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>
81 #include <linux/tracehook.h>
83 #define CREATE_TRACE_POINTS
84 #include <trace/events/io_uring.h>
86 #include <uapi/linux/io_uring.h>
91 #define IORING_MAX_ENTRIES 32768
92 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
93 #define IORING_SQPOLL_CAP_ENTRIES_VALUE 8
96 #define IORING_MAX_FIXED_FILES (1U << 15)
97 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
98 IORING_REGISTER_LAST + IORING_OP_LAST)
100 #define IO_RSRC_TAG_TABLE_SHIFT (PAGE_SHIFT - 3)
101 #define IO_RSRC_TAG_TABLE_MAX (1U << IO_RSRC_TAG_TABLE_SHIFT)
102 #define IO_RSRC_TAG_TABLE_MASK (IO_RSRC_TAG_TABLE_MAX - 1)
104 #define IORING_MAX_REG_BUFFERS (1U << 14)
106 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
107 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
109 #define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
110 REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS)
112 #define IO_TCTX_REFS_CACHE_NR (1U << 10)
115 u32 head ____cacheline_aligned_in_smp
;
116 u32 tail ____cacheline_aligned_in_smp
;
120 * This data is shared with the application through the mmap at offsets
121 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
123 * The offsets to the member fields are published through struct
124 * io_sqring_offsets when calling io_uring_setup.
128 * Head and tail offsets into the ring; the offsets need to be
129 * masked to get valid indices.
131 * The kernel controls head of the sq ring and the tail of the cq ring,
132 * and the application controls tail of the sq ring and the head of the
135 struct io_uring sq
, cq
;
137 * Bitmasks to apply to head and tail offsets (constant, equals
140 u32 sq_ring_mask
, cq_ring_mask
;
141 /* Ring sizes (constant, power of 2) */
142 u32 sq_ring_entries
, cq_ring_entries
;
144 * Number of invalid entries dropped by the kernel due to
145 * invalid index stored in array
147 * Written by the kernel, shouldn't be modified by the
148 * application (i.e. get number of "new events" by comparing to
151 * After a new SQ head value was read by the application this
152 * counter includes all submissions that were dropped reaching
153 * the new SQ head (and possibly more).
159 * Written by the kernel, shouldn't be modified by the
162 * The application needs a full memory barrier before checking
163 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
169 * Written by the application, shouldn't be modified by the
174 * Number of completion events lost because the queue was full;
175 * this should be avoided by the application by making sure
176 * there are not more requests pending than there is space in
177 * the completion queue.
179 * Written by the kernel, shouldn't be modified by the
180 * application (i.e. get number of "new events" by comparing to
183 * As completion events come in out of order this counter is not
184 * ordered with any other data.
188 * Ring buffer of completion events.
190 * The kernel writes completion events fresh every time they are
191 * produced, so the application is allowed to modify pending
194 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
197 enum io_uring_cmd_flags
{
198 IO_URING_F_NONBLOCK
= 1,
199 IO_URING_F_COMPLETE_DEFER
= 2,
202 struct io_mapped_ubuf
{
205 unsigned int nr_bvecs
;
206 unsigned long acct_pages
;
207 struct bio_vec bvec
[];
212 struct io_overflow_cqe
{
213 struct io_uring_cqe cqe
;
214 struct list_head list
;
217 struct io_fixed_file
{
218 /* file * with additional FFS_* flags */
219 unsigned long file_ptr
;
223 struct list_head list
;
228 struct io_mapped_ubuf
*buf
;
232 struct io_file_table
{
233 struct io_fixed_file
*files
;
236 struct io_rsrc_node
{
237 struct percpu_ref refs
;
238 struct list_head node
;
239 struct list_head rsrc_list
;
240 struct io_rsrc_data
*rsrc_data
;
241 struct llist_node llist
;
245 typedef void (rsrc_put_fn
)(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
);
247 struct io_rsrc_data
{
248 struct io_ring_ctx
*ctx
;
254 struct completion done
;
259 struct list_head list
;
265 struct io_restriction
{
266 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
267 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
268 u8 sqe_flags_allowed
;
269 u8 sqe_flags_required
;
274 IO_SQ_THREAD_SHOULD_STOP
= 0,
275 IO_SQ_THREAD_SHOULD_PARK
,
280 atomic_t park_pending
;
283 /* ctx's that are using this sqd */
284 struct list_head ctx_list
;
286 struct task_struct
*thread
;
287 struct wait_queue_head wait
;
289 unsigned sq_thread_idle
;
295 struct completion exited
;
298 #define IO_COMPL_BATCH 32
299 #define IO_REQ_CACHE_SIZE 32
300 #define IO_REQ_ALLOC_BATCH 8
302 struct io_submit_link
{
303 struct io_kiocb
*head
;
304 struct io_kiocb
*last
;
307 struct io_submit_state
{
308 struct blk_plug plug
;
309 struct io_submit_link link
;
312 * io_kiocb alloc cache
314 void *reqs
[IO_REQ_CACHE_SIZE
];
315 unsigned int free_reqs
;
320 * Batch completion logic
322 struct io_kiocb
*compl_reqs
[IO_COMPL_BATCH
];
323 unsigned int compl_nr
;
324 /* inline/task_work completion list, under ->uring_lock */
325 struct list_head free_list
;
327 unsigned int ios_left
;
331 /* const or read-mostly hot data */
333 struct percpu_ref refs
;
335 struct io_rings
*rings
;
337 unsigned int compat
: 1;
338 unsigned int drain_next
: 1;
339 unsigned int eventfd_async
: 1;
340 unsigned int restricted
: 1;
341 unsigned int off_timeout_used
: 1;
342 unsigned int drain_active
: 1;
343 } ____cacheline_aligned_in_smp
;
345 /* submission data */
347 struct mutex uring_lock
;
350 * Ring buffer of indices into array of io_uring_sqe, which is
351 * mmapped by the application using the IORING_OFF_SQES offset.
353 * This indirection could e.g. be used to assign fixed
354 * io_uring_sqe entries to operations and only submit them to
355 * the queue when needed.
357 * The kernel modifies neither the indices array nor the entries
361 struct io_uring_sqe
*sq_sqes
;
362 unsigned cached_sq_head
;
364 struct list_head defer_list
;
367 * Fixed resources fast path, should be accessed only under
368 * uring_lock, and updated through io_uring_register(2)
370 struct io_rsrc_node
*rsrc_node
;
371 struct io_file_table file_table
;
372 unsigned nr_user_files
;
373 unsigned nr_user_bufs
;
374 struct io_mapped_ubuf
**user_bufs
;
376 struct io_submit_state submit_state
;
377 struct list_head timeout_list
;
378 struct list_head ltimeout_list
;
379 struct list_head cq_overflow_list
;
380 struct xarray io_buffers
;
381 struct xarray personalities
;
383 unsigned sq_thread_idle
;
384 } ____cacheline_aligned_in_smp
;
386 /* IRQ completion list, under ->completion_lock */
387 struct list_head locked_free_list
;
388 unsigned int locked_free_nr
;
390 const struct cred
*sq_creds
; /* cred used for __io_sq_thread() */
391 struct io_sq_data
*sq_data
; /* if using sq thread polling */
393 struct wait_queue_head sqo_sq_wait
;
394 struct list_head sqd_list
;
396 unsigned long check_cq_overflow
;
399 unsigned cached_cq_tail
;
401 struct eventfd_ctx
*cq_ev_fd
;
402 struct wait_queue_head poll_wait
;
403 struct wait_queue_head cq_wait
;
405 atomic_t cq_timeouts
;
406 unsigned cq_last_tm_flush
;
407 } ____cacheline_aligned_in_smp
;
410 spinlock_t completion_lock
;
412 spinlock_t timeout_lock
;
415 * ->iopoll_list is protected by the ctx->uring_lock for
416 * io_uring instances that don't use IORING_SETUP_SQPOLL.
