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_cqe (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)
92 #define IORING_SQPOLL_CAP_ENTRIES_VALUE 8
95 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
97 #define IORING_FILE_TABLE_SHIFT 9
98 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
99 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
100 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
101 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
102 IORING_REGISTER_LAST + IORING_OP_LAST)
104 #define IO_RSRC_TAG_TABLE_SHIFT 9
105 #define IO_RSRC_TAG_TABLE_MAX (1U << IO_RSRC_TAG_TABLE_SHIFT)
106 #define IO_RSRC_TAG_TABLE_MASK (IO_RSRC_TAG_TABLE_MAX - 1)
108 #define IORING_MAX_REG_BUFFERS (1U << 14)
110 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
111 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
113 #define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
114 REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS)
116 #define IO_TCTX_REFS_CACHE_NR (1U << 10)
119 u32 head ____cacheline_aligned_in_smp
;
120 u32 tail ____cacheline_aligned_in_smp
;
124 * This data is shared with the application through the mmap at offsets
125 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
127 * The offsets to the member fields are published through struct
128 * io_sqring_offsets when calling io_uring_setup.
132 * Head and tail offsets into the ring; the offsets need to be
133 * masked to get valid indices.
135 * The kernel controls head of the sq ring and the tail of the cq ring,
136 * and the application controls tail of the sq ring and the head of the
139 struct io_uring sq
, cq
;
141 * Bitmasks to apply to head and tail offsets (constant, equals
144 u32 sq_ring_mask
, cq_ring_mask
;
145 /* Ring sizes (constant, power of 2) */
146 u32 sq_ring_entries
, cq_ring_entries
;
148 * Number of invalid entries dropped by the kernel due to
149 * invalid index stored in array
151 * Written by the kernel, shouldn't be modified by the
152 * application (i.e. get number of "new events" by comparing to
155 * After a new SQ head value was read by the application this
156 * counter includes all submissions that were dropped reaching
157 * the new SQ head (and possibly more).
163 * Written by the kernel, shouldn't be modified by the
166 * The application needs a full memory barrier before checking
167 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
173 * Written by the application, shouldn't be modified by the
178 * Number of completion events lost because the queue was full;
179 * this should be avoided by the application by making sure
180 * there are not more requests pending than there is space in
181 * the completion queue.
183 * Written by the kernel, shouldn't be modified by the
184 * application (i.e. get number of "new events" by comparing to
187 * As completion events come in out of order this counter is not
188 * ordered with any other data.
192 * Ring buffer of completion events.
194 * The kernel writes completion events fresh every time they are
195 * produced, so the application is allowed to modify pending
198 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
201 enum io_uring_cmd_flags
{
202 IO_URING_F_NONBLOCK
= 1,
203 IO_URING_F_COMPLETE_DEFER
= 2,
206 struct io_mapped_ubuf
{
209 unsigned int nr_bvecs
;
210 unsigned long acct_pages
;
211 struct bio_vec bvec
[];
216 struct io_overflow_cqe
{
217 struct io_uring_cqe cqe
;
218 struct list_head list
;
221 struct io_fixed_file
{
222 /* file * with additional FFS_* flags */
223 unsigned long file_ptr
;
227 struct list_head list
;
232 struct io_mapped_ubuf
*buf
;
236 struct io_file_table
{
237 /* two level table */
238 struct io_fixed_file
**files
;
241 struct io_rsrc_node
{
242 struct percpu_ref refs
;
243 struct list_head node
;
244 struct list_head rsrc_list
;
245 struct io_rsrc_data
*rsrc_data
;
246 struct llist_node llist
;
250 typedef void (rsrc_put_fn
)(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
);
252 struct io_rsrc_data
{
253 struct io_ring_ctx
*ctx
;
259 struct completion done
;
264 struct list_head list
;
270 struct io_restriction
{
271 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
272 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
273 u8 sqe_flags_allowed
;
274 u8 sqe_flags_required
;
279 IO_SQ_THREAD_SHOULD_STOP
= 0,
280 IO_SQ_THREAD_SHOULD_PARK
,
285 atomic_t park_pending
;
288 /* ctx's that are using this sqd */
289 struct list_head ctx_list
;
291 struct task_struct
*thread
;
292 struct wait_queue_head wait
;
294 unsigned sq_thread_idle
;
300 struct completion exited
;
303 #define IO_IOPOLL_BATCH 8
304 #define IO_COMPL_BATCH 32
305 #define IO_REQ_CACHE_SIZE 32
306 #define IO_REQ_ALLOC_BATCH 8
308 struct io_comp_state
{
309 struct io_kiocb
*reqs
[IO_COMPL_BATCH
];
311 /* inline/task_work completion list, under ->uring_lock */
312 struct list_head free_list
;
315 struct io_submit_link
{
316 struct io_kiocb
*head
;
317 struct io_kiocb
*last
;
320 struct io_submit_state
{
321 struct blk_plug plug
;
322 struct io_submit_link link
;
325 * io_kiocb alloc cache
327 void *reqs
[IO_REQ_CACHE_SIZE
];
328 unsigned int free_reqs
;
333 * Batch completion logic
335 struct io_comp_state comp
;
338 * File reference cache
342 unsigned int file_refs
;
343 unsigned int ios_left
;
347 /* const or read-mostly hot data */
349 struct percpu_ref refs
;
351 struct io_rings
*rings
;
353 unsigned int compat
: 1;
354 unsigned int drain_next
: 1;
355 unsigned int eventfd_async
: 1;
356 unsigned int restricted
: 1;
357 unsigned int off_timeout_used
: 1;
358 unsigned int drain_active
: 1;
359 } ____cacheline_aligned_in_smp
;
361 /* submission data */
363 struct mutex uring_lock
;
366 * Ring buffer of indices into array of io_uring_sqe, which is
367 * mmapped by the application using the IORING_OFF_SQES offset.
369 * This indirection could e.g. be used to assign fixed
370 * io_uring_sqe entries to operations and only submit them to
371 * the queue when needed.
373 * The kernel modifies neither the indices array nor the entries
377 struct io_uring_sqe
*sq_sqes
;
378 unsigned cached_sq_head
;
380 struct list_head defer_list
;
383 * Fixed resources fast path, should be accessed only under
384 * uring_lock, and updated through io_uring_register(2)
386 struct io_rsrc_node
*rsrc_node
;
387 struct io_file_table file_table
;
388 unsigned nr_user_files
;
389 unsigned nr_user_bufs
;
390 struct io_mapped_ubuf
**user_bufs
;
392 struct io_submit_state submit_state
;
393 struct list_head timeout_list
;
394 struct list_head cq_overflow_list
;
395 struct xarray io_buffers
;
396 struct xarray personalities
;
398 unsigned sq_thread_idle
;
399 } ____cacheline_aligned_in_smp
;
401 /* IRQ completion list, under ->completion_lock */
402 struct list_head locked_free_list
;
403 unsigned int locked_free_nr
;
405 const struct cred
*sq_creds
; /* cred used for __io_sq_thread() */
406 struct io_sq_data
*sq_data
; /* if using sq thread polling */
408 struct wait_queue_head sqo_sq_wait
;
409 struct list_head sqd_list
;
411 unsigned long check_cq_overflow
;
414 unsigned cached_cq_tail
;
416 struct eventfd_ctx
*cq_ev_fd
;
417 struct wait_queue_head poll_wait
;
418 struct wait_queue_head cq_wait
;
420 atomic_t cq_timeouts
;
421 struct fasync_struct
*cq_fasync
;
422 unsigned cq_last_tm_flush
;
423 } ____cacheline_aligned_in_smp
;
426 spinlock_t completion_lock
;
429 * ->iopoll_list is protected by the ctx->uring_lock for
430 * io_uring instances that don't use IORING_SETUP_SQPOLL.
431 * For SQPOLL, only the single threaded io_sq_thread() will
432 * manipulate the list, hence no extra locking is needed there.
434 struct list_head iopoll_list
;
435 struct hlist_head
*cancel_hash
;
436 unsigned cancel_hash_bits
;
437 bool poll_multi_queue
;
438 } ____cacheline_aligned_in_smp
;
440 struct io_restriction restrictions
;
442 /* slow path rsrc auxilary data, used by update/register */
444 struct io_rsrc_node
*rsrc_backup_node
;
445 struct io_mapped_ubuf
*dummy_ubuf
;
446 struct io_rsrc_data
*file_data
;
447 struct io_rsrc_data
*buf_data
;
449 struct delayed_work rsrc_put_work
;
450 struct llist_head rsrc_put_llist
;
451 struct list_head rsrc_ref_list
;
452 spinlock_t rsrc_ref_lock
;
455 /* Keep this last, we don't need it for the fast path */
457 #if defined(CONFIG_UNIX)
458 struct socket
*ring_sock
;
460 /* hashed buffered write serialization */
461 struct io_wq_hash
*hash_map
;
463 /* Only used for accounting purposes */
464 struct user_struct
*user
;
465 struct mm_struct
*mm_account
;
467 /* ctx exit and cancelation */
468 struct llist_head fallback_llist
;
469 struct delayed_work fallback_work
;
470 struct work_struct exit_work
;
471 struct list_head tctx_list
;
472 struct completion ref_comp
;
476 struct io_uring_task
{
477 /* submission side */
480 struct wait_queue_head wait
;
481 const struct io_ring_ctx
*last
;
483 struct percpu_counter inflight
;
484 atomic_t inflight_tracked
;
487 spinlock_t task_lock
;
488 struct io_wq_work_list task_list
;
489 unsigned long task_state
;
490 struct callback_head task_work
;
494 * First field must be the file pointer in all the
495 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
497 struct io_poll_iocb
{
499 struct wait_queue_head
*head
;
503 struct wait_queue_entry wait
;
506 struct io_poll_update
{
512 bool update_user_data
;
520 struct io_timeout_data
{
521 struct io_kiocb
*req
;
522 struct hrtimer timer
;
523 struct timespec64 ts
;
524 enum hrtimer_mode mode
;
529 struct sockaddr __user
*addr
;
530 int __user
*addr_len
;
532 unsigned long nofile
;
552 struct list_head list
;
553 /* head of the link, used by linked timeouts only */
554 struct io_kiocb
*head
;
557 struct io_timeout_rem
{
562 struct timespec64 ts
;
567 /* NOTE: kiocb has the file as the first member, so don't do it here */
575 struct sockaddr __user
*addr
;
582 struct compat_msghdr __user
*umsg_compat
;
583 struct user_msghdr __user
*umsg
;
589 struct io_buffer
*kbuf
;
595 struct filename
*filename
;
597 unsigned long nofile
;
600 struct io_rsrc_update
{
626 struct epoll_event event
;
630 struct file
*file_out
;
631 struct file
*file_in
;
638 struct io_provide_buf
{
652 const char __user
*filename
;
653 struct statx __user
*buffer
;
665 struct filename
*oldpath
;
666 struct filename
*newpath
;
674 struct filename
*filename
;
677 struct io_completion
{
679 struct list_head list
;
683 struct io_async_connect
{
684 struct sockaddr_storage address
;
687 struct io_async_msghdr
{
688 struct iovec fast_iov
[UIO_FASTIOV
];
689 /* points to an allocated iov, if NULL we use fast_iov instead */
690 struct iovec
*free_iov
;
691 struct sockaddr __user
*uaddr
;
693 struct sockaddr_storage addr
;
697 struct iovec fast_iov
[UIO_FASTIOV
];
698 const struct iovec
*free_iovec
;
699 struct iov_iter iter
;
701 struct wait_page_queue wpq
;
705 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
706 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
707 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
708 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
709 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
710 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
712 /* first byte is taken by user flags, shift it to not overlap */
717 REQ_F_LINK_TIMEOUT_BIT
,
718 REQ_F_NEED_CLEANUP_BIT
,
720 REQ_F_BUFFER_SELECTED_BIT
,
721 REQ_F_LTIMEOUT_ACTIVE_BIT
,
722 REQ_F_COMPLETE_INLINE_BIT
,
724 REQ_F_DONT_REISSUE_BIT
,
726 /* keep async read/write and isreg together and in order */
727 REQ_F_ASYNC_READ_BIT
,
728 REQ_F_ASYNC_WRITE_BIT
,
731 /* not a real bit, just to check we're not overflowing the space */
737 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
738 /* drain existing IO first */
739 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
741 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
742 /* doesn't sever on completion < 0 */
743 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
745 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
746 /* IOSQE_BUFFER_SELECT */
747 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
749 /* fail rest of links */
750 REQ_F_FAIL
= BIT(REQ_F_FAIL_BIT
),
751 /* on inflight list, should be cancelled and waited on exit reliably */
752 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
753 /* read/write uses file position */
754 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
755 /* must not punt to workers */
756 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
757 /* has or had linked timeout */
758 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
760 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
761 /* already went through poll handler */
762 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
763 /* buffer already selected */
764 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
765 /* linked timeout is active, i.e. prepared by link's head */
766 REQ_F_LTIMEOUT_ACTIVE
= BIT(REQ_F_LTIMEOUT_ACTIVE_BIT
),
767 /* completion is deferred through io_comp_state */
768 REQ_F_COMPLETE_INLINE
= BIT(REQ_F_COMPLETE_INLINE_BIT
),
769 /* caller should reissue async */
770 REQ_F_REISSUE
= BIT(REQ_F_REISSUE_BIT
),
771 /* don't attempt request reissue, see io_rw_reissue() */
772 REQ_F_DONT_REISSUE
= BIT(REQ_F_DONT_REISSUE_BIT
),
773 /* supports async reads */
774 REQ_F_ASYNC_READ
= BIT(REQ_F_ASYNC_READ_BIT
),
775 /* supports async writes */
776 REQ_F_ASYNC_WRITE
= BIT(REQ_F_ASYNC_WRITE_BIT
),
778 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
779 /* has creds assigned */
780 REQ_F_CREDS
= BIT(REQ_F_CREDS_BIT
),
784 struct io_poll_iocb poll
;
785 struct io_poll_iocb
*double_poll
;
788 typedef void (*io_req_tw_func_t
)(struct io_kiocb
*req
);
790 struct io_task_work
{
792 struct io_wq_work_node node
;
793 struct llist_node fallback_node
;
795 io_req_tw_func_t func
;
799 IORING_RSRC_FILE
= 0,
800 IORING_RSRC_BUFFER
= 1,
804 * NOTE! Each of the iocb union members has the file pointer
805 * as the first entry in their struct definition. So you can
806 * access the file pointer through any of the sub-structs,
807 * or directly as just 'ki_filp' in this struct.
813 struct io_poll_iocb poll
;
814 struct io_poll_update poll_update
;
815 struct io_accept accept
;
817 struct io_cancel cancel
;
818 struct io_timeout timeout
;
819 struct io_timeout_rem timeout_rem
;
820 struct io_connect connect
;
821 struct io_sr_msg sr_msg
;
823 struct io_close close
;
824 struct io_rsrc_update rsrc_update
;
825 struct io_fadvise fadvise
;
826 struct io_madvise madvise
;
827 struct io_epoll epoll
;
828 struct io_splice splice
;
829 struct io_provide_buf pbuf
;
830 struct io_statx statx
;
831 struct io_shutdown shutdown
;
832 struct io_rename rename
;
833 struct io_unlink unlink
;
834 /* use only after cleaning per-op data, see io_clean_op() */
835 struct io_completion
compl;
838 /* opcode allocated if it needs to store data for async defer */
841 /* polled IO has completed */
847 struct io_ring_ctx
*ctx
;
850 struct task_struct
*task
;
853 struct io_kiocb
*link
;
854 struct percpu_ref
*fixed_rsrc_refs
;
856 /* used with ctx->iopoll_list with reads/writes */
857 struct list_head inflight_entry
;
858 struct io_task_work io_task_work
;
859 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
860 struct hlist_node hash_node
;
861 struct async_poll
*apoll
;
862 struct io_wq_work work
;
863 const struct cred
*creds
;
865 /* store used ubuf, so we can prevent reloading */
866 struct io_mapped_ubuf
*imu
;
869 struct io_tctx_node
{
870 struct list_head ctx_node
;
871 struct task_struct
*task
;
872 struct io_ring_ctx
*ctx
;
875 struct io_defer_entry
{
876 struct list_head list
;
877 struct io_kiocb
*req
;
882 /* needs req->file assigned */
883 unsigned needs_file
: 1;
884 /* hash wq insertion if file is a regular file */
885 unsigned hash_reg_file
: 1;
886 /* unbound wq insertion if file is a non-regular file */
887 unsigned unbound_nonreg_file
: 1;
888 /* opcode is not supported by this kernel */
889 unsigned not_supported
: 1;
890 /* set if opcode supports polled "wait" */
892 unsigned pollout
: 1;
893 /* op supports buffer selection */
894 unsigned buffer_select
: 1;
895 /* do prep async if is going to be punted */
896 unsigned needs_async_setup
: 1;
897 /* should block plug */
899 /* size of async data needed, if any */
900 unsigned short async_size
;
903 static const struct io_op_def io_op_defs
[] = {
904 [IORING_OP_NOP
] = {},
905 [IORING_OP_READV
] = {
907 .unbound_nonreg_file
= 1,
910 .needs_async_setup
= 1,
912 .async_size
= sizeof(struct io_async_rw
),
914 [IORING_OP_WRITEV
] = {
917 .unbound_nonreg_file
= 1,
919 .needs_async_setup
= 1,
921 .async_size
= sizeof(struct io_async_rw
),
923 [IORING_OP_FSYNC
] = {
926 [IORING_OP_READ_FIXED
] = {
928 .unbound_nonreg_file
= 1,
931 .async_size
= sizeof(struct io_async_rw
),
933 [IORING_OP_WRITE_FIXED
] = {
936 .unbound_nonreg_file
= 1,
939 .async_size
= sizeof(struct io_async_rw
),
941 [IORING_OP_POLL_ADD
] = {
943 .unbound_nonreg_file
= 1,
945 [IORING_OP_POLL_REMOVE
] = {},
946 [IORING_OP_SYNC_FILE_RANGE
] = {
949 [IORING_OP_SENDMSG
] = {
951 .unbound_nonreg_file
= 1,
953 .needs_async_setup
= 1,
954 .async_size
= sizeof(struct io_async_msghdr
),
956 [IORING_OP_RECVMSG
] = {
958 .unbound_nonreg_file
= 1,
961 .needs_async_setup
= 1,
962 .async_size
= sizeof(struct io_async_msghdr
),
964 [IORING_OP_TIMEOUT
] = {
965 .async_size
= sizeof(struct io_timeout_data
),
967 [IORING_OP_TIMEOUT_REMOVE
] = {
968 /* used by timeout updates' prep() */
970 [IORING_OP_ACCEPT
] = {
972 .unbound_nonreg_file
= 1,
975 [IORING_OP_ASYNC_CANCEL
] = {},
976 [IORING_OP_LINK_TIMEOUT
] = {
977 .async_size
= sizeof(struct io_timeout_data
),
979 [IORING_OP_CONNECT
] = {
981 .unbound_nonreg_file
= 1,
983 .needs_async_setup
= 1,
984 .async_size
= sizeof(struct io_async_connect
),
986 [IORING_OP_FALLOCATE
] = {
989 [IORING_OP_OPENAT
] = {},
990 [IORING_OP_CLOSE
] = {},
991 [IORING_OP_FILES_UPDATE
] = {},
992 [IORING_OP_STATX
] = {},
995 .unbound_nonreg_file
= 1,
999 .async_size
= sizeof(struct io_async_rw
),
1001 [IORING_OP_WRITE
] = {
1003 .unbound_nonreg_file
= 1,
1006 .async_size
= sizeof(struct io_async_rw
),
1008 [IORING_OP_FADVISE
] = {
1011 [IORING_OP_MADVISE
] = {},
1012 [IORING_OP_SEND
] = {
1014 .unbound_nonreg_file
= 1,
1017 [IORING_OP_RECV
] = {
1019 .unbound_nonreg_file
= 1,
1023 [IORING_OP_OPENAT2
] = {
1025 [IORING_OP_EPOLL_CTL
] = {
1026 .unbound_nonreg_file
= 1,
1028 [IORING_OP_SPLICE
] = {
1031 .unbound_nonreg_file
= 1,
1033 [IORING_OP_PROVIDE_BUFFERS
] = {},
1034 [IORING_OP_REMOVE_BUFFERS
] = {},
1038 .unbound_nonreg_file
= 1,
1040 [IORING_OP_SHUTDOWN
] = {
1043 [IORING_OP_RENAMEAT
] = {},
1044 [IORING_OP_UNLINKAT
] = {},
1047 static bool io_disarm_next(struct io_kiocb
*req
);
1048 static void io_uring_del_tctx_node(unsigned long index
);
1049 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
1050 struct task_struct
*task
,
1052 static void io_uring_cancel_generic(bool cancel_all
, struct io_sq_data
*sqd
);
1053 static struct io_rsrc_node
*io_rsrc_node_alloc(struct io_ring_ctx
*ctx
);
1055 static bool io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1056 long res
, unsigned int cflags
);
1057 static void io_put_req(struct io_kiocb
*req
);
1058 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
1059 static void io_dismantle_req(struct io_kiocb
*req
);
1060 static void io_put_task(struct task_struct
*task
, int nr
);
1061 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
1062 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1063 static int __io_register_rsrc_update(struct io_ring_ctx
*ctx
, unsigned type
,
1064 struct io_uring_rsrc_update2
*up
,
1066 static void io_clean_op(struct io_kiocb
*req
);
1067 static struct file
*io_file_get(struct io_submit_state
*state
,
1068 struct io_kiocb
*req
, int fd
, bool fixed
);
1069 static void __io_queue_sqe(struct io_kiocb
*req
);
1070 static void io_rsrc_put_work(struct work_struct
*work
);
1072 static void io_req_task_queue(struct io_kiocb
*req
);
1073 static void io_submit_flush_completions(struct io_ring_ctx
*ctx
);
1074 static bool io_poll_remove_waitqs(struct io_kiocb
*req
);
1075 static int io_req_prep_async(struct io_kiocb
*req
);
1077 static void io_fallback_req_func(struct work_struct
*unused
);
1079 static struct kmem_cache
*req_cachep
;
1081 static const struct file_operations io_uring_fops
;
1083 struct sock
*io_uring_get_socket(struct file
*file
)
1085 #if defined(CONFIG_UNIX)
1086 if (file
->f_op
== &io_uring_fops
) {
1087 struct io_ring_ctx
*ctx
= file
->private_data
;
1089 return ctx
->ring_sock
->sk
;
1094 EXPORT_SYMBOL(io_uring_get_socket
);
1096 #define io_for_each_link(pos, head) \
1097 for (pos = (head); pos; pos = pos->link)
1099 static inline void io_req_set_rsrc_node(struct io_kiocb
*req
)
1101 struct io_ring_ctx
*ctx
= req
->ctx
;
1103 if (!req
->fixed_rsrc_refs
) {
1104 req
->fixed_rsrc_refs
= &ctx
->rsrc_node
->refs
;
1105 percpu_ref_get(req
->fixed_rsrc_refs
);
1109 static void io_refs_resurrect(struct percpu_ref
*ref
, struct completion
*compl)
1111 bool got
= percpu_ref_tryget(ref
);
1113 /* already at zero, wait for ->release() */
1115 wait_for_completion(compl);
1116 percpu_ref_resurrect(ref
);
1118 percpu_ref_put(ref
);
1121 static bool io_match_task(struct io_kiocb
*head
, struct task_struct
*task
,
1124 struct io_kiocb
*req
;
1126 if (task
&& head
->task
!= task
)
1131 io_for_each_link(req
, head
) {
1132 if (req
->flags
& REQ_F_INFLIGHT
)
1138 static inline void req_set_fail(struct io_kiocb
*req
)
1140 req
->flags
|= REQ_F_FAIL
;
1143 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1145 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1147 complete(&ctx
->ref_comp
);
1150 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1152 return !req
->timeout
.off
;
1155 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1157 struct io_ring_ctx
*ctx
;
1160 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1165 * Use 5 bits less than the max cq entries, that should give us around
1166 * 32 entries per hash list if totally full and uniformly spread.
1168 hash_bits
= ilog2(p
->cq_entries
);
1172 ctx
->cancel_hash_bits
= hash_bits
;
1173 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1175 if (!ctx
->cancel_hash
)
1177 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1179 ctx
->dummy_ubuf
= kzalloc(sizeof(*ctx
->dummy_ubuf
), GFP_KERNEL
);
1180 if (!ctx
->dummy_ubuf
)
1182 /* set invalid range, so io_import_fixed() fails meeting it */
1183 ctx
->dummy_ubuf
->ubuf
= -1UL;
1185 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1186 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1189 ctx
->flags
= p
->flags
;
1190 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1191 INIT_LIST_HEAD(&ctx
->sqd_list
);
1192 init_waitqueue_head(&ctx
->poll_wait
);
1193 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1194 init_completion(&ctx
->ref_comp
);
1195 xa_init_flags(&ctx
->io_buffers
, XA_FLAGS_ALLOC1
);
1196 xa_init_flags(&ctx
->personalities
, XA_FLAGS_ALLOC1
);
1197 mutex_init(&ctx
->uring_lock
);
1198 init_waitqueue_head(&ctx
->cq_wait
);
1199 spin_lock_init(&ctx
->completion_lock
);
1200 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1201 INIT_LIST_HEAD(&ctx
->defer_list
);
1202 INIT_LIST_HEAD(&ctx
->timeout_list
);
1203 spin_lock_init(&ctx
->rsrc_ref_lock
);
1204 INIT_LIST_HEAD(&ctx
->rsrc_ref_list
);
1205 INIT_DELAYED_WORK(&ctx
->rsrc_put_work
, io_rsrc_put_work
);
1206 init_llist_head(&ctx
->rsrc_put_llist
);
1207 INIT_LIST_HEAD(&ctx
->tctx_list
);
1208 INIT_LIST_HEAD(&ctx
->submit_state
.comp
.free_list
);
1209 INIT_LIST_HEAD(&ctx
->locked_free_list
);
1210 INIT_DELAYED_WORK(&ctx
->fallback_work
, io_fallback_req_func
);
1213 kfree(ctx
->dummy_ubuf
);
1214 kfree(ctx
->cancel_hash
);
1219 static void io_account_cq_overflow(struct io_ring_ctx
*ctx
)
1221 struct io_rings
*r
= ctx
->rings
;
1223 WRITE_ONCE(r
->cq_overflow
, READ_ONCE(r
->cq_overflow
) + 1);
1227 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1229 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1230 struct io_ring_ctx
*ctx
= req
->ctx
;
1232 return seq
+ READ_ONCE(ctx
->cq_extra
) != ctx
->cached_cq_tail
;
1238 static void io_req_track_inflight(struct io_kiocb
*req
)
1240 if (!(req
->flags
& REQ_F_INFLIGHT
)) {
1241 req
->flags
|= REQ_F_INFLIGHT
;
1242 atomic_inc(¤t
->io_uring
->inflight_tracked
);
1246 static void io_prep_async_work(struct io_kiocb
*req
)
1248 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1249 struct io_ring_ctx
*ctx
= req
->ctx
;
1251 if (!(req
->flags
& REQ_F_CREDS
)) {
1252 req
->flags
|= REQ_F_CREDS
;
1253 req
->creds
= get_current_cred();
1256 req
->work
.list
.next
= NULL
;
1257 req
->work
.flags
= 0;
1258 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1259 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1261 if (req
->flags
& REQ_F_ISREG
) {
1262 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1263 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1264 } else if (!req
->file
|| !S_ISBLK(file_inode(req
->file
)->i_mode
)) {
1265 if (def
->unbound_nonreg_file
)
1266 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1269 switch (req
->opcode
) {
1270 case IORING_OP_SPLICE
:
1272 if (!S_ISREG(file_inode(req
->splice
.file_in
)->i_mode
))
1273 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1278 static void io_prep_async_link(struct io_kiocb
*req
)
1280 struct io_kiocb
*cur
;
1282 if (req
->flags
& REQ_F_LINK_TIMEOUT
) {
1283 struct io_ring_ctx
*ctx
= req
->ctx
;
1285 spin_lock_irq(&ctx
->completion_lock
);
1286 io_for_each_link(cur
, req
)
1287 io_prep_async_work(cur
);
1288 spin_unlock_irq(&ctx
->completion_lock
);
1290 io_for_each_link(cur
, req
)
1291 io_prep_async_work(cur
);
1295 static void io_queue_async_work(struct io_kiocb
*req
)
1297 struct io_ring_ctx
*ctx
= req
->ctx
;
1298 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1299 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1302 BUG_ON(!tctx
->io_wq
);
1304 /* init ->work of the whole link before punting */
1305 io_prep_async_link(req
);
1308 * Not expected to happen, but if we do have a bug where this _can_
1309 * happen, catch it here and ensure the request is marked as
1310 * canceled. That will make io-wq go through the usual work cancel
1311 * procedure rather than attempt to run this request (or create a new
1314 if (WARN_ON_ONCE(!same_thread_group(req
->task
, current
)))
1315 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1317 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1318 &req
->work
, req
->flags
);
1319 io_wq_enqueue(tctx
->io_wq
, &req
->work
);
1321 io_queue_linked_timeout(link
);
1324 static void io_kill_timeout(struct io_kiocb
*req
, int status
)
1325 __must_hold(&req
->ctx
->completion_lock
)
1327 struct io_timeout_data
*io
= req
->async_data
;
1329 if (hrtimer_try_to_cancel(&io
->timer
) != -1) {
1330 atomic_set(&req
->ctx
->cq_timeouts
,
1331 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1332 list_del_init(&req
->timeout
.list
);
1333 io_cqring_fill_event(req
->ctx
, req
->user_data
, status
, 0);
1334 io_put_req_deferred(req
, 1);
1338 static void io_queue_deferred(struct io_ring_ctx
*ctx
)
1340 while (!list_empty(&ctx
->defer_list
)) {
1341 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1342 struct io_defer_entry
, list
);
1344 if (req_need_defer(de
->req
, de
->seq
))
1346 list_del_init(&de
->list
);
1347 io_req_task_queue(de
->req
);
1352 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1354 u32 seq
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
1356 while (!list_empty(&ctx
->timeout_list
)) {
1357 u32 events_needed
, events_got
;
1358 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1359 struct io_kiocb
, timeout
.list
);
1361 if (io_is_timeout_noseq(req
))
1365 * Since seq can easily wrap around over time, subtract
1366 * the last seq at which timeouts were flushed before comparing.
1367 * Assuming not more than 2^31-1 events have happened since,
1368 * these subtractions won't have wrapped, so we can check if
1369 * target is in [last_seq, current_seq] by comparing the two.
