blob: 30d88f3d42b0dd645f6691c40a1531a2685538ca [file] [log] [blame]
Jens Axboe2b188cc2019-01-07 10:46:33 -07001// 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
Stefan Bühler1e84b972019-04-24 23:54:16 +02007 * 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.
Jens Axboe2b188cc2019-01-07 10:46:33 -070029 *
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
Christoph Hellwigc992fe22019-01-11 09:43:02 -070040 * Copyright (c) 2018-2019 Christoph Hellwig
Jens Axboe2b188cc2019-01-07 10:46:33 -070041 */
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>
Jens Axboe52de1fe2020-02-27 10:15:42 -070047#include <net/compat.h>
Jens Axboe2b188cc2019-01-07 10:46:33 -070048#include <linux/refcount.h>
49#include <linux/uio.h>
Pavel Begunkov6b47ee62020-01-18 20:22:41 +030050#include <linux/bits.h>
Jens Axboe2b188cc2019-01-07 10:46:33 -070051
52#include <linux/sched/signal.h>
53#include <linux/fs.h>
54#include <linux/file.h>
55#include <linux/fdtable.h>
56#include <linux/mm.h>
57#include <linux/mman.h>
Jens Axboe2b188cc2019-01-07 10:46:33 -070058#include <linux/percpu.h>
59#include <linux/slab.h>
Jens Axboe6c271ce2019-01-10 11:22:30 -070060#include <linux/kthread.h>
Jens Axboe2b188cc2019-01-07 10:46:33 -070061#include <linux/blkdev.h>
Jens Axboeedafcce2019-01-09 09:16:05 -070062#include <linux/bvec.h>
Jens Axboe2b188cc2019-01-07 10:46:33 -070063#include <linux/net.h>
64#include <net/sock.h>
65#include <net/af_unix.h>
Jens Axboe6b063142019-01-10 22:13:58 -070066#include <net/scm.h>
Jens Axboe2b188cc2019-01-07 10:46:33 -070067#include <linux/anon_inodes.h>
68#include <linux/sched/mm.h>
69#include <linux/uaccess.h>
70#include <linux/nospec.h>
Jens Axboeedafcce2019-01-09 09:16:05 -070071#include <linux/sizes.h>
72#include <linux/hugetlb.h>
Jens Axboeaa4c3962019-11-29 10:14:00 -070073#include <linux/highmem.h>
Jens Axboe15b71ab2019-12-11 11:20:36 -070074#include <linux/namei.h>
75#include <linux/fsnotify.h>
Jens Axboe4840e412019-12-25 22:03:45 -070076#include <linux/fadvise.h>
Jens Axboe3e4827b2020-01-08 15:18:09 -070077#include <linux/eventpoll.h>
Jens Axboeff002b32020-02-07 16:05:21 -070078#include <linux/fs_struct.h>
Pavel Begunkov7d67af22020-02-24 11:32:45 +030079#include <linux/splice.h>
Jens Axboeb41e9852020-02-17 09:52:41 -070080#include <linux/task_work.h>
Jens Axboebcf5a062020-05-22 09:24:42 -060081#include <linux/pagemap.h>
Jens Axboe0f212202020-09-13 13:09:39 -060082#include <linux/io_uring.h>
Dennis Zhou91d8f512020-09-16 13:41:05 -070083#include <linux/blk-cgroup.h>
Jens Axboe4ea33a92020-10-15 13:46:44 -060084#include <linux/audit.h>
Jens Axboe2b188cc2019-01-07 10:46:33 -070085
Dmitrii Dolgovc826bd72019-10-15 19:02:01 +020086#define CREATE_TRACE_POINTS
87#include <trace/events/io_uring.h>
88
Jens Axboe2b188cc2019-01-07 10:46:33 -070089#include <uapi/linux/io_uring.h>
90
91#include "internal.h"
Jens Axboe561fb042019-10-24 07:25:42 -060092#include "io-wq.h"
Jens Axboe2b188cc2019-01-07 10:46:33 -070093
Daniel Xu5277dea2019-09-14 14:23:45 -070094#define IORING_MAX_ENTRIES 32768
Jens Axboe33a107f2019-10-04 12:10:03 -060095#define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
Jens Axboe65e19f52019-10-26 07:20:21 -060096
97/*
98 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
99 */
100#define IORING_FILE_TABLE_SHIFT 9
101#define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
102#define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
103#define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
Stefano Garzarella21b55db2020-08-27 16:58:30 +0200104#define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
105 IORING_REGISTER_LAST + IORING_OP_LAST)
Jens Axboe2b188cc2019-01-07 10:46:33 -0700106
107struct io_uring {
108 u32 head ____cacheline_aligned_in_smp;
109 u32 tail ____cacheline_aligned_in_smp;
110};
111
Stefan Bühler1e84b972019-04-24 23:54:16 +0200112/*
Hristo Venev75b28af2019-08-26 17:23:46 +0000113 * This data is shared with the application through the mmap at offsets
114 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
Stefan Bühler1e84b972019-04-24 23:54:16 +0200115 *
116 * The offsets to the member fields are published through struct
117 * io_sqring_offsets when calling io_uring_setup.
118 */
Hristo Venev75b28af2019-08-26 17:23:46 +0000119struct io_rings {
Stefan Bühler1e84b972019-04-24 23:54:16 +0200120 /*
121 * Head and tail offsets into the ring; the offsets need to be
122 * masked to get valid indices.
123 *
Hristo Venev75b28af2019-08-26 17:23:46 +0000124 * The kernel controls head of the sq ring and the tail of the cq ring,
125 * and the application controls tail of the sq ring and the head of the
126 * cq ring.
Stefan Bühler1e84b972019-04-24 23:54:16 +0200127 */
Hristo Venev75b28af2019-08-26 17:23:46 +0000128 struct io_uring sq, cq;
Stefan Bühler1e84b972019-04-24 23:54:16 +0200129 /*
Hristo Venev75b28af2019-08-26 17:23:46 +0000130 * Bitmasks to apply to head and tail offsets (constant, equals
Stefan Bühler1e84b972019-04-24 23:54:16 +0200131 * ring_entries - 1)
132 */
Hristo Venev75b28af2019-08-26 17:23:46 +0000133 u32 sq_ring_mask, cq_ring_mask;
134 /* Ring sizes (constant, power of 2) */
135 u32 sq_ring_entries, cq_ring_entries;
Stefan Bühler1e84b972019-04-24 23:54:16 +0200136 /*
137 * Number of invalid entries dropped by the kernel due to
138 * invalid index stored in array
139 *
140 * Written by the kernel, shouldn't be modified by the
141 * application (i.e. get number of "new events" by comparing to
142 * cached value).
143 *
144 * After a new SQ head value was read by the application this
145 * counter includes all submissions that were dropped reaching
146 * the new SQ head (and possibly more).
147 */
Hristo Venev75b28af2019-08-26 17:23:46 +0000148 u32 sq_dropped;
Stefan Bühler1e84b972019-04-24 23:54:16 +0200149 /*
Stefano Garzarella0d9b5b32020-05-15 18:38:04 +0200150 * Runtime SQ flags
Stefan Bühler1e84b972019-04-24 23:54:16 +0200151 *
152 * Written by the kernel, shouldn't be modified by the
153 * application.
154 *
155 * The application needs a full memory barrier before checking
156 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
157 */
Hristo Venev75b28af2019-08-26 17:23:46 +0000158 u32 sq_flags;
Stefan Bühler1e84b972019-04-24 23:54:16 +0200159 /*
Stefano Garzarella0d9b5b32020-05-15 18:38:04 +0200160 * Runtime CQ flags
161 *
162 * Written by the application, shouldn't be modified by the
163 * kernel.
164 */
165 u32 cq_flags;
166 /*
Stefan Bühler1e84b972019-04-24 23:54:16 +0200167 * Number of completion events lost because the queue was full;
168 * this should be avoided by the application by making sure
LimingWu0b4295b2019-12-05 20:18:18 +0800169 * there are not more requests pending than there is space in
Stefan Bühler1e84b972019-04-24 23:54:16 +0200170 * the completion queue.
171 *
172 * Written by the kernel, shouldn't be modified by the
173 * application (i.e. get number of "new events" by comparing to
174 * cached value).
175 *
176 * As completion events come in out of order this counter is not
177 * ordered with any other data.
178 */
Hristo Venev75b28af2019-08-26 17:23:46 +0000179 u32 cq_overflow;
Stefan Bühler1e84b972019-04-24 23:54:16 +0200180 /*
181 * Ring buffer of completion events.
182 *
183 * The kernel writes completion events fresh every time they are
184 * produced, so the application is allowed to modify pending
185 * entries.
186 */
Hristo Venev75b28af2019-08-26 17:23:46 +0000187 struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700188};
189
Jens Axboeedafcce2019-01-09 09:16:05 -0700190struct io_mapped_ubuf {
191 u64 ubuf;
192 size_t len;
193 struct bio_vec *bvec;
194 unsigned int nr_bvecs;
Jens Axboede293932020-09-17 16:19:16 -0600195 unsigned long acct_pages;
Jens Axboeedafcce2019-01-09 09:16:05 -0700196};
197
Jens Axboe65e19f52019-10-26 07:20:21 -0600198struct fixed_file_table {
199 struct file **files;
Jens Axboe31b51512019-01-18 22:56:34 -0700200};
201
Xiaoguang Wang05589552020-03-31 14:05:18 +0800202struct fixed_file_ref_node {
203 struct percpu_ref refs;
204 struct list_head node;
205 struct list_head file_list;
206 struct fixed_file_data *file_data;
Jens Axboe4a38aed22020-05-14 17:21:15 -0600207 struct llist_node llist;
Xiaoguang Wang05589552020-03-31 14:05:18 +0800208};
209
Jens Axboe05f3fb32019-12-09 11:22:50 -0700210struct fixed_file_data {
211 struct fixed_file_table *table;
212 struct io_ring_ctx *ctx;
213
Pavel Begunkovb2e96852020-10-10 18:34:16 +0100214 struct fixed_file_ref_node *node;
Jens Axboe05f3fb32019-12-09 11:22:50 -0700215 struct percpu_ref refs;
Jens Axboe05f3fb32019-12-09 11:22:50 -0700216 struct completion done;
Xiaoguang Wang05589552020-03-31 14:05:18 +0800217 struct list_head ref_list;
218 spinlock_t lock;
Jens Axboe05f3fb32019-12-09 11:22:50 -0700219};
220
Jens Axboe5a2e7452020-02-23 16:23:11 -0700221struct io_buffer {
222 struct list_head list;
223 __u64 addr;
224 __s32 len;
225 __u16 bid;
226};
227
Stefano Garzarella21b55db2020-08-27 16:58:30 +0200228struct io_restriction {
229 DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
230 DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
231 u8 sqe_flags_allowed;
232 u8 sqe_flags_required;
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +0200233 bool registered;
Stefano Garzarella21b55db2020-08-27 16:58:30 +0200234};
235
Jens Axboe534ca6d2020-09-02 13:52:19 -0600236struct io_sq_data {
237 refcount_t refs;
Jens Axboe69fb2132020-09-14 11:16:23 -0600238 struct mutex lock;
239
240 /* ctx's that are using this sqd */
241 struct list_head ctx_list;
242 struct list_head ctx_new_list;
243 struct mutex ctx_lock;
244
Jens Axboe534ca6d2020-09-02 13:52:19 -0600245 struct task_struct *thread;
246 struct wait_queue_head wait;
247};
248
Jens Axboe2b188cc2019-01-07 10:46:33 -0700249struct io_ring_ctx {
250 struct {
251 struct percpu_ref refs;
252 } ____cacheline_aligned_in_smp;
253
254 struct {
255 unsigned int flags;
Randy Dunlape1d85332020-02-05 20:57:10 -0800256 unsigned int compat: 1;
Bijan Mottahedehaad5d8d2020-06-16 16:36:08 -0700257 unsigned int limit_mem: 1;
Randy Dunlape1d85332020-02-05 20:57:10 -0800258 unsigned int cq_overflow_flushed: 1;
259 unsigned int drain_next: 1;
260 unsigned int eventfd_async: 1;
Stefano Garzarella21b55db2020-08-27 16:58:30 +0200261 unsigned int restricted: 1;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700262
Hristo Venev75b28af2019-08-26 17:23:46 +0000263 /*
264 * Ring buffer of indices into array of io_uring_sqe, which is
265 * mmapped by the application using the IORING_OFF_SQES offset.
266 *
267 * This indirection could e.g. be used to assign fixed
268 * io_uring_sqe entries to operations and only submit them to
269 * the queue when needed.
270 *
271 * The kernel modifies neither the indices array nor the entries
272 * array.
273 */
274 u32 *sq_array;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700275 unsigned cached_sq_head;
276 unsigned sq_entries;
277 unsigned sq_mask;
Jens Axboe6c271ce2019-01-10 11:22:30 -0700278 unsigned sq_thread_idle;
Jens Axboe498ccd92019-10-25 10:04:25 -0600279 unsigned cached_sq_dropped;
Pavel Begunkov2c3bac6d2020-10-18 10:17:40 +0100280 unsigned cached_cq_overflow;
Jens Axboead3eb2c2019-12-18 17:12:20 -0700281 unsigned long sq_check_overflow;
Jens Axboede0617e2019-04-06 21:51:27 -0600282
283 struct list_head defer_list;
Jens Axboe5262f562019-09-17 12:26:57 -0600284 struct list_head timeout_list;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -0700285 struct list_head cq_overflow_list;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700286
Jens Axboefcb323c2019-10-24 12:39:47 -0600287 wait_queue_head_t inflight_wait;
Jens Axboead3eb2c2019-12-18 17:12:20 -0700288 struct io_uring_sqe *sq_sqes;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700289 } ____cacheline_aligned_in_smp;
290
Hristo Venev75b28af2019-08-26 17:23:46 +0000291 struct io_rings *rings;
292
Jens Axboe2b188cc2019-01-07 10:46:33 -0700293 /* IO offload */
Jens Axboe561fb042019-10-24 07:25:42 -0600294 struct io_wq *io_wq;
Jens Axboe2aede0e2020-09-14 10:45:53 -0600295
296 /*
297 * For SQPOLL usage - we hold a reference to the parent task, so we
298 * have access to the ->files
299 */
300 struct task_struct *sqo_task;
301
302 /* Only used for accounting purposes */
303 struct mm_struct *mm_account;
304
Dennis Zhou91d8f512020-09-16 13:41:05 -0700305#ifdef CONFIG_BLK_CGROUP
306 struct cgroup_subsys_state *sqo_blkcg_css;
307#endif
308
Jens Axboe534ca6d2020-09-02 13:52:19 -0600309 struct io_sq_data *sq_data; /* if using sq thread polling */
310
Jens Axboe90554202020-09-03 12:12:41 -0600311 struct wait_queue_head sqo_sq_wait;
Jens Axboe6a779382020-09-02 12:21:41 -0600312 struct wait_queue_entry sqo_wait_entry;
Jens Axboe69fb2132020-09-14 11:16:23 -0600313 struct list_head sqd_list;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700314
Jens Axboe6b063142019-01-10 22:13:58 -0700315 /*
316 * If used, fixed file set. Writers must ensure that ->refs is dead,
317 * readers must ensure that ->refs is alive as long as the file* is
318 * used. Only updated through io_uring_register(2).
319 */
Jens Axboe05f3fb32019-12-09 11:22:50 -0700320 struct fixed_file_data *file_data;
Jens Axboe6b063142019-01-10 22:13:58 -0700321 unsigned nr_user_files;
322
Jens Axboeedafcce2019-01-09 09:16:05 -0700323 /* if used, fixed mapped user buffers */
324 unsigned nr_user_bufs;
325 struct io_mapped_ubuf *user_bufs;
326
Jens Axboe2b188cc2019-01-07 10:46:33 -0700327 struct user_struct *user;
328
Jens Axboe0b8c0ec2019-12-02 08:50:00 -0700329 const struct cred *creds;
Jens Axboe181e4482019-11-25 08:52:30 -0700330
Jens Axboe4ea33a92020-10-15 13:46:44 -0600331#ifdef CONFIG_AUDIT
332 kuid_t loginuid;
333 unsigned int sessionid;
334#endif
335
Jens Axboe0f158b42020-05-14 17:18:39 -0600336 struct completion ref_comp;
337 struct completion sq_thread_comp;
Jens Axboe206aefd2019-11-07 18:27:42 -0700338
Jens Axboe0ddf92e2019-11-08 08:52:53 -0700339 /* if all else fails... */
340 struct io_kiocb *fallback_req;
341
Jens Axboe206aefd2019-11-07 18:27:42 -0700342#if defined(CONFIG_UNIX)
343 struct socket *ring_sock;
344#endif
345
Jens Axboe5a2e7452020-02-23 16:23:11 -0700346 struct idr io_buffer_idr;
347
Jens Axboe071698e2020-01-28 10:04:42 -0700348 struct idr personality_idr;
349
Jens Axboe206aefd2019-11-07 18:27:42 -0700350 struct {
351 unsigned cached_cq_tail;
352 unsigned cq_entries;
353 unsigned cq_mask;
354 atomic_t cq_timeouts;
Jens Axboead3eb2c2019-12-18 17:12:20 -0700355 unsigned long cq_check_overflow;
Jens Axboe206aefd2019-11-07 18:27:42 -0700356 struct wait_queue_head cq_wait;
357 struct fasync_struct *cq_fasync;
358 struct eventfd_ctx *cq_ev_fd;
359 } ____cacheline_aligned_in_smp;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700360
361 struct {
362 struct mutex uring_lock;
363 wait_queue_head_t wait;
364 } ____cacheline_aligned_in_smp;
365
366 struct {
367 spinlock_t completion_lock;
Jens Axboee94f1412019-12-19 12:06:02 -0700368
Jens Axboedef596e2019-01-09 08:59:42 -0700369 /*
Pavel Begunkov540e32a2020-07-13 23:37:09 +0300370 * ->iopoll_list is protected by the ctx->uring_lock for
Jens Axboedef596e2019-01-09 08:59:42 -0700371 * io_uring instances that don't use IORING_SETUP_SQPOLL.
372 * For SQPOLL, only the single threaded io_sq_thread() will
373 * manipulate the list, hence no extra locking is needed there.
374 */
Pavel Begunkov540e32a2020-07-13 23:37:09 +0300375 struct list_head iopoll_list;
Jens Axboe78076bb2019-12-04 19:56:40 -0700376 struct hlist_head *cancel_hash;
377 unsigned cancel_hash_bits;
Jens Axboee94f1412019-12-19 12:06:02 -0700378 bool poll_multi_file;
Jens Axboefcb323c2019-10-24 12:39:47 -0600379
380 spinlock_t inflight_lock;
381 struct list_head inflight_list;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700382 } ____cacheline_aligned_in_smp;
Jens Axboe85faa7b2020-04-09 18:14:00 -0600383
Jens Axboe4a38aed22020-05-14 17:21:15 -0600384 struct delayed_work file_put_work;
385 struct llist_head file_put_llist;
386
Jens Axboe85faa7b2020-04-09 18:14:00 -0600387 struct work_struct exit_work;
Stefano Garzarella21b55db2020-08-27 16:58:30 +0200388 struct io_restriction restrictions;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700389};
390
Jens Axboe09bb8392019-03-13 12:39:28 -0600391/*
392 * First field must be the file pointer in all the
393 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
394 */
Jens Axboe221c5eb2019-01-17 09:41:58 -0700395struct io_poll_iocb {
396 struct file *file;
Jens Axboe0969e782019-12-17 18:40:57 -0700397 union {
398 struct wait_queue_head *head;
399 u64 addr;
400 };
Jens Axboe221c5eb2019-01-17 09:41:58 -0700401 __poll_t events;
Jens Axboe8c838782019-03-12 15:48:16 -0600402 bool done;
Jens Axboe221c5eb2019-01-17 09:41:58 -0700403 bool canceled;
Jens Axboe392edb42019-12-09 17:52:20 -0700404 struct wait_queue_entry wait;
Jens Axboe221c5eb2019-01-17 09:41:58 -0700405};
406
Jens Axboeb5dba592019-12-11 14:02:38 -0700407struct io_close {
408 struct file *file;
409 struct file *put_file;
410 int fd;
411};
412
Jens Axboead8a48a2019-11-15 08:49:11 -0700413struct io_timeout_data {
414 struct io_kiocb *req;
415 struct hrtimer timer;
416 struct timespec64 ts;
417 enum hrtimer_mode mode;
418};
419
Jens Axboe8ed8d3c2019-12-16 11:55:28 -0700420struct io_accept {
421 struct file *file;
422 struct sockaddr __user *addr;
423 int __user *addr_len;
424 int flags;
Jens Axboe09952e32020-03-19 20:16:56 -0600425 unsigned long nofile;
Jens Axboe8ed8d3c2019-12-16 11:55:28 -0700426};
427
428struct io_sync {
429 struct file *file;
430 loff_t len;
431 loff_t off;
432 int flags;
Jens Axboed63d1b52019-12-10 10:38:56 -0700433 int mode;
Jens Axboe8ed8d3c2019-12-16 11:55:28 -0700434};
435
Jens Axboefbf23842019-12-17 18:45:56 -0700436struct io_cancel {
437 struct file *file;
438 u64 addr;
439};
440
Jens Axboeb29472e2019-12-17 18:50:29 -0700441struct io_timeout {
442 struct file *file;
Pavel Begunkovbfe68a22020-05-30 14:54:18 +0300443 u32 off;
444 u32 target_seq;
Pavel Begunkov135fcde2020-07-13 23:37:12 +0300445 struct list_head list;
Jens Axboeb29472e2019-12-17 18:50:29 -0700446};
447
Pavel Begunkov0bdf7a22020-10-10 18:34:10 +0100448struct io_timeout_rem {
449 struct file *file;
450 u64 addr;
451};
452
Jens Axboe9adbd452019-12-20 08:45:55 -0700453struct io_rw {
454 /* NOTE: kiocb has the file as the first member, so don't do it here */
455 struct kiocb kiocb;
456 u64 addr;
457 u64 len;
458};
459
Jens Axboe3fbb51c2019-12-20 08:51:52 -0700460struct io_connect {
461 struct file *file;
462 struct sockaddr __user *addr;
463 int addr_len;
464};
465
Jens Axboee47293f2019-12-20 08:58:21 -0700466struct io_sr_msg {
467 struct file *file;
Jens Axboefddafac2020-01-04 20:19:44 -0700468 union {
Pavel Begunkov270a5942020-07-12 20:41:04 +0300469 struct user_msghdr __user *umsg;
Jens Axboefddafac2020-01-04 20:19:44 -0700470 void __user *buf;
471 };
Jens Axboee47293f2019-12-20 08:58:21 -0700472 int msg_flags;
Jens Axboebcda7ba2020-02-23 16:42:51 -0700473 int bgid;
Jens Axboefddafac2020-01-04 20:19:44 -0700474 size_t len;
Jens Axboebcda7ba2020-02-23 16:42:51 -0700475 struct io_buffer *kbuf;
Jens Axboee47293f2019-12-20 08:58:21 -0700476};
477
Jens Axboe15b71ab2019-12-11 11:20:36 -0700478struct io_open {
479 struct file *file;
480 int dfd;
Jens Axboe15b71ab2019-12-11 11:20:36 -0700481 struct filename *filename;
Jens Axboec12cedf2020-01-08 17:41:21 -0700482 struct open_how how;
Jens Axboe4022e7a2020-03-19 19:23:18 -0600483 unsigned long nofile;
Jens Axboe15b71ab2019-12-11 11:20:36 -0700484};
485
Jens Axboe05f3fb32019-12-09 11:22:50 -0700486struct io_files_update {
487 struct file *file;
488 u64 arg;
489 u32 nr_args;
490 u32 offset;
491};
492
Jens Axboe4840e412019-12-25 22:03:45 -0700493struct io_fadvise {
494 struct file *file;
495 u64 offset;
496 u32 len;
497 u32 advice;
498};
499
Jens Axboec1ca7572019-12-25 22:18:28 -0700500struct io_madvise {
501 struct file *file;
502 u64 addr;
503 u32 len;
504 u32 advice;
505};
506
Jens Axboe3e4827b2020-01-08 15:18:09 -0700507struct io_epoll {
508 struct file *file;
509 int epfd;
510 int op;
511 int fd;
512 struct epoll_event event;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700513};
514
Pavel Begunkov7d67af22020-02-24 11:32:45 +0300515struct io_splice {
516 struct file *file_out;
517 struct file *file_in;
518 loff_t off_out;
519 loff_t off_in;
520 u64 len;
521 unsigned int flags;
522};
523
Jens Axboeddf0322d2020-02-23 16:41:33 -0700524struct io_provide_buf {
525 struct file *file;
526 __u64 addr;
527 __s32 len;
528 __u32 bgid;
529 __u16 nbufs;
530 __u16 bid;
531};
532
Bijan Mottahedeh1d9e1282020-05-22 21:31:16 -0700533struct io_statx {
534 struct file *file;
535 int dfd;
536 unsigned int mask;
537 unsigned int flags;
Bijan Mottahedehe62753e2020-05-22 21:31:18 -0700538 const char __user *filename;
Bijan Mottahedeh1d9e1282020-05-22 21:31:16 -0700539 struct statx __user *buffer;
540};
541
Pavel Begunkov3ca405e2020-07-13 23:37:08 +0300542struct io_completion {
543 struct file *file;
544 struct list_head list;
Pavel Begunkov0f7e4662020-07-13 23:37:16 +0300545 int cflags;
Pavel Begunkov3ca405e2020-07-13 23:37:08 +0300546};
547
Jens Axboef499a022019-12-02 16:28:46 -0700548struct io_async_connect {
549 struct sockaddr_storage address;
550};
551
Jens Axboe03b12302019-12-02 18:50:25 -0700552struct io_async_msghdr {
553 struct iovec fast_iov[UIO_FASTIOV];
554 struct iovec *iov;
555 struct sockaddr __user *uaddr;
556 struct msghdr msg;
Jens Axboeb5379162020-02-09 11:29:15 -0700557 struct sockaddr_storage addr;
Jens Axboe03b12302019-12-02 18:50:25 -0700558};
559
Jens Axboef67676d2019-12-02 11:03:47 -0700560struct io_async_rw {
561 struct iovec fast_iov[UIO_FASTIOV];
Jens Axboeff6165b2020-08-13 09:47:43 -0600562 const struct iovec *free_iovec;
563 struct iov_iter iter;
Jens Axboe227c0c92020-08-13 11:51:40 -0600564 size_t bytes_done;
Jens Axboebcf5a062020-05-22 09:24:42 -0600565 struct wait_page_queue wpq;
Jens Axboef67676d2019-12-02 11:03:47 -0700566};
567
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300568enum {
569 REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
570 REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
571 REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
572 REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
573 REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
Jens Axboebcda7ba2020-02-23 16:42:51 -0700574 REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300575
Pavel Begunkovdea3b492020-04-12 02:05:04 +0300576 REQ_F_LINK_HEAD_BIT,
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300577 REQ_F_FAIL_LINK_BIT,
578 REQ_F_INFLIGHT_BIT,
579 REQ_F_CUR_POS_BIT,
580 REQ_F_NOWAIT_BIT,
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300581 REQ_F_LINK_TIMEOUT_BIT,
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300582 REQ_F_ISREG_BIT,
Pavel Begunkov99bc4c32020-02-07 22:04:45 +0300583 REQ_F_NEED_CLEANUP_BIT,
Jens Axboed7718a92020-02-14 22:23:12 -0700584 REQ_F_POLLED_BIT,
Jens Axboebcda7ba2020-02-23 16:42:51 -0700585 REQ_F_BUFFER_SELECTED_BIT,
Jens Axboe5b0bbee2020-04-27 10:41:22 -0600586 REQ_F_NO_FILE_TABLE_BIT,
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +0800587 REQ_F_WORK_INITIALIZED_BIT,
Pavel Begunkov900fad42020-10-19 16:39:16 +0100588 REQ_F_LTIMEOUT_ACTIVE_BIT,
Jens Axboe84557872020-03-03 15:28:17 -0700589
590 /* not a real bit, just to check we're not overflowing the space */
591 __REQ_F_LAST_BIT,
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300592};
593
594enum {
595 /* ctx owns file */
596 REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
597 /* drain existing IO first */
598 REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
599 /* linked sqes */
600 REQ_F_LINK = BIT(REQ_F_LINK_BIT),
601 /* doesn't sever on completion < 0 */
602 REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
603 /* IOSQE_ASYNC */
604 REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
Jens Axboebcda7ba2020-02-23 16:42:51 -0700605 /* IOSQE_BUFFER_SELECT */
606 REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300607
Pavel Begunkovdea3b492020-04-12 02:05:04 +0300608 /* head of a link */
609 REQ_F_LINK_HEAD = BIT(REQ_F_LINK_HEAD_BIT),
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300610 /* fail rest of links */
611 REQ_F_FAIL_LINK = BIT(REQ_F_FAIL_LINK_BIT),
612 /* on inflight list */
613 REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
614 /* read/write uses file position */
615 REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
616 /* must not punt to workers */
617 REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
Pavel Begunkov900fad42020-10-19 16:39:16 +0100618 /* has or had linked timeout */
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300619 REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300620 /* regular file */
621 REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
Pavel Begunkov99bc4c32020-02-07 22:04:45 +0300622 /* needs cleanup */
623 REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
Jens Axboed7718a92020-02-14 22:23:12 -0700624 /* already went through poll handler */
625 REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
Jens Axboebcda7ba2020-02-23 16:42:51 -0700626 /* buffer already selected */
627 REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
Jens Axboe5b0bbee2020-04-27 10:41:22 -0600628 /* doesn't need file table for this request */
629 REQ_F_NO_FILE_TABLE = BIT(REQ_F_NO_FILE_TABLE_BIT),
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +0800630 /* io_wq_work is initialized */
631 REQ_F_WORK_INITIALIZED = BIT(REQ_F_WORK_INITIALIZED_BIT),
Pavel Begunkov900fad42020-10-19 16:39:16 +0100632 /* linked timeout is active, i.e. prepared by link's head */
633 REQ_F_LTIMEOUT_ACTIVE = BIT(REQ_F_LTIMEOUT_ACTIVE_BIT),
Jens Axboed7718a92020-02-14 22:23:12 -0700634};
635
636struct async_poll {
637 struct io_poll_iocb poll;
Jens Axboe807abcb2020-07-17 17:09:27 -0600638 struct io_poll_iocb *double_poll;
Pavel Begunkov6b47ee62020-01-18 20:22:41 +0300639};
640
Jens Axboe09bb8392019-03-13 12:39:28 -0600641/*
642 * NOTE! Each of the iocb union members has the file pointer
643 * as the first entry in their struct definition. So you can
644 * access the file pointer through any of the sub-structs,
645 * or directly as just 'ki_filp' in this struct.
646 */
Jens Axboe2b188cc2019-01-07 10:46:33 -0700647struct io_kiocb {
Jens Axboe221c5eb2019-01-17 09:41:58 -0700648 union {
Jens Axboe09bb8392019-03-13 12:39:28 -0600649 struct file *file;
Jens Axboe9adbd452019-12-20 08:45:55 -0700650 struct io_rw rw;
Jens Axboe221c5eb2019-01-17 09:41:58 -0700651 struct io_poll_iocb poll;
Jens Axboe8ed8d3c2019-12-16 11:55:28 -0700652 struct io_accept accept;
653 struct io_sync sync;
Jens Axboefbf23842019-12-17 18:45:56 -0700654 struct io_cancel cancel;
Jens Axboeb29472e2019-12-17 18:50:29 -0700655 struct io_timeout timeout;
Pavel Begunkov0bdf7a22020-10-10 18:34:10 +0100656 struct io_timeout_rem timeout_rem;
Jens Axboe3fbb51c2019-12-20 08:51:52 -0700657 struct io_connect connect;
Jens Axboee47293f2019-12-20 08:58:21 -0700658 struct io_sr_msg sr_msg;
Jens Axboe15b71ab2019-12-11 11:20:36 -0700659 struct io_open open;
Jens Axboeb5dba592019-12-11 14:02:38 -0700660 struct io_close close;
Jens Axboe05f3fb32019-12-09 11:22:50 -0700661 struct io_files_update files_update;
Jens Axboe4840e412019-12-25 22:03:45 -0700662 struct io_fadvise fadvise;
Jens Axboec1ca7572019-12-25 22:18:28 -0700663 struct io_madvise madvise;
Jens Axboe3e4827b2020-01-08 15:18:09 -0700664 struct io_epoll epoll;
Pavel Begunkov7d67af22020-02-24 11:32:45 +0300665 struct io_splice splice;
Jens Axboeddf0322d2020-02-23 16:41:33 -0700666 struct io_provide_buf pbuf;
Bijan Mottahedeh1d9e1282020-05-22 21:31:16 -0700667 struct io_statx statx;
Pavel Begunkov3ca405e2020-07-13 23:37:08 +0300668 /* use only after cleaning per-op data, see io_clean_op() */
669 struct io_completion compl;
Jens Axboe221c5eb2019-01-17 09:41:58 -0700670 };
Jens Axboe2b188cc2019-01-07 10:46:33 -0700671
Jens Axboee8c2bc12020-08-15 18:44:09 -0700672 /* opcode allocated if it needs to store data for async defer */
673 void *async_data;
Jens Axboed625c6e2019-12-17 19:53:05 -0700674 u8 opcode;
Xiaoguang Wang65a65432020-06-11 23:39:36 +0800675 /* polled IO has completed */
676 u8 iopoll_completed;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700677
Bijan Mottahedeh4f4eeba2020-05-19 14:52:49 -0700678 u16 buf_index;
Pavel Begunkov9cf7c102020-07-13 23:37:15 +0300679 u32 result;
Bijan Mottahedeh4f4eeba2020-05-19 14:52:49 -0700680
Pavel Begunkov010e8e62020-07-30 18:43:45 +0300681 struct io_ring_ctx *ctx;
682 unsigned int flags;
683 refcount_t refs;
684 struct task_struct *task;
685 u64 user_data;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700686
Pavel Begunkov010e8e62020-07-30 18:43:45 +0300687 struct list_head link_list;
Jens Axboed7718a92020-02-14 22:23:12 -0700688
Pavel Begunkovd21ffe72020-07-13 23:37:10 +0300689 /*
690 * 1. used with ctx->iopoll_list with reads/writes
691 * 2. to track reqs with ->files (see io_op_def::file_table)
692 */
Pavel Begunkov010e8e62020-07-30 18:43:45 +0300693 struct list_head inflight_entry;
Jens Axboefcb323c2019-10-24 12:39:47 -0600694
Pavel Begunkov010e8e62020-07-30 18:43:45 +0300695 struct percpu_ref *fixed_file_refs;
696 struct callback_head task_work;
697 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
698 struct hlist_node hash_node;
699 struct async_poll *apoll;
700 struct io_wq_work work;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700701};
702
Pavel Begunkov27dc8332020-07-13 23:37:14 +0300703struct io_defer_entry {
704 struct list_head list;
705 struct io_kiocb *req;
Pavel Begunkov9cf7c102020-07-13 23:37:15 +0300706 u32 seq;
Pavel Begunkov27dc8332020-07-13 23:37:14 +0300707};
708
Jens Axboedef596e2019-01-09 08:59:42 -0700709#define IO_IOPOLL_BATCH 8
Jens Axboe2b188cc2019-01-07 10:46:33 -0700710
Jens Axboe013538b2020-06-22 09:29:15 -0600711struct io_comp_state {
712 unsigned int nr;
713 struct list_head list;
714 struct io_ring_ctx *ctx;
715};
716
Jens Axboe9a56a232019-01-09 09:06:50 -0700717struct io_submit_state {
718 struct blk_plug plug;
719
720 /*
Jens Axboe2579f912019-01-09 09:10:43 -0700721 * io_kiocb alloc cache
722 */
723 void *reqs[IO_IOPOLL_BATCH];
Pavel Begunkov6c8a3132020-02-01 03:58:00 +0300724 unsigned int free_reqs;
Jens Axboe2579f912019-01-09 09:10:43 -0700725
726 /*
Jens Axboe013538b2020-06-22 09:29:15 -0600727 * Batch completion logic
728 */
729 struct io_comp_state comp;
730
731 /*
Jens Axboe9a56a232019-01-09 09:06:50 -0700732 * File reference cache
733 */
734 struct file *file;
735 unsigned int fd;
736 unsigned int has_refs;
Jens Axboe9a56a232019-01-09 09:06:50 -0700737 unsigned int ios_left;
738};
739
Jens Axboed3656342019-12-18 09:50:26 -0700740struct io_op_def {
Jens Axboed3656342019-12-18 09:50:26 -0700741 /* needs req->file assigned */
742 unsigned needs_file : 1;
Jens Axboefd2206e2020-06-02 16:40:47 -0600743 /* don't fail if file grab fails */
744 unsigned needs_file_no_error : 1;
Jens Axboed3656342019-12-18 09:50:26 -0700745 /* hash wq insertion if file is a regular file */
746 unsigned hash_reg_file : 1;
747 /* unbound wq insertion if file is a non-regular file */
748 unsigned unbound_nonreg_file : 1;
Jens Axboe66f4af92020-01-16 15:36:52 -0700749 /* opcode is not supported by this kernel */
750 unsigned not_supported : 1;
Jens Axboe8a727582020-02-20 09:59:44 -0700751 /* set if opcode supports polled "wait" */
752 unsigned pollin : 1;
753 unsigned pollout : 1;
Jens Axboebcda7ba2020-02-23 16:42:51 -0700754 /* op supports buffer selection */
755 unsigned buffer_select : 1;
Jens Axboee8c2bc12020-08-15 18:44:09 -0700756 /* must always have async data allocated */
757 unsigned needs_async_data : 1;
758 /* size of async data needed, if any */
759 unsigned short async_size;
Jens Axboe0f203762020-10-14 09:23:55 -0600760 unsigned work_flags;
Jens Axboed3656342019-12-18 09:50:26 -0700761};
762
Jens Axboe09186822020-10-13 15:01:40 -0600763static const struct io_op_def io_op_defs[] = {
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300764 [IORING_OP_NOP] = {},
765 [IORING_OP_READV] = {
Jens Axboed3656342019-12-18 09:50:26 -0700766 .needs_file = 1,
767 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700768 .pollin = 1,
Jens Axboe4d954c22020-02-27 07:31:19 -0700769 .buffer_select = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700770 .needs_async_data = 1,
771 .async_size = sizeof(struct io_async_rw),
Jens Axboe0f203762020-10-14 09:23:55 -0600772 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
Jens Axboed3656342019-12-18 09:50:26 -0700773 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300774 [IORING_OP_WRITEV] = {
Jens Axboed3656342019-12-18 09:50:26 -0700775 .needs_file = 1,
776 .hash_reg_file = 1,
777 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700778 .pollout = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700779 .needs_async_data = 1,
780 .async_size = sizeof(struct io_async_rw),
Jens Axboe69228332020-10-20 14:28:41 -0600781 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG |
782 IO_WQ_WORK_FSIZE,
Jens Axboed3656342019-12-18 09:50:26 -0700783 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300784 [IORING_OP_FSYNC] = {
Jens Axboed3656342019-12-18 09:50:26 -0700785 .needs_file = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600786 .work_flags = IO_WQ_WORK_BLKCG,
Jens Axboed3656342019-12-18 09:50:26 -0700787 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300788 [IORING_OP_READ_FIXED] = {
Jens Axboed3656342019-12-18 09:50:26 -0700789 .needs_file = 1,
790 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700791 .pollin = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700792 .async_size = sizeof(struct io_async_rw),
Jens Axboe4017eb92020-10-22 14:14:12 -0600793 .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_MM,
Jens Axboed3656342019-12-18 09:50:26 -0700794 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300795 [IORING_OP_WRITE_FIXED] = {
Jens Axboed3656342019-12-18 09:50:26 -0700796 .needs_file = 1,
797 .hash_reg_file = 1,
798 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700799 .pollout = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700800 .async_size = sizeof(struct io_async_rw),
Jens Axboe4017eb92020-10-22 14:14:12 -0600801 .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_FSIZE |
802 IO_WQ_WORK_MM,
Jens Axboed3656342019-12-18 09:50:26 -0700803 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300804 [IORING_OP_POLL_ADD] = {
Jens Axboed3656342019-12-18 09:50:26 -0700805 .needs_file = 1,
806 .unbound_nonreg_file = 1,
807 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300808 [IORING_OP_POLL_REMOVE] = {},
809 [IORING_OP_SYNC_FILE_RANGE] = {
Jens Axboed3656342019-12-18 09:50:26 -0700810 .needs_file = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600811 .work_flags = IO_WQ_WORK_BLKCG,
Jens Axboed3656342019-12-18 09:50:26 -0700812 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300813 [IORING_OP_SENDMSG] = {
Jens Axboed3656342019-12-18 09:50:26 -0700814 .needs_file = 1,
815 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700816 .pollout = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700817 .needs_async_data = 1,
818 .async_size = sizeof(struct io_async_msghdr),
Jens Axboe0f203762020-10-14 09:23:55 -0600819 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG |
820 IO_WQ_WORK_FS,
Jens Axboed3656342019-12-18 09:50:26 -0700821 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300822 [IORING_OP_RECVMSG] = {
Jens Axboed3656342019-12-18 09:50:26 -0700823 .needs_file = 1,
824 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700825 .pollin = 1,
Jens Axboe52de1fe2020-02-27 10:15:42 -0700826 .buffer_select = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700827 .needs_async_data = 1,
828 .async_size = sizeof(struct io_async_msghdr),
Jens Axboe0f203762020-10-14 09:23:55 -0600829 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG |
830 IO_WQ_WORK_FS,
Jens Axboed3656342019-12-18 09:50:26 -0700831 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300832 [IORING_OP_TIMEOUT] = {
Jens Axboee8c2bc12020-08-15 18:44:09 -0700833 .needs_async_data = 1,
834 .async_size = sizeof(struct io_timeout_data),
Jens Axboe0f203762020-10-14 09:23:55 -0600835 .work_flags = IO_WQ_WORK_MM,
Jens Axboed3656342019-12-18 09:50:26 -0700836 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300837 [IORING_OP_TIMEOUT_REMOVE] = {},
838 [IORING_OP_ACCEPT] = {
Jens Axboed3656342019-12-18 09:50:26 -0700839 .needs_file = 1,
840 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700841 .pollin = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600842 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_FILES,
Jens Axboed3656342019-12-18 09:50:26 -0700843 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300844 [IORING_OP_ASYNC_CANCEL] = {},
845 [IORING_OP_LINK_TIMEOUT] = {
Jens Axboee8c2bc12020-08-15 18:44:09 -0700846 .needs_async_data = 1,
847 .async_size = sizeof(struct io_timeout_data),
Jens Axboe0f203762020-10-14 09:23:55 -0600848 .work_flags = IO_WQ_WORK_MM,
Jens Axboed3656342019-12-18 09:50:26 -0700849 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300850 [IORING_OP_CONNECT] = {
Jens Axboed3656342019-12-18 09:50:26 -0700851 .needs_file = 1,
852 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700853 .pollout = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700854 .needs_async_data = 1,
855 .async_size = sizeof(struct io_async_connect),
Jens Axboe0f203762020-10-14 09:23:55 -0600856 .work_flags = IO_WQ_WORK_MM,
Jens Axboed3656342019-12-18 09:50:26 -0700857 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300858 [IORING_OP_FALLOCATE] = {
Jens Axboed3656342019-12-18 09:50:26 -0700859 .needs_file = 1,
Jens Axboe69228332020-10-20 14:28:41 -0600860 .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_FSIZE,
Jens Axboed3656342019-12-18 09:50:26 -0700861 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300862 [IORING_OP_OPENAT] = {
Jens Axboe0f203762020-10-14 09:23:55 -0600863 .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_BLKCG |
864 IO_WQ_WORK_FS,
Jens Axboed3656342019-12-18 09:50:26 -0700865 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300866 [IORING_OP_CLOSE] = {
Jens Axboefd2206e2020-06-02 16:40:47 -0600867 .needs_file = 1,
868 .needs_file_no_error = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600869 .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_BLKCG,
Jens Axboed3656342019-12-18 09:50:26 -0700870 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300871 [IORING_OP_FILES_UPDATE] = {
Jens Axboe0f203762020-10-14 09:23:55 -0600872 .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_MM,
Jens Axboed3656342019-12-18 09:50:26 -0700873 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300874 [IORING_OP_STATX] = {
Jens Axboe0f203762020-10-14 09:23:55 -0600875 .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_MM |
876 IO_WQ_WORK_FS | IO_WQ_WORK_BLKCG,
Jens Axboed3656342019-12-18 09:50:26 -0700877 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300878 [IORING_OP_READ] = {
Jens Axboe3a6820f2019-12-22 15:19:35 -0700879 .needs_file = 1,
880 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700881 .pollin = 1,
Jens Axboebcda7ba2020-02-23 16:42:51 -0700882 .buffer_select = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700883 .async_size = sizeof(struct io_async_rw),
Jens Axboe0f203762020-10-14 09:23:55 -0600884 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
Jens Axboe3a6820f2019-12-22 15:19:35 -0700885 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300886 [IORING_OP_WRITE] = {
Jens Axboe3a6820f2019-12-22 15:19:35 -0700887 .needs_file = 1,
888 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700889 .pollout = 1,
Jens Axboee8c2bc12020-08-15 18:44:09 -0700890 .async_size = sizeof(struct io_async_rw),
Jens Axboe69228332020-10-20 14:28:41 -0600891 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG |
892 IO_WQ_WORK_FSIZE,
Jens Axboe3a6820f2019-12-22 15:19:35 -0700893 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300894 [IORING_OP_FADVISE] = {
Jens Axboe4840e412019-12-25 22:03:45 -0700895 .needs_file = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600896 .work_flags = IO_WQ_WORK_BLKCG,
Jens Axboe4840e412019-12-25 22:03:45 -0700897 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300898 [IORING_OP_MADVISE] = {
Jens Axboe0f203762020-10-14 09:23:55 -0600899 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
Jens Axboec1ca7572019-12-25 22:18:28 -0700900 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300901 [IORING_OP_SEND] = {
Jens Axboefddafac2020-01-04 20:19:44 -0700902 .needs_file = 1,
903 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700904 .pollout = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600905 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
Jens Axboefddafac2020-01-04 20:19:44 -0700906 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300907 [IORING_OP_RECV] = {
Jens Axboefddafac2020-01-04 20:19:44 -0700908 .needs_file = 1,
909 .unbound_nonreg_file = 1,
Jens Axboe8a727582020-02-20 09:59:44 -0700910 .pollin = 1,
Jens Axboebcda7ba2020-02-23 16:42:51 -0700911 .buffer_select = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600912 .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG,
Jens Axboefddafac2020-01-04 20:19:44 -0700913 },
Pavel Begunkov0463b6c2020-01-18 21:35:38 +0300914 [IORING_OP_OPENAT2] = {
Jens Axboe0f203762020-10-14 09:23:55 -0600915 .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_FS |
916 IO_WQ_WORK_BLKCG,
Jens Axboecebdb982020-01-08 17:59:24 -0700917 },
Jens Axboe3e4827b2020-01-08 15:18:09 -0700918 [IORING_OP_EPOLL_CTL] = {
919 .unbound_nonreg_file = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600920 .work_flags = IO_WQ_WORK_FILES,
Jens Axboe3e4827b2020-01-08 15:18:09 -0700921 },
Pavel Begunkov7d67af22020-02-24 11:32:45 +0300922 [IORING_OP_SPLICE] = {
923 .needs_file = 1,
924 .hash_reg_file = 1,
925 .unbound_nonreg_file = 1,
Jens Axboe0f203762020-10-14 09:23:55 -0600926 .work_flags = IO_WQ_WORK_BLKCG,
Jens Axboeddf0322d2020-02-23 16:41:33 -0700927 },
928 [IORING_OP_PROVIDE_BUFFERS] = {},
Jens Axboe067524e2020-03-02 16:32:28 -0700929 [IORING_OP_REMOVE_BUFFERS] = {},
Pavel Begunkovf2a8d5c2020-05-17 14:18:06 +0300930 [IORING_OP_TEE] = {
931 .needs_file = 1,
932 .hash_reg_file = 1,
933 .unbound_nonreg_file = 1,
934 },
Jens Axboed3656342019-12-18 09:50:26 -0700935};
936
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -0700937enum io_mem_account {
938 ACCT_LOCKED,
939 ACCT_PINNED,
940};
941
Pavel Begunkov81b68a52020-07-30 18:43:46 +0300942static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
943 struct io_comp_state *cs);
Jens Axboe78e19bb2019-11-06 15:21:34 -0700944static void io_cqring_fill_event(struct io_kiocb *req, long res);
Jackie Liuec9c02a2019-11-08 23:50:36 +0800945static void io_put_req(struct io_kiocb *req);
Pavel Begunkov216578e2020-10-13 09:44:00 +0100946static void io_put_req_deferred(struct io_kiocb *req, int nr);
Jens Axboec40f6372020-06-25 15:39:59 -0600947static void io_double_put_req(struct io_kiocb *req);
Jens Axboe94ae5e72019-11-14 19:39:52 -0700948static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req);
Jens Axboe7271ef32020-08-10 09:55:22 -0600949static void __io_queue_linked_timeout(struct io_kiocb *req);
Jens Axboe94ae5e72019-11-14 19:39:52 -0700950static void io_queue_linked_timeout(struct io_kiocb *req);
Jens Axboe05f3fb32019-12-09 11:22:50 -0700951static int __io_sqe_files_update(struct io_ring_ctx *ctx,
952 struct io_uring_files_update *ip,
953 unsigned nr_args);
Pavel Begunkov3ca405e2020-07-13 23:37:08 +0300954static void __io_clean_op(struct io_kiocb *req);
Pavel Begunkov8371adf2020-10-10 18:34:08 +0100955static struct file *io_file_get(struct io_submit_state *state,
956 struct io_kiocb *req, int fd, bool fixed);
Pavel Begunkovc1379e22020-09-30 22:57:56 +0300957static void __io_queue_sqe(struct io_kiocb *req, struct io_comp_state *cs);
Jens Axboe4349f302020-07-09 15:07:01 -0600958static void io_file_put_work(struct work_struct *work);
Jens Axboede0617e2019-04-06 21:51:27 -0600959
Jens Axboeb63534c2020-06-04 11:28:00 -0600960static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
961 struct iovec **iovec, struct iov_iter *iter,
962 bool needs_lock);
Jens Axboeff6165b2020-08-13 09:47:43 -0600963static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
964 const struct iovec *fast_iov,
Jens Axboe227c0c92020-08-13 11:51:40 -0600965 struct iov_iter *iter, bool force);
Jens Axboe2b188cc2019-01-07 10:46:33 -0700966
967static struct kmem_cache *req_cachep;
968
Jens Axboe09186822020-10-13 15:01:40 -0600969static const struct file_operations io_uring_fops;
Jens Axboe2b188cc2019-01-07 10:46:33 -0700970
971struct sock *io_uring_get_socket(struct file *file)
972{
973#if defined(CONFIG_UNIX)
974 if (file->f_op == &io_uring_fops) {
975 struct io_ring_ctx *ctx = file->private_data;
976
977 return ctx->ring_sock->sk;
978 }
979#endif
980 return NULL;
981}
982EXPORT_SYMBOL(io_uring_get_socket);
983
Pavel Begunkov3ca405e2020-07-13 23:37:08 +0300984static inline void io_clean_op(struct io_kiocb *req)
985{
Pavel Begunkovbb175342020-08-20 11:33:35 +0300986 if (req->flags & (REQ_F_NEED_CLEANUP | REQ_F_BUFFER_SELECTED |
987 REQ_F_INFLIGHT))
Pavel Begunkov3ca405e2020-07-13 23:37:08 +0300988 __io_clean_op(req);
989}
990
Jens Axboe4349f302020-07-09 15:07:01 -0600991static void io_sq_thread_drop_mm(void)
Jens Axboec40f6372020-06-25 15:39:59 -0600992{
993 struct mm_struct *mm = current->mm;
994
995 if (mm) {
996 kthread_unuse_mm(mm);
997 mmput(mm);
Jens Axboe4b70cf92020-11-02 10:39:05 -0700998 current->mm = NULL;
Jens Axboec40f6372020-06-25 15:39:59 -0600999 }
1000}
1001
1002static int __io_sq_thread_acquire_mm(struct io_ring_ctx *ctx)
1003{
Jens Axboe4b70cf92020-11-02 10:39:05 -07001004 struct mm_struct *mm;
1005
1006 if (current->mm)
1007 return 0;
1008
1009 /* Should never happen */
1010 if (unlikely(!(ctx->flags & IORING_SETUP_SQPOLL)))
1011 return -EFAULT;
1012
1013 task_lock(ctx->sqo_task);
1014 mm = ctx->sqo_task->mm;
1015 if (unlikely(!mm || !mmget_not_zero(mm)))
1016 mm = NULL;
1017 task_unlock(ctx->sqo_task);
1018
1019 if (mm) {
1020 kthread_use_mm(mm);
1021 return 0;
Jens Axboec40f6372020-06-25 15:39:59 -06001022 }
1023
Jens Axboe4b70cf92020-11-02 10:39:05 -07001024 return -EFAULT;
Jens Axboec40f6372020-06-25 15:39:59 -06001025}
1026
1027static int io_sq_thread_acquire_mm(struct io_ring_ctx *ctx,
1028 struct io_kiocb *req)
1029{
Jens Axboe0f203762020-10-14 09:23:55 -06001030 if (!(io_op_defs[req->opcode].work_flags & IO_WQ_WORK_MM))
Jens Axboec40f6372020-06-25 15:39:59 -06001031 return 0;
1032 return __io_sq_thread_acquire_mm(ctx);
1033}
1034
Dennis Zhou91d8f512020-09-16 13:41:05 -07001035static void io_sq_thread_associate_blkcg(struct io_ring_ctx *ctx,
1036 struct cgroup_subsys_state **cur_css)
1037
1038{
1039#ifdef CONFIG_BLK_CGROUP
1040 /* puts the old one when swapping */
1041 if (*cur_css != ctx->sqo_blkcg_css) {
1042 kthread_associate_blkcg(ctx->sqo_blkcg_css);
1043 *cur_css = ctx->sqo_blkcg_css;
1044 }
1045#endif
1046}
1047
1048static void io_sq_thread_unassociate_blkcg(void)
1049{
1050#ifdef CONFIG_BLK_CGROUP
1051 kthread_associate_blkcg(NULL);
1052#endif
1053}
1054
Jens Axboec40f6372020-06-25 15:39:59 -06001055static inline void req_set_fail_links(struct io_kiocb *req)
1056{
1057 if ((req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) == REQ_F_LINK)
1058 req->flags |= REQ_F_FAIL_LINK;
1059}
Jens Axboe4a38aed22020-05-14 17:21:15 -06001060
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08001061/*
Jens Axboe1e6fa522020-10-15 08:46:24 -06001062 * None of these are dereferenced, they are simply used to check if any of
1063 * them have changed. If we're under current and check they are still the
1064 * same, we're fine to grab references to them for actual out-of-line use.
1065 */
1066static void io_init_identity(struct io_identity *id)
1067{
1068 id->files = current->files;
1069 id->mm = current->mm;
1070#ifdef CONFIG_BLK_CGROUP
1071 rcu_read_lock();
1072 id->blkcg_css = blkcg_css();
1073 rcu_read_unlock();
1074#endif
1075 id->creds = current_cred();
1076 id->nsproxy = current->nsproxy;
1077 id->fs = current->fs;
1078 id->fsize = rlimit(RLIMIT_FSIZE);
Jens Axboe4ea33a92020-10-15 13:46:44 -06001079#ifdef CONFIG_AUDIT
1080 id->loginuid = current->loginuid;
1081 id->sessionid = current->sessionid;
1082#endif
Jens Axboe1e6fa522020-10-15 08:46:24 -06001083 refcount_set(&id->count, 1);
1084}
1085
Pavel Begunkovec99ca62020-10-18 10:17:38 +01001086static inline void __io_req_init_async(struct io_kiocb *req)
1087{
1088 memset(&req->work, 0, sizeof(req->work));
1089 req->flags |= REQ_F_WORK_INITIALIZED;
1090}
1091
Jens Axboe1e6fa522020-10-15 08:46:24 -06001092/*
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08001093 * Note: must call io_req_init_async() for the first time you
1094 * touch any members of io_wq_work.
1095 */
1096static inline void io_req_init_async(struct io_kiocb *req)
1097{
Jens Axboe500a3732020-10-15 17:38:03 -06001098 struct io_uring_task *tctx = current->io_uring;
1099
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08001100 if (req->flags & REQ_F_WORK_INITIALIZED)
1101 return;
1102
Pavel Begunkovec99ca62020-10-18 10:17:38 +01001103 __io_req_init_async(req);
Jens Axboe500a3732020-10-15 17:38:03 -06001104
1105 /* Grab a ref if this isn't our static identity */
1106 req->work.identity = tctx->identity;
1107 if (tctx->identity != &tctx->__identity)
1108 refcount_inc(&req->work.identity->count);
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08001109}
1110
Pavel Begunkov0cdaf762020-05-17 14:13:40 +03001111static inline bool io_async_submit(struct io_ring_ctx *ctx)
1112{
1113 return ctx->flags & IORING_SETUP_SQPOLL;
1114}
1115
Jens Axboe2b188cc2019-01-07 10:46:33 -07001116static void io_ring_ctx_ref_free(struct percpu_ref *ref)
1117{
1118 struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
1119
Jens Axboe0f158b42020-05-14 17:18:39 -06001120 complete(&ctx->ref_comp);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001121}
1122
Pavel Begunkov8eb7e2d2020-06-29 13:13:02 +03001123static inline bool io_is_timeout_noseq(struct io_kiocb *req)
1124{
1125 return !req->timeout.off;
1126}
1127
Jens Axboe2b188cc2019-01-07 10:46:33 -07001128static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
1129{
1130 struct io_ring_ctx *ctx;
Jens Axboe78076bb2019-12-04 19:56:40 -07001131 int hash_bits;
Jens Axboe2b188cc2019-01-07 10:46:33 -07001132
1133 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1134 if (!ctx)
1135 return NULL;
1136
Jens Axboe0ddf92e2019-11-08 08:52:53 -07001137 ctx->fallback_req = kmem_cache_alloc(req_cachep, GFP_KERNEL);
1138 if (!ctx->fallback_req)
1139 goto err;
1140
Jens Axboe78076bb2019-12-04 19:56:40 -07001141 /*
1142 * Use 5 bits less than the max cq entries, that should give us around
1143 * 32 entries per hash list if totally full and uniformly spread.
1144 */
1145 hash_bits = ilog2(p->cq_entries);
1146 hash_bits -= 5;
1147 if (hash_bits <= 0)
1148 hash_bits = 1;
1149 ctx->cancel_hash_bits = hash_bits;
1150 ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
1151 GFP_KERNEL);
1152 if (!ctx->cancel_hash)
1153 goto err;
1154 __hash_init(ctx->cancel_hash, 1U << hash_bits);
1155
Roman Gushchin21482892019-05-07 10:01:48 -07001156 if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
Jens Axboe206aefd2019-11-07 18:27:42 -07001157 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
1158 goto err;
Jens Axboe2b188cc2019-01-07 10:46:33 -07001159
1160 ctx->flags = p->flags;
Jens Axboe90554202020-09-03 12:12:41 -06001161 init_waitqueue_head(&ctx->sqo_sq_wait);
Jens Axboe69fb2132020-09-14 11:16:23 -06001162 INIT_LIST_HEAD(&ctx->sqd_list);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001163 init_waitqueue_head(&ctx->cq_wait);
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001164 INIT_LIST_HEAD(&ctx->cq_overflow_list);
Jens Axboe0f158b42020-05-14 17:18:39 -06001165 init_completion(&ctx->ref_comp);
1166 init_completion(&ctx->sq_thread_comp);
Jens Axboe5a2e7452020-02-23 16:23:11 -07001167 idr_init(&ctx->io_buffer_idr);
Jens Axboe071698e2020-01-28 10:04:42 -07001168 idr_init(&ctx->personality_idr);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001169 mutex_init(&ctx->uring_lock);
1170 init_waitqueue_head(&ctx->wait);
1171 spin_lock_init(&ctx->completion_lock);
Pavel Begunkov540e32a2020-07-13 23:37:09 +03001172 INIT_LIST_HEAD(&ctx->iopoll_list);
Jens Axboede0617e2019-04-06 21:51:27 -06001173 INIT_LIST_HEAD(&ctx->defer_list);
Jens Axboe5262f562019-09-17 12:26:57 -06001174 INIT_LIST_HEAD(&ctx->timeout_list);
Jens Axboefcb323c2019-10-24 12:39:47 -06001175 init_waitqueue_head(&ctx->inflight_wait);
1176 spin_lock_init(&ctx->inflight_lock);
1177 INIT_LIST_HEAD(&ctx->inflight_list);
Jens Axboe4a38aed22020-05-14 17:21:15 -06001178 INIT_DELAYED_WORK(&ctx->file_put_work, io_file_put_work);
1179 init_llist_head(&ctx->file_put_llist);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001180 return ctx;
Jens Axboe206aefd2019-11-07 18:27:42 -07001181err:
Jens Axboe0ddf92e2019-11-08 08:52:53 -07001182 if (ctx->fallback_req)
1183 kmem_cache_free(req_cachep, ctx->fallback_req);
Jens Axboe78076bb2019-12-04 19:56:40 -07001184 kfree(ctx->cancel_hash);
Jens Axboe206aefd2019-11-07 18:27:42 -07001185 kfree(ctx);
1186 return NULL;
Jens Axboe2b188cc2019-01-07 10:46:33 -07001187}
1188
Pavel Begunkov9cf7c102020-07-13 23:37:15 +03001189static bool req_need_defer(struct io_kiocb *req, u32 seq)
Jens Axboede0617e2019-04-06 21:51:27 -06001190{
Jens Axboe2bc99302020-07-09 09:43:27 -06001191 if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
1192 struct io_ring_ctx *ctx = req->ctx;
Jackie Liua197f662019-11-08 08:09:12 -07001193
Pavel Begunkov9cf7c102020-07-13 23:37:15 +03001194 return seq != ctx->cached_cq_tail
Pavel Begunkov2c3bac6d2020-10-18 10:17:40 +01001195 + READ_ONCE(ctx->cached_cq_overflow);
Jens Axboe2bc99302020-07-09 09:43:27 -06001196 }
Jens Axboe7adf4ea2019-10-10 21:42:58 -06001197
Bob Liu9d858b22019-11-13 18:06:25 +08001198 return false;
Jens Axboe7adf4ea2019-10-10 21:42:58 -06001199}
1200
Jens Axboede0617e2019-04-06 21:51:27 -06001201static void __io_commit_cqring(struct io_ring_ctx *ctx)
Jens Axboe2b188cc2019-01-07 10:46:33 -07001202{
Hristo Venev75b28af2019-08-26 17:23:46 +00001203 struct io_rings *rings = ctx->rings;
Jens Axboe2b188cc2019-01-07 10:46:33 -07001204
Pavel Begunkov07910152020-01-17 03:52:46 +03001205 /* order cqe stores with ring update */
1206 smp_store_release(&rings->cq.tail, ctx->cached_cq_tail);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001207
Pavel Begunkov07910152020-01-17 03:52:46 +03001208 if (wq_has_sleeper(&ctx->cq_wait)) {
1209 wake_up_interruptible(&ctx->cq_wait);
1210 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001211 }
1212}
1213
Jens Axboe5c3462c2020-10-15 09:02:33 -06001214static void io_put_identity(struct io_uring_task *tctx, struct io_kiocb *req)
Jens Axboe1e6fa522020-10-15 08:46:24 -06001215{
Jens Axboe500a3732020-10-15 17:38:03 -06001216 if (req->work.identity == &tctx->__identity)
Jens Axboe1e6fa522020-10-15 08:46:24 -06001217 return;
1218 if (refcount_dec_and_test(&req->work.identity->count))
1219 kfree(req->work.identity);
1220}
1221
Pavel Begunkov4edf20f2020-10-13 09:43:59 +01001222static void io_req_clean_work(struct io_kiocb *req)
Jens Axboecccf0ee2020-01-27 16:34:48 -07001223{
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08001224 if (!(req->flags & REQ_F_WORK_INITIALIZED))
Pavel Begunkov4edf20f2020-10-13 09:43:59 +01001225 return;
Jens Axboe51a4cc12020-08-10 10:55:56 -06001226
1227 req->flags &= ~REQ_F_WORK_INITIALIZED;
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08001228
Jens Axboedfead8a2020-10-14 10:12:37 -06001229 if (req->work.flags & IO_WQ_WORK_MM) {
Jens Axboe98447d62020-10-14 10:48:51 -06001230 mmdrop(req->work.identity->mm);
Jens Axboedfead8a2020-10-14 10:12:37 -06001231 req->work.flags &= ~IO_WQ_WORK_MM;
Jens Axboecccf0ee2020-01-27 16:34:48 -07001232 }
Dennis Zhou91d8f512020-09-16 13:41:05 -07001233#ifdef CONFIG_BLK_CGROUP
Jens Axboedfead8a2020-10-14 10:12:37 -06001234 if (req->work.flags & IO_WQ_WORK_BLKCG) {
Jens Axboe98447d62020-10-14 10:48:51 -06001235 css_put(req->work.identity->blkcg_css);
Jens Axboedfead8a2020-10-14 10:12:37 -06001236 req->work.flags &= ~IO_WQ_WORK_BLKCG;
Jens Axboecccf0ee2020-01-27 16:34:48 -07001237 }
Jens Axboedfead8a2020-10-14 10:12:37 -06001238#endif
1239 if (req->work.flags & IO_WQ_WORK_CREDS) {
Jens Axboe98447d62020-10-14 10:48:51 -06001240 put_cred(req->work.identity->creds);
Jens Axboedfead8a2020-10-14 10:12:37 -06001241 req->work.flags &= ~IO_WQ_WORK_CREDS;
1242 }
1243 if (req->work.flags & IO_WQ_WORK_FS) {
Jens Axboe98447d62020-10-14 10:48:51 -06001244 struct fs_struct *fs = req->work.identity->fs;
Jens Axboeff002b32020-02-07 16:05:21 -07001245
Jens Axboe98447d62020-10-14 10:48:51 -06001246 spin_lock(&req->work.identity->fs->lock);
Jens Axboeff002b32020-02-07 16:05:21 -07001247 if (--fs->users)
1248 fs = NULL;
Jens Axboe98447d62020-10-14 10:48:51 -06001249 spin_unlock(&req->work.identity->fs->lock);
Jens Axboeff002b32020-02-07 16:05:21 -07001250 if (fs)
1251 free_fs_struct(fs);
Jens Axboedfead8a2020-10-14 10:12:37 -06001252 req->work.flags &= ~IO_WQ_WORK_FS;
Jens Axboeff002b32020-02-07 16:05:21 -07001253 }
Jens Axboe51a4cc12020-08-10 10:55:56 -06001254
Jens Axboe5c3462c2020-10-15 09:02:33 -06001255 io_put_identity(req->task->io_uring, req);
Jens Axboe1e6fa522020-10-15 08:46:24 -06001256}
1257
1258/*
1259 * Create a private copy of io_identity, since some fields don't match
1260 * the current context.
