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
;
210 struct fixed_file_data
{
211 struct fixed_file_table
*table
;
212 struct io_ring_ctx
*ctx
;
214 struct fixed_file_ref_node
*node
;
215 struct percpu_ref refs
;
216 struct completion done
;
217 struct list_head ref_list
;
222 struct list_head list
;
228 struct io_restriction
{
229 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
230 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
231 u8 sqe_flags_allowed
;
232 u8 sqe_flags_required
;
240 /* ctx's that are using this sqd */
241 struct list_head ctx_list
;
242 struct list_head ctx_new_list
;
243 struct mutex ctx_lock
;
245 struct task_struct
*thread
;
246 struct wait_queue_head wait
;
251 struct percpu_ref refs
;
252 } ____cacheline_aligned_in_smp
;
256 unsigned int compat
: 1;
257 unsigned int limit_mem
: 1;
258 unsigned int cq_overflow_flushed
: 1;
259 unsigned int drain_next
: 1;
260 unsigned int eventfd_async
: 1;
261 unsigned int restricted
: 1;
264 * Ring buffer of indices into array of io_uring_sqe, which is
265 * mmapped by the application using the IORING_OFF_SQES offset.
267 * This indirection could e.g. be used to assign fixed
268 * io_uring_sqe entries to operations and only submit them to
269 * the queue when needed.
271 * The kernel modifies neither the indices array nor the entries
275 unsigned cached_sq_head
;
278 unsigned sq_thread_idle
;
279 unsigned cached_sq_dropped
;
280 unsigned cached_cq_overflow
;
281 unsigned long sq_check_overflow
;
283 struct list_head defer_list
;
284 struct list_head timeout_list
;
285 struct list_head cq_overflow_list
;
287 wait_queue_head_t inflight_wait
;
288 struct io_uring_sqe
*sq_sqes
;
289 } ____cacheline_aligned_in_smp
;
291 struct io_rings
*rings
;
297 * For SQPOLL usage - we hold a reference to the parent task, so we
298 * have access to the ->files
300 struct task_struct
*sqo_task
;
302 /* Only used for accounting purposes */
303 struct mm_struct
*mm_account
;
305 #ifdef CONFIG_BLK_CGROUP
306 struct cgroup_subsys_state
*sqo_blkcg_css
;
309 struct io_sq_data
*sq_data
; /* if using sq thread polling */
311 struct wait_queue_head sqo_sq_wait
;
312 struct wait_queue_entry sqo_wait_entry
;
313 struct list_head sqd_list
;
316 * If used, fixed file set. Writers must ensure that ->refs is dead,
317 * readers must ensure that ->refs is alive as long as the file* is
318 * used. Only updated through io_uring_register(2).
320 struct fixed_file_data
*file_data
;
321 unsigned nr_user_files
;
323 /* if used, fixed mapped user buffers */
324 unsigned nr_user_bufs
;
325 struct io_mapped_ubuf
*user_bufs
;
327 struct user_struct
*user
;
329 const struct cred
*creds
;
333 unsigned int sessionid
;
336 struct completion ref_comp
;
337 struct completion sq_thread_comp
;
339 /* if all else fails... */
340 struct io_kiocb
*fallback_req
;
342 #if defined(CONFIG_UNIX)
343 struct socket
*ring_sock
;
346 struct idr io_buffer_idr
;
348 struct idr personality_idr
;
351 unsigned cached_cq_tail
;
354 atomic_t cq_timeouts
;
355 unsigned long cq_check_overflow
;
356 struct wait_queue_head cq_wait
;
357 struct fasync_struct
*cq_fasync
;
358 struct eventfd_ctx
*cq_ev_fd
;
359 } ____cacheline_aligned_in_smp
;
362 struct mutex uring_lock
;
363 wait_queue_head_t wait
;
364 } ____cacheline_aligned_in_smp
;
367 spinlock_t completion_lock
;
370 * ->iopoll_list is protected by the ctx->uring_lock for
371 * io_uring instances that don't use IORING_SETUP_SQPOLL.
372 * For SQPOLL, only the single threaded io_sq_thread() will
373 * manipulate the list, hence no extra locking is needed there.
375 struct list_head iopoll_list
;
376 struct hlist_head
*cancel_hash
;
377 unsigned cancel_hash_bits
;
378 bool poll_multi_file
;
380 spinlock_t inflight_lock
;
381 struct list_head inflight_list
;
382 } ____cacheline_aligned_in_smp
;
384 struct delayed_work file_put_work
;
385 struct llist_head file_put_llist
;
387 struct work_struct exit_work
;
388 struct io_restriction restrictions
;
392 * First field must be the file pointer in all the
393 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
395 struct io_poll_iocb
{
398 struct wait_queue_head
*head
;
404 struct wait_queue_entry wait
;
409 struct file
*put_file
;
413 struct io_timeout_data
{
414 struct io_kiocb
*req
;
415 struct hrtimer timer
;
416 struct timespec64 ts
;
417 enum hrtimer_mode mode
;
422 struct sockaddr __user
*addr
;
423 int __user
*addr_len
;
425 unsigned long nofile
;
445 struct list_head list
;
448 struct io_timeout_rem
{
454 /* NOTE: kiocb has the file as the first member, so don't do it here */
462 struct sockaddr __user
*addr
;
469 struct user_msghdr __user
*umsg
;
475 struct io_buffer
*kbuf
;
481 struct filename
*filename
;
483 unsigned long nofile
;
486 struct io_files_update
{
512 struct epoll_event event
;
516 struct file
*file_out
;
517 struct file
*file_in
;
524 struct io_provide_buf
{
538 const char __user
*filename
;
539 struct statx __user
*buffer
;
542 struct io_completion
{
544 struct list_head list
;
548 struct io_async_connect
{
549 struct sockaddr_storage address
;
552 struct io_async_msghdr
{
553 struct iovec fast_iov
[UIO_FASTIOV
];
555 struct sockaddr __user
*uaddr
;
557 struct sockaddr_storage addr
;
561 struct iovec fast_iov
[UIO_FASTIOV
];
562 const struct iovec
*free_iovec
;
563 struct iov_iter iter
;
565 struct wait_page_queue wpq
;
569 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
570 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
571 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
572 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
573 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
574 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
581 REQ_F_LINK_TIMEOUT_BIT
,
583 REQ_F_NEED_CLEANUP_BIT
,
585 REQ_F_BUFFER_SELECTED_BIT
,
586 REQ_F_NO_FILE_TABLE_BIT
,
587 REQ_F_WORK_INITIALIZED_BIT
,
588 REQ_F_LTIMEOUT_ACTIVE_BIT
,
590 /* not a real bit, just to check we're not overflowing the space */
596 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
597 /* drain existing IO first */
598 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
600 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
601 /* doesn't sever on completion < 0 */
602 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
604 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
605 /* IOSQE_BUFFER_SELECT */
606 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
609 REQ_F_LINK_HEAD
= BIT(REQ_F_LINK_HEAD_BIT
),
610 /* fail rest of links */
611 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
612 /* on inflight list */
613 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
614 /* read/write uses file position */
615 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
616 /* must not punt to workers */
617 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
618 /* has or had linked timeout */
619 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
621 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
623 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
624 /* already went through poll handler */
625 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
626 /* buffer already selected */
627 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
628 /* doesn't need file table for this request */
629 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
630 /* io_wq_work is initialized */
631 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
632 /* linked timeout is active, i.e. prepared by link's head */
633 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
637 struct io_poll_iocb poll
;
638 struct io_poll_iocb
*double_poll
;
642 * NOTE! Each of the iocb union members has the file pointer
643 * as the first entry in their struct definition. So you can
644 * access the file pointer through any of the sub-structs,
645 * or directly as just 'ki_filp' in this struct.
651 struct io_poll_iocb poll
;
652 struct io_accept accept
;
654 struct io_cancel cancel
;
655 struct io_timeout timeout
;
656 struct io_timeout_rem timeout_rem
;
657 struct io_connect connect
;
658 struct io_sr_msg sr_msg
;
660 struct io_close close
;
661 struct io_files_update files_update
;
662 struct io_fadvise fadvise
;
663 struct io_madvise madvise
;
664 struct io_epoll epoll
;
665 struct io_splice splice
;
666 struct io_provide_buf pbuf
;
667 struct io_statx statx
;
668 /* use only after cleaning per-op data, see io_clean_op() */
669 struct io_completion
compl;
672 /* opcode allocated if it needs to store data for async defer */
675 /* polled IO has completed */
681 struct io_ring_ctx
*ctx
;
684 struct task_struct
*task
;
687 struct list_head link_list
;
690 * 1. used with ctx->iopoll_list with reads/writes
691 * 2. to track reqs with ->files (see io_op_def::file_table)
693 struct list_head inflight_entry
;
695 struct percpu_ref
*fixed_file_refs
;
696 struct callback_head task_work
;
697 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
698 struct hlist_node hash_node
;
699 struct async_poll
*apoll
;
700 struct io_wq_work work
;
703 struct io_defer_entry
{
704 struct list_head list
;
705 struct io_kiocb
*req
;
709 #define IO_IOPOLL_BATCH 8
711 struct io_comp_state
{
713 struct list_head list
;
714 struct io_ring_ctx
*ctx
;
717 struct io_submit_state
{
718 struct blk_plug plug
;
721 * io_kiocb alloc cache
723 void *reqs
[IO_IOPOLL_BATCH
];
724 unsigned int free_reqs
;
727 * Batch completion logic
729 struct io_comp_state comp
;
732 * File reference cache
736 unsigned int has_refs
;
737 unsigned int ios_left
;
741 /* needs req->file assigned */
742 unsigned needs_file
: 1;
743 /* don't fail if file grab fails */
744 unsigned needs_file_no_error
: 1;
745 /* hash wq insertion if file is a regular file */
746 unsigned hash_reg_file
: 1;
747 /* unbound wq insertion if file is a non-regular file */
748 unsigned unbound_nonreg_file
: 1;
749 /* opcode is not supported by this kernel */
750 unsigned not_supported
: 1;
751 /* set if opcode supports polled "wait" */
753 unsigned pollout
: 1;
754 /* op supports buffer selection */
755 unsigned buffer_select
: 1;
756 /* must always have async data allocated */
757 unsigned needs_async_data
: 1;
758 /* size of async data needed, if any */
759 unsigned short async_size
;
763 static const struct io_op_def io_op_defs
[] = {
764 [IORING_OP_NOP
] = {},
765 [IORING_OP_READV
] = {
767 .unbound_nonreg_file
= 1,
770 .needs_async_data
= 1,
771 .async_size
= sizeof(struct io_async_rw
),
772 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
774 [IORING_OP_WRITEV
] = {
777 .unbound_nonreg_file
= 1,
779 .needs_async_data
= 1,
780 .async_size
= sizeof(struct io_async_rw
),
781 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
784 [IORING_OP_FSYNC
] = {
786 .work_flags
= IO_WQ_WORK_BLKCG
,
788 [IORING_OP_READ_FIXED
] = {
790 .unbound_nonreg_file
= 1,
792 .async_size
= sizeof(struct io_async_rw
),
793 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
795 [IORING_OP_WRITE_FIXED
] = {
798 .unbound_nonreg_file
= 1,
800 .async_size
= sizeof(struct io_async_rw
),
801 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
|
804 [IORING_OP_POLL_ADD
] = {
806 .unbound_nonreg_file
= 1,
808 [IORING_OP_POLL_REMOVE
] = {},
809 [IORING_OP_SYNC_FILE_RANGE
] = {
811 .work_flags
= IO_WQ_WORK_BLKCG
,
813 [IORING_OP_SENDMSG
] = {
815 .unbound_nonreg_file
= 1,
817 .needs_async_data
= 1,
818 .async_size
= sizeof(struct io_async_msghdr
),
819 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
822 [IORING_OP_RECVMSG
] = {
824 .unbound_nonreg_file
= 1,
827 .needs_async_data
= 1,
828 .async_size
= sizeof(struct io_async_msghdr
),
829 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
832 [IORING_OP_TIMEOUT
] = {
833 .needs_async_data
= 1,
834 .async_size
= sizeof(struct io_timeout_data
),
835 .work_flags
= IO_WQ_WORK_MM
,
837 [IORING_OP_TIMEOUT_REMOVE
] = {},
838 [IORING_OP_ACCEPT
] = {
840 .unbound_nonreg_file
= 1,
842 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
,
844 [IORING_OP_ASYNC_CANCEL
] = {},
845 [IORING_OP_LINK_TIMEOUT
] = {
846 .needs_async_data
= 1,
847 .async_size
= sizeof(struct io_timeout_data
),
848 .work_flags
= IO_WQ_WORK_MM
,
850 [IORING_OP_CONNECT
] = {
852 .unbound_nonreg_file
= 1,
854 .needs_async_data
= 1,
855 .async_size
= sizeof(struct io_async_connect
),
856 .work_flags
= IO_WQ_WORK_MM
,
858 [IORING_OP_FALLOCATE
] = {
860 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
,
862 [IORING_OP_OPENAT
] = {
863 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
|
866 [IORING_OP_CLOSE
] = {
868 .needs_file_no_error
= 1,
869 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
,
871 [IORING_OP_FILES_UPDATE
] = {
872 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
,
874 [IORING_OP_STATX
] = {
875 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
|
876 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
880 .unbound_nonreg_file
= 1,
883 .async_size
= sizeof(struct io_async_rw
),
884 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
886 [IORING_OP_WRITE
] = {
888 .unbound_nonreg_file
= 1,
890 .async_size
= sizeof(struct io_async_rw
),
891 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
894 [IORING_OP_FADVISE
] = {
896 .work_flags
= IO_WQ_WORK_BLKCG
,
898 [IORING_OP_MADVISE
] = {
899 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
903 .unbound_nonreg_file
= 1,
905 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
909 .unbound_nonreg_file
= 1,
912 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
914 [IORING_OP_OPENAT2
] = {
915 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_FS
|
918 [IORING_OP_EPOLL_CTL
] = {
919 .unbound_nonreg_file
= 1,
920 .work_flags
= IO_WQ_WORK_FILES
,
922 [IORING_OP_SPLICE
] = {
925 .unbound_nonreg_file
= 1,
926 .work_flags
= IO_WQ_WORK_BLKCG
,
928 [IORING_OP_PROVIDE_BUFFERS
] = {},
929 [IORING_OP_REMOVE_BUFFERS
] = {},
933 .unbound_nonreg_file
= 1,
937 enum io_mem_account
{
942 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
943 struct io_comp_state
*cs
);
944 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
945 static void io_put_req(struct io_kiocb
*req
);
946 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
947 static void io_double_put_req(struct io_kiocb
*req
);
948 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
949 static void __io_queue_linked_timeout(struct io_kiocb
*req
);
950 static void io_queue_linked_timeout(struct io_kiocb
*req
);
951 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
952 struct io_uring_files_update
*ip
,
954 static void __io_clean_op(struct io_kiocb
*req
);
955 static struct file
*io_file_get(struct io_submit_state
*state
,
956 struct io_kiocb
*req
, int fd
, bool fixed
);
957 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
);
958 static void io_file_put_work(struct work_struct
*work
);
960 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
961 struct iovec
**iovec
, struct iov_iter
*iter
,
963 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
964 const struct iovec
*fast_iov
,
965 struct iov_iter
*iter
, bool force
);
967 static struct kmem_cache
*req_cachep
;
969 static const struct file_operations io_uring_fops
;
971 struct sock
*io_uring_get_socket(struct file
*file
)
973 #if defined(CONFIG_UNIX)
974 if (file
->f_op
== &io_uring_fops
) {
975 struct io_ring_ctx
*ctx
= file
->private_data
;
977 return ctx
->ring_sock
->sk
;
982 EXPORT_SYMBOL(io_uring_get_socket
);
984 static inline void io_clean_op(struct io_kiocb
*req
)
986 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
|
991 static void io_sq_thread_drop_mm(void)
993 struct mm_struct
*mm
= current
->mm
;
996 kthread_unuse_mm(mm
);
1001 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
1004 if (unlikely(!(ctx
->flags
& IORING_SETUP_SQPOLL
) ||
1005 !ctx
->sqo_task
->mm
||
1006 !mmget_not_zero(ctx
->sqo_task
->mm
)))
1008 kthread_use_mm(ctx
->sqo_task
->mm
);
1014 static int io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
,
1015 struct io_kiocb
*req
)
1017 if (!(io_op_defs
[req
->opcode
].work_flags
& IO_WQ_WORK_MM
))
1019 return __io_sq_thread_acquire_mm(ctx
);
1022 static void io_sq_thread_associate_blkcg(struct io_ring_ctx
*ctx
,
1023 struct cgroup_subsys_state
**cur_css
)
1026 #ifdef CONFIG_BLK_CGROUP
1027 /* puts the old one when swapping */
1028 if (*cur_css
!= ctx
->sqo_blkcg_css
) {
1029 kthread_associate_blkcg(ctx
->sqo_blkcg_css
);
1030 *cur_css
= ctx
->sqo_blkcg_css
;
1035 static void io_sq_thread_unassociate_blkcg(void)
1037 #ifdef CONFIG_BLK_CGROUP
1038 kthread_associate_blkcg(NULL
);
1042 static inline void req_set_fail_links(struct io_kiocb
*req
)
1044 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1045 req
->flags
|= REQ_F_FAIL_LINK
;
1049 * None of these are dereferenced, they are simply used to check if any of
1050 * them have changed. If we're under current and check they are still the
1051 * same, we're fine to grab references to them for actual out-of-line use.
1053 static void io_init_identity(struct io_identity
*id
)
1055 id
->files
= current
->files
;
1056 id
->mm
= current
->mm
;
1057 #ifdef CONFIG_BLK_CGROUP
1059 id
->blkcg_css
= blkcg_css();
1062 id
->creds
= current_cred();
1063 id
->nsproxy
= current
->nsproxy
;
1064 id
->fs
= current
->fs
;
1065 id
->fsize
= rlimit(RLIMIT_FSIZE
);
1067 id
->loginuid
= current
->loginuid
;
1068 id
->sessionid
= current
->sessionid
;
1070 refcount_set(&id
->count
, 1);
1073 static inline void __io_req_init_async(struct io_kiocb
*req
)
1075 memset(&req
->work
, 0, sizeof(req
->work
));
1076 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1080 * Note: must call io_req_init_async() for the first time you
1081 * touch any members of io_wq_work.
1083 static inline void io_req_init_async(struct io_kiocb
*req
)
1085 struct io_uring_task
*tctx
= current
->io_uring
;
1087 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1090 __io_req_init_async(req
);
1092 /* Grab a ref if this isn't our static identity */
1093 req
->work
.identity
= tctx
->identity
;
1094 if (tctx
->identity
!= &tctx
->__identity
)
1095 refcount_inc(&req
->work
.identity
->count
);
1098 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
1100 return ctx
->flags
& IORING_SETUP_SQPOLL
;
1103 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1105 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1107 complete(&ctx
->ref_comp
);
1110 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1112 return !req
->timeout
.off
;
1115 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1117 struct io_ring_ctx
*ctx
;
1120 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1124 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
1125 if (!ctx
->fallback_req
)
1129 * Use 5 bits less than the max cq entries, that should give us around
1130 * 32 entries per hash list if totally full and uniformly spread.
1132 hash_bits
= ilog2(p
->cq_entries
);
1136 ctx
->cancel_hash_bits
= hash_bits
;
1137 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1139 if (!ctx
->cancel_hash
)
1141 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1143 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1144 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1147 ctx
->flags
= p
->flags
;
1148 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1149 INIT_LIST_HEAD(&ctx
->sqd_list
);
1150 init_waitqueue_head(&ctx
->cq_wait
);
1151 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1152 init_completion(&ctx
->ref_comp
);
1153 init_completion(&ctx
->sq_thread_comp
);
1154 idr_init(&ctx
->io_buffer_idr
);
1155 idr_init(&ctx
->personality_idr
);
1156 mutex_init(&ctx
->uring_lock
);
1157 init_waitqueue_head(&ctx
->wait
);
1158 spin_lock_init(&ctx
->completion_lock
);
1159 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1160 INIT_LIST_HEAD(&ctx
->defer_list
);
1161 INIT_LIST_HEAD(&ctx
->timeout_list
);
1162 init_waitqueue_head(&ctx
->inflight_wait
);
1163 spin_lock_init(&ctx
->inflight_lock
);
1164 INIT_LIST_HEAD(&ctx
->inflight_list
);
1165 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
1166 init_llist_head(&ctx
->file_put_llist
);
1169 if (ctx
->fallback_req
)
1170 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
1171 kfree(ctx
->cancel_hash
);
1176 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1178 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1179 struct io_ring_ctx
*ctx
= req
->ctx
;
1181 return seq
!= ctx
->cached_cq_tail
1182 + READ_ONCE(ctx
->cached_cq_overflow
);
1188 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1190 struct io_rings
*rings
= ctx
->rings
;
1192 /* order cqe stores with ring update */
1193 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1195 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1196 wake_up_interruptible(&ctx
->cq_wait
);
1197 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1201 static void io_put_identity(struct io_uring_task
*tctx
, struct io_kiocb
*req
)
1203 if (req
->work
.identity
== &tctx
->__identity
)
1205 if (refcount_dec_and_test(&req
->work
.identity
->count
))
1206 kfree(req
->work
.identity
);
1209 static void io_req_clean_work(struct io_kiocb
*req
)
1211 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1214 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1216 if (req
->work
.flags
& IO_WQ_WORK_MM
) {
1217 mmdrop(req
->work
.identity
->mm
);
1218 req
->work
.flags
&= ~IO_WQ_WORK_MM
;
1220 #ifdef CONFIG_BLK_CGROUP
1221 if (req
->work
.flags
& IO_WQ_WORK_BLKCG
) {
1222 css_put(req
->work
.identity
->blkcg_css
);
1223 req
->work
.flags
&= ~IO_WQ_WORK_BLKCG
;
1226 if (req
->work
.flags
& IO_WQ_WORK_CREDS
) {
1227 put_cred(req
->work
.identity
->creds
);
1228 req
->work
.flags
&= ~IO_WQ_WORK_CREDS
;
1230 if (req
->work
.flags
& IO_WQ_WORK_FS
) {
1231 struct fs_struct
*fs
= req
->work
.identity
->fs
;
1233 spin_lock(&req
->work
.identity
->fs
->lock
);
1236 spin_unlock(&req
->work
.identity
->fs
->lock
);
1239 req
->work
.flags
&= ~IO_WQ_WORK_FS
;
1242 io_put_identity(req
->task
->io_uring
, req
);
1246 * Create a private copy of io_identity, since some fields don't match
1247 * the current context.
1249 static bool io_identity_cow(struct io_kiocb
*req
)
1251 struct io_uring_task
*tctx
= current
->io_uring
;
1252 const struct cred
*creds
= NULL
;
1253 struct io_identity
*id
;
1255 if (req
->work
.flags
& IO_WQ_WORK_CREDS
)
1256 creds
= req
->work
.identity
->creds
;
1258 id
= kmemdup(req
->work
.identity
, sizeof(*id
), GFP_KERNEL
);
1259 if (unlikely(!id
)) {
1260 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1265 * We can safely just re-init the creds we copied Either the field
1266 * matches the current one, or we haven't grabbed it yet. The only
1267 * exception is ->creds, through registered personalities, so handle
1268 * that one separately.
1270 io_init_identity(id
);
1272 req
->work
.identity
->creds
= creds
;
1274 /* add one for this request */
1275 refcount_inc(&id
->count
);
1277 /* drop old identity, assign new one. one ref for req, one for tctx */
1278 if (req
->work
.identity
!= tctx
->identity
&&
1279 refcount_sub_and_test(2, &req
->work
.identity
->count
))
1280 kfree(req
->work
.identity
);
1282 req
->work
.identity
= id
;
1283 tctx
->identity
= id
;
1287 static bool io_grab_identity(struct io_kiocb
*req
)
1289 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1290 struct io_identity
*id
= req
->work
.identity
;
1291 struct io_ring_ctx
*ctx
= req
->ctx
;
1293 if (def
->work_flags
& IO_WQ_WORK_FSIZE
) {
1294 if (id
->fsize
!= rlimit(RLIMIT_FSIZE
))
1296 req
->work
.flags
|= IO_WQ_WORK_FSIZE
;
1299 if (!(req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1300 (def
->work_flags
& IO_WQ_WORK_FILES
) &&
1301 !(req
->flags
& REQ_F_NO_FILE_TABLE
)) {
1302 if (id
->files
!= current
->files
||
1303 id
->nsproxy
!= current
->nsproxy
)
1305 atomic_inc(&id
->files
->count
);
1306 get_nsproxy(id
->nsproxy
);
1307 req
->flags
|= REQ_F_INFLIGHT
;
1309 spin_lock_irq(&ctx
->inflight_lock
);
1310 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
1311 spin_unlock_irq(&ctx
->inflight_lock
);
1312 req
->work
.flags
|= IO_WQ_WORK_FILES
;
1314 #ifdef CONFIG_BLK_CGROUP
1315 if (!(req
->work
.flags
& IO_WQ_WORK_BLKCG
) &&
1316 (def
->work_flags
& IO_WQ_WORK_BLKCG
)) {
1318 if (id
->blkcg_css
!= blkcg_css()) {
1323 * This should be rare, either the cgroup is dying or the task
1324 * is moving cgroups. Just punt to root for the handful of ios.