417 * For SQPOLL, only the single threaded io_sq_thread() will
418 * manipulate the list, hence no extra locking is needed there.
420 struct list_head iopoll_list
;
421 struct hlist_head
*cancel_hash
;
422 unsigned cancel_hash_bits
;
423 bool poll_multi_queue
;
424 } ____cacheline_aligned_in_smp
;
426 struct io_restriction restrictions
;
428 /* slow path rsrc auxilary data, used by update/register */
430 struct io_rsrc_node
*rsrc_backup_node
;
431 struct io_mapped_ubuf
*dummy_ubuf
;
432 struct io_rsrc_data
*file_data
;
433 struct io_rsrc_data
*buf_data
;
435 struct delayed_work rsrc_put_work
;
436 struct llist_head rsrc_put_llist
;
437 struct list_head rsrc_ref_list
;
438 spinlock_t rsrc_ref_lock
;
441 /* Keep this last, we don't need it for the fast path */
443 #if defined(CONFIG_UNIX)
444 struct socket
*ring_sock
;
446 /* hashed buffered write serialization */
447 struct io_wq_hash
*hash_map
;
449 /* Only used for accounting purposes */
450 struct user_struct
*user
;
451 struct mm_struct
*mm_account
;
453 /* ctx exit and cancelation */
454 struct llist_head fallback_llist
;
455 struct delayed_work fallback_work
;
456 struct work_struct exit_work
;
457 struct list_head tctx_list
;
458 struct completion ref_comp
;
460 bool iowq_limits_set
;
464 struct io_uring_task
{
465 /* submission side */
468 struct wait_queue_head wait
;
469 const struct io_ring_ctx
*last
;
471 struct percpu_counter inflight
;
472 atomic_t inflight_tracked
;
475 spinlock_t task_lock
;
476 struct io_wq_work_list task_list
;
477 struct callback_head task_work
;
482 * First field must be the file pointer in all the
483 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
485 struct io_poll_iocb
{
487 struct wait_queue_head
*head
;
491 struct wait_queue_entry wait
;
494 struct io_poll_update
{
500 bool update_user_data
;
509 struct io_timeout_data
{
510 struct io_kiocb
*req
;
511 struct hrtimer timer
;
512 struct timespec64 ts
;
513 enum hrtimer_mode mode
;
519 struct sockaddr __user
*addr
;
520 int __user
*addr_len
;
523 unsigned long nofile
;
543 struct list_head list
;
544 /* head of the link, used by linked timeouts only */
545 struct io_kiocb
*head
;
546 /* for linked completions */
547 struct io_kiocb
*prev
;
550 struct io_timeout_rem
{
555 struct timespec64 ts
;
561 /* NOTE: kiocb has the file as the first member, so don't do it here */
569 struct sockaddr __user
*addr
;
576 struct compat_msghdr __user
*umsg_compat
;
577 struct user_msghdr __user
*umsg
;
583 struct io_buffer
*kbuf
;
590 struct filename
*filename
;
592 unsigned long nofile
;
595 struct io_rsrc_update
{
621 struct epoll_event event
;
625 struct file
*file_out
;
626 struct file
*file_in
;
633 struct io_provide_buf
{
647 const char __user
*filename
;
648 struct statx __user
*buffer
;
660 struct filename
*oldpath
;
661 struct filename
*newpath
;
669 struct filename
*filename
;
676 struct filename
*filename
;
682 struct filename
*oldpath
;
683 struct filename
*newpath
;
690 struct filename
*oldpath
;
691 struct filename
*newpath
;
695 struct io_completion
{
700 struct io_async_connect
{
701 struct sockaddr_storage address
;
704 struct io_async_msghdr
{
705 struct iovec fast_iov
[UIO_FASTIOV
];
706 /* points to an allocated iov, if NULL we use fast_iov instead */
707 struct iovec
*free_iov
;
708 struct sockaddr __user
*uaddr
;
710 struct sockaddr_storage addr
;
714 struct iovec fast_iov
[UIO_FASTIOV
];
715 const struct iovec
*free_iovec
;
716 struct iov_iter iter
;
717 struct iov_iter_state iter_state
;
719 struct wait_page_queue wpq
;
723 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
724 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
725 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
726 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
727 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
728 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
730 /* first byte is taken by user flags, shift it to not overlap */
735 REQ_F_LINK_TIMEOUT_BIT
,
736 REQ_F_NEED_CLEANUP_BIT
,
738 REQ_F_BUFFER_SELECTED_BIT
,
739 REQ_F_COMPLETE_INLINE_BIT
,
743 REQ_F_ARM_LTIMEOUT_BIT
,
744 /* keep async read/write and isreg together and in order */
745 REQ_F_NOWAIT_READ_BIT
,
746 REQ_F_NOWAIT_WRITE_BIT
,
749 /* not a real bit, just to check we're not overflowing the space */
755 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
756 /* drain existing IO first */
757 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
759 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
760 /* doesn't sever on completion < 0 */
761 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
763 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
764 /* IOSQE_BUFFER_SELECT */
765 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
767 /* fail rest of links */
768 REQ_F_FAIL
= BIT(REQ_F_FAIL_BIT
),
769 /* on inflight list, should be cancelled and waited on exit reliably */
770 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
771 /* read/write uses file position */
772 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
773 /* must not punt to workers */
774 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
775 /* has or had linked timeout */
776 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
778 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
779 /* already went through poll handler */
780 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
781 /* buffer already selected */
782 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
783 /* completion is deferred through io_comp_state */
784 REQ_F_COMPLETE_INLINE
= BIT(REQ_F_COMPLETE_INLINE_BIT
),
785 /* caller should reissue async */
786 REQ_F_REISSUE
= BIT(REQ_F_REISSUE_BIT
),
787 /* supports async reads */
788 REQ_F_NOWAIT_READ
= BIT(REQ_F_NOWAIT_READ_BIT
),
789 /* supports async writes */
790 REQ_F_NOWAIT_WRITE
= BIT(REQ_F_NOWAIT_WRITE_BIT
),
792 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
793 /* has creds assigned */
794 REQ_F_CREDS
= BIT(REQ_F_CREDS_BIT
),
795 /* skip refcounting if not set */
796 REQ_F_REFCOUNT
= BIT(REQ_F_REFCOUNT_BIT
),
797 /* there is a linked timeout that has to be armed */
798 REQ_F_ARM_LTIMEOUT
= BIT(REQ_F_ARM_LTIMEOUT_BIT
),
802 struct io_poll_iocb poll
;
803 struct io_poll_iocb
*double_poll
;
806 typedef void (*io_req_tw_func_t
)(struct io_kiocb
*req
, bool *locked
);
808 struct io_task_work
{
810 struct io_wq_work_node node
;
811 struct llist_node fallback_node
;
813 io_req_tw_func_t func
;
817 IORING_RSRC_FILE
= 0,
818 IORING_RSRC_BUFFER
= 1,
822 * NOTE! Each of the iocb union members has the file pointer
823 * as the first entry in their struct definition. So you can
824 * access the file pointer through any of the sub-structs,
825 * or directly as just 'ki_filp' in this struct.
