1 // SPDX-License-Identifier: GPL-2.0
3 * Shared application/kernel submission and completion ring pairs, for
4 * supporting fast/efficient IO.
6 * A note on the read/write ordering memory barriers that are matched between
7 * the application and kernel side.
9 * After the application reads the CQ ring tail, it must use an
10 * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
11 * before writing the tail (using smp_load_acquire to read the tail will
12 * do). It also needs a smp_mb() before updating CQ head (ordering the
13 * entry load(s) with the head store), pairing with an implicit barrier
14 * through a control-dependency in io_get_cqring (smp_store_release to
15 * store head will do). Failure to do so could lead to reading invalid
18 * Likewise, the application must use an appropriate smp_wmb() before
19 * writing the SQ tail (ordering SQ entry stores with the tail store),
20 * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
21 * to store the tail will do). And it needs a barrier ordering the SQ
22 * head load before writing new SQ entries (smp_load_acquire to read
25 * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
26 * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
27 * updating the SQ tail; a full memory barrier smp_mb() is needed
30 * Also see the examples in the liburing library:
32 * git://git.kernel.dk/liburing
34 * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
35 * from data shared between the kernel and application. This is done both
36 * for ordering purposes, but also to ensure that once a value is loaded from
37 * data that the application could potentially modify, it remains stable.
39 * Copyright (C) 2018-2019 Jens Axboe
40 * Copyright (c) 2018-2019 Christoph Hellwig
42 #include <linux/kernel.h>
43 #include <linux/init.h>
44 #include <linux/errno.h>
45 #include <linux/syscalls.h>
46 #include <linux/compat.h>
47 #include <net/compat.h>
48 #include <linux/refcount.h>
49 #include <linux/uio.h>
50 #include <linux/bits.h>
52 #include <linux/sched/signal.h>
54 #include <linux/file.h>
55 #include <linux/fdtable.h>
57 #include <linux/mman.h>
58 #include <linux/percpu.h>
59 #include <linux/slab.h>
60 #include <linux/kthread.h>
61 #include <linux/blkdev.h>
62 #include <linux/bvec.h>
63 #include <linux/net.h>
65 #include <net/af_unix.h>
67 #include <linux/anon_inodes.h>
68 #include <linux/sched/mm.h>
69 #include <linux/uaccess.h>
70 #include <linux/nospec.h>
71 #include <linux/sizes.h>
72 #include <linux/hugetlb.h>
73 #include <linux/highmem.h>
74 #include <linux/namei.h>
75 #include <linux/fsnotify.h>
76 #include <linux/fadvise.h>
77 #include <linux/eventpoll.h>
78 #include <linux/fs_struct.h>
79 #include <linux/splice.h>
80 #include <linux/task_work.h>
81 #include <linux/pagemap.h>
82 #include <linux/io_uring.h>
83 #include <linux/blk-cgroup.h>
84 #include <linux/audit.h>
86 #define CREATE_TRACE_POINTS
87 #include <trace/events/io_uring.h>
89 #include <uapi/linux/io_uring.h>
94 #define IORING_MAX_ENTRIES 32768
95 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
98 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
100 #define IORING_FILE_TABLE_SHIFT 9
101 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
102 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
103 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
104 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
105 IORING_REGISTER_LAST + IORING_OP_LAST)
108 u32 head ____cacheline_aligned_in_smp
;
109 u32 tail ____cacheline_aligned_in_smp
;
113 * This data is shared with the application through the mmap at offsets
114 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
116 * The offsets to the member fields are published through struct
117 * io_sqring_offsets when calling io_uring_setup.
121 * Head and tail offsets into the ring; the offsets need to be
122 * masked to get valid indices.
124 * The kernel controls head of the sq ring and the tail of the cq ring,
125 * and the application controls tail of the sq ring and the head of the
128 struct io_uring sq
, cq
;
130 * Bitmasks to apply to head and tail offsets (constant, equals
133 u32 sq_ring_mask
, cq_ring_mask
;
134 /* Ring sizes (constant, power of 2) */
135 u32 sq_ring_entries
, cq_ring_entries
;
137 * Number of invalid entries dropped by the kernel due to
138 * invalid index stored in array
140 * Written by the kernel, shouldn't be modified by the
141 * application (i.e. get number of "new events" by comparing to
144 * After a new SQ head value was read by the application this
145 * counter includes all submissions that were dropped reaching
146 * the new SQ head (and possibly more).
152 * Written by the kernel, shouldn't be modified by the
155 * The application needs a full memory barrier before checking
156 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
162 * Written by the application, shouldn't be modified by the
167 * Number of completion events lost because the queue was full;
168 * this should be avoided by the application by making sure
169 * there are not more requests pending than there is space in
170 * the completion queue.
172 * Written by the kernel, shouldn't be modified by the
173 * application (i.e. get number of "new events" by comparing to
176 * As completion events come in out of order this counter is not
177 * ordered with any other data.
181 * Ring buffer of completion events.
183 * The kernel writes completion events fresh every time they are
184 * produced, so the application is allowed to modify pending
187 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
190 struct io_mapped_ubuf
{
193 struct bio_vec
*bvec
;
194 unsigned int nr_bvecs
;
195 unsigned long acct_pages
;
198 struct fixed_file_table
{
202 struct fixed_file_ref_node
{
203 struct percpu_ref refs
;
204 struct list_head node
;
205 struct list_head file_list
;
206 struct fixed_file_data
*file_data
;
207 struct llist_node llist
;
210 struct fixed_file_data
{
211 struct fixed_file_table
*table
;
212 struct io_ring_ctx
*ctx
;
214 struct fixed_file_ref_node
*node
;
215 struct percpu_ref refs
;
216 struct completion done
;
217 struct list_head ref_list
;
222 struct list_head list
;
228 struct io_restriction
{
229 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
230 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
231 u8 sqe_flags_allowed
;
232 u8 sqe_flags_required
;
240 /* ctx's that are using this sqd */
241 struct list_head ctx_list
;
242 struct list_head ctx_new_list
;
243 struct mutex ctx_lock
;
245 struct task_struct
*thread
;
246 struct wait_queue_head wait
;
251 struct percpu_ref refs
;
252 } ____cacheline_aligned_in_smp
;
256 unsigned int compat
: 1;
257 unsigned int limit_mem
: 1;
258 unsigned int cq_overflow_flushed
: 1;
259 unsigned int drain_next
: 1;
260 unsigned int eventfd_async
: 1;
261 unsigned int restricted
: 1;
264 * Ring buffer of indices into array of io_uring_sqe, which is
265 * mmapped by the application using the IORING_OFF_SQES offset.
267 * This indirection could e.g. be used to assign fixed
268 * io_uring_sqe entries to operations and only submit them to
269 * the queue when needed.
271 * The kernel modifies neither the indices array nor the entries
275 unsigned cached_sq_head
;
278 unsigned sq_thread_idle
;
279 unsigned cached_sq_dropped
;
280 unsigned cached_cq_overflow
;
281 unsigned long sq_check_overflow
;
283 struct list_head defer_list
;
284 struct list_head timeout_list
;
285 struct list_head cq_overflow_list
;
287 wait_queue_head_t inflight_wait
;
288 struct io_uring_sqe
*sq_sqes
;
289 } ____cacheline_aligned_in_smp
;
291 struct io_rings
*rings
;
297 * For SQPOLL usage - we hold a reference to the parent task, so we
298 * have access to the ->files
300 struct task_struct
*sqo_task
;
302 /* Only used for accounting purposes */
303 struct mm_struct
*mm_account
;
305 #ifdef CONFIG_BLK_CGROUP
306 struct cgroup_subsys_state
*sqo_blkcg_css
;
309 struct io_sq_data
*sq_data
; /* if using sq thread polling */
311 struct wait_queue_head sqo_sq_wait
;
312 struct wait_queue_entry sqo_wait_entry
;
313 struct list_head sqd_list
;
316 * If used, fixed file set. Writers must ensure that ->refs is dead,
317 * readers must ensure that ->refs is alive as long as the file* is
318 * used. Only updated through io_uring_register(2).
320 struct fixed_file_data
*file_data
;
321 unsigned nr_user_files
;
323 /* if used, fixed mapped user buffers */
324 unsigned nr_user_bufs
;
325 struct io_mapped_ubuf
*user_bufs
;
327 struct user_struct
*user
;
329 const struct cred
*creds
;
333 unsigned int sessionid
;
336 struct completion ref_comp
;
337 struct completion sq_thread_comp
;
339 /* if all else fails... */
340 struct io_kiocb
*fallback_req
;
342 #if defined(CONFIG_UNIX)
343 struct socket
*ring_sock
;
346 struct idr io_buffer_idr
;
348 struct idr personality_idr
;
351 unsigned cached_cq_tail
;
354 atomic_t cq_timeouts
;
355 unsigned long cq_check_overflow
;
356 struct wait_queue_head cq_wait
;
357 struct fasync_struct
*cq_fasync
;
358 struct eventfd_ctx
*cq_ev_fd
;
359 } ____cacheline_aligned_in_smp
;
362 struct mutex uring_lock
;
363 wait_queue_head_t wait
;
364 } ____cacheline_aligned_in_smp
;
367 spinlock_t completion_lock
;
370 * ->iopoll_list is protected by the ctx->uring_lock for
371 * io_uring instances that don't use IORING_SETUP_SQPOLL.
372 * For SQPOLL, only the single threaded io_sq_thread() will
373 * manipulate the list, hence no extra locking is needed there.
375 struct list_head iopoll_list
;
376 struct hlist_head
*cancel_hash
;
377 unsigned cancel_hash_bits
;
378 bool poll_multi_file
;
380 spinlock_t inflight_lock
;
381 struct list_head inflight_list
;
382 } ____cacheline_aligned_in_smp
;
384 struct delayed_work file_put_work
;
385 struct llist_head file_put_llist
;
387 struct work_struct exit_work
;
388 struct io_restriction restrictions
;
392 * First field must be the file pointer in all the
393 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
395 struct io_poll_iocb
{
398 struct wait_queue_head
*head
;
404 struct wait_queue_entry wait
;
409 struct file
*put_file
;
413 struct io_timeout_data
{
414 struct io_kiocb
*req
;
415 struct hrtimer timer
;
416 struct timespec64 ts
;
417 enum hrtimer_mode mode
;
422 struct sockaddr __user
*addr
;
423 int __user
*addr_len
;
425 unsigned long nofile
;
445 struct list_head list
;
448 struct io_timeout_rem
{
454 /* NOTE: kiocb has the file as the first member, so don't do it here */
462 struct sockaddr __user
*addr
;
469 struct user_msghdr __user
*umsg
;
475 struct io_buffer
*kbuf
;
481 struct filename
*filename
;
483 unsigned long nofile
;
486 struct io_files_update
{
512 struct epoll_event event
;
516 struct file
*file_out
;
517 struct file
*file_in
;
524 struct io_provide_buf
{
538 const char __user
*filename
;
539 struct statx __user
*buffer
;
542 struct io_completion
{
544 struct list_head list
;
548 struct io_async_connect
{
549 struct sockaddr_storage address
;
552 struct io_async_msghdr
{
553 struct iovec fast_iov
[UIO_FASTIOV
];
555 struct sockaddr __user
*uaddr
;
557 struct sockaddr_storage addr
;
561 struct iovec fast_iov
[UIO_FASTIOV
];
562 const struct iovec
*free_iovec
;
563 struct iov_iter iter
;
565 struct wait_page_queue wpq
;
569 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
570 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
571 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
572 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
573 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
574 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
581 REQ_F_LINK_TIMEOUT_BIT
,
583 REQ_F_NEED_CLEANUP_BIT
,
585 REQ_F_BUFFER_SELECTED_BIT
,
586 REQ_F_NO_FILE_TABLE_BIT
,
587 REQ_F_WORK_INITIALIZED_BIT
,
588 REQ_F_LTIMEOUT_ACTIVE_BIT
,
590 /* not a real bit, just to check we're not overflowing the space */
596 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
597 /* drain existing IO first */
598 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
600 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
601 /* doesn't sever on completion < 0 */
602 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
604 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
605 /* IOSQE_BUFFER_SELECT */
606 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
609 REQ_F_LINK_HEAD
= BIT(REQ_F_LINK_HEAD_BIT
),
610 /* fail rest of links */
611 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
612 /* on inflight list */
613 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
614 /* read/write uses file position */
615 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
616 /* must not punt to workers */
617 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
618 /* has or had linked timeout */
619 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
621 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
623 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
624 /* already went through poll handler */
625 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
626 /* buffer already selected */
627 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
628 /* doesn't need file table for this request */
629 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
630 /* io_wq_work is initialized */
631 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
632 /* linked timeout is active, i.e. prepared by link's head */
633 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
637 struct io_poll_iocb poll
;
638 struct io_poll_iocb
*double_poll
;
642 * NOTE! Each of the iocb union members has the file pointer
643 * as the first entry in their struct definition. So you can
644 * access the file pointer through any of the sub-structs,
645 * or directly as just 'ki_filp' in this struct.
651 struct io_poll_iocb poll
;
652 struct io_accept accept
;
654 struct io_cancel cancel
;
655 struct io_timeout timeout
;
656 struct io_timeout_rem timeout_rem
;
657 struct io_connect connect
;
658 struct io_sr_msg sr_msg
;
660 struct io_close close
;
661 struct io_files_update files_update
;
662 struct io_fadvise fadvise
;
663 struct io_madvise madvise
;
664 struct io_epoll epoll
;
665 struct io_splice splice
;
666 struct io_provide_buf pbuf
;
667 struct io_statx statx
;
668 /* use only after cleaning per-op data, see io_clean_op() */
669 struct io_completion
compl;
672 /* opcode allocated if it needs to store data for async defer */
675 /* polled IO has completed */
681 struct io_ring_ctx
*ctx
;
684 struct task_struct
*task
;
687 struct list_head link_list
;
690 * 1. used with ctx->iopoll_list with reads/writes
691 * 2. to track reqs with ->files (see io_op_def::file_table)
693 struct list_head inflight_entry
;
695 struct percpu_ref
*fixed_file_refs
;
696 struct callback_head task_work
;
697 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
698 struct hlist_node hash_node
;
699 struct async_poll
*apoll
;
700 struct io_wq_work work
;
703 struct io_defer_entry
{
704 struct list_head list
;
705 struct io_kiocb
*req
;
709 #define IO_IOPOLL_BATCH 8
711 struct io_comp_state
{
713 struct list_head list
;
714 struct io_ring_ctx
*ctx
;
717 struct io_submit_state
{
718 struct blk_plug plug
;
721 * io_kiocb alloc cache
723 void *reqs
[IO_IOPOLL_BATCH
];
724 unsigned int free_reqs
;
727 * Batch completion logic
729 struct io_comp_state comp
;
732 * File reference cache
736 unsigned int has_refs
;
737 unsigned int ios_left
;
741 /* needs req->file assigned */
742 unsigned needs_file
: 1;
743 /* don't fail if file grab fails */
744 unsigned needs_file_no_error
: 1;
745 /* hash wq insertion if file is a regular file */
746 unsigned hash_reg_file
: 1;
747 /* unbound wq insertion if file is a non-regular file */
748 unsigned unbound_nonreg_file
: 1;
749 /* opcode is not supported by this kernel */
750 unsigned not_supported
: 1;
751 /* set if opcode supports polled "wait" */
753 unsigned pollout
: 1;
754 /* op supports buffer selection */
755 unsigned buffer_select
: 1;
756 /* must always have async data allocated */
757 unsigned needs_async_data
: 1;
758 /* size of async data needed, if any */
759 unsigned short async_size
;
763 static const struct io_op_def io_op_defs
[] = {
764 [IORING_OP_NOP
] = {},
765 [IORING_OP_READV
] = {
767 .unbound_nonreg_file
= 1,
770 .needs_async_data
= 1,
771 .async_size
= sizeof(struct io_async_rw
),
772 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
774 [IORING_OP_WRITEV
] = {
777 .unbound_nonreg_file
= 1,
779 .needs_async_data
= 1,
780 .async_size
= sizeof(struct io_async_rw
),
781 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
784 [IORING_OP_FSYNC
] = {
786 .work_flags
= IO_WQ_WORK_BLKCG
,
788 [IORING_OP_READ_FIXED
] = {
790 .unbound_nonreg_file
= 1,
792 .async_size
= sizeof(struct io_async_rw
),
793 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
795 [IORING_OP_WRITE_FIXED
] = {
798 .unbound_nonreg_file
= 1,
800 .async_size
= sizeof(struct io_async_rw
),
801 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
|
804 [IORING_OP_POLL_ADD
] = {
806 .unbound_nonreg_file
= 1,
808 [IORING_OP_POLL_REMOVE
] = {},
809 [IORING_OP_SYNC_FILE_RANGE
] = {
811 .work_flags
= IO_WQ_WORK_BLKCG
,
813 [IORING_OP_SENDMSG
] = {
815 .unbound_nonreg_file
= 1,
817 .needs_async_data
= 1,
818 .async_size
= sizeof(struct io_async_msghdr
),
819 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
822 [IORING_OP_RECVMSG
] = {
824 .unbound_nonreg_file
= 1,
827 .needs_async_data
= 1,
828 .async_size
= sizeof(struct io_async_msghdr
),
829 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
832 [IORING_OP_TIMEOUT
] = {
833 .needs_async_data
= 1,
834 .async_size
= sizeof(struct io_timeout_data
),
835 .work_flags
= IO_WQ_WORK_MM
,
837 [IORING_OP_TIMEOUT_REMOVE
] = {},
838 [IORING_OP_ACCEPT
] = {
840 .unbound_nonreg_file
= 1,
842 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
,
844 [IORING_OP_ASYNC_CANCEL
] = {},
845 [IORING_OP_LINK_TIMEOUT
] = {
846 .needs_async_data
= 1,
847 .async_size
= sizeof(struct io_timeout_data
),
848 .work_flags
= IO_WQ_WORK_MM
,
850 [IORING_OP_CONNECT
] = {
852 .unbound_nonreg_file
= 1,
854 .needs_async_data
= 1,
855 .async_size
= sizeof(struct io_async_connect
),
856 .work_flags
= IO_WQ_WORK_MM
,
858 [IORING_OP_FALLOCATE
] = {
860 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
,
862 [IORING_OP_OPENAT
] = {
863 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
|
866 [IORING_OP_CLOSE
] = {
868 .needs_file_no_error
= 1,
869 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
,
871 [IORING_OP_FILES_UPDATE
] = {
872 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
,
874 [IORING_OP_STATX
] = {
875 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
|
876 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
880 .unbound_nonreg_file
= 1,
883 .async_size
= sizeof(struct io_async_rw
),
884 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
886 [IORING_OP_WRITE
] = {
888 .unbound_nonreg_file
= 1,
890 .async_size
= sizeof(struct io_async_rw
),
891 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
894 [IORING_OP_FADVISE
] = {
896 .work_flags
= IO_WQ_WORK_BLKCG
,
898 [IORING_OP_MADVISE
] = {
899 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
903 .unbound_nonreg_file
= 1,
905 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
909 .unbound_nonreg_file
= 1,
912 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
914 [IORING_OP_OPENAT2
] = {
915 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_FS
|
918 [IORING_OP_EPOLL_CTL
] = {
919 .unbound_nonreg_file
= 1,
920 .work_flags
= IO_WQ_WORK_FILES
,
922 [IORING_OP_SPLICE
] = {
925 .unbound_nonreg_file
= 1,
926 .work_flags
= IO_WQ_WORK_BLKCG
,
928 [IORING_OP_PROVIDE_BUFFERS
] = {},
929 [IORING_OP_REMOVE_BUFFERS
] = {},
933 .unbound_nonreg_file
= 1,
937 enum io_mem_account
{
942 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
943 struct io_comp_state
*cs
);
944 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
945 static void io_put_req(struct io_kiocb
*req
);
946 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
947 static void io_double_put_req(struct io_kiocb
*req
);
948 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
949 static void __io_queue_linked_timeout(struct io_kiocb
*req
);
950 static void io_queue_linked_timeout(struct io_kiocb
*req
);
951 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
952 struct io_uring_files_update
*ip
,
954 static void __io_clean_op(struct io_kiocb
*req
);
955 static struct file
*io_file_get(struct io_submit_state
*state
,
956 struct io_kiocb
*req
, int fd
, bool fixed
);
957 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
);
958 static void io_file_put_work(struct work_struct
*work
);
960 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
961 struct iovec
**iovec
, struct iov_iter
*iter
,
963 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
964 const struct iovec
*fast_iov
,
965 struct iov_iter
*iter
, bool force
);
967 static struct kmem_cache
*req_cachep
;
969 static const struct file_operations io_uring_fops
;
971 struct sock
*io_uring_get_socket(struct file
*file
)
973 #if defined(CONFIG_UNIX)
974 if (file
->f_op
== &io_uring_fops
) {
975 struct io_ring_ctx
*ctx
= file
->private_data
;
977 return ctx
->ring_sock
->sk
;
982 EXPORT_SYMBOL(io_uring_get_socket
);
984 static inline void io_clean_op(struct io_kiocb
*req
)
986 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
|
991 static void io_sq_thread_drop_mm(void)
993 struct mm_struct
*mm
= current
->mm
;
996 kthread_unuse_mm(mm
);
1001 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
1004 if (unlikely(!(ctx
->flags
& IORING_SETUP_SQPOLL
) ||
1005 !ctx
->sqo_task
->mm
||
1006 !mmget_not_zero(ctx
->sqo_task
->mm
)))
1008 kthread_use_mm(ctx
->sqo_task
->mm
);
1014 static int io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
,
1015 struct io_kiocb
*req
)
1017 if (!(io_op_defs
[req
->opcode
].work_flags
& IO_WQ_WORK_MM
))
1019 return __io_sq_thread_acquire_mm(ctx
);
1022 static void io_sq_thread_associate_blkcg(struct io_ring_ctx
*ctx
,
1023 struct cgroup_subsys_state
**cur_css
)
1026 #ifdef CONFIG_BLK_CGROUP
1027 /* puts the old one when swapping */
1028 if (*cur_css
!= ctx
->sqo_blkcg_css
) {
1029 kthread_associate_blkcg(ctx
->sqo_blkcg_css
);
1030 *cur_css
= ctx
->sqo_blkcg_css
;
1035 static void io_sq_thread_unassociate_blkcg(void)
1037 #ifdef CONFIG_BLK_CGROUP
1038 kthread_associate_blkcg(NULL
);
1042 static inline void req_set_fail_links(struct io_kiocb
*req
)
1044 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1045 req
->flags
|= REQ_F_FAIL_LINK
;
1049 * None of these are dereferenced, they are simply used to check if any of
1050 * them have changed. If we're under current and check they are still the
1051 * same, we're fine to grab references to them for actual out-of-line use.
1053 static void io_init_identity(struct io_identity
*id
)
1055 id
->files
= current
->files
;
1056 id
->mm
= current
->mm
;
1057 #ifdef CONFIG_BLK_CGROUP
1059 id
->blkcg_css
= blkcg_css();
1062 id
->creds
= current_cred();
1063 id
->nsproxy
= current
->nsproxy
;
1064 id
->fs
= current
->fs
;
1065 id
->fsize
= rlimit(RLIMIT_FSIZE
);
1067 id
->loginuid
= current
->loginuid
;
1068 id
->sessionid
= current
->sessionid
;
1070 refcount_set(&id
->count
, 1);
1073 static inline void __io_req_init_async(struct io_kiocb
*req
)
1075 memset(&req
->work
, 0, sizeof(req
->work
));
1076 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1080 * Note: must call io_req_init_async() for the first time you
1081 * touch any members of io_wq_work.
1083 static inline void io_req_init_async(struct io_kiocb
*req
)
1085 struct io_uring_task
*tctx
= current
->io_uring
;
1087 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1090 __io_req_init_async(req
);
1092 /* Grab a ref if this isn't our static identity */
1093 req
->work
.identity
= tctx
->identity
;
1094 if (tctx
->identity
!= &tctx
->__identity
)
1095 refcount_inc(&req
->work
.identity
->count
);
1098 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
1100 return ctx
->flags
& IORING_SETUP_SQPOLL
;
1103 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1105 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1107 complete(&ctx
->ref_comp
);
1110 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1112 return !req
->timeout
.off
;
1115 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1117 struct io_ring_ctx
*ctx
;
1120 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1124 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
1125 if (!ctx
->fallback_req
)
1129 * Use 5 bits less than the max cq entries, that should give us around
1130 * 32 entries per hash list if totally full and uniformly spread.
1132 hash_bits
= ilog2(p
->cq_entries
);
1136 ctx
->cancel_hash_bits
= hash_bits
;
1137 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1139 if (!ctx
->cancel_hash
)
1141 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1143 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1144 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1147 ctx
->flags
= p
->flags
;
1148 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1149 INIT_LIST_HEAD(&ctx
->sqd_list
);
1150 init_waitqueue_head(&ctx
->cq_wait
);
1151 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1152 init_completion(&ctx
->ref_comp
);
1153 init_completion(&ctx
->sq_thread_comp
);
1154 idr_init(&ctx
->io_buffer_idr
);
1155 idr_init(&ctx
->personality_idr
);
1156 mutex_init(&ctx
->uring_lock
);
1157 init_waitqueue_head(&ctx
->wait
);
1158 spin_lock_init(&ctx
->completion_lock
);
1159 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1160 INIT_LIST_HEAD(&ctx
->defer_list
);
1161 INIT_LIST_HEAD(&ctx
->timeout_list
);
1162 init_waitqueue_head(&ctx
->inflight_wait
);
1163 spin_lock_init(&ctx
->inflight_lock
);
1164 INIT_LIST_HEAD(&ctx
->inflight_list
);
1165 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
1166 init_llist_head(&ctx
->file_put_llist
);
1169 if (ctx
->fallback_req
)
1170 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
1171 kfree(ctx
->cancel_hash
);
1176 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1178 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1179 struct io_ring_ctx
*ctx
= req
->ctx
;
1181 return seq
!= ctx
->cached_cq_tail
1182 + READ_ONCE(ctx
->cached_cq_overflow
);
1188 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1190 struct io_rings
*rings
= ctx
->rings
;
1192 /* order cqe stores with ring update */
1193 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1195 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1196 wake_up_interruptible(&ctx
->cq_wait
);
1197 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1201 static void io_put_identity(struct io_uring_task
*tctx
, struct io_kiocb
*req
)
1203 if (req
->work
.identity
== &tctx
->__identity
)
1205 if (refcount_dec_and_test(&req
->work
.identity
->count
))
1206 kfree(req
->work
.identity
);
1209 static void io_req_clean_work(struct io_kiocb
*req
)
1211 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1214 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1216 if (req
->work
.flags
& IO_WQ_WORK_MM
) {
1217 mmdrop(req
->work
.identity
->mm
);
1218 req
->work
.flags
&= ~IO_WQ_WORK_MM
;
1220 #ifdef CONFIG_BLK_CGROUP
1221 if (req
->work
.flags
& IO_WQ_WORK_BLKCG
) {
1222 css_put(req
->work
.identity
->blkcg_css
);
1223 req
->work
.flags
&= ~IO_WQ_WORK_BLKCG
;
1226 if (req
->work
.flags
& IO_WQ_WORK_CREDS
) {
1227 put_cred(req
->work
.identity
->creds
);
1228 req
->work
.flags
&= ~IO_WQ_WORK_CREDS
;
1230 if (req
->work
.flags
& IO_WQ_WORK_FS
) {
1231 struct fs_struct
*fs
= req
->work
.identity
->fs
;
1233 spin_lock(&req
->work
.identity
->fs
->lock
);
1236 spin_unlock(&req
->work
.identity
->fs
->lock
);
1239 req
->work
.flags
&= ~IO_WQ_WORK_FS
;
1242 io_put_identity(req
->task
->io_uring
, req
);
1246 * Create a private copy of io_identity, since some fields don't match
1247 * the current context.
