1 // SPDX-License-Identifier: GPL-2.0
3 * Shared application/kernel submission and completion ring pairs, for
4 * supporting fast/efficient IO.
6 * A note on the read/write ordering memory barriers that are matched between
7 * the application and kernel side.
9 * After the application reads the CQ ring tail, it must use an
10 * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
11 * before writing the tail (using smp_load_acquire to read the tail will
12 * do). It also needs a smp_mb() before updating CQ head (ordering the
13 * entry load(s) with the head store), pairing with an implicit barrier
14 * through a control-dependency in io_get_cqring (smp_store_release to
15 * store head will do). Failure to do so could lead to reading invalid
18 * Likewise, the application must use an appropriate smp_wmb() before
19 * writing the SQ tail (ordering SQ entry stores with the tail store),
20 * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
21 * to store the tail will do). And it needs a barrier ordering the SQ
22 * head load before writing new SQ entries (smp_load_acquire to read
25 * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
26 * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
27 * updating the SQ tail; a full memory barrier smp_mb() is needed
30 * Also see the examples in the liburing library:
32 * git://git.kernel.dk/liburing
34 * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
35 * from data shared between the kernel and application. This is done both
36 * for ordering purposes, but also to ensure that once a value is loaded from
37 * data that the application could potentially modify, it remains stable.
39 * Copyright (C) 2018-2019 Jens Axboe
40 * Copyright (c) 2018-2019 Christoph Hellwig
42 #include <linux/kernel.h>
43 #include <linux/init.h>
44 #include <linux/errno.h>
45 #include <linux/syscalls.h>
46 #include <linux/compat.h>
47 #include <net/compat.h>
48 #include <linux/refcount.h>
49 #include <linux/uio.h>
50 #include <linux/bits.h>
52 #include <linux/sched/signal.h>
54 #include <linux/file.h>
55 #include <linux/fdtable.h>
57 #include <linux/mman.h>
58 #include <linux/percpu.h>
59 #include <linux/slab.h>
60 #include <linux/kthread.h>
61 #include <linux/blkdev.h>
62 #include <linux/bvec.h>
63 #include <linux/net.h>
65 #include <net/af_unix.h>
67 #include <linux/anon_inodes.h>
68 #include <linux/sched/mm.h>
69 #include <linux/uaccess.h>
70 #include <linux/nospec.h>
71 #include <linux/sizes.h>
72 #include <linux/hugetlb.h>
73 #include <linux/highmem.h>
74 #include <linux/namei.h>
75 #include <linux/fsnotify.h>
76 #include <linux/fadvise.h>
77 #include <linux/eventpoll.h>
78 #include <linux/fs_struct.h>
79 #include <linux/splice.h>
80 #include <linux/task_work.h>
81 #include <linux/pagemap.h>
82 #include <linux/io_uring.h>
83 #include <linux/blk-cgroup.h>
84 #include <linux/audit.h>
86 #define CREATE_TRACE_POINTS
87 #include <trace/events/io_uring.h>
89 #include <uapi/linux/io_uring.h>
94 #define IORING_MAX_ENTRIES 32768
95 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
98 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
100 #define IORING_FILE_TABLE_SHIFT 9
101 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
102 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
103 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
104 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
105 IORING_REGISTER_LAST + IORING_OP_LAST)
108 u32 head ____cacheline_aligned_in_smp
;
109 u32 tail ____cacheline_aligned_in_smp
;
113 * This data is shared with the application through the mmap at offsets
114 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
116 * The offsets to the member fields are published through struct
117 * io_sqring_offsets when calling io_uring_setup.
121 * Head and tail offsets into the ring; the offsets need to be
122 * masked to get valid indices.
124 * The kernel controls head of the sq ring and the tail of the cq ring,
125 * and the application controls tail of the sq ring and the head of the
128 struct io_uring sq
, cq
;
130 * Bitmasks to apply to head and tail offsets (constant, equals
133 u32 sq_ring_mask
, cq_ring_mask
;
134 /* Ring sizes (constant, power of 2) */
135 u32 sq_ring_entries
, cq_ring_entries
;
137 * Number of invalid entries dropped by the kernel due to
138 * invalid index stored in array
140 * Written by the kernel, shouldn't be modified by the
141 * application (i.e. get number of "new events" by comparing to
144 * After a new SQ head value was read by the application this
145 * counter includes all submissions that were dropped reaching
146 * the new SQ head (and possibly more).
152 * Written by the kernel, shouldn't be modified by the
155 * The application needs a full memory barrier before checking
156 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
162 * Written by the application, shouldn't be modified by the
167 * Number of completion events lost because the queue was full;
168 * this should be avoided by the application by making sure
169 * there are not more requests pending than there is space in
170 * the completion queue.
172 * Written by the kernel, shouldn't be modified by the
173 * application (i.e. get number of "new events" by comparing to
176 * As completion events come in out of order this counter is not
177 * ordered with any other data.
181 * Ring buffer of completion events.
183 * The kernel writes completion events fresh every time they are
184 * produced, so the application is allowed to modify pending
187 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
190 struct io_mapped_ubuf
{
193 struct bio_vec
*bvec
;
194 unsigned int nr_bvecs
;
195 unsigned long acct_pages
;
198 struct fixed_file_table
{
202 struct fixed_file_ref_node
{
203 struct percpu_ref refs
;
204 struct list_head node
;
205 struct list_head file_list
;
206 struct fixed_file_data
*file_data
;
207 struct llist_node llist
;
211 struct fixed_file_data
{
212 struct fixed_file_table
*table
;
213 struct io_ring_ctx
*ctx
;
215 struct fixed_file_ref_node
*node
;
216 struct percpu_ref refs
;
217 struct completion done
;
218 struct list_head ref_list
;
223 struct list_head list
;
229 struct io_restriction
{
230 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
231 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
232 u8 sqe_flags_allowed
;
233 u8 sqe_flags_required
;
241 /* ctx's that are using this sqd */
242 struct list_head ctx_list
;
243 struct list_head ctx_new_list
;
244 struct mutex ctx_lock
;
246 struct task_struct
*thread
;
247 struct wait_queue_head wait
;
249 unsigned sq_thread_idle
;
254 struct percpu_ref refs
;
255 } ____cacheline_aligned_in_smp
;
259 unsigned int compat
: 1;
260 unsigned int limit_mem
: 1;
261 unsigned int cq_overflow_flushed
: 1;
262 unsigned int drain_next
: 1;
263 unsigned int eventfd_async
: 1;
264 unsigned int restricted
: 1;
267 * Ring buffer of indices into array of io_uring_sqe, which is
268 * mmapped by the application using the IORING_OFF_SQES offset.
270 * This indirection could e.g. be used to assign fixed
271 * io_uring_sqe entries to operations and only submit them to
272 * the queue when needed.
274 * The kernel modifies neither the indices array nor the entries
278 unsigned cached_sq_head
;
281 unsigned sq_thread_idle
;
282 unsigned cached_sq_dropped
;
283 unsigned cached_cq_overflow
;
284 unsigned long sq_check_overflow
;
286 struct list_head defer_list
;
287 struct list_head timeout_list
;
288 struct list_head cq_overflow_list
;
290 struct io_uring_sqe
*sq_sqes
;
291 } ____cacheline_aligned_in_smp
;
293 struct io_rings
*rings
;
299 * For SQPOLL usage - we hold a reference to the parent task, so we
300 * have access to the ->files
302 struct task_struct
*sqo_task
;
304 /* Only used for accounting purposes */
305 struct mm_struct
*mm_account
;
307 #ifdef CONFIG_BLK_CGROUP
308 struct cgroup_subsys_state
*sqo_blkcg_css
;
311 struct io_sq_data
*sq_data
; /* if using sq thread polling */
313 struct wait_queue_head sqo_sq_wait
;
314 struct list_head sqd_list
;
317 * If used, fixed file set. Writers must ensure that ->refs is dead,
318 * readers must ensure that ->refs is alive as long as the file* is
319 * used. Only updated through io_uring_register(2).
321 struct fixed_file_data
*file_data
;
322 unsigned nr_user_files
;
324 /* if used, fixed mapped user buffers */
325 unsigned nr_user_bufs
;
326 struct io_mapped_ubuf
*user_bufs
;
328 struct user_struct
*user
;
330 const struct cred
*creds
;
334 unsigned int sessionid
;
337 struct completion ref_comp
;
338 struct completion sq_thread_comp
;
340 /* if all else fails... */
341 struct io_kiocb
*fallback_req
;
343 #if defined(CONFIG_UNIX)
344 struct socket
*ring_sock
;
347 struct idr io_buffer_idr
;
349 struct idr personality_idr
;
352 unsigned cached_cq_tail
;
355 atomic_t cq_timeouts
;
356 unsigned long cq_check_overflow
;
357 struct wait_queue_head cq_wait
;
358 struct fasync_struct
*cq_fasync
;
359 struct eventfd_ctx
*cq_ev_fd
;
360 } ____cacheline_aligned_in_smp
;
363 struct mutex uring_lock
;
364 wait_queue_head_t wait
;
365 } ____cacheline_aligned_in_smp
;
368 spinlock_t completion_lock
;
371 * ->iopoll_list is protected by the ctx->uring_lock for
372 * io_uring instances that don't use IORING_SETUP_SQPOLL.
373 * For SQPOLL, only the single threaded io_sq_thread() will
374 * manipulate the list, hence no extra locking is needed there.
376 struct list_head iopoll_list
;
377 struct hlist_head
*cancel_hash
;
378 unsigned cancel_hash_bits
;
379 bool poll_multi_file
;
381 spinlock_t inflight_lock
;
382 struct list_head inflight_list
;
383 } ____cacheline_aligned_in_smp
;
385 struct delayed_work file_put_work
;
386 struct llist_head file_put_llist
;
388 struct work_struct exit_work
;
389 struct io_restriction restrictions
;
393 * First field must be the file pointer in all the
394 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
396 struct io_poll_iocb
{
398 struct wait_queue_head
*head
;
402 struct wait_queue_entry wait
;
405 struct io_poll_remove
{
412 struct file
*put_file
;
416 struct io_timeout_data
{
417 struct io_kiocb
*req
;
418 struct hrtimer timer
;
419 struct timespec64 ts
;
420 enum hrtimer_mode mode
;
425 struct sockaddr __user
*addr
;
426 int __user
*addr_len
;
428 unsigned long nofile
;
448 struct list_head list
;
449 /* head of the link, used by linked timeouts only */
450 struct io_kiocb
*head
;
453 struct io_timeout_rem
{
458 struct timespec64 ts
;
463 /* NOTE: kiocb has the file as the first member, so don't do it here */
471 struct sockaddr __user
*addr
;
478 struct user_msghdr __user
*umsg
;
484 struct io_buffer
*kbuf
;
490 bool ignore_nonblock
;
491 struct filename
*filename
;
493 unsigned long nofile
;
496 struct io_files_update
{
522 struct epoll_event event
;
526 struct file
*file_out
;
527 struct file
*file_in
;
534 struct io_provide_buf
{
548 const char __user
*filename
;
549 struct statx __user
*buffer
;
561 struct filename
*oldpath
;
562 struct filename
*newpath
;
570 struct filename
*filename
;
573 struct io_completion
{
575 struct list_head list
;
579 struct io_async_connect
{
580 struct sockaddr_storage address
;
583 struct io_async_msghdr
{
584 struct iovec fast_iov
[UIO_FASTIOV
];
586 struct sockaddr __user
*uaddr
;
588 struct sockaddr_storage addr
;
592 struct iovec fast_iov
[UIO_FASTIOV
];
593 const struct iovec
*free_iovec
;
594 struct iov_iter iter
;
596 struct wait_page_queue wpq
;
600 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
601 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
602 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
603 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
604 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
605 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
611 REQ_F_LINK_TIMEOUT_BIT
,
613 REQ_F_NEED_CLEANUP_BIT
,
615 REQ_F_BUFFER_SELECTED_BIT
,
616 REQ_F_NO_FILE_TABLE_BIT
,
617 REQ_F_WORK_INITIALIZED_BIT
,
618 REQ_F_LTIMEOUT_ACTIVE_BIT
,
620 /* not a real bit, just to check we're not overflowing the space */
626 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
627 /* drain existing IO first */
628 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
630 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
631 /* doesn't sever on completion < 0 */
632 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
634 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
635 /* IOSQE_BUFFER_SELECT */
636 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
638 /* fail rest of links */
639 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
640 /* on inflight list */
641 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
642 /* read/write uses file position */
643 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
644 /* must not punt to workers */
645 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
646 /* has or had linked timeout */
647 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
649 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
651 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
652 /* already went through poll handler */
653 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
654 /* buffer already selected */
655 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
656 /* doesn't need file table for this request */
657 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
658 /* io_wq_work is initialized */
659 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
660 /* linked timeout is active, i.e. prepared by link's head */
661 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
665 struct io_poll_iocb poll
;
666 struct io_poll_iocb
*double_poll
;
670 * NOTE! Each of the iocb union members has the file pointer
671 * as the first entry in their struct definition. So you can
672 * access the file pointer through any of the sub-structs,
673 * or directly as just 'ki_filp' in this struct.
679 struct io_poll_iocb poll
;
680 struct io_poll_remove poll_remove
;
681 struct io_accept accept
;
683 struct io_cancel cancel
;
684 struct io_timeout timeout
;
685 struct io_timeout_rem timeout_rem
;
686 struct io_connect connect
;
687 struct io_sr_msg sr_msg
;
689 struct io_close close
;
690 struct io_files_update files_update
;
691 struct io_fadvise fadvise
;
692 struct io_madvise madvise
;
693 struct io_epoll epoll
;
694 struct io_splice splice
;
695 struct io_provide_buf pbuf
;
696 struct io_statx statx
;
697 struct io_shutdown shutdown
;
698 struct io_rename rename
;
699 struct io_unlink unlink
;
700 /* use only after cleaning per-op data, see io_clean_op() */
701 struct io_completion
compl;
704 /* opcode allocated if it needs to store data for async defer */
707 /* polled IO has completed */
713 struct io_ring_ctx
*ctx
;
716 struct task_struct
*task
;
719 struct io_kiocb
*link
;
720 struct percpu_ref
*fixed_file_refs
;
723 * 1. used with ctx->iopoll_list with reads/writes
724 * 2. to track reqs with ->files (see io_op_def::file_table)
726 struct list_head inflight_entry
;
727 struct callback_head task_work
;
728 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
729 struct hlist_node hash_node
;
730 struct async_poll
*apoll
;
731 struct io_wq_work work
;
734 struct io_defer_entry
{
735 struct list_head list
;
736 struct io_kiocb
*req
;
740 #define IO_IOPOLL_BATCH 8
742 struct io_comp_state
{
744 struct list_head list
;
745 struct io_ring_ctx
*ctx
;
748 struct io_submit_state
{
749 struct blk_plug plug
;
752 * io_kiocb alloc cache
754 void *reqs
[IO_IOPOLL_BATCH
];
755 unsigned int free_reqs
;
760 * Batch completion logic
762 struct io_comp_state comp
;
765 * File reference cache
769 unsigned int file_refs
;
770 unsigned int ios_left
;
774 /* needs req->file assigned */
775 unsigned needs_file
: 1;
776 /* don't fail if file grab fails */
777 unsigned needs_file_no_error
: 1;
778 /* hash wq insertion if file is a regular file */
779 unsigned hash_reg_file
: 1;
780 /* unbound wq insertion if file is a non-regular file */
781 unsigned unbound_nonreg_file
: 1;
782 /* opcode is not supported by this kernel */
783 unsigned not_supported
: 1;
784 /* set if opcode supports polled "wait" */
786 unsigned pollout
: 1;
787 /* op supports buffer selection */
788 unsigned buffer_select
: 1;
789 /* must always have async data allocated */
790 unsigned needs_async_data
: 1;
791 /* should block plug */
793 /* size of async data needed, if any */
794 unsigned short async_size
;
798 static const struct io_op_def io_op_defs
[] = {
799 [IORING_OP_NOP
] = {},
800 [IORING_OP_READV
] = {
802 .unbound_nonreg_file
= 1,
805 .needs_async_data
= 1,
807 .async_size
= sizeof(struct io_async_rw
),
808 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
810 [IORING_OP_WRITEV
] = {
813 .unbound_nonreg_file
= 1,
815 .needs_async_data
= 1,
817 .async_size
= sizeof(struct io_async_rw
),
818 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
821 [IORING_OP_FSYNC
] = {
823 .work_flags
= IO_WQ_WORK_BLKCG
,
825 [IORING_OP_READ_FIXED
] = {
827 .unbound_nonreg_file
= 1,
830 .async_size
= sizeof(struct io_async_rw
),
831 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
833 [IORING_OP_WRITE_FIXED
] = {
836 .unbound_nonreg_file
= 1,
839 .async_size
= sizeof(struct io_async_rw
),
840 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
|
843 [IORING_OP_POLL_ADD
] = {
845 .unbound_nonreg_file
= 1,
847 [IORING_OP_POLL_REMOVE
] = {},
848 [IORING_OP_SYNC_FILE_RANGE
] = {
850 .work_flags
= IO_WQ_WORK_BLKCG
,
852 [IORING_OP_SENDMSG
] = {
854 .unbound_nonreg_file
= 1,
856 .needs_async_data
= 1,
857 .async_size
= sizeof(struct io_async_msghdr
),
858 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
860 [IORING_OP_RECVMSG
] = {
862 .unbound_nonreg_file
= 1,
865 .needs_async_data
= 1,
866 .async_size
= sizeof(struct io_async_msghdr
),
867 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
869 [IORING_OP_TIMEOUT
] = {
870 .needs_async_data
= 1,
871 .async_size
= sizeof(struct io_timeout_data
),
872 .work_flags
= IO_WQ_WORK_MM
,
874 [IORING_OP_TIMEOUT_REMOVE
] = {
875 /* used by timeout updates' prep() */
876 .work_flags
= IO_WQ_WORK_MM
,
878 [IORING_OP_ACCEPT
] = {
880 .unbound_nonreg_file
= 1,
882 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
,
884 [IORING_OP_ASYNC_CANCEL
] = {},
885 [IORING_OP_LINK_TIMEOUT
] = {
886 .needs_async_data
= 1,
887 .async_size
= sizeof(struct io_timeout_data
),
888 .work_flags
= IO_WQ_WORK_MM
,
890 [IORING_OP_CONNECT
] = {
892 .unbound_nonreg_file
= 1,
894 .needs_async_data
= 1,
895 .async_size
= sizeof(struct io_async_connect
),
896 .work_flags
= IO_WQ_WORK_MM
,
898 [IORING_OP_FALLOCATE
] = {
900 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
,
902 [IORING_OP_OPENAT
] = {
903 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
|
904 IO_WQ_WORK_FS
| IO_WQ_WORK_MM
,
906 [IORING_OP_CLOSE
] = {
908 .needs_file_no_error
= 1,
909 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
,
911 [IORING_OP_FILES_UPDATE
] = {
912 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
,
914 [IORING_OP_STATX
] = {
915 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
|
916 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
920 .unbound_nonreg_file
= 1,
924 .async_size
= sizeof(struct io_async_rw
),
925 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
927 [IORING_OP_WRITE
] = {
929 .unbound_nonreg_file
= 1,
932 .async_size
= sizeof(struct io_async_rw
),
933 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
936 [IORING_OP_FADVISE
] = {
938 .work_flags
= IO_WQ_WORK_BLKCG
,
940 [IORING_OP_MADVISE
] = {
941 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
945 .unbound_nonreg_file
= 1,
947 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
951 .unbound_nonreg_file
= 1,
954 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
956 [IORING_OP_OPENAT2
] = {
957 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_FS
|
958 IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
960 [IORING_OP_EPOLL_CTL
] = {
961 .unbound_nonreg_file
= 1,
962 .work_flags
= IO_WQ_WORK_FILES
,
964 [IORING_OP_SPLICE
] = {
967 .unbound_nonreg_file
= 1,
968 .work_flags
= IO_WQ_WORK_BLKCG
,
970 [IORING_OP_PROVIDE_BUFFERS
] = {},
971 [IORING_OP_REMOVE_BUFFERS
] = {},
975 .unbound_nonreg_file
= 1,
977 [IORING_OP_SHUTDOWN
] = {
980 [IORING_OP_RENAMEAT
] = {
981 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
|
982 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
984 [IORING_OP_UNLINKAT
] = {
985 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
|
986 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
990 enum io_mem_account
{
995 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
996 struct io_comp_state
*cs
);
997 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
998 static void io_put_req(struct io_kiocb
*req
);
999 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
1000 static void io_double_put_req(struct io_kiocb
*req
);
1001 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
1002 static void __io_queue_linked_timeout(struct io_kiocb
*req
);
1003 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1004 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
1005 struct io_uring_files_update
*ip
,
1007 static void __io_clean_op(struct io_kiocb
*req
);
1008 static struct file
*io_file_get(struct io_submit_state
*state
,
1009 struct io_kiocb
*req
, int fd
, bool fixed
);
1010 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
);
1011 static void io_file_put_work(struct work_struct
*work
);
1013 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
1014 struct iovec
**iovec
, struct iov_iter
*iter
,
1016 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
1017 const struct iovec
*fast_iov
,
1018 struct iov_iter
*iter
, bool force
);
1020 static struct kmem_cache
*req_cachep
;
1022 static const struct file_operations io_uring_fops
;
1024 struct sock
*io_uring_get_socket(struct file
*file
)
1026 #if defined(CONFIG_UNIX)
1027 if (file
->f_op
== &io_uring_fops
) {
1028 struct io_ring_ctx
*ctx
= file
->private_data
;
1030 return ctx
->ring_sock
->sk
;
1035 EXPORT_SYMBOL(io_uring_get_socket
);
1037 #define io_for_each_link(pos, head) \
1038 for (pos = (head); pos; pos = pos->link)
1040 static inline void io_clean_op(struct io_kiocb
*req
)
1042 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
|
1047 static inline void io_set_resource_node(struct io_kiocb
*req
)
1049 struct io_ring_ctx
*ctx
= req
->ctx
;
1051 if (!req
->fixed_file_refs
) {
1052 req
->fixed_file_refs
= &ctx
->file_data
->node
->refs
;
1053 percpu_ref_get(req
->fixed_file_refs
);
1057 static bool io_match_task(struct io_kiocb
*head
,
1058 struct task_struct
*task
,
1059 struct files_struct
*files
)
1061 struct io_kiocb
*req
;
1063 if (task
&& head
->task
!= task
)
1068 io_for_each_link(req
, head
) {
1069 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
1070 (req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1071 req
->work
.identity
->files
== files
)
1077 static void io_sq_thread_drop_mm_files(void)
1079 struct files_struct
*files
= current
->files
;
1080 struct mm_struct
*mm
= current
->mm
;
1083 kthread_unuse_mm(mm
);
1088 struct nsproxy
*nsproxy
= current
->nsproxy
;
1091 current
->files
= NULL
;
1092 current
->nsproxy
= NULL
;
1093 task_unlock(current
);
1094 put_files_struct(files
);
1095 put_nsproxy(nsproxy
);
1099 static int __io_sq_thread_acquire_files(struct io_ring_ctx
*ctx
)
1101 if (!current
->files
) {
1102 struct files_struct
*files
;
1103 struct nsproxy
*nsproxy
;
1105 task_lock(ctx
->sqo_task
);
1106 files
= ctx
->sqo_task
->files
;
1108 task_unlock(ctx
->sqo_task
);
1111 atomic_inc(&files
->count
);
1112 get_nsproxy(ctx
->sqo_task
->nsproxy
);
1113 nsproxy
= ctx
->sqo_task
->nsproxy
;
1114 task_unlock(ctx
->sqo_task
);
1117 current
->files
= files
;
1118 current
->nsproxy
= nsproxy
;
1119 task_unlock(current
);
1124 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
1126 struct mm_struct
*mm
;
1131 /* Should never happen */
1132 if (unlikely(!(ctx
->flags
& IORING_SETUP_SQPOLL
)))
1135 task_lock(ctx
->sqo_task
);
1136 mm
= ctx
->sqo_task
->mm
;
1137 if (unlikely(!mm
|| !mmget_not_zero(mm
)))
1139 task_unlock(ctx
->sqo_task
);
1149 static int io_sq_thread_acquire_mm_files(struct io_ring_ctx
*ctx
,
1150 struct io_kiocb
*req
)
1152 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1155 if (def
->work_flags
& IO_WQ_WORK_MM
) {
1156 ret
= __io_sq_thread_acquire_mm(ctx
);
1161 if (def
->needs_file
|| (def
->work_flags
& IO_WQ_WORK_FILES
)) {
1162 ret
= __io_sq_thread_acquire_files(ctx
);
1170 static void io_sq_thread_associate_blkcg(struct io_ring_ctx
*ctx
,
1171 struct cgroup_subsys_state
**cur_css
)
1174 #ifdef CONFIG_BLK_CGROUP
1175 /* puts the old one when swapping */
1176 if (*cur_css
!= ctx
->sqo_blkcg_css
) {
1177 kthread_associate_blkcg(ctx
->sqo_blkcg_css
);
1178 *cur_css
= ctx
->sqo_blkcg_css
;
1183 static void io_sq_thread_unassociate_blkcg(void)
1185 #ifdef CONFIG_BLK_CGROUP
1186 kthread_associate_blkcg(NULL
);
1190 static inline void req_set_fail_links(struct io_kiocb
*req
)
1192 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1193 req
->flags
|= REQ_F_FAIL_LINK
;
1197 * None of these are dereferenced, they are simply used to check if any of
1198 * them have changed. If we're under current and check they are still the
1199 * same, we're fine to grab references to them for actual out-of-line use.
1201 static void io_init_identity(struct io_identity
*id
)
1203 id
->files
= current
->files
;
1204 id
->mm
= current
->mm
;
1205 #ifdef CONFIG_BLK_CGROUP
1207 id
->blkcg_css
= blkcg_css();
1210 id
->creds
= current_cred();
1211 id
->nsproxy
= current
->nsproxy
;
1212 id
->fs
= current
->fs
;
1213 id
->fsize
= rlimit(RLIMIT_FSIZE
);
1215 id
->loginuid
= current
->loginuid
;
1216 id
->sessionid
= current
->sessionid
;
1218 refcount_set(&id
->count
, 1);
1221 static inline void __io_req_init_async(struct io_kiocb
*req
)
1223 memset(&req
->work
, 0, sizeof(req
->work
));
1224 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1228 * Note: must call io_req_init_async() for the first time you
1229 * touch any members of io_wq_work.
1231 static inline void io_req_init_async(struct io_kiocb
*req
)
1233 struct io_uring_task
*tctx
= current
->io_uring
;
1235 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1238 __io_req_init_async(req
);
1240 /* Grab a ref if this isn't our static identity */
1241 req
->work
.identity
= tctx
->identity
;
1242 if (tctx
->identity
!= &tctx
->__identity
)
1243 refcount_inc(&req
->work
.identity
->count
);
1246 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
1248 return ctx
->flags
& IORING_SETUP_SQPOLL
;
1251 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1253 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1255 complete(&ctx
->ref_comp
);
1258 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1260 return !req
->timeout
.off
;
1263 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1265 struct io_ring_ctx
*ctx
;
1268 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1272 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
1273 if (!ctx
->fallback_req
)
1277 * Use 5 bits less than the max cq entries, that should give us around
1278 * 32 entries per hash list if totally full and uniformly spread.
