1 // SPDX-License-Identifier: GPL-2.0
3 * Shared application/kernel submission and completion ring pairs, for
4 * supporting fast/efficient IO.
6 * A note on the read/write ordering memory barriers that are matched between
7 * the application and kernel side.
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
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
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
30 * Also see the examples in the liburing library:
32 * git://git.kernel.dk/liburing
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.
39 * Copyright (C) 2018-2019 Jens Axboe
40 * Copyright (c) 2018-2019 Christoph Hellwig
42 #include <linux/kernel.h>
43 #include <linux/init.h>
44 #include <linux/errno.h>
45 #include <linux/syscalls.h>
46 #include <linux/compat.h>
47 #include <net/compat.h>
48 #include <linux/refcount.h>
49 #include <linux/uio.h>
50 #include <linux/bits.h>
52 #include <linux/sched/signal.h>
54 #include <linux/file.h>
55 #include <linux/fdtable.h>
57 #include <linux/mman.h>
58 #include <linux/percpu.h>
59 #include <linux/slab.h>
60 #include <linux/blkdev.h>
61 #include <linux/bvec.h>
62 #include <linux/net.h>
64 #include <net/af_unix.h>
66 #include <linux/anon_inodes.h>
67 #include <linux/sched/mm.h>
68 #include <linux/uaccess.h>
69 #include <linux/nospec.h>
70 #include <linux/sizes.h>
71 #include <linux/hugetlb.h>
72 #include <linux/highmem.h>
73 #include <linux/namei.h>
74 #include <linux/fsnotify.h>
75 #include <linux/fadvise.h>
76 #include <linux/eventpoll.h>
77 #include <linux/splice.h>
78 #include <linux/task_work.h>
79 #include <linux/pagemap.h>
80 #include <linux/io_uring.h>
82 #define CREATE_TRACE_POINTS
83 #include <trace/events/io_uring.h>
85 #include <uapi/linux/io_uring.h>
90 #define IORING_MAX_ENTRIES 32768
91 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
94 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
96 #define IORING_FILE_TABLE_SHIFT 9
97 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
98 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
99 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
100 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
101 IORING_REGISTER_LAST + IORING_OP_LAST)
103 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
104 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
108 u32 head ____cacheline_aligned_in_smp
;
109 u32 tail ____cacheline_aligned_in_smp
;
113 * This data is shared with the application through the mmap at offsets
114 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
116 * The offsets to the member fields are published through struct
117 * io_sqring_offsets when calling io_uring_setup.
121 * Head and tail offsets into the ring; the offsets need to be
122 * masked to get valid indices.
124 * The kernel controls head of the sq ring and the tail of the cq ring,
125 * and the application controls tail of the sq ring and the head of the
128 struct io_uring sq
, cq
;
130 * Bitmasks to apply to head and tail offsets (constant, equals
133 u32 sq_ring_mask
, cq_ring_mask
;
134 /* Ring sizes (constant, power of 2) */
135 u32 sq_ring_entries
, cq_ring_entries
;
137 * Number of invalid entries dropped by the kernel due to
138 * invalid index stored in array
140 * Written by the kernel, shouldn't be modified by the
141 * application (i.e. get number of "new events" by comparing to
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).
152 * Written by the kernel, shouldn't be modified by the
155 * The application needs a full memory barrier before checking
156 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
162 * Written by the application, shouldn't be modified by the
167 * Number of completion events lost because the queue was full;
168 * this should be avoided by the application by making sure
169 * there are not more requests pending than there is space in
170 * the completion queue.
172 * Written by the kernel, shouldn't be modified by the
173 * application (i.e. get number of "new events" by comparing to
176 * As completion events come in out of order this counter is not
177 * ordered with any other data.
181 * Ring buffer of completion events.
183 * The kernel writes completion events fresh every time they are
184 * produced, so the application is allowed to modify pending
187 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
190 enum io_uring_cmd_flags
{
191 IO_URING_F_NONBLOCK
= 1,
192 IO_URING_F_COMPLETE_DEFER
= 2,
195 struct io_mapped_ubuf
{
198 struct bio_vec
*bvec
;
199 unsigned int nr_bvecs
;
200 unsigned long acct_pages
;
205 struct io_overflow_cqe
{
206 struct io_uring_cqe cqe
;
207 struct list_head list
;
211 struct list_head list
;
218 struct fixed_rsrc_table
{
222 struct io_rsrc_node
{
223 struct percpu_ref refs
;
224 struct list_head node
;
225 struct list_head rsrc_list
;
226 struct io_rsrc_data
*rsrc_data
;
227 void (*rsrc_put
)(struct io_ring_ctx
*ctx
,
228 struct io_rsrc_put
*prsrc
);
229 struct llist_node llist
;
233 struct io_rsrc_data
{
234 struct fixed_rsrc_table
*table
;
235 struct io_ring_ctx
*ctx
;
237 struct io_rsrc_node
*node
;
238 struct percpu_ref refs
;
239 struct completion done
;
244 struct list_head list
;
250 struct io_restriction
{
251 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
252 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
253 u8 sqe_flags_allowed
;
254 u8 sqe_flags_required
;
259 IO_SQ_THREAD_SHOULD_STOP
= 0,
260 IO_SQ_THREAD_SHOULD_PARK
,
265 atomic_t park_pending
;
268 /* ctx's that are using this sqd */
269 struct list_head ctx_list
;
271 struct task_struct
*thread
;
272 struct wait_queue_head wait
;
274 unsigned sq_thread_idle
;
280 struct completion exited
;
281 struct callback_head
*park_task_work
;
284 #define IO_IOPOLL_BATCH 8
285 #define IO_COMPL_BATCH 32
286 #define IO_REQ_CACHE_SIZE 32
287 #define IO_REQ_ALLOC_BATCH 8
289 struct io_comp_state
{
290 struct io_kiocb
*reqs
[IO_COMPL_BATCH
];
292 unsigned int locked_free_nr
;
293 /* inline/task_work completion list, under ->uring_lock */
294 struct list_head free_list
;
295 /* IRQ completion list, under ->completion_lock */
296 struct list_head locked_free_list
;
299 struct io_submit_link
{
300 struct io_kiocb
*head
;
301 struct io_kiocb
*last
;
304 struct io_submit_state
{
305 struct blk_plug plug
;
306 struct io_submit_link link
;
309 * io_kiocb alloc cache
311 void *reqs
[IO_REQ_CACHE_SIZE
];
312 unsigned int free_reqs
;
317 * Batch completion logic
319 struct io_comp_state comp
;
322 * File reference cache
326 unsigned int file_refs
;
327 unsigned int ios_left
;
332 struct percpu_ref refs
;
333 } ____cacheline_aligned_in_smp
;
337 unsigned int compat
: 1;
338 unsigned int cq_overflow_flushed
: 1;
339 unsigned int drain_next
: 1;
340 unsigned int eventfd_async
: 1;
341 unsigned int restricted
: 1;
344 * Ring buffer of indices into array of io_uring_sqe, which is
345 * mmapped by the application using the IORING_OFF_SQES offset.
347 * This indirection could e.g. be used to assign fixed
348 * io_uring_sqe entries to operations and only submit them to
349 * the queue when needed.
351 * The kernel modifies neither the indices array nor the entries
355 unsigned cached_sq_head
;
358 unsigned sq_thread_idle
;
359 unsigned cached_sq_dropped
;
360 unsigned cached_cq_overflow
;
361 unsigned long sq_check_overflow
;
363 /* hashed buffered write serialization */
364 struct io_wq_hash
*hash_map
;
366 struct list_head defer_list
;
367 struct list_head timeout_list
;
368 struct list_head cq_overflow_list
;
370 struct io_uring_sqe
*sq_sqes
;
371 } ____cacheline_aligned_in_smp
;
374 struct mutex uring_lock
;
375 wait_queue_head_t wait
;
376 } ____cacheline_aligned_in_smp
;
378 struct io_submit_state submit_state
;
380 struct io_rings
*rings
;
382 /* Only used for accounting purposes */
383 struct mm_struct
*mm_account
;
385 const struct cred
*sq_creds
; /* cred used for __io_sq_thread() */
386 struct io_sq_data
*sq_data
; /* if using sq thread polling */
388 struct wait_queue_head sqo_sq_wait
;
389 struct list_head sqd_list
;
392 * If used, fixed file set. Writers must ensure that ->refs is dead,
393 * readers must ensure that ->refs is alive as long as the file* is
394 * used. Only updated through io_uring_register(2).
396 struct io_rsrc_data
*file_data
;
397 unsigned nr_user_files
;
399 /* if used, fixed mapped user buffers */
400 unsigned nr_user_bufs
;
401 struct io_mapped_ubuf
*user_bufs
;
403 struct user_struct
*user
;
405 struct completion ref_comp
;
407 #if defined(CONFIG_UNIX)
408 struct socket
*ring_sock
;
411 struct xarray io_buffers
;
413 struct xarray personalities
;
417 unsigned cached_cq_tail
;
420 atomic_t cq_timeouts
;
421 unsigned cq_last_tm_flush
;
422 unsigned long cq_check_overflow
;
423 struct wait_queue_head cq_wait
;
424 struct fasync_struct
*cq_fasync
;
425 struct eventfd_ctx
*cq_ev_fd
;
426 } ____cacheline_aligned_in_smp
;
429 spinlock_t completion_lock
;
432 * ->iopoll_list is protected by the ctx->uring_lock for
433 * io_uring instances that don't use IORING_SETUP_SQPOLL.
434 * For SQPOLL, only the single threaded io_sq_thread() will
435 * manipulate the list, hence no extra locking is needed there.
437 struct list_head iopoll_list
;
438 struct hlist_head
*cancel_hash
;
439 unsigned cancel_hash_bits
;
440 bool poll_multi_file
;
442 spinlock_t inflight_lock
;
443 struct list_head inflight_list
;
444 } ____cacheline_aligned_in_smp
;
446 struct delayed_work rsrc_put_work
;
447 struct llist_head rsrc_put_llist
;
448 struct list_head rsrc_ref_list
;
449 spinlock_t rsrc_ref_lock
;
450 struct io_rsrc_node
*rsrc_backup_node
;
452 struct io_restriction restrictions
;
455 struct callback_head
*exit_task_work
;
457 struct wait_queue_head hash_wait
;
459 /* Keep this last, we don't need it for the fast path */
460 struct work_struct exit_work
;
461 struct list_head tctx_list
;
464 struct io_uring_task
{
465 /* submission side */
467 struct wait_queue_head wait
;
468 const struct io_ring_ctx
*last
;
470 struct percpu_counter inflight
;
473 spinlock_t task_lock
;
474 struct io_wq_work_list task_list
;
475 unsigned long task_state
;
476 struct callback_head task_work
;
480 * First field must be the file pointer in all the
481 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
483 struct io_poll_iocb
{
485 struct wait_queue_head
*head
;
490 bool update_user_data
;
492 struct wait_queue_entry wait
;
500 struct io_poll_remove
{
510 struct io_timeout_data
{
511 struct io_kiocb
*req
;
512 struct hrtimer timer
;
513 struct timespec64 ts
;
514 enum hrtimer_mode mode
;
519 struct sockaddr __user
*addr
;
520 int __user
*addr_len
;
522 unsigned long nofile
;
542 struct list_head list
;
543 /* head of the link, used by linked timeouts only */
544 struct io_kiocb
*head
;
547 struct io_timeout_rem
{
552 struct timespec64 ts
;
557 /* NOTE: kiocb has the file as the first member, so don't do it here */
565 struct sockaddr __user
*addr
;
572 struct user_msghdr __user
*umsg
;
578 struct io_buffer
*kbuf
;
584 struct filename
*filename
;
586 unsigned long nofile
;
589 struct io_rsrc_update
{
615 struct epoll_event event
;
619 struct file
*file_out
;
620 struct file
*file_in
;
627 struct io_provide_buf
{
641 const char __user
*filename
;
642 struct statx __user
*buffer
;
654 struct filename
*oldpath
;
655 struct filename
*newpath
;
663 struct filename
*filename
;
666 struct io_completion
{
668 struct list_head list
;
672 struct io_async_connect
{
673 struct sockaddr_storage address
;
676 struct io_async_msghdr
{
677 struct iovec fast_iov
[UIO_FASTIOV
];
678 /* points to an allocated iov, if NULL we use fast_iov instead */
679 struct iovec
*free_iov
;
680 struct sockaddr __user
*uaddr
;
682 struct sockaddr_storage addr
;
686 struct iovec fast_iov
[UIO_FASTIOV
];
687 const struct iovec
*free_iovec
;
688 struct iov_iter iter
;
690 struct wait_page_queue wpq
;
694 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
695 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
696 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
697 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
698 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
699 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
705 REQ_F_LINK_TIMEOUT_BIT
,
706 REQ_F_NEED_CLEANUP_BIT
,
708 REQ_F_BUFFER_SELECTED_BIT
,
709 REQ_F_LTIMEOUT_ACTIVE_BIT
,
710 REQ_F_COMPLETE_INLINE_BIT
,
712 REQ_F_DONT_REISSUE_BIT
,
713 /* keep async read/write and isreg together and in order */
714 REQ_F_ASYNC_READ_BIT
,
715 REQ_F_ASYNC_WRITE_BIT
,
718 /* not a real bit, just to check we're not overflowing the space */
724 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
725 /* drain existing IO first */
726 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
728 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
729 /* doesn't sever on completion < 0 */
730 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
732 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
733 /* IOSQE_BUFFER_SELECT */
734 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
736 /* fail rest of links */
737 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
738 /* on inflight list, should be cancelled and waited on exit reliably */
739 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
740 /* read/write uses file position */
741 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
742 /* must not punt to workers */
743 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
744 /* has or had linked timeout */
745 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
747 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
748 /* already went through poll handler */
749 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
750 /* buffer already selected */
751 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
752 /* linked timeout is active, i.e. prepared by link's head */
753 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
754 /* completion is deferred through io_comp_state */
755 REQ_F_COMPLETE_INLINE
= BIT(REQ_F_COMPLETE_INLINE_BIT
),
756 /* caller should reissue async */
757 REQ_F_REISSUE
= BIT(REQ_F_REISSUE_BIT
),
758 /* don't attempt request reissue, see io_rw_reissue() */
759 REQ_F_DONT_REISSUE
= BIT(REQ_F_DONT_REISSUE_BIT
),
760 /* supports async reads */
761 REQ_F_ASYNC_READ
= BIT(REQ_F_ASYNC_READ_BIT
),
762 /* supports async writes */
763 REQ_F_ASYNC_WRITE
= BIT(REQ_F_ASYNC_WRITE_BIT
),
765 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
769 struct io_poll_iocb poll
;
770 struct io_poll_iocb
*double_poll
;
773 struct io_task_work
{
774 struct io_wq_work_node node
;
775 task_work_func_t func
;
779 * NOTE! Each of the iocb union members has the file pointer
780 * as the first entry in their struct definition. So you can
781 * access the file pointer through any of the sub-structs,
782 * or directly as just 'ki_filp' in this struct.
788 struct io_poll_iocb poll
;
789 struct io_poll_remove poll_remove
;
790 struct io_accept accept
;
792 struct io_cancel cancel
;
793 struct io_timeout timeout
;
794 struct io_timeout_rem timeout_rem
;
795 struct io_connect connect
;
796 struct io_sr_msg sr_msg
;
798 struct io_close close
;
799 struct io_rsrc_update rsrc_update
;
800 struct io_fadvise fadvise
;
801 struct io_madvise madvise
;
802 struct io_epoll epoll
;
803 struct io_splice splice
;
804 struct io_provide_buf pbuf
;
805 struct io_statx statx
;
806 struct io_shutdown shutdown
;
807 struct io_rename rename
;
808 struct io_unlink unlink
;
809 /* use only after cleaning per-op data, see io_clean_op() */
810 struct io_completion
compl;
813 /* opcode allocated if it needs to store data for async defer */
816 /* polled IO has completed */
822 struct io_ring_ctx
*ctx
;
825 struct task_struct
*task
;
828 struct io_kiocb
*link
;
829 struct percpu_ref
*fixed_rsrc_refs
;
832 * 1. used with ctx->iopoll_list with reads/writes
833 * 2. to track reqs with ->files (see io_op_def::file_table)
835 struct list_head inflight_entry
;
837 struct io_task_work io_task_work
;
838 struct callback_head task_work
;
840 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
841 struct hlist_node hash_node
;
842 struct async_poll
*apoll
;
843 struct io_wq_work work
;
846 struct io_tctx_node
{
847 struct list_head ctx_node
;
848 struct task_struct
*task
;
849 struct io_ring_ctx
*ctx
;
852 struct io_defer_entry
{
853 struct list_head list
;
854 struct io_kiocb
*req
;
859 /* needs req->file assigned */
860 unsigned needs_file
: 1;
861 /* hash wq insertion if file is a regular file */
862 unsigned hash_reg_file
: 1;
863 /* unbound wq insertion if file is a non-regular file */
864 unsigned unbound_nonreg_file
: 1;
865 /* opcode is not supported by this kernel */
866 unsigned not_supported
: 1;
867 /* set if opcode supports polled "wait" */
869 unsigned pollout
: 1;
870 /* op supports buffer selection */
871 unsigned buffer_select
: 1;
872 /* do prep async if is going to be punted */
873 unsigned needs_async_setup
: 1;
874 /* should block plug */
876 /* size of async data needed, if any */
877 unsigned short async_size
;
880 static const struct io_op_def io_op_defs
[] = {
881 [IORING_OP_NOP
] = {},
882 [IORING_OP_READV
] = {
884 .unbound_nonreg_file
= 1,
887 .needs_async_setup
= 1,
889 .async_size
= sizeof(struct io_async_rw
),
891 [IORING_OP_WRITEV
] = {
894 .unbound_nonreg_file
= 1,
896 .needs_async_setup
= 1,
898 .async_size
= sizeof(struct io_async_rw
),
900 [IORING_OP_FSYNC
] = {
903 [IORING_OP_READ_FIXED
] = {
905 .unbound_nonreg_file
= 1,
908 .async_size
= sizeof(struct io_async_rw
),
910 [IORING_OP_WRITE_FIXED
] = {
913 .unbound_nonreg_file
= 1,
916 .async_size
= sizeof(struct io_async_rw
),
918 [IORING_OP_POLL_ADD
] = {
920 .unbound_nonreg_file
= 1,
922 [IORING_OP_POLL_REMOVE
] = {},
923 [IORING_OP_SYNC_FILE_RANGE
] = {
926 [IORING_OP_SENDMSG
] = {
928 .unbound_nonreg_file
= 1,
930 .needs_async_setup
= 1,
931 .async_size
= sizeof(struct io_async_msghdr
),
933 [IORING_OP_RECVMSG
] = {
935 .unbound_nonreg_file
= 1,
938 .needs_async_setup
= 1,
939 .async_size
= sizeof(struct io_async_msghdr
),
941 [IORING_OP_TIMEOUT
] = {
942 .async_size
= sizeof(struct io_timeout_data
),
944 [IORING_OP_TIMEOUT_REMOVE
] = {
945 /* used by timeout updates' prep() */
947 [IORING_OP_ACCEPT
] = {
949 .unbound_nonreg_file
= 1,
952 [IORING_OP_ASYNC_CANCEL
] = {},
953 [IORING_OP_LINK_TIMEOUT
] = {
954 .async_size
= sizeof(struct io_timeout_data
),
956 [IORING_OP_CONNECT
] = {
958 .unbound_nonreg_file
= 1,
960 .needs_async_setup
= 1,
961 .async_size
= sizeof(struct io_async_connect
),
963 [IORING_OP_FALLOCATE
] = {
966 [IORING_OP_OPENAT
] = {},
967 [IORING_OP_CLOSE
] = {},
968 [IORING_OP_FILES_UPDATE
] = {},
969 [IORING_OP_STATX
] = {},
972 .unbound_nonreg_file
= 1,
976 .async_size
= sizeof(struct io_async_rw
),
978 [IORING_OP_WRITE
] = {
980 .unbound_nonreg_file
= 1,
983 .async_size
= sizeof(struct io_async_rw
),
985 [IORING_OP_FADVISE
] = {
988 [IORING_OP_MADVISE
] = {},
991 .unbound_nonreg_file
= 1,
996 .unbound_nonreg_file
= 1,
1000 [IORING_OP_OPENAT2
] = {
1002 [IORING_OP_EPOLL_CTL
] = {
1003 .unbound_nonreg_file
= 1,
1005 [IORING_OP_SPLICE
] = {
1008 .unbound_nonreg_file
= 1,
1010 [IORING_OP_PROVIDE_BUFFERS
] = {},
1011 [IORING_OP_REMOVE_BUFFERS
] = {},
1015 .unbound_nonreg_file
= 1,
1017 [IORING_OP_SHUTDOWN
] = {
1020 [IORING_OP_RENAMEAT
] = {},
1021 [IORING_OP_UNLINKAT
] = {},
1024 static bool io_disarm_next(struct io_kiocb
*req
);
1025 static void io_uring_del_task_file(unsigned long index
);
1026 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
1027 struct task_struct
*task
,
1028 struct files_struct
*files
);
1029 static void io_uring_cancel_sqpoll(struct io_ring_ctx
*ctx
);
1030 static void io_rsrc_node_destroy(struct io_rsrc_node
*ref_node
);
1031 static struct io_rsrc_node
*io_rsrc_node_alloc(struct io_ring_ctx
*ctx
);
1032 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
);
1034 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
1035 static void io_put_req(struct io_kiocb
*req
);
1036 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
1037 static void io_dismantle_req(struct io_kiocb
*req
);
1038 static void io_put_task(struct task_struct
*task
, int nr
);
1039 static void io_queue_next(struct io_kiocb
*req
);
1040 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
1041 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1042 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
1043 struct io_uring_rsrc_update
*ip
,
1045 static void io_clean_op(struct io_kiocb
*req
);
1046 static struct file
*io_file_get(struct io_submit_state
*state
,
1047 struct io_kiocb
*req
, int fd
, bool fixed
);
1048 static void __io_queue_sqe(struct io_kiocb
*req
);
1049 static void io_rsrc_put_work(struct work_struct
*work
);
1051 static void io_req_task_queue(struct io_kiocb
*req
);
1052 static void io_submit_flush_completions(struct io_comp_state
*cs
,
1053 struct io_ring_ctx
*ctx
);
1054 static bool io_poll_remove_waitqs(struct io_kiocb
*req
);
1055 static int io_req_prep_async(struct io_kiocb
*req
);
1057 static struct kmem_cache
*req_cachep
;
1059 static const struct file_operations io_uring_fops
;
1061 struct sock
*io_uring_get_socket(struct file
*file
)
1063 #if defined(CONFIG_UNIX)
1064 if (file
->f_op
== &io_uring_fops
) {
1065 struct io_ring_ctx
*ctx
= file
->private_data
;
1067 return ctx
->ring_sock
->sk
;
1072 EXPORT_SYMBOL(io_uring_get_socket
);
1074 #define io_for_each_link(pos, head) \
1075 for (pos = (head); pos; pos = pos->link)
1077 static inline void io_req_set_rsrc_node(struct io_kiocb
*req
)
1079 struct io_ring_ctx
*ctx
= req
->ctx
;
1081 if (!req
->fixed_rsrc_refs
) {
1082 req
->fixed_rsrc_refs
= &ctx
->file_data
->node
->refs
;
1083 percpu_ref_get(req
->fixed_rsrc_refs
);
1087 static bool io_match_task(struct io_kiocb
*head
,
1088 struct task_struct
*task
,
1089 struct files_struct
*files
)
1091 struct io_kiocb
*req
;
1093 if (task
&& head
->task
!= task
)
1098 io_for_each_link(req
, head
) {
1099 if (req
->flags
& REQ_F_INFLIGHT
)
1105 static inline void req_set_fail_links(struct io_kiocb
*req
)
1107 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1108 req
->flags
|= REQ_F_FAIL_LINK
;
1111 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1113 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1115 complete(&ctx
->ref_comp
);
1118 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1120 return !req
->timeout
.off
;
1123 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1125 struct io_ring_ctx
*ctx
;
1128 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1133 * Use 5 bits less than the max cq entries, that should give us around
1134 * 32 entries per hash list if totally full and uniformly spread.
1136 hash_bits
= ilog2(p
->cq_entries
);
1140 ctx
->cancel_hash_bits
= hash_bits
;
1141 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1143 if (!ctx
->cancel_hash
)
1145 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1147 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1148 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1151 ctx
->flags
= p
->flags
;
1152 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1153 INIT_LIST_HEAD(&ctx
->sqd_list
);
1154 init_waitqueue_head(&ctx
->cq_wait
);
1155 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1156 init_completion(&ctx
->ref_comp
);
1157 xa_init_flags(&ctx
->io_buffers
, XA_FLAGS_ALLOC1
);
1158 xa_init_flags(&ctx
->personalities
, XA_FLAGS_ALLOC1
);
1159 mutex_init(&ctx
->uring_lock
);
1160 init_waitqueue_head(&ctx
->wait
);
1161 spin_lock_init(&ctx
->completion_lock
);
1162 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1163 INIT_LIST_HEAD(&ctx
->defer_list
);
1164 INIT_LIST_HEAD(&ctx
->timeout_list
);
1165 spin_lock_init(&ctx
->inflight_lock
);
1166 INIT_LIST_HEAD(&ctx
->inflight_list
);
1167 spin_lock_init(&ctx
->rsrc_ref_lock
);
1168 INIT_LIST_HEAD(&ctx
->rsrc_ref_list
);
1169 INIT_DELAYED_WORK(&ctx
->rsrc_put_work
, io_rsrc_put_work
);
1170 init_llist_head(&ctx
->rsrc_put_llist
);
1171 INIT_LIST_HEAD(&ctx
->tctx_list
);
1172 INIT_LIST_HEAD(&ctx
->submit_state
.comp
.free_list
);
1173 INIT_LIST_HEAD(&ctx
->submit_state
.comp
.locked_free_list
);
1176 kfree(ctx
->cancel_hash
);
1181 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1183 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1184 struct io_ring_ctx
*ctx
= req
->ctx
;
1186 return seq
!= ctx
->cached_cq_tail
1187 + READ_ONCE(ctx
->cached_cq_overflow
);
1193 static void io_req_track_inflight(struct io_kiocb
*req
)
1195 struct io_ring_ctx
*ctx
= req
->ctx
;
1197 if (!(req
->flags
& REQ_F_INFLIGHT
)) {
1198 req
->flags
|= REQ_F_INFLIGHT
;
1200 spin_lock_irq(&ctx
->inflight_lock
);
1201 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
1202 spin_unlock_irq(&ctx
->inflight_lock
);
1206 static void io_prep_async_work(struct io_kiocb
*req
)
1208 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1209 struct io_ring_ctx
*ctx
= req
->ctx
;
1211 if (!req
->work
.creds
)
1212 req
->work
.creds
= get_current_cred();
1214 req
->work
.list
.next
= NULL
;
1215 req
->work
.flags
= 0;
1216 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1217 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1219 if (req
->flags
& REQ_F_ISREG
) {
1220 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1221 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1222 } else if (!req
->file
|| !S_ISBLK(file_inode(req
->file
)->i_mode
)) {
1223 if (def
->unbound_nonreg_file
)
1224 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1227 switch (req
->opcode
) {
1228 case IORING_OP_SPLICE
:
1231 * Splice operation will be punted aync, and here need to
1232 * modify io_wq_work.flags, so initialize io_wq_work firstly.
1234 if (!S_ISREG(file_inode(req
->splice
.file_in
)->i_mode
))
1235 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1240 static void io_prep_async_link(struct io_kiocb
*req
)
1242 struct io_kiocb
*cur
;
1244 io_for_each_link(cur
, req
)
1245 io_prep_async_work(cur
);
1248 static void io_queue_async_work(struct io_kiocb
*req
)
1250 struct io_ring_ctx
*ctx
= req
->ctx
;
1251 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1252 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1255 BUG_ON(!tctx
->io_wq
);
1257 /* init ->work of the whole link before punting */
1258 io_prep_async_link(req
);
1259 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1260 &req
->work
, req
->flags
);
1261 io_wq_enqueue(tctx
->io_wq
, &req
->work
);
1263 io_queue_linked_timeout(link
);
1266 static void io_kill_timeout(struct io_kiocb
*req
, int status
)
1268 struct io_timeout_data
*io
= req
->async_data
;
1271 ret
= hrtimer_try_to_cancel(&io
->timer
);
1273 atomic_set(&req
->ctx
->cq_timeouts
,
1274 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1275 list_del_init(&req
->timeout
.list
);
1276 io_cqring_fill_event(req
, status
);
1277 io_put_req_deferred(req
, 1);
1281 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1284 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1285 struct io_defer_entry
, list
);
1287 if (req_need_defer(de
->req
, de
->seq
))
1289 list_del_init(&de
->list
);
1290 io_req_task_queue(de
->req
);
1292 } while (!list_empty(&ctx
->defer_list
));
1295 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1299 if (list_empty(&ctx
->timeout_list
))
1302 seq
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
1305 u32 events_needed
, events_got
;
1306 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1307 struct io_kiocb
, timeout
.list
);
1309 if (io_is_timeout_noseq(req
))
1313 * Since seq can easily wrap around over time, subtract
1314 * the last seq at which timeouts were flushed before comparing.