1249 static bool io_identity_cow(struct io_kiocb
*req
)
1251 struct io_uring_task
*tctx
= current
->io_uring
;
1252 const struct cred
*creds
= NULL
;
1253 struct io_identity
*id
;
1255 if (req
->work
.flags
& IO_WQ_WORK_CREDS
)
1256 creds
= req
->work
.identity
->creds
;
1258 id
= kmemdup(req
->work
.identity
, sizeof(*id
), GFP_KERNEL
);
1259 if (unlikely(!id
)) {
1260 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1265 * We can safely just re-init the creds we copied Either the field
1266 * matches the current one, or we haven't grabbed it yet. The only
1267 * exception is ->creds, through registered personalities, so handle
1268 * that one separately.
1270 io_init_identity(id
);
1272 req
->work
.identity
->creds
= creds
;
1274 /* add one for this request */
1275 refcount_inc(&id
->count
);
1277 /* drop old identity, assign new one. one ref for req, one for tctx */
1278 if (req
->work
.identity
!= tctx
->identity
&&
1279 refcount_sub_and_test(2, &req
->work
.identity
->count
))
1280 kfree(req
->work
.identity
);
1282 req
->work
.identity
= id
;
1283 tctx
->identity
= id
;
1287 static bool io_grab_identity(struct io_kiocb
*req
)
1289 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1290 struct io_identity
*id
= req
->work
.identity
;
1291 struct io_ring_ctx
*ctx
= req
->ctx
;
1293 if (def
->work_flags
& IO_WQ_WORK_FSIZE
) {
1294 if (id
->fsize
!= rlimit(RLIMIT_FSIZE
))
1296 req
->work
.flags
|= IO_WQ_WORK_FSIZE
;
1299 if (!(req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1300 (def
->work_flags
& IO_WQ_WORK_FILES
) &&
1301 !(req
->flags
& REQ_F_NO_FILE_TABLE
)) {
1302 if (id
->files
!= current
->files
||
1303 id
->nsproxy
!= current
->nsproxy
)
1305 atomic_inc(&id
->files
->count
);
1306 get_nsproxy(id
->nsproxy
);
1307 req
->flags
|= REQ_F_INFLIGHT
;
1309 spin_lock_irq(&ctx
->inflight_lock
);
1310 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
1311 spin_unlock_irq(&ctx
->inflight_lock
);
1312 req
->work
.flags
|= IO_WQ_WORK_FILES
;
1314 #ifdef CONFIG_BLK_CGROUP
1315 if (!(req
->work
.flags
& IO_WQ_WORK_BLKCG
) &&
1316 (def
->work_flags
& IO_WQ_WORK_BLKCG
)) {
1318 if (id
->blkcg_css
!= blkcg_css()) {
1323 * This should be rare, either the cgroup is dying or the task
1324 * is moving cgroups. Just punt to root for the handful of ios.
1326 if (css_tryget_online(id
->blkcg_css
))
1327 req
->work
.flags
|= IO_WQ_WORK_BLKCG
;
1331 if (!(req
->work
.flags
& IO_WQ_WORK_CREDS
)) {
1332 if (id
->creds
!= current_cred())
1334 get_cred(id
->creds
);
1335 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
1338 if (!uid_eq(current
->loginuid
, id
->loginuid
) ||
1339 current
->sessionid
!= id
->sessionid
)
1342 if (!(req
->work
.flags
& IO_WQ_WORK_FS
) &&
1343 (def
->work_flags
& IO_WQ_WORK_FS
)) {
1344 if (current
->fs
!= id
->fs
)
1346 spin_lock(&id
->fs
->lock
);
1347 if (!id
->fs
->in_exec
) {
1349 req
->work
.flags
|= IO_WQ_WORK_FS
;
1351 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1353 spin_unlock(¤t
->fs
->lock
);
1359 static void io_prep_async_work(struct io_kiocb
*req
)
1361 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1362 struct io_ring_ctx
*ctx
= req
->ctx
;
1363 struct io_identity
*id
;
1365 io_req_init_async(req
);
1366 id
= req
->work
.identity
;
1368 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1369 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1371 if (req
->flags
& REQ_F_ISREG
) {
1372 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1373 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1375 if (def
->unbound_nonreg_file
)
1376 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1379 /* ->mm can never change on us */
1380 if (!(req
->work
.flags
& IO_WQ_WORK_MM
) &&
1381 (def
->work_flags
& IO_WQ_WORK_MM
)) {
1383 req
->work
.flags
|= IO_WQ_WORK_MM
;
1386 /* if we fail grabbing identity, we must COW, regrab, and retry */
1387 if (io_grab_identity(req
))
1390 if (!io_identity_cow(req
))
1393 /* can't fail at this point */
1394 if (!io_grab_identity(req
))
1398 static void io_prep_async_link(struct io_kiocb
*req
)
1400 struct io_kiocb
*cur
;
1402 io_prep_async_work(req
);
1403 if (req
->flags
& REQ_F_LINK_HEAD
)
1404 list_for_each_entry(cur
, &req
->link_list
, link_list
)
1405 io_prep_async_work(cur
);
1408 static struct io_kiocb
*__io_queue_async_work(struct io_kiocb
*req
)
1410 struct io_ring_ctx
*ctx
= req
->ctx
;
1411 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1413 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1414 &req
->work
, req
->flags
);
1415 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1419 static void io_queue_async_work(struct io_kiocb
*req
)
1421 struct io_kiocb
*link
;
1423 /* init ->work of the whole link before punting */
1424 io_prep_async_link(req
);
1425 link
= __io_queue_async_work(req
);
1428 io_queue_linked_timeout(link
);
1431 static void io_kill_timeout(struct io_kiocb
*req
)
1433 struct io_timeout_data
*io
= req
->async_data
;
1436 ret
= hrtimer_try_to_cancel(&io
->timer
);
1438 atomic_set(&req
->ctx
->cq_timeouts
,
1439 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1440 list_del_init(&req
->timeout
.list
);
1441 io_cqring_fill_event(req
, 0);
1442 io_put_req_deferred(req
, 1);
1446 static bool io_task_match(struct io_kiocb
*req
, struct task_struct
*tsk
)
1448 struct io_ring_ctx
*ctx
= req
->ctx
;
1450 if (!tsk
|| req
->task
== tsk
)
1452 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1453 if (ctx
->sq_data
&& req
->task
== ctx
->sq_data
->thread
)
1460 * Returns true if we found and killed one or more timeouts
1462 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
)
1464 struct io_kiocb
*req
, *tmp
;
1467 spin_lock_irq(&ctx
->completion_lock
);
1468 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
1469 if (io_task_match(req
, tsk
)) {
1470 io_kill_timeout(req
);
1474 spin_unlock_irq(&ctx
->completion_lock
);
1475 return canceled
!= 0;
1478 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1481 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1482 struct io_defer_entry
, list
);
1483 struct io_kiocb
*link
;
1485 if (req_need_defer(de
->req
, de
->seq
))
1487 list_del_init(&de
->list
);
1488 /* punt-init is done before queueing for defer */
1489 link
= __io_queue_async_work(de
->req
);
1491 __io_queue_linked_timeout(link
);
1492 /* drop submission reference */
1493 io_put_req_deferred(link
, 1);
1496 } while (!list_empty(&ctx
->defer_list
));
1499 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1501 while (!list_empty(&ctx
->timeout_list
)) {
1502 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1503 struct io_kiocb
, timeout
.list
);
1505 if (io_is_timeout_noseq(req
))
1507 if (req
->timeout
.target_seq
!= ctx
->cached_cq_tail
1508 - atomic_read(&ctx
->cq_timeouts
))
1511 list_del_init(&req
->timeout
.list
);
1512 io_kill_timeout(req
);
1516 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1518 io_flush_timeouts(ctx
);
1519 __io_commit_cqring(ctx
);
1521 if (unlikely(!list_empty(&ctx
->defer_list
)))
1522 __io_queue_deferred(ctx
);
1525 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1527 struct io_rings
*r
= ctx
->rings
;
1529 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1532 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1534 struct io_rings
*rings
= ctx
->rings
;
1537 tail
= ctx
->cached_cq_tail
;
1539 * writes to the cq entry need to come after reading head; the
1540 * control dependency is enough as we're using WRITE_ONCE to
1543 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1546 ctx
->cached_cq_tail
++;
1547 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1550 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1554 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1556 if (!ctx
->eventfd_async
)
1558 return io_wq_current_is_worker();
1561 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1563 if (waitqueue_active(&ctx
->wait
))
1564 wake_up(&ctx
->wait
);
1565 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1566 wake_up(&ctx
->sq_data
->wait
);
1567 if (io_should_trigger_evfd(ctx
))
1568 eventfd_signal(ctx
->cq_ev_fd
, 1);
1571 static void io_cqring_mark_overflow(struct io_ring_ctx
*ctx
)
1573 if (list_empty(&ctx
->cq_overflow_list
)) {
1574 clear_bit(0, &ctx
->sq_check_overflow
);
1575 clear_bit(0, &ctx
->cq_check_overflow
);
1576 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1580 static inline bool io_match_files(struct io_kiocb
*req
,
1581 struct files_struct
*files
)
1585 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
1586 (req
->work
.flags
& IO_WQ_WORK_FILES
))
1587 return req
->work
.identity
->files
== files
;
1591 /* Returns true if there are no backlogged entries after the flush */
1592 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1593 struct task_struct
*tsk
,
1594 struct files_struct
*files
)
1596 struct io_rings
*rings
= ctx
->rings
;
1597 struct io_kiocb
*req
, *tmp
;
1598 struct io_uring_cqe
*cqe
;
1599 unsigned long flags
;
1603 if (list_empty_careful(&ctx
->cq_overflow_list
))
1605 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1606 rings
->cq_ring_entries
))
1610 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1612 /* if force is set, the ring is going away. always drop after that */
1614 ctx
->cq_overflow_flushed
= 1;
1617 list_for_each_entry_safe(req
, tmp
, &ctx
->cq_overflow_list
, compl.list
) {
1618 if (tsk
&& req
->task
!= tsk
)
1620 if (!io_match_files(req
, files
))
1623 cqe
= io_get_cqring(ctx
);
1627 list_move(&req
->compl.list
, &list
);
1629 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1630 WRITE_ONCE(cqe
->res
, req
->result
);
1631 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1633 ctx
->cached_cq_overflow
++;
1634 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1635 ctx
->cached_cq_overflow
);
1639 io_commit_cqring(ctx
);
1640 io_cqring_mark_overflow(ctx
);
1642 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1643 io_cqring_ev_posted(ctx
);
1645 while (!list_empty(&list
)) {
1646 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1647 list_del(&req
->compl.list
);
1654 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1656 struct io_ring_ctx
*ctx
= req
->ctx
;
1657 struct io_uring_cqe
*cqe
;
1659 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1662 * If we can't get a cq entry, userspace overflowed the
1663 * submission (by quite a lot). Increment the overflow count in
1666 cqe
= io_get_cqring(ctx
);
1668 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1669 WRITE_ONCE(cqe
->res
, res
);
1670 WRITE_ONCE(cqe
->flags
, cflags
);
1671 } else if (ctx
->cq_overflow_flushed
|| req
->task
->io_uring
->in_idle
) {
1673 * If we're in ring overflow flush mode, or in task cancel mode,
1674 * then we cannot store the request for later flushing, we need
1675 * to drop it on the floor.
1677 ctx
->cached_cq_overflow
++;
1678 WRITE_ONCE(ctx
->rings
->cq_overflow
, ctx
->cached_cq_overflow
);
1680 if (list_empty(&ctx
->cq_overflow_list
)) {
1681 set_bit(0, &ctx
->sq_check_overflow
);
1682 set_bit(0, &ctx
->cq_check_overflow
);
1683 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1687 req
->compl.cflags
= cflags
;
1688 refcount_inc(&req
->refs
);
1689 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1693 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1695 __io_cqring_fill_event(req
, res
, 0);
1698 static void io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1700 struct io_ring_ctx
*ctx
= req
->ctx
;
1701 unsigned long flags
;
1703 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1704 __io_cqring_fill_event(req
, res
, cflags
);
1705 io_commit_cqring(ctx
);
1706 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1708 io_cqring_ev_posted(ctx
);
1711 static void io_submit_flush_completions(struct io_comp_state
*cs
)
1713 struct io_ring_ctx
*ctx
= cs
->ctx
;
1715 spin_lock_irq(&ctx
->completion_lock
);
1716 while (!list_empty(&cs
->list
)) {
1717 struct io_kiocb
*req
;
1719 req
= list_first_entry(&cs
->list
, struct io_kiocb
, compl.list
);
1720 list_del(&req
->compl.list
);
1721 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
1724 * io_free_req() doesn't care about completion_lock unless one
1725 * of these flags is set. REQ_F_WORK_INITIALIZED is in the list
1726 * because of a potential deadlock with req->work.fs->lock
1728 if (req
->flags
& (REQ_F_FAIL_LINK
|REQ_F_LINK_TIMEOUT
1729 |REQ_F_WORK_INITIALIZED
)) {
1730 spin_unlock_irq(&ctx
->completion_lock
);
1732 spin_lock_irq(&ctx
->completion_lock
);
1737 io_commit_cqring(ctx
);
1738 spin_unlock_irq(&ctx
->completion_lock
);
1740 io_cqring_ev_posted(ctx
);
1744 static void __io_req_complete(struct io_kiocb
*req
, long res
, unsigned cflags
,
1745 struct io_comp_state
*cs
)
1748 io_cqring_add_event(req
, res
, cflags
);
1753 req
->compl.cflags
= cflags
;
1754 list_add_tail(&req
->compl.list
, &cs
->list
);
1756 io_submit_flush_completions(cs
);
1760 static void io_req_complete(struct io_kiocb
*req
, long res
)
1762 __io_req_complete(req
, res
, 0, NULL
);
1765 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1767 return req
== (struct io_kiocb
*)
1768 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1771 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1773 struct io_kiocb
*req
;
1775 req
= ctx
->fallback_req
;
1776 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1782 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1783 struct io_submit_state
*state
)
1785 if (!state
->free_reqs
) {
1786 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1790 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1791 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1794 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1795 * retry single alloc to be on the safe side.
1797 if (unlikely(ret
<= 0)) {
1798 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1799 if (!state
->reqs
[0])
1803 state
->free_reqs
= ret
;
1807 return state
->reqs
[state
->free_reqs
];
1809 return io_get_fallback_req(ctx
);
1812 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1816 percpu_ref_put(req
->fixed_file_refs
);
1821 static void io_dismantle_req(struct io_kiocb
*req
)
1825 if (req
->async_data
)
1826 kfree(req
->async_data
);
1828 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1830 io_req_clean_work(req
);
1833 static void __io_free_req(struct io_kiocb
*req
)
1835 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1836 struct io_ring_ctx
*ctx
= req
->ctx
;
1838 io_dismantle_req(req
);
1840 percpu_counter_dec(&tctx
->inflight
);
1842 wake_up(&tctx
->wait
);
1843 put_task_struct(req
->task
);
1845 if (likely(!io_is_fallback_req(req
)))
1846 kmem_cache_free(req_cachep
, req
);
1848 clear_bit_unlock(0, (unsigned long *) &ctx
->fallback_req
);
1849 percpu_ref_put(&ctx
->refs
);
1852 static void io_kill_linked_timeout(struct io_kiocb
*req
)
1854 struct io_ring_ctx
*ctx
= req
->ctx
;
1855 struct io_kiocb
*link
;
1856 bool cancelled
= false;
1857 unsigned long flags
;
1859 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1860 link
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
1863 * Can happen if a linked timeout fired and link had been like
1864 * req -> link t-out -> link t-out [-> ...]
1866 if (link
&& (link
->flags
& REQ_F_LTIMEOUT_ACTIVE
)) {
1867 struct io_timeout_data
*io
= link
->async_data
;
1870 list_del_init(&link
->link_list
);
1871 ret
= hrtimer_try_to_cancel(&io
->timer
);
1873 io_cqring_fill_event(link
, -ECANCELED
);
1874 io_commit_cqring(ctx
);
1878 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1879 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1882 io_cqring_ev_posted(ctx
);
1887 static struct io_kiocb
*io_req_link_next(struct io_kiocb
*req
)
1889 struct io_kiocb
*nxt
;
1892 * The list should never be empty when we are called here. But could
1893 * potentially happen if the chain is messed up, check to be on the
1896 if (unlikely(list_empty(&req
->link_list
)))
1899 nxt
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1900 list_del_init(&req
->link_list
);
1901 if (!list_empty(&nxt
->link_list
))
1902 nxt
->flags
|= REQ_F_LINK_HEAD
;
1907 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
1909 static void io_fail_links(struct io_kiocb
*req
)
1911 struct io_ring_ctx
*ctx
= req
->ctx
;
1912 unsigned long flags
;
1914 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1915 while (!list_empty(&req
->link_list
)) {
1916 struct io_kiocb
*link
= list_first_entry(&req
->link_list
,
1917 struct io_kiocb
, link_list
);
1919 list_del_init(&link
->link_list
);
1920 trace_io_uring_fail_link(req
, link
);
1922 io_cqring_fill_event(link
, -ECANCELED
);
1925 * It's ok to free under spinlock as they're not linked anymore,
1926 * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
1929 if (link
->flags
& REQ_F_WORK_INITIALIZED
)
1930 io_put_req_deferred(link
, 2);
1932 io_double_put_req(link
);
1935 io_commit_cqring(ctx
);
1936 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1938 io_cqring_ev_posted(ctx
);
1941 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
1943 req
->flags
&= ~REQ_F_LINK_HEAD
;
1944 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
1945 io_kill_linked_timeout(req
);
1948 * If LINK is set, we have dependent requests in this chain. If we
1949 * didn't fail this request, queue the first one up, moving any other
1950 * dependencies to the next request. In case of failure, fail the rest
1953 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
)))
1954 return io_req_link_next(req
);
1959 static struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
1961 if (likely(!(req
->flags
& REQ_F_LINK_HEAD
)))
1963 return __io_req_find_next(req
);
1966 static int io_req_task_work_add(struct io_kiocb
*req
, bool twa_signal_ok
)
1968 struct task_struct
*tsk
= req
->task
;
1969 struct io_ring_ctx
*ctx
= req
->ctx
;
1970 enum task_work_notify_mode notify
;
1973 if (tsk
->flags
& PF_EXITING
)
1977 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
1978 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
1979 * processing task_work. There's no reliable way to tell if TWA_RESUME
1983 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
) && twa_signal_ok
)
1984 notify
= TWA_SIGNAL
;
1986 ret
= task_work_add(tsk
, &req
->task_work
, notify
);
1988 wake_up_process(tsk
);
1993 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
1995 struct io_ring_ctx
*ctx
= req
->ctx
;
1997 spin_lock_irq(&ctx
->completion_lock
);
1998 io_cqring_fill_event(req
, error
);
1999 io_commit_cqring(ctx
);
2000 spin_unlock_irq(&ctx
->completion_lock
);
2002 io_cqring_ev_posted(ctx
);
2003 req_set_fail_links(req
);
2004 io_double_put_req(req
);
2007 static void io_req_task_cancel(struct callback_head
*cb
)
2009 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2010 struct io_ring_ctx
*ctx
= req
->ctx
;
2012 __io_req_task_cancel(req
, -ECANCELED
);
2013 percpu_ref_put(&ctx
->refs
);
2016 static void __io_req_task_submit(struct io_kiocb
*req
)
2018 struct io_ring_ctx
*ctx
= req
->ctx
;
2020 if (!__io_sq_thread_acquire_mm(ctx
)) {
2021 mutex_lock(&ctx
->uring_lock
);
2022 __io_queue_sqe(req
, NULL
);
2023 mutex_unlock(&ctx
->uring_lock
);
2025 __io_req_task_cancel(req
, -EFAULT
);
2029 static void io_req_task_submit(struct callback_head
*cb
)
2031 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2032 struct io_ring_ctx
*ctx
= req
->ctx
;
2034 __io_req_task_submit(req
);
2035 percpu_ref_put(&ctx
->refs
);
2038 static void io_req_task_queue(struct io_kiocb
*req
)
2042 init_task_work(&req
->task_work
, io_req_task_submit
);
2043 percpu_ref_get(&req
->ctx
->refs
);
2045 ret
= io_req_task_work_add(req
, true);
2046 if (unlikely(ret
)) {
2047 struct task_struct
*tsk
;
2049 init_task_work(&req
->task_work
, io_req_task_cancel
);
2050 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2051 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2052 wake_up_process(tsk
);
2056 static void io_queue_next(struct io_kiocb
*req
)
2058 struct io_kiocb
*nxt
= io_req_find_next(req
);
2061 io_req_task_queue(nxt
);
2064 static void io_free_req(struct io_kiocb
*req
)
2071 void *reqs
[IO_IOPOLL_BATCH
];
2074 struct task_struct
*task
;
2078 static inline void io_init_req_batch(struct req_batch
*rb
)
2085 static void __io_req_free_batch_flush(struct io_ring_ctx
*ctx
,
2086 struct req_batch
*rb
)
2088 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
2089 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
2093 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2094 struct req_batch
*rb
)
2097 __io_req_free_batch_flush(ctx
, rb
);
2099 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2101 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2102 put_task_struct_many(rb
->task
, rb
->task_refs
);
2107 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
)
2109 if (unlikely(io_is_fallback_req(req
))) {
2113 if (req
->flags
& REQ_F_LINK_HEAD
)
2116 if (req
->task
!= rb
->task
) {
2118 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2120 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2121 put_task_struct_many(rb
->task
, rb
->task_refs
);
2123 rb
->task
= req
->task
;
2128 io_dismantle_req(req
);
2129 rb
->reqs
[rb
->to_free
++] = req
;
2130 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
2131 __io_req_free_batch_flush(req
->ctx
, rb
);
2135 * Drop reference to request, return next in chain (if there is one) if this
2136 * was the last reference to this request.
2138 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2140 struct io_kiocb
*nxt
= NULL
;
2142 if (refcount_dec_and_test(&req
->refs
)) {
2143 nxt
= io_req_find_next(req
);
2149 static void io_put_req(struct io_kiocb
*req
)
2151 if (refcount_dec_and_test(&req
->refs
))
2155 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2157 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2162 static void io_free_req_deferred(struct io_kiocb
*req
)
2166 init_task_work(&req
->task_work
, io_put_req_deferred_cb
);
2167 ret
= io_req_task_work_add(req
, true);
2168 if (unlikely(ret
)) {
2169 struct task_struct
*tsk
;
2171 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2172 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2173 wake_up_process(tsk
);
2177 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2179 if (refcount_sub_and_test(refs
, &req
->refs
))
2180 io_free_req_deferred(req
);
2183 static struct io_wq_work
*io_steal_work(struct io_kiocb
*req
)
2185 struct io_kiocb
*nxt
;
2188 * A ref is owned by io-wq in which context we're. So, if that's the
2189 * last one, it's safe to steal next work. False negatives are Ok,
2190 * it just will be re-punted async in io_put_work()
2192 if (refcount_read(&req
->refs
) != 1)
2195 nxt
= io_req_find_next(req
);
2196 return nxt
? &nxt
->work
: NULL
;
2199 static void io_double_put_req(struct io_kiocb
*req
)
2201 /* drop both submit and complete references */
2202 if (refcount_sub_and_test(2, &req
->refs
))
2206 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
2208 struct io_rings
*rings
= ctx
->rings
;
2210 if (test_bit(0, &ctx
->cq_check_overflow
)) {
2212 * noflush == true is from the waitqueue handler, just ensure
2213 * we wake up the task, and the next invocation will flush the
2214 * entries. We cannot safely to it from here.
2216 if (noflush
&& !list_empty(&ctx
->cq_overflow_list
))
2219 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
2222 /* See comment at the top of this file */
2224 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
2227 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2229 struct io_rings
*rings
= ctx
->rings
;
2231 /* make sure SQ entry isn't read before tail */
2232 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2235 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2237 unsigned int cflags
;
2239 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2240 cflags
|= IORING_CQE_F_BUFFER
;
2241 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2246 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2248 struct io_buffer
*kbuf
;
2250 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2251 return io_put_kbuf(req
, kbuf
);
2254 static inline bool io_run_task_work(void)
2257 * Not safe to run on exiting task, and the task_work handling will
2258 * not add work to such a task.
