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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> | |
49 | ||
50 | #include <linux/sched/signal.h> | |
51 | #include <linux/fs.h> | |
52 | #include <linux/file.h> | |
53 | #include <linux/fdtable.h> | |
54 | #include <linux/mm.h> | |
55 | #include <linux/mman.h> | |
56 | #include <linux/mmu_context.h> | |
57 | #include <linux/percpu.h> | |
58 | #include <linux/slab.h> | |
6c271ce2 | 59 | #include <linux/kthread.h> |
2b188cc1 | 60 | #include <linux/blkdev.h> |
edafccee | 61 | #include <linux/bvec.h> |
2b188cc1 JA |
62 | #include <linux/net.h> |
63 | #include <net/sock.h> | |
64 | #include <net/af_unix.h> | |
6b06314c | 65 | #include <net/scm.h> |
2b188cc1 JA |
66 | #include <linux/anon_inodes.h> |
67 | #include <linux/sched/mm.h> | |
68 | #include <linux/uaccess.h> | |
69 | #include <linux/nospec.h> | |
edafccee JA |
70 | #include <linux/sizes.h> |
71 | #include <linux/hugetlb.h> | |
aa4c3967 | 72 | #include <linux/highmem.h> |
15b71abe JA |
73 | #include <linux/namei.h> |
74 | #include <linux/fsnotify.h> | |
2b188cc1 | 75 | |
c826bd7a DD |
76 | #define CREATE_TRACE_POINTS |
77 | #include <trace/events/io_uring.h> | |
78 | ||
2b188cc1 JA |
79 | #include <uapi/linux/io_uring.h> |
80 | ||
81 | #include "internal.h" | |
561fb04a | 82 | #include "io-wq.h" |
2b188cc1 | 83 | |
5277deaa | 84 | #define IORING_MAX_ENTRIES 32768 |
33a107f0 | 85 | #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES) |
65e19f54 JA |
86 | |
87 | /* | |
88 | * Shift of 9 is 512 entries, or exactly one page on 64-bit archs | |
89 | */ | |
90 | #define IORING_FILE_TABLE_SHIFT 9 | |
91 | #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT) | |
92 | #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1) | |
93 | #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE) | |
2b188cc1 JA |
94 | |
95 | struct io_uring { | |
96 | u32 head ____cacheline_aligned_in_smp; | |
97 | u32 tail ____cacheline_aligned_in_smp; | |
98 | }; | |
99 | ||
1e84b97b | 100 | /* |
75b28aff HV |
101 | * This data is shared with the application through the mmap at offsets |
102 | * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING. | |
1e84b97b SB |
103 | * |
104 | * The offsets to the member fields are published through struct | |
105 | * io_sqring_offsets when calling io_uring_setup. | |
106 | */ | |
75b28aff | 107 | struct io_rings { |
1e84b97b SB |
108 | /* |
109 | * Head and tail offsets into the ring; the offsets need to be | |
110 | * masked to get valid indices. | |
111 | * | |
75b28aff HV |
112 | * The kernel controls head of the sq ring and the tail of the cq ring, |
113 | * and the application controls tail of the sq ring and the head of the | |
114 | * cq ring. | |
1e84b97b | 115 | */ |
75b28aff | 116 | struct io_uring sq, cq; |
1e84b97b | 117 | /* |
75b28aff | 118 | * Bitmasks to apply to head and tail offsets (constant, equals |
1e84b97b SB |
119 | * ring_entries - 1) |
120 | */ | |
75b28aff HV |
121 | u32 sq_ring_mask, cq_ring_mask; |
122 | /* Ring sizes (constant, power of 2) */ | |
123 | u32 sq_ring_entries, cq_ring_entries; | |
1e84b97b SB |
124 | /* |
125 | * Number of invalid entries dropped by the kernel due to | |
126 | * invalid index stored in array | |
127 | * | |
128 | * Written by the kernel, shouldn't be modified by the | |
129 | * application (i.e. get number of "new events" by comparing to | |
130 | * cached value). | |
131 | * | |
132 | * After a new SQ head value was read by the application this | |
133 | * counter includes all submissions that were dropped reaching | |
134 | * the new SQ head (and possibly more). | |
135 | */ | |
75b28aff | 136 | u32 sq_dropped; |
1e84b97b SB |
137 | /* |
138 | * Runtime flags | |
139 | * | |
140 | * Written by the kernel, shouldn't be modified by the | |
141 | * application. | |
142 | * | |
143 | * The application needs a full memory barrier before checking | |
144 | * for IORING_SQ_NEED_WAKEUP after updating the sq tail. | |
145 | */ | |
75b28aff | 146 | u32 sq_flags; |
1e84b97b SB |
147 | /* |
148 | * Number of completion events lost because the queue was full; | |
149 | * this should be avoided by the application by making sure | |
0b4295b5 | 150 | * there are not more requests pending than there is space in |
1e84b97b SB |
151 | * the completion queue. |
152 | * | |
153 | * Written by the kernel, shouldn't be modified by the | |
154 | * application (i.e. get number of "new events" by comparing to | |
155 | * cached value). | |
156 | * | |
157 | * As completion events come in out of order this counter is not | |
158 | * ordered with any other data. | |
159 | */ | |
75b28aff | 160 | u32 cq_overflow; |
1e84b97b SB |
161 | /* |
162 | * Ring buffer of completion events. | |
163 | * | |
164 | * The kernel writes completion events fresh every time they are | |
165 | * produced, so the application is allowed to modify pending | |
166 | * entries. | |
167 | */ | |
75b28aff | 168 | struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp; |
2b188cc1 JA |
169 | }; |
170 | ||
edafccee JA |
171 | struct io_mapped_ubuf { |
172 | u64 ubuf; | |
173 | size_t len; | |
174 | struct bio_vec *bvec; | |
175 | unsigned int nr_bvecs; | |
176 | }; | |
177 | ||
65e19f54 JA |
178 | struct fixed_file_table { |
179 | struct file **files; | |
31b51510 JA |
180 | }; |
181 | ||
05f3fb3c JA |
182 | enum { |
183 | FFD_F_ATOMIC, | |
184 | }; | |
185 | ||
186 | struct fixed_file_data { | |
187 | struct fixed_file_table *table; | |
188 | struct io_ring_ctx *ctx; | |
189 | ||
190 | struct percpu_ref refs; | |
191 | struct llist_head put_llist; | |
192 | unsigned long state; | |
193 | struct work_struct ref_work; | |
194 | struct completion done; | |
195 | }; | |
196 | ||
2b188cc1 JA |
197 | struct io_ring_ctx { |
198 | struct { | |
199 | struct percpu_ref refs; | |
200 | } ____cacheline_aligned_in_smp; | |
201 | ||
202 | struct { | |
203 | unsigned int flags; | |
204 | bool compat; | |
205 | bool account_mem; | |
1d7bb1d5 | 206 | bool cq_overflow_flushed; |
1b4a51b6 | 207 | bool drain_next; |
2b188cc1 | 208 | |
75b28aff HV |
209 | /* |
210 | * Ring buffer of indices into array of io_uring_sqe, which is | |
211 | * mmapped by the application using the IORING_OFF_SQES offset. | |
212 | * | |
213 | * This indirection could e.g. be used to assign fixed | |
214 | * io_uring_sqe entries to operations and only submit them to | |
215 | * the queue when needed. | |
216 | * | |
217 | * The kernel modifies neither the indices array nor the entries | |
218 | * array. | |
219 | */ | |
220 | u32 *sq_array; | |
2b188cc1 JA |
221 | unsigned cached_sq_head; |
222 | unsigned sq_entries; | |
223 | unsigned sq_mask; | |
6c271ce2 | 224 | unsigned sq_thread_idle; |
498ccd9e | 225 | unsigned cached_sq_dropped; |
206aefde | 226 | atomic_t cached_cq_overflow; |
2b188cc1 | 227 | struct io_uring_sqe *sq_sqes; |
de0617e4 JA |
228 | |
229 | struct list_head defer_list; | |
5262f567 | 230 | struct list_head timeout_list; |
1d7bb1d5 | 231 | struct list_head cq_overflow_list; |
fcb323cc JA |
232 | |
233 | wait_queue_head_t inflight_wait; | |
2b188cc1 JA |
234 | } ____cacheline_aligned_in_smp; |
235 | ||
206aefde JA |
236 | struct io_rings *rings; |
237 | ||
2b188cc1 | 238 | /* IO offload */ |
561fb04a | 239 | struct io_wq *io_wq; |
6c271ce2 | 240 | struct task_struct *sqo_thread; /* if using sq thread polling */ |
2b188cc1 | 241 | struct mm_struct *sqo_mm; |
6c271ce2 | 242 | wait_queue_head_t sqo_wait; |
75b28aff | 243 | |
6b06314c JA |
244 | /* |
245 | * If used, fixed file set. Writers must ensure that ->refs is dead, | |
246 | * readers must ensure that ->refs is alive as long as the file* is | |
247 | * used. Only updated through io_uring_register(2). | |
248 | */ | |
05f3fb3c | 249 | struct fixed_file_data *file_data; |
6b06314c JA |
250 | unsigned nr_user_files; |
251 | ||
edafccee JA |
252 | /* if used, fixed mapped user buffers */ |
253 | unsigned nr_user_bufs; | |
254 | struct io_mapped_ubuf *user_bufs; | |
255 | ||
2b188cc1 JA |
256 | struct user_struct *user; |
257 | ||
0b8c0ec7 | 258 | const struct cred *creds; |
181e448d | 259 | |
206aefde JA |
260 | /* 0 is for ctx quiesce/reinit/free, 1 is for sqo_thread started */ |
261 | struct completion *completions; | |
262 | ||
0ddf92e8 JA |
263 | /* if all else fails... */ |
264 | struct io_kiocb *fallback_req; | |
265 | ||
206aefde JA |
266 | #if defined(CONFIG_UNIX) |
267 | struct socket *ring_sock; | |
268 | #endif | |
269 | ||
270 | struct { | |
271 | unsigned cached_cq_tail; | |
272 | unsigned cq_entries; | |
273 | unsigned cq_mask; | |
274 | atomic_t cq_timeouts; | |
275 | struct wait_queue_head cq_wait; | |
276 | struct fasync_struct *cq_fasync; | |
277 | struct eventfd_ctx *cq_ev_fd; | |
278 | } ____cacheline_aligned_in_smp; | |
2b188cc1 JA |
279 | |
280 | struct { | |
281 | struct mutex uring_lock; | |
282 | wait_queue_head_t wait; | |
283 | } ____cacheline_aligned_in_smp; | |
284 | ||
285 | struct { | |
286 | spinlock_t completion_lock; | |
def596e9 JA |
287 | bool poll_multi_file; |
288 | /* | |
289 | * ->poll_list is protected by the ctx->uring_lock for | |
290 | * io_uring instances that don't use IORING_SETUP_SQPOLL. | |
291 | * For SQPOLL, only the single threaded io_sq_thread() will | |
292 | * manipulate the list, hence no extra locking is needed there. | |
293 | */ | |
294 | struct list_head poll_list; | |
78076bb6 JA |
295 | struct hlist_head *cancel_hash; |
296 | unsigned cancel_hash_bits; | |
31b51510 | 297 | |
fcb323cc JA |
298 | spinlock_t inflight_lock; |
299 | struct list_head inflight_list; | |
2b188cc1 | 300 | } ____cacheline_aligned_in_smp; |
2b188cc1 JA |
301 | }; |
302 | ||
09bb8394 JA |
303 | /* |
304 | * First field must be the file pointer in all the | |
305 | * iocb unions! See also 'struct kiocb' in <linux/fs.h> | |
306 | */ | |
221c5eb2 JA |
307 | struct io_poll_iocb { |
308 | struct file *file; | |
0969e783 JA |
309 | union { |
310 | struct wait_queue_head *head; | |
311 | u64 addr; | |
312 | }; | |
221c5eb2 | 313 | __poll_t events; |
8c838788 | 314 | bool done; |
221c5eb2 | 315 | bool canceled; |
392edb45 | 316 | struct wait_queue_entry wait; |
221c5eb2 JA |
317 | }; |
318 | ||
b5dba59e JA |
319 | struct io_close { |
320 | struct file *file; | |
321 | struct file *put_file; | |
322 | int fd; | |
323 | }; | |
324 | ||
ad8a48ac JA |
325 | struct io_timeout_data { |
326 | struct io_kiocb *req; | |
327 | struct hrtimer timer; | |
328 | struct timespec64 ts; | |
329 | enum hrtimer_mode mode; | |
cc42e0ac | 330 | u32 seq_offset; |
ad8a48ac JA |
331 | }; |
332 | ||
8ed8d3c3 JA |
333 | struct io_accept { |
334 | struct file *file; | |
335 | struct sockaddr __user *addr; | |
336 | int __user *addr_len; | |
337 | int flags; | |
338 | }; | |
339 | ||
340 | struct io_sync { | |
341 | struct file *file; | |
342 | loff_t len; | |
343 | loff_t off; | |
344 | int flags; | |
d63d1b5e | 345 | int mode; |
8ed8d3c3 JA |
346 | }; |
347 | ||
fbf23849 JA |
348 | struct io_cancel { |
349 | struct file *file; | |
350 | u64 addr; | |
351 | }; | |
352 | ||
b29472ee JA |
353 | struct io_timeout { |
354 | struct file *file; | |
355 | u64 addr; | |
356 | int flags; | |
26a61679 | 357 | unsigned count; |
b29472ee JA |
358 | }; |
359 | ||
9adbd45d JA |
360 | struct io_rw { |
361 | /* NOTE: kiocb has the file as the first member, so don't do it here */ | |
362 | struct kiocb kiocb; | |
363 | u64 addr; | |
364 | u64 len; | |
365 | }; | |
366 | ||
3fbb51c1 JA |
367 | struct io_connect { |
368 | struct file *file; | |
369 | struct sockaddr __user *addr; | |
370 | int addr_len; | |
371 | }; | |
372 | ||
e47293fd JA |
373 | struct io_sr_msg { |
374 | struct file *file; | |
375 | struct user_msghdr __user *msg; | |
376 | int msg_flags; | |
377 | }; | |
378 | ||
15b71abe JA |
379 | struct io_open { |
380 | struct file *file; | |
381 | int dfd; | |
eddc7ef5 JA |
382 | union { |
383 | umode_t mode; | |
384 | unsigned mask; | |
385 | }; | |
15b71abe JA |
386 | const char __user *fname; |
387 | struct filename *filename; | |
eddc7ef5 | 388 | struct statx __user *buffer; |
15b71abe JA |
389 | int flags; |
390 | }; | |
391 | ||
05f3fb3c JA |
392 | struct io_files_update { |
393 | struct file *file; | |
394 | u64 arg; | |
395 | u32 nr_args; | |
396 | u32 offset; | |
397 | }; | |
398 | ||
f499a021 JA |
399 | struct io_async_connect { |
400 | struct sockaddr_storage address; | |
401 | }; | |
402 | ||
03b1230c JA |
403 | struct io_async_msghdr { |
404 | struct iovec fast_iov[UIO_FASTIOV]; | |
405 | struct iovec *iov; | |
406 | struct sockaddr __user *uaddr; | |
407 | struct msghdr msg; | |
408 | }; | |
409 | ||
f67676d1 JA |
410 | struct io_async_rw { |
411 | struct iovec fast_iov[UIO_FASTIOV]; | |
412 | struct iovec *iov; | |
413 | ssize_t nr_segs; | |
414 | ssize_t size; | |
415 | }; | |
416 | ||
15b71abe JA |
417 | struct io_async_open { |
418 | struct filename *filename; | |
419 | }; | |
420 | ||
1a6b74fc | 421 | struct io_async_ctx { |
f67676d1 JA |
422 | union { |
423 | struct io_async_rw rw; | |
03b1230c | 424 | struct io_async_msghdr msg; |
f499a021 | 425 | struct io_async_connect connect; |
2d28390a | 426 | struct io_timeout_data timeout; |
15b71abe | 427 | struct io_async_open open; |
f67676d1 | 428 | }; |
1a6b74fc JA |
429 | }; |
430 | ||
09bb8394 JA |
431 | /* |
432 | * NOTE! Each of the iocb union members has the file pointer | |
433 | * as the first entry in their struct definition. So you can | |
434 | * access the file pointer through any of the sub-structs, | |
435 | * or directly as just 'ki_filp' in this struct. | |
436 | */ | |
2b188cc1 | 437 | struct io_kiocb { |
221c5eb2 | 438 | union { |
09bb8394 | 439 | struct file *file; |
9adbd45d | 440 | struct io_rw rw; |
221c5eb2 | 441 | struct io_poll_iocb poll; |
8ed8d3c3 JA |
442 | struct io_accept accept; |
443 | struct io_sync sync; | |
fbf23849 | 444 | struct io_cancel cancel; |
b29472ee | 445 | struct io_timeout timeout; |
3fbb51c1 | 446 | struct io_connect connect; |
e47293fd | 447 | struct io_sr_msg sr_msg; |
15b71abe | 448 | struct io_open open; |
b5dba59e | 449 | struct io_close close; |
05f3fb3c | 450 | struct io_files_update files_update; |
221c5eb2 | 451 | }; |
2b188cc1 | 452 | |
1a6b74fc | 453 | struct io_async_ctx *io; |
cf6fd4bd PB |
454 | struct file *ring_file; |
455 | int ring_fd; | |
456 | bool has_user; | |
457 | bool in_async; | |
458 | bool needs_fixed_file; | |
d625c6ee | 459 | u8 opcode; |
2b188cc1 JA |
460 | |
461 | struct io_ring_ctx *ctx; | |
eac406c6 JA |
462 | union { |
463 | struct list_head list; | |
78076bb6 | 464 | struct hlist_node hash_node; |
eac406c6 | 465 | }; |
9e645e11 | 466 | struct list_head link_list; |
2b188cc1 | 467 | unsigned int flags; |
c16361c1 | 468 | refcount_t refs; |
8449eeda | 469 | #define REQ_F_NOWAIT 1 /* must not punt to workers */ |
def596e9 | 470 | #define REQ_F_IOPOLL_COMPLETED 2 /* polled IO has completed */ |
6b06314c | 471 | #define REQ_F_FIXED_FILE 4 /* ctx owns file */ |
4d7dd462 | 472 | #define REQ_F_LINK_NEXT 8 /* already grabbed next link */ |
e2033e33 SB |
473 | #define REQ_F_IO_DRAIN 16 /* drain existing IO first */ |
474 | #define REQ_F_IO_DRAINED 32 /* drain done */ | |
9e645e11 | 475 | #define REQ_F_LINK 64 /* linked sqes */ |
2665abfd | 476 | #define REQ_F_LINK_TIMEOUT 128 /* has linked timeout */ |
f7b76ac9 | 477 | #define REQ_F_FAIL_LINK 256 /* fail rest of links */ |
1b4a51b6 | 478 | #define REQ_F_DRAIN_LINK 512 /* link should be fully drained */ |
5262f567 | 479 | #define REQ_F_TIMEOUT 1024 /* timeout request */ |
491381ce JA |
480 | #define REQ_F_ISREG 2048 /* regular file */ |
481 | #define REQ_F_MUST_PUNT 4096 /* must be punted even for NONBLOCK */ | |
93bd25bb | 482 | #define REQ_F_TIMEOUT_NOSEQ 8192 /* no timeout sequence */ |
fb4b3d3f LT |
483 | #define REQ_F_INFLIGHT 16384 /* on inflight list */ |
484 | #define REQ_F_COMP_LOCKED 32768 /* completion under lock */ | |
4e88d6e7 | 485 | #define REQ_F_HARDLINK 65536 /* doesn't sever on completion < 0 */ |
ce35a47a | 486 | #define REQ_F_FORCE_ASYNC 131072 /* IOSQE_ASYNC */ |
2b188cc1 | 487 | u64 user_data; |
9e645e11 | 488 | u32 result; |
de0617e4 | 489 | u32 sequence; |
2b188cc1 | 490 | |
fcb323cc JA |
491 | struct list_head inflight_entry; |
492 | ||
561fb04a | 493 | struct io_wq_work work; |
2b188cc1 JA |
494 | }; |
495 | ||
496 | #define IO_PLUG_THRESHOLD 2 | |
def596e9 | 497 | #define IO_IOPOLL_BATCH 8 |
2b188cc1 | 498 | |
9a56a232 JA |
499 | struct io_submit_state { |
500 | struct blk_plug plug; | |
501 | ||
2579f913 JA |
502 | /* |
503 | * io_kiocb alloc cache | |
504 | */ | |
505 | void *reqs[IO_IOPOLL_BATCH]; | |
506 | unsigned int free_reqs; | |
507 | unsigned int cur_req; | |
508 | ||
9a56a232 JA |
509 | /* |
510 | * File reference cache | |
511 | */ | |
512 | struct file *file; | |
513 | unsigned int fd; | |
514 | unsigned int has_refs; | |
515 | unsigned int used_refs; | |
516 | unsigned int ios_left; | |
517 | }; | |
518 | ||
561fb04a | 519 | static void io_wq_submit_work(struct io_wq_work **workptr); |
78e19bbe | 520 | static void io_cqring_fill_event(struct io_kiocb *req, long res); |
ec9c02ad | 521 | static void io_put_req(struct io_kiocb *req); |
978db57e | 522 | static void __io_double_put_req(struct io_kiocb *req); |
94ae5e77 JA |
523 | static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req); |
524 | static void io_queue_linked_timeout(struct io_kiocb *req); | |
05f3fb3c JA |
525 | static int __io_sqe_files_update(struct io_ring_ctx *ctx, |
526 | struct io_uring_files_update *ip, | |
527 | unsigned nr_args); | |
de0617e4 | 528 | |
2b188cc1 JA |
529 | static struct kmem_cache *req_cachep; |
530 | ||
531 | static const struct file_operations io_uring_fops; | |
532 | ||
533 | struct sock *io_uring_get_socket(struct file *file) | |
534 | { | |
535 | #if defined(CONFIG_UNIX) | |
536 | if (file->f_op == &io_uring_fops) { | |
537 | struct io_ring_ctx *ctx = file->private_data; | |
538 | ||
539 | return ctx->ring_sock->sk; | |
540 | } | |
541 | #endif | |
542 | return NULL; | |
543 | } | |
544 | EXPORT_SYMBOL(io_uring_get_socket); | |
545 | ||
546 | static void io_ring_ctx_ref_free(struct percpu_ref *ref) | |
547 | { | |
548 | struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs); | |
549 | ||
206aefde | 550 | complete(&ctx->completions[0]); |
2b188cc1 JA |
551 | } |
552 | ||
553 | static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) | |
554 | { | |
555 | struct io_ring_ctx *ctx; | |
78076bb6 | 556 | int hash_bits; |
2b188cc1 JA |
557 | |
558 | ctx = kzalloc(sizeof(*ctx), GFP_KERNEL); | |
559 | if (!ctx) | |
560 | return NULL; | |
561 | ||
0ddf92e8 JA |
562 | ctx->fallback_req = kmem_cache_alloc(req_cachep, GFP_KERNEL); |
563 | if (!ctx->fallback_req) | |
564 | goto err; | |
565 | ||
206aefde JA |
566 | ctx->completions = kmalloc(2 * sizeof(struct completion), GFP_KERNEL); |
567 | if (!ctx->completions) | |
568 | goto err; | |
569 | ||
78076bb6 JA |
570 | /* |
571 | * Use 5 bits less than the max cq entries, that should give us around | |
572 | * 32 entries per hash list if totally full and uniformly spread. | |
573 | */ | |
574 | hash_bits = ilog2(p->cq_entries); | |
575 | hash_bits -= 5; | |
576 | if (hash_bits <= 0) | |
577 | hash_bits = 1; | |
578 | ctx->cancel_hash_bits = hash_bits; | |
579 | ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head), | |
580 | GFP_KERNEL); | |
581 | if (!ctx->cancel_hash) | |
582 | goto err; | |
583 | __hash_init(ctx->cancel_hash, 1U << hash_bits); | |
584 | ||
21482896 | 585 | if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free, |
206aefde JA |
586 | PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) |
587 | goto err; | |
2b188cc1 JA |
588 | |
589 | ctx->flags = p->flags; | |
590 | init_waitqueue_head(&ctx->cq_wait); | |
1d7bb1d5 | 591 | INIT_LIST_HEAD(&ctx->cq_overflow_list); |
206aefde JA |
592 | init_completion(&ctx->completions[0]); |
593 | init_completion(&ctx->completions[1]); | |
2b188cc1 JA |
594 | mutex_init(&ctx->uring_lock); |
595 | init_waitqueue_head(&ctx->wait); | |
596 | spin_lock_init(&ctx->completion_lock); | |
def596e9 | 597 | INIT_LIST_HEAD(&ctx->poll_list); |
de0617e4 | 598 | INIT_LIST_HEAD(&ctx->defer_list); |
5262f567 | 599 | INIT_LIST_HEAD(&ctx->timeout_list); |
fcb323cc JA |
600 | init_waitqueue_head(&ctx->inflight_wait); |
601 | spin_lock_init(&ctx->inflight_lock); | |
602 | INIT_LIST_HEAD(&ctx->inflight_list); | |
2b188cc1 | 603 | return ctx; |
206aefde | 604 | err: |
0ddf92e8 JA |
605 | if (ctx->fallback_req) |
606 | kmem_cache_free(req_cachep, ctx->fallback_req); | |
206aefde | 607 | kfree(ctx->completions); |
78076bb6 | 608 | kfree(ctx->cancel_hash); |
206aefde JA |
609 | kfree(ctx); |
610 | return NULL; | |
2b188cc1 JA |
611 | } |
612 | ||
9d858b21 | 613 | static inline bool __req_need_defer(struct io_kiocb *req) |
7adf4eaf | 614 | { |
a197f664 JL |
615 | struct io_ring_ctx *ctx = req->ctx; |
616 | ||
498ccd9e JA |
617 | return req->sequence != ctx->cached_cq_tail + ctx->cached_sq_dropped |
618 | + atomic_read(&ctx->cached_cq_overflow); | |
7adf4eaf JA |
619 | } |
620 | ||
9d858b21 | 621 | static inline bool req_need_defer(struct io_kiocb *req) |
de0617e4 | 622 | { |
9d858b21 BL |
623 | if ((req->flags & (REQ_F_IO_DRAIN|REQ_F_IO_DRAINED)) == REQ_F_IO_DRAIN) |
624 | return __req_need_defer(req); | |
de0617e4 | 625 | |
9d858b21 | 626 | return false; |
de0617e4 JA |
627 | } |
628 | ||
7adf4eaf | 629 | static struct io_kiocb *io_get_deferred_req(struct io_ring_ctx *ctx) |
de0617e4 JA |
630 | { |
631 | struct io_kiocb *req; | |
632 | ||
7adf4eaf | 633 | req = list_first_entry_or_null(&ctx->defer_list, struct io_kiocb, list); |
9d858b21 | 634 | if (req && !req_need_defer(req)) { |
de0617e4 JA |
635 | list_del_init(&req->list); |
636 | return req; | |
637 | } | |
638 | ||
639 | return NULL; | |
640 | } | |
641 | ||
5262f567 JA |
642 | static struct io_kiocb *io_get_timeout_req(struct io_ring_ctx *ctx) |
643 | { | |
7adf4eaf JA |
644 | struct io_kiocb *req; |
645 | ||
646 | req = list_first_entry_or_null(&ctx->timeout_list, struct io_kiocb, list); | |
93bd25bb JA |
647 | if (req) { |
648 | if (req->flags & REQ_F_TIMEOUT_NOSEQ) | |
649 | return NULL; | |
fb4b3d3f | 650 | if (!__req_need_defer(req)) { |
93bd25bb JA |
651 | list_del_init(&req->list); |
652 | return req; | |
653 | } | |
7adf4eaf JA |
654 | } |
655 | ||
656 | return NULL; | |
5262f567 JA |
657 | } |
658 | ||
de0617e4 | 659 | static void __io_commit_cqring(struct io_ring_ctx *ctx) |
2b188cc1 | 660 | { |
75b28aff | 661 | struct io_rings *rings = ctx->rings; |
2b188cc1 | 662 | |
75b28aff | 663 | if (ctx->cached_cq_tail != READ_ONCE(rings->cq.tail)) { |
2b188cc1 | 664 | /* order cqe stores with ring update */ |
75b28aff | 665 | smp_store_release(&rings->cq.tail, ctx->cached_cq_tail); |
2b188cc1 | 666 | |
2b188cc1 JA |
667 | if (wq_has_sleeper(&ctx->cq_wait)) { |
668 | wake_up_interruptible(&ctx->cq_wait); | |
669 | kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN); | |
670 | } | |
671 | } | |
672 | } | |
673 | ||
d625c6ee | 674 | static inline bool io_req_needs_user(struct io_kiocb *req) |
18d9be1a | 675 | { |
d625c6ee JA |
676 | return !(req->opcode == IORING_OP_READ_FIXED || |
677 | req->opcode == IORING_OP_WRITE_FIXED); | |
561fb04a JA |
678 | } |
679 | ||
94ae5e77 JA |
680 | static inline bool io_prep_async_work(struct io_kiocb *req, |
681 | struct io_kiocb **link) | |
18d9be1a | 682 | { |
561fb04a | 683 | bool do_hashed = false; |
54a91f3b | 684 | |
3529d8c2 JA |
685 | switch (req->opcode) { |
686 | case IORING_OP_WRITEV: | |
687 | case IORING_OP_WRITE_FIXED: | |
688 | /* only regular files should be hashed for writes */ | |
689 | if (req->flags & REQ_F_ISREG) | |
690 | do_hashed = true; | |
691 | /* fall-through */ | |
692 | case IORING_OP_READV: | |
693 | case IORING_OP_READ_FIXED: | |
694 | case IORING_OP_SENDMSG: | |
695 | case IORING_OP_RECVMSG: | |
696 | case IORING_OP_ACCEPT: | |
697 | case IORING_OP_POLL_ADD: | |
698 | case IORING_OP_CONNECT: | |
699 | /* | |
700 | * We know REQ_F_ISREG is not set on some of these | |
701 | * opcodes, but this enables us to keep the check in | |
702 | * just one place. | |
703 | */ | |
704 | if (!(req->flags & REQ_F_ISREG)) | |
705 | req->work.flags |= IO_WQ_WORK_UNBOUND; | |
706 | break; | |
54a91f3b | 707 | } |
3529d8c2 JA |
708 | if (io_req_needs_user(req)) |
709 | req->work.flags |= IO_WQ_WORK_NEEDS_USER; | |
54a91f3b | 710 | |
94ae5e77 | 711 | *link = io_prep_linked_timeout(req); |
561fb04a JA |
712 | return do_hashed; |
713 | } | |
714 | ||
a197f664 | 715 | static inline void io_queue_async_work(struct io_kiocb *req) |
561fb04a | 716 | { |
a197f664 | 717 | struct io_ring_ctx *ctx = req->ctx; |
94ae5e77 JA |
718 | struct io_kiocb *link; |
719 | bool do_hashed; | |
720 | ||
721 | do_hashed = io_prep_async_work(req, &link); | |
561fb04a JA |
722 | |
723 | trace_io_uring_queue_async_work(ctx, do_hashed, req, &req->work, | |
724 | req->flags); | |
725 | if (!do_hashed) { | |
726 | io_wq_enqueue(ctx->io_wq, &req->work); | |
727 | } else { | |
728 | io_wq_enqueue_hashed(ctx->io_wq, &req->work, | |
729 | file_inode(req->file)); | |
730 | } | |
94ae5e77 JA |
731 | |
732 | if (link) | |
733 | io_queue_linked_timeout(link); | |
18d9be1a JA |
734 | } |
735 | ||
5262f567 JA |
736 | static void io_kill_timeout(struct io_kiocb *req) |
737 | { | |
738 | int ret; | |
739 | ||
2d28390a | 740 | ret = hrtimer_try_to_cancel(&req->io->timeout.timer); |
5262f567 JA |
741 | if (ret != -1) { |
742 | atomic_inc(&req->ctx->cq_timeouts); | |
842f9612 | 743 | list_del_init(&req->list); |
78e19bbe | 744 | io_cqring_fill_event(req, 0); |
ec9c02ad | 745 | io_put_req(req); |
5262f567 JA |
746 | } |
747 | } | |
748 | ||
749 | static void io_kill_timeouts(struct io_ring_ctx *ctx) | |
750 | { | |
751 | struct io_kiocb *req, *tmp; | |
752 | ||
753 | spin_lock_irq(&ctx->completion_lock); | |
754 | list_for_each_entry_safe(req, tmp, &ctx->timeout_list, list) | |
755 | io_kill_timeout(req); | |
756 | spin_unlock_irq(&ctx->completion_lock); | |
757 | } | |
758 | ||
de0617e4 JA |
759 | static void io_commit_cqring(struct io_ring_ctx *ctx) |
760 | { | |
761 | struct io_kiocb *req; | |
762 | ||
5262f567 JA |
763 | while ((req = io_get_timeout_req(ctx)) != NULL) |
764 | io_kill_timeout(req); | |
765 | ||
de0617e4 JA |
766 | __io_commit_cqring(ctx); |
767 | ||
768 | while ((req = io_get_deferred_req(ctx)) != NULL) { | |
769 | req->flags |= REQ_F_IO_DRAINED; | |
a197f664 | 770 | io_queue_async_work(req); |
de0617e4 JA |
771 | } |
772 | } | |
773 | ||
2b188cc1 JA |
774 | static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx) |
775 | { | |
75b28aff | 776 | struct io_rings *rings = ctx->rings; |
2b188cc1 JA |
777 | unsigned tail; |
778 | ||
779 | tail = ctx->cached_cq_tail; | |
115e12e5 SB |
780 | /* |
781 | * writes to the cq entry need to come after reading head; the | |
782 | * control dependency is enough as we're using WRITE_ONCE to | |
783 | * fill the cq entry | |
784 | */ | |
75b28aff | 785 | if (tail - READ_ONCE(rings->cq.head) == rings->cq_ring_entries) |
2b188cc1 JA |
786 | return NULL; |
787 | ||
788 | ctx->cached_cq_tail++; | |
75b28aff | 789 | return &rings->cqes[tail & ctx->cq_mask]; |
2b188cc1 JA |
790 | } |
791 | ||
1d7bb1d5 JA |
792 | static void io_cqring_ev_posted(struct io_ring_ctx *ctx) |
793 | { | |
794 | if (waitqueue_active(&ctx->wait)) | |
795 | wake_up(&ctx->wait); | |
796 | if (waitqueue_active(&ctx->sqo_wait)) | |
797 | wake_up(&ctx->sqo_wait); | |
798 | if (ctx->cq_ev_fd) | |
799 | eventfd_signal(ctx->cq_ev_fd, 1); | |
800 | } | |
801 | ||
c4a2ed72 JA |
802 | /* Returns true if there are no backlogged entries after the flush */ |