1261 */
1262static bool io_identity_cow(struct io_kiocb *req)
1263{
Jens Axboe5c3462c2020-10-15 09:02:33 -06001264 struct io_uring_task *tctx = current->io_uring;
Jens Axboe1e6fa522020-10-15 08:46:24 -06001265 const struct cred *creds = NULL;
1266 struct io_identity *id;
1267
1268 if (req->work.flags & IO_WQ_WORK_CREDS)
1269 creds = req->work.identity->creds;
1270
1271 id = kmemdup(req->work.identity, sizeof(*id), GFP_KERNEL);
1272 if (unlikely(!id)) {
1273 req->work.flags |= IO_WQ_WORK_CANCEL;
1274 return false;
1275 }
1276
1277 /*
1278 * We can safely just re-init the creds we copied Either the field
1279 * matches the current one, or we haven't grabbed it yet. The only
1280 * exception is ->creds, through registered personalities, so handle
1281 * that one separately.
1282 */
1283 io_init_identity(id);
1284 if (creds)
1285 req->work.identity->creds = creds;
1286
1287 /* add one for this request */
1288 refcount_inc(&id->count);
1289
Jens Axboecb8a8ae2020-11-03 12:19:07 -07001290 /* drop tctx and req identity references, if needed */
1291 if (tctx->identity != &tctx->__identity &&
1292 refcount_dec_and_test(&tctx->identity->count))
1293 kfree(tctx->identity);
1294 if (req->work.identity != &tctx->__identity &&
1295 refcount_dec_and_test(&req->work.identity->count))
Jens Axboe1e6fa522020-10-15 08:46:24 -06001296 kfree(req->work.identity);
1297
1298 req->work.identity = id;
Jens Axboe500a3732020-10-15 17:38:03 -06001299 tctx->identity = id;
Jens Axboe1e6fa522020-10-15 08:46:24 -06001300 return true;
1301}
1302
1303static bool io_grab_identity(struct io_kiocb *req)
1304{
1305 const struct io_op_def *def = &io_op_defs[req->opcode];
Jens Axboe5c3462c2020-10-15 09:02:33 -06001306 struct io_identity *id = req->work.identity;
Jens Axboe1e6fa522020-10-15 08:46:24 -06001307 struct io_ring_ctx *ctx = req->ctx;
1308
Jens Axboe69228332020-10-20 14:28:41 -06001309 if (def->work_flags & IO_WQ_WORK_FSIZE) {
1310 if (id->fsize != rlimit(RLIMIT_FSIZE))
1311 return false;
1312 req->work.flags |= IO_WQ_WORK_FSIZE;
1313 }
Jens Axboe1e6fa522020-10-15 08:46:24 -06001314
1315 if (!(req->work.flags & IO_WQ_WORK_FILES) &&
1316 (def->work_flags & IO_WQ_WORK_FILES) &&
1317 !(req->flags & REQ_F_NO_FILE_TABLE)) {
1318 if (id->files != current->files ||
1319 id->nsproxy != current->nsproxy)
1320 return false;
1321 atomic_inc(&id->files->count);
1322 get_nsproxy(id->nsproxy);
1323 req->flags |= REQ_F_INFLIGHT;
1324
1325 spin_lock_irq(&ctx->inflight_lock);
1326 list_add(&req->inflight_entry, &ctx->inflight_list);
1327 spin_unlock_irq(&ctx->inflight_lock);
1328 req->work.flags |= IO_WQ_WORK_FILES;
1329 }
1330#ifdef CONFIG_BLK_CGROUP
1331 if (!(req->work.flags & IO_WQ_WORK_BLKCG) &&
1332 (def->work_flags & IO_WQ_WORK_BLKCG)) {
1333 rcu_read_lock();
1334 if (id->blkcg_css != blkcg_css()) {
1335 rcu_read_unlock();
1336 return false;
1337 }
1338 /*
1339 * This should be rare, either the cgroup is dying or the task
1340 * is moving cgroups. Just punt to root for the handful of ios.
1341 */
1342 if (css_tryget_online(id->blkcg_css))
1343 req->work.flags |= IO_WQ_WORK_BLKCG;
1344 rcu_read_unlock();
1345 }
1346#endif
1347 if (!(req->work.flags & IO_WQ_WORK_CREDS)) {
1348 if (id->creds != current_cred())
1349 return false;
1350 get_cred(id->creds);
1351 req->work.flags |= IO_WQ_WORK_CREDS;
1352 }
Jens Axboe4ea33a92020-10-15 13:46:44 -06001353#ifdef CONFIG_AUDIT
1354 if (!uid_eq(current->loginuid, id->loginuid) ||
1355 current->sessionid != id->sessionid)
1356 return false;
1357#endif
Jens Axboe1e6fa522020-10-15 08:46:24 -06001358 if (!(req->work.flags & IO_WQ_WORK_FS) &&
1359 (def->work_flags & IO_WQ_WORK_FS)) {
1360 if (current->fs != id->fs)
1361 return false;
1362 spin_lock(&id->fs->lock);
1363 if (!id->fs->in_exec) {
1364 id->fs->users++;
1365 req->work.flags |= IO_WQ_WORK_FS;
1366 } else {
1367 req->work.flags |= IO_WQ_WORK_CANCEL;
1368 }
1369 spin_unlock(&current->fs->lock);
1370 }
1371
1372 return true;
Jens Axboe561fb042019-10-24 07:25:42 -06001373}
1374
Pavel Begunkovcbdcb432020-06-29 19:18:43 +03001375static void io_prep_async_work(struct io_kiocb *req)
Jens Axboe561fb042019-10-24 07:25:42 -06001376{
Jens Axboed3656342019-12-18 09:50:26 -07001377 const struct io_op_def *def = &io_op_defs[req->opcode];
Pavel Begunkov23329512020-10-10 18:34:06 +01001378 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe5c3462c2020-10-15 09:02:33 -06001379 struct io_identity *id;
Jens Axboe54a91f32019-09-10 09:15:04 -06001380
Pavel Begunkov16d59802020-07-12 16:16:47 +03001381 io_req_init_async(req);
Jens Axboe5c3462c2020-10-15 09:02:33 -06001382 id = req->work.identity;
Pavel Begunkov16d59802020-07-12 16:16:47 +03001383
Pavel Begunkovfeaadc42020-10-22 16:47:16 +01001384 if (req->flags & REQ_F_FORCE_ASYNC)
1385 req->work.flags |= IO_WQ_WORK_CONCURRENT;
1386
Jens Axboed3656342019-12-18 09:50:26 -07001387 if (req->flags & REQ_F_ISREG) {
Pavel Begunkov23329512020-10-10 18:34:06 +01001388 if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
Pavel Begunkov8766dd52020-03-14 00:31:04 +03001389 io_wq_hash_work(&req->work, file_inode(req->file));
Jens Axboed3656342019-12-18 09:50:26 -07001390 } else {
1391 if (def->unbound_nonreg_file)
Jens Axboe3529d8c2019-12-19 18:24:38 -07001392 req->work.flags |= IO_WQ_WORK_UNBOUND;
Jens Axboe54a91f32019-09-10 09:15:04 -06001393 }
Pavel Begunkov23329512020-10-10 18:34:06 +01001394
Jens Axboe1e6fa522020-10-15 08:46:24 -06001395 /* ->mm can never change on us */
Jens Axboedfead8a2020-10-14 10:12:37 -06001396 if (!(req->work.flags & IO_WQ_WORK_MM) &&
1397 (def->work_flags & IO_WQ_WORK_MM)) {
Jens Axboe1e6fa522020-10-15 08:46:24 -06001398 mmgrab(id->mm);
Jens Axboedfead8a2020-10-14 10:12:37 -06001399 req->work.flags |= IO_WQ_WORK_MM;
Pavel Begunkov23329512020-10-10 18:34:06 +01001400 }
Jens Axboe1e6fa522020-10-15 08:46:24 -06001401
1402 /* if we fail grabbing identity, we must COW, regrab, and retry */
1403 if (io_grab_identity(req))
1404 return;
1405
1406 if (!io_identity_cow(req))
1407 return;
1408
1409 /* can't fail at this point */
1410 if (!io_grab_identity(req))
1411 WARN_ON(1);
Jens Axboe561fb042019-10-24 07:25:42 -06001412}
1413
Pavel Begunkovcbdcb432020-06-29 19:18:43 +03001414static void io_prep_async_link(struct io_kiocb *req)
1415{
1416 struct io_kiocb *cur;
1417
1418 io_prep_async_work(req);
1419 if (req->flags & REQ_F_LINK_HEAD)
1420 list_for_each_entry(cur, &req->link_list, link_list)
1421 io_prep_async_work(cur);
1422}
1423
Jens Axboe7271ef32020-08-10 09:55:22 -06001424static struct io_kiocb *__io_queue_async_work(struct io_kiocb *req)
Jens Axboe561fb042019-10-24 07:25:42 -06001425{
Jackie Liua197f662019-11-08 08:09:12 -07001426 struct io_ring_ctx *ctx = req->ctx;
Pavel Begunkovcbdcb432020-06-29 19:18:43 +03001427 struct io_kiocb *link = io_prep_linked_timeout(req);
Jens Axboe561fb042019-10-24 07:25:42 -06001428
Pavel Begunkov8766dd52020-03-14 00:31:04 +03001429 trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
1430 &req->work, req->flags);
1431 io_wq_enqueue(ctx->io_wq, &req->work);
Jens Axboe7271ef32020-08-10 09:55:22 -06001432 return link;
Jens Axboe18d9be12019-09-10 09:13:05 -06001433}
1434
Pavel Begunkovcbdcb432020-06-29 19:18:43 +03001435static void io_queue_async_work(struct io_kiocb *req)
1436{
Jens Axboe7271ef32020-08-10 09:55:22 -06001437 struct io_kiocb *link;
1438
Pavel Begunkovcbdcb432020-06-29 19:18:43 +03001439 /* init ->work of the whole link before punting */
1440 io_prep_async_link(req);
Jens Axboe7271ef32020-08-10 09:55:22 -06001441 link = __io_queue_async_work(req);
1442
1443 if (link)
1444 io_queue_linked_timeout(link);
Pavel Begunkovcbdcb432020-06-29 19:18:43 +03001445}
1446
Jens Axboe5262f562019-09-17 12:26:57 -06001447static void io_kill_timeout(struct io_kiocb *req)
1448{
Jens Axboee8c2bc12020-08-15 18:44:09 -07001449 struct io_timeout_data *io = req->async_data;
Jens Axboe5262f562019-09-17 12:26:57 -06001450 int ret;
1451
Jens Axboee8c2bc12020-08-15 18:44:09 -07001452 ret = hrtimer_try_to_cancel(&io->timer);
Jens Axboe5262f562019-09-17 12:26:57 -06001453 if (ret != -1) {
Pavel Begunkov01cec8c2020-07-30 18:43:50 +03001454 atomic_set(&req->ctx->cq_timeouts,
1455 atomic_read(&req->ctx->cq_timeouts) + 1);
Pavel Begunkov135fcde2020-07-13 23:37:12 +03001456 list_del_init(&req->timeout.list);
Jens Axboe78e19bb2019-11-06 15:21:34 -07001457 io_cqring_fill_event(req, 0);
Pavel Begunkov216578e2020-10-13 09:44:00 +01001458 io_put_req_deferred(req, 1);
Jens Axboe5262f562019-09-17 12:26:57 -06001459 }
1460}
1461
Jens Axboef3606e32020-09-22 08:18:24 -06001462static bool io_task_match(struct io_kiocb *req, struct task_struct *tsk)
1463{
1464 struct io_ring_ctx *ctx = req->ctx;
1465
1466 if (!tsk || req->task == tsk)
1467 return true;
Jens Axboe534ca6d2020-09-02 13:52:19 -06001468 if (ctx->flags & IORING_SETUP_SQPOLL) {
1469 if (ctx->sq_data && req->task == ctx->sq_data->thread)
1470 return true;
1471 }
Jens Axboef3606e32020-09-22 08:18:24 -06001472 return false;
1473}
1474
Jens Axboe76e1b642020-09-26 15:05:03 -06001475/*
1476 * Returns true if we found and killed one or more timeouts
1477 */
1478static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk)
Jens Axboe5262f562019-09-17 12:26:57 -06001479{
1480 struct io_kiocb *req, *tmp;
Jens Axboe76e1b642020-09-26 15:05:03 -06001481 int canceled = 0;
Jens Axboe5262f562019-09-17 12:26:57 -06001482
1483 spin_lock_irq(&ctx->completion_lock);
Jens Axboef3606e32020-09-22 08:18:24 -06001484 list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
Jens Axboe76e1b642020-09-26 15:05:03 -06001485 if (io_task_match(req, tsk)) {
Jens Axboef3606e32020-09-22 08:18:24 -06001486 io_kill_timeout(req);
Jens Axboe76e1b642020-09-26 15:05:03 -06001487 canceled++;
1488 }
Jens Axboef3606e32020-09-22 08:18:24 -06001489 }
Jens Axboe5262f562019-09-17 12:26:57 -06001490 spin_unlock_irq(&ctx->completion_lock);
Jens Axboe76e1b642020-09-26 15:05:03 -06001491 return canceled != 0;
Jens Axboe5262f562019-09-17 12:26:57 -06001492}
1493
Pavel Begunkov04518942020-05-26 20:34:05 +03001494static void __io_queue_deferred(struct io_ring_ctx *ctx)
1495{
1496 do {
Pavel Begunkov27dc8332020-07-13 23:37:14 +03001497 struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
1498 struct io_defer_entry, list);
Jens Axboe7271ef32020-08-10 09:55:22 -06001499 struct io_kiocb *link;
Pavel Begunkov04518942020-05-26 20:34:05 +03001500
Pavel Begunkov9cf7c102020-07-13 23:37:15 +03001501 if (req_need_defer(de->req, de->seq))
Pavel Begunkov04518942020-05-26 20:34:05 +03001502 break;
Pavel Begunkov27dc8332020-07-13 23:37:14 +03001503 list_del_init(&de->list);
Pavel Begunkovcbdcb432020-06-29 19:18:43 +03001504 /* punt-init is done before queueing for defer */
Jens Axboe7271ef32020-08-10 09:55:22 -06001505 link = __io_queue_async_work(de->req);
1506 if (link) {
1507 __io_queue_linked_timeout(link);
1508 /* drop submission reference */
Pavel Begunkov216578e2020-10-13 09:44:00 +01001509 io_put_req_deferred(link, 1);
Jens Axboe7271ef32020-08-10 09:55:22 -06001510 }
Pavel Begunkov27dc8332020-07-13 23:37:14 +03001511 kfree(de);
Pavel Begunkov04518942020-05-26 20:34:05 +03001512 } while (!list_empty(&ctx->defer_list));
1513}
1514
Pavel Begunkov360428f2020-05-30 14:54:17 +03001515static void io_flush_timeouts(struct io_ring_ctx *ctx)
1516{
1517 while (!list_empty(&ctx->timeout_list)) {
1518 struct io_kiocb *req = list_first_entry(&ctx->timeout_list,
Pavel Begunkov135fcde2020-07-13 23:37:12 +03001519 struct io_kiocb, timeout.list);
Pavel Begunkov360428f2020-05-30 14:54:17 +03001520
Pavel Begunkov8eb7e2d2020-06-29 13:13:02 +03001521 if (io_is_timeout_noseq(req))
Pavel Begunkov360428f2020-05-30 14:54:17 +03001522 break;
Pavel Begunkovbfe68a22020-05-30 14:54:18 +03001523 if (req->timeout.target_seq != ctx->cached_cq_tail
1524 - atomic_read(&ctx->cq_timeouts))
Pavel Begunkov360428f2020-05-30 14:54:17 +03001525 break;
Pavel Begunkovbfe68a22020-05-30 14:54:18 +03001526
Pavel Begunkov135fcde2020-07-13 23:37:12 +03001527 list_del_init(&req->timeout.list);
Pavel Begunkov360428f2020-05-30 14:54:17 +03001528 io_kill_timeout(req);
1529 }
1530}
1531
Jens Axboede0617e2019-04-06 21:51:27 -06001532static void io_commit_cqring(struct io_ring_ctx *ctx)
1533{
Pavel Begunkov360428f2020-05-30 14:54:17 +03001534 io_flush_timeouts(ctx);
Jens Axboede0617e2019-04-06 21:51:27 -06001535 __io_commit_cqring(ctx);
1536
Pavel Begunkov04518942020-05-26 20:34:05 +03001537 if (unlikely(!list_empty(&ctx->defer_list)))
1538 __io_queue_deferred(ctx);
Jens Axboede0617e2019-04-06 21:51:27 -06001539}
1540
Jens Axboe90554202020-09-03 12:12:41 -06001541static inline bool io_sqring_full(struct io_ring_ctx *ctx)
1542{
1543 struct io_rings *r = ctx->rings;
1544
1545 return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == r->sq_ring_entries;
1546}
1547
Jens Axboe2b188cc2019-01-07 10:46:33 -07001548static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx)
1549{
Hristo Venev75b28af2019-08-26 17:23:46 +00001550 struct io_rings *rings = ctx->rings;
Jens Axboe2b188cc2019-01-07 10:46:33 -07001551 unsigned tail;
1552
1553 tail = ctx->cached_cq_tail;
Stefan Bühler115e12e2019-04-24 23:54:18 +02001554 /*
1555 * writes to the cq entry need to come after reading head; the
1556 * control dependency is enough as we're using WRITE_ONCE to
1557 * fill the cq entry
1558 */
Hristo Venev75b28af2019-08-26 17:23:46 +00001559 if (tail - READ_ONCE(rings->cq.head) == rings->cq_ring_entries)
Jens Axboe2b188cc2019-01-07 10:46:33 -07001560 return NULL;
1561
1562 ctx->cached_cq_tail++;
Hristo Venev75b28af2019-08-26 17:23:46 +00001563 return &rings->cqes[tail & ctx->cq_mask];
Jens Axboe2b188cc2019-01-07 10:46:33 -07001564}
1565
Jens Axboef2842ab2020-01-08 11:04:00 -07001566static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
1567{
Jens Axboef0b493e2020-02-01 21:30:11 -07001568 if (!ctx->cq_ev_fd)
1569 return false;
Stefano Garzarella7e55a192020-05-15 18:38:05 +02001570 if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
1571 return false;
Jens Axboef2842ab2020-01-08 11:04:00 -07001572 if (!ctx->eventfd_async)
1573 return true;
Jens Axboeb41e9852020-02-17 09:52:41 -07001574 return io_wq_current_is_worker();
Jens Axboef2842ab2020-01-08 11:04:00 -07001575}
1576
Jens Axboeb41e9852020-02-17 09:52:41 -07001577static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
Jens Axboe8c838782019-03-12 15:48:16 -06001578{
1579 if (waitqueue_active(&ctx->wait))
1580 wake_up(&ctx->wait);
Jens Axboe534ca6d2020-09-02 13:52:19 -06001581 if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
1582 wake_up(&ctx->sq_data->wait);
Jens Axboeb41e9852020-02-17 09:52:41 -07001583 if (io_should_trigger_evfd(ctx))
Jens Axboe9b402842019-04-11 11:45:41 -06001584 eventfd_signal(ctx->cq_ev_fd, 1);
Jens Axboe8c838782019-03-12 15:48:16 -06001585}
1586
Pavel Begunkov46930142020-07-30 18:43:49 +03001587static void io_cqring_mark_overflow(struct io_ring_ctx *ctx)
1588{
1589 if (list_empty(&ctx->cq_overflow_list)) {
1590 clear_bit(0, &ctx->sq_check_overflow);
1591 clear_bit(0, &ctx->cq_check_overflow);
1592 ctx->rings->sq_flags &= ~IORING_SQ_CQ_OVERFLOW;
1593 }
1594}
1595
Pavel Begunkov99b32802020-11-04 13:39:31 +00001596static inline bool __io_match_files(struct io_kiocb *req,
1597 struct files_struct *files)
Jens Axboee6c8aa92020-09-28 13:10:13 -06001598{
Pavel Begunkov99b32802020-11-04 13:39:31 +00001599 return ((req->flags & REQ_F_WORK_INITIALIZED) &&
1600 (req->work.flags & IO_WQ_WORK_FILES)) &&
1601 req->work.identity->files == files;
1602}
1603
1604static bool io_match_files(struct io_kiocb *req,
1605 struct files_struct *files)
1606{
1607 struct io_kiocb *link;
1608
Jens Axboee6c8aa92020-09-28 13:10:13 -06001609 if (!files)
1610 return true;
Pavel Begunkov99b32802020-11-04 13:39:31 +00001611 if (__io_match_files(req, files))
1612 return true;
1613 if (req->flags & REQ_F_LINK_HEAD) {
1614 list_for_each_entry(link, &req->link_list, link_list) {
1615 if (__io_match_files(link, files))
1616 return true;
1617 }
1618 }
Jens Axboee6c8aa92020-09-28 13:10:13 -06001619 return false;
1620}
1621
Jens Axboec4a2ed72019-11-21 21:01:26 -07001622/* Returns true if there are no backlogged entries after the flush */
Jens Axboee6c8aa92020-09-28 13:10:13 -06001623static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
1624 struct task_struct *tsk,
1625 struct files_struct *files)
Jens Axboe2b188cc2019-01-07 10:46:33 -07001626{
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001627 struct io_rings *rings = ctx->rings;
Jens Axboee6c8aa92020-09-28 13:10:13 -06001628 struct io_kiocb *req, *tmp;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001629 struct io_uring_cqe *cqe;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001630 unsigned long flags;
1631 LIST_HEAD(list);
1632
1633 if (!force) {
1634 if (list_empty_careful(&ctx->cq_overflow_list))
Jens Axboec4a2ed72019-11-21 21:01:26 -07001635 return true;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001636 if ((ctx->cached_cq_tail - READ_ONCE(rings->cq.head) ==
1637 rings->cq_ring_entries))
Jens Axboec4a2ed72019-11-21 21:01:26 -07001638 return false;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001639 }
1640
1641 spin_lock_irqsave(&ctx->completion_lock, flags);
1642
1643 /* if force is set, the ring is going away. always drop after that */
1644 if (force)
Jens Axboe69b3e542020-01-08 11:01:46 -07001645 ctx->cq_overflow_flushed = 1;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001646
Jens Axboec4a2ed72019-11-21 21:01:26 -07001647 cqe = NULL;
Jens Axboee6c8aa92020-09-28 13:10:13 -06001648 list_for_each_entry_safe(req, tmp, &ctx->cq_overflow_list, compl.list) {
1649 if (tsk && req->task != tsk)
1650 continue;
1651 if (!io_match_files(req, files))
1652 continue;
1653
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001654 cqe = io_get_cqring(ctx);
1655 if (!cqe && !force)
1656 break;
1657
Pavel Begunkov40d8ddd2020-07-13 23:37:11 +03001658 list_move(&req->compl.list, &list);
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001659 if (cqe) {
1660 WRITE_ONCE(cqe->user_data, req->user_data);
1661 WRITE_ONCE(cqe->res, req->result);
Pavel Begunkov0f7e4662020-07-13 23:37:16 +03001662 WRITE_ONCE(cqe->flags, req->compl.cflags);
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001663 } else {
Pavel Begunkov2c3bac6d2020-10-18 10:17:40 +01001664 ctx->cached_cq_overflow++;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001665 WRITE_ONCE(ctx->rings->cq_overflow,
Pavel Begunkov2c3bac6d2020-10-18 10:17:40 +01001666 ctx->cached_cq_overflow);
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001667 }
1668 }
1669
1670 io_commit_cqring(ctx);
Pavel Begunkov46930142020-07-30 18:43:49 +03001671 io_cqring_mark_overflow(ctx);
1672
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001673 spin_unlock_irqrestore(&ctx->completion_lock, flags);
1674 io_cqring_ev_posted(ctx);
1675
1676 while (!list_empty(&list)) {
Pavel Begunkov40d8ddd2020-07-13 23:37:11 +03001677 req = list_first_entry(&list, struct io_kiocb, compl.list);
1678 list_del(&req->compl.list);
Jackie Liuec9c02a2019-11-08 23:50:36 +08001679 io_put_req(req);
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001680 }
Jens Axboec4a2ed72019-11-21 21:01:26 -07001681
1682 return cqe != NULL;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001683}
1684
Jens Axboebcda7ba2020-02-23 16:42:51 -07001685static void __io_cqring_fill_event(struct io_kiocb *req, long res, long cflags)
Jens Axboe2b188cc2019-01-07 10:46:33 -07001686{
Jens Axboe78e19bb2019-11-06 15:21:34 -07001687 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe2b188cc2019-01-07 10:46:33 -07001688 struct io_uring_cqe *cqe;
1689
Jens Axboe78e19bb2019-11-06 15:21:34 -07001690 trace_io_uring_complete(ctx, req->user_data, res);
Jens Axboe51c3ff62019-11-03 06:52:50 -07001691
Jens Axboe2b188cc2019-01-07 10:46:33 -07001692 /*
1693 * If we can't get a cq entry, userspace overflowed the
1694 * submission (by quite a lot). Increment the overflow count in
1695 * the ring.
1696 */
1697 cqe = io_get_cqring(ctx);
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001698 if (likely(cqe)) {
Jens Axboe78e19bb2019-11-06 15:21:34 -07001699 WRITE_ONCE(cqe->user_data, req->user_data);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001700 WRITE_ONCE(cqe->res, res);
Jens Axboebcda7ba2020-02-23 16:42:51 -07001701 WRITE_ONCE(cqe->flags, cflags);
Jens Axboefdaf0832020-10-30 09:37:30 -06001702 } else if (ctx->cq_overflow_flushed ||
1703 atomic_read(&req->task->io_uring->in_idle)) {
Jens Axboe0f212202020-09-13 13:09:39 -06001704 /*
1705 * If we're in ring overflow flush mode, or in task cancel mode,
1706 * then we cannot store the request for later flushing, we need
1707 * to drop it on the floor.
1708 */
Pavel Begunkov2c3bac6d2020-10-18 10:17:40 +01001709 ctx->cached_cq_overflow++;
1710 WRITE_ONCE(ctx->rings->cq_overflow, ctx->cached_cq_overflow);
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001711 } else {
Jens Axboead3eb2c2019-12-18 17:12:20 -07001712 if (list_empty(&ctx->cq_overflow_list)) {
1713 set_bit(0, &ctx->sq_check_overflow);
1714 set_bit(0, &ctx->cq_check_overflow);
Xiaoguang Wang6d5f9042020-07-09 09:15:29 +08001715 ctx->rings->sq_flags |= IORING_SQ_CQ_OVERFLOW;
Jens Axboead3eb2c2019-12-18 17:12:20 -07001716 }
Pavel Begunkov40d8ddd2020-07-13 23:37:11 +03001717 io_clean_op(req);
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07001718 req->result = res;
Pavel Begunkov0f7e4662020-07-13 23:37:16 +03001719 req->compl.cflags = cflags;
Pavel Begunkov40d8ddd2020-07-13 23:37:11 +03001720 refcount_inc(&req->refs);
1721 list_add_tail(&req->compl.list, &ctx->cq_overflow_list);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001722 }
1723}
1724
Jens Axboebcda7ba2020-02-23 16:42:51 -07001725static void io_cqring_fill_event(struct io_kiocb *req, long res)
1726{
1727 __io_cqring_fill_event(req, res, 0);
1728}
1729
Jens Axboee1e16092020-06-22 09:17:17 -06001730static void io_cqring_add_event(struct io_kiocb *req, long res, long cflags)
Jens Axboe2b188cc2019-01-07 10:46:33 -07001731{
Jens Axboe78e19bb2019-11-06 15:21:34 -07001732 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe2b188cc2019-01-07 10:46:33 -07001733 unsigned long flags;
1734
1735 spin_lock_irqsave(&ctx->completion_lock, flags);
Jens Axboebcda7ba2020-02-23 16:42:51 -07001736 __io_cqring_fill_event(req, res, cflags);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001737 io_commit_cqring(ctx);
1738 spin_unlock_irqrestore(&ctx->completion_lock, flags);
1739
Jens Axboe8c838782019-03-12 15:48:16 -06001740 io_cqring_ev_posted(ctx);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001741}
1742
Jens Axboe229a7b62020-06-22 10:13:11 -06001743static void io_submit_flush_completions(struct io_comp_state *cs)
Jens Axboebcda7ba2020-02-23 16:42:51 -07001744{
Jens Axboe229a7b62020-06-22 10:13:11 -06001745 struct io_ring_ctx *ctx = cs->ctx;
1746
1747 spin_lock_irq(&ctx->completion_lock);
1748 while (!list_empty(&cs->list)) {
1749 struct io_kiocb *req;
1750
Pavel Begunkov3ca405e2020-07-13 23:37:08 +03001751 req = list_first_entry(&cs->list, struct io_kiocb, compl.list);
1752 list_del(&req->compl.list);
Pavel Begunkov0f7e4662020-07-13 23:37:16 +03001753 __io_cqring_fill_event(req, req->result, req->compl.cflags);
Pavel Begunkov216578e2020-10-13 09:44:00 +01001754
1755 /*
1756 * io_free_req() doesn't care about completion_lock unless one
1757 * of these flags is set. REQ_F_WORK_INITIALIZED is in the list
1758 * because of a potential deadlock with req->work.fs->lock
1759 */
1760 if (req->flags & (REQ_F_FAIL_LINK|REQ_F_LINK_TIMEOUT
1761 |REQ_F_WORK_INITIALIZED)) {
Jens Axboe229a7b62020-06-22 10:13:11 -06001762 spin_unlock_irq(&ctx->completion_lock);
1763 io_put_req(req);
1764 spin_lock_irq(&ctx->completion_lock);
Pavel Begunkov216578e2020-10-13 09:44:00 +01001765 } else {
1766 io_put_req(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06001767 }
1768 }
1769 io_commit_cqring(ctx);
1770 spin_unlock_irq(&ctx->completion_lock);
1771
1772 io_cqring_ev_posted(ctx);
1773 cs->nr = 0;
1774}
1775
1776static void __io_req_complete(struct io_kiocb *req, long res, unsigned cflags,
1777 struct io_comp_state *cs)
1778{
1779 if (!cs) {
1780 io_cqring_add_event(req, res, cflags);
1781 io_put_req(req);
1782 } else {
Pavel Begunkov3ca405e2020-07-13 23:37:08 +03001783 io_clean_op(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06001784 req->result = res;
Pavel Begunkov0f7e4662020-07-13 23:37:16 +03001785 req->compl.cflags = cflags;
Pavel Begunkov3ca405e2020-07-13 23:37:08 +03001786 list_add_tail(&req->compl.list, &cs->list);
Jens Axboe229a7b62020-06-22 10:13:11 -06001787 if (++cs->nr >= 32)
1788 io_submit_flush_completions(cs);
1789 }
Jens Axboee1e16092020-06-22 09:17:17 -06001790}
1791
1792static void io_req_complete(struct io_kiocb *req, long res)
1793{
Jens Axboe229a7b62020-06-22 10:13:11 -06001794 __io_req_complete(req, res, 0, NULL);
Jens Axboebcda7ba2020-02-23 16:42:51 -07001795}
1796
Jens Axboe0ddf92e2019-11-08 08:52:53 -07001797static inline bool io_is_fallback_req(struct io_kiocb *req)
1798{
1799 return req == (struct io_kiocb *)
1800 ((unsigned long) req->ctx->fallback_req & ~1UL);
1801}
1802
1803static struct io_kiocb *io_get_fallback_req(struct io_ring_ctx *ctx)
1804{
1805 struct io_kiocb *req;
1806
1807 req = ctx->fallback_req;
Bijan Mottahedehdd461af2020-04-29 17:47:50 -07001808 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx->fallback_req))
Jens Axboe0ddf92e2019-11-08 08:52:53 -07001809 return req;
1810
1811 return NULL;
1812}
1813
Pavel Begunkov0553b8b2020-04-08 08:58:45 +03001814static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx,
1815 struct io_submit_state *state)
Jens Axboe2b188cc2019-01-07 10:46:33 -07001816{
Pavel Begunkovf6b6c7d2020-06-21 13:09:53 +03001817 if (!state->free_reqs) {
Pavel Begunkov291b2822020-09-30 22:57:01 +03001818 gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
Jens Axboe2579f912019-01-09 09:10:43 -07001819 size_t sz;
1820 int ret;
1821
1822 sz = min_t(size_t, state->ios_left, ARRAY_SIZE(state->reqs));
Jens Axboefd6fab22019-03-14 16:30:06 -06001823 ret = kmem_cache_alloc_bulk(req_cachep, gfp, sz, state->reqs);
1824
1825 /*
1826 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1827 * retry single alloc to be on the safe side.
1828 */
1829 if (unlikely(ret <= 0)) {
1830 state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
1831 if (!state->reqs[0])
Jens Axboe0ddf92e2019-11-08 08:52:53 -07001832 goto fallback;
Jens Axboefd6fab22019-03-14 16:30:06 -06001833 ret = 1;
1834 }
Pavel Begunkov291b2822020-09-30 22:57:01 +03001835 state->free_reqs = ret;
Jens Axboe2b188cc2019-01-07 10:46:33 -07001836 }
1837
Pavel Begunkov291b2822020-09-30 22:57:01 +03001838 state->free_reqs--;
1839 return state->reqs[state->free_reqs];
Jens Axboe0ddf92e2019-11-08 08:52:53 -07001840fallback:
Pavel Begunkov0553b8b2020-04-08 08:58:45 +03001841 return io_get_fallback_req(ctx);
Jens Axboe2b188cc2019-01-07 10:46:33 -07001842}
1843
Pavel Begunkov8da11c12020-02-24 11:32:44 +03001844static inline void io_put_file(struct io_kiocb *req, struct file *file,
1845 bool fixed)
1846{
1847 if (fixed)
Xiaoguang Wang05589552020-03-31 14:05:18 +08001848 percpu_ref_put(req->fixed_file_refs);
Pavel Begunkov8da11c12020-02-24 11:32:44 +03001849 else
1850 fput(file);
1851}
1852
Pavel Begunkov4edf20f2020-10-13 09:43:59 +01001853static void io_dismantle_req(struct io_kiocb *req)
Jens Axboe2b188cc2019-01-07 10:46:33 -07001854{
Pavel Begunkov3ca405e2020-07-13 23:37:08 +03001855 io_clean_op(req);
Pavel Begunkov929a3af2020-02-19 00:19:09 +03001856
Jens Axboee8c2bc12020-08-15 18:44:09 -07001857 if (req->async_data)
1858 kfree(req->async_data);
Pavel Begunkov8da11c12020-02-24 11:32:44 +03001859 if (req->file)
1860 io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE));
Jens Axboefcb323c2019-10-24 12:39:47 -06001861
Pavel Begunkov4edf20f2020-10-13 09:43:59 +01001862 io_req_clean_work(req);
Pavel Begunkove6543a82020-06-28 12:52:30 +03001863}
Pavel Begunkov2b85edf2019-12-28 14:13:03 +03001864
Pavel Begunkov216578e2020-10-13 09:44:00 +01001865static void __io_free_req(struct io_kiocb *req)
Pavel Begunkove6543a82020-06-28 12:52:30 +03001866{
Jens Axboe0f212202020-09-13 13:09:39 -06001867 struct io_uring_task *tctx = req->task->io_uring;
Jens Axboe51a4cc12020-08-10 10:55:56 -06001868 struct io_ring_ctx *ctx = req->ctx;
Pavel Begunkovecfc5172020-06-29 13:13:03 +03001869
Pavel Begunkov216578e2020-10-13 09:44:00 +01001870 io_dismantle_req(req);
Pavel Begunkove6543a82020-06-28 12:52:30 +03001871
Jens Axboed8a6df12020-10-15 16:24:45 -06001872 percpu_counter_dec(&tctx->inflight);
Jens Axboefdaf0832020-10-30 09:37:30 -06001873 if (atomic_read(&tctx->in_idle))
Jens Axboe0f212202020-09-13 13:09:39 -06001874 wake_up(&tctx->wait);
Jens Axboee3bc8e92020-09-24 08:45:57 -06001875 put_task_struct(req->task);
1876
Pavel Begunkovb1e50e52020-04-08 08:58:44 +03001877 if (likely(!io_is_fallback_req(req)))
1878 kmem_cache_free(req_cachep, req);
1879 else
Pavel Begunkovecfc5172020-06-29 13:13:03 +03001880 clear_bit_unlock(0, (unsigned long *) &ctx->fallback_req);
1881 percpu_ref_put(&ctx->refs);
Jens Axboee65ef562019-03-12 10:16:44 -06001882}
1883
Pavel Begunkovc9abd7a2020-10-22 16:43:11 +01001884static void io_kill_linked_timeout(struct io_kiocb *req)
Jens Axboe9e645e112019-05-10 16:07:28 -06001885{
Jackie Liua197f662019-11-08 08:09:12 -07001886 struct io_ring_ctx *ctx = req->ctx;
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001887 struct io_kiocb *link;
Pavel Begunkovc9abd7a2020-10-22 16:43:11 +01001888 bool cancelled = false;
1889 unsigned long flags;
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001890
Pavel Begunkovc9abd7a2020-10-22 16:43:11 +01001891 spin_lock_irqsave(&ctx->completion_lock, flags);
1892 link = list_first_entry_or_null(&req->link_list, struct io_kiocb,
1893 link_list);
Pavel Begunkov900fad42020-10-19 16:39:16 +01001894 /*
1895 * Can happen if a linked timeout fired and link had been like
1896 * req -> link t-out -> link t-out [-> ...]
1897 */
Pavel Begunkovc9abd7a2020-10-22 16:43:11 +01001898 if (link && (link->flags & REQ_F_LTIMEOUT_ACTIVE)) {
1899 struct io_timeout_data *io = link->async_data;
1900 int ret;
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001901
Pavel Begunkovc9abd7a2020-10-22 16:43:11 +01001902 list_del_init(&link->link_list);
1903 ret = hrtimer_try_to_cancel(&io->timer);
1904 if (ret != -1) {
1905 io_cqring_fill_event(link, -ECANCELED);
1906 io_commit_cqring(ctx);
1907 cancelled = true;
1908 }
1909 }
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001910 req->flags &= ~REQ_F_LINK_TIMEOUT;
Pavel Begunkov216578e2020-10-13 09:44:00 +01001911 spin_unlock_irqrestore(&ctx->completion_lock, flags);
Jens Axboeab0b6452020-06-30 08:43:15 -06001912
Pavel Begunkovc9abd7a2020-10-22 16:43:11 +01001913 if (cancelled) {
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001914 io_cqring_ev_posted(ctx);
Pavel Begunkovc9abd7a2020-10-22 16:43:11 +01001915 io_put_req(link);
1916 }
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001917}
1918
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03001919static struct io_kiocb *io_req_link_next(struct io_kiocb *req)
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001920{
1921 struct io_kiocb *nxt;
Jens Axboe4d7dd462019-11-20 13:03:52 -07001922
Jens Axboe9e645e112019-05-10 16:07:28 -06001923 /*
1924 * The list should never be empty when we are called here. But could
1925 * potentially happen if the chain is messed up, check to be on the
1926 * safe side.
1927 */
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001928 if (unlikely(list_empty(&req->link_list)))
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03001929 return NULL;
Jens Axboe94ae5e72019-11-14 19:39:52 -07001930
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001931 nxt = list_first_entry(&req->link_list, struct io_kiocb, link_list);
1932 list_del_init(&req->link_list);
1933 if (!list_empty(&nxt->link_list))
1934 nxt->flags |= REQ_F_LINK_HEAD;
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03001935 return nxt;
Jens Axboe9e645e112019-05-10 16:07:28 -06001936}
1937
1938/*
Pavel Begunkovdea3b492020-04-12 02:05:04 +03001939 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
Jens Axboe9e645e112019-05-10 16:07:28 -06001940 */
Pavel Begunkovd148ca42020-10-18 10:17:39 +01001941static void io_fail_links(struct io_kiocb *req)
Jens Axboe9e645e112019-05-10 16:07:28 -06001942{
Jens Axboe2665abf2019-11-05 12:40:47 -07001943 struct io_ring_ctx *ctx = req->ctx;
Pavel Begunkovd148ca42020-10-18 10:17:39 +01001944 unsigned long flags;
Jens Axboe9e645e112019-05-10 16:07:28 -06001945
Pavel Begunkovd148ca42020-10-18 10:17:39 +01001946 spin_lock_irqsave(&ctx->completion_lock, flags);
Jens Axboe9e645e112019-05-10 16:07:28 -06001947 while (!list_empty(&req->link_list)) {
Pavel Begunkov44932332019-12-05 16:16:35 +03001948 struct io_kiocb *link = list_first_entry(&req->link_list,
1949 struct io_kiocb, link_list);
Jens Axboe9e645e112019-05-10 16:07:28 -06001950
Pavel Begunkov44932332019-12-05 16:16:35 +03001951 list_del_init(&link->link_list);
Dmitrii Dolgovc826bd72019-10-15 19:02:01 +02001952 trace_io_uring_fail_link(req, link);
Jens Axboe2665abf2019-11-05 12:40:47 -07001953
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001954 io_cqring_fill_event(link, -ECANCELED);
Pavel Begunkov216578e2020-10-13 09:44:00 +01001955
1956 /*
1957 * It's ok to free under spinlock as they're not linked anymore,
1958 * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
1959 * work.fs->lock.
1960 */
1961 if (link->flags & REQ_F_WORK_INITIALIZED)
1962 io_put_req_deferred(link, 2);
1963 else
1964 io_double_put_req(link);
Jens Axboe9e645e112019-05-10 16:07:28 -06001965 }
Jens Axboe2665abf2019-11-05 12:40:47 -07001966
1967 io_commit_cqring(ctx);
Pavel Begunkov216578e2020-10-13 09:44:00 +01001968 spin_unlock_irqrestore(&ctx->completion_lock, flags);
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001969
Jens Axboe2665abf2019-11-05 12:40:47 -07001970 io_cqring_ev_posted(ctx);
Jens Axboe9e645e112019-05-10 16:07:28 -06001971}
1972
Pavel Begunkov3fa5e0f2020-06-30 15:20:43 +03001973static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
Jens Axboe9e645e112019-05-10 16:07:28 -06001974{
Pavel Begunkov9b0d9112020-06-28 12:52:34 +03001975 req->flags &= ~REQ_F_LINK_HEAD;
Pavel Begunkov7c86ffe2020-06-29 13:12:59 +03001976 if (req->flags & REQ_F_LINK_TIMEOUT)
1977 io_kill_linked_timeout(req);
Jens Axboe2665abf2019-11-05 12:40:47 -07001978
Jens Axboe9e645e112019-05-10 16:07:28 -06001979 /*
1980 * If LINK is set, we have dependent requests in this chain. If we
1981 * didn't fail this request, queue the first one up, moving any other
1982 * dependencies to the next request. In case of failure, fail the rest
1983 * of the chain.
1984 */
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03001985 if (likely(!(req->flags & REQ_F_FAIL_LINK)))
1986 return io_req_link_next(req);
1987 io_fail_links(req);
1988 return NULL;
Jens Axboe4d7dd462019-11-20 13:03:52 -07001989}
Jens Axboe2665abf2019-11-05 12:40:47 -07001990
Pavel Begunkov3fa5e0f2020-06-30 15:20:43 +03001991static struct io_kiocb *io_req_find_next(struct io_kiocb *req)
1992{
1993 if (likely(!(req->flags & REQ_F_LINK_HEAD)))
1994 return NULL;
1995 return __io_req_find_next(req);
1996}
1997
Jens Axboe355fb9e2020-10-22 20:19:35 -06001998static int io_req_task_work_add(struct io_kiocb *req)
Jens Axboec2c4c832020-07-01 15:37:11 -06001999{
2000 struct task_struct *tsk = req->task;
2001 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe91989c72020-10-16 09:02:26 -06002002 enum task_work_notify_mode notify;
2003 int ret;
Jens Axboec2c4c832020-07-01 15:37:11 -06002004
Jens Axboe6200b0a2020-09-13 14:38:30 -06002005 if (tsk->flags & PF_EXITING)
2006 return -ESRCH;
2007
Jens Axboec2c4c832020-07-01 15:37:11 -06002008 /*
Jens Axboe0ba9c9e2020-08-06 19:41:50 -06002009 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2010 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2011 * processing task_work. There's no reliable way to tell if TWA_RESUME
2012 * will do the job.
Jens Axboec2c4c832020-07-01 15:37:11 -06002013 */
Jens Axboe91989c72020-10-16 09:02:26 -06002014 notify = TWA_NONE;
Jens Axboe355fb9e2020-10-22 20:19:35 -06002015 if (!(ctx->flags & IORING_SETUP_SQPOLL))
Jens Axboec2c4c832020-07-01 15:37:11 -06002016 notify = TWA_SIGNAL;
2017
Jens Axboe87c43112020-09-30 21:00:14 -06002018 ret = task_work_add(tsk, &req->task_work, notify);
Jens Axboec2c4c832020-07-01 15:37:11 -06002019 if (!ret)
2020 wake_up_process(tsk);
Jens Axboe0ba9c9e2020-08-06 19:41:50 -06002021
Jens Axboec2c4c832020-07-01 15:37:11 -06002022 return ret;
2023}
2024
Jens Axboec40f6372020-06-25 15:39:59 -06002025static void __io_req_task_cancel(struct io_kiocb *req, int error)
2026{
2027 struct io_ring_ctx *ctx = req->ctx;
2028
2029 spin_lock_irq(&ctx->completion_lock);
2030 io_cqring_fill_event(req, error);
2031 io_commit_cqring(ctx);
2032 spin_unlock_irq(&ctx->completion_lock);
2033
2034 io_cqring_ev_posted(ctx);
2035 req_set_fail_links(req);
2036 io_double_put_req(req);
2037}
2038
2039static void io_req_task_cancel(struct callback_head *cb)
2040{
2041 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
Jens Axboe87ceb6a2020-09-14 08:20:12 -06002042 struct io_ring_ctx *ctx = req->ctx;
Jens Axboec40f6372020-06-25 15:39:59 -06002043
2044 __io_req_task_cancel(req, -ECANCELED);
Jens Axboe87ceb6a2020-09-14 08:20:12 -06002045 percpu_ref_put(&ctx->refs);
Jens Axboec40f6372020-06-25 15:39:59 -06002046}
2047
2048static void __io_req_task_submit(struct io_kiocb *req)
2049{
2050 struct io_ring_ctx *ctx = req->ctx;
2051
Jens Axboec40f6372020-06-25 15:39:59 -06002052 if (!__io_sq_thread_acquire_mm(ctx)) {
2053 mutex_lock(&ctx->uring_lock);
Pavel Begunkovc1379e22020-09-30 22:57:56 +03002054 __io_queue_sqe(req, NULL);
Jens Axboec40f6372020-06-25 15:39:59 -06002055 mutex_unlock(&ctx->uring_lock);
Jens Axboe2665abf2019-11-05 12:40:47 -07002056 } else {
Jens Axboec40f6372020-06-25 15:39:59 -06002057 __io_req_task_cancel(req, -EFAULT);
Jens Axboe2665abf2019-11-05 12:40:47 -07002058 }
Jens Axboe9e645e112019-05-10 16:07:28 -06002059}
2060
Jens Axboec40f6372020-06-25 15:39:59 -06002061static void io_req_task_submit(struct callback_head *cb)
2062{
2063 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
Jens Axboe6d816e02020-08-11 08:04:14 -06002064 struct io_ring_ctx *ctx = req->ctx;
Jens Axboec40f6372020-06-25 15:39:59 -06002065
2066 __io_req_task_submit(req);
Jens Axboe6d816e02020-08-11 08:04:14 -06002067 percpu_ref_put(&ctx->refs);
Jens Axboec40f6372020-06-25 15:39:59 -06002068}
2069
2070static void io_req_task_queue(struct io_kiocb *req)
2071{
Jens Axboec40f6372020-06-25 15:39:59 -06002072 int ret;
2073
2074 init_task_work(&req->task_work, io_req_task_submit);
Jens Axboe6d816e02020-08-11 08:04:14 -06002075 percpu_ref_get(&req->ctx->refs);
Jens Axboec40f6372020-06-25 15:39:59 -06002076
Jens Axboe355fb9e2020-10-22 20:19:35 -06002077 ret = io_req_task_work_add(req);
Jens Axboec40f6372020-06-25 15:39:59 -06002078 if (unlikely(ret)) {
Jens Axboec2c4c832020-07-01 15:37:11 -06002079 struct task_struct *tsk;
2080
Jens Axboec40f6372020-06-25 15:39:59 -06002081 init_task_work(&req->task_work, io_req_task_cancel);
2082 tsk = io_wq_get_task(req->ctx->io_wq);
Jens Axboe91989c72020-10-16 09:02:26 -06002083 task_work_add(tsk, &req->task_work, TWA_NONE);
Jens Axboec2c4c832020-07-01 15:37:11 -06002084 wake_up_process(tsk);
Jens Axboec40f6372020-06-25 15:39:59 -06002085 }
Jens Axboec40f6372020-06-25 15:39:59 -06002086}
2087
Pavel Begunkovc3524382020-06-28 12:52:32 +03002088static void io_queue_next(struct io_kiocb *req)
Jackie Liuc69f8db2019-11-09 11:00:08 +08002089{
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03002090 struct io_kiocb *nxt = io_req_find_next(req);
Pavel Begunkov944e58b2019-11-21 23:21:01 +03002091
Pavel Begunkov906a8c32020-06-27 14:04:55 +03002092 if (nxt)
2093 io_req_task_queue(nxt);
Jackie Liuc69f8db2019-11-09 11:00:08 +08002094}
2095
Jens Axboe9e645e112019-05-10 16:07:28 -06002096static void io_free_req(struct io_kiocb *req)
2097{
Pavel Begunkovc3524382020-06-28 12:52:32 +03002098 io_queue_next(req);
Jens Axboe9e645e112019-05-10 16:07:28 -06002099 __io_free_req(req);
Jens Axboee65ef562019-03-12 10:16:44 -06002100}
2101
Pavel Begunkov2d6500d2020-06-28 12:52:33 +03002102struct req_batch {
2103 void *reqs[IO_IOPOLL_BATCH];
2104 int to_free;
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002105
2106 struct task_struct *task;
2107 int task_refs;
Pavel Begunkov2d6500d2020-06-28 12:52:33 +03002108};
2109
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002110static inline void io_init_req_batch(struct req_batch *rb)
Pavel Begunkov7a743e22020-03-03 21:33:13 +03002111{
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002112 rb->to_free = 0;
2113 rb->task_refs = 0;
2114 rb->task = NULL;
2115}
Pavel Begunkov8766dd52020-03-14 00:31:04 +03002116
Pavel Begunkov2d6500d2020-06-28 12:52:33 +03002117static void __io_req_free_batch_flush(struct io_ring_ctx *ctx,
2118 struct req_batch *rb)
2119{
2120 kmem_cache_free_bulk(req_cachep, rb->to_free, rb->reqs);
2121 percpu_ref_put_many(&ctx->refs, rb->to_free);
2122 rb->to_free = 0;
2123}
Pavel Begunkov7a743e22020-03-03 21:33:13 +03002124
Pavel Begunkov2d6500d2020-06-28 12:52:33 +03002125static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
2126 struct req_batch *rb)
2127{
2128 if (rb->to_free)
2129 __io_req_free_batch_flush(ctx, rb);
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002130 if (rb->task) {
Jens Axboed8a6df12020-10-15 16:24:45 -06002131 struct io_uring_task *tctx = rb->task->io_uring;
2132
2133 percpu_counter_sub(&tctx->inflight, rb->task_refs);
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002134 put_task_struct_many(rb->task, rb->task_refs);
2135 rb->task = NULL;
2136 }
Pavel Begunkov2d6500d2020-06-28 12:52:33 +03002137}
2138
2139static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req)
2140{
2141 if (unlikely(io_is_fallback_req(req))) {
2142 io_free_req(req);
2143 return;
2144 }
2145 if (req->flags & REQ_F_LINK_HEAD)
2146 io_queue_next(req);
2147
Jens Axboee3bc8e92020-09-24 08:45:57 -06002148 if (req->task != rb->task) {
Jens Axboe0f212202020-09-13 13:09:39 -06002149 if (rb->task) {
Jens Axboed8a6df12020-10-15 16:24:45 -06002150 struct io_uring_task *tctx = rb->task->io_uring;
2151
2152 percpu_counter_sub(&tctx->inflight, rb->task_refs);
Jens Axboee3bc8e92020-09-24 08:45:57 -06002153 put_task_struct_many(rb->task, rb->task_refs);
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002154 }
Jens Axboee3bc8e92020-09-24 08:45:57 -06002155 rb->task = req->task;
2156 rb->task_refs = 0;
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002157 }
Jens Axboee3bc8e92020-09-24 08:45:57 -06002158 rb->task_refs++;
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002159
Pavel Begunkov4edf20f2020-10-13 09:43:59 +01002160 io_dismantle_req(req);
Pavel Begunkov2d6500d2020-06-28 12:52:33 +03002161 rb->reqs[rb->to_free++] = req;
2162 if (unlikely(rb->to_free == ARRAY_SIZE(rb->reqs)))
2163 __io_req_free_batch_flush(req->ctx, rb);
Pavel Begunkov7a743e22020-03-03 21:33:13 +03002164}
2165
Jens Axboeba816ad2019-09-28 11:36:45 -06002166/*
2167 * Drop reference to request, return next in chain (if there is one) if this
2168 * was the last reference to this request.
2169 */
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03002170static struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
Jens Axboee65ef562019-03-12 10:16:44 -06002171{
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03002172 struct io_kiocb *nxt = NULL;
2173
Jens Axboe2a44f462020-02-25 13:25:41 -07002174 if (refcount_dec_and_test(&req->refs)) {
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03002175 nxt = io_req_find_next(req);
Jens Axboe4d7dd462019-11-20 13:03:52 -07002176 __io_free_req(req);
Jens Axboe2a44f462020-02-25 13:25:41 -07002177 }
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03002178 return nxt;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002179}
2180
Jens Axboe2b188cc2019-01-07 10:46:33 -07002181static void io_put_req(struct io_kiocb *req)
2182{
Jens Axboedef596e2019-01-09 08:59:42 -07002183 if (refcount_dec_and_test(&req->refs))
2184 io_free_req(req);
2185}
2186
Pavel Begunkov216578e2020-10-13 09:44:00 +01002187static void io_put_req_deferred_cb(struct callback_head *cb)
2188{
2189 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
2190
2191 io_free_req(req);
2192}
2193
2194static void io_free_req_deferred(struct io_kiocb *req)
2195{
2196 int ret;
2197
2198 init_task_work(&req->task_work, io_put_req_deferred_cb);
Jens Axboe355fb9e2020-10-22 20:19:35 -06002199 ret = io_req_task_work_add(req);
Pavel Begunkov216578e2020-10-13 09:44:00 +01002200 if (unlikely(ret)) {
2201 struct task_struct *tsk;
2202
2203 tsk = io_wq_get_task(req->ctx->io_wq);
Jens Axboe91989c72020-10-16 09:02:26 -06002204 task_work_add(tsk, &req->task_work, TWA_NONE);
Pavel Begunkov216578e2020-10-13 09:44:00 +01002205 wake_up_process(tsk);
2206 }
2207}
2208
2209static inline void io_put_req_deferred(struct io_kiocb *req, int refs)
2210{
2211 if (refcount_sub_and_test(refs, &req->refs))
2212 io_free_req_deferred(req);
2213}
2214
Pavel Begunkovf4db7182020-06-25 18:20:54 +03002215static struct io_wq_work *io_steal_work(struct io_kiocb *req)
Pavel Begunkov7a743e22020-03-03 21:33:13 +03002216{
Pavel Begunkov6df1db62020-07-03 22:15:06 +03002217 struct io_kiocb *nxt;
Pavel Begunkov7a743e22020-03-03 21:33:13 +03002218
Pavel Begunkovf4db7182020-06-25 18:20:54 +03002219 /*
2220 * A ref is owned by io-wq in which context we're. So, if that's the
2221 * last one, it's safe to steal next work. False negatives are Ok,
2222 * it just will be re-punted async in io_put_work()
2223 */
2224 if (refcount_read(&req->refs) != 1)
2225 return NULL;
2226
Pavel Begunkov9b5f7bd2020-06-29 13:13:00 +03002227 nxt = io_req_find_next(req);
Pavel Begunkov6df1db62020-07-03 22:15:06 +03002228 return nxt ? &nxt->work : NULL;
Pavel Begunkov7a743e22020-03-03 21:33:13 +03002229}
2230
Jens Axboe978db572019-11-14 22:39:04 -07002231static void io_double_put_req(struct io_kiocb *req)
2232{
2233 /* drop both submit and complete references */
2234 if (refcount_sub_and_test(2, &req->refs))
2235 io_free_req(req);
2236}
2237
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07002238static unsigned io_cqring_events(struct io_ring_ctx *ctx, bool noflush)
Jens Axboea3a0e432019-08-20 11:03:11 -06002239{
Jens Axboe84f97dc2019-11-06 11:27:53 -07002240 struct io_rings *rings = ctx->rings;
2241
Jens Axboead3eb2c2019-12-18 17:12:20 -07002242 if (test_bit(0, &ctx->cq_check_overflow)) {
2243 /*
2244 * noflush == true is from the waitqueue handler, just ensure
2245 * we wake up the task, and the next invocation will flush the
2246 * entries. We cannot safely to it from here.
2247 */
2248 if (noflush && !list_empty(&ctx->cq_overflow_list))
2249 return -1U;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07002250
Jens Axboee6c8aa92020-09-28 13:10:13 -06002251 io_cqring_overflow_flush(ctx, false, NULL, NULL);
Jens Axboead3eb2c2019-12-18 17:12:20 -07002252 }
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07002253
Jens Axboea3a0e432019-08-20 11:03:11 -06002254 /* See comment at the top of this file */
2255 smp_rmb();
Jens Axboead3eb2c2019-12-18 17:12:20 -07002256 return ctx->cached_cq_tail - READ_ONCE(rings->cq.head);
Jens Axboea3a0e432019-08-20 11:03:11 -06002257}
2258
Pavel Begunkovfb5ccc92019-10-25 12:31:30 +03002259static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
2260{
2261 struct io_rings *rings = ctx->rings;
2262
2263 /* make sure SQ entry isn't read before tail */
2264 return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
2265}
2266
Pavel Begunkov8ff069b2020-07-16 23:28:04 +03002267static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
Jens Axboee94f1412019-12-19 12:06:02 -07002268{
Pavel Begunkov8ff069b2020-07-16 23:28:04 +03002269 unsigned int cflags;
Jens Axboee94f1412019-12-19 12:06:02 -07002270
Jens Axboebcda7ba2020-02-23 16:42:51 -07002271 cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
2272 cflags |= IORING_CQE_F_BUFFER;
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03002273 req->flags &= ~REQ_F_BUFFER_SELECTED;
Jens Axboebcda7ba2020-02-23 16:42:51 -07002274 kfree(kbuf);
2275 return cflags;
2276}
2277
Pavel Begunkov8ff069b2020-07-16 23:28:04 +03002278static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
2279{
2280 struct io_buffer *kbuf;
2281
2282 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
2283 return io_put_kbuf(req, kbuf);
2284}
2285
Jens Axboe4c6e2772020-07-01 11:29:10 -06002286static inline bool io_run_task_work(void)
2287{
Jens Axboe6200b0a2020-09-13 14:38:30 -06002288 /*
2289 * Not safe to run on exiting task, and the task_work handling will
2290 * not add work to such a task.
2291 */
2292 if (unlikely(current->flags & PF_EXITING))
2293 return false;
Jens Axboe4c6e2772020-07-01 11:29:10 -06002294 if (current->task_works) {
2295 __set_current_state(TASK_RUNNING);
2296 task_work_run();
2297 return true;
2298 }
2299
2300 return false;
2301}
2302
Xiaoguang Wangbbde0172020-06-16 02:06:38 +08002303static void io_iopoll_queue(struct list_head *again)
2304{
2305 struct io_kiocb *req;
2306
2307 do {
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002308 req = list_first_entry(again, struct io_kiocb, inflight_entry);
2309 list_del(&req->inflight_entry);
Pavel Begunkov81b68a52020-07-30 18:43:46 +03002310 __io_complete_rw(req, -EAGAIN, 0, NULL);
Xiaoguang Wangbbde0172020-06-16 02:06:38 +08002311 } while (!list_empty(again));
2312}
2313
Jens Axboedef596e2019-01-09 08:59:42 -07002314/*
2315 * Find and free completed poll iocbs
2316 */
2317static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
2318 struct list_head *done)
2319{
Jens Axboe8237e042019-12-28 10:48:22 -07002320 struct req_batch rb;
Jens Axboedef596e2019-01-09 08:59:42 -07002321 struct io_kiocb *req;
Xiaoguang Wangbbde0172020-06-16 02:06:38 +08002322 LIST_HEAD(again);
2323
2324 /* order with ->result store in io_complete_rw_iopoll() */
2325 smp_rmb();
Jens Axboedef596e2019-01-09 08:59:42 -07002326
Pavel Begunkov5af1d132020-07-18 11:32:52 +03002327 io_init_req_batch(&rb);
Jens Axboedef596e2019-01-09 08:59:42 -07002328 while (!list_empty(done)) {
Jens Axboebcda7ba2020-02-23 16:42:51 -07002329 int cflags = 0;
2330
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002331 req = list_first_entry(done, struct io_kiocb, inflight_entry);
Xiaoguang Wangbbde0172020-06-16 02:06:38 +08002332 if (READ_ONCE(req->result) == -EAGAIN) {
Jens Axboe56450c22020-08-26 18:58:26 -06002333 req->result = 0;
Xiaoguang Wangbbde0172020-06-16 02:06:38 +08002334 req->iopoll_completed = 0;
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002335 list_move_tail(&req->inflight_entry, &again);
Xiaoguang Wangbbde0172020-06-16 02:06:38 +08002336 continue;
2337 }
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002338 list_del(&req->inflight_entry);
Jens Axboedef596e2019-01-09 08:59:42 -07002339
Jens Axboebcda7ba2020-02-23 16:42:51 -07002340 if (req->flags & REQ_F_BUFFER_SELECTED)
Pavel Begunkov8ff069b2020-07-16 23:28:04 +03002341 cflags = io_put_rw_kbuf(req);
Jens Axboebcda7ba2020-02-23 16:42:51 -07002342
2343 __io_cqring_fill_event(req, req->result, cflags);
Jens Axboedef596e2019-01-09 08:59:42 -07002344 (*nr_events)++;
2345
Pavel Begunkovc3524382020-06-28 12:52:32 +03002346 if (refcount_dec_and_test(&req->refs))
Pavel Begunkov2d6500d2020-06-28 12:52:33 +03002347 io_req_free_batch(&rb, req);
Jens Axboedef596e2019-01-09 08:59:42 -07002348 }
Jens Axboedef596e2019-01-09 08:59:42 -07002349
Jens Axboe09bb8392019-03-13 12:39:28 -06002350 io_commit_cqring(ctx);
Xiaoguang Wang32b22442020-03-11 09:26:09 +08002351 if (ctx->flags & IORING_SETUP_SQPOLL)
2352 io_cqring_ev_posted(ctx);
Pavel Begunkov2d6500d2020-06-28 12:52:33 +03002353 io_req_free_batch_finish(ctx, &rb);
Jens Axboedef596e2019-01-09 08:59:42 -07002354
Xiaoguang Wangbbde0172020-06-16 02:06:38 +08002355 if (!list_empty(&again))
2356 io_iopoll_queue(&again);
Bijan Mottahedeh581f9812020-04-03 13:51:33 -07002357}
2358
Jens Axboedef596e2019-01-09 08:59:42 -07002359static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
2360 long min)
2361{
2362 struct io_kiocb *req, *tmp;
2363 LIST_HEAD(done);
2364 bool spin;
2365 int ret;
2366
2367 /*
2368 * Only spin for completions if we don't have multiple devices hanging
2369 * off our complete list, and we're under the requested amount.