1315 * Assuming not more than 2^31-1 events have happened since,
1316 * these subtractions won't have wrapped, so we can check if
1317 * target is in [last_seq, current_seq] by comparing the two.
1319 events_needed
= req
->timeout
.target_seq
- ctx
->cq_last_tm_flush
;
1320 events_got
= seq
- ctx
->cq_last_tm_flush
;
1321 if (events_got
< events_needed
)
1324 list_del_init(&req
->timeout
.list
);
1325 io_kill_timeout(req
, 0);
1326 } while (!list_empty(&ctx
->timeout_list
));
1328 ctx
->cq_last_tm_flush
= seq
;
1331 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1333 io_flush_timeouts(ctx
);
1335 /* order cqe stores with ring update */
1336 smp_store_release(&ctx
->rings
->cq
.tail
, ctx
->cached_cq_tail
);
1338 if (unlikely(!list_empty(&ctx
->defer_list
)))
1339 __io_queue_deferred(ctx
);
1342 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1344 struct io_rings
*r
= ctx
->rings
;
1346 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1349 static inline unsigned int __io_cqring_events(struct io_ring_ctx
*ctx
)
1351 return ctx
->cached_cq_tail
- READ_ONCE(ctx
->rings
->cq
.head
);
1354 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1356 struct io_rings
*rings
= ctx
->rings
;
1360 * writes to the cq entry need to come after reading head; the
1361 * control dependency is enough as we're using WRITE_ONCE to
1364 if (__io_cqring_events(ctx
) == rings
->cq_ring_entries
)
1367 tail
= ctx
->cached_cq_tail
++;
1368 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1371 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1375 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1377 if (!ctx
->eventfd_async
)
1379 return io_wq_current_is_worker();
1382 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1384 /* see waitqueue_active() comment */
1387 if (waitqueue_active(&ctx
->wait
))
1388 wake_up(&ctx
->wait
);
1389 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1390 wake_up(&ctx
->sq_data
->wait
);
1391 if (io_should_trigger_evfd(ctx
))
1392 eventfd_signal(ctx
->cq_ev_fd
, 1);
1393 if (waitqueue_active(&ctx
->cq_wait
)) {
1394 wake_up_interruptible(&ctx
->cq_wait
);
1395 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1399 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx
*ctx
)
1401 /* see waitqueue_active() comment */
1404 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1405 if (waitqueue_active(&ctx
->wait
))
1406 wake_up(&ctx
->wait
);
1408 if (io_should_trigger_evfd(ctx
))
1409 eventfd_signal(ctx
->cq_ev_fd
, 1);
1410 if (waitqueue_active(&ctx
->cq_wait
)) {
1411 wake_up_interruptible(&ctx
->cq_wait
);
1412 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1416 /* Returns true if there are no backlogged entries after the flush */
1417 static bool __io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1419 struct io_rings
*rings
= ctx
->rings
;
1420 unsigned long flags
;
1421 bool all_flushed
, posted
;
1423 if (!force
&& __io_cqring_events(ctx
) == rings
->cq_ring_entries
)
1427 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1428 while (!list_empty(&ctx
->cq_overflow_list
)) {
1429 struct io_uring_cqe
*cqe
= io_get_cqring(ctx
);
1430 struct io_overflow_cqe
*ocqe
;
1434 ocqe
= list_first_entry(&ctx
->cq_overflow_list
,
1435 struct io_overflow_cqe
, list
);
1437 memcpy(cqe
, &ocqe
->cqe
, sizeof(*cqe
));
1439 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1440 ++ctx
->cached_cq_overflow
);
1442 list_del(&ocqe
->list
);
1446 all_flushed
= list_empty(&ctx
->cq_overflow_list
);
1448 clear_bit(0, &ctx
->sq_check_overflow
);
1449 clear_bit(0, &ctx
->cq_check_overflow
);
1450 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1454 io_commit_cqring(ctx
);
1455 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1457 io_cqring_ev_posted(ctx
);
1461 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1465 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1466 /* iopoll syncs against uring_lock, not completion_lock */
1467 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1468 mutex_lock(&ctx
->uring_lock
);
1469 ret
= __io_cqring_overflow_flush(ctx
, force
);
1470 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1471 mutex_unlock(&ctx
->uring_lock
);
1478 * Shamelessly stolen from the mm implementation of page reference checking,
1479 * see commit f958d7b528b1 for details.
1481 #define req_ref_zero_or_close_to_overflow(req) \
1482 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1484 static inline bool req_ref_inc_not_zero(struct io_kiocb
*req
)
1486 return atomic_inc_not_zero(&req
->refs
);
1489 static inline bool req_ref_sub_and_test(struct io_kiocb
*req
, int refs
)
1491 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1492 return atomic_sub_and_test(refs
, &req
->refs
);
1495 static inline bool req_ref_put_and_test(struct io_kiocb
*req
)
1497 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1498 return atomic_dec_and_test(&req
->refs
);
1501 static inline void req_ref_put(struct io_kiocb
*req
)
1503 WARN_ON_ONCE(req_ref_put_and_test(req
));
1506 static inline void req_ref_get(struct io_kiocb
*req
)
1508 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1509 atomic_inc(&req
->refs
);
1512 static bool __io_cqring_fill_event(struct io_kiocb
*req
, long res
,
1513 unsigned int cflags
)
1515 struct io_ring_ctx
*ctx
= req
->ctx
;
1516 struct io_uring_cqe
*cqe
;
1518 trace_io_uring_complete(ctx
, req
->user_data
, res
, cflags
);
1521 * If we can't get a cq entry, userspace overflowed the
1522 * submission (by quite a lot). Increment the overflow count in
1525 cqe
= io_get_cqring(ctx
);
1527 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1528 WRITE_ONCE(cqe
->res
, res
);
1529 WRITE_ONCE(cqe
->flags
, cflags
);
1532 if (!ctx
->cq_overflow_flushed
&&
1533 !atomic_read(&req
->task
->io_uring
->in_idle
)) {
1534 struct io_overflow_cqe
*ocqe
;
1536 ocqe
= kmalloc(sizeof(*ocqe
), GFP_ATOMIC
| __GFP_ACCOUNT
);
1539 if (list_empty(&ctx
->cq_overflow_list
)) {
1540 set_bit(0, &ctx
->sq_check_overflow
);
1541 set_bit(0, &ctx
->cq_check_overflow
);
1542 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1544 ocqe
->cqe
.user_data
= req
->user_data
;
1545 ocqe
->cqe
.res
= res
;
1546 ocqe
->cqe
.flags
= cflags
;
1547 list_add_tail(&ocqe
->list
, &ctx
->cq_overflow_list
);
1552 * If we're in ring overflow flush mode, or in task cancel mode,
1553 * or cannot allocate an overflow entry, then we need to drop it
1556 WRITE_ONCE(ctx
->rings
->cq_overflow
, ++ctx
->cached_cq_overflow
);
1560 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1562 __io_cqring_fill_event(req
, res
, 0);
1565 static void io_req_complete_post(struct io_kiocb
*req
, long res
,
1566 unsigned int cflags
)
1568 struct io_ring_ctx
*ctx
= req
->ctx
;
1569 unsigned long flags
;
1571 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1572 __io_cqring_fill_event(req
, res
, cflags
);
1574 * If we're the last reference to this request, add to our locked
1577 if (req_ref_put_and_test(req
)) {
1578 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
1580 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
1581 if (req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_FAIL_LINK
))
1582 io_disarm_next(req
);
1584 io_req_task_queue(req
->link
);
1588 io_dismantle_req(req
);
1589 io_put_task(req
->task
, 1);
1590 list_add(&req
->compl.list
, &cs
->locked_free_list
);
1591 cs
->locked_free_nr
++;
1593 if (!percpu_ref_tryget(&ctx
->refs
))
1596 io_commit_cqring(ctx
);
1597 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1600 io_cqring_ev_posted(ctx
);
1601 percpu_ref_put(&ctx
->refs
);
1605 static void io_req_complete_state(struct io_kiocb
*req
, long res
,
1606 unsigned int cflags
)
1608 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
))
1611 req
->compl.cflags
= cflags
;
1612 req
->flags
|= REQ_F_COMPLETE_INLINE
;
1615 static inline void __io_req_complete(struct io_kiocb
*req
, unsigned issue_flags
,
1616 long res
, unsigned cflags
)
1618 if (issue_flags
& IO_URING_F_COMPLETE_DEFER
)
1619 io_req_complete_state(req
, res
, cflags
);
1621 io_req_complete_post(req
, res
, cflags
);
1624 static inline void io_req_complete(struct io_kiocb
*req
, long res
)
1626 __io_req_complete(req
, 0, res
, 0);
1629 static void io_req_complete_failed(struct io_kiocb
*req
, long res
)
1631 req_set_fail_links(req
);
1633 io_req_complete_post(req
, res
, 0);
1636 static void io_flush_cached_locked_reqs(struct io_ring_ctx
*ctx
,
1637 struct io_comp_state
*cs
)
1639 spin_lock_irq(&ctx
->completion_lock
);
1640 list_splice_init(&cs
->locked_free_list
, &cs
->free_list
);
1641 cs
->locked_free_nr
= 0;
1642 spin_unlock_irq(&ctx
->completion_lock
);
1645 /* Returns true IFF there are requests in the cache */
1646 static bool io_flush_cached_reqs(struct io_ring_ctx
*ctx
)
1648 struct io_submit_state
*state
= &ctx
->submit_state
;
1649 struct io_comp_state
*cs
= &state
->comp
;
1653 * If we have more than a batch's worth of requests in our IRQ side
1654 * locked cache, grab the lock and move them over to our submission
1657 if (READ_ONCE(cs
->locked_free_nr
) > IO_COMPL_BATCH
)
1658 io_flush_cached_locked_reqs(ctx
, cs
);
1660 nr
= state
->free_reqs
;
1661 while (!list_empty(&cs
->free_list
)) {
1662 struct io_kiocb
*req
= list_first_entry(&cs
->free_list
,
1663 struct io_kiocb
, compl.list
);
1665 list_del(&req
->compl.list
);
1666 state
->reqs
[nr
++] = req
;
1667 if (nr
== ARRAY_SIZE(state
->reqs
))
1671 state
->free_reqs
= nr
;
1675 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
)
1677 struct io_submit_state
*state
= &ctx
->submit_state
;
1679 BUILD_BUG_ON(IO_REQ_ALLOC_BATCH
> ARRAY_SIZE(state
->reqs
));
1681 if (!state
->free_reqs
) {
1682 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1685 if (io_flush_cached_reqs(ctx
))
1688 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, IO_REQ_ALLOC_BATCH
,
1692 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1693 * retry single alloc to be on the safe side.
1695 if (unlikely(ret
<= 0)) {
1696 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1697 if (!state
->reqs
[0])
1701 state
->free_reqs
= ret
;
1705 return state
->reqs
[state
->free_reqs
];
1708 static inline void io_put_file(struct file
*file
)
1714 static void io_dismantle_req(struct io_kiocb
*req
)
1716 unsigned int flags
= req
->flags
;
1718 if (!(flags
& REQ_F_FIXED_FILE
))
1719 io_put_file(req
->file
);
1720 if (flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
|
1724 if (req
->flags
& REQ_F_INFLIGHT
) {
1725 struct io_ring_ctx
*ctx
= req
->ctx
;
1726 unsigned long flags
;
1728 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1729 list_del(&req
->inflight_entry
);
1730 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1731 req
->flags
&= ~REQ_F_INFLIGHT
;
1734 if (req
->fixed_rsrc_refs
)
1735 percpu_ref_put(req
->fixed_rsrc_refs
);
1736 if (req
->async_data
)
1737 kfree(req
->async_data
);
1738 if (req
->work
.creds
) {
1739 put_cred(req
->work
.creds
);
1740 req
->work
.creds
= NULL
;
1744 /* must to be called somewhat shortly after putting a request */
1745 static inline void io_put_task(struct task_struct
*task
, int nr
)
1747 struct io_uring_task
*tctx
= task
->io_uring
;
1749 percpu_counter_sub(&tctx
->inflight
, nr
);
1750 if (unlikely(atomic_read(&tctx
->in_idle
)))
1751 wake_up(&tctx
->wait
);
1752 put_task_struct_many(task
, nr
);
1755 static void __io_free_req(struct io_kiocb
*req
)
1757 struct io_ring_ctx
*ctx
= req
->ctx
;
1759 io_dismantle_req(req
);
1760 io_put_task(req
->task
, 1);
1762 kmem_cache_free(req_cachep
, req
);
1763 percpu_ref_put(&ctx
->refs
);
1766 static inline void io_remove_next_linked(struct io_kiocb
*req
)
1768 struct io_kiocb
*nxt
= req
->link
;
1770 req
->link
= nxt
->link
;
1774 static bool io_kill_linked_timeout(struct io_kiocb
*req
)
1775 __must_hold(&req
->ctx
->completion_lock
)
1777 struct io_kiocb
*link
= req
->link
;
1780 * Can happen if a linked timeout fired and link had been like
1781 * req -> link t-out -> link t-out [-> ...]
1783 if (link
&& (link
->flags
& REQ_F_LTIMEOUT_ACTIVE
)) {
1784 struct io_timeout_data
*io
= link
->async_data
;
1787 io_remove_next_linked(req
);
1788 link
->timeout
.head
= NULL
;
1789 ret
= hrtimer_try_to_cancel(&io
->timer
);
1791 io_cqring_fill_event(link
, -ECANCELED
);
1792 io_put_req_deferred(link
, 1);
1799 static void io_fail_links(struct io_kiocb
*req
)
1800 __must_hold(&req
->ctx
->completion_lock
)
1802 struct io_kiocb
*nxt
, *link
= req
->link
;
1809 trace_io_uring_fail_link(req
, link
);
1810 io_cqring_fill_event(link
, -ECANCELED
);
1811 io_put_req_deferred(link
, 2);
1816 static bool io_disarm_next(struct io_kiocb
*req
)
1817 __must_hold(&req
->ctx
->completion_lock
)
1819 bool posted
= false;
1821 if (likely(req
->flags
& REQ_F_LINK_TIMEOUT
))
1822 posted
= io_kill_linked_timeout(req
);
1823 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
1824 posted
|= (req
->link
!= NULL
);
1830 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
1832 struct io_kiocb
*nxt
;
1835 * If LINK is set, we have dependent requests in this chain. If we
1836 * didn't fail this request, queue the first one up, moving any other
1837 * dependencies to the next request. In case of failure, fail the rest
1840 if (req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_FAIL_LINK
)) {
1841 struct io_ring_ctx
*ctx
= req
->ctx
;
1842 unsigned long flags
;
1845 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1846 posted
= io_disarm_next(req
);
1848 io_commit_cqring(req
->ctx
);
1849 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1851 io_cqring_ev_posted(ctx
);
1858 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
1860 if (likely(!(req
->flags
& (REQ_F_LINK
|REQ_F_HARDLINK
))))
1862 return __io_req_find_next(req
);
1865 static void ctx_flush_and_put(struct io_ring_ctx
*ctx
)
1869 if (ctx
->submit_state
.comp
.nr
) {
1870 mutex_lock(&ctx
->uring_lock
);
1871 io_submit_flush_completions(&ctx
->submit_state
.comp
, ctx
);
1872 mutex_unlock(&ctx
->uring_lock
);
1874 percpu_ref_put(&ctx
->refs
);
1877 static bool __tctx_task_work(struct io_uring_task
*tctx
)
1879 struct io_ring_ctx
*ctx
= NULL
;
1880 struct io_wq_work_list list
;
1881 struct io_wq_work_node
*node
;
1883 if (wq_list_empty(&tctx
->task_list
))
1886 spin_lock_irq(&tctx
->task_lock
);
1887 list
= tctx
->task_list
;
1888 INIT_WQ_LIST(&tctx
->task_list
);
1889 spin_unlock_irq(&tctx
->task_lock
);
1893 struct io_wq_work_node
*next
= node
->next
;
1894 struct io_kiocb
*req
;
1896 req
= container_of(node
, struct io_kiocb
, io_task_work
.node
);
1897 if (req
->ctx
!= ctx
) {
1898 ctx_flush_and_put(ctx
);
1900 percpu_ref_get(&ctx
->refs
);
1903 req
->task_work
.func(&req
->task_work
);
1907 ctx_flush_and_put(ctx
);
1908 return list
.first
!= NULL
;
1911 static void tctx_task_work(struct callback_head
*cb
)
1913 struct io_uring_task
*tctx
= container_of(cb
, struct io_uring_task
, task_work
);
1915 clear_bit(0, &tctx
->task_state
);
1917 while (__tctx_task_work(tctx
))
1921 static int io_req_task_work_add(struct io_kiocb
*req
)
1923 struct task_struct
*tsk
= req
->task
;
1924 struct io_uring_task
*tctx
= tsk
->io_uring
;
1925 enum task_work_notify_mode notify
;
1926 struct io_wq_work_node
*node
, *prev
;
1927 unsigned long flags
;
1930 if (unlikely(tsk
->flags
& PF_EXITING
))
1933 WARN_ON_ONCE(!tctx
);
1935 spin_lock_irqsave(&tctx
->task_lock
, flags
);
1936 wq_list_add_tail(&req
->io_task_work
.node
, &tctx
->task_list
);
1937 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
1939 /* task_work already pending, we're done */
1940 if (test_bit(0, &tctx
->task_state
) ||
1941 test_and_set_bit(0, &tctx
->task_state
))
1945 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
1946 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
1947 * processing task_work. There's no reliable way to tell if TWA_RESUME
1950 notify
= (req
->ctx
->flags
& IORING_SETUP_SQPOLL
) ? TWA_NONE
: TWA_SIGNAL
;
1952 if (!task_work_add(tsk
, &tctx
->task_work
, notify
)) {
1953 wake_up_process(tsk
);
1958 * Slow path - we failed, find and delete work. if the work is not
1959 * in the list, it got run and we're fine.
1961 spin_lock_irqsave(&tctx
->task_lock
, flags
);
1962 wq_list_for_each(node
, prev
, &tctx
->task_list
) {
1963 if (&req
->io_task_work
.node
== node
) {
1964 wq_list_del(&tctx
->task_list
, node
, prev
);
1969 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
1970 clear_bit(0, &tctx
->task_state
);
1974 static bool io_run_task_work_head(struct callback_head
**work_head
)
1976 struct callback_head
*work
, *next
;
1977 bool executed
= false;
1980 work
= xchg(work_head
, NULL
);
1996 static void io_task_work_add_head(struct callback_head
**work_head
,
1997 struct callback_head
*task_work
)
1999 struct callback_head
*head
;
2002 head
= READ_ONCE(*work_head
);
2003 task_work
->next
= head
;
2004 } while (cmpxchg(work_head
, head
, task_work
) != head
);
2007 static void io_req_task_work_add_fallback(struct io_kiocb
*req
,
2008 task_work_func_t cb
)
2010 init_task_work(&req
->task_work
, cb
);
2011 io_task_work_add_head(&req
->ctx
->exit_task_work
, &req
->task_work
);
2014 static void io_req_task_cancel(struct callback_head
*cb
)
2016 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2017 struct io_ring_ctx
*ctx
= req
->ctx
;
2019 /* ctx is guaranteed to stay alive while we hold uring_lock */
2020 mutex_lock(&ctx
->uring_lock
);
2021 io_req_complete_failed(req
, req
->result
);
2022 mutex_unlock(&ctx
->uring_lock
);
2025 static void __io_req_task_submit(struct io_kiocb
*req
)
2027 struct io_ring_ctx
*ctx
= req
->ctx
;
2029 /* ctx stays valid until unlock, even if we drop all ours ctx->refs */
2030 mutex_lock(&ctx
->uring_lock
);
2031 if (!(current
->flags
& PF_EXITING
) && !current
->in_execve
)
2032 __io_queue_sqe(req
);
2034 io_req_complete_failed(req
, -EFAULT
);
2035 mutex_unlock(&ctx
->uring_lock
);
2038 static void io_req_task_submit(struct callback_head
*cb
)
2040 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2042 __io_req_task_submit(req
);
2045 static void io_req_task_queue_fail(struct io_kiocb
*req
, int ret
)
2048 req
->task_work
.func
= io_req_task_cancel
;
2050 if (unlikely(io_req_task_work_add(req
)))
2051 io_req_task_work_add_fallback(req
, io_req_task_cancel
);
2054 static void io_req_task_queue(struct io_kiocb
*req
)
2056 req
->task_work
.func
= io_req_task_submit
;
2058 if (unlikely(io_req_task_work_add(req
)))
2059 io_req_task_queue_fail(req
, -ECANCELED
);
2062 static inline void io_queue_next(struct io_kiocb
*req
)
2064 struct io_kiocb
*nxt
= io_req_find_next(req
);
2067 io_req_task_queue(nxt
);
2070 static void io_free_req(struct io_kiocb
*req
)
2077 struct task_struct
*task
;
2082 static inline void io_init_req_batch(struct req_batch
*rb
)
2089 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2090 struct req_batch
*rb
)
2093 io_put_task(rb
->task
, rb
->task_refs
);
2095 percpu_ref_put_many(&ctx
->refs
, rb
->ctx_refs
);
2098 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
,
2099 struct io_submit_state
*state
)
2102 io_dismantle_req(req
);
2104 if (req
->task
!= rb
->task
) {
2106 io_put_task(rb
->task
, rb
->task_refs
);
2107 rb
->task
= req
->task
;
2113 if (state
->free_reqs
!= ARRAY_SIZE(state
->reqs
))
2114 state
->reqs
[state
->free_reqs
++] = req
;
2116 list_add(&req
->compl.list
, &state
->comp
.free_list
);
2119 static void io_submit_flush_completions(struct io_comp_state
*cs
,
2120 struct io_ring_ctx
*ctx
)
2123 struct io_kiocb
*req
;
2124 struct req_batch rb
;
2126 io_init_req_batch(&rb
);
2127 spin_lock_irq(&ctx
->completion_lock
);
2128 for (i
= 0; i
< nr
; i
++) {
2130 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
2132 io_commit_cqring(ctx
);
2133 spin_unlock_irq(&ctx
->completion_lock
);
2135 io_cqring_ev_posted(ctx
);
2136 for (i
= 0; i
< nr
; i
++) {
2139 /* submission and completion refs */
2140 if (req_ref_sub_and_test(req
, 2))
2141 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2144 io_req_free_batch_finish(ctx
, &rb
);
2149 * Drop reference to request, return next in chain (if there is one) if this
2150 * was the last reference to this request.
2152 static inline struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2154 struct io_kiocb
*nxt
= NULL
;
2156 if (req_ref_put_and_test(req
)) {
2157 nxt
= io_req_find_next(req
);
2163 static inline void io_put_req(struct io_kiocb
*req
)
2165 if (req_ref_put_and_test(req
))
2169 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2171 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2176 static void io_free_req_deferred(struct io_kiocb
*req
)
2178 req
->task_work
.func
= io_put_req_deferred_cb
;
2179 if (unlikely(io_req_task_work_add(req
)))
2180 io_req_task_work_add_fallback(req
, io_put_req_deferred_cb
);
2183 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2185 if (req_ref_sub_and_test(req
, refs
))
2186 io_free_req_deferred(req
);
2189 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
)
2191 /* See comment at the top of this file */
2193 return __io_cqring_events(ctx
);
2196 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2198 struct io_rings
*rings
= ctx
->rings
;
2200 /* make sure SQ entry isn't read before tail */
2201 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2204 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2206 unsigned int cflags
;
2208 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2209 cflags
|= IORING_CQE_F_BUFFER
;
2210 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2215 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2217 struct io_buffer
*kbuf
;
2219 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2220 return io_put_kbuf(req
, kbuf
);
2223 static inline bool io_run_task_work(void)
2226 * Not safe to run on exiting task, and the task_work handling will
2227 * not add work to such a task.
2229 if (unlikely(current
->flags
& PF_EXITING
))
2231 if (current
->task_works
) {
2232 __set_current_state(TASK_RUNNING
);
2241 * Find and free completed poll iocbs
2243 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2244 struct list_head
*done
)
2246 struct req_batch rb
;
2247 struct io_kiocb
*req
;
2249 /* order with ->result store in io_complete_rw_iopoll() */
2252 io_init_req_batch(&rb
);
2253 while (!list_empty(done
)) {
2256 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2257 list_del(&req
->inflight_entry
);
2259 if (READ_ONCE(req
->result
) == -EAGAIN
&&
2260 !(req
->flags
& REQ_F_DONT_REISSUE
)) {
2261 req
->iopoll_completed
= 0;
2263 io_queue_async_work(req
);
2267 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2268 cflags
= io_put_rw_kbuf(req
);
2270 __io_cqring_fill_event(req
, req
->result
, cflags
);
2273 if (req_ref_put_and_test(req
))
2274 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2277 io_commit_cqring(ctx
);
2278 io_cqring_ev_posted_iopoll(ctx
);
2279 io_req_free_batch_finish(ctx
, &rb
);
2282 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2285 struct io_kiocb
*req
, *tmp
;
2291 * Only spin for completions if we don't have multiple devices hanging
2292 * off our complete list, and we're under the requested amount.
2294 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2297 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2298 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2301 * Move completed and retryable entries to our local lists.
2302 * If we find a request that requires polling, break out
2303 * and complete those lists first, if we have entries there.
2305 if (READ_ONCE(req
->iopoll_completed
)) {
2306 list_move_tail(&req
->inflight_entry
, &done
);
2309 if (!list_empty(&done
))
2312 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2316 /* iopoll may have completed current req */
2317 if (READ_ONCE(req
->iopoll_completed
))
2318 list_move_tail(&req
->inflight_entry
, &done
);
2325 if (!list_empty(&done
))
2326 io_iopoll_complete(ctx
, nr_events
, &done
);
2332 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2333 * non-spinning poll check - we'll still enter the driver poll loop, but only
2334 * as a non-spinning completion check.
2336 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2339 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2342 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2345 if (*nr_events
>= min
)
2353 * We can't just wait for polled events to come to us, we have to actively
2354 * find and complete them.
2356 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2358 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2361 mutex_lock(&ctx
->uring_lock
);
2362 while (!list_empty(&ctx
->iopoll_list
)) {
2363 unsigned int nr_events
= 0;
2365 io_do_iopoll(ctx
, &nr_events
, 0);
2367 /* let it sleep and repeat later if can't complete a request */
2371 * Ensure we allow local-to-the-cpu processing to take place,
2372 * in this case we need to ensure that we reap all events.
2373 * Also let task_work, etc. to progress by releasing the mutex
2375 if (need_resched()) {
2376 mutex_unlock(&ctx
->uring_lock
);
2378 mutex_lock(&ctx
->uring_lock
);
2381 mutex_unlock(&ctx
->uring_lock
);
2384 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2386 unsigned int nr_events
= 0;
2387 int iters
= 0, ret
= 0;
2390 * We disallow the app entering submit/complete with polling, but we
2391 * still need to lock the ring to prevent racing with polled issue
2392 * that got punted to a workqueue.
2394 mutex_lock(&ctx
->uring_lock
);
2397 * Don't enter poll loop if we already have events pending.
2398 * If we do, we can potentially be spinning for commands that
2399 * already triggered a CQE (eg in error).
2401 if (test_bit(0, &ctx
->cq_check_overflow
))
2402 __io_cqring_overflow_flush(ctx
, false);
2403 if (io_cqring_events(ctx
))
2407 * If a submit got punted to a workqueue, we can have the
2408 * application entering polling for a command before it gets
2409 * issued. That app will hold the uring_lock for the duration
2410 * of the poll right here, so we need to take a breather every
2411 * now and then to ensure that the issue has a chance to add
2412 * the poll to the issued list. Otherwise we can spin here
2413 * forever, while the workqueue is stuck trying to acquire the
2416 if (!(++iters
& 7)) {
2417 mutex_unlock(&ctx
->uring_lock
);
2419 mutex_lock(&ctx
->uring_lock
);
2422 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2426 } while (min
&& !nr_events
&& !need_resched());
2428 mutex_unlock(&ctx
->uring_lock
);
2432 static void kiocb_end_write(struct io_kiocb
*req
)
2435 * Tell lockdep we inherited freeze protection from submission
2438 if (req
->flags
& REQ_F_ISREG
) {
2439 struct super_block
*sb
= file_inode(req
->file
)->i_sb
;
2441 __sb_writers_acquired(sb
, SB_FREEZE_WRITE
);
2447 static bool io_resubmit_prep(struct io_kiocb
*req
)
2449 struct io_async_rw
*rw
= req
->async_data
;
2452 return !io_req_prep_async(req
);
2453 /* may have left rw->iter inconsistent on -EIOCBQUEUED */
2454 iov_iter_revert(&rw
->iter
, req
->result
- iov_iter_count(&rw
->iter
));
2458 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2460 umode_t mode
= file_inode(req
->file
)->i_mode
;
2461 struct io_ring_ctx
*ctx
= req
->ctx
;
2463 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2465 if ((req
->flags
& REQ_F_NOWAIT
) || (io_wq_current_is_worker() &&
2466 !(ctx
->flags
& IORING_SETUP_IOPOLL
)))
2469 * If ref is dying, we might be running poll reap from the exit work.
