |
78912934 | 2870 | io_wq_assign_next(workptr, nxt); |
5d17b4a4 JA |
2871 | } |
2872 | ||
fc4df999 | 2873 | static int io_sync_file_range(struct io_kiocb *req, struct io_kiocb **nxt, |
5d17b4a4 JA |
2874 | bool force_nonblock) |
2875 | { | |
8ed8d3c3 | 2876 | struct io_wq_work *work, *old_work; |
5d17b4a4 JA |
2877 | |
2878 | /* sync_file_range always requires a blocking context */ | |
8ed8d3c3 JA |
2879 | if (force_nonblock) { |
2880 | io_put_req(req); | |
2881 | req->work.func = io_sync_file_range_finish; | |
5d17b4a4 | 2882 | return -EAGAIN; |
8ed8d3c3 | 2883 | } |
5d17b4a4 | 2884 | |
8ed8d3c3 JA |
2885 | work = old_work = &req->work; |
2886 | io_sync_file_range_finish(&work); | |
2887 | if (work && work != old_work) | |
2888 | *nxt = container_of(work, struct io_kiocb, work); | |
5d17b4a4 JA |
2889 | return 0; |
2890 | } | |
2891 | ||
b7bb4f7d JA |
2892 | #if defined(CONFIG_NET) |
2893 | static void io_sendrecv_async(struct io_wq_work **workptr) | |
2894 | { | |
2895 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2896 | struct iovec *iov = NULL; | |
2897 | ||
2898 | if (req->io->rw.iov != req->io->rw.fast_iov) | |
2899 | iov = req->io->msg.iov; | |
2900 | io_wq_submit_work(workptr); | |
2901 | kfree(iov); | |
2902 | } | |
2903 | #endif | |
2904 | ||
3529d8c2 | 2905 | static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
03b1230c | 2906 | { |
0fa03c62 | 2907 | #if defined(CONFIG_NET) |
e47293fd | 2908 | struct io_sr_msg *sr = &req->sr_msg; |
3529d8c2 | 2909 | struct io_async_ctx *io = req->io; |
03b1230c | 2910 | |
e47293fd JA |
2911 | sr->msg_flags = READ_ONCE(sqe->msg_flags); |
2912 | sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr)); | |
fddaface | 2913 | sr->len = READ_ONCE(sqe->len); |
3529d8c2 | 2914 | |
fddaface | 2915 | if (!io || req->opcode == IORING_OP_SEND) |
3529d8c2 JA |
2916 | return 0; |
2917 | ||
d9688565 | 2918 | io->msg.iov = io->msg.fast_iov; |
3529d8c2 | 2919 | return sendmsg_copy_msghdr(&io->msg.msg, sr->msg, sr->msg_flags, |
e47293fd | 2920 | &io->msg.iov); |
03b1230c | 2921 | #else |
e47293fd | 2922 | return -EOPNOTSUPP; |
03b1230c JA |
2923 | #endif |
2924 | } | |
2925 | ||
fc4df999 JA |
2926 | static int io_sendmsg(struct io_kiocb *req, struct io_kiocb **nxt, |
2927 | bool force_nonblock) | |
aa1fa28f | 2928 | { |
03b1230c | 2929 | #if defined(CONFIG_NET) |
0b416c3e | 2930 | struct io_async_msghdr *kmsg = NULL; |
0fa03c62 JA |
2931 | struct socket *sock; |
2932 | int ret; | |
2933 | ||
2934 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) | |
2935 | return -EINVAL; | |
2936 | ||
2937 | sock = sock_from_file(req->file, &ret); | |
2938 | if (sock) { | |
b7bb4f7d | 2939 | struct io_async_ctx io; |
03b1230c | 2940 | struct sockaddr_storage addr; |
0fa03c62 JA |
2941 | unsigned flags; |
2942 | ||
03b1230c | 2943 | if (req->io) { |
0b416c3e JA |
2944 | kmsg = &req->io->msg; |
2945 | kmsg->msg.msg_name = &addr; | |
2946 | /* if iov is set, it's allocated already */ | |
2947 | if (!kmsg->iov) | |
2948 | kmsg->iov = kmsg->fast_iov; | |
2949 | kmsg->msg.msg_iter.iov = kmsg->iov; | |
03b1230c | 2950 | } else { |
3529d8c2 JA |
2951 | struct io_sr_msg *sr = &req->sr_msg; |
2952 | ||
0b416c3e JA |
2953 | kmsg = &io.msg; |
2954 | kmsg->msg.msg_name = &addr; | |
3529d8c2 JA |
2955 | |
2956 | io.msg.iov = io.msg.fast_iov; | |
2957 | ret = sendmsg_copy_msghdr(&io.msg.msg, sr->msg, | |
2958 | sr->msg_flags, &io.msg.iov); | |
03b1230c | 2959 | if (ret) |
3529d8c2 | 2960 | return ret; |
03b1230c | 2961 | } |
0fa03c62 | 2962 | |
e47293fd JA |
2963 | flags = req->sr_msg.msg_flags; |
2964 | if (flags & MSG_DONTWAIT) | |
2965 | req->flags |= REQ_F_NOWAIT; | |
2966 | else if (force_nonblock) | |
2967 | flags |= MSG_DONTWAIT; | |
2968 | ||
0b416c3e | 2969 | ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags); |
03b1230c | 2970 | if (force_nonblock && ret == -EAGAIN) { |
b7bb4f7d JA |
2971 | if (req->io) |
2972 | return -EAGAIN; | |
2973 | if (io_alloc_async_ctx(req)) | |
2974 | return -ENOMEM; | |
2975 | memcpy(&req->io->msg, &io.msg, sizeof(io.msg)); | |
2976 | req->work.func = io_sendrecv_async; | |
0b416c3e | 2977 | return -EAGAIN; |
03b1230c | 2978 | } |
441cdbd5 JA |
2979 | if (ret == -ERESTARTSYS) |
2980 | ret = -EINTR; | |
0fa03c62 JA |
2981 | } |
2982 | ||
b7bb4f7d | 2983 | if (!io_wq_current_is_worker() && kmsg && kmsg->iov != kmsg->fast_iov) |
0b416c3e | 2984 | kfree(kmsg->iov); |
78e19bbe | 2985 | io_cqring_add_event(req, ret); |
4e88d6e7 JA |
2986 | if (ret < 0) |
2987 | req_set_fail_links(req); | |
ec9c02ad | 2988 | io_put_req_find_next(req, nxt); |
5d17b4a4 | 2989 | return 0; |
03b1230c JA |
2990 | #else |
2991 | return -EOPNOTSUPP; | |
aa1fa28f | 2992 | #endif |
03b1230c | 2993 | } |
aa1fa28f | 2994 | |
fddaface JA |
2995 | static int io_send(struct io_kiocb *req, struct io_kiocb **nxt, |
2996 | bool force_nonblock) | |
2997 | { | |
2998 | #if defined(CONFIG_NET) | |
2999 | struct socket *sock; | |
3000 | int ret; | |
3001 | ||
3002 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) | |
3003 | return -EINVAL; | |
3004 | ||
3005 | sock = sock_from_file(req->file, &ret); | |
3006 | if (sock) { | |
3007 | struct io_sr_msg *sr = &req->sr_msg; | |
3008 | struct msghdr msg; | |
3009 | struct iovec iov; | |
3010 | unsigned flags; | |
3011 | ||
3012 | ret = import_single_range(WRITE, sr->buf, sr->len, &iov, | |
3013 | &msg.msg_iter); | |
3014 | if (ret) | |
3015 | return ret; | |
3016 | ||
3017 | msg.msg_name = NULL; | |
3018 | msg.msg_control = NULL; | |
3019 | msg.msg_controllen = 0; | |
3020 | msg.msg_namelen = 0; | |
3021 | ||
3022 | flags = req->sr_msg.msg_flags; | |
3023 | if (flags & MSG_DONTWAIT) | |
3024 | req->flags |= REQ_F_NOWAIT; | |
3025 | else if (force_nonblock) | |
3026 | flags |= MSG_DONTWAIT; | |
3027 | ||
3028 | ret = __sys_sendmsg_sock(sock, &msg, flags); | |
3029 | if (force_nonblock && ret == -EAGAIN) | |
3030 | return -EAGAIN; | |
3031 | if (ret == -ERESTARTSYS) | |
3032 | ret = -EINTR; | |
3033 | } | |
3034 | ||
3035 | io_cqring_add_event(req, ret); | |
3036 | if (ret < 0) | |
3037 | req_set_fail_links(req); | |
3038 | io_put_req_find_next(req, nxt); | |
3039 | return 0; | |
3040 | #else | |
3041 | return -EOPNOTSUPP; | |
3042 | #endif | |
3043 | } | |
3044 | ||
3529d8c2 JA |
3045 | static int io_recvmsg_prep(struct io_kiocb *req, |
3046 | const struct io_uring_sqe *sqe) | |
aa1fa28f JA |
3047 | { |
3048 | #if defined(CONFIG_NET) | |
e47293fd | 3049 | struct io_sr_msg *sr = &req->sr_msg; |
3529d8c2 JA |
3050 | struct io_async_ctx *io = req->io; |
3051 | ||
3052 | sr->msg_flags = READ_ONCE(sqe->msg_flags); | |
3053 | sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr)); | |
06b76d44 | 3054 | |
fddaface | 3055 | if (!io || req->opcode == IORING_OP_RECV) |
06b76d44 | 3056 | return 0; |
03b1230c | 3057 | |
d9688565 | 3058 | io->msg.iov = io->msg.fast_iov; |
3529d8c2 | 3059 | return recvmsg_copy_msghdr(&io->msg.msg, sr->msg, sr->msg_flags, |
e47293fd | 3060 | &io->msg.uaddr, &io->msg.iov); |
aa1fa28f | 3061 | #else |
e47293fd | 3062 | return -EOPNOTSUPP; |
aa1fa28f JA |
3063 | #endif |
3064 | } | |
3065 | ||
fc4df999 JA |
3066 | static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt, |
3067 | bool force_nonblock) | |
aa1fa28f JA |
3068 | { |
3069 | #if defined(CONFIG_NET) | |
0b416c3e | 3070 | struct io_async_msghdr *kmsg = NULL; |
03b1230c JA |
3071 | struct socket *sock; |
3072 | int ret; | |
3073 | ||
3074 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) | |
3075 | return -EINVAL; | |
3076 | ||
3077 | sock = sock_from_file(req->file, &ret); | |
3078 | if (sock) { | |
b7bb4f7d | 3079 | struct io_async_ctx io; |
03b1230c | 3080 | struct sockaddr_storage addr; |
03b1230c JA |
3081 | unsigned flags; |
3082 | ||
03b1230c | 3083 | if (req->io) { |
0b416c3e JA |
3084 | kmsg = &req->io->msg; |
3085 | kmsg->msg.msg_name = &addr; | |
3086 | /* if iov is set, it's allocated already */ | |
3087 | if (!kmsg->iov) | |
3088 | kmsg->iov = kmsg->fast_iov; | |
3089 | kmsg->msg.msg_iter.iov = kmsg->iov; | |
03b1230c | 3090 | } else { |
3529d8c2 JA |
3091 | struct io_sr_msg *sr = &req->sr_msg; |
3092 | ||
0b416c3e JA |
3093 | kmsg = &io.msg; |
3094 | kmsg->msg.msg_name = &addr; | |
3529d8c2 JA |
3095 | |
3096 | io.msg.iov = io.msg.fast_iov; | |
3097 | ret = recvmsg_copy_msghdr(&io.msg.msg, sr->msg, | |
3098 | sr->msg_flags, &io.msg.uaddr, | |
3099 | &io.msg.iov); | |
03b1230c | 3100 | if (ret) |
3529d8c2 | 3101 | return ret; |
03b1230c JA |
3102 | } |
3103 | ||
e47293fd JA |
3104 | flags = req->sr_msg.msg_flags; |
3105 | if (flags & MSG_DONTWAIT) | |
3106 | req->flags |= REQ_F_NOWAIT; | |
3107 | else if (force_nonblock) | |
3108 | flags |= MSG_DONTWAIT; | |
3109 | ||
3110 | ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.msg, | |
3111 | kmsg->uaddr, flags); | |
03b1230c | 3112 | if (force_nonblock && ret == -EAGAIN) { |
b7bb4f7d JA |
3113 | if (req->io) |
3114 | return -EAGAIN; | |
3115 | if (io_alloc_async_ctx(req)) | |
3116 | return -ENOMEM; | |
3117 | memcpy(&req->io->msg, &io.msg, sizeof(io.msg)); | |
3118 | req->work.func = io_sendrecv_async; | |
0b416c3e | 3119 | return -EAGAIN; |
03b1230c JA |
3120 | } |
3121 | if (ret == -ERESTARTSYS) | |
3122 | ret = -EINTR; | |
3123 | } | |
3124 | ||
b7bb4f7d | 3125 | if (!io_wq_current_is_worker() && kmsg && kmsg->iov != kmsg->fast_iov) |
0b416c3e | 3126 | kfree(kmsg->iov); |
03b1230c | 3127 | io_cqring_add_event(req, ret); |
4e88d6e7 JA |
3128 | if (ret < 0) |
3129 | req_set_fail_links(req); | |
03b1230c JA |
3130 | io_put_req_find_next(req, nxt); |
3131 | return 0; | |
0fa03c62 JA |
3132 | #else |
3133 | return -EOPNOTSUPP; | |
3134 | #endif | |
3135 | } | |
5d17b4a4 | 3136 | |
fddaface JA |
3137 | static int io_recv(struct io_kiocb *req, struct io_kiocb **nxt, |
3138 | bool force_nonblock) | |
3139 | { | |
3140 | #if defined(CONFIG_NET) | |
3141 | struct socket *sock; | |
3142 | int ret; | |
3143 | ||
3144 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) | |
3145 | return -EINVAL; | |
3146 | ||
3147 | sock = sock_from_file(req->file, &ret); | |
3148 | if (sock) { | |
3149 | struct io_sr_msg *sr = &req->sr_msg; | |
3150 | struct msghdr msg; | |
3151 | struct iovec iov; | |
3152 | unsigned flags; | |
3153 | ||
3154 | ret = import_single_range(READ, sr->buf, sr->len, &iov, | |
3155 | &msg.msg_iter); | |
3156 | if (ret) | |
3157 | return ret; | |
3158 | ||
3159 | msg.msg_name = NULL; | |
3160 | msg.msg_control = NULL; | |
3161 | msg.msg_controllen = 0; | |
3162 | msg.msg_namelen = 0; | |
3163 | msg.msg_iocb = NULL; | |
3164 | msg.msg_flags = 0; | |
3165 | ||
3166 | flags = req->sr_msg.msg_flags; | |
3167 | if (flags & MSG_DONTWAIT) | |
3168 | req->flags |= REQ_F_NOWAIT; | |
3169 | else if (force_nonblock) | |
3170 | flags |= MSG_DONTWAIT; | |
3171 | ||
3172 | ret = __sys_recvmsg_sock(sock, &msg, NULL, NULL, flags); | |
3173 | if (force_nonblock && ret == -EAGAIN) | |
3174 | return -EAGAIN; | |
3175 | if (ret == -ERESTARTSYS) | |
3176 | ret = -EINTR; | |
3177 | } | |
3178 | ||
3179 | io_cqring_add_event(req, ret); | |
3180 | if (ret < 0) | |
3181 | req_set_fail_links(req); | |
3182 | io_put_req_find_next(req, nxt); | |
3183 | return 0; | |
3184 | #else | |
3185 | return -EOPNOTSUPP; | |
3186 | #endif | |
3187 | } | |
3188 | ||
3189 | ||
3529d8c2 | 3190 | static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
17f2fe35 JA |
3191 | { |
3192 | #if defined(CONFIG_NET) | |
8ed8d3c3 JA |
3193 | struct io_accept *accept = &req->accept; |
3194 | ||
17f2fe35 JA |
3195 | if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) |
3196 | return -EINVAL; | |
8042d6ce | 3197 | if (sqe->ioprio || sqe->len || sqe->buf_index) |
17f2fe35 JA |
3198 | return -EINVAL; |
3199 | ||
d55e5f5b JA |
3200 | accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr)); |
3201 | accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2)); | |
8ed8d3c3 | 3202 | accept->flags = READ_ONCE(sqe->accept_flags); |
8ed8d3c3 JA |
3203 | return 0; |
3204 | #else | |
3205 | return -EOPNOTSUPP; | |
3206 | #endif | |
3207 | } | |
17f2fe35 | 3208 | |
8ed8d3c3 JA |
3209 | #if defined(CONFIG_NET) |
3210 | static int __io_accept(struct io_kiocb *req, struct io_kiocb **nxt, | |
3211 | bool force_nonblock) | |
3212 | { | |
3213 | struct io_accept *accept = &req->accept; | |
3214 | unsigned file_flags; | |
3215 | int ret; | |
3216 | ||
3217 | file_flags = force_nonblock ? O_NONBLOCK : 0; | |
3218 | ret = __sys_accept4_file(req->file, file_flags, accept->addr, | |
3219 | accept->addr_len, accept->flags); | |
3220 | if (ret == -EAGAIN && force_nonblock) | |
17f2fe35 | 3221 | return -EAGAIN; |
8e3cca12 JA |
3222 | if (ret == -ERESTARTSYS) |
3223 | ret = -EINTR; | |
4e88d6e7 JA |
3224 | if (ret < 0) |
3225 | req_set_fail_links(req); | |
78e19bbe | 3226 | io_cqring_add_event(req, ret); |
ec9c02ad | 3227 | io_put_req_find_next(req, nxt); |
17f2fe35 | 3228 | return 0; |
8ed8d3c3 JA |
3229 | } |
3230 | ||
3231 | static void io_accept_finish(struct io_wq_work **workptr) | |
3232 | { | |
3233 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
3234 | struct io_kiocb *nxt = NULL; | |
3235 | ||
3236 | if (io_req_cancelled(req)) | |
3237 | return; | |
3238 | __io_accept(req, &nxt, false); | |
3239 | if (nxt) | |
78912934 | 3240 | io_wq_assign_next(workptr, nxt); |
8ed8d3c3 JA |
3241 | } |
3242 | #endif | |
3243 | ||
3244 | static int io_accept(struct io_kiocb *req, struct io_kiocb **nxt, | |
3245 | bool force_nonblock) | |
3246 | { | |
3247 | #if defined(CONFIG_NET) | |
3248 | int ret; | |
3249 | ||
8ed8d3c3 JA |
3250 | ret = __io_accept(req, nxt, force_nonblock); |
3251 | if (ret == -EAGAIN && force_nonblock) { | |
3252 | req->work.func = io_accept_finish; | |
3253 | req->work.flags |= IO_WQ_WORK_NEEDS_FILES; | |
3254 | io_put_req(req); | |
3255 | return -EAGAIN; | |
3256 | } | |
3257 | return 0; | |
0fa03c62 JA |
3258 | #else |
3259 | return -EOPNOTSUPP; | |
3260 | #endif | |
3261 | } | |
5d17b4a4 | 3262 | |
3529d8c2 | 3263 | static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
f499a021 JA |
3264 | { |
3265 | #if defined(CONFIG_NET) | |
3529d8c2 JA |
3266 | struct io_connect *conn = &req->connect; |
3267 | struct io_async_ctx *io = req->io; | |
f499a021 | 3268 | |
3fbb51c1 JA |
3269 | if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) |
3270 | return -EINVAL; | |
3271 | if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags) | |
3272 | return -EINVAL; | |
3273 | ||
3529d8c2 JA |
3274 | conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr)); |
3275 | conn->addr_len = READ_ONCE(sqe->addr2); | |
3276 | ||
3277 | if (!io) | |
3278 | return 0; | |
3279 | ||
3280 | return move_addr_to_kernel(conn->addr, conn->addr_len, | |
3fbb51c1 | 3281 | &io->connect.address); |
f499a021 | 3282 | #else |
3fbb51c1 | 3283 | return -EOPNOTSUPP; |
f499a021 JA |
3284 | #endif |
3285 | } | |
3286 | ||
fc4df999 JA |
3287 | static int io_connect(struct io_kiocb *req, struct io_kiocb **nxt, |
3288 | bool force_nonblock) | |
f8e85cf2 JA |
3289 | { |
3290 | #if defined(CONFIG_NET) | |
f499a021 | 3291 | struct io_async_ctx __io, *io; |
f8e85cf2 | 3292 | unsigned file_flags; |
3fbb51c1 | 3293 | int ret; |
f8e85cf2 | 3294 | |
f499a021 JA |
3295 | if (req->io) { |
3296 | io = req->io; | |
3297 | } else { | |
3529d8c2 JA |
3298 | ret = move_addr_to_kernel(req->connect.addr, |
3299 | req->connect.addr_len, | |
3300 | &__io.connect.address); | |
f499a021 JA |
3301 | if (ret) |
3302 | goto out; | |
3303 | io = &__io; | |
3304 | } | |
3305 | ||
3fbb51c1 JA |
3306 | file_flags = force_nonblock ? O_NONBLOCK : 0; |
3307 | ||
3308 | ret = __sys_connect_file(req->file, &io->connect.address, | |
3309 | req->connect.addr_len, file_flags); | |
87f80d62 | 3310 | if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) { |
b7bb4f7d JA |
3311 | if (req->io) |
3312 | return -EAGAIN; | |
3313 | if (io_alloc_async_ctx(req)) { | |
f499a021 JA |
3314 | ret = -ENOMEM; |
3315 | goto out; | |
3316 | } | |
b7bb4f7d | 3317 | memcpy(&req->io->connect, &__io.connect, sizeof(__io.connect)); |
f8e85cf2 | 3318 | return -EAGAIN; |
f499a021 | 3319 | } |
f8e85cf2 JA |
3320 | if (ret == -ERESTARTSYS) |
3321 | ret = -EINTR; | |
f499a021 | 3322 | out: |
4e88d6e7 JA |
3323 | if (ret < 0) |
3324 | req_set_fail_links(req); | |
f8e85cf2 JA |
3325 | io_cqring_add_event(req, ret); |
3326 | io_put_req_find_next(req, nxt); | |
3327 | return 0; | |
3328 | #else | |
3329 | return -EOPNOTSUPP; | |
3330 | #endif | |
3331 | } | |
3332 | ||
221c5eb2 JA |
3333 | static void io_poll_remove_one(struct io_kiocb *req) |
3334 | { | |
3335 | struct io_poll_iocb *poll = &req->poll; | |
3336 | ||
3337 | spin_lock(&poll->head->lock); | |
3338 | WRITE_ONCE(poll->canceled, true); | |
392edb45 JA |
3339 | if (!list_empty(&poll->wait.entry)) { |
3340 | list_del_init(&poll->wait.entry); | |
a197f664 | 3341 | io_queue_async_work(req); |
221c5eb2 JA |
3342 | } |
3343 | spin_unlock(&poll->head->lock); | |
78076bb6 | 3344 | hash_del(&req->hash_node); |
221c5eb2 JA |
3345 | } |
3346 | ||
3347 | static void io_poll_remove_all(struct io_ring_ctx *ctx) | |
3348 | { | |
78076bb6 | 3349 | struct hlist_node *tmp; |
221c5eb2 | 3350 | struct io_kiocb *req; |
78076bb6 | 3351 | int i; |
221c5eb2 JA |
3352 | |
3353 | spin_lock_irq(&ctx->completion_lock); | |
78076bb6 JA |
3354 | for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) { |
3355 | struct hlist_head *list; | |
3356 | ||
3357 | list = &ctx->cancel_hash[i]; | |
3358 | hlist_for_each_entry_safe(req, tmp, list, hash_node) | |
3359 | io_poll_remove_one(req); | |
221c5eb2 JA |
3360 | } |
3361 | spin_unlock_irq(&ctx->completion_lock); | |
3362 | } | |