803 | static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) | |
1d7bb1d5 JA |
804 | { |
805 | struct io_rings *rings = ctx->rings; | |
806 | struct io_uring_cqe *cqe; | |
807 | struct io_kiocb *req; | |
808 | unsigned long flags; | |
809 | LIST_HEAD(list); | |
810 | ||
811 | if (!force) { | |
812 | if (list_empty_careful(&ctx->cq_overflow_list)) | |
c4a2ed72 | 813 | return true; |
1d7bb1d5 JA |
814 | if ((ctx->cached_cq_tail - READ_ONCE(rings->cq.head) == |
815 | rings->cq_ring_entries)) | |
c4a2ed72 | 816 | return false; |
1d7bb1d5 JA |
817 | } |
818 | ||
819 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
820 | ||
821 | /* if force is set, the ring is going away. always drop after that */ | |
822 | if (force) | |
823 | ctx->cq_overflow_flushed = true; | |
824 | ||
c4a2ed72 | 825 | cqe = NULL; |
1d7bb1d5 JA |
826 | while (!list_empty(&ctx->cq_overflow_list)) { |
827 | cqe = io_get_cqring(ctx); | |
828 | if (!cqe && !force) | |
829 | break; | |
830 | ||
831 | req = list_first_entry(&ctx->cq_overflow_list, struct io_kiocb, | |
832 | list); | |
833 | list_move(&req->list, &list); | |
834 | if (cqe) { | |
835 | WRITE_ONCE(cqe->user_data, req->user_data); | |
836 | WRITE_ONCE(cqe->res, req->result); | |
837 | WRITE_ONCE(cqe->flags, 0); | |
838 | } else { | |
839 | WRITE_ONCE(ctx->rings->cq_overflow, | |
840 | atomic_inc_return(&ctx->cached_cq_overflow)); | |
841 | } | |
842 | } | |
843 | ||
844 | io_commit_cqring(ctx); | |
845 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
846 | io_cqring_ev_posted(ctx); | |
847 | ||
848 | while (!list_empty(&list)) { | |
849 | req = list_first_entry(&list, struct io_kiocb, list); | |
850 | list_del(&req->list); | |
ec9c02ad | 851 | io_put_req(req); |
1d7bb1d5 | 852 | } |
c4a2ed72 JA |
853 | |
854 | return cqe != NULL; | |
1d7bb1d5 JA |
855 | } |
856 | ||
78e19bbe | 857 | static void io_cqring_fill_event(struct io_kiocb *req, long res) |
2b188cc1 | 858 | { |
78e19bbe | 859 | struct io_ring_ctx *ctx = req->ctx; |
2b188cc1 JA |
860 | struct io_uring_cqe *cqe; |
861 | ||
78e19bbe | 862 | trace_io_uring_complete(ctx, req->user_data, res); |
51c3ff62 | 863 | |
2b188cc1 JA |
864 | /* |
865 | * If we can't get a cq entry, userspace overflowed the | |
866 | * submission (by quite a lot). Increment the overflow count in | |
867 | * the ring. | |
868 | */ | |
869 | cqe = io_get_cqring(ctx); | |
1d7bb1d5 | 870 | if (likely(cqe)) { |
78e19bbe | 871 | WRITE_ONCE(cqe->user_data, req->user_data); |
2b188cc1 | 872 | WRITE_ONCE(cqe->res, res); |
c71ffb67 | 873 | WRITE_ONCE(cqe->flags, 0); |
1d7bb1d5 | 874 | } else if (ctx->cq_overflow_flushed) { |
498ccd9e JA |
875 | WRITE_ONCE(ctx->rings->cq_overflow, |
876 | atomic_inc_return(&ctx->cached_cq_overflow)); | |
1d7bb1d5 JA |
877 | } else { |
878 | refcount_inc(&req->refs); | |
879 | req->result = res; | |
880 | list_add_tail(&req->list, &ctx->cq_overflow_list); | |
2b188cc1 JA |
881 | } |
882 | } | |
883 | ||
78e19bbe | 884 | static void io_cqring_add_event(struct io_kiocb *req, long res) |
2b188cc1 | 885 | { |
78e19bbe | 886 | struct io_ring_ctx *ctx = req->ctx; |
2b188cc1 JA |
887 | unsigned long flags; |
888 | ||
889 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
78e19bbe | 890 | io_cqring_fill_event(req, res); |
2b188cc1 JA |
891 | io_commit_cqring(ctx); |
892 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
893 | ||
8c838788 | 894 | io_cqring_ev_posted(ctx); |
2b188cc1 JA |
895 | } |
896 | ||
0ddf92e8 JA |
897 | static inline bool io_is_fallback_req(struct io_kiocb *req) |
898 | { | |
899 | return req == (struct io_kiocb *) | |
900 | ((unsigned long) req->ctx->fallback_req & ~1UL); | |
901 | } | |
902 | ||
903 | static struct io_kiocb *io_get_fallback_req(struct io_ring_ctx *ctx) | |
904 | { | |
905 | struct io_kiocb *req; | |
906 | ||
907 | req = ctx->fallback_req; | |
908 | if (!test_and_set_bit_lock(0, (unsigned long *) ctx->fallback_req)) | |
909 | return req; | |
910 | ||
911 | return NULL; | |
912 | } | |
913 | ||
2579f913 JA |
914 | static struct io_kiocb *io_get_req(struct io_ring_ctx *ctx, |
915 | struct io_submit_state *state) | |
2b188cc1 | 916 | { |
fd6fab2c | 917 | gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; |
2b188cc1 JA |
918 | struct io_kiocb *req; |
919 | ||
920 | if (!percpu_ref_tryget(&ctx->refs)) | |
921 | return NULL; | |
922 | ||
2579f913 | 923 | if (!state) { |
fd6fab2c | 924 | req = kmem_cache_alloc(req_cachep, gfp); |
2579f913 | 925 | if (unlikely(!req)) |
0ddf92e8 | 926 | goto fallback; |
2579f913 JA |
927 | } else if (!state->free_reqs) { |
928 | size_t sz; | |
929 | int ret; | |
930 | ||
931 | sz = min_t(size_t, state->ios_left, ARRAY_SIZE(state->reqs)); | |
fd6fab2c JA |
932 | ret = kmem_cache_alloc_bulk(req_cachep, gfp, sz, state->reqs); |
933 | ||
934 | /* | |
935 | * Bulk alloc is all-or-nothing. If we fail to get a batch, | |
936 | * retry single alloc to be on the safe side. | |
937 | */ | |
938 | if (unlikely(ret <= 0)) { | |
939 | state->reqs[0] = kmem_cache_alloc(req_cachep, gfp); | |
940 | if (!state->reqs[0]) | |
0ddf92e8 | 941 | goto fallback; |
fd6fab2c JA |
942 | ret = 1; |
943 | } | |
2579f913 JA |
944 | state->free_reqs = ret - 1; |
945 | state->cur_req = 1; | |
946 | req = state->reqs[0]; | |
947 | } else { | |
948 | req = state->reqs[state->cur_req]; | |
949 | state->free_reqs--; | |
950 | state->cur_req++; | |
2b188cc1 JA |
951 | } |
952 | ||
0ddf92e8 | 953 | got_it: |
1a6b74fc | 954 | req->io = NULL; |
cf6fd4bd | 955 | req->ring_file = NULL; |
60c112b0 | 956 | req->file = NULL; |
2579f913 JA |
957 | req->ctx = ctx; |
958 | req->flags = 0; | |
e65ef56d JA |
959 | /* one is dropped after submission, the other at completion */ |
960 | refcount_set(&req->refs, 2); | |
9e645e11 | 961 | req->result = 0; |
561fb04a | 962 | INIT_IO_WORK(&req->work, io_wq_submit_work); |
2579f913 | 963 | return req; |
0ddf92e8 JA |
964 | fallback: |
965 | req = io_get_fallback_req(ctx); | |
966 | if (req) | |
967 | goto got_it; | |
6805b32e | 968 | percpu_ref_put(&ctx->refs); |
2b188cc1 JA |
969 | return NULL; |
970 | } | |
971 | ||
def596e9 JA |
972 | static void io_free_req_many(struct io_ring_ctx *ctx, void **reqs, int *nr) |
973 | { | |
974 | if (*nr) { | |
975 | kmem_cache_free_bulk(req_cachep, *nr, reqs); | |
6805b32e | 976 | percpu_ref_put_many(&ctx->refs, *nr); |
05f3fb3c | 977 | percpu_ref_put_many(&ctx->file_data->refs, *nr); |
def596e9 JA |
978 | *nr = 0; |
979 | } | |
980 | } | |
981 | ||
9e645e11 | 982 | static void __io_free_req(struct io_kiocb *req) |
2b188cc1 | 983 | { |
fcb323cc JA |
984 | struct io_ring_ctx *ctx = req->ctx; |
985 | ||
1a6b74fc JA |
986 | if (req->io) |
987 | kfree(req->io); | |
05f3fb3c JA |
988 | if (req->file) { |
989 | if (req->flags & REQ_F_FIXED_FILE) | |
990 | percpu_ref_put(&ctx->file_data->refs); | |
991 | else | |
992 | fput(req->file); | |
993 | } | |
fcb323cc JA |
994 | if (req->flags & REQ_F_INFLIGHT) { |
995 | unsigned long flags; | |
996 | ||
997 | spin_lock_irqsave(&ctx->inflight_lock, flags); | |
998 | list_del(&req->inflight_entry); | |
999 | if (waitqueue_active(&ctx->inflight_wait)) | |
1000 | wake_up(&ctx->inflight_wait); | |
1001 | spin_unlock_irqrestore(&ctx->inflight_lock, flags); | |
1002 | } | |
1003 | percpu_ref_put(&ctx->refs); | |
0ddf92e8 JA |
1004 | if (likely(!io_is_fallback_req(req))) |
1005 | kmem_cache_free(req_cachep, req); | |
1006 | else | |
1007 | clear_bit_unlock(0, (unsigned long *) ctx->fallback_req); | |
e65ef56d JA |
1008 | } |
1009 | ||
a197f664 | 1010 | static bool io_link_cancel_timeout(struct io_kiocb *req) |
2665abfd | 1011 | { |
a197f664 | 1012 | struct io_ring_ctx *ctx = req->ctx; |
2665abfd JA |
1013 | int ret; |
1014 | ||
2d28390a | 1015 | ret = hrtimer_try_to_cancel(&req->io->timeout.timer); |
2665abfd | 1016 | if (ret != -1) { |
78e19bbe | 1017 | io_cqring_fill_event(req, -ECANCELED); |
2665abfd JA |
1018 | io_commit_cqring(ctx); |
1019 | req->flags &= ~REQ_F_LINK; | |
ec9c02ad | 1020 | io_put_req(req); |
2665abfd JA |
1021 | return true; |
1022 | } | |
1023 | ||
1024 | return false; | |
e65ef56d JA |
1025 | } |
1026 | ||
ba816ad6 | 1027 | static void io_req_link_next(struct io_kiocb *req, struct io_kiocb **nxtptr) |
9e645e11 | 1028 | { |
2665abfd | 1029 | struct io_ring_ctx *ctx = req->ctx; |
2665abfd | 1030 | bool wake_ev = false; |
9e645e11 | 1031 | |
4d7dd462 JA |
1032 | /* Already got next link */ |
1033 | if (req->flags & REQ_F_LINK_NEXT) | |
1034 | return; | |
1035 | ||
9e645e11 JA |
1036 | /* |
1037 | * The list should never be empty when we are called here. But could | |
1038 | * potentially happen if the chain is messed up, check to be on the | |
1039 | * safe side. | |
1040 | */ | |
4493233e PB |
1041 | while (!list_empty(&req->link_list)) { |
1042 | struct io_kiocb *nxt = list_first_entry(&req->link_list, | |
1043 | struct io_kiocb, link_list); | |
94ae5e77 | 1044 | |
4493233e PB |
1045 | if (unlikely((req->flags & REQ_F_LINK_TIMEOUT) && |
1046 | (nxt->flags & REQ_F_TIMEOUT))) { | |
1047 | list_del_init(&nxt->link_list); | |
94ae5e77 | 1048 | wake_ev |= io_link_cancel_timeout(nxt); |
94ae5e77 JA |
1049 | req->flags &= ~REQ_F_LINK_TIMEOUT; |
1050 | continue; | |
1051 | } | |
9e645e11 | 1052 | |
4493233e PB |
1053 | list_del_init(&req->link_list); |
1054 | if (!list_empty(&nxt->link_list)) | |
1055 | nxt->flags |= REQ_F_LINK; | |
b18fdf71 | 1056 | *nxtptr = nxt; |
94ae5e77 | 1057 | break; |
9e645e11 | 1058 | } |
2665abfd | 1059 | |
4d7dd462 | 1060 | req->flags |= REQ_F_LINK_NEXT; |
2665abfd JA |
1061 | if (wake_ev) |
1062 | io_cqring_ev_posted(ctx); | |
9e645e11 JA |
1063 | } |
1064 | ||
1065 | /* | |
1066 | * Called if REQ_F_LINK is set, and we fail the head request | |
1067 | */ | |
1068 | static void io_fail_links(struct io_kiocb *req) | |
1069 | { | |
2665abfd | 1070 | struct io_ring_ctx *ctx = req->ctx; |
2665abfd JA |
1071 | unsigned long flags; |
1072 | ||
1073 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
9e645e11 JA |
1074 | |
1075 | while (!list_empty(&req->link_list)) { | |
4493233e PB |
1076 | struct io_kiocb *link = list_first_entry(&req->link_list, |
1077 | struct io_kiocb, link_list); | |
9e645e11 | 1078 | |
4493233e | 1079 | list_del_init(&link->link_list); |
c826bd7a | 1080 | trace_io_uring_fail_link(req, link); |
2665abfd JA |
1081 | |
1082 | if ((req->flags & REQ_F_LINK_TIMEOUT) && | |
d625c6ee | 1083 | link->opcode == IORING_OP_LINK_TIMEOUT) { |
a197f664 | 1084 | io_link_cancel_timeout(link); |
2665abfd | 1085 | } else { |
78e19bbe | 1086 | io_cqring_fill_event(link, -ECANCELED); |
978db57e | 1087 | __io_double_put_req(link); |
2665abfd | 1088 | } |
5d960724 | 1089 | req->flags &= ~REQ_F_LINK_TIMEOUT; |
9e645e11 | 1090 | } |
2665abfd JA |
1091 | |
1092 | io_commit_cqring(ctx); | |
1093 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
1094 | io_cqring_ev_posted(ctx); | |
9e645e11 JA |
1095 | } |
1096 | ||
4d7dd462 | 1097 | static void io_req_find_next(struct io_kiocb *req, struct io_kiocb **nxt) |
9e645e11 | 1098 | { |
4d7dd462 | 1099 | if (likely(!(req->flags & REQ_F_LINK))) |
2665abfd | 1100 | return; |
2665abfd | 1101 | |
9e645e11 JA |
1102 | /* |
1103 | * If LINK is set, we have dependent requests in this chain. If we | |
1104 | * didn't fail this request, queue the first one up, moving any other | |
1105 | * dependencies to the next request. In case of failure, fail the rest | |
1106 | * of the chain. | |
1107 | */ | |
2665abfd JA |
1108 | if (req->flags & REQ_F_FAIL_LINK) { |
1109 | io_fail_links(req); | |
7c9e7f0f JA |
1110 | } else if ((req->flags & (REQ_F_LINK_TIMEOUT | REQ_F_COMP_LOCKED)) == |
1111 | REQ_F_LINK_TIMEOUT) { | |
2665abfd JA |
1112 | struct io_ring_ctx *ctx = req->ctx; |
1113 | unsigned long flags; | |
1114 | ||
1115 | /* | |
1116 | * If this is a timeout link, we could be racing with the | |
1117 | * timeout timer. Grab the completion lock for this case to | |
7c9e7f0f | 1118 | * protect against that. |
2665abfd JA |
1119 | */ |
1120 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
1121 | io_req_link_next(req, nxt); | |
1122 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
1123 | } else { | |
1124 | io_req_link_next(req, nxt); | |
9e645e11 | 1125 | } |
4d7dd462 | 1126 | } |
9e645e11 | 1127 | |
c69f8dbe JL |
1128 | static void io_free_req(struct io_kiocb *req) |
1129 | { | |
944e58bf PB |
1130 | struct io_kiocb *nxt = NULL; |
1131 | ||
1132 | io_req_find_next(req, &nxt); | |
70cf9f32 | 1133 | __io_free_req(req); |
944e58bf PB |
1134 | |
1135 | if (nxt) | |
1136 | io_queue_async_work(nxt); | |
c69f8dbe JL |
1137 | } |
1138 | ||
ba816ad6 JA |
1139 | /* |
1140 | * Drop reference to request, return next in chain (if there is one) if this | |
1141 | * was the last reference to this request. | |
1142 | */ | |
f9bd67f6 | 1143 | __attribute__((nonnull)) |
ec9c02ad | 1144 | static void io_put_req_find_next(struct io_kiocb *req, struct io_kiocb **nxtptr) |
e65ef56d | 1145 | { |
f9bd67f6 | 1146 | io_req_find_next(req, nxtptr); |
4d7dd462 | 1147 | |
e65ef56d | 1148 | if (refcount_dec_and_test(&req->refs)) |
4d7dd462 | 1149 | __io_free_req(req); |
2b188cc1 JA |
1150 | } |
1151 | ||
e65ef56d JA |
1152 | static void io_put_req(struct io_kiocb *req) |
1153 | { | |
1154 | if (refcount_dec_and_test(&req->refs)) | |
1155 | io_free_req(req); | |
2b188cc1 JA |
1156 | } |
1157 | ||
978db57e JA |
1158 | /* |
1159 | * Must only be used if we don't need to care about links, usually from | |
1160 | * within the completion handling itself. | |
1161 | */ | |
1162 | static void __io_double_put_req(struct io_kiocb *req) | |
78e19bbe JA |
1163 | { |
1164 | /* drop both submit and complete references */ | |
1165 | if (refcount_sub_and_test(2, &req->refs)) | |
1166 | __io_free_req(req); | |
1167 | } | |
1168 | ||
978db57e JA |
1169 | static void io_double_put_req(struct io_kiocb *req) |
1170 | { | |
1171 | /* drop both submit and complete references */ | |
1172 | if (refcount_sub_and_test(2, &req->refs)) | |
1173 | io_free_req(req); | |
1174 | } | |
1175 | ||
1d7bb1d5 | 1176 | static unsigned io_cqring_events(struct io_ring_ctx *ctx, bool noflush) |
a3a0e43f | 1177 | { |
84f97dc2 JA |
1178 | struct io_rings *rings = ctx->rings; |
1179 | ||
1d7bb1d5 JA |
1180 | /* |
1181 | * noflush == true is from the waitqueue handler, just ensure we wake | |
1182 | * up the task, and the next invocation will flush the entries. We | |
1183 | * cannot safely to it from here. | |
1184 | */ | |
1185 | if (noflush && !list_empty(&ctx->cq_overflow_list)) | |
1186 | return -1U; | |
1187 | ||
1188 | io_cqring_overflow_flush(ctx, false); | |
1189 | ||
a3a0e43f JA |
1190 | /* See comment at the top of this file */ |
1191 | smp_rmb(); | |
75b28aff | 1192 | return READ_ONCE(rings->cq.tail) - READ_ONCE(rings->cq.head); |
a3a0e43f JA |
1193 | } |
1194 | ||
fb5ccc98 PB |
1195 | static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx) |
1196 | { | |
1197 | struct io_rings *rings = ctx->rings; | |
1198 | ||
1199 | /* make sure SQ entry isn't read before tail */ | |
1200 | return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head; | |
1201 | } | |
1202 | ||
def596e9 JA |
1203 | /* |
1204 | * Find and free completed poll iocbs | |
1205 | */ | |
1206 | static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events, | |
1207 | struct list_head *done) | |
1208 | { | |
1209 | void *reqs[IO_IOPOLL_BATCH]; | |
1210 | struct io_kiocb *req; | |
09bb8394 | 1211 | int to_free; |
def596e9 | 1212 | |
09bb8394 | 1213 | to_free = 0; |
def596e9 JA |
1214 | while (!list_empty(done)) { |
1215 | req = list_first_entry(done, struct io_kiocb, list); | |
1216 | list_del(&req->list); | |
1217 | ||
78e19bbe | 1218 | io_cqring_fill_event(req, req->result); |
def596e9 JA |
1219 | (*nr_events)++; |
1220 | ||
09bb8394 JA |
1221 | if (refcount_dec_and_test(&req->refs)) { |
1222 | /* If we're not using fixed files, we have to pair the | |
1223 | * completion part with the file put. Use regular | |
1224 | * completions for those, only batch free for fixed | |
9e645e11 | 1225 | * file and non-linked commands. |
09bb8394 | 1226 | */ |
1a6b74fc JA |
1227 | if (((req->flags & (REQ_F_FIXED_FILE|REQ_F_LINK)) == |
1228 | REQ_F_FIXED_FILE) && !io_is_fallback_req(req) && | |
1229 | !req->io) { | |
09bb8394 JA |
1230 | reqs[to_free++] = req; |
1231 | if (to_free == ARRAY_SIZE(reqs)) | |
1232 | io_free_req_many(ctx, reqs, &to_free); | |
6b06314c | 1233 | } else { |
09bb8394 | 1234 | io_free_req(req); |
6b06314c | 1235 | } |
9a56a232 | 1236 | } |
def596e9 | 1237 | } |
def596e9 | 1238 | |
09bb8394 | 1239 | io_commit_cqring(ctx); |
def596e9 JA |
1240 | io_free_req_many(ctx, reqs, &to_free); |
1241 | } | |
1242 | ||
1243 | static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, | |
1244 | long min) | |
1245 | { | |
1246 | struct io_kiocb *req, *tmp; | |
1247 | LIST_HEAD(done); | |
1248 | bool spin; | |
1249 | int ret; | |
1250 | ||
1251 | /* | |
1252 | * Only spin for completions if we don't have multiple devices hanging | |
1253 | * off our complete list, and we're under the requested amount. | |
1254 | */ | |
1255 | spin = !ctx->poll_multi_file && *nr_events < min; | |
1256 | ||
1257 | ret = 0; | |
1258 | list_for_each_entry_safe(req, tmp, &ctx->poll_list, list) { | |
9adbd45d | 1259 | struct kiocb *kiocb = &req->rw.kiocb; |
def596e9 JA |
1260 | |
1261 | /* | |
1262 | * Move completed entries to our local list. If we find a | |
1263 | * request that requires polling, break out and complete | |
1264 | * the done list first, if we have entries there. | |
1265 | */ | |
1266 | if (req->flags & REQ_F_IOPOLL_COMPLETED) { | |
1267 | list_move_tail(&req->list, &done); | |
1268 | continue; | |
1269 | } | |
1270 | if (!list_empty(&done)) | |
1271 | break; | |
1272 | ||
1273 | ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin); | |
1274 | if (ret < 0) | |
1275 | break; | |
1276 | ||
1277 | if (ret && spin) | |
1278 | spin = false; | |
1279 | ret = 0; | |
1280 | } | |
1281 | ||
1282 | if (!list_empty(&done)) | |
1283 | io_iopoll_complete(ctx, nr_events, &done); | |
1284 | ||
1285 | return ret; | |
1286 | } | |
1287 | ||
1288 | /* | |
d195a66e | 1289 | * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a |
def596e9 JA |
1290 | * non-spinning poll check - we'll still enter the driver poll loop, but only |
1291 | * as a non-spinning completion check. | |
1292 | */ | |
1293 | static int io_iopoll_getevents(struct io_ring_ctx *ctx, unsigned int *nr_events, | |
1294 | long min) | |
1295 | { | |
08f5439f | 1296 | while (!list_empty(&ctx->poll_list) && !need_resched()) { |
def596e9 JA |
1297 | int ret; |
1298 | ||
1299 | ret = io_do_iopoll(ctx, nr_events, min); | |
1300 | if (ret < 0) | |
1301 | return ret; | |
1302 | if (!min || *nr_events >= min) | |
1303 | return 0; | |
1304 | } | |
1305 | ||
1306 | return 1; | |
1307 | } | |
1308 | ||
1309 | /* | |
1310 | * We can't just wait for polled events to come to us, we have to actively | |
1311 | * find and complete them. | |
1312 | */ | |
1313 | static void io_iopoll_reap_events(struct io_ring_ctx *ctx) | |
1314 | { | |
1315 | if (!(ctx->flags & IORING_SETUP_IOPOLL)) | |
1316 | return; | |
1317 | ||
1318 | mutex_lock(&ctx->uring_lock); | |
1319 | while (!list_empty(&ctx->poll_list)) { | |
1320 | unsigned int nr_events = 0; | |
1321 | ||
1322 | io_iopoll_getevents(ctx, &nr_events, 1); | |
08f5439f JA |
1323 | |
1324 | /* | |
1325 | * Ensure we allow local-to-the-cpu processing to take place, | |
1326 | * in this case we need to ensure that we reap all events. | |
1327 | */ | |
1328 | cond_resched(); | |
def596e9 JA |
1329 | } |
1330 | mutex_unlock(&ctx->uring_lock); | |
1331 | } | |
1332 | ||
2b2ed975 JA |
1333 | static int __io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, |
1334 | long min) | |
def596e9 | 1335 | { |
2b2ed975 | 1336 | int iters = 0, ret = 0; |
500f9fba | 1337 | |
def596e9 JA |
1338 | do { |
1339 | int tmin = 0; | |
1340 | ||
a3a0e43f JA |
1341 | /* |
1342 | * Don't enter poll loop if we already have events pending. | |
1343 | * If we do, we can potentially be spinning for commands that | |
1344 | * already triggered a CQE (eg in error). | |
1345 | */ | |
1d7bb1d5 | 1346 | if (io_cqring_events(ctx, false)) |
a3a0e43f JA |
1347 | break; |
1348 | ||
500f9fba JA |
1349 | /* |
1350 | * If a submit got punted to a workqueue, we can have the | |
1351 | * application entering polling for a command before it gets | |
1352 | * issued. That app will hold the uring_lock for the duration | |
1353 | * of the poll right here, so we need to take a breather every | |
1354 | * now and then to ensure that the issue has a chance to add | |
1355 | * the poll to the issued list. Otherwise we can spin here | |
1356 | * forever, while the workqueue is stuck trying to acquire the | |
1357 | * very same mutex. | |
1358 | */ | |
1359 | if (!(++iters & 7)) { | |
1360 | mutex_unlock(&ctx->uring_lock); | |
1361 | mutex_lock(&ctx->uring_lock); | |
1362 | } | |
1363 | ||
def596e9 JA |
1364 | if (*nr_events < min) |
1365 | tmin = min - *nr_events; | |
1366 | ||
1367 | ret = io_iopoll_getevents(ctx, nr_events, tmin); | |
1368 | if (ret <= 0) | |
1369 | break; | |
1370 | ret = 0; | |
1371 | } while (min && !*nr_events && !need_resched()); | |
1372 | ||
2b2ed975 JA |
1373 | return ret; |
1374 | } | |
1375 | ||
1376 | static int io_iopoll_check(struct io_ring_ctx *ctx, unsigned *nr_events, | |
1377 | long min) | |
1378 | { | |
1379 | int ret; | |
1380 | ||
1381 | /* | |
1382 | * We disallow the app entering submit/complete with polling, but we | |
1383 | * still need to lock the ring to prevent racing with polled issue | |
1384 | * that got punted to a workqueue. | |
1385 | */ | |
1386 | mutex_lock(&ctx->uring_lock); | |
1387 | ret = __io_iopoll_check(ctx, nr_events, min); | |
500f9fba | 1388 | mutex_unlock(&ctx->uring_lock); |
def596e9 JA |
1389 | return ret; |
1390 | } | |
1391 | ||
491381ce | 1392 | static void kiocb_end_write(struct io_kiocb *req) |
2b188cc1 | 1393 | { |
491381ce JA |
1394 | /* |
1395 | * Tell lockdep we inherited freeze protection from submission | |
1396 | * thread. | |
1397 | */ | |
1398 | if (req->flags & REQ_F_ISREG) { | |
1399 | struct inode *inode = file_inode(req->file); | |
2b188cc1 | 1400 | |
491381ce | 1401 | __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE); |
2b188cc1 | 1402 | } |
491381ce | 1403 | file_end_write(req->file); |
2b188cc1 JA |
1404 | } |
1405 | ||
4e88d6e7 JA |
1406 | static inline void req_set_fail_links(struct io_kiocb *req) |
1407 | { | |
1408 | if ((req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) == REQ_F_LINK) | |
1409 | req->flags |= REQ_F_FAIL_LINK; | |
1410 | } | |
1411 | ||
ba816ad6 | 1412 | static void io_complete_rw_common(struct kiocb *kiocb, long res) |
2b188cc1 | 1413 | { |
9adbd45d | 1414 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
2b188cc1 | 1415 | |
491381ce JA |
1416 | if (kiocb->ki_flags & IOCB_WRITE) |
1417 | kiocb_end_write(req); | |
2b188cc1 | 1418 | |
4e88d6e7 JA |
1419 | if (res != req->result) |
1420 | req_set_fail_links(req); | |
78e19bbe | 1421 | io_cqring_add_event(req, res); |
ba816ad6 JA |
1422 | } |
1423 | ||
1424 | static void io_complete_rw(struct kiocb *kiocb, long res, long res2) | |
1425 | { | |
9adbd45d | 1426 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
ba816ad6 JA |
1427 | |
1428 | io_complete_rw_common(kiocb, res); | |
e65ef56d | 1429 | io_put_req(req); |
2b188cc1 JA |
1430 | } |
1431 | ||
ba816ad6 JA |
1432 | static struct io_kiocb *__io_complete_rw(struct kiocb *kiocb, long res) |
1433 | { | |
9adbd45d | 1434 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
ec9c02ad | 1435 | struct io_kiocb *nxt = NULL; |
ba816ad6 JA |
1436 | |
1437 | io_complete_rw_common(kiocb, res); | |
ec9c02ad JL |
1438 | io_put_req_find_next(req, &nxt); |
1439 | ||
1440 | return nxt; | |
2b188cc1 JA |
1441 | } |
1442 | ||
def596e9 JA |
1443 | static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2) |
1444 | { | |
9adbd45d | 1445 | struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); |
def596e9 | 1446 | |
491381ce JA |
1447 | if (kiocb->ki_flags & IOCB_WRITE) |
1448 | kiocb_end_write(req); | |
def596e9 | 1449 | |
4e88d6e7 JA |
1450 | if (res != req->result) |
1451 | req_set_fail_links(req); | |
9e645e11 | 1452 | req->result = res; |
def596e9 JA |
1453 | if (res != -EAGAIN) |
1454 | req->flags |= REQ_F_IOPOLL_COMPLETED; | |
1455 | } | |
1456 | ||
1457 | /* | |
1458 | * After the iocb has been issued, it's safe to be found on the poll list. | |
1459 | * Adding the kiocb to the list AFTER submission ensures that we don't | |
1460 | * find it from a io_iopoll_getevents() thread before the issuer is done | |
1461 | * accessing the kiocb cookie. | |
1462 | */ | |
1463 | static void io_iopoll_req_issued(struct io_kiocb *req) | |
1464 | { | |
1465 | struct io_ring_ctx *ctx = req->ctx; | |
1466 | ||
1467 | /* | |
1468 | * Track whether we have multiple files in our lists. This will impact | |
1469 | * how we do polling eventually, not spinning if we're on potentially | |
1470 | * different devices. | |
1471 | */ | |
1472 | if (list_empty(&ctx->poll_list)) { | |
1473 | ctx->poll_multi_file = false; | |
1474 | } else if (!ctx->poll_multi_file) { | |
1475 | struct io_kiocb *list_req; | |
1476 | ||
1477 | list_req = list_first_entry(&ctx->poll_list, struct io_kiocb, | |
1478 | list); | |
9adbd45d | 1479 | if (list_req->file != req->file) |
def596e9 JA |
1480 | ctx->poll_multi_file = true; |
1481 | } | |
1482 | ||
1483 | /* | |
1484 | * For fast devices, IO may have already completed. If it has, add | |
1485 | * it to the front so we find it first. | |
1486 | */ | |
1487 | if (req->flags & REQ_F_IOPOLL_COMPLETED) | |
1488 | list_add(&req->list, &ctx->poll_list); | |
1489 | else | |
1490 | list_add_tail(&req->list, &ctx->poll_list); | |
1491 | } | |
1492 | ||
3d6770fb | 1493 | static void io_file_put(struct io_submit_state *state) |
9a56a232 | 1494 | { |
3d6770fb | 1495 | if (state->file) { |
9a56a232 JA |
1496 | int diff = state->has_refs - state->used_refs; |
1497 | ||
1498 | if (diff) | |
1499 | fput_many(state->file, diff); | |
1500 | state->file = NULL; | |
1501 | } | |
1502 | } | |
1503 | ||
1504 | /* | |
1505 | * Get as many references to a file as we have IOs left in this submission, | |
1506 | * assuming most submissions are for one file, or at least that each file | |
1507 | * has more than one submission. | |
1508 | */ | |
1509 | static struct file *io_file_get(struct io_submit_state *state, int fd) | |
1510 | { | |
1511 | if (!state) | |
1512 | return fget(fd); | |
1513 | ||
1514 | if (state->file) { | |
1515 | if (state->fd == fd) { | |
1516 | state->used_refs++; | |
1517 | state->ios_left--; | |
1518 | return state->file; | |
1519 | } | |
3d6770fb | 1520 | io_file_put(state); |
9a56a232 JA |
1521 | } |
1522 | state->file = fget_many(fd, state->ios_left); | |
1523 | if (!state->file) | |
1524 | return NULL; | |
1525 | ||
1526 | state->fd = fd; | |
1527 | state->has_refs = state->ios_left; | |
1528 | state->used_refs = 1; | |
1529 | state->ios_left--; | |
1530 | return state->file; | |
1531 | } | |
1532 | ||
2b188cc1 JA |
1533 | /* |
1534 | * If we tracked the file through the SCM inflight mechanism, we could support | |
1535 | * any file. For now, just ensure that anything potentially problematic is done | |
1536 | * inline. | |
1537 | */ | |
1538 | static bool io_file_supports_async(struct file *file) | |
1539 | { | |
1540 | umode_t mode = file_inode(file)->i_mode; | |
1541 | ||
10d59345 | 1542 | if (S_ISBLK(mode) || S_ISCHR(mode) || S_ISSOCK(mode)) |
2b188cc1 JA |
1543 | return true; |