2370 */
2371 spin = !ctx->poll_multi_file && *nr_events < min;
2372
2373 ret = 0;
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002374 list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
Jens Axboe9adbd452019-12-20 08:45:55 -07002375 struct kiocb *kiocb = &req->rw.kiocb;
Jens Axboedef596e2019-01-09 08:59:42 -07002376
2377 /*
Bijan Mottahedeh581f9812020-04-03 13:51:33 -07002378 * Move completed and retryable entries to our local lists.
2379 * If we find a request that requires polling, break out
2380 * and complete those lists first, if we have entries there.
Jens Axboedef596e2019-01-09 08:59:42 -07002381 */
Xiaoguang Wang65a65432020-06-11 23:39:36 +08002382 if (READ_ONCE(req->iopoll_completed)) {
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002383 list_move_tail(&req->inflight_entry, &done);
Jens Axboedef596e2019-01-09 08:59:42 -07002384 continue;
2385 }
2386 if (!list_empty(&done))
2387 break;
2388
2389 ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin);
2390 if (ret < 0)
2391 break;
2392
Pavel Begunkov3aadc232020-07-06 17:59:29 +03002393 /* iopoll may have completed current req */
2394 if (READ_ONCE(req->iopoll_completed))
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002395 list_move_tail(&req->inflight_entry, &done);
Pavel Begunkov3aadc232020-07-06 17:59:29 +03002396
Jens Axboedef596e2019-01-09 08:59:42 -07002397 if (ret && spin)
2398 spin = false;
2399 ret = 0;
2400 }
2401
2402 if (!list_empty(&done))
2403 io_iopoll_complete(ctx, nr_events, &done);
2404
2405 return ret;
2406}
2407
2408/*
Brian Gianforcarod195a662019-12-13 03:09:50 -08002409 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
Jens Axboedef596e2019-01-09 08:59:42 -07002410 * non-spinning poll check - we'll still enter the driver poll loop, but only
2411 * as a non-spinning completion check.
2412 */
2413static int io_iopoll_getevents(struct io_ring_ctx *ctx, unsigned int *nr_events,
2414 long min)
2415{
Pavel Begunkov540e32a2020-07-13 23:37:09 +03002416 while (!list_empty(&ctx->iopoll_list) && !need_resched()) {
Jens Axboedef596e2019-01-09 08:59:42 -07002417 int ret;
2418
2419 ret = io_do_iopoll(ctx, nr_events, min);
2420 if (ret < 0)
2421 return ret;
Pavel Begunkoveba0a4d2020-07-06 17:59:30 +03002422 if (*nr_events >= min)
Jens Axboedef596e2019-01-09 08:59:42 -07002423 return 0;
2424 }
2425
2426 return 1;
2427}
2428
2429/*
2430 * We can't just wait for polled events to come to us, we have to actively
2431 * find and complete them.
2432 */
Pavel Begunkovb2edc0a2020-07-07 16:36:22 +03002433static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
Jens Axboedef596e2019-01-09 08:59:42 -07002434{
2435 if (!(ctx->flags & IORING_SETUP_IOPOLL))
2436 return;
2437
2438 mutex_lock(&ctx->uring_lock);
Pavel Begunkov540e32a2020-07-13 23:37:09 +03002439 while (!list_empty(&ctx->iopoll_list)) {
Jens Axboedef596e2019-01-09 08:59:42 -07002440 unsigned int nr_events = 0;
2441
Pavel Begunkovb2edc0a2020-07-07 16:36:22 +03002442 io_do_iopoll(ctx, &nr_events, 0);
Jens Axboe08f54392019-08-21 22:19:11 -06002443
Pavel Begunkovb2edc0a2020-07-07 16:36:22 +03002444 /* let it sleep and repeat later if can't complete a request */
2445 if (nr_events == 0)
2446 break;
Jens Axboe08f54392019-08-21 22:19:11 -06002447 /*
2448 * Ensure we allow local-to-the-cpu processing to take place,
2449 * in this case we need to ensure that we reap all events.
Pavel Begunkov3fcee5a2020-07-06 17:59:31 +03002450 * Also let task_work, etc. to progress by releasing the mutex
Jens Axboe08f54392019-08-21 22:19:11 -06002451 */
Pavel Begunkov3fcee5a2020-07-06 17:59:31 +03002452 if (need_resched()) {
2453 mutex_unlock(&ctx->uring_lock);
2454 cond_resched();
2455 mutex_lock(&ctx->uring_lock);
2456 }
Jens Axboedef596e2019-01-09 08:59:42 -07002457 }
2458 mutex_unlock(&ctx->uring_lock);
2459}
2460
Pavel Begunkov7668b922020-07-07 16:36:21 +03002461static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
Jens Axboedef596e2019-01-09 08:59:42 -07002462{
Pavel Begunkov7668b922020-07-07 16:36:21 +03002463 unsigned int nr_events = 0;
Jens Axboe2b2ed972019-10-25 10:06:15 -06002464 int iters = 0, ret = 0;
Jens Axboedef596e2019-01-09 08:59:42 -07002465
Xiaoguang Wangc7849be2020-02-22 14:46:05 +08002466 /*
2467 * We disallow the app entering submit/complete with polling, but we
2468 * still need to lock the ring to prevent racing with polled issue
2469 * that got punted to a workqueue.
2470 */
2471 mutex_lock(&ctx->uring_lock);
Jens Axboedef596e2019-01-09 08:59:42 -07002472 do {
Jens Axboe500f9fb2019-08-19 12:15:59 -06002473 /*
Jens Axboea3a0e432019-08-20 11:03:11 -06002474 * Don't enter poll loop if we already have events pending.
2475 * If we do, we can potentially be spinning for commands that
2476 * already triggered a CQE (eg in error).
2477 */
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07002478 if (io_cqring_events(ctx, false))
Jens Axboea3a0e432019-08-20 11:03:11 -06002479 break;
2480
2481 /*
Jens Axboe500f9fb2019-08-19 12:15:59 -06002482 * If a submit got punted to a workqueue, we can have the
2483 * application entering polling for a command before it gets
2484 * issued. That app will hold the uring_lock for the duration
2485 * of the poll right here, so we need to take a breather every
2486 * now and then to ensure that the issue has a chance to add
2487 * the poll to the issued list. Otherwise we can spin here
2488 * forever, while the workqueue is stuck trying to acquire the
2489 * very same mutex.
2490 */
2491 if (!(++iters & 7)) {
2492 mutex_unlock(&ctx->uring_lock);
Jens Axboe4c6e2772020-07-01 11:29:10 -06002493 io_run_task_work();
Jens Axboe500f9fb2019-08-19 12:15:59 -06002494 mutex_lock(&ctx->uring_lock);
2495 }
2496
Pavel Begunkov7668b922020-07-07 16:36:21 +03002497 ret = io_iopoll_getevents(ctx, &nr_events, min);
Jens Axboedef596e2019-01-09 08:59:42 -07002498 if (ret <= 0)
2499 break;
2500 ret = 0;
Pavel Begunkov7668b922020-07-07 16:36:21 +03002501 } while (min && !nr_events && !need_resched());
Jens Axboedef596e2019-01-09 08:59:42 -07002502
Jens Axboe500f9fb2019-08-19 12:15:59 -06002503 mutex_unlock(&ctx->uring_lock);
Jens Axboedef596e2019-01-09 08:59:42 -07002504 return ret;
2505}
2506
Jens Axboe491381ce2019-10-17 09:20:46 -06002507static void kiocb_end_write(struct io_kiocb *req)
Jens Axboe2b188cc2019-01-07 10:46:33 -07002508{
Jens Axboe491381ce2019-10-17 09:20:46 -06002509 /*
2510 * Tell lockdep we inherited freeze protection from submission
2511 * thread.
2512 */
2513 if (req->flags & REQ_F_ISREG) {
2514 struct inode *inode = file_inode(req->file);
Jens Axboe2b188cc2019-01-07 10:46:33 -07002515
Jens Axboe491381ce2019-10-17 09:20:46 -06002516 __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE);
Jens Axboe2b188cc2019-01-07 10:46:33 -07002517 }
Jens Axboe491381ce2019-10-17 09:20:46 -06002518 file_end_write(req->file);
Jens Axboe2b188cc2019-01-07 10:46:33 -07002519}
2520
Jens Axboea1d7c392020-06-22 11:09:46 -06002521static void io_complete_rw_common(struct kiocb *kiocb, long res,
2522 struct io_comp_state *cs)
Jens Axboe2b188cc2019-01-07 10:46:33 -07002523{
Jens Axboe9adbd452019-12-20 08:45:55 -07002524 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
Jens Axboebcda7ba2020-02-23 16:42:51 -07002525 int cflags = 0;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002526
Jens Axboe491381ce2019-10-17 09:20:46 -06002527 if (kiocb->ki_flags & IOCB_WRITE)
2528 kiocb_end_write(req);
Jens Axboe2b188cc2019-01-07 10:46:33 -07002529
Jens Axboe4e88d6e2019-12-07 20:59:47 -07002530 if (res != req->result)
2531 req_set_fail_links(req);
Jens Axboebcda7ba2020-02-23 16:42:51 -07002532 if (req->flags & REQ_F_BUFFER_SELECTED)
Pavel Begunkov8ff069b2020-07-16 23:28:04 +03002533 cflags = io_put_rw_kbuf(req);
Jens Axboea1d7c392020-06-22 11:09:46 -06002534 __io_req_complete(req, res, cflags, cs);
Jens Axboeba816ad2019-09-28 11:36:45 -06002535}
2536
Jens Axboeb63534c2020-06-04 11:28:00 -06002537#ifdef CONFIG_BLOCK
2538static bool io_resubmit_prep(struct io_kiocb *req, int error)
2539{
2540 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
2541 ssize_t ret = -ECANCELED;
2542 struct iov_iter iter;
2543 int rw;
2544
2545 if (error) {
2546 ret = error;
2547 goto end_req;
2548 }
2549
2550 switch (req->opcode) {
2551 case IORING_OP_READV:
2552 case IORING_OP_READ_FIXED:
2553 case IORING_OP_READ:
2554 rw = READ;
2555 break;
2556 case IORING_OP_WRITEV:
2557 case IORING_OP_WRITE_FIXED:
2558 case IORING_OP_WRITE:
2559 rw = WRITE;
2560 break;
2561 default:
2562 printk_once(KERN_WARNING "io_uring: bad opcode in resubmit %d\n",
2563 req->opcode);
2564 goto end_req;
2565 }
2566
Jens Axboee8c2bc12020-08-15 18:44:09 -07002567 if (!req->async_data) {
Jens Axboe8f3d7492020-09-14 09:28:14 -06002568 ret = io_import_iovec(rw, req, &iovec, &iter, false);
2569 if (ret < 0)
2570 goto end_req;
2571 ret = io_setup_async_rw(req, iovec, inline_vecs, &iter, false);
2572 if (!ret)
2573 return true;
2574 kfree(iovec);
2575 } else {
Jens Axboeb63534c2020-06-04 11:28:00 -06002576 return true;
Jens Axboe8f3d7492020-09-14 09:28:14 -06002577 }
Jens Axboeb63534c2020-06-04 11:28:00 -06002578end_req:
Jens Axboeb63534c2020-06-04 11:28:00 -06002579 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06002580 io_req_complete(req, ret);
Jens Axboeb63534c2020-06-04 11:28:00 -06002581 return false;
2582}
Jens Axboeb63534c2020-06-04 11:28:00 -06002583#endif
2584
2585static bool io_rw_reissue(struct io_kiocb *req, long res)
2586{
2587#ifdef CONFIG_BLOCK
Jens Axboe355afae2020-09-02 09:30:31 -06002588 umode_t mode = file_inode(req->file)->i_mode;
Jens Axboeb63534c2020-06-04 11:28:00 -06002589 int ret;
2590
Jens Axboe355afae2020-09-02 09:30:31 -06002591 if (!S_ISBLK(mode) && !S_ISREG(mode))
2592 return false;
Jens Axboeb63534c2020-06-04 11:28:00 -06002593 if ((res != -EAGAIN && res != -EOPNOTSUPP) || io_wq_current_is_worker())
2594 return false;
2595
Jens Axboefdee9462020-08-27 16:46:24 -06002596 ret = io_sq_thread_acquire_mm(req->ctx, req);
Jens Axboe6d816e02020-08-11 08:04:14 -06002597
Jens Axboefdee9462020-08-27 16:46:24 -06002598 if (io_resubmit_prep(req, ret)) {
2599 refcount_inc(&req->refs);
2600 io_queue_async_work(req);
Jens Axboeb63534c2020-06-04 11:28:00 -06002601 return true;
Jens Axboefdee9462020-08-27 16:46:24 -06002602 }
2603
Jens Axboeb63534c2020-06-04 11:28:00 -06002604#endif
2605 return false;
2606}
2607
Jens Axboea1d7c392020-06-22 11:09:46 -06002608static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
2609 struct io_comp_state *cs)
2610{
2611 if (!io_rw_reissue(req, res))
2612 io_complete_rw_common(&req->rw.kiocb, res, cs);
Jens Axboeba816ad2019-09-28 11:36:45 -06002613}
2614
2615static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
2616{
Jens Axboe9adbd452019-12-20 08:45:55 -07002617 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
Jens Axboeba816ad2019-09-28 11:36:45 -06002618
Jens Axboea1d7c392020-06-22 11:09:46 -06002619 __io_complete_rw(req, res, res2, NULL);
Jens Axboe2b188cc2019-01-07 10:46:33 -07002620}
2621
Jens Axboedef596e2019-01-09 08:59:42 -07002622static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
2623{
Jens Axboe9adbd452019-12-20 08:45:55 -07002624 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
Jens Axboedef596e2019-01-09 08:59:42 -07002625
Jens Axboe491381ce2019-10-17 09:20:46 -06002626 if (kiocb->ki_flags & IOCB_WRITE)
2627 kiocb_end_write(req);
Jens Axboedef596e2019-01-09 08:59:42 -07002628
Xiaoguang Wang2d7d6792020-06-16 02:06:37 +08002629 if (res != -EAGAIN && res != req->result)
Jens Axboe4e88d6e2019-12-07 20:59:47 -07002630 req_set_fail_links(req);
Xiaoguang Wangbbde0172020-06-16 02:06:38 +08002631
2632 WRITE_ONCE(req->result, res);
2633 /* order with io_poll_complete() checking ->result */
Pavel Begunkovcd664b02020-06-25 12:37:10 +03002634 smp_wmb();
2635 WRITE_ONCE(req->iopoll_completed, 1);
Jens Axboedef596e2019-01-09 08:59:42 -07002636}
2637
2638/*
2639 * After the iocb has been issued, it's safe to be found on the poll list.
2640 * Adding the kiocb to the list AFTER submission ensures that we don't
2641 * find it from a io_iopoll_getevents() thread before the issuer is done
2642 * accessing the kiocb cookie.
2643 */
2644static void io_iopoll_req_issued(struct io_kiocb *req)
2645{
2646 struct io_ring_ctx *ctx = req->ctx;
2647
2648 /*
2649 * Track whether we have multiple files in our lists. This will impact
2650 * how we do polling eventually, not spinning if we're on potentially
2651 * different devices.
2652 */
Pavel Begunkov540e32a2020-07-13 23:37:09 +03002653 if (list_empty(&ctx->iopoll_list)) {
Jens Axboedef596e2019-01-09 08:59:42 -07002654 ctx->poll_multi_file = false;
2655 } else if (!ctx->poll_multi_file) {
2656 struct io_kiocb *list_req;
2657
Pavel Begunkov540e32a2020-07-13 23:37:09 +03002658 list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002659 inflight_entry);
Jens Axboe9adbd452019-12-20 08:45:55 -07002660 if (list_req->file != req->file)
Jens Axboedef596e2019-01-09 08:59:42 -07002661 ctx->poll_multi_file = true;
2662 }
2663
2664 /*
2665 * For fast devices, IO may have already completed. If it has, add
2666 * it to the front so we find it first.
2667 */
Xiaoguang Wang65a65432020-06-11 23:39:36 +08002668 if (READ_ONCE(req->iopoll_completed))
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002669 list_add(&req->inflight_entry, &ctx->iopoll_list);
Jens Axboedef596e2019-01-09 08:59:42 -07002670 else
Pavel Begunkovd21ffe72020-07-13 23:37:10 +03002671 list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
Xiaoguang Wangbdcd3ea2020-02-25 22:12:08 +08002672
2673 if ((ctx->flags & IORING_SETUP_SQPOLL) &&
Jens Axboe534ca6d2020-09-02 13:52:19 -06002674 wq_has_sleeper(&ctx->sq_data->wait))
2675 wake_up(&ctx->sq_data->wait);
Jens Axboedef596e2019-01-09 08:59:42 -07002676}
2677
Pavel Begunkov9f13c352020-05-17 14:13:41 +03002678static void __io_state_file_put(struct io_submit_state *state)
Jens Axboe9a56a232019-01-09 09:06:50 -07002679{
Pavel Begunkov06ef3602020-07-16 23:28:33 +03002680 if (state->has_refs)
2681 fput_many(state->file, state->has_refs);
Pavel Begunkov9f13c352020-05-17 14:13:41 +03002682 state->file = NULL;
2683}
2684
2685static inline void io_state_file_put(struct io_submit_state *state)
2686{
2687 if (state->file)
2688 __io_state_file_put(state);
Jens Axboe9a56a232019-01-09 09:06:50 -07002689}
2690
2691/*
2692 * Get as many references to a file as we have IOs left in this submission,
2693 * assuming most submissions are for one file, or at least that each file
2694 * has more than one submission.
2695 */
Pavel Begunkov8da11c12020-02-24 11:32:44 +03002696static struct file *__io_file_get(struct io_submit_state *state, int fd)
Jens Axboe9a56a232019-01-09 09:06:50 -07002697{
2698 if (!state)
2699 return fget(fd);
2700
2701 if (state->file) {
2702 if (state->fd == fd) {
Pavel Begunkov06ef3602020-07-16 23:28:33 +03002703 state->has_refs--;
Jens Axboe9a56a232019-01-09 09:06:50 -07002704 return state->file;
2705 }
Pavel Begunkov9f13c352020-05-17 14:13:41 +03002706 __io_state_file_put(state);
Jens Axboe9a56a232019-01-09 09:06:50 -07002707 }
2708 state->file = fget_many(fd, state->ios_left);
2709 if (!state->file)
2710 return NULL;
2711
2712 state->fd = fd;
Pavel Begunkov71b547c2020-10-10 18:34:09 +01002713 state->has_refs = state->ios_left - 1;
Jens Axboe9a56a232019-01-09 09:06:50 -07002714 return state->file;
2715}
2716
Jens Axboe4503b762020-06-01 10:00:27 -06002717static bool io_bdev_nowait(struct block_device *bdev)
2718{
2719#ifdef CONFIG_BLOCK
Jeffle Xu9ba0d0c2020-10-19 16:59:42 +08002720 return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
Jens Axboe4503b762020-06-01 10:00:27 -06002721#else
2722 return true;
2723#endif
2724}
2725
Jens Axboe2b188cc2019-01-07 10:46:33 -07002726/*
2727 * If we tracked the file through the SCM inflight mechanism, we could support
2728 * any file. For now, just ensure that anything potentially problematic is done
2729 * inline.
2730 */
Jens Axboeaf197f52020-04-28 13:15:06 -06002731static bool io_file_supports_async(struct file *file, int rw)
Jens Axboe2b188cc2019-01-07 10:46:33 -07002732{
2733 umode_t mode = file_inode(file)->i_mode;
2734
Jens Axboe4503b762020-06-01 10:00:27 -06002735 if (S_ISBLK(mode)) {
2736 if (io_bdev_nowait(file->f_inode->i_bdev))
2737 return true;
2738 return false;
2739 }
2740 if (S_ISCHR(mode) || S_ISSOCK(mode))
Jens Axboe2b188cc2019-01-07 10:46:33 -07002741 return true;
Jens Axboe4503b762020-06-01 10:00:27 -06002742 if (S_ISREG(mode)) {
2743 if (io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
2744 file->f_op != &io_uring_fops)
2745 return true;
2746 return false;
2747 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07002748
Jens Axboec5b85622020-06-09 19:23:05 -06002749 /* any ->read/write should understand O_NONBLOCK */
2750 if (file->f_flags & O_NONBLOCK)
2751 return true;
2752
Jens Axboeaf197f52020-04-28 13:15:06 -06002753 if (!(file->f_mode & FMODE_NOWAIT))
2754 return false;
2755
2756 if (rw == READ)
2757 return file->f_op->read_iter != NULL;
2758
2759 return file->f_op->write_iter != NULL;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002760}
2761
Pavel Begunkova88fc402020-09-30 22:57:53 +03002762static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboe2b188cc2019-01-07 10:46:33 -07002763{
Jens Axboedef596e2019-01-09 08:59:42 -07002764 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe9adbd452019-12-20 08:45:55 -07002765 struct kiocb *kiocb = &req->rw.kiocb;
Jens Axboe09bb8392019-03-13 12:39:28 -06002766 unsigned ioprio;
2767 int ret;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002768
Jens Axboe491381ce2019-10-17 09:20:46 -06002769 if (S_ISREG(file_inode(req->file)->i_mode))
2770 req->flags |= REQ_F_ISREG;
2771
Jens Axboe2b188cc2019-01-07 10:46:33 -07002772 kiocb->ki_pos = READ_ONCE(sqe->off);
Jens Axboeba042912019-12-25 16:33:42 -07002773 if (kiocb->ki_pos == -1 && !(req->file->f_mode & FMODE_STREAM)) {
2774 req->flags |= REQ_F_CUR_POS;
2775 kiocb->ki_pos = req->file->f_pos;
2776 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07002777 kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
Pavel Begunkov3e577dc2020-02-01 03:58:42 +03002778 kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
2779 ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
2780 if (unlikely(ret))
2781 return ret;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002782
2783 ioprio = READ_ONCE(sqe->ioprio);
2784 if (ioprio) {
2785 ret = ioprio_check_cap(ioprio);
2786 if (ret)
Jens Axboe09bb8392019-03-13 12:39:28 -06002787 return ret;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002788
2789 kiocb->ki_ioprio = ioprio;
2790 } else
2791 kiocb->ki_ioprio = get_current_ioprio();
2792
Stefan Bühler8449eed2019-04-27 20:34:19 +02002793 /* don't allow async punt if RWF_NOWAIT was requested */
Jens Axboec5b85622020-06-09 19:23:05 -06002794 if (kiocb->ki_flags & IOCB_NOWAIT)
Stefan Bühler8449eed2019-04-27 20:34:19 +02002795 req->flags |= REQ_F_NOWAIT;
2796
Jens Axboedef596e2019-01-09 08:59:42 -07002797 if (ctx->flags & IORING_SETUP_IOPOLL) {
Jens Axboedef596e2019-01-09 08:59:42 -07002798 if (!(kiocb->ki_flags & IOCB_DIRECT) ||
2799 !kiocb->ki_filp->f_op->iopoll)
Jens Axboe09bb8392019-03-13 12:39:28 -06002800 return -EOPNOTSUPP;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002801
Jens Axboedef596e2019-01-09 08:59:42 -07002802 kiocb->ki_flags |= IOCB_HIPRI;
2803 kiocb->ki_complete = io_complete_rw_iopoll;
Xiaoguang Wang65a65432020-06-11 23:39:36 +08002804 req->iopoll_completed = 0;
Jens Axboedef596e2019-01-09 08:59:42 -07002805 } else {
Jens Axboe09bb8392019-03-13 12:39:28 -06002806 if (kiocb->ki_flags & IOCB_HIPRI)
2807 return -EINVAL;
Jens Axboedef596e2019-01-09 08:59:42 -07002808 kiocb->ki_complete = io_complete_rw;
2809 }
Jens Axboe9adbd452019-12-20 08:45:55 -07002810
Jens Axboe3529d8c2019-12-19 18:24:38 -07002811 req->rw.addr = READ_ONCE(sqe->addr);
2812 req->rw.len = READ_ONCE(sqe->len);
Bijan Mottahedeh4f4eeba2020-05-19 14:52:49 -07002813 req->buf_index = READ_ONCE(sqe->buf_index);
Jens Axboe2b188cc2019-01-07 10:46:33 -07002814 return 0;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002815}
2816
2817static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
2818{
2819 switch (ret) {
2820 case -EIOCBQUEUED:
2821 break;
2822 case -ERESTARTSYS:
2823 case -ERESTARTNOINTR:
2824 case -ERESTARTNOHAND:
2825 case -ERESTART_RESTARTBLOCK:
2826 /*
2827 * We can't just restart the syscall, since previously
2828 * submitted sqes may already be in progress. Just fail this
2829 * IO with EINTR.
2830 */
2831 ret = -EINTR;
Gustavo A. R. Silvadf561f662020-08-23 17:36:59 -05002832 fallthrough;
Jens Axboe2b188cc2019-01-07 10:46:33 -07002833 default:
2834 kiocb->ki_complete(kiocb, ret, 0);
2835 }
2836}
2837
Jens Axboea1d7c392020-06-22 11:09:46 -06002838static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
2839 struct io_comp_state *cs)
Jens Axboeba816ad2019-09-28 11:36:45 -06002840{
Jens Axboeba042912019-12-25 16:33:42 -07002841 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
Jens Axboee8c2bc12020-08-15 18:44:09 -07002842 struct io_async_rw *io = req->async_data;
Jens Axboeba042912019-12-25 16:33:42 -07002843
Jens Axboe227c0c92020-08-13 11:51:40 -06002844 /* add previously done IO, if any */
Jens Axboee8c2bc12020-08-15 18:44:09 -07002845 if (io && io->bytes_done > 0) {
Jens Axboe227c0c92020-08-13 11:51:40 -06002846 if (ret < 0)
Jens Axboee8c2bc12020-08-15 18:44:09 -07002847 ret = io->bytes_done;
Jens Axboe227c0c92020-08-13 11:51:40 -06002848 else
Jens Axboee8c2bc12020-08-15 18:44:09 -07002849 ret += io->bytes_done;
Jens Axboe227c0c92020-08-13 11:51:40 -06002850 }
2851
Jens Axboeba042912019-12-25 16:33:42 -07002852 if (req->flags & REQ_F_CUR_POS)
2853 req->file->f_pos = kiocb->ki_pos;
Pavel Begunkovbcaec082020-02-24 11:30:18 +03002854 if (ret >= 0 && kiocb->ki_complete == io_complete_rw)
Jens Axboea1d7c392020-06-22 11:09:46 -06002855 __io_complete_rw(req, ret, 0, cs);
Jens Axboeba816ad2019-09-28 11:36:45 -06002856 else
2857 io_rw_done(kiocb, ret);
2858}
2859
Jens Axboe9adbd452019-12-20 08:45:55 -07002860static ssize_t io_import_fixed(struct io_kiocb *req, int rw,
Pavel Begunkov7d009162019-11-25 23:14:40 +03002861 struct iov_iter *iter)
Jens Axboeedafcce2019-01-09 09:16:05 -07002862{
Jens Axboe9adbd452019-12-20 08:45:55 -07002863 struct io_ring_ctx *ctx = req->ctx;
2864 size_t len = req->rw.len;
Jens Axboeedafcce2019-01-09 09:16:05 -07002865 struct io_mapped_ubuf *imu;
Pavel Begunkov4be1c612020-09-06 00:45:48 +03002866 u16 index, buf_index = req->buf_index;
Jens Axboeedafcce2019-01-09 09:16:05 -07002867 size_t offset;
2868 u64 buf_addr;
2869
Jens Axboeedafcce2019-01-09 09:16:05 -07002870 if (unlikely(buf_index >= ctx->nr_user_bufs))
2871 return -EFAULT;
Jens Axboeedafcce2019-01-09 09:16:05 -07002872 index = array_index_nospec(buf_index, ctx->nr_user_bufs);
2873 imu = &ctx->user_bufs[index];
Jens Axboe9adbd452019-12-20 08:45:55 -07002874 buf_addr = req->rw.addr;
Jens Axboeedafcce2019-01-09 09:16:05 -07002875
2876 /* overflow */
2877 if (buf_addr + len < buf_addr)
2878 return -EFAULT;
2879 /* not inside the mapped region */
2880 if (buf_addr < imu->ubuf || buf_addr + len > imu->ubuf + imu->len)
2881 return -EFAULT;
2882
2883 /*
2884 * May not be a start of buffer, set size appropriately
2885 * and advance us to the beginning.
2886 */
2887 offset = buf_addr - imu->ubuf;
2888 iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
Jens Axboebd11b3a2019-07-20 08:37:31 -06002889
2890 if (offset) {
2891 /*
2892 * Don't use iov_iter_advance() here, as it's really slow for
2893 * using the latter parts of a big fixed buffer - it iterates
2894 * over each segment manually. We can cheat a bit here, because
2895 * we know that:
2896 *
2897 * 1) it's a BVEC iter, we set it up
2898 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2899 * first and last bvec
2900 *
2901 * So just find our index, and adjust the iterator afterwards.
2902 * If the offset is within the first bvec (or the whole first
2903 * bvec, just use iov_iter_advance(). This makes it easier
2904 * since we can just skip the first segment, which may not
2905 * be PAGE_SIZE aligned.
2906 */
2907 const struct bio_vec *bvec = imu->bvec;
2908
2909 if (offset <= bvec->bv_len) {
2910 iov_iter_advance(iter, offset);
2911 } else {
2912 unsigned long seg_skip;
2913
2914 /* skip first vec */
2915 offset -= bvec->bv_len;
2916 seg_skip = 1 + (offset >> PAGE_SHIFT);
2917
2918 iter->bvec = bvec + seg_skip;
2919 iter->nr_segs -= seg_skip;
Aleix Roca Nonell99c79f62019-08-15 14:03:22 +02002920 iter->count -= bvec->bv_len + offset;
Jens Axboebd11b3a2019-07-20 08:37:31 -06002921 iter->iov_offset = offset & ~PAGE_MASK;
Jens Axboebd11b3a2019-07-20 08:37:31 -06002922 }
2923 }
2924
Jens Axboe5e559562019-11-13 16:12:46 -07002925 return len;
Jens Axboeedafcce2019-01-09 09:16:05 -07002926}
2927
Jens Axboebcda7ba2020-02-23 16:42:51 -07002928static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
2929{
2930 if (needs_lock)
2931 mutex_unlock(&ctx->uring_lock);
2932}
2933
2934static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
2935{
2936 /*
2937 * "Normal" inline submissions always hold the uring_lock, since we
2938 * grab it from the system call. Same is true for the SQPOLL offload.
2939 * The only exception is when we've detached the request and issue it
2940 * from an async worker thread, grab the lock for that case.
2941 */
2942 if (needs_lock)
2943 mutex_lock(&ctx->uring_lock);
2944}
2945
2946static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
2947 int bgid, struct io_buffer *kbuf,
2948 bool needs_lock)
2949{
2950 struct io_buffer *head;
2951
2952 if (req->flags & REQ_F_BUFFER_SELECTED)
2953 return kbuf;
2954
2955 io_ring_submit_lock(req->ctx, needs_lock);
2956
2957 lockdep_assert_held(&req->ctx->uring_lock);
2958
2959 head = idr_find(&req->ctx->io_buffer_idr, bgid);
2960 if (head) {
2961 if (!list_empty(&head->list)) {
2962 kbuf = list_last_entry(&head->list, struct io_buffer,
2963 list);
2964 list_del(&kbuf->list);
2965 } else {
2966 kbuf = head;
2967 idr_remove(&req->ctx->io_buffer_idr, bgid);
2968 }
2969 if (*len > kbuf->len)
2970 *len = kbuf->len;
2971 } else {
2972 kbuf = ERR_PTR(-ENOBUFS);
2973 }
2974
2975 io_ring_submit_unlock(req->ctx, needs_lock);
2976
2977 return kbuf;
2978}
2979
Jens Axboe4d954c22020-02-27 07:31:19 -07002980static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
2981 bool needs_lock)
2982{
2983 struct io_buffer *kbuf;
Bijan Mottahedeh4f4eeba2020-05-19 14:52:49 -07002984 u16 bgid;
Jens Axboe4d954c22020-02-27 07:31:19 -07002985
2986 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
Bijan Mottahedeh4f4eeba2020-05-19 14:52:49 -07002987 bgid = req->buf_index;
Jens Axboe4d954c22020-02-27 07:31:19 -07002988 kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
2989 if (IS_ERR(kbuf))
2990 return kbuf;
2991 req->rw.addr = (u64) (unsigned long) kbuf;
2992 req->flags |= REQ_F_BUFFER_SELECTED;
2993 return u64_to_user_ptr(kbuf->addr);
2994}
2995
2996#ifdef CONFIG_COMPAT
2997static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
2998 bool needs_lock)
2999{
3000 struct compat_iovec __user *uiov;
3001 compat_ssize_t clen;
3002 void __user *buf;
3003 ssize_t len;
3004
3005 uiov = u64_to_user_ptr(req->rw.addr);
3006 if (!access_ok(uiov, sizeof(*uiov)))
3007 return -EFAULT;
3008 if (__get_user(clen, &uiov->iov_len))
3009 return -EFAULT;
3010 if (clen < 0)
3011 return -EINVAL;
3012
3013 len = clen;
3014 buf = io_rw_buffer_select(req, &len, needs_lock);
3015 if (IS_ERR(buf))
3016 return PTR_ERR(buf);
3017 iov[0].iov_base = buf;
3018 iov[0].iov_len = (compat_size_t) len;
3019 return 0;
3020}
3021#endif
3022
3023static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
3024 bool needs_lock)
3025{
3026 struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
3027 void __user *buf;
3028 ssize_t len;
3029
3030 if (copy_from_user(iov, uiov, sizeof(*uiov)))
3031 return -EFAULT;
3032
3033 len = iov[0].iov_len;
3034 if (len < 0)
3035 return -EINVAL;
3036 buf = io_rw_buffer_select(req, &len, needs_lock);
3037 if (IS_ERR(buf))
3038 return PTR_ERR(buf);
3039 iov[0].iov_base = buf;
3040 iov[0].iov_len = len;
3041 return 0;
3042}
3043
3044static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
3045 bool needs_lock)
3046{
Jens Axboedddb3e22020-06-04 11:27:01 -06003047 if (req->flags & REQ_F_BUFFER_SELECTED) {
3048 struct io_buffer *kbuf;
3049
3050 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
3051 iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
3052 iov[0].iov_len = kbuf->len;
Jens Axboe4d954c22020-02-27 07:31:19 -07003053 return 0;
Jens Axboedddb3e22020-06-04 11:27:01 -06003054 }
Jens Axboe4d954c22020-02-27 07:31:19 -07003055 if (!req->rw.len)
3056 return 0;
3057 else if (req->rw.len > 1)
3058 return -EINVAL;
3059
3060#ifdef CONFIG_COMPAT
3061 if (req->ctx->compat)
3062 return io_compat_import(req, iov, needs_lock);
3063#endif
3064
3065 return __io_iov_buffer_select(req, iov, needs_lock);
3066}
3067
Jens Axboe8452fd02020-08-18 13:58:33 -07003068static ssize_t __io_import_iovec(int rw, struct io_kiocb *req,
3069 struct iovec **iovec, struct iov_iter *iter,
3070 bool needs_lock)
Jens Axboe2b188cc2019-01-07 10:46:33 -07003071{
Jens Axboe9adbd452019-12-20 08:45:55 -07003072 void __user *buf = u64_to_user_ptr(req->rw.addr);
3073 size_t sqe_len = req->rw.len;
Jens Axboe4d954c22020-02-27 07:31:19 -07003074 ssize_t ret;
Jens Axboeedafcce2019-01-09 09:16:05 -07003075 u8 opcode;
3076
Jens Axboed625c6e2019-12-17 19:53:05 -07003077 opcode = req->opcode;
Pavel Begunkov7d009162019-11-25 23:14:40 +03003078 if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
Jens Axboeedafcce2019-01-09 09:16:05 -07003079 *iovec = NULL;
Jens Axboe9adbd452019-12-20 08:45:55 -07003080 return io_import_fixed(req, rw, iter);
Jens Axboeedafcce2019-01-09 09:16:05 -07003081 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07003082
Jens Axboebcda7ba2020-02-23 16:42:51 -07003083 /* buffer index only valid with fixed read/write, or buffer select */
Bijan Mottahedeh4f4eeba2020-05-19 14:52:49 -07003084 if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
Jens Axboe9adbd452019-12-20 08:45:55 -07003085 return -EINVAL;
3086
Jens Axboe3a6820f2019-12-22 15:19:35 -07003087 if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
Jens Axboebcda7ba2020-02-23 16:42:51 -07003088 if (req->flags & REQ_F_BUFFER_SELECT) {
Jens Axboe4d954c22020-02-27 07:31:19 -07003089 buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
Pavel Begunkov867a23e2020-08-20 11:34:39 +03003090 if (IS_ERR(buf))
Jens Axboe4d954c22020-02-27 07:31:19 -07003091 return PTR_ERR(buf);
Jens Axboe3f9d6442020-03-11 12:27:04 -06003092 req->rw.len = sqe_len;
Jens Axboebcda7ba2020-02-23 16:42:51 -07003093 }
3094
Jens Axboe3a6820f2019-12-22 15:19:35 -07003095 ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
3096 *iovec = NULL;
Jens Axboe3a901592020-02-25 17:48:55 -07003097 return ret < 0 ? ret : sqe_len;
Jens Axboe3a6820f2019-12-22 15:19:35 -07003098 }
3099
Jens Axboe4d954c22020-02-27 07:31:19 -07003100 if (req->flags & REQ_F_BUFFER_SELECT) {
3101 ret = io_iov_buffer_select(req, *iovec, needs_lock);
Jens Axboe3f9d6442020-03-11 12:27:04 -06003102 if (!ret) {
3103 ret = (*iovec)->iov_len;
3104 iov_iter_init(iter, rw, *iovec, 1, ret);
3105 }
Jens Axboe4d954c22020-02-27 07:31:19 -07003106 *iovec = NULL;
3107 return ret;
3108 }
3109
Christoph Hellwig89cd35c2020-09-25 06:51:41 +02003110 return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
3111 req->ctx->compat);
Jens Axboe2b188cc2019-01-07 10:46:33 -07003112}
3113
Jens Axboe8452fd02020-08-18 13:58:33 -07003114static ssize_t io_import_iovec(int rw, struct io_kiocb *req,
3115 struct iovec **iovec, struct iov_iter *iter,
3116 bool needs_lock)
3117{
Jens Axboee8c2bc12020-08-15 18:44:09 -07003118 struct io_async_rw *iorw = req->async_data;
3119
3120 if (!iorw)
Jens Axboe8452fd02020-08-18 13:58:33 -07003121 return __io_import_iovec(rw, req, iovec, iter, needs_lock);
3122 *iovec = NULL;
Jens Axboee8c2bc12020-08-15 18:44:09 -07003123 return iov_iter_count(&iorw->iter);
Jens Axboe8452fd02020-08-18 13:58:33 -07003124}
3125
Jens Axboe0fef9482020-08-26 10:36:20 -06003126static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
3127{
Pavel Begunkov5b09e372020-09-30 22:57:15 +03003128 return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
Jens Axboe0fef9482020-08-26 10:36:20 -06003129}
3130
Jens Axboe32960612019-09-23 11:05:34 -06003131/*
3132 * For files that don't have ->read_iter() and ->write_iter(), handle them
3133 * by looping over ->read() or ->write() manually.
3134 */
Jens Axboe4017eb92020-10-22 14:14:12 -06003135static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
Jens Axboe32960612019-09-23 11:05:34 -06003136{
Jens Axboe4017eb92020-10-22 14:14:12 -06003137 struct kiocb *kiocb = &req->rw.kiocb;
3138 struct file *file = req->file;
Jens Axboe32960612019-09-23 11:05:34 -06003139 ssize_t ret = 0;
3140
3141 /*
3142 * Don't support polled IO through this interface, and we can't
3143 * support non-blocking either. For the latter, this just causes
3144 * the kiocb to be handled from an async context.
3145 */
3146 if (kiocb->ki_flags & IOCB_HIPRI)
3147 return -EOPNOTSUPP;
3148 if (kiocb->ki_flags & IOCB_NOWAIT)
3149 return -EAGAIN;
3150
3151 while (iov_iter_count(iter)) {
Pavel Begunkov311ae9e2019-11-24 11:58:24 +03003152 struct iovec iovec;
Jens Axboe32960612019-09-23 11:05:34 -06003153 ssize_t nr;
3154
Pavel Begunkov311ae9e2019-11-24 11:58:24 +03003155 if (!iov_iter_is_bvec(iter)) {
3156 iovec = iov_iter_iovec(iter);
3157 } else {
Jens Axboe4017eb92020-10-22 14:14:12 -06003158 iovec.iov_base = u64_to_user_ptr(req->rw.addr);
3159 iovec.iov_len = req->rw.len;
Pavel Begunkov311ae9e2019-11-24 11:58:24 +03003160 }
3161
Jens Axboe32960612019-09-23 11:05:34 -06003162 if (rw == READ) {
3163 nr = file->f_op->read(file, iovec.iov_base,
Jens Axboe0fef9482020-08-26 10:36:20 -06003164 iovec.iov_len, io_kiocb_ppos(kiocb));
Jens Axboe32960612019-09-23 11:05:34 -06003165 } else {
3166 nr = file->f_op->write(file, iovec.iov_base,
Jens Axboe0fef9482020-08-26 10:36:20 -06003167 iovec.iov_len, io_kiocb_ppos(kiocb));
Jens Axboe32960612019-09-23 11:05:34 -06003168 }
3169
3170 if (nr < 0) {
3171 if (!ret)
3172 ret = nr;
3173 break;
3174 }
3175 ret += nr;
3176 if (nr != iovec.iov_len)
3177 break;
Jens Axboe4017eb92020-10-22 14:14:12 -06003178 req->rw.len -= nr;
3179 req->rw.addr += nr;
Jens Axboe32960612019-09-23 11:05:34 -06003180 iov_iter_advance(iter, nr);
3181 }
3182
3183 return ret;
3184}
3185
Jens Axboeff6165b2020-08-13 09:47:43 -06003186static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
3187 const struct iovec *fast_iov, struct iov_iter *iter)
Jens Axboef67676d2019-12-02 11:03:47 -07003188{
Jens Axboee8c2bc12020-08-15 18:44:09 -07003189 struct io_async_rw *rw = req->async_data;
Pavel Begunkovb64e3442020-07-13 22:59:18 +03003190
Jens Axboeff6165b2020-08-13 09:47:43 -06003191 memcpy(&rw->iter, iter, sizeof(*iter));
Pavel Begunkovafb87652020-09-06 00:45:46 +03003192 rw->free_iovec = iovec;
Jens Axboe227c0c92020-08-13 11:51:40 -06003193 rw->bytes_done = 0;
Jens Axboeff6165b2020-08-13 09:47:43 -06003194 /* can only be fixed buffers, no need to do anything */
3195 if (iter->type == ITER_BVEC)
3196 return;
Pavel Begunkovb64e3442020-07-13 22:59:18 +03003197 if (!iovec) {
Jens Axboeff6165b2020-08-13 09:47:43 -06003198 unsigned iov_off = 0;
3199
3200 rw->iter.iov = rw->fast_iov;
3201 if (iter->iov != fast_iov) {
3202 iov_off = iter->iov - fast_iov;
3203 rw->iter.iov += iov_off;
3204 }
3205 if (rw->fast_iov != fast_iov)
3206 memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
Xiaoguang Wang45097da2020-04-08 22:29:58 +08003207 sizeof(struct iovec) * iter->nr_segs);
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03003208 } else {
3209 req->flags |= REQ_F_NEED_CLEANUP;
Jens Axboef67676d2019-12-02 11:03:47 -07003210 }
3211}
3212
Jens Axboee8c2bc12020-08-15 18:44:09 -07003213static inline int __io_alloc_async_data(struct io_kiocb *req)
Xiaoguang Wang3d9932a2020-03-27 15:36:52 +08003214{
Jens Axboee8c2bc12020-08-15 18:44:09 -07003215 WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
3216 req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
3217 return req->async_data == NULL;
Xiaoguang Wang3d9932a2020-03-27 15:36:52 +08003218}
3219
Jens Axboee8c2bc12020-08-15 18:44:09 -07003220static int io_alloc_async_data(struct io_kiocb *req)
Jens Axboef67676d2019-12-02 11:03:47 -07003221{
Jens Axboee8c2bc12020-08-15 18:44:09 -07003222 if (!io_op_defs[req->opcode].needs_async_data)
Jens Axboed3656342019-12-18 09:50:26 -07003223 return 0;
Xiaoguang Wang3d9932a2020-03-27 15:36:52 +08003224
Jens Axboee8c2bc12020-08-15 18:44:09 -07003225 return __io_alloc_async_data(req);
Jens Axboeb7bb4f72019-12-15 22:13:43 -07003226}
3227
Jens Axboeff6165b2020-08-13 09:47:43 -06003228static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
3229 const struct iovec *fast_iov,
Jens Axboe227c0c92020-08-13 11:51:40 -06003230 struct iov_iter *iter, bool force)
Jens Axboeb7bb4f72019-12-15 22:13:43 -07003231{
Jens Axboee8c2bc12020-08-15 18:44:09 -07003232 if (!force && !io_op_defs[req->opcode].needs_async_data)
Jens Axboe74566df2020-01-13 19:23:24 -07003233 return 0;
Jens Axboee8c2bc12020-08-15 18:44:09 -07003234 if (!req->async_data) {
3235 if (__io_alloc_async_data(req))
Jens Axboe5d204bc2020-01-31 12:06:52 -07003236 return -ENOMEM;
Jens Axboeb7bb4f72019-12-15 22:13:43 -07003237
Jens Axboeff6165b2020-08-13 09:47:43 -06003238 io_req_map_rw(req, iovec, fast_iov, iter);
Jens Axboe5d204bc2020-01-31 12:06:52 -07003239 }
Jens Axboeb7bb4f72019-12-15 22:13:43 -07003240 return 0;
Jens Axboef67676d2019-12-02 11:03:47 -07003241}
3242
Pavel Begunkov73debe62020-09-30 22:57:54 +03003243static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
Pavel Begunkovc3e330a2020-07-13 22:59:19 +03003244{
Jens Axboee8c2bc12020-08-15 18:44:09 -07003245 struct io_async_rw *iorw = req->async_data;
Pavel Begunkovf4bff102020-09-06 00:45:45 +03003246 struct iovec *iov = iorw->fast_iov;
Pavel Begunkovc3e330a2020-07-13 22:59:19 +03003247 ssize_t ret;
3248
Pavel Begunkov73debe62020-09-30 22:57:54 +03003249 ret = __io_import_iovec(rw, req, &iov, &iorw->iter, false);
Pavel Begunkovc3e330a2020-07-13 22:59:19 +03003250 if (unlikely(ret < 0))
3251 return ret;
3252
Pavel Begunkovab0b1962020-09-06 00:45:47 +03003253 iorw->bytes_done = 0;
3254 iorw->free_iovec = iov;
3255 if (iov)
3256 req->flags |= REQ_F_NEED_CLEANUP;
Pavel Begunkovc3e330a2020-07-13 22:59:19 +03003257 return 0;
3258}
3259
Pavel Begunkov73debe62020-09-30 22:57:54 +03003260static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboef67676d2019-12-02 11:03:47 -07003261{
3262 ssize_t ret;
3263
Pavel Begunkova88fc402020-09-30 22:57:53 +03003264 ret = io_prep_rw(req, sqe);
Jens Axboe3529d8c2019-12-19 18:24:38 -07003265 if (ret)
3266 return ret;
Jens Axboef67676d2019-12-02 11:03:47 -07003267
Jens Axboe3529d8c2019-12-19 18:24:38 -07003268 if (unlikely(!(req->file->f_mode & FMODE_READ)))
3269 return -EBADF;
Jens Axboef67676d2019-12-02 11:03:47 -07003270
Pavel Begunkov5f798be2020-02-08 13:28:02 +03003271 /* either don't need iovec imported or already have it */
Pavel Begunkov2d199892020-09-30 22:57:35 +03003272 if (!req->async_data)
Jens Axboe3529d8c2019-12-19 18:24:38 -07003273 return 0;
Pavel Begunkov73debe62020-09-30 22:57:54 +03003274 return io_rw_prep_async(req, READ);
Jens Axboef67676d2019-12-02 11:03:47 -07003275}
3276
Jens Axboec1dd91d2020-08-03 16:43:59 -06003277/*
3278 * This is our waitqueue callback handler, registered through lock_page_async()
3279 * when we initially tried to do the IO with the iocb armed our waitqueue.
3280 * This gets called when the page is unlocked, and we generally expect that to
3281 * happen when the page IO is completed and the page is now uptodate. This will
3282 * queue a task_work based retry of the operation, attempting to copy the data
3283 * again. If the latter fails because the page was NOT uptodate, then we will
3284 * do a thread based blocking retry of the operation. That's the unexpected
3285 * slow path.
3286 */
Jens Axboebcf5a062020-05-22 09:24:42 -06003287static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
3288 int sync, void *arg)
3289{
3290 struct wait_page_queue *wpq;
3291 struct io_kiocb *req = wait->private;
Jens Axboebcf5a062020-05-22 09:24:42 -06003292 struct wait_page_key *key = arg;
Jens Axboebcf5a062020-05-22 09:24:42 -06003293 int ret;
3294
3295 wpq = container_of(wait, struct wait_page_queue, wait);
3296
Linus Torvaldscdc8fcb2020-08-03 13:01:22 -07003297 if (!wake_page_match(wpq, key))
3298 return 0;
3299
Hao Xuc8d317a2020-09-29 20:00:45 +08003300 req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
Jens Axboebcf5a062020-05-22 09:24:42 -06003301 list_del_init(&wait->entry);
3302
Pavel Begunkove7375122020-07-12 20:42:04 +03003303 init_task_work(&req->task_work, io_req_task_submit);
Jens Axboe6d816e02020-08-11 08:04:14 -06003304 percpu_ref_get(&req->ctx->refs);
3305
Jens Axboebcf5a062020-05-22 09:24:42 -06003306 /* submit ref gets dropped, acquire a new one */
3307 refcount_inc(&req->refs);
Jens Axboe355fb9e2020-10-22 20:19:35 -06003308 ret = io_req_task_work_add(req);
Jens Axboebcf5a062020-05-22 09:24:42 -06003309 if (unlikely(ret)) {
Jens Axboec2c4c832020-07-01 15:37:11 -06003310 struct task_struct *tsk;
3311
Jens Axboebcf5a062020-05-22 09:24:42 -06003312 /* queue just for cancelation */
Pavel Begunkove7375122020-07-12 20:42:04 +03003313 init_task_work(&req->task_work, io_req_task_cancel);
Jens Axboebcf5a062020-05-22 09:24:42 -06003314 tsk = io_wq_get_task(req->ctx->io_wq);
Jens Axboe91989c72020-10-16 09:02:26 -06003315 task_work_add(tsk, &req->task_work, TWA_NONE);
Jens Axboec2c4c832020-07-01 15:37:11 -06003316 wake_up_process(tsk);
Jens Axboebcf5a062020-05-22 09:24:42 -06003317 }
Jens Axboebcf5a062020-05-22 09:24:42 -06003318 return 1;
3319}
3320
Jens Axboec1dd91d2020-08-03 16:43:59 -06003321/*
3322 * This controls whether a given IO request should be armed for async page
3323 * based retry. If we return false here, the request is handed to the async
3324 * worker threads for retry. If we're doing buffered reads on a regular file,
3325 * we prepare a private wait_page_queue entry and retry the operation. This
3326 * will either succeed because the page is now uptodate and unlocked, or it
3327 * will register a callback when the page is unlocked at IO completion. Through
3328 * that callback, io_uring uses task_work to setup a retry of the operation.
3329 * That retry will attempt the buffered read again. The retry will generally
3330 * succeed, or in rare cases where it fails, we then fall back to using the
3331 * async worker threads for a blocking retry.
3332 */
Jens Axboe227c0c92020-08-13 11:51:40 -06003333static bool io_rw_should_retry(struct io_kiocb *req)
Jens Axboebcf5a062020-05-22 09:24:42 -06003334{
Jens Axboee8c2bc12020-08-15 18:44:09 -07003335 struct io_async_rw *rw = req->async_data;
3336 struct wait_page_queue *wait = &rw->wpq;
Jens Axboebcf5a062020-05-22 09:24:42 -06003337 struct kiocb *kiocb = &req->rw.kiocb;
Jens Axboebcf5a062020-05-22 09:24:42 -06003338
3339 /* never retry for NOWAIT, we just complete with -EAGAIN */
3340 if (req->flags & REQ_F_NOWAIT)
3341 return false;
3342
Jens Axboe227c0c92020-08-13 11:51:40 -06003343 /* Only for buffered IO */
Jens Axboe3b2a4432020-08-16 10:58:43 -07003344 if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
Jens Axboebcf5a062020-05-22 09:24:42 -06003345 return false;
Jens Axboe3b2a4432020-08-16 10:58:43 -07003346
Jens Axboebcf5a062020-05-22 09:24:42 -06003347 /*
3348 * just use poll if we can, and don't attempt if the fs doesn't
3349 * support callback based unlocks
3350 */
3351 if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
3352 return false;
3353
Jens Axboe3b2a4432020-08-16 10:58:43 -07003354 wait->wait.func = io_async_buf_func;
3355 wait->wait.private = req;
3356 wait->wait.flags = 0;
3357 INIT_LIST_HEAD(&wait->wait.entry);
3358 kiocb->ki_flags |= IOCB_WAITQ;
Hao Xuc8d317a2020-09-29 20:00:45 +08003359 kiocb->ki_flags &= ~IOCB_NOWAIT;
Jens Axboe3b2a4432020-08-16 10:58:43 -07003360 kiocb->ki_waitq = wait;
Jens Axboe3b2a4432020-08-16 10:58:43 -07003361 return true;
Jens Axboebcf5a062020-05-22 09:24:42 -06003362}
3363
3364static int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
3365{
3366 if (req->file->f_op->read_iter)
3367 return call_read_iter(req->file, &req->rw.kiocb, iter);
Guoyu Huang2dd21112020-08-05 03:53:50 -07003368 else if (req->file->f_op->read)
Jens Axboe4017eb92020-10-22 14:14:12 -06003369 return loop_rw_iter(READ, req, iter);
Guoyu Huang2dd21112020-08-05 03:53:50 -07003370 else
3371 return -EINVAL;
Jens Axboebcf5a062020-05-22 09:24:42 -06003372}
3373
Jens Axboea1d7c392020-06-22 11:09:46 -06003374static int io_read(struct io_kiocb *req, bool force_nonblock,
3375 struct io_comp_state *cs)
Jens Axboe2b188cc2019-01-07 10:46:33 -07003376{
3377 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
Jens Axboe9adbd452019-12-20 08:45:55 -07003378 struct kiocb *kiocb = &req->rw.kiocb;
Jens Axboeff6165b2020-08-13 09:47:43 -06003379 struct iov_iter __iter, *iter = &__iter;
Jens Axboee8c2bc12020-08-15 18:44:09 -07003380 struct io_async_rw *rw = req->async_data;
Jens Axboe227c0c92020-08-13 11:51:40 -06003381 ssize_t io_size, ret, ret2;
Jens Axboe31b51512019-01-18 22:56:34 -07003382 size_t iov_count;
Jens Axboef5cac8b2020-09-14 09:30:38 -06003383 bool no_async;
Jens Axboe2b188cc2019-01-07 10:46:33 -07003384
Jens Axboee8c2bc12020-08-15 18:44:09 -07003385 if (rw)
3386 iter = &rw->iter;
Jens Axboeff6165b2020-08-13 09:47:43 -06003387
3388 ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
Jens Axboe06b76d42019-12-19 14:44:26 -07003389 if (ret < 0)
3390 return ret;
Jens Axboeeefdf302020-08-27 16:40:19 -06003391 iov_count = iov_iter_count(iter);
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003392 io_size = ret;
3393 req->result = io_size;
Jens Axboe227c0c92020-08-13 11:51:40 -06003394 ret = 0;
Jens Axboe2b188cc2019-01-07 10:46:33 -07003395
Jens Axboefd6c2e42019-12-18 12:19:41 -07003396 /* Ensure we clear previously set non-block flag */
3397 if (!force_nonblock)
Jens Axboe29de5f62020-02-20 09:56:08 -07003398 kiocb->ki_flags &= ~IOCB_NOWAIT;
Pavel Begunkova88fc402020-09-30 22:57:53 +03003399 else
3400 kiocb->ki_flags |= IOCB_NOWAIT;
3401
Jens Axboefd6c2e42019-12-18 12:19:41 -07003402
Pavel Begunkov24c74672020-06-21 13:09:51 +03003403 /* If the file doesn't support async, just async punt */
Jens Axboef5cac8b2020-09-14 09:30:38 -06003404 no_async = force_nonblock && !io_file_supports_async(req->file, READ);
3405 if (no_async)
Jens Axboef67676d2019-12-02 11:03:47 -07003406 goto copy_iov;
Jens Axboe9e645e112019-05-10 16:07:28 -06003407
Jens Axboe0fef9482020-08-26 10:36:20 -06003408 ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), iov_count);
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003409 if (unlikely(ret))
3410 goto out_free;
Jens Axboe2b188cc2019-01-07 10:46:33 -07003411
Jens Axboe227c0c92020-08-13 11:51:40 -06003412 ret = io_iter_do_read(req, iter);
Jens Axboe32960612019-09-23 11:05:34 -06003413
Jens Axboe227c0c92020-08-13 11:51:40 -06003414 if (!ret) {
3415 goto done;
3416 } else if (ret == -EIOCBQUEUED) {
3417 ret = 0;
3418 goto out_free;
3419 } else if (ret == -EAGAIN) {
Jens Axboeeefdf302020-08-27 16:40:19 -06003420 /* IOPOLL retry should happen for io-wq threads */
3421 if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
Jens Axboef91daf52020-08-15 15:58:42 -07003422 goto done;
Jens Axboe355afae2020-09-02 09:30:31 -06003423 /* no retry on NONBLOCK marked file */
3424 if (req->file->f_flags & O_NONBLOCK)
3425 goto done;
Jens Axboe84216312020-08-24 11:45:26 -06003426 /* some cases will consume bytes even on error returns */
3427 iov_iter_revert(iter, iov_count - iov_iter_count(iter));
Jens Axboef38c7e32020-09-25 15:23:43 -06003428 ret = 0;
3429 goto copy_iov;
Jens Axboe227c0c92020-08-13 11:51:40 -06003430 } else if (ret < 0) {
Jens Axboe00d23d52020-08-25 12:59:22 -06003431 /* make sure -ERESTARTSYS -> -EINTR is done */
3432 goto done;
Jens Axboe227c0c92020-08-13 11:51:40 -06003433 }
3434
3435 /* read it all, or we did blocking attempt. no retry. */
Jens Axboef91daf52020-08-15 15:58:42 -07003436 if (!iov_iter_count(iter) || !force_nonblock ||
3437 (req->file->f_flags & O_NONBLOCK))
Jens Axboe227c0c92020-08-13 11:51:40 -06003438 goto done;
3439
3440 io_size -= ret;
3441copy_iov:
3442 ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
3443 if (ret2) {
3444 ret = ret2;
3445 goto out_free;
3446 }
Jens Axboef5cac8b2020-09-14 09:30:38 -06003447 if (no_async)
3448 return -EAGAIN;
Jens Axboee8c2bc12020-08-15 18:44:09 -07003449 rw = req->async_data;
Jens Axboe227c0c92020-08-13 11:51:40 -06003450 /* it's copied and will be cleaned with ->io */
3451 iovec = NULL;
3452 /* now use our persistent iterator, if we aren't already */
Jens Axboee8c2bc12020-08-15 18:44:09 -07003453 iter = &rw->iter;
Jens Axboe227c0c92020-08-13 11:51:40 -06003454retry:
Jens Axboee8c2bc12020-08-15 18:44:09 -07003455 rw->bytes_done += ret;
Jens Axboe227c0c92020-08-13 11:51:40 -06003456 /* if we can retry, do so with the callbacks armed */
3457 if (!io_rw_should_retry(req)) {
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003458 kiocb->ki_flags &= ~IOCB_WAITQ;
3459 return -EAGAIN;
Jens Axboe2b188cc2019-01-07 10:46:33 -07003460 }
Jens Axboe227c0c92020-08-13 11:51:40 -06003461
3462 /*
3463 * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
3464 * get -EIOCBQUEUED, then we'll get a notification when the desired
3465 * page gets unlocked. We can also get a partial read here, and if we
3466 * do, then just retry at the new offset.
3467 */
3468 ret = io_iter_do_read(req, iter);
3469 if (ret == -EIOCBQUEUED) {
3470 ret = 0;
3471 goto out_free;
3472 } else if (ret > 0 && ret < io_size) {
3473 /* we got some bytes, but not all. retry. */
3474 goto retry;
3475 }
3476done:
3477 kiocb_done(kiocb, ret, cs);
3478 ret = 0;
Jens Axboef67676d2019-12-02 11:03:47 -07003479out_free:
Pavel Begunkovf261c162020-08-20 11:34:10 +03003480 /* it's reportedly faster than delegating the null check to kfree() */
Pavel Begunkov252917c2020-07-13 22:59:20 +03003481 if (iovec)
Xiaoguang Wang6f2cc162020-06-18 15:01:56 +08003482 kfree(iovec);
Jens Axboe2b188cc2019-01-07 10:46:33 -07003483 return ret;
3484}
3485
Pavel Begunkov73debe62020-09-30 22:57:54 +03003486static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboef67676d2019-12-02 11:03:47 -07003487{
3488 ssize_t ret;
3489
Pavel Begunkova88fc402020-09-30 22:57:53 +03003490 ret = io_prep_rw(req, sqe);
Jens Axboe3529d8c2019-12-19 18:24:38 -07003491 if (ret)
3492 return ret;
Jens Axboef67676d2019-12-02 11:03:47 -07003493
Jens Axboe3529d8c2019-12-19 18:24:38 -07003494 if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
3495 return -EBADF;
Jens Axboef67676d2019-12-02 11:03:47 -07003496
Pavel Begunkov5f798be2020-02-08 13:28:02 +03003497 /* either don't need iovec imported or already have it */
Pavel Begunkov2d199892020-09-30 22:57:35 +03003498 if (!req->async_data)
Jens Axboe3529d8c2019-12-19 18:24:38 -07003499 return 0;
Pavel Begunkov73debe62020-09-30 22:57:54 +03003500 return io_rw_prep_async(req, WRITE);
Jens Axboef67676d2019-12-02 11:03:47 -07003501}
3502
Jens Axboea1d7c392020-06-22 11:09:46 -06003503static int io_write(struct io_kiocb *req, bool force_nonblock,
3504 struct io_comp_state *cs)
Jens Axboe2b188cc2019-01-07 10:46:33 -07003505{
3506 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
Jens Axboe9adbd452019-12-20 08:45:55 -07003507 struct kiocb *kiocb = &req->rw.kiocb;
Jens Axboeff6165b2020-08-13 09:47:43 -06003508 struct iov_iter __iter, *iter = &__iter;
Jens Axboee8c2bc12020-08-15 18:44:09 -07003509 struct io_async_rw *rw = req->async_data;
Jens Axboe31b51512019-01-18 22:56:34 -07003510 size_t iov_count;
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003511 ssize_t ret, ret2, io_size;
Jens Axboe2b188cc2019-01-07 10:46:33 -07003512
Jens Axboee8c2bc12020-08-15 18:44:09 -07003513 if (rw)
3514 iter = &rw->iter;
Jens Axboeff6165b2020-08-13 09:47:43 -06003515
3516 ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
Jens Axboe06b76d42019-12-19 14:44:26 -07003517 if (ret < 0)
3518 return ret;
Jens Axboeeefdf302020-08-27 16:40:19 -06003519 iov_count = iov_iter_count(iter);
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003520 io_size = ret;
3521 req->result = io_size;
Jens Axboe2b188cc2019-01-07 10:46:33 -07003522
Jens Axboefd6c2e42019-12-18 12:19:41 -07003523 /* Ensure we clear previously set non-block flag */
3524 if (!force_nonblock)
Pavel Begunkova88fc402020-09-30 22:57:53 +03003525 kiocb->ki_flags &= ~IOCB_NOWAIT;
3526 else
3527 kiocb->ki_flags |= IOCB_NOWAIT;
Jens Axboefd6c2e42019-12-18 12:19:41 -07003528
Pavel Begunkov24c74672020-06-21 13:09:51 +03003529 /* If the file doesn't support async, just async punt */
Jens Axboeaf197f52020-04-28 13:15:06 -06003530 if (force_nonblock && !io_file_supports_async(req->file, WRITE))
Jens Axboef67676d2019-12-02 11:03:47 -07003531 goto copy_iov;
Jens Axboef67676d2019-12-02 11:03:47 -07003532
Jens Axboe10d59342019-12-09 20:16:22 -07003533 /* file path doesn't support NOWAIT for non-direct_IO */
3534 if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
3535 (req->flags & REQ_F_ISREG))
Jens Axboef67676d2019-12-02 11:03:47 -07003536 goto copy_iov;
Jens Axboe9e645e112019-05-10 16:07:28 -06003537
Jens Axboe0fef9482020-08-26 10:36:20 -06003538 ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), iov_count);
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003539 if (unlikely(ret))
3540 goto out_free;
Roman Penyaev9bf79332019-03-25 20:09:24 +01003541
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003542 /*
3543 * Open-code file_start_write here to grab freeze protection,
3544 * which will be released by another thread in
3545 * io_complete_rw(). Fool lockdep by telling it the lock got
3546 * released so that it doesn't complain about the held lock when
3547 * we return to userspace.
