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/blkdev.h>
61 #include <linux/bvec.h>
62 #include <linux/net.h>
64 #include <net/af_unix.h>
66 #include <linux/anon_inodes.h>
67 #include <linux/sched/mm.h>
68 #include <linux/uaccess.h>
69 #include <linux/nospec.h>
70 #include <linux/sizes.h>
71 #include <linux/hugetlb.h>
72 #include <linux/highmem.h>
73 #include <linux/namei.h>
74 #include <linux/fsnotify.h>
75 #include <linux/fadvise.h>
76 #include <linux/eventpoll.h>
77 #include <linux/splice.h>
78 #include <linux/task_work.h>
79 #include <linux/pagemap.h>
80 #include <linux/io_uring.h>
82 #define CREATE_TRACE_POINTS
83 #include <trace/events/io_uring.h>
85 #include <uapi/linux/io_uring.h>
90 #define IORING_MAX_ENTRIES 32768
91 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
94 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
96 #define IORING_FILE_TABLE_SHIFT 9
97 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
98 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
99 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
100 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
101 IORING_REGISTER_LAST + IORING_OP_LAST)
103 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
104 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
108 u32 head ____cacheline_aligned_in_smp
;
109 u32 tail ____cacheline_aligned_in_smp
;
113 * This data is shared with the application through the mmap at offsets
114 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
116 * The offsets to the member fields are published through struct
117 * io_sqring_offsets when calling io_uring_setup.
121 * Head and tail offsets into the ring; the offsets need to be
122 * masked to get valid indices.
124 * The kernel controls head of the sq ring and the tail of the cq ring,
125 * and the application controls tail of the sq ring and the head of the
128 struct io_uring sq
, cq
;
130 * Bitmasks to apply to head and tail offsets (constant, equals
133 u32 sq_ring_mask
, cq_ring_mask
;
134 /* Ring sizes (constant, power of 2) */
135 u32 sq_ring_entries
, cq_ring_entries
;
137 * Number of invalid entries dropped by the kernel due to
138 * invalid index stored in array
140 * Written by the kernel, shouldn't be modified by the
141 * application (i.e. get number of "new events" by comparing to
144 * After a new SQ head value was read by the application this
145 * counter includes all submissions that were dropped reaching
146 * the new SQ head (and possibly more).
152 * Written by the kernel, shouldn't be modified by the
155 * The application needs a full memory barrier before checking
156 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
162 * Written by the application, shouldn't be modified by the
167 * Number of completion events lost because the queue was full;
168 * this should be avoided by the application by making sure
169 * there are not more requests pending than there is space in
170 * the completion queue.
172 * Written by the kernel, shouldn't be modified by the
173 * application (i.e. get number of "new events" by comparing to
176 * As completion events come in out of order this counter is not
177 * ordered with any other data.
181 * Ring buffer of completion events.
183 * The kernel writes completion events fresh every time they are
184 * produced, so the application is allowed to modify pending
187 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
190 enum io_uring_cmd_flags
{
191 IO_URING_F_NONBLOCK
= 1,
192 IO_URING_F_COMPLETE_DEFER
= 2,
195 struct io_mapped_ubuf
{
198 struct bio_vec
*bvec
;
199 unsigned int nr_bvecs
;
200 unsigned long acct_pages
;
205 struct io_overflow_cqe
{
206 struct io_uring_cqe cqe
;
207 struct list_head list
;
210 struct io_fixed_file
{
211 /* file * with additional FFS_* flags */
212 unsigned long file_ptr
;
216 struct list_head list
;
223 struct io_file_table
{
224 /* two level table */
225 struct io_fixed_file
**files
;
228 struct io_rsrc_node
{
229 struct percpu_ref refs
;
230 struct list_head node
;
231 struct list_head rsrc_list
;
232 struct io_rsrc_data
*rsrc_data
;
233 struct llist_node llist
;
237 typedef void (rsrc_put_fn
)(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
);
239 struct io_rsrc_data
{
240 struct io_ring_ctx
*ctx
;
244 struct completion done
;
249 struct list_head list
;
255 struct io_restriction
{
256 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
257 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
258 u8 sqe_flags_allowed
;
259 u8 sqe_flags_required
;
264 IO_SQ_THREAD_SHOULD_STOP
= 0,
265 IO_SQ_THREAD_SHOULD_PARK
,
270 atomic_t park_pending
;
273 /* ctx's that are using this sqd */
274 struct list_head ctx_list
;
276 struct task_struct
*thread
;
277 struct wait_queue_head wait
;
279 unsigned sq_thread_idle
;
285 struct completion exited
;
286 struct callback_head
*park_task_work
;
289 #define IO_IOPOLL_BATCH 8
290 #define IO_COMPL_BATCH 32
291 #define IO_REQ_CACHE_SIZE 32
292 #define IO_REQ_ALLOC_BATCH 8
294 struct io_comp_state
{
295 struct io_kiocb
*reqs
[IO_COMPL_BATCH
];
297 unsigned int locked_free_nr
;
298 /* inline/task_work completion list, under ->uring_lock */
299 struct list_head free_list
;
300 /* IRQ completion list, under ->completion_lock */
301 struct list_head locked_free_list
;
304 struct io_submit_link
{
305 struct io_kiocb
*head
;
306 struct io_kiocb
*last
;
309 struct io_submit_state
{
310 struct blk_plug plug
;
311 struct io_submit_link link
;
314 * io_kiocb alloc cache
316 void *reqs
[IO_REQ_CACHE_SIZE
];
317 unsigned int free_reqs
;
322 * Batch completion logic
324 struct io_comp_state comp
;
327 * File reference cache
331 unsigned int file_refs
;
332 unsigned int ios_left
;
337 struct percpu_ref refs
;
338 } ____cacheline_aligned_in_smp
;
342 unsigned int compat
: 1;
343 unsigned int drain_next
: 1;
344 unsigned int eventfd_async
: 1;
345 unsigned int restricted
: 1;
348 * Ring buffer of indices into array of io_uring_sqe, which is
349 * mmapped by the application using the IORING_OFF_SQES offset.
351 * This indirection could e.g. be used to assign fixed
352 * io_uring_sqe entries to operations and only submit them to
353 * the queue when needed.
355 * The kernel modifies neither the indices array nor the entries
359 unsigned cached_sq_head
;
362 unsigned sq_thread_idle
;
363 unsigned cached_sq_dropped
;
364 unsigned cached_cq_overflow
;
365 unsigned long sq_check_overflow
;
367 /* hashed buffered write serialization */
368 struct io_wq_hash
*hash_map
;
370 struct list_head defer_list
;
371 struct list_head timeout_list
;
372 struct list_head cq_overflow_list
;
374 struct io_uring_sqe
*sq_sqes
;
375 } ____cacheline_aligned_in_smp
;
378 struct mutex uring_lock
;
379 wait_queue_head_t wait
;
380 } ____cacheline_aligned_in_smp
;
382 struct io_submit_state submit_state
;
384 struct io_rings
*rings
;
386 /* Only used for accounting purposes */
387 struct mm_struct
*mm_account
;
389 const struct cred
*sq_creds
; /* cred used for __io_sq_thread() */
390 struct io_sq_data
*sq_data
; /* if using sq thread polling */
392 struct wait_queue_head sqo_sq_wait
;
393 struct list_head sqd_list
;
396 * If used, fixed file set. Writers must ensure that ->refs is dead,
397 * readers must ensure that ->refs is alive as long as the file* is
398 * used. Only updated through io_uring_register(2).
400 struct io_rsrc_data
*file_data
;
401 struct io_file_table file_table
;
402 unsigned nr_user_files
;
404 /* if used, fixed mapped user buffers */
405 unsigned nr_user_bufs
;
406 struct io_mapped_ubuf
*user_bufs
;
408 struct user_struct
*user
;
410 struct completion ref_comp
;
412 #if defined(CONFIG_UNIX)
413 struct socket
*ring_sock
;
416 struct xarray io_buffers
;
418 struct xarray personalities
;
422 unsigned cached_cq_tail
;
425 atomic_t cq_timeouts
;
426 unsigned cq_last_tm_flush
;
427 unsigned long cq_check_overflow
;
428 struct wait_queue_head cq_wait
;
429 struct fasync_struct
*cq_fasync
;
430 struct eventfd_ctx
*cq_ev_fd
;
431 } ____cacheline_aligned_in_smp
;
434 spinlock_t completion_lock
;
437 * ->iopoll_list is protected by the ctx->uring_lock for
438 * io_uring instances that don't use IORING_SETUP_SQPOLL.
439 * For SQPOLL, only the single threaded io_sq_thread() will
440 * manipulate the list, hence no extra locking is needed there.
442 struct list_head iopoll_list
;
443 struct hlist_head
*cancel_hash
;
444 unsigned cancel_hash_bits
;
445 bool poll_multi_file
;
446 } ____cacheline_aligned_in_smp
;
448 struct delayed_work rsrc_put_work
;
449 struct llist_head rsrc_put_llist
;
450 struct list_head rsrc_ref_list
;
451 spinlock_t rsrc_ref_lock
;
452 struct io_rsrc_node
*rsrc_node
;
453 struct io_rsrc_node
*rsrc_backup_node
;
455 struct io_restriction restrictions
;
458 struct callback_head
*exit_task_work
;
460 /* Keep this last, we don't need it for the fast path */
461 struct work_struct exit_work
;
462 struct list_head tctx_list
;
465 struct io_uring_task
{
466 /* submission side */
468 struct wait_queue_head wait
;
469 const struct io_ring_ctx
*last
;
471 struct percpu_counter inflight
;
472 atomic_t inflight_tracked
;
475 spinlock_t task_lock
;
476 struct io_wq_work_list task_list
;
477 unsigned long task_state
;
478 struct callback_head task_work
;
482 * First field must be the file pointer in all the
483 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
485 struct io_poll_iocb
{
487 struct wait_queue_head
*head
;
491 struct wait_queue_entry wait
;
494 struct io_poll_update
{
500 bool update_user_data
;
508 struct io_timeout_data
{
509 struct io_kiocb
*req
;
510 struct hrtimer timer
;
511 struct timespec64 ts
;
512 enum hrtimer_mode mode
;
517 struct sockaddr __user
*addr
;
518 int __user
*addr_len
;
520 unsigned long nofile
;
540 struct list_head list
;
541 /* head of the link, used by linked timeouts only */
542 struct io_kiocb
*head
;
545 struct io_timeout_rem
{
550 struct timespec64 ts
;
555 /* NOTE: kiocb has the file as the first member, so don't do it here */
563 struct sockaddr __user
*addr
;
570 struct compat_msghdr __user
*umsg_compat
;
571 struct user_msghdr __user
*umsg
;
577 struct io_buffer
*kbuf
;
583 struct filename
*filename
;
585 unsigned long nofile
;
588 struct io_rsrc_update
{
614 struct epoll_event event
;
618 struct file
*file_out
;
619 struct file
*file_in
;
626 struct io_provide_buf
{
640 const char __user
*filename
;
641 struct statx __user
*buffer
;
653 struct filename
*oldpath
;
654 struct filename
*newpath
;
662 struct filename
*filename
;
665 struct io_completion
{
667 struct list_head list
;
671 struct io_async_connect
{
672 struct sockaddr_storage address
;
675 struct io_async_msghdr
{
676 struct iovec fast_iov
[UIO_FASTIOV
];
677 /* points to an allocated iov, if NULL we use fast_iov instead */
678 struct iovec
*free_iov
;
679 struct sockaddr __user
*uaddr
;
681 struct sockaddr_storage addr
;
685 struct iovec fast_iov
[UIO_FASTIOV
];
686 const struct iovec
*free_iovec
;
687 struct iov_iter iter
;
689 struct wait_page_queue wpq
;
693 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
694 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
695 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
696 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
697 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
698 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
704 REQ_F_LINK_TIMEOUT_BIT
,
705 REQ_F_NEED_CLEANUP_BIT
,
707 REQ_F_BUFFER_SELECTED_BIT
,
708 REQ_F_LTIMEOUT_ACTIVE_BIT
,
709 REQ_F_COMPLETE_INLINE_BIT
,
711 REQ_F_DONT_REISSUE_BIT
,
712 /* keep async read/write and isreg together and in order */
713 REQ_F_ASYNC_READ_BIT
,
714 REQ_F_ASYNC_WRITE_BIT
,
717 /* not a real bit, just to check we're not overflowing the space */
723 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
724 /* drain existing IO first */
725 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
727 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
728 /* doesn't sever on completion < 0 */
729 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
731 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
732 /* IOSQE_BUFFER_SELECT */
733 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
735 /* fail rest of links */
736 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
737 /* on inflight list, should be cancelled and waited on exit reliably */
738 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
739 /* read/write uses file position */
740 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
741 /* must not punt to workers */
742 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
743 /* has or had linked timeout */
744 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
746 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
747 /* already went through poll handler */
748 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
749 /* buffer already selected */
750 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
751 /* linked timeout is active, i.e. prepared by link's head */
752 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
753 /* completion is deferred through io_comp_state */
754 REQ_F_COMPLETE_INLINE
= BIT(REQ_F_COMPLETE_INLINE_BIT
),
755 /* caller should reissue async */
756 REQ_F_REISSUE
= BIT(REQ_F_REISSUE_BIT
),
757 /* don't attempt request reissue, see io_rw_reissue() */
758 REQ_F_DONT_REISSUE
= BIT(REQ_F_DONT_REISSUE_BIT
),
759 /* supports async reads */
760 REQ_F_ASYNC_READ
= BIT(REQ_F_ASYNC_READ_BIT
),
761 /* supports async writes */
762 REQ_F_ASYNC_WRITE
= BIT(REQ_F_ASYNC_WRITE_BIT
),
764 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
768 struct io_poll_iocb poll
;
769 struct io_poll_iocb
*double_poll
;
772 struct io_task_work
{
773 struct io_wq_work_node node
;
774 task_work_func_t func
;
778 * NOTE! Each of the iocb union members has the file pointer
779 * as the first entry in their struct definition. So you can
780 * access the file pointer through any of the sub-structs,
781 * or directly as just 'ki_filp' in this struct.
787 struct io_poll_iocb poll
;
788 struct io_poll_update poll_update
;
789 struct io_accept accept
;
791 struct io_cancel cancel
;
792 struct io_timeout timeout
;
793 struct io_timeout_rem timeout_rem
;
794 struct io_connect connect
;
795 struct io_sr_msg sr_msg
;
797 struct io_close close
;
798 struct io_rsrc_update rsrc_update
;
799 struct io_fadvise fadvise
;
800 struct io_madvise madvise
;
801 struct io_epoll epoll
;
802 struct io_splice splice
;
803 struct io_provide_buf pbuf
;
804 struct io_statx statx
;
805 struct io_shutdown shutdown
;
806 struct io_rename rename
;
807 struct io_unlink unlink
;
808 /* use only after cleaning per-op data, see io_clean_op() */
809 struct io_completion
compl;
812 /* opcode allocated if it needs to store data for async defer */
815 /* polled IO has completed */
821 struct io_ring_ctx
*ctx
;
824 struct task_struct
*task
;
827 struct io_kiocb
*link
;
828 struct percpu_ref
*fixed_rsrc_refs
;
830 /* used with ctx->iopoll_list with reads/writes */
831 struct list_head inflight_entry
;
833 struct io_task_work io_task_work
;
834 struct callback_head task_work
;
836 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
837 struct hlist_node hash_node
;
838 struct async_poll
*apoll
;
839 struct io_wq_work work
;
842 struct io_tctx_node
{
843 struct list_head ctx_node
;
844 struct task_struct
*task
;
845 struct io_ring_ctx
*ctx
;
848 struct io_defer_entry
{
849 struct list_head list
;
850 struct io_kiocb
*req
;
855 /* needs req->file assigned */
856 unsigned needs_file
: 1;
857 /* hash wq insertion if file is a regular file */
858 unsigned hash_reg_file
: 1;
859 /* unbound wq insertion if file is a non-regular file */
860 unsigned unbound_nonreg_file
: 1;
861 /* opcode is not supported by this kernel */
862 unsigned not_supported
: 1;
863 /* set if opcode supports polled "wait" */
865 unsigned pollout
: 1;
866 /* op supports buffer selection */
867 unsigned buffer_select
: 1;
868 /* do prep async if is going to be punted */
869 unsigned needs_async_setup
: 1;
870 /* should block plug */
872 /* size of async data needed, if any */
873 unsigned short async_size
;
876 static const struct io_op_def io_op_defs
[] = {
877 [IORING_OP_NOP
] = {},
878 [IORING_OP_READV
] = {
880 .unbound_nonreg_file
= 1,
883 .needs_async_setup
= 1,
885 .async_size
= sizeof(struct io_async_rw
),
887 [IORING_OP_WRITEV
] = {
890 .unbound_nonreg_file
= 1,
892 .needs_async_setup
= 1,
894 .async_size
= sizeof(struct io_async_rw
),
896 [IORING_OP_FSYNC
] = {
899 [IORING_OP_READ_FIXED
] = {
901 .unbound_nonreg_file
= 1,
904 .async_size
= sizeof(struct io_async_rw
),
906 [IORING_OP_WRITE_FIXED
] = {
909 .unbound_nonreg_file
= 1,
912 .async_size
= sizeof(struct io_async_rw
),
914 [IORING_OP_POLL_ADD
] = {
916 .unbound_nonreg_file
= 1,
918 [IORING_OP_POLL_REMOVE
] = {},
919 [IORING_OP_SYNC_FILE_RANGE
] = {
922 [IORING_OP_SENDMSG
] = {
924 .unbound_nonreg_file
= 1,
926 .needs_async_setup
= 1,
927 .async_size
= sizeof(struct io_async_msghdr
),
929 [IORING_OP_RECVMSG
] = {
931 .unbound_nonreg_file
= 1,
934 .needs_async_setup
= 1,
935 .async_size
= sizeof(struct io_async_msghdr
),
937 [IORING_OP_TIMEOUT
] = {
938 .async_size
= sizeof(struct io_timeout_data
),
940 [IORING_OP_TIMEOUT_REMOVE
] = {
941 /* used by timeout updates' prep() */
943 [IORING_OP_ACCEPT
] = {
945 .unbound_nonreg_file
= 1,
948 [IORING_OP_ASYNC_CANCEL
] = {},
949 [IORING_OP_LINK_TIMEOUT
] = {
950 .async_size
= sizeof(struct io_timeout_data
),
952 [IORING_OP_CONNECT
] = {
954 .unbound_nonreg_file
= 1,
956 .needs_async_setup
= 1,
957 .async_size
= sizeof(struct io_async_connect
),
959 [IORING_OP_FALLOCATE
] = {
962 [IORING_OP_OPENAT
] = {},
963 [IORING_OP_CLOSE
] = {},
964 [IORING_OP_FILES_UPDATE
] = {},
965 [IORING_OP_STATX
] = {},
968 .unbound_nonreg_file
= 1,
972 .async_size
= sizeof(struct io_async_rw
),
974 [IORING_OP_WRITE
] = {
976 .unbound_nonreg_file
= 1,
979 .async_size
= sizeof(struct io_async_rw
),
981 [IORING_OP_FADVISE
] = {
984 [IORING_OP_MADVISE
] = {},
987 .unbound_nonreg_file
= 1,
992 .unbound_nonreg_file
= 1,
996 [IORING_OP_OPENAT2
] = {
998 [IORING_OP_EPOLL_CTL
] = {
999 .unbound_nonreg_file
= 1,
1001 [IORING_OP_SPLICE
] = {
1004 .unbound_nonreg_file
= 1,
1006 [IORING_OP_PROVIDE_BUFFERS
] = {},
1007 [IORING_OP_REMOVE_BUFFERS
] = {},
1011 .unbound_nonreg_file
= 1,
1013 [IORING_OP_SHUTDOWN
] = {
1016 [IORING_OP_RENAMEAT
] = {},
1017 [IORING_OP_UNLINKAT
] = {},
1020 static bool io_disarm_next(struct io_kiocb
*req
);
1021 static void io_uring_del_task_file(unsigned long index
);
1022 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
1023 struct task_struct
*task
,
1024 struct files_struct
*files
);
1025 static void io_uring_cancel_sqpoll(struct io_ring_ctx
*ctx
);
1026 static struct io_rsrc_node
*io_rsrc_node_alloc(struct io_ring_ctx
*ctx
);
1028 static bool io_cqring_fill_event(struct io_kiocb
*req
, long res
, unsigned cflags
);
1029 static void io_put_req(struct io_kiocb
*req
);
1030 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
1031 static void io_dismantle_req(struct io_kiocb
*req
);
1032 static void io_put_task(struct task_struct
*task
, int nr
);
1033 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
1034 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1035 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
1036 struct io_uring_rsrc_update
*ip
,
1038 static void io_clean_op(struct io_kiocb
*req
);
1039 static struct file
*io_file_get(struct io_submit_state
*state
,
1040 struct io_kiocb
*req
, int fd
, bool fixed
);
1041 static void __io_queue_sqe(struct io_kiocb
*req
);
1042 static void io_rsrc_put_work(struct work_struct
*work
);
1044 static void io_req_task_queue(struct io_kiocb
*req
);
1045 static void io_submit_flush_completions(struct io_comp_state
*cs
,
1046 struct io_ring_ctx
*ctx
);
1047 static bool io_poll_remove_waitqs(struct io_kiocb
*req
);
1048 static int io_req_prep_async(struct io_kiocb
*req
);
1050 static struct kmem_cache
*req_cachep
;
1052 static const struct file_operations io_uring_fops
;
1054 struct sock
*io_uring_get_socket(struct file
*file
)
1056 #if defined(CONFIG_UNIX)
1057 if (file
->f_op
== &io_uring_fops
) {
1058 struct io_ring_ctx
*ctx
= file
->private_data
;
1060 return ctx
->ring_sock
->sk
;
1065 EXPORT_SYMBOL(io_uring_get_socket
);
1067 #define io_for_each_link(pos, head) \
1068 for (pos = (head); pos; pos = pos->link)
1070 static inline void io_req_set_rsrc_node(struct io_kiocb
*req
)
1072 struct io_ring_ctx
*ctx
= req
->ctx
;
1074 if (!req
->fixed_rsrc_refs
) {
1075 req
->fixed_rsrc_refs
= &ctx
->rsrc_node
->refs
;
1076 percpu_ref_get(req
->fixed_rsrc_refs
);
1080 static void io_refs_resurrect(struct percpu_ref
*ref
, struct completion
*compl)
1082 bool got
= percpu_ref_tryget(ref
);
1084 /* already at zero, wait for ->release() */
1086 wait_for_completion(compl);
1087 percpu_ref_resurrect(ref
);
1089 percpu_ref_put(ref
);
1092 static bool io_match_task(struct io_kiocb
*head
,
1093 struct task_struct
*task
,
1094 struct files_struct
*files
)
1096 struct io_kiocb
*req
;
1098 if (task
&& head
->task
!= task
)
1103 io_for_each_link(req
, head
) {
1104 if (req
->flags
& REQ_F_INFLIGHT
)
1110 static inline void req_set_fail_links(struct io_kiocb
*req
)
1112 if (req
->flags
& REQ_F_LINK
)
1113 req
->flags
|= REQ_F_FAIL_LINK
;
1116 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1118 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1120 complete(&ctx
->ref_comp
);
1123 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1125 return !req
->timeout
.off
;
1128 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1130 struct io_ring_ctx
*ctx
;
1133 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1138 * Use 5 bits less than the max cq entries, that should give us around
1139 * 32 entries per hash list if totally full and uniformly spread.
1141 hash_bits
= ilog2(p
->cq_entries
);
1145 ctx
->cancel_hash_bits
= hash_bits
;
1146 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1148 if (!ctx
->cancel_hash
)
1150 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1152 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1153 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1156 ctx
->flags
= p
->flags
;
1157 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1158 INIT_LIST_HEAD(&ctx
->sqd_list
);
1159 init_waitqueue_head(&ctx
->cq_wait
);
1160 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1161 init_completion(&ctx
->ref_comp
);
1162 xa_init_flags(&ctx
->io_buffers
, XA_FLAGS_ALLOC1
);
1163 xa_init_flags(&ctx
->personalities
, XA_FLAGS_ALLOC1
);
1164 mutex_init(&ctx
->uring_lock
);
1165 init_waitqueue_head(&ctx
->wait
);
1166 spin_lock_init(&ctx
->completion_lock
);
1167 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1168 INIT_LIST_HEAD(&ctx
->defer_list
);
1169 INIT_LIST_HEAD(&ctx
->timeout_list
);
1170 spin_lock_init(&ctx
->rsrc_ref_lock
);
1171 INIT_LIST_HEAD(&ctx
->rsrc_ref_list
);
1172 INIT_DELAYED_WORK(&ctx
->rsrc_put_work
, io_rsrc_put_work
);
1173 init_llist_head(&ctx
->rsrc_put_llist
);
1174 INIT_LIST_HEAD(&ctx
->tctx_list
);
1175 INIT_LIST_HEAD(&ctx
->submit_state
.comp
.free_list
);
1176 INIT_LIST_HEAD(&ctx
->submit_state
.comp
.locked_free_list
);
1179 kfree(ctx
->cancel_hash
);
1184 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1186 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1187 struct io_ring_ctx
*ctx
= req
->ctx
;
1189 return seq
!= ctx
->cached_cq_tail
1190 + READ_ONCE(ctx
->cached_cq_overflow
);
1196 static void io_req_track_inflight(struct io_kiocb
*req
)
1198 if (!(req
->flags
& REQ_F_INFLIGHT
)) {
1199 req
->flags
|= REQ_F_INFLIGHT
;
1200 atomic_inc(¤t
->io_uring
->inflight_tracked
);
1204 static void io_prep_async_work(struct io_kiocb
*req
)
1206 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1207 struct io_ring_ctx
*ctx
= req
->ctx
;
1209 if (!req
->work
.creds
)
1210 req
->work
.creds
= get_current_cred();
1212 req
->work
.list
.next
= NULL
;
1213 req
->work
.flags
= 0;
1214 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1215 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1217 if (req
->flags
& REQ_F_ISREG
) {
1218 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1219 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1220 } else if (!req
->file
|| !S_ISBLK(file_inode(req
->file
)->i_mode
)) {
1221 if (def
->unbound_nonreg_file
)
1222 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1225 switch (req
->opcode
) {
1226 case IORING_OP_SPLICE
:
1228 if (!S_ISREG(file_inode(req
->splice
.file_in
)->i_mode
))
1229 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1234 static void io_prep_async_link(struct io_kiocb
*req
)
1236 struct io_kiocb
*cur
;
1238 io_for_each_link(cur
, req
)
1239 io_prep_async_work(cur
);
1242 static void io_queue_async_work(struct io_kiocb
*req
)
1244 struct io_ring_ctx
*ctx
= req
->ctx
;
1245 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1246 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1249 BUG_ON(!tctx
->io_wq
);
1251 /* init ->work of the whole link before punting */
1252 io_prep_async_link(req
);
1253 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1254 &req
->work
, req
->flags
);
1255 io_wq_enqueue(tctx
->io_wq
, &req
->work
);
1257 io_queue_linked_timeout(link
);
1260 static void io_kill_timeout(struct io_kiocb
*req
, int status
)
1261 __must_hold(&req
->ctx
->completion_lock
)
1263 struct io_timeout_data
*io
= req
->async_data
;
1265 if (hrtimer_try_to_cancel(&io
->timer
) != -1) {
1266 atomic_set(&req
->ctx
->cq_timeouts
,
1267 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1268 list_del_init(&req
->timeout
.list
);
1269 io_cqring_fill_event(req
, status
, 0);
1270 io_put_req_deferred(req
, 1);
1274 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1277 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1278 struct io_defer_entry
, list
);
1280 if (req_need_defer(de
->req
, de
->seq
))
1282 list_del_init(&de
->list
);
1283 io_req_task_queue(de
->req
);
1285 } while (!list_empty(&ctx
->defer_list
));
1288 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1292 if (list_empty(&ctx
->timeout_list
))
1295 seq
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
1298 u32 events_needed
, events_got
;
1299 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1300 struct io_kiocb
, timeout
.list
);
1302 if (io_is_timeout_noseq(req
))
1306 * Since seq can easily wrap around over time, subtract
1307 * the last seq at which timeouts were flushed before comparing.
1308 * Assuming not more than 2^31-1 events have happened since,
1309 * these subtractions won't have wrapped, so we can check if
1310 * target is in [last_seq, current_seq] by comparing the two.