1371 events_needed
= req
->timeout
.target_seq
- ctx
->cq_last_tm_flush
;
1372 events_got
= seq
- ctx
->cq_last_tm_flush
;
1373 if (events_got
< events_needed
)
1376 list_del_init(&req
->timeout
.list
);
1377 io_kill_timeout(req
, 0);
1379 ctx
->cq_last_tm_flush
= seq
;
1382 static void __io_commit_cqring_flush(struct io_ring_ctx
*ctx
)
1384 if (ctx
->off_timeout_used
)
1385 io_flush_timeouts(ctx
);
1386 if (ctx
->drain_active
)
1387 io_queue_deferred(ctx
);
1390 static inline void io_commit_cqring(struct io_ring_ctx
*ctx
)
1392 if (unlikely(ctx
->off_timeout_used
|| ctx
->drain_active
))
1393 __io_commit_cqring_flush(ctx
);
1394 /* order cqe stores with ring update */
1395 smp_store_release(&ctx
->rings
->cq
.tail
, ctx
->cached_cq_tail
);
1398 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1400 struct io_rings
*r
= ctx
->rings
;
1402 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== ctx
->sq_entries
;
1405 static inline unsigned int __io_cqring_events(struct io_ring_ctx
*ctx
)
1407 return ctx
->cached_cq_tail
- READ_ONCE(ctx
->rings
->cq
.head
);
1410 static inline struct io_uring_cqe
*io_get_cqe(struct io_ring_ctx
*ctx
)
1412 struct io_rings
*rings
= ctx
->rings
;
1413 unsigned tail
, mask
= ctx
->cq_entries
- 1;
1416 * writes to the cq entry need to come after reading head; the
1417 * control dependency is enough as we're using WRITE_ONCE to
1420 if (__io_cqring_events(ctx
) == ctx
->cq_entries
)
1423 tail
= ctx
->cached_cq_tail
++;
1424 return &rings
->cqes
[tail
& mask
];
1427 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1429 if (likely(!ctx
->cq_ev_fd
))
1431 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1433 return !ctx
->eventfd_async
|| io_wq_current_is_worker();
1436 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1438 /* see waitqueue_active() comment */
1441 if (waitqueue_active(&ctx
->cq_wait
))
1442 wake_up(&ctx
->cq_wait
);
1443 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1444 wake_up(&ctx
->sq_data
->wait
);
1445 if (io_should_trigger_evfd(ctx
))
1446 eventfd_signal(ctx
->cq_ev_fd
, 1);
1447 if (waitqueue_active(&ctx
->poll_wait
)) {
1448 wake_up_interruptible(&ctx
->poll_wait
);
1449 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1453 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx
*ctx
)
1455 /* see waitqueue_active() comment */
1458 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1459 if (waitqueue_active(&ctx
->cq_wait
))
1460 wake_up(&ctx
->cq_wait
);
1462 if (io_should_trigger_evfd(ctx
))
1463 eventfd_signal(ctx
->cq_ev_fd
, 1);
1464 if (waitqueue_active(&ctx
->poll_wait
)) {
1465 wake_up_interruptible(&ctx
->poll_wait
);
1466 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1470 /* Returns true if there are no backlogged entries after the flush */
1471 static bool __io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1473 unsigned long flags
;
1474 bool all_flushed
, posted
;
1476 if (!force
&& __io_cqring_events(ctx
) == ctx
->cq_entries
)
1480 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1481 while (!list_empty(&ctx
->cq_overflow_list
)) {
1482 struct io_uring_cqe
*cqe
= io_get_cqe(ctx
);
1483 struct io_overflow_cqe
*ocqe
;
1487 ocqe
= list_first_entry(&ctx
->cq_overflow_list
,
1488 struct io_overflow_cqe
, list
);
1490 memcpy(cqe
, &ocqe
->cqe
, sizeof(*cqe
));
1492 io_account_cq_overflow(ctx
);
1495 list_del(&ocqe
->list
);
1499 all_flushed
= list_empty(&ctx
->cq_overflow_list
);
1501 clear_bit(0, &ctx
->check_cq_overflow
);
1502 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1506 io_commit_cqring(ctx
);
1507 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1509 io_cqring_ev_posted(ctx
);
1513 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1517 if (test_bit(0, &ctx
->check_cq_overflow
)) {
1518 /* iopoll syncs against uring_lock, not completion_lock */
1519 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1520 mutex_lock(&ctx
->uring_lock
);
1521 ret
= __io_cqring_overflow_flush(ctx
, force
);
1522 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1523 mutex_unlock(&ctx
->uring_lock
);
1530 * Shamelessly stolen from the mm implementation of page reference checking,
1531 * see commit f958d7b528b1 for details.
1533 #define req_ref_zero_or_close_to_overflow(req) \
1534 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1536 static inline bool req_ref_inc_not_zero(struct io_kiocb
*req
)
1538 return atomic_inc_not_zero(&req
->refs
);
1541 static inline bool req_ref_sub_and_test(struct io_kiocb
*req
, int refs
)
1543 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1544 return atomic_sub_and_test(refs
, &req
->refs
);
1547 static inline bool req_ref_put_and_test(struct io_kiocb
*req
)
1549 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1550 return atomic_dec_and_test(&req
->refs
);
1553 static inline void req_ref_put(struct io_kiocb
*req
)
1555 WARN_ON_ONCE(req_ref_put_and_test(req
));
1558 static inline void req_ref_get(struct io_kiocb
*req
)
1560 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1561 atomic_inc(&req
->refs
);
1564 static bool io_cqring_event_overflow(struct io_ring_ctx
*ctx
, u64 user_data
,
1565 long res
, unsigned int cflags
)
1567 struct io_overflow_cqe
*ocqe
;
1569 ocqe
= kmalloc(sizeof(*ocqe
), GFP_ATOMIC
| __GFP_ACCOUNT
);
1572 * If we're in ring overflow flush mode, or in task cancel mode,
1573 * or cannot allocate an overflow entry, then we need to drop it
1576 io_account_cq_overflow(ctx
);
1579 if (list_empty(&ctx
->cq_overflow_list
)) {
1580 set_bit(0, &ctx
->check_cq_overflow
);
1581 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1583 ocqe
->cqe
.user_data
= user_data
;
1584 ocqe
->cqe
.res
= res
;
1585 ocqe
->cqe
.flags
= cflags
;
1586 list_add_tail(&ocqe
->list
, &ctx
->cq_overflow_list
);
1590 static inline bool __io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1591 long res
, unsigned int cflags
)
1593 struct io_uring_cqe
*cqe
;
1595 trace_io_uring_complete(ctx
, user_data
, res
, cflags
);
1598 * If we can't get a cq entry, userspace overflowed the
1599 * submission (by quite a lot). Increment the overflow count in
1602 cqe
= io_get_cqe(ctx
);
1604 WRITE_ONCE(cqe
->user_data
, user_data
);
1605 WRITE_ONCE(cqe
->res
, res
);
1606 WRITE_ONCE(cqe
->flags
, cflags
);
1609 return io_cqring_event_overflow(ctx
, user_data
, res
, cflags
);
1612 /* not as hot to bloat with inlining */
1613 static noinline
bool io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1614 long res
, unsigned int cflags
)
1616 return __io_cqring_fill_event(ctx
, user_data
, res
, cflags
);
1619 static void io_req_complete_post(struct io_kiocb
*req
, long res
,
1620 unsigned int cflags
)
1622 struct io_ring_ctx
*ctx
= req
->ctx
;
1623 unsigned long flags
;
1625 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1626 __io_cqring_fill_event(ctx
, req
->user_data
, res
, cflags
);
1628 * If we're the last reference to this request, add to our locked
1631 if (req_ref_put_and_test(req
)) {
1632 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
1633 if (req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_FAIL
))
1634 io_disarm_next(req
);
1636 io_req_task_queue(req
->link
);
1640 io_dismantle_req(req
);
1641 io_put_task(req
->task
, 1);
1642 list_add(&req
->compl.list
, &ctx
->locked_free_list
);
1643 ctx
->locked_free_nr
++;
1645 if (!percpu_ref_tryget(&ctx
->refs
))
1648 io_commit_cqring(ctx
);
1649 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1652 io_cqring_ev_posted(ctx
);
1653 percpu_ref_put(&ctx
->refs
);
1657 static inline bool io_req_needs_clean(struct io_kiocb
*req
)
1659 return req
->flags
& IO_REQ_CLEAN_FLAGS
;
1662 static void io_req_complete_state(struct io_kiocb
*req
, long res
,
1663 unsigned int cflags
)
1665 if (io_req_needs_clean(req
))
1668 req
->compl.cflags
= cflags
;
1669 req
->flags
|= REQ_F_COMPLETE_INLINE
;
1672 static inline void __io_req_complete(struct io_kiocb
*req
, unsigned issue_flags
,
1673 long res
, unsigned cflags
)
1675 if (issue_flags
& IO_URING_F_COMPLETE_DEFER
)
1676 io_req_complete_state(req
, res
, cflags
);
1678 io_req_complete_post(req
, res
, cflags
);
1681 static inline void io_req_complete(struct io_kiocb
*req
, long res
)
1683 __io_req_complete(req
, 0, res
, 0);
1686 static void io_req_complete_failed(struct io_kiocb
*req
, long res
)
1690 io_req_complete_post(req
, res
, 0);
1693 static void io_flush_cached_locked_reqs(struct io_ring_ctx
*ctx
,
1694 struct io_comp_state
*cs
)
1696 spin_lock_irq(&ctx
->completion_lock
);
1697 list_splice_init(&ctx
->locked_free_list
, &cs
->free_list
);
1698 ctx
->locked_free_nr
= 0;
1699 spin_unlock_irq(&ctx
->completion_lock
);
1702 /* Returns true IFF there are requests in the cache */
1703 static bool io_flush_cached_reqs(struct io_ring_ctx
*ctx
)
1705 struct io_submit_state
*state
= &ctx
->submit_state
;
1706 struct io_comp_state
*cs
= &state
->comp
;
1710 * If we have more than a batch's worth of requests in our IRQ side
1711 * locked cache, grab the lock and move them over to our submission
1714 if (READ_ONCE(ctx
->locked_free_nr
) > IO_COMPL_BATCH
)
1715 io_flush_cached_locked_reqs(ctx
, cs
);
1717 nr
= state
->free_reqs
;
1718 while (!list_empty(&cs
->free_list
)) {
1719 struct io_kiocb
*req
= list_first_entry(&cs
->free_list
,
1720 struct io_kiocb
, compl.list
);
1722 list_del(&req
->compl.list
);
1723 state
->reqs
[nr
++] = req
;
1724 if (nr
== ARRAY_SIZE(state
->reqs
))
1728 state
->free_reqs
= nr
;
1732 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
)
1734 struct io_submit_state
*state
= &ctx
->submit_state
;
1736 BUILD_BUG_ON(ARRAY_SIZE(state
->reqs
) < IO_REQ_ALLOC_BATCH
);
1738 if (!state
->free_reqs
) {
1739 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1742 if (io_flush_cached_reqs(ctx
))
1745 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, IO_REQ_ALLOC_BATCH
,
1749 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1750 * retry single alloc to be on the safe side.
1752 if (unlikely(ret
<= 0)) {
1753 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1754 if (!state
->reqs
[0])
1760 * Don't initialise the fields below on every allocation, but
1761 * do that in advance and keep valid on free.
1763 for (i
= 0; i
< ret
; i
++) {
1764 struct io_kiocb
*req
= state
->reqs
[i
];
1768 req
->async_data
= NULL
;
1769 /* not necessary, but safer to zero */
1772 state
->free_reqs
= ret
;
1776 return state
->reqs
[state
->free_reqs
];
1779 static inline void io_put_file(struct file
*file
)
1785 static void io_dismantle_req(struct io_kiocb
*req
)
1787 unsigned int flags
= req
->flags
;
1789 if (io_req_needs_clean(req
))
1791 if (!(flags
& REQ_F_FIXED_FILE
))
1792 io_put_file(req
->file
);
1793 if (req
->fixed_rsrc_refs
)
1794 percpu_ref_put(req
->fixed_rsrc_refs
);
1795 if (req
->async_data
) {
1796 kfree(req
->async_data
);
1797 req
->async_data
= NULL
;
1801 /* must to be called somewhat shortly after putting a request */
1802 static inline void io_put_task(struct task_struct
*task
, int nr
)
1804 struct io_uring_task
*tctx
= task
->io_uring
;
1806 percpu_counter_sub(&tctx
->inflight
, nr
);
1807 if (unlikely(atomic_read(&tctx
->in_idle
)))
1808 wake_up(&tctx
->wait
);
1809 put_task_struct_many(task
, nr
);
1812 static void __io_free_req(struct io_kiocb
*req
)
1814 struct io_ring_ctx
*ctx
= req
->ctx
;
1816 io_dismantle_req(req
);
1817 io_put_task(req
->task
, 1);
1819 kmem_cache_free(req_cachep
, req
);
1820 percpu_ref_put(&ctx
->refs
);
1823 static inline void io_remove_next_linked(struct io_kiocb
*req
)
1825 struct io_kiocb
*nxt
= req
->link
;
1827 req
->link
= nxt
->link
;
1831 static bool io_kill_linked_timeout(struct io_kiocb
*req
)
1832 __must_hold(&req
->ctx
->completion_lock
)
1834 struct io_kiocb
*link
= req
->link
;
1837 * Can happen if a linked timeout fired and link had been like
1838 * req -> link t-out -> link t-out [-> ...]
1840 if (link
&& (link
->flags
& REQ_F_LTIMEOUT_ACTIVE
)) {
1841 struct io_timeout_data
*io
= link
->async_data
;
1843 io_remove_next_linked(req
);
1844 link
->timeout
.head
= NULL
;
1845 if (hrtimer_try_to_cancel(&io
->timer
) != -1) {
1846 io_cqring_fill_event(link
->ctx
, link
->user_data
,
1848 io_put_req_deferred(link
, 1);
1855 static void io_fail_links(struct io_kiocb
*req
)
1856 __must_hold(&req
->ctx
->completion_lock
)
1858 struct io_kiocb
*nxt
, *link
= req
->link
;
1865 trace_io_uring_fail_link(req
, link
);
1866 io_cqring_fill_event(link
->ctx
, link
->user_data
, -ECANCELED
, 0);
1867 io_put_req_deferred(link
, 2);
1872 static bool io_disarm_next(struct io_kiocb
*req
)
1873 __must_hold(&req
->ctx
->completion_lock
)
1875 bool posted
= false;
1877 if (likely(req
->flags
& REQ_F_LINK_TIMEOUT
))
1878 posted
= io_kill_linked_timeout(req
);
1879 if (unlikely((req
->flags
& REQ_F_FAIL
) &&
1880 !(req
->flags
& REQ_F_HARDLINK
))) {
1881 posted
|= (req
->link
!= NULL
);
1887 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
1889 struct io_kiocb
*nxt
;
1892 * If LINK is set, we have dependent requests in this chain. If we
1893 * didn't fail this request, queue the first one up, moving any other
1894 * dependencies to the next request. In case of failure, fail the rest
1897 if (req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_FAIL
)) {
1898 struct io_ring_ctx
*ctx
= req
->ctx
;
1899 unsigned long flags
;
1902 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1903 posted
= io_disarm_next(req
);
1905 io_commit_cqring(req
->ctx
);
1906 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1908 io_cqring_ev_posted(ctx
);
1915 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
1917 if (likely(!(req
->flags
& (REQ_F_LINK
|REQ_F_HARDLINK
))))
1919 return __io_req_find_next(req
);
1922 static void ctx_flush_and_put(struct io_ring_ctx
*ctx
)
1926 if (ctx
->submit_state
.comp
.nr
) {
1927 mutex_lock(&ctx
->uring_lock
);
1928 io_submit_flush_completions(ctx
);
1929 mutex_unlock(&ctx
->uring_lock
);
1931 percpu_ref_put(&ctx
->refs
);
1934 static void tctx_task_work(struct callback_head
*cb
)
1936 struct io_ring_ctx
*ctx
= NULL
;
1937 struct io_uring_task
*tctx
= container_of(cb
, struct io_uring_task
,
1941 struct io_wq_work_node
*node
;
1943 spin_lock_irq(&tctx
->task_lock
);
1944 node
= tctx
->task_list
.first
;
1945 INIT_WQ_LIST(&tctx
->task_list
);
1946 spin_unlock_irq(&tctx
->task_lock
);
1949 struct io_wq_work_node
*next
= node
->next
;
1950 struct io_kiocb
*req
= container_of(node
, struct io_kiocb
,
1953 if (req
->ctx
!= ctx
) {
1954 ctx_flush_and_put(ctx
);
1956 percpu_ref_get(&ctx
->refs
);
1958 req
->io_task_work
.func(req
);
1961 if (wq_list_empty(&tctx
->task_list
)) {
1962 spin_lock_irq(&tctx
->task_lock
);
1963 clear_bit(0, &tctx
->task_state
);
1964 if (wq_list_empty(&tctx
->task_list
)) {
1965 spin_unlock_irq(&tctx
->task_lock
);
1968 spin_unlock_irq(&tctx
->task_lock
);
1969 /* another tctx_task_work() is enqueued, yield */
1970 if (test_and_set_bit(0, &tctx
->task_state
))
1976 ctx_flush_and_put(ctx
);
1979 static void io_req_task_work_add(struct io_kiocb
*req
)
1981 struct task_struct
*tsk
= req
->task
;
1982 struct io_uring_task
*tctx
= tsk
->io_uring
;
1983 enum task_work_notify_mode notify
;
1984 struct io_wq_work_node
*node
;
1985 unsigned long flags
;
1987 WARN_ON_ONCE(!tctx
);
1989 spin_lock_irqsave(&tctx
->task_lock
, flags
);
1990 wq_list_add_tail(&req
->io_task_work
.node
, &tctx
->task_list
);
1991 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
1993 /* task_work already pending, we're done */
1994 if (test_bit(0, &tctx
->task_state
) ||
1995 test_and_set_bit(0, &tctx
->task_state
))
1997 if (unlikely(tsk
->flags
& PF_EXITING
))
2001 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2002 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2003 * processing task_work. There's no reliable way to tell if TWA_RESUME
2006 notify
= (req
->ctx
->flags
& IORING_SETUP_SQPOLL
) ? TWA_NONE
: TWA_SIGNAL
;
2007 if (!task_work_add(tsk
, &tctx
->task_work
, notify
)) {
2008 wake_up_process(tsk
);
2012 clear_bit(0, &tctx
->task_state
);
2013 spin_lock_irqsave(&tctx
->task_lock
, flags
);
2014 node
= tctx
->task_list
.first
;
2015 INIT_WQ_LIST(&tctx
->task_list
);
2016 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
2019 req
= container_of(node
, struct io_kiocb
, io_task_work
.node
);
2021 if (llist_add(&req
->io_task_work
.fallback_node
,
2022 &req
->ctx
->fallback_llist
))
2023 schedule_delayed_work(&req
->ctx
->fallback_work
, 1);
2027 static void io_req_task_cancel(struct io_kiocb
*req
)
2029 struct io_ring_ctx
*ctx
= req
->ctx
;
2031 /* ctx is guaranteed to stay alive while we hold uring_lock */
2032 mutex_lock(&ctx
->uring_lock
);
2033 io_req_complete_failed(req
, req
->result
);
2034 mutex_unlock(&ctx
->uring_lock
);
2037 static void io_req_task_submit(struct io_kiocb
*req
)
2039 struct io_ring_ctx
*ctx
= req
->ctx
;
2041 /* ctx stays valid until unlock, even if we drop all ours ctx->refs */
2042 mutex_lock(&ctx
->uring_lock
);
2043 if (!(req
->task
->flags
& PF_EXITING
) && !req
->task
->in_execve
)
2044 __io_queue_sqe(req
);
2046 io_req_complete_failed(req
, -EFAULT
);
2047 mutex_unlock(&ctx
->uring_lock
);
2050 static void io_req_task_queue_fail(struct io_kiocb
*req
, int ret
)
2053 req
->io_task_work
.func
= io_req_task_cancel
;
2054 io_req_task_work_add(req
);
2057 static void io_req_task_queue(struct io_kiocb
*req
)
2059 req
->io_task_work
.func
= io_req_task_submit
;
2060 io_req_task_work_add(req
);
2063 static void io_req_task_queue_reissue(struct io_kiocb
*req
)
2065 req
->io_task_work
.func
= io_queue_async_work
;
2066 io_req_task_work_add(req
);
2069 static inline void io_queue_next(struct io_kiocb
*req
)
2071 struct io_kiocb
*nxt
= io_req_find_next(req
);
2074 io_req_task_queue(nxt
);
2077 static void io_free_req(struct io_kiocb
*req
)
2084 struct task_struct
*task
;
2089 static inline void io_init_req_batch(struct req_batch
*rb
)
2096 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2097 struct req_batch
*rb
)
2100 io_put_task(rb
->task
, rb
->task_refs
);
2102 percpu_ref_put_many(&ctx
->refs
, rb
->ctx_refs
);
2105 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
,
2106 struct io_submit_state
*state
)
2109 io_dismantle_req(req
);
2111 if (req
->task
!= rb
->task
) {
2113 io_put_task(rb
->task
, rb
->task_refs
);
2114 rb
->task
= req
->task
;
2120 if (state
->free_reqs
!= ARRAY_SIZE(state
->reqs
))
2121 state
->reqs
[state
->free_reqs
++] = req
;
2123 list_add(&req
->compl.list
, &state
->comp
.free_list
);
2126 static void io_submit_flush_completions(struct io_ring_ctx
*ctx
)
2128 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
2130 struct req_batch rb
;
2132 spin_lock_irq(&ctx
->completion_lock
);
2133 for (i
= 0; i
< nr
; i
++) {
2134 struct io_kiocb
*req
= cs
->reqs
[i
];
2136 __io_cqring_fill_event(ctx
, req
->user_data
, req
->result
,
2139 io_commit_cqring(ctx
);
2140 spin_unlock_irq(&ctx
->completion_lock
);
2141 io_cqring_ev_posted(ctx
);
2143 io_init_req_batch(&rb
);
2144 for (i
= 0; i
< nr
; i
++) {
2145 struct io_kiocb
*req
= cs
->reqs
[i
];
2147 /* submission and completion refs */
2148 if (req_ref_sub_and_test(req
, 2))
2149 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2152 io_req_free_batch_finish(ctx
, &rb
);
2157 * Drop reference to request, return next in chain (if there is one) if this
2158 * was the last reference to this request.
2160 static inline struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2162 struct io_kiocb
*nxt
= NULL
;
2164 if (req_ref_put_and_test(req
)) {
2165 nxt
= io_req_find_next(req
);
2171 static inline void io_put_req(struct io_kiocb
*req
)
2173 if (req_ref_put_and_test(req
))
2177 static void io_free_req_deferred(struct io_kiocb
*req
)
2179 req
->io_task_work
.func
= io_free_req
;
2180 io_req_task_work_add(req
);
2183 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2185 if (req_ref_sub_and_test(req
, refs
))
2186 io_free_req_deferred(req
);
2189 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
)
2191 /* See comment at the top of this file */
2193 return __io_cqring_events(ctx
);
2196 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2198 struct io_rings
*rings
= ctx
->rings
;
2200 /* make sure SQ entry isn't read before tail */
2201 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2204 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2206 unsigned int cflags
;
2208 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2209 cflags
|= IORING_CQE_F_BUFFER
;
2210 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2215 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2217 struct io_buffer
*kbuf
;
2219 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2220 return io_put_kbuf(req
, kbuf
);
2223 static inline bool io_run_task_work(void)
2225 if (current
->task_works
) {
2226 __set_current_state(TASK_RUNNING
);
2235 * Find and free completed poll iocbs
2237 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2238 struct list_head
*done
, bool resubmit
)
2240 struct req_batch rb
;
2241 struct io_kiocb
*req
;
2243 /* order with ->result store in io_complete_rw_iopoll() */
2246 io_init_req_batch(&rb
);
2247 while (!list_empty(done
)) {
2250 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2251 list_del(&req
->inflight_entry
);
2253 if (READ_ONCE(req
->result
) == -EAGAIN
&& resubmit
&&
2254 !(req
->flags
& REQ_F_DONT_REISSUE
)) {
2255 req
->iopoll_completed
= 0;
2257 io_req_task_queue_reissue(req
);
2261 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2262 cflags
= io_put_rw_kbuf(req
);
2264 __io_cqring_fill_event(ctx
, req
->user_data
, req
->result
, cflags
);
2267 if (req_ref_put_and_test(req
))
2268 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2271 io_commit_cqring(ctx
);
2272 io_cqring_ev_posted_iopoll(ctx
);
2273 io_req_free_batch_finish(ctx
, &rb
);
2276 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2277 long min
, bool resubmit
)
2279 struct io_kiocb
*req
, *tmp
;
2285 * Only spin for completions if we don't have multiple devices hanging
2286 * off our complete list, and we're under the requested amount.
2288 spin
= !ctx
->poll_multi_queue
&& *nr_events
< min
;
2291 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2292 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2295 * Move completed and retryable entries to our local lists.
2296 * If we find a request that requires polling, break out
2297 * and complete those lists first, if we have entries there.
2299 if (READ_ONCE(req
->iopoll_completed
)) {
2300 list_move_tail(&req
->inflight_entry
, &done
);
2303 if (!list_empty(&done
))
2306 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2310 /* iopoll may have completed current req */
2311 if (READ_ONCE(req
->iopoll_completed
))
2312 list_move_tail(&req
->inflight_entry
, &done
);
2319 if (!list_empty(&done
))
2320 io_iopoll_complete(ctx
, nr_events
, &done
, resubmit
);
2326 * We can't just wait for polled events to come to us, we have to actively
2327 * find and complete them.
2329 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2331 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2334 mutex_lock(&ctx
->uring_lock
);
2335 while (!list_empty(&ctx
->iopoll_list
)) {
2336 unsigned int nr_events
= 0;
2338 io_do_iopoll(ctx
, &nr_events
, 0, false);
2340 /* let it sleep and repeat later if can't complete a request */
2344 * Ensure we allow local-to-the-cpu processing to take place,
2345 * in this case we need to ensure that we reap all events.
2346 * Also let task_work, etc. to progress by releasing the mutex
2348 if (need_resched()) {
2349 mutex_unlock(&ctx
->uring_lock
);
2351 mutex_lock(&ctx
->uring_lock
);
2354 mutex_unlock(&ctx
->uring_lock
);
2357 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2359 unsigned int nr_events
= 0;
2363 * We disallow the app entering submit/complete with polling, but we
2364 * still need to lock the ring to prevent racing with polled issue
2365 * that got punted to a workqueue.
2367 mutex_lock(&ctx
->uring_lock
);
2369 * Don't enter poll loop if we already have events pending.
2370 * If we do, we can potentially be spinning for commands that
2371 * already triggered a CQE (eg in error).
2373 if (test_bit(0, &ctx
->check_cq_overflow
))
2374 __io_cqring_overflow_flush(ctx
, false);
2375 if (io_cqring_events(ctx
))
2379 * If a submit got punted to a workqueue, we can have the
2380 * application entering polling for a command before it gets
2381 * issued. That app will hold the uring_lock for the duration
2382 * of the poll right here, so we need to take a breather every
2383 * now and then to ensure that the issue has a chance to add
2384 * the poll to the issued list. Otherwise we can spin here
2385 * forever, while the workqueue is stuck trying to acquire the
2388 if (list_empty(&ctx
->iopoll_list
)) {
2389 u32 tail
= ctx
->cached_cq_tail
;
2391 mutex_unlock(&ctx
->uring_lock
);
2393 mutex_lock(&ctx
->uring_lock
);
2395 /* some requests don't go through iopoll_list */
2396 if (tail
!= ctx
->cached_cq_tail
||
2397 list_empty(&ctx
->iopoll_list
))
2400 ret
= io_do_iopoll(ctx
, &nr_events
, min
, true);
2401 } while (!ret
&& nr_events
< min
&& !need_resched());
2403 mutex_unlock(&ctx
->uring_lock
);
2407 static void kiocb_end_write(struct io_kiocb
*req
)
2410 * Tell lockdep we inherited freeze protection from submission
2413 if (req
->flags
& REQ_F_ISREG
) {
2414 struct super_block
*sb
= file_inode(req
->file
)->i_sb
;
2416 __sb_writers_acquired(sb
, SB_FREEZE_WRITE
);
2422 static bool io_resubmit_prep(struct io_kiocb
*req
)
2424 struct io_async_rw
*rw
= req
->async_data
;
2427 return !io_req_prep_async(req
);
2428 /* may have left rw->iter inconsistent on -EIOCBQUEUED */
2429 iov_iter_revert(&rw
->iter
, req
->result
- iov_iter_count(&rw
->iter
));
2433 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2435 umode_t mode
= file_inode(req
->file
)->i_mode
;
2436 struct io_ring_ctx
*ctx
= req
->ctx
;
2438 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2440 if ((req
->flags
& REQ_F_NOWAIT
) || (io_wq_current_is_worker() &&
2441 !(ctx
->flags
& IORING_SETUP_IOPOLL
)))
2444 * If ref is dying, we might be running poll reap from the exit work.
2445 * Don't attempt to reissue from that path, just let it fail with
2448 if (percpu_ref_is_dying(&ctx
->refs
))
2453 static bool io_resubmit_prep(struct io_kiocb
*req
)
2457 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2463 static void io_fallback_req_func(struct work_struct
*work
)
2465 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
2466 fallback_work
.work
);
2467 struct llist_node
*node
= llist_del_all(&ctx
->fallback_llist
);
2468 struct io_kiocb
*req
, *tmp
;
2470 llist_for_each_entry_safe(req
, tmp
, node
, io_task_work
.fallback_node
)
2471 req
->io_task_work
.func(req
);
2474 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2475 unsigned int issue_flags
)
2479 if (req
->rw
.kiocb
.ki_flags
& IOCB_WRITE
)
2480 kiocb_end_write(req
);
2481 if (res
!= req
->result
) {
2482 if ((res
== -EAGAIN
|| res
== -EOPNOTSUPP
) &&
2483 io_rw_should_reissue(req
)) {
2484 req
->flags
|= REQ_F_REISSUE
;
2489 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2490 cflags
= io_put_rw_kbuf(req
);
2491 __io_req_complete(req
, issue_flags
, res
, cflags
);
2494 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2496 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2498 __io_complete_rw(req
, res
, res2
, 0);
2501 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2503 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2505 if (kiocb
->ki_flags
& IOCB_WRITE
)
2506 kiocb_end_write(req
);
2507 if (unlikely(res
!= req
->result
)) {
2508 if (!(res
== -EAGAIN
&& io_rw_should_reissue(req
) &&
2509 io_resubmit_prep(req
))) {
2511 req
->flags
|= REQ_F_DONT_REISSUE
;
2515 WRITE_ONCE(req
->result
, res
);
2516 /* order with io_iopoll_complete() checking ->result */
2518 WRITE_ONCE(req
->iopoll_completed
, 1);
2522 * After the iocb has been issued, it's safe to be found on the poll list.
2523 * Adding the kiocb to the list AFTER submission ensures that we don't
2524 * find it from a io_do_iopoll() thread before the issuer is done
2525 * accessing the kiocb cookie.
2527 static void io_iopoll_req_issued(struct io_kiocb
*req
)
2529 struct io_ring_ctx
*ctx
= req
->ctx
;
2530 const bool in_async
= io_wq_current_is_worker();
2532 /* workqueue context doesn't hold uring_lock, grab it now */
2533 if (unlikely(in_async
))
2534 mutex_lock(&ctx
->uring_lock
);
2537 * Track whether we have multiple files in our lists. This will impact
2538 * how we do polling eventually, not spinning if we're on potentially
2539 * different devices.
