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/kthread.h>
61 #include <linux/blkdev.h>
62 #include <linux/bvec.h>
63 #include <linux/net.h>
65 #include <net/af_unix.h>
67 #include <linux/anon_inodes.h>
68 #include <linux/sched/mm.h>
69 #include <linux/uaccess.h>
70 #include <linux/nospec.h>
71 #include <linux/sizes.h>
72 #include <linux/hugetlb.h>
73 #include <linux/highmem.h>
74 #include <linux/namei.h>
75 #include <linux/fsnotify.h>
76 #include <linux/fadvise.h>
77 #include <linux/eventpoll.h>
78 #include <linux/fs_struct.h>
79 #include <linux/splice.h>
80 #include <linux/task_work.h>
81 #include <linux/pagemap.h>
82 #include <linux/io_uring.h>
83 #include <linux/blk-cgroup.h>
84 #include <linux/audit.h>
86 #define CREATE_TRACE_POINTS
87 #include <trace/events/io_uring.h>
89 #include <uapi/linux/io_uring.h>
94 #define IORING_MAX_ENTRIES 32768
95 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
98 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
100 #define IORING_FILE_TABLE_SHIFT 9
101 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
102 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
103 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
104 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
105 IORING_REGISTER_LAST + IORING_OP_LAST)
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 struct io_mapped_ubuf
{
193 struct bio_vec
*bvec
;
194 unsigned int nr_bvecs
;
195 unsigned long acct_pages
;
198 struct fixed_file_table
{
202 struct fixed_file_ref_node
{
203 struct percpu_ref refs
;
204 struct list_head node
;
205 struct list_head file_list
;
206 struct fixed_file_data
*file_data
;
207 struct llist_node llist
;
211 struct fixed_file_data
{
212 struct fixed_file_table
*table
;
213 struct io_ring_ctx
*ctx
;
215 struct fixed_file_ref_node
*node
;
216 struct percpu_ref refs
;
217 struct completion done
;
218 struct list_head ref_list
;
223 struct list_head list
;
229 struct io_restriction
{
230 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
231 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
232 u8 sqe_flags_allowed
;
233 u8 sqe_flags_required
;
241 /* ctx's that are using this sqd */
242 struct list_head ctx_list
;
243 struct list_head ctx_new_list
;
244 struct mutex ctx_lock
;
246 struct task_struct
*thread
;
247 struct wait_queue_head wait
;
249 unsigned sq_thread_idle
;
254 struct percpu_ref refs
;
255 } ____cacheline_aligned_in_smp
;
259 unsigned int compat
: 1;
260 unsigned int limit_mem
: 1;
261 unsigned int cq_overflow_flushed
: 1;
262 unsigned int drain_next
: 1;
263 unsigned int eventfd_async
: 1;
264 unsigned int restricted
: 1;
267 * Ring buffer of indices into array of io_uring_sqe, which is
268 * mmapped by the application using the IORING_OFF_SQES offset.
270 * This indirection could e.g. be used to assign fixed
271 * io_uring_sqe entries to operations and only submit them to
272 * the queue when needed.
274 * The kernel modifies neither the indices array nor the entries
278 unsigned cached_sq_head
;
281 unsigned sq_thread_idle
;
282 unsigned cached_sq_dropped
;
283 unsigned cached_cq_overflow
;
284 unsigned long sq_check_overflow
;
286 struct list_head defer_list
;
287 struct list_head timeout_list
;
288 struct list_head cq_overflow_list
;
290 struct io_uring_sqe
*sq_sqes
;
291 } ____cacheline_aligned_in_smp
;
293 struct io_rings
*rings
;
299 * For SQPOLL usage - we hold a reference to the parent task, so we
300 * have access to the ->files
302 struct task_struct
*sqo_task
;
304 /* Only used for accounting purposes */
305 struct mm_struct
*mm_account
;
307 #ifdef CONFIG_BLK_CGROUP
308 struct cgroup_subsys_state
*sqo_blkcg_css
;
311 struct io_sq_data
*sq_data
; /* if using sq thread polling */
313 struct wait_queue_head sqo_sq_wait
;
314 struct list_head sqd_list
;
317 * If used, fixed file set. Writers must ensure that ->refs is dead,
318 * readers must ensure that ->refs is alive as long as the file* is
319 * used. Only updated through io_uring_register(2).
321 struct fixed_file_data
*file_data
;
322 unsigned nr_user_files
;
324 /* if used, fixed mapped user buffers */
325 unsigned nr_user_bufs
;
326 struct io_mapped_ubuf
*user_bufs
;
328 struct user_struct
*user
;
330 const struct cred
*creds
;
334 unsigned int sessionid
;
337 struct completion ref_comp
;
338 struct completion sq_thread_comp
;
340 /* if all else fails... */
341 struct io_kiocb
*fallback_req
;
343 #if defined(CONFIG_UNIX)
344 struct socket
*ring_sock
;
347 struct idr io_buffer_idr
;
349 struct idr personality_idr
;
352 unsigned cached_cq_tail
;
355 atomic_t cq_timeouts
;
356 unsigned long cq_check_overflow
;
357 struct wait_queue_head cq_wait
;
358 struct fasync_struct
*cq_fasync
;
359 struct eventfd_ctx
*cq_ev_fd
;
360 } ____cacheline_aligned_in_smp
;
363 struct mutex uring_lock
;
364 wait_queue_head_t wait
;
365 } ____cacheline_aligned_in_smp
;
368 spinlock_t completion_lock
;
371 * ->iopoll_list is protected by the ctx->uring_lock for
372 * io_uring instances that don't use IORING_SETUP_SQPOLL.
373 * For SQPOLL, only the single threaded io_sq_thread() will
374 * manipulate the list, hence no extra locking is needed there.
376 struct list_head iopoll_list
;
377 struct hlist_head
*cancel_hash
;
378 unsigned cancel_hash_bits
;
379 bool poll_multi_file
;
381 spinlock_t inflight_lock
;
382 struct list_head inflight_list
;
383 } ____cacheline_aligned_in_smp
;
385 struct delayed_work file_put_work
;
386 struct llist_head file_put_llist
;
388 struct work_struct exit_work
;
389 struct io_restriction restrictions
;
393 * First field must be the file pointer in all the
394 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
396 struct io_poll_iocb
{
398 struct wait_queue_head
*head
;
402 struct wait_queue_entry wait
;
405 struct io_poll_remove
{
412 struct file
*put_file
;
416 struct io_timeout_data
{
417 struct io_kiocb
*req
;
418 struct hrtimer timer
;
419 struct timespec64 ts
;
420 enum hrtimer_mode mode
;
425 struct sockaddr __user
*addr
;
426 int __user
*addr_len
;
428 unsigned long nofile
;
448 struct list_head list
;
449 /* head of the link, used by linked timeouts only */
450 struct io_kiocb
*head
;
453 struct io_timeout_rem
{
458 struct timespec64 ts
;
463 /* NOTE: kiocb has the file as the first member, so don't do it here */
471 struct sockaddr __user
*addr
;
478 struct user_msghdr __user
*umsg
;
484 struct io_buffer
*kbuf
;
490 bool ignore_nonblock
;
491 struct filename
*filename
;
493 unsigned long nofile
;
496 struct io_files_update
{
522 struct epoll_event event
;
526 struct file
*file_out
;
527 struct file
*file_in
;
534 struct io_provide_buf
{
548 const char __user
*filename
;
549 struct statx __user
*buffer
;
561 struct filename
*oldpath
;
562 struct filename
*newpath
;
570 struct filename
*filename
;
573 struct io_completion
{
575 struct list_head list
;
579 struct io_async_connect
{
580 struct sockaddr_storage address
;
583 struct io_async_msghdr
{
584 struct iovec fast_iov
[UIO_FASTIOV
];
586 struct sockaddr __user
*uaddr
;
588 struct sockaddr_storage addr
;
592 struct iovec fast_iov
[UIO_FASTIOV
];
593 const struct iovec
*free_iovec
;
594 struct iov_iter iter
;
596 struct wait_page_queue wpq
;
600 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
601 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
602 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
603 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
604 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
605 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
611 REQ_F_LINK_TIMEOUT_BIT
,
613 REQ_F_NEED_CLEANUP_BIT
,
615 REQ_F_BUFFER_SELECTED_BIT
,
616 REQ_F_NO_FILE_TABLE_BIT
,
617 REQ_F_WORK_INITIALIZED_BIT
,
618 REQ_F_LTIMEOUT_ACTIVE_BIT
,
620 /* not a real bit, just to check we're not overflowing the space */
626 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
627 /* drain existing IO first */
628 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
630 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
631 /* doesn't sever on completion < 0 */
632 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
634 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
635 /* IOSQE_BUFFER_SELECT */
636 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
638 /* fail rest of links */
639 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
640 /* on inflight list */
641 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
642 /* read/write uses file position */
643 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
644 /* must not punt to workers */
645 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
646 /* has or had linked timeout */
647 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
649 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
651 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
652 /* already went through poll handler */
653 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
654 /* buffer already selected */
655 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
656 /* doesn't need file table for this request */
657 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
658 /* io_wq_work is initialized */
659 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
660 /* linked timeout is active, i.e. prepared by link's head */
661 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
665 struct io_poll_iocb poll
;
666 struct io_poll_iocb
*double_poll
;
670 * NOTE! Each of the iocb union members has the file pointer
671 * as the first entry in their struct definition. So you can
672 * access the file pointer through any of the sub-structs,
673 * or directly as just 'ki_filp' in this struct.
679 struct io_poll_iocb poll
;
680 struct io_poll_remove poll_remove
;
681 struct io_accept accept
;
683 struct io_cancel cancel
;
684 struct io_timeout timeout
;
685 struct io_timeout_rem timeout_rem
;
686 struct io_connect connect
;
687 struct io_sr_msg sr_msg
;
689 struct io_close close
;
690 struct io_files_update files_update
;
691 struct io_fadvise fadvise
;
692 struct io_madvise madvise
;
693 struct io_epoll epoll
;
694 struct io_splice splice
;
695 struct io_provide_buf pbuf
;
696 struct io_statx statx
;
697 struct io_shutdown shutdown
;
698 struct io_rename rename
;
699 struct io_unlink unlink
;
700 /* use only after cleaning per-op data, see io_clean_op() */
701 struct io_completion
compl;
704 /* opcode allocated if it needs to store data for async defer */
707 /* polled IO has completed */
713 struct io_ring_ctx
*ctx
;
716 struct task_struct
*task
;
719 struct io_kiocb
*link
;
720 struct percpu_ref
*fixed_file_refs
;
723 * 1. used with ctx->iopoll_list with reads/writes
724 * 2. to track reqs with ->files (see io_op_def::file_table)
726 struct list_head inflight_entry
;
727 struct callback_head task_work
;
728 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
729 struct hlist_node hash_node
;
730 struct async_poll
*apoll
;
731 struct io_wq_work work
;
734 struct io_defer_entry
{
735 struct list_head list
;
736 struct io_kiocb
*req
;
740 #define IO_IOPOLL_BATCH 8
742 struct io_comp_state
{
744 struct list_head list
;
745 struct io_ring_ctx
*ctx
;
748 struct io_submit_state
{
749 struct blk_plug plug
;
752 * io_kiocb alloc cache
754 void *reqs
[IO_IOPOLL_BATCH
];
755 unsigned int free_reqs
;
760 * Batch completion logic
762 struct io_comp_state comp
;
765 * File reference cache
769 unsigned int file_refs
;
770 unsigned int ios_left
;
774 /* needs req->file assigned */
775 unsigned needs_file
: 1;
776 /* don't fail if file grab fails */
777 unsigned needs_file_no_error
: 1;
778 /* hash wq insertion if file is a regular file */
779 unsigned hash_reg_file
: 1;
780 /* unbound wq insertion if file is a non-regular file */
781 unsigned unbound_nonreg_file
: 1;
782 /* opcode is not supported by this kernel */
783 unsigned not_supported
: 1;
784 /* set if opcode supports polled "wait" */
786 unsigned pollout
: 1;
787 /* op supports buffer selection */
788 unsigned buffer_select
: 1;
789 /* must always have async data allocated */
790 unsigned needs_async_data
: 1;
791 /* should block plug */
793 /* size of async data needed, if any */
794 unsigned short async_size
;
798 static const struct io_op_def io_op_defs
[] = {
799 [IORING_OP_NOP
] = {},
800 [IORING_OP_READV
] = {
802 .unbound_nonreg_file
= 1,
805 .needs_async_data
= 1,
807 .async_size
= sizeof(struct io_async_rw
),
808 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
810 [IORING_OP_WRITEV
] = {
813 .unbound_nonreg_file
= 1,
815 .needs_async_data
= 1,
817 .async_size
= sizeof(struct io_async_rw
),
818 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
821 [IORING_OP_FSYNC
] = {
823 .work_flags
= IO_WQ_WORK_BLKCG
,
825 [IORING_OP_READ_FIXED
] = {
827 .unbound_nonreg_file
= 1,
830 .async_size
= sizeof(struct io_async_rw
),
831 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
833 [IORING_OP_WRITE_FIXED
] = {
836 .unbound_nonreg_file
= 1,
839 .async_size
= sizeof(struct io_async_rw
),
840 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
|
843 [IORING_OP_POLL_ADD
] = {
845 .unbound_nonreg_file
= 1,
847 [IORING_OP_POLL_REMOVE
] = {},
848 [IORING_OP_SYNC_FILE_RANGE
] = {
850 .work_flags
= IO_WQ_WORK_BLKCG
,
852 [IORING_OP_SENDMSG
] = {
854 .unbound_nonreg_file
= 1,
856 .needs_async_data
= 1,
857 .async_size
= sizeof(struct io_async_msghdr
),
858 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
860 [IORING_OP_RECVMSG
] = {
862 .unbound_nonreg_file
= 1,
865 .needs_async_data
= 1,
866 .async_size
= sizeof(struct io_async_msghdr
),
867 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
869 [IORING_OP_TIMEOUT
] = {
870 .needs_async_data
= 1,
871 .async_size
= sizeof(struct io_timeout_data
),
872 .work_flags
= IO_WQ_WORK_MM
,
874 [IORING_OP_TIMEOUT_REMOVE
] = {
875 /* used by timeout updates' prep() */
876 .work_flags
= IO_WQ_WORK_MM
,
878 [IORING_OP_ACCEPT
] = {
880 .unbound_nonreg_file
= 1,
882 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
,
884 [IORING_OP_ASYNC_CANCEL
] = {},
885 [IORING_OP_LINK_TIMEOUT
] = {
886 .needs_async_data
= 1,
887 .async_size
= sizeof(struct io_timeout_data
),
888 .work_flags
= IO_WQ_WORK_MM
,
890 [IORING_OP_CONNECT
] = {
892 .unbound_nonreg_file
= 1,
894 .needs_async_data
= 1,
895 .async_size
= sizeof(struct io_async_connect
),
896 .work_flags
= IO_WQ_WORK_MM
,
898 [IORING_OP_FALLOCATE
] = {
900 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
,
902 [IORING_OP_OPENAT
] = {
903 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
|
904 IO_WQ_WORK_FS
| IO_WQ_WORK_MM
,
906 [IORING_OP_CLOSE
] = {
908 .needs_file_no_error
= 1,
909 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
,
911 [IORING_OP_FILES_UPDATE
] = {
912 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
,
914 [IORING_OP_STATX
] = {
915 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
|
916 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
920 .unbound_nonreg_file
= 1,
924 .async_size
= sizeof(struct io_async_rw
),
925 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
927 [IORING_OP_WRITE
] = {
929 .unbound_nonreg_file
= 1,
932 .async_size
= sizeof(struct io_async_rw
),
933 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
936 [IORING_OP_FADVISE
] = {
938 .work_flags
= IO_WQ_WORK_BLKCG
,
940 [IORING_OP_MADVISE
] = {
941 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
945 .unbound_nonreg_file
= 1,
947 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
951 .unbound_nonreg_file
= 1,
954 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
956 [IORING_OP_OPENAT2
] = {
957 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_FS
|
958 IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
960 [IORING_OP_EPOLL_CTL
] = {
961 .unbound_nonreg_file
= 1,
962 .work_flags
= IO_WQ_WORK_FILES
,
964 [IORING_OP_SPLICE
] = {
967 .unbound_nonreg_file
= 1,
968 .work_flags
= IO_WQ_WORK_BLKCG
,
970 [IORING_OP_PROVIDE_BUFFERS
] = {},
971 [IORING_OP_REMOVE_BUFFERS
] = {},
975 .unbound_nonreg_file
= 1,
977 [IORING_OP_SHUTDOWN
] = {
980 [IORING_OP_RENAMEAT
] = {
981 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
|
982 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
984 [IORING_OP_UNLINKAT
] = {
985 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
|
986 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
990 enum io_mem_account
{
995 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
996 struct io_comp_state
*cs
);
997 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
998 static void io_put_req(struct io_kiocb
*req
);
999 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
1000 static void io_double_put_req(struct io_kiocb
*req
);
1001 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
1002 static void __io_queue_linked_timeout(struct io_kiocb
*req
);
1003 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1004 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
1005 struct io_uring_files_update
*ip
,
1007 static void __io_clean_op(struct io_kiocb
*req
);
1008 static struct file
*io_file_get(struct io_submit_state
*state
,
1009 struct io_kiocb
*req
, int fd
, bool fixed
);
1010 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
);
1011 static void io_file_put_work(struct work_struct
*work
);
1013 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
1014 struct iovec
**iovec
, struct iov_iter
*iter
,
1016 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
1017 const struct iovec
*fast_iov
,
1018 struct iov_iter
*iter
, bool force
);
1020 static struct kmem_cache
*req_cachep
;
1022 static const struct file_operations io_uring_fops
;
1024 struct sock
*io_uring_get_socket(struct file
*file
)
1026 #if defined(CONFIG_UNIX)
1027 if (file
->f_op
== &io_uring_fops
) {
1028 struct io_ring_ctx
*ctx
= file
->private_data
;
1030 return ctx
->ring_sock
->sk
;
1035 EXPORT_SYMBOL(io_uring_get_socket
);
1037 #define io_for_each_link(pos, head) \
1038 for (pos = (head); pos; pos = pos->link)
1040 static inline void io_clean_op(struct io_kiocb
*req
)
1042 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
|
1047 static inline void io_set_resource_node(struct io_kiocb
*req
)
1049 struct io_ring_ctx
*ctx
= req
->ctx
;
1051 if (!req
->fixed_file_refs
) {
1052 req
->fixed_file_refs
= &ctx
->file_data
->node
->refs
;
1053 percpu_ref_get(req
->fixed_file_refs
);
1057 static bool io_match_task(struct io_kiocb
*head
,
1058 struct task_struct
*task
,
1059 struct files_struct
*files
)
1061 struct io_kiocb
*req
;
1063 if (task
&& head
->task
!= task
)
1068 io_for_each_link(req
, head
) {
1069 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
1070 (req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1071 req
->work
.identity
->files
== files
)
1077 static void io_sq_thread_drop_mm_files(void)
1079 struct files_struct
*files
= current
->files
;
1080 struct mm_struct
*mm
= current
->mm
;
1083 kthread_unuse_mm(mm
);
1088 struct nsproxy
*nsproxy
= current
->nsproxy
;
1091 current
->files
= NULL
;
1092 current
->nsproxy
= NULL
;
1093 task_unlock(current
);
1094 put_files_struct(files
);
1095 put_nsproxy(nsproxy
);
1099 static int __io_sq_thread_acquire_files(struct io_ring_ctx
*ctx
)
1101 if (!current
->files
) {
1102 struct files_struct
*files
;
1103 struct nsproxy
*nsproxy
;
1105 task_lock(ctx
->sqo_task
);
1106 files
= ctx
->sqo_task
->files
;
1108 task_unlock(ctx
->sqo_task
);
1111 atomic_inc(&files
->count
);
1112 get_nsproxy(ctx
->sqo_task
->nsproxy
);
1113 nsproxy
= ctx
->sqo_task
->nsproxy
;
1114 task_unlock(ctx
->sqo_task
);
1117 current
->files
= files
;
1118 current
->nsproxy
= nsproxy
;
1119 task_unlock(current
);
1124 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
1126 struct mm_struct
*mm
;
1131 /* Should never happen */
1132 if (unlikely(!(ctx
->flags
& IORING_SETUP_SQPOLL
)))
1135 task_lock(ctx
->sqo_task
);
1136 mm
= ctx
->sqo_task
->mm
;
1137 if (unlikely(!mm
|| !mmget_not_zero(mm
)))
1139 task_unlock(ctx
->sqo_task
);
1149 static int io_sq_thread_acquire_mm_files(struct io_ring_ctx
*ctx
,
1150 struct io_kiocb
*req
)
1152 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1155 if (def
->work_flags
& IO_WQ_WORK_MM
) {
1156 ret
= __io_sq_thread_acquire_mm(ctx
);
1161 if (def
->needs_file
|| (def
->work_flags
& IO_WQ_WORK_FILES
)) {
1162 ret
= __io_sq_thread_acquire_files(ctx
);
1170 static void io_sq_thread_associate_blkcg(struct io_ring_ctx
*ctx
,
1171 struct cgroup_subsys_state
**cur_css
)
1174 #ifdef CONFIG_BLK_CGROUP
1175 /* puts the old one when swapping */
1176 if (*cur_css
!= ctx
->sqo_blkcg_css
) {
1177 kthread_associate_blkcg(ctx
->sqo_blkcg_css
);
1178 *cur_css
= ctx
->sqo_blkcg_css
;
1183 static void io_sq_thread_unassociate_blkcg(void)
1185 #ifdef CONFIG_BLK_CGROUP
1186 kthread_associate_blkcg(NULL
);
1190 static inline void req_set_fail_links(struct io_kiocb
*req
)
1192 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1193 req
->flags
|= REQ_F_FAIL_LINK
;
1197 * None of these are dereferenced, they are simply used to check if any of
1198 * them have changed. If we're under current and check they are still the
1199 * same, we're fine to grab references to them for actual out-of-line use.
1201 static void io_init_identity(struct io_identity
*id
)
1203 id
->files
= current
->files
;
1204 id
->mm
= current
->mm
;
1205 #ifdef CONFIG_BLK_CGROUP
1207 id
->blkcg_css
= blkcg_css();
1210 id
->creds
= current_cred();
1211 id
->nsproxy
= current
->nsproxy
;
1212 id
->fs
= current
->fs
;
1213 id
->fsize
= rlimit(RLIMIT_FSIZE
);
1215 id
->loginuid
= current
->loginuid
;
1216 id
->sessionid
= current
->sessionid
;
1218 refcount_set(&id
->count
, 1);
1221 static inline void __io_req_init_async(struct io_kiocb
*req
)
1223 memset(&req
->work
, 0, sizeof(req
->work
));
1224 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1228 * Note: must call io_req_init_async() for the first time you
1229 * touch any members of io_wq_work.
1231 static inline void io_req_init_async(struct io_kiocb
*req
)
1233 struct io_uring_task
*tctx
= current
->io_uring
;
1235 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1238 __io_req_init_async(req
);
1240 /* Grab a ref if this isn't our static identity */
1241 req
->work
.identity
= tctx
->identity
;
1242 if (tctx
->identity
!= &tctx
->__identity
)
1243 refcount_inc(&req
->work
.identity
->count
);
1246 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
1248 return ctx
->flags
& IORING_SETUP_SQPOLL
;
1251 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1253 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1255 complete(&ctx
->ref_comp
);
1258 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1260 return !req
->timeout
.off
;
1263 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1265 struct io_ring_ctx
*ctx
;
1268 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1272 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
1273 if (!ctx
->fallback_req
)
1277 * Use 5 bits less than the max cq entries, that should give us around
1278 * 32 entries per hash list if totally full and uniformly spread.
1280 hash_bits
= ilog2(p
->cq_entries
);
1284 ctx
->cancel_hash_bits
= hash_bits
;
1285 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1287 if (!ctx
->cancel_hash
)
1289 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1291 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1292 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1295 ctx
->flags
= p
->flags
;
1296 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1297 INIT_LIST_HEAD(&ctx
->sqd_list
);
1298 init_waitqueue_head(&ctx
->cq_wait
);
1299 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1300 init_completion(&ctx
->ref_comp
);
1301 init_completion(&ctx
->sq_thread_comp
);
1302 idr_init(&ctx
->io_buffer_idr
);
1303 idr_init(&ctx
->personality_idr
);
1304 mutex_init(&ctx
->uring_lock
);
1305 init_waitqueue_head(&ctx
->wait
);
1306 spin_lock_init(&ctx
->completion_lock
);
1307 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1308 INIT_LIST_HEAD(&ctx
->defer_list
);
1309 INIT_LIST_HEAD(&ctx
->timeout_list
);
1310 spin_lock_init(&ctx
->inflight_lock
);
1311 INIT_LIST_HEAD(&ctx
->inflight_list
);
1312 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
1313 init_llist_head(&ctx
->file_put_llist
);
1316 if (ctx
->fallback_req
)
1317 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
1318 kfree(ctx
->cancel_hash
);
1323 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1325 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1326 struct io_ring_ctx
*ctx
= req
->ctx
;
1328 return seq
!= ctx
->cached_cq_tail
1329 + READ_ONCE(ctx
->cached_cq_overflow
);
1335 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1337 struct io_rings
*rings
= ctx
->rings
;
1339 /* order cqe stores with ring update */
1340 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1342 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1343 wake_up_interruptible(&ctx
->cq_wait
);
1344 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1348 static void io_put_identity(struct io_uring_task
*tctx
, struct io_kiocb
*req
)
1350 if (req
->work
.identity
== &tctx
->__identity
)
1352 if (refcount_dec_and_test(&req
->work
.identity
->count
))
1353 kfree(req
->work
.identity
);
1356 static void io_req_clean_work(struct io_kiocb
*req
)
1358 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1361 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1363 if (req
->work
.flags
& IO_WQ_WORK_MM
) {
1364 mmdrop(req
->work
.identity
->mm
);
1365 req
->work
.flags
&= ~IO_WQ_WORK_MM
;
1367 #ifdef CONFIG_BLK_CGROUP
1368 if (req
->work
.flags
& IO_WQ_WORK_BLKCG
) {
1369 css_put(req
->work
.identity
->blkcg_css
);
1370 req
->work
.flags
&= ~IO_WQ_WORK_BLKCG
;
1373 if (req
->work
.flags
& IO_WQ_WORK_CREDS
) {
1374 put_cred(req
->work
.identity
->creds
);
1375 req
->work
.flags
&= ~IO_WQ_WORK_CREDS
;
1377 if (req
->work
.flags
& IO_WQ_WORK_FS
) {
1378 struct fs_struct
*fs
= req
->work
.identity
->fs
;
1380 spin_lock(&req
->work
.identity
->fs
->lock
);
1383 spin_unlock(&req
->work
.identity
->fs
->lock
);
1386 req
->work
.flags
&= ~IO_WQ_WORK_FS
;
1389 io_put_identity(req
->task
->io_uring
, req
);
1393 * Create a private copy of io_identity, since some fields don't match
1394 * the current context.