1312 events_needed
= req
->timeout
.target_seq
- ctx
->cq_last_tm_flush
;
1313 events_got
= seq
- ctx
->cq_last_tm_flush
;
1314 if (events_got
< events_needed
)
1317 list_del_init(&req
->timeout
.list
);
1318 io_kill_timeout(req
, 0);
1319 } while (!list_empty(&ctx
->timeout_list
));
1321 ctx
->cq_last_tm_flush
= seq
;
1324 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1326 io_flush_timeouts(ctx
);
1328 /* order cqe stores with ring update */
1329 smp_store_release(&ctx
->rings
->cq
.tail
, ctx
->cached_cq_tail
);
1331 if (unlikely(!list_empty(&ctx
->defer_list
)))
1332 __io_queue_deferred(ctx
);
1335 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1337 struct io_rings
*r
= ctx
->rings
;
1339 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1342 static inline unsigned int __io_cqring_events(struct io_ring_ctx
*ctx
)
1344 return ctx
->cached_cq_tail
- READ_ONCE(ctx
->rings
->cq
.head
);
1347 static inline struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1349 struct io_rings
*rings
= ctx
->rings
;
1353 * writes to the cq entry need to come after reading head; the
1354 * control dependency is enough as we're using WRITE_ONCE to
1357 if (__io_cqring_events(ctx
) == rings
->cq_ring_entries
)
1360 tail
= ctx
->cached_cq_tail
++;
1361 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1364 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1366 if (likely(!ctx
->cq_ev_fd
))
1368 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1370 return !ctx
->eventfd_async
|| io_wq_current_is_worker();
1373 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1375 /* see waitqueue_active() comment */
1378 if (waitqueue_active(&ctx
->wait
))
1379 wake_up(&ctx
->wait
);
1380 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1381 wake_up(&ctx
->sq_data
->wait
);
1382 if (io_should_trigger_evfd(ctx
))
1383 eventfd_signal(ctx
->cq_ev_fd
, 1);
1384 if (waitqueue_active(&ctx
->cq_wait
)) {
1385 wake_up_interruptible(&ctx
->cq_wait
);
1386 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1390 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx
*ctx
)
1392 /* see waitqueue_active() comment */
1395 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1396 if (waitqueue_active(&ctx
->wait
))
1397 wake_up(&ctx
->wait
);
1399 if (io_should_trigger_evfd(ctx
))
1400 eventfd_signal(ctx
->cq_ev_fd
, 1);
1401 if (waitqueue_active(&ctx
->cq_wait
)) {
1402 wake_up_interruptible(&ctx
->cq_wait
);
1403 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1407 /* Returns true if there are no backlogged entries after the flush */
1408 static bool __io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1410 struct io_rings
*rings
= ctx
->rings
;
1411 unsigned long flags
;
1412 bool all_flushed
, posted
;
1414 if (!force
&& __io_cqring_events(ctx
) == rings
->cq_ring_entries
)
1418 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1419 while (!list_empty(&ctx
->cq_overflow_list
)) {
1420 struct io_uring_cqe
*cqe
= io_get_cqring(ctx
);
1421 struct io_overflow_cqe
*ocqe
;
1425 ocqe
= list_first_entry(&ctx
->cq_overflow_list
,
1426 struct io_overflow_cqe
, list
);
1428 memcpy(cqe
, &ocqe
->cqe
, sizeof(*cqe
));
1430 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1431 ++ctx
->cached_cq_overflow
);
1433 list_del(&ocqe
->list
);
1437 all_flushed
= list_empty(&ctx
->cq_overflow_list
);
1439 clear_bit(0, &ctx
->sq_check_overflow
);
1440 clear_bit(0, &ctx
->cq_check_overflow
);
1441 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1445 io_commit_cqring(ctx
);
1446 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1448 io_cqring_ev_posted(ctx
);
1452 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1456 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1457 /* iopoll syncs against uring_lock, not completion_lock */
1458 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1459 mutex_lock(&ctx
->uring_lock
);
1460 ret
= __io_cqring_overflow_flush(ctx
, force
);
1461 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1462 mutex_unlock(&ctx
->uring_lock
);
1469 * Shamelessly stolen from the mm implementation of page reference checking,
1470 * see commit f958d7b528b1 for details.
1472 #define req_ref_zero_or_close_to_overflow(req) \
1473 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1475 static inline bool req_ref_inc_not_zero(struct io_kiocb
*req
)
1477 return atomic_inc_not_zero(&req
->refs
);
1480 static inline bool req_ref_sub_and_test(struct io_kiocb
*req
, int refs
)
1482 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1483 return atomic_sub_and_test(refs
, &req
->refs
);
1486 static inline bool req_ref_put_and_test(struct io_kiocb
*req
)
1488 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1489 return atomic_dec_and_test(&req
->refs
);
1492 static inline void req_ref_put(struct io_kiocb
*req
)
1494 WARN_ON_ONCE(req_ref_put_and_test(req
));
1497 static inline void req_ref_get(struct io_kiocb
*req
)
1499 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1500 atomic_inc(&req
->refs
);
1503 static bool io_cqring_event_overflow(struct io_kiocb
*req
, long res
,
1504 unsigned int cflags
)
1506 struct io_ring_ctx
*ctx
= req
->ctx
;
1507 struct io_overflow_cqe
*ocqe
;
1509 ocqe
= kmalloc(sizeof(*ocqe
), GFP_ATOMIC
| __GFP_ACCOUNT
);
1512 * If we're in ring overflow flush mode, or in task cancel mode,
1513 * or cannot allocate an overflow entry, then we need to drop it
1516 WRITE_ONCE(ctx
->rings
->cq_overflow
, ++ctx
->cached_cq_overflow
);
1519 if (list_empty(&ctx
->cq_overflow_list
)) {
1520 set_bit(0, &ctx
->sq_check_overflow
);
1521 set_bit(0, &ctx
->cq_check_overflow
);
1522 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1524 ocqe
->cqe
.user_data
= req
->user_data
;
1525 ocqe
->cqe
.res
= res
;
1526 ocqe
->cqe
.flags
= cflags
;
1527 list_add_tail(&ocqe
->list
, &ctx
->cq_overflow_list
);
1531 static inline bool __io_cqring_fill_event(struct io_kiocb
*req
, long res
,
1532 unsigned int cflags
)
1534 struct io_ring_ctx
*ctx
= req
->ctx
;
1535 struct io_uring_cqe
*cqe
;
1537 trace_io_uring_complete(ctx
, req
->user_data
, res
, cflags
);
1540 * If we can't get a cq entry, userspace overflowed the
1541 * submission (by quite a lot). Increment the overflow count in
1544 cqe
= io_get_cqring(ctx
);
1546 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1547 WRITE_ONCE(cqe
->res
, res
);
1548 WRITE_ONCE(cqe
->flags
, cflags
);
1551 return io_cqring_event_overflow(req
, res
, cflags
);
1554 /* not as hot to bloat with inlining */
1555 static noinline
bool io_cqring_fill_event(struct io_kiocb
*req
, long res
,
1556 unsigned int cflags
)
1558 return __io_cqring_fill_event(req
, res
, cflags
);
1561 static void io_req_complete_post(struct io_kiocb
*req
, long res
,
1562 unsigned int cflags
)
1564 struct io_ring_ctx
*ctx
= req
->ctx
;
1565 unsigned long flags
;
1567 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1568 __io_cqring_fill_event(req
, res
, cflags
);
1570 * If we're the last reference to this request, add to our locked
1573 if (req_ref_put_and_test(req
)) {
1574 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
1576 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
1577 if (req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_FAIL_LINK
))
1578 io_disarm_next(req
);
1580 io_req_task_queue(req
->link
);
1584 io_dismantle_req(req
);
1585 io_put_task(req
->task
, 1);
1586 list_add(&req
->compl.list
, &cs
->locked_free_list
);
1587 cs
->locked_free_nr
++;
1589 if (!percpu_ref_tryget(&ctx
->refs
))
1592 io_commit_cqring(ctx
);
1593 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1596 io_cqring_ev_posted(ctx
);
1597 percpu_ref_put(&ctx
->refs
);
1601 static inline bool io_req_needs_clean(struct io_kiocb
*req
)
1603 return req
->flags
& (REQ_F_BUFFER_SELECTED
| REQ_F_NEED_CLEANUP
|
1607 static void io_req_complete_state(struct io_kiocb
*req
, long res
,
1608 unsigned int cflags
)
1610 if (io_req_needs_clean(req
))
1613 req
->compl.cflags
= cflags
;
1614 req
->flags
|= REQ_F_COMPLETE_INLINE
;
1617 static inline void __io_req_complete(struct io_kiocb
*req
, unsigned issue_flags
,
1618 long res
, unsigned cflags
)
1620 if (issue_flags
& IO_URING_F_COMPLETE_DEFER
)
1621 io_req_complete_state(req
, res
, cflags
);
1623 io_req_complete_post(req
, res
, cflags
);
1626 static inline void io_req_complete(struct io_kiocb
*req
, long res
)
1628 __io_req_complete(req
, 0, res
, 0);
1631 static void io_req_complete_failed(struct io_kiocb
*req
, long res
)
1633 req_set_fail_links(req
);
1635 io_req_complete_post(req
, res
, 0);
1638 static void io_flush_cached_locked_reqs(struct io_ring_ctx
*ctx
,
1639 struct io_comp_state
*cs
)
1641 spin_lock_irq(&ctx
->completion_lock
);
1642 list_splice_init(&cs
->locked_free_list
, &cs
->free_list
);
1643 cs
->locked_free_nr
= 0;
1644 spin_unlock_irq(&ctx
->completion_lock
);
1647 /* Returns true IFF there are requests in the cache */
1648 static bool io_flush_cached_reqs(struct io_ring_ctx
*ctx
)
1650 struct io_submit_state
*state
= &ctx
->submit_state
;
1651 struct io_comp_state
*cs
= &state
->comp
;
1655 * If we have more than a batch's worth of requests in our IRQ side
1656 * locked cache, grab the lock and move them over to our submission
1659 if (READ_ONCE(cs
->locked_free_nr
) > IO_COMPL_BATCH
)
1660 io_flush_cached_locked_reqs(ctx
, cs
);
1662 nr
= state
->free_reqs
;
1663 while (!list_empty(&cs
->free_list
)) {
1664 struct io_kiocb
*req
= list_first_entry(&cs
->free_list
,
1665 struct io_kiocb
, compl.list
);
1667 list_del(&req
->compl.list
);
1668 state
->reqs
[nr
++] = req
;
1669 if (nr
== ARRAY_SIZE(state
->reqs
))
1673 state
->free_reqs
= nr
;
1677 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
)
1679 struct io_submit_state
*state
= &ctx
->submit_state
;
1681 BUILD_BUG_ON(IO_REQ_ALLOC_BATCH
> ARRAY_SIZE(state
->reqs
));
1683 if (!state
->free_reqs
) {
1684 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1687 if (io_flush_cached_reqs(ctx
))
1690 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, IO_REQ_ALLOC_BATCH
,
1694 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1695 * retry single alloc to be on the safe side.
1697 if (unlikely(ret
<= 0)) {
1698 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1699 if (!state
->reqs
[0])
1703 state
->free_reqs
= ret
;
1707 return state
->reqs
[state
->free_reqs
];
1710 static inline void io_put_file(struct file
*file
)
1716 static void io_dismantle_req(struct io_kiocb
*req
)
1718 unsigned int flags
= req
->flags
;
1720 if (!(flags
& REQ_F_FIXED_FILE
))
1721 io_put_file(req
->file
);
1722 if (io_req_needs_clean(req
) || (req
->flags
& REQ_F_INFLIGHT
)) {
1724 if (req
->flags
& REQ_F_INFLIGHT
) {
1725 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1727 atomic_dec(&tctx
->inflight_tracked
);
1728 req
->flags
&= ~REQ_F_INFLIGHT
;
1731 if (req
->fixed_rsrc_refs
)
1732 percpu_ref_put(req
->fixed_rsrc_refs
);
1733 if (req
->async_data
)
1734 kfree(req
->async_data
);
1735 if (req
->work
.creds
) {
1736 put_cred(req
->work
.creds
);
1737 req
->work
.creds
= NULL
;
1741 /* must to be called somewhat shortly after putting a request */
1742 static inline void io_put_task(struct task_struct
*task
, int nr
)
1744 struct io_uring_task
*tctx
= task
->io_uring
;
1746 percpu_counter_sub(&tctx
->inflight
, nr
);
1747 if (unlikely(atomic_read(&tctx
->in_idle
)))
1748 wake_up(&tctx
->wait
);
1749 put_task_struct_many(task
, nr
);
1752 static void __io_free_req(struct io_kiocb
*req
)
1754 struct io_ring_ctx
*ctx
= req
->ctx
;
1756 io_dismantle_req(req
);
1757 io_put_task(req
->task
, 1);
1759 kmem_cache_free(req_cachep
, req
);
1760 percpu_ref_put(&ctx
->refs
);
1763 static inline void io_remove_next_linked(struct io_kiocb
*req
)
1765 struct io_kiocb
*nxt
= req
->link
;
1767 req
->link
= nxt
->link
;
1771 static bool io_kill_linked_timeout(struct io_kiocb
*req
)
1772 __must_hold(&req
->ctx
->completion_lock
)
1774 struct io_kiocb
*link
= req
->link
;
1777 * Can happen if a linked timeout fired and link had been like
1778 * req -> link t-out -> link t-out [-> ...]
1780 if (link
&& (link
->flags
& REQ_F_LTIMEOUT_ACTIVE
)) {
1781 struct io_timeout_data
*io
= link
->async_data
;
1783 io_remove_next_linked(req
);
1784 link
->timeout
.head
= NULL
;
1785 if (hrtimer_try_to_cancel(&io
->timer
) != -1) {
1786 io_cqring_fill_event(link
, -ECANCELED
, 0);
1787 io_put_req_deferred(link
, 1);
1794 static void io_fail_links(struct io_kiocb
*req
)
1795 __must_hold(&req
->ctx
->completion_lock
)
1797 struct io_kiocb
*nxt
, *link
= req
->link
;
1804 trace_io_uring_fail_link(req
, link
);
1805 io_cqring_fill_event(link
, -ECANCELED
, 0);
1806 io_put_req_deferred(link
, 2);
1811 static bool io_disarm_next(struct io_kiocb
*req
)
1812 __must_hold(&req
->ctx
->completion_lock
)
1814 bool posted
= false;
1816 if (likely(req
->flags
& REQ_F_LINK_TIMEOUT
))
1817 posted
= io_kill_linked_timeout(req
);
1818 if (unlikely((req
->flags
& REQ_F_FAIL_LINK
) &&
1819 !(req
->flags
& REQ_F_HARDLINK
))) {
1820 posted
|= (req
->link
!= NULL
);
1826 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
1828 struct io_kiocb
*nxt
;
1831 * If LINK is set, we have dependent requests in this chain. If we
1832 * didn't fail this request, queue the first one up, moving any other
1833 * dependencies to the next request. In case of failure, fail the rest
1836 if (req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_FAIL_LINK
)) {
1837 struct io_ring_ctx
*ctx
= req
->ctx
;
1838 unsigned long flags
;
1841 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1842 posted
= io_disarm_next(req
);
1844 io_commit_cqring(req
->ctx
);
1845 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1847 io_cqring_ev_posted(ctx
);
1854 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
1856 if (likely(!(req
->flags
& (REQ_F_LINK
|REQ_F_HARDLINK
))))
1858 return __io_req_find_next(req
);
1861 static void ctx_flush_and_put(struct io_ring_ctx
*ctx
)
1865 if (ctx
->submit_state
.comp
.nr
) {
1866 mutex_lock(&ctx
->uring_lock
);
1867 io_submit_flush_completions(&ctx
->submit_state
.comp
, ctx
);
1868 mutex_unlock(&ctx
->uring_lock
);
1870 percpu_ref_put(&ctx
->refs
);
1873 static bool __tctx_task_work(struct io_uring_task
*tctx
)
1875 struct io_ring_ctx
*ctx
= NULL
;
1876 struct io_wq_work_list list
;
1877 struct io_wq_work_node
*node
;
1879 if (wq_list_empty(&tctx
->task_list
))
1882 spin_lock_irq(&tctx
->task_lock
);
1883 list
= tctx
->task_list
;
1884 INIT_WQ_LIST(&tctx
->task_list
);
1885 spin_unlock_irq(&tctx
->task_lock
);
1889 struct io_wq_work_node
*next
= node
->next
;
1890 struct io_kiocb
*req
;
1892 req
= container_of(node
, struct io_kiocb
, io_task_work
.node
);
1893 if (req
->ctx
!= ctx
) {
1894 ctx_flush_and_put(ctx
);
1896 percpu_ref_get(&ctx
->refs
);
1899 req
->task_work
.func(&req
->task_work
);
1903 ctx_flush_and_put(ctx
);
1904 return list
.first
!= NULL
;
1907 static void tctx_task_work(struct callback_head
*cb
)
1909 struct io_uring_task
*tctx
= container_of(cb
, struct io_uring_task
, task_work
);
1911 clear_bit(0, &tctx
->task_state
);
1913 while (__tctx_task_work(tctx
))
1917 static int io_req_task_work_add(struct io_kiocb
*req
)
1919 struct task_struct
*tsk
= req
->task
;
1920 struct io_uring_task
*tctx
= tsk
->io_uring
;
1921 enum task_work_notify_mode notify
;
1922 struct io_wq_work_node
*node
, *prev
;
1923 unsigned long flags
;
1926 if (unlikely(tsk
->flags
& PF_EXITING
))
1929 WARN_ON_ONCE(!tctx
);
1931 spin_lock_irqsave(&tctx
->task_lock
, flags
);
1932 wq_list_add_tail(&req
->io_task_work
.node
, &tctx
->task_list
);
1933 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
1935 /* task_work already pending, we're done */
1936 if (test_bit(0, &tctx
->task_state
) ||
1937 test_and_set_bit(0, &tctx
->task_state
))
1941 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
1942 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
1943 * processing task_work. There's no reliable way to tell if TWA_RESUME
1946 notify
= (req
->ctx
->flags
& IORING_SETUP_SQPOLL
) ? TWA_NONE
: TWA_SIGNAL
;
1948 if (!task_work_add(tsk
, &tctx
->task_work
, notify
)) {
1949 wake_up_process(tsk
);
1954 * Slow path - we failed, find and delete work. if the work is not
1955 * in the list, it got run and we're fine.
1957 spin_lock_irqsave(&tctx
->task_lock
, flags
);
1958 wq_list_for_each(node
, prev
, &tctx
->task_list
) {
1959 if (&req
->io_task_work
.node
== node
) {
1960 wq_list_del(&tctx
->task_list
, node
, prev
);
1965 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
1966 clear_bit(0, &tctx
->task_state
);
1970 static bool io_run_task_work_head(struct callback_head
**work_head
)
1972 struct callback_head
*work
, *next
;
1973 bool executed
= false;
1976 work
= xchg(work_head
, NULL
);
1992 static void io_task_work_add_head(struct callback_head
**work_head
,
1993 struct callback_head
*task_work
)
1995 struct callback_head
*head
;
1998 head
= READ_ONCE(*work_head
);
1999 task_work
->next
= head
;
2000 } while (cmpxchg(work_head
, head
, task_work
) != head
);
2003 static void io_req_task_work_add_fallback(struct io_kiocb
*req
,
2004 task_work_func_t cb
)
2006 init_task_work(&req
->task_work
, cb
);
2007 io_task_work_add_head(&req
->ctx
->exit_task_work
, &req
->task_work
);
2010 static void io_req_task_cancel(struct callback_head
*cb
)
2012 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2013 struct io_ring_ctx
*ctx
= req
->ctx
;
2015 /* ctx is guaranteed to stay alive while we hold uring_lock */
2016 mutex_lock(&ctx
->uring_lock
);
2017 io_req_complete_failed(req
, req
->result
);
2018 mutex_unlock(&ctx
->uring_lock
);
2021 static void __io_req_task_submit(struct io_kiocb
*req
)
2023 struct io_ring_ctx
*ctx
= req
->ctx
;
2025 /* ctx stays valid until unlock, even if we drop all ours ctx->refs */
2026 mutex_lock(&ctx
->uring_lock
);
2027 if (!(current
->flags
& PF_EXITING
) && !current
->in_execve
)
2028 __io_queue_sqe(req
);
2030 io_req_complete_failed(req
, -EFAULT
);
2031 mutex_unlock(&ctx
->uring_lock
);
2034 static void io_req_task_submit(struct callback_head
*cb
)
2036 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2038 __io_req_task_submit(req
);
2041 static void io_req_task_queue_fail(struct io_kiocb
*req
, int ret
)
2044 req
->task_work
.func
= io_req_task_cancel
;
2046 if (unlikely(io_req_task_work_add(req
)))
2047 io_req_task_work_add_fallback(req
, io_req_task_cancel
);
2050 static void io_req_task_queue(struct io_kiocb
*req
)
2052 req
->task_work
.func
= io_req_task_submit
;
2054 if (unlikely(io_req_task_work_add(req
)))
2055 io_req_task_queue_fail(req
, -ECANCELED
);
2058 static inline void io_queue_next(struct io_kiocb
*req
)
2060 struct io_kiocb
*nxt
= io_req_find_next(req
);
2063 io_req_task_queue(nxt
);
2066 static void io_free_req(struct io_kiocb
*req
)
2073 struct task_struct
*task
;
2078 static inline void io_init_req_batch(struct req_batch
*rb
)
2085 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2086 struct req_batch
*rb
)
2089 io_put_task(rb
->task
, rb
->task_refs
);
2091 percpu_ref_put_many(&ctx
->refs
, rb
->ctx_refs
);
2094 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
,
2095 struct io_submit_state
*state
)
2098 io_dismantle_req(req
);
2100 if (req
->task
!= rb
->task
) {
2102 io_put_task(rb
->task
, rb
->task_refs
);
2103 rb
->task
= req
->task
;
2109 if (state
->free_reqs
!= ARRAY_SIZE(state
->reqs
))
2110 state
->reqs
[state
->free_reqs
++] = req
;
2112 list_add(&req
->compl.list
, &state
->comp
.free_list
);
2115 static void io_submit_flush_completions(struct io_comp_state
*cs
,
2116 struct io_ring_ctx
*ctx
)
2119 struct io_kiocb
*req
;
2120 struct req_batch rb
;
2122 io_init_req_batch(&rb
);
2123 spin_lock_irq(&ctx
->completion_lock
);
2124 for (i
= 0; i
< nr
; i
++) {
2126 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
2128 io_commit_cqring(ctx
);
2129 spin_unlock_irq(&ctx
->completion_lock
);
2131 io_cqring_ev_posted(ctx
);
2132 for (i
= 0; i
< nr
; i
++) {
2135 /* submission and completion refs */
2136 if (req_ref_sub_and_test(req
, 2))
2137 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2140 io_req_free_batch_finish(ctx
, &rb
);
2145 * Drop reference to request, return next in chain (if there is one) if this
2146 * was the last reference to this request.
2148 static inline struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2150 struct io_kiocb
*nxt
= NULL
;
2152 if (req_ref_put_and_test(req
)) {
2153 nxt
= io_req_find_next(req
);
2159 static inline void io_put_req(struct io_kiocb
*req
)
2161 if (req_ref_put_and_test(req
))
2165 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2167 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2172 static void io_free_req_deferred(struct io_kiocb
*req
)
2174 req
->task_work
.func
= io_put_req_deferred_cb
;
2175 if (unlikely(io_req_task_work_add(req
)))
2176 io_req_task_work_add_fallback(req
, io_put_req_deferred_cb
);
2179 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2181 if (req_ref_sub_and_test(req
, refs
))
2182 io_free_req_deferred(req
);
2185 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
)
2187 /* See comment at the top of this file */
2189 return __io_cqring_events(ctx
);
2192 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2194 struct io_rings
*rings
= ctx
->rings
;
2196 /* make sure SQ entry isn't read before tail */
2197 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2200 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2202 unsigned int cflags
;
2204 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2205 cflags
|= IORING_CQE_F_BUFFER
;
2206 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2211 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2213 struct io_buffer
*kbuf
;
2215 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2216 return io_put_kbuf(req
, kbuf
);
2219 static inline bool io_run_task_work(void)
2222 * Not safe to run on exiting task, and the task_work handling will
2223 * not add work to such a task.
2225 if (unlikely(current
->flags
& PF_EXITING
))
2227 if (current
->task_works
) {
2228 __set_current_state(TASK_RUNNING
);
2237 * Find and free completed poll iocbs
2239 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2240 struct list_head
*done
)
2242 struct req_batch rb
;
2243 struct io_kiocb
*req
;
2245 /* order with ->result store in io_complete_rw_iopoll() */
2248 io_init_req_batch(&rb
);
2249 while (!list_empty(done
)) {
2252 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2253 list_del(&req
->inflight_entry
);
2255 if (READ_ONCE(req
->result
) == -EAGAIN
&&
2256 !(req
->flags
& REQ_F_DONT_REISSUE
)) {
2257 req
->iopoll_completed
= 0;
2259 io_queue_async_work(req
);
2263 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2264 cflags
= io_put_rw_kbuf(req
);
2266 __io_cqring_fill_event(req
, req
->result
, cflags
);
2269 if (req_ref_put_and_test(req
))
2270 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2273 io_commit_cqring(ctx
);
2274 io_cqring_ev_posted_iopoll(ctx
);
2275 io_req_free_batch_finish(ctx
, &rb
);
2278 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2281 struct io_kiocb
*req
, *tmp
;
2287 * Only spin for completions if we don't have multiple devices hanging
2288 * off our complete list, and we're under the requested amount.
2290 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2293 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2294 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2297 * Move completed and retryable entries to our local lists.
2298 * If we find a request that requires polling, break out
2299 * and complete those lists first, if we have entries there.
2301 if (READ_ONCE(req
->iopoll_completed
)) {
2302 list_move_tail(&req
->inflight_entry
, &done
);
2305 if (!list_empty(&done
))
2308 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2312 /* iopoll may have completed current req */
2313 if (READ_ONCE(req
->iopoll_completed
))
2314 list_move_tail(&req
->inflight_entry
, &done
);
2321 if (!list_empty(&done
))
2322 io_iopoll_complete(ctx
, nr_events
, &done
);
2328 * We can't just wait for polled events to come to us, we have to actively
2329 * find and complete them.
2331 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2333 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2336 mutex_lock(&ctx
->uring_lock
);
2337 while (!list_empty(&ctx
->iopoll_list
)) {
2338 unsigned int nr_events
= 0;
2340 io_do_iopoll(ctx
, &nr_events
, 0);
2342 /* let it sleep and repeat later if can't complete a request */
2346 * Ensure we allow local-to-the-cpu processing to take place,
2347 * in this case we need to ensure that we reap all events.
2348 * Also let task_work, etc. to progress by releasing the mutex
2350 if (need_resched()) {
2351 mutex_unlock(&ctx
->uring_lock
);
2353 mutex_lock(&ctx
->uring_lock
);
2356 mutex_unlock(&ctx
->uring_lock
);
2359 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2361 unsigned int nr_events
= 0;
2365 * We disallow the app entering submit/complete with polling, but we
2366 * still need to lock the ring to prevent racing with polled issue
2367 * that got punted to a workqueue.
2369 mutex_lock(&ctx
->uring_lock
);
2371 * Don't enter poll loop if we already have events pending.
2372 * If we do, we can potentially be spinning for commands that
2373 * already triggered a CQE (eg in error).
2375 if (test_bit(0, &ctx
->cq_check_overflow
))
2376 __io_cqring_overflow_flush(ctx
, false);
2377 if (io_cqring_events(ctx
))
2381 * If a submit got punted to a workqueue, we can have the
2382 * application entering polling for a command before it gets
2383 * issued. That app will hold the uring_lock for the duration
2384 * of the poll right here, so we need to take a breather every
2385 * now and then to ensure that the issue has a chance to add
2386 * the poll to the issued list. Otherwise we can spin here
2387 * forever, while the workqueue is stuck trying to acquire the
2390 if (list_empty(&ctx
->iopoll_list
)) {
2391 mutex_unlock(&ctx
->uring_lock
);
2393 mutex_lock(&ctx
->uring_lock
);
2395 if (list_empty(&ctx
->iopoll_list
))
2398 ret
= io_do_iopoll(ctx
, &nr_events
, min
);
2399 } while (!ret
&& nr_events
< min
&& !need_resched());
2401 mutex_unlock(&ctx
->uring_lock
);
2405 static void kiocb_end_write(struct io_kiocb
*req
)
2408 * Tell lockdep we inherited freeze protection from submission
2411 if (req
->flags
& REQ_F_ISREG
) {
2412 struct super_block
*sb
= file_inode(req
->file
)->i_sb
;
2414 __sb_writers_acquired(sb
, SB_FREEZE_WRITE
);
2420 static bool io_resubmit_prep(struct io_kiocb
*req
)
2422 struct io_async_rw
*rw
= req
->async_data
;
2425 return !io_req_prep_async(req
);
2426 /* may have left rw->iter inconsistent on -EIOCBQUEUED */
2427 iov_iter_revert(&rw
->iter
, req
->result
- iov_iter_count(&rw
->iter
));
2431 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2433 umode_t mode
= file_inode(req
->file
)->i_mode
;
2434 struct io_ring_ctx
*ctx
= req
->ctx
;
2436 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2438 if ((req
->flags
& REQ_F_NOWAIT
) || (io_wq_current_is_worker() &&
2439 !(ctx
->flags
& IORING_SETUP_IOPOLL
)))
2442 * If ref is dying, we might be running poll reap from the exit work.