1544 | if (S_ISREG(mode) && file->f_op != &io_uring_fops) | |
1545 | return true; | |
1546 | ||
1547 | return false; | |
1548 | } | |
1549 | ||
3529d8c2 JA |
1550 | static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
1551 | bool force_nonblock) | |
2b188cc1 | 1552 | { |
def596e9 | 1553 | struct io_ring_ctx *ctx = req->ctx; |
9adbd45d | 1554 | struct kiocb *kiocb = &req->rw.kiocb; |
09bb8394 JA |
1555 | unsigned ioprio; |
1556 | int ret; | |
2b188cc1 | 1557 | |
09bb8394 JA |
1558 | if (!req->file) |
1559 | return -EBADF; | |
2b188cc1 | 1560 | |
491381ce JA |
1561 | if (S_ISREG(file_inode(req->file)->i_mode)) |
1562 | req->flags |= REQ_F_ISREG; | |
1563 | ||
2b188cc1 JA |
1564 | kiocb->ki_pos = READ_ONCE(sqe->off); |
1565 | kiocb->ki_flags = iocb_flags(kiocb->ki_filp); | |
1566 | kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp)); | |
1567 | ||
1568 | ioprio = READ_ONCE(sqe->ioprio); | |
1569 | if (ioprio) { | |
1570 | ret = ioprio_check_cap(ioprio); | |
1571 | if (ret) | |
09bb8394 | 1572 | return ret; |
2b188cc1 JA |
1573 | |
1574 | kiocb->ki_ioprio = ioprio; | |
1575 | } else | |
1576 | kiocb->ki_ioprio = get_current_ioprio(); | |
1577 | ||
1578 | ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags)); | |
1579 | if (unlikely(ret)) | |
09bb8394 | 1580 | return ret; |
8449eeda SB |
1581 | |
1582 | /* don't allow async punt if RWF_NOWAIT was requested */ | |
491381ce JA |
1583 | if ((kiocb->ki_flags & IOCB_NOWAIT) || |
1584 | (req->file->f_flags & O_NONBLOCK)) | |
8449eeda SB |
1585 | req->flags |= REQ_F_NOWAIT; |
1586 | ||
1587 | if (force_nonblock) | |
2b188cc1 | 1588 | kiocb->ki_flags |= IOCB_NOWAIT; |
8449eeda | 1589 | |
def596e9 | 1590 | if (ctx->flags & IORING_SETUP_IOPOLL) { |
def596e9 JA |
1591 | if (!(kiocb->ki_flags & IOCB_DIRECT) || |
1592 | !kiocb->ki_filp->f_op->iopoll) | |
09bb8394 | 1593 | return -EOPNOTSUPP; |
2b188cc1 | 1594 | |
def596e9 JA |
1595 | kiocb->ki_flags |= IOCB_HIPRI; |
1596 | kiocb->ki_complete = io_complete_rw_iopoll; | |
6873e0bd | 1597 | req->result = 0; |
def596e9 | 1598 | } else { |
09bb8394 JA |
1599 | if (kiocb->ki_flags & IOCB_HIPRI) |
1600 | return -EINVAL; | |
def596e9 JA |
1601 | kiocb->ki_complete = io_complete_rw; |
1602 | } | |
9adbd45d | 1603 | |
3529d8c2 JA |
1604 | req->rw.addr = READ_ONCE(sqe->addr); |
1605 | req->rw.len = READ_ONCE(sqe->len); | |
9adbd45d JA |
1606 | /* we own ->private, reuse it for the buffer index */ |
1607 | req->rw.kiocb.private = (void *) (unsigned long) | |
3529d8c2 | 1608 | READ_ONCE(sqe->buf_index); |
2b188cc1 | 1609 | return 0; |
2b188cc1 JA |
1610 | } |
1611 | ||
1612 | static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret) | |
1613 | { | |
1614 | switch (ret) { | |
1615 | case -EIOCBQUEUED: | |
1616 | break; | |
1617 | case -ERESTARTSYS: | |
1618 | case -ERESTARTNOINTR: | |
1619 | case -ERESTARTNOHAND: | |
1620 | case -ERESTART_RESTARTBLOCK: | |
1621 | /* | |
1622 | * We can't just restart the syscall, since previously | |
1623 | * submitted sqes may already be in progress. Just fail this | |
1624 | * IO with EINTR. | |
1625 | */ | |
1626 | ret = -EINTR; | |
1627 | /* fall through */ | |
1628 | default: | |
1629 | kiocb->ki_complete(kiocb, ret, 0); | |
1630 | } | |
1631 | } | |
1632 | ||
ba816ad6 JA |
1633 | static void kiocb_done(struct kiocb *kiocb, ssize_t ret, struct io_kiocb **nxt, |
1634 | bool in_async) | |
1635 | { | |
f9bd67f6 | 1636 | if (in_async && ret >= 0 && kiocb->ki_complete == io_complete_rw) |
ba816ad6 JA |
1637 | *nxt = __io_complete_rw(kiocb, ret); |
1638 | else | |
1639 | io_rw_done(kiocb, ret); | |
1640 | } | |
1641 | ||
9adbd45d | 1642 | static ssize_t io_import_fixed(struct io_kiocb *req, int rw, |
7d009165 | 1643 | struct iov_iter *iter) |
edafccee | 1644 | { |
9adbd45d JA |
1645 | struct io_ring_ctx *ctx = req->ctx; |
1646 | size_t len = req->rw.len; | |
edafccee JA |
1647 | struct io_mapped_ubuf *imu; |
1648 | unsigned index, buf_index; | |
1649 | size_t offset; | |
1650 | u64 buf_addr; | |
1651 | ||
1652 | /* attempt to use fixed buffers without having provided iovecs */ | |
1653 | if (unlikely(!ctx->user_bufs)) | |
1654 | return -EFAULT; | |
1655 | ||
9adbd45d | 1656 | buf_index = (unsigned long) req->rw.kiocb.private; |
edafccee JA |
1657 | if (unlikely(buf_index >= ctx->nr_user_bufs)) |
1658 | return -EFAULT; | |
1659 | ||
1660 | index = array_index_nospec(buf_index, ctx->nr_user_bufs); | |
1661 | imu = &ctx->user_bufs[index]; | |
9adbd45d | 1662 | buf_addr = req->rw.addr; |
edafccee JA |
1663 | |
1664 | /* overflow */ | |
1665 | if (buf_addr + len < buf_addr) | |
1666 | return -EFAULT; | |
1667 | /* not inside the mapped region */ | |
1668 | if (buf_addr < imu->ubuf || buf_addr + len > imu->ubuf + imu->len) | |
1669 | return -EFAULT; | |
1670 | ||
1671 | /* | |
1672 | * May not be a start of buffer, set size appropriately | |
1673 | * and advance us to the beginning. | |
1674 | */ | |
1675 | offset = buf_addr - imu->ubuf; | |
1676 | iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len); | |
bd11b3a3 JA |
1677 | |
1678 | if (offset) { | |
1679 | /* | |
1680 | * Don't use iov_iter_advance() here, as it's really slow for | |
1681 | * using the latter parts of a big fixed buffer - it iterates | |
1682 | * over each segment manually. We can cheat a bit here, because | |
1683 | * we know that: | |
1684 | * | |
1685 | * 1) it's a BVEC iter, we set it up | |
1686 | * 2) all bvecs are PAGE_SIZE in size, except potentially the | |
1687 | * first and last bvec | |
1688 | * | |
1689 | * So just find our index, and adjust the iterator afterwards. | |
1690 | * If the offset is within the first bvec (or the whole first | |
1691 | * bvec, just use iov_iter_advance(). This makes it easier | |
1692 | * since we can just skip the first segment, which may not | |
1693 | * be PAGE_SIZE aligned. | |
1694 | */ | |
1695 | const struct bio_vec *bvec = imu->bvec; | |
1696 | ||
1697 | if (offset <= bvec->bv_len) { | |
1698 | iov_iter_advance(iter, offset); | |
1699 | } else { | |
1700 | unsigned long seg_skip; | |
1701 | ||
1702 | /* skip first vec */ | |
1703 | offset -= bvec->bv_len; | |
1704 | seg_skip = 1 + (offset >> PAGE_SHIFT); | |
1705 | ||
1706 | iter->bvec = bvec + seg_skip; | |
1707 | iter->nr_segs -= seg_skip; | |
99c79f66 | 1708 | iter->count -= bvec->bv_len + offset; |
bd11b3a3 | 1709 | iter->iov_offset = offset & ~PAGE_MASK; |
bd11b3a3 JA |
1710 | } |
1711 | } | |
1712 | ||
5e559561 | 1713 | return len; |
edafccee JA |
1714 | } |
1715 | ||
cf6fd4bd PB |
1716 | static ssize_t io_import_iovec(int rw, struct io_kiocb *req, |
1717 | struct iovec **iovec, struct iov_iter *iter) | |
2b188cc1 | 1718 | { |
9adbd45d JA |
1719 | void __user *buf = u64_to_user_ptr(req->rw.addr); |
1720 | size_t sqe_len = req->rw.len; | |
edafccee JA |
1721 | u8 opcode; |
1722 | ||
d625c6ee | 1723 | opcode = req->opcode; |
7d009165 | 1724 | if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) { |
edafccee | 1725 | *iovec = NULL; |
9adbd45d | 1726 | return io_import_fixed(req, rw, iter); |
edafccee | 1727 | } |
2b188cc1 | 1728 | |
9adbd45d JA |
1729 | /* buffer index only valid with fixed read/write */ |
1730 | if (req->rw.kiocb.private) | |
1731 | return -EINVAL; | |
1732 | ||
f67676d1 JA |
1733 | if (req->io) { |
1734 | struct io_async_rw *iorw = &req->io->rw; | |
1735 | ||
1736 | *iovec = iorw->iov; | |
1737 | iov_iter_init(iter, rw, *iovec, iorw->nr_segs, iorw->size); | |
1738 | if (iorw->iov == iorw->fast_iov) | |
1739 | *iovec = NULL; | |
1740 | return iorw->size; | |
1741 | } | |
1742 | ||
cf6fd4bd | 1743 | if (!req->has_user) |
2b188cc1 JA |
1744 | return -EFAULT; |
1745 | ||
1746 | #ifdef CONFIG_COMPAT | |
cf6fd4bd | 1747 | if (req->ctx->compat) |
2b188cc1 JA |
1748 | return compat_import_iovec(rw, buf, sqe_len, UIO_FASTIOV, |
1749 | iovec, iter); | |
1750 | #endif | |
1751 | ||
1752 | return import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter); | |
1753 | } | |
1754 | ||
31b51510 | 1755 | /* |
32960613 JA |
1756 | * For files that don't have ->read_iter() and ->write_iter(), handle them |
1757 | * by looping over ->read() or ->write() manually. | |
31b51510 | 1758 | */ |
32960613 JA |
1759 | static ssize_t loop_rw_iter(int rw, struct file *file, struct kiocb *kiocb, |
1760 | struct iov_iter *iter) | |
1761 | { | |
1762 | ssize_t ret = 0; | |
1763 | ||
1764 | /* | |
1765 | * Don't support polled IO through this interface, and we can't | |
1766 | * support non-blocking either. For the latter, this just causes | |
1767 | * the kiocb to be handled from an async context. | |
1768 | */ | |
1769 | if (kiocb->ki_flags & IOCB_HIPRI) | |
1770 | return -EOPNOTSUPP; | |
1771 | if (kiocb->ki_flags & IOCB_NOWAIT) | |
1772 | return -EAGAIN; | |
1773 | ||
1774 | while (iov_iter_count(iter)) { | |
311ae9e1 | 1775 | struct iovec iovec; |
32960613 JA |
1776 | ssize_t nr; |
1777 | ||
311ae9e1 PB |
1778 | if (!iov_iter_is_bvec(iter)) { |
1779 | iovec = iov_iter_iovec(iter); | |
1780 | } else { | |
1781 | /* fixed buffers import bvec */ | |
1782 | iovec.iov_base = kmap(iter->bvec->bv_page) | |
1783 | + iter->iov_offset; | |
1784 | iovec.iov_len = min(iter->count, | |
1785 | iter->bvec->bv_len - iter->iov_offset); | |
1786 | } | |
1787 | ||
32960613 JA |
1788 | if (rw == READ) { |
1789 | nr = file->f_op->read(file, iovec.iov_base, | |
1790 | iovec.iov_len, &kiocb->ki_pos); | |
1791 | } else { | |
1792 | nr = file->f_op->write(file, iovec.iov_base, | |
1793 | iovec.iov_len, &kiocb->ki_pos); | |
1794 | } | |
1795 | ||
311ae9e1 PB |
1796 | if (iov_iter_is_bvec(iter)) |
1797 | kunmap(iter->bvec->bv_page); | |
1798 | ||
32960613 JA |
1799 | if (nr < 0) { |
1800 | if (!ret) | |
1801 | ret = nr; | |
1802 | break; | |
1803 | } | |
1804 | ret += nr; | |
1805 | if (nr != iovec.iov_len) | |
1806 | break; | |
1807 | iov_iter_advance(iter, nr); | |
1808 | } | |
1809 | ||
1810 | return ret; | |
1811 | } | |
1812 | ||
b7bb4f7d | 1813 | static void io_req_map_rw(struct io_kiocb *req, ssize_t io_size, |
f67676d1 JA |
1814 | struct iovec *iovec, struct iovec *fast_iov, |
1815 | struct iov_iter *iter) | |
1816 | { | |
1817 | req->io->rw.nr_segs = iter->nr_segs; | |
1818 | req->io->rw.size = io_size; | |
1819 | req->io->rw.iov = iovec; | |
1820 | if (!req->io->rw.iov) { | |
1821 | req->io->rw.iov = req->io->rw.fast_iov; | |
1822 | memcpy(req->io->rw.iov, fast_iov, | |
1823 | sizeof(struct iovec) * iter->nr_segs); | |
1824 | } | |
1825 | } | |
1826 | ||
b7bb4f7d | 1827 | static int io_alloc_async_ctx(struct io_kiocb *req) |
f67676d1 JA |
1828 | { |
1829 | req->io = kmalloc(sizeof(*req->io), GFP_KERNEL); | |
06b76d44 | 1830 | return req->io == NULL; |
b7bb4f7d JA |
1831 | } |
1832 | ||
1833 | static void io_rw_async(struct io_wq_work **workptr) | |
1834 | { | |
1835 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
1836 | struct iovec *iov = NULL; | |
1837 | ||
1838 | if (req->io->rw.iov != req->io->rw.fast_iov) | |
1839 | iov = req->io->rw.iov; | |
1840 | io_wq_submit_work(workptr); | |
1841 | kfree(iov); | |
1842 | } | |
1843 | ||
1844 | static int io_setup_async_rw(struct io_kiocb *req, ssize_t io_size, | |
1845 | struct iovec *iovec, struct iovec *fast_iov, | |
1846 | struct iov_iter *iter) | |
1847 | { | |
74566df3 JA |
1848 | if (req->opcode == IORING_OP_READ_FIXED || |
1849 | req->opcode == IORING_OP_WRITE_FIXED) | |
1850 | return 0; | |
b7bb4f7d JA |
1851 | if (!req->io && io_alloc_async_ctx(req)) |
1852 | return -ENOMEM; | |
1853 | ||
1854 | io_req_map_rw(req, io_size, iovec, fast_iov, iter); | |
1855 | req->work.func = io_rw_async; | |
1856 | return 0; | |
f67676d1 JA |
1857 | } |
1858 | ||
3529d8c2 JA |
1859 | static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
1860 | bool force_nonblock) | |
f67676d1 | 1861 | { |
3529d8c2 JA |
1862 | struct io_async_ctx *io; |
1863 | struct iov_iter iter; | |
f67676d1 JA |
1864 | ssize_t ret; |
1865 | ||
3529d8c2 JA |
1866 | ret = io_prep_rw(req, sqe, force_nonblock); |
1867 | if (ret) | |
1868 | return ret; | |
f67676d1 | 1869 | |
3529d8c2 JA |
1870 | if (unlikely(!(req->file->f_mode & FMODE_READ))) |
1871 | return -EBADF; | |
f67676d1 | 1872 | |
3529d8c2 JA |
1873 | if (!req->io) |
1874 | return 0; | |
1875 | ||
1876 | io = req->io; | |
1877 | io->rw.iov = io->rw.fast_iov; | |
1878 | req->io = NULL; | |
1879 | ret = io_import_iovec(READ, req, &io->rw.iov, &iter); | |
1880 | req->io = io; | |
1881 | if (ret < 0) | |
1882 | return ret; | |
1883 | ||
1884 | io_req_map_rw(req, ret, io->rw.iov, io->rw.fast_iov, &iter); | |
1885 | return 0; | |
f67676d1 JA |
1886 | } |
1887 | ||
267bc904 | 1888 | static int io_read(struct io_kiocb *req, struct io_kiocb **nxt, |
8358e3a8 | 1889 | bool force_nonblock) |
2b188cc1 JA |
1890 | { |
1891 | struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; | |
9adbd45d | 1892 | struct kiocb *kiocb = &req->rw.kiocb; |
2b188cc1 | 1893 | struct iov_iter iter; |
31b51510 | 1894 | size_t iov_count; |
f67676d1 | 1895 | ssize_t io_size, ret; |
2b188cc1 | 1896 | |
3529d8c2 | 1897 | ret = io_import_iovec(READ, req, &iovec, &iter); |
06b76d44 JA |
1898 | if (ret < 0) |
1899 | return ret; | |
2b188cc1 | 1900 | |
fd6c2e4c JA |
1901 | /* Ensure we clear previously set non-block flag */ |
1902 | if (!force_nonblock) | |
9adbd45d | 1903 | req->rw.kiocb.ki_flags &= ~IOCB_NOWAIT; |
fd6c2e4c | 1904 | |
797f3f53 | 1905 | req->result = 0; |
f67676d1 | 1906 | io_size = ret; |
9e645e11 | 1907 | if (req->flags & REQ_F_LINK) |
f67676d1 JA |
1908 | req->result = io_size; |
1909 | ||
1910 | /* | |
1911 | * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so | |
1912 | * we know to async punt it even if it was opened O_NONBLOCK | |
1913 | */ | |
9adbd45d | 1914 | if (force_nonblock && !io_file_supports_async(req->file)) { |
f67676d1 JA |
1915 | req->flags |= REQ_F_MUST_PUNT; |
1916 | goto copy_iov; | |
1917 | } | |
9e645e11 | 1918 | |
31b51510 | 1919 | iov_count = iov_iter_count(&iter); |
9adbd45d | 1920 | ret = rw_verify_area(READ, req->file, &kiocb->ki_pos, iov_count); |
2b188cc1 JA |
1921 | if (!ret) { |
1922 | ssize_t ret2; | |
1923 | ||
9adbd45d JA |
1924 | if (req->file->f_op->read_iter) |
1925 | ret2 = call_read_iter(req->file, kiocb, &iter); | |
32960613 | 1926 | else |
9adbd45d | 1927 | ret2 = loop_rw_iter(READ, req->file, kiocb, &iter); |
32960613 | 1928 | |
9d93a3f5 | 1929 | /* Catch -EAGAIN return for forced non-blocking submission */ |
f67676d1 | 1930 | if (!force_nonblock || ret2 != -EAGAIN) { |
cf6fd4bd | 1931 | kiocb_done(kiocb, ret2, nxt, req->in_async); |
f67676d1 JA |
1932 | } else { |
1933 | copy_iov: | |
b7bb4f7d | 1934 | ret = io_setup_async_rw(req, io_size, iovec, |
f67676d1 JA |
1935 | inline_vecs, &iter); |
1936 | if (ret) | |
1937 | goto out_free; | |
1938 | return -EAGAIN; | |
1939 | } | |
2b188cc1 | 1940 | } |
f67676d1 | 1941 | out_free: |
b7bb4f7d JA |
1942 | if (!io_wq_current_is_worker()) |
1943 | kfree(iovec); | |
2b188cc1 JA |
1944 | return ret; |
1945 | } | |
1946 | ||
3529d8c2 JA |
1947 | static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
1948 | bool force_nonblock) | |
f67676d1 | 1949 | { |
3529d8c2 JA |
1950 | struct io_async_ctx *io; |
1951 | struct iov_iter iter; | |
f67676d1 JA |
1952 | ssize_t ret; |
1953 | ||
3529d8c2 JA |
1954 | ret = io_prep_rw(req, sqe, force_nonblock); |
1955 | if (ret) | |
1956 | return ret; | |
f67676d1 | 1957 | |
3529d8c2 JA |
1958 | if (unlikely(!(req->file->f_mode & FMODE_WRITE))) |
1959 | return -EBADF; | |
f67676d1 | 1960 | |
3529d8c2 JA |
1961 | if (!req->io) |
1962 | return 0; | |
1963 | ||
1964 | io = req->io; | |
1965 | io->rw.iov = io->rw.fast_iov; | |
1966 | req->io = NULL; | |
1967 | ret = io_import_iovec(WRITE, req, &io->rw.iov, &iter); | |
1968 | req->io = io; | |
1969 | if (ret < 0) | |
1970 | return ret; | |
1971 | ||
1972 | io_req_map_rw(req, ret, io->rw.iov, io->rw.fast_iov, &iter); | |
1973 | return 0; | |
f67676d1 JA |
1974 | } |
1975 | ||
267bc904 | 1976 | static int io_write(struct io_kiocb *req, struct io_kiocb **nxt, |
8358e3a8 | 1977 | bool force_nonblock) |
2b188cc1 JA |
1978 | { |
1979 | struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; | |
9adbd45d | 1980 | struct kiocb *kiocb = &req->rw.kiocb; |
2b188cc1 | 1981 | struct iov_iter iter; |
31b51510 | 1982 | size_t iov_count; |
f67676d1 | 1983 | ssize_t ret, io_size; |
2b188cc1 | 1984 | |
3529d8c2 | 1985 | ret = io_import_iovec(WRITE, req, &iovec, &iter); |
06b76d44 JA |
1986 | if (ret < 0) |
1987 | return ret; | |
2b188cc1 | 1988 | |
fd6c2e4c JA |
1989 | /* Ensure we clear previously set non-block flag */ |
1990 | if (!force_nonblock) | |
9adbd45d | 1991 | req->rw.kiocb.ki_flags &= ~IOCB_NOWAIT; |
fd6c2e4c | 1992 | |
797f3f53 | 1993 | req->result = 0; |
f67676d1 | 1994 | io_size = ret; |
9e645e11 | 1995 | if (req->flags & REQ_F_LINK) |
f67676d1 | 1996 | req->result = io_size; |
9e645e11 | 1997 | |
f67676d1 JA |
1998 | /* |
1999 | * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so | |
2000 | * we know to async punt it even if it was opened O_NONBLOCK | |
2001 | */ | |
2002 | if (force_nonblock && !io_file_supports_async(req->file)) { | |
2003 | req->flags |= REQ_F_MUST_PUNT; | |
2004 | goto copy_iov; | |
2005 | } | |
31b51510 | 2006 | |
10d59345 JA |
2007 | /* file path doesn't support NOWAIT for non-direct_IO */ |
2008 | if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) && | |
2009 | (req->flags & REQ_F_ISREG)) | |
f67676d1 | 2010 | goto copy_iov; |
31b51510 | 2011 | |
f67676d1 | 2012 | iov_count = iov_iter_count(&iter); |
9adbd45d | 2013 | ret = rw_verify_area(WRITE, req->file, &kiocb->ki_pos, iov_count); |
2b188cc1 | 2014 | if (!ret) { |
9bf7933f RP |
2015 | ssize_t ret2; |
2016 | ||
2b188cc1 JA |
2017 | /* |
2018 | * Open-code file_start_write here to grab freeze protection, | |
2019 | * which will be released by another thread in | |
2020 | * io_complete_rw(). Fool lockdep by telling it the lock got | |
2021 | * released so that it doesn't complain about the held lock when | |
2022 | * we return to userspace. | |
2023 | */ | |
491381ce | 2024 | if (req->flags & REQ_F_ISREG) { |
9adbd45d | 2025 | __sb_start_write(file_inode(req->file)->i_sb, |
2b188cc1 | 2026 | SB_FREEZE_WRITE, true); |
9adbd45d | 2027 | __sb_writers_release(file_inode(req->file)->i_sb, |
2b188cc1 JA |
2028 | SB_FREEZE_WRITE); |
2029 | } | |
2030 | kiocb->ki_flags |= IOCB_WRITE; | |
9bf7933f | 2031 | |
9adbd45d JA |
2032 | if (req->file->f_op->write_iter) |
2033 | ret2 = call_write_iter(req->file, kiocb, &iter); | |
32960613 | 2034 | else |
9adbd45d | 2035 | ret2 = loop_rw_iter(WRITE, req->file, kiocb, &iter); |
f67676d1 | 2036 | if (!force_nonblock || ret2 != -EAGAIN) { |
cf6fd4bd | 2037 | kiocb_done(kiocb, ret2, nxt, req->in_async); |
f67676d1 JA |
2038 | } else { |
2039 | copy_iov: | |
b7bb4f7d | 2040 | ret = io_setup_async_rw(req, io_size, iovec, |
f67676d1 JA |
2041 | inline_vecs, &iter); |
2042 | if (ret) | |
2043 | goto out_free; | |
2044 | return -EAGAIN; | |
2045 | } | |
2b188cc1 | 2046 | } |
31b51510 | 2047 | out_free: |
b7bb4f7d JA |
2048 | if (!io_wq_current_is_worker()) |
2049 | kfree(iovec); | |
2b188cc1 JA |
2050 | return ret; |
2051 | } | |
2052 | ||
2053 | /* | |
2054 | * IORING_OP_NOP just posts a completion event, nothing else. | |
2055 | */ | |
78e19bbe | 2056 | static int io_nop(struct io_kiocb *req) |
2b188cc1 JA |
2057 | { |
2058 | struct io_ring_ctx *ctx = req->ctx; | |
2b188cc1 | 2059 | |
def596e9 JA |
2060 | if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) |
2061 | return -EINVAL; | |
2062 | ||
78e19bbe | 2063 | io_cqring_add_event(req, 0); |
e65ef56d | 2064 | io_put_req(req); |
2b188cc1 JA |
2065 | return 0; |
2066 | } | |
2067 | ||
3529d8c2 | 2068 | static int io_prep_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
c992fe29 | 2069 | { |
6b06314c | 2070 | struct io_ring_ctx *ctx = req->ctx; |
c992fe29 | 2071 | |
09bb8394 JA |
2072 | if (!req->file) |
2073 | return -EBADF; | |
c992fe29 | 2074 | |
6b06314c | 2075 | if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) |
def596e9 | 2076 | return -EINVAL; |
edafccee | 2077 | if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index)) |
c992fe29 CH |
2078 | return -EINVAL; |
2079 | ||
8ed8d3c3 JA |
2080 | req->sync.flags = READ_ONCE(sqe->fsync_flags); |
2081 | if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC)) | |
2082 | return -EINVAL; | |
2083 | ||
2084 | req->sync.off = READ_ONCE(sqe->off); | |
2085 | req->sync.len = READ_ONCE(sqe->len); | |
c992fe29 CH |
2086 | return 0; |
2087 | } | |
2088 | ||
8ed8d3c3 JA |
2089 | static bool io_req_cancelled(struct io_kiocb *req) |
2090 | { | |
2091 | if (req->work.flags & IO_WQ_WORK_CANCEL) { | |
2092 | req_set_fail_links(req); | |
2093 | io_cqring_add_event(req, -ECANCELED); | |
2094 | io_put_req(req); | |
2095 | return true; | |
2096 | } | |
2097 | ||
2098 | return false; | |
2099 | } | |
2100 | ||
78912934 JA |
2101 | static void io_link_work_cb(struct io_wq_work **workptr) |
2102 | { | |
2103 | struct io_wq_work *work = *workptr; | |
2104 | struct io_kiocb *link = work->data; | |
2105 | ||
2106 | io_queue_linked_timeout(link); | |
2107 | work->func = io_wq_submit_work; | |
2108 | } | |
2109 | ||
2110 | static void io_wq_assign_next(struct io_wq_work **workptr, struct io_kiocb *nxt) | |
2111 | { | |
2112 | struct io_kiocb *link; | |
2113 | ||
2114 | io_prep_async_work(nxt, &link); | |
2115 | *workptr = &nxt->work; | |
2116 | if (link) { | |
2117 | nxt->work.flags |= IO_WQ_WORK_CB; | |
2118 | nxt->work.func = io_link_work_cb; | |
2119 | nxt->work.data = link; | |
2120 | } | |
2121 | } | |
2122 | ||
8ed8d3c3 JA |
2123 | static void io_fsync_finish(struct io_wq_work **workptr) |
2124 | { | |
2125 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2126 | loff_t end = req->sync.off + req->sync.len; | |
2127 | struct io_kiocb *nxt = NULL; | |
2128 | int ret; | |
2129 | ||
2130 | if (io_req_cancelled(req)) | |
2131 | return; | |
2132 | ||
9adbd45d | 2133 | ret = vfs_fsync_range(req->file, req->sync.off, |
8ed8d3c3 JA |
2134 | end > 0 ? end : LLONG_MAX, |
2135 | req->sync.flags & IORING_FSYNC_DATASYNC); | |
2136 | if (ret < 0) | |
2137 | req_set_fail_links(req); | |
2138 | io_cqring_add_event(req, ret); | |
2139 | io_put_req_find_next(req, &nxt); | |
2140 | if (nxt) | |
78912934 | 2141 | io_wq_assign_next(workptr, nxt); |
8ed8d3c3 JA |
2142 | } |
2143 | ||
fc4df999 JA |
2144 | static int io_fsync(struct io_kiocb *req, struct io_kiocb **nxt, |
2145 | bool force_nonblock) | |
c992fe29 | 2146 | { |
8ed8d3c3 | 2147 | struct io_wq_work *work, *old_work; |
c992fe29 CH |
2148 | |
2149 | /* fsync always requires a blocking context */ | |
8ed8d3c3 JA |
2150 | if (force_nonblock) { |
2151 | io_put_req(req); | |
2152 | req->work.func = io_fsync_finish; | |
c992fe29 | 2153 | return -EAGAIN; |
8ed8d3c3 | 2154 | } |
c992fe29 | 2155 | |
8ed8d3c3 JA |
2156 | work = old_work = &req->work; |
2157 | io_fsync_finish(&work); | |
2158 | if (work && work != old_work) | |
2159 | *nxt = container_of(work, struct io_kiocb, work); | |
c992fe29 CH |
2160 | return 0; |
2161 | } | |
2162 | ||
d63d1b5e JA |
2163 | static void io_fallocate_finish(struct io_wq_work **workptr) |
2164 | { | |
2165 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2166 | struct io_kiocb *nxt = NULL; | |
2167 | int ret; | |
2168 | ||
2169 | ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off, | |
2170 | req->sync.len); | |
2171 | if (ret < 0) | |
2172 | req_set_fail_links(req); | |
2173 | io_cqring_add_event(req, ret); | |
2174 | io_put_req_find_next(req, &nxt); | |
2175 | if (nxt) | |
2176 | io_wq_assign_next(workptr, nxt); | |
2177 | } | |
2178 | ||
2179 | static int io_fallocate_prep(struct io_kiocb *req, | |
2180 | const struct io_uring_sqe *sqe) | |
2181 | { | |
2182 | if (sqe->ioprio || sqe->buf_index || sqe->rw_flags) | |
2183 | return -EINVAL; | |
2184 | ||
2185 | req->sync.off = READ_ONCE(sqe->off); | |
2186 | req->sync.len = READ_ONCE(sqe->addr); | |
2187 | req->sync.mode = READ_ONCE(sqe->len); | |
2188 | return 0; | |
2189 | } | |
2190 | ||
2191 | static int io_fallocate(struct io_kiocb *req, struct io_kiocb **nxt, | |
2192 | bool force_nonblock) | |
2193 | { | |
2194 | struct io_wq_work *work, *old_work; | |
2195 | ||
2196 | /* fallocate always requiring blocking context */ | |
2197 | if (force_nonblock) { | |
2198 | io_put_req(req); | |
2199 | req->work.func = io_fallocate_finish; | |
2200 | return -EAGAIN; | |
2201 | } | |
2202 | ||
2203 | work = old_work = &req->work; | |
2204 | io_fallocate_finish(&work); | |
2205 | if (work && work != old_work) | |
2206 | *nxt = container_of(work, struct io_kiocb, work); | |
2207 | ||
2208 | return 0; | |
2209 | } | |
2210 | ||
15b71abe JA |
2211 | static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2212 | { | |
2213 | int ret; | |
2214 | ||
2215 | if (sqe->ioprio || sqe->buf_index) | |
2216 | return -EINVAL; | |
2217 | ||
2218 | req->open.dfd = READ_ONCE(sqe->fd); | |
2219 | req->open.mode = READ_ONCE(sqe->len); | |
2220 | req->open.fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); | |
2221 | req->open.flags = READ_ONCE(sqe->open_flags); | |
2222 | ||
2223 | req->open.filename = getname(req->open.fname); | |
2224 | if (IS_ERR(req->open.filename)) { | |
2225 | ret = PTR_ERR(req->open.filename); | |
2226 | req->open.filename = NULL; | |
2227 | return ret; | |
2228 | } | |
2229 | ||
2230 | return 0; | |
2231 | } | |
2232 | ||
2233 | static int io_openat(struct io_kiocb *req, struct io_kiocb **nxt, | |
2234 | bool force_nonblock) | |
2235 | { | |
2236 | struct open_flags op; | |
2237 | struct open_how how; | |
2238 | struct file *file; | |
2239 | int ret; | |
2240 | ||
2241 | if (force_nonblock) { | |
2242 | req->work.flags |= IO_WQ_WORK_NEEDS_FILES; | |
2243 | return -EAGAIN; | |
2244 | } | |
2245 | ||
2246 | how = build_open_how(req->open.flags, req->open.mode); | |
2247 | ret = build_open_flags(&how, &op); | |
2248 | if (ret) | |
2249 | goto err; | |
2250 | ||
2251 | ret = get_unused_fd_flags(how.flags); | |
2252 | if (ret < 0) | |
2253 | goto err; | |
2254 | ||
2255 | file = do_filp_open(req->open.dfd, req->open.filename, &op); | |
2256 | if (IS_ERR(file)) { | |
2257 | put_unused_fd(ret); | |
2258 | ret = PTR_ERR(file); | |
2259 | } else { | |
2260 | fsnotify_open(file); | |
2261 | fd_install(ret, file); | |
2262 | } | |
2263 | err: | |
2264 | putname(req->open.filename); | |
2265 | if (ret < 0) | |
2266 | req_set_fail_links(req); | |
2267 | io_cqring_add_event(req, ret); | |
2268 | io_put_req_find_next(req, nxt); | |
2269 | return 0; | |
2270 | } | |
2271 | ||
eddc7ef5 JA |
2272 | static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2273 | { | |
2274 | unsigned lookup_flags; | |
2275 | int ret; | |
2276 | ||
2277 | if (sqe->ioprio || sqe->buf_index) | |
2278 | return -EINVAL; | |
2279 | ||
2280 | req->open.dfd = READ_ONCE(sqe->fd); | |
2281 | req->open.mask = READ_ONCE(sqe->len); | |
2282 | req->open.fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); | |
2283 | req->open.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2)); | |
2284 | req->open.flags = READ_ONCE(sqe->statx_flags); | |
2285 | ||
2286 | if (vfs_stat_set_lookup_flags(&lookup_flags, req->open.flags)) | |
2287 | return -EINVAL; | |
2288 | ||
2289 | req->open.filename = getname_flags(req->open.fname, lookup_flags, NULL); | |
2290 | if (IS_ERR(req->open.filename)) { | |
2291 | ret = PTR_ERR(req->open.filename); | |
2292 | req->open.filename = NULL; | |
2293 | return ret; | |
2294 | } | |
2295 | ||
2296 | return 0; | |
2297 | } | |
2298 | ||
2299 | static int io_statx(struct io_kiocb *req, struct io_kiocb **nxt, | |
2300 | bool force_nonblock) | |
