1 // SPDX-License-Identifier: GPL-2.0
3 * Shared application/kernel submission and completion ring pairs, for
4 * supporting fast/efficient IO.
6 * A note on the read/write ordering memory barriers that are matched between
7 * the application and kernel side.
9 * After the application reads the CQ ring tail, it must use an
10 * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
11 * before writing the tail (using smp_load_acquire to read the tail will
12 * do). It also needs a smp_mb() before updating CQ head (ordering the
13 * entry load(s) with the head store), pairing with an implicit barrier
14 * through a control-dependency in io_get_cqring (smp_store_release to
15 * store head will do). Failure to do so could lead to reading invalid
18 * Likewise, the application must use an appropriate smp_wmb() before
19 * writing the SQ tail (ordering SQ entry stores with the tail store),
20 * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
21 * to store the tail will do). And it needs a barrier ordering the SQ
22 * head load before writing new SQ entries (smp_load_acquire to read
25 * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
26 * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
27 * updating the SQ tail; a full memory barrier smp_mb() is needed
30 * Also see the examples in the liburing library:
32 * git://git.kernel.dk/liburing
34 * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
35 * from data shared between the kernel and application. This is done both
36 * for ordering purposes, but also to ensure that once a value is loaded from
37 * data that the application could potentially modify, it remains stable.
39 * Copyright (C) 2018-2019 Jens Axboe
40 * Copyright (c) 2018-2019 Christoph Hellwig
42 #include <linux/kernel.h>
43 #include <linux/init.h>
44 #include <linux/errno.h>
45 #include <linux/syscalls.h>
46 #include <linux/compat.h>
47 #include <net/compat.h>
48 #include <linux/refcount.h>
49 #include <linux/uio.h>
50 #include <linux/bits.h>
52 #include <linux/sched/signal.h>
54 #include <linux/file.h>
55 #include <linux/fdtable.h>
57 #include <linux/mman.h>
58 #include <linux/percpu.h>
59 #include <linux/slab.h>
60 #include <linux/kthread.h>
61 #include <linux/blkdev.h>
62 #include <linux/bvec.h>
63 #include <linux/net.h>
65 #include <net/af_unix.h>
67 #include <linux/anon_inodes.h>
68 #include <linux/sched/mm.h>
69 #include <linux/uaccess.h>
70 #include <linux/nospec.h>
71 #include <linux/sizes.h>
72 #include <linux/hugetlb.h>
73 #include <linux/highmem.h>
74 #include <linux/namei.h>
75 #include <linux/fsnotify.h>
76 #include <linux/fadvise.h>
77 #include <linux/eventpoll.h>
78 #include <linux/fs_struct.h>
79 #include <linux/splice.h>
80 #include <linux/task_work.h>
81 #include <linux/pagemap.h>
82 #include <linux/io_uring.h>
83 #include <linux/blk-cgroup.h>
84 #include <linux/audit.h>
86 #define CREATE_TRACE_POINTS
87 #include <trace/events/io_uring.h>
89 #include <uapi/linux/io_uring.h>
94 #define IORING_MAX_ENTRIES 32768
95 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
98 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
100 #define IORING_FILE_TABLE_SHIFT 9
101 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
102 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
103 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
104 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
105 IORING_REGISTER_LAST + IORING_OP_LAST)
108 u32 head ____cacheline_aligned_in_smp
;
109 u32 tail ____cacheline_aligned_in_smp
;
113 * This data is shared with the application through the mmap at offsets
114 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
116 * The offsets to the member fields are published through struct
117 * io_sqring_offsets when calling io_uring_setup.
121 * Head and tail offsets into the ring; the offsets need to be
122 * masked to get valid indices.
124 * The kernel controls head of the sq ring and the tail of the cq ring,
125 * and the application controls tail of the sq ring and the head of the
128 struct io_uring sq
, cq
;
130 * Bitmasks to apply to head and tail offsets (constant, equals
133 u32 sq_ring_mask
, cq_ring_mask
;
134 /* Ring sizes (constant, power of 2) */
135 u32 sq_ring_entries
, cq_ring_entries
;
137 * Number of invalid entries dropped by the kernel due to
138 * invalid index stored in array
140 * Written by the kernel, shouldn't be modified by the
141 * application (i.e. get number of "new events" by comparing to
144 * After a new SQ head value was read by the application this
145 * counter includes all submissions that were dropped reaching
146 * the new SQ head (and possibly more).
152 * Written by the kernel, shouldn't be modified by the
155 * The application needs a full memory barrier before checking
156 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
162 * Written by the application, shouldn't be modified by the
167 * Number of completion events lost because the queue was full;
168 * this should be avoided by the application by making sure
169 * there are not more requests pending than there is space in
170 * the completion queue.
172 * Written by the kernel, shouldn't be modified by the
173 * application (i.e. get number of "new events" by comparing to
176 * As completion events come in out of order this counter is not
177 * ordered with any other data.
181 * Ring buffer of completion events.
183 * The kernel writes completion events fresh every time they are
184 * produced, so the application is allowed to modify pending
187 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
190 struct io_mapped_ubuf
{
193 struct bio_vec
*bvec
;
194 unsigned int nr_bvecs
;
195 unsigned long acct_pages
;
198 struct fixed_file_table
{
202 struct fixed_file_ref_node
{
203 struct percpu_ref refs
;
204 struct list_head node
;
205 struct list_head file_list
;
206 struct fixed_file_data
*file_data
;
207 struct llist_node llist
;
211 struct fixed_file_data
{
212 struct fixed_file_table
*table
;
213 struct io_ring_ctx
*ctx
;
215 struct fixed_file_ref_node
*node
;
216 struct percpu_ref refs
;
217 struct completion done
;
218 struct list_head ref_list
;
223 struct list_head list
;
229 struct io_restriction
{
230 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
231 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
232 u8 sqe_flags_allowed
;
233 u8 sqe_flags_required
;
241 /* ctx's that are using this sqd */
242 struct list_head ctx_list
;
243 struct list_head ctx_new_list
;
244 struct mutex ctx_lock
;
246 struct task_struct
*thread
;
247 struct wait_queue_head wait
;
249 unsigned sq_thread_idle
;
254 struct percpu_ref refs
;
255 } ____cacheline_aligned_in_smp
;
259 unsigned int compat
: 1;
260 unsigned int limit_mem
: 1;
261 unsigned int cq_overflow_flushed
: 1;
262 unsigned int drain_next
: 1;
263 unsigned int eventfd_async
: 1;
264 unsigned int restricted
: 1;
265 unsigned int sqo_dead
: 1;
268 * Ring buffer of indices into array of io_uring_sqe, which is
269 * mmapped by the application using the IORING_OFF_SQES offset.
271 * This indirection could e.g. be used to assign fixed
272 * io_uring_sqe entries to operations and only submit them to
273 * the queue when needed.
275 * The kernel modifies neither the indices array nor the entries
279 unsigned cached_sq_head
;
282 unsigned sq_thread_idle
;
283 unsigned cached_sq_dropped
;
284 unsigned cached_cq_overflow
;
285 unsigned long sq_check_overflow
;
287 struct list_head defer_list
;
288 struct list_head timeout_list
;
289 struct list_head cq_overflow_list
;
291 struct io_uring_sqe
*sq_sqes
;
292 } ____cacheline_aligned_in_smp
;
294 struct io_rings
*rings
;
300 * For SQPOLL usage - we hold a reference to the parent task, so we
301 * have access to the ->files
303 struct task_struct
*sqo_task
;
305 /* Only used for accounting purposes */
306 struct mm_struct
*mm_account
;
308 #ifdef CONFIG_BLK_CGROUP
309 struct cgroup_subsys_state
*sqo_blkcg_css
;
312 struct io_sq_data
*sq_data
; /* if using sq thread polling */
314 struct wait_queue_head sqo_sq_wait
;
315 struct list_head sqd_list
;
318 * If used, fixed file set. Writers must ensure that ->refs is dead,
319 * readers must ensure that ->refs is alive as long as the file* is
320 * used. Only updated through io_uring_register(2).
322 struct fixed_file_data
*file_data
;
323 unsigned nr_user_files
;
325 /* if used, fixed mapped user buffers */
326 unsigned nr_user_bufs
;
327 struct io_mapped_ubuf
*user_bufs
;
329 struct user_struct
*user
;
331 const struct cred
*creds
;
335 unsigned int sessionid
;
338 struct completion ref_comp
;
339 struct completion sq_thread_comp
;
341 /* if all else fails... */
342 struct io_kiocb
*fallback_req
;
344 #if defined(CONFIG_UNIX)
345 struct socket
*ring_sock
;
348 struct idr io_buffer_idr
;
350 struct idr personality_idr
;
353 unsigned cached_cq_tail
;
356 atomic_t cq_timeouts
;
357 unsigned cq_last_tm_flush
;
358 unsigned long cq_check_overflow
;
359 struct wait_queue_head cq_wait
;
360 struct fasync_struct
*cq_fasync
;
361 struct eventfd_ctx
*cq_ev_fd
;
362 } ____cacheline_aligned_in_smp
;
365 struct mutex uring_lock
;
366 wait_queue_head_t wait
;
367 } ____cacheline_aligned_in_smp
;
370 spinlock_t completion_lock
;
373 * ->iopoll_list is protected by the ctx->uring_lock for
374 * io_uring instances that don't use IORING_SETUP_SQPOLL.
375 * For SQPOLL, only the single threaded io_sq_thread() will
376 * manipulate the list, hence no extra locking is needed there.
378 struct list_head iopoll_list
;
379 struct hlist_head
*cancel_hash
;
380 unsigned cancel_hash_bits
;
381 bool poll_multi_file
;
383 spinlock_t inflight_lock
;
384 struct list_head inflight_list
;
385 } ____cacheline_aligned_in_smp
;
387 struct delayed_work file_put_work
;
388 struct llist_head file_put_llist
;
390 struct work_struct exit_work
;
391 struct io_restriction restrictions
;
395 * First field must be the file pointer in all the
396 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
398 struct io_poll_iocb
{
400 struct wait_queue_head
*head
;
404 struct wait_queue_entry wait
;
407 struct io_poll_remove
{
414 struct file
*put_file
;
418 struct io_timeout_data
{
419 struct io_kiocb
*req
;
420 struct hrtimer timer
;
421 struct timespec64 ts
;
422 enum hrtimer_mode mode
;
427 struct sockaddr __user
*addr
;
428 int __user
*addr_len
;
430 unsigned long nofile
;
450 struct list_head list
;
451 /* head of the link, used by linked timeouts only */
452 struct io_kiocb
*head
;
455 struct io_timeout_rem
{
460 struct timespec64 ts
;
465 /* NOTE: kiocb has the file as the first member, so don't do it here */
473 struct sockaddr __user
*addr
;
480 struct user_msghdr __user
*umsg
;
486 struct io_buffer
*kbuf
;
492 bool ignore_nonblock
;
493 struct filename
*filename
;
495 unsigned long nofile
;
498 struct io_files_update
{
524 struct epoll_event event
;
528 struct file
*file_out
;
529 struct file
*file_in
;
536 struct io_provide_buf
{
550 const char __user
*filename
;
551 struct statx __user
*buffer
;
563 struct filename
*oldpath
;
564 struct filename
*newpath
;
572 struct filename
*filename
;
575 struct io_completion
{
577 struct list_head list
;
581 struct io_async_connect
{
582 struct sockaddr_storage address
;
585 struct io_async_msghdr
{
586 struct iovec fast_iov
[UIO_FASTIOV
];
588 struct sockaddr __user
*uaddr
;
590 struct sockaddr_storage addr
;
594 struct iovec fast_iov
[UIO_FASTIOV
];
595 const struct iovec
*free_iovec
;
596 struct iov_iter iter
;
598 struct wait_page_queue wpq
;
602 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
603 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
604 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
605 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
606 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
607 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
613 REQ_F_LINK_TIMEOUT_BIT
,
615 REQ_F_NEED_CLEANUP_BIT
,
617 REQ_F_BUFFER_SELECTED_BIT
,
618 REQ_F_NO_FILE_TABLE_BIT
,
619 REQ_F_WORK_INITIALIZED_BIT
,
620 REQ_F_LTIMEOUT_ACTIVE_BIT
,
622 /* not a real bit, just to check we're not overflowing the space */
628 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
629 /* drain existing IO first */
630 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
632 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
633 /* doesn't sever on completion < 0 */
634 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
636 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
637 /* IOSQE_BUFFER_SELECT */
638 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
640 /* fail rest of links */
641 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
642 /* on inflight list */
643 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
644 /* read/write uses file position */
645 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
646 /* must not punt to workers */
647 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
648 /* has or had linked timeout */
649 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
651 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
653 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
654 /* already went through poll handler */
655 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
656 /* buffer already selected */
657 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
658 /* doesn't need file table for this request */
659 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
660 /* io_wq_work is initialized */
661 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
662 /* linked timeout is active, i.e. prepared by link's head */
663 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
667 struct io_poll_iocb poll
;
668 struct io_poll_iocb
*double_poll
;
672 * NOTE! Each of the iocb union members has the file pointer
673 * as the first entry in their struct definition. So you can
674 * access the file pointer through any of the sub-structs,
675 * or directly as just 'ki_filp' in this struct.
681 struct io_poll_iocb poll
;
682 struct io_poll_remove poll_remove
;
683 struct io_accept accept
;
685 struct io_cancel cancel
;
686 struct io_timeout timeout
;
687 struct io_timeout_rem timeout_rem
;
688 struct io_connect connect
;
689 struct io_sr_msg sr_msg
;
691 struct io_close close
;
692 struct io_files_update files_update
;
693 struct io_fadvise fadvise
;
694 struct io_madvise madvise
;
695 struct io_epoll epoll
;
696 struct io_splice splice
;
697 struct io_provide_buf pbuf
;
698 struct io_statx statx
;
699 struct io_shutdown shutdown
;
700 struct io_rename rename
;
701 struct io_unlink unlink
;
702 /* use only after cleaning per-op data, see io_clean_op() */
703 struct io_completion
compl;
706 /* opcode allocated if it needs to store data for async defer */
709 /* polled IO has completed */
715 struct io_ring_ctx
*ctx
;
718 struct task_struct
*task
;
721 struct io_kiocb
*link
;
722 struct percpu_ref
*fixed_file_refs
;
725 * 1. used with ctx->iopoll_list with reads/writes
726 * 2. to track reqs with ->files (see io_op_def::file_table)
728 struct list_head inflight_entry
;
729 struct callback_head task_work
;
730 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
731 struct hlist_node hash_node
;
732 struct async_poll
*apoll
;
733 struct io_wq_work work
;
736 struct io_defer_entry
{
737 struct list_head list
;
738 struct io_kiocb
*req
;
742 #define IO_IOPOLL_BATCH 8
744 struct io_comp_state
{
746 struct list_head list
;
747 struct io_ring_ctx
*ctx
;
750 struct io_submit_state
{
751 struct blk_plug plug
;
754 * io_kiocb alloc cache
756 void *reqs
[IO_IOPOLL_BATCH
];
757 unsigned int free_reqs
;
762 * Batch completion logic
764 struct io_comp_state comp
;
767 * File reference cache
771 unsigned int file_refs
;
772 unsigned int ios_left
;
776 /* needs req->file assigned */
777 unsigned needs_file
: 1;
778 /* don't fail if file grab fails */
779 unsigned needs_file_no_error
: 1;
780 /* hash wq insertion if file is a regular file */
781 unsigned hash_reg_file
: 1;
782 /* unbound wq insertion if file is a non-regular file */
783 unsigned unbound_nonreg_file
: 1;
784 /* opcode is not supported by this kernel */
785 unsigned not_supported
: 1;
786 /* set if opcode supports polled "wait" */
788 unsigned pollout
: 1;
789 /* op supports buffer selection */
790 unsigned buffer_select
: 1;
791 /* must always have async data allocated */
792 unsigned needs_async_data
: 1;
793 /* should block plug */
795 /* size of async data needed, if any */
796 unsigned short async_size
;
800 static const struct io_op_def io_op_defs
[] = {
801 [IORING_OP_NOP
] = {},
802 [IORING_OP_READV
] = {
804 .unbound_nonreg_file
= 1,
807 .needs_async_data
= 1,
809 .async_size
= sizeof(struct io_async_rw
),
810 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
812 [IORING_OP_WRITEV
] = {
815 .unbound_nonreg_file
= 1,
817 .needs_async_data
= 1,
819 .async_size
= sizeof(struct io_async_rw
),
820 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
823 [IORING_OP_FSYNC
] = {
825 .work_flags
= IO_WQ_WORK_BLKCG
,
827 [IORING_OP_READ_FIXED
] = {
829 .unbound_nonreg_file
= 1,
832 .async_size
= sizeof(struct io_async_rw
),
833 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
835 [IORING_OP_WRITE_FIXED
] = {
838 .unbound_nonreg_file
= 1,
841 .async_size
= sizeof(struct io_async_rw
),
842 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
|
845 [IORING_OP_POLL_ADD
] = {
847 .unbound_nonreg_file
= 1,
849 [IORING_OP_POLL_REMOVE
] = {},
850 [IORING_OP_SYNC_FILE_RANGE
] = {
852 .work_flags
= IO_WQ_WORK_BLKCG
,
854 [IORING_OP_SENDMSG
] = {
856 .unbound_nonreg_file
= 1,
858 .needs_async_data
= 1,
859 .async_size
= sizeof(struct io_async_msghdr
),
860 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
863 [IORING_OP_RECVMSG
] = {
865 .unbound_nonreg_file
= 1,
868 .needs_async_data
= 1,
869 .async_size
= sizeof(struct io_async_msghdr
),
870 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
873 [IORING_OP_TIMEOUT
] = {
874 .needs_async_data
= 1,
875 .async_size
= sizeof(struct io_timeout_data
),
876 .work_flags
= IO_WQ_WORK_MM
,
878 [IORING_OP_TIMEOUT_REMOVE
] = {
879 /* used by timeout updates' prep() */
880 .work_flags
= IO_WQ_WORK_MM
,
882 [IORING_OP_ACCEPT
] = {
884 .unbound_nonreg_file
= 1,
886 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
,
888 [IORING_OP_ASYNC_CANCEL
] = {},
889 [IORING_OP_LINK_TIMEOUT
] = {
890 .needs_async_data
= 1,
891 .async_size
= sizeof(struct io_timeout_data
),
892 .work_flags
= IO_WQ_WORK_MM
,
894 [IORING_OP_CONNECT
] = {
896 .unbound_nonreg_file
= 1,
898 .needs_async_data
= 1,
899 .async_size
= sizeof(struct io_async_connect
),
900 .work_flags
= IO_WQ_WORK_MM
,
902 [IORING_OP_FALLOCATE
] = {
904 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
,
906 [IORING_OP_OPENAT
] = {
907 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
|
908 IO_WQ_WORK_FS
| IO_WQ_WORK_MM
,
910 [IORING_OP_CLOSE
] = {
912 .needs_file_no_error
= 1,
913 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
,
915 [IORING_OP_FILES_UPDATE
] = {
916 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
,
918 [IORING_OP_STATX
] = {
919 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
|
920 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
924 .unbound_nonreg_file
= 1,
928 .async_size
= sizeof(struct io_async_rw
),
929 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
931 [IORING_OP_WRITE
] = {
933 .unbound_nonreg_file
= 1,
936 .async_size
= sizeof(struct io_async_rw
),
937 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
940 [IORING_OP_FADVISE
] = {
942 .work_flags
= IO_WQ_WORK_BLKCG
,
944 [IORING_OP_MADVISE
] = {
945 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
949 .unbound_nonreg_file
= 1,
951 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
955 .unbound_nonreg_file
= 1,
958 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
960 [IORING_OP_OPENAT2
] = {
961 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_FS
|
962 IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
964 [IORING_OP_EPOLL_CTL
] = {
965 .unbound_nonreg_file
= 1,
966 .work_flags
= IO_WQ_WORK_FILES
,
968 [IORING_OP_SPLICE
] = {
971 .unbound_nonreg_file
= 1,
972 .work_flags
= IO_WQ_WORK_BLKCG
,
974 [IORING_OP_PROVIDE_BUFFERS
] = {},
975 [IORING_OP_REMOVE_BUFFERS
] = {},
979 .unbound_nonreg_file
= 1,
981 [IORING_OP_SHUTDOWN
] = {
984 [IORING_OP_RENAMEAT
] = {
985 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
|
986 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
988 [IORING_OP_UNLINKAT
] = {
989 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
|
990 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
994 enum io_mem_account
{
999 static void __io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
1000 struct task_struct
*task
);
1002 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
);
1003 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
1004 struct io_ring_ctx
*ctx
);
1006 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
1007 struct io_comp_state
*cs
);
1008 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
1009 static void io_put_req(struct io_kiocb
*req
);
1010 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
1011 static void io_double_put_req(struct io_kiocb
*req
);
1012 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
1013 static void __io_queue_linked_timeout(struct io_kiocb
*req
);
1014 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1015 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
1016 struct io_uring_files_update
*ip
,
1018 static void __io_clean_op(struct io_kiocb
*req
);
1019 static struct file
*io_file_get(struct io_submit_state
*state
,
1020 struct io_kiocb
*req
, int fd
, bool fixed
);
1021 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
);
1022 static void io_file_put_work(struct work_struct
*work
);
1024 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
1025 struct iovec
**iovec
, struct iov_iter
*iter
,
1027 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
1028 const struct iovec
*fast_iov
,
1029 struct iov_iter
*iter
, bool force
);
1030 static void io_req_drop_files(struct io_kiocb
*req
);
1031 static void io_req_task_queue(struct io_kiocb
*req
);
1033 static struct kmem_cache
*req_cachep
;
1035 static const struct file_operations io_uring_fops
;
1037 struct sock
*io_uring_get_socket(struct file
*file
)
1039 #if defined(CONFIG_UNIX)
1040 if (file
->f_op
== &io_uring_fops
) {
1041 struct io_ring_ctx
*ctx
= file
->private_data
;
1043 return ctx
->ring_sock
->sk
;
1048 EXPORT_SYMBOL(io_uring_get_socket
);
1050 #define io_for_each_link(pos, head) \
1051 for (pos = (head); pos; pos = pos->link)
1053 static inline void io_clean_op(struct io_kiocb
*req
)
1055 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
))
1059 static inline void io_set_resource_node(struct io_kiocb
*req
)
1061 struct io_ring_ctx
*ctx
= req
->ctx
;
1063 if (!req
->fixed_file_refs
) {
1064 req
->fixed_file_refs
= &ctx
->file_data
->node
->refs
;
1065 percpu_ref_get(req
->fixed_file_refs
);
1069 static bool io_match_task(struct io_kiocb
*head
,
1070 struct task_struct
*task
,
1071 struct files_struct
*files
)
1073 struct io_kiocb
*req
;
1075 if (task
&& head
->task
!= task
) {
1076 /* in terms of cancelation, always match if req task is dead */
1077 if (head
->task
->flags
& PF_EXITING
)
1084 io_for_each_link(req
, head
) {
1085 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1087 if (req
->file
&& req
->file
->f_op
== &io_uring_fops
)
1089 if ((req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1090 req
->work
.identity
->files
== files
)
1096 static void io_sq_thread_drop_mm_files(void)
1098 struct files_struct
*files
= current
->files
;
1099 struct mm_struct
*mm
= current
->mm
;
1102 kthread_unuse_mm(mm
);
1107 struct nsproxy
*nsproxy
= current
->nsproxy
;
1110 current
->files
= NULL
;
1111 current
->nsproxy
= NULL
;
1112 task_unlock(current
);
1113 put_files_struct(files
);
1114 put_nsproxy(nsproxy
);
1118 static int __io_sq_thread_acquire_files(struct io_ring_ctx
*ctx
)
1120 if (current
->flags
& PF_EXITING
)
1123 if (!current
->files
) {
1124 struct files_struct
*files
;
1125 struct nsproxy
*nsproxy
;
1127 task_lock(ctx
->sqo_task
);
1128 files
= ctx
->sqo_task
->files
;
1130 task_unlock(ctx
->sqo_task
);
1133 atomic_inc(&files
->count
);
1134 get_nsproxy(ctx
->sqo_task
->nsproxy
);
1135 nsproxy
= ctx
->sqo_task
->nsproxy
;
1136 task_unlock(ctx
->sqo_task
);
1139 current
->files
= files
;
1140 current
->nsproxy
= nsproxy
;
1141 task_unlock(current
);
1146 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
1148 struct mm_struct
*mm
;
1150 if (current
->flags
& PF_EXITING
)
1155 /* Should never happen */
1156 if (unlikely(!(ctx
->flags
& IORING_SETUP_SQPOLL
)))
1159 task_lock(ctx
->sqo_task
);
1160 mm
= ctx
->sqo_task
->mm
;
1161 if (unlikely(!mm
|| !mmget_not_zero(mm
)))
1163 task_unlock(ctx
->sqo_task
);
1173 static int io_sq_thread_acquire_mm_files(struct io_ring_ctx
*ctx
,
1174 struct io_kiocb
*req
)
1176 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1179 if (def
->work_flags
& IO_WQ_WORK_MM
) {
1180 ret
= __io_sq_thread_acquire_mm(ctx
);
1185 if (def
->needs_file
|| (def
->work_flags
& IO_WQ_WORK_FILES
)) {
1186 ret
= __io_sq_thread_acquire_files(ctx
);
1194 static void io_sq_thread_associate_blkcg(struct io_ring_ctx
*ctx
,
1195 struct cgroup_subsys_state
**cur_css
)
1198 #ifdef CONFIG_BLK_CGROUP
1199 /* puts the old one when swapping */
1200 if (*cur_css
!= ctx
->sqo_blkcg_css
) {
1201 kthread_associate_blkcg(ctx
->sqo_blkcg_css
);
1202 *cur_css
= ctx
->sqo_blkcg_css
;
1207 static void io_sq_thread_unassociate_blkcg(void)
1209 #ifdef CONFIG_BLK_CGROUP
1210 kthread_associate_blkcg(NULL
);
1214 static inline void req_set_fail_links(struct io_kiocb
*req
)
1216 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1217 req
->flags
|= REQ_F_FAIL_LINK
;
1221 * None of these are dereferenced, they are simply used to check if any of
1222 * them have changed. If we're under current and check they are still the
1223 * same, we're fine to grab references to them for actual out-of-line use.
1225 static void io_init_identity(struct io_identity
*id
)
1227 id
->files
= current
->files
;
1228 id
->mm
= current
->mm
;
1229 #ifdef CONFIG_BLK_CGROUP
1231 id
->blkcg_css
= blkcg_css();
1234 id
->creds
= current_cred();
1235 id
->nsproxy
= current
->nsproxy
;
1236 id
->fs
= current
->fs
;
1237 id
->fsize
= rlimit(RLIMIT_FSIZE
);
1239 id
->loginuid
= current
->loginuid
;
1240 id
->sessionid
= current
->sessionid
;
1242 refcount_set(&id
->count
, 1);
1245 static inline void __io_req_init_async(struct io_kiocb
*req
)
1247 memset(&req
->work
, 0, sizeof(req
->work
));
1248 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1252 * Note: must call io_req_init_async() for the first time you
1253 * touch any members of io_wq_work.
1255 static inline void io_req_init_async(struct io_kiocb
*req
)
1257 struct io_uring_task
*tctx
= current
->io_uring
;
1259 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1262 __io_req_init_async(req
);
1264 /* Grab a ref if this isn't our static identity */
1265 req
->work
.identity
= tctx
->identity
;
1266 if (tctx
->identity
!= &tctx
->__identity
)
1267 refcount_inc(&req
->work
.identity
->count
);
1270 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
1272 return ctx
->flags
& IORING_SETUP_SQPOLL
;
1275 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1277 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1279 complete(&ctx
->ref_comp
);
1282 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1284 return !req
->timeout
.off
;
1287 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1289 struct io_ring_ctx
*ctx
;
1292 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1296 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
1297 if (!ctx
->fallback_req
)
1301 * Use 5 bits less than the max cq entries, that should give us around
1302 * 32 entries per hash list if totally full and uniformly spread.