3548 */
3549 if (req->flags & REQ_F_ISREG) {
3550 __sb_start_write(file_inode(req->file)->i_sb,
3551 SB_FREEZE_WRITE, true);
3552 __sb_writers_release(file_inode(req->file)->i_sb,
3553 SB_FREEZE_WRITE);
3554 }
3555 kiocb->ki_flags |= IOCB_WRITE;
Roman Penyaev9bf79332019-03-25 20:09:24 +01003556
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003557 if (req->file->f_op->write_iter)
Jens Axboeff6165b2020-08-13 09:47:43 -06003558 ret2 = call_write_iter(req->file, kiocb, iter);
Guoyu Huang2dd21112020-08-05 03:53:50 -07003559 else if (req->file->f_op->write)
Jens Axboe4017eb92020-10-22 14:14:12 -06003560 ret2 = loop_rw_iter(WRITE, req, iter);
Guoyu Huang2dd21112020-08-05 03:53:50 -07003561 else
3562 ret2 = -EINVAL;
Jens Axboe4ed734b2020-03-20 11:23:41 -06003563
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003564 /*
3565 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3566 * retry them without IOCB_NOWAIT.
3567 */
3568 if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
3569 ret2 = -EAGAIN;
Jens Axboe355afae2020-09-02 09:30:31 -06003570 /* no retry on NONBLOCK marked file */
3571 if (ret2 == -EAGAIN && (req->file->f_flags & O_NONBLOCK))
3572 goto done;
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003573 if (!force_nonblock || ret2 != -EAGAIN) {
Jens Axboeeefdf302020-08-27 16:40:19 -06003574 /* IOPOLL retry should happen for io-wq threads */
3575 if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
3576 goto copy_iov;
Jens Axboe355afae2020-09-02 09:30:31 -06003577done:
Pavel Begunkovfa15baf2020-08-01 13:50:02 +03003578 kiocb_done(kiocb, ret2, cs);
3579 } else {
Jens Axboef67676d2019-12-02 11:03:47 -07003580copy_iov:
Jens Axboe84216312020-08-24 11:45:26 -06003581 /* some cases will consume bytes even on error returns */
3582 iov_iter_revert(iter, iov_count - iov_iter_count(iter));
Jens Axboe227c0c92020-08-13 11:51:40 -06003583 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
Jens Axboeff6165b2020-08-13 09:47:43 -06003584 if (!ret)
3585 return -EAGAIN;
Jens Axboe2b188cc2019-01-07 10:46:33 -07003586 }
Jens Axboe31b51512019-01-18 22:56:34 -07003587out_free:
Pavel Begunkovf261c162020-08-20 11:34:10 +03003588 /* it's reportedly faster than delegating the null check to kfree() */
Pavel Begunkov252917c2020-07-13 22:59:20 +03003589 if (iovec)
Xiaoguang Wang6f2cc162020-06-18 15:01:56 +08003590 kfree(iovec);
Jens Axboe2b188cc2019-01-07 10:46:33 -07003591 return ret;
3592}
3593
Pavel Begunkovf2a8d5c2020-05-17 14:18:06 +03003594static int __io_splice_prep(struct io_kiocb *req,
3595 const struct io_uring_sqe *sqe)
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003596{
3597 struct io_splice* sp = &req->splice;
3598 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003599
Pavel Begunkov3232dd02020-06-03 18:03:22 +03003600 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3601 return -EINVAL;
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003602
3603 sp->file_in = NULL;
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003604 sp->len = READ_ONCE(sqe->len);
3605 sp->flags = READ_ONCE(sqe->splice_flags);
3606
3607 if (unlikely(sp->flags & ~valid_flags))
3608 return -EINVAL;
3609
Pavel Begunkov8371adf2020-10-10 18:34:08 +01003610 sp->file_in = io_file_get(NULL, req, READ_ONCE(sqe->splice_fd_in),
3611 (sp->flags & SPLICE_F_FD_IN_FIXED));
3612 if (!sp->file_in)
3613 return -EBADF;
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003614 req->flags |= REQ_F_NEED_CLEANUP;
3615
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08003616 if (!S_ISREG(file_inode(sp->file_in)->i_mode)) {
3617 /*
3618 * Splice operation will be punted aync, and here need to
3619 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3620 */
3621 io_req_init_async(req);
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003622 req->work.flags |= IO_WQ_WORK_UNBOUND;
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08003623 }
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003624
3625 return 0;
3626}
3627
Pavel Begunkovf2a8d5c2020-05-17 14:18:06 +03003628static int io_tee_prep(struct io_kiocb *req,
3629 const struct io_uring_sqe *sqe)
3630{
3631 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
3632 return -EINVAL;
3633 return __io_splice_prep(req, sqe);
3634}
3635
3636static int io_tee(struct io_kiocb *req, bool force_nonblock)
3637{
3638 struct io_splice *sp = &req->splice;
3639 struct file *in = sp->file_in;
3640 struct file *out = sp->file_out;
3641 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3642 long ret = 0;
3643
3644 if (force_nonblock)
3645 return -EAGAIN;
3646 if (sp->len)
3647 ret = do_tee(in, out, sp->len, flags);
3648
3649 io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED));
3650 req->flags &= ~REQ_F_NEED_CLEANUP;
3651
Pavel Begunkovf2a8d5c2020-05-17 14:18:06 +03003652 if (ret != sp->len)
3653 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06003654 io_req_complete(req, ret);
Pavel Begunkovf2a8d5c2020-05-17 14:18:06 +03003655 return 0;
3656}
3657
3658static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3659{
3660 struct io_splice* sp = &req->splice;
3661
3662 sp->off_in = READ_ONCE(sqe->splice_off_in);
3663 sp->off_out = READ_ONCE(sqe->off);
3664 return __io_splice_prep(req, sqe);
3665}
3666
Pavel Begunkov014db002020-03-03 21:33:12 +03003667static int io_splice(struct io_kiocb *req, bool force_nonblock)
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003668{
3669 struct io_splice *sp = &req->splice;
3670 struct file *in = sp->file_in;
3671 struct file *out = sp->file_out;
3672 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3673 loff_t *poff_in, *poff_out;
Pavel Begunkovc9687422020-05-04 23:00:54 +03003674 long ret = 0;
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003675
Pavel Begunkov2fb3e822020-05-01 17:09:38 +03003676 if (force_nonblock)
3677 return -EAGAIN;
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003678
3679 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
3680 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
Pavel Begunkovc9687422020-05-04 23:00:54 +03003681
Jens Axboe948a7742020-05-17 14:21:38 -06003682 if (sp->len)
Pavel Begunkovc9687422020-05-04 23:00:54 +03003683 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003684
3685 io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED));
3686 req->flags &= ~REQ_F_NEED_CLEANUP;
3687
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003688 if (ret != sp->len)
3689 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06003690 io_req_complete(req, ret);
Pavel Begunkov7d67af22020-02-24 11:32:45 +03003691 return 0;
3692}
3693
Jens Axboe2b188cc2019-01-07 10:46:33 -07003694/*
3695 * IORING_OP_NOP just posts a completion event, nothing else.
3696 */
Jens Axboe229a7b62020-06-22 10:13:11 -06003697static int io_nop(struct io_kiocb *req, struct io_comp_state *cs)
Jens Axboe2b188cc2019-01-07 10:46:33 -07003698{
3699 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe2b188cc2019-01-07 10:46:33 -07003700
Jens Axboedef596e2019-01-09 08:59:42 -07003701 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
3702 return -EINVAL;
3703
Jens Axboe229a7b62020-06-22 10:13:11 -06003704 __io_req_complete(req, 0, 0, cs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07003705 return 0;
3706}
3707
Jens Axboe3529d8c2019-12-19 18:24:38 -07003708static int io_prep_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Christoph Hellwigc992fe22019-01-11 09:43:02 -07003709{
Jens Axboe6b063142019-01-10 22:13:58 -07003710 struct io_ring_ctx *ctx = req->ctx;
Christoph Hellwigc992fe22019-01-11 09:43:02 -07003711
Jens Axboe09bb8392019-03-13 12:39:28 -06003712 if (!req->file)
3713 return -EBADF;
Christoph Hellwigc992fe22019-01-11 09:43:02 -07003714
Jens Axboe6b063142019-01-10 22:13:58 -07003715 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
Jens Axboedef596e2019-01-09 08:59:42 -07003716 return -EINVAL;
Jens Axboeedafcce2019-01-09 09:16:05 -07003717 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
Christoph Hellwigc992fe22019-01-11 09:43:02 -07003718 return -EINVAL;
3719
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07003720 req->sync.flags = READ_ONCE(sqe->fsync_flags);
3721 if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
3722 return -EINVAL;
3723
3724 req->sync.off = READ_ONCE(sqe->off);
3725 req->sync.len = READ_ONCE(sqe->len);
Christoph Hellwigc992fe22019-01-11 09:43:02 -07003726 return 0;
3727}
3728
Pavel Begunkovac45abc2020-06-08 21:08:18 +03003729static int io_fsync(struct io_kiocb *req, bool force_nonblock)
Jens Axboe78912932020-01-14 22:09:06 -07003730{
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07003731 loff_t end = req->sync.off + req->sync.len;
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07003732 int ret;
3733
Pavel Begunkovac45abc2020-06-08 21:08:18 +03003734 /* fsync always requires a blocking context */
3735 if (force_nonblock)
3736 return -EAGAIN;
3737
Jens Axboe9adbd452019-12-20 08:45:55 -07003738 ret = vfs_fsync_range(req->file, req->sync.off,
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07003739 end > 0 ? end : LLONG_MAX,
3740 req->sync.flags & IORING_FSYNC_DATASYNC);
3741 if (ret < 0)
3742 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06003743 io_req_complete(req, ret);
Christoph Hellwigc992fe22019-01-11 09:43:02 -07003744 return 0;
3745}
3746
Jens Axboed63d1b52019-12-10 10:38:56 -07003747static int io_fallocate_prep(struct io_kiocb *req,
3748 const struct io_uring_sqe *sqe)
3749{
3750 if (sqe->ioprio || sqe->buf_index || sqe->rw_flags)
3751 return -EINVAL;
Pavel Begunkov3232dd02020-06-03 18:03:22 +03003752 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3753 return -EINVAL;
Jens Axboed63d1b52019-12-10 10:38:56 -07003754
3755 req->sync.off = READ_ONCE(sqe->off);
3756 req->sync.len = READ_ONCE(sqe->addr);
3757 req->sync.mode = READ_ONCE(sqe->len);
3758 return 0;
3759}
3760
Pavel Begunkov014db002020-03-03 21:33:12 +03003761static int io_fallocate(struct io_kiocb *req, bool force_nonblock)
Jens Axboed63d1b52019-12-10 10:38:56 -07003762{
Pavel Begunkovac45abc2020-06-08 21:08:18 +03003763 int ret;
Jens Axboed63d1b52019-12-10 10:38:56 -07003764
Pavel Begunkovac45abc2020-06-08 21:08:18 +03003765 /* fallocate always requiring blocking context */
3766 if (force_nonblock)
3767 return -EAGAIN;
Pavel Begunkovac45abc2020-06-08 21:08:18 +03003768 ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
3769 req->sync.len);
Pavel Begunkovac45abc2020-06-08 21:08:18 +03003770 if (ret < 0)
3771 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06003772 io_req_complete(req, ret);
Jens Axboed63d1b52019-12-10 10:38:56 -07003773 return 0;
3774}
3775
Pavel Begunkovec65fea2020-06-03 18:03:24 +03003776static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboe15b71ab2019-12-11 11:20:36 -07003777{
Jens Axboef8748882020-01-08 17:47:02 -07003778 const char __user *fname;
Jens Axboe15b71ab2019-12-11 11:20:36 -07003779 int ret;
3780
Pavel Begunkovec65fea2020-06-03 18:03:24 +03003781 if (unlikely(sqe->ioprio || sqe->buf_index))
Jens Axboe15b71ab2019-12-11 11:20:36 -07003782 return -EINVAL;
Pavel Begunkovec65fea2020-06-03 18:03:24 +03003783 if (unlikely(req->flags & REQ_F_FIXED_FILE))
Jens Axboecf3040c2020-02-06 21:31:40 -07003784 return -EBADF;
Jens Axboe15b71ab2019-12-11 11:20:36 -07003785
Pavel Begunkovec65fea2020-06-03 18:03:24 +03003786 /* open.how should be already initialised */
3787 if (!(req->open.how.flags & O_PATH) && force_o_largefile())
Jens Axboe08a1d26eb2020-04-08 09:20:54 -06003788 req->open.how.flags |= O_LARGEFILE;
Jens Axboe15b71ab2019-12-11 11:20:36 -07003789
Pavel Begunkov25e72d12020-06-03 18:03:23 +03003790 req->open.dfd = READ_ONCE(sqe->fd);
3791 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
Jens Axboef8748882020-01-08 17:47:02 -07003792 req->open.filename = getname(fname);
Jens Axboe15b71ab2019-12-11 11:20:36 -07003793 if (IS_ERR(req->open.filename)) {
3794 ret = PTR_ERR(req->open.filename);
3795 req->open.filename = NULL;
3796 return ret;
3797 }
Jens Axboe4022e7a2020-03-19 19:23:18 -06003798 req->open.nofile = rlimit(RLIMIT_NOFILE);
Pavel Begunkov8fef80b2020-02-07 23:59:53 +03003799 req->flags |= REQ_F_NEED_CLEANUP;
Jens Axboe15b71ab2019-12-11 11:20:36 -07003800 return 0;
3801}
3802
Pavel Begunkovec65fea2020-06-03 18:03:24 +03003803static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3804{
3805 u64 flags, mode;
3806
Jens Axboe4eb8dde2020-09-18 19:36:24 -06003807 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
3808 return -EINVAL;
Pavel Begunkovec65fea2020-06-03 18:03:24 +03003809 mode = READ_ONCE(sqe->len);
3810 flags = READ_ONCE(sqe->open_flags);
3811 req->open.how = build_open_how(flags, mode);
3812 return __io_openat_prep(req, sqe);
3813}
3814
Jens Axboecebdb982020-01-08 17:59:24 -07003815static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3816{
3817 struct open_how __user *how;
Jens Axboecebdb982020-01-08 17:59:24 -07003818 size_t len;
3819 int ret;
3820
Jens Axboe4eb8dde2020-09-18 19:36:24 -06003821 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
3822 return -EINVAL;
Jens Axboecebdb982020-01-08 17:59:24 -07003823 how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3824 len = READ_ONCE(sqe->len);
Jens Axboecebdb982020-01-08 17:59:24 -07003825 if (len < OPEN_HOW_SIZE_VER0)
3826 return -EINVAL;
3827
3828 ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
3829 len);
3830 if (ret)
3831 return ret;
3832
Pavel Begunkovec65fea2020-06-03 18:03:24 +03003833 return __io_openat_prep(req, sqe);
Jens Axboecebdb982020-01-08 17:59:24 -07003834}
3835
Pavel Begunkov014db002020-03-03 21:33:12 +03003836static int io_openat2(struct io_kiocb *req, bool force_nonblock)
Jens Axboe15b71ab2019-12-11 11:20:36 -07003837{
3838 struct open_flags op;
Jens Axboe15b71ab2019-12-11 11:20:36 -07003839 struct file *file;
3840 int ret;
3841
Jens Axboef86cd202020-01-29 13:46:44 -07003842 if (force_nonblock)
Jens Axboe15b71ab2019-12-11 11:20:36 -07003843 return -EAGAIN;
Jens Axboe15b71ab2019-12-11 11:20:36 -07003844
Jens Axboecebdb982020-01-08 17:59:24 -07003845 ret = build_open_flags(&req->open.how, &op);
Jens Axboe15b71ab2019-12-11 11:20:36 -07003846 if (ret)
3847 goto err;
3848
Jens Axboe4022e7a2020-03-19 19:23:18 -06003849 ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
Jens Axboe15b71ab2019-12-11 11:20:36 -07003850 if (ret < 0)
3851 goto err;
3852
3853 file = do_filp_open(req->open.dfd, req->open.filename, &op);
3854 if (IS_ERR(file)) {
3855 put_unused_fd(ret);
3856 ret = PTR_ERR(file);
3857 } else {
3858 fsnotify_open(file);
3859 fd_install(ret, file);
3860 }
3861err:
3862 putname(req->open.filename);
Pavel Begunkov8fef80b2020-02-07 23:59:53 +03003863 req->flags &= ~REQ_F_NEED_CLEANUP;
Jens Axboe15b71ab2019-12-11 11:20:36 -07003864 if (ret < 0)
3865 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06003866 io_req_complete(req, ret);
Jens Axboe15b71ab2019-12-11 11:20:36 -07003867 return 0;
3868}
3869
Pavel Begunkov014db002020-03-03 21:33:12 +03003870static int io_openat(struct io_kiocb *req, bool force_nonblock)
Jens Axboecebdb982020-01-08 17:59:24 -07003871{
Pavel Begunkov014db002020-03-03 21:33:12 +03003872 return io_openat2(req, force_nonblock);
Jens Axboecebdb982020-01-08 17:59:24 -07003873}
3874
Jens Axboe067524e2020-03-02 16:32:28 -07003875static int io_remove_buffers_prep(struct io_kiocb *req,
3876 const struct io_uring_sqe *sqe)
3877{
3878 struct io_provide_buf *p = &req->pbuf;
3879 u64 tmp;
3880
3881 if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off)
3882 return -EINVAL;
3883
3884 tmp = READ_ONCE(sqe->fd);
3885 if (!tmp || tmp > USHRT_MAX)
3886 return -EINVAL;
3887
3888 memset(p, 0, sizeof(*p));
3889 p->nbufs = tmp;
3890 p->bgid = READ_ONCE(sqe->buf_group);
3891 return 0;
3892}
3893
3894static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
3895 int bgid, unsigned nbufs)
3896{
3897 unsigned i = 0;
3898
3899 /* shouldn't happen */
3900 if (!nbufs)
3901 return 0;
3902
3903 /* the head kbuf is the list itself */
3904 while (!list_empty(&buf->list)) {
3905 struct io_buffer *nxt;
3906
3907 nxt = list_first_entry(&buf->list, struct io_buffer, list);
3908 list_del(&nxt->list);
3909 kfree(nxt);
3910 if (++i == nbufs)
3911 return i;
3912 }
3913 i++;
3914 kfree(buf);
3915 idr_remove(&ctx->io_buffer_idr, bgid);
3916
3917 return i;
3918}
3919
Jens Axboe229a7b62020-06-22 10:13:11 -06003920static int io_remove_buffers(struct io_kiocb *req, bool force_nonblock,
3921 struct io_comp_state *cs)
Jens Axboe067524e2020-03-02 16:32:28 -07003922{
3923 struct io_provide_buf *p = &req->pbuf;
3924 struct io_ring_ctx *ctx = req->ctx;
3925 struct io_buffer *head;
3926 int ret = 0;
3927
3928 io_ring_submit_lock(ctx, !force_nonblock);
3929
3930 lockdep_assert_held(&ctx->uring_lock);
3931
3932 ret = -ENOENT;
3933 head = idr_find(&ctx->io_buffer_idr, p->bgid);
3934 if (head)
3935 ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
3936
3937 io_ring_submit_lock(ctx, !force_nonblock);
3938 if (ret < 0)
3939 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06003940 __io_req_complete(req, ret, 0, cs);
Jens Axboe067524e2020-03-02 16:32:28 -07003941 return 0;
3942}
3943
Jens Axboeddf0322d2020-02-23 16:41:33 -07003944static int io_provide_buffers_prep(struct io_kiocb *req,
3945 const struct io_uring_sqe *sqe)
3946{
3947 struct io_provide_buf *p = &req->pbuf;
3948 u64 tmp;
3949
3950 if (sqe->ioprio || sqe->rw_flags)
3951 return -EINVAL;
3952
3953 tmp = READ_ONCE(sqe->fd);
3954 if (!tmp || tmp > USHRT_MAX)
3955 return -E2BIG;
3956 p->nbufs = tmp;
3957 p->addr = READ_ONCE(sqe->addr);
3958 p->len = READ_ONCE(sqe->len);
3959
Bijan Mottahedehefe68c12020-06-04 18:01:52 -07003960 if (!access_ok(u64_to_user_ptr(p->addr), (p->len * p->nbufs)))
Jens Axboeddf0322d2020-02-23 16:41:33 -07003961 return -EFAULT;
3962
3963 p->bgid = READ_ONCE(sqe->buf_group);
3964 tmp = READ_ONCE(sqe->off);
3965 if (tmp > USHRT_MAX)
3966 return -E2BIG;
3967 p->bid = tmp;
3968 return 0;
3969}
3970
3971static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
3972{
3973 struct io_buffer *buf;
3974 u64 addr = pbuf->addr;
3975 int i, bid = pbuf->bid;
3976
3977 for (i = 0; i < pbuf->nbufs; i++) {
3978 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
3979 if (!buf)
3980 break;
3981
3982 buf->addr = addr;
3983 buf->len = pbuf->len;
3984 buf->bid = bid;
3985 addr += pbuf->len;
3986 bid++;
3987 if (!*head) {
3988 INIT_LIST_HEAD(&buf->list);
3989 *head = buf;
3990 } else {
3991 list_add_tail(&buf->list, &(*head)->list);
3992 }
3993 }
3994
3995 return i ? i : -ENOMEM;
3996}
3997
Jens Axboe229a7b62020-06-22 10:13:11 -06003998static int io_provide_buffers(struct io_kiocb *req, bool force_nonblock,
3999 struct io_comp_state *cs)
Jens Axboeddf0322d2020-02-23 16:41:33 -07004000{
4001 struct io_provide_buf *p = &req->pbuf;
4002 struct io_ring_ctx *ctx = req->ctx;
4003 struct io_buffer *head, *list;
4004 int ret = 0;
4005
4006 io_ring_submit_lock(ctx, !force_nonblock);
4007
4008 lockdep_assert_held(&ctx->uring_lock);
4009
4010 list = head = idr_find(&ctx->io_buffer_idr, p->bgid);
4011
4012 ret = io_add_buffers(p, &head);
4013 if (ret < 0)
4014 goto out;
4015
4016 if (!list) {
4017 ret = idr_alloc(&ctx->io_buffer_idr, head, p->bgid, p->bgid + 1,
4018 GFP_KERNEL);
4019 if (ret < 0) {
Jens Axboe067524e2020-03-02 16:32:28 -07004020 __io_remove_buffers(ctx, head, p->bgid, -1U);
Jens Axboeddf0322d2020-02-23 16:41:33 -07004021 goto out;
4022 }
4023 }
4024out:
4025 io_ring_submit_unlock(ctx, !force_nonblock);
4026 if (ret < 0)
4027 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06004028 __io_req_complete(req, ret, 0, cs);
Jens Axboeddf0322d2020-02-23 16:41:33 -07004029 return 0;
Jens Axboe2b188cc2019-01-07 10:46:33 -07004030}
4031
Jens Axboe3e4827b2020-01-08 15:18:09 -07004032static int io_epoll_ctl_prep(struct io_kiocb *req,
4033 const struct io_uring_sqe *sqe)
4034{
4035#if defined(CONFIG_EPOLL)
4036 if (sqe->ioprio || sqe->buf_index)
4037 return -EINVAL;
Jens Axboe6ca56f82020-09-18 16:51:19 -06004038 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL)))
Pavel Begunkov3232dd02020-06-03 18:03:22 +03004039 return -EINVAL;
Jens Axboe3e4827b2020-01-08 15:18:09 -07004040
4041 req->epoll.epfd = READ_ONCE(sqe->fd);
4042 req->epoll.op = READ_ONCE(sqe->len);
4043 req->epoll.fd = READ_ONCE(sqe->off);
4044
4045 if (ep_op_has_event(req->epoll.op)) {
4046 struct epoll_event __user *ev;
4047
4048 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
4049 if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
4050 return -EFAULT;
4051 }
4052
4053 return 0;
4054#else
4055 return -EOPNOTSUPP;
4056#endif
4057}
4058
Jens Axboe229a7b62020-06-22 10:13:11 -06004059static int io_epoll_ctl(struct io_kiocb *req, bool force_nonblock,
4060 struct io_comp_state *cs)
Jens Axboe3e4827b2020-01-08 15:18:09 -07004061{
4062#if defined(CONFIG_EPOLL)
4063 struct io_epoll *ie = &req->epoll;
4064 int ret;
4065
4066 ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
4067 if (force_nonblock && ret == -EAGAIN)
4068 return -EAGAIN;
4069
4070 if (ret < 0)
4071 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06004072 __io_req_complete(req, ret, 0, cs);
Jens Axboe3e4827b2020-01-08 15:18:09 -07004073 return 0;
4074#else
4075 return -EOPNOTSUPP;
4076#endif
4077}
4078
Jens Axboec1ca7572019-12-25 22:18:28 -07004079static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4080{
4081#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4082 if (sqe->ioprio || sqe->buf_index || sqe->off)
4083 return -EINVAL;
Pavel Begunkov3232dd02020-06-03 18:03:22 +03004084 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4085 return -EINVAL;
Jens Axboec1ca7572019-12-25 22:18:28 -07004086
4087 req->madvise.addr = READ_ONCE(sqe->addr);
4088 req->madvise.len = READ_ONCE(sqe->len);
4089 req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
4090 return 0;
4091#else
4092 return -EOPNOTSUPP;
4093#endif
4094}
4095
Pavel Begunkov014db002020-03-03 21:33:12 +03004096static int io_madvise(struct io_kiocb *req, bool force_nonblock)
Jens Axboec1ca7572019-12-25 22:18:28 -07004097{
4098#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4099 struct io_madvise *ma = &req->madvise;
4100 int ret;
4101
4102 if (force_nonblock)
4103 return -EAGAIN;
4104
Minchan Kim0726b012020-10-17 16:14:50 -07004105 ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
Jens Axboec1ca7572019-12-25 22:18:28 -07004106 if (ret < 0)
4107 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06004108 io_req_complete(req, ret);
Jens Axboec1ca7572019-12-25 22:18:28 -07004109 return 0;
4110#else
4111 return -EOPNOTSUPP;
4112#endif
4113}
4114
Jens Axboe4840e412019-12-25 22:03:45 -07004115static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4116{
4117 if (sqe->ioprio || sqe->buf_index || sqe->addr)
4118 return -EINVAL;
Pavel Begunkov3232dd02020-06-03 18:03:22 +03004119 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4120 return -EINVAL;
Jens Axboe4840e412019-12-25 22:03:45 -07004121
4122 req->fadvise.offset = READ_ONCE(sqe->off);
4123 req->fadvise.len = READ_ONCE(sqe->len);
4124 req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
4125 return 0;
4126}
4127
Pavel Begunkov014db002020-03-03 21:33:12 +03004128static int io_fadvise(struct io_kiocb *req, bool force_nonblock)
Jens Axboe4840e412019-12-25 22:03:45 -07004129{
4130 struct io_fadvise *fa = &req->fadvise;
4131 int ret;
4132
Jens Axboe3e694262020-02-01 09:22:49 -07004133 if (force_nonblock) {
4134 switch (fa->advice) {
4135 case POSIX_FADV_NORMAL:
4136 case POSIX_FADV_RANDOM:
4137 case POSIX_FADV_SEQUENTIAL:
4138 break;
4139 default:
4140 return -EAGAIN;
4141 }
4142 }
Jens Axboe4840e412019-12-25 22:03:45 -07004143
4144 ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
4145 if (ret < 0)
4146 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06004147 io_req_complete(req, ret);
Jens Axboe4840e412019-12-25 22:03:45 -07004148 return 0;
4149}
4150
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004151static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4152{
Jens Axboe6ca56f82020-09-18 16:51:19 -06004153 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL)))
Pavel Begunkov3232dd02020-06-03 18:03:22 +03004154 return -EINVAL;
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004155 if (sqe->ioprio || sqe->buf_index)
4156 return -EINVAL;
Pavel Begunkov9c280f92020-04-08 08:58:46 +03004157 if (req->flags & REQ_F_FIXED_FILE)
Jens Axboecf3040c2020-02-06 21:31:40 -07004158 return -EBADF;
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004159
Bijan Mottahedeh1d9e1282020-05-22 21:31:16 -07004160 req->statx.dfd = READ_ONCE(sqe->fd);
4161 req->statx.mask = READ_ONCE(sqe->len);
Bijan Mottahedehe62753e2020-05-22 21:31:18 -07004162 req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
Bijan Mottahedeh1d9e1282020-05-22 21:31:16 -07004163 req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4164 req->statx.flags = READ_ONCE(sqe->statx_flags);
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004165
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004166 return 0;
4167}
4168
Pavel Begunkov014db002020-03-03 21:33:12 +03004169static int io_statx(struct io_kiocb *req, bool force_nonblock)
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004170{
Bijan Mottahedeh1d9e1282020-05-22 21:31:16 -07004171 struct io_statx *ctx = &req->statx;
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004172 int ret;
4173
Jens Axboe5b0bbee2020-04-27 10:41:22 -06004174 if (force_nonblock) {
4175 /* only need file table for an actual valid fd */
4176 if (ctx->dfd == -1 || ctx->dfd == AT_FDCWD)
4177 req->flags |= REQ_F_NO_FILE_TABLE;
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004178 return -EAGAIN;
Jens Axboe5b0bbee2020-04-27 10:41:22 -06004179 }
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004180
Bijan Mottahedehe62753e2020-05-22 21:31:18 -07004181 ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
4182 ctx->buffer);
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004183
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004184 if (ret < 0)
4185 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06004186 io_req_complete(req, ret);
Jens Axboeeddc7ef2019-12-13 21:18:10 -07004187 return 0;
4188}
4189
Jens Axboeb5dba592019-12-11 14:02:38 -07004190static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4191{
4192 /*
4193 * If we queue this for async, it must not be cancellable. That would
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08004194 * leave the 'file' in an undeterminate state, and here need to modify
4195 * io_wq_work.flags, so initialize io_wq_work firstly.
Jens Axboeb5dba592019-12-11 14:02:38 -07004196 */
Xiaoguang Wang7cdaf582020-06-10 19:41:19 +08004197 io_req_init_async(req);
Jens Axboeb5dba592019-12-11 14:02:38 -07004198 req->work.flags |= IO_WQ_WORK_NO_CANCEL;
4199
Pavel Begunkov3232dd02020-06-03 18:03:22 +03004200 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
4201 return -EINVAL;
Jens Axboeb5dba592019-12-11 14:02:38 -07004202 if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
4203 sqe->rw_flags || sqe->buf_index)
4204 return -EINVAL;
Pavel Begunkov9c280f92020-04-08 08:58:46 +03004205 if (req->flags & REQ_F_FIXED_FILE)
Jens Axboecf3040c2020-02-06 21:31:40 -07004206 return -EBADF;
Jens Axboeb5dba592019-12-11 14:02:38 -07004207
4208 req->close.fd = READ_ONCE(sqe->fd);
Jens Axboe0f212202020-09-13 13:09:39 -06004209 if ((req->file && req->file->f_op == &io_uring_fops))
Jens Axboefd2206e2020-06-02 16:40:47 -06004210 return -EBADF;
4211
Pavel Begunkov3af73b22020-06-08 21:08:17 +03004212 req->close.put_file = NULL;
Jens Axboeb5dba592019-12-11 14:02:38 -07004213 return 0;
4214}
4215
Jens Axboe229a7b62020-06-22 10:13:11 -06004216static int io_close(struct io_kiocb *req, bool force_nonblock,
4217 struct io_comp_state *cs)
Jens Axboeb5dba592019-12-11 14:02:38 -07004218{
Pavel Begunkov3af73b22020-06-08 21:08:17 +03004219 struct io_close *close = &req->close;
Jens Axboeb5dba592019-12-11 14:02:38 -07004220 int ret;
4221
Pavel Begunkov3af73b22020-06-08 21:08:17 +03004222 /* might be already done during nonblock submission */
4223 if (!close->put_file) {
4224 ret = __close_fd_get_file(close->fd, &close->put_file);
4225 if (ret < 0)
4226 return (ret == -ENOENT) ? -EBADF : ret;
4227 }
Jens Axboeb5dba592019-12-11 14:02:38 -07004228
4229 /* if the file has a flush method, be safe and punt to async */
Pavel Begunkov3af73b22020-06-08 21:08:17 +03004230 if (close->put_file->f_op->flush && force_nonblock) {
Pavel Begunkov24c74672020-06-21 13:09:51 +03004231 /* was never set, but play safe */
4232 req->flags &= ~REQ_F_NOWAIT;
Pavel Begunkov0bf0eef2020-05-26 20:34:06 +03004233 /* avoid grabbing files - we don't need the files */
Pavel Begunkov24c74672020-06-21 13:09:51 +03004234 req->flags |= REQ_F_NO_FILE_TABLE;
Pavel Begunkov0bf0eef2020-05-26 20:34:06 +03004235 return -EAGAIN;
Pavel Begunkova2100672020-03-02 23:45:16 +03004236 }
Jens Axboeb5dba592019-12-11 14:02:38 -07004237
Pavel Begunkov3af73b22020-06-08 21:08:17 +03004238 /* No ->flush() or already async, safely close from here */
Jens Axboe98447d62020-10-14 10:48:51 -06004239 ret = filp_close(close->put_file, req->work.identity->files);
Pavel Begunkov3af73b22020-06-08 21:08:17 +03004240 if (ret < 0)
4241 req_set_fail_links(req);
Pavel Begunkov3af73b22020-06-08 21:08:17 +03004242 fput(close->put_file);
4243 close->put_file = NULL;
Jens Axboe229a7b62020-06-22 10:13:11 -06004244 __io_req_complete(req, ret, 0, cs);
Jens Axboe1a417f42020-01-31 17:16:48 -07004245 return 0;
Jens Axboeb5dba592019-12-11 14:02:38 -07004246}
4247
Jens Axboe3529d8c2019-12-19 18:24:38 -07004248static int io_prep_sfr(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboe5d17b4a2019-04-09 14:56:44 -06004249{
4250 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe5d17b4a2019-04-09 14:56:44 -06004251
4252 if (!req->file)
4253 return -EBADF;
Jens Axboe5d17b4a2019-04-09 14:56:44 -06004254
4255 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
4256 return -EINVAL;
4257 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
4258 return -EINVAL;
4259
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004260 req->sync.off = READ_ONCE(sqe->off);
4261 req->sync.len = READ_ONCE(sqe->len);
4262 req->sync.flags = READ_ONCE(sqe->sync_range_flags);
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004263 return 0;
4264}
4265
Pavel Begunkovac45abc2020-06-08 21:08:18 +03004266static int io_sync_file_range(struct io_kiocb *req, bool force_nonblock)
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004267{
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004268 int ret;
4269
Pavel Begunkovac45abc2020-06-08 21:08:18 +03004270 /* sync_file_range always requires a blocking context */
4271 if (force_nonblock)
4272 return -EAGAIN;
4273
Jens Axboe9adbd452019-12-20 08:45:55 -07004274 ret = sync_file_range(req->file, req->sync.off, req->sync.len,
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004275 req->sync.flags);
4276 if (ret < 0)
4277 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06004278 io_req_complete(req, ret);
Jens Axboe5d17b4a2019-04-09 14:56:44 -06004279 return 0;
4280}
4281
YueHaibing469956e2020-03-04 15:53:52 +08004282#if defined(CONFIG_NET)
Pavel Begunkov02d27d82020-02-28 10:36:36 +03004283static int io_setup_async_msg(struct io_kiocb *req,
4284 struct io_async_msghdr *kmsg)
4285{
Jens Axboee8c2bc12020-08-15 18:44:09 -07004286 struct io_async_msghdr *async_msg = req->async_data;
4287
4288 if (async_msg)
Pavel Begunkov02d27d82020-02-28 10:36:36 +03004289 return -EAGAIN;
Jens Axboee8c2bc12020-08-15 18:44:09 -07004290 if (io_alloc_async_data(req)) {
Pavel Begunkov02d27d82020-02-28 10:36:36 +03004291 if (kmsg->iov != kmsg->fast_iov)
4292 kfree(kmsg->iov);
4293 return -ENOMEM;
4294 }
Jens Axboee8c2bc12020-08-15 18:44:09 -07004295 async_msg = req->async_data;
Pavel Begunkov02d27d82020-02-28 10:36:36 +03004296 req->flags |= REQ_F_NEED_CLEANUP;
Jens Axboee8c2bc12020-08-15 18:44:09 -07004297 memcpy(async_msg, kmsg, sizeof(*kmsg));
Pavel Begunkov02d27d82020-02-28 10:36:36 +03004298 return -EAGAIN;
4299}
4300
Pavel Begunkov2ae523e2020-07-12 20:41:06 +03004301static int io_sendmsg_copy_hdr(struct io_kiocb *req,
4302 struct io_async_msghdr *iomsg)
4303{
4304 iomsg->iov = iomsg->fast_iov;
4305 iomsg->msg.msg_name = &iomsg->addr;
4306 return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
4307 req->sr_msg.msg_flags, &iomsg->iov);
4308}
4309
Jens Axboe3529d8c2019-12-19 18:24:38 -07004310static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboeaa1fa282019-04-19 13:38:09 -06004311{
Jens Axboee8c2bc12020-08-15 18:44:09 -07004312 struct io_async_msghdr *async_msg = req->async_data;
Jens Axboee47293f2019-12-20 08:58:21 -07004313 struct io_sr_msg *sr = &req->sr_msg;
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03004314 int ret;
Jens Axboe03b12302019-12-02 18:50:25 -07004315
Pavel Begunkovd2b6f482020-06-03 18:03:25 +03004316 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4317 return -EINVAL;
4318
Jens Axboee47293f2019-12-20 08:58:21 -07004319 sr->msg_flags = READ_ONCE(sqe->msg_flags);
Pavel Begunkov270a5942020-07-12 20:41:04 +03004320 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
Jens Axboefddafac2020-01-04 20:19:44 -07004321 sr->len = READ_ONCE(sqe->len);
Jens Axboe3529d8c2019-12-19 18:24:38 -07004322
Jens Axboed8768362020-02-27 14:17:49 -07004323#ifdef CONFIG_COMPAT
4324 if (req->ctx->compat)
4325 sr->msg_flags |= MSG_CMSG_COMPAT;
4326#endif
4327
Jens Axboee8c2bc12020-08-15 18:44:09 -07004328 if (!async_msg || !io_op_defs[req->opcode].needs_async_data)
Jens Axboe3529d8c2019-12-19 18:24:38 -07004329 return 0;
Jens Axboee8c2bc12020-08-15 18:44:09 -07004330 ret = io_sendmsg_copy_hdr(req, async_msg);
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03004331 if (!ret)
4332 req->flags |= REQ_F_NEED_CLEANUP;
4333 return ret;
Jens Axboe03b12302019-12-02 18:50:25 -07004334}
4335
Jens Axboe229a7b62020-06-22 10:13:11 -06004336static int io_sendmsg(struct io_kiocb *req, bool force_nonblock,
4337 struct io_comp_state *cs)
Jens Axboe03b12302019-12-02 18:50:25 -07004338{
Pavel Begunkov6b754c82020-07-16 23:28:00 +03004339 struct io_async_msghdr iomsg, *kmsg;
Jens Axboe03b12302019-12-02 18:50:25 -07004340 struct socket *sock;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004341 unsigned flags;
Jens Axboe03b12302019-12-02 18:50:25 -07004342 int ret;
4343
Jens Axboe03b12302019-12-02 18:50:25 -07004344 sock = sock_from_file(req->file, &ret);
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004345 if (unlikely(!sock))
4346 return ret;
Jens Axboe03b12302019-12-02 18:50:25 -07004347
Jens Axboee8c2bc12020-08-15 18:44:09 -07004348 if (req->async_data) {
4349 kmsg = req->async_data;
4350 kmsg->msg.msg_name = &kmsg->addr;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004351 /* if iov is set, it's allocated already */
4352 if (!kmsg->iov)
4353 kmsg->iov = kmsg->fast_iov;
4354 kmsg->msg.msg_iter.iov = kmsg->iov;
4355 } else {
4356 ret = io_sendmsg_copy_hdr(req, &iomsg);
Jens Axboefddafac2020-01-04 20:19:44 -07004357 if (ret)
4358 return ret;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004359 kmsg = &iomsg;
Jens Axboefddafac2020-01-04 20:19:44 -07004360 }
4361
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004362 flags = req->sr_msg.msg_flags;
4363 if (flags & MSG_DONTWAIT)
4364 req->flags |= REQ_F_NOWAIT;
4365 else if (force_nonblock)
4366 flags |= MSG_DONTWAIT;
4367
4368 ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
4369 if (force_nonblock && ret == -EAGAIN)
4370 return io_setup_async_msg(req, kmsg);
4371 if (ret == -ERESTARTSYS)
4372 ret = -EINTR;
4373
Pavel Begunkov6b754c82020-07-16 23:28:00 +03004374 if (kmsg->iov != kmsg->fast_iov)
Jens Axboe03b12302019-12-02 18:50:25 -07004375 kfree(kmsg->iov);
4376 req->flags &= ~REQ_F_NEED_CLEANUP;
Jens Axboefddafac2020-01-04 20:19:44 -07004377 if (ret < 0)
4378 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06004379 __io_req_complete(req, ret, 0, cs);
Jens Axboefddafac2020-01-04 20:19:44 -07004380 return 0;
Jens Axboefddafac2020-01-04 20:19:44 -07004381}
4382
Jens Axboe229a7b62020-06-22 10:13:11 -06004383static int io_send(struct io_kiocb *req, bool force_nonblock,
4384 struct io_comp_state *cs)
Jens Axboe03b12302019-12-02 18:50:25 -07004385{
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004386 struct io_sr_msg *sr = &req->sr_msg;
4387 struct msghdr msg;
4388 struct iovec iov;
Jens Axboe03b12302019-12-02 18:50:25 -07004389 struct socket *sock;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004390 unsigned flags;
Jens Axboe03b12302019-12-02 18:50:25 -07004391 int ret;
4392
4393 sock = sock_from_file(req->file, &ret);
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004394 if (unlikely(!sock))
4395 return ret;
Jens Axboe03b12302019-12-02 18:50:25 -07004396
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004397 ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
4398 if (unlikely(ret))
Zheng Bin14db8412020-09-09 20:12:37 +08004399 return ret;
Jens Axboe03b12302019-12-02 18:50:25 -07004400
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004401 msg.msg_name = NULL;
4402 msg.msg_control = NULL;
4403 msg.msg_controllen = 0;
4404 msg.msg_namelen = 0;
Jens Axboe03b12302019-12-02 18:50:25 -07004405
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004406 flags = req->sr_msg.msg_flags;
4407 if (flags & MSG_DONTWAIT)
4408 req->flags |= REQ_F_NOWAIT;
4409 else if (force_nonblock)
4410 flags |= MSG_DONTWAIT;
Jens Axboe03b12302019-12-02 18:50:25 -07004411
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004412 msg.msg_flags = flags;
4413 ret = sock_sendmsg(sock, &msg);
4414 if (force_nonblock && ret == -EAGAIN)
4415 return -EAGAIN;
4416 if (ret == -ERESTARTSYS)
4417 ret = -EINTR;
Jens Axboe03b12302019-12-02 18:50:25 -07004418
Jens Axboe03b12302019-12-02 18:50:25 -07004419 if (ret < 0)
4420 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06004421 __io_req_complete(req, ret, 0, cs);
Jens Axboe03b12302019-12-02 18:50:25 -07004422 return 0;
Jens Axboe03b12302019-12-02 18:50:25 -07004423}
4424
Pavel Begunkov1400e692020-07-12 20:41:05 +03004425static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
4426 struct io_async_msghdr *iomsg)
Jens Axboe52de1fe2020-02-27 10:15:42 -07004427{
4428 struct io_sr_msg *sr = &req->sr_msg;
4429 struct iovec __user *uiov;
4430 size_t iov_len;
4431 int ret;
4432
Pavel Begunkov1400e692020-07-12 20:41:05 +03004433 ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
4434 &iomsg->uaddr, &uiov, &iov_len);
Jens Axboe52de1fe2020-02-27 10:15:42 -07004435 if (ret)
4436 return ret;
4437
4438 if (req->flags & REQ_F_BUFFER_SELECT) {
4439 if (iov_len > 1)
4440 return -EINVAL;
Pavel Begunkov1400e692020-07-12 20:41:05 +03004441 if (copy_from_user(iomsg->iov, uiov, sizeof(*uiov)))
Jens Axboe52de1fe2020-02-27 10:15:42 -07004442 return -EFAULT;
Pavel Begunkov1400e692020-07-12 20:41:05 +03004443 sr->len = iomsg->iov[0].iov_len;
4444 iov_iter_init(&iomsg->msg.msg_iter, READ, iomsg->iov, 1,
Jens Axboe52de1fe2020-02-27 10:15:42 -07004445 sr->len);
Pavel Begunkov1400e692020-07-12 20:41:05 +03004446 iomsg->iov = NULL;
Jens Axboe52de1fe2020-02-27 10:15:42 -07004447 } else {
Christoph Hellwig89cd35c2020-09-25 06:51:41 +02004448 ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
4449 &iomsg->iov, &iomsg->msg.msg_iter,
4450 false);
Jens Axboe52de1fe2020-02-27 10:15:42 -07004451 if (ret > 0)
4452 ret = 0;
4453 }
4454
4455 return ret;
4456}
4457
4458#ifdef CONFIG_COMPAT
4459static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
Pavel Begunkov1400e692020-07-12 20:41:05 +03004460 struct io_async_msghdr *iomsg)
Jens Axboe52de1fe2020-02-27 10:15:42 -07004461{
4462 struct compat_msghdr __user *msg_compat;
4463 struct io_sr_msg *sr = &req->sr_msg;
4464 struct compat_iovec __user *uiov;
4465 compat_uptr_t ptr;
4466 compat_size_t len;
4467 int ret;
4468
Pavel Begunkov270a5942020-07-12 20:41:04 +03004469 msg_compat = (struct compat_msghdr __user *) sr->umsg;
Pavel Begunkov1400e692020-07-12 20:41:05 +03004470 ret = __get_compat_msghdr(&iomsg->msg, msg_compat, &iomsg->uaddr,
Jens Axboe52de1fe2020-02-27 10:15:42 -07004471 &ptr, &len);
4472 if (ret)
4473 return ret;
4474
4475 uiov = compat_ptr(ptr);
4476 if (req->flags & REQ_F_BUFFER_SELECT) {
4477 compat_ssize_t clen;
4478
4479 if (len > 1)
4480 return -EINVAL;
4481 if (!access_ok(uiov, sizeof(*uiov)))
4482 return -EFAULT;
4483 if (__get_user(clen, &uiov->iov_len))
4484 return -EFAULT;
4485 if (clen < 0)
4486 return -EINVAL;
Pavel Begunkov1400e692020-07-12 20:41:05 +03004487 sr->len = iomsg->iov[0].iov_len;
4488 iomsg->iov = NULL;
Jens Axboe52de1fe2020-02-27 10:15:42 -07004489 } else {
Christoph Hellwig89cd35c2020-09-25 06:51:41 +02004490 ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
4491 UIO_FASTIOV, &iomsg->iov,
4492 &iomsg->msg.msg_iter, true);
Jens Axboe52de1fe2020-02-27 10:15:42 -07004493 if (ret < 0)
4494 return ret;
4495 }
4496
4497 return 0;
4498}
Jens Axboe03b12302019-12-02 18:50:25 -07004499#endif
Jens Axboe52de1fe2020-02-27 10:15:42 -07004500
Pavel Begunkov1400e692020-07-12 20:41:05 +03004501static int io_recvmsg_copy_hdr(struct io_kiocb *req,
4502 struct io_async_msghdr *iomsg)
Jens Axboe52de1fe2020-02-27 10:15:42 -07004503{
Pavel Begunkov1400e692020-07-12 20:41:05 +03004504 iomsg->msg.msg_name = &iomsg->addr;
4505 iomsg->iov = iomsg->fast_iov;
Jens Axboe52de1fe2020-02-27 10:15:42 -07004506
4507#ifdef CONFIG_COMPAT
4508 if (req->ctx->compat)
Pavel Begunkov1400e692020-07-12 20:41:05 +03004509 return __io_compat_recvmsg_copy_hdr(req, iomsg);
Jens Axboe52de1fe2020-02-27 10:15:42 -07004510#endif
4511
Pavel Begunkov1400e692020-07-12 20:41:05 +03004512 return __io_recvmsg_copy_hdr(req, iomsg);
Jens Axboe52de1fe2020-02-27 10:15:42 -07004513}
4514
Jens Axboebcda7ba2020-02-23 16:42:51 -07004515static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
Pavel Begunkov7fbb1b52020-07-16 23:28:05 +03004516 bool needs_lock)
Jens Axboebcda7ba2020-02-23 16:42:51 -07004517{
4518 struct io_sr_msg *sr = &req->sr_msg;
4519 struct io_buffer *kbuf;
4520
Jens Axboebcda7ba2020-02-23 16:42:51 -07004521 kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
4522 if (IS_ERR(kbuf))
4523 return kbuf;
4524
4525 sr->kbuf = kbuf;
4526 req->flags |= REQ_F_BUFFER_SELECTED;
Jens Axboebcda7ba2020-02-23 16:42:51 -07004527 return kbuf;
Jens Axboe03b12302019-12-02 18:50:25 -07004528}
4529
Pavel Begunkov7fbb1b52020-07-16 23:28:05 +03004530static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
4531{
4532 return io_put_kbuf(req, req->sr_msg.kbuf);
4533}
4534
Jens Axboe3529d8c2019-12-19 18:24:38 -07004535static int io_recvmsg_prep(struct io_kiocb *req,
4536 const struct io_uring_sqe *sqe)
Jens Axboe03b12302019-12-02 18:50:25 -07004537{
Jens Axboee8c2bc12020-08-15 18:44:09 -07004538 struct io_async_msghdr *async_msg = req->async_data;
Jens Axboee47293f2019-12-20 08:58:21 -07004539 struct io_sr_msg *sr = &req->sr_msg;
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03004540 int ret;
Jens Axboe06b76d42019-12-19 14:44:26 -07004541
Pavel Begunkovd2b6f482020-06-03 18:03:25 +03004542 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4543 return -EINVAL;
4544
Jens Axboe3529d8c2019-12-19 18:24:38 -07004545 sr->msg_flags = READ_ONCE(sqe->msg_flags);
Pavel Begunkov270a5942020-07-12 20:41:04 +03004546 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
Jens Axboe0b7b21e2020-01-31 08:34:59 -07004547 sr->len = READ_ONCE(sqe->len);
Jens Axboebcda7ba2020-02-23 16:42:51 -07004548 sr->bgid = READ_ONCE(sqe->buf_group);
Jens Axboe3529d8c2019-12-19 18:24:38 -07004549
Jens Axboed8768362020-02-27 14:17:49 -07004550#ifdef CONFIG_COMPAT
4551 if (req->ctx->compat)
4552 sr->msg_flags |= MSG_CMSG_COMPAT;
4553#endif
4554
Jens Axboee8c2bc12020-08-15 18:44:09 -07004555 if (!async_msg || !io_op_defs[req->opcode].needs_async_data)
Jens Axboe06b76d42019-12-19 14:44:26 -07004556 return 0;
Jens Axboee8c2bc12020-08-15 18:44:09 -07004557 ret = io_recvmsg_copy_hdr(req, async_msg);
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03004558 if (!ret)
4559 req->flags |= REQ_F_NEED_CLEANUP;
4560 return ret;
Jens Axboe03b12302019-12-02 18:50:25 -07004561}
4562
Jens Axboe229a7b62020-06-22 10:13:11 -06004563static int io_recvmsg(struct io_kiocb *req, bool force_nonblock,
4564 struct io_comp_state *cs)
Jens Axboe03b12302019-12-02 18:50:25 -07004565{
Pavel Begunkov6b754c82020-07-16 23:28:00 +03004566 struct io_async_msghdr iomsg, *kmsg;
Jens Axboe0fa03c62019-04-19 13:34:07 -06004567 struct socket *sock;
Pavel Begunkov7fbb1b52020-07-16 23:28:05 +03004568 struct io_buffer *kbuf;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004569 unsigned flags;
Jens Axboe52de1fe2020-02-27 10:15:42 -07004570 int ret, cflags = 0;
Jens Axboe0fa03c62019-04-19 13:34:07 -06004571
Jens Axboe0fa03c62019-04-19 13:34:07 -06004572 sock = sock_from_file(req->file, &ret);
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004573 if (unlikely(!sock))
4574 return ret;
Jens Axboe0fa03c62019-04-19 13:34:07 -06004575
Jens Axboee8c2bc12020-08-15 18:44:09 -07004576 if (req->async_data) {
4577 kmsg = req->async_data;
4578 kmsg->msg.msg_name = &kmsg->addr;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004579 /* if iov is set, it's allocated already */
4580 if (!kmsg->iov)
4581 kmsg->iov = kmsg->fast_iov;
4582 kmsg->msg.msg_iter.iov = kmsg->iov;
4583 } else {
4584 ret = io_recvmsg_copy_hdr(req, &iomsg);
4585 if (ret)
Pavel Begunkov681fda82020-07-15 22:20:45 +03004586 return ret;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004587 kmsg = &iomsg;
Jens Axboe0fa03c62019-04-19 13:34:07 -06004588 }
4589
Pavel Begunkovbc02ef32020-07-16 23:28:03 +03004590 if (req->flags & REQ_F_BUFFER_SELECT) {
Pavel Begunkov7fbb1b52020-07-16 23:28:05 +03004591 kbuf = io_recv_buffer_select(req, !force_nonblock);
Pavel Begunkovbc02ef32020-07-16 23:28:03 +03004592 if (IS_ERR(kbuf))
4593 return PTR_ERR(kbuf);
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004594 kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
4595 iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->iov,
4596 1, req->sr_msg.len);
4597 }
4598
4599 flags = req->sr_msg.msg_flags;
4600 if (flags & MSG_DONTWAIT)
4601 req->flags |= REQ_F_NOWAIT;
4602 else if (force_nonblock)
4603 flags |= MSG_DONTWAIT;
4604
4605 ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
4606 kmsg->uaddr, flags);
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03004607 if (force_nonblock && ret == -EAGAIN)
4608 return io_setup_async_msg(req, kmsg);
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004609 if (ret == -ERESTARTSYS)
4610 ret = -EINTR;
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03004611
Pavel Begunkov7fbb1b52020-07-16 23:28:05 +03004612 if (req->flags & REQ_F_BUFFER_SELECTED)
4613 cflags = io_put_recv_kbuf(req);
Pavel Begunkov6b754c82020-07-16 23:28:00 +03004614 if (kmsg->iov != kmsg->fast_iov)
Jens Axboe0b416c32019-12-15 10:57:46 -07004615 kfree(kmsg->iov);
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03004616 req->flags &= ~REQ_F_NEED_CLEANUP;
Jens Axboe4e88d6e2019-12-07 20:59:47 -07004617 if (ret < 0)
4618 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06004619 __io_req_complete(req, ret, cflags, cs);
Jens Axboe0fa03c62019-04-19 13:34:07 -06004620 return 0;
Jens Axboe0fa03c62019-04-19 13:34:07 -06004621}
4622
Jens Axboe229a7b62020-06-22 10:13:11 -06004623static int io_recv(struct io_kiocb *req, bool force_nonblock,
4624 struct io_comp_state *cs)
Jens Axboefddafac2020-01-04 20:19:44 -07004625{
Pavel Begunkov6b754c82020-07-16 23:28:00 +03004626 struct io_buffer *kbuf;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004627 struct io_sr_msg *sr = &req->sr_msg;
4628 struct msghdr msg;
4629 void __user *buf = sr->buf;
Jens Axboefddafac2020-01-04 20:19:44 -07004630 struct socket *sock;
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004631 struct iovec iov;
4632 unsigned flags;
Jens Axboebcda7ba2020-02-23 16:42:51 -07004633 int ret, cflags = 0;
Jens Axboefddafac2020-01-04 20:19:44 -07004634
Jens Axboefddafac2020-01-04 20:19:44 -07004635 sock = sock_from_file(req->file, &ret);
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004636 if (unlikely(!sock))
4637 return ret;
Jens Axboefddafac2020-01-04 20:19:44 -07004638
Pavel Begunkovbc02ef32020-07-16 23:28:03 +03004639 if (req->flags & REQ_F_BUFFER_SELECT) {
Pavel Begunkov7fbb1b52020-07-16 23:28:05 +03004640 kbuf = io_recv_buffer_select(req, !force_nonblock);
Jens Axboebcda7ba2020-02-23 16:42:51 -07004641 if (IS_ERR(kbuf))
4642 return PTR_ERR(kbuf);
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004643 buf = u64_to_user_ptr(kbuf->addr);
Jens Axboefddafac2020-01-04 20:19:44 -07004644 }
4645
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004646 ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
Pavel Begunkov14c32ee2020-07-16 23:28:01 +03004647 if (unlikely(ret))
4648 goto out_free;
Jens Axboefddafac2020-01-04 20:19:44 -07004649
Pavel Begunkov7a7cacb2020-07-16 23:27:59 +03004650 msg.msg_name = NULL;
4651 msg.msg_control = NULL;
4652 msg.msg_controllen = 0;
4653 msg.msg_namelen = 0;
4654 msg.msg_iocb = NULL;
4655 msg.msg_flags = 0;
4656
4657 flags = req->sr_msg.msg_flags;
4658 if (flags & MSG_DONTWAIT)
4659 req->flags |= REQ_F_NOWAIT;
4660 else if (force_nonblock)
4661 flags |= MSG_DONTWAIT;
4662
4663 ret = sock_recvmsg(sock, &msg, flags);
4664 if (force_nonblock && ret == -EAGAIN)
4665 return -EAGAIN;
4666 if (ret == -ERESTARTSYS)
4667 ret = -EINTR;
Pavel Begunkov14c32ee2020-07-16 23:28:01 +03004668out_free:
Pavel Begunkov7fbb1b52020-07-16 23:28:05 +03004669 if (req->flags & REQ_F_BUFFER_SELECTED)
4670 cflags = io_put_recv_kbuf(req);
Jens Axboefddafac2020-01-04 20:19:44 -07004671 if (ret < 0)
4672 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06004673 __io_req_complete(req, ret, cflags, cs);
Jens Axboefddafac2020-01-04 20:19:44 -07004674 return 0;
Jens Axboefddafac2020-01-04 20:19:44 -07004675}
4676
Jens Axboe3529d8c2019-12-19 18:24:38 -07004677static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboe17f2fe32019-10-17 14:42:58 -06004678{
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004679 struct io_accept *accept = &req->accept;
4680
Jens Axboe17f2fe32019-10-17 14:42:58 -06004681 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
4682 return -EINVAL;
Hrvoje Zeba8042d6c2019-11-25 14:40:22 -05004683 if (sqe->ioprio || sqe->len || sqe->buf_index)
Jens Axboe17f2fe32019-10-17 14:42:58 -06004684 return -EINVAL;
4685
Jens Axboed55e5f52019-12-11 16:12:15 -07004686 accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
4687 accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004688 accept->flags = READ_ONCE(sqe->accept_flags);
Jens Axboe09952e32020-03-19 20:16:56 -06004689 accept->nofile = rlimit(RLIMIT_NOFILE);
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004690 return 0;
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004691}
Jens Axboe17f2fe32019-10-17 14:42:58 -06004692
Jens Axboe229a7b62020-06-22 10:13:11 -06004693static int io_accept(struct io_kiocb *req, bool force_nonblock,
4694 struct io_comp_state *cs)
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004695{
4696 struct io_accept *accept = &req->accept;
Pavel Begunkovac45abc2020-06-08 21:08:18 +03004697 unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004698 int ret;
4699
Jiufei Xuee697dee2020-06-10 13:41:59 +08004700 if (req->file->f_flags & O_NONBLOCK)
4701 req->flags |= REQ_F_NOWAIT;
4702
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004703 ret = __sys_accept4_file(req->file, file_flags, accept->addr,
Jens Axboe09952e32020-03-19 20:16:56 -06004704 accept->addr_len, accept->flags,
4705 accept->nofile);
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004706 if (ret == -EAGAIN && force_nonblock)
Jens Axboe17f2fe32019-10-17 14:42:58 -06004707 return -EAGAIN;
Pavel Begunkovac45abc2020-06-08 21:08:18 +03004708 if (ret < 0) {
4709 if (ret == -ERESTARTSYS)
4710 ret = -EINTR;
Jens Axboe4e88d6e2019-12-07 20:59:47 -07004711 req_set_fail_links(req);
Pavel Begunkovac45abc2020-06-08 21:08:18 +03004712 }
Jens Axboe229a7b62020-06-22 10:13:11 -06004713 __io_req_complete(req, ret, 0, cs);
Jens Axboe17f2fe32019-10-17 14:42:58 -06004714 return 0;
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07004715}
4716
Jens Axboe3529d8c2019-12-19 18:24:38 -07004717static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboef499a022019-12-02 16:28:46 -07004718{
Jens Axboe3529d8c2019-12-19 18:24:38 -07004719 struct io_connect *conn = &req->connect;
Jens Axboee8c2bc12020-08-15 18:44:09 -07004720 struct io_async_connect *io = req->async_data;
Jens Axboef499a022019-12-02 16:28:46 -07004721
Jens Axboe3fbb51c2019-12-20 08:51:52 -07004722 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))
4723 return -EINVAL;
4724 if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags)
4725 return -EINVAL;
4726
Jens Axboe3529d8c2019-12-19 18:24:38 -07004727 conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
4728 conn->addr_len = READ_ONCE(sqe->addr2);
4729
4730 if (!io)
4731 return 0;
4732
4733 return move_addr_to_kernel(conn->addr, conn->addr_len,
Jens Axboee8c2bc12020-08-15 18:44:09 -07004734 &io->address);
Jens Axboef499a022019-12-02 16:28:46 -07004735}
4736
Jens Axboe229a7b62020-06-22 10:13:11 -06004737static int io_connect(struct io_kiocb *req, bool force_nonblock,
4738 struct io_comp_state *cs)
Jens Axboef8e85cf2019-11-23 14:24:24 -07004739{
Jens Axboee8c2bc12020-08-15 18:44:09 -07004740 struct io_async_connect __io, *io;
Jens Axboef8e85cf2019-11-23 14:24:24 -07004741 unsigned file_flags;
Jens Axboe3fbb51c2019-12-20 08:51:52 -07004742 int ret;
Jens Axboef8e85cf2019-11-23 14:24:24 -07004743
Jens Axboee8c2bc12020-08-15 18:44:09 -07004744 if (req->async_data) {
4745 io = req->async_data;
Jens Axboef499a022019-12-02 16:28:46 -07004746 } else {
Jens Axboe3529d8c2019-12-19 18:24:38 -07004747 ret = move_addr_to_kernel(req->connect.addr,
4748 req->connect.addr_len,
Jens Axboee8c2bc12020-08-15 18:44:09 -07004749 &__io.address);
Jens Axboef499a022019-12-02 16:28:46 -07004750 if (ret)
4751 goto out;
4752 io = &__io;
4753 }
4754
Jens Axboe3fbb51c2019-12-20 08:51:52 -07004755 file_flags = force_nonblock ? O_NONBLOCK : 0;
4756
Jens Axboee8c2bc12020-08-15 18:44:09 -07004757 ret = __sys_connect_file(req->file, &io->address,
Jens Axboe3fbb51c2019-12-20 08:51:52 -07004758 req->connect.addr_len, file_flags);
Jens Axboe87f80d62019-12-03 11:23:54 -07004759 if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
Jens Axboee8c2bc12020-08-15 18:44:09 -07004760 if (req->async_data)
Jens Axboeb7bb4f72019-12-15 22:13:43 -07004761 return -EAGAIN;
Jens Axboee8c2bc12020-08-15 18:44:09 -07004762 if (io_alloc_async_data(req)) {
Jens Axboef499a022019-12-02 16:28:46 -07004763 ret = -ENOMEM;
4764 goto out;
4765 }
Jens Axboee8c2bc12020-08-15 18:44:09 -07004766 io = req->async_data;
4767 memcpy(req->async_data, &__io, sizeof(__io));
Jens Axboef8e85cf2019-11-23 14:24:24 -07004768 return -EAGAIN;
Jens Axboef499a022019-12-02 16:28:46 -07004769 }
Jens Axboef8e85cf2019-11-23 14:24:24 -07004770 if (ret == -ERESTARTSYS)
4771 ret = -EINTR;
Jens Axboef499a022019-12-02 16:28:46 -07004772out:
Jens Axboe4e88d6e2019-12-07 20:59:47 -07004773 if (ret < 0)
4774 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06004775 __io_req_complete(req, ret, 0, cs);
Jens Axboef8e85cf2019-11-23 14:24:24 -07004776 return 0;
Jens Axboef8e85cf2019-11-23 14:24:24 -07004777}
YueHaibing469956e2020-03-04 15:53:52 +08004778#else /* !CONFIG_NET */
4779static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4780{
Jens Axboef8e85cf2019-11-23 14:24:24 -07004781 return -EOPNOTSUPP;
Jens Axboef8e85cf2019-11-23 14:24:24 -07004782}
4783
Randy Dunlap1e16c2f2020-06-26 16:32:50 -07004784static int io_sendmsg(struct io_kiocb *req, bool force_nonblock,
4785 struct io_comp_state *cs)
Jens Axboe221c5eb2019-01-17 09:41:58 -07004786{
YueHaibing469956e2020-03-04 15:53:52 +08004787 return -EOPNOTSUPP;
4788}
4789
Randy Dunlap1e16c2f2020-06-26 16:32:50 -07004790static int io_send(struct io_kiocb *req, bool force_nonblock,
4791 struct io_comp_state *cs)
YueHaibing469956e2020-03-04 15:53:52 +08004792{
4793 return -EOPNOTSUPP;
4794}
4795
4796static int io_recvmsg_prep(struct io_kiocb *req,
4797 const struct io_uring_sqe *sqe)
4798{
4799 return -EOPNOTSUPP;
4800}
4801
Randy Dunlap1e16c2f2020-06-26 16:32:50 -07004802static int io_recvmsg(struct io_kiocb *req, bool force_nonblock,
4803 struct io_comp_state *cs)
YueHaibing469956e2020-03-04 15:53:52 +08004804{
4805 return -EOPNOTSUPP;
4806}
4807
Randy Dunlap1e16c2f2020-06-26 16:32:50 -07004808static int io_recv(struct io_kiocb *req, bool force_nonblock,
4809 struct io_comp_state *cs)
YueHaibing469956e2020-03-04 15:53:52 +08004810{
4811 return -EOPNOTSUPP;
4812}
4813
4814static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4815{
4816 return -EOPNOTSUPP;
4817}
4818
Randy Dunlap1e16c2f2020-06-26 16:32:50 -07004819static int io_accept(struct io_kiocb *req, bool force_nonblock,
4820 struct io_comp_state *cs)
YueHaibing469956e2020-03-04 15:53:52 +08004821{
4822 return -EOPNOTSUPP;
4823}
4824
4825static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4826{
4827 return -EOPNOTSUPP;
4828}
4829
Randy Dunlap1e16c2f2020-06-26 16:32:50 -07004830static int io_connect(struct io_kiocb *req, bool force_nonblock,
4831 struct io_comp_state *cs)
YueHaibing469956e2020-03-04 15:53:52 +08004832{
4833 return -EOPNOTSUPP;
4834}
4835#endif /* CONFIG_NET */
Jens Axboe2b188cc2019-01-07 10:46:33 -07004836
Jens Axboed7718a92020-02-14 22:23:12 -07004837struct io_poll_table {
4838 struct poll_table_struct pt;
4839 struct io_kiocb *req;
4840 int error;
4841};
4842
Jens Axboed7718a92020-02-14 22:23:12 -07004843static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll,
4844 __poll_t mask, task_work_func_t func)
4845{
Jens Axboeaa96bf82020-04-03 11:26:26 -06004846 int ret;
Jens Axboed7718a92020-02-14 22:23:12 -07004847
4848 /* for instances that support it check for an event match first: */
4849 if (mask && !(mask & poll->events))
4850 return 0;
4851
4852 trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
4853
4854 list_del_init(&poll->wait.entry);
4855
Jens Axboed7718a92020-02-14 22:23:12 -07004856 req->result = mask;
4857 init_task_work(&req->task_work, func);
Jens Axboe6d816e02020-08-11 08:04:14 -06004858 percpu_ref_get(&req->ctx->refs);
4859
Jens Axboed7718a92020-02-14 22:23:12 -07004860 /*
Jens Axboee3aabf92020-05-18 11:04:17 -06004861 * If this fails, then the task is exiting. When a task exits, the
4862 * work gets canceled, so just cancel this request as well instead
4863 * of executing it. We can't safely execute it anyway, as we may not
4864 * have the needed state needed for it anyway.