831 struct io_poll_iocb poll
;
832 struct io_poll_update poll_update
;
833 struct io_accept accept
;
835 struct io_cancel cancel
;
836 struct io_timeout timeout
;
837 struct io_timeout_rem timeout_rem
;
838 struct io_connect connect
;
839 struct io_sr_msg sr_msg
;
841 struct io_close close
;
842 struct io_rsrc_update rsrc_update
;
843 struct io_fadvise fadvise
;
844 struct io_madvise madvise
;
845 struct io_epoll epoll
;
846 struct io_splice splice
;
847 struct io_provide_buf pbuf
;
848 struct io_statx statx
;
849 struct io_shutdown shutdown
;
850 struct io_rename rename
;
851 struct io_unlink unlink
;
852 struct io_mkdir mkdir
;
853 struct io_symlink symlink
;
854 struct io_hardlink hardlink
;
855 /* use only after cleaning per-op data, see io_clean_op() */
856 struct io_completion
compl;
859 /* opcode allocated if it needs to store data for async defer */
862 /* polled IO has completed */
868 struct io_ring_ctx
*ctx
;
871 struct task_struct
*task
;
874 struct io_kiocb
*link
;
875 struct percpu_ref
*fixed_rsrc_refs
;
877 /* used with ctx->iopoll_list with reads/writes */
878 struct list_head inflight_entry
;
879 struct io_task_work io_task_work
;
880 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
881 struct hlist_node hash_node
;
882 struct async_poll
*apoll
;
883 struct io_wq_work work
;
884 const struct cred
*creds
;
886 /* store used ubuf, so we can prevent reloading */
887 struct io_mapped_ubuf
*imu
;
890 struct io_tctx_node
{
891 struct list_head ctx_node
;
892 struct task_struct
*task
;
893 struct io_ring_ctx
*ctx
;
896 struct io_defer_entry
{
897 struct list_head list
;
898 struct io_kiocb
*req
;
903 /* needs req->file assigned */
904 unsigned needs_file
: 1;
905 /* hash wq insertion if file is a regular file */
906 unsigned hash_reg_file
: 1;
907 /* unbound wq insertion if file is a non-regular file */
908 unsigned unbound_nonreg_file
: 1;
909 /* opcode is not supported by this kernel */
910 unsigned not_supported
: 1;
911 /* set if opcode supports polled "wait" */
913 unsigned pollout
: 1;
914 /* op supports buffer selection */
915 unsigned buffer_select
: 1;
916 /* do prep async if is going to be punted */
917 unsigned needs_async_setup
: 1;
918 /* should block plug */
920 /* size of async data needed, if any */
921 unsigned short async_size
;
924 static const struct io_op_def io_op_defs
[] = {
925 [IORING_OP_NOP
] = {},
926 [IORING_OP_READV
] = {
928 .unbound_nonreg_file
= 1,
931 .needs_async_setup
= 1,
933 .async_size
= sizeof(struct io_async_rw
),
935 [IORING_OP_WRITEV
] = {
938 .unbound_nonreg_file
= 1,
940 .needs_async_setup
= 1,
942 .async_size
= sizeof(struct io_async_rw
),
944 [IORING_OP_FSYNC
] = {
947 [IORING_OP_READ_FIXED
] = {
949 .unbound_nonreg_file
= 1,
952 .async_size
= sizeof(struct io_async_rw
),
954 [IORING_OP_WRITE_FIXED
] = {
957 .unbound_nonreg_file
= 1,
960 .async_size
= sizeof(struct io_async_rw
),
962 [IORING_OP_POLL_ADD
] = {
964 .unbound_nonreg_file
= 1,
966 [IORING_OP_POLL_REMOVE
] = {},
967 [IORING_OP_SYNC_FILE_RANGE
] = {
970 [IORING_OP_SENDMSG
] = {
972 .unbound_nonreg_file
= 1,
974 .needs_async_setup
= 1,
975 .async_size
= sizeof(struct io_async_msghdr
),
977 [IORING_OP_RECVMSG
] = {
979 .unbound_nonreg_file
= 1,
982 .needs_async_setup
= 1,
983 .async_size
= sizeof(struct io_async_msghdr
),
985 [IORING_OP_TIMEOUT
] = {
986 .async_size
= sizeof(struct io_timeout_data
),
988 [IORING_OP_TIMEOUT_REMOVE
] = {
989 /* used by timeout updates' prep() */
991 [IORING_OP_ACCEPT
] = {
993 .unbound_nonreg_file
= 1,
996 [IORING_OP_ASYNC_CANCEL
] = {},
997 [IORING_OP_LINK_TIMEOUT
] = {
998 .async_size
= sizeof(struct io_timeout_data
),
1000 [IORING_OP_CONNECT
] = {
1002 .unbound_nonreg_file
= 1,
1004 .needs_async_setup
= 1,
1005 .async_size
= sizeof(struct io_async_connect
),
1007 [IORING_OP_FALLOCATE
] = {
1010 [IORING_OP_OPENAT
] = {},
1011 [IORING_OP_CLOSE
] = {},
1012 [IORING_OP_FILES_UPDATE
] = {},
1013 [IORING_OP_STATX
] = {},
1014 [IORING_OP_READ
] = {
1016 .unbound_nonreg_file
= 1,
1020 .async_size
= sizeof(struct io_async_rw
),
1022 [IORING_OP_WRITE
] = {
1025 .unbound_nonreg_file
= 1,
1028 .async_size
= sizeof(struct io_async_rw
),
1030 [IORING_OP_FADVISE
] = {
1033 [IORING_OP_MADVISE
] = {},
1034 [IORING_OP_SEND
] = {
1036 .unbound_nonreg_file
= 1,
1039 [IORING_OP_RECV
] = {
1041 .unbound_nonreg_file
= 1,
1045 [IORING_OP_OPENAT2
] = {
1047 [IORING_OP_EPOLL_CTL
] = {
1048 .unbound_nonreg_file
= 1,
1050 [IORING_OP_SPLICE
] = {
1053 .unbound_nonreg_file
= 1,
1055 [IORING_OP_PROVIDE_BUFFERS
] = {},
1056 [IORING_OP_REMOVE_BUFFERS
] = {},
1060 .unbound_nonreg_file
= 1,
1062 [IORING_OP_SHUTDOWN
] = {
1065 [IORING_OP_RENAMEAT
] = {},
1066 [IORING_OP_UNLINKAT
] = {},
1067 [IORING_OP_MKDIRAT
] = {},
1068 [IORING_OP_SYMLINKAT
] = {},
1069 [IORING_OP_LINKAT
] = {},
1072 /* requests with any of those set should undergo io_disarm_next() */
1073 #define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
1075 static bool io_disarm_next(struct io_kiocb
*req
);
1076 static void io_uring_del_tctx_node(unsigned long index
);
1077 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
1078 struct task_struct
*task
,