2260 if (unlikely(current
->flags
& PF_EXITING
))
2262 if (current
->task_works
) {
2263 __set_current_state(TASK_RUNNING
);
2271 static void io_iopoll_queue(struct list_head
*again
)
2273 struct io_kiocb
*req
;
2276 req
= list_first_entry(again
, struct io_kiocb
, inflight_entry
);
2277 list_del(&req
->inflight_entry
);
2278 __io_complete_rw(req
, -EAGAIN
, 0, NULL
);
2279 } while (!list_empty(again
));
2283 * Find and free completed poll iocbs
2285 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2286 struct list_head
*done
)
2288 struct req_batch rb
;
2289 struct io_kiocb
*req
;
2292 /* order with ->result store in io_complete_rw_iopoll() */
2295 io_init_req_batch(&rb
);
2296 while (!list_empty(done
)) {
2299 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2300 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2302 req
->iopoll_completed
= 0;
2303 list_move_tail(&req
->inflight_entry
, &again
);
2306 list_del(&req
->inflight_entry
);
2308 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2309 cflags
= io_put_rw_kbuf(req
);
2311 __io_cqring_fill_event(req
, req
->result
, cflags
);
2314 if (refcount_dec_and_test(&req
->refs
))
2315 io_req_free_batch(&rb
, req
);
2318 io_commit_cqring(ctx
);
2319 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
2320 io_cqring_ev_posted(ctx
);
2321 io_req_free_batch_finish(ctx
, &rb
);
2323 if (!list_empty(&again
))
2324 io_iopoll_queue(&again
);
2327 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2330 struct io_kiocb
*req
, *tmp
;
2336 * Only spin for completions if we don't have multiple devices hanging
2337 * off our complete list, and we're under the requested amount.
2339 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2342 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2343 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2346 * Move completed and retryable entries to our local lists.
2347 * If we find a request that requires polling, break out
2348 * and complete those lists first, if we have entries there.
2350 if (READ_ONCE(req
->iopoll_completed
)) {
2351 list_move_tail(&req
->inflight_entry
, &done
);
2354 if (!list_empty(&done
))
2357 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2361 /* iopoll may have completed current req */
2362 if (READ_ONCE(req
->iopoll_completed
))
2363 list_move_tail(&req
->inflight_entry
, &done
);
2370 if (!list_empty(&done
))
2371 io_iopoll_complete(ctx
, nr_events
, &done
);
2377 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2378 * non-spinning poll check - we'll still enter the driver poll loop, but only
2379 * as a non-spinning completion check.
2381 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2384 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2387 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2390 if (*nr_events
>= min
)
2398 * We can't just wait for polled events to come to us, we have to actively
2399 * find and complete them.
2401 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2403 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2406 mutex_lock(&ctx
->uring_lock
);
2407 while (!list_empty(&ctx
->iopoll_list
)) {
2408 unsigned int nr_events
= 0;
2410 io_do_iopoll(ctx
, &nr_events
, 0);
2412 /* let it sleep and repeat later if can't complete a request */
2416 * Ensure we allow local-to-the-cpu processing to take place,
2417 * in this case we need to ensure that we reap all events.
2418 * Also let task_work, etc. to progress by releasing the mutex
2420 if (need_resched()) {
2421 mutex_unlock(&ctx
->uring_lock
);
2423 mutex_lock(&ctx
->uring_lock
);
2426 mutex_unlock(&ctx
->uring_lock
);
2429 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2431 unsigned int nr_events
= 0;
2432 int iters
= 0, ret
= 0;
2435 * We disallow the app entering submit/complete with polling, but we
2436 * still need to lock the ring to prevent racing with polled issue
2437 * that got punted to a workqueue.
2439 mutex_lock(&ctx
->uring_lock
);
2442 * Don't enter poll loop if we already have events pending.
2443 * If we do, we can potentially be spinning for commands that
2444 * already triggered a CQE (eg in error).
2446 if (io_cqring_events(ctx
, false))
2450 * If a submit got punted to a workqueue, we can have the
2451 * application entering polling for a command before it gets
2452 * issued. That app will hold the uring_lock for the duration
2453 * of the poll right here, so we need to take a breather every
2454 * now and then to ensure that the issue has a chance to add
2455 * the poll to the issued list. Otherwise we can spin here
2456 * forever, while the workqueue is stuck trying to acquire the
2459 if (!(++iters
& 7)) {
2460 mutex_unlock(&ctx
->uring_lock
);
2462 mutex_lock(&ctx
->uring_lock
);
2465 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2469 } while (min
&& !nr_events
&& !need_resched());
2471 mutex_unlock(&ctx
->uring_lock
);
2475 static void kiocb_end_write(struct io_kiocb
*req
)
2478 * Tell lockdep we inherited freeze protection from submission
2481 if (req
->flags
& REQ_F_ISREG
) {
2482 struct inode
*inode
= file_inode(req
->file
);
2484 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2486 file_end_write(req
->file
);
2489 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
,
2490 struct io_comp_state
*cs
)
2492 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2495 if (kiocb
->ki_flags
& IOCB_WRITE
)
2496 kiocb_end_write(req
);
2498 if (res
!= req
->result
)
2499 req_set_fail_links(req
);
2500 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2501 cflags
= io_put_rw_kbuf(req
);
2502 __io_req_complete(req
, res
, cflags
, cs
);
2506 static bool io_resubmit_prep(struct io_kiocb
*req
, int error
)
2508 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2509 ssize_t ret
= -ECANCELED
;
2510 struct iov_iter iter
;
2518 switch (req
->opcode
) {
2519 case IORING_OP_READV
:
2520 case IORING_OP_READ_FIXED
:
2521 case IORING_OP_READ
:
2524 case IORING_OP_WRITEV
:
2525 case IORING_OP_WRITE_FIXED
:
2526 case IORING_OP_WRITE
:
2530 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2535 if (!req
->async_data
) {
2536 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2539 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, &iter
, false);
2547 req_set_fail_links(req
);
2548 io_req_complete(req
, ret
);
2553 static bool io_rw_reissue(struct io_kiocb
*req
, long res
)
2556 umode_t mode
= file_inode(req
->file
)->i_mode
;
2559 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2561 if ((res
!= -EAGAIN
&& res
!= -EOPNOTSUPP
) || io_wq_current_is_worker())
2564 ret
= io_sq_thread_acquire_mm(req
->ctx
, req
);
2566 if (io_resubmit_prep(req
, ret
)) {
2567 refcount_inc(&req
->refs
);
2568 io_queue_async_work(req
);
2576 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2577 struct io_comp_state
*cs
)
2579 if (!io_rw_reissue(req
, res
))
2580 io_complete_rw_common(&req
->rw
.kiocb
, res
, cs
);
2583 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2585 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2587 __io_complete_rw(req
, res
, res2
, NULL
);
2590 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2592 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2594 if (kiocb
->ki_flags
& IOCB_WRITE
)
2595 kiocb_end_write(req
);
2597 if (res
!= -EAGAIN
&& res
!= req
->result
)
2598 req_set_fail_links(req
);
2600 WRITE_ONCE(req
->result
, res
);
2601 /* order with io_poll_complete() checking ->result */
2603 WRITE_ONCE(req
->iopoll_completed
, 1);
2607 * After the iocb has been issued, it's safe to be found on the poll list.
2608 * Adding the kiocb to the list AFTER submission ensures that we don't
2609 * find it from a io_iopoll_getevents() thread before the issuer is done
2610 * accessing the kiocb cookie.
2612 static void io_iopoll_req_issued(struct io_kiocb
*req
)
2614 struct io_ring_ctx
*ctx
= req
->ctx
;
2617 * Track whether we have multiple files in our lists. This will impact
2618 * how we do polling eventually, not spinning if we're on potentially
2619 * different devices.
2621 if (list_empty(&ctx
->iopoll_list
)) {
2622 ctx
->poll_multi_file
= false;
2623 } else if (!ctx
->poll_multi_file
) {
2624 struct io_kiocb
*list_req
;
2626 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2628 if (list_req
->file
!= req
->file
)
2629 ctx
->poll_multi_file
= true;
2633 * For fast devices, IO may have already completed. If it has, add
2634 * it to the front so we find it first.
2636 if (READ_ONCE(req
->iopoll_completed
))
2637 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2639 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2641 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2642 wq_has_sleeper(&ctx
->sq_data
->wait
))
2643 wake_up(&ctx
->sq_data
->wait
);
2646 static void __io_state_file_put(struct io_submit_state
*state
)
2648 if (state
->has_refs
)
2649 fput_many(state
->file
, state
->has_refs
);
2653 static inline void io_state_file_put(struct io_submit_state
*state
)
2656 __io_state_file_put(state
);
2660 * Get as many references to a file as we have IOs left in this submission,
2661 * assuming most submissions are for one file, or at least that each file
2662 * has more than one submission.
2664 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2670 if (state
->fd
== fd
) {
2674 __io_state_file_put(state
);
2676 state
->file
= fget_many(fd
, state
->ios_left
);
2681 state
->has_refs
= state
->ios_left
- 1;
2685 static bool io_bdev_nowait(struct block_device
*bdev
)
2688 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2695 * If we tracked the file through the SCM inflight mechanism, we could support
2696 * any file. For now, just ensure that anything potentially problematic is done
2699 static bool io_file_supports_async(struct file
*file
, int rw
)
2701 umode_t mode
= file_inode(file
)->i_mode
;
2703 if (S_ISBLK(mode
)) {
2704 if (io_bdev_nowait(file
->f_inode
->i_bdev
))
2708 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2710 if (S_ISREG(mode
)) {
2711 if (io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2712 file
->f_op
!= &io_uring_fops
)
2717 /* any ->read/write should understand O_NONBLOCK */
2718 if (file
->f_flags
& O_NONBLOCK
)
2721 if (!(file
->f_mode
& FMODE_NOWAIT
))
2725 return file
->f_op
->read_iter
!= NULL
;
2727 return file
->f_op
->write_iter
!= NULL
;
2730 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2732 struct io_ring_ctx
*ctx
= req
->ctx
;
2733 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2737 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2738 req
->flags
|= REQ_F_ISREG
;
2740 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2741 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2742 req
->flags
|= REQ_F_CUR_POS
;
2743 kiocb
->ki_pos
= req
->file
->f_pos
;
2745 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2746 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2747 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2751 ioprio
= READ_ONCE(sqe
->ioprio
);
2753 ret
= ioprio_check_cap(ioprio
);
2757 kiocb
->ki_ioprio
= ioprio
;
2759 kiocb
->ki_ioprio
= get_current_ioprio();
2761 /* don't allow async punt if RWF_NOWAIT was requested */
2762 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2763 req
->flags
|= REQ_F_NOWAIT
;
2765 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2766 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2767 !kiocb
->ki_filp
->f_op
->iopoll
)
2770 kiocb
->ki_flags
|= IOCB_HIPRI
;
2771 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2772 req
->iopoll_completed
= 0;
2774 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2776 kiocb
->ki_complete
= io_complete_rw
;
2779 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2780 req
->rw
.len
= READ_ONCE(sqe
->len
);
2781 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2785 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2791 case -ERESTARTNOINTR
:
2792 case -ERESTARTNOHAND
:
2793 case -ERESTART_RESTARTBLOCK
:
2795 * We can't just restart the syscall, since previously
2796 * submitted sqes may already be in progress. Just fail this
2802 kiocb
->ki_complete(kiocb
, ret
, 0);
2806 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2807 struct io_comp_state
*cs
)
2809 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2810 struct io_async_rw
*io
= req
->async_data
;
2812 /* add previously done IO, if any */
2813 if (io
&& io
->bytes_done
> 0) {
2815 ret
= io
->bytes_done
;
2817 ret
+= io
->bytes_done
;
2820 if (req
->flags
& REQ_F_CUR_POS
)
2821 req
->file
->f_pos
= kiocb
->ki_pos
;
2822 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2823 __io_complete_rw(req
, ret
, 0, cs
);
2825 io_rw_done(kiocb
, ret
);
2828 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2829 struct iov_iter
*iter
)
2831 struct io_ring_ctx
*ctx
= req
->ctx
;
2832 size_t len
= req
->rw
.len
;
2833 struct io_mapped_ubuf
*imu
;
2834 u16 index
, buf_index
= req
->buf_index
;
2838 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2840 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2841 imu
= &ctx
->user_bufs
[index
];
2842 buf_addr
= req
->rw
.addr
;
2845 if (buf_addr
+ len
< buf_addr
)
2847 /* not inside the mapped region */
2848 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2852 * May not be a start of buffer, set size appropriately
2853 * and advance us to the beginning.
2855 offset
= buf_addr
- imu
->ubuf
;
2856 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2860 * Don't use iov_iter_advance() here, as it's really slow for
2861 * using the latter parts of a big fixed buffer - it iterates
2862 * over each segment manually. We can cheat a bit here, because
2865 * 1) it's a BVEC iter, we set it up
2866 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2867 * first and last bvec
2869 * So just find our index, and adjust the iterator afterwards.
2870 * If the offset is within the first bvec (or the whole first
2871 * bvec, just use iov_iter_advance(). This makes it easier
2872 * since we can just skip the first segment, which may not
2873 * be PAGE_SIZE aligned.
2875 const struct bio_vec
*bvec
= imu
->bvec
;
2877 if (offset
<= bvec
->bv_len
) {
2878 iov_iter_advance(iter
, offset
);
2880 unsigned long seg_skip
;
2882 /* skip first vec */
2883 offset
-= bvec
->bv_len
;
2884 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2886 iter
->bvec
= bvec
+ seg_skip
;
2887 iter
->nr_segs
-= seg_skip
;
2888 iter
->count
-= bvec
->bv_len
+ offset
;
2889 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2896 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2899 mutex_unlock(&ctx
->uring_lock
);
2902 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2905 * "Normal" inline submissions always hold the uring_lock, since we
2906 * grab it from the system call. Same is true for the SQPOLL offload.
2907 * The only exception is when we've detached the request and issue it
2908 * from an async worker thread, grab the lock for that case.
2911 mutex_lock(&ctx
->uring_lock
);
2914 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2915 int bgid
, struct io_buffer
*kbuf
,
2918 struct io_buffer
*head
;
2920 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2923 io_ring_submit_lock(req
->ctx
, needs_lock
);
2925 lockdep_assert_held(&req
->ctx
->uring_lock
);
2927 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
2929 if (!list_empty(&head
->list
)) {
2930 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2932 list_del(&kbuf
->list
);
2935 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
2937 if (*len
> kbuf
->len
)
2940 kbuf
= ERR_PTR(-ENOBUFS
);
2943 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2948 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2951 struct io_buffer
*kbuf
;
2954 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2955 bgid
= req
->buf_index
;
2956 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2959 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2960 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2961 return u64_to_user_ptr(kbuf
->addr
);
2964 #ifdef CONFIG_COMPAT
2965 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2968 struct compat_iovec __user
*uiov
;
2969 compat_ssize_t clen
;
2973 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2974 if (!access_ok(uiov
, sizeof(*uiov
)))
2976 if (__get_user(clen
, &uiov
->iov_len
))
2982 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2984 return PTR_ERR(buf
);
2985 iov
[0].iov_base
= buf
;
2986 iov
[0].iov_len
= (compat_size_t
) len
;
2991 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2994 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2998 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3001 len
= iov
[0].iov_len
;
3004 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3006 return PTR_ERR(buf
);
3007 iov
[0].iov_base
= buf
;
3008 iov
[0].iov_len
= len
;
3012 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3015 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3016 struct io_buffer
*kbuf
;
3018 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3019 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3020 iov
[0].iov_len
= kbuf
->len
;
3025 else if (req
->rw
.len
> 1)
3028 #ifdef CONFIG_COMPAT
3029 if (req
->ctx
->compat
)
3030 return io_compat_import(req
, iov
, needs_lock
);
3033 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3036 static ssize_t
__io_import_iovec(int rw
, struct io_kiocb
*req
,
3037 struct iovec
**iovec
, struct iov_iter
*iter
,
3040 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3041 size_t sqe_len
= req
->rw
.len
;
3045 opcode
= req
->opcode
;
3046 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3048 return io_import_fixed(req
, rw
, iter
);
3051 /* buffer index only valid with fixed read/write, or buffer select */
3052 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3055 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3056 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3057 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3059 return PTR_ERR(buf
);
3060 req
->rw
.len
= sqe_len
;
3063 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3065 return ret
< 0 ? ret
: sqe_len
;
3068 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3069 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3071 ret
= (*iovec
)->iov_len
;
3072 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
3078 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3082 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
3083 struct iovec
**iovec
, struct iov_iter
*iter
,
3086 struct io_async_rw
*iorw
= req
->async_data
;
3089 return __io_import_iovec(rw
, req
, iovec
, iter
, needs_lock
);
3091 return iov_iter_count(&iorw
->iter
);
3094 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3096 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3100 * For files that don't have ->read_iter() and ->write_iter(), handle them
3101 * by looping over ->read() or ->write() manually.
3103 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3105 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3106 struct file
*file
= req
->file
;
3110 * Don't support polled IO through this interface, and we can't
3111 * support non-blocking either. For the latter, this just causes
3112 * the kiocb to be handled from an async context.
3114 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3116 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3119 while (iov_iter_count(iter
)) {
3123 if (!iov_iter_is_bvec(iter
)) {
3124 iovec
= iov_iter_iovec(iter
);
3126 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3127 iovec
.iov_len
= req
->rw
.len
;
3131 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3132 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3134 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3135 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3144 if (nr
!= iovec
.iov_len
)
3148 iov_iter_advance(iter
, nr
);
3154 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3155 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3157 struct io_async_rw
*rw
= req
->async_data
;
3159 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3160 rw
->free_iovec
= iovec
;
3162 /* can only be fixed buffers, no need to do anything */
3163 if (iter
->type
== ITER_BVEC
)
3166 unsigned iov_off
= 0;
3168 rw
->iter
.iov
= rw
->fast_iov
;
3169 if (iter
->iov
!= fast_iov
) {
3170 iov_off
= iter
->iov
- fast_iov
;
3171 rw
->iter
.iov
+= iov_off
;
3173 if (rw
->fast_iov
!= fast_iov
)
3174 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3175 sizeof(struct iovec
) * iter
->nr_segs
);
3177 req
->flags
|= REQ_F_NEED_CLEANUP
;
3181 static inline int __io_alloc_async_data(struct io_kiocb
*req
)
3183 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3184 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3185 return req
->async_data
== NULL
;
3188 static int io_alloc_async_data(struct io_kiocb
*req
)
3190 if (!io_op_defs
[req
->opcode
].needs_async_data
)
3193 return __io_alloc_async_data(req
);
3196 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3197 const struct iovec
*fast_iov
,
3198 struct iov_iter
*iter
, bool force
)
3200 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_data
)
3202 if (!req
->async_data
) {
3203 if (__io_alloc_async_data(req
))
3206 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3211 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3213 struct io_async_rw
*iorw
= req
->async_data
;
3214 struct iovec
*iov
= iorw
->fast_iov
;
3217 ret
= __io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3218 if (unlikely(ret
< 0))
3221 iorw
->bytes_done
= 0;
3222 iorw
->free_iovec
= iov
;
3224 req
->flags
|= REQ_F_NEED_CLEANUP
;
3228 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3232 ret
= io_prep_rw(req
, sqe
);
3236 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3239 /* either don't need iovec imported or already have it */
3240 if (!req
->async_data
)
3242 return io_rw_prep_async(req
, READ
);
3246 * This is our waitqueue callback handler, registered through lock_page_async()
3247 * when we initially tried to do the IO with the iocb armed our waitqueue.
3248 * This gets called when the page is unlocked, and we generally expect that to
3249 * happen when the page IO is completed and the page is now uptodate. This will
3250 * queue a task_work based retry of the operation, attempting to copy the data
3251 * again. If the latter fails because the page was NOT uptodate, then we will
3252 * do a thread based blocking retry of the operation. That's the unexpected
3255 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3256 int sync
, void *arg
)
3258 struct wait_page_queue
*wpq
;
3259 struct io_kiocb
*req
= wait
->private;
3260 struct wait_page_key
*key
= arg
;
3263 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3265 if (!wake_page_match(wpq
, key
))
3268 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3269 list_del_init(&wait
->entry
);
3271 init_task_work(&req
->task_work
, io_req_task_submit
);
3272 percpu_ref_get(&req
->ctx
->refs
);
3274 /* submit ref gets dropped, acquire a new one */
3275 refcount_inc(&req
->refs
);
3276 ret
= io_req_task_work_add(req
, true);
3277 if (unlikely(ret
)) {
3278 struct task_struct
*tsk
;
3280 /* queue just for cancelation */
3281 init_task_work(&req
->task_work
, io_req_task_cancel
);
3282 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
3283 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
3284 wake_up_process(tsk
);
3290 * This controls whether a given IO request should be armed for async page
3291 * based retry. If we return false here, the request is handed to the async
3292 * worker threads for retry. If we're doing buffered reads on a regular file,
3293 * we prepare a private wait_page_queue entry and retry the operation. This
3294 * will either succeed because the page is now uptodate and unlocked, or it
3295 * will register a callback when the page is unlocked at IO completion. Through
3296 * that callback, io_uring uses task_work to setup a retry of the operation.
3297 * That retry will attempt the buffered read again. The retry will generally
3298 * succeed, or in rare cases where it fails, we then fall back to using the
3299 * async worker threads for a blocking retry.
3301 static bool io_rw_should_retry(struct io_kiocb
*req
)
3303 struct io_async_rw
*rw
= req
->async_data
;
3304 struct wait_page_queue
*wait
= &rw
->wpq
;
3305 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3307 /* never retry for NOWAIT, we just complete with -EAGAIN */
3308 if (req
->flags
& REQ_F_NOWAIT
)
3311 /* Only for buffered IO */
3312 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3316 * just use poll if we can, and don't attempt if the fs doesn't
3317 * support callback based unlocks
3319 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3322 wait
->wait
.func
= io_async_buf_func
;
3323 wait
->wait
.private = req
;
3324 wait
->wait
.flags
= 0;
3325 INIT_LIST_HEAD(&wait
->wait
.entry
);
3326 kiocb
->ki_flags
|= IOCB_WAITQ
;
3327 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3328 kiocb
->ki_waitq
= wait
;
3332 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3334 if (req
->file
->f_op
->read_iter
)
3335 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3336 else if (req
->file
->f_op
->read
)
3337 return loop_rw_iter(READ
, req
, iter
);
3342 static int io_read(struct io_kiocb
*req
, bool force_nonblock
,
3343 struct io_comp_state
*cs
)
3345 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3346 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3347 struct iov_iter __iter
, *iter
= &__iter
;
3348 struct io_async_rw
*rw
= req
->async_data
;
3349 ssize_t io_size
, ret
, ret2
;
3356 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3359 iov_count
= iov_iter_count(iter
);
3361 req
->result
= io_size
;
3364 /* Ensure we clear previously set non-block flag */
3365 if (!force_nonblock
)
3366 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3368 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3371 /* If the file doesn't support async, just async punt */
3372 no_async
= force_nonblock
&& !io_file_supports_async(req
->file
, READ
);
3376 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), iov_count
);
3380 ret
= io_iter_do_read(req
, iter
);
3384 } else if (ret
== -EIOCBQUEUED
) {
3387 } else if (ret
== -EAGAIN
) {
3388 /* IOPOLL retry should happen for io-wq threads */
3389 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3391 /* no retry on NONBLOCK marked file */
3392 if (req
->file
->f_flags
& O_NONBLOCK
)
3394 /* some cases will consume bytes even on error returns */
3395 iov_iter_revert(iter
, iov_count
- iov_iter_count(iter
));
3398 } else if (ret
< 0) {
3399 /* make sure -ERESTARTSYS -> -EINTR is done */
3403 /* read it all, or we did blocking attempt. no retry. */
3404 if (!iov_iter_count(iter
) || !force_nonblock
||
3405 (req
->file
->f_flags
& O_NONBLOCK
))
3410 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3417 rw
= req
->async_data
;
3418 /* it's copied and will be cleaned with ->io */
3420 /* now use our persistent iterator, if we aren't already */
3423 rw
->bytes_done
+= ret
;
3424 /* if we can retry, do so with the callbacks armed */
3425 if (!io_rw_should_retry(req
)) {
3426 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3431 * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
3432 * get -EIOCBQUEUED, then we'll get a notification when the desired
3433 * page gets unlocked. We can also get a partial read here, and if we
3434 * do, then just retry at the new offset.
3436 ret
= io_iter_do_read(req
, iter
);
3437 if (ret
== -EIOCBQUEUED
) {
3440 } else if (ret
> 0 && ret
< io_size
) {
3441 /* we got some bytes, but not all. retry. */
3445 kiocb_done(kiocb
, ret
, cs
);
3448 /* it's reportedly faster than delegating the null check to kfree() */
3454 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3458 ret
= io_prep_rw(req
, sqe
);
3462 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3465 /* either don't need iovec imported or already have it */
3466 if (!req
->async_data
)
3468 return io_rw_prep_async(req
, WRITE
);
3471 static int io_write(struct io_kiocb
*req
, bool force_nonblock
,
3472 struct io_comp_state
*cs
)
3474 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3475 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3476 struct iov_iter __iter
, *iter
= &__iter
;
3477 struct io_async_rw
*rw
= req
->async_data
;
3479 ssize_t ret
, ret2
, io_size
;
3484 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3487 iov_count
= iov_iter_count(iter
);
3489 req
->result
= io_size
;
3491 /* Ensure we clear previously set non-block flag */
3492 if (!force_nonblock
)
3493 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3495 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3497 /* If the file doesn't support async, just async punt */
3498 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3501 /* file path doesn't support NOWAIT for non-direct_IO */
3502 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3503 (req
->flags
& REQ_F_ISREG
))
3506 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), iov_count
);
3511 * Open-code file_start_write here to grab freeze protection,
3512 * which will be released by another thread in
3513 * io_complete_rw(). Fool lockdep by telling it the lock got
3514 * released so that it doesn't complain about the held lock when
3515 * we return to userspace.
3517 if (req
->flags
& REQ_F_ISREG
) {
3518 __sb_start_write(file_inode(req
->file
)->i_sb
,
3519 SB_FREEZE_WRITE
, true);
3520 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3523 kiocb
->ki_flags
|= IOCB_WRITE
;
3525 if (req
->file
->f_op
->write_iter
)
3526 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3527 else if (req
->file
->f_op
->write
)
3528 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3533 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3534 * retry them without IOCB_NOWAIT.