1280 hash_bits
= ilog2(p
->cq_entries
);
1284 ctx
->cancel_hash_bits
= hash_bits
;
1285 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1287 if (!ctx
->cancel_hash
)
1289 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1291 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1292 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1295 ctx
->flags
= p
->flags
;
1296 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1297 INIT_LIST_HEAD(&ctx
->sqd_list
);
1298 init_waitqueue_head(&ctx
->cq_wait
);
1299 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1300 init_completion(&ctx
->ref_comp
);
1301 init_completion(&ctx
->sq_thread_comp
);
1302 idr_init(&ctx
->io_buffer_idr
);
1303 idr_init(&ctx
->personality_idr
);
1304 mutex_init(&ctx
->uring_lock
);
1305 init_waitqueue_head(&ctx
->wait
);
1306 spin_lock_init(&ctx
->completion_lock
);
1307 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1308 INIT_LIST_HEAD(&ctx
->defer_list
);
1309 INIT_LIST_HEAD(&ctx
->timeout_list
);
1310 spin_lock_init(&ctx
->inflight_lock
);
1311 INIT_LIST_HEAD(&ctx
->inflight_list
);
1312 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
1313 init_llist_head(&ctx
->file_put_llist
);
1316 if (ctx
->fallback_req
)
1317 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
1318 kfree(ctx
->cancel_hash
);
1323 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1325 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1326 struct io_ring_ctx
*ctx
= req
->ctx
;
1328 return seq
!= ctx
->cached_cq_tail
1329 + READ_ONCE(ctx
->cached_cq_overflow
);
1335 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1337 struct io_rings
*rings
= ctx
->rings
;
1339 /* order cqe stores with ring update */
1340 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1342 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1343 wake_up_interruptible(&ctx
->cq_wait
);
1344 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1348 static void io_put_identity(struct io_uring_task
*tctx
, struct io_kiocb
*req
)
1350 if (req
->work
.identity
== &tctx
->__identity
)
1352 if (refcount_dec_and_test(&req
->work
.identity
->count
))
1353 kfree(req
->work
.identity
);
1356 static void io_req_clean_work(struct io_kiocb
*req
)
1358 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1361 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1363 if (req
->work
.flags
& IO_WQ_WORK_MM
) {
1364 mmdrop(req
->work
.identity
->mm
);
1365 req
->work
.flags
&= ~IO_WQ_WORK_MM
;
1367 #ifdef CONFIG_BLK_CGROUP
1368 if (req
->work
.flags
& IO_WQ_WORK_BLKCG
) {
1369 css_put(req
->work
.identity
->blkcg_css
);
1370 req
->work
.flags
&= ~IO_WQ_WORK_BLKCG
;
1373 if (req
->work
.flags
& IO_WQ_WORK_CREDS
) {
1374 put_cred(req
->work
.identity
->creds
);
1375 req
->work
.flags
&= ~IO_WQ_WORK_CREDS
;
1377 if (req
->work
.flags
& IO_WQ_WORK_FS
) {
1378 struct fs_struct
*fs
= req
->work
.identity
->fs
;
1380 spin_lock(&req
->work
.identity
->fs
->lock
);
1383 spin_unlock(&req
->work
.identity
->fs
->lock
);
1386 req
->work
.flags
&= ~IO_WQ_WORK_FS
;
1389 io_put_identity(req
->task
->io_uring
, req
);
1393 * Create a private copy of io_identity, since some fields don't match
1394 * the current context.
1396 static bool io_identity_cow(struct io_kiocb
*req
)
1398 struct io_uring_task
*tctx
= current
->io_uring
;
1399 const struct cred
*creds
= NULL
;
1400 struct io_identity
*id
;
1402 if (req
->work
.flags
& IO_WQ_WORK_CREDS
)
1403 creds
= req
->work
.identity
->creds
;
1405 id
= kmemdup(req
->work
.identity
, sizeof(*id
), GFP_KERNEL
);
1406 if (unlikely(!id
)) {
1407 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1412 * We can safely just re-init the creds we copied Either the field
1413 * matches the current one, or we haven't grabbed it yet. The only
1414 * exception is ->creds, through registered personalities, so handle
1415 * that one separately.
1417 io_init_identity(id
);
1421 /* add one for this request */
1422 refcount_inc(&id
->count
);
1424 /* drop tctx and req identity references, if needed */
1425 if (tctx
->identity
!= &tctx
->__identity
&&
1426 refcount_dec_and_test(&tctx
->identity
->count
))
1427 kfree(tctx
->identity
);
1428 if (req
->work
.identity
!= &tctx
->__identity
&&
1429 refcount_dec_and_test(&req
->work
.identity
->count
))
1430 kfree(req
->work
.identity
);
1432 req
->work
.identity
= id
;
1433 tctx
->identity
= id
;
1437 static bool io_grab_identity(struct io_kiocb
*req
)
1439 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1440 struct io_identity
*id
= req
->work
.identity
;
1441 struct io_ring_ctx
*ctx
= req
->ctx
;
1443 if (def
->work_flags
& IO_WQ_WORK_FSIZE
) {
1444 if (id
->fsize
!= rlimit(RLIMIT_FSIZE
))
1446 req
->work
.flags
|= IO_WQ_WORK_FSIZE
;
1448 #ifdef CONFIG_BLK_CGROUP
1449 if (!(req
->work
.flags
& IO_WQ_WORK_BLKCG
) &&
1450 (def
->work_flags
& IO_WQ_WORK_BLKCG
)) {
1452 if (id
->blkcg_css
!= blkcg_css()) {
1457 * This should be rare, either the cgroup is dying or the task
1458 * is moving cgroups. Just punt to root for the handful of ios.
1460 if (css_tryget_online(id
->blkcg_css
))
1461 req
->work
.flags
|= IO_WQ_WORK_BLKCG
;
1465 if (!(req
->work
.flags
& IO_WQ_WORK_CREDS
)) {
1466 if (id
->creds
!= current_cred())
1468 get_cred(id
->creds
);
1469 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
1472 if (!uid_eq(current
->loginuid
, id
->loginuid
) ||
1473 current
->sessionid
!= id
->sessionid
)
1476 if (!(req
->work
.flags
& IO_WQ_WORK_FS
) &&
1477 (def
->work_flags
& IO_WQ_WORK_FS
)) {
1478 if (current
->fs
!= id
->fs
)
1480 spin_lock(&id
->fs
->lock
);
1481 if (!id
->fs
->in_exec
) {
1483 req
->work
.flags
|= IO_WQ_WORK_FS
;
1485 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1487 spin_unlock(¤t
->fs
->lock
);
1489 if (!(req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1490 (def
->work_flags
& IO_WQ_WORK_FILES
) &&
1491 !(req
->flags
& REQ_F_NO_FILE_TABLE
)) {
1492 if (id
->files
!= current
->files
||
1493 id
->nsproxy
!= current
->nsproxy
)
1495 atomic_inc(&id
->files
->count
);
1496 get_nsproxy(id
->nsproxy
);
1497 req
->flags
|= REQ_F_INFLIGHT
;
1499 spin_lock_irq(&ctx
->inflight_lock
);
1500 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
1501 spin_unlock_irq(&ctx
->inflight_lock
);
1502 req
->work
.flags
|= IO_WQ_WORK_FILES
;
1508 static void io_prep_async_work(struct io_kiocb
*req
)
1510 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1511 struct io_ring_ctx
*ctx
= req
->ctx
;
1512 struct io_identity
*id
;
1514 io_req_init_async(req
);
1515 id
= req
->work
.identity
;
1517 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1518 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1520 if (req
->flags
& REQ_F_ISREG
) {
1521 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1522 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1524 if (def
->unbound_nonreg_file
)
1525 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1528 /* ->mm can never change on us */
1529 if (!(req
->work
.flags
& IO_WQ_WORK_MM
) &&
1530 (def
->work_flags
& IO_WQ_WORK_MM
)) {
1532 req
->work
.flags
|= IO_WQ_WORK_MM
;
1535 /* if we fail grabbing identity, we must COW, regrab, and retry */
1536 if (io_grab_identity(req
))
1539 if (!io_identity_cow(req
))
1542 /* can't fail at this point */
1543 if (!io_grab_identity(req
))
1547 static void io_prep_async_link(struct io_kiocb
*req
)
1549 struct io_kiocb
*cur
;
1551 io_for_each_link(cur
, req
)
1552 io_prep_async_work(cur
);
1555 static struct io_kiocb
*__io_queue_async_work(struct io_kiocb
*req
)
1557 struct io_ring_ctx
*ctx
= req
->ctx
;
1558 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1560 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1561 &req
->work
, req
->flags
);
1562 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1566 static void io_queue_async_work(struct io_kiocb
*req
)
1568 struct io_kiocb
*link
;
1570 /* init ->work of the whole link before punting */
1571 io_prep_async_link(req
);
1572 link
= __io_queue_async_work(req
);
1575 io_queue_linked_timeout(link
);
1578 static void io_kill_timeout(struct io_kiocb
*req
)
1580 struct io_timeout_data
*io
= req
->async_data
;
1583 ret
= hrtimer_try_to_cancel(&io
->timer
);
1585 atomic_set(&req
->ctx
->cq_timeouts
,
1586 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1587 list_del_init(&req
->timeout
.list
);
1588 io_cqring_fill_event(req
, 0);
1589 io_put_req_deferred(req
, 1);
1594 * Returns true if we found and killed one or more timeouts
1596 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
1597 struct files_struct
*files
)
1599 struct io_kiocb
*req
, *tmp
;
1602 spin_lock_irq(&ctx
->completion_lock
);
1603 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
1604 if (io_match_task(req
, tsk
, files
)) {
1605 io_kill_timeout(req
);
1609 spin_unlock_irq(&ctx
->completion_lock
);
1610 return canceled
!= 0;
1613 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1616 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1617 struct io_defer_entry
, list
);
1618 struct io_kiocb
*link
;
1620 if (req_need_defer(de
->req
, de
->seq
))
1622 list_del_init(&de
->list
);
1623 /* punt-init is done before queueing for defer */
1624 link
= __io_queue_async_work(de
->req
);
1626 __io_queue_linked_timeout(link
);
1627 /* drop submission reference */
1628 io_put_req_deferred(link
, 1);
1631 } while (!list_empty(&ctx
->defer_list
));
1634 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1636 while (!list_empty(&ctx
->timeout_list
)) {
1637 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1638 struct io_kiocb
, timeout
.list
);
1640 if (io_is_timeout_noseq(req
))
1642 if (req
->timeout
.target_seq
!= ctx
->cached_cq_tail
1643 - atomic_read(&ctx
->cq_timeouts
))
1646 list_del_init(&req
->timeout
.list
);
1647 io_kill_timeout(req
);
1651 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1653 io_flush_timeouts(ctx
);
1654 __io_commit_cqring(ctx
);
1656 if (unlikely(!list_empty(&ctx
->defer_list
)))
1657 __io_queue_deferred(ctx
);
1660 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1662 struct io_rings
*r
= ctx
->rings
;
1664 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1667 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1669 struct io_rings
*rings
= ctx
->rings
;
1672 tail
= ctx
->cached_cq_tail
;
1674 * writes to the cq entry need to come after reading head; the
1675 * control dependency is enough as we're using WRITE_ONCE to
1678 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1681 ctx
->cached_cq_tail
++;
1682 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1685 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1689 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1691 if (!ctx
->eventfd_async
)
1693 return io_wq_current_is_worker();
1696 static inline unsigned __io_cqring_events(struct io_ring_ctx
*ctx
)
1698 return ctx
->cached_cq_tail
- READ_ONCE(ctx
->rings
->cq
.head
);
1701 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1703 if (waitqueue_active(&ctx
->wait
))
1704 wake_up(&ctx
->wait
);
1705 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1706 wake_up(&ctx
->sq_data
->wait
);
1707 if (io_should_trigger_evfd(ctx
))
1708 eventfd_signal(ctx
->cq_ev_fd
, 1);
1711 /* Returns true if there are no backlogged entries after the flush */
1712 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1713 struct task_struct
*tsk
,
1714 struct files_struct
*files
)
1716 struct io_rings
*rings
= ctx
->rings
;
1717 struct io_kiocb
*req
, *tmp
;
1718 struct io_uring_cqe
*cqe
;
1719 unsigned long flags
;
1723 if (!force
&& __io_cqring_events(ctx
) == rings
->cq_ring_entries
)
1726 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1727 list_for_each_entry_safe(req
, tmp
, &ctx
->cq_overflow_list
, compl.list
) {
1728 if (!io_match_task(req
, tsk
, files
))
1731 cqe
= io_get_cqring(ctx
);
1735 list_move(&req
->compl.list
, &list
);
1737 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1738 WRITE_ONCE(cqe
->res
, req
->result
);
1739 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1741 ctx
->cached_cq_overflow
++;
1742 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1743 ctx
->cached_cq_overflow
);
1747 all_flushed
= list_empty(&ctx
->cq_overflow_list
);
1749 clear_bit(0, &ctx
->sq_check_overflow
);
1750 clear_bit(0, &ctx
->cq_check_overflow
);
1751 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1754 io_commit_cqring(ctx
);
1755 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1756 io_cqring_ev_posted(ctx
);
1758 while (!list_empty(&list
)) {
1759 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1760 list_del(&req
->compl.list
);
1767 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1769 struct io_ring_ctx
*ctx
= req
->ctx
;
1770 struct io_uring_cqe
*cqe
;
1772 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1775 * If we can't get a cq entry, userspace overflowed the
1776 * submission (by quite a lot). Increment the overflow count in
1779 cqe
= io_get_cqring(ctx
);
1781 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1782 WRITE_ONCE(cqe
->res
, res
);
1783 WRITE_ONCE(cqe
->flags
, cflags
);
1784 } else if (ctx
->cq_overflow_flushed
||
1785 atomic_read(&req
->task
->io_uring
->in_idle
)) {
1787 * If we're in ring overflow flush mode, or in task cancel mode,
1788 * then we cannot store the request for later flushing, we need
1789 * to drop it on the floor.
1791 ctx
->cached_cq_overflow
++;
1792 WRITE_ONCE(ctx
->rings
->cq_overflow
, ctx
->cached_cq_overflow
);
1794 if (list_empty(&ctx
->cq_overflow_list
)) {
1795 set_bit(0, &ctx
->sq_check_overflow
);
1796 set_bit(0, &ctx
->cq_check_overflow
);
1797 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1801 req
->compl.cflags
= cflags
;
1802 refcount_inc(&req
->refs
);
1803 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1807 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1809 __io_cqring_fill_event(req
, res
, 0);
1812 static void io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1814 struct io_ring_ctx
*ctx
= req
->ctx
;
1815 unsigned long flags
;
1817 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1818 __io_cqring_fill_event(req
, res
, cflags
);
1819 io_commit_cqring(ctx
);
1820 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1822 io_cqring_ev_posted(ctx
);
1825 static void io_submit_flush_completions(struct io_comp_state
*cs
)
1827 struct io_ring_ctx
*ctx
= cs
->ctx
;
1829 spin_lock_irq(&ctx
->completion_lock
);
1830 while (!list_empty(&cs
->list
)) {
1831 struct io_kiocb
*req
;
1833 req
= list_first_entry(&cs
->list
, struct io_kiocb
, compl.list
);
1834 list_del(&req
->compl.list
);
1835 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
1838 * io_free_req() doesn't care about completion_lock unless one
1839 * of these flags is set. REQ_F_WORK_INITIALIZED is in the list
1840 * because of a potential deadlock with req->work.fs->lock
1842 if (req
->flags
& (REQ_F_FAIL_LINK
|REQ_F_LINK_TIMEOUT
1843 |REQ_F_WORK_INITIALIZED
)) {
1844 spin_unlock_irq(&ctx
->completion_lock
);
1846 spin_lock_irq(&ctx
->completion_lock
);
1851 io_commit_cqring(ctx
);
1852 spin_unlock_irq(&ctx
->completion_lock
);
1854 io_cqring_ev_posted(ctx
);
1858 static void __io_req_complete(struct io_kiocb
*req
, long res
, unsigned cflags
,
1859 struct io_comp_state
*cs
)
1862 io_cqring_add_event(req
, res
, cflags
);
1867 req
->compl.cflags
= cflags
;
1868 list_add_tail(&req
->compl.list
, &cs
->list
);
1870 io_submit_flush_completions(cs
);
1874 static void io_req_complete(struct io_kiocb
*req
, long res
)
1876 __io_req_complete(req
, res
, 0, NULL
);
1879 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1881 return req
== (struct io_kiocb
*)
1882 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1885 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1887 struct io_kiocb
*req
;
1889 req
= ctx
->fallback_req
;
1890 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1896 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1897 struct io_submit_state
*state
)
1899 if (!state
->free_reqs
) {
1900 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1904 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1905 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1908 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1909 * retry single alloc to be on the safe side.
1911 if (unlikely(ret
<= 0)) {
1912 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1913 if (!state
->reqs
[0])
1917 state
->free_reqs
= ret
;
1921 return state
->reqs
[state
->free_reqs
];
1923 return io_get_fallback_req(ctx
);
1926 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1933 static void io_dismantle_req(struct io_kiocb
*req
)
1937 if (req
->async_data
)
1938 kfree(req
->async_data
);
1940 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1941 if (req
->fixed_file_refs
)
1942 percpu_ref_put(req
->fixed_file_refs
);
1943 io_req_clean_work(req
);
1946 static void __io_free_req(struct io_kiocb
*req
)
1948 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1949 struct io_ring_ctx
*ctx
= req
->ctx
;
1951 io_dismantle_req(req
);
1953 percpu_counter_dec(&tctx
->inflight
);
1954 if (atomic_read(&tctx
->in_idle
))
1955 wake_up(&tctx
->wait
);
1956 put_task_struct(req
->task
);
1958 if (likely(!io_is_fallback_req(req
)))
1959 kmem_cache_free(req_cachep
, req
);
1961 clear_bit_unlock(0, (unsigned long *) &ctx
->fallback_req
);
1962 percpu_ref_put(&ctx
->refs
);
1965 static inline void io_remove_next_linked(struct io_kiocb
*req
)
1967 struct io_kiocb
*nxt
= req
->link
;
1969 req
->link
= nxt
->link
;
1973 static void io_kill_linked_timeout(struct io_kiocb
*req
)
1975 struct io_ring_ctx
*ctx
= req
->ctx
;
1976 struct io_kiocb
*link
;
1977 bool cancelled
= false;
1978 unsigned long flags
;
1980 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1984 * Can happen if a linked timeout fired and link had been like
1985 * req -> link t-out -> link t-out [-> ...]
1987 if (link
&& (link
->flags
& REQ_F_LTIMEOUT_ACTIVE
)) {
1988 struct io_timeout_data
*io
= link
->async_data
;
1991 io_remove_next_linked(req
);
1992 link
->timeout
.head
= NULL
;
1993 ret
= hrtimer_try_to_cancel(&io
->timer
);
1995 io_cqring_fill_event(link
, -ECANCELED
);
1996 io_commit_cqring(ctx
);
2000 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
2001 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
2004 io_cqring_ev_posted(ctx
);
2010 static void io_fail_links(struct io_kiocb
*req
)
2012 struct io_kiocb
*link
, *nxt
;
2013 struct io_ring_ctx
*ctx
= req
->ctx
;
2014 unsigned long flags
;
2016 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
2024 trace_io_uring_fail_link(req
, link
);
2025 io_cqring_fill_event(link
, -ECANCELED
);
2028 * It's ok to free under spinlock as they're not linked anymore,
2029 * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
2032 if (link
->flags
& REQ_F_WORK_INITIALIZED
)
2033 io_put_req_deferred(link
, 2);
2035 io_double_put_req(link
);
2038 io_commit_cqring(ctx
);
2039 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
2041 io_cqring_ev_posted(ctx
);
2044 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
2046 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
2047 io_kill_linked_timeout(req
);
2050 * If LINK is set, we have dependent requests in this chain. If we
2051 * didn't fail this request, queue the first one up, moving any other
2052 * dependencies to the next request. In case of failure, fail the rest
2055 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
))) {
2056 struct io_kiocb
*nxt
= req
->link
;
2065 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
2067 if (likely(!(req
->link
) && !(req
->flags
& REQ_F_LINK_TIMEOUT
)))
2069 return __io_req_find_next(req
);
2072 static int io_req_task_work_add(struct io_kiocb
*req
)
2074 struct task_struct
*tsk
= req
->task
;
2075 struct io_ring_ctx
*ctx
= req
->ctx
;
2076 enum task_work_notify_mode notify
;
2079 if (tsk
->flags
& PF_EXITING
)
2083 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2084 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2085 * processing task_work. There's no reliable way to tell if TWA_RESUME
2089 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
))
2090 notify
= TWA_SIGNAL
;
2092 ret
= task_work_add(tsk
, &req
->task_work
, notify
);
2094 wake_up_process(tsk
);
2099 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
2101 struct io_ring_ctx
*ctx
= req
->ctx
;
2103 spin_lock_irq(&ctx
->completion_lock
);
2104 io_cqring_fill_event(req
, error
);
2105 io_commit_cqring(ctx
);
2106 spin_unlock_irq(&ctx
->completion_lock
);
2108 io_cqring_ev_posted(ctx
);
2109 req_set_fail_links(req
);
2110 io_double_put_req(req
);
2113 static void io_req_task_cancel(struct callback_head
*cb
)
2115 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2116 struct io_ring_ctx
*ctx
= req
->ctx
;
2118 __io_req_task_cancel(req
, -ECANCELED
);
2119 percpu_ref_put(&ctx
->refs
);
2122 static void __io_req_task_submit(struct io_kiocb
*req
)
2124 struct io_ring_ctx
*ctx
= req
->ctx
;
2126 if (!__io_sq_thread_acquire_mm(ctx
) &&
2127 !__io_sq_thread_acquire_files(ctx
)) {
2128 mutex_lock(&ctx
->uring_lock
);
2129 __io_queue_sqe(req
, NULL
);
2130 mutex_unlock(&ctx
->uring_lock
);
2132 __io_req_task_cancel(req
, -EFAULT
);
2136 static void io_req_task_submit(struct callback_head
*cb
)
2138 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2139 struct io_ring_ctx
*ctx
= req
->ctx
;
2141 __io_req_task_submit(req
);
2142 percpu_ref_put(&ctx
->refs
);
2145 static void io_req_task_queue(struct io_kiocb
*req
)
2149 init_task_work(&req
->task_work
, io_req_task_submit
);
2150 percpu_ref_get(&req
->ctx
->refs
);
2152 ret
= io_req_task_work_add(req
);
2153 if (unlikely(ret
)) {
2154 struct task_struct
*tsk
;
2156 init_task_work(&req
->task_work
, io_req_task_cancel
);
2157 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2158 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2159 wake_up_process(tsk
);
2163 static inline void io_queue_next(struct io_kiocb
*req
)
2165 struct io_kiocb
*nxt
= io_req_find_next(req
);
2168 io_req_task_queue(nxt
);
2171 static void io_free_req(struct io_kiocb
*req
)
2178 void *reqs
[IO_IOPOLL_BATCH
];
2181 struct task_struct
*task
;
2185 static inline void io_init_req_batch(struct req_batch
*rb
)
2192 static void __io_req_free_batch_flush(struct io_ring_ctx
*ctx
,
2193 struct req_batch
*rb
)
2195 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
2196 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
2200 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2201 struct req_batch
*rb
)
2204 __io_req_free_batch_flush(ctx
, rb
);
2206 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2208 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2209 put_task_struct_many(rb
->task
, rb
->task_refs
);
2214 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
)
2216 if (unlikely(io_is_fallback_req(req
))) {
2222 if (req
->task
!= rb
->task
) {
2224 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2226 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2227 put_task_struct_many(rb
->task
, rb
->task_refs
);
2229 rb
->task
= req
->task
;
2234 io_dismantle_req(req
);
2235 rb
->reqs
[rb
->to_free
++] = req
;
2236 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
2237 __io_req_free_batch_flush(req
->ctx
, rb
);
2241 * Drop reference to request, return next in chain (if there is one) if this
2242 * was the last reference to this request.
2244 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2246 struct io_kiocb
*nxt
= NULL
;
2248 if (refcount_dec_and_test(&req
->refs
)) {
2249 nxt
= io_req_find_next(req
);
2255 static void io_put_req(struct io_kiocb
*req
)
2257 if (refcount_dec_and_test(&req
->refs
))
2261 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2263 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2268 static void io_free_req_deferred(struct io_kiocb
*req
)
2272 init_task_work(&req
->task_work
, io_put_req_deferred_cb
);
2273 ret
= io_req_task_work_add(req
);
2274 if (unlikely(ret
)) {
2275 struct task_struct
*tsk
;
2277 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2278 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2279 wake_up_process(tsk
);
2283 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2285 if (refcount_sub_and_test(refs
, &req
->refs
))
2286 io_free_req_deferred(req
);
2289 static struct io_wq_work
*io_steal_work(struct io_kiocb
*req
)
2291 struct io_kiocb
*nxt
;
2294 * A ref is owned by io-wq in which context we're. So, if that's the
2295 * last one, it's safe to steal next work. False negatives are Ok,
2296 * it just will be re-punted async in io_put_work()
2298 if (refcount_read(&req
->refs
) != 1)
2301 nxt
= io_req_find_next(req
);
2302 return nxt
? &nxt
->work
: NULL
;
2305 static void io_double_put_req(struct io_kiocb
*req
)
2307 /* drop both submit and complete references */
2308 if (refcount_sub_and_test(2, &req
->refs
))
2312 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
2314 if (test_bit(0, &ctx
->cq_check_overflow
)) {
2316 * noflush == true is from the waitqueue handler, just ensure
2317 * we wake up the task, and the next invocation will flush the
2318 * entries. We cannot safely to it from here.
2323 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
2326 /* See comment at the top of this file */
2328 return __io_cqring_events(ctx
);
2331 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2333 struct io_rings
*rings
= ctx
->rings
;
2335 /* make sure SQ entry isn't read before tail */
2336 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2339 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2341 unsigned int cflags
;
2343 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2344 cflags
|= IORING_CQE_F_BUFFER
;
2345 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2350 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2352 struct io_buffer
*kbuf
;
2354 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2355 return io_put_kbuf(req
, kbuf
);
2358 static inline bool io_run_task_work(void)
2361 * Not safe to run on exiting task, and the task_work handling will
2362 * not add work to such a task.