1304 hash_bits
= ilog2(p
->cq_entries
);
1308 ctx
->cancel_hash_bits
= hash_bits
;
1309 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1311 if (!ctx
->cancel_hash
)
1313 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1315 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1316 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1319 ctx
->flags
= p
->flags
;
1320 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1321 INIT_LIST_HEAD(&ctx
->sqd_list
);
1322 init_waitqueue_head(&ctx
->cq_wait
);
1323 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1324 init_completion(&ctx
->ref_comp
);
1325 init_completion(&ctx
->sq_thread_comp
);
1326 idr_init(&ctx
->io_buffer_idr
);
1327 idr_init(&ctx
->personality_idr
);
1328 mutex_init(&ctx
->uring_lock
);
1329 init_waitqueue_head(&ctx
->wait
);
1330 spin_lock_init(&ctx
->completion_lock
);
1331 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1332 INIT_LIST_HEAD(&ctx
->defer_list
);
1333 INIT_LIST_HEAD(&ctx
->timeout_list
);
1334 spin_lock_init(&ctx
->inflight_lock
);
1335 INIT_LIST_HEAD(&ctx
->inflight_list
);
1336 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
1337 init_llist_head(&ctx
->file_put_llist
);
1340 if (ctx
->fallback_req
)
1341 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
1342 kfree(ctx
->cancel_hash
);
1347 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1349 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1350 struct io_ring_ctx
*ctx
= req
->ctx
;
1352 return seq
!= ctx
->cached_cq_tail
1353 + READ_ONCE(ctx
->cached_cq_overflow
);
1359 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1361 struct io_rings
*rings
= ctx
->rings
;
1363 /* order cqe stores with ring update */
1364 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1367 static void io_put_identity(struct io_uring_task
*tctx
, struct io_kiocb
*req
)
1369 if (req
->work
.identity
== &tctx
->__identity
)
1371 if (refcount_dec_and_test(&req
->work
.identity
->count
))
1372 kfree(req
->work
.identity
);
1375 static void io_req_clean_work(struct io_kiocb
*req
)
1377 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1380 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1382 if (req
->work
.flags
& IO_WQ_WORK_MM
) {
1383 mmdrop(req
->work
.identity
->mm
);
1384 req
->work
.flags
&= ~IO_WQ_WORK_MM
;
1386 #ifdef CONFIG_BLK_CGROUP
1387 if (req
->work
.flags
& IO_WQ_WORK_BLKCG
) {
1388 css_put(req
->work
.identity
->blkcg_css
);
1389 req
->work
.flags
&= ~IO_WQ_WORK_BLKCG
;
1392 if (req
->work
.flags
& IO_WQ_WORK_CREDS
) {
1393 put_cred(req
->work
.identity
->creds
);
1394 req
->work
.flags
&= ~IO_WQ_WORK_CREDS
;
1396 if (req
->work
.flags
& IO_WQ_WORK_FS
) {
1397 struct fs_struct
*fs
= req
->work
.identity
->fs
;
1399 spin_lock(&req
->work
.identity
->fs
->lock
);
1402 spin_unlock(&req
->work
.identity
->fs
->lock
);
1405 req
->work
.flags
&= ~IO_WQ_WORK_FS
;
1407 if (req
->flags
& REQ_F_INFLIGHT
)
1408 io_req_drop_files(req
);
1410 io_put_identity(req
->task
->io_uring
, req
);
1414 * Create a private copy of io_identity, since some fields don't match
1415 * the current context.
1417 static bool io_identity_cow(struct io_kiocb
*req
)
1419 struct io_uring_task
*tctx
= current
->io_uring
;
1420 const struct cred
*creds
= NULL
;
1421 struct io_identity
*id
;
1423 if (req
->work
.flags
& IO_WQ_WORK_CREDS
)
1424 creds
= req
->work
.identity
->creds
;
1426 id
= kmemdup(req
->work
.identity
, sizeof(*id
), GFP_KERNEL
);
1427 if (unlikely(!id
)) {
1428 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1433 * We can safely just re-init the creds we copied Either the field
1434 * matches the current one, or we haven't grabbed it yet. The only
1435 * exception is ->creds, through registered personalities, so handle
1436 * that one separately.
1438 io_init_identity(id
);
1442 /* add one for this request */
1443 refcount_inc(&id
->count
);
1445 /* drop tctx and req identity references, if needed */
1446 if (tctx
->identity
!= &tctx
->__identity
&&
1447 refcount_dec_and_test(&tctx
->identity
->count
))
1448 kfree(tctx
->identity
);
1449 if (req
->work
.identity
!= &tctx
->__identity
&&
1450 refcount_dec_and_test(&req
->work
.identity
->count
))
1451 kfree(req
->work
.identity
);
1453 req
->work
.identity
= id
;
1454 tctx
->identity
= id
;
1458 static bool io_grab_identity(struct io_kiocb
*req
)
1460 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1461 struct io_identity
*id
= req
->work
.identity
;
1462 struct io_ring_ctx
*ctx
= req
->ctx
;
1464 if (def
->work_flags
& IO_WQ_WORK_FSIZE
) {
1465 if (id
->fsize
!= rlimit(RLIMIT_FSIZE
))
1467 req
->work
.flags
|= IO_WQ_WORK_FSIZE
;
1469 #ifdef CONFIG_BLK_CGROUP
1470 if (!(req
->work
.flags
& IO_WQ_WORK_BLKCG
) &&
1471 (def
->work_flags
& IO_WQ_WORK_BLKCG
)) {
1473 if (id
->blkcg_css
!= blkcg_css()) {
1478 * This should be rare, either the cgroup is dying or the task
1479 * is moving cgroups. Just punt to root for the handful of ios.
1481 if (css_tryget_online(id
->blkcg_css
))
1482 req
->work
.flags
|= IO_WQ_WORK_BLKCG
;
1486 if (!(req
->work
.flags
& IO_WQ_WORK_CREDS
)) {
1487 if (id
->creds
!= current_cred())
1489 get_cred(id
->creds
);
1490 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
1493 if (!uid_eq(current
->loginuid
, id
->loginuid
) ||
1494 current
->sessionid
!= id
->sessionid
)
1497 if (!(req
->work
.flags
& IO_WQ_WORK_FS
) &&
1498 (def
->work_flags
& IO_WQ_WORK_FS
)) {
1499 if (current
->fs
!= id
->fs
)
1501 spin_lock(&id
->fs
->lock
);
1502 if (!id
->fs
->in_exec
) {
1504 req
->work
.flags
|= IO_WQ_WORK_FS
;
1506 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1508 spin_unlock(¤t
->fs
->lock
);
1510 if (!(req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1511 (def
->work_flags
& IO_WQ_WORK_FILES
) &&
1512 !(req
->flags
& REQ_F_NO_FILE_TABLE
)) {
1513 if (id
->files
!= current
->files
||
1514 id
->nsproxy
!= current
->nsproxy
)
1516 atomic_inc(&id
->files
->count
);
1517 get_nsproxy(id
->nsproxy
);
1519 if (!(req
->flags
& REQ_F_INFLIGHT
)) {
1520 req
->flags
|= REQ_F_INFLIGHT
;
1522 spin_lock_irq(&ctx
->inflight_lock
);
1523 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
1524 spin_unlock_irq(&ctx
->inflight_lock
);
1526 req
->work
.flags
|= IO_WQ_WORK_FILES
;
1528 if (!(req
->work
.flags
& IO_WQ_WORK_MM
) &&
1529 (def
->work_flags
& IO_WQ_WORK_MM
)) {
1530 if (id
->mm
!= current
->mm
)
1533 req
->work
.flags
|= IO_WQ_WORK_MM
;
1539 static void io_prep_async_work(struct io_kiocb
*req
)
1541 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1542 struct io_ring_ctx
*ctx
= req
->ctx
;
1544 io_req_init_async(req
);
1546 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1547 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1549 if (req
->flags
& REQ_F_ISREG
) {
1550 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1551 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1553 if (def
->unbound_nonreg_file
)
1554 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1557 /* if we fail grabbing identity, we must COW, regrab, and retry */
1558 if (io_grab_identity(req
))
1561 if (!io_identity_cow(req
))
1564 /* can't fail at this point */
1565 if (!io_grab_identity(req
))
1569 static void io_prep_async_link(struct io_kiocb
*req
)
1571 struct io_kiocb
*cur
;
1573 io_for_each_link(cur
, req
)
1574 io_prep_async_work(cur
);
1577 static struct io_kiocb
*__io_queue_async_work(struct io_kiocb
*req
)
1579 struct io_ring_ctx
*ctx
= req
->ctx
;
1580 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1582 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1583 &req
->work
, req
->flags
);
1584 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1588 static void io_queue_async_work(struct io_kiocb
*req
)
1590 struct io_kiocb
*link
;
1592 /* init ->work of the whole link before punting */
1593 io_prep_async_link(req
);
1594 link
= __io_queue_async_work(req
);
1597 io_queue_linked_timeout(link
);
1600 static void io_kill_timeout(struct io_kiocb
*req
)
1602 struct io_timeout_data
*io
= req
->async_data
;
1605 ret
= hrtimer_try_to_cancel(&io
->timer
);
1607 atomic_set(&req
->ctx
->cq_timeouts
,
1608 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1609 list_del_init(&req
->timeout
.list
);
1610 io_cqring_fill_event(req
, 0);
1611 io_put_req_deferred(req
, 1);
1616 * Returns true if we found and killed one or more timeouts
1618 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
1619 struct files_struct
*files
)
1621 struct io_kiocb
*req
, *tmp
;
1624 spin_lock_irq(&ctx
->completion_lock
);
1625 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
1626 if (io_match_task(req
, tsk
, files
)) {
1627 io_kill_timeout(req
);
1631 spin_unlock_irq(&ctx
->completion_lock
);
1632 return canceled
!= 0;
1635 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1638 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1639 struct io_defer_entry
, list
);
1641 if (req_need_defer(de
->req
, de
->seq
))
1643 list_del_init(&de
->list
);
1644 io_req_task_queue(de
->req
);
1646 } while (!list_empty(&ctx
->defer_list
));
1649 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1653 if (list_empty(&ctx
->timeout_list
))
1656 seq
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
1659 u32 events_needed
, events_got
;
1660 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1661 struct io_kiocb
, timeout
.list
);
1663 if (io_is_timeout_noseq(req
))
1667 * Since seq can easily wrap around over time, subtract
1668 * the last seq at which timeouts were flushed before comparing.
1669 * Assuming not more than 2^31-1 events have happened since,
1670 * these subtractions won't have wrapped, so we can check if
1671 * target is in [last_seq, current_seq] by comparing the two.
1673 events_needed
= req
->timeout
.target_seq
- ctx
->cq_last_tm_flush
;
1674 events_got
= seq
- ctx
->cq_last_tm_flush
;
1675 if (events_got
< events_needed
)
1678 list_del_init(&req
->timeout
.list
);
1679 io_kill_timeout(req
);
1680 } while (!list_empty(&ctx
->timeout_list
));
1682 ctx
->cq_last_tm_flush
= seq
;
1685 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1687 io_flush_timeouts(ctx
);
1688 __io_commit_cqring(ctx
);
1690 if (unlikely(!list_empty(&ctx
->defer_list
)))
1691 __io_queue_deferred(ctx
);
1694 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1696 struct io_rings
*r
= ctx
->rings
;
1698 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1701 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1703 struct io_rings
*rings
= ctx
->rings
;
1706 tail
= ctx
->cached_cq_tail
;
1708 * writes to the cq entry need to come after reading head; the
1709 * control dependency is enough as we're using WRITE_ONCE to
1712 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1715 ctx
->cached_cq_tail
++;
1716 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1719 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1723 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1725 if (!ctx
->eventfd_async
)
1727 return io_wq_current_is_worker();
1730 static inline unsigned __io_cqring_events(struct io_ring_ctx
*ctx
)
1732 return ctx
->cached_cq_tail
- READ_ONCE(ctx
->rings
->cq
.head
);
1735 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1737 /* see waitqueue_active() comment */
1740 if (waitqueue_active(&ctx
->wait
))
1741 wake_up(&ctx
->wait
);
1742 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1743 wake_up(&ctx
->sq_data
->wait
);
1744 if (io_should_trigger_evfd(ctx
))
1745 eventfd_signal(ctx
->cq_ev_fd
, 1);
1746 if (waitqueue_active(&ctx
->cq_wait
)) {
1747 wake_up_interruptible(&ctx
->cq_wait
);
1748 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1752 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx
*ctx
)
1754 /* see waitqueue_active() comment */
1757 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1758 if (waitqueue_active(&ctx
->wait
))
1759 wake_up(&ctx
->wait
);
1761 if (io_should_trigger_evfd(ctx
))
1762 eventfd_signal(ctx
->cq_ev_fd
, 1);
1763 if (waitqueue_active(&ctx
->cq_wait
)) {
1764 wake_up_interruptible(&ctx
->cq_wait
);
1765 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1769 /* Returns true if there are no backlogged entries after the flush */
1770 static bool __io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1771 struct task_struct
*tsk
,
1772 struct files_struct
*files
)
1774 struct io_rings
*rings
= ctx
->rings
;
1775 struct io_kiocb
*req
, *tmp
;
1776 struct io_uring_cqe
*cqe
;
1777 unsigned long flags
;
1778 bool all_flushed
, posted
;
1781 if (!force
&& __io_cqring_events(ctx
) == rings
->cq_ring_entries
)
1785 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1786 list_for_each_entry_safe(req
, tmp
, &ctx
->cq_overflow_list
, compl.list
) {
1787 if (!io_match_task(req
, tsk
, files
))
1790 cqe
= io_get_cqring(ctx
);
1794 list_move(&req
->compl.list
, &list
);
1796 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1797 WRITE_ONCE(cqe
->res
, req
->result
);
1798 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1800 ctx
->cached_cq_overflow
++;
1801 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1802 ctx
->cached_cq_overflow
);
1807 all_flushed
= list_empty(&ctx
->cq_overflow_list
);
1809 clear_bit(0, &ctx
->sq_check_overflow
);
1810 clear_bit(0, &ctx
->cq_check_overflow
);
1811 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1815 io_commit_cqring(ctx
);
1816 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1818 io_cqring_ev_posted(ctx
);
1820 while (!list_empty(&list
)) {
1821 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1822 list_del(&req
->compl.list
);
1829 static void io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1830 struct task_struct
*tsk
,
1831 struct files_struct
*files
)
1833 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1834 /* iopoll syncs against uring_lock, not completion_lock */
1835 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1836 mutex_lock(&ctx
->uring_lock
);
1837 __io_cqring_overflow_flush(ctx
, force
, tsk
, files
);
1838 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1839 mutex_unlock(&ctx
->uring_lock
);
1843 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1845 struct io_ring_ctx
*ctx
= req
->ctx
;
1846 struct io_uring_cqe
*cqe
;
1848 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1851 * If we can't get a cq entry, userspace overflowed the
1852 * submission (by quite a lot). Increment the overflow count in
1855 cqe
= io_get_cqring(ctx
);
1857 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1858 WRITE_ONCE(cqe
->res
, res
);
1859 WRITE_ONCE(cqe
->flags
, cflags
);
1860 } else if (ctx
->cq_overflow_flushed
||
1861 atomic_read(&req
->task
->io_uring
->in_idle
)) {
1863 * If we're in ring overflow flush mode, or in task cancel mode,
1864 * then we cannot store the request for later flushing, we need
1865 * to drop it on the floor.
1867 ctx
->cached_cq_overflow
++;
1868 WRITE_ONCE(ctx
->rings
->cq_overflow
, ctx
->cached_cq_overflow
);
1870 if (list_empty(&ctx
->cq_overflow_list
)) {
1871 set_bit(0, &ctx
->sq_check_overflow
);
1872 set_bit(0, &ctx
->cq_check_overflow
);
1873 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1877 req
->compl.cflags
= cflags
;
1878 refcount_inc(&req
->refs
);
1879 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1883 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1885 __io_cqring_fill_event(req
, res
, 0);
1888 static void io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1890 struct io_ring_ctx
*ctx
= req
->ctx
;
1891 unsigned long flags
;
1893 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1894 __io_cqring_fill_event(req
, res
, cflags
);
1895 io_commit_cqring(ctx
);
1896 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1898 io_cqring_ev_posted(ctx
);
1901 static void io_submit_flush_completions(struct io_comp_state
*cs
)
1903 struct io_ring_ctx
*ctx
= cs
->ctx
;
1905 spin_lock_irq(&ctx
->completion_lock
);
1906 while (!list_empty(&cs
->list
)) {
1907 struct io_kiocb
*req
;
1909 req
= list_first_entry(&cs
->list
, struct io_kiocb
, compl.list
);
1910 list_del(&req
->compl.list
);
1911 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
1914 * io_free_req() doesn't care about completion_lock unless one
1915 * of these flags is set. REQ_F_WORK_INITIALIZED is in the list
1916 * because of a potential deadlock with req->work.fs->lock
1918 if (req
->flags
& (REQ_F_FAIL_LINK
|REQ_F_LINK_TIMEOUT
1919 |REQ_F_WORK_INITIALIZED
)) {
1920 spin_unlock_irq(&ctx
->completion_lock
);
1922 spin_lock_irq(&ctx
->completion_lock
);
1927 io_commit_cqring(ctx
);
1928 spin_unlock_irq(&ctx
->completion_lock
);
1930 io_cqring_ev_posted(ctx
);
1934 static void __io_req_complete(struct io_kiocb
*req
, long res
, unsigned cflags
,
1935 struct io_comp_state
*cs
)
1938 io_cqring_add_event(req
, res
, cflags
);
1943 req
->compl.cflags
= cflags
;
1944 list_add_tail(&req
->compl.list
, &cs
->list
);
1946 io_submit_flush_completions(cs
);
1950 static void io_req_complete(struct io_kiocb
*req
, long res
)
1952 __io_req_complete(req
, res
, 0, NULL
);
1955 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1957 return req
== (struct io_kiocb
*)
1958 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1961 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1963 struct io_kiocb
*req
;
1965 req
= ctx
->fallback_req
;
1966 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1972 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1973 struct io_submit_state
*state
)
1975 if (!state
->free_reqs
) {
1976 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1980 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1981 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1984 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1985 * retry single alloc to be on the safe side.
1987 if (unlikely(ret
<= 0)) {
1988 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1989 if (!state
->reqs
[0])
1993 state
->free_reqs
= ret
;
1997 return state
->reqs
[state
->free_reqs
];
1999 return io_get_fallback_req(ctx
);
2002 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
2009 static void io_dismantle_req(struct io_kiocb
*req
)
2013 if (req
->async_data
)
2014 kfree(req
->async_data
);
2016 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
2017 if (req
->fixed_file_refs
)
2018 percpu_ref_put(req
->fixed_file_refs
);
2019 io_req_clean_work(req
);
2022 static void __io_free_req(struct io_kiocb
*req
)
2024 struct io_uring_task
*tctx
= req
->task
->io_uring
;
2025 struct io_ring_ctx
*ctx
= req
->ctx
;
2027 io_dismantle_req(req
);
2029 percpu_counter_dec(&tctx
->inflight
);
2030 if (atomic_read(&tctx
->in_idle
))
2031 wake_up(&tctx
->wait
);
2032 put_task_struct(req
->task
);
2034 if (likely(!io_is_fallback_req(req
)))
2035 kmem_cache_free(req_cachep
, req
);
2037 clear_bit_unlock(0, (unsigned long *) &ctx
->fallback_req
);
2038 percpu_ref_put(&ctx
->refs
);
2041 static inline void io_remove_next_linked(struct io_kiocb
*req
)
2043 struct io_kiocb
*nxt
= req
->link
;
2045 req
->link
= nxt
->link
;
2049 static void io_kill_linked_timeout(struct io_kiocb
*req
)
2051 struct io_ring_ctx
*ctx
= req
->ctx
;
2052 struct io_kiocb
*link
;
2053 bool cancelled
= false;
2054 unsigned long flags
;
2056 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
2060 * Can happen if a linked timeout fired and link had been like
2061 * req -> link t-out -> link t-out [-> ...]
2063 if (link
&& (link
->flags
& REQ_F_LTIMEOUT_ACTIVE
)) {
2064 struct io_timeout_data
*io
= link
->async_data
;
2067 io_remove_next_linked(req
);
2068 link
->timeout
.head
= NULL
;
2069 ret
= hrtimer_try_to_cancel(&io
->timer
);
2071 io_cqring_fill_event(link
, -ECANCELED
);
2072 io_commit_cqring(ctx
);
2076 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
2077 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
2080 io_cqring_ev_posted(ctx
);
2086 static void io_fail_links(struct io_kiocb
*req
)
2088 struct io_kiocb
*link
, *nxt
;
2089 struct io_ring_ctx
*ctx
= req
->ctx
;
2090 unsigned long flags
;
2092 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
2100 trace_io_uring_fail_link(req
, link
);
2101 io_cqring_fill_event(link
, -ECANCELED
);
2104 * It's ok to free under spinlock as they're not linked anymore,
2105 * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
2108 if (link
->flags
& REQ_F_WORK_INITIALIZED
)
2109 io_put_req_deferred(link
, 2);
2111 io_double_put_req(link
);
2114 io_commit_cqring(ctx
);
2115 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
2117 io_cqring_ev_posted(ctx
);
2120 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
2122 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
2123 io_kill_linked_timeout(req
);
2126 * If LINK is set, we have dependent requests in this chain. If we
2127 * didn't fail this request, queue the first one up, moving any other
2128 * dependencies to the next request. In case of failure, fail the rest
2131 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
))) {
2132 struct io_kiocb
*nxt
= req
->link
;
2141 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
2143 if (likely(!(req
->link
) && !(req
->flags
& REQ_F_LINK_TIMEOUT
)))
2145 return __io_req_find_next(req
);
2148 static int io_req_task_work_add(struct io_kiocb
*req
)
2150 struct task_struct
*tsk
= req
->task
;
2151 struct io_ring_ctx
*ctx
= req
->ctx
;
2152 enum task_work_notify_mode notify
;
2155 if (tsk
->flags
& PF_EXITING
)
2159 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2160 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2161 * processing task_work. There's no reliable way to tell if TWA_RESUME
2165 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
))
2166 notify
= TWA_SIGNAL
;
2168 ret
= task_work_add(tsk
, &req
->task_work
, notify
);
2170 wake_up_process(tsk
);
2175 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
2177 struct io_ring_ctx
*ctx
= req
->ctx
;
2179 spin_lock_irq(&ctx
->completion_lock
);
2180 io_cqring_fill_event(req
, error
);
2181 io_commit_cqring(ctx
);
2182 spin_unlock_irq(&ctx
->completion_lock
);
2184 io_cqring_ev_posted(ctx
);
2185 req_set_fail_links(req
);
2186 io_double_put_req(req
);
2189 static void io_req_task_cancel(struct callback_head
*cb
)
2191 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2192 struct io_ring_ctx
*ctx
= req
->ctx
;
2194 __io_req_task_cancel(req
, -ECANCELED
);
2195 percpu_ref_put(&ctx
->refs
);
2198 static void __io_req_task_submit(struct io_kiocb
*req
)
2200 struct io_ring_ctx
*ctx
= req
->ctx
;
2202 mutex_lock(&ctx
->uring_lock
);
2203 if (!ctx
->sqo_dead
&&
2204 !__io_sq_thread_acquire_mm(ctx
) &&
2205 !__io_sq_thread_acquire_files(ctx
))
2206 __io_queue_sqe(req
, NULL
);
2208 __io_req_task_cancel(req
, -EFAULT
);
2209 mutex_unlock(&ctx
->uring_lock
);
2211 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
2212 io_sq_thread_drop_mm_files();
2215 static void io_req_task_submit(struct callback_head
*cb
)
2217 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2218 struct io_ring_ctx
*ctx
= req
->ctx
;
2220 __io_req_task_submit(req
);
2221 percpu_ref_put(&ctx
->refs
);
2224 static void io_req_task_queue(struct io_kiocb
*req
)
2228 init_task_work(&req
->task_work
, io_req_task_submit
);
2229 percpu_ref_get(&req
->ctx
->refs
);
2231 ret
= io_req_task_work_add(req
);
2232 if (unlikely(ret
)) {
2233 struct task_struct
*tsk
;
2235 init_task_work(&req
->task_work
, io_req_task_cancel
);
2236 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2237 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2238 wake_up_process(tsk
);
2242 static inline void io_queue_next(struct io_kiocb
*req
)
2244 struct io_kiocb
*nxt
= io_req_find_next(req
);
2247 io_req_task_queue(nxt
);
2250 static void io_free_req(struct io_kiocb
*req
)
2257 void *reqs
[IO_IOPOLL_BATCH
];
2260 struct task_struct
*task
;
2264 static inline void io_init_req_batch(struct req_batch
*rb
)
2271 static void __io_req_free_batch_flush(struct io_ring_ctx
*ctx
,
2272 struct req_batch
*rb
)
2274 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
2275 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
2279 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2280 struct req_batch
*rb
)
2283 __io_req_free_batch_flush(ctx
, rb
);
2285 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2287 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2288 if (atomic_read(&tctx
->in_idle
))
2289 wake_up(&tctx
->wait
);
2290 put_task_struct_many(rb
->task
, rb
->task_refs
);
2295 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
)
2297 if (unlikely(io_is_fallback_req(req
))) {
2303 if (req
->task
!= rb
->task
) {
2305 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2307 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2308 if (atomic_read(&tctx
->in_idle
))
2309 wake_up(&tctx
->wait
);
2310 put_task_struct_many(rb
->task
, rb
->task_refs
);
2312 rb
->task
= req
->task
;
2317 io_dismantle_req(req
);
2318 rb
->reqs
[rb
->to_free
++] = req
;
2319 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
2320 __io_req_free_batch_flush(req
->ctx
, rb
);
2324 * Drop reference to request, return next in chain (if there is one) if this
2325 * was the last reference to this request.
2327 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2329 struct io_kiocb
*nxt
= NULL
;
2331 if (refcount_dec_and_test(&req
->refs
)) {
2332 nxt
= io_req_find_next(req
);
2338 static void io_put_req(struct io_kiocb
*req
)
2340 if (refcount_dec_and_test(&req
->refs
))
2344 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2346 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2351 static void io_free_req_deferred(struct io_kiocb
*req
)
2355 init_task_work(&req
->task_work
, io_put_req_deferred_cb
);
2356 ret
= io_req_task_work_add(req
);
2357 if (unlikely(ret
)) {
2358 struct task_struct
*tsk
;
2360 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2361 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2362 wake_up_process(tsk
);
2366 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2368 if (refcount_sub_and_test(refs
, &req
->refs
))
2369 io_free_req_deferred(req
);
2372 static struct io_wq_work
*io_steal_work(struct io_kiocb
*req
)
2374 struct io_kiocb
*nxt
;
2377 * A ref is owned by io-wq in which context we're. So, if that's the
2378 * last one, it's safe to steal next work. False negatives are Ok,
2379 * it just will be re-punted async in io_put_work()
2381 if (refcount_read(&req
->refs
) != 1)
2384 nxt
= io_req_find_next(req
);
2385 return nxt
? &nxt
->work
: NULL
;
2388 static void io_double_put_req(struct io_kiocb
*req
)
2390 /* drop both submit and complete references */
2391 if (refcount_sub_and_test(2, &req
->refs
))
2395 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
)
2397 /* See comment at the top of this file */
2399 return __io_cqring_events(ctx
);
2402 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2404 struct io_rings
*rings
= ctx
->rings
;
2406 /* make sure SQ entry isn't read before tail */
2407 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2410 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2412 unsigned int cflags
;
2414 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2415 cflags
|= IORING_CQE_F_BUFFER
;
2416 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2421 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2423 struct io_buffer
*kbuf
;
2425 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2426 return io_put_kbuf(req
, kbuf
);
2429 static inline bool io_run_task_work(void)
2432 * Not safe to run on exiting task, and the task_work handling will
2433 * not add work to such a task.