2443 * Don't attempt to reissue from that path, just let it fail with
2446 if (percpu_ref_is_dying(&ctx
->refs
))
2451 static bool io_resubmit_prep(struct io_kiocb
*req
)
2455 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2461 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2462 unsigned int issue_flags
)
2466 if (req
->rw
.kiocb
.ki_flags
& IOCB_WRITE
)
2467 kiocb_end_write(req
);
2468 if (res
!= req
->result
) {
2469 if ((res
== -EAGAIN
|| res
== -EOPNOTSUPP
) &&
2470 io_rw_should_reissue(req
)) {
2471 req
->flags
|= REQ_F_REISSUE
;
2474 req_set_fail_links(req
);
2476 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2477 cflags
= io_put_rw_kbuf(req
);
2478 __io_req_complete(req
, issue_flags
, res
, cflags
);
2481 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2483 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2485 __io_complete_rw(req
, res
, res2
, 0);
2488 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2490 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2492 if (kiocb
->ki_flags
& IOCB_WRITE
)
2493 kiocb_end_write(req
);
2494 if (unlikely(res
!= req
->result
)) {
2495 if (!(res
== -EAGAIN
&& io_rw_should_reissue(req
) &&
2496 io_resubmit_prep(req
))) {
2497 req_set_fail_links(req
);
2498 req
->flags
|= REQ_F_DONT_REISSUE
;
2502 WRITE_ONCE(req
->result
, res
);
2503 /* order with io_iopoll_complete() checking ->result */
2505 WRITE_ONCE(req
->iopoll_completed
, 1);
2509 * After the iocb has been issued, it's safe to be found on the poll list.
2510 * Adding the kiocb to the list AFTER submission ensures that we don't
2511 * find it from a io_do_iopoll() thread before the issuer is done
2512 * accessing the kiocb cookie.
2514 static void io_iopoll_req_issued(struct io_kiocb
*req
, bool in_async
)
2516 struct io_ring_ctx
*ctx
= req
->ctx
;
2519 * Track whether we have multiple files in our lists. This will impact
2520 * how we do polling eventually, not spinning if we're on potentially
2521 * different devices.
2523 if (list_empty(&ctx
->iopoll_list
)) {
2524 ctx
->poll_multi_file
= false;
2525 } else if (!ctx
->poll_multi_file
) {
2526 struct io_kiocb
*list_req
;
2528 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2530 if (list_req
->file
!= req
->file
)
2531 ctx
->poll_multi_file
= true;
2535 * For fast devices, IO may have already completed. If it has, add
2536 * it to the front so we find it first.
2538 if (READ_ONCE(req
->iopoll_completed
))
2539 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2541 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2544 * If IORING_SETUP_SQPOLL is enabled, sqes are either handled in sq thread
2545 * task context or in io worker task context. If current task context is
2546 * sq thread, we don't need to check whether should wake up sq thread.
2548 if (in_async
&& (ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2549 wq_has_sleeper(&ctx
->sq_data
->wait
))
2550 wake_up(&ctx
->sq_data
->wait
);
2553 static inline void io_state_file_put(struct io_submit_state
*state
)
2555 if (state
->file_refs
) {
2556 fput_many(state
->file
, state
->file_refs
);
2557 state
->file_refs
= 0;
2562 * Get as many references to a file as we have IOs left in this submission,
2563 * assuming most submissions are for one file, or at least that each file
2564 * has more than one submission.
2566 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2571 if (state
->file_refs
) {
2572 if (state
->fd
== fd
) {
2576 io_state_file_put(state
);
2578 state
->file
= fget_many(fd
, state
->ios_left
);
2579 if (unlikely(!state
->file
))
2583 state
->file_refs
= state
->ios_left
- 1;
2587 static bool io_bdev_nowait(struct block_device
*bdev
)
2589 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2593 * If we tracked the file through the SCM inflight mechanism, we could support
2594 * any file. For now, just ensure that anything potentially problematic is done
2597 static bool __io_file_supports_async(struct file
*file
, int rw
)
2599 umode_t mode
= file_inode(file
)->i_mode
;
2601 if (S_ISBLK(mode
)) {
2602 if (IS_ENABLED(CONFIG_BLOCK
) &&
2603 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2607 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2609 if (S_ISREG(mode
)) {
2610 if (IS_ENABLED(CONFIG_BLOCK
) &&
2611 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2612 file
->f_op
!= &io_uring_fops
)
2617 /* any ->read/write should understand O_NONBLOCK */
2618 if (file
->f_flags
& O_NONBLOCK
)
2621 if (!(file
->f_mode
& FMODE_NOWAIT
))
2625 return file
->f_op
->read_iter
!= NULL
;
2627 return file
->f_op
->write_iter
!= NULL
;
2630 static bool io_file_supports_async(struct io_kiocb
*req
, int rw
)
2632 if (rw
== READ
&& (req
->flags
& REQ_F_ASYNC_READ
))
2634 else if (rw
== WRITE
&& (req
->flags
& REQ_F_ASYNC_WRITE
))
2637 return __io_file_supports_async(req
->file
, rw
);
2640 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2642 struct io_ring_ctx
*ctx
= req
->ctx
;
2643 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2644 struct file
*file
= req
->file
;
2648 if (!(req
->flags
& REQ_F_ISREG
) && S_ISREG(file_inode(file
)->i_mode
))
2649 req
->flags
|= REQ_F_ISREG
;
2651 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2652 if (kiocb
->ki_pos
== -1 && !(file
->f_mode
& FMODE_STREAM
)) {
2653 req
->flags
|= REQ_F_CUR_POS
;
2654 kiocb
->ki_pos
= file
->f_pos
;
2656 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2657 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2658 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2662 /* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
2663 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) || (file
->f_flags
& O_NONBLOCK
))
2664 req
->flags
|= REQ_F_NOWAIT
;
2666 ioprio
= READ_ONCE(sqe
->ioprio
);
2668 ret
= ioprio_check_cap(ioprio
);
2672 kiocb
->ki_ioprio
= ioprio
;
2674 kiocb
->ki_ioprio
= get_current_ioprio();
2676 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2677 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2678 !kiocb
->ki_filp
->f_op
->iopoll
)
2681 kiocb
->ki_flags
|= IOCB_HIPRI
;
2682 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2683 req
->iopoll_completed
= 0;
2685 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2687 kiocb
->ki_complete
= io_complete_rw
;
2690 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2691 req
->rw
.len
= READ_ONCE(sqe
->len
);
2692 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2696 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2702 case -ERESTARTNOINTR
:
2703 case -ERESTARTNOHAND
:
2704 case -ERESTART_RESTARTBLOCK
:
2706 * We can't just restart the syscall, since previously
2707 * submitted sqes may already be in progress. Just fail this
2713 kiocb
->ki_complete(kiocb
, ret
, 0);
2717 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2718 unsigned int issue_flags
)
2720 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2721 struct io_async_rw
*io
= req
->async_data
;
2722 bool check_reissue
= kiocb
->ki_complete
== io_complete_rw
;
2724 /* add previously done IO, if any */
2725 if (io
&& io
->bytes_done
> 0) {
2727 ret
= io
->bytes_done
;
2729 ret
+= io
->bytes_done
;
2732 if (req
->flags
& REQ_F_CUR_POS
)
2733 req
->file
->f_pos
= kiocb
->ki_pos
;
2734 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2735 __io_complete_rw(req
, ret
, 0, issue_flags
);
2737 io_rw_done(kiocb
, ret
);
2739 if (check_reissue
&& req
->flags
& REQ_F_REISSUE
) {
2740 req
->flags
&= ~REQ_F_REISSUE
;
2741 if (io_resubmit_prep(req
)) {
2743 io_queue_async_work(req
);
2747 req_set_fail_links(req
);
2748 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2749 cflags
= io_put_rw_kbuf(req
);
2750 __io_req_complete(req
, issue_flags
, ret
, cflags
);
2755 static int io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
)
2757 struct io_ring_ctx
*ctx
= req
->ctx
;
2758 size_t len
= req
->rw
.len
;
2759 struct io_mapped_ubuf
*imu
;
2760 u16 index
, buf_index
= req
->buf_index
;
2761 u64 buf_end
, buf_addr
= req
->rw
.addr
;
2764 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2766 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2767 imu
= &ctx
->user_bufs
[index
];
2768 buf_addr
= req
->rw
.addr
;
2770 if (unlikely(check_add_overflow(buf_addr
, (u64
)len
, &buf_end
)))
2772 /* not inside the mapped region */
2773 if (unlikely(buf_addr
< imu
->ubuf
|| buf_end
> imu
->ubuf_end
))
2777 * May not be a start of buffer, set size appropriately
2778 * and advance us to the beginning.
2780 offset
= buf_addr
- imu
->ubuf
;
2781 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2785 * Don't use iov_iter_advance() here, as it's really slow for
2786 * using the latter parts of a big fixed buffer - it iterates
2787 * over each segment manually. We can cheat a bit here, because
2790 * 1) it's a BVEC iter, we set it up
2791 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2792 * first and last bvec
2794 * So just find our index, and adjust the iterator afterwards.
2795 * If the offset is within the first bvec (or the whole first
2796 * bvec, just use iov_iter_advance(). This makes it easier
2797 * since we can just skip the first segment, which may not
2798 * be PAGE_SIZE aligned.
2800 const struct bio_vec
*bvec
= imu
->bvec
;
2802 if (offset
<= bvec
->bv_len
) {
2803 iov_iter_advance(iter
, offset
);
2805 unsigned long seg_skip
;
2807 /* skip first vec */
2808 offset
-= bvec
->bv_len
;
2809 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2811 iter
->bvec
= bvec
+ seg_skip
;
2812 iter
->nr_segs
-= seg_skip
;
2813 iter
->count
-= bvec
->bv_len
+ offset
;
2814 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2821 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2824 mutex_unlock(&ctx
->uring_lock
);
2827 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2830 * "Normal" inline submissions always hold the uring_lock, since we
2831 * grab it from the system call. Same is true for the SQPOLL offload.
2832 * The only exception is when we've detached the request and issue it
2833 * from an async worker thread, grab the lock for that case.
2836 mutex_lock(&ctx
->uring_lock
);
2839 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2840 int bgid
, struct io_buffer
*kbuf
,
2843 struct io_buffer
*head
;
2845 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2848 io_ring_submit_lock(req
->ctx
, needs_lock
);
2850 lockdep_assert_held(&req
->ctx
->uring_lock
);
2852 head
= xa_load(&req
->ctx
->io_buffers
, bgid
);
2854 if (!list_empty(&head
->list
)) {
2855 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2857 list_del(&kbuf
->list
);
2860 xa_erase(&req
->ctx
->io_buffers
, bgid
);
2862 if (*len
> kbuf
->len
)
2865 kbuf
= ERR_PTR(-ENOBUFS
);
2868 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2873 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2876 struct io_buffer
*kbuf
;
2879 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2880 bgid
= req
->buf_index
;
2881 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2884 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2885 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2886 return u64_to_user_ptr(kbuf
->addr
);
2889 #ifdef CONFIG_COMPAT
2890 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2893 struct compat_iovec __user
*uiov
;
2894 compat_ssize_t clen
;
2898 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2899 if (!access_ok(uiov
, sizeof(*uiov
)))
2901 if (__get_user(clen
, &uiov
->iov_len
))
2907 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2909 return PTR_ERR(buf
);
2910 iov
[0].iov_base
= buf
;
2911 iov
[0].iov_len
= (compat_size_t
) len
;
2916 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2919 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2923 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
2926 len
= iov
[0].iov_len
;
2929 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2931 return PTR_ERR(buf
);
2932 iov
[0].iov_base
= buf
;
2933 iov
[0].iov_len
= len
;
2937 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2940 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
2941 struct io_buffer
*kbuf
;
2943 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2944 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
2945 iov
[0].iov_len
= kbuf
->len
;
2948 if (req
->rw
.len
!= 1)
2951 #ifdef CONFIG_COMPAT
2952 if (req
->ctx
->compat
)
2953 return io_compat_import(req
, iov
, needs_lock
);
2956 return __io_iov_buffer_select(req
, iov
, needs_lock
);
2959 static int io_import_iovec(int rw
, struct io_kiocb
*req
, struct iovec
**iovec
,
2960 struct iov_iter
*iter
, bool needs_lock
)
2962 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
2963 size_t sqe_len
= req
->rw
.len
;
2964 u8 opcode
= req
->opcode
;
2967 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
2969 return io_import_fixed(req
, rw
, iter
);
2972 /* buffer index only valid with fixed read/write, or buffer select */
2973 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
2976 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
2977 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2978 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
2980 return PTR_ERR(buf
);
2981 req
->rw
.len
= sqe_len
;
2984 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
2989 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2990 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
2992 iov_iter_init(iter
, rw
, *iovec
, 1, (*iovec
)->iov_len
);
2997 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3001 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3003 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3007 * For files that don't have ->read_iter() and ->write_iter(), handle them
3008 * by looping over ->read() or ->write() manually.
3010 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3012 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3013 struct file
*file
= req
->file
;
3017 * Don't support polled IO through this interface, and we can't
3018 * support non-blocking either. For the latter, this just causes
3019 * the kiocb to be handled from an async context.
3021 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3023 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3026 while (iov_iter_count(iter
)) {
3030 if (!iov_iter_is_bvec(iter
)) {
3031 iovec
= iov_iter_iovec(iter
);
3033 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3034 iovec
.iov_len
= req
->rw
.len
;
3038 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3039 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3041 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3042 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3051 if (nr
!= iovec
.iov_len
)
3055 iov_iter_advance(iter
, nr
);
3061 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3062 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3064 struct io_async_rw
*rw
= req
->async_data
;
3066 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3067 rw
->free_iovec
= iovec
;
3069 /* can only be fixed buffers, no need to do anything */
3070 if (iov_iter_is_bvec(iter
))
3073 unsigned iov_off
= 0;
3075 rw
->iter
.iov
= rw
->fast_iov
;
3076 if (iter
->iov
!= fast_iov
) {
3077 iov_off
= iter
->iov
- fast_iov
;
3078 rw
->iter
.iov
+= iov_off
;
3080 if (rw
->fast_iov
!= fast_iov
)
3081 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3082 sizeof(struct iovec
) * iter
->nr_segs
);
3084 req
->flags
|= REQ_F_NEED_CLEANUP
;
3088 static inline int io_alloc_async_data(struct io_kiocb
*req
)
3090 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3091 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3092 return req
->async_data
== NULL
;
3095 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3096 const struct iovec
*fast_iov
,
3097 struct iov_iter
*iter
, bool force
)
3099 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_setup
)
3101 if (!req
->async_data
) {
3102 if (io_alloc_async_data(req
)) {
3107 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3112 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3114 struct io_async_rw
*iorw
= req
->async_data
;
3115 struct iovec
*iov
= iorw
->fast_iov
;
3118 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3119 if (unlikely(ret
< 0))
3122 iorw
->bytes_done
= 0;
3123 iorw
->free_iovec
= iov
;
3125 req
->flags
|= REQ_F_NEED_CLEANUP
;
3129 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3131 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3133 return io_prep_rw(req
, sqe
);
3137 * This is our waitqueue callback handler, registered through lock_page_async()
3138 * when we initially tried to do the IO with the iocb armed our waitqueue.
3139 * This gets called when the page is unlocked, and we generally expect that to
3140 * happen when the page IO is completed and the page is now uptodate. This will
3141 * queue a task_work based retry of the operation, attempting to copy the data
3142 * again. If the latter fails because the page was NOT uptodate, then we will
3143 * do a thread based blocking retry of the operation. That's the unexpected
3146 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3147 int sync
, void *arg
)
3149 struct wait_page_queue
*wpq
;
3150 struct io_kiocb
*req
= wait
->private;
3151 struct wait_page_key
*key
= arg
;
3153 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3155 if (!wake_page_match(wpq
, key
))
3158 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3159 list_del_init(&wait
->entry
);
3161 /* submit ref gets dropped, acquire a new one */
3163 io_req_task_queue(req
);
3168 * This controls whether a given IO request should be armed for async page
3169 * based retry. If we return false here, the request is handed to the async
3170 * worker threads for retry. If we're doing buffered reads on a regular file,
3171 * we prepare a private wait_page_queue entry and retry the operation. This
3172 * will either succeed because the page is now uptodate and unlocked, or it
3173 * will register a callback when the page is unlocked at IO completion. Through
3174 * that callback, io_uring uses task_work to setup a retry of the operation.
3175 * That retry will attempt the buffered read again. The retry will generally
3176 * succeed, or in rare cases where it fails, we then fall back to using the
3177 * async worker threads for a blocking retry.
3179 static bool io_rw_should_retry(struct io_kiocb
*req
)
3181 struct io_async_rw
*rw
= req
->async_data
;
3182 struct wait_page_queue
*wait
= &rw
->wpq
;
3183 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3185 /* never retry for NOWAIT, we just complete with -EAGAIN */
3186 if (req
->flags
& REQ_F_NOWAIT
)
3189 /* Only for buffered IO */
3190 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3194 * just use poll if we can, and don't attempt if the fs doesn't
3195 * support callback based unlocks
3197 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3200 wait
->wait
.func
= io_async_buf_func
;
3201 wait
->wait
.private = req
;
3202 wait
->wait
.flags
= 0;
3203 INIT_LIST_HEAD(&wait
->wait
.entry
);
3204 kiocb
->ki_flags
|= IOCB_WAITQ
;
3205 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3206 kiocb
->ki_waitq
= wait
;
3210 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3212 if (req
->file
->f_op
->read_iter
)
3213 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3214 else if (req
->file
->f_op
->read
)
3215 return loop_rw_iter(READ
, req
, iter
);
3220 static int io_read(struct io_kiocb
*req
, unsigned int issue_flags
)
3222 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3223 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3224 struct iov_iter __iter
, *iter
= &__iter
;
3225 struct io_async_rw
*rw
= req
->async_data
;
3226 ssize_t io_size
, ret
, ret2
;
3227 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3233 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3237 io_size
= iov_iter_count(iter
);
3238 req
->result
= io_size
;
3240 /* Ensure we clear previously set non-block flag */
3241 if (!force_nonblock
)
3242 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3244 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3246 /* If the file doesn't support async, just async punt */
3247 if (force_nonblock
&& !io_file_supports_async(req
, READ
)) {
3248 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3249 return ret
?: -EAGAIN
;
3252 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3253 if (unlikely(ret
)) {
3258 ret
= io_iter_do_read(req
, iter
);
3260 if (ret
== -EAGAIN
|| (req
->flags
& REQ_F_REISSUE
)) {
3261 req
->flags
&= ~REQ_F_REISSUE
;
3262 /* IOPOLL retry should happen for io-wq threads */
3263 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3265 /* no retry on NONBLOCK nor RWF_NOWAIT */
3266 if (req
->flags
& REQ_F_NOWAIT
)
3268 /* some cases will consume bytes even on error returns */
3269 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3271 } else if (ret
== -EIOCBQUEUED
) {
3273 } else if (ret
<= 0 || ret
== io_size
|| !force_nonblock
||
3274 (req
->flags
& REQ_F_NOWAIT
) || !(req
->flags
& REQ_F_ISREG
)) {
3275 /* read all, failed, already did sync or don't want to retry */
3279 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3284 rw
= req
->async_data
;
3285 /* now use our persistent iterator, if we aren't already */
3290 rw
->bytes_done
+= ret
;
3291 /* if we can retry, do so with the callbacks armed */
3292 if (!io_rw_should_retry(req
)) {
3293 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3298 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3299 * we get -EIOCBQUEUED, then we'll get a notification when the
3300 * desired page gets unlocked. We can also get a partial read
3301 * here, and if we do, then just retry at the new offset.
3303 ret
= io_iter_do_read(req
, iter
);
3304 if (ret
== -EIOCBQUEUED
)
3306 /* we got some bytes, but not all. retry. */
3307 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3308 } while (ret
> 0 && ret
< io_size
);
3310 kiocb_done(kiocb
, ret
, issue_flags
);
3312 /* it's faster to check here then delegate to kfree */
3318 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3320 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3322 return io_prep_rw(req
, sqe
);
3325 static int io_write(struct io_kiocb
*req
, unsigned int issue_flags
)
3327 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3328 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3329 struct iov_iter __iter
, *iter
= &__iter
;
3330 struct io_async_rw
*rw
= req
->async_data
;
3331 ssize_t ret
, ret2
, io_size
;
3332 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3338 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3342 io_size
= iov_iter_count(iter
);
3343 req
->result
= io_size
;
3345 /* Ensure we clear previously set non-block flag */
3346 if (!force_nonblock
)
3347 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3349 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3351 /* If the file doesn't support async, just async punt */
3352 if (force_nonblock
&& !io_file_supports_async(req
, WRITE
))
3355 /* file path doesn't support NOWAIT for non-direct_IO */
3356 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3357 (req
->flags
& REQ_F_ISREG
))
3360 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3365 * Open-code file_start_write here to grab freeze protection,
3366 * which will be released by another thread in
3367 * io_complete_rw(). Fool lockdep by telling it the lock got
3368 * released so that it doesn't complain about the held lock when
3369 * we return to userspace.
3371 if (req
->flags
& REQ_F_ISREG
) {
3372 sb_start_write(file_inode(req
->file
)->i_sb
);
3373 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3376 kiocb
->ki_flags
|= IOCB_WRITE
;
3378 if (req
->file
->f_op
->write_iter
)
3379 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3380 else if (req
->file
->f_op
->write
)
3381 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3385 if (req
->flags
& REQ_F_REISSUE
) {
3386 req
->flags
&= ~REQ_F_REISSUE
;
3391 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3392 * retry them without IOCB_NOWAIT.
3394 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3396 /* no retry on NONBLOCK nor RWF_NOWAIT */
3397 if (ret2
== -EAGAIN
&& (req
->flags
& REQ_F_NOWAIT
))
3399 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3400 /* IOPOLL retry should happen for io-wq threads */
3401 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3404 kiocb_done(kiocb
, ret2
, issue_flags
);
3407 /* some cases will consume bytes even on error returns */
3408 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3409 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3410 return ret
?: -EAGAIN
;
3413 /* it's reportedly faster than delegating the null check to kfree() */
3419 static int io_renameat_prep(struct io_kiocb
*req
,
3420 const struct io_uring_sqe
*sqe
)
3422 struct io_rename
*ren
= &req
->rename
;
3423 const char __user
*oldf
, *newf
;
3425 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3428 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3429 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3430 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3431 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3432 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3434 ren
->oldpath
= getname(oldf
);
3435 if (IS_ERR(ren
->oldpath
))
3436 return PTR_ERR(ren
->oldpath
);
3438 ren
->newpath
= getname(newf
);
3439 if (IS_ERR(ren
->newpath
)) {
3440 putname(ren
->oldpath
);
3441 return PTR_ERR(ren
->newpath
);
3444 req
->flags
|= REQ_F_NEED_CLEANUP
;
3448 static int io_renameat(struct io_kiocb
*req
, unsigned int issue_flags
)
3450 struct io_rename
*ren
= &req
->rename
;
3453 if (issue_flags
& IO_URING_F_NONBLOCK
)
3456 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3457 ren
->newpath
, ren
->flags
);
3459 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3461 req_set_fail_links(req
);
3462 io_req_complete(req
, ret
);
3466 static int io_unlinkat_prep(struct io_kiocb
*req
,
3467 const struct io_uring_sqe
*sqe
)
3469 struct io_unlink
*un
= &req
->unlink
;
3470 const char __user
*fname
;
3472 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3475 un
->dfd
= READ_ONCE(sqe
->fd
);
3477 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3478 if (un
->flags
& ~AT_REMOVEDIR
)
3481 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3482 un
->filename
= getname(fname
);
3483 if (IS_ERR(un
->filename
))
3484 return PTR_ERR(un
->filename
);
3486 req
->flags
|= REQ_F_NEED_CLEANUP
;
3490 static int io_unlinkat(struct io_kiocb
*req
, unsigned int issue_flags
)
3492 struct io_unlink
*un
= &req
->unlink
;
3495 if (issue_flags
& IO_URING_F_NONBLOCK
)
3498 if (un
->flags
& AT_REMOVEDIR
)
3499 ret
= do_rmdir(un
->dfd
, un
->filename
);
3501 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3503 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3505 req_set_fail_links(req
);
3506 io_req_complete(req
, ret
);
3510 static int io_shutdown_prep(struct io_kiocb
*req
,
3511 const struct io_uring_sqe
*sqe
)
3513 #if defined(CONFIG_NET)
3514 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3516 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3520 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3527 static int io_shutdown(struct io_kiocb
*req
, unsigned int issue_flags
)
3529 #if defined(CONFIG_NET)
3530 struct socket
*sock
;
3533 if (issue_flags
& IO_URING_F_NONBLOCK
)
3536 sock
= sock_from_file(req
->file
);
3537 if (unlikely(!sock
))
3540 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3542 req_set_fail_links(req
);
3543 io_req_complete(req
, ret
);
3550 static int __io_splice_prep(struct io_kiocb
*req
,
3551 const struct io_uring_sqe
*sqe
)
3553 struct io_splice
* sp
= &req
->splice
;
3554 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3556 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3560 sp
->len
= READ_ONCE(sqe
->len
);
3561 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3563 if (unlikely(sp
->flags
& ~valid_flags
))
3566 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3567 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3570 req
->flags
|= REQ_F_NEED_CLEANUP
;
3574 static int io_tee_prep(struct io_kiocb
*req
,
3575 const struct io_uring_sqe
*sqe
)
3577 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3579 return __io_splice_prep(req
, sqe
);
3582 static int io_tee(struct io_kiocb
*req
, unsigned int issue_flags
)
3584 struct io_splice
*sp
= &req
->splice
;
3585 struct file
*in
= sp
->file_in
;
3586 struct file
*out
= sp
->file_out
;
3587 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3590 if (issue_flags
& IO_URING_F_NONBLOCK
)
3593 ret
= do_tee(in
, out
, sp
->len
, flags
);
3595 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
3597 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3600 req_set_fail_links(req
);
3601 io_req_complete(req
, ret
);
3605 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3607 struct io_splice
* sp
= &req
->splice
;
3609 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3610 sp
->off_out
= READ_ONCE(sqe
->off
);
3611 return __io_splice_prep(req
, sqe
);
3614 static int io_splice(struct io_kiocb
*req
, unsigned int issue_flags
)
3616 struct io_splice
*sp
= &req
->splice
;
3617 struct file
*in
= sp
->file_in
;
3618 struct file
*out
= sp
->file_out
;
3619 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3620 loff_t
*poff_in
, *poff_out
;
3623 if (issue_flags
& IO_URING_F_NONBLOCK
)
3626 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3627 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3630 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3632 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
3634 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3637 req_set_fail_links(req
);
3638 io_req_complete(req
, ret
);
3643 * IORING_OP_NOP just posts a completion event, nothing else.
3645 static int io_nop(struct io_kiocb
*req
, unsigned int issue_flags
)
3647 struct io_ring_ctx
*ctx
= req
->ctx
;
3649 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3652 __io_req_complete(req
, issue_flags
, 0, 0);
3656 static int io_fsync_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3658 struct io_ring_ctx
*ctx
= req
->ctx
;
3663 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3665 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3668 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3669 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3672 req
->sync
.off
= READ_ONCE(sqe
->off
);
3673 req
->sync
.len
= READ_ONCE(sqe
->len
);
3677 static int io_fsync(struct io_kiocb
*req
, unsigned int issue_flags
)
3679 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3682 /* fsync always requires a blocking context */
3683 if (issue_flags
& IO_URING_F_NONBLOCK
)
3686 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3687 end
> 0 ? end
: LLONG_MAX
,
3688 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3690 req_set_fail_links(req
);
3691 io_req_complete(req
, ret
);
3695 static int io_fallocate_prep(struct io_kiocb
*req
,
3696 const struct io_uring_sqe
*sqe
)
3698 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3700 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3703 req
->sync
.off
= READ_ONCE(sqe
->off
);
3704 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3705 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3709 static int io_fallocate(struct io_kiocb
*req
, unsigned int issue_flags
)
3713 /* fallocate always requiring blocking context */
3714 if (issue_flags
& IO_URING_F_NONBLOCK
)
3716 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3719 req_set_fail_links(req
);
3720 io_req_complete(req
, ret
);
3724 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3726 const char __user
*fname
;
3729 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3731 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3734 /* open.how should be already initialised */
3735 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3736 req
->open
.how
.flags
|= O_LARGEFILE
;
3738 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3739 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3740 req
->open
.filename
= getname(fname
);
3741 if (IS_ERR(req
->open
.filename
)) {
3742 ret
= PTR_ERR(req
->open
.filename
);
3743 req
->open
.filename
= NULL
;
3746 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3747 req
->flags
|= REQ_F_NEED_CLEANUP
;
3751 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3755 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3757 mode
= READ_ONCE(sqe
->len
);
3758 flags
= READ_ONCE(sqe
->open_flags
);
3759 req
->open
.how
= build_open_how(flags
, mode
);
3760 return __io_openat_prep(req
, sqe
);
3763 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3765 struct open_how __user
*how
;
3769 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3771 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3772 len
= READ_ONCE(sqe
->len
);
3773 if (len
< OPEN_HOW_SIZE_VER0
)
3776 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3781 return __io_openat_prep(req
, sqe
);
3784 static int io_openat2(struct io_kiocb
*req
, unsigned int issue_flags
)
3786 struct open_flags op
;
3789 bool resolve_nonblock
;
3792 ret
= build_open_flags(&req
->open
.how
, &op
);
3795 nonblock_set
= op
.open_flag
& O_NONBLOCK
;
3796 resolve_nonblock
= req
->open
.how
.resolve
& RESOLVE_CACHED
;
3797 if (issue_flags
& IO_URING_F_NONBLOCK
) {
3799 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
3800 * it'll always -EAGAIN
3802 if (req
->open
.how
.flags
& (O_TRUNC
| O_CREAT
| O_TMPFILE
))
3804 op
.lookup_flags
|= LOOKUP_CACHED
;
3805 op
.open_flag
|= O_NONBLOCK
;
3808 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3812 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3813 /* only retry if RESOLVE_CACHED wasn't already set by application */
3814 if ((!resolve_nonblock
&& (issue_flags
& IO_URING_F_NONBLOCK
)) &&
3815 file
== ERR_PTR(-EAGAIN
)) {
3817 * We could hang on to this 'fd', but seems like marginal
3818 * gain for something that is now known to be a slower path.