3536 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3538 /* no retry on NONBLOCK marked file */
3539 if (ret2
== -EAGAIN
&& (req
->file
->f_flags
& O_NONBLOCK
))
3541 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3542 /* IOPOLL retry should happen for io-wq threads */
3543 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3546 kiocb_done(kiocb
, ret2
, cs
);
3549 /* some cases will consume bytes even on error returns */
3550 iov_iter_revert(iter
, iov_count
- iov_iter_count(iter
));
3551 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3556 /* it's reportedly faster than delegating the null check to kfree() */
3562 static int __io_splice_prep(struct io_kiocb
*req
,
3563 const struct io_uring_sqe
*sqe
)
3565 struct io_splice
* sp
= &req
->splice
;
3566 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3568 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3572 sp
->len
= READ_ONCE(sqe
->len
);
3573 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3575 if (unlikely(sp
->flags
& ~valid_flags
))
3578 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3579 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3582 req
->flags
|= REQ_F_NEED_CLEANUP
;
3584 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3586 * Splice operation will be punted aync, and here need to
3587 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3589 io_req_init_async(req
);
3590 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3596 static int io_tee_prep(struct io_kiocb
*req
,
3597 const struct io_uring_sqe
*sqe
)
3599 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3601 return __io_splice_prep(req
, sqe
);
3604 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
3606 struct io_splice
*sp
= &req
->splice
;
3607 struct file
*in
= sp
->file_in
;
3608 struct file
*out
= sp
->file_out
;
3609 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3615 ret
= do_tee(in
, out
, sp
->len
, flags
);
3617 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3618 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3621 req_set_fail_links(req
);
3622 io_req_complete(req
, ret
);
3626 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3628 struct io_splice
* sp
= &req
->splice
;
3630 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3631 sp
->off_out
= READ_ONCE(sqe
->off
);
3632 return __io_splice_prep(req
, sqe
);
3635 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
3637 struct io_splice
*sp
= &req
->splice
;
3638 struct file
*in
= sp
->file_in
;
3639 struct file
*out
= sp
->file_out
;
3640 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3641 loff_t
*poff_in
, *poff_out
;
3647 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3648 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3651 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3653 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3654 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3657 req_set_fail_links(req
);
3658 io_req_complete(req
, ret
);
3663 * IORING_OP_NOP just posts a completion event, nothing else.
3665 static int io_nop(struct io_kiocb
*req
, struct io_comp_state
*cs
)
3667 struct io_ring_ctx
*ctx
= req
->ctx
;
3669 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3672 __io_req_complete(req
, 0, 0, cs
);
3676 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3678 struct io_ring_ctx
*ctx
= req
->ctx
;
3683 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3685 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3688 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3689 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3692 req
->sync
.off
= READ_ONCE(sqe
->off
);
3693 req
->sync
.len
= READ_ONCE(sqe
->len
);
3697 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
3699 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3702 /* fsync always requires a blocking context */
3706 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3707 end
> 0 ? end
: LLONG_MAX
,
3708 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3710 req_set_fail_links(req
);
3711 io_req_complete(req
, ret
);
3715 static int io_fallocate_prep(struct io_kiocb
*req
,
3716 const struct io_uring_sqe
*sqe
)
3718 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3720 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3723 req
->sync
.off
= READ_ONCE(sqe
->off
);
3724 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3725 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3729 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
3733 /* fallocate always requiring blocking context */
3736 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3739 req_set_fail_links(req
);
3740 io_req_complete(req
, ret
);
3744 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3746 const char __user
*fname
;
3749 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3751 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3754 /* open.how should be already initialised */
3755 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3756 req
->open
.how
.flags
|= O_LARGEFILE
;
3758 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3759 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3760 req
->open
.filename
= getname(fname
);
3761 if (IS_ERR(req
->open
.filename
)) {
3762 ret
= PTR_ERR(req
->open
.filename
);
3763 req
->open
.filename
= NULL
;
3766 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3767 req
->flags
|= REQ_F_NEED_CLEANUP
;
3771 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3775 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3777 mode
= READ_ONCE(sqe
->len
);
3778 flags
= READ_ONCE(sqe
->open_flags
);
3779 req
->open
.how
= build_open_how(flags
, mode
);
3780 return __io_openat_prep(req
, sqe
);
3783 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3785 struct open_how __user
*how
;
3789 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3791 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3792 len
= READ_ONCE(sqe
->len
);
3793 if (len
< OPEN_HOW_SIZE_VER0
)
3796 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3801 return __io_openat_prep(req
, sqe
);
3804 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
3806 struct open_flags op
;
3813 ret
= build_open_flags(&req
->open
.how
, &op
);
3817 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3821 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3824 ret
= PTR_ERR(file
);
3826 fsnotify_open(file
);
3827 fd_install(ret
, file
);
3830 putname(req
->open
.filename
);
3831 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3833 req_set_fail_links(req
);
3834 io_req_complete(req
, ret
);
3838 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
3840 return io_openat2(req
, force_nonblock
);
3843 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3844 const struct io_uring_sqe
*sqe
)
3846 struct io_provide_buf
*p
= &req
->pbuf
;
3849 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3852 tmp
= READ_ONCE(sqe
->fd
);
3853 if (!tmp
|| tmp
> USHRT_MAX
)
3856 memset(p
, 0, sizeof(*p
));
3858 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3862 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3863 int bgid
, unsigned nbufs
)
3867 /* shouldn't happen */
3871 /* the head kbuf is the list itself */
3872 while (!list_empty(&buf
->list
)) {
3873 struct io_buffer
*nxt
;
3875 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3876 list_del(&nxt
->list
);
3883 idr_remove(&ctx
->io_buffer_idr
, bgid
);
3888 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3889 struct io_comp_state
*cs
)
3891 struct io_provide_buf
*p
= &req
->pbuf
;
3892 struct io_ring_ctx
*ctx
= req
->ctx
;
3893 struct io_buffer
*head
;
3896 io_ring_submit_lock(ctx
, !force_nonblock
);
3898 lockdep_assert_held(&ctx
->uring_lock
);
3901 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3903 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3905 io_ring_submit_lock(ctx
, !force_nonblock
);
3907 req_set_fail_links(req
);
3908 __io_req_complete(req
, ret
, 0, cs
);
3912 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3913 const struct io_uring_sqe
*sqe
)
3915 struct io_provide_buf
*p
= &req
->pbuf
;
3918 if (sqe
->ioprio
|| sqe
->rw_flags
)
3921 tmp
= READ_ONCE(sqe
->fd
);
3922 if (!tmp
|| tmp
> USHRT_MAX
)
3925 p
->addr
= READ_ONCE(sqe
->addr
);
3926 p
->len
= READ_ONCE(sqe
->len
);
3928 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
3931 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3932 tmp
= READ_ONCE(sqe
->off
);
3933 if (tmp
> USHRT_MAX
)
3939 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3941 struct io_buffer
*buf
;
3942 u64 addr
= pbuf
->addr
;
3943 int i
, bid
= pbuf
->bid
;
3945 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3946 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3951 buf
->len
= pbuf
->len
;
3956 INIT_LIST_HEAD(&buf
->list
);
3959 list_add_tail(&buf
->list
, &(*head
)->list
);
3963 return i
? i
: -ENOMEM
;
3966 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3967 struct io_comp_state
*cs
)
3969 struct io_provide_buf
*p
= &req
->pbuf
;
3970 struct io_ring_ctx
*ctx
= req
->ctx
;
3971 struct io_buffer
*head
, *list
;
3974 io_ring_submit_lock(ctx
, !force_nonblock
);
3976 lockdep_assert_held(&ctx
->uring_lock
);
3978 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3980 ret
= io_add_buffers(p
, &head
);
3985 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
3988 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
3993 io_ring_submit_unlock(ctx
, !force_nonblock
);
3995 req_set_fail_links(req
);
3996 __io_req_complete(req
, ret
, 0, cs
);
4000 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4001 const struct io_uring_sqe
*sqe
)
4003 #if defined(CONFIG_EPOLL)
4004 if (sqe
->ioprio
|| sqe
->buf_index
)
4006 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4009 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4010 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4011 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4013 if (ep_op_has_event(req
->epoll
.op
)) {
4014 struct epoll_event __user
*ev
;
4016 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4017 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4027 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
,
4028 struct io_comp_state
*cs
)
4030 #if defined(CONFIG_EPOLL)
4031 struct io_epoll
*ie
= &req
->epoll
;
4034 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4035 if (force_nonblock
&& ret
== -EAGAIN
)
4039 req_set_fail_links(req
);
4040 __io_req_complete(req
, ret
, 0, cs
);
4047 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4049 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4050 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4052 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4055 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4056 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4057 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4064 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
4066 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4067 struct io_madvise
*ma
= &req
->madvise
;
4073 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4075 req_set_fail_links(req
);
4076 io_req_complete(req
, ret
);
4083 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4085 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4087 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4090 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4091 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4092 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4096 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
4098 struct io_fadvise
*fa
= &req
->fadvise
;
4101 if (force_nonblock
) {
4102 switch (fa
->advice
) {
4103 case POSIX_FADV_NORMAL
:
4104 case POSIX_FADV_RANDOM
:
4105 case POSIX_FADV_SEQUENTIAL
:
4112 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4114 req_set_fail_links(req
);
4115 io_req_complete(req
, ret
);
4119 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4121 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4123 if (sqe
->ioprio
|| sqe
->buf_index
)
4125 if (req
->flags
& REQ_F_FIXED_FILE
)
4128 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4129 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4130 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4131 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4132 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4137 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
4139 struct io_statx
*ctx
= &req
->statx
;
4142 if (force_nonblock
) {
4143 /* only need file table for an actual valid fd */
4144 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
4145 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4149 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4153 req_set_fail_links(req
);
4154 io_req_complete(req
, ret
);
4158 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4161 * If we queue this for async, it must not be cancellable. That would
4162 * leave the 'file' in an undeterminate state, and here need to modify
4163 * io_wq_work.flags, so initialize io_wq_work firstly.
4165 io_req_init_async(req
);
4166 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
4168 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4170 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4171 sqe
->rw_flags
|| sqe
->buf_index
)
4173 if (req
->flags
& REQ_F_FIXED_FILE
)
4176 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4177 if ((req
->file
&& req
->file
->f_op
== &io_uring_fops
))
4180 req
->close
.put_file
= NULL
;
4184 static int io_close(struct io_kiocb
*req
, bool force_nonblock
,
4185 struct io_comp_state
*cs
)
4187 struct io_close
*close
= &req
->close
;
4190 /* might be already done during nonblock submission */
4191 if (!close
->put_file
) {
4192 ret
= __close_fd_get_file(close
->fd
, &close
->put_file
);
4194 return (ret
== -ENOENT
) ? -EBADF
: ret
;
4197 /* if the file has a flush method, be safe and punt to async */
4198 if (close
->put_file
->f_op
->flush
&& force_nonblock
) {
4199 /* was never set, but play safe */
4200 req
->flags
&= ~REQ_F_NOWAIT
;
4201 /* avoid grabbing files - we don't need the files */
4202 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4206 /* No ->flush() or already async, safely close from here */
4207 ret
= filp_close(close
->put_file
, req
->work
.identity
->files
);
4209 req_set_fail_links(req
);
4210 fput(close
->put_file
);
4211 close
->put_file
= NULL
;
4212 __io_req_complete(req
, ret
, 0, cs
);
4216 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4218 struct io_ring_ctx
*ctx
= req
->ctx
;
4223 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4225 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4228 req
->sync
.off
= READ_ONCE(sqe
->off
);
4229 req
->sync
.len
= READ_ONCE(sqe
->len
);
4230 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4234 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
4238 /* sync_file_range always requires a blocking context */
4242 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4245 req_set_fail_links(req
);
4246 io_req_complete(req
, ret
);
4250 #if defined(CONFIG_NET)
4251 static int io_setup_async_msg(struct io_kiocb
*req
,
4252 struct io_async_msghdr
*kmsg
)
4254 struct io_async_msghdr
*async_msg
= req
->async_data
;
4258 if (io_alloc_async_data(req
)) {
4259 if (kmsg
->iov
!= kmsg
->fast_iov
)
4263 async_msg
= req
->async_data
;
4264 req
->flags
|= REQ_F_NEED_CLEANUP
;
4265 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4269 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4270 struct io_async_msghdr
*iomsg
)
4272 iomsg
->iov
= iomsg
->fast_iov
;
4273 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4274 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4275 req
->sr_msg
.msg_flags
, &iomsg
->iov
);
4278 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4280 struct io_async_msghdr
*async_msg
= req
->async_data
;
4281 struct io_sr_msg
*sr
= &req
->sr_msg
;
4284 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4287 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4288 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4289 sr
->len
= READ_ONCE(sqe
->len
);
4291 #ifdef CONFIG_COMPAT
4292 if (req
->ctx
->compat
)
4293 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4296 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4298 ret
= io_sendmsg_copy_hdr(req
, async_msg
);
4300 req
->flags
|= REQ_F_NEED_CLEANUP
;
4304 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4305 struct io_comp_state
*cs
)
4307 struct io_async_msghdr iomsg
, *kmsg
;
4308 struct socket
*sock
;
4312 sock
= sock_from_file(req
->file
, &ret
);
4313 if (unlikely(!sock
))
4316 if (req
->async_data
) {
4317 kmsg
= req
->async_data
;
4318 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4319 /* if iov is set, it's allocated already */
4321 kmsg
->iov
= kmsg
->fast_iov
;
4322 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4324 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4330 flags
= req
->sr_msg
.msg_flags
;
4331 if (flags
& MSG_DONTWAIT
)
4332 req
->flags
|= REQ_F_NOWAIT
;
4333 else if (force_nonblock
)
4334 flags
|= MSG_DONTWAIT
;
4336 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4337 if (force_nonblock
&& ret
== -EAGAIN
)
4338 return io_setup_async_msg(req
, kmsg
);
4339 if (ret
== -ERESTARTSYS
)
4342 if (kmsg
->iov
!= kmsg
->fast_iov
)
4344 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4346 req_set_fail_links(req
);
4347 __io_req_complete(req
, ret
, 0, cs
);
4351 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4352 struct io_comp_state
*cs
)
4354 struct io_sr_msg
*sr
= &req
->sr_msg
;
4357 struct socket
*sock
;
4361 sock
= sock_from_file(req
->file
, &ret
);
4362 if (unlikely(!sock
))
4365 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4369 msg
.msg_name
= NULL
;
4370 msg
.msg_control
= NULL
;
4371 msg
.msg_controllen
= 0;
4372 msg
.msg_namelen
= 0;
4374 flags
= req
->sr_msg
.msg_flags
;
4375 if (flags
& MSG_DONTWAIT
)
4376 req
->flags
|= REQ_F_NOWAIT
;
4377 else if (force_nonblock
)
4378 flags
|= MSG_DONTWAIT
;
4380 msg
.msg_flags
= flags
;
4381 ret
= sock_sendmsg(sock
, &msg
);
4382 if (force_nonblock
&& ret
== -EAGAIN
)
4384 if (ret
== -ERESTARTSYS
)
4388 req_set_fail_links(req
);
4389 __io_req_complete(req
, ret
, 0, cs
);
4393 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4394 struct io_async_msghdr
*iomsg
)
4396 struct io_sr_msg
*sr
= &req
->sr_msg
;
4397 struct iovec __user
*uiov
;
4401 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4402 &iomsg
->uaddr
, &uiov
, &iov_len
);
4406 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4409 if (copy_from_user(iomsg
->iov
, uiov
, sizeof(*uiov
)))
4411 sr
->len
= iomsg
->iov
[0].iov_len
;
4412 iov_iter_init(&iomsg
->msg
.msg_iter
, READ
, iomsg
->iov
, 1,
4416 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4417 &iomsg
->iov
, &iomsg
->msg
.msg_iter
,
4426 #ifdef CONFIG_COMPAT
4427 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4428 struct io_async_msghdr
*iomsg
)
4430 struct compat_msghdr __user
*msg_compat
;
4431 struct io_sr_msg
*sr
= &req
->sr_msg
;
4432 struct compat_iovec __user
*uiov
;
4437 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4438 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4443 uiov
= compat_ptr(ptr
);
4444 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4445 compat_ssize_t clen
;
4449 if (!access_ok(uiov
, sizeof(*uiov
)))
4451 if (__get_user(clen
, &uiov
->iov_len
))
4455 sr
->len
= iomsg
->iov
[0].iov_len
;
4458 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4459 UIO_FASTIOV
, &iomsg
->iov
,
4460 &iomsg
->msg
.msg_iter
, true);
4469 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4470 struct io_async_msghdr
*iomsg
)
4472 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4473 iomsg
->iov
= iomsg
->fast_iov
;
4475 #ifdef CONFIG_COMPAT
4476 if (req
->ctx
->compat
)
4477 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4480 return __io_recvmsg_copy_hdr(req
, iomsg
);
4483 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4486 struct io_sr_msg
*sr
= &req
->sr_msg
;
4487 struct io_buffer
*kbuf
;
4489 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4494 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4498 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4500 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4503 static int io_recvmsg_prep(struct io_kiocb
*req
,
4504 const struct io_uring_sqe
*sqe
)
4506 struct io_async_msghdr
*async_msg
= req
->async_data
;
4507 struct io_sr_msg
*sr
= &req
->sr_msg
;
4510 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4513 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4514 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4515 sr
->len
= READ_ONCE(sqe
->len
);
4516 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4518 #ifdef CONFIG_COMPAT
4519 if (req
->ctx
->compat
)
4520 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4523 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4525 ret
= io_recvmsg_copy_hdr(req
, async_msg
);
4527 req
->flags
|= REQ_F_NEED_CLEANUP
;
4531 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4532 struct io_comp_state
*cs
)
4534 struct io_async_msghdr iomsg
, *kmsg
;
4535 struct socket
*sock
;
4536 struct io_buffer
*kbuf
;
4538 int ret
, cflags
= 0;
4540 sock
= sock_from_file(req
->file
, &ret
);
4541 if (unlikely(!sock
))
4544 if (req
->async_data
) {
4545 kmsg
= req
->async_data
;
4546 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4547 /* if iov is set, it's allocated already */
4549 kmsg
->iov
= kmsg
->fast_iov
;
4550 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4552 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4558 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4559 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4561 return PTR_ERR(kbuf
);
4562 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4563 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
4564 1, req
->sr_msg
.len
);
4567 flags
= req
->sr_msg
.msg_flags
;
4568 if (flags
& MSG_DONTWAIT
)
4569 req
->flags
|= REQ_F_NOWAIT
;
4570 else if (force_nonblock
)
4571 flags
|= MSG_DONTWAIT
;
4573 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4574 kmsg
->uaddr
, flags
);
4575 if (force_nonblock
&& ret
== -EAGAIN
)
4576 return io_setup_async_msg(req
, kmsg
);
4577 if (ret
== -ERESTARTSYS
)
4580 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4581 cflags
= io_put_recv_kbuf(req
);
4582 if (kmsg
->iov
!= kmsg
->fast_iov
)
4584 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4586 req_set_fail_links(req
);
4587 __io_req_complete(req
, ret
, cflags
, cs
);
4591 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4592 struct io_comp_state
*cs
)
4594 struct io_buffer
*kbuf
;
4595 struct io_sr_msg
*sr
= &req
->sr_msg
;
4597 void __user
*buf
= sr
->buf
;
4598 struct socket
*sock
;
4601 int ret
, cflags
= 0;
4603 sock
= sock_from_file(req
->file
, &ret
);
4604 if (unlikely(!sock
))
4607 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4608 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4610 return PTR_ERR(kbuf
);
4611 buf
= u64_to_user_ptr(kbuf
->addr
);
4614 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4618 msg
.msg_name
= NULL
;
4619 msg
.msg_control
= NULL
;
4620 msg
.msg_controllen
= 0;
4621 msg
.msg_namelen
= 0;
4622 msg
.msg_iocb
= NULL
;
4625 flags
= req
->sr_msg
.msg_flags
;
4626 if (flags
& MSG_DONTWAIT
)
4627 req
->flags
|= REQ_F_NOWAIT
;
4628 else if (force_nonblock
)
4629 flags
|= MSG_DONTWAIT
;
4631 ret
= sock_recvmsg(sock
, &msg
, flags
);
4632 if (force_nonblock
&& ret
== -EAGAIN
)
4634 if (ret
== -ERESTARTSYS
)
4637 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4638 cflags
= io_put_recv_kbuf(req
);
4640 req_set_fail_links(req
);
4641 __io_req_complete(req
, ret
, cflags
, cs
);
4645 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4647 struct io_accept
*accept
= &req
->accept
;
4649 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4651 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4654 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4655 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4656 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4657 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4661 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4662 struct io_comp_state
*cs
)
4664 struct io_accept
*accept
= &req
->accept
;
4665 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4668 if (req
->file
->f_flags
& O_NONBLOCK
)
4669 req
->flags
|= REQ_F_NOWAIT
;
4671 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4672 accept
->addr_len
, accept
->flags
,
4674 if (ret
== -EAGAIN
&& force_nonblock
)
4677 if (ret
== -ERESTARTSYS
)
4679 req_set_fail_links(req
);
4681 __io_req_complete(req
, ret
, 0, cs
);
4685 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4687 struct io_connect
*conn
= &req
->connect
;
4688 struct io_async_connect
*io
= req
->async_data
;
4690 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4692 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4695 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4696 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4701 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4705 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4706 struct io_comp_state
*cs
)
4708 struct io_async_connect __io
, *io
;
4709 unsigned file_flags
;
4712 if (req
->async_data
) {
4713 io
= req
->async_data
;
4715 ret
= move_addr_to_kernel(req
->connect
.addr
,
4716 req
->connect
.addr_len
,
4723 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4725 ret
= __sys_connect_file(req
->file
, &io
->address
,
4726 req
->connect
.addr_len
, file_flags
);
4727 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4728 if (req
->async_data
)
4730 if (io_alloc_async_data(req
)) {
4734 io
= req
->async_data
;
4735 memcpy(req
->async_data
, &__io
, sizeof(__io
));
4738 if (ret
== -ERESTARTSYS
)
4742 req_set_fail_links(req
);
4743 __io_req_complete(req
, ret
, 0, cs
);
4746 #else /* !CONFIG_NET */
4747 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4752 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4753 struct io_comp_state
*cs
)
4758 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4759 struct io_comp_state
*cs
)
4764 static int io_recvmsg_prep(struct io_kiocb
*req
,
4765 const struct io_uring_sqe
*sqe
)
4770 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4771 struct io_comp_state
*cs
)
4776 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4777 struct io_comp_state
*cs
)
4782 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4787 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4788 struct io_comp_state
*cs
)
4793 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4798 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4799 struct io_comp_state
*cs
)
4803 #endif /* CONFIG_NET */
4805 struct io_poll_table
{
4806 struct poll_table_struct pt
;
4807 struct io_kiocb
*req
;
4811 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4812 __poll_t mask
, task_work_func_t func
)
4817 /* for instances that support it check for an event match first: */
4818 if (mask
&& !(mask
& poll
->events
))
4821 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4823 list_del_init(&poll
->wait
.entry
);
4826 init_task_work(&req
->task_work
, func
);
4827 percpu_ref_get(&req
->ctx
->refs
);
4830 * If we using the signalfd wait_queue_head for this wakeup, then
4831 * it's not safe to use TWA_SIGNAL as we could be recursing on the
4832 * tsk->sighand->siglock on doing the wakeup. Should not be needed
4833 * either, as the normal wakeup will suffice.
4835 twa_signal_ok
= (poll
->head
!= &req
->task
->sighand
->signalfd_wqh
);
4838 * If this fails, then the task is exiting. When a task exits, the
4839 * work gets canceled, so just cancel this request as well instead
4840 * of executing it. We can't safely execute it anyway, as we may not
4841 * have the needed state needed for it anyway.
4843 ret
= io_req_task_work_add(req
, twa_signal_ok
);
4844 if (unlikely(ret
)) {
4845 struct task_struct
*tsk
;
4847 WRITE_ONCE(poll
->canceled
, true);
4848 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
4849 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
4850 wake_up_process(tsk
);
4855 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4856 __acquires(&req
->ctx
->completion_lock
)
4858 struct io_ring_ctx
*ctx
= req
->ctx
;
4860 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4861 struct poll_table_struct pt
= { ._key
= poll
->events
};
4863 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4866 spin_lock_irq(&ctx
->completion_lock
);
4867 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4868 add_wait_queue(poll
->head
, &poll
->wait
);
4875 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
4877 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
4878 if (req
->opcode
== IORING_OP_POLL_ADD
)
4879 return req
->async_data
;
4880 return req
->apoll
->double_poll
;
4883 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
4885 if (req
->opcode
== IORING_OP_POLL_ADD
)
4887 return &req
->apoll
->poll
;
4890 static void io_poll_remove_double(struct io_kiocb
*req
)
4892 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
4894 lockdep_assert_held(&req
->ctx
->completion_lock
);
4896 if (poll
&& poll
->head
) {
4897 struct wait_queue_head
*head
= poll
->head
;
4899 spin_lock(&head
->lock
);
4900 list_del_init(&poll
->wait
.entry
);
4901 if (poll
->wait
.private)
4902 refcount_dec(&req
->refs
);
4904 spin_unlock(&head
->lock
);
4908 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4910 struct io_ring_ctx
*ctx
= req
->ctx
;
4912 io_poll_remove_double(req
);
4913 req
->poll
.done
= true;
4914 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
4915 io_commit_cqring(ctx
);
4918 static void io_poll_task_func(struct callback_head
*cb
)
4920 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4921 struct io_ring_ctx
*ctx
= req
->ctx
;
4922 struct io_kiocb
*nxt
;
4924 if (io_poll_rewait(req
, &req
->poll
)) {
4925 spin_unlock_irq(&ctx
->completion_lock
);
4927 hash_del(&req
->hash_node
);
4928 io_poll_complete(req
, req
->result
, 0);
4929 spin_unlock_irq(&ctx
->completion_lock
);
4931 nxt
= io_put_req_find_next(req
);
4932 io_cqring_ev_posted(ctx
);
4934 __io_req_task_submit(nxt
);
4937 percpu_ref_put(&ctx
->refs
);
4940 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4941 int sync
, void *key
)
4943 struct io_kiocb
*req
= wait
->private;
4944 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
4945 __poll_t mask
= key_to_poll(key
);
4947 /* for instances that support it check for an event match first: */
4948 if (mask
&& !(mask
& poll
->events
))
4951 list_del_init(&wait
->entry
);
4953 if (poll
&& poll
->head
) {
4956 spin_lock(&poll
->head
->lock
);
4957 done
= list_empty(&poll
->wait
.entry
);
4959 list_del_init(&poll
->wait
.entry
);
4960 /* make sure double remove sees this as being gone */
4961 wait
->private = NULL
;
4962 spin_unlock(&poll
->head
->lock
);
4964 /* use wait func handler, so it matches the rq type */
4965 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
4968 refcount_dec(&req
->refs
);
4972 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
4973 wait_queue_func_t wake_func
)
4977 poll
->canceled
= false;
4978 poll
->events
= events
;
4979 INIT_LIST_HEAD(&poll
->wait
.entry
);
4980 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
4983 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
4984 struct wait_queue_head
*head
,
4985 struct io_poll_iocb
**poll_ptr
)
4987 struct io_kiocb
*req
= pt
->req
;
4990 * If poll->head is already set, it's because the file being polled
4991 * uses multiple waitqueues for poll handling (eg one for read, one
4992 * for write). Setup a separate io_poll_iocb if this happens.