2435 if (unlikely(current
->flags
& PF_EXITING
))
2437 if (current
->task_works
) {
2438 __set_current_state(TASK_RUNNING
);
2446 static void io_iopoll_queue(struct list_head
*again
)
2448 struct io_kiocb
*req
;
2451 req
= list_first_entry(again
, struct io_kiocb
, inflight_entry
);
2452 list_del(&req
->inflight_entry
);
2453 __io_complete_rw(req
, -EAGAIN
, 0, NULL
);
2454 } while (!list_empty(again
));
2458 * Find and free completed poll iocbs
2460 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2461 struct list_head
*done
)
2463 struct req_batch rb
;
2464 struct io_kiocb
*req
;
2467 /* order with ->result store in io_complete_rw_iopoll() */
2470 io_init_req_batch(&rb
);
2471 while (!list_empty(done
)) {
2474 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2475 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2477 req
->iopoll_completed
= 0;
2478 list_move_tail(&req
->inflight_entry
, &again
);
2481 list_del(&req
->inflight_entry
);
2483 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2484 cflags
= io_put_rw_kbuf(req
);
2486 __io_cqring_fill_event(req
, req
->result
, cflags
);
2489 if (refcount_dec_and_test(&req
->refs
))
2490 io_req_free_batch(&rb
, req
);
2493 io_commit_cqring(ctx
);
2494 io_cqring_ev_posted_iopoll(ctx
);
2495 io_req_free_batch_finish(ctx
, &rb
);
2497 if (!list_empty(&again
))
2498 io_iopoll_queue(&again
);
2501 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2504 struct io_kiocb
*req
, *tmp
;
2510 * Only spin for completions if we don't have multiple devices hanging
2511 * off our complete list, and we're under the requested amount.
2513 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2516 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2517 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2520 * Move completed and retryable entries to our local lists.
2521 * If we find a request that requires polling, break out
2522 * and complete those lists first, if we have entries there.
2524 if (READ_ONCE(req
->iopoll_completed
)) {
2525 list_move_tail(&req
->inflight_entry
, &done
);
2528 if (!list_empty(&done
))
2531 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2535 /* iopoll may have completed current req */
2536 if (READ_ONCE(req
->iopoll_completed
))
2537 list_move_tail(&req
->inflight_entry
, &done
);
2544 if (!list_empty(&done
))
2545 io_iopoll_complete(ctx
, nr_events
, &done
);
2551 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2552 * non-spinning poll check - we'll still enter the driver poll loop, but only
2553 * as a non-spinning completion check.
2555 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2558 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2561 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2564 if (*nr_events
>= min
)
2572 * We can't just wait for polled events to come to us, we have to actively
2573 * find and complete them.
2575 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2577 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2580 mutex_lock(&ctx
->uring_lock
);
2581 while (!list_empty(&ctx
->iopoll_list
)) {
2582 unsigned int nr_events
= 0;
2584 io_do_iopoll(ctx
, &nr_events
, 0);
2586 /* let it sleep and repeat later if can't complete a request */
2590 * Ensure we allow local-to-the-cpu processing to take place,
2591 * in this case we need to ensure that we reap all events.
2592 * Also let task_work, etc. to progress by releasing the mutex
2594 if (need_resched()) {
2595 mutex_unlock(&ctx
->uring_lock
);
2597 mutex_lock(&ctx
->uring_lock
);
2600 mutex_unlock(&ctx
->uring_lock
);
2603 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2605 unsigned int nr_events
= 0;
2606 int iters
= 0, ret
= 0;
2609 * We disallow the app entering submit/complete with polling, but we
2610 * still need to lock the ring to prevent racing with polled issue
2611 * that got punted to a workqueue.
2613 mutex_lock(&ctx
->uring_lock
);
2616 * Don't enter poll loop if we already have events pending.
2617 * If we do, we can potentially be spinning for commands that
2618 * already triggered a CQE (eg in error).
2620 if (test_bit(0, &ctx
->cq_check_overflow
))
2621 __io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
2622 if (io_cqring_events(ctx
))
2626 * If a submit got punted to a workqueue, we can have the
2627 * application entering polling for a command before it gets
2628 * issued. That app will hold the uring_lock for the duration
2629 * of the poll right here, so we need to take a breather every
2630 * now and then to ensure that the issue has a chance to add
2631 * the poll to the issued list. Otherwise we can spin here
2632 * forever, while the workqueue is stuck trying to acquire the
2635 if (!(++iters
& 7)) {
2636 mutex_unlock(&ctx
->uring_lock
);
2638 mutex_lock(&ctx
->uring_lock
);
2641 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2645 } while (min
&& !nr_events
&& !need_resched());
2647 mutex_unlock(&ctx
->uring_lock
);
2651 static void kiocb_end_write(struct io_kiocb
*req
)
2654 * Tell lockdep we inherited freeze protection from submission
2657 if (req
->flags
& REQ_F_ISREG
) {
2658 struct inode
*inode
= file_inode(req
->file
);
2660 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2662 file_end_write(req
->file
);
2665 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
,
2666 struct io_comp_state
*cs
)
2668 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2671 if (kiocb
->ki_flags
& IOCB_WRITE
)
2672 kiocb_end_write(req
);
2674 if (res
!= req
->result
)
2675 req_set_fail_links(req
);
2676 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2677 cflags
= io_put_rw_kbuf(req
);
2678 __io_req_complete(req
, res
, cflags
, cs
);
2682 static bool io_resubmit_prep(struct io_kiocb
*req
, int error
)
2684 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2685 ssize_t ret
= -ECANCELED
;
2686 struct iov_iter iter
;
2694 switch (req
->opcode
) {
2695 case IORING_OP_READV
:
2696 case IORING_OP_READ_FIXED
:
2697 case IORING_OP_READ
:
2700 case IORING_OP_WRITEV
:
2701 case IORING_OP_WRITE_FIXED
:
2702 case IORING_OP_WRITE
:
2706 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2711 if (!req
->async_data
) {
2712 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2715 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, &iter
, false);
2723 req_set_fail_links(req
);
2728 static bool io_rw_reissue(struct io_kiocb
*req
, long res
)
2731 umode_t mode
= file_inode(req
->file
)->i_mode
;
2734 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2736 if ((res
!= -EAGAIN
&& res
!= -EOPNOTSUPP
) || io_wq_current_is_worker())
2739 lockdep_assert_held(&req
->ctx
->uring_lock
);
2741 ret
= io_sq_thread_acquire_mm_files(req
->ctx
, req
);
2743 if (io_resubmit_prep(req
, ret
)) {
2744 refcount_inc(&req
->refs
);
2745 io_queue_async_work(req
);
2753 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2754 struct io_comp_state
*cs
)
2756 if (!io_rw_reissue(req
, res
))
2757 io_complete_rw_common(&req
->rw
.kiocb
, res
, cs
);
2760 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2762 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2764 __io_complete_rw(req
, res
, res2
, NULL
);
2767 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2769 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2771 if (kiocb
->ki_flags
& IOCB_WRITE
)
2772 kiocb_end_write(req
);
2774 if (res
!= -EAGAIN
&& res
!= req
->result
)
2775 req_set_fail_links(req
);
2777 WRITE_ONCE(req
->result
, res
);
2778 /* order with io_poll_complete() checking ->result */
2780 WRITE_ONCE(req
->iopoll_completed
, 1);
2784 * After the iocb has been issued, it's safe to be found on the poll list.
2785 * Adding the kiocb to the list AFTER submission ensures that we don't
2786 * find it from a io_iopoll_getevents() thread before the issuer is done
2787 * accessing the kiocb cookie.
2789 static void io_iopoll_req_issued(struct io_kiocb
*req
, bool in_async
)
2791 struct io_ring_ctx
*ctx
= req
->ctx
;
2794 * Track whether we have multiple files in our lists. This will impact
2795 * how we do polling eventually, not spinning if we're on potentially
2796 * different devices.
2798 if (list_empty(&ctx
->iopoll_list
)) {
2799 ctx
->poll_multi_file
= false;
2800 } else if (!ctx
->poll_multi_file
) {
2801 struct io_kiocb
*list_req
;
2803 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2805 if (list_req
->file
!= req
->file
)
2806 ctx
->poll_multi_file
= true;
2810 * For fast devices, IO may have already completed. If it has, add
2811 * it to the front so we find it first.
2813 if (READ_ONCE(req
->iopoll_completed
))
2814 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2816 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2819 * If IORING_SETUP_SQPOLL is enabled, sqes are either handled in sq thread
2820 * task context or in io worker task context. If current task context is
2821 * sq thread, we don't need to check whether should wake up sq thread.
2823 if (in_async
&& (ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2824 wq_has_sleeper(&ctx
->sq_data
->wait
))
2825 wake_up(&ctx
->sq_data
->wait
);
2828 static inline void __io_state_file_put(struct io_submit_state
*state
)
2830 fput_many(state
->file
, state
->file_refs
);
2831 state
->file_refs
= 0;
2834 static inline void io_state_file_put(struct io_submit_state
*state
)
2836 if (state
->file_refs
)
2837 __io_state_file_put(state
);
2841 * Get as many references to a file as we have IOs left in this submission,
2842 * assuming most submissions are for one file, or at least that each file
2843 * has more than one submission.
2845 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2850 if (state
->file_refs
) {
2851 if (state
->fd
== fd
) {
2855 __io_state_file_put(state
);
2857 state
->file
= fget_many(fd
, state
->ios_left
);
2858 if (unlikely(!state
->file
))
2862 state
->file_refs
= state
->ios_left
- 1;
2866 static bool io_bdev_nowait(struct block_device
*bdev
)
2868 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2872 * If we tracked the file through the SCM inflight mechanism, we could support
2873 * any file. For now, just ensure that anything potentially problematic is done
2876 static bool io_file_supports_async(struct file
*file
, int rw
)
2878 umode_t mode
= file_inode(file
)->i_mode
;
2880 if (S_ISBLK(mode
)) {
2881 if (IS_ENABLED(CONFIG_BLOCK
) &&
2882 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2886 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2888 if (S_ISREG(mode
)) {
2889 if (IS_ENABLED(CONFIG_BLOCK
) &&
2890 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2891 file
->f_op
!= &io_uring_fops
)
2896 /* any ->read/write should understand O_NONBLOCK */
2897 if (file
->f_flags
& O_NONBLOCK
)
2900 if (!(file
->f_mode
& FMODE_NOWAIT
))
2904 return file
->f_op
->read_iter
!= NULL
;
2906 return file
->f_op
->write_iter
!= NULL
;
2909 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2911 struct io_ring_ctx
*ctx
= req
->ctx
;
2912 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2916 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2917 req
->flags
|= REQ_F_ISREG
;
2919 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2920 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2921 req
->flags
|= REQ_F_CUR_POS
;
2922 kiocb
->ki_pos
= req
->file
->f_pos
;
2924 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2925 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2926 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2930 ioprio
= READ_ONCE(sqe
->ioprio
);
2932 ret
= ioprio_check_cap(ioprio
);
2936 kiocb
->ki_ioprio
= ioprio
;
2938 kiocb
->ki_ioprio
= get_current_ioprio();
2940 /* don't allow async punt if RWF_NOWAIT was requested */
2941 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2942 req
->flags
|= REQ_F_NOWAIT
;
2944 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2945 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2946 !kiocb
->ki_filp
->f_op
->iopoll
)
2949 kiocb
->ki_flags
|= IOCB_HIPRI
;
2950 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2951 req
->iopoll_completed
= 0;
2953 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2955 kiocb
->ki_complete
= io_complete_rw
;
2958 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2959 req
->rw
.len
= READ_ONCE(sqe
->len
);
2960 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2964 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2970 case -ERESTARTNOINTR
:
2971 case -ERESTARTNOHAND
:
2972 case -ERESTART_RESTARTBLOCK
:
2974 * We can't just restart the syscall, since previously
2975 * submitted sqes may already be in progress. Just fail this
2981 kiocb
->ki_complete(kiocb
, ret
, 0);
2985 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2986 struct io_comp_state
*cs
)
2988 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2989 struct io_async_rw
*io
= req
->async_data
;
2991 /* add previously done IO, if any */
2992 if (io
&& io
->bytes_done
> 0) {
2994 ret
= io
->bytes_done
;
2996 ret
+= io
->bytes_done
;
2999 if (req
->flags
& REQ_F_CUR_POS
)
3000 req
->file
->f_pos
= kiocb
->ki_pos
;
3001 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
3002 __io_complete_rw(req
, ret
, 0, cs
);
3004 io_rw_done(kiocb
, ret
);
3007 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
3008 struct iov_iter
*iter
)
3010 struct io_ring_ctx
*ctx
= req
->ctx
;
3011 size_t len
= req
->rw
.len
;
3012 struct io_mapped_ubuf
*imu
;
3013 u16 index
, buf_index
= req
->buf_index
;
3017 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
3019 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
3020 imu
= &ctx
->user_bufs
[index
];
3021 buf_addr
= req
->rw
.addr
;
3024 if (buf_addr
+ len
< buf_addr
)
3026 /* not inside the mapped region */
3027 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
3031 * May not be a start of buffer, set size appropriately
3032 * and advance us to the beginning.
3034 offset
= buf_addr
- imu
->ubuf
;
3035 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
3039 * Don't use iov_iter_advance() here, as it's really slow for
3040 * using the latter parts of a big fixed buffer - it iterates
3041 * over each segment manually. We can cheat a bit here, because
3044 * 1) it's a BVEC iter, we set it up
3045 * 2) all bvecs are PAGE_SIZE in size, except potentially the
3046 * first and last bvec
3048 * So just find our index, and adjust the iterator afterwards.
3049 * If the offset is within the first bvec (or the whole first
3050 * bvec, just use iov_iter_advance(). This makes it easier
3051 * since we can just skip the first segment, which may not
3052 * be PAGE_SIZE aligned.
3054 const struct bio_vec
*bvec
= imu
->bvec
;
3056 if (offset
<= bvec
->bv_len
) {
3057 iov_iter_advance(iter
, offset
);
3059 unsigned long seg_skip
;
3061 /* skip first vec */
3062 offset
-= bvec
->bv_len
;
3063 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
3065 iter
->bvec
= bvec
+ seg_skip
;
3066 iter
->nr_segs
-= seg_skip
;
3067 iter
->count
-= bvec
->bv_len
+ offset
;
3068 iter
->iov_offset
= offset
& ~PAGE_MASK
;
3075 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3078 mutex_unlock(&ctx
->uring_lock
);
3081 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3084 * "Normal" inline submissions always hold the uring_lock, since we
3085 * grab it from the system call. Same is true for the SQPOLL offload.
3086 * The only exception is when we've detached the request and issue it
3087 * from an async worker thread, grab the lock for that case.
3090 mutex_lock(&ctx
->uring_lock
);
3093 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
3094 int bgid
, struct io_buffer
*kbuf
,
3097 struct io_buffer
*head
;
3099 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
3102 io_ring_submit_lock(req
->ctx
, needs_lock
);
3104 lockdep_assert_held(&req
->ctx
->uring_lock
);
3106 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
3108 if (!list_empty(&head
->list
)) {
3109 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
3111 list_del(&kbuf
->list
);
3114 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
3116 if (*len
> kbuf
->len
)
3119 kbuf
= ERR_PTR(-ENOBUFS
);
3122 io_ring_submit_unlock(req
->ctx
, needs_lock
);
3127 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
3130 struct io_buffer
*kbuf
;
3133 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3134 bgid
= req
->buf_index
;
3135 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
3138 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
3139 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3140 return u64_to_user_ptr(kbuf
->addr
);
3143 #ifdef CONFIG_COMPAT
3144 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
3147 struct compat_iovec __user
*uiov
;
3148 compat_ssize_t clen
;
3152 uiov
= u64_to_user_ptr(req
->rw
.addr
);
3153 if (!access_ok(uiov
, sizeof(*uiov
)))
3155 if (__get_user(clen
, &uiov
->iov_len
))
3161 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3163 return PTR_ERR(buf
);
3164 iov
[0].iov_base
= buf
;
3165 iov
[0].iov_len
= (compat_size_t
) len
;
3170 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3173 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
3177 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3180 len
= iov
[0].iov_len
;
3183 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3185 return PTR_ERR(buf
);
3186 iov
[0].iov_base
= buf
;
3187 iov
[0].iov_len
= len
;
3191 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3194 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3195 struct io_buffer
*kbuf
;
3197 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3198 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3199 iov
[0].iov_len
= kbuf
->len
;
3202 if (req
->rw
.len
!= 1)
3205 #ifdef CONFIG_COMPAT
3206 if (req
->ctx
->compat
)
3207 return io_compat_import(req
, iov
, needs_lock
);
3210 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3213 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
3214 struct iovec
**iovec
, struct iov_iter
*iter
,
3217 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3218 size_t sqe_len
= req
->rw
.len
;
3222 opcode
= req
->opcode
;
3223 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3225 return io_import_fixed(req
, rw
, iter
);
3228 /* buffer index only valid with fixed read/write, or buffer select */
3229 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3232 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3233 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3234 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3236 return PTR_ERR(buf
);
3237 req
->rw
.len
= sqe_len
;
3240 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3245 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3246 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3248 ret
= (*iovec
)->iov_len
;
3249 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
3255 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3259 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3261 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3265 * For files that don't have ->read_iter() and ->write_iter(), handle them
3266 * by looping over ->read() or ->write() manually.
3268 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3270 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3271 struct file
*file
= req
->file
;
3275 * Don't support polled IO through this interface, and we can't
3276 * support non-blocking either. For the latter, this just causes
3277 * the kiocb to be handled from an async context.
3279 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3281 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3284 while (iov_iter_count(iter
)) {
3288 if (!iov_iter_is_bvec(iter
)) {
3289 iovec
= iov_iter_iovec(iter
);
3291 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3292 iovec
.iov_len
= req
->rw
.len
;
3296 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3297 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3299 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3300 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3309 if (nr
!= iovec
.iov_len
)
3313 iov_iter_advance(iter
, nr
);
3319 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3320 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3322 struct io_async_rw
*rw
= req
->async_data
;
3324 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3325 rw
->free_iovec
= iovec
;
3327 /* can only be fixed buffers, no need to do anything */
3328 if (iov_iter_is_bvec(iter
))
3331 unsigned iov_off
= 0;
3333 rw
->iter
.iov
= rw
->fast_iov
;
3334 if (iter
->iov
!= fast_iov
) {
3335 iov_off
= iter
->iov
- fast_iov
;
3336 rw
->iter
.iov
+= iov_off
;
3338 if (rw
->fast_iov
!= fast_iov
)
3339 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3340 sizeof(struct iovec
) * iter
->nr_segs
);
3342 req
->flags
|= REQ_F_NEED_CLEANUP
;
3346 static inline int __io_alloc_async_data(struct io_kiocb
*req
)
3348 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3349 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3350 return req
->async_data
== NULL
;
3353 static int io_alloc_async_data(struct io_kiocb
*req
)
3355 if (!io_op_defs
[req
->opcode
].needs_async_data
)
3358 return __io_alloc_async_data(req
);
3361 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3362 const struct iovec
*fast_iov
,
3363 struct iov_iter
*iter
, bool force
)
3365 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_data
)
3367 if (!req
->async_data
) {
3368 if (__io_alloc_async_data(req
))
3371 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3376 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3378 struct io_async_rw
*iorw
= req
->async_data
;
3379 struct iovec
*iov
= iorw
->fast_iov
;
3382 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3383 if (unlikely(ret
< 0))
3386 iorw
->bytes_done
= 0;
3387 iorw
->free_iovec
= iov
;
3389 req
->flags
|= REQ_F_NEED_CLEANUP
;
3393 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3397 ret
= io_prep_rw(req
, sqe
);
3401 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3404 /* either don't need iovec imported or already have it */
3405 if (!req
->async_data
)
3407 return io_rw_prep_async(req
, READ
);
3411 * This is our waitqueue callback handler, registered through lock_page_async()
3412 * when we initially tried to do the IO with the iocb armed our waitqueue.
3413 * This gets called when the page is unlocked, and we generally expect that to
3414 * happen when the page IO is completed and the page is now uptodate. This will
3415 * queue a task_work based retry of the operation, attempting to copy the data
3416 * again. If the latter fails because the page was NOT uptodate, then we will
3417 * do a thread based blocking retry of the operation. That's the unexpected
3420 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3421 int sync
, void *arg
)
3423 struct wait_page_queue
*wpq
;
3424 struct io_kiocb
*req
= wait
->private;
3425 struct wait_page_key
*key
= arg
;
3428 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3430 if (!wake_page_match(wpq
, key
))
3433 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3434 list_del_init(&wait
->entry
);
3436 init_task_work(&req
->task_work
, io_req_task_submit
);
3437 percpu_ref_get(&req
->ctx
->refs
);
3439 /* submit ref gets dropped, acquire a new one */
3440 refcount_inc(&req
->refs
);
3441 ret
= io_req_task_work_add(req
);
3442 if (unlikely(ret
)) {
3443 struct task_struct
*tsk
;
3445 /* queue just for cancelation */
3446 init_task_work(&req
->task_work
, io_req_task_cancel
);
3447 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
3448 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
3449 wake_up_process(tsk
);
3455 * This controls whether a given IO request should be armed for async page
3456 * based retry. If we return false here, the request is handed to the async
3457 * worker threads for retry. If we're doing buffered reads on a regular file,
3458 * we prepare a private wait_page_queue entry and retry the operation. This
3459 * will either succeed because the page is now uptodate and unlocked, or it
3460 * will register a callback when the page is unlocked at IO completion. Through
3461 * that callback, io_uring uses task_work to setup a retry of the operation.
3462 * That retry will attempt the buffered read again. The retry will generally
3463 * succeed, or in rare cases where it fails, we then fall back to using the
3464 * async worker threads for a blocking retry.
3466 static bool io_rw_should_retry(struct io_kiocb
*req
)
3468 struct io_async_rw
*rw
= req
->async_data
;
3469 struct wait_page_queue
*wait
= &rw
->wpq
;
3470 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3472 /* never retry for NOWAIT, we just complete with -EAGAIN */
3473 if (req
->flags
& REQ_F_NOWAIT
)
3476 /* Only for buffered IO */
3477 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3481 * just use poll if we can, and don't attempt if the fs doesn't
3482 * support callback based unlocks
3484 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3487 wait
->wait
.func
= io_async_buf_func
;
3488 wait
->wait
.private = req
;
3489 wait
->wait
.flags
= 0;
3490 INIT_LIST_HEAD(&wait
->wait
.entry
);
3491 kiocb
->ki_flags
|= IOCB_WAITQ
;
3492 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3493 kiocb
->ki_waitq
= wait
;
3497 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3499 if (req
->file
->f_op
->read_iter
)
3500 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3501 else if (req
->file
->f_op
->read
)
3502 return loop_rw_iter(READ
, req
, iter
);
3507 static int io_read(struct io_kiocb
*req
, bool force_nonblock
,
3508 struct io_comp_state
*cs
)
3510 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3511 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3512 struct iov_iter __iter
, *iter
= &__iter
;
3513 struct io_async_rw
*rw
= req
->async_data
;
3514 ssize_t io_size
, ret
, ret2
;
3521 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3525 io_size
= iov_iter_count(iter
);
3526 req
->result
= io_size
;
3529 /* Ensure we clear previously set non-block flag */
3530 if (!force_nonblock
)
3531 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3533 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3536 /* If the file doesn't support async, just async punt */
3537 no_async
= force_nonblock
&& !io_file_supports_async(req
->file
, READ
);
3541 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3545 ret
= io_iter_do_read(req
, iter
);
3549 } else if (ret
== -EIOCBQUEUED
) {
3552 } else if (ret
== -EAGAIN
) {
3553 /* IOPOLL retry should happen for io-wq threads */
3554 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3556 /* no retry on NONBLOCK marked file */
3557 if (req
->file
->f_flags
& O_NONBLOCK
)
3559 /* some cases will consume bytes even on error returns */
3560 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3563 } else if (ret
< 0) {
3564 /* make sure -ERESTARTSYS -> -EINTR is done */
3568 /* read it all, or we did blocking attempt. no retry. */
3569 if (!iov_iter_count(iter
) || !force_nonblock
||
3570 (req
->file
->f_flags
& O_NONBLOCK
) || !(req
->flags
& REQ_F_ISREG
))
3575 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3582 rw
= req
->async_data
;
3583 /* it's copied and will be cleaned with ->io */
3585 /* now use our persistent iterator, if we aren't already */
3588 rw
->bytes_done
+= ret
;
3589 /* if we can retry, do so with the callbacks armed */
3590 if (!io_rw_should_retry(req
)) {
3591 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3596 * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
3597 * get -EIOCBQUEUED, then we'll get a notification when the desired
3598 * page gets unlocked. We can also get a partial read here, and if we
3599 * do, then just retry at the new offset.
3601 ret
= io_iter_do_read(req
, iter
);
3602 if (ret
== -EIOCBQUEUED
) {
3605 } else if (ret
> 0 && ret
< io_size
) {
3606 /* we got some bytes, but not all. retry. */
3610 kiocb_done(kiocb
, ret
, cs
);
3613 /* it's reportedly faster than delegating the null check to kfree() */
3619 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3623 ret
= io_prep_rw(req
, sqe
);
3627 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3630 /* either don't need iovec imported or already have it */
3631 if (!req
->async_data
)
3633 return io_rw_prep_async(req
, WRITE
);
3636 static int io_write(struct io_kiocb
*req
, bool force_nonblock
,
3637 struct io_comp_state
*cs
)
3639 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3640 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3641 struct iov_iter __iter
, *iter
= &__iter
;
3642 struct io_async_rw
*rw
= req
->async_data
;
3643 ssize_t ret
, ret2
, io_size
;
3649 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3653 io_size
= iov_iter_count(iter
);
3654 req
->result
= io_size
;
3656 /* Ensure we clear previously set non-block flag */
3657 if (!force_nonblock
)
3658 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3660 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3662 /* If the file doesn't support async, just async punt */
3663 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3666 /* file path doesn't support NOWAIT for non-direct_IO */
3667 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3668 (req
->flags
& REQ_F_ISREG
))
3671 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3676 * Open-code file_start_write here to grab freeze protection,
3677 * which will be released by another thread in
3678 * io_complete_rw(). Fool lockdep by telling it the lock got
3679 * released so that it doesn't complain about the held lock when
3680 * we return to userspace.
3682 if (req
->flags
& REQ_F_ISREG
) {
3683 sb_start_write(file_inode(req
->file
)->i_sb
);
3684 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3687 kiocb
->ki_flags
|= IOCB_WRITE
;
3689 if (req
->file
->f_op
->write_iter
)
3690 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3691 else if (req
->file
->f_op
->write
)
3692 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3697 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3698 * retry them without IOCB_NOWAIT.