Jens Axboed7718a92020-02-14 22:23:12 -07004865 */
Jens Axboe355fb9e2020-10-22 20:19:35 -06004866 ret = io_req_task_work_add(req);
Jens Axboeaa96bf82020-04-03 11:26:26 -06004867 if (unlikely(ret)) {
Jens Axboec2c4c832020-07-01 15:37:11 -06004868 struct task_struct *tsk;
4869
Jens Axboee3aabf92020-05-18 11:04:17 -06004870 WRITE_ONCE(poll->canceled, true);
Jens Axboeaa96bf82020-04-03 11:26:26 -06004871 tsk = io_wq_get_task(req->ctx->io_wq);
Jens Axboe91989c72020-10-16 09:02:26 -06004872 task_work_add(tsk, &req->task_work, TWA_NONE);
Jens Axboece593a62020-06-30 12:39:05 -06004873 wake_up_process(tsk);
Jens Axboeaa96bf82020-04-03 11:26:26 -06004874 }
Jens Axboed7718a92020-02-14 22:23:12 -07004875 return 1;
4876}
4877
Jens Axboe74ce6ce2020-04-13 11:09:12 -06004878static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
4879 __acquires(&req->ctx->completion_lock)
4880{
4881 struct io_ring_ctx *ctx = req->ctx;
4882
4883 if (!req->result && !READ_ONCE(poll->canceled)) {
4884 struct poll_table_struct pt = { ._key = poll->events };
4885
4886 req->result = vfs_poll(req->file, &pt) & poll->events;
4887 }
4888
4889 spin_lock_irq(&ctx->completion_lock);
4890 if (!req->result && !READ_ONCE(poll->canceled)) {
4891 add_wait_queue(poll->head, &poll->wait);
4892 return true;
4893 }
4894
4895 return false;
4896}
4897
Jens Axboed4e7cd32020-08-15 11:44:50 -07004898static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
Jens Axboe18bceab2020-05-15 11:56:54 -06004899{
Jens Axboee8c2bc12020-08-15 18:44:09 -07004900 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
Jens Axboed4e7cd32020-08-15 11:44:50 -07004901 if (req->opcode == IORING_OP_POLL_ADD)
Jens Axboee8c2bc12020-08-15 18:44:09 -07004902 return req->async_data;
Jens Axboed4e7cd32020-08-15 11:44:50 -07004903 return req->apoll->double_poll;
4904}
4905
4906static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
4907{
4908 if (req->opcode == IORING_OP_POLL_ADD)
4909 return &req->poll;
4910 return &req->apoll->poll;
4911}
4912
4913static void io_poll_remove_double(struct io_kiocb *req)
4914{
4915 struct io_poll_iocb *poll = io_poll_get_double(req);
Jens Axboe18bceab2020-05-15 11:56:54 -06004916
4917 lockdep_assert_held(&req->ctx->completion_lock);
4918
4919 if (poll && poll->head) {
4920 struct wait_queue_head *head = poll->head;
4921
4922 spin_lock(&head->lock);
4923 list_del_init(&poll->wait.entry);
4924 if (poll->wait.private)
4925 refcount_dec(&req->refs);
4926 poll->head = NULL;
4927 spin_unlock(&head->lock);
4928 }
4929}
4930
4931static void io_poll_complete(struct io_kiocb *req, __poll_t mask, int error)
4932{
4933 struct io_ring_ctx *ctx = req->ctx;
4934
Jens Axboed4e7cd32020-08-15 11:44:50 -07004935 io_poll_remove_double(req);
Jens Axboe18bceab2020-05-15 11:56:54 -06004936 req->poll.done = true;
4937 io_cqring_fill_event(req, error ? error : mangle_poll(mask));
4938 io_commit_cqring(ctx);
4939}
4940
Jens Axboe18bceab2020-05-15 11:56:54 -06004941static void io_poll_task_func(struct callback_head *cb)
4942{
4943 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
Jens Axboe6d816e02020-08-11 08:04:14 -06004944 struct io_ring_ctx *ctx = req->ctx;
Pavel Begunkovdd221f462020-10-18 10:17:42 +01004945 struct io_kiocb *nxt;
Jens Axboe18bceab2020-05-15 11:56:54 -06004946
Pavel Begunkovdd221f462020-10-18 10:17:42 +01004947 if (io_poll_rewait(req, &req->poll)) {
4948 spin_unlock_irq(&ctx->completion_lock);
4949 } else {
4950 hash_del(&req->hash_node);
4951 io_poll_complete(req, req->result, 0);
4952 spin_unlock_irq(&ctx->completion_lock);
4953
4954 nxt = io_put_req_find_next(req);
4955 io_cqring_ev_posted(ctx);
4956 if (nxt)
4957 __io_req_task_submit(nxt);
4958 }
4959
Jens Axboe6d816e02020-08-11 08:04:14 -06004960 percpu_ref_put(&ctx->refs);
Jens Axboe18bceab2020-05-15 11:56:54 -06004961}
4962
4963static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode,
4964 int sync, void *key)
4965{
4966 struct io_kiocb *req = wait->private;
Jens Axboed4e7cd32020-08-15 11:44:50 -07004967 struct io_poll_iocb *poll = io_poll_get_single(req);
Jens Axboe18bceab2020-05-15 11:56:54 -06004968 __poll_t mask = key_to_poll(key);
4969
4970 /* for instances that support it check for an event match first: */
4971 if (mask && !(mask & poll->events))
4972 return 0;
4973
Jens Axboe8706e042020-09-28 08:38:54 -06004974 list_del_init(&wait->entry);
4975
Jens Axboe807abcb2020-07-17 17:09:27 -06004976 if (poll && poll->head) {
Jens Axboe18bceab2020-05-15 11:56:54 -06004977 bool done;
4978
Jens Axboe807abcb2020-07-17 17:09:27 -06004979 spin_lock(&poll->head->lock);
4980 done = list_empty(&poll->wait.entry);
Jens Axboe18bceab2020-05-15 11:56:54 -06004981 if (!done)
Jens Axboe807abcb2020-07-17 17:09:27 -06004982 list_del_init(&poll->wait.entry);
Jens Axboed4e7cd32020-08-15 11:44:50 -07004983 /* make sure double remove sees this as being gone */
4984 wait->private = NULL;
Jens Axboe807abcb2020-07-17 17:09:27 -06004985 spin_unlock(&poll->head->lock);
Jens Axboec8b5e262020-10-25 13:53:26 -06004986 if (!done) {
4987 /* use wait func handler, so it matches the rq type */
4988 poll->wait.func(&poll->wait, mode, sync, key);
4989 }
Jens Axboe18bceab2020-05-15 11:56:54 -06004990 }
4991 refcount_dec(&req->refs);
4992 return 1;
4993}
4994
4995static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
4996 wait_queue_func_t wake_func)
4997{
4998 poll->head = NULL;
4999 poll->done = false;
5000 poll->canceled = false;
5001 poll->events = events;
5002 INIT_LIST_HEAD(&poll->wait.entry);
5003 init_waitqueue_func_entry(&poll->wait, wake_func);
5004}
5005
5006static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
Jens Axboe807abcb2020-07-17 17:09:27 -06005007 struct wait_queue_head *head,
5008 struct io_poll_iocb **poll_ptr)
Jens Axboe18bceab2020-05-15 11:56:54 -06005009{
5010 struct io_kiocb *req = pt->req;
5011
5012 /*
5013 * If poll->head is already set, it's because the file being polled
5014 * uses multiple waitqueues for poll handling (eg one for read, one
5015 * for write). Setup a separate io_poll_iocb if this happens.
5016 */
5017 if (unlikely(poll->head)) {
Pavel Begunkov58852d42020-10-16 20:55:56 +01005018 struct io_poll_iocb *poll_one = poll;
5019
Jens Axboe18bceab2020-05-15 11:56:54 -06005020 /* already have a 2nd entry, fail a third attempt */
Jens Axboe807abcb2020-07-17 17:09:27 -06005021 if (*poll_ptr) {
Jens Axboe18bceab2020-05-15 11:56:54 -06005022 pt->error = -EINVAL;
5023 return;
5024 }
5025 poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
5026 if (!poll) {
5027 pt->error = -ENOMEM;
5028 return;
5029 }
Pavel Begunkov58852d42020-10-16 20:55:56 +01005030 io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
Jens Axboe18bceab2020-05-15 11:56:54 -06005031 refcount_inc(&req->refs);
5032 poll->wait.private = req;
Jens Axboe807abcb2020-07-17 17:09:27 -06005033 *poll_ptr = poll;
Jens Axboe18bceab2020-05-15 11:56:54 -06005034 }
5035
5036 pt->error = 0;
5037 poll->head = head;
Jiufei Xuea31eb4a2020-06-17 17:53:56 +08005038
5039 if (poll->events & EPOLLEXCLUSIVE)
5040 add_wait_queue_exclusive(head, &poll->wait);
5041 else
5042 add_wait_queue(head, &poll->wait);
Jens Axboe18bceab2020-05-15 11:56:54 -06005043}
5044
5045static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
5046 struct poll_table_struct *p)
5047{
5048 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
Jens Axboe807abcb2020-07-17 17:09:27 -06005049 struct async_poll *apoll = pt->req->apoll;
Jens Axboe18bceab2020-05-15 11:56:54 -06005050
Jens Axboe807abcb2020-07-17 17:09:27 -06005051 __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
Jens Axboe18bceab2020-05-15 11:56:54 -06005052}
5053
Jens Axboed7718a92020-02-14 22:23:12 -07005054static void io_async_task_func(struct callback_head *cb)
5055{
5056 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
5057 struct async_poll *apoll = req->apoll;
5058 struct io_ring_ctx *ctx = req->ctx;
5059
5060 trace_io_uring_task_run(req->ctx, req->opcode, req->user_data);
5061
Jens Axboe74ce6ce2020-04-13 11:09:12 -06005062 if (io_poll_rewait(req, &apoll->poll)) {
Jens Axboed7718a92020-02-14 22:23:12 -07005063 spin_unlock_irq(&ctx->completion_lock);
Jens Axboe6d816e02020-08-11 08:04:14 -06005064 percpu_ref_put(&ctx->refs);
Jens Axboe74ce6ce2020-04-13 11:09:12 -06005065 return;
Jens Axboed7718a92020-02-14 22:23:12 -07005066 }
5067
Jens Axboe31067252020-05-17 17:43:31 -06005068 /* If req is still hashed, it cannot have been canceled. Don't check. */
Pavel Begunkov0be0b0e2020-06-30 15:20:42 +03005069 if (hash_hashed(&req->hash_node))
Jens Axboe74ce6ce2020-04-13 11:09:12 -06005070 hash_del(&req->hash_node);
Jens Axboe2bae0472020-04-13 11:16:34 -06005071
Jens Axboed4e7cd32020-08-15 11:44:50 -07005072 io_poll_remove_double(req);
Jens Axboe74ce6ce2020-04-13 11:09:12 -06005073 spin_unlock_irq(&ctx->completion_lock);
5074
Pavel Begunkov0be0b0e2020-06-30 15:20:42 +03005075 if (!READ_ONCE(apoll->poll.canceled))
5076 __io_req_task_submit(req);
5077 else
5078 __io_req_task_cancel(req, -ECANCELED);
Dan Carpenteraa340842020-07-08 21:47:11 +03005079
Jens Axboe6d816e02020-08-11 08:04:14 -06005080 percpu_ref_put(&ctx->refs);
Jens Axboe807abcb2020-07-17 17:09:27 -06005081 kfree(apoll->double_poll);
Jens Axboe31067252020-05-17 17:43:31 -06005082 kfree(apoll);
Jens Axboed7718a92020-02-14 22:23:12 -07005083}
5084
5085static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5086 void *key)
5087{
5088 struct io_kiocb *req = wait->private;
5089 struct io_poll_iocb *poll = &req->apoll->poll;
5090
5091 trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data,
5092 key_to_poll(key));
5093
5094 return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func);
5095}
5096
5097static void io_poll_req_insert(struct io_kiocb *req)
5098{
5099 struct io_ring_ctx *ctx = req->ctx;
5100 struct hlist_head *list;
5101
5102 list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
5103 hlist_add_head(&req->hash_node, list);
5104}
5105
5106static __poll_t __io_arm_poll_handler(struct io_kiocb *req,
5107 struct io_poll_iocb *poll,
5108 struct io_poll_table *ipt, __poll_t mask,
5109 wait_queue_func_t wake_func)
5110 __acquires(&ctx->completion_lock)
5111{
5112 struct io_ring_ctx *ctx = req->ctx;
5113 bool cancel = false;
5114
Pavel Begunkov4d52f332020-10-18 10:17:43 +01005115 INIT_HLIST_NODE(&req->hash_node);
Jens Axboe18bceab2020-05-15 11:56:54 -06005116 io_init_poll_iocb(poll, mask, wake_func);
Pavel Begunkovb90cd192020-06-21 13:09:52 +03005117 poll->file = req->file;
Jens Axboe18bceab2020-05-15 11:56:54 -06005118 poll->wait.private = req;
Jens Axboed7718a92020-02-14 22:23:12 -07005119
5120 ipt->pt._key = mask;
5121 ipt->req = req;
5122 ipt->error = -EINVAL;
5123
Jens Axboed7718a92020-02-14 22:23:12 -07005124 mask = vfs_poll(req->file, &ipt->pt) & poll->events;
5125
5126 spin_lock_irq(&ctx->completion_lock);
5127 if (likely(poll->head)) {
5128 spin_lock(&poll->head->lock);
5129 if (unlikely(list_empty(&poll->wait.entry))) {
5130 if (ipt->error)
5131 cancel = true;
5132 ipt->error = 0;
5133 mask = 0;
5134 }
5135 if (mask || ipt->error)
5136 list_del_init(&poll->wait.entry);
5137 else if (cancel)
5138 WRITE_ONCE(poll->canceled, true);
5139 else if (!poll->done) /* actually waiting for an event */
5140 io_poll_req_insert(req);
5141 spin_unlock(&poll->head->lock);
5142 }
5143
5144 return mask;
5145}
5146
5147static bool io_arm_poll_handler(struct io_kiocb *req)
5148{
5149 const struct io_op_def *def = &io_op_defs[req->opcode];
5150 struct io_ring_ctx *ctx = req->ctx;
5151 struct async_poll *apoll;
5152 struct io_poll_table ipt;
5153 __poll_t mask, ret;
Jens Axboe9dab14b2020-08-25 12:27:50 -06005154 int rw;
Jens Axboed7718a92020-02-14 22:23:12 -07005155
5156 if (!req->file || !file_can_poll(req->file))
5157 return false;
Pavel Begunkov24c74672020-06-21 13:09:51 +03005158 if (req->flags & REQ_F_POLLED)
Jens Axboed7718a92020-02-14 22:23:12 -07005159 return false;
Jens Axboe9dab14b2020-08-25 12:27:50 -06005160 if (def->pollin)
5161 rw = READ;
5162 else if (def->pollout)
5163 rw = WRITE;
5164 else
5165 return false;
5166 /* if we can't nonblock try, then no point in arming a poll handler */
5167 if (!io_file_supports_async(req->file, rw))
Jens Axboed7718a92020-02-14 22:23:12 -07005168 return false;
5169
5170 apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
5171 if (unlikely(!apoll))
5172 return false;
Jens Axboe807abcb2020-07-17 17:09:27 -06005173 apoll->double_poll = NULL;
Jens Axboed7718a92020-02-14 22:23:12 -07005174
5175 req->flags |= REQ_F_POLLED;
Jens Axboed7718a92020-02-14 22:23:12 -07005176 req->apoll = apoll;
Jens Axboed7718a92020-02-14 22:23:12 -07005177
Nathan Chancellor8755d972020-03-02 16:01:19 -07005178 mask = 0;
Jens Axboed7718a92020-02-14 22:23:12 -07005179 if (def->pollin)
Nathan Chancellor8755d972020-03-02 16:01:19 -07005180 mask |= POLLIN | POLLRDNORM;
Jens Axboed7718a92020-02-14 22:23:12 -07005181 if (def->pollout)
5182 mask |= POLLOUT | POLLWRNORM;
Luke Hsiao901341b2020-08-21 21:41:05 -07005183
5184 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5185 if ((req->opcode == IORING_OP_RECVMSG) &&
5186 (req->sr_msg.msg_flags & MSG_ERRQUEUE))
5187 mask &= ~POLLIN;
5188
Jens Axboed7718a92020-02-14 22:23:12 -07005189 mask |= POLLERR | POLLPRI;
5190
5191 ipt.pt._qproc = io_async_queue_proc;
5192
5193 ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask,
5194 io_async_wake);
Jens Axboea36da652020-08-11 09:50:19 -06005195 if (ret || ipt.error) {
Jens Axboed4e7cd32020-08-15 11:44:50 -07005196 io_poll_remove_double(req);
Jens Axboed7718a92020-02-14 22:23:12 -07005197 spin_unlock_irq(&ctx->completion_lock);
Jens Axboe807abcb2020-07-17 17:09:27 -06005198 kfree(apoll->double_poll);
Jens Axboed7718a92020-02-14 22:23:12 -07005199 kfree(apoll);
5200 return false;
5201 }
5202 spin_unlock_irq(&ctx->completion_lock);
5203 trace_io_uring_poll_arm(ctx, req->opcode, req->user_data, mask,
5204 apoll->poll.events);
5205 return true;
5206}
5207
5208static bool __io_poll_remove_one(struct io_kiocb *req,
5209 struct io_poll_iocb *poll)
5210{
Jens Axboeb41e9852020-02-17 09:52:41 -07005211 bool do_complete = false;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005212
5213 spin_lock(&poll->head->lock);
5214 WRITE_ONCE(poll->canceled, true);
Jens Axboe392edb42019-12-09 17:52:20 -07005215 if (!list_empty(&poll->wait.entry)) {
5216 list_del_init(&poll->wait.entry);
Jens Axboeb41e9852020-02-17 09:52:41 -07005217 do_complete = true;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005218 }
5219 spin_unlock(&poll->head->lock);
Jens Axboe3bfa5bc2020-05-17 13:54:12 -06005220 hash_del(&req->hash_node);
Jens Axboed7718a92020-02-14 22:23:12 -07005221 return do_complete;
5222}
5223
5224static bool io_poll_remove_one(struct io_kiocb *req)
5225{
5226 bool do_complete;
5227
Jens Axboed4e7cd32020-08-15 11:44:50 -07005228 io_poll_remove_double(req);
5229
Jens Axboed7718a92020-02-14 22:23:12 -07005230 if (req->opcode == IORING_OP_POLL_ADD) {
5231 do_complete = __io_poll_remove_one(req, &req->poll);
5232 } else {
Jens Axboe3bfa5bc2020-05-17 13:54:12 -06005233 struct async_poll *apoll = req->apoll;
5234
Jens Axboed7718a92020-02-14 22:23:12 -07005235 /* non-poll requests have submit ref still */
Jens Axboe3bfa5bc2020-05-17 13:54:12 -06005236 do_complete = __io_poll_remove_one(req, &apoll->poll);
5237 if (do_complete) {
Jens Axboed7718a92020-02-14 22:23:12 -07005238 io_put_req(req);
Jens Axboe807abcb2020-07-17 17:09:27 -06005239 kfree(apoll->double_poll);
Jens Axboe3bfa5bc2020-05-17 13:54:12 -06005240 kfree(apoll);
5241 }
Xiaoguang Wangb1f573b2020-04-12 14:50:54 +08005242 }
5243
Jens Axboeb41e9852020-02-17 09:52:41 -07005244 if (do_complete) {
5245 io_cqring_fill_event(req, -ECANCELED);
5246 io_commit_cqring(req->ctx);
Jens Axboef254ac02020-08-12 17:33:30 -06005247 req_set_fail_links(req);
Pavel Begunkov216578e2020-10-13 09:44:00 +01005248 io_put_req_deferred(req, 1);
Jens Axboeb41e9852020-02-17 09:52:41 -07005249 }
5250
5251 return do_complete;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005252}
5253
Jens Axboe76e1b642020-09-26 15:05:03 -06005254/*
5255 * Returns true if we found and killed one or more poll requests
5256 */
5257static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk)
Jens Axboe221c5eb2019-01-17 09:41:58 -07005258{
Jens Axboe78076bb2019-12-04 19:56:40 -07005259 struct hlist_node *tmp;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005260 struct io_kiocb *req;
Jens Axboe8e2e1fa2020-04-13 17:05:14 -06005261 int posted = 0, i;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005262
5263 spin_lock_irq(&ctx->completion_lock);
Jens Axboe78076bb2019-12-04 19:56:40 -07005264 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
5265 struct hlist_head *list;
5266
5267 list = &ctx->cancel_hash[i];
Jens Axboef3606e32020-09-22 08:18:24 -06005268 hlist_for_each_entry_safe(req, tmp, list, hash_node) {
5269 if (io_task_match(req, tsk))
5270 posted += io_poll_remove_one(req);
5271 }
Jens Axboe221c5eb2019-01-17 09:41:58 -07005272 }
5273 spin_unlock_irq(&ctx->completion_lock);
Jens Axboeb41e9852020-02-17 09:52:41 -07005274
Jens Axboe8e2e1fa2020-04-13 17:05:14 -06005275 if (posted)
5276 io_cqring_ev_posted(ctx);
Jens Axboe76e1b642020-09-26 15:05:03 -06005277
5278 return posted != 0;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005279}
5280
Jens Axboe47f46762019-11-09 17:43:02 -07005281static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr)
5282{
Jens Axboe78076bb2019-12-04 19:56:40 -07005283 struct hlist_head *list;
Jens Axboe47f46762019-11-09 17:43:02 -07005284 struct io_kiocb *req;
5285
Jens Axboe78076bb2019-12-04 19:56:40 -07005286 list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
5287 hlist_for_each_entry(req, list, hash_node) {
Jens Axboeb41e9852020-02-17 09:52:41 -07005288 if (sqe_addr != req->user_data)
5289 continue;
5290 if (io_poll_remove_one(req))
Jens Axboeeac406c2019-11-14 12:09:58 -07005291 return 0;
Jens Axboeb41e9852020-02-17 09:52:41 -07005292 return -EALREADY;
Jens Axboe47f46762019-11-09 17:43:02 -07005293 }
5294
5295 return -ENOENT;
5296}
5297
Jens Axboe3529d8c2019-12-19 18:24:38 -07005298static int io_poll_remove_prep(struct io_kiocb *req,
5299 const struct io_uring_sqe *sqe)
Jens Axboe221c5eb2019-01-17 09:41:58 -07005300{
Jens Axboe221c5eb2019-01-17 09:41:58 -07005301 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5302 return -EINVAL;
5303 if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
5304 sqe->poll_events)
5305 return -EINVAL;
5306
Jens Axboe0969e782019-12-17 18:40:57 -07005307 req->poll.addr = READ_ONCE(sqe->addr);
Jens Axboe0969e782019-12-17 18:40:57 -07005308 return 0;
5309}
5310
5311/*
5312 * Find a running poll command that matches one specified in sqe->addr,
5313 * and remove it if found.
5314 */
5315static int io_poll_remove(struct io_kiocb *req)
5316{
5317 struct io_ring_ctx *ctx = req->ctx;
5318 u64 addr;
5319 int ret;
5320
Jens Axboe0969e782019-12-17 18:40:57 -07005321 addr = req->poll.addr;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005322 spin_lock_irq(&ctx->completion_lock);
Jens Axboe0969e782019-12-17 18:40:57 -07005323 ret = io_poll_cancel(ctx, addr);
Jens Axboe221c5eb2019-01-17 09:41:58 -07005324 spin_unlock_irq(&ctx->completion_lock);
5325
Jens Axboe4e88d6e2019-12-07 20:59:47 -07005326 if (ret < 0)
5327 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06005328 io_req_complete(req, ret);
Jens Axboe221c5eb2019-01-17 09:41:58 -07005329 return 0;
5330}
5331
Jens Axboe221c5eb2019-01-17 09:41:58 -07005332static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5333 void *key)
5334{
Jens Axboec2f2eb72020-02-10 09:07:05 -07005335 struct io_kiocb *req = wait->private;
5336 struct io_poll_iocb *poll = &req->poll;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005337
Jens Axboed7718a92020-02-14 22:23:12 -07005338 return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func);
Jens Axboe221c5eb2019-01-17 09:41:58 -07005339}
5340
Jens Axboe221c5eb2019-01-17 09:41:58 -07005341static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
5342 struct poll_table_struct *p)
5343{
5344 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
5345
Jens Axboee8c2bc12020-08-15 18:44:09 -07005346 __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
Jens Axboeeac406c2019-11-14 12:09:58 -07005347}
5348
Jens Axboe3529d8c2019-12-19 18:24:38 -07005349static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboe221c5eb2019-01-17 09:41:58 -07005350{
5351 struct io_poll_iocb *poll = &req->poll;
Jiufei Xue5769a352020-06-17 17:53:55 +08005352 u32 events;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005353
5354 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5355 return -EINVAL;
5356 if (sqe->addr || sqe->ioprio || sqe->off || sqe->len || sqe->buf_index)
5357 return -EINVAL;
5358
Jiufei Xue5769a352020-06-17 17:53:55 +08005359 events = READ_ONCE(sqe->poll32_events);
5360#ifdef __BIG_ENDIAN
5361 events = swahw32(events);
5362#endif
Jiufei Xuea31eb4a2020-06-17 17:53:56 +08005363 poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP |
5364 (events & EPOLLEXCLUSIVE);
Jens Axboe0969e782019-12-17 18:40:57 -07005365 return 0;
5366}
5367
Pavel Begunkov014db002020-03-03 21:33:12 +03005368static int io_poll_add(struct io_kiocb *req)
Jens Axboe0969e782019-12-17 18:40:57 -07005369{
5370 struct io_poll_iocb *poll = &req->poll;
5371 struct io_ring_ctx *ctx = req->ctx;
5372 struct io_poll_table ipt;
Jens Axboe0969e782019-12-17 18:40:57 -07005373 __poll_t mask;
Jens Axboe0969e782019-12-17 18:40:57 -07005374
Jens Axboed7718a92020-02-14 22:23:12 -07005375 ipt.pt._qproc = io_poll_queue_proc;
Jens Axboe36703242019-07-25 10:20:18 -06005376
Jens Axboed7718a92020-02-14 22:23:12 -07005377 mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,
5378 io_poll_wake);
Jens Axboe221c5eb2019-01-17 09:41:58 -07005379
Jens Axboe8c838782019-03-12 15:48:16 -06005380 if (mask) { /* no async, we'd stolen it */
Jens Axboe8c838782019-03-12 15:48:16 -06005381 ipt.error = 0;
Jens Axboeb0dd8a42019-11-18 12:14:54 -07005382 io_poll_complete(req, mask, 0);
Jens Axboe8c838782019-03-12 15:48:16 -06005383 }
Jens Axboe221c5eb2019-01-17 09:41:58 -07005384 spin_unlock_irq(&ctx->completion_lock);
5385
Jens Axboe8c838782019-03-12 15:48:16 -06005386 if (mask) {
5387 io_cqring_ev_posted(ctx);
Pavel Begunkov014db002020-03-03 21:33:12 +03005388 io_put_req(req);
Jens Axboe221c5eb2019-01-17 09:41:58 -07005389 }
Jens Axboe8c838782019-03-12 15:48:16 -06005390 return ipt.error;
Jens Axboe221c5eb2019-01-17 09:41:58 -07005391}
5392
Jens Axboe5262f562019-09-17 12:26:57 -06005393static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
5394{
Jens Axboead8a48a2019-11-15 08:49:11 -07005395 struct io_timeout_data *data = container_of(timer,
5396 struct io_timeout_data, timer);
5397 struct io_kiocb *req = data->req;
5398 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe5262f562019-09-17 12:26:57 -06005399 unsigned long flags;
5400
Jens Axboe5262f562019-09-17 12:26:57 -06005401 spin_lock_irqsave(&ctx->completion_lock, flags);
Pavel Begunkova71976f2020-10-10 18:34:11 +01005402 list_del_init(&req->timeout.list);
Pavel Begunkov01cec8c2020-07-30 18:43:50 +03005403 atomic_set(&req->ctx->cq_timeouts,
5404 atomic_read(&req->ctx->cq_timeouts) + 1);
5405
Jens Axboe78e19bb2019-11-06 15:21:34 -07005406 io_cqring_fill_event(req, -ETIME);
Jens Axboe5262f562019-09-17 12:26:57 -06005407 io_commit_cqring(ctx);
5408 spin_unlock_irqrestore(&ctx->completion_lock, flags);
5409
5410 io_cqring_ev_posted(ctx);
Jens Axboe4e88d6e2019-12-07 20:59:47 -07005411 req_set_fail_links(req);
Jens Axboe5262f562019-09-17 12:26:57 -06005412 io_put_req(req);
5413 return HRTIMER_NORESTART;
5414}
5415
Jens Axboef254ac02020-08-12 17:33:30 -06005416static int __io_timeout_cancel(struct io_kiocb *req)
Jens Axboe47f46762019-11-09 17:43:02 -07005417{
Jens Axboee8c2bc12020-08-15 18:44:09 -07005418 struct io_timeout_data *io = req->async_data;
Jens Axboef254ac02020-08-12 17:33:30 -06005419 int ret;
Jens Axboe47f46762019-11-09 17:43:02 -07005420
Jens Axboee8c2bc12020-08-15 18:44:09 -07005421 ret = hrtimer_try_to_cancel(&io->timer);
Jens Axboe47f46762019-11-09 17:43:02 -07005422 if (ret == -1)
5423 return -EALREADY;
Pavel Begunkova71976f2020-10-10 18:34:11 +01005424 list_del_init(&req->timeout.list);
Jens Axboe47f46762019-11-09 17:43:02 -07005425
Jens Axboe4e88d6e2019-12-07 20:59:47 -07005426 req_set_fail_links(req);
Jens Axboe47f46762019-11-09 17:43:02 -07005427 io_cqring_fill_event(req, -ECANCELED);
Pavel Begunkov216578e2020-10-13 09:44:00 +01005428 io_put_req_deferred(req, 1);
Jens Axboe47f46762019-11-09 17:43:02 -07005429 return 0;
5430}
5431
Jens Axboef254ac02020-08-12 17:33:30 -06005432static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
5433{
5434 struct io_kiocb *req;
5435 int ret = -ENOENT;
5436
5437 list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
5438 if (user_data == req->user_data) {
5439 ret = 0;
5440 break;
5441 }
5442 }
5443
5444 if (ret == -ENOENT)
5445 return ret;
5446
5447 return __io_timeout_cancel(req);
5448}
5449
Jens Axboe3529d8c2019-12-19 18:24:38 -07005450static int io_timeout_remove_prep(struct io_kiocb *req,
5451 const struct io_uring_sqe *sqe)
Jens Axboeb29472e2019-12-17 18:50:29 -07005452{
Jens Axboeb29472e2019-12-17 18:50:29 -07005453 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5454 return -EINVAL;
Daniele Albano61710e42020-07-18 14:15:16 -06005455 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5456 return -EINVAL;
Pavel Begunkov0bdf7a22020-10-10 18:34:10 +01005457 if (sqe->ioprio || sqe->buf_index || sqe->len || sqe->timeout_flags)
Jens Axboeb29472e2019-12-17 18:50:29 -07005458 return -EINVAL;
5459
Pavel Begunkov0bdf7a22020-10-10 18:34:10 +01005460 req->timeout_rem.addr = READ_ONCE(sqe->addr);
Jens Axboeb29472e2019-12-17 18:50:29 -07005461 return 0;
5462}
5463
Jens Axboe11365042019-10-16 09:08:32 -06005464/*
5465 * Remove or update an existing timeout command
5466 */
Jens Axboefc4df992019-12-10 14:38:45 -07005467static int io_timeout_remove(struct io_kiocb *req)
Jens Axboe11365042019-10-16 09:08:32 -06005468{
5469 struct io_ring_ctx *ctx = req->ctx;
Jens Axboe47f46762019-11-09 17:43:02 -07005470 int ret;
Jens Axboe11365042019-10-16 09:08:32 -06005471
Jens Axboe11365042019-10-16 09:08:32 -06005472 spin_lock_irq(&ctx->completion_lock);
Pavel Begunkov0bdf7a22020-10-10 18:34:10 +01005473 ret = io_timeout_cancel(ctx, req->timeout_rem.addr);
Jens Axboe11365042019-10-16 09:08:32 -06005474
Jens Axboe47f46762019-11-09 17:43:02 -07005475 io_cqring_fill_event(req, ret);
Jens Axboe11365042019-10-16 09:08:32 -06005476 io_commit_cqring(ctx);
5477 spin_unlock_irq(&ctx->completion_lock);
Jens Axboe5262f562019-09-17 12:26:57 -06005478 io_cqring_ev_posted(ctx);
Jens Axboe4e88d6e2019-12-07 20:59:47 -07005479 if (ret < 0)
5480 req_set_fail_links(req);
Jackie Liuec9c02a2019-11-08 23:50:36 +08005481 io_put_req(req);
Jens Axboe11365042019-10-16 09:08:32 -06005482 return 0;
Jens Axboe5262f562019-09-17 12:26:57 -06005483}
5484
Jens Axboe3529d8c2019-12-19 18:24:38 -07005485static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
Jens Axboe2d283902019-12-04 11:08:05 -07005486 bool is_timeout_link)
Jens Axboe5262f562019-09-17 12:26:57 -06005487{
Jens Axboead8a48a2019-11-15 08:49:11 -07005488 struct io_timeout_data *data;
Jens Axboea41525a2019-10-15 16:48:15 -06005489 unsigned flags;
Pavel Begunkov56080b02020-05-26 20:34:04 +03005490 u32 off = READ_ONCE(sqe->off);
Jens Axboe5262f562019-09-17 12:26:57 -06005491
Jens Axboead8a48a2019-11-15 08:49:11 -07005492 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
Jens Axboe5262f562019-09-17 12:26:57 -06005493 return -EINVAL;
Jens Axboead8a48a2019-11-15 08:49:11 -07005494 if (sqe->ioprio || sqe->buf_index || sqe->len != 1)
Jens Axboea41525a2019-10-15 16:48:15 -06005495 return -EINVAL;
Pavel Begunkov56080b02020-05-26 20:34:04 +03005496 if (off && is_timeout_link)
Jens Axboe2d283902019-12-04 11:08:05 -07005497 return -EINVAL;
Jens Axboea41525a2019-10-15 16:48:15 -06005498 flags = READ_ONCE(sqe->timeout_flags);
5499 if (flags & ~IORING_TIMEOUT_ABS)
Jens Axboe5262f562019-09-17 12:26:57 -06005500 return -EINVAL;
Arnd Bergmannbdf20072019-10-01 09:53:29 -06005501
Pavel Begunkovbfe68a22020-05-30 14:54:18 +03005502 req->timeout.off = off;
Jens Axboe26a61672019-12-20 09:02:01 -07005503
Jens Axboee8c2bc12020-08-15 18:44:09 -07005504 if (!req->async_data && io_alloc_async_data(req))
Jens Axboe26a61672019-12-20 09:02:01 -07005505 return -ENOMEM;
5506
Jens Axboee8c2bc12020-08-15 18:44:09 -07005507 data = req->async_data;
Jens Axboead8a48a2019-11-15 08:49:11 -07005508 data->req = req;
Jens Axboead8a48a2019-11-15 08:49:11 -07005509
5510 if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
Jens Axboe5262f562019-09-17 12:26:57 -06005511 return -EFAULT;
5512
Jens Axboe11365042019-10-16 09:08:32 -06005513 if (flags & IORING_TIMEOUT_ABS)
Jens Axboead8a48a2019-11-15 08:49:11 -07005514 data->mode = HRTIMER_MODE_ABS;
Jens Axboe11365042019-10-16 09:08:32 -06005515 else
Jens Axboead8a48a2019-11-15 08:49:11 -07005516 data->mode = HRTIMER_MODE_REL;
Jens Axboe11365042019-10-16 09:08:32 -06005517
Jens Axboead8a48a2019-11-15 08:49:11 -07005518 hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode);
5519 return 0;
5520}
5521
Jens Axboefc4df992019-12-10 14:38:45 -07005522static int io_timeout(struct io_kiocb *req)
Jens Axboead8a48a2019-11-15 08:49:11 -07005523{
Jens Axboead8a48a2019-11-15 08:49:11 -07005524 struct io_ring_ctx *ctx = req->ctx;
Jens Axboee8c2bc12020-08-15 18:44:09 -07005525 struct io_timeout_data *data = req->async_data;
Jens Axboead8a48a2019-11-15 08:49:11 -07005526 struct list_head *entry;
Pavel Begunkovbfe68a22020-05-30 14:54:18 +03005527 u32 tail, off = req->timeout.off;
Jens Axboead8a48a2019-11-15 08:49:11 -07005528
Pavel Begunkov733f5c92020-05-26 20:34:03 +03005529 spin_lock_irq(&ctx->completion_lock);
Jens Axboe93bd25b2019-11-11 23:34:31 -07005530
Jens Axboe5262f562019-09-17 12:26:57 -06005531 /*
5532 * sqe->off holds how many events that need to occur for this
Jens Axboe93bd25b2019-11-11 23:34:31 -07005533 * timeout event to be satisfied. If it isn't set, then this is
5534 * a pure timeout request, sequence isn't used.
Jens Axboe5262f562019-09-17 12:26:57 -06005535 */
Pavel Begunkov8eb7e2d2020-06-29 13:13:02 +03005536 if (io_is_timeout_noseq(req)) {
Jens Axboe93bd25b2019-11-11 23:34:31 -07005537 entry = ctx->timeout_list.prev;
5538 goto add;
5539 }
Jens Axboe5262f562019-09-17 12:26:57 -06005540
Pavel Begunkovbfe68a22020-05-30 14:54:18 +03005541 tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
5542 req->timeout.target_seq = tail + off;
Jens Axboe5262f562019-09-17 12:26:57 -06005543
5544 /*
5545 * Insertion sort, ensuring the first entry in the list is always
5546 * the one we need first.
5547 */
Jens Axboe5262f562019-09-17 12:26:57 -06005548 list_for_each_prev(entry, &ctx->timeout_list) {
Pavel Begunkov135fcde2020-07-13 23:37:12 +03005549 struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
5550 timeout.list);
Jens Axboe5262f562019-09-17 12:26:57 -06005551
Pavel Begunkov8eb7e2d2020-06-29 13:13:02 +03005552 if (io_is_timeout_noseq(nxt))
Jens Axboe93bd25b2019-11-11 23:34:31 -07005553 continue;
Pavel Begunkovbfe68a22020-05-30 14:54:18 +03005554 /* nxt.seq is behind @tail, otherwise would've been completed */
5555 if (off >= nxt->timeout.target_seq - tail)
Jens Axboe5262f562019-09-17 12:26:57 -06005556 break;
5557 }
Jens Axboe93bd25b2019-11-11 23:34:31 -07005558add:
Pavel Begunkov135fcde2020-07-13 23:37:12 +03005559 list_add(&req->timeout.list, entry);
Jens Axboead8a48a2019-11-15 08:49:11 -07005560 data->timer.function = io_timeout_fn;
5561 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
Jens Axboe842f9612019-10-29 12:34:10 -06005562 spin_unlock_irq(&ctx->completion_lock);
Jens Axboe5262f562019-09-17 12:26:57 -06005563 return 0;
5564}
5565
Jens Axboe62755e32019-10-28 21:49:21 -06005566static bool io_cancel_cb(struct io_wq_work *work, void *data)
Jens Axboede0617e2019-04-06 21:51:27 -06005567{
Jens Axboe62755e32019-10-28 21:49:21 -06005568 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
Jens Axboede0617e2019-04-06 21:51:27 -06005569
Jens Axboe62755e32019-10-28 21:49:21 -06005570 return req->user_data == (unsigned long) data;
5571}
5572
Jens Axboee977d6d2019-11-05 12:39:45 -07005573static int io_async_cancel_one(struct io_ring_ctx *ctx, void *sqe_addr)
Jens Axboe62755e32019-10-28 21:49:21 -06005574{
Jens Axboe62755e32019-10-28 21:49:21 -06005575 enum io_wq_cancel cancel_ret;
Jens Axboe62755e32019-10-28 21:49:21 -06005576 int ret = 0;
5577
Pavel Begunkov4f26bda2020-06-15 10:24:03 +03005578 cancel_ret = io_wq_cancel_cb(ctx->io_wq, io_cancel_cb, sqe_addr, false);
Jens Axboe62755e32019-10-28 21:49:21 -06005579 switch (cancel_ret) {
5580 case IO_WQ_CANCEL_OK:
5581 ret = 0;
5582 break;
5583 case IO_WQ_CANCEL_RUNNING:
5584 ret = -EALREADY;
5585 break;
5586 case IO_WQ_CANCEL_NOTFOUND:
5587 ret = -ENOENT;
5588 break;
5589 }
5590
Jens Axboee977d6d2019-11-05 12:39:45 -07005591 return ret;
5592}
5593
Jens Axboe47f46762019-11-09 17:43:02 -07005594static void io_async_find_and_cancel(struct io_ring_ctx *ctx,
5595 struct io_kiocb *req, __u64 sqe_addr,
Pavel Begunkov014db002020-03-03 21:33:12 +03005596 int success_ret)
Jens Axboe47f46762019-11-09 17:43:02 -07005597{
5598 unsigned long flags;
5599 int ret;
5600
5601 ret = io_async_cancel_one(ctx, (void *) (unsigned long) sqe_addr);
5602 if (ret != -ENOENT) {
5603 spin_lock_irqsave(&ctx->completion_lock, flags);
5604 goto done;
5605 }
5606
5607 spin_lock_irqsave(&ctx->completion_lock, flags);
5608 ret = io_timeout_cancel(ctx, sqe_addr);
5609 if (ret != -ENOENT)
5610 goto done;
5611 ret = io_poll_cancel(ctx, sqe_addr);
5612done:
Jens Axboeb0dd8a42019-11-18 12:14:54 -07005613 if (!ret)
5614 ret = success_ret;
Jens Axboe47f46762019-11-09 17:43:02 -07005615 io_cqring_fill_event(req, ret);
5616 io_commit_cqring(ctx);
5617 spin_unlock_irqrestore(&ctx->completion_lock, flags);
5618 io_cqring_ev_posted(ctx);
5619
Jens Axboe4e88d6e2019-12-07 20:59:47 -07005620 if (ret < 0)
5621 req_set_fail_links(req);
Pavel Begunkov014db002020-03-03 21:33:12 +03005622 io_put_req(req);
Jens Axboe47f46762019-11-09 17:43:02 -07005623}
5624
Jens Axboe3529d8c2019-12-19 18:24:38 -07005625static int io_async_cancel_prep(struct io_kiocb *req,
5626 const struct io_uring_sqe *sqe)
Jens Axboee977d6d2019-11-05 12:39:45 -07005627{
Jens Axboefbf23842019-12-17 18:45:56 -07005628 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
Jens Axboee977d6d2019-11-05 12:39:45 -07005629 return -EINVAL;
Daniele Albano61710e42020-07-18 14:15:16 -06005630 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5631 return -EINVAL;
5632 if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags)
Jens Axboee977d6d2019-11-05 12:39:45 -07005633 return -EINVAL;
5634
Jens Axboefbf23842019-12-17 18:45:56 -07005635 req->cancel.addr = READ_ONCE(sqe->addr);
5636 return 0;
5637}
5638
Pavel Begunkov014db002020-03-03 21:33:12 +03005639static int io_async_cancel(struct io_kiocb *req)
Jens Axboefbf23842019-12-17 18:45:56 -07005640{
5641 struct io_ring_ctx *ctx = req->ctx;
Jens Axboefbf23842019-12-17 18:45:56 -07005642
Pavel Begunkov014db002020-03-03 21:33:12 +03005643 io_async_find_and_cancel(ctx, req, req->cancel.addr, 0);
Jens Axboe62755e32019-10-28 21:49:21 -06005644 return 0;
5645}
5646
Jens Axboe05f3fb32019-12-09 11:22:50 -07005647static int io_files_update_prep(struct io_kiocb *req,
5648 const struct io_uring_sqe *sqe)
5649{
Jens Axboe6ca56f82020-09-18 16:51:19 -06005650 if (unlikely(req->ctx->flags & IORING_SETUP_SQPOLL))
5651 return -EINVAL;
Daniele Albano61710e42020-07-18 14:15:16 -06005652 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5653 return -EINVAL;
5654 if (sqe->ioprio || sqe->rw_flags)
Jens Axboe05f3fb32019-12-09 11:22:50 -07005655 return -EINVAL;
5656
5657 req->files_update.offset = READ_ONCE(sqe->off);
5658 req->files_update.nr_args = READ_ONCE(sqe->len);
5659 if (!req->files_update.nr_args)
5660 return -EINVAL;
5661 req->files_update.arg = READ_ONCE(sqe->addr);
5662 return 0;
5663}
5664
Jens Axboe229a7b62020-06-22 10:13:11 -06005665static int io_files_update(struct io_kiocb *req, bool force_nonblock,
5666 struct io_comp_state *cs)
Jens Axboe05f3fb32019-12-09 11:22:50 -07005667{
5668 struct io_ring_ctx *ctx = req->ctx;
5669 struct io_uring_files_update up;
5670 int ret;
5671
Jens Axboef86cd202020-01-29 13:46:44 -07005672 if (force_nonblock)
Jens Axboe05f3fb32019-12-09 11:22:50 -07005673 return -EAGAIN;
Jens Axboe05f3fb32019-12-09 11:22:50 -07005674
5675 up.offset = req->files_update.offset;
5676 up.fds = req->files_update.arg;
5677
5678 mutex_lock(&ctx->uring_lock);
5679 ret = __io_sqe_files_update(ctx, &up, req->files_update.nr_args);
5680 mutex_unlock(&ctx->uring_lock);
5681
5682 if (ret < 0)
5683 req_set_fail_links(req);
Jens Axboe229a7b62020-06-22 10:13:11 -06005684 __io_req_complete(req, ret, 0, cs);
Jens Axboe05f3fb32019-12-09 11:22:50 -07005685 return 0;
5686}
5687
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005688static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboef67676d2019-12-02 11:03:47 -07005689{
Jens Axboed625c6e2019-12-17 19:53:05 -07005690 switch (req->opcode) {
Jens Axboee7815732019-12-17 19:45:06 -07005691 case IORING_OP_NOP:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005692 return 0;
Jens Axboef67676d2019-12-02 11:03:47 -07005693 case IORING_OP_READV:
5694 case IORING_OP_READ_FIXED:
Jens Axboe3a6820f2019-12-22 15:19:35 -07005695 case IORING_OP_READ:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005696 return io_read_prep(req, sqe);
Jens Axboef67676d2019-12-02 11:03:47 -07005697 case IORING_OP_WRITEV:
5698 case IORING_OP_WRITE_FIXED:
Jens Axboe3a6820f2019-12-22 15:19:35 -07005699 case IORING_OP_WRITE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005700 return io_write_prep(req, sqe);
Jens Axboe0969e782019-12-17 18:40:57 -07005701 case IORING_OP_POLL_ADD:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005702 return io_poll_add_prep(req, sqe);
Jens Axboe0969e782019-12-17 18:40:57 -07005703 case IORING_OP_POLL_REMOVE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005704 return io_poll_remove_prep(req, sqe);
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07005705 case IORING_OP_FSYNC:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005706 return io_prep_fsync(req, sqe);
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07005707 case IORING_OP_SYNC_FILE_RANGE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005708 return io_prep_sfr(req, sqe);
Jens Axboe03b12302019-12-02 18:50:25 -07005709 case IORING_OP_SENDMSG:
Jens Axboefddafac2020-01-04 20:19:44 -07005710 case IORING_OP_SEND:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005711 return io_sendmsg_prep(req, sqe);
Jens Axboe03b12302019-12-02 18:50:25 -07005712 case IORING_OP_RECVMSG:
Jens Axboefddafac2020-01-04 20:19:44 -07005713 case IORING_OP_RECV:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005714 return io_recvmsg_prep(req, sqe);
Jens Axboef499a022019-12-02 16:28:46 -07005715 case IORING_OP_CONNECT:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005716 return io_connect_prep(req, sqe);
Jens Axboe2d283902019-12-04 11:08:05 -07005717 case IORING_OP_TIMEOUT:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005718 return io_timeout_prep(req, sqe, false);
Jens Axboeb29472e2019-12-17 18:50:29 -07005719 case IORING_OP_TIMEOUT_REMOVE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005720 return io_timeout_remove_prep(req, sqe);
Jens Axboefbf23842019-12-17 18:45:56 -07005721 case IORING_OP_ASYNC_CANCEL:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005722 return io_async_cancel_prep(req, sqe);
Jens Axboe2d283902019-12-04 11:08:05 -07005723 case IORING_OP_LINK_TIMEOUT:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005724 return io_timeout_prep(req, sqe, true);
Jens Axboe8ed8d3c2019-12-16 11:55:28 -07005725 case IORING_OP_ACCEPT:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005726 return io_accept_prep(req, sqe);
Jens Axboed63d1b52019-12-10 10:38:56 -07005727 case IORING_OP_FALLOCATE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005728 return io_fallocate_prep(req, sqe);
Jens Axboe15b71ab2019-12-11 11:20:36 -07005729 case IORING_OP_OPENAT:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005730 return io_openat_prep(req, sqe);
Jens Axboeb5dba592019-12-11 14:02:38 -07005731 case IORING_OP_CLOSE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005732 return io_close_prep(req, sqe);
Jens Axboe05f3fb32019-12-09 11:22:50 -07005733 case IORING_OP_FILES_UPDATE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005734 return io_files_update_prep(req, sqe);
Jens Axboeeddc7ef2019-12-13 21:18:10 -07005735 case IORING_OP_STATX:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005736 return io_statx_prep(req, sqe);
Jens Axboe4840e412019-12-25 22:03:45 -07005737 case IORING_OP_FADVISE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005738 return io_fadvise_prep(req, sqe);
Jens Axboec1ca7572019-12-25 22:18:28 -07005739 case IORING_OP_MADVISE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005740 return io_madvise_prep(req, sqe);
Jens Axboecebdb982020-01-08 17:59:24 -07005741 case IORING_OP_OPENAT2:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005742 return io_openat2_prep(req, sqe);
Jens Axboe3e4827b2020-01-08 15:18:09 -07005743 case IORING_OP_EPOLL_CTL:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005744 return io_epoll_ctl_prep(req, sqe);
Pavel Begunkov7d67af22020-02-24 11:32:45 +03005745 case IORING_OP_SPLICE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005746 return io_splice_prep(req, sqe);
Jens Axboeddf0322d2020-02-23 16:41:33 -07005747 case IORING_OP_PROVIDE_BUFFERS:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005748 return io_provide_buffers_prep(req, sqe);
Jens Axboe067524e2020-03-02 16:32:28 -07005749 case IORING_OP_REMOVE_BUFFERS:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005750 return io_remove_buffers_prep(req, sqe);
Pavel Begunkovf2a8d5c2020-05-17 14:18:06 +03005751 case IORING_OP_TEE:
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005752 return io_tee_prep(req, sqe);
Jens Axboef67676d2019-12-02 11:03:47 -07005753 }
5754
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005755 printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
5756 req->opcode);
5757 return-EINVAL;
5758}
5759
Jens Axboedef596e2019-01-09 08:59:42 -07005760static int io_req_defer_prep(struct io_kiocb *req,
5761 const struct io_uring_sqe *sqe)
Jens Axboedef596e2019-01-09 08:59:42 -07005762{
Jens Axboedef596e2019-01-09 08:59:42 -07005763 if (!sqe)
Jens Axboe2b188cc2019-01-07 10:46:33 -07005764 return 0;
Jens Axboee8c2bc12020-08-15 18:44:09 -07005765 if (io_alloc_async_data(req))
Jens Axboeb76da702019-11-20 13:05:32 -07005766 return -EAGAIN;
Pavel Begunkovbfe76552020-09-30 22:57:55 +03005767 return io_req_prep(req, sqe);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005768}
5769
Pavel Begunkov9cf7c102020-07-13 23:37:15 +03005770static u32 io_get_sequence(struct io_kiocb *req)
5771{
5772 struct io_kiocb *pos;
5773 struct io_ring_ctx *ctx = req->ctx;
5774 u32 total_submitted, nr_reqs = 1;
5775
5776 if (req->flags & REQ_F_LINK_HEAD)
5777 list_for_each_entry(pos, &req->link_list, link_list)
5778 nr_reqs++;
5779
5780 total_submitted = ctx->cached_sq_head - ctx->cached_sq_dropped;
5781 return total_submitted - nr_reqs;
5782}
5783
Jens Axboe3529d8c2019-12-19 18:24:38 -07005784static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe)
Jens Axboe2b188cc2019-01-07 10:46:33 -07005785{
5786 struct io_ring_ctx *ctx = req->ctx;
Pavel Begunkov27dc8332020-07-13 23:37:14 +03005787 struct io_defer_entry *de;
Jens Axboe2b188cc2019-01-07 10:46:33 -07005788 int ret;
Pavel Begunkov9cf7c102020-07-13 23:37:15 +03005789 u32 seq;
Jens Axboe2b188cc2019-01-07 10:46:33 -07005790
5791 /* Still need defer if there is pending req in defer list. */
Pavel Begunkov9cf7c102020-07-13 23:37:15 +03005792 if (likely(list_empty_careful(&ctx->defer_list) &&
5793 !(req->flags & REQ_F_IO_DRAIN)))
5794 return 0;
5795
5796 seq = io_get_sequence(req);
5797 /* Still a chance to pass the sequence check */
5798 if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
Jens Axboe2b188cc2019-01-07 10:46:33 -07005799 return 0;
5800
Jens Axboee8c2bc12020-08-15 18:44:09 -07005801 if (!req->async_data) {
Pavel Begunkov650b5482020-05-17 14:02:11 +03005802 ret = io_req_defer_prep(req, sqe);
Pavel Begunkov327d6d92020-07-15 12:46:51 +03005803 if (ret)
Pavel Begunkov650b5482020-05-17 14:02:11 +03005804 return ret;
5805 }
Pavel Begunkovcbdcb432020-06-29 19:18:43 +03005806 io_prep_async_link(req);
Pavel Begunkov27dc8332020-07-13 23:37:14 +03005807 de = kmalloc(sizeof(*de), GFP_KERNEL);
5808 if (!de)
5809 return -ENOMEM;
Jens Axboe31b51512019-01-18 22:56:34 -07005810
5811 spin_lock_irq(&ctx->completion_lock);
Pavel Begunkov9cf7c102020-07-13 23:37:15 +03005812 if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
Jens Axboe31b51512019-01-18 22:56:34 -07005813 spin_unlock_irq(&ctx->completion_lock);
Pavel Begunkov27dc8332020-07-13 23:37:14 +03005814 kfree(de);
Pavel Begunkovae348172020-07-23 20:25:20 +03005815 io_queue_async_work(req);
5816 return -EIOCBQUEUED;
Jens Axboe31b51512019-01-18 22:56:34 -07005817 }
5818
5819 trace_io_uring_defer(ctx, req, req->user_data);
Pavel Begunkov27dc8332020-07-13 23:37:14 +03005820 de->req = req;
Pavel Begunkov9cf7c102020-07-13 23:37:15 +03005821 de->seq = seq;
Pavel Begunkov27dc8332020-07-13 23:37:14 +03005822 list_add_tail(&de->list, &ctx->defer_list);
Jens Axboe31b51512019-01-18 22:56:34 -07005823 spin_unlock_irq(&ctx->completion_lock);
5824 return -EIOCBQUEUED;
5825}
Jens Axboeedafcce2019-01-09 09:16:05 -07005826
Jens Axboef573d382020-09-22 10:19:24 -06005827static void io_req_drop_files(struct io_kiocb *req)
5828{
5829 struct io_ring_ctx *ctx = req->ctx;
5830 unsigned long flags;
5831
5832 spin_lock_irqsave(&ctx->inflight_lock, flags);
5833 list_del(&req->inflight_entry);
5834 if (waitqueue_active(&ctx->inflight_wait))
5835 wake_up(&ctx->inflight_wait);
5836 spin_unlock_irqrestore(&ctx->inflight_lock, flags);
5837 req->flags &= ~REQ_F_INFLIGHT;
Jens Axboe98447d62020-10-14 10:48:51 -06005838 put_files_struct(req->work.identity->files);
5839 put_nsproxy(req->work.identity->nsproxy);
Jens Axboedfead8a2020-10-14 10:12:37 -06005840 req->work.flags &= ~IO_WQ_WORK_FILES;
Jens Axboef573d382020-09-22 10:19:24 -06005841}
5842
Pavel Begunkov3ca405e2020-07-13 23:37:08 +03005843static void __io_clean_op(struct io_kiocb *req)
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03005844{
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005845 if (req->flags & REQ_F_BUFFER_SELECTED) {
5846 switch (req->opcode) {
5847 case IORING_OP_READV:
5848 case IORING_OP_READ_FIXED:
5849 case IORING_OP_READ:
Jens Axboebcda7ba2020-02-23 16:42:51 -07005850 kfree((void *)(unsigned long)req->rw.addr);
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005851 break;
5852 case IORING_OP_RECVMSG:
5853 case IORING_OP_RECV:
Jens Axboe52de1fe2020-02-27 10:15:42 -07005854 kfree(req->sr_msg.kbuf);
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005855 break;
5856 }
5857 req->flags &= ~REQ_F_BUFFER_SELECTED;
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03005858 }
5859
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005860 if (req->flags & REQ_F_NEED_CLEANUP) {
5861 switch (req->opcode) {
5862 case IORING_OP_READV:
5863 case IORING_OP_READ_FIXED:
5864 case IORING_OP_READ:
5865 case IORING_OP_WRITEV:
5866 case IORING_OP_WRITE_FIXED:
Jens Axboee8c2bc12020-08-15 18:44:09 -07005867 case IORING_OP_WRITE: {
5868 struct io_async_rw *io = req->async_data;
5869 if (io->free_iovec)
5870 kfree(io->free_iovec);
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005871 break;
Jens Axboee8c2bc12020-08-15 18:44:09 -07005872 }
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005873 case IORING_OP_RECVMSG:
Jens Axboee8c2bc12020-08-15 18:44:09 -07005874 case IORING_OP_SENDMSG: {
5875 struct io_async_msghdr *io = req->async_data;
5876 if (io->iov != io->fast_iov)
5877 kfree(io->iov);
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005878 break;
Jens Axboee8c2bc12020-08-15 18:44:09 -07005879 }
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005880 case IORING_OP_SPLICE:
5881 case IORING_OP_TEE:
5882 io_put_file(req, req->splice.file_in,
5883 (req->splice.flags & SPLICE_F_FD_IN_FIXED));
5884 break;
Jens Axboef3cd48502020-09-24 14:55:54 -06005885 case IORING_OP_OPENAT:
5886 case IORING_OP_OPENAT2:
5887 if (req->open.filename)
5888 putname(req->open.filename);
5889 break;
Pavel Begunkov0e1b6fe32020-07-16 23:28:02 +03005890 }
5891 req->flags &= ~REQ_F_NEED_CLEANUP;
5892 }
Pavel Begunkovbb175342020-08-20 11:33:35 +03005893
Jens Axboef573d382020-09-22 10:19:24 -06005894 if (req->flags & REQ_F_INFLIGHT)
5895 io_req_drop_files(req);
Pavel Begunkov99bc4c32020-02-07 22:04:45 +03005896}
5897
Pavel Begunkovc1379e22020-09-30 22:57:56 +03005898static int io_issue_sqe(struct io_kiocb *req, bool force_nonblock,
5899 struct io_comp_state *cs)
Jens Axboeedafcce2019-01-09 09:16:05 -07005900{
Jens Axboeedafcce2019-01-09 09:16:05 -07005901 struct io_ring_ctx *ctx = req->ctx;
Jens Axboed625c6e2019-12-17 19:53:05 -07005902 int ret;
Jens Axboeedafcce2019-01-09 09:16:05 -07005903
Jens Axboed625c6e2019-12-17 19:53:05 -07005904 switch (req->opcode) {
Jens Axboe2b188cc2019-01-07 10:46:33 -07005905 case IORING_OP_NOP:
Jens Axboe229a7b62020-06-22 10:13:11 -06005906 ret = io_nop(req, cs);
Jens Axboe31b51512019-01-18 22:56:34 -07005907 break;
5908 case IORING_OP_READV:
Jens Axboe3529d8c2019-12-19 18:24:38 -07005909 case IORING_OP_READ_FIXED:
Jens Axboe3a6820f2019-12-22 15:19:35 -07005910 case IORING_OP_READ:
Jens Axboea1d7c392020-06-22 11:09:46 -06005911 ret = io_read(req, force_nonblock, cs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005912 break;
5913 case IORING_OP_WRITEV:
Jens Axboe2b188cc2019-01-07 10:46:33 -07005914 case IORING_OP_WRITE_FIXED:
Jens Axboe3a6820f2019-12-22 15:19:35 -07005915 case IORING_OP_WRITE:
Jens Axboea1d7c392020-06-22 11:09:46 -06005916 ret = io_write(req, force_nonblock, cs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005917 break;
5918 case IORING_OP_FSYNC:
Pavel Begunkov014db002020-03-03 21:33:12 +03005919 ret = io_fsync(req, force_nonblock);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005920 break;
5921 case IORING_OP_POLL_ADD:
Pavel Begunkov014db002020-03-03 21:33:12 +03005922 ret = io_poll_add(req);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005923 break;
5924 case IORING_OP_POLL_REMOVE:
Jens Axboeb76da702019-11-20 13:05:32 -07005925 ret = io_poll_remove(req);
5926 break;
5927 case IORING_OP_SYNC_FILE_RANGE:
Pavel Begunkov014db002020-03-03 21:33:12 +03005928 ret = io_sync_file_range(req, force_nonblock);
Jens Axboeb76da702019-11-20 13:05:32 -07005929 break;
5930 case IORING_OP_SENDMSG:
Pavel Begunkov062d04d2020-10-10 18:34:12 +01005931 ret = io_sendmsg(req, force_nonblock, cs);
5932 break;
Jens Axboefddafac2020-01-04 20:19:44 -07005933 case IORING_OP_SEND:
Pavel Begunkov062d04d2020-10-10 18:34:12 +01005934 ret = io_send(req, force_nonblock, cs);
Jens Axboeb76da702019-11-20 13:05:32 -07005935 break;
5936 case IORING_OP_RECVMSG:
Pavel Begunkov062d04d2020-10-10 18:34:12 +01005937 ret = io_recvmsg(req, force_nonblock, cs);
5938 break;
Jens Axboefddafac2020-01-04 20:19:44 -07005939 case IORING_OP_RECV:
Pavel Begunkov062d04d2020-10-10 18:34:12 +01005940 ret = io_recv(req, force_nonblock, cs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005941 break;
5942 case IORING_OP_TIMEOUT:
5943 ret = io_timeout(req);
5944 break;
5945 case IORING_OP_TIMEOUT_REMOVE:
5946 ret = io_timeout_remove(req);
5947 break;
5948 case IORING_OP_ACCEPT:
Jens Axboe229a7b62020-06-22 10:13:11 -06005949 ret = io_accept(req, force_nonblock, cs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005950 break;
5951 case IORING_OP_CONNECT:
Jens Axboe229a7b62020-06-22 10:13:11 -06005952 ret = io_connect(req, force_nonblock, cs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005953 break;
5954 case IORING_OP_ASYNC_CANCEL:
Pavel Begunkov014db002020-03-03 21:33:12 +03005955 ret = io_async_cancel(req);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005956 break;
Jens Axboed63d1b52019-12-10 10:38:56 -07005957 case IORING_OP_FALLOCATE:
Pavel Begunkov014db002020-03-03 21:33:12 +03005958 ret = io_fallocate(req, force_nonblock);
Jens Axboed63d1b52019-12-10 10:38:56 -07005959 break;
Jens Axboe15b71ab2019-12-11 11:20:36 -07005960 case IORING_OP_OPENAT:
Pavel Begunkov014db002020-03-03 21:33:12 +03005961 ret = io_openat(req, force_nonblock);
Jens Axboe15b71ab2019-12-11 11:20:36 -07005962 break;
Jens Axboeb5dba592019-12-11 14:02:38 -07005963 case IORING_OP_CLOSE:
Jens Axboe229a7b62020-06-22 10:13:11 -06005964 ret = io_close(req, force_nonblock, cs);
Jens Axboeb5dba592019-12-11 14:02:38 -07005965 break;
Jens Axboe05f3fb32019-12-09 11:22:50 -07005966 case IORING_OP_FILES_UPDATE:
Jens Axboe229a7b62020-06-22 10:13:11 -06005967 ret = io_files_update(req, force_nonblock, cs);
Jens Axboe05f3fb32019-12-09 11:22:50 -07005968 break;
Jens Axboeeddc7ef2019-12-13 21:18:10 -07005969 case IORING_OP_STATX:
Pavel Begunkov014db002020-03-03 21:33:12 +03005970 ret = io_statx(req, force_nonblock);
Jens Axboeeddc7ef2019-12-13 21:18:10 -07005971 break;
Jens Axboe4840e412019-12-25 22:03:45 -07005972 case IORING_OP_FADVISE:
Pavel Begunkov014db002020-03-03 21:33:12 +03005973 ret = io_fadvise(req, force_nonblock);
Jens Axboe4840e412019-12-25 22:03:45 -07005974 break;
Jens Axboec1ca7572019-12-25 22:18:28 -07005975 case IORING_OP_MADVISE:
Pavel Begunkov014db002020-03-03 21:33:12 +03005976 ret = io_madvise(req, force_nonblock);
Jens Axboec1ca7572019-12-25 22:18:28 -07005977 break;
Jens Axboecebdb982020-01-08 17:59:24 -07005978 case IORING_OP_OPENAT2:
Pavel Begunkov014db002020-03-03 21:33:12 +03005979 ret = io_openat2(req, force_nonblock);
Jens Axboecebdb982020-01-08 17:59:24 -07005980 break;
Jens Axboe3e4827b2020-01-08 15:18:09 -07005981 case IORING_OP_EPOLL_CTL:
Jens Axboe229a7b62020-06-22 10:13:11 -06005982 ret = io_epoll_ctl(req, force_nonblock, cs);
Jens Axboe3e4827b2020-01-08 15:18:09 -07005983 break;
Pavel Begunkov7d67af22020-02-24 11:32:45 +03005984 case IORING_OP_SPLICE:
Pavel Begunkov014db002020-03-03 21:33:12 +03005985 ret = io_splice(req, force_nonblock);
Pavel Begunkov7d67af22020-02-24 11:32:45 +03005986 break;
Jens Axboeddf0322d2020-02-23 16:41:33 -07005987 case IORING_OP_PROVIDE_BUFFERS:
Jens Axboe229a7b62020-06-22 10:13:11 -06005988 ret = io_provide_buffers(req, force_nonblock, cs);
Jens Axboeddf0322d2020-02-23 16:41:33 -07005989 break;
Jens Axboe067524e2020-03-02 16:32:28 -07005990 case IORING_OP_REMOVE_BUFFERS:
Jens Axboe229a7b62020-06-22 10:13:11 -06005991 ret = io_remove_buffers(req, force_nonblock, cs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07005992 break;
Pavel Begunkovf2a8d5c2020-05-17 14:18:06 +03005993 case IORING_OP_TEE:
Pavel Begunkovf2a8d5c2020-05-17 14:18:06 +03005994 ret = io_tee(req, force_nonblock);
5995 break;
Jens Axboe2b188cc2019-01-07 10:46:33 -07005996 default:
5997 ret = -EINVAL;
5998 break;
Jens Axboe31b51512019-01-18 22:56:34 -07005999 }
6000
6001 if (ret)
Jens Axboeedafcce2019-01-09 09:16:05 -07006002 return ret;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006003
Jens Axboeb5325762020-05-19 21:20:27 -06006004 /* If the op doesn't have a file, we're not polling for it */
6005 if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file) {
Jens Axboe11ba8202020-01-15 21:51:17 -07006006 const bool in_async = io_wq_current_is_worker();
6007
Jens Axboe11ba8202020-01-15 21:51:17 -07006008 /* workqueue context doesn't hold uring_lock, grab it now */
6009 if (in_async)
6010 mutex_lock(&ctx->uring_lock);
6011
Jens Axboe2b188cc2019-01-07 10:46:33 -07006012 io_iopoll_req_issued(req);
Jens Axboe11ba8202020-01-15 21:51:17 -07006013
6014 if (in_async)
6015 mutex_unlock(&ctx->uring_lock);
Jens Axboe2b188cc2019-01-07 10:46:33 -07006016 }
6017
6018 return 0;
6019}
6020
Pavel Begunkovf4db7182020-06-25 18:20:54 +03006021static struct io_wq_work *io_wq_submit_work(struct io_wq_work *work)
Pavel Begunkovd4c81f32020-06-08 21:08:19 +03006022{
Jens Axboe2b188cc2019-01-07 10:46:33 -07006023 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
Pavel Begunkov6df1db62020-07-03 22:15:06 +03006024 struct io_kiocb *timeout;
Jens Axboe561fb042019-10-24 07:25:42 -06006025 int ret = 0;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006026
Pavel Begunkov6df1db62020-07-03 22:15:06 +03006027 timeout = io_prep_linked_timeout(req);
6028 if (timeout)
6029 io_queue_linked_timeout(timeout);
Pavel Begunkovd4c81f32020-06-08 21:08:19 +03006030
Jens Axboe0c9d5cc2019-12-11 19:29:43 -07006031 /* if NO_CANCEL is set, we must still run the work */
6032 if ((work->flags & (IO_WQ_WORK_CANCEL|IO_WQ_WORK_NO_CANCEL)) ==
6033 IO_WQ_WORK_CANCEL) {
Jens Axboe561fb042019-10-24 07:25:42 -06006034 ret = -ECANCELED;
Jens Axboe0c9d5cc2019-12-11 19:29:43 -07006035 }
Jens Axboe31b51512019-01-18 22:56:34 -07006036
Jens Axboe561fb042019-10-24 07:25:42 -06006037 if (!ret) {
Jens Axboe561fb042019-10-24 07:25:42 -06006038 do {
Pavel Begunkovc1379e22020-09-30 22:57:56 +03006039 ret = io_issue_sqe(req, false, NULL);
Jens Axboe561fb042019-10-24 07:25:42 -06006040 /*
6041 * We can get EAGAIN for polled IO even though we're
6042 * forcing a sync submission from here, since we can't
6043 * wait for request slots on the block side.
