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)
107 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
108 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
112 u32 head ____cacheline_aligned_in_smp
;
113 u32 tail ____cacheline_aligned_in_smp
;
117 * This data is shared with the application through the mmap at offsets
118 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
120 * The offsets to the member fields are published through struct
121 * io_sqring_offsets when calling io_uring_setup.
125 * Head and tail offsets into the ring; the offsets need to be
126 * masked to get valid indices.
128 * The kernel controls head of the sq ring and the tail of the cq ring,
129 * and the application controls tail of the sq ring and the head of the
132 struct io_uring sq
, cq
;
134 * Bitmasks to apply to head and tail offsets (constant, equals
137 u32 sq_ring_mask
, cq_ring_mask
;
138 /* Ring sizes (constant, power of 2) */
139 u32 sq_ring_entries
, cq_ring_entries
;
141 * Number of invalid entries dropped by the kernel due to
142 * invalid index stored in array
144 * Written by the kernel, shouldn't be modified by the
145 * application (i.e. get number of "new events" by comparing to
148 * After a new SQ head value was read by the application this
149 * counter includes all submissions that were dropped reaching
150 * the new SQ head (and possibly more).
156 * Written by the kernel, shouldn't be modified by the
159 * The application needs a full memory barrier before checking
160 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
166 * Written by the application, shouldn't be modified by the
171 * Number of completion events lost because the queue was full;
172 * this should be avoided by the application by making sure
173 * there are not more requests pending than there is space in
174 * the completion queue.
176 * Written by the kernel, shouldn't be modified by the
177 * application (i.e. get number of "new events" by comparing to
180 * As completion events come in out of order this counter is not
181 * ordered with any other data.
185 * Ring buffer of completion events.
187 * The kernel writes completion events fresh every time they are
188 * produced, so the application is allowed to modify pending
191 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
194 enum io_uring_cmd_flags
{
195 IO_URING_F_NONBLOCK
= 1,
196 IO_URING_F_COMPLETE_DEFER
= 2,
199 struct io_mapped_ubuf
{
202 struct bio_vec
*bvec
;
203 unsigned int nr_bvecs
;
204 unsigned long acct_pages
;
210 struct list_head list
;
217 struct fixed_rsrc_table
{
221 struct fixed_rsrc_ref_node
{
222 struct percpu_ref refs
;
223 struct list_head node
;
224 struct list_head rsrc_list
;
225 struct fixed_rsrc_data
*rsrc_data
;
226 void (*rsrc_put
)(struct io_ring_ctx
*ctx
,
227 struct io_rsrc_put
*prsrc
);
228 struct llist_node llist
;
232 struct fixed_rsrc_data
{
233 struct fixed_rsrc_table
*table
;
234 struct io_ring_ctx
*ctx
;
236 struct fixed_rsrc_ref_node
*node
;
237 struct percpu_ref refs
;
238 struct completion done
;
242 struct list_head list
;
248 struct io_restriction
{
249 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
250 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
251 u8 sqe_flags_allowed
;
252 u8 sqe_flags_required
;
260 /* ctx's that are using this sqd */
261 struct list_head ctx_list
;
262 struct list_head ctx_new_list
;
263 struct mutex ctx_lock
;
265 struct task_struct
*thread
;
266 struct wait_queue_head wait
;
268 unsigned sq_thread_idle
;
271 #define IO_IOPOLL_BATCH 8
272 #define IO_COMPL_BATCH 32
273 #define IO_REQ_CACHE_SIZE 32
274 #define IO_REQ_ALLOC_BATCH 8
276 struct io_comp_state
{
277 struct io_kiocb
*reqs
[IO_COMPL_BATCH
];
279 unsigned int locked_free_nr
;
280 /* inline/task_work completion list, under ->uring_lock */
281 struct list_head free_list
;
282 /* IRQ completion list, under ->completion_lock */
283 struct list_head locked_free_list
;
286 struct io_submit_state
{
287 struct blk_plug plug
;
290 * io_kiocb alloc cache
292 void *reqs
[IO_REQ_CACHE_SIZE
];
293 unsigned int free_reqs
;
298 * Batch completion logic
300 struct io_comp_state comp
;
303 * File reference cache
307 unsigned int file_refs
;
308 unsigned int ios_left
;
313 struct percpu_ref refs
;
314 } ____cacheline_aligned_in_smp
;
318 unsigned int compat
: 1;
319 unsigned int limit_mem
: 1;
320 unsigned int cq_overflow_flushed
: 1;
321 unsigned int drain_next
: 1;
322 unsigned int eventfd_async
: 1;
323 unsigned int restricted
: 1;
324 unsigned int sqo_dead
: 1;
327 * Ring buffer of indices into array of io_uring_sqe, which is
328 * mmapped by the application using the IORING_OFF_SQES offset.
330 * This indirection could e.g. be used to assign fixed
331 * io_uring_sqe entries to operations and only submit them to
332 * the queue when needed.
334 * The kernel modifies neither the indices array nor the entries
338 unsigned cached_sq_head
;
341 unsigned sq_thread_idle
;
342 unsigned cached_sq_dropped
;
343 unsigned cached_cq_overflow
;
344 unsigned long sq_check_overflow
;
346 struct list_head defer_list
;
347 struct list_head timeout_list
;
348 struct list_head cq_overflow_list
;
350 struct io_uring_sqe
*sq_sqes
;
351 } ____cacheline_aligned_in_smp
;
354 struct mutex uring_lock
;
355 wait_queue_head_t wait
;
356 } ____cacheline_aligned_in_smp
;
358 struct io_submit_state submit_state
;
360 struct io_rings
*rings
;
366 * For SQPOLL usage - we hold a reference to the parent task, so we
367 * have access to the ->files
369 struct task_struct
*sqo_task
;
371 /* Only used for accounting purposes */
372 struct mm_struct
*mm_account
;
374 #ifdef CONFIG_BLK_CGROUP
375 struct cgroup_subsys_state
*sqo_blkcg_css
;
378 struct io_sq_data
*sq_data
; /* if using sq thread polling */
380 struct wait_queue_head sqo_sq_wait
;
381 struct list_head sqd_list
;
384 * If used, fixed file set. Writers must ensure that ->refs is dead,
385 * readers must ensure that ->refs is alive as long as the file* is
386 * used. Only updated through io_uring_register(2).
388 struct fixed_rsrc_data
*file_data
;
389 unsigned nr_user_files
;
391 /* if used, fixed mapped user buffers */
392 unsigned nr_user_bufs
;
393 struct io_mapped_ubuf
*user_bufs
;
395 struct user_struct
*user
;
397 const struct cred
*creds
;
401 unsigned int sessionid
;
404 struct completion ref_comp
;
405 struct completion sq_thread_comp
;
407 #if defined(CONFIG_UNIX)
408 struct socket
*ring_sock
;
411 struct idr io_buffer_idr
;
413 struct idr personality_idr
;
416 unsigned cached_cq_tail
;
419 atomic_t cq_timeouts
;
420 unsigned cq_last_tm_flush
;
421 unsigned long cq_check_overflow
;
422 struct wait_queue_head cq_wait
;
423 struct fasync_struct
*cq_fasync
;
424 struct eventfd_ctx
*cq_ev_fd
;
425 } ____cacheline_aligned_in_smp
;
428 spinlock_t completion_lock
;
431 * ->iopoll_list is protected by the ctx->uring_lock for
432 * io_uring instances that don't use IORING_SETUP_SQPOLL.
433 * For SQPOLL, only the single threaded io_sq_thread() will
434 * manipulate the list, hence no extra locking is needed there.
436 struct list_head iopoll_list
;
437 struct hlist_head
*cancel_hash
;
438 unsigned cancel_hash_bits
;
439 bool poll_multi_file
;
441 spinlock_t inflight_lock
;
442 struct list_head inflight_list
;
443 } ____cacheline_aligned_in_smp
;
445 struct delayed_work rsrc_put_work
;
446 struct llist_head rsrc_put_llist
;
447 struct list_head rsrc_ref_list
;
448 spinlock_t rsrc_ref_lock
;
450 struct io_restriction restrictions
;
452 /* Keep this last, we don't need it for the fast path */
453 struct work_struct exit_work
;
457 * First field must be the file pointer in all the
458 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
460 struct io_poll_iocb
{
462 struct wait_queue_head
*head
;
466 struct wait_queue_entry wait
;
469 struct io_poll_remove
{
479 struct io_timeout_data
{
480 struct io_kiocb
*req
;
481 struct hrtimer timer
;
482 struct timespec64 ts
;
483 enum hrtimer_mode mode
;
488 struct sockaddr __user
*addr
;
489 int __user
*addr_len
;
491 unsigned long nofile
;
511 struct list_head list
;
512 /* head of the link, used by linked timeouts only */
513 struct io_kiocb
*head
;
516 struct io_timeout_rem
{
521 struct timespec64 ts
;
526 /* NOTE: kiocb has the file as the first member, so don't do it here */
534 struct sockaddr __user
*addr
;
541 struct user_msghdr __user
*umsg
;
547 struct io_buffer
*kbuf
;
553 struct filename
*filename
;
555 unsigned long nofile
;
558 struct io_rsrc_update
{
584 struct epoll_event event
;
588 struct file
*file_out
;
589 struct file
*file_in
;
596 struct io_provide_buf
{
610 const char __user
*filename
;
611 struct statx __user
*buffer
;
623 struct filename
*oldpath
;
624 struct filename
*newpath
;
632 struct filename
*filename
;
635 struct io_completion
{
637 struct list_head list
;
641 struct io_async_connect
{
642 struct sockaddr_storage address
;
645 struct io_async_msghdr
{
646 struct iovec fast_iov
[UIO_FASTIOV
];
647 /* points to an allocated iov, if NULL we use fast_iov instead */
648 struct iovec
*free_iov
;
649 struct sockaddr __user
*uaddr
;
651 struct sockaddr_storage addr
;
655 struct iovec fast_iov
[UIO_FASTIOV
];
656 const struct iovec
*free_iovec
;
657 struct iov_iter iter
;
659 struct wait_page_queue wpq
;
663 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
664 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
665 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
666 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
667 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
668 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
674 REQ_F_LINK_TIMEOUT_BIT
,
676 REQ_F_NEED_CLEANUP_BIT
,
678 REQ_F_BUFFER_SELECTED_BIT
,
679 REQ_F_NO_FILE_TABLE_BIT
,
680 REQ_F_WORK_INITIALIZED_BIT
,
681 REQ_F_LTIMEOUT_ACTIVE_BIT
,
682 REQ_F_COMPLETE_INLINE_BIT
,
684 /* not a real bit, just to check we're not overflowing the space */
690 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
691 /* drain existing IO first */
692 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
694 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
695 /* doesn't sever on completion < 0 */
696 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
698 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
699 /* IOSQE_BUFFER_SELECT */
700 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
702 /* fail rest of links */
703 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
704 /* on inflight list */
705 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
706 /* read/write uses file position */
707 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
708 /* must not punt to workers */
709 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
710 /* has or had linked timeout */
711 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
713 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
715 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
716 /* already went through poll handler */
717 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
718 /* buffer already selected */
719 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
720 /* doesn't need file table for this request */
721 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
722 /* io_wq_work is initialized */
723 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
724 /* linked timeout is active, i.e. prepared by link's head */
725 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
726 /* completion is deferred through io_comp_state */
727 REQ_F_COMPLETE_INLINE
= BIT(REQ_F_COMPLETE_INLINE_BIT
),
731 struct io_poll_iocb poll
;
732 struct io_poll_iocb
*double_poll
;
735 struct io_task_work
{
736 struct io_wq_work_node node
;
737 task_work_func_t func
;
741 * NOTE! Each of the iocb union members has the file pointer
742 * as the first entry in their struct definition. So you can
743 * access the file pointer through any of the sub-structs,
744 * or directly as just 'ki_filp' in this struct.
750 struct io_poll_iocb poll
;
751 struct io_poll_remove poll_remove
;
752 struct io_accept accept
;
754 struct io_cancel cancel
;
755 struct io_timeout timeout
;
756 struct io_timeout_rem timeout_rem
;
757 struct io_connect connect
;
758 struct io_sr_msg sr_msg
;
760 struct io_close close
;
761 struct io_rsrc_update rsrc_update
;
762 struct io_fadvise fadvise
;
763 struct io_madvise madvise
;
764 struct io_epoll epoll
;
765 struct io_splice splice
;
766 struct io_provide_buf pbuf
;
767 struct io_statx statx
;
768 struct io_shutdown shutdown
;
769 struct io_rename rename
;
770 struct io_unlink unlink
;
771 /* use only after cleaning per-op data, see io_clean_op() */
772 struct io_completion
compl;
775 /* opcode allocated if it needs to store data for async defer */
778 /* polled IO has completed */
784 struct io_ring_ctx
*ctx
;
787 struct task_struct
*task
;
790 struct io_kiocb
*link
;
791 struct percpu_ref
*fixed_rsrc_refs
;
794 * 1. used with ctx->iopoll_list with reads/writes
795 * 2. to track reqs with ->files (see io_op_def::file_table)
797 struct list_head inflight_entry
;
799 struct io_task_work io_task_work
;
800 struct callback_head task_work
;
802 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
803 struct hlist_node hash_node
;
804 struct async_poll
*apoll
;
805 struct io_wq_work work
;
808 struct io_defer_entry
{
809 struct list_head list
;
810 struct io_kiocb
*req
;
815 /* needs req->file assigned */
816 unsigned needs_file
: 1;
817 /* hash wq insertion if file is a regular file */
818 unsigned hash_reg_file
: 1;
819 /* unbound wq insertion if file is a non-regular file */
820 unsigned unbound_nonreg_file
: 1;
821 /* opcode is not supported by this kernel */
822 unsigned not_supported
: 1;
823 /* set if opcode supports polled "wait" */
825 unsigned pollout
: 1;
826 /* op supports buffer selection */
827 unsigned buffer_select
: 1;
828 /* must always have async data allocated */
829 unsigned needs_async_data
: 1;
830 /* should block plug */
832 /* size of async data needed, if any */
833 unsigned short async_size
;
837 static const struct io_op_def io_op_defs
[] = {
838 [IORING_OP_NOP
] = {},
839 [IORING_OP_READV
] = {
841 .unbound_nonreg_file
= 1,
844 .needs_async_data
= 1,
846 .async_size
= sizeof(struct io_async_rw
),
847 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
849 [IORING_OP_WRITEV
] = {
852 .unbound_nonreg_file
= 1,
854 .needs_async_data
= 1,
856 .async_size
= sizeof(struct io_async_rw
),
857 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
860 [IORING_OP_FSYNC
] = {
862 .work_flags
= IO_WQ_WORK_BLKCG
,
864 [IORING_OP_READ_FIXED
] = {
866 .unbound_nonreg_file
= 1,
869 .async_size
= sizeof(struct io_async_rw
),
870 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
872 [IORING_OP_WRITE_FIXED
] = {
875 .unbound_nonreg_file
= 1,
878 .async_size
= sizeof(struct io_async_rw
),
879 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
|
882 [IORING_OP_POLL_ADD
] = {
884 .unbound_nonreg_file
= 1,
886 [IORING_OP_POLL_REMOVE
] = {},
887 [IORING_OP_SYNC_FILE_RANGE
] = {
889 .work_flags
= IO_WQ_WORK_BLKCG
,
891 [IORING_OP_SENDMSG
] = {
893 .unbound_nonreg_file
= 1,
895 .needs_async_data
= 1,
896 .async_size
= sizeof(struct io_async_msghdr
),
897 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
899 [IORING_OP_RECVMSG
] = {
901 .unbound_nonreg_file
= 1,
904 .needs_async_data
= 1,
905 .async_size
= sizeof(struct io_async_msghdr
),
906 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
908 [IORING_OP_TIMEOUT
] = {
909 .needs_async_data
= 1,
910 .async_size
= sizeof(struct io_timeout_data
),
911 .work_flags
= IO_WQ_WORK_MM
,
913 [IORING_OP_TIMEOUT_REMOVE
] = {
914 /* used by timeout updates' prep() */
915 .work_flags
= IO_WQ_WORK_MM
,
917 [IORING_OP_ACCEPT
] = {
919 .unbound_nonreg_file
= 1,
921 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
,
923 [IORING_OP_ASYNC_CANCEL
] = {},
924 [IORING_OP_LINK_TIMEOUT
] = {
925 .needs_async_data
= 1,
926 .async_size
= sizeof(struct io_timeout_data
),
927 .work_flags
= IO_WQ_WORK_MM
,
929 [IORING_OP_CONNECT
] = {
931 .unbound_nonreg_file
= 1,
933 .needs_async_data
= 1,
934 .async_size
= sizeof(struct io_async_connect
),
935 .work_flags
= IO_WQ_WORK_MM
,
937 [IORING_OP_FALLOCATE
] = {
939 .work_flags
= IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FSIZE
,
941 [IORING_OP_OPENAT
] = {
942 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
|
943 IO_WQ_WORK_FS
| IO_WQ_WORK_MM
,
945 [IORING_OP_CLOSE
] = {
946 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
,
948 [IORING_OP_FILES_UPDATE
] = {
949 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
,
951 [IORING_OP_STATX
] = {
952 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
|
953 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
957 .unbound_nonreg_file
= 1,
961 .async_size
= sizeof(struct io_async_rw
),
962 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
964 [IORING_OP_WRITE
] = {
966 .unbound_nonreg_file
= 1,
969 .async_size
= sizeof(struct io_async_rw
),
970 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
973 [IORING_OP_FADVISE
] = {
975 .work_flags
= IO_WQ_WORK_BLKCG
,
977 [IORING_OP_MADVISE
] = {
978 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
982 .unbound_nonreg_file
= 1,
984 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
988 .unbound_nonreg_file
= 1,
991 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
993 [IORING_OP_OPENAT2
] = {
994 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_FS
|
995 IO_WQ_WORK_BLKCG
| IO_WQ_WORK_MM
,
997 [IORING_OP_EPOLL_CTL
] = {
998 .unbound_nonreg_file
= 1,
999 .work_flags
= IO_WQ_WORK_FILES
,
1001 [IORING_OP_SPLICE
] = {
1004 .unbound_nonreg_file
= 1,
1005 .work_flags
= IO_WQ_WORK_BLKCG
,
1007 [IORING_OP_PROVIDE_BUFFERS
] = {},
1008 [IORING_OP_REMOVE_BUFFERS
] = {},
1012 .unbound_nonreg_file
= 1,
1014 [IORING_OP_SHUTDOWN
] = {
1017 [IORING_OP_RENAMEAT
] = {
1018 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
|
1019 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
1021 [IORING_OP_UNLINKAT
] = {
1022 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
|
1023 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
1027 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
1028 struct task_struct
*task
,
1029 struct files_struct
*files
);
1030 static void destroy_fixed_rsrc_ref_node(struct fixed_rsrc_ref_node
*ref_node
);
1031 static struct fixed_rsrc_ref_node
*alloc_fixed_rsrc_ref_node(
1032 struct io_ring_ctx
*ctx
);
1033 static void init_fixed_file_ref_node(struct io_ring_ctx
*ctx
,
1034 struct fixed_rsrc_ref_node
*ref_node
);
1036 static bool io_rw_reissue(struct io_kiocb
*req
);
1037 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
1038 static void io_put_req(struct io_kiocb
*req
);
1039 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
1040 static void io_double_put_req(struct io_kiocb
*req
);
1041 static void io_dismantle_req(struct io_kiocb
*req
);
1042 static void io_put_task(struct task_struct
*task
, int nr
);
1043 static void io_queue_next(struct io_kiocb
*req
);
1044 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
1045 static void __io_queue_linked_timeout(struct io_kiocb
*req
);
1046 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1047 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
1048 struct io_uring_rsrc_update
*ip
,
1050 static void __io_clean_op(struct io_kiocb
*req
);
1051 static struct file
*io_file_get(struct io_submit_state
*state
,
1052 struct io_kiocb
*req
, int fd
, bool fixed
);
1053 static void __io_queue_sqe(struct io_kiocb
*req
);
1054 static void io_rsrc_put_work(struct work_struct
*work
);
1056 static int io_import_iovec(int rw
, struct io_kiocb
*req
, struct iovec
**iovec
,
1057 struct iov_iter
*iter
, bool needs_lock
);
1058 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
1059 const struct iovec
*fast_iov
,
1060 struct iov_iter
*iter
, bool force
);
1061 static void io_req_task_queue(struct io_kiocb
*req
);
1062 static void io_submit_flush_completions(struct io_comp_state
*cs
,
1063 struct io_ring_ctx
*ctx
);
1065 static struct kmem_cache
*req_cachep
;
1067 static const struct file_operations io_uring_fops
;
1069 struct sock
*io_uring_get_socket(struct file
*file
)
1071 #if defined(CONFIG_UNIX)
1072 if (file
->f_op
== &io_uring_fops
) {
1073 struct io_ring_ctx
*ctx
= file
->private_data
;
1075 return ctx
->ring_sock
->sk
;
1080 EXPORT_SYMBOL(io_uring_get_socket
);
1082 #define io_for_each_link(pos, head) \
1083 for (pos = (head); pos; pos = pos->link)
1085 static inline void io_clean_op(struct io_kiocb
*req
)
1087 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
))
1091 static inline void io_set_resource_node(struct io_kiocb
*req
)
1093 struct io_ring_ctx
*ctx
= req
->ctx
;
1095 if (!req
->fixed_rsrc_refs
) {
1096 req
->fixed_rsrc_refs
= &ctx
->file_data
->node
->refs
;
1097 percpu_ref_get(req
->fixed_rsrc_refs
);
1101 static bool io_match_task(struct io_kiocb
*head
,
1102 struct task_struct
*task
,
1103 struct files_struct
*files
)
1105 struct io_kiocb
*req
;
1107 if (task
&& head
->task
!= task
) {
1108 /* in terms of cancelation, always match if req task is dead */
1109 if (head
->task
->flags
& PF_EXITING
)
1116 io_for_each_link(req
, head
) {
1117 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1119 if (req
->file
&& req
->file
->f_op
== &io_uring_fops
)
1121 if ((req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1122 req
->work
.identity
->files
== files
)
1128 static void io_sq_thread_drop_mm_files(void)
1130 struct files_struct
*files
= current
->files
;
1131 struct mm_struct
*mm
= current
->mm
;
1134 kthread_unuse_mm(mm
);
1139 struct nsproxy
*nsproxy
= current
->nsproxy
;
1142 current
->files
= NULL
;
1143 current
->nsproxy
= NULL
;
1144 task_unlock(current
);
1145 put_files_struct(files
);
1146 put_nsproxy(nsproxy
);
1150 static int __io_sq_thread_acquire_files(struct io_ring_ctx
*ctx
)
1152 if (!current
->files
) {
1153 struct files_struct
*files
;
1154 struct nsproxy
*nsproxy
;
1156 task_lock(ctx
->sqo_task
);
1157 files
= ctx
->sqo_task
->files
;
1159 task_unlock(ctx
->sqo_task
);
1162 atomic_inc(&files
->count
);
1163 get_nsproxy(ctx
->sqo_task
->nsproxy
);
1164 nsproxy
= ctx
->sqo_task
->nsproxy
;
1165 task_unlock(ctx
->sqo_task
);
1168 current
->files
= files
;
1169 current
->nsproxy
= nsproxy
;
1170 task_unlock(current
);
1175 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
1177 struct mm_struct
*mm
;
1182 task_lock(ctx
->sqo_task
);
1183 mm
= ctx
->sqo_task
->mm
;
1184 if (unlikely(!mm
|| !mmget_not_zero(mm
)))
1186 task_unlock(ctx
->sqo_task
);
1196 static int __io_sq_thread_acquire_mm_files(struct io_ring_ctx
*ctx
,
1197 struct io_kiocb
*req
)
1199 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1202 if (def
->work_flags
& IO_WQ_WORK_MM
) {
1203 ret
= __io_sq_thread_acquire_mm(ctx
);
1208 if (def
->needs_file
|| (def
->work_flags
& IO_WQ_WORK_FILES
)) {
1209 ret
= __io_sq_thread_acquire_files(ctx
);
1217 static inline int io_sq_thread_acquire_mm_files(struct io_ring_ctx
*ctx
,
1218 struct io_kiocb
*req
)
1220 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
))
1222 return __io_sq_thread_acquire_mm_files(ctx
, req
);
1225 static void io_sq_thread_associate_blkcg(struct io_ring_ctx
*ctx
,
1226 struct cgroup_subsys_state
**cur_css
)
1229 #ifdef CONFIG_BLK_CGROUP
1230 /* puts the old one when swapping */
1231 if (*cur_css
!= ctx
->sqo_blkcg_css
) {
1232 kthread_associate_blkcg(ctx
->sqo_blkcg_css
);
1233 *cur_css
= ctx
->sqo_blkcg_css
;
1238 static void io_sq_thread_unassociate_blkcg(void)
1240 #ifdef CONFIG_BLK_CGROUP
1241 kthread_associate_blkcg(NULL
);
1245 static inline void req_set_fail_links(struct io_kiocb
*req
)
1247 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1248 req
->flags
|= REQ_F_FAIL_LINK
;
1252 * None of these are dereferenced, they are simply used to check if any of
1253 * them have changed. If we're under current and check they are still the
1254 * same, we're fine to grab references to them for actual out-of-line use.
1256 static void io_init_identity(struct io_identity
*id
)
1258 id
->files
= current
->files
;
1259 id
->mm
= current
->mm
;
1260 #ifdef CONFIG_BLK_CGROUP
1262 id
->blkcg_css
= blkcg_css();
1265 id
->creds
= current_cred();
1266 id
->nsproxy
= current
->nsproxy
;
1267 id
->fs
= current
->fs
;
1268 id
->fsize
= rlimit(RLIMIT_FSIZE
);
1270 id
->loginuid
= current
->loginuid
;
1271 id
->sessionid
= current
->sessionid
;
1273 refcount_set(&id
->count
, 1);
1276 static inline void __io_req_init_async(struct io_kiocb
*req
)
1278 memset(&req
->work
, 0, sizeof(req
->work
));
1279 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1283 * Note: must call io_req_init_async() for the first time you
1284 * touch any members of io_wq_work.
1286 static inline void io_req_init_async(struct io_kiocb
*req
)
1288 struct io_uring_task
*tctx
= current
->io_uring
;
1290 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1293 __io_req_init_async(req
);
1295 /* Grab a ref if this isn't our static identity */
1296 req
->work
.identity
= tctx
->identity
;
1297 if (tctx
->identity
!= &tctx
->__identity
)
1298 refcount_inc(&req
->work
.identity
->count
);
1301 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1303 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1305 complete(&ctx
->ref_comp
);
1308 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1310 return !req
->timeout
.off
;
1313 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1315 struct io_ring_ctx
*ctx
;
1318 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1323 * Use 5 bits less than the max cq entries, that should give us around
1324 * 32 entries per hash list if totally full and uniformly spread.