1396 static bool io_identity_cow(struct io_kiocb
*req
)
1398 struct io_uring_task
*tctx
= current
->io_uring
;
1399 const struct cred
*creds
= NULL
;
1400 struct io_identity
*id
;
1402 if (req
->work
.flags
& IO_WQ_WORK_CREDS
)
1403 creds
= req
->work
.identity
->creds
;
1405 id
= kmemdup(req
->work
.identity
, sizeof(*id
), GFP_KERNEL
);
1406 if (unlikely(!id
)) {
1407 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1412 * We can safely just re-init the creds we copied Either the field
1413 * matches the current one, or we haven't grabbed it yet. The only
1414 * exception is ->creds, through registered personalities, so handle
1415 * that one separately.
1417 io_init_identity(id
);
1421 /* add one for this request */
1422 refcount_inc(&id
->count
);
1424 /* drop tctx and req identity references, if needed */
1425 if (tctx
->identity
!= &tctx
->__identity
&&
1426 refcount_dec_and_test(&tctx
->identity
->count
))
1427 kfree(tctx
->identity
);
1428 if (req
->work
.identity
!= &tctx
->__identity
&&
1429 refcount_dec_and_test(&req
->work
.identity
->count
))
1430 kfree(req
->work
.identity
);
1432 req
->work
.identity
= id
;
1433 tctx
->identity
= id
;
1437 static bool io_grab_identity(struct io_kiocb
*req
)
1439 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1440 struct io_identity
*id
= req
->work
.identity
;
1441 struct io_ring_ctx
*ctx
= req
->ctx
;
1443 if (def
->work_flags
& IO_WQ_WORK_FSIZE
) {
1444 if (id
->fsize
!= rlimit(RLIMIT_FSIZE
))
1446 req
->work
.flags
|= IO_WQ_WORK_FSIZE
;
1448 #ifdef CONFIG_BLK_CGROUP
1449 if (!(req
->work
.flags
& IO_WQ_WORK_BLKCG
) &&
1450 (def
->work_flags
& IO_WQ_WORK_BLKCG
)) {
1452 if (id
->blkcg_css
!= blkcg_css()) {
1457 * This should be rare, either the cgroup is dying or the task
1458 * is moving cgroups. Just punt to root for the handful of ios.
1460 if (css_tryget_online(id
->blkcg_css
))
1461 req
->work
.flags
|= IO_WQ_WORK_BLKCG
;
1465 if (!(req
->work
.flags
& IO_WQ_WORK_CREDS
)) {
1466 if (id
->creds
!= current_cred())
1468 get_cred(id
->creds
);
1469 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
1472 if (!uid_eq(current
->loginuid
, id
->loginuid
) ||
1473 current
->sessionid
!= id
->sessionid
)
1476 if (!(req
->work
.flags
& IO_WQ_WORK_FS
) &&
1477 (def
->work_flags
& IO_WQ_WORK_FS
)) {
1478 if (current
->fs
!= id
->fs
)
1480 spin_lock(&id
->fs
->lock
);
1481 if (!id
->fs
->in_exec
) {
1483 req
->work
.flags
|= IO_WQ_WORK_FS
;
1485 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1487 spin_unlock(¤t
->fs
->lock
);
1489 if (!(req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1490 (def
->work_flags
& IO_WQ_WORK_FILES
) &&
1491 !(req
->flags
& REQ_F_NO_FILE_TABLE
)) {
1492 if (id
->files
!= current
->files
||
1493 id
->nsproxy
!= current
->nsproxy
)
1495 atomic_inc(&id
->files
->count
);
1496 get_nsproxy(id
->nsproxy
);
1497 req
->flags
|= REQ_F_INFLIGHT
;
1499 spin_lock_irq(&ctx
->inflight_lock
);
1500 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
1501 spin_unlock_irq(&ctx
->inflight_lock
);
1502 req
->work
.flags
|= IO_WQ_WORK_FILES
;
1508 static void io_prep_async_work(struct io_kiocb
*req
)
1510 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1511 struct io_ring_ctx
*ctx
= req
->ctx
;
1512 struct io_identity
*id
;
1514 io_req_init_async(req
);
1515 id
= req
->work
.identity
;
1517 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1518 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1520 if (req
->flags
& REQ_F_ISREG
) {
1521 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1522 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1524 if (def
->unbound_nonreg_file
)
1525 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1528 /* ->mm can never change on us */
1529 if (!(req
->work
.flags
& IO_WQ_WORK_MM
) &&
1530 (def
->work_flags
& IO_WQ_WORK_MM
)) {
1532 req
->work
.flags
|= IO_WQ_WORK_MM
;
1535 /* if we fail grabbing identity, we must COW, regrab, and retry */
1536 if (io_grab_identity(req
))
1539 if (!io_identity_cow(req
))
1542 /* can't fail at this point */
1543 if (!io_grab_identity(req
))
1547 static void io_prep_async_link(struct io_kiocb
*req
)
1549 struct io_kiocb
*cur
;
1551 io_for_each_link(cur
, req
)
1552 io_prep_async_work(cur
);
1555 static struct io_kiocb
*__io_queue_async_work(struct io_kiocb
*req
)
1557 struct io_ring_ctx
*ctx
= req
->ctx
;
1558 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1560 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1561 &req
->work
, req
->flags
);
1562 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1566 static void io_queue_async_work(struct io_kiocb
*req
)
1568 struct io_kiocb
*link
;
1570 /* init ->work of the whole link before punting */
1571 io_prep_async_link(req
);
1572 link
= __io_queue_async_work(req
);
1575 io_queue_linked_timeout(link
);
1578 static void io_kill_timeout(struct io_kiocb
*req
)
1580 struct io_timeout_data
*io
= req
->async_data
;
1583 ret
= hrtimer_try_to_cancel(&io
->timer
);
1585 atomic_set(&req
->ctx
->cq_timeouts
,
1586 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1587 list_del_init(&req
->timeout
.list
);
1588 io_cqring_fill_event(req
, 0);
1589 io_put_req_deferred(req
, 1);
1594 * Returns true if we found and killed one or more timeouts
1596 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
1597 struct files_struct
*files
)
1599 struct io_kiocb
*req
, *tmp
;
1602 spin_lock_irq(&ctx
->completion_lock
);
1603 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
1604 if (io_match_task(req
, tsk
, files
)) {
1605 io_kill_timeout(req
);
1609 spin_unlock_irq(&ctx
->completion_lock
);
1610 return canceled
!= 0;
1613 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1616 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1617 struct io_defer_entry
, list
);
1618 struct io_kiocb
*link
;
1620 if (req_need_defer(de
->req
, de
->seq
))
1622 list_del_init(&de
->list
);
1623 /* punt-init is done before queueing for defer */
1624 link
= __io_queue_async_work(de
->req
);
1626 __io_queue_linked_timeout(link
);
1627 /* drop submission reference */
1628 io_put_req_deferred(link
, 1);
1631 } while (!list_empty(&ctx
->defer_list
));
1634 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1636 while (!list_empty(&ctx
->timeout_list
)) {
1637 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1638 struct io_kiocb
, timeout
.list
);
1640 if (io_is_timeout_noseq(req
))
1642 if (req
->timeout
.target_seq
!= ctx
->cached_cq_tail
1643 - atomic_read(&ctx
->cq_timeouts
))
1646 list_del_init(&req
->timeout
.list
);
1647 io_kill_timeout(req
);
1651 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1653 io_flush_timeouts(ctx
);
1654 __io_commit_cqring(ctx
);
1656 if (unlikely(!list_empty(&ctx
->defer_list
)))
1657 __io_queue_deferred(ctx
);
1660 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1662 struct io_rings
*r
= ctx
->rings
;
1664 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1667 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1669 struct io_rings
*rings
= ctx
->rings
;
1672 tail
= ctx
->cached_cq_tail
;
1674 * writes to the cq entry need to come after reading head; the
1675 * control dependency is enough as we're using WRITE_ONCE to
1678 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1681 ctx
->cached_cq_tail
++;
1682 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1685 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1689 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1691 if (!ctx
->eventfd_async
)
1693 return io_wq_current_is_worker();
1696 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1698 if (waitqueue_active(&ctx
->wait
))
1699 wake_up(&ctx
->wait
);
1700 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1701 wake_up(&ctx
->sq_data
->wait
);
1702 if (io_should_trigger_evfd(ctx
))
1703 eventfd_signal(ctx
->cq_ev_fd
, 1);
1706 static void io_cqring_mark_overflow(struct io_ring_ctx
*ctx
)
1708 if (list_empty(&ctx
->cq_overflow_list
)) {
1709 clear_bit(0, &ctx
->sq_check_overflow
);
1710 clear_bit(0, &ctx
->cq_check_overflow
);
1711 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1715 /* Returns true if there are no backlogged entries after the flush */
1716 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1717 struct task_struct
*tsk
,
1718 struct files_struct
*files
)
1720 struct io_rings
*rings
= ctx
->rings
;
1721 struct io_kiocb
*req
, *tmp
;
1722 struct io_uring_cqe
*cqe
;
1723 unsigned long flags
;
1727 if (list_empty_careful(&ctx
->cq_overflow_list
))
1729 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1730 rings
->cq_ring_entries
))
1734 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1736 /* if force is set, the ring is going away. always drop after that */
1738 ctx
->cq_overflow_flushed
= 1;
1741 list_for_each_entry_safe(req
, tmp
, &ctx
->cq_overflow_list
, compl.list
) {
1742 if (!io_match_task(req
, tsk
, files
))
1745 cqe
= io_get_cqring(ctx
);
1749 list_move(&req
->compl.list
, &list
);
1751 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1752 WRITE_ONCE(cqe
->res
, req
->result
);
1753 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1755 ctx
->cached_cq_overflow
++;
1756 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1757 ctx
->cached_cq_overflow
);
1761 io_commit_cqring(ctx
);
1762 io_cqring_mark_overflow(ctx
);
1764 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1765 io_cqring_ev_posted(ctx
);
1767 while (!list_empty(&list
)) {
1768 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1769 list_del(&req
->compl.list
);
1776 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1778 struct io_ring_ctx
*ctx
= req
->ctx
;
1779 struct io_uring_cqe
*cqe
;
1781 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1784 * If we can't get a cq entry, userspace overflowed the
1785 * submission (by quite a lot). Increment the overflow count in
1788 cqe
= io_get_cqring(ctx
);
1790 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1791 WRITE_ONCE(cqe
->res
, res
);
1792 WRITE_ONCE(cqe
->flags
, cflags
);
1793 } else if (ctx
->cq_overflow_flushed
||
1794 atomic_read(&req
->task
->io_uring
->in_idle
)) {
1796 * If we're in ring overflow flush mode, or in task cancel mode,
1797 * then we cannot store the request for later flushing, we need
1798 * to drop it on the floor.
1800 ctx
->cached_cq_overflow
++;
1801 WRITE_ONCE(ctx
->rings
->cq_overflow
, ctx
->cached_cq_overflow
);
1803 if (list_empty(&ctx
->cq_overflow_list
)) {
1804 set_bit(0, &ctx
->sq_check_overflow
);
1805 set_bit(0, &ctx
->cq_check_overflow
);
1806 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1810 req
->compl.cflags
= cflags
;
1811 refcount_inc(&req
->refs
);
1812 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1816 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1818 __io_cqring_fill_event(req
, res
, 0);
1821 static void io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1823 struct io_ring_ctx
*ctx
= req
->ctx
;
1824 unsigned long flags
;
1826 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1827 __io_cqring_fill_event(req
, res
, cflags
);
1828 io_commit_cqring(ctx
);
1829 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1831 io_cqring_ev_posted(ctx
);
1834 static void io_submit_flush_completions(struct io_comp_state
*cs
)
1836 struct io_ring_ctx
*ctx
= cs
->ctx
;
1838 spin_lock_irq(&ctx
->completion_lock
);
1839 while (!list_empty(&cs
->list
)) {
1840 struct io_kiocb
*req
;
1842 req
= list_first_entry(&cs
->list
, struct io_kiocb
, compl.list
);
1843 list_del(&req
->compl.list
);
1844 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
1847 * io_free_req() doesn't care about completion_lock unless one
1848 * of these flags is set. REQ_F_WORK_INITIALIZED is in the list
1849 * because of a potential deadlock with req->work.fs->lock
1851 if (req
->flags
& (REQ_F_FAIL_LINK
|REQ_F_LINK_TIMEOUT
1852 |REQ_F_WORK_INITIALIZED
)) {
1853 spin_unlock_irq(&ctx
->completion_lock
);
1855 spin_lock_irq(&ctx
->completion_lock
);
1860 io_commit_cqring(ctx
);
1861 spin_unlock_irq(&ctx
->completion_lock
);
1863 io_cqring_ev_posted(ctx
);
1867 static void __io_req_complete(struct io_kiocb
*req
, long res
, unsigned cflags
,
1868 struct io_comp_state
*cs
)
1871 io_cqring_add_event(req
, res
, cflags
);
1876 req
->compl.cflags
= cflags
;
1877 list_add_tail(&req
->compl.list
, &cs
->list
);
1879 io_submit_flush_completions(cs
);
1883 static void io_req_complete(struct io_kiocb
*req
, long res
)
1885 __io_req_complete(req
, res
, 0, NULL
);
1888 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1890 return req
== (struct io_kiocb
*)
1891 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1894 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1896 struct io_kiocb
*req
;
1898 req
= ctx
->fallback_req
;
1899 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1905 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1906 struct io_submit_state
*state
)
1908 if (!state
->free_reqs
) {
1909 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1913 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1914 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1917 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1918 * retry single alloc to be on the safe side.
1920 if (unlikely(ret
<= 0)) {
1921 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1922 if (!state
->reqs
[0])
1926 state
->free_reqs
= ret
;
1930 return state
->reqs
[state
->free_reqs
];
1932 return io_get_fallback_req(ctx
);
1935 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1942 static void io_dismantle_req(struct io_kiocb
*req
)
1946 if (req
->async_data
)
1947 kfree(req
->async_data
);
1949 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1950 if (req
->fixed_file_refs
)
1951 percpu_ref_put(req
->fixed_file_refs
);
1952 io_req_clean_work(req
);
1955 static void __io_free_req(struct io_kiocb
*req
)
1957 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1958 struct io_ring_ctx
*ctx
= req
->ctx
;
1960 io_dismantle_req(req
);
1962 percpu_counter_dec(&tctx
->inflight
);
1963 if (atomic_read(&tctx
->in_idle
))
1964 wake_up(&tctx
->wait
);
1965 put_task_struct(req
->task
);
1967 if (likely(!io_is_fallback_req(req
)))
1968 kmem_cache_free(req_cachep
, req
);
1970 clear_bit_unlock(0, (unsigned long *) &ctx
->fallback_req
);
1971 percpu_ref_put(&ctx
->refs
);
1974 static inline void io_remove_next_linked(struct io_kiocb
*req
)
1976 struct io_kiocb
*nxt
= req
->link
;
1978 req
->link
= nxt
->link
;
1982 static void io_kill_linked_timeout(struct io_kiocb
*req
)
1984 struct io_ring_ctx
*ctx
= req
->ctx
;
1985 struct io_kiocb
*link
;
1986 bool cancelled
= false;
1987 unsigned long flags
;
1989 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1993 * Can happen if a linked timeout fired and link had been like
1994 * req -> link t-out -> link t-out [-> ...]
1996 if (link
&& (link
->flags
& REQ_F_LTIMEOUT_ACTIVE
)) {
1997 struct io_timeout_data
*io
= link
->async_data
;
2000 io_remove_next_linked(req
);
2001 link
->timeout
.head
= NULL
;
2002 ret
= hrtimer_try_to_cancel(&io
->timer
);
2004 io_cqring_fill_event(link
, -ECANCELED
);
2005 io_commit_cqring(ctx
);
2009 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
2010 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
2013 io_cqring_ev_posted(ctx
);
2019 static void io_fail_links(struct io_kiocb
*req
)
2021 struct io_kiocb
*link
, *nxt
;
2022 struct io_ring_ctx
*ctx
= req
->ctx
;
2023 unsigned long flags
;
2025 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
2033 trace_io_uring_fail_link(req
, link
);
2034 io_cqring_fill_event(link
, -ECANCELED
);
2037 * It's ok to free under spinlock as they're not linked anymore,
2038 * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
2041 if (link
->flags
& REQ_F_WORK_INITIALIZED
)
2042 io_put_req_deferred(link
, 2);
2044 io_double_put_req(link
);
2047 io_commit_cqring(ctx
);
2048 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
2050 io_cqring_ev_posted(ctx
);
2053 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
2055 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
2056 io_kill_linked_timeout(req
);
2059 * If LINK is set, we have dependent requests in this chain. If we
2060 * didn't fail this request, queue the first one up, moving any other
2061 * dependencies to the next request. In case of failure, fail the rest
2064 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
))) {
2065 struct io_kiocb
*nxt
= req
->link
;
2074 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
2076 if (likely(!(req
->link
) && !(req
->flags
& REQ_F_LINK_TIMEOUT
)))
2078 return __io_req_find_next(req
);
2081 static int io_req_task_work_add(struct io_kiocb
*req
)
2083 struct task_struct
*tsk
= req
->task
;
2084 struct io_ring_ctx
*ctx
= req
->ctx
;
2085 enum task_work_notify_mode notify
;
2088 if (tsk
->flags
& PF_EXITING
)
2092 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2093 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2094 * processing task_work. There's no reliable way to tell if TWA_RESUME
2098 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
))
2099 notify
= TWA_SIGNAL
;
2101 ret
= task_work_add(tsk
, &req
->task_work
, notify
);
2103 wake_up_process(tsk
);
2108 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
2110 struct io_ring_ctx
*ctx
= req
->ctx
;
2112 spin_lock_irq(&ctx
->completion_lock
);
2113 io_cqring_fill_event(req
, error
);
2114 io_commit_cqring(ctx
);
2115 spin_unlock_irq(&ctx
->completion_lock
);
2117 io_cqring_ev_posted(ctx
);
2118 req_set_fail_links(req
);
2119 io_double_put_req(req
);
2122 static void io_req_task_cancel(struct callback_head
*cb
)
2124 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2125 struct io_ring_ctx
*ctx
= req
->ctx
;
2127 __io_req_task_cancel(req
, -ECANCELED
);
2128 percpu_ref_put(&ctx
->refs
);
2131 static void __io_req_task_submit(struct io_kiocb
*req
)
2133 struct io_ring_ctx
*ctx
= req
->ctx
;
2135 if (!__io_sq_thread_acquire_mm(ctx
) &&
2136 !__io_sq_thread_acquire_files(ctx
)) {
2137 mutex_lock(&ctx
->uring_lock
);
2138 __io_queue_sqe(req
, NULL
);
2139 mutex_unlock(&ctx
->uring_lock
);
2141 __io_req_task_cancel(req
, -EFAULT
);
2145 static void io_req_task_submit(struct callback_head
*cb
)
2147 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2148 struct io_ring_ctx
*ctx
= req
->ctx
;
2150 __io_req_task_submit(req
);
2151 percpu_ref_put(&ctx
->refs
);
2154 static void io_req_task_queue(struct io_kiocb
*req
)
2158 init_task_work(&req
->task_work
, io_req_task_submit
);
2159 percpu_ref_get(&req
->ctx
->refs
);
2161 ret
= io_req_task_work_add(req
);
2162 if (unlikely(ret
)) {
2163 struct task_struct
*tsk
;
2165 init_task_work(&req
->task_work
, io_req_task_cancel
);
2166 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2167 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2168 wake_up_process(tsk
);
2172 static inline void io_queue_next(struct io_kiocb
*req
)
2174 struct io_kiocb
*nxt
= io_req_find_next(req
);
2177 io_req_task_queue(nxt
);
2180 static void io_free_req(struct io_kiocb
*req
)
2187 void *reqs
[IO_IOPOLL_BATCH
];
2190 struct task_struct
*task
;
2194 static inline void io_init_req_batch(struct req_batch
*rb
)
2201 static void __io_req_free_batch_flush(struct io_ring_ctx
*ctx
,
2202 struct req_batch
*rb
)
2204 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
2205 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
2209 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2210 struct req_batch
*rb
)
2213 __io_req_free_batch_flush(ctx
, rb
);
2215 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2217 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2218 put_task_struct_many(rb
->task
, rb
->task_refs
);
2223 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
)
2225 if (unlikely(io_is_fallback_req(req
))) {
2231 if (req
->task
!= rb
->task
) {
2233 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2235 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2236 put_task_struct_many(rb
->task
, rb
->task_refs
);
2238 rb
->task
= req
->task
;
2243 io_dismantle_req(req
);
2244 rb
->reqs
[rb
->to_free
++] = req
;
2245 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
2246 __io_req_free_batch_flush(req
->ctx
, rb
);
2250 * Drop reference to request, return next in chain (if there is one) if this
2251 * was the last reference to this request.
2253 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2255 struct io_kiocb
*nxt
= NULL
;
2257 if (refcount_dec_and_test(&req
->refs
)) {
2258 nxt
= io_req_find_next(req
);
2264 static void io_put_req(struct io_kiocb
*req
)
2266 if (refcount_dec_and_test(&req
->refs
))
2270 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2272 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2277 static void io_free_req_deferred(struct io_kiocb
*req
)
2281 init_task_work(&req
->task_work
, io_put_req_deferred_cb
);
2282 ret
= io_req_task_work_add(req
);
2283 if (unlikely(ret
)) {
2284 struct task_struct
*tsk
;
2286 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2287 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2288 wake_up_process(tsk
);
2292 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2294 if (refcount_sub_and_test(refs
, &req
->refs
))
2295 io_free_req_deferred(req
);
2298 static struct io_wq_work
*io_steal_work(struct io_kiocb
*req
)
2300 struct io_kiocb
*nxt
;
2303 * A ref is owned by io-wq in which context we're. So, if that's the
2304 * last one, it's safe to steal next work. False negatives are Ok,
2305 * it just will be re-punted async in io_put_work()
2307 if (refcount_read(&req
->refs
) != 1)
2310 nxt
= io_req_find_next(req
);
2311 return nxt
? &nxt
->work
: NULL
;
2314 static void io_double_put_req(struct io_kiocb
*req
)
2316 /* drop both submit and complete references */
2317 if (refcount_sub_and_test(2, &req
->refs
))
2321 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
2323 struct io_rings
*rings
= ctx
->rings
;
2325 if (test_bit(0, &ctx
->cq_check_overflow
)) {
2327 * noflush == true is from the waitqueue handler, just ensure
2328 * we wake up the task, and the next invocation will flush the
2329 * entries. We cannot safely to it from here.
2334 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
2337 /* See comment at the top of this file */
2339 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
2342 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2344 struct io_rings
*rings
= ctx
->rings
;
2346 /* make sure SQ entry isn't read before tail */
2347 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2350 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2352 unsigned int cflags
;
2354 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2355 cflags
|= IORING_CQE_F_BUFFER
;
2356 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2361 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2363 struct io_buffer
*kbuf
;
2365 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2366 return io_put_kbuf(req
, kbuf
);
2369 static inline bool io_run_task_work(void)
2372 * Not safe to run on exiting task, and the task_work handling will
2373 * not add work to such a task.
2375 if (unlikely(current
->flags
& PF_EXITING
))
2377 if (current
->task_works
) {
2378 __set_current_state(TASK_RUNNING
);
2386 static void io_iopoll_queue(struct list_head
*again
)
2388 struct io_kiocb
*req
;
2391 req
= list_first_entry(again
, struct io_kiocb
, inflight_entry
);
2392 list_del(&req
->inflight_entry
);
2393 __io_complete_rw(req
, -EAGAIN
, 0, NULL
);
2394 } while (!list_empty(again
));
2398 * Find and free completed poll iocbs
2400 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2401 struct list_head
*done
)
2403 struct req_batch rb
;
2404 struct io_kiocb
*req
;
2407 /* order with ->result store in io_complete_rw_iopoll() */
2410 io_init_req_batch(&rb
);
2411 while (!list_empty(done
)) {
2414 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2415 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2417 req
->iopoll_completed
= 0;
2418 list_move_tail(&req
->inflight_entry
, &again
);
2421 list_del(&req
->inflight_entry
);
2423 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2424 cflags
= io_put_rw_kbuf(req
);
2426 __io_cqring_fill_event(req
, req
->result
, cflags
);
2429 if (refcount_dec_and_test(&req
->refs
))
2430 io_req_free_batch(&rb
, req
);
2433 io_commit_cqring(ctx
);
2434 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
2435 io_cqring_ev_posted(ctx
);
2436 io_req_free_batch_finish(ctx
, &rb
);
2438 if (!list_empty(&again
))
2439 io_iopoll_queue(&again
);
2442 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2445 struct io_kiocb
*req
, *tmp
;
2451 * Only spin for completions if we don't have multiple devices hanging
2452 * off our complete list, and we're under the requested amount.
2454 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2457 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2458 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2461 * Move completed and retryable entries to our local lists.
2462 * If we find a request that requires polling, break out
2463 * and complete those lists first, if we have entries there.
2465 if (READ_ONCE(req
->iopoll_completed
)) {
2466 list_move_tail(&req
->inflight_entry
, &done
);
2469 if (!list_empty(&done
))
2472 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2476 /* iopoll may have completed current req */
2477 if (READ_ONCE(req
->iopoll_completed
))
2478 list_move_tail(&req
->inflight_entry
, &done
);
2485 if (!list_empty(&done
))
2486 io_iopoll_complete(ctx
, nr_events
, &done
);
2492 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2493 * non-spinning poll check - we'll still enter the driver poll loop, but only
2494 * as a non-spinning completion check.
2496 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2499 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2502 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2505 if (*nr_events
>= min
)
2513 * We can't just wait for polled events to come to us, we have to actively
2514 * find and complete them.