1326 if (css_tryget_online(id
->blkcg_css
))
1327 req
->work
.flags
|= IO_WQ_WORK_BLKCG
;
1331 if (!(req
->work
.flags
& IO_WQ_WORK_CREDS
)) {
1332 if (id
->creds
!= current_cred())
1334 get_cred(id
->creds
);
1335 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
1338 if (!uid_eq(current
->loginuid
, id
->loginuid
) ||
1339 current
->sessionid
!= id
->sessionid
)
1342 if (!(req
->work
.flags
& IO_WQ_WORK_FS
) &&
1343 (def
->work_flags
& IO_WQ_WORK_FS
)) {
1344 if (current
->fs
!= id
->fs
)
1346 spin_lock(&id
->fs
->lock
);
1347 if (!id
->fs
->in_exec
) {
1349 req
->work
.flags
|= IO_WQ_WORK_FS
;
1351 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1353 spin_unlock(¤t
->fs
->lock
);
1359 static void io_prep_async_work(struct io_kiocb
*req
)
1361 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1362 struct io_ring_ctx
*ctx
= req
->ctx
;
1363 struct io_identity
*id
;
1365 io_req_init_async(req
);
1366 id
= req
->work
.identity
;
1368 if (req
->flags
& REQ_F_ISREG
) {
1369 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1370 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1372 if (def
->unbound_nonreg_file
)
1373 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1376 /* ->mm can never change on us */
1377 if (!(req
->work
.flags
& IO_WQ_WORK_MM
) &&
1378 (def
->work_flags
& IO_WQ_WORK_MM
)) {
1380 req
->work
.flags
|= IO_WQ_WORK_MM
;
1383 /* if we fail grabbing identity, we must COW, regrab, and retry */
1384 if (io_grab_identity(req
))
1387 if (!io_identity_cow(req
))
1390 /* can't fail at this point */
1391 if (!io_grab_identity(req
))
1395 static void io_prep_async_link(struct io_kiocb
*req
)
1397 struct io_kiocb
*cur
;
1399 io_prep_async_work(req
);
1400 if (req
->flags
& REQ_F_LINK_HEAD
)
1401 list_for_each_entry(cur
, &req
->link_list
, link_list
)
1402 io_prep_async_work(cur
);
1405 static struct io_kiocb
*__io_queue_async_work(struct io_kiocb
*req
)
1407 struct io_ring_ctx
*ctx
= req
->ctx
;
1408 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1410 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1411 &req
->work
, req
->flags
);
1412 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1416 static void io_queue_async_work(struct io_kiocb
*req
)
1418 struct io_kiocb
*link
;
1420 /* init ->work of the whole link before punting */
1421 io_prep_async_link(req
);
1422 link
= __io_queue_async_work(req
);
1425 io_queue_linked_timeout(link
);
1428 static void io_kill_timeout(struct io_kiocb
*req
)
1430 struct io_timeout_data
*io
= req
->async_data
;
1433 ret
= hrtimer_try_to_cancel(&io
->timer
);
1435 atomic_set(&req
->ctx
->cq_timeouts
,
1436 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1437 list_del_init(&req
->timeout
.list
);
1438 io_cqring_fill_event(req
, 0);
1439 io_put_req_deferred(req
, 1);
1443 static bool io_task_match(struct io_kiocb
*req
, struct task_struct
*tsk
)
1445 struct io_ring_ctx
*ctx
= req
->ctx
;
1447 if (!tsk
|| req
->task
== tsk
)
1449 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1450 if (ctx
->sq_data
&& req
->task
== ctx
->sq_data
->thread
)
1457 * Returns true if we found and killed one or more timeouts
1459 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
)
1461 struct io_kiocb
*req
, *tmp
;
1464 spin_lock_irq(&ctx
->completion_lock
);
1465 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
1466 if (io_task_match(req
, tsk
)) {
1467 io_kill_timeout(req
);
1471 spin_unlock_irq(&ctx
->completion_lock
);
1472 return canceled
!= 0;
1475 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1478 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1479 struct io_defer_entry
, list
);
1480 struct io_kiocb
*link
;
1482 if (req_need_defer(de
->req
, de
->seq
))
1484 list_del_init(&de
->list
);
1485 /* punt-init is done before queueing for defer */
1486 link
= __io_queue_async_work(de
->req
);
1488 __io_queue_linked_timeout(link
);
1489 /* drop submission reference */
1490 io_put_req_deferred(link
, 1);
1493 } while (!list_empty(&ctx
->defer_list
));
1496 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1498 while (!list_empty(&ctx
->timeout_list
)) {
1499 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1500 struct io_kiocb
, timeout
.list
);
1502 if (io_is_timeout_noseq(req
))
1504 if (req
->timeout
.target_seq
!= ctx
->cached_cq_tail
1505 - atomic_read(&ctx
->cq_timeouts
))
1508 list_del_init(&req
->timeout
.list
);
1509 io_kill_timeout(req
);
1513 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1515 io_flush_timeouts(ctx
);
1516 __io_commit_cqring(ctx
);
1518 if (unlikely(!list_empty(&ctx
->defer_list
)))
1519 __io_queue_deferred(ctx
);
1522 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1524 struct io_rings
*r
= ctx
->rings
;
1526 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1529 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1531 struct io_rings
*rings
= ctx
->rings
;
1534 tail
= ctx
->cached_cq_tail
;
1536 * writes to the cq entry need to come after reading head; the
1537 * control dependency is enough as we're using WRITE_ONCE to
1540 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1543 ctx
->cached_cq_tail
++;
1544 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1547 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1551 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1553 if (!ctx
->eventfd_async
)
1555 return io_wq_current_is_worker();
1558 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1560 if (waitqueue_active(&ctx
->wait
))
1561 wake_up(&ctx
->wait
);
1562 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1563 wake_up(&ctx
->sq_data
->wait
);
1564 if (io_should_trigger_evfd(ctx
))
1565 eventfd_signal(ctx
->cq_ev_fd
, 1);
1568 static void io_cqring_mark_overflow(struct io_ring_ctx
*ctx
)
1570 if (list_empty(&ctx
->cq_overflow_list
)) {
1571 clear_bit(0, &ctx
->sq_check_overflow
);
1572 clear_bit(0, &ctx
->cq_check_overflow
);
1573 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1577 static inline bool io_match_files(struct io_kiocb
*req
,
1578 struct files_struct
*files
)
1582 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
1583 (req
->work
.flags
& IO_WQ_WORK_FILES
))
1584 return req
->work
.identity
->files
== files
;
1588 /* Returns true if there are no backlogged entries after the flush */
1589 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1590 struct task_struct
*tsk
,
1591 struct files_struct
*files
)
1593 struct io_rings
*rings
= ctx
->rings
;
1594 struct io_kiocb
*req
, *tmp
;
1595 struct io_uring_cqe
*cqe
;
1596 unsigned long flags
;
1600 if (list_empty_careful(&ctx
->cq_overflow_list
))
1602 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1603 rings
->cq_ring_entries
))
1607 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1609 /* if force is set, the ring is going away. always drop after that */
1611 ctx
->cq_overflow_flushed
= 1;
1614 list_for_each_entry_safe(req
, tmp
, &ctx
->cq_overflow_list
, compl.list
) {
1615 if (tsk
&& req
->task
!= tsk
)
1617 if (!io_match_files(req
, files
))
1620 cqe
= io_get_cqring(ctx
);
1624 list_move(&req
->compl.list
, &list
);
1626 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1627 WRITE_ONCE(cqe
->res
, req
->result
);
1628 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1630 ctx
->cached_cq_overflow
++;
1631 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1632 ctx
->cached_cq_overflow
);
1636 io_commit_cqring(ctx
);
1637 io_cqring_mark_overflow(ctx
);
1639 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1640 io_cqring_ev_posted(ctx
);
1642 while (!list_empty(&list
)) {
1643 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1644 list_del(&req
->compl.list
);
1651 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1653 struct io_ring_ctx
*ctx
= req
->ctx
;
1654 struct io_uring_cqe
*cqe
;
1656 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1659 * If we can't get a cq entry, userspace overflowed the
1660 * submission (by quite a lot). Increment the overflow count in
1663 cqe
= io_get_cqring(ctx
);
1665 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1666 WRITE_ONCE(cqe
->res
, res
);
1667 WRITE_ONCE(cqe
->flags
, cflags
);
1668 } else if (ctx
->cq_overflow_flushed
|| req
->task
->io_uring
->in_idle
) {
1670 * If we're in ring overflow flush mode, or in task cancel mode,
1671 * then we cannot store the request for later flushing, we need
1672 * to drop it on the floor.
1674 ctx
->cached_cq_overflow
++;
1675 WRITE_ONCE(ctx
->rings
->cq_overflow
, ctx
->cached_cq_overflow
);
1677 if (list_empty(&ctx
->cq_overflow_list
)) {
1678 set_bit(0, &ctx
->sq_check_overflow
);
1679 set_bit(0, &ctx
->cq_check_overflow
);
1680 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1684 req
->compl.cflags
= cflags
;
1685 refcount_inc(&req
->refs
);
1686 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1690 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1692 __io_cqring_fill_event(req
, res
, 0);
1695 static void io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1697 struct io_ring_ctx
*ctx
= req
->ctx
;
1698 unsigned long flags
;
1700 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1701 __io_cqring_fill_event(req
, res
, cflags
);
1702 io_commit_cqring(ctx
);
1703 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1705 io_cqring_ev_posted(ctx
);
1708 static void io_submit_flush_completions(struct io_comp_state
*cs
)
1710 struct io_ring_ctx
*ctx
= cs
->ctx
;
1712 spin_lock_irq(&ctx
->completion_lock
);
1713 while (!list_empty(&cs
->list
)) {
1714 struct io_kiocb
*req
;
1716 req
= list_first_entry(&cs
->list
, struct io_kiocb
, compl.list
);
1717 list_del(&req
->compl.list
);
1718 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
1721 * io_free_req() doesn't care about completion_lock unless one
1722 * of these flags is set. REQ_F_WORK_INITIALIZED is in the list
1723 * because of a potential deadlock with req->work.fs->lock
1725 if (req
->flags
& (REQ_F_FAIL_LINK
|REQ_F_LINK_TIMEOUT
1726 |REQ_F_WORK_INITIALIZED
)) {
1727 spin_unlock_irq(&ctx
->completion_lock
);
1729 spin_lock_irq(&ctx
->completion_lock
);
1734 io_commit_cqring(ctx
);
1735 spin_unlock_irq(&ctx
->completion_lock
);
1737 io_cqring_ev_posted(ctx
);
1741 static void __io_req_complete(struct io_kiocb
*req
, long res
, unsigned cflags
,
1742 struct io_comp_state
*cs
)
1745 io_cqring_add_event(req
, res
, cflags
);
1750 req
->compl.cflags
= cflags
;
1751 list_add_tail(&req
->compl.list
, &cs
->list
);
1753 io_submit_flush_completions(cs
);
1757 static void io_req_complete(struct io_kiocb
*req
, long res
)
1759 __io_req_complete(req
, res
, 0, NULL
);
1762 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1764 return req
== (struct io_kiocb
*)
1765 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1768 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1770 struct io_kiocb
*req
;
1772 req
= ctx
->fallback_req
;
1773 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1779 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1780 struct io_submit_state
*state
)
1782 if (!state
->free_reqs
) {
1783 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1787 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1788 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1791 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1792 * retry single alloc to be on the safe side.
1794 if (unlikely(ret
<= 0)) {
1795 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1796 if (!state
->reqs
[0])
1800 state
->free_reqs
= ret
;
1804 return state
->reqs
[state
->free_reqs
];
1806 return io_get_fallback_req(ctx
);
1809 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1813 percpu_ref_put(req
->fixed_file_refs
);
1818 static void io_dismantle_req(struct io_kiocb
*req
)
1822 if (req
->async_data
)
1823 kfree(req
->async_data
);
1825 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1827 io_req_clean_work(req
);
1830 static void __io_free_req(struct io_kiocb
*req
)
1832 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1833 struct io_ring_ctx
*ctx
= req
->ctx
;
1835 io_dismantle_req(req
);
1837 percpu_counter_dec(&tctx
->inflight
);
1839 wake_up(&tctx
->wait
);
1840 put_task_struct(req
->task
);
1842 if (likely(!io_is_fallback_req(req
)))
1843 kmem_cache_free(req_cachep
, req
);
1845 clear_bit_unlock(0, (unsigned long *) &ctx
->fallback_req
);
1846 percpu_ref_put(&ctx
->refs
);
1849 static bool io_link_cancel_timeout(struct io_kiocb
*req
)
1851 struct io_timeout_data
*io
= req
->async_data
;
1852 struct io_ring_ctx
*ctx
= req
->ctx
;
1855 ret
= hrtimer_try_to_cancel(&io
->timer
);
1857 io_cqring_fill_event(req
, -ECANCELED
);
1858 io_commit_cqring(ctx
);
1859 req
->flags
&= ~REQ_F_LINK_HEAD
;
1860 io_put_req_deferred(req
, 1);
1867 static bool __io_kill_linked_timeout(struct io_kiocb
*req
)
1869 struct io_kiocb
*link
;
1872 if (list_empty(&req
->link_list
))
1874 link
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1875 if (link
->opcode
!= IORING_OP_LINK_TIMEOUT
)
1878 * Can happen if a linked timeout fired and link had been like
1879 * req -> link t-out -> link t-out [-> ...]
1881 if (!(link
->flags
& REQ_F_LTIMEOUT_ACTIVE
))
1884 list_del_init(&link
->link_list
);
1885 wake_ev
= io_link_cancel_timeout(link
);
1886 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1890 static void io_kill_linked_timeout(struct io_kiocb
*req
)
1892 struct io_ring_ctx
*ctx
= req
->ctx
;
1893 unsigned long flags
;
1896 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1897 wake_ev
= __io_kill_linked_timeout(req
);
1898 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1901 io_cqring_ev_posted(ctx
);
1904 static struct io_kiocb
*io_req_link_next(struct io_kiocb
*req
)
1906 struct io_kiocb
*nxt
;
1909 * The list should never be empty when we are called here. But could
1910 * potentially happen if the chain is messed up, check to be on the
1913 if (unlikely(list_empty(&req
->link_list
)))
1916 nxt
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1917 list_del_init(&req
->link_list
);
1918 if (!list_empty(&nxt
->link_list
))
1919 nxt
->flags
|= REQ_F_LINK_HEAD
;
1924 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
1926 static void io_fail_links(struct io_kiocb
*req
)
1928 struct io_ring_ctx
*ctx
= req
->ctx
;
1929 unsigned long flags
;
1931 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1932 while (!list_empty(&req
->link_list
)) {
1933 struct io_kiocb
*link
= list_first_entry(&req
->link_list
,
1934 struct io_kiocb
, link_list
);
1936 list_del_init(&link
->link_list
);
1937 trace_io_uring_fail_link(req
, link
);
1939 io_cqring_fill_event(link
, -ECANCELED
);
1942 * It's ok to free under spinlock as they're not linked anymore,
1943 * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
1946 if (link
->flags
& REQ_F_WORK_INITIALIZED
)
1947 io_put_req_deferred(link
, 2);
1949 io_double_put_req(link
);
1952 io_commit_cqring(ctx
);
1953 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1955 io_cqring_ev_posted(ctx
);
1958 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
1960 req
->flags
&= ~REQ_F_LINK_HEAD
;
1961 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
1962 io_kill_linked_timeout(req
);
1965 * If LINK is set, we have dependent requests in this chain. If we
1966 * didn't fail this request, queue the first one up, moving any other
1967 * dependencies to the next request. In case of failure, fail the rest
1970 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
)))
1971 return io_req_link_next(req
);
1976 static struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
1978 if (likely(!(req
->flags
& REQ_F_LINK_HEAD
)))
1980 return __io_req_find_next(req
);
1983 static int io_req_task_work_add(struct io_kiocb
*req
, bool twa_signal_ok
)
1985 struct task_struct
*tsk
= req
->task
;
1986 struct io_ring_ctx
*ctx
= req
->ctx
;
1987 enum task_work_notify_mode notify
;
1990 if (tsk
->flags
& PF_EXITING
)
1994 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
1995 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
1996 * processing task_work. There's no reliable way to tell if TWA_RESUME
2000 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
) && twa_signal_ok
)
2001 notify
= TWA_SIGNAL
;
2003 ret
= task_work_add(tsk
, &req
->task_work
, notify
);
2005 wake_up_process(tsk
);
2010 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
2012 struct io_ring_ctx
*ctx
= req
->ctx
;
2014 spin_lock_irq(&ctx
->completion_lock
);
2015 io_cqring_fill_event(req
, error
);
2016 io_commit_cqring(ctx
);
2017 spin_unlock_irq(&ctx
->completion_lock
);
2019 io_cqring_ev_posted(ctx
);
2020 req_set_fail_links(req
);
2021 io_double_put_req(req
);
2024 static void io_req_task_cancel(struct callback_head
*cb
)
2026 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2027 struct io_ring_ctx
*ctx
= req
->ctx
;
2029 __io_req_task_cancel(req
, -ECANCELED
);
2030 percpu_ref_put(&ctx
->refs
);
2033 static void __io_req_task_submit(struct io_kiocb
*req
)
2035 struct io_ring_ctx
*ctx
= req
->ctx
;
2037 if (!__io_sq_thread_acquire_mm(ctx
)) {
2038 mutex_lock(&ctx
->uring_lock
);
2039 __io_queue_sqe(req
, NULL
);
2040 mutex_unlock(&ctx
->uring_lock
);
2042 __io_req_task_cancel(req
, -EFAULT
);
2046 static void io_req_task_submit(struct callback_head
*cb
)
2048 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2049 struct io_ring_ctx
*ctx
= req
->ctx
;
2051 __io_req_task_submit(req
);
2052 percpu_ref_put(&ctx
->refs
);
2055 static void io_req_task_queue(struct io_kiocb
*req
)
2059 init_task_work(&req
->task_work
, io_req_task_submit
);
2060 percpu_ref_get(&req
->ctx
->refs
);
2062 ret
= io_req_task_work_add(req
, true);
2063 if (unlikely(ret
)) {
2064 struct task_struct
*tsk
;
2066 init_task_work(&req
->task_work
, io_req_task_cancel
);
2067 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2068 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2069 wake_up_process(tsk
);
2073 static void io_queue_next(struct io_kiocb
*req
)
2075 struct io_kiocb
*nxt
= io_req_find_next(req
);
2078 io_req_task_queue(nxt
);
2081 static void io_free_req(struct io_kiocb
*req
)
2088 void *reqs
[IO_IOPOLL_BATCH
];
2091 struct task_struct
*task
;
2095 static inline void io_init_req_batch(struct req_batch
*rb
)
2102 static void __io_req_free_batch_flush(struct io_ring_ctx
*ctx
,
2103 struct req_batch
*rb
)
2105 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
2106 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
2110 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2111 struct req_batch
*rb
)
2114 __io_req_free_batch_flush(ctx
, rb
);
2116 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2118 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2119 put_task_struct_many(rb
->task
, rb
->task_refs
);
2124 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
)
2126 if (unlikely(io_is_fallback_req(req
))) {
2130 if (req
->flags
& REQ_F_LINK_HEAD
)
2133 if (req
->task
!= rb
->task
) {
2135 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2137 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2138 put_task_struct_many(rb
->task
, rb
->task_refs
);
2140 rb
->task
= req
->task
;
2145 io_dismantle_req(req
);
2146 rb
->reqs
[rb
->to_free
++] = req
;
2147 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
2148 __io_req_free_batch_flush(req
->ctx
, rb
);
2152 * Drop reference to request, return next in chain (if there is one) if this
2153 * was the last reference to this request.
2155 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2157 struct io_kiocb
*nxt
= NULL
;
2159 if (refcount_dec_and_test(&req
->refs
)) {
2160 nxt
= io_req_find_next(req
);
2166 static void io_put_req(struct io_kiocb
*req
)
2168 if (refcount_dec_and_test(&req
->refs
))
2172 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2174 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2179 static void io_free_req_deferred(struct io_kiocb
*req
)
2183 init_task_work(&req
->task_work
, io_put_req_deferred_cb
);
2184 ret
= io_req_task_work_add(req
, true);
2185 if (unlikely(ret
)) {
2186 struct task_struct
*tsk
;
2188 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2189 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2190 wake_up_process(tsk
);
2194 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2196 if (refcount_sub_and_test(refs
, &req
->refs
))
2197 io_free_req_deferred(req
);
2200 static struct io_wq_work
*io_steal_work(struct io_kiocb
*req
)
2202 struct io_kiocb
*nxt
;
2205 * A ref is owned by io-wq in which context we're. So, if that's the
2206 * last one, it's safe to steal next work. False negatives are Ok,
2207 * it just will be re-punted async in io_put_work()
2209 if (refcount_read(&req
->refs
) != 1)
2212 nxt
= io_req_find_next(req
);
2213 return nxt
? &nxt
->work
: NULL
;
2216 static void io_double_put_req(struct io_kiocb
*req
)
2218 /* drop both submit and complete references */
2219 if (refcount_sub_and_test(2, &req
->refs
))
2223 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
2225 struct io_rings
*rings
= ctx
->rings
;
2227 if (test_bit(0, &ctx
->cq_check_overflow
)) {
2229 * noflush == true is from the waitqueue handler, just ensure
2230 * we wake up the task, and the next invocation will flush the
2231 * entries. We cannot safely to it from here.
2233 if (noflush
&& !list_empty(&ctx
->cq_overflow_list
))
2236 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
2239 /* See comment at the top of this file */
2241 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
2244 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2246 struct io_rings
*rings
= ctx
->rings
;
2248 /* make sure SQ entry isn't read before tail */
2249 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2252 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2254 unsigned int cflags
;
2256 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2257 cflags
|= IORING_CQE_F_BUFFER
;
2258 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2263 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2265 struct io_buffer
*kbuf
;
2267 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2268 return io_put_kbuf(req
, kbuf
);
2271 static inline bool io_run_task_work(void)
2274 * Not safe to run on exiting task, and the task_work handling will
2275 * not add work to such a task.
2277 if (unlikely(current
->flags
& PF_EXITING
))
2279 if (current
->task_works
) {
2280 __set_current_state(TASK_RUNNING
);
2288 static void io_iopoll_queue(struct list_head
*again
)
2290 struct io_kiocb
*req
;
2293 req
= list_first_entry(again
, struct io_kiocb
, inflight_entry
);
2294 list_del(&req
->inflight_entry
);
2295 __io_complete_rw(req
, -EAGAIN
, 0, NULL
);
2296 } while (!list_empty(again
));
2300 * Find and free completed poll iocbs
2302 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2303 struct list_head
*done
)
2305 struct req_batch rb
;
2306 struct io_kiocb
*req
;
2309 /* order with ->result store in io_complete_rw_iopoll() */
2312 io_init_req_batch(&rb
);
2313 while (!list_empty(done
)) {
2316 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2317 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2319 req
->iopoll_completed
= 0;
2320 list_move_tail(&req
->inflight_entry
, &again
);
2323 list_del(&req
->inflight_entry
);
2325 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2326 cflags
= io_put_rw_kbuf(req
);
2328 __io_cqring_fill_event(req
, req
->result
, cflags
);
2331 if (refcount_dec_and_test(&req
->refs
))
2332 io_req_free_batch(&rb
, req
);
2335 io_commit_cqring(ctx
);
2336 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
2337 io_cqring_ev_posted(ctx
);
2338 io_req_free_batch_finish(ctx
, &rb
);
2340 if (!list_empty(&again
))
2341 io_iopoll_queue(&again
);
2344 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2347 struct io_kiocb
*req
, *tmp
;
2353 * Only spin for completions if we don't have multiple devices hanging
2354 * off our complete list, and we're under the requested amount.
2356 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2359 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2360 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2363 * Move completed and retryable entries to our local lists.
2364 * If we find a request that requires polling, break out
2365 * and complete those lists first, if we have entries there.
2367 if (READ_ONCE(req
->iopoll_completed
)) {
2368 list_move_tail(&req
->inflight_entry
, &done
);
2371 if (!list_empty(&done
))
2374 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2378 /* iopoll may have completed current req */
2379 if (READ_ONCE(req
->iopoll_completed
))
2380 list_move_tail(&req
->inflight_entry
, &done
);
2387 if (!list_empty(&done
))
2388 io_iopoll_complete(ctx
, nr_events
, &done
);
2394 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2395 * non-spinning poll check - we'll still enter the driver poll loop, but only
2396 * as a non-spinning completion check.
2398 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2401 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2404 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2407 if (*nr_events
>= min
)
2415 * We can't just wait for polled events to come to us, we have to actively
2416 * find and complete them.
2418 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2420 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2423 mutex_lock(&ctx
->uring_lock
);
2424 while (!list_empty(&ctx
->iopoll_list
)) {
2425 unsigned int nr_events
= 0;
2427 io_do_iopoll(ctx
, &nr_events
, 0);
2429 /* let it sleep and repeat later if can't complete a request */
2433 * Ensure we allow local-to-the-cpu processing to take place,
2434 * in this case we need to ensure that we reap all events.
2435 * Also let task_work, etc. to progress by releasing the mutex
2437 if (need_resched()) {
2438 mutex_unlock(&ctx
->uring_lock
);
2440 mutex_lock(&ctx
->uring_lock
);
2443 mutex_unlock(&ctx
->uring_lock
);
2446 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2448 unsigned int nr_events
= 0;
2449 int iters
= 0, ret
= 0;
2452 * We disallow the app entering submit/complete with polling, but we
2453 * still need to lock the ring to prevent racing with polled issue
2454 * that got punted to a workqueue.
2456 mutex_lock(&ctx
->uring_lock
);
2459 * Don't enter poll loop if we already have events pending.
2460 * If we do, we can potentially be spinning for commands that
2461 * already triggered a CQE (eg in error).