3700 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3702 /* no retry on NONBLOCK marked file */
3703 if (ret2
== -EAGAIN
&& (req
->file
->f_flags
& O_NONBLOCK
))
3705 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3706 /* IOPOLL retry should happen for io-wq threads */
3707 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3710 kiocb_done(kiocb
, ret2
, cs
);
3713 /* some cases will consume bytes even on error returns */
3714 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3715 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3720 /* it's reportedly faster than delegating the null check to kfree() */
3726 static int io_renameat_prep(struct io_kiocb
*req
,
3727 const struct io_uring_sqe
*sqe
)
3729 struct io_rename
*ren
= &req
->rename
;
3730 const char __user
*oldf
, *newf
;
3732 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3735 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3736 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3737 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3738 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3739 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3741 ren
->oldpath
= getname(oldf
);
3742 if (IS_ERR(ren
->oldpath
))
3743 return PTR_ERR(ren
->oldpath
);
3745 ren
->newpath
= getname(newf
);
3746 if (IS_ERR(ren
->newpath
)) {
3747 putname(ren
->oldpath
);
3748 return PTR_ERR(ren
->newpath
);
3751 req
->flags
|= REQ_F_NEED_CLEANUP
;
3755 static int io_renameat(struct io_kiocb
*req
, bool force_nonblock
)
3757 struct io_rename
*ren
= &req
->rename
;
3763 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3764 ren
->newpath
, ren
->flags
);
3766 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3768 req_set_fail_links(req
);
3769 io_req_complete(req
, ret
);
3773 static int io_unlinkat_prep(struct io_kiocb
*req
,
3774 const struct io_uring_sqe
*sqe
)
3776 struct io_unlink
*un
= &req
->unlink
;
3777 const char __user
*fname
;
3779 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3782 un
->dfd
= READ_ONCE(sqe
->fd
);
3784 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3785 if (un
->flags
& ~AT_REMOVEDIR
)
3788 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3789 un
->filename
= getname(fname
);
3790 if (IS_ERR(un
->filename
))
3791 return PTR_ERR(un
->filename
);
3793 req
->flags
|= REQ_F_NEED_CLEANUP
;
3797 static int io_unlinkat(struct io_kiocb
*req
, bool force_nonblock
)
3799 struct io_unlink
*un
= &req
->unlink
;
3805 if (un
->flags
& AT_REMOVEDIR
)
3806 ret
= do_rmdir(un
->dfd
, un
->filename
);
3808 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3810 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3812 req_set_fail_links(req
);
3813 io_req_complete(req
, ret
);
3817 static int io_shutdown_prep(struct io_kiocb
*req
,
3818 const struct io_uring_sqe
*sqe
)
3820 #if defined(CONFIG_NET)
3821 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3823 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3827 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3834 static int io_shutdown(struct io_kiocb
*req
, bool force_nonblock
)
3836 #if defined(CONFIG_NET)
3837 struct socket
*sock
;
3843 sock
= sock_from_file(req
->file
);
3844 if (unlikely(!sock
))
3847 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3849 req_set_fail_links(req
);
3850 io_req_complete(req
, ret
);
3857 static int __io_splice_prep(struct io_kiocb
*req
,
3858 const struct io_uring_sqe
*sqe
)
3860 struct io_splice
* sp
= &req
->splice
;
3861 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3863 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3867 sp
->len
= READ_ONCE(sqe
->len
);
3868 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3870 if (unlikely(sp
->flags
& ~valid_flags
))
3873 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3874 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3877 req
->flags
|= REQ_F_NEED_CLEANUP
;
3879 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3881 * Splice operation will be punted aync, and here need to
3882 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3884 io_req_init_async(req
);
3885 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3891 static int io_tee_prep(struct io_kiocb
*req
,
3892 const struct io_uring_sqe
*sqe
)
3894 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3896 return __io_splice_prep(req
, sqe
);
3899 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
3901 struct io_splice
*sp
= &req
->splice
;
3902 struct file
*in
= sp
->file_in
;
3903 struct file
*out
= sp
->file_out
;
3904 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3910 ret
= do_tee(in
, out
, sp
->len
, flags
);
3912 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3913 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3916 req_set_fail_links(req
);
3917 io_req_complete(req
, ret
);
3921 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3923 struct io_splice
* sp
= &req
->splice
;
3925 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3926 sp
->off_out
= READ_ONCE(sqe
->off
);
3927 return __io_splice_prep(req
, sqe
);
3930 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
3932 struct io_splice
*sp
= &req
->splice
;
3933 struct file
*in
= sp
->file_in
;
3934 struct file
*out
= sp
->file_out
;
3935 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3936 loff_t
*poff_in
, *poff_out
;
3942 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3943 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3946 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3948 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3949 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3952 req_set_fail_links(req
);
3953 io_req_complete(req
, ret
);
3958 * IORING_OP_NOP just posts a completion event, nothing else.
3960 static int io_nop(struct io_kiocb
*req
, struct io_comp_state
*cs
)
3962 struct io_ring_ctx
*ctx
= req
->ctx
;
3964 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3967 __io_req_complete(req
, 0, 0, cs
);
3971 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3973 struct io_ring_ctx
*ctx
= req
->ctx
;
3978 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3980 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3983 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3984 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3987 req
->sync
.off
= READ_ONCE(sqe
->off
);
3988 req
->sync
.len
= READ_ONCE(sqe
->len
);
3992 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
3994 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3997 /* fsync always requires a blocking context */
4001 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
4002 end
> 0 ? end
: LLONG_MAX
,
4003 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
4005 req_set_fail_links(req
);
4006 io_req_complete(req
, ret
);
4010 static int io_fallocate_prep(struct io_kiocb
*req
,
4011 const struct io_uring_sqe
*sqe
)
4013 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
4015 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4018 req
->sync
.off
= READ_ONCE(sqe
->off
);
4019 req
->sync
.len
= READ_ONCE(sqe
->addr
);
4020 req
->sync
.mode
= READ_ONCE(sqe
->len
);
4024 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
4028 /* fallocate always requiring blocking context */
4031 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
4034 req_set_fail_links(req
);
4035 io_req_complete(req
, ret
);
4039 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4041 const char __user
*fname
;
4044 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
4046 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
4049 /* open.how should be already initialised */
4050 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
4051 req
->open
.how
.flags
|= O_LARGEFILE
;
4053 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
4054 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4055 req
->open
.filename
= getname(fname
);
4056 if (IS_ERR(req
->open
.filename
)) {
4057 ret
= PTR_ERR(req
->open
.filename
);
4058 req
->open
.filename
= NULL
;
4061 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
4062 req
->open
.ignore_nonblock
= false;
4063 req
->flags
|= REQ_F_NEED_CLEANUP
;
4067 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4071 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4073 mode
= READ_ONCE(sqe
->len
);
4074 flags
= READ_ONCE(sqe
->open_flags
);
4075 req
->open
.how
= build_open_how(flags
, mode
);
4076 return __io_openat_prep(req
, sqe
);
4079 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4081 struct open_how __user
*how
;
4085 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4087 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4088 len
= READ_ONCE(sqe
->len
);
4089 if (len
< OPEN_HOW_SIZE_VER0
)
4092 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
4097 return __io_openat_prep(req
, sqe
);
4100 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
4102 struct open_flags op
;
4106 if (force_nonblock
&& !req
->open
.ignore_nonblock
)
4109 ret
= build_open_flags(&req
->open
.how
, &op
);
4113 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
4117 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
4120 ret
= PTR_ERR(file
);
4122 * A work-around to ensure that /proc/self works that way
4123 * that it should - if we get -EOPNOTSUPP back, then assume
4124 * that proc_self_get_link() failed us because we're in async
4125 * context. We should be safe to retry this from the task
4126 * itself with force_nonblock == false set, as it should not
4127 * block on lookup. Would be nice to know this upfront and
4128 * avoid the async dance, but doesn't seem feasible.
4130 if (ret
== -EOPNOTSUPP
&& io_wq_current_is_worker()) {
4131 req
->open
.ignore_nonblock
= true;
4132 refcount_inc(&req
->refs
);
4133 io_req_task_queue(req
);
4137 fsnotify_open(file
);
4138 fd_install(ret
, file
);
4141 putname(req
->open
.filename
);
4142 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4144 req_set_fail_links(req
);
4145 io_req_complete(req
, ret
);
4149 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
4151 return io_openat2(req
, force_nonblock
);
4154 static int io_remove_buffers_prep(struct io_kiocb
*req
,
4155 const struct io_uring_sqe
*sqe
)
4157 struct io_provide_buf
*p
= &req
->pbuf
;
4160 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
4163 tmp
= READ_ONCE(sqe
->fd
);
4164 if (!tmp
|| tmp
> USHRT_MAX
)
4167 memset(p
, 0, sizeof(*p
));
4169 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4173 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
4174 int bgid
, unsigned nbufs
)
4178 /* shouldn't happen */
4182 /* the head kbuf is the list itself */
4183 while (!list_empty(&buf
->list
)) {
4184 struct io_buffer
*nxt
;
4186 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
4187 list_del(&nxt
->list
);
4194 idr_remove(&ctx
->io_buffer_idr
, bgid
);
4199 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
,
4200 struct io_comp_state
*cs
)
4202 struct io_provide_buf
*p
= &req
->pbuf
;
4203 struct io_ring_ctx
*ctx
= req
->ctx
;
4204 struct io_buffer
*head
;
4207 io_ring_submit_lock(ctx
, !force_nonblock
);
4209 lockdep_assert_held(&ctx
->uring_lock
);
4212 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
4214 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
4216 req_set_fail_links(req
);
4218 /* need to hold the lock to complete IOPOLL requests */
4219 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
4220 __io_req_complete(req
, ret
, 0, cs
);
4221 io_ring_submit_unlock(ctx
, !force_nonblock
);
4223 io_ring_submit_unlock(ctx
, !force_nonblock
);
4224 __io_req_complete(req
, ret
, 0, cs
);
4229 static int io_provide_buffers_prep(struct io_kiocb
*req
,
4230 const struct io_uring_sqe
*sqe
)
4232 struct io_provide_buf
*p
= &req
->pbuf
;
4235 if (sqe
->ioprio
|| sqe
->rw_flags
)
4238 tmp
= READ_ONCE(sqe
->fd
);
4239 if (!tmp
|| tmp
> USHRT_MAX
)
4242 p
->addr
= READ_ONCE(sqe
->addr
);
4243 p
->len
= READ_ONCE(sqe
->len
);
4245 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
4248 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4249 tmp
= READ_ONCE(sqe
->off
);
4250 if (tmp
> USHRT_MAX
)
4256 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
4258 struct io_buffer
*buf
;
4259 u64 addr
= pbuf
->addr
;
4260 int i
, bid
= pbuf
->bid
;
4262 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
4263 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
4268 buf
->len
= pbuf
->len
;
4273 INIT_LIST_HEAD(&buf
->list
);
4276 list_add_tail(&buf
->list
, &(*head
)->list
);
4280 return i
? i
: -ENOMEM
;
4283 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
,
4284 struct io_comp_state
*cs
)
4286 struct io_provide_buf
*p
= &req
->pbuf
;
4287 struct io_ring_ctx
*ctx
= req
->ctx
;
4288 struct io_buffer
*head
, *list
;
4291 io_ring_submit_lock(ctx
, !force_nonblock
);
4293 lockdep_assert_held(&ctx
->uring_lock
);
4295 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
4297 ret
= io_add_buffers(p
, &head
);
4302 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
4305 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4311 req_set_fail_links(req
);
4313 /* need to hold the lock to complete IOPOLL requests */
4314 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
4315 __io_req_complete(req
, ret
, 0, cs
);
4316 io_ring_submit_unlock(ctx
, !force_nonblock
);
4318 io_ring_submit_unlock(ctx
, !force_nonblock
);
4319 __io_req_complete(req
, ret
, 0, cs
);
4324 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4325 const struct io_uring_sqe
*sqe
)
4327 #if defined(CONFIG_EPOLL)
4328 if (sqe
->ioprio
|| sqe
->buf_index
)
4330 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4333 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4334 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4335 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4337 if (ep_op_has_event(req
->epoll
.op
)) {
4338 struct epoll_event __user
*ev
;
4340 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4341 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4351 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
,
4352 struct io_comp_state
*cs
)
4354 #if defined(CONFIG_EPOLL)
4355 struct io_epoll
*ie
= &req
->epoll
;
4358 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4359 if (force_nonblock
&& ret
== -EAGAIN
)
4363 req_set_fail_links(req
);
4364 __io_req_complete(req
, ret
, 0, cs
);
4371 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4373 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4374 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4376 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4379 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4380 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4381 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4388 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
4390 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4391 struct io_madvise
*ma
= &req
->madvise
;
4397 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4399 req_set_fail_links(req
);
4400 io_req_complete(req
, ret
);
4407 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4409 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4411 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4414 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4415 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4416 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4420 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
4422 struct io_fadvise
*fa
= &req
->fadvise
;
4425 if (force_nonblock
) {
4426 switch (fa
->advice
) {
4427 case POSIX_FADV_NORMAL
:
4428 case POSIX_FADV_RANDOM
:
4429 case POSIX_FADV_SEQUENTIAL
:
4436 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4438 req_set_fail_links(req
);
4439 io_req_complete(req
, ret
);
4443 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4445 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4447 if (sqe
->ioprio
|| sqe
->buf_index
)
4449 if (req
->flags
& REQ_F_FIXED_FILE
)
4452 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4453 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4454 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4455 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4456 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4461 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
4463 struct io_statx
*ctx
= &req
->statx
;
4466 if (force_nonblock
) {
4467 /* only need file table for an actual valid fd */
4468 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
4469 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4473 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4477 req_set_fail_links(req
);
4478 io_req_complete(req
, ret
);
4482 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4485 * If we queue this for async, it must not be cancellable. That would
4486 * leave the 'file' in an undeterminate state, and here need to modify
4487 * io_wq_work.flags, so initialize io_wq_work firstly.
4489 io_req_init_async(req
);
4491 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4493 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4494 sqe
->rw_flags
|| sqe
->buf_index
)
4496 if (req
->flags
& REQ_F_FIXED_FILE
)
4499 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4500 if ((req
->file
&& req
->file
->f_op
== &io_uring_fops
))
4503 req
->close
.put_file
= NULL
;
4507 static int io_close(struct io_kiocb
*req
, bool force_nonblock
,
4508 struct io_comp_state
*cs
)
4510 struct io_close
*close
= &req
->close
;
4513 /* might be already done during nonblock submission */
4514 if (!close
->put_file
) {
4515 ret
= close_fd_get_file(close
->fd
, &close
->put_file
);
4517 return (ret
== -ENOENT
) ? -EBADF
: ret
;
4520 /* if the file has a flush method, be safe and punt to async */
4521 if (close
->put_file
->f_op
->flush
&& force_nonblock
) {
4522 /* not safe to cancel at this point */
4523 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
4524 /* was never set, but play safe */
4525 req
->flags
&= ~REQ_F_NOWAIT
;
4526 /* avoid grabbing files - we don't need the files */
4527 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4531 /* No ->flush() or already async, safely close from here */
4532 ret
= filp_close(close
->put_file
, req
->work
.identity
->files
);
4534 req_set_fail_links(req
);
4535 fput(close
->put_file
);
4536 close
->put_file
= NULL
;
4537 __io_req_complete(req
, ret
, 0, cs
);
4541 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4543 struct io_ring_ctx
*ctx
= req
->ctx
;
4548 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4550 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4553 req
->sync
.off
= READ_ONCE(sqe
->off
);
4554 req
->sync
.len
= READ_ONCE(sqe
->len
);
4555 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4559 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
4563 /* sync_file_range always requires a blocking context */
4567 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4570 req_set_fail_links(req
);
4571 io_req_complete(req
, ret
);
4575 #if defined(CONFIG_NET)
4576 static int io_setup_async_msg(struct io_kiocb
*req
,
4577 struct io_async_msghdr
*kmsg
)
4579 struct io_async_msghdr
*async_msg
= req
->async_data
;
4583 if (io_alloc_async_data(req
)) {
4584 if (kmsg
->iov
!= kmsg
->fast_iov
)
4588 async_msg
= req
->async_data
;
4589 req
->flags
|= REQ_F_NEED_CLEANUP
;
4590 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4594 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4595 struct io_async_msghdr
*iomsg
)
4597 iomsg
->iov
= iomsg
->fast_iov
;
4598 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4599 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4600 req
->sr_msg
.msg_flags
, &iomsg
->iov
);
4603 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4605 struct io_async_msghdr
*async_msg
= req
->async_data
;
4606 struct io_sr_msg
*sr
= &req
->sr_msg
;
4609 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4612 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4613 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4614 sr
->len
= READ_ONCE(sqe
->len
);
4616 #ifdef CONFIG_COMPAT
4617 if (req
->ctx
->compat
)
4618 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4621 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4623 ret
= io_sendmsg_copy_hdr(req
, async_msg
);
4625 req
->flags
|= REQ_F_NEED_CLEANUP
;
4629 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4630 struct io_comp_state
*cs
)
4632 struct io_async_msghdr iomsg
, *kmsg
;
4633 struct socket
*sock
;
4637 sock
= sock_from_file(req
->file
);
4638 if (unlikely(!sock
))
4641 if (req
->async_data
) {
4642 kmsg
= req
->async_data
;
4643 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4644 /* if iov is set, it's allocated already */
4646 kmsg
->iov
= kmsg
->fast_iov
;
4647 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4649 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4655 flags
= req
->sr_msg
.msg_flags
;
4656 if (flags
& MSG_DONTWAIT
)
4657 req
->flags
|= REQ_F_NOWAIT
;
4658 else if (force_nonblock
)
4659 flags
|= MSG_DONTWAIT
;
4661 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4662 if (force_nonblock
&& ret
== -EAGAIN
)
4663 return io_setup_async_msg(req
, kmsg
);
4664 if (ret
== -ERESTARTSYS
)
4667 if (kmsg
->iov
!= kmsg
->fast_iov
)
4669 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4671 req_set_fail_links(req
);
4672 __io_req_complete(req
, ret
, 0, cs
);
4676 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4677 struct io_comp_state
*cs
)
4679 struct io_sr_msg
*sr
= &req
->sr_msg
;
4682 struct socket
*sock
;
4686 sock
= sock_from_file(req
->file
);
4687 if (unlikely(!sock
))
4690 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4694 msg
.msg_name
= NULL
;
4695 msg
.msg_control
= NULL
;
4696 msg
.msg_controllen
= 0;
4697 msg
.msg_namelen
= 0;
4699 flags
= req
->sr_msg
.msg_flags
;
4700 if (flags
& MSG_DONTWAIT
)
4701 req
->flags
|= REQ_F_NOWAIT
;
4702 else if (force_nonblock
)
4703 flags
|= MSG_DONTWAIT
;
4705 msg
.msg_flags
= flags
;
4706 ret
= sock_sendmsg(sock
, &msg
);
4707 if (force_nonblock
&& ret
== -EAGAIN
)
4709 if (ret
== -ERESTARTSYS
)
4713 req_set_fail_links(req
);
4714 __io_req_complete(req
, ret
, 0, cs
);
4718 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4719 struct io_async_msghdr
*iomsg
)
4721 struct io_sr_msg
*sr
= &req
->sr_msg
;
4722 struct iovec __user
*uiov
;
4726 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4727 &iomsg
->uaddr
, &uiov
, &iov_len
);
4731 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4734 if (copy_from_user(iomsg
->iov
, uiov
, sizeof(*uiov
)))
4736 sr
->len
= iomsg
->iov
[0].iov_len
;
4737 iov_iter_init(&iomsg
->msg
.msg_iter
, READ
, iomsg
->iov
, 1,
4741 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4742 &iomsg
->iov
, &iomsg
->msg
.msg_iter
,
4751 #ifdef CONFIG_COMPAT
4752 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4753 struct io_async_msghdr
*iomsg
)
4755 struct compat_msghdr __user
*msg_compat
;
4756 struct io_sr_msg
*sr
= &req
->sr_msg
;
4757 struct compat_iovec __user
*uiov
;
4762 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4763 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4768 uiov
= compat_ptr(ptr
);
4769 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4770 compat_ssize_t clen
;
4774 if (!access_ok(uiov
, sizeof(*uiov
)))
4776 if (__get_user(clen
, &uiov
->iov_len
))
4781 iomsg
->iov
[0].iov_len
= clen
;
4784 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4785 UIO_FASTIOV
, &iomsg
->iov
,
4786 &iomsg
->msg
.msg_iter
, true);
4795 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4796 struct io_async_msghdr
*iomsg
)
4798 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4799 iomsg
->iov
= iomsg
->fast_iov
;
4801 #ifdef CONFIG_COMPAT
4802 if (req
->ctx
->compat
)
4803 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4806 return __io_recvmsg_copy_hdr(req
, iomsg
);
4809 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4812 struct io_sr_msg
*sr
= &req
->sr_msg
;
4813 struct io_buffer
*kbuf
;
4815 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4820 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4824 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4826 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4829 static int io_recvmsg_prep(struct io_kiocb
*req
,
4830 const struct io_uring_sqe
*sqe
)
4832 struct io_async_msghdr
*async_msg
= req
->async_data
;
4833 struct io_sr_msg
*sr
= &req
->sr_msg
;
4836 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4839 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4840 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4841 sr
->len
= READ_ONCE(sqe
->len
);
4842 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4844 #ifdef CONFIG_COMPAT
4845 if (req
->ctx
->compat
)
4846 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4849 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4851 ret
= io_recvmsg_copy_hdr(req
, async_msg
);
4853 req
->flags
|= REQ_F_NEED_CLEANUP
;
4857 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4858 struct io_comp_state
*cs
)
4860 struct io_async_msghdr iomsg
, *kmsg
;
4861 struct socket
*sock
;
4862 struct io_buffer
*kbuf
;
4864 int ret
, cflags
= 0;
4866 sock
= sock_from_file(req
->file
);
4867 if (unlikely(!sock
))
4870 if (req
->async_data
) {
4871 kmsg
= req
->async_data
;
4872 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4873 /* if iov is set, it's allocated already */
4875 kmsg
->iov
= kmsg
->fast_iov
;
4876 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4878 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4884 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4885 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4887 return PTR_ERR(kbuf
);
4888 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4889 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
4890 1, req
->sr_msg
.len
);
4893 flags
= req
->sr_msg
.msg_flags
;
4894 if (flags
& MSG_DONTWAIT
)
4895 req
->flags
|= REQ_F_NOWAIT
;
4896 else if (force_nonblock
)
4897 flags
|= MSG_DONTWAIT
;
4899 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4900 kmsg
->uaddr
, flags
);
4901 if (force_nonblock
&& ret
== -EAGAIN
)
4902 return io_setup_async_msg(req
, kmsg
);
4903 if (ret
== -ERESTARTSYS
)
4906 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4907 cflags
= io_put_recv_kbuf(req
);
4908 if (kmsg
->iov
!= kmsg
->fast_iov
)
4910 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4912 req_set_fail_links(req
);
4913 __io_req_complete(req
, ret
, cflags
, cs
);
4917 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4918 struct io_comp_state
*cs
)
4920 struct io_buffer
*kbuf
;
4921 struct io_sr_msg
*sr
= &req
->sr_msg
;
4923 void __user
*buf
= sr
->buf
;
4924 struct socket
*sock
;
4927 int ret
, cflags
= 0;
4929 sock
= sock_from_file(req
->file
);
4930 if (unlikely(!sock
))
4933 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4934 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4936 return PTR_ERR(kbuf
);
4937 buf
= u64_to_user_ptr(kbuf
->addr
);
4940 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4944 msg
.msg_name
= NULL
;
4945 msg
.msg_control
= NULL
;
4946 msg
.msg_controllen
= 0;
4947 msg
.msg_namelen
= 0;
4948 msg
.msg_iocb
= NULL
;
4951 flags
= req
->sr_msg
.msg_flags
;
4952 if (flags
& MSG_DONTWAIT
)
4953 req
->flags
|= REQ_F_NOWAIT
;
4954 else if (force_nonblock
)
4955 flags
|= MSG_DONTWAIT
;
4957 ret
= sock_recvmsg(sock
, &msg
, flags
);
4958 if (force_nonblock
&& ret
== -EAGAIN
)
4960 if (ret
== -ERESTARTSYS
)
4963 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4964 cflags
= io_put_recv_kbuf(req
);
4966 req_set_fail_links(req
);
4967 __io_req_complete(req
, ret
, cflags
, cs
);
4971 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4973 struct io_accept
*accept
= &req
->accept
;
4975 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4977 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4980 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4981 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4982 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4983 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4987 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4988 struct io_comp_state
*cs
)
4990 struct io_accept
*accept
= &req
->accept
;
4991 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4994 if (req
->file
->f_flags
& O_NONBLOCK
)
4995 req
->flags
|= REQ_F_NOWAIT
;
4997 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4998 accept
->addr_len
, accept
->flags
,
5000 if (ret
== -EAGAIN
&& force_nonblock
)
5003 if (ret
== -ERESTARTSYS
)
5005 req_set_fail_links(req
);
5007 __io_req_complete(req
, ret
, 0, cs
);
5011 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5013 struct io_connect
*conn
= &req
->connect
;
5014 struct io_async_connect
*io
= req
->async_data
;
5016 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5018 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
5021 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
5022 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
5027 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
5031 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
5032 struct io_comp_state
*cs
)
5034 struct io_async_connect __io
, *io
;
5035 unsigned file_flags
;
5038 if (req
->async_data
) {
5039 io
= req
->async_data
;
5041 ret
= move_addr_to_kernel(req
->connect
.addr
,
5042 req
->connect
.addr_len
,
5049 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
5051 ret
= __sys_connect_file(req
->file
, &io
->address
,
5052 req
->connect
.addr_len
, file_flags
);
5053 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
5054 if (req
->async_data
)
5056 if (io_alloc_async_data(req
)) {
5060 io
= req
->async_data
;
5061 memcpy(req
->async_data
, &__io
, sizeof(__io
));
5064 if (ret
== -ERESTARTSYS
)
5068 req_set_fail_links(req
);
5069 __io_req_complete(req
, ret
, 0, cs
);
5072 #else /* !CONFIG_NET */
5073 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5078 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
5079 struct io_comp_state
*cs
)
5084 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
5085 struct io_comp_state
*cs
)
5090 static int io_recvmsg_prep(struct io_kiocb
*req
,
5091 const struct io_uring_sqe
*sqe
)
5096 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
5097 struct io_comp_state
*cs
)
5102 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
5103 struct io_comp_state
*cs
)
5108 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5113 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
5114 struct io_comp_state
*cs
)
5119 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5124 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
5125 struct io_comp_state
*cs
)
5129 #endif /* CONFIG_NET */
5131 struct io_poll_table
{
5132 struct poll_table_struct pt
;
5133 struct io_kiocb
*req
;
5137 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
5138 __poll_t mask
, task_work_func_t func
)
5142 /* for instances that support it check for an event match first: */
5143 if (mask
&& !(mask
& poll
->events
))
5146 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
5148 list_del_init(&poll
->wait
.entry
);
5151 init_task_work(&req
->task_work
, func
);
5152 percpu_ref_get(&req
->ctx
->refs
);
5155 * If this fails, then the task is exiting. When a task exits, the
5156 * work gets canceled, so just cancel this request as well instead
5157 * of executing it. We can't safely execute it anyway, as we may not
5158 * have the needed state needed for it anyway.