6044 */
6045 if (ret != -EAGAIN)
6046 break;
6047 cond_resched();
6048 } while (1);
6049 }
Jens Axboe31b51512019-01-18 22:56:34 -07006050
Jens Axboe561fb042019-10-24 07:25:42 -06006051 if (ret) {
Jens Axboe4e88d6e2019-12-07 20:59:47 -07006052 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06006053 io_req_complete(req, ret);
Jens Axboeedafcce2019-01-09 09:16:05 -07006054 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07006055
Pavel Begunkovf4db7182020-06-25 18:20:54 +03006056 return io_steal_work(req);
Jens Axboe31b51512019-01-18 22:56:34 -07006057}
Jens Axboe2b188cc2019-01-07 10:46:33 -07006058
Jens Axboe65e19f52019-10-26 07:20:21 -06006059static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
6060 int index)
Jens Axboe09bb8392019-03-13 12:39:28 -06006061{
Jens Axboe65e19f52019-10-26 07:20:21 -06006062 struct fixed_file_table *table;
6063
Jens Axboe05f3fb32019-12-09 11:22:50 -07006064 table = &ctx->file_data->table[index >> IORING_FILE_TABLE_SHIFT];
Xiaoming Ni84695082020-05-11 19:25:43 +08006065 return table->files[index & IORING_FILE_TABLE_MASK];
Jens Axboe65e19f52019-10-26 07:20:21 -06006066}
6067
Pavel Begunkov8371adf2020-10-10 18:34:08 +01006068static struct file *io_file_get(struct io_submit_state *state,
6069 struct io_kiocb *req, int fd, bool fixed)
Pavel Begunkov8da11c12020-02-24 11:32:44 +03006070{
6071 struct io_ring_ctx *ctx = req->ctx;
6072 struct file *file;
6073
6074 if (fixed) {
Pavel Begunkov479f5172020-10-10 18:34:07 +01006075 if (unlikely((unsigned int)fd >= ctx->nr_user_files))
Pavel Begunkov8371adf2020-10-10 18:34:08 +01006076 return NULL;
Pavel Begunkov8da11c12020-02-24 11:32:44 +03006077 fd = array_index_nospec(fd, ctx->nr_user_files);
6078 file = io_file_from_index(ctx, fd);
Jens Axboefd2206e2020-06-02 16:40:47 -06006079 if (file) {
Pavel Begunkovb2e96852020-10-10 18:34:16 +01006080 req->fixed_file_refs = &ctx->file_data->node->refs;
Jens Axboefd2206e2020-06-02 16:40:47 -06006081 percpu_ref_get(req->fixed_file_refs);
6082 }
Pavel Begunkov8da11c12020-02-24 11:32:44 +03006083 } else {
6084 trace_io_uring_file_get(ctx, fd);
6085 file = __io_file_get(state, fd);
Pavel Begunkov8da11c12020-02-24 11:32:44 +03006086 }
6087
Pavel Begunkov8371adf2020-10-10 18:34:08 +01006088 return file;
Pavel Begunkov8da11c12020-02-24 11:32:44 +03006089}
6090
Jens Axboe3529d8c2019-12-19 18:24:38 -07006091static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req,
Jens Axboe63ff8222020-05-07 14:56:15 -06006092 int fd)
Jens Axboe09bb8392019-03-13 12:39:28 -06006093{
Pavel Begunkov8da11c12020-02-24 11:32:44 +03006094 bool fixed;
Jens Axboe09bb8392019-03-13 12:39:28 -06006095
Jens Axboe63ff8222020-05-07 14:56:15 -06006096 fixed = (req->flags & REQ_F_FIXED_FILE) != 0;
Pavel Begunkov0cdaf762020-05-17 14:13:40 +03006097 if (unlikely(!fixed && io_async_submit(req->ctx)))
Pavel Begunkov8da11c12020-02-24 11:32:44 +03006098 return -EBADF;
Jens Axboe09bb8392019-03-13 12:39:28 -06006099
Pavel Begunkov8371adf2020-10-10 18:34:08 +01006100 req->file = io_file_get(state, req, fd, fixed);
6101 if (req->file || io_op_defs[req->opcode].needs_file_no_error)
Jens Axboef86cd202020-01-29 13:46:44 -07006102 return 0;
Pavel Begunkov8371adf2020-10-10 18:34:08 +01006103 return -EBADF;
Pavel Begunkovf56040b2020-07-23 20:25:21 +03006104}
6105
Jens Axboe2665abf2019-11-05 12:40:47 -07006106static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
6107{
Jens Axboead8a48a2019-11-15 08:49:11 -07006108 struct io_timeout_data *data = container_of(timer,
6109 struct io_timeout_data, timer);
6110 struct io_kiocb *req = data->req;
Jens Axboe2665abf2019-11-05 12:40:47 -07006111 struct io_ring_ctx *ctx = req->ctx;
6112 struct io_kiocb *prev = NULL;
6113 unsigned long flags;
Jens Axboe2665abf2019-11-05 12:40:47 -07006114
6115 spin_lock_irqsave(&ctx->completion_lock, flags);
6116
6117 /*
6118 * We don't expect the list to be empty, that will only happen if we
6119 * race with the completion of the linked work.
6120 */
Pavel Begunkov44932332019-12-05 16:16:35 +03006121 if (!list_empty(&req->link_list)) {
6122 prev = list_entry(req->link_list.prev, struct io_kiocb,
6123 link_list);
Pavel Begunkov900fad42020-10-19 16:39:16 +01006124 if (refcount_inc_not_zero(&prev->refs))
Pavel Begunkov44932332019-12-05 16:16:35 +03006125 list_del_init(&req->link_list);
Pavel Begunkov900fad42020-10-19 16:39:16 +01006126 else
Jens Axboe76a46e02019-11-10 23:34:16 -07006127 prev = NULL;
Jens Axboe2665abf2019-11-05 12:40:47 -07006128 }
6129
6130 spin_unlock_irqrestore(&ctx->completion_lock, flags);
6131
6132 if (prev) {
Jens Axboe4e88d6e2019-12-07 20:59:47 -07006133 req_set_fail_links(prev);
Pavel Begunkov014db002020-03-03 21:33:12 +03006134 io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME);
Jens Axboe76a46e02019-11-10 23:34:16 -07006135 io_put_req(prev);
Jens Axboe47f46762019-11-09 17:43:02 -07006136 } else {
Jens Axboee1e16092020-06-22 09:17:17 -06006137 io_req_complete(req, -ETIME);
Jens Axboe2665abf2019-11-05 12:40:47 -07006138 }
Jens Axboe2665abf2019-11-05 12:40:47 -07006139 return HRTIMER_NORESTART;
6140}
6141
Jens Axboe7271ef32020-08-10 09:55:22 -06006142static void __io_queue_linked_timeout(struct io_kiocb *req)
Jens Axboe2665abf2019-11-05 12:40:47 -07006143{
Jens Axboe76a46e02019-11-10 23:34:16 -07006144 /*
6145 * If the list is now empty, then our linked request finished before
6146 * we got a chance to setup the timer
6147 */
Pavel Begunkov44932332019-12-05 16:16:35 +03006148 if (!list_empty(&req->link_list)) {
Jens Axboee8c2bc12020-08-15 18:44:09 -07006149 struct io_timeout_data *data = req->async_data;
Jens Axboe94ae5e72019-11-14 19:39:52 -07006150
Jens Axboead8a48a2019-11-15 08:49:11 -07006151 data->timer.function = io_link_timeout_fn;
6152 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
6153 data->mode);
Jens Axboe2665abf2019-11-05 12:40:47 -07006154 }
Jens Axboe7271ef32020-08-10 09:55:22 -06006155}
6156
6157static void io_queue_linked_timeout(struct io_kiocb *req)
6158{
6159 struct io_ring_ctx *ctx = req->ctx;
6160
6161 spin_lock_irq(&ctx->completion_lock);
6162 __io_queue_linked_timeout(req);
Jens Axboe76a46e02019-11-10 23:34:16 -07006163 spin_unlock_irq(&ctx->completion_lock);
Jens Axboe2665abf2019-11-05 12:40:47 -07006164
Jens Axboe2665abf2019-11-05 12:40:47 -07006165 /* drop submission reference */
Jens Axboe76a46e02019-11-10 23:34:16 -07006166 io_put_req(req);
Jens Axboe2665abf2019-11-05 12:40:47 -07006167}
6168
Jens Axboead8a48a2019-11-15 08:49:11 -07006169static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
Jens Axboe2665abf2019-11-05 12:40:47 -07006170{
6171 struct io_kiocb *nxt;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006172
Pavel Begunkovdea3b492020-04-12 02:05:04 +03006173 if (!(req->flags & REQ_F_LINK_HEAD))
Jens Axboe2665abf2019-11-05 12:40:47 -07006174 return NULL;
Pavel Begunkov6df1db62020-07-03 22:15:06 +03006175 if (req->flags & REQ_F_LINK_TIMEOUT)
Jens Axboed7718a92020-02-14 22:23:12 -07006176 return NULL;
Jens Axboe2665abf2019-11-05 12:40:47 -07006177
Pavel Begunkov44932332019-12-05 16:16:35 +03006178 nxt = list_first_entry_or_null(&req->link_list, struct io_kiocb,
6179 link_list);
Jens Axboed625c6e2019-12-17 19:53:05 -07006180 if (!nxt || nxt->opcode != IORING_OP_LINK_TIMEOUT)
Jens Axboe76a46e02019-11-10 23:34:16 -07006181 return NULL;
Jens Axboe2665abf2019-11-05 12:40:47 -07006182
Pavel Begunkov900fad42020-10-19 16:39:16 +01006183 nxt->flags |= REQ_F_LTIMEOUT_ACTIVE;
Jens Axboe76a46e02019-11-10 23:34:16 -07006184 req->flags |= REQ_F_LINK_TIMEOUT;
Jens Axboe76a46e02019-11-10 23:34:16 -07006185 return nxt;
Jens Axboe2665abf2019-11-05 12:40:47 -07006186}
6187
Pavel Begunkovc1379e22020-09-30 22:57:56 +03006188static void __io_queue_sqe(struct io_kiocb *req, struct io_comp_state *cs)
Jens Axboe2b188cc2019-01-07 10:46:33 -07006189{
Jens Axboe4a0a7a12019-12-09 20:01:01 -07006190 struct io_kiocb *linked_timeout;
Jens Axboe193155c2020-02-22 23:22:19 -07006191 const struct cred *old_creds = NULL;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006192 int ret;
6193
Jens Axboe4a0a7a12019-12-09 20:01:01 -07006194again:
6195 linked_timeout = io_prep_linked_timeout(req);
6196
Pavel Begunkov2e5aa6c2020-10-18 10:17:37 +01006197 if ((req->flags & REQ_F_WORK_INITIALIZED) &&
6198 (req->work.flags & IO_WQ_WORK_CREDS) &&
Jens Axboe98447d62020-10-14 10:48:51 -06006199 req->work.identity->creds != current_cred()) {
Jens Axboe193155c2020-02-22 23:22:19 -07006200 if (old_creds)
6201 revert_creds(old_creds);
Jens Axboe98447d62020-10-14 10:48:51 -06006202 if (old_creds == req->work.identity->creds)
Jens Axboe193155c2020-02-22 23:22:19 -07006203 old_creds = NULL; /* restored original creds */
6204 else
Jens Axboe98447d62020-10-14 10:48:51 -06006205 old_creds = override_creds(req->work.identity->creds);
Jens Axboe193155c2020-02-22 23:22:19 -07006206 }
6207
Pavel Begunkovc1379e22020-09-30 22:57:56 +03006208 ret = io_issue_sqe(req, true, cs);
Jens Axboe491381ce2019-10-17 09:20:46 -06006209
6210 /*
6211 * We async punt it if the file wasn't marked NOWAIT, or if the file
6212 * doesn't support non-blocking read/write attempts
6213 */
Pavel Begunkov24c74672020-06-21 13:09:51 +03006214 if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
Pavel Begunkovf063c542020-07-25 14:41:59 +03006215 if (!io_arm_poll_handler(req)) {
Pavel Begunkovf063c542020-07-25 14:41:59 +03006216 /*
6217 * Queued up for async execution, worker will release
6218 * submit reference when the iocb is actually submitted.
6219 */
6220 io_queue_async_work(req);
Jens Axboe2b188cc2019-01-07 10:46:33 -07006221 }
Pavel Begunkovbbad27b2019-11-19 23:32:47 +03006222
Pavel Begunkovf063c542020-07-25 14:41:59 +03006223 if (linked_timeout)
6224 io_queue_linked_timeout(linked_timeout);
Pavel Begunkov0d63c142020-10-22 16:47:18 +01006225 } else if (likely(!ret)) {
6226 /* drop submission reference */
6227 req = io_put_req_find_next(req);
6228 if (linked_timeout)
6229 io_queue_linked_timeout(linked_timeout);
Jens Axboee65ef562019-03-12 10:16:44 -06006230
Pavel Begunkov0d63c142020-10-22 16:47:18 +01006231 if (req) {
6232 if (!(req->flags & REQ_F_FORCE_ASYNC))
6233 goto again;
6234 io_queue_async_work(req);
6235 }
6236 } else {
Pavel Begunkov652532a2020-07-03 22:15:07 +03006237 /* un-prep timeout, so it'll be killed as any other linked */
6238 req->flags &= ~REQ_F_LINK_TIMEOUT;
Jens Axboe4e88d6e2019-12-07 20:59:47 -07006239 req_set_fail_links(req);
Jens Axboee65ef562019-03-12 10:16:44 -06006240 io_put_req(req);
Pavel Begunkov652532a2020-07-03 22:15:07 +03006241 io_req_complete(req, ret);
Jens Axboe9e645e112019-05-10 16:07:28 -06006242 }
Pavel Begunkov652532a2020-07-03 22:15:07 +03006243
Jens Axboe193155c2020-02-22 23:22:19 -07006244 if (old_creds)
6245 revert_creds(old_creds);
Jens Axboe2b188cc2019-01-07 10:46:33 -07006246}
6247
Jens Axboef13fad72020-06-22 09:34:30 -06006248static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
6249 struct io_comp_state *cs)
Jackie Liu4fe2c962019-09-09 20:50:40 +08006250{
6251 int ret;
6252
Jens Axboe3529d8c2019-12-19 18:24:38 -07006253 ret = io_req_defer(req, sqe);
Jackie Liu4fe2c962019-09-09 20:50:40 +08006254 if (ret) {
6255 if (ret != -EIOCBQUEUED) {
Pavel Begunkov11185912020-01-22 23:09:35 +03006256fail_req:
Jens Axboe4e88d6e2019-12-07 20:59:47 -07006257 req_set_fail_links(req);
Jens Axboee1e16092020-06-22 09:17:17 -06006258 io_put_req(req);
6259 io_req_complete(req, ret);
Jackie Liu4fe2c962019-09-09 20:50:40 +08006260 }
Pavel Begunkov25508782019-12-30 21:24:47 +03006261 } else if (req->flags & REQ_F_FORCE_ASYNC) {
Jens Axboee8c2bc12020-08-15 18:44:09 -07006262 if (!req->async_data) {
Pavel Begunkovbd2ab182020-05-17 14:02:12 +03006263 ret = io_req_defer_prep(req, sqe);
Pavel Begunkov327d6d92020-07-15 12:46:51 +03006264 if (unlikely(ret))
Pavel Begunkovbd2ab182020-05-17 14:02:12 +03006265 goto fail_req;
6266 }
Jens Axboece35a472019-12-17 08:04:44 -07006267 io_queue_async_work(req);
6268 } else {
Pavel Begunkovc1379e22020-09-30 22:57:56 +03006269 if (sqe) {
6270 ret = io_req_prep(req, sqe);
6271 if (unlikely(ret))
6272 goto fail_req;
6273 }
6274 __io_queue_sqe(req, cs);
Jens Axboece35a472019-12-17 08:04:44 -07006275 }
Jackie Liu4fe2c962019-09-09 20:50:40 +08006276}
6277
Jens Axboef13fad72020-06-22 09:34:30 -06006278static inline void io_queue_link_head(struct io_kiocb *req,
6279 struct io_comp_state *cs)
Jackie Liu4fe2c962019-09-09 20:50:40 +08006280{
Jens Axboe94ae5e72019-11-14 19:39:52 -07006281 if (unlikely(req->flags & REQ_F_FAIL_LINK)) {
Jens Axboee1e16092020-06-22 09:17:17 -06006282 io_put_req(req);
6283 io_req_complete(req, -ECANCELED);
Pavel Begunkov1b4a51b2019-11-21 11:54:28 +03006284 } else
Jens Axboef13fad72020-06-22 09:34:30 -06006285 io_queue_sqe(req, NULL, cs);
Jackie Liu4fe2c962019-09-09 20:50:40 +08006286}
6287
Pavel Begunkov1d4240c2020-04-12 02:05:03 +03006288static int io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe,
Jens Axboef13fad72020-06-22 09:34:30 -06006289 struct io_kiocb **link, struct io_comp_state *cs)
Jens Axboe9e645e112019-05-10 16:07:28 -06006290{
Jackie Liua197f662019-11-08 08:09:12 -07006291 struct io_ring_ctx *ctx = req->ctx;
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006292 int ret;
Jens Axboe9e645e112019-05-10 16:07:28 -06006293
Jens Axboe9e645e112019-05-10 16:07:28 -06006294 /*
6295 * If we already have a head request, queue this one for async
6296 * submittal once the head completes. If we don't have a head but
6297 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6298 * submitted sync once the chain is complete. If none of those
6299 * conditions are true (normal request), then just queue it.
6300 */
6301 if (*link) {
Pavel Begunkov9d763772019-12-17 02:22:07 +03006302 struct io_kiocb *head = *link;
Jens Axboe9e645e112019-05-10 16:07:28 -06006303
Pavel Begunkov8cdf2192020-01-25 00:40:24 +03006304 /*
6305 * Taking sequential execution of a link, draining both sides
6306 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6307 * requests in the link. So, it drains the head and the
6308 * next after the link request. The last one is done via
6309 * drain_next flag to persist the effect across calls.
6310 */
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006311 if (req->flags & REQ_F_IO_DRAIN) {
Pavel Begunkov711be032020-01-17 03:57:59 +03006312 head->flags |= REQ_F_IO_DRAIN;
6313 ctx->drain_next = 1;
6314 }
Jens Axboe3529d8c2019-12-19 18:24:38 -07006315 ret = io_req_defer_prep(req, sqe);
Pavel Begunkov327d6d92020-07-15 12:46:51 +03006316 if (unlikely(ret)) {
Jens Axboe4e88d6e2019-12-07 20:59:47 -07006317 /* fail even hard links since we don't submit */
Pavel Begunkov9d763772019-12-17 02:22:07 +03006318 head->flags |= REQ_F_FAIL_LINK;
Pavel Begunkov1d4240c2020-04-12 02:05:03 +03006319 return ret;
Jens Axboe2d283902019-12-04 11:08:05 -07006320 }
Pavel Begunkov9d763772019-12-17 02:22:07 +03006321 trace_io_uring_link(ctx, req, head);
6322 list_add_tail(&req->link_list, &head->link_list);
Jens Axboe9e645e112019-05-10 16:07:28 -06006323
Pavel Begunkov32fe5252019-12-17 22:26:58 +03006324 /* last request of a link, enqueue the link */
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006325 if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
Jens Axboef13fad72020-06-22 09:34:30 -06006326 io_queue_link_head(head, cs);
Pavel Begunkov32fe5252019-12-17 22:26:58 +03006327 *link = NULL;
6328 }
Jens Axboe9e645e112019-05-10 16:07:28 -06006329 } else {
Pavel Begunkov711be032020-01-17 03:57:59 +03006330 if (unlikely(ctx->drain_next)) {
6331 req->flags |= REQ_F_IO_DRAIN;
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006332 ctx->drain_next = 0;
Pavel Begunkov711be032020-01-17 03:57:59 +03006333 }
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006334 if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
Pavel Begunkovdea3b492020-04-12 02:05:04 +03006335 req->flags |= REQ_F_LINK_HEAD;
Pavel Begunkov711be032020-01-17 03:57:59 +03006336 INIT_LIST_HEAD(&req->link_list);
Pavel Begunkovf1d96a82020-03-13 22:29:14 +03006337
Pavel Begunkov711be032020-01-17 03:57:59 +03006338 ret = io_req_defer_prep(req, sqe);
Pavel Begunkov327d6d92020-07-15 12:46:51 +03006339 if (unlikely(ret))
Pavel Begunkov711be032020-01-17 03:57:59 +03006340 req->flags |= REQ_F_FAIL_LINK;
6341 *link = req;
6342 } else {
Jens Axboef13fad72020-06-22 09:34:30 -06006343 io_queue_sqe(req, sqe, cs);
Pavel Begunkov711be032020-01-17 03:57:59 +03006344 }
Jens Axboe9e645e112019-05-10 16:07:28 -06006345 }
Pavel Begunkov2e6e1fd2019-12-05 16:15:45 +03006346
Pavel Begunkov1d4240c2020-04-12 02:05:03 +03006347 return 0;
Jens Axboe9e645e112019-05-10 16:07:28 -06006348}
6349
Jens Axboe9a56a232019-01-09 09:06:50 -07006350/*
6351 * Batched submission is done, ensure local IO is flushed out.
6352 */
6353static void io_submit_state_end(struct io_submit_state *state)
6354{
Jens Axboef13fad72020-06-22 09:34:30 -06006355 if (!list_empty(&state->comp.list))
6356 io_submit_flush_completions(&state->comp);
Jens Axboe9a56a232019-01-09 09:06:50 -07006357 blk_finish_plug(&state->plug);
Pavel Begunkov9f13c352020-05-17 14:13:41 +03006358 io_state_file_put(state);
Jens Axboe2579f912019-01-09 09:10:43 -07006359 if (state->free_reqs)
Pavel Begunkov6c8a3132020-02-01 03:58:00 +03006360 kmem_cache_free_bulk(req_cachep, state->free_reqs, state->reqs);
Jens Axboe9a56a232019-01-09 09:06:50 -07006361}
6362
6363/*
6364 * Start submission side cache.
6365 */
6366static void io_submit_state_start(struct io_submit_state *state,
Jens Axboe013538b2020-06-22 09:29:15 -06006367 struct io_ring_ctx *ctx, unsigned int max_ios)
Jens Axboe9a56a232019-01-09 09:06:50 -07006368{
6369 blk_start_plug(&state->plug);
Jens Axboe013538b2020-06-22 09:29:15 -06006370 state->comp.nr = 0;
6371 INIT_LIST_HEAD(&state->comp.list);
6372 state->comp.ctx = ctx;
Jens Axboe2579f912019-01-09 09:10:43 -07006373 state->free_reqs = 0;
Jens Axboe9a56a232019-01-09 09:06:50 -07006374 state->file = NULL;
6375 state->ios_left = max_ios;
6376}
6377
Jens Axboe2b188cc2019-01-07 10:46:33 -07006378static void io_commit_sqring(struct io_ring_ctx *ctx)
6379{
Hristo Venev75b28af2019-08-26 17:23:46 +00006380 struct io_rings *rings = ctx->rings;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006381
Pavel Begunkovcaf582c2019-12-30 21:24:46 +03006382 /*
6383 * Ensure any loads from the SQEs are done at this point,
6384 * since once we write the new head, the application could
6385 * write new data to them.
6386 */
6387 smp_store_release(&rings->sq.head, ctx->cached_sq_head);
Jens Axboe2b188cc2019-01-07 10:46:33 -07006388}
6389
6390/*
Jens Axboe3529d8c2019-12-19 18:24:38 -07006391 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
Jens Axboe2b188cc2019-01-07 10:46:33 -07006392 * that is mapped by userspace. This means that care needs to be taken to
6393 * ensure that reads are stable, as we cannot rely on userspace always
6394 * being a good citizen. If members of the sqe are validated and then later
6395 * used, it's important that those reads are done through READ_ONCE() to
6396 * prevent a re-load down the line.
6397 */
Pavel Begunkov709b3022020-04-08 08:58:43 +03006398static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
Jens Axboe2b188cc2019-01-07 10:46:33 -07006399{
Hristo Venev75b28af2019-08-26 17:23:46 +00006400 u32 *sq_array = ctx->sq_array;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006401 unsigned head;
6402
6403 /*
6404 * The cached sq head (or cq tail) serves two purposes:
6405 *
6406 * 1) allows us to batch the cost of updating the user visible
6407 * head updates.
6408 * 2) allows the kernel side to track the head on its own, even
6409 * though the application is the one updating it.
6410 */
Pavel Begunkovee7d46d2019-12-30 21:24:45 +03006411 head = READ_ONCE(sq_array[ctx->cached_sq_head & ctx->sq_mask]);
Pavel Begunkov709b3022020-04-08 08:58:43 +03006412 if (likely(head < ctx->sq_entries))
6413 return &ctx->sq_sqes[head];
Jens Axboe2b188cc2019-01-07 10:46:33 -07006414
6415 /* drop invalid entries */
Jens Axboe498ccd92019-10-25 10:04:25 -06006416 ctx->cached_sq_dropped++;
Pavel Begunkovee7d46d2019-12-30 21:24:45 +03006417 WRITE_ONCE(ctx->rings->sq_dropped, ctx->cached_sq_dropped);
Pavel Begunkov709b3022020-04-08 08:58:43 +03006418 return NULL;
6419}
6420
6421static inline void io_consume_sqe(struct io_ring_ctx *ctx)
6422{
6423 ctx->cached_sq_head++;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006424}
6425
Stefano Garzarella21b55db2020-08-27 16:58:30 +02006426/*
6427 * Check SQE restrictions (opcode and flags).
6428 *
6429 * Returns 'true' if SQE is allowed, 'false' otherwise.
6430 */
6431static inline bool io_check_restriction(struct io_ring_ctx *ctx,
6432 struct io_kiocb *req,
6433 unsigned int sqe_flags)
6434{
6435 if (!ctx->restricted)
6436 return true;
6437
6438 if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
6439 return false;
6440
6441 if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
6442 ctx->restrictions.sqe_flags_required)
6443 return false;
6444
6445 if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
6446 ctx->restrictions.sqe_flags_required))
6447 return false;
6448
6449 return true;
6450}
6451
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006452#define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6453 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6454 IOSQE_BUFFER_SELECT)
6455
6456static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
6457 const struct io_uring_sqe *sqe,
Pavel Begunkov0cdaf762020-05-17 14:13:40 +03006458 struct io_submit_state *state)
Pavel Begunkov0553b8b2020-04-08 08:58:45 +03006459{
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006460 unsigned int sqe_flags;
Pavel Begunkov71b547c2020-10-10 18:34:09 +01006461 int id, ret;
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006462
Pavel Begunkov0553b8b2020-04-08 08:58:45 +03006463 req->opcode = READ_ONCE(sqe->opcode);
6464 req->user_data = READ_ONCE(sqe->user_data);
Jens Axboee8c2bc12020-08-15 18:44:09 -07006465 req->async_data = NULL;
Pavel Begunkov0553b8b2020-04-08 08:58:45 +03006466 req->file = NULL;
6467 req->ctx = ctx;
6468 req->flags = 0;
6469 /* one is dropped after submission, the other at completion */
6470 refcount_set(&req->refs, 2);
Pavel Begunkov4dd28242020-06-15 10:33:13 +03006471 req->task = current;
Pavel Begunkov0553b8b2020-04-08 08:58:45 +03006472 req->result = 0;
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006473
6474 if (unlikely(req->opcode >= IORING_OP_LAST))
6475 return -EINVAL;
6476
Jens Axboe9d8426a2020-06-16 18:42:49 -06006477 if (unlikely(io_sq_thread_acquire_mm(ctx, req)))
6478 return -EFAULT;
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006479
6480 sqe_flags = READ_ONCE(sqe->flags);
6481 /* enforce forwards compatibility on users */
6482 if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))
6483 return -EINVAL;
6484
Stefano Garzarella21b55db2020-08-27 16:58:30 +02006485 if (unlikely(!io_check_restriction(ctx, req, sqe_flags)))
6486 return -EACCES;
6487
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006488 if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
6489 !io_op_defs[req->opcode].buffer_select)
6490 return -EOPNOTSUPP;
6491
6492 id = READ_ONCE(sqe->personality);
6493 if (id) {
Jens Axboe1e6fa522020-10-15 08:46:24 -06006494 struct io_identity *iod;
6495
Jens Axboe1e6fa522020-10-15 08:46:24 -06006496 iod = idr_find(&ctx->personality_idr, id);
6497 if (unlikely(!iod))
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006498 return -EINVAL;
Jens Axboe1e6fa522020-10-15 08:46:24 -06006499 refcount_inc(&iod->count);
Pavel Begunkovec99ca62020-10-18 10:17:38 +01006500
6501 __io_req_init_async(req);
Jens Axboe1e6fa522020-10-15 08:46:24 -06006502 get_cred(iod->creds);
6503 req->work.identity = iod;
Jens Axboedfead8a2020-10-14 10:12:37 -06006504 req->work.flags |= IO_WQ_WORK_CREDS;
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006505 }
6506
6507 /* same numerical values with corresponding REQ_F_*, safe to copy */
Pavel Begunkovc11368a52020-05-17 14:13:42 +03006508 req->flags |= sqe_flags;
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006509
Jens Axboe63ff8222020-05-07 14:56:15 -06006510 if (!io_op_defs[req->opcode].needs_file)
6511 return 0;
6512
Pavel Begunkov71b547c2020-10-10 18:34:09 +01006513 ret = io_req_set_file(state, req, READ_ONCE(sqe->fd));
6514 state->ios_left--;
6515 return ret;
Pavel Begunkov0553b8b2020-04-08 08:58:45 +03006516}
6517
Jens Axboe0f212202020-09-13 13:09:39 -06006518static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
Jens Axboe6c271ce2019-01-10 11:22:30 -07006519{
Jens Axboeac8691c2020-06-01 08:30:41 -06006520 struct io_submit_state state;
Jens Axboe9e645e112019-05-10 16:07:28 -06006521 struct io_kiocb *link = NULL;
Jens Axboe9e645e112019-05-10 16:07:28 -06006522 int i, submitted = 0;
Jens Axboe6c271ce2019-01-10 11:22:30 -07006523
Jens Axboec4a2ed72019-11-21 21:01:26 -07006524 /* if we have a backlog and couldn't flush it all, return BUSY */
Jens Axboead3eb2c2019-12-18 17:12:20 -07006525 if (test_bit(0, &ctx->sq_check_overflow)) {
6526 if (!list_empty(&ctx->cq_overflow_list) &&
Jens Axboee6c8aa92020-09-28 13:10:13 -06006527 !io_cqring_overflow_flush(ctx, false, NULL, NULL))
Jens Axboead3eb2c2019-12-18 17:12:20 -07006528 return -EBUSY;
6529 }
Jens Axboe6c271ce2019-01-10 11:22:30 -07006530
Pavel Begunkovee7d46d2019-12-30 21:24:45 +03006531 /* make sure SQ entry isn't read before tail */
6532 nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
Pavel Begunkov9ef4f122019-12-30 21:24:44 +03006533
Pavel Begunkov2b85edf2019-12-28 14:13:03 +03006534 if (!percpu_ref_tryget_many(&ctx->refs, nr))
6535 return -EAGAIN;
Jens Axboe6c271ce2019-01-10 11:22:30 -07006536
Jens Axboed8a6df12020-10-15 16:24:45 -06006537 percpu_counter_add(&current->io_uring->inflight, nr);
Jens Axboefaf7b512020-10-07 12:48:53 -06006538 refcount_add(nr, &current->usage);
Jens Axboe6c271ce2019-01-10 11:22:30 -07006539
Jens Axboe6c271ce2019-01-10 11:22:30 -07006540 io_submit_state_start(&state, ctx, nr);
Pavel Begunkovb14cca02020-01-17 04:45:59 +03006541
Jens Axboe6c271ce2019-01-10 11:22:30 -07006542 for (i = 0; i < nr; i++) {
Jens Axboe3529d8c2019-12-19 18:24:38 -07006543 const struct io_uring_sqe *sqe;
Pavel Begunkov196be952019-11-07 01:41:06 +03006544 struct io_kiocb *req;
Pavel Begunkov1cb1edb2020-02-06 21:16:09 +03006545 int err;
Pavel Begunkovfb5ccc92019-10-25 12:31:30 +03006546
Pavel Begunkovb1e50e52020-04-08 08:58:44 +03006547 sqe = io_get_sqe(ctx);
6548 if (unlikely(!sqe)) {
6549 io_consume_sqe(ctx);
6550 break;
6551 }
Jens Axboeac8691c2020-06-01 08:30:41 -06006552 req = io_alloc_req(ctx, &state);
Pavel Begunkov196be952019-11-07 01:41:06 +03006553 if (unlikely(!req)) {
6554 if (!submitted)
6555 submitted = -EAGAIN;
Pavel Begunkovfb5ccc92019-10-25 12:31:30 +03006556 break;
Jens Axboe9e645e112019-05-10 16:07:28 -06006557 }
Pavel Begunkov709b3022020-04-08 08:58:43 +03006558 io_consume_sqe(ctx);
Jens Axboed3656342019-12-18 09:50:26 -07006559 /* will complete beyond this point, count as submitted */
6560 submitted++;
6561
Pavel Begunkov692d8362020-10-10 18:34:13 +01006562 err = io_init_req(ctx, req, sqe, &state);
Pavel Begunkovef4ff582020-04-12 02:05:05 +03006563 if (unlikely(err)) {
Pavel Begunkov1cb1edb2020-02-06 21:16:09 +03006564fail_req:
Jens Axboee1e16092020-06-22 09:17:17 -06006565 io_put_req(req);
6566 io_req_complete(req, err);
Jens Axboed3656342019-12-18 09:50:26 -07006567 break;
6568 }
6569
Jens Axboe354420f2020-01-08 18:55:15 -07006570 trace_io_uring_submit_sqe(ctx, req->opcode, req->user_data,
Pavel Begunkov0cdaf762020-05-17 14:13:40 +03006571 true, io_async_submit(ctx));
Jens Axboef13fad72020-06-22 09:34:30 -06006572 err = io_submit_sqe(req, sqe, &link, &state.comp);
Pavel Begunkov1d4240c2020-04-12 02:05:03 +03006573 if (err)
6574 goto fail_req;
Jens Axboe6c271ce2019-01-10 11:22:30 -07006575 }
6576
Pavel Begunkov9466f432020-01-25 22:34:01 +03006577 if (unlikely(submitted != nr)) {
6578 int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
Jens Axboed8a6df12020-10-15 16:24:45 -06006579 struct io_uring_task *tctx = current->io_uring;
6580 int unused = nr - ref_used;
Pavel Begunkov9466f432020-01-25 22:34:01 +03006581
Jens Axboed8a6df12020-10-15 16:24:45 -06006582 percpu_ref_put_many(&ctx->refs, unused);
6583 percpu_counter_sub(&tctx->inflight, unused);
6584 put_task_struct_many(current, unused);
Pavel Begunkov9466f432020-01-25 22:34:01 +03006585 }
Jens Axboe9e645e112019-05-10 16:07:28 -06006586 if (link)
Jens Axboef13fad72020-06-22 09:34:30 -06006587 io_queue_link_head(link, &state.comp);
Jens Axboeac8691c2020-06-01 08:30:41 -06006588 io_submit_state_end(&state);
Jens Axboe6c271ce2019-01-10 11:22:30 -07006589
Pavel Begunkovae9428c2019-11-06 00:22:14 +03006590 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6591 io_commit_sqring(ctx);
6592
Jens Axboe6c271ce2019-01-10 11:22:30 -07006593 return submitted;
6594}
6595
Xiaoguang Wang23b36282020-07-23 20:57:24 +08006596static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
6597{
6598 /* Tell userspace we may need a wakeup call */
6599 spin_lock_irq(&ctx->completion_lock);
6600 ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP;
6601 spin_unlock_irq(&ctx->completion_lock);
6602}
6603
6604static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
6605{
6606 spin_lock_irq(&ctx->completion_lock);
6607 ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
6608 spin_unlock_irq(&ctx->completion_lock);
6609}
6610
Jens Axboe3f0e64d2020-09-02 12:42:47 -06006611static int io_sq_wake_function(struct wait_queue_entry *wqe, unsigned mode,
6612 int sync, void *key)
Jens Axboe6c271ce2019-01-10 11:22:30 -07006613{
Jens Axboe3f0e64d2020-09-02 12:42:47 -06006614 struct io_ring_ctx *ctx = container_of(wqe, struct io_ring_ctx, sqo_wait_entry);
6615 int ret;
6616
6617 ret = autoremove_wake_function(wqe, mode, sync, key);
6618 if (ret) {
6619 unsigned long flags;
6620
6621 spin_lock_irqsave(&ctx->completion_lock, flags);
6622 ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
6623 spin_unlock_irqrestore(&ctx->completion_lock, flags);
6624 }
6625 return ret;
6626}
6627
Jens Axboec8d1ba52020-09-14 11:07:26 -06006628enum sq_ret {
6629 SQT_IDLE = 1,
6630 SQT_SPIN = 2,
6631 SQT_DID_WORK = 4,
6632};
6633
6634static enum sq_ret __io_sq_thread(struct io_ring_ctx *ctx,
Jens Axboee95eee22020-09-08 09:11:32 -06006635 unsigned long start_jiffies, bool cap_entries)
Jens Axboec8d1ba52020-09-14 11:07:26 -06006636{
6637 unsigned long timeout = start_jiffies + ctx->sq_thread_idle;
Jens Axboe534ca6d2020-09-02 13:52:19 -06006638 struct io_sq_data *sqd = ctx->sq_data;
Jens Axboec8d1ba52020-09-14 11:07:26 -06006639 unsigned int to_submit;
Xiaoguang Wangbdcd3ea2020-02-25 22:12:08 +08006640 int ret = 0;
Jens Axboe6c271ce2019-01-10 11:22:30 -07006641
Jens Axboec8d1ba52020-09-14 11:07:26 -06006642again:
6643 if (!list_empty(&ctx->iopoll_list)) {
6644 unsigned nr_events = 0;
Jackie Liua4c0b3d2019-07-08 13:41:12 +08006645
Jens Axboec8d1ba52020-09-14 11:07:26 -06006646 mutex_lock(&ctx->uring_lock);
6647 if (!list_empty(&ctx->iopoll_list) && !need_resched())
6648 io_do_iopoll(ctx, &nr_events, 0);
6649 mutex_unlock(&ctx->uring_lock);
6650 }
Jens Axboe6c271ce2019-01-10 11:22:30 -07006651
Jens Axboec8d1ba52020-09-14 11:07:26 -06006652 to_submit = io_sqring_entries(ctx);
Jens Axboe6c271ce2019-01-10 11:22:30 -07006653
Jens Axboec8d1ba52020-09-14 11:07:26 -06006654 /*
6655 * If submit got -EBUSY, flag us as needing the application
6656 * to enter the kernel to reap and flush events.
6657 */
6658 if (!to_submit || ret == -EBUSY || need_resched()) {
6659 /*
6660 * Drop cur_mm before scheduling, we can't hold it for
6661 * long periods (or over schedule()). Do this before
6662 * adding ourselves to the waitqueue, as the unuse/drop
6663 * may sleep.
6664 */
6665 io_sq_thread_drop_mm();
Jens Axboe6c271ce2019-01-10 11:22:30 -07006666
Jens Axboec8d1ba52020-09-14 11:07:26 -06006667 /*
6668 * We're polling. If we're within the defined idle
6669 * period, then let us spin without work before going
6670 * to sleep. The exception is if we got EBUSY doing
6671 * more IO, we should wait for the application to
6672 * reap events and wake us up.
6673 */
6674 if (!list_empty(&ctx->iopoll_list) || need_resched() ||
6675 (!time_after(jiffies, timeout) && ret != -EBUSY &&
6676 !percpu_ref_is_dying(&ctx->refs)))
6677 return SQT_SPIN;
6678
Jens Axboe534ca6d2020-09-02 13:52:19 -06006679 prepare_to_wait(&sqd->wait, &ctx->sqo_wait_entry,
Jens Axboec8d1ba52020-09-14 11:07:26 -06006680 TASK_INTERRUPTIBLE);
6681
6682 /*
6683 * While doing polled IO, before going to sleep, we need
6684 * to check if there are new reqs added to iopoll_list,
6685 * it is because reqs may have been punted to io worker
6686 * and will be added to iopoll_list later, hence check
6687 * the iopoll_list again.
6688 */
6689 if ((ctx->flags & IORING_SETUP_IOPOLL) &&
6690 !list_empty_careful(&ctx->iopoll_list)) {
Jens Axboe534ca6d2020-09-02 13:52:19 -06006691 finish_wait(&sqd->wait, &ctx->sqo_wait_entry);
Jens Axboec8d1ba52020-09-14 11:07:26 -06006692 goto again;
Jens Axboe6c271ce2019-01-10 11:22:30 -07006693 }
6694
Pavel Begunkovfb5ccc92019-10-25 12:31:30 +03006695 to_submit = io_sqring_entries(ctx);
Jens Axboec8d1ba52020-09-14 11:07:26 -06006696 if (!to_submit || ret == -EBUSY)
6697 return SQT_IDLE;
6698 }
6699
Jens Axboe534ca6d2020-09-02 13:52:19 -06006700 finish_wait(&sqd->wait, &ctx->sqo_wait_entry);
Jens Axboec8d1ba52020-09-14 11:07:26 -06006701 io_ring_clear_wakeup_flag(ctx);
6702
Jens Axboee95eee22020-09-08 09:11:32 -06006703 /* if we're handling multiple rings, cap submit size for fairness */
6704 if (cap_entries && to_submit > 8)
6705 to_submit = 8;
6706
Jens Axboec8d1ba52020-09-14 11:07:26 -06006707 mutex_lock(&ctx->uring_lock);
6708 if (likely(!percpu_ref_is_dying(&ctx->refs)))
6709 ret = io_submit_sqes(ctx, to_submit);
6710 mutex_unlock(&ctx->uring_lock);
Jens Axboe90554202020-09-03 12:12:41 -06006711
6712 if (!io_sqring_full(ctx) && wq_has_sleeper(&ctx->sqo_sq_wait))
6713 wake_up(&ctx->sqo_sq_wait);
6714
Jens Axboec8d1ba52020-09-14 11:07:26 -06006715 return SQT_DID_WORK;
6716}
6717
Jens Axboe69fb2132020-09-14 11:16:23 -06006718static void io_sqd_init_new(struct io_sq_data *sqd)
6719{
6720 struct io_ring_ctx *ctx;
6721
6722 while (!list_empty(&sqd->ctx_new_list)) {
6723 ctx = list_first_entry(&sqd->ctx_new_list, struct io_ring_ctx, sqd_list);
6724 init_wait(&ctx->sqo_wait_entry);
6725 ctx->sqo_wait_entry.func = io_sq_wake_function;
6726 list_move_tail(&ctx->sqd_list, &sqd->ctx_list);
6727 complete(&ctx->sq_thread_comp);
6728 }
6729}
6730
Jens Axboe6c271ce2019-01-10 11:22:30 -07006731static int io_sq_thread(void *data)
6732{
Dennis Zhou91d8f512020-09-16 13:41:05 -07006733 struct cgroup_subsys_state *cur_css = NULL;
Jens Axboe69fb2132020-09-14 11:16:23 -06006734 const struct cred *old_cred = NULL;
6735 struct io_sq_data *sqd = data;
6736 struct io_ring_ctx *ctx;
Jens Axboec8d1ba52020-09-14 11:07:26 -06006737 unsigned long start_jiffies;
Jens Axboe6c271ce2019-01-10 11:22:30 -07006738
Jens Axboec8d1ba52020-09-14 11:07:26 -06006739 start_jiffies = jiffies;
Jens Axboe69fb2132020-09-14 11:16:23 -06006740 while (!kthread_should_stop()) {
6741 enum sq_ret ret = 0;
Jens Axboee95eee22020-09-08 09:11:32 -06006742 bool cap_entries;
Jens Axboec1edbf52019-11-10 16:56:04 -07006743
6744 /*
Jens Axboe69fb2132020-09-14 11:16:23 -06006745 * Any changes to the sqd lists are synchronized through the
6746 * kthread parking. This synchronizes the thread vs users,
6747 * the users are synchronized on the sqd->ctx_lock.
Jens Axboec1edbf52019-11-10 16:56:04 -07006748 */
Jens Axboe69fb2132020-09-14 11:16:23 -06006749 if (kthread_should_park())
6750 kthread_parkme();
6751
6752 if (unlikely(!list_empty(&sqd->ctx_new_list)))
6753 io_sqd_init_new(sqd);
6754
Jens Axboee95eee22020-09-08 09:11:32 -06006755 cap_entries = !list_is_singular(&sqd->ctx_list);
6756
Jens Axboe69fb2132020-09-14 11:16:23 -06006757 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
6758 if (current->cred != ctx->creds) {
6759 if (old_cred)
6760 revert_creds(old_cred);
6761 old_cred = override_creds(ctx->creds);
6762 }
Dennis Zhou91d8f512020-09-16 13:41:05 -07006763 io_sq_thread_associate_blkcg(ctx, &cur_css);
Jens Axboe4ea33a92020-10-15 13:46:44 -06006764#ifdef CONFIG_AUDIT
6765 current->loginuid = ctx->loginuid;
6766 current->sessionid = ctx->sessionid;
6767#endif
Jens Axboe69fb2132020-09-14 11:16:23 -06006768
Jens Axboee95eee22020-09-08 09:11:32 -06006769 ret |= __io_sq_thread(ctx, start_jiffies, cap_entries);
Jens Axboe69fb2132020-09-14 11:16:23 -06006770
Jens Axboe4349f302020-07-09 15:07:01 -06006771 io_sq_thread_drop_mm();
Jens Axboe6c271ce2019-01-10 11:22:30 -07006772 }
6773
Jens Axboe69fb2132020-09-14 11:16:23 -06006774 if (ret & SQT_SPIN) {
Jens Axboec8d1ba52020-09-14 11:07:26 -06006775 io_run_task_work();
6776 cond_resched();
Jens Axboe69fb2132020-09-14 11:16:23 -06006777 } else if (ret == SQT_IDLE) {
6778 if (kthread_should_park())
6779 continue;
6780 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6781 io_ring_set_wakeup_flag(ctx);
6782 schedule();
6783 start_jiffies = jiffies;
6784 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6785 io_ring_clear_wakeup_flag(ctx);
Jens Axboe6c271ce2019-01-10 11:22:30 -07006786 }
Jens Axboe6c271ce2019-01-10 11:22:30 -07006787 }
6788
Jens Axboe4c6e2772020-07-01 11:29:10 -06006789 io_run_task_work();
Jens Axboeb41e9852020-02-17 09:52:41 -07006790
Dennis Zhou91d8f512020-09-16 13:41:05 -07006791 if (cur_css)
6792 io_sq_thread_unassociate_blkcg();
Jens Axboe69fb2132020-09-14 11:16:23 -06006793 if (old_cred)
6794 revert_creds(old_cred);
Jens Axboe06058632019-04-13 09:26:03 -06006795
Roman Penyaev2bbcd6d2019-05-16 10:53:57 +02006796 kthread_parkme();
Jens Axboe06058632019-04-13 09:26:03 -06006797
Jens Axboe6c271ce2019-01-10 11:22:30 -07006798 return 0;
6799}
6800
Jens Axboebda52162019-09-24 13:47:15 -06006801struct io_wait_queue {
6802 struct wait_queue_entry wq;
6803 struct io_ring_ctx *ctx;
6804 unsigned to_wait;
6805 unsigned nr_timeouts;
6806};
6807
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07006808static inline bool io_should_wake(struct io_wait_queue *iowq, bool noflush)
Jens Axboebda52162019-09-24 13:47:15 -06006809{
6810 struct io_ring_ctx *ctx = iowq->ctx;
6811
6812 /*
Brian Gianforcarod195a662019-12-13 03:09:50 -08006813 * Wake up if we have enough events, or if a timeout occurred since we
Jens Axboebda52162019-09-24 13:47:15 -06006814 * started waiting. For timeouts, we always want to return to userspace,
6815 * regardless of event count.
6816 */
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07006817 return io_cqring_events(ctx, noflush) >= iowq->to_wait ||
Jens Axboebda52162019-09-24 13:47:15 -06006818 atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
6819}
6820
6821static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
6822 int wake_flags, void *key)
6823{
6824 struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
6825 wq);
6826
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07006827 /* use noflush == true, as we can't safely rely on locking context */
6828 if (!io_should_wake(iowq, true))
Jens Axboebda52162019-09-24 13:47:15 -06006829 return -1;
6830
6831 return autoremove_wake_function(curr, mode, wake_flags, key);
6832}
6833
Jens Axboeaf9c1a42020-09-24 13:32:18 -06006834static int io_run_task_work_sig(void)
6835{
6836 if (io_run_task_work())
6837 return 1;
6838 if (!signal_pending(current))
6839 return 0;
Jens Axboe792ee0f62020-10-22 20:17:18 -06006840 if (test_tsk_thread_flag(current, TIF_NOTIFY_SIGNAL))
6841 return -ERESTARTSYS;
Jens Axboeaf9c1a42020-09-24 13:32:18 -06006842 return -EINTR;
6843}
6844
Jens Axboe2b188cc2019-01-07 10:46:33 -07006845/*
6846 * Wait until events become available, if we don't already have some. The
6847 * application must reap them itself, as they reside on the shared cq ring.
6848 */
6849static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
6850 const sigset_t __user *sig, size_t sigsz)
6851{
Jens Axboebda52162019-09-24 13:47:15 -06006852 struct io_wait_queue iowq = {
6853 .wq = {
6854 .private = current,
6855 .func = io_wake_function,
6856 .entry = LIST_HEAD_INIT(iowq.wq.entry),
6857 },
6858 .ctx = ctx,
6859 .to_wait = min_events,
6860 };
Hristo Venev75b28af2019-08-26 17:23:46 +00006861 struct io_rings *rings = ctx->rings;
Jackie Liue9ffa5c2019-10-29 11:16:42 +08006862 int ret = 0;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006863
Jens Axboeb41e9852020-02-17 09:52:41 -07006864 do {
6865 if (io_cqring_events(ctx, false) >= min_events)
6866 return 0;
Jens Axboe4c6e2772020-07-01 11:29:10 -06006867 if (!io_run_task_work())
Jens Axboeb41e9852020-02-17 09:52:41 -07006868 break;
Jens Axboeb41e9852020-02-17 09:52:41 -07006869 } while (1);
Jens Axboe2b188cc2019-01-07 10:46:33 -07006870
6871 if (sig) {
Arnd Bergmann9e75ad52019-03-25 15:34:53 +01006872#ifdef CONFIG_COMPAT
6873 if (in_compat_syscall())
6874 ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
Oleg Nesterovb7724342019-07-16 16:29:53 -07006875 sigsz);
Arnd Bergmann9e75ad52019-03-25 15:34:53 +01006876 else
6877#endif
Oleg Nesterovb7724342019-07-16 16:29:53 -07006878 ret = set_user_sigmask(sig, sigsz);
Arnd Bergmann9e75ad52019-03-25 15:34:53 +01006879
Jens Axboe2b188cc2019-01-07 10:46:33 -07006880 if (ret)
6881 return ret;
6882 }
6883
Jens Axboebda52162019-09-24 13:47:15 -06006884 iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
Dmitrii Dolgovc826bd72019-10-15 19:02:01 +02006885 trace_io_uring_cqring_wait(ctx, min_events);
Jens Axboebda52162019-09-24 13:47:15 -06006886 do {
6887 prepare_to_wait_exclusive(&ctx->wait, &iowq.wq,
6888 TASK_INTERRUPTIBLE);
Jens Axboece593a62020-06-30 12:39:05 -06006889 /* make sure we run task_work before checking for signals */
Jens Axboeaf9c1a42020-09-24 13:32:18 -06006890 ret = io_run_task_work_sig();
6891 if (ret > 0)
Jens Axboe4c6e2772020-07-01 11:29:10 -06006892 continue;
Jens Axboeaf9c1a42020-09-24 13:32:18 -06006893 else if (ret < 0)
Jens Axboece593a62020-06-30 12:39:05 -06006894 break;
Jens Axboe1d7bb1d2019-11-06 11:31:17 -07006895 if (io_should_wake(&iowq, false))
Jens Axboebda52162019-09-24 13:47:15 -06006896 break;
6897 schedule();
Jens Axboebda52162019-09-24 13:47:15 -06006898 } while (1);
6899 finish_wait(&ctx->wait, &iowq.wq);
6900
Jens Axboeb7db41c2020-07-04 08:55:50 -06006901 restore_saved_sigmask_unless(ret == -EINTR);
Jens Axboe2b188cc2019-01-07 10:46:33 -07006902
Hristo Venev75b28af2019-08-26 17:23:46 +00006903 return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
Jens Axboe2b188cc2019-01-07 10:46:33 -07006904}
6905
Jens Axboe6b063142019-01-10 22:13:58 -07006906static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
6907{
6908#if defined(CONFIG_UNIX)
6909 if (ctx->ring_sock) {
6910 struct sock *sock = ctx->ring_sock->sk;
6911 struct sk_buff *skb;
6912
6913 while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
6914 kfree_skb(skb);
6915 }
6916#else
6917 int i;
6918
Jens Axboe65e19f52019-10-26 07:20:21 -06006919 for (i = 0; i < ctx->nr_user_files; i++) {
6920 struct file *file;
6921
6922 file = io_file_from_index(ctx, i);
6923 if (file)
6924 fput(file);
6925 }
Jens Axboe6b063142019-01-10 22:13:58 -07006926#endif
6927}
6928
Jens Axboe05f3fb32019-12-09 11:22:50 -07006929static void io_file_ref_kill(struct percpu_ref *ref)
6930{
6931 struct fixed_file_data *data;
6932
6933 data = container_of(ref, struct fixed_file_data, refs);
6934 complete(&data->done);
6935}
6936
Jens Axboe6b063142019-01-10 22:13:58 -07006937static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
6938{
Jens Axboe05f3fb32019-12-09 11:22:50 -07006939 struct fixed_file_data *data = ctx->file_data;
Xiaoguang Wang05589552020-03-31 14:05:18 +08006940 struct fixed_file_ref_node *ref_node = NULL;
Jens Axboe65e19f52019-10-26 07:20:21 -06006941 unsigned nr_tables, i;
6942
Jens Axboe05f3fb32019-12-09 11:22:50 -07006943 if (!data)
Jens Axboe6b063142019-01-10 22:13:58 -07006944 return -ENXIO;
6945
Jens Axboe6a4d07c2020-05-15 14:30:38 -06006946 spin_lock(&data->lock);
Xiaoguang Wang05589552020-03-31 14:05:18 +08006947 if (!list_empty(&data->ref_list))
6948 ref_node = list_first_entry(&data->ref_list,
6949 struct fixed_file_ref_node, node);
Jens Axboe6a4d07c2020-05-15 14:30:38 -06006950 spin_unlock(&data->lock);
Xiaoguang Wang05589552020-03-31 14:05:18 +08006951 if (ref_node)
6952 percpu_ref_kill(&ref_node->refs);
6953
6954 percpu_ref_kill(&data->refs);
6955
6956 /* wait for all refs nodes to complete */
Jens Axboe4a38aed22020-05-14 17:21:15 -06006957 flush_delayed_work(&ctx->file_put_work);
Jens Axboe2faf8522020-02-04 19:54:55 -07006958 wait_for_completion(&data->done);
Jens Axboe05f3fb32019-12-09 11:22:50 -07006959
Jens Axboe6b063142019-01-10 22:13:58 -07006960 __io_sqe_files_unregister(ctx);
Jens Axboe65e19f52019-10-26 07:20:21 -06006961 nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE);
6962 for (i = 0; i < nr_tables; i++)
Jens Axboe05f3fb32019-12-09 11:22:50 -07006963 kfree(data->table[i].files);
6964 kfree(data->table);
Xiaoguang Wang05589552020-03-31 14:05:18 +08006965 percpu_ref_exit(&data->refs);
6966 kfree(data);
Jens Axboe05f3fb32019-12-09 11:22:50 -07006967 ctx->file_data = NULL;
Jens Axboe6b063142019-01-10 22:13:58 -07006968 ctx->nr_user_files = 0;
6969 return 0;
6970}
6971
Jens Axboe534ca6d2020-09-02 13:52:19 -06006972static void io_put_sq_data(struct io_sq_data *sqd)
Jens Axboe6c271ce2019-01-10 11:22:30 -07006973{
Jens Axboe534ca6d2020-09-02 13:52:19 -06006974 if (refcount_dec_and_test(&sqd->refs)) {
Roman Penyaev2bbcd6d2019-05-16 10:53:57 +02006975 /*
6976 * The park is a bit of a work-around, without it we get
6977 * warning spews on shutdown with SQPOLL set and affinity
6978 * set to a single CPU.