2463 if (io_cqring_events(ctx
, false))
2467 * If a submit got punted to a workqueue, we can have the
2468 * application entering polling for a command before it gets
2469 * issued. That app will hold the uring_lock for the duration
2470 * of the poll right here, so we need to take a breather every
2471 * now and then to ensure that the issue has a chance to add
2472 * the poll to the issued list. Otherwise we can spin here
2473 * forever, while the workqueue is stuck trying to acquire the
2476 if (!(++iters
& 7)) {
2477 mutex_unlock(&ctx
->uring_lock
);
2479 mutex_lock(&ctx
->uring_lock
);
2482 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2486 } while (min
&& !nr_events
&& !need_resched());
2488 mutex_unlock(&ctx
->uring_lock
);
2492 static void kiocb_end_write(struct io_kiocb
*req
)
2495 * Tell lockdep we inherited freeze protection from submission
2498 if (req
->flags
& REQ_F_ISREG
) {
2499 struct inode
*inode
= file_inode(req
->file
);
2501 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2503 file_end_write(req
->file
);
2506 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
,
2507 struct io_comp_state
*cs
)
2509 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2512 if (kiocb
->ki_flags
& IOCB_WRITE
)
2513 kiocb_end_write(req
);
2515 if (res
!= req
->result
)
2516 req_set_fail_links(req
);
2517 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2518 cflags
= io_put_rw_kbuf(req
);
2519 __io_req_complete(req
, res
, cflags
, cs
);
2523 static bool io_resubmit_prep(struct io_kiocb
*req
, int error
)
2525 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2526 ssize_t ret
= -ECANCELED
;
2527 struct iov_iter iter
;
2535 switch (req
->opcode
) {
2536 case IORING_OP_READV
:
2537 case IORING_OP_READ_FIXED
:
2538 case IORING_OP_READ
:
2541 case IORING_OP_WRITEV
:
2542 case IORING_OP_WRITE_FIXED
:
2543 case IORING_OP_WRITE
:
2547 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2552 if (!req
->async_data
) {
2553 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2556 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, &iter
, false);
2564 req_set_fail_links(req
);
2565 io_req_complete(req
, ret
);
2570 static bool io_rw_reissue(struct io_kiocb
*req
, long res
)
2573 umode_t mode
= file_inode(req
->file
)->i_mode
;
2576 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2578 if ((res
!= -EAGAIN
&& res
!= -EOPNOTSUPP
) || io_wq_current_is_worker())
2581 ret
= io_sq_thread_acquire_mm(req
->ctx
, req
);
2583 if (io_resubmit_prep(req
, ret
)) {
2584 refcount_inc(&req
->refs
);
2585 io_queue_async_work(req
);
2593 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2594 struct io_comp_state
*cs
)
2596 if (!io_rw_reissue(req
, res
))
2597 io_complete_rw_common(&req
->rw
.kiocb
, res
, cs
);
2600 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2602 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2604 __io_complete_rw(req
, res
, res2
, NULL
);
2607 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2609 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2611 if (kiocb
->ki_flags
& IOCB_WRITE
)
2612 kiocb_end_write(req
);
2614 if (res
!= -EAGAIN
&& res
!= req
->result
)
2615 req_set_fail_links(req
);
2617 WRITE_ONCE(req
->result
, res
);
2618 /* order with io_poll_complete() checking ->result */
2620 WRITE_ONCE(req
->iopoll_completed
, 1);
2624 * After the iocb has been issued, it's safe to be found on the poll list.
2625 * Adding the kiocb to the list AFTER submission ensures that we don't
2626 * find it from a io_iopoll_getevents() thread before the issuer is done
2627 * accessing the kiocb cookie.
2629 static void io_iopoll_req_issued(struct io_kiocb
*req
)
2631 struct io_ring_ctx
*ctx
= req
->ctx
;
2634 * Track whether we have multiple files in our lists. This will impact
2635 * how we do polling eventually, not spinning if we're on potentially
2636 * different devices.
2638 if (list_empty(&ctx
->iopoll_list
)) {
2639 ctx
->poll_multi_file
= false;
2640 } else if (!ctx
->poll_multi_file
) {
2641 struct io_kiocb
*list_req
;
2643 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2645 if (list_req
->file
!= req
->file
)
2646 ctx
->poll_multi_file
= true;
2650 * For fast devices, IO may have already completed. If it has, add
2651 * it to the front so we find it first.
2653 if (READ_ONCE(req
->iopoll_completed
))
2654 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2656 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2658 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2659 wq_has_sleeper(&ctx
->sq_data
->wait
))
2660 wake_up(&ctx
->sq_data
->wait
);
2663 static void __io_state_file_put(struct io_submit_state
*state
)
2665 if (state
->has_refs
)
2666 fput_many(state
->file
, state
->has_refs
);
2670 static inline void io_state_file_put(struct io_submit_state
*state
)
2673 __io_state_file_put(state
);
2677 * Get as many references to a file as we have IOs left in this submission,
2678 * assuming most submissions are for one file, or at least that each file
2679 * has more than one submission.
2681 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2687 if (state
->fd
== fd
) {
2691 __io_state_file_put(state
);
2693 state
->file
= fget_many(fd
, state
->ios_left
);
2698 state
->has_refs
= state
->ios_left
- 1;
2702 static bool io_bdev_nowait(struct block_device
*bdev
)
2705 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2712 * If we tracked the file through the SCM inflight mechanism, we could support
2713 * any file. For now, just ensure that anything potentially problematic is done
2716 static bool io_file_supports_async(struct file
*file
, int rw
)
2718 umode_t mode
= file_inode(file
)->i_mode
;
2720 if (S_ISBLK(mode
)) {
2721 if (io_bdev_nowait(file
->f_inode
->i_bdev
))
2725 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2727 if (S_ISREG(mode
)) {
2728 if (io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2729 file
->f_op
!= &io_uring_fops
)
2734 /* any ->read/write should understand O_NONBLOCK */
2735 if (file
->f_flags
& O_NONBLOCK
)
2738 if (!(file
->f_mode
& FMODE_NOWAIT
))
2742 return file
->f_op
->read_iter
!= NULL
;
2744 return file
->f_op
->write_iter
!= NULL
;
2747 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2749 struct io_ring_ctx
*ctx
= req
->ctx
;
2750 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2754 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2755 req
->flags
|= REQ_F_ISREG
;
2757 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2758 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2759 req
->flags
|= REQ_F_CUR_POS
;
2760 kiocb
->ki_pos
= req
->file
->f_pos
;
2762 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2763 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2764 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2768 ioprio
= READ_ONCE(sqe
->ioprio
);
2770 ret
= ioprio_check_cap(ioprio
);
2774 kiocb
->ki_ioprio
= ioprio
;
2776 kiocb
->ki_ioprio
= get_current_ioprio();
2778 /* don't allow async punt if RWF_NOWAIT was requested */
2779 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2780 req
->flags
|= REQ_F_NOWAIT
;
2782 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2783 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2784 !kiocb
->ki_filp
->f_op
->iopoll
)
2787 kiocb
->ki_flags
|= IOCB_HIPRI
;
2788 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2789 req
->iopoll_completed
= 0;
2791 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2793 kiocb
->ki_complete
= io_complete_rw
;
2796 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2797 req
->rw
.len
= READ_ONCE(sqe
->len
);
2798 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2802 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2808 case -ERESTARTNOINTR
:
2809 case -ERESTARTNOHAND
:
2810 case -ERESTART_RESTARTBLOCK
:
2812 * We can't just restart the syscall, since previously
2813 * submitted sqes may already be in progress. Just fail this
2819 kiocb
->ki_complete(kiocb
, ret
, 0);
2823 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2824 struct io_comp_state
*cs
)
2826 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2827 struct io_async_rw
*io
= req
->async_data
;
2829 /* add previously done IO, if any */
2830 if (io
&& io
->bytes_done
> 0) {
2832 ret
= io
->bytes_done
;
2834 ret
+= io
->bytes_done
;
2837 if (req
->flags
& REQ_F_CUR_POS
)
2838 req
->file
->f_pos
= kiocb
->ki_pos
;
2839 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2840 __io_complete_rw(req
, ret
, 0, cs
);
2842 io_rw_done(kiocb
, ret
);
2845 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2846 struct iov_iter
*iter
)
2848 struct io_ring_ctx
*ctx
= req
->ctx
;
2849 size_t len
= req
->rw
.len
;
2850 struct io_mapped_ubuf
*imu
;
2851 u16 index
, buf_index
= req
->buf_index
;
2855 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2857 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2858 imu
= &ctx
->user_bufs
[index
];
2859 buf_addr
= req
->rw
.addr
;
2862 if (buf_addr
+ len
< buf_addr
)
2864 /* not inside the mapped region */
2865 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2869 * May not be a start of buffer, set size appropriately
2870 * and advance us to the beginning.
2872 offset
= buf_addr
- imu
->ubuf
;
2873 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2877 * Don't use iov_iter_advance() here, as it's really slow for
2878 * using the latter parts of a big fixed buffer - it iterates
2879 * over each segment manually. We can cheat a bit here, because
2882 * 1) it's a BVEC iter, we set it up
2883 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2884 * first and last bvec
2886 * So just find our index, and adjust the iterator afterwards.
2887 * If the offset is within the first bvec (or the whole first
2888 * bvec, just use iov_iter_advance(). This makes it easier
2889 * since we can just skip the first segment, which may not
2890 * be PAGE_SIZE aligned.
2892 const struct bio_vec
*bvec
= imu
->bvec
;
2894 if (offset
<= bvec
->bv_len
) {
2895 iov_iter_advance(iter
, offset
);
2897 unsigned long seg_skip
;
2899 /* skip first vec */
2900 offset
-= bvec
->bv_len
;
2901 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2903 iter
->bvec
= bvec
+ seg_skip
;
2904 iter
->nr_segs
-= seg_skip
;
2905 iter
->count
-= bvec
->bv_len
+ offset
;
2906 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2913 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2916 mutex_unlock(&ctx
->uring_lock
);
2919 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2922 * "Normal" inline submissions always hold the uring_lock, since we
2923 * grab it from the system call. Same is true for the SQPOLL offload.
2924 * The only exception is when we've detached the request and issue it
2925 * from an async worker thread, grab the lock for that case.
2928 mutex_lock(&ctx
->uring_lock
);
2931 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2932 int bgid
, struct io_buffer
*kbuf
,
2935 struct io_buffer
*head
;
2937 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2940 io_ring_submit_lock(req
->ctx
, needs_lock
);
2942 lockdep_assert_held(&req
->ctx
->uring_lock
);
2944 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
2946 if (!list_empty(&head
->list
)) {
2947 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2949 list_del(&kbuf
->list
);
2952 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
2954 if (*len
> kbuf
->len
)
2957 kbuf
= ERR_PTR(-ENOBUFS
);
2960 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2965 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2968 struct io_buffer
*kbuf
;
2971 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2972 bgid
= req
->buf_index
;
2973 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2976 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2977 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2978 return u64_to_user_ptr(kbuf
->addr
);
2981 #ifdef CONFIG_COMPAT
2982 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2985 struct compat_iovec __user
*uiov
;
2986 compat_ssize_t clen
;
2990 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2991 if (!access_ok(uiov
, sizeof(*uiov
)))
2993 if (__get_user(clen
, &uiov
->iov_len
))
2999 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3001 return PTR_ERR(buf
);
3002 iov
[0].iov_base
= buf
;
3003 iov
[0].iov_len
= (compat_size_t
) len
;
3008 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3011 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
3015 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3018 len
= iov
[0].iov_len
;
3021 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3023 return PTR_ERR(buf
);
3024 iov
[0].iov_base
= buf
;
3025 iov
[0].iov_len
= len
;
3029 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3032 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3033 struct io_buffer
*kbuf
;
3035 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3036 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3037 iov
[0].iov_len
= kbuf
->len
;
3042 else if (req
->rw
.len
> 1)
3045 #ifdef CONFIG_COMPAT
3046 if (req
->ctx
->compat
)
3047 return io_compat_import(req
, iov
, needs_lock
);
3050 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3053 static ssize_t
__io_import_iovec(int rw
, struct io_kiocb
*req
,
3054 struct iovec
**iovec
, struct iov_iter
*iter
,
3057 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3058 size_t sqe_len
= req
->rw
.len
;
3062 opcode
= req
->opcode
;
3063 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3065 return io_import_fixed(req
, rw
, iter
);
3068 /* buffer index only valid with fixed read/write, or buffer select */
3069 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3072 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3073 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3074 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3076 return PTR_ERR(buf
);
3077 req
->rw
.len
= sqe_len
;
3080 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3082 return ret
< 0 ? ret
: sqe_len
;
3085 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3086 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3088 ret
= (*iovec
)->iov_len
;
3089 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
3095 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3099 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
3100 struct iovec
**iovec
, struct iov_iter
*iter
,
3103 struct io_async_rw
*iorw
= req
->async_data
;
3106 return __io_import_iovec(rw
, req
, iovec
, iter
, needs_lock
);
3108 return iov_iter_count(&iorw
->iter
);
3111 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3113 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3117 * For files that don't have ->read_iter() and ->write_iter(), handle them
3118 * by looping over ->read() or ->write() manually.
3120 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3122 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3123 struct file
*file
= req
->file
;
3127 * Don't support polled IO through this interface, and we can't
3128 * support non-blocking either. For the latter, this just causes
3129 * the kiocb to be handled from an async context.
3131 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3133 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3136 while (iov_iter_count(iter
)) {
3140 if (!iov_iter_is_bvec(iter
)) {
3141 iovec
= iov_iter_iovec(iter
);
3143 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3144 iovec
.iov_len
= req
->rw
.len
;
3148 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3149 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3151 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3152 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3161 if (nr
!= iovec
.iov_len
)
3165 iov_iter_advance(iter
, nr
);
3171 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3172 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3174 struct io_async_rw
*rw
= req
->async_data
;
3176 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3177 rw
->free_iovec
= iovec
;
3179 /* can only be fixed buffers, no need to do anything */
3180 if (iter
->type
== ITER_BVEC
)
3183 unsigned iov_off
= 0;
3185 rw
->iter
.iov
= rw
->fast_iov
;
3186 if (iter
->iov
!= fast_iov
) {
3187 iov_off
= iter
->iov
- fast_iov
;
3188 rw
->iter
.iov
+= iov_off
;
3190 if (rw
->fast_iov
!= fast_iov
)
3191 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3192 sizeof(struct iovec
) * iter
->nr_segs
);
3194 req
->flags
|= REQ_F_NEED_CLEANUP
;
3198 static inline int __io_alloc_async_data(struct io_kiocb
*req
)
3200 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3201 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3202 return req
->async_data
== NULL
;
3205 static int io_alloc_async_data(struct io_kiocb
*req
)
3207 if (!io_op_defs
[req
->opcode
].needs_async_data
)
3210 return __io_alloc_async_data(req
);
3213 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3214 const struct iovec
*fast_iov
,
3215 struct iov_iter
*iter
, bool force
)
3217 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_data
)
3219 if (!req
->async_data
) {
3220 if (__io_alloc_async_data(req
))
3223 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3228 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3230 struct io_async_rw
*iorw
= req
->async_data
;
3231 struct iovec
*iov
= iorw
->fast_iov
;
3234 ret
= __io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3235 if (unlikely(ret
< 0))
3238 iorw
->bytes_done
= 0;
3239 iorw
->free_iovec
= iov
;
3241 req
->flags
|= REQ_F_NEED_CLEANUP
;
3245 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3249 ret
= io_prep_rw(req
, sqe
);
3253 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3256 /* either don't need iovec imported or already have it */
3257 if (!req
->async_data
)
3259 return io_rw_prep_async(req
, READ
);
3263 * This is our waitqueue callback handler, registered through lock_page_async()
3264 * when we initially tried to do the IO with the iocb armed our waitqueue.
3265 * This gets called when the page is unlocked, and we generally expect that to
3266 * happen when the page IO is completed and the page is now uptodate. This will
3267 * queue a task_work based retry of the operation, attempting to copy the data
3268 * again. If the latter fails because the page was NOT uptodate, then we will
3269 * do a thread based blocking retry of the operation. That's the unexpected
3272 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3273 int sync
, void *arg
)
3275 struct wait_page_queue
*wpq
;
3276 struct io_kiocb
*req
= wait
->private;
3277 struct wait_page_key
*key
= arg
;
3280 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3282 if (!wake_page_match(wpq
, key
))
3285 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3286 list_del_init(&wait
->entry
);
3288 init_task_work(&req
->task_work
, io_req_task_submit
);
3289 percpu_ref_get(&req
->ctx
->refs
);
3291 /* submit ref gets dropped, acquire a new one */
3292 refcount_inc(&req
->refs
);
3293 ret
= io_req_task_work_add(req
, true);
3294 if (unlikely(ret
)) {
3295 struct task_struct
*tsk
;
3297 /* queue just for cancelation */
3298 init_task_work(&req
->task_work
, io_req_task_cancel
);
3299 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
3300 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
3301 wake_up_process(tsk
);
3307 * This controls whether a given IO request should be armed for async page
3308 * based retry. If we return false here, the request is handed to the async
3309 * worker threads for retry. If we're doing buffered reads on a regular file,
3310 * we prepare a private wait_page_queue entry and retry the operation. This
3311 * will either succeed because the page is now uptodate and unlocked, or it
3312 * will register a callback when the page is unlocked at IO completion. Through
3313 * that callback, io_uring uses task_work to setup a retry of the operation.
3314 * That retry will attempt the buffered read again. The retry will generally
3315 * succeed, or in rare cases where it fails, we then fall back to using the
3316 * async worker threads for a blocking retry.
3318 static bool io_rw_should_retry(struct io_kiocb
*req
)
3320 struct io_async_rw
*rw
= req
->async_data
;
3321 struct wait_page_queue
*wait
= &rw
->wpq
;
3322 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3324 /* never retry for NOWAIT, we just complete with -EAGAIN */
3325 if (req
->flags
& REQ_F_NOWAIT
)
3328 /* Only for buffered IO */
3329 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3333 * just use poll if we can, and don't attempt if the fs doesn't
3334 * support callback based unlocks
3336 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3339 wait
->wait
.func
= io_async_buf_func
;
3340 wait
->wait
.private = req
;
3341 wait
->wait
.flags
= 0;
3342 INIT_LIST_HEAD(&wait
->wait
.entry
);
3343 kiocb
->ki_flags
|= IOCB_WAITQ
;
3344 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3345 kiocb
->ki_waitq
= wait
;
3349 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3351 if (req
->file
->f_op
->read_iter
)
3352 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3353 else if (req
->file
->f_op
->read
)
3354 return loop_rw_iter(READ
, req
, iter
);
3359 static int io_read(struct io_kiocb
*req
, bool force_nonblock
,
3360 struct io_comp_state
*cs
)
3362 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3363 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3364 struct iov_iter __iter
, *iter
= &__iter
;
3365 struct io_async_rw
*rw
= req
->async_data
;
3366 ssize_t io_size
, ret
, ret2
;
3373 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3376 iov_count
= iov_iter_count(iter
);
3378 req
->result
= io_size
;
3381 /* Ensure we clear previously set non-block flag */
3382 if (!force_nonblock
)
3383 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3385 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3388 /* If the file doesn't support async, just async punt */
3389 no_async
= force_nonblock
&& !io_file_supports_async(req
->file
, READ
);
3393 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), iov_count
);
3397 ret
= io_iter_do_read(req
, iter
);
3401 } else if (ret
== -EIOCBQUEUED
) {
3404 } else if (ret
== -EAGAIN
) {
3405 /* IOPOLL retry should happen for io-wq threads */
3406 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3408 /* no retry on NONBLOCK marked file */
3409 if (req
->file
->f_flags
& O_NONBLOCK
)
3411 /* some cases will consume bytes even on error returns */
3412 iov_iter_revert(iter
, iov_count
- iov_iter_count(iter
));
3415 } else if (ret
< 0) {
3416 /* make sure -ERESTARTSYS -> -EINTR is done */
3420 /* read it all, or we did blocking attempt. no retry. */
3421 if (!iov_iter_count(iter
) || !force_nonblock
||
3422 (req
->file
->f_flags
& O_NONBLOCK
))
3427 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3434 rw
= req
->async_data
;
3435 /* it's copied and will be cleaned with ->io */
3437 /* now use our persistent iterator, if we aren't already */
3440 rw
->bytes_done
+= ret
;
3441 /* if we can retry, do so with the callbacks armed */
3442 if (!io_rw_should_retry(req
)) {
3443 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3448 * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
3449 * get -EIOCBQUEUED, then we'll get a notification when the desired
3450 * page gets unlocked. We can also get a partial read here, and if we
3451 * do, then just retry at the new offset.
3453 ret
= io_iter_do_read(req
, iter
);
3454 if (ret
== -EIOCBQUEUED
) {
3457 } else if (ret
> 0 && ret
< io_size
) {
3458 /* we got some bytes, but not all. retry. */
3462 kiocb_done(kiocb
, ret
, cs
);
3465 /* it's reportedly faster than delegating the null check to kfree() */
3471 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3475 ret
= io_prep_rw(req
, sqe
);
3479 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3482 /* either don't need iovec imported or already have it */
3483 if (!req
->async_data
)
3485 return io_rw_prep_async(req
, WRITE
);
3488 static int io_write(struct io_kiocb
*req
, bool force_nonblock
,
3489 struct io_comp_state
*cs
)
3491 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3492 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3493 struct iov_iter __iter
, *iter
= &__iter
;
3494 struct io_async_rw
*rw
= req
->async_data
;
3496 ssize_t ret
, ret2
, io_size
;
3501 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3504 iov_count
= iov_iter_count(iter
);
3506 req
->result
= io_size
;
3508 /* Ensure we clear previously set non-block flag */
3509 if (!force_nonblock
)
3510 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3512 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3514 /* If the file doesn't support async, just async punt */
3515 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3518 /* file path doesn't support NOWAIT for non-direct_IO */
3519 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3520 (req
->flags
& REQ_F_ISREG
))
3523 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), iov_count
);
3528 * Open-code file_start_write here to grab freeze protection,
3529 * which will be released by another thread in
3530 * io_complete_rw(). Fool lockdep by telling it the lock got
3531 * released so that it doesn't complain about the held lock when
3532 * we return to userspace.
3534 if (req
->flags
& REQ_F_ISREG
) {
3535 __sb_start_write(file_inode(req
->file
)->i_sb
,
3536 SB_FREEZE_WRITE
, true);
3537 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3540 kiocb
->ki_flags
|= IOCB_WRITE
;
3542 if (req
->file
->f_op
->write_iter
)
3543 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3544 else if (req
->file
->f_op
->write
)
3545 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3550 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3551 * retry them without IOCB_NOWAIT.
3553 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3555 /* no retry on NONBLOCK marked file */
3556 if (ret2
== -EAGAIN
&& (req
->file
->f_flags
& O_NONBLOCK
))
3558 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3559 /* IOPOLL retry should happen for io-wq threads */
3560 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3563 kiocb_done(kiocb
, ret2
, cs
);
3566 /* some cases will consume bytes even on error returns */
3567 iov_iter_revert(iter
, iov_count
- iov_iter_count(iter
));
3568 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3573 /* it's reportedly faster than delegating the null check to kfree() */
3579 static int __io_splice_prep(struct io_kiocb
*req
,
3580 const struct io_uring_sqe
*sqe
)
3582 struct io_splice
* sp
= &req
->splice
;
3583 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3585 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3589 sp
->len
= READ_ONCE(sqe
->len
);
3590 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3592 if (unlikely(sp
->flags
& ~valid_flags
))
3595 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3596 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3599 req
->flags
|= REQ_F_NEED_CLEANUP
;
3601 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3603 * Splice operation will be punted aync, and here need to
3604 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3606 io_req_init_async(req
);
3607 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3613 static int io_tee_prep(struct io_kiocb
*req
,
3614 const struct io_uring_sqe
*sqe
)
3616 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3618 return __io_splice_prep(req
, sqe
);
3621 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
3623 struct io_splice
*sp
= &req
->splice
;
3624 struct file
*in
= sp
->file_in
;
3625 struct file
*out
= sp
->file_out
;
3626 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3632 ret
= do_tee(in
, out
, sp
->len
, flags
);
3634 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3635 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3638 req_set_fail_links(req
);
3639 io_req_complete(req
, ret
);
3643 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3645 struct io_splice
* sp
= &req
->splice
;
3647 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3648 sp
->off_out
= READ_ONCE(sqe
->off
);
3649 return __io_splice_prep(req
, sqe
);
3652 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
3654 struct io_splice
*sp
= &req
->splice
;
3655 struct file
*in
= sp
->file_in
;
3656 struct file
*out
= sp
->file_out
;
3657 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3658 loff_t
*poff_in
, *poff_out
;
3664 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3665 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3668 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3670 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3671 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3674 req_set_fail_links(req
);
3675 io_req_complete(req
, ret
);
3680 * IORING_OP_NOP just posts a completion event, nothing else.