2364 if (unlikely(current
->flags
& PF_EXITING
))
2366 if (current
->task_works
) {
2367 __set_current_state(TASK_RUNNING
);
2375 static void io_iopoll_queue(struct list_head
*again
)
2377 struct io_kiocb
*req
;
2380 req
= list_first_entry(again
, struct io_kiocb
, inflight_entry
);
2381 list_del(&req
->inflight_entry
);
2382 __io_complete_rw(req
, -EAGAIN
, 0, NULL
);
2383 } while (!list_empty(again
));
2387 * Find and free completed poll iocbs
2389 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2390 struct list_head
*done
)
2392 struct req_batch rb
;
2393 struct io_kiocb
*req
;
2396 /* order with ->result store in io_complete_rw_iopoll() */
2399 io_init_req_batch(&rb
);
2400 while (!list_empty(done
)) {
2403 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2404 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2406 req
->iopoll_completed
= 0;
2407 list_move_tail(&req
->inflight_entry
, &again
);
2410 list_del(&req
->inflight_entry
);
2412 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2413 cflags
= io_put_rw_kbuf(req
);
2415 __io_cqring_fill_event(req
, req
->result
, cflags
);
2418 if (refcount_dec_and_test(&req
->refs
))
2419 io_req_free_batch(&rb
, req
);
2422 io_commit_cqring(ctx
);
2423 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
2424 io_cqring_ev_posted(ctx
);
2425 io_req_free_batch_finish(ctx
, &rb
);
2427 if (!list_empty(&again
))
2428 io_iopoll_queue(&again
);
2431 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2434 struct io_kiocb
*req
, *tmp
;
2440 * Only spin for completions if we don't have multiple devices hanging
2441 * off our complete list, and we're under the requested amount.
2443 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2446 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2447 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2450 * Move completed and retryable entries to our local lists.
2451 * If we find a request that requires polling, break out
2452 * and complete those lists first, if we have entries there.
2454 if (READ_ONCE(req
->iopoll_completed
)) {
2455 list_move_tail(&req
->inflight_entry
, &done
);
2458 if (!list_empty(&done
))
2461 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2465 /* iopoll may have completed current req */
2466 if (READ_ONCE(req
->iopoll_completed
))
2467 list_move_tail(&req
->inflight_entry
, &done
);
2474 if (!list_empty(&done
))
2475 io_iopoll_complete(ctx
, nr_events
, &done
);
2481 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2482 * non-spinning poll check - we'll still enter the driver poll loop, but only
2483 * as a non-spinning completion check.
2485 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2488 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2491 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2494 if (*nr_events
>= min
)
2502 * We can't just wait for polled events to come to us, we have to actively
2503 * find and complete them.
2505 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2507 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2510 mutex_lock(&ctx
->uring_lock
);
2511 while (!list_empty(&ctx
->iopoll_list
)) {
2512 unsigned int nr_events
= 0;
2514 io_do_iopoll(ctx
, &nr_events
, 0);
2516 /* let it sleep and repeat later if can't complete a request */
2520 * Ensure we allow local-to-the-cpu processing to take place,
2521 * in this case we need to ensure that we reap all events.
2522 * Also let task_work, etc. to progress by releasing the mutex
2524 if (need_resched()) {
2525 mutex_unlock(&ctx
->uring_lock
);
2527 mutex_lock(&ctx
->uring_lock
);
2530 mutex_unlock(&ctx
->uring_lock
);
2533 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2535 unsigned int nr_events
= 0;
2536 int iters
= 0, ret
= 0;
2539 * We disallow the app entering submit/complete with polling, but we
2540 * still need to lock the ring to prevent racing with polled issue
2541 * that got punted to a workqueue.
2543 mutex_lock(&ctx
->uring_lock
);
2546 * Don't enter poll loop if we already have events pending.
2547 * If we do, we can potentially be spinning for commands that
2548 * already triggered a CQE (eg in error).
2550 if (io_cqring_events(ctx
, false))
2554 * If a submit got punted to a workqueue, we can have the
2555 * application entering polling for a command before it gets
2556 * issued. That app will hold the uring_lock for the duration
2557 * of the poll right here, so we need to take a breather every
2558 * now and then to ensure that the issue has a chance to add
2559 * the poll to the issued list. Otherwise we can spin here
2560 * forever, while the workqueue is stuck trying to acquire the
2563 if (!(++iters
& 7)) {
2564 mutex_unlock(&ctx
->uring_lock
);
2566 mutex_lock(&ctx
->uring_lock
);
2569 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2573 } while (min
&& !nr_events
&& !need_resched());
2575 mutex_unlock(&ctx
->uring_lock
);
2579 static void kiocb_end_write(struct io_kiocb
*req
)
2582 * Tell lockdep we inherited freeze protection from submission
2585 if (req
->flags
& REQ_F_ISREG
) {
2586 struct inode
*inode
= file_inode(req
->file
);
2588 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2590 file_end_write(req
->file
);
2593 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
,
2594 struct io_comp_state
*cs
)
2596 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2599 if (kiocb
->ki_flags
& IOCB_WRITE
)
2600 kiocb_end_write(req
);
2602 if (res
!= req
->result
)
2603 req_set_fail_links(req
);
2604 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2605 cflags
= io_put_rw_kbuf(req
);
2606 __io_req_complete(req
, res
, cflags
, cs
);
2610 static bool io_resubmit_prep(struct io_kiocb
*req
, int error
)
2612 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2613 ssize_t ret
= -ECANCELED
;
2614 struct iov_iter iter
;
2622 switch (req
->opcode
) {
2623 case IORING_OP_READV
:
2624 case IORING_OP_READ_FIXED
:
2625 case IORING_OP_READ
:
2628 case IORING_OP_WRITEV
:
2629 case IORING_OP_WRITE_FIXED
:
2630 case IORING_OP_WRITE
:
2634 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2639 if (!req
->async_data
) {
2640 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2643 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, &iter
, false);
2651 req_set_fail_links(req
);
2656 static bool io_rw_reissue(struct io_kiocb
*req
, long res
)
2659 umode_t mode
= file_inode(req
->file
)->i_mode
;
2662 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2664 if ((res
!= -EAGAIN
&& res
!= -EOPNOTSUPP
) || io_wq_current_is_worker())
2667 ret
= io_sq_thread_acquire_mm_files(req
->ctx
, req
);
2669 if (io_resubmit_prep(req
, ret
)) {
2670 refcount_inc(&req
->refs
);
2671 io_queue_async_work(req
);
2679 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2680 struct io_comp_state
*cs
)
2682 if (!io_rw_reissue(req
, res
))
2683 io_complete_rw_common(&req
->rw
.kiocb
, res
, cs
);
2686 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2688 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2690 __io_complete_rw(req
, res
, res2
, NULL
);
2693 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2695 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2697 if (kiocb
->ki_flags
& IOCB_WRITE
)
2698 kiocb_end_write(req
);
2700 if (res
!= -EAGAIN
&& res
!= req
->result
)
2701 req_set_fail_links(req
);
2703 WRITE_ONCE(req
->result
, res
);
2704 /* order with io_poll_complete() checking ->result */
2706 WRITE_ONCE(req
->iopoll_completed
, 1);
2710 * After the iocb has been issued, it's safe to be found on the poll list.
2711 * Adding the kiocb to the list AFTER submission ensures that we don't
2712 * find it from a io_iopoll_getevents() thread before the issuer is done
2713 * accessing the kiocb cookie.
2715 static void io_iopoll_req_issued(struct io_kiocb
*req
, bool in_async
)
2717 struct io_ring_ctx
*ctx
= req
->ctx
;
2720 * Track whether we have multiple files in our lists. This will impact
2721 * how we do polling eventually, not spinning if we're on potentially
2722 * different devices.
2724 if (list_empty(&ctx
->iopoll_list
)) {
2725 ctx
->poll_multi_file
= false;
2726 } else if (!ctx
->poll_multi_file
) {
2727 struct io_kiocb
*list_req
;
2729 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2731 if (list_req
->file
!= req
->file
)
2732 ctx
->poll_multi_file
= true;
2736 * For fast devices, IO may have already completed. If it has, add
2737 * it to the front so we find it first.
2739 if (READ_ONCE(req
->iopoll_completed
))
2740 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2742 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2745 * If IORING_SETUP_SQPOLL is enabled, sqes are either handled in sq thread
2746 * task context or in io worker task context. If current task context is
2747 * sq thread, we don't need to check whether should wake up sq thread.
2749 if (in_async
&& (ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2750 wq_has_sleeper(&ctx
->sq_data
->wait
))
2751 wake_up(&ctx
->sq_data
->wait
);
2754 static inline void __io_state_file_put(struct io_submit_state
*state
)
2756 fput_many(state
->file
, state
->file_refs
);
2757 state
->file_refs
= 0;
2760 static inline void io_state_file_put(struct io_submit_state
*state
)
2762 if (state
->file_refs
)
2763 __io_state_file_put(state
);
2767 * Get as many references to a file as we have IOs left in this submission,
2768 * assuming most submissions are for one file, or at least that each file
2769 * has more than one submission.
2771 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2776 if (state
->file_refs
) {
2777 if (state
->fd
== fd
) {
2781 __io_state_file_put(state
);
2783 state
->file
= fget_many(fd
, state
->ios_left
);
2784 if (unlikely(!state
->file
))
2788 state
->file_refs
= state
->ios_left
- 1;
2792 static bool io_bdev_nowait(struct block_device
*bdev
)
2794 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2798 * If we tracked the file through the SCM inflight mechanism, we could support
2799 * any file. For now, just ensure that anything potentially problematic is done
2802 static bool io_file_supports_async(struct file
*file
, int rw
)
2804 umode_t mode
= file_inode(file
)->i_mode
;
2806 if (S_ISBLK(mode
)) {
2807 if (IS_ENABLED(CONFIG_BLOCK
) &&
2808 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2812 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2814 if (S_ISREG(mode
)) {
2815 if (IS_ENABLED(CONFIG_BLOCK
) &&
2816 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2817 file
->f_op
!= &io_uring_fops
)
2822 /* any ->read/write should understand O_NONBLOCK */
2823 if (file
->f_flags
& O_NONBLOCK
)
2826 if (!(file
->f_mode
& FMODE_NOWAIT
))
2830 return file
->f_op
->read_iter
!= NULL
;
2832 return file
->f_op
->write_iter
!= NULL
;
2835 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2837 struct io_ring_ctx
*ctx
= req
->ctx
;
2838 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2842 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2843 req
->flags
|= REQ_F_ISREG
;
2845 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2846 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2847 req
->flags
|= REQ_F_CUR_POS
;
2848 kiocb
->ki_pos
= req
->file
->f_pos
;
2850 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2851 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2852 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2856 ioprio
= READ_ONCE(sqe
->ioprio
);
2858 ret
= ioprio_check_cap(ioprio
);
2862 kiocb
->ki_ioprio
= ioprio
;
2864 kiocb
->ki_ioprio
= get_current_ioprio();
2866 /* don't allow async punt if RWF_NOWAIT was requested */
2867 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2868 req
->flags
|= REQ_F_NOWAIT
;
2870 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2871 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2872 !kiocb
->ki_filp
->f_op
->iopoll
)
2875 kiocb
->ki_flags
|= IOCB_HIPRI
;
2876 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2877 req
->iopoll_completed
= 0;
2879 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2881 kiocb
->ki_complete
= io_complete_rw
;
2884 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2885 req
->rw
.len
= READ_ONCE(sqe
->len
);
2886 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2890 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2896 case -ERESTARTNOINTR
:
2897 case -ERESTARTNOHAND
:
2898 case -ERESTART_RESTARTBLOCK
:
2900 * We can't just restart the syscall, since previously
2901 * submitted sqes may already be in progress. Just fail this
2907 kiocb
->ki_complete(kiocb
, ret
, 0);
2911 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2912 struct io_comp_state
*cs
)
2914 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2915 struct io_async_rw
*io
= req
->async_data
;
2917 /* add previously done IO, if any */
2918 if (io
&& io
->bytes_done
> 0) {
2920 ret
= io
->bytes_done
;
2922 ret
+= io
->bytes_done
;
2925 if (req
->flags
& REQ_F_CUR_POS
)
2926 req
->file
->f_pos
= kiocb
->ki_pos
;
2927 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2928 __io_complete_rw(req
, ret
, 0, cs
);
2930 io_rw_done(kiocb
, ret
);
2933 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2934 struct iov_iter
*iter
)
2936 struct io_ring_ctx
*ctx
= req
->ctx
;
2937 size_t len
= req
->rw
.len
;
2938 struct io_mapped_ubuf
*imu
;
2939 u16 index
, buf_index
= req
->buf_index
;
2943 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2945 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2946 imu
= &ctx
->user_bufs
[index
];
2947 buf_addr
= req
->rw
.addr
;
2950 if (buf_addr
+ len
< buf_addr
)
2952 /* not inside the mapped region */
2953 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2957 * May not be a start of buffer, set size appropriately
2958 * and advance us to the beginning.
2960 offset
= buf_addr
- imu
->ubuf
;
2961 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2965 * Don't use iov_iter_advance() here, as it's really slow for
2966 * using the latter parts of a big fixed buffer - it iterates
2967 * over each segment manually. We can cheat a bit here, because
2970 * 1) it's a BVEC iter, we set it up
2971 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2972 * first and last bvec
2974 * So just find our index, and adjust the iterator afterwards.
2975 * If the offset is within the first bvec (or the whole first
2976 * bvec, just use iov_iter_advance(). This makes it easier
2977 * since we can just skip the first segment, which may not
2978 * be PAGE_SIZE aligned.
2980 const struct bio_vec
*bvec
= imu
->bvec
;
2982 if (offset
<= bvec
->bv_len
) {
2983 iov_iter_advance(iter
, offset
);
2985 unsigned long seg_skip
;
2987 /* skip first vec */
2988 offset
-= bvec
->bv_len
;
2989 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2991 iter
->bvec
= bvec
+ seg_skip
;
2992 iter
->nr_segs
-= seg_skip
;
2993 iter
->count
-= bvec
->bv_len
+ offset
;
2994 iter
->iov_offset
= offset
& ~PAGE_MASK
;
3001 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3004 mutex_unlock(&ctx
->uring_lock
);
3007 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3010 * "Normal" inline submissions always hold the uring_lock, since we
3011 * grab it from the system call. Same is true for the SQPOLL offload.
3012 * The only exception is when we've detached the request and issue it
3013 * from an async worker thread, grab the lock for that case.
3016 mutex_lock(&ctx
->uring_lock
);
3019 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
3020 int bgid
, struct io_buffer
*kbuf
,
3023 struct io_buffer
*head
;
3025 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
3028 io_ring_submit_lock(req
->ctx
, needs_lock
);
3030 lockdep_assert_held(&req
->ctx
->uring_lock
);
3032 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
3034 if (!list_empty(&head
->list
)) {
3035 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
3037 list_del(&kbuf
->list
);
3040 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
3042 if (*len
> kbuf
->len
)
3045 kbuf
= ERR_PTR(-ENOBUFS
);
3048 io_ring_submit_unlock(req
->ctx
, needs_lock
);
3053 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
3056 struct io_buffer
*kbuf
;
3059 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3060 bgid
= req
->buf_index
;
3061 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
3064 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
3065 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3066 return u64_to_user_ptr(kbuf
->addr
);
3069 #ifdef CONFIG_COMPAT
3070 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
3073 struct compat_iovec __user
*uiov
;
3074 compat_ssize_t clen
;
3078 uiov
= u64_to_user_ptr(req
->rw
.addr
);
3079 if (!access_ok(uiov
, sizeof(*uiov
)))
3081 if (__get_user(clen
, &uiov
->iov_len
))
3087 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3089 return PTR_ERR(buf
);
3090 iov
[0].iov_base
= buf
;
3091 iov
[0].iov_len
= (compat_size_t
) len
;
3096 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3099 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
3103 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3106 len
= iov
[0].iov_len
;
3109 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3111 return PTR_ERR(buf
);
3112 iov
[0].iov_base
= buf
;
3113 iov
[0].iov_len
= len
;
3117 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3120 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3121 struct io_buffer
*kbuf
;
3123 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3124 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3125 iov
[0].iov_len
= kbuf
->len
;
3128 if (req
->rw
.len
!= 1)
3131 #ifdef CONFIG_COMPAT
3132 if (req
->ctx
->compat
)
3133 return io_compat_import(req
, iov
, needs_lock
);
3136 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3139 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
3140 struct iovec
**iovec
, struct iov_iter
*iter
,
3143 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3144 size_t sqe_len
= req
->rw
.len
;
3148 opcode
= req
->opcode
;
3149 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3151 return io_import_fixed(req
, rw
, iter
);
3154 /* buffer index only valid with fixed read/write, or buffer select */
3155 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3158 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3159 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3160 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3162 return PTR_ERR(buf
);
3163 req
->rw
.len
= sqe_len
;
3166 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3171 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3172 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3174 ret
= (*iovec
)->iov_len
;
3175 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
3181 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3185 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3187 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3191 * For files that don't have ->read_iter() and ->write_iter(), handle them
3192 * by looping over ->read() or ->write() manually.
3194 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3196 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3197 struct file
*file
= req
->file
;
3201 * Don't support polled IO through this interface, and we can't
3202 * support non-blocking either. For the latter, this just causes
3203 * the kiocb to be handled from an async context.
3205 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3207 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3210 while (iov_iter_count(iter
)) {
3214 if (!iov_iter_is_bvec(iter
)) {
3215 iovec
= iov_iter_iovec(iter
);
3217 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3218 iovec
.iov_len
= req
->rw
.len
;
3222 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3223 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3225 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3226 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3235 if (nr
!= iovec
.iov_len
)
3239 iov_iter_advance(iter
, nr
);
3245 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3246 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3248 struct io_async_rw
*rw
= req
->async_data
;
3250 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3251 rw
->free_iovec
= iovec
;
3253 /* can only be fixed buffers, no need to do anything */
3254 if (iov_iter_is_bvec(iter
))
3257 unsigned iov_off
= 0;
3259 rw
->iter
.iov
= rw
->fast_iov
;
3260 if (iter
->iov
!= fast_iov
) {
3261 iov_off
= iter
->iov
- fast_iov
;
3262 rw
->iter
.iov
+= iov_off
;
3264 if (rw
->fast_iov
!= fast_iov
)
3265 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3266 sizeof(struct iovec
) * iter
->nr_segs
);
3268 req
->flags
|= REQ_F_NEED_CLEANUP
;
3272 static inline int __io_alloc_async_data(struct io_kiocb
*req
)
3274 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3275 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3276 return req
->async_data
== NULL
;
3279 static int io_alloc_async_data(struct io_kiocb
*req
)
3281 if (!io_op_defs
[req
->opcode
].needs_async_data
)
3284 return __io_alloc_async_data(req
);
3287 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3288 const struct iovec
*fast_iov
,
3289 struct iov_iter
*iter
, bool force
)
3291 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_data
)
3293 if (!req
->async_data
) {
3294 if (__io_alloc_async_data(req
))
3297 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3302 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3304 struct io_async_rw
*iorw
= req
->async_data
;
3305 struct iovec
*iov
= iorw
->fast_iov
;
3308 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3309 if (unlikely(ret
< 0))
3312 iorw
->bytes_done
= 0;
3313 iorw
->free_iovec
= iov
;
3315 req
->flags
|= REQ_F_NEED_CLEANUP
;
3319 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3323 ret
= io_prep_rw(req
, sqe
);
3327 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3330 /* either don't need iovec imported or already have it */
3331 if (!req
->async_data
)
3333 return io_rw_prep_async(req
, READ
);
3337 * This is our waitqueue callback handler, registered through lock_page_async()
3338 * when we initially tried to do the IO with the iocb armed our waitqueue.
3339 * This gets called when the page is unlocked, and we generally expect that to
3340 * happen when the page IO is completed and the page is now uptodate. This will
3341 * queue a task_work based retry of the operation, attempting to copy the data
3342 * again. If the latter fails because the page was NOT uptodate, then we will
3343 * do a thread based blocking retry of the operation. That's the unexpected
3346 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3347 int sync
, void *arg
)
3349 struct wait_page_queue
*wpq
;
3350 struct io_kiocb
*req
= wait
->private;
3351 struct wait_page_key
*key
= arg
;
3354 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3356 if (!wake_page_match(wpq
, key
))
3359 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3360 list_del_init(&wait
->entry
);
3362 init_task_work(&req
->task_work
, io_req_task_submit
);
3363 percpu_ref_get(&req
->ctx
->refs
);
3365 /* submit ref gets dropped, acquire a new one */
3366 refcount_inc(&req
->refs
);
3367 ret
= io_req_task_work_add(req
);
3368 if (unlikely(ret
)) {
3369 struct task_struct
*tsk
;
3371 /* queue just for cancelation */
3372 init_task_work(&req
->task_work
, io_req_task_cancel
);
3373 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
3374 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
3375 wake_up_process(tsk
);
3381 * This controls whether a given IO request should be armed for async page
3382 * based retry. If we return false here, the request is handed to the async
3383 * worker threads for retry. If we're doing buffered reads on a regular file,
3384 * we prepare a private wait_page_queue entry and retry the operation. This
3385 * will either succeed because the page is now uptodate and unlocked, or it
3386 * will register a callback when the page is unlocked at IO completion. Through
3387 * that callback, io_uring uses task_work to setup a retry of the operation.
3388 * That retry will attempt the buffered read again. The retry will generally
3389 * succeed, or in rare cases where it fails, we then fall back to using the
3390 * async worker threads for a blocking retry.
3392 static bool io_rw_should_retry(struct io_kiocb
*req
)
3394 struct io_async_rw
*rw
= req
->async_data
;
3395 struct wait_page_queue
*wait
= &rw
->wpq
;
3396 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3398 /* never retry for NOWAIT, we just complete with -EAGAIN */
3399 if (req
->flags
& REQ_F_NOWAIT
)
3402 /* Only for buffered IO */
3403 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3407 * just use poll if we can, and don't attempt if the fs doesn't
3408 * support callback based unlocks
3410 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3413 wait
->wait
.func
= io_async_buf_func
;
3414 wait
->wait
.private = req
;
3415 wait
->wait
.flags
= 0;
3416 INIT_LIST_HEAD(&wait
->wait
.entry
);
3417 kiocb
->ki_flags
|= IOCB_WAITQ
;
3418 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3419 kiocb
->ki_waitq
= wait
;
3423 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3425 if (req
->file
->f_op
->read_iter
)
3426 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3427 else if (req
->file
->f_op
->read
)
3428 return loop_rw_iter(READ
, req
, iter
);
3433 static int io_read(struct io_kiocb
*req
, bool force_nonblock
,
3434 struct io_comp_state
*cs
)
3436 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3437 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3438 struct iov_iter __iter
, *iter
= &__iter
;
3439 struct io_async_rw
*rw
= req
->async_data
;
3440 ssize_t io_size
, ret
, ret2
;
3447 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3451 io_size
= iov_iter_count(iter
);
3452 req
->result
= io_size
;
3455 /* Ensure we clear previously set non-block flag */
3456 if (!force_nonblock
)
3457 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3459 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3462 /* If the file doesn't support async, just async punt */
3463 no_async
= force_nonblock
&& !io_file_supports_async(req
->file
, READ
);
3467 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3471 ret
= io_iter_do_read(req
, iter
);
3475 } else if (ret
== -EIOCBQUEUED
) {
3478 } else if (ret
== -EAGAIN
) {
3479 /* IOPOLL retry should happen for io-wq threads */
3480 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3482 /* no retry on NONBLOCK marked file */
3483 if (req
->file
->f_flags
& O_NONBLOCK
)
3485 /* some cases will consume bytes even on error returns */
3486 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3489 } else if (ret
< 0) {
3490 /* make sure -ERESTARTSYS -> -EINTR is done */
3494 /* read it all, or we did blocking attempt. no retry. */
3495 if (!iov_iter_count(iter
) || !force_nonblock
||
3496 (req
->file
->f_flags
& O_NONBLOCK
))
3501 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3508 rw
= req
->async_data
;
3509 /* it's copied and will be cleaned with ->io */
3511 /* now use our persistent iterator, if we aren't already */
3514 rw
->bytes_done
+= ret
;
3515 /* if we can retry, do so with the callbacks armed */
3516 if (!io_rw_should_retry(req
)) {
3517 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3522 * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
3523 * get -EIOCBQUEUED, then we'll get a notification when the desired
3524 * page gets unlocked. We can also get a partial read here, and if we
3525 * do, then just retry at the new offset.
3527 ret
= io_iter_do_read(req
, iter
);
3528 if (ret
== -EIOCBQUEUED
) {
3531 } else if (ret
> 0 && ret
< io_size
) {
3532 /* we got some bytes, but not all. retry. */
3536 kiocb_done(kiocb
, ret
, cs
);
3539 /* it's reportedly faster than delegating the null check to kfree() */
3545 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3549 ret
= io_prep_rw(req
, sqe
);
3553 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3556 /* either don't need iovec imported or already have it */
3557 if (!req
->async_data
)
3559 return io_rw_prep_async(req
, WRITE
);
3562 static int io_write(struct io_kiocb
*req
, bool force_nonblock
,
3563 struct io_comp_state
*cs
)
3565 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3566 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3567 struct iov_iter __iter
, *iter
= &__iter
;
3568 struct io_async_rw
*rw
= req
->async_data
;
3569 ssize_t ret
, ret2
, io_size
;
3575 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3579 io_size
= iov_iter_count(iter
);
3580 req
->result
= io_size
;
3582 /* Ensure we clear previously set non-block flag */
3583 if (!force_nonblock
)
3584 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3586 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3588 /* If the file doesn't support async, just async punt */
3589 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3592 /* file path doesn't support NOWAIT for non-direct_IO */
3593 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3594 (req
->flags
& REQ_F_ISREG
))
3597 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3602 * Open-code file_start_write here to grab freeze protection,
3603 * which will be released by another thread in
3604 * io_complete_rw(). Fool lockdep by telling it the lock got
3605 * released so that it doesn't complain about the held lock when
3606 * we return to userspace.
3608 if (req
->flags
& REQ_F_ISREG
) {
3609 sb_start_write(file_inode(req
->file
)->i_sb
);
3610 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3613 kiocb
->ki_flags
|= IOCB_WRITE
;
3615 if (req
->file
->f_op
->write_iter
)
3616 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3617 else if (req
->file
->f_op
->write
)
3618 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3623 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3624 * retry them without IOCB_NOWAIT.