1326 hash_bits
= ilog2(p
->cq_entries
);
1330 ctx
->cancel_hash_bits
= hash_bits
;
1331 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1333 if (!ctx
->cancel_hash
)
1335 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1337 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1338 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1341 ctx
->flags
= p
->flags
;
1342 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1343 INIT_LIST_HEAD(&ctx
->sqd_list
);
1344 init_waitqueue_head(&ctx
->cq_wait
);
1345 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1346 init_completion(&ctx
->ref_comp
);
1347 init_completion(&ctx
->sq_thread_comp
);
1348 idr_init(&ctx
->io_buffer_idr
);
1349 idr_init(&ctx
->personality_idr
);
1350 mutex_init(&ctx
->uring_lock
);
1351 init_waitqueue_head(&ctx
->wait
);
1352 spin_lock_init(&ctx
->completion_lock
);
1353 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1354 INIT_LIST_HEAD(&ctx
->defer_list
);
1355 INIT_LIST_HEAD(&ctx
->timeout_list
);
1356 spin_lock_init(&ctx
->inflight_lock
);
1357 INIT_LIST_HEAD(&ctx
->inflight_list
);
1358 spin_lock_init(&ctx
->rsrc_ref_lock
);
1359 INIT_LIST_HEAD(&ctx
->rsrc_ref_list
);
1360 INIT_DELAYED_WORK(&ctx
->rsrc_put_work
, io_rsrc_put_work
);
1361 init_llist_head(&ctx
->rsrc_put_llist
);
1362 INIT_LIST_HEAD(&ctx
->submit_state
.comp
.free_list
);
1363 INIT_LIST_HEAD(&ctx
->submit_state
.comp
.locked_free_list
);
1366 kfree(ctx
->cancel_hash
);
1371 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1373 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1374 struct io_ring_ctx
*ctx
= req
->ctx
;
1376 return seq
!= ctx
->cached_cq_tail
1377 + READ_ONCE(ctx
->cached_cq_overflow
);
1383 static void io_put_identity(struct io_uring_task
*tctx
, struct io_kiocb
*req
)
1385 if (req
->work
.identity
== &tctx
->__identity
)
1387 if (refcount_dec_and_test(&req
->work
.identity
->count
))
1388 kfree(req
->work
.identity
);
1391 static void io_req_clean_work(struct io_kiocb
*req
)
1393 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1396 if (req
->work
.flags
& IO_WQ_WORK_MM
)
1397 mmdrop(req
->work
.identity
->mm
);
1398 #ifdef CONFIG_BLK_CGROUP
1399 if (req
->work
.flags
& IO_WQ_WORK_BLKCG
)
1400 css_put(req
->work
.identity
->blkcg_css
);
1402 if (req
->work
.flags
& IO_WQ_WORK_CREDS
)
1403 put_cred(req
->work
.identity
->creds
);
1404 if (req
->work
.flags
& IO_WQ_WORK_FS
) {
1405 struct fs_struct
*fs
= req
->work
.identity
->fs
;
1407 spin_lock(&req
->work
.identity
->fs
->lock
);
1410 spin_unlock(&req
->work
.identity
->fs
->lock
);
1414 if (req
->work
.flags
& IO_WQ_WORK_FILES
) {
1415 put_files_struct(req
->work
.identity
->files
);
1416 put_nsproxy(req
->work
.identity
->nsproxy
);
1418 if (req
->flags
& REQ_F_INFLIGHT
) {
1419 struct io_ring_ctx
*ctx
= req
->ctx
;
1420 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1421 unsigned long flags
;
1423 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1424 list_del(&req
->inflight_entry
);
1425 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1426 req
->flags
&= ~REQ_F_INFLIGHT
;
1427 if (atomic_read(&tctx
->in_idle
))
1428 wake_up(&tctx
->wait
);
1431 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1432 req
->work
.flags
&= ~(IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
| IO_WQ_WORK_FS
|
1433 IO_WQ_WORK_CREDS
| IO_WQ_WORK_FILES
);
1434 io_put_identity(req
->task
->io_uring
, req
);
1438 * Create a private copy of io_identity, since some fields don't match
1439 * the current context.
1441 static bool io_identity_cow(struct io_kiocb
*req
)
1443 struct io_uring_task
*tctx
= current
->io_uring
;
1444 const struct cred
*creds
= NULL
;
1445 struct io_identity
*id
;
1447 if (req
->work
.flags
& IO_WQ_WORK_CREDS
)
1448 creds
= req
->work
.identity
->creds
;
1450 id
= kmemdup(req
->work
.identity
, sizeof(*id
), GFP_KERNEL
);
1451 if (unlikely(!id
)) {
1452 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1457 * We can safely just re-init the creds we copied Either the field
1458 * matches the current one, or we haven't grabbed it yet. The only
1459 * exception is ->creds, through registered personalities, so handle
1460 * that one separately.
1462 io_init_identity(id
);
1466 /* add one for this request */
1467 refcount_inc(&id
->count
);
1469 /* drop tctx and req identity references, if needed */
1470 if (tctx
->identity
!= &tctx
->__identity
&&
1471 refcount_dec_and_test(&tctx
->identity
->count
))
1472 kfree(tctx
->identity
);
1473 if (req
->work
.identity
!= &tctx
->__identity
&&
1474 refcount_dec_and_test(&req
->work
.identity
->count
))
1475 kfree(req
->work
.identity
);
1477 req
->work
.identity
= id
;
1478 tctx
->identity
= id
;
1482 static void io_req_track_inflight(struct io_kiocb
*req
)
1484 struct io_ring_ctx
*ctx
= req
->ctx
;
1486 if (!(req
->flags
& REQ_F_INFLIGHT
)) {
1487 io_req_init_async(req
);
1488 req
->flags
|= REQ_F_INFLIGHT
;
1490 spin_lock_irq(&ctx
->inflight_lock
);
1491 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
1492 spin_unlock_irq(&ctx
->inflight_lock
);
1496 static bool io_grab_identity(struct io_kiocb
*req
)
1498 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1499 struct io_identity
*id
= req
->work
.identity
;
1501 if (def
->work_flags
& IO_WQ_WORK_FSIZE
) {
1502 if (id
->fsize
!= rlimit(RLIMIT_FSIZE
))
1504 req
->work
.flags
|= IO_WQ_WORK_FSIZE
;
1506 #ifdef CONFIG_BLK_CGROUP
1507 if (!(req
->work
.flags
& IO_WQ_WORK_BLKCG
) &&
1508 (def
->work_flags
& IO_WQ_WORK_BLKCG
)) {
1510 if (id
->blkcg_css
!= blkcg_css()) {
1515 * This should be rare, either the cgroup is dying or the task
1516 * is moving cgroups. Just punt to root for the handful of ios.
1518 if (css_tryget_online(id
->blkcg_css
))
1519 req
->work
.flags
|= IO_WQ_WORK_BLKCG
;
1523 if (!(req
->work
.flags
& IO_WQ_WORK_CREDS
)) {
1524 if (id
->creds
!= current_cred())
1526 get_cred(id
->creds
);
1527 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
1530 if (!uid_eq(current
->loginuid
, id
->loginuid
) ||
1531 current
->sessionid
!= id
->sessionid
)
1534 if (!(req
->work
.flags
& IO_WQ_WORK_FS
) &&
1535 (def
->work_flags
& IO_WQ_WORK_FS
)) {
1536 if (current
->fs
!= id
->fs
)
1538 spin_lock(&id
->fs
->lock
);
1539 if (!id
->fs
->in_exec
) {
1541 req
->work
.flags
|= IO_WQ_WORK_FS
;
1543 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1545 spin_unlock(¤t
->fs
->lock
);
1547 if (!(req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1548 (def
->work_flags
& IO_WQ_WORK_FILES
) &&
1549 !(req
->flags
& REQ_F_NO_FILE_TABLE
)) {
1550 if (id
->files
!= current
->files
||
1551 id
->nsproxy
!= current
->nsproxy
)
1553 atomic_inc(&id
->files
->count
);
1554 get_nsproxy(id
->nsproxy
);
1555 req
->work
.flags
|= IO_WQ_WORK_FILES
;
1556 io_req_track_inflight(req
);
1558 if (!(req
->work
.flags
& IO_WQ_WORK_MM
) &&
1559 (def
->work_flags
& IO_WQ_WORK_MM
)) {
1560 if (id
->mm
!= current
->mm
)
1563 req
->work
.flags
|= IO_WQ_WORK_MM
;
1569 static void io_prep_async_work(struct io_kiocb
*req
)
1571 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1572 struct io_ring_ctx
*ctx
= req
->ctx
;
1574 io_req_init_async(req
);
1576 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1577 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1579 if (req
->flags
& REQ_F_ISREG
) {
1580 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1581 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1583 if (def
->unbound_nonreg_file
)
1584 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1587 /* if we fail grabbing identity, we must COW, regrab, and retry */
1588 if (io_grab_identity(req
))
1591 if (!io_identity_cow(req
))
1594 /* can't fail at this point */
1595 if (!io_grab_identity(req
))
1599 static void io_prep_async_link(struct io_kiocb
*req
)
1601 struct io_kiocb
*cur
;
1603 io_for_each_link(cur
, req
)
1604 io_prep_async_work(cur
);
1607 static struct io_kiocb
*__io_queue_async_work(struct io_kiocb
*req
)
1609 struct io_ring_ctx
*ctx
= req
->ctx
;
1610 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1612 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1613 &req
->work
, req
->flags
);
1614 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1618 static void io_queue_async_work(struct io_kiocb
*req
)
1620 struct io_kiocb
*link
;
1622 /* init ->work of the whole link before punting */
1623 io_prep_async_link(req
);
1624 link
= __io_queue_async_work(req
);
1627 io_queue_linked_timeout(link
);
1630 static void io_kill_timeout(struct io_kiocb
*req
)
1632 struct io_timeout_data
*io
= req
->async_data
;
1635 ret
= hrtimer_try_to_cancel(&io
->timer
);
1637 atomic_set(&req
->ctx
->cq_timeouts
,
1638 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1639 list_del_init(&req
->timeout
.list
);
1640 io_cqring_fill_event(req
, 0);
1641 io_put_req_deferred(req
, 1);
1646 * Returns true if we found and killed one or more timeouts
1648 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
1649 struct files_struct
*files
)
1651 struct io_kiocb
*req
, *tmp
;
1654 spin_lock_irq(&ctx
->completion_lock
);
1655 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
1656 if (io_match_task(req
, tsk
, files
)) {
1657 io_kill_timeout(req
);
1661 spin_unlock_irq(&ctx
->completion_lock
);
1662 return canceled
!= 0;
1665 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1668 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1669 struct io_defer_entry
, list
);
1671 if (req_need_defer(de
->req
, de
->seq
))
1673 list_del_init(&de
->list
);
1674 io_req_task_queue(de
->req
);
1676 } while (!list_empty(&ctx
->defer_list
));
1679 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1683 if (list_empty(&ctx
->timeout_list
))
1686 seq
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
1689 u32 events_needed
, events_got
;
1690 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1691 struct io_kiocb
, timeout
.list
);
1693 if (io_is_timeout_noseq(req
))
1697 * Since seq can easily wrap around over time, subtract
1698 * the last seq at which timeouts were flushed before comparing.
1699 * Assuming not more than 2^31-1 events have happened since,
1700 * these subtractions won't have wrapped, so we can check if
1701 * target is in [last_seq, current_seq] by comparing the two.
1703 events_needed
= req
->timeout
.target_seq
- ctx
->cq_last_tm_flush
;
1704 events_got
= seq
- ctx
->cq_last_tm_flush
;
1705 if (events_got
< events_needed
)
1708 list_del_init(&req
->timeout
.list
);
1709 io_kill_timeout(req
);
1710 } while (!list_empty(&ctx
->timeout_list
));
1712 ctx
->cq_last_tm_flush
= seq
;
1715 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1717 io_flush_timeouts(ctx
);
1719 /* order cqe stores with ring update */
1720 smp_store_release(&ctx
->rings
->cq
.tail
, ctx
->cached_cq_tail
);
1722 if (unlikely(!list_empty(&ctx
->defer_list
)))
1723 __io_queue_deferred(ctx
);
1726 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1728 struct io_rings
*r
= ctx
->rings
;
1730 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1733 static inline unsigned int __io_cqring_events(struct io_ring_ctx
*ctx
)
1735 return ctx
->cached_cq_tail
- READ_ONCE(ctx
->rings
->cq
.head
);
1738 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1740 struct io_rings
*rings
= ctx
->rings
;
1744 * writes to the cq entry need to come after reading head; the
1745 * control dependency is enough as we're using WRITE_ONCE to
1748 if (__io_cqring_events(ctx
) == rings
->cq_ring_entries
)
1751 tail
= ctx
->cached_cq_tail
++;
1752 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1755 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1759 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1761 if (!ctx
->eventfd_async
)
1763 return io_wq_current_is_worker();
1766 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1768 /* see waitqueue_active() comment */
1771 if (waitqueue_active(&ctx
->wait
))
1772 wake_up(&ctx
->wait
);
1773 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1774 wake_up(&ctx
->sq_data
->wait
);
1775 if (io_should_trigger_evfd(ctx
))
1776 eventfd_signal(ctx
->cq_ev_fd
, 1);
1777 if (waitqueue_active(&ctx
->cq_wait
)) {
1778 wake_up_interruptible(&ctx
->cq_wait
);
1779 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1783 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx
*ctx
)
1785 /* see waitqueue_active() comment */
1788 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1789 if (waitqueue_active(&ctx
->wait
))
1790 wake_up(&ctx
->wait
);
1792 if (io_should_trigger_evfd(ctx
))
1793 eventfd_signal(ctx
->cq_ev_fd
, 1);
1794 if (waitqueue_active(&ctx
->cq_wait
)) {
1795 wake_up_interruptible(&ctx
->cq_wait
);
1796 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1800 /* Returns true if there are no backlogged entries after the flush */
1801 static bool __io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1802 struct task_struct
*tsk
,
1803 struct files_struct
*files
)
1805 struct io_rings
*rings
= ctx
->rings
;
1806 struct io_kiocb
*req
, *tmp
;
1807 struct io_uring_cqe
*cqe
;
1808 unsigned long flags
;
1809 bool all_flushed
, posted
;
1812 if (!force
&& __io_cqring_events(ctx
) == rings
->cq_ring_entries
)
1816 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1817 list_for_each_entry_safe(req
, tmp
, &ctx
->cq_overflow_list
, compl.list
) {
1818 if (!io_match_task(req
, tsk
, files
))
1821 cqe
= io_get_cqring(ctx
);
1825 list_move(&req
->compl.list
, &list
);
1827 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1828 WRITE_ONCE(cqe
->res
, req
->result
);
1829 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1831 ctx
->cached_cq_overflow
++;
1832 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1833 ctx
->cached_cq_overflow
);
1838 all_flushed
= list_empty(&ctx
->cq_overflow_list
);
1840 clear_bit(0, &ctx
->sq_check_overflow
);
1841 clear_bit(0, &ctx
->cq_check_overflow
);
1842 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1846 io_commit_cqring(ctx
);
1847 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1849 io_cqring_ev_posted(ctx
);
1851 while (!list_empty(&list
)) {
1852 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1853 list_del(&req
->compl.list
);
1860 static void io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1861 struct task_struct
*tsk
,
1862 struct files_struct
*files
)
1864 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1865 /* iopoll syncs against uring_lock, not completion_lock */
1866 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1867 mutex_lock(&ctx
->uring_lock
);
1868 __io_cqring_overflow_flush(ctx
, force
, tsk
, files
);
1869 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1870 mutex_unlock(&ctx
->uring_lock
);
1874 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1876 struct io_ring_ctx
*ctx
= req
->ctx
;
1877 struct io_uring_cqe
*cqe
;
1879 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1882 * If we can't get a cq entry, userspace overflowed the
1883 * submission (by quite a lot). Increment the overflow count in
1886 cqe
= io_get_cqring(ctx
);
1888 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1889 WRITE_ONCE(cqe
->res
, res
);
1890 WRITE_ONCE(cqe
->flags
, cflags
);
1891 } else if (ctx
->cq_overflow_flushed
||
1892 atomic_read(&req
->task
->io_uring
->in_idle
)) {
1894 * If we're in ring overflow flush mode, or in task cancel mode,
1895 * then we cannot store the request for later flushing, we need
1896 * to drop it on the floor.
1898 ctx
->cached_cq_overflow
++;
1899 WRITE_ONCE(ctx
->rings
->cq_overflow
, ctx
->cached_cq_overflow
);
1901 if (list_empty(&ctx
->cq_overflow_list
)) {
1902 set_bit(0, &ctx
->sq_check_overflow
);
1903 set_bit(0, &ctx
->cq_check_overflow
);
1904 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1908 req
->compl.cflags
= cflags
;
1909 refcount_inc(&req
->refs
);
1910 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1914 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1916 __io_cqring_fill_event(req
, res
, 0);
1919 static inline void io_req_complete_post(struct io_kiocb
*req
, long res
,
1920 unsigned int cflags
)
1922 struct io_ring_ctx
*ctx
= req
->ctx
;
1923 unsigned long flags
;
1925 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1926 __io_cqring_fill_event(req
, res
, cflags
);
1927 io_commit_cqring(ctx
);
1929 * If we're the last reference to this request, add to our locked
1932 if (refcount_dec_and_test(&req
->refs
)) {
1933 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
1935 io_dismantle_req(req
);
1936 io_put_task(req
->task
, 1);
1937 list_add(&req
->compl.list
, &cs
->locked_free_list
);
1938 cs
->locked_free_nr
++;
1941 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1943 io_cqring_ev_posted(ctx
);
1946 percpu_ref_put(&ctx
->refs
);
1950 static void io_req_complete_state(struct io_kiocb
*req
, long res
,
1951 unsigned int cflags
)
1955 req
->compl.cflags
= cflags
;
1956 req
->flags
|= REQ_F_COMPLETE_INLINE
;
1959 static inline void __io_req_complete(struct io_kiocb
*req
, unsigned issue_flags
,
1960 long res
, unsigned cflags
)
1962 if (issue_flags
& IO_URING_F_COMPLETE_DEFER
)
1963 io_req_complete_state(req
, res
, cflags
);
1965 io_req_complete_post(req
, res
, cflags
);
1968 static inline void io_req_complete(struct io_kiocb
*req
, long res
)
1970 __io_req_complete(req
, 0, res
, 0);
1973 static bool io_flush_cached_reqs(struct io_ring_ctx
*ctx
)
1975 struct io_submit_state
*state
= &ctx
->submit_state
;
1976 struct io_comp_state
*cs
= &state
->comp
;
1977 struct io_kiocb
*req
= NULL
;
1980 * If we have more than a batch's worth of requests in our IRQ side
1981 * locked cache, grab the lock and move them over to our submission
1984 if (READ_ONCE(cs
->locked_free_nr
) > IO_COMPL_BATCH
) {
1985 spin_lock_irq(&ctx
->completion_lock
);
1986 list_splice_init(&cs
->locked_free_list
, &cs
->free_list
);
1987 cs
->locked_free_nr
= 0;
1988 spin_unlock_irq(&ctx
->completion_lock
);
1991 while (!list_empty(&cs
->free_list
)) {
1992 req
= list_first_entry(&cs
->free_list
, struct io_kiocb
,
1994 list_del(&req
->compl.list
);
1995 state
->reqs
[state
->free_reqs
++] = req
;
1996 if (state
->free_reqs
== ARRAY_SIZE(state
->reqs
))
2003 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
)
2005 struct io_submit_state
*state
= &ctx
->submit_state
;
2007 BUILD_BUG_ON(IO_REQ_ALLOC_BATCH
> ARRAY_SIZE(state
->reqs
));
2009 if (!state
->free_reqs
) {
2010 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
2013 if (io_flush_cached_reqs(ctx
))
2016 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, IO_REQ_ALLOC_BATCH
,
2020 * Bulk alloc is all-or-nothing. If we fail to get a batch,
2021 * retry single alloc to be on the safe side.
2023 if (unlikely(ret
<= 0)) {
2024 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
2025 if (!state
->reqs
[0])
2029 state
->free_reqs
= ret
;
2033 return state
->reqs
[state
->free_reqs
];
2036 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
2043 static void io_dismantle_req(struct io_kiocb
*req
)
2047 if (req
->async_data
)
2048 kfree(req
->async_data
);
2050 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
2051 if (req
->fixed_rsrc_refs
)
2052 percpu_ref_put(req
->fixed_rsrc_refs
);
2053 io_req_clean_work(req
);
2056 static inline void io_put_task(struct task_struct
*task
, int nr
)
2058 struct io_uring_task
*tctx
= task
->io_uring
;
2060 percpu_counter_sub(&tctx
->inflight
, nr
);
2061 if (unlikely(atomic_read(&tctx
->in_idle
)))
2062 wake_up(&tctx
->wait
);
2063 put_task_struct_many(task
, nr
);
2066 static void __io_free_req(struct io_kiocb
*req
)
2068 struct io_ring_ctx
*ctx
= req
->ctx
;
2070 io_dismantle_req(req
);
2071 io_put_task(req
->task
, 1);
2073 kmem_cache_free(req_cachep
, req
);
2074 percpu_ref_put(&ctx
->refs
);
2077 static inline void io_remove_next_linked(struct io_kiocb
*req
)
2079 struct io_kiocb
*nxt
= req
->link
;
2081 req
->link
= nxt
->link
;
2085 static void io_kill_linked_timeout(struct io_kiocb
*req
)
2087 struct io_ring_ctx
*ctx
= req
->ctx
;
2088 struct io_kiocb
*link
;
2089 bool cancelled
= false;
2090 unsigned long flags
;
2092 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
2096 * Can happen if a linked timeout fired and link had been like
2097 * req -> link t-out -> link t-out [-> ...]
2099 if (link
&& (link
->flags
& REQ_F_LTIMEOUT_ACTIVE
)) {
2100 struct io_timeout_data
*io
= link
->async_data
;
2103 io_remove_next_linked(req
);
2104 link
->timeout
.head
= NULL
;
2105 ret
= hrtimer_try_to_cancel(&io
->timer
);
2107 io_cqring_fill_event(link
, -ECANCELED
);
2108 io_commit_cqring(ctx
);
2112 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
2113 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
2116 io_cqring_ev_posted(ctx
);
2122 static void io_fail_links(struct io_kiocb
*req
)
2124 struct io_kiocb
*link
, *nxt
;
2125 struct io_ring_ctx
*ctx
= req
->ctx
;
2126 unsigned long flags
;
2128 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
2136 trace_io_uring_fail_link(req
, link
);
2137 io_cqring_fill_event(link
, -ECANCELED
);
2140 * It's ok to free under spinlock as they're not linked anymore,
2141 * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
2144 if (link
->flags
& REQ_F_WORK_INITIALIZED
)
2145 io_put_req_deferred(link
, 2);
2147 io_double_put_req(link
);
2150 io_commit_cqring(ctx
);
2151 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
2153 io_cqring_ev_posted(ctx
);
2156 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
2158 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
2159 io_kill_linked_timeout(req
);
2162 * If LINK is set, we have dependent requests in this chain. If we
2163 * didn't fail this request, queue the first one up, moving any other
2164 * dependencies to the next request. In case of failure, fail the rest
2167 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
))) {
2168 struct io_kiocb
*nxt
= req
->link
;
2177 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
2179 if (likely(!(req
->flags
& (REQ_F_LINK
|REQ_F_HARDLINK
))))
2181 return __io_req_find_next(req
);
2184 static bool __tctx_task_work(struct io_uring_task
*tctx
)
2186 struct io_ring_ctx
*ctx
= NULL
;
2187 struct io_wq_work_list list
;
2188 struct io_wq_work_node
*node
;
2190 if (wq_list_empty(&tctx
->task_list
))
2193 spin_lock_irq(&tctx
->task_lock
);
2194 list
= tctx
->task_list
;
2195 INIT_WQ_LIST(&tctx
->task_list
);
2196 spin_unlock_irq(&tctx
->task_lock
);
2200 struct io_wq_work_node
*next
= node
->next
;
2201 struct io_ring_ctx
*this_ctx
;
2202 struct io_kiocb
*req
;
2204 req
= container_of(node
, struct io_kiocb
, io_task_work
.node
);
2205 this_ctx
= req
->ctx
;
2206 req
->task_work
.func(&req
->task_work
);
2211 } else if (ctx
!= this_ctx
) {
2212 mutex_lock(&ctx
->uring_lock
);
2213 io_submit_flush_completions(&ctx
->submit_state
.comp
, ctx
);
2214 mutex_unlock(&ctx
->uring_lock
);
2219 if (ctx
&& ctx
->submit_state
.comp
.nr
) {
2220 mutex_lock(&ctx
->uring_lock
);
2221 io_submit_flush_completions(&ctx
->submit_state
.comp
, ctx
);
2222 mutex_unlock(&ctx
->uring_lock
);
2225 return list
.first
!= NULL
;
2228 static void tctx_task_work(struct callback_head
*cb
)
2230 struct io_uring_task
*tctx
= container_of(cb
, struct io_uring_task
, task_work
);
2232 while (__tctx_task_work(tctx
))
2235 clear_bit(0, &tctx
->task_state
);
2238 static int io_task_work_add(struct task_struct
*tsk
, struct io_kiocb
*req
,
2239 enum task_work_notify_mode notify
)
2241 struct io_uring_task
*tctx
= tsk
->io_uring
;
2242 struct io_wq_work_node
*node
, *prev
;
2243 unsigned long flags
;
2246 WARN_ON_ONCE(!tctx
);
2248 spin_lock_irqsave(&tctx
->task_lock
, flags
);
2249 wq_list_add_tail(&req
->io_task_work
.node
, &tctx
->task_list
);
2250 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
2252 /* task_work already pending, we're done */
2253 if (test_bit(0, &tctx
->task_state
) ||
2254 test_and_set_bit(0, &tctx
->task_state
))
2257 if (!task_work_add(tsk
, &tctx
->task_work
, notify
))
2261 * Slow path - we failed, find and delete work. if the work is not
2262 * in the list, it got run and we're fine.
2265 spin_lock_irqsave(&tctx
->task_lock
, flags
);
2266 wq_list_for_each(node
, prev
, &tctx
->task_list
) {
2267 if (&req
->io_task_work
.node
== node
) {
2268 wq_list_del(&tctx
->task_list
, node
, prev
);
2273 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
2274 clear_bit(0, &tctx
->task_state
);
2278 static int io_req_task_work_add(struct io_kiocb
*req
)
2280 struct task_struct
*tsk
= req
->task
;
2281 struct io_ring_ctx
*ctx
= req
->ctx
;
2282 enum task_work_notify_mode notify
;
2285 if (tsk
->flags
& PF_EXITING
)
2289 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2290 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2291 * processing task_work. There's no reliable way to tell if TWA_RESUME
2295 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
))
2296 notify
= TWA_SIGNAL
;
2298 ret
= io_task_work_add(tsk
, req
, notify
);
2300 wake_up_process(tsk
);
2305 static void io_req_task_work_add_fallback(struct io_kiocb
*req
,
2306 task_work_func_t cb
)
2308 struct task_struct
*tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2310 init_task_work(&req
->task_work
, cb
);
2311 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2312 wake_up_process(tsk
);
2315 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
2317 struct io_ring_ctx
*ctx
= req
->ctx
;
2319 spin_lock_irq(&ctx
->completion_lock
);
2320 io_cqring_fill_event(req
, error
);
2321 io_commit_cqring(ctx
);
2322 spin_unlock_irq(&ctx
->completion_lock
);
2324 io_cqring_ev_posted(ctx
);
2325 req_set_fail_links(req
);
2326 io_double_put_req(req
);
2329 static void io_req_task_cancel(struct callback_head
*cb
)
2331 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2332 struct io_ring_ctx
*ctx
= req
->ctx
;
2334 __io_req_task_cancel(req
, -ECANCELED
);
2335 percpu_ref_put(&ctx
->refs
);
2338 static void __io_req_task_submit(struct io_kiocb
*req
)
2340 struct io_ring_ctx
*ctx
= req
->ctx
;
2342 /* ctx stays valid until unlock, even if we drop all ours ctx->refs */
2343 mutex_lock(&ctx
->uring_lock
);
2344 if (!ctx
->sqo_dead
&& !(current
->flags
& PF_EXITING
) &&
2345 !io_sq_thread_acquire_mm_files(ctx
, req
))
2346 __io_queue_sqe(req
);
2348 __io_req_task_cancel(req
, -EFAULT
);
2349 mutex_unlock(&ctx
->uring_lock
);
2352 static void io_req_task_submit(struct callback_head
*cb
)
2354 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2356 __io_req_task_submit(req
);
2359 static void io_req_task_queue(struct io_kiocb
*req
)
2363 req
->task_work
.func
= io_req_task_submit
;
2364 ret
= io_req_task_work_add(req
);
2365 if (unlikely(ret
)) {
2366 percpu_ref_get(&req
->ctx
->refs
);
2367 io_req_task_work_add_fallback(req
, io_req_task_cancel
);
2371 static inline void io_queue_next(struct io_kiocb
*req
)
2373 struct io_kiocb
*nxt
= io_req_find_next(req
);
2376 io_req_task_queue(nxt
);
2379 static void io_free_req(struct io_kiocb
*req
)
2386 struct task_struct
*task
;
2391 static inline void io_init_req_batch(struct req_batch
*rb
)
2398 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2399 struct req_batch
*rb
)
2402 io_put_task(rb
->task
, rb
->task_refs
);
2404 percpu_ref_put_many(&ctx
->refs
, rb
->ctx_refs
);
2407 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
,
2408 struct io_submit_state
*state
)
2412 if (req
->task
!= rb
->task
) {
2414 io_put_task(rb
->task
, rb
->task_refs
);
2415 rb
->task
= req
->task
;
2421 io_dismantle_req(req
);
2422 if (state
->free_reqs
!= ARRAY_SIZE(state
->reqs
))
2423 state
->reqs
[state
->free_reqs
++] = req
;
2425 list_add(&req
->compl.list
, &state
->comp
.free_list
);
2428 static void io_submit_flush_completions(struct io_comp_state
*cs
,
2429 struct io_ring_ctx
*ctx
)
2432 struct io_kiocb
*req
;
2433 struct req_batch rb
;
2435 io_init_req_batch(&rb
);
2436 spin_lock_irq(&ctx
->completion_lock
);
2437 for (i
= 0; i
< nr
; i
++) {
2439 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
2441 io_commit_cqring(ctx
);
2442 spin_unlock_irq(&ctx
->completion_lock
);
2444 io_cqring_ev_posted(ctx
);
2445 for (i
= 0; i
< nr
; i
++) {
2448 /* submission and completion refs */
2449 if (refcount_sub_and_test(2, &req
->refs
))
2450 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2453 io_req_free_batch_finish(ctx
, &rb
);
2458 * Drop reference to request, return next in chain (if there is one) if this
2459 * was the last reference to this request.