2516 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2518 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2521 mutex_lock(&ctx
->uring_lock
);
2522 while (!list_empty(&ctx
->iopoll_list
)) {
2523 unsigned int nr_events
= 0;
2525 io_do_iopoll(ctx
, &nr_events
, 0);
2527 /* let it sleep and repeat later if can't complete a request */
2531 * Ensure we allow local-to-the-cpu processing to take place,
2532 * in this case we need to ensure that we reap all events.
2533 * Also let task_work, etc. to progress by releasing the mutex
2535 if (need_resched()) {
2536 mutex_unlock(&ctx
->uring_lock
);
2538 mutex_lock(&ctx
->uring_lock
);
2541 mutex_unlock(&ctx
->uring_lock
);
2544 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2546 unsigned int nr_events
= 0;
2547 int iters
= 0, ret
= 0;
2550 * We disallow the app entering submit/complete with polling, but we
2551 * still need to lock the ring to prevent racing with polled issue
2552 * that got punted to a workqueue.
2554 mutex_lock(&ctx
->uring_lock
);
2557 * Don't enter poll loop if we already have events pending.
2558 * If we do, we can potentially be spinning for commands that
2559 * already triggered a CQE (eg in error).
2561 if (io_cqring_events(ctx
, false))
2565 * If a submit got punted to a workqueue, we can have the
2566 * application entering polling for a command before it gets
2567 * issued. That app will hold the uring_lock for the duration
2568 * of the poll right here, so we need to take a breather every
2569 * now and then to ensure that the issue has a chance to add
2570 * the poll to the issued list. Otherwise we can spin here
2571 * forever, while the workqueue is stuck trying to acquire the
2574 if (!(++iters
& 7)) {
2575 mutex_unlock(&ctx
->uring_lock
);
2577 mutex_lock(&ctx
->uring_lock
);
2580 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2584 } while (min
&& !nr_events
&& !need_resched());
2586 mutex_unlock(&ctx
->uring_lock
);
2590 static void kiocb_end_write(struct io_kiocb
*req
)
2593 * Tell lockdep we inherited freeze protection from submission
2596 if (req
->flags
& REQ_F_ISREG
) {
2597 struct inode
*inode
= file_inode(req
->file
);
2599 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2601 file_end_write(req
->file
);
2604 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
,
2605 struct io_comp_state
*cs
)
2607 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2610 if (kiocb
->ki_flags
& IOCB_WRITE
)
2611 kiocb_end_write(req
);
2613 if (res
!= req
->result
)
2614 req_set_fail_links(req
);
2615 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2616 cflags
= io_put_rw_kbuf(req
);
2617 __io_req_complete(req
, res
, cflags
, cs
);
2621 static bool io_resubmit_prep(struct io_kiocb
*req
, int error
)
2623 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2624 ssize_t ret
= -ECANCELED
;
2625 struct iov_iter iter
;
2633 switch (req
->opcode
) {
2634 case IORING_OP_READV
:
2635 case IORING_OP_READ_FIXED
:
2636 case IORING_OP_READ
:
2639 case IORING_OP_WRITEV
:
2640 case IORING_OP_WRITE_FIXED
:
2641 case IORING_OP_WRITE
:
2645 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2650 if (!req
->async_data
) {
2651 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2654 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, &iter
, false);
2662 req_set_fail_links(req
);
2667 static bool io_rw_reissue(struct io_kiocb
*req
, long res
)
2670 umode_t mode
= file_inode(req
->file
)->i_mode
;
2673 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2675 if ((res
!= -EAGAIN
&& res
!= -EOPNOTSUPP
) || io_wq_current_is_worker())
2678 ret
= io_sq_thread_acquire_mm_files(req
->ctx
, req
);
2680 if (io_resubmit_prep(req
, ret
)) {
2681 refcount_inc(&req
->refs
);
2682 io_queue_async_work(req
);
2690 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2691 struct io_comp_state
*cs
)
2693 if (!io_rw_reissue(req
, res
))
2694 io_complete_rw_common(&req
->rw
.kiocb
, res
, cs
);
2697 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2699 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2701 __io_complete_rw(req
, res
, res2
, NULL
);
2704 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2706 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2708 if (kiocb
->ki_flags
& IOCB_WRITE
)
2709 kiocb_end_write(req
);
2711 if (res
!= -EAGAIN
&& res
!= req
->result
)
2712 req_set_fail_links(req
);
2714 WRITE_ONCE(req
->result
, res
);
2715 /* order with io_poll_complete() checking ->result */
2717 WRITE_ONCE(req
->iopoll_completed
, 1);
2721 * After the iocb has been issued, it's safe to be found on the poll list.
2722 * Adding the kiocb to the list AFTER submission ensures that we don't
2723 * find it from a io_iopoll_getevents() thread before the issuer is done
2724 * accessing the kiocb cookie.
2726 static void io_iopoll_req_issued(struct io_kiocb
*req
, bool in_async
)
2728 struct io_ring_ctx
*ctx
= req
->ctx
;
2731 * Track whether we have multiple files in our lists. This will impact
2732 * how we do polling eventually, not spinning if we're on potentially
2733 * different devices.
2735 if (list_empty(&ctx
->iopoll_list
)) {
2736 ctx
->poll_multi_file
= false;
2737 } else if (!ctx
->poll_multi_file
) {
2738 struct io_kiocb
*list_req
;
2740 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2742 if (list_req
->file
!= req
->file
)
2743 ctx
->poll_multi_file
= true;
2747 * For fast devices, IO may have already completed. If it has, add
2748 * it to the front so we find it first.
2750 if (READ_ONCE(req
->iopoll_completed
))
2751 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2753 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2756 * If IORING_SETUP_SQPOLL is enabled, sqes are either handled in sq thread
2757 * task context or in io worker task context. If current task context is
2758 * sq thread, we don't need to check whether should wake up sq thread.
2760 if (in_async
&& (ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2761 wq_has_sleeper(&ctx
->sq_data
->wait
))
2762 wake_up(&ctx
->sq_data
->wait
);
2765 static inline void __io_state_file_put(struct io_submit_state
*state
)
2767 fput_many(state
->file
, state
->file_refs
);
2768 state
->file_refs
= 0;
2771 static inline void io_state_file_put(struct io_submit_state
*state
)
2773 if (state
->file_refs
)
2774 __io_state_file_put(state
);
2778 * Get as many references to a file as we have IOs left in this submission,
2779 * assuming most submissions are for one file, or at least that each file
2780 * has more than one submission.
2782 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2787 if (state
->file_refs
) {
2788 if (state
->fd
== fd
) {
2792 __io_state_file_put(state
);
2794 state
->file
= fget_many(fd
, state
->ios_left
);
2795 if (unlikely(!state
->file
))
2799 state
->file_refs
= state
->ios_left
- 1;
2803 static bool io_bdev_nowait(struct block_device
*bdev
)
2805 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2809 * If we tracked the file through the SCM inflight mechanism, we could support
2810 * any file. For now, just ensure that anything potentially problematic is done
2813 static bool io_file_supports_async(struct file
*file
, int rw
)
2815 umode_t mode
= file_inode(file
)->i_mode
;
2817 if (S_ISBLK(mode
)) {
2818 if (IS_ENABLED(CONFIG_BLOCK
) &&
2819 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2823 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2825 if (S_ISREG(mode
)) {
2826 if (IS_ENABLED(CONFIG_BLOCK
) &&
2827 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2828 file
->f_op
!= &io_uring_fops
)
2833 /* any ->read/write should understand O_NONBLOCK */
2834 if (file
->f_flags
& O_NONBLOCK
)
2837 if (!(file
->f_mode
& FMODE_NOWAIT
))
2841 return file
->f_op
->read_iter
!= NULL
;
2843 return file
->f_op
->write_iter
!= NULL
;
2846 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2848 struct io_ring_ctx
*ctx
= req
->ctx
;
2849 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2853 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2854 req
->flags
|= REQ_F_ISREG
;
2856 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2857 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2858 req
->flags
|= REQ_F_CUR_POS
;
2859 kiocb
->ki_pos
= req
->file
->f_pos
;
2861 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2862 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2863 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2867 ioprio
= READ_ONCE(sqe
->ioprio
);
2869 ret
= ioprio_check_cap(ioprio
);
2873 kiocb
->ki_ioprio
= ioprio
;
2875 kiocb
->ki_ioprio
= get_current_ioprio();
2877 /* don't allow async punt if RWF_NOWAIT was requested */
2878 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2879 req
->flags
|= REQ_F_NOWAIT
;
2881 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2882 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2883 !kiocb
->ki_filp
->f_op
->iopoll
)
2886 kiocb
->ki_flags
|= IOCB_HIPRI
;
2887 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2888 req
->iopoll_completed
= 0;
2890 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2892 kiocb
->ki_complete
= io_complete_rw
;
2895 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2896 req
->rw
.len
= READ_ONCE(sqe
->len
);
2897 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2901 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2907 case -ERESTARTNOINTR
:
2908 case -ERESTARTNOHAND
:
2909 case -ERESTART_RESTARTBLOCK
:
2911 * We can't just restart the syscall, since previously
2912 * submitted sqes may already be in progress. Just fail this
2918 kiocb
->ki_complete(kiocb
, ret
, 0);
2922 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2923 struct io_comp_state
*cs
)
2925 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2926 struct io_async_rw
*io
= req
->async_data
;
2928 /* add previously done IO, if any */
2929 if (io
&& io
->bytes_done
> 0) {
2931 ret
= io
->bytes_done
;
2933 ret
+= io
->bytes_done
;
2936 if (req
->flags
& REQ_F_CUR_POS
)
2937 req
->file
->f_pos
= kiocb
->ki_pos
;
2938 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2939 __io_complete_rw(req
, ret
, 0, cs
);
2941 io_rw_done(kiocb
, ret
);
2944 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2945 struct iov_iter
*iter
)
2947 struct io_ring_ctx
*ctx
= req
->ctx
;
2948 size_t len
= req
->rw
.len
;
2949 struct io_mapped_ubuf
*imu
;
2950 u16 index
, buf_index
= req
->buf_index
;
2954 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2956 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2957 imu
= &ctx
->user_bufs
[index
];
2958 buf_addr
= req
->rw
.addr
;
2961 if (buf_addr
+ len
< buf_addr
)
2963 /* not inside the mapped region */
2964 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2968 * May not be a start of buffer, set size appropriately
2969 * and advance us to the beginning.
2971 offset
= buf_addr
- imu
->ubuf
;
2972 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2976 * Don't use iov_iter_advance() here, as it's really slow for
2977 * using the latter parts of a big fixed buffer - it iterates
2978 * over each segment manually. We can cheat a bit here, because
2981 * 1) it's a BVEC iter, we set it up
2982 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2983 * first and last bvec
2985 * So just find our index, and adjust the iterator afterwards.
2986 * If the offset is within the first bvec (or the whole first
2987 * bvec, just use iov_iter_advance(). This makes it easier
2988 * since we can just skip the first segment, which may not
2989 * be PAGE_SIZE aligned.
2991 const struct bio_vec
*bvec
= imu
->bvec
;
2993 if (offset
<= bvec
->bv_len
) {
2994 iov_iter_advance(iter
, offset
);
2996 unsigned long seg_skip
;
2998 /* skip first vec */
2999 offset
-= bvec
->bv_len
;
3000 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
3002 iter
->bvec
= bvec
+ seg_skip
;
3003 iter
->nr_segs
-= seg_skip
;
3004 iter
->count
-= bvec
->bv_len
+ offset
;
3005 iter
->iov_offset
= offset
& ~PAGE_MASK
;
3012 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3015 mutex_unlock(&ctx
->uring_lock
);
3018 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3021 * "Normal" inline submissions always hold the uring_lock, since we
3022 * grab it from the system call. Same is true for the SQPOLL offload.
3023 * The only exception is when we've detached the request and issue it
3024 * from an async worker thread, grab the lock for that case.
3027 mutex_lock(&ctx
->uring_lock
);
3030 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
3031 int bgid
, struct io_buffer
*kbuf
,
3034 struct io_buffer
*head
;
3036 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
3039 io_ring_submit_lock(req
->ctx
, needs_lock
);
3041 lockdep_assert_held(&req
->ctx
->uring_lock
);
3043 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
3045 if (!list_empty(&head
->list
)) {
3046 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
3048 list_del(&kbuf
->list
);
3051 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
3053 if (*len
> kbuf
->len
)
3056 kbuf
= ERR_PTR(-ENOBUFS
);
3059 io_ring_submit_unlock(req
->ctx
, needs_lock
);
3064 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
3067 struct io_buffer
*kbuf
;
3070 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3071 bgid
= req
->buf_index
;
3072 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
3075 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
3076 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3077 return u64_to_user_ptr(kbuf
->addr
);
3080 #ifdef CONFIG_COMPAT
3081 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
3084 struct compat_iovec __user
*uiov
;
3085 compat_ssize_t clen
;
3089 uiov
= u64_to_user_ptr(req
->rw
.addr
);
3090 if (!access_ok(uiov
, sizeof(*uiov
)))
3092 if (__get_user(clen
, &uiov
->iov_len
))
3098 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3100 return PTR_ERR(buf
);
3101 iov
[0].iov_base
= buf
;
3102 iov
[0].iov_len
= (compat_size_t
) len
;
3107 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3110 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
3114 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3117 len
= iov
[0].iov_len
;
3120 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3122 return PTR_ERR(buf
);
3123 iov
[0].iov_base
= buf
;
3124 iov
[0].iov_len
= len
;
3128 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3131 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3132 struct io_buffer
*kbuf
;
3134 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3135 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3136 iov
[0].iov_len
= kbuf
->len
;
3141 else if (req
->rw
.len
> 1)
3144 #ifdef CONFIG_COMPAT
3145 if (req
->ctx
->compat
)
3146 return io_compat_import(req
, iov
, needs_lock
);
3149 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3152 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
3153 struct iovec
**iovec
, struct iov_iter
*iter
,
3156 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3157 size_t sqe_len
= req
->rw
.len
;
3161 opcode
= req
->opcode
;
3162 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3164 return io_import_fixed(req
, rw
, iter
);
3167 /* buffer index only valid with fixed read/write, or buffer select */
3168 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3171 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3172 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3173 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3175 return PTR_ERR(buf
);
3176 req
->rw
.len
= sqe_len
;
3179 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3184 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3185 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3187 ret
= (*iovec
)->iov_len
;
3188 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
3194 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3198 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3200 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3204 * For files that don't have ->read_iter() and ->write_iter(), handle them
3205 * by looping over ->read() or ->write() manually.
3207 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3209 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3210 struct file
*file
= req
->file
;
3214 * Don't support polled IO through this interface, and we can't
3215 * support non-blocking either. For the latter, this just causes
3216 * the kiocb to be handled from an async context.
3218 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3220 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3223 while (iov_iter_count(iter
)) {
3227 if (!iov_iter_is_bvec(iter
)) {
3228 iovec
= iov_iter_iovec(iter
);
3230 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3231 iovec
.iov_len
= req
->rw
.len
;
3235 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3236 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3238 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3239 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3248 if (nr
!= iovec
.iov_len
)
3252 iov_iter_advance(iter
, nr
);
3258 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3259 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3261 struct io_async_rw
*rw
= req
->async_data
;
3263 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3264 rw
->free_iovec
= iovec
;
3266 /* can only be fixed buffers, no need to do anything */
3267 if (iov_iter_is_bvec(iter
))
3270 unsigned iov_off
= 0;
3272 rw
->iter
.iov
= rw
->fast_iov
;
3273 if (iter
->iov
!= fast_iov
) {
3274 iov_off
= iter
->iov
- fast_iov
;
3275 rw
->iter
.iov
+= iov_off
;
3277 if (rw
->fast_iov
!= fast_iov
)
3278 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3279 sizeof(struct iovec
) * iter
->nr_segs
);
3281 req
->flags
|= REQ_F_NEED_CLEANUP
;
3285 static inline int __io_alloc_async_data(struct io_kiocb
*req
)
3287 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3288 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3289 return req
->async_data
== NULL
;
3292 static int io_alloc_async_data(struct io_kiocb
*req
)
3294 if (!io_op_defs
[req
->opcode
].needs_async_data
)
3297 return __io_alloc_async_data(req
);
3300 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3301 const struct iovec
*fast_iov
,
3302 struct iov_iter
*iter
, bool force
)
3304 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_data
)
3306 if (!req
->async_data
) {
3307 if (__io_alloc_async_data(req
))
3310 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3315 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3317 struct io_async_rw
*iorw
= req
->async_data
;
3318 struct iovec
*iov
= iorw
->fast_iov
;
3321 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3322 if (unlikely(ret
< 0))
3325 iorw
->bytes_done
= 0;
3326 iorw
->free_iovec
= iov
;
3328 req
->flags
|= REQ_F_NEED_CLEANUP
;
3332 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3336 ret
= io_prep_rw(req
, sqe
);
3340 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3343 /* either don't need iovec imported or already have it */
3344 if (!req
->async_data
)
3346 return io_rw_prep_async(req
, READ
);
3350 * This is our waitqueue callback handler, registered through lock_page_async()
3351 * when we initially tried to do the IO with the iocb armed our waitqueue.
3352 * This gets called when the page is unlocked, and we generally expect that to
3353 * happen when the page IO is completed and the page is now uptodate. This will
3354 * queue a task_work based retry of the operation, attempting to copy the data
3355 * again. If the latter fails because the page was NOT uptodate, then we will
3356 * do a thread based blocking retry of the operation. That's the unexpected
3359 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3360 int sync
, void *arg
)
3362 struct wait_page_queue
*wpq
;
3363 struct io_kiocb
*req
= wait
->private;
3364 struct wait_page_key
*key
= arg
;
3367 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3369 if (!wake_page_match(wpq
, key
))
3372 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3373 list_del_init(&wait
->entry
);
3375 init_task_work(&req
->task_work
, io_req_task_submit
);
3376 percpu_ref_get(&req
->ctx
->refs
);
3378 /* submit ref gets dropped, acquire a new one */
3379 refcount_inc(&req
->refs
);
3380 ret
= io_req_task_work_add(req
);
3381 if (unlikely(ret
)) {
3382 struct task_struct
*tsk
;
3384 /* queue just for cancelation */
3385 init_task_work(&req
->task_work
, io_req_task_cancel
);
3386 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
3387 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
3388 wake_up_process(tsk
);
3394 * This controls whether a given IO request should be armed for async page
3395 * based retry. If we return false here, the request is handed to the async
3396 * worker threads for retry. If we're doing buffered reads on a regular file,
3397 * we prepare a private wait_page_queue entry and retry the operation. This
3398 * will either succeed because the page is now uptodate and unlocked, or it
3399 * will register a callback when the page is unlocked at IO completion. Through
3400 * that callback, io_uring uses task_work to setup a retry of the operation.
3401 * That retry will attempt the buffered read again. The retry will generally
3402 * succeed, or in rare cases where it fails, we then fall back to using the
3403 * async worker threads for a blocking retry.
3405 static bool io_rw_should_retry(struct io_kiocb
*req
)
3407 struct io_async_rw
*rw
= req
->async_data
;
3408 struct wait_page_queue
*wait
= &rw
->wpq
;
3409 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3411 /* never retry for NOWAIT, we just complete with -EAGAIN */
3412 if (req
->flags
& REQ_F_NOWAIT
)
3415 /* Only for buffered IO */
3416 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3420 * just use poll if we can, and don't attempt if the fs doesn't
3421 * support callback based unlocks
3423 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3426 wait
->wait
.func
= io_async_buf_func
;
3427 wait
->wait
.private = req
;
3428 wait
->wait
.flags
= 0;
3429 INIT_LIST_HEAD(&wait
->wait
.entry
);
3430 kiocb
->ki_flags
|= IOCB_WAITQ
;
3431 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3432 kiocb
->ki_waitq
= wait
;
3436 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3438 if (req
->file
->f_op
->read_iter
)
3439 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3440 else if (req
->file
->f_op
->read
)
3441 return loop_rw_iter(READ
, req
, iter
);
3446 static int io_read(struct io_kiocb
*req
, bool force_nonblock
,
3447 struct io_comp_state
*cs
)
3449 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3450 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3451 struct iov_iter __iter
, *iter
= &__iter
;
3452 struct io_async_rw
*rw
= req
->async_data
;
3453 ssize_t io_size
, ret
, ret2
;
3460 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3464 io_size
= iov_iter_count(iter
);
3465 req
->result
= io_size
;
3468 /* Ensure we clear previously set non-block flag */
3469 if (!force_nonblock
)
3470 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3472 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3475 /* If the file doesn't support async, just async punt */
3476 no_async
= force_nonblock
&& !io_file_supports_async(req
->file
, READ
);
3480 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3484 ret
= io_iter_do_read(req
, iter
);
3488 } else if (ret
== -EIOCBQUEUED
) {
3491 } else if (ret
== -EAGAIN
) {
3492 /* IOPOLL retry should happen for io-wq threads */
3493 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3495 /* no retry on NONBLOCK marked file */
3496 if (req
->file
->f_flags
& O_NONBLOCK
)
3498 /* some cases will consume bytes even on error returns */
3499 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3502 } else if (ret
< 0) {
3503 /* make sure -ERESTARTSYS -> -EINTR is done */
3507 /* read it all, or we did blocking attempt. no retry. */
3508 if (!iov_iter_count(iter
) || !force_nonblock
||
3509 (req
->file
->f_flags
& O_NONBLOCK
))
3514 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3521 rw
= req
->async_data
;
3522 /* it's copied and will be cleaned with ->io */
3524 /* now use our persistent iterator, if we aren't already */
3527 rw
->bytes_done
+= ret
;
3528 /* if we can retry, do so with the callbacks armed */
3529 if (!io_rw_should_retry(req
)) {
3530 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3535 * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
3536 * get -EIOCBQUEUED, then we'll get a notification when the desired
3537 * page gets unlocked. We can also get a partial read here, and if we
3538 * do, then just retry at the new offset.
3540 ret
= io_iter_do_read(req
, iter
);
3541 if (ret
== -EIOCBQUEUED
) {
3544 } else if (ret
> 0 && ret
< io_size
) {
3545 /* we got some bytes, but not all. retry. */
3549 kiocb_done(kiocb
, ret
, cs
);
3552 /* it's reportedly faster than delegating the null check to kfree() */
3558 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3562 ret
= io_prep_rw(req
, sqe
);
3566 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3569 /* either don't need iovec imported or already have it */
3570 if (!req
->async_data
)
3572 return io_rw_prep_async(req
, WRITE
);
3575 static int io_write(struct io_kiocb
*req
, bool force_nonblock
,
3576 struct io_comp_state
*cs
)
3578 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3579 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3580 struct iov_iter __iter
, *iter
= &__iter
;
3581 struct io_async_rw
*rw
= req
->async_data
;
3582 ssize_t ret
, ret2
, io_size
;
3588 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3592 io_size
= iov_iter_count(iter
);
3593 req
->result
= io_size
;
3595 /* Ensure we clear previously set non-block flag */
3596 if (!force_nonblock
)
3597 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3599 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3601 /* If the file doesn't support async, just async punt */
3602 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3605 /* file path doesn't support NOWAIT for non-direct_IO */
3606 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3607 (req
->flags
& REQ_F_ISREG
))
3610 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3615 * Open-code file_start_write here to grab freeze protection,
3616 * which will be released by another thread in
3617 * io_complete_rw(). Fool lockdep by telling it the lock got
3618 * released so that it doesn't complain about the held lock when
3619 * we return to userspace.
3621 if (req
->flags
& REQ_F_ISREG
) {
3622 sb_start_write(file_inode(req
->file
)->i_sb
);
3623 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3626 kiocb
->ki_flags
|= IOCB_WRITE
;
3628 if (req
->file
->f_op
->write_iter
)
3629 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3630 else if (req
->file
->f_op
->write
)
3631 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3636 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3637 * retry them without IOCB_NOWAIT.
3639 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3641 /* no retry on NONBLOCK marked file */
3642 if (ret2
== -EAGAIN
&& (req
->file
->f_flags
& O_NONBLOCK
))
3644 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3645 /* IOPOLL retry should happen for io-wq threads */
3646 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3649 kiocb_done(kiocb
, ret2
, cs
);
3652 /* some cases will consume bytes even on error returns */
3653 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3654 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3659 /* it's reportedly faster than delegating the null check to kfree() */
3665 static int io_renameat_prep(struct io_kiocb
*req
,
3666 const struct io_uring_sqe
*sqe
)
3668 struct io_rename
*ren
= &req
->rename
;
3669 const char __user
*oldf
, *newf
;
3671 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3674 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3675 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3676 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3677 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3678 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3680 ren
->oldpath
= getname(oldf
);
3681 if (IS_ERR(ren
->oldpath
))
3682 return PTR_ERR(ren
->oldpath
);
3684 ren
->newpath
= getname(newf
);
3685 if (IS_ERR(ren
->newpath
)) {
3686 putname(ren
->oldpath
);
3687 return PTR_ERR(ren
->newpath
);
3690 req
->flags
|= REQ_F_NEED_CLEANUP
;
3694 static int io_renameat(struct io_kiocb
*req
, bool force_nonblock
)
3696 struct io_rename
*ren
= &req
->rename
;
3702 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3703 ren
->newpath
, ren
->flags
);
3705 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3707 req_set_fail_links(req
);
3708 io_req_complete(req
, ret
);
3712 static int io_unlinkat_prep(struct io_kiocb
*req
,
3713 const struct io_uring_sqe
*sqe
)
3715 struct io_unlink
*un
= &req
->unlink
;
3716 const char __user
*fname
;
3718 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3721 un
->dfd
= READ_ONCE(sqe
->fd
);
3723 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3724 if (un
->flags
& ~AT_REMOVEDIR
)
3727 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3728 un
->filename
= getname(fname
);
3729 if (IS_ERR(un
->filename
))
3730 return PTR_ERR(un
->filename
);
3732 req
->flags
|= REQ_F_NEED_CLEANUP
;
3736 static int io_unlinkat(struct io_kiocb
*req
, bool force_nonblock
)
3738 struct io_unlink
*un
= &req
->unlink
;
3744 if (un
->flags
& AT_REMOVEDIR
)
3745 ret
= do_rmdir(un
->dfd
, un
->filename
);
3747 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3749 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3751 req_set_fail_links(req
);
3752 io_req_complete(req
, ret
);
3756 static int io_shutdown_prep(struct io_kiocb
*req
,
3757 const struct io_uring_sqe
*sqe
)
3759 #if defined(CONFIG_NET)
3760 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3762 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3766 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3773 static int io_shutdown(struct io_kiocb
*req
, bool force_nonblock
)
3775 #if defined(CONFIG_NET)
3776 struct socket
*sock
;
3782 sock
= sock_from_file(req
->file
);
3783 if (unlikely(!sock
))
3786 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3787 io_req_complete(req
, ret
);
3794 static int __io_splice_prep(struct io_kiocb
*req
,
3795 const struct io_uring_sqe
*sqe
)
3797 struct io_splice
* sp
= &req
->splice
;
3798 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3800 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3804 sp
->len
= READ_ONCE(sqe
->len
);
3805 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3807 if (unlikely(sp
->flags
& ~valid_flags
))
3810 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3811 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3814 req
->flags
|= REQ_F_NEED_CLEANUP
;
3816 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3818 * Splice operation will be punted aync, and here need to
3819 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3821 io_req_init_async(req
);
3822 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3828 static int io_tee_prep(struct io_kiocb
*req
,
3829 const struct io_uring_sqe
*sqe
)
3831 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3833 return __io_splice_prep(req
, sqe
);
3836 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
3838 struct io_splice
*sp
= &req
->splice
;
3839 struct file
*in
= sp
->file_in
;
3840 struct file
*out
= sp
->file_out
;
3841 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3847 ret
= do_tee(in
, out
, sp
->len
, flags
);
3849 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3850 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3853 req_set_fail_links(req
);
3854 io_req_complete(req
, ret
);
3858 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3860 struct io_splice
* sp
= &req
->splice
;
3862 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3863 sp
->off_out
= READ_ONCE(sqe
->off
);
3864 return __io_splice_prep(req
, sqe
);
3867 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
3869 struct io_splice
*sp
= &req
->splice
;
3870 struct file
*in
= sp
->file_in
;
3871 struct file
*out
= sp
->file_out
;
3872 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3873 loff_t
*poff_in
, *poff_out
;
3879 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3880 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3883 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3885 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3886 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3889 req_set_fail_links(req
);
3890 io_req_complete(req
, ret
);
3895 * IORING_OP_NOP just posts a completion event, nothing else.