3626 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3628 /* no retry on NONBLOCK marked file */
3629 if (ret2
== -EAGAIN
&& (req
->file
->f_flags
& O_NONBLOCK
))
3631 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3632 /* IOPOLL retry should happen for io-wq threads */
3633 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3636 kiocb_done(kiocb
, ret2
, cs
);
3639 /* some cases will consume bytes even on error returns */
3640 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3641 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3646 /* it's reportedly faster than delegating the null check to kfree() */
3652 static int io_renameat_prep(struct io_kiocb
*req
,
3653 const struct io_uring_sqe
*sqe
)
3655 struct io_rename
*ren
= &req
->rename
;
3656 const char __user
*oldf
, *newf
;
3658 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3661 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3662 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3663 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3664 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3665 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3667 ren
->oldpath
= getname(oldf
);
3668 if (IS_ERR(ren
->oldpath
))
3669 return PTR_ERR(ren
->oldpath
);
3671 ren
->newpath
= getname(newf
);
3672 if (IS_ERR(ren
->newpath
)) {
3673 putname(ren
->oldpath
);
3674 return PTR_ERR(ren
->newpath
);
3677 req
->flags
|= REQ_F_NEED_CLEANUP
;
3681 static int io_renameat(struct io_kiocb
*req
, bool force_nonblock
)
3683 struct io_rename
*ren
= &req
->rename
;
3689 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3690 ren
->newpath
, ren
->flags
);
3692 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3694 req_set_fail_links(req
);
3695 io_req_complete(req
, ret
);
3699 static int io_unlinkat_prep(struct io_kiocb
*req
,
3700 const struct io_uring_sqe
*sqe
)
3702 struct io_unlink
*un
= &req
->unlink
;
3703 const char __user
*fname
;
3705 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3708 un
->dfd
= READ_ONCE(sqe
->fd
);
3710 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3711 if (un
->flags
& ~AT_REMOVEDIR
)
3714 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3715 un
->filename
= getname(fname
);
3716 if (IS_ERR(un
->filename
))
3717 return PTR_ERR(un
->filename
);
3719 req
->flags
|= REQ_F_NEED_CLEANUP
;
3723 static int io_unlinkat(struct io_kiocb
*req
, bool force_nonblock
)
3725 struct io_unlink
*un
= &req
->unlink
;
3731 if (un
->flags
& AT_REMOVEDIR
)
3732 ret
= do_rmdir(un
->dfd
, un
->filename
);
3734 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3736 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3738 req_set_fail_links(req
);
3739 io_req_complete(req
, ret
);
3743 static int io_shutdown_prep(struct io_kiocb
*req
,
3744 const struct io_uring_sqe
*sqe
)
3746 #if defined(CONFIG_NET)
3747 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3749 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3753 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3760 static int io_shutdown(struct io_kiocb
*req
, bool force_nonblock
)
3762 #if defined(CONFIG_NET)
3763 struct socket
*sock
;
3769 sock
= sock_from_file(req
->file
);
3770 if (unlikely(!sock
))
3773 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3775 req_set_fail_links(req
);
3776 io_req_complete(req
, ret
);
3783 static int __io_splice_prep(struct io_kiocb
*req
,
3784 const struct io_uring_sqe
*sqe
)
3786 struct io_splice
* sp
= &req
->splice
;
3787 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3789 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3793 sp
->len
= READ_ONCE(sqe
->len
);
3794 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3796 if (unlikely(sp
->flags
& ~valid_flags
))
3799 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3800 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3803 req
->flags
|= REQ_F_NEED_CLEANUP
;
3805 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3807 * Splice operation will be punted aync, and here need to
3808 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3810 io_req_init_async(req
);
3811 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3817 static int io_tee_prep(struct io_kiocb
*req
,
3818 const struct io_uring_sqe
*sqe
)
3820 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3822 return __io_splice_prep(req
, sqe
);
3825 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
3827 struct io_splice
*sp
= &req
->splice
;
3828 struct file
*in
= sp
->file_in
;
3829 struct file
*out
= sp
->file_out
;
3830 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3836 ret
= do_tee(in
, out
, sp
->len
, flags
);
3838 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3839 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3842 req_set_fail_links(req
);
3843 io_req_complete(req
, ret
);
3847 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3849 struct io_splice
* sp
= &req
->splice
;
3851 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3852 sp
->off_out
= READ_ONCE(sqe
->off
);
3853 return __io_splice_prep(req
, sqe
);
3856 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
3858 struct io_splice
*sp
= &req
->splice
;
3859 struct file
*in
= sp
->file_in
;
3860 struct file
*out
= sp
->file_out
;
3861 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3862 loff_t
*poff_in
, *poff_out
;
3868 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3869 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3872 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3874 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3875 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3878 req_set_fail_links(req
);
3879 io_req_complete(req
, ret
);
3884 * IORING_OP_NOP just posts a completion event, nothing else.
3886 static int io_nop(struct io_kiocb
*req
, struct io_comp_state
*cs
)
3888 struct io_ring_ctx
*ctx
= req
->ctx
;
3890 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3893 __io_req_complete(req
, 0, 0, cs
);
3897 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3899 struct io_ring_ctx
*ctx
= req
->ctx
;
3904 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3906 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3909 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3910 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3913 req
->sync
.off
= READ_ONCE(sqe
->off
);
3914 req
->sync
.len
= READ_ONCE(sqe
->len
);
3918 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
3920 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3923 /* fsync always requires a blocking context */
3927 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3928 end
> 0 ? end
: LLONG_MAX
,
3929 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3931 req_set_fail_links(req
);
3932 io_req_complete(req
, ret
);
3936 static int io_fallocate_prep(struct io_kiocb
*req
,
3937 const struct io_uring_sqe
*sqe
)
3939 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3941 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3944 req
->sync
.off
= READ_ONCE(sqe
->off
);
3945 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3946 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3950 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
3954 /* fallocate always requiring blocking context */
3957 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3960 req_set_fail_links(req
);
3961 io_req_complete(req
, ret
);
3965 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3967 const char __user
*fname
;
3970 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3972 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3975 /* open.how should be already initialised */
3976 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3977 req
->open
.how
.flags
|= O_LARGEFILE
;
3979 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3980 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3981 req
->open
.filename
= getname(fname
);
3982 if (IS_ERR(req
->open
.filename
)) {
3983 ret
= PTR_ERR(req
->open
.filename
);
3984 req
->open
.filename
= NULL
;
3987 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3988 req
->open
.ignore_nonblock
= false;
3989 req
->flags
|= REQ_F_NEED_CLEANUP
;
3993 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3997 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3999 mode
= READ_ONCE(sqe
->len
);
4000 flags
= READ_ONCE(sqe
->open_flags
);
4001 req
->open
.how
= build_open_how(flags
, mode
);
4002 return __io_openat_prep(req
, sqe
);
4005 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4007 struct open_how __user
*how
;
4011 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4013 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4014 len
= READ_ONCE(sqe
->len
);
4015 if (len
< OPEN_HOW_SIZE_VER0
)
4018 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
4023 return __io_openat_prep(req
, sqe
);
4026 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
4028 struct open_flags op
;
4032 if (force_nonblock
&& !req
->open
.ignore_nonblock
)
4035 ret
= build_open_flags(&req
->open
.how
, &op
);
4039 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
4043 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
4046 ret
= PTR_ERR(file
);
4048 * A work-around to ensure that /proc/self works that way
4049 * that it should - if we get -EOPNOTSUPP back, then assume
4050 * that proc_self_get_link() failed us because we're in async
4051 * context. We should be safe to retry this from the task
4052 * itself with force_nonblock == false set, as it should not
4053 * block on lookup. Would be nice to know this upfront and
4054 * avoid the async dance, but doesn't seem feasible.
4056 if (ret
== -EOPNOTSUPP
&& io_wq_current_is_worker()) {
4057 req
->open
.ignore_nonblock
= true;
4058 refcount_inc(&req
->refs
);
4059 io_req_task_queue(req
);
4063 fsnotify_open(file
);
4064 fd_install(ret
, file
);
4067 putname(req
->open
.filename
);
4068 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4070 req_set_fail_links(req
);
4071 io_req_complete(req
, ret
);
4075 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
4077 return io_openat2(req
, force_nonblock
);
4080 static int io_remove_buffers_prep(struct io_kiocb
*req
,
4081 const struct io_uring_sqe
*sqe
)
4083 struct io_provide_buf
*p
= &req
->pbuf
;
4086 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
4089 tmp
= READ_ONCE(sqe
->fd
);
4090 if (!tmp
|| tmp
> USHRT_MAX
)
4093 memset(p
, 0, sizeof(*p
));
4095 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4099 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
4100 int bgid
, unsigned nbufs
)
4104 /* shouldn't happen */
4108 /* the head kbuf is the list itself */
4109 while (!list_empty(&buf
->list
)) {
4110 struct io_buffer
*nxt
;
4112 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
4113 list_del(&nxt
->list
);
4120 idr_remove(&ctx
->io_buffer_idr
, bgid
);
4125 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
,
4126 struct io_comp_state
*cs
)
4128 struct io_provide_buf
*p
= &req
->pbuf
;
4129 struct io_ring_ctx
*ctx
= req
->ctx
;
4130 struct io_buffer
*head
;
4133 io_ring_submit_lock(ctx
, !force_nonblock
);
4135 lockdep_assert_held(&ctx
->uring_lock
);
4138 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
4140 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
4142 req_set_fail_links(req
);
4144 /* need to hold the lock to complete IOPOLL requests */
4145 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
4146 __io_req_complete(req
, ret
, 0, cs
);
4147 io_ring_submit_unlock(ctx
, !force_nonblock
);
4149 io_ring_submit_unlock(ctx
, !force_nonblock
);
4150 __io_req_complete(req
, ret
, 0, cs
);
4155 static int io_provide_buffers_prep(struct io_kiocb
*req
,
4156 const struct io_uring_sqe
*sqe
)
4158 struct io_provide_buf
*p
= &req
->pbuf
;
4161 if (sqe
->ioprio
|| sqe
->rw_flags
)
4164 tmp
= READ_ONCE(sqe
->fd
);
4165 if (!tmp
|| tmp
> USHRT_MAX
)
4168 p
->addr
= READ_ONCE(sqe
->addr
);
4169 p
->len
= READ_ONCE(sqe
->len
);
4171 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
4174 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4175 tmp
= READ_ONCE(sqe
->off
);
4176 if (tmp
> USHRT_MAX
)
4182 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
4184 struct io_buffer
*buf
;
4185 u64 addr
= pbuf
->addr
;
4186 int i
, bid
= pbuf
->bid
;
4188 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
4189 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
4194 buf
->len
= pbuf
->len
;
4199 INIT_LIST_HEAD(&buf
->list
);
4202 list_add_tail(&buf
->list
, &(*head
)->list
);
4206 return i
? i
: -ENOMEM
;
4209 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
,
4210 struct io_comp_state
*cs
)
4212 struct io_provide_buf
*p
= &req
->pbuf
;
4213 struct io_ring_ctx
*ctx
= req
->ctx
;
4214 struct io_buffer
*head
, *list
;
4217 io_ring_submit_lock(ctx
, !force_nonblock
);
4219 lockdep_assert_held(&ctx
->uring_lock
);
4221 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
4223 ret
= io_add_buffers(p
, &head
);
4228 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
4231 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4237 req_set_fail_links(req
);
4239 /* need to hold the lock to complete IOPOLL requests */
4240 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
4241 __io_req_complete(req
, ret
, 0, cs
);
4242 io_ring_submit_unlock(ctx
, !force_nonblock
);
4244 io_ring_submit_unlock(ctx
, !force_nonblock
);
4245 __io_req_complete(req
, ret
, 0, cs
);
4250 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4251 const struct io_uring_sqe
*sqe
)
4253 #if defined(CONFIG_EPOLL)
4254 if (sqe
->ioprio
|| sqe
->buf_index
)
4256 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4259 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4260 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4261 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4263 if (ep_op_has_event(req
->epoll
.op
)) {
4264 struct epoll_event __user
*ev
;
4266 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4267 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4277 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
,
4278 struct io_comp_state
*cs
)
4280 #if defined(CONFIG_EPOLL)
4281 struct io_epoll
*ie
= &req
->epoll
;
4284 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4285 if (force_nonblock
&& ret
== -EAGAIN
)
4289 req_set_fail_links(req
);
4290 __io_req_complete(req
, ret
, 0, cs
);
4297 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4299 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4300 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4302 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4305 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4306 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4307 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4314 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
4316 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4317 struct io_madvise
*ma
= &req
->madvise
;
4323 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4325 req_set_fail_links(req
);
4326 io_req_complete(req
, ret
);
4333 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4335 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4337 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4340 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4341 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4342 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4346 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
4348 struct io_fadvise
*fa
= &req
->fadvise
;
4351 if (force_nonblock
) {
4352 switch (fa
->advice
) {
4353 case POSIX_FADV_NORMAL
:
4354 case POSIX_FADV_RANDOM
:
4355 case POSIX_FADV_SEQUENTIAL
:
4362 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4364 req_set_fail_links(req
);
4365 io_req_complete(req
, ret
);
4369 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4371 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4373 if (sqe
->ioprio
|| sqe
->buf_index
)
4375 if (req
->flags
& REQ_F_FIXED_FILE
)
4378 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4379 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4380 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4381 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4382 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4387 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
4389 struct io_statx
*ctx
= &req
->statx
;
4392 if (force_nonblock
) {
4393 /* only need file table for an actual valid fd */
4394 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
4395 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4399 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4403 req_set_fail_links(req
);
4404 io_req_complete(req
, ret
);
4408 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4411 * If we queue this for async, it must not be cancellable. That would
4412 * leave the 'file' in an undeterminate state, and here need to modify
4413 * io_wq_work.flags, so initialize io_wq_work firstly.
4415 io_req_init_async(req
);
4416 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
4418 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4420 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4421 sqe
->rw_flags
|| sqe
->buf_index
)
4423 if (req
->flags
& REQ_F_FIXED_FILE
)
4426 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4427 if ((req
->file
&& req
->file
->f_op
== &io_uring_fops
))
4430 req
->close
.put_file
= NULL
;
4434 static int io_close(struct io_kiocb
*req
, bool force_nonblock
,
4435 struct io_comp_state
*cs
)
4437 struct io_close
*close
= &req
->close
;
4440 /* might be already done during nonblock submission */
4441 if (!close
->put_file
) {
4442 ret
= close_fd_get_file(close
->fd
, &close
->put_file
);
4444 return (ret
== -ENOENT
) ? -EBADF
: ret
;
4447 /* if the file has a flush method, be safe and punt to async */
4448 if (close
->put_file
->f_op
->flush
&& force_nonblock
) {
4449 /* was never set, but play safe */
4450 req
->flags
&= ~REQ_F_NOWAIT
;
4451 /* avoid grabbing files - we don't need the files */
4452 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4456 /* No ->flush() or already async, safely close from here */
4457 ret
= filp_close(close
->put_file
, req
->work
.identity
->files
);
4459 req_set_fail_links(req
);
4460 fput(close
->put_file
);
4461 close
->put_file
= NULL
;
4462 __io_req_complete(req
, ret
, 0, cs
);
4466 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4468 struct io_ring_ctx
*ctx
= req
->ctx
;
4473 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4475 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4478 req
->sync
.off
= READ_ONCE(sqe
->off
);
4479 req
->sync
.len
= READ_ONCE(sqe
->len
);
4480 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4484 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
4488 /* sync_file_range always requires a blocking context */
4492 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4495 req_set_fail_links(req
);
4496 io_req_complete(req
, ret
);
4500 #if defined(CONFIG_NET)
4501 static int io_setup_async_msg(struct io_kiocb
*req
,
4502 struct io_async_msghdr
*kmsg
)
4504 struct io_async_msghdr
*async_msg
= req
->async_data
;
4508 if (io_alloc_async_data(req
)) {
4509 if (kmsg
->iov
!= kmsg
->fast_iov
)
4513 async_msg
= req
->async_data
;
4514 req
->flags
|= REQ_F_NEED_CLEANUP
;
4515 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4519 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4520 struct io_async_msghdr
*iomsg
)
4522 iomsg
->iov
= iomsg
->fast_iov
;
4523 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4524 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4525 req
->sr_msg
.msg_flags
, &iomsg
->iov
);
4528 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4530 struct io_async_msghdr
*async_msg
= req
->async_data
;
4531 struct io_sr_msg
*sr
= &req
->sr_msg
;
4534 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4537 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4538 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4539 sr
->len
= READ_ONCE(sqe
->len
);
4541 #ifdef CONFIG_COMPAT
4542 if (req
->ctx
->compat
)
4543 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4546 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4548 ret
= io_sendmsg_copy_hdr(req
, async_msg
);
4550 req
->flags
|= REQ_F_NEED_CLEANUP
;
4554 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4555 struct io_comp_state
*cs
)
4557 struct io_async_msghdr iomsg
, *kmsg
;
4558 struct socket
*sock
;
4562 sock
= sock_from_file(req
->file
);
4563 if (unlikely(!sock
))
4566 if (req
->async_data
) {
4567 kmsg
= req
->async_data
;
4568 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4569 /* if iov is set, it's allocated already */
4571 kmsg
->iov
= kmsg
->fast_iov
;
4572 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4574 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4580 flags
= req
->sr_msg
.msg_flags
;
4581 if (flags
& MSG_DONTWAIT
)
4582 req
->flags
|= REQ_F_NOWAIT
;
4583 else if (force_nonblock
)
4584 flags
|= MSG_DONTWAIT
;
4586 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4587 if (force_nonblock
&& ret
== -EAGAIN
)
4588 return io_setup_async_msg(req
, kmsg
);
4589 if (ret
== -ERESTARTSYS
)
4592 if (kmsg
->iov
!= kmsg
->fast_iov
)
4594 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4596 req_set_fail_links(req
);
4597 __io_req_complete(req
, ret
, 0, cs
);
4601 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4602 struct io_comp_state
*cs
)
4604 struct io_sr_msg
*sr
= &req
->sr_msg
;
4607 struct socket
*sock
;
4611 sock
= sock_from_file(req
->file
);
4612 if (unlikely(!sock
))
4615 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4619 msg
.msg_name
= NULL
;
4620 msg
.msg_control
= NULL
;
4621 msg
.msg_controllen
= 0;
4622 msg
.msg_namelen
= 0;
4624 flags
= req
->sr_msg
.msg_flags
;
4625 if (flags
& MSG_DONTWAIT
)
4626 req
->flags
|= REQ_F_NOWAIT
;
4627 else if (force_nonblock
)
4628 flags
|= MSG_DONTWAIT
;
4630 msg
.msg_flags
= flags
;
4631 ret
= sock_sendmsg(sock
, &msg
);
4632 if (force_nonblock
&& ret
== -EAGAIN
)
4634 if (ret
== -ERESTARTSYS
)
4638 req_set_fail_links(req
);
4639 __io_req_complete(req
, ret
, 0, cs
);
4643 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4644 struct io_async_msghdr
*iomsg
)
4646 struct io_sr_msg
*sr
= &req
->sr_msg
;
4647 struct iovec __user
*uiov
;
4651 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4652 &iomsg
->uaddr
, &uiov
, &iov_len
);
4656 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4659 if (copy_from_user(iomsg
->iov
, uiov
, sizeof(*uiov
)))
4661 sr
->len
= iomsg
->iov
[0].iov_len
;
4662 iov_iter_init(&iomsg
->msg
.msg_iter
, READ
, iomsg
->iov
, 1,
4666 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4667 &iomsg
->iov
, &iomsg
->msg
.msg_iter
,
4676 #ifdef CONFIG_COMPAT
4677 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4678 struct io_async_msghdr
*iomsg
)
4680 struct compat_msghdr __user
*msg_compat
;
4681 struct io_sr_msg
*sr
= &req
->sr_msg
;
4682 struct compat_iovec __user
*uiov
;
4687 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4688 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4693 uiov
= compat_ptr(ptr
);
4694 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4695 compat_ssize_t clen
;
4699 if (!access_ok(uiov
, sizeof(*uiov
)))
4701 if (__get_user(clen
, &uiov
->iov_len
))
4706 iomsg
->iov
[0].iov_len
= clen
;
4709 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4710 UIO_FASTIOV
, &iomsg
->iov
,
4711 &iomsg
->msg
.msg_iter
, true);
4720 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4721 struct io_async_msghdr
*iomsg
)
4723 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4724 iomsg
->iov
= iomsg
->fast_iov
;
4726 #ifdef CONFIG_COMPAT
4727 if (req
->ctx
->compat
)
4728 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4731 return __io_recvmsg_copy_hdr(req
, iomsg
);
4734 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4737 struct io_sr_msg
*sr
= &req
->sr_msg
;
4738 struct io_buffer
*kbuf
;
4740 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4745 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4749 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4751 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4754 static int io_recvmsg_prep(struct io_kiocb
*req
,
4755 const struct io_uring_sqe
*sqe
)
4757 struct io_async_msghdr
*async_msg
= req
->async_data
;
4758 struct io_sr_msg
*sr
= &req
->sr_msg
;
4761 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4764 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4765 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4766 sr
->len
= READ_ONCE(sqe
->len
);
4767 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4769 #ifdef CONFIG_COMPAT
4770 if (req
->ctx
->compat
)
4771 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4774 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4776 ret
= io_recvmsg_copy_hdr(req
, async_msg
);
4778 req
->flags
|= REQ_F_NEED_CLEANUP
;
4782 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4783 struct io_comp_state
*cs
)
4785 struct io_async_msghdr iomsg
, *kmsg
;
4786 struct socket
*sock
;
4787 struct io_buffer
*kbuf
;
4789 int ret
, cflags
= 0;
4791 sock
= sock_from_file(req
->file
);
4792 if (unlikely(!sock
))
4795 if (req
->async_data
) {
4796 kmsg
= req
->async_data
;
4797 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4798 /* if iov is set, it's allocated already */
4800 kmsg
->iov
= kmsg
->fast_iov
;
4801 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4803 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4809 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4810 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4812 return PTR_ERR(kbuf
);
4813 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4814 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
4815 1, req
->sr_msg
.len
);
4818 flags
= req
->sr_msg
.msg_flags
;
4819 if (flags
& MSG_DONTWAIT
)
4820 req
->flags
|= REQ_F_NOWAIT
;
4821 else if (force_nonblock
)
4822 flags
|= MSG_DONTWAIT
;
4824 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4825 kmsg
->uaddr
, flags
);
4826 if (force_nonblock
&& ret
== -EAGAIN
)
4827 return io_setup_async_msg(req
, kmsg
);
4828 if (ret
== -ERESTARTSYS
)
4831 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4832 cflags
= io_put_recv_kbuf(req
);
4833 if (kmsg
->iov
!= kmsg
->fast_iov
)
4835 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4837 req_set_fail_links(req
);
4838 __io_req_complete(req
, ret
, cflags
, cs
);
4842 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4843 struct io_comp_state
*cs
)
4845 struct io_buffer
*kbuf
;
4846 struct io_sr_msg
*sr
= &req
->sr_msg
;
4848 void __user
*buf
= sr
->buf
;
4849 struct socket
*sock
;
4852 int ret
, cflags
= 0;
4854 sock
= sock_from_file(req
->file
);
4855 if (unlikely(!sock
))
4858 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4859 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4861 return PTR_ERR(kbuf
);
4862 buf
= u64_to_user_ptr(kbuf
->addr
);
4865 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4869 msg
.msg_name
= NULL
;
4870 msg
.msg_control
= NULL
;
4871 msg
.msg_controllen
= 0;
4872 msg
.msg_namelen
= 0;
4873 msg
.msg_iocb
= NULL
;
4876 flags
= req
->sr_msg
.msg_flags
;
4877 if (flags
& MSG_DONTWAIT
)
4878 req
->flags
|= REQ_F_NOWAIT
;
4879 else if (force_nonblock
)
4880 flags
|= MSG_DONTWAIT
;
4882 ret
= sock_recvmsg(sock
, &msg
, flags
);
4883 if (force_nonblock
&& ret
== -EAGAIN
)
4885 if (ret
== -ERESTARTSYS
)
4888 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4889 cflags
= io_put_recv_kbuf(req
);
4891 req_set_fail_links(req
);
4892 __io_req_complete(req
, ret
, cflags
, cs
);
4896 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4898 struct io_accept
*accept
= &req
->accept
;
4900 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4902 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4905 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4906 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4907 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4908 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4912 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4913 struct io_comp_state
*cs
)
4915 struct io_accept
*accept
= &req
->accept
;
4916 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4919 if (req
->file
->f_flags
& O_NONBLOCK
)
4920 req
->flags
|= REQ_F_NOWAIT
;
4922 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4923 accept
->addr_len
, accept
->flags
,
4925 if (ret
== -EAGAIN
&& force_nonblock
)
4928 if (ret
== -ERESTARTSYS
)
4930 req_set_fail_links(req
);
4932 __io_req_complete(req
, ret
, 0, cs
);
4936 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4938 struct io_connect
*conn
= &req
->connect
;
4939 struct io_async_connect
*io
= req
->async_data
;
4941 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4943 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4946 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4947 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4952 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4956 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4957 struct io_comp_state
*cs
)
4959 struct io_async_connect __io
, *io
;
4960 unsigned file_flags
;
4963 if (req
->async_data
) {
4964 io
= req
->async_data
;
4966 ret
= move_addr_to_kernel(req
->connect
.addr
,
4967 req
->connect
.addr_len
,
4974 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4976 ret
= __sys_connect_file(req
->file
, &io
->address
,
4977 req
->connect
.addr_len
, file_flags
);
4978 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4979 if (req
->async_data
)
4981 if (io_alloc_async_data(req
)) {
4985 io
= req
->async_data
;
4986 memcpy(req
->async_data
, &__io
, sizeof(__io
));
4989 if (ret
== -ERESTARTSYS
)
4993 req_set_fail_links(req
);
4994 __io_req_complete(req
, ret
, 0, cs
);
4997 #else /* !CONFIG_NET */
4998 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5003 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
5004 struct io_comp_state
*cs
)
5009 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
5010 struct io_comp_state
*cs
)
5015 static int io_recvmsg_prep(struct io_kiocb
*req
,
5016 const struct io_uring_sqe
*sqe
)
5021 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
5022 struct io_comp_state
*cs
)
5027 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
5028 struct io_comp_state
*cs
)
5033 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5038 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
5039 struct io_comp_state
*cs
)
5044 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5049 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
5050 struct io_comp_state
*cs
)
5054 #endif /* CONFIG_NET */
5056 struct io_poll_table
{
5057 struct poll_table_struct pt
;
5058 struct io_kiocb
*req
;
5062 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
5063 __poll_t mask
, task_work_func_t func
)
5067 /* for instances that support it check for an event match first: */
5068 if (mask
&& !(mask
& poll
->events
))
5071 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
5073 list_del_init(&poll
->wait
.entry
);
5076 init_task_work(&req
->task_work
, func
);
5077 percpu_ref_get(&req
->ctx
->refs
);
5080 * If this fails, then the task is exiting. When a task exits, the
5081 * work gets canceled, so just cancel this request as well instead
5082 * of executing it. We can't safely execute it anyway, as we may not
5083 * have the needed state needed for it anyway.