3363 | ||
47f46768 JA |
3364 | static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr) |
3365 | { | |
78076bb6 | 3366 | struct hlist_head *list; |
47f46768 JA |
3367 | struct io_kiocb *req; |
3368 | ||
78076bb6 JA |
3369 | list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)]; |
3370 | hlist_for_each_entry(req, list, hash_node) { | |
3371 | if (sqe_addr == req->user_data) { | |
eac406c6 JA |
3372 | io_poll_remove_one(req); |
3373 | return 0; | |
3374 | } | |
47f46768 JA |
3375 | } |
3376 | ||
3377 | return -ENOENT; | |
3378 | } | |
3379 | ||
3529d8c2 JA |
3380 | static int io_poll_remove_prep(struct io_kiocb *req, |
3381 | const struct io_uring_sqe *sqe) | |
0969e783 | 3382 | { |
0969e783 JA |
3383 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) |
3384 | return -EINVAL; | |
3385 | if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index || | |
3386 | sqe->poll_events) | |
3387 | return -EINVAL; | |
3388 | ||
3389 | req->poll.addr = READ_ONCE(sqe->addr); | |
0969e783 JA |
3390 | return 0; |
3391 | } | |
3392 | ||
221c5eb2 JA |
3393 | /* |
3394 | * Find a running poll command that matches one specified in sqe->addr, | |
3395 | * and remove it if found. | |
3396 | */ | |
fc4df999 | 3397 | static int io_poll_remove(struct io_kiocb *req) |
221c5eb2 JA |
3398 | { |
3399 | struct io_ring_ctx *ctx = req->ctx; | |
0969e783 | 3400 | u64 addr; |
47f46768 | 3401 | int ret; |
221c5eb2 | 3402 | |
0969e783 | 3403 | addr = req->poll.addr; |
221c5eb2 | 3404 | spin_lock_irq(&ctx->completion_lock); |
0969e783 | 3405 | ret = io_poll_cancel(ctx, addr); |
221c5eb2 JA |
3406 | spin_unlock_irq(&ctx->completion_lock); |
3407 | ||
78e19bbe | 3408 | io_cqring_add_event(req, ret); |
4e88d6e7 JA |
3409 | if (ret < 0) |
3410 | req_set_fail_links(req); | |
e65ef56d | 3411 | io_put_req(req); |
221c5eb2 JA |
3412 | return 0; |
3413 | } | |
3414 | ||
b0dd8a41 | 3415 | static void io_poll_complete(struct io_kiocb *req, __poll_t mask, int error) |
221c5eb2 | 3416 | { |
a197f664 JL |
3417 | struct io_ring_ctx *ctx = req->ctx; |
3418 | ||
8c838788 | 3419 | req->poll.done = true; |
b0dd8a41 JA |
3420 | if (error) |
3421 | io_cqring_fill_event(req, error); | |
3422 | else | |
3423 | io_cqring_fill_event(req, mangle_poll(mask)); | |
8c838788 | 3424 | io_commit_cqring(ctx); |
221c5eb2 JA |
3425 | } |
3426 | ||
561fb04a | 3427 | static void io_poll_complete_work(struct io_wq_work **workptr) |
221c5eb2 | 3428 | { |
561fb04a | 3429 | struct io_wq_work *work = *workptr; |
221c5eb2 JA |
3430 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); |
3431 | struct io_poll_iocb *poll = &req->poll; | |
3432 | struct poll_table_struct pt = { ._key = poll->events }; | |
3433 | struct io_ring_ctx *ctx = req->ctx; | |
89723d0b | 3434 | struct io_kiocb *nxt = NULL; |
221c5eb2 | 3435 | __poll_t mask = 0; |
b0dd8a41 | 3436 | int ret = 0; |
221c5eb2 | 3437 | |
b0dd8a41 | 3438 | if (work->flags & IO_WQ_WORK_CANCEL) { |
561fb04a | 3439 | WRITE_ONCE(poll->canceled, true); |
b0dd8a41 JA |
3440 | ret = -ECANCELED; |
3441 | } else if (READ_ONCE(poll->canceled)) { | |
3442 | ret = -ECANCELED; | |
3443 | } | |
561fb04a | 3444 | |
b0dd8a41 | 3445 | if (ret != -ECANCELED) |
221c5eb2 JA |
3446 | mask = vfs_poll(poll->file, &pt) & poll->events; |
3447 | ||
3448 | /* | |
3449 | * Note that ->ki_cancel callers also delete iocb from active_reqs after | |
3450 | * calling ->ki_cancel. We need the ctx_lock roundtrip here to | |
3451 | * synchronize with them. In the cancellation case the list_del_init | |
3452 | * itself is not actually needed, but harmless so we keep it in to | |
3453 | * avoid further branches in the fast path. | |
3454 | */ | |
3455 | spin_lock_irq(&ctx->completion_lock); | |
b0dd8a41 | 3456 | if (!mask && ret != -ECANCELED) { |
392edb45 | 3457 | add_wait_queue(poll->head, &poll->wait); |
221c5eb2 JA |
3458 | spin_unlock_irq(&ctx->completion_lock); |
3459 | return; | |
3460 | } | |
78076bb6 | 3461 | hash_del(&req->hash_node); |
b0dd8a41 | 3462 | io_poll_complete(req, mask, ret); |
221c5eb2 JA |
3463 | spin_unlock_irq(&ctx->completion_lock); |
3464 | ||
8c838788 | 3465 | io_cqring_ev_posted(ctx); |
89723d0b | 3466 | |
4e88d6e7 JA |
3467 | if (ret < 0) |
3468 | req_set_fail_links(req); | |
ec9c02ad | 3469 | io_put_req_find_next(req, &nxt); |
89723d0b | 3470 | if (nxt) |
78912934 | 3471 | io_wq_assign_next(workptr, nxt); |
221c5eb2 JA |
3472 | } |
3473 | ||
e94f141b JA |
3474 | static void __io_poll_flush(struct io_ring_ctx *ctx, struct llist_node *nodes) |
3475 | { | |
e94f141b | 3476 | struct io_kiocb *req, *tmp; |
8237e045 | 3477 | struct req_batch rb; |
e94f141b | 3478 | |
c6ca97b3 | 3479 | rb.to_free = rb.need_iter = 0; |
e94f141b JA |
3480 | spin_lock_irq(&ctx->completion_lock); |
3481 | llist_for_each_entry_safe(req, tmp, nodes, llist_node) { | |
3482 | hash_del(&req->hash_node); | |
3483 | io_poll_complete(req, req->result, 0); | |
3484 | ||
8237e045 JA |
3485 | if (refcount_dec_and_test(&req->refs) && |
3486 | !io_req_multi_free(&rb, req)) { | |
3487 | req->flags |= REQ_F_COMP_LOCKED; | |
3488 | io_free_req(req); | |
e94f141b JA |
3489 | } |
3490 | } | |
3491 | spin_unlock_irq(&ctx->completion_lock); | |
3492 | ||
3493 | io_cqring_ev_posted(ctx); | |
8237e045 | 3494 | io_free_req_many(ctx, &rb); |
e94f141b JA |
3495 | } |
3496 | ||
3497 | static void io_poll_flush(struct io_wq_work **workptr) | |
3498 | { | |
3499 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
3500 | struct llist_node *nodes; | |
3501 | ||
3502 | nodes = llist_del_all(&req->ctx->poll_llist); | |
3503 | if (nodes) | |
3504 | __io_poll_flush(req->ctx, nodes); | |
3505 | } | |
3506 | ||
221c5eb2 JA |
3507 | static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, |
3508 | void *key) | |
3509 | { | |
e944475e | 3510 | struct io_poll_iocb *poll = wait->private; |
221c5eb2 JA |
3511 | struct io_kiocb *req = container_of(poll, struct io_kiocb, poll); |
3512 | struct io_ring_ctx *ctx = req->ctx; | |
3513 | __poll_t mask = key_to_poll(key); | |
221c5eb2 JA |
3514 | |
3515 | /* for instances that support it check for an event match first: */ | |
8c838788 JA |
3516 | if (mask && !(mask & poll->events)) |
3517 | return 0; | |
221c5eb2 | 3518 | |
392edb45 | 3519 | list_del_init(&poll->wait.entry); |
221c5eb2 | 3520 | |
7c9e7f0f JA |
3521 | /* |
3522 | * Run completion inline if we can. We're using trylock here because | |
3523 | * we are violating the completion_lock -> poll wq lock ordering. | |
3524 | * If we have a link timeout we're going to need the completion_lock | |
3525 | * for finalizing the request, mark us as having grabbed that already. | |
3526 | */ | |
e94f141b JA |
3527 | if (mask) { |
3528 | unsigned long flags; | |
221c5eb2 | 3529 | |
e94f141b JA |
3530 | if (llist_empty(&ctx->poll_llist) && |
3531 | spin_trylock_irqsave(&ctx->completion_lock, flags)) { | |
3532 | hash_del(&req->hash_node); | |
3533 | io_poll_complete(req, mask, 0); | |
3534 | req->flags |= REQ_F_COMP_LOCKED; | |
3535 | io_put_req(req); | |
3536 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
3537 | ||
3538 | io_cqring_ev_posted(ctx); | |
3539 | req = NULL; | |
3540 | } else { | |
3541 | req->result = mask; | |
3542 | req->llist_node.next = NULL; | |
3543 | /* if the list wasn't empty, we're done */ | |
3544 | if (!llist_add(&req->llist_node, &ctx->poll_llist)) | |
3545 | req = NULL; | |
3546 | else | |
3547 | req->work.func = io_poll_flush; | |
3548 | } | |
221c5eb2 | 3549 | } |
e94f141b JA |
3550 | if (req) |
3551 | io_queue_async_work(req); | |
221c5eb2 | 3552 | |
221c5eb2 JA |
3553 | return 1; |
3554 | } | |
3555 | ||
3556 | struct io_poll_table { | |
3557 | struct poll_table_struct pt; | |
3558 | struct io_kiocb *req; | |
3559 | int error; | |
3560 | }; | |
3561 | ||
3562 | static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head, | |
3563 | struct poll_table_struct *p) | |
3564 | { | |
3565 | struct io_poll_table *pt = container_of(p, struct io_poll_table, pt); | |
3566 | ||
3567 | if (unlikely(pt->req->poll.head)) { | |
3568 | pt->error = -EINVAL; | |
3569 | return; | |
3570 | } | |
3571 | ||
3572 | pt->error = 0; | |
3573 | pt->req->poll.head = head; | |
392edb45 | 3574 | add_wait_queue(head, &pt->req->poll.wait); |
221c5eb2 JA |
3575 | } |
3576 | ||
eac406c6 JA |
3577 | static void io_poll_req_insert(struct io_kiocb *req) |
3578 | { | |
3579 | struct io_ring_ctx *ctx = req->ctx; | |
78076bb6 JA |
3580 | struct hlist_head *list; |
3581 | ||
3582 | list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)]; | |
3583 | hlist_add_head(&req->hash_node, list); | |
eac406c6 JA |
3584 | } |
3585 | ||
3529d8c2 | 3586 | static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
221c5eb2 JA |
3587 | { |
3588 | struct io_poll_iocb *poll = &req->poll; | |
221c5eb2 | 3589 | u16 events; |
221c5eb2 JA |
3590 | |
3591 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) | |
3592 | return -EINVAL; | |
3593 | if (sqe->addr || sqe->ioprio || sqe->off || sqe->len || sqe->buf_index) | |
3594 | return -EINVAL; | |
09bb8394 JA |
3595 | if (!poll->file) |
3596 | return -EBADF; | |
221c5eb2 | 3597 | |
221c5eb2 JA |
3598 | events = READ_ONCE(sqe->poll_events); |
3599 | poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP; | |
0969e783 JA |
3600 | return 0; |
3601 | } | |
3602 | ||
3603 | static int io_poll_add(struct io_kiocb *req, struct io_kiocb **nxt) | |
3604 | { | |
3605 | struct io_poll_iocb *poll = &req->poll; | |
3606 | struct io_ring_ctx *ctx = req->ctx; | |
3607 | struct io_poll_table ipt; | |
3608 | bool cancel = false; | |
3609 | __poll_t mask; | |
0969e783 JA |
3610 | |
3611 | INIT_IO_WORK(&req->work, io_poll_complete_work); | |
78076bb6 | 3612 | INIT_HLIST_NODE(&req->hash_node); |
221c5eb2 | 3613 | |
221c5eb2 | 3614 | poll->head = NULL; |
8c838788 | 3615 | poll->done = false; |
221c5eb2 JA |
3616 | poll->canceled = false; |
3617 | ||
3618 | ipt.pt._qproc = io_poll_queue_proc; | |
3619 | ipt.pt._key = poll->events; | |
3620 | ipt.req = req; | |
3621 | ipt.error = -EINVAL; /* same as no support for IOCB_CMD_POLL */ | |
3622 | ||
3623 | /* initialized the list so that we can do list_empty checks */ | |
392edb45 JA |
3624 | INIT_LIST_HEAD(&poll->wait.entry); |
3625 | init_waitqueue_func_entry(&poll->wait, io_poll_wake); | |
3626 | poll->wait.private = poll; | |
221c5eb2 | 3627 | |
36703247 JA |
3628 | INIT_LIST_HEAD(&req->list); |
3629 | ||
221c5eb2 | 3630 | mask = vfs_poll(poll->file, &ipt.pt) & poll->events; |
221c5eb2 JA |
3631 | |
3632 | spin_lock_irq(&ctx->completion_lock); | |
8c838788 JA |
3633 | if (likely(poll->head)) { |
3634 | spin_lock(&poll->head->lock); | |
392edb45 | 3635 | if (unlikely(list_empty(&poll->wait.entry))) { |
8c838788 JA |
3636 | if (ipt.error) |
3637 | cancel = true; | |
3638 | ipt.error = 0; | |
3639 | mask = 0; | |
3640 | } | |
3641 | if (mask || ipt.error) | |
392edb45 | 3642 | list_del_init(&poll->wait.entry); |
8c838788 JA |
3643 | else if (cancel) |
3644 | WRITE_ONCE(poll->canceled, true); | |
3645 | else if (!poll->done) /* actually waiting for an event */ | |
eac406c6 | 3646 | io_poll_req_insert(req); |
8c838788 JA |
3647 | spin_unlock(&poll->head->lock); |
3648 | } | |
3649 | if (mask) { /* no async, we'd stolen it */ | |
221c5eb2 | 3650 | ipt.error = 0; |
b0dd8a41 | 3651 | io_poll_complete(req, mask, 0); |
221c5eb2 | 3652 | } |
221c5eb2 JA |
3653 | spin_unlock_irq(&ctx->completion_lock); |
3654 | ||
8c838788 JA |
3655 | if (mask) { |
3656 | io_cqring_ev_posted(ctx); | |
ec9c02ad | 3657 | io_put_req_find_next(req, nxt); |
221c5eb2 | 3658 | } |
8c838788 | 3659 | return ipt.error; |
221c5eb2 JA |
3660 | } |
3661 | ||
5262f567 JA |
3662 | static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer) |
3663 | { | |
ad8a48ac JA |
3664 | struct io_timeout_data *data = container_of(timer, |
3665 | struct io_timeout_data, timer); | |
3666 | struct io_kiocb *req = data->req; | |
3667 | struct io_ring_ctx *ctx = req->ctx; | |
5262f567 JA |
3668 | unsigned long flags; |
3669 | ||
5262f567 JA |
3670 | atomic_inc(&ctx->cq_timeouts); |
3671 | ||
3672 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
ef03681a | 3673 | /* |
11365043 JA |
3674 | * We could be racing with timeout deletion. If the list is empty, |
3675 | * then timeout lookup already found it and will be handling it. | |
ef03681a | 3676 | */ |
842f9612 | 3677 | if (!list_empty(&req->list)) { |
11365043 | 3678 | struct io_kiocb *prev; |
5262f567 | 3679 | |
11365043 JA |
3680 | /* |
3681 | * Adjust the reqs sequence before the current one because it | |
d195a66e | 3682 | * will consume a slot in the cq_ring and the cq_tail |
11365043 JA |
3683 | * pointer will be increased, otherwise other timeout reqs may |
3684 | * return in advance without waiting for enough wait_nr. | |
3685 | */ | |
3686 | prev = req; | |
3687 | list_for_each_entry_continue_reverse(prev, &ctx->timeout_list, list) | |
3688 | prev->sequence++; | |
11365043 | 3689 | list_del_init(&req->list); |
11365043 | 3690 | } |
5262f567 | 3691 | |
78e19bbe | 3692 | io_cqring_fill_event(req, -ETIME); |
5262f567 JA |
3693 | io_commit_cqring(ctx); |
3694 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
3695 | ||
3696 | io_cqring_ev_posted(ctx); | |
4e88d6e7 | 3697 | req_set_fail_links(req); |
5262f567 JA |
3698 | io_put_req(req); |
3699 | return HRTIMER_NORESTART; | |
3700 | } | |
3701 | ||
47f46768 JA |
3702 | static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data) |
3703 | { | |
3704 | struct io_kiocb *req; | |
3705 | int ret = -ENOENT; | |
3706 | ||
3707 | list_for_each_entry(req, &ctx->timeout_list, list) { | |
3708 | if (user_data == req->user_data) { | |
3709 | list_del_init(&req->list); | |
3710 | ret = 0; | |
3711 | break; | |
3712 | } | |
3713 | } | |
3714 | ||
3715 | if (ret == -ENOENT) | |
3716 | return ret; | |
3717 | ||
2d28390a | 3718 | ret = hrtimer_try_to_cancel(&req->io->timeout.timer); |
47f46768 JA |
3719 | if (ret == -1) |
3720 | return -EALREADY; | |
3721 | ||
4e88d6e7 | 3722 | req_set_fail_links(req); |
47f46768 JA |
3723 | io_cqring_fill_event(req, -ECANCELED); |
3724 | io_put_req(req); | |
3725 | return 0; | |
3726 | } | |
3727 | ||
3529d8c2 JA |
3728 | static int io_timeout_remove_prep(struct io_kiocb *req, |
3729 | const struct io_uring_sqe *sqe) | |
b29472ee | 3730 | { |
b29472ee JA |
3731 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) |
3732 | return -EINVAL; | |
3733 | if (sqe->flags || sqe->ioprio || sqe->buf_index || sqe->len) | |
3734 | return -EINVAL; | |
3735 | ||
3736 | req->timeout.addr = READ_ONCE(sqe->addr); | |
3737 | req->timeout.flags = READ_ONCE(sqe->timeout_flags); | |
3738 | if (req->timeout.flags) | |
3739 | return -EINVAL; | |
3740 | ||
b29472ee JA |
3741 | return 0; |
3742 | } | |
3743 | ||
11365043 JA |
3744 | /* |
3745 | * Remove or update an existing timeout command | |
3746 | */ | |
fc4df999 | 3747 | static int io_timeout_remove(struct io_kiocb *req) |
11365043 JA |
3748 | { |
3749 | struct io_ring_ctx *ctx = req->ctx; | |
47f46768 | 3750 | int ret; |
11365043 | 3751 | |
11365043 | 3752 | spin_lock_irq(&ctx->completion_lock); |
b29472ee | 3753 | ret = io_timeout_cancel(ctx, req->timeout.addr); |
11365043 | 3754 | |
47f46768 | 3755 | io_cqring_fill_event(req, ret); |
11365043 JA |
3756 | io_commit_cqring(ctx); |
3757 | spin_unlock_irq(&ctx->completion_lock); | |
5262f567 | 3758 | io_cqring_ev_posted(ctx); |
4e88d6e7 JA |
3759 | if (ret < 0) |
3760 | req_set_fail_links(req); | |
ec9c02ad | 3761 | io_put_req(req); |
11365043 | 3762 | return 0; |
5262f567 JA |
3763 | } |
3764 | ||
3529d8c2 | 3765 | static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
2d28390a | 3766 | bool is_timeout_link) |
5262f567 | 3767 | { |
ad8a48ac | 3768 | struct io_timeout_data *data; |
a41525ab | 3769 | unsigned flags; |
5262f567 | 3770 | |
ad8a48ac | 3771 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) |
5262f567 | 3772 | return -EINVAL; |
ad8a48ac | 3773 | if (sqe->ioprio || sqe->buf_index || sqe->len != 1) |
a41525ab | 3774 | return -EINVAL; |
2d28390a JA |
3775 | if (sqe->off && is_timeout_link) |
3776 | return -EINVAL; | |
a41525ab JA |
3777 | flags = READ_ONCE(sqe->timeout_flags); |
3778 | if (flags & ~IORING_TIMEOUT_ABS) | |
5262f567 | 3779 | return -EINVAL; |
bdf20073 | 3780 | |
26a61679 JA |
3781 | req->timeout.count = READ_ONCE(sqe->off); |
3782 | ||
3529d8c2 | 3783 | if (!req->io && io_alloc_async_ctx(req)) |
26a61679 JA |
3784 | return -ENOMEM; |
3785 | ||
3786 | data = &req->io->timeout; | |
ad8a48ac | 3787 | data->req = req; |
ad8a48ac JA |
3788 | req->flags |= REQ_F_TIMEOUT; |
3789 | ||
3790 | if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr))) | |
5262f567 JA |
3791 | return -EFAULT; |
3792 | ||
11365043 | 3793 | if (flags & IORING_TIMEOUT_ABS) |
ad8a48ac | 3794 | data->mode = HRTIMER_MODE_ABS; |
11365043 | 3795 | else |
ad8a48ac | 3796 | data->mode = HRTIMER_MODE_REL; |
11365043 | 3797 | |
ad8a48ac JA |
3798 | hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode); |
3799 | return 0; | |
3800 | } | |
3801 | ||
fc4df999 | 3802 | static int io_timeout(struct io_kiocb *req) |
ad8a48ac JA |
3803 | { |
3804 | unsigned count; | |
3805 | struct io_ring_ctx *ctx = req->ctx; | |
3806 | struct io_timeout_data *data; | |
3807 | struct list_head *entry; | |
3808 | unsigned span = 0; | |
ad8a48ac | 3809 | |
2d28390a | 3810 | data = &req->io->timeout; |
93bd25bb | 3811 | |
5262f567 JA |
3812 | /* |
3813 | * sqe->off holds how many events that need to occur for this | |
93bd25bb JA |
3814 | * timeout event to be satisfied. If it isn't set, then this is |
3815 | * a pure timeout request, sequence isn't used. | |
5262f567 | 3816 | */ |