2461 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2463 struct io_kiocb
*nxt
= NULL
;
2465 if (refcount_dec_and_test(&req
->refs
)) {
2466 nxt
= io_req_find_next(req
);
2472 static void io_put_req(struct io_kiocb
*req
)
2474 if (refcount_dec_and_test(&req
->refs
))
2478 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2480 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2485 static void io_free_req_deferred(struct io_kiocb
*req
)
2489 req
->task_work
.func
= io_put_req_deferred_cb
;
2490 ret
= io_req_task_work_add(req
);
2492 io_req_task_work_add_fallback(req
, io_put_req_deferred_cb
);
2495 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2497 if (refcount_sub_and_test(refs
, &req
->refs
))
2498 io_free_req_deferred(req
);
2501 static void io_double_put_req(struct io_kiocb
*req
)
2503 /* drop both submit and complete references */
2504 if (refcount_sub_and_test(2, &req
->refs
))
2508 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
)
2510 /* See comment at the top of this file */
2512 return __io_cqring_events(ctx
);
2515 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2517 struct io_rings
*rings
= ctx
->rings
;
2519 /* make sure SQ entry isn't read before tail */
2520 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2523 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2525 unsigned int cflags
;
2527 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2528 cflags
|= IORING_CQE_F_BUFFER
;
2529 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2534 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2536 struct io_buffer
*kbuf
;
2538 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2539 return io_put_kbuf(req
, kbuf
);
2542 static inline bool io_run_task_work(void)
2545 * Not safe to run on exiting task, and the task_work handling will
2546 * not add work to such a task.
2548 if (unlikely(current
->flags
& PF_EXITING
))
2550 if (current
->task_works
) {
2551 __set_current_state(TASK_RUNNING
);
2560 * Find and free completed poll iocbs
2562 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2563 struct list_head
*done
)
2565 struct req_batch rb
;
2566 struct io_kiocb
*req
;
2568 /* order with ->result store in io_complete_rw_iopoll() */
2571 io_init_req_batch(&rb
);
2572 while (!list_empty(done
)) {
2575 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2576 list_del(&req
->inflight_entry
);
2578 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2579 req
->iopoll_completed
= 0;
2580 if (io_rw_reissue(req
))
2584 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2585 cflags
= io_put_rw_kbuf(req
);
2587 __io_cqring_fill_event(req
, req
->result
, cflags
);
2590 if (refcount_dec_and_test(&req
->refs
))
2591 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2594 io_commit_cqring(ctx
);
2595 io_cqring_ev_posted_iopoll(ctx
);
2596 io_req_free_batch_finish(ctx
, &rb
);
2599 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2602 struct io_kiocb
*req
, *tmp
;
2608 * Only spin for completions if we don't have multiple devices hanging
2609 * off our complete list, and we're under the requested amount.
2611 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2614 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2615 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2618 * Move completed and retryable entries to our local lists.
2619 * If we find a request that requires polling, break out
2620 * and complete those lists first, if we have entries there.
2622 if (READ_ONCE(req
->iopoll_completed
)) {
2623 list_move_tail(&req
->inflight_entry
, &done
);
2626 if (!list_empty(&done
))
2629 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2633 /* iopoll may have completed current req */
2634 if (READ_ONCE(req
->iopoll_completed
))
2635 list_move_tail(&req
->inflight_entry
, &done
);
2642 if (!list_empty(&done
))
2643 io_iopoll_complete(ctx
, nr_events
, &done
);
2649 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2650 * non-spinning poll check - we'll still enter the driver poll loop, but only
2651 * as a non-spinning completion check.
2653 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2656 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2659 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2662 if (*nr_events
>= min
)
2670 * We can't just wait for polled events to come to us, we have to actively
2671 * find and complete them.
2673 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2675 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2678 mutex_lock(&ctx
->uring_lock
);
2679 while (!list_empty(&ctx
->iopoll_list
)) {
2680 unsigned int nr_events
= 0;
2682 io_do_iopoll(ctx
, &nr_events
, 0);
2684 /* let it sleep and repeat later if can't complete a request */
2688 * Ensure we allow local-to-the-cpu processing to take place,
2689 * in this case we need to ensure that we reap all events.
2690 * Also let task_work, etc. to progress by releasing the mutex
2692 if (need_resched()) {
2693 mutex_unlock(&ctx
->uring_lock
);
2695 mutex_lock(&ctx
->uring_lock
);
2698 mutex_unlock(&ctx
->uring_lock
);
2701 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2703 unsigned int nr_events
= 0;
2704 int iters
= 0, ret
= 0;
2707 * We disallow the app entering submit/complete with polling, but we
2708 * still need to lock the ring to prevent racing with polled issue
2709 * that got punted to a workqueue.
2711 mutex_lock(&ctx
->uring_lock
);
2714 * Don't enter poll loop if we already have events pending.
2715 * If we do, we can potentially be spinning for commands that
2716 * already triggered a CQE (eg in error).
2718 if (test_bit(0, &ctx
->cq_check_overflow
))
2719 __io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
2720 if (io_cqring_events(ctx
))
2724 * If a submit got punted to a workqueue, we can have the
2725 * application entering polling for a command before it gets
2726 * issued. That app will hold the uring_lock for the duration
2727 * of the poll right here, so we need to take a breather every
2728 * now and then to ensure that the issue has a chance to add
2729 * the poll to the issued list. Otherwise we can spin here
2730 * forever, while the workqueue is stuck trying to acquire the
2733 if (!(++iters
& 7)) {
2734 mutex_unlock(&ctx
->uring_lock
);
2736 mutex_lock(&ctx
->uring_lock
);
2739 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2743 } while (min
&& !nr_events
&& !need_resched());
2745 mutex_unlock(&ctx
->uring_lock
);
2749 static void kiocb_end_write(struct io_kiocb
*req
)
2752 * Tell lockdep we inherited freeze protection from submission
2755 if (req
->flags
& REQ_F_ISREG
) {
2756 struct inode
*inode
= file_inode(req
->file
);
2758 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2760 file_end_write(req
->file
);
2764 static bool io_resubmit_prep(struct io_kiocb
*req
)
2766 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2768 struct iov_iter iter
;
2770 /* already prepared */
2771 if (req
->async_data
)
2774 switch (req
->opcode
) {
2775 case IORING_OP_READV
:
2776 case IORING_OP_READ_FIXED
:
2777 case IORING_OP_READ
:
2780 case IORING_OP_WRITEV
:
2781 case IORING_OP_WRITE_FIXED
:
2782 case IORING_OP_WRITE
:
2786 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2791 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2794 return !io_setup_async_rw(req
, iovec
, inline_vecs
, &iter
, false);
2798 static bool io_rw_reissue(struct io_kiocb
*req
)
2801 umode_t mode
= file_inode(req
->file
)->i_mode
;
2804 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2806 if ((req
->flags
& REQ_F_NOWAIT
) || io_wq_current_is_worker())
2809 lockdep_assert_held(&req
->ctx
->uring_lock
);
2811 ret
= io_sq_thread_acquire_mm_files(req
->ctx
, req
);
2813 if (!ret
&& io_resubmit_prep(req
)) {
2814 refcount_inc(&req
->refs
);
2815 io_queue_async_work(req
);
2818 req_set_fail_links(req
);
2823 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2824 unsigned int issue_flags
)
2828 if ((res
== -EAGAIN
|| res
== -EOPNOTSUPP
) && io_rw_reissue(req
))
2830 if (res
!= req
->result
)
2831 req_set_fail_links(req
);
2833 if (req
->rw
.kiocb
.ki_flags
& IOCB_WRITE
)
2834 kiocb_end_write(req
);
2835 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2836 cflags
= io_put_rw_kbuf(req
);
2837 __io_req_complete(req
, issue_flags
, res
, cflags
);
2840 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2842 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2844 __io_complete_rw(req
, res
, res2
, 0);
2847 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2849 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2851 if (kiocb
->ki_flags
& IOCB_WRITE
)
2852 kiocb_end_write(req
);
2854 if (res
!= -EAGAIN
&& res
!= req
->result
)
2855 req_set_fail_links(req
);
2857 WRITE_ONCE(req
->result
, res
);
2858 /* order with io_poll_complete() checking ->result */
2860 WRITE_ONCE(req
->iopoll_completed
, 1);
2864 * After the iocb has been issued, it's safe to be found on the poll list.
2865 * Adding the kiocb to the list AFTER submission ensures that we don't
2866 * find it from a io_iopoll_getevents() thread before the issuer is done
2867 * accessing the kiocb cookie.
2869 static void io_iopoll_req_issued(struct io_kiocb
*req
, bool in_async
)
2871 struct io_ring_ctx
*ctx
= req
->ctx
;
2874 * Track whether we have multiple files in our lists. This will impact
2875 * how we do polling eventually, not spinning if we're on potentially
2876 * different devices.
2878 if (list_empty(&ctx
->iopoll_list
)) {
2879 ctx
->poll_multi_file
= false;
2880 } else if (!ctx
->poll_multi_file
) {
2881 struct io_kiocb
*list_req
;
2883 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2885 if (list_req
->file
!= req
->file
)
2886 ctx
->poll_multi_file
= true;
2890 * For fast devices, IO may have already completed. If it has, add
2891 * it to the front so we find it first.
2893 if (READ_ONCE(req
->iopoll_completed
))
2894 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2896 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2899 * If IORING_SETUP_SQPOLL is enabled, sqes are either handled in sq thread
2900 * task context or in io worker task context. If current task context is
2901 * sq thread, we don't need to check whether should wake up sq thread.
2903 if (in_async
&& (ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2904 wq_has_sleeper(&ctx
->sq_data
->wait
))
2905 wake_up(&ctx
->sq_data
->wait
);
2908 static inline void io_state_file_put(struct io_submit_state
*state
)
2910 if (state
->file_refs
) {
2911 fput_many(state
->file
, state
->file_refs
);
2912 state
->file_refs
= 0;
2917 * Get as many references to a file as we have IOs left in this submission,
2918 * assuming most submissions are for one file, or at least that each file
2919 * has more than one submission.
2921 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2926 if (state
->file_refs
) {
2927 if (state
->fd
== fd
) {
2931 io_state_file_put(state
);
2933 state
->file
= fget_many(fd
, state
->ios_left
);
2934 if (unlikely(!state
->file
))
2938 state
->file_refs
= state
->ios_left
- 1;
2942 static bool io_bdev_nowait(struct block_device
*bdev
)
2944 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2948 * If we tracked the file through the SCM inflight mechanism, we could support
2949 * any file. For now, just ensure that anything potentially problematic is done
2952 static bool io_file_supports_async(struct file
*file
, int rw
)
2954 umode_t mode
= file_inode(file
)->i_mode
;
2956 if (S_ISBLK(mode
)) {
2957 if (IS_ENABLED(CONFIG_BLOCK
) &&
2958 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2962 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2964 if (S_ISREG(mode
)) {
2965 if (IS_ENABLED(CONFIG_BLOCK
) &&
2966 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2967 file
->f_op
!= &io_uring_fops
)
2972 /* any ->read/write should understand O_NONBLOCK */
2973 if (file
->f_flags
& O_NONBLOCK
)
2976 if (!(file
->f_mode
& FMODE_NOWAIT
))
2980 return file
->f_op
->read_iter
!= NULL
;
2982 return file
->f_op
->write_iter
!= NULL
;
2985 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2987 struct io_ring_ctx
*ctx
= req
->ctx
;
2988 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2989 struct file
*file
= req
->file
;
2993 if (S_ISREG(file_inode(file
)->i_mode
))
2994 req
->flags
|= REQ_F_ISREG
;
2996 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2997 if (kiocb
->ki_pos
== -1 && !(file
->f_mode
& FMODE_STREAM
)) {
2998 req
->flags
|= REQ_F_CUR_POS
;
2999 kiocb
->ki_pos
= file
->f_pos
;
3001 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
3002 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
3003 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
3007 /* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
3008 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) || (file
->f_flags
& O_NONBLOCK
))
3009 req
->flags
|= REQ_F_NOWAIT
;
3011 ioprio
= READ_ONCE(sqe
->ioprio
);
3013 ret
= ioprio_check_cap(ioprio
);
3017 kiocb
->ki_ioprio
= ioprio
;
3019 kiocb
->ki_ioprio
= get_current_ioprio();
3021 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
3022 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
3023 !kiocb
->ki_filp
->f_op
->iopoll
)
3026 kiocb
->ki_flags
|= IOCB_HIPRI
;
3027 kiocb
->ki_complete
= io_complete_rw_iopoll
;
3028 req
->iopoll_completed
= 0;
3030 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3032 kiocb
->ki_complete
= io_complete_rw
;
3035 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
3036 req
->rw
.len
= READ_ONCE(sqe
->len
);
3037 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
3041 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
3047 case -ERESTARTNOINTR
:
3048 case -ERESTARTNOHAND
:
3049 case -ERESTART_RESTARTBLOCK
:
3051 * We can't just restart the syscall, since previously
3052 * submitted sqes may already be in progress. Just fail this
3058 kiocb
->ki_complete(kiocb
, ret
, 0);
3062 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
3063 unsigned int issue_flags
)
3065 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
3066 struct io_async_rw
*io
= req
->async_data
;
3068 /* add previously done IO, if any */
3069 if (io
&& io
->bytes_done
> 0) {
3071 ret
= io
->bytes_done
;
3073 ret
+= io
->bytes_done
;
3076 if (req
->flags
& REQ_F_CUR_POS
)
3077 req
->file
->f_pos
= kiocb
->ki_pos
;
3078 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
3079 __io_complete_rw(req
, ret
, 0, issue_flags
);
3081 io_rw_done(kiocb
, ret
);
3084 static int io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
)
3086 struct io_ring_ctx
*ctx
= req
->ctx
;
3087 size_t len
= req
->rw
.len
;
3088 struct io_mapped_ubuf
*imu
;
3089 u16 index
, buf_index
= req
->buf_index
;
3093 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
3095 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
3096 imu
= &ctx
->user_bufs
[index
];
3097 buf_addr
= req
->rw
.addr
;
3100 if (buf_addr
+ len
< buf_addr
)
3102 /* not inside the mapped region */
3103 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
3107 * May not be a start of buffer, set size appropriately
3108 * and advance us to the beginning.
3110 offset
= buf_addr
- imu
->ubuf
;
3111 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
3115 * Don't use iov_iter_advance() here, as it's really slow for
3116 * using the latter parts of a big fixed buffer - it iterates
3117 * over each segment manually. We can cheat a bit here, because
3120 * 1) it's a BVEC iter, we set it up
3121 * 2) all bvecs are PAGE_SIZE in size, except potentially the
3122 * first and last bvec
3124 * So just find our index, and adjust the iterator afterwards.
3125 * If the offset is within the first bvec (or the whole first
3126 * bvec, just use iov_iter_advance(). This makes it easier
3127 * since we can just skip the first segment, which may not
3128 * be PAGE_SIZE aligned.
3130 const struct bio_vec
*bvec
= imu
->bvec
;
3132 if (offset
<= bvec
->bv_len
) {
3133 iov_iter_advance(iter
, offset
);
3135 unsigned long seg_skip
;
3137 /* skip first vec */
3138 offset
-= bvec
->bv_len
;
3139 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
3141 iter
->bvec
= bvec
+ seg_skip
;
3142 iter
->nr_segs
-= seg_skip
;
3143 iter
->count
-= bvec
->bv_len
+ offset
;
3144 iter
->iov_offset
= offset
& ~PAGE_MASK
;
3151 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3154 mutex_unlock(&ctx
->uring_lock
);
3157 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3160 * "Normal" inline submissions always hold the uring_lock, since we
3161 * grab it from the system call. Same is true for the SQPOLL offload.
3162 * The only exception is when we've detached the request and issue it
3163 * from an async worker thread, grab the lock for that case.
3166 mutex_lock(&ctx
->uring_lock
);
3169 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
3170 int bgid
, struct io_buffer
*kbuf
,
3173 struct io_buffer
*head
;
3175 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
3178 io_ring_submit_lock(req
->ctx
, needs_lock
);
3180 lockdep_assert_held(&req
->ctx
->uring_lock
);
3182 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
3184 if (!list_empty(&head
->list
)) {
3185 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
3187 list_del(&kbuf
->list
);
3190 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
3192 if (*len
> kbuf
->len
)
3195 kbuf
= ERR_PTR(-ENOBUFS
);
3198 io_ring_submit_unlock(req
->ctx
, needs_lock
);
3203 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
3206 struct io_buffer
*kbuf
;
3209 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3210 bgid
= req
->buf_index
;
3211 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
3214 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
3215 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3216 return u64_to_user_ptr(kbuf
->addr
);
3219 #ifdef CONFIG_COMPAT
3220 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
3223 struct compat_iovec __user
*uiov
;
3224 compat_ssize_t clen
;
3228 uiov
= u64_to_user_ptr(req
->rw
.addr
);
3229 if (!access_ok(uiov
, sizeof(*uiov
)))
3231 if (__get_user(clen
, &uiov
->iov_len
))
3237 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3239 return PTR_ERR(buf
);
3240 iov
[0].iov_base
= buf
;
3241 iov
[0].iov_len
= (compat_size_t
) len
;
3246 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3249 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
3253 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3256 len
= iov
[0].iov_len
;
3259 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3261 return PTR_ERR(buf
);
3262 iov
[0].iov_base
= buf
;
3263 iov
[0].iov_len
= len
;
3267 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3270 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3271 struct io_buffer
*kbuf
;
3273 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3274 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3275 iov
[0].iov_len
= kbuf
->len
;
3278 if (req
->rw
.len
!= 1)
3281 #ifdef CONFIG_COMPAT
3282 if (req
->ctx
->compat
)
3283 return io_compat_import(req
, iov
, needs_lock
);
3286 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3289 static int io_import_iovec(int rw
, struct io_kiocb
*req
, struct iovec
**iovec
,
3290 struct iov_iter
*iter
, bool needs_lock
)
3292 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3293 size_t sqe_len
= req
->rw
.len
;
3294 u8 opcode
= req
->opcode
;
3297 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3299 return io_import_fixed(req
, rw
, iter
);
3302 /* buffer index only valid with fixed read/write, or buffer select */
3303 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3306 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3307 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3308 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3310 return PTR_ERR(buf
);
3311 req
->rw
.len
= sqe_len
;
3314 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3319 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3320 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3322 iov_iter_init(iter
, rw
, *iovec
, 1, (*iovec
)->iov_len
);
3327 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3331 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3333 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3337 * For files that don't have ->read_iter() and ->write_iter(), handle them
3338 * by looping over ->read() or ->write() manually.
3340 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3342 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3343 struct file
*file
= req
->file
;
3347 * Don't support polled IO through this interface, and we can't
3348 * support non-blocking either. For the latter, this just causes
3349 * the kiocb to be handled from an async context.
3351 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3353 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3356 while (iov_iter_count(iter
)) {
3360 if (!iov_iter_is_bvec(iter
)) {
3361 iovec
= iov_iter_iovec(iter
);
3363 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3364 iovec
.iov_len
= req
->rw
.len
;
3368 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3369 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3371 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3372 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3381 if (nr
!= iovec
.iov_len
)
3385 iov_iter_advance(iter
, nr
);
3391 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3392 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3394 struct io_async_rw
*rw
= req
->async_data
;
3396 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3397 rw
->free_iovec
= iovec
;
3399 /* can only be fixed buffers, no need to do anything */
3400 if (iov_iter_is_bvec(iter
))
3403 unsigned iov_off
= 0;
3405 rw
->iter
.iov
= rw
->fast_iov
;
3406 if (iter
->iov
!= fast_iov
) {
3407 iov_off
= iter
->iov
- fast_iov
;
3408 rw
->iter
.iov
+= iov_off
;
3410 if (rw
->fast_iov
!= fast_iov
)
3411 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3412 sizeof(struct iovec
) * iter
->nr_segs
);
3414 req
->flags
|= REQ_F_NEED_CLEANUP
;
3418 static inline int __io_alloc_async_data(struct io_kiocb
*req
)
3420 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3421 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3422 return req
->async_data
== NULL
;
3425 static int io_alloc_async_data(struct io_kiocb
*req
)
3427 if (!io_op_defs
[req
->opcode
].needs_async_data
)
3430 return __io_alloc_async_data(req
);
3433 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3434 const struct iovec
*fast_iov
,
3435 struct iov_iter
*iter
, bool force
)
3437 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_data
)
3439 if (!req
->async_data
) {
3440 if (__io_alloc_async_data(req
)) {
3445 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3450 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3452 struct io_async_rw
*iorw
= req
->async_data
;
3453 struct iovec
*iov
= iorw
->fast_iov
;
3456 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3457 if (unlikely(ret
< 0))
3460 iorw
->bytes_done
= 0;
3461 iorw
->free_iovec
= iov
;
3463 req
->flags
|= REQ_F_NEED_CLEANUP
;
3467 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3471 ret
= io_prep_rw(req
, sqe
);
3475 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3478 /* either don't need iovec imported or already have it */
3479 if (!req
->async_data
)
3481 return io_rw_prep_async(req
, READ
);
3485 * This is our waitqueue callback handler, registered through lock_page_async()
3486 * when we initially tried to do the IO with the iocb armed our waitqueue.
3487 * This gets called when the page is unlocked, and we generally expect that to
3488 * happen when the page IO is completed and the page is now uptodate. This will
3489 * queue a task_work based retry of the operation, attempting to copy the data
3490 * again. If the latter fails because the page was NOT uptodate, then we will
3491 * do a thread based blocking retry of the operation. That's the unexpected
3494 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3495 int sync
, void *arg
)
3497 struct wait_page_queue
*wpq
;
3498 struct io_kiocb
*req
= wait
->private;
3499 struct wait_page_key
*key
= arg
;
3501 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3503 if (!wake_page_match(wpq
, key
))
3506 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3507 list_del_init(&wait
->entry
);
3509 /* submit ref gets dropped, acquire a new one */
3510 refcount_inc(&req
->refs
);
3511 io_req_task_queue(req
);
3516 * This controls whether a given IO request should be armed for async page
3517 * based retry. If we return false here, the request is handed to the async
3518 * worker threads for retry. If we're doing buffered reads on a regular file,
3519 * we prepare a private wait_page_queue entry and retry the operation. This
3520 * will either succeed because the page is now uptodate and unlocked, or it
3521 * will register a callback when the page is unlocked at IO completion. Through
3522 * that callback, io_uring uses task_work to setup a retry of the operation.
3523 * That retry will attempt the buffered read again. The retry will generally
3524 * succeed, or in rare cases where it fails, we then fall back to using the
3525 * async worker threads for a blocking retry.
3527 static bool io_rw_should_retry(struct io_kiocb
*req
)
3529 struct io_async_rw
*rw
= req
->async_data
;
3530 struct wait_page_queue
*wait
= &rw
->wpq
;
3531 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3533 /* never retry for NOWAIT, we just complete with -EAGAIN */
3534 if (req
->flags
& REQ_F_NOWAIT
)
3537 /* Only for buffered IO */
3538 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3542 * just use poll if we can, and don't attempt if the fs doesn't
3543 * support callback based unlocks
3545 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3548 wait
->wait
.func
= io_async_buf_func
;
3549 wait
->wait
.private = req
;
3550 wait
->wait
.flags
= 0;
3551 INIT_LIST_HEAD(&wait
->wait
.entry
);
3552 kiocb
->ki_flags
|= IOCB_WAITQ
;
3553 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3554 kiocb
->ki_waitq
= wait
;
3558 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3560 if (req
->file
->f_op
->read_iter
)
3561 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3562 else if (req
->file
->f_op
->read
)
3563 return loop_rw_iter(READ
, req
, iter
);
3568 static int io_read(struct io_kiocb
*req
, unsigned int issue_flags
)
3570 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3571 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3572 struct iov_iter __iter
, *iter
= &__iter
;
3573 struct io_async_rw
*rw
= req
->async_data
;
3574 ssize_t io_size
, ret
, ret2
;
3575 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3581 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3585 io_size
= iov_iter_count(iter
);
3586 req
->result
= io_size
;
3588 /* Ensure we clear previously set non-block flag */
3589 if (!force_nonblock
)
3590 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3592 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3594 /* If the file doesn't support async, just async punt */
3595 if (force_nonblock
&& !io_file_supports_async(req
->file
, READ
)) {
3596 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3597 return ret
?: -EAGAIN
;
3600 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3601 if (unlikely(ret
)) {
3606 ret
= io_iter_do_read(req
, iter
);
3608 if (ret
== -EIOCBQUEUED
) {
3610 } else if (ret
== -EAGAIN
) {
3611 /* IOPOLL retry should happen for io-wq threads */
3612 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3614 /* no retry on NONBLOCK nor RWF_NOWAIT */
3615 if (req
->flags
& REQ_F_NOWAIT
)
3617 /* some cases will consume bytes even on error returns */
3618 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3620 } else if (ret
<= 0 || ret
== io_size
|| !force_nonblock
||
3621 (req
->flags
& REQ_F_NOWAIT
) || !(req
->flags
& REQ_F_ISREG
)) {
3622 /* read all, failed, already did sync or don't want to retry */
3626 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3631 rw
= req
->async_data
;
3632 /* now use our persistent iterator, if we aren't already */
3637 rw
->bytes_done
+= ret
;
3638 /* if we can retry, do so with the callbacks armed */
3639 if (!io_rw_should_retry(req
)) {
3640 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3645 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3646 * we get -EIOCBQUEUED, then we'll get a notification when the
3647 * desired page gets unlocked. We can also get a partial read
3648 * here, and if we do, then just retry at the new offset.
3650 ret
= io_iter_do_read(req
, iter
);
3651 if (ret
== -EIOCBQUEUED
)
3653 /* we got some bytes, but not all. retry. */
3654 } while (ret
> 0 && ret
< io_size
);
3656 kiocb_done(kiocb
, ret
, issue_flags
);
3658 /* it's faster to check here then delegate to kfree */
3664 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3668 ret
= io_prep_rw(req
, sqe
);
3672 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3675 /* either don't need iovec imported or already have it */
3676 if (!req
->async_data
)
3678 return io_rw_prep_async(req
, WRITE
);
3681 static int io_write(struct io_kiocb
*req
, unsigned int issue_flags
)
3683 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3684 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3685 struct iov_iter __iter
, *iter
= &__iter
;
3686 struct io_async_rw
*rw
= req
->async_data
;
3687 ssize_t ret
, ret2
, io_size
;
3688 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3694 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3698 io_size
= iov_iter_count(iter
);
3699 req
->result
= io_size
;
3701 /* Ensure we clear previously set non-block flag */
3702 if (!force_nonblock
)
3703 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3705 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3707 /* If the file doesn't support async, just async punt */
3708 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3711 /* file path doesn't support NOWAIT for non-direct_IO */
3712 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3713 (req
->flags
& REQ_F_ISREG
))
3716 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3721 * Open-code file_start_write here to grab freeze protection,
3722 * which will be released by another thread in
3723 * io_complete_rw(). Fool lockdep by telling it the lock got
3724 * released so that it doesn't complain about the held lock when
3725 * we return to userspace.
3727 if (req
->flags
& REQ_F_ISREG
) {
3728 sb_start_write(file_inode(req
->file
)->i_sb
);
3729 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3732 kiocb
->ki_flags
|= IOCB_WRITE
;
3734 if (req
->file
->f_op
->write_iter
)
3735 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3736 else if (req
->file
->f_op
->write
)
3737 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3742 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3743 * retry them without IOCB_NOWAIT.