4994 if (unlikely(poll
->head
)) {
4995 struct io_poll_iocb
*poll_one
= poll
;
4997 /* already have a 2nd entry, fail a third attempt */
4999 pt
->error
= -EINVAL
;
5002 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5004 pt
->error
= -ENOMEM
;
5007 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5008 refcount_inc(&req
->refs
);
5009 poll
->wait
.private = req
;
5016 if (poll
->events
& EPOLLEXCLUSIVE
)
5017 add_wait_queue_exclusive(head
, &poll
->wait
);
5019 add_wait_queue(head
, &poll
->wait
);
5022 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5023 struct poll_table_struct
*p
)
5025 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5026 struct async_poll
*apoll
= pt
->req
->apoll
;
5028 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5031 static void io_async_task_func(struct callback_head
*cb
)
5033 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5034 struct async_poll
*apoll
= req
->apoll
;
5035 struct io_ring_ctx
*ctx
= req
->ctx
;
5037 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5039 if (io_poll_rewait(req
, &apoll
->poll
)) {
5040 spin_unlock_irq(&ctx
->completion_lock
);
5041 percpu_ref_put(&ctx
->refs
);
5045 /* If req is still hashed, it cannot have been canceled. Don't check. */
5046 if (hash_hashed(&req
->hash_node
))
5047 hash_del(&req
->hash_node
);
5049 io_poll_remove_double(req
);
5050 spin_unlock_irq(&ctx
->completion_lock
);
5052 if (!READ_ONCE(apoll
->poll
.canceled
))
5053 __io_req_task_submit(req
);
5055 __io_req_task_cancel(req
, -ECANCELED
);
5057 percpu_ref_put(&ctx
->refs
);
5058 kfree(apoll
->double_poll
);
5062 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5065 struct io_kiocb
*req
= wait
->private;
5066 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5068 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5071 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5074 static void io_poll_req_insert(struct io_kiocb
*req
)
5076 struct io_ring_ctx
*ctx
= req
->ctx
;
5077 struct hlist_head
*list
;
5079 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5080 hlist_add_head(&req
->hash_node
, list
);
5083 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5084 struct io_poll_iocb
*poll
,
5085 struct io_poll_table
*ipt
, __poll_t mask
,
5086 wait_queue_func_t wake_func
)
5087 __acquires(&ctx
->completion_lock
)
5089 struct io_ring_ctx
*ctx
= req
->ctx
;
5090 bool cancel
= false;
5092 INIT_HLIST_NODE(&req
->hash_node
);
5093 io_init_poll_iocb(poll
, mask
, wake_func
);
5094 poll
->file
= req
->file
;
5095 poll
->wait
.private = req
;
5097 ipt
->pt
._key
= mask
;
5099 ipt
->error
= -EINVAL
;
5101 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5103 spin_lock_irq(&ctx
->completion_lock
);
5104 if (likely(poll
->head
)) {
5105 spin_lock(&poll
->head
->lock
);
5106 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5112 if (mask
|| ipt
->error
)
5113 list_del_init(&poll
->wait
.entry
);
5115 WRITE_ONCE(poll
->canceled
, true);
5116 else if (!poll
->done
) /* actually waiting for an event */
5117 io_poll_req_insert(req
);
5118 spin_unlock(&poll
->head
->lock
);
5124 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5126 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5127 struct io_ring_ctx
*ctx
= req
->ctx
;
5128 struct async_poll
*apoll
;
5129 struct io_poll_table ipt
;
5133 if (!req
->file
|| !file_can_poll(req
->file
))
5135 if (req
->flags
& REQ_F_POLLED
)
5139 else if (def
->pollout
)
5143 /* if we can't nonblock try, then no point in arming a poll handler */
5144 if (!io_file_supports_async(req
->file
, rw
))
5147 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5148 if (unlikely(!apoll
))
5150 apoll
->double_poll
= NULL
;
5152 req
->flags
|= REQ_F_POLLED
;
5157 mask
|= POLLIN
| POLLRDNORM
;
5159 mask
|= POLLOUT
| POLLWRNORM
;
5161 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5162 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5163 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5166 mask
|= POLLERR
| POLLPRI
;
5168 ipt
.pt
._qproc
= io_async_queue_proc
;
5170 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5172 if (ret
|| ipt
.error
) {
5173 io_poll_remove_double(req
);
5174 spin_unlock_irq(&ctx
->completion_lock
);
5175 kfree(apoll
->double_poll
);
5179 spin_unlock_irq(&ctx
->completion_lock
);
5180 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5181 apoll
->poll
.events
);
5185 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5186 struct io_poll_iocb
*poll
)
5188 bool do_complete
= false;
5190 spin_lock(&poll
->head
->lock
);
5191 WRITE_ONCE(poll
->canceled
, true);
5192 if (!list_empty(&poll
->wait
.entry
)) {
5193 list_del_init(&poll
->wait
.entry
);
5196 spin_unlock(&poll
->head
->lock
);
5197 hash_del(&req
->hash_node
);
5201 static bool io_poll_remove_one(struct io_kiocb
*req
)
5205 io_poll_remove_double(req
);
5207 if (req
->opcode
== IORING_OP_POLL_ADD
) {
5208 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
5210 struct async_poll
*apoll
= req
->apoll
;
5212 /* non-poll requests have submit ref still */
5213 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
5216 kfree(apoll
->double_poll
);
5222 io_cqring_fill_event(req
, -ECANCELED
);
5223 io_commit_cqring(req
->ctx
);
5224 req_set_fail_links(req
);
5225 io_put_req_deferred(req
, 1);
5232 * Returns true if we found and killed one or more poll requests
5234 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
)
5236 struct hlist_node
*tmp
;
5237 struct io_kiocb
*req
;
5240 spin_lock_irq(&ctx
->completion_lock
);
5241 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5242 struct hlist_head
*list
;
5244 list
= &ctx
->cancel_hash
[i
];
5245 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5246 if (io_task_match(req
, tsk
))
5247 posted
+= io_poll_remove_one(req
);
5250 spin_unlock_irq(&ctx
->completion_lock
);
5253 io_cqring_ev_posted(ctx
);
5258 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5260 struct hlist_head
*list
;
5261 struct io_kiocb
*req
;
5263 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5264 hlist_for_each_entry(req
, list
, hash_node
) {
5265 if (sqe_addr
!= req
->user_data
)
5267 if (io_poll_remove_one(req
))
5275 static int io_poll_remove_prep(struct io_kiocb
*req
,
5276 const struct io_uring_sqe
*sqe
)
5278 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5280 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5284 req
->poll
.addr
= READ_ONCE(sqe
->addr
);
5289 * Find a running poll command that matches one specified in sqe->addr,
5290 * and remove it if found.
5292 static int io_poll_remove(struct io_kiocb
*req
)
5294 struct io_ring_ctx
*ctx
= req
->ctx
;
5298 addr
= req
->poll
.addr
;
5299 spin_lock_irq(&ctx
->completion_lock
);
5300 ret
= io_poll_cancel(ctx
, addr
);
5301 spin_unlock_irq(&ctx
->completion_lock
);
5304 req_set_fail_links(req
);
5305 io_req_complete(req
, ret
);
5309 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5312 struct io_kiocb
*req
= wait
->private;
5313 struct io_poll_iocb
*poll
= &req
->poll
;
5315 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5318 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5319 struct poll_table_struct
*p
)
5321 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5323 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5326 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5328 struct io_poll_iocb
*poll
= &req
->poll
;
5331 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5333 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
5336 events
= READ_ONCE(sqe
->poll32_events
);
5338 events
= swahw32(events
);
5340 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
5341 (events
& EPOLLEXCLUSIVE
);
5345 static int io_poll_add(struct io_kiocb
*req
)
5347 struct io_poll_iocb
*poll
= &req
->poll
;
5348 struct io_ring_ctx
*ctx
= req
->ctx
;
5349 struct io_poll_table ipt
;
5352 ipt
.pt
._qproc
= io_poll_queue_proc
;
5354 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5357 if (mask
) { /* no async, we'd stolen it */
5359 io_poll_complete(req
, mask
, 0);
5361 spin_unlock_irq(&ctx
->completion_lock
);
5364 io_cqring_ev_posted(ctx
);
5370 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5372 struct io_timeout_data
*data
= container_of(timer
,
5373 struct io_timeout_data
, timer
);
5374 struct io_kiocb
*req
= data
->req
;
5375 struct io_ring_ctx
*ctx
= req
->ctx
;
5376 unsigned long flags
;
5378 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5379 list_del_init(&req
->timeout
.list
);
5380 atomic_set(&req
->ctx
->cq_timeouts
,
5381 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5383 io_cqring_fill_event(req
, -ETIME
);
5384 io_commit_cqring(ctx
);
5385 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5387 io_cqring_ev_posted(ctx
);
5388 req_set_fail_links(req
);
5390 return HRTIMER_NORESTART
;
5393 static int __io_timeout_cancel(struct io_kiocb
*req
)
5395 struct io_timeout_data
*io
= req
->async_data
;
5398 ret
= hrtimer_try_to_cancel(&io
->timer
);
5401 list_del_init(&req
->timeout
.list
);
5403 req_set_fail_links(req
);
5404 io_cqring_fill_event(req
, -ECANCELED
);
5405 io_put_req_deferred(req
, 1);
5409 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5411 struct io_kiocb
*req
;
5414 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5415 if (user_data
== req
->user_data
) {
5424 return __io_timeout_cancel(req
);
5427 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5428 const struct io_uring_sqe
*sqe
)
5430 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5432 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5434 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
|| sqe
->timeout_flags
)
5437 req
->timeout_rem
.addr
= READ_ONCE(sqe
->addr
);
5442 * Remove or update an existing timeout command
5444 static int io_timeout_remove(struct io_kiocb
*req
)
5446 struct io_ring_ctx
*ctx
= req
->ctx
;
5449 spin_lock_irq(&ctx
->completion_lock
);
5450 ret
= io_timeout_cancel(ctx
, req
->timeout_rem
.addr
);
5452 io_cqring_fill_event(req
, ret
);
5453 io_commit_cqring(ctx
);
5454 spin_unlock_irq(&ctx
->completion_lock
);
5455 io_cqring_ev_posted(ctx
);
5457 req_set_fail_links(req
);
5462 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5463 bool is_timeout_link
)
5465 struct io_timeout_data
*data
;
5467 u32 off
= READ_ONCE(sqe
->off
);
5469 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5471 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5473 if (off
&& is_timeout_link
)
5475 flags
= READ_ONCE(sqe
->timeout_flags
);
5476 if (flags
& ~IORING_TIMEOUT_ABS
)
5479 req
->timeout
.off
= off
;
5481 if (!req
->async_data
&& io_alloc_async_data(req
))
5484 data
= req
->async_data
;
5487 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5490 if (flags
& IORING_TIMEOUT_ABS
)
5491 data
->mode
= HRTIMER_MODE_ABS
;
5493 data
->mode
= HRTIMER_MODE_REL
;
5495 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5499 static int io_timeout(struct io_kiocb
*req
)
5501 struct io_ring_ctx
*ctx
= req
->ctx
;
5502 struct io_timeout_data
*data
= req
->async_data
;
5503 struct list_head
*entry
;
5504 u32 tail
, off
= req
->timeout
.off
;
5506 spin_lock_irq(&ctx
->completion_lock
);
5509 * sqe->off holds how many events that need to occur for this
5510 * timeout event to be satisfied. If it isn't set, then this is
5511 * a pure timeout request, sequence isn't used.
5513 if (io_is_timeout_noseq(req
)) {
5514 entry
= ctx
->timeout_list
.prev
;
5518 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5519 req
->timeout
.target_seq
= tail
+ off
;
5522 * Insertion sort, ensuring the first entry in the list is always
5523 * the one we need first.
5525 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5526 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5529 if (io_is_timeout_noseq(nxt
))
5531 /* nxt.seq is behind @tail, otherwise would've been completed */
5532 if (off
>= nxt
->timeout
.target_seq
- tail
)
5536 list_add(&req
->timeout
.list
, entry
);
5537 data
->timer
.function
= io_timeout_fn
;
5538 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5539 spin_unlock_irq(&ctx
->completion_lock
);
5543 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5545 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5547 return req
->user_data
== (unsigned long) data
;
5550 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5552 enum io_wq_cancel cancel_ret
;
5555 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5556 switch (cancel_ret
) {
5557 case IO_WQ_CANCEL_OK
:
5560 case IO_WQ_CANCEL_RUNNING
:
5563 case IO_WQ_CANCEL_NOTFOUND
:
5571 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5572 struct io_kiocb
*req
, __u64 sqe_addr
,
5575 unsigned long flags
;
5578 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5579 if (ret
!= -ENOENT
) {
5580 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5584 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5585 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5588 ret
= io_poll_cancel(ctx
, sqe_addr
);
5592 io_cqring_fill_event(req
, ret
);
5593 io_commit_cqring(ctx
);
5594 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5595 io_cqring_ev_posted(ctx
);
5598 req_set_fail_links(req
);
5602 static int io_async_cancel_prep(struct io_kiocb
*req
,
5603 const struct io_uring_sqe
*sqe
)
5605 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5607 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5609 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5612 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5616 static int io_async_cancel(struct io_kiocb
*req
)
5618 struct io_ring_ctx
*ctx
= req
->ctx
;
5620 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
5624 static int io_files_update_prep(struct io_kiocb
*req
,
5625 const struct io_uring_sqe
*sqe
)
5627 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
5629 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5631 if (sqe
->ioprio
|| sqe
->rw_flags
)
5634 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
5635 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
5636 if (!req
->files_update
.nr_args
)
5638 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
5642 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
,
5643 struct io_comp_state
*cs
)
5645 struct io_ring_ctx
*ctx
= req
->ctx
;
5646 struct io_uring_files_update up
;
5652 up
.offset
= req
->files_update
.offset
;
5653 up
.fds
= req
->files_update
.arg
;
5655 mutex_lock(&ctx
->uring_lock
);
5656 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
5657 mutex_unlock(&ctx
->uring_lock
);
5660 req_set_fail_links(req
);
5661 __io_req_complete(req
, ret
, 0, cs
);
5665 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5667 switch (req
->opcode
) {
5670 case IORING_OP_READV
:
5671 case IORING_OP_READ_FIXED
:
5672 case IORING_OP_READ
:
5673 return io_read_prep(req
, sqe
);
5674 case IORING_OP_WRITEV
:
5675 case IORING_OP_WRITE_FIXED
:
5676 case IORING_OP_WRITE
:
5677 return io_write_prep(req
, sqe
);
5678 case IORING_OP_POLL_ADD
:
5679 return io_poll_add_prep(req
, sqe
);
5680 case IORING_OP_POLL_REMOVE
:
5681 return io_poll_remove_prep(req
, sqe
);
5682 case IORING_OP_FSYNC
:
5683 return io_prep_fsync(req
, sqe
);
5684 case IORING_OP_SYNC_FILE_RANGE
:
5685 return io_prep_sfr(req
, sqe
);
5686 case IORING_OP_SENDMSG
:
5687 case IORING_OP_SEND
:
5688 return io_sendmsg_prep(req
, sqe
);
5689 case IORING_OP_RECVMSG
:
5690 case IORING_OP_RECV
:
5691 return io_recvmsg_prep(req
, sqe
);
5692 case IORING_OP_CONNECT
:
5693 return io_connect_prep(req
, sqe
);
5694 case IORING_OP_TIMEOUT
:
5695 return io_timeout_prep(req
, sqe
, false);
5696 case IORING_OP_TIMEOUT_REMOVE
:
5697 return io_timeout_remove_prep(req
, sqe
);
5698 case IORING_OP_ASYNC_CANCEL
:
5699 return io_async_cancel_prep(req
, sqe
);
5700 case IORING_OP_LINK_TIMEOUT
:
5701 return io_timeout_prep(req
, sqe
, true);
5702 case IORING_OP_ACCEPT
:
5703 return io_accept_prep(req
, sqe
);
5704 case IORING_OP_FALLOCATE
:
5705 return io_fallocate_prep(req
, sqe
);
5706 case IORING_OP_OPENAT
:
5707 return io_openat_prep(req
, sqe
);
5708 case IORING_OP_CLOSE
:
5709 return io_close_prep(req
, sqe
);
5710 case IORING_OP_FILES_UPDATE
:
5711 return io_files_update_prep(req
, sqe
);
5712 case IORING_OP_STATX
:
5713 return io_statx_prep(req
, sqe
);
5714 case IORING_OP_FADVISE
:
5715 return io_fadvise_prep(req
, sqe
);
5716 case IORING_OP_MADVISE
:
5717 return io_madvise_prep(req
, sqe
);
5718 case IORING_OP_OPENAT2
:
5719 return io_openat2_prep(req
, sqe
);
5720 case IORING_OP_EPOLL_CTL
:
5721 return io_epoll_ctl_prep(req
, sqe
);
5722 case IORING_OP_SPLICE
:
5723 return io_splice_prep(req
, sqe
);
5724 case IORING_OP_PROVIDE_BUFFERS
:
5725 return io_provide_buffers_prep(req
, sqe
);
5726 case IORING_OP_REMOVE_BUFFERS
:
5727 return io_remove_buffers_prep(req
, sqe
);
5729 return io_tee_prep(req
, sqe
);
5732 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5737 static int io_req_defer_prep(struct io_kiocb
*req
,
5738 const struct io_uring_sqe
*sqe
)
5742 if (io_alloc_async_data(req
))
5744 return io_req_prep(req
, sqe
);
5747 static u32
io_get_sequence(struct io_kiocb
*req
)
5749 struct io_kiocb
*pos
;
5750 struct io_ring_ctx
*ctx
= req
->ctx
;
5751 u32 total_submitted
, nr_reqs
= 1;
5753 if (req
->flags
& REQ_F_LINK_HEAD
)
5754 list_for_each_entry(pos
, &req
->link_list
, link_list
)
5757 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5758 return total_submitted
- nr_reqs
;
5761 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5763 struct io_ring_ctx
*ctx
= req
->ctx
;
5764 struct io_defer_entry
*de
;
5768 /* Still need defer if there is pending req in defer list. */
5769 if (likely(list_empty_careful(&ctx
->defer_list
) &&
5770 !(req
->flags
& REQ_F_IO_DRAIN
)))
5773 seq
= io_get_sequence(req
);
5774 /* Still a chance to pass the sequence check */
5775 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
5778 if (!req
->async_data
) {
5779 ret
= io_req_defer_prep(req
, sqe
);
5783 io_prep_async_link(req
);
5784 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
5788 spin_lock_irq(&ctx
->completion_lock
);
5789 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
5790 spin_unlock_irq(&ctx
->completion_lock
);
5792 io_queue_async_work(req
);
5793 return -EIOCBQUEUED
;
5796 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5799 list_add_tail(&de
->list
, &ctx
->defer_list
);
5800 spin_unlock_irq(&ctx
->completion_lock
);
5801 return -EIOCBQUEUED
;
5804 static void io_req_drop_files(struct io_kiocb
*req
)
5806 struct io_ring_ctx
*ctx
= req
->ctx
;
5807 unsigned long flags
;
5809 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
5810 list_del(&req
->inflight_entry
);
5811 if (waitqueue_active(&ctx
->inflight_wait
))
5812 wake_up(&ctx
->inflight_wait
);
5813 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
5814 req
->flags
&= ~REQ_F_INFLIGHT
;
5815 put_files_struct(req
->work
.identity
->files
);
5816 put_nsproxy(req
->work
.identity
->nsproxy
);
5817 req
->work
.flags
&= ~IO_WQ_WORK_FILES
;
5820 static void __io_clean_op(struct io_kiocb
*req
)
5822 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
5823 switch (req
->opcode
) {
5824 case IORING_OP_READV
:
5825 case IORING_OP_READ_FIXED
:
5826 case IORING_OP_READ
:
5827 kfree((void *)(unsigned long)req
->rw
.addr
);
5829 case IORING_OP_RECVMSG
:
5830 case IORING_OP_RECV
:
5831 kfree(req
->sr_msg
.kbuf
);
5834 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
5837 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
5838 switch (req
->opcode
) {
5839 case IORING_OP_READV
:
5840 case IORING_OP_READ_FIXED
:
5841 case IORING_OP_READ
:
5842 case IORING_OP_WRITEV
:
5843 case IORING_OP_WRITE_FIXED
:
5844 case IORING_OP_WRITE
: {
5845 struct io_async_rw
*io
= req
->async_data
;
5847 kfree(io
->free_iovec
);
5850 case IORING_OP_RECVMSG
:
5851 case IORING_OP_SENDMSG
: {
5852 struct io_async_msghdr
*io
= req
->async_data
;
5853 if (io
->iov
!= io
->fast_iov
)
5857 case IORING_OP_SPLICE
:
5859 io_put_file(req
, req
->splice
.file_in
,
5860 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
5862 case IORING_OP_OPENAT
:
5863 case IORING_OP_OPENAT2
:
5864 if (req
->open
.filename
)
5865 putname(req
->open
.filename
);
5868 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5871 if (req
->flags
& REQ_F_INFLIGHT
)
5872 io_req_drop_files(req
);
5875 static int io_issue_sqe(struct io_kiocb
*req
, bool force_nonblock
,
5876 struct io_comp_state
*cs
)
5878 struct io_ring_ctx
*ctx
= req
->ctx
;
5881 switch (req
->opcode
) {
5883 ret
= io_nop(req
, cs
);
5885 case IORING_OP_READV
:
5886 case IORING_OP_READ_FIXED
:
5887 case IORING_OP_READ
:
5888 ret
= io_read(req
, force_nonblock
, cs
);
5890 case IORING_OP_WRITEV
:
5891 case IORING_OP_WRITE_FIXED
:
5892 case IORING_OP_WRITE
:
5893 ret
= io_write(req
, force_nonblock
, cs
);
5895 case IORING_OP_FSYNC
:
5896 ret
= io_fsync(req
, force_nonblock
);
5898 case IORING_OP_POLL_ADD
:
5899 ret
= io_poll_add(req
);
5901 case IORING_OP_POLL_REMOVE
:
5902 ret
= io_poll_remove(req
);
5904 case IORING_OP_SYNC_FILE_RANGE
:
5905 ret
= io_sync_file_range(req
, force_nonblock
);
5907 case IORING_OP_SENDMSG
:
5908 ret
= io_sendmsg(req
, force_nonblock
, cs
);
5910 case IORING_OP_SEND
:
5911 ret
= io_send(req
, force_nonblock
, cs
);
5913 case IORING_OP_RECVMSG
:
5914 ret
= io_recvmsg(req
, force_nonblock
, cs
);
5916 case IORING_OP_RECV
:
5917 ret
= io_recv(req
, force_nonblock
, cs
);
5919 case IORING_OP_TIMEOUT
:
5920 ret
= io_timeout(req
);
5922 case IORING_OP_TIMEOUT_REMOVE
:
5923 ret
= io_timeout_remove(req
);
5925 case IORING_OP_ACCEPT
:
5926 ret
= io_accept(req
, force_nonblock
, cs
);
5928 case IORING_OP_CONNECT
:
5929 ret
= io_connect(req
, force_nonblock
, cs
);
5931 case IORING_OP_ASYNC_CANCEL
:
5932 ret
= io_async_cancel(req
);
5934 case IORING_OP_FALLOCATE
:
5935 ret
= io_fallocate(req
, force_nonblock
);
5937 case IORING_OP_OPENAT
:
5938 ret
= io_openat(req
, force_nonblock
);
5940 case IORING_OP_CLOSE
:
5941 ret
= io_close(req
, force_nonblock
, cs
);
5943 case IORING_OP_FILES_UPDATE
:
5944 ret
= io_files_update(req
, force_nonblock
, cs
);
5946 case IORING_OP_STATX
:
5947 ret
= io_statx(req
, force_nonblock
);
5949 case IORING_OP_FADVISE
:
5950 ret
= io_fadvise(req
, force_nonblock
);
5952 case IORING_OP_MADVISE
:
5953 ret
= io_madvise(req
, force_nonblock
);
5955 case IORING_OP_OPENAT2
:
5956 ret
= io_openat2(req
, force_nonblock
);
5958 case IORING_OP_EPOLL_CTL
:
5959 ret
= io_epoll_ctl(req
, force_nonblock
, cs
);
5961 case IORING_OP_SPLICE
:
5962 ret
= io_splice(req
, force_nonblock
);
5964 case IORING_OP_PROVIDE_BUFFERS
:
5965 ret
= io_provide_buffers(req
, force_nonblock
, cs
);
5967 case IORING_OP_REMOVE_BUFFERS
:
5968 ret
= io_remove_buffers(req
, force_nonblock
, cs
);
5971 ret
= io_tee(req
, force_nonblock
);
5981 /* If the op doesn't have a file, we're not polling for it */
5982 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
5983 const bool in_async
= io_wq_current_is_worker();
5985 /* workqueue context doesn't hold uring_lock, grab it now */
5987 mutex_lock(&ctx
->uring_lock
);
5989 io_iopoll_req_issued(req
);
5992 mutex_unlock(&ctx
->uring_lock
);
5998 static struct io_wq_work
*io_wq_submit_work(struct io_wq_work
*work
)
6000 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6001 struct io_kiocb
*timeout
;
6004 timeout
= io_prep_linked_timeout(req
);
6006 io_queue_linked_timeout(timeout
);
6008 /* if NO_CANCEL is set, we must still run the work */
6009 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
6010 IO_WQ_WORK_CANCEL
) {
6016 ret
= io_issue_sqe(req
, false, NULL
);
6018 * We can get EAGAIN for polled IO even though we're
6019 * forcing a sync submission from here, since we can't
6020 * wait for request slots on the block side.