3819 * So just put it, and we'll get a new one when we retry.
3827 ret
= PTR_ERR(file
);
3829 if ((issue_flags
& IO_URING_F_NONBLOCK
) && !nonblock_set
)
3830 file
->f_flags
&= ~O_NONBLOCK
;
3831 fsnotify_open(file
);
3832 fd_install(ret
, file
);
3835 putname(req
->open
.filename
);
3836 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3838 req_set_fail_links(req
);
3839 __io_req_complete(req
, issue_flags
, ret
, 0);
3843 static int io_openat(struct io_kiocb
*req
, unsigned int issue_flags
)
3845 return io_openat2(req
, issue_flags
);
3848 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3849 const struct io_uring_sqe
*sqe
)
3851 struct io_provide_buf
*p
= &req
->pbuf
;
3854 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3857 tmp
= READ_ONCE(sqe
->fd
);
3858 if (!tmp
|| tmp
> USHRT_MAX
)
3861 memset(p
, 0, sizeof(*p
));
3863 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3867 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3868 int bgid
, unsigned nbufs
)
3872 /* shouldn't happen */
3876 /* the head kbuf is the list itself */
3877 while (!list_empty(&buf
->list
)) {
3878 struct io_buffer
*nxt
;
3880 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3881 list_del(&nxt
->list
);
3888 xa_erase(&ctx
->io_buffers
, bgid
);
3893 static int io_remove_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
3895 struct io_provide_buf
*p
= &req
->pbuf
;
3896 struct io_ring_ctx
*ctx
= req
->ctx
;
3897 struct io_buffer
*head
;
3899 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3901 io_ring_submit_lock(ctx
, !force_nonblock
);
3903 lockdep_assert_held(&ctx
->uring_lock
);
3906 head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
3908 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3910 req_set_fail_links(req
);
3912 /* complete before unlock, IOPOLL may need the lock */
3913 __io_req_complete(req
, issue_flags
, ret
, 0);
3914 io_ring_submit_unlock(ctx
, !force_nonblock
);
3918 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3919 const struct io_uring_sqe
*sqe
)
3921 unsigned long size
, tmp_check
;
3922 struct io_provide_buf
*p
= &req
->pbuf
;
3925 if (sqe
->ioprio
|| sqe
->rw_flags
)
3928 tmp
= READ_ONCE(sqe
->fd
);
3929 if (!tmp
|| tmp
> USHRT_MAX
)
3932 p
->addr
= READ_ONCE(sqe
->addr
);
3933 p
->len
= READ_ONCE(sqe
->len
);
3935 if (check_mul_overflow((unsigned long)p
->len
, (unsigned long)p
->nbufs
,
3938 if (check_add_overflow((unsigned long)p
->addr
, size
, &tmp_check
))
3941 size
= (unsigned long)p
->len
* p
->nbufs
;
3942 if (!access_ok(u64_to_user_ptr(p
->addr
), size
))
3945 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3946 tmp
= READ_ONCE(sqe
->off
);
3947 if (tmp
> USHRT_MAX
)
3953 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3955 struct io_buffer
*buf
;
3956 u64 addr
= pbuf
->addr
;
3957 int i
, bid
= pbuf
->bid
;
3959 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3960 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3965 buf
->len
= pbuf
->len
;
3970 INIT_LIST_HEAD(&buf
->list
);
3973 list_add_tail(&buf
->list
, &(*head
)->list
);
3977 return i
? i
: -ENOMEM
;
3980 static int io_provide_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
3982 struct io_provide_buf
*p
= &req
->pbuf
;
3983 struct io_ring_ctx
*ctx
= req
->ctx
;
3984 struct io_buffer
*head
, *list
;
3986 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3988 io_ring_submit_lock(ctx
, !force_nonblock
);
3990 lockdep_assert_held(&ctx
->uring_lock
);
3992 list
= head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
3994 ret
= io_add_buffers(p
, &head
);
3995 if (ret
>= 0 && !list
) {
3996 ret
= xa_insert(&ctx
->io_buffers
, p
->bgid
, head
, GFP_KERNEL
);
3998 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4001 req_set_fail_links(req
);
4002 /* complete before unlock, IOPOLL may need the lock */
4003 __io_req_complete(req
, issue_flags
, ret
, 0);
4004 io_ring_submit_unlock(ctx
, !force_nonblock
);
4008 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4009 const struct io_uring_sqe
*sqe
)
4011 #if defined(CONFIG_EPOLL)
4012 if (sqe
->ioprio
|| sqe
->buf_index
)
4014 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4017 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4018 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4019 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4021 if (ep_op_has_event(req
->epoll
.op
)) {
4022 struct epoll_event __user
*ev
;
4024 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4025 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4035 static int io_epoll_ctl(struct io_kiocb
*req
, unsigned int issue_flags
)
4037 #if defined(CONFIG_EPOLL)
4038 struct io_epoll
*ie
= &req
->epoll
;
4040 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4042 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4043 if (force_nonblock
&& ret
== -EAGAIN
)
4047 req_set_fail_links(req
);
4048 __io_req_complete(req
, issue_flags
, ret
, 0);
4055 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4057 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4058 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4060 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4063 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4064 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4065 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4072 static int io_madvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4074 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4075 struct io_madvise
*ma
= &req
->madvise
;
4078 if (issue_flags
& IO_URING_F_NONBLOCK
)
4081 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4083 req_set_fail_links(req
);
4084 io_req_complete(req
, ret
);
4091 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4093 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4095 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4098 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4099 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4100 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4104 static int io_fadvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4106 struct io_fadvise
*fa
= &req
->fadvise
;
4109 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4110 switch (fa
->advice
) {
4111 case POSIX_FADV_NORMAL
:
4112 case POSIX_FADV_RANDOM
:
4113 case POSIX_FADV_SEQUENTIAL
:
4120 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4122 req_set_fail_links(req
);
4123 __io_req_complete(req
, issue_flags
, ret
, 0);
4127 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4129 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4131 if (sqe
->ioprio
|| sqe
->buf_index
)
4133 if (req
->flags
& REQ_F_FIXED_FILE
)
4136 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4137 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4138 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4139 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4140 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4145 static int io_statx(struct io_kiocb
*req
, unsigned int issue_flags
)
4147 struct io_statx
*ctx
= &req
->statx
;
4150 if (issue_flags
& IO_URING_F_NONBLOCK
)
4153 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4157 req_set_fail_links(req
);
4158 io_req_complete(req
, ret
);
4162 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4164 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4166 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4167 sqe
->rw_flags
|| sqe
->buf_index
)
4169 if (req
->flags
& REQ_F_FIXED_FILE
)
4172 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4176 static int io_close(struct io_kiocb
*req
, unsigned int issue_flags
)
4178 struct files_struct
*files
= current
->files
;
4179 struct io_close
*close
= &req
->close
;
4180 struct fdtable
*fdt
;
4181 struct file
*file
= NULL
;
4184 spin_lock(&files
->file_lock
);
4185 fdt
= files_fdtable(files
);
4186 if (close
->fd
>= fdt
->max_fds
) {
4187 spin_unlock(&files
->file_lock
);
4190 file
= fdt
->fd
[close
->fd
];
4191 if (!file
|| file
->f_op
== &io_uring_fops
) {
4192 spin_unlock(&files
->file_lock
);
4197 /* if the file has a flush method, be safe and punt to async */
4198 if (file
->f_op
->flush
&& (issue_flags
& IO_URING_F_NONBLOCK
)) {
4199 spin_unlock(&files
->file_lock
);
4203 ret
= __close_fd_get_file(close
->fd
, &file
);
4204 spin_unlock(&files
->file_lock
);
4211 /* No ->flush() or already async, safely close from here */
4212 ret
= filp_close(file
, current
->files
);
4215 req_set_fail_links(req
);
4218 __io_req_complete(req
, issue_flags
, ret
, 0);
4222 static int io_sfr_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4224 struct io_ring_ctx
*ctx
= req
->ctx
;
4226 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4228 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4231 req
->sync
.off
= READ_ONCE(sqe
->off
);
4232 req
->sync
.len
= READ_ONCE(sqe
->len
);
4233 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4237 static int io_sync_file_range(struct io_kiocb
*req
, unsigned int issue_flags
)
4241 /* sync_file_range always requires a blocking context */
4242 if (issue_flags
& IO_URING_F_NONBLOCK
)
4245 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4248 req_set_fail_links(req
);
4249 io_req_complete(req
, ret
);
4253 #if defined(CONFIG_NET)
4254 static int io_setup_async_msg(struct io_kiocb
*req
,
4255 struct io_async_msghdr
*kmsg
)
4257 struct io_async_msghdr
*async_msg
= req
->async_data
;
4261 if (io_alloc_async_data(req
)) {
4262 kfree(kmsg
->free_iov
);
4265 async_msg
= req
->async_data
;
4266 req
->flags
|= REQ_F_NEED_CLEANUP
;
4267 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4268 async_msg
->msg
.msg_name
= &async_msg
->addr
;
4269 /* if were using fast_iov, set it to the new one */
4270 if (!async_msg
->free_iov
)
4271 async_msg
->msg
.msg_iter
.iov
= async_msg
->fast_iov
;
4276 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4277 struct io_async_msghdr
*iomsg
)
4279 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4280 iomsg
->free_iov
= iomsg
->fast_iov
;
4281 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4282 req
->sr_msg
.msg_flags
, &iomsg
->free_iov
);
4285 static int io_sendmsg_prep_async(struct io_kiocb
*req
)
4289 ret
= io_sendmsg_copy_hdr(req
, req
->async_data
);
4291 req
->flags
|= REQ_F_NEED_CLEANUP
;
4295 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4297 struct io_sr_msg
*sr
= &req
->sr_msg
;
4299 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4302 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4303 sr
->len
= READ_ONCE(sqe
->len
);
4304 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
) | MSG_NOSIGNAL
;
4305 if (sr
->msg_flags
& MSG_DONTWAIT
)
4306 req
->flags
|= REQ_F_NOWAIT
;
4308 #ifdef CONFIG_COMPAT
4309 if (req
->ctx
->compat
)
4310 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4315 static int io_sendmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4317 struct io_async_msghdr iomsg
, *kmsg
;
4318 struct socket
*sock
;
4323 sock
= sock_from_file(req
->file
);
4324 if (unlikely(!sock
))
4327 kmsg
= req
->async_data
;
4329 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4335 flags
= req
->sr_msg
.msg_flags
;
4336 if (issue_flags
& IO_URING_F_NONBLOCK
)
4337 flags
|= MSG_DONTWAIT
;
4338 if (flags
& MSG_WAITALL
)
4339 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
4341 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4342 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4343 return io_setup_async_msg(req
, kmsg
);
4344 if (ret
== -ERESTARTSYS
)
4347 /* fast path, check for non-NULL to avoid function call */
4349 kfree(kmsg
->free_iov
);
4350 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4352 req_set_fail_links(req
);
4353 __io_req_complete(req
, issue_flags
, ret
, 0);
4357 static int io_send(struct io_kiocb
*req
, unsigned int issue_flags
)
4359 struct io_sr_msg
*sr
= &req
->sr_msg
;
4362 struct socket
*sock
;
4367 sock
= sock_from_file(req
->file
);
4368 if (unlikely(!sock
))
4371 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4375 msg
.msg_name
= NULL
;
4376 msg
.msg_control
= NULL
;
4377 msg
.msg_controllen
= 0;
4378 msg
.msg_namelen
= 0;
4380 flags
= req
->sr_msg
.msg_flags
;
4381 if (issue_flags
& IO_URING_F_NONBLOCK
)
4382 flags
|= MSG_DONTWAIT
;
4383 if (flags
& MSG_WAITALL
)
4384 min_ret
= iov_iter_count(&msg
.msg_iter
);
4386 msg
.msg_flags
= flags
;
4387 ret
= sock_sendmsg(sock
, &msg
);
4388 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4390 if (ret
== -ERESTARTSYS
)
4394 req_set_fail_links(req
);
4395 __io_req_complete(req
, issue_flags
, ret
, 0);
4399 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4400 struct io_async_msghdr
*iomsg
)
4402 struct io_sr_msg
*sr
= &req
->sr_msg
;
4403 struct iovec __user
*uiov
;
4407 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4408 &iomsg
->uaddr
, &uiov
, &iov_len
);
4412 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4415 if (copy_from_user(iomsg
->fast_iov
, uiov
, sizeof(*uiov
)))
4417 sr
->len
= iomsg
->fast_iov
[0].iov_len
;
4418 iomsg
->free_iov
= NULL
;
4420 iomsg
->free_iov
= iomsg
->fast_iov
;
4421 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4422 &iomsg
->free_iov
, &iomsg
->msg
.msg_iter
,
4431 #ifdef CONFIG_COMPAT
4432 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4433 struct io_async_msghdr
*iomsg
)
4435 struct io_sr_msg
*sr
= &req
->sr_msg
;
4436 struct compat_iovec __user
*uiov
;
4441 ret
= __get_compat_msghdr(&iomsg
->msg
, sr
->umsg_compat
, &iomsg
->uaddr
,
4446 uiov
= compat_ptr(ptr
);
4447 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4448 compat_ssize_t clen
;
4452 if (!access_ok(uiov
, sizeof(*uiov
)))
4454 if (__get_user(clen
, &uiov
->iov_len
))
4459 iomsg
->free_iov
= NULL
;
4461 iomsg
->free_iov
= iomsg
->fast_iov
;
4462 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4463 UIO_FASTIOV
, &iomsg
->free_iov
,
4464 &iomsg
->msg
.msg_iter
, true);
4473 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4474 struct io_async_msghdr
*iomsg
)
4476 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4478 #ifdef CONFIG_COMPAT
4479 if (req
->ctx
->compat
)
4480 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4483 return __io_recvmsg_copy_hdr(req
, iomsg
);
4486 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4489 struct io_sr_msg
*sr
= &req
->sr_msg
;
4490 struct io_buffer
*kbuf
;
4492 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4497 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4501 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4503 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4506 static int io_recvmsg_prep_async(struct io_kiocb
*req
)
4510 ret
= io_recvmsg_copy_hdr(req
, req
->async_data
);
4512 req
->flags
|= REQ_F_NEED_CLEANUP
;
4516 static int io_recvmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4518 struct io_sr_msg
*sr
= &req
->sr_msg
;
4520 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4523 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4524 sr
->len
= READ_ONCE(sqe
->len
);
4525 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4526 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
) | MSG_NOSIGNAL
;
4527 if (sr
->msg_flags
& MSG_DONTWAIT
)
4528 req
->flags
|= REQ_F_NOWAIT
;
4530 #ifdef CONFIG_COMPAT
4531 if (req
->ctx
->compat
)
4532 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4537 static int io_recvmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4539 struct io_async_msghdr iomsg
, *kmsg
;
4540 struct socket
*sock
;
4541 struct io_buffer
*kbuf
;
4544 int ret
, cflags
= 0;
4545 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4547 sock
= sock_from_file(req
->file
);
4548 if (unlikely(!sock
))
4551 kmsg
= req
->async_data
;
4553 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4559 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4560 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4562 return PTR_ERR(kbuf
);
4563 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4564 kmsg
->fast_iov
[0].iov_len
= req
->sr_msg
.len
;
4565 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->fast_iov
,
4566 1, req
->sr_msg
.len
);
4569 flags
= req
->sr_msg
.msg_flags
;
4571 flags
|= MSG_DONTWAIT
;
4572 if (flags
& MSG_WAITALL
)
4573 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
4575 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4576 kmsg
->uaddr
, flags
);
4577 if (force_nonblock
&& ret
== -EAGAIN
)
4578 return io_setup_async_msg(req
, kmsg
);
4579 if (ret
== -ERESTARTSYS
)
4582 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4583 cflags
= io_put_recv_kbuf(req
);
4584 /* fast path, check for non-NULL to avoid function call */
4586 kfree(kmsg
->free_iov
);
4587 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4588 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (kmsg
->msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
4589 req_set_fail_links(req
);
4590 __io_req_complete(req
, issue_flags
, ret
, cflags
);
4594 static int io_recv(struct io_kiocb
*req
, unsigned int issue_flags
)
4596 struct io_buffer
*kbuf
;
4597 struct io_sr_msg
*sr
= &req
->sr_msg
;
4599 void __user
*buf
= sr
->buf
;
4600 struct socket
*sock
;
4604 int ret
, cflags
= 0;
4605 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4607 sock
= sock_from_file(req
->file
);
4608 if (unlikely(!sock
))
4611 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4612 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4614 return PTR_ERR(kbuf
);
4615 buf
= u64_to_user_ptr(kbuf
->addr
);
4618 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4622 msg
.msg_name
= NULL
;
4623 msg
.msg_control
= NULL
;
4624 msg
.msg_controllen
= 0;
4625 msg
.msg_namelen
= 0;
4626 msg
.msg_iocb
= NULL
;
4629 flags
= req
->sr_msg
.msg_flags
;
4631 flags
|= MSG_DONTWAIT
;
4632 if (flags
& MSG_WAITALL
)
4633 min_ret
= iov_iter_count(&msg
.msg_iter
);
4635 ret
= sock_recvmsg(sock
, &msg
, flags
);
4636 if (force_nonblock
&& ret
== -EAGAIN
)
4638 if (ret
== -ERESTARTSYS
)
4641 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4642 cflags
= io_put_recv_kbuf(req
);
4643 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
4644 req_set_fail_links(req
);
4645 __io_req_complete(req
, issue_flags
, ret
, cflags
);
4649 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4651 struct io_accept
*accept
= &req
->accept
;
4653 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4655 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4658 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4659 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4660 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4661 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4665 static int io_accept(struct io_kiocb
*req
, unsigned int issue_flags
)
4667 struct io_accept
*accept
= &req
->accept
;
4668 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4669 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4672 if (req
->file
->f_flags
& O_NONBLOCK
)
4673 req
->flags
|= REQ_F_NOWAIT
;
4675 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4676 accept
->addr_len
, accept
->flags
,
4678 if (ret
== -EAGAIN
&& force_nonblock
)
4681 if (ret
== -ERESTARTSYS
)
4683 req_set_fail_links(req
);
4685 __io_req_complete(req
, issue_flags
, ret
, 0);
4689 static int io_connect_prep_async(struct io_kiocb
*req
)
4691 struct io_async_connect
*io
= req
->async_data
;
4692 struct io_connect
*conn
= &req
->connect
;
4694 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
, &io
->address
);
4697 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4699 struct io_connect
*conn
= &req
->connect
;
4701 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4703 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4706 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4707 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4711 static int io_connect(struct io_kiocb
*req
, unsigned int issue_flags
)
4713 struct io_async_connect __io
, *io
;
4714 unsigned file_flags
;
4716 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4718 if (req
->async_data
) {
4719 io
= req
->async_data
;
4721 ret
= move_addr_to_kernel(req
->connect
.addr
,
4722 req
->connect
.addr_len
,
4729 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4731 ret
= __sys_connect_file(req
->file
, &io
->address
,
4732 req
->connect
.addr_len
, file_flags
);
4733 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4734 if (req
->async_data
)
4736 if (io_alloc_async_data(req
)) {
4740 memcpy(req
->async_data
, &__io
, sizeof(__io
));
4743 if (ret
== -ERESTARTSYS
)
4747 req_set_fail_links(req
);
4748 __io_req_complete(req
, issue_flags
, ret
, 0);
4751 #else /* !CONFIG_NET */
4752 #define IO_NETOP_FN(op) \
4753 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
4755 return -EOPNOTSUPP; \
4758 #define IO_NETOP_PREP(op) \
4760 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
4762 return -EOPNOTSUPP; \
4765 #define IO_NETOP_PREP_ASYNC(op) \
4767 static int io_##op##_prep_async(struct io_kiocb *req) \
4769 return -EOPNOTSUPP; \
4772 IO_NETOP_PREP_ASYNC(sendmsg
);
4773 IO_NETOP_PREP_ASYNC(recvmsg
);
4774 IO_NETOP_PREP_ASYNC(connect
);
4775 IO_NETOP_PREP(accept
);
4778 #endif /* CONFIG_NET */
4780 struct io_poll_table
{
4781 struct poll_table_struct pt
;
4782 struct io_kiocb
*req
;
4786 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4787 __poll_t mask
, task_work_func_t func
)
4791 /* for instances that support it check for an event match first: */
4792 if (mask
&& !(mask
& poll
->events
))
4795 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4797 list_del_init(&poll
->wait
.entry
);
4800 req
->task_work
.func
= func
;
4803 * If this fails, then the task is exiting. When a task exits, the
4804 * work gets canceled, so just cancel this request as well instead
4805 * of executing it. We can't safely execute it anyway, as we may not
4806 * have the needed state needed for it anyway.
4808 ret
= io_req_task_work_add(req
);
4809 if (unlikely(ret
)) {
4810 WRITE_ONCE(poll
->canceled
, true);
4811 io_req_task_work_add_fallback(req
, func
);
4816 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4817 __acquires(&req
->ctx
->completion_lock
)
4819 struct io_ring_ctx
*ctx
= req
->ctx
;
4821 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4822 struct poll_table_struct pt
= { ._key
= poll
->events
};
4824 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4827 spin_lock_irq(&ctx
->completion_lock
);
4828 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4829 add_wait_queue(poll
->head
, &poll
->wait
);
4836 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
4838 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
4839 if (req
->opcode
== IORING_OP_POLL_ADD
)
4840 return req
->async_data
;
4841 return req
->apoll
->double_poll
;
4844 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
4846 if (req
->opcode
== IORING_OP_POLL_ADD
)
4848 return &req
->apoll
->poll
;
4851 static void io_poll_remove_double(struct io_kiocb
*req
)
4852 __must_hold(&req
->ctx
->completion_lock
)
4854 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
4856 lockdep_assert_held(&req
->ctx
->completion_lock
);
4858 if (poll
&& poll
->head
) {
4859 struct wait_queue_head
*head
= poll
->head
;
4861 spin_lock(&head
->lock
);
4862 list_del_init(&poll
->wait
.entry
);
4863 if (poll
->wait
.private)
4866 spin_unlock(&head
->lock
);
4870 static bool io_poll_complete(struct io_kiocb
*req
, __poll_t mask
)
4871 __must_hold(&req
->ctx
->completion_lock
)
4873 struct io_ring_ctx
*ctx
= req
->ctx
;
4874 unsigned flags
= IORING_CQE_F_MORE
;
4877 if (READ_ONCE(req
->poll
.canceled
)) {
4879 req
->poll
.events
|= EPOLLONESHOT
;
4881 error
= mangle_poll(mask
);
4883 if (req
->poll
.events
& EPOLLONESHOT
)
4885 if (!io_cqring_fill_event(req
, error
, flags
)) {
4886 io_poll_remove_waitqs(req
);
4887 req
->poll
.done
= true;
4890 io_commit_cqring(ctx
);
4891 return !(flags
& IORING_CQE_F_MORE
);
4894 static void io_poll_task_func(struct callback_head
*cb
)
4896 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4897 struct io_ring_ctx
*ctx
= req
->ctx
;
4898 struct io_kiocb
*nxt
;
4900 if (io_poll_rewait(req
, &req
->poll
)) {
4901 spin_unlock_irq(&ctx
->completion_lock
);
4905 done
= io_poll_complete(req
, req
->result
);
4907 hash_del(&req
->hash_node
);
4910 add_wait_queue(req
->poll
.head
, &req
->poll
.wait
);
4912 spin_unlock_irq(&ctx
->completion_lock
);
4913 io_cqring_ev_posted(ctx
);
4916 nxt
= io_put_req_find_next(req
);
4918 __io_req_task_submit(nxt
);
4923 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4924 int sync
, void *key
)
4926 struct io_kiocb
*req
= wait
->private;
4927 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
4928 __poll_t mask
= key_to_poll(key
);
4930 /* for instances that support it check for an event match first: */
4931 if (mask
&& !(mask
& poll
->events
))
4933 if (!(poll
->events
& EPOLLONESHOT
))
4934 return poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
4936 list_del_init(&wait
->entry
);
4938 if (poll
&& poll
->head
) {
4941 spin_lock(&poll
->head
->lock
);
4942 done
= list_empty(&poll
->wait
.entry
);
4944 list_del_init(&poll
->wait
.entry
);
4945 /* make sure double remove sees this as being gone */
4946 wait
->private = NULL
;
4947 spin_unlock(&poll
->head
->lock
);
4949 /* use wait func handler, so it matches the rq type */
4950 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
4957 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
4958 wait_queue_func_t wake_func
)
4962 poll
->canceled
= false;
4963 #define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
4964 /* mask in events that we always want/need */
4965 poll
->events
= events
| IO_POLL_UNMASK
;
4966 INIT_LIST_HEAD(&poll
->wait
.entry
);
4967 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
4970 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
4971 struct wait_queue_head
*head
,
4972 struct io_poll_iocb
**poll_ptr
)
4974 struct io_kiocb
*req
= pt
->req
;
4977 * If poll->head is already set, it's because the file being polled
4978 * uses multiple waitqueues for poll handling (eg one for read, one
4979 * for write). Setup a separate io_poll_iocb if this happens.
4981 if (unlikely(poll
->head
)) {
4982 struct io_poll_iocb
*poll_one
= poll
;
4984 /* already have a 2nd entry, fail a third attempt */
4986 pt
->error
= -EINVAL
;
4990 * Can't handle multishot for double wait for now, turn it
4991 * into one-shot mode.