26a61679 | 3817 | count = req->timeout.count; |
93bd25bb JA |
3818 | if (!count) { |
3819 | req->flags |= REQ_F_TIMEOUT_NOSEQ; | |
3820 | spin_lock_irq(&ctx->completion_lock); | |
3821 | entry = ctx->timeout_list.prev; | |
3822 | goto add; | |
3823 | } | |
5262f567 JA |
3824 | |
3825 | req->sequence = ctx->cached_sq_head + count - 1; | |
2d28390a | 3826 | data->seq_offset = count; |
5262f567 JA |
3827 | |
3828 | /* | |
3829 | * Insertion sort, ensuring the first entry in the list is always | |
3830 | * the one we need first. | |
3831 | */ | |
5262f567 JA |
3832 | spin_lock_irq(&ctx->completion_lock); |
3833 | list_for_each_prev(entry, &ctx->timeout_list) { | |
3834 | struct io_kiocb *nxt = list_entry(entry, struct io_kiocb, list); | |
5da0fb1a | 3835 | unsigned nxt_sq_head; |
3836 | long long tmp, tmp_nxt; | |
2d28390a | 3837 | u32 nxt_offset = nxt->io->timeout.seq_offset; |
5262f567 | 3838 | |
93bd25bb JA |
3839 | if (nxt->flags & REQ_F_TIMEOUT_NOSEQ) |
3840 | continue; | |
3841 | ||
5da0fb1a | 3842 | /* |
3843 | * Since cached_sq_head + count - 1 can overflow, use type long | |
3844 | * long to store it. | |
3845 | */ | |
3846 | tmp = (long long)ctx->cached_sq_head + count - 1; | |
cc42e0ac PB |
3847 | nxt_sq_head = nxt->sequence - nxt_offset + 1; |
3848 | tmp_nxt = (long long)nxt_sq_head + nxt_offset - 1; | |
5da0fb1a | 3849 | |
3850 | /* | |
3851 | * cached_sq_head may overflow, and it will never overflow twice | |
3852 | * once there is some timeout req still be valid. | |
3853 | */ | |
3854 | if (ctx->cached_sq_head < nxt_sq_head) | |
8b07a65a | 3855 | tmp += UINT_MAX; |
5da0fb1a | 3856 | |
a1f58ba4 | 3857 | if (tmp > tmp_nxt) |
5262f567 | 3858 | break; |
a1f58ba4 | 3859 | |
3860 | /* | |
3861 | * Sequence of reqs after the insert one and itself should | |
3862 | * be adjusted because each timeout req consumes a slot. | |
3863 | */ | |
3864 | span++; | |
3865 | nxt->sequence++; | |
5262f567 | 3866 | } |
a1f58ba4 | 3867 | req->sequence -= span; |
93bd25bb | 3868 | add: |
5262f567 | 3869 | list_add(&req->list, entry); |
ad8a48ac JA |
3870 | data->timer.function = io_timeout_fn; |
3871 | hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode); | |
5262f567 | 3872 | spin_unlock_irq(&ctx->completion_lock); |
5262f567 JA |
3873 | return 0; |
3874 | } | |
5262f567 | 3875 | |
62755e35 JA |
3876 | static bool io_cancel_cb(struct io_wq_work *work, void *data) |
3877 | { | |
3878 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); | |
3879 | ||
3880 | return req->user_data == (unsigned long) data; | |
3881 | } | |
3882 | ||
e977d6d3 | 3883 | static int io_async_cancel_one(struct io_ring_ctx *ctx, void *sqe_addr) |
62755e35 | 3884 | { |
62755e35 | 3885 | enum io_wq_cancel cancel_ret; |
62755e35 JA |
3886 | int ret = 0; |
3887 | ||
62755e35 JA |
3888 | cancel_ret = io_wq_cancel_cb(ctx->io_wq, io_cancel_cb, sqe_addr); |
3889 | switch (cancel_ret) { | |
3890 | case IO_WQ_CANCEL_OK: | |
3891 | ret = 0; | |
3892 | break; | |
3893 | case IO_WQ_CANCEL_RUNNING: | |
3894 | ret = -EALREADY; | |
3895 | break; | |
3896 | case IO_WQ_CANCEL_NOTFOUND: | |
3897 | ret = -ENOENT; | |
3898 | break; | |
3899 | } | |
3900 | ||
e977d6d3 JA |
3901 | return ret; |
3902 | } | |
3903 | ||
47f46768 JA |
3904 | static void io_async_find_and_cancel(struct io_ring_ctx *ctx, |
3905 | struct io_kiocb *req, __u64 sqe_addr, | |
b0dd8a41 | 3906 | struct io_kiocb **nxt, int success_ret) |
47f46768 JA |
3907 | { |
3908 | unsigned long flags; | |
3909 | int ret; | |
3910 | ||
3911 | ret = io_async_cancel_one(ctx, (void *) (unsigned long) sqe_addr); | |
3912 | if (ret != -ENOENT) { | |
3913 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
3914 | goto done; | |
3915 | } | |
3916 | ||
3917 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
3918 | ret = io_timeout_cancel(ctx, sqe_addr); | |
3919 | if (ret != -ENOENT) | |
3920 | goto done; | |
3921 | ret = io_poll_cancel(ctx, sqe_addr); | |
3922 | done: | |
b0dd8a41 JA |
3923 | if (!ret) |
3924 | ret = success_ret; | |
47f46768 JA |
3925 | io_cqring_fill_event(req, ret); |
3926 | io_commit_cqring(ctx); | |
3927 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
3928 | io_cqring_ev_posted(ctx); | |
3929 | ||
4e88d6e7 JA |
3930 | if (ret < 0) |
3931 | req_set_fail_links(req); | |
47f46768 JA |
3932 | io_put_req_find_next(req, nxt); |
3933 | } | |
3934 | ||
3529d8c2 JA |
3935 | static int io_async_cancel_prep(struct io_kiocb *req, |
3936 | const struct io_uring_sqe *sqe) | |
e977d6d3 | 3937 | { |
fbf23849 | 3938 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) |
e977d6d3 JA |
3939 | return -EINVAL; |
3940 | if (sqe->flags || sqe->ioprio || sqe->off || sqe->len || | |
3941 | sqe->cancel_flags) | |
3942 | return -EINVAL; | |
3943 | ||
fbf23849 JA |
3944 | req->cancel.addr = READ_ONCE(sqe->addr); |
3945 | return 0; | |
3946 | } | |
3947 | ||
3948 | static int io_async_cancel(struct io_kiocb *req, struct io_kiocb **nxt) | |
3949 | { | |
3950 | struct io_ring_ctx *ctx = req->ctx; | |
fbf23849 JA |
3951 | |
3952 | io_async_find_and_cancel(ctx, req, req->cancel.addr, nxt, 0); | |
5262f567 JA |
3953 | return 0; |
3954 | } | |
3955 | ||
05f3fb3c JA |
3956 | static int io_files_update_prep(struct io_kiocb *req, |
3957 | const struct io_uring_sqe *sqe) | |
3958 | { | |
3959 | if (sqe->flags || sqe->ioprio || sqe->rw_flags) | |
3960 | return -EINVAL; | |
3961 | ||
3962 | req->files_update.offset = READ_ONCE(sqe->off); | |
3963 | req->files_update.nr_args = READ_ONCE(sqe->len); | |
3964 | if (!req->files_update.nr_args) | |
3965 | return -EINVAL; | |
3966 | req->files_update.arg = READ_ONCE(sqe->addr); | |
3967 | return 0; | |
3968 | } | |
3969 | ||
3970 | static int io_files_update(struct io_kiocb *req, bool force_nonblock) | |
3971 | { | |
3972 | struct io_ring_ctx *ctx = req->ctx; | |
3973 | struct io_uring_files_update up; | |
3974 | int ret; | |
3975 | ||
3976 | if (force_nonblock) { | |
3977 | req->work.flags |= IO_WQ_WORK_NEEDS_FILES; | |
3978 | return -EAGAIN; | |
3979 | } | |
3980 | ||
3981 | up.offset = req->files_update.offset; | |
3982 | up.fds = req->files_update.arg; | |
3983 | ||
3984 | mutex_lock(&ctx->uring_lock); | |
3985 | ret = __io_sqe_files_update(ctx, &up, req->files_update.nr_args); | |
3986 | mutex_unlock(&ctx->uring_lock); | |
3987 | ||
3988 | if (ret < 0) | |
3989 | req_set_fail_links(req); | |
3990 | io_cqring_add_event(req, ret); | |
3991 | io_put_req(req); | |
3992 | return 0; | |
3993 | } | |
3994 | ||
3529d8c2 JA |
3995 | static int io_req_defer_prep(struct io_kiocb *req, |
3996 | const struct io_uring_sqe *sqe) | |
f67676d1 | 3997 | { |
e781573e | 3998 | ssize_t ret = 0; |
f67676d1 | 3999 | |
d625c6ee | 4000 | switch (req->opcode) { |
e781573e JA |
4001 | case IORING_OP_NOP: |
4002 | break; | |
f67676d1 JA |
4003 | case IORING_OP_READV: |
4004 | case IORING_OP_READ_FIXED: | |
3a6820f2 | 4005 | case IORING_OP_READ: |
3529d8c2 | 4006 | ret = io_read_prep(req, sqe, true); |
f67676d1 JA |
4007 | break; |
4008 | case IORING_OP_WRITEV: | |
4009 | case IORING_OP_WRITE_FIXED: | |
3a6820f2 | 4010 | case IORING_OP_WRITE: |
3529d8c2 | 4011 | ret = io_write_prep(req, sqe, true); |
f67676d1 | 4012 | break; |
0969e783 | 4013 | case IORING_OP_POLL_ADD: |
3529d8c2 | 4014 | ret = io_poll_add_prep(req, sqe); |
0969e783 JA |
4015 | break; |
4016 | case IORING_OP_POLL_REMOVE: | |
3529d8c2 | 4017 | ret = io_poll_remove_prep(req, sqe); |
0969e783 | 4018 | break; |
8ed8d3c3 | 4019 | case IORING_OP_FSYNC: |
3529d8c2 | 4020 | ret = io_prep_fsync(req, sqe); |
8ed8d3c3 JA |
4021 | break; |
4022 | case IORING_OP_SYNC_FILE_RANGE: | |
3529d8c2 | 4023 | ret = io_prep_sfr(req, sqe); |
8ed8d3c3 | 4024 | break; |
03b1230c | 4025 | case IORING_OP_SENDMSG: |
fddaface | 4026 | case IORING_OP_SEND: |
3529d8c2 | 4027 | ret = io_sendmsg_prep(req, sqe); |
03b1230c JA |
4028 | break; |
4029 | case IORING_OP_RECVMSG: | |
fddaface | 4030 | case IORING_OP_RECV: |
3529d8c2 | 4031 | ret = io_recvmsg_prep(req, sqe); |
03b1230c | 4032 | break; |
f499a021 | 4033 | case IORING_OP_CONNECT: |
3529d8c2 | 4034 | ret = io_connect_prep(req, sqe); |
f499a021 | 4035 | break; |
2d28390a | 4036 | case IORING_OP_TIMEOUT: |
3529d8c2 | 4037 | ret = io_timeout_prep(req, sqe, false); |
b7bb4f7d | 4038 | break; |
b29472ee | 4039 | case IORING_OP_TIMEOUT_REMOVE: |
3529d8c2 | 4040 | ret = io_timeout_remove_prep(req, sqe); |
b29472ee | 4041 | break; |
fbf23849 | 4042 | case IORING_OP_ASYNC_CANCEL: |
3529d8c2 | 4043 | ret = io_async_cancel_prep(req, sqe); |
fbf23849 | 4044 | break; |
2d28390a | 4045 | case IORING_OP_LINK_TIMEOUT: |
3529d8c2 | 4046 | ret = io_timeout_prep(req, sqe, true); |
b7bb4f7d | 4047 | break; |
8ed8d3c3 | 4048 | case IORING_OP_ACCEPT: |
3529d8c2 | 4049 | ret = io_accept_prep(req, sqe); |
8ed8d3c3 | 4050 | break; |
d63d1b5e JA |
4051 | case IORING_OP_FALLOCATE: |
4052 | ret = io_fallocate_prep(req, sqe); | |
4053 | break; | |
15b71abe JA |
4054 | case IORING_OP_OPENAT: |
4055 | ret = io_openat_prep(req, sqe); | |
4056 | break; | |
b5dba59e JA |
4057 | case IORING_OP_CLOSE: |
4058 | ret = io_close_prep(req, sqe); | |
4059 | break; | |
05f3fb3c JA |
4060 | case IORING_OP_FILES_UPDATE: |
4061 | ret = io_files_update_prep(req, sqe); | |
4062 | break; | |
eddc7ef5 JA |
4063 | case IORING_OP_STATX: |
4064 | ret = io_statx_prep(req, sqe); | |
4065 | break; | |
4840e418 JA |
4066 | case IORING_OP_FADVISE: |
4067 | ret = io_fadvise_prep(req, sqe); | |
4068 | break; | |
c1ca757b JA |
4069 | case IORING_OP_MADVISE: |
4070 | ret = io_madvise_prep(req, sqe); | |
4071 | break; | |
cebdb986 JA |
4072 | case IORING_OP_OPENAT2: |
4073 | ret = io_openat2_prep(req, sqe); | |
4074 | break; | |
f67676d1 | 4075 | default: |
e781573e JA |
4076 | printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n", |
4077 | req->opcode); | |
4078 | ret = -EINVAL; | |
b7bb4f7d | 4079 | break; |
f67676d1 JA |
4080 | } |
4081 | ||
b7bb4f7d | 4082 | return ret; |
f67676d1 JA |
4083 | } |
4084 | ||
3529d8c2 | 4085 | static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
de0617e4 | 4086 | { |
a197f664 | 4087 | struct io_ring_ctx *ctx = req->ctx; |
f67676d1 | 4088 | int ret; |
de0617e4 | 4089 | |
9d858b21 BL |
4090 | /* Still need defer if there is pending req in defer list. */ |
4091 | if (!req_need_defer(req) && list_empty(&ctx->defer_list)) | |
de0617e4 JA |
4092 | return 0; |
4093 | ||
3529d8c2 | 4094 | if (!req->io && io_alloc_async_ctx(req)) |
de0617e4 JA |
4095 | return -EAGAIN; |
4096 | ||
3529d8c2 | 4097 | ret = io_req_defer_prep(req, sqe); |
b7bb4f7d | 4098 | if (ret < 0) |
2d28390a | 4099 | return ret; |
2d28390a | 4100 | |
de0617e4 | 4101 | spin_lock_irq(&ctx->completion_lock); |
9d858b21 | 4102 | if (!req_need_defer(req) && list_empty(&ctx->defer_list)) { |
de0617e4 | 4103 | spin_unlock_irq(&ctx->completion_lock); |
de0617e4 JA |
4104 | return 0; |
4105 | } | |
4106 | ||
915967f6 | 4107 | trace_io_uring_defer(ctx, req, req->user_data); |
de0617e4 JA |
4108 | list_add_tail(&req->list, &ctx->defer_list); |
4109 | spin_unlock_irq(&ctx->completion_lock); | |
4110 | return -EIOCBQUEUED; | |
4111 | } | |
4112 | ||
3529d8c2 JA |
4113 | static int io_issue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
4114 | struct io_kiocb **nxt, bool force_nonblock) | |
2b188cc1 | 4115 | { |
a197f664 | 4116 | struct io_ring_ctx *ctx = req->ctx; |
d625c6ee | 4117 | int ret; |
2b188cc1 | 4118 | |
d625c6ee | 4119 | switch (req->opcode) { |
2b188cc1 | 4120 | case IORING_OP_NOP: |
78e19bbe | 4121 | ret = io_nop(req); |
2b188cc1 JA |
4122 | break; |
4123 | case IORING_OP_READV: | |
edafccee | 4124 | case IORING_OP_READ_FIXED: |
3a6820f2 | 4125 | case IORING_OP_READ: |
3529d8c2 JA |
4126 | if (sqe) { |
4127 | ret = io_read_prep(req, sqe, force_nonblock); | |
4128 | if (ret < 0) | |
4129 | break; | |
4130 | } | |
267bc904 | 4131 | ret = io_read(req, nxt, force_nonblock); |
edafccee | 4132 | break; |
3529d8c2 | 4133 | case IORING_OP_WRITEV: |
edafccee | 4134 | case IORING_OP_WRITE_FIXED: |
3a6820f2 | 4135 | case IORING_OP_WRITE: |
3529d8c2 JA |
4136 | if (sqe) { |
4137 | ret = io_write_prep(req, sqe, force_nonblock); | |
4138 | if (ret < 0) | |
4139 | break; | |
4140 | } | |
267bc904 | 4141 | ret = io_write(req, nxt, force_nonblock); |
2b188cc1 | 4142 | break; |
c992fe29 | 4143 | case IORING_OP_FSYNC: |
3529d8c2 JA |
4144 | if (sqe) { |
4145 | ret = io_prep_fsync(req, sqe); | |
4146 | if (ret < 0) | |
4147 | break; | |
4148 | } | |
fc4df999 | 4149 | ret = io_fsync(req, nxt, force_nonblock); |
c992fe29 | 4150 | break; |
221c5eb2 | 4151 | case IORING_OP_POLL_ADD: |
3529d8c2 JA |
4152 | if (sqe) { |
4153 | ret = io_poll_add_prep(req, sqe); | |
4154 | if (ret) | |
4155 | break; | |
4156 | } | |
fc4df999 | 4157 | ret = io_poll_add(req, nxt); |
221c5eb2 JA |
4158 | break; |
4159 | case IORING_OP_POLL_REMOVE: | |
3529d8c2 JA |
4160 | if (sqe) { |
4161 | ret = io_poll_remove_prep(req, sqe); | |
4162 | if (ret < 0) | |
4163 | break; | |
4164 | } | |
fc4df999 | 4165 | ret = io_poll_remove(req); |
221c5eb2 | 4166 | break; |
5d17b4a4 | 4167 | case IORING_OP_SYNC_FILE_RANGE: |
3529d8c2 JA |
4168 | if (sqe) { |
4169 | ret = io_prep_sfr(req, sqe); | |
4170 | if (ret < 0) | |
4171 | break; | |
4172 | } | |
fc4df999 | 4173 | ret = io_sync_file_range(req, nxt, force_nonblock); |
5d17b4a4 | 4174 | break; |
0fa03c62 | 4175 | case IORING_OP_SENDMSG: |
fddaface | 4176 | case IORING_OP_SEND: |
3529d8c2 JA |
4177 | if (sqe) { |
4178 | ret = io_sendmsg_prep(req, sqe); | |
4179 | if (ret < 0) | |
4180 | break; | |
4181 | } | |
fddaface JA |
4182 | if (req->opcode == IORING_OP_SENDMSG) |
4183 | ret = io_sendmsg(req, nxt, force_nonblock); | |
4184 | else | |
4185 | ret = io_send(req, nxt, force_nonblock); | |
0fa03c62 | 4186 | break; |
aa1fa28f | 4187 | case IORING_OP_RECVMSG: |
fddaface | 4188 | case IORING_OP_RECV: |
3529d8c2 JA |
4189 | if (sqe) { |
4190 | ret = io_recvmsg_prep(req, sqe); | |
4191 | if (ret) | |
4192 | break; | |
4193 | } | |
fddaface JA |
4194 | if (req->opcode == IORING_OP_RECVMSG) |
4195 | ret = io_recvmsg(req, nxt, force_nonblock); | |
4196 | else | |
4197 | ret = io_recv(req, nxt, force_nonblock); | |
aa1fa28f | 4198 | break; |
5262f567 | 4199 | case IORING_OP_TIMEOUT: |
3529d8c2 JA |
4200 | if (sqe) { |
4201 | ret = io_timeout_prep(req, sqe, false); | |
4202 | if (ret) | |
4203 | break; | |
4204 | } | |
fc4df999 | 4205 | ret = io_timeout(req); |
5262f567 | 4206 | break; |
11365043 | 4207 | case IORING_OP_TIMEOUT_REMOVE: |
3529d8c2 JA |
4208 | if (sqe) { |
4209 | ret = io_timeout_remove_prep(req, sqe); | |
4210 | if (ret) | |
4211 | break; | |
4212 | } | |
fc4df999 | 4213 | ret = io_timeout_remove(req); |
11365043 | 4214 | break; |
17f2fe35 | 4215 | case IORING_OP_ACCEPT: |
3529d8c2 JA |
4216 | if (sqe) { |
4217 | ret = io_accept_prep(req, sqe); | |
4218 | if (ret) | |
4219 | break; | |
4220 | } | |
fc4df999 | 4221 | ret = io_accept(req, nxt, force_nonblock); |
17f2fe35 | 4222 | break; |
f8e85cf2 | 4223 | case IORING_OP_CONNECT: |
3529d8c2 JA |
4224 | if (sqe) { |
4225 | ret = io_connect_prep(req, sqe); | |
4226 | if (ret) | |
4227 | break; | |
4228 | } | |
fc4df999 | 4229 | ret = io_connect(req, nxt, force_nonblock); |
f8e85cf2 | 4230 | break; |
62755e35 | 4231 | case IORING_OP_ASYNC_CANCEL: |
3529d8c2 JA |
4232 | if (sqe) { |
4233 | ret = io_async_cancel_prep(req, sqe); | |
4234 | if (ret) | |
4235 | break; | |
4236 | } | |
fc4df999 | 4237 | ret = io_async_cancel(req, nxt); |
62755e35 | 4238 | break; |
d63d1b5e JA |
4239 | case IORING_OP_FALLOCATE: |
4240 | if (sqe) { | |
4241 | ret = io_fallocate_prep(req, sqe); | |
4242 | if (ret) | |
4243 | break; | |
4244 | } | |
4245 | ret = io_fallocate(req, nxt, force_nonblock); | |
4246 | break; | |
15b71abe JA |
4247 | case IORING_OP_OPENAT: |
4248 | if (sqe) { | |
4249 | ret = io_openat_prep(req, sqe); | |
4250 | if (ret) | |
4251 | break; | |
4252 | } | |
4253 | ret = io_openat(req, nxt, force_nonblock); | |
4254 | break; | |
b5dba59e JA |
4255 | case IORING_OP_CLOSE: |
4256 | if (sqe) { | |
4257 | ret = io_close_prep(req, sqe); | |
4258 | if (ret) | |
4259 | break; | |
4260 | } | |
4261 | ret = io_close(req, nxt, force_nonblock); | |
4262 | break; | |
05f3fb3c JA |
4263 | case IORING_OP_FILES_UPDATE: |
4264 | if (sqe) { | |
4265 | ret = io_files_update_prep(req, sqe); | |
4266 | if (ret) | |
4267 | break; | |
4268 | } | |
4269 | ret = io_files_update(req, force_nonblock); | |
4270 | break; | |
eddc7ef5 JA |
4271 | case IORING_OP_STATX: |
4272 | if (sqe) { | |
4273 | ret = io_statx_prep(req, sqe); | |
4274 | if (ret) | |
4275 | break; | |
4276 | } | |
4277 | ret = io_statx(req, nxt, force_nonblock); | |
4278 | break; | |
4840e418 JA |
4279 | case IORING_OP_FADVISE: |
4280 | if (sqe) { | |
4281 | ret = io_fadvise_prep(req, sqe); | |
4282 | if (ret) | |
4283 | break; | |
4284 | } | |
4285 | ret = io_fadvise(req, nxt, force_nonblock); | |
4286 | break; | |
c1ca757b JA |
4287 | case IORING_OP_MADVISE: |
4288 | if (sqe) { | |
4289 | ret = io_madvise_prep(req, sqe); | |
4290 | if (ret) | |
4291 | break; | |
4292 | } | |
4293 | ret = io_madvise(req, nxt, force_nonblock); | |
4294 | break; | |
cebdb986 JA |
4295 | case IORING_OP_OPENAT2: |
4296 | if (sqe) { | |
4297 | ret = io_openat2_prep(req, sqe); | |
4298 | if (ret) | |
4299 | break; | |
4300 | } | |
4301 | ret = io_openat2(req, nxt, force_nonblock); | |
4302 | break; | |
2b188cc1 JA |
4303 | default: |
4304 | ret = -EINVAL; | |
4305 | break; | |
4306 | } | |
4307 | ||
def596e9 JA |
4308 | if (ret) |
4309 | return ret; | |
4310 | ||
4311 | if (ctx->flags & IORING_SETUP_IOPOLL) { | |
11ba820b JA |
4312 | const bool in_async = io_wq_current_is_worker(); |