2301 | { | |
2302 | struct io_open *ctx = &req->open; | |
2303 | unsigned lookup_flags; | |
2304 | struct path path; | |
2305 | struct kstat stat; | |
2306 | int ret; | |
2307 | ||
2308 | if (force_nonblock) | |
2309 | return -EAGAIN; | |
2310 | ||
2311 | if (vfs_stat_set_lookup_flags(&lookup_flags, ctx->flags)) | |
2312 | return -EINVAL; | |
2313 | ||
2314 | retry: | |
2315 | /* filename_lookup() drops it, keep a reference */ | |
2316 | ctx->filename->refcnt++; | |
2317 | ||
2318 | ret = filename_lookup(ctx->dfd, ctx->filename, lookup_flags, &path, | |
2319 | NULL); | |
2320 | if (ret) | |
2321 | goto err; | |
2322 | ||
2323 | ret = vfs_getattr(&path, &stat, ctx->mask, ctx->flags); | |
2324 | path_put(&path); | |
2325 | if (retry_estale(ret, lookup_flags)) { | |
2326 | lookup_flags |= LOOKUP_REVAL; | |
2327 | goto retry; | |
2328 | } | |
2329 | if (!ret) | |
2330 | ret = cp_statx(&stat, ctx->buffer); | |
2331 | err: | |
2332 | putname(ctx->filename); | |
2333 | if (ret < 0) | |
2334 | req_set_fail_links(req); | |
2335 | io_cqring_add_event(req, ret); | |
2336 | io_put_req_find_next(req, nxt); | |
2337 | return 0; | |
2338 | } | |
2339 | ||
b5dba59e JA |
2340 | static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2341 | { | |
2342 | /* | |
2343 | * If we queue this for async, it must not be cancellable. That would | |
2344 | * leave the 'file' in an undeterminate state. | |
2345 | */ | |
2346 | req->work.flags |= IO_WQ_WORK_NO_CANCEL; | |
2347 | ||
2348 | if (sqe->ioprio || sqe->off || sqe->addr || sqe->len || | |
2349 | sqe->rw_flags || sqe->buf_index) | |
2350 | return -EINVAL; | |
2351 | if (sqe->flags & IOSQE_FIXED_FILE) | |
2352 | return -EINVAL; | |
2353 | ||
2354 | req->close.fd = READ_ONCE(sqe->fd); | |
2355 | if (req->file->f_op == &io_uring_fops || | |
2356 | req->close.fd == req->ring_fd) | |
2357 | return -EBADF; | |
2358 | ||
2359 | return 0; | |
2360 | } | |
2361 | ||
2362 | static void io_close_finish(struct io_wq_work **workptr) | |
2363 | { | |
2364 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2365 | struct io_kiocb *nxt = NULL; | |
2366 | ||
2367 | /* Invoked with files, we need to do the close */ | |
2368 | if (req->work.files) { | |
2369 | int ret; | |
2370 | ||
2371 | ret = filp_close(req->close.put_file, req->work.files); | |
2372 | if (ret < 0) { | |
2373 | req_set_fail_links(req); | |
2374 | } | |
2375 | io_cqring_add_event(req, ret); | |
2376 | } | |
2377 | ||
2378 | fput(req->close.put_file); | |
2379 | ||
2380 | /* we bypassed the re-issue, drop the submission reference */ | |
2381 | io_put_req(req); | |
2382 | io_put_req_find_next(req, &nxt); | |
2383 | if (nxt) | |
2384 | io_wq_assign_next(workptr, nxt); | |
2385 | } | |
2386 | ||
2387 | static int io_close(struct io_kiocb *req, struct io_kiocb **nxt, | |
2388 | bool force_nonblock) | |
2389 | { | |
2390 | int ret; | |
2391 | ||
2392 | req->close.put_file = NULL; | |
2393 | ret = __close_fd_get_file(req->close.fd, &req->close.put_file); | |
2394 | if (ret < 0) | |
2395 | return ret; | |
2396 | ||
2397 | /* if the file has a flush method, be safe and punt to async */ | |
2398 | if (req->close.put_file->f_op->flush && !io_wq_current_is_worker()) { | |
2399 | req->work.flags |= IO_WQ_WORK_NEEDS_FILES; | |
2400 | goto eagain; | |
2401 | } | |
2402 | ||
2403 | /* | |
2404 | * No ->flush(), safely close from here and just punt the | |
2405 | * fput() to async context. | |
2406 | */ | |
2407 | ret = filp_close(req->close.put_file, current->files); | |
2408 | ||
2409 | if (ret < 0) | |
2410 | req_set_fail_links(req); | |
2411 | io_cqring_add_event(req, ret); | |
2412 | ||
2413 | if (io_wq_current_is_worker()) { | |
2414 | struct io_wq_work *old_work, *work; | |
2415 | ||
2416 | old_work = work = &req->work; | |
2417 | io_close_finish(&work); | |
2418 | if (work && work != old_work) | |
2419 | *nxt = container_of(work, struct io_kiocb, work); | |
2420 | return 0; | |
2421 | } | |
2422 | ||
2423 | eagain: | |
2424 | req->work.func = io_close_finish; | |
2425 | return -EAGAIN; | |
2426 | } | |
2427 | ||
3529d8c2 | 2428 | static int io_prep_sfr(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
5d17b4a4 JA |
2429 | { |
2430 | struct io_ring_ctx *ctx = req->ctx; | |
5d17b4a4 JA |
2431 | |
2432 | if (!req->file) | |
2433 | return -EBADF; | |
5d17b4a4 JA |
2434 | |
2435 | if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) | |
2436 | return -EINVAL; | |
2437 | if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index)) | |
2438 | return -EINVAL; | |
2439 | ||
8ed8d3c3 JA |
2440 | req->sync.off = READ_ONCE(sqe->off); |
2441 | req->sync.len = READ_ONCE(sqe->len); | |
2442 | req->sync.flags = READ_ONCE(sqe->sync_range_flags); | |
8ed8d3c3 JA |
2443 | return 0; |
2444 | } | |
2445 | ||
2446 | static void io_sync_file_range_finish(struct io_wq_work **workptr) | |
2447 | { | |
2448 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2449 | struct io_kiocb *nxt = NULL; | |
2450 | int ret; | |
2451 | ||
2452 | if (io_req_cancelled(req)) | |
2453 | return; | |
2454 | ||
9adbd45d | 2455 | ret = sync_file_range(req->file, req->sync.off, req->sync.len, |
8ed8d3c3 JA |
2456 | req->sync.flags); |
2457 | if (ret < 0) | |
2458 | req_set_fail_links(req); | |
2459 | io_cqring_add_event(req, ret); | |
2460 | io_put_req_find_next(req, &nxt); | |
2461 | if (nxt) | |
78912934 | 2462 | io_wq_assign_next(workptr, nxt); |
5d17b4a4 JA |
2463 | } |
2464 | ||
fc4df999 | 2465 | static int io_sync_file_range(struct io_kiocb *req, struct io_kiocb **nxt, |
5d17b4a4 JA |
2466 | bool force_nonblock) |
2467 | { | |
8ed8d3c3 | 2468 | struct io_wq_work *work, *old_work; |
5d17b4a4 JA |
2469 | |
2470 | /* sync_file_range always requires a blocking context */ | |
8ed8d3c3 JA |
2471 | if (force_nonblock) { |
2472 | io_put_req(req); | |
2473 | req->work.func = io_sync_file_range_finish; | |
5d17b4a4 | 2474 | return -EAGAIN; |
8ed8d3c3 | 2475 | } |
5d17b4a4 | 2476 | |
8ed8d3c3 JA |
2477 | work = old_work = &req->work; |
2478 | io_sync_file_range_finish(&work); | |
2479 | if (work && work != old_work) | |
2480 | *nxt = container_of(work, struct io_kiocb, work); | |
5d17b4a4 JA |
2481 | return 0; |
2482 | } | |
2483 | ||
b7bb4f7d JA |
2484 | #if defined(CONFIG_NET) |
2485 | static void io_sendrecv_async(struct io_wq_work **workptr) | |
2486 | { | |
2487 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2488 | struct iovec *iov = NULL; | |
2489 | ||
2490 | if (req->io->rw.iov != req->io->rw.fast_iov) | |
2491 | iov = req->io->msg.iov; | |
2492 | io_wq_submit_work(workptr); | |
2493 | kfree(iov); | |
2494 | } | |
2495 | #endif | |
2496 | ||
3529d8c2 | 2497 | static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
03b1230c | 2498 | { |
0fa03c62 | 2499 | #if defined(CONFIG_NET) |
e47293fd | 2500 | struct io_sr_msg *sr = &req->sr_msg; |
3529d8c2 | 2501 | struct io_async_ctx *io = req->io; |
03b1230c | 2502 | |
e47293fd JA |
2503 | sr->msg_flags = READ_ONCE(sqe->msg_flags); |
2504 | sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr)); | |
3529d8c2 JA |
2505 | |
2506 | if (!io) | |
2507 | return 0; | |
2508 | ||
d9688565 | 2509 | io->msg.iov = io->msg.fast_iov; |
3529d8c2 | 2510 | return sendmsg_copy_msghdr(&io->msg.msg, sr->msg, sr->msg_flags, |
e47293fd | 2511 | &io->msg.iov); |
03b1230c | 2512 | #else |
e47293fd | 2513 | return -EOPNOTSUPP; |
03b1230c JA |
2514 | #endif |
2515 | } | |
2516 | ||
fc4df999 JA |
2517 | static int io_sendmsg(struct io_kiocb *req, struct io_kiocb **nxt, |
2518 | bool force_nonblock) | |
aa1fa28f | 2519 | { |
03b1230c | 2520 | #if defined(CONFIG_NET) |
0b416c3e | 2521 | struct io_async_msghdr *kmsg = NULL; |
0fa03c62 JA |
2522 | struct socket *sock; |
2523 | int ret; | |
2524 | ||
2525 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) | |
2526 | return -EINVAL; | |
2527 | ||
2528 | sock = sock_from_file(req->file, &ret); | |
2529 | if (sock) { | |
b7bb4f7d | 2530 | struct io_async_ctx io; |
03b1230c | 2531 | struct sockaddr_storage addr; |
0fa03c62 JA |
2532 | unsigned flags; |
2533 | ||
03b1230c | 2534 | if (req->io) { |
0b416c3e JA |
2535 | kmsg = &req->io->msg; |
2536 | kmsg->msg.msg_name = &addr; | |
2537 | /* if iov is set, it's allocated already */ | |
2538 | if (!kmsg->iov) | |
2539 | kmsg->iov = kmsg->fast_iov; | |
2540 | kmsg->msg.msg_iter.iov = kmsg->iov; | |
03b1230c | 2541 | } else { |
3529d8c2 JA |
2542 | struct io_sr_msg *sr = &req->sr_msg; |
2543 | ||
0b416c3e JA |
2544 | kmsg = &io.msg; |
2545 | kmsg->msg.msg_name = &addr; | |
3529d8c2 JA |
2546 | |
2547 | io.msg.iov = io.msg.fast_iov; | |
2548 | ret = sendmsg_copy_msghdr(&io.msg.msg, sr->msg, | |
2549 | sr->msg_flags, &io.msg.iov); | |
03b1230c | 2550 | if (ret) |
3529d8c2 | 2551 | return ret; |
03b1230c | 2552 | } |
0fa03c62 | 2553 | |
e47293fd JA |
2554 | flags = req->sr_msg.msg_flags; |
2555 | if (flags & MSG_DONTWAIT) | |
2556 | req->flags |= REQ_F_NOWAIT; | |
2557 | else if (force_nonblock) | |
2558 | flags |= MSG_DONTWAIT; | |
2559 | ||
0b416c3e | 2560 | ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags); |
03b1230c | 2561 | if (force_nonblock && ret == -EAGAIN) { |
b7bb4f7d JA |
2562 | if (req->io) |
2563 | return -EAGAIN; | |
2564 | if (io_alloc_async_ctx(req)) | |
2565 | return -ENOMEM; | |
2566 | memcpy(&req->io->msg, &io.msg, sizeof(io.msg)); | |
2567 | req->work.func = io_sendrecv_async; | |
0b416c3e | 2568 | return -EAGAIN; |
03b1230c | 2569 | } |
441cdbd5 JA |
2570 | if (ret == -ERESTARTSYS) |
2571 | ret = -EINTR; | |
0fa03c62 JA |
2572 | } |
2573 | ||
b7bb4f7d | 2574 | if (!io_wq_current_is_worker() && kmsg && kmsg->iov != kmsg->fast_iov) |
0b416c3e | 2575 | kfree(kmsg->iov); |
78e19bbe | 2576 | io_cqring_add_event(req, ret); |
4e88d6e7 JA |
2577 | if (ret < 0) |
2578 | req_set_fail_links(req); | |
ec9c02ad | 2579 | io_put_req_find_next(req, nxt); |
5d17b4a4 | 2580 | return 0; |
03b1230c JA |
2581 | #else |
2582 | return -EOPNOTSUPP; | |
aa1fa28f | 2583 | #endif |
03b1230c | 2584 | } |
aa1fa28f | 2585 | |
3529d8c2 JA |
2586 | static int io_recvmsg_prep(struct io_kiocb *req, |
2587 | const struct io_uring_sqe *sqe) | |
aa1fa28f JA |
2588 | { |
2589 | #if defined(CONFIG_NET) | |
e47293fd | 2590 | struct io_sr_msg *sr = &req->sr_msg; |
3529d8c2 JA |
2591 | struct io_async_ctx *io = req->io; |
2592 | ||
2593 | sr->msg_flags = READ_ONCE(sqe->msg_flags); | |
2594 | sr->msg = u64_to_user_ptr(READ_ONCE(sqe->addr)); | |
06b76d44 | 2595 | |
3529d8c2 | 2596 | if (!io) |
06b76d44 | 2597 | return 0; |
03b1230c | 2598 | |
d9688565 | 2599 | io->msg.iov = io->msg.fast_iov; |
3529d8c2 | 2600 | return recvmsg_copy_msghdr(&io->msg.msg, sr->msg, sr->msg_flags, |
e47293fd | 2601 | &io->msg.uaddr, &io->msg.iov); |
aa1fa28f | 2602 | #else |
e47293fd | 2603 | return -EOPNOTSUPP; |
aa1fa28f JA |
2604 | #endif |
2605 | } | |
2606 | ||
fc4df999 JA |
2607 | static int io_recvmsg(struct io_kiocb *req, struct io_kiocb **nxt, |
2608 | bool force_nonblock) | |
aa1fa28f JA |
2609 | { |
2610 | #if defined(CONFIG_NET) | |
0b416c3e | 2611 | struct io_async_msghdr *kmsg = NULL; |
03b1230c JA |
2612 | struct socket *sock; |
2613 | int ret; | |
2614 | ||
2615 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) | |
2616 | return -EINVAL; | |
2617 | ||
2618 | sock = sock_from_file(req->file, &ret); | |
2619 | if (sock) { | |
b7bb4f7d | 2620 | struct io_async_ctx io; |
03b1230c | 2621 | struct sockaddr_storage addr; |
03b1230c JA |
2622 | unsigned flags; |
2623 | ||
03b1230c | 2624 | if (req->io) { |
0b416c3e JA |
2625 | kmsg = &req->io->msg; |
2626 | kmsg->msg.msg_name = &addr; | |
2627 | /* if iov is set, it's allocated already */ | |
2628 | if (!kmsg->iov) | |
2629 | kmsg->iov = kmsg->fast_iov; | |
2630 | kmsg->msg.msg_iter.iov = kmsg->iov; | |
03b1230c | 2631 | } else { |
3529d8c2 JA |
2632 | struct io_sr_msg *sr = &req->sr_msg; |
2633 | ||
0b416c3e JA |
2634 | kmsg = &io.msg; |
2635 | kmsg->msg.msg_name = &addr; | |
3529d8c2 JA |
2636 | |
2637 | io.msg.iov = io.msg.fast_iov; | |
2638 | ret = recvmsg_copy_msghdr(&io.msg.msg, sr->msg, | |
2639 | sr->msg_flags, &io.msg.uaddr, | |
2640 | &io.msg.iov); | |
03b1230c | 2641 | if (ret) |
3529d8c2 | 2642 | return ret; |
03b1230c JA |
2643 | } |
2644 | ||
e47293fd JA |
2645 | flags = req->sr_msg.msg_flags; |
2646 | if (flags & MSG_DONTWAIT) | |
2647 | req->flags |= REQ_F_NOWAIT; | |
2648 | else if (force_nonblock) | |
2649 | flags |= MSG_DONTWAIT; | |
2650 | ||
2651 | ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.msg, | |
2652 | kmsg->uaddr, flags); | |
03b1230c | 2653 | if (force_nonblock && ret == -EAGAIN) { |
b7bb4f7d JA |
2654 | if (req->io) |
2655 | return -EAGAIN; | |
2656 | if (io_alloc_async_ctx(req)) | |
2657 | return -ENOMEM; | |
2658 | memcpy(&req->io->msg, &io.msg, sizeof(io.msg)); | |
2659 | req->work.func = io_sendrecv_async; | |
0b416c3e | 2660 | return -EAGAIN; |
03b1230c JA |
2661 | } |
2662 | if (ret == -ERESTARTSYS) | |
2663 | ret = -EINTR; | |
2664 | } | |
2665 | ||
b7bb4f7d | 2666 | if (!io_wq_current_is_worker() && kmsg && kmsg->iov != kmsg->fast_iov) |
0b416c3e | 2667 | kfree(kmsg->iov); |
03b1230c | 2668 | io_cqring_add_event(req, ret); |
4e88d6e7 JA |
2669 | if (ret < 0) |
2670 | req_set_fail_links(req); | |
03b1230c JA |
2671 | io_put_req_find_next(req, nxt); |
2672 | return 0; | |
0fa03c62 JA |
2673 | #else |
2674 | return -EOPNOTSUPP; | |
2675 | #endif | |
2676 | } | |
5d17b4a4 | 2677 | |
3529d8c2 | 2678 | static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
17f2fe35 JA |
2679 | { |
2680 | #if defined(CONFIG_NET) | |
8ed8d3c3 JA |
2681 | struct io_accept *accept = &req->accept; |
2682 | ||
17f2fe35 JA |
2683 | if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) |
2684 | return -EINVAL; | |
8042d6ce | 2685 | if (sqe->ioprio || sqe->len || sqe->buf_index) |
17f2fe35 JA |
2686 | return -EINVAL; |
2687 | ||
d55e5f5b JA |
2688 | accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr)); |
2689 | accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2)); | |
8ed8d3c3 | 2690 | accept->flags = READ_ONCE(sqe->accept_flags); |
8ed8d3c3 JA |
2691 | return 0; |
2692 | #else | |
2693 | return -EOPNOTSUPP; | |
2694 | #endif | |
2695 | } | |
17f2fe35 | 2696 | |
8ed8d3c3 JA |
2697 | #if defined(CONFIG_NET) |
2698 | static int __io_accept(struct io_kiocb *req, struct io_kiocb **nxt, | |
2699 | bool force_nonblock) | |
2700 | { | |
2701 | struct io_accept *accept = &req->accept; | |
2702 | unsigned file_flags; | |
2703 | int ret; | |
2704 | ||
2705 | file_flags = force_nonblock ? O_NONBLOCK : 0; | |
2706 | ret = __sys_accept4_file(req->file, file_flags, accept->addr, | |
2707 | accept->addr_len, accept->flags); | |
2708 | if (ret == -EAGAIN && force_nonblock) | |
17f2fe35 | 2709 | return -EAGAIN; |
8e3cca12 JA |
2710 | if (ret == -ERESTARTSYS) |
2711 | ret = -EINTR; | |
4e88d6e7 JA |
2712 | if (ret < 0) |
2713 | req_set_fail_links(req); | |
78e19bbe | 2714 | io_cqring_add_event(req, ret); |
ec9c02ad | 2715 | io_put_req_find_next(req, nxt); |
17f2fe35 | 2716 | return 0; |
8ed8d3c3 JA |
2717 | } |
2718 | ||
2719 | static void io_accept_finish(struct io_wq_work **workptr) | |
2720 | { | |
2721 | struct io_kiocb *req = container_of(*workptr, struct io_kiocb, work); | |
2722 | struct io_kiocb *nxt = NULL; | |
2723 | ||
2724 | if (io_req_cancelled(req)) | |
2725 | return; | |
2726 | __io_accept(req, &nxt, false); | |
2727 | if (nxt) | |
78912934 | 2728 | io_wq_assign_next(workptr, nxt); |
8ed8d3c3 JA |
2729 | } |
2730 | #endif | |
2731 | ||
2732 | static int io_accept(struct io_kiocb *req, struct io_kiocb **nxt, | |
2733 | bool force_nonblock) | |
2734 | { | |
2735 | #if defined(CONFIG_NET) | |
2736 | int ret; | |
2737 | ||
8ed8d3c3 JA |
2738 | ret = __io_accept(req, nxt, force_nonblock); |
2739 | if (ret == -EAGAIN && force_nonblock) { | |
2740 | req->work.func = io_accept_finish; | |
2741 | req->work.flags |= IO_WQ_WORK_NEEDS_FILES; | |
2742 | io_put_req(req); | |
2743 | return -EAGAIN; | |
2744 | } | |
2745 | return 0; | |
0fa03c62 JA |
2746 | #else |
2747 | return -EOPNOTSUPP; | |
2748 | #endif | |
2749 | } | |
5d17b4a4 | 2750 | |
3529d8c2 | 2751 | static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
f499a021 JA |
2752 | { |
2753 | #if defined(CONFIG_NET) | |
3529d8c2 JA |
2754 | struct io_connect *conn = &req->connect; |
2755 | struct io_async_ctx *io = req->io; | |
f499a021 | 2756 | |
3fbb51c1 JA |
2757 | if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) |
2758 | return -EINVAL; | |
2759 | if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags) | |
2760 | return -EINVAL; | |
2761 | ||
3529d8c2 JA |
2762 | conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr)); |
2763 | conn->addr_len = READ_ONCE(sqe->addr2); | |
2764 | ||
2765 | if (!io) | |
2766 | return 0; | |
2767 | ||
2768 | return move_addr_to_kernel(conn->addr, conn->addr_len, | |
3fbb51c1 | 2769 | &io->connect.address); |
f499a021 | 2770 | #else |
3fbb51c1 | 2771 | return -EOPNOTSUPP; |
f499a021 JA |
2772 | #endif |
2773 | } | |
2774 | ||
fc4df999 JA |
2775 | static int io_connect(struct io_kiocb *req, struct io_kiocb **nxt, |
2776 | bool force_nonblock) | |
f8e85cf2 JA |
2777 | { |
2778 | #if defined(CONFIG_NET) | |
f499a021 | 2779 | struct io_async_ctx __io, *io; |
f8e85cf2 | 2780 | unsigned file_flags; |
3fbb51c1 | 2781 | int ret; |
f8e85cf2 | 2782 | |
f499a021 JA |
2783 | if (req->io) { |
2784 | io = req->io; | |
2785 | } else { | |
3529d8c2 JA |
2786 | ret = move_addr_to_kernel(req->connect.addr, |
2787 | req->connect.addr_len, | |
2788 | &__io.connect.address); | |
f499a021 JA |
2789 | if (ret) |
2790 | goto out; | |
2791 | io = &__io; | |
2792 | } | |
2793 | ||
3fbb51c1 JA |
2794 | file_flags = force_nonblock ? O_NONBLOCK : 0; |
2795 | ||
2796 | ret = __sys_connect_file(req->file, &io->connect.address, | |
2797 | req->connect.addr_len, file_flags); | |
87f80d62 | 2798 | if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) { |
b7bb4f7d JA |
2799 | if (req->io) |
2800 | return -EAGAIN; | |
2801 | if (io_alloc_async_ctx(req)) { | |
f499a021 JA |
2802 | ret = -ENOMEM; |
2803 | goto out; | |
2804 | } | |
b7bb4f7d | 2805 | memcpy(&req->io->connect, &__io.connect, sizeof(__io.connect)); |
f8e85cf2 | 2806 | return -EAGAIN; |
f499a021 | 2807 | } |
f8e85cf2 JA |
2808 | if (ret == -ERESTARTSYS) |
2809 | ret = -EINTR; | |
f499a021 | 2810 | out: |
4e88d6e7 JA |
2811 | if (ret < 0) |
2812 | req_set_fail_links(req); | |
f8e85cf2 JA |
2813 | io_cqring_add_event(req, ret); |
2814 | io_put_req_find_next(req, nxt); | |
2815 | return 0; | |
2816 | #else | |
2817 | return -EOPNOTSUPP; | |
2818 | #endif | |
2819 | } | |
2820 | ||
221c5eb2 JA |
2821 | static void io_poll_remove_one(struct io_kiocb *req) |
2822 | { | |
2823 | struct io_poll_iocb *poll = &req->poll; | |
2824 | ||
2825 | spin_lock(&poll->head->lock); | |
2826 | WRITE_ONCE(poll->canceled, true); | |
392edb45 JA |
2827 | if (!list_empty(&poll->wait.entry)) { |
2828 | list_del_init(&poll->wait.entry); | |
a197f664 | 2829 | io_queue_async_work(req); |
221c5eb2 JA |
2830 | } |
2831 | spin_unlock(&poll->head->lock); | |
78076bb6 | 2832 | hash_del(&req->hash_node); |
221c5eb2 JA |
2833 | } |
2834 | ||
2835 | static void io_poll_remove_all(struct io_ring_ctx *ctx) | |
2836 | { | |
78076bb6 | 2837 | struct hlist_node *tmp; |
221c5eb2 | 2838 | struct io_kiocb *req; |
78076bb6 | 2839 | int i; |
221c5eb2 JA |
2840 | |
2841 | spin_lock_irq(&ctx->completion_lock); | |
78076bb6 JA |
2842 | for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) { |
2843 | struct hlist_head *list; | |
2844 | ||
2845 | list = &ctx->cancel_hash[i]; | |
2846 | hlist_for_each_entry_safe(req, tmp, list, hash_node) | |
2847 | io_poll_remove_one(req); | |
221c5eb2 JA |
2848 | } |
2849 | spin_unlock_irq(&ctx->completion_lock); | |
2850 | } | |
2851 | ||
47f46768 JA |
2852 | static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr) |
2853 | { | |
78076bb6 | 2854 | struct hlist_head *list; |
47f46768 JA |
2855 | struct io_kiocb *req; |
2856 | ||
78076bb6 JA |
2857 | list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)]; |
2858 | hlist_for_each_entry(req, list, hash_node) { | |
2859 | if (sqe_addr == req->user_data) { | |
eac406c6 JA |
2860 | io_poll_remove_one(req); |
2861 | return 0; | |
2862 | } | |
47f46768 JA |
2863 | } |
2864 | ||
2865 | return -ENOENT; | |
2866 | } | |
2867 | ||
3529d8c2 JA |
2868 | static int io_poll_remove_prep(struct io_kiocb *req, |
2869 | const struct io_uring_sqe *sqe) | |
0969e783 | 2870 | { |
0969e783 JA |
2871 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) |
2872 | return -EINVAL; | |
2873 | if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index || | |
2874 | sqe->poll_events) | |
2875 | return -EINVAL; | |
2876 | ||
2877 | req->poll.addr = READ_ONCE(sqe->addr); | |
0969e783 JA |
2878 | return 0; |
2879 | } | |
2880 | ||
221c5eb2 JA |
2881 | /* |
2882 | * Find a running poll command that matches one specified in sqe->addr, | |
2883 | * and remove it if found. | |
2884 | */ | |
fc4df999 | 2885 | static int io_poll_remove(struct io_kiocb *req) |
221c5eb2 JA |
2886 | { |
2887 | struct io_ring_ctx *ctx = req->ctx; | |
0969e783 | 2888 | u64 addr; |
47f46768 | 2889 | int ret; |
221c5eb2 | 2890 | |
0969e783 | 2891 | addr = req->poll.addr; |
221c5eb2 | 2892 | spin_lock_irq(&ctx->completion_lock); |
0969e783 | 2893 | ret = io_poll_cancel(ctx, addr); |
221c5eb2 JA |
2894 | spin_unlock_irq(&ctx->completion_lock); |
2895 | ||
78e19bbe | 2896 | io_cqring_add_event(req, ret); |
4e88d6e7 JA |
2897 | if (ret < 0) |
2898 | req_set_fail_links(req); | |
e65ef56d | 2899 | io_put_req(req); |
221c5eb2 JA |
2900 | return 0; |
2901 | } | |
2902 | ||
b0dd8a41 | 2903 | static void io_poll_complete(struct io_kiocb *req, __poll_t mask, int error) |
221c5eb2 | 2904 | { |
a197f664 JL |
2905 | struct io_ring_ctx *ctx = req->ctx; |
2906 | ||
8c838788 | 2907 | req->poll.done = true; |
b0dd8a41 JA |
2908 | if (error) |
2909 | io_cqring_fill_event(req, error); | |
2910 | else | |
2911 | io_cqring_fill_event(req, mangle_poll(mask)); | |
8c838788 | 2912 | io_commit_cqring(ctx); |
221c5eb2 JA |
2913 | } |
2914 | ||
561fb04a | 2915 | static void io_poll_complete_work(struct io_wq_work **workptr) |
221c5eb2 | 2916 | { |
561fb04a | 2917 | struct io_wq_work *work = *workptr; |
221c5eb2 JA |
2918 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); |
2919 | struct io_poll_iocb *poll = &req->poll; | |
2920 | struct poll_table_struct pt = { ._key = poll->events }; | |
2921 | struct io_ring_ctx *ctx = req->ctx; | |
89723d0b | 2922 | struct io_kiocb *nxt = NULL; |
221c5eb2 | 2923 | __poll_t mask = 0; |
b0dd8a41 | 2924 | int ret = 0; |
221c5eb2 | 2925 | |
b0dd8a41 | 2926 | if (work->flags & IO_WQ_WORK_CANCEL) { |
561fb04a | 2927 | WRITE_ONCE(poll->canceled, true); |
b0dd8a41 JA |
2928 | ret = -ECANCELED; |
2929 | } else if (READ_ONCE(poll->canceled)) { | |
2930 | ret = -ECANCELED; | |
2931 | } | |
561fb04a | 2932 | |
b0dd8a41 | 2933 | if (ret != -ECANCELED) |
221c5eb2 JA |
2934 | mask = vfs_poll(poll->file, &pt) & poll->events; |
2935 | ||
2936 | /* | |
2937 | * Note that ->ki_cancel callers also delete iocb from active_reqs after | |
2938 | * calling ->ki_cancel. We need the ctx_lock roundtrip here to | |
2939 | * synchronize with them. In the cancellation case the list_del_init | |
2940 | * itself is not actually needed, but harmless so we keep it in to | |
2941 | * avoid further branches in the fast path. | |
2942 | */ | |
2943 | spin_lock_irq(&ctx->completion_lock); | |
b0dd8a41 | 2944 | if (!mask && ret != -ECANCELED) { |
392edb45 | 2945 | add_wait_queue(poll->head, &poll->wait); |
221c5eb2 JA |
2946 | spin_unlock_irq(&ctx->completion_lock); |
2947 | return; | |
2948 | } | |
78076bb6 | 2949 | hash_del(&req->hash_node); |
b0dd8a41 | 2950 | io_poll_complete(req, mask, ret); |
221c5eb2 JA |
2951 | spin_unlock_irq(&ctx->completion_lock); |
2952 | ||
8c838788 | 2953 | io_cqring_ev_posted(ctx); |
89723d0b | 2954 | |
4e88d6e7 JA |
2955 | if (ret < 0) |
2956 | req_set_fail_links(req); | |
ec9c02ad | 2957 | io_put_req_find_next(req, &nxt); |
89723d0b | 2958 | if (nxt) |
78912934 | 2959 | io_wq_assign_next(workptr, nxt); |
221c5eb2 JA |
2960 | } |
2961 | ||
2962 | static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, | |
2963 | void *key) | |
2964 | { | |
e944475e | 2965 | struct io_poll_iocb *poll = wait->private; |
221c5eb2 JA |
2966 | struct io_kiocb *req = container_of(poll, struct io_kiocb, poll); |
2967 | struct io_ring_ctx *ctx = req->ctx; | |
2968 | __poll_t mask = key_to_poll(key); | |
8c838788 | 2969 | unsigned long flags; |
221c5eb2 JA |
2970 | |
2971 | /* for instances that support it check for an event match first: */ | |
8c838788 JA |
2972 | if (mask && !(mask & poll->events)) |
2973 | return 0; | |
221c5eb2 | 2974 | |
392edb45 | 2975 | list_del_init(&poll->wait.entry); |
221c5eb2 | 2976 | |
7c9e7f0f JA |
2977 | /* |
2978 | * Run completion inline if we can. We're using trylock here because | |
2979 | * we are violating the completion_lock -> poll wq lock ordering. | |
2980 | * If we have a link timeout we're going to need the completion_lock | |
2981 | * for finalizing the request, mark us as having grabbed that already. | |
2982 | */ | |
8c838788 | 2983 | if (mask && spin_trylock_irqsave(&ctx->completion_lock, flags)) { |
78076bb6 | 2984 | hash_del(&req->hash_node); |
b0dd8a41 | 2985 | io_poll_complete(req, mask, 0); |
7c9e7f0f JA |
2986 | req->flags |= REQ_F_COMP_LOCKED; |
2987 | io_put_req(req); | |
8c838788 | 2988 | spin_unlock_irqrestore(&ctx->completion_lock, flags); |
221c5eb2 | 2989 | |
8c838788 | 2990 | io_cqring_ev_posted(ctx); |
8c838788 | 2991 | } else { |
a197f664 | 2992 | io_queue_async_work(req); |
221c5eb2 JA |
2993 | } |
2994 | ||
221c5eb2 JA |
2995 | return 1; |
2996 | } | |
2997 | ||
2998 | struct io_poll_table { | |
2999 | struct poll_table_struct pt; | |
3000 | struct io_kiocb *req; | |
3001 | int error; | |
3002 | }; | |
3003 | ||
3004 | static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head, | |
3005 | struct poll_table_struct *p) | |
3006 | { | |
3007 | struct io_poll_table *pt = container_of(p, struct io_poll_table, pt); | |
3008 | ||
3009 | if (unlikely(pt->req->poll.head)) { | |
3010 | pt->error = -EINVAL; | |
3011 | return; | |
3012 | } | |
3013 | ||
3014 | pt->error = 0; | |
3015 | pt->req->poll.head = head; | |
392edb45 | 3016 | add_wait_queue(head, &pt->req->poll.wait); |
221c5eb2 JA |
3017 | } |
3018 | ||
eac406c6 JA |
3019 | static void io_poll_req_insert(struct io_kiocb *req) |
3020 | { | |
3021 | struct io_ring_ctx *ctx = req->ctx; | |
78076bb6 JA |
3022 | struct hlist_head *list; |
3023 | ||
3024 | list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)]; | |
3025 | hlist_add_head(&req->hash_node, list); | |
eac406c6 JA |
3026 | } |
3027 | ||
3529d8c2 | 3028 | static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
221c5eb2 JA |
3029 | { |
3030 | struct io_poll_iocb *poll = &req->poll; | |
221c5eb2 | 3031 | u16 events; |
221c5eb2 JA |
3032 | |
3033 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) | |
3034 | return -EINVAL; | |
3035 | if (sqe->addr || sqe->ioprio || sqe->off || sqe->len || sqe->buf_index) | |
3036 | return -EINVAL; | |
09bb8394 JA |
3037 | if (!poll->file) |
3038 | return -EBADF; | |
221c5eb2 | 3039 | |
221c5eb2 JA |
3040 | events = READ_ONCE(sqe->poll_events); |
3041 | poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP; | |
0969e783 JA |
3042 | return 0; |
3043 | } | |
3044 | ||
3045 | static int io_poll_add(struct io_kiocb *req, struct io_kiocb **nxt) | |
3046 | { | |
3047 | struct io_poll_iocb *poll = &req->poll; | |