2541 if (list_empty(&ctx
->iopoll_list
)) {
2542 ctx
->poll_multi_queue
= false;
2543 } else if (!ctx
->poll_multi_queue
) {
2544 struct io_kiocb
*list_req
;
2545 unsigned int queue_num0
, queue_num1
;
2547 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2550 if (list_req
->file
!= req
->file
) {
2551 ctx
->poll_multi_queue
= true;
2553 queue_num0
= blk_qc_t_to_queue_num(list_req
->rw
.kiocb
.ki_cookie
);
2554 queue_num1
= blk_qc_t_to_queue_num(req
->rw
.kiocb
.ki_cookie
);
2555 if (queue_num0
!= queue_num1
)
2556 ctx
->poll_multi_queue
= true;
2561 * For fast devices, IO may have already completed. If it has, add
2562 * it to the front so we find it first.
2564 if (READ_ONCE(req
->iopoll_completed
))
2565 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2567 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2569 if (unlikely(in_async
)) {
2571 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
2572 * in sq thread task context or in io worker task context. If
2573 * current task context is sq thread, we don't need to check
2574 * whether should wake up sq thread.
2576 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2577 wq_has_sleeper(&ctx
->sq_data
->wait
))
2578 wake_up(&ctx
->sq_data
->wait
);
2580 mutex_unlock(&ctx
->uring_lock
);
2584 static inline void io_state_file_put(struct io_submit_state
*state
)
2586 if (state
->file_refs
) {
2587 fput_many(state
->file
, state
->file_refs
);
2588 state
->file_refs
= 0;
2593 * Get as many references to a file as we have IOs left in this submission,
2594 * assuming most submissions are for one file, or at least that each file
2595 * has more than one submission.
2597 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2602 if (state
->file_refs
) {
2603 if (state
->fd
== fd
) {
2607 io_state_file_put(state
);
2609 state
->file
= fget_many(fd
, state
->ios_left
);
2610 if (unlikely(!state
->file
))
2614 state
->file_refs
= state
->ios_left
- 1;
2618 static bool io_bdev_nowait(struct block_device
*bdev
)
2620 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2624 * If we tracked the file through the SCM inflight mechanism, we could support
2625 * any file. For now, just ensure that anything potentially problematic is done
2628 static bool __io_file_supports_async(struct file
*file
, int rw
)
2630 umode_t mode
= file_inode(file
)->i_mode
;
2632 if (S_ISBLK(mode
)) {
2633 if (IS_ENABLED(CONFIG_BLOCK
) &&
2634 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2640 if (S_ISREG(mode
)) {
2641 if (IS_ENABLED(CONFIG_BLOCK
) &&
2642 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2643 file
->f_op
!= &io_uring_fops
)
2648 /* any ->read/write should understand O_NONBLOCK */
2649 if (file
->f_flags
& O_NONBLOCK
)
2652 if (!(file
->f_mode
& FMODE_NOWAIT
))
2656 return file
->f_op
->read_iter
!= NULL
;
2658 return file
->f_op
->write_iter
!= NULL
;
2661 static bool io_file_supports_async(struct io_kiocb
*req
, int rw
)
2663 if (rw
== READ
&& (req
->flags
& REQ_F_ASYNC_READ
))
2665 else if (rw
== WRITE
&& (req
->flags
& REQ_F_ASYNC_WRITE
))
2668 return __io_file_supports_async(req
->file
, rw
);
2671 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2673 struct io_ring_ctx
*ctx
= req
->ctx
;
2674 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2675 struct file
*file
= req
->file
;
2679 if (!(req
->flags
& REQ_F_ISREG
) && S_ISREG(file_inode(file
)->i_mode
))
2680 req
->flags
|= REQ_F_ISREG
;
2682 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2683 if (kiocb
->ki_pos
== -1 && !(file
->f_mode
& FMODE_STREAM
)) {
2684 req
->flags
|= REQ_F_CUR_POS
;
2685 kiocb
->ki_pos
= file
->f_pos
;
2687 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2688 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2689 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2693 /* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
2694 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) || (file
->f_flags
& O_NONBLOCK
))
2695 req
->flags
|= REQ_F_NOWAIT
;
2697 ioprio
= READ_ONCE(sqe
->ioprio
);
2699 ret
= ioprio_check_cap(ioprio
);
2703 kiocb
->ki_ioprio
= ioprio
;
2705 kiocb
->ki_ioprio
= get_current_ioprio();
2707 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2708 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2709 !kiocb
->ki_filp
->f_op
->iopoll
)
2712 kiocb
->ki_flags
|= IOCB_HIPRI
;
2713 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2714 req
->iopoll_completed
= 0;
2716 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2718 kiocb
->ki_complete
= io_complete_rw
;
2721 if (req
->opcode
== IORING_OP_READ_FIXED
||
2722 req
->opcode
== IORING_OP_WRITE_FIXED
) {
2724 io_req_set_rsrc_node(req
);
2727 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2728 req
->rw
.len
= READ_ONCE(sqe
->len
);
2729 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2733 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2739 case -ERESTARTNOINTR
:
2740 case -ERESTARTNOHAND
:
2741 case -ERESTART_RESTARTBLOCK
:
2743 * We can't just restart the syscall, since previously
2744 * submitted sqes may already be in progress. Just fail this
2750 kiocb
->ki_complete(kiocb
, ret
, 0);
2754 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2755 unsigned int issue_flags
)
2757 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2758 struct io_async_rw
*io
= req
->async_data
;
2759 bool check_reissue
= kiocb
->ki_complete
== io_complete_rw
;
2761 /* add previously done IO, if any */
2762 if (io
&& io
->bytes_done
> 0) {
2764 ret
= io
->bytes_done
;
2766 ret
+= io
->bytes_done
;
2769 if (req
->flags
& REQ_F_CUR_POS
)
2770 req
->file
->f_pos
= kiocb
->ki_pos
;
2771 if (ret
>= 0 && check_reissue
)
2772 __io_complete_rw(req
, ret
, 0, issue_flags
);
2774 io_rw_done(kiocb
, ret
);
2776 if (check_reissue
&& (req
->flags
& REQ_F_REISSUE
)) {
2777 req
->flags
&= ~REQ_F_REISSUE
;
2778 if (io_resubmit_prep(req
)) {
2780 io_req_task_queue_reissue(req
);
2785 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2786 cflags
= io_put_rw_kbuf(req
);
2787 __io_req_complete(req
, issue_flags
, ret
, cflags
);
2792 static int __io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
,
2793 struct io_mapped_ubuf
*imu
)
2795 size_t len
= req
->rw
.len
;
2796 u64 buf_end
, buf_addr
= req
->rw
.addr
;
2799 if (unlikely(check_add_overflow(buf_addr
, (u64
)len
, &buf_end
)))
2801 /* not inside the mapped region */
2802 if (unlikely(buf_addr
< imu
->ubuf
|| buf_end
> imu
->ubuf_end
))
2806 * May not be a start of buffer, set size appropriately
2807 * and advance us to the beginning.
2809 offset
= buf_addr
- imu
->ubuf
;
2810 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2814 * Don't use iov_iter_advance() here, as it's really slow for
2815 * using the latter parts of a big fixed buffer - it iterates
2816 * over each segment manually. We can cheat a bit here, because
2819 * 1) it's a BVEC iter, we set it up
2820 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2821 * first and last bvec
2823 * So just find our index, and adjust the iterator afterwards.
2824 * If the offset is within the first bvec (or the whole first
2825 * bvec, just use iov_iter_advance(). This makes it easier
2826 * since we can just skip the first segment, which may not
2827 * be PAGE_SIZE aligned.
2829 const struct bio_vec
*bvec
= imu
->bvec
;
2831 if (offset
<= bvec
->bv_len
) {
2832 iov_iter_advance(iter
, offset
);
2834 unsigned long seg_skip
;
2836 /* skip first vec */
2837 offset
-= bvec
->bv_len
;
2838 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2840 iter
->bvec
= bvec
+ seg_skip
;
2841 iter
->nr_segs
-= seg_skip
;
2842 iter
->count
-= bvec
->bv_len
+ offset
;
2843 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2850 static int io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
)
2852 struct io_ring_ctx
*ctx
= req
->ctx
;
2853 struct io_mapped_ubuf
*imu
= req
->imu
;
2854 u16 index
, buf_index
= req
->buf_index
;
2857 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2859 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2860 imu
= READ_ONCE(ctx
->user_bufs
[index
]);
2863 return __io_import_fixed(req
, rw
, iter
, imu
);
2866 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2869 mutex_unlock(&ctx
->uring_lock
);
2872 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2875 * "Normal" inline submissions always hold the uring_lock, since we
2876 * grab it from the system call. Same is true for the SQPOLL offload.
2877 * The only exception is when we've detached the request and issue it
2878 * from an async worker thread, grab the lock for that case.
2881 mutex_lock(&ctx
->uring_lock
);
2884 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2885 int bgid
, struct io_buffer
*kbuf
,
2888 struct io_buffer
*head
;
2890 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2893 io_ring_submit_lock(req
->ctx
, needs_lock
);
2895 lockdep_assert_held(&req
->ctx
->uring_lock
);
2897 head
= xa_load(&req
->ctx
->io_buffers
, bgid
);
2899 if (!list_empty(&head
->list
)) {
2900 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2902 list_del(&kbuf
->list
);
2905 xa_erase(&req
->ctx
->io_buffers
, bgid
);
2907 if (*len
> kbuf
->len
)
2910 kbuf
= ERR_PTR(-ENOBUFS
);
2913 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2918 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2921 struct io_buffer
*kbuf
;
2924 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2925 bgid
= req
->buf_index
;
2926 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2929 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2930 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2931 return u64_to_user_ptr(kbuf
->addr
);
2934 #ifdef CONFIG_COMPAT
2935 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2938 struct compat_iovec __user
*uiov
;
2939 compat_ssize_t clen
;
2943 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2944 if (!access_ok(uiov
, sizeof(*uiov
)))
2946 if (__get_user(clen
, &uiov
->iov_len
))
2952 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2954 return PTR_ERR(buf
);
2955 iov
[0].iov_base
= buf
;
2956 iov
[0].iov_len
= (compat_size_t
) len
;
2961 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2964 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2968 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
2971 len
= iov
[0].iov_len
;
2974 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2976 return PTR_ERR(buf
);
2977 iov
[0].iov_base
= buf
;
2978 iov
[0].iov_len
= len
;
2982 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2985 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
2986 struct io_buffer
*kbuf
;
2988 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2989 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
2990 iov
[0].iov_len
= kbuf
->len
;
2993 if (req
->rw
.len
!= 1)
2996 #ifdef CONFIG_COMPAT
2997 if (req
->ctx
->compat
)
2998 return io_compat_import(req
, iov
, needs_lock
);
3001 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3004 static int io_import_iovec(int rw
, struct io_kiocb
*req
, struct iovec
**iovec
,
3005 struct iov_iter
*iter
, bool needs_lock
)
3007 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3008 size_t sqe_len
= req
->rw
.len
;
3009 u8 opcode
= req
->opcode
;
3012 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3014 return io_import_fixed(req
, rw
, iter
);
3017 /* buffer index only valid with fixed read/write, or buffer select */
3018 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3021 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3022 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3023 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3025 return PTR_ERR(buf
);
3026 req
->rw
.len
= sqe_len
;
3029 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3034 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3035 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3037 iov_iter_init(iter
, rw
, *iovec
, 1, (*iovec
)->iov_len
);
3042 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3046 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3048 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3052 * For files that don't have ->read_iter() and ->write_iter(), handle them
3053 * by looping over ->read() or ->write() manually.
3055 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3057 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3058 struct file
*file
= req
->file
;
3062 * Don't support polled IO through this interface, and we can't
3063 * support non-blocking either. For the latter, this just causes
3064 * the kiocb to be handled from an async context.
3066 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3068 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3071 while (iov_iter_count(iter
)) {
3075 if (!iov_iter_is_bvec(iter
)) {
3076 iovec
= iov_iter_iovec(iter
);
3078 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3079 iovec
.iov_len
= req
->rw
.len
;
3083 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3084 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3086 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3087 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3096 if (nr
!= iovec
.iov_len
)
3100 iov_iter_advance(iter
, nr
);
3106 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3107 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3109 struct io_async_rw
*rw
= req
->async_data
;
3111 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3112 rw
->free_iovec
= iovec
;
3114 /* can only be fixed buffers, no need to do anything */
3115 if (iov_iter_is_bvec(iter
))
3118 unsigned iov_off
= 0;
3120 rw
->iter
.iov
= rw
->fast_iov
;
3121 if (iter
->iov
!= fast_iov
) {
3122 iov_off
= iter
->iov
- fast_iov
;
3123 rw
->iter
.iov
+= iov_off
;
3125 if (rw
->fast_iov
!= fast_iov
)
3126 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3127 sizeof(struct iovec
) * iter
->nr_segs
);
3129 req
->flags
|= REQ_F_NEED_CLEANUP
;
3133 static inline int io_alloc_async_data(struct io_kiocb
*req
)
3135 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3136 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3137 return req
->async_data
== NULL
;
3140 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3141 const struct iovec
*fast_iov
,
3142 struct iov_iter
*iter
, bool force
)
3144 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_setup
)
3146 if (!req
->async_data
) {
3147 if (io_alloc_async_data(req
)) {
3152 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3157 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3159 struct io_async_rw
*iorw
= req
->async_data
;
3160 struct iovec
*iov
= iorw
->fast_iov
;
3163 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3164 if (unlikely(ret
< 0))
3167 iorw
->bytes_done
= 0;
3168 iorw
->free_iovec
= iov
;
3170 req
->flags
|= REQ_F_NEED_CLEANUP
;
3174 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3176 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3178 return io_prep_rw(req
, sqe
);
3182 * This is our waitqueue callback handler, registered through lock_page_async()
3183 * when we initially tried to do the IO with the iocb armed our waitqueue.
3184 * This gets called when the page is unlocked, and we generally expect that to
3185 * happen when the page IO is completed and the page is now uptodate. This will
3186 * queue a task_work based retry of the operation, attempting to copy the data
3187 * again. If the latter fails because the page was NOT uptodate, then we will
3188 * do a thread based blocking retry of the operation. That's the unexpected
3191 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3192 int sync
, void *arg
)
3194 struct wait_page_queue
*wpq
;
3195 struct io_kiocb
*req
= wait
->private;
3196 struct wait_page_key
*key
= arg
;
3198 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3200 if (!wake_page_match(wpq
, key
))
3203 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3204 list_del_init(&wait
->entry
);
3206 /* submit ref gets dropped, acquire a new one */
3208 io_req_task_queue(req
);
3213 * This controls whether a given IO request should be armed for async page
3214 * based retry. If we return false here, the request is handed to the async
3215 * worker threads for retry. If we're doing buffered reads on a regular file,
3216 * we prepare a private wait_page_queue entry and retry the operation. This
3217 * will either succeed because the page is now uptodate and unlocked, or it
3218 * will register a callback when the page is unlocked at IO completion. Through
3219 * that callback, io_uring uses task_work to setup a retry of the operation.
3220 * That retry will attempt the buffered read again. The retry will generally
3221 * succeed, or in rare cases where it fails, we then fall back to using the
3222 * async worker threads for a blocking retry.
3224 static bool io_rw_should_retry(struct io_kiocb
*req
)
3226 struct io_async_rw
*rw
= req
->async_data
;
3227 struct wait_page_queue
*wait
= &rw
->wpq
;
3228 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3230 /* never retry for NOWAIT, we just complete with -EAGAIN */
3231 if (req
->flags
& REQ_F_NOWAIT
)
3234 /* Only for buffered IO */
3235 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3239 * just use poll if we can, and don't attempt if the fs doesn't
3240 * support callback based unlocks
3242 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3245 wait
->wait
.func
= io_async_buf_func
;
3246 wait
->wait
.private = req
;
3247 wait
->wait
.flags
= 0;
3248 INIT_LIST_HEAD(&wait
->wait
.entry
);
3249 kiocb
->ki_flags
|= IOCB_WAITQ
;
3250 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3251 kiocb
->ki_waitq
= wait
;
3255 static inline int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3257 if (req
->file
->f_op
->read_iter
)
3258 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3259 else if (req
->file
->f_op
->read
)
3260 return loop_rw_iter(READ
, req
, iter
);
3265 static int io_read(struct io_kiocb
*req
, unsigned int issue_flags
)
3267 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3268 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3269 struct iov_iter __iter
, *iter
= &__iter
;
3270 struct io_async_rw
*rw
= req
->async_data
;
3271 ssize_t io_size
, ret
, ret2
;
3272 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3278 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3282 io_size
= iov_iter_count(iter
);
3283 req
->result
= io_size
;
3285 /* Ensure we clear previously set non-block flag */
3286 if (!force_nonblock
)
3287 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3289 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3291 /* If the file doesn't support async, just async punt */
3292 if (force_nonblock
&& !io_file_supports_async(req
, READ
)) {
3293 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3294 return ret
?: -EAGAIN
;
3297 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3298 if (unlikely(ret
)) {
3303 ret
= io_iter_do_read(req
, iter
);
3305 if (ret
== -EAGAIN
|| (req
->flags
& REQ_F_REISSUE
)) {
3306 req
->flags
&= ~REQ_F_REISSUE
;
3307 /* IOPOLL retry should happen for io-wq threads */
3308 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3310 /* no retry on NONBLOCK nor RWF_NOWAIT */
3311 if (req
->flags
& REQ_F_NOWAIT
)
3313 /* some cases will consume bytes even on error returns */
3314 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3316 } else if (ret
== -EIOCBQUEUED
) {
3318 } else if (ret
<= 0 || ret
== io_size
|| !force_nonblock
||
3319 (req
->flags
& REQ_F_NOWAIT
) || !(req
->flags
& REQ_F_ISREG
)) {
3320 /* read all, failed, already did sync or don't want to retry */
3324 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3329 rw
= req
->async_data
;
3330 /* now use our persistent iterator, if we aren't already */
3335 rw
->bytes_done
+= ret
;
3336 /* if we can retry, do so with the callbacks armed */
3337 if (!io_rw_should_retry(req
)) {
3338 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3343 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3344 * we get -EIOCBQUEUED, then we'll get a notification when the
3345 * desired page gets unlocked. We can also get a partial read
3346 * here, and if we do, then just retry at the new offset.
3348 ret
= io_iter_do_read(req
, iter
);
3349 if (ret
== -EIOCBQUEUED
)
3351 /* we got some bytes, but not all. retry. */
3352 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3353 } while (ret
> 0 && ret
< io_size
);
3355 kiocb_done(kiocb
, ret
, issue_flags
);
3357 /* it's faster to check here then delegate to kfree */
3363 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3365 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3367 return io_prep_rw(req
, sqe
);
3370 static int io_write(struct io_kiocb
*req
, unsigned int issue_flags
)
3372 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3373 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3374 struct iov_iter __iter
, *iter
= &__iter
;
3375 struct io_async_rw
*rw
= req
->async_data
;
3376 ssize_t ret
, ret2
, io_size
;
3377 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3383 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3387 io_size
= iov_iter_count(iter
);
3388 req
->result
= io_size
;
3390 /* Ensure we clear previously set non-block flag */
3391 if (!force_nonblock
)
3392 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3394 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3396 /* If the file doesn't support async, just async punt */
3397 if (force_nonblock
&& !io_file_supports_async(req
, WRITE
))
3400 /* file path doesn't support NOWAIT for non-direct_IO */
3401 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3402 (req
->flags
& REQ_F_ISREG
))
3405 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), io_size
);
3410 * Open-code file_start_write here to grab freeze protection,
3411 * which will be released by another thread in
3412 * io_complete_rw(). Fool lockdep by telling it the lock got
3413 * released so that it doesn't complain about the held lock when
3414 * we return to userspace.
3416 if (req
->flags
& REQ_F_ISREG
) {
3417 sb_start_write(file_inode(req
->file
)->i_sb
);
3418 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3421 kiocb
->ki_flags
|= IOCB_WRITE
;
3423 if (req
->file
->f_op
->write_iter
)
3424 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3425 else if (req
->file
->f_op
->write
)
3426 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3430 if (req
->flags
& REQ_F_REISSUE
) {
3431 req
->flags
&= ~REQ_F_REISSUE
;
3436 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3437 * retry them without IOCB_NOWAIT.
3439 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3441 /* no retry on NONBLOCK nor RWF_NOWAIT */
3442 if (ret2
== -EAGAIN
&& (req
->flags
& REQ_F_NOWAIT
))
3444 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3445 /* IOPOLL retry should happen for io-wq threads */
3446 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3449 kiocb_done(kiocb
, ret2
, issue_flags
);
3452 /* some cases will consume bytes even on error returns */
3453 iov_iter_revert(iter
, io_size
- iov_iter_count(iter
));
3454 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3455 return ret
?: -EAGAIN
;
3458 /* it's reportedly faster than delegating the null check to kfree() */
3464 static int io_renameat_prep(struct io_kiocb
*req
,
3465 const struct io_uring_sqe
*sqe
)
3467 struct io_rename
*ren
= &req
->rename
;
3468 const char __user
*oldf
, *newf
;
3470 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3472 if (sqe
->ioprio
|| sqe
->buf_index
)
3474 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3477 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3478 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3479 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3480 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3481 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3483 ren
->oldpath
= getname(oldf
);
3484 if (IS_ERR(ren
->oldpath
))
3485 return PTR_ERR(ren
->oldpath
);
3487 ren
->newpath
= getname(newf
);
3488 if (IS_ERR(ren
->newpath
)) {
3489 putname(ren
->oldpath
);
3490 return PTR_ERR(ren
->newpath
);
3493 req
->flags
|= REQ_F_NEED_CLEANUP
;
3497 static int io_renameat(struct io_kiocb
*req
, unsigned int issue_flags
)
3499 struct io_rename
*ren
= &req
->rename
;
3502 if (issue_flags
& IO_URING_F_NONBLOCK
)
3505 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3506 ren
->newpath
, ren
->flags
);
3508 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3511 io_req_complete(req
, ret
);
3515 static int io_unlinkat_prep(struct io_kiocb
*req
,
3516 const struct io_uring_sqe
*sqe
)
3518 struct io_unlink
*un
= &req
->unlink
;
3519 const char __user
*fname
;
3521 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3523 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
3525 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3528 un
->dfd
= READ_ONCE(sqe
->fd
);
3530 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3531 if (un
->flags
& ~AT_REMOVEDIR
)
3534 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3535 un
->filename
= getname(fname
);
3536 if (IS_ERR(un
->filename
))
3537 return PTR_ERR(un
->filename
);
3539 req
->flags
|= REQ_F_NEED_CLEANUP
;
3543 static int io_unlinkat(struct io_kiocb
*req
, unsigned int issue_flags
)
3545 struct io_unlink
*un
= &req
->unlink
;
3548 if (issue_flags
& IO_URING_F_NONBLOCK
)
3551 if (un
->flags
& AT_REMOVEDIR
)
3552 ret
= do_rmdir(un
->dfd
, un
->filename
);
3554 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3556 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3559 io_req_complete(req
, ret
);
3563 static int io_shutdown_prep(struct io_kiocb
*req
,
3564 const struct io_uring_sqe
*sqe
)
3566 #if defined(CONFIG_NET)
3567 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3569 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3573 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3580 static int io_shutdown(struct io_kiocb
*req
, unsigned int issue_flags
)
3582 #if defined(CONFIG_NET)
3583 struct socket
*sock
;
3586 if (issue_flags
& IO_URING_F_NONBLOCK
)
3589 sock
= sock_from_file(req
->file
);
3590 if (unlikely(!sock
))
3593 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3596 io_req_complete(req
, ret
);
3603 static int __io_splice_prep(struct io_kiocb
*req
,
3604 const struct io_uring_sqe
*sqe
)
3606 struct io_splice
*sp
= &req
->splice
;
3607 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3609 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3613 sp
->len
= READ_ONCE(sqe
->len
);
3614 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3616 if (unlikely(sp
->flags
& ~valid_flags
))
3619 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3620 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3623 req
->flags
|= REQ_F_NEED_CLEANUP
;
3627 static int io_tee_prep(struct io_kiocb
*req
,
3628 const struct io_uring_sqe
*sqe
)
3630 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3632 return __io_splice_prep(req
, sqe
);
3635 static int io_tee(struct io_kiocb
*req
, unsigned int issue_flags
)
3637 struct io_splice
*sp
= &req
->splice
;
3638 struct file
*in
= sp
->file_in
;
3639 struct file
*out
= sp
->file_out
;
3640 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3643 if (issue_flags
& IO_URING_F_NONBLOCK
)
3646 ret
= do_tee(in
, out
, sp
->len
, flags
);
3648 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
3650 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3654 io_req_complete(req
, ret
);
3658 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3660 struct io_splice
*sp
= &req
->splice
;
3662 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3663 sp
->off_out
= READ_ONCE(sqe
->off
);
3664 return __io_splice_prep(req
, sqe
);
3667 static int io_splice(struct io_kiocb
*req
, unsigned int issue_flags
)
3669 struct io_splice
*sp
= &req
->splice
;
3670 struct file
*in
= sp
->file_in
;
3671 struct file
*out
= sp
->file_out
;
3672 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3673 loff_t
*poff_in
, *poff_out
;
3676 if (issue_flags
& IO_URING_F_NONBLOCK
)
3679 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3680 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3683 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3685 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
3687 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3691 io_req_complete(req
, ret
);
3696 * IORING_OP_NOP just posts a completion event, nothing else.
3698 static int io_nop(struct io_kiocb
*req
, unsigned int issue_flags
)
3700 struct io_ring_ctx
*ctx
= req
->ctx
;
3702 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3705 __io_req_complete(req
, issue_flags
, 0, 0);
3709 static int io_fsync_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3711 struct io_ring_ctx
*ctx
= req
->ctx
;
3716 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3718 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3721 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3722 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3725 req
->sync
.off
= READ_ONCE(sqe
->off
);
3726 req
->sync
.len
= READ_ONCE(sqe
->len
);
3730 static int io_fsync(struct io_kiocb
*req
, unsigned int issue_flags
)
3732 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3735 /* fsync always requires a blocking context */
3736 if (issue_flags
& IO_URING_F_NONBLOCK
)
3739 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3740 end
> 0 ? end
: LLONG_MAX
,
3741 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3744 io_req_complete(req
, ret
);
3748 static int io_fallocate_prep(struct io_kiocb
*req
,
3749 const struct io_uring_sqe
*sqe
)
3751 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3753 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3756 req
->sync
.off
= READ_ONCE(sqe
->off
);
3757 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3758 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3762 static int io_fallocate(struct io_kiocb
*req
, unsigned int issue_flags
)
3766 /* fallocate always requiring blocking context */
3767 if (issue_flags
& IO_URING_F_NONBLOCK
)
3769 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3773 io_req_complete(req
, ret
);
3777 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3779 const char __user
*fname
;
3782 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3784 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3787 /* open.how should be already initialised */
3788 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3789 req
->open
.how
.flags
|= O_LARGEFILE
;
3791 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3792 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3793 req
->open
.filename
= getname(fname
);
3794 if (IS_ERR(req
->open
.filename
)) {
3795 ret
= PTR_ERR(req
->open
.filename
);
3796 req
->open
.filename
= NULL
;
3799 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3800 req
->flags
|= REQ_F_NEED_CLEANUP
;
3804 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3808 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3810 mode
= READ_ONCE(sqe
->len
);
3811 flags
= READ_ONCE(sqe
->open_flags
);
3812 req
->open
.how
= build_open_how(flags
, mode
);
3813 return __io_openat_prep(req
, sqe
);
3816 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3818 struct open_how __user
*how
;
3822 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3824 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3825 len
= READ_ONCE(sqe
->len
);
3826 if (len
< OPEN_HOW_SIZE_VER0
)
3829 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3834 return __io_openat_prep(req
, sqe
);
3837 static int io_openat2(struct io_kiocb
*req
, unsigned int issue_flags
)
3839 struct open_flags op
;
3842 bool resolve_nonblock
;
3845 ret
= build_open_flags(&req
->open
.how
, &op
);
3848 nonblock_set
= op
.open_flag
& O_NONBLOCK
;
3849 resolve_nonblock
= req
->open
.how
.resolve
& RESOLVE_CACHED
;
3850 if (issue_flags
& IO_URING_F_NONBLOCK
) {
3852 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
3853 * it'll always -EAGAIN
3855 if (req
->open
.how
.flags
& (O_TRUNC
| O_CREAT
| O_TMPFILE
))
3857 op
.lookup_flags
|= LOOKUP_CACHED
;
3858 op
.open_flag
|= O_NONBLOCK
;
3861 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3865 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3868 * We could hang on to this 'fd' on retrying, but seems like
3869 * marginal gain for something that is now known to be a slower
3870 * path. So just put it, and we'll get a new one when we retry.