4313 | ||
9e645e11 | 4314 | if (req->result == -EAGAIN) |
def596e9 JA |
4315 | return -EAGAIN; |
4316 | ||
11ba820b JA |
4317 | /* workqueue context doesn't hold uring_lock, grab it now */ |
4318 | if (in_async) | |
4319 | mutex_lock(&ctx->uring_lock); | |
4320 | ||
def596e9 | 4321 | io_iopoll_req_issued(req); |
11ba820b JA |
4322 | |
4323 | if (in_async) | |
4324 | mutex_unlock(&ctx->uring_lock); | |
def596e9 JA |
4325 | } |
4326 | ||
4327 | return 0; | |
2b188cc1 JA |
4328 | } |
4329 | ||
561fb04a | 4330 | static void io_wq_submit_work(struct io_wq_work **workptr) |
2b188cc1 | 4331 | { |
561fb04a | 4332 | struct io_wq_work *work = *workptr; |
2b188cc1 | 4333 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); |
561fb04a JA |
4334 | struct io_kiocb *nxt = NULL; |
4335 | int ret = 0; | |
2b188cc1 | 4336 | |
0c9d5ccd JA |
4337 | /* if NO_CANCEL is set, we must still run the work */ |
4338 | if ((work->flags & (IO_WQ_WORK_CANCEL|IO_WQ_WORK_NO_CANCEL)) == | |
4339 | IO_WQ_WORK_CANCEL) { | |
561fb04a | 4340 | ret = -ECANCELED; |
0c9d5ccd | 4341 | } |
31b51510 | 4342 | |
561fb04a | 4343 | if (!ret) { |
cf6fd4bd PB |
4344 | req->has_user = (work->flags & IO_WQ_WORK_HAS_MM) != 0; |
4345 | req->in_async = true; | |
561fb04a | 4346 | do { |
3529d8c2 | 4347 | ret = io_issue_sqe(req, NULL, &nxt, false); |
561fb04a JA |
4348 | /* |
4349 | * We can get EAGAIN for polled IO even though we're | |
4350 | * forcing a sync submission from here, since we can't | |
4351 | * wait for request slots on the block side. | |
4352 | */ | |
4353 | if (ret != -EAGAIN) | |
4354 | break; | |
4355 | cond_resched(); | |
4356 | } while (1); | |
4357 | } | |
31b51510 | 4358 | |
561fb04a | 4359 | /* drop submission reference */ |
ec9c02ad | 4360 | io_put_req(req); |
817869d2 | 4361 | |
561fb04a | 4362 | if (ret) { |
4e88d6e7 | 4363 | req_set_fail_links(req); |
78e19bbe | 4364 | io_cqring_add_event(req, ret); |
817869d2 | 4365 | io_put_req(req); |
edafccee | 4366 | } |
2b188cc1 | 4367 | |
561fb04a | 4368 | /* if a dependent link is ready, pass it back */ |
78912934 JA |
4369 | if (!ret && nxt) |
4370 | io_wq_assign_next(workptr, nxt); | |
2b188cc1 JA |
4371 | } |
4372 | ||
15b71abe | 4373 | static int io_req_needs_file(struct io_kiocb *req, int fd) |
09bb8394 | 4374 | { |
d3656344 | 4375 | if (!io_op_defs[req->opcode].needs_file) |
9e3aa61a | 4376 | return 0; |
d3656344 JA |
4377 | if (fd == -1 && io_op_defs[req->opcode].fd_non_neg) |
4378 | return 0; | |
4379 | return 1; | |
09bb8394 JA |
4380 | } |
4381 | ||
65e19f54 JA |
4382 | static inline struct file *io_file_from_index(struct io_ring_ctx *ctx, |
4383 | int index) | |
4384 | { | |
4385 | struct fixed_file_table *table; | |
4386 | ||
05f3fb3c JA |
4387 | table = &ctx->file_data->table[index >> IORING_FILE_TABLE_SHIFT]; |
4388 | return table->files[index & IORING_FILE_TABLE_MASK];; | |
65e19f54 JA |
4389 | } |
4390 | ||
3529d8c2 JA |
4391 | static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req, |
4392 | const struct io_uring_sqe *sqe) | |
09bb8394 | 4393 | { |
a197f664 | 4394 | struct io_ring_ctx *ctx = req->ctx; |
09bb8394 | 4395 | unsigned flags; |
d3656344 | 4396 | int fd; |
09bb8394 | 4397 | |
3529d8c2 JA |
4398 | flags = READ_ONCE(sqe->flags); |
4399 | fd = READ_ONCE(sqe->fd); | |
09bb8394 | 4400 | |
d3656344 JA |
4401 | if (!io_req_needs_file(req, fd)) |
4402 | return 0; | |
09bb8394 JA |
4403 | |
4404 | if (flags & IOSQE_FIXED_FILE) { | |
05f3fb3c | 4405 | if (unlikely(!ctx->file_data || |
09bb8394 JA |
4406 | (unsigned) fd >= ctx->nr_user_files)) |
4407 | return -EBADF; | |
b7620121 | 4408 | fd = array_index_nospec(fd, ctx->nr_user_files); |
65e19f54 JA |
4409 | req->file = io_file_from_index(ctx, fd); |
4410 | if (!req->file) | |
08a45173 | 4411 | return -EBADF; |
09bb8394 | 4412 | req->flags |= REQ_F_FIXED_FILE; |
05f3fb3c | 4413 | percpu_ref_get(&ctx->file_data->refs); |
09bb8394 | 4414 | } else { |
cf6fd4bd | 4415 | if (req->needs_fixed_file) |
09bb8394 | 4416 | return -EBADF; |
c826bd7a | 4417 | trace_io_uring_file_get(ctx, fd); |
09bb8394 JA |
4418 | req->file = io_file_get(state, fd); |
4419 | if (unlikely(!req->file)) | |
4420 | return -EBADF; | |
4421 | } | |
4422 | ||
4423 | return 0; | |
4424 | } | |
4425 | ||
a197f664 | 4426 | static int io_grab_files(struct io_kiocb *req) |
fcb323cc JA |
4427 | { |
4428 | int ret = -EBADF; | |
a197f664 | 4429 | struct io_ring_ctx *ctx = req->ctx; |
fcb323cc | 4430 | |
b14cca0c | 4431 | if (!ctx->ring_file) |
b5dba59e JA |
4432 | return -EBADF; |
4433 | ||
fcb323cc JA |
4434 | rcu_read_lock(); |
4435 | spin_lock_irq(&ctx->inflight_lock); | |
4436 | /* | |
4437 | * We use the f_ops->flush() handler to ensure that we can flush | |
4438 | * out work accessing these files if the fd is closed. Check if | |
4439 | * the fd has changed since we started down this path, and disallow | |
4440 | * this operation if it has. | |
4441 | */ | |
b14cca0c | 4442 | if (fcheck(ctx->ring_fd) == ctx->ring_file) { |
fcb323cc JA |
4443 | list_add(&req->inflight_entry, &ctx->inflight_list); |
4444 | req->flags |= REQ_F_INFLIGHT; | |
4445 | req->work.files = current->files; | |
4446 | ret = 0; | |
4447 | } | |
4448 | spin_unlock_irq(&ctx->inflight_lock); | |
4449 | rcu_read_unlock(); | |
4450 | ||
4451 | return ret; | |
4452 | } | |
4453 | ||
2665abfd | 4454 | static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer) |
2b188cc1 | 4455 | { |
ad8a48ac JA |
4456 | struct io_timeout_data *data = container_of(timer, |
4457 | struct io_timeout_data, timer); | |
4458 | struct io_kiocb *req = data->req; | |
2665abfd JA |
4459 | struct io_ring_ctx *ctx = req->ctx; |
4460 | struct io_kiocb *prev = NULL; | |
4461 | unsigned long flags; | |
2665abfd JA |
4462 | |
4463 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
4464 | ||
4465 | /* | |
4466 | * We don't expect the list to be empty, that will only happen if we | |
4467 | * race with the completion of the linked work. | |
4468 | */ | |
4493233e PB |
4469 | if (!list_empty(&req->link_list)) { |
4470 | prev = list_entry(req->link_list.prev, struct io_kiocb, | |
4471 | link_list); | |
5d960724 | 4472 | if (refcount_inc_not_zero(&prev->refs)) { |
4493233e | 4473 | list_del_init(&req->link_list); |
5d960724 JA |
4474 | prev->flags &= ~REQ_F_LINK_TIMEOUT; |
4475 | } else | |
76a46e06 | 4476 | prev = NULL; |
2665abfd JA |
4477 | } |
4478 | ||
4479 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
4480 | ||
4481 | if (prev) { | |
4e88d6e7 | 4482 | req_set_fail_links(prev); |
b0dd8a41 JA |
4483 | io_async_find_and_cancel(ctx, req, prev->user_data, NULL, |
4484 | -ETIME); | |
76a46e06 | 4485 | io_put_req(prev); |
47f46768 JA |
4486 | } else { |
4487 | io_cqring_add_event(req, -ETIME); | |
4488 | io_put_req(req); | |
2665abfd | 4489 | } |
2665abfd JA |
4490 | return HRTIMER_NORESTART; |
4491 | } | |
4492 | ||
ad8a48ac | 4493 | static void io_queue_linked_timeout(struct io_kiocb *req) |
2665abfd | 4494 | { |
76a46e06 | 4495 | struct io_ring_ctx *ctx = req->ctx; |
2665abfd | 4496 | |
76a46e06 JA |
4497 | /* |
4498 | * If the list is now empty, then our linked request finished before | |
4499 | * we got a chance to setup the timer | |
4500 | */ | |
4501 | spin_lock_irq(&ctx->completion_lock); | |
4493233e | 4502 | if (!list_empty(&req->link_list)) { |
2d28390a | 4503 | struct io_timeout_data *data = &req->io->timeout; |
94ae5e77 | 4504 | |
ad8a48ac JA |
4505 | data->timer.function = io_link_timeout_fn; |
4506 | hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), | |
4507 | data->mode); | |
2665abfd | 4508 | } |
76a46e06 | 4509 | spin_unlock_irq(&ctx->completion_lock); |
2665abfd | 4510 | |
2665abfd | 4511 | /* drop submission reference */ |
76a46e06 JA |
4512 | io_put_req(req); |
4513 | } | |
2665abfd | 4514 | |
ad8a48ac | 4515 | static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) |
2665abfd JA |
4516 | { |
4517 | struct io_kiocb *nxt; | |
4518 | ||
4519 | if (!(req->flags & REQ_F_LINK)) | |
4520 | return NULL; | |
4521 | ||
4493233e PB |
4522 | nxt = list_first_entry_or_null(&req->link_list, struct io_kiocb, |
4523 | link_list); | |
d625c6ee | 4524 | if (!nxt || nxt->opcode != IORING_OP_LINK_TIMEOUT) |
76a46e06 | 4525 | return NULL; |
2665abfd | 4526 | |
76a46e06 | 4527 | req->flags |= REQ_F_LINK_TIMEOUT; |
76a46e06 | 4528 | return nxt; |
2665abfd JA |
4529 | } |
4530 | ||
3529d8c2 | 4531 | static void __io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2b188cc1 | 4532 | { |
4a0a7a18 | 4533 | struct io_kiocb *linked_timeout; |
f9bd67f6 | 4534 | struct io_kiocb *nxt = NULL; |
e0c5c576 | 4535 | int ret; |
2b188cc1 | 4536 | |
4a0a7a18 JA |
4537 | again: |
4538 | linked_timeout = io_prep_linked_timeout(req); | |
4539 | ||
3529d8c2 | 4540 | ret = io_issue_sqe(req, sqe, &nxt, true); |
491381ce JA |
4541 | |
4542 | /* | |
4543 | * We async punt it if the file wasn't marked NOWAIT, or if the file | |
4544 | * doesn't support non-blocking read/write attempts | |
4545 | */ | |
4546 | if (ret == -EAGAIN && (!(req->flags & REQ_F_NOWAIT) || | |
4547 | (req->flags & REQ_F_MUST_PUNT))) { | |
bbad27b2 PB |
4548 | if (req->work.flags & IO_WQ_WORK_NEEDS_FILES) { |
4549 | ret = io_grab_files(req); | |
4550 | if (ret) | |
4551 | goto err; | |
2b188cc1 | 4552 | } |
bbad27b2 PB |
4553 | |
4554 | /* | |
4555 | * Queued up for async execution, worker will release | |
4556 | * submit reference when the iocb is actually submitted. | |
4557 | */ | |
4558 | io_queue_async_work(req); | |
4a0a7a18 | 4559 | goto done_req; |
2b188cc1 | 4560 | } |
e65ef56d | 4561 | |
fcb323cc | 4562 | err: |
76a46e06 | 4563 | /* drop submission reference */ |
ec9c02ad | 4564 | io_put_req(req); |
e65ef56d | 4565 | |
f9bd67f6 | 4566 | if (linked_timeout) { |
76a46e06 | 4567 | if (!ret) |
f9bd67f6 | 4568 | io_queue_linked_timeout(linked_timeout); |
76a46e06 | 4569 | else |
f9bd67f6 | 4570 | io_put_req(linked_timeout); |
76a46e06 JA |
4571 | } |
4572 | ||
e65ef56d | 4573 | /* and drop final reference, if we failed */ |
9e645e11 | 4574 | if (ret) { |
78e19bbe | 4575 | io_cqring_add_event(req, ret); |
4e88d6e7 | 4576 | req_set_fail_links(req); |
e65ef56d | 4577 | io_put_req(req); |
9e645e11 | 4578 | } |
4a0a7a18 JA |
4579 | done_req: |
4580 | if (nxt) { | |
4581 | req = nxt; | |
4582 | nxt = NULL; | |
4583 | goto again; | |
4584 | } | |
2b188cc1 JA |
4585 | } |
4586 | ||
3529d8c2 | 4587 | static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
4fe2c963 JL |
4588 | { |
4589 | int ret; | |
4590 | ||
3529d8c2 | 4591 | ret = io_req_defer(req, sqe); |
4fe2c963 JL |
4592 | if (ret) { |
4593 | if (ret != -EIOCBQUEUED) { | |
78e19bbe | 4594 | io_cqring_add_event(req, ret); |
4e88d6e7 | 4595 | req_set_fail_links(req); |
78e19bbe | 4596 | io_double_put_req(req); |
4fe2c963 | 4597 | } |
2550878f | 4598 | } else if (req->flags & REQ_F_FORCE_ASYNC) { |
ce35a47a JA |
4599 | /* |
4600 | * Never try inline submit of IOSQE_ASYNC is set, go straight | |
4601 | * to async execution. | |
4602 | */ | |
4603 | req->work.flags |= IO_WQ_WORK_CONCURRENT; | |
4604 | io_queue_async_work(req); | |
4605 | } else { | |
3529d8c2 | 4606 | __io_queue_sqe(req, sqe); |
ce35a47a | 4607 | } |
4fe2c963 JL |
4608 | } |
4609 | ||
1b4a51b6 | 4610 | static inline void io_queue_link_head(struct io_kiocb *req) |
4fe2c963 | 4611 | { |
94ae5e77 | 4612 | if (unlikely(req->flags & REQ_F_FAIL_LINK)) { |
1b4a51b6 PB |
4613 | io_cqring_add_event(req, -ECANCELED); |
4614 | io_double_put_req(req); | |
4615 | } else | |
3529d8c2 | 4616 | io_queue_sqe(req, NULL); |
4fe2c963 JL |
4617 | } |
4618 | ||
4e88d6e7 | 4619 | #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \ |
ce35a47a | 4620 | IOSQE_IO_HARDLINK | IOSQE_ASYNC) |
9e645e11 | 4621 | |
3529d8c2 JA |
4622 | static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
4623 | struct io_submit_state *state, struct io_kiocb **link) | |
9e645e11 | 4624 | { |
a197f664 | 4625 | struct io_ring_ctx *ctx = req->ctx; |
32fe525b | 4626 | unsigned int sqe_flags; |
9e645e11 JA |
4627 | int ret; |
4628 | ||
32fe525b PB |
4629 | sqe_flags = READ_ONCE(sqe->flags); |
4630 | ||
9e645e11 | 4631 | /* enforce forwards compatibility on users */ |
32fe525b | 4632 | if (unlikely(sqe_flags & ~SQE_VALID_FLAGS)) { |
9e645e11 | 4633 | ret = -EINVAL; |
196be95c | 4634 | goto err_req; |
9e645e11 | 4635 | } |
6b47ee6e PB |
4636 | /* same numerical values with corresponding REQ_F_*, safe to copy */ |
4637 | req->flags |= sqe_flags & (IOSQE_IO_DRAIN|IOSQE_IO_HARDLINK| | |
4638 | IOSQE_ASYNC); | |
9e645e11 | 4639 | |
3529d8c2 | 4640 | ret = io_req_set_file(state, req, sqe); |
9e645e11 JA |
4641 | if (unlikely(ret)) { |
4642 | err_req: | |
78e19bbe JA |
4643 | io_cqring_add_event(req, ret); |
4644 | io_double_put_req(req); | |
2e6e1fde | 4645 | return false; |
9e645e11 JA |
4646 | } |
4647 | ||
9e645e11 JA |
4648 | /* |
4649 | * If we already have a head request, queue this one for async | |
4650 | * submittal once the head completes. If we don't have a head but | |
4651 | * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be | |
4652 | * submitted sync once the chain is complete. If none of those | |
4653 | * conditions are true (normal request), then just queue it. | |
4654 | */ | |
4655 | if (*link) { | |
9d76377f | 4656 | struct io_kiocb *head = *link; |
9e645e11 | 4657 | |
711be031 PB |
4658 | if (sqe_flags & IOSQE_IO_DRAIN) { |
4659 | head->flags |= REQ_F_IO_DRAIN; | |
4660 | ctx->drain_next = 1; | |
4661 | } | |
b7bb4f7d | 4662 | if (io_alloc_async_ctx(req)) { |
9e645e11 JA |
4663 | ret = -EAGAIN; |
4664 | goto err_req; | |
4665 | } | |
4666 | ||
3529d8c2 | 4667 | ret = io_req_defer_prep(req, sqe); |
2d28390a | 4668 | if (ret) { |
4e88d6e7 | 4669 | /* fail even hard links since we don't submit */ |
9d76377f | 4670 | head->flags |= REQ_F_FAIL_LINK; |
f67676d1 | 4671 | goto err_req; |
2d28390a | 4672 | } |
9d76377f PB |
4673 | trace_io_uring_link(ctx, req, head); |
4674 | list_add_tail(&req->link_list, &head->link_list); | |
32fe525b PB |
4675 | |
4676 | /* last request of a link, enqueue the link */ | |
4677 | if (!(sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK))) { | |
4678 | io_queue_link_head(head); | |
4679 | *link = NULL; | |
4680 | } | |
9e645e11 | 4681 | } else { |
711be031 PB |
4682 | if (unlikely(ctx->drain_next)) { |
4683 | req->flags |= REQ_F_IO_DRAIN; | |
4684 | req->ctx->drain_next = 0; | |
4685 | } | |
4686 | if (sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) { | |
4687 | req->flags |= REQ_F_LINK; | |
711be031 PB |
4688 | INIT_LIST_HEAD(&req->link_list); |
4689 | ret = io_req_defer_prep(req, sqe); | |
4690 | if (ret) | |
4691 | req->flags |= REQ_F_FAIL_LINK; | |
4692 | *link = req; | |
4693 | } else { | |
4694 | io_queue_sqe(req, sqe); | |
4695 | } | |
9e645e11 | 4696 | } |
2e6e1fde PB |
4697 | |
4698 | return true; | |
9e645e11 JA |
4699 | } |
4700 | ||
9a56a232 JA |
4701 | /* |
4702 | * Batched submission is done, ensure local IO is flushed out. | |
4703 | */ | |
4704 | static void io_submit_state_end(struct io_submit_state *state) | |
4705 | { | |
4706 | blk_finish_plug(&state->plug); | |
3d6770fb | 4707 | io_file_put(state); |
2579f913 JA |
4708 | if (state->free_reqs) |
4709 | kmem_cache_free_bulk(req_cachep, state->free_reqs, | |
4710 | &state->reqs[state->cur_req]); | |
9a56a232 JA |
4711 | } |
4712 | ||
4713 | /* | |
4714 | * Start submission side cache. | |
4715 | */ | |
4716 | static void io_submit_state_start(struct io_submit_state *state, | |
22efde59 | 4717 | unsigned int max_ios) |
9a56a232 JA |
4718 | { |
4719 | blk_start_plug(&state->plug); | |
2579f913 | 4720 | state->free_reqs = 0; |
9a56a232 JA |
4721 | state->file = NULL; |
4722 | state->ios_left = max_ios; | |
4723 | } | |
4724 | ||
2b188cc1 JA |
4725 | static void io_commit_sqring(struct io_ring_ctx *ctx) |
4726 | { | |
75b28aff | 4727 | struct io_rings *rings = ctx->rings; |
2b188cc1 | 4728 | |
caf582c6 PB |
4729 | /* |
4730 | * Ensure any loads from the SQEs are done at this point, | |
4731 | * since once we write the new head, the application could | |
4732 | * write new data to them. | |
4733 | */ | |
4734 | smp_store_release(&rings->sq.head, ctx->cached_sq_head); | |
2b188cc1 JA |
4735 | } |
4736 | ||
2b188cc1 | 4737 | /* |
3529d8c2 | 4738 | * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory |
2b188cc1 JA |
4739 | * that is mapped by userspace. This means that care needs to be taken to |
4740 | * ensure that reads are stable, as we cannot rely on userspace always | |
4741 | * being a good citizen. If members of the sqe are validated and then later | |
4742 | * used, it's important that those reads are done through READ_ONCE() to | |
4743 | * prevent a re-load down the line. | |
4744 | */ | |
3529d8c2 JA |
4745 | static bool io_get_sqring(struct io_ring_ctx *ctx, struct io_kiocb *req, |
4746 | const struct io_uring_sqe **sqe_ptr) | |
2b188cc1 | 4747 | { |
75b28aff | 4748 | u32 *sq_array = ctx->sq_array; |
2b188cc1 JA |
4749 | unsigned head; |
4750 | ||
4751 | /* | |
4752 | * The cached sq head (or cq tail) serves two purposes: | |
4753 | * | |
4754 | * 1) allows us to batch the cost of updating the user visible | |
4755 | * head updates. | |
4756 | * 2) allows the kernel side to track the head on its own, even | |
4757 | * though the application is the one updating it. | |
4758 | */ | |
ee7d46d9 | 4759 | head = READ_ONCE(sq_array[ctx->cached_sq_head & ctx->sq_mask]); |
9835d6fa | 4760 | if (likely(head < ctx->sq_entries)) { |
cf6fd4bd PB |
4761 | /* |
4762 | * All io need record the previous position, if LINK vs DARIN, | |
4763 | * it can be used to mark the position of the first IO in the | |
4764 | * link list. | |