5160 ret
= io_req_task_work_add(req
);
5161 if (unlikely(ret
)) {
5162 struct task_struct
*tsk
;
5164 WRITE_ONCE(poll
->canceled
, true);
5165 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
5166 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
5167 wake_up_process(tsk
);
5172 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
5173 __acquires(&req
->ctx
->completion_lock
)
5175 struct io_ring_ctx
*ctx
= req
->ctx
;
5177 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5178 struct poll_table_struct pt
= { ._key
= poll
->events
};
5180 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
5183 spin_lock_irq(&ctx
->completion_lock
);
5184 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5185 add_wait_queue(poll
->head
, &poll
->wait
);
5192 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
5194 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
5195 if (req
->opcode
== IORING_OP_POLL_ADD
)
5196 return req
->async_data
;
5197 return req
->apoll
->double_poll
;
5200 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
5202 if (req
->opcode
== IORING_OP_POLL_ADD
)
5204 return &req
->apoll
->poll
;
5207 static void io_poll_remove_double(struct io_kiocb
*req
)
5209 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
5211 lockdep_assert_held(&req
->ctx
->completion_lock
);
5213 if (poll
&& poll
->head
) {
5214 struct wait_queue_head
*head
= poll
->head
;
5216 spin_lock(&head
->lock
);
5217 list_del_init(&poll
->wait
.entry
);
5218 if (poll
->wait
.private)
5219 refcount_dec(&req
->refs
);
5221 spin_unlock(&head
->lock
);
5225 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
5227 struct io_ring_ctx
*ctx
= req
->ctx
;
5229 io_poll_remove_double(req
);
5230 req
->poll
.done
= true;
5231 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
5232 io_commit_cqring(ctx
);
5235 static void io_poll_task_func(struct callback_head
*cb
)
5237 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5238 struct io_ring_ctx
*ctx
= req
->ctx
;
5239 struct io_kiocb
*nxt
;
5241 if (io_poll_rewait(req
, &req
->poll
)) {
5242 spin_unlock_irq(&ctx
->completion_lock
);
5244 hash_del(&req
->hash_node
);
5245 io_poll_complete(req
, req
->result
, 0);
5246 spin_unlock_irq(&ctx
->completion_lock
);
5248 nxt
= io_put_req_find_next(req
);
5249 io_cqring_ev_posted(ctx
);
5251 __io_req_task_submit(nxt
);
5254 percpu_ref_put(&ctx
->refs
);
5257 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
5258 int sync
, void *key
)
5260 struct io_kiocb
*req
= wait
->private;
5261 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
5262 __poll_t mask
= key_to_poll(key
);
5264 /* for instances that support it check for an event match first: */
5265 if (mask
&& !(mask
& poll
->events
))
5268 list_del_init(&wait
->entry
);
5270 if (poll
&& poll
->head
) {
5273 spin_lock(&poll
->head
->lock
);
5274 done
= list_empty(&poll
->wait
.entry
);
5276 list_del_init(&poll
->wait
.entry
);
5277 /* make sure double remove sees this as being gone */
5278 wait
->private = NULL
;
5279 spin_unlock(&poll
->head
->lock
);
5281 /* use wait func handler, so it matches the rq type */
5282 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5285 refcount_dec(&req
->refs
);
5289 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
5290 wait_queue_func_t wake_func
)
5294 poll
->canceled
= false;
5295 poll
->events
= events
;
5296 INIT_LIST_HEAD(&poll
->wait
.entry
);
5297 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5300 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5301 struct wait_queue_head
*head
,
5302 struct io_poll_iocb
**poll_ptr
)
5304 struct io_kiocb
*req
= pt
->req
;
5307 * If poll->head is already set, it's because the file being polled
5308 * uses multiple waitqueues for poll handling (eg one for read, one
5309 * for write). Setup a separate io_poll_iocb if this happens.
5311 if (unlikely(poll
->head
)) {
5312 struct io_poll_iocb
*poll_one
= poll
;
5314 /* already have a 2nd entry, fail a third attempt */
5316 pt
->error
= -EINVAL
;
5319 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5321 pt
->error
= -ENOMEM
;
5324 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5325 refcount_inc(&req
->refs
);
5326 poll
->wait
.private = req
;
5333 if (poll
->events
& EPOLLEXCLUSIVE
)
5334 add_wait_queue_exclusive(head
, &poll
->wait
);
5336 add_wait_queue(head
, &poll
->wait
);
5339 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5340 struct poll_table_struct
*p
)
5342 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5343 struct async_poll
*apoll
= pt
->req
->apoll
;
5345 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5348 static void io_async_task_func(struct callback_head
*cb
)
5350 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5351 struct async_poll
*apoll
= req
->apoll
;
5352 struct io_ring_ctx
*ctx
= req
->ctx
;
5354 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5356 if (io_poll_rewait(req
, &apoll
->poll
)) {
5357 spin_unlock_irq(&ctx
->completion_lock
);
5358 percpu_ref_put(&ctx
->refs
);
5362 /* If req is still hashed, it cannot have been canceled. Don't check. */
5363 if (hash_hashed(&req
->hash_node
))
5364 hash_del(&req
->hash_node
);
5366 io_poll_remove_double(req
);
5367 spin_unlock_irq(&ctx
->completion_lock
);
5369 if (!READ_ONCE(apoll
->poll
.canceled
))
5370 __io_req_task_submit(req
);
5372 __io_req_task_cancel(req
, -ECANCELED
);
5374 percpu_ref_put(&ctx
->refs
);
5375 kfree(apoll
->double_poll
);
5379 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5382 struct io_kiocb
*req
= wait
->private;
5383 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5385 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5388 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5391 static void io_poll_req_insert(struct io_kiocb
*req
)
5393 struct io_ring_ctx
*ctx
= req
->ctx
;
5394 struct hlist_head
*list
;
5396 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5397 hlist_add_head(&req
->hash_node
, list
);
5400 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5401 struct io_poll_iocb
*poll
,
5402 struct io_poll_table
*ipt
, __poll_t mask
,
5403 wait_queue_func_t wake_func
)
5404 __acquires(&ctx
->completion_lock
)
5406 struct io_ring_ctx
*ctx
= req
->ctx
;
5407 bool cancel
= false;
5409 INIT_HLIST_NODE(&req
->hash_node
);
5410 io_init_poll_iocb(poll
, mask
, wake_func
);
5411 poll
->file
= req
->file
;
5412 poll
->wait
.private = req
;
5414 ipt
->pt
._key
= mask
;
5416 ipt
->error
= -EINVAL
;
5418 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5420 spin_lock_irq(&ctx
->completion_lock
);
5421 if (likely(poll
->head
)) {
5422 spin_lock(&poll
->head
->lock
);
5423 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5429 if (mask
|| ipt
->error
)
5430 list_del_init(&poll
->wait
.entry
);
5432 WRITE_ONCE(poll
->canceled
, true);
5433 else if (!poll
->done
) /* actually waiting for an event */
5434 io_poll_req_insert(req
);
5435 spin_unlock(&poll
->head
->lock
);
5441 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5443 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5444 struct io_ring_ctx
*ctx
= req
->ctx
;
5445 struct async_poll
*apoll
;
5446 struct io_poll_table ipt
;
5450 if (!req
->file
|| !file_can_poll(req
->file
))
5452 if (req
->flags
& REQ_F_POLLED
)
5456 else if (def
->pollout
)
5460 /* if we can't nonblock try, then no point in arming a poll handler */
5461 if (!io_file_supports_async(req
->file
, rw
))
5464 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5465 if (unlikely(!apoll
))
5467 apoll
->double_poll
= NULL
;
5469 req
->flags
|= REQ_F_POLLED
;
5474 mask
|= POLLIN
| POLLRDNORM
;
5476 mask
|= POLLOUT
| POLLWRNORM
;
5478 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5479 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5480 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5483 mask
|= POLLERR
| POLLPRI
;
5485 ipt
.pt
._qproc
= io_async_queue_proc
;
5487 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5489 if (ret
|| ipt
.error
) {
5490 io_poll_remove_double(req
);
5491 spin_unlock_irq(&ctx
->completion_lock
);
5492 kfree(apoll
->double_poll
);
5496 spin_unlock_irq(&ctx
->completion_lock
);
5497 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5498 apoll
->poll
.events
);
5502 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5503 struct io_poll_iocb
*poll
)
5505 bool do_complete
= false;
5507 spin_lock(&poll
->head
->lock
);
5508 WRITE_ONCE(poll
->canceled
, true);
5509 if (!list_empty(&poll
->wait
.entry
)) {
5510 list_del_init(&poll
->wait
.entry
);
5513 spin_unlock(&poll
->head
->lock
);
5514 hash_del(&req
->hash_node
);
5518 static bool io_poll_remove_one(struct io_kiocb
*req
)
5522 io_poll_remove_double(req
);
5524 if (req
->opcode
== IORING_OP_POLL_ADD
) {
5525 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
5527 struct async_poll
*apoll
= req
->apoll
;
5529 /* non-poll requests have submit ref still */
5530 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
5533 kfree(apoll
->double_poll
);
5539 io_cqring_fill_event(req
, -ECANCELED
);
5540 io_commit_cqring(req
->ctx
);
5541 req_set_fail_links(req
);
5542 io_put_req_deferred(req
, 1);
5549 * Returns true if we found and killed one or more poll requests
5551 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5552 struct files_struct
*files
)
5554 struct hlist_node
*tmp
;
5555 struct io_kiocb
*req
;
5558 spin_lock_irq(&ctx
->completion_lock
);
5559 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5560 struct hlist_head
*list
;
5562 list
= &ctx
->cancel_hash
[i
];
5563 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5564 if (io_match_task(req
, tsk
, files
))
5565 posted
+= io_poll_remove_one(req
);
5568 spin_unlock_irq(&ctx
->completion_lock
);
5571 io_cqring_ev_posted(ctx
);
5576 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5578 struct hlist_head
*list
;
5579 struct io_kiocb
*req
;
5581 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5582 hlist_for_each_entry(req
, list
, hash_node
) {
5583 if (sqe_addr
!= req
->user_data
)
5585 if (io_poll_remove_one(req
))
5593 static int io_poll_remove_prep(struct io_kiocb
*req
,
5594 const struct io_uring_sqe
*sqe
)
5596 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5598 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5602 req
->poll_remove
.addr
= READ_ONCE(sqe
->addr
);
5607 * Find a running poll command that matches one specified in sqe->addr,
5608 * and remove it if found.
5610 static int io_poll_remove(struct io_kiocb
*req
)
5612 struct io_ring_ctx
*ctx
= req
->ctx
;
5615 spin_lock_irq(&ctx
->completion_lock
);
5616 ret
= io_poll_cancel(ctx
, req
->poll_remove
.addr
);
5617 spin_unlock_irq(&ctx
->completion_lock
);
5620 req_set_fail_links(req
);
5621 io_req_complete(req
, ret
);
5625 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5628 struct io_kiocb
*req
= wait
->private;
5629 struct io_poll_iocb
*poll
= &req
->poll
;
5631 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5634 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5635 struct poll_table_struct
*p
)
5637 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5639 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5642 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5644 struct io_poll_iocb
*poll
= &req
->poll
;
5647 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5649 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
5652 events
= READ_ONCE(sqe
->poll32_events
);
5654 events
= swahw32(events
);
5656 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
5657 (events
& EPOLLEXCLUSIVE
);
5661 static int io_poll_add(struct io_kiocb
*req
)
5663 struct io_poll_iocb
*poll
= &req
->poll
;
5664 struct io_ring_ctx
*ctx
= req
->ctx
;
5665 struct io_poll_table ipt
;
5668 ipt
.pt
._qproc
= io_poll_queue_proc
;
5670 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5673 if (mask
) { /* no async, we'd stolen it */
5675 io_poll_complete(req
, mask
, 0);
5677 spin_unlock_irq(&ctx
->completion_lock
);
5680 io_cqring_ev_posted(ctx
);
5686 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5688 struct io_timeout_data
*data
= container_of(timer
,
5689 struct io_timeout_data
, timer
);
5690 struct io_kiocb
*req
= data
->req
;
5691 struct io_ring_ctx
*ctx
= req
->ctx
;
5692 unsigned long flags
;
5694 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5695 list_del_init(&req
->timeout
.list
);
5696 atomic_set(&req
->ctx
->cq_timeouts
,
5697 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5699 io_cqring_fill_event(req
, -ETIME
);
5700 io_commit_cqring(ctx
);
5701 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5703 io_cqring_ev_posted(ctx
);
5704 req_set_fail_links(req
);
5706 return HRTIMER_NORESTART
;
5709 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5712 struct io_timeout_data
*io
;
5713 struct io_kiocb
*req
;
5716 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5717 if (user_data
== req
->user_data
) {
5724 return ERR_PTR(ret
);
5726 io
= req
->async_data
;
5727 ret
= hrtimer_try_to_cancel(&io
->timer
);
5729 return ERR_PTR(-EALREADY
);
5730 list_del_init(&req
->timeout
.list
);
5734 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5736 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5739 return PTR_ERR(req
);
5741 req_set_fail_links(req
);
5742 io_cqring_fill_event(req
, -ECANCELED
);
5743 io_put_req_deferred(req
, 1);
5747 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
5748 struct timespec64
*ts
, enum hrtimer_mode mode
)
5750 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5751 struct io_timeout_data
*data
;
5754 return PTR_ERR(req
);
5756 req
->timeout
.off
= 0; /* noseq */
5757 data
= req
->async_data
;
5758 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
5759 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, mode
);
5760 data
->timer
.function
= io_timeout_fn
;
5761 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
5765 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5766 const struct io_uring_sqe
*sqe
)
5768 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5770 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5772 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5774 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5777 tr
->addr
= READ_ONCE(sqe
->addr
);
5778 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
5779 if (tr
->flags
& IORING_TIMEOUT_UPDATE
) {
5780 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE
|IORING_TIMEOUT_ABS
))
5782 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
5784 } else if (tr
->flags
) {
5785 /* timeout removal doesn't support flags */
5793 * Remove or update an existing timeout command
5795 static int io_timeout_remove(struct io_kiocb
*req
)
5797 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5798 struct io_ring_ctx
*ctx
= req
->ctx
;
5801 spin_lock_irq(&ctx
->completion_lock
);
5802 if (req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
) {
5803 enum hrtimer_mode mode
= (tr
->flags
& IORING_TIMEOUT_ABS
)
5804 ? HRTIMER_MODE_ABS
: HRTIMER_MODE_REL
;
5806 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
, mode
);
5808 ret
= io_timeout_cancel(ctx
, tr
->addr
);
5811 io_cqring_fill_event(req
, ret
);
5812 io_commit_cqring(ctx
);
5813 spin_unlock_irq(&ctx
->completion_lock
);
5814 io_cqring_ev_posted(ctx
);
5816 req_set_fail_links(req
);
5821 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5822 bool is_timeout_link
)
5824 struct io_timeout_data
*data
;
5826 u32 off
= READ_ONCE(sqe
->off
);
5828 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5830 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5832 if (off
&& is_timeout_link
)
5834 flags
= READ_ONCE(sqe
->timeout_flags
);
5835 if (flags
& ~IORING_TIMEOUT_ABS
)
5838 req
->timeout
.off
= off
;
5840 if (!req
->async_data
&& io_alloc_async_data(req
))
5843 data
= req
->async_data
;
5846 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5849 if (flags
& IORING_TIMEOUT_ABS
)
5850 data
->mode
= HRTIMER_MODE_ABS
;
5852 data
->mode
= HRTIMER_MODE_REL
;
5854 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5858 static int io_timeout(struct io_kiocb
*req
)
5860 struct io_ring_ctx
*ctx
= req
->ctx
;
5861 struct io_timeout_data
*data
= req
->async_data
;
5862 struct list_head
*entry
;
5863 u32 tail
, off
= req
->timeout
.off
;
5865 spin_lock_irq(&ctx
->completion_lock
);
5868 * sqe->off holds how many events that need to occur for this
5869 * timeout event to be satisfied. If it isn't set, then this is
5870 * a pure timeout request, sequence isn't used.
5872 if (io_is_timeout_noseq(req
)) {
5873 entry
= ctx
->timeout_list
.prev
;
5877 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5878 req
->timeout
.target_seq
= tail
+ off
;
5880 /* Update the last seq here in case io_flush_timeouts() hasn't.
5881 * This is safe because ->completion_lock is held, and submissions
5882 * and completions are never mixed in the same ->completion_lock section.
5884 ctx
->cq_last_tm_flush
= tail
;
5887 * Insertion sort, ensuring the first entry in the list is always
5888 * the one we need first.
5890 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5891 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5894 if (io_is_timeout_noseq(nxt
))
5896 /* nxt.seq is behind @tail, otherwise would've been completed */
5897 if (off
>= nxt
->timeout
.target_seq
- tail
)
5901 list_add(&req
->timeout
.list
, entry
);
5902 data
->timer
.function
= io_timeout_fn
;
5903 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5904 spin_unlock_irq(&ctx
->completion_lock
);
5908 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5910 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5912 return req
->user_data
== (unsigned long) data
;
5915 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5917 enum io_wq_cancel cancel_ret
;
5920 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5921 switch (cancel_ret
) {
5922 case IO_WQ_CANCEL_OK
:
5925 case IO_WQ_CANCEL_RUNNING
:
5928 case IO_WQ_CANCEL_NOTFOUND
:
5936 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5937 struct io_kiocb
*req
, __u64 sqe_addr
,
5940 unsigned long flags
;
5943 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5944 if (ret
!= -ENOENT
) {
5945 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5949 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5950 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5953 ret
= io_poll_cancel(ctx
, sqe_addr
);
5957 io_cqring_fill_event(req
, ret
);
5958 io_commit_cqring(ctx
);
5959 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5960 io_cqring_ev_posted(ctx
);
5963 req_set_fail_links(req
);
5967 static int io_async_cancel_prep(struct io_kiocb
*req
,
5968 const struct io_uring_sqe
*sqe
)
5970 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5972 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5974 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5977 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5981 static int io_async_cancel(struct io_kiocb
*req
)
5983 struct io_ring_ctx
*ctx
= req
->ctx
;
5985 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
5989 static int io_files_update_prep(struct io_kiocb
*req
,
5990 const struct io_uring_sqe
*sqe
)
5992 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
5994 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5996 if (sqe
->ioprio
|| sqe
->rw_flags
)
5999 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
6000 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
6001 if (!req
->files_update
.nr_args
)
6003 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
6007 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
,
6008 struct io_comp_state
*cs
)
6010 struct io_ring_ctx
*ctx
= req
->ctx
;
6011 struct io_uring_files_update up
;
6017 up
.offset
= req
->files_update
.offset
;
6018 up
.fds
= req
->files_update
.arg
;
6020 mutex_lock(&ctx
->uring_lock
);
6021 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
6022 mutex_unlock(&ctx
->uring_lock
);
6025 req_set_fail_links(req
);
6026 __io_req_complete(req
, ret
, 0, cs
);
6030 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6032 switch (req
->opcode
) {
6035 case IORING_OP_READV
:
6036 case IORING_OP_READ_FIXED
:
6037 case IORING_OP_READ
:
6038 return io_read_prep(req
, sqe
);
6039 case IORING_OP_WRITEV
:
6040 case IORING_OP_WRITE_FIXED
:
6041 case IORING_OP_WRITE
:
6042 return io_write_prep(req
, sqe
);
6043 case IORING_OP_POLL_ADD
:
6044 return io_poll_add_prep(req
, sqe
);
6045 case IORING_OP_POLL_REMOVE
:
6046 return io_poll_remove_prep(req
, sqe
);
6047 case IORING_OP_FSYNC
:
6048 return io_prep_fsync(req
, sqe
);
6049 case IORING_OP_SYNC_FILE_RANGE
:
6050 return io_prep_sfr(req
, sqe
);
6051 case IORING_OP_SENDMSG
:
6052 case IORING_OP_SEND
:
6053 return io_sendmsg_prep(req
, sqe
);
6054 case IORING_OP_RECVMSG
:
6055 case IORING_OP_RECV
:
6056 return io_recvmsg_prep(req
, sqe
);
6057 case IORING_OP_CONNECT
:
6058 return io_connect_prep(req
, sqe
);
6059 case IORING_OP_TIMEOUT
:
6060 return io_timeout_prep(req
, sqe
, false);
6061 case IORING_OP_TIMEOUT_REMOVE
:
6062 return io_timeout_remove_prep(req
, sqe
);
6063 case IORING_OP_ASYNC_CANCEL
:
6064 return io_async_cancel_prep(req
, sqe
);
6065 case IORING_OP_LINK_TIMEOUT
:
6066 return io_timeout_prep(req
, sqe
, true);
6067 case IORING_OP_ACCEPT
:
6068 return io_accept_prep(req
, sqe
);
6069 case IORING_OP_FALLOCATE
:
6070 return io_fallocate_prep(req
, sqe
);
6071 case IORING_OP_OPENAT
:
6072 return io_openat_prep(req
, sqe
);
6073 case IORING_OP_CLOSE
:
6074 return io_close_prep(req
, sqe
);
6075 case IORING_OP_FILES_UPDATE
:
6076 return io_files_update_prep(req
, sqe
);
6077 case IORING_OP_STATX
:
6078 return io_statx_prep(req
, sqe
);
6079 case IORING_OP_FADVISE
:
6080 return io_fadvise_prep(req
, sqe
);
6081 case IORING_OP_MADVISE
:
6082 return io_madvise_prep(req
, sqe
);
6083 case IORING_OP_OPENAT2
:
6084 return io_openat2_prep(req
, sqe
);
6085 case IORING_OP_EPOLL_CTL
:
6086 return io_epoll_ctl_prep(req
, sqe
);
6087 case IORING_OP_SPLICE
:
6088 return io_splice_prep(req
, sqe
);
6089 case IORING_OP_PROVIDE_BUFFERS
:
6090 return io_provide_buffers_prep(req
, sqe
);
6091 case IORING_OP_REMOVE_BUFFERS
:
6092 return io_remove_buffers_prep(req
, sqe
);
6094 return io_tee_prep(req
, sqe
);
6095 case IORING_OP_SHUTDOWN
:
6096 return io_shutdown_prep(req
, sqe
);
6097 case IORING_OP_RENAMEAT
:
6098 return io_renameat_prep(req
, sqe
);
6099 case IORING_OP_UNLINKAT
:
6100 return io_unlinkat_prep(req
, sqe
);
6103 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
6108 static int io_req_defer_prep(struct io_kiocb
*req
,
6109 const struct io_uring_sqe
*sqe
)
6113 if (io_alloc_async_data(req
))
6115 return io_req_prep(req
, sqe
);
6118 static u32
io_get_sequence(struct io_kiocb
*req
)
6120 struct io_kiocb
*pos
;
6121 struct io_ring_ctx
*ctx
= req
->ctx
;
6122 u32 total_submitted
, nr_reqs
= 0;
6124 io_for_each_link(pos
, req
)
6127 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
6128 return total_submitted
- nr_reqs
;
6131 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6133 struct io_ring_ctx
*ctx
= req
->ctx
;
6134 struct io_defer_entry
*de
;
6138 /* Still need defer if there is pending req in defer list. */
6139 if (likely(list_empty_careful(&ctx
->defer_list
) &&
6140 !(req
->flags
& REQ_F_IO_DRAIN
)))
6143 seq
= io_get_sequence(req
);
6144 /* Still a chance to pass the sequence check */
6145 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
6148 if (!req
->async_data
) {
6149 ret
= io_req_defer_prep(req
, sqe
);
6153 io_prep_async_link(req
);
6154 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
6158 spin_lock_irq(&ctx
->completion_lock
);
6159 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
6160 spin_unlock_irq(&ctx
->completion_lock
);
6162 io_queue_async_work(req
);
6163 return -EIOCBQUEUED
;
6166 trace_io_uring_defer(ctx
, req
, req
->user_data
);
6169 list_add_tail(&de
->list
, &ctx
->defer_list
);
6170 spin_unlock_irq(&ctx
->completion_lock
);
6171 return -EIOCBQUEUED
;
6174 static void io_req_drop_files(struct io_kiocb
*req
)
6176 struct io_ring_ctx
*ctx
= req
->ctx
;
6177 struct io_uring_task
*tctx
= req
->task
->io_uring
;
6178 unsigned long flags
;
6180 if (req
->work
.flags
& IO_WQ_WORK_FILES
) {
6181 put_files_struct(req
->work
.identity
->files
);
6182 put_nsproxy(req
->work
.identity
->nsproxy
);
6184 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
6185 list_del(&req
->inflight_entry
);
6186 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
6187 req
->flags
&= ~REQ_F_INFLIGHT
;
6188 req
->work
.flags
&= ~IO_WQ_WORK_FILES
;
6189 if (atomic_read(&tctx
->in_idle
))
6190 wake_up(&tctx
->wait
);
6193 static void __io_clean_op(struct io_kiocb
*req
)
6195 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6196 switch (req
->opcode
) {
6197 case IORING_OP_READV
:
6198 case IORING_OP_READ_FIXED
:
6199 case IORING_OP_READ
:
6200 kfree((void *)(unsigned long)req
->rw
.addr
);
6202 case IORING_OP_RECVMSG
:
6203 case IORING_OP_RECV
:
6204 kfree(req
->sr_msg
.kbuf
);
6207 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
6210 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6211 switch (req
->opcode
) {
6212 case IORING_OP_READV
:
6213 case IORING_OP_READ_FIXED
:
6214 case IORING_OP_READ
:
6215 case IORING_OP_WRITEV
:
6216 case IORING_OP_WRITE_FIXED
:
6217 case IORING_OP_WRITE
: {
6218 struct io_async_rw
*io
= req
->async_data
;
6220 kfree(io
->free_iovec
);
6223 case IORING_OP_RECVMSG
:
6224 case IORING_OP_SENDMSG
: {
6225 struct io_async_msghdr
*io
= req
->async_data
;
6226 if (io
->iov
!= io
->fast_iov
)
6230 case IORING_OP_SPLICE
:
6232 io_put_file(req
, req
->splice
.file_in
,
6233 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
6235 case IORING_OP_OPENAT
:
6236 case IORING_OP_OPENAT2
:
6237 if (req
->open
.filename
)
6238 putname(req
->open
.filename
);
6240 case IORING_OP_RENAMEAT
:
6241 putname(req
->rename
.oldpath
);
6242 putname(req
->rename
.newpath
);
6244 case IORING_OP_UNLINKAT
:
6245 putname(req
->unlink
.filename
);
6248 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
6252 static int io_issue_sqe(struct io_kiocb
*req
, bool force_nonblock
,
6253 struct io_comp_state
*cs
)
6255 struct io_ring_ctx
*ctx
= req
->ctx
;
6258 switch (req
->opcode
) {
6260 ret
= io_nop(req
, cs
);
6262 case IORING_OP_READV
:
6263 case IORING_OP_READ_FIXED
:
6264 case IORING_OP_READ
:
6265 ret
= io_read(req
, force_nonblock
, cs
);
6267 case IORING_OP_WRITEV
:
6268 case IORING_OP_WRITE_FIXED
:
6269 case IORING_OP_WRITE
:
6270 ret
= io_write(req
, force_nonblock
, cs
);
6272 case IORING_OP_FSYNC
:
6273 ret
= io_fsync(req
, force_nonblock
);
6275 case IORING_OP_POLL_ADD
:
6276 ret
= io_poll_add(req
);
6278 case IORING_OP_POLL_REMOVE
:
6279 ret
= io_poll_remove(req
);
6281 case IORING_OP_SYNC_FILE_RANGE
:
6282 ret
= io_sync_file_range(req
, force_nonblock
);
6284 case IORING_OP_SENDMSG
:
6285 ret
= io_sendmsg(req
, force_nonblock
, cs
);
6287 case IORING_OP_SEND
:
6288 ret
= io_send(req
, force_nonblock
, cs
);
6290 case IORING_OP_RECVMSG
:
6291 ret
= io_recvmsg(req
, force_nonblock
, cs
);
6293 case IORING_OP_RECV
:
6294 ret
= io_recv(req
, force_nonblock
, cs
);
6296 case IORING_OP_TIMEOUT
:
6297 ret
= io_timeout(req
);
6299 case IORING_OP_TIMEOUT_REMOVE
:
6300 ret
= io_timeout_remove(req
);
6302 case IORING_OP_ACCEPT
:
6303 ret
= io_accept(req
, force_nonblock
, cs
);
6305 case IORING_OP_CONNECT
:
6306 ret
= io_connect(req
, force_nonblock
, cs
);
6308 case IORING_OP_ASYNC_CANCEL
:
6309 ret
= io_async_cancel(req
);
6311 case IORING_OP_FALLOCATE
:
6312 ret
= io_fallocate(req
, force_nonblock
);
6314 case IORING_OP_OPENAT
:
6315 ret
= io_openat(req
, force_nonblock
);
6317 case IORING_OP_CLOSE
:
6318 ret
= io_close(req
, force_nonblock
, cs
);
6320 case IORING_OP_FILES_UPDATE
:
6321 ret
= io_files_update(req
, force_nonblock
, cs
);
6323 case IORING_OP_STATX
:
6324 ret
= io_statx(req
, force_nonblock
);
6326 case IORING_OP_FADVISE
:
6327 ret
= io_fadvise(req
, force_nonblock
);
6329 case IORING_OP_MADVISE
:
6330 ret
= io_madvise(req
, force_nonblock
);
6332 case IORING_OP_OPENAT2
:
6333 ret
= io_openat2(req
, force_nonblock
);
6335 case IORING_OP_EPOLL_CTL
:
6336 ret
= io_epoll_ctl(req
, force_nonblock
, cs
);
6338 case IORING_OP_SPLICE
:
6339 ret
= io_splice(req
, force_nonblock
);
6341 case IORING_OP_PROVIDE_BUFFERS
:
6342 ret
= io_provide_buffers(req
, force_nonblock
, cs
);
6344 case IORING_OP_REMOVE_BUFFERS
:
6345 ret
= io_remove_buffers(req
, force_nonblock
, cs
);
6348 ret
= io_tee(req
, force_nonblock
);
6350 case IORING_OP_SHUTDOWN
:
6351 ret
= io_shutdown(req
, force_nonblock
);
6353 case IORING_OP_RENAMEAT
:
6354 ret
= io_renameat(req
, force_nonblock
);
6356 case IORING_OP_UNLINKAT
:
6357 ret
= io_unlinkat(req
, force_nonblock
);
6367 /* If the op doesn't have a file, we're not polling for it */
6368 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
6369 const bool in_async
= io_wq_current_is_worker();
6371 /* workqueue context doesn't hold uring_lock, grab it now */
6373 mutex_lock(&ctx
->uring_lock
);
6375 io_iopoll_req_issued(req
, in_async
);
6378 mutex_unlock(&ctx
->uring_lock
);
6384 static struct io_wq_work
*io_wq_submit_work(struct io_wq_work
*work
)
6386 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6387 struct io_kiocb
*timeout
;
6390 timeout
= io_prep_linked_timeout(req
);
6392 io_queue_linked_timeout(timeout
);
6394 /* if NO_CANCEL is set, we must still run the work */
6395 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
6396 IO_WQ_WORK_CANCEL
) {
6402 ret
= io_issue_sqe(req
, false, NULL
);
6404 * We can get EAGAIN for polled IO even though we're
6405 * forcing a sync submission from here, since we can't
6406 * wait for request slots on the block side.