6029 req_set_fail_links(req
);
6030 io_req_complete(req
, ret
);
6033 return io_steal_work(req
);
6036 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6039 struct fixed_file_table
*table
;
6041 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
6042 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
6045 static struct file
*io_file_get(struct io_submit_state
*state
,
6046 struct io_kiocb
*req
, int fd
, bool fixed
)
6048 struct io_ring_ctx
*ctx
= req
->ctx
;
6052 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6054 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6055 file
= io_file_from_index(ctx
, fd
);
6057 req
->fixed_file_refs
= &ctx
->file_data
->node
->refs
;
6058 percpu_ref_get(req
->fixed_file_refs
);
6061 trace_io_uring_file_get(ctx
, fd
);
6062 file
= __io_file_get(state
, fd
);
6068 static int io_req_set_file(struct io_submit_state
*state
, struct io_kiocb
*req
,
6073 fixed
= (req
->flags
& REQ_F_FIXED_FILE
) != 0;
6074 if (unlikely(!fixed
&& io_async_submit(req
->ctx
)))
6077 req
->file
= io_file_get(state
, req
, fd
, fixed
);
6078 if (req
->file
|| io_op_defs
[req
->opcode
].needs_file_no_error
)
6083 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6085 struct io_timeout_data
*data
= container_of(timer
,
6086 struct io_timeout_data
, timer
);
6087 struct io_kiocb
*req
= data
->req
;
6088 struct io_ring_ctx
*ctx
= req
->ctx
;
6089 struct io_kiocb
*prev
= NULL
;
6090 unsigned long flags
;
6092 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6095 * We don't expect the list to be empty, that will only happen if we
6096 * race with the completion of the linked work.
6098 if (!list_empty(&req
->link_list
)) {
6099 prev
= list_entry(req
->link_list
.prev
, struct io_kiocb
,
6101 if (refcount_inc_not_zero(&prev
->refs
))
6102 list_del_init(&req
->link_list
);
6107 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6110 req_set_fail_links(prev
);
6111 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6114 io_req_complete(req
, -ETIME
);
6116 return HRTIMER_NORESTART
;
6119 static void __io_queue_linked_timeout(struct io_kiocb
*req
)
6122 * If the list is now empty, then our linked request finished before
6123 * we got a chance to setup the timer
6125 if (!list_empty(&req
->link_list
)) {
6126 struct io_timeout_data
*data
= req
->async_data
;
6128 data
->timer
.function
= io_link_timeout_fn
;
6129 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6134 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6136 struct io_ring_ctx
*ctx
= req
->ctx
;
6138 spin_lock_irq(&ctx
->completion_lock
);
6139 __io_queue_linked_timeout(req
);
6140 spin_unlock_irq(&ctx
->completion_lock
);
6142 /* drop submission reference */
6146 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6148 struct io_kiocb
*nxt
;
6150 if (!(req
->flags
& REQ_F_LINK_HEAD
))
6152 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
6155 nxt
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
6157 if (!nxt
|| nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6160 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6161 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6165 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
)
6167 struct io_kiocb
*linked_timeout
;
6168 const struct cred
*old_creds
= NULL
;
6172 linked_timeout
= io_prep_linked_timeout(req
);
6174 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
6175 (req
->work
.flags
& IO_WQ_WORK_CREDS
) &&
6176 req
->work
.identity
->creds
!= current_cred()) {
6178 revert_creds(old_creds
);
6179 if (old_creds
== req
->work
.identity
->creds
)
6180 old_creds
= NULL
; /* restored original creds */
6182 old_creds
= override_creds(req
->work
.identity
->creds
);
6185 ret
= io_issue_sqe(req
, true, cs
);
6188 * We async punt it if the file wasn't marked NOWAIT, or if the file
6189 * doesn't support non-blocking read/write attempts
6191 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6192 if (!io_arm_poll_handler(req
)) {
6194 * Queued up for async execution, worker will release
6195 * submit reference when the iocb is actually submitted.
6197 io_queue_async_work(req
);
6201 io_queue_linked_timeout(linked_timeout
);
6202 } else if (likely(!ret
)) {
6203 /* drop submission reference */
6204 req
= io_put_req_find_next(req
);
6206 io_queue_linked_timeout(linked_timeout
);
6209 if (!(req
->flags
& REQ_F_FORCE_ASYNC
))
6211 io_queue_async_work(req
);
6214 /* un-prep timeout, so it'll be killed as any other linked */
6215 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6216 req_set_fail_links(req
);
6218 io_req_complete(req
, ret
);
6222 revert_creds(old_creds
);
6225 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6226 struct io_comp_state
*cs
)
6230 ret
= io_req_defer(req
, sqe
);
6232 if (ret
!= -EIOCBQUEUED
) {
6234 req_set_fail_links(req
);
6236 io_req_complete(req
, ret
);
6238 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6239 if (!req
->async_data
) {
6240 ret
= io_req_defer_prep(req
, sqe
);
6244 io_queue_async_work(req
);
6247 ret
= io_req_prep(req
, sqe
);
6251 __io_queue_sqe(req
, cs
);
6255 static inline void io_queue_link_head(struct io_kiocb
*req
,
6256 struct io_comp_state
*cs
)
6258 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6260 io_req_complete(req
, -ECANCELED
);
6262 io_queue_sqe(req
, NULL
, cs
);
6265 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6266 struct io_kiocb
**link
, struct io_comp_state
*cs
)
6268 struct io_ring_ctx
*ctx
= req
->ctx
;
6272 * If we already have a head request, queue this one for async
6273 * submittal once the head completes. If we don't have a head but
6274 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6275 * submitted sync once the chain is complete. If none of those
6276 * conditions are true (normal request), then just queue it.
6279 struct io_kiocb
*head
= *link
;
6282 * Taking sequential execution of a link, draining both sides
6283 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6284 * requests in the link. So, it drains the head and the
6285 * next after the link request. The last one is done via
6286 * drain_next flag to persist the effect across calls.
6288 if (req
->flags
& REQ_F_IO_DRAIN
) {
6289 head
->flags
|= REQ_F_IO_DRAIN
;
6290 ctx
->drain_next
= 1;
6292 ret
= io_req_defer_prep(req
, sqe
);
6293 if (unlikely(ret
)) {
6294 /* fail even hard links since we don't submit */
6295 head
->flags
|= REQ_F_FAIL_LINK
;
6298 trace_io_uring_link(ctx
, req
, head
);
6299 list_add_tail(&req
->link_list
, &head
->link_list
);
6301 /* last request of a link, enqueue the link */
6302 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6303 io_queue_link_head(head
, cs
);
6307 if (unlikely(ctx
->drain_next
)) {
6308 req
->flags
|= REQ_F_IO_DRAIN
;
6309 ctx
->drain_next
= 0;
6311 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6312 req
->flags
|= REQ_F_LINK_HEAD
;
6313 INIT_LIST_HEAD(&req
->link_list
);
6315 ret
= io_req_defer_prep(req
, sqe
);
6317 req
->flags
|= REQ_F_FAIL_LINK
;
6320 io_queue_sqe(req
, sqe
, cs
);
6328 * Batched submission is done, ensure local IO is flushed out.
6330 static void io_submit_state_end(struct io_submit_state
*state
)
6332 if (!list_empty(&state
->comp
.list
))
6333 io_submit_flush_completions(&state
->comp
);
6334 blk_finish_plug(&state
->plug
);
6335 io_state_file_put(state
);
6336 if (state
->free_reqs
)
6337 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
6341 * Start submission side cache.
6343 static void io_submit_state_start(struct io_submit_state
*state
,
6344 struct io_ring_ctx
*ctx
, unsigned int max_ios
)
6346 blk_start_plug(&state
->plug
);
6348 INIT_LIST_HEAD(&state
->comp
.list
);
6349 state
->comp
.ctx
= ctx
;
6350 state
->free_reqs
= 0;
6352 state
->ios_left
= max_ios
;
6355 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6357 struct io_rings
*rings
= ctx
->rings
;
6360 * Ensure any loads from the SQEs are done at this point,
6361 * since once we write the new head, the application could
6362 * write new data to them.
6364 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6368 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6369 * that is mapped by userspace. This means that care needs to be taken to
6370 * ensure that reads are stable, as we cannot rely on userspace always
6371 * being a good citizen. If members of the sqe are validated and then later
6372 * used, it's important that those reads are done through READ_ONCE() to
6373 * prevent a re-load down the line.
6375 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6377 u32
*sq_array
= ctx
->sq_array
;
6381 * The cached sq head (or cq tail) serves two purposes:
6383 * 1) allows us to batch the cost of updating the user visible
6385 * 2) allows the kernel side to track the head on its own, even
6386 * though the application is the one updating it.
6388 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
6389 if (likely(head
< ctx
->sq_entries
))
6390 return &ctx
->sq_sqes
[head
];
6392 /* drop invalid entries */
6393 ctx
->cached_sq_dropped
++;
6394 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6398 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
6400 ctx
->cached_sq_head
++;
6404 * Check SQE restrictions (opcode and flags).
6406 * Returns 'true' if SQE is allowed, 'false' otherwise.
6408 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6409 struct io_kiocb
*req
,
6410 unsigned int sqe_flags
)
6412 if (!ctx
->restricted
)
6415 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6418 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6419 ctx
->restrictions
.sqe_flags_required
)
6422 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6423 ctx
->restrictions
.sqe_flags_required
))
6429 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6430 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6431 IOSQE_BUFFER_SELECT)
6433 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6434 const struct io_uring_sqe
*sqe
,
6435 struct io_submit_state
*state
)
6437 unsigned int sqe_flags
;
6440 req
->opcode
= READ_ONCE(sqe
->opcode
);
6441 req
->user_data
= READ_ONCE(sqe
->user_data
);
6442 req
->async_data
= NULL
;
6446 /* one is dropped after submission, the other at completion */
6447 refcount_set(&req
->refs
, 2);
6448 req
->task
= current
;
6451 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6454 if (unlikely(io_sq_thread_acquire_mm(ctx
, req
)))
6457 sqe_flags
= READ_ONCE(sqe
->flags
);
6458 /* enforce forwards compatibility on users */
6459 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6462 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6465 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6466 !io_op_defs
[req
->opcode
].buffer_select
)
6469 id
= READ_ONCE(sqe
->personality
);
6471 struct io_identity
*iod
;
6473 iod
= idr_find(&ctx
->personality_idr
, id
);
6476 refcount_inc(&iod
->count
);
6478 __io_req_init_async(req
);
6479 get_cred(iod
->creds
);
6480 req
->work
.identity
= iod
;
6481 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
6484 /* same numerical values with corresponding REQ_F_*, safe to copy */
6485 req
->flags
|= sqe_flags
;
6487 if (!io_op_defs
[req
->opcode
].needs_file
)
6490 ret
= io_req_set_file(state
, req
, READ_ONCE(sqe
->fd
));
6495 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6497 struct io_submit_state state
;
6498 struct io_kiocb
*link
= NULL
;
6499 int i
, submitted
= 0;
6501 /* if we have a backlog and couldn't flush it all, return BUSY */
6502 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6503 if (!list_empty(&ctx
->cq_overflow_list
) &&
6504 !io_cqring_overflow_flush(ctx
, false, NULL
, NULL
))
6508 /* make sure SQ entry isn't read before tail */
6509 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6511 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6514 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6515 refcount_add(nr
, ¤t
->usage
);
6517 io_submit_state_start(&state
, ctx
, nr
);
6519 for (i
= 0; i
< nr
; i
++) {
6520 const struct io_uring_sqe
*sqe
;
6521 struct io_kiocb
*req
;
6524 sqe
= io_get_sqe(ctx
);
6525 if (unlikely(!sqe
)) {
6526 io_consume_sqe(ctx
);
6529 req
= io_alloc_req(ctx
, &state
);
6530 if (unlikely(!req
)) {
6532 submitted
= -EAGAIN
;
6535 io_consume_sqe(ctx
);
6536 /* will complete beyond this point, count as submitted */
6539 err
= io_init_req(ctx
, req
, sqe
, &state
);
6540 if (unlikely(err
)) {
6543 io_req_complete(req
, err
);
6547 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6548 true, io_async_submit(ctx
));
6549 err
= io_submit_sqe(req
, sqe
, &link
, &state
.comp
);
6554 if (unlikely(submitted
!= nr
)) {
6555 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6556 struct io_uring_task
*tctx
= current
->io_uring
;
6557 int unused
= nr
- ref_used
;
6559 percpu_ref_put_many(&ctx
->refs
, unused
);
6560 percpu_counter_sub(&tctx
->inflight
, unused
);
6561 put_task_struct_many(current
, unused
);
6564 io_queue_link_head(link
, &state
.comp
);
6565 io_submit_state_end(&state
);
6567 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6568 io_commit_sqring(ctx
);
6573 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6575 /* Tell userspace we may need a wakeup call */
6576 spin_lock_irq(&ctx
->completion_lock
);
6577 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6578 spin_unlock_irq(&ctx
->completion_lock
);
6581 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6583 spin_lock_irq(&ctx
->completion_lock
);
6584 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6585 spin_unlock_irq(&ctx
->completion_lock
);
6588 static int io_sq_wake_function(struct wait_queue_entry
*wqe
, unsigned mode
,
6589 int sync
, void *key
)
6591 struct io_ring_ctx
*ctx
= container_of(wqe
, struct io_ring_ctx
, sqo_wait_entry
);
6594 ret
= autoremove_wake_function(wqe
, mode
, sync
, key
);
6596 unsigned long flags
;
6598 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6599 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6600 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6611 static enum sq_ret
__io_sq_thread(struct io_ring_ctx
*ctx
,
6612 unsigned long start_jiffies
, bool cap_entries
)
6614 unsigned long timeout
= start_jiffies
+ ctx
->sq_thread_idle
;
6615 struct io_sq_data
*sqd
= ctx
->sq_data
;
6616 unsigned int to_submit
;
6620 if (!list_empty(&ctx
->iopoll_list
)) {
6621 unsigned nr_events
= 0;
6623 mutex_lock(&ctx
->uring_lock
);
6624 if (!list_empty(&ctx
->iopoll_list
) && !need_resched())
6625 io_do_iopoll(ctx
, &nr_events
, 0);
6626 mutex_unlock(&ctx
->uring_lock
);
6629 to_submit
= io_sqring_entries(ctx
);
6632 * If submit got -EBUSY, flag us as needing the application
6633 * to enter the kernel to reap and flush events.
6635 if (!to_submit
|| ret
== -EBUSY
|| need_resched()) {
6637 * Drop cur_mm before scheduling, we can't hold it for
6638 * long periods (or over schedule()). Do this before
6639 * adding ourselves to the waitqueue, as the unuse/drop
6642 io_sq_thread_drop_mm();
6645 * We're polling. If we're within the defined idle
6646 * period, then let us spin without work before going
6647 * to sleep. The exception is if we got EBUSY doing
6648 * more IO, we should wait for the application to
6649 * reap events and wake us up.
6651 if (!list_empty(&ctx
->iopoll_list
) || need_resched() ||
6652 (!time_after(jiffies
, timeout
) && ret
!= -EBUSY
&&
6653 !percpu_ref_is_dying(&ctx
->refs
)))
6656 prepare_to_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
,
6657 TASK_INTERRUPTIBLE
);
6660 * While doing polled IO, before going to sleep, we need
6661 * to check if there are new reqs added to iopoll_list,
6662 * it is because reqs may have been punted to io worker
6663 * and will be added to iopoll_list later, hence check
6664 * the iopoll_list again.
6666 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6667 !list_empty_careful(&ctx
->iopoll_list
)) {
6668 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
6672 to_submit
= io_sqring_entries(ctx
);
6673 if (!to_submit
|| ret
== -EBUSY
)
6677 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
6678 io_ring_clear_wakeup_flag(ctx
);
6680 /* if we're handling multiple rings, cap submit size for fairness */
6681 if (cap_entries
&& to_submit
> 8)
6684 mutex_lock(&ctx
->uring_lock
);
6685 if (likely(!percpu_ref_is_dying(&ctx
->refs
)))
6686 ret
= io_submit_sqes(ctx
, to_submit
);
6687 mutex_unlock(&ctx
->uring_lock
);
6689 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
6690 wake_up(&ctx
->sqo_sq_wait
);
6692 return SQT_DID_WORK
;
6695 static void io_sqd_init_new(struct io_sq_data
*sqd
)
6697 struct io_ring_ctx
*ctx
;
6699 while (!list_empty(&sqd
->ctx_new_list
)) {
6700 ctx
= list_first_entry(&sqd
->ctx_new_list
, struct io_ring_ctx
, sqd_list
);
6701 init_wait(&ctx
->sqo_wait_entry
);
6702 ctx
->sqo_wait_entry
.func
= io_sq_wake_function
;
6703 list_move_tail(&ctx
->sqd_list
, &sqd
->ctx_list
);
6704 complete(&ctx
->sq_thread_comp
);
6708 static int io_sq_thread(void *data
)
6710 struct cgroup_subsys_state
*cur_css
= NULL
;
6711 const struct cred
*old_cred
= NULL
;
6712 struct io_sq_data
*sqd
= data
;
6713 struct io_ring_ctx
*ctx
;
6714 unsigned long start_jiffies
;
6716 start_jiffies
= jiffies
;
6717 while (!kthread_should_stop()) {
6718 enum sq_ret ret
= 0;
6722 * Any changes to the sqd lists are synchronized through the
6723 * kthread parking. This synchronizes the thread vs users,
6724 * the users are synchronized on the sqd->ctx_lock.
6726 if (kthread_should_park())
6729 if (unlikely(!list_empty(&sqd
->ctx_new_list
)))
6730 io_sqd_init_new(sqd
);
6732 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
6734 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6735 if (current
->cred
!= ctx
->creds
) {
6737 revert_creds(old_cred
);
6738 old_cred
= override_creds(ctx
->creds
);
6740 io_sq_thread_associate_blkcg(ctx
, &cur_css
);
6742 current
->loginuid
= ctx
->loginuid
;
6743 current
->sessionid
= ctx
->sessionid
;
6746 ret
|= __io_sq_thread(ctx
, start_jiffies
, cap_entries
);
6748 io_sq_thread_drop_mm();
6751 if (ret
& SQT_SPIN
) {
6754 } else if (ret
== SQT_IDLE
) {
6755 if (kthread_should_park())
6757 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6758 io_ring_set_wakeup_flag(ctx
);
6760 start_jiffies
= jiffies
;
6761 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6762 io_ring_clear_wakeup_flag(ctx
);
6769 io_sq_thread_unassociate_blkcg();
6771 revert_creds(old_cred
);
6778 struct io_wait_queue
{
6779 struct wait_queue_entry wq
;
6780 struct io_ring_ctx
*ctx
;
6782 unsigned nr_timeouts
;
6785 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
6787 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6790 * Wake up if we have enough events, or if a timeout occurred since we
6791 * started waiting. For timeouts, we always want to return to userspace,
6792 * regardless of event count.
6794 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
6795 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6798 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6799 int wake_flags
, void *key
)
6801 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6804 /* use noflush == true, as we can't safely rely on locking context */
6805 if (!io_should_wake(iowq
, true))
6808 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6811 static int io_run_task_work_sig(void)
6813 if (io_run_task_work())
6815 if (!signal_pending(current
))
6817 if (current
->jobctl
& JOBCTL_TASK_WORK
) {
6818 spin_lock_irq(¤t
->sighand
->siglock
);
6819 current
->jobctl
&= ~JOBCTL_TASK_WORK
;
6820 recalc_sigpending();
6821 spin_unlock_irq(¤t
->sighand
->siglock
);
6828 * Wait until events become available, if we don't already have some. The
6829 * application must reap them itself, as they reside on the shared cq ring.
6831 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6832 const sigset_t __user
*sig
, size_t sigsz
)
6834 struct io_wait_queue iowq
= {
6837 .func
= io_wake_function
,
6838 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6841 .to_wait
= min_events
,
6843 struct io_rings
*rings
= ctx
->rings
;
6847 if (io_cqring_events(ctx
, false) >= min_events
)
6849 if (!io_run_task_work())
6854 #ifdef CONFIG_COMPAT
6855 if (in_compat_syscall())
6856 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6860 ret
= set_user_sigmask(sig
, sigsz
);
6866 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6867 trace_io_uring_cqring_wait(ctx
, min_events
);
6869 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
6870 TASK_INTERRUPTIBLE
);
6871 /* make sure we run task_work before checking for signals */
6872 ret
= io_run_task_work_sig();
6877 if (io_should_wake(&iowq
, false))
6881 finish_wait(&ctx
->wait
, &iowq
.wq
);
6883 restore_saved_sigmask_unless(ret
== -EINTR
);
6885 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
6888 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6890 #if defined(CONFIG_UNIX)
6891 if (ctx
->ring_sock
) {
6892 struct sock
*sock
= ctx
->ring_sock
->sk
;
6893 struct sk_buff
*skb
;
6895 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
6901 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6904 file
= io_file_from_index(ctx
, i
);
6911 static void io_file_ref_kill(struct percpu_ref
*ref
)
6913 struct fixed_file_data
*data
;
6915 data
= container_of(ref
, struct fixed_file_data
, refs
);
6916 complete(&data
->done
);
6919 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6921 struct fixed_file_data
*data
= ctx
->file_data
;
6922 struct fixed_file_ref_node
*ref_node
= NULL
;
6923 unsigned nr_tables
, i
;
6928 spin_lock(&data
->lock
);
6929 if (!list_empty(&data
->ref_list
))
6930 ref_node
= list_first_entry(&data
->ref_list
,
6931 struct fixed_file_ref_node
, node
);
6932 spin_unlock(&data
->lock
);
6934 percpu_ref_kill(&ref_node
->refs
);
6936 percpu_ref_kill(&data
->refs
);
6938 /* wait for all refs nodes to complete */
6939 flush_delayed_work(&ctx
->file_put_work
);
6940 wait_for_completion(&data
->done
);
6942 __io_sqe_files_unregister(ctx
);
6943 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
6944 for (i
= 0; i
< nr_tables
; i
++)
6945 kfree(data
->table
[i
].files
);
6947 percpu_ref_exit(&data
->refs
);
6949 ctx
->file_data
= NULL
;
6950 ctx
->nr_user_files
= 0;
6954 static void io_put_sq_data(struct io_sq_data
*sqd
)
6956 if (refcount_dec_and_test(&sqd
->refs
)) {
6958 * The park is a bit of a work-around, without it we get
6959 * warning spews on shutdown with SQPOLL set and affinity
6960 * set to a single CPU.
6963 kthread_park(sqd
->thread
);
6964 kthread_stop(sqd
->thread
);
6971 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
6973 struct io_ring_ctx
*ctx_attach
;
6974 struct io_sq_data
*sqd
;
6977 f
= fdget(p
->wq_fd
);
6979 return ERR_PTR(-ENXIO
);
6980 if (f
.file
->f_op
!= &io_uring_fops
) {
6982 return ERR_PTR(-EINVAL
);
6985 ctx_attach
= f
.file
->private_data
;
6986 sqd
= ctx_attach
->sq_data
;
6989 return ERR_PTR(-EINVAL
);
6992 refcount_inc(&sqd
->refs
);
6997 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
)
6999 struct io_sq_data
*sqd
;
7001 if (p
->flags
& IORING_SETUP_ATTACH_WQ
)
7002 return io_attach_sq_data(p
);
7004 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7006 return ERR_PTR(-ENOMEM
);
7008 refcount_set(&sqd
->refs
, 1);
7009 INIT_LIST_HEAD(&sqd
->ctx_list
);
7010 INIT_LIST_HEAD(&sqd
->ctx_new_list
);
7011 mutex_init(&sqd
->ctx_lock
);
7012 mutex_init(&sqd
->lock
);
7013 init_waitqueue_head(&sqd
->wait
);
7017 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7018 __releases(&sqd
->lock
)
7022 kthread_unpark(sqd
->thread
);
7023 mutex_unlock(&sqd
->lock
);
7026 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7027 __acquires(&sqd
->lock
)
7031 mutex_lock(&sqd
->lock
);
7032 kthread_park(sqd
->thread
);
7035 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
7037 struct io_sq_data
*sqd
= ctx
->sq_data
;
7042 * We may arrive here from the error branch in
7043 * io_sq_offload_create() where the kthread is created
7044 * without being waked up, thus wake it up now to make
7045 * sure the wait will complete.
7047 wake_up_process(sqd
->thread
);
7048 wait_for_completion(&ctx
->sq_thread_comp
);
7050 io_sq_thread_park(sqd
);
7053 mutex_lock(&sqd
->ctx_lock
);
7054 list_del(&ctx
->sqd_list
);
7055 mutex_unlock(&sqd
->ctx_lock
);
7058 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
7059 io_sq_thread_unpark(sqd
);
7062 io_put_sq_data(sqd
);
7063 ctx
->sq_data
= NULL
;
7067 static void io_finish_async(struct io_ring_ctx
*ctx
)
7069 io_sq_thread_stop(ctx
);
7072 io_wq_destroy(ctx
->io_wq
);
7077 #if defined(CONFIG_UNIX)
7079 * Ensure the UNIX gc is aware of our file set, so we are certain that
7080 * the io_uring can be safely unregistered on process exit, even if we have
7081 * loops in the file referencing.