1080 static void io_uring_cancel_generic(bool cancel_all
, struct io_sq_data
*sqd
);
1082 static bool io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1083 long res
, unsigned int cflags
);
1084 static void io_put_req(struct io_kiocb
*req
);
1085 static void io_put_req_deferred(struct io_kiocb
*req
);
1086 static void io_dismantle_req(struct io_kiocb
*req
);
1087 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1088 static int __io_register_rsrc_update(struct io_ring_ctx
*ctx
, unsigned type
,
1089 struct io_uring_rsrc_update2
*up
,
1091 static void io_clean_op(struct io_kiocb
*req
);
1092 static struct file
*io_file_get(struct io_ring_ctx
*ctx
,
1093 struct io_kiocb
*req
, int fd
, bool fixed
);
1094 static void __io_queue_sqe(struct io_kiocb
*req
);
1095 static void io_rsrc_put_work(struct work_struct
*work
);
1097 static void io_req_task_queue(struct io_kiocb
*req
);
1098 static void io_submit_flush_completions(struct io_ring_ctx
*ctx
);
1099 static int io_req_prep_async(struct io_kiocb
*req
);
1101 static int io_install_fixed_file(struct io_kiocb
*req
, struct file
*file
,
1102 unsigned int issue_flags
, u32 slot_index
);
1103 static int io_close_fixed(struct io_kiocb
*req
, unsigned int issue_flags
);
1105 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
);
1107 static struct kmem_cache
*req_cachep
;
1109 static const struct file_operations io_uring_fops
;
1111 struct sock
*io_uring_get_socket(struct file
*file
)
1113 #if defined(CONFIG_UNIX)
1114 if (file
->f_op
== &io_uring_fops
) {
1115 struct io_ring_ctx
*ctx
= file
->private_data
;
1117 return ctx
->ring_sock
->sk
;
1122 EXPORT_SYMBOL(io_uring_get_socket
);
1124 static inline void io_tw_lock(struct io_ring_ctx
*ctx
, bool *locked
)
1127 mutex_lock(&ctx
->uring_lock
);
1132 #define io_for_each_link(pos, head) \
1133 for (pos = (head); pos; pos = pos->link)
1136 * Shamelessly stolen from the mm implementation of page reference checking,
1137 * see commit f958d7b528b1 for details.
1139 #define req_ref_zero_or_close_to_overflow(req) \
1140 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1142 static inline bool req_ref_inc_not_zero(struct io_kiocb
*req
)
1144 WARN_ON_ONCE(!(req
->flags
& REQ_F_REFCOUNT
));
1145 return atomic_inc_not_zero(&req
->refs
);
1148 static inline bool req_ref_put_and_test(struct io_kiocb
*req
)
1150 if (likely(!(req
->flags
& REQ_F_REFCOUNT
)))
1153 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1154 return atomic_dec_and_test(&req
->refs
);
1157 static inline void req_ref_put(struct io_kiocb
*req
)
1159 WARN_ON_ONCE(!(req
->flags
& REQ_F_REFCOUNT
));
1160 WARN_ON_ONCE(req_ref_put_and_test(req
));
1163 static inline void req_ref_get(struct io_kiocb
*req
)
1165 WARN_ON_ONCE(!(req
->flags
& REQ_F_REFCOUNT
));
1166 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1167 atomic_inc(&req
->refs
);
1170 static inline void __io_req_set_refcount(struct io_kiocb
*req
, int nr
)
1172 if (!(req
->flags
& REQ_F_REFCOUNT
)) {
1173 req
->flags
|= REQ_F_REFCOUNT
;
1174 atomic_set(&req
->refs
, nr
);
1178 static inline void io_req_set_refcount(struct io_kiocb
*req
)
1180 __io_req_set_refcount(req
, 1);
1183 static inline void io_req_set_rsrc_node(struct io_kiocb
*req
)
1185 struct io_ring_ctx
*ctx
= req
->ctx
;
1187 if (!req
->fixed_rsrc_refs
) {
1188 req
->fixed_rsrc_refs
= &ctx
->rsrc_node
->refs
;
1189 percpu_ref_get(req
->fixed_rsrc_refs
);
1193 static void io_refs_resurrect(struct percpu_ref
*ref
, struct completion
*compl)
1195 bool got
= percpu_ref_tryget(ref
);
1197 /* already at zero, wait for ->release() */
1199 wait_for_completion(compl);
1200 percpu_ref_resurrect(ref
);
1202 percpu_ref_put(ref
);
1205 static bool io_match_task(struct io_kiocb
*head
, struct task_struct
*task
,
1208 struct io_kiocb
*req
;
1210 if (task
&& head
->task
!= task
)
1215 io_for_each_link(req
, head
) {
1216 if (req
->flags
& REQ_F_INFLIGHT
)
1222 static inline void req_set_fail(struct io_kiocb
*req
)
1224 req
->flags
|= REQ_F_FAIL
;
1227 static inline void req_fail_link_node(struct io_kiocb
*req
, int res
)
1233 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1235 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1237 complete(&ctx
->ref_comp
);
1240 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1242 return !req
->timeout
.off
;
1245 static void io_fallback_req_func(struct work_struct
*work
)
1247 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
1248 fallback_work
.work
);
1249 struct llist_node
*node
= llist_del_all(&ctx
->fallback_llist
);
1250 struct io_kiocb
*req
, *tmp
;
1251 bool locked
= false;
1253 percpu_ref_get(&ctx
->refs
);
1254 llist_for_each_entry_safe(req
, tmp
, node
, io_task_work
.fallback_node
)
1255 req
->io_task_work
.func(req
, &locked
);
1258 if (ctx
->submit_state
.compl_nr
)
1259 io_submit_flush_completions(ctx
);
1260 mutex_unlock(&ctx
->uring_lock
);
1262 percpu_ref_put(&ctx
->refs
);
1266 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1268 struct io_ring_ctx
*ctx
;
1271 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1276 * Use 5 bits less than the max cq entries, that should give us around
1277 * 32 entries per hash list if totally full and uniformly spread.