3897 static int io_nop(struct io_kiocb
*req
, struct io_comp_state
*cs
)
3899 struct io_ring_ctx
*ctx
= req
->ctx
;
3901 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3904 __io_req_complete(req
, 0, 0, cs
);
3908 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3910 struct io_ring_ctx
*ctx
= req
->ctx
;
3915 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3917 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3920 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3921 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3924 req
->sync
.off
= READ_ONCE(sqe
->off
);
3925 req
->sync
.len
= READ_ONCE(sqe
->len
);
3929 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
3931 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3934 /* fsync always requires a blocking context */
3938 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3939 end
> 0 ? end
: LLONG_MAX
,
3940 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3942 req_set_fail_links(req
);
3943 io_req_complete(req
, ret
);
3947 static int io_fallocate_prep(struct io_kiocb
*req
,
3948 const struct io_uring_sqe
*sqe
)
3950 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3952 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3955 req
->sync
.off
= READ_ONCE(sqe
->off
);
3956 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3957 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3961 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
3965 /* fallocate always requiring blocking context */
3968 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3971 req_set_fail_links(req
);
3972 io_req_complete(req
, ret
);
3976 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3978 const char __user
*fname
;
3981 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3983 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3986 /* open.how should be already initialised */
3987 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3988 req
->open
.how
.flags
|= O_LARGEFILE
;
3990 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3991 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3992 req
->open
.filename
= getname(fname
);
3993 if (IS_ERR(req
->open
.filename
)) {
3994 ret
= PTR_ERR(req
->open
.filename
);
3995 req
->open
.filename
= NULL
;
3998 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3999 req
->open
.ignore_nonblock
= false;
4000 req
->flags
|= REQ_F_NEED_CLEANUP
;
4004 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4008 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4010 mode
= READ_ONCE(sqe
->len
);
4011 flags
= READ_ONCE(sqe
->open_flags
);
4012 req
->open
.how
= build_open_how(flags
, mode
);
4013 return __io_openat_prep(req
, sqe
);
4016 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4018 struct open_how __user
*how
;
4022 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4024 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4025 len
= READ_ONCE(sqe
->len
);
4026 if (len
< OPEN_HOW_SIZE_VER0
)
4029 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
4034 return __io_openat_prep(req
, sqe
);
4037 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
4039 struct open_flags op
;
4043 if (force_nonblock
&& !req
->open
.ignore_nonblock
)
4046 ret
= build_open_flags(&req
->open
.how
, &op
);
4050 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
4054 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
4057 ret
= PTR_ERR(file
);
4059 * A work-around to ensure that /proc/self works that way
4060 * that it should - if we get -EOPNOTSUPP back, then assume
4061 * that proc_self_get_link() failed us because we're in async
4062 * context. We should be safe to retry this from the task
4063 * itself with force_nonblock == false set, as it should not
4064 * block on lookup. Would be nice to know this upfront and
4065 * avoid the async dance, but doesn't seem feasible.
4067 if (ret
== -EOPNOTSUPP
&& io_wq_current_is_worker()) {
4068 req
->open
.ignore_nonblock
= true;
4069 refcount_inc(&req
->refs
);
4070 io_req_task_queue(req
);
4074 fsnotify_open(file
);
4075 fd_install(ret
, file
);
4078 putname(req
->open
.filename
);
4079 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4081 req_set_fail_links(req
);
4082 io_req_complete(req
, ret
);
4086 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
4088 return io_openat2(req
, force_nonblock
);
4091 static int io_remove_buffers_prep(struct io_kiocb
*req
,
4092 const struct io_uring_sqe
*sqe
)
4094 struct io_provide_buf
*p
= &req
->pbuf
;
4097 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
4100 tmp
= READ_ONCE(sqe
->fd
);
4101 if (!tmp
|| tmp
> USHRT_MAX
)
4104 memset(p
, 0, sizeof(*p
));
4106 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4110 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
4111 int bgid
, unsigned nbufs
)
4115 /* shouldn't happen */
4119 /* the head kbuf is the list itself */
4120 while (!list_empty(&buf
->list
)) {
4121 struct io_buffer
*nxt
;
4123 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
4124 list_del(&nxt
->list
);
4131 idr_remove(&ctx
->io_buffer_idr
, bgid
);
4136 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
,
4137 struct io_comp_state
*cs
)
4139 struct io_provide_buf
*p
= &req
->pbuf
;
4140 struct io_ring_ctx
*ctx
= req
->ctx
;
4141 struct io_buffer
*head
;
4144 io_ring_submit_lock(ctx
, !force_nonblock
);
4146 lockdep_assert_held(&ctx
->uring_lock
);
4149 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
4151 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
4153 req_set_fail_links(req
);
4155 /* need to hold the lock to complete IOPOLL requests */
4156 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
4157 __io_req_complete(req
, ret
, 0, cs
);
4158 io_ring_submit_unlock(ctx
, !force_nonblock
);
4160 io_ring_submit_unlock(ctx
, !force_nonblock
);
4161 __io_req_complete(req
, ret
, 0, cs
);
4166 static int io_provide_buffers_prep(struct io_kiocb
*req
,
4167 const struct io_uring_sqe
*sqe
)
4169 struct io_provide_buf
*p
= &req
->pbuf
;
4172 if (sqe
->ioprio
|| sqe
->rw_flags
)
4175 tmp
= READ_ONCE(sqe
->fd
);
4176 if (!tmp
|| tmp
> USHRT_MAX
)
4179 p
->addr
= READ_ONCE(sqe
->addr
);
4180 p
->len
= READ_ONCE(sqe
->len
);
4182 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
4185 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4186 tmp
= READ_ONCE(sqe
->off
);
4187 if (tmp
> USHRT_MAX
)
4193 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
4195 struct io_buffer
*buf
;
4196 u64 addr
= pbuf
->addr
;
4197 int i
, bid
= pbuf
->bid
;
4199 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
4200 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
4205 buf
->len
= pbuf
->len
;
4210 INIT_LIST_HEAD(&buf
->list
);
4213 list_add_tail(&buf
->list
, &(*head
)->list
);
4217 return i
? i
: -ENOMEM
;
4220 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
,
4221 struct io_comp_state
*cs
)
4223 struct io_provide_buf
*p
= &req
->pbuf
;
4224 struct io_ring_ctx
*ctx
= req
->ctx
;
4225 struct io_buffer
*head
, *list
;
4228 io_ring_submit_lock(ctx
, !force_nonblock
);
4230 lockdep_assert_held(&ctx
->uring_lock
);
4232 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
4234 ret
= io_add_buffers(p
, &head
);
4239 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
4242 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4248 req_set_fail_links(req
);
4250 /* need to hold the lock to complete IOPOLL requests */
4251 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
4252 __io_req_complete(req
, ret
, 0, cs
);
4253 io_ring_submit_unlock(ctx
, !force_nonblock
);
4255 io_ring_submit_unlock(ctx
, !force_nonblock
);
4256 __io_req_complete(req
, ret
, 0, cs
);
4261 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4262 const struct io_uring_sqe
*sqe
)
4264 #if defined(CONFIG_EPOLL)
4265 if (sqe
->ioprio
|| sqe
->buf_index
)
4267 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4270 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4271 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4272 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4274 if (ep_op_has_event(req
->epoll
.op
)) {
4275 struct epoll_event __user
*ev
;
4277 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4278 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4288 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
,
4289 struct io_comp_state
*cs
)
4291 #if defined(CONFIG_EPOLL)
4292 struct io_epoll
*ie
= &req
->epoll
;
4295 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4296 if (force_nonblock
&& ret
== -EAGAIN
)
4300 req_set_fail_links(req
);
4301 __io_req_complete(req
, ret
, 0, cs
);
4308 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4310 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4311 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4313 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4316 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4317 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4318 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4325 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
4327 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4328 struct io_madvise
*ma
= &req
->madvise
;
4334 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4336 req_set_fail_links(req
);
4337 io_req_complete(req
, ret
);
4344 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4346 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4348 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4351 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4352 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4353 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4357 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
4359 struct io_fadvise
*fa
= &req
->fadvise
;
4362 if (force_nonblock
) {
4363 switch (fa
->advice
) {
4364 case POSIX_FADV_NORMAL
:
4365 case POSIX_FADV_RANDOM
:
4366 case POSIX_FADV_SEQUENTIAL
:
4373 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4375 req_set_fail_links(req
);
4376 io_req_complete(req
, ret
);
4380 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4382 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4384 if (sqe
->ioprio
|| sqe
->buf_index
)
4386 if (req
->flags
& REQ_F_FIXED_FILE
)
4389 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4390 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4391 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4392 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4393 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4398 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
4400 struct io_statx
*ctx
= &req
->statx
;
4403 if (force_nonblock
) {
4404 /* only need file table for an actual valid fd */
4405 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
4406 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4410 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4414 req_set_fail_links(req
);
4415 io_req_complete(req
, ret
);
4419 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4422 * If we queue this for async, it must not be cancellable. That would
4423 * leave the 'file' in an undeterminate state, and here need to modify
4424 * io_wq_work.flags, so initialize io_wq_work firstly.
4426 io_req_init_async(req
);
4427 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
4429 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4431 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4432 sqe
->rw_flags
|| sqe
->buf_index
)
4434 if (req
->flags
& REQ_F_FIXED_FILE
)
4437 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4438 if ((req
->file
&& req
->file
->f_op
== &io_uring_fops
))
4441 req
->close
.put_file
= NULL
;
4445 static int io_close(struct io_kiocb
*req
, bool force_nonblock
,
4446 struct io_comp_state
*cs
)
4448 struct io_close
*close
= &req
->close
;
4451 /* might be already done during nonblock submission */
4452 if (!close
->put_file
) {
4453 ret
= close_fd_get_file(close
->fd
, &close
->put_file
);
4455 return (ret
== -ENOENT
) ? -EBADF
: ret
;
4458 /* if the file has a flush method, be safe and punt to async */
4459 if (close
->put_file
->f_op
->flush
&& force_nonblock
) {
4460 /* was never set, but play safe */
4461 req
->flags
&= ~REQ_F_NOWAIT
;
4462 /* avoid grabbing files - we don't need the files */
4463 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4467 /* No ->flush() or already async, safely close from here */
4468 ret
= filp_close(close
->put_file
, req
->work
.identity
->files
);
4470 req_set_fail_links(req
);
4471 fput(close
->put_file
);
4472 close
->put_file
= NULL
;
4473 __io_req_complete(req
, ret
, 0, cs
);
4477 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4479 struct io_ring_ctx
*ctx
= req
->ctx
;
4484 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4486 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4489 req
->sync
.off
= READ_ONCE(sqe
->off
);
4490 req
->sync
.len
= READ_ONCE(sqe
->len
);
4491 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4495 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
4499 /* sync_file_range always requires a blocking context */
4503 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4506 req_set_fail_links(req
);
4507 io_req_complete(req
, ret
);
4511 #if defined(CONFIG_NET)
4512 static int io_setup_async_msg(struct io_kiocb
*req
,
4513 struct io_async_msghdr
*kmsg
)
4515 struct io_async_msghdr
*async_msg
= req
->async_data
;
4519 if (io_alloc_async_data(req
)) {
4520 if (kmsg
->iov
!= kmsg
->fast_iov
)
4524 async_msg
= req
->async_data
;
4525 req
->flags
|= REQ_F_NEED_CLEANUP
;
4526 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4530 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4531 struct io_async_msghdr
*iomsg
)
4533 iomsg
->iov
= iomsg
->fast_iov
;
4534 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4535 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4536 req
->sr_msg
.msg_flags
, &iomsg
->iov
);
4539 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4541 struct io_async_msghdr
*async_msg
= req
->async_data
;
4542 struct io_sr_msg
*sr
= &req
->sr_msg
;
4545 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4548 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4549 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4550 sr
->len
= READ_ONCE(sqe
->len
);
4552 #ifdef CONFIG_COMPAT
4553 if (req
->ctx
->compat
)
4554 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4557 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4559 ret
= io_sendmsg_copy_hdr(req
, async_msg
);
4561 req
->flags
|= REQ_F_NEED_CLEANUP
;
4565 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4566 struct io_comp_state
*cs
)
4568 struct io_async_msghdr iomsg
, *kmsg
;
4569 struct socket
*sock
;
4573 sock
= sock_from_file(req
->file
);
4574 if (unlikely(!sock
))
4577 if (req
->async_data
) {
4578 kmsg
= req
->async_data
;
4579 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4580 /* if iov is set, it's allocated already */
4582 kmsg
->iov
= kmsg
->fast_iov
;
4583 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4585 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4591 flags
= req
->sr_msg
.msg_flags
;
4592 if (flags
& MSG_DONTWAIT
)
4593 req
->flags
|= REQ_F_NOWAIT
;
4594 else if (force_nonblock
)
4595 flags
|= MSG_DONTWAIT
;
4597 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4598 if (force_nonblock
&& ret
== -EAGAIN
)
4599 return io_setup_async_msg(req
, kmsg
);
4600 if (ret
== -ERESTARTSYS
)
4603 if (kmsg
->iov
!= kmsg
->fast_iov
)
4605 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4607 req_set_fail_links(req
);
4608 __io_req_complete(req
, ret
, 0, cs
);
4612 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4613 struct io_comp_state
*cs
)
4615 struct io_sr_msg
*sr
= &req
->sr_msg
;
4618 struct socket
*sock
;
4622 sock
= sock_from_file(req
->file
);
4623 if (unlikely(!sock
))
4626 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4630 msg
.msg_name
= NULL
;
4631 msg
.msg_control
= NULL
;
4632 msg
.msg_controllen
= 0;
4633 msg
.msg_namelen
= 0;
4635 flags
= req
->sr_msg
.msg_flags
;
4636 if (flags
& MSG_DONTWAIT
)
4637 req
->flags
|= REQ_F_NOWAIT
;
4638 else if (force_nonblock
)
4639 flags
|= MSG_DONTWAIT
;
4641 msg
.msg_flags
= flags
;
4642 ret
= sock_sendmsg(sock
, &msg
);
4643 if (force_nonblock
&& ret
== -EAGAIN
)
4645 if (ret
== -ERESTARTSYS
)
4649 req_set_fail_links(req
);
4650 __io_req_complete(req
, ret
, 0, cs
);
4654 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4655 struct io_async_msghdr
*iomsg
)
4657 struct io_sr_msg
*sr
= &req
->sr_msg
;
4658 struct iovec __user
*uiov
;
4662 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4663 &iomsg
->uaddr
, &uiov
, &iov_len
);
4667 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4670 if (copy_from_user(iomsg
->iov
, uiov
, sizeof(*uiov
)))
4672 sr
->len
= iomsg
->iov
[0].iov_len
;
4673 iov_iter_init(&iomsg
->msg
.msg_iter
, READ
, iomsg
->iov
, 1,
4677 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4678 &iomsg
->iov
, &iomsg
->msg
.msg_iter
,
4687 #ifdef CONFIG_COMPAT
4688 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4689 struct io_async_msghdr
*iomsg
)
4691 struct compat_msghdr __user
*msg_compat
;
4692 struct io_sr_msg
*sr
= &req
->sr_msg
;
4693 struct compat_iovec __user
*uiov
;
4698 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4699 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4704 uiov
= compat_ptr(ptr
);
4705 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4706 compat_ssize_t clen
;
4710 if (!access_ok(uiov
, sizeof(*uiov
)))
4712 if (__get_user(clen
, &uiov
->iov_len
))
4717 iomsg
->iov
[0].iov_len
= clen
;
4720 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4721 UIO_FASTIOV
, &iomsg
->iov
,
4722 &iomsg
->msg
.msg_iter
, true);
4731 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4732 struct io_async_msghdr
*iomsg
)
4734 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4735 iomsg
->iov
= iomsg
->fast_iov
;
4737 #ifdef CONFIG_COMPAT
4738 if (req
->ctx
->compat
)
4739 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4742 return __io_recvmsg_copy_hdr(req
, iomsg
);
4745 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4748 struct io_sr_msg
*sr
= &req
->sr_msg
;
4749 struct io_buffer
*kbuf
;
4751 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4756 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4760 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4762 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4765 static int io_recvmsg_prep(struct io_kiocb
*req
,
4766 const struct io_uring_sqe
*sqe
)
4768 struct io_async_msghdr
*async_msg
= req
->async_data
;
4769 struct io_sr_msg
*sr
= &req
->sr_msg
;
4772 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4775 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4776 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4777 sr
->len
= READ_ONCE(sqe
->len
);
4778 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4780 #ifdef CONFIG_COMPAT
4781 if (req
->ctx
->compat
)
4782 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4785 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4787 ret
= io_recvmsg_copy_hdr(req
, async_msg
);
4789 req
->flags
|= REQ_F_NEED_CLEANUP
;
4793 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4794 struct io_comp_state
*cs
)
4796 struct io_async_msghdr iomsg
, *kmsg
;
4797 struct socket
*sock
;
4798 struct io_buffer
*kbuf
;
4800 int ret
, cflags
= 0;
4802 sock
= sock_from_file(req
->file
);
4803 if (unlikely(!sock
))
4806 if (req
->async_data
) {
4807 kmsg
= req
->async_data
;
4808 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4809 /* if iov is set, it's allocated already */
4811 kmsg
->iov
= kmsg
->fast_iov
;
4812 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4814 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4820 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4821 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4823 return PTR_ERR(kbuf
);
4824 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4825 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
4826 1, req
->sr_msg
.len
);
4829 flags
= req
->sr_msg
.msg_flags
;
4830 if (flags
& MSG_DONTWAIT
)
4831 req
->flags
|= REQ_F_NOWAIT
;
4832 else if (force_nonblock
)
4833 flags
|= MSG_DONTWAIT
;
4835 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4836 kmsg
->uaddr
, flags
);
4837 if (force_nonblock
&& ret
== -EAGAIN
)
4838 return io_setup_async_msg(req
, kmsg
);
4839 if (ret
== -ERESTARTSYS
)
4842 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4843 cflags
= io_put_recv_kbuf(req
);
4844 if (kmsg
->iov
!= kmsg
->fast_iov
)
4846 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4848 req_set_fail_links(req
);
4849 __io_req_complete(req
, ret
, cflags
, cs
);
4853 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4854 struct io_comp_state
*cs
)
4856 struct io_buffer
*kbuf
;
4857 struct io_sr_msg
*sr
= &req
->sr_msg
;
4859 void __user
*buf
= sr
->buf
;
4860 struct socket
*sock
;
4863 int ret
, cflags
= 0;
4865 sock
= sock_from_file(req
->file
);
4866 if (unlikely(!sock
))
4869 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4870 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4872 return PTR_ERR(kbuf
);
4873 buf
= u64_to_user_ptr(kbuf
->addr
);
4876 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4880 msg
.msg_name
= NULL
;
4881 msg
.msg_control
= NULL
;
4882 msg
.msg_controllen
= 0;
4883 msg
.msg_namelen
= 0;
4884 msg
.msg_iocb
= NULL
;
4887 flags
= req
->sr_msg
.msg_flags
;
4888 if (flags
& MSG_DONTWAIT
)
4889 req
->flags
|= REQ_F_NOWAIT
;
4890 else if (force_nonblock
)
4891 flags
|= MSG_DONTWAIT
;
4893 ret
= sock_recvmsg(sock
, &msg
, flags
);
4894 if (force_nonblock
&& ret
== -EAGAIN
)
4896 if (ret
== -ERESTARTSYS
)
4899 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4900 cflags
= io_put_recv_kbuf(req
);
4902 req_set_fail_links(req
);
4903 __io_req_complete(req
, ret
, cflags
, cs
);
4907 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4909 struct io_accept
*accept
= &req
->accept
;
4911 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4913 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4916 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4917 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4918 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4919 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4923 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4924 struct io_comp_state
*cs
)
4926 struct io_accept
*accept
= &req
->accept
;
4927 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4930 if (req
->file
->f_flags
& O_NONBLOCK
)
4931 req
->flags
|= REQ_F_NOWAIT
;
4933 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4934 accept
->addr_len
, accept
->flags
,
4936 if (ret
== -EAGAIN
&& force_nonblock
)
4939 if (ret
== -ERESTARTSYS
)
4941 req_set_fail_links(req
);
4943 __io_req_complete(req
, ret
, 0, cs
);
4947 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4949 struct io_connect
*conn
= &req
->connect
;
4950 struct io_async_connect
*io
= req
->async_data
;
4952 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4954 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4957 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4958 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4963 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4967 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4968 struct io_comp_state
*cs
)
4970 struct io_async_connect __io
, *io
;
4971 unsigned file_flags
;
4974 if (req
->async_data
) {
4975 io
= req
->async_data
;
4977 ret
= move_addr_to_kernel(req
->connect
.addr
,
4978 req
->connect
.addr_len
,
4985 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4987 ret
= __sys_connect_file(req
->file
, &io
->address
,
4988 req
->connect
.addr_len
, file_flags
);
4989 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4990 if (req
->async_data
)
4992 if (io_alloc_async_data(req
)) {
4996 io
= req
->async_data
;
4997 memcpy(req
->async_data
, &__io
, sizeof(__io
));
5000 if (ret
== -ERESTARTSYS
)
5004 req_set_fail_links(req
);
5005 __io_req_complete(req
, ret
, 0, cs
);
5008 #else /* !CONFIG_NET */
5009 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5014 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
5015 struct io_comp_state
*cs
)
5020 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
5021 struct io_comp_state
*cs
)
5026 static int io_recvmsg_prep(struct io_kiocb
*req
,
5027 const struct io_uring_sqe
*sqe
)
5032 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
5033 struct io_comp_state
*cs
)
5038 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
5039 struct io_comp_state
*cs
)
5044 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5049 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
5050 struct io_comp_state
*cs
)
5055 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5060 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
5061 struct io_comp_state
*cs
)
5065 #endif /* CONFIG_NET */
5067 struct io_poll_table
{
5068 struct poll_table_struct pt
;
5069 struct io_kiocb
*req
;
5073 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
5074 __poll_t mask
, task_work_func_t func
)
5078 /* for instances that support it check for an event match first: */
5079 if (mask
&& !(mask
& poll
->events
))
5082 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
5084 list_del_init(&poll
->wait
.entry
);
5087 init_task_work(&req
->task_work
, func
);
5088 percpu_ref_get(&req
->ctx
->refs
);
5091 * If this fails, then the task is exiting. When a task exits, the
5092 * work gets canceled, so just cancel this request as well instead
5093 * of executing it. We can't safely execute it anyway, as we may not
5094 * have the needed state needed for it anyway.
5096 ret
= io_req_task_work_add(req
);
5097 if (unlikely(ret
)) {
5098 struct task_struct
*tsk
;
5100 WRITE_ONCE(poll
->canceled
, true);
5101 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
5102 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
5103 wake_up_process(tsk
);
5108 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
5109 __acquires(&req
->ctx
->completion_lock
)
5111 struct io_ring_ctx
*ctx
= req
->ctx
;
5113 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5114 struct poll_table_struct pt
= { ._key
= poll
->events
};
5116 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
5119 spin_lock_irq(&ctx
->completion_lock
);
5120 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5121 add_wait_queue(poll
->head
, &poll
->wait
);
5128 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
5130 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
5131 if (req
->opcode
== IORING_OP_POLL_ADD
)
5132 return req
->async_data
;
5133 return req
->apoll
->double_poll
;
5136 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
5138 if (req
->opcode
== IORING_OP_POLL_ADD
)
5140 return &req
->apoll
->poll
;
5143 static void io_poll_remove_double(struct io_kiocb
*req
)
5145 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
5147 lockdep_assert_held(&req
->ctx
->completion_lock
);
5149 if (poll
&& poll
->head
) {
5150 struct wait_queue_head
*head
= poll
->head
;
5152 spin_lock(&head
->lock
);
5153 list_del_init(&poll
->wait
.entry
);
5154 if (poll
->wait
.private)
5155 refcount_dec(&req
->refs
);
5157 spin_unlock(&head
->lock
);
5161 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
5163 struct io_ring_ctx
*ctx
= req
->ctx
;
5165 io_poll_remove_double(req
);
5166 req
->poll
.done
= true;
5167 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
5168 io_commit_cqring(ctx
);
5171 static void io_poll_task_func(struct callback_head
*cb
)
5173 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5174 struct io_ring_ctx
*ctx
= req
->ctx
;
5175 struct io_kiocb
*nxt
;
5177 if (io_poll_rewait(req
, &req
->poll
)) {
5178 spin_unlock_irq(&ctx
->completion_lock
);
5180 hash_del(&req
->hash_node
);
5181 io_poll_complete(req
, req
->result
, 0);
5182 spin_unlock_irq(&ctx
->completion_lock
);
5184 nxt
= io_put_req_find_next(req
);
5185 io_cqring_ev_posted(ctx
);
5187 __io_req_task_submit(nxt
);
5190 percpu_ref_put(&ctx
->refs
);
5193 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
5194 int sync
, void *key
)
5196 struct io_kiocb
*req
= wait
->private;
5197 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
5198 __poll_t mask
= key_to_poll(key
);
5200 /* for instances that support it check for an event match first: */
5201 if (mask
&& !(mask
& poll
->events
))
5204 list_del_init(&wait
->entry
);
5206 if (poll
&& poll
->head
) {
5209 spin_lock(&poll
->head
->lock
);
5210 done
= list_empty(&poll
->wait
.entry
);
5212 list_del_init(&poll
->wait
.entry
);
5213 /* make sure double remove sees this as being gone */
5214 wait
->private = NULL
;
5215 spin_unlock(&poll
->head
->lock
);
5217 /* use wait func handler, so it matches the rq type */
5218 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5221 refcount_dec(&req
->refs
);
5225 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
5226 wait_queue_func_t wake_func
)
5230 poll
->canceled
= false;
5231 poll
->events
= events
;
5232 INIT_LIST_HEAD(&poll
->wait
.entry
);
5233 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5236 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5237 struct wait_queue_head
*head
,
5238 struct io_poll_iocb
**poll_ptr
)
5240 struct io_kiocb
*req
= pt
->req
;
5243 * If poll->head is already set, it's because the file being polled
5244 * uses multiple waitqueues for poll handling (eg one for read, one
5245 * for write). Setup a separate io_poll_iocb if this happens.