3874 ret
= PTR_ERR(file
);
3875 /* only retry if RESOLVE_CACHED wasn't already set by application */
3876 if (ret
== -EAGAIN
&&
3877 (!resolve_nonblock
&& (issue_flags
& IO_URING_F_NONBLOCK
)))
3882 if ((issue_flags
& IO_URING_F_NONBLOCK
) && !nonblock_set
)
3883 file
->f_flags
&= ~O_NONBLOCK
;
3884 fsnotify_open(file
);
3885 fd_install(ret
, file
);
3887 putname(req
->open
.filename
);
3888 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3891 __io_req_complete(req
, issue_flags
, ret
, 0);
3895 static int io_openat(struct io_kiocb
*req
, unsigned int issue_flags
)
3897 return io_openat2(req
, issue_flags
);
3900 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3901 const struct io_uring_sqe
*sqe
)
3903 struct io_provide_buf
*p
= &req
->pbuf
;
3906 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3909 tmp
= READ_ONCE(sqe
->fd
);
3910 if (!tmp
|| tmp
> USHRT_MAX
)
3913 memset(p
, 0, sizeof(*p
));
3915 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3919 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3920 int bgid
, unsigned nbufs
)
3924 /* shouldn't happen */
3928 /* the head kbuf is the list itself */
3929 while (!list_empty(&buf
->list
)) {
3930 struct io_buffer
*nxt
;
3932 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3933 list_del(&nxt
->list
);
3940 xa_erase(&ctx
->io_buffers
, bgid
);
3945 static int io_remove_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
3947 struct io_provide_buf
*p
= &req
->pbuf
;
3948 struct io_ring_ctx
*ctx
= req
->ctx
;
3949 struct io_buffer
*head
;
3951 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3953 io_ring_submit_lock(ctx
, !force_nonblock
);
3955 lockdep_assert_held(&ctx
->uring_lock
);
3958 head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
3960 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3964 /* complete before unlock, IOPOLL may need the lock */
3965 __io_req_complete(req
, issue_flags
, ret
, 0);
3966 io_ring_submit_unlock(ctx
, !force_nonblock
);
3970 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3971 const struct io_uring_sqe
*sqe
)
3973 unsigned long size
, tmp_check
;
3974 struct io_provide_buf
*p
= &req
->pbuf
;
3977 if (sqe
->ioprio
|| sqe
->rw_flags
)
3980 tmp
= READ_ONCE(sqe
->fd
);
3981 if (!tmp
|| tmp
> USHRT_MAX
)
3984 p
->addr
= READ_ONCE(sqe
->addr
);
3985 p
->len
= READ_ONCE(sqe
->len
);
3987 if (check_mul_overflow((unsigned long)p
->len
, (unsigned long)p
->nbufs
,
3990 if (check_add_overflow((unsigned long)p
->addr
, size
, &tmp_check
))
3993 size
= (unsigned long)p
->len
* p
->nbufs
;
3994 if (!access_ok(u64_to_user_ptr(p
->addr
), size
))
3997 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3998 tmp
= READ_ONCE(sqe
->off
);
3999 if (tmp
> USHRT_MAX
)
4005 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
4007 struct io_buffer
*buf
;
4008 u64 addr
= pbuf
->addr
;
4009 int i
, bid
= pbuf
->bid
;
4011 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
4012 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
4017 buf
->len
= min_t(__u32
, pbuf
->len
, MAX_RW_COUNT
);
4022 INIT_LIST_HEAD(&buf
->list
);
4025 list_add_tail(&buf
->list
, &(*head
)->list
);
4029 return i
? i
: -ENOMEM
;
4032 static int io_provide_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
4034 struct io_provide_buf
*p
= &req
->pbuf
;
4035 struct io_ring_ctx
*ctx
= req
->ctx
;
4036 struct io_buffer
*head
, *list
;
4038 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4040 io_ring_submit_lock(ctx
, !force_nonblock
);
4042 lockdep_assert_held(&ctx
->uring_lock
);
4044 list
= head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
4046 ret
= io_add_buffers(p
, &head
);
4047 if (ret
>= 0 && !list
) {
4048 ret
= xa_insert(&ctx
->io_buffers
, p
->bgid
, head
, GFP_KERNEL
);
4050 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4054 /* complete before unlock, IOPOLL may need the lock */
4055 __io_req_complete(req
, issue_flags
, ret
, 0);
4056 io_ring_submit_unlock(ctx
, !force_nonblock
);
4060 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4061 const struct io_uring_sqe
*sqe
)
4063 #if defined(CONFIG_EPOLL)
4064 if (sqe
->ioprio
|| sqe
->buf_index
)
4066 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4069 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4070 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4071 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4073 if (ep_op_has_event(req
->epoll
.op
)) {
4074 struct epoll_event __user
*ev
;
4076 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4077 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4087 static int io_epoll_ctl(struct io_kiocb
*req
, unsigned int issue_flags
)
4089 #if defined(CONFIG_EPOLL)
4090 struct io_epoll
*ie
= &req
->epoll
;
4092 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4094 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4095 if (force_nonblock
&& ret
== -EAGAIN
)
4100 __io_req_complete(req
, issue_flags
, ret
, 0);
4107 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4109 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4110 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4112 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4115 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4116 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4117 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4124 static int io_madvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4126 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4127 struct io_madvise
*ma
= &req
->madvise
;
4130 if (issue_flags
& IO_URING_F_NONBLOCK
)
4133 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4136 io_req_complete(req
, ret
);
4143 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4145 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4147 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4150 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4151 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4152 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4156 static int io_fadvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4158 struct io_fadvise
*fa
= &req
->fadvise
;
4161 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4162 switch (fa
->advice
) {
4163 case POSIX_FADV_NORMAL
:
4164 case POSIX_FADV_RANDOM
:
4165 case POSIX_FADV_SEQUENTIAL
:
4172 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4175 __io_req_complete(req
, issue_flags
, ret
, 0);
4179 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4181 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4183 if (sqe
->ioprio
|| sqe
->buf_index
)
4185 if (req
->flags
& REQ_F_FIXED_FILE
)
4188 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4189 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4190 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4191 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4192 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4197 static int io_statx(struct io_kiocb
*req
, unsigned int issue_flags
)
4199 struct io_statx
*ctx
= &req
->statx
;
4202 if (issue_flags
& IO_URING_F_NONBLOCK
)
4205 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4210 io_req_complete(req
, ret
);
4214 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4216 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4218 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4219 sqe
->rw_flags
|| sqe
->buf_index
)
4221 if (req
->flags
& REQ_F_FIXED_FILE
)
4224 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4228 static int io_close(struct io_kiocb
*req
, unsigned int issue_flags
)
4230 struct files_struct
*files
= current
->files
;
4231 struct io_close
*close
= &req
->close
;
4232 struct fdtable
*fdt
;
4233 struct file
*file
= NULL
;
4236 spin_lock(&files
->file_lock
);
4237 fdt
= files_fdtable(files
);
4238 if (close
->fd
>= fdt
->max_fds
) {
4239 spin_unlock(&files
->file_lock
);
4242 file
= fdt
->fd
[close
->fd
];
4243 if (!file
|| file
->f_op
== &io_uring_fops
) {
4244 spin_unlock(&files
->file_lock
);
4249 /* if the file has a flush method, be safe and punt to async */
4250 if (file
->f_op
->flush
&& (issue_flags
& IO_URING_F_NONBLOCK
)) {
4251 spin_unlock(&files
->file_lock
);
4255 ret
= __close_fd_get_file(close
->fd
, &file
);
4256 spin_unlock(&files
->file_lock
);
4263 /* No ->flush() or already async, safely close from here */
4264 ret
= filp_close(file
, current
->files
);
4270 __io_req_complete(req
, issue_flags
, ret
, 0);
4274 static int io_sfr_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4276 struct io_ring_ctx
*ctx
= req
->ctx
;
4278 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4280 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4283 req
->sync
.off
= READ_ONCE(sqe
->off
);
4284 req
->sync
.len
= READ_ONCE(sqe
->len
);
4285 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4289 static int io_sync_file_range(struct io_kiocb
*req
, unsigned int issue_flags
)
4293 /* sync_file_range always requires a blocking context */
4294 if (issue_flags
& IO_URING_F_NONBLOCK
)
4297 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4301 io_req_complete(req
, ret
);
4305 #if defined(CONFIG_NET)
4306 static int io_setup_async_msg(struct io_kiocb
*req
,
4307 struct io_async_msghdr
*kmsg
)
4309 struct io_async_msghdr
*async_msg
= req
->async_data
;
4313 if (io_alloc_async_data(req
)) {
4314 kfree(kmsg
->free_iov
);
4317 async_msg
= req
->async_data
;
4318 req
->flags
|= REQ_F_NEED_CLEANUP
;
4319 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4320 async_msg
->msg
.msg_name
= &async_msg
->addr
;
4321 /* if were using fast_iov, set it to the new one */
4322 if (!async_msg
->free_iov
)
4323 async_msg
->msg
.msg_iter
.iov
= async_msg
->fast_iov
;
4328 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4329 struct io_async_msghdr
*iomsg
)
4331 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4332 iomsg
->free_iov
= iomsg
->fast_iov
;
4333 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4334 req
->sr_msg
.msg_flags
, &iomsg
->free_iov
);
4337 static int io_sendmsg_prep_async(struct io_kiocb
*req
)
4341 ret
= io_sendmsg_copy_hdr(req
, req
->async_data
);
4343 req
->flags
|= REQ_F_NEED_CLEANUP
;
4347 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4349 struct io_sr_msg
*sr
= &req
->sr_msg
;
4351 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4354 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4355 sr
->len
= READ_ONCE(sqe
->len
);
4356 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
) | MSG_NOSIGNAL
;
4357 if (sr
->msg_flags
& MSG_DONTWAIT
)
4358 req
->flags
|= REQ_F_NOWAIT
;
4360 #ifdef CONFIG_COMPAT
4361 if (req
->ctx
->compat
)
4362 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4367 static int io_sendmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4369 struct io_async_msghdr iomsg
, *kmsg
;
4370 struct socket
*sock
;
4375 sock
= sock_from_file(req
->file
);
4376 if (unlikely(!sock
))
4379 kmsg
= req
->async_data
;
4381 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4387 flags
= req
->sr_msg
.msg_flags
;
4388 if (issue_flags
& IO_URING_F_NONBLOCK
)
4389 flags
|= MSG_DONTWAIT
;
4390 if (flags
& MSG_WAITALL
)
4391 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
4393 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4394 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4395 return io_setup_async_msg(req
, kmsg
);
4396 if (ret
== -ERESTARTSYS
)
4399 /* fast path, check for non-NULL to avoid function call */
4401 kfree(kmsg
->free_iov
);
4402 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4405 __io_req_complete(req
, issue_flags
, ret
, 0);
4409 static int io_send(struct io_kiocb
*req
, unsigned int issue_flags
)
4411 struct io_sr_msg
*sr
= &req
->sr_msg
;
4414 struct socket
*sock
;
4419 sock
= sock_from_file(req
->file
);
4420 if (unlikely(!sock
))
4423 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4427 msg
.msg_name
= NULL
;
4428 msg
.msg_control
= NULL
;
4429 msg
.msg_controllen
= 0;
4430 msg
.msg_namelen
= 0;
4432 flags
= req
->sr_msg
.msg_flags
;
4433 if (issue_flags
& IO_URING_F_NONBLOCK
)
4434 flags
|= MSG_DONTWAIT
;
4435 if (flags
& MSG_WAITALL
)
4436 min_ret
= iov_iter_count(&msg
.msg_iter
);
4438 msg
.msg_flags
= flags
;
4439 ret
= sock_sendmsg(sock
, &msg
);
4440 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4442 if (ret
== -ERESTARTSYS
)
4447 __io_req_complete(req
, issue_flags
, ret
, 0);
4451 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4452 struct io_async_msghdr
*iomsg
)
4454 struct io_sr_msg
*sr
= &req
->sr_msg
;
4455 struct iovec __user
*uiov
;
4459 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4460 &iomsg
->uaddr
, &uiov
, &iov_len
);
4464 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4467 if (copy_from_user(iomsg
->fast_iov
, uiov
, sizeof(*uiov
)))
4469 sr
->len
= iomsg
->fast_iov
[0].iov_len
;
4470 iomsg
->free_iov
= NULL
;
4472 iomsg
->free_iov
= iomsg
->fast_iov
;
4473 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4474 &iomsg
->free_iov
, &iomsg
->msg
.msg_iter
,
4483 #ifdef CONFIG_COMPAT
4484 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4485 struct io_async_msghdr
*iomsg
)
4487 struct io_sr_msg
*sr
= &req
->sr_msg
;
4488 struct compat_iovec __user
*uiov
;
4493 ret
= __get_compat_msghdr(&iomsg
->msg
, sr
->umsg_compat
, &iomsg
->uaddr
,
4498 uiov
= compat_ptr(ptr
);
4499 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4500 compat_ssize_t clen
;
4504 if (!access_ok(uiov
, sizeof(*uiov
)))
4506 if (__get_user(clen
, &uiov
->iov_len
))
4511 iomsg
->free_iov
= NULL
;
4513 iomsg
->free_iov
= iomsg
->fast_iov
;
4514 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4515 UIO_FASTIOV
, &iomsg
->free_iov
,
4516 &iomsg
->msg
.msg_iter
, true);
4525 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4526 struct io_async_msghdr
*iomsg
)
4528 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4530 #ifdef CONFIG_COMPAT
4531 if (req
->ctx
->compat
)
4532 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4535 return __io_recvmsg_copy_hdr(req
, iomsg
);
4538 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4541 struct io_sr_msg
*sr
= &req
->sr_msg
;
4542 struct io_buffer
*kbuf
;
4544 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4549 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4553 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4555 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4558 static int io_recvmsg_prep_async(struct io_kiocb
*req
)
4562 ret
= io_recvmsg_copy_hdr(req
, req
->async_data
);
4564 req
->flags
|= REQ_F_NEED_CLEANUP
;
4568 static int io_recvmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4570 struct io_sr_msg
*sr
= &req
->sr_msg
;
4572 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4575 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4576 sr
->len
= READ_ONCE(sqe
->len
);
4577 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4578 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
) | MSG_NOSIGNAL
;
4579 if (sr
->msg_flags
& MSG_DONTWAIT
)
4580 req
->flags
|= REQ_F_NOWAIT
;
4582 #ifdef CONFIG_COMPAT
4583 if (req
->ctx
->compat
)
4584 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4589 static int io_recvmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4591 struct io_async_msghdr iomsg
, *kmsg
;
4592 struct socket
*sock
;
4593 struct io_buffer
*kbuf
;
4596 int ret
, cflags
= 0;
4597 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4599 sock
= sock_from_file(req
->file
);
4600 if (unlikely(!sock
))
4603 kmsg
= req
->async_data
;
4605 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4611 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4612 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4614 return PTR_ERR(kbuf
);
4615 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4616 kmsg
->fast_iov
[0].iov_len
= req
->sr_msg
.len
;
4617 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->fast_iov
,
4618 1, req
->sr_msg
.len
);
4621 flags
= req
->sr_msg
.msg_flags
;
4623 flags
|= MSG_DONTWAIT
;
4624 if (flags
& MSG_WAITALL
)
4625 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
4627 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4628 kmsg
->uaddr
, flags
);
4629 if (force_nonblock
&& ret
== -EAGAIN
)
4630 return io_setup_async_msg(req
, kmsg
);
4631 if (ret
== -ERESTARTSYS
)
4634 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4635 cflags
= io_put_recv_kbuf(req
);
4636 /* fast path, check for non-NULL to avoid function call */
4638 kfree(kmsg
->free_iov
);
4639 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4640 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (kmsg
->msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
4642 __io_req_complete(req
, issue_flags
, ret
, cflags
);
4646 static int io_recv(struct io_kiocb
*req
, unsigned int issue_flags
)
4648 struct io_buffer
*kbuf
;
4649 struct io_sr_msg
*sr
= &req
->sr_msg
;
4651 void __user
*buf
= sr
->buf
;
4652 struct socket
*sock
;
4656 int ret
, cflags
= 0;
4657 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4659 sock
= sock_from_file(req
->file
);
4660 if (unlikely(!sock
))
4663 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4664 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4666 return PTR_ERR(kbuf
);
4667 buf
= u64_to_user_ptr(kbuf
->addr
);
4670 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4674 msg
.msg_name
= NULL
;
4675 msg
.msg_control
= NULL
;
4676 msg
.msg_controllen
= 0;
4677 msg
.msg_namelen
= 0;
4678 msg
.msg_iocb
= NULL
;
4681 flags
= req
->sr_msg
.msg_flags
;
4683 flags
|= MSG_DONTWAIT
;
4684 if (flags
& MSG_WAITALL
)
4685 min_ret
= iov_iter_count(&msg
.msg_iter
);
4687 ret
= sock_recvmsg(sock
, &msg
, flags
);
4688 if (force_nonblock
&& ret
== -EAGAIN
)
4690 if (ret
== -ERESTARTSYS
)
4693 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4694 cflags
= io_put_recv_kbuf(req
);
4695 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
4697 __io_req_complete(req
, issue_flags
, ret
, cflags
);
4701 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4703 struct io_accept
*accept
= &req
->accept
;
4705 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4707 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4710 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4711 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4712 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4713 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4717 static int io_accept(struct io_kiocb
*req
, unsigned int issue_flags
)
4719 struct io_accept
*accept
= &req
->accept
;
4720 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4721 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4724 if (req
->file
->f_flags
& O_NONBLOCK
)
4725 req
->flags
|= REQ_F_NOWAIT
;
4727 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4728 accept
->addr_len
, accept
->flags
,
4730 if (ret
== -EAGAIN
&& force_nonblock
)
4733 if (ret
== -ERESTARTSYS
)
4737 __io_req_complete(req
, issue_flags
, ret
, 0);
4741 static int io_connect_prep_async(struct io_kiocb
*req
)
4743 struct io_async_connect
*io
= req
->async_data
;
4744 struct io_connect
*conn
= &req
->connect
;
4746 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
, &io
->address
);
4749 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4751 struct io_connect
*conn
= &req
->connect
;
4753 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4755 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4758 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4759 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4763 static int io_connect(struct io_kiocb
*req
, unsigned int issue_flags
)
4765 struct io_async_connect __io
, *io
;
4766 unsigned file_flags
;
4768 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4770 if (req
->async_data
) {
4771 io
= req
->async_data
;
4773 ret
= move_addr_to_kernel(req
->connect
.addr
,
4774 req
->connect
.addr_len
,
4781 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4783 ret
= __sys_connect_file(req
->file
, &io
->address
,
4784 req
->connect
.addr_len
, file_flags
);
4785 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4786 if (req
->async_data
)
4788 if (io_alloc_async_data(req
)) {
4792 memcpy(req
->async_data
, &__io
, sizeof(__io
));
4795 if (ret
== -ERESTARTSYS
)
4800 __io_req_complete(req
, issue_flags
, ret
, 0);
4803 #else /* !CONFIG_NET */
4804 #define IO_NETOP_FN(op) \
4805 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
4807 return -EOPNOTSUPP; \
4810 #define IO_NETOP_PREP(op) \
4812 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
4814 return -EOPNOTSUPP; \
4817 #define IO_NETOP_PREP_ASYNC(op) \
4819 static int io_##op##_prep_async(struct io_kiocb *req) \
4821 return -EOPNOTSUPP; \
4824 IO_NETOP_PREP_ASYNC(sendmsg
);
4825 IO_NETOP_PREP_ASYNC(recvmsg
);
4826 IO_NETOP_PREP_ASYNC(connect
);
4827 IO_NETOP_PREP(accept
);
4830 #endif /* CONFIG_NET */
4832 struct io_poll_table
{
4833 struct poll_table_struct pt
;
4834 struct io_kiocb
*req
;
4839 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4840 __poll_t mask
, io_req_tw_func_t func
)
4842 /* for instances that support it check for an event match first: */
4843 if (mask
&& !(mask
& poll
->events
))
4846 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4848 list_del_init(&poll
->wait
.entry
);
4851 req
->io_task_work
.func
= func
;
4854 * If this fails, then the task is exiting. When a task exits, the
4855 * work gets canceled, so just cancel this request as well instead
4856 * of executing it. We can't safely execute it anyway, as we may not
4857 * have the needed state needed for it anyway.
4859 io_req_task_work_add(req
);
4863 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4864 __acquires(&req
->ctx
->completion_lock
)
4866 struct io_ring_ctx
*ctx
= req
->ctx
;
4868 if (unlikely(req
->task
->flags
& PF_EXITING
))
4869 WRITE_ONCE(poll
->canceled
, true);
4871 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4872 struct poll_table_struct pt
= { ._key
= poll
->events
};
4874 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4877 spin_lock_irq(&ctx
->completion_lock
);
4878 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4879 add_wait_queue(poll
->head
, &poll
->wait
);
4886 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
4888 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
4889 if (req
->opcode
== IORING_OP_POLL_ADD
)
4890 return req
->async_data
;
4891 return req
->apoll
->double_poll
;
4894 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
4896 if (req
->opcode
== IORING_OP_POLL_ADD
)
4898 return &req
->apoll
->poll
;
4901 static void io_poll_remove_double(struct io_kiocb
*req
)
4902 __must_hold(&req
->ctx
->completion_lock
)
4904 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
4906 lockdep_assert_held(&req
->ctx
->completion_lock
);
4908 if (poll
&& poll
->head
) {
4909 struct wait_queue_head
*head
= poll
->head
;
4911 spin_lock(&head
->lock
);
4912 list_del_init(&poll
->wait
.entry
);
4913 if (poll
->wait
.private)
4916 spin_unlock(&head
->lock
);
4920 static bool io_poll_complete(struct io_kiocb
*req
, __poll_t mask
)
4921 __must_hold(&req
->ctx
->completion_lock
)
4923 struct io_ring_ctx
*ctx
= req
->ctx
;
4924 unsigned flags
= IORING_CQE_F_MORE
;
4927 if (READ_ONCE(req
->poll
.canceled
)) {
4929 req
->poll
.events
|= EPOLLONESHOT
;
4931 error
= mangle_poll(mask
);
4933 if (req
->poll
.events
& EPOLLONESHOT
)
4935 if (!io_cqring_fill_event(ctx
, req
->user_data
, error
, flags
)) {
4936 io_poll_remove_waitqs(req
);
4937 req
->poll
.done
= true;
4940 if (flags
& IORING_CQE_F_MORE
)
4943 io_commit_cqring(ctx
);
4944 return !(flags
& IORING_CQE_F_MORE
);
4947 static void io_poll_task_func(struct io_kiocb
*req
)
4949 struct io_ring_ctx
*ctx
= req
->ctx
;
4950 struct io_kiocb
*nxt
;
4952 if (io_poll_rewait(req
, &req
->poll
)) {
4953 spin_unlock_irq(&ctx
->completion_lock
);
4957 done
= io_poll_complete(req
, req
->result
);
4959 hash_del(&req
->hash_node
);
4962 add_wait_queue(req
->poll
.head
, &req
->poll
.wait
);
4964 spin_unlock_irq(&ctx
->completion_lock
);
4965 io_cqring_ev_posted(ctx
);
4968 nxt
= io_put_req_find_next(req
);
4970 io_req_task_submit(nxt
);
4975 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4976 int sync
, void *key
)
4978 struct io_kiocb
*req
= wait
->private;
4979 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
4980 __poll_t mask
= key_to_poll(key
);
4982 /* for instances that support it check for an event match first: */
4983 if (mask
&& !(mask
& poll
->events
))
4985 if (!(poll
->events
& EPOLLONESHOT
))
4986 return poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
4988 list_del_init(&wait
->entry
);
4993 spin_lock(&poll
->head
->lock
);
4994 done
= list_empty(&poll
->wait
.entry
);
4996 list_del_init(&poll
->wait
.entry
);
4997 /* make sure double remove sees this as being gone */
4998 wait
->private = NULL
;
4999 spin_unlock(&poll
->head
->lock
);
5001 /* use wait func handler, so it matches the rq type */
5002 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5009 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
5010 wait_queue_func_t wake_func
)
5014 poll
->canceled
= false;
5015 #define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
5016 /* mask in events that we always want/need */
5017 poll
->events
= events
| IO_POLL_UNMASK
;
5018 INIT_LIST_HEAD(&poll
->wait
.entry
);
5019 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5022 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5023 struct wait_queue_head
*head
,
5024 struct io_poll_iocb
**poll_ptr
)
5026 struct io_kiocb
*req
= pt
->req
;
5029 * The file being polled uses multiple waitqueues for poll handling
5030 * (e.g. one for read, one for write). Setup a separate io_poll_iocb
5033 if (unlikely(pt
->nr_entries
)) {
5034 struct io_poll_iocb
*poll_one
= poll
;
5036 /* already have a 2nd entry, fail a third attempt */
5038 pt
->error
= -EINVAL
;
5042 * Can't handle multishot for double wait for now, turn it
5043 * into one-shot mode.
5045 if (!(poll_one
->events
& EPOLLONESHOT
))
5046 poll_one
->events
|= EPOLLONESHOT
;
5047 /* double add on the same waitqueue head, ignore */
5048 if (poll_one
->head
== head
)
5050 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5052 pt
->error
= -ENOMEM
;
5055 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5057 poll
->wait
.private = req
;
5064 if (poll
->events
& EPOLLEXCLUSIVE
)
5065 add_wait_queue_exclusive(head
, &poll
->wait
);
5067 add_wait_queue(head
, &poll
->wait
);
5070 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5071 struct poll_table_struct
*p
)
5073 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5074 struct async_poll
*apoll
= pt
->req
->apoll
;
5076 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5079 static void io_async_task_func(struct io_kiocb
*req
)
5081 struct async_poll
*apoll
= req
->apoll
;
5082 struct io_ring_ctx
*ctx
= req
->ctx
;
5084 trace_io_uring_task_run(req
->ctx
, req
, req
->opcode
, req
->user_data
);
5086 if (io_poll_rewait(req
, &apoll
->poll
)) {
5087 spin_unlock_irq(&ctx
->completion_lock
);
5091 hash_del(&req
->hash_node
);
5092 io_poll_remove_double(req
);
5093 spin_unlock_irq(&ctx
->completion_lock
);
5095 if (!READ_ONCE(apoll
->poll
.canceled
))
5096 io_req_task_submit(req
);
5098 io_req_complete_failed(req
, -ECANCELED
);
5101 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5104 struct io_kiocb
*req
= wait
->private;
5105 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5107 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5110 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5113 static void io_poll_req_insert(struct io_kiocb
*req
)
5115 struct io_ring_ctx
*ctx
= req
->ctx
;
5116 struct hlist_head
*list
;
5118 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5119 hlist_add_head(&req
->hash_node
, list
);
5122 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5123 struct io_poll_iocb
*poll
,
5124 struct io_poll_table
*ipt
, __poll_t mask
,
5125 wait_queue_func_t wake_func
)
5126 __acquires(&ctx
->completion_lock
)
5128 struct io_ring_ctx
*ctx
= req
->ctx
;
5129 bool cancel
= false;
5131 INIT_HLIST_NODE(&req
->hash_node
);
5132 io_init_poll_iocb(poll
, mask
, wake_func
);
5133 poll
->file
= req
->file
;
5134 poll
->wait
.private = req
;
5136 ipt
->pt
._key
= mask
;
5139 ipt
->nr_entries
= 0;
5141 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5142 if (unlikely(!ipt
->nr_entries
) && !ipt
->error
)
5143 ipt
->error
= -EINVAL
;
5145 spin_lock_irq(&ctx
->completion_lock
);
5147 io_poll_remove_double(req
);
5148 if (likely(poll
->head
)) {
5149 spin_lock(&poll
->head
->lock
);
5150 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5156 if ((mask
&& (poll
->events
& EPOLLONESHOT
)) || ipt
->error
)
5157 list_del_init(&poll
->wait
.entry
);
5159 WRITE_ONCE(poll
->canceled
, true);
5160 else if (!poll
->done
) /* actually waiting for an event */
5161 io_poll_req_insert(req
);
5162 spin_unlock(&poll
->head
->lock
);
5174 static int io_arm_poll_handler(struct io_kiocb
*req
)
5176 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5177 struct io_ring_ctx
*ctx
= req
->ctx
;
5178 struct async_poll
*apoll
;
5179 struct io_poll_table ipt
;
5180 __poll_t ret
, mask
= EPOLLONESHOT
| POLLERR
| POLLPRI
;
5183 if (!req
->file
|| !file_can_poll(req
->file
))
5184 return IO_APOLL_ABORTED
;
5185 if (req
->flags
& REQ_F_POLLED
)
5186 return IO_APOLL_ABORTED
;
5187 if (!def
->pollin
&& !def
->pollout
)
5188 return IO_APOLL_ABORTED
;
5192 mask
|= POLLIN
| POLLRDNORM
;
5194 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5195 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5196 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5200 mask
|= POLLOUT
| POLLWRNORM
;
5203 /* if we can't nonblock try, then no point in arming a poll handler */
5204 if (!io_file_supports_async(req
, rw
))
5205 return IO_APOLL_ABORTED
;
5207 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5208 if (unlikely(!apoll
))
5209 return IO_APOLL_ABORTED
;
5210 apoll
->double_poll
= NULL
;
5212 req
->flags
|= REQ_F_POLLED
;
5213 ipt
.pt
._qproc
= io_async_queue_proc
;
5215 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5217 if (ret
|| ipt
.error
) {
5218 io_poll_remove_double(req
);
5219 spin_unlock_irq(&ctx
->completion_lock
);
5221 return IO_APOLL_READY
;
5222 return IO_APOLL_ABORTED
;
5224 spin_unlock_irq(&ctx
->completion_lock
);
5225 trace_io_uring_poll_arm(ctx
, req
, req
->opcode
, req
->user_data
,
5226 mask
, apoll
->poll
.events
);
5230 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5231 struct io_poll_iocb
*poll
, bool do_cancel
)
5232 __must_hold(&req
->ctx
->completion_lock
)
5234 bool do_complete
= false;
5238 spin_lock(&poll
->head
->lock
);
5240 WRITE_ONCE(poll
->canceled
, true);
5241 if (!list_empty(&poll
->wait
.entry
)) {
5242 list_del_init(&poll
->wait
.entry
);
5245 spin_unlock(&poll
->head
->lock
);
5246 hash_del(&req
->hash_node
);
5250 static bool io_poll_remove_waitqs(struct io_kiocb
*req
)
5251 __must_hold(&req
->ctx
->completion_lock
)
5255 io_poll_remove_double(req
);
5256 do_complete
= __io_poll_remove_one(req
, io_poll_get_single(req
), true);
5258 if (req
->opcode
!= IORING_OP_POLL_ADD
&& do_complete
) {
5259 /* non-poll requests have submit ref still */
5265 static bool io_poll_remove_one(struct io_kiocb
*req
)
5266 __must_hold(&req
->ctx
->completion_lock
)
5270 do_complete
= io_poll_remove_waitqs(req
);
5272 io_cqring_fill_event(req
->ctx
, req
->user_data
, -ECANCELED
, 0);
5273 io_commit_cqring(req
->ctx
);
5275 io_put_req_deferred(req
, 1);
5282 * Returns true if we found and killed one or more poll requests
5284 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5287 struct hlist_node
*tmp
;
5288 struct io_kiocb
*req
;
5291 spin_lock_irq(&ctx
->completion_lock
);
5292 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5293 struct hlist_head
*list
;
5295 list
= &ctx
->cancel_hash
[i
];
5296 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5297 if (io_match_task(req
, tsk
, cancel_all
))
5298 posted
+= io_poll_remove_one(req
);
5301 spin_unlock_irq(&ctx
->completion_lock
);
5304 io_cqring_ev_posted(ctx
);
5309 static struct io_kiocb
*io_poll_find(struct io_ring_ctx
*ctx
, __u64 sqe_addr
,
5311 __must_hold(&ctx
->completion_lock
)
5313 struct hlist_head
*list
;
5314 struct io_kiocb
*req
;
5316 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5317 hlist_for_each_entry(req
, list
, hash_node
) {
5318 if (sqe_addr
!= req
->user_data
)
5320 if (poll_only
&& req
->opcode
!= IORING_OP_POLL_ADD
)
5327 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
,
5329 __must_hold(&ctx
->completion_lock
)
5331 struct io_kiocb
*req
;
5333 req
= io_poll_find(ctx
, sqe_addr
, poll_only
);
5336 if (io_poll_remove_one(req
))
5342 static __poll_t
io_poll_parse_events(const struct io_uring_sqe
*sqe
,
5347 events
= READ_ONCE(sqe
->poll32_events
);
5349 events
= swahw32(events
);
5351 if (!(flags
& IORING_POLL_ADD_MULTI
))
5352 events
|= EPOLLONESHOT
;
5353 return demangle_poll(events
) | (events
& (EPOLLEXCLUSIVE
|EPOLLONESHOT
));
5356 static int io_poll_update_prep(struct io_kiocb
*req
,
5357 const struct io_uring_sqe
*sqe
)
5359 struct io_poll_update
*upd
= &req
->poll_update
;
5362 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5364 if (sqe
->ioprio
|| sqe
->buf_index
)
5366 flags
= READ_ONCE(sqe
->len
);
5367 if (flags
& ~(IORING_POLL_UPDATE_EVENTS
| IORING_POLL_UPDATE_USER_DATA
|
5368 IORING_POLL_ADD_MULTI
))
5370 /* meaningless without update */
5371 if (flags
== IORING_POLL_ADD_MULTI
)
5374 upd
->old_user_data
= READ_ONCE(sqe
->addr
);
5375 upd
->update_events
= flags
& IORING_POLL_UPDATE_EVENTS
;
5376 upd
->update_user_data
= flags
& IORING_POLL_UPDATE_USER_DATA
;
5378 upd
->new_user_data
= READ_ONCE(sqe
->off
);
5379 if (!upd
->update_user_data
&& upd
->new_user_data
)
5381 if (upd
->update_events
)
5382 upd
->events
= io_poll_parse_events(sqe
, flags
);
5383 else if (sqe
->poll32_events
)
5389 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5392 struct io_kiocb
*req
= wait
->private;
5393 struct io_poll_iocb
*poll
= &req
->poll
;
5395 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5398 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5399 struct poll_table_struct
*p
)
5401 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5403 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5406 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5408 struct io_poll_iocb
*poll
= &req
->poll
;
5411 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5413 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
|| sqe
->addr
)
5415 flags
= READ_ONCE(sqe
->len
);
5416 if (flags
& ~IORING_POLL_ADD_MULTI
)
5419 poll
->events
= io_poll_parse_events(sqe
, flags
);
5423 static int io_poll_add(struct io_kiocb
*req
, unsigned int issue_flags
)
5425 struct io_poll_iocb
*poll
= &req
->poll
;
5426 struct io_ring_ctx
*ctx
= req
->ctx
;
5427 struct io_poll_table ipt
;
5430 ipt
.pt
._qproc
= io_poll_queue_proc
;
5432 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5435 if (mask
) { /* no async, we'd stolen it */
5437 io_poll_complete(req
, mask
);
5439 spin_unlock_irq(&ctx
->completion_lock
);
5442 io_cqring_ev_posted(ctx
);
5443 if (poll
->events
& EPOLLONESHOT
)
5449 static int io_poll_update(struct io_kiocb
*req
, unsigned int issue_flags
)
5451 struct io_ring_ctx
*ctx
= req
->ctx
;
5452 struct io_kiocb
*preq
;
5456 spin_lock_irq(&ctx
->completion_lock
);
5457 preq
= io_poll_find(ctx
, req
->poll_update
.old_user_data
, true);
5463 if (!req
->poll_update
.update_events
&& !req
->poll_update
.update_user_data
) {
5465 ret
= io_poll_remove_one(preq
) ? 0 : -EALREADY
;
5470 * Don't allow racy completion with singleshot, as we cannot safely
5471 * update those. For multishot, if we're racing with completion, just
5472 * let completion re-add it.