5085 ret
= io_req_task_work_add(req
);
5086 if (unlikely(ret
)) {
5087 struct task_struct
*tsk
;
5089 WRITE_ONCE(poll
->canceled
, true);
5090 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
5091 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
5092 wake_up_process(tsk
);
5097 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
5098 __acquires(&req
->ctx
->completion_lock
)
5100 struct io_ring_ctx
*ctx
= req
->ctx
;
5102 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5103 struct poll_table_struct pt
= { ._key
= poll
->events
};
5105 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
5108 spin_lock_irq(&ctx
->completion_lock
);
5109 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5110 add_wait_queue(poll
->head
, &poll
->wait
);
5117 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
5119 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
5120 if (req
->opcode
== IORING_OP_POLL_ADD
)
5121 return req
->async_data
;
5122 return req
->apoll
->double_poll
;
5125 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
5127 if (req
->opcode
== IORING_OP_POLL_ADD
)
5129 return &req
->apoll
->poll
;
5132 static void io_poll_remove_double(struct io_kiocb
*req
)
5134 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
5136 lockdep_assert_held(&req
->ctx
->completion_lock
);
5138 if (poll
&& poll
->head
) {
5139 struct wait_queue_head
*head
= poll
->head
;
5141 spin_lock(&head
->lock
);
5142 list_del_init(&poll
->wait
.entry
);
5143 if (poll
->wait
.private)
5144 refcount_dec(&req
->refs
);
5146 spin_unlock(&head
->lock
);
5150 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
5152 struct io_ring_ctx
*ctx
= req
->ctx
;
5154 io_poll_remove_double(req
);
5155 req
->poll
.done
= true;
5156 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
5157 io_commit_cqring(ctx
);
5160 static void io_poll_task_func(struct callback_head
*cb
)
5162 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5163 struct io_ring_ctx
*ctx
= req
->ctx
;
5164 struct io_kiocb
*nxt
;
5166 if (io_poll_rewait(req
, &req
->poll
)) {
5167 spin_unlock_irq(&ctx
->completion_lock
);
5169 hash_del(&req
->hash_node
);
5170 io_poll_complete(req
, req
->result
, 0);
5171 spin_unlock_irq(&ctx
->completion_lock
);
5173 nxt
= io_put_req_find_next(req
);
5174 io_cqring_ev_posted(ctx
);
5176 __io_req_task_submit(nxt
);
5179 percpu_ref_put(&ctx
->refs
);
5182 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
5183 int sync
, void *key
)
5185 struct io_kiocb
*req
= wait
->private;
5186 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
5187 __poll_t mask
= key_to_poll(key
);
5189 /* for instances that support it check for an event match first: */
5190 if (mask
&& !(mask
& poll
->events
))
5193 list_del_init(&wait
->entry
);
5195 if (poll
&& poll
->head
) {
5198 spin_lock(&poll
->head
->lock
);
5199 done
= list_empty(&poll
->wait
.entry
);
5201 list_del_init(&poll
->wait
.entry
);
5202 /* make sure double remove sees this as being gone */
5203 wait
->private = NULL
;
5204 spin_unlock(&poll
->head
->lock
);
5206 /* use wait func handler, so it matches the rq type */
5207 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5210 refcount_dec(&req
->refs
);
5214 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
5215 wait_queue_func_t wake_func
)
5219 poll
->canceled
= false;
5220 poll
->events
= events
;
5221 INIT_LIST_HEAD(&poll
->wait
.entry
);
5222 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5225 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5226 struct wait_queue_head
*head
,
5227 struct io_poll_iocb
**poll_ptr
)
5229 struct io_kiocb
*req
= pt
->req
;
5232 * If poll->head is already set, it's because the file being polled
5233 * uses multiple waitqueues for poll handling (eg one for read, one
5234 * for write). Setup a separate io_poll_iocb if this happens.
5236 if (unlikely(poll
->head
)) {
5237 struct io_poll_iocb
*poll_one
= poll
;
5239 /* already have a 2nd entry, fail a third attempt */
5241 pt
->error
= -EINVAL
;
5244 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5246 pt
->error
= -ENOMEM
;
5249 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5250 refcount_inc(&req
->refs
);
5251 poll
->wait
.private = req
;
5258 if (poll
->events
& EPOLLEXCLUSIVE
)
5259 add_wait_queue_exclusive(head
, &poll
->wait
);
5261 add_wait_queue(head
, &poll
->wait
);
5264 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5265 struct poll_table_struct
*p
)
5267 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5268 struct async_poll
*apoll
= pt
->req
->apoll
;
5270 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5273 static void io_async_task_func(struct callback_head
*cb
)
5275 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5276 struct async_poll
*apoll
= req
->apoll
;
5277 struct io_ring_ctx
*ctx
= req
->ctx
;
5279 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5281 if (io_poll_rewait(req
, &apoll
->poll
)) {
5282 spin_unlock_irq(&ctx
->completion_lock
);
5283 percpu_ref_put(&ctx
->refs
);
5287 /* If req is still hashed, it cannot have been canceled. Don't check. */
5288 if (hash_hashed(&req
->hash_node
))
5289 hash_del(&req
->hash_node
);
5291 io_poll_remove_double(req
);
5292 spin_unlock_irq(&ctx
->completion_lock
);
5294 if (!READ_ONCE(apoll
->poll
.canceled
))
5295 __io_req_task_submit(req
);
5297 __io_req_task_cancel(req
, -ECANCELED
);
5299 percpu_ref_put(&ctx
->refs
);
5300 kfree(apoll
->double_poll
);
5304 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5307 struct io_kiocb
*req
= wait
->private;
5308 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5310 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5313 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5316 static void io_poll_req_insert(struct io_kiocb
*req
)
5318 struct io_ring_ctx
*ctx
= req
->ctx
;
5319 struct hlist_head
*list
;
5321 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5322 hlist_add_head(&req
->hash_node
, list
);
5325 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5326 struct io_poll_iocb
*poll
,
5327 struct io_poll_table
*ipt
, __poll_t mask
,
5328 wait_queue_func_t wake_func
)
5329 __acquires(&ctx
->completion_lock
)
5331 struct io_ring_ctx
*ctx
= req
->ctx
;
5332 bool cancel
= false;
5334 INIT_HLIST_NODE(&req
->hash_node
);
5335 io_init_poll_iocb(poll
, mask
, wake_func
);
5336 poll
->file
= req
->file
;
5337 poll
->wait
.private = req
;
5339 ipt
->pt
._key
= mask
;
5341 ipt
->error
= -EINVAL
;
5343 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5345 spin_lock_irq(&ctx
->completion_lock
);
5346 if (likely(poll
->head
)) {
5347 spin_lock(&poll
->head
->lock
);
5348 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5354 if (mask
|| ipt
->error
)
5355 list_del_init(&poll
->wait
.entry
);
5357 WRITE_ONCE(poll
->canceled
, true);
5358 else if (!poll
->done
) /* actually waiting for an event */
5359 io_poll_req_insert(req
);
5360 spin_unlock(&poll
->head
->lock
);
5366 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5368 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5369 struct io_ring_ctx
*ctx
= req
->ctx
;
5370 struct async_poll
*apoll
;
5371 struct io_poll_table ipt
;
5375 if (!req
->file
|| !file_can_poll(req
->file
))
5377 if (req
->flags
& REQ_F_POLLED
)
5381 else if (def
->pollout
)
5385 /* if we can't nonblock try, then no point in arming a poll handler */
5386 if (!io_file_supports_async(req
->file
, rw
))
5389 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5390 if (unlikely(!apoll
))
5392 apoll
->double_poll
= NULL
;
5394 req
->flags
|= REQ_F_POLLED
;
5399 mask
|= POLLIN
| POLLRDNORM
;
5401 mask
|= POLLOUT
| POLLWRNORM
;
5403 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5404 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5405 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5408 mask
|= POLLERR
| POLLPRI
;
5410 ipt
.pt
._qproc
= io_async_queue_proc
;
5412 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5414 if (ret
|| ipt
.error
) {
5415 io_poll_remove_double(req
);
5416 spin_unlock_irq(&ctx
->completion_lock
);
5417 kfree(apoll
->double_poll
);
5421 spin_unlock_irq(&ctx
->completion_lock
);
5422 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5423 apoll
->poll
.events
);
5427 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5428 struct io_poll_iocb
*poll
)
5430 bool do_complete
= false;
5432 spin_lock(&poll
->head
->lock
);
5433 WRITE_ONCE(poll
->canceled
, true);
5434 if (!list_empty(&poll
->wait
.entry
)) {
5435 list_del_init(&poll
->wait
.entry
);
5438 spin_unlock(&poll
->head
->lock
);
5439 hash_del(&req
->hash_node
);
5443 static bool io_poll_remove_one(struct io_kiocb
*req
)
5447 io_poll_remove_double(req
);
5449 if (req
->opcode
== IORING_OP_POLL_ADD
) {
5450 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
5452 struct async_poll
*apoll
= req
->apoll
;
5454 /* non-poll requests have submit ref still */
5455 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
5458 kfree(apoll
->double_poll
);
5464 io_cqring_fill_event(req
, -ECANCELED
);
5465 io_commit_cqring(req
->ctx
);
5466 req_set_fail_links(req
);
5467 io_put_req_deferred(req
, 1);
5474 * Returns true if we found and killed one or more poll requests
5476 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5477 struct files_struct
*files
)
5479 struct hlist_node
*tmp
;
5480 struct io_kiocb
*req
;
5483 spin_lock_irq(&ctx
->completion_lock
);
5484 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5485 struct hlist_head
*list
;
5487 list
= &ctx
->cancel_hash
[i
];
5488 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5489 if (io_match_task(req
, tsk
, files
))
5490 posted
+= io_poll_remove_one(req
);
5493 spin_unlock_irq(&ctx
->completion_lock
);
5496 io_cqring_ev_posted(ctx
);
5501 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5503 struct hlist_head
*list
;
5504 struct io_kiocb
*req
;
5506 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5507 hlist_for_each_entry(req
, list
, hash_node
) {
5508 if (sqe_addr
!= req
->user_data
)
5510 if (io_poll_remove_one(req
))
5518 static int io_poll_remove_prep(struct io_kiocb
*req
,
5519 const struct io_uring_sqe
*sqe
)
5521 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5523 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5527 req
->poll_remove
.addr
= READ_ONCE(sqe
->addr
);
5532 * Find a running poll command that matches one specified in sqe->addr,
5533 * and remove it if found.
5535 static int io_poll_remove(struct io_kiocb
*req
)
5537 struct io_ring_ctx
*ctx
= req
->ctx
;
5540 spin_lock_irq(&ctx
->completion_lock
);
5541 ret
= io_poll_cancel(ctx
, req
->poll_remove
.addr
);
5542 spin_unlock_irq(&ctx
->completion_lock
);
5545 req_set_fail_links(req
);
5546 io_req_complete(req
, ret
);
5550 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5553 struct io_kiocb
*req
= wait
->private;
5554 struct io_poll_iocb
*poll
= &req
->poll
;
5556 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5559 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5560 struct poll_table_struct
*p
)
5562 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5564 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5567 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5569 struct io_poll_iocb
*poll
= &req
->poll
;
5572 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5574 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
5577 events
= READ_ONCE(sqe
->poll32_events
);
5579 events
= swahw32(events
);
5581 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
5582 (events
& EPOLLEXCLUSIVE
);
5586 static int io_poll_add(struct io_kiocb
*req
)
5588 struct io_poll_iocb
*poll
= &req
->poll
;
5589 struct io_ring_ctx
*ctx
= req
->ctx
;
5590 struct io_poll_table ipt
;
5593 ipt
.pt
._qproc
= io_poll_queue_proc
;
5595 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5598 if (mask
) { /* no async, we'd stolen it */
5600 io_poll_complete(req
, mask
, 0);
5602 spin_unlock_irq(&ctx
->completion_lock
);
5605 io_cqring_ev_posted(ctx
);
5611 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5613 struct io_timeout_data
*data
= container_of(timer
,
5614 struct io_timeout_data
, timer
);
5615 struct io_kiocb
*req
= data
->req
;
5616 struct io_ring_ctx
*ctx
= req
->ctx
;
5617 unsigned long flags
;
5619 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5620 list_del_init(&req
->timeout
.list
);
5621 atomic_set(&req
->ctx
->cq_timeouts
,
5622 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5624 io_cqring_fill_event(req
, -ETIME
);
5625 io_commit_cqring(ctx
);
5626 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5628 io_cqring_ev_posted(ctx
);
5629 req_set_fail_links(req
);
5631 return HRTIMER_NORESTART
;
5634 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5637 struct io_timeout_data
*io
;
5638 struct io_kiocb
*req
;
5641 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5642 if (user_data
== req
->user_data
) {
5649 return ERR_PTR(ret
);
5651 io
= req
->async_data
;
5652 ret
= hrtimer_try_to_cancel(&io
->timer
);
5654 return ERR_PTR(-EALREADY
);
5655 list_del_init(&req
->timeout
.list
);
5659 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5661 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5664 return PTR_ERR(req
);
5666 req_set_fail_links(req
);
5667 io_cqring_fill_event(req
, -ECANCELED
);
5668 io_put_req_deferred(req
, 1);
5672 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
5673 struct timespec64
*ts
, enum hrtimer_mode mode
)
5675 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5676 struct io_timeout_data
*data
;
5679 return PTR_ERR(req
);
5681 req
->timeout
.off
= 0; /* noseq */
5682 data
= req
->async_data
;
5683 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
5684 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, mode
);
5685 data
->timer
.function
= io_timeout_fn
;
5686 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
5690 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5691 const struct io_uring_sqe
*sqe
)
5693 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5695 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5697 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5699 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5702 tr
->addr
= READ_ONCE(sqe
->addr
);
5703 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
5704 if (tr
->flags
& IORING_TIMEOUT_UPDATE
) {
5705 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE
|IORING_TIMEOUT_ABS
))
5707 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
5709 } else if (tr
->flags
) {
5710 /* timeout removal doesn't support flags */
5718 * Remove or update an existing timeout command
5720 static int io_timeout_remove(struct io_kiocb
*req
)
5722 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5723 struct io_ring_ctx
*ctx
= req
->ctx
;
5726 spin_lock_irq(&ctx
->completion_lock
);
5727 if (req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
) {
5728 enum hrtimer_mode mode
= (tr
->flags
& IORING_TIMEOUT_ABS
)
5729 ? HRTIMER_MODE_ABS
: HRTIMER_MODE_REL
;
5731 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
, mode
);
5733 ret
= io_timeout_cancel(ctx
, tr
->addr
);
5736 io_cqring_fill_event(req
, ret
);
5737 io_commit_cqring(ctx
);
5738 spin_unlock_irq(&ctx
->completion_lock
);
5739 io_cqring_ev_posted(ctx
);
5741 req_set_fail_links(req
);
5746 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5747 bool is_timeout_link
)
5749 struct io_timeout_data
*data
;
5751 u32 off
= READ_ONCE(sqe
->off
);
5753 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5755 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5757 if (off
&& is_timeout_link
)
5759 flags
= READ_ONCE(sqe
->timeout_flags
);
5760 if (flags
& ~IORING_TIMEOUT_ABS
)
5763 req
->timeout
.off
= off
;
5765 if (!req
->async_data
&& io_alloc_async_data(req
))
5768 data
= req
->async_data
;
5771 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5774 if (flags
& IORING_TIMEOUT_ABS
)
5775 data
->mode
= HRTIMER_MODE_ABS
;
5777 data
->mode
= HRTIMER_MODE_REL
;
5779 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5783 static int io_timeout(struct io_kiocb
*req
)
5785 struct io_ring_ctx
*ctx
= req
->ctx
;
5786 struct io_timeout_data
*data
= req
->async_data
;
5787 struct list_head
*entry
;
5788 u32 tail
, off
= req
->timeout
.off
;
5790 spin_lock_irq(&ctx
->completion_lock
);
5793 * sqe->off holds how many events that need to occur for this
5794 * timeout event to be satisfied. If it isn't set, then this is
5795 * a pure timeout request, sequence isn't used.
5797 if (io_is_timeout_noseq(req
)) {
5798 entry
= ctx
->timeout_list
.prev
;
5802 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5803 req
->timeout
.target_seq
= tail
+ off
;
5806 * Insertion sort, ensuring the first entry in the list is always
5807 * the one we need first.
5809 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5810 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5813 if (io_is_timeout_noseq(nxt
))
5815 /* nxt.seq is behind @tail, otherwise would've been completed */
5816 if (off
>= nxt
->timeout
.target_seq
- tail
)
5820 list_add(&req
->timeout
.list
, entry
);
5821 data
->timer
.function
= io_timeout_fn
;
5822 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5823 spin_unlock_irq(&ctx
->completion_lock
);
5827 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5829 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5831 return req
->user_data
== (unsigned long) data
;
5834 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5836 enum io_wq_cancel cancel_ret
;
5839 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5840 switch (cancel_ret
) {
5841 case IO_WQ_CANCEL_OK
:
5844 case IO_WQ_CANCEL_RUNNING
:
5847 case IO_WQ_CANCEL_NOTFOUND
:
5855 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5856 struct io_kiocb
*req
, __u64 sqe_addr
,
5859 unsigned long flags
;
5862 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5863 if (ret
!= -ENOENT
) {
5864 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5868 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5869 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5872 ret
= io_poll_cancel(ctx
, sqe_addr
);
5876 io_cqring_fill_event(req
, ret
);
5877 io_commit_cqring(ctx
);
5878 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5879 io_cqring_ev_posted(ctx
);
5882 req_set_fail_links(req
);
5886 static int io_async_cancel_prep(struct io_kiocb
*req
,
5887 const struct io_uring_sqe
*sqe
)
5889 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5891 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5893 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5896 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5900 static int io_async_cancel(struct io_kiocb
*req
)
5902 struct io_ring_ctx
*ctx
= req
->ctx
;
5904 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
5908 static int io_files_update_prep(struct io_kiocb
*req
,
5909 const struct io_uring_sqe
*sqe
)
5911 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
5913 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5915 if (sqe
->ioprio
|| sqe
->rw_flags
)
5918 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
5919 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
5920 if (!req
->files_update
.nr_args
)
5922 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
5926 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
,
5927 struct io_comp_state
*cs
)
5929 struct io_ring_ctx
*ctx
= req
->ctx
;
5930 struct io_uring_files_update up
;
5936 up
.offset
= req
->files_update
.offset
;
5937 up
.fds
= req
->files_update
.arg
;
5939 mutex_lock(&ctx
->uring_lock
);
5940 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
5941 mutex_unlock(&ctx
->uring_lock
);
5944 req_set_fail_links(req
);
5945 __io_req_complete(req
, ret
, 0, cs
);
5949 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5951 switch (req
->opcode
) {
5954 case IORING_OP_READV
:
5955 case IORING_OP_READ_FIXED
:
5956 case IORING_OP_READ
:
5957 return io_read_prep(req
, sqe
);
5958 case IORING_OP_WRITEV
:
5959 case IORING_OP_WRITE_FIXED
:
5960 case IORING_OP_WRITE
:
5961 return io_write_prep(req
, sqe
);
5962 case IORING_OP_POLL_ADD
:
5963 return io_poll_add_prep(req
, sqe
);
5964 case IORING_OP_POLL_REMOVE
:
5965 return io_poll_remove_prep(req
, sqe
);
5966 case IORING_OP_FSYNC
:
5967 return io_prep_fsync(req
, sqe
);
5968 case IORING_OP_SYNC_FILE_RANGE
:
5969 return io_prep_sfr(req
, sqe
);
5970 case IORING_OP_SENDMSG
:
5971 case IORING_OP_SEND
:
5972 return io_sendmsg_prep(req
, sqe
);
5973 case IORING_OP_RECVMSG
:
5974 case IORING_OP_RECV
:
5975 return io_recvmsg_prep(req
, sqe
);
5976 case IORING_OP_CONNECT
:
5977 return io_connect_prep(req
, sqe
);
5978 case IORING_OP_TIMEOUT
:
5979 return io_timeout_prep(req
, sqe
, false);
5980 case IORING_OP_TIMEOUT_REMOVE
:
5981 return io_timeout_remove_prep(req
, sqe
);
5982 case IORING_OP_ASYNC_CANCEL
:
5983 return io_async_cancel_prep(req
, sqe
);
5984 case IORING_OP_LINK_TIMEOUT
:
5985 return io_timeout_prep(req
, sqe
, true);
5986 case IORING_OP_ACCEPT
:
5987 return io_accept_prep(req
, sqe
);
5988 case IORING_OP_FALLOCATE
:
5989 return io_fallocate_prep(req
, sqe
);
5990 case IORING_OP_OPENAT
:
5991 return io_openat_prep(req
, sqe
);
5992 case IORING_OP_CLOSE
:
5993 return io_close_prep(req
, sqe
);
5994 case IORING_OP_FILES_UPDATE
:
5995 return io_files_update_prep(req
, sqe
);
5996 case IORING_OP_STATX
:
5997 return io_statx_prep(req
, sqe
);
5998 case IORING_OP_FADVISE
:
5999 return io_fadvise_prep(req
, sqe
);
6000 case IORING_OP_MADVISE
:
6001 return io_madvise_prep(req
, sqe
);
6002 case IORING_OP_OPENAT2
:
6003 return io_openat2_prep(req
, sqe
);
6004 case IORING_OP_EPOLL_CTL
:
6005 return io_epoll_ctl_prep(req
, sqe
);
6006 case IORING_OP_SPLICE
:
6007 return io_splice_prep(req
, sqe
);
6008 case IORING_OP_PROVIDE_BUFFERS
:
6009 return io_provide_buffers_prep(req
, sqe
);
6010 case IORING_OP_REMOVE_BUFFERS
:
6011 return io_remove_buffers_prep(req
, sqe
);
6013 return io_tee_prep(req
, sqe
);
6014 case IORING_OP_SHUTDOWN
:
6015 return io_shutdown_prep(req
, sqe
);
6016 case IORING_OP_RENAMEAT
:
6017 return io_renameat_prep(req
, sqe
);
6018 case IORING_OP_UNLINKAT
:
6019 return io_unlinkat_prep(req
, sqe
);
6022 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
6027 static int io_req_defer_prep(struct io_kiocb
*req
,
6028 const struct io_uring_sqe
*sqe
)
6032 if (io_alloc_async_data(req
))
6034 return io_req_prep(req
, sqe
);
6037 static u32
io_get_sequence(struct io_kiocb
*req
)
6039 struct io_kiocb
*pos
;
6040 struct io_ring_ctx
*ctx
= req
->ctx
;
6041 u32 total_submitted
, nr_reqs
= 0;
6043 io_for_each_link(pos
, req
)
6046 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
6047 return total_submitted
- nr_reqs
;
6050 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6052 struct io_ring_ctx
*ctx
= req
->ctx
;
6053 struct io_defer_entry
*de
;
6057 /* Still need defer if there is pending req in defer list. */
6058 if (likely(list_empty_careful(&ctx
->defer_list
) &&
6059 !(req
->flags
& REQ_F_IO_DRAIN
)))
6062 seq
= io_get_sequence(req
);
6063 /* Still a chance to pass the sequence check */
6064 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
6067 if (!req
->async_data
) {
6068 ret
= io_req_defer_prep(req
, sqe
);
6072 io_prep_async_link(req
);
6073 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
6077 spin_lock_irq(&ctx
->completion_lock
);
6078 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
6079 spin_unlock_irq(&ctx
->completion_lock
);
6081 io_queue_async_work(req
);
6082 return -EIOCBQUEUED
;
6085 trace_io_uring_defer(ctx
, req
, req
->user_data
);
6088 list_add_tail(&de
->list
, &ctx
->defer_list
);
6089 spin_unlock_irq(&ctx
->completion_lock
);
6090 return -EIOCBQUEUED
;
6093 static void io_req_drop_files(struct io_kiocb
*req
)
6095 struct io_ring_ctx
*ctx
= req
->ctx
;
6096 struct io_uring_task
*tctx
= req
->task
->io_uring
;
6097 unsigned long flags
;
6099 put_files_struct(req
->work
.identity
->files
);
6100 put_nsproxy(req
->work
.identity
->nsproxy
);
6101 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
6102 list_del(&req
->inflight_entry
);
6103 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
6104 req
->flags
&= ~REQ_F_INFLIGHT
;
6105 req
->work
.flags
&= ~IO_WQ_WORK_FILES
;
6106 if (atomic_read(&tctx
->in_idle
))
6107 wake_up(&tctx
->wait
);
6110 static void __io_clean_op(struct io_kiocb
*req
)
6112 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6113 switch (req
->opcode
) {
6114 case IORING_OP_READV
:
6115 case IORING_OP_READ_FIXED
:
6116 case IORING_OP_READ
:
6117 kfree((void *)(unsigned long)req
->rw
.addr
);
6119 case IORING_OP_RECVMSG
:
6120 case IORING_OP_RECV
:
6121 kfree(req
->sr_msg
.kbuf
);
6124 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
6127 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6128 switch (req
->opcode
) {
6129 case IORING_OP_READV
:
6130 case IORING_OP_READ_FIXED
:
6131 case IORING_OP_READ
:
6132 case IORING_OP_WRITEV
:
6133 case IORING_OP_WRITE_FIXED
:
6134 case IORING_OP_WRITE
: {
6135 struct io_async_rw
*io
= req
->async_data
;
6137 kfree(io
->free_iovec
);
6140 case IORING_OP_RECVMSG
:
6141 case IORING_OP_SENDMSG
: {
6142 struct io_async_msghdr
*io
= req
->async_data
;
6143 if (io
->iov
!= io
->fast_iov
)
6147 case IORING_OP_SPLICE
:
6149 io_put_file(req
, req
->splice
.file_in
,
6150 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
6152 case IORING_OP_OPENAT
:
6153 case IORING_OP_OPENAT2
:
6154 if (req
->open
.filename
)
6155 putname(req
->open
.filename
);
6157 case IORING_OP_RENAMEAT
:
6158 putname(req
->rename
.oldpath
);
6159 putname(req
->rename
.newpath
);
6161 case IORING_OP_UNLINKAT
:
6162 putname(req
->unlink
.filename
);
6165 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
6168 if (req
->flags
& REQ_F_INFLIGHT
)
6169 io_req_drop_files(req
);
6172 static int io_issue_sqe(struct io_kiocb
*req
, bool force_nonblock
,
6173 struct io_comp_state
*cs
)
6175 struct io_ring_ctx
*ctx
= req
->ctx
;
6178 switch (req
->opcode
) {
6180 ret
= io_nop(req
, cs
);
6182 case IORING_OP_READV
:
6183 case IORING_OP_READ_FIXED
:
6184 case IORING_OP_READ
:
6185 ret
= io_read(req
, force_nonblock
, cs
);
6187 case IORING_OP_WRITEV
:
6188 case IORING_OP_WRITE_FIXED
:
6189 case IORING_OP_WRITE
:
6190 ret
= io_write(req
, force_nonblock
, cs
);
6192 case IORING_OP_FSYNC
:
6193 ret
= io_fsync(req
, force_nonblock
);
6195 case IORING_OP_POLL_ADD
:
6196 ret
= io_poll_add(req
);
6198 case IORING_OP_POLL_REMOVE
:
6199 ret
= io_poll_remove(req
);
6201 case IORING_OP_SYNC_FILE_RANGE
:
6202 ret
= io_sync_file_range(req
, force_nonblock
);
6204 case IORING_OP_SENDMSG
:
6205 ret
= io_sendmsg(req
, force_nonblock
, cs
);
6207 case IORING_OP_SEND
:
6208 ret
= io_send(req
, force_nonblock
, cs
);
6210 case IORING_OP_RECVMSG
:
6211 ret
= io_recvmsg(req
, force_nonblock
, cs
);
6213 case IORING_OP_RECV
:
6214 ret
= io_recv(req
, force_nonblock
, cs
);
6216 case IORING_OP_TIMEOUT
:
6217 ret
= io_timeout(req
);
6219 case IORING_OP_TIMEOUT_REMOVE
:
6220 ret
= io_timeout_remove(req
);
6222 case IORING_OP_ACCEPT
:
6223 ret
= io_accept(req
, force_nonblock
, cs
);
6225 case IORING_OP_CONNECT
:
6226 ret
= io_connect(req
, force_nonblock
, cs
);
6228 case IORING_OP_ASYNC_CANCEL
:
6229 ret
= io_async_cancel(req
);
6231 case IORING_OP_FALLOCATE
:
6232 ret
= io_fallocate(req
, force_nonblock
);
6234 case IORING_OP_OPENAT
:
6235 ret
= io_openat(req
, force_nonblock
);
6237 case IORING_OP_CLOSE
:
6238 ret
= io_close(req
, force_nonblock
, cs
);
6240 case IORING_OP_FILES_UPDATE
:
6241 ret
= io_files_update(req
, force_nonblock
, cs
);
6243 case IORING_OP_STATX
:
6244 ret
= io_statx(req
, force_nonblock
);
6246 case IORING_OP_FADVISE
:
6247 ret
= io_fadvise(req
, force_nonblock
);
6249 case IORING_OP_MADVISE
:
6250 ret
= io_madvise(req
, force_nonblock
);
6252 case IORING_OP_OPENAT2
:
6253 ret
= io_openat2(req
, force_nonblock
);
6255 case IORING_OP_EPOLL_CTL
:
6256 ret
= io_epoll_ctl(req
, force_nonblock
, cs
);
6258 case IORING_OP_SPLICE
:
6259 ret
= io_splice(req
, force_nonblock
);
6261 case IORING_OP_PROVIDE_BUFFERS
:
6262 ret
= io_provide_buffers(req
, force_nonblock
, cs
);
6264 case IORING_OP_REMOVE_BUFFERS
:
6265 ret
= io_remove_buffers(req
, force_nonblock
, cs
);
6268 ret
= io_tee(req
, force_nonblock
);
6270 case IORING_OP_SHUTDOWN
:
6271 ret
= io_shutdown(req
, force_nonblock
);
6273 case IORING_OP_RENAMEAT
:
6274 ret
= io_renameat(req
, force_nonblock
);
6276 case IORING_OP_UNLINKAT
:
6277 ret
= io_unlinkat(req
, force_nonblock
);
6287 /* If the op doesn't have a file, we're not polling for it */
6288 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
6289 const bool in_async
= io_wq_current_is_worker();
6291 /* workqueue context doesn't hold uring_lock, grab it now */
6293 mutex_lock(&ctx
->uring_lock
);
6295 io_iopoll_req_issued(req
, in_async
);
6298 mutex_unlock(&ctx
->uring_lock
);
6304 static struct io_wq_work
*io_wq_submit_work(struct io_wq_work
*work
)
6306 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6307 struct io_kiocb
*timeout
;
6310 timeout
= io_prep_linked_timeout(req
);
6312 io_queue_linked_timeout(timeout
);
6314 /* if NO_CANCEL is set, we must still run the work */
6315 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
6316 IO_WQ_WORK_CANCEL
) {
6322 ret
= io_issue_sqe(req
, false, NULL
);
6324 * We can get EAGAIN for polled IO even though we're
6325 * forcing a sync submission from here, since we can't
6326 * wait for request slots on the block side.