1279 hash_bits
= ilog2(p
->cq_entries
);
1283 ctx
->cancel_hash_bits
= hash_bits
;
1284 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1286 if (!ctx
->cancel_hash
)
1288 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1290 ctx
->dummy_ubuf
= kzalloc(sizeof(*ctx
->dummy_ubuf
), GFP_KERNEL
);
1291 if (!ctx
->dummy_ubuf
)
1293 /* set invalid range, so io_import_fixed() fails meeting it */
1294 ctx
->dummy_ubuf
->ubuf
= -1UL;
1296 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1297 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1300 ctx
->flags
= p
->flags
;
1301 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1302 INIT_LIST_HEAD(&ctx
->sqd_list
);
1303 init_waitqueue_head(&ctx
->poll_wait
);
1304 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1305 init_completion(&ctx
->ref_comp
);
1306 xa_init_flags(&ctx
->io_buffers
, XA_FLAGS_ALLOC1
);
1307 xa_init_flags(&ctx
->personalities
, XA_FLAGS_ALLOC1
);
1308 mutex_init(&ctx
->uring_lock
);
1309 init_waitqueue_head(&ctx
->cq_wait
);
1310 spin_lock_init(&ctx
->completion_lock
);
1311 spin_lock_init(&ctx
->timeout_lock
);
1312 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1313 INIT_LIST_HEAD(&ctx
->defer_list
);
1314 INIT_LIST_HEAD(&ctx
->timeout_list
);
1315 INIT_LIST_HEAD(&ctx
->ltimeout_list
);
1316 spin_lock_init(&ctx
->rsrc_ref_lock
);
1317 INIT_LIST_HEAD(&ctx
->rsrc_ref_list
);
1318 INIT_DELAYED_WORK(&ctx
->rsrc_put_work
, io_rsrc_put_work
);
1319 init_llist_head(&ctx
->rsrc_put_llist
);
1320 INIT_LIST_HEAD(&ctx
->tctx_list
);
1321 INIT_LIST_HEAD(&ctx
->submit_state
.free_list
);
1322 INIT_LIST_HEAD(&ctx
->locked_free_list
);
1323 INIT_DELAYED_WORK(&ctx
->fallback_work
, io_fallback_req_func
);
1326 kfree(ctx
->dummy_ubuf
);
1327 kfree(ctx
->cancel_hash
);
1332 static void io_account_cq_overflow(struct io_ring_ctx
*ctx
)
1334 struct io_rings
*r
= ctx
->rings
;
1336 WRITE_ONCE(r
->cq_overflow
, READ_ONCE(r
->cq_overflow
) + 1);
1340 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1342 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1343 struct io_ring_ctx
*ctx
= req
->ctx
;
1345 return seq
+ READ_ONCE(ctx
->cq_extra
) != ctx
->cached_cq_tail
;
1351 #define FFS_ASYNC_READ 0x1UL
1352 #define FFS_ASYNC_WRITE 0x2UL
1354 #define FFS_ISREG 0x4UL
1356 #define FFS_ISREG 0x0UL
1358 #define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
1360 static inline bool io_req_ffs_set(struct io_kiocb
*req
)
1362 return IS_ENABLED(CONFIG_64BIT
) && (req
->flags
& REQ_F_FIXED_FILE
);
1365 static void io_req_track_inflight(struct io_kiocb
*req
)
1367 if (!(req
->flags
& REQ_F_INFLIGHT
)) {
1368 req
->flags
|= REQ_F_INFLIGHT
;
1369 atomic_inc(¤t
->io_uring
->inflight_tracked
);
1373 static struct io_kiocb
*__io_prep_linked_timeout(struct io_kiocb
*req
)
1375 if (WARN_ON_ONCE(!req
->link
))
1378 req
->flags
&= ~REQ_F_ARM_LTIMEOUT
;
1379 req
->flags
|= REQ_F_LINK_TIMEOUT
;
1381 /* linked timeouts should have two refs once prep'ed */
1382 io_req_set_refcount(req
);
1383 __io_req_set_refcount(req
->link
, 2);
1387 static inline struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
1389 if (likely(!(req
->flags
& REQ_F_ARM_LTIMEOUT
)))
1391 return __io_prep_linked_timeout(req
);
1394 static void io_prep_async_work(struct io_kiocb
*req
)
1396 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1397 struct io_ring_ctx
*ctx
= req
->ctx
;
1399 if (!(req
->flags
& REQ_F_CREDS
)) {
1400 req
->flags
|= REQ_F_CREDS
;
1401 req
->creds
= get_current_cred();
1404 req
->work
.list
.next
= NULL
;
1405 req
->work
.flags
= 0;
1406 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1407 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1409 if (req
->flags
& REQ_F_ISREG
) {
1410 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1411 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1412 } else if (!req
->file
|| !S_ISBLK(file_inode(req
->file
)->i_mode
)) {
1413 if (def
->unbound_nonreg_file
)
1414 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1417 switch (req
->opcode
) {
1418 case IORING_OP_SPLICE
:
1420 if (!S_ISREG(file_inode(req
->splice
.file_in
)->i_mode
))
1421 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1426 static void io_prep_async_link(struct io_kiocb
*req
)
1428 struct io_kiocb
*cur
;
1430 if (req
->flags
& REQ_F_LINK_TIMEOUT
) {
1431 struct io_ring_ctx
*ctx
= req
->ctx
;
1433 spin_lock(&ctx
->completion_lock
);
1434 io_for_each_link(cur
, req
)
1435 io_prep_async_work(cur
);
1436 spin_unlock(&ctx
->completion_lock
);
1438 io_for_each_link(cur
, req
)
1439 io_prep_async_work(cur
);
1443 static void io_queue_async_work(struct io_kiocb
*req
, bool *locked
)
1445 struct io_ring_ctx
*ctx
= req
->ctx
;
1446 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1447 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1449 /* must not take the lock, NULL it as a precaution */
1453 BUG_ON(!tctx
->io_wq
);
1455 /* init ->work of the whole link before punting */
1456 io_prep_async_link(req
);
1459 * Not expected to happen, but if we do have a bug where this _can_
1460 * happen, catch it here and ensure the request is marked as
1461 * canceled. That will make io-wq go through the usual work cancel
1462 * procedure rather than attempt to run this request (or create a new
1465 if (WARN_ON_ONCE(!same_thread_group(req
->task
, current
)))
1466 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1468 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1469 &req
->work
, req
->flags
);
1470 io_wq_enqueue(tctx
->io_wq
, &req
->work
);
1472 io_queue_linked_timeout(link
);
1475 static void io_kill_timeout(struct io_kiocb
*req
, int status
)
1476 __must_hold(&req
->ctx
->completion_lock
)
1477 __must_hold(&req
->ctx
->timeout_lock
)
1479 struct io_timeout_data
*io
= req
->async_data
;
1481 if (hrtimer_try_to_cancel(&io
->timer
) != -1) {
1484 atomic_set(&req
->ctx
->cq_timeouts
,
1485 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1486 list_del_init(&req
->timeout
.list
);
1487 io_cqring_fill_event(req
->ctx
, req
->user_data
, status
, 0);
1488 io_put_req_deferred(req
);
1492 static void io_queue_deferred(struct io_ring_ctx
*ctx
)
1494 while (!list_empty(&ctx
->defer_list
)) {
1495 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1496 struct io_defer_entry
, list
);
1498 if (req_need_defer(de
->req
, de
->seq
))
1500 list_del_init(&de
->list
);
1501 io_req_task_queue(de
->req
);
1506 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1507 __must_hold(&ctx
->completion_lock
)
1509 u32 seq
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
1511 spin_lock_irq(&ctx
->timeout_lock
);
1512 while (!list_empty(&ctx
->timeout_list
)) {
1513 u32 events_needed
, events_got
;
1514 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1515 struct io_kiocb
, timeout
.list
);
1517 if (io_is_timeout_noseq(req
))
1521 * Since seq can easily wrap around over time, subtract
1522 * the last seq at which timeouts were flushed before comparing.
1523 * Assuming not more than 2^31-1 events have happened since,
1524 * these subtractions won't have wrapped, so we can check if
1525 * target is in [last_seq, current_seq] by comparing the two.