3682 static int io_nop(struct io_kiocb
*req
, struct io_comp_state
*cs
)
3684 struct io_ring_ctx
*ctx
= req
->ctx
;
3686 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3689 __io_req_complete(req
, 0, 0, cs
);
3693 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3695 struct io_ring_ctx
*ctx
= req
->ctx
;
3700 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3702 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3705 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3706 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3709 req
->sync
.off
= READ_ONCE(sqe
->off
);
3710 req
->sync
.len
= READ_ONCE(sqe
->len
);
3714 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
3716 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3719 /* fsync always requires a blocking context */
3723 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3724 end
> 0 ? end
: LLONG_MAX
,
3725 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3727 req_set_fail_links(req
);
3728 io_req_complete(req
, ret
);
3732 static int io_fallocate_prep(struct io_kiocb
*req
,
3733 const struct io_uring_sqe
*sqe
)
3735 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3737 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3740 req
->sync
.off
= READ_ONCE(sqe
->off
);
3741 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3742 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3746 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
3750 /* fallocate always requiring blocking context */
3753 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3756 req_set_fail_links(req
);
3757 io_req_complete(req
, ret
);
3761 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3763 const char __user
*fname
;
3766 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3768 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3771 /* open.how should be already initialised */
3772 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3773 req
->open
.how
.flags
|= O_LARGEFILE
;
3775 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3776 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3777 req
->open
.filename
= getname(fname
);
3778 if (IS_ERR(req
->open
.filename
)) {
3779 ret
= PTR_ERR(req
->open
.filename
);
3780 req
->open
.filename
= NULL
;
3783 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3784 req
->flags
|= REQ_F_NEED_CLEANUP
;
3788 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3792 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3794 mode
= READ_ONCE(sqe
->len
);
3795 flags
= READ_ONCE(sqe
->open_flags
);
3796 req
->open
.how
= build_open_how(flags
, mode
);
3797 return __io_openat_prep(req
, sqe
);
3800 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3802 struct open_how __user
*how
;
3806 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3808 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3809 len
= READ_ONCE(sqe
->len
);
3810 if (len
< OPEN_HOW_SIZE_VER0
)
3813 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3818 return __io_openat_prep(req
, sqe
);
3821 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
3823 struct open_flags op
;
3830 ret
= build_open_flags(&req
->open
.how
, &op
);
3834 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3838 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3841 ret
= PTR_ERR(file
);
3843 fsnotify_open(file
);
3844 fd_install(ret
, file
);
3847 putname(req
->open
.filename
);
3848 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3850 req_set_fail_links(req
);
3851 io_req_complete(req
, ret
);
3855 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
3857 return io_openat2(req
, force_nonblock
);
3860 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3861 const struct io_uring_sqe
*sqe
)
3863 struct io_provide_buf
*p
= &req
->pbuf
;
3866 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3869 tmp
= READ_ONCE(sqe
->fd
);
3870 if (!tmp
|| tmp
> USHRT_MAX
)
3873 memset(p
, 0, sizeof(*p
));
3875 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3879 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3880 int bgid
, unsigned nbufs
)
3884 /* shouldn't happen */
3888 /* the head kbuf is the list itself */
3889 while (!list_empty(&buf
->list
)) {
3890 struct io_buffer
*nxt
;
3892 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3893 list_del(&nxt
->list
);
3900 idr_remove(&ctx
->io_buffer_idr
, bgid
);
3905 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3906 struct io_comp_state
*cs
)
3908 struct io_provide_buf
*p
= &req
->pbuf
;
3909 struct io_ring_ctx
*ctx
= req
->ctx
;
3910 struct io_buffer
*head
;
3913 io_ring_submit_lock(ctx
, !force_nonblock
);
3915 lockdep_assert_held(&ctx
->uring_lock
);
3918 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3920 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3922 io_ring_submit_lock(ctx
, !force_nonblock
);
3924 req_set_fail_links(req
);
3925 __io_req_complete(req
, ret
, 0, cs
);
3929 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3930 const struct io_uring_sqe
*sqe
)
3932 struct io_provide_buf
*p
= &req
->pbuf
;
3935 if (sqe
->ioprio
|| sqe
->rw_flags
)
3938 tmp
= READ_ONCE(sqe
->fd
);
3939 if (!tmp
|| tmp
> USHRT_MAX
)
3942 p
->addr
= READ_ONCE(sqe
->addr
);
3943 p
->len
= READ_ONCE(sqe
->len
);
3945 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
3948 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3949 tmp
= READ_ONCE(sqe
->off
);
3950 if (tmp
> USHRT_MAX
)
3956 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3958 struct io_buffer
*buf
;
3959 u64 addr
= pbuf
->addr
;
3960 int i
, bid
= pbuf
->bid
;
3962 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3963 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3968 buf
->len
= pbuf
->len
;
3973 INIT_LIST_HEAD(&buf
->list
);
3976 list_add_tail(&buf
->list
, &(*head
)->list
);
3980 return i
? i
: -ENOMEM
;
3983 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3984 struct io_comp_state
*cs
)
3986 struct io_provide_buf
*p
= &req
->pbuf
;
3987 struct io_ring_ctx
*ctx
= req
->ctx
;
3988 struct io_buffer
*head
, *list
;
3991 io_ring_submit_lock(ctx
, !force_nonblock
);
3993 lockdep_assert_held(&ctx
->uring_lock
);
3995 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3997 ret
= io_add_buffers(p
, &head
);
4002 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
4005 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4010 io_ring_submit_unlock(ctx
, !force_nonblock
);
4012 req_set_fail_links(req
);
4013 __io_req_complete(req
, ret
, 0, cs
);
4017 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4018 const struct io_uring_sqe
*sqe
)
4020 #if defined(CONFIG_EPOLL)
4021 if (sqe
->ioprio
|| sqe
->buf_index
)
4023 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4026 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4027 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4028 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4030 if (ep_op_has_event(req
->epoll
.op
)) {
4031 struct epoll_event __user
*ev
;
4033 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4034 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4044 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
,
4045 struct io_comp_state
*cs
)
4047 #if defined(CONFIG_EPOLL)
4048 struct io_epoll
*ie
= &req
->epoll
;
4051 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4052 if (force_nonblock
&& ret
== -EAGAIN
)
4056 req_set_fail_links(req
);
4057 __io_req_complete(req
, ret
, 0, cs
);
4064 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4066 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4067 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4069 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4072 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4073 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4074 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4081 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
4083 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4084 struct io_madvise
*ma
= &req
->madvise
;
4090 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4092 req_set_fail_links(req
);
4093 io_req_complete(req
, ret
);
4100 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4102 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4104 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4107 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4108 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4109 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4113 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
4115 struct io_fadvise
*fa
= &req
->fadvise
;
4118 if (force_nonblock
) {
4119 switch (fa
->advice
) {
4120 case POSIX_FADV_NORMAL
:
4121 case POSIX_FADV_RANDOM
:
4122 case POSIX_FADV_SEQUENTIAL
:
4129 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4131 req_set_fail_links(req
);
4132 io_req_complete(req
, ret
);
4136 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4138 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4140 if (sqe
->ioprio
|| sqe
->buf_index
)
4142 if (req
->flags
& REQ_F_FIXED_FILE
)
4145 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4146 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4147 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4148 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4149 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4154 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
4156 struct io_statx
*ctx
= &req
->statx
;
4159 if (force_nonblock
) {
4160 /* only need file table for an actual valid fd */
4161 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
4162 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4166 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4170 req_set_fail_links(req
);
4171 io_req_complete(req
, ret
);
4175 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4178 * If we queue this for async, it must not be cancellable. That would
4179 * leave the 'file' in an undeterminate state, and here need to modify
4180 * io_wq_work.flags, so initialize io_wq_work firstly.
4182 io_req_init_async(req
);
4183 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
4185 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4187 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4188 sqe
->rw_flags
|| sqe
->buf_index
)
4190 if (req
->flags
& REQ_F_FIXED_FILE
)
4193 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4194 if ((req
->file
&& req
->file
->f_op
== &io_uring_fops
))
4197 req
->close
.put_file
= NULL
;
4201 static int io_close(struct io_kiocb
*req
, bool force_nonblock
,
4202 struct io_comp_state
*cs
)
4204 struct io_close
*close
= &req
->close
;
4207 /* might be already done during nonblock submission */
4208 if (!close
->put_file
) {
4209 ret
= __close_fd_get_file(close
->fd
, &close
->put_file
);
4211 return (ret
== -ENOENT
) ? -EBADF
: ret
;
4214 /* if the file has a flush method, be safe and punt to async */
4215 if (close
->put_file
->f_op
->flush
&& force_nonblock
) {
4216 /* was never set, but play safe */
4217 req
->flags
&= ~REQ_F_NOWAIT
;
4218 /* avoid grabbing files - we don't need the files */
4219 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4223 /* No ->flush() or already async, safely close from here */
4224 ret
= filp_close(close
->put_file
, req
->work
.identity
->files
);
4226 req_set_fail_links(req
);
4227 fput(close
->put_file
);
4228 close
->put_file
= NULL
;
4229 __io_req_complete(req
, ret
, 0, cs
);
4233 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4235 struct io_ring_ctx
*ctx
= req
->ctx
;
4240 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4242 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4245 req
->sync
.off
= READ_ONCE(sqe
->off
);
4246 req
->sync
.len
= READ_ONCE(sqe
->len
);
4247 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4251 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
4255 /* sync_file_range always requires a blocking context */
4259 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4262 req_set_fail_links(req
);
4263 io_req_complete(req
, ret
);
4267 #if defined(CONFIG_NET)
4268 static int io_setup_async_msg(struct io_kiocb
*req
,
4269 struct io_async_msghdr
*kmsg
)
4271 struct io_async_msghdr
*async_msg
= req
->async_data
;
4275 if (io_alloc_async_data(req
)) {
4276 if (kmsg
->iov
!= kmsg
->fast_iov
)
4280 async_msg
= req
->async_data
;
4281 req
->flags
|= REQ_F_NEED_CLEANUP
;
4282 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4286 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4287 struct io_async_msghdr
*iomsg
)
4289 iomsg
->iov
= iomsg
->fast_iov
;
4290 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4291 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4292 req
->sr_msg
.msg_flags
, &iomsg
->iov
);
4295 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4297 struct io_async_msghdr
*async_msg
= req
->async_data
;
4298 struct io_sr_msg
*sr
= &req
->sr_msg
;
4301 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4304 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4305 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4306 sr
->len
= READ_ONCE(sqe
->len
);
4308 #ifdef CONFIG_COMPAT
4309 if (req
->ctx
->compat
)
4310 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4313 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4315 ret
= io_sendmsg_copy_hdr(req
, async_msg
);
4317 req
->flags
|= REQ_F_NEED_CLEANUP
;
4321 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4322 struct io_comp_state
*cs
)
4324 struct io_async_msghdr iomsg
, *kmsg
;
4325 struct socket
*sock
;
4329 sock
= sock_from_file(req
->file
, &ret
);
4330 if (unlikely(!sock
))
4333 if (req
->async_data
) {
4334 kmsg
= req
->async_data
;
4335 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4336 /* if iov is set, it's allocated already */
4338 kmsg
->iov
= kmsg
->fast_iov
;
4339 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4341 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4347 flags
= req
->sr_msg
.msg_flags
;
4348 if (flags
& MSG_DONTWAIT
)
4349 req
->flags
|= REQ_F_NOWAIT
;
4350 else if (force_nonblock
)
4351 flags
|= MSG_DONTWAIT
;
4353 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4354 if (force_nonblock
&& ret
== -EAGAIN
)
4355 return io_setup_async_msg(req
, kmsg
);
4356 if (ret
== -ERESTARTSYS
)
4359 if (kmsg
->iov
!= kmsg
->fast_iov
)
4361 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4363 req_set_fail_links(req
);
4364 __io_req_complete(req
, ret
, 0, cs
);
4368 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4369 struct io_comp_state
*cs
)
4371 struct io_sr_msg
*sr
= &req
->sr_msg
;
4374 struct socket
*sock
;
4378 sock
= sock_from_file(req
->file
, &ret
);
4379 if (unlikely(!sock
))
4382 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4386 msg
.msg_name
= NULL
;
4387 msg
.msg_control
= NULL
;
4388 msg
.msg_controllen
= 0;
4389 msg
.msg_namelen
= 0;
4391 flags
= req
->sr_msg
.msg_flags
;
4392 if (flags
& MSG_DONTWAIT
)
4393 req
->flags
|= REQ_F_NOWAIT
;
4394 else if (force_nonblock
)
4395 flags
|= MSG_DONTWAIT
;
4397 msg
.msg_flags
= flags
;
4398 ret
= sock_sendmsg(sock
, &msg
);
4399 if (force_nonblock
&& ret
== -EAGAIN
)
4401 if (ret
== -ERESTARTSYS
)
4405 req_set_fail_links(req
);
4406 __io_req_complete(req
, ret
, 0, cs
);
4410 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4411 struct io_async_msghdr
*iomsg
)
4413 struct io_sr_msg
*sr
= &req
->sr_msg
;
4414 struct iovec __user
*uiov
;
4418 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4419 &iomsg
->uaddr
, &uiov
, &iov_len
);
4423 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4426 if (copy_from_user(iomsg
->iov
, uiov
, sizeof(*uiov
)))
4428 sr
->len
= iomsg
->iov
[0].iov_len
;
4429 iov_iter_init(&iomsg
->msg
.msg_iter
, READ
, iomsg
->iov
, 1,
4433 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4434 &iomsg
->iov
, &iomsg
->msg
.msg_iter
,
4443 #ifdef CONFIG_COMPAT
4444 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4445 struct io_async_msghdr
*iomsg
)
4447 struct compat_msghdr __user
*msg_compat
;
4448 struct io_sr_msg
*sr
= &req
->sr_msg
;
4449 struct compat_iovec __user
*uiov
;
4454 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4455 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4460 uiov
= compat_ptr(ptr
);
4461 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4462 compat_ssize_t clen
;
4466 if (!access_ok(uiov
, sizeof(*uiov
)))
4468 if (__get_user(clen
, &uiov
->iov_len
))
4472 sr
->len
= iomsg
->iov
[0].iov_len
;
4475 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4476 UIO_FASTIOV
, &iomsg
->iov
,
4477 &iomsg
->msg
.msg_iter
, true);
4486 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4487 struct io_async_msghdr
*iomsg
)
4489 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4490 iomsg
->iov
= iomsg
->fast_iov
;
4492 #ifdef CONFIG_COMPAT
4493 if (req
->ctx
->compat
)
4494 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4497 return __io_recvmsg_copy_hdr(req
, iomsg
);
4500 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4503 struct io_sr_msg
*sr
= &req
->sr_msg
;
4504 struct io_buffer
*kbuf
;
4506 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4511 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4515 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4517 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4520 static int io_recvmsg_prep(struct io_kiocb
*req
,
4521 const struct io_uring_sqe
*sqe
)
4523 struct io_async_msghdr
*async_msg
= req
->async_data
;
4524 struct io_sr_msg
*sr
= &req
->sr_msg
;
4527 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4530 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4531 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4532 sr
->len
= READ_ONCE(sqe
->len
);
4533 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4535 #ifdef CONFIG_COMPAT
4536 if (req
->ctx
->compat
)
4537 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4540 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4542 ret
= io_recvmsg_copy_hdr(req
, async_msg
);
4544 req
->flags
|= REQ_F_NEED_CLEANUP
;
4548 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4549 struct io_comp_state
*cs
)
4551 struct io_async_msghdr iomsg
, *kmsg
;
4552 struct socket
*sock
;
4553 struct io_buffer
*kbuf
;
4555 int ret
, cflags
= 0;
4557 sock
= sock_from_file(req
->file
, &ret
);
4558 if (unlikely(!sock
))
4561 if (req
->async_data
) {
4562 kmsg
= req
->async_data
;
4563 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4564 /* if iov is set, it's allocated already */
4566 kmsg
->iov
= kmsg
->fast_iov
;
4567 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4569 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4575 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4576 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4578 return PTR_ERR(kbuf
);
4579 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4580 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
4581 1, req
->sr_msg
.len
);
4584 flags
= req
->sr_msg
.msg_flags
;
4585 if (flags
& MSG_DONTWAIT
)
4586 req
->flags
|= REQ_F_NOWAIT
;
4587 else if (force_nonblock
)
4588 flags
|= MSG_DONTWAIT
;
4590 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4591 kmsg
->uaddr
, flags
);
4592 if (force_nonblock
&& ret
== -EAGAIN
)
4593 return io_setup_async_msg(req
, kmsg
);
4594 if (ret
== -ERESTARTSYS
)
4597 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4598 cflags
= io_put_recv_kbuf(req
);
4599 if (kmsg
->iov
!= kmsg
->fast_iov
)
4601 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4603 req_set_fail_links(req
);
4604 __io_req_complete(req
, ret
, cflags
, cs
);
4608 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4609 struct io_comp_state
*cs
)
4611 struct io_buffer
*kbuf
;
4612 struct io_sr_msg
*sr
= &req
->sr_msg
;
4614 void __user
*buf
= sr
->buf
;
4615 struct socket
*sock
;
4618 int ret
, cflags
= 0;
4620 sock
= sock_from_file(req
->file
, &ret
);
4621 if (unlikely(!sock
))
4624 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4625 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4627 return PTR_ERR(kbuf
);
4628 buf
= u64_to_user_ptr(kbuf
->addr
);
4631 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4635 msg
.msg_name
= NULL
;
4636 msg
.msg_control
= NULL
;
4637 msg
.msg_controllen
= 0;
4638 msg
.msg_namelen
= 0;
4639 msg
.msg_iocb
= NULL
;
4642 flags
= req
->sr_msg
.msg_flags
;
4643 if (flags
& MSG_DONTWAIT
)
4644 req
->flags
|= REQ_F_NOWAIT
;
4645 else if (force_nonblock
)
4646 flags
|= MSG_DONTWAIT
;
4648 ret
= sock_recvmsg(sock
, &msg
, flags
);
4649 if (force_nonblock
&& ret
== -EAGAIN
)
4651 if (ret
== -ERESTARTSYS
)
4654 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4655 cflags
= io_put_recv_kbuf(req
);
4657 req_set_fail_links(req
);
4658 __io_req_complete(req
, ret
, cflags
, cs
);
4662 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4664 struct io_accept
*accept
= &req
->accept
;
4666 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4668 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4671 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4672 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4673 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4674 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4678 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4679 struct io_comp_state
*cs
)
4681 struct io_accept
*accept
= &req
->accept
;
4682 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4685 if (req
->file
->f_flags
& O_NONBLOCK
)
4686 req
->flags
|= REQ_F_NOWAIT
;
4688 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4689 accept
->addr_len
, accept
->flags
,
4691 if (ret
== -EAGAIN
&& force_nonblock
)
4694 if (ret
== -ERESTARTSYS
)
4696 req_set_fail_links(req
);
4698 __io_req_complete(req
, ret
, 0, cs
);
4702 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4704 struct io_connect
*conn
= &req
->connect
;
4705 struct io_async_connect
*io
= req
->async_data
;
4707 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4709 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4712 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4713 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4718 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4722 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4723 struct io_comp_state
*cs
)
4725 struct io_async_connect __io
, *io
;
4726 unsigned file_flags
;
4729 if (req
->async_data
) {
4730 io
= req
->async_data
;
4732 ret
= move_addr_to_kernel(req
->connect
.addr
,
4733 req
->connect
.addr_len
,
4740 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4742 ret
= __sys_connect_file(req
->file
, &io
->address
,
4743 req
->connect
.addr_len
, file_flags
);
4744 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4745 if (req
->async_data
)
4747 if (io_alloc_async_data(req
)) {
4751 io
= req
->async_data
;
4752 memcpy(req
->async_data
, &__io
, sizeof(__io
));
4755 if (ret
== -ERESTARTSYS
)
4759 req_set_fail_links(req
);
4760 __io_req_complete(req
, ret
, 0, cs
);
4763 #else /* !CONFIG_NET */
4764 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4769 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4770 struct io_comp_state
*cs
)
4775 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4776 struct io_comp_state
*cs
)
4781 static int io_recvmsg_prep(struct io_kiocb
*req
,
4782 const struct io_uring_sqe
*sqe
)
4787 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4788 struct io_comp_state
*cs
)
4793 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4794 struct io_comp_state
*cs
)
4799 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4804 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4805 struct io_comp_state
*cs
)
4810 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4815 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4816 struct io_comp_state
*cs
)
4820 #endif /* CONFIG_NET */
4822 struct io_poll_table
{
4823 struct poll_table_struct pt
;
4824 struct io_kiocb
*req
;
4828 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4829 __poll_t mask
, task_work_func_t func
)
4834 /* for instances that support it check for an event match first: */
4835 if (mask
&& !(mask
& poll
->events
))
4838 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4840 list_del_init(&poll
->wait
.entry
);
4843 init_task_work(&req
->task_work
, func
);
4844 percpu_ref_get(&req
->ctx
->refs
);
4847 * If we using the signalfd wait_queue_head for this wakeup, then
4848 * it's not safe to use TWA_SIGNAL as we could be recursing on the
4849 * tsk->sighand->siglock on doing the wakeup. Should not be needed
4850 * either, as the normal wakeup will suffice.
4852 twa_signal_ok
= (poll
->head
!= &req
->task
->sighand
->signalfd_wqh
);
4855 * If this fails, then the task is exiting. When a task exits, the
4856 * work gets canceled, so just cancel this request as well instead
4857 * of executing it. We can't safely execute it anyway, as we may not
4858 * have the needed state needed for it anyway.
4860 ret
= io_req_task_work_add(req
, twa_signal_ok
);
4861 if (unlikely(ret
)) {
4862 struct task_struct
*tsk
;
4864 WRITE_ONCE(poll
->canceled
, true);
4865 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
4866 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
4867 wake_up_process(tsk
);
4872 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4873 __acquires(&req
->ctx
->completion_lock
)
4875 struct io_ring_ctx
*ctx
= req
->ctx
;
4877 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4878 struct poll_table_struct pt
= { ._key
= poll
->events
};
4880 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4883 spin_lock_irq(&ctx
->completion_lock
);
4884 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4885 add_wait_queue(poll
->head
, &poll
->wait
);
4892 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
4894 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
4895 if (req
->opcode
== IORING_OP_POLL_ADD
)
4896 return req
->async_data
;
4897 return req
->apoll
->double_poll
;
4900 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
4902 if (req
->opcode
== IORING_OP_POLL_ADD
)
4904 return &req
->apoll
->poll
;
4907 static void io_poll_remove_double(struct io_kiocb
*req
)
4909 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
4911 lockdep_assert_held(&req
->ctx
->completion_lock
);
4913 if (poll
&& poll
->head
) {
4914 struct wait_queue_head
*head
= poll
->head
;
4916 spin_lock(&head
->lock
);
4917 list_del_init(&poll
->wait
.entry
);
4918 if (poll
->wait
.private)
4919 refcount_dec(&req
->refs
);
4921 spin_unlock(&head
->lock
);
4925 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4927 struct io_ring_ctx
*ctx
= req
->ctx
;
4929 io_poll_remove_double(req
);
4930 req
->poll
.done
= true;
4931 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
4932 io_commit_cqring(ctx
);
4935 static void io_poll_task_func(struct callback_head
*cb
)
4937 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4938 struct io_ring_ctx
*ctx
= req
->ctx
;
4939 struct io_kiocb
*nxt
;
4941 if (io_poll_rewait(req
, &req
->poll
)) {
4942 spin_unlock_irq(&ctx
->completion_lock
);
4944 hash_del(&req
->hash_node
);
4945 io_poll_complete(req
, req
->result
, 0);
4946 spin_unlock_irq(&ctx
->completion_lock
);
4948 nxt
= io_put_req_find_next(req
);
4949 io_cqring_ev_posted(ctx
);
4951 __io_req_task_submit(nxt
);
4954 percpu_ref_put(&ctx
->refs
);
4957 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4958 int sync
, void *key
)
4960 struct io_kiocb
*req
= wait
->private;
4961 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
4962 __poll_t mask
= key_to_poll(key
);
4964 /* for instances that support it check for an event match first: */
4965 if (mask
&& !(mask
& poll
->events
))
4968 list_del_init(&wait
->entry
);
4970 if (poll
&& poll
->head
) {
4973 spin_lock(&poll
->head
->lock
);
4974 done
= list_empty(&poll
->wait
.entry
);
4976 list_del_init(&poll
->wait
.entry
);
4977 /* make sure double remove sees this as being gone */
4978 wait
->private = NULL
;
4979 spin_unlock(&poll
->head
->lock
);
4981 __io_async_wake(req
, poll
, mask
, io_poll_task_func
);
4983 refcount_dec(&req
->refs
);
4987 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
4988 wait_queue_func_t wake_func
)
4992 poll
->canceled
= false;
4993 poll
->events
= events
;
4994 INIT_LIST_HEAD(&poll
->wait
.entry
);
4995 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
4998 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
4999 struct wait_queue_head
*head
,
5000 struct io_poll_iocb
**poll_ptr
)
5002 struct io_kiocb
*req
= pt
->req
;
5005 * If poll->head is already set, it's because the file being polled
5006 * uses multiple waitqueues for poll handling (eg one for read, one
5007 * for write). Setup a separate io_poll_iocb if this happens.