5247 if (unlikely(poll
->head
)) {
5248 struct io_poll_iocb
*poll_one
= poll
;
5250 /* already have a 2nd entry, fail a third attempt */
5252 pt
->error
= -EINVAL
;
5255 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5257 pt
->error
= -ENOMEM
;
5260 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5261 refcount_inc(&req
->refs
);
5262 poll
->wait
.private = req
;
5269 if (poll
->events
& EPOLLEXCLUSIVE
)
5270 add_wait_queue_exclusive(head
, &poll
->wait
);
5272 add_wait_queue(head
, &poll
->wait
);
5275 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5276 struct poll_table_struct
*p
)
5278 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5279 struct async_poll
*apoll
= pt
->req
->apoll
;
5281 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5284 static void io_async_task_func(struct callback_head
*cb
)
5286 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5287 struct async_poll
*apoll
= req
->apoll
;
5288 struct io_ring_ctx
*ctx
= req
->ctx
;
5290 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5292 if (io_poll_rewait(req
, &apoll
->poll
)) {
5293 spin_unlock_irq(&ctx
->completion_lock
);
5294 percpu_ref_put(&ctx
->refs
);
5298 /* If req is still hashed, it cannot have been canceled. Don't check. */
5299 if (hash_hashed(&req
->hash_node
))
5300 hash_del(&req
->hash_node
);
5302 io_poll_remove_double(req
);
5303 spin_unlock_irq(&ctx
->completion_lock
);
5305 if (!READ_ONCE(apoll
->poll
.canceled
))
5306 __io_req_task_submit(req
);
5308 __io_req_task_cancel(req
, -ECANCELED
);
5310 percpu_ref_put(&ctx
->refs
);
5311 kfree(apoll
->double_poll
);
5315 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5318 struct io_kiocb
*req
= wait
->private;
5319 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5321 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5324 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5327 static void io_poll_req_insert(struct io_kiocb
*req
)
5329 struct io_ring_ctx
*ctx
= req
->ctx
;
5330 struct hlist_head
*list
;
5332 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5333 hlist_add_head(&req
->hash_node
, list
);
5336 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5337 struct io_poll_iocb
*poll
,
5338 struct io_poll_table
*ipt
, __poll_t mask
,
5339 wait_queue_func_t wake_func
)
5340 __acquires(&ctx
->completion_lock
)
5342 struct io_ring_ctx
*ctx
= req
->ctx
;
5343 bool cancel
= false;
5345 INIT_HLIST_NODE(&req
->hash_node
);
5346 io_init_poll_iocb(poll
, mask
, wake_func
);
5347 poll
->file
= req
->file
;
5348 poll
->wait
.private = req
;
5350 ipt
->pt
._key
= mask
;
5352 ipt
->error
= -EINVAL
;
5354 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5356 spin_lock_irq(&ctx
->completion_lock
);
5357 if (likely(poll
->head
)) {
5358 spin_lock(&poll
->head
->lock
);
5359 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5365 if (mask
|| ipt
->error
)
5366 list_del_init(&poll
->wait
.entry
);
5368 WRITE_ONCE(poll
->canceled
, true);
5369 else if (!poll
->done
) /* actually waiting for an event */
5370 io_poll_req_insert(req
);
5371 spin_unlock(&poll
->head
->lock
);
5377 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5379 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5380 struct io_ring_ctx
*ctx
= req
->ctx
;
5381 struct async_poll
*apoll
;
5382 struct io_poll_table ipt
;
5386 if (!req
->file
|| !file_can_poll(req
->file
))
5388 if (req
->flags
& REQ_F_POLLED
)
5392 else if (def
->pollout
)
5396 /* if we can't nonblock try, then no point in arming a poll handler */
5397 if (!io_file_supports_async(req
->file
, rw
))
5400 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5401 if (unlikely(!apoll
))
5403 apoll
->double_poll
= NULL
;
5405 req
->flags
|= REQ_F_POLLED
;
5410 mask
|= POLLIN
| POLLRDNORM
;
5412 mask
|= POLLOUT
| POLLWRNORM
;
5414 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5415 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5416 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5419 mask
|= POLLERR
| POLLPRI
;
5421 ipt
.pt
._qproc
= io_async_queue_proc
;
5423 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5425 if (ret
|| ipt
.error
) {
5426 io_poll_remove_double(req
);
5427 spin_unlock_irq(&ctx
->completion_lock
);
5428 kfree(apoll
->double_poll
);
5432 spin_unlock_irq(&ctx
->completion_lock
);
5433 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5434 apoll
->poll
.events
);
5438 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5439 struct io_poll_iocb
*poll
)
5441 bool do_complete
= false;
5443 spin_lock(&poll
->head
->lock
);
5444 WRITE_ONCE(poll
->canceled
, true);
5445 if (!list_empty(&poll
->wait
.entry
)) {
5446 list_del_init(&poll
->wait
.entry
);
5449 spin_unlock(&poll
->head
->lock
);
5450 hash_del(&req
->hash_node
);
5454 static bool io_poll_remove_one(struct io_kiocb
*req
)
5458 io_poll_remove_double(req
);
5460 if (req
->opcode
== IORING_OP_POLL_ADD
) {
5461 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
5463 struct async_poll
*apoll
= req
->apoll
;
5465 /* non-poll requests have submit ref still */
5466 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
5469 kfree(apoll
->double_poll
);
5475 io_cqring_fill_event(req
, -ECANCELED
);
5476 io_commit_cqring(req
->ctx
);
5477 req_set_fail_links(req
);
5478 io_put_req_deferred(req
, 1);
5485 * Returns true if we found and killed one or more poll requests
5487 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5488 struct files_struct
*files
)
5490 struct hlist_node
*tmp
;
5491 struct io_kiocb
*req
;
5494 spin_lock_irq(&ctx
->completion_lock
);
5495 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5496 struct hlist_head
*list
;
5498 list
= &ctx
->cancel_hash
[i
];
5499 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5500 if (io_match_task(req
, tsk
, files
))
5501 posted
+= io_poll_remove_one(req
);
5504 spin_unlock_irq(&ctx
->completion_lock
);
5507 io_cqring_ev_posted(ctx
);
5512 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5514 struct hlist_head
*list
;
5515 struct io_kiocb
*req
;
5517 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5518 hlist_for_each_entry(req
, list
, hash_node
) {
5519 if (sqe_addr
!= req
->user_data
)
5521 if (io_poll_remove_one(req
))
5529 static int io_poll_remove_prep(struct io_kiocb
*req
,
5530 const struct io_uring_sqe
*sqe
)
5532 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5534 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5538 req
->poll_remove
.addr
= READ_ONCE(sqe
->addr
);
5543 * Find a running poll command that matches one specified in sqe->addr,
5544 * and remove it if found.
5546 static int io_poll_remove(struct io_kiocb
*req
)
5548 struct io_ring_ctx
*ctx
= req
->ctx
;
5551 spin_lock_irq(&ctx
->completion_lock
);
5552 ret
= io_poll_cancel(ctx
, req
->poll_remove
.addr
);
5553 spin_unlock_irq(&ctx
->completion_lock
);
5556 req_set_fail_links(req
);
5557 io_req_complete(req
, ret
);
5561 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5564 struct io_kiocb
*req
= wait
->private;
5565 struct io_poll_iocb
*poll
= &req
->poll
;
5567 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5570 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5571 struct poll_table_struct
*p
)
5573 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5575 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5578 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5580 struct io_poll_iocb
*poll
= &req
->poll
;
5583 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5585 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
5588 events
= READ_ONCE(sqe
->poll32_events
);
5590 events
= swahw32(events
);
5592 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
5593 (events
& EPOLLEXCLUSIVE
);
5597 static int io_poll_add(struct io_kiocb
*req
)
5599 struct io_poll_iocb
*poll
= &req
->poll
;
5600 struct io_ring_ctx
*ctx
= req
->ctx
;
5601 struct io_poll_table ipt
;
5604 ipt
.pt
._qproc
= io_poll_queue_proc
;
5606 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5609 if (mask
) { /* no async, we'd stolen it */
5611 io_poll_complete(req
, mask
, 0);
5613 spin_unlock_irq(&ctx
->completion_lock
);
5616 io_cqring_ev_posted(ctx
);
5622 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5624 struct io_timeout_data
*data
= container_of(timer
,
5625 struct io_timeout_data
, timer
);
5626 struct io_kiocb
*req
= data
->req
;
5627 struct io_ring_ctx
*ctx
= req
->ctx
;
5628 unsigned long flags
;
5630 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5631 list_del_init(&req
->timeout
.list
);
5632 atomic_set(&req
->ctx
->cq_timeouts
,
5633 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5635 io_cqring_fill_event(req
, -ETIME
);
5636 io_commit_cqring(ctx
);
5637 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5639 io_cqring_ev_posted(ctx
);
5640 req_set_fail_links(req
);
5642 return HRTIMER_NORESTART
;
5645 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5648 struct io_timeout_data
*io
;
5649 struct io_kiocb
*req
;
5652 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5653 if (user_data
== req
->user_data
) {
5660 return ERR_PTR(ret
);
5662 io
= req
->async_data
;
5663 ret
= hrtimer_try_to_cancel(&io
->timer
);
5665 return ERR_PTR(-EALREADY
);
5666 list_del_init(&req
->timeout
.list
);
5670 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5672 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5675 return PTR_ERR(req
);
5677 req_set_fail_links(req
);
5678 io_cqring_fill_event(req
, -ECANCELED
);
5679 io_put_req_deferred(req
, 1);
5683 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
5684 struct timespec64
*ts
, enum hrtimer_mode mode
)
5686 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5687 struct io_timeout_data
*data
;
5690 return PTR_ERR(req
);
5692 req
->timeout
.off
= 0; /* noseq */
5693 data
= req
->async_data
;
5694 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
5695 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, mode
);
5696 data
->timer
.function
= io_timeout_fn
;
5697 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
5701 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5702 const struct io_uring_sqe
*sqe
)
5704 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5706 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5708 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5710 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5713 tr
->addr
= READ_ONCE(sqe
->addr
);
5714 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
5715 if (tr
->flags
& IORING_TIMEOUT_UPDATE
) {
5716 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE
|IORING_TIMEOUT_ABS
))
5718 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
5720 } else if (tr
->flags
) {
5721 /* timeout removal doesn't support flags */
5729 * Remove or update an existing timeout command
5731 static int io_timeout_remove(struct io_kiocb
*req
)
5733 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5734 struct io_ring_ctx
*ctx
= req
->ctx
;
5737 spin_lock_irq(&ctx
->completion_lock
);
5738 if (req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
) {
5739 enum hrtimer_mode mode
= (tr
->flags
& IORING_TIMEOUT_ABS
)
5740 ? HRTIMER_MODE_ABS
: HRTIMER_MODE_REL
;
5742 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
, mode
);
5744 ret
= io_timeout_cancel(ctx
, tr
->addr
);
5747 io_cqring_fill_event(req
, ret
);
5748 io_commit_cqring(ctx
);
5749 spin_unlock_irq(&ctx
->completion_lock
);
5750 io_cqring_ev_posted(ctx
);
5752 req_set_fail_links(req
);
5757 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5758 bool is_timeout_link
)
5760 struct io_timeout_data
*data
;
5762 u32 off
= READ_ONCE(sqe
->off
);
5764 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5766 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5768 if (off
&& is_timeout_link
)
5770 flags
= READ_ONCE(sqe
->timeout_flags
);
5771 if (flags
& ~IORING_TIMEOUT_ABS
)
5774 req
->timeout
.off
= off
;
5776 if (!req
->async_data
&& io_alloc_async_data(req
))
5779 data
= req
->async_data
;
5782 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5785 if (flags
& IORING_TIMEOUT_ABS
)
5786 data
->mode
= HRTIMER_MODE_ABS
;
5788 data
->mode
= HRTIMER_MODE_REL
;
5790 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5794 static int io_timeout(struct io_kiocb
*req
)
5796 struct io_ring_ctx
*ctx
= req
->ctx
;
5797 struct io_timeout_data
*data
= req
->async_data
;
5798 struct list_head
*entry
;
5799 u32 tail
, off
= req
->timeout
.off
;
5801 spin_lock_irq(&ctx
->completion_lock
);
5804 * sqe->off holds how many events that need to occur for this
5805 * timeout event to be satisfied. If it isn't set, then this is
5806 * a pure timeout request, sequence isn't used.
5808 if (io_is_timeout_noseq(req
)) {
5809 entry
= ctx
->timeout_list
.prev
;
5813 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5814 req
->timeout
.target_seq
= tail
+ off
;
5817 * Insertion sort, ensuring the first entry in the list is always
5818 * the one we need first.
5820 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5821 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5824 if (io_is_timeout_noseq(nxt
))
5826 /* nxt.seq is behind @tail, otherwise would've been completed */
5827 if (off
>= nxt
->timeout
.target_seq
- tail
)
5831 list_add(&req
->timeout
.list
, entry
);
5832 data
->timer
.function
= io_timeout_fn
;
5833 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5834 spin_unlock_irq(&ctx
->completion_lock
);
5838 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5840 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5842 return req
->user_data
== (unsigned long) data
;
5845 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5847 enum io_wq_cancel cancel_ret
;
5850 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5851 switch (cancel_ret
) {
5852 case IO_WQ_CANCEL_OK
:
5855 case IO_WQ_CANCEL_RUNNING
:
5858 case IO_WQ_CANCEL_NOTFOUND
:
5866 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5867 struct io_kiocb
*req
, __u64 sqe_addr
,
5870 unsigned long flags
;
5873 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5874 if (ret
!= -ENOENT
) {
5875 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5879 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5880 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5883 ret
= io_poll_cancel(ctx
, sqe_addr
);
5887 io_cqring_fill_event(req
, ret
);
5888 io_commit_cqring(ctx
);
5889 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5890 io_cqring_ev_posted(ctx
);
5893 req_set_fail_links(req
);
5897 static int io_async_cancel_prep(struct io_kiocb
*req
,
5898 const struct io_uring_sqe
*sqe
)
5900 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5902 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5904 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5907 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5911 static int io_async_cancel(struct io_kiocb
*req
)
5913 struct io_ring_ctx
*ctx
= req
->ctx
;
5915 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
5919 static int io_files_update_prep(struct io_kiocb
*req
,
5920 const struct io_uring_sqe
*sqe
)
5922 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
5924 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5926 if (sqe
->ioprio
|| sqe
->rw_flags
)
5929 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
5930 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
5931 if (!req
->files_update
.nr_args
)
5933 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
5937 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
,
5938 struct io_comp_state
*cs
)
5940 struct io_ring_ctx
*ctx
= req
->ctx
;
5941 struct io_uring_files_update up
;
5947 up
.offset
= req
->files_update
.offset
;
5948 up
.fds
= req
->files_update
.arg
;
5950 mutex_lock(&ctx
->uring_lock
);
5951 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
5952 mutex_unlock(&ctx
->uring_lock
);
5955 req_set_fail_links(req
);
5956 __io_req_complete(req
, ret
, 0, cs
);
5960 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5962 switch (req
->opcode
) {
5965 case IORING_OP_READV
:
5966 case IORING_OP_READ_FIXED
:
5967 case IORING_OP_READ
:
5968 return io_read_prep(req
, sqe
);
5969 case IORING_OP_WRITEV
:
5970 case IORING_OP_WRITE_FIXED
:
5971 case IORING_OP_WRITE
:
5972 return io_write_prep(req
, sqe
);
5973 case IORING_OP_POLL_ADD
:
5974 return io_poll_add_prep(req
, sqe
);
5975 case IORING_OP_POLL_REMOVE
:
5976 return io_poll_remove_prep(req
, sqe
);
5977 case IORING_OP_FSYNC
:
5978 return io_prep_fsync(req
, sqe
);
5979 case IORING_OP_SYNC_FILE_RANGE
:
5980 return io_prep_sfr(req
, sqe
);
5981 case IORING_OP_SENDMSG
:
5982 case IORING_OP_SEND
:
5983 return io_sendmsg_prep(req
, sqe
);
5984 case IORING_OP_RECVMSG
:
5985 case IORING_OP_RECV
:
5986 return io_recvmsg_prep(req
, sqe
);
5987 case IORING_OP_CONNECT
:
5988 return io_connect_prep(req
, sqe
);
5989 case IORING_OP_TIMEOUT
:
5990 return io_timeout_prep(req
, sqe
, false);
5991 case IORING_OP_TIMEOUT_REMOVE
:
5992 return io_timeout_remove_prep(req
, sqe
);
5993 case IORING_OP_ASYNC_CANCEL
:
5994 return io_async_cancel_prep(req
, sqe
);
5995 case IORING_OP_LINK_TIMEOUT
:
5996 return io_timeout_prep(req
, sqe
, true);
5997 case IORING_OP_ACCEPT
:
5998 return io_accept_prep(req
, sqe
);
5999 case IORING_OP_FALLOCATE
:
6000 return io_fallocate_prep(req
, sqe
);
6001 case IORING_OP_OPENAT
:
6002 return io_openat_prep(req
, sqe
);
6003 case IORING_OP_CLOSE
:
6004 return io_close_prep(req
, sqe
);
6005 case IORING_OP_FILES_UPDATE
:
6006 return io_files_update_prep(req
, sqe
);
6007 case IORING_OP_STATX
:
6008 return io_statx_prep(req
, sqe
);
6009 case IORING_OP_FADVISE
:
6010 return io_fadvise_prep(req
, sqe
);
6011 case IORING_OP_MADVISE
:
6012 return io_madvise_prep(req
, sqe
);
6013 case IORING_OP_OPENAT2
:
6014 return io_openat2_prep(req
, sqe
);
6015 case IORING_OP_EPOLL_CTL
:
6016 return io_epoll_ctl_prep(req
, sqe
);
6017 case IORING_OP_SPLICE
:
6018 return io_splice_prep(req
, sqe
);
6019 case IORING_OP_PROVIDE_BUFFERS
:
6020 return io_provide_buffers_prep(req
, sqe
);
6021 case IORING_OP_REMOVE_BUFFERS
:
6022 return io_remove_buffers_prep(req
, sqe
);
6024 return io_tee_prep(req
, sqe
);
6025 case IORING_OP_SHUTDOWN
:
6026 return io_shutdown_prep(req
, sqe
);
6027 case IORING_OP_RENAMEAT
:
6028 return io_renameat_prep(req
, sqe
);
6029 case IORING_OP_UNLINKAT
:
6030 return io_unlinkat_prep(req
, sqe
);
6033 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
6038 static int io_req_defer_prep(struct io_kiocb
*req
,
6039 const struct io_uring_sqe
*sqe
)
6043 if (io_alloc_async_data(req
))
6045 return io_req_prep(req
, sqe
);
6048 static u32
io_get_sequence(struct io_kiocb
*req
)
6050 struct io_kiocb
*pos
;
6051 struct io_ring_ctx
*ctx
= req
->ctx
;
6052 u32 total_submitted
, nr_reqs
= 0;
6054 io_for_each_link(pos
, req
)
6057 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
6058 return total_submitted
- nr_reqs
;
6061 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6063 struct io_ring_ctx
*ctx
= req
->ctx
;
6064 struct io_defer_entry
*de
;
6068 /* Still need defer if there is pending req in defer list. */
6069 if (likely(list_empty_careful(&ctx
->defer_list
) &&
6070 !(req
->flags
& REQ_F_IO_DRAIN
)))
6073 seq
= io_get_sequence(req
);
6074 /* Still a chance to pass the sequence check */
6075 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
6078 if (!req
->async_data
) {
6079 ret
= io_req_defer_prep(req
, sqe
);
6083 io_prep_async_link(req
);
6084 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
6088 spin_lock_irq(&ctx
->completion_lock
);
6089 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
6090 spin_unlock_irq(&ctx
->completion_lock
);
6092 io_queue_async_work(req
);
6093 return -EIOCBQUEUED
;
6096 trace_io_uring_defer(ctx
, req
, req
->user_data
);
6099 list_add_tail(&de
->list
, &ctx
->defer_list
);
6100 spin_unlock_irq(&ctx
->completion_lock
);
6101 return -EIOCBQUEUED
;
6104 static void io_req_drop_files(struct io_kiocb
*req
)
6106 struct io_ring_ctx
*ctx
= req
->ctx
;
6107 struct io_uring_task
*tctx
= req
->task
->io_uring
;
6108 unsigned long flags
;
6110 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
6111 list_del(&req
->inflight_entry
);
6112 if (atomic_read(&tctx
->in_idle
))
6113 wake_up(&tctx
->wait
);
6114 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
6115 req
->flags
&= ~REQ_F_INFLIGHT
;
6116 put_files_struct(req
->work
.identity
->files
);
6117 put_nsproxy(req
->work
.identity
->nsproxy
);
6118 req
->work
.flags
&= ~IO_WQ_WORK_FILES
;
6121 static void __io_clean_op(struct io_kiocb
*req
)
6123 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6124 switch (req
->opcode
) {
6125 case IORING_OP_READV
:
6126 case IORING_OP_READ_FIXED
:
6127 case IORING_OP_READ
:
6128 kfree((void *)(unsigned long)req
->rw
.addr
);
6130 case IORING_OP_RECVMSG
:
6131 case IORING_OP_RECV
:
6132 kfree(req
->sr_msg
.kbuf
);
6135 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
6138 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6139 switch (req
->opcode
) {
6140 case IORING_OP_READV
:
6141 case IORING_OP_READ_FIXED
:
6142 case IORING_OP_READ
:
6143 case IORING_OP_WRITEV
:
6144 case IORING_OP_WRITE_FIXED
:
6145 case IORING_OP_WRITE
: {
6146 struct io_async_rw
*io
= req
->async_data
;
6148 kfree(io
->free_iovec
);
6151 case IORING_OP_RECVMSG
:
6152 case IORING_OP_SENDMSG
: {
6153 struct io_async_msghdr
*io
= req
->async_data
;
6154 if (io
->iov
!= io
->fast_iov
)
6158 case IORING_OP_SPLICE
:
6160 io_put_file(req
, req
->splice
.file_in
,
6161 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
6163 case IORING_OP_OPENAT
:
6164 case IORING_OP_OPENAT2
:
6165 if (req
->open
.filename
)
6166 putname(req
->open
.filename
);
6168 case IORING_OP_RENAMEAT
:
6169 putname(req
->rename
.oldpath
);
6170 putname(req
->rename
.newpath
);
6172 case IORING_OP_UNLINKAT
:
6173 putname(req
->unlink
.filename
);
6176 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
6179 if (req
->flags
& REQ_F_INFLIGHT
)
6180 io_req_drop_files(req
);
6183 static int io_issue_sqe(struct io_kiocb
*req
, bool force_nonblock
,
6184 struct io_comp_state
*cs
)
6186 struct io_ring_ctx
*ctx
= req
->ctx
;
6189 switch (req
->opcode
) {
6191 ret
= io_nop(req
, cs
);
6193 case IORING_OP_READV
:
6194 case IORING_OP_READ_FIXED
:
6195 case IORING_OP_READ
:
6196 ret
= io_read(req
, force_nonblock
, cs
);
6198 case IORING_OP_WRITEV
:
6199 case IORING_OP_WRITE_FIXED
:
6200 case IORING_OP_WRITE
:
6201 ret
= io_write(req
, force_nonblock
, cs
);
6203 case IORING_OP_FSYNC
:
6204 ret
= io_fsync(req
, force_nonblock
);
6206 case IORING_OP_POLL_ADD
:
6207 ret
= io_poll_add(req
);
6209 case IORING_OP_POLL_REMOVE
:
6210 ret
= io_poll_remove(req
);
6212 case IORING_OP_SYNC_FILE_RANGE
:
6213 ret
= io_sync_file_range(req
, force_nonblock
);
6215 case IORING_OP_SENDMSG
:
6216 ret
= io_sendmsg(req
, force_nonblock
, cs
);
6218 case IORING_OP_SEND
:
6219 ret
= io_send(req
, force_nonblock
, cs
);
6221 case IORING_OP_RECVMSG
:
6222 ret
= io_recvmsg(req
, force_nonblock
, cs
);
6224 case IORING_OP_RECV
:
6225 ret
= io_recv(req
, force_nonblock
, cs
);
6227 case IORING_OP_TIMEOUT
:
6228 ret
= io_timeout(req
);
6230 case IORING_OP_TIMEOUT_REMOVE
:
6231 ret
= io_timeout_remove(req
);
6233 case IORING_OP_ACCEPT
:
6234 ret
= io_accept(req
, force_nonblock
, cs
);
6236 case IORING_OP_CONNECT
:
6237 ret
= io_connect(req
, force_nonblock
, cs
);
6239 case IORING_OP_ASYNC_CANCEL
:
6240 ret
= io_async_cancel(req
);
6242 case IORING_OP_FALLOCATE
:
6243 ret
= io_fallocate(req
, force_nonblock
);
6245 case IORING_OP_OPENAT
:
6246 ret
= io_openat(req
, force_nonblock
);
6248 case IORING_OP_CLOSE
:
6249 ret
= io_close(req
, force_nonblock
, cs
);
6251 case IORING_OP_FILES_UPDATE
:
6252 ret
= io_files_update(req
, force_nonblock
, cs
);
6254 case IORING_OP_STATX
:
6255 ret
= io_statx(req
, force_nonblock
);
6257 case IORING_OP_FADVISE
:
6258 ret
= io_fadvise(req
, force_nonblock
);
6260 case IORING_OP_MADVISE
:
6261 ret
= io_madvise(req
, force_nonblock
);
6263 case IORING_OP_OPENAT2
:
6264 ret
= io_openat2(req
, force_nonblock
);
6266 case IORING_OP_EPOLL_CTL
:
6267 ret
= io_epoll_ctl(req
, force_nonblock
, cs
);
6269 case IORING_OP_SPLICE
:
6270 ret
= io_splice(req
, force_nonblock
);
6272 case IORING_OP_PROVIDE_BUFFERS
:
6273 ret
= io_provide_buffers(req
, force_nonblock
, cs
);
6275 case IORING_OP_REMOVE_BUFFERS
:
6276 ret
= io_remove_buffers(req
, force_nonblock
, cs
);
6279 ret
= io_tee(req
, force_nonblock
);
6281 case IORING_OP_SHUTDOWN
:
6282 ret
= io_shutdown(req
, force_nonblock
);
6284 case IORING_OP_RENAMEAT
:
6285 ret
= io_renameat(req
, force_nonblock
);
6287 case IORING_OP_UNLINKAT
:
6288 ret
= io_unlinkat(req
, force_nonblock
);
6298 /* If the op doesn't have a file, we're not polling for it */
6299 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
6300 const bool in_async
= io_wq_current_is_worker();
6302 /* workqueue context doesn't hold uring_lock, grab it now */
6304 mutex_lock(&ctx
->uring_lock
);
6306 io_iopoll_req_issued(req
, in_async
);
6309 mutex_unlock(&ctx
->uring_lock
);
6315 static struct io_wq_work
*io_wq_submit_work(struct io_wq_work
*work
)
6317 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6318 struct io_kiocb
*timeout
;
6321 timeout
= io_prep_linked_timeout(req
);
6323 io_queue_linked_timeout(timeout
);
6325 /* if NO_CANCEL is set, we must still run the work */
6326 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
6327 IO_WQ_WORK_CANCEL
) {
6333 ret
= io_issue_sqe(req
, false, NULL
);
6335 * We can get EAGAIN for polled IO even though we're
6336 * forcing a sync submission from here, since we can't
6337 * wait for request slots on the block side.