6335 struct io_ring_ctx
*lock_ctx
= NULL
;
6337 if (req
->ctx
->flags
& IORING_SETUP_IOPOLL
)
6338 lock_ctx
= req
->ctx
;
6341 * io_iopoll_complete() does not hold completion_lock to
6342 * complete polled io, so here for polled io, we can not call
6343 * io_req_complete() directly, otherwise there maybe concurrent
6344 * access to cqring, defer_list, etc, which is not safe. Given
6345 * that io_iopoll_complete() is always called under uring_lock,
6346 * so here for polled io, we also get uring_lock to complete
6350 mutex_lock(&lock_ctx
->uring_lock
);
6352 req_set_fail_links(req
);
6353 io_req_complete(req
, ret
);
6356 mutex_unlock(&lock_ctx
->uring_lock
);
6359 return io_steal_work(req
);
6362 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6365 struct fixed_file_table
*table
;
6367 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
6368 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
6371 static struct file
*io_file_get(struct io_submit_state
*state
,
6372 struct io_kiocb
*req
, int fd
, bool fixed
)
6374 struct io_ring_ctx
*ctx
= req
->ctx
;
6378 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6380 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6381 file
= io_file_from_index(ctx
, fd
);
6382 io_set_resource_node(req
);
6384 trace_io_uring_file_get(ctx
, fd
);
6385 file
= __io_file_get(state
, fd
);
6391 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6393 struct io_timeout_data
*data
= container_of(timer
,
6394 struct io_timeout_data
, timer
);
6395 struct io_kiocb
*prev
, *req
= data
->req
;
6396 struct io_ring_ctx
*ctx
= req
->ctx
;
6397 unsigned long flags
;
6399 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6400 prev
= req
->timeout
.head
;
6401 req
->timeout
.head
= NULL
;
6404 * We don't expect the list to be empty, that will only happen if we
6405 * race with the completion of the linked work.
6407 if (prev
&& refcount_inc_not_zero(&prev
->refs
))
6408 io_remove_next_linked(prev
);
6411 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6414 req_set_fail_links(prev
);
6415 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6418 io_req_complete(req
, -ETIME
);
6420 return HRTIMER_NORESTART
;
6423 static void __io_queue_linked_timeout(struct io_kiocb
*req
)
6426 * If the back reference is NULL, then our linked request finished
6427 * before we got a chance to setup the timer
6429 if (req
->timeout
.head
) {
6430 struct io_timeout_data
*data
= req
->async_data
;
6432 data
->timer
.function
= io_link_timeout_fn
;
6433 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6438 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6440 struct io_ring_ctx
*ctx
= req
->ctx
;
6442 spin_lock_irq(&ctx
->completion_lock
);
6443 __io_queue_linked_timeout(req
);
6444 spin_unlock_irq(&ctx
->completion_lock
);
6446 /* drop submission reference */
6450 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6452 struct io_kiocb
*nxt
= req
->link
;
6454 if (!nxt
|| (req
->flags
& REQ_F_LINK_TIMEOUT
) ||
6455 nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6458 nxt
->timeout
.head
= req
;
6459 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6460 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6464 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
)
6466 struct io_kiocb
*linked_timeout
;
6467 const struct cred
*old_creds
= NULL
;
6471 linked_timeout
= io_prep_linked_timeout(req
);
6473 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
6474 (req
->work
.flags
& IO_WQ_WORK_CREDS
) &&
6475 req
->work
.identity
->creds
!= current_cred()) {
6477 revert_creds(old_creds
);
6478 if (old_creds
== req
->work
.identity
->creds
)
6479 old_creds
= NULL
; /* restored original creds */
6481 old_creds
= override_creds(req
->work
.identity
->creds
);
6484 ret
= io_issue_sqe(req
, true, cs
);
6487 * We async punt it if the file wasn't marked NOWAIT, or if the file
6488 * doesn't support non-blocking read/write attempts
6490 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6491 if (!io_arm_poll_handler(req
)) {
6493 * Queued up for async execution, worker will release
6494 * submit reference when the iocb is actually submitted.
6496 io_queue_async_work(req
);
6500 io_queue_linked_timeout(linked_timeout
);
6501 } else if (likely(!ret
)) {
6502 /* drop submission reference */
6503 req
= io_put_req_find_next(req
);
6505 io_queue_linked_timeout(linked_timeout
);
6508 if (!(req
->flags
& REQ_F_FORCE_ASYNC
))
6510 io_queue_async_work(req
);
6513 /* un-prep timeout, so it'll be killed as any other linked */
6514 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6515 req_set_fail_links(req
);
6517 io_req_complete(req
, ret
);
6521 revert_creds(old_creds
);
6524 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6525 struct io_comp_state
*cs
)
6529 ret
= io_req_defer(req
, sqe
);
6531 if (ret
!= -EIOCBQUEUED
) {
6533 req_set_fail_links(req
);
6535 io_req_complete(req
, ret
);
6537 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6538 if (!req
->async_data
) {
6539 ret
= io_req_defer_prep(req
, sqe
);
6543 io_queue_async_work(req
);
6546 ret
= io_req_prep(req
, sqe
);
6550 __io_queue_sqe(req
, cs
);
6554 static inline void io_queue_link_head(struct io_kiocb
*req
,
6555 struct io_comp_state
*cs
)
6557 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6559 io_req_complete(req
, -ECANCELED
);
6561 io_queue_sqe(req
, NULL
, cs
);
6564 struct io_submit_link
{
6565 struct io_kiocb
*head
;
6566 struct io_kiocb
*last
;
6569 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6570 struct io_submit_link
*link
, struct io_comp_state
*cs
)
6572 struct io_ring_ctx
*ctx
= req
->ctx
;
6576 * If we already have a head request, queue this one for async
6577 * submittal once the head completes. If we don't have a head but
6578 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6579 * submitted sync once the chain is complete. If none of those
6580 * conditions are true (normal request), then just queue it.
6583 struct io_kiocb
*head
= link
->head
;
6586 * Taking sequential execution of a link, draining both sides
6587 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6588 * requests in the link. So, it drains the head and the
6589 * next after the link request. The last one is done via
6590 * drain_next flag to persist the effect across calls.
6592 if (req
->flags
& REQ_F_IO_DRAIN
) {
6593 head
->flags
|= REQ_F_IO_DRAIN
;
6594 ctx
->drain_next
= 1;
6596 ret
= io_req_defer_prep(req
, sqe
);
6597 if (unlikely(ret
)) {
6598 /* fail even hard links since we don't submit */
6599 head
->flags
|= REQ_F_FAIL_LINK
;
6602 trace_io_uring_link(ctx
, req
, head
);
6603 link
->last
->link
= req
;
6606 /* last request of a link, enqueue the link */
6607 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6608 io_queue_link_head(head
, cs
);
6612 if (unlikely(ctx
->drain_next
)) {
6613 req
->flags
|= REQ_F_IO_DRAIN
;
6614 ctx
->drain_next
= 0;
6616 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6617 ret
= io_req_defer_prep(req
, sqe
);
6619 req
->flags
|= REQ_F_FAIL_LINK
;
6623 io_queue_sqe(req
, sqe
, cs
);
6631 * Batched submission is done, ensure local IO is flushed out.
6633 static void io_submit_state_end(struct io_submit_state
*state
)
6635 if (!list_empty(&state
->comp
.list
))
6636 io_submit_flush_completions(&state
->comp
);
6637 if (state
->plug_started
)
6638 blk_finish_plug(&state
->plug
);
6639 io_state_file_put(state
);
6640 if (state
->free_reqs
)
6641 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
6645 * Start submission side cache.
6647 static void io_submit_state_start(struct io_submit_state
*state
,
6648 struct io_ring_ctx
*ctx
, unsigned int max_ios
)
6650 state
->plug_started
= false;
6652 INIT_LIST_HEAD(&state
->comp
.list
);
6653 state
->comp
.ctx
= ctx
;
6654 state
->free_reqs
= 0;
6655 state
->file_refs
= 0;
6656 state
->ios_left
= max_ios
;
6659 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6661 struct io_rings
*rings
= ctx
->rings
;
6664 * Ensure any loads from the SQEs are done at this point,
6665 * since once we write the new head, the application could
6666 * write new data to them.
6668 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6672 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6673 * that is mapped by userspace. This means that care needs to be taken to
6674 * ensure that reads are stable, as we cannot rely on userspace always
6675 * being a good citizen. If members of the sqe are validated and then later
6676 * used, it's important that those reads are done through READ_ONCE() to
6677 * prevent a re-load down the line.
6679 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6681 u32
*sq_array
= ctx
->sq_array
;
6685 * The cached sq head (or cq tail) serves two purposes:
6687 * 1) allows us to batch the cost of updating the user visible
6689 * 2) allows the kernel side to track the head on its own, even
6690 * though the application is the one updating it.
6692 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
6693 if (likely(head
< ctx
->sq_entries
))
6694 return &ctx
->sq_sqes
[head
];
6696 /* drop invalid entries */
6697 ctx
->cached_sq_dropped
++;
6698 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6702 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
6704 ctx
->cached_sq_head
++;
6708 * Check SQE restrictions (opcode and flags).
6710 * Returns 'true' if SQE is allowed, 'false' otherwise.
6712 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6713 struct io_kiocb
*req
,
6714 unsigned int sqe_flags
)
6716 if (!ctx
->restricted
)
6719 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6722 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6723 ctx
->restrictions
.sqe_flags_required
)
6726 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6727 ctx
->restrictions
.sqe_flags_required
))
6733 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6734 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6735 IOSQE_BUFFER_SELECT)
6737 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6738 const struct io_uring_sqe
*sqe
,
6739 struct io_submit_state
*state
)
6741 unsigned int sqe_flags
;
6744 req
->opcode
= READ_ONCE(sqe
->opcode
);
6745 req
->user_data
= READ_ONCE(sqe
->user_data
);
6746 req
->async_data
= NULL
;
6751 req
->fixed_file_refs
= NULL
;
6752 /* one is dropped after submission, the other at completion */
6753 refcount_set(&req
->refs
, 2);
6754 req
->task
= current
;
6757 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6760 if (unlikely(io_sq_thread_acquire_mm_files(ctx
, req
)))
6763 sqe_flags
= READ_ONCE(sqe
->flags
);
6764 /* enforce forwards compatibility on users */
6765 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6768 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6771 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6772 !io_op_defs
[req
->opcode
].buffer_select
)
6775 id
= READ_ONCE(sqe
->personality
);
6777 struct io_identity
*iod
;
6779 iod
= idr_find(&ctx
->personality_idr
, id
);
6782 refcount_inc(&iod
->count
);
6784 __io_req_init_async(req
);
6785 get_cred(iod
->creds
);
6786 req
->work
.identity
= iod
;
6787 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
6790 /* same numerical values with corresponding REQ_F_*, safe to copy */
6791 req
->flags
|= sqe_flags
;
6794 * Plug now if we have more than 1 IO left after this, and the target
6795 * is potentially a read/write to block based storage.
6797 if (!state
->plug_started
&& state
->ios_left
> 1 &&
6798 io_op_defs
[req
->opcode
].plug
) {
6799 blk_start_plug(&state
->plug
);
6800 state
->plug_started
= true;
6804 if (io_op_defs
[req
->opcode
].needs_file
) {
6805 bool fixed
= req
->flags
& REQ_F_FIXED_FILE
;
6807 req
->file
= io_file_get(state
, req
, READ_ONCE(sqe
->fd
), fixed
);
6808 if (unlikely(!req
->file
&&
6809 !io_op_defs
[req
->opcode
].needs_file_no_error
))
6817 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6819 struct io_submit_state state
;
6820 struct io_submit_link link
;
6821 int i
, submitted
= 0;
6823 /* if we have a backlog and couldn't flush it all, return BUSY */
6824 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6825 if (!io_cqring_overflow_flush(ctx
, false, NULL
, NULL
))
6829 /* make sure SQ entry isn't read before tail */
6830 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6832 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6835 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6836 refcount_add(nr
, ¤t
->usage
);
6838 io_submit_state_start(&state
, ctx
, nr
);
6841 for (i
= 0; i
< nr
; i
++) {
6842 const struct io_uring_sqe
*sqe
;
6843 struct io_kiocb
*req
;
6846 sqe
= io_get_sqe(ctx
);
6847 if (unlikely(!sqe
)) {
6848 io_consume_sqe(ctx
);
6851 req
= io_alloc_req(ctx
, &state
);
6852 if (unlikely(!req
)) {
6854 submitted
= -EAGAIN
;
6857 io_consume_sqe(ctx
);
6858 /* will complete beyond this point, count as submitted */
6861 err
= io_init_req(ctx
, req
, sqe
, &state
);
6862 if (unlikely(err
)) {
6865 io_req_complete(req
, err
);
6869 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6870 true, io_async_submit(ctx
));
6871 err
= io_submit_sqe(req
, sqe
, &link
, &state
.comp
);
6876 if (unlikely(submitted
!= nr
)) {
6877 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6878 struct io_uring_task
*tctx
= current
->io_uring
;
6879 int unused
= nr
- ref_used
;
6881 percpu_ref_put_many(&ctx
->refs
, unused
);
6882 percpu_counter_sub(&tctx
->inflight
, unused
);
6883 put_task_struct_many(current
, unused
);
6886 io_queue_link_head(link
.head
, &state
.comp
);
6887 io_submit_state_end(&state
);
6889 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6890 io_commit_sqring(ctx
);
6895 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6897 /* Tell userspace we may need a wakeup call */
6898 spin_lock_irq(&ctx
->completion_lock
);
6899 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6900 spin_unlock_irq(&ctx
->completion_lock
);
6903 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6905 spin_lock_irq(&ctx
->completion_lock
);
6906 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6907 spin_unlock_irq(&ctx
->completion_lock
);
6910 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
6912 unsigned int to_submit
;
6915 to_submit
= io_sqring_entries(ctx
);
6916 /* if we're handling multiple rings, cap submit size for fairness */
6917 if (cap_entries
&& to_submit
> 8)
6920 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
6921 unsigned nr_events
= 0;
6923 mutex_lock(&ctx
->uring_lock
);
6924 if (!list_empty(&ctx
->iopoll_list
))
6925 io_do_iopoll(ctx
, &nr_events
, 0);
6927 if (to_submit
&& likely(!percpu_ref_is_dying(&ctx
->refs
)))
6928 ret
= io_submit_sqes(ctx
, to_submit
);
6929 mutex_unlock(&ctx
->uring_lock
);
6932 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
6933 wake_up(&ctx
->sqo_sq_wait
);
6938 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
6940 struct io_ring_ctx
*ctx
;
6941 unsigned sq_thread_idle
= 0;
6943 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6944 if (sq_thread_idle
< ctx
->sq_thread_idle
)
6945 sq_thread_idle
= ctx
->sq_thread_idle
;
6948 sqd
->sq_thread_idle
= sq_thread_idle
;
6951 static void io_sqd_init_new(struct io_sq_data
*sqd
)
6953 struct io_ring_ctx
*ctx
;
6955 while (!list_empty(&sqd
->ctx_new_list
)) {
6956 ctx
= list_first_entry(&sqd
->ctx_new_list
, struct io_ring_ctx
, sqd_list
);
6957 list_move_tail(&ctx
->sqd_list
, &sqd
->ctx_list
);
6958 complete(&ctx
->sq_thread_comp
);
6961 io_sqd_update_thread_idle(sqd
);
6964 static int io_sq_thread(void *data
)
6966 struct cgroup_subsys_state
*cur_css
= NULL
;
6967 struct files_struct
*old_files
= current
->files
;
6968 struct nsproxy
*old_nsproxy
= current
->nsproxy
;
6969 const struct cred
*old_cred
= NULL
;
6970 struct io_sq_data
*sqd
= data
;
6971 struct io_ring_ctx
*ctx
;
6972 unsigned long timeout
= 0;
6976 current
->files
= NULL
;
6977 current
->nsproxy
= NULL
;
6978 task_unlock(current
);
6980 while (!kthread_should_stop()) {
6982 bool cap_entries
, sqt_spin
, needs_sched
;
6985 * Any changes to the sqd lists are synchronized through the
6986 * kthread parking. This synchronizes the thread vs users,
6987 * the users are synchronized on the sqd->ctx_lock.
6989 if (kthread_should_park()) {
6992 * When sq thread is unparked, in case the previous park operation
6993 * comes from io_put_sq_data(), which means that sq thread is going
6994 * to be stopped, so here needs to have a check.
6996 if (kthread_should_stop())
7000 if (unlikely(!list_empty(&sqd
->ctx_new_list
))) {
7001 io_sqd_init_new(sqd
);
7002 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7006 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
7007 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7008 if (current
->cred
!= ctx
->creds
) {
7010 revert_creds(old_cred
);
7011 old_cred
= override_creds(ctx
->creds
);
7013 io_sq_thread_associate_blkcg(ctx
, &cur_css
);
7015 current
->loginuid
= ctx
->loginuid
;
7016 current
->sessionid
= ctx
->sessionid
;
7019 ret
= __io_sq_thread(ctx
, cap_entries
);
7020 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
7023 io_sq_thread_drop_mm_files();
7026 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
7030 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7034 if (kthread_should_park())
7038 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
7039 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7040 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
7041 !list_empty_careful(&ctx
->iopoll_list
)) {
7042 needs_sched
= false;
7045 if (io_sqring_entries(ctx
)) {
7046 needs_sched
= false;
7052 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7053 io_ring_set_wakeup_flag(ctx
);
7056 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7057 io_ring_clear_wakeup_flag(ctx
);
7060 finish_wait(&sqd
->wait
, &wait
);
7061 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7067 io_sq_thread_unassociate_blkcg();
7069 revert_creds(old_cred
);
7072 current
->files
= old_files
;
7073 current
->nsproxy
= old_nsproxy
;
7074 task_unlock(current
);
7081 struct io_wait_queue
{
7082 struct wait_queue_entry wq
;
7083 struct io_ring_ctx
*ctx
;
7085 unsigned nr_timeouts
;
7088 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
7090 struct io_ring_ctx
*ctx
= iowq
->ctx
;
7093 * Wake up if we have enough events, or if a timeout occurred since we
7094 * started waiting. For timeouts, we always want to return to userspace,
7095 * regardless of event count.
7097 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
7098 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
7101 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
7102 int wake_flags
, void *key
)
7104 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
7107 /* use noflush == true, as we can't safely rely on locking context */
7108 if (!io_should_wake(iowq
, true))
7111 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
7114 static int io_run_task_work_sig(void)
7116 if (io_run_task_work())
7118 if (!signal_pending(current
))
7120 if (test_tsk_thread_flag(current
, TIF_NOTIFY_SIGNAL
))
7121 return -ERESTARTSYS
;
7126 * Wait until events become available, if we don't already have some. The
7127 * application must reap them itself, as they reside on the shared cq ring.
7129 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
7130 const sigset_t __user
*sig
, size_t sigsz
,
7131 struct __kernel_timespec __user
*uts
)
7133 struct io_wait_queue iowq
= {
7136 .func
= io_wake_function
,
7137 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
7140 .to_wait
= min_events
,
7142 struct io_rings
*rings
= ctx
->rings
;
7143 struct timespec64 ts
;
7144 signed long timeout
= 0;
7148 if (io_cqring_events(ctx
, false) >= min_events
)
7150 if (!io_run_task_work())
7155 #ifdef CONFIG_COMPAT
7156 if (in_compat_syscall())
7157 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
7161 ret
= set_user_sigmask(sig
, sigsz
);
7168 if (get_timespec64(&ts
, uts
))
7170 timeout
= timespec64_to_jiffies(&ts
);
7173 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
7174 trace_io_uring_cqring_wait(ctx
, min_events
);
7176 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
7177 TASK_INTERRUPTIBLE
);
7178 /* make sure we run task_work before checking for signals */
7179 ret
= io_run_task_work_sig();
7184 if (io_should_wake(&iowq
, false))
7187 timeout
= schedule_timeout(timeout
);
7196 finish_wait(&ctx
->wait
, &iowq
.wq
);
7198 restore_saved_sigmask_unless(ret
== -EINTR
);
7200 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7203 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7205 #if defined(CONFIG_UNIX)
7206 if (ctx
->ring_sock
) {
7207 struct sock
*sock
= ctx
->ring_sock
->sk
;
7208 struct sk_buff
*skb
;
7210 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7216 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7219 file
= io_file_from_index(ctx
, i
);
7226 static void io_file_ref_kill(struct percpu_ref
*ref
)
7228 struct fixed_file_data
*data
;
7230 data
= container_of(ref
, struct fixed_file_data
, refs
);
7231 complete(&data
->done
);
7234 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7236 struct fixed_file_data
*data
= ctx
->file_data
;
7237 struct fixed_file_ref_node
*ref_node
= NULL
;
7238 unsigned nr_tables
, i
;
7243 spin_lock_bh(&data
->lock
);
7244 ref_node
= data
->node
;
7245 spin_unlock_bh(&data
->lock
);
7247 percpu_ref_kill(&ref_node
->refs
);
7249 percpu_ref_kill(&data
->refs
);
7251 /* wait for all refs nodes to complete */
7252 flush_delayed_work(&ctx
->file_put_work
);
7253 wait_for_completion(&data
->done
);
7255 __io_sqe_files_unregister(ctx
);
7256 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
7257 for (i
= 0; i
< nr_tables
; i
++)
7258 kfree(data
->table
[i
].files
);
7260 percpu_ref_exit(&data
->refs
);
7262 ctx
->file_data
= NULL
;
7263 ctx
->nr_user_files
= 0;
7267 static void io_put_sq_data(struct io_sq_data
*sqd
)
7269 if (refcount_dec_and_test(&sqd
->refs
)) {
7271 * The park is a bit of a work-around, without it we get
7272 * warning spews on shutdown with SQPOLL set and affinity
7273 * set to a single CPU.
7276 kthread_park(sqd
->thread
);
7277 kthread_stop(sqd
->thread
);
7284 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7286 struct io_ring_ctx
*ctx_attach
;
7287 struct io_sq_data
*sqd
;
7290 f
= fdget(p
->wq_fd
);
7292 return ERR_PTR(-ENXIO
);
7293 if (f
.file
->f_op
!= &io_uring_fops
) {
7295 return ERR_PTR(-EINVAL
);
7298 ctx_attach
= f
.file
->private_data
;
7299 sqd
= ctx_attach
->sq_data
;
7302 return ERR_PTR(-EINVAL
);
7305 refcount_inc(&sqd
->refs
);
7310 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
)
7312 struct io_sq_data
*sqd
;
7314 if (p
->flags
& IORING_SETUP_ATTACH_WQ
)
7315 return io_attach_sq_data(p
);
7317 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7319 return ERR_PTR(-ENOMEM
);
7321 refcount_set(&sqd
->refs
, 1);
7322 INIT_LIST_HEAD(&sqd
->ctx_list
);
7323 INIT_LIST_HEAD(&sqd
->ctx_new_list
);
7324 mutex_init(&sqd
->ctx_lock
);
7325 mutex_init(&sqd
->lock
);
7326 init_waitqueue_head(&sqd
->wait
);
7330 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7331 __releases(&sqd
->lock
)
7335 kthread_unpark(sqd
->thread
);
7336 mutex_unlock(&sqd
->lock
);
7339 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7340 __acquires(&sqd
->lock
)
7344 mutex_lock(&sqd
->lock
);
7345 kthread_park(sqd
->thread
);
7348 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
7350 struct io_sq_data
*sqd
= ctx
->sq_data
;
7355 * We may arrive here from the error branch in
7356 * io_sq_offload_create() where the kthread is created
7357 * without being waked up, thus wake it up now to make
7358 * sure the wait will complete.