2470 * Don't attempt to reissue from that path, just let it fail with
2473 if (percpu_ref_is_dying(&ctx
->refs
))
2478 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2484 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2485 unsigned int issue_flags
)
2489 if (req
->rw
.kiocb
.ki_flags
& IOCB_WRITE
)
2490 kiocb_end_write(req
);
2491 if (res
!= req
->result
) {
2492 if ((res
== -EAGAIN
|| res
== -EOPNOTSUPP
) &&
2493 io_rw_should_reissue(req
)) {
2494 req
->flags
|= REQ_F_REISSUE
;
2497 req_set_fail_links(req
);
2499 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2500 cflags
= io_put_rw_kbuf(req
);
2501 __io_req_complete(req
, issue_flags
, res
, cflags
);
2504 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2506 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2508 __io_complete_rw(req
, res
, res2
, 0);
2511 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2513 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2515 if (kiocb
->ki_flags
& IOCB_WRITE
)
2516 kiocb_end_write(req
);
2517 if (unlikely(res
!= req
->result
)) {
2521 if (res
== -EAGAIN
&& io_rw_should_reissue(req
) &&
2522 io_resubmit_prep(req
))
2526 req_set_fail_links(req
);
2527 req
->flags
|= REQ_F_DONT_REISSUE
;
2531 WRITE_ONCE(req
->result
, res
);
2532 /* order with io_iopoll_complete() checking ->result */
2534 WRITE_ONCE(req
->iopoll_completed
, 1);
2538 * After the iocb has been issued, it's safe to be found on the poll list.
2539 * Adding the kiocb to the list AFTER submission ensures that we don't
2540 * find it from a io_iopoll_getevents() thread before the issuer is done
2541 * accessing the kiocb cookie.
2543 static void io_iopoll_req_issued(struct io_kiocb
*req
, bool in_async
)
2545 struct io_ring_ctx
*ctx
= req
->ctx
;
2548 * Track whether we have multiple files in our lists. This will impact
2549 * how we do polling eventually, not spinning if we're on potentially
2550 * different devices.
2552 if (list_empty(&ctx
->iopoll_list
)) {
2553 ctx
->poll_multi_file
= false;
2554 } else if (!ctx
->poll_multi_file
) {
2555 struct io_kiocb
*list_req
;
2557 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2559 if (list_req
->file
!= req
->file
)
2560 ctx
->poll_multi_file
= true;
2564 * For fast devices, IO may have already completed. If it has, add
2565 * it to the front so we find it first.
2567 if (READ_ONCE(req
->iopoll_completed
))
2568 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2570 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2573 * If IORING_SETUP_SQPOLL is enabled, sqes are either handled in sq thread
2574 * task context or in io worker task context. If current task context is
2575 * sq thread, we don't need to check whether should wake up sq thread.
2577 if (in_async
&& (ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2578 wq_has_sleeper(&ctx
->sq_data
->wait
))
2579 wake_up(&ctx
->sq_data
->wait
);
2582 static inline void io_state_file_put(struct io_submit_state
*state
)
2584 if (state
->file_refs
) {
2585 fput_many(state
->file
, state
->file_refs
);
2586 state
->file_refs
= 0;
2591 * Get as many references to a file as we have IOs left in this submission,
2592 * assuming most submissions are for one file, or at least that each file
2593 * has more than one submission.
2595 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2600 if (state
->file_refs
) {
2601 if (state
->fd
== fd
) {
2605 io_state_file_put(state
);
2607 state
->file
= fget_many(fd
, state
->ios_left
);
2608 if (unlikely(!state
->file
))
2612 state
->file_refs
= state
->ios_left
- 1;
2616 static bool io_bdev_nowait(struct block_device
*bdev
)
2618 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2622 * If we tracked the file through the SCM inflight mechanism, we could support
2623 * any file. For now, just ensure that anything potentially problematic is done
2626 static bool __io_file_supports_async(struct file
*file
, int rw
)
2628 umode_t mode
= file_inode(file
)->i_mode
;
2630 if (S_ISBLK(mode
)) {
2631 if (IS_ENABLED(CONFIG_BLOCK
) &&
2632 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2636 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2638 if (S_ISREG(mode
)) {
2639 if (IS_ENABLED(CONFIG_BLOCK
) &&
2640 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2641 file
->f_op
!= &io_uring_fops
)
2646 /* any ->read/write should understand O_NONBLOCK */
2647 if (file
->f_flags
& O_NONBLOCK
)
2650 if (!(file
->f_mode
& FMODE_NOWAIT
))
2654 return file
->f_op
->read_iter
!= NULL
;
2656 return file
->f_op
->write_iter
!= NULL
;
2659 static bool io_file_supports_async(struct io_kiocb
*req
, int rw
)
2661 if (rw
== READ
&& (req
->flags
& REQ_F_ASYNC_READ
))
2663 else if (rw
== WRITE
&& (req
->flags
& REQ_F_ASYNC_WRITE
))
2666 return __io_file_supports_async(req
->file
, rw
);
2669 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2671 struct io_ring_ctx
*ctx
= req
->ctx
;
2672 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2673 struct file
*file
= req
->file
;
2677 if (!(req
->flags
& REQ_F_ISREG
) && S_ISREG(file_inode(file
)->i_mode
))
2678 req
->flags
|= REQ_F_ISREG
;
2680 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2681 if (kiocb
->ki_pos
== -1 && !(file
->f_mode
& FMODE_STREAM
)) {
2682 req
->flags
|= REQ_F_CUR_POS
;
2683 kiocb
->ki_pos
= file
->f_pos
;
2685 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2686 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2687 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2691 /* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
2692 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) || (file
->f_flags
& O_NONBLOCK
))
2693 req
->flags
|= REQ_F_NOWAIT
;
2695 ioprio
= READ_ONCE(sqe
->ioprio
);
2697 ret
= ioprio_check_cap(ioprio
);
2701 kiocb
->ki_ioprio
= ioprio
;
2703 kiocb
->ki_ioprio
= get_current_ioprio();
2705 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2706 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2707 !kiocb
->ki_filp
->f_op
->iopoll
)
2710 kiocb
->ki_flags
|= IOCB_HIPRI
;
2711 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2712 req
->iopoll_completed
= 0;
2714 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2716 kiocb
->ki_complete
= io_complete_rw
;
2719 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2720 req
->rw
.len
= READ_ONCE(sqe
->len
);
2721 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2725 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2731 case -ERESTARTNOINTR
:
2732 case -ERESTARTNOHAND
:
2733 case -ERESTART_RESTARTBLOCK
:
2735 * We can't just restart the syscall, since previously
2736 * submitted sqes may already be in progress. Just fail this
2742 kiocb
->ki_complete(kiocb
, ret
, 0);
2746 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2747 unsigned int issue_flags
)
2749 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2750 struct io_async_rw
*io
= req
->async_data
;
2751 bool check_reissue
= kiocb
->ki_complete
== io_complete_rw
;
2753 /* add previously done IO, if any */
2754 if (io
&& io
->bytes_done
> 0) {
2756 ret
= io
->bytes_done
;
2758 ret
+= io
->bytes_done
;
2761 if (req
->flags
& REQ_F_CUR_POS
)
2762 req
->file
->f_pos
= kiocb
->ki_pos
;
2763 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2764 __io_complete_rw(req
, ret
, 0, issue_flags
);
2766 io_rw_done(kiocb
, ret
);
2768 if (check_reissue
&& req
->flags
& REQ_F_REISSUE
) {
2769 req
->flags
&= ~REQ_F_REISSUE
;
2770 if (!io_resubmit_prep(req
)) {
2772 io_queue_async_work(req
);
2776 req_set_fail_links(req
);
2777 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2778 cflags
= io_put_rw_kbuf(req
);
2779 __io_req_complete(req
, issue_flags
, ret
, cflags
);
2784 static int io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
)
2786 struct io_ring_ctx
*ctx
= req
->ctx
;
2787 size_t len
= req
->rw
.len
;
2788 struct io_mapped_ubuf
*imu
;
2789 u16 index
, buf_index
= req
->buf_index
;
2793 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2795 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2796 imu
= &ctx
->user_bufs
[index
];
2797 buf_addr
= req
->rw
.addr
;
2800 if (buf_addr
+ len
< buf_addr
)
2802 /* not inside the mapped region */
2803 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2807 * May not be a start of buffer, set size appropriately
2808 * and advance us to the beginning.
2810 offset
= buf_addr
- imu
->ubuf
;
2811 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2815 * Don't use iov_iter_advance() here, as it's really slow for
2816 * using the latter parts of a big fixed buffer - it iterates
2817 * over each segment manually. We can cheat a bit here, because
2820 * 1) it's a BVEC iter, we set it up
2821 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2822 * first and last bvec
2824 * So just find our index, and adjust the iterator afterwards.
2825 * If the offset is within the first bvec (or the whole first
2826 * bvec, just use iov_iter_advance(). This makes it easier
2827 * since we can just skip the first segment, which may not
2828 * be PAGE_SIZE aligned.
2830 const struct bio_vec
*bvec
= imu
->bvec
;
2832 if (offset
<= bvec
->bv_len
) {
2833 iov_iter_advance(iter
, offset
);
2835 unsigned long seg_skip
;
2837 /* skip first vec */
2838 offset
-= bvec
->bv_len
;
2839 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2841 iter
->bvec
= bvec
+ seg_skip
;
2842 iter
->nr_segs
-= seg_skip
;
2843 iter
->count
-= bvec
->bv_len
+ offset
;
2844 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2851 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2854 mutex_unlock(&ctx
->uring_lock
);
2857 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2860 * "Normal" inline submissions always hold the uring_lock, since we
2861 * grab it from the system call. Same is true for the SQPOLL offload.
2862 * The only exception is when we've detached the request and issue it
2863 * from an async worker thread, grab the lock for that case.
2866 mutex_lock(&ctx
->uring_lock
);
2869 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2870 int bgid
, struct io_buffer
*kbuf
,
2873 struct io_buffer
*head
;
2875 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2878 io_ring_submit_lock(req
->ctx
, needs_lock
);
2880 lockdep_assert_held(&req
->ctx
->uring_lock
);
2882 head
= xa_load(&req
->ctx
->io_buffers
, bgid
);
2884 if (!list_empty(&head
->list
)) {
2885 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2887 list_del(&kbuf
->list
);
2890 xa_erase(&req
->ctx
->io_buffers
, bgid
);
2892 if (*len
> kbuf
->len
)
2895 kbuf
= ERR_PTR(-ENOBUFS
);
2898 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2903 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2906 struct io_buffer
*kbuf
;
2909 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2910 bgid
= req
->buf_index
;
2911 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2914 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2915 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2916 return u64_to_user_ptr(kbuf
->addr
);
2919 #ifdef CONFIG_COMPAT
2920 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2923 struct compat_iovec __user
*uiov
;
2924 compat_ssize_t clen
;
2928 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2929 if (!access_ok(uiov
, sizeof(*uiov
)))
2931 if (__get_user(clen
, &uiov
->iov_len
))
2937 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2939 return PTR_ERR(buf
);
2940 iov
[0].iov_base
= buf
;
2941 iov
[0].iov_len
= (compat_size_t
) len
;
2946 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2949 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2953 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
2956 len
= iov
[0].iov_len
;
2959 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2961 return PTR_ERR(buf
);
2962 iov
[0].iov_base
= buf
;
2963 iov
[0].iov_len
= len
;
2967 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2970 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
2971 struct io_buffer
*kbuf
;
2973 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2974 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
2975 iov
[0].iov_len
= kbuf
->len
;
2978 if (req
->rw
.len
!= 1)
2981 #ifdef CONFIG_COMPAT
2982 if (req
->ctx
->compat
)
2983 return io_compat_import(req
, iov
, needs_lock
);
2986 return __io_iov_buffer_select(req
, iov
, needs_lock
);
2989 static int io_import_iovec(int rw
, struct io_kiocb
*req
, struct iovec
**iovec
,
2990 struct iov_iter
*iter
, bool needs_lock
)
2992 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
2993 size_t sqe_len
= req
->rw
.len
;
2994 u8 opcode
= req
->opcode
;
2997 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
2999 return io_import_fixed(req
, rw
, iter
);
3002 /* buffer index only valid with fixed read/write, or buffer select */
3003 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3006 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3007 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3008 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3010 return PTR_ERR(buf
);
3011 req
->rw
.len
= sqe_len
;
3014 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3019 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3020 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3022 iov_iter_init(iter
, rw
, *iovec
, 1, (*iovec
)->iov_len
);
3027 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3031 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3033 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3037 * For files that don't have ->read_iter() and ->write_iter(), handle them
3038 * by looping over ->read() or ->write() manually.
3040 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3042 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3043 struct file
*file
= req
->file
;
3047 * Don't support polled IO through this interface, and we can't
3048 * support non-blocking either. For the latter, this just causes
3049 * the kiocb to be handled from an async context.
3051 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3053 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3056 while (iov_iter_count(iter
)) {
3060 if (!iov_iter_is_bvec(iter
)) {
3061 iovec
= iov_iter_iovec(iter
);
3063 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3064 iovec
.iov_len
= req
->rw
.len
;
3068 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3069 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3071 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3072 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3081 if (nr
!= iovec
.iov_len
)
3085 iov_iter_advance(iter
, nr
);
3091 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3092 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3094 struct io_async_rw
*rw
= req
->async_data
;
3096 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3097 rw
->free_iovec
= iovec
;
3099 /* can only be fixed buffers, no need to do anything */
3100 if (iov_iter_is_bvec(iter
))
3103 unsigned iov_off
= 0;
3105 rw
->iter
.iov
= rw
->fast_iov
;
3106 if (iter
->iov
!= fast_iov
) {
3107 iov_off
= iter
->iov
- fast_iov
;
3108 rw
->iter
.iov
+= iov_off
;
3110 if (rw
->fast_iov
!= fast_iov
)
3111 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3112 sizeof(struct iovec
) * iter
->nr_segs
);
3114 req
->flags
|= REQ_F_NEED_CLEANUP
;
3118 static inline int io_alloc_async_data(struct io_kiocb
*req
)
3120 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3121 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3122 return req
->async_data
== NULL
;
3125 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3126 const struct iovec
*fast_iov
,
3127 struct iov_iter
*iter
, bool force
)
3129 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_setup
)
3131 if (!req
->async_data
) {
3132 if (io_alloc_async_data(req
)) {
3137 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3142 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3144 struct io_async_rw
*iorw
= req
->async_data
;
3145 struct iovec
*iov
= iorw
->fast_iov
;
3148 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3149 if (unlikely(ret
< 0))
3152 iorw
->bytes_done
= 0;
3153 iorw
->free_iovec
= iov
;
3155 req
->flags
|= REQ_F_NEED_CLEANUP
;
3159 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3161 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3163 return io_prep_rw(req
, sqe
);
3167 * This is our waitqueue callback handler, registered through lock_page_async()
3168 * when we initially tried to do the IO with the iocb armed our waitqueue.
3169 * This gets called when the page is unlocked, and we generally expect that to
3170 * happen when the page IO is completed and the page is now uptodate. This will
3171 * queue a task_work based retry of the operation, attempting to copy the data
3172 * again. If the latter fails because the page was NOT uptodate, then we will
3173 * do a thread based blocking retry of the operation. That's the unexpected
3176 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3177 int sync
, void *arg
)
3179 struct wait_page_queue
*wpq
;
3180 struct io_kiocb
*req
= wait
->private;
3181 struct wait_page_key
*key
= arg
;
3183 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3185 if (!wake_page_match(wpq
, key
))
3188 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3189 list_del_init(&wait
->entry
);
3191 /* submit ref gets dropped, acquire a new one */
3193 io_req_task_queue(req
);
3198 * This controls whether a given IO request should be armed for async page
3199 * based retry. If we return false here, the request is handed to the async
3200 * worker threads for retry. If we're doing buffered reads on a regular file,
3201 * we prepare a private wait_page_queue entry and retry the operation. This
3202 * will either succeed because the page is now uptodate and unlocked, or it
3203 * will register a callback when the page is unlocked at IO completion. Through
3204 * that callback, io_uring uses task_work to setup a retry of the operation.
3205 * That retry will attempt the buffered read again. The retry will generally
3206 * succeed, or in rare cases where it fails, we then fall back to using the
3207 * async worker threads for a blocking retry.
3209 static bool io_rw_should_retry(struct io_kiocb
*req
)
3211 struct io_async_rw
*rw
= req
->async_data
;
3212 struct wait_page_queue
*wait
= &rw
->wpq
;
3213 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3215 /* never retry for NOWAIT, we just complete with -EAGAIN */
3216 if (req
->flags
& REQ_F_NOWAIT
)
3219 /* Only for buffered IO */
3220 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3224 * just use poll if we can, and don't attempt if the fs doesn't
3225 * support callback based unlocks
3227 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3230 wait
->wait
.func
= io_async_buf_func
;
3231 wait
->wait
.private = req
;
3232 wait
->wait
.flags
= 0;
3233 INIT_LIST_HEAD(&wait
->wait
.entry
);
3234 kiocb
->ki_flags
|= IOCB_WAITQ
;
3235 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3236 kiocb
->ki_waitq
= wait
;
3240 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3242 if (req
->file
->f_op
->read_iter
)
3243 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3244 else if (req
->file
->f_op
->read
)
3245 return loop_rw_iter(READ
, req
, iter
);
3250 static int io_read(struct io_kiocb
*req
, unsigned int issue_flags
)
3252 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3253 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3254 struct iov_iter __iter
, *iter
= &__iter
;
3255 struct io_async_rw
*rw
= req
->async_data
;
3256 ssize_t io_size
, ret
, ret2
;
3257 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3263 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3267 io_size
= iov_iter_count(iter
);
3268 req
->result
= io_size
;
3270 /* Ensure we clear previously set non-block flag */
3271 if (!force_nonblock
)
3272 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3274 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3276 /* If the file doesn't support async, just async punt */
3277 if (force_nonblock
&& !io_file_supports_async(req
, READ
)) {
3278 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3279 return ret
?: -EAGAIN
;
3282 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3283 if (unlikely(ret
)) {
3288 ret
= io_iter_do_read(req
, iter
);
3290 if (ret
== -EAGAIN
|| (req
->flags
& REQ_F_REISSUE
)) {
3291 req
->flags
&= ~REQ_F_REISSUE
;
3292 /* IOPOLL retry should happen for io-wq threads */
3293 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3295 /* no retry on NONBLOCK nor RWF_NOWAIT */
3296 if (req
->flags
& REQ_F_NOWAIT
)
3298 /* some cases will consume bytes even on error returns */
3299 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3301 } else if (ret
== -EIOCBQUEUED
) {
3303 } else if (ret
<= 0 || ret
== io_size
|| !force_nonblock
||
3304 (req
->flags
& REQ_F_NOWAIT
) || !(req
->flags
& REQ_F_ISREG
)) {
3305 /* read all, failed, already did sync or don't want to retry */
3309 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3314 rw
= req
->async_data
;
3315 /* now use our persistent iterator, if we aren't already */
3320 rw
->bytes_done
+= ret
;
3321 /* if we can retry, do so with the callbacks armed */
3322 if (!io_rw_should_retry(req
)) {
3323 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3328 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3329 * we get -EIOCBQUEUED, then we'll get a notification when the
3330 * desired page gets unlocked. We can also get a partial read
3331 * here, and if we do, then just retry at the new offset.
3333 ret
= io_iter_do_read(req
, iter
);
3334 if (ret
== -EIOCBQUEUED
)
3336 /* we got some bytes, but not all. retry. */
3337 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3338 } while (ret
> 0 && ret
< io_size
);
3340 kiocb_done(kiocb
, ret
, issue_flags
);
3342 /* it's faster to check here then delegate to kfree */
3348 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3350 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3352 return io_prep_rw(req
, sqe
);
3355 static int io_write(struct io_kiocb
*req
, unsigned int issue_flags
)
3357 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3358 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3359 struct iov_iter __iter
, *iter
= &__iter
;
3360 struct io_async_rw
*rw
= req
->async_data
;
3361 ssize_t ret
, ret2
, io_size
;
3362 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3368 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3372 io_size
= iov_iter_count(iter
);
3373 req
->result
= io_size
;
3375 /* Ensure we clear previously set non-block flag */
3376 if (!force_nonblock
)
3377 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3379 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3381 /* If the file doesn't support async, just async punt */
3382 if (force_nonblock
&& !io_file_supports_async(req
, WRITE
))
3385 /* file path doesn't support NOWAIT for non-direct_IO */
3386 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3387 (req
->flags
& REQ_F_ISREG
))
3390 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3395 * Open-code file_start_write here to grab freeze protection,
3396 * which will be released by another thread in
3397 * io_complete_rw(). Fool lockdep by telling it the lock got
3398 * released so that it doesn't complain about the held lock when
3399 * we return to userspace.
3401 if (req
->flags
& REQ_F_ISREG
) {
3402 sb_start_write(file_inode(req
->file
)->i_sb
);
3403 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3406 kiocb
->ki_flags
|= IOCB_WRITE
;
3408 if (req
->file
->f_op
->write_iter
)
3409 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3410 else if (req
->file
->f_op
->write
)
3411 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3415 if (req
->flags
& REQ_F_REISSUE
) {
3416 req
->flags
&= ~REQ_F_REISSUE
;
3421 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3422 * retry them without IOCB_NOWAIT.
3424 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3426 /* no retry on NONBLOCK nor RWF_NOWAIT */
3427 if (ret2
== -EAGAIN
&& (req
->flags
& REQ_F_NOWAIT
))
3429 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3430 /* IOPOLL retry should happen for io-wq threads */
3431 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3434 kiocb_done(kiocb
, ret2
, issue_flags
);
3437 /* some cases will consume bytes even on error returns */
3438 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3439 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3440 return ret
?: -EAGAIN
;
3443 /* it's reportedly faster than delegating the null check to kfree() */
3449 static int io_renameat_prep(struct io_kiocb
*req
,
3450 const struct io_uring_sqe
*sqe
)
3452 struct io_rename
*ren
= &req
->rename
;
3453 const char __user
*oldf
, *newf
;
3455 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3458 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3459 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3460 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3461 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3462 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3464 ren
->oldpath
= getname(oldf
);
3465 if (IS_ERR(ren
->oldpath
))
3466 return PTR_ERR(ren
->oldpath
);
3468 ren
->newpath
= getname(newf
);
3469 if (IS_ERR(ren
->newpath
)) {
3470 putname(ren
->oldpath
);
3471 return PTR_ERR(ren
->newpath
);
3474 req
->flags
|= REQ_F_NEED_CLEANUP
;
3478 static int io_renameat(struct io_kiocb
*req
, unsigned int issue_flags
)
3480 struct io_rename
*ren
= &req
->rename
;
3483 if (issue_flags
& IO_URING_F_NONBLOCK
)
3486 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3487 ren
->newpath
, ren
->flags
);
3489 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3491 req_set_fail_links(req
);
3492 io_req_complete(req
, ret
);
3496 static int io_unlinkat_prep(struct io_kiocb
*req
,
3497 const struct io_uring_sqe
*sqe
)
3499 struct io_unlink
*un
= &req
->unlink
;
3500 const char __user
*fname
;
3502 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3505 un
->dfd
= READ_ONCE(sqe
->fd
);
3507 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3508 if (un
->flags
& ~AT_REMOVEDIR
)
3511 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3512 un
->filename
= getname(fname
);
3513 if (IS_ERR(un
->filename
))
3514 return PTR_ERR(un
->filename
);
3516 req
->flags
|= REQ_F_NEED_CLEANUP
;
3520 static int io_unlinkat(struct io_kiocb
*req
, unsigned int issue_flags
)
3522 struct io_unlink
*un
= &req
->unlink
;
3525 if (issue_flags
& IO_URING_F_NONBLOCK
)
3528 if (un
->flags
& AT_REMOVEDIR
)
3529 ret
= do_rmdir(un
->dfd
, un
->filename
);
3531 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3533 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3535 req_set_fail_links(req
);
3536 io_req_complete(req
, ret
);
3540 static int io_shutdown_prep(struct io_kiocb
*req
,
3541 const struct io_uring_sqe
*sqe
)
3543 #if defined(CONFIG_NET)
3544 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3546 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3550 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3557 static int io_shutdown(struct io_kiocb
*req
, unsigned int issue_flags
)
3559 #if defined(CONFIG_NET)
3560 struct socket
*sock
;
3563 if (issue_flags
& IO_URING_F_NONBLOCK
)
3566 sock
= sock_from_file(req
->file
);
3567 if (unlikely(!sock
))
3570 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3572 req_set_fail_links(req
);
3573 io_req_complete(req
, ret
);
3580 static int __io_splice_prep(struct io_kiocb
*req
,
3581 const struct io_uring_sqe
*sqe
)
3583 struct io_splice
* sp
= &req
->splice
;
3584 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3586 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3590 sp
->len
= READ_ONCE(sqe
->len
);
3591 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3593 if (unlikely(sp
->flags
& ~valid_flags
))
3596 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3597 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3600 req
->flags
|= REQ_F_NEED_CLEANUP
;
3604 static int io_tee_prep(struct io_kiocb
*req
,
3605 const struct io_uring_sqe
*sqe
)
3607 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3609 return __io_splice_prep(req
, sqe
);
3612 static int io_tee(struct io_kiocb
*req
, unsigned int issue_flags
)
3614 struct io_splice
*sp
= &req
->splice
;
3615 struct file
*in
= sp
->file_in
;
3616 struct file
*out
= sp
->file_out
;
3617 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3620 if (issue_flags
& IO_URING_F_NONBLOCK
)
3623 ret
= do_tee(in
, out
, sp
->len
, flags
);
3625 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
3627 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3630 req_set_fail_links(req
);
3631 io_req_complete(req
, ret
);
3635 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3637 struct io_splice
* sp
= &req
->splice
;
3639 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3640 sp
->off_out
= READ_ONCE(sqe
->off
);
3641 return __io_splice_prep(req
, sqe
);
3644 static int io_splice(struct io_kiocb
*req
, unsigned int issue_flags
)
3646 struct io_splice
*sp
= &req
->splice
;
3647 struct file
*in
= sp
->file_in
;
3648 struct file
*out
= sp
->file_out
;
3649 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3650 loff_t
*poff_in
, *poff_out
;
3653 if (issue_flags
& IO_URING_F_NONBLOCK
)
3656 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3657 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3660 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3662 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
3664 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3667 req_set_fail_links(req
);
3668 io_req_complete(req
, ret
);
3673 * IORING_OP_NOP just posts a completion event, nothing else.
3675 static int io_nop(struct io_kiocb
*req
, unsigned int issue_flags
)
3677 struct io_ring_ctx
*ctx
= req
->ctx
;
3679 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3682 __io_req_complete(req
, issue_flags
, 0, 0);
3686 static int io_fsync_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3688 struct io_ring_ctx
*ctx
= req
->ctx
;
3693 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3695 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3698 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3699 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3702 req
->sync
.off
= READ_ONCE(sqe
->off
);
3703 req
->sync
.len
= READ_ONCE(sqe
->len
);
3707 static int io_fsync(struct io_kiocb
*req
, unsigned int issue_flags
)
3709 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3712 /* fsync always requires a blocking context */
3713 if (issue_flags
& IO_URING_F_NONBLOCK
)
3716 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3717 end
> 0 ? end
: LLONG_MAX
,
3718 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3720 req_set_fail_links(req
);
3721 io_req_complete(req
, ret
);
3725 static int io_fallocate_prep(struct io_kiocb
*req
,
3726 const struct io_uring_sqe
*sqe
)
3728 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3730 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3733 req
->sync
.off
= READ_ONCE(sqe
->off
);
3734 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3735 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3739 static int io_fallocate(struct io_kiocb
*req
, unsigned int issue_flags
)
3743 /* fallocate always requiring blocking context */
3744 if (issue_flags
& IO_URING_F_NONBLOCK
)
3746 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3749 req_set_fail_links(req
);
3750 io_req_complete(req
, ret
);
3754 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3756 const char __user
*fname
;
3759 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3761 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3764 /* open.how should be already initialised */
3765 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3766 req
->open
.how
.flags
|= O_LARGEFILE
;
3768 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3769 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3770 req
->open
.filename
= getname(fname
);
3771 if (IS_ERR(req
->open
.filename
)) {
3772 ret
= PTR_ERR(req
->open
.filename
);
3773 req
->open
.filename
= NULL
;
3776 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3777 req
->flags
|= REQ_F_NEED_CLEANUP
;
3781 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3785 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3787 mode
= READ_ONCE(sqe
->len
);
3788 flags
= READ_ONCE(sqe
->open_flags
);
3789 req
->open
.how
= build_open_how(flags
, mode
);
3790 return __io_openat_prep(req
, sqe
);
3793 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3795 struct open_how __user
*how
;
3799 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3801 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3802 len
= READ_ONCE(sqe
->len
);
3803 if (len
< OPEN_HOW_SIZE_VER0
)
3806 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3811 return __io_openat_prep(req
, sqe
);
3814 static int io_openat2(struct io_kiocb
*req
, unsigned int issue_flags
)
3816 struct open_flags op
;
3819 bool resolve_nonblock
;
3822 ret
= build_open_flags(&req
->open
.how
, &op
);
3825 nonblock_set
= op
.open_flag
& O_NONBLOCK
;
3826 resolve_nonblock
= req
->open
.how
.resolve
& RESOLVE_CACHED
;
3827 if (issue_flags
& IO_URING_F_NONBLOCK
) {
3829 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
3830 * it'll always -EAGAIN
3832 if (req
->open
.how
.flags
& (O_TRUNC
| O_CREAT
| O_TMPFILE
))
3834 op
.lookup_flags
|= LOOKUP_CACHED
;
3835 op
.open_flag
|= O_NONBLOCK
;
3838 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3842 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3843 /* only retry if RESOLVE_CACHED wasn't already set by application */
3844 if ((!resolve_nonblock
&& (issue_flags
& IO_URING_F_NONBLOCK
)) &&
3845 file
== ERR_PTR(-EAGAIN
)) {
3847 * We could hang on to this 'fd', but seems like marginal
3848 * gain for something that is now known to be a slower path.