6979 */
Jens Axboe534ca6d2020-09-02 13:52:19 -06006980 if (sqd->thread) {
6981 kthread_park(sqd->thread);
6982 kthread_stop(sqd->thread);
6983 }
6984
6985 kfree(sqd);
6986 }
6987}
6988
Jens Axboeaa061652020-09-02 14:50:27 -06006989static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
6990{
6991 struct io_ring_ctx *ctx_attach;
6992 struct io_sq_data *sqd;
6993 struct fd f;
6994
6995 f = fdget(p->wq_fd);
6996 if (!f.file)
6997 return ERR_PTR(-ENXIO);
6998 if (f.file->f_op != &io_uring_fops) {
6999 fdput(f);
7000 return ERR_PTR(-EINVAL);
7001 }
7002
7003 ctx_attach = f.file->private_data;
7004 sqd = ctx_attach->sq_data;
7005 if (!sqd) {
7006 fdput(f);
7007 return ERR_PTR(-EINVAL);
7008 }
7009
7010 refcount_inc(&sqd->refs);
7011 fdput(f);
7012 return sqd;
7013}
7014
Jens Axboe534ca6d2020-09-02 13:52:19 -06007015static struct io_sq_data *io_get_sq_data(struct io_uring_params *p)
7016{
7017 struct io_sq_data *sqd;
7018
Jens Axboeaa061652020-09-02 14:50:27 -06007019 if (p->flags & IORING_SETUP_ATTACH_WQ)
7020 return io_attach_sq_data(p);
7021
Jens Axboe534ca6d2020-09-02 13:52:19 -06007022 sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
7023 if (!sqd)
7024 return ERR_PTR(-ENOMEM);
7025
7026 refcount_set(&sqd->refs, 1);
Jens Axboe69fb2132020-09-14 11:16:23 -06007027 INIT_LIST_HEAD(&sqd->ctx_list);
7028 INIT_LIST_HEAD(&sqd->ctx_new_list);
7029 mutex_init(&sqd->ctx_lock);
7030 mutex_init(&sqd->lock);
Jens Axboe534ca6d2020-09-02 13:52:19 -06007031 init_waitqueue_head(&sqd->wait);
7032 return sqd;
7033}
7034
Jens Axboe69fb2132020-09-14 11:16:23 -06007035static void io_sq_thread_unpark(struct io_sq_data *sqd)
7036 __releases(&sqd->lock)
7037{
7038 if (!sqd->thread)
7039 return;
7040 kthread_unpark(sqd->thread);
7041 mutex_unlock(&sqd->lock);
7042}
7043
7044static void io_sq_thread_park(struct io_sq_data *sqd)
7045 __acquires(&sqd->lock)
7046{
7047 if (!sqd->thread)
7048 return;
7049 mutex_lock(&sqd->lock);
7050 kthread_park(sqd->thread);
7051}
7052
Jens Axboe534ca6d2020-09-02 13:52:19 -06007053static void io_sq_thread_stop(struct io_ring_ctx *ctx)
7054{
7055 struct io_sq_data *sqd = ctx->sq_data;
7056
7057 if (sqd) {
7058 if (sqd->thread) {
7059 /*
7060 * We may arrive here from the error branch in
7061 * io_sq_offload_create() where the kthread is created
7062 * without being waked up, thus wake it up now to make
7063 * sure the wait will complete.
7064 */
7065 wake_up_process(sqd->thread);
7066 wait_for_completion(&ctx->sq_thread_comp);
Jens Axboe69fb2132020-09-14 11:16:23 -06007067
7068 io_sq_thread_park(sqd);
7069 }
7070
7071 mutex_lock(&sqd->ctx_lock);
7072 list_del(&ctx->sqd_list);
7073 mutex_unlock(&sqd->ctx_lock);
7074
7075 if (sqd->thread) {
7076 finish_wait(&sqd->wait, &ctx->sqo_wait_entry);
7077 io_sq_thread_unpark(sqd);
Jens Axboe534ca6d2020-09-02 13:52:19 -06007078 }
7079
7080 io_put_sq_data(sqd);
7081 ctx->sq_data = NULL;
Jens Axboe6c271ce2019-01-10 11:22:30 -07007082 }
7083}
7084
Jens Axboe6b063142019-01-10 22:13:58 -07007085static void io_finish_async(struct io_ring_ctx *ctx)
7086{
Jens Axboe6c271ce2019-01-10 11:22:30 -07007087 io_sq_thread_stop(ctx);
7088
Jens Axboe561fb042019-10-24 07:25:42 -06007089 if (ctx->io_wq) {
7090 io_wq_destroy(ctx->io_wq);
7091 ctx->io_wq = NULL;
Jens Axboe6b063142019-01-10 22:13:58 -07007092 }
7093}
7094
7095#if defined(CONFIG_UNIX)
Jens Axboe6b063142019-01-10 22:13:58 -07007096/*
7097 * Ensure the UNIX gc is aware of our file set, so we are certain that
7098 * the io_uring can be safely unregistered on process exit, even if we have
7099 * loops in the file referencing.
7100 */
7101static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
7102{
7103 struct sock *sk = ctx->ring_sock->sk;
7104 struct scm_fp_list *fpl;
7105 struct sk_buff *skb;
Jens Axboe08a45172019-10-03 08:11:03 -06007106 int i, nr_files;
Jens Axboe6b063142019-01-10 22:13:58 -07007107
Jens Axboe6b063142019-01-10 22:13:58 -07007108 fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
7109 if (!fpl)
7110 return -ENOMEM;
7111
7112 skb = alloc_skb(0, GFP_KERNEL);
7113 if (!skb) {
7114 kfree(fpl);
7115 return -ENOMEM;
7116 }
7117
7118 skb->sk = sk;
Jens Axboe6b063142019-01-10 22:13:58 -07007119
Jens Axboe08a45172019-10-03 08:11:03 -06007120 nr_files = 0;
Jens Axboe6b063142019-01-10 22:13:58 -07007121 fpl->user = get_uid(ctx->user);
7122 for (i = 0; i < nr; i++) {
Jens Axboe65e19f52019-10-26 07:20:21 -06007123 struct file *file = io_file_from_index(ctx, i + offset);
7124
7125 if (!file)
Jens Axboe08a45172019-10-03 08:11:03 -06007126 continue;
Jens Axboe65e19f52019-10-26 07:20:21 -06007127 fpl->fp[nr_files] = get_file(file);
Jens Axboe08a45172019-10-03 08:11:03 -06007128 unix_inflight(fpl->user, fpl->fp[nr_files]);
7129 nr_files++;
Jens Axboe6b063142019-01-10 22:13:58 -07007130 }
7131
Jens Axboe08a45172019-10-03 08:11:03 -06007132 if (nr_files) {
7133 fpl->max = SCM_MAX_FD;
7134 fpl->count = nr_files;
7135 UNIXCB(skb).fp = fpl;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007136 skb->destructor = unix_destruct_scm;
Jens Axboe08a45172019-10-03 08:11:03 -06007137 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
7138 skb_queue_head(&sk->sk_receive_queue, skb);
Jens Axboe6b063142019-01-10 22:13:58 -07007139
Jens Axboe08a45172019-10-03 08:11:03 -06007140 for (i = 0; i < nr_files; i++)
7141 fput(fpl->fp[i]);
7142 } else {
7143 kfree_skb(skb);
7144 kfree(fpl);
7145 }
Jens Axboe6b063142019-01-10 22:13:58 -07007146
7147 return 0;
7148}
7149
7150/*
7151 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7152 * causes regular reference counting to break down. We rely on the UNIX
7153 * garbage collection to take care of this problem for us.
7154 */
7155static int io_sqe_files_scm(struct io_ring_ctx *ctx)
7156{
7157 unsigned left, total;
7158 int ret = 0;
7159
7160 total = 0;
7161 left = ctx->nr_user_files;
7162 while (left) {
7163 unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
Jens Axboe6b063142019-01-10 22:13:58 -07007164
7165 ret = __io_sqe_files_scm(ctx, this_files, total);
7166 if (ret)
7167 break;
7168 left -= this_files;
7169 total += this_files;
7170 }
7171
7172 if (!ret)
7173 return 0;
7174
7175 while (total < ctx->nr_user_files) {
Jens Axboe65e19f52019-10-26 07:20:21 -06007176 struct file *file = io_file_from_index(ctx, total);
7177
7178 if (file)
7179 fput(file);
Jens Axboe6b063142019-01-10 22:13:58 -07007180 total++;
7181 }
7182
7183 return ret;
7184}
7185#else
7186static int io_sqe_files_scm(struct io_ring_ctx *ctx)
7187{
7188 return 0;
7189}
7190#endif
7191
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007192static int io_sqe_alloc_file_tables(struct fixed_file_data *file_data,
7193 unsigned nr_tables, unsigned nr_files)
Jens Axboe65e19f52019-10-26 07:20:21 -06007194{
7195 int i;
7196
7197 for (i = 0; i < nr_tables; i++) {
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007198 struct fixed_file_table *table = &file_data->table[i];
Jens Axboe65e19f52019-10-26 07:20:21 -06007199 unsigned this_files;
7200
7201 this_files = min(nr_files, IORING_MAX_FILES_TABLE);
7202 table->files = kcalloc(this_files, sizeof(struct file *),
7203 GFP_KERNEL);
7204 if (!table->files)
7205 break;
7206 nr_files -= this_files;
7207 }
7208
7209 if (i == nr_tables)
7210 return 0;
7211
7212 for (i = 0; i < nr_tables; i++) {
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007213 struct fixed_file_table *table = &file_data->table[i];
Jens Axboe65e19f52019-10-26 07:20:21 -06007214 kfree(table->files);
7215 }
7216 return 1;
7217}
7218
Jens Axboe05f3fb32019-12-09 11:22:50 -07007219static void io_ring_file_put(struct io_ring_ctx *ctx, struct file *file)
Jens Axboec3a31e62019-10-03 13:59:56 -06007220{
7221#if defined(CONFIG_UNIX)
Jens Axboec3a31e62019-10-03 13:59:56 -06007222 struct sock *sock = ctx->ring_sock->sk;
7223 struct sk_buff_head list, *head = &sock->sk_receive_queue;
7224 struct sk_buff *skb;
7225 int i;
7226
7227 __skb_queue_head_init(&list);
7228
7229 /*
7230 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7231 * remove this entry and rearrange the file array.
7232 */
7233 skb = skb_dequeue(head);
7234 while (skb) {
7235 struct scm_fp_list *fp;
7236
7237 fp = UNIXCB(skb).fp;
7238 for (i = 0; i < fp->count; i++) {
7239 int left;
7240
7241 if (fp->fp[i] != file)
7242 continue;
7243
7244 unix_notinflight(fp->user, fp->fp[i]);
7245 left = fp->count - 1 - i;
7246 if (left) {
7247 memmove(&fp->fp[i], &fp->fp[i + 1],
7248 left * sizeof(struct file *));
7249 }
7250 fp->count--;
7251 if (!fp->count) {
7252 kfree_skb(skb);
7253 skb = NULL;
7254 } else {
7255 __skb_queue_tail(&list, skb);
7256 }
7257 fput(file);
7258 file = NULL;
7259 break;
7260 }
7261
7262 if (!file)
7263 break;
7264
7265 __skb_queue_tail(&list, skb);
7266
7267 skb = skb_dequeue(head);
7268 }
7269
7270 if (skb_peek(&list)) {
7271 spin_lock_irq(&head->lock);
7272 while ((skb = __skb_dequeue(&list)) != NULL)
7273 __skb_queue_tail(head, skb);
7274 spin_unlock_irq(&head->lock);
7275 }
7276#else
Jens Axboe05f3fb32019-12-09 11:22:50 -07007277 fput(file);
Jens Axboec3a31e62019-10-03 13:59:56 -06007278#endif
7279}
7280
Jens Axboe05f3fb32019-12-09 11:22:50 -07007281struct io_file_put {
Xiaoguang Wang05589552020-03-31 14:05:18 +08007282 struct list_head list;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007283 struct file *file;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007284};
7285
Jens Axboe4a38aed22020-05-14 17:21:15 -06007286static void __io_file_put_work(struct fixed_file_ref_node *ref_node)
Jens Axboe05f3fb32019-12-09 11:22:50 -07007287{
Jens Axboe4a38aed22020-05-14 17:21:15 -06007288 struct fixed_file_data *file_data = ref_node->file_data;
7289 struct io_ring_ctx *ctx = file_data->ctx;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007290 struct io_file_put *pfile, *tmp;
Xiaoguang Wang05589552020-03-31 14:05:18 +08007291
7292 list_for_each_entry_safe(pfile, tmp, &ref_node->file_list, list) {
Jens Axboe6a4d07c2020-05-15 14:30:38 -06007293 list_del(&pfile->list);
Xiaoguang Wang05589552020-03-31 14:05:18 +08007294 io_ring_file_put(ctx, pfile->file);
7295 kfree(pfile);
Jens Axboe05f3fb32019-12-09 11:22:50 -07007296 }
7297
Jens Axboe6a4d07c2020-05-15 14:30:38 -06007298 spin_lock(&file_data->lock);
7299 list_del(&ref_node->node);
7300 spin_unlock(&file_data->lock);
Jens Axboe2faf8522020-02-04 19:54:55 -07007301
Xiaoguang Wang05589552020-03-31 14:05:18 +08007302 percpu_ref_exit(&ref_node->refs);
7303 kfree(ref_node);
7304 percpu_ref_put(&file_data->refs);
Jens Axboe05f3fb32019-12-09 11:22:50 -07007305}
7306
Jens Axboe4a38aed22020-05-14 17:21:15 -06007307static void io_file_put_work(struct work_struct *work)
7308{
7309 struct io_ring_ctx *ctx;
7310 struct llist_node *node;
7311
7312 ctx = container_of(work, struct io_ring_ctx, file_put_work.work);
7313 node = llist_del_all(&ctx->file_put_llist);
7314
7315 while (node) {
7316 struct fixed_file_ref_node *ref_node;
7317 struct llist_node *next = node->next;
7318
7319 ref_node = llist_entry(node, struct fixed_file_ref_node, llist);
7320 __io_file_put_work(ref_node);
7321 node = next;
7322 }
7323}
7324
Jens Axboe05f3fb32019-12-09 11:22:50 -07007325static void io_file_data_ref_zero(struct percpu_ref *ref)
7326{
Xiaoguang Wang05589552020-03-31 14:05:18 +08007327 struct fixed_file_ref_node *ref_node;
Jens Axboe4a38aed22020-05-14 17:21:15 -06007328 struct io_ring_ctx *ctx;
7329 bool first_add;
7330 int delay = HZ;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007331
Xiaoguang Wang05589552020-03-31 14:05:18 +08007332 ref_node = container_of(ref, struct fixed_file_ref_node, refs);
Jens Axboe4a38aed22020-05-14 17:21:15 -06007333 ctx = ref_node->file_data->ctx;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007334
Jens Axboe4a38aed22020-05-14 17:21:15 -06007335 if (percpu_ref_is_dying(&ctx->file_data->refs))
7336 delay = 0;
7337
7338 first_add = llist_add(&ref_node->llist, &ctx->file_put_llist);
7339 if (!delay)
7340 mod_delayed_work(system_wq, &ctx->file_put_work, 0);
7341 else if (first_add)
7342 queue_delayed_work(system_wq, &ctx->file_put_work, delay);
Xiaoguang Wang05589552020-03-31 14:05:18 +08007343}
7344
7345static struct fixed_file_ref_node *alloc_fixed_file_ref_node(
7346 struct io_ring_ctx *ctx)
7347{
7348 struct fixed_file_ref_node *ref_node;
7349
7350 ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
7351 if (!ref_node)
7352 return ERR_PTR(-ENOMEM);
7353
7354 if (percpu_ref_init(&ref_node->refs, io_file_data_ref_zero,
7355 0, GFP_KERNEL)) {
7356 kfree(ref_node);
7357 return ERR_PTR(-ENOMEM);
7358 }
7359 INIT_LIST_HEAD(&ref_node->node);
7360 INIT_LIST_HEAD(&ref_node->file_list);
Xiaoguang Wang05589552020-03-31 14:05:18 +08007361 ref_node->file_data = ctx->file_data;
7362 return ref_node;
Xiaoguang Wang05589552020-03-31 14:05:18 +08007363}
7364
7365static void destroy_fixed_file_ref_node(struct fixed_file_ref_node *ref_node)
7366{
7367 percpu_ref_exit(&ref_node->refs);
7368 kfree(ref_node);
Jens Axboe05f3fb32019-12-09 11:22:50 -07007369}
7370
7371static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
7372 unsigned nr_args)
7373{
7374 __s32 __user *fds = (__s32 __user *) arg;
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007375 unsigned nr_tables, i;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007376 struct file *file;
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007377 int fd, ret = -ENOMEM;
Xiaoguang Wang05589552020-03-31 14:05:18 +08007378 struct fixed_file_ref_node *ref_node;
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007379 struct fixed_file_data *file_data;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007380
7381 if (ctx->file_data)
7382 return -EBUSY;
7383 if (!nr_args)
7384 return -EINVAL;
7385 if (nr_args > IORING_MAX_FIXED_FILES)
7386 return -EMFILE;
7387
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007388 file_data = kzalloc(sizeof(*ctx->file_data), GFP_KERNEL);
7389 if (!file_data)
Jens Axboe05f3fb32019-12-09 11:22:50 -07007390 return -ENOMEM;
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007391 file_data->ctx = ctx;
7392 init_completion(&file_data->done);
7393 INIT_LIST_HEAD(&file_data->ref_list);
7394 spin_lock_init(&file_data->lock);
Jens Axboe05f3fb32019-12-09 11:22:50 -07007395
7396 nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE);
Colin Ian King035fbaf2020-10-12 15:03:41 +01007397 file_data->table = kcalloc(nr_tables, sizeof(*file_data->table),
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007398 GFP_KERNEL);
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007399 if (!file_data->table)
7400 goto out_free;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007401
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007402 if (percpu_ref_init(&file_data->refs, io_file_ref_kill,
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007403 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
7404 goto out_free;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007405
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007406 if (io_sqe_alloc_file_tables(file_data, nr_tables, nr_args))
7407 goto out_ref;
Jens Axboe55cbc252020-10-14 07:35:57 -06007408 ctx->file_data = file_data;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007409
7410 for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
7411 struct fixed_file_table *table;
7412 unsigned index;
7413
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007414 if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
7415 ret = -EFAULT;
7416 goto out_fput;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007417 }
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007418 /* allow sparse sets */
7419 if (fd == -1)
7420 continue;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007421
Jens Axboe05f3fb32019-12-09 11:22:50 -07007422 file = fget(fd);
Jens Axboe05f3fb32019-12-09 11:22:50 -07007423 ret = -EBADF;
7424 if (!file)
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007425 goto out_fput;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007426
7427 /*
7428 * Don't allow io_uring instances to be registered. If UNIX
7429 * isn't enabled, then this causes a reference cycle and this
7430 * instance can never get freed. If UNIX is enabled we'll
7431 * handle it just fine, but there's still no point in allowing
7432 * a ring fd as it doesn't support regular read/write anyway.
7433 */
7434 if (file->f_op == &io_uring_fops) {
7435 fput(file);
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007436 goto out_fput;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007437 }
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007438 table = &file_data->table[i >> IORING_FILE_TABLE_SHIFT];
7439 index = i & IORING_FILE_TABLE_MASK;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007440 table->files[index] = file;
7441 }
7442
Jens Axboe05f3fb32019-12-09 11:22:50 -07007443 ret = io_sqe_files_scm(ctx);
Xiaoguang Wang05589552020-03-31 14:05:18 +08007444 if (ret) {
Jens Axboe05f3fb32019-12-09 11:22:50 -07007445 io_sqe_files_unregister(ctx);
Xiaoguang Wang05589552020-03-31 14:05:18 +08007446 return ret;
7447 }
Jens Axboe05f3fb32019-12-09 11:22:50 -07007448
Xiaoguang Wang05589552020-03-31 14:05:18 +08007449 ref_node = alloc_fixed_file_ref_node(ctx);
7450 if (IS_ERR(ref_node)) {
7451 io_sqe_files_unregister(ctx);
7452 return PTR_ERR(ref_node);
7453 }
7454
Pavel Begunkovb2e96852020-10-10 18:34:16 +01007455 file_data->node = ref_node;
Pavel Begunkov5398ae62020-10-10 18:34:14 +01007456 spin_lock(&file_data->lock);
7457 list_add(&ref_node->node, &file_data->ref_list);
7458 spin_unlock(&file_data->lock);
7459 percpu_ref_get(&file_data->refs);
Jens Axboe05f3fb32019-12-09 11:22:50 -07007460 return ret;
Pavel Begunkov600cf3f2020-10-10 18:34:15 +01007461out_fput:
7462 for (i = 0; i < ctx->nr_user_files; i++) {
7463 file = io_file_from_index(ctx, i);
7464 if (file)
7465 fput(file);
7466 }
7467 for (i = 0; i < nr_tables; i++)
7468 kfree(file_data->table[i].files);
7469 ctx->nr_user_files = 0;
7470out_ref:
7471 percpu_ref_exit(&file_data->refs);
7472out_free:
7473 kfree(file_data->table);
7474 kfree(file_data);
Jens Axboe55cbc252020-10-14 07:35:57 -06007475 ctx->file_data = NULL;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007476 return ret;
7477}
7478
Jens Axboec3a31e62019-10-03 13:59:56 -06007479static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
7480 int index)
7481{
7482#if defined(CONFIG_UNIX)
7483 struct sock *sock = ctx->ring_sock->sk;
7484 struct sk_buff_head *head = &sock->sk_receive_queue;
7485 struct sk_buff *skb;
7486
7487 /*
7488 * See if we can merge this file into an existing skb SCM_RIGHTS
7489 * file set. If there's no room, fall back to allocating a new skb
7490 * and filling it in.
7491 */
7492 spin_lock_irq(&head->lock);
7493 skb = skb_peek(head);
7494 if (skb) {
7495 struct scm_fp_list *fpl = UNIXCB(skb).fp;
7496
7497 if (fpl->count < SCM_MAX_FD) {
7498 __skb_unlink(skb, head);
7499 spin_unlock_irq(&head->lock);
7500 fpl->fp[fpl->count] = get_file(file);
7501 unix_inflight(fpl->user, fpl->fp[fpl->count]);
7502 fpl->count++;
7503 spin_lock_irq(&head->lock);
7504 __skb_queue_head(head, skb);
7505 } else {
7506 skb = NULL;
7507 }
7508 }
7509 spin_unlock_irq(&head->lock);
7510
7511 if (skb) {
7512 fput(file);
7513 return 0;
7514 }
7515
7516 return __io_sqe_files_scm(ctx, 1, index);
7517#else
7518 return 0;
7519#endif
7520}
7521
Hillf Dantona5318d32020-03-23 17:47:15 +08007522static int io_queue_file_removal(struct fixed_file_data *data,
Xiaoguang Wang05589552020-03-31 14:05:18 +08007523 struct file *file)
Jens Axboe05f3fb32019-12-09 11:22:50 -07007524{
Hillf Dantona5318d32020-03-23 17:47:15 +08007525 struct io_file_put *pfile;
Pavel Begunkovb2e96852020-10-10 18:34:16 +01007526 struct fixed_file_ref_node *ref_node = data->node;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007527
Jens Axboe05f3fb32019-12-09 11:22:50 -07007528 pfile = kzalloc(sizeof(*pfile), GFP_KERNEL);
Hillf Dantona5318d32020-03-23 17:47:15 +08007529 if (!pfile)
7530 return -ENOMEM;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007531
7532 pfile->file = file;
Xiaoguang Wang05589552020-03-31 14:05:18 +08007533 list_add(&pfile->list, &ref_node->file_list);
7534
Hillf Dantona5318d32020-03-23 17:47:15 +08007535 return 0;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007536}
7537
7538static int __io_sqe_files_update(struct io_ring_ctx *ctx,
7539 struct io_uring_files_update *up,
7540 unsigned nr_args)
7541{
7542 struct fixed_file_data *data = ctx->file_data;
Xiaoguang Wang05589552020-03-31 14:05:18 +08007543 struct fixed_file_ref_node *ref_node;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007544 struct file *file;
Jens Axboec3a31e62019-10-03 13:59:56 -06007545 __s32 __user *fds;
7546 int fd, i, err;
7547 __u32 done;
Xiaoguang Wang05589552020-03-31 14:05:18 +08007548 bool needs_switch = false;
Jens Axboec3a31e62019-10-03 13:59:56 -06007549
Jens Axboe05f3fb32019-12-09 11:22:50 -07007550 if (check_add_overflow(up->offset, nr_args, &done))
Jens Axboec3a31e62019-10-03 13:59:56 -06007551 return -EOVERFLOW;
7552 if (done > ctx->nr_user_files)
7553 return -EINVAL;
7554
Xiaoguang Wang05589552020-03-31 14:05:18 +08007555 ref_node = alloc_fixed_file_ref_node(ctx);
7556 if (IS_ERR(ref_node))
7557 return PTR_ERR(ref_node);
7558
Jens Axboec3a31e62019-10-03 13:59:56 -06007559 done = 0;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007560 fds = u64_to_user_ptr(up->fds);
Jens Axboec3a31e62019-10-03 13:59:56 -06007561 while (nr_args) {
Jens Axboe65e19f52019-10-26 07:20:21 -06007562 struct fixed_file_table *table;
7563 unsigned index;
7564
Jens Axboec3a31e62019-10-03 13:59:56 -06007565 err = 0;
7566 if (copy_from_user(&fd, &fds[done], sizeof(fd))) {
7567 err = -EFAULT;
7568 break;
7569 }
Jens Axboe05f3fb32019-12-09 11:22:50 -07007570 i = array_index_nospec(up->offset, ctx->nr_user_files);
7571 table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT];
Jens Axboe65e19f52019-10-26 07:20:21 -06007572 index = i & IORING_FILE_TABLE_MASK;
7573 if (table->files[index]) {
Jiufei Xue98dfd502020-09-01 13:35:02 +08007574 file = table->files[index];
Hillf Dantona5318d32020-03-23 17:47:15 +08007575 err = io_queue_file_removal(data, file);
7576 if (err)
7577 break;
Jens Axboe65e19f52019-10-26 07:20:21 -06007578 table->files[index] = NULL;
Xiaoguang Wang05589552020-03-31 14:05:18 +08007579 needs_switch = true;
Jens Axboec3a31e62019-10-03 13:59:56 -06007580 }
7581 if (fd != -1) {
Jens Axboec3a31e62019-10-03 13:59:56 -06007582 file = fget(fd);
7583 if (!file) {
7584 err = -EBADF;
7585 break;
7586 }
7587 /*
7588 * Don't allow io_uring instances to be registered. If
7589 * UNIX isn't enabled, then this causes a reference
7590 * cycle and this instance can never get freed. If UNIX
7591 * is enabled we'll handle it just fine, but there's
7592 * still no point in allowing a ring fd as it doesn't
7593 * support regular read/write anyway.
7594 */
7595 if (file->f_op == &io_uring_fops) {
7596 fput(file);
7597 err = -EBADF;
7598 break;
7599 }
Jens Axboe65e19f52019-10-26 07:20:21 -06007600 table->files[index] = file;
Jens Axboec3a31e62019-10-03 13:59:56 -06007601 err = io_sqe_file_register(ctx, file, i);
Yang Yingliangf3bd9da2020-07-09 10:11:41 +00007602 if (err) {
Jiufei Xue95d1c8e2020-09-02 17:59:39 +08007603 table->files[index] = NULL;
Yang Yingliangf3bd9da2020-07-09 10:11:41 +00007604 fput(file);
Jens Axboec3a31e62019-10-03 13:59:56 -06007605 break;
Yang Yingliangf3bd9da2020-07-09 10:11:41 +00007606 }
Jens Axboec3a31e62019-10-03 13:59:56 -06007607 }
7608 nr_args--;
7609 done++;
Jens Axboe05f3fb32019-12-09 11:22:50 -07007610 up->offset++;
7611 }
7612
Xiaoguang Wang05589552020-03-31 14:05:18 +08007613 if (needs_switch) {
Pavel Begunkovb2e96852020-10-10 18:34:16 +01007614 percpu_ref_kill(&data->node->refs);
Jens Axboe6a4d07c2020-05-15 14:30:38 -06007615 spin_lock(&data->lock);
Xiaoguang Wang05589552020-03-31 14:05:18 +08007616 list_add(&ref_node->node, &data->ref_list);
Pavel Begunkovb2e96852020-10-10 18:34:16 +01007617 data->node = ref_node;
Jens Axboe6a4d07c2020-05-15 14:30:38 -06007618 spin_unlock(&data->lock);
Xiaoguang Wang05589552020-03-31 14:05:18 +08007619 percpu_ref_get(&ctx->file_data->refs);
7620 } else
7621 destroy_fixed_file_ref_node(ref_node);
Jens Axboec3a31e62019-10-03 13:59:56 -06007622
7623 return done ? done : err;
7624}
Xiaoguang Wang05589552020-03-31 14:05:18 +08007625
Jens Axboe05f3fb32019-12-09 11:22:50 -07007626static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg,
7627 unsigned nr_args)
7628{
7629 struct io_uring_files_update up;
7630
7631 if (!ctx->file_data)
7632 return -ENXIO;
7633 if (!nr_args)
7634 return -EINVAL;
7635 if (copy_from_user(&up, arg, sizeof(up)))
7636 return -EFAULT;
7637 if (up.resv)
7638 return -EINVAL;
7639
7640 return __io_sqe_files_update(ctx, &up, nr_args);
7641}
Jens Axboec3a31e62019-10-03 13:59:56 -06007642
Pavel Begunkove9fd9392020-03-04 16:14:12 +03007643static void io_free_work(struct io_wq_work *work)
Jens Axboe7d723062019-11-12 22:31:31 -07007644{
7645 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
7646
Pavel Begunkove9fd9392020-03-04 16:14:12 +03007647 /* Consider that io_steal_work() relies on this ref */
Jens Axboe7d723062019-11-12 22:31:31 -07007648 io_put_req(req);
7649}
7650
Pavel Begunkov24369c22020-01-28 03:15:48 +03007651static int io_init_wq_offload(struct io_ring_ctx *ctx,
7652 struct io_uring_params *p)
7653{
7654 struct io_wq_data data;
7655 struct fd f;
7656 struct io_ring_ctx *ctx_attach;
7657 unsigned int concurrency;
7658 int ret = 0;
7659
7660 data.user = ctx->user;
Pavel Begunkove9fd9392020-03-04 16:14:12 +03007661 data.free_work = io_free_work;
Pavel Begunkovf5fa38c2020-06-08 21:08:20 +03007662 data.do_work = io_wq_submit_work;
Pavel Begunkov24369c22020-01-28 03:15:48 +03007663
7664 if (!(p->flags & IORING_SETUP_ATTACH_WQ)) {
7665 /* Do QD, or 4 * CPUS, whatever is smallest */
7666 concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
7667
7668 ctx->io_wq = io_wq_create(concurrency, &data);
7669 if (IS_ERR(ctx->io_wq)) {
7670 ret = PTR_ERR(ctx->io_wq);
7671 ctx->io_wq = NULL;
7672 }
7673 return ret;
7674 }
7675
7676 f = fdget(p->wq_fd);
7677 if (!f.file)
7678 return -EBADF;
7679
7680 if (f.file->f_op != &io_uring_fops) {
7681 ret = -EINVAL;
7682 goto out_fput;
7683 }
7684
7685 ctx_attach = f.file->private_data;
7686 /* @io_wq is protected by holding the fd */
7687 if (!io_wq_get(ctx_attach->io_wq, &data)) {
7688 ret = -EINVAL;
7689 goto out_fput;
7690 }
7691
7692 ctx->io_wq = ctx_attach->io_wq;
7693out_fput:
7694 fdput(f);
7695 return ret;
7696}
7697
Jens Axboe0f212202020-09-13 13:09:39 -06007698static int io_uring_alloc_task_context(struct task_struct *task)
7699{
7700 struct io_uring_task *tctx;
Jens Axboed8a6df12020-10-15 16:24:45 -06007701 int ret;
Jens Axboe0f212202020-09-13 13:09:39 -06007702
7703 tctx = kmalloc(sizeof(*tctx), GFP_KERNEL);
7704 if (unlikely(!tctx))
7705 return -ENOMEM;
7706
Jens Axboed8a6df12020-10-15 16:24:45 -06007707 ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
7708 if (unlikely(ret)) {
7709 kfree(tctx);
7710 return ret;
7711 }
7712
Jens Axboe0f212202020-09-13 13:09:39 -06007713 xa_init(&tctx->xa);
7714 init_waitqueue_head(&tctx->wait);
7715 tctx->last = NULL;
Jens Axboefdaf0832020-10-30 09:37:30 -06007716 atomic_set(&tctx->in_idle, 0);
7717 tctx->sqpoll = false;
Jens Axboe500a3732020-10-15 17:38:03 -06007718 io_init_identity(&tctx->__identity);
7719 tctx->identity = &tctx->__identity;
Jens Axboe0f212202020-09-13 13:09:39 -06007720 task->io_uring = tctx;
7721 return 0;
7722}
7723
7724void __io_uring_free(struct task_struct *tsk)
7725{
7726 struct io_uring_task *tctx = tsk->io_uring;
7727
7728 WARN_ON_ONCE(!xa_empty(&tctx->xa));
Jens Axboe500a3732020-10-15 17:38:03 -06007729 WARN_ON_ONCE(refcount_read(&tctx->identity->count) != 1);
7730 if (tctx->identity != &tctx->__identity)
7731 kfree(tctx->identity);
Jens Axboed8a6df12020-10-15 16:24:45 -06007732 percpu_counter_destroy(&tctx->inflight);
Jens Axboe0f212202020-09-13 13:09:39 -06007733 kfree(tctx);
7734 tsk->io_uring = NULL;
7735}
7736
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02007737static int io_sq_offload_create(struct io_ring_ctx *ctx,
7738 struct io_uring_params *p)
Jens Axboe2b188cc2019-01-07 10:46:33 -07007739{
7740 int ret;
7741
Jens Axboe6c271ce2019-01-10 11:22:30 -07007742 if (ctx->flags & IORING_SETUP_SQPOLL) {
Jens Axboe534ca6d2020-09-02 13:52:19 -06007743 struct io_sq_data *sqd;
7744
Jens Axboe3ec482d2019-04-08 10:51:01 -06007745 ret = -EPERM;
7746 if (!capable(CAP_SYS_ADMIN))
7747 goto err;
7748
Jens Axboe534ca6d2020-09-02 13:52:19 -06007749 sqd = io_get_sq_data(p);
7750 if (IS_ERR(sqd)) {
7751 ret = PTR_ERR(sqd);
7752 goto err;
7753 }
Jens Axboe69fb2132020-09-14 11:16:23 -06007754
Jens Axboe534ca6d2020-09-02 13:52:19 -06007755 ctx->sq_data = sqd;
Jens Axboe69fb2132020-09-14 11:16:23 -06007756 io_sq_thread_park(sqd);
7757 mutex_lock(&sqd->ctx_lock);
7758 list_add(&ctx->sqd_list, &sqd->ctx_new_list);
7759 mutex_unlock(&sqd->ctx_lock);
7760 io_sq_thread_unpark(sqd);
Jens Axboe534ca6d2020-09-02 13:52:19 -06007761
Jens Axboe917257d2019-04-13 09:28:55 -06007762 ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
7763 if (!ctx->sq_thread_idle)
7764 ctx->sq_thread_idle = HZ;
7765
Jens Axboeaa061652020-09-02 14:50:27 -06007766 if (sqd->thread)
7767 goto done;
7768
Jens Axboe6c271ce2019-01-10 11:22:30 -07007769 if (p->flags & IORING_SETUP_SQ_AFF) {
Jens Axboe44a9bd12019-05-14 20:00:30 -06007770 int cpu = p->sq_thread_cpu;
Jens Axboe6c271ce2019-01-10 11:22:30 -07007771
Jens Axboe917257d2019-04-13 09:28:55 -06007772 ret = -EINVAL;
Jens Axboe44a9bd12019-05-14 20:00:30 -06007773 if (cpu >= nr_cpu_ids)
7774 goto err;
Shenghui Wang7889f442019-05-07 16:03:19 +08007775 if (!cpu_online(cpu))
Jens Axboe917257d2019-04-13 09:28:55 -06007776 goto err;
7777
Jens Axboe69fb2132020-09-14 11:16:23 -06007778 sqd->thread = kthread_create_on_cpu(io_sq_thread, sqd,
Jens Axboe534ca6d2020-09-02 13:52:19 -06007779 cpu, "io_uring-sq");
Jens Axboe6c271ce2019-01-10 11:22:30 -07007780 } else {
Jens Axboe69fb2132020-09-14 11:16:23 -06007781 sqd->thread = kthread_create(io_sq_thread, sqd,
Jens Axboe6c271ce2019-01-10 11:22:30 -07007782 "io_uring-sq");
7783 }
Jens Axboe534ca6d2020-09-02 13:52:19 -06007784 if (IS_ERR(sqd->thread)) {
7785 ret = PTR_ERR(sqd->thread);
7786 sqd->thread = NULL;
Jens Axboe6c271ce2019-01-10 11:22:30 -07007787 goto err;
7788 }
Jens Axboe534ca6d2020-09-02 13:52:19 -06007789 ret = io_uring_alloc_task_context(sqd->thread);
Jens Axboe0f212202020-09-13 13:09:39 -06007790 if (ret)
7791 goto err;
Jens Axboe6c271ce2019-01-10 11:22:30 -07007792 } else if (p->flags & IORING_SETUP_SQ_AFF) {
7793 /* Can't have SQ_AFF without SQPOLL */
7794 ret = -EINVAL;
7795 goto err;
7796 }
7797
Jens Axboeaa061652020-09-02 14:50:27 -06007798done:
Pavel Begunkov24369c22020-01-28 03:15:48 +03007799 ret = io_init_wq_offload(ctx, p);
7800 if (ret)
Jens Axboe2b188cc2019-01-07 10:46:33 -07007801 goto err;
Jens Axboe2b188cc2019-01-07 10:46:33 -07007802
7803 return 0;
7804err:
Jens Axboe54a91f32019-09-10 09:15:04 -06007805 io_finish_async(ctx);
Jens Axboe2b188cc2019-01-07 10:46:33 -07007806 return ret;
7807}
7808
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02007809static void io_sq_offload_start(struct io_ring_ctx *ctx)
7810{
Jens Axboe534ca6d2020-09-02 13:52:19 -06007811 struct io_sq_data *sqd = ctx->sq_data;
7812
7813 if ((ctx->flags & IORING_SETUP_SQPOLL) && sqd->thread)
7814 wake_up_process(sqd->thread);
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02007815}
7816
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07007817static inline void __io_unaccount_mem(struct user_struct *user,
7818 unsigned long nr_pages)
Jens Axboe2b188cc2019-01-07 10:46:33 -07007819{
7820 atomic_long_sub(nr_pages, &user->locked_vm);
7821}
7822
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07007823static inline int __io_account_mem(struct user_struct *user,
7824 unsigned long nr_pages)
Jens Axboe2b188cc2019-01-07 10:46:33 -07007825{
7826 unsigned long page_limit, cur_pages, new_pages;
7827
7828 /* Don't allow more pages than we can safely lock */
7829 page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
7830
7831 do {
7832 cur_pages = atomic_long_read(&user->locked_vm);
7833 new_pages = cur_pages + nr_pages;
7834 if (new_pages > page_limit)
7835 return -ENOMEM;
7836 } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
7837 new_pages) != cur_pages);
7838
7839 return 0;
7840}
7841
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -07007842static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages,
7843 enum io_mem_account acct)
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07007844{
Bijan Mottahedehaad5d8d2020-06-16 16:36:08 -07007845 if (ctx->limit_mem)
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07007846 __io_unaccount_mem(ctx->user, nr_pages);
Bijan Mottahedeh30975822020-06-16 16:36:09 -07007847
Jens Axboe2aede0e2020-09-14 10:45:53 -06007848 if (ctx->mm_account) {
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -07007849 if (acct == ACCT_LOCKED)
Jens Axboe2aede0e2020-09-14 10:45:53 -06007850 ctx->mm_account->locked_vm -= nr_pages;
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -07007851 else if (acct == ACCT_PINNED)
Jens Axboe2aede0e2020-09-14 10:45:53 -06007852 atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -07007853 }
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07007854}
7855
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -07007856static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages,
7857 enum io_mem_account acct)
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07007858{
Bijan Mottahedeh30975822020-06-16 16:36:09 -07007859 int ret;
7860
7861 if (ctx->limit_mem) {
7862 ret = __io_account_mem(ctx->user, nr_pages);
7863 if (ret)
7864 return ret;
7865 }
7866
Jens Axboe2aede0e2020-09-14 10:45:53 -06007867 if (ctx->mm_account) {
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -07007868 if (acct == ACCT_LOCKED)
Jens Axboe2aede0e2020-09-14 10:45:53 -06007869 ctx->mm_account->locked_vm += nr_pages;
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -07007870 else if (acct == ACCT_PINNED)
Jens Axboe2aede0e2020-09-14 10:45:53 -06007871 atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
Bijan Mottahedeh2e0464d2020-06-16 16:36:10 -07007872 }
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07007873
7874 return 0;
7875}
7876
Jens Axboe2b188cc2019-01-07 10:46:33 -07007877static void io_mem_free(void *ptr)
7878{
Mark Rutland52e04ef2019-04-30 17:30:21 +01007879 struct page *page;
Jens Axboe2b188cc2019-01-07 10:46:33 -07007880
Mark Rutland52e04ef2019-04-30 17:30:21 +01007881 if (!ptr)
7882 return;
7883
7884 page = virt_to_head_page(ptr);
Jens Axboe2b188cc2019-01-07 10:46:33 -07007885 if (put_page_testzero(page))
7886 free_compound_page(page);
7887}
7888
7889static void *io_mem_alloc(size_t size)
7890{
7891 gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP |
7892 __GFP_NORETRY;
7893
7894 return (void *) __get_free_pages(gfp_flags, get_order(size));
7895}
7896
Hristo Venev75b28af2019-08-26 17:23:46 +00007897static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
7898 size_t *sq_offset)
7899{
7900 struct io_rings *rings;
7901 size_t off, sq_array_size;
7902
7903 off = struct_size(rings, cqes, cq_entries);
7904 if (off == SIZE_MAX)
7905 return SIZE_MAX;
7906
7907#ifdef CONFIG_SMP
7908 off = ALIGN(off, SMP_CACHE_BYTES);
7909 if (off == 0)
7910 return SIZE_MAX;
7911#endif
7912
Dmitry Vyukovb36200f2020-07-11 11:31:11 +02007913 if (sq_offset)
7914 *sq_offset = off;
7915
Hristo Venev75b28af2019-08-26 17:23:46 +00007916 sq_array_size = array_size(sizeof(u32), sq_entries);
7917 if (sq_array_size == SIZE_MAX)
7918 return SIZE_MAX;
7919
7920 if (check_add_overflow(off, sq_array_size, &off))
7921 return SIZE_MAX;
7922
Hristo Venev75b28af2019-08-26 17:23:46 +00007923 return off;
7924}
7925
Jens Axboe2b188cc2019-01-07 10:46:33 -07007926static unsigned long ring_pages(unsigned sq_entries, unsigned cq_entries)
7927{
Hristo Venev75b28af2019-08-26 17:23:46 +00007928 size_t pages;
Jens Axboe2b188cc2019-01-07 10:46:33 -07007929
Hristo Venev75b28af2019-08-26 17:23:46 +00007930 pages = (size_t)1 << get_order(
7931 rings_size(sq_entries, cq_entries, NULL));
7932 pages += (size_t)1 << get_order(
7933 array_size(sizeof(struct io_uring_sqe), sq_entries));
Jens Axboe2b188cc2019-01-07 10:46:33 -07007934
Hristo Venev75b28af2019-08-26 17:23:46 +00007935 return pages;
Jens Axboe2b188cc2019-01-07 10:46:33 -07007936}
7937
Jens Axboeedafcce2019-01-09 09:16:05 -07007938static int io_sqe_buffer_unregister(struct io_ring_ctx *ctx)
7939{
7940 int i, j;
7941
7942 if (!ctx->user_bufs)
7943 return -ENXIO;
7944
7945 for (i = 0; i < ctx->nr_user_bufs; i++) {
7946 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
7947
7948 for (j = 0; j < imu->nr_bvecs; j++)
John Hubbardf1f6a7d2020-01-30 22:13:35 -08007949 unpin_user_page(imu->bvec[j].bv_page);
Jens Axboeedafcce2019-01-09 09:16:05 -07007950
Jens Axboede293932020-09-17 16:19:16 -06007951 if (imu->acct_pages)
7952 io_unaccount_mem(ctx, imu->acct_pages, ACCT_PINNED);
Mark Rutlandd4ef6472019-05-01 16:59:16 +01007953 kvfree(imu->bvec);
Jens Axboeedafcce2019-01-09 09:16:05 -07007954 imu->nr_bvecs = 0;
7955 }
7956
7957 kfree(ctx->user_bufs);
7958 ctx->user_bufs = NULL;
7959 ctx->nr_user_bufs = 0;
7960 return 0;
7961}
7962
7963static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
7964 void __user *arg, unsigned index)
7965{
7966 struct iovec __user *src;
7967
7968#ifdef CONFIG_COMPAT
7969 if (ctx->compat) {
7970 struct compat_iovec __user *ciovs;
7971 struct compat_iovec ciov;
7972
7973 ciovs = (struct compat_iovec __user *) arg;
7974 if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
7975 return -EFAULT;
7976
Jens Axboed55e5f52019-12-11 16:12:15 -07007977 dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
Jens Axboeedafcce2019-01-09 09:16:05 -07007978 dst->iov_len = ciov.iov_len;
7979 return 0;
7980 }
7981#endif
7982 src = (struct iovec __user *) arg;
7983 if (copy_from_user(dst, &src[index], sizeof(*dst)))
7984 return -EFAULT;
7985 return 0;
7986}
7987
Jens Axboede293932020-09-17 16:19:16 -06007988/*
7989 * Not super efficient, but this is just a registration time. And we do cache
7990 * the last compound head, so generally we'll only do a full search if we don't
7991 * match that one.
7992 *
7993 * We check if the given compound head page has already been accounted, to
7994 * avoid double accounting it. This allows us to account the full size of the
7995 * page, not just the constituent pages of a huge page.
7996 */
7997static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
7998 int nr_pages, struct page *hpage)
7999{
8000 int i, j;
8001
8002 /* check current page array */
8003 for (i = 0; i < nr_pages; i++) {
8004 if (!PageCompound(pages[i]))
8005 continue;
8006 if (compound_head(pages[i]) == hpage)
8007 return true;
8008 }
8009
8010 /* check previously registered pages */
8011 for (i = 0; i < ctx->nr_user_bufs; i++) {
8012 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
8013
8014 for (j = 0; j < imu->nr_bvecs; j++) {
8015 if (!PageCompound(imu->bvec[j].bv_page))
8016 continue;
8017 if (compound_head(imu->bvec[j].bv_page) == hpage)
8018 return true;
8019 }
8020 }
8021
8022 return false;
8023}
8024
8025static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
8026 int nr_pages, struct io_mapped_ubuf *imu,
8027 struct page **last_hpage)
8028{
8029 int i, ret;
8030
8031 for (i = 0; i < nr_pages; i++) {
8032 if (!PageCompound(pages[i])) {
8033 imu->acct_pages++;
8034 } else {
8035 struct page *hpage;
8036
8037 hpage = compound_head(pages[i]);
8038 if (hpage == *last_hpage)
8039 continue;
8040 *last_hpage = hpage;
8041 if (headpage_already_acct(ctx, pages, i, hpage))
8042 continue;
8043 imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
8044 }
8045 }
8046
8047 if (!imu->acct_pages)
8048 return 0;
8049
8050 ret = io_account_mem(ctx, imu->acct_pages, ACCT_PINNED);
8051 if (ret)
8052 imu->acct_pages = 0;
8053 return ret;
8054}
8055
Jens Axboeedafcce2019-01-09 09:16:05 -07008056static int io_sqe_buffer_register(struct io_ring_ctx *ctx, void __user *arg,
8057 unsigned nr_args)
8058{
8059 struct vm_area_struct **vmas = NULL;
8060 struct page **pages = NULL;
Jens Axboede293932020-09-17 16:19:16 -06008061 struct page *last_hpage = NULL;
Jens Axboeedafcce2019-01-09 09:16:05 -07008062 int i, j, got_pages = 0;
8063 int ret = -EINVAL;
8064
8065 if (ctx->user_bufs)
8066 return -EBUSY;
8067 if (!nr_args || nr_args > UIO_MAXIOV)
8068 return -EINVAL;
8069
8070 ctx->user_bufs = kcalloc(nr_args, sizeof(struct io_mapped_ubuf),
8071 GFP_KERNEL);
8072 if (!ctx->user_bufs)
8073 return -ENOMEM;
8074
8075 for (i = 0; i < nr_args; i++) {
8076 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
8077 unsigned long off, start, end, ubuf;
8078 int pret, nr_pages;
8079 struct iovec iov;
8080 size_t size;
8081
8082 ret = io_copy_iov(ctx, &iov, arg, i);
8083 if (ret)
Pavel Begunkova2786822019-05-26 12:35:47 +03008084 goto err;
Jens Axboeedafcce2019-01-09 09:16:05 -07008085
8086 /*
8087 * Don't impose further limits on the size and buffer
8088 * constraints here, we'll -EINVAL later when IO is
8089 * submitted if they are wrong.
8090 */
8091 ret = -EFAULT;
8092 if (!iov.iov_base || !iov.iov_len)
8093 goto err;
8094
8095 /* arbitrary limit, but we need something */
8096 if (iov.iov_len > SZ_1G)
8097 goto err;
8098
8099 ubuf = (unsigned long) iov.iov_base;
8100 end = (ubuf + iov.iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
8101 start = ubuf >> PAGE_SHIFT;
8102 nr_pages = end - start;
8103
Jens Axboeedafcce2019-01-09 09:16:05 -07008104 ret = 0;
8105 if (!pages || nr_pages > got_pages) {
Denis Efremova8c73c12020-06-05 12:32:03 +03008106 kvfree(vmas);
8107 kvfree(pages);
Mark Rutlandd4ef6472019-05-01 16:59:16 +01008108 pages = kvmalloc_array(nr_pages, sizeof(struct page *),
Jens Axboeedafcce2019-01-09 09:16:05 -07008109 GFP_KERNEL);
Mark Rutlandd4ef6472019-05-01 16:59:16 +01008110 vmas = kvmalloc_array(nr_pages,
Jens Axboeedafcce2019-01-09 09:16:05 -07008111 sizeof(struct vm_area_struct *),
8112 GFP_KERNEL);
8113 if (!pages || !vmas) {
8114 ret = -ENOMEM;
Jens Axboeedafcce2019-01-09 09:16:05 -07008115 goto err;
8116 }
8117 got_pages = nr_pages;
8118 }
8119
Mark Rutlandd4ef6472019-05-01 16:59:16 +01008120 imu->bvec = kvmalloc_array(nr_pages, sizeof(struct bio_vec),
Jens Axboeedafcce2019-01-09 09:16:05 -07008121 GFP_KERNEL);
8122 ret = -ENOMEM;
Jens Axboede293932020-09-17 16:19:16 -06008123 if (!imu->bvec)
Jens Axboeedafcce2019-01-09 09:16:05 -07008124 goto err;
Jens Axboeedafcce2019-01-09 09:16:05 -07008125
8126 ret = 0;
Michel Lespinassed8ed45c2020-06-08 21:33:25 -07008127 mmap_read_lock(current->mm);
John Hubbard2113b052020-01-30 22:13:13 -08008128 pret = pin_user_pages(ubuf, nr_pages,
Ira Weiny932f4a62019-05-13 17:17:03 -07008129 FOLL_WRITE | FOLL_LONGTERM,
8130 pages, vmas);
Jens Axboeedafcce2019-01-09 09:16:05 -07008131 if (pret == nr_pages) {
8132 /* don't support file backed memory */
8133 for (j = 0; j < nr_pages; j++) {
8134 struct vm_area_struct *vma = vmas[j];
8135
8136 if (vma->vm_file &&
8137 !is_file_hugepages(vma->vm_file)) {
8138 ret = -EOPNOTSUPP;
8139 break;
8140 }
8141 }
8142 } else {
8143 ret = pret < 0 ? pret : -EFAULT;
8144 }
Michel Lespinassed8ed45c2020-06-08 21:33:25 -07008145 mmap_read_unlock(current->mm);
Jens Axboeedafcce2019-01-09 09:16:05 -07008146 if (ret) {
8147 /*
8148 * if we did partial map, or found file backed vmas,
8149 * release any pages we did get
8150 */
John Hubbard27c4d3a2019-08-04 19:32:06 -07008151 if (pret > 0)
John Hubbardf1f6a7d2020-01-30 22:13:35 -08008152 unpin_user_pages(pages, pret);
Jens Axboede293932020-09-17 16:19:16 -06008153 kvfree(imu->bvec);
8154 goto err;
8155 }
8156
8157 ret = io_buffer_account_pin(ctx, pages, pret, imu, &last_hpage);
8158 if (ret) {
8159 unpin_user_pages(pages, pret);
Mark Rutlandd4ef6472019-05-01 16:59:16 +01008160 kvfree(imu->bvec);
Jens Axboeedafcce2019-01-09 09:16:05 -07008161 goto err;
8162 }
8163
8164 off = ubuf & ~PAGE_MASK;
8165 size = iov.iov_len;
8166 for (j = 0; j < nr_pages; j++) {
8167 size_t vec_len;
8168
8169 vec_len = min_t(size_t, size, PAGE_SIZE - off);
8170 imu->bvec[j].bv_page = pages[j];
8171 imu->bvec[j].bv_len = vec_len;
8172 imu->bvec[j].bv_offset = off;
8173 off = 0;
8174 size -= vec_len;
8175 }
8176 /* store original address for later verification */
8177 imu->ubuf = ubuf;
8178 imu->len = iov.iov_len;
8179 imu->nr_bvecs = nr_pages;
8180
8181 ctx->nr_user_bufs++;
8182 }
Mark Rutlandd4ef6472019-05-01 16:59:16 +01008183 kvfree(pages);
8184 kvfree(vmas);
Jens Axboeedafcce2019-01-09 09:16:05 -07008185 return 0;
8186err:
Mark Rutlandd4ef6472019-05-01 16:59:16 +01008187 kvfree(pages);
8188 kvfree(vmas);
Jens Axboeedafcce2019-01-09 09:16:05 -07008189 io_sqe_buffer_unregister(ctx);
8190 return ret;
8191}
8192
Jens Axboe9b402842019-04-11 11:45:41 -06008193static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
8194{
8195 __s32 __user *fds = arg;
8196 int fd;
8197
8198 if (ctx->cq_ev_fd)
8199 return -EBUSY;
8200
8201 if (copy_from_user(&fd, fds, sizeof(*fds)))
8202 return -EFAULT;
8203
8204 ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
8205 if (IS_ERR(ctx->cq_ev_fd)) {
8206 int ret = PTR_ERR(ctx->cq_ev_fd);
8207 ctx->cq_ev_fd = NULL;
8208 return ret;
8209 }
8210
8211 return 0;
8212}
8213
8214static int io_eventfd_unregister(struct io_ring_ctx *ctx)
8215{
8216 if (ctx->cq_ev_fd) {
8217 eventfd_ctx_put(ctx->cq_ev_fd);
8218 ctx->cq_ev_fd = NULL;
8219 return 0;
8220 }
8221
8222 return -ENXIO;
8223}
8224
Jens Axboe5a2e7452020-02-23 16:23:11 -07008225static int __io_destroy_buffers(int id, void *p, void *data)
8226{
8227 struct io_ring_ctx *ctx = data;
8228 struct io_buffer *buf = p;
8229
Jens Axboe067524e2020-03-02 16:32:28 -07008230 __io_remove_buffers(ctx, buf, id, -1U);
Jens Axboe5a2e7452020-02-23 16:23:11 -07008231 return 0;
8232}
8233
8234static void io_destroy_buffers(struct io_ring_ctx *ctx)
8235{
8236 idr_for_each(&ctx->io_buffer_idr, __io_destroy_buffers, ctx);
8237 idr_destroy(&ctx->io_buffer_idr);
8238}
8239
Jens Axboe2b188cc2019-01-07 10:46:33 -07008240static void io_ring_ctx_free(struct io_ring_ctx *ctx)
8241{
Jens Axboe6b063142019-01-10 22:13:58 -07008242 io_finish_async(ctx);
Jens Axboeedafcce2019-01-09 09:16:05 -07008243 io_sqe_buffer_unregister(ctx);
Jens Axboe2aede0e2020-09-14 10:45:53 -06008244
8245 if (ctx->sqo_task) {
8246 put_task_struct(ctx->sqo_task);
8247 ctx->sqo_task = NULL;
8248 mmdrop(ctx->mm_account);
8249 ctx->mm_account = NULL;
Bijan Mottahedeh30975822020-06-16 16:36:09 -07008250 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07008251
Dennis Zhou91d8f512020-09-16 13:41:05 -07008252#ifdef CONFIG_BLK_CGROUP
8253 if (ctx->sqo_blkcg_css)
8254 css_put(ctx->sqo_blkcg_css);
8255#endif
8256
Jens Axboe6b063142019-01-10 22:13:58 -07008257 io_sqe_files_unregister(ctx);
Jens Axboe9b402842019-04-11 11:45:41 -06008258 io_eventfd_unregister(ctx);
Jens Axboe5a2e7452020-02-23 16:23:11 -07008259 io_destroy_buffers(ctx);
Jens Axboe41726c92020-02-23 13:11:42 -07008260 idr_destroy(&ctx->personality_idr);
Jens Axboedef596e2019-01-09 08:59:42 -07008261
Jens Axboe2b188cc2019-01-07 10:46:33 -07008262#if defined(CONFIG_UNIX)
Eric Biggers355e8d22019-06-12 14:58:43 -07008263 if (ctx->ring_sock) {
8264 ctx->ring_sock->file = NULL; /* so that iput() is called */
Jens Axboe2b188cc2019-01-07 10:46:33 -07008265 sock_release(ctx->ring_sock);
Eric Biggers355e8d22019-06-12 14:58:43 -07008266 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07008267#endif
8268
Hristo Venev75b28af2019-08-26 17:23:46 +00008269 io_mem_free(ctx->rings);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008270 io_mem_free(ctx->sq_sqes);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008271
8272 percpu_ref_exit(&ctx->refs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008273 free_uid(ctx->user);
Jens Axboe181e4482019-11-25 08:52:30 -07008274 put_cred(ctx->creds);
Jens Axboe78076bb2019-12-04 19:56:40 -07008275 kfree(ctx->cancel_hash);
Jens Axboe0ddf92e2019-11-08 08:52:53 -07008276 kmem_cache_free(req_cachep, ctx->fallback_req);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008277 kfree(ctx);
8278}
8279
8280static __poll_t io_uring_poll(struct file *file, poll_table *wait)
8281{
8282 struct io_ring_ctx *ctx = file->private_data;
8283 __poll_t mask = 0;
8284
8285 poll_wait(file, &ctx->cq_wait, wait);
Stefan Bühler4f7067c2019-04-24 23:54:17 +02008286 /*
8287 * synchronizes with barrier from wq_has_sleeper call in
8288 * io_commit_cqring
8289 */
Jens Axboe2b188cc2019-01-07 10:46:33 -07008290 smp_rmb();
Jens Axboe90554202020-09-03 12:12:41 -06008291 if (!io_sqring_full(ctx))
Jens Axboe2b188cc2019-01-07 10:46:33 -07008292 mask |= EPOLLOUT | EPOLLWRNORM;
Stefano Garzarella63e5d812020-02-07 13:18:28 +01008293 if (io_cqring_events(ctx, false))
Jens Axboe2b188cc2019-01-07 10:46:33 -07008294 mask |= EPOLLIN | EPOLLRDNORM;
8295
8296 return mask;
8297}
8298
8299static int io_uring_fasync(int fd, struct file *file, int on)
8300{
8301 struct io_ring_ctx *ctx = file->private_data;
8302
8303 return fasync_helper(fd, file, on, &ctx->cq_fasync);
8304}
8305
Jens Axboe071698e2020-01-28 10:04:42 -07008306static int io_remove_personalities(int id, void *p, void *data)
8307{
8308 struct io_ring_ctx *ctx = data;
Jens Axboe1e6fa522020-10-15 08:46:24 -06008309 struct io_identity *iod;
Jens Axboe071698e2020-01-28 10:04:42 -07008310
Jens Axboe1e6fa522020-10-15 08:46:24 -06008311 iod = idr_remove(&ctx->personality_idr, id);
8312 if (iod) {
8313 put_cred(iod->creds);
8314 if (refcount_dec_and_test(&iod->count))
8315 kfree(iod);
8316 }
Jens Axboe071698e2020-01-28 10:04:42 -07008317 return 0;
8318}
8319
Jens Axboe85faa7b2020-04-09 18:14:00 -06008320static void io_ring_exit_work(struct work_struct *work)
8321{
Pavel Begunkovb2edc0a2020-07-07 16:36:22 +03008322 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
8323 exit_work);
Jens Axboe85faa7b2020-04-09 18:14:00 -06008324
Jens Axboe56952e92020-06-17 15:00:04 -06008325 /*
8326 * If we're doing polled IO and end up having requests being
8327 * submitted async (out-of-line), then completions can come in while
8328 * we're waiting for refs to drop. We need to reap these manually,
8329 * as nobody else will be looking for them.
8330 */
Pavel Begunkovb2edc0a2020-07-07 16:36:22 +03008331 do {
Jens Axboe56952e92020-06-17 15:00:04 -06008332 if (ctx->rings)
Jens Axboee6c8aa92020-09-28 13:10:13 -06008333 io_cqring_overflow_flush(ctx, true, NULL, NULL);
Pavel Begunkovb2edc0a2020-07-07 16:36:22 +03008334 io_iopoll_try_reap_events(ctx);
8335 } while (!wait_for_completion_timeout(&ctx->ref_comp, HZ/20));
Jens Axboe85faa7b2020-04-09 18:14:00 -06008336 io_ring_ctx_free(ctx);
8337}
8338
Jens Axboe2b188cc2019-01-07 10:46:33 -07008339static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
8340{
8341 mutex_lock(&ctx->uring_lock);
8342 percpu_ref_kill(&ctx->refs);
8343 mutex_unlock(&ctx->uring_lock);
8344
Jens Axboef3606e32020-09-22 08:18:24 -06008345 io_kill_timeouts(ctx, NULL);
8346 io_poll_remove_all(ctx, NULL);
Jens Axboe561fb042019-10-24 07:25:42 -06008347
8348 if (ctx->io_wq)
8349 io_wq_cancel_all(ctx->io_wq);
8350
Jens Axboe15dff282019-11-13 09:09:23 -07008351 /* if we failed setting up the ctx, we might not have any rings */
8352 if (ctx->rings)
Jens Axboee6c8aa92020-09-28 13:10:13 -06008353 io_cqring_overflow_flush(ctx, true, NULL, NULL);
Pavel Begunkovb2edc0a2020-07-07 16:36:22 +03008354 io_iopoll_try_reap_events(ctx);
Jens Axboe071698e2020-01-28 10:04:42 -07008355 idr_for_each(&ctx->personality_idr, io_remove_personalities, ctx);
Jens Axboe309fc032020-07-10 09:13:34 -06008356
8357 /*
8358 * Do this upfront, so we won't have a grace period where the ring
8359 * is closed but resources aren't reaped yet. This can cause
8360 * spurious failure in setting up a new ring.