4765 | */ | |
4766 | req->sequence = ctx->cached_sq_head; | |
3529d8c2 JA |
4767 | *sqe_ptr = &ctx->sq_sqes[head]; |
4768 | req->opcode = READ_ONCE((*sqe_ptr)->opcode); | |
4769 | req->user_data = READ_ONCE((*sqe_ptr)->user_data); | |
2b188cc1 JA |
4770 | ctx->cached_sq_head++; |
4771 | return true; | |
4772 | } | |
4773 | ||
4774 | /* drop invalid entries */ | |
4775 | ctx->cached_sq_head++; | |
498ccd9e | 4776 | ctx->cached_sq_dropped++; |
ee7d46d9 | 4777 | WRITE_ONCE(ctx->rings->sq_dropped, ctx->cached_sq_dropped); |
2b188cc1 JA |
4778 | return false; |
4779 | } | |
4780 | ||
fb5ccc98 | 4781 | static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, |
ae9428ca PB |
4782 | struct file *ring_file, int ring_fd, |
4783 | struct mm_struct **mm, bool async) | |
6c271ce2 JA |
4784 | { |
4785 | struct io_submit_state state, *statep = NULL; | |
9e645e11 | 4786 | struct io_kiocb *link = NULL; |
9e645e11 | 4787 | int i, submitted = 0; |
95a1b3ff | 4788 | bool mm_fault = false; |
6c271ce2 | 4789 | |
c4a2ed72 | 4790 | /* if we have a backlog and couldn't flush it all, return BUSY */ |
ad3eb2c8 JA |
4791 | if (test_bit(0, &ctx->sq_check_overflow)) { |
4792 | if (!list_empty(&ctx->cq_overflow_list) && | |
4793 | !io_cqring_overflow_flush(ctx, false)) | |
4794 | return -EBUSY; | |
4795 | } | |
6c271ce2 | 4796 | |
ee7d46d9 PB |
4797 | /* make sure SQ entry isn't read before tail */ |
4798 | nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx)); | |
9ef4f124 | 4799 | |
2b85edfc PB |
4800 | if (!percpu_ref_tryget_many(&ctx->refs, nr)) |
4801 | return -EAGAIN; | |
4802 | ||
6c271ce2 | 4803 | if (nr > IO_PLUG_THRESHOLD) { |
22efde59 | 4804 | io_submit_state_start(&state, nr); |
6c271ce2 JA |
4805 | statep = &state; |
4806 | } | |
4807 | ||
b14cca0c PB |
4808 | ctx->ring_fd = ring_fd; |
4809 | ctx->ring_file = ring_file; | |
4810 | ||
6c271ce2 | 4811 | for (i = 0; i < nr; i++) { |
3529d8c2 | 4812 | const struct io_uring_sqe *sqe; |
196be95c | 4813 | struct io_kiocb *req; |
fb5ccc98 | 4814 | |
196be95c PB |
4815 | req = io_get_req(ctx, statep); |
4816 | if (unlikely(!req)) { | |
4817 | if (!submitted) | |
4818 | submitted = -EAGAIN; | |
fb5ccc98 | 4819 | break; |
196be95c | 4820 | } |
3529d8c2 | 4821 | if (!io_get_sqring(ctx, req, &sqe)) { |
2b85edfc | 4822 | __io_req_do_free(req); |
196be95c PB |
4823 | break; |
4824 | } | |
fb5ccc98 | 4825 | |
d3656344 JA |
4826 | /* will complete beyond this point, count as submitted */ |
4827 | submitted++; | |
4828 | ||
4829 | if (unlikely(req->opcode >= IORING_OP_LAST)) { | |
4830 | io_cqring_add_event(req, -EINVAL); | |
4831 | io_double_put_req(req); | |
4832 | break; | |
4833 | } | |
4834 | ||
4835 | if (io_op_defs[req->opcode].needs_mm && !*mm) { | |
95a1b3ff PB |
4836 | mm_fault = mm_fault || !mmget_not_zero(ctx->sqo_mm); |
4837 | if (!mm_fault) { | |
4838 | use_mm(ctx->sqo_mm); | |
4839 | *mm = ctx->sqo_mm; | |
4840 | } | |
9e645e11 | 4841 | } |
9e645e11 | 4842 | |
cf6fd4bd PB |
4843 | req->has_user = *mm != NULL; |
4844 | req->in_async = async; | |
4845 | req->needs_fixed_file = async; | |
354420f7 JA |
4846 | trace_io_uring_submit_sqe(ctx, req->opcode, req->user_data, |
4847 | true, async); | |
3529d8c2 | 4848 | if (!io_submit_sqe(req, sqe, statep, &link)) |
2e6e1fde | 4849 | break; |
6c271ce2 JA |
4850 | } |
4851 | ||
2b85edfc PB |
4852 | if (submitted != nr) |
4853 | percpu_ref_put_many(&ctx->refs, nr - submitted); | |
9e645e11 | 4854 | if (link) |
1b4a51b6 | 4855 | io_queue_link_head(link); |
6c271ce2 JA |
4856 | if (statep) |
4857 | io_submit_state_end(&state); | |
4858 | ||
ae9428ca PB |
4859 | /* Commit SQ ring head once we've consumed and submitted all SQEs */ |
4860 | io_commit_sqring(ctx); | |
4861 | ||
6c271ce2 JA |
4862 | return submitted; |
4863 | } | |
4864 | ||
4865 | static int io_sq_thread(void *data) | |
4866 | { | |
6c271ce2 JA |
4867 | struct io_ring_ctx *ctx = data; |
4868 | struct mm_struct *cur_mm = NULL; | |
181e448d | 4869 | const struct cred *old_cred; |
6c271ce2 JA |
4870 | mm_segment_t old_fs; |
4871 | DEFINE_WAIT(wait); | |
4872 | unsigned inflight; | |
4873 | unsigned long timeout; | |
c1edbf5f | 4874 | int ret; |
6c271ce2 | 4875 | |
206aefde | 4876 | complete(&ctx->completions[1]); |
a4c0b3de | 4877 | |
6c271ce2 JA |
4878 | old_fs = get_fs(); |
4879 | set_fs(USER_DS); | |
181e448d | 4880 | old_cred = override_creds(ctx->creds); |
6c271ce2 | 4881 | |
c1edbf5f | 4882 | ret = timeout = inflight = 0; |
2bbcd6d3 | 4883 | while (!kthread_should_park()) { |
fb5ccc98 | 4884 | unsigned int to_submit; |
6c271ce2 JA |
4885 | |
4886 | if (inflight) { | |
4887 | unsigned nr_events = 0; | |
4888 | ||
4889 | if (ctx->flags & IORING_SETUP_IOPOLL) { | |
2b2ed975 JA |
4890 | /* |
4891 | * inflight is the count of the maximum possible | |
4892 | * entries we submitted, but it can be smaller | |
4893 | * if we dropped some of them. If we don't have | |
4894 | * poll entries available, then we know that we | |
4895 | * have nothing left to poll for. Reset the | |
4896 | * inflight count to zero in that case. | |
4897 | */ | |
4898 | mutex_lock(&ctx->uring_lock); | |
4899 | if (!list_empty(&ctx->poll_list)) | |
4900 | __io_iopoll_check(ctx, &nr_events, 0); | |
4901 | else | |
4902 | inflight = 0; | |
4903 | mutex_unlock(&ctx->uring_lock); | |
6c271ce2 JA |
4904 | } else { |
4905 | /* | |
4906 | * Normal IO, just pretend everything completed. | |
4907 | * We don't have to poll completions for that. | |
4908 | */ | |
4909 | nr_events = inflight; | |
4910 | } | |
4911 | ||
4912 | inflight -= nr_events; | |
4913 | if (!inflight) | |
4914 | timeout = jiffies + ctx->sq_thread_idle; | |
4915 | } | |
4916 | ||
fb5ccc98 | 4917 | to_submit = io_sqring_entries(ctx); |
c1edbf5f JA |
4918 | |
4919 | /* | |
4920 | * If submit got -EBUSY, flag us as needing the application | |
4921 | * to enter the kernel to reap and flush events. | |
4922 | */ | |
4923 | if (!to_submit || ret == -EBUSY) { | |
6c271ce2 JA |
4924 | /* |
4925 | * We're polling. If we're within the defined idle | |
4926 | * period, then let us spin without work before going | |
c1edbf5f JA |
4927 | * to sleep. The exception is if we got EBUSY doing |
4928 | * more IO, we should wait for the application to | |
4929 | * reap events and wake us up. | |
6c271ce2 | 4930 | */ |
c1edbf5f JA |
4931 | if (inflight || |
4932 | (!time_after(jiffies, timeout) && ret != -EBUSY)) { | |
9831a90c | 4933 | cond_resched(); |
6c271ce2 JA |
4934 | continue; |
4935 | } | |
4936 | ||
4937 | /* | |
4938 | * Drop cur_mm before scheduling, we can't hold it for | |
4939 | * long periods (or over schedule()). Do this before | |
4940 | * adding ourselves to the waitqueue, as the unuse/drop | |
4941 | * may sleep. | |
4942 | */ | |
4943 | if (cur_mm) { | |
4944 | unuse_mm(cur_mm); | |
4945 | mmput(cur_mm); | |
4946 | cur_mm = NULL; | |
4947 | } | |
4948 | ||
4949 | prepare_to_wait(&ctx->sqo_wait, &wait, | |
4950 | TASK_INTERRUPTIBLE); | |
4951 | ||
4952 | /* Tell userspace we may need a wakeup call */ | |
75b28aff | 4953 | ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP; |
0d7bae69 SB |
4954 | /* make sure to read SQ tail after writing flags */ |
4955 | smp_mb(); | |
6c271ce2 | 4956 | |
fb5ccc98 | 4957 | to_submit = io_sqring_entries(ctx); |
c1edbf5f | 4958 | if (!to_submit || ret == -EBUSY) { |
2bbcd6d3 | 4959 | if (kthread_should_park()) { |
6c271ce2 JA |
4960 | finish_wait(&ctx->sqo_wait, &wait); |
4961 | break; | |
4962 | } | |
4963 | if (signal_pending(current)) | |
4964 | flush_signals(current); | |
4965 | schedule(); | |
4966 | finish_wait(&ctx->sqo_wait, &wait); | |
4967 | ||
75b28aff | 4968 | ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP; |
6c271ce2 JA |
4969 | continue; |
4970 | } | |
4971 | finish_wait(&ctx->sqo_wait, &wait); | |
4972 | ||
75b28aff | 4973 | ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP; |
6c271ce2 JA |
4974 | } |
4975 | ||
8a4955ff | 4976 | mutex_lock(&ctx->uring_lock); |
1d7bb1d5 | 4977 | ret = io_submit_sqes(ctx, to_submit, NULL, -1, &cur_mm, true); |
8a4955ff | 4978 | mutex_unlock(&ctx->uring_lock); |
1d7bb1d5 JA |
4979 | if (ret > 0) |
4980 | inflight += ret; | |
6c271ce2 JA |
4981 | } |
4982 | ||
4983 | set_fs(old_fs); | |
4984 | if (cur_mm) { | |
4985 | unuse_mm(cur_mm); | |
4986 | mmput(cur_mm); | |
4987 | } | |
181e448d | 4988 | revert_creds(old_cred); |
06058632 | 4989 | |
2bbcd6d3 | 4990 | kthread_parkme(); |
06058632 | 4991 | |
6c271ce2 JA |
4992 | return 0; |
4993 | } | |
4994 | ||
bda52162 JA |
4995 | struct io_wait_queue { |
4996 | struct wait_queue_entry wq; | |
4997 | struct io_ring_ctx *ctx; | |
4998 | unsigned to_wait; | |
4999 | unsigned nr_timeouts; | |
5000 | }; | |
5001 | ||
1d7bb1d5 | 5002 | static inline bool io_should_wake(struct io_wait_queue *iowq, bool noflush) |
bda52162 JA |
5003 | { |
5004 | struct io_ring_ctx *ctx = iowq->ctx; | |
5005 | ||
5006 | /* | |
d195a66e | 5007 | * Wake up if we have enough events, or if a timeout occurred since we |
bda52162 JA |
5008 | * started waiting. For timeouts, we always want to return to userspace, |
5009 | * regardless of event count. | |
5010 | */ | |
1d7bb1d5 | 5011 | return io_cqring_events(ctx, noflush) >= iowq->to_wait || |
bda52162 JA |
5012 | atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts; |
5013 | } | |
5014 | ||
5015 | static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, | |
5016 | int wake_flags, void *key) | |
5017 | { | |
5018 | struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue, | |
5019 | wq); | |
5020 | ||
1d7bb1d5 JA |
5021 | /* use noflush == true, as we can't safely rely on locking context */ |
5022 | if (!io_should_wake(iowq, true)) | |
bda52162 JA |
5023 | return -1; |
5024 | ||
5025 | return autoremove_wake_function(curr, mode, wake_flags, key); | |
5026 | } | |
5027 | ||
2b188cc1 JA |
5028 | /* |
5029 | * Wait until events become available, if we don't already have some. The | |
5030 | * application must reap them itself, as they reside on the shared cq ring. | |
5031 | */ | |
5032 | static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, | |
5033 | const sigset_t __user *sig, size_t sigsz) | |
5034 | { | |
bda52162 JA |
5035 | struct io_wait_queue iowq = { |
5036 | .wq = { | |
5037 | .private = current, | |
5038 | .func = io_wake_function, | |
5039 | .entry = LIST_HEAD_INIT(iowq.wq.entry), | |
5040 | }, | |
5041 | .ctx = ctx, | |
5042 | .to_wait = min_events, | |
5043 | }; | |
75b28aff | 5044 | struct io_rings *rings = ctx->rings; |
e9ffa5c2 | 5045 | int ret = 0; |
2b188cc1 | 5046 | |
1d7bb1d5 | 5047 | if (io_cqring_events(ctx, false) >= min_events) |
2b188cc1 JA |
5048 | return 0; |
5049 | ||
5050 | if (sig) { | |
9e75ad5d AB |
5051 | #ifdef CONFIG_COMPAT |
5052 | if (in_compat_syscall()) | |
5053 | ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig, | |
b772434b | 5054 | sigsz); |
9e75ad5d AB |
5055 | else |
5056 | #endif | |
b772434b | 5057 | ret = set_user_sigmask(sig, sigsz); |
9e75ad5d | 5058 | |
2b188cc1 JA |
5059 | if (ret) |
5060 | return ret; | |
5061 | } | |
5062 | ||
bda52162 | 5063 | iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts); |
c826bd7a | 5064 | trace_io_uring_cqring_wait(ctx, min_events); |
bda52162 JA |
5065 | do { |
5066 | prepare_to_wait_exclusive(&ctx->wait, &iowq.wq, | |
5067 | TASK_INTERRUPTIBLE); | |
1d7bb1d5 | 5068 | if (io_should_wake(&iowq, false)) |
bda52162 JA |
5069 | break; |
5070 | schedule(); | |
5071 | if (signal_pending(current)) { | |
e9ffa5c2 | 5072 | ret = -EINTR; |
bda52162 JA |
5073 | break; |
5074 | } | |
5075 | } while (1); | |
5076 | finish_wait(&ctx->wait, &iowq.wq); | |
5077 | ||
e9ffa5c2 | 5078 | restore_saved_sigmask_unless(ret == -EINTR); |
2b188cc1 | 5079 | |
75b28aff | 5080 | return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0; |
2b188cc1 JA |
5081 | } |
5082 | ||
6b06314c JA |
5083 | static void __io_sqe_files_unregister(struct io_ring_ctx *ctx) |
5084 | { | |
5085 | #if defined(CONFIG_UNIX) | |
5086 | if (ctx->ring_sock) { | |
5087 | struct sock *sock = ctx->ring_sock->sk; | |
5088 | struct sk_buff *skb; | |
5089 | ||
5090 | while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL) | |
5091 | kfree_skb(skb); | |
5092 | } | |
5093 | #else | |
5094 | int i; | |
5095 | ||
65e19f54 JA |
5096 | for (i = 0; i < ctx->nr_user_files; i++) { |
5097 | struct file *file; | |
5098 | ||
5099 | file = io_file_from_index(ctx, i); | |
5100 | if (file) | |
5101 | fput(file); | |
5102 | } | |
6b06314c JA |
5103 | #endif |
5104 | } | |
5105 | ||
05f3fb3c JA |
5106 | static void io_file_ref_kill(struct percpu_ref *ref) |
5107 | { | |
5108 | struct fixed_file_data *data; | |
5109 | ||
5110 | data = container_of(ref, struct fixed_file_data, refs); | |
5111 | complete(&data->done); | |
5112 | } | |
5113 | ||
6b06314c JA |
5114 | static int io_sqe_files_unregister(struct io_ring_ctx *ctx) |
5115 | { | |
05f3fb3c | 5116 | struct fixed_file_data *data = ctx->file_data; |
65e19f54 JA |
5117 | unsigned nr_tables, i; |
5118 | ||
05f3fb3c | 5119 | if (!data) |
6b06314c JA |
5120 | return -ENXIO; |
5121 | ||
05f3fb3c | 5122 | /* protect against inflight atomic switch, which drops the ref */ |
05f3fb3c | 5123 | percpu_ref_get(&data->refs); |
e46a7950 JA |
5124 | /* wait for existing switches */ |
5125 | flush_work(&data->ref_work); | |
05f3fb3c JA |
5126 | percpu_ref_kill_and_confirm(&data->refs, io_file_ref_kill); |
5127 | wait_for_completion(&data->done); | |
5128 | percpu_ref_put(&data->refs); | |
e46a7950 JA |
5129 | /* flush potential new switch */ |
5130 | flush_work(&data->ref_work); | |
05f3fb3c JA |
5131 | percpu_ref_exit(&data->refs); |
5132 | ||
6b06314c | 5133 | __io_sqe_files_unregister(ctx); |
65e19f54 JA |
5134 | nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE); |
5135 | for (i = 0; i < nr_tables; i++) | |
05f3fb3c JA |
5136 | kfree(data->table[i].files); |
5137 | kfree(data->table); | |
5138 | kfree(data); | |
5139 | ctx->file_data = NULL; | |
6b06314c JA |
5140 | ctx->nr_user_files = 0; |
5141 | return 0; | |
5142 | } | |
5143 | ||
6c271ce2 JA |
5144 | static void io_sq_thread_stop(struct io_ring_ctx *ctx) |
5145 | { | |
5146 | if (ctx->sqo_thread) { | |
206aefde | 5147 | wait_for_completion(&ctx->completions[1]); |
2bbcd6d3 RP |
5148 | /* |
5149 | * The park is a bit of a work-around, without it we get | |
5150 | * warning spews on shutdown with SQPOLL set and affinity | |
5151 | * set to a single CPU. | |
5152 | */ | |
06058632 | 5153 | kthread_park(ctx->sqo_thread); |
6c271ce2 JA |
5154 | kthread_stop(ctx->sqo_thread); |
5155 | ctx->sqo_thread = NULL; | |
5156 | } | |
5157 | } | |
5158 | ||
6b06314c JA |
5159 | static void io_finish_async(struct io_ring_ctx *ctx) |
5160 | { | |
6c271ce2 JA |
5161 | io_sq_thread_stop(ctx); |
5162 | ||
561fb04a JA |
5163 | if (ctx->io_wq) { |
5164 | io_wq_destroy(ctx->io_wq); | |
5165 | ctx->io_wq = NULL; | |
6b06314c JA |
5166 | } |
5167 | } | |
5168 | ||
5169 | #if defined(CONFIG_UNIX) | |
6b06314c JA |
5170 | /* |
5171 | * Ensure the UNIX gc is aware of our file set, so we are certain that | |
5172 | * the io_uring can be safely unregistered on process exit, even if we have | |
5173 | * loops in the file referencing. | |
5174 | */ | |
5175 | static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset) | |
5176 | { | |
5177 | struct sock *sk = ctx->ring_sock->sk; | |
5178 | struct scm_fp_list *fpl; | |
5179 | struct sk_buff *skb; | |
08a45173 | 5180 | int i, nr_files; |
6b06314c JA |
5181 | |
5182 | if (!capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN)) { | |
5183 | unsigned long inflight = ctx->user->unix_inflight + nr; | |
5184 | ||
5185 | if (inflight > task_rlimit(current, RLIMIT_NOFILE)) | |
5186 | return -EMFILE; | |
5187 | } | |
5188 | ||
5189 | fpl = kzalloc(sizeof(*fpl), GFP_KERNEL); | |
5190 | if (!fpl) | |
5191 | return -ENOMEM; | |
5192 | ||
5193 | skb = alloc_skb(0, GFP_KERNEL); | |
5194 | if (!skb) { | |
5195 | kfree(fpl); | |
5196 | return -ENOMEM; | |
5197 | } | |
5198 | ||
5199 | skb->sk = sk; | |
6b06314c | 5200 | |
08a45173 | 5201 | nr_files = 0; |
6b06314c JA |
5202 | fpl->user = get_uid(ctx->user); |
5203 | for (i = 0; i < nr; i++) { | |
65e19f54 JA |
5204 | struct file *file = io_file_from_index(ctx, i + offset); |
5205 | ||
5206 | if (!file) | |
08a45173 | 5207 | continue; |
65e19f54 | 5208 | fpl->fp[nr_files] = get_file(file); |
08a45173 JA |
5209 | unix_inflight(fpl->user, fpl->fp[nr_files]); |
5210 | nr_files++; | |
6b06314c JA |
5211 | } |
5212 | ||
08a45173 JA |
5213 | if (nr_files) { |
5214 | fpl->max = SCM_MAX_FD; | |
5215 | fpl->count = nr_files; | |
5216 | UNIXCB(skb).fp = fpl; | |
05f3fb3c | 5217 | skb->destructor = unix_destruct_scm; |
08a45173 JA |
5218 | refcount_add(skb->truesize, &sk->sk_wmem_alloc); |
5219 | skb_queue_head(&sk->sk_receive_queue, skb); | |
6b06314c | 5220 | |
08a45173 JA |
5221 | for (i = 0; i < nr_files; i++) |
5222 | fput(fpl->fp[i]); | |
5223 | } else { | |
5224 | kfree_skb(skb); | |
5225 | kfree(fpl); | |
5226 | } | |
6b06314c JA |
5227 | |
5228 | return 0; | |
5229 | } | |
5230 | ||
5231 | /* | |
5232 | * If UNIX sockets are enabled, fd passing can cause a reference cycle which | |
5233 | * causes regular reference counting to break down. We rely on the UNIX | |
5234 | * garbage collection to take care of this problem for us. | |
5235 | */ | |
5236 | static int io_sqe_files_scm(struct io_ring_ctx *ctx) | |
5237 | { | |
5238 | unsigned left, total; | |
5239 | int ret = 0; | |
5240 | ||
5241 | total = 0; | |
5242 | left = ctx->nr_user_files; | |
5243 | while (left) { | |
5244 | unsigned this_files = min_t(unsigned, left, SCM_MAX_FD); | |
6b06314c JA |
5245 | |