3849 * So just put it, and we'll get a new one when we retry.
3857 ret
= PTR_ERR(file
);
3859 if ((issue_flags
& IO_URING_F_NONBLOCK
) && !nonblock_set
)
3860 file
->f_flags
&= ~O_NONBLOCK
;
3861 fsnotify_open(file
);
3862 fd_install(ret
, file
);
3865 putname(req
->open
.filename
);
3866 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3868 req_set_fail_links(req
);
3869 io_req_complete(req
, ret
);
3873 static int io_openat(struct io_kiocb
*req
, unsigned int issue_flags
)
3875 return io_openat2(req
, issue_flags
);
3878 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3879 const struct io_uring_sqe
*sqe
)
3881 struct io_provide_buf
*p
= &req
->pbuf
;
3884 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3887 tmp
= READ_ONCE(sqe
->fd
);
3888 if (!tmp
|| tmp
> USHRT_MAX
)
3891 memset(p
, 0, sizeof(*p
));
3893 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3897 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3898 int bgid
, unsigned nbufs
)
3902 /* shouldn't happen */
3906 /* the head kbuf is the list itself */
3907 while (!list_empty(&buf
->list
)) {
3908 struct io_buffer
*nxt
;
3910 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3911 list_del(&nxt
->list
);
3918 xa_erase(&ctx
->io_buffers
, bgid
);
3923 static int io_remove_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
3925 struct io_provide_buf
*p
= &req
->pbuf
;
3926 struct io_ring_ctx
*ctx
= req
->ctx
;
3927 struct io_buffer
*head
;
3929 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3931 io_ring_submit_lock(ctx
, !force_nonblock
);
3933 lockdep_assert_held(&ctx
->uring_lock
);
3936 head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
3938 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3940 req_set_fail_links(req
);
3942 /* complete before unlock, IOPOLL may need the lock */
3943 __io_req_complete(req
, issue_flags
, ret
, 0);
3944 io_ring_submit_unlock(ctx
, !force_nonblock
);
3948 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3949 const struct io_uring_sqe
*sqe
)
3952 struct io_provide_buf
*p
= &req
->pbuf
;
3955 if (sqe
->ioprio
|| sqe
->rw_flags
)
3958 tmp
= READ_ONCE(sqe
->fd
);
3959 if (!tmp
|| tmp
> USHRT_MAX
)
3962 p
->addr
= READ_ONCE(sqe
->addr
);
3963 p
->len
= READ_ONCE(sqe
->len
);
3965 size
= (unsigned long)p
->len
* p
->nbufs
;
3966 if (!access_ok(u64_to_user_ptr(p
->addr
), size
))
3969 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3970 tmp
= READ_ONCE(sqe
->off
);
3971 if (tmp
> USHRT_MAX
)
3977 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3979 struct io_buffer
*buf
;
3980 u64 addr
= pbuf
->addr
;
3981 int i
, bid
= pbuf
->bid
;
3983 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3984 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3989 buf
->len
= pbuf
->len
;
3994 INIT_LIST_HEAD(&buf
->list
);
3997 list_add_tail(&buf
->list
, &(*head
)->list
);
4001 return i
? i
: -ENOMEM
;
4004 static int io_provide_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
4006 struct io_provide_buf
*p
= &req
->pbuf
;
4007 struct io_ring_ctx
*ctx
= req
->ctx
;
4008 struct io_buffer
*head
, *list
;
4010 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4012 io_ring_submit_lock(ctx
, !force_nonblock
);
4014 lockdep_assert_held(&ctx
->uring_lock
);
4016 list
= head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
4018 ret
= io_add_buffers(p
, &head
);
4019 if (ret
>= 0 && !list
) {
4020 ret
= xa_insert(&ctx
->io_buffers
, p
->bgid
, head
, GFP_KERNEL
);
4022 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4025 req_set_fail_links(req
);
4026 /* complete before unlock, IOPOLL may need the lock */
4027 __io_req_complete(req
, issue_flags
, ret
, 0);
4028 io_ring_submit_unlock(ctx
, !force_nonblock
);
4032 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4033 const struct io_uring_sqe
*sqe
)
4035 #if defined(CONFIG_EPOLL)
4036 if (sqe
->ioprio
|| sqe
->buf_index
)
4038 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4041 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4042 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4043 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4045 if (ep_op_has_event(req
->epoll
.op
)) {
4046 struct epoll_event __user
*ev
;
4048 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4049 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4059 static int io_epoll_ctl(struct io_kiocb
*req
, unsigned int issue_flags
)
4061 #if defined(CONFIG_EPOLL)
4062 struct io_epoll
*ie
= &req
->epoll
;
4064 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4066 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4067 if (force_nonblock
&& ret
== -EAGAIN
)
4071 req_set_fail_links(req
);
4072 __io_req_complete(req
, issue_flags
, ret
, 0);
4079 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4081 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4082 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4084 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
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
);
4096 static int io_madvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4098 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4099 struct io_madvise
*ma
= &req
->madvise
;
4102 if (issue_flags
& IO_URING_F_NONBLOCK
)
4105 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4107 req_set_fail_links(req
);
4108 io_req_complete(req
, ret
);
4115 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4117 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4119 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
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
);
4128 static int io_fadvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4130 struct io_fadvise
*fa
= &req
->fadvise
;
4133 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4134 switch (fa
->advice
) {
4135 case POSIX_FADV_NORMAL
:
4136 case POSIX_FADV_RANDOM
:
4137 case POSIX_FADV_SEQUENTIAL
:
4144 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4146 req_set_fail_links(req
);
4147 io_req_complete(req
, ret
);
4151 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4153 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4155 if (sqe
->ioprio
|| sqe
->buf_index
)
4157 if (req
->flags
& REQ_F_FIXED_FILE
)
4160 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4161 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4162 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4163 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4164 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4169 static int io_statx(struct io_kiocb
*req
, unsigned int issue_flags
)
4171 struct io_statx
*ctx
= &req
->statx
;
4174 if (issue_flags
& IO_URING_F_NONBLOCK
)
4177 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4181 req_set_fail_links(req
);
4182 io_req_complete(req
, ret
);
4186 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4188 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4190 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4191 sqe
->rw_flags
|| sqe
->buf_index
)
4193 if (req
->flags
& REQ_F_FIXED_FILE
)
4196 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4200 static int io_close(struct io_kiocb
*req
, unsigned int issue_flags
)
4202 struct files_struct
*files
= current
->files
;
4203 struct io_close
*close
= &req
->close
;
4204 struct fdtable
*fdt
;
4210 spin_lock(&files
->file_lock
);
4211 fdt
= files_fdtable(files
);
4212 if (close
->fd
>= fdt
->max_fds
) {
4213 spin_unlock(&files
->file_lock
);
4216 file
= fdt
->fd
[close
->fd
];
4218 spin_unlock(&files
->file_lock
);
4222 if (file
->f_op
== &io_uring_fops
) {
4223 spin_unlock(&files
->file_lock
);
4228 /* if the file has a flush method, be safe and punt to async */
4229 if (file
->f_op
->flush
&& (issue_flags
& IO_URING_F_NONBLOCK
)) {
4230 spin_unlock(&files
->file_lock
);
4234 ret
= __close_fd_get_file(close
->fd
, &file
);
4235 spin_unlock(&files
->file_lock
);
4242 /* No ->flush() or already async, safely close from here */
4243 ret
= filp_close(file
, current
->files
);
4246 req_set_fail_links(req
);
4249 __io_req_complete(req
, issue_flags
, ret
, 0);
4253 static int io_sfr_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4255 struct io_ring_ctx
*ctx
= req
->ctx
;
4257 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4259 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4262 req
->sync
.off
= READ_ONCE(sqe
->off
);
4263 req
->sync
.len
= READ_ONCE(sqe
->len
);
4264 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4268 static int io_sync_file_range(struct io_kiocb
*req
, unsigned int issue_flags
)
4272 /* sync_file_range always requires a blocking context */
4273 if (issue_flags
& IO_URING_F_NONBLOCK
)
4276 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4279 req_set_fail_links(req
);
4280 io_req_complete(req
, ret
);
4284 #if defined(CONFIG_NET)
4285 static int io_setup_async_msg(struct io_kiocb
*req
,
4286 struct io_async_msghdr
*kmsg
)
4288 struct io_async_msghdr
*async_msg
= req
->async_data
;
4292 if (io_alloc_async_data(req
)) {
4293 kfree(kmsg
->free_iov
);
4296 async_msg
= req
->async_data
;
4297 req
->flags
|= REQ_F_NEED_CLEANUP
;
4298 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4299 async_msg
->msg
.msg_name
= &async_msg
->addr
;
4300 /* if were using fast_iov, set it to the new one */
4301 if (!async_msg
->free_iov
)
4302 async_msg
->msg
.msg_iter
.iov
= async_msg
->fast_iov
;
4307 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4308 struct io_async_msghdr
*iomsg
)
4310 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4311 iomsg
->free_iov
= iomsg
->fast_iov
;
4312 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4313 req
->sr_msg
.msg_flags
, &iomsg
->free_iov
);
4316 static int io_sendmsg_prep_async(struct io_kiocb
*req
)
4320 ret
= io_sendmsg_copy_hdr(req
, req
->async_data
);
4322 req
->flags
|= REQ_F_NEED_CLEANUP
;
4326 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4328 struct io_sr_msg
*sr
= &req
->sr_msg
;
4330 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4333 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4334 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4335 sr
->len
= READ_ONCE(sqe
->len
);
4337 #ifdef CONFIG_COMPAT
4338 if (req
->ctx
->compat
)
4339 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4344 static int io_sendmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4346 struct io_async_msghdr iomsg
, *kmsg
;
4347 struct socket
*sock
;
4352 sock
= sock_from_file(req
->file
);
4353 if (unlikely(!sock
))
4356 kmsg
= req
->async_data
;
4358 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4364 flags
= req
->sr_msg
.msg_flags
| MSG_NOSIGNAL
;
4365 if (flags
& MSG_DONTWAIT
)
4366 req
->flags
|= REQ_F_NOWAIT
;
4367 else if (issue_flags
& IO_URING_F_NONBLOCK
)
4368 flags
|= MSG_DONTWAIT
;
4370 if (flags
& MSG_WAITALL
)
4371 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
4373 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4374 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4375 return io_setup_async_msg(req
, kmsg
);
4376 if (ret
== -ERESTARTSYS
)
4379 /* fast path, check for non-NULL to avoid function call */
4381 kfree(kmsg
->free_iov
);
4382 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4384 req_set_fail_links(req
);
4385 __io_req_complete(req
, issue_flags
, ret
, 0);
4389 static int io_send(struct io_kiocb
*req
, unsigned int issue_flags
)
4391 struct io_sr_msg
*sr
= &req
->sr_msg
;
4394 struct socket
*sock
;
4399 sock
= sock_from_file(req
->file
);
4400 if (unlikely(!sock
))
4403 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4407 msg
.msg_name
= NULL
;
4408 msg
.msg_control
= NULL
;
4409 msg
.msg_controllen
= 0;
4410 msg
.msg_namelen
= 0;
4412 flags
= req
->sr_msg
.msg_flags
| MSG_NOSIGNAL
;
4413 if (flags
& MSG_DONTWAIT
)
4414 req
->flags
|= REQ_F_NOWAIT
;
4415 else if (issue_flags
& IO_URING_F_NONBLOCK
)
4416 flags
|= MSG_DONTWAIT
;
4418 if (flags
& MSG_WAITALL
)
4419 min_ret
= iov_iter_count(&msg
.msg_iter
);
4421 msg
.msg_flags
= flags
;
4422 ret
= sock_sendmsg(sock
, &msg
);
4423 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4425 if (ret
== -ERESTARTSYS
)
4429 req_set_fail_links(req
);
4430 __io_req_complete(req
, issue_flags
, ret
, 0);
4434 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4435 struct io_async_msghdr
*iomsg
)
4437 struct io_sr_msg
*sr
= &req
->sr_msg
;
4438 struct iovec __user
*uiov
;
4442 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4443 &iomsg
->uaddr
, &uiov
, &iov_len
);
4447 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4450 if (copy_from_user(iomsg
->fast_iov
, uiov
, sizeof(*uiov
)))
4452 sr
->len
= iomsg
->fast_iov
[0].iov_len
;
4453 iomsg
->free_iov
= NULL
;
4455 iomsg
->free_iov
= iomsg
->fast_iov
;
4456 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4457 &iomsg
->free_iov
, &iomsg
->msg
.msg_iter
,
4466 #ifdef CONFIG_COMPAT
4467 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4468 struct io_async_msghdr
*iomsg
)
4470 struct compat_msghdr __user
*msg_compat
;
4471 struct io_sr_msg
*sr
= &req
->sr_msg
;
4472 struct compat_iovec __user
*uiov
;
4477 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4478 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4483 uiov
= compat_ptr(ptr
);
4484 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4485 compat_ssize_t clen
;
4489 if (!access_ok(uiov
, sizeof(*uiov
)))
4491 if (__get_user(clen
, &uiov
->iov_len
))
4496 iomsg
->free_iov
= NULL
;
4498 iomsg
->free_iov
= iomsg
->fast_iov
;
4499 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4500 UIO_FASTIOV
, &iomsg
->free_iov
,
4501 &iomsg
->msg
.msg_iter
, true);
4510 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4511 struct io_async_msghdr
*iomsg
)
4513 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4515 #ifdef CONFIG_COMPAT
4516 if (req
->ctx
->compat
)
4517 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4520 return __io_recvmsg_copy_hdr(req
, iomsg
);
4523 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4526 struct io_sr_msg
*sr
= &req
->sr_msg
;
4527 struct io_buffer
*kbuf
;
4529 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4534 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4538 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4540 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4543 static int io_recvmsg_prep_async(struct io_kiocb
*req
)
4547 ret
= io_recvmsg_copy_hdr(req
, req
->async_data
);
4549 req
->flags
|= REQ_F_NEED_CLEANUP
;
4553 static int io_recvmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4555 struct io_sr_msg
*sr
= &req
->sr_msg
;
4557 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4560 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4561 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4562 sr
->len
= READ_ONCE(sqe
->len
);
4563 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4565 #ifdef CONFIG_COMPAT
4566 if (req
->ctx
->compat
)
4567 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4572 static int io_recvmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4574 struct io_async_msghdr iomsg
, *kmsg
;
4575 struct socket
*sock
;
4576 struct io_buffer
*kbuf
;
4579 int ret
, cflags
= 0;
4580 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4582 sock
= sock_from_file(req
->file
);
4583 if (unlikely(!sock
))
4586 kmsg
= req
->async_data
;
4588 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4594 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4595 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4597 return PTR_ERR(kbuf
);
4598 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4599 kmsg
->fast_iov
[0].iov_len
= req
->sr_msg
.len
;
4600 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->fast_iov
,
4601 1, req
->sr_msg
.len
);
4604 flags
= req
->sr_msg
.msg_flags
| MSG_NOSIGNAL
;
4605 if (flags
& MSG_DONTWAIT
)
4606 req
->flags
|= REQ_F_NOWAIT
;
4607 else if (force_nonblock
)
4608 flags
|= MSG_DONTWAIT
;
4610 if (flags
& MSG_WAITALL
)
4611 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
4613 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4614 kmsg
->uaddr
, flags
);
4615 if (force_nonblock
&& ret
== -EAGAIN
)
4616 return io_setup_async_msg(req
, kmsg
);
4617 if (ret
== -ERESTARTSYS
)
4620 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4621 cflags
= io_put_recv_kbuf(req
);
4622 /* fast path, check for non-NULL to avoid function call */
4624 kfree(kmsg
->free_iov
);
4625 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4626 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (kmsg
->msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
4627 req_set_fail_links(req
);
4628 __io_req_complete(req
, issue_flags
, ret
, cflags
);
4632 static int io_recv(struct io_kiocb
*req
, unsigned int issue_flags
)
4634 struct io_buffer
*kbuf
;
4635 struct io_sr_msg
*sr
= &req
->sr_msg
;
4637 void __user
*buf
= sr
->buf
;
4638 struct socket
*sock
;
4642 int ret
, cflags
= 0;
4643 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4645 sock
= sock_from_file(req
->file
);
4646 if (unlikely(!sock
))
4649 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4650 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4652 return PTR_ERR(kbuf
);
4653 buf
= u64_to_user_ptr(kbuf
->addr
);
4656 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4660 msg
.msg_name
= NULL
;
4661 msg
.msg_control
= NULL
;
4662 msg
.msg_controllen
= 0;
4663 msg
.msg_namelen
= 0;
4664 msg
.msg_iocb
= NULL
;
4667 flags
= req
->sr_msg
.msg_flags
| MSG_NOSIGNAL
;
4668 if (flags
& MSG_DONTWAIT
)
4669 req
->flags
|= REQ_F_NOWAIT
;
4670 else if (force_nonblock
)
4671 flags
|= MSG_DONTWAIT
;
4673 if (flags
& MSG_WAITALL
)
4674 min_ret
= iov_iter_count(&msg
.msg_iter
);
4676 ret
= sock_recvmsg(sock
, &msg
, flags
);
4677 if (force_nonblock
&& ret
== -EAGAIN
)
4679 if (ret
== -ERESTARTSYS
)
4682 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4683 cflags
= io_put_recv_kbuf(req
);
4684 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
4685 req_set_fail_links(req
);
4686 __io_req_complete(req
, issue_flags
, ret
, cflags
);
4690 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4692 struct io_accept
*accept
= &req
->accept
;
4694 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4696 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4699 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4700 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4701 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4702 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4706 static int io_accept(struct io_kiocb
*req
, unsigned int issue_flags
)
4708 struct io_accept
*accept
= &req
->accept
;
4709 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4710 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4713 if (req
->file
->f_flags
& O_NONBLOCK
)
4714 req
->flags
|= REQ_F_NOWAIT
;
4716 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4717 accept
->addr_len
, accept
->flags
,
4719 if (ret
== -EAGAIN
&& force_nonblock
)
4722 if (ret
== -ERESTARTSYS
)
4724 req_set_fail_links(req
);
4726 __io_req_complete(req
, issue_flags
, ret
, 0);
4730 static int io_connect_prep_async(struct io_kiocb
*req
)
4732 struct io_async_connect
*io
= req
->async_data
;
4733 struct io_connect
*conn
= &req
->connect
;
4735 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
, &io
->address
);
4738 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4740 struct io_connect
*conn
= &req
->connect
;
4742 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4744 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4747 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4748 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4752 static int io_connect(struct io_kiocb
*req
, unsigned int issue_flags
)
4754 struct io_async_connect __io
, *io
;
4755 unsigned file_flags
;
4757 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4759 if (req
->async_data
) {
4760 io
= req
->async_data
;
4762 ret
= move_addr_to_kernel(req
->connect
.addr
,
4763 req
->connect
.addr_len
,
4770 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4772 ret
= __sys_connect_file(req
->file
, &io
->address
,
4773 req
->connect
.addr_len
, file_flags
);
4774 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4775 if (req
->async_data
)
4777 if (io_alloc_async_data(req
)) {
4781 memcpy(req
->async_data
, &__io
, sizeof(__io
));
4784 if (ret
== -ERESTARTSYS
)
4788 req_set_fail_links(req
);
4789 __io_req_complete(req
, issue_flags
, ret
, 0);
4792 #else /* !CONFIG_NET */
4793 #define IO_NETOP_FN(op) \
4794 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
4796 return -EOPNOTSUPP; \
4799 #define IO_NETOP_PREP(op) \
4801 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
4803 return -EOPNOTSUPP; \
4806 #define IO_NETOP_PREP_ASYNC(op) \
4808 static int io_##op##_prep_async(struct io_kiocb *req) \
4810 return -EOPNOTSUPP; \
4813 IO_NETOP_PREP_ASYNC(sendmsg
);
4814 IO_NETOP_PREP_ASYNC(recvmsg
);
4815 IO_NETOP_PREP_ASYNC(connect
);
4816 IO_NETOP_PREP(accept
);
4819 #endif /* CONFIG_NET */
4821 struct io_poll_table
{
4822 struct poll_table_struct pt
;
4823 struct io_kiocb
*req
;
4827 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4828 __poll_t mask
, task_work_func_t func
)
4832 /* for instances that support it check for an event match first: */
4833 if (mask
&& !(mask
& poll
->events
))
4836 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4838 list_del_init(&poll
->wait
.entry
);
4841 req
->task_work
.func
= func
;
4844 * If this fails, then the task is exiting. When a task exits, the
4845 * work gets canceled, so just cancel this request as well instead
4846 * of executing it. We can't safely execute it anyway, as we may not
4847 * have the needed state needed for it anyway.
4849 ret
= io_req_task_work_add(req
);
4850 if (unlikely(ret
)) {
4851 WRITE_ONCE(poll
->canceled
, true);
4852 io_req_task_work_add_fallback(req
, func
);
4857 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4858 __acquires(&req
->ctx
->completion_lock
)
4860 struct io_ring_ctx
*ctx
= req
->ctx
;
4862 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4863 struct poll_table_struct pt
= { ._key
= poll
->events
};
4865 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4868 spin_lock_irq(&ctx
->completion_lock
);
4869 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4870 add_wait_queue(poll
->head
, &poll
->wait
);
4877 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
4879 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
4880 if (req
->opcode
== IORING_OP_POLL_ADD
)
4881 return req
->async_data
;
4882 return req
->apoll
->double_poll
;
4885 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
4887 if (req
->opcode
== IORING_OP_POLL_ADD
)
4889 return &req
->apoll
->poll
;
4892 static void io_poll_remove_double(struct io_kiocb
*req
)
4894 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
4896 lockdep_assert_held(&req
->ctx
->completion_lock
);
4898 if (poll
&& poll
->head
) {
4899 struct wait_queue_head
*head
= poll
->head
;
4901 spin_lock(&head
->lock
);
4902 list_del_init(&poll
->wait
.entry
);
4903 if (poll
->wait
.private)
4906 spin_unlock(&head
->lock
);
4910 static bool io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4912 struct io_ring_ctx
*ctx
= req
->ctx
;
4913 unsigned flags
= IORING_CQE_F_MORE
;
4915 if (!error
&& req
->poll
.canceled
) {
4917 req
->poll
.events
|= EPOLLONESHOT
;
4920 error
= mangle_poll(mask
);
4921 if (req
->poll
.events
& EPOLLONESHOT
)
4923 if (!__io_cqring_fill_event(req
, error
, flags
)) {
4924 io_poll_remove_waitqs(req
);
4925 req
->poll
.done
= true;
4928 io_commit_cqring(ctx
);
4929 return !(flags
& IORING_CQE_F_MORE
);
4932 static void io_poll_task_func(struct callback_head
*cb
)
4934 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4935 struct io_ring_ctx
*ctx
= req
->ctx
;
4936 struct io_kiocb
*nxt
;
4938 if (io_poll_rewait(req
, &req
->poll
)) {
4939 spin_unlock_irq(&ctx
->completion_lock
);
4943 post_ev
= done
= io_poll_complete(req
, req
->result
, 0);
4945 hash_del(&req
->hash_node
);
4946 } else if (!(req
->poll
.events
& EPOLLONESHOT
)) {
4949 add_wait_queue(req
->poll
.head
, &req
->poll
.wait
);
4951 spin_unlock_irq(&ctx
->completion_lock
);
4954 io_cqring_ev_posted(ctx
);
4956 nxt
= io_put_req_find_next(req
);
4958 __io_req_task_submit(nxt
);
4963 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4964 int sync
, void *key
)
4966 struct io_kiocb
*req
= wait
->private;
4967 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
4968 __poll_t mask
= key_to_poll(key
);
4970 /* for instances that support it check for an event match first: */
4971 if (mask
&& !(mask
& poll
->events
))
4973 if (!(poll
->events
& EPOLLONESHOT
))
4974 return poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
4976 list_del_init(&wait
->entry
);
4978 if (poll
&& poll
->head
) {
4981 spin_lock(&poll
->head
->lock
);
4982 done
= list_empty(&poll
->wait
.entry
);
4984 list_del_init(&poll
->wait
.entry
);
4985 /* make sure double remove sees this as being gone */
4986 wait
->private = NULL
;
4987 spin_unlock(&poll
->head
->lock
);
4989 /* use wait func handler, so it matches the rq type */
4990 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
4997 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
4998 wait_queue_func_t wake_func
)
5002 poll
->canceled
= false;
5003 poll
->update_events
= poll
->update_user_data
= false;
5004 #define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
5005 /* mask in events that we always want/need */
5006 poll
->events
= events
| IO_POLL_UNMASK
;
5007 INIT_LIST_HEAD(&poll
->wait
.entry
);
5008 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5011 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5012 struct wait_queue_head
*head
,
5013 struct io_poll_iocb
**poll_ptr
)
5015 struct io_kiocb
*req
= pt
->req
;
5018 * If poll->head is already set, it's because the file being polled
5019 * uses multiple waitqueues for poll handling (eg one for read, one
5020 * for write). Setup a separate io_poll_iocb if this happens.
5022 if (unlikely(poll
->head
)) {
5023 struct io_poll_iocb
*poll_one
= poll
;
5025 /* already have a 2nd entry, fail a third attempt */
5027 pt
->error
= -EINVAL
;
5030 /* double add on the same waitqueue head, ignore */
5031 if (poll
->head
== head
)
5033 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5035 pt
->error
= -ENOMEM
;
5038 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5040 poll
->wait
.private = req
;
5047 if (poll
->events
& EPOLLEXCLUSIVE
)
5048 add_wait_queue_exclusive(head
, &poll
->wait
);
5050 add_wait_queue(head
, &poll
->wait
);
5053 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5054 struct poll_table_struct
*p
)
5056 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5057 struct async_poll
*apoll
= pt
->req
->apoll
;
5059 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5062 static void io_async_task_func(struct callback_head
*cb
)
5064 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5065 struct async_poll
*apoll
= req
->apoll
;
5066 struct io_ring_ctx
*ctx
= req
->ctx
;
5068 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5070 if (io_poll_rewait(req
, &apoll
->poll
)) {
5071 spin_unlock_irq(&ctx
->completion_lock
);
5075 /* If req is still hashed, it cannot have been canceled. Don't check. */
5076 if (hash_hashed(&req
->hash_node
))
5077 hash_del(&req
->hash_node
);
5079 io_poll_remove_double(req
);
5080 spin_unlock_irq(&ctx
->completion_lock
);
5082 if (!READ_ONCE(apoll
->poll
.canceled
))
5083 __io_req_task_submit(req
);
5085 io_req_complete_failed(req
, -ECANCELED
);
5087 kfree(apoll
->double_poll
);
5091 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5094 struct io_kiocb
*req
= wait
->private;
5095 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5097 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5100 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5103 static void io_poll_req_insert(struct io_kiocb
*req
)
5105 struct io_ring_ctx
*ctx
= req
->ctx
;
5106 struct hlist_head
*list
;
5108 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5109 hlist_add_head(&req
->hash_node
, list
);
5112 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5113 struct io_poll_iocb
*poll
,
5114 struct io_poll_table
*ipt
, __poll_t mask
,
5115 wait_queue_func_t wake_func
)
5116 __acquires(&ctx
->completion_lock
)
5118 struct io_ring_ctx
*ctx
= req
->ctx
;
5119 bool cancel
= false;
5121 INIT_HLIST_NODE(&req
->hash_node
);
5122 io_init_poll_iocb(poll
, mask
, wake_func
);
5123 poll
->file
= req
->file
;
5124 poll
->wait
.private = req
;
5126 ipt
->pt
._key
= mask
;
5128 ipt
->error
= -EINVAL
;
5130 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5132 spin_lock_irq(&ctx
->completion_lock
);
5133 if (likely(poll
->head
)) {
5134 spin_lock(&poll
->head
->lock
);
5135 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5141 if ((mask
&& (poll
->events
& EPOLLONESHOT
)) || ipt
->error
)
5142 list_del_init(&poll
->wait
.entry
);
5144 WRITE_ONCE(poll
->canceled
, true);
5145 else if (!poll
->done
) /* actually waiting for an event */
5146 io_poll_req_insert(req
);
5147 spin_unlock(&poll
->head
->lock
);
5153 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5155 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5156 struct io_ring_ctx
*ctx
= req
->ctx
;
5157 struct async_poll
*apoll
;
5158 struct io_poll_table ipt
;
5162 if (!req
->file
|| !file_can_poll(req
->file
))
5164 if (req
->flags
& REQ_F_POLLED
)
5168 else if (def
->pollout
)
5172 /* if we can't nonblock try, then no point in arming a poll handler */
5173 if (!io_file_supports_async(req
, rw
))
5176 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5177 if (unlikely(!apoll
))
5179 apoll
->double_poll
= NULL
;
5181 req
->flags
|= REQ_F_POLLED
;
5184 mask
= EPOLLONESHOT
;
5186 mask
|= POLLIN
| POLLRDNORM
;
5188 mask
|= POLLOUT
| POLLWRNORM
;
5190 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5191 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5192 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5195 mask
|= POLLERR
| POLLPRI
;
5197 ipt
.pt
._qproc
= io_async_queue_proc
;
5199 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5201 if (ret
|| ipt
.error
) {
5202 io_poll_remove_double(req
);
5203 spin_unlock_irq(&ctx
->completion_lock
);
5204 kfree(apoll
->double_poll
);
5208 spin_unlock_irq(&ctx
->completion_lock
);
5209 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5210 apoll
->poll
.events
);
5214 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5215 struct io_poll_iocb
*poll
, bool do_cancel
)
5217 bool do_complete
= false;
5221 spin_lock(&poll
->head
->lock
);
5223 WRITE_ONCE(poll
->canceled
, true);
5224 if (!list_empty(&poll
->wait
.entry
)) {
5225 list_del_init(&poll
->wait
.entry
);
5228 spin_unlock(&poll
->head
->lock
);
5229 hash_del(&req
->hash_node
);
5233 static bool io_poll_remove_waitqs(struct io_kiocb
*req
)
5237 io_poll_remove_double(req
);
5239 if (req
->opcode
== IORING_OP_POLL_ADD
) {
5240 do_complete
= __io_poll_remove_one(req
, &req
->poll
, true);
5242 struct async_poll
*apoll
= req
->apoll
;
5244 /* non-poll requests have submit ref still */
5245 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
, true);
5248 kfree(apoll
->double_poll
);
5256 static bool io_poll_remove_one(struct io_kiocb
*req
)
5260 do_complete
= io_poll_remove_waitqs(req
);
5262 io_cqring_fill_event(req
, -ECANCELED
);
5263 io_commit_cqring(req
->ctx
);
5264 req_set_fail_links(req
);
5265 io_put_req_deferred(req
, 1);
5272 * Returns true if we found and killed one or more poll requests
5274 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5275 struct files_struct
*files
)
5277 struct hlist_node
*tmp
;
5278 struct io_kiocb
*req
;
5281 spin_lock_irq(&ctx
->completion_lock
);
5282 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5283 struct hlist_head
*list
;
5285 list
= &ctx
->cancel_hash
[i
];
5286 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5287 if (io_match_task(req
, tsk
, files
))
5288 posted
+= io_poll_remove_one(req
);
5291 spin_unlock_irq(&ctx
->completion_lock
);
5294 io_cqring_ev_posted(ctx
);
5299 static struct io_kiocb
*io_poll_find(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5301 struct hlist_head
*list
;
5302 struct io_kiocb
*req
;
5304 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5305 hlist_for_each_entry(req
, list
, hash_node
) {
5306 if (sqe_addr
!= req
->user_data
)
5314 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5316 struct io_kiocb
*req
;
5318 req
= io_poll_find(ctx
, sqe_addr
);
5321 if (io_poll_remove_one(req
))
5327 static int io_poll_remove_prep(struct io_kiocb
*req
,
5328 const struct io_uring_sqe
*sqe
)
5330 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5332 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5336 req
->poll_remove
.addr
= READ_ONCE(sqe
->addr
);
5341 * Find a running poll command that matches one specified in sqe->addr,
5342 * and remove it if found.