4993 if (!(req
->poll
.events
& EPOLLONESHOT
))
4994 req
->poll
.events
|= EPOLLONESHOT
;
4995 /* double add on the same waitqueue head, ignore */
4996 if (poll
->head
== head
)
4998 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5000 pt
->error
= -ENOMEM
;
5003 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5005 poll
->wait
.private = req
;
5012 if (poll
->events
& EPOLLEXCLUSIVE
)
5013 add_wait_queue_exclusive(head
, &poll
->wait
);
5015 add_wait_queue(head
, &poll
->wait
);
5018 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5019 struct poll_table_struct
*p
)
5021 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5022 struct async_poll
*apoll
= pt
->req
->apoll
;
5024 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5027 static void io_async_task_func(struct callback_head
*cb
)
5029 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5030 struct async_poll
*apoll
= req
->apoll
;
5031 struct io_ring_ctx
*ctx
= req
->ctx
;
5033 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5035 if (io_poll_rewait(req
, &apoll
->poll
)) {
5036 spin_unlock_irq(&ctx
->completion_lock
);
5040 hash_del(&req
->hash_node
);
5041 io_poll_remove_double(req
);
5042 spin_unlock_irq(&ctx
->completion_lock
);
5044 if (!READ_ONCE(apoll
->poll
.canceled
))
5045 __io_req_task_submit(req
);
5047 io_req_complete_failed(req
, -ECANCELED
);
5050 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5053 struct io_kiocb
*req
= wait
->private;
5054 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5056 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5059 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5062 static void io_poll_req_insert(struct io_kiocb
*req
)
5064 struct io_ring_ctx
*ctx
= req
->ctx
;
5065 struct hlist_head
*list
;
5067 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5068 hlist_add_head(&req
->hash_node
, list
);
5071 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5072 struct io_poll_iocb
*poll
,
5073 struct io_poll_table
*ipt
, __poll_t mask
,
5074 wait_queue_func_t wake_func
)
5075 __acquires(&ctx
->completion_lock
)
5077 struct io_ring_ctx
*ctx
= req
->ctx
;
5078 bool cancel
= false;
5080 INIT_HLIST_NODE(&req
->hash_node
);
5081 io_init_poll_iocb(poll
, mask
, wake_func
);
5082 poll
->file
= req
->file
;
5083 poll
->wait
.private = req
;
5085 ipt
->pt
._key
= mask
;
5087 ipt
->error
= -EINVAL
;
5089 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5091 spin_lock_irq(&ctx
->completion_lock
);
5092 if (likely(poll
->head
)) {
5093 spin_lock(&poll
->head
->lock
);
5094 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5100 if ((mask
&& (poll
->events
& EPOLLONESHOT
)) || ipt
->error
)
5101 list_del_init(&poll
->wait
.entry
);
5103 WRITE_ONCE(poll
->canceled
, true);
5104 else if (!poll
->done
) /* actually waiting for an event */
5105 io_poll_req_insert(req
);
5106 spin_unlock(&poll
->head
->lock
);
5112 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5114 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5115 struct io_ring_ctx
*ctx
= req
->ctx
;
5116 struct async_poll
*apoll
;
5117 struct io_poll_table ipt
;
5121 if (!req
->file
|| !file_can_poll(req
->file
))
5123 if (req
->flags
& REQ_F_POLLED
)
5127 else if (def
->pollout
)
5131 /* if we can't nonblock try, then no point in arming a poll handler */
5132 if (!io_file_supports_async(req
, rw
))
5135 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5136 if (unlikely(!apoll
))
5138 apoll
->double_poll
= NULL
;
5140 req
->flags
|= REQ_F_POLLED
;
5143 mask
= EPOLLONESHOT
;
5145 mask
|= POLLIN
| POLLRDNORM
;
5147 mask
|= POLLOUT
| POLLWRNORM
;
5149 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5150 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5151 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5154 mask
|= POLLERR
| POLLPRI
;
5156 ipt
.pt
._qproc
= io_async_queue_proc
;
5158 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5160 if (ret
|| ipt
.error
) {
5161 io_poll_remove_double(req
);
5162 spin_unlock_irq(&ctx
->completion_lock
);
5165 spin_unlock_irq(&ctx
->completion_lock
);
5166 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5167 apoll
->poll
.events
);
5171 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5172 struct io_poll_iocb
*poll
, bool do_cancel
)
5173 __must_hold(&req
->ctx
->completion_lock
)
5175 bool do_complete
= false;
5179 spin_lock(&poll
->head
->lock
);
5181 WRITE_ONCE(poll
->canceled
, true);
5182 if (!list_empty(&poll
->wait
.entry
)) {
5183 list_del_init(&poll
->wait
.entry
);
5186 spin_unlock(&poll
->head
->lock
);
5187 hash_del(&req
->hash_node
);
5191 static bool io_poll_remove_waitqs(struct io_kiocb
*req
)
5192 __must_hold(&req
->ctx
->completion_lock
)
5196 io_poll_remove_double(req
);
5197 do_complete
= __io_poll_remove_one(req
, io_poll_get_single(req
), true);
5199 if (req
->opcode
!= IORING_OP_POLL_ADD
&& do_complete
) {
5200 /* non-poll requests have submit ref still */
5206 static bool io_poll_remove_one(struct io_kiocb
*req
)
5207 __must_hold(&req
->ctx
->completion_lock
)
5211 do_complete
= io_poll_remove_waitqs(req
);
5213 io_cqring_fill_event(req
, -ECANCELED
, 0);
5214 io_commit_cqring(req
->ctx
);
5215 req_set_fail_links(req
);
5216 io_put_req_deferred(req
, 1);
5223 * Returns true if we found and killed one or more poll requests
5225 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5226 struct files_struct
*files
)
5228 struct hlist_node
*tmp
;
5229 struct io_kiocb
*req
;
5232 spin_lock_irq(&ctx
->completion_lock
);
5233 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5234 struct hlist_head
*list
;
5236 list
= &ctx
->cancel_hash
[i
];
5237 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5238 if (io_match_task(req
, tsk
, files
))
5239 posted
+= io_poll_remove_one(req
);
5242 spin_unlock_irq(&ctx
->completion_lock
);
5245 io_cqring_ev_posted(ctx
);
5250 static struct io_kiocb
*io_poll_find(struct io_ring_ctx
*ctx
, __u64 sqe_addr
,
5252 __must_hold(&ctx
->completion_lock
)
5254 struct hlist_head
*list
;
5255 struct io_kiocb
*req
;
5257 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5258 hlist_for_each_entry(req
, list
, hash_node
) {
5259 if (sqe_addr
!= req
->user_data
)
5261 if (poll_only
&& req
->opcode
!= IORING_OP_POLL_ADD
)
5268 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
,
5270 __must_hold(&ctx
->completion_lock
)
5272 struct io_kiocb
*req
;
5274 req
= io_poll_find(ctx
, sqe_addr
, poll_only
);
5277 if (io_poll_remove_one(req
))
5283 static __poll_t
io_poll_parse_events(const struct io_uring_sqe
*sqe
,
5288 events
= READ_ONCE(sqe
->poll32_events
);
5290 events
= swahw32(events
);
5292 if (!(flags
& IORING_POLL_ADD_MULTI
))
5293 events
|= EPOLLONESHOT
;
5294 return demangle_poll(events
) | (events
& (EPOLLEXCLUSIVE
|EPOLLONESHOT
));
5297 static int io_poll_update_prep(struct io_kiocb
*req
,
5298 const struct io_uring_sqe
*sqe
)
5300 struct io_poll_update
*upd
= &req
->poll_update
;
5303 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5305 if (sqe
->ioprio
|| sqe
->buf_index
)
5307 flags
= READ_ONCE(sqe
->len
);
5308 if (flags
& ~(IORING_POLL_UPDATE_EVENTS
| IORING_POLL_UPDATE_USER_DATA
|
5309 IORING_POLL_ADD_MULTI
))
5311 /* meaningless without update */
5312 if (flags
== IORING_POLL_ADD_MULTI
)
5315 upd
->old_user_data
= READ_ONCE(sqe
->addr
);
5316 upd
->update_events
= flags
& IORING_POLL_UPDATE_EVENTS
;
5317 upd
->update_user_data
= flags
& IORING_POLL_UPDATE_USER_DATA
;
5319 upd
->new_user_data
= READ_ONCE(sqe
->off
);
5320 if (!upd
->update_user_data
&& upd
->new_user_data
)
5322 if (upd
->update_events
)
5323 upd
->events
= io_poll_parse_events(sqe
, flags
);
5324 else if (sqe
->poll32_events
)
5330 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5333 struct io_kiocb
*req
= wait
->private;
5334 struct io_poll_iocb
*poll
= &req
->poll
;
5336 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5339 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5340 struct poll_table_struct
*p
)
5342 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5344 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5347 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5349 struct io_poll_iocb
*poll
= &req
->poll
;
5352 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5354 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
|| sqe
->addr
)
5356 flags
= READ_ONCE(sqe
->len
);
5357 if (flags
& ~IORING_POLL_ADD_MULTI
)
5360 poll
->events
= io_poll_parse_events(sqe
, flags
);
5364 static int io_poll_add(struct io_kiocb
*req
, unsigned int issue_flags
)
5366 struct io_poll_iocb
*poll
= &req
->poll
;
5367 struct io_ring_ctx
*ctx
= req
->ctx
;
5368 struct io_poll_table ipt
;
5371 ipt
.pt
._qproc
= io_poll_queue_proc
;
5373 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5376 if (mask
) { /* no async, we'd stolen it */
5378 io_poll_complete(req
, mask
);
5380 spin_unlock_irq(&ctx
->completion_lock
);
5383 io_cqring_ev_posted(ctx
);
5384 if (poll
->events
& EPOLLONESHOT
)
5390 static int io_poll_update(struct io_kiocb
*req
, unsigned int issue_flags
)
5392 struct io_ring_ctx
*ctx
= req
->ctx
;
5393 struct io_kiocb
*preq
;
5397 spin_lock_irq(&ctx
->completion_lock
);
5398 preq
= io_poll_find(ctx
, req
->poll_update
.old_user_data
, true);
5404 if (!req
->poll_update
.update_events
&& !req
->poll_update
.update_user_data
) {
5406 ret
= io_poll_remove_one(preq
) ? 0 : -EALREADY
;
5411 * Don't allow racy completion with singleshot, as we cannot safely
5412 * update those. For multishot, if we're racing with completion, just
5413 * let completion re-add it.
5415 completing
= !__io_poll_remove_one(preq
, &preq
->poll
, false);
5416 if (completing
&& (preq
->poll
.events
& EPOLLONESHOT
)) {
5420 /* we now have a detached poll request. reissue. */
5424 spin_unlock_irq(&ctx
->completion_lock
);
5425 req_set_fail_links(req
);
5426 io_req_complete(req
, ret
);
5429 /* only mask one event flags, keep behavior flags */
5430 if (req
->poll_update
.update_events
) {
5431 preq
->poll
.events
&= ~0xffff;
5432 preq
->poll
.events
|= req
->poll_update
.events
& 0xffff;
5433 preq
->poll
.events
|= IO_POLL_UNMASK
;
5435 if (req
->poll_update
.update_user_data
)
5436 preq
->user_data
= req
->poll_update
.new_user_data
;
5437 spin_unlock_irq(&ctx
->completion_lock
);
5439 /* complete update request, we're done with it */
5440 io_req_complete(req
, ret
);
5443 ret
= io_poll_add(preq
, issue_flags
);
5445 req_set_fail_links(preq
);
5446 io_req_complete(preq
, ret
);
5452 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5454 struct io_timeout_data
*data
= container_of(timer
,
5455 struct io_timeout_data
, timer
);
5456 struct io_kiocb
*req
= data
->req
;
5457 struct io_ring_ctx
*ctx
= req
->ctx
;
5458 unsigned long flags
;
5460 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5461 list_del_init(&req
->timeout
.list
);
5462 atomic_set(&req
->ctx
->cq_timeouts
,
5463 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5465 io_cqring_fill_event(req
, -ETIME
, 0);
5466 io_commit_cqring(ctx
);
5467 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5469 io_cqring_ev_posted(ctx
);
5470 req_set_fail_links(req
);
5472 return HRTIMER_NORESTART
;
5475 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5477 __must_hold(&ctx
->completion_lock
)
5479 struct io_timeout_data
*io
;
5480 struct io_kiocb
*req
;
5483 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5484 found
= user_data
== req
->user_data
;
5489 return ERR_PTR(-ENOENT
);
5491 io
= req
->async_data
;
5492 if (hrtimer_try_to_cancel(&io
->timer
) == -1)
5493 return ERR_PTR(-EALREADY
);
5494 list_del_init(&req
->timeout
.list
);
5498 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5499 __must_hold(&ctx
->completion_lock
)
5501 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5504 return PTR_ERR(req
);
5506 req_set_fail_links(req
);
5507 io_cqring_fill_event(req
, -ECANCELED
, 0);
5508 io_put_req_deferred(req
, 1);
5512 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
5513 struct timespec64
*ts
, enum hrtimer_mode mode
)
5514 __must_hold(&ctx
->completion_lock
)
5516 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5517 struct io_timeout_data
*data
;
5520 return PTR_ERR(req
);
5522 req
->timeout
.off
= 0; /* noseq */
5523 data
= req
->async_data
;
5524 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
5525 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, mode
);
5526 data
->timer
.function
= io_timeout_fn
;
5527 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
5531 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5532 const struct io_uring_sqe
*sqe
)
5534 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5536 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5538 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5540 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5543 tr
->addr
= READ_ONCE(sqe
->addr
);
5544 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
5545 if (tr
->flags
& IORING_TIMEOUT_UPDATE
) {
5546 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE
|IORING_TIMEOUT_ABS
))
5548 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
5550 } else if (tr
->flags
) {
5551 /* timeout removal doesn't support flags */
5558 static inline enum hrtimer_mode
io_translate_timeout_mode(unsigned int flags
)
5560 return (flags
& IORING_TIMEOUT_ABS
) ? HRTIMER_MODE_ABS
5565 * Remove or update an existing timeout command
5567 static int io_timeout_remove(struct io_kiocb
*req
, unsigned int issue_flags
)
5569 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5570 struct io_ring_ctx
*ctx
= req
->ctx
;
5573 spin_lock_irq(&ctx
->completion_lock
);
5574 if (!(req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
))
5575 ret
= io_timeout_cancel(ctx
, tr
->addr
);
5577 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
,
5578 io_translate_timeout_mode(tr
->flags
));
5580 io_cqring_fill_event(req
, ret
, 0);
5581 io_commit_cqring(ctx
);
5582 spin_unlock_irq(&ctx
->completion_lock
);
5583 io_cqring_ev_posted(ctx
);
5585 req_set_fail_links(req
);
5590 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5591 bool is_timeout_link
)
5593 struct io_timeout_data
*data
;
5595 u32 off
= READ_ONCE(sqe
->off
);
5597 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5599 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5601 if (off
&& is_timeout_link
)
5603 flags
= READ_ONCE(sqe
->timeout_flags
);
5604 if (flags
& ~IORING_TIMEOUT_ABS
)
5607 req
->timeout
.off
= off
;
5609 if (!req
->async_data
&& io_alloc_async_data(req
))
5612 data
= req
->async_data
;
5615 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5618 data
->mode
= io_translate_timeout_mode(flags
);
5619 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5620 if (is_timeout_link
)
5621 io_req_track_inflight(req
);
5625 static int io_timeout(struct io_kiocb
*req
, unsigned int issue_flags
)
5627 struct io_ring_ctx
*ctx
= req
->ctx
;
5628 struct io_timeout_data
*data
= req
->async_data
;
5629 struct list_head
*entry
;
5630 u32 tail
, off
= req
->timeout
.off
;
5632 spin_lock_irq(&ctx
->completion_lock
);
5635 * sqe->off holds how many events that need to occur for this
5636 * timeout event to be satisfied. If it isn't set, then this is
5637 * a pure timeout request, sequence isn't used.
5639 if (io_is_timeout_noseq(req
)) {
5640 entry
= ctx
->timeout_list
.prev
;
5644 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5645 req
->timeout
.target_seq
= tail
+ off
;
5647 /* Update the last seq here in case io_flush_timeouts() hasn't.
5648 * This is safe because ->completion_lock is held, and submissions
5649 * and completions are never mixed in the same ->completion_lock section.
5651 ctx
->cq_last_tm_flush
= tail
;
5654 * Insertion sort, ensuring the first entry in the list is always
5655 * the one we need first.
5657 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5658 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5661 if (io_is_timeout_noseq(nxt
))
5663 /* nxt.seq is behind @tail, otherwise would've been completed */
5664 if (off
>= nxt
->timeout
.target_seq
- tail
)
5668 list_add(&req
->timeout
.list
, entry
);
5669 data
->timer
.function
= io_timeout_fn
;
5670 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5671 spin_unlock_irq(&ctx
->completion_lock
);
5675 struct io_cancel_data
{
5676 struct io_ring_ctx
*ctx
;
5680 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5682 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5683 struct io_cancel_data
*cd
= data
;
5685 return req
->ctx
== cd
->ctx
&& req
->user_data
== cd
->user_data
;
5688 static int io_async_cancel_one(struct io_uring_task
*tctx
, u64 user_data
,
5689 struct io_ring_ctx
*ctx
)
5691 struct io_cancel_data data
= { .ctx
= ctx
, .user_data
= user_data
, };
5692 enum io_wq_cancel cancel_ret
;
5695 if (!tctx
|| !tctx
->io_wq
)
5698 cancel_ret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_cb
, &data
, false);
5699 switch (cancel_ret
) {
5700 case IO_WQ_CANCEL_OK
:
5703 case IO_WQ_CANCEL_RUNNING
:
5706 case IO_WQ_CANCEL_NOTFOUND
:
5714 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5715 struct io_kiocb
*req
, __u64 sqe_addr
,
5718 unsigned long flags
;
5721 ret
= io_async_cancel_one(req
->task
->io_uring
, sqe_addr
, ctx
);
5722 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5725 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5728 ret
= io_poll_cancel(ctx
, sqe_addr
, false);
5732 io_cqring_fill_event(req
, ret
, 0);
5733 io_commit_cqring(ctx
);
5734 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5735 io_cqring_ev_posted(ctx
);
5738 req_set_fail_links(req
);
5741 static int io_async_cancel_prep(struct io_kiocb
*req
,
5742 const struct io_uring_sqe
*sqe
)
5744 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5746 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5748 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5751 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5755 static int io_async_cancel(struct io_kiocb
*req
, unsigned int issue_flags
)
5757 struct io_ring_ctx
*ctx
= req
->ctx
;
5758 u64 sqe_addr
= req
->cancel
.addr
;
5759 struct io_tctx_node
*node
;
5762 /* tasks should wait for their io-wq threads, so safe w/o sync */
5763 ret
= io_async_cancel_one(req
->task
->io_uring
, sqe_addr
, ctx
);
5764 spin_lock_irq(&ctx
->completion_lock
);
5767 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5770 ret
= io_poll_cancel(ctx
, sqe_addr
, false);
5773 spin_unlock_irq(&ctx
->completion_lock
);
5775 /* slow path, try all io-wq's */
5776 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
5778 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
5779 struct io_uring_task
*tctx
= node
->task
->io_uring
;
5781 ret
= io_async_cancel_one(tctx
, req
->cancel
.addr
, ctx
);
5785 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
5787 spin_lock_irq(&ctx
->completion_lock
);
5789 io_cqring_fill_event(req
, ret
, 0);
5790 io_commit_cqring(ctx
);
5791 spin_unlock_irq(&ctx
->completion_lock
);
5792 io_cqring_ev_posted(ctx
);
5795 req_set_fail_links(req
);
5800 static int io_rsrc_update_prep(struct io_kiocb
*req
,
5801 const struct io_uring_sqe
*sqe
)
5803 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
5805 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5807 if (sqe
->ioprio
|| sqe
->rw_flags
)
5810 req
->rsrc_update
.offset
= READ_ONCE(sqe
->off
);
5811 req
->rsrc_update
.nr_args
= READ_ONCE(sqe
->len
);
5812 if (!req
->rsrc_update
.nr_args
)
5814 req
->rsrc_update
.arg
= READ_ONCE(sqe
->addr
);
5818 static int io_files_update(struct io_kiocb
*req
, unsigned int issue_flags
)
5820 struct io_ring_ctx
*ctx
= req
->ctx
;
5821 struct io_uring_rsrc_update up
;
5824 if (issue_flags
& IO_URING_F_NONBLOCK
)
5827 up
.offset
= req
->rsrc_update
.offset
;
5828 up
.data
= req
->rsrc_update
.arg
;
5830 mutex_lock(&ctx
->uring_lock
);
5831 ret
= __io_sqe_files_update(ctx
, &up
, req
->rsrc_update
.nr_args
);
5832 mutex_unlock(&ctx
->uring_lock
);
5835 req_set_fail_links(req
);
5836 __io_req_complete(req
, issue_flags
, ret
, 0);
5840 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5842 switch (req
->opcode
) {
5845 case IORING_OP_READV
:
5846 case IORING_OP_READ_FIXED
:
5847 case IORING_OP_READ
:
5848 return io_read_prep(req
, sqe
);
5849 case IORING_OP_WRITEV
:
5850 case IORING_OP_WRITE_FIXED
:
5851 case IORING_OP_WRITE
:
5852 return io_write_prep(req
, sqe
);
5853 case IORING_OP_POLL_ADD
:
5854 return io_poll_add_prep(req
, sqe
);
5855 case IORING_OP_POLL_REMOVE
:
5856 return io_poll_update_prep(req
, sqe
);
5857 case IORING_OP_FSYNC
:
5858 return io_fsync_prep(req
, sqe
);
5859 case IORING_OP_SYNC_FILE_RANGE
:
5860 return io_sfr_prep(req
, sqe
);
5861 case IORING_OP_SENDMSG
:
5862 case IORING_OP_SEND
:
5863 return io_sendmsg_prep(req
, sqe
);
5864 case IORING_OP_RECVMSG
:
5865 case IORING_OP_RECV
:
5866 return io_recvmsg_prep(req
, sqe
);
5867 case IORING_OP_CONNECT
:
5868 return io_connect_prep(req
, sqe
);
5869 case IORING_OP_TIMEOUT
:
5870 return io_timeout_prep(req
, sqe
, false);
5871 case IORING_OP_TIMEOUT_REMOVE
:
5872 return io_timeout_remove_prep(req
, sqe
);
5873 case IORING_OP_ASYNC_CANCEL
:
5874 return io_async_cancel_prep(req
, sqe
);
5875 case IORING_OP_LINK_TIMEOUT
:
5876 return io_timeout_prep(req
, sqe
, true);
5877 case IORING_OP_ACCEPT
:
5878 return io_accept_prep(req
, sqe
);
5879 case IORING_OP_FALLOCATE
:
5880 return io_fallocate_prep(req
, sqe
);
5881 case IORING_OP_OPENAT
:
5882 return io_openat_prep(req
, sqe
);
5883 case IORING_OP_CLOSE
:
5884 return io_close_prep(req
, sqe
);
5885 case IORING_OP_FILES_UPDATE
:
5886 return io_rsrc_update_prep(req
, sqe
);
5887 case IORING_OP_STATX
:
5888 return io_statx_prep(req
, sqe
);
5889 case IORING_OP_FADVISE
:
5890 return io_fadvise_prep(req
, sqe
);
5891 case IORING_OP_MADVISE
:
5892 return io_madvise_prep(req
, sqe
);
5893 case IORING_OP_OPENAT2
:
5894 return io_openat2_prep(req
, sqe
);
5895 case IORING_OP_EPOLL_CTL
:
5896 return io_epoll_ctl_prep(req
, sqe
);
5897 case IORING_OP_SPLICE
:
5898 return io_splice_prep(req
, sqe
);
5899 case IORING_OP_PROVIDE_BUFFERS
:
5900 return io_provide_buffers_prep(req
, sqe
);
5901 case IORING_OP_REMOVE_BUFFERS
:
5902 return io_remove_buffers_prep(req
, sqe
);
5904 return io_tee_prep(req
, sqe
);
5905 case IORING_OP_SHUTDOWN
:
5906 return io_shutdown_prep(req
, sqe
);
5907 case IORING_OP_RENAMEAT
:
5908 return io_renameat_prep(req
, sqe
);
5909 case IORING_OP_UNLINKAT
:
5910 return io_unlinkat_prep(req
, sqe
);
5913 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5918 static int io_req_prep_async(struct io_kiocb
*req
)
5920 if (!io_op_defs
[req
->opcode
].needs_async_setup
)
5922 if (WARN_ON_ONCE(req
->async_data
))
5924 if (io_alloc_async_data(req
))
5927 switch (req
->opcode
) {
5928 case IORING_OP_READV
:
5929 return io_rw_prep_async(req
, READ
);
5930 case IORING_OP_WRITEV
:
5931 return io_rw_prep_async(req
, WRITE
);
5932 case IORING_OP_SENDMSG
:
5933 return io_sendmsg_prep_async(req
);
5934 case IORING_OP_RECVMSG
:
5935 return io_recvmsg_prep_async(req
);
5936 case IORING_OP_CONNECT
:
5937 return io_connect_prep_async(req
);
5939 printk_once(KERN_WARNING
"io_uring: prep_async() bad opcode %d\n",
5944 static u32
io_get_sequence(struct io_kiocb
*req
)
5946 struct io_kiocb
*pos
;
5947 struct io_ring_ctx
*ctx
= req
->ctx
;
5948 u32 total_submitted
, nr_reqs
= 0;
5950 io_for_each_link(pos
, req
)
5953 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5954 return total_submitted
- nr_reqs
;
5957 static int io_req_defer(struct io_kiocb
*req
)
5959 struct io_ring_ctx
*ctx
= req
->ctx
;
5960 struct io_defer_entry
*de
;
5964 /* Still need defer if there is pending req in defer list. */
5965 if (likely(list_empty_careful(&ctx
->defer_list
) &&
5966 !(req
->flags
& REQ_F_IO_DRAIN
)))
5969 seq
= io_get_sequence(req
);
5970 /* Still a chance to pass the sequence check */
5971 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
5974 ret
= io_req_prep_async(req
);
5977 io_prep_async_link(req
);
5978 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
5982 spin_lock_irq(&ctx
->completion_lock
);
5983 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
5984 spin_unlock_irq(&ctx
->completion_lock
);
5986 io_queue_async_work(req
);
5987 return -EIOCBQUEUED
;
5990 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5993 list_add_tail(&de
->list
, &ctx
->defer_list
);
5994 spin_unlock_irq(&ctx
->completion_lock
);
5995 return -EIOCBQUEUED
;
5998 static void io_clean_op(struct io_kiocb
*req
)
6000 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6001 switch (req
->opcode
) {
6002 case IORING_OP_READV
:
6003 case IORING_OP_READ_FIXED
:
6004 case IORING_OP_READ
:
6005 kfree((void *)(unsigned long)req
->rw
.addr
);
6007 case IORING_OP_RECVMSG
:
6008 case IORING_OP_RECV
:
6009 kfree(req
->sr_msg
.kbuf
);
6012 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
6015 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6016 switch (req
->opcode
) {
6017 case IORING_OP_READV
:
6018 case IORING_OP_READ_FIXED
:
6019 case IORING_OP_READ
:
6020 case IORING_OP_WRITEV
:
6021 case IORING_OP_WRITE_FIXED
:
6022 case IORING_OP_WRITE
: {
6023 struct io_async_rw
*io
= req
->async_data
;
6025 kfree(io
->free_iovec
);
6028 case IORING_OP_RECVMSG
:
6029 case IORING_OP_SENDMSG
: {
6030 struct io_async_msghdr
*io
= req
->async_data
;
6032 kfree(io
->free_iov
);
6035 case IORING_OP_SPLICE
:
6037 if (!(req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
))
6038 io_put_file(req
->splice
.file_in
);
6040 case IORING_OP_OPENAT
:
6041 case IORING_OP_OPENAT2
:
6042 if (req
->open
.filename
)
6043 putname(req
->open
.filename
);
6045 case IORING_OP_RENAMEAT
:
6046 putname(req
->rename
.oldpath
);
6047 putname(req
->rename
.newpath
);
6049 case IORING_OP_UNLINKAT
:
6050 putname(req
->unlink
.filename
);
6053 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
6055 if ((req
->flags
& REQ_F_POLLED
) && req
->apoll
) {
6056 kfree(req
->apoll
->double_poll
);
6062 static int io_issue_sqe(struct io_kiocb
*req
, unsigned int issue_flags
)
6064 struct io_ring_ctx
*ctx
= req
->ctx
;
6065 const struct cred
*creds
= NULL
;
6068 if (req
->work
.creds
&& req
->work
.creds
!= current_cred())
6069 creds
= override_creds(req
->work
.creds
);
6071 switch (req
->opcode
) {
6073 ret
= io_nop(req
, issue_flags
);
6075 case IORING_OP_READV
:
6076 case IORING_OP_READ_FIXED
:
6077 case IORING_OP_READ
:
6078 ret
= io_read(req
, issue_flags
);
6080 case IORING_OP_WRITEV
:
6081 case IORING_OP_WRITE_FIXED
:
6082 case IORING_OP_WRITE
:
6083 ret
= io_write(req
, issue_flags
);
6085 case IORING_OP_FSYNC
:
6086 ret
= io_fsync(req
, issue_flags
);
6088 case IORING_OP_POLL_ADD
:
6089 ret
= io_poll_add(req
, issue_flags
);
6091 case IORING_OP_POLL_REMOVE
:
6092 ret
= io_poll_update(req
, issue_flags
);
6094 case IORING_OP_SYNC_FILE_RANGE
:
6095 ret
= io_sync_file_range(req
, issue_flags
);
6097 case IORING_OP_SENDMSG
:
6098 ret
= io_sendmsg(req
, issue_flags
);
6100 case IORING_OP_SEND
:
6101 ret
= io_send(req
, issue_flags
);
6103 case IORING_OP_RECVMSG
:
6104 ret
= io_recvmsg(req
, issue_flags
);
6106 case IORING_OP_RECV
:
6107 ret
= io_recv(req
, issue_flags
);
6109 case IORING_OP_TIMEOUT
:
6110 ret
= io_timeout(req
, issue_flags
);
6112 case IORING_OP_TIMEOUT_REMOVE
:
6113 ret
= io_timeout_remove(req
, issue_flags
);
6115 case IORING_OP_ACCEPT
:
6116 ret
= io_accept(req
, issue_flags
);
6118 case IORING_OP_CONNECT
:
6119 ret
= io_connect(req
, issue_flags
);
6121 case IORING_OP_ASYNC_CANCEL
:
6122 ret
= io_async_cancel(req
, issue_flags
);
6124 case IORING_OP_FALLOCATE
:
6125 ret
= io_fallocate(req
, issue_flags
);
6127 case IORING_OP_OPENAT
:
6128 ret
= io_openat(req
, issue_flags
);
6130 case IORING_OP_CLOSE
:
6131 ret
= io_close(req
, issue_flags
);
6133 case IORING_OP_FILES_UPDATE
:
6134 ret
= io_files_update(req
, issue_flags
);
6136 case IORING_OP_STATX
:
6137 ret
= io_statx(req
, issue_flags
);
6139 case IORING_OP_FADVISE
:
6140 ret
= io_fadvise(req
, issue_flags
);
6142 case IORING_OP_MADVISE
:
6143 ret
= io_madvise(req
, issue_flags
);
6145 case IORING_OP_OPENAT2
:
6146 ret
= io_openat2(req
, issue_flags
);
6148 case IORING_OP_EPOLL_CTL
:
6149 ret
= io_epoll_ctl(req
, issue_flags
);
6151 case IORING_OP_SPLICE
:
6152 ret
= io_splice(req
, issue_flags
);
6154 case IORING_OP_PROVIDE_BUFFERS
:
6155 ret
= io_provide_buffers(req
, issue_flags
);
6157 case IORING_OP_REMOVE_BUFFERS
:
6158 ret
= io_remove_buffers(req
, issue_flags
);
6161 ret
= io_tee(req
, issue_flags
);
6163 case IORING_OP_SHUTDOWN
:
6164 ret
= io_shutdown(req
, issue_flags
);
6166 case IORING_OP_RENAMEAT
:
6167 ret
= io_renameat(req
, issue_flags
);
6169 case IORING_OP_UNLINKAT
:
6170 ret
= io_unlinkat(req
, issue_flags
);
6178 revert_creds(creds
);
6183 /* If the op doesn't have a file, we're not polling for it */
6184 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
6185 const bool in_async
= io_wq_current_is_worker();
6187 /* workqueue context doesn't hold uring_lock, grab it now */
6189 mutex_lock(&ctx
->uring_lock
);
6191 io_iopoll_req_issued(req
, in_async
);
6194 mutex_unlock(&ctx
->uring_lock
);
6200 static void io_wq_submit_work(struct io_wq_work
*work
)
6202 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6203 struct io_kiocb
*timeout
;
6206 timeout
= io_prep_linked_timeout(req
);
6208 io_queue_linked_timeout(timeout
);
6210 if (work
->flags
& IO_WQ_WORK_CANCEL
)
6215 ret
= io_issue_sqe(req
, 0);
6217 * We can get EAGAIN for polled IO even though we're
6218 * forcing a sync submission from here, since we can't
6219 * wait for request slots on the block side.