3745 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3747 /* no retry on NONBLOCK nor RWF_NOWAIT */
3748 if (ret2
== -EAGAIN
&& (req
->flags
& REQ_F_NOWAIT
))
3750 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3751 /* IOPOLL retry should happen for io-wq threads */
3752 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3755 kiocb_done(kiocb
, ret2
, issue_flags
);
3758 /* some cases will consume bytes even on error returns */
3759 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3760 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3761 return ret
?: -EAGAIN
;
3764 /* it's reportedly faster than delegating the null check to kfree() */
3770 static int io_renameat_prep(struct io_kiocb
*req
,
3771 const struct io_uring_sqe
*sqe
)
3773 struct io_rename
*ren
= &req
->rename
;
3774 const char __user
*oldf
, *newf
;
3776 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3779 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3780 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3781 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3782 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3783 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3785 ren
->oldpath
= getname(oldf
);
3786 if (IS_ERR(ren
->oldpath
))
3787 return PTR_ERR(ren
->oldpath
);
3789 ren
->newpath
= getname(newf
);
3790 if (IS_ERR(ren
->newpath
)) {
3791 putname(ren
->oldpath
);
3792 return PTR_ERR(ren
->newpath
);
3795 req
->flags
|= REQ_F_NEED_CLEANUP
;
3799 static int io_renameat(struct io_kiocb
*req
, unsigned int issue_flags
)
3801 struct io_rename
*ren
= &req
->rename
;
3804 if (issue_flags
& IO_URING_F_NONBLOCK
)
3807 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3808 ren
->newpath
, ren
->flags
);
3810 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3812 req_set_fail_links(req
);
3813 io_req_complete(req
, ret
);
3817 static int io_unlinkat_prep(struct io_kiocb
*req
,
3818 const struct io_uring_sqe
*sqe
)
3820 struct io_unlink
*un
= &req
->unlink
;
3821 const char __user
*fname
;
3823 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3826 un
->dfd
= READ_ONCE(sqe
->fd
);
3828 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3829 if (un
->flags
& ~AT_REMOVEDIR
)
3832 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3833 un
->filename
= getname(fname
);
3834 if (IS_ERR(un
->filename
))
3835 return PTR_ERR(un
->filename
);
3837 req
->flags
|= REQ_F_NEED_CLEANUP
;
3841 static int io_unlinkat(struct io_kiocb
*req
, unsigned int issue_flags
)
3843 struct io_unlink
*un
= &req
->unlink
;
3846 if (issue_flags
& IO_URING_F_NONBLOCK
)
3849 if (un
->flags
& AT_REMOVEDIR
)
3850 ret
= do_rmdir(un
->dfd
, un
->filename
);
3852 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3854 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3856 req_set_fail_links(req
);
3857 io_req_complete(req
, ret
);
3861 static int io_shutdown_prep(struct io_kiocb
*req
,
3862 const struct io_uring_sqe
*sqe
)
3864 #if defined(CONFIG_NET)
3865 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3867 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3871 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3878 static int io_shutdown(struct io_kiocb
*req
, unsigned int issue_flags
)
3880 #if defined(CONFIG_NET)
3881 struct socket
*sock
;
3884 if (issue_flags
& IO_URING_F_NONBLOCK
)
3887 sock
= sock_from_file(req
->file
);
3888 if (unlikely(!sock
))
3891 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3893 req_set_fail_links(req
);
3894 io_req_complete(req
, ret
);
3901 static int __io_splice_prep(struct io_kiocb
*req
,
3902 const struct io_uring_sqe
*sqe
)
3904 struct io_splice
* sp
= &req
->splice
;
3905 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3907 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3911 sp
->len
= READ_ONCE(sqe
->len
);
3912 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3914 if (unlikely(sp
->flags
& ~valid_flags
))
3917 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3918 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3921 req
->flags
|= REQ_F_NEED_CLEANUP
;
3923 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3925 * Splice operation will be punted aync, and here need to
3926 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3928 io_req_init_async(req
);
3929 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3935 static int io_tee_prep(struct io_kiocb
*req
,
3936 const struct io_uring_sqe
*sqe
)
3938 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3940 return __io_splice_prep(req
, sqe
);
3943 static int io_tee(struct io_kiocb
*req
, unsigned int issue_flags
)
3945 struct io_splice
*sp
= &req
->splice
;
3946 struct file
*in
= sp
->file_in
;
3947 struct file
*out
= sp
->file_out
;
3948 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3951 if (issue_flags
& IO_URING_F_NONBLOCK
)
3954 ret
= do_tee(in
, out
, sp
->len
, flags
);
3956 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3957 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3960 req_set_fail_links(req
);
3961 io_req_complete(req
, ret
);
3965 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3967 struct io_splice
* sp
= &req
->splice
;
3969 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3970 sp
->off_out
= READ_ONCE(sqe
->off
);
3971 return __io_splice_prep(req
, sqe
);
3974 static int io_splice(struct io_kiocb
*req
, unsigned int issue_flags
)
3976 struct io_splice
*sp
= &req
->splice
;
3977 struct file
*in
= sp
->file_in
;
3978 struct file
*out
= sp
->file_out
;
3979 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3980 loff_t
*poff_in
, *poff_out
;
3983 if (issue_flags
& IO_URING_F_NONBLOCK
)
3986 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3987 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3990 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3992 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3993 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3996 req_set_fail_links(req
);
3997 io_req_complete(req
, ret
);
4002 * IORING_OP_NOP just posts a completion event, nothing else.
4004 static int io_nop(struct io_kiocb
*req
, unsigned int issue_flags
)
4006 struct io_ring_ctx
*ctx
= req
->ctx
;
4008 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4011 __io_req_complete(req
, issue_flags
, 0, 0);
4015 static int io_fsync_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4017 struct io_ring_ctx
*ctx
= req
->ctx
;
4022 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4024 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4027 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
4028 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
4031 req
->sync
.off
= READ_ONCE(sqe
->off
);
4032 req
->sync
.len
= READ_ONCE(sqe
->len
);
4036 static int io_fsync(struct io_kiocb
*req
, unsigned int issue_flags
)
4038 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
4041 /* fsync always requires a blocking context */
4042 if (issue_flags
& IO_URING_F_NONBLOCK
)
4045 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
4046 end
> 0 ? end
: LLONG_MAX
,
4047 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
4049 req_set_fail_links(req
);
4050 io_req_complete(req
, ret
);
4054 static int io_fallocate_prep(struct io_kiocb
*req
,
4055 const struct io_uring_sqe
*sqe
)
4057 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
4059 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4062 req
->sync
.off
= READ_ONCE(sqe
->off
);
4063 req
->sync
.len
= READ_ONCE(sqe
->addr
);
4064 req
->sync
.mode
= READ_ONCE(sqe
->len
);
4068 static int io_fallocate(struct io_kiocb
*req
, unsigned int issue_flags
)
4072 /* fallocate always requiring blocking context */
4073 if (issue_flags
& IO_URING_F_NONBLOCK
)
4075 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
4078 req_set_fail_links(req
);
4079 io_req_complete(req
, ret
);
4083 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4085 const char __user
*fname
;
4088 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
4090 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
4093 /* open.how should be already initialised */
4094 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
4095 req
->open
.how
.flags
|= O_LARGEFILE
;
4097 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
4098 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4099 req
->open
.filename
= getname(fname
);
4100 if (IS_ERR(req
->open
.filename
)) {
4101 ret
= PTR_ERR(req
->open
.filename
);
4102 req
->open
.filename
= NULL
;
4105 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
4106 req
->flags
|= REQ_F_NEED_CLEANUP
;
4110 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4114 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4116 mode
= READ_ONCE(sqe
->len
);
4117 flags
= READ_ONCE(sqe
->open_flags
);
4118 req
->open
.how
= build_open_how(flags
, mode
);
4119 return __io_openat_prep(req
, sqe
);
4122 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4124 struct open_how __user
*how
;
4128 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4130 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4131 len
= READ_ONCE(sqe
->len
);
4132 if (len
< OPEN_HOW_SIZE_VER0
)
4135 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
4140 return __io_openat_prep(req
, sqe
);
4143 static int io_openat2(struct io_kiocb
*req
, unsigned int issue_flags
)
4145 struct open_flags op
;
4148 bool resolve_nonblock
;
4151 ret
= build_open_flags(&req
->open
.how
, &op
);
4154 nonblock_set
= op
.open_flag
& O_NONBLOCK
;
4155 resolve_nonblock
= req
->open
.how
.resolve
& RESOLVE_CACHED
;
4156 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4158 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
4159 * it'll always -EAGAIN
4161 if (req
->open
.how
.flags
& (O_TRUNC
| O_CREAT
| O_TMPFILE
))
4163 op
.lookup_flags
|= LOOKUP_CACHED
;
4164 op
.open_flag
|= O_NONBLOCK
;
4167 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
4171 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
4172 /* only retry if RESOLVE_CACHED wasn't already set by application */
4173 if ((!resolve_nonblock
&& (issue_flags
& IO_URING_F_NONBLOCK
)) &&
4174 file
== ERR_PTR(-EAGAIN
)) {
4176 * We could hang on to this 'fd', but seems like marginal
4177 * gain for something that is now known to be a slower path.
4178 * So just put it, and we'll get a new one when we retry.
4186 ret
= PTR_ERR(file
);
4188 if ((issue_flags
& IO_URING_F_NONBLOCK
) && !nonblock_set
)
4189 file
->f_flags
&= ~O_NONBLOCK
;
4190 fsnotify_open(file
);
4191 fd_install(ret
, file
);
4194 putname(req
->open
.filename
);
4195 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4197 req_set_fail_links(req
);
4198 io_req_complete(req
, ret
);
4202 static int io_openat(struct io_kiocb
*req
, unsigned int issue_flags
)
4204 return io_openat2(req
, issue_flags
& IO_URING_F_NONBLOCK
);
4207 static int io_remove_buffers_prep(struct io_kiocb
*req
,
4208 const struct io_uring_sqe
*sqe
)
4210 struct io_provide_buf
*p
= &req
->pbuf
;
4213 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
4216 tmp
= READ_ONCE(sqe
->fd
);
4217 if (!tmp
|| tmp
> USHRT_MAX
)
4220 memset(p
, 0, sizeof(*p
));
4222 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4226 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
4227 int bgid
, unsigned nbufs
)
4231 /* shouldn't happen */
4235 /* the head kbuf is the list itself */
4236 while (!list_empty(&buf
->list
)) {
4237 struct io_buffer
*nxt
;
4239 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
4240 list_del(&nxt
->list
);
4247 idr_remove(&ctx
->io_buffer_idr
, bgid
);
4252 static int io_remove_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
4254 struct io_provide_buf
*p
= &req
->pbuf
;
4255 struct io_ring_ctx
*ctx
= req
->ctx
;
4256 struct io_buffer
*head
;
4258 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4260 io_ring_submit_lock(ctx
, !force_nonblock
);
4262 lockdep_assert_held(&ctx
->uring_lock
);
4265 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
4267 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
4269 req_set_fail_links(req
);
4271 /* need to hold the lock to complete IOPOLL requests */
4272 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
4273 __io_req_complete(req
, issue_flags
, ret
, 0);
4274 io_ring_submit_unlock(ctx
, !force_nonblock
);
4276 io_ring_submit_unlock(ctx
, !force_nonblock
);
4277 __io_req_complete(req
, issue_flags
, ret
, 0);
4282 static int io_provide_buffers_prep(struct io_kiocb
*req
,
4283 const struct io_uring_sqe
*sqe
)
4285 struct io_provide_buf
*p
= &req
->pbuf
;
4288 if (sqe
->ioprio
|| sqe
->rw_flags
)
4291 tmp
= READ_ONCE(sqe
->fd
);
4292 if (!tmp
|| tmp
> USHRT_MAX
)
4295 p
->addr
= READ_ONCE(sqe
->addr
);
4296 p
->len
= READ_ONCE(sqe
->len
);
4298 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
4301 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4302 tmp
= READ_ONCE(sqe
->off
);
4303 if (tmp
> USHRT_MAX
)
4309 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
4311 struct io_buffer
*buf
;
4312 u64 addr
= pbuf
->addr
;
4313 int i
, bid
= pbuf
->bid
;
4315 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
4316 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
4321 buf
->len
= pbuf
->len
;
4326 INIT_LIST_HEAD(&buf
->list
);
4329 list_add_tail(&buf
->list
, &(*head
)->list
);
4333 return i
? i
: -ENOMEM
;
4336 static int io_provide_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
4338 struct io_provide_buf
*p
= &req
->pbuf
;
4339 struct io_ring_ctx
*ctx
= req
->ctx
;
4340 struct io_buffer
*head
, *list
;
4342 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4344 io_ring_submit_lock(ctx
, !force_nonblock
);
4346 lockdep_assert_held(&ctx
->uring_lock
);
4348 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
4350 ret
= io_add_buffers(p
, &head
);
4355 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
4358 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4364 req_set_fail_links(req
);
4366 /* need to hold the lock to complete IOPOLL requests */
4367 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
4368 __io_req_complete(req
, issue_flags
, ret
, 0);
4369 io_ring_submit_unlock(ctx
, !force_nonblock
);
4371 io_ring_submit_unlock(ctx
, !force_nonblock
);
4372 __io_req_complete(req
, issue_flags
, ret
, 0);
4377 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4378 const struct io_uring_sqe
*sqe
)
4380 #if defined(CONFIG_EPOLL)
4381 if (sqe
->ioprio
|| sqe
->buf_index
)
4383 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4386 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4387 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4388 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4390 if (ep_op_has_event(req
->epoll
.op
)) {
4391 struct epoll_event __user
*ev
;
4393 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4394 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4404 static int io_epoll_ctl(struct io_kiocb
*req
, unsigned int issue_flags
)
4406 #if defined(CONFIG_EPOLL)
4407 struct io_epoll
*ie
= &req
->epoll
;
4409 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4411 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4412 if (force_nonblock
&& ret
== -EAGAIN
)
4416 req_set_fail_links(req
);
4417 __io_req_complete(req
, issue_flags
, ret
, 0);
4424 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4426 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4427 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4429 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4432 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4433 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4434 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4441 static int io_madvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4443 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4444 struct io_madvise
*ma
= &req
->madvise
;
4447 if (issue_flags
& IO_URING_F_NONBLOCK
)
4450 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4452 req_set_fail_links(req
);
4453 io_req_complete(req
, ret
);
4460 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4462 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4464 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4467 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4468 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4469 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4473 static int io_fadvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4475 struct io_fadvise
*fa
= &req
->fadvise
;
4478 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4479 switch (fa
->advice
) {
4480 case POSIX_FADV_NORMAL
:
4481 case POSIX_FADV_RANDOM
:
4482 case POSIX_FADV_SEQUENTIAL
:
4489 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4491 req_set_fail_links(req
);
4492 io_req_complete(req
, ret
);
4496 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4498 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4500 if (sqe
->ioprio
|| sqe
->buf_index
)
4502 if (req
->flags
& REQ_F_FIXED_FILE
)
4505 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4506 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4507 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4508 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4509 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4514 static int io_statx(struct io_kiocb
*req
, unsigned int issue_flags
)
4516 struct io_statx
*ctx
= &req
->statx
;
4519 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4520 /* only need file table for an actual valid fd */
4521 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
4522 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4526 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4530 req_set_fail_links(req
);
4531 io_req_complete(req
, ret
);
4535 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4537 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4539 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4540 sqe
->rw_flags
|| sqe
->buf_index
)
4542 if (req
->flags
& REQ_F_FIXED_FILE
)
4545 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4549 static int io_close(struct io_kiocb
*req
, unsigned int issue_flags
)
4551 struct files_struct
*files
= current
->files
;
4552 struct io_close
*close
= &req
->close
;
4553 struct fdtable
*fdt
;
4559 spin_lock(&files
->file_lock
);
4560 fdt
= files_fdtable(files
);
4561 if (close
->fd
>= fdt
->max_fds
) {
4562 spin_unlock(&files
->file_lock
);
4565 file
= fdt
->fd
[close
->fd
];
4567 spin_unlock(&files
->file_lock
);
4571 if (file
->f_op
== &io_uring_fops
) {
4572 spin_unlock(&files
->file_lock
);
4577 /* if the file has a flush method, be safe and punt to async */
4578 if (file
->f_op
->flush
&& (issue_flags
& IO_URING_F_NONBLOCK
)) {
4579 spin_unlock(&files
->file_lock
);
4583 ret
= __close_fd_get_file(close
->fd
, &file
);
4584 spin_unlock(&files
->file_lock
);
4591 /* No ->flush() or already async, safely close from here */
4592 ret
= filp_close(file
, current
->files
);
4595 req_set_fail_links(req
);
4598 __io_req_complete(req
, issue_flags
, ret
, 0);
4602 static int io_sfr_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4604 struct io_ring_ctx
*ctx
= req
->ctx
;
4606 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4608 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4611 req
->sync
.off
= READ_ONCE(sqe
->off
);
4612 req
->sync
.len
= READ_ONCE(sqe
->len
);
4613 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4617 static int io_sync_file_range(struct io_kiocb
*req
, unsigned int issue_flags
)
4621 /* sync_file_range always requires a blocking context */
4622 if (issue_flags
& IO_URING_F_NONBLOCK
)
4625 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4628 req_set_fail_links(req
);
4629 io_req_complete(req
, ret
);
4633 #if defined(CONFIG_NET)
4634 static int io_setup_async_msg(struct io_kiocb
*req
,
4635 struct io_async_msghdr
*kmsg
)
4637 struct io_async_msghdr
*async_msg
= req
->async_data
;
4641 if (io_alloc_async_data(req
)) {
4642 kfree(kmsg
->free_iov
);
4645 async_msg
= req
->async_data
;
4646 req
->flags
|= REQ_F_NEED_CLEANUP
;
4647 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4648 async_msg
->msg
.msg_name
= &async_msg
->addr
;
4649 /* if were using fast_iov, set it to the new one */
4650 if (!async_msg
->free_iov
)
4651 async_msg
->msg
.msg_iter
.iov
= async_msg
->fast_iov
;
4656 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4657 struct io_async_msghdr
*iomsg
)
4659 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4660 iomsg
->free_iov
= iomsg
->fast_iov
;
4661 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4662 req
->sr_msg
.msg_flags
, &iomsg
->free_iov
);
4665 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4667 struct io_async_msghdr
*async_msg
= req
->async_data
;
4668 struct io_sr_msg
*sr
= &req
->sr_msg
;
4671 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4674 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4675 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4676 sr
->len
= READ_ONCE(sqe
->len
);
4678 #ifdef CONFIG_COMPAT
4679 if (req
->ctx
->compat
)
4680 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4683 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4685 ret
= io_sendmsg_copy_hdr(req
, async_msg
);
4687 req
->flags
|= REQ_F_NEED_CLEANUP
;
4691 static int io_sendmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4693 struct io_async_msghdr iomsg
, *kmsg
;
4694 struct socket
*sock
;
4698 sock
= sock_from_file(req
->file
);
4699 if (unlikely(!sock
))
4702 kmsg
= req
->async_data
;
4704 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4710 flags
= req
->sr_msg
.msg_flags
;
4711 if (flags
& MSG_DONTWAIT
)
4712 req
->flags
|= REQ_F_NOWAIT
;
4713 else if (issue_flags
& IO_URING_F_NONBLOCK
)
4714 flags
|= MSG_DONTWAIT
;
4716 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4717 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4718 return io_setup_async_msg(req
, kmsg
);
4719 if (ret
== -ERESTARTSYS
)
4722 /* fast path, check for non-NULL to avoid function call */
4724 kfree(kmsg
->free_iov
);
4725 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4727 req_set_fail_links(req
);
4728 __io_req_complete(req
, issue_flags
, ret
, 0);
4732 static int io_send(struct io_kiocb
*req
, unsigned int issue_flags
)
4734 struct io_sr_msg
*sr
= &req
->sr_msg
;
4737 struct socket
*sock
;
4741 sock
= sock_from_file(req
->file
);
4742 if (unlikely(!sock
))
4745 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4749 msg
.msg_name
= NULL
;
4750 msg
.msg_control
= NULL
;
4751 msg
.msg_controllen
= 0;
4752 msg
.msg_namelen
= 0;
4754 flags
= req
->sr_msg
.msg_flags
;
4755 if (flags
& MSG_DONTWAIT
)
4756 req
->flags
|= REQ_F_NOWAIT
;
4757 else if (issue_flags
& IO_URING_F_NONBLOCK
)
4758 flags
|= MSG_DONTWAIT
;
4760 msg
.msg_flags
= flags
;
4761 ret
= sock_sendmsg(sock
, &msg
);
4762 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4764 if (ret
== -ERESTARTSYS
)
4768 req_set_fail_links(req
);
4769 __io_req_complete(req
, issue_flags
, ret
, 0);
4773 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4774 struct io_async_msghdr
*iomsg
)
4776 struct io_sr_msg
*sr
= &req
->sr_msg
;
4777 struct iovec __user
*uiov
;
4781 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4782 &iomsg
->uaddr
, &uiov
, &iov_len
);
4786 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4789 if (copy_from_user(iomsg
->fast_iov
, uiov
, sizeof(*uiov
)))
4791 sr
->len
= iomsg
->fast_iov
[0].iov_len
;
4792 iomsg
->free_iov
= NULL
;
4794 iomsg
->free_iov
= iomsg
->fast_iov
;
4795 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4796 &iomsg
->free_iov
, &iomsg
->msg
.msg_iter
,
4805 #ifdef CONFIG_COMPAT
4806 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4807 struct io_async_msghdr
*iomsg
)
4809 struct compat_msghdr __user
*msg_compat
;
4810 struct io_sr_msg
*sr
= &req
->sr_msg
;
4811 struct compat_iovec __user
*uiov
;
4816 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4817 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4822 uiov
= compat_ptr(ptr
);
4823 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4824 compat_ssize_t clen
;
4828 if (!access_ok(uiov
, sizeof(*uiov
)))
4830 if (__get_user(clen
, &uiov
->iov_len
))
4835 iomsg
->free_iov
= NULL
;
4837 iomsg
->free_iov
= iomsg
->fast_iov
;
4838 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4839 UIO_FASTIOV
, &iomsg
->free_iov
,
4840 &iomsg
->msg
.msg_iter
, true);
4849 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4850 struct io_async_msghdr
*iomsg
)
4852 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4854 #ifdef CONFIG_COMPAT
4855 if (req
->ctx
->compat
)
4856 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4859 return __io_recvmsg_copy_hdr(req
, iomsg
);
4862 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4865 struct io_sr_msg
*sr
= &req
->sr_msg
;
4866 struct io_buffer
*kbuf
;
4868 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4873 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4877 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4879 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4882 static int io_recvmsg_prep(struct io_kiocb
*req
,
4883 const struct io_uring_sqe
*sqe
)
4885 struct io_async_msghdr
*async_msg
= req
->async_data
;
4886 struct io_sr_msg
*sr
= &req
->sr_msg
;
4889 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4892 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4893 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4894 sr
->len
= READ_ONCE(sqe
->len
);
4895 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4897 #ifdef CONFIG_COMPAT
4898 if (req
->ctx
->compat
)
4899 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4902 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4904 ret
= io_recvmsg_copy_hdr(req
, async_msg
);
4906 req
->flags
|= REQ_F_NEED_CLEANUP
;
4910 static int io_recvmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4912 struct io_async_msghdr iomsg
, *kmsg
;
4913 struct socket
*sock
;
4914 struct io_buffer
*kbuf
;
4916 int ret
, cflags
= 0;
4917 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4919 sock
= sock_from_file(req
->file
);
4920 if (unlikely(!sock
))
4923 kmsg
= req
->async_data
;
4925 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4931 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4932 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4934 return PTR_ERR(kbuf
);
4935 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4936 kmsg
->fast_iov
[0].iov_len
= req
->sr_msg
.len
;
4937 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->fast_iov
,
4938 1, req
->sr_msg
.len
);
4941 flags
= req
->sr_msg
.msg_flags
;
4942 if (flags
& MSG_DONTWAIT
)
4943 req
->flags
|= REQ_F_NOWAIT
;
4944 else if (force_nonblock
)
4945 flags
|= MSG_DONTWAIT
;
4947 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4948 kmsg
->uaddr
, flags
);
4949 if (force_nonblock
&& ret
== -EAGAIN
)
4950 return io_setup_async_msg(req
, kmsg
);
4951 if (ret
== -ERESTARTSYS
)
4954 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4955 cflags
= io_put_recv_kbuf(req
);
4956 /* fast path, check for non-NULL to avoid function call */
4958 kfree(kmsg
->free_iov
);
4959 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4961 req_set_fail_links(req
);
4962 __io_req_complete(req
, issue_flags
, ret
, cflags
);
4966 static int io_recv(struct io_kiocb
*req
, unsigned int issue_flags
)
4968 struct io_buffer
*kbuf
;
4969 struct io_sr_msg
*sr
= &req
->sr_msg
;
4971 void __user
*buf
= sr
->buf
;
4972 struct socket
*sock
;
4975 int ret
, cflags
= 0;
4976 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4978 sock
= sock_from_file(req
->file
);
4979 if (unlikely(!sock
))
4982 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4983 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4985 return PTR_ERR(kbuf
);
4986 buf
= u64_to_user_ptr(kbuf
->addr
);
4989 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4993 msg
.msg_name
= NULL
;
4994 msg
.msg_control
= NULL
;
4995 msg
.msg_controllen
= 0;
4996 msg
.msg_namelen
= 0;
4997 msg
.msg_iocb
= NULL
;
5000 flags
= req
->sr_msg
.msg_flags
;
5001 if (flags
& MSG_DONTWAIT
)
5002 req
->flags
|= REQ_F_NOWAIT
;
5003 else if (force_nonblock
)
5004 flags
|= MSG_DONTWAIT
;
5006 ret
= sock_recvmsg(sock
, &msg
, flags
);
5007 if (force_nonblock
&& ret
== -EAGAIN
)
5009 if (ret
== -ERESTARTSYS
)
5012 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5013 cflags
= io_put_recv_kbuf(req
);
5015 req_set_fail_links(req
);
5016 __io_req_complete(req
, issue_flags
, ret
, cflags
);
5020 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5022 struct io_accept
*accept
= &req
->accept
;
5024 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5026 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
5029 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
5030 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
5031 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
5032 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
5036 static int io_accept(struct io_kiocb
*req
, unsigned int issue_flags
)
5038 struct io_accept
*accept
= &req
->accept
;
5039 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
5040 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
5043 if (req
->file
->f_flags
& O_NONBLOCK
)
5044 req
->flags
|= REQ_F_NOWAIT
;
5046 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
5047 accept
->addr_len
, accept
->flags
,
5049 if (ret
== -EAGAIN
&& force_nonblock
)
5052 if (ret
== -ERESTARTSYS
)
5054 req_set_fail_links(req
);
5056 __io_req_complete(req
, issue_flags
, ret
, 0);
5060 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5062 struct io_connect
*conn
= &req
->connect
;
5063 struct io_async_connect
*io
= req
->async_data
;
5065 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5067 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
5070 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
5071 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
5076 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
5080 static int io_connect(struct io_kiocb
*req
, unsigned int issue_flags
)
5082 struct io_async_connect __io
, *io
;
5083 unsigned file_flags
;
5085 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
5087 if (req
->async_data
) {
5088 io
= req
->async_data
;
5090 ret
= move_addr_to_kernel(req
->connect
.addr
,
5091 req
->connect
.addr_len
,
5098 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
5100 ret
= __sys_connect_file(req
->file
, &io
->address
,
5101 req
->connect
.addr_len
, file_flags
);
5102 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
5103 if (req
->async_data
)
5105 if (io_alloc_async_data(req
)) {
5109 io
= req
->async_data
;
5110 memcpy(req
->async_data
, &__io
, sizeof(__io
));
5113 if (ret
== -ERESTARTSYS
)
5117 req_set_fail_links(req
);
5118 __io_req_complete(req
, issue_flags
, ret
, 0);
5121 #else /* !CONFIG_NET */
5122 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5127 static int io_sendmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
5132 static int io_send(struct io_kiocb
*req
, unsigned int issue_flags
)
5137 static int io_recvmsg_prep(struct io_kiocb
*req
,
5138 const struct io_uring_sqe
*sqe
)
5143 static int io_recvmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
5148 static int io_recv(struct io_kiocb
*req
, unsigned int issue_flags
)
5153 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5158 static int io_accept(struct io_kiocb
*req
, unsigned int issue_flags
)
5163 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5168 static int io_connect(struct io_kiocb
*req
, unsigned int issue_flags
)
5172 #endif /* CONFIG_NET */
5174 struct io_poll_table
{
5175 struct poll_table_struct pt
;
5176 struct io_kiocb
*req
;
5180 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
5181 __poll_t mask
, task_work_func_t func
)
5185 /* for instances that support it check for an event match first: */
5186 if (mask
&& !(mask
& poll
->events
))
5189 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
5191 list_del_init(&poll
->wait
.entry
);
5194 req
->task_work
.func
= func
;
5195 percpu_ref_get(&req
->ctx
->refs
);
5198 * If this fails, then the task is exiting. When a task exits, the
5199 * work gets canceled, so just cancel this request as well instead
5200 * of executing it. We can't safely execute it anyway, as we may not
5201 * have the needed state needed for it anyway.