5246 | ret = __io_sqe_files_scm(ctx, this_files, total); | |
5247 | if (ret) | |
5248 | break; | |
5249 | left -= this_files; | |
5250 | total += this_files; | |
5251 | } | |
5252 | ||
5253 | if (!ret) | |
5254 | return 0; | |
5255 | ||
5256 | while (total < ctx->nr_user_files) { | |
65e19f54 JA |
5257 | struct file *file = io_file_from_index(ctx, total); |
5258 | ||
5259 | if (file) | |
5260 | fput(file); | |
6b06314c JA |
5261 | total++; |
5262 | } | |
5263 | ||
5264 | return ret; | |
5265 | } | |
5266 | #else | |
5267 | static int io_sqe_files_scm(struct io_ring_ctx *ctx) | |
5268 | { | |
5269 | return 0; | |
5270 | } | |
5271 | #endif | |
5272 | ||
65e19f54 JA |
5273 | static int io_sqe_alloc_file_tables(struct io_ring_ctx *ctx, unsigned nr_tables, |
5274 | unsigned nr_files) | |
5275 | { | |
5276 | int i; | |
5277 | ||
5278 | for (i = 0; i < nr_tables; i++) { | |
05f3fb3c | 5279 | struct fixed_file_table *table = &ctx->file_data->table[i]; |
65e19f54 JA |
5280 | unsigned this_files; |
5281 | ||
5282 | this_files = min(nr_files, IORING_MAX_FILES_TABLE); | |
5283 | table->files = kcalloc(this_files, sizeof(struct file *), | |
5284 | GFP_KERNEL); | |
5285 | if (!table->files) | |
5286 | break; | |
5287 | nr_files -= this_files; | |
5288 | } | |
5289 | ||
5290 | if (i == nr_tables) | |
5291 | return 0; | |
5292 | ||
5293 | for (i = 0; i < nr_tables; i++) { | |
05f3fb3c | 5294 | struct fixed_file_table *table = &ctx->file_data->table[i]; |
65e19f54 JA |
5295 | kfree(table->files); |
5296 | } | |
5297 | return 1; | |
5298 | } | |
5299 | ||
05f3fb3c JA |
5300 | static void io_ring_file_put(struct io_ring_ctx *ctx, struct file *file) |
5301 | { | |
5302 | #if defined(CONFIG_UNIX) | |
5303 | struct sock *sock = ctx->ring_sock->sk; | |
5304 | struct sk_buff_head list, *head = &sock->sk_receive_queue; | |
5305 | struct sk_buff *skb; | |
5306 | int i; | |
5307 | ||
5308 | __skb_queue_head_init(&list); | |
5309 | ||
5310 | /* | |
5311 | * Find the skb that holds this file in its SCM_RIGHTS. When found, | |
5312 | * remove this entry and rearrange the file array. | |
5313 | */ | |
5314 | skb = skb_dequeue(head); | |
5315 | while (skb) { | |
5316 | struct scm_fp_list *fp; | |
5317 | ||
5318 | fp = UNIXCB(skb).fp; | |
5319 | for (i = 0; i < fp->count; i++) { | |
5320 | int left; | |
5321 | ||
5322 | if (fp->fp[i] != file) | |
5323 | continue; | |
5324 | ||
5325 | unix_notinflight(fp->user, fp->fp[i]); | |
5326 | left = fp->count - 1 - i; | |
5327 | if (left) { | |
5328 | memmove(&fp->fp[i], &fp->fp[i + 1], | |
5329 | left * sizeof(struct file *)); | |
5330 | } | |
5331 | fp->count--; | |
5332 | if (!fp->count) { | |
5333 | kfree_skb(skb); | |
5334 | skb = NULL; | |
5335 | } else { | |
5336 | __skb_queue_tail(&list, skb); | |
5337 | } | |
5338 | fput(file); | |
5339 | file = NULL; | |
5340 | break; | |
5341 | } | |
5342 | ||
5343 | if (!file) | |
5344 | break; | |
5345 | ||
5346 | __skb_queue_tail(&list, skb); | |
5347 | ||
5348 | skb = skb_dequeue(head); | |
5349 | } | |
5350 | ||
5351 | if (skb_peek(&list)) { | |
5352 | spin_lock_irq(&head->lock); | |
5353 | while ((skb = __skb_dequeue(&list)) != NULL) | |
5354 | __skb_queue_tail(head, skb); | |
5355 | spin_unlock_irq(&head->lock); | |
5356 | } | |
5357 | #else | |
5358 | fput(file); | |
5359 | #endif | |
5360 | } | |
5361 | ||
5362 | struct io_file_put { | |
5363 | struct llist_node llist; | |
5364 | struct file *file; | |
5365 | struct completion *done; | |
5366 | }; | |
5367 | ||
5368 | static void io_ring_file_ref_switch(struct work_struct *work) | |
5369 | { | |
5370 | struct io_file_put *pfile, *tmp; | |
5371 | struct fixed_file_data *data; | |
5372 | struct llist_node *node; | |
5373 | ||
5374 | data = container_of(work, struct fixed_file_data, ref_work); | |
5375 | ||
5376 | while ((node = llist_del_all(&data->put_llist)) != NULL) { | |
5377 | llist_for_each_entry_safe(pfile, tmp, node, llist) { | |
5378 | io_ring_file_put(data->ctx, pfile->file); | |
5379 | if (pfile->done) | |
5380 | complete(pfile->done); | |
5381 | else | |
5382 | kfree(pfile); | |
5383 | } | |
5384 | } | |
5385 | ||
5386 | percpu_ref_get(&data->refs); | |
5387 | percpu_ref_switch_to_percpu(&data->refs); | |
5388 | } | |
5389 | ||
5390 | static void io_file_data_ref_zero(struct percpu_ref *ref) | |
5391 | { | |
5392 | struct fixed_file_data *data; | |
5393 | ||
5394 | data = container_of(ref, struct fixed_file_data, refs); | |
5395 | ||
5396 | /* we can't safely switch from inside this context, punt to wq */ | |
5397 | queue_work(system_wq, &data->ref_work); | |
5398 | } | |
5399 | ||
6b06314c JA |
5400 | static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, |
5401 | unsigned nr_args) | |
5402 | { | |
5403 | __s32 __user *fds = (__s32 __user *) arg; | |
65e19f54 | 5404 | unsigned nr_tables; |
05f3fb3c | 5405 | struct file *file; |
6b06314c JA |
5406 | int fd, ret = 0; |
5407 | unsigned i; | |
5408 | ||
05f3fb3c | 5409 | if (ctx->file_data) |
6b06314c JA |
5410 | return -EBUSY; |
5411 | if (!nr_args) | |
5412 | return -EINVAL; | |
5413 | if (nr_args > IORING_MAX_FIXED_FILES) | |
5414 | return -EMFILE; | |
5415 | ||
05f3fb3c JA |
5416 | ctx->file_data = kzalloc(sizeof(*ctx->file_data), GFP_KERNEL); |
5417 | if (!ctx->file_data) | |
5418 | return -ENOMEM; | |
5419 | ctx->file_data->ctx = ctx; | |
5420 | init_completion(&ctx->file_data->done); | |
5421 | ||
65e19f54 | 5422 | nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE); |
05f3fb3c JA |
5423 | ctx->file_data->table = kcalloc(nr_tables, |
5424 | sizeof(struct fixed_file_table), | |
65e19f54 | 5425 | GFP_KERNEL); |
05f3fb3c JA |
5426 | if (!ctx->file_data->table) { |
5427 | kfree(ctx->file_data); | |
5428 | ctx->file_data = NULL; | |
6b06314c | 5429 | return -ENOMEM; |
05f3fb3c JA |
5430 | } |
5431 | ||
5432 | if (percpu_ref_init(&ctx->file_data->refs, io_file_data_ref_zero, | |
5433 | PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) { | |
5434 | kfree(ctx->file_data->table); | |
5435 | kfree(ctx->file_data); | |
5436 | ctx->file_data = NULL; | |
5437 | return -ENOMEM; | |
5438 | } | |
5439 | ctx->file_data->put_llist.first = NULL; | |
5440 | INIT_WORK(&ctx->file_data->ref_work, io_ring_file_ref_switch); | |
6b06314c | 5441 | |
65e19f54 | 5442 | if (io_sqe_alloc_file_tables(ctx, nr_tables, nr_args)) { |
05f3fb3c JA |
5443 | percpu_ref_exit(&ctx->file_data->refs); |
5444 | kfree(ctx->file_data->table); | |
5445 | kfree(ctx->file_data); | |
5446 | ctx->file_data = NULL; | |
65e19f54 JA |
5447 | return -ENOMEM; |
5448 | } | |
5449 | ||
08a45173 | 5450 | for (i = 0; i < nr_args; i++, ctx->nr_user_files++) { |
65e19f54 JA |
5451 | struct fixed_file_table *table; |
5452 | unsigned index; | |
5453 | ||
6b06314c JA |
5454 | ret = -EFAULT; |
5455 | if (copy_from_user(&fd, &fds[i], sizeof(fd))) | |
5456 | break; | |
08a45173 JA |
5457 | /* allow sparse sets */ |
5458 | if (fd == -1) { | |
5459 | ret = 0; | |
5460 | continue; | |
5461 | } | |
6b06314c | 5462 | |
05f3fb3c | 5463 | table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT]; |
65e19f54 | 5464 | index = i & IORING_FILE_TABLE_MASK; |
05f3fb3c | 5465 | file = fget(fd); |
6b06314c JA |
5466 | |
5467 | ret = -EBADF; | |
05f3fb3c | 5468 | if (!file) |
6b06314c | 5469 | break; |
05f3fb3c | 5470 | |
6b06314c JA |
5471 | /* |
5472 | * Don't allow io_uring instances to be registered. If UNIX | |
5473 | * isn't enabled, then this causes a reference cycle and this | |
5474 | * instance can never get freed. If UNIX is enabled we'll | |
5475 | * handle it just fine, but there's still no point in allowing | |
5476 | * a ring fd as it doesn't support regular read/write anyway. | |
5477 | */ | |
05f3fb3c JA |
5478 | if (file->f_op == &io_uring_fops) { |
5479 | fput(file); | |
6b06314c JA |
5480 | break; |
5481 | } | |
6b06314c | 5482 | ret = 0; |
05f3fb3c | 5483 | table->files[index] = file; |
6b06314c JA |
5484 | } |
5485 | ||
5486 | if (ret) { | |
65e19f54 | 5487 | for (i = 0; i < ctx->nr_user_files; i++) { |
65e19f54 JA |
5488 | file = io_file_from_index(ctx, i); |
5489 | if (file) | |
5490 | fput(file); | |
5491 | } | |
5492 | for (i = 0; i < nr_tables; i++) | |
05f3fb3c | 5493 | kfree(ctx->file_data->table[i].files); |
6b06314c | 5494 | |
05f3fb3c JA |
5495 | kfree(ctx->file_data->table); |
5496 | kfree(ctx->file_data); | |
5497 | ctx->file_data = NULL; | |
6b06314c JA |
5498 | ctx->nr_user_files = 0; |
5499 | return ret; | |
5500 | } | |
5501 | ||
5502 | ret = io_sqe_files_scm(ctx); | |
5503 | if (ret) | |
5504 | io_sqe_files_unregister(ctx); | |
5505 | ||
5506 | return ret; | |
5507 | } | |
5508 | ||
c3a31e60 JA |
5509 | static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file, |
5510 | int index) | |
5511 | { | |
5512 | #if defined(CONFIG_UNIX) | |
5513 | struct sock *sock = ctx->ring_sock->sk; | |
5514 | struct sk_buff_head *head = &sock->sk_receive_queue; | |
5515 | struct sk_buff *skb; | |
5516 | ||
5517 | /* | |
5518 | * See if we can merge this file into an existing skb SCM_RIGHTS | |
5519 | * file set. If there's no room, fall back to allocating a new skb | |
5520 | * and filling it in. | |
5521 | */ | |
5522 | spin_lock_irq(&head->lock); | |
5523 | skb = skb_peek(head); | |
5524 | if (skb) { | |
5525 | struct scm_fp_list *fpl = UNIXCB(skb).fp; | |
5526 | ||
5527 | if (fpl->count < SCM_MAX_FD) { | |
5528 | __skb_unlink(skb, head); | |
5529 | spin_unlock_irq(&head->lock); | |
5530 | fpl->fp[fpl->count] = get_file(file); | |
5531 | unix_inflight(fpl->user, fpl->fp[fpl->count]); | |
5532 | fpl->count++; | |
5533 | spin_lock_irq(&head->lock); | |
5534 | __skb_queue_head(head, skb); | |
5535 | } else { | |
5536 | skb = NULL; | |
5537 | } | |
5538 | } | |
5539 | spin_unlock_irq(&head->lock); | |
5540 | ||
5541 | if (skb) { | |
5542 | fput(file); | |
5543 | return 0; | |
5544 | } | |
5545 | ||
5546 | return __io_sqe_files_scm(ctx, 1, index); | |
5547 | #else | |
5548 | return 0; | |
5549 | #endif | |
5550 | } | |
5551 | ||
05f3fb3c | 5552 | static void io_atomic_switch(struct percpu_ref *ref) |
c3a31e60 | 5553 | { |
05f3fb3c JA |
5554 | struct fixed_file_data *data; |
5555 | ||
5556 | data = container_of(ref, struct fixed_file_data, refs); | |
5557 | clear_bit(FFD_F_ATOMIC, &data->state); | |
5558 | } | |
5559 | ||
5560 | static bool io_queue_file_removal(struct fixed_file_data *data, | |
5561 | struct file *file) | |
5562 | { | |
5563 | struct io_file_put *pfile, pfile_stack; | |
5564 | DECLARE_COMPLETION_ONSTACK(done); | |
5565 | ||
5566 | /* | |
5567 | * If we fail allocating the struct we need for doing async reomval | |
5568 | * of this file, just punt to sync and wait for it. | |
5569 | */ | |
5570 | pfile = kzalloc(sizeof(*pfile), GFP_KERNEL); | |
5571 | if (!pfile) { | |
5572 | pfile = &pfile_stack; | |
5573 | pfile->done = &done; | |
5574 | } | |
5575 | ||
5576 | pfile->file = file; | |
5577 | llist_add(&pfile->llist, &data->put_llist); | |
5578 | ||
5579 | if (pfile == &pfile_stack) { | |
5580 | if (!test_and_set_bit(FFD_F_ATOMIC, &data->state)) { | |
5581 | percpu_ref_put(&data->refs); | |
5582 | percpu_ref_switch_to_atomic(&data->refs, | |
5583 | io_atomic_switch); | |
5584 | } | |
5585 | wait_for_completion(&done); | |
5586 | flush_work(&data->ref_work); | |
5587 | return false; | |
5588 | } | |
5589 | ||
5590 | return true; | |
5591 | } | |
5592 | ||
5593 | static int __io_sqe_files_update(struct io_ring_ctx *ctx, | |
5594 | struct io_uring_files_update *up, | |
5595 | unsigned nr_args) | |
5596 | { | |
5597 | struct fixed_file_data *data = ctx->file_data; | |
5598 | bool ref_switch = false; | |
5599 | struct file *file; | |
c3a31e60 JA |
5600 | __s32 __user *fds; |
5601 | int fd, i, err; | |
5602 | __u32 done; | |
5603 | ||
05f3fb3c | 5604 | if (check_add_overflow(up->offset, nr_args, &done)) |
c3a31e60 JA |
5605 | return -EOVERFLOW; |
5606 | if (done > ctx->nr_user_files) | |
5607 | return -EINVAL; | |
5608 | ||
5609 | done = 0; | |
05f3fb3c | 5610 | fds = u64_to_user_ptr(up->fds); |
c3a31e60 | 5611 | while (nr_args) { |
65e19f54 JA |
5612 | struct fixed_file_table *table; |
5613 | unsigned index; | |
5614 | ||
c3a31e60 JA |
5615 | err = 0; |
5616 | if (copy_from_user(&fd, &fds[done], sizeof(fd))) { | |
5617 | err = -EFAULT; | |
5618 | break; | |
5619 | } | |
05f3fb3c JA |
5620 | i = array_index_nospec(up->offset, ctx->nr_user_files); |
5621 | table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT]; | |
65e19f54 JA |
5622 | index = i & IORING_FILE_TABLE_MASK; |
5623 | if (table->files[index]) { | |
05f3fb3c | 5624 | file = io_file_from_index(ctx, index); |
65e19f54 | 5625 | table->files[index] = NULL; |
05f3fb3c JA |
5626 | if (io_queue_file_removal(data, file)) |
5627 | ref_switch = true; | |
c3a31e60 JA |
5628 | } |
5629 | if (fd != -1) { | |
c3a31e60 JA |
5630 | file = fget(fd); |
5631 | if (!file) { | |
5632 | err = -EBADF; | |
5633 | break; | |
5634 | } | |
5635 | /* | |
5636 | * Don't allow io_uring instances to be registered. If | |
5637 | * UNIX isn't enabled, then this causes a reference | |
5638 | * cycle and this instance can never get freed. If UNIX | |
5639 | * is enabled we'll handle it just fine, but there's | |
5640 | * still no point in allowing a ring fd as it doesn't | |
5641 | * support regular read/write anyway. | |
5642 | */ | |
5643 | if (file->f_op == &io_uring_fops) { | |
5644 | fput(file); | |
5645 | err = -EBADF; | |
5646 | break; | |
5647 | } | |
65e19f54 | 5648 | table->files[index] = file; |
c3a31e60 JA |
5649 | err = io_sqe_file_register(ctx, file, i); |
5650 | if (err) | |
5651 | break; | |
5652 | } | |
5653 | nr_args--; | |
5654 | done++; | |
05f3fb3c JA |
5655 | up->offset++; |
5656 | } | |
5657 | ||
5658 | if (ref_switch && !test_and_set_bit(FFD_F_ATOMIC, &data->state)) { | |
5659 | percpu_ref_put(&data->refs); | |
5660 | percpu_ref_switch_to_atomic(&data->refs, io_atomic_switch); | |
c3a31e60 JA |
5661 | } |
5662 | ||
5663 | return done ? done : err; | |
5664 | } | |
05f3fb3c JA |
5665 | static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg, |
5666 | unsigned nr_args) | |
5667 | { | |
5668 | struct io_uring_files_update up; | |
5669 | ||
5670 | if (!ctx->file_data) | |
5671 | return -ENXIO; | |
5672 | if (!nr_args) | |
5673 | return -EINVAL; | |
5674 | if (copy_from_user(&up, arg, sizeof(up))) | |
5675 | return -EFAULT; | |
5676 | if (up.resv) | |
5677 | return -EINVAL; | |
5678 | ||
5679 | return __io_sqe_files_update(ctx, &up, nr_args); | |
5680 | } | |
c3a31e60 | 5681 | |
7d723065 JA |
5682 | static void io_put_work(struct io_wq_work *work) |
5683 | { | |
5684 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); | |
5685 | ||
5686 | io_put_req(req); | |
5687 | } | |
5688 | ||
5689 | static void io_get_work(struct io_wq_work *work) | |
5690 | { | |
5691 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); | |
5692 | ||
5693 | refcount_inc(&req->refs); | |
5694 | } | |
5695 | ||
6c271ce2 JA |
5696 | static int io_sq_offload_start(struct io_ring_ctx *ctx, |
5697 | struct io_uring_params *p) | |
2b188cc1 | 5698 | { |
576a347b | 5699 | struct io_wq_data data; |
561fb04a | 5700 | unsigned concurrency; |
2b188cc1 JA |
5701 | int ret; |
5702 | ||
6c271ce2 | 5703 | init_waitqueue_head(&ctx->sqo_wait); |
2b188cc1 JA |
5704 | mmgrab(current->mm); |
5705 | ctx->sqo_mm = current->mm; | |
5706 | ||
6c271ce2 | 5707 | if (ctx->flags & IORING_SETUP_SQPOLL) { |
3ec482d1 JA |
5708 | ret = -EPERM; |
5709 | if (!capable(CAP_SYS_ADMIN)) | |
5710 | goto err; | |
5711 | ||
917257da JA |
5712 | ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle); |
5713 | if (!ctx->sq_thread_idle) | |
5714 | ctx->sq_thread_idle = HZ; | |
5715 | ||
6c271ce2 | 5716 | if (p->flags & IORING_SETUP_SQ_AFF) { |
44a9bd18 | 5717 | int cpu = p->sq_thread_cpu; |
6c271ce2 | 5718 | |
917257da | 5719 | ret = -EINVAL; |
44a9bd18 JA |
5720 | if (cpu >= nr_cpu_ids) |
5721 | goto err; | |
7889f44d | 5722 | if (!cpu_online(cpu)) |
917257da JA |
5723 | goto err; |
5724 | ||
6c271ce2 JA |
5725 | ctx->sqo_thread = kthread_create_on_cpu(io_sq_thread, |
5726 | ctx, cpu, | |
5727 | "io_uring-sq"); | |
5728 | } else { | |
5729 | ctx->sqo_thread = kthread_create(io_sq_thread, ctx, | |
5730 | "io_uring-sq"); | |
5731 | } | |
5732 | if (IS_ERR(ctx->sqo_thread)) { | |
5733 | ret = PTR_ERR(ctx->sqo_thread); | |
5734 | ctx->sqo_thread = NULL; | |
5735 | goto err; | |
5736 | } | |
5737 | wake_up_process(ctx->sqo_thread); | |
5738 | } else if (p->flags & IORING_SETUP_SQ_AFF) { | |
5739 | /* Can't have SQ_AFF without SQPOLL */ | |
5740 | ret = -EINVAL; | |
5741 | goto err; | |
5742 | } | |
5743 | ||
576a347b JA |
5744 | data.mm = ctx->sqo_mm; |
5745 | data.user = ctx->user; | |
181e448d | 5746 | data.creds = ctx->creds; |
576a347b JA |
5747 | data.get_work = io_get_work; |
5748 | data.put_work = io_put_work; | |
5749 | ||
561fb04a JA |
5750 | /* Do QD, or 4 * CPUS, whatever is smallest */ |
5751 | concurrency = min(ctx->sq_entries, 4 * num_online_cpus()); | |
576a347b | 5752 | ctx->io_wq = io_wq_create(concurrency, &data); |
975c99a5 JA |
5753 | if (IS_ERR(ctx->io_wq)) { |
5754 | ret = PTR_ERR(ctx->io_wq); | |
5755 | ctx->io_wq = NULL; | |
2b188cc1 JA |
5756 | goto err; |
5757 | } | |
5758 | ||
5759 | return 0; | |
5760 | err: | |
54a91f3b | 5761 | io_finish_async(ctx); |
2b188cc1 JA |
5762 | mmdrop(ctx->sqo_mm); |
5763 | ctx->sqo_mm = NULL; | |
5764 | return ret; | |
5765 | } | |
5766 | ||
5767 | static void io_unaccount_mem(struct user_struct *user, unsigned long nr_pages) | |
5768 | { | |
5769 | atomic_long_sub(nr_pages, &user->locked_vm); | |
5770 | } | |
5771 | ||
5772 | static int io_account_mem(struct user_struct *user, unsigned long nr_pages) | |