6227 /* avoid locking problems by failing it from a clean context */
6229 /* io-wq is going to take one down */
6231 io_req_task_queue_fail(req
, ret
);
6235 #define FFS_ASYNC_READ 0x1UL
6236 #define FFS_ASYNC_WRITE 0x2UL
6238 #define FFS_ISREG 0x4UL
6240 #define FFS_ISREG 0x0UL
6242 #define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
6244 static inline struct io_fixed_file
*io_fixed_file_slot(struct io_file_table
*table
,
6247 struct io_fixed_file
*table_l2
;
6249 table_l2
= table
->files
[i
>> IORING_FILE_TABLE_SHIFT
];
6250 return &table_l2
[i
& IORING_FILE_TABLE_MASK
];
6253 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6256 struct io_fixed_file
*slot
= io_fixed_file_slot(&ctx
->file_table
, index
);
6258 return (struct file
*) (slot
->file_ptr
& FFS_MASK
);
6261 static void io_fixed_file_set(struct io_fixed_file
*file_slot
, struct file
*file
)
6263 unsigned long file_ptr
= (unsigned long) file
;
6265 if (__io_file_supports_async(file
, READ
))
6266 file_ptr
|= FFS_ASYNC_READ
;
6267 if (__io_file_supports_async(file
, WRITE
))
6268 file_ptr
|= FFS_ASYNC_WRITE
;
6269 if (S_ISREG(file_inode(file
)->i_mode
))
6270 file_ptr
|= FFS_ISREG
;
6271 file_slot
->file_ptr
= file_ptr
;
6274 static struct file
*io_file_get(struct io_submit_state
*state
,
6275 struct io_kiocb
*req
, int fd
, bool fixed
)
6277 struct io_ring_ctx
*ctx
= req
->ctx
;
6281 unsigned long file_ptr
;
6283 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6285 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6286 file_ptr
= io_fixed_file_slot(&ctx
->file_table
, fd
)->file_ptr
;
6287 file
= (struct file
*) (file_ptr
& FFS_MASK
);
6288 file_ptr
&= ~FFS_MASK
;
6289 /* mask in overlapping REQ_F and FFS bits */
6290 req
->flags
|= (file_ptr
<< REQ_F_ASYNC_READ_BIT
);
6291 io_req_set_rsrc_node(req
);
6293 trace_io_uring_file_get(ctx
, fd
);
6294 file
= __io_file_get(state
, fd
);
6296 /* we don't allow fixed io_uring files */
6297 if (file
&& unlikely(file
->f_op
== &io_uring_fops
))
6298 io_req_track_inflight(req
);
6304 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6306 struct io_timeout_data
*data
= container_of(timer
,
6307 struct io_timeout_data
, timer
);
6308 struct io_kiocb
*prev
, *req
= data
->req
;
6309 struct io_ring_ctx
*ctx
= req
->ctx
;
6310 unsigned long flags
;
6312 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6313 prev
= req
->timeout
.head
;
6314 req
->timeout
.head
= NULL
;
6317 * We don't expect the list to be empty, that will only happen if we
6318 * race with the completion of the linked work.
6320 if (prev
&& req_ref_inc_not_zero(prev
))
6321 io_remove_next_linked(prev
);
6324 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6327 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6328 io_put_req_deferred(prev
, 1);
6330 io_req_complete_post(req
, -ETIME
, 0);
6332 io_put_req_deferred(req
, 1);
6333 return HRTIMER_NORESTART
;
6336 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6338 struct io_ring_ctx
*ctx
= req
->ctx
;
6340 spin_lock_irq(&ctx
->completion_lock
);
6342 * If the back reference is NULL, then our linked request finished
6343 * before we got a chance to setup the timer
6345 if (req
->timeout
.head
) {
6346 struct io_timeout_data
*data
= req
->async_data
;
6348 data
->timer
.function
= io_link_timeout_fn
;
6349 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6352 spin_unlock_irq(&ctx
->completion_lock
);
6353 /* drop submission reference */
6357 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6359 struct io_kiocb
*nxt
= req
->link
;
6361 if (!nxt
|| (req
->flags
& REQ_F_LINK_TIMEOUT
) ||
6362 nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6365 nxt
->timeout
.head
= req
;
6366 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6367 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6371 static void __io_queue_sqe(struct io_kiocb
*req
)
6373 struct io_kiocb
*linked_timeout
= io_prep_linked_timeout(req
);
6376 ret
= io_issue_sqe(req
, IO_URING_F_NONBLOCK
|IO_URING_F_COMPLETE_DEFER
);
6379 * We async punt it if the file wasn't marked NOWAIT, or if the file
6380 * doesn't support non-blocking read/write attempts
6383 /* drop submission reference */
6384 if (req
->flags
& REQ_F_COMPLETE_INLINE
) {
6385 struct io_ring_ctx
*ctx
= req
->ctx
;
6386 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
6388 cs
->reqs
[cs
->nr
++] = req
;
6389 if (cs
->nr
== ARRAY_SIZE(cs
->reqs
))
6390 io_submit_flush_completions(cs
, ctx
);
6394 } else if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6395 if (!io_arm_poll_handler(req
)) {
6397 * Queued up for async execution, worker will release
6398 * submit reference when the iocb is actually submitted.
6400 io_queue_async_work(req
);
6403 io_req_complete_failed(req
, ret
);
6406 io_queue_linked_timeout(linked_timeout
);
6409 static void io_queue_sqe(struct io_kiocb
*req
)
6413 ret
= io_req_defer(req
);
6415 if (ret
!= -EIOCBQUEUED
) {
6417 io_req_complete_failed(req
, ret
);
6419 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6420 ret
= io_req_prep_async(req
);
6423 io_queue_async_work(req
);
6425 __io_queue_sqe(req
);
6430 * Check SQE restrictions (opcode and flags).
6432 * Returns 'true' if SQE is allowed, 'false' otherwise.
6434 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6435 struct io_kiocb
*req
,
6436 unsigned int sqe_flags
)
6438 if (!ctx
->restricted
)
6441 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6444 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6445 ctx
->restrictions
.sqe_flags_required
)
6448 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6449 ctx
->restrictions
.sqe_flags_required
))
6455 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6456 const struct io_uring_sqe
*sqe
)
6458 struct io_submit_state
*state
;
6459 unsigned int sqe_flags
;
6460 int personality
, ret
= 0;
6462 req
->opcode
= READ_ONCE(sqe
->opcode
);
6463 /* same numerical values with corresponding REQ_F_*, safe to copy */
6464 req
->flags
= sqe_flags
= READ_ONCE(sqe
->flags
);
6465 req
->user_data
= READ_ONCE(sqe
->user_data
);
6466 req
->async_data
= NULL
;
6470 req
->fixed_rsrc_refs
= NULL
;
6471 /* one is dropped after submission, the other at completion */
6472 atomic_set(&req
->refs
, 2);
6473 req
->task
= current
;
6475 req
->work
.creds
= NULL
;
6477 /* enforce forwards compatibility on users */
6478 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
)) {
6483 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6486 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6489 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6490 !io_op_defs
[req
->opcode
].buffer_select
)
6493 personality
= READ_ONCE(sqe
->personality
);
6495 req
->work
.creds
= xa_load(&ctx
->personalities
, personality
);
6496 if (!req
->work
.creds
)
6498 get_cred(req
->work
.creds
);
6500 state
= &ctx
->submit_state
;
6503 * Plug now if we have more than 1 IO left after this, and the target
6504 * is potentially a read/write to block based storage.
6506 if (!state
->plug_started
&& state
->ios_left
> 1 &&
6507 io_op_defs
[req
->opcode
].plug
) {
6508 blk_start_plug(&state
->plug
);
6509 state
->plug_started
= true;
6512 if (io_op_defs
[req
->opcode
].needs_file
) {
6513 bool fixed
= req
->flags
& REQ_F_FIXED_FILE
;
6515 req
->file
= io_file_get(state
, req
, READ_ONCE(sqe
->fd
), fixed
);
6516 if (unlikely(!req
->file
))
6524 static int io_submit_sqe(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6525 const struct io_uring_sqe
*sqe
)
6527 struct io_submit_link
*link
= &ctx
->submit_state
.link
;
6530 ret
= io_init_req(ctx
, req
, sqe
);
6531 if (unlikely(ret
)) {
6534 /* fail even hard links since we don't submit */
6535 link
->head
->flags
|= REQ_F_FAIL_LINK
;
6536 io_req_complete_failed(link
->head
, -ECANCELED
);
6539 io_req_complete_failed(req
, ret
);
6542 ret
= io_req_prep(req
, sqe
);
6546 /* don't need @sqe from now on */
6547 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6548 true, ctx
->flags
& IORING_SETUP_SQPOLL
);
6551 * If we already have a head request, queue this one for async
6552 * submittal once the head completes. If we don't have a head but
6553 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6554 * submitted sync once the chain is complete. If none of those
6555 * conditions are true (normal request), then just queue it.
6558 struct io_kiocb
*head
= link
->head
;
6561 * Taking sequential execution of a link, draining both sides
6562 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6563 * requests in the link. So, it drains the head and the
6564 * next after the link request. The last one is done via
6565 * drain_next flag to persist the effect across calls.
6567 if (req
->flags
& REQ_F_IO_DRAIN
) {
6568 head
->flags
|= REQ_F_IO_DRAIN
;
6569 ctx
->drain_next
= 1;
6571 ret
= io_req_prep_async(req
);
6574 trace_io_uring_link(ctx
, req
, head
);
6575 link
->last
->link
= req
;
6578 /* last request of a link, enqueue the link */
6579 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6584 if (unlikely(ctx
->drain_next
)) {
6585 req
->flags
|= REQ_F_IO_DRAIN
;
6586 ctx
->drain_next
= 0;
6588 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6600 * Batched submission is done, ensure local IO is flushed out.
6602 static void io_submit_state_end(struct io_submit_state
*state
,
6603 struct io_ring_ctx
*ctx
)
6605 if (state
->link
.head
)
6606 io_queue_sqe(state
->link
.head
);
6608 io_submit_flush_completions(&state
->comp
, ctx
);
6609 if (state
->plug_started
)
6610 blk_finish_plug(&state
->plug
);
6611 io_state_file_put(state
);
6615 * Start submission side cache.
6617 static void io_submit_state_start(struct io_submit_state
*state
,
6618 unsigned int max_ios
)
6620 state
->plug_started
= false;
6621 state
->ios_left
= max_ios
;
6622 /* set only head, no need to init link_last in advance */
6623 state
->link
.head
= NULL
;
6626 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6628 struct io_rings
*rings
= ctx
->rings
;
6631 * Ensure any loads from the SQEs are done at this point,
6632 * since once we write the new head, the application could
6633 * write new data to them.
6635 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6639 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6640 * that is mapped by userspace. This means that care needs to be taken to
6641 * ensure that reads are stable, as we cannot rely on userspace always
6642 * being a good citizen. If members of the sqe are validated and then later
6643 * used, it's important that those reads are done through READ_ONCE() to
6644 * prevent a re-load down the line.
6646 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6648 u32
*sq_array
= ctx
->sq_array
;
6652 * The cached sq head (or cq tail) serves two purposes:
6654 * 1) allows us to batch the cost of updating the user visible
6656 * 2) allows the kernel side to track the head on its own, even
6657 * though the application is the one updating it.
6659 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
++ & ctx
->sq_mask
]);
6660 if (likely(head
< ctx
->sq_entries
))
6661 return &ctx
->sq_sqes
[head
];
6663 /* drop invalid entries */
6664 ctx
->cached_sq_dropped
++;
6665 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6669 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6673 /* make sure SQ entry isn't read before tail */
6674 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6676 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6679 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6680 refcount_add(nr
, ¤t
->usage
);
6681 io_submit_state_start(&ctx
->submit_state
, nr
);
6683 while (submitted
< nr
) {
6684 const struct io_uring_sqe
*sqe
;
6685 struct io_kiocb
*req
;
6687 req
= io_alloc_req(ctx
);
6688 if (unlikely(!req
)) {
6690 submitted
= -EAGAIN
;
6693 sqe
= io_get_sqe(ctx
);
6694 if (unlikely(!sqe
)) {
6695 kmem_cache_free(req_cachep
, req
);
6698 /* will complete beyond this point, count as submitted */
6700 if (io_submit_sqe(ctx
, req
, sqe
))
6704 if (unlikely(submitted
!= nr
)) {
6705 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6706 struct io_uring_task
*tctx
= current
->io_uring
;
6707 int unused
= nr
- ref_used
;
6709 percpu_ref_put_many(&ctx
->refs
, unused
);
6710 percpu_counter_sub(&tctx
->inflight
, unused
);
6711 put_task_struct_many(current
, unused
);
6714 io_submit_state_end(&ctx
->submit_state
, ctx
);
6715 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6716 io_commit_sqring(ctx
);
6721 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6723 /* Tell userspace we may need a wakeup call */
6724 spin_lock_irq(&ctx
->completion_lock
);
6725 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6726 spin_unlock_irq(&ctx
->completion_lock
);
6729 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6731 spin_lock_irq(&ctx
->completion_lock
);
6732 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6733 spin_unlock_irq(&ctx
->completion_lock
);
6736 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
6738 unsigned int to_submit
;
6741 to_submit
= io_sqring_entries(ctx
);
6742 /* if we're handling multiple rings, cap submit size for fairness */
6743 if (cap_entries
&& to_submit
> 8)
6746 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
6747 unsigned nr_events
= 0;
6749 mutex_lock(&ctx
->uring_lock
);
6750 if (!list_empty(&ctx
->iopoll_list
))
6751 io_do_iopoll(ctx
, &nr_events
, 0);
6753 if (to_submit
&& likely(!percpu_ref_is_dying(&ctx
->refs
)) &&
6754 !(ctx
->flags
& IORING_SETUP_R_DISABLED
))
6755 ret
= io_submit_sqes(ctx
, to_submit
);
6756 mutex_unlock(&ctx
->uring_lock
);
6759 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
6760 wake_up(&ctx
->sqo_sq_wait
);
6765 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
6767 struct io_ring_ctx
*ctx
;
6768 unsigned sq_thread_idle
= 0;
6770 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6771 sq_thread_idle
= max(sq_thread_idle
, ctx
->sq_thread_idle
);
6772 sqd
->sq_thread_idle
= sq_thread_idle
;
6775 static int io_sq_thread(void *data
)
6777 struct io_sq_data
*sqd
= data
;
6778 struct io_ring_ctx
*ctx
;
6779 unsigned long timeout
= 0;
6780 char buf
[TASK_COMM_LEN
];
6783 snprintf(buf
, sizeof(buf
), "iou-sqp-%d", sqd
->task_pid
);
6784 set_task_comm(current
, buf
);
6785 current
->pf_io_worker
= NULL
;
6787 if (sqd
->sq_cpu
!= -1)
6788 set_cpus_allowed_ptr(current
, cpumask_of(sqd
->sq_cpu
));
6790 set_cpus_allowed_ptr(current
, cpu_online_mask
);
6791 current
->flags
|= PF_NO_SETAFFINITY
;
6793 mutex_lock(&sqd
->lock
);
6794 while (!test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
)) {
6796 bool cap_entries
, sqt_spin
, needs_sched
;
6798 if (test_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
) ||
6799 signal_pending(current
)) {
6800 bool did_sig
= false;
6802 mutex_unlock(&sqd
->lock
);
6803 if (signal_pending(current
)) {
6804 struct ksignal ksig
;
6806 did_sig
= get_signal(&ksig
);
6809 mutex_lock(&sqd
->lock
);
6813 io_run_task_work_head(&sqd
->park_task_work
);
6814 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6818 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
6819 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6820 const struct cred
*creds
= NULL
;
6822 if (ctx
->sq_creds
!= current_cred())
6823 creds
= override_creds(ctx
->sq_creds
);
6824 ret
= __io_sq_thread(ctx
, cap_entries
);
6826 revert_creds(creds
);
6827 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
6831 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
6835 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6840 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
6841 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6842 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6843 !list_empty_careful(&ctx
->iopoll_list
)) {
6844 needs_sched
= false;
6847 if (io_sqring_entries(ctx
)) {
6848 needs_sched
= false;
6853 if (needs_sched
&& !test_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
)) {
6854 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6855 io_ring_set_wakeup_flag(ctx
);
6857 mutex_unlock(&sqd
->lock
);
6859 mutex_lock(&sqd
->lock
);
6860 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6861 io_ring_clear_wakeup_flag(ctx
);
6864 finish_wait(&sqd
->wait
, &wait
);
6865 io_run_task_work_head(&sqd
->park_task_work
);
6866 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6869 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6870 io_uring_cancel_sqpoll(ctx
);
6872 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6873 io_ring_set_wakeup_flag(ctx
);
6874 mutex_unlock(&sqd
->lock
);
6877 io_run_task_work_head(&sqd
->park_task_work
);
6878 complete(&sqd
->exited
);
6882 struct io_wait_queue
{
6883 struct wait_queue_entry wq
;
6884 struct io_ring_ctx
*ctx
;
6886 unsigned nr_timeouts
;
6889 static inline bool io_should_wake(struct io_wait_queue
*iowq
)
6891 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6894 * Wake up if we have enough events, or if a timeout occurred since we
6895 * started waiting. For timeouts, we always want to return to userspace,
6896 * regardless of event count.
6898 return io_cqring_events(ctx
) >= iowq
->to_wait
||
6899 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6902 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6903 int wake_flags
, void *key
)
6905 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6909 * Cannot safely flush overflowed CQEs from here, ensure we wake up
6910 * the task, and the next invocation will do it.
6912 if (io_should_wake(iowq
) || test_bit(0, &iowq
->ctx
->cq_check_overflow
))
6913 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6917 static int io_run_task_work_sig(void)
6919 if (io_run_task_work())
6921 if (!signal_pending(current
))
6923 if (test_thread_flag(TIF_NOTIFY_SIGNAL
))
6924 return -ERESTARTSYS
;
6928 /* when returns >0, the caller should retry */
6929 static inline int io_cqring_wait_schedule(struct io_ring_ctx
*ctx
,
6930 struct io_wait_queue
*iowq
,
6931 signed long *timeout
)
6935 /* make sure we run task_work before checking for signals */
6936 ret
= io_run_task_work_sig();
6937 if (ret
|| io_should_wake(iowq
))
6939 /* let the caller flush overflows, retry */
6940 if (test_bit(0, &ctx
->cq_check_overflow
))
6943 *timeout
= schedule_timeout(*timeout
);
6944 return !*timeout
? -ETIME
: 1;
6948 * Wait until events become available, if we don't already have some. The
6949 * application must reap them itself, as they reside on the shared cq ring.
6951 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6952 const sigset_t __user
*sig
, size_t sigsz
,
6953 struct __kernel_timespec __user
*uts
)
6955 struct io_wait_queue iowq
= {
6958 .func
= io_wake_function
,
6959 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6962 .to_wait
= min_events
,
6964 struct io_rings
*rings
= ctx
->rings
;
6965 signed long timeout
= MAX_SCHEDULE_TIMEOUT
;
6969 io_cqring_overflow_flush(ctx
, false);
6970 if (io_cqring_events(ctx
) >= min_events
)
6972 if (!io_run_task_work())
6977 #ifdef CONFIG_COMPAT
6978 if (in_compat_syscall())
6979 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6983 ret
= set_user_sigmask(sig
, sigsz
);
6990 struct timespec64 ts
;
6992 if (get_timespec64(&ts
, uts
))
6994 timeout
= timespec64_to_jiffies(&ts
);
6997 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6998 trace_io_uring_cqring_wait(ctx
, min_events
);
7000 /* if we can't even flush overflow, don't wait for more */
7001 if (!io_cqring_overflow_flush(ctx
, false)) {
7005 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
7006 TASK_INTERRUPTIBLE
);
7007 ret
= io_cqring_wait_schedule(ctx
, &iowq
, &timeout
);
7008 finish_wait(&ctx
->wait
, &iowq
.wq
);
7012 restore_saved_sigmask_unless(ret
== -EINTR
);
7014 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7017 static void io_free_file_tables(struct io_file_table
*table
, unsigned nr_files
)
7019 unsigned i
, nr_tables
= DIV_ROUND_UP(nr_files
, IORING_MAX_FILES_TABLE
);
7021 for (i
= 0; i
< nr_tables
; i
++)
7022 kfree(table
->files
[i
]);
7023 kfree(table
->files
);
7024 table
->files
= NULL
;
7027 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7029 #if defined(CONFIG_UNIX)
7030 if (ctx
->ring_sock
) {
7031 struct sock
*sock
= ctx
->ring_sock
->sk
;
7032 struct sk_buff
*skb
;
7034 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7040 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7043 file
= io_file_from_index(ctx
, i
);
7048 io_free_file_tables(&ctx
->file_table
, ctx
->nr_user_files
);
7049 kfree(ctx
->file_data
);
7050 ctx
->file_data
= NULL
;
7051 ctx
->nr_user_files
= 0;
7054 static inline void io_rsrc_ref_lock(struct io_ring_ctx
*ctx
)
7056 spin_lock_bh(&ctx
->rsrc_ref_lock
);
7059 static inline void io_rsrc_ref_unlock(struct io_ring_ctx
*ctx
)
7061 spin_unlock_bh(&ctx
->rsrc_ref_lock
);
7064 static void io_rsrc_node_destroy(struct io_rsrc_node
*ref_node
)
7066 percpu_ref_exit(&ref_node
->refs
);
7070 static void io_rsrc_node_switch(struct io_ring_ctx
*ctx
,
7071 struct io_rsrc_data
*data_to_kill
)
7073 WARN_ON_ONCE(!ctx
->rsrc_backup_node
);
7074 WARN_ON_ONCE(data_to_kill
&& !ctx
->rsrc_node
);
7077 struct io_rsrc_node
*rsrc_node
= ctx
->rsrc_node
;
7079 rsrc_node
->rsrc_data
= data_to_kill
;
7080 io_rsrc_ref_lock(ctx
);
7081 list_add_tail(&rsrc_node
->node
, &ctx
->rsrc_ref_list
);
7082 io_rsrc_ref_unlock(ctx
);
7084 atomic_inc(&data_to_kill
->refs
);
7085 percpu_ref_kill(&rsrc_node
->refs
);
7086 ctx
->rsrc_node
= NULL
;
7089 if (!ctx
->rsrc_node
) {
7090 ctx
->rsrc_node
= ctx
->rsrc_backup_node
;
7091 ctx
->rsrc_backup_node
= NULL
;
7095 static int io_rsrc_node_switch_start(struct io_ring_ctx
*ctx
)
7097 if (ctx
->rsrc_backup_node
)
7099 ctx
->rsrc_backup_node
= io_rsrc_node_alloc(ctx
);
7100 return ctx
->rsrc_backup_node
? 0 : -ENOMEM
;
7103 static int io_rsrc_ref_quiesce(struct io_rsrc_data
*data
, struct io_ring_ctx
*ctx
)
7107 /* As we may drop ->uring_lock, other task may have started quiesce */
7111 data
->quiesce
= true;
7113 ret
= io_rsrc_node_switch_start(ctx
);
7116 io_rsrc_node_switch(ctx
, data
);
7118 /* kill initial ref, already quiesced if zero */
7119 if (atomic_dec_and_test(&data
->refs
))
7121 flush_delayed_work(&ctx
->rsrc_put_work
);
7122 ret
= wait_for_completion_interruptible(&data
->done
);
7126 atomic_inc(&data
->refs
);
7127 /* wait for all works potentially completing data->done */
7128 flush_delayed_work(&ctx
->rsrc_put_work
);
7129 reinit_completion(&data
->done
);
7131 mutex_unlock(&ctx
->uring_lock
);
7132 ret
= io_run_task_work_sig();
7133 mutex_lock(&ctx
->uring_lock
);
7135 data
->quiesce
= false;
7140 static struct io_rsrc_data
*io_rsrc_data_alloc(struct io_ring_ctx
*ctx
,
7141 rsrc_put_fn
*do_put
)
7143 struct io_rsrc_data
*data
;
7145 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
7149 atomic_set(&data
->refs
, 1);
7151 data
->do_put
= do_put
;
7152 init_completion(&data
->done
);
7156 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7160 if (!ctx
->file_data
)
7162 ret
= io_rsrc_ref_quiesce(ctx
->file_data
, ctx
);
7164 __io_sqe_files_unregister(ctx
);
7168 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7169 __releases(&sqd
->lock
)
7171 WARN_ON_ONCE(sqd
->thread
== current
);
7174 * Do the dance but not conditional clear_bit() because it'd race with
7175 * other threads incrementing park_pending and setting the bit.
7177 clear_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7178 if (atomic_dec_return(&sqd
->park_pending
))
7179 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7180 mutex_unlock(&sqd
->lock
);
7183 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7184 __acquires(&sqd
->lock
)
7186 WARN_ON_ONCE(sqd
->thread
== current
);
7188 atomic_inc(&sqd
->park_pending
);
7189 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7190 mutex_lock(&sqd
->lock
);
7192 wake_up_process(sqd
->thread
);
7195 static void io_sq_thread_stop(struct io_sq_data
*sqd
)
7197 WARN_ON_ONCE(sqd
->thread
== current
);
7198 WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
));
7200 set_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
);
7201 mutex_lock(&sqd
->lock
);
7203 wake_up_process(sqd
->thread
);
7204 mutex_unlock(&sqd
->lock
);
7205 wait_for_completion(&sqd
->exited
);
7208 static void io_put_sq_data(struct io_sq_data
*sqd
)
7210 if (refcount_dec_and_test(&sqd
->refs
)) {
7211 WARN_ON_ONCE(atomic_read(&sqd
->park_pending
));
7213 io_sq_thread_stop(sqd
);
7218 static void io_sq_thread_finish(struct io_ring_ctx
*ctx
)
7220 struct io_sq_data
*sqd
= ctx
->sq_data
;
7223 io_sq_thread_park(sqd
);
7224 list_del_init(&ctx
->sqd_list
);
7225 io_sqd_update_thread_idle(sqd
);
7226 io_sq_thread_unpark(sqd
);
7228 io_put_sq_data(sqd
);
7229 ctx
->sq_data
= NULL
;
7231 put_cred(ctx
->sq_creds
);
7235 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7237 struct io_ring_ctx
*ctx_attach
;
7238 struct io_sq_data
*sqd
;
7241 f
= fdget(p
->wq_fd
);
7243 return ERR_PTR(-ENXIO
);
7244 if (f
.file
->f_op
!= &io_uring_fops
) {
7246 return ERR_PTR(-EINVAL
);
7249 ctx_attach
= f
.file
->private_data
;
7250 sqd
= ctx_attach
->sq_data
;
7253 return ERR_PTR(-EINVAL
);
7255 if (sqd
->task_tgid
!= current
->tgid
) {
7257 return ERR_PTR(-EPERM
);
7260 refcount_inc(&sqd
->refs
);
7265 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
,
7268 struct io_sq_data
*sqd
;
7271 if (p
->flags
& IORING_SETUP_ATTACH_WQ
) {
7272 sqd
= io_attach_sq_data(p
);
7277 /* fall through for EPERM case, setup new sqd/task */
7278 if (PTR_ERR(sqd
) != -EPERM
)
7282 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7284 return ERR_PTR(-ENOMEM
);
7286 atomic_set(&sqd
->park_pending
, 0);
7287 refcount_set(&sqd
->refs
, 1);
7288 INIT_LIST_HEAD(&sqd
->ctx_list
);
7289 mutex_init(&sqd
->lock
);
7290 init_waitqueue_head(&sqd
->wait
);
7291 init_completion(&sqd
->exited
);
7295 #if defined(CONFIG_UNIX)
7297 * Ensure the UNIX gc is aware of our file set, so we are certain that
7298 * the io_uring can be safely unregistered on process exit, even if we have
7299 * loops in the file referencing.