5203 ret
= io_req_task_work_add(req
);
5204 if (unlikely(ret
)) {
5205 WRITE_ONCE(poll
->canceled
, true);
5206 io_req_task_work_add_fallback(req
, func
);
5211 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
5212 __acquires(&req
->ctx
->completion_lock
)
5214 struct io_ring_ctx
*ctx
= req
->ctx
;
5216 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5217 struct poll_table_struct pt
= { ._key
= poll
->events
};
5219 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
5222 spin_lock_irq(&ctx
->completion_lock
);
5223 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5224 add_wait_queue(poll
->head
, &poll
->wait
);
5231 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
5233 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
5234 if (req
->opcode
== IORING_OP_POLL_ADD
)
5235 return req
->async_data
;
5236 return req
->apoll
->double_poll
;
5239 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
5241 if (req
->opcode
== IORING_OP_POLL_ADD
)
5243 return &req
->apoll
->poll
;
5246 static void io_poll_remove_double(struct io_kiocb
*req
)
5248 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
5250 lockdep_assert_held(&req
->ctx
->completion_lock
);
5252 if (poll
&& poll
->head
) {
5253 struct wait_queue_head
*head
= poll
->head
;
5255 spin_lock(&head
->lock
);
5256 list_del_init(&poll
->wait
.entry
);
5257 if (poll
->wait
.private)
5258 refcount_dec(&req
->refs
);
5260 spin_unlock(&head
->lock
);
5264 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
5266 struct io_ring_ctx
*ctx
= req
->ctx
;
5268 io_poll_remove_double(req
);
5269 req
->poll
.done
= true;
5270 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
5271 io_commit_cqring(ctx
);
5274 static void io_poll_task_func(struct callback_head
*cb
)
5276 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5277 struct io_ring_ctx
*ctx
= req
->ctx
;
5278 struct io_kiocb
*nxt
;
5280 if (io_poll_rewait(req
, &req
->poll
)) {
5281 spin_unlock_irq(&ctx
->completion_lock
);
5283 hash_del(&req
->hash_node
);
5284 io_poll_complete(req
, req
->result
, 0);
5285 spin_unlock_irq(&ctx
->completion_lock
);
5287 nxt
= io_put_req_find_next(req
);
5288 io_cqring_ev_posted(ctx
);
5290 __io_req_task_submit(nxt
);
5293 percpu_ref_put(&ctx
->refs
);
5296 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
5297 int sync
, void *key
)
5299 struct io_kiocb
*req
= wait
->private;
5300 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
5301 __poll_t mask
= key_to_poll(key
);
5303 /* for instances that support it check for an event match first: */
5304 if (mask
&& !(mask
& poll
->events
))
5307 list_del_init(&wait
->entry
);
5309 if (poll
&& poll
->head
) {
5312 spin_lock(&poll
->head
->lock
);
5313 done
= list_empty(&poll
->wait
.entry
);
5315 list_del_init(&poll
->wait
.entry
);
5316 /* make sure double remove sees this as being gone */
5317 wait
->private = NULL
;
5318 spin_unlock(&poll
->head
->lock
);
5320 /* use wait func handler, so it matches the rq type */
5321 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5324 refcount_dec(&req
->refs
);
5328 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
5329 wait_queue_func_t wake_func
)
5333 poll
->canceled
= false;
5334 poll
->events
= events
;
5335 INIT_LIST_HEAD(&poll
->wait
.entry
);
5336 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5339 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5340 struct wait_queue_head
*head
,
5341 struct io_poll_iocb
**poll_ptr
)
5343 struct io_kiocb
*req
= pt
->req
;
5346 * If poll->head is already set, it's because the file being polled
5347 * uses multiple waitqueues for poll handling (eg one for read, one
5348 * for write). Setup a separate io_poll_iocb if this happens.
5350 if (unlikely(poll
->head
)) {
5351 struct io_poll_iocb
*poll_one
= poll
;
5353 /* already have a 2nd entry, fail a third attempt */
5355 pt
->error
= -EINVAL
;
5358 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5360 pt
->error
= -ENOMEM
;
5363 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5364 refcount_inc(&req
->refs
);
5365 poll
->wait
.private = req
;
5372 if (poll
->events
& EPOLLEXCLUSIVE
)
5373 add_wait_queue_exclusive(head
, &poll
->wait
);
5375 add_wait_queue(head
, &poll
->wait
);
5378 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5379 struct poll_table_struct
*p
)
5381 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5382 struct async_poll
*apoll
= pt
->req
->apoll
;
5384 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5387 static void io_async_task_func(struct callback_head
*cb
)
5389 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5390 struct async_poll
*apoll
= req
->apoll
;
5391 struct io_ring_ctx
*ctx
= req
->ctx
;
5393 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5395 if (io_poll_rewait(req
, &apoll
->poll
)) {
5396 spin_unlock_irq(&ctx
->completion_lock
);
5397 percpu_ref_put(&ctx
->refs
);
5401 /* If req is still hashed, it cannot have been canceled. Don't check. */
5402 if (hash_hashed(&req
->hash_node
))
5403 hash_del(&req
->hash_node
);
5405 io_poll_remove_double(req
);
5406 spin_unlock_irq(&ctx
->completion_lock
);
5408 if (!READ_ONCE(apoll
->poll
.canceled
))
5409 __io_req_task_submit(req
);
5411 __io_req_task_cancel(req
, -ECANCELED
);
5413 percpu_ref_put(&ctx
->refs
);
5414 kfree(apoll
->double_poll
);
5418 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5421 struct io_kiocb
*req
= wait
->private;
5422 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5424 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5427 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5430 static void io_poll_req_insert(struct io_kiocb
*req
)
5432 struct io_ring_ctx
*ctx
= req
->ctx
;
5433 struct hlist_head
*list
;
5435 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5436 hlist_add_head(&req
->hash_node
, list
);
5439 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5440 struct io_poll_iocb
*poll
,
5441 struct io_poll_table
*ipt
, __poll_t mask
,
5442 wait_queue_func_t wake_func
)
5443 __acquires(&ctx
->completion_lock
)
5445 struct io_ring_ctx
*ctx
= req
->ctx
;
5446 bool cancel
= false;
5448 INIT_HLIST_NODE(&req
->hash_node
);
5449 io_init_poll_iocb(poll
, mask
, wake_func
);
5450 poll
->file
= req
->file
;
5451 poll
->wait
.private = req
;
5453 ipt
->pt
._key
= mask
;
5455 ipt
->error
= -EINVAL
;
5457 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5459 spin_lock_irq(&ctx
->completion_lock
);
5460 if (likely(poll
->head
)) {
5461 spin_lock(&poll
->head
->lock
);
5462 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5468 if (mask
|| ipt
->error
)
5469 list_del_init(&poll
->wait
.entry
);
5471 WRITE_ONCE(poll
->canceled
, true);
5472 else if (!poll
->done
) /* actually waiting for an event */
5473 io_poll_req_insert(req
);
5474 spin_unlock(&poll
->head
->lock
);
5480 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5482 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5483 struct io_ring_ctx
*ctx
= req
->ctx
;
5484 struct async_poll
*apoll
;
5485 struct io_poll_table ipt
;
5489 if (!req
->file
|| !file_can_poll(req
->file
))
5491 if (req
->flags
& REQ_F_POLLED
)
5495 else if (def
->pollout
)
5499 /* if we can't nonblock try, then no point in arming a poll handler */
5500 if (!io_file_supports_async(req
->file
, rw
))
5503 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5504 if (unlikely(!apoll
))
5506 apoll
->double_poll
= NULL
;
5508 req
->flags
|= REQ_F_POLLED
;
5513 mask
|= POLLIN
| POLLRDNORM
;
5515 mask
|= POLLOUT
| POLLWRNORM
;
5517 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5518 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5519 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5522 mask
|= POLLERR
| POLLPRI
;
5524 ipt
.pt
._qproc
= io_async_queue_proc
;
5526 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5528 if (ret
|| ipt
.error
) {
5529 io_poll_remove_double(req
);
5530 spin_unlock_irq(&ctx
->completion_lock
);
5531 kfree(apoll
->double_poll
);
5535 spin_unlock_irq(&ctx
->completion_lock
);
5536 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5537 apoll
->poll
.events
);
5541 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5542 struct io_poll_iocb
*poll
)
5544 bool do_complete
= false;
5546 spin_lock(&poll
->head
->lock
);
5547 WRITE_ONCE(poll
->canceled
, true);
5548 if (!list_empty(&poll
->wait
.entry
)) {
5549 list_del_init(&poll
->wait
.entry
);
5552 spin_unlock(&poll
->head
->lock
);
5553 hash_del(&req
->hash_node
);
5557 static bool io_poll_remove_one(struct io_kiocb
*req
)
5561 io_poll_remove_double(req
);
5563 if (req
->opcode
== IORING_OP_POLL_ADD
) {
5564 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
5566 struct async_poll
*apoll
= req
->apoll
;
5568 /* non-poll requests have submit ref still */
5569 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
5572 kfree(apoll
->double_poll
);
5578 io_cqring_fill_event(req
, -ECANCELED
);
5579 io_commit_cqring(req
->ctx
);
5580 req_set_fail_links(req
);
5581 io_put_req_deferred(req
, 1);
5588 * Returns true if we found and killed one or more poll requests
5590 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5591 struct files_struct
*files
)
5593 struct hlist_node
*tmp
;
5594 struct io_kiocb
*req
;
5597 spin_lock_irq(&ctx
->completion_lock
);
5598 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5599 struct hlist_head
*list
;
5601 list
= &ctx
->cancel_hash
[i
];
5602 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5603 if (io_match_task(req
, tsk
, files
))
5604 posted
+= io_poll_remove_one(req
);
5607 spin_unlock_irq(&ctx
->completion_lock
);
5610 io_cqring_ev_posted(ctx
);
5615 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5617 struct hlist_head
*list
;
5618 struct io_kiocb
*req
;
5620 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5621 hlist_for_each_entry(req
, list
, hash_node
) {
5622 if (sqe_addr
!= req
->user_data
)
5624 if (io_poll_remove_one(req
))
5632 static int io_poll_remove_prep(struct io_kiocb
*req
,
5633 const struct io_uring_sqe
*sqe
)
5635 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5637 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5641 req
->poll_remove
.addr
= READ_ONCE(sqe
->addr
);
5646 * Find a running poll command that matches one specified in sqe->addr,
5647 * and remove it if found.
5649 static int io_poll_remove(struct io_kiocb
*req
, unsigned int issue_flags
)
5651 struct io_ring_ctx
*ctx
= req
->ctx
;
5654 spin_lock_irq(&ctx
->completion_lock
);
5655 ret
= io_poll_cancel(ctx
, req
->poll_remove
.addr
);
5656 spin_unlock_irq(&ctx
->completion_lock
);
5659 req_set_fail_links(req
);
5660 io_req_complete(req
, ret
);
5664 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5667 struct io_kiocb
*req
= wait
->private;
5668 struct io_poll_iocb
*poll
= &req
->poll
;
5670 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5673 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5674 struct poll_table_struct
*p
)
5676 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5678 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5681 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5683 struct io_poll_iocb
*poll
= &req
->poll
;
5686 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5688 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
5691 events
= READ_ONCE(sqe
->poll32_events
);
5693 events
= swahw32(events
);
5695 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
5696 (events
& EPOLLEXCLUSIVE
);
5700 static int io_poll_add(struct io_kiocb
*req
, unsigned int issue_flags
)
5702 struct io_poll_iocb
*poll
= &req
->poll
;
5703 struct io_ring_ctx
*ctx
= req
->ctx
;
5704 struct io_poll_table ipt
;
5707 ipt
.pt
._qproc
= io_poll_queue_proc
;
5709 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5712 if (mask
) { /* no async, we'd stolen it */
5714 io_poll_complete(req
, mask
, 0);
5716 spin_unlock_irq(&ctx
->completion_lock
);
5719 io_cqring_ev_posted(ctx
);
5725 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5727 struct io_timeout_data
*data
= container_of(timer
,
5728 struct io_timeout_data
, timer
);
5729 struct io_kiocb
*req
= data
->req
;
5730 struct io_ring_ctx
*ctx
= req
->ctx
;
5731 unsigned long flags
;
5733 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5734 list_del_init(&req
->timeout
.list
);
5735 atomic_set(&req
->ctx
->cq_timeouts
,
5736 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5738 io_cqring_fill_event(req
, -ETIME
);
5739 io_commit_cqring(ctx
);
5740 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5742 io_cqring_ev_posted(ctx
);
5743 req_set_fail_links(req
);
5745 return HRTIMER_NORESTART
;
5748 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5751 struct io_timeout_data
*io
;
5752 struct io_kiocb
*req
;
5755 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5756 if (user_data
== req
->user_data
) {
5763 return ERR_PTR(ret
);
5765 io
= req
->async_data
;
5766 ret
= hrtimer_try_to_cancel(&io
->timer
);
5768 return ERR_PTR(-EALREADY
);
5769 list_del_init(&req
->timeout
.list
);
5773 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5775 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5778 return PTR_ERR(req
);
5780 req_set_fail_links(req
);
5781 io_cqring_fill_event(req
, -ECANCELED
);
5782 io_put_req_deferred(req
, 1);
5786 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
5787 struct timespec64
*ts
, enum hrtimer_mode mode
)
5789 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5790 struct io_timeout_data
*data
;
5793 return PTR_ERR(req
);
5795 req
->timeout
.off
= 0; /* noseq */
5796 data
= req
->async_data
;
5797 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
5798 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, mode
);
5799 data
->timer
.function
= io_timeout_fn
;
5800 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
5804 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5805 const struct io_uring_sqe
*sqe
)
5807 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5809 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5811 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5813 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5816 tr
->addr
= READ_ONCE(sqe
->addr
);
5817 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
5818 if (tr
->flags
& IORING_TIMEOUT_UPDATE
) {
5819 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE
|IORING_TIMEOUT_ABS
))
5821 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
5823 } else if (tr
->flags
) {
5824 /* timeout removal doesn't support flags */
5831 static inline enum hrtimer_mode
io_translate_timeout_mode(unsigned int flags
)
5833 return (flags
& IORING_TIMEOUT_ABS
) ? HRTIMER_MODE_ABS
5838 * Remove or update an existing timeout command
5840 static int io_timeout_remove(struct io_kiocb
*req
, unsigned int issue_flags
)
5842 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5843 struct io_ring_ctx
*ctx
= req
->ctx
;
5846 spin_lock_irq(&ctx
->completion_lock
);
5847 if (!(req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
))
5848 ret
= io_timeout_cancel(ctx
, tr
->addr
);
5850 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
,
5851 io_translate_timeout_mode(tr
->flags
));
5853 io_cqring_fill_event(req
, ret
);
5854 io_commit_cqring(ctx
);
5855 spin_unlock_irq(&ctx
->completion_lock
);
5856 io_cqring_ev_posted(ctx
);
5858 req_set_fail_links(req
);
5863 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5864 bool is_timeout_link
)
5866 struct io_timeout_data
*data
;
5868 u32 off
= READ_ONCE(sqe
->off
);
5870 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5872 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5874 if (off
&& is_timeout_link
)
5876 flags
= READ_ONCE(sqe
->timeout_flags
);
5877 if (flags
& ~IORING_TIMEOUT_ABS
)
5880 req
->timeout
.off
= off
;
5882 if (!req
->async_data
&& io_alloc_async_data(req
))
5885 data
= req
->async_data
;
5888 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5891 data
->mode
= io_translate_timeout_mode(flags
);
5892 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5896 static int io_timeout(struct io_kiocb
*req
, unsigned int issue_flags
)
5898 struct io_ring_ctx
*ctx
= req
->ctx
;
5899 struct io_timeout_data
*data
= req
->async_data
;
5900 struct list_head
*entry
;
5901 u32 tail
, off
= req
->timeout
.off
;
5903 spin_lock_irq(&ctx
->completion_lock
);
5906 * sqe->off holds how many events that need to occur for this
5907 * timeout event to be satisfied. If it isn't set, then this is
5908 * a pure timeout request, sequence isn't used.
5910 if (io_is_timeout_noseq(req
)) {
5911 entry
= ctx
->timeout_list
.prev
;
5915 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5916 req
->timeout
.target_seq
= tail
+ off
;
5918 /* Update the last seq here in case io_flush_timeouts() hasn't.
5919 * This is safe because ->completion_lock is held, and submissions
5920 * and completions are never mixed in the same ->completion_lock section.
5922 ctx
->cq_last_tm_flush
= tail
;
5925 * Insertion sort, ensuring the first entry in the list is always
5926 * the one we need first.
5928 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5929 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5932 if (io_is_timeout_noseq(nxt
))
5934 /* nxt.seq is behind @tail, otherwise would've been completed */
5935 if (off
>= nxt
->timeout
.target_seq
- tail
)
5939 list_add(&req
->timeout
.list
, entry
);
5940 data
->timer
.function
= io_timeout_fn
;
5941 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5942 spin_unlock_irq(&ctx
->completion_lock
);
5946 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5948 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5950 return req
->user_data
== (unsigned long) data
;
5953 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5955 enum io_wq_cancel cancel_ret
;
5958 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5959 switch (cancel_ret
) {
5960 case IO_WQ_CANCEL_OK
:
5963 case IO_WQ_CANCEL_RUNNING
:
5966 case IO_WQ_CANCEL_NOTFOUND
:
5974 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5975 struct io_kiocb
*req
, __u64 sqe_addr
,
5978 unsigned long flags
;
5981 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5982 if (ret
!= -ENOENT
) {
5983 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5987 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5988 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5991 ret
= io_poll_cancel(ctx
, sqe_addr
);
5995 io_cqring_fill_event(req
, ret
);
5996 io_commit_cqring(ctx
);
5997 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5998 io_cqring_ev_posted(ctx
);
6001 req_set_fail_links(req
);
6005 static int io_async_cancel_prep(struct io_kiocb
*req
,
6006 const struct io_uring_sqe
*sqe
)
6008 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
6010 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
6012 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
6015 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
6019 static int io_async_cancel(struct io_kiocb
*req
, unsigned int issue_flags
)
6021 struct io_ring_ctx
*ctx
= req
->ctx
;
6023 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
6027 static int io_rsrc_update_prep(struct io_kiocb
*req
,
6028 const struct io_uring_sqe
*sqe
)
6030 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
6032 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
6034 if (sqe
->ioprio
|| sqe
->rw_flags
)
6037 req
->rsrc_update
.offset
= READ_ONCE(sqe
->off
);
6038 req
->rsrc_update
.nr_args
= READ_ONCE(sqe
->len
);
6039 if (!req
->rsrc_update
.nr_args
)
6041 req
->rsrc_update
.arg
= READ_ONCE(sqe
->addr
);
6045 static int io_files_update(struct io_kiocb
*req
, unsigned int issue_flags
)
6047 struct io_ring_ctx
*ctx
= req
->ctx
;
6048 struct io_uring_rsrc_update up
;
6051 if (issue_flags
& IO_URING_F_NONBLOCK
)
6054 up
.offset
= req
->rsrc_update
.offset
;
6055 up
.data
= req
->rsrc_update
.arg
;
6057 mutex_lock(&ctx
->uring_lock
);
6058 ret
= __io_sqe_files_update(ctx
, &up
, req
->rsrc_update
.nr_args
);
6059 mutex_unlock(&ctx
->uring_lock
);
6062 req_set_fail_links(req
);
6063 __io_req_complete(req
, issue_flags
, ret
, 0);
6067 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6069 switch (req
->opcode
) {
6072 case IORING_OP_READV
:
6073 case IORING_OP_READ_FIXED
:
6074 case IORING_OP_READ
:
6075 return io_read_prep(req
, sqe
);
6076 case IORING_OP_WRITEV
:
6077 case IORING_OP_WRITE_FIXED
:
6078 case IORING_OP_WRITE
:
6079 return io_write_prep(req
, sqe
);
6080 case IORING_OP_POLL_ADD
:
6081 return io_poll_add_prep(req
, sqe
);
6082 case IORING_OP_POLL_REMOVE
:
6083 return io_poll_remove_prep(req
, sqe
);
6084 case IORING_OP_FSYNC
:
6085 return io_fsync_prep(req
, sqe
);
6086 case IORING_OP_SYNC_FILE_RANGE
:
6087 return io_sfr_prep(req
, sqe
);
6088 case IORING_OP_SENDMSG
:
6089 case IORING_OP_SEND
:
6090 return io_sendmsg_prep(req
, sqe
);
6091 case IORING_OP_RECVMSG
:
6092 case IORING_OP_RECV
:
6093 return io_recvmsg_prep(req
, sqe
);
6094 case IORING_OP_CONNECT
:
6095 return io_connect_prep(req
, sqe
);
6096 case IORING_OP_TIMEOUT
:
6097 return io_timeout_prep(req
, sqe
, false);
6098 case IORING_OP_TIMEOUT_REMOVE
:
6099 return io_timeout_remove_prep(req
, sqe
);
6100 case IORING_OP_ASYNC_CANCEL
:
6101 return io_async_cancel_prep(req
, sqe
);
6102 case IORING_OP_LINK_TIMEOUT
:
6103 return io_timeout_prep(req
, sqe
, true);
6104 case IORING_OP_ACCEPT
:
6105 return io_accept_prep(req
, sqe
);
6106 case IORING_OP_FALLOCATE
:
6107 return io_fallocate_prep(req
, sqe
);
6108 case IORING_OP_OPENAT
:
6109 return io_openat_prep(req
, sqe
);
6110 case IORING_OP_CLOSE
:
6111 return io_close_prep(req
, sqe
);
6112 case IORING_OP_FILES_UPDATE
:
6113 return io_rsrc_update_prep(req
, sqe
);
6114 case IORING_OP_STATX
:
6115 return io_statx_prep(req
, sqe
);
6116 case IORING_OP_FADVISE
:
6117 return io_fadvise_prep(req
, sqe
);
6118 case IORING_OP_MADVISE
:
6119 return io_madvise_prep(req
, sqe
);
6120 case IORING_OP_OPENAT2
:
6121 return io_openat2_prep(req
, sqe
);
6122 case IORING_OP_EPOLL_CTL
:
6123 return io_epoll_ctl_prep(req
, sqe
);
6124 case IORING_OP_SPLICE
:
6125 return io_splice_prep(req
, sqe
);
6126 case IORING_OP_PROVIDE_BUFFERS
:
6127 return io_provide_buffers_prep(req
, sqe
);
6128 case IORING_OP_REMOVE_BUFFERS
:
6129 return io_remove_buffers_prep(req
, sqe
);
6131 return io_tee_prep(req
, sqe
);
6132 case IORING_OP_SHUTDOWN
:
6133 return io_shutdown_prep(req
, sqe
);
6134 case IORING_OP_RENAMEAT
:
6135 return io_renameat_prep(req
, sqe
);
6136 case IORING_OP_UNLINKAT
:
6137 return io_unlinkat_prep(req
, sqe
);
6140 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
6145 static int io_req_defer_prep(struct io_kiocb
*req
,
6146 const struct io_uring_sqe
*sqe
)
6150 if (io_alloc_async_data(req
))
6152 return io_req_prep(req
, sqe
);
6155 static u32
io_get_sequence(struct io_kiocb
*req
)
6157 struct io_kiocb
*pos
;
6158 struct io_ring_ctx
*ctx
= req
->ctx
;
6159 u32 total_submitted
, nr_reqs
= 0;
6161 io_for_each_link(pos
, req
)
6164 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
6165 return total_submitted
- nr_reqs
;
6168 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6170 struct io_ring_ctx
*ctx
= req
->ctx
;
6171 struct io_defer_entry
*de
;
6175 /* Still need defer if there is pending req in defer list. */
6176 if (likely(list_empty_careful(&ctx
->defer_list
) &&
6177 !(req
->flags
& REQ_F_IO_DRAIN
)))
6180 seq
= io_get_sequence(req
);
6181 /* Still a chance to pass the sequence check */
6182 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
6185 if (!req
->async_data
) {
6186 ret
= io_req_defer_prep(req
, sqe
);
6190 io_prep_async_link(req
);
6191 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
6195 spin_lock_irq(&ctx
->completion_lock
);
6196 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
6197 spin_unlock_irq(&ctx
->completion_lock
);
6199 io_queue_async_work(req
);
6200 return -EIOCBQUEUED
;
6203 trace_io_uring_defer(ctx
, req
, req
->user_data
);
6206 list_add_tail(&de
->list
, &ctx
->defer_list
);
6207 spin_unlock_irq(&ctx
->completion_lock
);
6208 return -EIOCBQUEUED
;
6211 static void __io_clean_op(struct io_kiocb
*req
)
6213 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6214 switch (req
->opcode
) {
6215 case IORING_OP_READV
:
6216 case IORING_OP_READ_FIXED
:
6217 case IORING_OP_READ
:
6218 kfree((void *)(unsigned long)req
->rw
.addr
);
6220 case IORING_OP_RECVMSG
:
6221 case IORING_OP_RECV
:
6222 kfree(req
->sr_msg
.kbuf
);
6225 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
6228 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6229 switch (req
->opcode
) {
6230 case IORING_OP_READV
:
6231 case IORING_OP_READ_FIXED
:
6232 case IORING_OP_READ
:
6233 case IORING_OP_WRITEV
:
6234 case IORING_OP_WRITE_FIXED
:
6235 case IORING_OP_WRITE
: {
6236 struct io_async_rw
*io
= req
->async_data
;
6238 kfree(io
->free_iovec
);
6241 case IORING_OP_RECVMSG
:
6242 case IORING_OP_SENDMSG
: {
6243 struct io_async_msghdr
*io
= req
->async_data
;
6245 kfree(io
->free_iov
);
6248 case IORING_OP_SPLICE
:
6250 io_put_file(req
, req
->splice
.file_in
,
6251 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
6253 case IORING_OP_OPENAT
:
6254 case IORING_OP_OPENAT2
:
6255 if (req
->open
.filename
)
6256 putname(req
->open
.filename
);
6258 case IORING_OP_RENAMEAT
:
6259 putname(req
->rename
.oldpath
);
6260 putname(req
->rename
.newpath
);
6262 case IORING_OP_UNLINKAT
:
6263 putname(req
->unlink
.filename
);
6266 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
6270 static int io_issue_sqe(struct io_kiocb
*req
, unsigned int issue_flags
)
6272 struct io_ring_ctx
*ctx
= req
->ctx
;
6275 switch (req
->opcode
) {
6277 ret
= io_nop(req
, issue_flags
);
6279 case IORING_OP_READV
:
6280 case IORING_OP_READ_FIXED
:
6281 case IORING_OP_READ
:
6282 ret
= io_read(req
, issue_flags
);
6284 case IORING_OP_WRITEV
:
6285 case IORING_OP_WRITE_FIXED
:
6286 case IORING_OP_WRITE
:
6287 ret
= io_write(req
, issue_flags
);
6289 case IORING_OP_FSYNC
:
6290 ret
= io_fsync(req
, issue_flags
);
6292 case IORING_OP_POLL_ADD
:
6293 ret
= io_poll_add(req
, issue_flags
);
6295 case IORING_OP_POLL_REMOVE
:
6296 ret
= io_poll_remove(req
, issue_flags
);
6298 case IORING_OP_SYNC_FILE_RANGE
:
6299 ret
= io_sync_file_range(req
, issue_flags
);
6301 case IORING_OP_SENDMSG
:
6302 ret
= io_sendmsg(req
, issue_flags
);
6304 case IORING_OP_SEND
:
6305 ret
= io_send(req
, issue_flags
);
6307 case IORING_OP_RECVMSG
:
6308 ret
= io_recvmsg(req
, issue_flags
);
6310 case IORING_OP_RECV
:
6311 ret
= io_recv(req
, issue_flags
);
6313 case IORING_OP_TIMEOUT
:
6314 ret
= io_timeout(req
, issue_flags
);
6316 case IORING_OP_TIMEOUT_REMOVE
:
6317 ret
= io_timeout_remove(req
, issue_flags
);
6319 case IORING_OP_ACCEPT
:
6320 ret
= io_accept(req
, issue_flags
);
6322 case IORING_OP_CONNECT
:
6323 ret
= io_connect(req
, issue_flags
);
6325 case IORING_OP_ASYNC_CANCEL
:
6326 ret
= io_async_cancel(req
, issue_flags
);
6328 case IORING_OP_FALLOCATE
:
6329 ret
= io_fallocate(req
, issue_flags
);
6331 case IORING_OP_OPENAT
:
6332 ret
= io_openat(req
, issue_flags
);
6334 case IORING_OP_CLOSE
:
6335 ret
= io_close(req
, issue_flags
);
6337 case IORING_OP_FILES_UPDATE
:
6338 ret
= io_files_update(req
, issue_flags
);
6340 case IORING_OP_STATX
:
6341 ret
= io_statx(req
, issue_flags
);
6343 case IORING_OP_FADVISE
:
6344 ret
= io_fadvise(req
, issue_flags
);
6346 case IORING_OP_MADVISE
:
6347 ret
= io_madvise(req
, issue_flags
);
6349 case IORING_OP_OPENAT2
:
6350 ret
= io_openat2(req
, issue_flags
);
6352 case IORING_OP_EPOLL_CTL
:
6353 ret
= io_epoll_ctl(req
, issue_flags
);
6355 case IORING_OP_SPLICE
:
6356 ret
= io_splice(req
, issue_flags
);
6358 case IORING_OP_PROVIDE_BUFFERS
:
6359 ret
= io_provide_buffers(req
, issue_flags
);
6361 case IORING_OP_REMOVE_BUFFERS
:
6362 ret
= io_remove_buffers(req
, issue_flags
);
6365 ret
= io_tee(req
, issue_flags
);
6367 case IORING_OP_SHUTDOWN
:
6368 ret
= io_shutdown(req
, issue_flags
);
6370 case IORING_OP_RENAMEAT
:
6371 ret
= io_renameat(req
, issue_flags
);
6373 case IORING_OP_UNLINKAT
:
6374 ret
= io_unlinkat(req
, issue_flags
);
6384 /* If the op doesn't have a file, we're not polling for it */
6385 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
6386 const bool in_async
= io_wq_current_is_worker();
6388 /* workqueue context doesn't hold uring_lock, grab it now */
6390 mutex_lock(&ctx
->uring_lock
);
6392 io_iopoll_req_issued(req
, in_async
);
6395 mutex_unlock(&ctx
->uring_lock
);
6401 static void io_wq_submit_work(struct io_wq_work
*work
)
6403 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6404 struct io_kiocb
*timeout
;
6407 timeout
= io_prep_linked_timeout(req
);
6409 io_queue_linked_timeout(timeout
);
6411 if (work
->flags
& IO_WQ_WORK_CANCEL
)
6416 ret
= io_issue_sqe(req
, 0);
6418 * We can get EAGAIN for polled IO even though we're
6419 * forcing a sync submission from here, since we can't
6420 * wait for request slots on the block side.