6415 struct io_ring_ctx
*lock_ctx
= NULL
;
6417 if (req
->ctx
->flags
& IORING_SETUP_IOPOLL
)
6418 lock_ctx
= req
->ctx
;
6421 * io_iopoll_complete() does not hold completion_lock to
6422 * complete polled io, so here for polled io, we can not call
6423 * io_req_complete() directly, otherwise there maybe concurrent
6424 * access to cqring, defer_list, etc, which is not safe. Given
6425 * that io_iopoll_complete() is always called under uring_lock,
6426 * so here for polled io, we also get uring_lock to complete
6430 mutex_lock(&lock_ctx
->uring_lock
);
6432 req_set_fail_links(req
);
6433 io_req_complete(req
, ret
);
6436 mutex_unlock(&lock_ctx
->uring_lock
);
6439 return io_steal_work(req
);
6442 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6445 struct fixed_file_table
*table
;
6447 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
6448 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
6451 static struct file
*io_file_get(struct io_submit_state
*state
,
6452 struct io_kiocb
*req
, int fd
, bool fixed
)
6454 struct io_ring_ctx
*ctx
= req
->ctx
;
6458 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6460 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6461 file
= io_file_from_index(ctx
, fd
);
6462 io_set_resource_node(req
);
6464 trace_io_uring_file_get(ctx
, fd
);
6465 file
= __io_file_get(state
, fd
);
6468 if (file
&& file
->f_op
== &io_uring_fops
&&
6469 !(req
->flags
& REQ_F_INFLIGHT
)) {
6470 io_req_init_async(req
);
6471 req
->flags
|= REQ_F_INFLIGHT
;
6473 spin_lock_irq(&ctx
->inflight_lock
);
6474 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
6475 spin_unlock_irq(&ctx
->inflight_lock
);
6481 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6483 struct io_timeout_data
*data
= container_of(timer
,
6484 struct io_timeout_data
, timer
);
6485 struct io_kiocb
*prev
, *req
= data
->req
;
6486 struct io_ring_ctx
*ctx
= req
->ctx
;
6487 unsigned long flags
;
6489 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6490 prev
= req
->timeout
.head
;
6491 req
->timeout
.head
= NULL
;
6494 * We don't expect the list to be empty, that will only happen if we
6495 * race with the completion of the linked work.
6497 if (prev
&& refcount_inc_not_zero(&prev
->refs
))
6498 io_remove_next_linked(prev
);
6501 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6504 req_set_fail_links(prev
);
6505 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6508 io_req_complete(req
, -ETIME
);
6510 return HRTIMER_NORESTART
;
6513 static void __io_queue_linked_timeout(struct io_kiocb
*req
)
6516 * If the back reference is NULL, then our linked request finished
6517 * before we got a chance to setup the timer
6519 if (req
->timeout
.head
) {
6520 struct io_timeout_data
*data
= req
->async_data
;
6522 data
->timer
.function
= io_link_timeout_fn
;
6523 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6528 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6530 struct io_ring_ctx
*ctx
= req
->ctx
;
6532 spin_lock_irq(&ctx
->completion_lock
);
6533 __io_queue_linked_timeout(req
);
6534 spin_unlock_irq(&ctx
->completion_lock
);
6536 /* drop submission reference */
6540 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6542 struct io_kiocb
*nxt
= req
->link
;
6544 if (!nxt
|| (req
->flags
& REQ_F_LINK_TIMEOUT
) ||
6545 nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6548 nxt
->timeout
.head
= req
;
6549 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6550 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6554 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
)
6556 struct io_kiocb
*linked_timeout
;
6557 const struct cred
*old_creds
= NULL
;
6561 linked_timeout
= io_prep_linked_timeout(req
);
6563 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
6564 (req
->work
.flags
& IO_WQ_WORK_CREDS
) &&
6565 req
->work
.identity
->creds
!= current_cred()) {
6567 revert_creds(old_creds
);
6568 if (old_creds
== req
->work
.identity
->creds
)
6569 old_creds
= NULL
; /* restored original creds */
6571 old_creds
= override_creds(req
->work
.identity
->creds
);
6574 ret
= io_issue_sqe(req
, true, cs
);
6577 * We async punt it if the file wasn't marked NOWAIT, or if the file
6578 * doesn't support non-blocking read/write attempts
6580 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6581 if (!io_arm_poll_handler(req
)) {
6583 * Queued up for async execution, worker will release
6584 * submit reference when the iocb is actually submitted.
6586 io_queue_async_work(req
);
6590 io_queue_linked_timeout(linked_timeout
);
6591 } else if (likely(!ret
)) {
6592 /* drop submission reference */
6593 req
= io_put_req_find_next(req
);
6595 io_queue_linked_timeout(linked_timeout
);
6598 if (!(req
->flags
& REQ_F_FORCE_ASYNC
))
6600 io_queue_async_work(req
);
6603 /* un-prep timeout, so it'll be killed as any other linked */
6604 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6605 req_set_fail_links(req
);
6607 io_req_complete(req
, ret
);
6611 revert_creds(old_creds
);
6614 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6615 struct io_comp_state
*cs
)
6619 ret
= io_req_defer(req
, sqe
);
6621 if (ret
!= -EIOCBQUEUED
) {
6623 req_set_fail_links(req
);
6625 io_req_complete(req
, ret
);
6627 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6628 if (!req
->async_data
) {
6629 ret
= io_req_defer_prep(req
, sqe
);
6633 io_queue_async_work(req
);
6636 ret
= io_req_prep(req
, sqe
);
6640 __io_queue_sqe(req
, cs
);
6644 static inline void io_queue_link_head(struct io_kiocb
*req
,
6645 struct io_comp_state
*cs
)
6647 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6649 io_req_complete(req
, -ECANCELED
);
6651 io_queue_sqe(req
, NULL
, cs
);
6654 struct io_submit_link
{
6655 struct io_kiocb
*head
;
6656 struct io_kiocb
*last
;
6659 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6660 struct io_submit_link
*link
, struct io_comp_state
*cs
)
6662 struct io_ring_ctx
*ctx
= req
->ctx
;
6666 * If we already have a head request, queue this one for async
6667 * submittal once the head completes. If we don't have a head but
6668 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6669 * submitted sync once the chain is complete. If none of those
6670 * conditions are true (normal request), then just queue it.
6673 struct io_kiocb
*head
= link
->head
;
6676 * Taking sequential execution of a link, draining both sides
6677 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6678 * requests in the link. So, it drains the head and the
6679 * next after the link request. The last one is done via
6680 * drain_next flag to persist the effect across calls.
6682 if (req
->flags
& REQ_F_IO_DRAIN
) {
6683 head
->flags
|= REQ_F_IO_DRAIN
;
6684 ctx
->drain_next
= 1;
6686 ret
= io_req_defer_prep(req
, sqe
);
6687 if (unlikely(ret
)) {
6688 /* fail even hard links since we don't submit */
6689 head
->flags
|= REQ_F_FAIL_LINK
;
6692 trace_io_uring_link(ctx
, req
, head
);
6693 link
->last
->link
= req
;
6696 /* last request of a link, enqueue the link */
6697 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6698 io_queue_link_head(head
, cs
);
6702 if (unlikely(ctx
->drain_next
)) {
6703 req
->flags
|= REQ_F_IO_DRAIN
;
6704 ctx
->drain_next
= 0;
6706 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6707 ret
= io_req_defer_prep(req
, sqe
);
6709 req
->flags
|= REQ_F_FAIL_LINK
;
6713 io_queue_sqe(req
, sqe
, cs
);
6721 * Batched submission is done, ensure local IO is flushed out.
6723 static void io_submit_state_end(struct io_submit_state
*state
)
6725 if (!list_empty(&state
->comp
.list
))
6726 io_submit_flush_completions(&state
->comp
);
6727 if (state
->plug_started
)
6728 blk_finish_plug(&state
->plug
);
6729 io_state_file_put(state
);
6730 if (state
->free_reqs
)
6731 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
6735 * Start submission side cache.
6737 static void io_submit_state_start(struct io_submit_state
*state
,
6738 struct io_ring_ctx
*ctx
, unsigned int max_ios
)
6740 state
->plug_started
= false;
6742 INIT_LIST_HEAD(&state
->comp
.list
);
6743 state
->comp
.ctx
= ctx
;
6744 state
->free_reqs
= 0;
6745 state
->file_refs
= 0;
6746 state
->ios_left
= max_ios
;
6749 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6751 struct io_rings
*rings
= ctx
->rings
;
6754 * Ensure any loads from the SQEs are done at this point,
6755 * since once we write the new head, the application could
6756 * write new data to them.
6758 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6762 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6763 * that is mapped by userspace. This means that care needs to be taken to
6764 * ensure that reads are stable, as we cannot rely on userspace always
6765 * being a good citizen. If members of the sqe are validated and then later
6766 * used, it's important that those reads are done through READ_ONCE() to
6767 * prevent a re-load down the line.
6769 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6771 u32
*sq_array
= ctx
->sq_array
;
6775 * The cached sq head (or cq tail) serves two purposes:
6777 * 1) allows us to batch the cost of updating the user visible
6779 * 2) allows the kernel side to track the head on its own, even
6780 * though the application is the one updating it.
6782 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
6783 if (likely(head
< ctx
->sq_entries
))
6784 return &ctx
->sq_sqes
[head
];
6786 /* drop invalid entries */
6787 ctx
->cached_sq_dropped
++;
6788 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6792 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
6794 ctx
->cached_sq_head
++;
6798 * Check SQE restrictions (opcode and flags).
6800 * Returns 'true' if SQE is allowed, 'false' otherwise.
6802 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6803 struct io_kiocb
*req
,
6804 unsigned int sqe_flags
)
6806 if (!ctx
->restricted
)
6809 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6812 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6813 ctx
->restrictions
.sqe_flags_required
)
6816 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6817 ctx
->restrictions
.sqe_flags_required
))
6823 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6824 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6825 IOSQE_BUFFER_SELECT)
6827 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6828 const struct io_uring_sqe
*sqe
,
6829 struct io_submit_state
*state
)
6831 unsigned int sqe_flags
;
6834 req
->opcode
= READ_ONCE(sqe
->opcode
);
6835 req
->user_data
= READ_ONCE(sqe
->user_data
);
6836 req
->async_data
= NULL
;
6841 req
->fixed_file_refs
= NULL
;
6842 /* one is dropped after submission, the other at completion */
6843 refcount_set(&req
->refs
, 2);
6844 req
->task
= current
;
6847 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6850 if (unlikely(io_sq_thread_acquire_mm_files(ctx
, req
)))
6853 sqe_flags
= READ_ONCE(sqe
->flags
);
6854 /* enforce forwards compatibility on users */
6855 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6858 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6861 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6862 !io_op_defs
[req
->opcode
].buffer_select
)
6865 id
= READ_ONCE(sqe
->personality
);
6867 struct io_identity
*iod
;
6869 iod
= idr_find(&ctx
->personality_idr
, id
);
6872 refcount_inc(&iod
->count
);
6874 __io_req_init_async(req
);
6875 get_cred(iod
->creds
);
6876 req
->work
.identity
= iod
;
6877 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
6880 /* same numerical values with corresponding REQ_F_*, safe to copy */
6881 req
->flags
|= sqe_flags
;
6884 * Plug now if we have more than 1 IO left after this, and the target
6885 * is potentially a read/write to block based storage.
6887 if (!state
->plug_started
&& state
->ios_left
> 1 &&
6888 io_op_defs
[req
->opcode
].plug
) {
6889 blk_start_plug(&state
->plug
);
6890 state
->plug_started
= true;
6894 if (io_op_defs
[req
->opcode
].needs_file
) {
6895 bool fixed
= req
->flags
& REQ_F_FIXED_FILE
;
6897 req
->file
= io_file_get(state
, req
, READ_ONCE(sqe
->fd
), fixed
);
6898 if (unlikely(!req
->file
&&
6899 !io_op_defs
[req
->opcode
].needs_file_no_error
))
6907 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6909 struct io_submit_state state
;
6910 struct io_submit_link link
;
6911 int i
, submitted
= 0;
6913 /* if we have a backlog and couldn't flush it all, return BUSY */
6914 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6915 if (!__io_cqring_overflow_flush(ctx
, false, NULL
, NULL
))
6919 /* make sure SQ entry isn't read before tail */
6920 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6922 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6925 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6926 refcount_add(nr
, ¤t
->usage
);
6928 io_submit_state_start(&state
, ctx
, nr
);
6931 for (i
= 0; i
< nr
; i
++) {
6932 const struct io_uring_sqe
*sqe
;
6933 struct io_kiocb
*req
;
6936 sqe
= io_get_sqe(ctx
);
6937 if (unlikely(!sqe
)) {
6938 io_consume_sqe(ctx
);
6941 req
= io_alloc_req(ctx
, &state
);
6942 if (unlikely(!req
)) {
6944 submitted
= -EAGAIN
;
6947 io_consume_sqe(ctx
);
6948 /* will complete beyond this point, count as submitted */
6951 err
= io_init_req(ctx
, req
, sqe
, &state
);
6952 if (unlikely(err
)) {
6955 io_req_complete(req
, err
);
6959 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6960 true, io_async_submit(ctx
));
6961 err
= io_submit_sqe(req
, sqe
, &link
, &state
.comp
);
6966 if (unlikely(submitted
!= nr
)) {
6967 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6968 struct io_uring_task
*tctx
= current
->io_uring
;
6969 int unused
= nr
- ref_used
;
6971 percpu_ref_put_many(&ctx
->refs
, unused
);
6972 percpu_counter_sub(&tctx
->inflight
, unused
);
6973 put_task_struct_many(current
, unused
);
6976 io_queue_link_head(link
.head
, &state
.comp
);
6977 io_submit_state_end(&state
);
6979 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6980 io_commit_sqring(ctx
);
6985 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6987 /* Tell userspace we may need a wakeup call */
6988 spin_lock_irq(&ctx
->completion_lock
);
6989 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6990 spin_unlock_irq(&ctx
->completion_lock
);
6993 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6995 spin_lock_irq(&ctx
->completion_lock
);
6996 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6997 spin_unlock_irq(&ctx
->completion_lock
);
7000 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
7002 unsigned int to_submit
;
7005 to_submit
= io_sqring_entries(ctx
);
7006 /* if we're handling multiple rings, cap submit size for fairness */
7007 if (cap_entries
&& to_submit
> 8)
7010 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
7011 unsigned nr_events
= 0;
7013 mutex_lock(&ctx
->uring_lock
);
7014 if (!list_empty(&ctx
->iopoll_list
))
7015 io_do_iopoll(ctx
, &nr_events
, 0);
7017 if (to_submit
&& !ctx
->sqo_dead
&&
7018 likely(!percpu_ref_is_dying(&ctx
->refs
)))
7019 ret
= io_submit_sqes(ctx
, to_submit
);
7020 mutex_unlock(&ctx
->uring_lock
);
7023 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
7024 wake_up(&ctx
->sqo_sq_wait
);
7029 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
7031 struct io_ring_ctx
*ctx
;
7032 unsigned sq_thread_idle
= 0;
7034 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7035 if (sq_thread_idle
< ctx
->sq_thread_idle
)
7036 sq_thread_idle
= ctx
->sq_thread_idle
;
7039 sqd
->sq_thread_idle
= sq_thread_idle
;
7042 static void io_sqd_init_new(struct io_sq_data
*sqd
)
7044 struct io_ring_ctx
*ctx
;
7046 while (!list_empty(&sqd
->ctx_new_list
)) {
7047 ctx
= list_first_entry(&sqd
->ctx_new_list
, struct io_ring_ctx
, sqd_list
);
7048 list_move_tail(&ctx
->sqd_list
, &sqd
->ctx_list
);
7049 complete(&ctx
->sq_thread_comp
);
7052 io_sqd_update_thread_idle(sqd
);
7055 static int io_sq_thread(void *data
)
7057 struct cgroup_subsys_state
*cur_css
= NULL
;
7058 struct files_struct
*old_files
= current
->files
;
7059 struct nsproxy
*old_nsproxy
= current
->nsproxy
;
7060 const struct cred
*old_cred
= NULL
;
7061 struct io_sq_data
*sqd
= data
;
7062 struct io_ring_ctx
*ctx
;
7063 unsigned long timeout
= 0;
7067 current
->files
= NULL
;
7068 current
->nsproxy
= NULL
;
7069 task_unlock(current
);
7071 while (!kthread_should_stop()) {
7073 bool cap_entries
, sqt_spin
, needs_sched
;
7076 * Any changes to the sqd lists are synchronized through the
7077 * kthread parking. This synchronizes the thread vs users,
7078 * the users are synchronized on the sqd->ctx_lock.
7080 if (kthread_should_park()) {
7083 * When sq thread is unparked, in case the previous park operation
7084 * comes from io_put_sq_data(), which means that sq thread is going
7085 * to be stopped, so here needs to have a check.
7087 if (kthread_should_stop())
7091 if (unlikely(!list_empty(&sqd
->ctx_new_list
))) {
7092 io_sqd_init_new(sqd
);
7093 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7097 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
7098 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7099 if (current
->cred
!= ctx
->creds
) {
7101 revert_creds(old_cred
);
7102 old_cred
= override_creds(ctx
->creds
);
7104 io_sq_thread_associate_blkcg(ctx
, &cur_css
);
7106 current
->loginuid
= ctx
->loginuid
;
7107 current
->sessionid
= ctx
->sessionid
;
7110 ret
= __io_sq_thread(ctx
, cap_entries
);
7111 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
7114 io_sq_thread_drop_mm_files();
7117 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
7119 io_sq_thread_drop_mm_files();
7122 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7126 if (kthread_should_park())
7130 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
7131 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7132 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
7133 !list_empty_careful(&ctx
->iopoll_list
)) {
7134 needs_sched
= false;
7137 if (io_sqring_entries(ctx
)) {
7138 needs_sched
= false;
7144 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7145 io_ring_set_wakeup_flag(ctx
);
7148 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7149 io_ring_clear_wakeup_flag(ctx
);
7152 finish_wait(&sqd
->wait
, &wait
);
7153 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7157 io_sq_thread_drop_mm_files();
7160 io_sq_thread_unassociate_blkcg();
7162 revert_creds(old_cred
);
7165 current
->files
= old_files
;
7166 current
->nsproxy
= old_nsproxy
;
7167 task_unlock(current
);
7174 struct io_wait_queue
{
7175 struct wait_queue_entry wq
;
7176 struct io_ring_ctx
*ctx
;
7178 unsigned nr_timeouts
;
7181 static inline bool io_should_wake(struct io_wait_queue
*iowq
)
7183 struct io_ring_ctx
*ctx
= iowq
->ctx
;
7186 * Wake up if we have enough events, or if a timeout occurred since we
7187 * started waiting. For timeouts, we always want to return to userspace,
7188 * regardless of event count.
7190 return io_cqring_events(ctx
) >= iowq
->to_wait
||
7191 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
7194 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
7195 int wake_flags
, void *key
)
7197 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
7201 * Cannot safely flush overflowed CQEs from here, ensure we wake up
7202 * the task, and the next invocation will do it.
7204 if (io_should_wake(iowq
) || test_bit(0, &iowq
->ctx
->cq_check_overflow
))
7205 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
7209 static int io_run_task_work_sig(void)
7211 if (io_run_task_work())
7213 if (!signal_pending(current
))
7215 if (test_tsk_thread_flag(current
, TIF_NOTIFY_SIGNAL
))
7216 return -ERESTARTSYS
;
7221 * Wait until events become available, if we don't already have some. The
7222 * application must reap them itself, as they reside on the shared cq ring.
7224 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
7225 const sigset_t __user
*sig
, size_t sigsz
,
7226 struct __kernel_timespec __user
*uts
)
7228 struct io_wait_queue iowq
= {
7231 .func
= io_wake_function
,
7232 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
7235 .to_wait
= min_events
,
7237 struct io_rings
*rings
= ctx
->rings
;
7238 struct timespec64 ts
;
7239 signed long timeout
= 0;
7243 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
7244 if (io_cqring_events(ctx
) >= min_events
)
7246 if (!io_run_task_work())
7251 #ifdef CONFIG_COMPAT
7252 if (in_compat_syscall())
7253 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
7257 ret
= set_user_sigmask(sig
, sigsz
);
7264 if (get_timespec64(&ts
, uts
))
7266 timeout
= timespec64_to_jiffies(&ts
);
7269 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
7270 trace_io_uring_cqring_wait(ctx
, min_events
);
7272 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
7273 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
7274 TASK_INTERRUPTIBLE
);
7275 /* make sure we run task_work before checking for signals */
7276 ret
= io_run_task_work_sig();
7278 finish_wait(&ctx
->wait
, &iowq
.wq
);
7283 if (io_should_wake(&iowq
))
7285 if (test_bit(0, &ctx
->cq_check_overflow
)) {
7286 finish_wait(&ctx
->wait
, &iowq
.wq
);
7290 timeout
= schedule_timeout(timeout
);
7299 finish_wait(&ctx
->wait
, &iowq
.wq
);
7301 restore_saved_sigmask_unless(ret
== -EINTR
);
7303 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7306 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7308 #if defined(CONFIG_UNIX)
7309 if (ctx
->ring_sock
) {
7310 struct sock
*sock
= ctx
->ring_sock
->sk
;
7311 struct sk_buff
*skb
;
7313 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7319 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7322 file
= io_file_from_index(ctx
, i
);
7329 static void io_file_ref_kill(struct percpu_ref
*ref
)
7331 struct fixed_file_data
*data
;
7333 data
= container_of(ref
, struct fixed_file_data
, refs
);
7334 complete(&data
->done
);
7337 static void io_sqe_files_set_node(struct fixed_file_data
*file_data
,
7338 struct fixed_file_ref_node
*ref_node
)
7340 spin_lock_bh(&file_data
->lock
);
7341 file_data
->node
= ref_node
;
7342 list_add_tail(&ref_node
->node
, &file_data
->ref_list
);
7343 spin_unlock_bh(&file_data
->lock
);
7344 percpu_ref_get(&file_data
->refs
);
7347 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7349 struct fixed_file_data
*data
= ctx
->file_data
;
7350 struct fixed_file_ref_node
*backup_node
, *ref_node
= NULL
;
7351 unsigned nr_tables
, i
;
7356 backup_node
= alloc_fixed_file_ref_node(ctx
);
7360 spin_lock_bh(&data
->lock
);
7361 ref_node
= data
->node
;
7362 spin_unlock_bh(&data
->lock
);
7364 percpu_ref_kill(&ref_node
->refs
);
7366 percpu_ref_kill(&data
->refs
);
7368 /* wait for all refs nodes to complete */
7369 flush_delayed_work(&ctx
->file_put_work
);
7371 ret
= wait_for_completion_interruptible(&data
->done
);
7374 ret
= io_run_task_work_sig();
7376 percpu_ref_resurrect(&data
->refs
);
7377 reinit_completion(&data
->done
);
7378 io_sqe_files_set_node(data
, backup_node
);
7383 __io_sqe_files_unregister(ctx
);
7384 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
7385 for (i
= 0; i
< nr_tables
; i
++)
7386 kfree(data
->table
[i
].files
);
7388 percpu_ref_exit(&data
->refs
);
7390 ctx
->file_data
= NULL
;
7391 ctx
->nr_user_files
= 0;
7392 destroy_fixed_file_ref_node(backup_node
);
7396 static void io_put_sq_data(struct io_sq_data
*sqd
)
7398 if (refcount_dec_and_test(&sqd
->refs
)) {
7400 * The park is a bit of a work-around, without it we get
7401 * warning spews on shutdown with SQPOLL set and affinity
7402 * set to a single CPU.
7405 kthread_park(sqd
->thread
);
7406 kthread_stop(sqd
->thread
);
7413 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7415 struct io_ring_ctx
*ctx_attach
;
7416 struct io_sq_data
*sqd
;
7419 f
= fdget(p
->wq_fd
);
7421 return ERR_PTR(-ENXIO
);
7422 if (f
.file
->f_op
!= &io_uring_fops
) {
7424 return ERR_PTR(-EINVAL
);
7427 ctx_attach
= f
.file
->private_data
;
7428 sqd
= ctx_attach
->sq_data
;
7431 return ERR_PTR(-EINVAL
);
7434 refcount_inc(&sqd
->refs
);
7439 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
)
7441 struct io_sq_data
*sqd
;
7443 if (p
->flags
& IORING_SETUP_ATTACH_WQ
)
7444 return io_attach_sq_data(p
);
7446 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7448 return ERR_PTR(-ENOMEM
);
7450 refcount_set(&sqd
->refs
, 1);
7451 INIT_LIST_HEAD(&sqd
->ctx_list
);
7452 INIT_LIST_HEAD(&sqd
->ctx_new_list
);
7453 mutex_init(&sqd
->ctx_lock
);
7454 mutex_init(&sqd
->lock
);
7455 init_waitqueue_head(&sqd
->wait
);
7459 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7460 __releases(&sqd
->lock
)
7464 kthread_unpark(sqd
->thread
);
7465 mutex_unlock(&sqd
->lock
);
7468 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7469 __acquires(&sqd
->lock
)
7473 mutex_lock(&sqd
->lock
);
7474 kthread_park(sqd
->thread
);
7477 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
7479 struct io_sq_data
*sqd
= ctx
->sq_data
;
7484 * We may arrive here from the error branch in
7485 * io_sq_offload_create() where the kthread is created
7486 * without being waked up, thus wake it up now to make
7487 * sure the wait will complete.