5474 completing
= !__io_poll_remove_one(preq
, &preq
->poll
, false);
5475 if (completing
&& (preq
->poll
.events
& EPOLLONESHOT
)) {
5479 /* we now have a detached poll request. reissue. */
5483 spin_unlock_irq(&ctx
->completion_lock
);
5485 io_req_complete(req
, ret
);
5488 /* only mask one event flags, keep behavior flags */
5489 if (req
->poll_update
.update_events
) {
5490 preq
->poll
.events
&= ~0xffff;
5491 preq
->poll
.events
|= req
->poll_update
.events
& 0xffff;
5492 preq
->poll
.events
|= IO_POLL_UNMASK
;
5494 if (req
->poll_update
.update_user_data
)
5495 preq
->user_data
= req
->poll_update
.new_user_data
;
5496 spin_unlock_irq(&ctx
->completion_lock
);
5498 /* complete update request, we're done with it */
5499 io_req_complete(req
, ret
);
5502 ret
= io_poll_add(preq
, issue_flags
);
5505 io_req_complete(preq
, ret
);
5511 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5513 struct io_timeout_data
*data
= container_of(timer
,
5514 struct io_timeout_data
, timer
);
5515 struct io_kiocb
*req
= data
->req
;
5516 struct io_ring_ctx
*ctx
= req
->ctx
;
5517 unsigned long flags
;
5519 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5520 list_del_init(&req
->timeout
.list
);
5521 atomic_set(&req
->ctx
->cq_timeouts
,
5522 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5524 io_cqring_fill_event(ctx
, req
->user_data
, -ETIME
, 0);
5525 io_commit_cqring(ctx
);
5526 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5528 io_cqring_ev_posted(ctx
);
5531 return HRTIMER_NORESTART
;
5534 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5536 __must_hold(&ctx
->completion_lock
)
5538 struct io_timeout_data
*io
;
5539 struct io_kiocb
*req
;
5542 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5543 found
= user_data
== req
->user_data
;
5548 return ERR_PTR(-ENOENT
);
5550 io
= req
->async_data
;
5551 if (hrtimer_try_to_cancel(&io
->timer
) == -1)
5552 return ERR_PTR(-EALREADY
);
5553 list_del_init(&req
->timeout
.list
);
5557 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5558 __must_hold(&ctx
->completion_lock
)
5560 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5563 return PTR_ERR(req
);
5566 io_cqring_fill_event(ctx
, req
->user_data
, -ECANCELED
, 0);
5567 io_put_req_deferred(req
, 1);
5571 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
5572 struct timespec64
*ts
, enum hrtimer_mode mode
)
5573 __must_hold(&ctx
->completion_lock
)
5575 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5576 struct io_timeout_data
*data
;
5579 return PTR_ERR(req
);
5581 req
->timeout
.off
= 0; /* noseq */
5582 data
= req
->async_data
;
5583 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
5584 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, mode
);
5585 data
->timer
.function
= io_timeout_fn
;
5586 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
5590 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5591 const struct io_uring_sqe
*sqe
)
5593 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5595 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5597 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5599 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5602 tr
->addr
= READ_ONCE(sqe
->addr
);
5603 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
5604 if (tr
->flags
& IORING_TIMEOUT_UPDATE
) {
5605 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE
|IORING_TIMEOUT_ABS
))
5607 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
5609 } else if (tr
->flags
) {
5610 /* timeout removal doesn't support flags */
5617 static inline enum hrtimer_mode
io_translate_timeout_mode(unsigned int flags
)
5619 return (flags
& IORING_TIMEOUT_ABS
) ? HRTIMER_MODE_ABS
5624 * Remove or update an existing timeout command
5626 static int io_timeout_remove(struct io_kiocb
*req
, unsigned int issue_flags
)
5628 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
5629 struct io_ring_ctx
*ctx
= req
->ctx
;
5632 spin_lock_irq(&ctx
->completion_lock
);
5633 if (!(req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
))
5634 ret
= io_timeout_cancel(ctx
, tr
->addr
);
5636 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
,
5637 io_translate_timeout_mode(tr
->flags
));
5639 io_cqring_fill_event(ctx
, req
->user_data
, ret
, 0);
5640 io_commit_cqring(ctx
);
5641 spin_unlock_irq(&ctx
->completion_lock
);
5642 io_cqring_ev_posted(ctx
);
5649 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5650 bool is_timeout_link
)
5652 struct io_timeout_data
*data
;
5654 u32 off
= READ_ONCE(sqe
->off
);
5656 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5658 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5660 if (off
&& is_timeout_link
)
5662 flags
= READ_ONCE(sqe
->timeout_flags
);
5663 if (flags
& ~IORING_TIMEOUT_ABS
)
5666 req
->timeout
.off
= off
;
5667 if (unlikely(off
&& !req
->ctx
->off_timeout_used
))
5668 req
->ctx
->off_timeout_used
= true;
5670 if (!req
->async_data
&& io_alloc_async_data(req
))
5673 data
= req
->async_data
;
5676 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5679 data
->mode
= io_translate_timeout_mode(flags
);
5680 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5681 if (is_timeout_link
)
5682 io_req_track_inflight(req
);
5686 static int io_timeout(struct io_kiocb
*req
, unsigned int issue_flags
)
5688 struct io_ring_ctx
*ctx
= req
->ctx
;
5689 struct io_timeout_data
*data
= req
->async_data
;
5690 struct list_head
*entry
;
5691 u32 tail
, off
= req
->timeout
.off
;
5693 spin_lock_irq(&ctx
->completion_lock
);
5696 * sqe->off holds how many events that need to occur for this
5697 * timeout event to be satisfied. If it isn't set, then this is
5698 * a pure timeout request, sequence isn't used.
5700 if (io_is_timeout_noseq(req
)) {
5701 entry
= ctx
->timeout_list
.prev
;
5705 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5706 req
->timeout
.target_seq
= tail
+ off
;
5708 /* Update the last seq here in case io_flush_timeouts() hasn't.
5709 * This is safe because ->completion_lock is held, and submissions
5710 * and completions are never mixed in the same ->completion_lock section.
5712 ctx
->cq_last_tm_flush
= tail
;
5715 * Insertion sort, ensuring the first entry in the list is always
5716 * the one we need first.
5718 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5719 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5722 if (io_is_timeout_noseq(nxt
))
5724 /* nxt.seq is behind @tail, otherwise would've been completed */
5725 if (off
>= nxt
->timeout
.target_seq
- tail
)
5729 list_add(&req
->timeout
.list
, entry
);
5730 data
->timer
.function
= io_timeout_fn
;
5731 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5732 spin_unlock_irq(&ctx
->completion_lock
);
5736 struct io_cancel_data
{
5737 struct io_ring_ctx
*ctx
;
5741 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5743 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5744 struct io_cancel_data
*cd
= data
;
5746 return req
->ctx
== cd
->ctx
&& req
->user_data
== cd
->user_data
;
5749 static int io_async_cancel_one(struct io_uring_task
*tctx
, u64 user_data
,
5750 struct io_ring_ctx
*ctx
)
5752 struct io_cancel_data data
= { .ctx
= ctx
, .user_data
= user_data
, };
5753 enum io_wq_cancel cancel_ret
;
5756 if (!tctx
|| !tctx
->io_wq
)
5759 cancel_ret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_cb
, &data
, false);
5760 switch (cancel_ret
) {
5761 case IO_WQ_CANCEL_OK
:
5764 case IO_WQ_CANCEL_RUNNING
:
5767 case IO_WQ_CANCEL_NOTFOUND
:
5775 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5776 struct io_kiocb
*req
, __u64 sqe_addr
,
5779 unsigned long flags
;
5782 ret
= io_async_cancel_one(req
->task
->io_uring
, sqe_addr
, ctx
);
5783 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5786 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5789 ret
= io_poll_cancel(ctx
, sqe_addr
, false);
5793 io_cqring_fill_event(ctx
, req
->user_data
, ret
, 0);
5794 io_commit_cqring(ctx
);
5795 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5796 io_cqring_ev_posted(ctx
);
5802 static int io_async_cancel_prep(struct io_kiocb
*req
,
5803 const struct io_uring_sqe
*sqe
)
5805 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5807 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5809 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5812 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5816 static int io_async_cancel(struct io_kiocb
*req
, unsigned int issue_flags
)
5818 struct io_ring_ctx
*ctx
= req
->ctx
;
5819 u64 sqe_addr
= req
->cancel
.addr
;
5820 struct io_tctx_node
*node
;
5823 /* tasks should wait for their io-wq threads, so safe w/o sync */
5824 ret
= io_async_cancel_one(req
->task
->io_uring
, sqe_addr
, ctx
);
5825 spin_lock_irq(&ctx
->completion_lock
);
5828 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5831 ret
= io_poll_cancel(ctx
, sqe_addr
, false);
5834 spin_unlock_irq(&ctx
->completion_lock
);
5836 /* slow path, try all io-wq's */
5837 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
5839 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
5840 struct io_uring_task
*tctx
= node
->task
->io_uring
;
5842 ret
= io_async_cancel_one(tctx
, req
->cancel
.addr
, ctx
);
5846 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
5848 spin_lock_irq(&ctx
->completion_lock
);
5850 io_cqring_fill_event(ctx
, req
->user_data
, ret
, 0);
5851 io_commit_cqring(ctx
);
5852 spin_unlock_irq(&ctx
->completion_lock
);
5853 io_cqring_ev_posted(ctx
);
5861 static int io_rsrc_update_prep(struct io_kiocb
*req
,
5862 const struct io_uring_sqe
*sqe
)
5864 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5866 if (sqe
->ioprio
|| sqe
->rw_flags
)
5869 req
->rsrc_update
.offset
= READ_ONCE(sqe
->off
);
5870 req
->rsrc_update
.nr_args
= READ_ONCE(sqe
->len
);
5871 if (!req
->rsrc_update
.nr_args
)
5873 req
->rsrc_update
.arg
= READ_ONCE(sqe
->addr
);
5877 static int io_files_update(struct io_kiocb
*req
, unsigned int issue_flags
)
5879 struct io_ring_ctx
*ctx
= req
->ctx
;
5880 struct io_uring_rsrc_update2 up
;
5883 if (issue_flags
& IO_URING_F_NONBLOCK
)
5886 up
.offset
= req
->rsrc_update
.offset
;
5887 up
.data
= req
->rsrc_update
.arg
;
5892 mutex_lock(&ctx
->uring_lock
);
5893 ret
= __io_register_rsrc_update(ctx
, IORING_RSRC_FILE
,
5894 &up
, req
->rsrc_update
.nr_args
);
5895 mutex_unlock(&ctx
->uring_lock
);
5899 __io_req_complete(req
, issue_flags
, ret
, 0);
5903 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5905 switch (req
->opcode
) {
5908 case IORING_OP_READV
:
5909 case IORING_OP_READ_FIXED
:
5910 case IORING_OP_READ
:
5911 return io_read_prep(req
, sqe
);
5912 case IORING_OP_WRITEV
:
5913 case IORING_OP_WRITE_FIXED
:
5914 case IORING_OP_WRITE
:
5915 return io_write_prep(req
, sqe
);
5916 case IORING_OP_POLL_ADD
:
5917 return io_poll_add_prep(req
, sqe
);
5918 case IORING_OP_POLL_REMOVE
:
5919 return io_poll_update_prep(req
, sqe
);
5920 case IORING_OP_FSYNC
:
5921 return io_fsync_prep(req
, sqe
);
5922 case IORING_OP_SYNC_FILE_RANGE
:
5923 return io_sfr_prep(req
, sqe
);
5924 case IORING_OP_SENDMSG
:
5925 case IORING_OP_SEND
:
5926 return io_sendmsg_prep(req
, sqe
);
5927 case IORING_OP_RECVMSG
:
5928 case IORING_OP_RECV
:
5929 return io_recvmsg_prep(req
, sqe
);
5930 case IORING_OP_CONNECT
:
5931 return io_connect_prep(req
, sqe
);
5932 case IORING_OP_TIMEOUT
:
5933 return io_timeout_prep(req
, sqe
, false);
5934 case IORING_OP_TIMEOUT_REMOVE
:
5935 return io_timeout_remove_prep(req
, sqe
);
5936 case IORING_OP_ASYNC_CANCEL
:
5937 return io_async_cancel_prep(req
, sqe
);
5938 case IORING_OP_LINK_TIMEOUT
:
5939 return io_timeout_prep(req
, sqe
, true);
5940 case IORING_OP_ACCEPT
:
5941 return io_accept_prep(req
, sqe
);
5942 case IORING_OP_FALLOCATE
:
5943 return io_fallocate_prep(req
, sqe
);
5944 case IORING_OP_OPENAT
:
5945 return io_openat_prep(req
, sqe
);
5946 case IORING_OP_CLOSE
:
5947 return io_close_prep(req
, sqe
);
5948 case IORING_OP_FILES_UPDATE
:
5949 return io_rsrc_update_prep(req
, sqe
);
5950 case IORING_OP_STATX
:
5951 return io_statx_prep(req
, sqe
);
5952 case IORING_OP_FADVISE
:
5953 return io_fadvise_prep(req
, sqe
);
5954 case IORING_OP_MADVISE
:
5955 return io_madvise_prep(req
, sqe
);
5956 case IORING_OP_OPENAT2
:
5957 return io_openat2_prep(req
, sqe
);
5958 case IORING_OP_EPOLL_CTL
:
5959 return io_epoll_ctl_prep(req
, sqe
);
5960 case IORING_OP_SPLICE
:
5961 return io_splice_prep(req
, sqe
);
5962 case IORING_OP_PROVIDE_BUFFERS
:
5963 return io_provide_buffers_prep(req
, sqe
);
5964 case IORING_OP_REMOVE_BUFFERS
:
5965 return io_remove_buffers_prep(req
, sqe
);
5967 return io_tee_prep(req
, sqe
);
5968 case IORING_OP_SHUTDOWN
:
5969 return io_shutdown_prep(req
, sqe
);
5970 case IORING_OP_RENAMEAT
:
5971 return io_renameat_prep(req
, sqe
);
5972 case IORING_OP_UNLINKAT
:
5973 return io_unlinkat_prep(req
, sqe
);
5976 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5981 static int io_req_prep_async(struct io_kiocb
*req
)
5983 if (!io_op_defs
[req
->opcode
].needs_async_setup
)
5985 if (WARN_ON_ONCE(req
->async_data
))
5987 if (io_alloc_async_data(req
))
5990 switch (req
->opcode
) {
5991 case IORING_OP_READV
:
5992 return io_rw_prep_async(req
, READ
);
5993 case IORING_OP_WRITEV
:
5994 return io_rw_prep_async(req
, WRITE
);
5995 case IORING_OP_SENDMSG
:
5996 return io_sendmsg_prep_async(req
);
5997 case IORING_OP_RECVMSG
:
5998 return io_recvmsg_prep_async(req
);
5999 case IORING_OP_CONNECT
:
6000 return io_connect_prep_async(req
);
6002 printk_once(KERN_WARNING
"io_uring: prep_async() bad opcode %d\n",
6007 static u32
io_get_sequence(struct io_kiocb
*req
)
6009 u32 seq
= req
->ctx
->cached_sq_head
;
6011 /* need original cached_sq_head, but it was increased for each req */
6012 io_for_each_link(req
, req
)
6017 static bool io_drain_req(struct io_kiocb
*req
)
6019 struct io_kiocb
*pos
;
6020 struct io_ring_ctx
*ctx
= req
->ctx
;
6021 struct io_defer_entry
*de
;
6026 * If we need to drain a request in the middle of a link, drain the
6027 * head request and the next request/link after the current link.
6028 * Considering sequential execution of links, IOSQE_IO_DRAIN will be
6029 * maintained for every request of our link.
6031 if (ctx
->drain_next
) {
6032 req
->flags
|= REQ_F_IO_DRAIN
;
6033 ctx
->drain_next
= false;
6035 /* not interested in head, start from the first linked */
6036 io_for_each_link(pos
, req
->link
) {
6037 if (pos
->flags
& REQ_F_IO_DRAIN
) {
6038 ctx
->drain_next
= true;
6039 req
->flags
|= REQ_F_IO_DRAIN
;
6044 /* Still need defer if there is pending req in defer list. */
6045 if (likely(list_empty_careful(&ctx
->defer_list
) &&
6046 !(req
->flags
& REQ_F_IO_DRAIN
))) {
6047 ctx
->drain_active
= false;
6051 seq
= io_get_sequence(req
);
6052 /* Still a chance to pass the sequence check */
6053 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
6056 ret
= io_req_prep_async(req
);
6059 io_prep_async_link(req
);
6060 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
6064 io_req_complete_failed(req
, ret
);
6068 spin_lock_irq(&ctx
->completion_lock
);
6069 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
6070 spin_unlock_irq(&ctx
->completion_lock
);
6072 io_queue_async_work(req
);
6076 trace_io_uring_defer(ctx
, req
, req
->user_data
);
6079 list_add_tail(&de
->list
, &ctx
->defer_list
);
6080 spin_unlock_irq(&ctx
->completion_lock
);
6084 static void io_clean_op(struct io_kiocb
*req
)
6086 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6087 switch (req
->opcode
) {
6088 case IORING_OP_READV
:
6089 case IORING_OP_READ_FIXED
:
6090 case IORING_OP_READ
:
6091 kfree((void *)(unsigned long)req
->rw
.addr
);
6093 case IORING_OP_RECVMSG
:
6094 case IORING_OP_RECV
:
6095 kfree(req
->sr_msg
.kbuf
);
6100 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6101 switch (req
->opcode
) {
6102 case IORING_OP_READV
:
6103 case IORING_OP_READ_FIXED
:
6104 case IORING_OP_READ
:
6105 case IORING_OP_WRITEV
:
6106 case IORING_OP_WRITE_FIXED
:
6107 case IORING_OP_WRITE
: {
6108 struct io_async_rw
*io
= req
->async_data
;
6110 kfree(io
->free_iovec
);
6113 case IORING_OP_RECVMSG
:
6114 case IORING_OP_SENDMSG
: {
6115 struct io_async_msghdr
*io
= req
->async_data
;
6117 kfree(io
->free_iov
);
6120 case IORING_OP_SPLICE
:
6122 if (!(req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
))
6123 io_put_file(req
->splice
.file_in
);
6125 case IORING_OP_OPENAT
:
6126 case IORING_OP_OPENAT2
:
6127 if (req
->open
.filename
)
6128 putname(req
->open
.filename
);
6130 case IORING_OP_RENAMEAT
:
6131 putname(req
->rename
.oldpath
);
6132 putname(req
->rename
.newpath
);
6134 case IORING_OP_UNLINKAT
:
6135 putname(req
->unlink
.filename
);
6139 if ((req
->flags
& REQ_F_POLLED
) && req
->apoll
) {
6140 kfree(req
->apoll
->double_poll
);
6144 if (req
->flags
& REQ_F_INFLIGHT
) {
6145 struct io_uring_task
*tctx
= req
->task
->io_uring
;
6147 atomic_dec(&tctx
->inflight_tracked
);
6149 if (req
->flags
& REQ_F_CREDS
)
6150 put_cred(req
->creds
);
6152 req
->flags
&= ~IO_REQ_CLEAN_FLAGS
;
6155 static int io_issue_sqe(struct io_kiocb
*req
, unsigned int issue_flags
)
6157 struct io_ring_ctx
*ctx
= req
->ctx
;
6158 const struct cred
*creds
= NULL
;
6161 if ((req
->flags
& REQ_F_CREDS
) && req
->creds
!= current_cred())
6162 creds
= override_creds(req
->creds
);
6164 switch (req
->opcode
) {
6166 ret
= io_nop(req
, issue_flags
);
6168 case IORING_OP_READV
:
6169 case IORING_OP_READ_FIXED
:
6170 case IORING_OP_READ
:
6171 ret
= io_read(req
, issue_flags
);
6173 case IORING_OP_WRITEV
:
6174 case IORING_OP_WRITE_FIXED
:
6175 case IORING_OP_WRITE
:
6176 ret
= io_write(req
, issue_flags
);
6178 case IORING_OP_FSYNC
:
6179 ret
= io_fsync(req
, issue_flags
);
6181 case IORING_OP_POLL_ADD
:
6182 ret
= io_poll_add(req
, issue_flags
);
6184 case IORING_OP_POLL_REMOVE
:
6185 ret
= io_poll_update(req
, issue_flags
);
6187 case IORING_OP_SYNC_FILE_RANGE
:
6188 ret
= io_sync_file_range(req
, issue_flags
);
6190 case IORING_OP_SENDMSG
:
6191 ret
= io_sendmsg(req
, issue_flags
);
6193 case IORING_OP_SEND
:
6194 ret
= io_send(req
, issue_flags
);
6196 case IORING_OP_RECVMSG
:
6197 ret
= io_recvmsg(req
, issue_flags
);
6199 case IORING_OP_RECV
:
6200 ret
= io_recv(req
, issue_flags
);
6202 case IORING_OP_TIMEOUT
:
6203 ret
= io_timeout(req
, issue_flags
);
6205 case IORING_OP_TIMEOUT_REMOVE
:
6206 ret
= io_timeout_remove(req
, issue_flags
);
6208 case IORING_OP_ACCEPT
:
6209 ret
= io_accept(req
, issue_flags
);
6211 case IORING_OP_CONNECT
:
6212 ret
= io_connect(req
, issue_flags
);
6214 case IORING_OP_ASYNC_CANCEL
:
6215 ret
= io_async_cancel(req
, issue_flags
);
6217 case IORING_OP_FALLOCATE
:
6218 ret
= io_fallocate(req
, issue_flags
);
6220 case IORING_OP_OPENAT
:
6221 ret
= io_openat(req
, issue_flags
);
6223 case IORING_OP_CLOSE
:
6224 ret
= io_close(req
, issue_flags
);
6226 case IORING_OP_FILES_UPDATE
:
6227 ret
= io_files_update(req
, issue_flags
);
6229 case IORING_OP_STATX
:
6230 ret
= io_statx(req
, issue_flags
);
6232 case IORING_OP_FADVISE
:
6233 ret
= io_fadvise(req
, issue_flags
);
6235 case IORING_OP_MADVISE
:
6236 ret
= io_madvise(req
, issue_flags
);
6238 case IORING_OP_OPENAT2
:
6239 ret
= io_openat2(req
, issue_flags
);
6241 case IORING_OP_EPOLL_CTL
:
6242 ret
= io_epoll_ctl(req
, issue_flags
);
6244 case IORING_OP_SPLICE
:
6245 ret
= io_splice(req
, issue_flags
);
6247 case IORING_OP_PROVIDE_BUFFERS
:
6248 ret
= io_provide_buffers(req
, issue_flags
);
6250 case IORING_OP_REMOVE_BUFFERS
:
6251 ret
= io_remove_buffers(req
, issue_flags
);
6254 ret
= io_tee(req
, issue_flags
);
6256 case IORING_OP_SHUTDOWN
:
6257 ret
= io_shutdown(req
, issue_flags
);
6259 case IORING_OP_RENAMEAT
:
6260 ret
= io_renameat(req
, issue_flags
);
6262 case IORING_OP_UNLINKAT
:
6263 ret
= io_unlinkat(req
, issue_flags
);
6271 revert_creds(creds
);
6274 /* If the op doesn't have a file, we're not polling for it */
6275 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
)
6276 io_iopoll_req_issued(req
);
6281 static void io_wq_submit_work(struct io_wq_work
*work
)
6283 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6284 struct io_kiocb
*timeout
;
6287 timeout
= io_prep_linked_timeout(req
);
6289 io_queue_linked_timeout(timeout
);
6291 if (work
->flags
& IO_WQ_WORK_CANCEL
)
6296 ret
= io_issue_sqe(req
, 0);
6298 * We can get EAGAIN for polled IO even though we're
6299 * forcing a sync submission from here, since we can't
6300 * wait for request slots on the block side.
6308 /* avoid locking problems by failing it from a clean context */
6310 /* io-wq is going to take one down */
6312 io_req_task_queue_fail(req
, ret
);
6316 #define FFS_ASYNC_READ 0x1UL
6317 #define FFS_ASYNC_WRITE 0x2UL
6319 #define FFS_ISREG 0x4UL
6321 #define FFS_ISREG 0x0UL
6323 #define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
6325 static inline struct io_fixed_file
*io_fixed_file_slot(struct io_file_table
*table
,
6328 struct io_fixed_file
*table_l2
;
6330 table_l2
= table
->files
[i
>> IORING_FILE_TABLE_SHIFT
];
6331 return &table_l2
[i
& IORING_FILE_TABLE_MASK
];
6334 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6337 struct io_fixed_file
*slot
= io_fixed_file_slot(&ctx
->file_table
, index
);
6339 return (struct file
*) (slot
->file_ptr
& FFS_MASK
);
6342 static void io_fixed_file_set(struct io_fixed_file
*file_slot
, struct file
*file
)
6344 unsigned long file_ptr
= (unsigned long) file
;
6346 if (__io_file_supports_async(file
, READ
))
6347 file_ptr
|= FFS_ASYNC_READ
;
6348 if (__io_file_supports_async(file
, WRITE
))
6349 file_ptr
|= FFS_ASYNC_WRITE
;
6350 if (S_ISREG(file_inode(file
)->i_mode
))
6351 file_ptr
|= FFS_ISREG
;
6352 file_slot
->file_ptr
= file_ptr
;
6355 static struct file
*io_file_get(struct io_submit_state
*state
,
6356 struct io_kiocb
*req
, int fd
, bool fixed
)
6358 struct io_ring_ctx
*ctx
= req
->ctx
;
6362 unsigned long file_ptr
;
6364 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6366 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6367 file_ptr
= io_fixed_file_slot(&ctx
->file_table
, fd
)->file_ptr
;
6368 file
= (struct file
*) (file_ptr
& FFS_MASK
);
6369 file_ptr
&= ~FFS_MASK
;
6370 /* mask in overlapping REQ_F and FFS bits */
6371 req
->flags
|= (file_ptr
<< REQ_F_ASYNC_READ_BIT
);
6372 io_req_set_rsrc_node(req
);
6374 trace_io_uring_file_get(ctx
, fd
);
6375 file
= __io_file_get(state
, fd
);
6377 /* we don't allow fixed io_uring files */
6378 if (file
&& unlikely(file
->f_op
== &io_uring_fops
))
6379 io_req_track_inflight(req
);
6385 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6387 struct io_timeout_data
*data
= container_of(timer
,
6388 struct io_timeout_data
, timer
);
6389 struct io_kiocb
*prev
, *req
= data
->req
;
6390 struct io_ring_ctx
*ctx
= req
->ctx
;
6391 unsigned long flags
;
6393 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6394 prev
= req
->timeout
.head
;
6395 req
->timeout
.head
= NULL
;
6398 * We don't expect the list to be empty, that will only happen if we
6399 * race with the completion of the linked work.
6402 io_remove_next_linked(prev
);
6403 if (!req_ref_inc_not_zero(prev
))
6406 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6409 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6410 io_put_req_deferred(prev
, 1);
6411 io_put_req_deferred(req
, 1);
6413 io_req_complete_post(req
, -ETIME
, 0);
6415 return HRTIMER_NORESTART
;
6418 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6420 struct io_ring_ctx
*ctx
= req
->ctx
;
6422 spin_lock_irq(&ctx
->completion_lock
);
6424 * If the back reference is NULL, then our linked request finished
6425 * before we got a chance to setup the timer
6427 if (req
->timeout
.head
) {
6428 struct io_timeout_data
*data
= req
->async_data
;
6430 data
->timer
.function
= io_link_timeout_fn
;
6431 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6434 spin_unlock_irq(&ctx
->completion_lock
);
6435 /* drop submission reference */
6439 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6441 struct io_kiocb
*nxt
= req
->link
;
6443 if (!nxt
|| (req
->flags
& REQ_F_LINK_TIMEOUT
) ||
6444 nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6447 nxt
->timeout
.head
= req
;
6448 nxt
->flags
|= REQ_F_LTIMEOUT_ACTIVE
;
6449 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6453 static void __io_queue_sqe(struct io_kiocb
*req
)
6455 struct io_kiocb
*linked_timeout
= io_prep_linked_timeout(req
);
6459 ret
= io_issue_sqe(req
, IO_URING_F_NONBLOCK
|IO_URING_F_COMPLETE_DEFER
);
6462 * We async punt it if the file wasn't marked NOWAIT, or if the file
6463 * doesn't support non-blocking read/write attempts
6466 /* drop submission reference */
6467 if (req
->flags
& REQ_F_COMPLETE_INLINE
) {
6468 struct io_ring_ctx
*ctx
= req
->ctx
;
6469 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
6471 cs
->reqs
[cs
->nr
++] = req
;
6472 if (cs
->nr
== ARRAY_SIZE(cs
->reqs
))
6473 io_submit_flush_completions(ctx
);
6477 } else if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6478 switch (io_arm_poll_handler(req
)) {
6479 case IO_APOLL_READY
:
6481 case IO_APOLL_ABORTED
:
6483 * Queued up for async execution, worker will release
6484 * submit reference when the iocb is actually submitted.