6429 struct io_ring_ctx
*lock_ctx
= NULL
;
6431 if (req
->ctx
->flags
& IORING_SETUP_IOPOLL
)
6432 lock_ctx
= req
->ctx
;
6435 * io_iopoll_complete() does not hold completion_lock to
6436 * complete polled io, so here for polled io, we can not call
6437 * io_req_complete() directly, otherwise there maybe concurrent
6438 * access to cqring, defer_list, etc, which is not safe. Given
6439 * that io_iopoll_complete() is always called under uring_lock,
6440 * so here for polled io, we also get uring_lock to complete
6444 mutex_lock(&lock_ctx
->uring_lock
);
6446 req_set_fail_links(req
);
6447 io_req_complete(req
, ret
);
6450 mutex_unlock(&lock_ctx
->uring_lock
);
6454 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6457 struct fixed_rsrc_table
*table
;
6459 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
6460 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
6463 static struct file
*io_file_get(struct io_submit_state
*state
,
6464 struct io_kiocb
*req
, int fd
, bool fixed
)
6466 struct io_ring_ctx
*ctx
= req
->ctx
;
6470 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6472 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6473 file
= io_file_from_index(ctx
, fd
);
6474 io_set_resource_node(req
);
6476 trace_io_uring_file_get(ctx
, fd
);
6477 file
= __io_file_get(state
, fd
);
6480 if (file
&& unlikely(file
->f_op
== &io_uring_fops
))
6481 io_req_track_inflight(req
);
6485 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6487 struct io_timeout_data
*data
= container_of(timer
,
6488 struct io_timeout_data
, timer
);
6489 struct io_kiocb
*prev
, *req
= data
->req
;
6490 struct io_ring_ctx
*ctx
= req
->ctx
;
6491 unsigned long flags
;
6493 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6494 prev
= req
->timeout
.head
;
6495 req
->timeout
.head
= NULL
;
6498 * We don't expect the list to be empty, that will only happen if we
6499 * race with the completion of the linked work.
6501 if (prev
&& refcount_inc_not_zero(&prev
->refs
))
6502 io_remove_next_linked(prev
);
6505 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6508 req_set_fail_links(prev
);
6509 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6510 io_put_req_deferred(prev
, 1);
6512 io_req_complete_post(req
, -ETIME
, 0);
6513 io_put_req_deferred(req
, 1);
6515 return HRTIMER_NORESTART
;
6518 static void __io_queue_linked_timeout(struct io_kiocb
*req
)
6521 * If the back reference is NULL, then our linked request finished
6522 * before we got a chance to setup the timer
6524 if (req
->timeout
.head
) {
6525 struct io_timeout_data
*data
= req
->async_data
;
6527 data
->timer
.function
= io_link_timeout_fn
;
6528 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6533 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6535 struct io_ring_ctx
*ctx
= req
->ctx
;
6537 spin_lock_irq(&ctx
->completion_lock
);
6538 __io_queue_linked_timeout(req
);
6539 spin_unlock_irq(&ctx
->completion_lock
);
6541 /* drop submission reference */
6545 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6547 struct io_kiocb
*nxt
= req
->link
;
6549 if (!nxt
|| (req
->flags
& REQ_F_LINK_TIMEOUT
) ||
6550 nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6553 nxt
->timeout
.head
= req
;
6554 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6555 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6559 static void __io_queue_sqe(struct io_kiocb
*req
)
6561 struct io_kiocb
*linked_timeout
= io_prep_linked_timeout(req
);
6562 const struct cred
*old_creds
= NULL
;
6565 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
6566 (req
->work
.flags
& IO_WQ_WORK_CREDS
) &&
6567 req
->work
.identity
->creds
!= current_cred())
6568 old_creds
= override_creds(req
->work
.identity
->creds
);
6570 ret
= io_issue_sqe(req
, IO_URING_F_NONBLOCK
|IO_URING_F_COMPLETE_DEFER
);
6573 revert_creds(old_creds
);
6576 * We async punt it if the file wasn't marked NOWAIT, or if the file
6577 * doesn't support non-blocking read/write attempts
6579 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6580 if (!io_arm_poll_handler(req
)) {
6582 * Queued up for async execution, worker will release
6583 * submit reference when the iocb is actually submitted.
6585 io_queue_async_work(req
);
6587 } else if (likely(!ret
)) {
6588 /* drop submission reference */
6589 if (req
->flags
& REQ_F_COMPLETE_INLINE
) {
6590 struct io_ring_ctx
*ctx
= req
->ctx
;
6591 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
6593 cs
->reqs
[cs
->nr
++] = req
;
6594 if (cs
->nr
== ARRAY_SIZE(cs
->reqs
))
6595 io_submit_flush_completions(cs
, ctx
);
6600 req_set_fail_links(req
);
6602 io_req_complete(req
, ret
);
6605 io_queue_linked_timeout(linked_timeout
);
6608 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6612 ret
= io_req_defer(req
, sqe
);
6614 if (ret
!= -EIOCBQUEUED
) {
6616 req_set_fail_links(req
);
6618 io_req_complete(req
, ret
);
6620 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6621 if (!req
->async_data
) {
6622 ret
= io_req_defer_prep(req
, sqe
);
6626 io_queue_async_work(req
);
6629 ret
= io_req_prep(req
, sqe
);
6633 __io_queue_sqe(req
);
6637 static inline void io_queue_link_head(struct io_kiocb
*req
)
6639 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6641 io_req_complete(req
, -ECANCELED
);
6643 io_queue_sqe(req
, NULL
);
6647 * Check SQE restrictions (opcode and flags).
6649 * Returns 'true' if SQE is allowed, 'false' otherwise.
6651 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6652 struct io_kiocb
*req
,
6653 unsigned int sqe_flags
)
6655 if (!ctx
->restricted
)
6658 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6661 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6662 ctx
->restrictions
.sqe_flags_required
)
6665 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6666 ctx
->restrictions
.sqe_flags_required
))
6672 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6673 const struct io_uring_sqe
*sqe
)
6675 struct io_submit_state
*state
;
6676 unsigned int sqe_flags
;
6679 req
->opcode
= READ_ONCE(sqe
->opcode
);
6680 /* same numerical values with corresponding REQ_F_*, safe to copy */
6681 req
->flags
= sqe_flags
= READ_ONCE(sqe
->flags
);
6682 req
->user_data
= READ_ONCE(sqe
->user_data
);
6683 req
->async_data
= NULL
;
6687 req
->fixed_rsrc_refs
= NULL
;
6688 /* one is dropped after submission, the other at completion */
6689 refcount_set(&req
->refs
, 2);
6690 req
->task
= current
;
6693 /* enforce forwards compatibility on users */
6694 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6697 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6700 if (unlikely(io_sq_thread_acquire_mm_files(ctx
, req
)))
6703 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6706 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6707 !io_op_defs
[req
->opcode
].buffer_select
)
6710 id
= READ_ONCE(sqe
->personality
);
6712 struct io_identity
*iod
;
6714 iod
= idr_find(&ctx
->personality_idr
, id
);
6717 refcount_inc(&iod
->count
);
6719 __io_req_init_async(req
);
6720 get_cred(iod
->creds
);
6721 req
->work
.identity
= iod
;
6722 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
6725 state
= &ctx
->submit_state
;
6728 * Plug now if we have more than 1 IO left after this, and the target
6729 * is potentially a read/write to block based storage.
6731 if (!state
->plug_started
&& state
->ios_left
> 1 &&
6732 io_op_defs
[req
->opcode
].plug
) {
6733 blk_start_plug(&state
->plug
);
6734 state
->plug_started
= true;
6737 if (io_op_defs
[req
->opcode
].needs_file
) {
6738 bool fixed
= req
->flags
& REQ_F_FIXED_FILE
;
6740 req
->file
= io_file_get(state
, req
, READ_ONCE(sqe
->fd
), fixed
);
6741 if (unlikely(!req
->file
))
6749 struct io_submit_link
{
6750 struct io_kiocb
*head
;
6751 struct io_kiocb
*last
;
6754 static int io_submit_sqe(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6755 const struct io_uring_sqe
*sqe
,
6756 struct io_submit_link
*link
)
6760 ret
= io_init_req(ctx
, req
, sqe
);
6761 if (unlikely(ret
)) {
6764 io_req_complete(req
, ret
);
6768 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6769 true, ctx
->flags
& IORING_SETUP_SQPOLL
);
6772 * If we already have a head request, queue this one for async
6773 * submittal once the head completes. If we don't have a head but
6774 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6775 * submitted sync once the chain is complete. If none of those
6776 * conditions are true (normal request), then just queue it.
6779 struct io_kiocb
*head
= link
->head
;
6782 * Taking sequential execution of a link, draining both sides
6783 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6784 * requests in the link. So, it drains the head and the
6785 * next after the link request. The last one is done via
6786 * drain_next flag to persist the effect across calls.
6788 if (req
->flags
& REQ_F_IO_DRAIN
) {
6789 head
->flags
|= REQ_F_IO_DRAIN
;
6790 ctx
->drain_next
= 1;
6792 ret
= io_req_defer_prep(req
, sqe
);
6793 if (unlikely(ret
)) {
6794 /* fail even hard links since we don't submit */
6795 head
->flags
|= REQ_F_FAIL_LINK
;
6798 trace_io_uring_link(ctx
, req
, head
);
6799 link
->last
->link
= req
;
6802 /* last request of a link, enqueue the link */
6803 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6804 io_queue_link_head(head
);
6808 if (unlikely(ctx
->drain_next
)) {
6809 req
->flags
|= REQ_F_IO_DRAIN
;
6810 ctx
->drain_next
= 0;
6812 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6813 ret
= io_req_defer_prep(req
, sqe
);
6815 req
->flags
|= REQ_F_FAIL_LINK
;
6819 io_queue_sqe(req
, sqe
);
6827 * Batched submission is done, ensure local IO is flushed out.
6829 static void io_submit_state_end(struct io_submit_state
*state
,
6830 struct io_ring_ctx
*ctx
)
6833 io_submit_flush_completions(&state
->comp
, ctx
);
6834 if (state
->plug_started
)
6835 blk_finish_plug(&state
->plug
);
6836 io_state_file_put(state
);
6840 * Start submission side cache.
6842 static void io_submit_state_start(struct io_submit_state
*state
,
6843 unsigned int max_ios
)
6845 state
->plug_started
= false;
6846 state
->ios_left
= max_ios
;
6849 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6851 struct io_rings
*rings
= ctx
->rings
;
6854 * Ensure any loads from the SQEs are done at this point,
6855 * since once we write the new head, the application could
6856 * write new data to them.
6858 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6862 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6863 * that is mapped by userspace. This means that care needs to be taken to
6864 * ensure that reads are stable, as we cannot rely on userspace always
6865 * being a good citizen. If members of the sqe are validated and then later
6866 * used, it's important that those reads are done through READ_ONCE() to
6867 * prevent a re-load down the line.
6869 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6871 u32
*sq_array
= ctx
->sq_array
;
6875 * The cached sq head (or cq tail) serves two purposes:
6877 * 1) allows us to batch the cost of updating the user visible
6879 * 2) allows the kernel side to track the head on its own, even
6880 * though the application is the one updating it.
6882 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
++ & ctx
->sq_mask
]);
6883 if (likely(head
< ctx
->sq_entries
))
6884 return &ctx
->sq_sqes
[head
];
6886 /* drop invalid entries */
6887 ctx
->cached_sq_dropped
++;
6888 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6892 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6894 struct io_submit_link link
;
6897 /* if we have a backlog and couldn't flush it all, return BUSY */
6898 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6899 if (!__io_cqring_overflow_flush(ctx
, false, NULL
, NULL
))
6903 /* make sure SQ entry isn't read before tail */
6904 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6906 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6909 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6910 refcount_add(nr
, ¤t
->usage
);
6912 io_submit_state_start(&ctx
->submit_state
, nr
);
6915 while (submitted
< nr
) {
6916 const struct io_uring_sqe
*sqe
;
6917 struct io_kiocb
*req
;
6919 req
= io_alloc_req(ctx
);
6920 if (unlikely(!req
)) {
6922 submitted
= -EAGAIN
;
6925 sqe
= io_get_sqe(ctx
);
6926 if (unlikely(!sqe
)) {
6927 kmem_cache_free(req_cachep
, req
);
6930 /* will complete beyond this point, count as submitted */
6932 if (io_submit_sqe(ctx
, req
, sqe
, &link
))
6936 if (unlikely(submitted
!= nr
)) {
6937 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6938 struct io_uring_task
*tctx
= current
->io_uring
;
6939 int unused
= nr
- ref_used
;
6941 percpu_ref_put_many(&ctx
->refs
, unused
);
6942 percpu_counter_sub(&tctx
->inflight
, unused
);
6943 put_task_struct_many(current
, unused
);
6946 io_queue_link_head(link
.head
);
6947 io_submit_state_end(&ctx
->submit_state
, ctx
);
6949 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6950 io_commit_sqring(ctx
);
6955 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6957 /* Tell userspace we may need a wakeup call */
6958 spin_lock_irq(&ctx
->completion_lock
);
6959 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6960 spin_unlock_irq(&ctx
->completion_lock
);
6963 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6965 spin_lock_irq(&ctx
->completion_lock
);
6966 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6967 spin_unlock_irq(&ctx
->completion_lock
);
6970 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
6972 unsigned int to_submit
;
6975 to_submit
= io_sqring_entries(ctx
);
6976 /* if we're handling multiple rings, cap submit size for fairness */
6977 if (cap_entries
&& to_submit
> 8)
6980 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
6981 unsigned nr_events
= 0;
6983 mutex_lock(&ctx
->uring_lock
);
6984 if (!list_empty(&ctx
->iopoll_list
))
6985 io_do_iopoll(ctx
, &nr_events
, 0);
6987 if (to_submit
&& !ctx
->sqo_dead
&&
6988 likely(!percpu_ref_is_dying(&ctx
->refs
)))
6989 ret
= io_submit_sqes(ctx
, to_submit
);
6990 mutex_unlock(&ctx
->uring_lock
);
6993 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
6994 wake_up(&ctx
->sqo_sq_wait
);
6999 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
7001 struct io_ring_ctx
*ctx
;
7002 unsigned sq_thread_idle
= 0;
7004 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7005 if (sq_thread_idle
< ctx
->sq_thread_idle
)
7006 sq_thread_idle
= ctx
->sq_thread_idle
;
7009 sqd
->sq_thread_idle
= sq_thread_idle
;
7012 static void io_sqd_init_new(struct io_sq_data
*sqd
)
7014 struct io_ring_ctx
*ctx
;
7016 while (!list_empty(&sqd
->ctx_new_list
)) {
7017 ctx
= list_first_entry(&sqd
->ctx_new_list
, struct io_ring_ctx
, sqd_list
);
7018 list_move_tail(&ctx
->sqd_list
, &sqd
->ctx_list
);
7019 complete(&ctx
->sq_thread_comp
);
7022 io_sqd_update_thread_idle(sqd
);
7025 static int io_sq_thread(void *data
)
7027 struct cgroup_subsys_state
*cur_css
= NULL
;
7028 struct files_struct
*old_files
= current
->files
;
7029 struct nsproxy
*old_nsproxy
= current
->nsproxy
;
7030 const struct cred
*old_cred
= NULL
;
7031 struct io_sq_data
*sqd
= data
;
7032 struct io_ring_ctx
*ctx
;
7033 unsigned long timeout
= 0;
7037 current
->files
= NULL
;
7038 current
->nsproxy
= NULL
;
7039 task_unlock(current
);
7041 while (!kthread_should_stop()) {
7043 bool cap_entries
, sqt_spin
, needs_sched
;
7046 * Any changes to the sqd lists are synchronized through the
7047 * kthread parking. This synchronizes the thread vs users,
7048 * the users are synchronized on the sqd->ctx_lock.
7050 if (kthread_should_park()) {
7053 * When sq thread is unparked, in case the previous park operation
7054 * comes from io_put_sq_data(), which means that sq thread is going
7055 * to be stopped, so here needs to have a check.
7057 if (kthread_should_stop())
7061 if (unlikely(!list_empty(&sqd
->ctx_new_list
))) {
7062 io_sqd_init_new(sqd
);
7063 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7067 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
7068 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7069 if (current
->cred
!= ctx
->creds
) {
7071 revert_creds(old_cred
);
7072 old_cred
= override_creds(ctx
->creds
);
7074 io_sq_thread_associate_blkcg(ctx
, &cur_css
);
7076 current
->loginuid
= ctx
->loginuid
;
7077 current
->sessionid
= ctx
->sessionid
;
7080 ret
= __io_sq_thread(ctx
, cap_entries
);
7081 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
7084 io_sq_thread_drop_mm_files();
7087 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
7089 io_sq_thread_drop_mm_files();
7092 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7097 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
7098 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7099 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
7100 !list_empty_careful(&ctx
->iopoll_list
)) {
7101 needs_sched
= false;
7104 if (io_sqring_entries(ctx
)) {
7105 needs_sched
= false;
7110 if (needs_sched
&& !kthread_should_park()) {
7111 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7112 io_ring_set_wakeup_flag(ctx
);
7115 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7116 io_ring_clear_wakeup_flag(ctx
);
7119 finish_wait(&sqd
->wait
, &wait
);
7120 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7124 io_sq_thread_drop_mm_files();
7127 io_sq_thread_unassociate_blkcg();
7129 revert_creds(old_cred
);
7132 current
->files
= old_files
;
7133 current
->nsproxy
= old_nsproxy
;
7134 task_unlock(current
);
7141 struct io_wait_queue
{
7142 struct wait_queue_entry wq
;
7143 struct io_ring_ctx
*ctx
;
7145 unsigned nr_timeouts
;
7148 static inline bool io_should_wake(struct io_wait_queue
*iowq
)
7150 struct io_ring_ctx
*ctx
= iowq
->ctx
;
7153 * Wake up if we have enough events, or if a timeout occurred since we
7154 * started waiting. For timeouts, we always want to return to userspace,
7155 * regardless of event count.
7157 return io_cqring_events(ctx
) >= iowq
->to_wait
||
7158 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
7161 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
7162 int wake_flags
, void *key
)
7164 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
7168 * Cannot safely flush overflowed CQEs from here, ensure we wake up
7169 * the task, and the next invocation will do it.
7171 if (io_should_wake(iowq
) || test_bit(0, &iowq
->ctx
->cq_check_overflow
))
7172 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
7176 static int io_run_task_work_sig(void)
7178 if (io_run_task_work())
7180 if (!signal_pending(current
))
7182 if (test_tsk_thread_flag(current
, TIF_NOTIFY_SIGNAL
))
7183 return -ERESTARTSYS
;
7187 /* when returns >0, the caller should retry */
7188 static inline int io_cqring_wait_schedule(struct io_ring_ctx
*ctx
,
7189 struct io_wait_queue
*iowq
,
7190 signed long *timeout
)
7194 /* make sure we run task_work before checking for signals */
7195 ret
= io_run_task_work_sig();
7196 if (ret
|| io_should_wake(iowq
))
7198 /* let the caller flush overflows, retry */
7199 if (test_bit(0, &ctx
->cq_check_overflow
))
7202 *timeout
= schedule_timeout(*timeout
);
7203 return !*timeout
? -ETIME
: 1;
7207 * Wait until events become available, if we don't already have some. The
7208 * application must reap them itself, as they reside on the shared cq ring.
7210 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
7211 const sigset_t __user
*sig
, size_t sigsz
,
7212 struct __kernel_timespec __user
*uts
)
7214 struct io_wait_queue iowq
= {
7217 .func
= io_wake_function
,
7218 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
7221 .to_wait
= min_events
,
7223 struct io_rings
*rings
= ctx
->rings
;
7224 signed long timeout
= MAX_SCHEDULE_TIMEOUT
;
7228 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
7229 if (io_cqring_events(ctx
) >= min_events
)
7231 if (!io_run_task_work())
7236 #ifdef CONFIG_COMPAT
7237 if (in_compat_syscall())
7238 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
7242 ret
= set_user_sigmask(sig
, sigsz
);
7249 struct timespec64 ts
;
7251 if (get_timespec64(&ts
, uts
))
7253 timeout
= timespec64_to_jiffies(&ts
);
7256 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
7257 trace_io_uring_cqring_wait(ctx
, min_events
);
7259 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
7260 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
7261 TASK_INTERRUPTIBLE
);
7262 ret
= io_cqring_wait_schedule(ctx
, &iowq
, &timeout
);
7263 finish_wait(&ctx
->wait
, &iowq
.wq
);
7266 restore_saved_sigmask_unless(ret
== -EINTR
);
7268 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7271 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7273 #if defined(CONFIG_UNIX)
7274 if (ctx
->ring_sock
) {
7275 struct sock
*sock
= ctx
->ring_sock
->sk
;
7276 struct sk_buff
*skb
;
7278 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7284 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7287 file
= io_file_from_index(ctx
, i
);
7294 static void io_rsrc_data_ref_zero(struct percpu_ref
*ref
)
7296 struct fixed_rsrc_data
*data
;
7298 data
= container_of(ref
, struct fixed_rsrc_data
, refs
);
7299 complete(&data
->done
);
7302 static inline void io_rsrc_ref_lock(struct io_ring_ctx
*ctx
)
7304 spin_lock_bh(&ctx
->rsrc_ref_lock
);
7307 static inline void io_rsrc_ref_unlock(struct io_ring_ctx
*ctx
)
7309 spin_unlock_bh(&ctx
->rsrc_ref_lock
);
7312 static void io_sqe_rsrc_set_node(struct io_ring_ctx
*ctx
,
7313 struct fixed_rsrc_data
*rsrc_data
,
7314 struct fixed_rsrc_ref_node
*ref_node
)
7316 io_rsrc_ref_lock(ctx
);
7317 rsrc_data
->node
= ref_node
;
7318 list_add_tail(&ref_node
->node
, &ctx
->rsrc_ref_list
);
7319 io_rsrc_ref_unlock(ctx
);
7320 percpu_ref_get(&rsrc_data
->refs
);
7323 static int io_rsrc_ref_quiesce(struct fixed_rsrc_data
*data
,
7324 struct io_ring_ctx
*ctx
,
7325 struct fixed_rsrc_ref_node
*backup_node
)
7327 struct fixed_rsrc_ref_node
*ref_node
;
7330 io_rsrc_ref_lock(ctx
);
7331 ref_node
= data
->node
;
7332 io_rsrc_ref_unlock(ctx
);
7334 percpu_ref_kill(&ref_node
->refs
);
7336 percpu_ref_kill(&data
->refs
);
7338 /* wait for all refs nodes to complete */
7339 flush_delayed_work(&ctx
->rsrc_put_work
);
7341 ret
= wait_for_completion_interruptible(&data
->done
);
7344 ret
= io_run_task_work_sig();
7346 percpu_ref_resurrect(&data
->refs
);
7347 reinit_completion(&data
->done
);
7348 io_sqe_rsrc_set_node(ctx
, data
, backup_node
);
7353 destroy_fixed_rsrc_ref_node(backup_node
);
7357 static struct fixed_rsrc_data
*alloc_fixed_rsrc_data(struct io_ring_ctx
*ctx
)
7359 struct fixed_rsrc_data
*data
;
7361 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
7365 if (percpu_ref_init(&data
->refs
, io_rsrc_data_ref_zero
,
7366 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
)) {
7371 init_completion(&data
->done
);
7375 static void free_fixed_rsrc_data(struct fixed_rsrc_data
*data
)
7377 percpu_ref_exit(&data
->refs
);
7382 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7384 struct fixed_rsrc_data
*data
= ctx
->file_data
;
7385 struct fixed_rsrc_ref_node
*backup_node
;
7386 unsigned nr_tables
, i
;
7391 backup_node
= alloc_fixed_rsrc_ref_node(ctx
);
7394 init_fixed_file_ref_node(ctx
, backup_node
);
7396 ret
= io_rsrc_ref_quiesce(data
, ctx
, backup_node
);
7400 __io_sqe_files_unregister(ctx
);
7401 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
7402 for (i
= 0; i
< nr_tables
; i
++)
7403 kfree(data
->table
[i
].files
);
7404 free_fixed_rsrc_data(data
);
7405 ctx
->file_data
= NULL
;
7406 ctx
->nr_user_files
= 0;
7410 static void io_put_sq_data(struct io_sq_data
*sqd
)
7412 if (refcount_dec_and_test(&sqd
->refs
)) {
7414 * The park is a bit of a work-around, without it we get
7415 * warning spews on shutdown with SQPOLL set and affinity
7416 * set to a single CPU.
7419 kthread_park(sqd
->thread
);
7420 kthread_stop(sqd
->thread
);
7427 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7429 struct io_ring_ctx
*ctx_attach
;
7430 struct io_sq_data
*sqd
;
7433 f
= fdget(p
->wq_fd
);
7435 return ERR_PTR(-ENXIO
);
7436 if (f
.file
->f_op
!= &io_uring_fops
) {
7438 return ERR_PTR(-EINVAL
);
7441 ctx_attach
= f
.file
->private_data
;
7442 sqd
= ctx_attach
->sq_data
;
7445 return ERR_PTR(-EINVAL
);
7448 refcount_inc(&sqd
->refs
);
7453 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
)
7455 struct io_sq_data
*sqd
;
7457 if (p
->flags
& IORING_SETUP_ATTACH_WQ
)
7458 return io_attach_sq_data(p
);
7460 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7462 return ERR_PTR(-ENOMEM
);
7464 refcount_set(&sqd
->refs
, 1);
7465 INIT_LIST_HEAD(&sqd
->ctx_list
);
7466 INIT_LIST_HEAD(&sqd
->ctx_new_list
);
7467 mutex_init(&sqd
->ctx_lock
);
7468 mutex_init(&sqd
->lock
);
7469 init_waitqueue_head(&sqd
->wait
);
7473 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7474 __releases(&sqd
->lock
)
7478 kthread_unpark(sqd
->thread
);
7479 mutex_unlock(&sqd
->lock
);
7482 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7483 __acquires(&sqd
->lock
)
7487 mutex_lock(&sqd
->lock
);
7488 kthread_park(sqd
->thread
);
7491 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
7493 struct io_sq_data
*sqd
= ctx
->sq_data
;
7498 * We may arrive here from the error branch in
7499 * io_sq_offload_create() where the kthread is created
7500 * without being waked up, thus wake it up now to make
7501 * sure the wait will complete.
7503 wake_up_process(sqd
->thread
);
7504 wait_for_completion(&ctx
->sq_thread_comp
);
7506 io_sq_thread_park(sqd
);
7509 mutex_lock(&sqd
->ctx_lock
);
7510 list_del(&ctx
->sqd_list
);
7511 io_sqd_update_thread_idle(sqd
);
7512 mutex_unlock(&sqd
->ctx_lock
);
7515 io_sq_thread_unpark(sqd
);
7517 io_put_sq_data(sqd
);
7518 ctx
->sq_data
= NULL
;
7522 static void io_finish_async(struct io_ring_ctx
*ctx
)
7524 io_sq_thread_stop(ctx
);
7527 io_wq_destroy(ctx
->io_wq
);
7532 #if defined(CONFIG_UNIX)
7534 * Ensure the UNIX gc is aware of our file set, so we are certain that
7535 * the io_uring can be safely unregistered on process exit, even if we have
7536 * loops in the file referencing.