7301 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7303 struct sock
*sk
= ctx
->ring_sock
->sk
;
7304 struct scm_fp_list
*fpl
;
7305 struct sk_buff
*skb
;
7308 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7312 skb
= alloc_skb(0, GFP_KERNEL
);
7321 fpl
->user
= get_uid(current_user());
7322 for (i
= 0; i
< nr
; i
++) {
7323 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7327 fpl
->fp
[nr_files
] = get_file(file
);
7328 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7333 fpl
->max
= SCM_MAX_FD
;
7334 fpl
->count
= nr_files
;
7335 UNIXCB(skb
).fp
= fpl
;
7336 skb
->destructor
= unix_destruct_scm
;
7337 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7338 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7340 for (i
= 0; i
< nr_files
; i
++)
7351 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7352 * causes regular reference counting to break down. We rely on the UNIX
7353 * garbage collection to take care of this problem for us.
7355 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7357 unsigned left
, total
;
7361 left
= ctx
->nr_user_files
;
7363 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7365 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7369 total
+= this_files
;
7375 while (total
< ctx
->nr_user_files
) {
7376 struct file
*file
= io_file_from_index(ctx
, total
);
7386 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7392 static bool io_alloc_file_tables(struct io_file_table
*table
, unsigned nr_files
)
7394 unsigned i
, nr_tables
= DIV_ROUND_UP(nr_files
, IORING_MAX_FILES_TABLE
);
7396 table
->files
= kcalloc(nr_tables
, sizeof(*table
->files
), GFP_KERNEL
);
7400 for (i
= 0; i
< nr_tables
; i
++) {
7401 unsigned int this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7403 table
->files
[i
] = kcalloc(this_files
, sizeof(*table
->files
[i
]),
7405 if (!table
->files
[i
])
7407 nr_files
-= this_files
;
7413 io_free_file_tables(table
, nr_tables
* IORING_MAX_FILES_TABLE
);
7417 static void io_rsrc_file_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
7419 struct file
*file
= prsrc
->file
;
7420 #if defined(CONFIG_UNIX)
7421 struct sock
*sock
= ctx
->ring_sock
->sk
;
7422 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7423 struct sk_buff
*skb
;
7426 __skb_queue_head_init(&list
);
7429 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7430 * remove this entry and rearrange the file array.
7432 skb
= skb_dequeue(head
);
7434 struct scm_fp_list
*fp
;
7436 fp
= UNIXCB(skb
).fp
;
7437 for (i
= 0; i
< fp
->count
; i
++) {
7440 if (fp
->fp
[i
] != file
)
7443 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7444 left
= fp
->count
- 1 - i
;
7446 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7447 left
* sizeof(struct file
*));
7454 __skb_queue_tail(&list
, skb
);
7464 __skb_queue_tail(&list
, skb
);
7466 skb
= skb_dequeue(head
);
7469 if (skb_peek(&list
)) {
7470 spin_lock_irq(&head
->lock
);
7471 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7472 __skb_queue_tail(head
, skb
);
7473 spin_unlock_irq(&head
->lock
);
7480 static void __io_rsrc_put_work(struct io_rsrc_node
*ref_node
)
7482 struct io_rsrc_data
*rsrc_data
= ref_node
->rsrc_data
;
7483 struct io_ring_ctx
*ctx
= rsrc_data
->ctx
;
7484 struct io_rsrc_put
*prsrc
, *tmp
;
7486 list_for_each_entry_safe(prsrc
, tmp
, &ref_node
->rsrc_list
, list
) {
7487 list_del(&prsrc
->list
);
7488 rsrc_data
->do_put(ctx
, prsrc
);
7492 io_rsrc_node_destroy(ref_node
);
7493 if (atomic_dec_and_test(&rsrc_data
->refs
))
7494 complete(&rsrc_data
->done
);
7497 static void io_rsrc_put_work(struct work_struct
*work
)
7499 struct io_ring_ctx
*ctx
;
7500 struct llist_node
*node
;
7502 ctx
= container_of(work
, struct io_ring_ctx
, rsrc_put_work
.work
);
7503 node
= llist_del_all(&ctx
->rsrc_put_llist
);
7506 struct io_rsrc_node
*ref_node
;
7507 struct llist_node
*next
= node
->next
;
7509 ref_node
= llist_entry(node
, struct io_rsrc_node
, llist
);
7510 __io_rsrc_put_work(ref_node
);
7515 static void io_rsrc_node_ref_zero(struct percpu_ref
*ref
)
7517 struct io_rsrc_node
*node
= container_of(ref
, struct io_rsrc_node
, refs
);
7518 struct io_ring_ctx
*ctx
= node
->rsrc_data
->ctx
;
7519 bool first_add
= false;
7521 io_rsrc_ref_lock(ctx
);
7524 while (!list_empty(&ctx
->rsrc_ref_list
)) {
7525 node
= list_first_entry(&ctx
->rsrc_ref_list
,
7526 struct io_rsrc_node
, node
);
7527 /* recycle ref nodes in order */
7530 list_del(&node
->node
);
7531 first_add
|= llist_add(&node
->llist
, &ctx
->rsrc_put_llist
);
7533 io_rsrc_ref_unlock(ctx
);
7536 mod_delayed_work(system_wq
, &ctx
->rsrc_put_work
, HZ
);
7539 static struct io_rsrc_node
*io_rsrc_node_alloc(struct io_ring_ctx
*ctx
)
7541 struct io_rsrc_node
*ref_node
;
7543 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7547 if (percpu_ref_init(&ref_node
->refs
, io_rsrc_node_ref_zero
,
7552 INIT_LIST_HEAD(&ref_node
->node
);
7553 INIT_LIST_HEAD(&ref_node
->rsrc_list
);
7554 ref_node
->done
= false;
7558 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7561 __s32 __user
*fds
= (__s32 __user
*) arg
;
7565 struct io_rsrc_data
*file_data
;
7571 if (nr_args
> IORING_MAX_FIXED_FILES
)
7573 ret
= io_rsrc_node_switch_start(ctx
);
7577 file_data
= io_rsrc_data_alloc(ctx
, io_rsrc_file_put
);
7580 ctx
->file_data
= file_data
;
7582 if (!io_alloc_file_tables(&ctx
->file_table
, nr_args
))
7585 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7586 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7590 /* allow sparse sets */
7600 * Don't allow io_uring instances to be registered. If UNIX
7601 * isn't enabled, then this causes a reference cycle and this
7602 * instance can never get freed. If UNIX is enabled we'll
7603 * handle it just fine, but there's still no point in allowing
7604 * a ring fd as it doesn't support regular read/write anyway.
7606 if (file
->f_op
== &io_uring_fops
) {
7610 io_fixed_file_set(io_fixed_file_slot(&ctx
->file_table
, i
), file
);
7613 ret
= io_sqe_files_scm(ctx
);
7615 __io_sqe_files_unregister(ctx
);
7619 io_rsrc_node_switch(ctx
, NULL
);
7622 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7623 file
= io_file_from_index(ctx
, i
);
7627 io_free_file_tables(&ctx
->file_table
, nr_args
);
7628 ctx
->nr_user_files
= 0;
7630 kfree(ctx
->file_data
);
7631 ctx
->file_data
= NULL
;
7635 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7638 #if defined(CONFIG_UNIX)
7639 struct sock
*sock
= ctx
->ring_sock
->sk
;
7640 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7641 struct sk_buff
*skb
;
7644 * See if we can merge this file into an existing skb SCM_RIGHTS
7645 * file set. If there's no room, fall back to allocating a new skb
7646 * and filling it in.
7648 spin_lock_irq(&head
->lock
);
7649 skb
= skb_peek(head
);
7651 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7653 if (fpl
->count
< SCM_MAX_FD
) {
7654 __skb_unlink(skb
, head
);
7655 spin_unlock_irq(&head
->lock
);
7656 fpl
->fp
[fpl
->count
] = get_file(file
);
7657 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7659 spin_lock_irq(&head
->lock
);
7660 __skb_queue_head(head
, skb
);
7665 spin_unlock_irq(&head
->lock
);
7672 return __io_sqe_files_scm(ctx
, 1, index
);
7678 static int io_queue_rsrc_removal(struct io_rsrc_data
*data
,
7679 struct io_rsrc_node
*node
, void *rsrc
)
7681 struct io_rsrc_put
*prsrc
;
7683 prsrc
= kzalloc(sizeof(*prsrc
), GFP_KERNEL
);
7688 list_add(&prsrc
->list
, &node
->rsrc_list
);
7692 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7693 struct io_uring_rsrc_update
*up
,
7696 struct io_rsrc_data
*data
= ctx
->file_data
;
7697 struct io_fixed_file
*file_slot
;
7702 bool needs_switch
= false;
7704 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7706 if (done
> ctx
->nr_user_files
)
7708 err
= io_rsrc_node_switch_start(ctx
);
7712 fds
= u64_to_user_ptr(up
->data
);
7713 for (done
= 0; done
< nr_args
; done
++) {
7715 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7719 if (fd
== IORING_REGISTER_FILES_SKIP
)
7722 i
= array_index_nospec(up
->offset
+ done
, ctx
->nr_user_files
);
7723 file_slot
= io_fixed_file_slot(&ctx
->file_table
, i
);
7725 if (file_slot
->file_ptr
) {
7726 file
= (struct file
*)(file_slot
->file_ptr
& FFS_MASK
);
7727 err
= io_queue_rsrc_removal(data
, ctx
->rsrc_node
, file
);
7730 file_slot
->file_ptr
= 0;
7731 needs_switch
= true;
7740 * Don't allow io_uring instances to be registered. If
7741 * UNIX isn't enabled, then this causes a reference
7742 * cycle and this instance can never get freed. If UNIX
7743 * is enabled we'll handle it just fine, but there's
7744 * still no point in allowing a ring fd as it doesn't
7745 * support regular read/write anyway.
7747 if (file
->f_op
== &io_uring_fops
) {
7752 io_fixed_file_set(file_slot
, file
);
7753 err
= io_sqe_file_register(ctx
, file
, i
);
7755 file_slot
->file_ptr
= 0;
7763 io_rsrc_node_switch(ctx
, data
);
7764 return done
? done
: err
;
7767 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7770 struct io_uring_rsrc_update up
;
7772 if (!ctx
->file_data
)
7776 if (copy_from_user(&up
, arg
, sizeof(up
)))
7781 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7784 static struct io_wq_work
*io_free_work(struct io_wq_work
*work
)
7786 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7788 req
= io_put_req_find_next(req
);
7789 return req
? &req
->work
: NULL
;
7792 static struct io_wq
*io_init_wq_offload(struct io_ring_ctx
*ctx
,
7793 struct task_struct
*task
)
7795 struct io_wq_hash
*hash
;
7796 struct io_wq_data data
;
7797 unsigned int concurrency
;
7799 hash
= ctx
->hash_map
;
7801 hash
= kzalloc(sizeof(*hash
), GFP_KERNEL
);
7803 return ERR_PTR(-ENOMEM
);
7804 refcount_set(&hash
->refs
, 1);
7805 init_waitqueue_head(&hash
->wait
);
7806 ctx
->hash_map
= hash
;
7811 data
.free_work
= io_free_work
;
7812 data
.do_work
= io_wq_submit_work
;
7814 /* Do QD, or 4 * CPUS, whatever is smallest */
7815 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7817 return io_wq_create(concurrency
, &data
);
7820 static int io_uring_alloc_task_context(struct task_struct
*task
,
7821 struct io_ring_ctx
*ctx
)
7823 struct io_uring_task
*tctx
;
7826 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
7827 if (unlikely(!tctx
))
7830 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
7831 if (unlikely(ret
)) {
7836 tctx
->io_wq
= io_init_wq_offload(ctx
, task
);
7837 if (IS_ERR(tctx
->io_wq
)) {
7838 ret
= PTR_ERR(tctx
->io_wq
);
7839 percpu_counter_destroy(&tctx
->inflight
);
7845 init_waitqueue_head(&tctx
->wait
);
7847 atomic_set(&tctx
->in_idle
, 0);
7848 atomic_set(&tctx
->inflight_tracked
, 0);
7849 task
->io_uring
= tctx
;
7850 spin_lock_init(&tctx
->task_lock
);
7851 INIT_WQ_LIST(&tctx
->task_list
);
7852 tctx
->task_state
= 0;
7853 init_task_work(&tctx
->task_work
, tctx_task_work
);
7857 void __io_uring_free(struct task_struct
*tsk
)
7859 struct io_uring_task
*tctx
= tsk
->io_uring
;
7861 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
7862 WARN_ON_ONCE(tctx
->io_wq
);
7864 percpu_counter_destroy(&tctx
->inflight
);
7866 tsk
->io_uring
= NULL
;
7869 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
7870 struct io_uring_params
*p
)
7874 /* Retain compatibility with failing for an invalid attach attempt */
7875 if ((ctx
->flags
& (IORING_SETUP_ATTACH_WQ
| IORING_SETUP_SQPOLL
)) ==
7876 IORING_SETUP_ATTACH_WQ
) {
7879 f
= fdget(p
->wq_fd
);
7882 if (f
.file
->f_op
!= &io_uring_fops
) {
7888 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7889 struct task_struct
*tsk
;
7890 struct io_sq_data
*sqd
;
7893 sqd
= io_get_sq_data(p
, &attached
);
7899 ctx
->sq_creds
= get_current_cred();
7901 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
7902 if (!ctx
->sq_thread_idle
)
7903 ctx
->sq_thread_idle
= HZ
;
7906 io_sq_thread_park(sqd
);
7907 list_add(&ctx
->sqd_list
, &sqd
->ctx_list
);
7908 io_sqd_update_thread_idle(sqd
);
7909 /* don't attach to a dying SQPOLL thread, would be racy */
7910 if (attached
&& !sqd
->thread
)
7912 io_sq_thread_unpark(sqd
);
7919 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7920 int cpu
= p
->sq_thread_cpu
;
7923 if (cpu
>= nr_cpu_ids
)
7925 if (!cpu_online(cpu
))
7933 sqd
->task_pid
= current
->pid
;
7934 sqd
->task_tgid
= current
->tgid
;
7935 tsk
= create_io_thread(io_sq_thread
, sqd
, NUMA_NO_NODE
);
7942 ret
= io_uring_alloc_task_context(tsk
, ctx
);
7943 wake_up_new_task(tsk
);
7946 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7947 /* Can't have SQ_AFF without SQPOLL */
7954 io_sq_thread_finish(ctx
);
7957 complete(&ctx
->sq_data
->exited
);
7961 static inline void __io_unaccount_mem(struct user_struct
*user
,
7962 unsigned long nr_pages
)
7964 atomic_long_sub(nr_pages
, &user
->locked_vm
);
7967 static inline int __io_account_mem(struct user_struct
*user
,
7968 unsigned long nr_pages
)
7970 unsigned long page_limit
, cur_pages
, new_pages
;
7972 /* Don't allow more pages than we can safely lock */
7973 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
7976 cur_pages
= atomic_long_read(&user
->locked_vm
);
7977 new_pages
= cur_pages
+ nr_pages
;
7978 if (new_pages
> page_limit
)
7980 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
7981 new_pages
) != cur_pages
);
7986 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
7989 __io_unaccount_mem(ctx
->user
, nr_pages
);
7991 if (ctx
->mm_account
)
7992 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
7995 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8000 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8005 if (ctx
->mm_account
)
8006 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8011 static void io_mem_free(void *ptr
)
8018 page
= virt_to_head_page(ptr
);
8019 if (put_page_testzero(page
))
8020 free_compound_page(page
);
8023 static void *io_mem_alloc(size_t size
)
8025 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8026 __GFP_NORETRY
| __GFP_ACCOUNT
;
8028 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8031 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8034 struct io_rings
*rings
;
8035 size_t off
, sq_array_size
;
8037 off
= struct_size(rings
, cqes
, cq_entries
);
8038 if (off
== SIZE_MAX
)
8042 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8050 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8051 if (sq_array_size
== SIZE_MAX
)
8054 if (check_add_overflow(off
, sq_array_size
, &off
))
8060 static void io_buffer_unmap(struct io_ring_ctx
*ctx
, struct io_mapped_ubuf
*imu
)
8064 for (i
= 0; i
< imu
->nr_bvecs
; i
++)
8065 unpin_user_page(imu
->bvec
[i
].bv_page
);
8066 if (imu
->acct_pages
)
8067 io_unaccount_mem(ctx
, imu
->acct_pages
);
8072 static int io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8076 if (!ctx
->user_bufs
)
8079 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++)
8080 io_buffer_unmap(ctx
, &ctx
->user_bufs
[i
]);
8081 kfree(ctx
->user_bufs
);
8082 ctx
->user_bufs
= NULL
;
8083 ctx
->nr_user_bufs
= 0;
8087 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8088 void __user
*arg
, unsigned index
)
8090 struct iovec __user
*src
;
8092 #ifdef CONFIG_COMPAT
8094 struct compat_iovec __user
*ciovs
;
8095 struct compat_iovec ciov
;
8097 ciovs
= (struct compat_iovec __user
*) arg
;
8098 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8101 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8102 dst
->iov_len
= ciov
.iov_len
;
8106 src
= (struct iovec __user
*) arg
;
8107 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8113 * Not super efficient, but this is just a registration time. And we do cache
8114 * the last compound head, so generally we'll only do a full search if we don't
8117 * We check if the given compound head page has already been accounted, to
8118 * avoid double accounting it. This allows us to account the full size of the
8119 * page, not just the constituent pages of a huge page.
8121 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8122 int nr_pages
, struct page
*hpage
)
8126 /* check current page array */
8127 for (i
= 0; i
< nr_pages
; i
++) {
8128 if (!PageCompound(pages
[i
]))
8130 if (compound_head(pages
[i
]) == hpage
)
8134 /* check previously registered pages */
8135 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8136 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8138 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8139 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8141 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8149 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8150 int nr_pages
, struct io_mapped_ubuf
*imu
,
8151 struct page
**last_hpage
)
8155 for (i
= 0; i
< nr_pages
; i
++) {
8156 if (!PageCompound(pages
[i
])) {
8161 hpage
= compound_head(pages
[i
]);
8162 if (hpage
== *last_hpage
)
8164 *last_hpage
= hpage
;
8165 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8167 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8171 if (!imu
->acct_pages
)
8174 ret
= io_account_mem(ctx
, imu
->acct_pages
);
8176 imu
->acct_pages
= 0;
8180 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, struct iovec
*iov
,
8181 struct io_mapped_ubuf
*imu
,
8182 struct page
**last_hpage
)
8184 struct vm_area_struct
**vmas
= NULL
;
8185 struct page
**pages
= NULL
;
8186 unsigned long off
, start
, end
, ubuf
;
8188 int ret
, pret
, nr_pages
, i
;
8190 ubuf
= (unsigned long) iov
->iov_base
;
8191 end
= (ubuf
+ iov
->iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8192 start
= ubuf
>> PAGE_SHIFT
;
8193 nr_pages
= end
- start
;
8197 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*), GFP_KERNEL
);
8201 vmas
= kvmalloc_array(nr_pages
, sizeof(struct vm_area_struct
*),
8206 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8212 mmap_read_lock(current
->mm
);
8213 pret
= pin_user_pages(ubuf
, nr_pages
, FOLL_WRITE
| FOLL_LONGTERM
,
8215 if (pret
== nr_pages
) {
8216 /* don't support file backed memory */
8217 for (i
= 0; i
< nr_pages
; i
++) {
8218 struct vm_area_struct
*vma
= vmas
[i
];
8221 !is_file_hugepages(vma
->vm_file
)) {
8227 ret
= pret
< 0 ? pret
: -EFAULT
;
8229 mmap_read_unlock(current
->mm
);
8232 * if we did partial map, or found file backed vmas,
8233 * release any pages we did get
8236 unpin_user_pages(pages
, pret
);
8241 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, last_hpage
);
8243 unpin_user_pages(pages
, pret
);
8248 off
= ubuf
& ~PAGE_MASK
;
8249 size
= iov
->iov_len
;
8250 for (i
= 0; i
< nr_pages
; i
++) {
8253 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8254 imu
->bvec
[i
].bv_page
= pages
[i
];
8255 imu
->bvec
[i
].bv_len
= vec_len
;
8256 imu
->bvec
[i
].bv_offset
= off
;
8260 /* store original address for later verification */
8262 imu
->ubuf_end
= ubuf
+ iov
->iov_len
;
8263 imu
->nr_bvecs
= nr_pages
;
8271 static int io_buffers_map_alloc(struct io_ring_ctx
*ctx
, unsigned int nr_args
)
8273 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(*ctx
->user_bufs
), GFP_KERNEL
);
8274 return ctx
->user_bufs
? 0 : -ENOMEM
;
8277 static int io_buffer_validate(struct iovec
*iov
)
8279 unsigned long tmp
, acct_len
= iov
->iov_len
+ (PAGE_SIZE
- 1);
8282 * Don't impose further limits on the size and buffer
8283 * constraints here, we'll -EINVAL later when IO is
8284 * submitted if they are wrong.
8286 if (!iov
->iov_base
|| !iov
->iov_len
)
8289 /* arbitrary limit, but we need something */
8290 if (iov
->iov_len
> SZ_1G
)
8293 if (check_add_overflow((unsigned long)iov
->iov_base
, acct_len
, &tmp
))
8299 static int io_sqe_buffers_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8300 unsigned int nr_args
)
8304 struct page
*last_hpage
= NULL
;
8308 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8310 ret
= io_buffers_map_alloc(ctx
, nr_args
);
8314 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_bufs
++) {
8315 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8317 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8320 ret
= io_buffer_validate(&iov
);
8323 ret
= io_sqe_buffer_register(ctx
, &iov
, imu
, &last_hpage
);
8329 io_sqe_buffers_unregister(ctx
);
8334 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8336 __s32 __user
*fds
= arg
;
8342 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8345 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8346 if (IS_ERR(ctx
->cq_ev_fd
)) {
8347 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8348 ctx
->cq_ev_fd
= NULL
;
8355 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8357 if (ctx
->cq_ev_fd
) {
8358 eventfd_ctx_put(ctx
->cq_ev_fd
);
8359 ctx
->cq_ev_fd
= NULL
;
8366 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8368 struct io_buffer
*buf
;
8369 unsigned long index
;
8371 xa_for_each(&ctx
->io_buffers
, index
, buf
)
8372 __io_remove_buffers(ctx
, buf
, index
, -1U);
8375 static void io_req_cache_free(struct list_head
*list
, struct task_struct
*tsk
)
8377 struct io_kiocb
*req
, *nxt
;
8379 list_for_each_entry_safe(req
, nxt
, list
, compl.list
) {
8380 if (tsk
&& req
->task
!= tsk
)
8382 list_del(&req
->compl.list
);
8383 kmem_cache_free(req_cachep
, req
);
8387 static void io_req_caches_free(struct io_ring_ctx
*ctx
)
8389 struct io_submit_state
*submit_state
= &ctx
->submit_state
;
8390 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
8392 mutex_lock(&ctx
->uring_lock
);
8394 if (submit_state
->free_reqs
) {
8395 kmem_cache_free_bulk(req_cachep
, submit_state
->free_reqs
,
8396 submit_state
->reqs
);
8397 submit_state
->free_reqs
= 0;
8400 io_flush_cached_locked_reqs(ctx
, cs
);
8401 io_req_cache_free(&cs
->free_list
, NULL
);
8402 mutex_unlock(&ctx
->uring_lock
);
8405 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8407 io_sq_thread_finish(ctx
);
8408 io_sqe_buffers_unregister(ctx
);
8410 if (ctx
->mm_account
) {
8411 mmdrop(ctx
->mm_account
);
8412 ctx
->mm_account
= NULL
;
8415 mutex_lock(&ctx
->uring_lock
);
8416 if (ctx
->file_data
) {
8417 if (!atomic_dec_and_test(&ctx
->file_data
->refs
))
8418 wait_for_completion(&ctx
->file_data
->done
);
8419 __io_sqe_files_unregister(ctx
);
8422 __io_cqring_overflow_flush(ctx
, true);
8423 mutex_unlock(&ctx
->uring_lock
);
8424 io_eventfd_unregister(ctx
);
8425 io_destroy_buffers(ctx
);
8427 /* there are no registered resources left, nobody uses it */
8429 io_rsrc_node_destroy(ctx
->rsrc_node
);
8430 if (ctx
->rsrc_backup_node
)
8431 io_rsrc_node_destroy(ctx
->rsrc_backup_node
);
8432 flush_delayed_work(&ctx
->rsrc_put_work
);
8434 WARN_ON_ONCE(!list_empty(&ctx
->rsrc_ref_list
));
8435 WARN_ON_ONCE(!llist_empty(&ctx
->rsrc_put_llist
));
8437 #if defined(CONFIG_UNIX)
8438 if (ctx
->ring_sock
) {
8439 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8440 sock_release(ctx
->ring_sock
);
8444 io_mem_free(ctx
->rings
);
8445 io_mem_free(ctx
->sq_sqes
);
8447 percpu_ref_exit(&ctx
->refs
);
8448 free_uid(ctx
->user
);
8449 io_req_caches_free(ctx
);
8451 io_wq_put_hash(ctx
->hash_map
);
8452 kfree(ctx
->cancel_hash
);
8456 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8458 struct io_ring_ctx
*ctx
= file
->private_data
;
8461 poll_wait(file
, &ctx
->cq_wait
, wait
);
8463 * synchronizes with barrier from wq_has_sleeper call in
8467 if (!io_sqring_full(ctx
))
8468 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8471 * Don't flush cqring overflow list here, just do a simple check.
8472 * Otherwise there could possible be ABBA deadlock:
8475 * lock(&ctx->uring_lock);
8477 * lock(&ctx->uring_lock);
8480 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
8481 * pushs them to do the flush.
8483 if (io_cqring_events(ctx
) || test_bit(0, &ctx
->cq_check_overflow
))
8484 mask
|= EPOLLIN
| EPOLLRDNORM
;
8489 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8491 struct io_ring_ctx
*ctx
= file
->private_data
;
8493 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8496 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
8498 const struct cred
*creds
;
8500 creds
= xa_erase(&ctx
->personalities
, id
);
8509 static inline bool io_run_ctx_fallback(struct io_ring_ctx
*ctx
)
8511 return io_run_task_work_head(&ctx
->exit_task_work
);
8514 struct io_tctx_exit
{
8515 struct callback_head task_work
;
8516 struct completion completion
;
8517 struct io_ring_ctx
*ctx
;
8520 static void io_tctx_exit_cb(struct callback_head
*cb
)
8522 struct io_uring_task
*tctx
= current
->io_uring
;
8523 struct io_tctx_exit
*work
;
8525 work
= container_of(cb
, struct io_tctx_exit
, task_work
);
8527 * When @in_idle, we're in cancellation and it's racy to remove the
8528 * node. It'll be removed by the end of cancellation, just ignore it.
8530 if (!atomic_read(&tctx
->in_idle
))
8531 io_uring_del_task_file((unsigned long)work
->ctx
);
8532 complete(&work
->completion
);
8535 static void io_ring_exit_work(struct work_struct
*work
)
8537 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
, exit_work
);
8538 unsigned long timeout
= jiffies
+ HZ
* 60 * 5;
8539 struct io_tctx_exit exit
;
8540 struct io_tctx_node
*node
;
8543 /* prevent SQPOLL from submitting new requests */
8545 io_sq_thread_park(ctx
->sq_data
);
8546 list_del_init(&ctx
->sqd_list
);
8547 io_sqd_update_thread_idle(ctx
->sq_data
);
8548 io_sq_thread_unpark(ctx
->sq_data
);
8552 * If we're doing polled IO and end up having requests being
8553 * submitted async (out-of-line), then completions can come in while
8554 * we're waiting for refs to drop. We need to reap these manually,
8555 * as nobody else will be looking for them.
8558 io_uring_try_cancel_requests(ctx
, NULL
, NULL
);
8560 WARN_ON_ONCE(time_after(jiffies
, timeout
));
8561 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8563 init_completion(&exit
.completion
);
8564 init_task_work(&exit
.task_work
, io_tctx_exit_cb
);
8567 * Some may use context even when all refs and requests have been put,
8568 * and they are free to do so while still holding uring_lock or
8569 * completion_lock, see __io_req_task_submit(). Apart from other work,
8570 * this lock/unlock section also waits them to finish.