6347 * io_iopoll_complete() does not hold completion_lock to complete
6348 * polled io, so here for polled io, just mark it done and still let
6349 * io_iopoll_complete() complete it.
6351 if (req
->ctx
->flags
& IORING_SETUP_IOPOLL
) {
6352 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
6354 kiocb_done(kiocb
, ret
, NULL
);
6356 req_set_fail_links(req
);
6357 io_req_complete(req
, ret
);
6361 return io_steal_work(req
);
6364 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6367 struct fixed_file_table
*table
;
6369 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
6370 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
6373 static struct file
*io_file_get(struct io_submit_state
*state
,
6374 struct io_kiocb
*req
, int fd
, bool fixed
)
6376 struct io_ring_ctx
*ctx
= req
->ctx
;
6380 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6382 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6383 file
= io_file_from_index(ctx
, fd
);
6384 io_set_resource_node(req
);
6386 trace_io_uring_file_get(ctx
, fd
);
6387 file
= __io_file_get(state
, fd
);
6393 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6395 struct io_timeout_data
*data
= container_of(timer
,
6396 struct io_timeout_data
, timer
);
6397 struct io_kiocb
*prev
, *req
= data
->req
;
6398 struct io_ring_ctx
*ctx
= req
->ctx
;
6399 unsigned long flags
;
6401 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6402 prev
= req
->timeout
.head
;
6403 req
->timeout
.head
= NULL
;
6406 * We don't expect the list to be empty, that will only happen if we
6407 * race with the completion of the linked work.
6409 if (prev
&& refcount_inc_not_zero(&prev
->refs
))
6410 io_remove_next_linked(prev
);
6413 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6416 req_set_fail_links(prev
);
6417 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6420 io_req_complete(req
, -ETIME
);
6422 return HRTIMER_NORESTART
;
6425 static void __io_queue_linked_timeout(struct io_kiocb
*req
)
6428 * If the back reference is NULL, then our linked request finished
6429 * before we got a chance to setup the timer
6431 if (req
->timeout
.head
) {
6432 struct io_timeout_data
*data
= req
->async_data
;
6434 data
->timer
.function
= io_link_timeout_fn
;
6435 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6440 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6442 struct io_ring_ctx
*ctx
= req
->ctx
;
6444 spin_lock_irq(&ctx
->completion_lock
);
6445 __io_queue_linked_timeout(req
);
6446 spin_unlock_irq(&ctx
->completion_lock
);
6448 /* drop submission reference */
6452 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6454 struct io_kiocb
*nxt
= req
->link
;
6456 if (!nxt
|| (req
->flags
& REQ_F_LINK_TIMEOUT
) ||
6457 nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6460 nxt
->timeout
.head
= req
;
6461 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6462 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6466 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
)
6468 struct io_kiocb
*linked_timeout
;
6469 const struct cred
*old_creds
= NULL
;
6473 linked_timeout
= io_prep_linked_timeout(req
);
6475 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
6476 (req
->work
.flags
& IO_WQ_WORK_CREDS
) &&
6477 req
->work
.identity
->creds
!= current_cred()) {
6479 revert_creds(old_creds
);
6480 if (old_creds
== req
->work
.identity
->creds
)
6481 old_creds
= NULL
; /* restored original creds */
6483 old_creds
= override_creds(req
->work
.identity
->creds
);
6486 ret
= io_issue_sqe(req
, true, cs
);
6489 * We async punt it if the file wasn't marked NOWAIT, or if the file
6490 * doesn't support non-blocking read/write attempts
6492 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6493 if (!io_arm_poll_handler(req
)) {
6495 * Queued up for async execution, worker will release
6496 * submit reference when the iocb is actually submitted.
6498 io_queue_async_work(req
);
6502 io_queue_linked_timeout(linked_timeout
);
6503 } else if (likely(!ret
)) {
6504 /* drop submission reference */
6505 req
= io_put_req_find_next(req
);
6507 io_queue_linked_timeout(linked_timeout
);
6510 if (!(req
->flags
& REQ_F_FORCE_ASYNC
))
6512 io_queue_async_work(req
);
6515 /* un-prep timeout, so it'll be killed as any other linked */
6516 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6517 req_set_fail_links(req
);
6519 io_req_complete(req
, ret
);
6523 revert_creds(old_creds
);
6526 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6527 struct io_comp_state
*cs
)
6531 ret
= io_req_defer(req
, sqe
);
6533 if (ret
!= -EIOCBQUEUED
) {
6535 req_set_fail_links(req
);
6537 io_req_complete(req
, ret
);
6539 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6540 if (!req
->async_data
) {
6541 ret
= io_req_defer_prep(req
, sqe
);
6545 io_queue_async_work(req
);
6548 ret
= io_req_prep(req
, sqe
);
6552 __io_queue_sqe(req
, cs
);
6556 static inline void io_queue_link_head(struct io_kiocb
*req
,
6557 struct io_comp_state
*cs
)
6559 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6561 io_req_complete(req
, -ECANCELED
);
6563 io_queue_sqe(req
, NULL
, cs
);
6566 struct io_submit_link
{
6567 struct io_kiocb
*head
;
6568 struct io_kiocb
*last
;
6571 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6572 struct io_submit_link
*link
, struct io_comp_state
*cs
)
6574 struct io_ring_ctx
*ctx
= req
->ctx
;
6578 * If we already have a head request, queue this one for async
6579 * submittal once the head completes. If we don't have a head but
6580 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6581 * submitted sync once the chain is complete. If none of those
6582 * conditions are true (normal request), then just queue it.
6585 struct io_kiocb
*head
= link
->head
;
6588 * Taking sequential execution of a link, draining both sides
6589 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6590 * requests in the link. So, it drains the head and the
6591 * next after the link request. The last one is done via
6592 * drain_next flag to persist the effect across calls.
6594 if (req
->flags
& REQ_F_IO_DRAIN
) {
6595 head
->flags
|= REQ_F_IO_DRAIN
;
6596 ctx
->drain_next
= 1;
6598 ret
= io_req_defer_prep(req
, sqe
);
6599 if (unlikely(ret
)) {
6600 /* fail even hard links since we don't submit */
6601 head
->flags
|= REQ_F_FAIL_LINK
;
6604 trace_io_uring_link(ctx
, req
, head
);
6605 link
->last
->link
= req
;
6608 /* last request of a link, enqueue the link */
6609 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6610 io_queue_link_head(head
, cs
);
6614 if (unlikely(ctx
->drain_next
)) {
6615 req
->flags
|= REQ_F_IO_DRAIN
;
6616 ctx
->drain_next
= 0;
6618 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6619 ret
= io_req_defer_prep(req
, sqe
);
6621 req
->flags
|= REQ_F_FAIL_LINK
;
6625 io_queue_sqe(req
, sqe
, cs
);
6633 * Batched submission is done, ensure local IO is flushed out.
6635 static void io_submit_state_end(struct io_submit_state
*state
)
6637 if (!list_empty(&state
->comp
.list
))
6638 io_submit_flush_completions(&state
->comp
);
6639 if (state
->plug_started
)
6640 blk_finish_plug(&state
->plug
);
6641 io_state_file_put(state
);
6642 if (state
->free_reqs
)
6643 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
6647 * Start submission side cache.
6649 static void io_submit_state_start(struct io_submit_state
*state
,
6650 struct io_ring_ctx
*ctx
, unsigned int max_ios
)
6652 state
->plug_started
= false;
6654 INIT_LIST_HEAD(&state
->comp
.list
);
6655 state
->comp
.ctx
= ctx
;
6656 state
->free_reqs
= 0;
6657 state
->file_refs
= 0;
6658 state
->ios_left
= max_ios
;
6661 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6663 struct io_rings
*rings
= ctx
->rings
;
6666 * Ensure any loads from the SQEs are done at this point,
6667 * since once we write the new head, the application could
6668 * write new data to them.
6670 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6674 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6675 * that is mapped by userspace. This means that care needs to be taken to
6676 * ensure that reads are stable, as we cannot rely on userspace always
6677 * being a good citizen. If members of the sqe are validated and then later
6678 * used, it's important that those reads are done through READ_ONCE() to
6679 * prevent a re-load down the line.
6681 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6683 u32
*sq_array
= ctx
->sq_array
;
6687 * The cached sq head (or cq tail) serves two purposes:
6689 * 1) allows us to batch the cost of updating the user visible
6691 * 2) allows the kernel side to track the head on its own, even
6692 * though the application is the one updating it.
6694 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
6695 if (likely(head
< ctx
->sq_entries
))
6696 return &ctx
->sq_sqes
[head
];
6698 /* drop invalid entries */
6699 ctx
->cached_sq_dropped
++;
6700 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6704 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
6706 ctx
->cached_sq_head
++;
6710 * Check SQE restrictions (opcode and flags).
6712 * Returns 'true' if SQE is allowed, 'false' otherwise.
6714 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6715 struct io_kiocb
*req
,
6716 unsigned int sqe_flags
)
6718 if (!ctx
->restricted
)
6721 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6724 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6725 ctx
->restrictions
.sqe_flags_required
)
6728 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6729 ctx
->restrictions
.sqe_flags_required
))
6735 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6736 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6737 IOSQE_BUFFER_SELECT)
6739 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6740 const struct io_uring_sqe
*sqe
,
6741 struct io_submit_state
*state
)
6743 unsigned int sqe_flags
;
6746 req
->opcode
= READ_ONCE(sqe
->opcode
);
6747 req
->user_data
= READ_ONCE(sqe
->user_data
);
6748 req
->async_data
= NULL
;
6753 req
->fixed_file_refs
= NULL
;
6754 /* one is dropped after submission, the other at completion */
6755 refcount_set(&req
->refs
, 2);
6756 req
->task
= current
;
6759 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6762 if (unlikely(io_sq_thread_acquire_mm_files(ctx
, req
)))
6765 sqe_flags
= READ_ONCE(sqe
->flags
);
6766 /* enforce forwards compatibility on users */
6767 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6770 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6773 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6774 !io_op_defs
[req
->opcode
].buffer_select
)
6777 id
= READ_ONCE(sqe
->personality
);
6779 struct io_identity
*iod
;
6781 iod
= idr_find(&ctx
->personality_idr
, id
);
6784 refcount_inc(&iod
->count
);
6786 __io_req_init_async(req
);
6787 get_cred(iod
->creds
);
6788 req
->work
.identity
= iod
;
6789 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
6792 /* same numerical values with corresponding REQ_F_*, safe to copy */
6793 req
->flags
|= sqe_flags
;
6796 * Plug now if we have more than 1 IO left after this, and the target
6797 * is potentially a read/write to block based storage.
6799 if (!state
->plug_started
&& state
->ios_left
> 1 &&
6800 io_op_defs
[req
->opcode
].plug
) {
6801 blk_start_plug(&state
->plug
);
6802 state
->plug_started
= true;
6806 if (io_op_defs
[req
->opcode
].needs_file
) {
6807 bool fixed
= req
->flags
& REQ_F_FIXED_FILE
;
6809 req
->file
= io_file_get(state
, req
, READ_ONCE(sqe
->fd
), fixed
);
6810 if (unlikely(!req
->file
&&
6811 !io_op_defs
[req
->opcode
].needs_file_no_error
))
6819 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6821 struct io_submit_state state
;
6822 struct io_submit_link link
;
6823 int i
, submitted
= 0;
6825 /* if we have a backlog and couldn't flush it all, return BUSY */
6826 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6827 if (!list_empty(&ctx
->cq_overflow_list
) &&
6828 !io_cqring_overflow_flush(ctx
, false, NULL
, NULL
))
6832 /* make sure SQ entry isn't read before tail */
6833 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6835 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6838 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6839 refcount_add(nr
, ¤t
->usage
);
6841 io_submit_state_start(&state
, ctx
, nr
);
6844 for (i
= 0; i
< nr
; i
++) {
6845 const struct io_uring_sqe
*sqe
;
6846 struct io_kiocb
*req
;
6849 sqe
= io_get_sqe(ctx
);
6850 if (unlikely(!sqe
)) {
6851 io_consume_sqe(ctx
);
6854 req
= io_alloc_req(ctx
, &state
);
6855 if (unlikely(!req
)) {
6857 submitted
= -EAGAIN
;
6860 io_consume_sqe(ctx
);
6861 /* will complete beyond this point, count as submitted */
6864 err
= io_init_req(ctx
, req
, sqe
, &state
);
6865 if (unlikely(err
)) {
6868 io_req_complete(req
, err
);
6872 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6873 true, io_async_submit(ctx
));
6874 err
= io_submit_sqe(req
, sqe
, &link
, &state
.comp
);
6879 if (unlikely(submitted
!= nr
)) {
6880 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6881 struct io_uring_task
*tctx
= current
->io_uring
;
6882 int unused
= nr
- ref_used
;
6884 percpu_ref_put_many(&ctx
->refs
, unused
);
6885 percpu_counter_sub(&tctx
->inflight
, unused
);
6886 put_task_struct_many(current
, unused
);
6889 io_queue_link_head(link
.head
, &state
.comp
);
6890 io_submit_state_end(&state
);
6892 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6893 io_commit_sqring(ctx
);
6898 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6900 /* Tell userspace we may need a wakeup call */
6901 spin_lock_irq(&ctx
->completion_lock
);
6902 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6903 spin_unlock_irq(&ctx
->completion_lock
);
6906 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6908 spin_lock_irq(&ctx
->completion_lock
);
6909 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6910 spin_unlock_irq(&ctx
->completion_lock
);
6913 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
6915 unsigned int to_submit
;
6918 to_submit
= io_sqring_entries(ctx
);
6919 /* if we're handling multiple rings, cap submit size for fairness */
6920 if (cap_entries
&& to_submit
> 8)
6923 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
6924 unsigned nr_events
= 0;
6926 mutex_lock(&ctx
->uring_lock
);
6927 if (!list_empty(&ctx
->iopoll_list
))
6928 io_do_iopoll(ctx
, &nr_events
, 0);
6930 if (to_submit
&& likely(!percpu_ref_is_dying(&ctx
->refs
)))
6931 ret
= io_submit_sqes(ctx
, to_submit
);
6932 mutex_unlock(&ctx
->uring_lock
);
6935 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
6936 wake_up(&ctx
->sqo_sq_wait
);
6941 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
6943 struct io_ring_ctx
*ctx
;
6944 unsigned sq_thread_idle
= 0;
6946 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6947 if (sq_thread_idle
< ctx
->sq_thread_idle
)
6948 sq_thread_idle
= ctx
->sq_thread_idle
;
6951 sqd
->sq_thread_idle
= sq_thread_idle
;
6954 static void io_sqd_init_new(struct io_sq_data
*sqd
)
6956 struct io_ring_ctx
*ctx
;
6958 while (!list_empty(&sqd
->ctx_new_list
)) {
6959 ctx
= list_first_entry(&sqd
->ctx_new_list
, struct io_ring_ctx
, sqd_list
);
6960 list_move_tail(&ctx
->sqd_list
, &sqd
->ctx_list
);
6961 complete(&ctx
->sq_thread_comp
);
6964 io_sqd_update_thread_idle(sqd
);
6967 static int io_sq_thread(void *data
)
6969 struct cgroup_subsys_state
*cur_css
= NULL
;
6970 struct files_struct
*old_files
= current
->files
;
6971 struct nsproxy
*old_nsproxy
= current
->nsproxy
;
6972 const struct cred
*old_cred
= NULL
;
6973 struct io_sq_data
*sqd
= data
;
6974 struct io_ring_ctx
*ctx
;
6975 unsigned long timeout
= 0;
6979 current
->files
= NULL
;
6980 current
->nsproxy
= NULL
;
6981 task_unlock(current
);
6983 while (!kthread_should_stop()) {
6985 bool cap_entries
, sqt_spin
, needs_sched
;
6988 * Any changes to the sqd lists are synchronized through the
6989 * kthread parking. This synchronizes the thread vs users,
6990 * the users are synchronized on the sqd->ctx_lock.
6992 if (kthread_should_park()) {
6995 * When sq thread is unparked, in case the previous park operation
6996 * comes from io_put_sq_data(), which means that sq thread is going
6997 * to be stopped, so here needs to have a check.
6999 if (kthread_should_stop())
7003 if (unlikely(!list_empty(&sqd
->ctx_new_list
))) {
7004 io_sqd_init_new(sqd
);
7005 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7009 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
7010 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7011 if (current
->cred
!= ctx
->creds
) {
7013 revert_creds(old_cred
);
7014 old_cred
= override_creds(ctx
->creds
);
7016 io_sq_thread_associate_blkcg(ctx
, &cur_css
);
7018 current
->loginuid
= ctx
->loginuid
;
7019 current
->sessionid
= ctx
->sessionid
;
7022 ret
= __io_sq_thread(ctx
, cap_entries
);
7023 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
7026 io_sq_thread_drop_mm_files();
7029 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
7033 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7037 if (kthread_should_park())
7041 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
7042 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7043 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
7044 !list_empty_careful(&ctx
->iopoll_list
)) {
7045 needs_sched
= false;
7048 if (io_sqring_entries(ctx
)) {
7049 needs_sched
= false;
7055 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7056 io_ring_set_wakeup_flag(ctx
);
7059 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7060 io_ring_clear_wakeup_flag(ctx
);
7063 finish_wait(&sqd
->wait
, &wait
);
7064 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7070 io_sq_thread_unassociate_blkcg();
7072 revert_creds(old_cred
);
7075 current
->files
= old_files
;
7076 current
->nsproxy
= old_nsproxy
;
7077 task_unlock(current
);
7084 struct io_wait_queue
{
7085 struct wait_queue_entry wq
;
7086 struct io_ring_ctx
*ctx
;
7088 unsigned nr_timeouts
;
7091 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
7093 struct io_ring_ctx
*ctx
= iowq
->ctx
;
7096 * Wake up if we have enough events, or if a timeout occurred since we
7097 * started waiting. For timeouts, we always want to return to userspace,
7098 * regardless of event count.
7100 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
7101 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
7104 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
7105 int wake_flags
, void *key
)
7107 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
7110 /* use noflush == true, as we can't safely rely on locking context */
7111 if (!io_should_wake(iowq
, true))
7114 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
7117 static int io_run_task_work_sig(void)
7119 if (io_run_task_work())
7121 if (!signal_pending(current
))
7123 if (test_tsk_thread_flag(current
, TIF_NOTIFY_SIGNAL
))
7124 return -ERESTARTSYS
;
7129 * Wait until events become available, if we don't already have some. The
7130 * application must reap them itself, as they reside on the shared cq ring.
7132 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
7133 const sigset_t __user
*sig
, size_t sigsz
,
7134 struct __kernel_timespec __user
*uts
)
7136 struct io_wait_queue iowq
= {
7139 .func
= io_wake_function
,
7140 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
7143 .to_wait
= min_events
,
7145 struct io_rings
*rings
= ctx
->rings
;
7146 struct timespec64 ts
;
7147 signed long timeout
= 0;
7151 if (io_cqring_events(ctx
, false) >= min_events
)
7153 if (!io_run_task_work())
7158 #ifdef CONFIG_COMPAT
7159 if (in_compat_syscall())
7160 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
7164 ret
= set_user_sigmask(sig
, sigsz
);
7171 if (get_timespec64(&ts
, uts
))
7173 timeout
= timespec64_to_jiffies(&ts
);
7176 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
7177 trace_io_uring_cqring_wait(ctx
, min_events
);
7179 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
7180 TASK_INTERRUPTIBLE
);
7181 /* make sure we run task_work before checking for signals */
7182 ret
= io_run_task_work_sig();
7187 if (io_should_wake(&iowq
, false))
7190 timeout
= schedule_timeout(timeout
);
7199 finish_wait(&ctx
->wait
, &iowq
.wq
);
7201 restore_saved_sigmask_unless(ret
== -EINTR
);
7203 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7206 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7208 #if defined(CONFIG_UNIX)
7209 if (ctx
->ring_sock
) {
7210 struct sock
*sock
= ctx
->ring_sock
->sk
;
7211 struct sk_buff
*skb
;
7213 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7219 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7222 file
= io_file_from_index(ctx
, i
);
7229 static void io_file_ref_kill(struct percpu_ref
*ref
)
7231 struct fixed_file_data
*data
;
7233 data
= container_of(ref
, struct fixed_file_data
, refs
);
7234 complete(&data
->done
);
7237 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7239 struct fixed_file_data
*data
= ctx
->file_data
;
7240 struct fixed_file_ref_node
*ref_node
= NULL
;
7241 unsigned nr_tables
, i
;
7246 spin_lock_bh(&data
->lock
);
7247 ref_node
= data
->node
;
7248 spin_unlock_bh(&data
->lock
);
7250 percpu_ref_kill(&ref_node
->refs
);
7252 percpu_ref_kill(&data
->refs
);
7254 /* wait for all refs nodes to complete */
7255 flush_delayed_work(&ctx
->file_put_work
);
7256 wait_for_completion(&data
->done
);
7258 __io_sqe_files_unregister(ctx
);
7259 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
7260 for (i
= 0; i
< nr_tables
; i
++)
7261 kfree(data
->table
[i
].files
);
7263 percpu_ref_exit(&data
->refs
);
7265 ctx
->file_data
= NULL
;
7266 ctx
->nr_user_files
= 0;
7270 static void io_put_sq_data(struct io_sq_data
*sqd
)
7272 if (refcount_dec_and_test(&sqd
->refs
)) {
7274 * The park is a bit of a work-around, without it we get
7275 * warning spews on shutdown with SQPOLL set and affinity
7276 * set to a single CPU.
7279 kthread_park(sqd
->thread
);
7280 kthread_stop(sqd
->thread
);
7287 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7289 struct io_ring_ctx
*ctx_attach
;
7290 struct io_sq_data
*sqd
;
7293 f
= fdget(p
->wq_fd
);
7295 return ERR_PTR(-ENXIO
);
7296 if (f
.file
->f_op
!= &io_uring_fops
) {
7298 return ERR_PTR(-EINVAL
);
7301 ctx_attach
= f
.file
->private_data
;
7302 sqd
= ctx_attach
->sq_data
;
7305 return ERR_PTR(-EINVAL
);
7308 refcount_inc(&sqd
->refs
);
7313 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
)
7315 struct io_sq_data
*sqd
;
7317 if (p
->flags
& IORING_SETUP_ATTACH_WQ
)
7318 return io_attach_sq_data(p
);
7320 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7322 return ERR_PTR(-ENOMEM
);
7324 refcount_set(&sqd
->refs
, 1);
7325 INIT_LIST_HEAD(&sqd
->ctx_list
);
7326 INIT_LIST_HEAD(&sqd
->ctx_new_list
);
7327 mutex_init(&sqd
->ctx_lock
);
7328 mutex_init(&sqd
->lock
);
7329 init_waitqueue_head(&sqd
->wait
);
7333 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7334 __releases(&sqd
->lock
)
7338 kthread_unpark(sqd
->thread
);
7339 mutex_unlock(&sqd
->lock
);
7342 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7343 __acquires(&sqd
->lock
)
7347 mutex_lock(&sqd
->lock
);
7348 kthread_park(sqd
->thread
);
7351 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
7353 struct io_sq_data
*sqd
= ctx
->sq_data
;
7358 * We may arrive here from the error branch in
7359 * io_sq_offload_create() where the kthread is created
7360 * without being waked up, thus wake it up now to make
7361 * sure the wait will complete.