7538 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7540 struct sock
*sk
= ctx
->ring_sock
->sk
;
7541 struct scm_fp_list
*fpl
;
7542 struct sk_buff
*skb
;
7545 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7549 skb
= alloc_skb(0, GFP_KERNEL
);
7558 fpl
->user
= get_uid(ctx
->user
);
7559 for (i
= 0; i
< nr
; i
++) {
7560 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7564 fpl
->fp
[nr_files
] = get_file(file
);
7565 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7570 fpl
->max
= SCM_MAX_FD
;
7571 fpl
->count
= nr_files
;
7572 UNIXCB(skb
).fp
= fpl
;
7573 skb
->destructor
= unix_destruct_scm
;
7574 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7575 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7577 for (i
= 0; i
< nr_files
; i
++)
7588 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7589 * causes regular reference counting to break down. We rely on the UNIX
7590 * garbage collection to take care of this problem for us.
7592 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7594 unsigned left
, total
;
7598 left
= ctx
->nr_user_files
;
7600 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7602 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7606 total
+= this_files
;
7612 while (total
< ctx
->nr_user_files
) {
7613 struct file
*file
= io_file_from_index(ctx
, total
);
7623 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7629 static int io_sqe_alloc_file_tables(struct fixed_rsrc_data
*file_data
,
7630 unsigned nr_tables
, unsigned nr_files
)
7634 for (i
= 0; i
< nr_tables
; i
++) {
7635 struct fixed_rsrc_table
*table
= &file_data
->table
[i
];
7636 unsigned this_files
;
7638 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7639 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
7643 nr_files
-= this_files
;
7649 for (i
= 0; i
< nr_tables
; i
++) {
7650 struct fixed_rsrc_table
*table
= &file_data
->table
[i
];
7651 kfree(table
->files
);
7656 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
7658 struct file
*file
= prsrc
->file
;
7659 #if defined(CONFIG_UNIX)
7660 struct sock
*sock
= ctx
->ring_sock
->sk
;
7661 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7662 struct sk_buff
*skb
;
7665 __skb_queue_head_init(&list
);
7668 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7669 * remove this entry and rearrange the file array.
7671 skb
= skb_dequeue(head
);
7673 struct scm_fp_list
*fp
;
7675 fp
= UNIXCB(skb
).fp
;
7676 for (i
= 0; i
< fp
->count
; i
++) {
7679 if (fp
->fp
[i
] != file
)
7682 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7683 left
= fp
->count
- 1 - i
;
7685 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7686 left
* sizeof(struct file
*));
7693 __skb_queue_tail(&list
, skb
);
7703 __skb_queue_tail(&list
, skb
);
7705 skb
= skb_dequeue(head
);
7708 if (skb_peek(&list
)) {
7709 spin_lock_irq(&head
->lock
);
7710 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7711 __skb_queue_tail(head
, skb
);
7712 spin_unlock_irq(&head
->lock
);
7719 static void __io_rsrc_put_work(struct fixed_rsrc_ref_node
*ref_node
)
7721 struct fixed_rsrc_data
*rsrc_data
= ref_node
->rsrc_data
;
7722 struct io_ring_ctx
*ctx
= rsrc_data
->ctx
;
7723 struct io_rsrc_put
*prsrc
, *tmp
;
7725 list_for_each_entry_safe(prsrc
, tmp
, &ref_node
->rsrc_list
, list
) {
7726 list_del(&prsrc
->list
);
7727 ref_node
->rsrc_put(ctx
, prsrc
);
7731 percpu_ref_exit(&ref_node
->refs
);
7733 percpu_ref_put(&rsrc_data
->refs
);
7736 static void io_rsrc_put_work(struct work_struct
*work
)
7738 struct io_ring_ctx
*ctx
;
7739 struct llist_node
*node
;
7741 ctx
= container_of(work
, struct io_ring_ctx
, rsrc_put_work
.work
);
7742 node
= llist_del_all(&ctx
->rsrc_put_llist
);
7745 struct fixed_rsrc_ref_node
*ref_node
;
7746 struct llist_node
*next
= node
->next
;
7748 ref_node
= llist_entry(node
, struct fixed_rsrc_ref_node
, llist
);
7749 __io_rsrc_put_work(ref_node
);
7754 static struct file
**io_fixed_file_slot(struct fixed_rsrc_data
*file_data
,
7757 struct fixed_rsrc_table
*table
;
7759 table
= &file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7760 return &table
->files
[i
& IORING_FILE_TABLE_MASK
];
7763 static void io_rsrc_node_ref_zero(struct percpu_ref
*ref
)
7765 struct fixed_rsrc_ref_node
*ref_node
;
7766 struct fixed_rsrc_data
*data
;
7767 struct io_ring_ctx
*ctx
;
7768 bool first_add
= false;
7771 ref_node
= container_of(ref
, struct fixed_rsrc_ref_node
, refs
);
7772 data
= ref_node
->rsrc_data
;
7775 io_rsrc_ref_lock(ctx
);
7776 ref_node
->done
= true;
7778 while (!list_empty(&ctx
->rsrc_ref_list
)) {
7779 ref_node
= list_first_entry(&ctx
->rsrc_ref_list
,
7780 struct fixed_rsrc_ref_node
, node
);
7781 /* recycle ref nodes in order */
7782 if (!ref_node
->done
)
7784 list_del(&ref_node
->node
);
7785 first_add
|= llist_add(&ref_node
->llist
, &ctx
->rsrc_put_llist
);
7787 io_rsrc_ref_unlock(ctx
);
7789 if (percpu_ref_is_dying(&data
->refs
))
7793 mod_delayed_work(system_wq
, &ctx
->rsrc_put_work
, 0);
7795 queue_delayed_work(system_wq
, &ctx
->rsrc_put_work
, delay
);
7798 static struct fixed_rsrc_ref_node
*alloc_fixed_rsrc_ref_node(
7799 struct io_ring_ctx
*ctx
)
7801 struct fixed_rsrc_ref_node
*ref_node
;
7803 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7807 if (percpu_ref_init(&ref_node
->refs
, io_rsrc_node_ref_zero
,
7812 INIT_LIST_HEAD(&ref_node
->node
);
7813 INIT_LIST_HEAD(&ref_node
->rsrc_list
);
7814 ref_node
->done
= false;
7818 static void init_fixed_file_ref_node(struct io_ring_ctx
*ctx
,
7819 struct fixed_rsrc_ref_node
*ref_node
)
7821 ref_node
->rsrc_data
= ctx
->file_data
;
7822 ref_node
->rsrc_put
= io_ring_file_put
;
7825 static void destroy_fixed_rsrc_ref_node(struct fixed_rsrc_ref_node
*ref_node
)
7827 percpu_ref_exit(&ref_node
->refs
);
7832 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7835 __s32 __user
*fds
= (__s32 __user
*) arg
;
7836 unsigned nr_tables
, i
;
7838 int fd
, ret
= -ENOMEM
;
7839 struct fixed_rsrc_ref_node
*ref_node
;
7840 struct fixed_rsrc_data
*file_data
;
7846 if (nr_args
> IORING_MAX_FIXED_FILES
)
7849 file_data
= alloc_fixed_rsrc_data(ctx
);
7852 ctx
->file_data
= file_data
;
7854 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7855 file_data
->table
= kcalloc(nr_tables
, sizeof(*file_data
->table
),
7857 if (!file_data
->table
)
7860 if (io_sqe_alloc_file_tables(file_data
, nr_tables
, nr_args
))
7863 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7864 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7868 /* allow sparse sets */
7878 * Don't allow io_uring instances to be registered. If UNIX
7879 * isn't enabled, then this causes a reference cycle and this
7880 * instance can never get freed. If UNIX is enabled we'll
7881 * handle it just fine, but there's still no point in allowing
7882 * a ring fd as it doesn't support regular read/write anyway.
7884 if (file
->f_op
== &io_uring_fops
) {
7888 *io_fixed_file_slot(file_data
, i
) = file
;
7891 ret
= io_sqe_files_scm(ctx
);
7893 io_sqe_files_unregister(ctx
);
7897 ref_node
= alloc_fixed_rsrc_ref_node(ctx
);
7899 io_sqe_files_unregister(ctx
);
7902 init_fixed_file_ref_node(ctx
, ref_node
);
7904 io_sqe_rsrc_set_node(ctx
, file_data
, ref_node
);
7907 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7908 file
= io_file_from_index(ctx
, i
);
7912 for (i
= 0; i
< nr_tables
; i
++)
7913 kfree(file_data
->table
[i
].files
);
7914 ctx
->nr_user_files
= 0;
7916 free_fixed_rsrc_data(ctx
->file_data
);
7917 ctx
->file_data
= NULL
;
7921 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7924 #if defined(CONFIG_UNIX)
7925 struct sock
*sock
= ctx
->ring_sock
->sk
;
7926 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7927 struct sk_buff
*skb
;
7930 * See if we can merge this file into an existing skb SCM_RIGHTS
7931 * file set. If there's no room, fall back to allocating a new skb
7932 * and filling it in.
7934 spin_lock_irq(&head
->lock
);
7935 skb
= skb_peek(head
);
7937 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7939 if (fpl
->count
< SCM_MAX_FD
) {
7940 __skb_unlink(skb
, head
);
7941 spin_unlock_irq(&head
->lock
);
7942 fpl
->fp
[fpl
->count
] = get_file(file
);
7943 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7945 spin_lock_irq(&head
->lock
);
7946 __skb_queue_head(head
, skb
);
7951 spin_unlock_irq(&head
->lock
);
7958 return __io_sqe_files_scm(ctx
, 1, index
);
7964 static int io_queue_rsrc_removal(struct fixed_rsrc_data
*data
, void *rsrc
)
7966 struct io_rsrc_put
*prsrc
;
7967 struct fixed_rsrc_ref_node
*ref_node
= data
->node
;
7969 prsrc
= kzalloc(sizeof(*prsrc
), GFP_KERNEL
);
7974 list_add(&prsrc
->list
, &ref_node
->rsrc_list
);
7979 static inline int io_queue_file_removal(struct fixed_rsrc_data
*data
,
7982 return io_queue_rsrc_removal(data
, (void *)file
);
7985 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7986 struct io_uring_rsrc_update
*up
,
7989 struct fixed_rsrc_data
*data
= ctx
->file_data
;
7990 struct fixed_rsrc_ref_node
*ref_node
;
7991 struct file
*file
, **file_slot
;
7995 bool needs_switch
= false;
7997 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7999 if (done
> ctx
->nr_user_files
)
8002 ref_node
= alloc_fixed_rsrc_ref_node(ctx
);
8005 init_fixed_file_ref_node(ctx
, ref_node
);
8007 fds
= u64_to_user_ptr(up
->data
);
8008 for (done
= 0; done
< nr_args
; done
++) {
8010 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
8014 if (fd
== IORING_REGISTER_FILES_SKIP
)
8017 i
= array_index_nospec(up
->offset
+ done
, ctx
->nr_user_files
);
8018 file_slot
= io_fixed_file_slot(ctx
->file_data
, i
);
8021 err
= io_queue_file_removal(data
, *file_slot
);
8025 needs_switch
= true;
8034 * Don't allow io_uring instances to be registered. If
8035 * UNIX isn't enabled, then this causes a reference
8036 * cycle and this instance can never get freed. If UNIX
8037 * is enabled we'll handle it just fine, but there's
8038 * still no point in allowing a ring fd as it doesn't
8039 * support regular read/write anyway.
8041 if (file
->f_op
== &io_uring_fops
) {
8047 err
= io_sqe_file_register(ctx
, file
, i
);
8057 percpu_ref_kill(&data
->node
->refs
);
8058 io_sqe_rsrc_set_node(ctx
, data
, ref_node
);
8060 destroy_fixed_rsrc_ref_node(ref_node
);
8062 return done
? done
: err
;
8065 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
8068 struct io_uring_rsrc_update up
;
8070 if (!ctx
->file_data
)
8074 if (copy_from_user(&up
, arg
, sizeof(up
)))
8079 return __io_sqe_files_update(ctx
, &up
, nr_args
);
8082 static struct io_wq_work
*io_free_work(struct io_wq_work
*work
)
8084 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8086 req
= io_put_req_find_next(req
);
8087 return req
? &req
->work
: NULL
;
8090 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
8091 struct io_uring_params
*p
)
8093 struct io_wq_data data
;
8095 struct io_ring_ctx
*ctx_attach
;
8096 unsigned int concurrency
;
8099 data
.user
= ctx
->user
;
8100 data
.free_work
= io_free_work
;
8101 data
.do_work
= io_wq_submit_work
;
8103 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
8104 /* Do QD, or 4 * CPUS, whatever is smallest */
8105 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
8107 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
8108 if (IS_ERR(ctx
->io_wq
)) {
8109 ret
= PTR_ERR(ctx
->io_wq
);
8115 f
= fdget(p
->wq_fd
);
8119 if (f
.file
->f_op
!= &io_uring_fops
) {
8124 ctx_attach
= f
.file
->private_data
;
8125 /* @io_wq is protected by holding the fd */
8126 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
8131 ctx
->io_wq
= ctx_attach
->io_wq
;
8137 static int io_uring_alloc_task_context(struct task_struct
*task
)
8139 struct io_uring_task
*tctx
;
8142 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
8143 if (unlikely(!tctx
))
8146 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
8147 if (unlikely(ret
)) {
8153 init_waitqueue_head(&tctx
->wait
);
8155 atomic_set(&tctx
->in_idle
, 0);
8156 tctx
->sqpoll
= false;
8157 io_init_identity(&tctx
->__identity
);
8158 tctx
->identity
= &tctx
->__identity
;
8159 task
->io_uring
= tctx
;
8160 spin_lock_init(&tctx
->task_lock
);
8161 INIT_WQ_LIST(&tctx
->task_list
);
8162 tctx
->task_state
= 0;
8163 init_task_work(&tctx
->task_work
, tctx_task_work
);
8167 void __io_uring_free(struct task_struct
*tsk
)
8169 struct io_uring_task
*tctx
= tsk
->io_uring
;
8171 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
8172 WARN_ON_ONCE(refcount_read(&tctx
->identity
->count
) != 1);
8173 if (tctx
->identity
!= &tctx
->__identity
)
8174 kfree(tctx
->identity
);
8175 percpu_counter_destroy(&tctx
->inflight
);
8177 tsk
->io_uring
= NULL
;
8180 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
8181 struct io_uring_params
*p
)
8185 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8186 struct io_sq_data
*sqd
;
8189 if (!capable(CAP_SYS_ADMIN
) && !capable(CAP_SYS_NICE
))
8192 sqd
= io_get_sq_data(p
);
8199 io_sq_thread_park(sqd
);
8200 mutex_lock(&sqd
->ctx_lock
);
8201 list_add(&ctx
->sqd_list
, &sqd
->ctx_new_list
);
8202 mutex_unlock(&sqd
->ctx_lock
);
8203 io_sq_thread_unpark(sqd
);
8205 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
8206 if (!ctx
->sq_thread_idle
)
8207 ctx
->sq_thread_idle
= HZ
;
8212 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8213 int cpu
= p
->sq_thread_cpu
;
8216 if (cpu
>= nr_cpu_ids
)
8218 if (!cpu_online(cpu
))
8221 sqd
->thread
= kthread_create_on_cpu(io_sq_thread
, sqd
,
8222 cpu
, "io_uring-sq");
8224 sqd
->thread
= kthread_create(io_sq_thread
, sqd
,
8227 if (IS_ERR(sqd
->thread
)) {
8228 ret
= PTR_ERR(sqd
->thread
);
8232 ret
= io_uring_alloc_task_context(sqd
->thread
);
8235 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8236 /* Can't have SQ_AFF without SQPOLL */
8242 ret
= io_init_wq_offload(ctx
, p
);
8248 io_finish_async(ctx
);
8252 static void io_sq_offload_start(struct io_ring_ctx
*ctx
)
8254 struct io_sq_data
*sqd
= ctx
->sq_data
;
8256 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && sqd
->thread
)
8257 wake_up_process(sqd
->thread
);
8260 static inline void __io_unaccount_mem(struct user_struct
*user
,
8261 unsigned long nr_pages
)
8263 atomic_long_sub(nr_pages
, &user
->locked_vm
);
8266 static inline int __io_account_mem(struct user_struct
*user
,
8267 unsigned long nr_pages
)
8269 unsigned long page_limit
, cur_pages
, new_pages
;
8271 /* Don't allow more pages than we can safely lock */
8272 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
8275 cur_pages
= atomic_long_read(&user
->locked_vm
);
8276 new_pages
= cur_pages
+ nr_pages
;
8277 if (new_pages
> page_limit
)
8279 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
8280 new_pages
) != cur_pages
);
8285 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8288 __io_unaccount_mem(ctx
->user
, nr_pages
);
8290 if (ctx
->mm_account
)
8291 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8294 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8298 if (ctx
->limit_mem
) {
8299 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8304 if (ctx
->mm_account
)
8305 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8310 static void io_mem_free(void *ptr
)
8317 page
= virt_to_head_page(ptr
);
8318 if (put_page_testzero(page
))
8319 free_compound_page(page
);
8322 static void *io_mem_alloc(size_t size
)
8324 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8325 __GFP_NORETRY
| __GFP_ACCOUNT
;
8327 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8330 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8333 struct io_rings
*rings
;
8334 size_t off
, sq_array_size
;
8336 off
= struct_size(rings
, cqes
, cq_entries
);
8337 if (off
== SIZE_MAX
)
8341 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8349 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8350 if (sq_array_size
== SIZE_MAX
)
8353 if (check_add_overflow(off
, sq_array_size
, &off
))
8359 static int io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8363 if (!ctx
->user_bufs
)
8366 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8367 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8369 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
8370 unpin_user_page(imu
->bvec
[j
].bv_page
);
8372 if (imu
->acct_pages
)
8373 io_unaccount_mem(ctx
, imu
->acct_pages
);
8378 kfree(ctx
->user_bufs
);
8379 ctx
->user_bufs
= NULL
;
8380 ctx
->nr_user_bufs
= 0;
8384 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8385 void __user
*arg
, unsigned index
)
8387 struct iovec __user
*src
;
8389 #ifdef CONFIG_COMPAT
8391 struct compat_iovec __user
*ciovs
;
8392 struct compat_iovec ciov
;
8394 ciovs
= (struct compat_iovec __user
*) arg
;
8395 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8398 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8399 dst
->iov_len
= ciov
.iov_len
;
8403 src
= (struct iovec __user
*) arg
;
8404 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8410 * Not super efficient, but this is just a registration time. And we do cache
8411 * the last compound head, so generally we'll only do a full search if we don't
8414 * We check if the given compound head page has already been accounted, to
8415 * avoid double accounting it. This allows us to account the full size of the
8416 * page, not just the constituent pages of a huge page.
8418 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8419 int nr_pages
, struct page
*hpage
)
8423 /* check current page array */
8424 for (i
= 0; i
< nr_pages
; i
++) {
8425 if (!PageCompound(pages
[i
]))
8427 if (compound_head(pages
[i
]) == hpage
)
8431 /* check previously registered pages */
8432 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8433 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8435 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8436 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8438 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8446 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8447 int nr_pages
, struct io_mapped_ubuf
*imu
,
8448 struct page
**last_hpage
)
8452 for (i
= 0; i
< nr_pages
; i
++) {
8453 if (!PageCompound(pages
[i
])) {
8458 hpage
= compound_head(pages
[i
]);
8459 if (hpage
== *last_hpage
)
8461 *last_hpage
= hpage
;
8462 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8464 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8468 if (!imu
->acct_pages
)
8471 ret
= io_account_mem(ctx
, imu
->acct_pages
);
8473 imu
->acct_pages
= 0;
8477 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, struct iovec
*iov
,
8478 struct io_mapped_ubuf
*imu
,
8479 struct page
**last_hpage
)
8481 struct vm_area_struct
**vmas
= NULL
;
8482 struct page
**pages
= NULL
;
8483 unsigned long off
, start
, end
, ubuf
;
8485 int ret
, pret
, nr_pages
, i
;
8487 ubuf
= (unsigned long) iov
->iov_base
;
8488 end
= (ubuf
+ iov
->iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8489 start
= ubuf
>> PAGE_SHIFT
;
8490 nr_pages
= end
- start
;
8494 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*), GFP_KERNEL
);
8498 vmas
= kvmalloc_array(nr_pages
, sizeof(struct vm_area_struct
*),
8503 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8509 mmap_read_lock(current
->mm
);
8510 pret
= pin_user_pages(ubuf
, nr_pages
, FOLL_WRITE
| FOLL_LONGTERM
,
8512 if (pret
== nr_pages
) {
8513 /* don't support file backed memory */
8514 for (i
= 0; i
< nr_pages
; i
++) {
8515 struct vm_area_struct
*vma
= vmas
[i
];
8518 !is_file_hugepages(vma
->vm_file
)) {
8524 ret
= pret
< 0 ? pret
: -EFAULT
;
8526 mmap_read_unlock(current
->mm
);
8529 * if we did partial map, or found file backed vmas,
8530 * release any pages we did get
8533 unpin_user_pages(pages
, pret
);
8538 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, last_hpage
);
8540 unpin_user_pages(pages
, pret
);
8545 off
= ubuf
& ~PAGE_MASK
;
8546 size
= iov
->iov_len
;
8547 for (i
= 0; i
< nr_pages
; i
++) {
8550 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8551 imu
->bvec
[i
].bv_page
= pages
[i
];
8552 imu
->bvec
[i
].bv_len
= vec_len
;
8553 imu
->bvec
[i
].bv_offset
= off
;
8557 /* store original address for later verification */
8559 imu
->len
= iov
->iov_len
;
8560 imu
->nr_bvecs
= nr_pages
;
8568 static int io_buffers_map_alloc(struct io_ring_ctx
*ctx
, unsigned int nr_args
)
8572 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8575 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
8577 if (!ctx
->user_bufs
)
8583 static int io_buffer_validate(struct iovec
*iov
)
8586 * Don't impose further limits on the size and buffer
8587 * constraints here, we'll -EINVAL later when IO is
8588 * submitted if they are wrong.
8590 if (!iov
->iov_base
|| !iov
->iov_len
)
8593 /* arbitrary limit, but we need something */
8594 if (iov
->iov_len
> SZ_1G
)
8600 static int io_sqe_buffers_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8601 unsigned int nr_args
)
8605 struct page
*last_hpage
= NULL
;
8607 ret
= io_buffers_map_alloc(ctx
, nr_args
);
8611 for (i
= 0; i
< nr_args
; i
++) {
8612 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8614 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8618 ret
= io_buffer_validate(&iov
);
8622 ret
= io_sqe_buffer_register(ctx
, &iov
, imu
, &last_hpage
);
8626 ctx
->nr_user_bufs
++;
8630 io_sqe_buffers_unregister(ctx
);
8635 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8637 __s32 __user
*fds
= arg
;
8643 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8646 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8647 if (IS_ERR(ctx
->cq_ev_fd
)) {
8648 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8649 ctx
->cq_ev_fd
= NULL
;
8656 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8658 if (ctx
->cq_ev_fd
) {
8659 eventfd_ctx_put(ctx
->cq_ev_fd
);
8660 ctx
->cq_ev_fd
= NULL
;
8667 static int __io_destroy_buffers(int id
, void *p
, void *data
)
8669 struct io_ring_ctx
*ctx
= data
;
8670 struct io_buffer
*buf
= p
;
8672 __io_remove_buffers(ctx
, buf
, id
, -1U);
8676 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8678 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
8679 idr_destroy(&ctx
->io_buffer_idr
);
8682 static void io_req_cache_free(struct list_head
*list
, struct task_struct
*tsk
)
8684 struct io_kiocb
*req
, *nxt
;
8686 list_for_each_entry_safe(req
, nxt
, list
, compl.list
) {
8687 if (tsk
&& req
->task
!= tsk
)
8689 list_del(&req
->compl.list
);
8690 kmem_cache_free(req_cachep
, req
);
8694 static void io_req_caches_free(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
)
8696 struct io_submit_state
*submit_state
= &ctx
->submit_state
;
8698 mutex_lock(&ctx
->uring_lock
);
8700 if (submit_state
->free_reqs
)
8701 kmem_cache_free_bulk(req_cachep
, submit_state
->free_reqs
,
8702 submit_state
->reqs
);
8704 io_req_cache_free(&submit_state
->comp
.free_list
, NULL
);
8706 spin_lock_irq(&ctx
->completion_lock
);
8707 io_req_cache_free(&submit_state
->comp
.locked_free_list
, NULL
);
8708 spin_unlock_irq(&ctx
->completion_lock
);
8710 mutex_unlock(&ctx
->uring_lock
);
8713 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8716 * Some may use context even when all refs and requests have been put,
8717 * and they are free to do so while still holding uring_lock, see
8718 * __io_req_task_submit(). Wait for them to finish.
8720 mutex_lock(&ctx
->uring_lock
);
8721 mutex_unlock(&ctx
->uring_lock
);
8723 io_finish_async(ctx
);
8724 io_sqe_buffers_unregister(ctx
);
8726 if (ctx
->sqo_task
) {
8727 put_task_struct(ctx
->sqo_task
);
8728 ctx
->sqo_task
= NULL
;
8729 mmdrop(ctx
->mm_account
);
8730 ctx
->mm_account
= NULL
;
8733 #ifdef CONFIG_BLK_CGROUP
8734 if (ctx
->sqo_blkcg_css
)
8735 css_put(ctx
->sqo_blkcg_css
);
8738 io_sqe_files_unregister(ctx
);
8739 io_eventfd_unregister(ctx
);
8740 io_destroy_buffers(ctx
);
8741 idr_destroy(&ctx
->personality_idr
);
8743 #if defined(CONFIG_UNIX)
8744 if (ctx
->ring_sock
) {
8745 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8746 sock_release(ctx
->ring_sock
);
8750 io_mem_free(ctx
->rings
);
8751 io_mem_free(ctx
->sq_sqes
);
8753 percpu_ref_exit(&ctx
->refs
);
8754 free_uid(ctx
->user
);
8755 put_cred(ctx
->creds
);
8756 io_req_caches_free(ctx
, NULL
);
8757 kfree(ctx
->cancel_hash
);
8761 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8763 struct io_ring_ctx
*ctx
= file
->private_data
;
8766 poll_wait(file
, &ctx
->cq_wait
, wait
);
8768 * synchronizes with barrier from wq_has_sleeper call in
8772 if (!io_sqring_full(ctx
))
8773 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8776 * Don't flush cqring overflow list here, just do a simple check.
8777 * Otherwise there could possible be ABBA deadlock:
8780 * lock(&ctx->uring_lock);
8782 * lock(&ctx->uring_lock);
8785 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
8786 * pushs them to do the flush.
8788 if (io_cqring_events(ctx
) || test_bit(0, &ctx
->cq_check_overflow
))
8789 mask
|= EPOLLIN
| EPOLLRDNORM
;
8794 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8796 struct io_ring_ctx
*ctx
= file
->private_data
;
8798 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8801 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
8803 struct io_identity
*iod
;
8805 iod
= idr_remove(&ctx
->personality_idr
, id
);
8807 put_cred(iod
->creds
);
8808 if (refcount_dec_and_test(&iod
->count
))
8816 static int io_remove_personalities(int id
, void *p
, void *data
)
8818 struct io_ring_ctx
*ctx
= data
;
8820 io_unregister_personality(ctx
, id
);
8824 static void io_ring_exit_work(struct work_struct
*work
)
8826 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
8830 * If we're doing polled IO and end up having requests being
8831 * submitted async (out-of-line), then completions can come in while
8832 * we're waiting for refs to drop. We need to reap these manually,
8833 * as nobody else will be looking for them.
8836 io_uring_try_cancel_requests(ctx
, NULL
, NULL
);
8837 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8838 io_ring_ctx_free(ctx
);
8841 static bool io_cancel_ctx_cb(struct io_wq_work
*work
, void *data
)
8843 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8845 return req
->ctx
== data
;
8848 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8850 mutex_lock(&ctx
->uring_lock
);
8851 percpu_ref_kill(&ctx
->refs
);
8853 if (WARN_ON_ONCE((ctx
->flags
& IORING_SETUP_SQPOLL
) && !ctx
->sqo_dead
))
8856 /* if force is set, the ring is going away. always drop after that */
8857 ctx
->cq_overflow_flushed
= 1;
8859 __io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8860 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
8861 mutex_unlock(&ctx
->uring_lock
);
8863 io_kill_timeouts(ctx
, NULL
, NULL
);
8864 io_poll_remove_all(ctx
, NULL
, NULL
);
8867 io_wq_cancel_cb(ctx
->io_wq
, io_cancel_ctx_cb
, ctx
, true);
8869 /* if we failed setting up the ctx, we might not have any rings */
8870 io_iopoll_try_reap_events(ctx
);
8872 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8874 * Use system_unbound_wq to avoid spawning tons of event kworkers
8875 * if we're exiting a ton of rings at the same time. It just adds
8876 * noise and overhead, there's no discernable change in runtime
8877 * over using system_wq.