6486 io_queue_async_work(req
);
6490 io_req_complete_failed(req
, ret
);
6493 io_queue_linked_timeout(linked_timeout
);
6496 static inline void io_queue_sqe(struct io_kiocb
*req
)
6498 if (unlikely(req
->ctx
->drain_active
) && io_drain_req(req
))
6501 if (likely(!(req
->flags
& REQ_F_FORCE_ASYNC
))) {
6502 __io_queue_sqe(req
);
6504 int ret
= io_req_prep_async(req
);
6507 io_req_complete_failed(req
, ret
);
6509 io_queue_async_work(req
);
6514 * Check SQE restrictions (opcode and flags).
6516 * Returns 'true' if SQE is allowed, 'false' otherwise.
6518 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6519 struct io_kiocb
*req
,
6520 unsigned int sqe_flags
)
6522 if (likely(!ctx
->restricted
))
6525 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6528 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6529 ctx
->restrictions
.sqe_flags_required
)
6532 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6533 ctx
->restrictions
.sqe_flags_required
))
6539 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6540 const struct io_uring_sqe
*sqe
)
6542 struct io_submit_state
*state
;
6543 unsigned int sqe_flags
;
6544 int personality
, ret
= 0;
6546 req
->opcode
= READ_ONCE(sqe
->opcode
);
6547 /* same numerical values with corresponding REQ_F_*, safe to copy */
6548 req
->flags
= sqe_flags
= READ_ONCE(sqe
->flags
);
6549 req
->user_data
= READ_ONCE(sqe
->user_data
);
6551 req
->fixed_rsrc_refs
= NULL
;
6552 /* one is dropped after submission, the other at completion */
6553 atomic_set(&req
->refs
, 2);
6554 req
->task
= current
;
6556 /* enforce forwards compatibility on users */
6557 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6559 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6561 if (!io_check_restriction(ctx
, req
, sqe_flags
))
6564 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6565 !io_op_defs
[req
->opcode
].buffer_select
)
6567 if (unlikely(sqe_flags
& IOSQE_IO_DRAIN
))
6568 ctx
->drain_active
= true;
6570 personality
= READ_ONCE(sqe
->personality
);
6572 req
->creds
= xa_load(&ctx
->personalities
, personality
);
6575 get_cred(req
->creds
);
6576 req
->flags
|= REQ_F_CREDS
;
6578 state
= &ctx
->submit_state
;
6581 * Plug now if we have more than 1 IO left after this, and the target
6582 * is potentially a read/write to block based storage.
6584 if (!state
->plug_started
&& state
->ios_left
> 1 &&
6585 io_op_defs
[req
->opcode
].plug
) {
6586 blk_start_plug(&state
->plug
);
6587 state
->plug_started
= true;
6590 if (io_op_defs
[req
->opcode
].needs_file
) {
6591 bool fixed
= req
->flags
& REQ_F_FIXED_FILE
;
6593 req
->file
= io_file_get(state
, req
, READ_ONCE(sqe
->fd
), fixed
);
6594 if (unlikely(!req
->file
))
6602 static int io_submit_sqe(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6603 const struct io_uring_sqe
*sqe
)
6605 struct io_submit_link
*link
= &ctx
->submit_state
.link
;
6608 ret
= io_init_req(ctx
, req
, sqe
);
6609 if (unlikely(ret
)) {
6612 /* fail even hard links since we don't submit */
6613 req_set_fail(link
->head
);
6614 io_req_complete_failed(link
->head
, -ECANCELED
);
6617 io_req_complete_failed(req
, ret
);
6621 ret
= io_req_prep(req
, sqe
);
6625 /* don't need @sqe from now on */
6626 trace_io_uring_submit_sqe(ctx
, req
, req
->opcode
, req
->user_data
,
6628 ctx
->flags
& IORING_SETUP_SQPOLL
);
6631 * If we already have a head request, queue this one for async
6632 * submittal once the head completes. If we don't have a head but
6633 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6634 * submitted sync once the chain is complete. If none of those
6635 * conditions are true (normal request), then just queue it.
6638 struct io_kiocb
*head
= link
->head
;
6640 ret
= io_req_prep_async(req
);
6643 trace_io_uring_link(ctx
, req
, head
);
6644 link
->last
->link
= req
;
6647 /* last request of a link, enqueue the link */
6648 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6653 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6665 * Batched submission is done, ensure local IO is flushed out.
6667 static void io_submit_state_end(struct io_submit_state
*state
,
6668 struct io_ring_ctx
*ctx
)
6670 if (state
->link
.head
)
6671 io_queue_sqe(state
->link
.head
);
6673 io_submit_flush_completions(ctx
);
6674 if (state
->plug_started
)
6675 blk_finish_plug(&state
->plug
);
6676 io_state_file_put(state
);
6680 * Start submission side cache.
6682 static void io_submit_state_start(struct io_submit_state
*state
,
6683 unsigned int max_ios
)
6685 state
->plug_started
= false;
6686 state
->ios_left
= max_ios
;
6687 /* set only head, no need to init link_last in advance */
6688 state
->link
.head
= NULL
;
6691 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6693 struct io_rings
*rings
= ctx
->rings
;
6696 * Ensure any loads from the SQEs are done at this point,
6697 * since once we write the new head, the application could
6698 * write new data to them.
6700 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6704 * Fetch an sqe, if one is available. Note this returns a pointer to memory
6705 * that is mapped by userspace. This means that care needs to be taken to
6706 * ensure that reads are stable, as we cannot rely on userspace always
6707 * being a good citizen. If members of the sqe are validated and then later
6708 * used, it's important that those reads are done through READ_ONCE() to
6709 * prevent a re-load down the line.
6711 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6713 unsigned head
, mask
= ctx
->sq_entries
- 1;
6714 unsigned sq_idx
= ctx
->cached_sq_head
++ & mask
;
6717 * The cached sq head (or cq tail) serves two purposes:
6719 * 1) allows us to batch the cost of updating the user visible
6721 * 2) allows the kernel side to track the head on its own, even
6722 * though the application is the one updating it.
6724 head
= READ_ONCE(ctx
->sq_array
[sq_idx
]);
6725 if (likely(head
< ctx
->sq_entries
))
6726 return &ctx
->sq_sqes
[head
];
6728 /* drop invalid entries */
6730 WRITE_ONCE(ctx
->rings
->sq_dropped
,
6731 READ_ONCE(ctx
->rings
->sq_dropped
) + 1);
6735 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6737 struct io_uring_task
*tctx
;
6740 /* make sure SQ entry isn't read before tail */
6741 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6742 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6745 tctx
= current
->io_uring
;
6746 tctx
->cached_refs
-= nr
;
6747 if (unlikely(tctx
->cached_refs
< 0)) {
6748 unsigned int refill
= -tctx
->cached_refs
+ IO_TCTX_REFS_CACHE_NR
;
6750 percpu_counter_add(&tctx
->inflight
, refill
);
6751 refcount_add(refill
, ¤t
->usage
);
6752 tctx
->cached_refs
+= refill
;
6754 io_submit_state_start(&ctx
->submit_state
, nr
);
6756 while (submitted
< nr
) {
6757 const struct io_uring_sqe
*sqe
;
6758 struct io_kiocb
*req
;
6760 req
= io_alloc_req(ctx
);
6761 if (unlikely(!req
)) {
6763 submitted
= -EAGAIN
;
6766 sqe
= io_get_sqe(ctx
);
6767 if (unlikely(!sqe
)) {
6768 kmem_cache_free(req_cachep
, req
);
6771 /* will complete beyond this point, count as submitted */
6773 if (io_submit_sqe(ctx
, req
, sqe
))
6777 if (unlikely(submitted
!= nr
)) {
6778 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6779 int unused
= nr
- ref_used
;
6781 current
->io_uring
->cached_refs
+= unused
;
6782 percpu_ref_put_many(&ctx
->refs
, unused
);
6785 io_submit_state_end(&ctx
->submit_state
, ctx
);
6786 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6787 io_commit_sqring(ctx
);
6792 static inline bool io_sqd_events_pending(struct io_sq_data
*sqd
)
6794 return READ_ONCE(sqd
->state
);
6797 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6799 /* Tell userspace we may need a wakeup call */
6800 spin_lock_irq(&ctx
->completion_lock
);
6801 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6802 spin_unlock_irq(&ctx
->completion_lock
);
6805 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6807 spin_lock_irq(&ctx
->completion_lock
);
6808 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6809 spin_unlock_irq(&ctx
->completion_lock
);
6812 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
6814 unsigned int to_submit
;
6817 to_submit
= io_sqring_entries(ctx
);
6818 /* if we're handling multiple rings, cap submit size for fairness */
6819 if (cap_entries
&& to_submit
> IORING_SQPOLL_CAP_ENTRIES_VALUE
)
6820 to_submit
= IORING_SQPOLL_CAP_ENTRIES_VALUE
;
6822 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
6823 unsigned nr_events
= 0;
6824 const struct cred
*creds
= NULL
;
6826 if (ctx
->sq_creds
!= current_cred())
6827 creds
= override_creds(ctx
->sq_creds
);
6829 mutex_lock(&ctx
->uring_lock
);
6830 if (!list_empty(&ctx
->iopoll_list
))
6831 io_do_iopoll(ctx
, &nr_events
, 0, true);
6834 * Don't submit if refs are dying, good for io_uring_register(),
6835 * but also it is relied upon by io_ring_exit_work()
6837 if (to_submit
&& likely(!percpu_ref_is_dying(&ctx
->refs
)) &&
6838 !(ctx
->flags
& IORING_SETUP_R_DISABLED
))
6839 ret
= io_submit_sqes(ctx
, to_submit
);
6840 mutex_unlock(&ctx
->uring_lock
);
6842 if (to_submit
&& wq_has_sleeper(&ctx
->sqo_sq_wait
))
6843 wake_up(&ctx
->sqo_sq_wait
);
6845 revert_creds(creds
);
6851 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
6853 struct io_ring_ctx
*ctx
;
6854 unsigned sq_thread_idle
= 0;
6856 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6857 sq_thread_idle
= max(sq_thread_idle
, ctx
->sq_thread_idle
);
6858 sqd
->sq_thread_idle
= sq_thread_idle
;
6861 static bool io_sqd_handle_event(struct io_sq_data
*sqd
)
6863 bool did_sig
= false;
6864 struct ksignal ksig
;
6866 if (test_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
) ||
6867 signal_pending(current
)) {
6868 mutex_unlock(&sqd
->lock
);
6869 if (signal_pending(current
))
6870 did_sig
= get_signal(&ksig
);
6872 mutex_lock(&sqd
->lock
);
6874 return did_sig
|| test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
);
6877 static int io_sq_thread(void *data
)
6879 struct io_sq_data
*sqd
= data
;
6880 struct io_ring_ctx
*ctx
;
6881 unsigned long timeout
= 0;
6882 char buf
[TASK_COMM_LEN
];
6885 snprintf(buf
, sizeof(buf
), "iou-sqp-%d", sqd
->task_pid
);
6886 set_task_comm(current
, buf
);
6888 if (sqd
->sq_cpu
!= -1)
6889 set_cpus_allowed_ptr(current
, cpumask_of(sqd
->sq_cpu
));
6891 set_cpus_allowed_ptr(current
, cpu_online_mask
);
6892 current
->flags
|= PF_NO_SETAFFINITY
;
6894 mutex_lock(&sqd
->lock
);
6896 bool cap_entries
, sqt_spin
= false;
6898 if (io_sqd_events_pending(sqd
) || signal_pending(current
)) {
6899 if (io_sqd_handle_event(sqd
))
6901 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6904 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
6905 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6906 int ret
= __io_sq_thread(ctx
, cap_entries
);
6908 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
6911 if (io_run_task_work())
6914 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
6917 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6921 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
6922 if (!io_sqd_events_pending(sqd
) && !current
->task_works
) {
6923 bool needs_sched
= true;
6925 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6926 io_ring_set_wakeup_flag(ctx
);
6928 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6929 !list_empty_careful(&ctx
->iopoll_list
)) {
6930 needs_sched
= false;
6933 if (io_sqring_entries(ctx
)) {
6934 needs_sched
= false;
6940 mutex_unlock(&sqd
->lock
);
6942 mutex_lock(&sqd
->lock
);
6944 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6945 io_ring_clear_wakeup_flag(ctx
);
6948 finish_wait(&sqd
->wait
, &wait
);
6949 timeout
= jiffies
+ sqd
->sq_thread_idle
;
6952 io_uring_cancel_generic(true, sqd
);
6954 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6955 io_ring_set_wakeup_flag(ctx
);
6957 mutex_unlock(&sqd
->lock
);
6959 complete(&sqd
->exited
);
6963 struct io_wait_queue
{
6964 struct wait_queue_entry wq
;
6965 struct io_ring_ctx
*ctx
;
6967 unsigned nr_timeouts
;
6970 static inline bool io_should_wake(struct io_wait_queue
*iowq
)
6972 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6975 * Wake up if we have enough events, or if a timeout occurred since we
6976 * started waiting. For timeouts, we always want to return to userspace,
6977 * regardless of event count.
6979 return io_cqring_events(ctx
) >= iowq
->to_wait
||
6980 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6983 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6984 int wake_flags
, void *key
)
6986 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6990 * Cannot safely flush overflowed CQEs from here, ensure we wake up
6991 * the task, and the next invocation will do it.
6993 if (io_should_wake(iowq
) || test_bit(0, &iowq
->ctx
->check_cq_overflow
))
6994 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6998 static int io_run_task_work_sig(void)
7000 if (io_run_task_work())
7002 if (!signal_pending(current
))
7004 if (test_thread_flag(TIF_NOTIFY_SIGNAL
))
7005 return -ERESTARTSYS
;
7009 /* when returns >0, the caller should retry */
7010 static inline int io_cqring_wait_schedule(struct io_ring_ctx
*ctx
,
7011 struct io_wait_queue
*iowq
,
7012 signed long *timeout
)
7016 /* make sure we run task_work before checking for signals */
7017 ret
= io_run_task_work_sig();
7018 if (ret
|| io_should_wake(iowq
))
7020 /* let the caller flush overflows, retry */
7021 if (test_bit(0, &ctx
->check_cq_overflow
))
7024 *timeout
= schedule_timeout(*timeout
);
7025 return !*timeout
? -ETIME
: 1;
7029 * Wait until events become available, if we don't already have some. The
7030 * application must reap them itself, as they reside on the shared cq ring.
7032 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
7033 const sigset_t __user
*sig
, size_t sigsz
,
7034 struct __kernel_timespec __user
*uts
)
7036 struct io_wait_queue iowq
= {
7039 .func
= io_wake_function
,
7040 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
7043 .to_wait
= min_events
,
7045 struct io_rings
*rings
= ctx
->rings
;
7046 signed long timeout
= MAX_SCHEDULE_TIMEOUT
;
7050 io_cqring_overflow_flush(ctx
, false);
7051 if (io_cqring_events(ctx
) >= min_events
)
7053 if (!io_run_task_work())
7058 #ifdef CONFIG_COMPAT
7059 if (in_compat_syscall())
7060 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
7064 ret
= set_user_sigmask(sig
, sigsz
);
7071 struct timespec64 ts
;
7073 if (get_timespec64(&ts
, uts
))
7075 timeout
= timespec64_to_jiffies(&ts
);
7078 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
7079 trace_io_uring_cqring_wait(ctx
, min_events
);
7081 /* if we can't even flush overflow, don't wait for more */
7082 if (!io_cqring_overflow_flush(ctx
, false)) {
7086 prepare_to_wait_exclusive(&ctx
->cq_wait
, &iowq
.wq
,
7087 TASK_INTERRUPTIBLE
);
7088 ret
= io_cqring_wait_schedule(ctx
, &iowq
, &timeout
);
7089 finish_wait(&ctx
->cq_wait
, &iowq
.wq
);
7093 restore_saved_sigmask_unless(ret
== -EINTR
);
7095 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7098 static void io_free_page_table(void **table
, size_t size
)
7100 unsigned i
, nr_tables
= DIV_ROUND_UP(size
, PAGE_SIZE
);
7102 for (i
= 0; i
< nr_tables
; i
++)
7107 static void **io_alloc_page_table(size_t size
)
7109 unsigned i
, nr_tables
= DIV_ROUND_UP(size
, PAGE_SIZE
);
7110 size_t init_size
= size
;
7113 table
= kcalloc(nr_tables
, sizeof(*table
), GFP_KERNEL
);
7117 for (i
= 0; i
< nr_tables
; i
++) {
7118 unsigned int this_size
= min_t(size_t, size
, PAGE_SIZE
);
7120 table
[i
] = kzalloc(this_size
, GFP_KERNEL
);
7122 io_free_page_table(table
, init_size
);
7130 static inline void io_rsrc_ref_lock(struct io_ring_ctx
*ctx
)
7132 spin_lock_bh(&ctx
->rsrc_ref_lock
);
7135 static inline void io_rsrc_ref_unlock(struct io_ring_ctx
*ctx
)
7137 spin_unlock_bh(&ctx
->rsrc_ref_lock
);
7140 static void io_rsrc_node_destroy(struct io_rsrc_node
*ref_node
)
7142 percpu_ref_exit(&ref_node
->refs
);
7146 static void io_rsrc_node_switch(struct io_ring_ctx
*ctx
,
7147 struct io_rsrc_data
*data_to_kill
)
7149 WARN_ON_ONCE(!ctx
->rsrc_backup_node
);
7150 WARN_ON_ONCE(data_to_kill
&& !ctx
->rsrc_node
);
7153 struct io_rsrc_node
*rsrc_node
= ctx
->rsrc_node
;
7155 rsrc_node
->rsrc_data
= data_to_kill
;
7156 io_rsrc_ref_lock(ctx
);
7157 list_add_tail(&rsrc_node
->node
, &ctx
->rsrc_ref_list
);
7158 io_rsrc_ref_unlock(ctx
);
7160 atomic_inc(&data_to_kill
->refs
);
7161 percpu_ref_kill(&rsrc_node
->refs
);
7162 ctx
->rsrc_node
= NULL
;
7165 if (!ctx
->rsrc_node
) {
7166 ctx
->rsrc_node
= ctx
->rsrc_backup_node
;
7167 ctx
->rsrc_backup_node
= NULL
;
7171 static int io_rsrc_node_switch_start(struct io_ring_ctx
*ctx
)
7173 if (ctx
->rsrc_backup_node
)
7175 ctx
->rsrc_backup_node
= io_rsrc_node_alloc(ctx
);
7176 return ctx
->rsrc_backup_node
? 0 : -ENOMEM
;
7179 static int io_rsrc_ref_quiesce(struct io_rsrc_data
*data
, struct io_ring_ctx
*ctx
)
7183 /* As we may drop ->uring_lock, other task may have started quiesce */
7187 data
->quiesce
= true;
7189 ret
= io_rsrc_node_switch_start(ctx
);
7192 io_rsrc_node_switch(ctx
, data
);
7194 /* kill initial ref, already quiesced if zero */
7195 if (atomic_dec_and_test(&data
->refs
))
7197 flush_delayed_work(&ctx
->rsrc_put_work
);
7198 ret
= wait_for_completion_interruptible(&data
->done
);
7202 atomic_inc(&data
->refs
);
7203 /* wait for all works potentially completing data->done */
7204 flush_delayed_work(&ctx
->rsrc_put_work
);
7205 reinit_completion(&data
->done
);
7207 mutex_unlock(&ctx
->uring_lock
);
7208 ret
= io_run_task_work_sig();
7209 mutex_lock(&ctx
->uring_lock
);
7211 data
->quiesce
= false;
7216 static u64
*io_get_tag_slot(struct io_rsrc_data
*data
, unsigned int idx
)
7218 unsigned int off
= idx
& IO_RSRC_TAG_TABLE_MASK
;
7219 unsigned int table_idx
= idx
>> IO_RSRC_TAG_TABLE_SHIFT
;
7221 return &data
->tags
[table_idx
][off
];
7224 static void io_rsrc_data_free(struct io_rsrc_data
*data
)
7226 size_t size
= data
->nr
* sizeof(data
->tags
[0][0]);
7229 io_free_page_table((void **)data
->tags
, size
);
7233 static int io_rsrc_data_alloc(struct io_ring_ctx
*ctx
, rsrc_put_fn
*do_put
,
7234 u64 __user
*utags
, unsigned nr
,
7235 struct io_rsrc_data
**pdata
)
7237 struct io_rsrc_data
*data
;
7241 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
7244 data
->tags
= (u64
**)io_alloc_page_table(nr
* sizeof(data
->tags
[0][0]));
7252 data
->do_put
= do_put
;
7255 for (i
= 0; i
< nr
; i
++) {
7256 u64
*tag_slot
= io_get_tag_slot(data
, i
);
7258 if (copy_from_user(tag_slot
, &utags
[i
],
7264 atomic_set(&data
->refs
, 1);
7265 init_completion(&data
->done
);
7269 io_rsrc_data_free(data
);
7273 static bool io_alloc_file_tables(struct io_file_table
*table
, unsigned nr_files
)
7275 size_t size
= nr_files
* sizeof(struct io_fixed_file
);
7277 table
->files
= (struct io_fixed_file
**)io_alloc_page_table(size
);
7278 return !!table
->files
;
7281 static void io_free_file_tables(struct io_file_table
*table
, unsigned nr_files
)
7283 size_t size
= nr_files
* sizeof(struct io_fixed_file
);
7285 io_free_page_table((void **)table
->files
, size
);
7286 table
->files
= NULL
;
7289 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7291 #if defined(CONFIG_UNIX)
7292 if (ctx
->ring_sock
) {
7293 struct sock
*sock
= ctx
->ring_sock
->sk
;
7294 struct sk_buff
*skb
;
7296 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7302 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7305 file
= io_file_from_index(ctx
, i
);
7310 io_free_file_tables(&ctx
->file_table
, ctx
->nr_user_files
);
7311 io_rsrc_data_free(ctx
->file_data
);
7312 ctx
->file_data
= NULL
;
7313 ctx
->nr_user_files
= 0;
7316 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7320 if (!ctx
->file_data
)
7322 ret
= io_rsrc_ref_quiesce(ctx
->file_data
, ctx
);
7324 __io_sqe_files_unregister(ctx
);
7328 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7329 __releases(&sqd
->lock
)
7331 WARN_ON_ONCE(sqd
->thread
== current
);
7334 * Do the dance but not conditional clear_bit() because it'd race with
7335 * other threads incrementing park_pending and setting the bit.
7337 clear_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7338 if (atomic_dec_return(&sqd
->park_pending
))
7339 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7340 mutex_unlock(&sqd
->lock
);
7343 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7344 __acquires(&sqd
->lock
)
7346 WARN_ON_ONCE(sqd
->thread
== current
);
7348 atomic_inc(&sqd
->park_pending
);
7349 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7350 mutex_lock(&sqd
->lock
);
7352 wake_up_process(sqd
->thread
);
7355 static void io_sq_thread_stop(struct io_sq_data
*sqd
)
7357 WARN_ON_ONCE(sqd
->thread
== current
);
7358 WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
));
7360 set_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
);
7361 mutex_lock(&sqd
->lock
);
7363 wake_up_process(sqd
->thread
);
7364 mutex_unlock(&sqd
->lock
);
7365 wait_for_completion(&sqd
->exited
);
7368 static void io_put_sq_data(struct io_sq_data
*sqd
)
7370 if (refcount_dec_and_test(&sqd
->refs
)) {
7371 WARN_ON_ONCE(atomic_read(&sqd
->park_pending
));
7373 io_sq_thread_stop(sqd
);
7378 static void io_sq_thread_finish(struct io_ring_ctx
*ctx
)
7380 struct io_sq_data
*sqd
= ctx
->sq_data
;
7383 io_sq_thread_park(sqd
);
7384 list_del_init(&ctx
->sqd_list
);
7385 io_sqd_update_thread_idle(sqd
);
7386 io_sq_thread_unpark(sqd
);
7388 io_put_sq_data(sqd
);
7389 ctx
->sq_data
= NULL
;
7393 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7395 struct io_ring_ctx
*ctx_attach
;
7396 struct io_sq_data
*sqd
;
7399 f
= fdget(p
->wq_fd
);
7401 return ERR_PTR(-ENXIO
);
7402 if (f
.file
->f_op
!= &io_uring_fops
) {
7404 return ERR_PTR(-EINVAL
);
7407 ctx_attach
= f
.file
->private_data
;
7408 sqd
= ctx_attach
->sq_data
;
7411 return ERR_PTR(-EINVAL
);
7413 if (sqd
->task_tgid
!= current
->tgid
) {
7415 return ERR_PTR(-EPERM
);
7418 refcount_inc(&sqd
->refs
);
7423 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
,
7426 struct io_sq_data
*sqd
;
7429 if (p
->flags
& IORING_SETUP_ATTACH_WQ
) {
7430 sqd
= io_attach_sq_data(p
);
7435 /* fall through for EPERM case, setup new sqd/task */
7436 if (PTR_ERR(sqd
) != -EPERM
)
7440 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7442 return ERR_PTR(-ENOMEM
);
7444 atomic_set(&sqd
->park_pending
, 0);
7445 refcount_set(&sqd
->refs
, 1);
7446 INIT_LIST_HEAD(&sqd
->ctx_list
);
7447 mutex_init(&sqd
->lock
);
7448 init_waitqueue_head(&sqd
->wait
);
7449 init_completion(&sqd
->exited
);
7453 #if defined(CONFIG_UNIX)
7455 * Ensure the UNIX gc is aware of our file set, so we are certain that
7456 * the io_uring can be safely unregistered on process exit, even if we have
7457 * loops in the file referencing.
7459 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7461 struct sock
*sk
= ctx
->ring_sock
->sk
;
7462 struct scm_fp_list
*fpl
;
7463 struct sk_buff
*skb
;
7466 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7470 skb
= alloc_skb(0, GFP_KERNEL
);
7479 fpl
->user
= get_uid(current_user());
7480 for (i
= 0; i
< nr
; i
++) {
7481 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7485 fpl
->fp
[nr_files
] = get_file(file
);
7486 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7491 fpl
->max
= SCM_MAX_FD
;
7492 fpl
->count
= nr_files
;
7493 UNIXCB(skb
).fp
= fpl
;
7494 skb
->destructor
= unix_destruct_scm
;
7495 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7496 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7498 for (i
= 0; i
< nr_files
; i
++)
7509 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7510 * causes regular reference counting to break down. We rely on the UNIX
7511 * garbage collection to take care of this problem for us.
7513 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7515 unsigned left
, total
;
7519 left
= ctx
->nr_user_files
;
7521 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7523 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7527 total
+= this_files
;
7533 while (total
< ctx
->nr_user_files
) {
7534 struct file
*file
= io_file_from_index(ctx
, total
);
7544 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7550 static void io_rsrc_file_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
7552 struct file
*file
= prsrc
->file
;
7553 #if defined(CONFIG_UNIX)
7554 struct sock
*sock
= ctx
->ring_sock
->sk
;
7555 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7556 struct sk_buff
*skb
;
7559 __skb_queue_head_init(&list
);
7562 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7563 * remove this entry and rearrange the file array.
7565 skb
= skb_dequeue(head
);
7567 struct scm_fp_list
*fp
;
7569 fp
= UNIXCB(skb
).fp
;
7570 for (i
= 0; i
< fp
->count
; i
++) {
7573 if (fp
->fp
[i
] != file
)
7576 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7577 left
= fp
->count
- 1 - i
;
7579 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7580 left
* sizeof(struct file
*));
7587 __skb_queue_tail(&list
, skb
);
7597 __skb_queue_tail(&list
, skb
);
7599 skb
= skb_dequeue(head
);
7602 if (skb_peek(&list
)) {
7603 spin_lock_irq(&head
->lock
);
7604 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7605 __skb_queue_tail(head
, skb
);
7606 spin_unlock_irq(&head
->lock
);
7613 static void __io_rsrc_put_work(struct io_rsrc_node
*ref_node
)
7615 struct io_rsrc_data
*rsrc_data
= ref_node
->rsrc_data
;
7616 struct io_ring_ctx
*ctx
= rsrc_data
->ctx
;
7617 struct io_rsrc_put
*prsrc
, *tmp
;
7619 list_for_each_entry_safe(prsrc
, tmp
, &ref_node
->rsrc_list
, list
) {
7620 list_del(&prsrc
->list
);
7623 bool lock_ring
= ctx
->flags
& IORING_SETUP_IOPOLL
;
7625 io_ring_submit_lock(ctx
, lock_ring
);
7626 spin_lock_irq(&ctx
->completion_lock
);
7627 io_cqring_fill_event(ctx
, prsrc
->tag
, 0, 0);
7629 io_commit_cqring(ctx
);
7630 spin_unlock_irq(&ctx
->completion_lock
);
7631 io_cqring_ev_posted(ctx
);
7632 io_ring_submit_unlock(ctx
, lock_ring
);
7635 rsrc_data
->do_put(ctx
, prsrc
);
7639 io_rsrc_node_destroy(ref_node
);
7640 if (atomic_dec_and_test(&rsrc_data
->refs
))
7641 complete(&rsrc_data
->done
);
7644 static void io_rsrc_put_work(struct work_struct
*work
)
7646 struct io_ring_ctx
*ctx
;
7647 struct llist_node
*node
;
7649 ctx
= container_of(work
, struct io_ring_ctx
, rsrc_put_work
.work
);
7650 node
= llist_del_all(&ctx
->rsrc_put_llist
);
7653 struct io_rsrc_node
*ref_node
;
7654 struct llist_node
*next
= node
->next
;
7656 ref_node
= llist_entry(node
, struct io_rsrc_node
, llist
);
7657 __io_rsrc_put_work(ref_node
);
7662 static void io_rsrc_node_ref_zero(struct percpu_ref
*ref
)
7664 struct io_rsrc_node
*node
= container_of(ref
, struct io_rsrc_node
, refs
);
7665 struct io_ring_ctx
*ctx
= node
->rsrc_data
->ctx
;
7666 bool first_add
= false;
7668 io_rsrc_ref_lock(ctx
);
7671 while (!list_empty(&ctx
->rsrc_ref_list
)) {
7672 node
= list_first_entry(&ctx
->rsrc_ref_list
,
7673 struct io_rsrc_node
, node
);
7674 /* recycle ref nodes in order */
7677 list_del(&node
->node
);
7678 first_add
|= llist_add(&node
->llist
, &ctx
->rsrc_put_llist
);
7680 io_rsrc_ref_unlock(ctx
);
7683 mod_delayed_work(system_wq
, &ctx
->rsrc_put_work
, HZ
);
7686 static struct io_rsrc_node
*io_rsrc_node_alloc(struct io_ring_ctx
*ctx
)
7688 struct io_rsrc_node
*ref_node
;
7690 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7694 if (percpu_ref_init(&ref_node
->refs
, io_rsrc_node_ref_zero
,
7699 INIT_LIST_HEAD(&ref_node
->node
);
7700 INIT_LIST_HEAD(&ref_node
->rsrc_list
);
7701 ref_node
->done
= false;
7705 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7706 unsigned nr_args
, u64 __user
*tags
)
7708 __s32 __user
*fds
= (__s32 __user
*) arg
;
7717 if (nr_args
> IORING_MAX_FIXED_FILES
)
7719 ret
= io_rsrc_node_switch_start(ctx
);
7722 ret
= io_rsrc_data_alloc(ctx
, io_rsrc_file_put
, tags
, nr_args
,
7728 if (!io_alloc_file_tables(&ctx
->file_table
, nr_args
))
7731 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7732 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7736 /* allow sparse sets */
7739 if (unlikely(*io_get_tag_slot(ctx
->file_data
, i
)))
7746 if (unlikely(!file
))
7750 * Don't allow io_uring instances to be registered. If UNIX
7751 * isn't enabled, then this causes a reference cycle and this
7752 * instance can never get freed. If UNIX is enabled we'll
7753 * handle it just fine, but there's still no point in allowing
7754 * a ring fd as it doesn't support regular read/write anyway.