7489 wake_up_process(sqd
->thread
);
7490 wait_for_completion(&ctx
->sq_thread_comp
);
7492 io_sq_thread_park(sqd
);
7495 mutex_lock(&sqd
->ctx_lock
);
7496 list_del(&ctx
->sqd_list
);
7497 io_sqd_update_thread_idle(sqd
);
7498 mutex_unlock(&sqd
->ctx_lock
);
7501 io_sq_thread_unpark(sqd
);
7503 io_put_sq_data(sqd
);
7504 ctx
->sq_data
= NULL
;
7508 static void io_finish_async(struct io_ring_ctx
*ctx
)
7510 io_sq_thread_stop(ctx
);
7513 io_wq_destroy(ctx
->io_wq
);
7518 #if defined(CONFIG_UNIX)
7520 * Ensure the UNIX gc is aware of our file set, so we are certain that
7521 * the io_uring can be safely unregistered on process exit, even if we have
7522 * loops in the file referencing.
7524 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7526 struct sock
*sk
= ctx
->ring_sock
->sk
;
7527 struct scm_fp_list
*fpl
;
7528 struct sk_buff
*skb
;
7531 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7535 skb
= alloc_skb(0, GFP_KERNEL
);
7544 fpl
->user
= get_uid(ctx
->user
);
7545 for (i
= 0; i
< nr
; i
++) {
7546 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7550 fpl
->fp
[nr_files
] = get_file(file
);
7551 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7556 fpl
->max
= SCM_MAX_FD
;
7557 fpl
->count
= nr_files
;
7558 UNIXCB(skb
).fp
= fpl
;
7559 skb
->destructor
= unix_destruct_scm
;
7560 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7561 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7563 for (i
= 0; i
< nr_files
; i
++)
7574 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7575 * causes regular reference counting to break down. We rely on the UNIX
7576 * garbage collection to take care of this problem for us.
7578 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7580 unsigned left
, total
;
7584 left
= ctx
->nr_user_files
;
7586 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7588 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7592 total
+= this_files
;
7598 while (total
< ctx
->nr_user_files
) {
7599 struct file
*file
= io_file_from_index(ctx
, total
);
7609 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7615 static int io_sqe_alloc_file_tables(struct fixed_file_data
*file_data
,
7616 unsigned nr_tables
, unsigned nr_files
)
7620 for (i
= 0; i
< nr_tables
; i
++) {
7621 struct fixed_file_table
*table
= &file_data
->table
[i
];
7622 unsigned this_files
;
7624 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7625 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
7629 nr_files
-= this_files
;
7635 for (i
= 0; i
< nr_tables
; i
++) {
7636 struct fixed_file_table
*table
= &file_data
->table
[i
];
7637 kfree(table
->files
);
7642 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
7644 #if defined(CONFIG_UNIX)
7645 struct sock
*sock
= ctx
->ring_sock
->sk
;
7646 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7647 struct sk_buff
*skb
;
7650 __skb_queue_head_init(&list
);
7653 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7654 * remove this entry and rearrange the file array.
7656 skb
= skb_dequeue(head
);
7658 struct scm_fp_list
*fp
;
7660 fp
= UNIXCB(skb
).fp
;
7661 for (i
= 0; i
< fp
->count
; i
++) {
7664 if (fp
->fp
[i
] != file
)
7667 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7668 left
= fp
->count
- 1 - i
;
7670 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7671 left
* sizeof(struct file
*));
7678 __skb_queue_tail(&list
, skb
);
7688 __skb_queue_tail(&list
, skb
);
7690 skb
= skb_dequeue(head
);
7693 if (skb_peek(&list
)) {
7694 spin_lock_irq(&head
->lock
);
7695 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7696 __skb_queue_tail(head
, skb
);
7697 spin_unlock_irq(&head
->lock
);
7704 struct io_file_put
{
7705 struct list_head list
;
7709 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
7711 struct fixed_file_data
*file_data
= ref_node
->file_data
;
7712 struct io_ring_ctx
*ctx
= file_data
->ctx
;
7713 struct io_file_put
*pfile
, *tmp
;
7715 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
7716 list_del(&pfile
->list
);
7717 io_ring_file_put(ctx
, pfile
->file
);
7721 percpu_ref_exit(&ref_node
->refs
);
7723 percpu_ref_put(&file_data
->refs
);
7726 static void io_file_put_work(struct work_struct
*work
)
7728 struct io_ring_ctx
*ctx
;
7729 struct llist_node
*node
;
7731 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
7732 node
= llist_del_all(&ctx
->file_put_llist
);
7735 struct fixed_file_ref_node
*ref_node
;
7736 struct llist_node
*next
= node
->next
;
7738 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
7739 __io_file_put_work(ref_node
);
7744 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
7746 struct fixed_file_ref_node
*ref_node
;
7747 struct fixed_file_data
*data
;
7748 struct io_ring_ctx
*ctx
;
7749 bool first_add
= false;
7752 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
7753 data
= ref_node
->file_data
;
7756 spin_lock_bh(&data
->lock
);
7757 ref_node
->done
= true;
7759 while (!list_empty(&data
->ref_list
)) {
7760 ref_node
= list_first_entry(&data
->ref_list
,
7761 struct fixed_file_ref_node
, node
);
7762 /* recycle ref nodes in order */
7763 if (!ref_node
->done
)
7765 list_del(&ref_node
->node
);
7766 first_add
|= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
7768 spin_unlock_bh(&data
->lock
);
7770 if (percpu_ref_is_dying(&data
->refs
))
7774 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
7776 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
7779 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
7780 struct io_ring_ctx
*ctx
)
7782 struct fixed_file_ref_node
*ref_node
;
7784 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7788 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
7793 INIT_LIST_HEAD(&ref_node
->node
);
7794 INIT_LIST_HEAD(&ref_node
->file_list
);
7795 ref_node
->file_data
= ctx
->file_data
;
7796 ref_node
->done
= false;
7800 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
7802 percpu_ref_exit(&ref_node
->refs
);
7806 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7809 __s32 __user
*fds
= (__s32 __user
*) arg
;
7810 unsigned nr_tables
, i
;
7812 int fd
, ret
= -ENOMEM
;
7813 struct fixed_file_ref_node
*ref_node
;
7814 struct fixed_file_data
*file_data
;
7820 if (nr_args
> IORING_MAX_FIXED_FILES
)
7823 file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
7826 file_data
->ctx
= ctx
;
7827 init_completion(&file_data
->done
);
7828 INIT_LIST_HEAD(&file_data
->ref_list
);
7829 spin_lock_init(&file_data
->lock
);
7831 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7832 file_data
->table
= kcalloc(nr_tables
, sizeof(*file_data
->table
),
7834 if (!file_data
->table
)
7837 if (percpu_ref_init(&file_data
->refs
, io_file_ref_kill
,
7838 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
7841 if (io_sqe_alloc_file_tables(file_data
, nr_tables
, nr_args
))
7843 ctx
->file_data
= file_data
;
7845 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7846 struct fixed_file_table
*table
;
7849 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7853 /* allow sparse sets */
7863 * Don't allow io_uring instances to be registered. If UNIX
7864 * isn't enabled, then this causes a reference cycle and this
7865 * instance can never get freed. If UNIX is enabled we'll
7866 * handle it just fine, but there's still no point in allowing
7867 * a ring fd as it doesn't support regular read/write anyway.
7869 if (file
->f_op
== &io_uring_fops
) {
7873 table
= &file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7874 index
= i
& IORING_FILE_TABLE_MASK
;
7875 table
->files
[index
] = file
;
7878 ret
= io_sqe_files_scm(ctx
);
7880 io_sqe_files_unregister(ctx
);
7884 ref_node
= alloc_fixed_file_ref_node(ctx
);
7886 io_sqe_files_unregister(ctx
);
7890 io_sqe_files_set_node(file_data
, ref_node
);
7893 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7894 file
= io_file_from_index(ctx
, i
);
7898 for (i
= 0; i
< nr_tables
; i
++)
7899 kfree(file_data
->table
[i
].files
);
7900 ctx
->nr_user_files
= 0;
7902 percpu_ref_exit(&file_data
->refs
);
7904 kfree(file_data
->table
);
7906 ctx
->file_data
= NULL
;
7910 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7913 #if defined(CONFIG_UNIX)
7914 struct sock
*sock
= ctx
->ring_sock
->sk
;
7915 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7916 struct sk_buff
*skb
;
7919 * See if we can merge this file into an existing skb SCM_RIGHTS
7920 * file set. If there's no room, fall back to allocating a new skb
7921 * and filling it in.
7923 spin_lock_irq(&head
->lock
);
7924 skb
= skb_peek(head
);
7926 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7928 if (fpl
->count
< SCM_MAX_FD
) {
7929 __skb_unlink(skb
, head
);
7930 spin_unlock_irq(&head
->lock
);
7931 fpl
->fp
[fpl
->count
] = get_file(file
);
7932 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7934 spin_lock_irq(&head
->lock
);
7935 __skb_queue_head(head
, skb
);
7940 spin_unlock_irq(&head
->lock
);
7947 return __io_sqe_files_scm(ctx
, 1, index
);
7953 static int io_queue_file_removal(struct fixed_file_data
*data
,
7956 struct io_file_put
*pfile
;
7957 struct fixed_file_ref_node
*ref_node
= data
->node
;
7959 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
7964 list_add(&pfile
->list
, &ref_node
->file_list
);
7969 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7970 struct io_uring_files_update
*up
,
7973 struct fixed_file_data
*data
= ctx
->file_data
;
7974 struct fixed_file_ref_node
*ref_node
;
7979 bool needs_switch
= false;
7981 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7983 if (done
> ctx
->nr_user_files
)
7986 ref_node
= alloc_fixed_file_ref_node(ctx
);
7991 fds
= u64_to_user_ptr(up
->fds
);
7993 struct fixed_file_table
*table
;
7997 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
8001 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
8002 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
8003 index
= i
& IORING_FILE_TABLE_MASK
;
8004 if (table
->files
[index
]) {
8005 file
= table
->files
[index
];
8006 err
= io_queue_file_removal(data
, file
);
8009 table
->files
[index
] = NULL
;
8010 needs_switch
= true;
8019 * Don't allow io_uring instances to be registered. If
8020 * UNIX isn't enabled, then this causes a reference
8021 * cycle and this instance can never get freed. If UNIX
8022 * is enabled we'll handle it just fine, but there's
8023 * still no point in allowing a ring fd as it doesn't
8024 * support regular read/write anyway.
8026 if (file
->f_op
== &io_uring_fops
) {
8031 table
->files
[index
] = file
;
8032 err
= io_sqe_file_register(ctx
, file
, i
);
8034 table
->files
[index
] = NULL
;
8045 percpu_ref_kill(&data
->node
->refs
);
8046 io_sqe_files_set_node(data
, ref_node
);
8048 destroy_fixed_file_ref_node(ref_node
);
8050 return done
? done
: err
;
8053 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
8056 struct io_uring_files_update up
;
8058 if (!ctx
->file_data
)
8062 if (copy_from_user(&up
, arg
, sizeof(up
)))
8067 return __io_sqe_files_update(ctx
, &up
, nr_args
);
8070 static void io_free_work(struct io_wq_work
*work
)
8072 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8074 /* Consider that io_steal_work() relies on this ref */
8078 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
8079 struct io_uring_params
*p
)
8081 struct io_wq_data data
;
8083 struct io_ring_ctx
*ctx_attach
;
8084 unsigned int concurrency
;
8087 data
.user
= ctx
->user
;
8088 data
.free_work
= io_free_work
;
8089 data
.do_work
= io_wq_submit_work
;
8091 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
8092 /* Do QD, or 4 * CPUS, whatever is smallest */
8093 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
8095 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
8096 if (IS_ERR(ctx
->io_wq
)) {
8097 ret
= PTR_ERR(ctx
->io_wq
);
8103 f
= fdget(p
->wq_fd
);
8107 if (f
.file
->f_op
!= &io_uring_fops
) {
8112 ctx_attach
= f
.file
->private_data
;
8113 /* @io_wq is protected by holding the fd */
8114 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
8119 ctx
->io_wq
= ctx_attach
->io_wq
;
8125 static int io_uring_alloc_task_context(struct task_struct
*task
)
8127 struct io_uring_task
*tctx
;
8130 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
8131 if (unlikely(!tctx
))
8134 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
8135 if (unlikely(ret
)) {
8141 init_waitqueue_head(&tctx
->wait
);
8143 atomic_set(&tctx
->in_idle
, 0);
8144 tctx
->sqpoll
= false;
8145 io_init_identity(&tctx
->__identity
);
8146 tctx
->identity
= &tctx
->__identity
;
8147 task
->io_uring
= tctx
;
8151 void __io_uring_free(struct task_struct
*tsk
)
8153 struct io_uring_task
*tctx
= tsk
->io_uring
;
8155 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
8156 WARN_ON_ONCE(refcount_read(&tctx
->identity
->count
) != 1);
8157 if (tctx
->identity
!= &tctx
->__identity
)
8158 kfree(tctx
->identity
);
8159 percpu_counter_destroy(&tctx
->inflight
);
8161 tsk
->io_uring
= NULL
;
8164 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
8165 struct io_uring_params
*p
)
8169 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8170 struct io_sq_data
*sqd
;
8173 if (!capable(CAP_SYS_ADMIN
) && !capable(CAP_SYS_NICE
))
8176 sqd
= io_get_sq_data(p
);
8183 io_sq_thread_park(sqd
);
8184 mutex_lock(&sqd
->ctx_lock
);
8185 list_add(&ctx
->sqd_list
, &sqd
->ctx_new_list
);
8186 mutex_unlock(&sqd
->ctx_lock
);
8187 io_sq_thread_unpark(sqd
);
8189 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
8190 if (!ctx
->sq_thread_idle
)
8191 ctx
->sq_thread_idle
= HZ
;
8196 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8197 int cpu
= p
->sq_thread_cpu
;
8200 if (cpu
>= nr_cpu_ids
)
8202 if (!cpu_online(cpu
))
8205 sqd
->thread
= kthread_create_on_cpu(io_sq_thread
, sqd
,
8206 cpu
, "io_uring-sq");
8208 sqd
->thread
= kthread_create(io_sq_thread
, sqd
,
8211 if (IS_ERR(sqd
->thread
)) {
8212 ret
= PTR_ERR(sqd
->thread
);
8216 ret
= io_uring_alloc_task_context(sqd
->thread
);
8219 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8220 /* Can't have SQ_AFF without SQPOLL */
8226 ret
= io_init_wq_offload(ctx
, p
);
8232 io_finish_async(ctx
);
8236 static void io_sq_offload_start(struct io_ring_ctx
*ctx
)
8238 struct io_sq_data
*sqd
= ctx
->sq_data
;
8240 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && sqd
->thread
)
8241 wake_up_process(sqd
->thread
);
8244 static inline void __io_unaccount_mem(struct user_struct
*user
,
8245 unsigned long nr_pages
)
8247 atomic_long_sub(nr_pages
, &user
->locked_vm
);
8250 static inline int __io_account_mem(struct user_struct
*user
,
8251 unsigned long nr_pages
)
8253 unsigned long page_limit
, cur_pages
, new_pages
;
8255 /* Don't allow more pages than we can safely lock */
8256 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
8259 cur_pages
= atomic_long_read(&user
->locked_vm
);
8260 new_pages
= cur_pages
+ nr_pages
;
8261 if (new_pages
> page_limit
)
8263 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
8264 new_pages
) != cur_pages
);
8269 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
8270 enum io_mem_account acct
)
8273 __io_unaccount_mem(ctx
->user
, nr_pages
);
8275 if (ctx
->mm_account
) {
8276 if (acct
== ACCT_LOCKED
) {
8277 mmap_write_lock(ctx
->mm_account
);
8278 ctx
->mm_account
->locked_vm
-= nr_pages
;
8279 mmap_write_unlock(ctx
->mm_account
);
8280 }else if (acct
== ACCT_PINNED
) {
8281 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8286 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
8287 enum io_mem_account acct
)
8291 if (ctx
->limit_mem
) {
8292 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8297 if (ctx
->mm_account
) {
8298 if (acct
== ACCT_LOCKED
) {
8299 mmap_write_lock(ctx
->mm_account
);
8300 ctx
->mm_account
->locked_vm
+= nr_pages
;
8301 mmap_write_unlock(ctx
->mm_account
);
8302 } else if (acct
== ACCT_PINNED
) {
8303 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8310 static void io_mem_free(void *ptr
)
8317 page
= virt_to_head_page(ptr
);
8318 if (put_page_testzero(page
))
8319 free_compound_page(page
);
8322 static void *io_mem_alloc(size_t size
)
8324 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8327 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8330 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8333 struct io_rings
*rings
;
8334 size_t off
, sq_array_size
;
8336 off
= struct_size(rings
, cqes
, cq_entries
);
8337 if (off
== SIZE_MAX
)
8341 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8349 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8350 if (sq_array_size
== SIZE_MAX
)
8353 if (check_add_overflow(off
, sq_array_size
, &off
))
8359 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
8363 pages
= (size_t)1 << get_order(
8364 rings_size(sq_entries
, cq_entries
, NULL
));
8365 pages
+= (size_t)1 << get_order(
8366 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
8371 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
8375 if (!ctx
->user_bufs
)
8378 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8379 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8381 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
8382 unpin_user_page(imu
->bvec
[j
].bv_page
);
8384 if (imu
->acct_pages
)
8385 io_unaccount_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8390 kfree(ctx
->user_bufs
);
8391 ctx
->user_bufs
= NULL
;
8392 ctx
->nr_user_bufs
= 0;
8396 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8397 void __user
*arg
, unsigned index
)
8399 struct iovec __user
*src
;
8401 #ifdef CONFIG_COMPAT
8403 struct compat_iovec __user
*ciovs
;
8404 struct compat_iovec ciov
;
8406 ciovs
= (struct compat_iovec __user
*) arg
;
8407 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8410 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8411 dst
->iov_len
= ciov
.iov_len
;
8415 src
= (struct iovec __user
*) arg
;
8416 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8422 * Not super efficient, but this is just a registration time. And we do cache
8423 * the last compound head, so generally we'll only do a full search if we don't
8426 * We check if the given compound head page has already been accounted, to
8427 * avoid double accounting it. This allows us to account the full size of the
8428 * page, not just the constituent pages of a huge page.
8430 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8431 int nr_pages
, struct page
*hpage
)
8435 /* check current page array */
8436 for (i
= 0; i
< nr_pages
; i
++) {
8437 if (!PageCompound(pages
[i
]))
8439 if (compound_head(pages
[i
]) == hpage
)
8443 /* check previously registered pages */
8444 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8445 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8447 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8448 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8450 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8458 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8459 int nr_pages
, struct io_mapped_ubuf
*imu
,
8460 struct page
**last_hpage
)
8464 for (i
= 0; i
< nr_pages
; i
++) {
8465 if (!PageCompound(pages
[i
])) {
8470 hpage
= compound_head(pages
[i
]);
8471 if (hpage
== *last_hpage
)
8473 *last_hpage
= hpage
;
8474 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8476 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8480 if (!imu
->acct_pages
)
8483 ret
= io_account_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8485 imu
->acct_pages
= 0;
8489 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8492 struct vm_area_struct
**vmas
= NULL
;
8493 struct page
**pages
= NULL
;
8494 struct page
*last_hpage
= NULL
;
8495 int i
, j
, got_pages
= 0;
8500 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8503 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
8505 if (!ctx
->user_bufs
)
8508 for (i
= 0; i
< nr_args
; i
++) {
8509 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8510 unsigned long off
, start
, end
, ubuf
;
8515 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8520 * Don't impose further limits on the size and buffer
8521 * constraints here, we'll -EINVAL later when IO is
8522 * submitted if they are wrong.
8525 if (!iov
.iov_base
|| !iov
.iov_len
)
8528 /* arbitrary limit, but we need something */
8529 if (iov
.iov_len
> SZ_1G
)
8532 ubuf
= (unsigned long) iov
.iov_base
;
8533 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8534 start
= ubuf
>> PAGE_SHIFT
;
8535 nr_pages
= end
- start
;
8538 if (!pages
|| nr_pages
> got_pages
) {
8541 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
8543 vmas
= kvmalloc_array(nr_pages
,
8544 sizeof(struct vm_area_struct
*),
8546 if (!pages
|| !vmas
) {
8550 got_pages
= nr_pages
;
8553 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8560 mmap_read_lock(current
->mm
);
8561 pret
= pin_user_pages(ubuf
, nr_pages
,
8562 FOLL_WRITE
| FOLL_LONGTERM
,
8564 if (pret
== nr_pages
) {
8565 /* don't support file backed memory */
8566 for (j
= 0; j
< nr_pages
; j
++) {
8567 struct vm_area_struct
*vma
= vmas
[j
];
8570 !is_file_hugepages(vma
->vm_file
)) {
8576 ret
= pret
< 0 ? pret
: -EFAULT
;
8578 mmap_read_unlock(current
->mm
);
8581 * if we did partial map, or found file backed vmas,
8582 * release any pages we did get
8585 unpin_user_pages(pages
, pret
);
8590 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, &last_hpage
);
8592 unpin_user_pages(pages
, pret
);
8597 off
= ubuf
& ~PAGE_MASK
;
8599 for (j
= 0; j
< nr_pages
; j
++) {
8602 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8603 imu
->bvec
[j
].bv_page
= pages
[j
];
8604 imu
->bvec
[j
].bv_len
= vec_len
;
8605 imu
->bvec
[j
].bv_offset
= off
;
8609 /* store original address for later verification */
8611 imu
->len
= iov
.iov_len
;
8612 imu
->nr_bvecs
= nr_pages
;
8614 ctx
->nr_user_bufs
++;
8622 io_sqe_buffer_unregister(ctx
);
8626 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8628 __s32 __user
*fds
= arg
;
8634 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8637 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8638 if (IS_ERR(ctx
->cq_ev_fd
)) {
8639 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8640 ctx
->cq_ev_fd
= NULL
;
8647 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8649 if (ctx
->cq_ev_fd
) {
8650 eventfd_ctx_put(ctx
->cq_ev_fd
);
8651 ctx
->cq_ev_fd
= NULL
;
8658 static int __io_destroy_buffers(int id
, void *p
, void *data
)
8660 struct io_ring_ctx
*ctx
= data
;
8661 struct io_buffer
*buf
= p
;
8663 __io_remove_buffers(ctx
, buf
, id
, -1U);
8667 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8669 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
8670 idr_destroy(&ctx
->io_buffer_idr
);
8673 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8675 io_finish_async(ctx
);
8676 io_sqe_buffer_unregister(ctx
);
8678 if (ctx
->sqo_task
) {
8679 put_task_struct(ctx
->sqo_task
);
8680 ctx
->sqo_task
= NULL
;
8681 mmdrop(ctx
->mm_account
);
8682 ctx
->mm_account
= NULL
;
8685 #ifdef CONFIG_BLK_CGROUP
8686 if (ctx
->sqo_blkcg_css
)
8687 css_put(ctx
->sqo_blkcg_css
);
8690 io_sqe_files_unregister(ctx
);
8691 io_eventfd_unregister(ctx
);
8692 io_destroy_buffers(ctx
);
8693 idr_destroy(&ctx
->personality_idr
);
8695 #if defined(CONFIG_UNIX)
8696 if (ctx
->ring_sock
) {
8697 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8698 sock_release(ctx
->ring_sock
);
8702 io_mem_free(ctx
->rings
);
8703 io_mem_free(ctx
->sq_sqes
);
8705 percpu_ref_exit(&ctx
->refs
);
8706 free_uid(ctx
->user
);
8707 put_cred(ctx
->creds
);
8708 kfree(ctx
->cancel_hash
);
8709 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
8713 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8715 struct io_ring_ctx
*ctx
= file
->private_data
;
8718 poll_wait(file
, &ctx
->cq_wait
, wait
);
8720 * synchronizes with barrier from wq_has_sleeper call in
8724 if (!io_sqring_full(ctx
))
8725 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8726 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
8727 if (io_cqring_events(ctx
))
8728 mask
|= EPOLLIN
| EPOLLRDNORM
;
8733 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8735 struct io_ring_ctx
*ctx
= file
->private_data
;
8737 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8740 static int io_remove_personalities(int id
, void *p
, void *data
)
8742 struct io_ring_ctx
*ctx
= data
;
8743 struct io_identity
*iod
;
8745 iod
= idr_remove(&ctx
->personality_idr
, id
);
8747 put_cred(iod
->creds
);
8748 if (refcount_dec_and_test(&iod
->count
))
8754 static void io_ring_exit_work(struct work_struct
*work
)
8756 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
8760 * If we're doing polled IO and end up having requests being
8761 * submitted async (out-of-line), then completions can come in while
8762 * we're waiting for refs to drop. We need to reap these manually,
8763 * as nobody else will be looking for them.
8766 __io_uring_cancel_task_requests(ctx
, NULL
);
8767 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8768 io_ring_ctx_free(ctx
);
8771 static bool io_cancel_ctx_cb(struct io_wq_work
*work
, void *data
)
8773 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8775 return req
->ctx
== data
;
8778 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8780 mutex_lock(&ctx
->uring_lock
);
8781 percpu_ref_kill(&ctx
->refs
);
8783 if (WARN_ON_ONCE((ctx
->flags
& IORING_SETUP_SQPOLL
) && !ctx
->sqo_dead
))
8786 /* if force is set, the ring is going away. always drop after that */
8787 ctx
->cq_overflow_flushed
= 1;
8789 __io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8790 mutex_unlock(&ctx
->uring_lock
);
8792 io_kill_timeouts(ctx
, NULL
, NULL
);
8793 io_poll_remove_all(ctx
, NULL
, NULL
);
8796 io_wq_cancel_cb(ctx
->io_wq
, io_cancel_ctx_cb
, ctx
, true);
8798 /* if we failed setting up the ctx, we might not have any rings */
8799 io_iopoll_try_reap_events(ctx
);
8800 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
8803 * Do this upfront, so we won't have a grace period where the ring
8804 * is closed but resources aren't reaped yet. This can cause
8805 * spurious failure in setting up a new ring.
8807 io_unaccount_mem(ctx
, ring_pages(ctx
->sq_entries
, ctx
->cq_entries
),
8810 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8812 * Use system_unbound_wq to avoid spawning tons of event kworkers
8813 * if we're exiting a ton of rings at the same time. It just adds
8814 * noise and overhead, there's no discernable change in runtime
8815 * over using system_wq.