1527 events_needed
= req
->timeout
.target_seq
- ctx
->cq_last_tm_flush
;
1528 events_got
= seq
- ctx
->cq_last_tm_flush
;
1529 if (events_got
< events_needed
)
1532 list_del_init(&req
->timeout
.list
);
1533 io_kill_timeout(req
, 0);
1535 ctx
->cq_last_tm_flush
= seq
;
1536 spin_unlock_irq(&ctx
->timeout_lock
);
1539 static void __io_commit_cqring_flush(struct io_ring_ctx
*ctx
)
1541 if (ctx
->off_timeout_used
)
1542 io_flush_timeouts(ctx
);
1543 if (ctx
->drain_active
)
1544 io_queue_deferred(ctx
);
1547 static inline void io_commit_cqring(struct io_ring_ctx
*ctx
)
1549 if (unlikely(ctx
->off_timeout_used
|| ctx
->drain_active
))
1550 __io_commit_cqring_flush(ctx
);
1551 /* order cqe stores with ring update */
1552 smp_store_release(&ctx
->rings
->cq
.tail
, ctx
->cached_cq_tail
);
1555 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1557 struct io_rings
*r
= ctx
->rings
;
1559 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== ctx
->sq_entries
;
1562 static inline unsigned int __io_cqring_events(struct io_ring_ctx
*ctx
)
1564 return ctx
->cached_cq_tail
- READ_ONCE(ctx
->rings
->cq
.head
);
1567 static inline struct io_uring_cqe
*io_get_cqe(struct io_ring_ctx
*ctx
)
1569 struct io_rings
*rings
= ctx
->rings
;
1570 unsigned tail
, mask
= ctx
->cq_entries
- 1;
1573 * writes to the cq entry need to come after reading head; the
1574 * control dependency is enough as we're using WRITE_ONCE to
1577 if (__io_cqring_events(ctx
) == ctx
->cq_entries
)
1580 tail
= ctx
->cached_cq_tail
++;
1581 return &rings
->cqes
[tail
& mask
];
1584 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1586 if (likely(!ctx
->cq_ev_fd
))
1588 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1590 return !ctx
->eventfd_async
|| io_wq_current_is_worker();
1594 * This should only get called when at least one event has been posted.
1595 * Some applications rely on the eventfd notification count only changing
1596 * IFF a new CQE has been added to the CQ ring. There's no depedency on
1597 * 1:1 relationship between how many times this function is called (and
1598 * hence the eventfd count) and number of CQEs posted to the CQ ring.
1600 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1603 * wake_up_all() may seem excessive, but io_wake_function() and
1604 * io_should_wake() handle the termination of the loop and only
1605 * wake as many waiters as we need to.
1607 if (wq_has_sleeper(&ctx
->cq_wait
))
1608 wake_up_all(&ctx
->cq_wait
);
1609 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1610 wake_up(&ctx
->sq_data
->wait
);
1611 if (io_should_trigger_evfd(ctx
))
1612 eventfd_signal(ctx
->cq_ev_fd
, 1);
1613 if (waitqueue_active(&ctx
->poll_wait
))
1614 wake_up_interruptible(&ctx
->poll_wait
);
1617 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx
*ctx
)
1619 /* see waitqueue_active() comment */
1622 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1623 if (waitqueue_active(&ctx
->cq_wait
))
1624 wake_up_all(&ctx
->cq_wait
);
1626 if (io_should_trigger_evfd(ctx
))
1627 eventfd_signal(ctx
->cq_ev_fd
, 1);
1628 if (waitqueue_active(&ctx
->poll_wait
))
1629 wake_up_interruptible(&ctx
->poll_wait
);
1632 /* Returns true if there are no backlogged entries after the flush */
1633 static bool __io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1635 bool all_flushed
, posted
;
1637 if (!force
&& __io_cqring_events(ctx
) == ctx
->cq_entries
)
1641 spin_lock(&ctx
->completion_lock
);
1642 while (!list_empty(&ctx
->cq_overflow_list
)) {
1643 struct io_uring_cqe
*cqe
= io_get_cqe(ctx
);
1644 struct io_overflow_cqe
*ocqe
;
1648 ocqe
= list_first_entry(&ctx
->cq_overflow_list
,
1649 struct io_overflow_cqe
, list
);
1651 memcpy(cqe
, &ocqe
->cqe
, sizeof(*cqe
));
1653 io_account_cq_overflow(ctx
);
1656 list_del(&ocqe
->list
);
1660 all_flushed
= list_empty(&ctx
->cq_overflow_list
);
1662 clear_bit(0, &ctx
->check_cq_overflow
);
1663 WRITE_ONCE(ctx
->rings
->sq_flags
,
1664 ctx
->rings
->sq_flags
& ~IORING_SQ_CQ_OVERFLOW
);
1668 io_commit_cqring(ctx
);
1669 spin_unlock(&ctx
->completion_lock
);
1671 io_cqring_ev_posted(ctx
);
1675 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
)
1679 if (test_bit(0, &ctx
->check_cq_overflow
)) {
1680 /* iopoll syncs against uring_lock, not completion_lock */
1681 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1682 mutex_lock(&ctx
->uring_lock
);
1683 ret
= __io_cqring_overflow_flush(ctx
, false);
1684 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1685 mutex_unlock(&ctx
->uring_lock
);
1691 /* must to be called somewhat shortly after putting a request */
1692 static inline void io_put_task(struct task_struct
*task
, int nr
)
1694 struct io_uring_task
*tctx
= task
->io_uring
;
1696 if (likely(task
== current
)) {
1697 tctx
->cached_refs
+= nr
;
1699 percpu_counter_sub(&tctx
->inflight
, nr
);
1700 if (unlikely(atomic_read(&tctx
->in_idle
)))
1701 wake_up(&tctx
->wait
);
1702 put_task_struct_many(task
, nr
);
1706 static void io_task_refs_refill(struct io_uring_task
*tctx
)
1708 unsigned int refill
= -tctx
->cached_refs
+ IO_TCTX_REFS_CACHE_NR
;
1710 percpu_counter_add(&tctx
->inflight
, refill
);
1711 refcount_add(refill
, ¤t
->usage
);
1712 tctx
->cached_refs
+= refill
;
1715 static inline void io_get_task_refs(int nr
)
1717 struct io_uring_task
*tctx
= current
->io_uring
;
1719 tctx
->cached_refs
-= nr
;
1720 if (unlikely(tctx
->cached_refs
< 0))
1721 io_task_refs_refill(tctx
);
1724 static bool io_cqring_event_overflow(struct io_ring_ctx
*ctx
, u64 user_data
,
1725 long res
, unsigned int cflags
)
1727 struct io_overflow_cqe
*ocqe
;
1729 ocqe