8572 mutex_lock(&ctx
->uring_lock
);
8573 while (!list_empty(&ctx
->tctx_list
)) {
8574 WARN_ON_ONCE(time_after(jiffies
, timeout
));
8576 node
= list_first_entry(&ctx
->tctx_list
, struct io_tctx_node
,
8578 /* don't spin on a single task if cancellation failed */
8579 list_rotate_left(&ctx
->tctx_list
);
8580 ret
= task_work_add(node
->task
, &exit
.task_work
, TWA_SIGNAL
);
8581 if (WARN_ON_ONCE(ret
))
8583 wake_up_process(node
->task
);
8585 mutex_unlock(&ctx
->uring_lock
);
8586 wait_for_completion(&exit
.completion
);
8587 mutex_lock(&ctx
->uring_lock
);
8589 mutex_unlock(&ctx
->uring_lock
);
8590 spin_lock_irq(&ctx
->completion_lock
);
8591 spin_unlock_irq(&ctx
->completion_lock
);
8593 io_ring_ctx_free(ctx
);
8596 /* Returns true if we found and killed one or more timeouts */
8597 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
8598 struct files_struct
*files
)
8600 struct io_kiocb
*req
, *tmp
;
8603 spin_lock_irq(&ctx
->completion_lock
);
8604 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
8605 if (io_match_task(req
, tsk
, files
)) {
8606 io_kill_timeout(req
, -ECANCELED
);
8611 io_commit_cqring(ctx
);
8612 spin_unlock_irq(&ctx
->completion_lock
);
8614 io_cqring_ev_posted(ctx
);
8615 return canceled
!= 0;
8618 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8620 unsigned long index
;
8621 struct creds
*creds
;
8623 mutex_lock(&ctx
->uring_lock
);
8624 percpu_ref_kill(&ctx
->refs
);
8626 __io_cqring_overflow_flush(ctx
, true);
8627 xa_for_each(&ctx
->personalities
, index
, creds
)
8628 io_unregister_personality(ctx
, index
);
8629 mutex_unlock(&ctx
->uring_lock
);
8631 io_kill_timeouts(ctx
, NULL
, NULL
);
8632 io_poll_remove_all(ctx
, NULL
, NULL
);
8634 /* if we failed setting up the ctx, we might not have any rings */
8635 io_iopoll_try_reap_events(ctx
);
8637 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8639 * Use system_unbound_wq to avoid spawning tons of event kworkers
8640 * if we're exiting a ton of rings at the same time. It just adds
8641 * noise and overhead, there's no discernable change in runtime
8642 * over using system_wq.
8644 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8647 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8649 struct io_ring_ctx
*ctx
= file
->private_data
;
8651 file
->private_data
= NULL
;
8652 io_ring_ctx_wait_and_kill(ctx
);
8656 struct io_task_cancel
{
8657 struct task_struct
*task
;
8658 struct files_struct
*files
;
8661 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8663 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8664 struct io_task_cancel
*cancel
= data
;
8667 if (cancel
->files
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
8668 unsigned long flags
;
8669 struct io_ring_ctx
*ctx
= req
->ctx
;
8671 /* protect against races with linked timeouts */
8672 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
8673 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8674 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
8676 ret
= io_match_task(req
, cancel
->task
, cancel
->files
);
8681 static bool io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8682 struct task_struct
*task
,
8683 struct files_struct
*files
)
8685 struct io_defer_entry
*de
;
8688 spin_lock_irq(&ctx
->completion_lock
);
8689 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8690 if (io_match_task(de
->req
, task
, files
)) {
8691 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8695 spin_unlock_irq(&ctx
->completion_lock
);
8696 if (list_empty(&list
))
8699 while (!list_empty(&list
)) {
8700 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8701 list_del_init(&de
->list
);
8702 io_req_complete_failed(de
->req
, -ECANCELED
);
8708 static bool io_cancel_ctx_cb(struct io_wq_work
*work
, void *data
)
8710 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8712 return req
->ctx
== data
;
8715 static bool io_uring_try_cancel_iowq(struct io_ring_ctx
*ctx
)
8717 struct io_tctx_node
*node
;
8718 enum io_wq_cancel cret
;
8721 mutex_lock(&ctx
->uring_lock
);
8722 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
8723 struct io_uring_task
*tctx
= node
->task
->io_uring
;
8726 * io_wq will stay alive while we hold uring_lock, because it's
8727 * killed after ctx nodes, which requires to take the lock.
8729 if (!tctx
|| !tctx
->io_wq
)
8731 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_ctx_cb
, ctx
, true);
8732 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
8734 mutex_unlock(&ctx
->uring_lock
);
8739 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
8740 struct task_struct
*task
,
8741 struct files_struct
*files
)
8743 struct io_task_cancel cancel
= { .task
= task
, .files
= files
, };
8744 struct io_uring_task
*tctx
= task
? task
->io_uring
: NULL
;
8747 enum io_wq_cancel cret
;
8751 ret
|= io_uring_try_cancel_iowq(ctx
);
8752 } else if (tctx
&& tctx
->io_wq
) {
8754 * Cancels requests of all rings, not only @ctx, but
8755 * it's fine as the task is in exit/exec.
8757 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_task_cb
,
8759 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
8762 /* SQPOLL thread does its own polling */
8763 if ((!(ctx
->flags
& IORING_SETUP_SQPOLL
) && !files
) ||
8764 (ctx
->sq_data
&& ctx
->sq_data
->thread
== current
)) {
8765 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8766 io_iopoll_try_reap_events(ctx
);
8771 ret
|= io_cancel_defer_files(ctx
, task
, files
);
8772 ret
|= io_poll_remove_all(ctx
, task
, files
);
8773 ret
|= io_kill_timeouts(ctx
, task
, files
);
8774 ret
|= io_run_task_work();
8775 ret
|= io_run_ctx_fallback(ctx
);
8782 static int __io_uring_add_task_file(struct io_ring_ctx
*ctx
)
8784 struct io_uring_task
*tctx
= current
->io_uring
;
8785 struct io_tctx_node
*node
;
8788 if (unlikely(!tctx
)) {
8789 ret
= io_uring_alloc_task_context(current
, ctx
);
8792 tctx
= current
->io_uring
;
8794 if (!xa_load(&tctx
->xa
, (unsigned long)ctx
)) {
8795 node
= kmalloc(sizeof(*node
), GFP_KERNEL
);
8799 node
->task
= current
;
8801 ret
= xa_err(xa_store(&tctx
->xa
, (unsigned long)ctx
,
8808 mutex_lock(&ctx
->uring_lock
);
8809 list_add(&node
->ctx_node
, &ctx
->tctx_list
);
8810 mutex_unlock(&ctx
->uring_lock
);
8817 * Note that this task has used io_uring. We use it for cancelation purposes.
8819 static inline int io_uring_add_task_file(struct io_ring_ctx
*ctx
)
8821 struct io_uring_task
*tctx
= current
->io_uring
;
8823 if (likely(tctx
&& tctx
->last
== ctx
))
8825 return __io_uring_add_task_file(ctx
);
8829 * Remove this io_uring_file -> task mapping.
8831 static void io_uring_del_task_file(unsigned long index
)
8833 struct io_uring_task
*tctx
= current
->io_uring
;
8834 struct io_tctx_node
*node
;
8838 node
= xa_erase(&tctx
->xa
, index
);
8842 WARN_ON_ONCE(current
!= node
->task
);
8843 WARN_ON_ONCE(list_empty(&node
->ctx_node
));
8845 mutex_lock(&node
->ctx
->uring_lock
);
8846 list_del(&node
->ctx_node
);
8847 mutex_unlock(&node
->ctx
->uring_lock
);
8849 if (tctx
->last
== node
->ctx
)
8854 static void io_uring_clean_tctx(struct io_uring_task
*tctx
)
8856 struct io_tctx_node
*node
;
8857 unsigned long index
;
8859 xa_for_each(&tctx
->xa
, index
, node
)
8860 io_uring_del_task_file(index
);
8862 io_wq_put_and_exit(tctx
->io_wq
);
8867 static s64
tctx_inflight(struct io_uring_task
*tctx
, bool tracked
)
8870 return atomic_read(&tctx
->inflight_tracked
);
8871 return percpu_counter_sum(&tctx
->inflight
);
8874 static void io_sqpoll_cancel_cb(struct callback_head
*cb
)
8876 struct io_tctx_exit
*work
= container_of(cb
, struct io_tctx_exit
, task_work
);
8877 struct io_ring_ctx
*ctx
= work
->ctx
;
8878 struct io_sq_data
*sqd
= ctx
->sq_data
;
8881 io_uring_cancel_sqpoll(ctx
);
8882 complete(&work
->completion
);
8885 static void io_sqpoll_cancel_sync(struct io_ring_ctx
*ctx
)
8887 struct io_sq_data
*sqd
= ctx
->sq_data
;
8888 struct io_tctx_exit work
= { .ctx
= ctx
, };
8889 struct task_struct
*task
;
8891 io_sq_thread_park(sqd
);
8892 list_del_init(&ctx
->sqd_list
);
8893 io_sqd_update_thread_idle(sqd
);
8896 init_completion(&work
.completion
);
8897 init_task_work(&work
.task_work
, io_sqpoll_cancel_cb
);
8898 io_task_work_add_head(&sqd
->park_task_work
, &work
.task_work
);
8899 wake_up_process(task
);
8901 io_sq_thread_unpark(sqd
);
8904 wait_for_completion(&work
.completion
);
8907 static void io_uring_try_cancel(struct files_struct
*files
)
8909 struct io_uring_task
*tctx
= current
->io_uring
;
8910 struct io_tctx_node
*node
;
8911 unsigned long index
;
8913 xa_for_each(&tctx
->xa
, index
, node
) {
8914 struct io_ring_ctx
*ctx
= node
->ctx
;
8917 io_sqpoll_cancel_sync(ctx
);
8920 io_uring_try_cancel_requests(ctx
, current
, files
);
8924 /* should only be called by SQPOLL task */
8925 static void io_uring_cancel_sqpoll(struct io_ring_ctx
*ctx
)
8927 struct io_sq_data
*sqd
= ctx
->sq_data
;
8928 struct io_uring_task
*tctx
= current
->io_uring
;
8932 WARN_ON_ONCE(!sqd
|| ctx
->sq_data
->thread
!= current
);
8934 atomic_inc(&tctx
->in_idle
);
8936 /* read completions before cancelations */
8937 inflight
= tctx_inflight(tctx
, false);
8940 io_uring_try_cancel_requests(ctx
, current
, NULL
);
8942 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
8944 * If we've seen completions, retry without waiting. This
8945 * avoids a race where a completion comes in before we did
8946 * prepare_to_wait().
8948 if (inflight
== tctx_inflight(tctx
, false))
8950 finish_wait(&tctx
->wait
, &wait
);
8952 atomic_dec(&tctx
->in_idle
);
8956 * Find any io_uring fd that this task has registered or done IO on, and cancel
8959 void __io_uring_cancel(struct files_struct
*files
)
8961 struct io_uring_task
*tctx
= current
->io_uring
;
8965 /* make sure overflow events are dropped */
8966 atomic_inc(&tctx
->in_idle
);
8967 io_uring_try_cancel(files
);
8970 /* read completions before cancelations */
8971 inflight
= tctx_inflight(tctx
, !!files
);
8974 io_uring_try_cancel(files
);
8975 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
8978 * If we've seen completions, retry without waiting. This
8979 * avoids a race where a completion comes in before we did
8980 * prepare_to_wait().
8982 if (inflight
== tctx_inflight(tctx
, !!files
))
8984 finish_wait(&tctx
->wait
, &wait
);
8986 atomic_dec(&tctx
->in_idle
);
8988 io_uring_clean_tctx(tctx
);
8990 /* for exec all current's requests should be gone, kill tctx */
8991 __io_uring_free(current
);
8995 static void *io_uring_validate_mmap_request(struct file
*file
,
8996 loff_t pgoff
, size_t sz
)
8998 struct io_ring_ctx
*ctx
= file
->private_data
;
8999 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9004 case IORING_OFF_SQ_RING
:
9005 case IORING_OFF_CQ_RING
:
9008 case IORING_OFF_SQES
:
9012 return ERR_PTR(-EINVAL
);
9015 page
= virt_to_head_page(ptr
);
9016 if (sz
> page_size(page
))
9017 return ERR_PTR(-EINVAL
);
9024 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9026 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9030 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9032 return PTR_ERR(ptr
);
9034 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9035 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9038 #else /* !CONFIG_MMU */
9040 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9042 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9045 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9047 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9050 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9051 unsigned long addr
, unsigned long len
,
9052 unsigned long pgoff
, unsigned long flags
)
9056 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9058 return PTR_ERR(ptr
);
9060 return (unsigned long) ptr
;
9063 #endif /* !CONFIG_MMU */
9065 static int io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9070 if (!io_sqring_full(ctx
))
9072 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9074 if (!io_sqring_full(ctx
))
9077 } while (!signal_pending(current
));
9079 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9083 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9084 struct __kernel_timespec __user
**ts
,
9085 const sigset_t __user
**sig
)
9087 struct io_uring_getevents_arg arg
;
9090 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9091 * is just a pointer to the sigset_t.
9093 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9094 *sig
= (const sigset_t __user
*) argp
;
9100 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9101 * timespec and sigset_t pointers if good.
9103 if (*argsz
!= sizeof(arg
))
9105 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9107 *sig
= u64_to_user_ptr(arg
.sigmask
);
9108 *argsz
= arg
.sigmask_sz
;
9109 *ts
= u64_to_user_ptr(arg
.ts
);
9113 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9114 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9117 struct io_ring_ctx
*ctx
;
9124 if (unlikely(flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9125 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
)))
9129 if (unlikely(!f
.file
))
9133 if (unlikely(f
.file
->f_op
!= &io_uring_fops
))
9137 ctx
= f
.file
->private_data
;
9138 if (unlikely(!percpu_ref_tryget(&ctx
->refs
)))
9142 if (unlikely(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9146 * For SQ polling, the thread will do all submissions and completions.
9147 * Just return the requested submit count, and wake the thread if
9151 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9152 io_cqring_overflow_flush(ctx
, false);
9155 if (unlikely(ctx
->sq_data
->thread
== NULL
)) {
9158 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9159 wake_up(&ctx
->sq_data
->wait
);
9160 if (flags
& IORING_ENTER_SQ_WAIT
) {
9161 ret
= io_sqpoll_wait_sq(ctx
);
9165 submitted
= to_submit
;
9166 } else if (to_submit
) {
9167 ret
= io_uring_add_task_file(ctx
);
9170 mutex_lock(&ctx
->uring_lock
);
9171 submitted
= io_submit_sqes(ctx
, to_submit
);
9172 mutex_unlock(&ctx
->uring_lock
);
9174 if (submitted
!= to_submit
)
9177 if (flags
& IORING_ENTER_GETEVENTS
) {
9178 const sigset_t __user
*sig
;
9179 struct __kernel_timespec __user
*ts
;
9181 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
9185 min_complete
= min(min_complete
, ctx
->cq_entries
);
9188 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9189 * space applications don't need to do io completion events
9190 * polling again, they can rely on io_sq_thread to do polling
9191 * work, which can reduce cpu usage and uring_lock contention.
9193 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
9194 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9195 ret
= io_iopoll_check(ctx
, min_complete
);
9197 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
9202 percpu_ref_put(&ctx
->refs
);
9205 return submitted
? submitted
: ret
;
9208 #ifdef CONFIG_PROC_FS
9209 static int io_uring_show_cred(struct seq_file
*m
, unsigned int id
,
9210 const struct cred
*cred
)
9212 struct user_namespace
*uns
= seq_user_ns(m
);
9213 struct group_info
*gi
;
9218 seq_printf(m
, "%5d\n", id
);
9219 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
9220 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
9221 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
9222 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
9223 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
9224 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
9225 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
9226 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
9227 seq_puts(m
, "\n\tGroups:\t");
9228 gi
= cred
->group_info
;
9229 for (g
= 0; g
< gi
->ngroups
; g
++) {
9230 seq_put_decimal_ull(m
, g
? " " : "",
9231 from_kgid_munged(uns
, gi
->gid
[g
]));
9233 seq_puts(m
, "\n\tCapEff:\t");
9234 cap
= cred
->cap_effective
;
9235 CAP_FOR_EACH_U32(__capi
)
9236 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
9241 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
9243 struct io_sq_data
*sq
= NULL
;
9248 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9249 * since fdinfo case grabs it in the opposite direction of normal use
9250 * cases. If we fail to get the lock, we just don't iterate any
9251 * structures that could be going away outside the io_uring mutex.
9253 has_lock
= mutex_trylock(&ctx
->uring_lock
);
9255 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9261 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
9262 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
9263 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
9264 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
9265 struct file
*f
= io_file_from_index(ctx
, i
);
9268 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
9270 seq_printf(m
, "%5u: <none>\n", i
);
9272 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
9273 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
9274 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
9275 unsigned int len
= buf
->ubuf_end
- buf
->ubuf
;
9277 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
, len
);
9279 if (has_lock
&& !xa_empty(&ctx
->personalities
)) {
9280 unsigned long index
;
9281 const struct cred
*cred
;
9283 seq_printf(m
, "Personalities:\n");
9284 xa_for_each(&ctx
->personalities
, index
, cred
)
9285 io_uring_show_cred(m
, index
, cred
);
9287 seq_printf(m
, "PollList:\n");
9288 spin_lock_irq(&ctx
->completion_lock
);
9289 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9290 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9291 struct io_kiocb
*req
;
9293 hlist_for_each_entry(req
, list
, hash_node
)
9294 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9295 req
->task
->task_works
!= NULL
);
9297 spin_unlock_irq(&ctx
->completion_lock
);
9299 mutex_unlock(&ctx
->uring_lock
);
9302 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9304 struct io_ring_ctx
*ctx
= f
->private_data
;
9306 if (percpu_ref_tryget(&ctx
->refs
)) {
9307 __io_uring_show_fdinfo(ctx
, m
);
9308 percpu_ref_put(&ctx
->refs
);
9313 static const struct file_operations io_uring_fops
= {
9314 .release
= io_uring_release
,
9315 .mmap
= io_uring_mmap
,
9317 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9318 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9320 .poll
= io_uring_poll
,
9321 .fasync
= io_uring_fasync
,
9322 #ifdef CONFIG_PROC_FS
9323 .show_fdinfo
= io_uring_show_fdinfo
,
9327 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9328 struct io_uring_params
*p
)
9330 struct io_rings
*rings
;
9331 size_t size
, sq_array_offset
;
9333 /* make sure these are sane, as we already accounted them */
9334 ctx
->sq_entries
= p
->sq_entries
;
9335 ctx
->cq_entries
= p
->cq_entries
;
9337 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9338 if (size
== SIZE_MAX
)
9341 rings
= io_mem_alloc(size
);
9346 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9347 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9348 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9349 rings
->sq_ring_entries
= p
->sq_entries
;
9350 rings
->cq_ring_entries
= p
->cq_entries
;
9351 ctx
->sq_mask
= rings
->sq_ring_mask
;
9352 ctx
->cq_mask
= rings
->cq_ring_mask
;
9354 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9355 if (size
== SIZE_MAX
) {
9356 io_mem_free(ctx
->rings
);
9361 ctx
->sq_sqes
= io_mem_alloc(size
);
9362 if (!ctx
->sq_sqes
) {
9363 io_mem_free(ctx
->rings
);
9371 static int io_uring_install_fd(struct io_ring_ctx
*ctx
, struct file
*file
)
9375 fd
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9379 ret
= io_uring_add_task_file(ctx
);
9384 fd_install(fd
, file
);
9389 * Allocate an anonymous fd, this is what constitutes the application
9390 * visible backing of an io_uring instance. The application mmaps this
9391 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9392 * we have to tie this fd to a socket for file garbage collection purposes.
9394 static struct file
*io_uring_get_file(struct io_ring_ctx
*ctx
)
9397 #if defined(CONFIG_UNIX)
9400 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9403 return ERR_PTR(ret
);
9406 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9407 O_RDWR
| O_CLOEXEC
);
9408 #if defined(CONFIG_UNIX)
9410 sock_release(ctx
->ring_sock
);
9411 ctx
->ring_sock
= NULL
;
9413 ctx
->ring_sock
->file
= file
;
9419 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9420 struct io_uring_params __user
*params
)
9422 struct io_ring_ctx
*ctx
;
9428 if (entries
> IORING_MAX_ENTRIES
) {
9429 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9431 entries
= IORING_MAX_ENTRIES
;
9435 * Use twice as many entries for the CQ ring. It's possible for the
9436 * application to drive a higher depth than the size of the SQ ring,
9437 * since the sqes are only used at submission time. This allows for
9438 * some flexibility in overcommitting a bit. If the application has
9439 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9440 * of CQ ring entries manually.
9442 p
->sq_entries
= roundup_pow_of_two(entries
);
9443 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9445 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9446 * to a power-of-two, if it isn't already. We do NOT impose
9447 * any cq vs sq ring sizing.
9451 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9452 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9454 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9456 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9457 if (p
->cq_entries
< p
->sq_entries
)
9460 p
->cq_entries
= 2 * p
->sq_entries
;
9463 ctx
= io_ring_ctx_alloc(p
);
9466 ctx
->compat
= in_compat_syscall();
9467 if (!capable(CAP_IPC_LOCK
))
9468 ctx
->user
= get_uid(current_user());
9471 * This is just grabbed for accounting purposes. When a process exits,
9472 * the mm is exited and dropped before the files, hence we need to hang
9473 * on to this mm purely for the purposes of being able to unaccount
9474 * memory (locked/pinned vm). It's not used for anything else.
9476 mmgrab(current
->mm
);
9477 ctx
->mm_account
= current
->mm
;
9479 ret
= io_allocate_scq_urings(ctx
, p
);
9483 ret
= io_sq_offload_create(ctx
, p
);
9487 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9488 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9489 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9490 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9491 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9492 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9493 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9494 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9496 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9497 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9498 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9499 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9500 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9501 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9502 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9503 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9505 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9506 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9507 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9508 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
9509 IORING_FEAT_EXT_ARG
| IORING_FEAT_NATIVE_WORKERS
;
9511 if (copy_to_user(params
, p
, sizeof(*p
))) {
9516 file
= io_uring_get_file(ctx
);
9518 ret
= PTR_ERR(file
);
9523 * Install ring fd as the very last thing, so we don't risk someone
9524 * having closed it before we finish setup
9526 ret
= io_uring_install_fd(ctx
, file
);
9528 /* fput will clean it up */
9533 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9536 io_ring_ctx_wait_and_kill(ctx
);
9541 * Sets up an aio uring context, and returns the fd. Applications asks for a
9542 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9543 * params structure passed in.
9545 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9547 struct io_uring_params p
;
9550 if (copy_from_user(&p
, params
, sizeof(p
)))
9552 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9557 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9558 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9559 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9560 IORING_SETUP_R_DISABLED
))
9563 return io_uring_create(entries
, &p
, params
);
9566 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9567 struct io_uring_params __user
*, params
)
9569 return io_uring_setup(entries
, params
);
9572 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9574 struct io_uring_probe
*p
;
9578 size
= struct_size(p
, ops
, nr_args
);
9579 if (size
== SIZE_MAX
)
9581 p
= kzalloc(size
, GFP_KERNEL
);
9586 if (copy_from_user(p
, arg
, size
))
9589 if (memchr_inv(p
, 0, size
))
9592 p
->last_op
= IORING_OP_LAST
- 1;
9593 if (nr_args
> IORING_OP_LAST
)
9594 nr_args
= IORING_OP_LAST
;
9596 for (i
= 0; i
< nr_args
; i
++) {
9598 if (!io_op_defs
[i
].not_supported
)
9599 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9604 if (copy_to_user(arg
, p
, size
))
9611 static int io_register_personality(struct io_ring_ctx
*ctx
)
9613 const struct cred
*creds
;
9617 creds
= get_current_cred();
9619 ret
= xa_alloc_cyclic(&ctx
->personalities
, &id
, (void *)creds
,
9620 XA_LIMIT(0, USHRT_MAX
), &ctx
->pers_next
, GFP_KERNEL
);
9627 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9628 unsigned int nr_args
)
9630 struct io_uring_restriction
*res
;
9634 /* Restrictions allowed only if rings started disabled */
9635 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9638 /* We allow only a single restrictions registration */
9639 if (ctx
->restrictions
.registered
)
9642 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9645 size
= array_size(nr_args
, sizeof(*res
));
9646 if (size
== SIZE_MAX
)
9649 res
= memdup_user(arg
, size
);
9651 return PTR_ERR(res
);
9655 for (i
= 0; i
< nr_args
; i
++) {
9656 switch (res
[i
].opcode
) {
9657 case IORING_RESTRICTION_REGISTER_OP
:
9658 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9663 __set_bit(res
[i
].register_op
,
9664 ctx
->restrictions
.register_op
);
9666 case IORING_RESTRICTION_SQE_OP
:
9667 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9672 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9674 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9675 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9677 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9678 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9687 /* Reset all restrictions if an error happened */
9689 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9691 ctx
->restrictions
.registered
= true;
9697 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9699 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9702 if (ctx
->restrictions
.registered
)
9703 ctx
->restricted
= 1;
9705 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9706 if (ctx
->sq_data
&& wq_has_sleeper(&ctx
->sq_data
->wait
))
9707 wake_up(&ctx
->sq_data
->wait
);
9711 static bool io_register_op_must_quiesce(int op
)
9714 case IORING_REGISTER_FILES
:
9715 case IORING_UNREGISTER_FILES
:
9716 case IORING_REGISTER_FILES_UPDATE
:
9717 case IORING_REGISTER_PROBE
:
9718 case IORING_REGISTER_PERSONALITY
:
9719 case IORING_UNREGISTER_PERSONALITY
:
9726 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
9727 void __user
*arg
, unsigned nr_args
)
9728 __releases(ctx
->uring_lock
)
9729 __acquires(ctx
->uring_lock
)
9734 * We're inside the ring mutex, if the ref is already dying, then
9735 * someone else killed the ctx or is already going through
9736 * io_uring_register().
9738 if (percpu_ref_is_dying(&ctx
->refs
))
9741 if (io_register_op_must_quiesce(opcode
)) {
9742 percpu_ref_kill(&ctx
->refs
);
9745 * Drop uring mutex before waiting for references to exit. If
9746 * another thread is currently inside io_uring_enter() it might
9747 * need to grab the uring_lock to make progress. If we hold it
9748 * here across the drain wait, then we can deadlock. It's safe
9749 * to drop the mutex here, since no new references will come in
9750 * after we've killed the percpu ref.
9752 mutex_unlock(&ctx
->uring_lock
);
9754 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
9757 ret
= io_run_task_work_sig();
9761 mutex_lock(&ctx
->uring_lock
);
9764 io_refs_resurrect(&ctx
->refs
, &ctx
->ref_comp
);
9769 if (ctx
->restricted
) {
9770 if (opcode
>= IORING_REGISTER_LAST
) {
9775 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
9782 case IORING_REGISTER_BUFFERS
:
9783 ret
= io_sqe_buffers_register(ctx
, arg
, nr_args
);
9785 case IORING_UNREGISTER_BUFFERS
:
9789 ret
= io_sqe_buffers_unregister(ctx
);
9791 case IORING_REGISTER_FILES
:
9792 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
9794 case IORING_UNREGISTER_FILES
:
9798 ret
= io_sqe_files_unregister(ctx
);
9800 case IORING_REGISTER_FILES_UPDATE
:
9801 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
9803 case IORING_REGISTER_EVENTFD
:
9804 case IORING_REGISTER_EVENTFD_ASYNC
:
9808 ret
= io_eventfd_register(ctx
, arg
);
9811 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
9812 ctx
->eventfd_async
= 1;
9814 ctx
->eventfd_async
= 0;
9816 case IORING_UNREGISTER_EVENTFD
:
9820 ret
= io_eventfd_unregister(ctx
);
9822 case IORING_REGISTER_PROBE
:
9824 if (!arg
|| nr_args
> 256)
9826 ret
= io_probe(ctx
, arg
, nr_args
);
9828 case IORING_REGISTER_PERSONALITY
:
9832 ret
= io_register_personality(ctx
);
9834 case IORING_UNREGISTER_PERSONALITY
:
9838 ret
= io_unregister_personality(ctx
, nr_args
);
9840 case IORING_REGISTER_ENABLE_RINGS
:
9844 ret
= io_register_enable_rings(ctx
);
9846 case IORING_REGISTER_RESTRICTIONS
:
9847 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
9855 if (io_register_op_must_quiesce(opcode
)) {
9856 /* bring the ctx back to life */
9857 percpu_ref_reinit(&ctx
->refs
);
9858 reinit_completion(&ctx
->ref_comp
);
9863 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
9864 void __user
*, arg
, unsigned int, nr_args
)
9866 struct io_ring_ctx
*ctx
;
9875 if (f
.file
->f_op
!= &io_uring_fops
)
9878 ctx
= f
.file
->private_data
;
9882 mutex_lock(&ctx
->uring_lock
);
9883 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
9884 mutex_unlock(&ctx
->uring_lock
);
9885 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
9886 ctx
->cq_ev_fd
!= NULL
, ret
);
9892 static int __init
io_uring_init(void)
9894 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
9895 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
9896 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
9899 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
9900 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
9901 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
9902 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
9903 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
9904 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
9905 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
9906 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
9907 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
9908 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
9909 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
9910 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
9911 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
9912 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
9913 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
9914 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
9915 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
9916 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
9917 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
9918 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
9919 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
9920 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
9921 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
9922 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
9923 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
9924 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
9925 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
9926 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
9927 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
9928 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
9929 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
9931 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
9932 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
9933 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
|
9937 __initcall(io_uring_init
);