7363 wake_up_process(sqd
->thread
);
7364 wait_for_completion(&ctx
->sq_thread_comp
);
7366 io_sq_thread_park(sqd
);
7369 mutex_lock(&sqd
->ctx_lock
);
7370 list_del(&ctx
->sqd_list
);
7371 io_sqd_update_thread_idle(sqd
);
7372 mutex_unlock(&sqd
->ctx_lock
);
7375 io_sq_thread_unpark(sqd
);
7377 io_put_sq_data(sqd
);
7378 ctx
->sq_data
= NULL
;
7382 static void io_finish_async(struct io_ring_ctx
*ctx
)
7384 io_sq_thread_stop(ctx
);
7387 io_wq_destroy(ctx
->io_wq
);
7392 #if defined(CONFIG_UNIX)
7394 * Ensure the UNIX gc is aware of our file set, so we are certain that
7395 * the io_uring can be safely unregistered on process exit, even if we have
7396 * loops in the file referencing.
7398 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7400 struct sock
*sk
= ctx
->ring_sock
->sk
;
7401 struct scm_fp_list
*fpl
;
7402 struct sk_buff
*skb
;
7405 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7409 skb
= alloc_skb(0, GFP_KERNEL
);
7418 fpl
->user
= get_uid(ctx
->user
);
7419 for (i
= 0; i
< nr
; i
++) {
7420 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7424 fpl
->fp
[nr_files
] = get_file(file
);
7425 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7430 fpl
->max
= SCM_MAX_FD
;
7431 fpl
->count
= nr_files
;
7432 UNIXCB(skb
).fp
= fpl
;
7433 skb
->destructor
= unix_destruct_scm
;
7434 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7435 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7437 for (i
= 0; i
< nr_files
; i
++)
7448 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7449 * causes regular reference counting to break down. We rely on the UNIX
7450 * garbage collection to take care of this problem for us.
7452 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7454 unsigned left
, total
;
7458 left
= ctx
->nr_user_files
;
7460 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7462 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7466 total
+= this_files
;
7472 while (total
< ctx
->nr_user_files
) {
7473 struct file
*file
= io_file_from_index(ctx
, total
);
7483 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7489 static int io_sqe_alloc_file_tables(struct fixed_file_data
*file_data
,
7490 unsigned nr_tables
, unsigned nr_files
)
7494 for (i
= 0; i
< nr_tables
; i
++) {
7495 struct fixed_file_table
*table
= &file_data
->table
[i
];
7496 unsigned this_files
;
7498 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7499 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
7503 nr_files
-= this_files
;
7509 for (i
= 0; i
< nr_tables
; i
++) {
7510 struct fixed_file_table
*table
= &file_data
->table
[i
];
7511 kfree(table
->files
);
7516 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
7518 #if defined(CONFIG_UNIX)
7519 struct sock
*sock
= ctx
->ring_sock
->sk
;
7520 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7521 struct sk_buff
*skb
;
7524 __skb_queue_head_init(&list
);
7527 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7528 * remove this entry and rearrange the file array.
7530 skb
= skb_dequeue(head
);
7532 struct scm_fp_list
*fp
;
7534 fp
= UNIXCB(skb
).fp
;
7535 for (i
= 0; i
< fp
->count
; i
++) {
7538 if (fp
->fp
[i
] != file
)
7541 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7542 left
= fp
->count
- 1 - i
;
7544 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7545 left
* sizeof(struct file
*));
7552 __skb_queue_tail(&list
, skb
);
7562 __skb_queue_tail(&list
, skb
);
7564 skb
= skb_dequeue(head
);
7567 if (skb_peek(&list
)) {
7568 spin_lock_irq(&head
->lock
);
7569 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7570 __skb_queue_tail(head
, skb
);
7571 spin_unlock_irq(&head
->lock
);
7578 struct io_file_put
{
7579 struct list_head list
;
7583 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
7585 struct fixed_file_data
*file_data
= ref_node
->file_data
;
7586 struct io_ring_ctx
*ctx
= file_data
->ctx
;
7587 struct io_file_put
*pfile
, *tmp
;
7589 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
7590 list_del(&pfile
->list
);
7591 io_ring_file_put(ctx
, pfile
->file
);
7595 percpu_ref_exit(&ref_node
->refs
);
7597 percpu_ref_put(&file_data
->refs
);
7600 static void io_file_put_work(struct work_struct
*work
)
7602 struct io_ring_ctx
*ctx
;
7603 struct llist_node
*node
;
7605 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
7606 node
= llist_del_all(&ctx
->file_put_llist
);
7609 struct fixed_file_ref_node
*ref_node
;
7610 struct llist_node
*next
= node
->next
;
7612 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
7613 __io_file_put_work(ref_node
);
7618 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
7620 struct fixed_file_ref_node
*ref_node
;
7621 struct fixed_file_data
*data
;
7622 struct io_ring_ctx
*ctx
;
7623 bool first_add
= false;
7626 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
7627 data
= ref_node
->file_data
;
7630 spin_lock_bh(&data
->lock
);
7631 ref_node
->done
= true;
7633 while (!list_empty(&data
->ref_list
)) {
7634 ref_node
= list_first_entry(&data
->ref_list
,
7635 struct fixed_file_ref_node
, node
);
7636 /* recycle ref nodes in order */
7637 if (!ref_node
->done
)
7639 list_del(&ref_node
->node
);
7640 first_add
|= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
7642 spin_unlock_bh(&data
->lock
);
7644 if (percpu_ref_is_dying(&data
->refs
))
7648 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
7650 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
7653 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
7654 struct io_ring_ctx
*ctx
)
7656 struct fixed_file_ref_node
*ref_node
;
7658 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7660 return ERR_PTR(-ENOMEM
);
7662 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
7665 return ERR_PTR(-ENOMEM
);
7667 INIT_LIST_HEAD(&ref_node
->node
);
7668 INIT_LIST_HEAD(&ref_node
->file_list
);
7669 ref_node
->file_data
= ctx
->file_data
;
7670 ref_node
->done
= false;
7674 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
7676 percpu_ref_exit(&ref_node
->refs
);
7680 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7683 __s32 __user
*fds
= (__s32 __user
*) arg
;
7684 unsigned nr_tables
, i
;
7686 int fd
, ret
= -ENOMEM
;
7687 struct fixed_file_ref_node
*ref_node
;
7688 struct fixed_file_data
*file_data
;
7694 if (nr_args
> IORING_MAX_FIXED_FILES
)
7697 file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
7700 file_data
->ctx
= ctx
;
7701 init_completion(&file_data
->done
);
7702 INIT_LIST_HEAD(&file_data
->ref_list
);
7703 spin_lock_init(&file_data
->lock
);
7705 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7706 file_data
->table
= kcalloc(nr_tables
, sizeof(*file_data
->table
),
7708 if (!file_data
->table
)
7711 if (percpu_ref_init(&file_data
->refs
, io_file_ref_kill
,
7712 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
7715 if (io_sqe_alloc_file_tables(file_data
, nr_tables
, nr_args
))
7717 ctx
->file_data
= file_data
;
7719 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7720 struct fixed_file_table
*table
;
7723 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7727 /* allow sparse sets */
7737 * Don't allow io_uring instances to be registered. If UNIX
7738 * isn't enabled, then this causes a reference cycle and this
7739 * instance can never get freed. If UNIX is enabled we'll
7740 * handle it just fine, but there's still no point in allowing
7741 * a ring fd as it doesn't support regular read/write anyway.
7743 if (file
->f_op
== &io_uring_fops
) {
7747 table
= &file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7748 index
= i
& IORING_FILE_TABLE_MASK
;
7749 table
->files
[index
] = file
;
7752 ret
= io_sqe_files_scm(ctx
);
7754 io_sqe_files_unregister(ctx
);
7758 ref_node
= alloc_fixed_file_ref_node(ctx
);
7759 if (IS_ERR(ref_node
)) {
7760 io_sqe_files_unregister(ctx
);
7761 return PTR_ERR(ref_node
);
7764 file_data
->node
= ref_node
;
7765 spin_lock_bh(&file_data
->lock
);
7766 list_add_tail(&ref_node
->node
, &file_data
->ref_list
);
7767 spin_unlock_bh(&file_data
->lock
);
7768 percpu_ref_get(&file_data
->refs
);
7771 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7772 file
= io_file_from_index(ctx
, i
);
7776 for (i
= 0; i
< nr_tables
; i
++)
7777 kfree(file_data
->table
[i
].files
);
7778 ctx
->nr_user_files
= 0;
7780 percpu_ref_exit(&file_data
->refs
);
7782 kfree(file_data
->table
);
7784 ctx
->file_data
= NULL
;
7788 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7791 #if defined(CONFIG_UNIX)
7792 struct sock
*sock
= ctx
->ring_sock
->sk
;
7793 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7794 struct sk_buff
*skb
;
7797 * See if we can merge this file into an existing skb SCM_RIGHTS
7798 * file set. If there's no room, fall back to allocating a new skb
7799 * and filling it in.
7801 spin_lock_irq(&head
->lock
);
7802 skb
= skb_peek(head
);
7804 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7806 if (fpl
->count
< SCM_MAX_FD
) {
7807 __skb_unlink(skb
, head
);
7808 spin_unlock_irq(&head
->lock
);
7809 fpl
->fp
[fpl
->count
] = get_file(file
);
7810 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7812 spin_lock_irq(&head
->lock
);
7813 __skb_queue_head(head
, skb
);
7818 spin_unlock_irq(&head
->lock
);
7825 return __io_sqe_files_scm(ctx
, 1, index
);
7831 static int io_queue_file_removal(struct fixed_file_data
*data
,
7834 struct io_file_put
*pfile
;
7835 struct fixed_file_ref_node
*ref_node
= data
->node
;
7837 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
7842 list_add(&pfile
->list
, &ref_node
->file_list
);
7847 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7848 struct io_uring_files_update
*up
,
7851 struct fixed_file_data
*data
= ctx
->file_data
;
7852 struct fixed_file_ref_node
*ref_node
;
7857 bool needs_switch
= false;
7859 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7861 if (done
> ctx
->nr_user_files
)
7864 ref_node
= alloc_fixed_file_ref_node(ctx
);
7865 if (IS_ERR(ref_node
))
7866 return PTR_ERR(ref_node
);
7869 fds
= u64_to_user_ptr(up
->fds
);
7871 struct fixed_file_table
*table
;
7875 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7879 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
7880 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7881 index
= i
& IORING_FILE_TABLE_MASK
;
7882 if (table
->files
[index
]) {
7883 file
= table
->files
[index
];
7884 err
= io_queue_file_removal(data
, file
);
7887 table
->files
[index
] = NULL
;
7888 needs_switch
= true;
7897 * Don't allow io_uring instances to be registered. If
7898 * UNIX isn't enabled, then this causes a reference
7899 * cycle and this instance can never get freed. If UNIX
7900 * is enabled we'll handle it just fine, but there's
7901 * still no point in allowing a ring fd as it doesn't
7902 * support regular read/write anyway.
7904 if (file
->f_op
== &io_uring_fops
) {
7909 table
->files
[index
] = file
;
7910 err
= io_sqe_file_register(ctx
, file
, i
);
7912 table
->files
[index
] = NULL
;
7923 percpu_ref_kill(&data
->node
->refs
);
7924 spin_lock_bh(&data
->lock
);
7925 list_add_tail(&ref_node
->node
, &data
->ref_list
);
7926 data
->node
= ref_node
;
7927 spin_unlock_bh(&data
->lock
);
7928 percpu_ref_get(&ctx
->file_data
->refs
);
7930 destroy_fixed_file_ref_node(ref_node
);
7932 return done
? done
: err
;
7935 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7938 struct io_uring_files_update up
;
7940 if (!ctx
->file_data
)
7944 if (copy_from_user(&up
, arg
, sizeof(up
)))
7949 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7952 static void io_free_work(struct io_wq_work
*work
)
7954 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7956 /* Consider that io_steal_work() relies on this ref */
7960 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
7961 struct io_uring_params
*p
)
7963 struct io_wq_data data
;
7965 struct io_ring_ctx
*ctx_attach
;
7966 unsigned int concurrency
;
7969 data
.user
= ctx
->user
;
7970 data
.free_work
= io_free_work
;
7971 data
.do_work
= io_wq_submit_work
;
7973 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
7974 /* Do QD, or 4 * CPUS, whatever is smallest */
7975 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7977 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
7978 if (IS_ERR(ctx
->io_wq
)) {
7979 ret
= PTR_ERR(ctx
->io_wq
);
7985 f
= fdget(p
->wq_fd
);
7989 if (f
.file
->f_op
!= &io_uring_fops
) {
7994 ctx_attach
= f
.file
->private_data
;
7995 /* @io_wq is protected by holding the fd */
7996 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
8001 ctx
->io_wq
= ctx_attach
->io_wq
;
8007 static int io_uring_alloc_task_context(struct task_struct
*task
)
8009 struct io_uring_task
*tctx
;
8012 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
8013 if (unlikely(!tctx
))
8016 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
8017 if (unlikely(ret
)) {
8023 init_waitqueue_head(&tctx
->wait
);
8025 atomic_set(&tctx
->in_idle
, 0);
8026 tctx
->sqpoll
= false;
8027 io_init_identity(&tctx
->__identity
);
8028 tctx
->identity
= &tctx
->__identity
;
8029 task
->io_uring
= tctx
;
8033 void __io_uring_free(struct task_struct
*tsk
)
8035 struct io_uring_task
*tctx
= tsk
->io_uring
;
8037 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
8038 WARN_ON_ONCE(refcount_read(&tctx
->identity
->count
) != 1);
8039 if (tctx
->identity
!= &tctx
->__identity
)
8040 kfree(tctx
->identity
);
8041 percpu_counter_destroy(&tctx
->inflight
);
8043 tsk
->io_uring
= NULL
;
8046 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
8047 struct io_uring_params
*p
)
8051 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8052 struct io_sq_data
*sqd
;
8055 if (!capable(CAP_SYS_ADMIN
) && !capable(CAP_SYS_NICE
))
8058 sqd
= io_get_sq_data(p
);
8065 io_sq_thread_park(sqd
);
8066 mutex_lock(&sqd
->ctx_lock
);
8067 list_add(&ctx
->sqd_list
, &sqd
->ctx_new_list
);
8068 mutex_unlock(&sqd
->ctx_lock
);
8069 io_sq_thread_unpark(sqd
);
8071 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
8072 if (!ctx
->sq_thread_idle
)
8073 ctx
->sq_thread_idle
= HZ
;
8078 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8079 int cpu
= p
->sq_thread_cpu
;
8082 if (cpu
>= nr_cpu_ids
)
8084 if (!cpu_online(cpu
))
8087 sqd
->thread
= kthread_create_on_cpu(io_sq_thread
, sqd
,
8088 cpu
, "io_uring-sq");
8090 sqd
->thread
= kthread_create(io_sq_thread
, sqd
,
8093 if (IS_ERR(sqd
->thread
)) {
8094 ret
= PTR_ERR(sqd
->thread
);
8098 ret
= io_uring_alloc_task_context(sqd
->thread
);
8101 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8102 /* Can't have SQ_AFF without SQPOLL */
8108 ret
= io_init_wq_offload(ctx
, p
);
8114 io_finish_async(ctx
);
8118 static void io_sq_offload_start(struct io_ring_ctx
*ctx
)
8120 struct io_sq_data
*sqd
= ctx
->sq_data
;
8122 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && sqd
->thread
)
8123 wake_up_process(sqd
->thread
);
8126 static inline void __io_unaccount_mem(struct user_struct
*user
,
8127 unsigned long nr_pages
)
8129 atomic_long_sub(nr_pages
, &user
->locked_vm
);
8132 static inline int __io_account_mem(struct user_struct
*user
,
8133 unsigned long nr_pages
)
8135 unsigned long page_limit
, cur_pages
, new_pages
;
8137 /* Don't allow more pages than we can safely lock */
8138 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
8141 cur_pages
= atomic_long_read(&user
->locked_vm
);
8142 new_pages
= cur_pages
+ nr_pages
;
8143 if (new_pages
> page_limit
)
8145 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
8146 new_pages
) != cur_pages
);
8151 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
8152 enum io_mem_account acct
)
8155 __io_unaccount_mem(ctx
->user
, nr_pages
);
8157 if (ctx
->mm_account
) {
8158 if (acct
== ACCT_LOCKED
)
8159 ctx
->mm_account
->locked_vm
-= nr_pages
;
8160 else if (acct
== ACCT_PINNED
)
8161 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8165 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
8166 enum io_mem_account acct
)
8170 if (ctx
->limit_mem
) {
8171 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8176 if (ctx
->mm_account
) {
8177 if (acct
== ACCT_LOCKED
)
8178 ctx
->mm_account
->locked_vm
+= nr_pages
;
8179 else if (acct
== ACCT_PINNED
)
8180 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8186 static void io_mem_free(void *ptr
)
8193 page
= virt_to_head_page(ptr
);
8194 if (put_page_testzero(page
))
8195 free_compound_page(page
);
8198 static void *io_mem_alloc(size_t size
)
8200 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8203 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8206 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8209 struct io_rings
*rings
;
8210 size_t off
, sq_array_size
;
8212 off
= struct_size(rings
, cqes
, cq_entries
);
8213 if (off
== SIZE_MAX
)
8217 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8225 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8226 if (sq_array_size
== SIZE_MAX
)
8229 if (check_add_overflow(off
, sq_array_size
, &off
))
8235 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
8239 pages
= (size_t)1 << get_order(
8240 rings_size(sq_entries
, cq_entries
, NULL
));
8241 pages
+= (size_t)1 << get_order(
8242 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
8247 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
8251 if (!ctx
->user_bufs
)
8254 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8255 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8257 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
8258 unpin_user_page(imu
->bvec
[j
].bv_page
);
8260 if (imu
->acct_pages
)
8261 io_unaccount_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8266 kfree(ctx
->user_bufs
);
8267 ctx
->user_bufs
= NULL
;
8268 ctx
->nr_user_bufs
= 0;
8272 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8273 void __user
*arg
, unsigned index
)
8275 struct iovec __user
*src
;
8277 #ifdef CONFIG_COMPAT
8279 struct compat_iovec __user
*ciovs
;
8280 struct compat_iovec ciov
;
8282 ciovs
= (struct compat_iovec __user
*) arg
;
8283 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8286 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8287 dst
->iov_len
= ciov
.iov_len
;
8291 src
= (struct iovec __user
*) arg
;
8292 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8298 * Not super efficient, but this is just a registration time. And we do cache
8299 * the last compound head, so generally we'll only do a full search if we don't
8302 * We check if the given compound head page has already been accounted, to
8303 * avoid double accounting it. This allows us to account the full size of the
8304 * page, not just the constituent pages of a huge page.
8306 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8307 int nr_pages
, struct page
*hpage
)
8311 /* check current page array */
8312 for (i
= 0; i
< nr_pages
; i
++) {
8313 if (!PageCompound(pages
[i
]))
8315 if (compound_head(pages
[i
]) == hpage
)
8319 /* check previously registered pages */
8320 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8321 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8323 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8324 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8326 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8334 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8335 int nr_pages
, struct io_mapped_ubuf
*imu
,
8336 struct page
**last_hpage
)
8340 for (i
= 0; i
< nr_pages
; i
++) {
8341 if (!PageCompound(pages
[i
])) {
8346 hpage
= compound_head(pages
[i
]);
8347 if (hpage
== *last_hpage
)
8349 *last_hpage
= hpage
;
8350 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8352 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8356 if (!imu
->acct_pages
)
8359 ret
= io_account_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8361 imu
->acct_pages
= 0;
8365 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8368 struct vm_area_struct
**vmas
= NULL
;
8369 struct page
**pages
= NULL
;
8370 struct page
*last_hpage
= NULL
;
8371 int i
, j
, got_pages
= 0;
8376 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8379 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
8381 if (!ctx
->user_bufs
)
8384 for (i
= 0; i
< nr_args
; i
++) {
8385 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8386 unsigned long off
, start
, end
, ubuf
;
8391 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8396 * Don't impose further limits on the size and buffer
8397 * constraints here, we'll -EINVAL later when IO is
8398 * submitted if they are wrong.
8401 if (!iov
.iov_base
|| !iov
.iov_len
)
8404 /* arbitrary limit, but we need something */
8405 if (iov
.iov_len
> SZ_1G
)
8408 ubuf
= (unsigned long) iov
.iov_base
;
8409 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8410 start
= ubuf
>> PAGE_SHIFT
;
8411 nr_pages
= end
- start
;
8414 if (!pages
|| nr_pages
> got_pages
) {
8417 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
8419 vmas
= kvmalloc_array(nr_pages
,
8420 sizeof(struct vm_area_struct
*),
8422 if (!pages
|| !vmas
) {
8426 got_pages
= nr_pages
;
8429 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8436 mmap_read_lock(current
->mm
);
8437 pret
= pin_user_pages(ubuf
, nr_pages
,
8438 FOLL_WRITE
| FOLL_LONGTERM
,
8440 if (pret
== nr_pages
) {
8441 /* don't support file backed memory */
8442 for (j
= 0; j
< nr_pages
; j
++) {
8443 struct vm_area_struct
*vma
= vmas
[j
];
8446 !is_file_hugepages(vma
->vm_file
)) {
8452 ret
= pret
< 0 ? pret
: -EFAULT
;
8454 mmap_read_unlock(current
->mm
);
8457 * if we did partial map, or found file backed vmas,
8458 * release any pages we did get
8461 unpin_user_pages(pages
, pret
);
8466 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, &last_hpage
);
8468 unpin_user_pages(pages
, pret
);
8473 off
= ubuf
& ~PAGE_MASK
;
8475 for (j
= 0; j
< nr_pages
; j
++) {
8478 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8479 imu
->bvec
[j
].bv_page
= pages
[j
];
8480 imu
->bvec
[j
].bv_len
= vec_len
;
8481 imu
->bvec
[j
].bv_offset
= off
;
8485 /* store original address for later verification */
8487 imu
->len
= iov
.iov_len
;
8488 imu
->nr_bvecs
= nr_pages
;
8490 ctx
->nr_user_bufs
++;
8498 io_sqe_buffer_unregister(ctx
);
8502 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8504 __s32 __user
*fds
= arg
;
8510 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8513 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8514 if (IS_ERR(ctx
->cq_ev_fd
)) {
8515 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8516 ctx
->cq_ev_fd
= NULL
;
8523 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8525 if (ctx
->cq_ev_fd
) {
8526 eventfd_ctx_put(ctx
->cq_ev_fd
);
8527 ctx
->cq_ev_fd
= NULL
;
8534 static int __io_destroy_buffers(int id
, void *p
, void *data
)
8536 struct io_ring_ctx
*ctx
= data
;
8537 struct io_buffer
*buf
= p
;
8539 __io_remove_buffers(ctx
, buf
, id
, -1U);
8543 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8545 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
8546 idr_destroy(&ctx
->io_buffer_idr
);
8549 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8551 io_finish_async(ctx
);
8552 io_sqe_buffer_unregister(ctx
);
8554 if (ctx
->sqo_task
) {
8555 put_task_struct(ctx
->sqo_task
);
8556 ctx
->sqo_task
= NULL
;
8557 mmdrop(ctx
->mm_account
);
8558 ctx
->mm_account
= NULL
;
8561 #ifdef CONFIG_BLK_CGROUP
8562 if (ctx
->sqo_blkcg_css
)
8563 css_put(ctx
->sqo_blkcg_css
);
8566 io_sqe_files_unregister(ctx
);
8567 io_eventfd_unregister(ctx
);
8568 io_destroy_buffers(ctx
);
8569 idr_destroy(&ctx
->personality_idr
);
8571 #if defined(CONFIG_UNIX)
8572 if (ctx
->ring_sock
) {
8573 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8574 sock_release(ctx
->ring_sock
);
8578 io_mem_free(ctx
->rings
);
8579 io_mem_free(ctx
->sq_sqes
);
8581 percpu_ref_exit(&ctx
->refs
);
8582 free_uid(ctx
->user
);
8583 put_cred(ctx
->creds
);
8584 kfree(ctx
->cancel_hash
);
8585 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
8589 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8591 struct io_ring_ctx
*ctx
= file
->private_data
;
8594 poll_wait(file
, &ctx
->cq_wait
, wait
);
8596 * synchronizes with barrier from wq_has_sleeper call in
8600 if (!io_sqring_full(ctx
))
8601 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8602 if (io_cqring_events(ctx
, false))
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_remove_personalities(int id
, void *p
, void *data
)
8617 struct io_ring_ctx
*ctx
= data
;
8618 struct io_identity
*iod
;
8620 iod
= idr_remove(&ctx
->personality_idr
, id
);
8622 put_cred(iod
->creds
);
8623 if (refcount_dec_and_test(&iod
->count
))
8629 static void io_ring_exit_work(struct work_struct
*work
)
8631 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
8635 * If we're doing polled IO and end up having requests being
8636 * submitted async (out-of-line), then completions can come in while
8637 * we're waiting for refs to drop. We need to reap these manually,
8638 * as nobody else will be looking for them.
8641 io_iopoll_try_reap_events(ctx
);
8642 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8643 io_ring_ctx_free(ctx
);
8646 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8648 mutex_lock(&ctx
->uring_lock
);
8649 percpu_ref_kill(&ctx
->refs
);
8651 io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8652 mutex_unlock(&ctx
->uring_lock
);
8654 io_kill_timeouts(ctx
, NULL
, NULL
);
8655 io_poll_remove_all(ctx
, NULL
, NULL
);
8658 io_wq_cancel_all(ctx
->io_wq
);
8660 /* if we failed setting up the ctx, we might not have any rings */
8661 io_iopoll_try_reap_events(ctx
);
8662 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
8665 * Do this upfront, so we won't have a grace period where the ring
8666 * is closed but resources aren't reaped yet. This can cause
8667 * spurious failure in setting up a new ring.
8669 io_unaccount_mem(ctx
, ring_pages(ctx
->sq_entries
, ctx
->cq_entries
),
8672 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8674 * Use system_unbound_wq to avoid spawning tons of event kworkers
8675 * if we're exiting a ton of rings at the same time. It just adds
8676 * noise and overhead, there's no discernable change in runtime
8677 * over using system_wq.