7756 if (file
->f_op
== &io_uring_fops
) {
7760 io_fixed_file_set(io_fixed_file_slot(&ctx
->file_table
, i
), file
);
7763 ret
= io_sqe_files_scm(ctx
);
7765 __io_sqe_files_unregister(ctx
);
7769 io_rsrc_node_switch(ctx
, NULL
);
7772 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7773 file
= io_file_from_index(ctx
, i
);
7777 io_free_file_tables(&ctx
->file_table
, nr_args
);
7778 ctx
->nr_user_files
= 0;
7780 io_rsrc_data_free(ctx
->file_data
);
7781 ctx
->file_data
= NULL
;
7785 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7788 #if defined(CONFIG_UNIX)
7789 struct sock
*sock
= ctx
->ring_sock
->sk
;
7790 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7791 struct sk_buff
*skb
;
7794 * See if we can merge this file into an existing skb SCM_RIGHTS
7795 * file set. If there's no room, fall back to allocating a new skb
7796 * and filling it in.
7798 spin_lock_irq(&head
->lock
);
7799 skb
= skb_peek(head
);
7801 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7803 if (fpl
->count
< SCM_MAX_FD
) {
7804 __skb_unlink(skb
, head
);
7805 spin_unlock_irq(&head
->lock
);
7806 fpl
->fp
[fpl
->count
] = get_file(file
);
7807 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7809 spin_lock_irq(&head
->lock
);
7810 __skb_queue_head(head
, skb
);
7815 spin_unlock_irq(&head
->lock
);
7822 return __io_sqe_files_scm(ctx
, 1, index
);
7828 static int io_queue_rsrc_removal(struct io_rsrc_data
*data
, unsigned idx
,
7829 struct io_rsrc_node
*node
, void *rsrc
)
7831 struct io_rsrc_put
*prsrc
;
7833 prsrc
= kzalloc(sizeof(*prsrc
), GFP_KERNEL
);
7837 prsrc
->tag
= *io_get_tag_slot(data
, idx
);
7839 list_add(&prsrc
->list
, &node
->rsrc_list
);
7843 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7844 struct io_uring_rsrc_update2
*up
,
7847 u64 __user
*tags
= u64_to_user_ptr(up
->tags
);
7848 __s32 __user
*fds
= u64_to_user_ptr(up
->data
);
7849 struct io_rsrc_data
*data
= ctx
->file_data
;
7850 struct io_fixed_file
*file_slot
;
7854 bool needs_switch
= false;
7856 if (!ctx
->file_data
)
7858 if (up
->offset
+ nr_args
> ctx
->nr_user_files
)
7861 for (done
= 0; done
< nr_args
; done
++) {
7864 if ((tags
&& copy_from_user(&tag
, &tags
[done
], sizeof(tag
))) ||
7865 copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7869 if ((fd
== IORING_REGISTER_FILES_SKIP
|| fd
== -1) && tag
) {
7873 if (fd
== IORING_REGISTER_FILES_SKIP
)
7876 i
= array_index_nospec(up
->offset
+ done
, ctx
->nr_user_files
);
7877 file_slot
= io_fixed_file_slot(&ctx
->file_table
, i
);
7879 if (file_slot
->file_ptr
) {
7880 file
= (struct file
*)(file_slot
->file_ptr
& FFS_MASK
);
7881 err
= io_queue_rsrc_removal(data
, up
->offset
+ done
,
7882 ctx
->rsrc_node
, file
);
7885 file_slot
->file_ptr
= 0;
7886 needs_switch
= true;
7895 * Don't allow io_uring instances to be registered. If
7896 * UNIX isn't enabled, then this causes a reference
7897 * cycle and this instance can never get freed. If UNIX
7898 * is enabled we'll handle it just fine, but there's
7899 * still no point in allowing a ring fd as it doesn't
7900 * support regular read/write anyway.
7902 if (file
->f_op
== &io_uring_fops
) {
7907 *io_get_tag_slot(data
, up
->offset
+ done
) = tag
;
7908 io_fixed_file_set(file_slot
, file
);
7909 err
= io_sqe_file_register(ctx
, file
, i
);
7911 file_slot
->file_ptr
= 0;
7919 io_rsrc_node_switch(ctx
, data
);
7920 return done
? done
: err
;
7923 static struct io_wq_work
*io_free_work(struct io_wq_work
*work
)
7925 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7927 req
= io_put_req_find_next(req
);
7928 return req
? &req
->work
: NULL
;
7931 static struct io_wq
*io_init_wq_offload(struct io_ring_ctx
*ctx
,
7932 struct task_struct
*task
)
7934 struct io_wq_hash
*hash
;
7935 struct io_wq_data data
;
7936 unsigned int concurrency
;
7938 mutex_lock(&ctx
->uring_lock
);
7939 hash
= ctx
->hash_map
;
7941 hash
= kzalloc(sizeof(*hash
), GFP_KERNEL
);
7943 mutex_unlock(&ctx
->uring_lock
);
7944 return ERR_PTR(-ENOMEM
);
7946 refcount_set(&hash
->refs
, 1);
7947 init_waitqueue_head(&hash
->wait
);
7948 ctx
->hash_map
= hash
;
7950 mutex_unlock(&ctx
->uring_lock
);
7954 data
.free_work
= io_free_work
;
7955 data
.do_work
= io_wq_submit_work
;
7957 /* Do QD, or 4 * CPUS, whatever is smallest */
7958 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7960 return io_wq_create(concurrency
, &data
);
7963 static int io_uring_alloc_task_context(struct task_struct
*task
,
7964 struct io_ring_ctx
*ctx
)
7966 struct io_uring_task
*tctx
;
7969 tctx
= kzalloc(sizeof(*tctx
), GFP_KERNEL
);
7970 if (unlikely(!tctx
))
7973 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
7974 if (unlikely(ret
)) {
7979 tctx
->io_wq
= io_init_wq_offload(ctx
, task
);
7980 if (IS_ERR(tctx
->io_wq
)) {
7981 ret
= PTR_ERR(tctx
->io_wq
);
7982 percpu_counter_destroy(&tctx
->inflight
);
7988 init_waitqueue_head(&tctx
->wait
);
7989 atomic_set(&tctx
->in_idle
, 0);
7990 atomic_set(&tctx
->inflight_tracked
, 0);
7991 task
->io_uring
= tctx
;
7992 spin_lock_init(&tctx
->task_lock
);
7993 INIT_WQ_LIST(&tctx
->task_list
);
7994 init_task_work(&tctx
->task_work
, tctx_task_work
);
7998 void __io_uring_free(struct task_struct
*tsk
)
8000 struct io_uring_task
*tctx
= tsk
->io_uring
;
8002 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
8003 WARN_ON_ONCE(tctx
->io_wq
);
8004 WARN_ON_ONCE(tctx
->cached_refs
);
8006 percpu_counter_destroy(&tctx
->inflight
);
8008 tsk
->io_uring
= NULL
;
8011 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
8012 struct io_uring_params
*p
)
8016 /* Retain compatibility with failing for an invalid attach attempt */
8017 if ((ctx
->flags
& (IORING_SETUP_ATTACH_WQ
| IORING_SETUP_SQPOLL
)) ==
8018 IORING_SETUP_ATTACH_WQ
) {
8021 f
= fdget(p
->wq_fd
);
8024 if (f
.file
->f_op
!= &io_uring_fops
) {
8030 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8031 struct task_struct
*tsk
;
8032 struct io_sq_data
*sqd
;
8035 sqd
= io_get_sq_data(p
, &attached
);
8041 ctx
->sq_creds
= get_current_cred();
8043 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
8044 if (!ctx
->sq_thread_idle
)
8045 ctx
->sq_thread_idle
= HZ
;
8047 io_sq_thread_park(sqd
);
8048 list_add(&ctx
->sqd_list
, &sqd
->ctx_list
);
8049 io_sqd_update_thread_idle(sqd
);
8050 /* don't attach to a dying SQPOLL thread, would be racy */
8051 ret
= (attached
&& !sqd
->thread
) ? -ENXIO
: 0;
8052 io_sq_thread_unpark(sqd
);
8059 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8060 int cpu
= p
->sq_thread_cpu
;
8063 if (cpu
>= nr_cpu_ids
|| !cpu_online(cpu
))
8070 sqd
->task_pid
= current
->pid
;
8071 sqd
->task_tgid
= current
->tgid
;
8072 tsk
= create_io_thread(io_sq_thread
, sqd
, NUMA_NO_NODE
);
8079 ret
= io_uring_alloc_task_context(tsk
, ctx
);
8080 wake_up_new_task(tsk
);
8083 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8084 /* Can't have SQ_AFF without SQPOLL */
8091 complete(&ctx
->sq_data
->exited
);
8093 io_sq_thread_finish(ctx
);
8097 static inline void __io_unaccount_mem(struct user_struct
*user
,
8098 unsigned long nr_pages
)
8100 atomic_long_sub(nr_pages
, &user
->locked_vm
);
8103 static inline int __io_account_mem(struct user_struct
*user
,
8104 unsigned long nr_pages
)
8106 unsigned long page_limit
, cur_pages
, new_pages
;
8108 /* Don't allow more pages than we can safely lock */
8109 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
8112 cur_pages
= atomic_long_read(&user
->locked_vm
);
8113 new_pages
= cur_pages
+ nr_pages
;
8114 if (new_pages
> page_limit
)
8116 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
8117 new_pages
) != cur_pages
);
8122 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8125 __io_unaccount_mem(ctx
->user
, nr_pages
);
8127 if (ctx
->mm_account
)
8128 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8131 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8136 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8141 if (ctx
->mm_account
)
8142 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8147 static void io_mem_free(void *ptr
)
8154 page
= virt_to_head_page(ptr
);
8155 if (put_page_testzero(page
))
8156 free_compound_page(page
);
8159 static void *io_mem_alloc(size_t size
)
8161 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8162 __GFP_NORETRY
| __GFP_ACCOUNT
;
8164 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8167 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8170 struct io_rings
*rings
;
8171 size_t off
, sq_array_size
;
8173 off
= struct_size(rings
, cqes
, cq_entries
);
8174 if (off
== SIZE_MAX
)
8178 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8186 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8187 if (sq_array_size
== SIZE_MAX
)
8190 if (check_add_overflow(off
, sq_array_size
, &off
))
8196 static void io_buffer_unmap(struct io_ring_ctx
*ctx
, struct io_mapped_ubuf
**slot
)
8198 struct io_mapped_ubuf
*imu
= *slot
;
8201 if (imu
!= ctx
->dummy_ubuf
) {
8202 for (i
= 0; i
< imu
->nr_bvecs
; i
++)
8203 unpin_user_page(imu
->bvec
[i
].bv_page
);
8204 if (imu
->acct_pages
)
8205 io_unaccount_mem(ctx
, imu
->acct_pages
);
8211 static void io_rsrc_buf_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
8213 io_buffer_unmap(ctx
, &prsrc
->buf
);
8217 static void __io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8221 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++)
8222 io_buffer_unmap(ctx
, &ctx
->user_bufs
[i
]);
8223 kfree(ctx
->user_bufs
);
8224 io_rsrc_data_free(ctx
->buf_data
);
8225 ctx
->user_bufs
= NULL
;
8226 ctx
->buf_data
= NULL
;
8227 ctx
->nr_user_bufs
= 0;
8230 static int io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8237 ret
= io_rsrc_ref_quiesce(ctx
->buf_data
, ctx
);
8239 __io_sqe_buffers_unregister(ctx
);
8243 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8244 void __user
*arg
, unsigned index
)
8246 struct iovec __user
*src
;
8248 #ifdef CONFIG_COMPAT
8250 struct compat_iovec __user
*ciovs
;
8251 struct compat_iovec ciov
;
8253 ciovs
= (struct compat_iovec __user
*) arg
;
8254 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8257 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8258 dst
->iov_len
= ciov
.iov_len
;
8262 src
= (struct iovec __user
*) arg
;
8263 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8269 * Not super efficient, but this is just a registration time. And we do cache
8270 * the last compound head, so generally we'll only do a full search if we don't
8273 * We check if the given compound head page has already been accounted, to
8274 * avoid double accounting it. This allows us to account the full size of the
8275 * page, not just the constituent pages of a huge page.
8277 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8278 int nr_pages
, struct page
*hpage
)
8282 /* check current page array */
8283 for (i
= 0; i
< nr_pages
; i
++) {
8284 if (!PageCompound(pages
[i
]))
8286 if (compound_head(pages
[i
]) == hpage
)
8290 /* check previously registered pages */
8291 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8292 struct io_mapped_ubuf
*imu
= ctx
->user_bufs
[i
];
8294 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8295 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8297 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8305 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8306 int nr_pages
, struct io_mapped_ubuf
*imu
,
8307 struct page
**last_hpage
)
8311 imu
->acct_pages
= 0;
8312 for (i
= 0; i
< nr_pages
; i
++) {
8313 if (!PageCompound(pages
[i
])) {
8318 hpage
= compound_head(pages
[i
]);
8319 if (hpage
== *last_hpage
)
8321 *last_hpage
= hpage
;
8322 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8324 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8328 if (!imu
->acct_pages
)
8331 ret
= io_account_mem(ctx
, imu
->acct_pages
);
8333 imu
->acct_pages
= 0;
8337 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, struct iovec
*iov
,
8338 struct io_mapped_ubuf
**pimu
,
8339 struct page
**last_hpage
)
8341 struct io_mapped_ubuf
*imu
= NULL
;
8342 struct vm_area_struct
**vmas
= NULL
;
8343 struct page
**pages
= NULL
;
8344 unsigned long off
, start
, end
, ubuf
;
8346 int ret
, pret
, nr_pages
, i
;
8348 if (!iov
->iov_base
) {
8349 *pimu
= ctx
->dummy_ubuf
;
8353 ubuf
= (unsigned long) iov
->iov_base
;
8354 end
= (ubuf
+ iov
->iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8355 start
= ubuf
>> PAGE_SHIFT
;
8356 nr_pages
= end
- start
;
8361 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*), GFP_KERNEL
);
8365 vmas
= kvmalloc_array(nr_pages
, sizeof(struct vm_area_struct
*),
8370 imu
= kvmalloc(struct_size(imu
, bvec
, nr_pages
), GFP_KERNEL
);
8375 mmap_read_lock(current
->mm
);
8376 pret
= pin_user_pages(ubuf
, nr_pages
, FOLL_WRITE
| FOLL_LONGTERM
,
8378 if (pret
== nr_pages
) {
8379 /* don't support file backed memory */
8380 for (i
= 0; i
< nr_pages
; i
++) {
8381 struct vm_area_struct
*vma
= vmas
[i
];
8383 if (vma_is_shmem(vma
))
8386 !is_file_hugepages(vma
->vm_file
)) {
8392 ret
= pret
< 0 ? pret
: -EFAULT
;
8394 mmap_read_unlock(current
->mm
);
8397 * if we did partial map, or found file backed vmas,
8398 * release any pages we did get
8401 unpin_user_pages(pages
, pret
);
8405 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, last_hpage
);
8407 unpin_user_pages(pages
, pret
);
8411 off
= ubuf
& ~PAGE_MASK
;
8412 size
= iov
->iov_len
;
8413 for (i
= 0; i
< nr_pages
; i
++) {
8416 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8417 imu
->bvec
[i
].bv_page
= pages
[i
];
8418 imu
->bvec
[i
].bv_len
= vec_len
;
8419 imu
->bvec
[i
].bv_offset
= off
;
8423 /* store original address for later verification */
8425 imu
->ubuf_end
= ubuf
+ iov
->iov_len
;
8426 imu
->nr_bvecs
= nr_pages
;
8437 static int io_buffers_map_alloc(struct io_ring_ctx
*ctx
, unsigned int nr_args
)
8439 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(*ctx
->user_bufs
), GFP_KERNEL
);
8440 return ctx
->user_bufs
? 0 : -ENOMEM
;
8443 static int io_buffer_validate(struct iovec
*iov
)
8445 unsigned long tmp
, acct_len
= iov
->iov_len
+ (PAGE_SIZE
- 1);
8448 * Don't impose further limits on the size and buffer
8449 * constraints here, we'll -EINVAL later when IO is
8450 * submitted if they are wrong.
8453 return iov
->iov_len
? -EFAULT
: 0;
8457 /* arbitrary limit, but we need something */
8458 if (iov
->iov_len
> SZ_1G
)
8461 if (check_add_overflow((unsigned long)iov
->iov_base
, acct_len
, &tmp
))
8467 static int io_sqe_buffers_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8468 unsigned int nr_args
, u64 __user
*tags
)
8470 struct page
*last_hpage
= NULL
;
8471 struct io_rsrc_data
*data
;
8477 if (!nr_args
|| nr_args
> IORING_MAX_REG_BUFFERS
)
8479 ret
= io_rsrc_node_switch_start(ctx
);
8482 ret
= io_rsrc_data_alloc(ctx
, io_rsrc_buf_put
, tags
, nr_args
, &data
);
8485 ret
= io_buffers_map_alloc(ctx
, nr_args
);
8487 io_rsrc_data_free(data
);
8491 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_bufs
++) {
8492 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8495 ret
= io_buffer_validate(&iov
);
8498 if (!iov
.iov_base
&& *io_get_tag_slot(data
, i
)) {
8503 ret
= io_sqe_buffer_register(ctx
, &iov
, &ctx
->user_bufs
[i
],
8509 WARN_ON_ONCE(ctx
->buf_data
);
8511 ctx
->buf_data
= data
;
8513 __io_sqe_buffers_unregister(ctx
);
8515 io_rsrc_node_switch(ctx
, NULL
);
8519 static int __io_sqe_buffers_update(struct io_ring_ctx
*ctx
,
8520 struct io_uring_rsrc_update2
*up
,
8521 unsigned int nr_args
)
8523 u64 __user
*tags
= u64_to_user_ptr(up
->tags
);
8524 struct iovec iov
, __user
*iovs
= u64_to_user_ptr(up
->data
);
8525 struct page
*last_hpage
= NULL
;
8526 bool needs_switch
= false;
8532 if (up
->offset
+ nr_args
> ctx
->nr_user_bufs
)
8535 for (done
= 0; done
< nr_args
; done
++) {
8536 struct io_mapped_ubuf
*imu
;
8537 int offset
= up
->offset
+ done
;
8540 err
= io_copy_iov(ctx
, &iov
, iovs
, done
);
8543 if (tags
&& copy_from_user(&tag
, &tags
[done
], sizeof(tag
))) {
8547 err
= io_buffer_validate(&iov
);
8550 if (!iov
.iov_base
&& tag
) {
8554 err
= io_sqe_buffer_register(ctx
, &iov
, &imu
, &last_hpage
);
8558 i
= array_index_nospec(offset
, ctx
->nr_user_bufs
);
8559 if (ctx
->user_bufs
[i
] != ctx
->dummy_ubuf
) {
8560 err
= io_queue_rsrc_removal(ctx
->buf_data
, offset
,
8561 ctx
->rsrc_node
, ctx
->user_bufs
[i
]);
8562 if (unlikely(err
)) {
8563 io_buffer_unmap(ctx
, &imu
);
8566 ctx
->user_bufs
[i
] = NULL
;
8567 needs_switch
= true;
8570 ctx
->user_bufs
[i
] = imu
;
8571 *io_get_tag_slot(ctx
->buf_data
, offset
) = tag
;
8575 io_rsrc_node_switch(ctx
, ctx
->buf_data
);
8576 return done
? done
: err
;
8579 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8581 __s32 __user
*fds
= arg
;
8587 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8590 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8591 if (IS_ERR(ctx
->cq_ev_fd
)) {
8592 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8594 ctx
->cq_ev_fd
= NULL
;
8601 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8603 if (ctx
->cq_ev_fd
) {
8604 eventfd_ctx_put(ctx
->cq_ev_fd
);
8605 ctx
->cq_ev_fd
= NULL
;
8612 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8614 struct io_buffer
*buf
;
8615 unsigned long index
;
8617 xa_for_each(&ctx
->io_buffers
, index
, buf
)
8618 __io_remove_buffers(ctx
, buf
, index
, -1U);
8621 static void io_req_cache_free(struct list_head
*list
, struct task_struct
*tsk
)
8623 struct io_kiocb
*req
, *nxt
;
8625 list_for_each_entry_safe(req
, nxt
, list
, compl.list
) {
8626 if (tsk
&& req
->task
!= tsk
)
8628 list_del(&req
->compl.list
);
8629 kmem_cache_free(req_cachep
, req
);
8633 static void io_req_caches_free(struct io_ring_ctx
*ctx
)
8635 struct io_submit_state
*submit_state
= &ctx
->submit_state
;
8636 struct io_comp_state
*cs
= &ctx
->submit_state
.comp
;
8638 mutex_lock(&ctx
->uring_lock
);
8640 if (submit_state
->free_reqs
) {
8641 kmem_cache_free_bulk(req_cachep
, submit_state
->free_reqs
,
8642 submit_state
->reqs
);
8643 submit_state
->free_reqs
= 0;
8646 io_flush_cached_locked_reqs(ctx
, cs
);
8647 io_req_cache_free(&cs
->free_list
, NULL
);
8648 mutex_unlock(&ctx
->uring_lock
);
8651 static bool io_wait_rsrc_data(struct io_rsrc_data
*data
)
8655 if (!atomic_dec_and_test(&data
->refs
))
8656 wait_for_completion(&data
->done
);
8660 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8662 io_sq_thread_finish(ctx
);
8664 if (ctx
->mm_account
) {
8665 mmdrop(ctx
->mm_account
);
8666 ctx
->mm_account
= NULL
;
8669 mutex_lock(&ctx
->uring_lock
);
8670 if (io_wait_rsrc_data(ctx
->buf_data
))
8671 __io_sqe_buffers_unregister(ctx
);
8672 if (io_wait_rsrc_data(ctx
->file_data
))
8673 __io_sqe_files_unregister(ctx
);
8675 __io_cqring_overflow_flush(ctx
, true);
8676 mutex_unlock(&ctx
->uring_lock
);
8677 io_eventfd_unregister(ctx
);
8678 io_destroy_buffers(ctx
);
8680 put_cred(ctx
->sq_creds
);
8682 /* there are no registered resources left, nobody uses it */
8684 io_rsrc_node_destroy(ctx
->rsrc_node
);
8685 if (ctx
->rsrc_backup_node
)
8686 io_rsrc_node_destroy(ctx
->rsrc_backup_node
);
8687 flush_delayed_work(&ctx
->rsrc_put_work
);
8689 WARN_ON_ONCE(!list_empty(&ctx
->rsrc_ref_list
));
8690 WARN_ON_ONCE(!llist_empty(&ctx
->rsrc_put_llist
));
8692 #if defined(CONFIG_UNIX)
8693 if (ctx
->ring_sock
) {
8694 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8695 sock_release(ctx
->ring_sock
);
8699 io_mem_free(ctx
->rings
);
8700 io_mem_free(ctx
->sq_sqes
);
8702 percpu_ref_exit(&ctx
->refs
);
8703 free_uid(ctx
->user
);
8704 io_req_caches_free(ctx
);
8706 io_wq_put_hash(ctx
->hash_map
);
8707 kfree(ctx
->cancel_hash
);
8708 kfree(ctx
->dummy_ubuf
);
8712 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8714 struct io_ring_ctx
*ctx
= file
->private_data
;
8717 poll_wait(file
, &ctx
->poll_wait
, wait
);
8719 * synchronizes with barrier from wq_has_sleeper call in
8723 if (!io_sqring_full(ctx
))
8724 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8727 * Don't flush cqring overflow list here, just do a simple check.
8728 * Otherwise there could possible be ABBA deadlock:
8731 * lock(&ctx->uring_lock);
8733 * lock(&ctx->uring_lock);
8736 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
8737 * pushs them to do the flush.
8739 if (io_cqring_events(ctx
) || test_bit(0, &ctx
->check_cq_overflow
))
8740 mask
|= EPOLLIN
| EPOLLRDNORM
;
8745 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8747 struct io_ring_ctx
*ctx
= file
->private_data
;
8749 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8752 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
8754 const struct cred
*creds
;
8756 creds
= xa_erase(&ctx
->personalities
, id
);
8765 struct io_tctx_exit
{
8766 struct callback_head task_work
;
8767 struct completion completion
;
8768 struct io_ring_ctx
*ctx
;
8771 static void io_tctx_exit_cb(struct callback_head
*cb
)
8773 struct io_uring_task
*tctx
= current
->io_uring
;
8774 struct io_tctx_exit
*work
;
8776 work
= container_of(cb
, struct io_tctx_exit
, task_work
);
8778 * When @in_idle, we're in cancellation and it's racy to remove the
8779 * node. It'll be removed by the end of cancellation, just ignore it.
8781 if (!atomic_read(&tctx
->in_idle
))
8782 io_uring_del_tctx_node((unsigned long)work
->ctx
);
8783 complete(&work
->completion
);
8786 static bool io_cancel_ctx_cb(struct io_wq_work
*work
, void *data
)
8788 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8790 return req
->ctx
== data
;
8793 static void io_ring_exit_work(struct work_struct
*work
)
8795 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
, exit_work
);
8796 unsigned long timeout
= jiffies
+ HZ
* 60 * 5;
8797 struct io_tctx_exit exit
;
8798 struct io_tctx_node
*node
;
8802 * If we're doing polled IO and end up having requests being
8803 * submitted async (out-of-line), then completions can come in while
8804 * we're waiting for refs to drop. We need to reap these manually,
8805 * as nobody else will be looking for them.
8808 io_uring_try_cancel_requests(ctx
, NULL
, true);
8810 struct io_sq_data
*sqd
= ctx
->sq_data
;
8811 struct task_struct
*tsk
;
8813 io_sq_thread_park(sqd
);
8815 if (tsk
&& tsk
->io_uring
&& tsk
->io_uring
->io_wq
)
8816 io_wq_cancel_cb(tsk
->io_uring
->io_wq
,
8817 io_cancel_ctx_cb
, ctx
, true);
8818 io_sq_thread_unpark(sqd
);
8821 WARN_ON_ONCE(time_after(jiffies
, timeout
));
8822 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8824 init_completion(&exit
.completion
);
8825 init_task_work(&exit
.task_work
, io_tctx_exit_cb
);
8828 * Some may use context even when all refs and requests have been put,
8829 * and they are free to do so while still holding uring_lock or
8830 * completion_lock, see io_req_task_submit(). Apart from other work,
8831 * this lock/unlock section also waits them to finish.
8833 mutex_lock(&ctx
->uring_lock
);
8834 while (!list_empty(&ctx
->tctx_list
)) {
8835 WARN_ON_ONCE(time_after(jiffies
, timeout
));
8837 node
= list_first_entry(&ctx
->tctx_list
, struct io_tctx_node
,
8839 /* don't spin on a single task if cancellation failed */
8840 list_rotate_left(&ctx
->tctx_list
);
8841 ret
= task_work_add(node
->task
, &exit
.task_work
, TWA_SIGNAL
);
8842 if (WARN_ON_ONCE(ret
))
8844 wake_up_process(node
->task
);
8846 mutex_unlock(&ctx
->uring_lock
);
8847 wait_for_completion(&exit
.completion
);
8848 mutex_lock(&ctx
->uring_lock
);
8850 mutex_unlock(&ctx
->uring_lock
);
8851 spin_lock_irq(&ctx
->completion_lock
);
8852 spin_unlock_irq(&ctx
->completion_lock
);
8854 io_ring_ctx_free(ctx
);
8857 /* Returns true if we found and killed one or more timeouts */
8858 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
8861 struct io_kiocb
*req
, *tmp
;
8864 spin_lock_irq(&ctx
->completion_lock
);
8865 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
8866 if (io_match_task(req
, tsk
, cancel_all
)) {
8867 io_kill_timeout(req
, -ECANCELED
);
8872 io_commit_cqring(ctx
);
8873 spin_unlock_irq(&ctx
->completion_lock
);
8875 io_cqring_ev_posted(ctx
);
8876 return canceled
!= 0;
8879 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8881 unsigned long index
;
8882 struct creds
*creds
;
8884 mutex_lock(&ctx
->uring_lock
);
8885 percpu_ref_kill(&ctx
->refs
);
8887 __io_cqring_overflow_flush(ctx
, true);
8888 xa_for_each(&ctx
->personalities
, index
, creds
)
8889 io_unregister_personality(ctx
, index
);
8890 mutex_unlock(&ctx
->uring_lock
);
8892 io_kill_timeouts(ctx
, NULL
, true);
8893 io_poll_remove_all(ctx
, NULL
, true);
8895 /* if we failed setting up the ctx, we might not have any rings */
8896 io_iopoll_try_reap_events(ctx
);
8898 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8900 * Use system_unbound_wq to avoid spawning tons of event kworkers
8901 * if we're exiting a ton of rings at the same time. It just adds
8902 * noise and overhead, there's no discernable change in runtime
8903 * over using system_wq.