= kmalloc(sizeof(*ocqe
), GFP_ATOMIC
| __GFP_ACCOUNT
);
1732 * If we're in ring overflow flush mode, or in task cancel mode,
1733 * or cannot allocate an overflow entry, then we need to drop it
1736 io_account_cq_overflow(ctx
);
1739 if (list_empty(&ctx
->cq_overflow_list
)) {
1740 set_bit(0, &ctx
->check_cq_overflow
);
1741 WRITE_ONCE(ctx
->rings
->sq_flags
,
1742 ctx
->rings
->sq_flags
| IORING_SQ_CQ_OVERFLOW
);
1745 ocqe
->cqe
.user_data
= user_data
;
1746 ocqe
->cqe
.res
= res
;
1747 ocqe
->cqe
.flags
= cflags
;
1748 list_add_tail(&ocqe
->list
, &ctx
->cq_overflow_list
);
1752 static inline bool __io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1753 long res
, unsigned int cflags
)
1755 struct io_uring_cqe
*cqe
;
1757 trace_io_uring_complete(ctx
, user_data
, res
, cflags
);
1760 * If we can't get a cq entry, userspace overflowed the
1761 * submission (by quite a lot). Increment the overflow count in
1764 cqe
= io_get_cqe(ctx
);
1766 WRITE_ONCE(cqe
->user_data
, user_data
);
1767 WRITE_ONCE(cqe
->res
, res
);
1768 WRITE_ONCE(cqe
->flags
, cflags
);
1771 return io_cqring_event_overflow(ctx
, user_data
, res
, cflags
);
1774 /* not as hot to bloat with inlining */
1775 static noinline
bool io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1776 long res
, unsigned int cflags
)
1778 return __io_cqring_fill_event(ctx
, user_data
, res
, cflags
);
1781 static void io_req_complete_post(struct io_kiocb
*req
, long res
,
1782 unsigned int cflags
)
1784 struct io_ring_ctx
*ctx
= req
->ctx
;
1786 spin_lock(&ctx
->completion_lock
);
1787 __io_cqring_fill_event(ctx
, req
->user_data
, res
, cflags
);
1789 * If we're the last reference to this request, add to our locked
1792 if (req_ref_put_and_test(req
)) {
1793 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
1794 if (req
->flags
& IO_DISARM_MASK
)
1795 io_disarm_next(req
);
1797 io_req_task_queue(req
->link
);
1801 io_dismantle_req(req
);
1802 io_put_task(req
->task
, 1);
1803 list_add(&req
->inflight_entry
, &ctx
->locked_free_list
);
1804 ctx
->locked_free_nr
++;
1806 if (!percpu_ref_tryget(&ctx
->refs
))
1809 io_commit_cqring(ctx
);
1810 spin_unlock(&ctx
->completion_lock
);
1813 io_cqring_ev_posted(ctx
);
1814 percpu_ref_put(&ctx
->refs
);
1818 static inline bool io_req_needs_clean(struct io_kiocb
*req
)
1820 return req
->flags
& IO_REQ_CLEAN_FLAGS
;
1823 static void io_req_complete_state(struct io_kiocb
*req
, long res
,
1824 unsigned int cflags
)
1826 if (io_req_needs_clean(req
))
1829 req
->compl.cflags
= cflags
;
1830 req
->flags
|= REQ_F_COMPLETE_INLINE
;
1833 static inline void __io_req_complete(struct io_kiocb
*req
, unsigned issue_flags
,
1834 long res
, unsigned cflags
)
1836 if (issue_flags
& IO_URING_F_COMPLETE_DEFER
)
1837 io_req_complete_state(req
, res
, cflags
);
1839 io_req_complete_post(req
, res
, cflags
);
1842 static inline void io_req_complete(struct io_kiocb
*req
, long res
)
1844 __io_req_complete(req
, 0, res
, 0);
1847 static void io_req_complete_failed(struct io_kiocb
*req
, long res
)
1850 io_req_complete_post(req
, res
, 0);
1853 static void io_req_complete_fail_submit(struct io_kiocb
*req
)
1856 * We don't submit, fail them all, for that replace hardlinks with
1857 * normal links. Extra REQ_F_LINK is tolerated.
1859 req
->flags
&= ~REQ_F_HARDLINK
;
1860 req
->flags
|= REQ_F_LINK
;
1861 io_req_complete_failed(req
, req
->result
);
1865 * Don't initialise the fields below on every allocation, but do that in
1866 * advance and keep them valid across allocations.
1868 static void io_preinit_req(struct io_kiocb
*req
, struct io_ring_ctx
*ctx
)
1872 req
->async_data
= NULL
;
1873 /* not necessary, but safer to zero */
1877 static void io_flush_cached_locked_reqs(struct io_ring_ctx
*ctx
,
1878 struct io_submit_state
*state
)
1880 spin_lock(&ctx
->completion_lock
);
1881 list_splice_init(&ctx
->locked_free_list
, &state
->free_list
);
1882 ctx
->locked_free_nr
= 0;
1883 spin_unlock(&ctx
->completion_lock
);
1886 /* Returns true IFF there are requests in the cache */
1887 static bool io_flush_cached_reqs(struct io_ring_ctx
*ctx
)
1889 struct io_submit_state
*state
= &ctx
->submit_state
;
1893 * If we have more than a batch's worth of requests in our IRQ side
1894 * locked cache, grab the lock and move them over to our submission
1897 if (READ_ONCE(ctx
->locked_free_nr
) > IO_COMPL_BATCH
)
1898 io_flush_cached_locked_reqs(ctx
, state
);
1900 nr
= state
->free_reqs
;
1901 while (!list_empty(&state
->free_list
)) {
1902 struct io_kiocb
*req
= list_first_entry(&state
->free_list
,
1903 struct io_kiocb
, inflight_entry
);
1905 list_del(&req
->inflight_entry
);
1906 state
->reqs
[nr
++] = req
;
1907 if (nr
== ARRAY_SIZE(state
->reqs
))
1911 state
->free_reqs
= nr
;
1916 * A request might get retired back into the request caches even before opcode
1917 * handlers and io_issue_sqe() are done with it, e.g. inline completion path.
1918 * Because of that, io_alloc_req() should be called only under ->uring_lock
1919 * and with extra caution to not get a request that is still worked on.
1921 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
)
1922 __must_hold(&ctx
->uring_lock
)
1924 struct io_submit_state
*state
= &ctx
->submit_state
;
1925 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1928 BUILD_BUG_ON(ARRAY_SIZE(state
->reqs
) < IO_REQ_ALLOC_BATCH
);
1930 if (likely(state
->free_reqs
|| io_flush_cached_reqs(ctx
)))
1933 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, IO_REQ_ALLOC_BATCH
,
1937 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1938 * retry single alloc to be on the safe side.