8361 */
Jens Axboe760618f2020-07-24 12:53:31 -06008362 io_unaccount_mem(ctx, ring_pages(ctx->sq_entries, ctx->cq_entries),
8363 ACCT_LOCKED);
Jens Axboe309fc032020-07-10 09:13:34 -06008364
Jens Axboe85faa7b2020-04-09 18:14:00 -06008365 INIT_WORK(&ctx->exit_work, io_ring_exit_work);
Jens Axboefc666772020-08-19 11:10:51 -06008366 /*
8367 * Use system_unbound_wq to avoid spawning tons of event kworkers
8368 * if we're exiting a ton of rings at the same time. It just adds
8369 * noise and overhead, there's no discernable change in runtime
8370 * over using system_wq.
8371 */
8372 queue_work(system_unbound_wq, &ctx->exit_work);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008373}
8374
8375static int io_uring_release(struct inode *inode, struct file *file)
8376{
8377 struct io_ring_ctx *ctx = file->private_data;
8378
8379 file->private_data = NULL;
8380 io_ring_ctx_wait_and_kill(ctx);
8381 return 0;
8382}
8383
Pavel Begunkov67c4d9e2020-06-15 10:24:05 +03008384static bool io_wq_files_match(struct io_wq_work *work, void *data)
8385{
8386 struct files_struct *files = data;
8387
Jens Axboedfead8a2020-10-14 10:12:37 -06008388 return !files || ((work->flags & IO_WQ_WORK_FILES) &&
Jens Axboe98447d62020-10-14 10:48:51 -06008389 work->identity->files == files);
Pavel Begunkov67c4d9e2020-06-15 10:24:05 +03008390}
8391
Jens Axboef254ac02020-08-12 17:33:30 -06008392/*
8393 * Returns true if 'preq' is the link parent of 'req'
8394 */
8395static bool io_match_link(struct io_kiocb *preq, struct io_kiocb *req)
8396{
8397 struct io_kiocb *link;
8398
8399 if (!(preq->flags & REQ_F_LINK_HEAD))
8400 return false;
8401
8402 list_for_each_entry(link, &preq->link_list, link_list) {
8403 if (link == req)
8404 return true;
8405 }
8406
8407 return false;
8408}
8409
8410/*
8411 * We're looking to cancel 'req' because it's holding on to our files, but
8412 * 'req' could be a link to another request. See if it is, and cancel that
8413 * parent request if so.
8414 */
8415static bool io_poll_remove_link(struct io_ring_ctx *ctx, struct io_kiocb *req)
8416{
8417 struct hlist_node *tmp;
8418 struct io_kiocb *preq;
8419 bool found = false;
8420 int i;
8421
8422 spin_lock_irq(&ctx->completion_lock);
8423 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
8424 struct hlist_head *list;
8425
8426 list = &ctx->cancel_hash[i];
8427 hlist_for_each_entry_safe(preq, tmp, list, hash_node) {
8428 found = io_match_link(preq, req);
8429 if (found) {
8430 io_poll_remove_one(preq);
8431 break;
8432 }
8433 }
8434 }
8435 spin_unlock_irq(&ctx->completion_lock);
8436 return found;
8437}
8438
8439static bool io_timeout_remove_link(struct io_ring_ctx *ctx,
8440 struct io_kiocb *req)
8441{
8442 struct io_kiocb *preq;
8443 bool found = false;
8444
8445 spin_lock_irq(&ctx->completion_lock);
8446 list_for_each_entry(preq, &ctx->timeout_list, timeout.list) {
8447 found = io_match_link(preq, req);
8448 if (found) {
8449 __io_timeout_cancel(preq);
8450 break;
8451 }
8452 }
8453 spin_unlock_irq(&ctx->completion_lock);
8454 return found;
8455}
8456
Jens Axboeb711d4e2020-08-16 08:23:05 -07008457static bool io_cancel_link_cb(struct io_wq_work *work, void *data)
8458{
Pavel Begunkov9a472ef2020-11-05 22:31:37 +00008459 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8460 bool ret;
8461
8462 if (req->flags & REQ_F_LINK_TIMEOUT) {
8463 unsigned long flags;
8464 struct io_ring_ctx *ctx = req->ctx;
8465
8466 /* protect against races with linked timeouts */
8467 spin_lock_irqsave(&ctx->completion_lock, flags);
8468 ret = io_match_link(req, data);
8469 spin_unlock_irqrestore(&ctx->completion_lock, flags);
8470 } else {
8471 ret = io_match_link(req, data);
8472 }
8473 return ret;
Jens Axboeb711d4e2020-08-16 08:23:05 -07008474}
8475
8476static void io_attempt_cancel(struct io_ring_ctx *ctx, struct io_kiocb *req)
8477{
8478 enum io_wq_cancel cret;
8479
8480 /* cancel this particular work, if it's running */
8481 cret = io_wq_cancel_work(ctx->io_wq, &req->work);
8482 if (cret != IO_WQ_CANCEL_NOTFOUND)
8483 return;
8484
8485 /* find links that hold this pending, cancel those */
8486 cret = io_wq_cancel_cb(ctx->io_wq, io_cancel_link_cb, req, true);
8487 if (cret != IO_WQ_CANCEL_NOTFOUND)
8488 return;
8489
8490 /* if we have a poll link holding this pending, cancel that */
8491 if (io_poll_remove_link(ctx, req))
8492 return;
8493
8494 /* final option, timeout link is holding this req pending */
8495 io_timeout_remove_link(ctx, req);
8496}
8497
Pavel Begunkovb7ddce32020-09-06 00:45:14 +03008498static void io_cancel_defer_files(struct io_ring_ctx *ctx,
Pavel Begunkovef9865a2020-11-05 14:06:19 +00008499 struct task_struct *task,
Pavel Begunkovb7ddce32020-09-06 00:45:14 +03008500 struct files_struct *files)
8501{
8502 struct io_defer_entry *de = NULL;
8503 LIST_HEAD(list);
8504
8505 spin_lock_irq(&ctx->completion_lock);
8506 list_for_each_entry_reverse(de, &ctx->defer_list, list) {
Pavel Begunkovef9865a2020-11-05 14:06:19 +00008507 if (io_task_match(de->req, task) &&
8508 io_match_files(de->req, files)) {
Pavel Begunkovb7ddce32020-09-06 00:45:14 +03008509 list_cut_position(&list, &ctx->defer_list, &de->list);
8510 break;
8511 }
8512 }
8513 spin_unlock_irq(&ctx->completion_lock);
8514
8515 while (!list_empty(&list)) {
8516 de = list_first_entry(&list, struct io_defer_entry, list);
8517 list_del_init(&de->list);
8518 req_set_fail_links(de->req);
8519 io_put_req(de->req);
8520 io_req_complete(de->req, -ECANCELED);
8521 kfree(de);
8522 }
8523}
8524
Jens Axboe76e1b642020-09-26 15:05:03 -06008525/*
8526 * Returns true if we found and killed one or more files pinning requests
8527 */
8528static bool io_uring_cancel_files(struct io_ring_ctx *ctx,
Jens Axboefcb323c2019-10-24 12:39:47 -06008529 struct files_struct *files)
8530{
Pavel Begunkov67c4d9e2020-06-15 10:24:05 +03008531 if (list_empty_careful(&ctx->inflight_list))
Jens Axboe76e1b642020-09-26 15:05:03 -06008532 return false;
Pavel Begunkov67c4d9e2020-06-15 10:24:05 +03008533
8534 /* cancel all at once, should be faster than doing it one by one*/
8535 io_wq_cancel_cb(ctx->io_wq, io_wq_files_match, files, true);
8536
Jens Axboefcb323c2019-10-24 12:39:47 -06008537 while (!list_empty_careful(&ctx->inflight_list)) {
Xiaoguang Wangd8f1b972020-04-26 15:54:43 +08008538 struct io_kiocb *cancel_req = NULL, *req;
8539 DEFINE_WAIT(wait);
Jens Axboefcb323c2019-10-24 12:39:47 -06008540
8541 spin_lock_irq(&ctx->inflight_lock);
8542 list_for_each_entry(req, &ctx->inflight_list, inflight_entry) {
Jens Axboedfead8a2020-10-14 10:12:37 -06008543 if (files && (req->work.flags & IO_WQ_WORK_FILES) &&
Jens Axboe98447d62020-10-14 10:48:51 -06008544 req->work.identity->files != files)
Jens Axboe768134d2019-11-10 20:30:53 -07008545 continue;
8546 /* req is being completed, ignore */
8547 if (!refcount_inc_not_zero(&req->refs))
8548 continue;
8549 cancel_req = req;
8550 break;
Jens Axboefcb323c2019-10-24 12:39:47 -06008551 }
Jens Axboe768134d2019-11-10 20:30:53 -07008552 if (cancel_req)
Jens Axboefcb323c2019-10-24 12:39:47 -06008553 prepare_to_wait(&ctx->inflight_wait, &wait,
Jens Axboe768134d2019-11-10 20:30:53 -07008554 TASK_UNINTERRUPTIBLE);
Jens Axboefcb323c2019-10-24 12:39:47 -06008555 spin_unlock_irq(&ctx->inflight_lock);
8556
Jens Axboe768134d2019-11-10 20:30:53 -07008557 /* We need to keep going until we don't find a matching req */
8558 if (!cancel_req)
Jens Axboefcb323c2019-10-24 12:39:47 -06008559 break;
Pavel Begunkovbb175342020-08-20 11:33:35 +03008560 /* cancel this request, or head link requests */
8561 io_attempt_cancel(ctx, cancel_req);
8562 io_put_req(cancel_req);
Jens Axboe6200b0a2020-09-13 14:38:30 -06008563 /* cancellations _may_ trigger task work */
8564 io_run_task_work();
Jens Axboefcb323c2019-10-24 12:39:47 -06008565 schedule();
Xiaoguang Wangd8f1b972020-04-26 15:54:43 +08008566 finish_wait(&ctx->inflight_wait, &wait);
Jens Axboefcb323c2019-10-24 12:39:47 -06008567 }
Jens Axboe76e1b642020-09-26 15:05:03 -06008568
8569 return true;
Jens Axboefcb323c2019-10-24 12:39:47 -06008570}
8571
Pavel Begunkov801dd572020-06-15 10:33:14 +03008572static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
Pavel Begunkov44e728b2020-06-15 10:24:04 +03008573{
Pavel Begunkov801dd572020-06-15 10:33:14 +03008574 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8575 struct task_struct *task = data;
Pavel Begunkov44e728b2020-06-15 10:24:04 +03008576
Jens Axboef3606e32020-09-22 08:18:24 -06008577 return io_task_match(req, task);
Pavel Begunkov44e728b2020-06-15 10:24:04 +03008578}
8579
Jens Axboe0f212202020-09-13 13:09:39 -06008580static bool __io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
8581 struct task_struct *task,
8582 struct files_struct *files)
8583{
8584 bool ret;
8585
8586 ret = io_uring_cancel_files(ctx, files);
8587 if (!files) {
8588 enum io_wq_cancel cret;
8589
8590 cret = io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, task, true);
8591 if (cret != IO_WQ_CANCEL_NOTFOUND)
8592 ret = true;
8593
8594 /* SQPOLL thread does its own polling */
8595 if (!(ctx->flags & IORING_SETUP_SQPOLL)) {
8596 while (!list_empty_careful(&ctx->iopoll_list)) {
8597 io_iopoll_try_reap_events(ctx);
8598 ret = true;
8599 }
8600 }
8601
8602 ret |= io_poll_remove_all(ctx, task);
8603 ret |= io_kill_timeouts(ctx, task);
8604 }
8605
8606 return ret;
8607}
8608
8609/*
8610 * We need to iteratively cancel requests, in case a request has dependent
8611 * hard links. These persist even for failure of cancelations, hence keep
8612 * looping until none are found.
8613 */
8614static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
8615 struct files_struct *files)
8616{
8617 struct task_struct *task = current;
8618
Jens Axboefdaf0832020-10-30 09:37:30 -06008619 if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
Jens Axboe534ca6d2020-09-02 13:52:19 -06008620 task = ctx->sq_data->thread;
Jens Axboefdaf0832020-10-30 09:37:30 -06008621 atomic_inc(&task->io_uring->in_idle);
8622 io_sq_thread_park(ctx->sq_data);
8623 }
Jens Axboe0f212202020-09-13 13:09:39 -06008624
Pavel Begunkovef9865a2020-11-05 14:06:19 +00008625 if (files)
8626 io_cancel_defer_files(ctx, NULL, files);
8627 else
8628 io_cancel_defer_files(ctx, task, NULL);
8629
Jens Axboe0f212202020-09-13 13:09:39 -06008630 io_cqring_overflow_flush(ctx, true, task, files);
8631
8632 while (__io_uring_cancel_task_requests(ctx, task, files)) {
8633 io_run_task_work();
8634 cond_resched();
8635 }
Jens Axboefdaf0832020-10-30 09:37:30 -06008636
8637 if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
8638 atomic_dec(&task->io_uring->in_idle);
8639 /*
8640 * If the files that are going away are the ones in the thread
8641 * identity, clear them out.
8642 */
8643 if (task->io_uring->identity->files == files)
8644 task->io_uring->identity->files = NULL;
8645 io_sq_thread_unpark(ctx->sq_data);
8646 }
Jens Axboe0f212202020-09-13 13:09:39 -06008647}
8648
8649/*
8650 * Note that this task has used io_uring. We use it for cancelation purposes.
8651 */
Jens Axboefdaf0832020-10-30 09:37:30 -06008652static int io_uring_add_task_file(struct io_ring_ctx *ctx, struct file *file)
Jens Axboe0f212202020-09-13 13:09:39 -06008653{
Matthew Wilcox (Oracle)236434c2020-10-09 13:49:52 +01008654 struct io_uring_task *tctx = current->io_uring;
8655
8656 if (unlikely(!tctx)) {
Jens Axboe0f212202020-09-13 13:09:39 -06008657 int ret;
8658
8659 ret = io_uring_alloc_task_context(current);
8660 if (unlikely(ret))
8661 return ret;
Matthew Wilcox (Oracle)236434c2020-10-09 13:49:52 +01008662 tctx = current->io_uring;
Jens Axboe0f212202020-09-13 13:09:39 -06008663 }
Matthew Wilcox (Oracle)236434c2020-10-09 13:49:52 +01008664 if (tctx->last != file) {
8665 void *old = xa_load(&tctx->xa, (unsigned long)file);
Jens Axboe0f212202020-09-13 13:09:39 -06008666
Matthew Wilcox (Oracle)236434c2020-10-09 13:49:52 +01008667 if (!old) {
Jens Axboe0f212202020-09-13 13:09:39 -06008668 get_file(file);
Matthew Wilcox (Oracle)236434c2020-10-09 13:49:52 +01008669 xa_store(&tctx->xa, (unsigned long)file, file, GFP_KERNEL);
Jens Axboe0f212202020-09-13 13:09:39 -06008670 }
Matthew Wilcox (Oracle)236434c2020-10-09 13:49:52 +01008671 tctx->last = file;
Jens Axboe0f212202020-09-13 13:09:39 -06008672 }
8673
Jens Axboefdaf0832020-10-30 09:37:30 -06008674 /*
8675 * This is race safe in that the task itself is doing this, hence it
8676 * cannot be going through the exit/cancel paths at the same time.
8677 * This cannot be modified while exit/cancel is running.
8678 */
8679 if (!tctx->sqpoll && (ctx->flags & IORING_SETUP_SQPOLL))
8680 tctx->sqpoll = true;
8681
Jens Axboe0f212202020-09-13 13:09:39 -06008682 return 0;
8683}
8684
8685/*
8686 * Remove this io_uring_file -> task mapping.
8687 */
8688static void io_uring_del_task_file(struct file *file)
8689{
8690 struct io_uring_task *tctx = current->io_uring;
Jens Axboe0f212202020-09-13 13:09:39 -06008691
8692 if (tctx->last == file)
8693 tctx->last = NULL;
Matthew Wilcox (Oracle)5e2ed8c2020-10-09 13:49:53 +01008694 file = xa_erase(&tctx->xa, (unsigned long)file);
Jens Axboe0f212202020-09-13 13:09:39 -06008695 if (file)
8696 fput(file);
8697}
8698
Jens Axboe0f212202020-09-13 13:09:39 -06008699/*
8700 * Drop task note for this file if we're the only ones that hold it after
8701 * pending fput()
8702 */
Pavel Begunkovc8fb20b2020-10-22 16:38:27 +01008703static void io_uring_attempt_task_drop(struct file *file)
Jens Axboe0f212202020-09-13 13:09:39 -06008704{
8705 if (!current->io_uring)
8706 return;
8707 /*
8708 * fput() is pending, will be 2 if the only other ref is our potential
8709 * task file note. If the task is exiting, drop regardless of count.
8710 */
Pavel Begunkovc8fb20b2020-10-22 16:38:27 +01008711 if (fatal_signal_pending(current) || (current->flags & PF_EXITING) ||
8712 atomic_long_read(&file->f_count) == 2)
8713 io_uring_del_task_file(file);
Jens Axboe0f212202020-09-13 13:09:39 -06008714}
8715
8716void __io_uring_files_cancel(struct files_struct *files)
8717{
8718 struct io_uring_task *tctx = current->io_uring;
Matthew Wilcox (Oracle)ce765372020-10-09 13:49:51 +01008719 struct file *file;
8720 unsigned long index;
Jens Axboe0f212202020-09-13 13:09:39 -06008721
8722 /* make sure overflow events are dropped */
Jens Axboefdaf0832020-10-30 09:37:30 -06008723 atomic_inc(&tctx->in_idle);
Jens Axboe0f212202020-09-13 13:09:39 -06008724
Matthew Wilcox (Oracle)ce765372020-10-09 13:49:51 +01008725 xa_for_each(&tctx->xa, index, file) {
8726 struct io_ring_ctx *ctx = file->private_data;
Jens Axboe0f212202020-09-13 13:09:39 -06008727
8728 io_uring_cancel_task_requests(ctx, files);
8729 if (files)
8730 io_uring_del_task_file(file);
Matthew Wilcox (Oracle)ce765372020-10-09 13:49:51 +01008731 }
Jens Axboefdaf0832020-10-30 09:37:30 -06008732
8733 atomic_dec(&tctx->in_idle);
8734}
8735
8736static s64 tctx_inflight(struct io_uring_task *tctx)
8737{
8738 unsigned long index;
8739 struct file *file;
8740 s64 inflight;
8741
8742 inflight = percpu_counter_sum(&tctx->inflight);
8743 if (!tctx->sqpoll)
8744 return inflight;
8745
8746 /*
8747 * If we have SQPOLL rings, then we need to iterate and find them, and
8748 * add the pending count for those.
8749 */
8750 xa_for_each(&tctx->xa, index, file) {
8751 struct io_ring_ctx *ctx = file->private_data;
8752
8753 if (ctx->flags & IORING_SETUP_SQPOLL) {
8754 struct io_uring_task *__tctx = ctx->sqo_task->io_uring;
8755
8756 inflight += percpu_counter_sum(&__tctx->inflight);
8757 }
8758 }
8759
8760 return inflight;
Jens Axboe0f212202020-09-13 13:09:39 -06008761}
8762
Jens Axboe0f212202020-09-13 13:09:39 -06008763/*
8764 * Find any io_uring fd that this task has registered or done IO on, and cancel
8765 * requests.
8766 */
8767void __io_uring_task_cancel(void)
8768{
8769 struct io_uring_task *tctx = current->io_uring;
8770 DEFINE_WAIT(wait);
Jens Axboed8a6df12020-10-15 16:24:45 -06008771 s64 inflight;
Jens Axboe0f212202020-09-13 13:09:39 -06008772
8773 /* make sure overflow events are dropped */
Jens Axboefdaf0832020-10-30 09:37:30 -06008774 atomic_inc(&tctx->in_idle);
Jens Axboe0f212202020-09-13 13:09:39 -06008775
Jens Axboed8a6df12020-10-15 16:24:45 -06008776 do {
Jens Axboe0f212202020-09-13 13:09:39 -06008777 /* read completions before cancelations */
Jens Axboefdaf0832020-10-30 09:37:30 -06008778 inflight = tctx_inflight(tctx);
Jens Axboed8a6df12020-10-15 16:24:45 -06008779 if (!inflight)
8780 break;
Jens Axboe0f212202020-09-13 13:09:39 -06008781 __io_uring_files_cancel(NULL);
8782
8783 prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
8784
8785 /*
8786 * If we've seen completions, retry. This avoids a race where
8787 * a completion comes in before we did prepare_to_wait().
8788 */
Jens Axboefdaf0832020-10-30 09:37:30 -06008789 if (inflight != tctx_inflight(tctx))
Jens Axboe0f212202020-09-13 13:09:39 -06008790 continue;
Jens Axboe0f212202020-09-13 13:09:39 -06008791 schedule();
Jens Axboed8a6df12020-10-15 16:24:45 -06008792 } while (1);
Jens Axboe0f212202020-09-13 13:09:39 -06008793
8794 finish_wait(&tctx->wait, &wait);
Jens Axboefdaf0832020-10-30 09:37:30 -06008795 atomic_dec(&tctx->in_idle);
Jens Axboefcb323c2019-10-24 12:39:47 -06008796}
8797
8798static int io_uring_flush(struct file *file, void *data)
8799{
Pavel Begunkovc8fb20b2020-10-22 16:38:27 +01008800 io_uring_attempt_task_drop(file);
Jens Axboefcb323c2019-10-24 12:39:47 -06008801 return 0;
8802}
8803
Roman Penyaev6c5c2402019-11-28 12:53:22 +01008804static void *io_uring_validate_mmap_request(struct file *file,
8805 loff_t pgoff, size_t sz)
Jens Axboe2b188cc2019-01-07 10:46:33 -07008806{
Jens Axboe2b188cc2019-01-07 10:46:33 -07008807 struct io_ring_ctx *ctx = file->private_data;
Roman Penyaev6c5c2402019-11-28 12:53:22 +01008808 loff_t offset = pgoff << PAGE_SHIFT;
Jens Axboe2b188cc2019-01-07 10:46:33 -07008809 struct page *page;
8810 void *ptr;
8811
8812 switch (offset) {
8813 case IORING_OFF_SQ_RING:
Hristo Venev75b28af2019-08-26 17:23:46 +00008814 case IORING_OFF_CQ_RING:
8815 ptr = ctx->rings;
Jens Axboe2b188cc2019-01-07 10:46:33 -07008816 break;
8817 case IORING_OFF_SQES:
8818 ptr = ctx->sq_sqes;
8819 break;
Jens Axboe2b188cc2019-01-07 10:46:33 -07008820 default:
Roman Penyaev6c5c2402019-11-28 12:53:22 +01008821 return ERR_PTR(-EINVAL);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008822 }
8823
8824 page = virt_to_head_page(ptr);
Matthew Wilcox (Oracle)a50b8542019-09-23 15:34:25 -07008825 if (sz > page_size(page))
Roman Penyaev6c5c2402019-11-28 12:53:22 +01008826 return ERR_PTR(-EINVAL);
8827
8828 return ptr;
8829}
8830
8831#ifdef CONFIG_MMU
8832
8833static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
8834{
8835 size_t sz = vma->vm_end - vma->vm_start;
8836 unsigned long pfn;
8837 void *ptr;
8838
8839 ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
8840 if (IS_ERR(ptr))
8841 return PTR_ERR(ptr);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008842
8843 pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
8844 return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
8845}
8846
Roman Penyaev6c5c2402019-11-28 12:53:22 +01008847#else /* !CONFIG_MMU */
8848
8849static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
8850{
8851 return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
8852}
8853
8854static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
8855{
8856 return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
8857}
8858
8859static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
8860 unsigned long addr, unsigned long len,
8861 unsigned long pgoff, unsigned long flags)
8862{
8863 void *ptr;
8864
8865 ptr = io_uring_validate_mmap_request(file, pgoff, len);
8866 if (IS_ERR(ptr))
8867 return PTR_ERR(ptr);
8868
8869 return (unsigned long) ptr;
8870}
8871
8872#endif /* !CONFIG_MMU */
8873
Jens Axboe90554202020-09-03 12:12:41 -06008874static void io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
8875{
8876 DEFINE_WAIT(wait);
8877
8878 do {
8879 if (!io_sqring_full(ctx))
8880 break;
8881
8882 prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
8883
8884 if (!io_sqring_full(ctx))
8885 break;
8886
8887 schedule();
8888 } while (!signal_pending(current));
8889
8890 finish_wait(&ctx->sqo_sq_wait, &wait);
8891}
8892
Jens Axboe2b188cc2019-01-07 10:46:33 -07008893SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
8894 u32, min_complete, u32, flags, const sigset_t __user *, sig,
8895 size_t, sigsz)
8896{
8897 struct io_ring_ctx *ctx;
8898 long ret = -EBADF;
8899 int submitted = 0;
8900 struct fd f;
8901
Jens Axboe4c6e2772020-07-01 11:29:10 -06008902 io_run_task_work();
Jens Axboeb41e9852020-02-17 09:52:41 -07008903
Jens Axboe90554202020-09-03 12:12:41 -06008904 if (flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
8905 IORING_ENTER_SQ_WAIT))
Jens Axboe2b188cc2019-01-07 10:46:33 -07008906 return -EINVAL;
8907
8908 f = fdget(fd);
8909 if (!f.file)
8910 return -EBADF;
8911
8912 ret = -EOPNOTSUPP;
8913 if (f.file->f_op != &io_uring_fops)
8914 goto out_fput;
8915
8916 ret = -ENXIO;
8917 ctx = f.file->private_data;
8918 if (!percpu_ref_tryget(&ctx->refs))
8919 goto out_fput;
8920
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02008921 ret = -EBADFD;
8922 if (ctx->flags & IORING_SETUP_R_DISABLED)
8923 goto out;
8924
Jens Axboe6c271ce2019-01-10 11:22:30 -07008925 /*
8926 * For SQ polling, the thread will do all submissions and completions.
8927 * Just return the requested submit count, and wake the thread if
8928 * we were asked to.
8929 */
Jens Axboeb2a9ead2019-09-12 14:19:16 -06008930 ret = 0;
Jens Axboe6c271ce2019-01-10 11:22:30 -07008931 if (ctx->flags & IORING_SETUP_SQPOLL) {
Jens Axboec1edbf52019-11-10 16:56:04 -07008932 if (!list_empty_careful(&ctx->cq_overflow_list))
Jens Axboee6c8aa92020-09-28 13:10:13 -06008933 io_cqring_overflow_flush(ctx, false, NULL, NULL);
Jens Axboe6c271ce2019-01-10 11:22:30 -07008934 if (flags & IORING_ENTER_SQ_WAKEUP)
Jens Axboe534ca6d2020-09-02 13:52:19 -06008935 wake_up(&ctx->sq_data->wait);
Jens Axboe90554202020-09-03 12:12:41 -06008936 if (flags & IORING_ENTER_SQ_WAIT)
8937 io_sqpoll_wait_sq(ctx);
Jens Axboe6c271ce2019-01-10 11:22:30 -07008938 submitted = to_submit;
Jens Axboeb2a9ead2019-09-12 14:19:16 -06008939 } else if (to_submit) {
Jens Axboefdaf0832020-10-30 09:37:30 -06008940 ret = io_uring_add_task_file(ctx, f.file);
Jens Axboe0f212202020-09-13 13:09:39 -06008941 if (unlikely(ret))
8942 goto out;
Jens Axboe2b188cc2019-01-07 10:46:33 -07008943 mutex_lock(&ctx->uring_lock);
Jens Axboe0f212202020-09-13 13:09:39 -06008944 submitted = io_submit_sqes(ctx, to_submit);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008945 mutex_unlock(&ctx->uring_lock);
Pavel Begunkov7c504e652019-12-18 19:53:45 +03008946
8947 if (submitted != to_submit)
8948 goto out;
Jens Axboe2b188cc2019-01-07 10:46:33 -07008949 }
8950 if (flags & IORING_ENTER_GETEVENTS) {
8951 min_complete = min(min_complete, ctx->cq_entries);
8952
Xiaoguang Wang32b22442020-03-11 09:26:09 +08008953 /*
8954 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
8955 * space applications don't need to do io completion events
8956 * polling again, they can rely on io_sq_thread to do polling
8957 * work, which can reduce cpu usage and uring_lock contention.
8958 */
8959 if (ctx->flags & IORING_SETUP_IOPOLL &&
8960 !(ctx->flags & IORING_SETUP_SQPOLL)) {
Pavel Begunkov7668b922020-07-07 16:36:21 +03008961 ret = io_iopoll_check(ctx, min_complete);
Jens Axboedef596e2019-01-09 08:59:42 -07008962 } else {
8963 ret = io_cqring_wait(ctx, min_complete, sig, sigsz);
8964 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07008965 }
8966
Pavel Begunkov7c504e652019-12-18 19:53:45 +03008967out:
Pavel Begunkov6805b322019-10-08 02:18:42 +03008968 percpu_ref_put(&ctx->refs);
Jens Axboe2b188cc2019-01-07 10:46:33 -07008969out_fput:
8970 fdput(f);
8971 return submitted ? submitted : ret;
8972}
8973
Tobias Klauserbebdb652020-02-26 18:38:32 +01008974#ifdef CONFIG_PROC_FS
Jens Axboe87ce9552020-01-30 08:25:34 -07008975static int io_uring_show_cred(int id, void *p, void *data)
8976{
Jens Axboe6b47ab82020-11-05 09:50:16 -07008977 struct io_identity *iod = p;
8978 const struct cred *cred = iod->creds;
Jens Axboe87ce9552020-01-30 08:25:34 -07008979 struct seq_file *m = data;
8980 struct user_namespace *uns = seq_user_ns(m);
8981 struct group_info *gi;
8982 kernel_cap_t cap;
8983 unsigned __capi;
8984 int g;
8985
8986 seq_printf(m, "%5d\n", id);
8987 seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
8988 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
8989 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
8990 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
8991 seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
8992 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
8993 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
8994 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
8995 seq_puts(m, "\n\tGroups:\t");
8996 gi = cred->group_info;
8997 for (g = 0; g < gi->ngroups; g++) {
8998 seq_put_decimal_ull(m, g ? " " : "",
8999 from_kgid_munged(uns, gi->gid[g]));
9000 }
9001 seq_puts(m, "\n\tCapEff:\t");
9002 cap = cred->cap_effective;
9003 CAP_FOR_EACH_U32(__capi)
9004 seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
9005 seq_putc(m, '\n');
9006 return 0;
9007}
9008
9009static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
9010{
Joseph Qidbbe9c62020-09-29 09:01:22 -06009011 struct io_sq_data *sq = NULL;
Jens Axboefad8e0d2020-09-28 08:57:48 -06009012 bool has_lock;
Jens Axboe87ce9552020-01-30 08:25:34 -07009013 int i;
9014
Jens Axboefad8e0d2020-09-28 08:57:48 -06009015 /*
9016 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9017 * since fdinfo case grabs it in the opposite direction of normal use
9018 * cases. If we fail to get the lock, we just don't iterate any
9019 * structures that could be going away outside the io_uring mutex.
9020 */
9021 has_lock = mutex_trylock(&ctx->uring_lock);
9022
Joseph Qidbbe9c62020-09-29 09:01:22 -06009023 if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL))
9024 sq = ctx->sq_data;
9025
9026 seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
9027 seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
Jens Axboe87ce9552020-01-30 08:25:34 -07009028 seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
Jens Axboefad8e0d2020-09-28 08:57:48 -06009029 for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
Jens Axboe87ce9552020-01-30 08:25:34 -07009030 struct fixed_file_table *table;
9031 struct file *f;
9032
9033 table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT];
9034 f = table->files[i & IORING_FILE_TABLE_MASK];
9035 if (f)
9036 seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
9037 else
9038 seq_printf(m, "%5u: <none>\n", i);
9039 }
9040 seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
Jens Axboefad8e0d2020-09-28 08:57:48 -06009041 for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
Jens Axboe87ce9552020-01-30 08:25:34 -07009042 struct io_mapped_ubuf *buf = &ctx->user_bufs[i];
9043
9044 seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf,
9045 (unsigned int) buf->len);
9046 }
Jens Axboefad8e0d2020-09-28 08:57:48 -06009047 if (has_lock && !idr_is_empty(&ctx->personality_idr)) {
Jens Axboe87ce9552020-01-30 08:25:34 -07009048 seq_printf(m, "Personalities:\n");
9049 idr_for_each(&ctx->personality_idr, io_uring_show_cred, m);
9050 }
Jens Axboed7718a92020-02-14 22:23:12 -07009051 seq_printf(m, "PollList:\n");
9052 spin_lock_irq(&ctx->completion_lock);
9053 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
9054 struct hlist_head *list = &ctx->cancel_hash[i];
9055 struct io_kiocb *req;
9056
9057 hlist_for_each_entry(req, list, hash_node)
9058 seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
9059 req->task->task_works != NULL);
9060 }
9061 spin_unlock_irq(&ctx->completion_lock);
Jens Axboefad8e0d2020-09-28 08:57:48 -06009062 if (has_lock)
9063 mutex_unlock(&ctx->uring_lock);
Jens Axboe87ce9552020-01-30 08:25:34 -07009064}
9065
9066static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
9067{
9068 struct io_ring_ctx *ctx = f->private_data;
9069
9070 if (percpu_ref_tryget(&ctx->refs)) {
9071 __io_uring_show_fdinfo(ctx, m);
9072 percpu_ref_put(&ctx->refs);
9073 }
9074}
Tobias Klauserbebdb652020-02-26 18:38:32 +01009075#endif
Jens Axboe87ce9552020-01-30 08:25:34 -07009076
Jens Axboe2b188cc2019-01-07 10:46:33 -07009077static const struct file_operations io_uring_fops = {
9078 .release = io_uring_release,
Jens Axboefcb323c2019-10-24 12:39:47 -06009079 .flush = io_uring_flush,
Jens Axboe2b188cc2019-01-07 10:46:33 -07009080 .mmap = io_uring_mmap,
Roman Penyaev6c5c2402019-11-28 12:53:22 +01009081#ifndef CONFIG_MMU
9082 .get_unmapped_area = io_uring_nommu_get_unmapped_area,
9083 .mmap_capabilities = io_uring_nommu_mmap_capabilities,
9084#endif
Jens Axboe2b188cc2019-01-07 10:46:33 -07009085 .poll = io_uring_poll,
9086 .fasync = io_uring_fasync,
Tobias Klauserbebdb652020-02-26 18:38:32 +01009087#ifdef CONFIG_PROC_FS
Jens Axboe87ce9552020-01-30 08:25:34 -07009088 .show_fdinfo = io_uring_show_fdinfo,
Tobias Klauserbebdb652020-02-26 18:38:32 +01009089#endif
Jens Axboe2b188cc2019-01-07 10:46:33 -07009090};
9091
9092static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
9093 struct io_uring_params *p)
9094{
Hristo Venev75b28af2019-08-26 17:23:46 +00009095 struct io_rings *rings;
9096 size_t size, sq_array_offset;
Jens Axboe2b188cc2019-01-07 10:46:33 -07009097
Jens Axboebd740482020-08-05 12:58:23 -06009098 /* make sure these are sane, as we already accounted them */
9099 ctx->sq_entries = p->sq_entries;
9100 ctx->cq_entries = p->cq_entries;
9101
Hristo Venev75b28af2019-08-26 17:23:46 +00009102 size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
9103 if (size == SIZE_MAX)
9104 return -EOVERFLOW;
9105
9106 rings = io_mem_alloc(size);
9107 if (!rings)
Jens Axboe2b188cc2019-01-07 10:46:33 -07009108 return -ENOMEM;
9109
Hristo Venev75b28af2019-08-26 17:23:46 +00009110 ctx->rings = rings;
9111 ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
9112 rings->sq_ring_mask = p->sq_entries - 1;
9113 rings->cq_ring_mask = p->cq_entries - 1;
9114 rings->sq_ring_entries = p->sq_entries;
9115 rings->cq_ring_entries = p->cq_entries;
9116 ctx->sq_mask = rings->sq_ring_mask;
9117 ctx->cq_mask = rings->cq_ring_mask;
Jens Axboe2b188cc2019-01-07 10:46:33 -07009118
9119 size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
Jens Axboeeb065d32019-11-20 09:26:29 -07009120 if (size == SIZE_MAX) {
9121 io_mem_free(ctx->rings);
9122 ctx->rings = NULL;
Jens Axboe2b188cc2019-01-07 10:46:33 -07009123 return -EOVERFLOW;
Jens Axboeeb065d32019-11-20 09:26:29 -07009124 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07009125
9126 ctx->sq_sqes = io_mem_alloc(size);
Jens Axboeeb065d32019-11-20 09:26:29 -07009127 if (!ctx->sq_sqes) {
9128 io_mem_free(ctx->rings);
9129 ctx->rings = NULL;
Jens Axboe2b188cc2019-01-07 10:46:33 -07009130 return -ENOMEM;
Jens Axboeeb065d32019-11-20 09:26:29 -07009131 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07009132
Jens Axboe2b188cc2019-01-07 10:46:33 -07009133 return 0;
9134}
9135
9136/*
9137 * Allocate an anonymous fd, this is what constitutes the application
9138 * visible backing of an io_uring instance. The application mmaps this
9139 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9140 * we have to tie this fd to a socket for file garbage collection purposes.
9141 */
9142static int io_uring_get_fd(struct io_ring_ctx *ctx)
9143{
9144 struct file *file;
9145 int ret;
9146
9147#if defined(CONFIG_UNIX)
9148 ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
9149 &ctx->ring_sock);
9150 if (ret)
9151 return ret;
9152#endif
9153
9154 ret = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
9155 if (ret < 0)
9156 goto err;
9157
9158 file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
9159 O_RDWR | O_CLOEXEC);
9160 if (IS_ERR(file)) {
Jens Axboe0f212202020-09-13 13:09:39 -06009161err_fd:
Jens Axboe2b188cc2019-01-07 10:46:33 -07009162 put_unused_fd(ret);
9163 ret = PTR_ERR(file);
9164 goto err;
9165 }
9166
9167#if defined(CONFIG_UNIX)
9168 ctx->ring_sock->file = file;
9169#endif
Jens Axboefdaf0832020-10-30 09:37:30 -06009170 if (unlikely(io_uring_add_task_file(ctx, file))) {
Jens Axboe0f212202020-09-13 13:09:39 -06009171 file = ERR_PTR(-ENOMEM);
9172 goto err_fd;
9173 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07009174 fd_install(ret, file);
9175 return ret;
9176err:
9177#if defined(CONFIG_UNIX)
9178 sock_release(ctx->ring_sock);
9179 ctx->ring_sock = NULL;
9180#endif
9181 return ret;
9182}
9183
Xiaoguang Wang7f136572020-05-05 16:28:53 +08009184static int io_uring_create(unsigned entries, struct io_uring_params *p,
9185 struct io_uring_params __user *params)
Jens Axboe2b188cc2019-01-07 10:46:33 -07009186{
9187 struct user_struct *user = NULL;
9188 struct io_ring_ctx *ctx;
Bijan Mottahedehaad5d8d2020-06-16 16:36:08 -07009189 bool limit_mem;
Jens Axboe2b188cc2019-01-07 10:46:33 -07009190 int ret;
9191
Jens Axboe8110c1a2019-12-28 15:39:54 -07009192 if (!entries)
Jens Axboe2b188cc2019-01-07 10:46:33 -07009193 return -EINVAL;
Jens Axboe8110c1a2019-12-28 15:39:54 -07009194 if (entries > IORING_MAX_ENTRIES) {
9195 if (!(p->flags & IORING_SETUP_CLAMP))
9196 return -EINVAL;
9197 entries = IORING_MAX_ENTRIES;
9198 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07009199
9200 /*
9201 * Use twice as many entries for the CQ ring. It's possible for the
9202 * application to drive a higher depth than the size of the SQ ring,
9203 * since the sqes are only used at submission time. This allows for
Jens Axboe33a107f2019-10-04 12:10:03 -06009204 * some flexibility in overcommitting a bit. If the application has
9205 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9206 * of CQ ring entries manually.
Jens Axboe2b188cc2019-01-07 10:46:33 -07009207 */
9208 p->sq_entries = roundup_pow_of_two(entries);
Jens Axboe33a107f2019-10-04 12:10:03 -06009209 if (p->flags & IORING_SETUP_CQSIZE) {
9210 /*
9211 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9212 * to a power-of-two, if it isn't already. We do NOT impose
9213 * any cq vs sq ring sizing.
9214 */
Jens Axboe8110c1a2019-12-28 15:39:54 -07009215 if (p->cq_entries < p->sq_entries)
Jens Axboe33a107f2019-10-04 12:10:03 -06009216 return -EINVAL;
Jens Axboe8110c1a2019-12-28 15:39:54 -07009217 if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
9218 if (!(p->flags & IORING_SETUP_CLAMP))
9219 return -EINVAL;
9220 p->cq_entries = IORING_MAX_CQ_ENTRIES;
9221 }
Jens Axboe33a107f2019-10-04 12:10:03 -06009222 p->cq_entries = roundup_pow_of_two(p->cq_entries);
9223 } else {
9224 p->cq_entries = 2 * p->sq_entries;
9225 }
Jens Axboe2b188cc2019-01-07 10:46:33 -07009226
9227 user = get_uid(current_user());
Bijan Mottahedehaad5d8d2020-06-16 16:36:08 -07009228 limit_mem = !capable(CAP_IPC_LOCK);
Jens Axboe2b188cc2019-01-07 10:46:33 -07009229
Bijan Mottahedehaad5d8d2020-06-16 16:36:08 -07009230 if (limit_mem) {
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07009231 ret = __io_account_mem(user,
Jens Axboe2b188cc2019-01-07 10:46:33 -07009232 ring_pages(p->sq_entries, p->cq_entries));
9233 if (ret) {
9234 free_uid(user);
9235 return ret;
9236 }
9237 }
9238
9239 ctx = io_ring_ctx_alloc(p);
9240 if (!ctx) {
Bijan Mottahedehaad5d8d2020-06-16 16:36:08 -07009241 if (limit_mem)
Bijan Mottahedeha087e2b2020-06-16 16:36:07 -07009242 __io_unaccount_mem(user, ring_pages(p->sq_entries,
Jens Axboe2b188cc2019-01-07 10:46:33 -07009243 p->cq_entries));
9244 free_uid(user);
9245 return -ENOMEM;
9246 }
9247 ctx->compat = in_compat_syscall();
Jens Axboe2b188cc2019-01-07 10:46:33 -07009248 ctx->user = user;
Jens Axboe0b8c0ec2019-12-02 08:50:00 -07009249 ctx->creds = get_current_cred();
Jens Axboe4ea33a92020-10-15 13:46:44 -06009250#ifdef CONFIG_AUDIT
9251 ctx->loginuid = current->loginuid;
9252 ctx->sessionid = current->sessionid;
9253#endif
Jens Axboe2aede0e2020-09-14 10:45:53 -06009254 ctx->sqo_task = get_task_struct(current);
9255
9256 /*
9257 * This is just grabbed for accounting purposes. When a process exits,
9258 * the mm is exited and dropped before the files, hence we need to hang
9259 * on to this mm purely for the purposes of being able to unaccount
9260 * memory (locked/pinned vm). It's not used for anything else.
9261 */
Jens Axboe6b7898e2020-08-25 07:58:00 -06009262 mmgrab(current->mm);
Jens Axboe2aede0e2020-09-14 10:45:53 -06009263 ctx->mm_account = current->mm;
Jens Axboe6b7898e2020-08-25 07:58:00 -06009264
Dennis Zhou91d8f512020-09-16 13:41:05 -07009265#ifdef CONFIG_BLK_CGROUP
9266 /*
9267 * The sq thread will belong to the original cgroup it was inited in.
9268 * If the cgroup goes offline (e.g. disabling the io controller), then
9269 * issued bios will be associated with the closest cgroup later in the
9270 * block layer.
9271 */
9272 rcu_read_lock();
9273 ctx->sqo_blkcg_css = blkcg_css();
9274 ret = css_tryget_online(ctx->sqo_blkcg_css);
9275 rcu_read_unlock();
9276 if (!ret) {
9277 /* don't init against a dying cgroup, have the user try again */
9278 ctx->sqo_blkcg_css = NULL;
9279 ret = -ENODEV;
9280 goto err;
9281 }
9282#endif
Jens Axboe6c271ce2019-01-10 11:22:30 -07009283
Jens Axboe2b188cc2019-01-07 10:46:33 -07009284 /*
9285 * Account memory _before_ installing the file descriptor. Once
9286 * the descriptor is installed, it can get closed at any time. Also
Jens Axboe2b188cc2019-01-07 10:46:33 -07009287 * do this before hitting the general error path, as ring freeing
Hristo Venev75b28af2019-08-26 17:23:46 +00009288 * will un-account as well.
9289 */
9290 io_account_mem(ctx, ring_pages(p->sq_entries, p->cq_entries),
9291 ACCT_LOCKED);
9292 ctx->limit_mem = limit_mem;
9293
9294 ret = io_allocate_scq_urings(ctx, p);
Jens Axboe2b188cc2019-01-07 10:46:33 -07009295 if (ret)
9296 goto err;
Hristo Venev75b28af2019-08-26 17:23:46 +00009297
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02009298 ret = io_sq_offload_create(ctx, p);
Jens Axboe2b188cc2019-01-07 10:46:33 -07009299 if (ret)
9300 goto err;
9301
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02009302 if (!(p->flags & IORING_SETUP_R_DISABLED))
9303 io_sq_offload_start(ctx);
9304
Jens Axboe2b188cc2019-01-07 10:46:33 -07009305 memset(&p->sq_off, 0, sizeof(p->sq_off));
9306 p->sq_off.head = offsetof(struct io_rings, sq.head);
9307 p->sq_off.tail = offsetof(struct io_rings, sq.tail);
9308 p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
9309 p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
9310 p->sq_off.flags = offsetof(struct io_rings, sq_flags);
9311 p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
9312 p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
9313
9314 memset(&p->cq_off, 0, sizeof(p->cq_off));
Hristo Venev75b28af2019-08-26 17:23:46 +00009315 p->cq_off.head = offsetof(struct io_rings, cq.head);
9316 p->cq_off.tail = offsetof(struct io_rings, cq.tail);
9317 p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
9318 p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
9319 p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
9320 p->cq_off.cqes = offsetof(struct io_rings, cqes);
Stefano Garzarella0d9b5b32020-05-15 18:38:04 +02009321 p->cq_off.flags = offsetof(struct io_rings, cq_flags);
Jens Axboeac90f242019-09-06 10:26:21 -06009322
Xiaoguang Wang7f136572020-05-05 16:28:53 +08009323 p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
9324 IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
Jiufei Xue5769a352020-06-17 17:53:55 +08009325 IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
9326 IORING_FEAT_POLL_32BITS;
Xiaoguang Wang7f136572020-05-05 16:28:53 +08009327
9328 if (copy_to_user(params, p, sizeof(*p))) {
9329 ret = -EFAULT;
9330 goto err;
9331 }
Jens Axboed1719f72020-07-30 13:43:53 -06009332
9333 /*
Jens Axboe044c1ab2019-10-28 09:15:33 -06009334 * Install ring fd as the very last thing, so we don't risk someone
9335 * having closed it before we finish setup
9336 */
9337 ret = io_uring_get_fd(ctx);
9338 if (ret < 0)
9339 goto err;
9340
Dmitrii Dolgovc826bd72019-10-15 19:02:01 +02009341 trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
Jens Axboe2b188cc2019-01-07 10:46:33 -07009342 return ret;
9343err:
9344 io_ring_ctx_wait_and_kill(ctx);
9345 return ret;
9346}
9347
9348/*
9349 * Sets up an aio uring context, and returns the fd. Applications asks for a
9350 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9351 * params structure passed in.
9352 */
9353static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
9354{
9355 struct io_uring_params p;
Jens Axboe2b188cc2019-01-07 10:46:33 -07009356 int i;
9357
9358 if (copy_from_user(&p, params, sizeof(p)))
9359 return -EFAULT;
9360 for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
9361 if (p.resv[i])
9362 return -EINVAL;
9363 }
9364
Jens Axboe6c271ce2019-01-10 11:22:30 -07009365 if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
Jens Axboe8110c1a2019-12-28 15:39:54 -07009366 IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02009367 IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
9368 IORING_SETUP_R_DISABLED))
Jens Axboe2b188cc2019-01-07 10:46:33 -07009369 return -EINVAL;
9370
Xiaoguang Wang7f136572020-05-05 16:28:53 +08009371 return io_uring_create(entries, &p, params);
Jens Axboe2b188cc2019-01-07 10:46:33 -07009372}
9373
9374SYSCALL_DEFINE2(io_uring_setup, u32, entries,
9375 struct io_uring_params __user *, params)
9376{
9377 return io_uring_setup(entries, params);
9378}
9379
Jens Axboe66f4af92020-01-16 15:36:52 -07009380static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
9381{
9382 struct io_uring_probe *p;
9383 size_t size;
9384 int i, ret;
9385
9386 size = struct_size(p, ops, nr_args);
9387 if (size == SIZE_MAX)
9388 return -EOVERFLOW;
9389 p = kzalloc(size, GFP_KERNEL);
9390 if (!p)
9391 return -ENOMEM;
9392
9393 ret = -EFAULT;
9394 if (copy_from_user(p, arg, size))
9395 goto out;
9396 ret = -EINVAL;
9397 if (memchr_inv(p, 0, size))
9398 goto out;
9399
9400 p->last_op = IORING_OP_LAST - 1;
9401 if (nr_args > IORING_OP_LAST)
9402 nr_args = IORING_OP_LAST;
9403
9404 for (i = 0; i < nr_args; i++) {
9405 p->ops[i].op = i;
9406 if (!io_op_defs[i].not_supported)
9407 p->ops[i].flags = IO_URING_OP_SUPPORTED;
9408 }
9409 p->ops_len = i;
9410
9411 ret = 0;
9412 if (copy_to_user(arg, p, size))
9413 ret = -EFAULT;
9414out:
9415 kfree(p);
9416 return ret;
9417}
9418
Jens Axboe071698e2020-01-28 10:04:42 -07009419static int io_register_personality(struct io_ring_ctx *ctx)
9420{
Jens Axboe1e6fa522020-10-15 08:46:24 -06009421 struct io_identity *id;
9422 int ret;
Jens Axboe071698e2020-01-28 10:04:42 -07009423
Jens Axboe1e6fa522020-10-15 08:46:24 -06009424 id = kmalloc(sizeof(*id), GFP_KERNEL);
9425 if (unlikely(!id))
9426 return -ENOMEM;
9427
9428 io_init_identity(id);
9429 id->creds = get_current_cred();
9430
9431 ret = idr_alloc_cyclic(&ctx->personality_idr, id, 1, USHRT_MAX, GFP_KERNEL);
9432 if (ret < 0) {
9433 put_cred(id->creds);
9434 kfree(id);
9435 }
9436 return ret;
Jens Axboe071698e2020-01-28 10:04:42 -07009437}
9438
9439static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
9440{
Jens Axboe1e6fa522020-10-15 08:46:24 -06009441 struct io_identity *iod;
Jens Axboe071698e2020-01-28 10:04:42 -07009442
Jens Axboe1e6fa522020-10-15 08:46:24 -06009443 iod = idr_remove(&ctx->personality_idr, id);
9444 if (iod) {
9445 put_cred(iod->creds);
9446 if (refcount_dec_and_test(&iod->count))
9447 kfree(iod);
Jens Axboe071698e2020-01-28 10:04:42 -07009448 return 0;
9449 }
9450
9451 return -EINVAL;
9452}
9453
Stefano Garzarella21b55db2020-08-27 16:58:30 +02009454static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
9455 unsigned int nr_args)
9456{
9457 struct io_uring_restriction *res;
9458 size_t size;
9459 int i, ret;
9460
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02009461 /* Restrictions allowed only if rings started disabled */
9462 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
9463 return -EBADFD;
9464
Stefano Garzarella21b55db2020-08-27 16:58:30 +02009465 /* We allow only a single restrictions registration */
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02009466 if (ctx->restrictions.registered)
Stefano Garzarella21b55db2020-08-27 16:58:30 +02009467 return -EBUSY;
9468
9469 if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
9470 return -EINVAL;
9471
9472 size = array_size(nr_args, sizeof(*res));
9473 if (size == SIZE_MAX)
9474 return -EOVERFLOW;
9475
9476 res = memdup_user(arg, size);
9477 if (IS_ERR(res))
9478 return PTR_ERR(res);
9479
9480 ret = 0;
9481
9482 for (i = 0; i < nr_args; i++) {
9483 switch (res[i].opcode) {
9484 case IORING_RESTRICTION_REGISTER_OP:
9485 if (res[i].register_op >= IORING_REGISTER_LAST) {
9486 ret = -EINVAL;
9487 goto out;
9488 }
9489
9490 __set_bit(res[i].register_op,
9491 ctx->restrictions.register_op);
9492 break;
9493 case IORING_RESTRICTION_SQE_OP:
9494 if (res[i].sqe_op >= IORING_OP_LAST) {
9495 ret = -EINVAL;
9496 goto out;
9497 }
9498
9499 __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
9500 break;
9501 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
9502 ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
9503 break;
9504 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
9505 ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
9506 break;
9507 default:
9508 ret = -EINVAL;
9509 goto out;
9510 }
9511 }
9512
9513out:
9514 /* Reset all restrictions if an error happened */
9515 if (ret != 0)
9516 memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
9517 else
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02009518 ctx->restrictions.registered = true;
Stefano Garzarella21b55db2020-08-27 16:58:30 +02009519
9520 kfree(res);
9521 return ret;
9522}
9523
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02009524static int io_register_enable_rings(struct io_ring_ctx *ctx)
9525{
9526 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
9527 return -EBADFD;
9528
9529 if (ctx->restrictions.registered)
9530 ctx->restricted = 1;
9531
9532 ctx->flags &= ~IORING_SETUP_R_DISABLED;
9533
9534 io_sq_offload_start(ctx);
9535
9536 return 0;
9537}
9538
Jens Axboe071698e2020-01-28 10:04:42 -07009539static bool io_register_op_must_quiesce(int op)
9540{
9541 switch (op) {
9542 case IORING_UNREGISTER_FILES:
9543 case IORING_REGISTER_FILES_UPDATE:
9544 case IORING_REGISTER_PROBE:
9545 case IORING_REGISTER_PERSONALITY:
9546 case IORING_UNREGISTER_PERSONALITY:
9547 return false;
9548 default:
9549 return true;
9550 }
9551}
9552
Jens Axboeedafcce2019-01-09 09:16:05 -07009553static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
9554 void __user *arg, unsigned nr_args)
Jens Axboeb19062a2019-04-15 10:49:38 -06009555 __releases(ctx->uring_lock)
9556 __acquires(ctx->uring_lock)
Jens Axboeedafcce2019-01-09 09:16:05 -07009557{
9558 int ret;
9559
Jens Axboe35fa71a2019-04-22 10:23:23 -06009560 /*
9561 * We're inside the ring mutex, if the ref is already dying, then
9562 * someone else killed the ctx or is already going through
9563 * io_uring_register().
9564 */
9565 if (percpu_ref_is_dying(&ctx->refs))
9566 return -ENXIO;
9567
Jens Axboe071698e2020-01-28 10:04:42 -07009568 if (io_register_op_must_quiesce(opcode)) {
Jens Axboe05f3fb32019-12-09 11:22:50 -07009569 percpu_ref_kill(&ctx->refs);
Jens Axboeb19062a2019-04-15 10:49:38 -06009570
Jens Axboe05f3fb32019-12-09 11:22:50 -07009571 /*
9572 * Drop uring mutex before waiting for references to exit. If
9573 * another thread is currently inside io_uring_enter() it might
9574 * need to grab the uring_lock to make progress. If we hold it
9575 * here across the drain wait, then we can deadlock. It's safe
9576 * to drop the mutex here, since no new references will come in
9577 * after we've killed the percpu ref.
9578 */
9579 mutex_unlock(&ctx->uring_lock);
Jens Axboeaf9c1a42020-09-24 13:32:18 -06009580 do {
9581 ret = wait_for_completion_interruptible(&ctx->ref_comp);
9582 if (!ret)
9583 break;
Jens Axboeed6930c2020-10-08 19:09:46 -06009584 ret = io_run_task_work_sig();
9585 if (ret < 0)
9586 break;
Jens Axboeaf9c1a42020-09-24 13:32:18 -06009587 } while (1);
9588
Jens Axboe05f3fb32019-12-09 11:22:50 -07009589 mutex_lock(&ctx->uring_lock);
Jens Axboeaf9c1a42020-09-24 13:32:18 -06009590
Jens Axboec1503682020-01-08 08:26:07 -07009591 if (ret) {
9592 percpu_ref_resurrect(&ctx->refs);
Stefano Garzarella21b55db2020-08-27 16:58:30 +02009593 goto out_quiesce;
9594 }
9595 }
9596
9597 if (ctx->restricted) {
9598 if (opcode >= IORING_REGISTER_LAST) {
9599 ret = -EINVAL;
9600 goto out;
9601 }
9602
9603 if (!test_bit(opcode, ctx->restrictions.register_op)) {
9604 ret = -EACCES;
Jens Axboec1503682020-01-08 08:26:07 -07009605 goto out;
9606 }
Jens Axboe05f3fb32019-12-09 11:22:50 -07009607 }
Jens Axboeedafcce2019-01-09 09:16:05 -07009608
9609 switch (opcode) {
9610 case IORING_REGISTER_BUFFERS:
9611 ret = io_sqe_buffer_register(ctx, arg, nr_args);
9612 break;
9613 case IORING_UNREGISTER_BUFFERS:
9614 ret = -EINVAL;
9615 if (arg || nr_args)
9616 break;
9617 ret = io_sqe_buffer_unregister(ctx);
9618 break;
Jens Axboe6b063142019-01-10 22:13:58 -07009619 case IORING_REGISTER_FILES:
9620 ret = io_sqe_files_register(ctx, arg, nr_args);
9621 break;
9622 case IORING_UNREGISTER_FILES:
9623 ret = -EINVAL;
9624 if (arg || nr_args)
9625 break;
9626 ret = io_sqe_files_unregister(ctx);
9627 break;
Jens Axboec3a31e62019-10-03 13:59:56 -06009628 case IORING_REGISTER_FILES_UPDATE:
9629 ret = io_sqe_files_update(ctx, arg, nr_args);
9630 break;
Jens Axboe9b402842019-04-11 11:45:41 -06009631 case IORING_REGISTER_EVENTFD:
Jens Axboef2842ab2020-01-08 11:04:00 -07009632 case IORING_REGISTER_EVENTFD_ASYNC:
Jens Axboe9b402842019-04-11 11:45:41 -06009633 ret = -EINVAL;
9634 if (nr_args != 1)
9635 break;
9636 ret = io_eventfd_register(ctx, arg);
Jens Axboef2842ab2020-01-08 11:04:00 -07009637 if (ret)
9638 break;
9639 if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
9640 ctx->eventfd_async = 1;
9641 else
9642 ctx->eventfd_async = 0;
Jens Axboe9b402842019-04-11 11:45:41 -06009643 break;
9644 case IORING_UNREGISTER_EVENTFD:
9645 ret = -EINVAL;
9646 if (arg || nr_args)
9647 break;
9648 ret = io_eventfd_unregister(ctx);
9649 break;
Jens Axboe66f4af92020-01-16 15:36:52 -07009650 case IORING_REGISTER_PROBE:
9651 ret = -EINVAL;
9652 if (!arg || nr_args > 256)
9653 break;
9654 ret = io_probe(ctx, arg, nr_args);
9655 break;
Jens Axboe071698e2020-01-28 10:04:42 -07009656 case IORING_REGISTER_PERSONALITY:
9657 ret = -EINVAL;
9658 if (arg || nr_args)
9659 break;
9660 ret = io_register_personality(ctx);
9661 break;
9662 case IORING_UNREGISTER_PERSONALITY:
9663 ret = -EINVAL;
9664 if (arg)
9665 break;
9666 ret = io_unregister_personality(ctx, nr_args);
9667 break;
Stefano Garzarella7e84e1c2020-08-27 16:58:31 +02009668 case IORING_REGISTER_ENABLE_RINGS:
9669 ret = -EINVAL;
9670 if (arg || nr_args)
9671 break;
9672 ret = io_register_enable_rings(ctx);
9673 break;
Stefano Garzarella21b55db2020-08-27 16:58:30 +02009674 case IORING_REGISTER_RESTRICTIONS:
9675 ret = io_register_restrictions(ctx, arg, nr_args);
9676 break;
Jens Axboeedafcce2019-01-09 09:16:05 -07009677 default:
9678 ret = -EINVAL;
9679 break;
9680 }
9681
Stefano Garzarella21b55db2020-08-27 16:58:30 +02009682out:
Jens Axboe071698e2020-01-28 10:04:42 -07009683 if (io_register_op_must_quiesce(opcode)) {
Jens Axboe05f3fb32019-12-09 11:22:50 -07009684 /* bring the ctx back to life */
Jens Axboe05f3fb32019-12-09 11:22:50 -07009685 percpu_ref_reinit(&ctx->refs);
Stefano Garzarella21b55db2020-08-27 16:58:30 +02009686out_quiesce:
Jens Axboe0f158b42020-05-14 17:18:39 -06009687 reinit_completion(&ctx->ref_comp);
Jens Axboe05f3fb32019-12-09 11:22:50 -07009688 }
Jens Axboeedafcce2019-01-09 09:16:05 -07009689 return ret;
9690}
9691
9692SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
9693 void __user *, arg, unsigned int, nr_args)
9694{
9695 struct io_ring_ctx *ctx;
9696 long ret = -EBADF;
9697 struct fd f;
9698
9699 f = fdget(fd);
9700 if (!f.file)
9701 return -EBADF;
9702
9703 ret = -EOPNOTSUPP;
9704 if (f.file->f_op != &io_uring_fops)
9705 goto out_fput;
9706
9707 ctx = f.file->private_data;
9708
9709 mutex_lock(&ctx->uring_lock);
9710 ret = __io_uring_register(ctx, opcode, arg, nr_args);
9711 mutex_unlock(&ctx->uring_lock);
Dmitrii Dolgovc826bd72019-10-15 19:02:01 +02009712 trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
9713 ctx->cq_ev_fd != NULL, ret);
Jens Axboeedafcce2019-01-09 09:16:05 -07009714out_fput:
9715 fdput(f);
9716 return ret;
9717}
9718
Jens Axboe2b188cc2019-01-07 10:46:33 -07009719static int __init io_uring_init(void)
9720{
Stefan Metzmacherd7f62e82020-01-29 14:39:41 +01009721#define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
9722 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
9723 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
9724} while (0)
9725
9726#define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
9727 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
9728 BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
9729 BUILD_BUG_SQE_ELEM(0, __u8, opcode);
9730 BUILD_BUG_SQE_ELEM(1, __u8, flags);
9731 BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
9732 BUILD_BUG_SQE_ELEM(4, __s32, fd);
9733 BUILD_BUG_SQE_ELEM(8, __u64, off);
9734 BUILD_BUG_SQE_ELEM(8, __u64, addr2);
9735 BUILD_BUG_SQE_ELEM(16, __u64, addr);
Pavel Begunkov7d67af22020-02-24 11:32:45 +03009736 BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
Stefan Metzmacherd7f62e82020-01-29 14:39:41 +01009737 BUILD_BUG_SQE_ELEM(24, __u32, len);
9738 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
9739 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
9740 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
9741 BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
Jiufei Xue5769a352020-06-17 17:53:55 +08009742 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
9743 BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
Stefan Metzmacherd7f62e82020-01-29 14:39:41 +01009744 BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
9745 BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
9746 BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
9747 BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
9748 BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
9749 BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
9750 BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
9751 BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
Pavel Begunkov7d67af22020-02-24 11:32:45 +03009752 BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
Stefan Metzmacherd7f62e82020-01-29 14:39:41 +01009753 BUILD_BUG_SQE_ELEM(32, __u64, user_data);
9754 BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
9755 BUILD_BUG_SQE_ELEM(42, __u16, personality);
Pavel Begunkov7d67af22020-02-24 11:32:45 +03009756 BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
Stefan Metzmacherd7f62e82020-01-29 14:39:41 +01009757
Jens Axboed3656342019-12-18 09:50:26 -07009758 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
Jens Axboe84557872020-03-03 15:28:17 -07009759 BUILD_BUG_ON(__REQ_F_LAST_BIT >= 8 * sizeof(int));
Jens Axboe2b188cc2019-01-07 10:46:33 -07009760 req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC);
9761 return 0;
9762};
9763__initcall(io_uring_init);