7360 wake_up_process(sqd
->thread
);
7361 wait_for_completion(&ctx
->sq_thread_comp
);
7363 io_sq_thread_park(sqd
);
7366 mutex_lock(&sqd
->ctx_lock
);
7367 list_del(&ctx
->sqd_list
);
7368 io_sqd_update_thread_idle(sqd
);
7369 mutex_unlock(&sqd
->ctx_lock
);
7372 io_sq_thread_unpark(sqd
);
7374 io_put_sq_data(sqd
);
7375 ctx
->sq_data
= NULL
;
7379 static void io_finish_async(struct io_ring_ctx
*ctx
)
7381 io_sq_thread_stop(ctx
);
7384 io_wq_destroy(ctx
->io_wq
);
7389 #if defined(CONFIG_UNIX)
7391 * Ensure the UNIX gc is aware of our file set, so we are certain that
7392 * the io_uring can be safely unregistered on process exit, even if we have
7393 * loops in the file referencing.
7395 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7397 struct sock
*sk
= ctx
->ring_sock
->sk
;
7398 struct scm_fp_list
*fpl
;
7399 struct sk_buff
*skb
;
7402 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7406 skb
= alloc_skb(0, GFP_KERNEL
);
7415 fpl
->user
= get_uid(ctx
->user
);
7416 for (i
= 0; i
< nr
; i
++) {
7417 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7421 fpl
->fp
[nr_files
] = get_file(file
);
7422 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7427 fpl
->max
= SCM_MAX_FD
;
7428 fpl
->count
= nr_files
;
7429 UNIXCB(skb
).fp
= fpl
;
7430 skb
->destructor
= unix_destruct_scm
;
7431 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7432 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7434 for (i
= 0; i
< nr_files
; i
++)
7445 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7446 * causes regular reference counting to break down. We rely on the UNIX
7447 * garbage collection to take care of this problem for us.
7449 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7451 unsigned left
, total
;
7455 left
= ctx
->nr_user_files
;
7457 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7459 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7463 total
+= this_files
;
7469 while (total
< ctx
->nr_user_files
) {
7470 struct file
*file
= io_file_from_index(ctx
, total
);
7480 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7486 static int io_sqe_alloc_file_tables(struct fixed_file_data
*file_data
,
7487 unsigned nr_tables
, unsigned nr_files
)
7491 for (i
= 0; i
< nr_tables
; i
++) {
7492 struct fixed_file_table
*table
= &file_data
->table
[i
];
7493 unsigned this_files
;
7495 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7496 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
7500 nr_files
-= this_files
;
7506 for (i
= 0; i
< nr_tables
; i
++) {
7507 struct fixed_file_table
*table
= &file_data
->table
[i
];
7508 kfree(table
->files
);
7513 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
7515 #if defined(CONFIG_UNIX)
7516 struct sock
*sock
= ctx
->ring_sock
->sk
;
7517 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7518 struct sk_buff
*skb
;
7521 __skb_queue_head_init(&list
);
7524 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7525 * remove this entry and rearrange the file array.
7527 skb
= skb_dequeue(head
);
7529 struct scm_fp_list
*fp
;
7531 fp
= UNIXCB(skb
).fp
;
7532 for (i
= 0; i
< fp
->count
; i
++) {
7535 if (fp
->fp
[i
] != file
)
7538 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7539 left
= fp
->count
- 1 - i
;
7541 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7542 left
* sizeof(struct file
*));
7549 __skb_queue_tail(&list
, skb
);
7559 __skb_queue_tail(&list
, skb
);
7561 skb
= skb_dequeue(head
);
7564 if (skb_peek(&list
)) {
7565 spin_lock_irq(&head
->lock
);
7566 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7567 __skb_queue_tail(head
, skb
);
7568 spin_unlock_irq(&head
->lock
);
7575 struct io_file_put
{
7576 struct list_head list
;
7580 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
7582 struct fixed_file_data
*file_data
= ref_node
->file_data
;
7583 struct io_ring_ctx
*ctx
= file_data
->ctx
;
7584 struct io_file_put
*pfile
, *tmp
;
7586 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
7587 list_del(&pfile
->list
);
7588 io_ring_file_put(ctx
, pfile
->file
);
7592 percpu_ref_exit(&ref_node
->refs
);
7594 percpu_ref_put(&file_data
->refs
);
7597 static void io_file_put_work(struct work_struct
*work
)
7599 struct io_ring_ctx
*ctx
;
7600 struct llist_node
*node
;
7602 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
7603 node
= llist_del_all(&ctx
->file_put_llist
);
7606 struct fixed_file_ref_node
*ref_node
;
7607 struct llist_node
*next
= node
->next
;
7609 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
7610 __io_file_put_work(ref_node
);
7615 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
7617 struct fixed_file_ref_node
*ref_node
;
7618 struct fixed_file_data
*data
;
7619 struct io_ring_ctx
*ctx
;
7620 bool first_add
= false;
7623 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
7624 data
= ref_node
->file_data
;
7627 spin_lock_bh(&data
->lock
);
7628 ref_node
->done
= true;
7630 while (!list_empty(&data
->ref_list
)) {
7631 ref_node
= list_first_entry(&data
->ref_list
,
7632 struct fixed_file_ref_node
, node
);
7633 /* recycle ref nodes in order */
7634 if (!ref_node
->done
)
7636 list_del(&ref_node
->node
);
7637 first_add
|= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
7639 spin_unlock_bh(&data
->lock
);
7641 if (percpu_ref_is_dying(&data
->refs
))
7645 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
7647 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
7650 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
7651 struct io_ring_ctx
*ctx
)
7653 struct fixed_file_ref_node
*ref_node
;
7655 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7657 return ERR_PTR(-ENOMEM
);
7659 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
7662 return ERR_PTR(-ENOMEM
);
7664 INIT_LIST_HEAD(&ref_node
->node
);
7665 INIT_LIST_HEAD(&ref_node
->file_list
);
7666 ref_node
->file_data
= ctx
->file_data
;
7667 ref_node
->done
= false;
7671 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
7673 percpu_ref_exit(&ref_node
->refs
);
7677 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7680 __s32 __user
*fds
= (__s32 __user
*) arg
;
7681 unsigned nr_tables
, i
;
7683 int fd
, ret
= -ENOMEM
;
7684 struct fixed_file_ref_node
*ref_node
;
7685 struct fixed_file_data
*file_data
;
7691 if (nr_args
> IORING_MAX_FIXED_FILES
)
7694 file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
7697 file_data
->ctx
= ctx
;
7698 init_completion(&file_data
->done
);
7699 INIT_LIST_HEAD(&file_data
->ref_list
);
7700 spin_lock_init(&file_data
->lock
);
7702 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7703 file_data
->table
= kcalloc(nr_tables
, sizeof(*file_data
->table
),
7705 if (!file_data
->table
)
7708 if (percpu_ref_init(&file_data
->refs
, io_file_ref_kill
,
7709 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
7712 if (io_sqe_alloc_file_tables(file_data
, nr_tables
, nr_args
))
7714 ctx
->file_data
= file_data
;
7716 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7717 struct fixed_file_table
*table
;
7720 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7724 /* allow sparse sets */
7734 * Don't allow io_uring instances to be registered. If UNIX
7735 * isn't enabled, then this causes a reference cycle and this
7736 * instance can never get freed. If UNIX is enabled we'll
7737 * handle it just fine, but there's still no point in allowing
7738 * a ring fd as it doesn't support regular read/write anyway.
7740 if (file
->f_op
== &io_uring_fops
) {
7744 table
= &file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7745 index
= i
& IORING_FILE_TABLE_MASK
;
7746 table
->files
[index
] = file
;
7749 ret
= io_sqe_files_scm(ctx
);
7751 io_sqe_files_unregister(ctx
);
7755 ref_node
= alloc_fixed_file_ref_node(ctx
);
7756 if (IS_ERR(ref_node
)) {
7757 io_sqe_files_unregister(ctx
);
7758 return PTR_ERR(ref_node
);
7761 file_data
->node
= ref_node
;
7762 spin_lock_bh(&file_data
->lock
);
7763 list_add_tail(&ref_node
->node
, &file_data
->ref_list
);
7764 spin_unlock_bh(&file_data
->lock
);
7765 percpu_ref_get(&file_data
->refs
);
7768 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7769 file
= io_file_from_index(ctx
, i
);
7773 for (i
= 0; i
< nr_tables
; i
++)
7774 kfree(file_data
->table
[i
].files
);
7775 ctx
->nr_user_files
= 0;
7777 percpu_ref_exit(&file_data
->refs
);
7779 kfree(file_data
->table
);
7781 ctx
->file_data
= NULL
;
7785 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7788 #if defined(CONFIG_UNIX)
7789 struct sock
*sock
= ctx
->ring_sock
->sk
;
7790 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7791 struct sk_buff
*skb
;
7794 * See if we can merge this file into an existing skb SCM_RIGHTS
7795 * file set. If there's no room, fall back to allocating a new skb
7796 * and filling it in.
7798 spin_lock_irq(&head
->lock
);
7799 skb
= skb_peek(head
);
7801 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7803 if (fpl
->count
< SCM_MAX_FD
) {
7804 __skb_unlink(skb
, head
);
7805 spin_unlock_irq(&head
->lock
);
7806 fpl
->fp
[fpl
->count
] = get_file(file
);
7807 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7809 spin_lock_irq(&head
->lock
);
7810 __skb_queue_head(head
, skb
);
7815 spin_unlock_irq(&head
->lock
);
7822 return __io_sqe_files_scm(ctx
, 1, index
);
7828 static int io_queue_file_removal(struct fixed_file_data
*data
,
7831 struct io_file_put
*pfile
;
7832 struct fixed_file_ref_node
*ref_node
= data
->node
;
7834 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
7839 list_add(&pfile
->list
, &ref_node
->file_list
);
7844 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7845 struct io_uring_files_update
*up
,
7848 struct fixed_file_data
*data
= ctx
->file_data
;
7849 struct fixed_file_ref_node
*ref_node
;
7854 bool needs_switch
= false;
7856 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7858 if (done
> ctx
->nr_user_files
)
7861 ref_node
= alloc_fixed_file_ref_node(ctx
);
7862 if (IS_ERR(ref_node
))
7863 return PTR_ERR(ref_node
);
7866 fds
= u64_to_user_ptr(up
->fds
);
7868 struct fixed_file_table
*table
;
7872 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7876 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
7877 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7878 index
= i
& IORING_FILE_TABLE_MASK
;
7879 if (table
->files
[index
]) {
7880 file
= table
->files
[index
];
7881 err
= io_queue_file_removal(data
, file
);
7884 table
->files
[index
] = NULL
;
7885 needs_switch
= true;
7894 * Don't allow io_uring instances to be registered. If
7895 * UNIX isn't enabled, then this causes a reference
7896 * cycle and this instance can never get freed. If UNIX
7897 * is enabled we'll handle it just fine, but there's
7898 * still no point in allowing a ring fd as it doesn't
7899 * support regular read/write anyway.
7901 if (file
->f_op
== &io_uring_fops
) {
7906 table
->files
[index
] = file
;
7907 err
= io_sqe_file_register(ctx
, file
, i
);
7909 table
->files
[index
] = NULL
;
7920 percpu_ref_kill(&data
->node
->refs
);
7921 spin_lock_bh(&data
->lock
);
7922 list_add_tail(&ref_node
->node
, &data
->ref_list
);
7923 data
->node
= ref_node
;
7924 spin_unlock_bh(&data
->lock
);
7925 percpu_ref_get(&ctx
->file_data
->refs
);
7927 destroy_fixed_file_ref_node(ref_node
);
7929 return done
? done
: err
;
7932 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7935 struct io_uring_files_update up
;
7937 if (!ctx
->file_data
)
7941 if (copy_from_user(&up
, arg
, sizeof(up
)))
7946 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7949 static void io_free_work(struct io_wq_work
*work
)
7951 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7953 /* Consider that io_steal_work() relies on this ref */
7957 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
7958 struct io_uring_params
*p
)
7960 struct io_wq_data data
;
7962 struct io_ring_ctx
*ctx_attach
;
7963 unsigned int concurrency
;
7966 data
.user
= ctx
->user
;
7967 data
.free_work
= io_free_work
;
7968 data
.do_work
= io_wq_submit_work
;
7970 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
7971 /* Do QD, or 4 * CPUS, whatever is smallest */
7972 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7974 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
7975 if (IS_ERR(ctx
->io_wq
)) {
7976 ret
= PTR_ERR(ctx
->io_wq
);
7982 f
= fdget(p
->wq_fd
);
7986 if (f
.file
->f_op
!= &io_uring_fops
) {
7991 ctx_attach
= f
.file
->private_data
;
7992 /* @io_wq is protected by holding the fd */
7993 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
7998 ctx
->io_wq
= ctx_attach
->io_wq
;
8004 static int io_uring_alloc_task_context(struct task_struct
*task
)
8006 struct io_uring_task
*tctx
;
8009 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
8010 if (unlikely(!tctx
))
8013 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
8014 if (unlikely(ret
)) {
8020 init_waitqueue_head(&tctx
->wait
);
8022 atomic_set(&tctx
->in_idle
, 0);
8023 tctx
->sqpoll
= false;
8024 io_init_identity(&tctx
->__identity
);
8025 tctx
->identity
= &tctx
->__identity
;
8026 task
->io_uring
= tctx
;
8030 void __io_uring_free(struct task_struct
*tsk
)
8032 struct io_uring_task
*tctx
= tsk
->io_uring
;
8034 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
8035 WARN_ON_ONCE(refcount_read(&tctx
->identity
->count
) != 1);
8036 if (tctx
->identity
!= &tctx
->__identity
)
8037 kfree(tctx
->identity
);
8038 percpu_counter_destroy(&tctx
->inflight
);
8040 tsk
->io_uring
= NULL
;
8043 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
8044 struct io_uring_params
*p
)
8048 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8049 struct io_sq_data
*sqd
;
8052 if (!capable(CAP_SYS_ADMIN
) && !capable(CAP_SYS_NICE
))
8055 sqd
= io_get_sq_data(p
);
8062 io_sq_thread_park(sqd
);
8063 mutex_lock(&sqd
->ctx_lock
);
8064 list_add(&ctx
->sqd_list
, &sqd
->ctx_new_list
);
8065 mutex_unlock(&sqd
->ctx_lock
);
8066 io_sq_thread_unpark(sqd
);
8068 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
8069 if (!ctx
->sq_thread_idle
)
8070 ctx
->sq_thread_idle
= HZ
;
8075 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8076 int cpu
= p
->sq_thread_cpu
;
8079 if (cpu
>= nr_cpu_ids
)
8081 if (!cpu_online(cpu
))
8084 sqd
->thread
= kthread_create_on_cpu(io_sq_thread
, sqd
,
8085 cpu
, "io_uring-sq");
8087 sqd
->thread
= kthread_create(io_sq_thread
, sqd
,
8090 if (IS_ERR(sqd
->thread
)) {
8091 ret
= PTR_ERR(sqd
->thread
);
8095 ret
= io_uring_alloc_task_context(sqd
->thread
);
8098 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8099 /* Can't have SQ_AFF without SQPOLL */
8105 ret
= io_init_wq_offload(ctx
, p
);
8111 io_finish_async(ctx
);
8115 static void io_sq_offload_start(struct io_ring_ctx
*ctx
)
8117 struct io_sq_data
*sqd
= ctx
->sq_data
;
8119 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && sqd
->thread
)
8120 wake_up_process(sqd
->thread
);
8123 static inline void __io_unaccount_mem(struct user_struct
*user
,
8124 unsigned long nr_pages
)
8126 atomic_long_sub(nr_pages
, &user
->locked_vm
);
8129 static inline int __io_account_mem(struct user_struct
*user
,
8130 unsigned long nr_pages
)
8132 unsigned long page_limit
, cur_pages
, new_pages
;
8134 /* Don't allow more pages than we can safely lock */
8135 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
8138 cur_pages
= atomic_long_read(&user
->locked_vm
);
8139 new_pages
= cur_pages
+ nr_pages
;
8140 if (new_pages
> page_limit
)
8142 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
8143 new_pages
) != cur_pages
);
8148 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
8149 enum io_mem_account acct
)
8152 __io_unaccount_mem(ctx
->user
, nr_pages
);
8154 if (ctx
->mm_account
) {
8155 if (acct
== ACCT_LOCKED
) {
8156 mmap_write_lock(ctx
->mm_account
);
8157 ctx
->mm_account
->locked_vm
-= nr_pages
;
8158 mmap_write_unlock(ctx
->mm_account
);
8159 }else if (acct
== ACCT_PINNED
) {
8160 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8165 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
8166 enum io_mem_account acct
)
8170 if (ctx
->limit_mem
) {
8171 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8176 if (ctx
->mm_account
) {
8177 if (acct
== ACCT_LOCKED
) {
8178 mmap_write_lock(ctx
->mm_account
);
8179 ctx
->mm_account
->locked_vm
+= nr_pages
;
8180 mmap_write_unlock(ctx
->mm_account
);
8181 } else if (acct
== ACCT_PINNED
) {
8182 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8189 static void io_mem_free(void *ptr
)
8196 page
= virt_to_head_page(ptr
);
8197 if (put_page_testzero(page
))
8198 free_compound_page(page
);
8201 static void *io_mem_alloc(size_t size
)
8203 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8206 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8209 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8212 struct io_rings
*rings
;
8213 size_t off
, sq_array_size
;
8215 off
= struct_size(rings
, cqes
, cq_entries
);
8216 if (off
== SIZE_MAX
)
8220 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8228 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8229 if (sq_array_size
== SIZE_MAX
)
8232 if (check_add_overflow(off
, sq_array_size
, &off
))
8238 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
8242 pages
= (size_t)1 << get_order(
8243 rings_size(sq_entries
, cq_entries
, NULL
));
8244 pages
+= (size_t)1 << get_order(
8245 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
8250 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
8254 if (!ctx
->user_bufs
)
8257 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8258 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8260 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
8261 unpin_user_page(imu
->bvec
[j
].bv_page
);
8263 if (imu
->acct_pages
)
8264 io_unaccount_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8269 kfree(ctx
->user_bufs
);
8270 ctx
->user_bufs
= NULL
;
8271 ctx
->nr_user_bufs
= 0;
8275 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8276 void __user
*arg
, unsigned index
)
8278 struct iovec __user
*src
;
8280 #ifdef CONFIG_COMPAT
8282 struct compat_iovec __user
*ciovs
;
8283 struct compat_iovec ciov
;
8285 ciovs
= (struct compat_iovec __user
*) arg
;
8286 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8289 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8290 dst
->iov_len
= ciov
.iov_len
;
8294 src
= (struct iovec __user
*) arg
;
8295 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8301 * Not super efficient, but this is just a registration time. And we do cache
8302 * the last compound head, so generally we'll only do a full search if we don't
8305 * We check if the given compound head page has already been accounted, to
8306 * avoid double accounting it. This allows us to account the full size of the
8307 * page, not just the constituent pages of a huge page.
8309 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8310 int nr_pages
, struct page
*hpage
)
8314 /* check current page array */
8315 for (i
= 0; i
< nr_pages
; i
++) {
8316 if (!PageCompound(pages
[i
]))
8318 if (compound_head(pages
[i
]) == hpage
)
8322 /* check previously registered pages */
8323 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8324 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8326 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8327 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8329 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8337 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8338 int nr_pages
, struct io_mapped_ubuf
*imu
,
8339 struct page
**last_hpage
)
8343 for (i
= 0; i
< nr_pages
; i
++) {
8344 if (!PageCompound(pages
[i
])) {
8349 hpage
= compound_head(pages
[i
]);
8350 if (hpage
== *last_hpage
)
8352 *last_hpage
= hpage
;
8353 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8355 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8359 if (!imu
->acct_pages
)
8362 ret
= io_account_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8364 imu
->acct_pages
= 0;
8368 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8371 struct vm_area_struct
**vmas
= NULL
;
8372 struct page
**pages
= NULL
;
8373 struct page
*last_hpage
= NULL
;
8374 int i
, j
, got_pages
= 0;
8379 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8382 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
8384 if (!ctx
->user_bufs
)
8387 for (i
= 0; i
< nr_args
; i
++) {
8388 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8389 unsigned long off
, start
, end
, ubuf
;
8394 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8399 * Don't impose further limits on the size and buffer
8400 * constraints here, we'll -EINVAL later when IO is
8401 * submitted if they are wrong.
8404 if (!iov
.iov_base
|| !iov
.iov_len
)
8407 /* arbitrary limit, but we need something */
8408 if (iov
.iov_len
> SZ_1G
)
8411 ubuf
= (unsigned long) iov
.iov_base
;
8412 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8413 start
= ubuf
>> PAGE_SHIFT
;
8414 nr_pages
= end
- start
;
8417 if (!pages
|| nr_pages
> got_pages
) {
8420 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
8422 vmas
= kvmalloc_array(nr_pages
,
8423 sizeof(struct vm_area_struct
*),
8425 if (!pages
|| !vmas
) {
8429 got_pages
= nr_pages
;
8432 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8439 mmap_read_lock(current
->mm
);
8440 pret
= pin_user_pages(ubuf
, nr_pages
,
8441 FOLL_WRITE
| FOLL_LONGTERM
,
8443 if (pret
== nr_pages
) {
8444 /* don't support file backed memory */
8445 for (j
= 0; j
< nr_pages
; j
++) {
8446 struct vm_area_struct
*vma
= vmas
[j
];
8449 !is_file_hugepages(vma
->vm_file
)) {
8455 ret
= pret
< 0 ? pret
: -EFAULT
;
8457 mmap_read_unlock(current
->mm
);
8460 * if we did partial map, or found file backed vmas,
8461 * release any pages we did get
8464 unpin_user_pages(pages
, pret
);
8469 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, &last_hpage
);
8471 unpin_user_pages(pages
, pret
);
8476 off
= ubuf
& ~PAGE_MASK
;
8478 for (j
= 0; j
< nr_pages
; j
++) {
8481 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8482 imu
->bvec
[j
].bv_page
= pages
[j
];
8483 imu
->bvec
[j
].bv_len
= vec_len
;
8484 imu
->bvec
[j
].bv_offset
= off
;
8488 /* store original address for later verification */
8490 imu
->len
= iov
.iov_len
;
8491 imu
->nr_bvecs
= nr_pages
;
8493 ctx
->nr_user_bufs
++;
8501 io_sqe_buffer_unregister(ctx
);
8505 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8507 __s32 __user
*fds
= arg
;
8513 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8516 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8517 if (IS_ERR(ctx
->cq_ev_fd
)) {
8518 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8519 ctx
->cq_ev_fd
= NULL
;
8526 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8528 if (ctx
->cq_ev_fd
) {
8529 eventfd_ctx_put(ctx
->cq_ev_fd
);
8530 ctx
->cq_ev_fd
= NULL
;
8537 static int __io_destroy_buffers(int id
, void *p
, void *data
)
8539 struct io_ring_ctx
*ctx
= data
;
8540 struct io_buffer
*buf
= p
;
8542 __io_remove_buffers(ctx
, buf
, id
, -1U);
8546 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8548 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
8549 idr_destroy(&ctx
->io_buffer_idr
);
8552 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8554 io_finish_async(ctx
);
8555 io_sqe_buffer_unregister(ctx
);
8557 if (ctx
->sqo_task
) {
8558 put_task_struct(ctx
->sqo_task
);
8559 ctx
->sqo_task
= NULL
;
8560 mmdrop(ctx
->mm_account
);
8561 ctx
->mm_account
= NULL
;
8564 #ifdef CONFIG_BLK_CGROUP
8565 if (ctx
->sqo_blkcg_css
)
8566 css_put(ctx
->sqo_blkcg_css
);
8569 io_sqe_files_unregister(ctx
);
8570 io_eventfd_unregister(ctx
);
8571 io_destroy_buffers(ctx
);
8572 idr_destroy(&ctx
->personality_idr
);
8574 #if defined(CONFIG_UNIX)
8575 if (ctx
->ring_sock
) {
8576 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8577 sock_release(ctx
->ring_sock
);
8581 io_mem_free(ctx
->rings
);
8582 io_mem_free(ctx
->sq_sqes
);
8584 percpu_ref_exit(&ctx
->refs
);
8585 free_uid(ctx
->user
);
8586 put_cred(ctx
->creds
);
8587 kfree(ctx
->cancel_hash
);
8588 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
8592 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8594 struct io_ring_ctx
*ctx
= file
->private_data
;
8597 poll_wait(file
, &ctx
->cq_wait
, wait
);
8599 * synchronizes with barrier from wq_has_sleeper call in
8603 if (!io_sqring_full(ctx
))
8604 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8605 if (io_cqring_events(ctx
, false))
8606 mask
|= EPOLLIN
| EPOLLRDNORM
;
8611 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8613 struct io_ring_ctx
*ctx
= file
->private_data
;
8615 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8618 static int io_remove_personalities(int id
, void *p
, void *data
)
8620 struct io_ring_ctx
*ctx
= data
;
8621 struct io_identity
*iod
;
8623 iod
= idr_remove(&ctx
->personality_idr
, id
);
8625 put_cred(iod
->creds
);
8626 if (refcount_dec_and_test(&iod
->count
))
8632 static void io_ring_exit_work(struct work_struct
*work
)
8634 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
8638 * If we're doing polled IO and end up having requests being
8639 * submitted async (out-of-line), then completions can come in while
8640 * we're waiting for refs to drop. We need to reap these manually,
8641 * as nobody else will be looking for them.
8644 io_iopoll_try_reap_events(ctx
);
8645 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8646 io_ring_ctx_free(ctx
);
8649 static bool io_cancel_ctx_cb(struct io_wq_work
*work
, void *data
)
8651 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8653 return req
->ctx
== data
;
8656 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8658 mutex_lock(&ctx
->uring_lock
);
8659 percpu_ref_kill(&ctx
->refs
);
8660 /* if force is set, the ring is going away. always drop after that */
8661 ctx
->cq_overflow_flushed
= 1;
8663 io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8664 mutex_unlock(&ctx
->uring_lock
);
8666 io_kill_timeouts(ctx
, NULL
, NULL
);
8667 io_poll_remove_all(ctx
, NULL
, NULL
);
8670 io_wq_cancel_cb(ctx
->io_wq
, io_cancel_ctx_cb
, ctx
, true);
8672 /* if we failed setting up the ctx, we might not have any rings */
8673 io_iopoll_try_reap_events(ctx
);
8674 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
8677 * Do this upfront, so we won't have a grace period where the ring
8678 * is closed but resources aren't reaped yet. This can cause
8679 * spurious failure in setting up a new ring.
8681 io_unaccount_mem(ctx
, ring_pages(ctx
->sq_entries
, ctx
->cq_entries
),
8684 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8686 * Use system_unbound_wq to avoid spawning tons of event kworkers
8687 * if we're exiting a ton of rings at the same time. It just adds
8688 * noise and overhead, there's no discernable change in runtime
8689 * over using system_wq.