7083 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7085 struct sock
*sk
= ctx
->ring_sock
->sk
;
7086 struct scm_fp_list
*fpl
;
7087 struct sk_buff
*skb
;
7090 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7094 skb
= alloc_skb(0, GFP_KERNEL
);
7103 fpl
->user
= get_uid(ctx
->user
);
7104 for (i
= 0; i
< nr
; i
++) {
7105 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7109 fpl
->fp
[nr_files
] = get_file(file
);
7110 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7115 fpl
->max
= SCM_MAX_FD
;
7116 fpl
->count
= nr_files
;
7117 UNIXCB(skb
).fp
= fpl
;
7118 skb
->destructor
= unix_destruct_scm
;
7119 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7120 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7122 for (i
= 0; i
< nr_files
; i
++)
7133 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7134 * causes regular reference counting to break down. We rely on the UNIX
7135 * garbage collection to take care of this problem for us.
7137 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7139 unsigned left
, total
;
7143 left
= ctx
->nr_user_files
;
7145 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7147 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7151 total
+= this_files
;
7157 while (total
< ctx
->nr_user_files
) {
7158 struct file
*file
= io_file_from_index(ctx
, total
);
7168 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7174 static int io_sqe_alloc_file_tables(struct fixed_file_data
*file_data
,
7175 unsigned nr_tables
, unsigned nr_files
)
7179 for (i
= 0; i
< nr_tables
; i
++) {
7180 struct fixed_file_table
*table
= &file_data
->table
[i
];
7181 unsigned this_files
;
7183 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7184 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
7188 nr_files
-= this_files
;
7194 for (i
= 0; i
< nr_tables
; i
++) {
7195 struct fixed_file_table
*table
= &file_data
->table
[i
];
7196 kfree(table
->files
);
7201 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
7203 #if defined(CONFIG_UNIX)
7204 struct sock
*sock
= ctx
->ring_sock
->sk
;
7205 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7206 struct sk_buff
*skb
;
7209 __skb_queue_head_init(&list
);
7212 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7213 * remove this entry and rearrange the file array.
7215 skb
= skb_dequeue(head
);
7217 struct scm_fp_list
*fp
;
7219 fp
= UNIXCB(skb
).fp
;
7220 for (i
= 0; i
< fp
->count
; i
++) {
7223 if (fp
->fp
[i
] != file
)
7226 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7227 left
= fp
->count
- 1 - i
;
7229 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7230 left
* sizeof(struct file
*));
7237 __skb_queue_tail(&list
, skb
);
7247 __skb_queue_tail(&list
, skb
);
7249 skb
= skb_dequeue(head
);
7252 if (skb_peek(&list
)) {
7253 spin_lock_irq(&head
->lock
);
7254 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7255 __skb_queue_tail(head
, skb
);
7256 spin_unlock_irq(&head
->lock
);
7263 struct io_file_put
{
7264 struct list_head list
;
7268 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
7270 struct fixed_file_data
*file_data
= ref_node
->file_data
;
7271 struct io_ring_ctx
*ctx
= file_data
->ctx
;
7272 struct io_file_put
*pfile
, *tmp
;
7274 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
7275 list_del(&pfile
->list
);
7276 io_ring_file_put(ctx
, pfile
->file
);
7280 spin_lock(&file_data
->lock
);
7281 list_del(&ref_node
->node
);
7282 spin_unlock(&file_data
->lock
);
7284 percpu_ref_exit(&ref_node
->refs
);
7286 percpu_ref_put(&file_data
->refs
);
7289 static void io_file_put_work(struct work_struct
*work
)
7291 struct io_ring_ctx
*ctx
;
7292 struct llist_node
*node
;
7294 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
7295 node
= llist_del_all(&ctx
->file_put_llist
);
7298 struct fixed_file_ref_node
*ref_node
;
7299 struct llist_node
*next
= node
->next
;
7301 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
7302 __io_file_put_work(ref_node
);
7307 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
7309 struct fixed_file_ref_node
*ref_node
;
7310 struct io_ring_ctx
*ctx
;
7314 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
7315 ctx
= ref_node
->file_data
->ctx
;
7317 if (percpu_ref_is_dying(&ctx
->file_data
->refs
))
7320 first_add
= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
7322 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
7324 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
7327 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
7328 struct io_ring_ctx
*ctx
)
7330 struct fixed_file_ref_node
*ref_node
;
7332 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7334 return ERR_PTR(-ENOMEM
);
7336 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
7339 return ERR_PTR(-ENOMEM
);
7341 INIT_LIST_HEAD(&ref_node
->node
);
7342 INIT_LIST_HEAD(&ref_node
->file_list
);
7343 ref_node
->file_data
= ctx
->file_data
;
7347 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
7349 percpu_ref_exit(&ref_node
->refs
);
7353 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7356 __s32 __user
*fds
= (__s32 __user
*) arg
;
7357 unsigned nr_tables
, i
;
7359 int fd
, ret
= -ENOMEM
;
7360 struct fixed_file_ref_node
*ref_node
;
7361 struct fixed_file_data
*file_data
;
7367 if (nr_args
> IORING_MAX_FIXED_FILES
)
7370 file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
7373 file_data
->ctx
= ctx
;
7374 init_completion(&file_data
->done
);
7375 INIT_LIST_HEAD(&file_data
->ref_list
);
7376 spin_lock_init(&file_data
->lock
);
7378 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7379 file_data
->table
= kcalloc(nr_tables
, sizeof(*file_data
->table
),
7381 if (!file_data
->table
)
7384 if (percpu_ref_init(&file_data
->refs
, io_file_ref_kill
,
7385 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
7388 if (io_sqe_alloc_file_tables(file_data
, nr_tables
, nr_args
))
7390 ctx
->file_data
= file_data
;
7392 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7393 struct fixed_file_table
*table
;
7396 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7400 /* allow sparse sets */
7410 * Don't allow io_uring instances to be registered. If UNIX
7411 * isn't enabled, then this causes a reference cycle and this
7412 * instance can never get freed. If UNIX is enabled we'll
7413 * handle it just fine, but there's still no point in allowing
7414 * a ring fd as it doesn't support regular read/write anyway.
7416 if (file
->f_op
== &io_uring_fops
) {
7420 table
= &file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7421 index
= i
& IORING_FILE_TABLE_MASK
;
7422 table
->files
[index
] = file
;
7425 ret
= io_sqe_files_scm(ctx
);
7427 io_sqe_files_unregister(ctx
);
7431 ref_node
= alloc_fixed_file_ref_node(ctx
);
7432 if (IS_ERR(ref_node
)) {
7433 io_sqe_files_unregister(ctx
);
7434 return PTR_ERR(ref_node
);
7437 file_data
->node
= ref_node
;
7438 spin_lock(&file_data
->lock
);
7439 list_add(&ref_node
->node
, &file_data
->ref_list
);
7440 spin_unlock(&file_data
->lock
);
7441 percpu_ref_get(&file_data
->refs
);
7444 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7445 file
= io_file_from_index(ctx
, i
);
7449 for (i
= 0; i
< nr_tables
; i
++)
7450 kfree(file_data
->table
[i
].files
);
7451 ctx
->nr_user_files
= 0;
7453 percpu_ref_exit(&file_data
->refs
);
7455 kfree(file_data
->table
);
7457 ctx
->file_data
= NULL
;
7461 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7464 #if defined(CONFIG_UNIX)
7465 struct sock
*sock
= ctx
->ring_sock
->sk
;
7466 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7467 struct sk_buff
*skb
;
7470 * See if we can merge this file into an existing skb SCM_RIGHTS
7471 * file set. If there's no room, fall back to allocating a new skb
7472 * and filling it in.
7474 spin_lock_irq(&head
->lock
);
7475 skb
= skb_peek(head
);
7477 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7479 if (fpl
->count
< SCM_MAX_FD
) {
7480 __skb_unlink(skb
, head
);
7481 spin_unlock_irq(&head
->lock
);
7482 fpl
->fp
[fpl
->count
] = get_file(file
);
7483 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7485 spin_lock_irq(&head
->lock
);
7486 __skb_queue_head(head
, skb
);
7491 spin_unlock_irq(&head
->lock
);
7498 return __io_sqe_files_scm(ctx
, 1, index
);
7504 static int io_queue_file_removal(struct fixed_file_data
*data
,
7507 struct io_file_put
*pfile
;
7508 struct fixed_file_ref_node
*ref_node
= data
->node
;
7510 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
7515 list_add(&pfile
->list
, &ref_node
->file_list
);
7520 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7521 struct io_uring_files_update
*up
,
7524 struct fixed_file_data
*data
= ctx
->file_data
;
7525 struct fixed_file_ref_node
*ref_node
;
7530 bool needs_switch
= false;
7532 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7534 if (done
> ctx
->nr_user_files
)
7537 ref_node
= alloc_fixed_file_ref_node(ctx
);
7538 if (IS_ERR(ref_node
))
7539 return PTR_ERR(ref_node
);
7542 fds
= u64_to_user_ptr(up
->fds
);
7544 struct fixed_file_table
*table
;
7548 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7552 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
7553 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7554 index
= i
& IORING_FILE_TABLE_MASK
;
7555 if (table
->files
[index
]) {
7556 file
= table
->files
[index
];
7557 err
= io_queue_file_removal(data
, file
);
7560 table
->files
[index
] = NULL
;
7561 needs_switch
= true;
7570 * Don't allow io_uring instances to be registered. If
7571 * UNIX isn't enabled, then this causes a reference
7572 * cycle and this instance can never get freed. If UNIX
7573 * is enabled we'll handle it just fine, but there's
7574 * still no point in allowing a ring fd as it doesn't
7575 * support regular read/write anyway.
7577 if (file
->f_op
== &io_uring_fops
) {
7582 table
->files
[index
] = file
;
7583 err
= io_sqe_file_register(ctx
, file
, i
);
7585 table
->files
[index
] = NULL
;
7596 percpu_ref_kill(&data
->node
->refs
);
7597 spin_lock(&data
->lock
);
7598 list_add(&ref_node
->node
, &data
->ref_list
);
7599 data
->node
= ref_node
;
7600 spin_unlock(&data
->lock
);
7601 percpu_ref_get(&ctx
->file_data
->refs
);
7603 destroy_fixed_file_ref_node(ref_node
);
7605 return done
? done
: err
;
7608 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7611 struct io_uring_files_update up
;
7613 if (!ctx
->file_data
)
7617 if (copy_from_user(&up
, arg
, sizeof(up
)))
7622 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7625 static void io_free_work(struct io_wq_work
*work
)
7627 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7629 /* Consider that io_steal_work() relies on this ref */
7633 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
7634 struct io_uring_params
*p
)
7636 struct io_wq_data data
;
7638 struct io_ring_ctx
*ctx_attach
;
7639 unsigned int concurrency
;
7642 data
.user
= ctx
->user
;
7643 data
.free_work
= io_free_work
;
7644 data
.do_work
= io_wq_submit_work
;
7646 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
7647 /* Do QD, or 4 * CPUS, whatever is smallest */
7648 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7650 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
7651 if (IS_ERR(ctx
->io_wq
)) {
7652 ret
= PTR_ERR(ctx
->io_wq
);
7658 f
= fdget(p
->wq_fd
);
7662 if (f
.file
->f_op
!= &io_uring_fops
) {
7667 ctx_attach
= f
.file
->private_data
;
7668 /* @io_wq is protected by holding the fd */
7669 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
7674 ctx
->io_wq
= ctx_attach
->io_wq
;
7680 static int io_uring_alloc_task_context(struct task_struct
*task
)
7682 struct io_uring_task
*tctx
;
7685 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
7686 if (unlikely(!tctx
))
7689 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
7690 if (unlikely(ret
)) {
7696 init_waitqueue_head(&tctx
->wait
);
7699 io_init_identity(&tctx
->__identity
);
7700 tctx
->identity
= &tctx
->__identity
;
7701 task
->io_uring
= tctx
;
7705 void __io_uring_free(struct task_struct
*tsk
)
7707 struct io_uring_task
*tctx
= tsk
->io_uring
;
7709 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
7710 WARN_ON_ONCE(refcount_read(&tctx
->identity
->count
) != 1);
7711 if (tctx
->identity
!= &tctx
->__identity
)
7712 kfree(tctx
->identity
);
7713 percpu_counter_destroy(&tctx
->inflight
);
7715 tsk
->io_uring
= NULL
;
7718 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
7719 struct io_uring_params
*p
)
7723 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7724 struct io_sq_data
*sqd
;
7727 if (!capable(CAP_SYS_ADMIN
))
7730 sqd
= io_get_sq_data(p
);
7737 io_sq_thread_park(sqd
);
7738 mutex_lock(&sqd
->ctx_lock
);
7739 list_add(&ctx
->sqd_list
, &sqd
->ctx_new_list
);
7740 mutex_unlock(&sqd
->ctx_lock
);
7741 io_sq_thread_unpark(sqd
);
7743 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
7744 if (!ctx
->sq_thread_idle
)
7745 ctx
->sq_thread_idle
= HZ
;
7750 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7751 int cpu
= p
->sq_thread_cpu
;
7754 if (cpu
>= nr_cpu_ids
)
7756 if (!cpu_online(cpu
))
7759 sqd
->thread
= kthread_create_on_cpu(io_sq_thread
, sqd
,
7760 cpu
, "io_uring-sq");
7762 sqd
->thread
= kthread_create(io_sq_thread
, sqd
,
7765 if (IS_ERR(sqd
->thread
)) {
7766 ret
= PTR_ERR(sqd
->thread
);
7770 ret
= io_uring_alloc_task_context(sqd
->thread
);
7773 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7774 /* Can't have SQ_AFF without SQPOLL */
7780 ret
= io_init_wq_offload(ctx
, p
);
7786 io_finish_async(ctx
);
7790 static void io_sq_offload_start(struct io_ring_ctx
*ctx
)
7792 struct io_sq_data
*sqd
= ctx
->sq_data
;
7794 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && sqd
->thread
)
7795 wake_up_process(sqd
->thread
);
7798 static inline void __io_unaccount_mem(struct user_struct
*user
,
7799 unsigned long nr_pages
)
7801 atomic_long_sub(nr_pages
, &user
->locked_vm
);
7804 static inline int __io_account_mem(struct user_struct
*user
,
7805 unsigned long nr_pages
)
7807 unsigned long page_limit
, cur_pages
, new_pages
;
7809 /* Don't allow more pages than we can safely lock */
7810 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
7813 cur_pages
= atomic_long_read(&user
->locked_vm
);
7814 new_pages
= cur_pages
+ nr_pages
;
7815 if (new_pages
> page_limit
)
7817 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
7818 new_pages
) != cur_pages
);
7823 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7824 enum io_mem_account acct
)
7827 __io_unaccount_mem(ctx
->user
, nr_pages
);
7829 if (ctx
->mm_account
) {
7830 if (acct
== ACCT_LOCKED
)
7831 ctx
->mm_account
->locked_vm
-= nr_pages
;
7832 else if (acct
== ACCT_PINNED
)
7833 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
7837 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7838 enum io_mem_account acct
)
7842 if (ctx
->limit_mem
) {
7843 ret
= __io_account_mem(ctx
->user
, nr_pages
);
7848 if (ctx
->mm_account
) {
7849 if (acct
== ACCT_LOCKED
)
7850 ctx
->mm_account
->locked_vm
+= nr_pages
;
7851 else if (acct
== ACCT_PINNED
)
7852 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
7858 static void io_mem_free(void *ptr
)
7865 page
= virt_to_head_page(ptr
);
7866 if (put_page_testzero(page
))
7867 free_compound_page(page
);
7870 static void *io_mem_alloc(size_t size
)
7872 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
7875 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
7878 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
7881 struct io_rings
*rings
;
7882 size_t off
, sq_array_size
;
7884 off
= struct_size(rings
, cqes
, cq_entries
);
7885 if (off
== SIZE_MAX
)
7889 off
= ALIGN(off
, SMP_CACHE_BYTES
);
7897 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
7898 if (sq_array_size
== SIZE_MAX
)
7901 if (check_add_overflow(off
, sq_array_size
, &off
))
7907 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
7911 pages
= (size_t)1 << get_order(
7912 rings_size(sq_entries
, cq_entries
, NULL
));
7913 pages
+= (size_t)1 << get_order(
7914 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
7919 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
7923 if (!ctx
->user_bufs
)
7926 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7927 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7929 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
7930 unpin_user_page(imu
->bvec
[j
].bv_page
);
7932 if (imu
->acct_pages
)
7933 io_unaccount_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
7938 kfree(ctx
->user_bufs
);
7939 ctx
->user_bufs
= NULL
;
7940 ctx
->nr_user_bufs
= 0;
7944 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
7945 void __user
*arg
, unsigned index
)
7947 struct iovec __user
*src
;
7949 #ifdef CONFIG_COMPAT
7951 struct compat_iovec __user
*ciovs
;
7952 struct compat_iovec ciov
;
7954 ciovs
= (struct compat_iovec __user
*) arg
;
7955 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
7958 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
7959 dst
->iov_len
= ciov
.iov_len
;
7963 src
= (struct iovec __user
*) arg
;
7964 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
7970 * Not super efficient, but this is just a registration time. And we do cache
7971 * the last compound head, so generally we'll only do a full search if we don't
7974 * We check if the given compound head page has already been accounted, to
7975 * avoid double accounting it. This allows us to account the full size of the
7976 * page, not just the constituent pages of a huge page.
7978 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
7979 int nr_pages
, struct page
*hpage
)
7983 /* check current page array */
7984 for (i
= 0; i
< nr_pages
; i
++) {
7985 if (!PageCompound(pages
[i
]))
7987 if (compound_head(pages
[i
]) == hpage
)
7991 /* check previously registered pages */
7992 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7993 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7995 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
7996 if (!PageCompound(imu
->bvec
[j
].bv_page
))
7998 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8006 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8007 int nr_pages
, struct io_mapped_ubuf
*imu
,
8008 struct page
**last_hpage
)
8012 for (i
= 0; i
< nr_pages
; i
++) {
8013 if (!PageCompound(pages
[i
])) {
8018 hpage
= compound_head(pages
[i
]);
8019 if (hpage
== *last_hpage
)
8021 *last_hpage
= hpage
;
8022 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8024 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8028 if (!imu
->acct_pages
)
8031 ret
= io_account_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8033 imu
->acct_pages
= 0;
8037 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8040 struct vm_area_struct
**vmas
= NULL
;
8041 struct page
**pages
= NULL
;
8042 struct page
*last_hpage
= NULL
;
8043 int i
, j
, got_pages
= 0;
8048 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8051 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
8053 if (!ctx
->user_bufs
)
8056 for (i
= 0; i
< nr_args
; i
++) {
8057 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8058 unsigned long off
, start
, end
, ubuf
;
8063 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8068 * Don't impose further limits on the size and buffer
8069 * constraints here, we'll -EINVAL later when IO is
8070 * submitted if they are wrong.
8073 if (!iov
.iov_base
|| !iov
.iov_len
)
8076 /* arbitrary limit, but we need something */
8077 if (iov
.iov_len
> SZ_1G
)
8080 ubuf
= (unsigned long) iov
.iov_base
;
8081 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8082 start
= ubuf
>> PAGE_SHIFT
;
8083 nr_pages
= end
- start
;
8086 if (!pages
|| nr_pages
> got_pages
) {
8089 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
8091 vmas
= kvmalloc_array(nr_pages
,
8092 sizeof(struct vm_area_struct
*),
8094 if (!pages
|| !vmas
) {
8098 got_pages
= nr_pages
;
8101 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8108 mmap_read_lock(current
->mm
);
8109 pret
= pin_user_pages(ubuf
, nr_pages
,
8110 FOLL_WRITE
| FOLL_LONGTERM
,
8112 if (pret
== nr_pages
) {
8113 /* don't support file backed memory */
8114 for (j
= 0; j
< nr_pages
; j
++) {
8115 struct vm_area_struct
*vma
= vmas
[j
];
8118 !is_file_hugepages(vma
->vm_file
)) {
8124 ret
= pret
< 0 ? pret
: -EFAULT
;
8126 mmap_read_unlock(current
->mm
);
8129 * if we did partial map, or found file backed vmas,
8130 * release any pages we did get
8133 unpin_user_pages(pages
, pret
);
8138 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, &last_hpage
);
8140 unpin_user_pages(pages
, pret
);
8145 off
= ubuf
& ~PAGE_MASK
;
8147 for (j
= 0; j
< nr_pages
; j
++) {
8150 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8151 imu
->bvec
[j
].bv_page
= pages
[j
];
8152 imu
->bvec
[j
].bv_len
= vec_len
;
8153 imu
->bvec
[j
].bv_offset
= off
;
8157 /* store original address for later verification */
8159 imu
->len
= iov
.iov_len
;
8160 imu
->nr_bvecs
= nr_pages
;
8162 ctx
->nr_user_bufs
++;
8170 io_sqe_buffer_unregister(ctx
);
8174 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8176 __s32 __user
*fds
= arg
;
8182 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8185 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8186 if (IS_ERR(ctx
->cq_ev_fd
)) {
8187 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8188 ctx
->cq_ev_fd
= NULL
;
8195 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8197 if (ctx
->cq_ev_fd
) {
8198 eventfd_ctx_put(ctx
->cq_ev_fd
);
8199 ctx
->cq_ev_fd
= NULL
;
8206 static int __io_destroy_buffers(int id
, void *p
, void *data
)
8208 struct io_ring_ctx
*ctx
= data
;
8209 struct io_buffer
*buf
= p
;
8211 __io_remove_buffers(ctx
, buf
, id
, -1U);
8215 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8217 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
8218 idr_destroy(&ctx
->io_buffer_idr
);
8221 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8223 io_finish_async(ctx
);
8224 io_sqe_buffer_unregister(ctx
);
8226 if (ctx
->sqo_task
) {
8227 put_task_struct(ctx
->sqo_task
);
8228 ctx
->sqo_task
= NULL
;
8229 mmdrop(ctx
->mm_account
);
8230 ctx
->mm_account
= NULL
;
8233 #ifdef CONFIG_BLK_CGROUP
8234 if (ctx
->sqo_blkcg_css
)
8235 css_put(ctx
->sqo_blkcg_css
);
8238 io_sqe_files_unregister(ctx
);
8239 io_eventfd_unregister(ctx
);
8240 io_destroy_buffers(ctx
);
8241 idr_destroy(&ctx
->personality_idr
);
8243 #if defined(CONFIG_UNIX)
8244 if (ctx
->ring_sock
) {
8245 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8246 sock_release(ctx
->ring_sock
);
8250 io_mem_free(ctx
->rings
);
8251 io_mem_free(ctx
->sq_sqes
);
8253 percpu_ref_exit(&ctx
->refs
);
8254 free_uid(ctx
->user
);
8255 put_cred(ctx
->creds
);
8256 kfree(ctx
->cancel_hash
);
8257 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
8261 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8263 struct io_ring_ctx
*ctx
= file
->private_data
;
8266 poll_wait(file
, &ctx
->cq_wait
, wait
);
8268 * synchronizes with barrier from wq_has_sleeper call in
8272 if (!io_sqring_full(ctx
))
8273 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8274 if (io_cqring_events(ctx
, false))
8275 mask
|= EPOLLIN
| EPOLLRDNORM
;
8280 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8282 struct io_ring_ctx
*ctx
= file
->private_data
;
8284 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8287 static int io_remove_personalities(int id
, void *p
, void *data
)
8289 struct io_ring_ctx
*ctx
= data
;
8290 struct io_identity
*iod
;
8292 iod
= idr_remove(&ctx
->personality_idr
, id
);
8294 put_cred(iod
->creds
);
8295 if (refcount_dec_and_test(&iod
->count
))
8301 static void io_ring_exit_work(struct work_struct
*work
)
8303 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
8307 * If we're doing polled IO and end up having requests being
8308 * submitted async (out-of-line), then completions can come in while
8309 * we're waiting for refs to drop. We need to reap these manually,
8310 * as nobody else will be looking for them.
8314 io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8315 io_iopoll_try_reap_events(ctx
);
8316 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8317 io_ring_ctx_free(ctx
);
8320 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8322 mutex_lock(&ctx
->uring_lock
);
8323 percpu_ref_kill(&ctx
->refs
);
8324 mutex_unlock(&ctx
->uring_lock
);
8326 io_kill_timeouts(ctx
, NULL
);
8327 io_poll_remove_all(ctx
, NULL
);
8330 io_wq_cancel_all(ctx
->io_wq
);
8332 /* if we failed setting up the ctx, we might not have any rings */
8334 io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8335 io_iopoll_try_reap_events(ctx
);
8336 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
8339 * Do this upfront, so we won't have a grace period where the ring
8340 * is closed but resources aren't reaped yet. This can cause
8341 * spurious failure in setting up a new ring.
8343 io_unaccount_mem(ctx
, ring_pages(ctx
->sq_entries
, ctx
->cq_entries
),
8346 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8348 * Use system_unbound_wq to avoid spawning tons of event kworkers
8349 * if we're exiting a ton of rings at the same time. It just adds
8350 * noise and overhead, there's no discernable change in runtime
8351 * over using system_wq.
8353 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8356 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8358 struct io_ring_ctx
*ctx
= file
->private_data
;
8360 file
->private_data
= NULL
;
8361 io_ring_ctx_wait_and_kill(ctx
);
8365 static bool io_wq_files_match(struct io_wq_work
*work
, void *data
)
8367 struct files_struct
*files
= data
;
8369 return !files
|| ((work
->flags
& IO_WQ_WORK_FILES
) &&
8370 work
->identity
->files
== files
);
8374 * Returns true if 'preq' is the link parent of 'req'
8376 static bool io_match_link(struct io_kiocb
*preq
, struct io_kiocb
*req
)
8378 struct io_kiocb
*link
;
8380 if (!(preq
->flags
& REQ_F_LINK_HEAD
))
8383 list_for_each_entry(link
, &preq
->link_list
, link_list
) {
8391 static bool io_match_link_files(struct io_kiocb
*req
,
8392 struct files_struct
*files
)
8394 struct io_kiocb
*link
;
8396 if (io_match_files(req
, files
))
8398 if (req
->flags
& REQ_F_LINK_HEAD
) {
8399 list_for_each_entry(link
, &req
->link_list
, link_list
) {
8400 if (io_match_files(link
, files
))
8408 * We're looking to cancel 'req' because it's holding on to our files, but
8409 * 'req' could be a link to another request. See if it is, and cancel that
8410 * parent request if so.