8679 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8682 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8684 struct io_ring_ctx
*ctx
= file
->private_data
;
8686 file
->private_data
= NULL
;
8687 io_ring_ctx_wait_and_kill(ctx
);
8691 struct io_task_cancel
{
8692 struct task_struct
*task
;
8693 struct files_struct
*files
;
8696 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8698 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8699 struct io_task_cancel
*cancel
= data
;
8702 if (cancel
->files
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
8703 unsigned long flags
;
8704 struct io_ring_ctx
*ctx
= req
->ctx
;
8706 /* protect against races with linked timeouts */
8707 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
8708 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8709 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
8711 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8716 static void io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8717 struct task_struct
*task
,
8718 struct files_struct
*files
)
8720 struct io_defer_entry
*de
= NULL
;
8723 spin_lock_irq(&ctx
->completion_lock
);
8724 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8725 if (io_match_task(de
->req
, task
, files
)) {
8726 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8730 spin_unlock_irq(&ctx
->completion_lock
);
8732 while (!list_empty(&list
)) {
8733 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8734 list_del_init(&de
->list
);
8735 req_set_fail_links(de
->req
);
8736 io_put_req(de
->req
);
8737 io_req_complete(de
->req
, -ECANCELED
);
8742 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8743 struct task_struct
*task
,
8744 struct files_struct
*files
)
8746 while (!list_empty_careful(&ctx
->inflight_list
)) {
8747 struct io_task_cancel cancel
= { .task
= task
, .files
= files
};
8748 struct io_kiocb
*req
;
8752 spin_lock_irq(&ctx
->inflight_lock
);
8753 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
8754 if (req
->task
!= task
||
8755 req
->work
.identity
->files
!= files
)
8761 prepare_to_wait(&task
->io_uring
->wait
, &wait
,
8762 TASK_UNINTERRUPTIBLE
);
8763 spin_unlock_irq(&ctx
->inflight_lock
);
8765 /* We need to keep going until we don't find a matching req */
8769 io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, &cancel
, true);
8770 io_poll_remove_all(ctx
, task
, files
);
8771 io_kill_timeouts(ctx
, task
, files
);
8772 /* cancellations _may_ trigger task work */
8775 finish_wait(&task
->io_uring
->wait
, &wait
);
8779 static void __io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8780 struct task_struct
*task
)
8783 struct io_task_cancel cancel
= { .task
= task
, .files
= NULL
, };
8784 enum io_wq_cancel cret
;
8787 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, &cancel
, true);
8788 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8791 /* SQPOLL thread does its own polling */
8792 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8793 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8794 io_iopoll_try_reap_events(ctx
);
8799 ret
|= io_poll_remove_all(ctx
, task
, NULL
);
8800 ret
|= io_kill_timeouts(ctx
, task
, NULL
);
8809 * We need to iteratively cancel requests, in case a request has dependent
8810 * hard links. These persist even for failure of cancelations, hence keep
8811 * looping until none are found.
8813 static void io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8814 struct files_struct
*files
)
8816 struct task_struct
*task
= current
;
8818 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
) {
8819 task
= ctx
->sq_data
->thread
;
8820 atomic_inc(&task
->io_uring
->in_idle
);
8821 io_sq_thread_park(ctx
->sq_data
);
8824 io_cancel_defer_files(ctx
, task
, files
);
8825 io_ring_submit_lock(ctx
, (ctx
->flags
& IORING_SETUP_IOPOLL
));
8826 io_cqring_overflow_flush(ctx
, true, task
, files
);
8827 io_ring_submit_unlock(ctx
, (ctx
->flags
& IORING_SETUP_IOPOLL
));
8830 __io_uring_cancel_task_requests(ctx
, task
);
8832 io_uring_cancel_files(ctx
, task
, files
);
8834 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
) {
8835 atomic_dec(&task
->io_uring
->in_idle
);
8837 * If the files that are going away are the ones in the thread
8838 * identity, clear them out.
8840 if (task
->io_uring
->identity
->files
== files
)
8841 task
->io_uring
->identity
->files
= NULL
;
8842 io_sq_thread_unpark(ctx
->sq_data
);
8847 * Note that this task has used io_uring. We use it for cancelation purposes.
8849 static int io_uring_add_task_file(struct io_ring_ctx
*ctx
, struct file
*file
)
8851 struct io_uring_task
*tctx
= current
->io_uring
;
8853 if (unlikely(!tctx
)) {
8856 ret
= io_uring_alloc_task_context(current
);
8859 tctx
= current
->io_uring
;
8861 if (tctx
->last
!= file
) {
8862 void *old
= xa_load(&tctx
->xa
, (unsigned long)file
);
8866 xa_store(&tctx
->xa
, (unsigned long)file
, file
, GFP_KERNEL
);
8872 * This is race safe in that the task itself is doing this, hence it
8873 * cannot be going through the exit/cancel paths at the same time.
8874 * This cannot be modified while exit/cancel is running.
8876 if (!tctx
->sqpoll
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
8877 tctx
->sqpoll
= true;
8883 * Remove this io_uring_file -> task mapping.
8885 static void io_uring_del_task_file(struct file
*file
)
8887 struct io_uring_task
*tctx
= current
->io_uring
;
8889 if (tctx
->last
== file
)
8891 file
= xa_erase(&tctx
->xa
, (unsigned long)file
);
8897 * Drop task note for this file if we're the only ones that hold it after
8900 static void io_uring_attempt_task_drop(struct file
*file
)
8902 if (!current
->io_uring
)
8905 * fput() is pending, will be 2 if the only other ref is our potential
8906 * task file note. If the task is exiting, drop regardless of count.
8908 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
) ||
8909 atomic_long_read(&file
->f_count
) == 2)
8910 io_uring_del_task_file(file
);
8913 void __io_uring_files_cancel(struct files_struct
*files
)
8915 struct io_uring_task
*tctx
= current
->io_uring
;
8917 unsigned long index
;
8919 /* make sure overflow events are dropped */
8920 atomic_inc(&tctx
->in_idle
);
8922 xa_for_each(&tctx
->xa
, index
, file
) {
8923 struct io_ring_ctx
*ctx
= file
->private_data
;
8925 io_uring_cancel_task_requests(ctx
, files
);
8927 io_uring_del_task_file(file
);
8930 atomic_dec(&tctx
->in_idle
);
8933 static s64
tctx_inflight(struct io_uring_task
*tctx
)
8935 unsigned long index
;
8939 inflight
= percpu_counter_sum(&tctx
->inflight
);
8944 * If we have SQPOLL rings, then we need to iterate and find them, and
8945 * add the pending count for those.
8947 xa_for_each(&tctx
->xa
, index
, file
) {
8948 struct io_ring_ctx
*ctx
= file
->private_data
;
8950 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8951 struct io_uring_task
*__tctx
= ctx
->sqo_task
->io_uring
;
8953 inflight
+= percpu_counter_sum(&__tctx
->inflight
);
8961 * Find any io_uring fd that this task has registered or done IO on, and cancel
8964 void __io_uring_task_cancel(void)
8966 struct io_uring_task
*tctx
= current
->io_uring
;
8970 /* make sure overflow events are dropped */
8971 atomic_inc(&tctx
->in_idle
);
8974 /* read completions before cancelations */
8975 inflight
= tctx_inflight(tctx
);
8978 __io_uring_files_cancel(NULL
);
8980 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
8983 * If we've seen completions, retry. This avoids a race where
8984 * a completion comes in before we did prepare_to_wait().
8986 if (inflight
!= tctx_inflight(tctx
))
8991 finish_wait(&tctx
->wait
, &wait
);
8992 atomic_dec(&tctx
->in_idle
);
8995 static int io_uring_flush(struct file
*file
, void *data
)
8997 io_uring_attempt_task_drop(file
);
9001 static void *io_uring_validate_mmap_request(struct file
*file
,
9002 loff_t pgoff
, size_t sz
)
9004 struct io_ring_ctx
*ctx
= file
->private_data
;
9005 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9010 case IORING_OFF_SQ_RING
:
9011 case IORING_OFF_CQ_RING
:
9014 case IORING_OFF_SQES
:
9018 return ERR_PTR(-EINVAL
);
9021 page
= virt_to_head_page(ptr
);
9022 if (sz
> page_size(page
))
9023 return ERR_PTR(-EINVAL
);
9030 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9032 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9036 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9038 return PTR_ERR(ptr
);
9040 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9041 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9044 #else /* !CONFIG_MMU */
9046 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9048 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9051 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9053 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9056 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9057 unsigned long addr
, unsigned long len
,
9058 unsigned long pgoff
, unsigned long flags
)
9062 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9064 return PTR_ERR(ptr
);
9066 return (unsigned long) ptr
;
9069 #endif /* !CONFIG_MMU */
9071 static void io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9076 if (!io_sqring_full(ctx
))
9079 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9081 if (!io_sqring_full(ctx
))
9085 } while (!signal_pending(current
));
9087 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9090 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9091 struct __kernel_timespec __user
**ts
,
9092 const sigset_t __user
**sig
)
9094 struct io_uring_getevents_arg arg
;
9097 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9098 * is just a pointer to the sigset_t.
9100 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9101 *sig
= (const sigset_t __user
*) argp
;
9107 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9108 * timespec and sigset_t pointers if good.
9110 if (*argsz
!= sizeof(arg
))
9112 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9114 *sig
= u64_to_user_ptr(arg
.sigmask
);
9115 *argsz
= arg
.sigmask_sz
;
9116 *ts
= u64_to_user_ptr(arg
.ts
);
9120 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9121 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9124 struct io_ring_ctx
*ctx
;
9131 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9132 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
))
9140 if (f
.file
->f_op
!= &io_uring_fops
)
9144 ctx
= f
.file
->private_data
;
9145 if (!percpu_ref_tryget(&ctx
->refs
))
9149 if (ctx
->flags
& IORING_SETUP_R_DISABLED
)
9153 * For SQ polling, the thread will do all submissions and completions.
9154 * Just return the requested submit count, and wake the thread if
9158 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9159 io_ring_submit_lock(ctx
, (ctx
->flags
& IORING_SETUP_IOPOLL
));
9160 if (!list_empty_careful(&ctx
->cq_overflow_list
))
9161 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
9162 io_ring_submit_unlock(ctx
, (ctx
->flags
& IORING_SETUP_IOPOLL
));
9163 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9164 wake_up(&ctx
->sq_data
->wait
);
9165 if (flags
& IORING_ENTER_SQ_WAIT
)
9166 io_sqpoll_wait_sq(ctx
);
9167 submitted
= to_submit
;
9168 } else if (to_submit
) {
9169 ret
= io_uring_add_task_file(ctx
, f
.file
);
9172 mutex_lock(&ctx
->uring_lock
);
9173 submitted
= io_submit_sqes(ctx
, to_submit
);
9174 mutex_unlock(&ctx
->uring_lock
);
9176 if (submitted
!= to_submit
)
9179 if (flags
& IORING_ENTER_GETEVENTS
) {
9180 const sigset_t __user
*sig
;
9181 struct __kernel_timespec __user
*ts
;
9183 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
9187 min_complete
= min(min_complete
, ctx
->cq_entries
);
9190 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9191 * space applications don't need to do io completion events
9192 * polling again, they can rely on io_sq_thread to do polling
9193 * work, which can reduce cpu usage and uring_lock contention.
9195 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
9196 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9197 ret
= io_iopoll_check(ctx
, min_complete
);
9199 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
9204 percpu_ref_put(&ctx
->refs
);
9207 return submitted
? submitted
: ret
;
9210 #ifdef CONFIG_PROC_FS
9211 static int io_uring_show_cred(int id
, void *p
, void *data
)
9213 struct io_identity
*iod
= p
;
9214 const struct cred
*cred
= iod
->creds
;
9215 struct seq_file
*m
= data
;
9216 struct user_namespace
*uns
= seq_user_ns(m
);
9217 struct group_info
*gi
;
9222 seq_printf(m
, "%5d\n", id
);
9223 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
9224 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
9225 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
9226 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
9227 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
9228 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
9229 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
9230 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
9231 seq_puts(m
, "\n\tGroups:\t");
9232 gi
= cred
->group_info
;
9233 for (g
= 0; g
< gi
->ngroups
; g
++) {
9234 seq_put_decimal_ull(m
, g
? " " : "",
9235 from_kgid_munged(uns
, gi
->gid
[g
]));
9237 seq_puts(m
, "\n\tCapEff:\t");
9238 cap
= cred
->cap_effective
;
9239 CAP_FOR_EACH_U32(__capi
)
9240 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
9245 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
9247 struct io_sq_data
*sq
= NULL
;
9252 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9253 * since fdinfo case grabs it in the opposite direction of normal use
9254 * cases. If we fail to get the lock, we just don't iterate any
9255 * structures that could be going away outside the io_uring mutex.
9257 has_lock
= mutex_trylock(&ctx
->uring_lock
);
9259 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
9262 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
9263 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
9264 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
9265 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
9266 struct fixed_file_table
*table
;
9269 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
9270 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
9272 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
9274 seq_printf(m
, "%5u: <none>\n", i
);
9276 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
9277 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
9278 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
9280 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
9281 (unsigned int) buf
->len
);
9283 if (has_lock
&& !idr_is_empty(&ctx
->personality_idr
)) {
9284 seq_printf(m
, "Personalities:\n");
9285 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
9287 seq_printf(m
, "PollList:\n");
9288 spin_lock_irq(&ctx
->completion_lock
);
9289 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9290 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9291 struct io_kiocb
*req
;
9293 hlist_for_each_entry(req
, list
, hash_node
)
9294 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9295 req
->task
->task_works
!= NULL
);
9297 spin_unlock_irq(&ctx
->completion_lock
);
9299 mutex_unlock(&ctx
->uring_lock
);
9302 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9304 struct io_ring_ctx
*ctx
= f
->private_data
;
9306 if (percpu_ref_tryget(&ctx
->refs
)) {
9307 __io_uring_show_fdinfo(ctx
, m
);
9308 percpu_ref_put(&ctx
->refs
);
9313 static const struct file_operations io_uring_fops
= {
9314 .release
= io_uring_release
,
9315 .flush
= io_uring_flush
,
9316 .mmap
= io_uring_mmap
,
9318 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9319 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9321 .poll
= io_uring_poll
,
9322 .fasync
= io_uring_fasync
,
9323 #ifdef CONFIG_PROC_FS
9324 .show_fdinfo
= io_uring_show_fdinfo
,
9328 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9329 struct io_uring_params
*p
)
9331 struct io_rings
*rings
;
9332 size_t size
, sq_array_offset
;
9334 /* make sure these are sane, as we already accounted them */
9335 ctx
->sq_entries
= p
->sq_entries
;
9336 ctx
->cq_entries
= p
->cq_entries
;
9338 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9339 if (size
== SIZE_MAX
)
9342 rings
= io_mem_alloc(size
);
9347 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9348 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9349 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9350 rings
->sq_ring_entries
= p
->sq_entries
;
9351 rings
->cq_ring_entries
= p
->cq_entries
;
9352 ctx
->sq_mask
= rings
->sq_ring_mask
;
9353 ctx
->cq_mask
= rings
->cq_ring_mask
;
9355 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9356 if (size
== SIZE_MAX
) {
9357 io_mem_free(ctx
->rings
);
9362 ctx
->sq_sqes
= io_mem_alloc(size
);
9363 if (!ctx
->sq_sqes
) {
9364 io_mem_free(ctx
->rings
);
9373 * Allocate an anonymous fd, this is what constitutes the application
9374 * visible backing of an io_uring instance. The application mmaps this
9375 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9376 * we have to tie this fd to a socket for file garbage collection purposes.
9378 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
9384 #if defined(CONFIG_UNIX)
9385 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9391 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9396 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9397 O_RDWR
| O_CLOEXEC
);
9400 ret
= PTR_ERR(file
);
9404 #if defined(CONFIG_UNIX)
9405 ctx
->ring_sock
->file
= file
;
9407 ret
= io_uring_add_task_file(ctx
, file
);
9413 fd_install(fd
, file
);
9416 #if defined(CONFIG_UNIX)
9417 sock_release(ctx
->ring_sock
);
9418 ctx
->ring_sock
= NULL
;
9423 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9424 struct io_uring_params __user
*params
)
9426 struct user_struct
*user
= NULL
;
9427 struct io_ring_ctx
*ctx
;
9433 if (entries
> IORING_MAX_ENTRIES
) {
9434 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9436 entries
= IORING_MAX_ENTRIES
;
9440 * Use twice as many entries for the CQ ring. It's possible for the
9441 * application to drive a higher depth than the size of the SQ ring,
9442 * since the sqes are only used at submission time. This allows for
9443 * some flexibility in overcommitting a bit. If the application has
9444 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9445 * of CQ ring entries manually.
9447 p
->sq_entries
= roundup_pow_of_two(entries
);
9448 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9450 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9451 * to a power-of-two, if it isn't already. We do NOT impose
9452 * any cq vs sq ring sizing.
9456 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9457 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9459 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9461 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9462 if (p
->cq_entries
< p
->sq_entries
)
9465 p
->cq_entries
= 2 * p
->sq_entries
;
9468 user
= get_uid(current_user());
9469 limit_mem
= !capable(CAP_IPC_LOCK
);
9472 ret
= __io_account_mem(user
,
9473 ring_pages(p
->sq_entries
, p
->cq_entries
));
9480 ctx
= io_ring_ctx_alloc(p
);
9483 __io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
9488 ctx
->compat
= in_compat_syscall();
9490 ctx
->creds
= get_current_cred();
9492 ctx
->loginuid
= current
->loginuid
;
9493 ctx
->sessionid
= current
->sessionid
;
9495 ctx
->sqo_task
= get_task_struct(current
);
9498 * This is just grabbed for accounting purposes. When a process exits,
9499 * the mm is exited and dropped before the files, hence we need to hang
9500 * on to this mm purely for the purposes of being able to unaccount
9501 * memory (locked/pinned vm). It's not used for anything else.
9503 mmgrab(current
->mm
);
9504 ctx
->mm_account
= current
->mm
;
9506 #ifdef CONFIG_BLK_CGROUP
9508 * The sq thread will belong to the original cgroup it was inited in.
9509 * If the cgroup goes offline (e.g. disabling the io controller), then
9510 * issued bios will be associated with the closest cgroup later in the
9514 ctx
->sqo_blkcg_css
= blkcg_css();
9515 ret
= css_tryget_online(ctx
->sqo_blkcg_css
);
9518 /* don't init against a dying cgroup, have the user try again */
9519 ctx
->sqo_blkcg_css
= NULL
;
9526 * Account memory _before_ installing the file descriptor. Once
9527 * the descriptor is installed, it can get closed at any time. Also
9528 * do this before hitting the general error path, as ring freeing
9529 * will un-account as well.
9531 io_account_mem(ctx
, ring_pages(p
->sq_entries
, p
->cq_entries
),
9533 ctx
->limit_mem
= limit_mem
;
9535 ret
= io_allocate_scq_urings(ctx
, p
);
9539 ret
= io_sq_offload_create(ctx
, p
);
9543 if (!(p
->flags
& IORING_SETUP_R_DISABLED
))
9544 io_sq_offload_start(ctx
);
9546 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9547 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9548 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9549 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9550 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9551 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9552 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9553 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9555 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9556 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9557 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9558 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9559 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9560 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9561 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9562 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9564 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9565 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9566 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9567 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
9568 IORING_FEAT_EXT_ARG
;
9570 if (copy_to_user(params
, p
, sizeof(*p
))) {
9576 * Install ring fd as the very last thing, so we don't risk someone
9577 * having closed it before we finish setup
9579 ret
= io_uring_get_fd(ctx
);
9583 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9586 io_ring_ctx_wait_and_kill(ctx
);
9591 * Sets up an aio uring context, and returns the fd. Applications asks for a
9592 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9593 * params structure passed in.
9595 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9597 struct io_uring_params p
;
9600 if (copy_from_user(&p
, params
, sizeof(p
)))
9602 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9607 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9608 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9609 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9610 IORING_SETUP_R_DISABLED
))
9613 return io_uring_create(entries
, &p
, params
);
9616 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9617 struct io_uring_params __user
*, params
)
9619 return io_uring_setup(entries
, params
);
9622 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9624 struct io_uring_probe
*p
;
9628 size
= struct_size(p
, ops
, nr_args
);
9629 if (size
== SIZE_MAX
)
9631 p
= kzalloc(size
, GFP_KERNEL
);
9636 if (copy_from_user(p
, arg
, size
))
9639 if (memchr_inv(p
, 0, size
))
9642 p
->last_op
= IORING_OP_LAST
- 1;
9643 if (nr_args
> IORING_OP_LAST
)
9644 nr_args
= IORING_OP_LAST
;
9646 for (i
= 0; i
< nr_args
; i
++) {
9648 if (!io_op_defs
[i
].not_supported
)
9649 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9654 if (copy_to_user(arg
, p
, size
))
9661 static int io_register_personality(struct io_ring_ctx
*ctx
)
9663 struct io_identity
*id
;
9666 id
= kmalloc(sizeof(*id
), GFP_KERNEL
);
9670 io_init_identity(id
);
9671 id
->creds
= get_current_cred();
9673 ret
= idr_alloc_cyclic(&ctx
->personality_idr
, id
, 1, USHRT_MAX
, GFP_KERNEL
);
9675 put_cred(id
->creds
);
9681 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
9683 struct io_identity
*iod
;
9685 iod
= idr_remove(&ctx
->personality_idr
, id
);
9687 put_cred(iod
->creds
);
9688 if (refcount_dec_and_test(&iod
->count
))
9696 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9697 unsigned int nr_args
)
9699 struct io_uring_restriction
*res
;
9703 /* Restrictions allowed only if rings started disabled */
9704 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9707 /* We allow only a single restrictions registration */
9708 if (ctx
->restrictions
.registered
)
9711 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9714 size
= array_size(nr_args
, sizeof(*res
));
9715 if (size
== SIZE_MAX
)
9718 res
= memdup_user(arg
, size
);
9720 return PTR_ERR(res
);
9724 for (i
= 0; i
< nr_args
; i
++) {
9725 switch (res
[i
].opcode
) {
9726 case IORING_RESTRICTION_REGISTER_OP
:
9727 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9732 __set_bit(res
[i
].register_op
,
9733 ctx
->restrictions
.register_op
);
9735 case IORING_RESTRICTION_SQE_OP
:
9736 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9741 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9743 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9744 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9746 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9747 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9756 /* Reset all restrictions if an error happened */
9758 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9760 ctx
->restrictions
.registered
= true;
9766 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9768 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9771 if (ctx
->restrictions
.registered
)
9772 ctx
->restricted
= 1;
9774 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9776 io_sq_offload_start(ctx
);
9781 static bool io_register_op_must_quiesce(int op
)
9784 case IORING_UNREGISTER_FILES
:
9785 case IORING_REGISTER_FILES_UPDATE
:
9786 case IORING_REGISTER_PROBE
:
9787 case IORING_REGISTER_PERSONALITY
:
9788 case IORING_UNREGISTER_PERSONALITY
:
9795 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
9796 void __user
*arg
, unsigned nr_args
)
9797 __releases(ctx
->uring_lock
)
9798 __acquires(ctx
->uring_lock
)
9803 * We're inside the ring mutex, if the ref is already dying, then
9804 * someone else killed the ctx or is already going through
9805 * io_uring_register().
9807 if (percpu_ref_is_dying(&ctx
->refs
))
9810 if (io_register_op_must_quiesce(opcode
)) {
9811 percpu_ref_kill(&ctx
->refs
);
9814 * Drop uring mutex before waiting for references to exit. If
9815 * another thread is currently inside io_uring_enter() it might
9816 * need to grab the uring_lock to make progress. If we hold it
9817 * here across the drain wait, then we can deadlock. It's safe
9818 * to drop the mutex here, since no new references will come in
9819 * after we've killed the percpu ref.
9821 mutex_unlock(&ctx
->uring_lock
);
9823 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
9826 ret
= io_run_task_work_sig();
9831 mutex_lock(&ctx
->uring_lock
);
9834 percpu_ref_resurrect(&ctx
->refs
);
9839 if (ctx
->restricted
) {
9840 if (opcode
>= IORING_REGISTER_LAST
) {
9845 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
9852 case IORING_REGISTER_BUFFERS
:
9853 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
9855 case IORING_UNREGISTER_BUFFERS
:
9859 ret
= io_sqe_buffer_unregister(ctx
);
9861 case IORING_REGISTER_FILES
:
9862 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
9864 case IORING_UNREGISTER_FILES
:
9868 ret
= io_sqe_files_unregister(ctx
);
9870 case IORING_REGISTER_FILES_UPDATE
:
9871 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
9873 case IORING_REGISTER_EVENTFD
:
9874 case IORING_REGISTER_EVENTFD_ASYNC
:
9878 ret
= io_eventfd_register(ctx
, arg
);
9881 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
9882 ctx
->eventfd_async
= 1;
9884 ctx
->eventfd_async
= 0;
9886 case IORING_UNREGISTER_EVENTFD
:
9890 ret
= io_eventfd_unregister(ctx
);
9892 case IORING_REGISTER_PROBE
:
9894 if (!arg
|| nr_args
> 256)
9896 ret
= io_probe(ctx
, arg
, nr_args
);
9898 case IORING_REGISTER_PERSONALITY
:
9902 ret
= io_register_personality(ctx
);
9904 case IORING_UNREGISTER_PERSONALITY
:
9908 ret
= io_unregister_personality(ctx
, nr_args
);
9910 case IORING_REGISTER_ENABLE_RINGS
:
9914 ret
= io_register_enable_rings(ctx
);
9916 case IORING_REGISTER_RESTRICTIONS
:
9917 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
9925 if (io_register_op_must_quiesce(opcode
)) {
9926 /* bring the ctx back to life */
9927 percpu_ref_reinit(&ctx
->refs
);
9929 reinit_completion(&ctx
->ref_comp
);
9934 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
9935 void __user
*, arg
, unsigned int, nr_args
)
9937 struct io_ring_ctx
*ctx
;
9946 if (f
.file
->f_op
!= &io_uring_fops
)
9949 ctx
= f
.file
->private_data
;
9951 mutex_lock(&ctx
->uring_lock
);
9952 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
9953 mutex_unlock(&ctx
->uring_lock
);
9954 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
9955 ctx
->cq_ev_fd
!= NULL
, ret
);
9961 static int __init
io_uring_init(void)
9963 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
9964 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
9965 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
9968 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
9969 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
9970 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
9971 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
9972 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
9973 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
9974 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
9975 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
9976 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
9977 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
9978 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
9979 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
9980 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
9981 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
9982 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
9983 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
9984 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
9985 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
9986 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
9987 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
9988 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
9989 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
9990 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
9991 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
9992 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
9993 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
9994 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
9995 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
9996 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
9997 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
9998 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
10000 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
10001 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
10002 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
10005 __initcall(io_uring_init
);