5009 if (unlikely(poll
->head
)) {
5010 struct io_poll_iocb
*poll_one
= poll
;
5012 /* already have a 2nd entry, fail a third attempt */
5014 pt
->error
= -EINVAL
;
5017 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5019 pt
->error
= -ENOMEM
;
5022 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5023 refcount_inc(&req
->refs
);
5024 poll
->wait
.private = req
;
5031 if (poll
->events
& EPOLLEXCLUSIVE
)
5032 add_wait_queue_exclusive(head
, &poll
->wait
);
5034 add_wait_queue(head
, &poll
->wait
);
5037 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5038 struct poll_table_struct
*p
)
5040 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5041 struct async_poll
*apoll
= pt
->req
->apoll
;
5043 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5046 static void io_async_task_func(struct callback_head
*cb
)
5048 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5049 struct async_poll
*apoll
= req
->apoll
;
5050 struct io_ring_ctx
*ctx
= req
->ctx
;
5052 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5054 if (io_poll_rewait(req
, &apoll
->poll
)) {
5055 spin_unlock_irq(&ctx
->completion_lock
);
5056 percpu_ref_put(&ctx
->refs
);
5060 /* If req is still hashed, it cannot have been canceled. Don't check. */
5061 if (hash_hashed(&req
->hash_node
))
5062 hash_del(&req
->hash_node
);
5064 io_poll_remove_double(req
);
5065 spin_unlock_irq(&ctx
->completion_lock
);
5067 if (!READ_ONCE(apoll
->poll
.canceled
))
5068 __io_req_task_submit(req
);
5070 __io_req_task_cancel(req
, -ECANCELED
);
5072 percpu_ref_put(&ctx
->refs
);
5073 kfree(apoll
->double_poll
);
5077 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5080 struct io_kiocb
*req
= wait
->private;
5081 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5083 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5086 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5089 static void io_poll_req_insert(struct io_kiocb
*req
)
5091 struct io_ring_ctx
*ctx
= req
->ctx
;
5092 struct hlist_head
*list
;
5094 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5095 hlist_add_head(&req
->hash_node
, list
);
5098 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5099 struct io_poll_iocb
*poll
,
5100 struct io_poll_table
*ipt
, __poll_t mask
,
5101 wait_queue_func_t wake_func
)
5102 __acquires(&ctx
->completion_lock
)
5104 struct io_ring_ctx
*ctx
= req
->ctx
;
5105 bool cancel
= false;
5107 INIT_HLIST_NODE(&req
->hash_node
);
5108 io_init_poll_iocb(poll
, mask
, wake_func
);
5109 poll
->file
= req
->file
;
5110 poll
->wait
.private = req
;
5112 ipt
->pt
._key
= mask
;
5114 ipt
->error
= -EINVAL
;
5116 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5118 spin_lock_irq(&ctx
->completion_lock
);
5119 if (likely(poll
->head
)) {
5120 spin_lock(&poll
->head
->lock
);
5121 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5127 if (mask
|| ipt
->error
)
5128 list_del_init(&poll
->wait
.entry
);
5130 WRITE_ONCE(poll
->canceled
, true);
5131 else if (!poll
->done
) /* actually waiting for an event */
5132 io_poll_req_insert(req
);
5133 spin_unlock(&poll
->head
->lock
);
5139 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5141 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5142 struct io_ring_ctx
*ctx
= req
->ctx
;
5143 struct async_poll
*apoll
;
5144 struct io_poll_table ipt
;
5148 if (!req
->file
|| !file_can_poll(req
->file
))
5150 if (req
->flags
& REQ_F_POLLED
)
5154 else if (def
->pollout
)
5158 /* if we can't nonblock try, then no point in arming a poll handler */
5159 if (!io_file_supports_async(req
->file
, rw
))
5162 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5163 if (unlikely(!apoll
))
5165 apoll
->double_poll
= NULL
;
5167 req
->flags
|= REQ_F_POLLED
;
5172 mask
|= POLLIN
| POLLRDNORM
;
5174 mask
|= POLLOUT
| POLLWRNORM
;
5176 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5177 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5178 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5181 mask
|= POLLERR
| POLLPRI
;
5183 ipt
.pt
._qproc
= io_async_queue_proc
;
5185 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5187 if (ret
|| ipt
.error
) {
5188 io_poll_remove_double(req
);
5189 spin_unlock_irq(&ctx
->completion_lock
);
5190 kfree(apoll
->double_poll
);
5194 spin_unlock_irq(&ctx
->completion_lock
);
5195 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5196 apoll
->poll
.events
);
5200 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5201 struct io_poll_iocb
*poll
)
5203 bool do_complete
= false;
5205 spin_lock(&poll
->head
->lock
);
5206 WRITE_ONCE(poll
->canceled
, true);
5207 if (!list_empty(&poll
->wait
.entry
)) {
5208 list_del_init(&poll
->wait
.entry
);
5211 spin_unlock(&poll
->head
->lock
);
5212 hash_del(&req
->hash_node
);
5216 static bool io_poll_remove_one(struct io_kiocb
*req
)
5220 io_poll_remove_double(req
);
5222 if (req
->opcode
== IORING_OP_POLL_ADD
) {
5223 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
5225 struct async_poll
*apoll
= req
->apoll
;
5227 /* non-poll requests have submit ref still */
5228 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
5231 kfree(apoll
->double_poll
);
5237 io_cqring_fill_event(req
, -ECANCELED
);
5238 io_commit_cqring(req
->ctx
);
5239 req_set_fail_links(req
);
5240 io_put_req_deferred(req
, 1);
5247 * Returns true if we found and killed one or more poll requests
5249 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
)
5251 struct hlist_node
*tmp
;
5252 struct io_kiocb
*req
;
5255 spin_lock_irq(&ctx
->completion_lock
);
5256 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5257 struct hlist_head
*list
;
5259 list
= &ctx
->cancel_hash
[i
];
5260 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5261 if (io_task_match(req
, tsk
))
5262 posted
+= io_poll_remove_one(req
);
5265 spin_unlock_irq(&ctx
->completion_lock
);
5268 io_cqring_ev_posted(ctx
);
5273 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5275 struct hlist_head
*list
;
5276 struct io_kiocb
*req
;
5278 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5279 hlist_for_each_entry(req
, list
, hash_node
) {
5280 if (sqe_addr
!= req
->user_data
)
5282 if (io_poll_remove_one(req
))
5290 static int io_poll_remove_prep(struct io_kiocb
*req
,
5291 const struct io_uring_sqe
*sqe
)
5293 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5295 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5299 req
->poll
.addr
= READ_ONCE(sqe
->addr
);
5304 * Find a running poll command that matches one specified in sqe->addr,
5305 * and remove it if found.
5307 static int io_poll_remove(struct io_kiocb
*req
)
5309 struct io_ring_ctx
*ctx
= req
->ctx
;
5313 addr
= req
->poll
.addr
;
5314 spin_lock_irq(&ctx
->completion_lock
);
5315 ret
= io_poll_cancel(ctx
, addr
);
5316 spin_unlock_irq(&ctx
->completion_lock
);
5319 req_set_fail_links(req
);
5320 io_req_complete(req
, ret
);
5324 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5327 struct io_kiocb
*req
= wait
->private;
5328 struct io_poll_iocb
*poll
= &req
->poll
;
5330 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5333 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5334 struct poll_table_struct
*p
)
5336 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5338 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5341 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5343 struct io_poll_iocb
*poll
= &req
->poll
;
5346 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5348 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
5351 events
= READ_ONCE(sqe
->poll32_events
);
5353 events
= swahw32(events
);
5355 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
5356 (events
& EPOLLEXCLUSIVE
);
5360 static int io_poll_add(struct io_kiocb
*req
)
5362 struct io_poll_iocb
*poll
= &req
->poll
;
5363 struct io_ring_ctx
*ctx
= req
->ctx
;
5364 struct io_poll_table ipt
;
5367 ipt
.pt
._qproc
= io_poll_queue_proc
;
5369 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5372 if (mask
) { /* no async, we'd stolen it */
5374 io_poll_complete(req
, mask
, 0);
5376 spin_unlock_irq(&ctx
->completion_lock
);
5379 io_cqring_ev_posted(ctx
);
5385 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5387 struct io_timeout_data
*data
= container_of(timer
,
5388 struct io_timeout_data
, timer
);
5389 struct io_kiocb
*req
= data
->req
;
5390 struct io_ring_ctx
*ctx
= req
->ctx
;
5391 unsigned long flags
;
5393 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5394 list_del_init(&req
->timeout
.list
);
5395 atomic_set(&req
->ctx
->cq_timeouts
,
5396 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5398 io_cqring_fill_event(req
, -ETIME
);
5399 io_commit_cqring(ctx
);
5400 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5402 io_cqring_ev_posted(ctx
);
5403 req_set_fail_links(req
);
5405 return HRTIMER_NORESTART
;
5408 static int __io_timeout_cancel(struct io_kiocb
*req
)
5410 struct io_timeout_data
*io
= req
->async_data
;
5413 ret
= hrtimer_try_to_cancel(&io
->timer
);
5416 list_del_init(&req
->timeout
.list
);
5418 req_set_fail_links(req
);
5419 io_cqring_fill_event(req
, -ECANCELED
);
5420 io_put_req_deferred(req
, 1);
5424 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5426 struct io_kiocb
*req
;
5429 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5430 if (user_data
== req
->user_data
) {
5439 return __io_timeout_cancel(req
);
5442 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5443 const struct io_uring_sqe
*sqe
)
5445 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5447 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5449 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
|| sqe
->timeout_flags
)
5452 req
->timeout_rem
.addr
= READ_ONCE(sqe
->addr
);
5457 * Remove or update an existing timeout command
5459 static int io_timeout_remove(struct io_kiocb
*req
)
5461 struct io_ring_ctx
*ctx
= req
->ctx
;
5464 spin_lock_irq(&ctx
->completion_lock
);
5465 ret
= io_timeout_cancel(ctx
, req
->timeout_rem
.addr
);
5467 io_cqring_fill_event(req
, ret
);
5468 io_commit_cqring(ctx
);
5469 spin_unlock_irq(&ctx
->completion_lock
);
5470 io_cqring_ev_posted(ctx
);
5472 req_set_fail_links(req
);
5477 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5478 bool is_timeout_link
)
5480 struct io_timeout_data
*data
;
5482 u32 off
= READ_ONCE(sqe
->off
);
5484 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5486 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5488 if (off
&& is_timeout_link
)
5490 flags
= READ_ONCE(sqe
->timeout_flags
);
5491 if (flags
& ~IORING_TIMEOUT_ABS
)
5494 req
->timeout
.off
= off
;
5496 if (!req
->async_data
&& io_alloc_async_data(req
))
5499 data
= req
->async_data
;
5502 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5505 if (flags
& IORING_TIMEOUT_ABS
)
5506 data
->mode
= HRTIMER_MODE_ABS
;
5508 data
->mode
= HRTIMER_MODE_REL
;
5510 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5514 static int io_timeout(struct io_kiocb
*req
)
5516 struct io_ring_ctx
*ctx
= req
->ctx
;
5517 struct io_timeout_data
*data
= req
->async_data
;
5518 struct list_head
*entry
;
5519 u32 tail
, off
= req
->timeout
.off
;
5521 spin_lock_irq(&ctx
->completion_lock
);
5524 * sqe->off holds how many events that need to occur for this
5525 * timeout event to be satisfied. If it isn't set, then this is
5526 * a pure timeout request, sequence isn't used.
5528 if (io_is_timeout_noseq(req
)) {
5529 entry
= ctx
->timeout_list
.prev
;
5533 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5534 req
->timeout
.target_seq
= tail
+ off
;
5537 * Insertion sort, ensuring the first entry in the list is always
5538 * the one we need first.
5540 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5541 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5544 if (io_is_timeout_noseq(nxt
))
5546 /* nxt.seq is behind @tail, otherwise would've been completed */
5547 if (off
>= nxt
->timeout
.target_seq
- tail
)
5551 list_add(&req
->timeout
.list
, entry
);
5552 data
->timer
.function
= io_timeout_fn
;
5553 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5554 spin_unlock_irq(&ctx
->completion_lock
);
5558 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5560 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5562 return req
->user_data
== (unsigned long) data
;
5565 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5567 enum io_wq_cancel cancel_ret
;
5570 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5571 switch (cancel_ret
) {
5572 case IO_WQ_CANCEL_OK
:
5575 case IO_WQ_CANCEL_RUNNING
:
5578 case IO_WQ_CANCEL_NOTFOUND
:
5586 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5587 struct io_kiocb
*req
, __u64 sqe_addr
,
5590 unsigned long flags
;
5593 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5594 if (ret
!= -ENOENT
) {
5595 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5599 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5600 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5603 ret
= io_poll_cancel(ctx
, sqe_addr
);
5607 io_cqring_fill_event(req
, ret
);
5608 io_commit_cqring(ctx
);
5609 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5610 io_cqring_ev_posted(ctx
);
5613 req_set_fail_links(req
);
5617 static int io_async_cancel_prep(struct io_kiocb
*req
,
5618 const struct io_uring_sqe
*sqe
)
5620 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5622 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5624 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5627 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5631 static int io_async_cancel(struct io_kiocb
*req
)
5633 struct io_ring_ctx
*ctx
= req
->ctx
;
5635 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
5639 static int io_files_update_prep(struct io_kiocb
*req
,
5640 const struct io_uring_sqe
*sqe
)
5642 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
5644 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5646 if (sqe
->ioprio
|| sqe
->rw_flags
)
5649 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
5650 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
5651 if (!req
->files_update
.nr_args
)
5653 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
5657 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
,
5658 struct io_comp_state
*cs
)
5660 struct io_ring_ctx
*ctx
= req
->ctx
;
5661 struct io_uring_files_update up
;
5667 up
.offset
= req
->files_update
.offset
;
5668 up
.fds
= req
->files_update
.arg
;
5670 mutex_lock(&ctx
->uring_lock
);
5671 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
5672 mutex_unlock(&ctx
->uring_lock
);
5675 req_set_fail_links(req
);
5676 __io_req_complete(req
, ret
, 0, cs
);
5680 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5682 switch (req
->opcode
) {
5685 case IORING_OP_READV
:
5686 case IORING_OP_READ_FIXED
:
5687 case IORING_OP_READ
:
5688 return io_read_prep(req
, sqe
);
5689 case IORING_OP_WRITEV
:
5690 case IORING_OP_WRITE_FIXED
:
5691 case IORING_OP_WRITE
:
5692 return io_write_prep(req
, sqe
);
5693 case IORING_OP_POLL_ADD
:
5694 return io_poll_add_prep(req
, sqe
);
5695 case IORING_OP_POLL_REMOVE
:
5696 return io_poll_remove_prep(req
, sqe
);
5697 case IORING_OP_FSYNC
:
5698 return io_prep_fsync(req
, sqe
);
5699 case IORING_OP_SYNC_FILE_RANGE
:
5700 return io_prep_sfr(req
, sqe
);
5701 case IORING_OP_SENDMSG
:
5702 case IORING_OP_SEND
:
5703 return io_sendmsg_prep(req
, sqe
);
5704 case IORING_OP_RECVMSG
:
5705 case IORING_OP_RECV
:
5706 return io_recvmsg_prep(req
, sqe
);
5707 case IORING_OP_CONNECT
:
5708 return io_connect_prep(req
, sqe
);
5709 case IORING_OP_TIMEOUT
:
5710 return io_timeout_prep(req
, sqe
, false);
5711 case IORING_OP_TIMEOUT_REMOVE
:
5712 return io_timeout_remove_prep(req
, sqe
);
5713 case IORING_OP_ASYNC_CANCEL
:
5714 return io_async_cancel_prep(req
, sqe
);
5715 case IORING_OP_LINK_TIMEOUT
:
5716 return io_timeout_prep(req
, sqe
, true);
5717 case IORING_OP_ACCEPT
:
5718 return io_accept_prep(req
, sqe
);
5719 case IORING_OP_FALLOCATE
:
5720 return io_fallocate_prep(req
, sqe
);
5721 case IORING_OP_OPENAT
:
5722 return io_openat_prep(req
, sqe
);
5723 case IORING_OP_CLOSE
:
5724 return io_close_prep(req
, sqe
);
5725 case IORING_OP_FILES_UPDATE
:
5726 return io_files_update_prep(req
, sqe
);
5727 case IORING_OP_STATX
:
5728 return io_statx_prep(req
, sqe
);
5729 case IORING_OP_FADVISE
:
5730 return io_fadvise_prep(req
, sqe
);
5731 case IORING_OP_MADVISE
:
5732 return io_madvise_prep(req
, sqe
);
5733 case IORING_OP_OPENAT2
:
5734 return io_openat2_prep(req
, sqe
);
5735 case IORING_OP_EPOLL_CTL
:
5736 return io_epoll_ctl_prep(req
, sqe
);
5737 case IORING_OP_SPLICE
:
5738 return io_splice_prep(req
, sqe
);
5739 case IORING_OP_PROVIDE_BUFFERS
:
5740 return io_provide_buffers_prep(req
, sqe
);
5741 case IORING_OP_REMOVE_BUFFERS
:
5742 return io_remove_buffers_prep(req
, sqe
);
5744 return io_tee_prep(req
, sqe
);
5747 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5752 static int io_req_defer_prep(struct io_kiocb
*req
,
5753 const struct io_uring_sqe
*sqe
)
5757 if (io_alloc_async_data(req
))
5759 return io_req_prep(req
, sqe
);
5762 static u32
io_get_sequence(struct io_kiocb
*req
)
5764 struct io_kiocb
*pos
;
5765 struct io_ring_ctx
*ctx
= req
->ctx
;
5766 u32 total_submitted
, nr_reqs
= 1;
5768 if (req
->flags
& REQ_F_LINK_HEAD
)
5769 list_for_each_entry(pos
, &req
->link_list
, link_list
)
5772 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5773 return total_submitted
- nr_reqs
;
5776 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5778 struct io_ring_ctx
*ctx
= req
->ctx
;
5779 struct io_defer_entry
*de
;
5783 /* Still need defer if there is pending req in defer list. */
5784 if (likely(list_empty_careful(&ctx
->defer_list
) &&
5785 !(req
->flags
& REQ_F_IO_DRAIN
)))
5788 seq
= io_get_sequence(req
);
5789 /* Still a chance to pass the sequence check */
5790 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
5793 if (!req
->async_data
) {
5794 ret
= io_req_defer_prep(req
, sqe
);
5798 io_prep_async_link(req
);
5799 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
5803 spin_lock_irq(&ctx
->completion_lock
);
5804 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
5805 spin_unlock_irq(&ctx
->completion_lock
);
5807 io_queue_async_work(req
);
5808 return -EIOCBQUEUED
;
5811 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5814 list_add_tail(&de
->list
, &ctx
->defer_list
);
5815 spin_unlock_irq(&ctx
->completion_lock
);
5816 return -EIOCBQUEUED
;
5819 static void io_req_drop_files(struct io_kiocb
*req
)
5821 struct io_ring_ctx
*ctx
= req
->ctx
;
5822 unsigned long flags
;
5824 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
5825 list_del(&req
->inflight_entry
);
5826 if (waitqueue_active(&ctx
->inflight_wait
))
5827 wake_up(&ctx
->inflight_wait
);
5828 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
5829 req
->flags
&= ~REQ_F_INFLIGHT
;
5830 put_files_struct(req
->work
.identity
->files
);
5831 put_nsproxy(req
->work
.identity
->nsproxy
);
5832 req
->work
.flags
&= ~IO_WQ_WORK_FILES
;
5835 static void __io_clean_op(struct io_kiocb
*req
)
5837 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
5838 switch (req
->opcode
) {
5839 case IORING_OP_READV
:
5840 case IORING_OP_READ_FIXED
:
5841 case IORING_OP_READ
:
5842 kfree((void *)(unsigned long)req
->rw
.addr
);
5844 case IORING_OP_RECVMSG
:
5845 case IORING_OP_RECV
:
5846 kfree(req
->sr_msg
.kbuf
);
5849 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
5852 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
5853 switch (req
->opcode
) {
5854 case IORING_OP_READV
:
5855 case IORING_OP_READ_FIXED
:
5856 case IORING_OP_READ
:
5857 case IORING_OP_WRITEV
:
5858 case IORING_OP_WRITE_FIXED
:
5859 case IORING_OP_WRITE
: {
5860 struct io_async_rw
*io
= req
->async_data
;
5862 kfree(io
->free_iovec
);
5865 case IORING_OP_RECVMSG
:
5866 case IORING_OP_SENDMSG
: {
5867 struct io_async_msghdr
*io
= req
->async_data
;
5868 if (io
->iov
!= io
->fast_iov
)
5872 case IORING_OP_SPLICE
:
5874 io_put_file(req
, req
->splice
.file_in
,
5875 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
5877 case IORING_OP_OPENAT
:
5878 case IORING_OP_OPENAT2
:
5879 if (req
->open
.filename
)
5880 putname(req
->open
.filename
);
5883 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5886 if (req
->flags
& REQ_F_INFLIGHT
)
5887 io_req_drop_files(req
);
5890 static int io_issue_sqe(struct io_kiocb
*req
, bool force_nonblock
,
5891 struct io_comp_state
*cs
)
5893 struct io_ring_ctx
*ctx
= req
->ctx
;
5896 switch (req
->opcode
) {
5898 ret
= io_nop(req
, cs
);
5900 case IORING_OP_READV
:
5901 case IORING_OP_READ_FIXED
:
5902 case IORING_OP_READ
:
5903 ret
= io_read(req
, force_nonblock
, cs
);
5905 case IORING_OP_WRITEV
:
5906 case IORING_OP_WRITE_FIXED
:
5907 case IORING_OP_WRITE
:
5908 ret
= io_write(req
, force_nonblock
, cs
);
5910 case IORING_OP_FSYNC
:
5911 ret
= io_fsync(req
, force_nonblock
);
5913 case IORING_OP_POLL_ADD
:
5914 ret
= io_poll_add(req
);
5916 case IORING_OP_POLL_REMOVE
:
5917 ret
= io_poll_remove(req
);
5919 case IORING_OP_SYNC_FILE_RANGE
:
5920 ret
= io_sync_file_range(req
, force_nonblock
);
5922 case IORING_OP_SENDMSG
:
5923 ret
= io_sendmsg(req
, force_nonblock
, cs
);
5925 case IORING_OP_SEND
:
5926 ret
= io_send(req
, force_nonblock
, cs
);
5928 case IORING_OP_RECVMSG
:
5929 ret
= io_recvmsg(req
, force_nonblock
, cs
);
5931 case IORING_OP_RECV
:
5932 ret
= io_recv(req
, force_nonblock
, cs
);
5934 case IORING_OP_TIMEOUT
:
5935 ret
= io_timeout(req
);
5937 case IORING_OP_TIMEOUT_REMOVE
:
5938 ret
= io_timeout_remove(req
);
5940 case IORING_OP_ACCEPT
:
5941 ret
= io_accept(req
, force_nonblock
, cs
);
5943 case IORING_OP_CONNECT
:
5944 ret
= io_connect(req
, force_nonblock
, cs
);
5946 case IORING_OP_ASYNC_CANCEL
:
5947 ret
= io_async_cancel(req
);
5949 case IORING_OP_FALLOCATE
:
5950 ret
= io_fallocate(req
, force_nonblock
);
5952 case IORING_OP_OPENAT
:
5953 ret
= io_openat(req
, force_nonblock
);
5955 case IORING_OP_CLOSE
:
5956 ret
= io_close(req
, force_nonblock
, cs
);
5958 case IORING_OP_FILES_UPDATE
:
5959 ret
= io_files_update(req
, force_nonblock
, cs
);
5961 case IORING_OP_STATX
:
5962 ret
= io_statx(req
, force_nonblock
);
5964 case IORING_OP_FADVISE
:
5965 ret
= io_fadvise(req
, force_nonblock
);
5967 case IORING_OP_MADVISE
:
5968 ret
= io_madvise(req
, force_nonblock
);
5970 case IORING_OP_OPENAT2
:
5971 ret
= io_openat2(req
, force_nonblock
);
5973 case IORING_OP_EPOLL_CTL
:
5974 ret
= io_epoll_ctl(req
, force_nonblock
, cs
);
5976 case IORING_OP_SPLICE
:
5977 ret
= io_splice(req
, force_nonblock
);
5979 case IORING_OP_PROVIDE_BUFFERS
:
5980 ret
= io_provide_buffers(req
, force_nonblock
, cs
);
5982 case IORING_OP_REMOVE_BUFFERS
:
5983 ret
= io_remove_buffers(req
, force_nonblock
, cs
);
5986 ret
= io_tee(req
, force_nonblock
);
5996 /* If the op doesn't have a file, we're not polling for it */
5997 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
5998 const bool in_async
= io_wq_current_is_worker();
6000 /* workqueue context doesn't hold uring_lock, grab it now */
6002 mutex_lock(&ctx
->uring_lock
);
6004 io_iopoll_req_issued(req
);
6007 mutex_unlock(&ctx
->uring_lock
);
6013 static struct io_wq_work
*io_wq_submit_work(struct io_wq_work
*work
)
6015 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6016 struct io_kiocb
*timeout
;
6019 timeout
= io_prep_linked_timeout(req
);
6021 io_queue_linked_timeout(timeout
);
6023 /* if NO_CANCEL is set, we must still run the work */
6024 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
6025 IO_WQ_WORK_CANCEL
) {
6031 ret
= io_issue_sqe(req
, false, NULL
);
6033 * We can get EAGAIN for polled IO even though we're
6034 * forcing a sync submission from here, since we can't
6035 * wait for request slots on the block side.
6044 req_set_fail_links(req
);
6045 io_req_complete(req
, ret
);
6048 return io_steal_work(req
);
6051 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6054 struct fixed_file_table
*table
;
6056 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
6057 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
6060 static struct file
*io_file_get(struct io_submit_state
*state
,
6061 struct io_kiocb
*req
, int fd
, bool fixed
)
6063 struct io_ring_ctx
*ctx
= req
->ctx
;
6067 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6069 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6070 file
= io_file_from_index(ctx
, fd
);
6072 req
->fixed_file_refs
= &ctx
->file_data
->node
->refs
;
6073 percpu_ref_get(req
->fixed_file_refs
);
6076 trace_io_uring_file_get(ctx
, fd
);
6077 file
= __io_file_get(state
, fd
);
6083 static int io_req_set_file(struct io_submit_state
*state
, struct io_kiocb
*req
,
6088 fixed
= (req
->flags
& REQ_F_FIXED_FILE
) != 0;
6089 if (unlikely(!fixed
&& io_async_submit(req
->ctx
)))
6092 req
->file
= io_file_get(state
, req
, fd
, fixed
);
6093 if (req
->file
|| io_op_defs
[req
->opcode
].needs_file_no_error
)
6098 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6100 struct io_timeout_data
*data
= container_of(timer
,
6101 struct io_timeout_data
, timer
);
6102 struct io_kiocb
*req
= data
->req
;
6103 struct io_ring_ctx
*ctx
= req
->ctx
;
6104 struct io_kiocb
*prev
= NULL
;
6105 unsigned long flags
;
6107 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6110 * We don't expect the list to be empty, that will only happen if we
6111 * race with the completion of the linked work.