5344 static int io_poll_remove(struct io_kiocb
*req
, unsigned int issue_flags
)
5346 struct io_ring_ctx
*ctx
= req
->ctx
;
5349 spin_lock_irq(&ctx
->completion_lock
);
5350 ret
= io_poll_cancel(ctx
, req
->poll_remove
.addr
);
5351 spin_unlock_irq(&ctx
->completion_lock
);
5354 req_set_fail_links(req
);
5355 io_req_complete(req
, ret
);
5359 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5362 struct io_kiocb
*req
= wait
->private;
5363 struct io_poll_iocb
*poll
= &req
->poll
;
5365 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5368 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5369 struct poll_table_struct
*p
)
5371 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5373 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5376 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5378 struct io_poll_iocb
*poll
= &req
->poll
;
5381 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5383 if (sqe
->ioprio
|| sqe
->buf_index
)
5385 flags
= READ_ONCE(sqe
->len
);
5386 if (flags
& ~(IORING_POLL_ADD_MULTI
| IORING_POLL_UPDATE_EVENTS
|
5387 IORING_POLL_UPDATE_USER_DATA
))
5389 events
= READ_ONCE(sqe
->poll32_events
);
5391 events
= swahw32(events
);
5393 if (!(flags
& IORING_POLL_ADD_MULTI
))
5394 events
|= EPOLLONESHOT
;
5395 poll
->update_events
= poll
->update_user_data
= false;
5396 if (flags
& IORING_POLL_UPDATE_EVENTS
) {
5397 poll
->update_events
= true;
5398 poll
->old_user_data
= READ_ONCE(sqe
->addr
);
5400 if (flags
& IORING_POLL_UPDATE_USER_DATA
) {
5401 poll
->update_user_data
= true;
5402 poll
->new_user_data
= READ_ONCE(sqe
->off
);
5404 if (!(poll
->update_events
|| poll
->update_user_data
) &&
5405 (sqe
->off
|| sqe
->addr
))
5407 poll
->events
= demangle_poll(events
) |
5408 (events
& (EPOLLEXCLUSIVE
|EPOLLONESHOT
));
5412 static int __io_poll_add(struct io_kiocb
*req
)
5414 struct io_poll_iocb
*poll
= &req
->poll
;
5415 struct io_ring_ctx
*ctx
= req
->ctx
;
5416 struct io_poll_table ipt
;
5419 ipt
.pt
._qproc
= io_poll_queue_proc
;
5421 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5424 if (mask
) { /* no async, we'd stolen it */
5426 io_poll_complete(req
, mask
, 0);
5428 spin_unlock_irq(&ctx
->completion_lock
);
5431 io_cqring_ev_posted(ctx
);
5432 if (poll
->events
& EPOLLONESHOT
)
5438 static int io_poll_update(struct io_kiocb
*req
)
5440 struct io_ring_ctx
*ctx
= req
->ctx
;
5441 struct io_kiocb
*preq
;
5444 spin_lock_irq(&ctx
->completion_lock
);
5445 preq
= io_poll_find(ctx
, req
->poll
.old_user_data
);
5449 } else if (preq
->opcode
!= IORING_OP_POLL_ADD
) {
5450 /* don't allow internal poll updates */
5454 if (!__io_poll_remove_one(preq
, &preq
->poll
, false)) {
5455 if (preq
->poll
.events
& EPOLLONESHOT
) {
5460 /* we now have a detached poll request. reissue. */
5463 spin_unlock_irq(&ctx
->completion_lock
);
5465 req_set_fail_links(req
);
5466 io_req_complete(req
, ret
);
5469 /* only mask one event flags, keep behavior flags */
5470 if (req
->poll
.update_events
) {
5471 preq
->poll
.events
&= ~0xffff;
5472 preq
->poll
.events
|= req
->poll
.events
& 0xffff;
5473 preq
->poll
.events
|= IO_POLL_UNMASK
;
5475 if (req
->poll
.update_user_data
)
5476 preq
->user_data
= req
->poll
.new_user_data
;
5478 /* complete update request, we're done with it */
5479 io_req_complete(req
, ret
);
5481 ret
= __io_poll_add(preq
);
5483 req_set_fail_links(preq
);
5484 io_req_complete(preq
, ret
);
5489 static int io_poll_add(struct io_kiocb
*req
, unsigned int issue_flags
)
5491 if (!req
->poll
.update_events
&& !req
->poll
.update_user_data
)
5492 return __io_poll_add(req
);
5493 return io_poll_update(req
);
5496 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5498 struct io_timeout_data
*data
= container_of(timer
,
5499 struct io_timeout_data
, timer
);
5500 struct io_kiocb
*req
= data
->req
;
5501 struct io_ring_ctx
*ctx
= req
->ctx
;
5502 unsigned long flags
;
5504 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5505 list_del_init(&req
->timeout
.list
);
5506 atomic_set(&req
->ctx
->cq_timeouts
,
5507 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5509 io_cqring_fill_event(req
, -ETIME
);
5510 io_commit_cqring(ctx
);
5511 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5513 io_cqring_ev_posted(ctx
);
5514 req_set_fail_links(req
);
5516 return HRTIMER_NORESTART
;
5519 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5522 struct io_timeout_data
*io
;
5523 struct io_kiocb
*req
;
5526 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5527 if (user_data
== req
->user_data
) {
5534 return ERR_PTR(ret
);
5536 io
= req
->async_data
;
5537 ret
= hrtimer_try_to_cancel(&io
->timer
);
5539 return ERR_PTR(-EALREADY
);
5540 list_del_init(&req
->timeout
.list
);
5544 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5546 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5549 return PTR_ERR(req
);
5551 req_set_fail_links(req
);
5552 io_cqring_fill_event(req
, -ECANCELED
);
5553 io_put_req_deferred(req
, 1);
5557 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
5558 struct timespec64
*ts
, enum hrtimer_mode mode
)
5560 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5561 struct io_timeout_data
*data
;
5564 return PTR_ERR(req
);
5566 req
->timeout
.off
= 0; /* noseq */
5567 data
= req
->async_data
;
5568 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
5569 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, mode
);
5570 data
->timer
.function
= io_timeout_fn
;
5571 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
5575 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5576 const struct io_uring_sqe
*sqe
)
5578 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5580 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5582 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5584 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5587 tr
->addr
= READ_ONCE(sqe
->addr
);
5588 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
5589 if (tr
->flags
& IORING_TIMEOUT_UPDATE
) {
5590 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE
|IORING_TIMEOUT_ABS
))
5592 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
5594 } else if (tr
->flags
) {
5595 /* timeout removal doesn't support flags */
5602 static inline enum hrtimer_mode
io_translate_timeout_mode(unsigned int flags
)
5604 return (flags
& IORING_TIMEOUT_ABS
) ? HRTIMER_MODE_ABS
5609 * Remove or update an existing timeout command
5611 static int io_timeout_remove(struct io_kiocb
*req
, unsigned int issue_flags
)
5613 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5614 struct io_ring_ctx
*ctx
= req
->ctx
;
5617 spin_lock_irq(&ctx
->completion_lock
);
5618 if (!(req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
))
5619 ret
= io_timeout_cancel(ctx
, tr
->addr
);
5621 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
,
5622 io_translate_timeout_mode(tr
->flags
));
5624 io_cqring_fill_event(req
, ret
);
5625 io_commit_cqring(ctx
);
5626 spin_unlock_irq(&ctx
->completion_lock
);
5627 io_cqring_ev_posted(ctx
);
5629 req_set_fail_links(req
);
5634 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5635 bool is_timeout_link
)
5637 struct io_timeout_data
*data
;
5639 u32 off
= READ_ONCE(sqe
->off
);
5641 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5643 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5645 if (off
&& is_timeout_link
)
5647 flags
= READ_ONCE(sqe
->timeout_flags
);
5648 if (flags
& ~IORING_TIMEOUT_ABS
)
5651 req
->timeout
.off
= off
;
5653 if (!req
->async_data
&& io_alloc_async_data(req
))
5656 data
= req
->async_data
;
5659 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5662 data
->mode
= io_translate_timeout_mode(flags
);
5663 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5664 if (is_timeout_link
)
5665 io_req_track_inflight(req
);
5669 static int io_timeout(struct io_kiocb
*req
, unsigned int issue_flags
)
5671 struct io_ring_ctx
*ctx
= req
->ctx
;
5672 struct io_timeout_data
*data
= req
->async_data
;
5673 struct list_head
*entry
;
5674 u32 tail
, off
= req
->timeout
.off
;
5676 spin_lock_irq(&ctx
->completion_lock
);
5679 * sqe->off holds how many events that need to occur for this
5680 * timeout event to be satisfied. If it isn't set, then this is
5681 * a pure timeout request, sequence isn't used.
5683 if (io_is_timeout_noseq(req
)) {
5684 entry
= ctx
->timeout_list
.prev
;
5688 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5689 req
->timeout
.target_seq
= tail
+ off
;
5691 /* Update the last seq here in case io_flush_timeouts() hasn't.
5692 * This is safe because ->completion_lock is held, and submissions
5693 * and completions are never mixed in the same ->completion_lock section.
5695 ctx
->cq_last_tm_flush
= tail
;
5698 * Insertion sort, ensuring the first entry in the list is always
5699 * the one we need first.
5701 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5702 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5705 if (io_is_timeout_noseq(nxt
))
5707 /* nxt.seq is behind @tail, otherwise would've been completed */
5708 if (off
>= nxt
->timeout
.target_seq
- tail
)
5712 list_add(&req
->timeout
.list
, entry
);
5713 data
->timer
.function
= io_timeout_fn
;
5714 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5715 spin_unlock_irq(&ctx
->completion_lock
);
5719 struct io_cancel_data
{
5720 struct io_ring_ctx
*ctx
;
5724 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5726 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5727 struct io_cancel_data
*cd
= data
;
5729 return req
->ctx
== cd
->ctx
&& req
->user_data
== cd
->user_data
;
5732 static int io_async_cancel_one(struct io_uring_task
*tctx
, u64 user_data
,
5733 struct io_ring_ctx
*ctx
)
5735 struct io_cancel_data data
= { .ctx
= ctx
, .user_data
= user_data
, };
5736 enum io_wq_cancel cancel_ret
;
5739 if (!tctx
|| !tctx
->io_wq
)
5742 cancel_ret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_cb
, &data
, false);
5743 switch (cancel_ret
) {
5744 case IO_WQ_CANCEL_OK
:
5747 case IO_WQ_CANCEL_RUNNING
:
5750 case IO_WQ_CANCEL_NOTFOUND
:
5758 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5759 struct io_kiocb
*req
, __u64 sqe_addr
,
5762 unsigned long flags
;
5765 ret
= io_async_cancel_one(req
->task
->io_uring
, sqe_addr
, ctx
);
5766 if (ret
!= -ENOENT
) {
5767 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5771 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5772 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5775 ret
= io_poll_cancel(ctx
, sqe_addr
);
5779 io_cqring_fill_event(req
, ret
);
5780 io_commit_cqring(ctx
);
5781 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5782 io_cqring_ev_posted(ctx
);
5785 req_set_fail_links(req
);
5789 static int io_async_cancel_prep(struct io_kiocb
*req
,
5790 const struct io_uring_sqe
*sqe
)
5792 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5794 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5796 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5799 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5803 static int io_async_cancel(struct io_kiocb
*req
, unsigned int issue_flags
)
5805 struct io_ring_ctx
*ctx
= req
->ctx
;
5806 u64 sqe_addr
= req
->cancel
.addr
;
5807 struct io_tctx_node
*node
;
5810 /* tasks should wait for their io-wq threads, so safe w/o sync */
5811 ret
= io_async_cancel_one(req
->task
->io_uring
, sqe_addr
, ctx
);
5812 spin_lock_irq(&ctx
->completion_lock
);
5815 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5818 ret
= io_poll_cancel(ctx
, sqe_addr
);
5821 spin_unlock_irq(&ctx
->completion_lock
);
5823 /* slow path, try all io-wq's */
5824 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
5826 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
5827 struct io_uring_task
*tctx
= node
->task
->io_uring
;
5829 if (!tctx
|| !tctx
->io_wq
)
5831 ret
= io_async_cancel_one(tctx
, req
->cancel
.addr
, ctx
);
5835 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
5837 spin_lock_irq(&ctx
->completion_lock
);
5839 io_cqring_fill_event(req
, ret
);
5840 io_commit_cqring(ctx
);
5841 spin_unlock_irq(&ctx
->completion_lock
);
5842 io_cqring_ev_posted(ctx
);
5845 req_set_fail_links(req
);
5850 static int io_rsrc_update_prep(struct io_kiocb
*req
,
5851 const struct io_uring_sqe
*sqe
)
5853 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
5855 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5857 if (sqe
->ioprio
|| sqe
->rw_flags
)
5860 req
->rsrc_update
.offset
= READ_ONCE(sqe
->off
);
5861 req
->rsrc_update
.nr_args
= READ_ONCE(sqe
->len
);
5862 if (!req
->rsrc_update
.nr_args
)
5864 req
->rsrc_update
.arg
= READ_ONCE(sqe
->addr
);
5868 static int io_files_update(struct io_kiocb
*req
, unsigned int issue_flags
)
5870 struct io_ring_ctx
*ctx
= req
->ctx
;
5871 struct io_uring_rsrc_update up
;
5874 if (issue_flags
& IO_URING_F_NONBLOCK
)
5877 up
.offset
= req
->rsrc_update
.offset
;
5878 up
.data
= req
->rsrc_update
.arg
;
5880 mutex_lock(&ctx
->uring_lock
);
5881 ret
= __io_sqe_files_update(ctx
, &up
, req
->rsrc_update
.nr_args
);
5882 mutex_unlock(&ctx
->uring_lock
);
5885 req_set_fail_links(req
);
5886 __io_req_complete(req
, issue_flags
, ret
, 0);
5890 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5892 switch (req
->opcode
) {
5895 case IORING_OP_READV
:
5896 case IORING_OP_READ_FIXED
:
5897 case IORING_OP_READ
:
5898 return io_read_prep(req
, sqe
);
5899 case IORING_OP_WRITEV
:
5900 case IORING_OP_WRITE_FIXED
:
5901 case IORING_OP_WRITE
:
5902 return io_write_prep(req
, sqe
);
5903 case IORING_OP_POLL_ADD
:
5904 return io_poll_add_prep(req
, sqe
);
5905 case IORING_OP_POLL_REMOVE
:
5906 return io_poll_remove_prep(req
, sqe
);
5907 case IORING_OP_FSYNC
:
5908 return io_fsync_prep(req
, sqe
);
5909 case IORING_OP_SYNC_FILE_RANGE
:
5910 return io_sfr_prep(req
, sqe
);
5911 case IORING_OP_SENDMSG
:
5912 case IORING_OP_SEND
:
5913 return io_sendmsg_prep(req
, sqe
);
5914 case IORING_OP_RECVMSG
:
5915 case IORING_OP_RECV
:
5916 return io_recvmsg_prep(req
, sqe
);
5917 case IORING_OP_CONNECT
:
5918 return io_connect_prep(req
, sqe
);
5919 case IORING_OP_TIMEOUT
:
5920 return io_timeout_prep(req
, sqe
, false);
5921 case IORING_OP_TIMEOUT_REMOVE
:
5922 return io_timeout_remove_prep(req
, sqe
);
5923 case IORING_OP_ASYNC_CANCEL
:
5924 return io_async_cancel_prep(req
, sqe
);
5925 case IORING_OP_LINK_TIMEOUT
:
5926 return io_timeout_prep(req
, sqe
, true);
5927 case IORING_OP_ACCEPT
:
5928 return io_accept_prep(req
, sqe
);
5929 case IORING_OP_FALLOCATE
:
5930 return io_fallocate_prep(req
, sqe
);
5931 case IORING_OP_OPENAT
:
5932 return io_openat_prep(req
, sqe
);
5933 case IORING_OP_CLOSE
:
5934 return io_close_prep(req
, sqe
);
5935 case IORING_OP_FILES_UPDATE
:
5936 return io_rsrc_update_prep(req
, sqe
);
5937 case IORING_OP_STATX
:
5938 return io_statx_prep(req
, sqe
);
5939 case IORING_OP_FADVISE
:
5940 return io_fadvise_prep(req
, sqe
);
5941 case IORING_OP_MADVISE
:
5942 return io_madvise_prep(req
, sqe
);
5943 case IORING_OP_OPENAT2
:
5944 return io_openat2_prep(req
, sqe
);
5945 case IORING_OP_EPOLL_CTL
:
5946 return io_epoll_ctl_prep(req
, sqe
);
5947 case IORING_OP_SPLICE
:
5948 return io_splice_prep(req
, sqe
);
5949 case IORING_OP_PROVIDE_BUFFERS
:
5950 return io_provide_buffers_prep(req
, sqe
);
5951 case IORING_OP_REMOVE_BUFFERS
:
5952 return io_remove_buffers_prep(req
, sqe
);
5954 return io_tee_prep(req
, sqe
);
5955 case IORING_OP_SHUTDOWN
:
5956 return io_shutdown_prep(req
, sqe
);
5957 case IORING_OP_RENAMEAT
:
5958 return io_renameat_prep(req
, sqe
);
5959 case IORING_OP_UNLINKAT
:
5960 return io_unlinkat_prep(req
, sqe
);
5963 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5968 static int io_req_prep_async(struct io_kiocb
*req
)
5970 if (!io_op_defs
[req
->opcode
].needs_async_setup
)
5972 if (WARN_ON_ONCE(req
->async_data
))
5974 if (io_alloc_async_data(req
))
5977 switch (req
->opcode
) {
5978 case IORING_OP_READV
:
5979 return io_rw_prep_async(req
, READ
);
5980 case IORING_OP_WRITEV
:
5981 return io_rw_prep_async(req
, WRITE
);
5982 case IORING_OP_SENDMSG
:
5983 return io_sendmsg_prep_async(req
);
5984 case IORING_OP_RECVMSG
:
5985 return io_recvmsg_prep_async(req
);
5986 case IORING_OP_CONNECT
:
5987 return io_connect_prep_async(req
);
5989 printk_once(KERN_WARNING
"io_uring: prep_async() bad opcode %d\n",
5994 static u32
io_get_sequence(struct io_kiocb
*req
)
5996 struct io_kiocb
*pos
;
5997 struct io_ring_ctx
*ctx
= req
->ctx
;
5998 u32 total_submitted
, nr_reqs
= 0;
6000 io_for_each_link(pos
, req
)
6003 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
6004 return total_submitted
- nr_reqs
;
6007 static int io_req_defer(struct io_kiocb
*req
)
6009 struct io_ring_ctx
*ctx
= req
->ctx
;
6010 struct io_defer_entry
*de
;
6014 /* Still need defer if there is pending req in defer list. */
6015 if (likely(list_empty_careful(&ctx
->defer_list
) &&
6016 !(req
->flags
& REQ_F_IO_DRAIN
)))
6019 seq
= io_get_sequence(req
);
6020 /* Still a chance to pass the sequence check */
6021 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
6024 ret
= io_req_prep_async(req
);
6027 io_prep_async_link(req
);
6028 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
6032 spin_lock_irq(&ctx
->completion_lock
);
6033 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
6034 spin_unlock_irq(&ctx
->completion_lock
);
6036 io_queue_async_work(req
);
6037 return -EIOCBQUEUED
;
6040 trace_io_uring_defer(ctx
, req
, req
->user_data
);
6043 list_add_tail(&de
->list
, &ctx
->defer_list
);
6044 spin_unlock_irq(&ctx
->completion_lock
);
6045 return -EIOCBQUEUED
;
6048 static void io_clean_op(struct io_kiocb
*req
)
6050 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6051 switch (req
->opcode
) {
6052 case IORING_OP_READV
:
6053 case IORING_OP_READ_FIXED
:
6054 case IORING_OP_READ
:
6055 kfree((void *)(unsigned long)req
->rw
.addr
);
6057 case IORING_OP_RECVMSG
:
6058 case IORING_OP_RECV
:
6059 kfree(req
->sr_msg
.kbuf
);
6062 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
6065 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6066 switch (req
->opcode
) {
6067 case IORING_OP_READV
:
6068 case IORING_OP_READ_FIXED
:
6069 case IORING_OP_READ
:
6070 case IORING_OP_WRITEV
:
6071 case IORING_OP_WRITE_FIXED
:
6072 case IORING_OP_WRITE
: {
6073 struct io_async_rw
*io
= req
->async_data
;
6075 kfree(io
->free_iovec
);
6078 case IORING_OP_RECVMSG
:
6079 case IORING_OP_SENDMSG
: {
6080 struct io_async_msghdr
*io
= req
->async_data
;
6082 kfree(io
->free_iov
);
6085 case IORING_OP_SPLICE
:
6087 if (!(req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
))
6088 io_put_file(req
->splice
.file_in
);
6090 case IORING_OP_OPENAT
:
6091 case IORING_OP_OPENAT2
:
6092 if (req
->open
.filename
)
6093 putname(req
->open
.filename
);
6095 case IORING_OP_RENAMEAT
:
6096 putname(req
->rename
.oldpath
);
6097 putname(req
->rename
.newpath
);
6099 case IORING_OP_UNLINKAT
:
6100 putname(req
->unlink
.filename
);
6103 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
6107 static int io_issue_sqe(struct io_kiocb
*req
, unsigned int issue_flags
)
6109 struct io_ring_ctx
*ctx
= req
->ctx
;
6110 const struct cred
*creds
= NULL
;
6113 if (req
->work
.creds
&& req
->work
.creds
!= current_cred())
6114 creds
= override_creds(req
->work
.creds
);
6116 switch (req
->opcode
) {
6118 ret
= io_nop(req
, issue_flags
);
6120 case IORING_OP_READV
:
6121 case IORING_OP_READ_FIXED
:
6122 case IORING_OP_READ
:
6123 ret
= io_read(req
, issue_flags
);
6125 case IORING_OP_WRITEV
:
6126 case IORING_OP_WRITE_FIXED
:
6127 case IORING_OP_WRITE
:
6128 ret
= io_write(req
, issue_flags
);
6130 case IORING_OP_FSYNC
:
6131 ret
= io_fsync(req
, issue_flags
);
6133 case IORING_OP_POLL_ADD
:
6134 ret
= io_poll_add(req
, issue_flags
);
6136 case IORING_OP_POLL_REMOVE
:
6137 ret
= io_poll_remove(req
, issue_flags
);
6139 case IORING_OP_SYNC_FILE_RANGE
:
6140 ret
= io_sync_file_range(req
, issue_flags
);
6142 case IORING_OP_SENDMSG
:
6143 ret
= io_sendmsg(req
, issue_flags
);
6145 case IORING_OP_SEND
:
6146 ret
= io_send(req
, issue_flags
);
6148 case IORING_OP_RECVMSG
:
6149 ret
= io_recvmsg(req
, issue_flags
);
6151 case IORING_OP_RECV
:
6152 ret
= io_recv(req
, issue_flags
);
6154 case IORING_OP_TIMEOUT
:
6155 ret
= io_timeout(req
, issue_flags
);
6157 case IORING_OP_TIMEOUT_REMOVE
:
6158 ret
= io_timeout_remove(req
, issue_flags
);
6160 case IORING_OP_ACCEPT
:
6161 ret
= io_accept(req
, issue_flags
);
6163 case IORING_OP_CONNECT
:
6164 ret
= io_connect(req
, issue_flags
);
6166 case IORING_OP_ASYNC_CANCEL
:
6167 ret
= io_async_cancel(req
, issue_flags
);
6169 case IORING_OP_FALLOCATE
:
6170 ret
= io_fallocate(req
, issue_flags
);
6172 case IORING_OP_OPENAT
:
6173 ret
= io_openat(req
, issue_flags
);
6175 case IORING_OP_CLOSE
:
6176 ret
= io_close(req
, issue_flags
);
6178 case IORING_OP_FILES_UPDATE
:
6179 ret
= io_files_update(req
, issue_flags
);
6181 case IORING_OP_STATX
:
6182 ret
= io_statx(req
, issue_flags
);
6184 case IORING_OP_FADVISE
:
6185 ret
= io_fadvise(req
, issue_flags
);
6187 case IORING_OP_MADVISE
:
6188 ret
= io_madvise(req
, issue_flags
);
6190 case IORING_OP_OPENAT2
:
6191 ret
= io_openat2(req
, issue_flags
);
6193 case IORING_OP_EPOLL_CTL
:
6194 ret
= io_epoll_ctl(req
, issue_flags
);
6196 case IORING_OP_SPLICE
:
6197 ret
= io_splice(req
, issue_flags
);
6199 case IORING_OP_PROVIDE_BUFFERS
:
6200 ret
= io_provide_buffers(req
, issue_flags
);
6202 case IORING_OP_REMOVE_BUFFERS
:
6203 ret
= io_remove_buffers(req
, issue_flags
);
6206 ret
= io_tee(req
, issue_flags
);
6208 case IORING_OP_SHUTDOWN
:
6209 ret
= io_shutdown(req
, issue_flags
);
6211 case IORING_OP_RENAMEAT
:
6212 ret
= io_renameat(req
, issue_flags
);
6214 case IORING_OP_UNLINKAT
:
6215 ret
= io_unlinkat(req
, issue_flags
);
6223 revert_creds(creds
);
6228 /* If the op doesn't have a file, we're not polling for it */
6229 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
6230 const bool in_async
= io_wq_current_is_worker();
6232 /* workqueue context doesn't hold uring_lock, grab it now */
6234 mutex_lock(&ctx
->uring_lock
);
6236 io_iopoll_req_issued(req
, in_async
);
6239 mutex_unlock(&ctx
->uring_lock
);
6245 static void io_wq_submit_work(struct io_wq_work
*work
)
6247 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6248 struct io_kiocb
*timeout
;
6251 timeout
= io_prep_linked_timeout(req
);
6253 io_queue_linked_timeout(timeout
);
6255 if (work
->flags
& IO_WQ_WORK_CANCEL
)
6260 ret
= io_issue_sqe(req
, 0);
6262 * We can get EAGAIN for polled IO even though we're
6263 * forcing a sync submission from here, since we can't
6264 * wait for request slots on the block side.