3048 | struct io_ring_ctx *ctx = req->ctx; | |
3049 | struct io_poll_table ipt; | |
3050 | bool cancel = false; | |
3051 | __poll_t mask; | |
0969e783 JA |
3052 | |
3053 | INIT_IO_WORK(&req->work, io_poll_complete_work); | |
78076bb6 | 3054 | INIT_HLIST_NODE(&req->hash_node); |
221c5eb2 | 3055 | |
221c5eb2 | 3056 | poll->head = NULL; |
8c838788 | 3057 | poll->done = false; |
221c5eb2 JA |
3058 | poll->canceled = false; |
3059 | ||
3060 | ipt.pt._qproc = io_poll_queue_proc; | |
3061 | ipt.pt._key = poll->events; | |
3062 | ipt.req = req; | |
3063 | ipt.error = -EINVAL; /* same as no support for IOCB_CMD_POLL */ | |
3064 | ||
3065 | /* initialized the list so that we can do list_empty checks */ | |
392edb45 JA |
3066 | INIT_LIST_HEAD(&poll->wait.entry); |
3067 | init_waitqueue_func_entry(&poll->wait, io_poll_wake); | |
3068 | poll->wait.private = poll; | |
221c5eb2 | 3069 | |
36703247 JA |
3070 | INIT_LIST_HEAD(&req->list); |
3071 | ||
221c5eb2 | 3072 | mask = vfs_poll(poll->file, &ipt.pt) & poll->events; |
221c5eb2 JA |
3073 | |
3074 | spin_lock_irq(&ctx->completion_lock); | |
8c838788 JA |
3075 | if (likely(poll->head)) { |
3076 | spin_lock(&poll->head->lock); | |
392edb45 | 3077 | if (unlikely(list_empty(&poll->wait.entry))) { |
8c838788 JA |
3078 | if (ipt.error) |
3079 | cancel = true; | |
3080 | ipt.error = 0; | |
3081 | mask = 0; | |
3082 | } | |
3083 | if (mask || ipt.error) | |
392edb45 | 3084 | list_del_init(&poll->wait.entry); |
8c838788 JA |
3085 | else if (cancel) |
3086 | WRITE_ONCE(poll->canceled, true); | |
3087 | else if (!poll->done) /* actually waiting for an event */ | |
eac406c6 | 3088 | io_poll_req_insert(req); |
8c838788 JA |
3089 | spin_unlock(&poll->head->lock); |
3090 | } | |
3091 | if (mask) { /* no async, we'd stolen it */ | |
221c5eb2 | 3092 | ipt.error = 0; |
b0dd8a41 | 3093 | io_poll_complete(req, mask, 0); |
221c5eb2 | 3094 | } |
221c5eb2 JA |
3095 | spin_unlock_irq(&ctx->completion_lock); |
3096 | ||
8c838788 JA |
3097 | if (mask) { |
3098 | io_cqring_ev_posted(ctx); | |
ec9c02ad | 3099 | io_put_req_find_next(req, nxt); |
221c5eb2 | 3100 | } |
8c838788 | 3101 | return ipt.error; |
221c5eb2 JA |
3102 | } |
3103 | ||
5262f567 JA |
3104 | static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer) |
3105 | { | |
ad8a48ac JA |
3106 | struct io_timeout_data *data = container_of(timer, |
3107 | struct io_timeout_data, timer); | |
3108 | struct io_kiocb *req = data->req; | |
3109 | struct io_ring_ctx *ctx = req->ctx; | |
5262f567 JA |
3110 | unsigned long flags; |
3111 | ||
5262f567 JA |
3112 | atomic_inc(&ctx->cq_timeouts); |
3113 | ||
3114 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
ef03681a | 3115 | /* |
11365043 JA |
3116 | * We could be racing with timeout deletion. If the list is empty, |
3117 | * then timeout lookup already found it and will be handling it. | |
ef03681a | 3118 | */ |
842f9612 | 3119 | if (!list_empty(&req->list)) { |
11365043 | 3120 | struct io_kiocb *prev; |
5262f567 | 3121 | |
11365043 JA |
3122 | /* |
3123 | * Adjust the reqs sequence before the current one because it | |
d195a66e | 3124 | * will consume a slot in the cq_ring and the cq_tail |
11365043 JA |
3125 | * pointer will be increased, otherwise other timeout reqs may |
3126 | * return in advance without waiting for enough wait_nr. | |
3127 | */ | |
3128 | prev = req; | |
3129 | list_for_each_entry_continue_reverse(prev, &ctx->timeout_list, list) | |
3130 | prev->sequence++; | |
11365043 | 3131 | list_del_init(&req->list); |
11365043 | 3132 | } |
5262f567 | 3133 | |
78e19bbe | 3134 | io_cqring_fill_event(req, -ETIME); |
5262f567 JA |
3135 | io_commit_cqring(ctx); |
3136 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
3137 | ||
3138 | io_cqring_ev_posted(ctx); | |
4e88d6e7 | 3139 | req_set_fail_links(req); |
5262f567 JA |
3140 | io_put_req(req); |
3141 | return HRTIMER_NORESTART; | |
3142 | } | |
3143 | ||
47f46768 JA |
3144 | static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data) |
3145 | { | |
3146 | struct io_kiocb *req; | |
3147 | int ret = -ENOENT; | |
3148 | ||
3149 | list_for_each_entry(req, &ctx->timeout_list, list) { | |
3150 | if (user_data == req->user_data) { | |
3151 | list_del_init(&req->list); | |
3152 | ret = 0; | |
3153 | break; | |
3154 | } | |
3155 | } | |
3156 | ||
3157 | if (ret == -ENOENT) | |
3158 | return ret; | |
3159 | ||
2d28390a | 3160 | ret = hrtimer_try_to_cancel(&req->io->timeout.timer); |
47f46768 JA |
3161 | if (ret == -1) |
3162 | return -EALREADY; | |
3163 | ||
4e88d6e7 | 3164 | req_set_fail_links(req); |
47f46768 JA |
3165 | io_cqring_fill_event(req, -ECANCELED); |
3166 | io_put_req(req); | |
3167 | return 0; | |
3168 | } | |
3169 | ||
3529d8c2 JA |
3170 | static int io_timeout_remove_prep(struct io_kiocb *req, |
3171 | const struct io_uring_sqe *sqe) | |
b29472ee | 3172 | { |
b29472ee JA |
3173 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) |
3174 | return -EINVAL; | |
3175 | if (sqe->flags || sqe->ioprio || sqe->buf_index || sqe->len) | |
3176 | return -EINVAL; | |
3177 | ||
3178 | req->timeout.addr = READ_ONCE(sqe->addr); | |
3179 | req->timeout.flags = READ_ONCE(sqe->timeout_flags); | |
3180 | if (req->timeout.flags) | |
3181 | return -EINVAL; | |
3182 | ||
b29472ee JA |
3183 | return 0; |
3184 | } | |
3185 | ||
11365043 JA |
3186 | /* |
3187 | * Remove or update an existing timeout command | |
3188 | */ | |
fc4df999 | 3189 | static int io_timeout_remove(struct io_kiocb *req) |
11365043 JA |
3190 | { |
3191 | struct io_ring_ctx *ctx = req->ctx; | |
47f46768 | 3192 | int ret; |
11365043 | 3193 | |
11365043 | 3194 | spin_lock_irq(&ctx->completion_lock); |
b29472ee | 3195 | ret = io_timeout_cancel(ctx, req->timeout.addr); |
11365043 | 3196 | |
47f46768 | 3197 | io_cqring_fill_event(req, ret); |
11365043 JA |
3198 | io_commit_cqring(ctx); |
3199 | spin_unlock_irq(&ctx->completion_lock); | |
5262f567 | 3200 | io_cqring_ev_posted(ctx); |
4e88d6e7 JA |
3201 | if (ret < 0) |
3202 | req_set_fail_links(req); | |
ec9c02ad | 3203 | io_put_req(req); |
11365043 | 3204 | return 0; |
5262f567 JA |
3205 | } |
3206 | ||
3529d8c2 | 3207 | static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
2d28390a | 3208 | bool is_timeout_link) |
5262f567 | 3209 | { |
ad8a48ac | 3210 | struct io_timeout_data *data; |
a41525ab | 3211 | unsigned flags; |
5262f567 | 3212 | |
ad8a48ac | 3213 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) |
5262f567 | 3214 | return -EINVAL; |
ad8a48ac | 3215 | if (sqe->ioprio || sqe->buf_index || sqe->len != 1) |
a41525ab | 3216 | return -EINVAL; |
2d28390a JA |
3217 | if (sqe->off && is_timeout_link) |
3218 | return -EINVAL; | |
a41525ab JA |
3219 | flags = READ_ONCE(sqe->timeout_flags); |
3220 | if (flags & ~IORING_TIMEOUT_ABS) | |
5262f567 | 3221 | return -EINVAL; |
bdf20073 | 3222 | |
26a61679 JA |
3223 | req->timeout.count = READ_ONCE(sqe->off); |
3224 | ||
3529d8c2 | 3225 | if (!req->io && io_alloc_async_ctx(req)) |
26a61679 JA |
3226 | return -ENOMEM; |
3227 | ||
3228 | data = &req->io->timeout; | |
ad8a48ac | 3229 | data->req = req; |
ad8a48ac JA |
3230 | req->flags |= REQ_F_TIMEOUT; |
3231 | ||
3232 | if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr))) | |
5262f567 JA |
3233 | return -EFAULT; |
3234 | ||
11365043 | 3235 | if (flags & IORING_TIMEOUT_ABS) |
ad8a48ac | 3236 | data->mode = HRTIMER_MODE_ABS; |
11365043 | 3237 | else |
ad8a48ac | 3238 | data->mode = HRTIMER_MODE_REL; |
11365043 | 3239 | |
ad8a48ac JA |
3240 | hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode); |
3241 | return 0; | |
3242 | } | |
3243 | ||
fc4df999 | 3244 | static int io_timeout(struct io_kiocb *req) |
ad8a48ac JA |
3245 | { |
3246 | unsigned count; | |
3247 | struct io_ring_ctx *ctx = req->ctx; | |
3248 | struct io_timeout_data *data; | |
3249 | struct list_head *entry; | |
3250 | unsigned span = 0; | |
ad8a48ac | 3251 | |
2d28390a | 3252 | data = &req->io->timeout; |
93bd25bb | 3253 | |
5262f567 JA |
3254 | /* |
3255 | * sqe->off holds how many events that need to occur for this | |
93bd25bb JA |
3256 | * timeout event to be satisfied. If it isn't set, then this is |
3257 | * a pure timeout request, sequence isn't used. | |
5262f567 | 3258 | */ |
26a61679 | 3259 | count = req->timeout.count; |
93bd25bb JA |
3260 | if (!count) { |
3261 | req->flags |= REQ_F_TIMEOUT_NOSEQ; | |
3262 | spin_lock_irq(&ctx->completion_lock); | |
3263 | entry = ctx->timeout_list.prev; | |
3264 | goto add; | |
3265 | } | |
5262f567 JA |
3266 | |
3267 | req->sequence = ctx->cached_sq_head + count - 1; | |
2d28390a | 3268 | data->seq_offset = count; |
5262f567 JA |
3269 | |
3270 | /* | |
3271 | * Insertion sort, ensuring the first entry in the list is always | |
3272 | * the one we need first. | |
3273 | */ | |
5262f567 JA |
3274 | spin_lock_irq(&ctx->completion_lock); |
3275 | list_for_each_prev(entry, &ctx->timeout_list) { | |
3276 | struct io_kiocb *nxt = list_entry(entry, struct io_kiocb, list); | |
5da0fb1a | 3277 | unsigned nxt_sq_head; |
3278 | long long tmp, tmp_nxt; | |
2d28390a | 3279 | u32 nxt_offset = nxt->io->timeout.seq_offset; |
5262f567 | 3280 | |
93bd25bb JA |
3281 | if (nxt->flags & REQ_F_TIMEOUT_NOSEQ) |
3282 | continue; | |
3283 | ||
5da0fb1a | 3284 | /* |
3285 | * Since cached_sq_head + count - 1 can overflow, use type long | |
3286 | * long to store it. | |
3287 | */ | |
3288 | tmp = (long long)ctx->cached_sq_head + count - 1; | |
cc42e0ac PB |
3289 | nxt_sq_head = nxt->sequence - nxt_offset + 1; |
3290 | tmp_nxt = (long long)nxt_sq_head + nxt_offset - 1; | |
5da0fb1a | 3291 | |
3292 | /* | |
3293 | * cached_sq_head may overflow, and it will never overflow twice | |
3294 | * once there is some timeout req still be valid. | |
3295 | */ | |
3296 | if (ctx->cached_sq_head < nxt_sq_head) | |
8b07a65a | 3297 | tmp += UINT_MAX; |
5da0fb1a | 3298 | |
a1f58ba4 | 3299 | if (tmp > tmp_nxt) |
5262f567 | 3300 | break; |
a1f58ba4 | 3301 | |
3302 | /* | |
3303 | * Sequence of reqs after the insert one and itself should | |
3304 | * be adjusted because each timeout req consumes a slot. | |
3305 | */ | |
3306 | span++; | |
3307 | nxt->sequence++; | |
5262f567 | 3308 | } |
a1f58ba4 | 3309 | req->sequence -= span; |
93bd25bb | 3310 | add: |
5262f567 | 3311 | list_add(&req->list, entry); |
ad8a48ac JA |
3312 | data->timer.function = io_timeout_fn; |
3313 | hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode); | |
5262f567 | 3314 | spin_unlock_irq(&ctx->completion_lock); |
5262f567 JA |
3315 | return 0; |
3316 | } | |
5262f567 | 3317 | |
62755e35 JA |
3318 | static bool io_cancel_cb(struct io_wq_work *work, void *data) |
3319 | { | |
3320 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); | |
3321 | ||
3322 | return req->user_data == (unsigned long) data; | |
3323 | } | |
3324 | ||
e977d6d3 | 3325 | static int io_async_cancel_one(struct io_ring_ctx *ctx, void *sqe_addr) |
62755e35 | 3326 | { |
62755e35 | 3327 | enum io_wq_cancel cancel_ret; |
62755e35 JA |
3328 | int ret = 0; |
3329 | ||
62755e35 JA |
3330 | cancel_ret = io_wq_cancel_cb(ctx->io_wq, io_cancel_cb, sqe_addr); |
3331 | switch (cancel_ret) { | |
3332 | case IO_WQ_CANCEL_OK: | |
3333 | ret = 0; | |
3334 | break; | |
3335 | case IO_WQ_CANCEL_RUNNING: | |
3336 | ret = -EALREADY; | |
3337 | break; | |
3338 | case IO_WQ_CANCEL_NOTFOUND: | |
3339 | ret = -ENOENT; | |
3340 | break; | |
3341 | } | |
3342 | ||
e977d6d3 JA |
3343 | return ret; |
3344 | } | |
3345 | ||
47f46768 JA |
3346 | static void io_async_find_and_cancel(struct io_ring_ctx *ctx, |
3347 | struct io_kiocb *req, __u64 sqe_addr, | |
b0dd8a41 | 3348 | struct io_kiocb **nxt, int success_ret) |
47f46768 JA |
3349 | { |
3350 | unsigned long flags; | |
3351 | int ret; | |
3352 | ||
3353 | ret = io_async_cancel_one(ctx, (void *) (unsigned long) sqe_addr); | |
3354 | if (ret != -ENOENT) { | |
3355 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
3356 | goto done; | |
3357 | } | |
3358 | ||
3359 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
3360 | ret = io_timeout_cancel(ctx, sqe_addr); | |
3361 | if (ret != -ENOENT) | |
3362 | goto done; | |
3363 | ret = io_poll_cancel(ctx, sqe_addr); | |
3364 | done: | |
b0dd8a41 JA |
3365 | if (!ret) |
3366 | ret = success_ret; | |
47f46768 JA |
3367 | io_cqring_fill_event(req, ret); |
3368 | io_commit_cqring(ctx); | |
3369 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
3370 | io_cqring_ev_posted(ctx); | |
3371 | ||
4e88d6e7 JA |
3372 | if (ret < 0) |
3373 | req_set_fail_links(req); | |
47f46768 JA |
3374 | io_put_req_find_next(req, nxt); |
3375 | } | |
3376 | ||
3529d8c2 JA |
3377 | static int io_async_cancel_prep(struct io_kiocb *req, |
3378 | const struct io_uring_sqe *sqe) | |
e977d6d3 | 3379 | { |
fbf23849 | 3380 | if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) |
e977d6d3 JA |
3381 | return -EINVAL; |
3382 | if (sqe->flags || sqe->ioprio || sqe->off || sqe->len || | |
3383 | sqe->cancel_flags) | |
3384 | return -EINVAL; | |
3385 | ||
fbf23849 JA |
3386 | req->cancel.addr = READ_ONCE(sqe->addr); |
3387 | return 0; | |
3388 | } | |
3389 | ||
3390 | static int io_async_cancel(struct io_kiocb *req, struct io_kiocb **nxt) | |
3391 | { | |
3392 | struct io_ring_ctx *ctx = req->ctx; | |
fbf23849 JA |
3393 | |
3394 | io_async_find_and_cancel(ctx, req, req->cancel.addr, nxt, 0); | |
5262f567 JA |
3395 | return 0; |
3396 | } | |
3397 | ||
05f3fb3c JA |
3398 | static int io_files_update_prep(struct io_kiocb *req, |
3399 | const struct io_uring_sqe *sqe) | |
3400 | { | |
3401 | if (sqe->flags || sqe->ioprio || sqe->rw_flags) | |
3402 | return -EINVAL; | |
3403 | ||
3404 | req->files_update.offset = READ_ONCE(sqe->off); | |
3405 | req->files_update.nr_args = READ_ONCE(sqe->len); | |
3406 | if (!req->files_update.nr_args) | |
3407 | return -EINVAL; | |
3408 | req->files_update.arg = READ_ONCE(sqe->addr); | |
3409 | return 0; | |
3410 | } | |
3411 | ||
3412 | static int io_files_update(struct io_kiocb *req, bool force_nonblock) | |
3413 | { | |
3414 | struct io_ring_ctx *ctx = req->ctx; | |
3415 | struct io_uring_files_update up; | |
3416 | int ret; | |
3417 | ||
3418 | if (force_nonblock) { | |
3419 | req->work.flags |= IO_WQ_WORK_NEEDS_FILES; | |
3420 | return -EAGAIN; | |
3421 | } | |
3422 | ||
3423 | up.offset = req->files_update.offset; | |
3424 | up.fds = req->files_update.arg; | |
3425 | ||
3426 | mutex_lock(&ctx->uring_lock); | |
3427 | ret = __io_sqe_files_update(ctx, &up, req->files_update.nr_args); | |
3428 | mutex_unlock(&ctx->uring_lock); | |
3429 | ||
3430 | if (ret < 0) | |
3431 | req_set_fail_links(req); | |
3432 | io_cqring_add_event(req, ret); | |
3433 | io_put_req(req); | |
3434 | return 0; | |
3435 | } | |
3436 | ||
3529d8c2 JA |
3437 | static int io_req_defer_prep(struct io_kiocb *req, |
3438 | const struct io_uring_sqe *sqe) | |
f67676d1 | 3439 | { |
e781573e | 3440 | ssize_t ret = 0; |
f67676d1 | 3441 | |
d625c6ee | 3442 | switch (req->opcode) { |
e781573e JA |
3443 | case IORING_OP_NOP: |
3444 | break; | |
f67676d1 JA |
3445 | case IORING_OP_READV: |
3446 | case IORING_OP_READ_FIXED: | |
3529d8c2 | 3447 | ret = io_read_prep(req, sqe, true); |
f67676d1 JA |
3448 | break; |
3449 | case IORING_OP_WRITEV: | |
3450 | case IORING_OP_WRITE_FIXED: | |
3529d8c2 | 3451 | ret = io_write_prep(req, sqe, true); |
f67676d1 | 3452 | break; |
0969e783 | 3453 | case IORING_OP_POLL_ADD: |
3529d8c2 | 3454 | ret = io_poll_add_prep(req, sqe); |
0969e783 JA |
3455 | break; |
3456 | case IORING_OP_POLL_REMOVE: | |
3529d8c2 | 3457 | ret = io_poll_remove_prep(req, sqe); |
0969e783 | 3458 | break; |
8ed8d3c3 | 3459 | case IORING_OP_FSYNC: |
3529d8c2 | 3460 | ret = io_prep_fsync(req, sqe); |
8ed8d3c3 JA |
3461 | break; |
3462 | case IORING_OP_SYNC_FILE_RANGE: | |
3529d8c2 | 3463 | ret = io_prep_sfr(req, sqe); |
8ed8d3c3 | 3464 | break; |
03b1230c | 3465 | case IORING_OP_SENDMSG: |
3529d8c2 | 3466 | ret = io_sendmsg_prep(req, sqe); |
03b1230c JA |
3467 | break; |
3468 | case IORING_OP_RECVMSG: | |
3529d8c2 | 3469 | ret = io_recvmsg_prep(req, sqe); |
03b1230c | 3470 | break; |
f499a021 | 3471 | case IORING_OP_CONNECT: |
3529d8c2 | 3472 | ret = io_connect_prep(req, sqe); |
f499a021 | 3473 | break; |
2d28390a | 3474 | case IORING_OP_TIMEOUT: |
3529d8c2 | 3475 | ret = io_timeout_prep(req, sqe, false); |
b7bb4f7d | 3476 | break; |
b29472ee | 3477 | case IORING_OP_TIMEOUT_REMOVE: |
3529d8c2 | 3478 | ret = io_timeout_remove_prep(req, sqe); |
b29472ee | 3479 | break; |
fbf23849 | 3480 | case IORING_OP_ASYNC_CANCEL: |
3529d8c2 | 3481 | ret = io_async_cancel_prep(req, sqe); |
fbf23849 | 3482 | break; |
2d28390a | 3483 | case IORING_OP_LINK_TIMEOUT: |
3529d8c2 | 3484 | ret = io_timeout_prep(req, sqe, true); |
b7bb4f7d | 3485 | break; |
8ed8d3c3 | 3486 | case IORING_OP_ACCEPT: |
3529d8c2 | 3487 | ret = io_accept_prep(req, sqe); |
8ed8d3c3 | 3488 | break; |
d63d1b5e JA |
3489 | case IORING_OP_FALLOCATE: |
3490 | ret = io_fallocate_prep(req, sqe); | |
3491 | break; | |
15b71abe JA |
3492 | case IORING_OP_OPENAT: |
3493 | ret = io_openat_prep(req, sqe); | |
3494 | break; | |
b5dba59e JA |
3495 | case IORING_OP_CLOSE: |
3496 | ret = io_close_prep(req, sqe); | |
3497 | break; | |
05f3fb3c JA |
3498 | case IORING_OP_FILES_UPDATE: |
3499 | ret = io_files_update_prep(req, sqe); | |
3500 | break; | |
eddc7ef5 JA |
3501 | case IORING_OP_STATX: |
3502 | ret = io_statx_prep(req, sqe); | |
3503 | break; | |
f67676d1 | 3504 | default: |
e781573e JA |
3505 | printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n", |
3506 | req->opcode); | |
3507 | ret = -EINVAL; | |
b7bb4f7d | 3508 | break; |
f67676d1 JA |
3509 | } |
3510 | ||
b7bb4f7d | 3511 | return ret; |
f67676d1 JA |
3512 | } |
3513 | ||
3529d8c2 | 3514 | static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
de0617e4 | 3515 | { |
a197f664 | 3516 | struct io_ring_ctx *ctx = req->ctx; |
f67676d1 | 3517 | int ret; |
de0617e4 | 3518 | |
9d858b21 BL |
3519 | /* Still need defer if there is pending req in defer list. */ |
3520 | if (!req_need_defer(req) && list_empty(&ctx->defer_list)) | |
de0617e4 JA |
3521 | return 0; |
3522 | ||
3529d8c2 | 3523 | if (!req->io && io_alloc_async_ctx(req)) |
de0617e4 JA |
3524 | return -EAGAIN; |
3525 | ||
3529d8c2 | 3526 | ret = io_req_defer_prep(req, sqe); |
b7bb4f7d | 3527 | if (ret < 0) |
2d28390a | 3528 | return ret; |
2d28390a | 3529 | |
de0617e4 | 3530 | spin_lock_irq(&ctx->completion_lock); |
9d858b21 | 3531 | if (!req_need_defer(req) && list_empty(&ctx->defer_list)) { |
de0617e4 | 3532 | spin_unlock_irq(&ctx->completion_lock); |
de0617e4 JA |
3533 | return 0; |
3534 | } | |
3535 | ||
915967f6 | 3536 | trace_io_uring_defer(ctx, req, req->user_data); |
de0617e4 JA |
3537 | list_add_tail(&req->list, &ctx->defer_list); |
3538 | spin_unlock_irq(&ctx->completion_lock); | |
3539 | return -EIOCBQUEUED; | |
3540 | } | |
3541 | ||
3529d8c2 JA |
3542 | static int io_issue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
3543 | struct io_kiocb **nxt, bool force_nonblock) | |
2b188cc1 | 3544 | { |
a197f664 | 3545 | struct io_ring_ctx *ctx = req->ctx; |
d625c6ee | 3546 | int ret; |
2b188cc1 | 3547 | |
d625c6ee | 3548 | switch (req->opcode) { |
2b188cc1 | 3549 | case IORING_OP_NOP: |
78e19bbe | 3550 | ret = io_nop(req); |
2b188cc1 JA |
3551 | break; |
3552 | case IORING_OP_READV: | |
edafccee | 3553 | case IORING_OP_READ_FIXED: |
3529d8c2 JA |
3554 | if (sqe) { |
3555 | ret = io_read_prep(req, sqe, force_nonblock); | |
3556 | if (ret < 0) | |
3557 | break; | |
3558 | } | |
267bc904 | 3559 | ret = io_read(req, nxt, force_nonblock); |
edafccee | 3560 | break; |
3529d8c2 | 3561 | case IORING_OP_WRITEV: |
edafccee | 3562 | case IORING_OP_WRITE_FIXED: |
3529d8c2 JA |
3563 | if (sqe) { |
3564 | ret = io_write_prep(req, sqe, force_nonblock); | |
3565 | if (ret < 0) | |
3566 | break; | |
3567 | } | |
267bc904 | 3568 | ret = io_write(req, nxt, force_nonblock); |
2b188cc1 | 3569 | break; |
c992fe29 | 3570 | case IORING_OP_FSYNC: |
3529d8c2 JA |
3571 | if (sqe) { |
3572 | ret = io_prep_fsync(req, sqe); | |
3573 | if (ret < 0) | |
3574 | break; | |
3575 | } | |
fc4df999 | 3576 | ret = io_fsync(req, nxt, force_nonblock); |
c992fe29 | 3577 | break; |
221c5eb2 | 3578 | case IORING_OP_POLL_ADD: |
3529d8c2 JA |
3579 | if (sqe) { |
3580 | ret = io_poll_add_prep(req, sqe); | |
3581 | if (ret) | |
3582 | break; | |
3583 | } | |
fc4df999 | 3584 | ret = io_poll_add(req, nxt); |
221c5eb2 JA |
3585 | break; |
3586 | case IORING_OP_POLL_REMOVE: | |
3529d8c2 JA |
3587 | if (sqe) { |
3588 | ret = io_poll_remove_prep(req, sqe); | |
3589 | if (ret < 0) | |
3590 | break; | |
3591 | } | |
fc4df999 | 3592 | ret = io_poll_remove(req); |
221c5eb2 | 3593 | break; |
5d17b4a4 | 3594 | case IORING_OP_SYNC_FILE_RANGE: |
3529d8c2 JA |
3595 | if (sqe) { |
3596 | ret = io_prep_sfr(req, sqe); | |
3597 | if (ret < 0) | |
3598 | break; | |
3599 | } | |
fc4df999 | 3600 | ret = io_sync_file_range(req, nxt, force_nonblock); |
5d17b4a4 | 3601 | break; |
0fa03c62 | 3602 | case IORING_OP_SENDMSG: |
3529d8c2 JA |
3603 | if (sqe) { |
3604 | ret = io_sendmsg_prep(req, sqe); | |
3605 | if (ret < 0) | |
3606 | break; | |
3607 | } | |
fc4df999 | 3608 | ret = io_sendmsg(req, nxt, force_nonblock); |
0fa03c62 | 3609 | break; |
aa1fa28f | 3610 | case IORING_OP_RECVMSG: |
3529d8c2 JA |
3611 | if (sqe) { |
3612 | ret = io_recvmsg_prep(req, sqe); | |
3613 | if (ret) | |
3614 | break; | |
3615 | } | |
fc4df999 | 3616 | ret = io_recvmsg(req, nxt, force_nonblock); |
aa1fa28f | 3617 | break; |
5262f567 | 3618 | case IORING_OP_TIMEOUT: |
3529d8c2 JA |
3619 | if (sqe) { |
3620 | ret = io_timeout_prep(req, sqe, false); | |
3621 | if (ret) | |
3622 | break; | |
3623 | } | |
fc4df999 | 3624 | ret = io_timeout(req); |
5262f567 | 3625 | break; |
11365043 | 3626 | case IORING_OP_TIMEOUT_REMOVE: |
3529d8c2 JA |
3627 | if (sqe) { |
3628 | ret = io_timeout_remove_prep(req, sqe); | |
3629 | if (ret) | |
3630 | break; | |
3631 | } | |
fc4df999 | 3632 | ret = io_timeout_remove(req); |
11365043 | 3633 | break; |
17f2fe35 | 3634 | case IORING_OP_ACCEPT: |
3529d8c2 JA |
3635 | if (sqe) { |
3636 | ret = io_accept_prep(req, sqe); | |
3637 | if (ret) | |
3638 | break; | |
3639 | } | |
fc4df999 | 3640 | ret = io_accept(req, nxt, force_nonblock); |
17f2fe35 | 3641 | break; |
f8e85cf2 | 3642 | case IORING_OP_CONNECT: |
3529d8c2 JA |
3643 | if (sqe) { |
3644 | ret = io_connect_prep(req, sqe); | |
3645 | if (ret) | |
3646 | break; | |
3647 | } | |
fc4df999 | 3648 | ret = io_connect(req, nxt, force_nonblock); |
f8e85cf2 | 3649 | break; |
62755e35 | 3650 | case IORING_OP_ASYNC_CANCEL: |
3529d8c2 JA |
3651 | if (sqe) { |
3652 | ret = io_async_cancel_prep(req, sqe); | |
3653 | if (ret) | |
3654 | break; | |
3655 | } | |
fc4df999 | 3656 | ret = io_async_cancel(req, nxt); |
62755e35 | 3657 | break; |
d63d1b5e JA |
3658 | case IORING_OP_FALLOCATE: |
3659 | if (sqe) { | |
3660 | ret = io_fallocate_prep(req, sqe); | |
3661 | if (ret) | |
3662 | break; | |
3663 | } | |
3664 | ret = io_fallocate(req, nxt, force_nonblock); | |
3665 | break; | |
15b71abe JA |
3666 | case IORING_OP_OPENAT: |
3667 | if (sqe) { | |
3668 | ret = io_openat_prep(req, sqe); | |
3669 | if (ret) | |
3670 | break; | |
3671 | } | |
3672 | ret = io_openat(req, nxt, force_nonblock); | |
3673 | break; | |
b5dba59e JA |
3674 | case IORING_OP_CLOSE: |
3675 | if (sqe) { | |
3676 | ret = io_close_prep(req, sqe); | |
3677 | if (ret) | |
3678 | break; | |
3679 | } | |
3680 | ret = io_close(req, nxt, force_nonblock); | |
3681 | break; | |
05f3fb3c JA |
3682 | case IORING_OP_FILES_UPDATE: |
3683 | if (sqe) { | |
3684 | ret = io_files_update_prep(req, sqe); | |
3685 | if (ret) | |
3686 | break; | |
3687 | } | |
3688 | ret = io_files_update(req, force_nonblock); | |
3689 | break; | |
eddc7ef5 JA |
3690 | case IORING_OP_STATX: |
3691 | if (sqe) { | |
3692 | ret = io_statx_prep(req, sqe); | |
3693 | if (ret) | |
3694 | break; | |
3695 | } | |
3696 | ret = io_statx(req, nxt, force_nonblock); | |
3697 | break; | |
2b188cc1 JA |
3698 | default: |
3699 | ret = -EINVAL; | |
3700 | break; | |
3701 | } | |
3702 | ||
def596e9 JA |
3703 | if (ret) |
3704 | return ret; | |
3705 | ||
3706 | if (ctx->flags & IORING_SETUP_IOPOLL) { | |
11ba820b JA |
3707 | const bool in_async = io_wq_current_is_worker(); |
3708 | ||
9e645e11 | 3709 | if (req->result == -EAGAIN) |
def596e9 JA |
3710 | return -EAGAIN; |
3711 | ||
11ba820b JA |
3712 | /* workqueue context doesn't hold uring_lock, grab it now */ |
3713 | if (in_async) | |
3714 | mutex_lock(&ctx->uring_lock); | |
3715 | ||
def596e9 | 3716 | io_iopoll_req_issued(req); |
11ba820b JA |
3717 | |
3718 | if (in_async) | |
3719 | mutex_unlock(&ctx->uring_lock); | |
def596e9 JA |
3720 | } |
3721 | ||
3722 | return 0; | |
2b188cc1 JA |
3723 | } |
3724 | ||
561fb04a | 3725 | static void io_wq_submit_work(struct io_wq_work **workptr) |
2b188cc1 | 3726 | { |
561fb04a | 3727 | struct io_wq_work *work = *workptr; |
2b188cc1 | 3728 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); |
561fb04a JA |
3729 | struct io_kiocb *nxt = NULL; |
3730 | int ret = 0; | |
2b188cc1 | 3731 | |
0c9d5ccd JA |
3732 | /* if NO_CANCEL is set, we must still run the work */ |
3733 | if ((work->flags & (IO_WQ_WORK_CANCEL|IO_WQ_WORK_NO_CANCEL)) == | |
3734 | IO_WQ_WORK_CANCEL) { | |
561fb04a | 3735 | ret = -ECANCELED; |
0c9d5ccd | 3736 | } |
31b51510 | 3737 | |
561fb04a | 3738 | if (!ret) { |
cf6fd4bd PB |
3739 | req->has_user = (work->flags & IO_WQ_WORK_HAS_MM) != 0; |
3740 | req->in_async = true; | |
561fb04a | 3741 | do { |
3529d8c2 | 3742 | ret = io_issue_sqe(req, NULL, &nxt, false); |
561fb04a JA |
3743 | /* |
3744 | * We can get EAGAIN for polled IO even though we're | |
3745 | * forcing a sync submission from here, since we can't | |
3746 | * wait for request slots on the block side. | |
3747 | */ | |
3748 | if (ret != -EAGAIN) | |
3749 | break; | |
3750 | cond_resched(); | |
3751 | } while (1); | |
3752 | } | |
31b51510 | 3753 | |
561fb04a | 3754 | /* drop submission reference */ |
ec9c02ad | 3755 | io_put_req(req); |
817869d2 | 3756 | |
561fb04a | 3757 | if (ret) { |
4e88d6e7 | 3758 | req_set_fail_links(req); |
78e19bbe | 3759 | io_cqring_add_event(req, ret); |
817869d2 | 3760 | io_put_req(req); |
edafccee | 3761 | } |
2b188cc1 | 3762 | |
561fb04a | 3763 | /* if a dependent link is ready, pass it back */ |
78912934 JA |
3764 | if (!ret && nxt) |
3765 | io_wq_assign_next(workptr, nxt); | |
2b188cc1 JA |
3766 | } |
3767 | ||
9e3aa61a JA |
3768 | static bool io_req_op_valid(int op) |
3769 | { | |
3770 | return op >= IORING_OP_NOP && op < IORING_OP_LAST; | |
3771 | } | |
3772 | ||
15b71abe | 3773 | static int io_req_needs_file(struct io_kiocb *req, int fd) |
09bb8394 | 3774 | { |
d625c6ee | 3775 | switch (req->opcode) { |
09bb8394 JA |
3776 | case IORING_OP_NOP: |
3777 | case IORING_OP_POLL_REMOVE: | |
5683e540 | 3778 | case IORING_OP_TIMEOUT: |
a320e9fa PB |
3779 | case IORING_OP_TIMEOUT_REMOVE: |
3780 | case IORING_OP_ASYNC_CANCEL: | |
3781 | case IORING_OP_LINK_TIMEOUT: | |
9e3aa61a | 3782 | return 0; |
15b71abe | 3783 | case IORING_OP_OPENAT: |
eddc7ef5 | 3784 | case IORING_OP_STATX: |
15b71abe | 3785 | return fd != -1; |
09bb8394 | 3786 | default: |
d625c6ee | 3787 | if (io_req_op_valid(req->opcode)) |
9e3aa61a JA |
3788 | return 1; |
3789 | return -EINVAL; | |
09bb8394 JA |
3790 | } |
3791 | } | |
3792 | ||
65e19f54 JA |
3793 | static inline struct file *io_file_from_index(struct io_ring_ctx *ctx, |
3794 | int index) | |
3795 | { | |
3796 | struct fixed_file_table *table; | |
3797 | ||
05f3fb3c JA |
3798 | table = &ctx->file_data->table[index >> IORING_FILE_TABLE_SHIFT]; |