6113 if (!list_empty(&req
->link_list
)) {
6114 prev
= list_entry(req
->link_list
.prev
, struct io_kiocb
,
6116 if (refcount_inc_not_zero(&prev
->refs
))
6117 list_del_init(&req
->link_list
);
6122 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6125 req_set_fail_links(prev
);
6126 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6129 io_req_complete(req
, -ETIME
);
6131 return HRTIMER_NORESTART
;
6134 static void __io_queue_linked_timeout(struct io_kiocb
*req
)
6137 * If the list is now empty, then our linked request finished before
6138 * we got a chance to setup the timer
6140 if (!list_empty(&req
->link_list
)) {
6141 struct io_timeout_data
*data
= req
->async_data
;
6143 data
->timer
.function
= io_link_timeout_fn
;
6144 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6149 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6151 struct io_ring_ctx
*ctx
= req
->ctx
;
6153 spin_lock_irq(&ctx
->completion_lock
);
6154 __io_queue_linked_timeout(req
);
6155 spin_unlock_irq(&ctx
->completion_lock
);
6157 /* drop submission reference */
6161 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6163 struct io_kiocb
*nxt
;
6165 if (!(req
->flags
& REQ_F_LINK_HEAD
))
6167 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
6170 nxt
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
6172 if (!nxt
|| nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6175 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6176 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6180 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
)
6182 struct io_kiocb
*linked_timeout
;
6183 struct io_kiocb
*nxt
;
6184 const struct cred
*old_creds
= NULL
;
6188 linked_timeout
= io_prep_linked_timeout(req
);
6190 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
6191 (req
->work
.flags
& IO_WQ_WORK_CREDS
) &&
6192 req
->work
.identity
->creds
!= current_cred()) {
6194 revert_creds(old_creds
);
6195 if (old_creds
== req
->work
.identity
->creds
)
6196 old_creds
= NULL
; /* restored original creds */
6198 old_creds
= override_creds(req
->work
.identity
->creds
);
6201 ret
= io_issue_sqe(req
, true, cs
);
6204 * We async punt it if the file wasn't marked NOWAIT, or if the file
6205 * doesn't support non-blocking read/write attempts
6207 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6208 if (!io_arm_poll_handler(req
)) {
6211 * Queued up for async execution, worker will release
6212 * submit reference when the iocb is actually submitted.
6214 io_queue_async_work(req
);
6218 io_queue_linked_timeout(linked_timeout
);
6222 if (unlikely(ret
)) {
6223 /* un-prep timeout, so it'll be killed as any other linked */
6224 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6225 req_set_fail_links(req
);
6227 io_req_complete(req
, ret
);
6231 /* drop submission reference */
6232 nxt
= io_put_req_find_next(req
);
6234 io_queue_linked_timeout(linked_timeout
);
6239 if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6240 linked_timeout
= NULL
;
6247 revert_creds(old_creds
);
6250 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6251 struct io_comp_state
*cs
)
6255 ret
= io_req_defer(req
, sqe
);
6257 if (ret
!= -EIOCBQUEUED
) {
6259 req_set_fail_links(req
);
6261 io_req_complete(req
, ret
);
6263 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6264 if (!req
->async_data
) {
6265 ret
= io_req_defer_prep(req
, sqe
);
6271 * Never try inline submit of IOSQE_ASYNC is set, go straight
6272 * to async execution.
6274 io_req_init_async(req
);
6275 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
6276 io_queue_async_work(req
);
6279 ret
= io_req_prep(req
, sqe
);
6283 __io_queue_sqe(req
, cs
);
6287 static inline void io_queue_link_head(struct io_kiocb
*req
,
6288 struct io_comp_state
*cs
)
6290 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6292 io_req_complete(req
, -ECANCELED
);
6294 io_queue_sqe(req
, NULL
, cs
);
6297 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6298 struct io_kiocb
**link
, struct io_comp_state
*cs
)
6300 struct io_ring_ctx
*ctx
= req
->ctx
;
6304 * If we already have a head request, queue this one for async
6305 * submittal once the head completes. If we don't have a head but
6306 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6307 * submitted sync once the chain is complete. If none of those
6308 * conditions are true (normal request), then just queue it.
6311 struct io_kiocb
*head
= *link
;
6314 * Taking sequential execution of a link, draining both sides
6315 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6316 * requests in the link. So, it drains the head and the
6317 * next after the link request. The last one is done via
6318 * drain_next flag to persist the effect across calls.
6320 if (req
->flags
& REQ_F_IO_DRAIN
) {
6321 head
->flags
|= REQ_F_IO_DRAIN
;
6322 ctx
->drain_next
= 1;
6324 ret
= io_req_defer_prep(req
, sqe
);
6325 if (unlikely(ret
)) {
6326 /* fail even hard links since we don't submit */
6327 head
->flags
|= REQ_F_FAIL_LINK
;
6330 trace_io_uring_link(ctx
, req
, head
);
6331 list_add_tail(&req
->link_list
, &head
->link_list
);
6333 /* last request of a link, enqueue the link */
6334 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6335 io_queue_link_head(head
, cs
);
6339 if (unlikely(ctx
->drain_next
)) {
6340 req
->flags
|= REQ_F_IO_DRAIN
;
6341 ctx
->drain_next
= 0;
6343 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6344 req
->flags
|= REQ_F_LINK_HEAD
;
6345 INIT_LIST_HEAD(&req
->link_list
);
6347 ret
= io_req_defer_prep(req
, sqe
);
6349 req
->flags
|= REQ_F_FAIL_LINK
;
6352 io_queue_sqe(req
, sqe
, cs
);
6360 * Batched submission is done, ensure local IO is flushed out.
6362 static void io_submit_state_end(struct io_submit_state
*state
)
6364 if (!list_empty(&state
->comp
.list
))
6365 io_submit_flush_completions(&state
->comp
);
6366 blk_finish_plug(&state
->plug
);
6367 io_state_file_put(state
);
6368 if (state
->free_reqs
)
6369 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
6373 * Start submission side cache.
6375 static void io_submit_state_start(struct io_submit_state
*state
,
6376 struct io_ring_ctx
*ctx
, unsigned int max_ios
)
6378 blk_start_plug(&state
->plug
);
6380 INIT_LIST_HEAD(&state
->comp
.list
);
6381 state
->comp
.ctx
= ctx
;
6382 state
->free_reqs
= 0;
6384 state
->ios_left
= max_ios
;
6387 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6389 struct io_rings
*rings
= ctx
->rings
;
6392 * Ensure any loads from the SQEs are done at this point,
6393 * since once we write the new head, the application could
6394 * write new data to them.
6396 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6400 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6401 * that is mapped by userspace. This means that care needs to be taken to
6402 * ensure that reads are stable, as we cannot rely on userspace always
6403 * being a good citizen. If members of the sqe are validated and then later
6404 * used, it's important that those reads are done through READ_ONCE() to
6405 * prevent a re-load down the line.
6407 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6409 u32
*sq_array
= ctx
->sq_array
;
6413 * The cached sq head (or cq tail) serves two purposes:
6415 * 1) allows us to batch the cost of updating the user visible
6417 * 2) allows the kernel side to track the head on its own, even
6418 * though the application is the one updating it.
6420 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
6421 if (likely(head
< ctx
->sq_entries
))
6422 return &ctx
->sq_sqes
[head
];
6424 /* drop invalid entries */
6425 ctx
->cached_sq_dropped
++;
6426 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6430 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
6432 ctx
->cached_sq_head
++;
6436 * Check SQE restrictions (opcode and flags).
6438 * Returns 'true' if SQE is allowed, 'false' otherwise.
6440 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6441 struct io_kiocb
*req
,
6442 unsigned int sqe_flags
)
6444 if (!ctx
->restricted
)
6447 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6450 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6451 ctx
->restrictions
.sqe_flags_required
)
6454 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6455 ctx
->restrictions
.sqe_flags_required
))
6461 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6462 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6463 IOSQE_BUFFER_SELECT)
6465 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6466 const struct io_uring_sqe
*sqe
,
6467 struct io_submit_state
*state
)
6469 unsigned int sqe_flags
;
6472 req
->opcode
= READ_ONCE(sqe
->opcode
);
6473 req
->user_data
= READ_ONCE(sqe
->user_data
);
6474 req
->async_data
= NULL
;
6478 /* one is dropped after submission, the other at completion */
6479 refcount_set(&req
->refs
, 2);
6480 req
->task
= current
;
6483 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6486 if (unlikely(io_sq_thread_acquire_mm(ctx
, req
)))
6489 sqe_flags
= READ_ONCE(sqe
->flags
);
6490 /* enforce forwards compatibility on users */
6491 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6494 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6497 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6498 !io_op_defs
[req
->opcode
].buffer_select
)
6501 id
= READ_ONCE(sqe
->personality
);
6503 struct io_identity
*iod
;
6505 iod
= idr_find(&ctx
->personality_idr
, id
);
6508 refcount_inc(&iod
->count
);
6510 __io_req_init_async(req
);
6511 get_cred(iod
->creds
);
6512 req
->work
.identity
= iod
;
6513 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
6516 /* same numerical values with corresponding REQ_F_*, safe to copy */
6517 req
->flags
|= sqe_flags
;
6519 if (!io_op_defs
[req
->opcode
].needs_file
)
6522 ret
= io_req_set_file(state
, req
, READ_ONCE(sqe
->fd
));
6527 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6529 struct io_submit_state state
;
6530 struct io_kiocb
*link
= NULL
;
6531 int i
, submitted
= 0;
6533 /* if we have a backlog and couldn't flush it all, return BUSY */
6534 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6535 if (!list_empty(&ctx
->cq_overflow_list
) &&
6536 !io_cqring_overflow_flush(ctx
, false, NULL
, NULL
))
6540 /* make sure SQ entry isn't read before tail */
6541 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6543 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6546 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6547 refcount_add(nr
, ¤t
->usage
);
6549 io_submit_state_start(&state
, ctx
, nr
);
6551 for (i
= 0; i
< nr
; i
++) {
6552 const struct io_uring_sqe
*sqe
;
6553 struct io_kiocb
*req
;
6556 sqe
= io_get_sqe(ctx
);
6557 if (unlikely(!sqe
)) {
6558 io_consume_sqe(ctx
);
6561 req
= io_alloc_req(ctx
, &state
);
6562 if (unlikely(!req
)) {
6564 submitted
= -EAGAIN
;
6567 io_consume_sqe(ctx
);
6568 /* will complete beyond this point, count as submitted */
6571 err
= io_init_req(ctx
, req
, sqe
, &state
);
6572 if (unlikely(err
)) {
6575 io_req_complete(req
, err
);
6579 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6580 true, io_async_submit(ctx
));
6581 err
= io_submit_sqe(req
, sqe
, &link
, &state
.comp
);
6586 if (unlikely(submitted
!= nr
)) {
6587 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6588 struct io_uring_task
*tctx
= current
->io_uring
;
6589 int unused
= nr
- ref_used
;
6591 percpu_ref_put_many(&ctx
->refs
, unused
);
6592 percpu_counter_sub(&tctx
->inflight
, unused
);
6593 put_task_struct_many(current
, unused
);
6596 io_queue_link_head(link
, &state
.comp
);
6597 io_submit_state_end(&state
);
6599 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6600 io_commit_sqring(ctx
);
6605 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6607 /* Tell userspace we may need a wakeup call */
6608 spin_lock_irq(&ctx
->completion_lock
);
6609 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6610 spin_unlock_irq(&ctx
->completion_lock
);
6613 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6615 spin_lock_irq(&ctx
->completion_lock
);
6616 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6617 spin_unlock_irq(&ctx
->completion_lock
);
6620 static int io_sq_wake_function(struct wait_queue_entry
*wqe
, unsigned mode
,
6621 int sync
, void *key
)
6623 struct io_ring_ctx
*ctx
= container_of(wqe
, struct io_ring_ctx
, sqo_wait_entry
);
6626 ret
= autoremove_wake_function(wqe
, mode
, sync
, key
);
6628 unsigned long flags
;
6630 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6631 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6632 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6643 static enum sq_ret
__io_sq_thread(struct io_ring_ctx
*ctx
,
6644 unsigned long start_jiffies
, bool cap_entries
)
6646 unsigned long timeout
= start_jiffies
+ ctx
->sq_thread_idle
;
6647 struct io_sq_data
*sqd
= ctx
->sq_data
;
6648 unsigned int to_submit
;
6652 if (!list_empty(&ctx
->iopoll_list
)) {
6653 unsigned nr_events
= 0;
6655 mutex_lock(&ctx
->uring_lock
);
6656 if (!list_empty(&ctx
->iopoll_list
) && !need_resched())
6657 io_do_iopoll(ctx
, &nr_events
, 0);
6658 mutex_unlock(&ctx
->uring_lock
);
6661 to_submit
= io_sqring_entries(ctx
);
6664 * If submit got -EBUSY, flag us as needing the application
6665 * to enter the kernel to reap and flush events.
6667 if (!to_submit
|| ret
== -EBUSY
|| need_resched()) {
6669 * Drop cur_mm before scheduling, we can't hold it for
6670 * long periods (or over schedule()). Do this before
6671 * adding ourselves to the waitqueue, as the unuse/drop
6674 io_sq_thread_drop_mm();
6677 * We're polling. If we're within the defined idle
6678 * period, then let us spin without work before going
6679 * to sleep. The exception is if we got EBUSY doing
6680 * more IO, we should wait for the application to
6681 * reap events and wake us up.
6683 if (!list_empty(&ctx
->iopoll_list
) || need_resched() ||
6684 (!time_after(jiffies
, timeout
) && ret
!= -EBUSY
&&
6685 !percpu_ref_is_dying(&ctx
->refs
)))
6688 prepare_to_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
,
6689 TASK_INTERRUPTIBLE
);
6692 * While doing polled IO, before going to sleep, we need
6693 * to check if there are new reqs added to iopoll_list,
6694 * it is because reqs may have been punted to io worker
6695 * and will be added to iopoll_list later, hence check
6696 * the iopoll_list again.
6698 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6699 !list_empty_careful(&ctx
->iopoll_list
)) {
6700 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
6704 to_submit
= io_sqring_entries(ctx
);
6705 if (!to_submit
|| ret
== -EBUSY
)
6709 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
6710 io_ring_clear_wakeup_flag(ctx
);
6712 /* if we're handling multiple rings, cap submit size for fairness */
6713 if (cap_entries
&& to_submit
> 8)
6716 mutex_lock(&ctx
->uring_lock
);
6717 if (likely(!percpu_ref_is_dying(&ctx
->refs
)))
6718 ret
= io_submit_sqes(ctx
, to_submit
);
6719 mutex_unlock(&ctx
->uring_lock
);
6721 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
6722 wake_up(&ctx
->sqo_sq_wait
);
6724 return SQT_DID_WORK
;
6727 static void io_sqd_init_new(struct io_sq_data
*sqd
)
6729 struct io_ring_ctx
*ctx
;
6731 while (!list_empty(&sqd
->ctx_new_list
)) {
6732 ctx
= list_first_entry(&sqd
->ctx_new_list
, struct io_ring_ctx
, sqd_list
);
6733 init_wait(&ctx
->sqo_wait_entry
);
6734 ctx
->sqo_wait_entry
.func
= io_sq_wake_function
;
6735 list_move_tail(&ctx
->sqd_list
, &sqd
->ctx_list
);
6736 complete(&ctx
->sq_thread_comp
);
6740 static int io_sq_thread(void *data
)
6742 struct cgroup_subsys_state
*cur_css
= NULL
;
6743 const struct cred
*old_cred
= NULL
;
6744 struct io_sq_data
*sqd
= data
;
6745 struct io_ring_ctx
*ctx
;
6746 unsigned long start_jiffies
;
6748 start_jiffies
= jiffies
;
6749 while (!kthread_should_stop()) {
6750 enum sq_ret ret
= 0;
6754 * Any changes to the sqd lists are synchronized through the
6755 * kthread parking. This synchronizes the thread vs users,
6756 * the users are synchronized on the sqd->ctx_lock.
6758 if (kthread_should_park())
6761 if (unlikely(!list_empty(&sqd
->ctx_new_list
)))
6762 io_sqd_init_new(sqd
);
6764 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
6766 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6767 if (current
->cred
!= ctx
->creds
) {
6769 revert_creds(old_cred
);
6770 old_cred
= override_creds(ctx
->creds
);
6772 io_sq_thread_associate_blkcg(ctx
, &cur_css
);
6774 current
->loginuid
= ctx
->loginuid
;
6775 current
->sessionid
= ctx
->sessionid
;
6778 ret
|= __io_sq_thread(ctx
, start_jiffies
, cap_entries
);
6780 io_sq_thread_drop_mm();
6783 if (ret
& SQT_SPIN
) {
6786 } else if (ret
== SQT_IDLE
) {
6787 if (kthread_should_park())
6789 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6790 io_ring_set_wakeup_flag(ctx
);
6792 start_jiffies
= jiffies
;
6793 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6794 io_ring_clear_wakeup_flag(ctx
);
6801 io_sq_thread_unassociate_blkcg();
6803 revert_creds(old_cred
);
6810 struct io_wait_queue
{
6811 struct wait_queue_entry wq
;
6812 struct io_ring_ctx
*ctx
;
6814 unsigned nr_timeouts
;
6817 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
6819 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6822 * Wake up if we have enough events, or if a timeout occurred since we
6823 * started waiting. For timeouts, we always want to return to userspace,
6824 * regardless of event count.
6826 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
6827 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6830 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6831 int wake_flags
, void *key
)
6833 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6836 /* use noflush == true, as we can't safely rely on locking context */
6837 if (!io_should_wake(iowq
, true))
6840 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6843 static int io_run_task_work_sig(void)
6845 if (io_run_task_work())
6847 if (!signal_pending(current
))
6849 if (current
->jobctl
& JOBCTL_TASK_WORK
) {
6850 spin_lock_irq(¤t
->sighand
->siglock
);
6851 current
->jobctl
&= ~JOBCTL_TASK_WORK
;
6852 recalc_sigpending();
6853 spin_unlock_irq(¤t
->sighand
->siglock
);
6860 * Wait until events become available, if we don't already have some. The
6861 * application must reap them itself, as they reside on the shared cq ring.
6863 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6864 const sigset_t __user
*sig
, size_t sigsz
)
6866 struct io_wait_queue iowq
= {
6869 .func
= io_wake_function
,
6870 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6873 .to_wait
= min_events
,
6875 struct io_rings
*rings
= ctx
->rings
;
6879 if (io_cqring_events(ctx
, false) >= min_events
)
6881 if (!io_run_task_work())
6886 #ifdef CONFIG_COMPAT
6887 if (in_compat_syscall())
6888 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6892 ret
= set_user_sigmask(sig
, sigsz
);
6898 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6899 trace_io_uring_cqring_wait(ctx
, min_events
);
6901 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
6902 TASK_INTERRUPTIBLE
);
6903 /* make sure we run task_work before checking for signals */
6904 ret
= io_run_task_work_sig();
6909 if (io_should_wake(&iowq
, false))
6913 finish_wait(&ctx
->wait
, &iowq
.wq
);
6915 restore_saved_sigmask_unless(ret
== -EINTR
);
6917 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
6920 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6922 #if defined(CONFIG_UNIX)
6923 if (ctx
->ring_sock
) {
6924 struct sock
*sock
= ctx
->ring_sock
->sk
;
6925 struct sk_buff
*skb
;
6927 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
6933 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6936 file
= io_file_from_index(ctx
, i
);
6943 static void io_file_ref_kill(struct percpu_ref
*ref
)
6945 struct fixed_file_data
*data
;
6947 data
= container_of(ref
, struct fixed_file_data
, refs
);
6948 complete(&data
->done
);
6951 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6953 struct fixed_file_data
*data
= ctx
->file_data
;
6954 struct fixed_file_ref_node
*ref_node
= NULL
;
6955 unsigned nr_tables
, i
;
6960 spin_lock(&data
->lock
);
6961 if (!list_empty(&data
->ref_list
))
6962 ref_node
= list_first_entry(&data
->ref_list
,
6963 struct fixed_file_ref_node
, node
);
6964 spin_unlock(&data
->lock
);
6966 percpu_ref_kill(&ref_node
->refs
);
6968 percpu_ref_kill(&data
->refs
);
6970 /* wait for all refs nodes to complete */
6971 flush_delayed_work(&ctx
->file_put_work
);
6972 wait_for_completion(&data
->done
);
6974 __io_sqe_files_unregister(ctx
);
6975 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
6976 for (i
= 0; i
< nr_tables
; i
++)
6977 kfree(data
->table
[i
].files
);
6979 percpu_ref_exit(&data
->refs
);
6981 ctx
->file_data
= NULL
;
6982 ctx
->nr_user_files
= 0;
6986 static void io_put_sq_data(struct io_sq_data
*sqd
)
6988 if (refcount_dec_and_test(&sqd
->refs
)) {
6990 * The park is a bit of a work-around, without it we get
6991 * warning spews on shutdown with SQPOLL set and affinity
6992 * set to a single CPU.
6995 kthread_park(sqd
->thread
);
6996 kthread_stop(sqd
->thread
);
7003 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7005 struct io_ring_ctx
*ctx_attach
;
7006 struct io_sq_data
*sqd
;
7009 f
= fdget(p
->wq_fd
);
7011 return ERR_PTR(-ENXIO
);
7012 if (f
.file
->f_op
!= &io_uring_fops
) {
7014 return ERR_PTR(-EINVAL
);
7017 ctx_attach
= f
.file
->private_data
;
7018 sqd
= ctx_attach
->sq_data
;
7021 return ERR_PTR(-EINVAL
);
7024 refcount_inc(&sqd
->refs
);
7029 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
)
7031 struct io_sq_data
*sqd
;
7033 if (p
->flags
& IORING_SETUP_ATTACH_WQ
)
7034 return io_attach_sq_data(p
);
7036 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7038 return ERR_PTR(-ENOMEM
);
7040 refcount_set(&sqd
->refs
, 1);
7041 INIT_LIST_HEAD(&sqd
->ctx_list
);
7042 INIT_LIST_HEAD(&sqd
->ctx_new_list
);
7043 mutex_init(&sqd
->ctx_lock
);
7044 mutex_init(&sqd
->lock
);
7045 init_waitqueue_head(&sqd
->wait
);
7049 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7050 __releases(&sqd
->lock
)
7054 kthread_unpark(sqd
->thread
);
7055 mutex_unlock(&sqd
->lock
);
7058 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7059 __acquires(&sqd
->lock
)
7063 mutex_lock(&sqd
->lock
);
7064 kthread_park(sqd
->thread
);
7067 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
7069 struct io_sq_data
*sqd
= ctx
->sq_data
;
7074 * We may arrive here from the error branch in
7075 * io_sq_offload_create() where the kthread is created
7076 * without being waked up, thus wake it up now to make
7077 * sure the wait will complete.
7079 wake_up_process(sqd
->thread
);
7080 wait_for_completion(&ctx
->sq_thread_comp
);
7082 io_sq_thread_park(sqd
);
7085 mutex_lock(&sqd
->ctx_lock
);
7086 list_del(&ctx
->sqd_list
);
7087 mutex_unlock(&sqd
->ctx_lock
);
7090 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
7091 io_sq_thread_unpark(sqd
);
7094 io_put_sq_data(sqd
);
7095 ctx
->sq_data
= NULL
;
7099 static void io_finish_async(struct io_ring_ctx
*ctx
)
7101 io_sq_thread_stop(ctx
);
7104 io_wq_destroy(ctx
->io_wq
);
7109 #if defined(CONFIG_UNIX)
7111 * Ensure the UNIX gc is aware of our file set, so we are certain that
7112 * the io_uring can be safely unregistered on process exit, even if we have
7113 * loops in the file referencing.
7115 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7117 struct sock
*sk
= ctx
->ring_sock
->sk
;
7118 struct scm_fp_list
*fpl
;
7119 struct sk_buff
*skb
;
7122 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7126 skb
= alloc_skb(0, GFP_KERNEL
);
7135 fpl
->user
= get_uid(ctx
->user
);
7136 for (i
= 0; i
< nr
; i
++) {
7137 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7141 fpl
->fp
[nr_files
] = get_file(file
);
7142 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7147 fpl
->max
= SCM_MAX_FD
;
7148 fpl
->count
= nr_files
;
7149 UNIXCB(skb
).fp
= fpl
;
7150 skb
->destructor
= unix_destruct_scm
;
7151 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7152 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7154 for (i
= 0; i
< nr_files
; i
++)
7165 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7166 * causes regular reference counting to break down. We rely on the UNIX
7167 * garbage collection to take care of this problem for us.