6272 /* avoid locking problems by failing it from a clean context */
6274 /* io-wq is going to take one down */
6276 io_req_task_queue_fail(req
, ret
);
6280 #define FFS_ASYNC_READ 0x1UL
6281 #define FFS_ASYNC_WRITE 0x2UL
6283 #define FFS_ISREG 0x4UL
6285 #define FFS_ISREG 0x0UL
6287 #define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
6289 static inline struct file
**io_fixed_file_slot(struct io_rsrc_data
*file_data
,
6292 struct fixed_rsrc_table
*table
;
6294 table
= &file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
6295 return &table
->files
[i
& IORING_FILE_TABLE_MASK
];
6298 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6301 struct file
**file_slot
= io_fixed_file_slot(ctx
->file_data
, index
);
6303 return (struct file
*) ((unsigned long) *file_slot
& FFS_MASK
);
6306 static struct file
*io_file_get(struct io_submit_state
*state
,
6307 struct io_kiocb
*req
, int fd
, bool fixed
)
6309 struct io_ring_ctx
*ctx
= req
->ctx
;
6313 unsigned long file_ptr
;
6315 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6317 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6318 file_ptr
= (unsigned long) *io_fixed_file_slot(ctx
->file_data
, fd
);
6319 file
= (struct file
*) (file_ptr
& FFS_MASK
);
6320 file_ptr
&= ~FFS_MASK
;
6321 /* mask in overlapping REQ_F and FFS bits */
6322 req
->flags
|= (file_ptr
<< REQ_F_ASYNC_READ_BIT
);
6323 io_req_set_rsrc_node(req
);
6325 trace_io_uring_file_get(ctx
, fd
);
6326 file
= __io_file_get(state
, fd
);
6328 /* we don't allow fixed io_uring files */
6329 if (file
&& unlikely(file
->f_op
== &io_uring_fops
))
6330 io_req_track_inflight(req
);
6336 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6338 struct io_timeout_data
*data
= container_of(timer
,
6339 struct io_timeout_data
, timer
);
6340 struct io_kiocb
*prev
, *req
= data
->req
;
6341 struct io_ring_ctx
*ctx
= req
->ctx
;
6342 unsigned long flags
;
6344 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6345 prev
= req
->timeout
.head
;
6346 req
->timeout
.head
= NULL
;
6349 * We don't expect the list to be empty, that will only happen if we
6350 * race with the completion of the linked work.
6352 if (prev
&& req_ref_inc_not_zero(prev
))
6353 io_remove_next_linked(prev
);
6356 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6359 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6360 io_put_req_deferred(prev
, 1);
6362 io_req_complete_post(req
, -ETIME
, 0);
6363 io_put_req_deferred(req
, 1);
6365 return HRTIMER_NORESTART
;
6368 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6370 struct io_ring_ctx
*ctx
= req
->ctx
;
6372 spin_lock_irq(&ctx
->completion_lock
);
6374 * If the back reference is NULL, then our linked request finished
6375 * before we got a chance to setup the timer
6377 if (req
->timeout
.head
) {
6378 struct io_timeout_data
*data
= req
->async_data
;
6380 data
->timer
.function
= io_link_timeout_fn
;
6381 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6384 spin_unlock_irq(&ctx
->completion_lock
);
6385 /* drop submission reference */
6389 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6391 struct io_kiocb
*nxt
= req
->link
;
6393 if (!nxt
|| (req
->flags
& REQ_F_LINK_TIMEOUT
) ||
6394 nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6397 nxt
->timeout
.head
= req
;
6398 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6399 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6403 static void __io_queue_sqe(struct io_kiocb
*req
)
6405 struct io_kiocb
*linked_timeout
= io_prep_linked_timeout(req
);
6408 ret
= io_issue_sqe(req
, IO_URING_F_NONBLOCK
|IO_URING_F_COMPLETE_DEFER
);
6411 * We async punt it if the file wasn't marked NOWAIT, or if the file
6412 * doesn't support non-blocking read/write attempts
6415 /* drop submission reference */
6416 if (req
->flags
& REQ_F_COMPLETE_INLINE
) {
6417 struct io_ring_ctx
*ctx
= req
->ctx
;
6418 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
6420 cs
->reqs
[cs
->nr
++] = req
;
6421 if (cs
->nr
== ARRAY_SIZE(cs
->reqs
))
6422 io_submit_flush_completions(cs
, ctx
);
6426 } else if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6427 if (!io_arm_poll_handler(req
)) {
6429 * Queued up for async execution, worker will release
6430 * submit reference when the iocb is actually submitted.
6432 io_queue_async_work(req
);
6435 io_req_complete_failed(req
, ret
);
6438 io_queue_linked_timeout(linked_timeout
);
6441 static void io_queue_sqe(struct io_kiocb
*req
)
6445 ret
= io_req_defer(req
);
6447 if (ret
!= -EIOCBQUEUED
) {
6449 io_req_complete_failed(req
, ret
);
6451 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6452 ret
= io_req_prep_async(req
);
6455 io_queue_async_work(req
);
6457 __io_queue_sqe(req
);
6462 * Check SQE restrictions (opcode and flags).
6464 * Returns 'true' if SQE is allowed, 'false' otherwise.
6466 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6467 struct io_kiocb
*req
,
6468 unsigned int sqe_flags
)
6470 if (!ctx
->restricted
)
6473 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6476 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6477 ctx
->restrictions
.sqe_flags_required
)
6480 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6481 ctx
->restrictions
.sqe_flags_required
))
6487 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6488 const struct io_uring_sqe
*sqe
)
6490 struct io_submit_state
*state
;
6491 unsigned int sqe_flags
;
6492 int personality
, ret
= 0;
6494 req
->opcode
= READ_ONCE(sqe
->opcode
);
6495 /* same numerical values with corresponding REQ_F_*, safe to copy */
6496 req
->flags
= sqe_flags
= READ_ONCE(sqe
->flags
);
6497 req
->user_data
= READ_ONCE(sqe
->user_data
);
6498 req
->async_data
= NULL
;
6502 req
->fixed_rsrc_refs
= NULL
;
6503 /* one is dropped after submission, the other at completion */
6504 atomic_set(&req
->refs
, 2);
6505 req
->task
= current
;
6507 req
->work
.creds
= NULL
;
6509 /* enforce forwards compatibility on users */
6510 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
)) {
6515 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6518 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6521 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6522 !io_op_defs
[req
->opcode
].buffer_select
)
6525 personality
= READ_ONCE(sqe
->personality
);
6527 req
->work
.creds
= xa_load(&ctx
->personalities
, personality
);
6528 if (!req
->work
.creds
)
6530 get_cred(req
->work
.creds
);
6532 state
= &ctx
->submit_state
;
6535 * Plug now if we have more than 1 IO left after this, and the target
6536 * is potentially a read/write to block based storage.
6538 if (!state
->plug_started
&& state
->ios_left
> 1 &&
6539 io_op_defs
[req
->opcode
].plug
) {
6540 blk_start_plug(&state
->plug
);
6541 state
->plug_started
= true;
6544 if (io_op_defs
[req
->opcode
].needs_file
) {
6545 bool fixed
= req
->flags
& REQ_F_FIXED_FILE
;
6547 req
->file
= io_file_get(state
, req
, READ_ONCE(sqe
->fd
), fixed
);
6548 if (unlikely(!req
->file
))
6556 static int io_submit_sqe(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6557 const struct io_uring_sqe
*sqe
)
6559 struct io_submit_link
*link
= &ctx
->submit_state
.link
;
6562 ret
= io_init_req(ctx
, req
, sqe
);
6563 if (unlikely(ret
)) {
6566 /* fail even hard links since we don't submit */
6567 link
->head
->flags
|= REQ_F_FAIL_LINK
;
6568 io_req_complete_failed(link
->head
, -ECANCELED
);
6571 io_req_complete_failed(req
, ret
);
6574 ret
= io_req_prep(req
, sqe
);
6578 /* don't need @sqe from now on */
6579 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6580 true, ctx
->flags
& IORING_SETUP_SQPOLL
);
6583 * If we already have a head request, queue this one for async
6584 * submittal once the head completes. If we don't have a head but
6585 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6586 * submitted sync once the chain is complete. If none of those
6587 * conditions are true (normal request), then just queue it.
6590 struct io_kiocb
*head
= link
->head
;
6593 * Taking sequential execution of a link, draining both sides
6594 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6595 * requests in the link. So, it drains the head and the
6596 * next after the link request. The last one is done via
6597 * drain_next flag to persist the effect across calls.
6599 if (req
->flags
& REQ_F_IO_DRAIN
) {
6600 head
->flags
|= REQ_F_IO_DRAIN
;
6601 ctx
->drain_next
= 1;
6603 ret
= io_req_prep_async(req
);
6606 trace_io_uring_link(ctx
, req
, head
);
6607 link
->last
->link
= req
;
6610 /* last request of a link, enqueue the link */
6611 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6616 if (unlikely(ctx
->drain_next
)) {
6617 req
->flags
|= REQ_F_IO_DRAIN
;
6618 ctx
->drain_next
= 0;
6620 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6632 * Batched submission is done, ensure local IO is flushed out.
6634 static void io_submit_state_end(struct io_submit_state
*state
,
6635 struct io_ring_ctx
*ctx
)
6637 if (state
->link
.head
)
6638 io_queue_sqe(state
->link
.head
);
6640 io_submit_flush_completions(&state
->comp
, ctx
);
6641 if (state
->plug_started
)
6642 blk_finish_plug(&state
->plug
);
6643 io_state_file_put(state
);
6647 * Start submission side cache.
6649 static void io_submit_state_start(struct io_submit_state
*state
,
6650 unsigned int max_ios
)
6652 state
->plug_started
= false;
6653 state
->ios_left
= max_ios
;
6654 /* set only head, no need to init link_last in advance */
6655 state
->link
.head
= NULL
;
6658 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6660 struct io_rings
*rings
= ctx
->rings
;
6663 * Ensure any loads from the SQEs are done at this point,
6664 * since once we write the new head, the application could
6665 * write new data to them.
6667 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6671 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6672 * that is mapped by userspace. This means that care needs to be taken to
6673 * ensure that reads are stable, as we cannot rely on userspace always
6674 * being a good citizen. If members of the sqe are validated and then later
6675 * used, it's important that those reads are done through READ_ONCE() to
6676 * prevent a re-load down the line.
6678 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6680 u32
*sq_array
= ctx
->sq_array
;
6684 * The cached sq head (or cq tail) serves two purposes:
6686 * 1) allows us to batch the cost of updating the user visible
6688 * 2) allows the kernel side to track the head on its own, even
6689 * though the application is the one updating it.
6691 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
++ & ctx
->sq_mask
]);
6692 if (likely(head
< ctx
->sq_entries
))
6693 return &ctx
->sq_sqes
[head
];
6695 /* drop invalid entries */
6696 ctx
->cached_sq_dropped
++;
6697 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6701 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6705 /* if we have a backlog and couldn't flush it all, return BUSY */
6706 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6707 if (!__io_cqring_overflow_flush(ctx
, false))
6711 /* make sure SQ entry isn't read before tail */
6712 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6714 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6717 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6718 refcount_add(nr
, ¤t
->usage
);
6719 io_submit_state_start(&ctx
->submit_state
, nr
);
6721 while (submitted
< nr
) {
6722 const struct io_uring_sqe
*sqe
;
6723 struct io_kiocb
*req
;
6725 req
= io_alloc_req(ctx
);
6726 if (unlikely(!req
)) {
6728 submitted
= -EAGAIN
;
6731 sqe
= io_get_sqe(ctx
);
6732 if (unlikely(!sqe
)) {
6733 kmem_cache_free(req_cachep
, req
);
6736 /* will complete beyond this point, count as submitted */
6738 if (io_submit_sqe(ctx
, req
, sqe
))
6742 if (unlikely(submitted
!= nr
)) {
6743 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6744 struct io_uring_task
*tctx
= current
->io_uring
;
6745 int unused
= nr
- ref_used
;
6747 percpu_ref_put_many(&ctx
->refs
, unused
);
6748 percpu_counter_sub(&tctx
->inflight
, unused
);
6749 put_task_struct_many(current
, unused
);
6752 io_submit_state_end(&ctx
->submit_state
, ctx
);
6753 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6754 io_commit_sqring(ctx
);
6759 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6761 /* Tell userspace we may need a wakeup call */
6762 spin_lock_irq(&ctx
->completion_lock
);
6763 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6764 spin_unlock_irq(&ctx
->completion_lock
);
6767 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6769 spin_lock_irq(&ctx
->completion_lock
);
6770 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6771 spin_unlock_irq(&ctx
->completion_lock
);
6774 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
6776 unsigned int to_submit
;
6779 to_submit
= io_sqring_entries(ctx
);
6780 /* if we're handling multiple rings, cap submit size for fairness */
6781 if (cap_entries
&& to_submit
> 8)
6784 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
6785 unsigned nr_events
= 0;
6787 mutex_lock(&ctx
->uring_lock
);
6788 if (!list_empty(&ctx
->iopoll_list
))
6789 io_do_iopoll(ctx
, &nr_events
, 0);
6791 if (to_submit
&& likely(!percpu_ref_is_dying(&ctx
->refs
)) &&
6792 !(ctx
->flags
& IORING_SETUP_R_DISABLED
))
6793 ret
= io_submit_sqes(ctx
, to_submit
);
6794 mutex_unlock(&ctx
->uring_lock
);
6797 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
6798 wake_up(&ctx
->sqo_sq_wait
);
6803 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
6805 struct io_ring_ctx
*ctx
;
6806 unsigned sq_thread_idle
= 0;
6808 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6809 sq_thread_idle
= max(sq_thread_idle
, ctx
->sq_thread_idle
);
6810 sqd
->sq_thread_idle
= sq_thread_idle
;
6813 static int io_sq_thread(void *data
)
6815 struct io_sq_data
*sqd
= data
;
6816 struct io_ring_ctx
*ctx
;
6817 unsigned long timeout
= 0;
6818 char buf
[TASK_COMM_LEN
];
6821 snprintf(buf
, sizeof(buf
), "iou-sqp-%d", sqd
->task_pid
);
6822 set_task_comm(current
, buf
);
6823 current
->pf_io_worker
= NULL
;
6825 if (sqd
->sq_cpu
!= -1)
6826 set_cpus_allowed_ptr(current
, cpumask_of(sqd
->sq_cpu
));
6828 set_cpus_allowed_ptr(current
, cpu_online_mask
);
6829 current
->flags
|= PF_NO_SETAFFINITY
;
6831 mutex_lock(&sqd
->lock
);
6832 while (!test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
)) {
6834 bool cap_entries
, sqt_spin
, needs_sched
;
6836 if (test_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
) ||
6837 signal_pending(current
)) {
6838 bool did_sig
= false;
6840 mutex_unlock(&sqd
->lock
);
6841 if (signal_pending(current
)) {
6842 struct ksignal ksig
;
6844 did_sig
= get_signal(&ksig
);
6847 mutex_lock(&sqd
->lock
);
6851 io_run_task_work_head(&sqd
->park_task_work
);
6852 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6856 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
6857 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6858 const struct cred
*creds
= NULL
;
6860 if (ctx
->sq_creds
!= current_cred())
6861 creds
= override_creds(ctx
->sq_creds
);
6862 ret
= __io_sq_thread(ctx
, cap_entries
);
6864 revert_creds(creds
);
6865 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
6869 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
6873 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6878 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
6879 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6880 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6881 !list_empty_careful(&ctx
->iopoll_list
)) {
6882 needs_sched
= false;
6885 if (io_sqring_entries(ctx
)) {
6886 needs_sched
= false;
6891 if (needs_sched
&& !test_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
)) {
6892 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6893 io_ring_set_wakeup_flag(ctx
);
6895 mutex_unlock(&sqd
->lock
);
6897 mutex_lock(&sqd
->lock
);
6898 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6899 io_ring_clear_wakeup_flag(ctx
);
6902 finish_wait(&sqd
->wait
, &wait
);
6903 io_run_task_work_head(&sqd
->park_task_work
);
6904 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6907 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6908 io_uring_cancel_sqpoll(ctx
);
6910 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6911 io_ring_set_wakeup_flag(ctx
);
6912 mutex_unlock(&sqd
->lock
);
6915 io_run_task_work_head(&sqd
->park_task_work
);
6916 complete(&sqd
->exited
);
6920 struct io_wait_queue
{
6921 struct wait_queue_entry wq
;
6922 struct io_ring_ctx
*ctx
;
6924 unsigned nr_timeouts
;
6927 static inline bool io_should_wake(struct io_wait_queue
*iowq
)
6929 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6932 * Wake up if we have enough events, or if a timeout occurred since we
6933 * started waiting. For timeouts, we always want to return to userspace,
6934 * regardless of event count.
6936 return io_cqring_events(ctx
) >= iowq
->to_wait
||
6937 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6940 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6941 int wake_flags
, void *key
)
6943 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6947 * Cannot safely flush overflowed CQEs from here, ensure we wake up
6948 * the task, and the next invocation will do it.
6950 if (io_should_wake(iowq
) || test_bit(0, &iowq
->ctx
->cq_check_overflow
))
6951 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6955 static int io_run_task_work_sig(void)
6957 if (io_run_task_work())
6959 if (!signal_pending(current
))
6961 if (test_thread_flag(TIF_NOTIFY_SIGNAL
))
6962 return -ERESTARTSYS
;
6966 /* when returns >0, the caller should retry */
6967 static inline int io_cqring_wait_schedule(struct io_ring_ctx
*ctx
,
6968 struct io_wait_queue
*iowq
,
6969 signed long *timeout
)
6973 /* make sure we run task_work before checking for signals */
6974 ret
= io_run_task_work_sig();
6975 if (ret
|| io_should_wake(iowq
))
6977 /* let the caller flush overflows, retry */
6978 if (test_bit(0, &ctx
->cq_check_overflow
))
6981 *timeout
= schedule_timeout(*timeout
);
6982 return !*timeout
? -ETIME
: 1;
6986 * Wait until events become available, if we don't already have some. The
6987 * application must reap them itself, as they reside on the shared cq ring.
6989 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6990 const sigset_t __user
*sig
, size_t sigsz
,
6991 struct __kernel_timespec __user
*uts
)
6993 struct io_wait_queue iowq
= {
6996 .func
= io_wake_function
,
6997 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
7000 .to_wait
= min_events
,
7002 struct io_rings
*rings
= ctx
->rings
;
7003 signed long timeout
= MAX_SCHEDULE_TIMEOUT
;
7007 io_cqring_overflow_flush(ctx
, false);
7008 if (io_cqring_events(ctx
) >= min_events
)
7010 if (!io_run_task_work())
7015 #ifdef CONFIG_COMPAT
7016 if (in_compat_syscall())
7017 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
7021 ret
= set_user_sigmask(sig
, sigsz
);
7028 struct timespec64 ts
;
7030 if (get_timespec64(&ts
, uts
))
7032 timeout
= timespec64_to_jiffies(&ts
);
7035 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
7036 trace_io_uring_cqring_wait(ctx
, min_events
);
7038 /* if we can't even flush overflow, don't wait for more */
7039 if (!io_cqring_overflow_flush(ctx
, false)) {
7043 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
7044 TASK_INTERRUPTIBLE
);
7045 ret
= io_cqring_wait_schedule(ctx
, &iowq
, &timeout
);
7046 finish_wait(&ctx
->wait
, &iowq
.wq
);
7050 restore_saved_sigmask_unless(ret
== -EINTR
);
7052 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7055 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7057 #if defined(CONFIG_UNIX)
7058 if (ctx
->ring_sock
) {
7059 struct sock
*sock
= ctx
->ring_sock
->sk
;
7060 struct sk_buff
*skb
;
7062 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7068 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7071 file
= io_file_from_index(ctx
, i
);
7078 static void io_rsrc_data_ref_zero(struct percpu_ref
*ref
)
7080 struct io_rsrc_data
*data
= container_of(ref
, struct io_rsrc_data
, refs
);
7082 complete(&data
->done
);
7085 static inline void io_rsrc_ref_lock(struct io_ring_ctx
*ctx
)
7087 spin_lock_bh(&ctx
->rsrc_ref_lock
);
7090 static inline void io_rsrc_ref_unlock(struct io_ring_ctx
*ctx
)
7092 spin_unlock_bh(&ctx
->rsrc_ref_lock
);
7095 static void io_rsrc_node_set(struct io_ring_ctx
*ctx
,
7096 struct io_rsrc_data
*rsrc_data
,
7097 struct io_rsrc_node
*rsrc_node
)
7099 io_rsrc_ref_lock(ctx
);
7100 rsrc_data
->node
= rsrc_node
;
7101 list_add_tail(&rsrc_node
->node
, &ctx
->rsrc_ref_list
);
7102 io_rsrc_ref_unlock(ctx
);
7103 percpu_ref_get(&rsrc_data
->refs
);
7106 static void io_rsrc_node_kill(struct io_ring_ctx
*ctx
, struct io_rsrc_data
*data
)
7108 struct io_rsrc_node
*ref_node
= NULL
;
7110 io_rsrc_ref_lock(ctx
);
7111 ref_node
= data
->node
;
7113 io_rsrc_ref_unlock(ctx
);
7115 percpu_ref_kill(&ref_node
->refs
);
7118 static int io_rsrc_node_prealloc(struct io_ring_ctx
*ctx
)
7120 if (ctx
->rsrc_backup_node
)
7122 ctx
->rsrc_backup_node
= io_rsrc_node_alloc(ctx
);
7123 return ctx
->rsrc_backup_node
? 0 : -ENOMEM
;
7126 static struct io_rsrc_node
*
7127 io_rsrc_node_get(struct io_ring_ctx
*ctx
,
7128 struct io_rsrc_data
*rsrc_data
,
7129 void (*rsrc_put
)(struct io_ring_ctx
*ctx
,
7130 struct io_rsrc_put
*prsrc
))
7132 struct io_rsrc_node
*node
= ctx
->rsrc_backup_node
;
7134 WARN_ON_ONCE(!node
);
7136 ctx
->rsrc_backup_node
= NULL
;
7137 node
->rsrc_data
= rsrc_data
;
7138 node
->rsrc_put
= rsrc_put
;
7142 static int io_rsrc_ref_quiesce(struct io_rsrc_data
*data
,
7143 struct io_ring_ctx
*ctx
,
7144 void (*rsrc_put
)(struct io_ring_ctx
*ctx
,
7145 struct io_rsrc_put
*prsrc
))
7147 struct io_rsrc_node
*node
;
7153 data
->quiesce
= true;
7155 ret
= io_rsrc_node_prealloc(ctx
);
7158 io_rsrc_node_kill(ctx
, data
);
7159 percpu_ref_kill(&data
->refs
);
7160 flush_delayed_work(&ctx
->rsrc_put_work
);
7162 ret
= wait_for_completion_interruptible(&data
->done
);
7166 percpu_ref_resurrect(&data
->refs
);
7167 node
= io_rsrc_node_get(ctx
, data
, rsrc_put
);
7168 io_rsrc_node_set(ctx
, data
, node
);
7169 reinit_completion(&data
->done
);
7171 mutex_unlock(&ctx
->uring_lock
);
7172 ret
= io_run_task_work_sig();
7173 mutex_lock(&ctx
->uring_lock
);
7175 data
->quiesce
= false;
7180 static struct io_rsrc_data
*io_rsrc_data_alloc(struct io_ring_ctx
*ctx
)
7182 struct io_rsrc_data
*data
;
7184 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
7188 if (percpu_ref_init(&data
->refs
, io_rsrc_data_ref_zero
,
7189 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
)) {
7194 init_completion(&data
->done
);
7198 static void io_rsrc_data_free(struct io_rsrc_data
*data
)
7200 percpu_ref_exit(&data
->refs
);
7205 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7207 struct io_rsrc_data
*data
= ctx
->file_data
;
7208 unsigned nr_tables
, i
;
7212 * percpu_ref_is_dying() is to stop parallel files unregister
7213 * Since we possibly drop uring lock later in this function to
7216 if (!data
|| percpu_ref_is_dying(&data
->refs
))
7218 ret
= io_rsrc_ref_quiesce(data
, ctx
, io_ring_file_put
);
7222 __io_sqe_files_unregister(ctx
);
7223 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
7224 for (i
= 0; i
< nr_tables
; i
++)
7225 kfree(data
->table
[i
].files
);
7226 io_rsrc_data_free(data
);
7227 ctx
->file_data
= NULL
;
7228 ctx
->nr_user_files
= 0;
7232 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7233 __releases(&sqd
->lock
)
7235 WARN_ON_ONCE(sqd
->thread
== current
);
7238 * Do the dance but not conditional clear_bit() because it'd race with
7239 * other threads incrementing park_pending and setting the bit.
7241 clear_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7242 if (atomic_dec_return(&sqd
->park_pending
))
7243 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7244 mutex_unlock(&sqd
->lock
);
7247 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7248 __acquires(&sqd
->lock
)
7250 WARN_ON_ONCE(sqd
->thread
== current
);
7252 atomic_inc(&sqd
->park_pending
);
7253 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7254 mutex_lock(&sqd
->lock
);
7256 wake_up_process(sqd
->thread
);
7259 static void io_sq_thread_stop(struct io_sq_data
*sqd
)
7261 WARN_ON_ONCE(sqd
->thread
== current
);
7263 mutex_lock(&sqd
->lock
);
7264 set_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
);
7266 wake_up_process(sqd
->thread
);
7267 mutex_unlock(&sqd
->lock
);
7268 wait_for_completion(&sqd
->exited
);
7271 static void io_put_sq_data(struct io_sq_data
*sqd
)
7273 if (refcount_dec_and_test(&sqd
->refs
)) {
7274 WARN_ON_ONCE(atomic_read(&sqd
->park_pending
));
7276 io_sq_thread_stop(sqd
);
7281 static void io_sq_thread_finish(struct io_ring_ctx
*ctx
)
7283 struct io_sq_data
*sqd
= ctx
->sq_data
;
7286 io_sq_thread_park(sqd
);
7287 list_del_init(&ctx
->sqd_list
);
7288 io_sqd_update_thread_idle(sqd
);
7289 io_sq_thread_unpark(sqd
);
7291 io_put_sq_data(sqd
);
7292 ctx
->sq_data
= NULL
;
7294 put_cred(ctx
->sq_creds
);
7298 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7300 struct io_ring_ctx
*ctx_attach
;
7301 struct io_sq_data
*sqd
;
7304 f
= fdget(p
->wq_fd
);
7306 return ERR_PTR(-ENXIO
);
7307 if (f
.file
->f_op
!= &io_uring_fops
) {
7309 return ERR_PTR(-EINVAL
);
7312 ctx_attach
= f
.file
->private_data
;
7313 sqd
= ctx_attach
->sq_data
;
7316 return ERR_PTR(-EINVAL
);
7318 if (sqd
->task_tgid
!= current
->tgid
) {
7320 return ERR_PTR(-EPERM
);
7323 refcount_inc(&sqd
->refs
);
7328 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
,
7331 struct io_sq_data
*sqd
;
7334 if (p
->flags
& IORING_SETUP_ATTACH_WQ
) {
7335 sqd
= io_attach_sq_data(p
);
7340 /* fall through for EPERM case, setup new sqd/task */
7341 if (PTR_ERR(sqd
) != -EPERM
)
7345 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7347 return ERR_PTR(-ENOMEM
);
7349 atomic_set(&sqd
->park_pending
, 0);
7350 refcount_set(&sqd
->refs
, 1);
7351 INIT_LIST_HEAD(&sqd
->ctx_list
);
7352 mutex_init(&sqd
->lock
);
7353 init_waitqueue_head(&sqd
->wait
);
7354 init_completion(&sqd
->exited
);
7358 #if defined(CONFIG_UNIX)
7360 * Ensure the UNIX gc is aware of our file set, so we are certain that
7361 * the io_uring can be safely unregistered on process exit, even if we have
7362 * loops in the file referencing.
7364 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7366 struct sock
*sk
= ctx
->ring_sock
->sk
;
7367 struct scm_fp_list
*fpl
;
7368 struct sk_buff
*skb
;
7371 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7375 skb
= alloc_skb(0, GFP_KERNEL
);
7384 fpl
->user
= get_uid(current_user());
7385 for (i
= 0; i
< nr
; i
++) {
7386 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7390 fpl
->fp
[nr_files
] = get_file(file
);
7391 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7396 fpl
->max
= SCM_MAX_FD
;
7397 fpl
->count
= nr_files
;
7398 UNIXCB(skb
).fp
= fpl
;
7399 skb
->destructor
= unix_destruct_scm
;
7400 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7401 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7403 for (i
= 0; i
< nr_files
; i
++)
7414 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7415 * causes regular reference counting to break down. We rely on the UNIX
7416 * garbage collection to take care of this problem for us.