3799 | return table->files[index & IORING_FILE_TABLE_MASK];; | |
65e19f54 JA |
3800 | } |
3801 | ||
3529d8c2 JA |
3802 | static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req, |
3803 | const struct io_uring_sqe *sqe) | |
09bb8394 | 3804 | { |
a197f664 | 3805 | struct io_ring_ctx *ctx = req->ctx; |
09bb8394 | 3806 | unsigned flags; |
9e3aa61a | 3807 | int fd, ret; |
09bb8394 | 3808 | |
3529d8c2 JA |
3809 | flags = READ_ONCE(sqe->flags); |
3810 | fd = READ_ONCE(sqe->fd); | |
09bb8394 | 3811 | |
4fe2c963 | 3812 | if (flags & IOSQE_IO_DRAIN) |
de0617e4 | 3813 | req->flags |= REQ_F_IO_DRAIN; |
de0617e4 | 3814 | |
15b71abe | 3815 | ret = io_req_needs_file(req, fd); |
9e3aa61a JA |
3816 | if (ret <= 0) |
3817 | return ret; | |
09bb8394 JA |
3818 | |
3819 | if (flags & IOSQE_FIXED_FILE) { | |
05f3fb3c | 3820 | if (unlikely(!ctx->file_data || |
09bb8394 JA |
3821 | (unsigned) fd >= ctx->nr_user_files)) |
3822 | return -EBADF; | |
b7620121 | 3823 | fd = array_index_nospec(fd, ctx->nr_user_files); |
65e19f54 JA |
3824 | req->file = io_file_from_index(ctx, fd); |
3825 | if (!req->file) | |
08a45173 | 3826 | return -EBADF; |
09bb8394 | 3827 | req->flags |= REQ_F_FIXED_FILE; |
05f3fb3c | 3828 | percpu_ref_get(&ctx->file_data->refs); |
09bb8394 | 3829 | } else { |
cf6fd4bd | 3830 | if (req->needs_fixed_file) |
09bb8394 | 3831 | return -EBADF; |
c826bd7a | 3832 | trace_io_uring_file_get(ctx, fd); |
09bb8394 JA |
3833 | req->file = io_file_get(state, fd); |
3834 | if (unlikely(!req->file)) | |
3835 | return -EBADF; | |
3836 | } | |
3837 | ||
3838 | return 0; | |
3839 | } | |
3840 | ||
a197f664 | 3841 | static int io_grab_files(struct io_kiocb *req) |
fcb323cc JA |
3842 | { |
3843 | int ret = -EBADF; | |
a197f664 | 3844 | struct io_ring_ctx *ctx = req->ctx; |
fcb323cc | 3845 | |
b5dba59e JA |
3846 | if (!req->ring_file) |
3847 | return -EBADF; | |
3848 | ||
fcb323cc JA |
3849 | rcu_read_lock(); |
3850 | spin_lock_irq(&ctx->inflight_lock); | |
3851 | /* | |
3852 | * We use the f_ops->flush() handler to ensure that we can flush | |
3853 | * out work accessing these files if the fd is closed. Check if | |
3854 | * the fd has changed since we started down this path, and disallow | |
3855 | * this operation if it has. | |
3856 | */ | |
cf6fd4bd | 3857 | if (fcheck(req->ring_fd) == req->ring_file) { |
fcb323cc JA |
3858 | list_add(&req->inflight_entry, &ctx->inflight_list); |
3859 | req->flags |= REQ_F_INFLIGHT; | |
3860 | req->work.files = current->files; | |
3861 | ret = 0; | |
3862 | } | |
3863 | spin_unlock_irq(&ctx->inflight_lock); | |
3864 | rcu_read_unlock(); | |
3865 | ||
3866 | return ret; | |
3867 | } | |
3868 | ||
2665abfd | 3869 | static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer) |
2b188cc1 | 3870 | { |
ad8a48ac JA |
3871 | struct io_timeout_data *data = container_of(timer, |
3872 | struct io_timeout_data, timer); | |
3873 | struct io_kiocb *req = data->req; | |
2665abfd JA |
3874 | struct io_ring_ctx *ctx = req->ctx; |
3875 | struct io_kiocb *prev = NULL; | |
3876 | unsigned long flags; | |
2665abfd JA |
3877 | |
3878 | spin_lock_irqsave(&ctx->completion_lock, flags); | |
3879 | ||
3880 | /* | |
3881 | * We don't expect the list to be empty, that will only happen if we | |
3882 | * race with the completion of the linked work. | |
3883 | */ | |
4493233e PB |
3884 | if (!list_empty(&req->link_list)) { |
3885 | prev = list_entry(req->link_list.prev, struct io_kiocb, | |
3886 | link_list); | |
5d960724 | 3887 | if (refcount_inc_not_zero(&prev->refs)) { |
4493233e | 3888 | list_del_init(&req->link_list); |
5d960724 JA |
3889 | prev->flags &= ~REQ_F_LINK_TIMEOUT; |
3890 | } else | |
76a46e06 | 3891 | prev = NULL; |
2665abfd JA |
3892 | } |
3893 | ||
3894 | spin_unlock_irqrestore(&ctx->completion_lock, flags); | |
3895 | ||
3896 | if (prev) { | |
4e88d6e7 | 3897 | req_set_fail_links(prev); |
b0dd8a41 JA |
3898 | io_async_find_and_cancel(ctx, req, prev->user_data, NULL, |
3899 | -ETIME); | |
76a46e06 | 3900 | io_put_req(prev); |
47f46768 JA |
3901 | } else { |
3902 | io_cqring_add_event(req, -ETIME); | |
3903 | io_put_req(req); | |
2665abfd | 3904 | } |
2665abfd JA |
3905 | return HRTIMER_NORESTART; |
3906 | } | |
3907 | ||
ad8a48ac | 3908 | static void io_queue_linked_timeout(struct io_kiocb *req) |
2665abfd | 3909 | { |
76a46e06 | 3910 | struct io_ring_ctx *ctx = req->ctx; |
2665abfd | 3911 | |
76a46e06 JA |
3912 | /* |
3913 | * If the list is now empty, then our linked request finished before | |
3914 | * we got a chance to setup the timer | |
3915 | */ | |
3916 | spin_lock_irq(&ctx->completion_lock); | |
4493233e | 3917 | if (!list_empty(&req->link_list)) { |
2d28390a | 3918 | struct io_timeout_data *data = &req->io->timeout; |
94ae5e77 | 3919 | |
ad8a48ac JA |
3920 | data->timer.function = io_link_timeout_fn; |
3921 | hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), | |
3922 | data->mode); | |
2665abfd | 3923 | } |
76a46e06 | 3924 | spin_unlock_irq(&ctx->completion_lock); |
2665abfd | 3925 | |
2665abfd | 3926 | /* drop submission reference */ |
76a46e06 JA |
3927 | io_put_req(req); |
3928 | } | |
2665abfd | 3929 | |
ad8a48ac | 3930 | static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) |
2665abfd JA |
3931 | { |
3932 | struct io_kiocb *nxt; | |
3933 | ||
3934 | if (!(req->flags & REQ_F_LINK)) | |
3935 | return NULL; | |
3936 | ||
4493233e PB |
3937 | nxt = list_first_entry_or_null(&req->link_list, struct io_kiocb, |
3938 | link_list); | |
d625c6ee | 3939 | if (!nxt || nxt->opcode != IORING_OP_LINK_TIMEOUT) |
76a46e06 | 3940 | return NULL; |
2665abfd | 3941 | |
76a46e06 | 3942 | req->flags |= REQ_F_LINK_TIMEOUT; |
76a46e06 | 3943 | return nxt; |
2665abfd JA |
3944 | } |
3945 | ||
3529d8c2 | 3946 | static void __io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
2b188cc1 | 3947 | { |
4a0a7a18 | 3948 | struct io_kiocb *linked_timeout; |
f9bd67f6 | 3949 | struct io_kiocb *nxt = NULL; |
e0c5c576 | 3950 | int ret; |
2b188cc1 | 3951 | |
4a0a7a18 JA |
3952 | again: |
3953 | linked_timeout = io_prep_linked_timeout(req); | |
3954 | ||
3529d8c2 | 3955 | ret = io_issue_sqe(req, sqe, &nxt, true); |
491381ce JA |
3956 | |
3957 | /* | |
3958 | * We async punt it if the file wasn't marked NOWAIT, or if the file | |
3959 | * doesn't support non-blocking read/write attempts | |
3960 | */ | |
3961 | if (ret == -EAGAIN && (!(req->flags & REQ_F_NOWAIT) || | |
3962 | (req->flags & REQ_F_MUST_PUNT))) { | |
bbad27b2 PB |
3963 | if (req->work.flags & IO_WQ_WORK_NEEDS_FILES) { |
3964 | ret = io_grab_files(req); | |
3965 | if (ret) | |
3966 | goto err; | |
2b188cc1 | 3967 | } |
bbad27b2 PB |
3968 | |
3969 | /* | |
3970 | * Queued up for async execution, worker will release | |
3971 | * submit reference when the iocb is actually submitted. | |
3972 | */ | |
3973 | io_queue_async_work(req); | |
4a0a7a18 | 3974 | goto done_req; |
2b188cc1 | 3975 | } |
e65ef56d | 3976 | |
fcb323cc | 3977 | err: |
76a46e06 | 3978 | /* drop submission reference */ |
ec9c02ad | 3979 | io_put_req(req); |
e65ef56d | 3980 | |
f9bd67f6 | 3981 | if (linked_timeout) { |
76a46e06 | 3982 | if (!ret) |
f9bd67f6 | 3983 | io_queue_linked_timeout(linked_timeout); |
76a46e06 | 3984 | else |
f9bd67f6 | 3985 | io_put_req(linked_timeout); |
76a46e06 JA |
3986 | } |
3987 | ||
e65ef56d | 3988 | /* and drop final reference, if we failed */ |
9e645e11 | 3989 | if (ret) { |
78e19bbe | 3990 | io_cqring_add_event(req, ret); |
4e88d6e7 | 3991 | req_set_fail_links(req); |
e65ef56d | 3992 | io_put_req(req); |
9e645e11 | 3993 | } |
4a0a7a18 JA |
3994 | done_req: |
3995 | if (nxt) { | |
3996 | req = nxt; | |
3997 | nxt = NULL; | |
3998 | goto again; | |
3999 | } | |
2b188cc1 JA |
4000 | } |
4001 | ||
3529d8c2 | 4002 | static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe) |
4fe2c963 JL |
4003 | { |
4004 | int ret; | |
4005 | ||
1b4a51b6 PB |
4006 | if (unlikely(req->ctx->drain_next)) { |
4007 | req->flags |= REQ_F_IO_DRAIN; | |
4008 | req->ctx->drain_next = false; | |
4009 | } | |
4010 | req->ctx->drain_next = (req->flags & REQ_F_DRAIN_LINK); | |
4011 | ||
3529d8c2 | 4012 | ret = io_req_defer(req, sqe); |
4fe2c963 JL |
4013 | if (ret) { |
4014 | if (ret != -EIOCBQUEUED) { | |
78e19bbe | 4015 | io_cqring_add_event(req, ret); |
4e88d6e7 | 4016 | req_set_fail_links(req); |
78e19bbe | 4017 | io_double_put_req(req); |
4fe2c963 | 4018 | } |
ce35a47a JA |
4019 | } else if ((req->flags & REQ_F_FORCE_ASYNC) && |
4020 | !io_wq_current_is_worker()) { | |
4021 | /* | |
4022 | * Never try inline submit of IOSQE_ASYNC is set, go straight | |
4023 | * to async execution. | |
4024 | */ | |
4025 | req->work.flags |= IO_WQ_WORK_CONCURRENT; | |
4026 | io_queue_async_work(req); | |
4027 | } else { | |
3529d8c2 | 4028 | __io_queue_sqe(req, sqe); |
ce35a47a | 4029 | } |
4fe2c963 JL |
4030 | } |
4031 | ||
1b4a51b6 | 4032 | static inline void io_queue_link_head(struct io_kiocb *req) |
4fe2c963 | 4033 | { |
94ae5e77 | 4034 | if (unlikely(req->flags & REQ_F_FAIL_LINK)) { |
1b4a51b6 PB |
4035 | io_cqring_add_event(req, -ECANCELED); |
4036 | io_double_put_req(req); | |
4037 | } else | |
3529d8c2 | 4038 | io_queue_sqe(req, NULL); |
4fe2c963 JL |
4039 | } |
4040 | ||
4e88d6e7 | 4041 | #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \ |
ce35a47a | 4042 | IOSQE_IO_HARDLINK | IOSQE_ASYNC) |
9e645e11 | 4043 | |
3529d8c2 JA |
4044 | static bool io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, |
4045 | struct io_submit_state *state, struct io_kiocb **link) | |
9e645e11 | 4046 | { |
a197f664 | 4047 | struct io_ring_ctx *ctx = req->ctx; |
32fe525b | 4048 | unsigned int sqe_flags; |
9e645e11 JA |
4049 | int ret; |
4050 | ||
32fe525b PB |
4051 | sqe_flags = READ_ONCE(sqe->flags); |
4052 | ||
9e645e11 | 4053 | /* enforce forwards compatibility on users */ |
32fe525b | 4054 | if (unlikely(sqe_flags & ~SQE_VALID_FLAGS)) { |
9e645e11 | 4055 | ret = -EINVAL; |
196be95c | 4056 | goto err_req; |
9e645e11 | 4057 | } |
32fe525b | 4058 | if (sqe_flags & IOSQE_ASYNC) |
ce35a47a | 4059 | req->flags |= REQ_F_FORCE_ASYNC; |
9e645e11 | 4060 | |
3529d8c2 | 4061 | ret = io_req_set_file(state, req, sqe); |
9e645e11 JA |
4062 | if (unlikely(ret)) { |
4063 | err_req: | |
78e19bbe JA |
4064 | io_cqring_add_event(req, ret); |
4065 | io_double_put_req(req); | |
2e6e1fde | 4066 | return false; |
9e645e11 JA |
4067 | } |
4068 | ||
9e645e11 JA |
4069 | /* |
4070 | * If we already have a head request, queue this one for async | |
4071 | * submittal once the head completes. If we don't have a head but | |
4072 | * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be | |
4073 | * submitted sync once the chain is complete. If none of those | |
4074 | * conditions are true (normal request), then just queue it. | |
4075 | */ | |
4076 | if (*link) { | |
9d76377f | 4077 | struct io_kiocb *head = *link; |
9e645e11 | 4078 | |
32fe525b | 4079 | if (sqe_flags & IOSQE_IO_DRAIN) |
9d76377f | 4080 | head->flags |= REQ_F_DRAIN_LINK | REQ_F_IO_DRAIN; |
1b4a51b6 | 4081 | |
32fe525b | 4082 | if (sqe_flags & IOSQE_IO_HARDLINK) |
4e88d6e7 JA |
4083 | req->flags |= REQ_F_HARDLINK; |
4084 | ||
b7bb4f7d | 4085 | if (io_alloc_async_ctx(req)) { |
9e645e11 JA |
4086 | ret = -EAGAIN; |
4087 | goto err_req; | |
4088 | } | |
4089 | ||
3529d8c2 | 4090 | ret = io_req_defer_prep(req, sqe); |
2d28390a | 4091 | if (ret) { |
4e88d6e7 | 4092 | /* fail even hard links since we don't submit */ |
9d76377f | 4093 | head->flags |= REQ_F_FAIL_LINK; |
f67676d1 | 4094 | goto err_req; |
2d28390a | 4095 | } |
9d76377f PB |
4096 | trace_io_uring_link(ctx, req, head); |
4097 | list_add_tail(&req->link_list, &head->link_list); | |
32fe525b PB |
4098 | |
4099 | /* last request of a link, enqueue the link */ | |
4100 | if (!(sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK))) { | |
4101 | io_queue_link_head(head); | |
4102 | *link = NULL; | |
4103 | } | |
4104 | } else if (sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) { | |
9e645e11 | 4105 | req->flags |= REQ_F_LINK; |
32fe525b | 4106 | if (sqe_flags & IOSQE_IO_HARDLINK) |
4e88d6e7 | 4107 | req->flags |= REQ_F_HARDLINK; |
9e645e11 | 4108 | |
9e645e11 | 4109 | INIT_LIST_HEAD(&req->link_list); |
3529d8c2 JA |
4110 | ret = io_req_defer_prep(req, sqe); |
4111 | if (ret) | |
4112 | req->flags |= REQ_F_FAIL_LINK; | |
9e645e11 JA |
4113 | *link = req; |
4114 | } else { | |
3529d8c2 | 4115 | io_queue_sqe(req, sqe); |
9e645e11 | 4116 | } |
2e6e1fde PB |
4117 | |
4118 | return true; | |
9e645e11 JA |
4119 | } |
4120 | ||
9a56a232 JA |
4121 | /* |
4122 | * Batched submission is done, ensure local IO is flushed out. | |
4123 | */ | |
4124 | static void io_submit_state_end(struct io_submit_state *state) | |
4125 | { | |
4126 | blk_finish_plug(&state->plug); | |
3d6770fb | 4127 | io_file_put(state); |
2579f913 JA |
4128 | if (state->free_reqs) |
4129 | kmem_cache_free_bulk(req_cachep, state->free_reqs, | |
4130 | &state->reqs[state->cur_req]); | |
9a56a232 JA |
4131 | } |
4132 | ||
4133 | /* | |
4134 | * Start submission side cache. | |
4135 | */ | |
4136 | static void io_submit_state_start(struct io_submit_state *state, | |
22efde59 | 4137 | unsigned int max_ios) |
9a56a232 JA |
4138 | { |
4139 | blk_start_plug(&state->plug); | |
2579f913 | 4140 | state->free_reqs = 0; |
9a56a232 JA |
4141 | state->file = NULL; |
4142 | state->ios_left = max_ios; | |
4143 | } | |
4144 | ||
2b188cc1 JA |
4145 | static void io_commit_sqring(struct io_ring_ctx *ctx) |
4146 | { | |
75b28aff | 4147 | struct io_rings *rings = ctx->rings; |
2b188cc1 | 4148 | |
75b28aff | 4149 | if (ctx->cached_sq_head != READ_ONCE(rings->sq.head)) { |
2b188cc1 JA |
4150 | /* |
4151 | * Ensure any loads from the SQEs are done at this point, | |
4152 | * since once we write the new head, the application could | |
4153 | * write new data to them. | |
4154 | */ | |
75b28aff | 4155 | smp_store_release(&rings->sq.head, ctx->cached_sq_head); |
2b188cc1 JA |
4156 | } |
4157 | } | |
4158 | ||
2b188cc1 | 4159 | /* |
3529d8c2 | 4160 | * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory |
2b188cc1 JA |
4161 | * that is mapped by userspace. This means that care needs to be taken to |
4162 | * ensure that reads are stable, as we cannot rely on userspace always | |
4163 | * being a good citizen. If members of the sqe are validated and then later | |
4164 | * used, it's important that those reads are done through READ_ONCE() to | |
4165 | * prevent a re-load down the line. | |
4166 | */ | |
3529d8c2 JA |
4167 | static bool io_get_sqring(struct io_ring_ctx *ctx, struct io_kiocb *req, |
4168 | const struct io_uring_sqe **sqe_ptr) | |
2b188cc1 | 4169 | { |
75b28aff HV |
4170 | struct io_rings *rings = ctx->rings; |
4171 | u32 *sq_array = ctx->sq_array; | |
2b188cc1 JA |
4172 | unsigned head; |
4173 | ||
4174 | /* | |
4175 | * The cached sq head (or cq tail) serves two purposes: | |
4176 | * | |
4177 | * 1) allows us to batch the cost of updating the user visible | |
4178 | * head updates. | |
4179 | * 2) allows the kernel side to track the head on its own, even | |
4180 | * though the application is the one updating it. | |
4181 | */ | |
4182 | head = ctx->cached_sq_head; | |
e523a29c | 4183 | /* make sure SQ entry isn't read before tail */ |
9835d6fa | 4184 | if (unlikely(head == smp_load_acquire(&rings->sq.tail))) |
2b188cc1 JA |
4185 | return false; |
4186 | ||
75b28aff | 4187 | head = READ_ONCE(sq_array[head & ctx->sq_mask]); |
9835d6fa | 4188 | if (likely(head < ctx->sq_entries)) { |
cf6fd4bd PB |
4189 | /* |
4190 | * All io need record the previous position, if LINK vs DARIN, | |
4191 | * it can be used to mark the position of the first IO in the | |
4192 | * link list. | |
4193 | */ | |
4194 | req->sequence = ctx->cached_sq_head; | |
3529d8c2 JA |
4195 | *sqe_ptr = &ctx->sq_sqes[head]; |
4196 | req->opcode = READ_ONCE((*sqe_ptr)->opcode); | |
4197 | req->user_data = READ_ONCE((*sqe_ptr)->user_data); | |
2b188cc1 JA |
4198 | ctx->cached_sq_head++; |
4199 | return true; | |
4200 | } | |
4201 | ||
4202 | /* drop invalid entries */ | |
4203 | ctx->cached_sq_head++; | |
498ccd9e JA |
4204 | ctx->cached_sq_dropped++; |
4205 | WRITE_ONCE(rings->sq_dropped, ctx->cached_sq_dropped); | |
2b188cc1 JA |
4206 | return false; |
4207 | } | |
4208 | ||
fb5ccc98 | 4209 | static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr, |
ae9428ca PB |
4210 | struct file *ring_file, int ring_fd, |
4211 | struct mm_struct **mm, bool async) | |
6c271ce2 JA |
4212 | { |
4213 | struct io_submit_state state, *statep = NULL; | |
9e645e11 | 4214 | struct io_kiocb *link = NULL; |
9e645e11 | 4215 | int i, submitted = 0; |
95a1b3ff | 4216 | bool mm_fault = false; |
6c271ce2 | 4217 | |
c4a2ed72 JA |
4218 | /* if we have a backlog and couldn't flush it all, return BUSY */ |
4219 | if (!list_empty(&ctx->cq_overflow_list) && | |
4220 | !io_cqring_overflow_flush(ctx, false)) | |
1d7bb1d5 | 4221 | return -EBUSY; |
6c271ce2 JA |
4222 | |
4223 | if (nr > IO_PLUG_THRESHOLD) { | |
22efde59 | 4224 | io_submit_state_start(&state, nr); |
6c271ce2 JA |
4225 | statep = &state; |
4226 | } | |
4227 | ||
4228 | for (i = 0; i < nr; i++) { | |
3529d8c2 | 4229 | const struct io_uring_sqe *sqe; |
196be95c | 4230 | struct io_kiocb *req; |
fb5ccc98 | 4231 | |
196be95c PB |
4232 | req = io_get_req(ctx, statep); |
4233 | if (unlikely(!req)) { | |
4234 | if (!submitted) | |
4235 | submitted = -EAGAIN; | |
fb5ccc98 | 4236 | break; |
196be95c | 4237 | } |
3529d8c2 | 4238 | if (!io_get_sqring(ctx, req, &sqe)) { |
196be95c PB |
4239 | __io_free_req(req); |
4240 | break; | |
4241 | } | |
fb5ccc98 | 4242 | |
d625c6ee | 4243 | if (io_req_needs_user(req) && !*mm) { |
95a1b3ff PB |
4244 | mm_fault = mm_fault || !mmget_not_zero(ctx->sqo_mm); |
4245 | if (!mm_fault) { | |
4246 | use_mm(ctx->sqo_mm); | |
4247 | *mm = ctx->sqo_mm; | |
4248 | } | |
9e645e11 | 4249 | } |
9e645e11 | 4250 | |
2e6e1fde | 4251 | submitted++; |
cf6fd4bd PB |
4252 | req->ring_file = ring_file; |
4253 | req->ring_fd = ring_fd; | |
4254 | req->has_user = *mm != NULL; | |
4255 | req->in_async = async; | |
4256 | req->needs_fixed_file = async; | |
d625c6ee | 4257 | trace_io_uring_submit_sqe(ctx, req->user_data, true, async); |
3529d8c2 | 4258 | if (!io_submit_sqe(req, sqe, statep, &link)) |
2e6e1fde | 4259 | break; |
6c271ce2 JA |
4260 | } |
4261 | ||
9e645e11 | 4262 | if (link) |
1b4a51b6 | 4263 | io_queue_link_head(link); |
6c271ce2 JA |
4264 | if (statep) |
4265 | io_submit_state_end(&state); | |
4266 | ||
ae9428ca PB |
4267 | /* Commit SQ ring head once we've consumed and submitted all SQEs */ |
4268 | io_commit_sqring(ctx); | |
4269 | ||
6c271ce2 JA |
4270 | return submitted; |
4271 | } | |
4272 | ||
4273 | static int io_sq_thread(void *data) | |
4274 | { | |
6c271ce2 JA |
4275 | struct io_ring_ctx *ctx = data; |
4276 | struct mm_struct *cur_mm = NULL; | |
181e448d | 4277 | const struct cred *old_cred; |
6c271ce2 JA |
4278 | mm_segment_t old_fs; |
4279 | DEFINE_WAIT(wait); | |
4280 | unsigned inflight; | |
4281 | unsigned long timeout; | |
c1edbf5f | 4282 | int ret; |
6c271ce2 | 4283 | |
206aefde | 4284 | complete(&ctx->completions[1]); |
a4c0b3de | 4285 | |
6c271ce2 JA |
4286 | old_fs = get_fs(); |
4287 | set_fs(USER_DS); | |
181e448d | 4288 | old_cred = override_creds(ctx->creds); |
6c271ce2 | 4289 | |
c1edbf5f | 4290 | ret = timeout = inflight = 0; |
2bbcd6d3 | 4291 | while (!kthread_should_park()) { |
fb5ccc98 | 4292 | unsigned int to_submit; |
6c271ce2 JA |
4293 | |
4294 | if (inflight) { | |
4295 | unsigned nr_events = 0; | |
4296 | ||
4297 | if (ctx->flags & IORING_SETUP_IOPOLL) { | |
2b2ed975 JA |
4298 | /* |
4299 | * inflight is the count of the maximum possible | |
4300 | * entries we submitted, but it can be smaller | |
4301 | * if we dropped some of them. If we don't have | |
4302 | * poll entries available, then we know that we | |
4303 | * have nothing left to poll for. Reset the | |
4304 | * inflight count to zero in that case. | |
4305 | */ | |
4306 | mutex_lock(&ctx->uring_lock); | |
4307 | if (!list_empty(&ctx->poll_list)) | |
4308 | __io_iopoll_check(ctx, &nr_events, 0); | |
4309 | else | |
4310 | inflight = 0; | |
4311 | mutex_unlock(&ctx->uring_lock); | |
6c271ce2 JA |
4312 | } else { |
4313 | /* | |
4314 | * Normal IO, just pretend everything completed. | |
4315 | * We don't have to poll completions for that. | |
4316 | */ | |
4317 | nr_events = inflight; | |
4318 | } | |
4319 | ||
4320 | inflight -= nr_events; | |
4321 | if (!inflight) | |
4322 | timeout = jiffies + ctx->sq_thread_idle; | |
4323 | } | |
4324 | ||
fb5ccc98 | 4325 | to_submit = io_sqring_entries(ctx); |
c1edbf5f JA |
4326 | |
4327 | /* | |
4328 | * If submit got -EBUSY, flag us as needing the application | |
4329 | * to enter the kernel to reap and flush events. | |
4330 | */ | |
4331 | if (!to_submit || ret == -EBUSY) { | |
6c271ce2 JA |
4332 | /* |
4333 | * We're polling. If we're within the defined idle | |
4334 | * period, then let us spin without work before going | |
c1edbf5f JA |
4335 | * to sleep. The exception is if we got EBUSY doing |
4336 | * more IO, we should wait for the application to | |
4337 | * reap events and wake us up. | |
6c271ce2 | 4338 | */ |
c1edbf5f JA |
4339 | if (inflight || |
4340 | (!time_after(jiffies, timeout) && ret != -EBUSY)) { | |
9831a90c | 4341 | cond_resched(); |
6c271ce2 JA |
4342 | continue; |
4343 | } | |
4344 | ||
4345 | /* | |
4346 | * Drop cur_mm before scheduling, we can't hold it for | |
4347 | * long periods (or over schedule()). Do this before | |
4348 | * adding ourselves to the waitqueue, as the unuse/drop | |
4349 | * may sleep. | |
4350 | */ | |
4351 | if (cur_mm) { | |
4352 | unuse_mm(cur_mm); | |
4353 | mmput(cur_mm); | |
4354 | cur_mm = NULL; | |
4355 | } | |
4356 | ||
4357 | prepare_to_wait(&ctx->sqo_wait, &wait, | |
4358 | TASK_INTERRUPTIBLE); | |
4359 | ||
4360 | /* Tell userspace we may need a wakeup call */ | |
75b28aff | 4361 | ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP; |
0d7bae69 SB |
4362 | /* make sure to read SQ tail after writing flags */ |
4363 | smp_mb(); | |
6c271ce2 | 4364 | |
fb5ccc98 | 4365 | to_submit = io_sqring_entries(ctx); |
c1edbf5f | 4366 | if (!to_submit || ret == -EBUSY) { |
2bbcd6d3 | 4367 | if (kthread_should_park()) { |
6c271ce2 JA |
4368 | finish_wait(&ctx->sqo_wait, &wait); |
4369 | break; | |
4370 | } | |
4371 | if (signal_pending(current)) | |
4372 | flush_signals(current); | |
4373 | schedule(); | |
4374 | finish_wait(&ctx->sqo_wait, &wait); | |
4375 | ||
75b28aff | 4376 | ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP; |
6c271ce2 JA |
4377 | continue; |
4378 | } | |
4379 | finish_wait(&ctx->sqo_wait, &wait); | |
4380 | ||
75b28aff | 4381 | ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP; |
6c271ce2 JA |
4382 | } |
4383 | ||
fb5ccc98 | 4384 | to_submit = min(to_submit, ctx->sq_entries); |
8a4955ff | 4385 | mutex_lock(&ctx->uring_lock); |
1d7bb1d5 | 4386 | ret = io_submit_sqes(ctx, to_submit, NULL, -1, &cur_mm, true); |
8a4955ff | 4387 | mutex_unlock(&ctx->uring_lock); |
1d7bb1d5 JA |
4388 | if (ret > 0) |
4389 | inflight += ret; | |
6c271ce2 JA |
4390 | } |
4391 | ||
4392 | set_fs(old_fs); | |
4393 | if (cur_mm) { | |
4394 | unuse_mm(cur_mm); | |
4395 | mmput(cur_mm); | |
4396 | } | |
181e448d | 4397 | revert_creds(old_cred); |
06058632 | 4398 | |
2bbcd6d3 | 4399 | kthread_parkme(); |
06058632 | 4400 | |
6c271ce2 JA |
4401 | return 0; |
4402 | } | |
4403 | ||
bda52162 JA |
4404 | struct io_wait_queue { |
4405 | struct wait_queue_entry wq; | |
4406 | struct io_ring_ctx *ctx; | |
4407 | unsigned to_wait; | |
4408 | unsigned nr_timeouts; | |
4409 | }; | |
4410 | ||
1d7bb1d5 | 4411 | static inline bool io_should_wake(struct io_wait_queue *iowq, bool noflush) |
bda52162 JA |
4412 | { |
4413 | struct io_ring_ctx *ctx = iowq->ctx; | |
4414 | ||
4415 | /* | |
d195a66e | 4416 | * Wake up if we have enough events, or if a timeout occurred since we |
bda52162 JA |
4417 | * started waiting. For timeouts, we always want to return to userspace, |
4418 | * regardless of event count. | |
4419 | */ | |
1d7bb1d5 | 4420 | return io_cqring_events(ctx, noflush) >= iowq->to_wait || |
bda52162 JA |
4421 | atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts; |
4422 | } | |
4423 | ||
4424 | static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, | |
4425 | int wake_flags, void *key) | |
4426 | { | |
4427 | struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue, | |
4428 | wq); | |
4429 | ||
1d7bb1d5 JA |
4430 | /* use noflush == true, as we can't safely rely on locking context */ |
4431 | if (!io_should_wake(iowq, true)) | |
bda52162 JA |
4432 | return -1; |
4433 | ||
4434 | return autoremove_wake_function(curr, mode, wake_flags, key); | |
4435 | } | |
4436 | ||
2b188cc1 JA |
4437 | /* |
4438 | * Wait until events become available, if we don't already have some. The | |
4439 | * application must reap them itself, as they reside on the shared cq ring. | |
4440 | */ | |
4441 | static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, | |
4442 | const sigset_t __user *sig, size_t sigsz) | |
4443 | { | |
bda52162 JA |
4444 | struct io_wait_queue iowq = { |
4445 | .wq = { | |
4446 | .private = current, | |
4447 | .func = io_wake_function, | |
4448 | .entry = LIST_HEAD_INIT(iowq.wq.entry), | |
4449 | }, | |
4450 | .ctx = ctx, | |
4451 | .to_wait = min_events, | |
4452 | }; | |
75b28aff | 4453 | struct io_rings *rings = ctx->rings; |
e9ffa5c2 | 4454 | int ret = 0; |
2b188cc1 | 4455 | |
1d7bb1d5 | 4456 | if (io_cqring_events(ctx, false) >= min_events) |
2b188cc1 JA |
4457 | return 0; |
4458 | ||
4459 | if (sig) { | |
9e75ad5d AB |
4460 | #ifdef CONFIG_COMPAT |
4461 | if (in_compat_syscall()) | |
4462 | ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig, | |
b772434b | 4463 | sigsz); |
9e75ad5d AB |
4464 | else |
4465 | #endif | |
b772434b | 4466 | ret = set_user_sigmask(sig, sigsz); |
9e75ad5d | 4467 | |
2b188cc1 JA |
4468 | if (ret) |
4469 | return ret; | |
4470 | } | |
4471 | ||
bda52162 | 4472 | iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts); |
c826bd7a | 4473 | trace_io_uring_cqring_wait(ctx, min_events); |
bda52162 JA |
4474 | do { |
4475 | prepare_to_wait_exclusive(&ctx->wait, &iowq.wq, | |
4476 | TASK_INTERRUPTIBLE); | |
1d7bb1d5 | 4477 | if (io_should_wake(&iowq, false)) |
bda52162 JA |
4478 | break; |
4479 | schedule(); | |
4480 | if (signal_pending(current)) { | |
e9ffa5c2 | 4481 | ret = -EINTR; |
bda52162 JA |
4482 | break; |
4483 | } | |
4484 | } while (1); | |
4485 | finish_wait(&ctx->wait, &iowq.wq); | |
4486 | ||
e9ffa5c2 | 4487 | restore_saved_sigmask_unless(ret == -EINTR); |
2b188cc1 | 4488 | |
75b28aff | 4489 | return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0; |
2b188cc1 JA |
4490 | } |
4491 | ||
6b06314c JA |
4492 | static void __io_sqe_files_unregister(struct io_ring_ctx *ctx) |
4493 | { | |
4494 | #if defined(CONFIG_UNIX) | |
4495 | if (ctx->ring_sock) { | |
4496 | struct sock *sock = ctx->ring_sock->sk; | |
4497 | struct sk_buff *skb; | |
4498 | ||
4499 | while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL) | |
4500 | kfree_skb(skb); | |
4501 | } | |
4502 | #else | |
4503 | int i; | |
4504 | ||
65e19f54 JA |
4505 | for (i = 0; i < ctx->nr_user_files; i++) { |
4506 | struct file *file; | |
4507 | ||
4508 | file = io_file_from_index(ctx, i); | |
4509 | if (file) | |
4510 | fput(file); | |
4511 | } | |
6b06314c JA |
4512 | #endif |
4513 | } | |
4514 | ||
05f3fb3c JA |
4515 | static void io_file_ref_kill(struct percpu_ref *ref) |
4516 | { | |
4517 | struct fixed_file_data *data; | |
4518 | ||
4519 | data = container_of(ref, struct fixed_file_data, refs); | |