7169 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7171 unsigned left
, total
;
7175 left
= ctx
->nr_user_files
;
7177 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7179 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7183 total
+= this_files
;
7189 while (total
< ctx
->nr_user_files
) {
7190 struct file
*file
= io_file_from_index(ctx
, total
);
7200 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7206 static int io_sqe_alloc_file_tables(struct fixed_file_data
*file_data
,
7207 unsigned nr_tables
, unsigned nr_files
)
7211 for (i
= 0; i
< nr_tables
; i
++) {
7212 struct fixed_file_table
*table
= &file_data
->table
[i
];
7213 unsigned this_files
;
7215 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7216 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
7220 nr_files
-= this_files
;
7226 for (i
= 0; i
< nr_tables
; i
++) {
7227 struct fixed_file_table
*table
= &file_data
->table
[i
];
7228 kfree(table
->files
);
7233 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
7235 #if defined(CONFIG_UNIX)
7236 struct sock
*sock
= ctx
->ring_sock
->sk
;
7237 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7238 struct sk_buff
*skb
;
7241 __skb_queue_head_init(&list
);
7244 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7245 * remove this entry and rearrange the file array.
7247 skb
= skb_dequeue(head
);
7249 struct scm_fp_list
*fp
;
7251 fp
= UNIXCB(skb
).fp
;
7252 for (i
= 0; i
< fp
->count
; i
++) {
7255 if (fp
->fp
[i
] != file
)
7258 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7259 left
= fp
->count
- 1 - i
;
7261 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7262 left
* sizeof(struct file
*));
7269 __skb_queue_tail(&list
, skb
);
7279 __skb_queue_tail(&list
, skb
);
7281 skb
= skb_dequeue(head
);
7284 if (skb_peek(&list
)) {
7285 spin_lock_irq(&head
->lock
);
7286 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7287 __skb_queue_tail(head
, skb
);
7288 spin_unlock_irq(&head
->lock
);
7295 struct io_file_put
{
7296 struct list_head list
;
7300 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
7302 struct fixed_file_data
*file_data
= ref_node
->file_data
;
7303 struct io_ring_ctx
*ctx
= file_data
->ctx
;
7304 struct io_file_put
*pfile
, *tmp
;
7306 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
7307 list_del(&pfile
->list
);
7308 io_ring_file_put(ctx
, pfile
->file
);
7312 spin_lock(&file_data
->lock
);
7313 list_del(&ref_node
->node
);
7314 spin_unlock(&file_data
->lock
);
7316 percpu_ref_exit(&ref_node
->refs
);
7318 percpu_ref_put(&file_data
->refs
);
7321 static void io_file_put_work(struct work_struct
*work
)
7323 struct io_ring_ctx
*ctx
;
7324 struct llist_node
*node
;
7326 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
7327 node
= llist_del_all(&ctx
->file_put_llist
);
7330 struct fixed_file_ref_node
*ref_node
;
7331 struct llist_node
*next
= node
->next
;
7333 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
7334 __io_file_put_work(ref_node
);
7339 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
7341 struct fixed_file_ref_node
*ref_node
;
7342 struct io_ring_ctx
*ctx
;
7346 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
7347 ctx
= ref_node
->file_data
->ctx
;
7349 if (percpu_ref_is_dying(&ctx
->file_data
->refs
))
7352 first_add
= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
7354 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
7356 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
7359 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
7360 struct io_ring_ctx
*ctx
)
7362 struct fixed_file_ref_node
*ref_node
;
7364 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7366 return ERR_PTR(-ENOMEM
);
7368 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
7371 return ERR_PTR(-ENOMEM
);
7373 INIT_LIST_HEAD(&ref_node
->node
);
7374 INIT_LIST_HEAD(&ref_node
->file_list
);
7375 ref_node
->file_data
= ctx
->file_data
;
7379 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
7381 percpu_ref_exit(&ref_node
->refs
);
7385 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7388 __s32 __user
*fds
= (__s32 __user
*) arg
;
7389 unsigned nr_tables
, i
;
7391 int fd
, ret
= -ENOMEM
;
7392 struct fixed_file_ref_node
*ref_node
;
7393 struct fixed_file_data
*file_data
;
7399 if (nr_args
> IORING_MAX_FIXED_FILES
)
7402 file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
7405 file_data
->ctx
= ctx
;
7406 init_completion(&file_data
->done
);
7407 INIT_LIST_HEAD(&file_data
->ref_list
);
7408 spin_lock_init(&file_data
->lock
);
7410 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7411 file_data
->table
= kcalloc(nr_tables
, sizeof(*file_data
->table
),
7413 if (!file_data
->table
)
7416 if (percpu_ref_init(&file_data
->refs
, io_file_ref_kill
,
7417 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
7420 if (io_sqe_alloc_file_tables(file_data
, nr_tables
, nr_args
))
7422 ctx
->file_data
= file_data
;
7424 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7425 struct fixed_file_table
*table
;
7428 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7432 /* allow sparse sets */
7442 * Don't allow io_uring instances to be registered. If UNIX
7443 * isn't enabled, then this causes a reference cycle and this
7444 * instance can never get freed. If UNIX is enabled we'll
7445 * handle it just fine, but there's still no point in allowing
7446 * a ring fd as it doesn't support regular read/write anyway.
7448 if (file
->f_op
== &io_uring_fops
) {
7452 table
= &file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7453 index
= i
& IORING_FILE_TABLE_MASK
;
7454 table
->files
[index
] = file
;
7457 ret
= io_sqe_files_scm(ctx
);
7459 io_sqe_files_unregister(ctx
);
7463 ref_node
= alloc_fixed_file_ref_node(ctx
);
7464 if (IS_ERR(ref_node
)) {
7465 io_sqe_files_unregister(ctx
);
7466 return PTR_ERR(ref_node
);
7469 file_data
->node
= ref_node
;
7470 spin_lock(&file_data
->lock
);
7471 list_add(&ref_node
->node
, &file_data
->ref_list
);
7472 spin_unlock(&file_data
->lock
);
7473 percpu_ref_get(&file_data
->refs
);
7476 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7477 file
= io_file_from_index(ctx
, i
);
7481 for (i
= 0; i
< nr_tables
; i
++)
7482 kfree(file_data
->table
[i
].files
);
7483 ctx
->nr_user_files
= 0;
7485 percpu_ref_exit(&file_data
->refs
);
7487 kfree(file_data
->table
);
7489 ctx
->file_data
= NULL
;
7493 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7496 #if defined(CONFIG_UNIX)
7497 struct sock
*sock
= ctx
->ring_sock
->sk
;
7498 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7499 struct sk_buff
*skb
;
7502 * See if we can merge this file into an existing skb SCM_RIGHTS
7503 * file set. If there's no room, fall back to allocating a new skb
7504 * and filling it in.
7506 spin_lock_irq(&head
->lock
);
7507 skb
= skb_peek(head
);
7509 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7511 if (fpl
->count
< SCM_MAX_FD
) {
7512 __skb_unlink(skb
, head
);
7513 spin_unlock_irq(&head
->lock
);
7514 fpl
->fp
[fpl
->count
] = get_file(file
);
7515 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7517 spin_lock_irq(&head
->lock
);
7518 __skb_queue_head(head
, skb
);
7523 spin_unlock_irq(&head
->lock
);
7530 return __io_sqe_files_scm(ctx
, 1, index
);
7536 static int io_queue_file_removal(struct fixed_file_data
*data
,
7539 struct io_file_put
*pfile
;
7540 struct fixed_file_ref_node
*ref_node
= data
->node
;
7542 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
7547 list_add(&pfile
->list
, &ref_node
->file_list
);
7552 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7553 struct io_uring_files_update
*up
,
7556 struct fixed_file_data
*data
= ctx
->file_data
;
7557 struct fixed_file_ref_node
*ref_node
;
7562 bool needs_switch
= false;
7564 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7566 if (done
> ctx
->nr_user_files
)
7569 ref_node
= alloc_fixed_file_ref_node(ctx
);
7570 if (IS_ERR(ref_node
))
7571 return PTR_ERR(ref_node
);
7574 fds
= u64_to_user_ptr(up
->fds
);
7576 struct fixed_file_table
*table
;
7580 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7584 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
7585 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7586 index
= i
& IORING_FILE_TABLE_MASK
;
7587 if (table
->files
[index
]) {
7588 file
= table
->files
[index
];
7589 err
= io_queue_file_removal(data
, file
);
7592 table
->files
[index
] = NULL
;
7593 needs_switch
= true;
7602 * Don't allow io_uring instances to be registered. If
7603 * UNIX isn't enabled, then this causes a reference
7604 * cycle and this instance can never get freed. If UNIX
7605 * is enabled we'll handle it just fine, but there's
7606 * still no point in allowing a ring fd as it doesn't
7607 * support regular read/write anyway.
7609 if (file
->f_op
== &io_uring_fops
) {
7614 table
->files
[index
] = file
;
7615 err
= io_sqe_file_register(ctx
, file
, i
);
7617 table
->files
[index
] = NULL
;
7628 percpu_ref_kill(&data
->node
->refs
);
7629 spin_lock(&data
->lock
);
7630 list_add(&ref_node
->node
, &data
->ref_list
);
7631 data
->node
= ref_node
;
7632 spin_unlock(&data
->lock
);
7633 percpu_ref_get(&ctx
->file_data
->refs
);
7635 destroy_fixed_file_ref_node(ref_node
);
7637 return done
? done
: err
;
7640 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7643 struct io_uring_files_update up
;
7645 if (!ctx
->file_data
)
7649 if (copy_from_user(&up
, arg
, sizeof(up
)))
7654 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7657 static void io_free_work(struct io_wq_work
*work
)
7659 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7661 /* Consider that io_steal_work() relies on this ref */
7665 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
7666 struct io_uring_params
*p
)
7668 struct io_wq_data data
;
7670 struct io_ring_ctx
*ctx_attach
;
7671 unsigned int concurrency
;
7674 data
.user
= ctx
->user
;
7675 data
.free_work
= io_free_work
;
7676 data
.do_work
= io_wq_submit_work
;
7678 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
7679 /* Do QD, or 4 * CPUS, whatever is smallest */
7680 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7682 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
7683 if (IS_ERR(ctx
->io_wq
)) {
7684 ret
= PTR_ERR(ctx
->io_wq
);
7690 f
= fdget(p
->wq_fd
);
7694 if (f
.file
->f_op
!= &io_uring_fops
) {
7699 ctx_attach
= f
.file
->private_data
;
7700 /* @io_wq is protected by holding the fd */
7701 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
7706 ctx
->io_wq
= ctx_attach
->io_wq
;
7712 static int io_uring_alloc_task_context(struct task_struct
*task
)
7714 struct io_uring_task
*tctx
;
7717 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
7718 if (unlikely(!tctx
))
7721 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
7722 if (unlikely(ret
)) {
7728 init_waitqueue_head(&tctx
->wait
);
7731 io_init_identity(&tctx
->__identity
);
7732 tctx
->identity
= &tctx
->__identity
;
7733 task
->io_uring
= tctx
;
7737 void __io_uring_free(struct task_struct
*tsk
)
7739 struct io_uring_task
*tctx
= tsk
->io_uring
;
7741 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
7742 WARN_ON_ONCE(refcount_read(&tctx
->identity
->count
) != 1);
7743 if (tctx
->identity
!= &tctx
->__identity
)
7744 kfree(tctx
->identity
);
7745 percpu_counter_destroy(&tctx
->inflight
);
7747 tsk
->io_uring
= NULL
;
7750 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
7751 struct io_uring_params
*p
)
7755 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7756 struct io_sq_data
*sqd
;
7759 if (!capable(CAP_SYS_ADMIN
))
7762 sqd
= io_get_sq_data(p
);
7769 io_sq_thread_park(sqd
);
7770 mutex_lock(&sqd
->ctx_lock
);
7771 list_add(&ctx
->sqd_list
, &sqd
->ctx_new_list
);
7772 mutex_unlock(&sqd
->ctx_lock
);
7773 io_sq_thread_unpark(sqd
);
7775 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
7776 if (!ctx
->sq_thread_idle
)
7777 ctx
->sq_thread_idle
= HZ
;
7782 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7783 int cpu
= p
->sq_thread_cpu
;
7786 if (cpu
>= nr_cpu_ids
)
7788 if (!cpu_online(cpu
))
7791 sqd
->thread
= kthread_create_on_cpu(io_sq_thread
, sqd
,
7792 cpu
, "io_uring-sq");
7794 sqd
->thread
= kthread_create(io_sq_thread
, sqd
,
7797 if (IS_ERR(sqd
->thread
)) {
7798 ret
= PTR_ERR(sqd
->thread
);
7802 ret
= io_uring_alloc_task_context(sqd
->thread
);
7805 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7806 /* Can't have SQ_AFF without SQPOLL */
7812 ret
= io_init_wq_offload(ctx
, p
);
7818 io_finish_async(ctx
);
7822 static void io_sq_offload_start(struct io_ring_ctx
*ctx
)
7824 struct io_sq_data
*sqd
= ctx
->sq_data
;
7826 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && sqd
->thread
)
7827 wake_up_process(sqd
->thread
);
7830 static inline void __io_unaccount_mem(struct user_struct
*user
,
7831 unsigned long nr_pages
)
7833 atomic_long_sub(nr_pages
, &user
->locked_vm
);
7836 static inline int __io_account_mem(struct user_struct
*user
,
7837 unsigned long nr_pages
)
7839 unsigned long page_limit
, cur_pages
, new_pages
;
7841 /* Don't allow more pages than we can safely lock */
7842 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
7845 cur_pages
= atomic_long_read(&user
->locked_vm
);
7846 new_pages
= cur_pages
+ nr_pages
;
7847 if (new_pages
> page_limit
)
7849 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
7850 new_pages
) != cur_pages
);
7855 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7856 enum io_mem_account acct
)
7859 __io_unaccount_mem(ctx
->user
, nr_pages
);
7861 if (ctx
->mm_account
) {
7862 if (acct
== ACCT_LOCKED
)
7863 ctx
->mm_account
->locked_vm
-= nr_pages
;
7864 else if (acct
== ACCT_PINNED
)
7865 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
7869 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7870 enum io_mem_account acct
)
7874 if (ctx
->limit_mem
) {
7875 ret
= __io_account_mem(ctx
->user
, nr_pages
);
7880 if (ctx
->mm_account
) {
7881 if (acct
== ACCT_LOCKED
)
7882 ctx
->mm_account
->locked_vm
+= nr_pages
;
7883 else if (acct
== ACCT_PINNED
)
7884 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
7890 static void io_mem_free(void *ptr
)
7897 page
= virt_to_head_page(ptr
);
7898 if (put_page_testzero(page
))
7899 free_compound_page(page
);
7902 static void *io_mem_alloc(size_t size
)
7904 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
7907 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
7910 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
7913 struct io_rings
*rings
;
7914 size_t off
, sq_array_size
;
7916 off
= struct_size(rings
, cqes
, cq_entries
);
7917 if (off
== SIZE_MAX
)
7921 off
= ALIGN(off
, SMP_CACHE_BYTES
);
7929 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
7930 if (sq_array_size
== SIZE_MAX
)
7933 if (check_add_overflow(off
, sq_array_size
, &off
))
7939 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
7943 pages
= (size_t)1 << get_order(
7944 rings_size(sq_entries
, cq_entries
, NULL
));
7945 pages
+= (size_t)1 << get_order(
7946 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
7951 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
7955 if (!ctx
->user_bufs
)
7958 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7959 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7961 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
7962 unpin_user_page(imu
->bvec
[j
].bv_page
);
7964 if (imu
->acct_pages
)
7965 io_unaccount_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
7970 kfree(ctx
->user_bufs
);
7971 ctx
->user_bufs
= NULL
;
7972 ctx
->nr_user_bufs
= 0;
7976 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
7977 void __user
*arg
, unsigned index
)
7979 struct iovec __user
*src
;
7981 #ifdef CONFIG_COMPAT
7983 struct compat_iovec __user
*ciovs
;
7984 struct compat_iovec ciov
;
7986 ciovs
= (struct compat_iovec __user
*) arg
;
7987 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
7990 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
7991 dst
->iov_len
= ciov
.iov_len
;
7995 src
= (struct iovec __user
*) arg
;
7996 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8002 * Not super efficient, but this is just a registration time. And we do cache
8003 * the last compound head, so generally we'll only do a full search if we don't
8006 * We check if the given compound head page has already been accounted, to
8007 * avoid double accounting it. This allows us to account the full size of the
8008 * page, not just the constituent pages of a huge page.
8010 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8011 int nr_pages
, struct page
*hpage
)
8015 /* check current page array */
8016 for (i
= 0; i
< nr_pages
; i
++) {
8017 if (!PageCompound(pages
[i
]))
8019 if (compound_head(pages
[i
]) == hpage
)
8023 /* check previously registered pages */
8024 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8025 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8027 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8028 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8030 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8038 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8039 int nr_pages
, struct io_mapped_ubuf
*imu
,
8040 struct page
**last_hpage
)
8044 for (i
= 0; i
< nr_pages
; i
++) {
8045 if (!PageCompound(pages
[i
])) {
8050 hpage
= compound_head(pages
[i
]);
8051 if (hpage
== *last_hpage
)
8053 *last_hpage
= hpage
;
8054 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8056 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8060 if (!imu
->acct_pages
)
8063 ret
= io_account_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8065 imu
->acct_pages
= 0;
8069 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8072 struct vm_area_struct
**vmas
= NULL
;
8073 struct page
**pages
= NULL
;
8074 struct page
*last_hpage
= NULL
;
8075 int i
, j
, got_pages
= 0;
8080 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8083 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
8085 if (!ctx
->user_bufs
)
8088 for (i
= 0; i
< nr_args
; i
++) {
8089 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8090 unsigned long off
, start
, end
, ubuf
;
8095 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8100 * Don't impose further limits on the size and buffer
8101 * constraints here, we'll -EINVAL later when IO is
8102 * submitted if they are wrong.
8105 if (!iov
.iov_base
|| !iov
.iov_len
)
8108 /* arbitrary limit, but we need something */
8109 if (iov
.iov_len
> SZ_1G
)
8112 ubuf
= (unsigned long) iov
.iov_base
;
8113 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8114 start
= ubuf
>> PAGE_SHIFT
;
8115 nr_pages
= end
- start
;
8118 if (!pages
|| nr_pages
> got_pages
) {
8121 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
8123 vmas
= kvmalloc_array(nr_pages
,
8124 sizeof(struct vm_area_struct
*),
8126 if (!pages
|| !vmas
) {
8130 got_pages
= nr_pages
;
8133 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8140 mmap_read_lock(current
->mm
);
8141 pret
= pin_user_pages(ubuf
, nr_pages
,
8142 FOLL_WRITE
| FOLL_LONGTERM
,
8144 if (pret
== nr_pages
) {
8145 /* don't support file backed memory */
8146 for (j
= 0; j
< nr_pages
; j
++) {
8147 struct vm_area_struct
*vma
= vmas
[j
];
8150 !is_file_hugepages(vma
->vm_file
)) {
8156 ret
= pret
< 0 ? pret
: -EFAULT
;
8158 mmap_read_unlock(current
->mm
);
8161 * if we did partial map, or found file backed vmas,
8162 * release any pages we did get
8165 unpin_user_pages(pages
, pret
);
8170 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, &last_hpage
);
8172 unpin_user_pages(pages
, pret
);
8177 off
= ubuf
& ~PAGE_MASK
;
8179 for (j
= 0; j
< nr_pages
; j
++) {
8182 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8183 imu
->bvec
[j
].bv_page
= pages
[j
];
8184 imu
->bvec
[j
].bv_len
= vec_len
;
8185 imu
->bvec
[j
].bv_offset
= off
;
8189 /* store original address for later verification */
8191 imu
->len
= iov
.iov_len
;
8192 imu
->nr_bvecs
= nr_pages
;
8194 ctx
->nr_user_bufs
++;
8202 io_sqe_buffer_unregister(ctx
);
8206 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8208 __s32 __user
*fds
= arg
;
8214 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8217 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8218 if (IS_ERR(ctx
->cq_ev_fd
)) {
8219 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8220 ctx
->cq_ev_fd
= NULL
;
8227 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8229 if (ctx
->cq_ev_fd
) {
8230 eventfd_ctx_put(ctx
->cq_ev_fd
);
8231 ctx
->cq_ev_fd
= NULL
;
8238 static int __io_destroy_buffers(int id
, void *p
, void *data
)
8240 struct io_ring_ctx
*ctx
= data
;
8241 struct io_buffer
*buf
= p
;
8243 __io_remove_buffers(ctx
, buf
, id
, -1U);
8247 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8249 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
8250 idr_destroy(&ctx
->io_buffer_idr
);
8253 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8255 io_finish_async(ctx
);
8256 io_sqe_buffer_unregister(ctx
);
8258 if (ctx
->sqo_task
) {
8259 put_task_struct(ctx
->sqo_task
);
8260 ctx
->sqo_task
= NULL
;
8261 mmdrop(ctx
->mm_account
);
8262 ctx
->mm_account
= NULL
;
8265 #ifdef CONFIG_BLK_CGROUP
8266 if (ctx
->sqo_blkcg_css
)
8267 css_put(ctx
->sqo_blkcg_css
);
8270 io_sqe_files_unregister(ctx
);
8271 io_eventfd_unregister(ctx
);
8272 io_destroy_buffers(ctx
);
8273 idr_destroy(&ctx
->personality_idr
);
8275 #if defined(CONFIG_UNIX)
8276 if (ctx
->ring_sock
) {
8277 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8278 sock_release(ctx
->ring_sock
);
8282 io_mem_free(ctx
->rings
);
8283 io_mem_free(ctx
->sq_sqes
);
8285 percpu_ref_exit(&ctx
->refs
);
8286 free_uid(ctx
->user
);
8287 put_cred(ctx
->creds
);
8288 kfree(ctx
->cancel_hash
);
8289 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
8293 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8295 struct io_ring_ctx
*ctx
= file
->private_data
;
8298 poll_wait(file
, &ctx
->cq_wait
, wait
);
8300 * synchronizes with barrier from wq_has_sleeper call in
8304 if (!io_sqring_full(ctx
))
8305 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8306 if (io_cqring_events(ctx
, false))
8307 mask
|= EPOLLIN
| EPOLLRDNORM
;
8312 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8314 struct io_ring_ctx
*ctx
= file
->private_data
;
8316 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8319 static int io_remove_personalities(int id
, void *p
, void *data
)
8321 struct io_ring_ctx
*ctx
= data
;
8322 struct io_identity
*iod
;
8324 iod
= idr_remove(&ctx
->personality_idr
, id
);
8326 put_cred(iod
->creds
);
8327 if (refcount_dec_and_test(&iod
->count
))
8333 static void io_ring_exit_work(struct work_struct
*work
)
8335 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
8339 * If we're doing polled IO and end up having requests being
8340 * submitted async (out-of-line), then completions can come in while
8341 * we're waiting for refs to drop. We need to reap these manually,
8342 * as nobody else will be looking for them.
8346 io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8347 io_iopoll_try_reap_events(ctx
);
8348 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8349 io_ring_ctx_free(ctx
);
8352 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8354 mutex_lock(&ctx
->uring_lock
);
8355 percpu_ref_kill(&ctx
->refs
);
8356 mutex_unlock(&ctx
->uring_lock
);
8358 io_kill_timeouts(ctx
, NULL
);
8359 io_poll_remove_all(ctx
, NULL
);
8362 io_wq_cancel_all(ctx
->io_wq
);
8364 /* if we failed setting up the ctx, we might not have any rings */
8366 io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8367 io_iopoll_try_reap_events(ctx
);
8368 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
8371 * Do this upfront, so we won't have a grace period where the ring
8372 * is closed but resources aren't reaped yet. This can cause
8373 * spurious failure in setting up a new ring.
8375 io_unaccount_mem(ctx
, ring_pages(ctx
->sq_entries
, ctx
->cq_entries
),
8378 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8380 * Use system_unbound_wq to avoid spawning tons of event kworkers
8381 * if we're exiting a ton of rings at the same time. It just adds
8382 * noise and overhead, there's no discernable change in runtime
8383 * over using system_wq.
8385 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8388 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8390 struct io_ring_ctx
*ctx
= file
->private_data
;
8392 file
->private_data
= NULL
;
8393 io_ring_ctx_wait_and_kill(ctx
);
8397 static bool io_wq_files_match(struct io_wq_work
*work
, void *data
)
8399 struct files_struct
*files
= data
;
8401 return !files
|| ((work
->flags
& IO_WQ_WORK_FILES
) &&
8402 work
->identity
->files
== files
);
8406 * Returns true if 'preq' is the link parent of 'req'
8408 static bool io_match_link(struct io_kiocb
*preq
, struct io_kiocb
*req
)
8410 struct io_kiocb
*link
;
8412 if (!(preq
->flags
& REQ_F_LINK_HEAD
))
8415 list_for_each_entry(link
, &preq
->link_list
, link_list
) {
8423 static bool io_match_link_files(struct io_kiocb
*req
,
8424 struct files_struct
*files
)
8426 struct io_kiocb
*link
;
8428 if (io_match_files(req
, files
))
8430 if (req
->flags
& REQ_F_LINK_HEAD
) {
8431 list_for_each_entry(link
, &req
->link_list
, link_list
) {
8432 if (io_match_files(link
, files
))
8440 * We're looking to cancel 'req' because it's holding on to our files, but
8441 * 'req' could be a link to another request. See if it is, and cancel that
8442 * parent request if so.