7418 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7420 unsigned left
, total
;
7424 left
= ctx
->nr_user_files
;
7426 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7428 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7432 total
+= this_files
;
7438 while (total
< ctx
->nr_user_files
) {
7439 struct file
*file
= io_file_from_index(ctx
, total
);
7449 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7455 static int io_sqe_alloc_file_tables(struct io_rsrc_data
*file_data
,
7456 unsigned nr_tables
, unsigned nr_files
)
7460 for (i
= 0; i
< nr_tables
; i
++) {
7461 struct fixed_rsrc_table
*table
= &file_data
->table
[i
];
7462 unsigned this_files
;
7464 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7465 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
7469 nr_files
-= this_files
;
7475 for (i
= 0; i
< nr_tables
; i
++) {
7476 struct fixed_rsrc_table
*table
= &file_data
->table
[i
];
7477 kfree(table
->files
);
7482 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
7484 struct file
*file
= prsrc
->file
;
7485 #if defined(CONFIG_UNIX)
7486 struct sock
*sock
= ctx
->ring_sock
->sk
;
7487 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7488 struct sk_buff
*skb
;
7491 __skb_queue_head_init(&list
);
7494 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7495 * remove this entry and rearrange the file array.
7497 skb
= skb_dequeue(head
);
7499 struct scm_fp_list
*fp
;
7501 fp
= UNIXCB(skb
).fp
;
7502 for (i
= 0; i
< fp
->count
; i
++) {
7505 if (fp
->fp
[i
] != file
)
7508 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7509 left
= fp
->count
- 1 - i
;
7511 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7512 left
* sizeof(struct file
*));
7519 __skb_queue_tail(&list
, skb
);
7529 __skb_queue_tail(&list
, skb
);
7531 skb
= skb_dequeue(head
);
7534 if (skb_peek(&list
)) {
7535 spin_lock_irq(&head
->lock
);
7536 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7537 __skb_queue_tail(head
, skb
);
7538 spin_unlock_irq(&head
->lock
);
7545 static void __io_rsrc_put_work(struct io_rsrc_node
*ref_node
)
7547 struct io_rsrc_data
*rsrc_data
= ref_node
->rsrc_data
;
7548 struct io_ring_ctx
*ctx
= rsrc_data
->ctx
;
7549 struct io_rsrc_put
*prsrc
, *tmp
;
7551 list_for_each_entry_safe(prsrc
, tmp
, &ref_node
->rsrc_list
, list
) {
7552 list_del(&prsrc
->list
);
7553 ref_node
->rsrc_put(ctx
, prsrc
);
7557 percpu_ref_exit(&ref_node
->refs
);
7559 percpu_ref_put(&rsrc_data
->refs
);
7562 static void io_rsrc_put_work(struct work_struct
*work
)
7564 struct io_ring_ctx
*ctx
;
7565 struct llist_node
*node
;
7567 ctx
= container_of(work
, struct io_ring_ctx
, rsrc_put_work
.work
);
7568 node
= llist_del_all(&ctx
->rsrc_put_llist
);
7571 struct io_rsrc_node
*ref_node
;
7572 struct llist_node
*next
= node
->next
;
7574 ref_node
= llist_entry(node
, struct io_rsrc_node
, llist
);
7575 __io_rsrc_put_work(ref_node
);
7580 static void io_rsrc_node_ref_zero(struct percpu_ref
*ref
)
7582 struct io_rsrc_node
*node
= container_of(ref
, struct io_rsrc_node
, refs
);
7583 struct io_rsrc_data
*data
= node
->rsrc_data
;
7584 struct io_ring_ctx
*ctx
= data
->ctx
;
7585 bool first_add
= false;
7588 io_rsrc_ref_lock(ctx
);
7591 while (!list_empty(&ctx
->rsrc_ref_list
)) {
7592 node
= list_first_entry(&ctx
->rsrc_ref_list
,
7593 struct io_rsrc_node
, node
);
7594 /* recycle ref nodes in order */
7597 list_del(&node
->node
);
7598 first_add
|= llist_add(&node
->llist
, &ctx
->rsrc_put_llist
);
7600 io_rsrc_ref_unlock(ctx
);
7602 if (percpu_ref_is_dying(&data
->refs
))
7606 mod_delayed_work(system_wq
, &ctx
->rsrc_put_work
, 0);
7608 queue_delayed_work(system_wq
, &ctx
->rsrc_put_work
, delay
);
7611 static struct io_rsrc_node
*io_rsrc_node_alloc(struct io_ring_ctx
*ctx
)
7613 struct io_rsrc_node
*ref_node
;
7615 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7619 if (percpu_ref_init(&ref_node
->refs
, io_rsrc_node_ref_zero
,
7624 INIT_LIST_HEAD(&ref_node
->node
);
7625 INIT_LIST_HEAD(&ref_node
->rsrc_list
);
7626 ref_node
->done
= false;
7630 static void init_fixed_file_ref_node(struct io_ring_ctx
*ctx
,
7631 struct io_rsrc_node
*ref_node
)
7633 ref_node
->rsrc_data
= ctx
->file_data
;
7634 ref_node
->rsrc_put
= io_ring_file_put
;
7637 static void io_rsrc_node_destroy(struct io_rsrc_node
*ref_node
)
7639 percpu_ref_exit(&ref_node
->refs
);
7643 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7646 __s32 __user
*fds
= (__s32 __user
*) arg
;
7647 unsigned nr_tables
, i
;
7649 int fd
, ret
= -ENOMEM
;
7650 struct io_rsrc_node
*ref_node
;
7651 struct io_rsrc_data
*file_data
;
7657 if (nr_args
> IORING_MAX_FIXED_FILES
)
7660 file_data
= io_rsrc_data_alloc(ctx
);
7663 ctx
->file_data
= file_data
;
7665 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7666 file_data
->table
= kcalloc(nr_tables
, sizeof(*file_data
->table
),
7668 if (!file_data
->table
)
7671 if (io_sqe_alloc_file_tables(file_data
, nr_tables
, nr_args
))
7674 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7675 unsigned long file_ptr
;
7677 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7681 /* allow sparse sets */
7691 * Don't allow io_uring instances to be registered. If UNIX
7692 * isn't enabled, then this causes a reference cycle and this
7693 * instance can never get freed. If UNIX is enabled we'll
7694 * handle it just fine, but there's still no point in allowing
7695 * a ring fd as it doesn't support regular read/write anyway.
7697 if (file
->f_op
== &io_uring_fops
) {
7701 file_ptr
= (unsigned long) file
;
7702 if (__io_file_supports_async(file
, READ
))
7703 file_ptr
|= FFS_ASYNC_READ
;
7704 if (__io_file_supports_async(file
, WRITE
))
7705 file_ptr
|= FFS_ASYNC_WRITE
;
7706 if (S_ISREG(file_inode(file
)->i_mode
))
7707 file_ptr
|= FFS_ISREG
;
7708 *io_fixed_file_slot(file_data
, i
) = (struct file
*) file_ptr
;
7711 ret
= io_sqe_files_scm(ctx
);
7713 io_sqe_files_unregister(ctx
);
7717 ref_node
= io_rsrc_node_alloc(ctx
);
7719 io_sqe_files_unregister(ctx
);
7722 init_fixed_file_ref_node(ctx
, ref_node
);
7724 io_rsrc_node_set(ctx
, file_data
, ref_node
);
7727 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7728 file
= io_file_from_index(ctx
, i
);
7732 for (i
= 0; i
< nr_tables
; i
++)
7733 kfree(file_data
->table
[i
].files
);
7734 ctx
->nr_user_files
= 0;
7736 io_rsrc_data_free(ctx
->file_data
);
7737 ctx
->file_data
= NULL
;
7741 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7744 #if defined(CONFIG_UNIX)
7745 struct sock
*sock
= ctx
->ring_sock
->sk
;
7746 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7747 struct sk_buff
*skb
;
7750 * See if we can merge this file into an existing skb SCM_RIGHTS
7751 * file set. If there's no room, fall back to allocating a new skb
7752 * and filling it in.
7754 spin_lock_irq(&head
->lock
);
7755 skb
= skb_peek(head
);
7757 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7759 if (fpl
->count
< SCM_MAX_FD
) {
7760 __skb_unlink(skb
, head
);
7761 spin_unlock_irq(&head
->lock
);
7762 fpl
->fp
[fpl
->count
] = get_file(file
);
7763 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7765 spin_lock_irq(&head
->lock
);
7766 __skb_queue_head(head
, skb
);
7771 spin_unlock_irq(&head
->lock
);
7778 return __io_sqe_files_scm(ctx
, 1, index
);
7784 static int io_queue_rsrc_removal(struct io_rsrc_data
*data
, void *rsrc
)
7786 struct io_rsrc_put
*prsrc
;
7787 struct io_rsrc_node
*ref_node
= data
->node
;
7789 prsrc
= kzalloc(sizeof(*prsrc
), GFP_KERNEL
);
7794 list_add(&prsrc
->list
, &ref_node
->rsrc_list
);
7799 static inline int io_queue_file_removal(struct io_rsrc_data
*data
,
7802 return io_queue_rsrc_removal(data
, (void *)file
);
7805 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7806 struct io_uring_rsrc_update
*up
,
7809 struct io_rsrc_data
*data
= ctx
->file_data
;
7810 struct io_rsrc_node
*ref_node
;
7811 struct file
*file
, **file_slot
;
7815 bool needs_switch
= false;
7817 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7819 if (done
> ctx
->nr_user_files
)
7821 err
= io_rsrc_node_prealloc(ctx
);
7825 fds
= u64_to_user_ptr(up
->data
);
7826 for (done
= 0; done
< nr_args
; done
++) {
7828 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7832 if (fd
== IORING_REGISTER_FILES_SKIP
)
7835 i
= array_index_nospec(up
->offset
+ done
, ctx
->nr_user_files
);
7836 file_slot
= io_fixed_file_slot(ctx
->file_data
, i
);
7839 file
= (struct file
*) ((unsigned long) *file_slot
& FFS_MASK
);
7840 err
= io_queue_file_removal(data
, file
);
7844 needs_switch
= true;
7853 * Don't allow io_uring instances to be registered. If
7854 * UNIX isn't enabled, then this causes a reference
7855 * cycle and this instance can never get freed. If UNIX
7856 * is enabled we'll handle it just fine, but there's
7857 * still no point in allowing a ring fd as it doesn't
7858 * support regular read/write anyway.
7860 if (file
->f_op
== &io_uring_fops
) {
7866 err
= io_sqe_file_register(ctx
, file
, i
);
7876 percpu_ref_kill(&data
->node
->refs
);
7877 ref_node
= io_rsrc_node_get(ctx
, data
, io_ring_file_put
);
7878 io_rsrc_node_set(ctx
, data
, ref_node
);
7880 return done
? done
: err
;
7883 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7886 struct io_uring_rsrc_update up
;
7888 if (!ctx
->file_data
)
7892 if (copy_from_user(&up
, arg
, sizeof(up
)))
7897 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7900 static struct io_wq_work
*io_free_work(struct io_wq_work
*work
)
7902 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7904 req
= io_put_req_find_next(req
);
7905 return req
? &req
->work
: NULL
;
7908 static struct io_wq
*io_init_wq_offload(struct io_ring_ctx
*ctx
,
7909 struct task_struct
*task
)
7911 struct io_wq_hash
*hash
;
7912 struct io_wq_data data
;
7913 unsigned int concurrency
;
7915 hash
= ctx
->hash_map
;
7917 hash
= kzalloc(sizeof(*hash
), GFP_KERNEL
);
7919 return ERR_PTR(-ENOMEM
);
7920 refcount_set(&hash
->refs
, 1);
7921 init_waitqueue_head(&hash
->wait
);
7922 ctx
->hash_map
= hash
;
7927 data
.free_work
= io_free_work
;
7928 data
.do_work
= io_wq_submit_work
;
7930 /* Do QD, or 4 * CPUS, whatever is smallest */
7931 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7933 return io_wq_create(concurrency
, &data
);
7936 static int io_uring_alloc_task_context(struct task_struct
*task
,
7937 struct io_ring_ctx
*ctx
)
7939 struct io_uring_task
*tctx
;
7942 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
7943 if (unlikely(!tctx
))
7946 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
7947 if (unlikely(ret
)) {
7952 tctx
->io_wq
= io_init_wq_offload(ctx
, task
);
7953 if (IS_ERR(tctx
->io_wq
)) {
7954 ret
= PTR_ERR(tctx
->io_wq
);
7955 percpu_counter_destroy(&tctx
->inflight
);
7961 init_waitqueue_head(&tctx
->wait
);
7963 atomic_set(&tctx
->in_idle
, 0);
7964 task
->io_uring
= tctx
;
7965 spin_lock_init(&tctx
->task_lock
);
7966 INIT_WQ_LIST(&tctx
->task_list
);
7967 tctx
->task_state
= 0;
7968 init_task_work(&tctx
->task_work
, tctx_task_work
);
7972 void __io_uring_free(struct task_struct
*tsk
)
7974 struct io_uring_task
*tctx
= tsk
->io_uring
;
7976 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
7977 WARN_ON_ONCE(tctx
->io_wq
);
7979 percpu_counter_destroy(&tctx
->inflight
);
7981 tsk
->io_uring
= NULL
;
7984 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
7985 struct io_uring_params
*p
)
7989 /* Retain compatibility with failing for an invalid attach attempt */
7990 if ((ctx
->flags
& (IORING_SETUP_ATTACH_WQ
| IORING_SETUP_SQPOLL
)) ==
7991 IORING_SETUP_ATTACH_WQ
) {
7994 f
= fdget(p
->wq_fd
);
7997 if (f
.file
->f_op
!= &io_uring_fops
) {
8003 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8004 struct task_struct
*tsk
;
8005 struct io_sq_data
*sqd
;
8008 sqd
= io_get_sq_data(p
, &attached
);
8014 ctx
->sq_creds
= get_current_cred();
8016 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
8017 if (!ctx
->sq_thread_idle
)
8018 ctx
->sq_thread_idle
= HZ
;
8021 io_sq_thread_park(sqd
);
8022 list_add(&ctx
->sqd_list
, &sqd
->ctx_list
);
8023 io_sqd_update_thread_idle(sqd
);
8024 /* don't attach to a dying SQPOLL thread, would be racy */
8025 if (attached
&& !sqd
->thread
)
8027 io_sq_thread_unpark(sqd
);
8034 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8035 int cpu
= p
->sq_thread_cpu
;
8038 if (cpu
>= nr_cpu_ids
)
8040 if (!cpu_online(cpu
))
8048 sqd
->task_pid
= current
->pid
;
8049 sqd
->task_tgid
= current
->tgid
;
8050 tsk
= create_io_thread(io_sq_thread
, sqd
, NUMA_NO_NODE
);
8057 ret
= io_uring_alloc_task_context(tsk
, ctx
);
8058 wake_up_new_task(tsk
);
8061 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8062 /* Can't have SQ_AFF without SQPOLL */
8069 io_sq_thread_finish(ctx
);
8072 complete(&ctx
->sq_data
->exited
);
8076 static inline void __io_unaccount_mem(struct user_struct
*user
,
8077 unsigned long nr_pages
)
8079 atomic_long_sub(nr_pages
, &user
->locked_vm
);
8082 static inline int __io_account_mem(struct user_struct
*user
,
8083 unsigned long nr_pages
)
8085 unsigned long page_limit
, cur_pages
, new_pages
;
8087 /* Don't allow more pages than we can safely lock */
8088 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
8091 cur_pages
= atomic_long_read(&user
->locked_vm
);
8092 new_pages
= cur_pages
+ nr_pages
;
8093 if (new_pages
> page_limit
)
8095 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
8096 new_pages
) != cur_pages
);
8101 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8104 __io_unaccount_mem(ctx
->user
, nr_pages
);
8106 if (ctx
->mm_account
)
8107 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8110 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8115 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8120 if (ctx
->mm_account
)
8121 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8126 static void io_mem_free(void *ptr
)
8133 page
= virt_to_head_page(ptr
);
8134 if (put_page_testzero(page
))
8135 free_compound_page(page
);
8138 static void *io_mem_alloc(size_t size
)
8140 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8141 __GFP_NORETRY
| __GFP_ACCOUNT
;
8143 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8146 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8149 struct io_rings
*rings
;
8150 size_t off
, sq_array_size
;
8152 off
= struct_size(rings
, cqes
, cq_entries
);
8153 if (off
== SIZE_MAX
)
8157 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8165 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8166 if (sq_array_size
== SIZE_MAX
)
8169 if (check_add_overflow(off
, sq_array_size
, &off
))
8175 static int io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8179 if (!ctx
->user_bufs
)
8182 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8183 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8185 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
8186 unpin_user_page(imu
->bvec
[j
].bv_page
);
8188 if (imu
->acct_pages
)
8189 io_unaccount_mem(ctx
, imu
->acct_pages
);
8194 kfree(ctx
->user_bufs
);
8195 ctx
->user_bufs
= NULL
;
8196 ctx
->nr_user_bufs
= 0;
8200 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8201 void __user
*arg
, unsigned index
)
8203 struct iovec __user
*src
;
8205 #ifdef CONFIG_COMPAT
8207 struct compat_iovec __user
*ciovs
;
8208 struct compat_iovec ciov
;
8210 ciovs
= (struct compat_iovec __user
*) arg
;
8211 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8214 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8215 dst
->iov_len
= ciov
.iov_len
;
8219 src
= (struct iovec __user
*) arg
;
8220 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8226 * Not super efficient, but this is just a registration time. And we do cache
8227 * the last compound head, so generally we'll only do a full search if we don't
8230 * We check if the given compound head page has already been accounted, to
8231 * avoid double accounting it. This allows us to account the full size of the
8232 * page, not just the constituent pages of a huge page.
8234 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8235 int nr_pages
, struct page
*hpage
)
8239 /* check current page array */
8240 for (i
= 0; i
< nr_pages
; i
++) {
8241 if (!PageCompound(pages
[i
]))
8243 if (compound_head(pages
[i
]) == hpage
)
8247 /* check previously registered pages */
8248 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8249 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8251 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8252 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8254 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8262 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8263 int nr_pages
, struct io_mapped_ubuf
*imu
,
8264 struct page
**last_hpage
)
8268 for (i
= 0; i
< nr_pages
; i
++) {
8269 if (!PageCompound(pages
[i
])) {
8274 hpage
= compound_head(pages
[i
]);
8275 if (hpage
== *last_hpage
)
8277 *last_hpage
= hpage
;
8278 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8280 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8284 if (!imu
->acct_pages
)
8287 ret
= io_account_mem(ctx
, imu
->acct_pages
);
8289 imu
->acct_pages
= 0;
8293 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, struct iovec
*iov
,
8294 struct io_mapped_ubuf
*imu
,
8295 struct page
**last_hpage
)
8297 struct vm_area_struct
**vmas
= NULL
;
8298 struct page
**pages
= NULL
;
8299 unsigned long off
, start
, end
, ubuf
;
8301 int ret
, pret
, nr_pages
, i
;
8303 ubuf
= (unsigned long) iov
->iov_base
;
8304 end
= (ubuf
+ iov
->iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8305 start
= ubuf
>> PAGE_SHIFT
;
8306 nr_pages
= end
- start
;
8310 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*), GFP_KERNEL
);
8314 vmas
= kvmalloc_array(nr_pages
, sizeof(struct vm_area_struct
*),
8319 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8325 mmap_read_lock(current
->mm
);
8326 pret
= pin_user_pages(ubuf
, nr_pages
, FOLL_WRITE
| FOLL_LONGTERM
,
8328 if (pret
== nr_pages
) {
8329 /* don't support file backed memory */
8330 for (i
= 0; i
< nr_pages
; i
++) {
8331 struct vm_area_struct
*vma
= vmas
[i
];
8334 !is_file_hugepages(vma
->vm_file
)) {
8340 ret
= pret
< 0 ? pret
: -EFAULT
;
8342 mmap_read_unlock(current
->mm
);
8345 * if we did partial map, or found file backed vmas,
8346 * release any pages we did get
8349 unpin_user_pages(pages
, pret
);
8354 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, last_hpage
);
8356 unpin_user_pages(pages
, pret
);
8361 off
= ubuf
& ~PAGE_MASK
;
8362 size
= iov
->iov_len
;
8363 for (i
= 0; i
< nr_pages
; i
++) {
8366 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8367 imu
->bvec
[i
].bv_page
= pages
[i
];
8368 imu
->bvec
[i
].bv_len
= vec_len
;
8369 imu
->bvec
[i
].bv_offset
= off
;
8373 /* store original address for later verification */
8375 imu
->len
= iov
->iov_len
;
8376 imu
->nr_bvecs
= nr_pages
;
8384 static int io_buffers_map_alloc(struct io_ring_ctx
*ctx
, unsigned int nr_args
)
8388 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8391 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
8393 if (!ctx
->user_bufs
)
8399 static int io_buffer_validate(struct iovec
*iov
)
8401 unsigned long tmp
, acct_len
= iov
->iov_len
+ (PAGE_SIZE
- 1);
8404 * Don't impose further limits on the size and buffer
8405 * constraints here, we'll -EINVAL later when IO is
8406 * submitted if they are wrong.
8408 if (!iov
->iov_base
|| !iov
->iov_len
)
8411 /* arbitrary limit, but we need something */
8412 if (iov
->iov_len
> SZ_1G
)
8415 if (check_add_overflow((unsigned long)iov
->iov_base
, acct_len
, &tmp
))
8421 static int io_sqe_buffers_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8422 unsigned int nr_args
)
8426 struct page
*last_hpage
= NULL
;
8428 ret
= io_buffers_map_alloc(ctx
, nr_args
);
8432 for (i
= 0; i
< nr_args
; i
++) {
8433 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8435 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8439 ret
= io_buffer_validate(&iov
);
8443 ret
= io_sqe_buffer_register(ctx
, &iov
, imu
, &last_hpage
);
8447 ctx
->nr_user_bufs
++;
8451 io_sqe_buffers_unregister(ctx
);
8456 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8458 __s32 __user
*fds
= arg
;
8464 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8467 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8468 if (IS_ERR(ctx
->cq_ev_fd
)) {
8469 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8470 ctx
->cq_ev_fd
= NULL
;
8477 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8479 if (ctx
->cq_ev_fd
) {
8480 eventfd_ctx_put(ctx
->cq_ev_fd
);
8481 ctx
->cq_ev_fd
= NULL
;
8488 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8490 struct io_buffer
*buf
;
8491 unsigned long index
;
8493 xa_for_each(&ctx
->io_buffers
, index
, buf
)
8494 __io_remove_buffers(ctx
, buf
, index
, -1U);
8497 static void io_req_cache_free(struct list_head
*list
, struct task_struct
*tsk
)
8499 struct io_kiocb
*req
, *nxt
;
8501 list_for_each_entry_safe(req
, nxt
, list
, compl.list
) {
8502 if (tsk
&& req
->task
!= tsk
)
8504 list_del(&req
->compl.list
);
8505 kmem_cache_free(req_cachep
, req
);
8509 static void io_req_caches_free(struct io_ring_ctx
*ctx
)
8511 struct io_submit_state
*submit_state
= &ctx
->submit_state
;
8512 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
8514 mutex_lock(&ctx
->uring_lock
);
8516 if (submit_state
->free_reqs
) {
8517 kmem_cache_free_bulk(req_cachep
, submit_state
->free_reqs
,
8518 submit_state
->reqs
);
8519 submit_state
->free_reqs
= 0;
8522 io_flush_cached_locked_reqs(ctx
, cs
);
8523 io_req_cache_free(&cs
->free_list
, NULL
);
8524 mutex_unlock(&ctx
->uring_lock
);
8527 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8530 * Some may use context even when all refs and requests have been put,
8531 * and they are free to do so while still holding uring_lock or
8532 * completion_lock, see __io_req_task_submit(). Wait for them to finish.
8534 mutex_lock(&ctx
->uring_lock
);
8535 mutex_unlock(&ctx
->uring_lock
);
8536 spin_lock_irq(&ctx
->completion_lock
);
8537 spin_unlock_irq(&ctx
->completion_lock
);
8539 io_sq_thread_finish(ctx
);
8540 io_sqe_buffers_unregister(ctx
);
8542 if (ctx
->mm_account
) {
8543 mmdrop(ctx
->mm_account
);
8544 ctx
->mm_account
= NULL
;
8547 mutex_lock(&ctx
->uring_lock
);
8548 io_sqe_files_unregister(ctx
);
8549 mutex_unlock(&ctx
->uring_lock
);
8550 io_eventfd_unregister(ctx
);
8551 io_destroy_buffers(ctx
);
8553 if (ctx
->rsrc_backup_node
)
8554 io_rsrc_node_destroy(ctx
->rsrc_backup_node
);
8556 #if defined(CONFIG_UNIX)
8557 if (ctx
->ring_sock
) {
8558 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8559 sock_release(ctx
->ring_sock
);
8563 io_mem_free(ctx
->rings
);
8564 io_mem_free(ctx
->sq_sqes
);
8566 percpu_ref_exit(&ctx
->refs
);
8567 free_uid(ctx
->user
);
8568 io_req_caches_free(ctx
);
8570 io_wq_put_hash(ctx
->hash_map
);
8571 kfree(ctx
->cancel_hash
);
8575 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8577 struct io_ring_ctx
*ctx
= file
->private_data
;
8580 poll_wait(file
, &ctx
->cq_wait
, wait
);
8582 * synchronizes with barrier from wq_has_sleeper call in
8586 if (!io_sqring_full(ctx
))
8587 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8590 * Don't flush cqring overflow list here, just do a simple check.
8591 * Otherwise there could possible be ABBA deadlock:
8594 * lock(&ctx->uring_lock);
8596 * lock(&ctx->uring_lock);
8599 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
8600 * pushs them to do the flush.
8602 if (io_cqring_events(ctx
) || test_bit(0, &ctx
->cq_check_overflow
))
8603 mask
|= EPOLLIN
| EPOLLRDNORM
;
8608 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8610 struct io_ring_ctx
*ctx
= file
->private_data
;
8612 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8615 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
8617 const struct cred
*creds
;
8619 creds
= xa_erase(&ctx
->personalities
, id
);
8628 static inline bool io_run_ctx_fallback(struct io_ring_ctx
*ctx
)
8630 return io_run_task_work_head(&ctx
->exit_task_work
);
8633 struct io_tctx_exit
{
8634 struct callback_head task_work
;
8635 struct completion completion
;
8636 struct io_ring_ctx
*ctx
;
8639 static void io_tctx_exit_cb(struct callback_head
*cb
)
8641 struct io_uring_task
*tctx
= current
->io_uring
;
8642 struct io_tctx_exit
*work
;
8644 work
= container_of(cb
, struct io_tctx_exit
, task_work
);
8646 * When @in_idle, we're in cancellation and it's racy to remove the
8647 * node. It'll be removed by the end of cancellation, just ignore it.
8649 if (!atomic_read(&tctx
->in_idle
))
8650 io_uring_del_task_file((unsigned long)work
->ctx
);
8651 complete(&work
->completion
);
8654 static void io_ring_exit_work(struct work_struct
*work
)
8656 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
, exit_work
);
8657 unsigned long timeout
= jiffies
+ HZ
* 60 * 5;
8658 struct io_tctx_exit exit
;
8659 struct io_tctx_node
*node
;
8662 /* prevent SQPOLL from submitting new requests */
8664 io_sq_thread_park(ctx
->sq_data
);
8665 list_del_init(&ctx
->sqd_list
);
8666 io_sqd_update_thread_idle(ctx
->sq_data
);
8667 io_sq_thread_unpark(ctx
->sq_data
);
8671 * If we're doing polled IO and end up having requests being
8672 * submitted async (out-of-line), then completions can come in while
8673 * we're waiting for refs to drop. We need to reap these manually,
8674 * as nobody else will be looking for them.
8677 io_uring_try_cancel_requests(ctx
, NULL
, NULL
);
8679 WARN_ON_ONCE(time_after(jiffies
, timeout
));
8680 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8682 mutex_lock(&ctx
->uring_lock
);
8683 while (!list_empty(&ctx
->tctx_list
)) {
8684 WARN_ON_ONCE(time_after(jiffies
, timeout
));
8686 node
= list_first_entry(&ctx
->tctx_list
, struct io_tctx_node
,
8689 init_completion(&exit
.completion
);
8690 init_task_work(&exit
.task_work
, io_tctx_exit_cb
);
8691 ret
= task_work_add(node
->task
, &exit
.task_work
, TWA_SIGNAL
);
8692 if (WARN_ON_ONCE(ret
))
8694 wake_up_process(node
->task
);
8696 mutex_unlock(&ctx
->uring_lock
);
8697 wait_for_completion(&exit
.completion
);
8699 mutex_lock(&ctx
->uring_lock
);
8701 mutex_unlock(&ctx
->uring_lock
);
8703 io_ring_ctx_free(ctx
);
8706 /* Returns true if we found and killed one or more timeouts */
8707 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
8708 struct files_struct
*files
)
8710 struct io_kiocb
*req
, *tmp
;
8713 spin_lock_irq(&ctx
->completion_lock
);
8714 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
8715 if (io_match_task(req
, tsk
, files
)) {
8716 io_kill_timeout(req
, -ECANCELED
);
8721 io_commit_cqring(ctx
);
8722 spin_unlock_irq(&ctx
->completion_lock
);
8724 io_cqring_ev_posted(ctx
);
8725 return canceled
!= 0;
8728 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8730 unsigned long index
;
8731 struct creds
*creds
;
8733 mutex_lock(&ctx
->uring_lock
);
8734 percpu_ref_kill(&ctx
->refs
);
8735 /* if force is set, the ring is going away. always drop after that */
8736 ctx
->cq_overflow_flushed
= 1;
8738 __io_cqring_overflow_flush(ctx
, true);
8739 xa_for_each(&ctx
->personalities
, index
, creds
)
8740 io_unregister_personality(ctx
, index
);
8741 mutex_unlock(&ctx
->uring_lock
);
8743 io_kill_timeouts(ctx
, NULL
, NULL
);
8744 io_poll_remove_all(ctx
, NULL
, NULL
);
8746 /* if we failed setting up the ctx, we might not have any rings */
8747 io_iopoll_try_reap_events(ctx
);
8749 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8751 * Use system_unbound_wq to avoid spawning tons of event kworkers
8752 * if we're exiting a ton of rings at the same time. It just adds
8753 * noise and overhead, there's no discernable change in runtime
8754 * over using system_wq.