4520 | complete(&data->done); | |
4521 | } | |
4522 | ||
6b06314c JA |
4523 | static int io_sqe_files_unregister(struct io_ring_ctx *ctx) |
4524 | { | |
05f3fb3c | 4525 | struct fixed_file_data *data = ctx->file_data; |
65e19f54 JA |
4526 | unsigned nr_tables, i; |
4527 | ||
05f3fb3c | 4528 | if (!data) |
6b06314c JA |
4529 | return -ENXIO; |
4530 | ||
05f3fb3c JA |
4531 | /* protect against inflight atomic switch, which drops the ref */ |
4532 | flush_work(&data->ref_work); | |
4533 | percpu_ref_get(&data->refs); | |
4534 | percpu_ref_kill_and_confirm(&data->refs, io_file_ref_kill); | |
4535 | wait_for_completion(&data->done); | |
4536 | percpu_ref_put(&data->refs); | |
4537 | percpu_ref_exit(&data->refs); | |
4538 | ||
6b06314c | 4539 | __io_sqe_files_unregister(ctx); |
65e19f54 JA |
4540 | nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE); |
4541 | for (i = 0; i < nr_tables; i++) | |
05f3fb3c JA |
4542 | kfree(data->table[i].files); |
4543 | kfree(data->table); | |
4544 | kfree(data); | |
4545 | ctx->file_data = NULL; | |
6b06314c JA |
4546 | ctx->nr_user_files = 0; |
4547 | return 0; | |
4548 | } | |
4549 | ||
6c271ce2 JA |
4550 | static void io_sq_thread_stop(struct io_ring_ctx *ctx) |
4551 | { | |
4552 | if (ctx->sqo_thread) { | |
206aefde | 4553 | wait_for_completion(&ctx->completions[1]); |
2bbcd6d3 RP |
4554 | /* |
4555 | * The park is a bit of a work-around, without it we get | |
4556 | * warning spews on shutdown with SQPOLL set and affinity | |
4557 | * set to a single CPU. | |
4558 | */ | |
06058632 | 4559 | kthread_park(ctx->sqo_thread); |
6c271ce2 JA |
4560 | kthread_stop(ctx->sqo_thread); |
4561 | ctx->sqo_thread = NULL; | |
4562 | } | |
4563 | } | |
4564 | ||
6b06314c JA |
4565 | static void io_finish_async(struct io_ring_ctx *ctx) |
4566 | { | |
6c271ce2 JA |
4567 | io_sq_thread_stop(ctx); |
4568 | ||
561fb04a JA |
4569 | if (ctx->io_wq) { |
4570 | io_wq_destroy(ctx->io_wq); | |
4571 | ctx->io_wq = NULL; | |
6b06314c JA |
4572 | } |
4573 | } | |
4574 | ||
4575 | #if defined(CONFIG_UNIX) | |
6b06314c JA |
4576 | /* |
4577 | * Ensure the UNIX gc is aware of our file set, so we are certain that | |
4578 | * the io_uring can be safely unregistered on process exit, even if we have | |
4579 | * loops in the file referencing. | |
4580 | */ | |
4581 | static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset) | |
4582 | { | |
4583 | struct sock *sk = ctx->ring_sock->sk; | |
4584 | struct scm_fp_list *fpl; | |
4585 | struct sk_buff *skb; | |
08a45173 | 4586 | int i, nr_files; |
6b06314c JA |
4587 | |
4588 | if (!capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN)) { | |
4589 | unsigned long inflight = ctx->user->unix_inflight + nr; | |
4590 | ||
4591 | if (inflight > task_rlimit(current, RLIMIT_NOFILE)) | |
4592 | return -EMFILE; | |
4593 | } | |
4594 | ||
4595 | fpl = kzalloc(sizeof(*fpl), GFP_KERNEL); | |
4596 | if (!fpl) | |
4597 | return -ENOMEM; | |
4598 | ||
4599 | skb = alloc_skb(0, GFP_KERNEL); | |
4600 | if (!skb) { | |
4601 | kfree(fpl); | |
4602 | return -ENOMEM; | |
4603 | } | |
4604 | ||
4605 | skb->sk = sk; | |
6b06314c | 4606 | |
08a45173 | 4607 | nr_files = 0; |
6b06314c JA |
4608 | fpl->user = get_uid(ctx->user); |
4609 | for (i = 0; i < nr; i++) { | |
65e19f54 JA |
4610 | struct file *file = io_file_from_index(ctx, i + offset); |
4611 | ||
4612 | if (!file) | |
08a45173 | 4613 | continue; |
65e19f54 | 4614 | fpl->fp[nr_files] = get_file(file); |
08a45173 JA |
4615 | unix_inflight(fpl->user, fpl->fp[nr_files]); |
4616 | nr_files++; | |
6b06314c JA |
4617 | } |
4618 | ||
08a45173 JA |
4619 | if (nr_files) { |
4620 | fpl->max = SCM_MAX_FD; | |
4621 | fpl->count = nr_files; | |
4622 | UNIXCB(skb).fp = fpl; | |
05f3fb3c | 4623 | skb->destructor = unix_destruct_scm; |
08a45173 JA |
4624 | refcount_add(skb->truesize, &sk->sk_wmem_alloc); |
4625 | skb_queue_head(&sk->sk_receive_queue, skb); | |
6b06314c | 4626 | |
08a45173 JA |
4627 | for (i = 0; i < nr_files; i++) |
4628 | fput(fpl->fp[i]); | |
4629 | } else { | |
4630 | kfree_skb(skb); | |
4631 | kfree(fpl); | |
4632 | } | |
6b06314c JA |
4633 | |
4634 | return 0; | |
4635 | } | |
4636 | ||
4637 | /* | |
4638 | * If UNIX sockets are enabled, fd passing can cause a reference cycle which | |
4639 | * causes regular reference counting to break down. We rely on the UNIX | |
4640 | * garbage collection to take care of this problem for us. | |
4641 | */ | |
4642 | static int io_sqe_files_scm(struct io_ring_ctx *ctx) | |
4643 | { | |
4644 | unsigned left, total; | |
4645 | int ret = 0; | |
4646 | ||
4647 | total = 0; | |
4648 | left = ctx->nr_user_files; | |
4649 | while (left) { | |
4650 | unsigned this_files = min_t(unsigned, left, SCM_MAX_FD); | |
6b06314c JA |
4651 | |
4652 | ret = __io_sqe_files_scm(ctx, this_files, total); | |
4653 | if (ret) | |
4654 | break; | |
4655 | left -= this_files; | |
4656 | total += this_files; | |
4657 | } | |
4658 | ||
4659 | if (!ret) | |
4660 | return 0; | |
4661 | ||
4662 | while (total < ctx->nr_user_files) { | |
65e19f54 JA |
4663 | struct file *file = io_file_from_index(ctx, total); |
4664 | ||
4665 | if (file) | |
4666 | fput(file); | |
6b06314c JA |
4667 | total++; |
4668 | } | |
4669 | ||
4670 | return ret; | |
4671 | } | |
4672 | #else | |
4673 | static int io_sqe_files_scm(struct io_ring_ctx *ctx) | |
4674 | { | |
4675 | return 0; | |
4676 | } | |
4677 | #endif | |
4678 | ||
65e19f54 JA |
4679 | static int io_sqe_alloc_file_tables(struct io_ring_ctx *ctx, unsigned nr_tables, |
4680 | unsigned nr_files) | |
4681 | { | |
4682 | int i; | |
4683 | ||
4684 | for (i = 0; i < nr_tables; i++) { | |
05f3fb3c | 4685 | struct fixed_file_table *table = &ctx->file_data->table[i]; |
65e19f54 JA |
4686 | unsigned this_files; |
4687 | ||
4688 | this_files = min(nr_files, IORING_MAX_FILES_TABLE); | |
4689 | table->files = kcalloc(this_files, sizeof(struct file *), | |
4690 | GFP_KERNEL); | |
4691 | if (!table->files) | |
4692 | break; | |
4693 | nr_files -= this_files; | |
4694 | } | |
4695 | ||
4696 | if (i == nr_tables) | |
4697 | return 0; | |
4698 | ||
4699 | for (i = 0; i < nr_tables; i++) { | |
05f3fb3c | 4700 | struct fixed_file_table *table = &ctx->file_data->table[i]; |
65e19f54 JA |
4701 | kfree(table->files); |
4702 | } | |
4703 | return 1; | |
4704 | } | |
4705 | ||
05f3fb3c JA |
4706 | static void io_ring_file_put(struct io_ring_ctx *ctx, struct file *file) |
4707 | { | |
4708 | #if defined(CONFIG_UNIX) | |
4709 | struct sock *sock = ctx->ring_sock->sk; | |
4710 | struct sk_buff_head list, *head = &sock->sk_receive_queue; | |
4711 | struct sk_buff *skb; | |
4712 | int i; | |
4713 | ||
4714 | __skb_queue_head_init(&list); | |
4715 | ||
4716 | /* | |
4717 | * Find the skb that holds this file in its SCM_RIGHTS. When found, | |
4718 | * remove this entry and rearrange the file array. | |
4719 | */ | |
4720 | skb = skb_dequeue(head); | |
4721 | while (skb) { | |
4722 | struct scm_fp_list *fp; | |
4723 | ||
4724 | fp = UNIXCB(skb).fp; | |
4725 | for (i = 0; i < fp->count; i++) { | |
4726 | int left; | |
4727 | ||
4728 | if (fp->fp[i] != file) | |
4729 | continue; | |
4730 | ||
4731 | unix_notinflight(fp->user, fp->fp[i]); | |
4732 | left = fp->count - 1 - i; | |
4733 | if (left) { | |
4734 | memmove(&fp->fp[i], &fp->fp[i + 1], | |
4735 | left * sizeof(struct file *)); | |
4736 | } | |
4737 | fp->count--; | |
4738 | if (!fp->count) { | |
4739 | kfree_skb(skb); | |
4740 | skb = NULL; | |
4741 | } else { | |
4742 | __skb_queue_tail(&list, skb); | |
4743 | } | |
4744 | fput(file); | |
4745 | file = NULL; | |
4746 | break; | |
4747 | } | |
4748 | ||
4749 | if (!file) | |
4750 | break; | |
4751 | ||
4752 | __skb_queue_tail(&list, skb); | |
4753 | ||
4754 | skb = skb_dequeue(head); | |
4755 | } | |
4756 | ||
4757 | if (skb_peek(&list)) { | |
4758 | spin_lock_irq(&head->lock); | |
4759 | while ((skb = __skb_dequeue(&list)) != NULL) | |
4760 | __skb_queue_tail(head, skb); | |
4761 | spin_unlock_irq(&head->lock); | |
4762 | } | |
4763 | #else | |
4764 | fput(file); | |
4765 | #endif | |
4766 | } | |
4767 | ||
4768 | struct io_file_put { | |
4769 | struct llist_node llist; | |
4770 | struct file *file; | |
4771 | struct completion *done; | |
4772 | }; | |
4773 | ||
4774 | static void io_ring_file_ref_switch(struct work_struct *work) | |
4775 | { | |
4776 | struct io_file_put *pfile, *tmp; | |
4777 | struct fixed_file_data *data; | |
4778 | struct llist_node *node; | |
4779 | ||
4780 | data = container_of(work, struct fixed_file_data, ref_work); | |
4781 | ||
4782 | while ((node = llist_del_all(&data->put_llist)) != NULL) { | |
4783 | llist_for_each_entry_safe(pfile, tmp, node, llist) { | |
4784 | io_ring_file_put(data->ctx, pfile->file); | |
4785 | if (pfile->done) | |
4786 | complete(pfile->done); | |
4787 | else | |
4788 | kfree(pfile); | |
4789 | } | |
4790 | } | |
4791 | ||
4792 | percpu_ref_get(&data->refs); | |
4793 | percpu_ref_switch_to_percpu(&data->refs); | |
4794 | } | |
4795 | ||
4796 | static void io_file_data_ref_zero(struct percpu_ref *ref) | |
4797 | { | |
4798 | struct fixed_file_data *data; | |
4799 | ||
4800 | data = container_of(ref, struct fixed_file_data, refs); | |
4801 | ||
4802 | /* we can't safely switch from inside this context, punt to wq */ | |
4803 | queue_work(system_wq, &data->ref_work); | |
4804 | } | |
4805 | ||
6b06314c JA |
4806 | static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, |
4807 | unsigned nr_args) | |
4808 | { | |
4809 | __s32 __user *fds = (__s32 __user *) arg; | |
65e19f54 | 4810 | unsigned nr_tables; |
05f3fb3c | 4811 | struct file *file; |
6b06314c JA |
4812 | int fd, ret = 0; |
4813 | unsigned i; | |
4814 | ||
05f3fb3c | 4815 | if (ctx->file_data) |
6b06314c JA |
4816 | return -EBUSY; |
4817 | if (!nr_args) | |
4818 | return -EINVAL; | |
4819 | if (nr_args > IORING_MAX_FIXED_FILES) | |
4820 | return -EMFILE; | |
4821 | ||
05f3fb3c JA |
4822 | ctx->file_data = kzalloc(sizeof(*ctx->file_data), GFP_KERNEL); |
4823 | if (!ctx->file_data) | |
4824 | return -ENOMEM; | |
4825 | ctx->file_data->ctx = ctx; | |
4826 | init_completion(&ctx->file_data->done); | |
4827 | ||
65e19f54 | 4828 | nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE); |
05f3fb3c JA |
4829 | ctx->file_data->table = kcalloc(nr_tables, |
4830 | sizeof(struct fixed_file_table), | |
65e19f54 | 4831 | GFP_KERNEL); |
05f3fb3c JA |
4832 | if (!ctx->file_data->table) { |
4833 | kfree(ctx->file_data); | |
4834 | ctx->file_data = NULL; | |
6b06314c | 4835 | return -ENOMEM; |
05f3fb3c JA |
4836 | } |
4837 | ||
4838 | if (percpu_ref_init(&ctx->file_data->refs, io_file_data_ref_zero, | |
4839 | PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) { | |
4840 | kfree(ctx->file_data->table); | |
4841 | kfree(ctx->file_data); | |
4842 | ctx->file_data = NULL; | |
4843 | return -ENOMEM; | |
4844 | } | |
4845 | ctx->file_data->put_llist.first = NULL; | |
4846 | INIT_WORK(&ctx->file_data->ref_work, io_ring_file_ref_switch); | |
6b06314c | 4847 | |
65e19f54 | 4848 | if (io_sqe_alloc_file_tables(ctx, nr_tables, nr_args)) { |
05f3fb3c JA |
4849 | percpu_ref_exit(&ctx->file_data->refs); |
4850 | kfree(ctx->file_data->table); | |
4851 | kfree(ctx->file_data); | |
4852 | ctx->file_data = NULL; | |
65e19f54 JA |
4853 | return -ENOMEM; |
4854 | } | |
4855 | ||
08a45173 | 4856 | for (i = 0; i < nr_args; i++, ctx->nr_user_files++) { |
65e19f54 JA |
4857 | struct fixed_file_table *table; |
4858 | unsigned index; | |
4859 | ||
6b06314c JA |
4860 | ret = -EFAULT; |
4861 | if (copy_from_user(&fd, &fds[i], sizeof(fd))) | |
4862 | break; | |
08a45173 JA |
4863 | /* allow sparse sets */ |
4864 | if (fd == -1) { | |
4865 | ret = 0; | |
4866 | continue; | |
4867 | } | |
6b06314c | 4868 | |
05f3fb3c | 4869 | table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT]; |
65e19f54 | 4870 | index = i & IORING_FILE_TABLE_MASK; |
05f3fb3c | 4871 | file = fget(fd); |
6b06314c JA |
4872 | |
4873 | ret = -EBADF; | |
05f3fb3c | 4874 | if (!file) |
6b06314c | 4875 | break; |
05f3fb3c | 4876 | |
6b06314c JA |
4877 | /* |
4878 | * Don't allow io_uring instances to be registered. If UNIX | |
4879 | * isn't enabled, then this causes a reference cycle and this | |
4880 | * instance can never get freed. If UNIX is enabled we'll | |
4881 | * handle it just fine, but there's still no point in allowing | |
4882 | * a ring fd as it doesn't support regular read/write anyway. | |
4883 | */ | |
05f3fb3c JA |
4884 | if (file->f_op == &io_uring_fops) { |
4885 | fput(file); | |
6b06314c JA |
4886 | break; |
4887 | } | |
6b06314c | 4888 | ret = 0; |
05f3fb3c | 4889 | table->files[index] = file; |
6b06314c JA |
4890 | } |
4891 | ||
4892 | if (ret) { | |
65e19f54 | 4893 | for (i = 0; i < ctx->nr_user_files; i++) { |
65e19f54 JA |
4894 | file = io_file_from_index(ctx, i); |
4895 | if (file) | |
4896 | fput(file); | |
4897 | } | |
4898 | for (i = 0; i < nr_tables; i++) | |
05f3fb3c | 4899 | kfree(ctx->file_data->table[i].files); |
6b06314c | 4900 | |
05f3fb3c JA |
4901 | kfree(ctx->file_data->table); |
4902 | kfree(ctx->file_data); | |
4903 | ctx->file_data = NULL; | |
6b06314c JA |
4904 | ctx->nr_user_files = 0; |
4905 | return ret; | |
4906 | } | |
4907 | ||
4908 | ret = io_sqe_files_scm(ctx); | |
4909 | if (ret) | |
4910 | io_sqe_files_unregister(ctx); | |
4911 | ||
4912 | return ret; | |
4913 | } | |
4914 | ||
c3a31e60 JA |
4915 | static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file, |
4916 | int index) | |
4917 | { | |
4918 | #if defined(CONFIG_UNIX) | |
4919 | struct sock *sock = ctx->ring_sock->sk; | |
4920 | struct sk_buff_head *head = &sock->sk_receive_queue; | |
4921 | struct sk_buff *skb; | |
4922 | ||
4923 | /* | |
4924 | * See if we can merge this file into an existing skb SCM_RIGHTS | |
4925 | * file set. If there's no room, fall back to allocating a new skb | |
4926 | * and filling it in. | |
4927 | */ | |
4928 | spin_lock_irq(&head->lock); | |
4929 | skb = skb_peek(head); | |
4930 | if (skb) { | |
4931 | struct scm_fp_list *fpl = UNIXCB(skb).fp; | |
4932 | ||
4933 | if (fpl->count < SCM_MAX_FD) { | |
4934 | __skb_unlink(skb, head); | |
4935 | spin_unlock_irq(&head->lock); | |
4936 | fpl->fp[fpl->count] = get_file(file); | |
4937 | unix_inflight(fpl->user, fpl->fp[fpl->count]); | |
4938 | fpl->count++; | |
4939 | spin_lock_irq(&head->lock); | |
4940 | __skb_queue_head(head, skb); | |
4941 | } else { | |
4942 | skb = NULL; | |
4943 | } | |
4944 | } | |
4945 | spin_unlock_irq(&head->lock); | |
4946 | ||
4947 | if (skb) { | |
4948 | fput(file); | |
4949 | return 0; | |
4950 | } | |
4951 | ||
4952 | return __io_sqe_files_scm(ctx, 1, index); | |
4953 | #else | |
4954 | return 0; | |
4955 | #endif | |
4956 | } | |
4957 | ||
05f3fb3c | 4958 | static void io_atomic_switch(struct percpu_ref *ref) |
c3a31e60 | 4959 | { |
05f3fb3c JA |
4960 | struct fixed_file_data *data; |
4961 | ||
4962 | data = container_of(ref, struct fixed_file_data, refs); | |
4963 | clear_bit(FFD_F_ATOMIC, &data->state); | |
4964 | } | |
4965 | ||
4966 | static bool io_queue_file_removal(struct fixed_file_data *data, | |
4967 | struct file *file) | |
4968 | { | |
4969 | struct io_file_put *pfile, pfile_stack; | |
4970 | DECLARE_COMPLETION_ONSTACK(done); | |
4971 | ||
4972 | /* | |
4973 | * If we fail allocating the struct we need for doing async reomval | |
4974 | * of this file, just punt to sync and wait for it. | |
4975 | */ | |
4976 | pfile = kzalloc(sizeof(*pfile), GFP_KERNEL); | |
4977 | if (!pfile) { | |
4978 | pfile = &pfile_stack; | |
4979 | pfile->done = &done; | |
4980 | } | |
4981 | ||
4982 | pfile->file = file; | |
4983 | llist_add(&pfile->llist, &data->put_llist); | |
4984 | ||
4985 | if (pfile == &pfile_stack) { | |
4986 | if (!test_and_set_bit(FFD_F_ATOMIC, &data->state)) { | |
4987 | percpu_ref_put(&data->refs); | |
4988 | percpu_ref_switch_to_atomic(&data->refs, | |
4989 | io_atomic_switch); | |
4990 | } | |
4991 | wait_for_completion(&done); | |
4992 | flush_work(&data->ref_work); | |
4993 | return false; | |
4994 | } | |
4995 | ||
4996 | return true; | |
4997 | } | |
4998 | ||
4999 | static int __io_sqe_files_update(struct io_ring_ctx *ctx, | |
5000 | struct io_uring_files_update *up, | |
5001 | unsigned nr_args) | |
5002 | { | |
5003 | struct fixed_file_data *data = ctx->file_data; | |
5004 | bool ref_switch = false; | |
5005 | struct file *file; | |
c3a31e60 JA |
5006 | __s32 __user *fds; |
5007 | int fd, i, err; | |
5008 | __u32 done; | |
5009 | ||
05f3fb3c | 5010 | if (check_add_overflow(up->offset, nr_args, &done)) |
c3a31e60 JA |
5011 | return -EOVERFLOW; |
5012 | if (done > ctx->nr_user_files) | |
5013 | return -EINVAL; | |
5014 | ||
5015 | done = 0; | |
05f3fb3c | 5016 | fds = u64_to_user_ptr(up->fds); |
c3a31e60 | 5017 | while (nr_args) { |
65e19f54 JA |
5018 | struct fixed_file_table *table; |
5019 | unsigned index; | |
5020 | ||
c3a31e60 JA |
5021 | err = 0; |
5022 | if (copy_from_user(&fd, &fds[done], sizeof(fd))) { | |
5023 | err = -EFAULT; | |
5024 | break; | |
5025 | } | |
05f3fb3c JA |
5026 | i = array_index_nospec(up->offset, ctx->nr_user_files); |
5027 | table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT]; | |
65e19f54 JA |
5028 | index = i & IORING_FILE_TABLE_MASK; |
5029 | if (table->files[index]) { | |
05f3fb3c | 5030 | file = io_file_from_index(ctx, index); |
65e19f54 | 5031 | table->files[index] = NULL; |
05f3fb3c JA |
5032 | if (io_queue_file_removal(data, file)) |
5033 | ref_switch = true; | |
c3a31e60 JA |
5034 | } |
5035 | if (fd != -1) { | |
c3a31e60 JA |
5036 | file = fget(fd); |
5037 | if (!file) { | |
5038 | err = -EBADF; | |
5039 | break; | |
5040 | } | |
5041 | /* | |
5042 | * Don't allow io_uring instances to be registered. If | |
5043 | * UNIX isn't enabled, then this causes a reference | |
5044 | * cycle and this instance can never get freed. If UNIX | |
5045 | * is enabled we'll handle it just fine, but there's | |
5046 | * still no point in allowing a ring fd as it doesn't | |
5047 | * support regular read/write anyway. | |
5048 | */ | |
5049 | if (file->f_op == &io_uring_fops) { | |
5050 | fput(file); | |
5051 | err = -EBADF; | |
5052 | break; | |
5053 | } | |
65e19f54 | 5054 | table->files[index] = file; |
c3a31e60 JA |
5055 | err = io_sqe_file_register(ctx, file, i); |
5056 | if (err) | |
5057 | break; | |
5058 | } | |
5059 | nr_args--; | |
5060 | done++; | |
05f3fb3c JA |
5061 | up->offset++; |
5062 | } | |
5063 | ||
5064 | if (ref_switch && !test_and_set_bit(FFD_F_ATOMIC, &data->state)) { | |
5065 | percpu_ref_put(&data->refs); | |
5066 | percpu_ref_switch_to_atomic(&data->refs, io_atomic_switch); | |
c3a31e60 JA |
5067 | } |
5068 | ||
5069 | return done ? done : err; | |
5070 | } | |
05f3fb3c JA |
5071 | static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg, |
5072 | unsigned nr_args) | |
5073 | { | |
5074 | struct io_uring_files_update up; | |
5075 | ||
5076 | if (!ctx->file_data) | |
5077 | return -ENXIO; | |
5078 | if (!nr_args) | |
5079 | return -EINVAL; | |
5080 | if (copy_from_user(&up, arg, sizeof(up))) | |
5081 | return -EFAULT; | |
5082 | if (up.resv) | |
5083 | return -EINVAL; | |
5084 | ||
5085 | return __io_sqe_files_update(ctx, &up, nr_args); | |
5086 | } | |
c3a31e60 | 5087 | |
7d723065 JA |
5088 | static void io_put_work(struct io_wq_work *work) |
5089 | { | |
5090 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); | |
5091 | ||
5092 | io_put_req(req); | |
5093 | } | |
5094 | ||
5095 | static void io_get_work(struct io_wq_work *work) | |
5096 | { | |
5097 | struct io_kiocb *req = container_of(work, struct io_kiocb, work); | |
5098 | ||
5099 | refcount_inc(&req->refs); | |
5100 | } | |
5101 | ||
6c271ce2 JA |
5102 | static int io_sq_offload_start(struct io_ring_ctx *ctx, |
5103 | struct io_uring_params *p) | |
2b188cc1 | 5104 | { |
576a347b | 5105 | struct io_wq_data data; |
561fb04a | 5106 | unsigned concurrency; |
2b188cc1 JA |
5107 | int ret; |
5108 | ||
6c271ce2 | 5109 | init_waitqueue_head(&ctx->sqo_wait); |
2b188cc1 JA |
5110 | mmgrab(current->mm); |
5111 | ctx->sqo_mm = current->mm; | |
5112 | ||
6c271ce2 | 5113 | if (ctx->flags & IORING_SETUP_SQPOLL) { |
3ec482d1 JA |
5114 | ret = -EPERM; |
5115 | if (!capable(CAP_SYS_ADMIN)) | |
5116 | goto err; | |
5117 | ||
917257da JA |
5118 | ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle); |
5119 | if (!ctx->sq_thread_idle) | |
5120 | ctx->sq_thread_idle = HZ; | |
5121 | ||
6c271ce2 | 5122 | if (p->flags & IORING_SETUP_SQ_AFF) { |
44a9bd18 | 5123 | int cpu = p->sq_thread_cpu; |
6c271ce2 | 5124 | |
917257da | 5125 | ret = -EINVAL; |
44a9bd18 JA |
5126 | if (cpu >= nr_cpu_ids) |
5127 | goto err; | |
7889f44d | 5128 | if (!cpu_online(cpu)) |
917257da JA |
5129 | goto err; |
5130 | ||
6c271ce2 JA |
5131 | ctx->sqo_thread = kthread_create_on_cpu(io_sq_thread, |
5132 | ctx, cpu, | |
5133 | "io_uring-sq"); | |
5134 | } else { | |
5135 | ctx->sqo_thread = kthread_create(io_sq_thread, ctx, | |
5136 | "io_uring-sq"); | |
5137 | } | |
5138 | if (IS_ERR(ctx->sqo_thread)) { | |
5139 | ret = PTR_ERR(ctx->sqo_thread); | |
5140 | ctx->sqo_thread = NULL; | |
5141 | goto err; | |
5142 | } | |
5143 | wake_up_process(ctx->sqo_thread); | |
5144 | } else if (p->flags & IORING_SETUP_SQ_AFF) { | |
5145 | /* Can't have SQ_AFF without SQPOLL */ | |
5146 | ret = -EINVAL; | |
5147 | goto err; | |
5148 | } | |
5149 | ||
576a347b JA |
5150 | data.mm = ctx->sqo_mm; |
5151 | data.user = ctx->user; | |
181e448d | 5152 | data.creds = ctx->creds; |
576a347b JA |
5153 | data.get_work = io_get_work; |
5154 | data.put_work = io_put_work; | |
5155 | ||
561fb04a JA |
5156 | /* Do QD, or 4 * CPUS, whatever is smallest */ |
5157 | concurrency = min(ctx->sq_entries, 4 * num_online_cpus()); | |
576a347b | 5158 | ctx->io_wq = io_wq_create(concurrency, &data); |
975c99a5 JA |
5159 | if (IS_ERR(ctx->io_wq)) { |
5160 | ret = PTR_ERR(ctx->io_wq); | |
5161 | ctx->io_wq = NULL; | |
2b188cc1 JA |
5162 | goto err; |
5163 | } | |
5164 | ||
5165 | return 0; | |
5166 | err: | |
54a91f3b | 5167 | io_finish_async(ctx); |
2b188cc1 JA |
5168 | mmdrop(ctx->sqo_mm); |
5169 | ctx->sqo_mm = NULL; | |
5170 | return ret; | |
5171 | } | |
5172 | ||
5173 | static void io_unaccount_mem(struct user_struct *user, unsigned long nr_pages) | |
5174 | { | |
5175 | atomic_long_sub(nr_pages, &user->locked_vm); | |
5176 | } | |
5177 | ||
5178 | static int io_account_mem(struct user_struct *user, unsigned long nr_pages) | |
5179 | { | |
5180 | unsigned long page_limit, cur_pages, new_pages; | |
5181 | ||
5182 | /* Don't allow more pages than we can safely lock */ | |
5183 | page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; | |
5184 | ||
5185 | do { | |
5186 | cur_pages = atomic_long_read(&user->locked_vm); | |
5187 | new_pages = cur_pages + nr_pages; | |
5188 | if (new_pages > page_limit) | |
5189 | return -ENOMEM; | |
5190 | } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages, | |
5191 | new_pages) != cur_pages); | |
5192 | ||
5193 | return 0; | |
5194 | } | |
5195 | ||
5196 | static void io_mem_free(void *ptr) | |
5197 | { | |
52e04ef4 MR |
5198 | struct page *page; |
5199 | ||
5200 | if (!ptr) | |
5201 | return; | |
2b188cc1 | 5202 | |
52e04ef4 | 5203 | page = virt_to_head_page(ptr); |
2b188cc1 JA |
5204 | if (put_page_testzero(page)) |
5205 | free_compound_page(page); | |
5206 | } | |
5207 | ||
5208 | static void *io_mem_alloc(size_t size) | |
5209 | { | |
5210 | gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP | | |
5211 | __GFP_NORETRY; | |
5212 | ||
5213 | return (void *) __get_free_pages(gfp_flags, get_order(size)); | |
5214 | } | |
5215 | ||
75b28aff HV |
5216 | static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries, |
5217 | size_t *sq_offset) | |
5218 | { | |
5219 | struct io_rings *rings; | |
5220 | size_t off, sq_array_size; | |
5221 | ||
5222 | off = struct_size(rings, cqes, cq_entries); | |
5223 | if (off == SIZE_MAX) | |
5224 | return SIZE_MAX; | |
5225 | ||
5226 | #ifdef CONFIG_SMP | |
5227 | off = ALIGN(off, SMP_CACHE_BYTES); | |
5228 | if (off == 0) | |
5229 | return SIZE_MAX; | |
5230 | #endif | |
5231 | ||
5232 | sq_array_size = array_size(sizeof(u32), sq_entries); | |
5233 | if (sq_array_size == SIZE_MAX) | |
5234 | return SIZE_MAX; | |
5235 | ||
5236 | if (check_add_overflow(off, sq_array_size, &off)) | |
5237 | return SIZE_MAX; | |
5238 | ||
5239 | if (sq_offset) | |
5240 | *sq_offset = off; | |
5241 | ||
5242 | return off; | |
5243 | } | |
5244 | ||
2b188cc1 JA |
5245 | static unsigned long ring_pages(unsigned sq_entries, unsigned cq_entries) |
5246 | { | |
75b28aff | 5247 | size_t pages; |
2b188cc1 | 5248 | |
75b28aff HV |
5249 | pages = (size_t)1 << get_order( |
5250 | rings_size(sq_entries, cq_entries, NULL)); | |
5251 | pages += (size_t)1 << get_order( | |
5252 | array_size(sizeof(struct io_uring_sqe), sq_entries)); | |
2b188cc1 | 5253 | |
75b28aff | 5254 | return pages; |
2b188cc1 JA |
5255 | } |
5256 | ||
edafccee JA |
5257 | static int io_sqe_buffer_unregister(struct io_ring_ctx *ctx) |
5258 | { | |
5259 | int i, j; | |
5260 | ||
5261 | if (!ctx->user_bufs) | |
5262 | return -ENXIO; | |
5263 | ||
5264 | for (i = 0; i < ctx->nr_user_bufs; i++) { | |
5265 | struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; | |
5266 | ||
5267 | for (j = 0; j < imu->nr_bvecs; j++) | |
27c4d3a3 | 5268 | put_user_page(imu->bvec[j].bv_page); |
edafccee JA |
5269 | |
5270 | if (ctx->account_mem) | |
5271 | io_unaccount_mem(ctx->user, imu->nr_bvecs); | |
d4ef6475 | 5272 | kvfree(imu->bvec); |
edafccee JA |
5273 | imu->nr_bvecs = 0; |
5274 | } | |
5275 | ||
5276 | kfree(ctx->user_bufs); | |
5277 | ctx->user_bufs = NULL; | |
5278 | ctx->nr_user_bufs = 0; | |
5279 | return 0; | |
5280 | } | |
5281 | ||
5282 | static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, | |
5283 | void __user *arg, unsigned index) | |
5284 | { | |
5285 | struct iovec __user *src; | |
5286 | ||
5287 | #ifdef CONFIG_COMPAT | |
5288 | if (ctx->compat) { | |
5289 | struct compat_iovec __user *ciovs; | |
5290 | struct compat_iovec ciov; | |
5291 | ||
5292 | ciovs = (struct compat_iovec __user *) arg; | |
5293 | if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov))) | |
5294 | return -EFAULT; | |
5295 | ||
d55e5f5b | 5296 | dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base); |
edafccee JA |
5297 | dst->iov_len = ciov.iov_len; |
5298 | return 0; | |
5299 | } | |
5300 | #endif | |
5301 | src = (struct iovec __user *) arg; | |
5302 | if (copy_from_user(dst, &src[index], sizeof(*dst))) | |
5303 | return -EFAULT; | |
5304 | return 0; | |
5305 | } | |
5306 | ||
5307 | static int io_sqe_buffer_register(struct io_ring_ctx *ctx, void __user *arg, | |
5308 | unsigned nr_args) | |
5309 | { | |
5310 | struct vm_area_struct **vmas = NULL; | |
5311 | struct page **pages = NULL; | |
5312 | int i, j, got_pages = 0; | |
5313 | int ret = -EINVAL; | |
5314 | ||
5315 | if (ctx->user_bufs) | |
5316 | return -EBUSY; | |
5317 | if (!nr_args || nr_args > UIO_MAXIOV) | |
5318 | return -EINVAL; | |
5319 | ||
5320 | ctx->user_bufs = kcalloc(nr_args, sizeof(struct io_mapped_ubuf), | |
5321 | GFP_KERNEL); | |
5322 | if (!ctx->user_bufs) | |
5323 | return -ENOMEM; | |
5324 | ||
5325 | for (i = 0; i < nr_args; i++) { | |
5326 | struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; | |
5327 | unsigned long off, start, end, ubuf; | |
5328 | int pret, nr_pages; | |
5329 | struct iovec iov; | |
5330 | size_t size; | |
5331 | ||
5332 | ret = io_copy_iov(ctx, &iov, arg, i); | |
5333 | if (ret) | |
a278682d | 5334 | goto err; |
edafccee JA |
5335 | |
5336 | /* | |
5337 | * Don't impose further limits on the size and buffer | |