8879 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8882 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8884 struct io_ring_ctx
*ctx
= file
->private_data
;
8886 file
->private_data
= NULL
;
8887 io_ring_ctx_wait_and_kill(ctx
);
8891 struct io_task_cancel
{
8892 struct task_struct
*task
;
8893 struct files_struct
*files
;
8896 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8898 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8899 struct io_task_cancel
*cancel
= data
;
8902 if (cancel
->files
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
8903 unsigned long flags
;
8904 struct io_ring_ctx
*ctx
= req
->ctx
;
8906 /* protect against races with linked timeouts */
8907 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
8908 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8909 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
8911 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8916 static void io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8917 struct task_struct
*task
,
8918 struct files_struct
*files
)
8920 struct io_defer_entry
*de
= NULL
;
8923 spin_lock_irq(&ctx
->completion_lock
);
8924 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8925 if (io_match_task(de
->req
, task
, files
)) {
8926 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8930 spin_unlock_irq(&ctx
->completion_lock
);
8932 while (!list_empty(&list
)) {
8933 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8934 list_del_init(&de
->list
);
8935 req_set_fail_links(de
->req
);
8936 io_put_req(de
->req
);
8937 io_req_complete(de
->req
, -ECANCELED
);
8942 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
8943 struct task_struct
*task
,
8944 struct files_struct
*files
)
8946 struct io_task_cancel cancel
= { .task
= task
, .files
= files
, };
8949 enum io_wq_cancel cret
;
8953 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
,
8955 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
8958 /* SQPOLL thread does its own polling */
8959 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
) && !files
) {
8960 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8961 io_iopoll_try_reap_events(ctx
);
8966 ret
|= io_poll_remove_all(ctx
, task
, files
);
8967 ret
|= io_kill_timeouts(ctx
, task
, files
);
8968 ret
|= io_run_task_work();
8969 io_cqring_overflow_flush(ctx
, true, task
, files
);
8976 static int io_uring_count_inflight(struct io_ring_ctx
*ctx
,
8977 struct task_struct
*task
,
8978 struct files_struct
*files
)
8980 struct io_kiocb
*req
;
8983 spin_lock_irq(&ctx
->inflight_lock
);
8984 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
)
8985 cnt
+= io_match_task(req
, task
, files
);
8986 spin_unlock_irq(&ctx
->inflight_lock
);
8990 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8991 struct task_struct
*task
,
8992 struct files_struct
*files
)
8994 while (!list_empty_careful(&ctx
->inflight_list
)) {
8998 inflight
= io_uring_count_inflight(ctx
, task
, files
);
9002 io_uring_try_cancel_requests(ctx
, task
, files
);
9005 io_sq_thread_unpark(ctx
->sq_data
);
9006 prepare_to_wait(&task
->io_uring
->wait
, &wait
,
9007 TASK_UNINTERRUPTIBLE
);
9008 if (inflight
== io_uring_count_inflight(ctx
, task
, files
))
9010 finish_wait(&task
->io_uring
->wait
, &wait
);
9012 io_sq_thread_park(ctx
->sq_data
);
9016 static void io_disable_sqo_submit(struct io_ring_ctx
*ctx
)
9018 mutex_lock(&ctx
->uring_lock
);
9020 mutex_unlock(&ctx
->uring_lock
);
9022 /* make sure callers enter the ring to get error */
9024 io_ring_set_wakeup_flag(ctx
);
9028 * We need to iteratively cancel requests, in case a request has dependent
9029 * hard links. These persist even for failure of cancelations, hence keep
9030 * looping until none are found.
9032 static void io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
9033 struct files_struct
*files
)
9035 struct task_struct
*task
= current
;
9037 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
) {
9038 io_disable_sqo_submit(ctx
);
9039 task
= ctx
->sq_data
->thread
;
9040 atomic_inc(&task
->io_uring
->in_idle
);
9041 io_sq_thread_park(ctx
->sq_data
);
9044 io_cancel_defer_files(ctx
, task
, files
);
9046 io_uring_cancel_files(ctx
, task
, files
);
9048 io_uring_try_cancel_requests(ctx
, task
, NULL
);
9050 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
) {
9051 atomic_dec(&task
->io_uring
->in_idle
);
9053 * If the files that are going away are the ones in the thread
9054 * identity, clear them out.
9056 if (task
->io_uring
->identity
->files
== files
)
9057 task
->io_uring
->identity
->files
= NULL
;
9058 io_sq_thread_unpark(ctx
->sq_data
);
9063 * Note that this task has used io_uring. We use it for cancelation purposes.
9065 static int io_uring_add_task_file(struct io_ring_ctx
*ctx
, struct file
*file
)
9067 struct io_uring_task
*tctx
= current
->io_uring
;
9070 if (unlikely(!tctx
)) {
9071 ret
= io_uring_alloc_task_context(current
);
9074 tctx
= current
->io_uring
;
9076 if (tctx
->last
!= file
) {
9077 void *old
= xa_load(&tctx
->xa
, (unsigned long)file
);
9081 ret
= xa_err(xa_store(&tctx
->xa
, (unsigned long)file
,
9088 /* one and only SQPOLL file note, held by sqo_task */
9089 WARN_ON_ONCE((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
9090 current
!= ctx
->sqo_task
);
9096 * This is race safe in that the task itself is doing this, hence it
9097 * cannot be going through the exit/cancel paths at the same time.
9098 * This cannot be modified while exit/cancel is running.
9100 if (!tctx
->sqpoll
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
9101 tctx
->sqpoll
= true;
9107 * Remove this io_uring_file -> task mapping.
9109 static void io_uring_del_task_file(struct file
*file
)
9111 struct io_uring_task
*tctx
= current
->io_uring
;
9113 if (tctx
->last
== file
)
9115 file
= xa_erase(&tctx
->xa
, (unsigned long)file
);
9120 static void io_uring_remove_task_files(struct io_uring_task
*tctx
)
9123 unsigned long index
;
9125 xa_for_each(&tctx
->xa
, index
, file
)
9126 io_uring_del_task_file(file
);
9129 void __io_uring_files_cancel(struct files_struct
*files
)
9131 struct io_uring_task
*tctx
= current
->io_uring
;
9133 unsigned long index
;
9135 /* make sure overflow events are dropped */
9136 atomic_inc(&tctx
->in_idle
);
9137 xa_for_each(&tctx
->xa
, index
, file
)
9138 io_uring_cancel_task_requests(file
->private_data
, files
);
9139 atomic_dec(&tctx
->in_idle
);
9142 io_uring_remove_task_files(tctx
);
9145 static s64
tctx_inflight(struct io_uring_task
*tctx
)
9147 return percpu_counter_sum(&tctx
->inflight
);
9150 static void io_uring_cancel_sqpoll(struct io_ring_ctx
*ctx
)
9152 struct io_uring_task
*tctx
;
9158 tctx
= ctx
->sq_data
->thread
->io_uring
;
9159 io_disable_sqo_submit(ctx
);
9161 atomic_inc(&tctx
->in_idle
);
9163 /* read completions before cancelations */
9164 inflight
= tctx_inflight(tctx
);
9167 io_uring_cancel_task_requests(ctx
, NULL
);
9169 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
9171 * If we've seen completions, retry without waiting. This
9172 * avoids a race where a completion comes in before we did
9173 * prepare_to_wait().
9175 if (inflight
== tctx_inflight(tctx
))
9177 finish_wait(&tctx
->wait
, &wait
);
9179 atomic_dec(&tctx
->in_idle
);
9183 * Find any io_uring fd that this task has registered or done IO on, and cancel
9186 void __io_uring_task_cancel(void)
9188 struct io_uring_task
*tctx
= current
->io_uring
;
9192 /* make sure overflow events are dropped */
9193 atomic_inc(&tctx
->in_idle
);
9195 /* trigger io_disable_sqo_submit() */
9198 unsigned long index
;
9200 xa_for_each(&tctx
->xa
, index
, file
)
9201 io_uring_cancel_sqpoll(file
->private_data
);
9205 /* read completions before cancelations */
9206 inflight
= tctx_inflight(tctx
);
9209 __io_uring_files_cancel(NULL
);
9211 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
9214 * If we've seen completions, retry without waiting. This
9215 * avoids a race where a completion comes in before we did
9216 * prepare_to_wait().
9218 if (inflight
== tctx_inflight(tctx
))
9220 finish_wait(&tctx
->wait
, &wait
);
9223 atomic_dec(&tctx
->in_idle
);
9225 io_uring_remove_task_files(tctx
);
9228 static int io_uring_flush(struct file
*file
, void *data
)
9230 struct io_uring_task
*tctx
= current
->io_uring
;
9231 struct io_ring_ctx
*ctx
= file
->private_data
;
9233 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
)) {
9234 io_uring_cancel_task_requests(ctx
, NULL
);
9235 io_req_caches_free(ctx
, current
);
9241 /* we should have cancelled and erased it before PF_EXITING */
9242 WARN_ON_ONCE((current
->flags
& PF_EXITING
) &&
9243 xa_load(&tctx
->xa
, (unsigned long)file
));
9246 * fput() is pending, will be 2 if the only other ref is our potential
9247 * task file note. If the task is exiting, drop regardless of count.
9249 if (atomic_long_read(&file
->f_count
) != 2)
9252 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9253 /* there is only one file note, which is owned by sqo_task */
9254 WARN_ON_ONCE(ctx
->sqo_task
!= current
&&
9255 xa_load(&tctx
->xa
, (unsigned long)file
));
9256 /* sqo_dead check is for when this happens after cancellation */
9257 WARN_ON_ONCE(ctx
->sqo_task
== current
&& !ctx
->sqo_dead
&&
9258 !xa_load(&tctx
->xa
, (unsigned long)file
));
9260 io_disable_sqo_submit(ctx
);
9263 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
) || ctx
->sqo_task
== current
)
9264 io_uring_del_task_file(file
);
9268 static void *io_uring_validate_mmap_request(struct file
*file
,
9269 loff_t pgoff
, size_t sz
)
9271 struct io_ring_ctx
*ctx
= file
->private_data
;
9272 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9277 case IORING_OFF_SQ_RING
:
9278 case IORING_OFF_CQ_RING
:
9281 case IORING_OFF_SQES
:
9285 return ERR_PTR(-EINVAL
);
9288 page
= virt_to_head_page(ptr
);
9289 if (sz
> page_size(page
))
9290 return ERR_PTR(-EINVAL
);
9297 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9299 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9303 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9305 return PTR_ERR(ptr
);
9307 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9308 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9311 #else /* !CONFIG_MMU */
9313 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9315 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9318 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9320 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9323 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9324 unsigned long addr
, unsigned long len
,
9325 unsigned long pgoff
, unsigned long flags
)
9329 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9331 return PTR_ERR(ptr
);
9333 return (unsigned long) ptr
;
9336 #endif /* !CONFIG_MMU */
9338 static int io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9344 if (!io_sqring_full(ctx
))
9347 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9349 if (unlikely(ctx
->sqo_dead
)) {
9354 if (!io_sqring_full(ctx
))
9358 } while (!signal_pending(current
));
9360 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9365 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9366 struct __kernel_timespec __user
**ts
,
9367 const sigset_t __user
**sig
)
9369 struct io_uring_getevents_arg arg
;
9372 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9373 * is just a pointer to the sigset_t.
9375 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9376 *sig
= (const sigset_t __user
*) argp
;
9382 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9383 * timespec and sigset_t pointers if good.
9385 if (*argsz
!= sizeof(arg
))
9387 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9389 *sig
= u64_to_user_ptr(arg
.sigmask
);
9390 *argsz
= arg
.sigmask_sz
;
9391 *ts
= u64_to_user_ptr(arg
.ts
);
9395 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9396 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9399 struct io_ring_ctx
*ctx
;
9406 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9407 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
))
9415 if (f
.file
->f_op
!= &io_uring_fops
)
9419 ctx
= f
.file
->private_data
;
9420 if (!percpu_ref_tryget(&ctx
->refs
))
9424 if (ctx
->flags
& IORING_SETUP_R_DISABLED
)
9428 * For SQ polling, the thread will do all submissions and completions.
9429 * Just return the requested submit count, and wake the thread if
9433 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9434 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
9437 if (unlikely(ctx
->sqo_dead
))
9439 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9440 wake_up(&ctx
->sq_data
->wait
);
9441 if (flags
& IORING_ENTER_SQ_WAIT
) {
9442 ret
= io_sqpoll_wait_sq(ctx
);
9446 submitted
= to_submit
;
9447 } else if (to_submit
) {
9448 ret
= io_uring_add_task_file(ctx
, f
.file
);
9451 mutex_lock(&ctx
->uring_lock
);
9452 submitted
= io_submit_sqes(ctx
, to_submit
);
9453 mutex_unlock(&ctx
->uring_lock
);
9455 if (submitted
!= to_submit
)
9458 if (flags
& IORING_ENTER_GETEVENTS
) {
9459 const sigset_t __user
*sig
;
9460 struct __kernel_timespec __user
*ts
;
9462 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
9466 min_complete
= min(min_complete
, ctx
->cq_entries
);
9469 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9470 * space applications don't need to do io completion events
9471 * polling again, they can rely on io_sq_thread to do polling
9472 * work, which can reduce cpu usage and uring_lock contention.
9474 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
9475 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9476 ret
= io_iopoll_check(ctx
, min_complete
);
9478 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
9483 percpu_ref_put(&ctx
->refs
);
9486 return submitted
? submitted
: ret
;
9489 #ifdef CONFIG_PROC_FS
9490 static int io_uring_show_cred(int id
, void *p
, void *data
)
9492 struct io_identity
*iod
= p
;
9493 const struct cred
*cred
= iod
->creds
;
9494 struct seq_file
*m
= data
;
9495 struct user_namespace
*uns
= seq_user_ns(m
);
9496 struct group_info
*gi
;
9501 seq_printf(m
, "%5d\n", id
);
9502 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
9503 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
9504 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
9505 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
9506 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
9507 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
9508 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
9509 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
9510 seq_puts(m
, "\n\tGroups:\t");
9511 gi
= cred
->group_info
;
9512 for (g
= 0; g
< gi
->ngroups
; g
++) {
9513 seq_put_decimal_ull(m
, g
? " " : "",
9514 from_kgid_munged(uns
, gi
->gid
[g
]));
9516 seq_puts(m
, "\n\tCapEff:\t");
9517 cap
= cred
->cap_effective
;
9518 CAP_FOR_EACH_U32(__capi
)
9519 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
9524 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
9526 struct io_sq_data
*sq
= NULL
;
9531 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9532 * since fdinfo case grabs it in the opposite direction of normal use
9533 * cases. If we fail to get the lock, we just don't iterate any
9534 * structures that could be going away outside the io_uring mutex.
9536 has_lock
= mutex_trylock(&ctx
->uring_lock
);
9538 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
9541 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
9542 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
9543 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
9544 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
9545 struct file
*f
= *io_fixed_file_slot(ctx
->file_data
, i
);
9548 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
9550 seq_printf(m
, "%5u: <none>\n", i
);
9552 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
9553 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
9554 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
9556 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
9557 (unsigned int) buf
->len
);
9559 if (has_lock
&& !idr_is_empty(&ctx
->personality_idr
)) {
9560 seq_printf(m
, "Personalities:\n");
9561 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
9563 seq_printf(m
, "PollList:\n");
9564 spin_lock_irq(&ctx
->completion_lock
);
9565 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9566 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9567 struct io_kiocb
*req
;
9569 hlist_for_each_entry(req
, list
, hash_node
)
9570 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9571 req
->task
->task_works
!= NULL
);
9573 spin_unlock_irq(&ctx
->completion_lock
);
9575 mutex_unlock(&ctx
->uring_lock
);
9578 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9580 struct io_ring_ctx
*ctx
= f
->private_data
;
9582 if (percpu_ref_tryget(&ctx
->refs
)) {
9583 __io_uring_show_fdinfo(ctx
, m
);
9584 percpu_ref_put(&ctx
->refs
);
9589 static const struct file_operations io_uring_fops
= {
9590 .release
= io_uring_release
,
9591 .flush
= io_uring_flush
,
9592 .mmap
= io_uring_mmap
,
9594 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9595 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9597 .poll
= io_uring_poll
,
9598 .fasync
= io_uring_fasync
,
9599 #ifdef CONFIG_PROC_FS
9600 .show_fdinfo
= io_uring_show_fdinfo
,
9604 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9605 struct io_uring_params
*p
)
9607 struct io_rings
*rings
;
9608 size_t size
, sq_array_offset
;
9610 /* make sure these are sane, as we already accounted them */
9611 ctx
->sq_entries
= p
->sq_entries
;
9612 ctx
->cq_entries
= p
->cq_entries
;
9614 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9615 if (size
== SIZE_MAX
)
9618 rings
= io_mem_alloc(size
);
9623 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9624 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9625 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9626 rings
->sq_ring_entries
= p
->sq_entries
;
9627 rings
->cq_ring_entries
= p
->cq_entries
;
9628 ctx
->sq_mask
= rings
->sq_ring_mask
;
9629 ctx
->cq_mask
= rings
->cq_ring_mask
;
9631 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9632 if (size
== SIZE_MAX
) {
9633 io_mem_free(ctx
->rings
);
9638 ctx
->sq_sqes
= io_mem_alloc(size
);
9639 if (!ctx
->sq_sqes
) {
9640 io_mem_free(ctx
->rings
);
9648 static int io_uring_install_fd(struct io_ring_ctx
*ctx
, struct file
*file
)
9652 fd
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9656 ret
= io_uring_add_task_file(ctx
, file
);
9661 fd_install(fd
, file
);
9666 * Allocate an anonymous fd, this is what constitutes the application
9667 * visible backing of an io_uring instance. The application mmaps this
9668 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9669 * we have to tie this fd to a socket for file garbage collection purposes.
9671 static struct file
*io_uring_get_file(struct io_ring_ctx
*ctx
)
9674 #if defined(CONFIG_UNIX)
9677 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9680 return ERR_PTR(ret
);
9683 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9684 O_RDWR
| O_CLOEXEC
);
9685 #if defined(CONFIG_UNIX)
9687 sock_release(ctx
->ring_sock
);
9688 ctx
->ring_sock
= NULL
;
9690 ctx
->ring_sock
->file
= file
;
9696 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9697 struct io_uring_params __user
*params
)
9699 struct user_struct
*user
= NULL
;
9700 struct io_ring_ctx
*ctx
;
9706 if (entries
> IORING_MAX_ENTRIES
) {
9707 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9709 entries
= IORING_MAX_ENTRIES
;
9713 * Use twice as many entries for the CQ ring. It's possible for the
9714 * application to drive a higher depth than the size of the SQ ring,
9715 * since the sqes are only used at submission time. This allows for
9716 * some flexibility in overcommitting a bit. If the application has
9717 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9718 * of CQ ring entries manually.
9720 p
->sq_entries
= roundup_pow_of_two(entries
);
9721 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9723 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9724 * to a power-of-two, if it isn't already. We do NOT impose
9725 * any cq vs sq ring sizing.
9729 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9730 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9732 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9734 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9735 if (p
->cq_entries
< p
->sq_entries
)
9738 p
->cq_entries
= 2 * p
->sq_entries
;
9741 user
= get_uid(current_user());
9743 ctx
= io_ring_ctx_alloc(p
);
9748 ctx
->compat
= in_compat_syscall();
9749 ctx
->limit_mem
= !capable(CAP_IPC_LOCK
);
9751 ctx
->creds
= get_current_cred();
9753 ctx
->loginuid
= current
->loginuid
;
9754 ctx
->sessionid
= current
->sessionid
;
9756 ctx
->sqo_task
= get_task_struct(current
);
9759 * This is just grabbed for accounting purposes. When a process exits,
9760 * the mm is exited and dropped before the files, hence we need to hang
9761 * on to this mm purely for the purposes of being able to unaccount
9762 * memory (locked/pinned vm). It's not used for anything else.
9764 mmgrab(current
->mm
);
9765 ctx
->mm_account
= current
->mm
;
9767 #ifdef CONFIG_BLK_CGROUP
9769 * The sq thread will belong to the original cgroup it was inited in.
9770 * If the cgroup goes offline (e.g. disabling the io controller), then
9771 * issued bios will be associated with the closest cgroup later in the
9775 ctx
->sqo_blkcg_css
= blkcg_css();
9776 ret
= css_tryget_online(ctx
->sqo_blkcg_css
);
9779 /* don't init against a dying cgroup, have the user try again */
9780 ctx
->sqo_blkcg_css
= NULL
;
9785 ret
= io_allocate_scq_urings(ctx
, p
);
9789 ret
= io_sq_offload_create(ctx
, p
);
9793 if (!(p
->flags
& IORING_SETUP_R_DISABLED
))
9794 io_sq_offload_start(ctx
);
9796 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9797 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9798 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9799 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9800 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9801 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9802 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9803 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9805 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9806 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9807 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9808 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9809 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9810 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9811 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9812 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9814 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9815 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9816 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9817 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
9818 IORING_FEAT_EXT_ARG
;
9820 if (copy_to_user(params
, p
, sizeof(*p
))) {
9825 file
= io_uring_get_file(ctx
);
9827 ret
= PTR_ERR(file
);
9832 * Install ring fd as the very last thing, so we don't risk someone
9833 * having closed it before we finish setup
9835 ret
= io_uring_install_fd(ctx
, file
);
9837 io_disable_sqo_submit(ctx
);
9838 /* fput will clean it up */
9843 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9846 io_disable_sqo_submit(ctx
);
9847 io_ring_ctx_wait_and_kill(ctx
);
9852 * Sets up an aio uring context, and returns the fd. Applications asks for a
9853 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9854 * params structure passed in.
9856 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9858 struct io_uring_params p
;
9861 if (copy_from_user(&p
, params
, sizeof(p
)))
9863 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9868 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9869 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9870 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9871 IORING_SETUP_R_DISABLED
))
9874 return io_uring_create(entries
, &p
, params
);
9877 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9878 struct io_uring_params __user
*, params
)
9880 return io_uring_setup(entries
, params
);
9883 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9885 struct io_uring_probe
*p
;
9889 size
= struct_size(p
, ops
, nr_args
);
9890 if (size
== SIZE_MAX
)
9892 p
= kzalloc(size
, GFP_KERNEL
);
9897 if (copy_from_user(p
, arg
, size
))
9900 if (memchr_inv(p
, 0, size
))
9903 p
->last_op
= IORING_OP_LAST
- 1;
9904 if (nr_args
> IORING_OP_LAST
)
9905 nr_args
= IORING_OP_LAST
;
9907 for (i
= 0; i
< nr_args
; i
++) {
9909 if (!io_op_defs
[i
].not_supported
)
9910 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9915 if (copy_to_user(arg
, p
, size
))
9922 static int io_register_personality(struct io_ring_ctx
*ctx
)
9924 struct io_identity
*id
;
9927 id
= kmalloc(sizeof(*id
), GFP_KERNEL
);
9931 io_init_identity(id
);
9932 id
->creds
= get_current_cred();
9934 ret
= idr_alloc_cyclic(&ctx
->personality_idr
, id
, 1, USHRT_MAX
, GFP_KERNEL
);
9936 put_cred(id
->creds
);
9942 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9943 unsigned int nr_args
)
9945 struct io_uring_restriction
*res
;
9949 /* Restrictions allowed only if rings started disabled */
9950 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9953 /* We allow only a single restrictions registration */
9954 if (ctx
->restrictions
.registered
)
9957 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9960 size
= array_size(nr_args
, sizeof(*res
));
9961 if (size
== SIZE_MAX
)
9964 res
= memdup_user(arg
, size
);
9966 return PTR_ERR(res
);
9970 for (i
= 0; i
< nr_args
; i
++) {
9971 switch (res
[i
].opcode
) {
9972 case IORING_RESTRICTION_REGISTER_OP
:
9973 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9978 __set_bit(res
[i
].register_op
,
9979 ctx
->restrictions
.register_op
);
9981 case IORING_RESTRICTION_SQE_OP
:
9982 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9987 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9989 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9990 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9992 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9993 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
10002 /* Reset all restrictions if an error happened */
10004 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
10006 ctx
->restrictions
.registered
= true;
10012 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
10014 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
10017 if (ctx
->restrictions
.registered
)
10018 ctx
->restricted
= 1;
10020 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
10022 io_sq_offload_start(ctx
);
10027 static bool io_register_op_must_quiesce(int op
)
10030 case IORING_UNREGISTER_FILES
:
10031 case IORING_REGISTER_FILES_UPDATE
:
10032 case IORING_REGISTER_PROBE
:
10033 case IORING_REGISTER_PERSONALITY
:
10034 case IORING_UNREGISTER_PERSONALITY
:
10041 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
10042 void __user
*arg
, unsigned nr_args
)
10043 __releases(ctx
->uring_lock
)
10044 __acquires(ctx
->uring_lock
)
10049 * We're inside the ring mutex, if the ref is already dying, then
10050 * someone else killed the ctx or is already going through
10051 * io_uring_register().
10053 if (percpu_ref_is_dying(&ctx
->refs
))
10056 if (io_register_op_must_quiesce(opcode
)) {
10057 percpu_ref_kill(&ctx
->refs
);
10060 * Drop uring mutex before waiting for references to exit. If
10061 * another thread is currently inside io_uring_enter() it might
10062 * need to grab the uring_lock to make progress. If we hold it
10063 * here across the drain wait, then we can deadlock. It's safe
10064 * to drop the mutex here, since no new references will come in
10065 * after we've killed the percpu ref.
10067 mutex_unlock(&ctx
->uring_lock
);
10069 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
10072 ret
= io_run_task_work_sig();
10077 mutex_lock(&ctx
->uring_lock
);
10080 percpu_ref_resurrect(&ctx
->refs
);
10085 if (ctx
->restricted
) {
10086 if (opcode
>= IORING_REGISTER_LAST
) {
10091 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
10098 case IORING_REGISTER_BUFFERS
:
10099 ret
= io_sqe_buffers_register(ctx
, arg
, nr_args
);
10101 case IORING_UNREGISTER_BUFFERS
:
10103 if (arg
|| nr_args
)
10105 ret
= io_sqe_buffers_unregister(ctx
);
10107 case IORING_REGISTER_FILES
:
10108 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
10110 case IORING_UNREGISTER_FILES
:
10112 if (arg
|| nr_args
)
10114 ret
= io_sqe_files_unregister(ctx
);
10116 case IORING_REGISTER_FILES_UPDATE
:
10117 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
10119 case IORING_REGISTER_EVENTFD
:
10120 case IORING_REGISTER_EVENTFD_ASYNC
:
10124 ret
= io_eventfd_register(ctx
, arg
);
10127 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
10128 ctx
->eventfd_async
= 1;
10130 ctx
->eventfd_async
= 0;
10132 case IORING_UNREGISTER_EVENTFD
:
10134 if (arg
|| nr_args
)
10136 ret
= io_eventfd_unregister(ctx
);
10138 case IORING_REGISTER_PROBE
:
10140 if (!arg
|| nr_args
> 256)
10142 ret
= io_probe(ctx
, arg
, nr_args
);
10144 case IORING_REGISTER_PERSONALITY
:
10146 if (arg
|| nr_args
)
10148 ret
= io_register_personality(ctx
);
10150 case IORING_UNREGISTER_PERSONALITY
:
10154 ret
= io_unregister_personality(ctx
, nr_args
);
10156 case IORING_REGISTER_ENABLE_RINGS
:
10158 if (arg
|| nr_args
)
10160 ret
= io_register_enable_rings(ctx
);
10162 case IORING_REGISTER_RESTRICTIONS
:
10163 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
10171 if (io_register_op_must_quiesce(opcode
)) {
10172 /* bring the ctx back to life */
10173 percpu_ref_reinit(&ctx
->refs
);
10175 reinit_completion(&ctx
->ref_comp
);
10180 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
10181 void __user
*, arg
, unsigned int, nr_args
)
10183 struct io_ring_ctx
*ctx
;
10192 if (f
.file
->f_op
!= &io_uring_fops
)
10195 ctx
= f
.file
->private_data
;
10197 mutex_lock(&ctx
->uring_lock
);
10198 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
10199 mutex_unlock(&ctx
->uring_lock
);
10200 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
10201 ctx
->cq_ev_fd
!= NULL
, ret
);
10207 static int __init
io_uring_init(void)
10209 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10210 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10211 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10214 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10215 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10216 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
10217 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
10218 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
10219 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
10220 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
10221 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
10222 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
10223 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
10224 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
10225 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
10226 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
10227 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
10228 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
10229 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
10230 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
10231 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
10232 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
10233 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
10234 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
10235 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
10236 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
10237 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
10238 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
10239 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
10240 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
10241 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
10242 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
10243 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
10244 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
10246 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
10247 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
10248 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
|
10252 __initcall(io_uring_init
);