8817 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8820 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8822 struct io_ring_ctx
*ctx
= file
->private_data
;
8824 file
->private_data
= NULL
;
8825 io_ring_ctx_wait_and_kill(ctx
);
8829 struct io_task_cancel
{
8830 struct task_struct
*task
;
8831 struct files_struct
*files
;
8834 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8836 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8837 struct io_task_cancel
*cancel
= data
;
8840 if (cancel
->files
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
8841 unsigned long flags
;
8842 struct io_ring_ctx
*ctx
= req
->ctx
;
8844 /* protect against races with linked timeouts */
8845 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
8846 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8847 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
8849 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8854 static void io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8855 struct task_struct
*task
,
8856 struct files_struct
*files
)
8858 struct io_defer_entry
*de
= NULL
;
8861 spin_lock_irq(&ctx
->completion_lock
);
8862 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8863 if (io_match_task(de
->req
, task
, files
)) {
8864 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8868 spin_unlock_irq(&ctx
->completion_lock
);
8870 while (!list_empty(&list
)) {
8871 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8872 list_del_init(&de
->list
);
8873 req_set_fail_links(de
->req
);
8874 io_put_req(de
->req
);
8875 io_req_complete(de
->req
, -ECANCELED
);
8880 static int io_uring_count_inflight(struct io_ring_ctx
*ctx
,
8881 struct task_struct
*task
,
8882 struct files_struct
*files
)
8884 struct io_kiocb
*req
;
8887 spin_lock_irq(&ctx
->inflight_lock
);
8888 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
)
8889 cnt
+= io_match_task(req
, task
, files
);
8890 spin_unlock_irq(&ctx
->inflight_lock
);
8894 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8895 struct task_struct
*task
,
8896 struct files_struct
*files
)
8898 while (!list_empty_careful(&ctx
->inflight_list
)) {
8899 struct io_task_cancel cancel
= { .task
= task
, .files
= files
};
8903 inflight
= io_uring_count_inflight(ctx
, task
, files
);
8907 io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, &cancel
, true);
8908 io_poll_remove_all(ctx
, task
, files
);
8909 io_kill_timeouts(ctx
, task
, files
);
8910 io_cqring_overflow_flush(ctx
, true, task
, files
);
8911 /* cancellations _may_ trigger task work */
8914 prepare_to_wait(&task
->io_uring
->wait
, &wait
,
8915 TASK_UNINTERRUPTIBLE
);
8916 if (inflight
== io_uring_count_inflight(ctx
, task
, files
))
8918 finish_wait(&task
->io_uring
->wait
, &wait
);
8922 static void __io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8923 struct task_struct
*task
)
8926 struct io_task_cancel cancel
= { .task
= task
, .files
= NULL
, };
8927 enum io_wq_cancel cret
;
8931 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
,
8933 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
8936 /* SQPOLL thread does its own polling */
8937 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8938 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8939 io_iopoll_try_reap_events(ctx
);
8944 ret
|= io_poll_remove_all(ctx
, task
, NULL
);
8945 ret
|= io_kill_timeouts(ctx
, task
, NULL
);
8946 ret
|= io_run_task_work();
8953 static void io_disable_sqo_submit(struct io_ring_ctx
*ctx
)
8955 mutex_lock(&ctx
->uring_lock
);
8957 mutex_unlock(&ctx
->uring_lock
);
8959 /* make sure callers enter the ring to get error */
8961 io_ring_set_wakeup_flag(ctx
);
8965 * We need to iteratively cancel requests, in case a request has dependent
8966 * hard links. These persist even for failure of cancelations, hence keep
8967 * looping until none are found.
8969 static void io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8970 struct files_struct
*files
)
8972 struct task_struct
*task
= current
;
8974 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
) {
8975 io_disable_sqo_submit(ctx
);
8976 task
= ctx
->sq_data
->thread
;
8977 atomic_inc(&task
->io_uring
->in_idle
);
8978 io_sq_thread_park(ctx
->sq_data
);
8981 io_cancel_defer_files(ctx
, task
, files
);
8982 io_cqring_overflow_flush(ctx
, true, task
, files
);
8984 io_uring_cancel_files(ctx
, task
, files
);
8986 __io_uring_cancel_task_requests(ctx
, task
);
8988 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
) {
8989 atomic_dec(&task
->io_uring
->in_idle
);
8990 io_sq_thread_unpark(ctx
->sq_data
);
8995 * Note that this task has used io_uring. We use it for cancelation purposes.
8997 static int io_uring_add_task_file(struct io_ring_ctx
*ctx
, struct file
*file
)
8999 struct io_uring_task
*tctx
= current
->io_uring
;
9002 if (unlikely(!tctx
)) {
9003 ret
= io_uring_alloc_task_context(current
);
9006 tctx
= current
->io_uring
;
9008 if (tctx
->last
!= file
) {
9009 void *old
= xa_load(&tctx
->xa
, (unsigned long)file
);
9013 ret
= xa_err(xa_store(&tctx
->xa
, (unsigned long)file
,
9024 * This is race safe in that the task itself is doing this, hence it
9025 * cannot be going through the exit/cancel paths at the same time.
9026 * This cannot be modified while exit/cancel is running.
9028 if (!tctx
->sqpoll
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
9029 tctx
->sqpoll
= true;
9035 * Remove this io_uring_file -> task mapping.
9037 static void io_uring_del_task_file(struct file
*file
)
9039 struct io_uring_task
*tctx
= current
->io_uring
;
9041 if (tctx
->last
== file
)
9043 file
= xa_erase(&tctx
->xa
, (unsigned long)file
);
9048 static void io_uring_remove_task_files(struct io_uring_task
*tctx
)
9051 unsigned long index
;
9053 xa_for_each(&tctx
->xa
, index
, file
)
9054 io_uring_del_task_file(file
);
9057 void __io_uring_files_cancel(struct files_struct
*files
)
9059 struct io_uring_task
*tctx
= current
->io_uring
;
9061 unsigned long index
;
9063 /* make sure overflow events are dropped */
9064 atomic_inc(&tctx
->in_idle
);
9065 xa_for_each(&tctx
->xa
, index
, file
)
9066 io_uring_cancel_task_requests(file
->private_data
, files
);
9067 atomic_dec(&tctx
->in_idle
);
9070 io_uring_remove_task_files(tctx
);
9073 static s64
tctx_inflight(struct io_uring_task
*tctx
)
9075 unsigned long index
;
9079 inflight
= percpu_counter_sum(&tctx
->inflight
);
9084 * If we have SQPOLL rings, then we need to iterate and find them, and
9085 * add the pending count for those.
9087 xa_for_each(&tctx
->xa
, index
, file
) {
9088 struct io_ring_ctx
*ctx
= file
->private_data
;
9090 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9091 struct io_uring_task
*__tctx
= ctx
->sqo_task
->io_uring
;
9093 inflight
+= percpu_counter_sum(&__tctx
->inflight
);
9101 * Find any io_uring fd that this task has registered or done IO on, and cancel
9104 void __io_uring_task_cancel(void)
9106 struct io_uring_task
*tctx
= current
->io_uring
;
9110 /* make sure overflow events are dropped */
9111 atomic_inc(&tctx
->in_idle
);
9113 /* trigger io_disable_sqo_submit() */
9115 __io_uring_files_cancel(NULL
);
9118 /* read completions before cancelations */
9119 inflight
= tctx_inflight(tctx
);
9122 __io_uring_files_cancel(NULL
);
9124 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
9127 * If we've seen completions, retry without waiting. This
9128 * avoids a race where a completion comes in before we did
9129 * prepare_to_wait().
9131 if (inflight
== tctx_inflight(tctx
))
9133 finish_wait(&tctx
->wait
, &wait
);
9136 atomic_dec(&tctx
->in_idle
);
9138 io_uring_remove_task_files(tctx
);
9141 static int io_uring_flush(struct file
*file
, void *data
)
9143 struct io_uring_task
*tctx
= current
->io_uring
;
9144 struct io_ring_ctx
*ctx
= file
->private_data
;
9146 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
))
9147 io_uring_cancel_task_requests(ctx
, NULL
);
9152 /* we should have cancelled and erased it before PF_EXITING */
9153 WARN_ON_ONCE((current
->flags
& PF_EXITING
) &&
9154 xa_load(&tctx
->xa
, (unsigned long)file
));
9157 * fput() is pending, will be 2 if the only other ref is our potential
9158 * task file note. If the task is exiting, drop regardless of count.
9160 if (atomic_long_read(&file
->f_count
) != 2)
9163 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9164 /* there is only one file note, which is owned by sqo_task */
9165 WARN_ON_ONCE(ctx
->sqo_task
!= current
&&
9166 xa_load(&tctx
->xa
, (unsigned long)file
));
9167 /* sqo_dead check is for when this happens after cancellation */
9168 WARN_ON_ONCE(ctx
->sqo_task
== current
&& !ctx
->sqo_dead
&&
9169 !xa_load(&tctx
->xa
, (unsigned long)file
));
9171 io_disable_sqo_submit(ctx
);
9174 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
) || ctx
->sqo_task
== current
)
9175 io_uring_del_task_file(file
);
9179 static void *io_uring_validate_mmap_request(struct file
*file
,
9180 loff_t pgoff
, size_t sz
)
9182 struct io_ring_ctx
*ctx
= file
->private_data
;
9183 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9188 case IORING_OFF_SQ_RING
:
9189 case IORING_OFF_CQ_RING
:
9192 case IORING_OFF_SQES
:
9196 return ERR_PTR(-EINVAL
);
9199 page
= virt_to_head_page(ptr
);
9200 if (sz
> page_size(page
))
9201 return ERR_PTR(-EINVAL
);
9208 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9210 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9214 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9216 return PTR_ERR(ptr
);
9218 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9219 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9222 #else /* !CONFIG_MMU */
9224 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9226 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9229 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9231 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9234 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9235 unsigned long addr
, unsigned long len
,
9236 unsigned long pgoff
, unsigned long flags
)
9240 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9242 return PTR_ERR(ptr
);
9244 return (unsigned long) ptr
;
9247 #endif /* !CONFIG_MMU */
9249 static int io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9255 if (!io_sqring_full(ctx
))
9258 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9260 if (unlikely(ctx
->sqo_dead
)) {
9265 if (!io_sqring_full(ctx
))
9269 } while (!signal_pending(current
));
9271 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9276 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9277 struct __kernel_timespec __user
**ts
,
9278 const sigset_t __user
**sig
)
9280 struct io_uring_getevents_arg arg
;
9283 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9284 * is just a pointer to the sigset_t.
9286 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9287 *sig
= (const sigset_t __user
*) argp
;
9293 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9294 * timespec and sigset_t pointers if good.
9296 if (*argsz
!= sizeof(arg
))
9298 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9300 *sig
= u64_to_user_ptr(arg
.sigmask
);
9301 *argsz
= arg
.sigmask_sz
;
9302 *ts
= u64_to_user_ptr(arg
.ts
);
9306 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9307 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9310 struct io_ring_ctx
*ctx
;
9317 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9318 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
))
9326 if (f
.file
->f_op
!= &io_uring_fops
)
9330 ctx
= f
.file
->private_data
;
9331 if (!percpu_ref_tryget(&ctx
->refs
))
9335 if (ctx
->flags
& IORING_SETUP_R_DISABLED
)
9339 * For SQ polling, the thread will do all submissions and completions.
9340 * Just return the requested submit count, and wake the thread if
9344 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9345 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
9348 if (unlikely(ctx
->sqo_dead
))
9350 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9351 wake_up(&ctx
->sq_data
->wait
);
9352 if (flags
& IORING_ENTER_SQ_WAIT
) {
9353 ret
= io_sqpoll_wait_sq(ctx
);
9357 submitted
= to_submit
;
9358 } else if (to_submit
) {
9359 ret
= io_uring_add_task_file(ctx
, f
.file
);
9362 mutex_lock(&ctx
->uring_lock
);
9363 submitted
= io_submit_sqes(ctx
, to_submit
);
9364 mutex_unlock(&ctx
->uring_lock
);
9366 if (submitted
!= to_submit
)
9369 if (flags
& IORING_ENTER_GETEVENTS
) {
9370 const sigset_t __user
*sig
;
9371 struct __kernel_timespec __user
*ts
;
9373 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
9377 min_complete
= min(min_complete
, ctx
->cq_entries
);
9380 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9381 * space applications don't need to do io completion events
9382 * polling again, they can rely on io_sq_thread to do polling
9383 * work, which can reduce cpu usage and uring_lock contention.
9385 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
9386 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9387 ret
= io_iopoll_check(ctx
, min_complete
);
9389 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
9394 percpu_ref_put(&ctx
->refs
);
9397 return submitted
? submitted
: ret
;
9400 #ifdef CONFIG_PROC_FS
9401 static int io_uring_show_cred(int id
, void *p
, void *data
)
9403 struct io_identity
*iod
= p
;
9404 const struct cred
*cred
= iod
->creds
;
9405 struct seq_file
*m
= data
;
9406 struct user_namespace
*uns
= seq_user_ns(m
);
9407 struct group_info
*gi
;
9412 seq_printf(m
, "%5d\n", id
);
9413 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
9414 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
9415 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
9416 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
9417 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
9418 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
9419 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
9420 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
9421 seq_puts(m
, "\n\tGroups:\t");
9422 gi
= cred
->group_info
;
9423 for (g
= 0; g
< gi
->ngroups
; g
++) {
9424 seq_put_decimal_ull(m
, g
? " " : "",
9425 from_kgid_munged(uns
, gi
->gid
[g
]));
9427 seq_puts(m
, "\n\tCapEff:\t");
9428 cap
= cred
->cap_effective
;
9429 CAP_FOR_EACH_U32(__capi
)
9430 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
9435 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
9437 struct io_sq_data
*sq
= NULL
;
9442 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9443 * since fdinfo case grabs it in the opposite direction of normal use
9444 * cases. If we fail to get the lock, we just don't iterate any
9445 * structures that could be going away outside the io_uring mutex.
9447 has_lock
= mutex_trylock(&ctx
->uring_lock
);
9449 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
9452 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
9453 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
9454 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
9455 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
9456 struct fixed_file_table
*table
;
9459 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
9460 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
9462 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
9464 seq_printf(m
, "%5u: <none>\n", i
);
9466 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
9467 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
9468 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
9470 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
9471 (unsigned int) buf
->len
);
9473 if (has_lock
&& !idr_is_empty(&ctx
->personality_idr
)) {
9474 seq_printf(m
, "Personalities:\n");
9475 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
9477 seq_printf(m
, "PollList:\n");
9478 spin_lock_irq(&ctx
->completion_lock
);
9479 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9480 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9481 struct io_kiocb
*req
;
9483 hlist_for_each_entry(req
, list
, hash_node
)
9484 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9485 req
->task
->task_works
!= NULL
);
9487 spin_unlock_irq(&ctx
->completion_lock
);
9489 mutex_unlock(&ctx
->uring_lock
);
9492 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9494 struct io_ring_ctx
*ctx
= f
->private_data
;
9496 if (percpu_ref_tryget(&ctx
->refs
)) {
9497 __io_uring_show_fdinfo(ctx
, m
);
9498 percpu_ref_put(&ctx
->refs
);
9503 static const struct file_operations io_uring_fops
= {
9504 .release
= io_uring_release
,
9505 .flush
= io_uring_flush
,
9506 .mmap
= io_uring_mmap
,
9508 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9509 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9511 .poll
= io_uring_poll
,
9512 .fasync
= io_uring_fasync
,
9513 #ifdef CONFIG_PROC_FS
9514 .show_fdinfo
= io_uring_show_fdinfo
,
9518 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9519 struct io_uring_params
*p
)
9521 struct io_rings
*rings
;
9522 size_t size
, sq_array_offset
;
9524 /* make sure these are sane, as we already accounted them */
9525 ctx
->sq_entries
= p
->sq_entries
;
9526 ctx
->cq_entries
= p
->cq_entries
;
9528 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9529 if (size
== SIZE_MAX
)
9532 rings
= io_mem_alloc(size
);
9537 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9538 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9539 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9540 rings
->sq_ring_entries
= p
->sq_entries
;
9541 rings
->cq_ring_entries
= p
->cq_entries
;
9542 ctx
->sq_mask
= rings
->sq_ring_mask
;
9543 ctx
->cq_mask
= rings
->cq_ring_mask
;
9545 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9546 if (size
== SIZE_MAX
) {
9547 io_mem_free(ctx
->rings
);
9552 ctx
->sq_sqes
= io_mem_alloc(size
);
9553 if (!ctx
->sq_sqes
) {
9554 io_mem_free(ctx
->rings
);
9562 static int io_uring_install_fd(struct io_ring_ctx
*ctx
, struct file
*file
)
9566 fd
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9570 ret
= io_uring_add_task_file(ctx
, file
);
9575 fd_install(fd
, file
);
9580 * Allocate an anonymous fd, this is what constitutes the application
9581 * visible backing of an io_uring instance. The application mmaps this
9582 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9583 * we have to tie this fd to a socket for file garbage collection purposes.
9585 static struct file
*io_uring_get_file(struct io_ring_ctx
*ctx
)
9588 #if defined(CONFIG_UNIX)
9591 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9594 return ERR_PTR(ret
);
9597 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9598 O_RDWR
| O_CLOEXEC
);
9599 #if defined(CONFIG_UNIX)
9601 sock_release(ctx
->ring_sock
);
9602 ctx
->ring_sock
= NULL
;
9604 ctx
->ring_sock
->file
= file
;
9610 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9611 struct io_uring_params __user
*params
)
9613 struct user_struct
*user
= NULL
;
9614 struct io_ring_ctx
*ctx
;
9621 if (entries
> IORING_MAX_ENTRIES
) {
9622 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9624 entries
= IORING_MAX_ENTRIES
;
9628 * Use twice as many entries for the CQ ring. It's possible for the
9629 * application to drive a higher depth than the size of the SQ ring,
9630 * since the sqes are only used at submission time. This allows for
9631 * some flexibility in overcommitting a bit. If the application has
9632 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9633 * of CQ ring entries manually.
9635 p
->sq_entries
= roundup_pow_of_two(entries
);
9636 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9638 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9639 * to a power-of-two, if it isn't already. We do NOT impose
9640 * any cq vs sq ring sizing.
9644 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9645 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9647 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9649 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9650 if (p
->cq_entries
< p
->sq_entries
)
9653 p
->cq_entries
= 2 * p
->sq_entries
;
9656 user
= get_uid(current_user());
9657 limit_mem
= !capable(CAP_IPC_LOCK
);
9660 ret
= __io_account_mem(user
,
9661 ring_pages(p
->sq_entries
, p
->cq_entries
));
9668 ctx
= io_ring_ctx_alloc(p
);
9671 __io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
9676 ctx
->compat
= in_compat_syscall();
9678 ctx
->creds
= get_current_cred();
9680 ctx
->loginuid
= current
->loginuid
;
9681 ctx
->sessionid
= current
->sessionid
;
9683 ctx
->sqo_task
= get_task_struct(current
);
9686 * This is just grabbed for accounting purposes. When a process exits,
9687 * the mm is exited and dropped before the files, hence we need to hang
9688 * on to this mm purely for the purposes of being able to unaccount
9689 * memory (locked/pinned vm). It's not used for anything else.
9691 mmgrab(current
->mm
);
9692 ctx
->mm_account
= current
->mm
;
9694 #ifdef CONFIG_BLK_CGROUP
9696 * The sq thread will belong to the original cgroup it was inited in.
9697 * If the cgroup goes offline (e.g. disabling the io controller), then
9698 * issued bios will be associated with the closest cgroup later in the
9702 ctx
->sqo_blkcg_css
= blkcg_css();
9703 ret
= css_tryget_online(ctx
->sqo_blkcg_css
);
9706 /* don't init against a dying cgroup, have the user try again */
9707 ctx
->sqo_blkcg_css
= NULL
;
9714 * Account memory _before_ installing the file descriptor. Once
9715 * the descriptor is installed, it can get closed at any time. Also
9716 * do this before hitting the general error path, as ring freeing
9717 * will un-account as well.
9719 io_account_mem(ctx
, ring_pages(p
->sq_entries
, p
->cq_entries
),
9721 ctx
->limit_mem
= limit_mem
;
9723 ret
= io_allocate_scq_urings(ctx
, p
);
9727 ret
= io_sq_offload_create(ctx
, p
);
9731 if (!(p
->flags
& IORING_SETUP_R_DISABLED
))
9732 io_sq_offload_start(ctx
);
9734 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9735 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9736 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9737 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9738 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9739 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9740 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9741 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9743 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9744 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9745 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9746 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9747 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9748 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9749 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9750 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9752 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9753 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9754 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9755 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
9756 IORING_FEAT_EXT_ARG
;
9758 if (copy_to_user(params
, p
, sizeof(*p
))) {
9763 file
= io_uring_get_file(ctx
);
9765 ret
= PTR_ERR(file
);
9770 * Install ring fd as the very last thing, so we don't risk someone
9771 * having closed it before we finish setup
9773 ret
= io_uring_install_fd(ctx
, file
);
9775 io_disable_sqo_submit(ctx
);
9776 /* fput will clean it up */
9781 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9784 io_disable_sqo_submit(ctx
);
9785 io_ring_ctx_wait_and_kill(ctx
);
9790 * Sets up an aio uring context, and returns the fd. Applications asks for a
9791 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9792 * params structure passed in.
9794 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9796 struct io_uring_params p
;
9799 if (copy_from_user(&p
, params
, sizeof(p
)))
9801 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9806 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9807 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9808 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9809 IORING_SETUP_R_DISABLED
))
9812 return io_uring_create(entries
, &p
, params
);
9815 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9816 struct io_uring_params __user
*, params
)
9818 return io_uring_setup(entries
, params
);
9821 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9823 struct io_uring_probe
*p
;
9827 size
= struct_size(p
, ops
, nr_args
);
9828 if (size
== SIZE_MAX
)
9830 p
= kzalloc(size
, GFP_KERNEL
);
9835 if (copy_from_user(p
, arg
, size
))
9838 if (memchr_inv(p
, 0, size
))
9841 p
->last_op
= IORING_OP_LAST
- 1;
9842 if (nr_args
> IORING_OP_LAST
)
9843 nr_args
= IORING_OP_LAST
;
9845 for (i
= 0; i
< nr_args
; i
++) {
9847 if (!io_op_defs
[i
].not_supported
)
9848 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9853 if (copy_to_user(arg
, p
, size
))
9860 static int io_register_personality(struct io_ring_ctx
*ctx
)
9862 struct io_identity
*id
;
9865 id
= kmalloc(sizeof(*id
), GFP_KERNEL
);
9869 io_init_identity(id
);
9870 id
->creds
= get_current_cred();
9872 ret
= idr_alloc_cyclic(&ctx
->personality_idr
, id
, 1, USHRT_MAX
, GFP_KERNEL
);
9874 put_cred(id
->creds
);
9880 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
9882 struct io_identity
*iod
;
9884 iod
= idr_remove(&ctx
->personality_idr
, id
);
9886 put_cred(iod
->creds
);
9887 if (refcount_dec_and_test(&iod
->count
))
9895 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9896 unsigned int nr_args
)
9898 struct io_uring_restriction
*res
;
9902 /* Restrictions allowed only if rings started disabled */
9903 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9906 /* We allow only a single restrictions registration */
9907 if (ctx
->restrictions
.registered
)
9910 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9913 size
= array_size(nr_args
, sizeof(*res
));
9914 if (size
== SIZE_MAX
)
9917 res
= memdup_user(arg
, size
);
9919 return PTR_ERR(res
);
9923 for (i
= 0; i
< nr_args
; i
++) {
9924 switch (res
[i
].opcode
) {
9925 case IORING_RESTRICTION_REGISTER_OP
:
9926 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9931 __set_bit(res
[i
].register_op
,
9932 ctx
->restrictions
.register_op
);
9934 case IORING_RESTRICTION_SQE_OP
:
9935 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9940 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9942 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9943 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9945 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9946 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9955 /* Reset all restrictions if an error happened */
9957 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9959 ctx
->restrictions
.registered
= true;
9965 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9967 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9970 if (ctx
->restrictions
.registered
)
9971 ctx
->restricted
= 1;
9973 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9975 io_sq_offload_start(ctx
);
9980 static bool io_register_op_must_quiesce(int op
)
9983 case IORING_UNREGISTER_FILES
:
9984 case IORING_REGISTER_FILES_UPDATE
:
9985 case IORING_REGISTER_PROBE
:
9986 case IORING_REGISTER_PERSONALITY
:
9987 case IORING_UNREGISTER_PERSONALITY
:
9994 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
9995 void __user
*arg
, unsigned nr_args
)
9996 __releases(ctx
->uring_lock
)
9997 __acquires(ctx
->uring_lock
)
10002 * We're inside the ring mutex, if the ref is already dying, then
10003 * someone else killed the ctx or is already going through
10004 * io_uring_register().
10006 if (percpu_ref_is_dying(&ctx
->refs
))
10009 if (io_register_op_must_quiesce(opcode
)) {
10010 percpu_ref_kill(&ctx
->refs
);
10013 * Drop uring mutex before waiting for references to exit. If
10014 * another thread is currently inside io_uring_enter() it might
10015 * need to grab the uring_lock to make progress. If we hold it
10016 * here across the drain wait, then we can deadlock. It's safe
10017 * to drop the mutex here, since no new references will come in
10018 * after we've killed the percpu ref.
10020 mutex_unlock(&ctx
->uring_lock
);
10022 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
10025 ret
= io_run_task_work_sig();
10030 mutex_lock(&ctx
->uring_lock
);
10033 percpu_ref_resurrect(&ctx
->refs
);
10038 if (ctx
->restricted
) {
10039 if (opcode
>= IORING_REGISTER_LAST
) {
10044 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
10051 case IORING_REGISTER_BUFFERS
:
10052 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
10054 case IORING_UNREGISTER_BUFFERS
:
10056 if (arg
|| nr_args
)
10058 ret
= io_sqe_buffer_unregister(ctx
);
10060 case IORING_REGISTER_FILES
:
10061 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
10063 case IORING_UNREGISTER_FILES
:
10065 if (arg
|| nr_args
)
10067 ret
= io_sqe_files_unregister(ctx
);
10069 case IORING_REGISTER_FILES_UPDATE
:
10070 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
10072 case IORING_REGISTER_EVENTFD
:
10073 case IORING_REGISTER_EVENTFD_ASYNC
:
10077 ret
= io_eventfd_register(ctx
, arg
);
10080 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
10081 ctx
->eventfd_async
= 1;
10083 ctx
->eventfd_async
= 0;
10085 case IORING_UNREGISTER_EVENTFD
:
10087 if (arg
|| nr_args
)
10089 ret
= io_eventfd_unregister(ctx
);
10091 case IORING_REGISTER_PROBE
:
10093 if (!arg
|| nr_args
> 256)
10095 ret
= io_probe(ctx
, arg
, nr_args
);
10097 case IORING_REGISTER_PERSONALITY
:
10099 if (arg
|| nr_args
)
10101 ret
= io_register_personality(ctx
);
10103 case IORING_UNREGISTER_PERSONALITY
:
10107 ret
= io_unregister_personality(ctx
, nr_args
);
10109 case IORING_REGISTER_ENABLE_RINGS
:
10111 if (arg
|| nr_args
)
10113 ret
= io_register_enable_rings(ctx
);
10115 case IORING_REGISTER_RESTRICTIONS
:
10116 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
10124 if (io_register_op_must_quiesce(opcode
)) {
10125 /* bring the ctx back to life */
10126 percpu_ref_reinit(&ctx
->refs
);
10128 reinit_completion(&ctx
->ref_comp
);
10133 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
10134 void __user
*, arg
, unsigned int, nr_args
)
10136 struct io_ring_ctx
*ctx
;
10145 if (f
.file
->f_op
!= &io_uring_fops
)
10148 ctx
= f
.file
->private_data
;
10150 mutex_lock(&ctx
->uring_lock
);
10151 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
10152 mutex_unlock(&ctx
->uring_lock
);
10153 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
10154 ctx
->cq_ev_fd
!= NULL
, ret
);
10160 static int __init
io_uring_init(void)
10162 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10163 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10164 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10167 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10168 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10169 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
10170 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
10171 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
10172 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
10173 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
10174 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
10175 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
10176 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
10177 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
10178 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
10179 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
10180 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
10181 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
10182 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
10183 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
10184 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
10185 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
10186 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
10187 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
10188 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
10189 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
10190 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
10191 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
10192 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
10193 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
10194 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
10195 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
10196 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
10197 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
10199 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
10200 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
10201 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
10204 __initcall(io_uring_init
);