5338 | * constraints here, we'll -EINVAL later when IO is | |
5339 | * submitted if they are wrong. | |
5340 | */ | |
5341 | ret = -EFAULT; | |
5342 | if (!iov.iov_base || !iov.iov_len) | |
5343 | goto err; | |
5344 | ||
5345 | /* arbitrary limit, but we need something */ | |
5346 | if (iov.iov_len > SZ_1G) | |
5347 | goto err; | |
5348 | ||
5349 | ubuf = (unsigned long) iov.iov_base; | |
5350 | end = (ubuf + iov.iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
5351 | start = ubuf >> PAGE_SHIFT; | |
5352 | nr_pages = end - start; | |
5353 | ||
5354 | if (ctx->account_mem) { | |
5355 | ret = io_account_mem(ctx->user, nr_pages); | |
5356 | if (ret) | |
5357 | goto err; | |
5358 | } | |
5359 | ||
5360 | ret = 0; | |
5361 | if (!pages || nr_pages > got_pages) { | |
5362 | kfree(vmas); | |
5363 | kfree(pages); | |
d4ef6475 | 5364 | pages = kvmalloc_array(nr_pages, sizeof(struct page *), |
edafccee | 5365 | GFP_KERNEL); |
d4ef6475 | 5366 | vmas = kvmalloc_array(nr_pages, |
edafccee JA |
5367 | sizeof(struct vm_area_struct *), |
5368 | GFP_KERNEL); | |
5369 | if (!pages || !vmas) { | |
5370 | ret = -ENOMEM; | |
5371 | if (ctx->account_mem) | |
5372 | io_unaccount_mem(ctx->user, nr_pages); | |
5373 | goto err; | |
5374 | } | |
5375 | got_pages = nr_pages; | |
5376 | } | |
5377 | ||
d4ef6475 | 5378 | imu->bvec = kvmalloc_array(nr_pages, sizeof(struct bio_vec), |
edafccee JA |
5379 | GFP_KERNEL); |
5380 | ret = -ENOMEM; | |
5381 | if (!imu->bvec) { | |
5382 | if (ctx->account_mem) | |
5383 | io_unaccount_mem(ctx->user, nr_pages); | |
5384 | goto err; | |
5385 | } | |
5386 | ||
5387 | ret = 0; | |
5388 | down_read(¤t->mm->mmap_sem); | |
932f4a63 IW |
5389 | pret = get_user_pages(ubuf, nr_pages, |
5390 | FOLL_WRITE | FOLL_LONGTERM, | |
5391 | pages, vmas); | |
edafccee JA |
5392 | if (pret == nr_pages) { |
5393 | /* don't support file backed memory */ | |
5394 | for (j = 0; j < nr_pages; j++) { | |
5395 | struct vm_area_struct *vma = vmas[j]; | |
5396 | ||
5397 | if (vma->vm_file && | |
5398 | !is_file_hugepages(vma->vm_file)) { | |
5399 | ret = -EOPNOTSUPP; | |
5400 | break; | |
5401 | } | |
5402 | } | |
5403 | } else { | |
5404 | ret = pret < 0 ? pret : -EFAULT; | |
5405 | } | |
5406 | up_read(¤t->mm->mmap_sem); | |
5407 | if (ret) { | |
5408 | /* | |
5409 | * if we did partial map, or found file backed vmas, | |
5410 | * release any pages we did get | |
5411 | */ | |
27c4d3a3 JH |
5412 | if (pret > 0) |
5413 | put_user_pages(pages, pret); | |
edafccee JA |
5414 | if (ctx->account_mem) |
5415 | io_unaccount_mem(ctx->user, nr_pages); | |
d4ef6475 | 5416 | kvfree(imu->bvec); |
edafccee JA |
5417 | goto err; |
5418 | } | |
5419 | ||
5420 | off = ubuf & ~PAGE_MASK; | |
5421 | size = iov.iov_len; | |
5422 | for (j = 0; j < nr_pages; j++) { | |
5423 | size_t vec_len; | |
5424 | ||
5425 | vec_len = min_t(size_t, size, PAGE_SIZE - off); | |
5426 | imu->bvec[j].bv_page = pages[j]; | |
5427 | imu->bvec[j].bv_len = vec_len; | |
5428 | imu->bvec[j].bv_offset = off; | |
5429 | off = 0; | |
5430 | size -= vec_len; | |
5431 | } | |
5432 | /* store original address for later verification */ | |
5433 | imu->ubuf = ubuf; | |
5434 | imu->len = iov.iov_len; | |
5435 | imu->nr_bvecs = nr_pages; | |
5436 | ||
5437 | ctx->nr_user_bufs++; | |
5438 | } | |
d4ef6475 MR |
5439 | kvfree(pages); |
5440 | kvfree(vmas); | |
edafccee JA |
5441 | return 0; |
5442 | err: | |
d4ef6475 MR |
5443 | kvfree(pages); |
5444 | kvfree(vmas); | |
edafccee JA |
5445 | io_sqe_buffer_unregister(ctx); |
5446 | return ret; | |
5447 | } | |
5448 | ||
9b402849 JA |
5449 | static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg) |
5450 | { | |
5451 | __s32 __user *fds = arg; | |
5452 | int fd; | |
5453 | ||
5454 | if (ctx->cq_ev_fd) | |
5455 | return -EBUSY; | |
5456 | ||
5457 | if (copy_from_user(&fd, fds, sizeof(*fds))) | |
5458 | return -EFAULT; | |
5459 | ||
5460 | ctx->cq_ev_fd = eventfd_ctx_fdget(fd); | |
5461 | if (IS_ERR(ctx->cq_ev_fd)) { | |
5462 | int ret = PTR_ERR(ctx->cq_ev_fd); | |
5463 | ctx->cq_ev_fd = NULL; | |
5464 | return ret; | |
5465 | } | |
5466 | ||
5467 | return 0; | |
5468 | } | |
5469 | ||
5470 | static int io_eventfd_unregister(struct io_ring_ctx *ctx) | |
5471 | { | |
5472 | if (ctx->cq_ev_fd) { | |
5473 | eventfd_ctx_put(ctx->cq_ev_fd); | |
5474 | ctx->cq_ev_fd = NULL; | |
5475 | return 0; | |
5476 | } | |
5477 | ||
5478 | return -ENXIO; | |
5479 | } | |
5480 | ||
2b188cc1 JA |
5481 | static void io_ring_ctx_free(struct io_ring_ctx *ctx) |
5482 | { | |
6b06314c | 5483 | io_finish_async(ctx); |
2b188cc1 JA |
5484 | if (ctx->sqo_mm) |
5485 | mmdrop(ctx->sqo_mm); | |
def596e9 JA |
5486 | |
5487 | io_iopoll_reap_events(ctx); | |
edafccee | 5488 | io_sqe_buffer_unregister(ctx); |
6b06314c | 5489 | io_sqe_files_unregister(ctx); |
9b402849 | 5490 | io_eventfd_unregister(ctx); |
def596e9 | 5491 | |
2b188cc1 | 5492 | #if defined(CONFIG_UNIX) |
355e8d26 EB |
5493 | if (ctx->ring_sock) { |
5494 | ctx->ring_sock->file = NULL; /* so that iput() is called */ | |
2b188cc1 | 5495 | sock_release(ctx->ring_sock); |
355e8d26 | 5496 | } |
2b188cc1 JA |
5497 | #endif |
5498 | ||
75b28aff | 5499 | io_mem_free(ctx->rings); |
2b188cc1 | 5500 | io_mem_free(ctx->sq_sqes); |
2b188cc1 JA |
5501 | |
5502 | percpu_ref_exit(&ctx->refs); | |
5503 | if (ctx->account_mem) | |
5504 | io_unaccount_mem(ctx->user, | |
5505 | ring_pages(ctx->sq_entries, ctx->cq_entries)); | |
5506 | free_uid(ctx->user); | |
181e448d | 5507 | put_cred(ctx->creds); |
206aefde | 5508 | kfree(ctx->completions); |
78076bb6 | 5509 | kfree(ctx->cancel_hash); |
0ddf92e8 | 5510 | kmem_cache_free(req_cachep, ctx->fallback_req); |
2b188cc1 JA |
5511 | kfree(ctx); |
5512 | } | |
5513 | ||
5514 | static __poll_t io_uring_poll(struct file *file, poll_table *wait) | |
5515 | { | |
5516 | struct io_ring_ctx *ctx = file->private_data; | |
5517 | __poll_t mask = 0; | |
5518 | ||
5519 | poll_wait(file, &ctx->cq_wait, wait); | |
4f7067c3 SB |
5520 | /* |
5521 | * synchronizes with barrier from wq_has_sleeper call in | |
5522 | * io_commit_cqring | |
5523 | */ | |
2b188cc1 | 5524 | smp_rmb(); |
75b28aff HV |
5525 | if (READ_ONCE(ctx->rings->sq.tail) - ctx->cached_sq_head != |
5526 | ctx->rings->sq_ring_entries) | |
2b188cc1 | 5527 | mask |= EPOLLOUT | EPOLLWRNORM; |
daa5de54 | 5528 | if (READ_ONCE(ctx->rings->cq.head) != ctx->cached_cq_tail) |
2b188cc1 JA |
5529 | mask |= EPOLLIN | EPOLLRDNORM; |
5530 | ||
5531 | return mask; | |
5532 | } | |
5533 | ||
5534 | static int io_uring_fasync(int fd, struct file *file, int on) | |
5535 | { | |
5536 | struct io_ring_ctx *ctx = file->private_data; | |
5537 | ||
5538 | return fasync_helper(fd, file, on, &ctx->cq_fasync); | |
5539 | } | |
5540 | ||
5541 | static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) | |
5542 | { | |
5543 | mutex_lock(&ctx->uring_lock); | |
5544 | percpu_ref_kill(&ctx->refs); | |
5545 | mutex_unlock(&ctx->uring_lock); | |
5546 | ||
5262f567 | 5547 | io_kill_timeouts(ctx); |
221c5eb2 | 5548 | io_poll_remove_all(ctx); |
561fb04a JA |
5549 | |
5550 | if (ctx->io_wq) | |
5551 | io_wq_cancel_all(ctx->io_wq); | |
5552 | ||
def596e9 | 5553 | io_iopoll_reap_events(ctx); |
15dff286 JA |
5554 | /* if we failed setting up the ctx, we might not have any rings */ |
5555 | if (ctx->rings) | |
5556 | io_cqring_overflow_flush(ctx, true); | |
206aefde | 5557 | wait_for_completion(&ctx->completions[0]); |
2b188cc1 JA |
5558 | io_ring_ctx_free(ctx); |
5559 | } | |
5560 | ||
5561 | static int io_uring_release(struct inode *inode, struct file *file) | |
5562 | { | |
5563 | struct io_ring_ctx *ctx = file->private_data; | |
5564 | ||
5565 | file->private_data = NULL; | |
5566 | io_ring_ctx_wait_and_kill(ctx); | |
5567 | return 0; | |
5568 | } | |
5569 | ||
fcb323cc JA |
5570 | static void io_uring_cancel_files(struct io_ring_ctx *ctx, |
5571 | struct files_struct *files) | |
5572 | { | |
5573 | struct io_kiocb *req; | |
5574 | DEFINE_WAIT(wait); | |
5575 | ||
5576 | while (!list_empty_careful(&ctx->inflight_list)) { | |
768134d4 | 5577 | struct io_kiocb *cancel_req = NULL; |
fcb323cc JA |
5578 | |
5579 | spin_lock_irq(&ctx->inflight_lock); | |
5580 | list_for_each_entry(req, &ctx->inflight_list, inflight_entry) { | |
768134d4 JA |
5581 | if (req->work.files != files) |
5582 | continue; | |
5583 | /* req is being completed, ignore */ | |
5584 | if (!refcount_inc_not_zero(&req->refs)) | |
5585 | continue; | |
5586 | cancel_req = req; | |
5587 | break; | |
fcb323cc | 5588 | } |
768134d4 | 5589 | if (cancel_req) |
fcb323cc | 5590 | prepare_to_wait(&ctx->inflight_wait, &wait, |
768134d4 | 5591 | TASK_UNINTERRUPTIBLE); |
fcb323cc JA |
5592 | spin_unlock_irq(&ctx->inflight_lock); |
5593 | ||
768134d4 JA |
5594 | /* We need to keep going until we don't find a matching req */ |
5595 | if (!cancel_req) | |
fcb323cc | 5596 | break; |
2f6d9b9d BL |
5597 | |
5598 | io_wq_cancel_work(ctx->io_wq, &cancel_req->work); | |
5599 | io_put_req(cancel_req); | |
fcb323cc JA |
5600 | schedule(); |
5601 | } | |
768134d4 | 5602 | finish_wait(&ctx->inflight_wait, &wait); |
fcb323cc JA |
5603 | } |
5604 | ||
5605 | static int io_uring_flush(struct file *file, void *data) | |
5606 | { | |
5607 | struct io_ring_ctx *ctx = file->private_data; | |
5608 | ||
5609 | io_uring_cancel_files(ctx, data); | |
1d7bb1d5 JA |
5610 | if (fatal_signal_pending(current) || (current->flags & PF_EXITING)) { |
5611 | io_cqring_overflow_flush(ctx, true); | |
fcb323cc | 5612 | io_wq_cancel_all(ctx->io_wq); |
1d7bb1d5 | 5613 | } |
fcb323cc JA |
5614 | return 0; |
5615 | } | |
5616 | ||
6c5c240e RP |
5617 | static void *io_uring_validate_mmap_request(struct file *file, |
5618 | loff_t pgoff, size_t sz) | |
2b188cc1 | 5619 | { |
2b188cc1 | 5620 | struct io_ring_ctx *ctx = file->private_data; |
6c5c240e | 5621 | loff_t offset = pgoff << PAGE_SHIFT; |
2b188cc1 JA |
5622 | struct page *page; |
5623 | void *ptr; | |
5624 | ||
5625 | switch (offset) { | |
5626 | case IORING_OFF_SQ_RING: | |
75b28aff HV |
5627 | case IORING_OFF_CQ_RING: |
5628 | ptr = ctx->rings; | |
2b188cc1 JA |
5629 | break; |
5630 | case IORING_OFF_SQES: | |
5631 | ptr = ctx->sq_sqes; | |
5632 | break; | |
2b188cc1 | 5633 | default: |
6c5c240e | 5634 | return ERR_PTR(-EINVAL); |
2b188cc1 JA |
5635 | } |
5636 | ||
5637 | page = virt_to_head_page(ptr); | |
a50b854e | 5638 | if (sz > page_size(page)) |
6c5c240e RP |
5639 | return ERR_PTR(-EINVAL); |
5640 | ||
5641 | return ptr; | |
5642 | } | |
5643 | ||
5644 | #ifdef CONFIG_MMU | |
5645 | ||
5646 | static int io_uring_mmap(struct file *file, struct vm_area_struct *vma) | |
5647 | { | |
5648 | size_t sz = vma->vm_end - vma->vm_start; | |
5649 | unsigned long pfn; | |
5650 | void *ptr; | |
5651 | ||
5652 | ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz); | |
5653 | if (IS_ERR(ptr)) | |
5654 | return PTR_ERR(ptr); | |
2b188cc1 JA |
5655 | |
5656 | pfn = virt_to_phys(ptr) >> PAGE_SHIFT; | |
5657 | return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot); | |
5658 | } | |
5659 | ||
6c5c240e RP |
5660 | #else /* !CONFIG_MMU */ |
5661 | ||
5662 | static int io_uring_mmap(struct file *file, struct vm_area_struct *vma) | |
5663 | { | |
5664 | return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL; | |
5665 | } | |
5666 | ||
5667 | static unsigned int io_uring_nommu_mmap_capabilities(struct file *file) | |
5668 | { | |
5669 | return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE; | |
5670 | } | |
5671 | ||
5672 | static unsigned long io_uring_nommu_get_unmapped_area(struct file *file, | |
5673 | unsigned long addr, unsigned long len, | |
5674 | unsigned long pgoff, unsigned long flags) | |
5675 | { | |
5676 | void *ptr; | |
5677 | ||
5678 | ptr = io_uring_validate_mmap_request(file, pgoff, len); | |
5679 | if (IS_ERR(ptr)) | |
5680 | return PTR_ERR(ptr); | |
5681 | ||
5682 | return (unsigned long) ptr; | |
5683 | } | |
5684 | ||
5685 | #endif /* !CONFIG_MMU */ | |
5686 | ||
2b188cc1 JA |
5687 | SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, |
5688 | u32, min_complete, u32, flags, const sigset_t __user *, sig, | |
5689 | size_t, sigsz) | |
5690 | { | |
5691 | struct io_ring_ctx *ctx; | |
5692 | long ret = -EBADF; | |
5693 | int submitted = 0; | |
5694 | struct fd f; | |
5695 | ||
6c271ce2 | 5696 | if (flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP)) |
2b188cc1 JA |
5697 | return -EINVAL; |
5698 | ||
5699 | f = fdget(fd); | |
5700 | if (!f.file) | |
5701 | return -EBADF; | |
5702 | ||
5703 | ret = -EOPNOTSUPP; | |
5704 | if (f.file->f_op != &io_uring_fops) | |
5705 | goto out_fput; | |
5706 | ||
5707 | ret = -ENXIO; | |
5708 | ctx = f.file->private_data; | |
5709 | if (!percpu_ref_tryget(&ctx->refs)) | |
5710 | goto out_fput; | |
5711 | ||
6c271ce2 JA |
5712 | /* |
5713 | * For SQ polling, the thread will do all submissions and completions. | |
5714 | * Just return the requested submit count, and wake the thread if | |
5715 | * we were asked to. | |
5716 | */ | |
b2a9eada | 5717 | ret = 0; |
6c271ce2 | 5718 | if (ctx->flags & IORING_SETUP_SQPOLL) { |
c1edbf5f JA |
5719 | if (!list_empty_careful(&ctx->cq_overflow_list)) |
5720 | io_cqring_overflow_flush(ctx, false); | |
6c271ce2 JA |
5721 | if (flags & IORING_ENTER_SQ_WAKEUP) |
5722 | wake_up(&ctx->sqo_wait); | |
5723 | submitted = to_submit; | |
b2a9eada | 5724 | } else if (to_submit) { |
ae9428ca | 5725 | struct mm_struct *cur_mm; |
2b188cc1 | 5726 | |
44d28279 JA |
5727 | if (current->mm != ctx->sqo_mm || |
5728 | current_cred() != ctx->creds) { | |
5729 | ret = -EPERM; | |
5730 | goto out; | |
5731 | } | |
5732 | ||
ae9428ca | 5733 | to_submit = min(to_submit, ctx->sq_entries); |
2b188cc1 | 5734 | mutex_lock(&ctx->uring_lock); |
ae9428ca PB |
5735 | /* already have mm, so io_submit_sqes() won't try to grab it */ |
5736 | cur_mm = ctx->sqo_mm; | |
5737 | submitted = io_submit_sqes(ctx, to_submit, f.file, fd, | |
5738 | &cur_mm, false); | |
2b188cc1 | 5739 | mutex_unlock(&ctx->uring_lock); |
7c504e65 PB |
5740 | |
5741 | if (submitted != to_submit) | |
5742 | goto out; | |
2b188cc1 JA |
5743 | } |
5744 | if (flags & IORING_ENTER_GETEVENTS) { | |
def596e9 JA |
5745 | unsigned nr_events = 0; |
5746 | ||
2b188cc1 JA |
5747 | min_complete = min(min_complete, ctx->cq_entries); |
5748 | ||
def596e9 | 5749 | if (ctx->flags & IORING_SETUP_IOPOLL) { |
def596e9 | 5750 | ret = io_iopoll_check(ctx, &nr_events, min_complete); |
def596e9 JA |
5751 | } else { |
5752 | ret = io_cqring_wait(ctx, min_complete, sig, sigsz); | |
5753 | } | |
2b188cc1 JA |
5754 | } |
5755 | ||
7c504e65 | 5756 | out: |
6805b32e | 5757 | percpu_ref_put(&ctx->refs); |
2b188cc1 JA |
5758 | out_fput: |
5759 | fdput(f); | |
5760 | return submitted ? submitted : ret; | |
5761 | } | |
5762 | ||
5763 | static const struct file_operations io_uring_fops = { | |
5764 | .release = io_uring_release, | |
fcb323cc | 5765 | .flush = io_uring_flush, |
2b188cc1 | 5766 | .mmap = io_uring_mmap, |
6c5c240e RP |
5767 | #ifndef CONFIG_MMU |
5768 | .get_unmapped_area = io_uring_nommu_get_unmapped_area, | |
5769 | .mmap_capabilities = io_uring_nommu_mmap_capabilities, | |
5770 | #endif | |
2b188cc1 JA |
5771 | .poll = io_uring_poll, |
5772 | .fasync = io_uring_fasync, | |
5773 | }; | |
5774 | ||
5775 | static int io_allocate_scq_urings(struct io_ring_ctx *ctx, | |
5776 | struct io_uring_params *p) | |
5777 | { | |
75b28aff HV |
5778 | struct io_rings *rings; |
5779 | size_t size, sq_array_offset; | |
2b188cc1 | 5780 | |
75b28aff HV |
5781 | size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset); |
5782 | if (size == SIZE_MAX) | |
5783 | return -EOVERFLOW; | |
5784 | ||
5785 | rings = io_mem_alloc(size); | |
5786 | if (!rings) | |
2b188cc1 JA |
5787 | return -ENOMEM; |
5788 | ||
75b28aff HV |
5789 | ctx->rings = rings; |
5790 | ctx->sq_array = (u32 *)((char *)rings + sq_array_offset); | |
5791 | rings->sq_ring_mask = p->sq_entries - 1; | |
5792 | rings->cq_ring_mask = p->cq_entries - 1; | |
5793 | rings->sq_ring_entries = p->sq_entries; | |
5794 | rings->cq_ring_entries = p->cq_entries; | |
5795 | ctx->sq_mask = rings->sq_ring_mask; | |
5796 | ctx->cq_mask = rings->cq_ring_mask; | |
5797 | ctx->sq_entries = rings->sq_ring_entries; | |
5798 | ctx->cq_entries = rings->cq_ring_entries; | |
2b188cc1 JA |
5799 | |
5800 | size = array_size(sizeof(struct io_uring_sqe), p->sq_entries); | |
eb065d30 JA |
5801 | if (size == SIZE_MAX) { |
5802 | io_mem_free(ctx->rings); | |
5803 | ctx->rings = NULL; | |
2b188cc1 | 5804 | return -EOVERFLOW; |
eb065d30 | 5805 | } |
2b188cc1 JA |
5806 | |
5807 | ctx->sq_sqes = io_mem_alloc(size); | |
eb065d30 JA |
5808 | if (!ctx->sq_sqes) { |
5809 | io_mem_free(ctx->rings); | |
5810 | ctx->rings = NULL; | |
2b188cc1 | 5811 | return -ENOMEM; |
eb065d30 | 5812 | } |
2b188cc1 | 5813 | |
2b188cc1 JA |
5814 | return 0; |
5815 | } | |
5816 | ||
5817 | /* | |
5818 | * Allocate an anonymous fd, this is what constitutes the application | |
5819 | * visible backing of an io_uring instance. The application mmaps this | |
5820 | * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled, | |
5821 | * we have to tie this fd to a socket for file garbage collection purposes. | |
5822 | */ | |
5823 | static int io_uring_get_fd(struct io_ring_ctx *ctx) | |
5824 | { | |
5825 | struct file *file; | |
5826 | int ret; | |
5827 | ||
5828 | #if defined(CONFIG_UNIX) | |
5829 | ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP, | |
5830 | &ctx->ring_sock); | |
5831 | if (ret) | |
5832 | return ret; | |
5833 | #endif | |
5834 | ||
5835 | ret = get_unused_fd_flags(O_RDWR | O_CLOEXEC); | |
5836 | if (ret < 0) | |
5837 | goto err; | |
5838 | ||
5839 | file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx, | |
5840 | O_RDWR | O_CLOEXEC); | |
5841 | if (IS_ERR(file)) { | |
5842 | put_unused_fd(ret); | |
5843 | ret = PTR_ERR(file); | |
5844 | goto err; | |
5845 | } | |
5846 | ||
5847 | #if defined(CONFIG_UNIX) | |
5848 | ctx->ring_sock->file = file; | |
5849 | #endif | |
5850 | fd_install(ret, file); | |
5851 | return ret; | |
5852 | err: | |
5853 | #if defined(CONFIG_UNIX) | |
5854 | sock_release(ctx->ring_sock); | |
5855 | ctx->ring_sock = NULL; | |
5856 | #endif | |
5857 | return ret; | |
5858 | } | |
5859 | ||
5860 | static int io_uring_create(unsigned entries, struct io_uring_params *p) | |
5861 | { | |
5862 | struct user_struct *user = NULL; | |
5863 | struct io_ring_ctx *ctx; | |
5864 | bool account_mem; | |
5865 | int ret; | |
5866 | ||
5867 | if (!entries || entries > IORING_MAX_ENTRIES) | |
5868 | return -EINVAL; | |
5869 | ||
5870 | /* | |
5871 | * Use twice as many entries for the CQ ring. It's possible for the | |
5872 | * application to drive a higher depth than the size of the SQ ring, | |
5873 | * since the sqes are only used at submission time. This allows for | |
33a107f0 JA |
5874 | * some flexibility in overcommitting a bit. If the application has |
5875 | * set IORING_SETUP_CQSIZE, it will have passed in the desired number | |
5876 | * of CQ ring entries manually. | |
2b188cc1 JA |
5877 | */ |
5878 | p->sq_entries = roundup_pow_of_two(entries); | |
33a107f0 JA |
5879 | if (p->flags & IORING_SETUP_CQSIZE) { |
5880 | /* | |
5881 | * If IORING_SETUP_CQSIZE is set, we do the same roundup | |
5882 | * to a power-of-two, if it isn't already. We do NOT impose | |
5883 | * any cq vs sq ring sizing. | |
5884 | */ | |
5885 | if (p->cq_entries < p->sq_entries || p->cq_entries > IORING_MAX_CQ_ENTRIES) | |
5886 | return -EINVAL; | |
5887 | p->cq_entries = roundup_pow_of_two(p->cq_entries); | |
5888 | } else { | |
5889 | p->cq_entries = 2 * p->sq_entries; | |
5890 | } | |
2b188cc1 JA |
5891 | |
5892 | user = get_uid(current_user()); | |
5893 | account_mem = !capable(CAP_IPC_LOCK); | |
5894 | ||
5895 | if (account_mem) { | |
5896 | ret = io_account_mem(user, | |
5897 | ring_pages(p->sq_entries, p->cq_entries)); | |
5898 | if (ret) { | |
5899 | free_uid(user); | |
5900 | return ret; | |
5901 | } | |
5902 | } | |
5903 | ||
5904 | ctx = io_ring_ctx_alloc(p); | |
5905 | if (!ctx) { | |
5906 | if (account_mem) | |
5907 | io_unaccount_mem(user, ring_pages(p->sq_entries, | |
5908 | p->cq_entries)); | |
5909 | free_uid(user); | |
5910 | return -ENOMEM; | |
5911 | } | |
5912 | ctx->compat = in_compat_syscall(); | |
5913 | ctx->account_mem = account_mem; | |
5914 | ctx->user = user; | |
0b8c0ec7 | 5915 | ctx->creds = get_current_cred(); |
2b188cc1 JA |
5916 | |
5917 | ret = io_allocate_scq_urings(ctx, p); | |
5918 | if (ret) | |
5919 | goto err; | |
5920 | ||
6c271ce2 | 5921 | ret = io_sq_offload_start(ctx, p); |
2b188cc1 JA |
5922 | if (ret) |
5923 | goto err; | |
5924 | ||
2b188cc1 | 5925 | memset(&p->sq_off, 0, sizeof(p->sq_off)); |
75b28aff HV |
5926 | p->sq_off.head = offsetof(struct io_rings, sq.head); |
5927 | p->sq_off.tail = offsetof(struct io_rings, sq.tail); | |
5928 | p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask); | |
5929 | p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries); | |
5930 | p->sq_off.flags = offsetof(struct io_rings, sq_flags); | |
5931 | p->sq_off.dropped = offsetof(struct io_rings, sq_dropped); | |
5932 | p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings; | |
2b188cc1 JA |
5933 | |
5934 | memset(&p->cq_off, 0, sizeof(p->cq_off)); | |
75b28aff HV |
5935 | p->cq_off.head = offsetof(struct io_rings, cq.head); |
5936 | p->cq_off.tail = offsetof(struct io_rings, cq.tail); | |
5937 | p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask); | |
5938 | p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries); | |
5939 | p->cq_off.overflow = offsetof(struct io_rings, cq_overflow); | |
5940 | p->cq_off.cqes = offsetof(struct io_rings, cqes); | |
ac90f249 | 5941 | |
044c1ab3 JA |
5942 | /* |
5943 | * Install ring fd as the very last thing, so we don't risk someone | |
5944 | * having closed it before we finish setup | |
5945 | */ | |
5946 | ret = io_uring_get_fd(ctx); | |
5947 | if (ret < 0) | |
5948 | goto err; | |
5949 | ||
da8c9690 JA |
5950 | p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP | |
5951 | IORING_FEAT_SUBMIT_STABLE; | |
c826bd7a | 5952 | trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags); |
2b188cc1 JA |
5953 | return ret; |
5954 | err: | |
5955 | io_ring_ctx_wait_and_kill(ctx); | |
5956 | return ret; | |
5957 | } | |
5958 | ||
5959 | /* | |
5960 | * Sets up an aio uring context, and returns the fd. Applications asks for a | |
5961 | * ring size, we return the actual sq/cq ring sizes (among other things) in the | |
5962 | * params structure passed in. | |
5963 | */ | |
5964 | static long io_uring_setup(u32 entries, struct io_uring_params __user *params) | |
5965 | { | |
5966 | struct io_uring_params p; | |
5967 | long ret; | |
5968 | int i; | |
5969 | ||
5970 | if (copy_from_user(&p, params, sizeof(p))) | |
5971 | return -EFAULT; | |
5972 | for (i = 0; i < ARRAY_SIZE(p.resv); i++) { | |
5973 | if (p.resv[i]) | |
5974 | return -EINVAL; | |
5975 | } | |
5976 | ||
6c271ce2 | 5977 | if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL | |
33a107f0 | 5978 | IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE)) |
2b188cc1 JA |
5979 | return -EINVAL; |
5980 | ||
5981 | ret = io_uring_create(entries, &p); | |
5982 | if (ret < 0) | |
5983 | return ret; | |
5984 | ||
5985 | if (copy_to_user(params, &p, sizeof(p))) | |
5986 | return -EFAULT; | |
5987 | ||
5988 | return ret; | |
5989 | } | |
5990 | ||
5991 | SYSCALL_DEFINE2(io_uring_setup, u32, entries, | |
5992 | struct io_uring_params __user *, params) | |
5993 | { | |
5994 | return io_uring_setup(entries, params); | |
5995 | } | |
5996 | ||
edafccee JA |
5997 | static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, |
5998 | void __user *arg, unsigned nr_args) | |
b19062a5 JA |
5999 | __releases(ctx->uring_lock) |
6000 | __acquires(ctx->uring_lock) | |
edafccee JA |
6001 | { |
6002 | int ret; | |
6003 | ||
35fa71a0 JA |
6004 | /* |
6005 | * We're inside the ring mutex, if the ref is already dying, then | |
6006 | * someone else killed the ctx or is already going through | |
6007 | * io_uring_register(). | |
6008 | */ | |
6009 | if (percpu_ref_is_dying(&ctx->refs)) | |
6010 | return -ENXIO; | |
6011 | ||
05f3fb3c JA |
6012 | if (opcode != IORING_UNREGISTER_FILES && |
6013 | opcode != IORING_REGISTER_FILES_UPDATE) { | |
6014 | percpu_ref_kill(&ctx->refs); | |
b19062a5 | 6015 | |
05f3fb3c JA |
6016 | /* |
6017 | * Drop uring mutex before waiting for references to exit. If | |
6018 | * another thread is currently inside io_uring_enter() it might | |
6019 | * need to grab the uring_lock to make progress. If we hold it | |
6020 | * here across the drain wait, then we can deadlock. It's safe | |
6021 | * to drop the mutex here, since no new references will come in | |
6022 | * after we've killed the percpu ref. | |
6023 | */ | |
6024 | mutex_unlock(&ctx->uring_lock); | |
6025 | wait_for_completion(&ctx->completions[0]); | |
6026 | mutex_lock(&ctx->uring_lock); | |
6027 | } | |
edafccee JA |
6028 | |
6029 | switch (opcode) { | |
6030 | case IORING_REGISTER_BUFFERS: | |
6031 | ret = io_sqe_buffer_register(ctx, arg, nr_args); | |
6032 | break; | |
6033 | case IORING_UNREGISTER_BUFFERS: | |
6034 | ret = -EINVAL; | |
6035 | if (arg || nr_args) | |
6036 | break; | |
6037 | ret = io_sqe_buffer_unregister(ctx); | |
6038 | break; | |
6b06314c JA |
6039 | case IORING_REGISTER_FILES: |
6040 | ret = io_sqe_files_register(ctx, arg, nr_args); | |
6041 | break; | |
6042 | case IORING_UNREGISTER_FILES: | |
6043 | ret = -EINVAL; | |
6044 | if (arg || nr_args) | |
6045 | break; | |
6046 | ret = io_sqe_files_unregister(ctx); | |
6047 | break; | |
c3a31e60 JA |
6048 | case IORING_REGISTER_FILES_UPDATE: |
6049 | ret = io_sqe_files_update(ctx, arg, nr_args); | |
6050 | break; | |
9b402849 JA |
6051 | case IORING_REGISTER_EVENTFD: |
6052 | ret = -EINVAL; | |
6053 | if (nr_args != 1) | |
6054 | break; | |
6055 | ret = io_eventfd_register(ctx, arg); | |
6056 | break; | |
6057 | case IORING_UNREGISTER_EVENTFD: | |
6058 | ret = -EINVAL; | |
6059 | if (arg || nr_args) | |
6060 | break; | |
6061 | ret = io_eventfd_unregister(ctx); | |
6062 | break; | |
edafccee JA |
6063 | default: |
6064 | ret = -EINVAL; | |
6065 | break; | |
6066 | } | |
6067 | ||
05f3fb3c JA |
6068 | |
6069 | if (opcode != IORING_UNREGISTER_FILES && | |
6070 | opcode != IORING_REGISTER_FILES_UPDATE) { | |
6071 | /* bring the ctx back to life */ | |
6072 | reinit_completion(&ctx->completions[0]); | |
6073 | percpu_ref_reinit(&ctx->refs); | |
6074 | } | |
edafccee JA |
6075 | return ret; |
6076 | } | |
6077 | ||
6078 | SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode, | |
6079 | void __user *, arg, unsigned int, nr_args) | |
6080 | { | |
6081 | struct io_ring_ctx *ctx; | |
6082 | long ret = -EBADF; | |
6083 | struct fd f; | |
6084 | ||
6085 | f = fdget(fd); | |
6086 | if (!f.file) | |
6087 | return -EBADF; | |
6088 | ||
6089 | ret = -EOPNOTSUPP; | |
6090 | if (f.file->f_op != &io_uring_fops) | |
6091 | goto out_fput; | |
6092 | ||
6093 | ctx = f.file->private_data; | |
6094 | ||
6095 | mutex_lock(&ctx->uring_lock); | |
6096 | ret = __io_uring_register(ctx, opcode, arg, nr_args); | |
6097 | mutex_unlock(&ctx->uring_lock); | |
c826bd7a DD |
6098 | trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs, |
6099 | ctx->cq_ev_fd != NULL, ret); | |
edafccee JA |
6100 | out_fput: |
6101 | fdput(f); | |
6102 | return ret; | |
6103 | } | |
6104 | ||
2b188cc1 JA |
6105 | static int __init io_uring_init(void) |
6106 | { | |
6107 | req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC); | |
6108 | return 0; | |
6109 | }; | |
6110 | __initcall(io_uring_init); |