5773 | { | |
5774 | unsigned long page_limit, cur_pages, new_pages; | |
5775 | ||
5776 | /* Don't allow more pages than we can safely lock */ | |
5777 | page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; | |
5778 | ||
5779 | do { | |
5780 | cur_pages = atomic_long_read(&user->locked_vm); | |
5781 | new_pages = cur_pages + nr_pages; | |
5782 | if (new_pages > page_limit) | |
5783 | return -ENOMEM; | |
5784 | } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages, | |
5785 | new_pages) != cur_pages); | |
5786 | ||
5787 | return 0; | |
5788 | } | |
5789 | ||
5790 | static void io_mem_free(void *ptr) | |
5791 | { | |
52e04ef4 MR |
5792 | struct page *page; |
5793 | ||
5794 | if (!ptr) | |
5795 | return; | |
2b188cc1 | 5796 | |
52e04ef4 | 5797 | page = virt_to_head_page(ptr); |
2b188cc1 JA |
5798 | if (put_page_testzero(page)) |
5799 | free_compound_page(page); | |
5800 | } | |
5801 | ||
5802 | static void *io_mem_alloc(size_t size) | |
5803 | { | |
5804 | gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP | | |
5805 | __GFP_NORETRY; | |
5806 | ||
5807 | return (void *) __get_free_pages(gfp_flags, get_order(size)); | |
5808 | } | |
5809 | ||
75b28aff HV |
5810 | static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries, |
5811 | size_t *sq_offset) | |
5812 | { | |
5813 | struct io_rings *rings; | |
5814 | size_t off, sq_array_size; | |
5815 | ||
5816 | off = struct_size(rings, cqes, cq_entries); | |
5817 | if (off == SIZE_MAX) | |
5818 | return SIZE_MAX; | |
5819 | ||
5820 | #ifdef CONFIG_SMP | |
5821 | off = ALIGN(off, SMP_CACHE_BYTES); | |
5822 | if (off == 0) | |
5823 | return SIZE_MAX; | |
5824 | #endif | |
5825 | ||
5826 | sq_array_size = array_size(sizeof(u32), sq_entries); | |
5827 | if (sq_array_size == SIZE_MAX) | |
5828 | return SIZE_MAX; | |
5829 | ||
5830 | if (check_add_overflow(off, sq_array_size, &off)) | |
5831 | return SIZE_MAX; | |
5832 | ||
5833 | if (sq_offset) | |
5834 | *sq_offset = off; | |
5835 | ||
5836 | return off; | |
5837 | } | |
5838 | ||
2b188cc1 JA |
5839 | static unsigned long ring_pages(unsigned sq_entries, unsigned cq_entries) |
5840 | { | |
75b28aff | 5841 | size_t pages; |
2b188cc1 | 5842 | |
75b28aff HV |
5843 | pages = (size_t)1 << get_order( |
5844 | rings_size(sq_entries, cq_entries, NULL)); | |
5845 | pages += (size_t)1 << get_order( | |
5846 | array_size(sizeof(struct io_uring_sqe), sq_entries)); | |
2b188cc1 | 5847 | |
75b28aff | 5848 | return pages; |
2b188cc1 JA |
5849 | } |
5850 | ||
edafccee JA |
5851 | static int io_sqe_buffer_unregister(struct io_ring_ctx *ctx) |
5852 | { | |
5853 | int i, j; | |
5854 | ||
5855 | if (!ctx->user_bufs) | |
5856 | return -ENXIO; | |
5857 | ||
5858 | for (i = 0; i < ctx->nr_user_bufs; i++) { | |
5859 | struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; | |
5860 | ||
5861 | for (j = 0; j < imu->nr_bvecs; j++) | |
27c4d3a3 | 5862 | put_user_page(imu->bvec[j].bv_page); |
edafccee JA |
5863 | |
5864 | if (ctx->account_mem) | |
5865 | io_unaccount_mem(ctx->user, imu->nr_bvecs); | |
d4ef6475 | 5866 | kvfree(imu->bvec); |
edafccee JA |
5867 | imu->nr_bvecs = 0; |
5868 | } | |
5869 | ||
5870 | kfree(ctx->user_bufs); | |
5871 | ctx->user_bufs = NULL; | |
5872 | ctx->nr_user_bufs = 0; | |
5873 | return 0; | |
5874 | } | |
5875 | ||
5876 | static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, | |
5877 | void __user *arg, unsigned index) | |
5878 | { | |
5879 | struct iovec __user *src; | |
5880 | ||
5881 | #ifdef CONFIG_COMPAT | |
5882 | if (ctx->compat) { | |
5883 | struct compat_iovec __user *ciovs; | |
5884 | struct compat_iovec ciov; | |
5885 | ||
5886 | ciovs = (struct compat_iovec __user *) arg; | |
5887 | if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov))) | |
5888 | return -EFAULT; | |
5889 | ||
d55e5f5b | 5890 | dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base); |
edafccee JA |
5891 | dst->iov_len = ciov.iov_len; |
5892 | return 0; | |
5893 | } | |
5894 | #endif | |
5895 | src = (struct iovec __user *) arg; | |
5896 | if (copy_from_user(dst, &src[index], sizeof(*dst))) | |
5897 | return -EFAULT; | |
5898 | return 0; | |
5899 | } | |
5900 | ||
5901 | static int io_sqe_buffer_register(struct io_ring_ctx *ctx, void __user *arg, | |
5902 | unsigned nr_args) | |
5903 | { | |
5904 | struct vm_area_struct **vmas = NULL; | |
5905 | struct page **pages = NULL; | |
5906 | int i, j, got_pages = 0; | |
5907 | int ret = -EINVAL; | |
5908 | ||
5909 | if (ctx->user_bufs) | |
5910 | return -EBUSY; | |
5911 | if (!nr_args || nr_args > UIO_MAXIOV) | |
5912 | return -EINVAL; | |
5913 | ||
5914 | ctx->user_bufs = kcalloc(nr_args, sizeof(struct io_mapped_ubuf), | |
5915 | GFP_KERNEL); | |
5916 | if (!ctx->user_bufs) | |
5917 | return -ENOMEM; | |
5918 | ||
5919 | for (i = 0; i < nr_args; i++) { | |
5920 | struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; | |
5921 | unsigned long off, start, end, ubuf; | |
5922 | int pret, nr_pages; | |
5923 | struct iovec iov; | |
5924 | size_t size; | |
5925 | ||
5926 | ret = io_copy_iov(ctx, &iov, arg, i); | |
5927 | if (ret) | |
a278682d | 5928 | goto err; |
edafccee JA |
5929 | |
5930 | /* | |
5931 | * Don't impose further limits on the size and buffer | |
5932 | * constraints here, we'll -EINVAL later when IO is | |
5933 | * submitted if they are wrong. | |
5934 | */ | |
5935 | ret = -EFAULT; | |
5936 | if (!iov.iov_base || !iov.iov_len) | |
5937 | goto err; | |
5938 | ||
5939 | /* arbitrary limit, but we need something */ | |
5940 | if (iov.iov_len > SZ_1G) | |
5941 | goto err; | |
5942 | ||
5943 | ubuf = (unsigned long) iov.iov_base; | |
5944 | end = (ubuf + iov.iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
5945 | start = ubuf >> PAGE_SHIFT; | |
5946 | nr_pages = end - start; | |
5947 | ||
5948 | if (ctx->account_mem) { | |
5949 | ret = io_account_mem(ctx->user, nr_pages); | |
5950 | if (ret) | |
5951 | goto err; | |
5952 | } | |
5953 | ||
5954 | ret = 0; | |
5955 | if (!pages || nr_pages > got_pages) { | |
5956 | kfree(vmas); | |
5957 | kfree(pages); | |
d4ef6475 | 5958 | pages = kvmalloc_array(nr_pages, sizeof(struct page *), |
edafccee | 5959 | GFP_KERNEL); |
d4ef6475 | 5960 | vmas = kvmalloc_array(nr_pages, |
edafccee JA |
5961 | sizeof(struct vm_area_struct *), |
5962 | GFP_KERNEL); | |
5963 | if (!pages || !vmas) { | |
5964 | ret = -ENOMEM; | |
5965 | if (ctx->account_mem) | |
5966 | io_unaccount_mem(ctx->user, nr_pages); | |
5967 | goto err; | |
5968 | } | |
5969 | got_pages = nr_pages; | |
5970 | } | |
5971 | ||
d4ef6475 | 5972 | imu->bvec = kvmalloc_array(nr_pages, sizeof(struct bio_vec), |
edafccee JA |
5973 | GFP_KERNEL); |
5974 | ret = -ENOMEM; | |
5975 | if (!imu->bvec) { | |
5976 | if (ctx->account_mem) | |
5977 | io_unaccount_mem(ctx->user, nr_pages); | |
5978 | goto err; | |
5979 | } | |
5980 | ||
5981 | ret = 0; | |
5982 | down_read(¤t->mm->mmap_sem); | |
932f4a63 IW |
5983 | pret = get_user_pages(ubuf, nr_pages, |
5984 | FOLL_WRITE | FOLL_LONGTERM, | |
5985 | pages, vmas); | |
edafccee JA |
5986 | if (pret == nr_pages) { |
5987 | /* don't support file backed memory */ | |
5988 | for (j = 0; j < nr_pages; j++) { | |
5989 | struct vm_area_struct *vma = vmas[j]; | |
5990 | ||
5991 | if (vma->vm_file && | |
5992 | !is_file_hugepages(vma->vm_file)) { | |
5993 | ret = -EOPNOTSUPP; | |
5994 | break; | |
5995 | } | |
5996 | } | |
5997 | } else { | |
5998 | ret = pret < 0 ? pret : -EFAULT; | |
5999 | } | |
6000 | up_read(¤t->mm->mmap_sem); | |
6001 | if (ret) { | |
6002 | /* | |
6003 | * if we did partial map, or found file backed vmas, | |
6004 | * release any pages we did get | |
6005 | */ | |
27c4d3a3 JH |
6006 | if (pret > 0) |
6007 | put_user_pages(pages, pret); | |
edafccee JA |
6008 | if (ctx->account_mem) |
6009 | io_unaccount_mem(ctx->user, nr_pages); | |
d4ef6475 | 6010 | kvfree(imu->bvec); |
edafccee JA |
6011 | goto err; |
6012 | } | |
6013 | ||
6014 | off = ubuf & ~PAGE_MASK; | |
6015 | size = iov.iov_len; | |
6016 | for (j = 0; j < nr_pages; j++) { | |
6017 | size_t vec_len; | |
6018 | ||
6019 | vec_len = min_t(size_t, size, PAGE_SIZE - off); | |
6020 | imu->bvec[j].bv_page = pages[j]; | |
6021 | imu->bvec[j].bv_len = vec_len; | |
6022 | imu->bvec[j].bv_offset = off; | |
6023 | off = 0; | |
6024 | size -= vec_len; | |
6025 | } | |
6026 | /* store original address for later verification */ | |
6027 | imu->ubuf = ubuf; | |
6028 | imu->len = iov.iov_len; | |
6029 | imu->nr_bvecs = nr_pages; | |
6030 | ||
6031 | ctx->nr_user_bufs++; | |
6032 | } | |
d4ef6475 MR |
6033 | kvfree(pages); |
6034 | kvfree(vmas); | |
edafccee JA |
6035 | return 0; |
6036 | err: | |
d4ef6475 MR |
6037 | kvfree(pages); |
6038 | kvfree(vmas); | |
edafccee JA |
6039 | io_sqe_buffer_unregister(ctx); |
6040 | return ret; | |
6041 | } | |
6042 | ||
9b402849 JA |
6043 | static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg) |
6044 | { | |
6045 | __s32 __user *fds = arg; | |
6046 | int fd; | |
6047 | ||
6048 | if (ctx->cq_ev_fd) | |
6049 | return -EBUSY; | |
6050 | ||
6051 | if (copy_from_user(&fd, fds, sizeof(*fds))) | |
6052 | return -EFAULT; | |
6053 | ||
6054 | ctx->cq_ev_fd = eventfd_ctx_fdget(fd); | |
6055 | if (IS_ERR(ctx->cq_ev_fd)) { | |
6056 | int ret = PTR_ERR(ctx->cq_ev_fd); | |
6057 | ctx->cq_ev_fd = NULL; | |
6058 | return ret; | |
6059 | } | |
6060 | ||
6061 | return 0; | |
6062 | } | |
6063 | ||
6064 | static int io_eventfd_unregister(struct io_ring_ctx *ctx) | |
6065 | { | |
6066 | if (ctx->cq_ev_fd) { | |
6067 | eventfd_ctx_put(ctx->cq_ev_fd); | |
6068 | ctx->cq_ev_fd = NULL; | |
6069 | return 0; | |
6070 | } | |
6071 | ||
6072 | return -ENXIO; | |
6073 | } | |
6074 | ||
2b188cc1 JA |
6075 | static void io_ring_ctx_free(struct io_ring_ctx *ctx) |
6076 | { | |
6b06314c | 6077 | io_finish_async(ctx); |
2b188cc1 JA |
6078 | if (ctx->sqo_mm) |
6079 | mmdrop(ctx->sqo_mm); | |
def596e9 JA |
6080 | |
6081 | io_iopoll_reap_events(ctx); | |
edafccee | 6082 | io_sqe_buffer_unregister(ctx); |
6b06314c | 6083 | io_sqe_files_unregister(ctx); |
9b402849 | 6084 | io_eventfd_unregister(ctx); |
def596e9 | 6085 | |
2b188cc1 | 6086 | #if defined(CONFIG_UNIX) |
355e8d26 EB |
6087 | if (ctx->ring_sock) { |
6088 | ctx->ring_sock->file = NULL; /* so that iput() is called */ | |
2b188cc1 | 6089 | sock_release(ctx->ring_sock); |
355e8d26 | 6090 | } |
2b188cc1 JA |
6091 | #endif |
6092 | ||
75b28aff | 6093 | io_mem_free(ctx->rings); |
2b188cc1 | 6094 | io_mem_free(ctx->sq_sqes); |
2b188cc1 JA |
6095 | |
6096 | percpu_ref_exit(&ctx->refs); | |
6097 | if (ctx->account_mem) | |
6098 | io_unaccount_mem(ctx->user, | |
6099 | ring_pages(ctx->sq_entries, ctx->cq_entries)); | |
6100 | free_uid(ctx->user); | |
181e448d | 6101 | put_cred(ctx->creds); |
206aefde | 6102 | kfree(ctx->completions); |
78076bb6 | 6103 | kfree(ctx->cancel_hash); |
0ddf92e8 | 6104 | kmem_cache_free(req_cachep, ctx->fallback_req); |
2b188cc1 JA |
6105 | kfree(ctx); |
6106 | } | |
6107 | ||
6108 | static __poll_t io_uring_poll(struct file *file, poll_table *wait) | |
6109 | { | |
6110 | struct io_ring_ctx *ctx = file->private_data; | |
6111 | __poll_t mask = 0; | |
6112 | ||
6113 | poll_wait(file, &ctx->cq_wait, wait); | |
4f7067c3 SB |
6114 | /* |
6115 | * synchronizes with barrier from wq_has_sleeper call in | |
6116 | * io_commit_cqring | |
6117 | */ | |
2b188cc1 | 6118 | smp_rmb(); |
75b28aff HV |
6119 | if (READ_ONCE(ctx->rings->sq.tail) - ctx->cached_sq_head != |
6120 | ctx->rings->sq_ring_entries) | |
2b188cc1 | 6121 | mask |= EPOLLOUT | EPOLLWRNORM; |
daa5de54 | 6122 | if (READ_ONCE(ctx->rings->cq.head) != ctx->cached_cq_tail) |
2b188cc1 JA |
6123 | mask |= EPOLLIN | EPOLLRDNORM; |
6124 | ||
6125 | return mask; | |
6126 | } | |
6127 | ||
6128 | static int io_uring_fasync(int fd, struct file *file, int on) | |
6129 | { | |
6130 | struct io_ring_ctx *ctx = file->private_data; | |
6131 | ||
6132 | return fasync_helper(fd, file, on, &ctx->cq_fasync); | |
6133 | } | |
6134 | ||
6135 | static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) | |
6136 | { | |
6137 | mutex_lock(&ctx->uring_lock); | |
6138 | percpu_ref_kill(&ctx->refs); | |
6139 | mutex_unlock(&ctx->uring_lock); | |
6140 | ||
5262f567 | 6141 | io_kill_timeouts(ctx); |
221c5eb2 | 6142 | io_poll_remove_all(ctx); |
561fb04a JA |
6143 | |
6144 | if (ctx->io_wq) | |
6145 | io_wq_cancel_all(ctx->io_wq); | |
6146 | ||
def596e9 | 6147 | io_iopoll_reap_events(ctx); |
15dff286 JA |
6148 | /* if we failed setting up the ctx, we might not have any rings */ |
6149 | if (ctx->rings) | |
6150 | io_cqring_overflow_flush(ctx, true); | |
206aefde | 6151 | wait_for_completion(&ctx->completions[0]); |
2b188cc1 JA |
6152 | io_ring_ctx_free(ctx); |
6153 | } | |
6154 | ||
6155 | static int io_uring_release(struct inode *inode, struct file *file) | |
6156 | { | |
6157 | struct io_ring_ctx *ctx = file->private_data; | |
6158 | ||
6159 | file->private_data = NULL; | |
6160 | io_ring_ctx_wait_and_kill(ctx); | |
6161 | return 0; | |
6162 | } | |
6163 | ||
fcb323cc JA |
6164 | static void io_uring_cancel_files(struct io_ring_ctx *ctx, |
6165 | struct files_struct *files) | |
6166 | { | |
6167 | struct io_kiocb *req; | |
6168 | DEFINE_WAIT(wait); | |
6169 | ||
6170 | while (!list_empty_careful(&ctx->inflight_list)) { | |
768134d4 | 6171 | struct io_kiocb *cancel_req = NULL; |
fcb323cc JA |
6172 | |
6173 | spin_lock_irq(&ctx->inflight_lock); | |
6174 | list_for_each_entry(req, &ctx->inflight_list, inflight_entry) { | |
768134d4 JA |
6175 | if (req->work.files != files) |
6176 | continue; | |
6177 | /* req is being completed, ignore */ | |
6178 | if (!refcount_inc_not_zero(&req->refs)) | |
6179 | continue; | |
6180 | cancel_req = req; | |
6181 | break; | |
fcb323cc | 6182 | } |
768134d4 | 6183 | if (cancel_req) |
fcb323cc | 6184 | prepare_to_wait(&ctx->inflight_wait, &wait, |
768134d4 | 6185 | TASK_UNINTERRUPTIBLE); |
fcb323cc JA |
6186 | spin_unlock_irq(&ctx->inflight_lock); |
6187 | ||
768134d4 JA |
6188 | /* We need to keep going until we don't find a matching req */ |
6189 | if (!cancel_req) | |
fcb323cc | 6190 | break; |
2f6d9b9d BL |
6191 | |
6192 | io_wq_cancel_work(ctx->io_wq, &cancel_req->work); | |
6193 | io_put_req(cancel_req); | |
fcb323cc JA |
6194 | schedule(); |
6195 | } | |
768134d4 | 6196 | finish_wait(&ctx->inflight_wait, &wait); |
fcb323cc JA |
6197 | } |
6198 | ||
6199 | static int io_uring_flush(struct file *file, void *data) | |
6200 | { | |
6201 | struct io_ring_ctx *ctx = file->private_data; | |
6202 | ||
6203 | io_uring_cancel_files(ctx, data); | |
1d7bb1d5 JA |
6204 | if (fatal_signal_pending(current) || (current->flags & PF_EXITING)) { |
6205 | io_cqring_overflow_flush(ctx, true); | |
fcb323cc | 6206 | io_wq_cancel_all(ctx->io_wq); |
1d7bb1d5 | 6207 | } |
fcb323cc JA |
6208 | return 0; |
6209 | } | |
6210 | ||
6c5c240e RP |
6211 | static void *io_uring_validate_mmap_request(struct file *file, |
6212 | loff_t pgoff, size_t sz) | |
2b188cc1 | 6213 | { |
2b188cc1 | 6214 | struct io_ring_ctx *ctx = file->private_data; |
6c5c240e | 6215 | loff_t offset = pgoff << PAGE_SHIFT; |
2b188cc1 JA |
6216 | struct page *page; |
6217 | void *ptr; | |
6218 | ||
6219 | switch (offset) { | |
6220 | case IORING_OFF_SQ_RING: | |
75b28aff HV |
6221 | case IORING_OFF_CQ_RING: |
6222 | ptr = ctx->rings; | |
2b188cc1 JA |
6223 | break; |
6224 | case IORING_OFF_SQES: | |
6225 | ptr = ctx->sq_sqes; | |
6226 | break; | |
2b188cc1 | 6227 | default: |
6c5c240e | 6228 | return ERR_PTR(-EINVAL); |
2b188cc1 JA |
6229 | } |
6230 | ||
6231 | page = virt_to_head_page(ptr); | |
a50b854e | 6232 | if (sz > page_size(page)) |
6c5c240e RP |
6233 | return ERR_PTR(-EINVAL); |
6234 | ||
6235 | return ptr; | |
6236 | } | |
6237 | ||
6238 | #ifdef CONFIG_MMU | |
6239 | ||
6240 | static int io_uring_mmap(struct file *file, struct vm_area_struct *vma) | |
6241 | { | |
6242 | size_t sz = vma->vm_end - vma->vm_start; | |
6243 | unsigned long pfn; | |
6244 | void *ptr; | |
6245 | ||
6246 | ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz); | |
6247 | if (IS_ERR(ptr)) | |
6248 | return PTR_ERR(ptr); | |
2b188cc1 JA |
6249 | |
6250 | pfn = virt_to_phys(ptr) >> PAGE_SHIFT; | |
6251 | return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot); | |
6252 | } | |
6253 | ||
6c5c240e RP |
6254 | #else /* !CONFIG_MMU */ |
6255 | ||
6256 | static int io_uring_mmap(struct file *file, struct vm_area_struct *vma) | |
6257 | { | |
6258 | return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL; | |
6259 | } | |
6260 | ||
6261 | static unsigned int io_uring_nommu_mmap_capabilities(struct file *file) | |
6262 | { | |
6263 | return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE; | |
6264 | } | |
6265 | ||
6266 | static unsigned long io_uring_nommu_get_unmapped_area(struct file *file, | |
6267 | unsigned long addr, unsigned long len, | |
6268 | unsigned long pgoff, unsigned long flags) | |
6269 | { | |
6270 | void *ptr; | |
6271 | ||
6272 | ptr = io_uring_validate_mmap_request(file, pgoff, len); | |
6273 | if (IS_ERR(ptr)) | |
6274 | return PTR_ERR(ptr); | |
6275 | ||
6276 | return (unsigned long) ptr; | |
6277 | } | |
6278 | ||
6279 | #endif /* !CONFIG_MMU */ | |
6280 | ||
2b188cc1 JA |
6281 | SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, |
6282 | u32, min_complete, u32, flags, const sigset_t __user *, sig, | |
6283 | size_t, sigsz) | |
6284 | { | |
6285 | struct io_ring_ctx *ctx; | |
6286 | long ret = -EBADF; | |
6287 | int submitted = 0; | |
6288 | struct fd f; | |
6289 | ||
6c271ce2 | 6290 | if (flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP)) |
2b188cc1 JA |
6291 | return -EINVAL; |
6292 | ||
6293 | f = fdget(fd); | |