8444 static bool io_poll_remove_link(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
)
8446 struct hlist_node
*tmp
;
8447 struct io_kiocb
*preq
;
8451 spin_lock_irq(&ctx
->completion_lock
);
8452 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
8453 struct hlist_head
*list
;
8455 list
= &ctx
->cancel_hash
[i
];
8456 hlist_for_each_entry_safe(preq
, tmp
, list
, hash_node
) {
8457 found
= io_match_link(preq
, req
);
8459 io_poll_remove_one(preq
);
8464 spin_unlock_irq(&ctx
->completion_lock
);
8468 static bool io_timeout_remove_link(struct io_ring_ctx
*ctx
,
8469 struct io_kiocb
*req
)
8471 struct io_kiocb
*preq
;
8474 spin_lock_irq(&ctx
->completion_lock
);
8475 list_for_each_entry(preq
, &ctx
->timeout_list
, timeout
.list
) {
8476 found
= io_match_link(preq
, req
);
8478 __io_timeout_cancel(preq
);
8482 spin_unlock_irq(&ctx
->completion_lock
);
8486 static bool io_cancel_link_cb(struct io_wq_work
*work
, void *data
)
8488 return io_match_link(container_of(work
, struct io_kiocb
, work
), data
);
8491 static void io_attempt_cancel(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
)
8493 enum io_wq_cancel cret
;
8495 /* cancel this particular work, if it's running */
8496 cret
= io_wq_cancel_work(ctx
->io_wq
, &req
->work
);
8497 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8500 /* find links that hold this pending, cancel those */
8501 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_link_cb
, req
, true);
8502 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8505 /* if we have a poll link holding this pending, cancel that */
8506 if (io_poll_remove_link(ctx
, req
))
8509 /* final option, timeout link is holding this req pending */
8510 io_timeout_remove_link(ctx
, req
);
8513 static void io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8514 struct files_struct
*files
)
8516 struct io_defer_entry
*de
= NULL
;
8519 spin_lock_irq(&ctx
->completion_lock
);
8520 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8521 if (io_match_link_files(de
->req
, files
)) {
8522 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8526 spin_unlock_irq(&ctx
->completion_lock
);
8528 while (!list_empty(&list
)) {
8529 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8530 list_del_init(&de
->list
);
8531 req_set_fail_links(de
->req
);
8532 io_put_req(de
->req
);
8533 io_req_complete(de
->req
, -ECANCELED
);
8539 * Returns true if we found and killed one or more files pinning requests
8541 static bool io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8542 struct files_struct
*files
)
8544 if (list_empty_careful(&ctx
->inflight_list
))
8547 io_cancel_defer_files(ctx
, files
);
8548 /* cancel all at once, should be faster than doing it one by one*/
8549 io_wq_cancel_cb(ctx
->io_wq
, io_wq_files_match
, files
, true);
8551 while (!list_empty_careful(&ctx
->inflight_list
)) {
8552 struct io_kiocb
*cancel_req
= NULL
, *req
;
8555 spin_lock_irq(&ctx
->inflight_lock
);
8556 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
8557 if (files
&& (req
->work
.flags
& IO_WQ_WORK_FILES
) &&
8558 req
->work
.identity
->files
!= files
)
8560 /* req is being completed, ignore */
8561 if (!refcount_inc_not_zero(&req
->refs
))
8567 prepare_to_wait(&ctx
->inflight_wait
, &wait
,
8568 TASK_UNINTERRUPTIBLE
);
8569 spin_unlock_irq(&ctx
->inflight_lock
);
8571 /* We need to keep going until we don't find a matching req */
8574 /* cancel this request, or head link requests */
8575 io_attempt_cancel(ctx
, cancel_req
);
8576 io_put_req(cancel_req
);
8577 /* cancellations _may_ trigger task work */
8580 finish_wait(&ctx
->inflight_wait
, &wait
);
8586 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8588 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8589 struct task_struct
*task
= data
;
8591 return io_task_match(req
, task
);
8594 static bool __io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8595 struct task_struct
*task
,
8596 struct files_struct
*files
)
8600 ret
= io_uring_cancel_files(ctx
, files
);
8602 enum io_wq_cancel cret
;
8604 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, task
, true);
8605 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8608 /* SQPOLL thread does its own polling */
8609 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8610 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8611 io_iopoll_try_reap_events(ctx
);
8616 ret
|= io_poll_remove_all(ctx
, task
);
8617 ret
|= io_kill_timeouts(ctx
, task
);
8624 * We need to iteratively cancel requests, in case a request has dependent
8625 * hard links. These persist even for failure of cancelations, hence keep
8626 * looping until none are found.
8628 static void io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8629 struct files_struct
*files
)
8631 struct task_struct
*task
= current
;
8633 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
)
8634 task
= ctx
->sq_data
->thread
;
8636 io_cqring_overflow_flush(ctx
, true, task
, files
);
8638 while (__io_uring_cancel_task_requests(ctx
, task
, files
)) {
8645 * Note that this task has used io_uring. We use it for cancelation purposes.
8647 static int io_uring_add_task_file(struct file
*file
)
8649 struct io_uring_task
*tctx
= current
->io_uring
;
8651 if (unlikely(!tctx
)) {
8654 ret
= io_uring_alloc_task_context(current
);
8657 tctx
= current
->io_uring
;
8659 if (tctx
->last
!= file
) {
8660 void *old
= xa_load(&tctx
->xa
, (unsigned long)file
);
8664 xa_store(&tctx
->xa
, (unsigned long)file
, file
, GFP_KERNEL
);
8673 * Remove this io_uring_file -> task mapping.
8675 static void io_uring_del_task_file(struct file
*file
)
8677 struct io_uring_task
*tctx
= current
->io_uring
;
8679 if (tctx
->last
== file
)
8681 file
= xa_erase(&tctx
->xa
, (unsigned long)file
);
8687 * Drop task note for this file if we're the only ones that hold it after
8690 static void io_uring_attempt_task_drop(struct file
*file
)
8692 if (!current
->io_uring
)
8695 * fput() is pending, will be 2 if the only other ref is our potential
8696 * task file note. If the task is exiting, drop regardless of count.
8698 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
) ||
8699 atomic_long_read(&file
->f_count
) == 2)
8700 io_uring_del_task_file(file
);
8703 void __io_uring_files_cancel(struct files_struct
*files
)
8705 struct io_uring_task
*tctx
= current
->io_uring
;
8707 unsigned long index
;
8709 /* make sure overflow events are dropped */
8710 tctx
->in_idle
= true;
8712 xa_for_each(&tctx
->xa
, index
, file
) {
8713 struct io_ring_ctx
*ctx
= file
->private_data
;
8715 io_uring_cancel_task_requests(ctx
, files
);
8717 io_uring_del_task_file(file
);
8722 * Find any io_uring fd that this task has registered or done IO on, and cancel
8725 void __io_uring_task_cancel(void)
8727 struct io_uring_task
*tctx
= current
->io_uring
;
8731 /* make sure overflow events are dropped */
8732 tctx
->in_idle
= true;
8735 /* read completions before cancelations */
8736 inflight
= percpu_counter_sum(&tctx
->inflight
);
8739 __io_uring_files_cancel(NULL
);
8741 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
8744 * If we've seen completions, retry. This avoids a race where
8745 * a completion comes in before we did prepare_to_wait().
8747 if (inflight
!= percpu_counter_sum(&tctx
->inflight
))
8752 finish_wait(&tctx
->wait
, &wait
);
8753 tctx
->in_idle
= false;
8756 static int io_uring_flush(struct file
*file
, void *data
)
8758 io_uring_attempt_task_drop(file
);
8762 static void *io_uring_validate_mmap_request(struct file
*file
,
8763 loff_t pgoff
, size_t sz
)
8765 struct io_ring_ctx
*ctx
= file
->private_data
;
8766 loff_t offset
= pgoff
<< PAGE_SHIFT
;
8771 case IORING_OFF_SQ_RING
:
8772 case IORING_OFF_CQ_RING
:
8775 case IORING_OFF_SQES
:
8779 return ERR_PTR(-EINVAL
);
8782 page
= virt_to_head_page(ptr
);
8783 if (sz
> page_size(page
))
8784 return ERR_PTR(-EINVAL
);
8791 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
8793 size_t sz
= vma
->vm_end
- vma
->vm_start
;
8797 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
8799 return PTR_ERR(ptr
);
8801 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
8802 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
8805 #else /* !CONFIG_MMU */
8807 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
8809 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
8812 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
8814 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
8817 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
8818 unsigned long addr
, unsigned long len
,
8819 unsigned long pgoff
, unsigned long flags
)
8823 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
8825 return PTR_ERR(ptr
);
8827 return (unsigned long) ptr
;
8830 #endif /* !CONFIG_MMU */
8832 static void io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
8837 if (!io_sqring_full(ctx
))
8840 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
8842 if (!io_sqring_full(ctx
))
8846 } while (!signal_pending(current
));
8848 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
8851 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
8852 u32
, min_complete
, u32
, flags
, const sigset_t __user
*, sig
,
8855 struct io_ring_ctx
*ctx
;
8862 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
8863 IORING_ENTER_SQ_WAIT
))
8871 if (f
.file
->f_op
!= &io_uring_fops
)
8875 ctx
= f
.file
->private_data
;
8876 if (!percpu_ref_tryget(&ctx
->refs
))
8880 if (ctx
->flags
& IORING_SETUP_R_DISABLED
)
8884 * For SQ polling, the thread will do all submissions and completions.
8885 * Just return the requested submit count, and wake the thread if
8889 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8890 if (!list_empty_careful(&ctx
->cq_overflow_list
))
8891 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
8892 if (flags
& IORING_ENTER_SQ_WAKEUP
)
8893 wake_up(&ctx
->sq_data
->wait
);
8894 if (flags
& IORING_ENTER_SQ_WAIT
)
8895 io_sqpoll_wait_sq(ctx
);
8896 submitted
= to_submit
;
8897 } else if (to_submit
) {
8898 ret
= io_uring_add_task_file(f
.file
);
8901 mutex_lock(&ctx
->uring_lock
);
8902 submitted
= io_submit_sqes(ctx
, to_submit
);
8903 mutex_unlock(&ctx
->uring_lock
);
8905 if (submitted
!= to_submit
)
8908 if (flags
& IORING_ENTER_GETEVENTS
) {
8909 min_complete
= min(min_complete
, ctx
->cq_entries
);
8912 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
8913 * space applications don't need to do io completion events
8914 * polling again, they can rely on io_sq_thread to do polling
8915 * work, which can reduce cpu usage and uring_lock contention.
8917 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
8918 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8919 ret
= io_iopoll_check(ctx
, min_complete
);
8921 ret
= io_cqring_wait(ctx
, min_complete
, sig
, sigsz
);
8926 percpu_ref_put(&ctx
->refs
);
8929 return submitted
? submitted
: ret
;
8932 #ifdef CONFIG_PROC_FS
8933 static int io_uring_show_cred(int id
, void *p
, void *data
)
8935 const struct cred
*cred
= p
;
8936 struct seq_file
*m
= data
;
8937 struct user_namespace
*uns
= seq_user_ns(m
);
8938 struct group_info
*gi
;
8943 seq_printf(m
, "%5d\n", id
);
8944 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
8945 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
8946 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
8947 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
8948 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
8949 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
8950 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
8951 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
8952 seq_puts(m
, "\n\tGroups:\t");
8953 gi
= cred
->group_info
;
8954 for (g
= 0; g
< gi
->ngroups
; g
++) {
8955 seq_put_decimal_ull(m
, g
? " " : "",
8956 from_kgid_munged(uns
, gi
->gid
[g
]));
8958 seq_puts(m
, "\n\tCapEff:\t");
8959 cap
= cred
->cap_effective
;
8960 CAP_FOR_EACH_U32(__capi
)
8961 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
8966 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
8968 struct io_sq_data
*sq
= NULL
;
8973 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
8974 * since fdinfo case grabs it in the opposite direction of normal use
8975 * cases. If we fail to get the lock, we just don't iterate any
8976 * structures that could be going away outside the io_uring mutex.
8978 has_lock
= mutex_trylock(&ctx
->uring_lock
);
8980 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
8983 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
8984 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
8985 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
8986 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
8987 struct fixed_file_table
*table
;
8990 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
8991 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
8993 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
8995 seq_printf(m
, "%5u: <none>\n", i
);
8997 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
8998 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
8999 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
9001 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
9002 (unsigned int) buf
->len
);
9004 if (has_lock
&& !idr_is_empty(&ctx
->personality_idr
)) {
9005 seq_printf(m
, "Personalities:\n");
9006 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
9008 seq_printf(m
, "PollList:\n");
9009 spin_lock_irq(&ctx
->completion_lock
);
9010 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9011 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9012 struct io_kiocb
*req
;
9014 hlist_for_each_entry(req
, list
, hash_node
)
9015 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9016 req
->task
->task_works
!= NULL
);
9018 spin_unlock_irq(&ctx
->completion_lock
);
9020 mutex_unlock(&ctx
->uring_lock
);
9023 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9025 struct io_ring_ctx
*ctx
= f
->private_data
;
9027 if (percpu_ref_tryget(&ctx
->refs
)) {
9028 __io_uring_show_fdinfo(ctx
, m
);
9029 percpu_ref_put(&ctx
->refs
);
9034 static const struct file_operations io_uring_fops
= {
9035 .release
= io_uring_release
,
9036 .flush
= io_uring_flush
,
9037 .mmap
= io_uring_mmap
,
9039 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9040 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9042 .poll
= io_uring_poll
,
9043 .fasync
= io_uring_fasync
,
9044 #ifdef CONFIG_PROC_FS
9045 .show_fdinfo
= io_uring_show_fdinfo
,
9049 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9050 struct io_uring_params
*p
)
9052 struct io_rings
*rings
;
9053 size_t size
, sq_array_offset
;
9055 /* make sure these are sane, as we already accounted them */
9056 ctx
->sq_entries
= p
->sq_entries
;
9057 ctx
->cq_entries
= p
->cq_entries
;
9059 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9060 if (size
== SIZE_MAX
)
9063 rings
= io_mem_alloc(size
);
9068 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9069 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9070 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9071 rings
->sq_ring_entries
= p
->sq_entries
;
9072 rings
->cq_ring_entries
= p
->cq_entries
;
9073 ctx
->sq_mask
= rings
->sq_ring_mask
;
9074 ctx
->cq_mask
= rings
->cq_ring_mask
;
9076 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9077 if (size
== SIZE_MAX
) {
9078 io_mem_free(ctx
->rings
);
9083 ctx
->sq_sqes
= io_mem_alloc(size
);
9084 if (!ctx
->sq_sqes
) {
9085 io_mem_free(ctx
->rings
);
9094 * Allocate an anonymous fd, this is what constitutes the application
9095 * visible backing of an io_uring instance. The application mmaps this
9096 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9097 * we have to tie this fd to a socket for file garbage collection purposes.
9099 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
9104 #if defined(CONFIG_UNIX)
9105 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9111 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9115 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9116 O_RDWR
| O_CLOEXEC
);
9120 ret
= PTR_ERR(file
);
9124 #if defined(CONFIG_UNIX)
9125 ctx
->ring_sock
->file
= file
;
9127 if (unlikely(io_uring_add_task_file(file
))) {
9128 file
= ERR_PTR(-ENOMEM
);
9131 fd_install(ret
, file
);
9134 #if defined(CONFIG_UNIX)
9135 sock_release(ctx
->ring_sock
);
9136 ctx
->ring_sock
= NULL
;
9141 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9142 struct io_uring_params __user
*params
)
9144 struct user_struct
*user
= NULL
;
9145 struct io_ring_ctx
*ctx
;
9151 if (entries
> IORING_MAX_ENTRIES
) {
9152 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9154 entries
= IORING_MAX_ENTRIES
;
9158 * Use twice as many entries for the CQ ring. It's possible for the
9159 * application to drive a higher depth than the size of the SQ ring,
9160 * since the sqes are only used at submission time. This allows for
9161 * some flexibility in overcommitting a bit. If the application has
9162 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9163 * of CQ ring entries manually.
9165 p
->sq_entries
= roundup_pow_of_two(entries
);
9166 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9168 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9169 * to a power-of-two, if it isn't already. We do NOT impose
9170 * any cq vs sq ring sizing.
9172 if (p
->cq_entries
< p
->sq_entries
)
9174 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9175 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9177 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9179 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9181 p
->cq_entries
= 2 * p
->sq_entries
;
9184 user
= get_uid(current_user());
9185 limit_mem
= !capable(CAP_IPC_LOCK
);
9188 ret
= __io_account_mem(user
,
9189 ring_pages(p
->sq_entries
, p
->cq_entries
));
9196 ctx
= io_ring_ctx_alloc(p
);
9199 __io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
9204 ctx
->compat
= in_compat_syscall();
9206 ctx
->creds
= get_current_cred();
9208 ctx
->loginuid
= current
->loginuid
;
9209 ctx
->sessionid
= current
->sessionid
;
9211 ctx
->sqo_task
= get_task_struct(current
);
9214 * This is just grabbed for accounting purposes. When a process exits,
9215 * the mm is exited and dropped before the files, hence we need to hang
9216 * on to this mm purely for the purposes of being able to unaccount
9217 * memory (locked/pinned vm). It's not used for anything else.
9219 mmgrab(current
->mm
);
9220 ctx
->mm_account
= current
->mm
;
9222 #ifdef CONFIG_BLK_CGROUP
9224 * The sq thread will belong to the original cgroup it was inited in.
9225 * If the cgroup goes offline (e.g. disabling the io controller), then
9226 * issued bios will be associated with the closest cgroup later in the
9230 ctx
->sqo_blkcg_css
= blkcg_css();
9231 ret
= css_tryget_online(ctx
->sqo_blkcg_css
);
9234 /* don't init against a dying cgroup, have the user try again */
9235 ctx
->sqo_blkcg_css
= NULL
;
9242 * Account memory _before_ installing the file descriptor. Once
9243 * the descriptor is installed, it can get closed at any time. Also
9244 * do this before hitting the general error path, as ring freeing
9245 * will un-account as well.
9247 io_account_mem(ctx
, ring_pages(p
->sq_entries
, p
->cq_entries
),
9249 ctx
->limit_mem
= limit_mem
;
9251 ret
= io_allocate_scq_urings(ctx
, p
);
9255 ret
= io_sq_offload_create(ctx
, p
);
9259 if (!(p
->flags
& IORING_SETUP_R_DISABLED
))
9260 io_sq_offload_start(ctx
);
9262 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9263 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9264 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9265 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9266 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9267 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9268 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9269 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9271 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9272 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9273 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9274 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9275 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9276 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9277 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9278 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9280 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9281 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9282 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9283 IORING_FEAT_POLL_32BITS
;
9285 if (copy_to_user(params
, p
, sizeof(*p
))) {
9291 * Install ring fd as the very last thing, so we don't risk someone
9292 * having closed it before we finish setup
9294 ret
= io_uring_get_fd(ctx
);
9298 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9301 io_ring_ctx_wait_and_kill(ctx
);
9306 * Sets up an aio uring context, and returns the fd. Applications asks for a
9307 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9308 * params structure passed in.
9310 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9312 struct io_uring_params p
;
9315 if (copy_from_user(&p
, params
, sizeof(p
)))
9317 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9322 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9323 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9324 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9325 IORING_SETUP_R_DISABLED
))
9328 return io_uring_create(entries
, &p
, params
);
9331 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9332 struct io_uring_params __user
*, params
)
9334 return io_uring_setup(entries
, params
);
9337 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9339 struct io_uring_probe
*p
;
9343 size
= struct_size(p
, ops
, nr_args
);
9344 if (size
== SIZE_MAX
)
9346 p
= kzalloc(size
, GFP_KERNEL
);
9351 if (copy_from_user(p
, arg
, size
))
9354 if (memchr_inv(p
, 0, size
))
9357 p
->last_op
= IORING_OP_LAST
- 1;
9358 if (nr_args
> IORING_OP_LAST
)
9359 nr_args
= IORING_OP_LAST
;
9361 for (i
= 0; i
< nr_args
; i
++) {
9363 if (!io_op_defs
[i
].not_supported
)
9364 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9369 if (copy_to_user(arg
, p
, size
))
9376 static int io_register_personality(struct io_ring_ctx
*ctx
)
9378 struct io_identity
*id
;
9381 id
= kmalloc(sizeof(*id
), GFP_KERNEL
);
9385 io_init_identity(id
);
9386 id
->creds
= get_current_cred();
9388 ret
= idr_alloc_cyclic(&ctx
->personality_idr
, id
, 1, USHRT_MAX
, GFP_KERNEL
);
9390 put_cred(id
->creds
);
9396 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
9398 struct io_identity
*iod
;
9400 iod
= idr_remove(&ctx
->personality_idr
, id
);
9402 put_cred(iod
->creds
);
9403 if (refcount_dec_and_test(&iod
->count
))
9411 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9412 unsigned int nr_args
)
9414 struct io_uring_restriction
*res
;
9418 /* Restrictions allowed only if rings started disabled */
9419 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9422 /* We allow only a single restrictions registration */
9423 if (ctx
->restrictions
.registered
)
9426 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9429 size
= array_size(nr_args
, sizeof(*res
));
9430 if (size
== SIZE_MAX
)
9433 res
= memdup_user(arg
, size
);
9435 return PTR_ERR(res
);
9439 for (i
= 0; i
< nr_args
; i
++) {
9440 switch (res
[i
].opcode
) {
9441 case IORING_RESTRICTION_REGISTER_OP
:
9442 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9447 __set_bit(res
[i
].register_op
,
9448 ctx
->restrictions
.register_op
);
9450 case IORING_RESTRICTION_SQE_OP
:
9451 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9456 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9458 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9459 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9461 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9462 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9471 /* Reset all restrictions if an error happened */
9473 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9475 ctx
->restrictions
.registered
= true;
9481 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9483 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9486 if (ctx
->restrictions
.registered
)
9487 ctx
->restricted
= 1;
9489 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9491 io_sq_offload_start(ctx
);
9496 static bool io_register_op_must_quiesce(int op
)
9499 case IORING_UNREGISTER_FILES
:
9500 case IORING_REGISTER_FILES_UPDATE
:
9501 case IORING_REGISTER_PROBE
:
9502 case IORING_REGISTER_PERSONALITY
:
9503 case IORING_UNREGISTER_PERSONALITY
:
9510 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
9511 void __user
*arg
, unsigned nr_args
)
9512 __releases(ctx
->uring_lock
)
9513 __acquires(ctx
->uring_lock
)
9518 * We're inside the ring mutex, if the ref is already dying, then
9519 * someone else killed the ctx or is already going through
9520 * io_uring_register().
9522 if (percpu_ref_is_dying(&ctx
->refs
))
9525 if (io_register_op_must_quiesce(opcode
)) {
9526 percpu_ref_kill(&ctx
->refs
);
9529 * Drop uring mutex before waiting for references to exit. If
9530 * another thread is currently inside io_uring_enter() it might
9531 * need to grab the uring_lock to make progress. If we hold it
9532 * here across the drain wait, then we can deadlock. It's safe
9533 * to drop the mutex here, since no new references will come in
9534 * after we've killed the percpu ref.
9536 mutex_unlock(&ctx
->uring_lock
);
9538 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
9541 ret
= io_run_task_work_sig();
9546 mutex_lock(&ctx
->uring_lock
);
9549 percpu_ref_resurrect(&ctx
->refs
);
9554 if (ctx
->restricted
) {
9555 if (opcode
>= IORING_REGISTER_LAST
) {
9560 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
9567 case IORING_REGISTER_BUFFERS
:
9568 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
9570 case IORING_UNREGISTER_BUFFERS
:
9574 ret
= io_sqe_buffer_unregister(ctx
);
9576 case IORING_REGISTER_FILES
:
9577 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
9579 case IORING_UNREGISTER_FILES
:
9583 ret
= io_sqe_files_unregister(ctx
);
9585 case IORING_REGISTER_FILES_UPDATE
:
9586 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
9588 case IORING_REGISTER_EVENTFD
:
9589 case IORING_REGISTER_EVENTFD_ASYNC
:
9593 ret
= io_eventfd_register(ctx
, arg
);
9596 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
9597 ctx
->eventfd_async
= 1;
9599 ctx
->eventfd_async
= 0;
9601 case IORING_UNREGISTER_EVENTFD
:
9605 ret
= io_eventfd_unregister(ctx
);
9607 case IORING_REGISTER_PROBE
:
9609 if (!arg
|| nr_args
> 256)
9611 ret
= io_probe(ctx
, arg
, nr_args
);
9613 case IORING_REGISTER_PERSONALITY
:
9617 ret
= io_register_personality(ctx
);
9619 case IORING_UNREGISTER_PERSONALITY
:
9623 ret
= io_unregister_personality(ctx
, nr_args
);
9625 case IORING_REGISTER_ENABLE_RINGS
:
9629 ret
= io_register_enable_rings(ctx
);
9631 case IORING_REGISTER_RESTRICTIONS
:
9632 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
9640 if (io_register_op_must_quiesce(opcode
)) {
9641 /* bring the ctx back to life */
9642 percpu_ref_reinit(&ctx
->refs
);
9644 reinit_completion(&ctx
->ref_comp
);
9649 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
9650 void __user
*, arg
, unsigned int, nr_args
)
9652 struct io_ring_ctx
*ctx
;
9661 if (f
.file
->f_op
!= &io_uring_fops
)
9664 ctx
= f
.file
->private_data
;
9666 mutex_lock(&ctx
->uring_lock
);
9667 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
9668 mutex_unlock(&ctx
->uring_lock
);
9669 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
9670 ctx
->cq_ev_fd
!= NULL
, ret
);
9676 static int __init
io_uring_init(void)
9678 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
9679 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
9680 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
9683 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
9684 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
9685 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
9686 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
9687 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
9688 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
9689 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
9690 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
9691 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
9692 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
9693 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
9694 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
9695 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
9696 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
9697 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
9698 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
9699 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
9700 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
9701 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
9702 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
9703 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
9704 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
9705 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
9706 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
9707 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
9708 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
9709 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
9710 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
9711 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
9712 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
9713 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
9715 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
9716 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
9717 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
9720 __initcall(io_uring_init
);