8691 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8694 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8696 struct io_ring_ctx
*ctx
= file
->private_data
;
8698 file
->private_data
= NULL
;
8699 io_ring_ctx_wait_and_kill(ctx
);
8703 struct io_task_cancel
{
8704 struct task_struct
*task
;
8705 struct files_struct
*files
;
8708 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8710 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8711 struct io_task_cancel
*cancel
= data
;
8714 if (cancel
->files
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
8715 unsigned long flags
;
8716 struct io_ring_ctx
*ctx
= req
->ctx
;
8718 /* protect against races with linked timeouts */
8719 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
8720 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8721 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
8723 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8728 static void io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8729 struct task_struct
*task
,
8730 struct files_struct
*files
)
8732 struct io_defer_entry
*de
= NULL
;
8735 spin_lock_irq(&ctx
->completion_lock
);
8736 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8737 if (io_match_task(de
->req
, task
, files
)) {
8738 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8742 spin_unlock_irq(&ctx
->completion_lock
);
8744 while (!list_empty(&list
)) {
8745 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8746 list_del_init(&de
->list
);
8747 req_set_fail_links(de
->req
);
8748 io_put_req(de
->req
);
8749 io_req_complete(de
->req
, -ECANCELED
);
8754 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8755 struct task_struct
*task
,
8756 struct files_struct
*files
)
8758 while (!list_empty_careful(&ctx
->inflight_list
)) {
8759 struct io_task_cancel cancel
= { .task
= task
, .files
= files
};
8760 struct io_kiocb
*req
;
8764 spin_lock_irq(&ctx
->inflight_lock
);
8765 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
8766 if (req
->task
!= task
||
8767 req
->work
.identity
->files
!= files
)
8773 prepare_to_wait(&task
->io_uring
->wait
, &wait
,
8774 TASK_UNINTERRUPTIBLE
);
8775 spin_unlock_irq(&ctx
->inflight_lock
);
8777 /* We need to keep going until we don't find a matching req */
8781 io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, &cancel
, true);
8782 io_poll_remove_all(ctx
, task
, files
);
8783 io_kill_timeouts(ctx
, task
, files
);
8784 /* cancellations _may_ trigger task work */
8787 finish_wait(&task
->io_uring
->wait
, &wait
);
8791 static void __io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8792 struct task_struct
*task
)
8795 struct io_task_cancel cancel
= { .task
= task
, .files
= NULL
, };
8796 enum io_wq_cancel cret
;
8799 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, &cancel
, true);
8800 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8803 /* SQPOLL thread does its own polling */
8804 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8805 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8806 io_iopoll_try_reap_events(ctx
);
8811 ret
|= io_poll_remove_all(ctx
, task
, NULL
);
8812 ret
|= io_kill_timeouts(ctx
, task
, NULL
);
8813 ret
|= io_run_task_work();
8821 * We need to iteratively cancel requests, in case a request has dependent
8822 * hard links. These persist even for failure of cancelations, hence keep
8823 * looping until none are found.
8825 static void io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8826 struct files_struct
*files
)
8828 struct task_struct
*task
= current
;
8830 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
) {
8831 task
= ctx
->sq_data
->thread
;
8832 atomic_inc(&task
->io_uring
->in_idle
);
8833 io_sq_thread_park(ctx
->sq_data
);
8836 io_cancel_defer_files(ctx
, task
, files
);
8837 io_ring_submit_lock(ctx
, (ctx
->flags
& IORING_SETUP_IOPOLL
));
8838 io_cqring_overflow_flush(ctx
, true, task
, files
);
8839 io_ring_submit_unlock(ctx
, (ctx
->flags
& IORING_SETUP_IOPOLL
));
8842 __io_uring_cancel_task_requests(ctx
, task
);
8844 io_uring_cancel_files(ctx
, task
, files
);
8846 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
) {
8847 atomic_dec(&task
->io_uring
->in_idle
);
8849 * If the files that are going away are the ones in the thread
8850 * identity, clear them out.
8852 if (task
->io_uring
->identity
->files
== files
)
8853 task
->io_uring
->identity
->files
= NULL
;
8854 io_sq_thread_unpark(ctx
->sq_data
);
8859 * Note that this task has used io_uring. We use it for cancelation purposes.
8861 static int io_uring_add_task_file(struct io_ring_ctx
*ctx
, struct file
*file
)
8863 struct io_uring_task
*tctx
= current
->io_uring
;
8866 if (unlikely(!tctx
)) {
8867 ret
= io_uring_alloc_task_context(current
);
8870 tctx
= current
->io_uring
;
8872 if (tctx
->last
!= file
) {
8873 void *old
= xa_load(&tctx
->xa
, (unsigned long)file
);
8877 ret
= xa_err(xa_store(&tctx
->xa
, (unsigned long)file
,
8888 * This is race safe in that the task itself is doing this, hence it
8889 * cannot be going through the exit/cancel paths at the same time.
8890 * This cannot be modified while exit/cancel is running.
8892 if (!tctx
->sqpoll
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
8893 tctx
->sqpoll
= true;
8899 * Remove this io_uring_file -> task mapping.
8901 static void io_uring_del_task_file(struct file
*file
)
8903 struct io_uring_task
*tctx
= current
->io_uring
;
8905 if (tctx
->last
== file
)
8907 file
= xa_erase(&tctx
->xa
, (unsigned long)file
);
8913 * Drop task note for this file if we're the only ones that hold it after
8916 static void io_uring_attempt_task_drop(struct file
*file
)
8918 if (!current
->io_uring
)
8921 * fput() is pending, will be 2 if the only other ref is our potential
8922 * task file note. If the task is exiting, drop regardless of count.
8924 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
) ||
8925 atomic_long_read(&file
->f_count
) == 2)
8926 io_uring_del_task_file(file
);
8929 void __io_uring_files_cancel(struct files_struct
*files
)
8931 struct io_uring_task
*tctx
= current
->io_uring
;
8933 unsigned long index
;
8935 /* make sure overflow events are dropped */
8936 atomic_inc(&tctx
->in_idle
);
8938 xa_for_each(&tctx
->xa
, index
, file
) {
8939 struct io_ring_ctx
*ctx
= file
->private_data
;
8941 io_uring_cancel_task_requests(ctx
, files
);
8943 io_uring_del_task_file(file
);
8946 atomic_dec(&tctx
->in_idle
);
8949 static s64
tctx_inflight(struct io_uring_task
*tctx
)
8951 unsigned long index
;
8955 inflight
= percpu_counter_sum(&tctx
->inflight
);
8960 * If we have SQPOLL rings, then we need to iterate and find them, and
8961 * add the pending count for those.
8963 xa_for_each(&tctx
->xa
, index
, file
) {
8964 struct io_ring_ctx
*ctx
= file
->private_data
;
8966 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8967 struct io_uring_task
*__tctx
= ctx
->sqo_task
->io_uring
;
8969 inflight
+= percpu_counter_sum(&__tctx
->inflight
);
8977 * Find any io_uring fd that this task has registered or done IO on, and cancel
8980 void __io_uring_task_cancel(void)
8982 struct io_uring_task
*tctx
= current
->io_uring
;
8986 /* make sure overflow events are dropped */
8987 atomic_inc(&tctx
->in_idle
);
8990 /* read completions before cancelations */
8991 inflight
= tctx_inflight(tctx
);
8994 __io_uring_files_cancel(NULL
);
8996 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
8999 * If we've seen completions, retry. This avoids a race where
9000 * a completion comes in before we did prepare_to_wait().
9002 if (inflight
!= tctx_inflight(tctx
))
9005 finish_wait(&tctx
->wait
, &wait
);
9008 atomic_dec(&tctx
->in_idle
);
9011 static int io_uring_flush(struct file
*file
, void *data
)
9013 io_uring_attempt_task_drop(file
);
9017 static void *io_uring_validate_mmap_request(struct file
*file
,
9018 loff_t pgoff
, size_t sz
)
9020 struct io_ring_ctx
*ctx
= file
->private_data
;
9021 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9026 case IORING_OFF_SQ_RING
:
9027 case IORING_OFF_CQ_RING
:
9030 case IORING_OFF_SQES
:
9034 return ERR_PTR(-EINVAL
);
9037 page
= virt_to_head_page(ptr
);
9038 if (sz
> page_size(page
))
9039 return ERR_PTR(-EINVAL
);
9046 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9048 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9052 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9054 return PTR_ERR(ptr
);
9056 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9057 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9060 #else /* !CONFIG_MMU */
9062 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9064 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9067 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9069 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9072 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9073 unsigned long addr
, unsigned long len
,
9074 unsigned long pgoff
, unsigned long flags
)
9078 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9080 return PTR_ERR(ptr
);
9082 return (unsigned long) ptr
;
9085 #endif /* !CONFIG_MMU */
9087 static void io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9092 if (!io_sqring_full(ctx
))
9095 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9097 if (!io_sqring_full(ctx
))
9101 } while (!signal_pending(current
));
9103 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9106 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9107 struct __kernel_timespec __user
**ts
,
9108 const sigset_t __user
**sig
)
9110 struct io_uring_getevents_arg arg
;
9113 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9114 * is just a pointer to the sigset_t.
9116 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9117 *sig
= (const sigset_t __user
*) argp
;
9123 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9124 * timespec and sigset_t pointers if good.
9126 if (*argsz
!= sizeof(arg
))
9128 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9130 *sig
= u64_to_user_ptr(arg
.sigmask
);
9131 *argsz
= arg
.sigmask_sz
;
9132 *ts
= u64_to_user_ptr(arg
.ts
);
9136 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9137 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9140 struct io_ring_ctx
*ctx
;
9147 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9148 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
))
9156 if (f
.file
->f_op
!= &io_uring_fops
)
9160 ctx
= f
.file
->private_data
;
9161 if (!percpu_ref_tryget(&ctx
->refs
))
9165 if (ctx
->flags
& IORING_SETUP_R_DISABLED
)
9169 * For SQ polling, the thread will do all submissions and completions.
9170 * Just return the requested submit count, and wake the thread if
9174 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9175 if (!list_empty_careful(&ctx
->cq_overflow_list
)) {
9176 bool needs_lock
= ctx
->flags
& IORING_SETUP_IOPOLL
;
9178 io_ring_submit_lock(ctx
, needs_lock
);
9179 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
9180 io_ring_submit_unlock(ctx
, needs_lock
);
9182 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9183 wake_up(&ctx
->sq_data
->wait
);
9184 if (flags
& IORING_ENTER_SQ_WAIT
)
9185 io_sqpoll_wait_sq(ctx
);
9186 submitted
= to_submit
;
9187 } else if (to_submit
) {
9188 ret
= io_uring_add_task_file(ctx
, f
.file
);
9191 mutex_lock(&ctx
->uring_lock
);
9192 submitted
= io_submit_sqes(ctx
, to_submit
);
9193 mutex_unlock(&ctx
->uring_lock
);
9195 if (submitted
!= to_submit
)
9198 if (flags
& IORING_ENTER_GETEVENTS
) {
9199 const sigset_t __user
*sig
;
9200 struct __kernel_timespec __user
*ts
;
9202 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
9206 min_complete
= min(min_complete
, ctx
->cq_entries
);
9209 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9210 * space applications don't need to do io completion events
9211 * polling again, they can rely on io_sq_thread to do polling
9212 * work, which can reduce cpu usage and uring_lock contention.
9214 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
9215 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9216 ret
= io_iopoll_check(ctx
, min_complete
);
9218 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
9223 percpu_ref_put(&ctx
->refs
);
9226 return submitted
? submitted
: ret
;
9229 #ifdef CONFIG_PROC_FS
9230 static int io_uring_show_cred(int id
, void *p
, void *data
)
9232 struct io_identity
*iod
= p
;
9233 const struct cred
*cred
= iod
->creds
;
9234 struct seq_file
*m
= data
;
9235 struct user_namespace
*uns
= seq_user_ns(m
);
9236 struct group_info
*gi
;
9241 seq_printf(m
, "%5d\n", id
);
9242 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
9243 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
9244 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
9245 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
9246 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
9247 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
9248 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
9249 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
9250 seq_puts(m
, "\n\tGroups:\t");
9251 gi
= cred
->group_info
;
9252 for (g
= 0; g
< gi
->ngroups
; g
++) {
9253 seq_put_decimal_ull(m
, g
? " " : "",
9254 from_kgid_munged(uns
, gi
->gid
[g
]));
9256 seq_puts(m
, "\n\tCapEff:\t");
9257 cap
= cred
->cap_effective
;
9258 CAP_FOR_EACH_U32(__capi
)
9259 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
9264 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
9266 struct io_sq_data
*sq
= NULL
;
9271 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9272 * since fdinfo case grabs it in the opposite direction of normal use
9273 * cases. If we fail to get the lock, we just don't iterate any
9274 * structures that could be going away outside the io_uring mutex.
9276 has_lock
= mutex_trylock(&ctx
->uring_lock
);
9278 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
9281 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
9282 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
9283 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
9284 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
9285 struct fixed_file_table
*table
;
9288 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
9289 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
9291 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
9293 seq_printf(m
, "%5u: <none>\n", i
);
9295 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
9296 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
9297 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
9299 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
9300 (unsigned int) buf
->len
);
9302 if (has_lock
&& !idr_is_empty(&ctx
->personality_idr
)) {
9303 seq_printf(m
, "Personalities:\n");
9304 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
9306 seq_printf(m
, "PollList:\n");
9307 spin_lock_irq(&ctx
->completion_lock
);
9308 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9309 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9310 struct io_kiocb
*req
;
9312 hlist_for_each_entry(req
, list
, hash_node
)
9313 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9314 req
->task
->task_works
!= NULL
);
9316 spin_unlock_irq(&ctx
->completion_lock
);
9318 mutex_unlock(&ctx
->uring_lock
);
9321 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9323 struct io_ring_ctx
*ctx
= f
->private_data
;
9325 if (percpu_ref_tryget(&ctx
->refs
)) {
9326 __io_uring_show_fdinfo(ctx
, m
);
9327 percpu_ref_put(&ctx
->refs
);
9332 static const struct file_operations io_uring_fops
= {
9333 .release
= io_uring_release
,
9334 .flush
= io_uring_flush
,
9335 .mmap
= io_uring_mmap
,
9337 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9338 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9340 .poll
= io_uring_poll
,
9341 .fasync
= io_uring_fasync
,
9342 #ifdef CONFIG_PROC_FS
9343 .show_fdinfo
= io_uring_show_fdinfo
,
9347 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9348 struct io_uring_params
*p
)
9350 struct io_rings
*rings
;
9351 size_t size
, sq_array_offset
;
9353 /* make sure these are sane, as we already accounted them */
9354 ctx
->sq_entries
= p
->sq_entries
;
9355 ctx
->cq_entries
= p
->cq_entries
;
9357 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9358 if (size
== SIZE_MAX
)
9361 rings
= io_mem_alloc(size
);
9366 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9367 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9368 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9369 rings
->sq_ring_entries
= p
->sq_entries
;
9370 rings
->cq_ring_entries
= p
->cq_entries
;
9371 ctx
->sq_mask
= rings
->sq_ring_mask
;
9372 ctx
->cq_mask
= rings
->cq_ring_mask
;
9374 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9375 if (size
== SIZE_MAX
) {
9376 io_mem_free(ctx
->rings
);
9381 ctx
->sq_sqes
= io_mem_alloc(size
);
9382 if (!ctx
->sq_sqes
) {
9383 io_mem_free(ctx
->rings
);
9391 static int io_uring_install_fd(struct io_ring_ctx
*ctx
, struct file
*file
)
9395 fd
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9399 ret
= io_uring_add_task_file(ctx
, file
);
9404 fd_install(fd
, file
);
9409 * Allocate an anonymous fd, this is what constitutes the application
9410 * visible backing of an io_uring instance. The application mmaps this
9411 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9412 * we have to tie this fd to a socket for file garbage collection purposes.
9414 static struct file
*io_uring_get_file(struct io_ring_ctx
*ctx
)
9417 #if defined(CONFIG_UNIX)
9420 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9423 return ERR_PTR(ret
);
9426 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9427 O_RDWR
| O_CLOEXEC
);
9428 #if defined(CONFIG_UNIX)
9430 sock_release(ctx
->ring_sock
);
9431 ctx
->ring_sock
= NULL
;
9433 ctx
->ring_sock
->file
= file
;
9439 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9440 struct io_uring_params __user
*params
)
9442 struct user_struct
*user
= NULL
;
9443 struct io_ring_ctx
*ctx
;
9450 if (entries
> IORING_MAX_ENTRIES
) {
9451 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9453 entries
= IORING_MAX_ENTRIES
;
9457 * Use twice as many entries for the CQ ring. It's possible for the
9458 * application to drive a higher depth than the size of the SQ ring,
9459 * since the sqes are only used at submission time. This allows for
9460 * some flexibility in overcommitting a bit. If the application has
9461 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9462 * of CQ ring entries manually.
9464 p
->sq_entries
= roundup_pow_of_two(entries
);
9465 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9467 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9468 * to a power-of-two, if it isn't already. We do NOT impose
9469 * any cq vs sq ring sizing.
9473 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9474 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9476 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9478 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9479 if (p
->cq_entries
< p
->sq_entries
)
9482 p
->cq_entries
= 2 * p
->sq_entries
;
9485 user
= get_uid(current_user());
9486 limit_mem
= !capable(CAP_IPC_LOCK
);
9489 ret
= __io_account_mem(user
,
9490 ring_pages(p
->sq_entries
, p
->cq_entries
));
9497 ctx
= io_ring_ctx_alloc(p
);
9500 __io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
9505 ctx
->compat
= in_compat_syscall();
9507 ctx
->creds
= get_current_cred();
9509 ctx
->loginuid
= current
->loginuid
;
9510 ctx
->sessionid
= current
->sessionid
;
9512 ctx
->sqo_task
= get_task_struct(current
);
9515 * This is just grabbed for accounting purposes. When a process exits,
9516 * the mm is exited and dropped before the files, hence we need to hang
9517 * on to this mm purely for the purposes of being able to unaccount
9518 * memory (locked/pinned vm). It's not used for anything else.
9520 mmgrab(current
->mm
);
9521 ctx
->mm_account
= current
->mm
;
9523 #ifdef CONFIG_BLK_CGROUP
9525 * The sq thread will belong to the original cgroup it was inited in.
9526 * If the cgroup goes offline (e.g. disabling the io controller), then
9527 * issued bios will be associated with the closest cgroup later in the
9531 ctx
->sqo_blkcg_css
= blkcg_css();
9532 ret
= css_tryget_online(ctx
->sqo_blkcg_css
);
9535 /* don't init against a dying cgroup, have the user try again */
9536 ctx
->sqo_blkcg_css
= NULL
;
9543 * Account memory _before_ installing the file descriptor. Once
9544 * the descriptor is installed, it can get closed at any time. Also
9545 * do this before hitting the general error path, as ring freeing
9546 * will un-account as well.
9548 io_account_mem(ctx
, ring_pages(p
->sq_entries
, p
->cq_entries
),
9550 ctx
->limit_mem
= limit_mem
;
9552 ret
= io_allocate_scq_urings(ctx
, p
);
9556 ret
= io_sq_offload_create(ctx
, p
);
9560 if (!(p
->flags
& IORING_SETUP_R_DISABLED
))
9561 io_sq_offload_start(ctx
);
9563 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9564 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9565 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9566 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9567 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9568 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9569 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9570 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9572 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9573 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9574 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9575 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9576 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9577 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9578 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9579 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9581 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9582 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9583 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9584 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
9585 IORING_FEAT_EXT_ARG
;
9587 if (copy_to_user(params
, p
, sizeof(*p
))) {
9592 file
= io_uring_get_file(ctx
);
9594 ret
= PTR_ERR(file
);
9599 * Install ring fd as the very last thing, so we don't risk someone
9600 * having closed it before we finish setup
9602 ret
= io_uring_install_fd(ctx
, file
);
9604 /* fput will clean it up */
9609 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9612 io_ring_ctx_wait_and_kill(ctx
);
9617 * Sets up an aio uring context, and returns the fd. Applications asks for a
9618 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9619 * params structure passed in.
9621 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9623 struct io_uring_params p
;
9626 if (copy_from_user(&p
, params
, sizeof(p
)))
9628 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9633 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9634 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9635 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9636 IORING_SETUP_R_DISABLED
))
9639 return io_uring_create(entries
, &p
, params
);
9642 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9643 struct io_uring_params __user
*, params
)
9645 return io_uring_setup(entries
, params
);
9648 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9650 struct io_uring_probe
*p
;
9654 size
= struct_size(p
, ops
, nr_args
);
9655 if (size
== SIZE_MAX
)
9657 p
= kzalloc(size
, GFP_KERNEL
);
9662 if (copy_from_user(p
, arg
, size
))
9665 if (memchr_inv(p
, 0, size
))
9668 p
->last_op
= IORING_OP_LAST
- 1;
9669 if (nr_args
> IORING_OP_LAST
)
9670 nr_args
= IORING_OP_LAST
;
9672 for (i
= 0; i
< nr_args
; i
++) {
9674 if (!io_op_defs
[i
].not_supported
)
9675 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9680 if (copy_to_user(arg
, p
, size
))
9687 static int io_register_personality(struct io_ring_ctx
*ctx
)
9689 struct io_identity
*id
;
9692 id
= kmalloc(sizeof(*id
), GFP_KERNEL
);
9696 io_init_identity(id
);
9697 id
->creds
= get_current_cred();
9699 ret
= idr_alloc_cyclic(&ctx
->personality_idr
, id
, 1, USHRT_MAX
, GFP_KERNEL
);
9701 put_cred(id
->creds
);
9707 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
9709 struct io_identity
*iod
;
9711 iod
= idr_remove(&ctx
->personality_idr
, id
);
9713 put_cred(iod
->creds
);
9714 if (refcount_dec_and_test(&iod
->count
))
9722 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9723 unsigned int nr_args
)
9725 struct io_uring_restriction
*res
;
9729 /* Restrictions allowed only if rings started disabled */
9730 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9733 /* We allow only a single restrictions registration */
9734 if (ctx
->restrictions
.registered
)
9737 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9740 size
= array_size(nr_args
, sizeof(*res
));
9741 if (size
== SIZE_MAX
)
9744 res
= memdup_user(arg
, size
);
9746 return PTR_ERR(res
);
9750 for (i
= 0; i
< nr_args
; i
++) {
9751 switch (res
[i
].opcode
) {
9752 case IORING_RESTRICTION_REGISTER_OP
:
9753 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9758 __set_bit(res
[i
].register_op
,
9759 ctx
->restrictions
.register_op
);
9761 case IORING_RESTRICTION_SQE_OP
:
9762 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9767 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9769 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9770 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9772 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9773 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9782 /* Reset all restrictions if an error happened */
9784 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9786 ctx
->restrictions
.registered
= true;
9792 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9794 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9797 if (ctx
->restrictions
.registered
)
9798 ctx
->restricted
= 1;
9800 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9802 io_sq_offload_start(ctx
);
9807 static bool io_register_op_must_quiesce(int op
)
9810 case IORING_UNREGISTER_FILES
:
9811 case IORING_REGISTER_FILES_UPDATE
:
9812 case IORING_REGISTER_PROBE
:
9813 case IORING_REGISTER_PERSONALITY
:
9814 case IORING_UNREGISTER_PERSONALITY
:
9821 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
9822 void __user
*arg
, unsigned nr_args
)
9823 __releases(ctx
->uring_lock
)
9824 __acquires(ctx
->uring_lock
)
9829 * We're inside the ring mutex, if the ref is already dying, then
9830 * someone else killed the ctx or is already going through
9831 * io_uring_register().
9833 if (percpu_ref_is_dying(&ctx
->refs
))
9836 if (io_register_op_must_quiesce(opcode
)) {
9837 percpu_ref_kill(&ctx
->refs
);
9840 * Drop uring mutex before waiting for references to exit. If
9841 * another thread is currently inside io_uring_enter() it might
9842 * need to grab the uring_lock to make progress. If we hold it
9843 * here across the drain wait, then we can deadlock. It's safe
9844 * to drop the mutex here, since no new references will come in
9845 * after we've killed the percpu ref.
9847 mutex_unlock(&ctx
->uring_lock
);
9849 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
9852 ret
= io_run_task_work_sig();
9857 mutex_lock(&ctx
->uring_lock
);
9860 percpu_ref_resurrect(&ctx
->refs
);
9865 if (ctx
->restricted
) {
9866 if (opcode
>= IORING_REGISTER_LAST
) {
9871 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
9878 case IORING_REGISTER_BUFFERS
:
9879 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
9881 case IORING_UNREGISTER_BUFFERS
:
9885 ret
= io_sqe_buffer_unregister(ctx
);
9887 case IORING_REGISTER_FILES
:
9888 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
9890 case IORING_UNREGISTER_FILES
:
9894 ret
= io_sqe_files_unregister(ctx
);
9896 case IORING_REGISTER_FILES_UPDATE
:
9897 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
9899 case IORING_REGISTER_EVENTFD
:
9900 case IORING_REGISTER_EVENTFD_ASYNC
:
9904 ret
= io_eventfd_register(ctx
, arg
);
9907 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
9908 ctx
->eventfd_async
= 1;
9910 ctx
->eventfd_async
= 0;
9912 case IORING_UNREGISTER_EVENTFD
:
9916 ret
= io_eventfd_unregister(ctx
);
9918 case IORING_REGISTER_PROBE
:
9920 if (!arg
|| nr_args
> 256)
9922 ret
= io_probe(ctx
, arg
, nr_args
);
9924 case IORING_REGISTER_PERSONALITY
:
9928 ret
= io_register_personality(ctx
);
9930 case IORING_UNREGISTER_PERSONALITY
:
9934 ret
= io_unregister_personality(ctx
, nr_args
);
9936 case IORING_REGISTER_ENABLE_RINGS
:
9940 ret
= io_register_enable_rings(ctx
);
9942 case IORING_REGISTER_RESTRICTIONS
:
9943 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
9951 if (io_register_op_must_quiesce(opcode
)) {
9952 /* bring the ctx back to life */
9953 percpu_ref_reinit(&ctx
->refs
);
9955 reinit_completion(&ctx
->ref_comp
);
9960 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
9961 void __user
*, arg
, unsigned int, nr_args
)
9963 struct io_ring_ctx
*ctx
;
9972 if (f
.file
->f_op
!= &io_uring_fops
)
9975 ctx
= f
.file
->private_data
;
9977 mutex_lock(&ctx
->uring_lock
);
9978 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
9979 mutex_unlock(&ctx
->uring_lock
);
9980 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
9981 ctx
->cq_ev_fd
!= NULL
, ret
);
9987 static int __init
io_uring_init(void)
9989 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
9990 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
9991 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
9994 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
9995 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
9996 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
9997 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
9998 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
9999 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
10000 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
10001 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
10002 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
10003 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
10004 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
10005 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
10006 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
10007 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
10008 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
10009 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
10010 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
10011 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
10012 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
10013 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
10014 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
10015 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
10016 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
10017 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
10018 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
10019 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
10020 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
10021 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
10022 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
10023 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
10024 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
10026 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
10027 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
10028 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
10031 __initcall(io_uring_init
);