8905 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8908 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8910 struct io_ring_ctx
*ctx
= file
->private_data
;
8912 file
->private_data
= NULL
;
8913 io_ring_ctx_wait_and_kill(ctx
);
8917 struct io_task_cancel
{
8918 struct task_struct
*task
;
8922 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8924 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8925 struct io_task_cancel
*cancel
= data
;
8928 if (!cancel
->all
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
8929 unsigned long flags
;
8930 struct io_ring_ctx
*ctx
= req
->ctx
;
8932 /* protect against races with linked timeouts */
8933 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
8934 ret
= io_match_task(req
, cancel
->task
, cancel
->all
);
8935 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
8937 ret
= io_match_task(req
, cancel
->task
, cancel
->all
);
8942 static bool io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8943 struct task_struct
*task
, bool cancel_all
)
8945 struct io_defer_entry
*de
;
8948 spin_lock_irq(&ctx
->completion_lock
);
8949 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8950 if (io_match_task(de
->req
, task
, cancel_all
)) {
8951 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8955 spin_unlock_irq(&ctx
->completion_lock
);
8956 if (list_empty(&list
))
8959 while (!list_empty(&list
)) {
8960 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8961 list_del_init(&de
->list
);
8962 io_req_complete_failed(de
->req
, -ECANCELED
);
8968 static bool io_uring_try_cancel_iowq(struct io_ring_ctx
*ctx
)
8970 struct io_tctx_node
*node
;
8971 enum io_wq_cancel cret
;
8974 mutex_lock(&ctx
->uring_lock
);
8975 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
8976 struct io_uring_task
*tctx
= node
->task
->io_uring
;
8979 * io_wq will stay alive while we hold uring_lock, because it's
8980 * killed after ctx nodes, which requires to take the lock.
8982 if (!tctx
|| !tctx
->io_wq
)
8984 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_ctx_cb
, ctx
, true);
8985 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
8987 mutex_unlock(&ctx
->uring_lock
);
8992 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
8993 struct task_struct
*task
,
8996 struct io_task_cancel cancel
= { .task
= task
, .all
= cancel_all
, };
8997 struct io_uring_task
*tctx
= task
? task
->io_uring
: NULL
;
9000 enum io_wq_cancel cret
;
9004 ret
|= io_uring_try_cancel_iowq(ctx
);
9005 } else if (tctx
&& tctx
->io_wq
) {
9007 * Cancels requests of all rings, not only @ctx, but
9008 * it's fine as the task is in exit/exec.
9010 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_task_cb
,
9012 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
9015 /* SQPOLL thread does its own polling */
9016 if ((!(ctx
->flags
& IORING_SETUP_SQPOLL
) && cancel_all
) ||
9017 (ctx
->sq_data
&& ctx
->sq_data
->thread
== current
)) {
9018 while (!list_empty_careful(&ctx
->iopoll_list
)) {
9019 io_iopoll_try_reap_events(ctx
);
9024 ret
|= io_cancel_defer_files(ctx
, task
, cancel_all
);
9025 ret
|= io_poll_remove_all(ctx
, task
, cancel_all
);
9026 ret
|= io_kill_timeouts(ctx
, task
, cancel_all
);
9028 ret
|= io_run_task_work();
9035 static int __io_uring_add_tctx_node(struct io_ring_ctx
*ctx
)
9037 struct io_uring_task
*tctx
= current
->io_uring
;
9038 struct io_tctx_node
*node
;
9041 if (unlikely(!tctx
)) {
9042 ret
= io_uring_alloc_task_context(current
, ctx
);
9045 tctx
= current
->io_uring
;
9047 if (!xa_load(&tctx
->xa
, (unsigned long)ctx
)) {
9048 node
= kmalloc(sizeof(*node
), GFP_KERNEL
);
9052 node
->task
= current
;
9054 ret
= xa_err(xa_store(&tctx
->xa
, (unsigned long)ctx
,
9061 mutex_lock(&ctx
->uring_lock
);
9062 list_add(&node
->ctx_node
, &ctx
->tctx_list
);
9063 mutex_unlock(&ctx
->uring_lock
);
9070 * Note that this task has used io_uring. We use it for cancelation purposes.
9072 static inline int io_uring_add_tctx_node(struct io_ring_ctx
*ctx
)
9074 struct io_uring_task
*tctx
= current
->io_uring
;
9076 if (likely(tctx
&& tctx
->last
== ctx
))
9078 return __io_uring_add_tctx_node(ctx
);
9082 * Remove this io_uring_file -> task mapping.
9084 static void io_uring_del_tctx_node(unsigned long index
)
9086 struct io_uring_task
*tctx
= current
->io_uring
;
9087 struct io_tctx_node
*node
;
9091 node
= xa_erase(&tctx
->xa
, index
);
9095 WARN_ON_ONCE(current
!= node
->task
);
9096 WARN_ON_ONCE(list_empty(&node
->ctx_node
));
9098 mutex_lock(&node
->ctx
->uring_lock
);
9099 list_del(&node
->ctx_node
);
9100 mutex_unlock(&node
->ctx
->uring_lock
);
9102 if (tctx
->last
== node
->ctx
)
9107 static void io_uring_clean_tctx(struct io_uring_task
*tctx
)
9109 struct io_wq
*wq
= tctx
->io_wq
;
9110 struct io_tctx_node
*node
;
9111 unsigned long index
;
9113 xa_for_each(&tctx
->xa
, index
, node
)
9114 io_uring_del_tctx_node(index
);
9117 * Must be after io_uring_del_task_file() (removes nodes under
9118 * uring_lock) to avoid race with io_uring_try_cancel_iowq().
9121 io_wq_put_and_exit(wq
);
9125 static s64
tctx_inflight(struct io_uring_task
*tctx
, bool tracked
)
9128 return atomic_read(&tctx
->inflight_tracked
);
9129 return percpu_counter_sum(&tctx
->inflight
);
9132 static void io_uring_drop_tctx_refs(struct task_struct
*task
)
9134 struct io_uring_task
*tctx
= task
->io_uring
;
9135 unsigned int refs
= tctx
->cached_refs
;
9137 tctx
->cached_refs
= 0;
9138 percpu_counter_sub(&tctx
->inflight
, refs
);
9139 put_task_struct_many(task
, refs
);
9143 * Find any io_uring ctx that this task has registered or done IO on, and cancel
9144 * requests. @sqd should be not-null IIF it's an SQPOLL thread cancellation.
9146 static void io_uring_cancel_generic(bool cancel_all
, struct io_sq_data
*sqd
)
9148 struct io_uring_task
*tctx
= current
->io_uring
;
9149 struct io_ring_ctx
*ctx
;
9153 WARN_ON_ONCE(sqd
&& sqd
->thread
!= current
);
9155 if (!current
->io_uring
)
9158 io_wq_exit_start(tctx
->io_wq
);
9160 io_uring_drop_tctx_refs(current
);
9161 atomic_inc(&tctx
->in_idle
);
9163 /* read completions before cancelations */
9164 inflight
= tctx_inflight(tctx
, !cancel_all
);
9169 struct io_tctx_node
*node
;
9170 unsigned long index
;
9172 xa_for_each(&tctx
->xa
, index
, node
) {
9173 /* sqpoll task will cancel all its requests */
9174 if (node
->ctx
->sq_data
)
9176 io_uring_try_cancel_requests(node
->ctx
, current
,
9180 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
9181 io_uring_try_cancel_requests(ctx
, current
,
9185 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
9187 * If we've seen completions, retry without waiting. This
9188 * avoids a race where a completion comes in before we did
9189 * prepare_to_wait().
9191 if (inflight
== tctx_inflight(tctx
, !cancel_all
))
9193 finish_wait(&tctx
->wait
, &wait
);
9195 atomic_dec(&tctx
->in_idle
);
9197 io_uring_clean_tctx(tctx
);
9199 /* for exec all current's requests should be gone, kill tctx */
9200 __io_uring_free(current
);
9204 void __io_uring_cancel(struct files_struct
*files
)
9206 io_uring_cancel_generic(!files
, NULL
);
9209 static void *io_uring_validate_mmap_request(struct file
*file
,
9210 loff_t pgoff
, size_t sz
)
9212 struct io_ring_ctx
*ctx
= file
->private_data
;
9213 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9218 case IORING_OFF_SQ_RING
:
9219 case IORING_OFF_CQ_RING
:
9222 case IORING_OFF_SQES
:
9226 return ERR_PTR(-EINVAL
);
9229 page
= virt_to_head_page(ptr
);
9230 if (sz
> page_size(page
))
9231 return ERR_PTR(-EINVAL
);
9238 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9240 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9244 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9246 return PTR_ERR(ptr
);
9248 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9249 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9252 #else /* !CONFIG_MMU */
9254 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9256 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9259 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9261 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9264 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9265 unsigned long addr
, unsigned long len
,
9266 unsigned long pgoff
, unsigned long flags
)
9270 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9272 return PTR_ERR(ptr
);
9274 return (unsigned long) ptr
;
9277 #endif /* !CONFIG_MMU */
9279 static int io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9284 if (!io_sqring_full(ctx
))
9286 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9288 if (!io_sqring_full(ctx
))
9291 } while (!signal_pending(current
));
9293 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9297 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9298 struct __kernel_timespec __user
**ts
,
9299 const sigset_t __user
**sig
)
9301 struct io_uring_getevents_arg arg
;
9304 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9305 * is just a pointer to the sigset_t.
9307 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9308 *sig
= (const sigset_t __user
*) argp
;
9314 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9315 * timespec and sigset_t pointers if good.
9317 if (*argsz
!= sizeof(arg
))
9319 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9321 *sig
= u64_to_user_ptr(arg
.sigmask
);
9322 *argsz
= arg
.sigmask_sz
;
9323 *ts
= u64_to_user_ptr(arg
.ts
);
9327 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9328 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9331 struct io_ring_ctx
*ctx
;
9338 if (unlikely(flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9339 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
)))
9343 if (unlikely(!f
.file
))
9347 if (unlikely(f
.file
->f_op
!= &io_uring_fops
))
9351 ctx
= f
.file
->private_data
;
9352 if (unlikely(!percpu_ref_tryget(&ctx
->refs
)))
9356 if (unlikely(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9360 * For SQ polling, the thread will do all submissions and completions.
9361 * Just return the requested submit count, and wake the thread if
9365 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9366 io_cqring_overflow_flush(ctx
, false);
9369 if (unlikely(ctx
->sq_data
->thread
== NULL
))
9371 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9372 wake_up(&ctx
->sq_data
->wait
);
9373 if (flags
& IORING_ENTER_SQ_WAIT
) {
9374 ret
= io_sqpoll_wait_sq(ctx
);
9378 submitted
= to_submit
;
9379 } else if (to_submit
) {
9380 ret
= io_uring_add_tctx_node(ctx
);
9383 mutex_lock(&ctx
->uring_lock
);
9384 submitted
= io_submit_sqes(ctx
, to_submit
);
9385 mutex_unlock(&ctx
->uring_lock
);
9387 if (submitted
!= to_submit
)
9390 if (flags
& IORING_ENTER_GETEVENTS
) {
9391 const sigset_t __user
*sig
;
9392 struct __kernel_timespec __user
*ts
;
9394 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
9398 min_complete
= min(min_complete
, ctx
->cq_entries
);
9401 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9402 * space applications don't need to do io completion events
9403 * polling again, they can rely on io_sq_thread to do polling
9404 * work, which can reduce cpu usage and uring_lock contention.
9406 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
9407 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9408 ret
= io_iopoll_check(ctx
, min_complete
);
9410 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
9415 percpu_ref_put(&ctx
->refs
);
9418 return submitted
? submitted
: ret
;
9421 #ifdef CONFIG_PROC_FS
9422 static int io_uring_show_cred(struct seq_file
*m
, unsigned int id
,
9423 const struct cred
*cred
)
9425 struct user_namespace
*uns
= seq_user_ns(m
);
9426 struct group_info
*gi
;
9431 seq_printf(m
, "%5d\n", id
);
9432 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
9433 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
9434 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
9435 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
9436 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
9437 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
9438 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
9439 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
9440 seq_puts(m
, "\n\tGroups:\t");
9441 gi
= cred
->group_info
;
9442 for (g
= 0; g
< gi
->ngroups
; g
++) {
9443 seq_put_decimal_ull(m
, g
? " " : "",
9444 from_kgid_munged(uns
, gi
->gid
[g
]));
9446 seq_puts(m
, "\n\tCapEff:\t");
9447 cap
= cred
->cap_effective
;
9448 CAP_FOR_EACH_U32(__capi
)
9449 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
9454 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
9456 struct io_sq_data
*sq
= NULL
;
9461 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9462 * since fdinfo case grabs it in the opposite direction of normal use
9463 * cases. If we fail to get the lock, we just don't iterate any
9464 * structures that could be going away outside the io_uring mutex.
9466 has_lock
= mutex_trylock(&ctx
->uring_lock
);
9468 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
)) {
9474 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
9475 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
9476 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
9477 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
9478 struct file
*f
= io_file_from_index(ctx
, i
);
9481 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
9483 seq_printf(m
, "%5u: <none>\n", i
);
9485 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
9486 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
9487 struct io_mapped_ubuf
*buf
= ctx
->user_bufs
[i
];
9488 unsigned int len
= buf
->ubuf_end
- buf
->ubuf
;
9490 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
, len
);
9492 if (has_lock
&& !xa_empty(&ctx
->personalities
)) {
9493 unsigned long index
;
9494 const struct cred
*cred
;
9496 seq_printf(m
, "Personalities:\n");
9497 xa_for_each(&ctx
->personalities
, index
, cred
)
9498 io_uring_show_cred(m
, index
, cred
);
9500 seq_printf(m
, "PollList:\n");
9501 spin_lock_irq(&ctx
->completion_lock
);
9502 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9503 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9504 struct io_kiocb
*req
;
9506 hlist_for_each_entry(req
, list
, hash_node
)
9507 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9508 req
->task
->task_works
!= NULL
);
9510 spin_unlock_irq(&ctx
->completion_lock
);
9512 mutex_unlock(&ctx
->uring_lock
);
9515 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9517 struct io_ring_ctx
*ctx
= f
->private_data
;
9519 if (percpu_ref_tryget(&ctx
->refs
)) {
9520 __io_uring_show_fdinfo(ctx
, m
);
9521 percpu_ref_put(&ctx
->refs
);
9526 static const struct file_operations io_uring_fops
= {
9527 .release
= io_uring_release
,
9528 .mmap
= io_uring_mmap
,
9530 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9531 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9533 .poll
= io_uring_poll
,
9534 .fasync
= io_uring_fasync
,
9535 #ifdef CONFIG_PROC_FS
9536 .show_fdinfo
= io_uring_show_fdinfo
,
9540 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9541 struct io_uring_params
*p
)
9543 struct io_rings
*rings
;
9544 size_t size
, sq_array_offset
;
9546 /* make sure these are sane, as we already accounted them */
9547 ctx
->sq_entries
= p
->sq_entries
;
9548 ctx
->cq_entries
= p
->cq_entries
;
9550 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9551 if (size
== SIZE_MAX
)
9554 rings
= io_mem_alloc(size
);
9559 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9560 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9561 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9562 rings
->sq_ring_entries
= p
->sq_entries
;
9563 rings
->cq_ring_entries
= p
->cq_entries
;
9565 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9566 if (size
== SIZE_MAX
) {
9567 io_mem_free(ctx
->rings
);
9572 ctx
->sq_sqes
= io_mem_alloc(size
);
9573 if (!ctx
->sq_sqes
) {
9574 io_mem_free(ctx
->rings
);
9582 static int io_uring_install_fd(struct io_ring_ctx
*ctx
, struct file
*file
)
9586 fd
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9590 ret
= io_uring_add_tctx_node(ctx
);
9595 fd_install(fd
, file
);
9600 * Allocate an anonymous fd, this is what constitutes the application
9601 * visible backing of an io_uring instance. The application mmaps this
9602 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9603 * we have to tie this fd to a socket for file garbage collection purposes.
9605 static struct file
*io_uring_get_file(struct io_ring_ctx
*ctx
)
9608 #if defined(CONFIG_UNIX)
9611 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9614 return ERR_PTR(ret
);
9617 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9618 O_RDWR
| O_CLOEXEC
);
9619 #if defined(CONFIG_UNIX)
9621 sock_release(ctx
->ring_sock
);
9622 ctx
->ring_sock
= NULL
;
9624 ctx
->ring_sock
->file
= file
;
9630 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9631 struct io_uring_params __user
*params
)
9633 struct io_ring_ctx
*ctx
;
9639 if (entries
> IORING_MAX_ENTRIES
) {
9640 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9642 entries
= IORING_MAX_ENTRIES
;
9646 * Use twice as many entries for the CQ ring. It's possible for the
9647 * application to drive a higher depth than the size of the SQ ring,
9648 * since the sqes are only used at submission time. This allows for
9649 * some flexibility in overcommitting a bit. If the application has
9650 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9651 * of CQ ring entries manually.
9653 p
->sq_entries
= roundup_pow_of_two(entries
);
9654 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9656 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9657 * to a power-of-two, if it isn't already. We do NOT impose
9658 * any cq vs sq ring sizing.
9662 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9663 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9665 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9667 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9668 if (p
->cq_entries
< p
->sq_entries
)
9671 p
->cq_entries
= 2 * p
->sq_entries
;
9674 ctx
= io_ring_ctx_alloc(p
);
9677 ctx
->compat
= in_compat_syscall();
9678 if (!capable(CAP_IPC_LOCK
))
9679 ctx
->user
= get_uid(current_user());
9682 * This is just grabbed for accounting purposes. When a process exits,
9683 * the mm is exited and dropped before the files, hence we need to hang
9684 * on to this mm purely for the purposes of being able to unaccount
9685 * memory (locked/pinned vm). It's not used for anything else.
9687 mmgrab(current
->mm
);
9688 ctx
->mm_account
= current
->mm
;
9690 ret
= io_allocate_scq_urings(ctx
, p
);
9694 ret
= io_sq_offload_create(ctx
, p
);
9697 /* always set a rsrc node */
9698 ret
= io_rsrc_node_switch_start(ctx
);
9701 io_rsrc_node_switch(ctx
, NULL
);
9703 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9704 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9705 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9706 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9707 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9708 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9709 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9710 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9712 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9713 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9714 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9715 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9716 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9717 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9718 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9719 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9721 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9722 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9723 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9724 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
9725 IORING_FEAT_EXT_ARG
| IORING_FEAT_NATIVE_WORKERS
|
9726 IORING_FEAT_RSRC_TAGS
;
9728 if (copy_to_user(params
, p
, sizeof(*p
))) {
9733 file
= io_uring_get_file(ctx
);
9735 ret
= PTR_ERR(file
);
9740 * Install ring fd as the very last thing, so we don't risk someone
9741 * having closed it before we finish setup
9743 ret
= io_uring_install_fd(ctx
, file
);
9745 /* fput will clean it up */
9750 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9753 io_ring_ctx_wait_and_kill(ctx
);
9758 * Sets up an aio uring context, and returns the fd. Applications asks for a
9759 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9760 * params structure passed in.
9762 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9764 struct io_uring_params p
;
9767 if (copy_from_user(&p
, params
, sizeof(p
)))
9769 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9774 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9775 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9776 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9777 IORING_SETUP_R_DISABLED
))
9780 return io_uring_create(entries
, &p
, params
);
9783 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9784 struct io_uring_params __user
*, params
)
9786 return io_uring_setup(entries
, params
);
9789 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9791 struct io_uring_probe
*p
;
9795 size
= struct_size(p
, ops
, nr_args
);
9796 if (size
== SIZE_MAX
)
9798 p
= kzalloc(size
, GFP_KERNEL
);
9803 if (copy_from_user(p
, arg
, size
))
9806 if (memchr_inv(p
, 0, size
))
9809 p
->last_op
= IORING_OP_LAST
- 1;
9810 if (nr_args
> IORING_OP_LAST
)
9811 nr_args
= IORING_OP_LAST
;
9813 for (i
= 0; i
< nr_args
; i
++) {
9815 if (!io_op_defs
[i
].not_supported
)
9816 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9821 if (copy_to_user(arg
, p
, size
))
9828 static int io_register_personality(struct io_ring_ctx
*ctx
)
9830 const struct cred
*creds
;
9834 creds
= get_current_cred();
9836 ret
= xa_alloc_cyclic(&ctx
->personalities
, &id
, (void *)creds
,
9837 XA_LIMIT(0, USHRT_MAX
), &ctx
->pers_next
, GFP_KERNEL
);
9844 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9845 unsigned int nr_args
)
9847 struct io_uring_restriction
*res
;
9851 /* Restrictions allowed only if rings started disabled */
9852 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9855 /* We allow only a single restrictions registration */
9856 if (ctx
->restrictions
.registered
)
9859 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9862 size
= array_size(nr_args
, sizeof(*res
));
9863 if (size
== SIZE_MAX
)
9866 res
= memdup_user(arg
, size
);
9868 return PTR_ERR(res
);
9872 for (i
= 0; i
< nr_args
; i
++) {
9873 switch (res
[i
].opcode
) {
9874 case IORING_RESTRICTION_REGISTER_OP
:
9875 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9880 __set_bit(res
[i
].register_op
,
9881 ctx
->restrictions
.register_op
);
9883 case IORING_RESTRICTION_SQE_OP
:
9884 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9889 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9891 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9892 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9894 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9895 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9904 /* Reset all restrictions if an error happened */
9906 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9908 ctx
->restrictions
.registered
= true;
9914 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9916 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9919 if (ctx
->restrictions
.registered
)
9920 ctx
->restricted
= 1;
9922 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9923 if (ctx
->sq_data
&& wq_has_sleeper(&ctx
->sq_data
->wait
))
9924 wake_up(&ctx
->sq_data
->wait
);
9928 static int __io_register_rsrc_update(struct io_ring_ctx
*ctx
, unsigned type
,
9929 struct io_uring_rsrc_update2
*up
,
9937 if (check_add_overflow(up
->offset
, nr_args
, &tmp
))
9939 err
= io_rsrc_node_switch_start(ctx
);
9944 case IORING_RSRC_FILE
:
9945 return __io_sqe_files_update(ctx
, up
, nr_args
);
9946 case IORING_RSRC_BUFFER
:
9947 return __io_sqe_buffers_update(ctx
, up
, nr_args
);
9952 static int io_register_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
9955 struct io_uring_rsrc_update2 up
;
9959 memset(&up
, 0, sizeof(up
));
9960 if (copy_from_user(&up
, arg
, sizeof(struct io_uring_rsrc_update
)))
9962 return __io_register_rsrc_update(ctx
, IORING_RSRC_FILE
, &up
, nr_args
);
9965 static int io_register_rsrc_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
9966 unsigned size
, unsigned type
)
9968 struct io_uring_rsrc_update2 up
;
9970 if (size
!= sizeof(up
))
9972 if (copy_from_user(&up
, arg
, sizeof(up
)))
9974 if (!up
.nr
|| up
.resv
)
9976 return __io_register_rsrc_update(ctx
, type
, &up
, up
.nr
);
9979 static int io_register_rsrc(struct io_ring_ctx
*ctx
, void __user
*arg
,
9980 unsigned int size
, unsigned int type
)
9982 struct io_uring_rsrc_register rr
;
9984 /* keep it extendible */
9985 if (size
!= sizeof(rr
))
9988 memset(&rr
, 0, sizeof(rr
));
9989 if (copy_from_user(&rr
, arg
, size
))
9991 if (!rr
.nr
|| rr
.resv
|| rr
.resv2
)
9995 case IORING_RSRC_FILE
:
9996 return io_sqe_files_register(ctx
, u64_to_user_ptr(rr
.data
),
9997 rr
.nr
, u64_to_user_ptr(rr
.tags
));
9998 case IORING_RSRC_BUFFER
:
9999 return io_sqe_buffers_register(ctx
, u64_to_user_ptr(rr
.data
),
10000 rr
.nr
, u64_to_user_ptr(rr
.tags
));
10005 static int io_register_iowq_aff(struct io_ring_ctx
*ctx
, void __user
*arg
,
10008 struct io_uring_task
*tctx
= current
->io_uring
;
10009 cpumask_var_t new_mask
;
10012 if (!tctx
|| !tctx
->io_wq
)
10015 if (!alloc_cpumask_var(&new_mask
, GFP_KERNEL
))
10018 cpumask_clear(new_mask
);
10019 if (len
> cpumask_size())
10020 len
= cpumask_size();
10022 if (copy_from_user(new_mask
, arg
, len
)) {
10023 free_cpumask_var(new_mask
);
10027 ret
= io_wq_cpu_affinity(tctx
->io_wq
, new_mask
);
10028 free_cpumask_var(new_mask
);
10032 static int io_unregister_iowq_aff(struct io_ring_ctx
*ctx
)
10034 struct io_uring_task
*tctx
= current
->io_uring
;
10036 if (!tctx
|| !tctx
->io_wq
)
10039 return io_wq_cpu_affinity(tctx
->io_wq
, NULL
);
10042 static bool io_register_op_must_quiesce(int op
)
10045 case IORING_REGISTER_BUFFERS
:
10046 case IORING_UNREGISTER_BUFFERS
:
10047 case IORING_REGISTER_FILES
:
10048 case IORING_UNREGISTER_FILES
:
10049 case IORING_REGISTER_FILES_UPDATE
:
10050 case IORING_REGISTER_PROBE
:
10051 case IORING_REGISTER_PERSONALITY
:
10052 case IORING_UNREGISTER_PERSONALITY
:
10053 case IORING_REGISTER_FILES2
:
10054 case IORING_REGISTER_FILES_UPDATE2
:
10055 case IORING_REGISTER_BUFFERS2
:
10056 case IORING_REGISTER_BUFFERS_UPDATE
:
10057 case IORING_REGISTER_IOWQ_AFF
:
10058 case IORING_UNREGISTER_IOWQ_AFF
:
10065 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
10066 void __user
*arg
, unsigned nr_args
)
10067 __releases(ctx
->uring_lock
)
10068 __acquires(ctx
->uring_lock
)
10073 * We're inside the ring mutex, if the ref is already dying, then
10074 * someone else killed the ctx or is already going through
10075 * io_uring_register().
10077 if (percpu_ref_is_dying(&ctx
->refs
))
10080 if (ctx
->restricted
) {
10081 if (opcode
>= IORING_REGISTER_LAST
)
10083 opcode
= array_index_nospec(opcode
, IORING_REGISTER_LAST
);
10084 if (!test_bit(opcode
, ctx
->restrictions
.register_op
))
10088 if (io_register_op_must_quiesce(opcode
)) {
10089 percpu_ref_kill(&ctx
->refs
);
10092 * Drop uring mutex before waiting for references to exit. If
10093 * another thread is currently inside io_uring_enter() it might
10094 * need to grab the uring_lock to make progress. If we hold it
10095 * here across the drain wait, then we can deadlock. It's safe
10096 * to drop the mutex here, since no new references will come in
10097 * after we've killed the percpu ref.
10099 mutex_unlock(&ctx
->uring_lock
);
10101 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
10104 ret
= io_run_task_work_sig();
10108 mutex_lock(&ctx
->uring_lock
);
10111 io_refs_resurrect(&ctx
->refs
, &ctx
->ref_comp
);
10117 case IORING_REGISTER_BUFFERS
:
10118 ret
= io_sqe_buffers_register(ctx
, arg
, nr_args
, NULL
);
10120 case IORING_UNREGISTER_BUFFERS
:
10122 if (arg
|| nr_args
)
10124 ret
= io_sqe_buffers_unregister(ctx
);
10126 case IORING_REGISTER_FILES
:
10127 ret
= io_sqe_files_register(ctx
, arg
, nr_args
, NULL
);
10129 case IORING_UNREGISTER_FILES
:
10131 if (arg
|| nr_args
)
10133 ret
= io_sqe_files_unregister(ctx
);
10135 case IORING_REGISTER_FILES_UPDATE
:
10136 ret
= io_register_files_update(ctx
, arg
, nr_args
);
10138 case IORING_REGISTER_EVENTFD
:
10139 case IORING_REGISTER_EVENTFD_ASYNC
:
10143 ret
= io_eventfd_register(ctx
, arg
);
10146 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
10147 ctx
->eventfd_async
= 1;
10149 ctx
->eventfd_async
= 0;
10151 case IORING_UNREGISTER_EVENTFD
:
10153 if (arg
|| nr_args
)
10155 ret
= io_eventfd_unregister(ctx
);
10157 case IORING_REGISTER_PROBE
:
10159 if (!arg
|| nr_args
> 256)
10161 ret
= io_probe(ctx
, arg
, nr_args
);
10163 case IORING_REGISTER_PERSONALITY
:
10165 if (arg
|| nr_args
)
10167 ret
= io_register_personality(ctx
);
10169 case IORING_UNREGISTER_PERSONALITY
:
10173 ret
= io_unregister_personality(ctx
, nr_args
);
10175 case IORING_REGISTER_ENABLE_RINGS
:
10177 if (arg
|| nr_args
)
10179 ret
= io_register_enable_rings(ctx
);
10181 case IORING_REGISTER_RESTRICTIONS
:
10182 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
10184 case IORING_REGISTER_FILES2
:
10185 ret
= io_register_rsrc(ctx
, arg
, nr_args
, IORING_RSRC_FILE
);
10187 case IORING_REGISTER_FILES_UPDATE2
:
10188 ret
= io_register_rsrc_update(ctx
, arg
, nr_args
,
10191 case IORING_REGISTER_BUFFERS2
:
10192 ret
= io_register_rsrc(ctx
, arg
, nr_args
, IORING_RSRC_BUFFER
);
10194 case IORING_REGISTER_BUFFERS_UPDATE
:
10195 ret
= io_register_rsrc_update(ctx
, arg
, nr_args
,
10196 IORING_RSRC_BUFFER
);
10198 case IORING_REGISTER_IOWQ_AFF
:
10200 if (!arg
|| !nr_args
)
10202 ret
= io_register_iowq_aff(ctx
, arg
, nr_args
);
10204 case IORING_UNREGISTER_IOWQ_AFF
:
10206 if (arg
|| nr_args
)
10208 ret
= io_unregister_iowq_aff(ctx
);
10215 if (io_register_op_must_quiesce(opcode
)) {
10216 /* bring the ctx back to life */
10217 percpu_ref_reinit(&ctx
->refs
);
10218 reinit_completion(&ctx
->ref_comp
);
10223 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
10224 void __user
*, arg
, unsigned int, nr_args
)
10226 struct io_ring_ctx
*ctx
;
10235 if (f
.file
->f_op
!= &io_uring_fops
)
10238 ctx
= f
.file
->private_data
;
10240 io_run_task_work();
10242 mutex_lock(&ctx
->uring_lock
);
10243 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
10244 mutex_unlock(&ctx
->uring_lock
);
10245 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
10246 ctx
->cq_ev_fd
!= NULL
, ret
);
10252 static int __init
io_uring_init(void)
10254 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10255 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10256 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10259 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10260 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10261 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
10262 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
10263 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
10264 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
10265 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
10266 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
10267 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
10268 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
10269 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
10270 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
10271 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
10272 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
10273 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
10274 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
10275 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
10276 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
10277 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
10278 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
10279 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
10280 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
10281 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
10282 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
10283 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
10284 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
10285 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
10286 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
10287 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
10288 BUILD_BUG_SQE_ELEM(40, __u16
, buf_group
);
10289 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
10290 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
10292 BUILD_BUG_ON(sizeof(struct io_uring_files_update
) !=
10293 sizeof(struct io_uring_rsrc_update
));
10294 BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update
) >
10295 sizeof(struct io_uring_rsrc_update2
));
10296 /* should fit into one byte */
10297 BUILD_BUG_ON(SQE_VALID_FLAGS
>= (1 << 8));
10299 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
10300 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
10302 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
|
10306 __initcall(io_uring_init
);