8412 static bool io_poll_remove_link(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
)
8414 struct hlist_node
*tmp
;
8415 struct io_kiocb
*preq
;
8419 spin_lock_irq(&ctx
->completion_lock
);
8420 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
8421 struct hlist_head
*list
;
8423 list
= &ctx
->cancel_hash
[i
];
8424 hlist_for_each_entry_safe(preq
, tmp
, list
, hash_node
) {
8425 found
= io_match_link(preq
, req
);
8427 io_poll_remove_one(preq
);
8432 spin_unlock_irq(&ctx
->completion_lock
);
8436 static bool io_timeout_remove_link(struct io_ring_ctx
*ctx
,
8437 struct io_kiocb
*req
)
8439 struct io_kiocb
*preq
;
8442 spin_lock_irq(&ctx
->completion_lock
);
8443 list_for_each_entry(preq
, &ctx
->timeout_list
, timeout
.list
) {
8444 found
= io_match_link(preq
, req
);
8446 __io_timeout_cancel(preq
);
8450 spin_unlock_irq(&ctx
->completion_lock
);
8454 static bool io_cancel_link_cb(struct io_wq_work
*work
, void *data
)
8456 return io_match_link(container_of(work
, struct io_kiocb
, work
), data
);
8459 static void io_attempt_cancel(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
)
8461 enum io_wq_cancel cret
;
8463 /* cancel this particular work, if it's running */
8464 cret
= io_wq_cancel_work(ctx
->io_wq
, &req
->work
);
8465 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8468 /* find links that hold this pending, cancel those */
8469 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_link_cb
, req
, true);
8470 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8473 /* if we have a poll link holding this pending, cancel that */
8474 if (io_poll_remove_link(ctx
, req
))
8477 /* final option, timeout link is holding this req pending */
8478 io_timeout_remove_link(ctx
, req
);
8481 static void io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8482 struct files_struct
*files
)
8484 struct io_defer_entry
*de
= NULL
;
8487 spin_lock_irq(&ctx
->completion_lock
);
8488 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8489 if (io_match_link_files(de
->req
, files
)) {
8490 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8494 spin_unlock_irq(&ctx
->completion_lock
);
8496 while (!list_empty(&list
)) {
8497 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8498 list_del_init(&de
->list
);
8499 req_set_fail_links(de
->req
);
8500 io_put_req(de
->req
);
8501 io_req_complete(de
->req
, -ECANCELED
);
8507 * Returns true if we found and killed one or more files pinning requests
8509 static bool io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8510 struct files_struct
*files
)
8512 if (list_empty_careful(&ctx
->inflight_list
))
8515 io_cancel_defer_files(ctx
, files
);
8516 /* cancel all at once, should be faster than doing it one by one*/
8517 io_wq_cancel_cb(ctx
->io_wq
, io_wq_files_match
, files
, true);
8519 while (!list_empty_careful(&ctx
->inflight_list
)) {
8520 struct io_kiocb
*cancel_req
= NULL
, *req
;
8523 spin_lock_irq(&ctx
->inflight_lock
);
8524 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
8525 if (files
&& (req
->work
.flags
& IO_WQ_WORK_FILES
) &&
8526 req
->work
.identity
->files
!= files
)
8528 /* req is being completed, ignore */
8529 if (!refcount_inc_not_zero(&req
->refs
))
8535 prepare_to_wait(&ctx
->inflight_wait
, &wait
,
8536 TASK_UNINTERRUPTIBLE
);
8537 spin_unlock_irq(&ctx
->inflight_lock
);
8539 /* We need to keep going until we don't find a matching req */
8542 /* cancel this request, or head link requests */
8543 io_attempt_cancel(ctx
, cancel_req
);
8544 io_put_req(cancel_req
);
8545 /* cancellations _may_ trigger task work */
8548 finish_wait(&ctx
->inflight_wait
, &wait
);
8554 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8556 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8557 struct task_struct
*task
= data
;
8559 return io_task_match(req
, task
);
8562 static bool __io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8563 struct task_struct
*task
,
8564 struct files_struct
*files
)
8568 ret
= io_uring_cancel_files(ctx
, files
);
8570 enum io_wq_cancel cret
;
8572 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, task
, true);
8573 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8576 /* SQPOLL thread does its own polling */
8577 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8578 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8579 io_iopoll_try_reap_events(ctx
);
8584 ret
|= io_poll_remove_all(ctx
, task
);
8585 ret
|= io_kill_timeouts(ctx
, task
);
8592 * We need to iteratively cancel requests, in case a request has dependent
8593 * hard links. These persist even for failure of cancelations, hence keep
8594 * looping until none are found.
8596 static void io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8597 struct files_struct
*files
)
8599 struct task_struct
*task
= current
;
8601 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
)
8602 task
= ctx
->sq_data
->thread
;
8604 io_cqring_overflow_flush(ctx
, true, task
, files
);
8606 while (__io_uring_cancel_task_requests(ctx
, task
, files
)) {
8613 * Note that this task has used io_uring. We use it for cancelation purposes.
8615 static int io_uring_add_task_file(struct file
*file
)
8617 struct io_uring_task
*tctx
= current
->io_uring
;
8619 if (unlikely(!tctx
)) {
8622 ret
= io_uring_alloc_task_context(current
);
8625 tctx
= current
->io_uring
;
8627 if (tctx
->last
!= file
) {
8628 void *old
= xa_load(&tctx
->xa
, (unsigned long)file
);
8632 xa_store(&tctx
->xa
, (unsigned long)file
, file
, GFP_KERNEL
);
8641 * Remove this io_uring_file -> task mapping.
8643 static void io_uring_del_task_file(struct file
*file
)
8645 struct io_uring_task
*tctx
= current
->io_uring
;
8647 if (tctx
->last
== file
)
8649 file
= xa_erase(&tctx
->xa
, (unsigned long)file
);
8655 * Drop task note for this file if we're the only ones that hold it after
8658 static void io_uring_attempt_task_drop(struct file
*file
)
8660 if (!current
->io_uring
)
8663 * fput() is pending, will be 2 if the only other ref is our potential
8664 * task file note. If the task is exiting, drop regardless of count.
8666 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
) ||
8667 atomic_long_read(&file
->f_count
) == 2)
8668 io_uring_del_task_file(file
);
8671 void __io_uring_files_cancel(struct files_struct
*files
)
8673 struct io_uring_task
*tctx
= current
->io_uring
;
8675 unsigned long index
;
8677 /* make sure overflow events are dropped */
8678 tctx
->in_idle
= true;
8680 xa_for_each(&tctx
->xa
, index
, file
) {
8681 struct io_ring_ctx
*ctx
= file
->private_data
;
8683 io_uring_cancel_task_requests(ctx
, files
);
8685 io_uring_del_task_file(file
);
8690 * Find any io_uring fd that this task has registered or done IO on, and cancel
8693 void __io_uring_task_cancel(void)
8695 struct io_uring_task
*tctx
= current
->io_uring
;
8699 /* make sure overflow events are dropped */
8700 tctx
->in_idle
= true;
8703 /* read completions before cancelations */
8704 inflight
= percpu_counter_sum(&tctx
->inflight
);
8707 __io_uring_files_cancel(NULL
);
8709 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
8712 * If we've seen completions, retry. This avoids a race where
8713 * a completion comes in before we did prepare_to_wait().
8715 if (inflight
!= percpu_counter_sum(&tctx
->inflight
))
8720 finish_wait(&tctx
->wait
, &wait
);
8721 tctx
->in_idle
= false;
8724 static int io_uring_flush(struct file
*file
, void *data
)
8726 io_uring_attempt_task_drop(file
);
8730 static void *io_uring_validate_mmap_request(struct file
*file
,
8731 loff_t pgoff
, size_t sz
)
8733 struct io_ring_ctx
*ctx
= file
->private_data
;
8734 loff_t offset
= pgoff
<< PAGE_SHIFT
;
8739 case IORING_OFF_SQ_RING
:
8740 case IORING_OFF_CQ_RING
:
8743 case IORING_OFF_SQES
:
8747 return ERR_PTR(-EINVAL
);
8750 page
= virt_to_head_page(ptr
);
8751 if (sz
> page_size(page
))
8752 return ERR_PTR(-EINVAL
);
8759 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
8761 size_t sz
= vma
->vm_end
- vma
->vm_start
;
8765 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
8767 return PTR_ERR(ptr
);
8769 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
8770 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
8773 #else /* !CONFIG_MMU */
8775 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
8777 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
8780 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
8782 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
8785 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
8786 unsigned long addr
, unsigned long len
,
8787 unsigned long pgoff
, unsigned long flags
)
8791 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
8793 return PTR_ERR(ptr
);
8795 return (unsigned long) ptr
;
8798 #endif /* !CONFIG_MMU */
8800 static void io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
8805 if (!io_sqring_full(ctx
))
8808 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
8810 if (!io_sqring_full(ctx
))
8814 } while (!signal_pending(current
));
8816 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
8819 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
8820 u32
, min_complete
, u32
, flags
, const sigset_t __user
*, sig
,
8823 struct io_ring_ctx
*ctx
;
8830 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
8831 IORING_ENTER_SQ_WAIT
))
8839 if (f
.file
->f_op
!= &io_uring_fops
)
8843 ctx
= f
.file
->private_data
;
8844 if (!percpu_ref_tryget(&ctx
->refs
))
8848 if (ctx
->flags
& IORING_SETUP_R_DISABLED
)
8852 * For SQ polling, the thread will do all submissions and completions.
8853 * Just return the requested submit count, and wake the thread if
8857 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8858 if (!list_empty_careful(&ctx
->cq_overflow_list
))
8859 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
8860 if (flags
& IORING_ENTER_SQ_WAKEUP
)
8861 wake_up(&ctx
->sq_data
->wait
);
8862 if (flags
& IORING_ENTER_SQ_WAIT
)
8863 io_sqpoll_wait_sq(ctx
);
8864 submitted
= to_submit
;
8865 } else if (to_submit
) {
8866 ret
= io_uring_add_task_file(f
.file
);
8869 mutex_lock(&ctx
->uring_lock
);
8870 submitted
= io_submit_sqes(ctx
, to_submit
);
8871 mutex_unlock(&ctx
->uring_lock
);
8873 if (submitted
!= to_submit
)
8876 if (flags
& IORING_ENTER_GETEVENTS
) {
8877 min_complete
= min(min_complete
, ctx
->cq_entries
);
8880 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
8881 * space applications don't need to do io completion events
8882 * polling again, they can rely on io_sq_thread to do polling
8883 * work, which can reduce cpu usage and uring_lock contention.
8885 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
8886 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8887 ret
= io_iopoll_check(ctx
, min_complete
);
8889 ret
= io_cqring_wait(ctx
, min_complete
, sig
, sigsz
);
8894 percpu_ref_put(&ctx
->refs
);
8897 return submitted
? submitted
: ret
;
8900 #ifdef CONFIG_PROC_FS
8901 static int io_uring_show_cred(int id
, void *p
, void *data
)
8903 const struct cred
*cred
= p
;
8904 struct seq_file
*m
= data
;
8905 struct user_namespace
*uns
= seq_user_ns(m
);
8906 struct group_info
*gi
;
8911 seq_printf(m
, "%5d\n", id
);
8912 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
8913 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
8914 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
8915 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
8916 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
8917 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
8918 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
8919 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
8920 seq_puts(m
, "\n\tGroups:\t");
8921 gi
= cred
->group_info
;
8922 for (g
= 0; g
< gi
->ngroups
; g
++) {
8923 seq_put_decimal_ull(m
, g
? " " : "",
8924 from_kgid_munged(uns
, gi
->gid
[g
]));
8926 seq_puts(m
, "\n\tCapEff:\t");
8927 cap
= cred
->cap_effective
;
8928 CAP_FOR_EACH_U32(__capi
)
8929 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
8934 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
8936 struct io_sq_data
*sq
= NULL
;
8941 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
8942 * since fdinfo case grabs it in the opposite direction of normal use
8943 * cases. If we fail to get the lock, we just don't iterate any
8944 * structures that could be going away outside the io_uring mutex.
8946 has_lock
= mutex_trylock(&ctx
->uring_lock
);
8948 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
8951 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
8952 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
8953 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
8954 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
8955 struct fixed_file_table
*table
;
8958 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
8959 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
8961 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
8963 seq_printf(m
, "%5u: <none>\n", i
);
8965 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
8966 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
8967 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
8969 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
8970 (unsigned int) buf
->len
);
8972 if (has_lock
&& !idr_is_empty(&ctx
->personality_idr
)) {
8973 seq_printf(m
, "Personalities:\n");
8974 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
8976 seq_printf(m
, "PollList:\n");
8977 spin_lock_irq(&ctx
->completion_lock
);
8978 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
8979 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
8980 struct io_kiocb
*req
;
8982 hlist_for_each_entry(req
, list
, hash_node
)
8983 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
8984 req
->task
->task_works
!= NULL
);
8986 spin_unlock_irq(&ctx
->completion_lock
);
8988 mutex_unlock(&ctx
->uring_lock
);
8991 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
8993 struct io_ring_ctx
*ctx
= f
->private_data
;
8995 if (percpu_ref_tryget(&ctx
->refs
)) {
8996 __io_uring_show_fdinfo(ctx
, m
);
8997 percpu_ref_put(&ctx
->refs
);
9002 static const struct file_operations io_uring_fops
= {
9003 .release
= io_uring_release
,
9004 .flush
= io_uring_flush
,
9005 .mmap
= io_uring_mmap
,
9007 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9008 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9010 .poll
= io_uring_poll
,
9011 .fasync
= io_uring_fasync
,
9012 #ifdef CONFIG_PROC_FS
9013 .show_fdinfo
= io_uring_show_fdinfo
,
9017 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9018 struct io_uring_params
*p
)
9020 struct io_rings
*rings
;
9021 size_t size
, sq_array_offset
;
9023 /* make sure these are sane, as we already accounted them */
9024 ctx
->sq_entries
= p
->sq_entries
;
9025 ctx
->cq_entries
= p
->cq_entries
;
9027 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9028 if (size
== SIZE_MAX
)
9031 rings
= io_mem_alloc(size
);
9036 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9037 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9038 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9039 rings
->sq_ring_entries
= p
->sq_entries
;
9040 rings
->cq_ring_entries
= p
->cq_entries
;
9041 ctx
->sq_mask
= rings
->sq_ring_mask
;
9042 ctx
->cq_mask
= rings
->cq_ring_mask
;
9044 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9045 if (size
== SIZE_MAX
) {
9046 io_mem_free(ctx
->rings
);
9051 ctx
->sq_sqes
= io_mem_alloc(size
);
9052 if (!ctx
->sq_sqes
) {
9053 io_mem_free(ctx
->rings
);
9062 * Allocate an anonymous fd, this is what constitutes the application
9063 * visible backing of an io_uring instance. The application mmaps this
9064 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9065 * we have to tie this fd to a socket for file garbage collection purposes.
9067 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
9072 #if defined(CONFIG_UNIX)
9073 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9079 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9083 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9084 O_RDWR
| O_CLOEXEC
);
9088 ret
= PTR_ERR(file
);
9092 #if defined(CONFIG_UNIX)
9093 ctx
->ring_sock
->file
= file
;
9095 if (unlikely(io_uring_add_task_file(file
))) {
9096 file
= ERR_PTR(-ENOMEM
);
9099 fd_install(ret
, file
);
9102 #if defined(CONFIG_UNIX)
9103 sock_release(ctx
->ring_sock
);
9104 ctx
->ring_sock
= NULL
;
9109 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9110 struct io_uring_params __user
*params
)
9112 struct user_struct
*user
= NULL
;
9113 struct io_ring_ctx
*ctx
;
9119 if (entries
> IORING_MAX_ENTRIES
) {
9120 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9122 entries
= IORING_MAX_ENTRIES
;
9126 * Use twice as many entries for the CQ ring. It's possible for the
9127 * application to drive a higher depth than the size of the SQ ring,
9128 * since the sqes are only used at submission time. This allows for
9129 * some flexibility in overcommitting a bit. If the application has
9130 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9131 * of CQ ring entries manually.
9133 p
->sq_entries
= roundup_pow_of_two(entries
);
9134 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9136 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9137 * to a power-of-two, if it isn't already. We do NOT impose
9138 * any cq vs sq ring sizing.
9140 if (p
->cq_entries
< p
->sq_entries
)
9142 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9143 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9145 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9147 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9149 p
->cq_entries
= 2 * p
->sq_entries
;
9152 user
= get_uid(current_user());
9153 limit_mem
= !capable(CAP_IPC_LOCK
);
9156 ret
= __io_account_mem(user
,
9157 ring_pages(p
->sq_entries
, p
->cq_entries
));
9164 ctx
= io_ring_ctx_alloc(p
);
9167 __io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
9172 ctx
->compat
= in_compat_syscall();
9174 ctx
->creds
= get_current_cred();
9176 ctx
->loginuid
= current
->loginuid
;
9177 ctx
->sessionid
= current
->sessionid
;
9179 ctx
->sqo_task
= get_task_struct(current
);
9182 * This is just grabbed for accounting purposes. When a process exits,
9183 * the mm is exited and dropped before the files, hence we need to hang
9184 * on to this mm purely for the purposes of being able to unaccount
9185 * memory (locked/pinned vm). It's not used for anything else.
9187 mmgrab(current
->mm
);
9188 ctx
->mm_account
= current
->mm
;
9190 #ifdef CONFIG_BLK_CGROUP
9192 * The sq thread will belong to the original cgroup it was inited in.
9193 * If the cgroup goes offline (e.g. disabling the io controller), then
9194 * issued bios will be associated with the closest cgroup later in the
9198 ctx
->sqo_blkcg_css
= blkcg_css();
9199 ret
= css_tryget_online(ctx
->sqo_blkcg_css
);
9202 /* don't init against a dying cgroup, have the user try again */
9203 ctx
->sqo_blkcg_css
= NULL
;
9210 * Account memory _before_ installing the file descriptor. Once
9211 * the descriptor is installed, it can get closed at any time. Also
9212 * do this before hitting the general error path, as ring freeing
9213 * will un-account as well.
9215 io_account_mem(ctx
, ring_pages(p
->sq_entries
, p
->cq_entries
),
9217 ctx
->limit_mem
= limit_mem
;
9219 ret
= io_allocate_scq_urings(ctx
, p
);
9223 ret
= io_sq_offload_create(ctx
, p
);
9227 if (!(p
->flags
& IORING_SETUP_R_DISABLED
))
9228 io_sq_offload_start(ctx
);
9230 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9231 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9232 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9233 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9234 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9235 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9236 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9237 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9239 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9240 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9241 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9242 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9243 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9244 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9245 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9246 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9248 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9249 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9250 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9251 IORING_FEAT_POLL_32BITS
;
9253 if (copy_to_user(params
, p
, sizeof(*p
))) {
9259 * Install ring fd as the very last thing, so we don't risk someone
9260 * having closed it before we finish setup
9262 ret
= io_uring_get_fd(ctx
);
9266 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9269 io_ring_ctx_wait_and_kill(ctx
);
9274 * Sets up an aio uring context, and returns the fd. Applications asks for a
9275 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9276 * params structure passed in.
9278 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9280 struct io_uring_params p
;
9283 if (copy_from_user(&p
, params
, sizeof(p
)))
9285 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9290 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9291 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9292 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9293 IORING_SETUP_R_DISABLED
))
9296 return io_uring_create(entries
, &p
, params
);
9299 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9300 struct io_uring_params __user
*, params
)
9302 return io_uring_setup(entries
, params
);
9305 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9307 struct io_uring_probe
*p
;
9311 size
= struct_size(p
, ops
, nr_args
);
9312 if (size
== SIZE_MAX
)
9314 p
= kzalloc(size
, GFP_KERNEL
);
9319 if (copy_from_user(p
, arg
, size
))
9322 if (memchr_inv(p
, 0, size
))
9325 p
->last_op
= IORING_OP_LAST
- 1;
9326 if (nr_args
> IORING_OP_LAST
)
9327 nr_args
= IORING_OP_LAST
;
9329 for (i
= 0; i
< nr_args
; i
++) {
9331 if (!io_op_defs
[i
].not_supported
)
9332 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9337 if (copy_to_user(arg
, p
, size
))
9344 static int io_register_personality(struct io_ring_ctx
*ctx
)
9346 struct io_identity
*id
;
9349 id
= kmalloc(sizeof(*id
), GFP_KERNEL
);
9353 io_init_identity(id
);
9354 id
->creds
= get_current_cred();
9356 ret
= idr_alloc_cyclic(&ctx
->personality_idr
, id
, 1, USHRT_MAX
, GFP_KERNEL
);
9358 put_cred(id
->creds
);
9364 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
9366 struct io_identity
*iod
;
9368 iod
= idr_remove(&ctx
->personality_idr
, id
);
9370 put_cred(iod
->creds
);
9371 if (refcount_dec_and_test(&iod
->count
))
9379 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9380 unsigned int nr_args
)
9382 struct io_uring_restriction
*res
;
9386 /* Restrictions allowed only if rings started disabled */
9387 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9390 /* We allow only a single restrictions registration */
9391 if (ctx
->restrictions
.registered
)
9394 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9397 size
= array_size(nr_args
, sizeof(*res
));
9398 if (size
== SIZE_MAX
)
9401 res
= memdup_user(arg
, size
);
9403 return PTR_ERR(res
);
9407 for (i
= 0; i
< nr_args
; i
++) {
9408 switch (res
[i
].opcode
) {
9409 case IORING_RESTRICTION_REGISTER_OP
:
9410 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9415 __set_bit(res
[i
].register_op
,
9416 ctx
->restrictions
.register_op
);
9418 case IORING_RESTRICTION_SQE_OP
:
9419 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9424 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9426 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9427 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9429 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9430 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9439 /* Reset all restrictions if an error happened */
9441 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9443 ctx
->restrictions
.registered
= true;
9449 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9451 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9454 if (ctx
->restrictions
.registered
)
9455 ctx
->restricted
= 1;
9457 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9459 io_sq_offload_start(ctx
);
9464 static bool io_register_op_must_quiesce(int op
)
9467 case IORING_UNREGISTER_FILES
:
9468 case IORING_REGISTER_FILES_UPDATE
:
9469 case IORING_REGISTER_PROBE
:
9470 case IORING_REGISTER_PERSONALITY
:
9471 case IORING_UNREGISTER_PERSONALITY
:
9478 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
9479 void __user
*arg
, unsigned nr_args
)
9480 __releases(ctx
->uring_lock
)
9481 __acquires(ctx
->uring_lock
)
9486 * We're inside the ring mutex, if the ref is already dying, then
9487 * someone else killed the ctx or is already going through
9488 * io_uring_register().
9490 if (percpu_ref_is_dying(&ctx
->refs
))
9493 if (io_register_op_must_quiesce(opcode
)) {
9494 percpu_ref_kill(&ctx
->refs
);
9497 * Drop uring mutex before waiting for references to exit. If
9498 * another thread is currently inside io_uring_enter() it might
9499 * need to grab the uring_lock to make progress. If we hold it
9500 * here across the drain wait, then we can deadlock. It's safe
9501 * to drop the mutex here, since no new references will come in
9502 * after we've killed the percpu ref.
9504 mutex_unlock(&ctx
->uring_lock
);
9506 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
9509 ret
= io_run_task_work_sig();
9514 mutex_lock(&ctx
->uring_lock
);
9517 percpu_ref_resurrect(&ctx
->refs
);
9522 if (ctx
->restricted
) {
9523 if (opcode
>= IORING_REGISTER_LAST
) {
9528 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
9535 case IORING_REGISTER_BUFFERS
:
9536 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
9538 case IORING_UNREGISTER_BUFFERS
:
9542 ret
= io_sqe_buffer_unregister(ctx
);
9544 case IORING_REGISTER_FILES
:
9545 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
9547 case IORING_UNREGISTER_FILES
:
9551 ret
= io_sqe_files_unregister(ctx
);
9553 case IORING_REGISTER_FILES_UPDATE
:
9554 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
9556 case IORING_REGISTER_EVENTFD
:
9557 case IORING_REGISTER_EVENTFD_ASYNC
:
9561 ret
= io_eventfd_register(ctx
, arg
);
9564 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
9565 ctx
->eventfd_async
= 1;
9567 ctx
->eventfd_async
= 0;
9569 case IORING_UNREGISTER_EVENTFD
:
9573 ret
= io_eventfd_unregister(ctx
);
9575 case IORING_REGISTER_PROBE
:
9577 if (!arg
|| nr_args
> 256)
9579 ret
= io_probe(ctx
, arg
, nr_args
);
9581 case IORING_REGISTER_PERSONALITY
:
9585 ret
= io_register_personality(ctx
);
9587 case IORING_UNREGISTER_PERSONALITY
:
9591 ret
= io_unregister_personality(ctx
, nr_args
);
9593 case IORING_REGISTER_ENABLE_RINGS
:
9597 ret
= io_register_enable_rings(ctx
);
9599 case IORING_REGISTER_RESTRICTIONS
:
9600 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
9608 if (io_register_op_must_quiesce(opcode
)) {
9609 /* bring the ctx back to life */
9610 percpu_ref_reinit(&ctx
->refs
);
9612 reinit_completion(&ctx
->ref_comp
);
9617 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
9618 void __user
*, arg
, unsigned int, nr_args
)
9620 struct io_ring_ctx
*ctx
;
9629 if (f
.file
->f_op
!= &io_uring_fops
)
9632 ctx
= f
.file
->private_data
;
9634 mutex_lock(&ctx
->uring_lock
);
9635 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
9636 mutex_unlock(&ctx
->uring_lock
);
9637 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
9638 ctx
->cq_ev_fd
!= NULL
, ret
);
9644 static int __init
io_uring_init(void)
9646 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
9647 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
9648 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
9651 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
9652 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
9653 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
9654 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
9655 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
9656 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
9657 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
9658 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
9659 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
9660 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
9661 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
9662 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
9663 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
9664 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
9665 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
9666 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
9667 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
9668 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
9669 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
9670 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
9671 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
9672 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
9673 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
9674 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
9675 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
9676 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
9677 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
9678 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
9679 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
9680 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
9681 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
9683 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
9684 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
9685 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
9688 __initcall(io_uring_init
);