6294 | if (!f.file) | |
6295 | return -EBADF; | |
6296 | ||
6297 | ret = -EOPNOTSUPP; | |
6298 | if (f.file->f_op != &io_uring_fops) | |
6299 | goto out_fput; | |
6300 | ||
6301 | ret = -ENXIO; | |
6302 | ctx = f.file->private_data; | |
6303 | if (!percpu_ref_tryget(&ctx->refs)) | |
6304 | goto out_fput; | |
6305 | ||
6c271ce2 JA |
6306 | /* |
6307 | * For SQ polling, the thread will do all submissions and completions. | |
6308 | * Just return the requested submit count, and wake the thread if | |
6309 | * we were asked to. | |
6310 | */ | |
b2a9eada | 6311 | ret = 0; |
6c271ce2 | 6312 | if (ctx->flags & IORING_SETUP_SQPOLL) { |
c1edbf5f JA |
6313 | if (!list_empty_careful(&ctx->cq_overflow_list)) |
6314 | io_cqring_overflow_flush(ctx, false); | |
6c271ce2 JA |
6315 | if (flags & IORING_ENTER_SQ_WAKEUP) |
6316 | wake_up(&ctx->sqo_wait); | |
6317 | submitted = to_submit; | |
b2a9eada | 6318 | } else if (to_submit) { |
ae9428ca | 6319 | struct mm_struct *cur_mm; |
2b188cc1 | 6320 | |
44d28279 JA |
6321 | if (current->mm != ctx->sqo_mm || |
6322 | current_cred() != ctx->creds) { | |
6323 | ret = -EPERM; | |
6324 | goto out; | |
6325 | } | |
6326 | ||
2b188cc1 | 6327 | mutex_lock(&ctx->uring_lock); |
ae9428ca PB |
6328 | /* already have mm, so io_submit_sqes() won't try to grab it */ |
6329 | cur_mm = ctx->sqo_mm; | |
6330 | submitted = io_submit_sqes(ctx, to_submit, f.file, fd, | |
6331 | &cur_mm, false); | |
2b188cc1 | 6332 | mutex_unlock(&ctx->uring_lock); |
7c504e65 PB |
6333 | |
6334 | if (submitted != to_submit) | |
6335 | goto out; | |
2b188cc1 JA |
6336 | } |
6337 | if (flags & IORING_ENTER_GETEVENTS) { | |
def596e9 JA |
6338 | unsigned nr_events = 0; |
6339 | ||
2b188cc1 JA |
6340 | min_complete = min(min_complete, ctx->cq_entries); |
6341 | ||
def596e9 | 6342 | if (ctx->flags & IORING_SETUP_IOPOLL) { |
def596e9 | 6343 | ret = io_iopoll_check(ctx, &nr_events, min_complete); |
def596e9 JA |
6344 | } else { |
6345 | ret = io_cqring_wait(ctx, min_complete, sig, sigsz); | |
6346 | } | |
2b188cc1 JA |
6347 | } |
6348 | ||
7c504e65 | 6349 | out: |
6805b32e | 6350 | percpu_ref_put(&ctx->refs); |
2b188cc1 JA |
6351 | out_fput: |
6352 | fdput(f); | |
6353 | return submitted ? submitted : ret; | |
6354 | } | |
6355 | ||
6356 | static const struct file_operations io_uring_fops = { | |
6357 | .release = io_uring_release, | |
fcb323cc | 6358 | .flush = io_uring_flush, |
2b188cc1 | 6359 | .mmap = io_uring_mmap, |
6c5c240e RP |
6360 | #ifndef CONFIG_MMU |
6361 | .get_unmapped_area = io_uring_nommu_get_unmapped_area, | |
6362 | .mmap_capabilities = io_uring_nommu_mmap_capabilities, | |
6363 | #endif | |
2b188cc1 JA |
6364 | .poll = io_uring_poll, |
6365 | .fasync = io_uring_fasync, | |
6366 | }; | |
6367 | ||
6368 | static int io_allocate_scq_urings(struct io_ring_ctx *ctx, | |
6369 | struct io_uring_params *p) | |
6370 | { | |
75b28aff HV |
6371 | struct io_rings *rings; |
6372 | size_t size, sq_array_offset; | |
2b188cc1 | 6373 | |
75b28aff HV |
6374 | size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset); |
6375 | if (size == SIZE_MAX) | |
6376 | return -EOVERFLOW; | |
6377 | ||
6378 | rings = io_mem_alloc(size); | |
6379 | if (!rings) | |
2b188cc1 JA |
6380 | return -ENOMEM; |
6381 | ||
75b28aff HV |
6382 | ctx->rings = rings; |
6383 | ctx->sq_array = (u32 *)((char *)rings + sq_array_offset); | |
6384 | rings->sq_ring_mask = p->sq_entries - 1; | |
6385 | rings->cq_ring_mask = p->cq_entries - 1; | |
6386 | rings->sq_ring_entries = p->sq_entries; | |
6387 | rings->cq_ring_entries = p->cq_entries; | |
6388 | ctx->sq_mask = rings->sq_ring_mask; | |
6389 | ctx->cq_mask = rings->cq_ring_mask; | |
6390 | ctx->sq_entries = rings->sq_ring_entries; | |
6391 | ctx->cq_entries = rings->cq_ring_entries; | |
2b188cc1 JA |
6392 | |
6393 | size = array_size(sizeof(struct io_uring_sqe), p->sq_entries); | |
eb065d30 JA |
6394 | if (size == SIZE_MAX) { |
6395 | io_mem_free(ctx->rings); | |
6396 | ctx->rings = NULL; | |
2b188cc1 | 6397 | return -EOVERFLOW; |
eb065d30 | 6398 | } |
2b188cc1 JA |
6399 | |
6400 | ctx->sq_sqes = io_mem_alloc(size); | |
eb065d30 JA |
6401 | if (!ctx->sq_sqes) { |
6402 | io_mem_free(ctx->rings); | |
6403 | ctx->rings = NULL; | |
2b188cc1 | 6404 | return -ENOMEM; |
eb065d30 | 6405 | } |
2b188cc1 | 6406 | |
2b188cc1 JA |
6407 | return 0; |
6408 | } | |
6409 | ||
6410 | /* | |
6411 | * Allocate an anonymous fd, this is what constitutes the application | |
6412 | * visible backing of an io_uring instance. The application mmaps this | |
6413 | * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled, | |
6414 | * we have to tie this fd to a socket for file garbage collection purposes. | |
6415 | */ | |
6416 | static int io_uring_get_fd(struct io_ring_ctx *ctx) | |
6417 | { | |
6418 | struct file *file; | |
6419 | int ret; | |
6420 | ||
6421 | #if defined(CONFIG_UNIX) | |
6422 | ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP, | |
6423 | &ctx->ring_sock); | |
6424 | if (ret) | |
6425 | return ret; | |
6426 | #endif | |
6427 | ||
6428 | ret = get_unused_fd_flags(O_RDWR | O_CLOEXEC); | |
6429 | if (ret < 0) | |
6430 | goto err; | |
6431 | ||
6432 | file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx, | |
6433 | O_RDWR | O_CLOEXEC); | |
6434 | if (IS_ERR(file)) { | |
6435 | put_unused_fd(ret); | |
6436 | ret = PTR_ERR(file); | |
6437 | goto err; | |
6438 | } | |
6439 | ||
6440 | #if defined(CONFIG_UNIX) | |
6441 | ctx->ring_sock->file = file; | |
6442 | #endif | |
6443 | fd_install(ret, file); | |
6444 | return ret; | |
6445 | err: | |
6446 | #if defined(CONFIG_UNIX) | |
6447 | sock_release(ctx->ring_sock); | |
6448 | ctx->ring_sock = NULL; | |
6449 | #endif | |
6450 | return ret; | |
6451 | } | |
6452 | ||
6453 | static int io_uring_create(unsigned entries, struct io_uring_params *p) | |
6454 | { | |
6455 | struct user_struct *user = NULL; | |
6456 | struct io_ring_ctx *ctx; | |
6457 | bool account_mem; | |
6458 | int ret; | |
6459 | ||
8110c1a6 | 6460 | if (!entries) |
2b188cc1 | 6461 | return -EINVAL; |
8110c1a6 JA |
6462 | if (entries > IORING_MAX_ENTRIES) { |
6463 | if (!(p->flags & IORING_SETUP_CLAMP)) | |
6464 | return -EINVAL; | |
6465 | entries = IORING_MAX_ENTRIES; | |
6466 | } | |
2b188cc1 JA |
6467 | |
6468 | /* | |
6469 | * Use twice as many entries for the CQ ring. It's possible for the | |
6470 | * application to drive a higher depth than the size of the SQ ring, | |
6471 | * since the sqes are only used at submission time. This allows for | |
33a107f0 JA |
6472 | * some flexibility in overcommitting a bit. If the application has |
6473 | * set IORING_SETUP_CQSIZE, it will have passed in the desired number | |
6474 | * of CQ ring entries manually. | |
2b188cc1 JA |
6475 | */ |
6476 | p->sq_entries = roundup_pow_of_two(entries); | |
33a107f0 JA |
6477 | if (p->flags & IORING_SETUP_CQSIZE) { |
6478 | /* | |
6479 | * If IORING_SETUP_CQSIZE is set, we do the same roundup | |
6480 | * to a power-of-two, if it isn't already. We do NOT impose | |
6481 | * any cq vs sq ring sizing. | |
6482 | */ | |
8110c1a6 | 6483 | if (p->cq_entries < p->sq_entries) |
33a107f0 | 6484 | return -EINVAL; |
8110c1a6 JA |
6485 | if (p->cq_entries > IORING_MAX_CQ_ENTRIES) { |
6486 | if (!(p->flags & IORING_SETUP_CLAMP)) | |
6487 | return -EINVAL; | |
6488 | p->cq_entries = IORING_MAX_CQ_ENTRIES; | |
6489 | } | |
33a107f0 JA |
6490 | p->cq_entries = roundup_pow_of_two(p->cq_entries); |
6491 | } else { | |
6492 | p->cq_entries = 2 * p->sq_entries; | |
6493 | } | |
2b188cc1 JA |
6494 | |
6495 | user = get_uid(current_user()); | |
6496 | account_mem = !capable(CAP_IPC_LOCK); | |
6497 | ||
6498 | if (account_mem) { | |
6499 | ret = io_account_mem(user, | |
6500 | ring_pages(p->sq_entries, p->cq_entries)); | |
6501 | if (ret) { | |
6502 | free_uid(user); | |
6503 | return ret; | |
6504 | } | |
6505 | } | |
6506 | ||
6507 | ctx = io_ring_ctx_alloc(p); | |
6508 | if (!ctx) { | |
6509 | if (account_mem) | |
6510 | io_unaccount_mem(user, ring_pages(p->sq_entries, | |
6511 | p->cq_entries)); | |
6512 | free_uid(user); | |
6513 | return -ENOMEM; | |
6514 | } | |
6515 | ctx->compat = in_compat_syscall(); | |
6516 | ctx->account_mem = account_mem; | |
6517 | ctx->user = user; | |
0b8c0ec7 | 6518 | ctx->creds = get_current_cred(); |
2b188cc1 JA |
6519 | |
6520 | ret = io_allocate_scq_urings(ctx, p); | |
6521 | if (ret) | |
6522 | goto err; | |
6523 | ||
6c271ce2 | 6524 | ret = io_sq_offload_start(ctx, p); |
2b188cc1 JA |
6525 | if (ret) |
6526 | goto err; | |
6527 | ||
2b188cc1 | 6528 | memset(&p->sq_off, 0, sizeof(p->sq_off)); |
75b28aff HV |
6529 | p->sq_off.head = offsetof(struct io_rings, sq.head); |
6530 | p->sq_off.tail = offsetof(struct io_rings, sq.tail); | |
6531 | p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask); | |
6532 | p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries); | |
6533 | p->sq_off.flags = offsetof(struct io_rings, sq_flags); | |
6534 | p->sq_off.dropped = offsetof(struct io_rings, sq_dropped); | |
6535 | p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings; | |
2b188cc1 JA |
6536 | |
6537 | memset(&p->cq_off, 0, sizeof(p->cq_off)); | |
75b28aff HV |
6538 | p->cq_off.head = offsetof(struct io_rings, cq.head); |
6539 | p->cq_off.tail = offsetof(struct io_rings, cq.tail); | |
6540 | p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask); | |
6541 | p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries); | |
6542 | p->cq_off.overflow = offsetof(struct io_rings, cq_overflow); | |
6543 | p->cq_off.cqes = offsetof(struct io_rings, cqes); | |
ac90f249 | 6544 | |
044c1ab3 JA |
6545 | /* |
6546 | * Install ring fd as the very last thing, so we don't risk someone | |
6547 | * having closed it before we finish setup | |
6548 | */ | |
6549 | ret = io_uring_get_fd(ctx); | |
6550 | if (ret < 0) | |
6551 | goto err; | |
6552 | ||
da8c9690 | 6553 | p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP | |
ba04291e | 6554 | IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS; |
c826bd7a | 6555 | trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags); |
2b188cc1 JA |
6556 | return ret; |
6557 | err: | |
6558 | io_ring_ctx_wait_and_kill(ctx); | |
6559 | return ret; | |
6560 | } | |
6561 | ||
6562 | /* | |
6563 | * Sets up an aio uring context, and returns the fd. Applications asks for a | |
6564 | * ring size, we return the actual sq/cq ring sizes (among other things) in the | |
6565 | * params structure passed in. | |
6566 | */ | |
6567 | static long io_uring_setup(u32 entries, struct io_uring_params __user *params) | |
6568 | { | |
6569 | struct io_uring_params p; | |
6570 | long ret; | |
6571 | int i; | |
6572 | ||
6573 | if (copy_from_user(&p, params, sizeof(p))) | |
6574 | return -EFAULT; | |
6575 | for (i = 0; i < ARRAY_SIZE(p.resv); i++) { | |
6576 | if (p.resv[i]) | |
6577 | return -EINVAL; | |
6578 | } | |
6579 | ||
6c271ce2 | 6580 | if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL | |
8110c1a6 JA |
6581 | IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE | |
6582 | IORING_SETUP_CLAMP)) | |
2b188cc1 JA |
6583 | return -EINVAL; |
6584 | ||
6585 | ret = io_uring_create(entries, &p); | |
6586 | if (ret < 0) | |
6587 | return ret; | |
6588 | ||
6589 | if (copy_to_user(params, &p, sizeof(p))) | |
6590 | return -EFAULT; | |
6591 | ||
6592 | return ret; | |
6593 | } | |
6594 | ||
6595 | SYSCALL_DEFINE2(io_uring_setup, u32, entries, | |
6596 | struct io_uring_params __user *, params) | |
6597 | { | |
6598 | return io_uring_setup(entries, params); | |
6599 | } | |
6600 | ||
66f4af93 JA |
6601 | static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args) |
6602 | { | |
6603 | struct io_uring_probe *p; | |
6604 | size_t size; | |
6605 | int i, ret; | |
6606 | ||
6607 | size = struct_size(p, ops, nr_args); | |
6608 | if (size == SIZE_MAX) | |
6609 | return -EOVERFLOW; | |
6610 | p = kzalloc(size, GFP_KERNEL); | |
6611 | if (!p) | |
6612 | return -ENOMEM; | |
6613 | ||
6614 | ret = -EFAULT; | |
6615 | if (copy_from_user(p, arg, size)) | |
6616 | goto out; | |
6617 | ret = -EINVAL; | |
6618 | if (memchr_inv(p, 0, size)) | |
6619 | goto out; | |
6620 | ||
6621 | p->last_op = IORING_OP_LAST - 1; | |
6622 | if (nr_args > IORING_OP_LAST) | |
6623 | nr_args = IORING_OP_LAST; | |
6624 | ||
6625 | for (i = 0; i < nr_args; i++) { | |
6626 | p->ops[i].op = i; | |
6627 | if (!io_op_defs[i].not_supported) | |
6628 | p->ops[i].flags = IO_URING_OP_SUPPORTED; | |
6629 | } | |
6630 | p->ops_len = i; | |
6631 | ||
6632 | ret = 0; | |
6633 | if (copy_to_user(arg, p, size)) | |
6634 | ret = -EFAULT; | |
6635 | out: | |
6636 | kfree(p); | |
6637 | return ret; | |
6638 | } | |
6639 | ||
edafccee JA |
6640 | static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, |
6641 | void __user *arg, unsigned nr_args) | |
b19062a5 JA |
6642 | __releases(ctx->uring_lock) |
6643 | __acquires(ctx->uring_lock) | |
edafccee JA |
6644 | { |
6645 | int ret; | |
6646 | ||
35fa71a0 JA |
6647 | /* |
6648 | * We're inside the ring mutex, if the ref is already dying, then | |
6649 | * someone else killed the ctx or is already going through | |
6650 | * io_uring_register(). | |
6651 | */ | |
6652 | if (percpu_ref_is_dying(&ctx->refs)) | |
6653 | return -ENXIO; | |
6654 | ||
05f3fb3c | 6655 | if (opcode != IORING_UNREGISTER_FILES && |
66f4af93 JA |
6656 | opcode != IORING_REGISTER_FILES_UPDATE && |
6657 | opcode != IORING_REGISTER_PROBE) { | |
05f3fb3c | 6658 | percpu_ref_kill(&ctx->refs); |
b19062a5 | 6659 | |
05f3fb3c JA |
6660 | /* |
6661 | * Drop uring mutex before waiting for references to exit. If | |
6662 | * another thread is currently inside io_uring_enter() it might | |
6663 | * need to grab the uring_lock to make progress. If we hold it | |
6664 | * here across the drain wait, then we can deadlock. It's safe | |
6665 | * to drop the mutex here, since no new references will come in | |
6666 | * after we've killed the percpu ref. | |
6667 | */ | |
6668 | mutex_unlock(&ctx->uring_lock); | |
c150368b | 6669 | ret = wait_for_completion_interruptible(&ctx->completions[0]); |
05f3fb3c | 6670 | mutex_lock(&ctx->uring_lock); |
c150368b JA |
6671 | if (ret) { |
6672 | percpu_ref_resurrect(&ctx->refs); | |
6673 | ret = -EINTR; | |
6674 | goto out; | |
6675 | } | |
05f3fb3c | 6676 | } |
edafccee JA |
6677 | |
6678 | switch (opcode) { | |
6679 | case IORING_REGISTER_BUFFERS: | |
6680 | ret = io_sqe_buffer_register(ctx, arg, nr_args); | |
6681 | break; | |
6682 | case IORING_UNREGISTER_BUFFERS: | |
6683 | ret = -EINVAL; | |
6684 | if (arg || nr_args) | |
6685 | break; | |
6686 | ret = io_sqe_buffer_unregister(ctx); | |
6687 | break; | |
6b06314c JA |
6688 | case IORING_REGISTER_FILES: |
6689 | ret = io_sqe_files_register(ctx, arg, nr_args); | |
6690 | break; | |
6691 | case IORING_UNREGISTER_FILES: | |
6692 | ret = -EINVAL; | |
6693 | if (arg || nr_args) | |
6694 | break; | |
6695 | ret = io_sqe_files_unregister(ctx); | |
6696 | break; | |
c3a31e60 JA |
6697 | case IORING_REGISTER_FILES_UPDATE: |
6698 | ret = io_sqe_files_update(ctx, arg, nr_args); | |
6699 | break; | |
9b402849 | 6700 | case IORING_REGISTER_EVENTFD: |
f2842ab5 | 6701 | case IORING_REGISTER_EVENTFD_ASYNC: |
9b402849 JA |
6702 | ret = -EINVAL; |
6703 | if (nr_args != 1) | |
6704 | break; | |
6705 | ret = io_eventfd_register(ctx, arg); | |
f2842ab5 JA |
6706 | if (ret) |
6707 | break; | |
6708 | if (opcode == IORING_REGISTER_EVENTFD_ASYNC) | |
6709 | ctx->eventfd_async = 1; | |
6710 | else | |
6711 | ctx->eventfd_async = 0; | |
9b402849 JA |
6712 | break; |
6713 | case IORING_UNREGISTER_EVENTFD: | |
6714 | ret = -EINVAL; | |
6715 | if (arg || nr_args) | |
6716 | break; | |
6717 | ret = io_eventfd_unregister(ctx); | |
6718 | break; | |
66f4af93 JA |
6719 | case IORING_REGISTER_PROBE: |
6720 | ret = -EINVAL; | |
6721 | if (!arg || nr_args > 256) | |
6722 | break; | |
6723 | ret = io_probe(ctx, arg, nr_args); | |
6724 | break; | |
edafccee JA |
6725 | default: |
6726 | ret = -EINVAL; | |
6727 | break; | |
6728 | } | |
6729 | ||
05f3fb3c JA |
6730 | |
6731 | if (opcode != IORING_UNREGISTER_FILES && | |
66f4af93 JA |
6732 | opcode != IORING_REGISTER_FILES_UPDATE && |
6733 | opcode != IORING_REGISTER_PROBE) { | |
05f3fb3c | 6734 | /* bring the ctx back to life */ |
05f3fb3c | 6735 | percpu_ref_reinit(&ctx->refs); |
c150368b JA |
6736 | out: |
6737 | reinit_completion(&ctx->completions[0]); | |
05f3fb3c | 6738 | } |
edafccee JA |
6739 | return ret; |
6740 | } | |
6741 | ||
6742 | SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode, | |
6743 | void __user *, arg, unsigned int, nr_args) | |
6744 | { | |
6745 | struct io_ring_ctx *ctx; | |
6746 | long ret = -EBADF; | |
6747 | struct fd f; | |
6748 | ||
6749 | f = fdget(fd); | |
6750 | if (!f.file) | |
6751 | return -EBADF; | |
6752 | ||
6753 | ret = -EOPNOTSUPP; | |
6754 | if (f.file->f_op != &io_uring_fops) | |
6755 | goto out_fput; | |
6756 | ||
6757 | ctx = f.file->private_data; | |
6758 | ||
6759 | mutex_lock(&ctx->uring_lock); | |
6760 | ret = __io_uring_register(ctx, opcode, arg, nr_args); | |
6761 | mutex_unlock(&ctx->uring_lock); | |
c826bd7a DD |
6762 | trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs, |
6763 | ctx->cq_ev_fd != NULL, ret); | |
edafccee JA |
6764 | out_fput: |
6765 | fdput(f); | |
6766 | return ret; | |
6767 | } | |
6768 | ||
2b188cc1 JA |
6769 | static int __init io_uring_init(void) |
6770 | { | |
d3656344 | 6771 | BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST); |
2b188cc1 JA |
6772 | req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC); |
6773 | return 0; | |
6774 | }; | |
6775 | __initcall(io_uring_init); |