8756 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8759 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8761 struct io_ring_ctx
*ctx
= file
->private_data
;
8763 file
->private_data
= NULL
;
8764 io_ring_ctx_wait_and_kill(ctx
);
8768 struct io_task_cancel
{
8769 struct task_struct
*task
;
8770 struct files_struct
*files
;
8773 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8775 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8776 struct io_task_cancel
*cancel
= data
;
8779 if (cancel
->files
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
8780 unsigned long flags
;
8781 struct io_ring_ctx
*ctx
= req
->ctx
;
8783 /* protect against races with linked timeouts */
8784 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
8785 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8786 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
8788 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8793 static bool io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8794 struct task_struct
*task
,
8795 struct files_struct
*files
)
8797 struct io_defer_entry
*de
;
8800 spin_lock_irq(&ctx
->completion_lock
);
8801 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8802 if (io_match_task(de
->req
, task
, files
)) {
8803 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8807 spin_unlock_irq(&ctx
->completion_lock
);
8808 if (list_empty(&list
))
8811 while (!list_empty(&list
)) {
8812 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8813 list_del_init(&de
->list
);
8814 io_req_complete_failed(de
->req
, -ECANCELED
);
8820 static bool io_cancel_ctx_cb(struct io_wq_work
*work
, void *data
)
8822 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8824 return req
->ctx
== data
;
8827 static bool io_uring_try_cancel_iowq(struct io_ring_ctx
*ctx
)
8829 struct io_tctx_node
*node
;
8830 enum io_wq_cancel cret
;
8833 mutex_lock(&ctx
->uring_lock
);
8834 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
8835 struct io_uring_task
*tctx
= node
->task
->io_uring
;
8838 * io_wq will stay alive while we hold uring_lock, because it's
8839 * killed after ctx nodes, which requires to take the lock.
8841 if (!tctx
|| !tctx
->io_wq
)
8843 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_ctx_cb
, ctx
, true);
8844 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
8846 mutex_unlock(&ctx
->uring_lock
);
8851 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
8852 struct task_struct
*task
,
8853 struct files_struct
*files
)
8855 struct io_task_cancel cancel
= { .task
= task
, .files
= files
, };
8856 struct io_uring_task
*tctx
= task
? task
->io_uring
: NULL
;
8859 enum io_wq_cancel cret
;
8863 ret
|= io_uring_try_cancel_iowq(ctx
);
8864 } else if (tctx
&& tctx
->io_wq
) {
8866 * Cancels requests of all rings, not only @ctx, but
8867 * it's fine as the task is in exit/exec.
8869 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_task_cb
,
8871 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
8874 /* SQPOLL thread does its own polling */
8875 if ((!(ctx
->flags
& IORING_SETUP_SQPOLL
) && !files
) ||
8876 (ctx
->sq_data
&& ctx
->sq_data
->thread
== current
)) {
8877 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8878 io_iopoll_try_reap_events(ctx
);
8883 ret
|= io_cancel_defer_files(ctx
, task
, files
);
8884 ret
|= io_poll_remove_all(ctx
, task
, files
);
8885 ret
|= io_kill_timeouts(ctx
, task
, files
);
8886 ret
|= io_run_task_work();
8887 ret
|= io_run_ctx_fallback(ctx
);
8894 static int io_uring_count_inflight(struct io_ring_ctx
*ctx
,
8895 struct task_struct
*task
,
8896 struct files_struct
*files
)
8898 struct io_kiocb
*req
;
8901 spin_lock_irq(&ctx
->inflight_lock
);
8902 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
)
8903 cnt
+= io_match_task(req
, task
, files
);
8904 spin_unlock_irq(&ctx
->inflight_lock
);
8908 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8909 struct task_struct
*task
,
8910 struct files_struct
*files
)
8912 while (!list_empty_careful(&ctx
->inflight_list
)) {
8916 inflight
= io_uring_count_inflight(ctx
, task
, files
);
8920 io_uring_try_cancel_requests(ctx
, task
, files
);
8922 prepare_to_wait(&task
->io_uring
->wait
, &wait
,
8923 TASK_UNINTERRUPTIBLE
);
8924 if (inflight
== io_uring_count_inflight(ctx
, task
, files
))
8926 finish_wait(&task
->io_uring
->wait
, &wait
);
8930 static int __io_uring_add_task_file(struct io_ring_ctx
*ctx
)
8932 struct io_uring_task
*tctx
= current
->io_uring
;
8933 struct io_tctx_node
*node
;
8936 if (unlikely(!tctx
)) {
8937 ret
= io_uring_alloc_task_context(current
, ctx
);
8940 tctx
= current
->io_uring
;
8942 if (!xa_load(&tctx
->xa
, (unsigned long)ctx
)) {
8943 node
= kmalloc(sizeof(*node
), GFP_KERNEL
);
8947 node
->task
= current
;
8949 ret
= xa_err(xa_store(&tctx
->xa
, (unsigned long)ctx
,
8956 mutex_lock(&ctx
->uring_lock
);
8957 list_add(&node
->ctx_node
, &ctx
->tctx_list
);
8958 mutex_unlock(&ctx
->uring_lock
);
8965 * Note that this task has used io_uring. We use it for cancelation purposes.
8967 static inline int io_uring_add_task_file(struct io_ring_ctx
*ctx
)
8969 struct io_uring_task
*tctx
= current
->io_uring
;
8971 if (likely(tctx
&& tctx
->last
== ctx
))
8973 return __io_uring_add_task_file(ctx
);
8977 * Remove this io_uring_file -> task mapping.
8979 static void io_uring_del_task_file(unsigned long index
)
8981 struct io_uring_task
*tctx
= current
->io_uring
;
8982 struct io_tctx_node
*node
;
8986 node
= xa_erase(&tctx
->xa
, index
);
8990 WARN_ON_ONCE(current
!= node
->task
);
8991 WARN_ON_ONCE(list_empty(&node
->ctx_node
));
8993 mutex_lock(&node
->ctx
->uring_lock
);
8994 list_del(&node
->ctx_node
);
8995 mutex_unlock(&node
->ctx
->uring_lock
);
8997 if (tctx
->last
== node
->ctx
)
9002 static void io_uring_clean_tctx(struct io_uring_task
*tctx
)
9004 struct io_tctx_node
*node
;
9005 unsigned long index
;
9007 xa_for_each(&tctx
->xa
, index
, node
)
9008 io_uring_del_task_file(index
);
9010 io_wq_put_and_exit(tctx
->io_wq
);
9015 static s64
tctx_inflight(struct io_uring_task
*tctx
)
9017 return percpu_counter_sum(&tctx
->inflight
);
9020 static void io_sqpoll_cancel_cb(struct callback_head
*cb
)
9022 struct io_tctx_exit
*work
= container_of(cb
, struct io_tctx_exit
, task_work
);
9023 struct io_ring_ctx
*ctx
= work
->ctx
;
9024 struct io_sq_data
*sqd
= ctx
->sq_data
;
9027 io_uring_cancel_sqpoll(ctx
);
9028 complete(&work
->completion
);
9031 static void io_sqpoll_cancel_sync(struct io_ring_ctx
*ctx
)
9033 struct io_sq_data
*sqd
= ctx
->sq_data
;
9034 struct io_tctx_exit work
= { .ctx
= ctx
, };
9035 struct task_struct
*task
;
9037 io_sq_thread_park(sqd
);
9038 list_del_init(&ctx
->sqd_list
);
9039 io_sqd_update_thread_idle(sqd
);
9042 init_completion(&work
.completion
);
9043 init_task_work(&work
.task_work
, io_sqpoll_cancel_cb
);
9044 io_task_work_add_head(&sqd
->park_task_work
, &work
.task_work
);
9045 wake_up_process(task
);
9047 io_sq_thread_unpark(sqd
);
9050 wait_for_completion(&work
.completion
);
9053 void __io_uring_files_cancel(struct files_struct
*files
)
9055 struct io_uring_task
*tctx
= current
->io_uring
;
9056 struct io_tctx_node
*node
;
9057 unsigned long index
;
9059 /* make sure overflow events are dropped */
9060 atomic_inc(&tctx
->in_idle
);
9061 xa_for_each(&tctx
->xa
, index
, node
) {
9062 struct io_ring_ctx
*ctx
= node
->ctx
;
9065 io_sqpoll_cancel_sync(ctx
);
9068 io_uring_cancel_files(ctx
, current
, files
);
9070 io_uring_try_cancel_requests(ctx
, current
, NULL
);
9072 atomic_dec(&tctx
->in_idle
);
9075 io_uring_clean_tctx(tctx
);
9078 /* should only be called by SQPOLL task */
9079 static void io_uring_cancel_sqpoll(struct io_ring_ctx
*ctx
)
9081 struct io_sq_data
*sqd
= ctx
->sq_data
;
9082 struct io_uring_task
*tctx
= current
->io_uring
;
9086 WARN_ON_ONCE(!sqd
|| ctx
->sq_data
->thread
!= current
);
9088 atomic_inc(&tctx
->in_idle
);
9090 /* read completions before cancelations */
9091 inflight
= tctx_inflight(tctx
);
9094 io_uring_try_cancel_requests(ctx
, current
, NULL
);
9096 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
9098 * If we've seen completions, retry without waiting. This
9099 * avoids a race where a completion comes in before we did
9100 * prepare_to_wait().
9102 if (inflight
== tctx_inflight(tctx
))
9104 finish_wait(&tctx
->wait
, &wait
);
9106 atomic_dec(&tctx
->in_idle
);
9110 * Find any io_uring fd that this task has registered or done IO on, and cancel
9113 void __io_uring_task_cancel(void)
9115 struct io_uring_task
*tctx
= current
->io_uring
;
9119 /* make sure overflow events are dropped */
9120 atomic_inc(&tctx
->in_idle
);
9121 __io_uring_files_cancel(NULL
);
9124 /* read completions before cancelations */
9125 inflight
= tctx_inflight(tctx
);
9128 __io_uring_files_cancel(NULL
);
9130 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
9133 * If we've seen completions, retry without waiting. This
9134 * avoids a race where a completion comes in before we did
9135 * prepare_to_wait().
9137 if (inflight
== tctx_inflight(tctx
))
9139 finish_wait(&tctx
->wait
, &wait
);
9142 atomic_dec(&tctx
->in_idle
);
9144 io_uring_clean_tctx(tctx
);
9145 /* all current's requests should be gone, we can kill tctx */
9146 __io_uring_free(current
);
9149 static void *io_uring_validate_mmap_request(struct file
*file
,
9150 loff_t pgoff
, size_t sz
)
9152 struct io_ring_ctx
*ctx
= file
->private_data
;
9153 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9158 case IORING_OFF_SQ_RING
:
9159 case IORING_OFF_CQ_RING
:
9162 case IORING_OFF_SQES
:
9166 return ERR_PTR(-EINVAL
);
9169 page
= virt_to_head_page(ptr
);
9170 if (sz
> page_size(page
))
9171 return ERR_PTR(-EINVAL
);
9178 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9180 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9184 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9186 return PTR_ERR(ptr
);
9188 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9189 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9192 #else /* !CONFIG_MMU */
9194 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9196 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9199 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9201 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9204 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9205 unsigned long addr
, unsigned long len
,
9206 unsigned long pgoff
, unsigned long flags
)
9210 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9212 return PTR_ERR(ptr
);
9214 return (unsigned long) ptr
;
9217 #endif /* !CONFIG_MMU */
9219 static int io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9224 if (!io_sqring_full(ctx
))
9226 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9228 if (!io_sqring_full(ctx
))
9231 } while (!signal_pending(current
));
9233 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9237 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9238 struct __kernel_timespec __user
**ts
,
9239 const sigset_t __user
**sig
)
9241 struct io_uring_getevents_arg arg
;
9244 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9245 * is just a pointer to the sigset_t.
9247 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9248 *sig
= (const sigset_t __user
*) argp
;
9254 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9255 * timespec and sigset_t pointers if good.
9257 if (*argsz
!= sizeof(arg
))
9259 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9261 *sig
= u64_to_user_ptr(arg
.sigmask
);
9262 *argsz
= arg
.sigmask_sz
;
9263 *ts
= u64_to_user_ptr(arg
.ts
);
9267 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9268 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9271 struct io_ring_ctx
*ctx
;
9278 if (unlikely(flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9279 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
)))
9283 if (unlikely(!f
.file
))
9287 if (unlikely(f
.file
->f_op
!= &io_uring_fops
))
9291 ctx
= f
.file
->private_data
;
9292 if (unlikely(!percpu_ref_tryget(&ctx
->refs
)))
9296 if (unlikely(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9300 * For SQ polling, the thread will do all submissions and completions.
9301 * Just return the requested submit count, and wake the thread if
9305 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9306 io_cqring_overflow_flush(ctx
, false);
9309 if (unlikely(ctx
->sq_data
->thread
== NULL
)) {
9312 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9313 wake_up(&ctx
->sq_data
->wait
);
9314 if (flags
& IORING_ENTER_SQ_WAIT
) {
9315 ret
= io_sqpoll_wait_sq(ctx
);
9319 submitted
= to_submit
;
9320 } else if (to_submit
) {
9321 ret
= io_uring_add_task_file(ctx
);
9324 mutex_lock(&ctx
->uring_lock
);
9325 submitted
= io_submit_sqes(ctx
, to_submit
);
9326 mutex_unlock(&ctx
->uring_lock
);
9328 if (submitted
!= to_submit
)
9331 if (flags
& IORING_ENTER_GETEVENTS
) {
9332 const sigset_t __user
*sig
;
9333 struct __kernel_timespec __user
*ts
;
9335 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
9339 min_complete
= min(min_complete
, ctx
->cq_entries
);
9342 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9343 * space applications don't need to do io completion events
9344 * polling again, they can rely on io_sq_thread to do polling
9345 * work, which can reduce cpu usage and uring_lock contention.
9347 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
9348 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9349 ret
= io_iopoll_check(ctx
, min_complete
);
9351 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
9356 percpu_ref_put(&ctx
->refs
);
9359 return submitted
? submitted
: ret
;
9362 #ifdef CONFIG_PROC_FS
9363 static int io_uring_show_cred(struct seq_file
*m
, unsigned int id
,
9364 const struct cred
*cred
)
9366 struct user_namespace
*uns
= seq_user_ns(m
);
9367 struct group_info
*gi
;
9372 seq_printf(m
, "%5d\n", id
);
9373 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
9374 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
9375 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
9376 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
9377 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
9378 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
9379 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
9380 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
9381 seq_puts(m
, "\n\tGroups:\t");
9382 gi
= cred
->group_info
;
9383 for (g
= 0; g
< gi
->ngroups
; g
++) {
9384 seq_put_decimal_ull(m
, g
? " " : "",
9385 from_kgid_munged(uns
, gi
->gid
[g
]));
9387 seq_puts(m
, "\n\tCapEff:\t");
9388 cap
= cred
->cap_effective
;
9389 CAP_FOR_EACH_U32(__capi
)
9390 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
9395 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
9397 struct io_sq_data
*sq
= NULL
;
9402 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9403 * since fdinfo case grabs it in the opposite direction of normal use
9404 * cases. If we fail to get the lock, we just don't iterate any
9405 * structures that could be going away outside the io_uring mutex.
9407 has_lock
= mutex_trylock(&ctx
->uring_lock
);
9409 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9415 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
9416 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
9417 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
9418 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
9419 struct file
*f
= io_file_from_index(ctx
, i
);
9422 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
9424 seq_printf(m
, "%5u: <none>\n", i
);
9426 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
9427 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
9428 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
9430 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
9431 (unsigned int) buf
->len
);
9433 if (has_lock
&& !xa_empty(&ctx
->personalities
)) {
9434 unsigned long index
;
9435 const struct cred
*cred
;
9437 seq_printf(m
, "Personalities:\n");
9438 xa_for_each(&ctx
->personalities
, index
, cred
)
9439 io_uring_show_cred(m
, index
, cred
);
9441 seq_printf(m
, "PollList:\n");
9442 spin_lock_irq(&ctx
->completion_lock
);
9443 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9444 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9445 struct io_kiocb
*req
;
9447 hlist_for_each_entry(req
, list
, hash_node
)
9448 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9449 req
->task
->task_works
!= NULL
);
9451 spin_unlock_irq(&ctx
->completion_lock
);
9453 mutex_unlock(&ctx
->uring_lock
);
9456 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9458 struct io_ring_ctx
*ctx
= f
->private_data
;
9460 if (percpu_ref_tryget(&ctx
->refs
)) {
9461 __io_uring_show_fdinfo(ctx
, m
);
9462 percpu_ref_put(&ctx
->refs
);
9467 static const struct file_operations io_uring_fops
= {
9468 .release
= io_uring_release
,
9469 .mmap
= io_uring_mmap
,
9471 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9472 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9474 .poll
= io_uring_poll
,
9475 .fasync
= io_uring_fasync
,
9476 #ifdef CONFIG_PROC_FS
9477 .show_fdinfo
= io_uring_show_fdinfo
,
9481 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9482 struct io_uring_params
*p
)
9484 struct io_rings
*rings
;
9485 size_t size
, sq_array_offset
;
9487 /* make sure these are sane, as we already accounted them */
9488 ctx
->sq_entries
= p
->sq_entries
;
9489 ctx
->cq_entries
= p
->cq_entries
;
9491 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9492 if (size
== SIZE_MAX
)
9495 rings
= io_mem_alloc(size
);
9500 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9501 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9502 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9503 rings
->sq_ring_entries
= p
->sq_entries
;
9504 rings
->cq_ring_entries
= p
->cq_entries
;
9505 ctx
->sq_mask
= rings
->sq_ring_mask
;
9506 ctx
->cq_mask
= rings
->cq_ring_mask
;
9508 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9509 if (size
== SIZE_MAX
) {
9510 io_mem_free(ctx
->rings
);
9515 ctx
->sq_sqes
= io_mem_alloc(size
);
9516 if (!ctx
->sq_sqes
) {
9517 io_mem_free(ctx
->rings
);
9525 static int io_uring_install_fd(struct io_ring_ctx
*ctx
, struct file
*file
)
9529 fd
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9533 ret
= io_uring_add_task_file(ctx
);
9538 fd_install(fd
, file
);
9543 * Allocate an anonymous fd, this is what constitutes the application
9544 * visible backing of an io_uring instance. The application mmaps this
9545 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9546 * we have to tie this fd to a socket for file garbage collection purposes.
9548 static struct file
*io_uring_get_file(struct io_ring_ctx
*ctx
)
9551 #if defined(CONFIG_UNIX)
9554 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9557 return ERR_PTR(ret
);
9560 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9561 O_RDWR
| O_CLOEXEC
);
9562 #if defined(CONFIG_UNIX)
9564 sock_release(ctx
->ring_sock
);
9565 ctx
->ring_sock
= NULL
;
9567 ctx
->ring_sock
->file
= file
;
9573 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9574 struct io_uring_params __user
*params
)
9576 struct io_ring_ctx
*ctx
;
9582 if (entries
> IORING_MAX_ENTRIES
) {
9583 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9585 entries
= IORING_MAX_ENTRIES
;
9589 * Use twice as many entries for the CQ ring. It's possible for the
9590 * application to drive a higher depth than the size of the SQ ring,
9591 * since the sqes are only used at submission time. This allows for
9592 * some flexibility in overcommitting a bit. If the application has
9593 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9594 * of CQ ring entries manually.
9596 p
->sq_entries
= roundup_pow_of_two(entries
);
9597 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9599 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9600 * to a power-of-two, if it isn't already. We do NOT impose
9601 * any cq vs sq ring sizing.
9605 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9606 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9608 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9610 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9611 if (p
->cq_entries
< p
->sq_entries
)
9614 p
->cq_entries
= 2 * p
->sq_entries
;
9617 ctx
= io_ring_ctx_alloc(p
);
9620 ctx
->compat
= in_compat_syscall();
9621 if (!capable(CAP_IPC_LOCK
))
9622 ctx
->user
= get_uid(current_user());
9625 * This is just grabbed for accounting purposes. When a process exits,
9626 * the mm is exited and dropped before the files, hence we need to hang
9627 * on to this mm purely for the purposes of being able to unaccount
9628 * memory (locked/pinned vm). It's not used for anything else.
9630 mmgrab(current
->mm
);
9631 ctx
->mm_account
= current
->mm
;
9633 ret
= io_allocate_scq_urings(ctx
, p
);
9637 ret
= io_sq_offload_create(ctx
, p
);
9641 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9642 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9643 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9644 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9645 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9646 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9647 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9648 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9650 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9651 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9652 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9653 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9654 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9655 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9656 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9657 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9659 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9660 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9661 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9662 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
9663 IORING_FEAT_EXT_ARG
| IORING_FEAT_NATIVE_WORKERS
;
9665 if (copy_to_user(params
, p
, sizeof(*p
))) {
9670 file
= io_uring_get_file(ctx
);
9672 ret
= PTR_ERR(file
);
9677 * Install ring fd as the very last thing, so we don't risk someone
9678 * having closed it before we finish setup
9680 ret
= io_uring_install_fd(ctx
, file
);
9682 /* fput will clean it up */
9687 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9690 io_ring_ctx_wait_and_kill(ctx
);
9695 * Sets up an aio uring context, and returns the fd. Applications asks for a
9696 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9697 * params structure passed in.
9699 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9701 struct io_uring_params p
;
9704 if (copy_from_user(&p
, params
, sizeof(p
)))
9706 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9711 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9712 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9713 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9714 IORING_SETUP_R_DISABLED
))
9717 return io_uring_create(entries
, &p
, params
);
9720 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9721 struct io_uring_params __user
*, params
)
9723 return io_uring_setup(entries
, params
);
9726 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9728 struct io_uring_probe
*p
;
9732 size
= struct_size(p
, ops
, nr_args
);
9733 if (size
== SIZE_MAX
)
9735 p
= kzalloc(size
, GFP_KERNEL
);
9740 if (copy_from_user(p
, arg
, size
))
9743 if (memchr_inv(p
, 0, size
))
9746 p
->last_op
= IORING_OP_LAST
- 1;
9747 if (nr_args
> IORING_OP_LAST
)
9748 nr_args
= IORING_OP_LAST
;
9750 for (i
= 0; i
< nr_args
; i
++) {
9752 if (!io_op_defs
[i
].not_supported
)
9753 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9758 if (copy_to_user(arg
, p
, size
))
9765 static int io_register_personality(struct io_ring_ctx
*ctx
)
9767 const struct cred
*creds
;
9771 creds
= get_current_cred();
9773 ret
= xa_alloc_cyclic(&ctx
->personalities
, &id
, (void *)creds
,
9774 XA_LIMIT(0, USHRT_MAX
), &ctx
->pers_next
, GFP_KERNEL
);
9781 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9782 unsigned int nr_args
)
9784 struct io_uring_restriction
*res
;
9788 /* Restrictions allowed only if rings started disabled */
9789 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9792 /* We allow only a single restrictions registration */
9793 if (ctx
->restrictions
.registered
)
9796 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9799 size
= array_size(nr_args
, sizeof(*res
));
9800 if (size
== SIZE_MAX
)
9803 res
= memdup_user(arg
, size
);
9805 return PTR_ERR(res
);
9809 for (i
= 0; i
< nr_args
; i
++) {
9810 switch (res
[i
].opcode
) {
9811 case IORING_RESTRICTION_REGISTER_OP
:
9812 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9817 __set_bit(res
[i
].register_op
,
9818 ctx
->restrictions
.register_op
);
9820 case IORING_RESTRICTION_SQE_OP
:
9821 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9826 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9828 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9829 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9831 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9832 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9841 /* Reset all restrictions if an error happened */
9843 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9845 ctx
->restrictions
.registered
= true;
9851 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9853 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9856 if (ctx
->restrictions
.registered
)
9857 ctx
->restricted
= 1;
9859 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9860 if (ctx
->sq_data
&& wq_has_sleeper(&ctx
->sq_data
->wait
))
9861 wake_up(&ctx
->sq_data
->wait
);
9865 static bool io_register_op_must_quiesce(int op
)
9868 case IORING_UNREGISTER_FILES
:
9869 case IORING_REGISTER_FILES_UPDATE
:
9870 case IORING_REGISTER_PROBE
:
9871 case IORING_REGISTER_PERSONALITY
:
9872 case IORING_UNREGISTER_PERSONALITY
:
9879 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
9880 void __user
*arg
, unsigned nr_args
)
9881 __releases(ctx
->uring_lock
)
9882 __acquires(ctx
->uring_lock
)
9887 * We're inside the ring mutex, if the ref is already dying, then
9888 * someone else killed the ctx or is already going through
9889 * io_uring_register().
9891 if (percpu_ref_is_dying(&ctx
->refs
))
9894 if (io_register_op_must_quiesce(opcode
)) {
9895 percpu_ref_kill(&ctx
->refs
);
9898 * Drop uring mutex before waiting for references to exit. If
9899 * another thread is currently inside io_uring_enter() it might
9900 * need to grab the uring_lock to make progress. If we hold it
9901 * here across the drain wait, then we can deadlock. It's safe
9902 * to drop the mutex here, since no new references will come in
9903 * after we've killed the percpu ref.
9905 mutex_unlock(&ctx
->uring_lock
);
9907 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
9910 ret
= io_run_task_work_sig();
9915 mutex_lock(&ctx
->uring_lock
);
9918 percpu_ref_resurrect(&ctx
->refs
);
9923 if (ctx
->restricted
) {
9924 if (opcode
>= IORING_REGISTER_LAST
) {
9929 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
9936 case IORING_REGISTER_BUFFERS
:
9937 ret
= io_sqe_buffers_register(ctx
, arg
, nr_args
);
9939 case IORING_UNREGISTER_BUFFERS
:
9943 ret
= io_sqe_buffers_unregister(ctx
);
9945 case IORING_REGISTER_FILES
:
9946 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
9948 case IORING_UNREGISTER_FILES
:
9952 ret
= io_sqe_files_unregister(ctx
);
9954 case IORING_REGISTER_FILES_UPDATE
:
9955 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
9957 case IORING_REGISTER_EVENTFD
:
9958 case IORING_REGISTER_EVENTFD_ASYNC
:
9962 ret
= io_eventfd_register(ctx
, arg
);
9965 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
9966 ctx
->eventfd_async
= 1;
9968 ctx
->eventfd_async
= 0;
9970 case IORING_UNREGISTER_EVENTFD
:
9974 ret
= io_eventfd_unregister(ctx
);
9976 case IORING_REGISTER_PROBE
:
9978 if (!arg
|| nr_args
> 256)
9980 ret
= io_probe(ctx
, arg
, nr_args
);
9982 case IORING_REGISTER_PERSONALITY
:
9986 ret
= io_register_personality(ctx
);
9988 case IORING_UNREGISTER_PERSONALITY
:
9992 ret
= io_unregister_personality(ctx
, nr_args
);
9994 case IORING_REGISTER_ENABLE_RINGS
:
9998 ret
= io_register_enable_rings(ctx
);
10000 case IORING_REGISTER_RESTRICTIONS
:
10001 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
10009 if (io_register_op_must_quiesce(opcode
)) {
10010 /* bring the ctx back to life */
10011 percpu_ref_reinit(&ctx
->refs
);
10013 reinit_completion(&ctx
->ref_comp
);
10018 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
10019 void __user
*, arg
, unsigned int, nr_args
)
10021 struct io_ring_ctx
*ctx
;
10030 if (f
.file
->f_op
!= &io_uring_fops
)
10033 ctx
= f
.file
->private_data
;
10035 io_run_task_work();
10037 mutex_lock(&ctx
->uring_lock
);
10038 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
10039 mutex_unlock(&ctx
->uring_lock
);
10040 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
10041 ctx
->cq_ev_fd
!= NULL
, ret
);
10047 static int __init
io_uring_init(void)
10049 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10050 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10051 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10054 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10055 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10056 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
10057 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
10058 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
10059 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
10060 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
10061 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
10062 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
10063 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
10064 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
10065 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
10066 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
10067 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
10068 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
10069 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
10070 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
10071 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
10072 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
10073 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
10074 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
10075 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
10076 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
10077 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
10078 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
10079 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
10080 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
10081 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
10082 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
10083 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
10084 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
10086 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
10087 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
10088 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
|
10092 __initcall(io_uring_init
);