1940 if (unlikely(ret
<= 0)) {
1941 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1942 if (!state
->reqs
[0])
1947 for (i
= 0; i
< ret
; i
++)
1948 io_preinit_req(state
->reqs
[i
], ctx
);
1949 state
->free_reqs
= ret
;
1952 return state
->reqs
[state
->free_reqs
];
1955 static inline void io_put_file(struct file
*file
)
1961 static void io_dismantle_req(struct io_kiocb
*req
)
1963 unsigned int flags
= req
->flags
;
1965 if (io_req_needs_clean(req
))
1967 if (!(flags
& REQ_F_FIXED_FILE
))
1968 io_put_file(req
->file
);
1969 if (req
->fixed_rsrc_refs
)
1970 percpu_ref_put(req
->fixed_rsrc_refs
);
1971 if (req
->async_data
) {
1972 kfree(req
->async_data
);
1973 req
->async_data
= NULL
;
1977 static void __io_free_req(struct io_kiocb
*req
)
1979 struct io_ring_ctx
*ctx
= req
->ctx
;
1981 io_dismantle_req(req
);
1982 io_put_task(req
->task
, 1);
1984 spin_lock(&ctx
->completion_lock
);
1985 list_add(&req
->inflight_entry
, &ctx
->locked_free_list
);
1986 ctx
->locked_free_nr
++;
1987 spin_unlock(&ctx
->completion_lock
);
1989 percpu_ref_put(&ctx
->refs
);
1992 static inline void io_remove_next_linked(struct io_kiocb
*req
)
1994 struct io_kiocb
*nxt
= req
->link
;
1996 req
->link
= nxt
->link
;
2000 static bool io_kill_linked_timeout(struct io_kiocb
*req
)
2001 __must_hold(&req
->ctx
->completion_lock
)
2002 __must_hold(&req
->ctx
->timeout_lock
)
2004 struct io_kiocb
*link
= req
->link
;
2006 if (link
&& link
->opcode
== IORING_OP_LINK_TIMEOUT
) {
2007 struct io_timeout_data
*io
= link
->async_data
;
2009 io_remove_next_linked(req
);
2010 link
->timeout
.head
= NULL
;
2011 if (hrtimer_try_to_cancel(&io
->timer
) != -1) {
2012 list_del(&link
->timeout
.list
);
2013 io_cqring_fill_event(link
->ctx
, link
->user_data
,
2015 io_put_req_deferred(link
);
2022 static void io_fail_links(struct io_kiocb
*req
)
2023 __must_hold(&req
->ctx
->completion_lock
)
2025 struct io_kiocb
*nxt
, *link
= req
->link
;
2029 long res
= -ECANCELED
;
2031 if (link
->flags
& REQ_F_FAIL
)
2037 trace_io_uring_fail_link(req
, link
);
2038 io_cqring_fill_event(link
->ctx
, link
->user_data
, res
, 0);
2039 io_put_req_deferred(link
);
2044 static bool io_disarm_next(struct io_kiocb
*req
)
2045 __must_hold(&req
->ctx
->completion_lock
)
2047 bool posted
= false;
2049 if (req
->flags
& REQ_F_ARM_LTIMEOUT
) {
2050 struct io_kiocb
*link
= req
->link
;
2052 req
->flags
&= ~REQ_F_ARM_LTIMEOUT
;
2053 if (link
&& link
->opcode
== IORING_OP_LINK_TIMEOUT
) {
2054 io_remove_next_linked(req
);
2055 io_cqring_fill_event(link
->ctx
, link
->user_data
,
2057 io_put_req_deferred(link
);
2060 } else if (req
->flags
& REQ_F_LINK_TIMEOUT
) {
2061 struct io_ring_ctx
*ctx
= req
->ctx
;
2063 spin_lock_irq(&ctx
->timeout_lock
);
2064 posted
= io_kill_linked_timeout(req
);
2065 spin_unlock_irq(&ctx
->timeout_lock
);
2067 if (unlikely((req
->flags
& REQ_F_FAIL
) &&
2068 !(req
->flags
& REQ_F_HARDLINK
))) {
2069 posted
|= (req
->link
!= NULL
);
2075 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
2077 struct io_kiocb
*nxt
;
2080 * If LINK is set, we have dependent requests in this chain. If we
2081 * didn't fail this request, queue the first one up, moving any other
2082 * dependencies to the next request. In case of failure, fail the rest
2085 if (req
->flags
& IO_DISARM_MASK
) {
2086 struct io_ring_ctx
*ctx
= req
->ctx
;
2089 spin_lock(&ctx
->completion_lock
);
2090 posted
= io_disarm_next(req
);
2092 io_commit_cqring(req
->ctx
);
2093 spin_unlock(&ctx
->completion_lock
);
2095 io_cqring_ev_posted(ctx
);
2102 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
2104 if (likely(!(req
->flags
& (REQ_F_LINK
|REQ_F_HARDLINK
))))
2106 return __io_req_find_next(req
);
2109 static void ctx_flush_and_put(struct io_ring_ctx
*ctx
, bool *locked
)
2114 if (ctx
->submit_state
.compl_nr
)
2115 io_submit_flush_completions(ctx
);
2116 mutex_unlock(&ctx
->uring_lock
);
2119 percpu_ref_put(&ctx
->refs
);
2122 static void tctx_task_work(struct callback_head
*cb
)
2124 bool locked
= false;
2125 struct io_ring_ctx
*ctx
= NULL
;
2126 struct io_uring_task
*tctx
= container_of(cb
, struct io_uring_task
,
2130 struct io_wq_work_node
*node
;
2132 if (!tctx
->task_list
.first
&& locked
&& ctx
->submit_state
.compl_nr
)
2133 io_submit_flush_completions(ctx
);
2135 spin_lock_irq(&tctx
->task_lock
);
2136 node
= tctx
->task_list
.first
;
2137 INIT_WQ_LIST(&tctx
->task_list
);
2139 tctx
->task_running
= false;
2140 spin_unlock_irq(&tctx
->task_lock
);
2145 struct io_wq_work_node
*next
= node
->next
;
2146 struct io_kiocb
*req
= container_of(node
, struct io_kiocb
,
2149 if (req
->ctx
!= ctx
) {
2150 ctx_flush_and_put(ctx
, &locked
);
2152 /* if not contended, grab and improve batching */
2153 locked
= mutex_trylock(&ctx
->uring_lock
);
2154 percpu_ref_get(&ctx
->refs
);
2156 req
->io_task_work
.func(req
, &locked
);
2163 ctx_flush_and_put(ctx
, &locked
);
2166 static void io_req_task_work_add(struct io_kiocb
*req
)
2168 struct task_struct
*tsk
= req
->task
;
2169 struct io_uring_task
*tctx
= tsk
->io_uring
;
2170 enum task_work_notify_mode notify
;
2171 struct io_wq_work_node
*node
;
2172 unsigned long flags
;
2175 WARN_ON_ONCE(!tctx
);
2177 spin_lock_irqsave(&tctx
->task_lock
, flags
);
2178 wq_list_add_tail(&req
->io_task_work
.node
, &tctx
->task_list
);
2179 running
= tctx
->task_running
;
2181 tctx
->task_running
= true;
2182 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
2184 /* task_work already pending, we're done */
2189 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2190 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2191 * processing task_work. There's no reliable way to tell if TWA_RESUME
2194 notify
= (req
->ctx
->flags
& IORING_SETUP_SQPOLL
) ? TWA_NONE
: TWA_SIGNAL
;
2195 if (!task_work_add(tsk
, &tctx
->task_work
, notify
)) {
2196 wake_up_process(tsk
);
2200 spin_lock_irqsave(&tctx
->task_lock
, flags
);
2201 tctx
->task_running
= false;
2202 node
= tctx
->task_list
.first
;
2203 INIT_WQ_LIST(&tctx
->task_list
);
2204 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
2207 req
= container_of(node
, struct io_kiocb
, io_task_work
.node
);
2209 if (llist_add(&req
->io_task_work
.fallback_node
,
2210 &req
->ctx
->fallback_llist
))
2211 schedule_delayed_work(&req
->ctx
->fallback_work
, 1);
2215 static void io_req_task_cancel(struct io_kiocb
*req
, bool *locked
)
2217 struct io_ring_ctx
*ctx
= req
->ctx
;
2219 /* not needed for normal modes, but SQPOLL depends on it */
2220 io_tw_lock(ctx
, locked
);
2221 io_req_complete_failed(req
, req
->result
);
2224 static void io_req_task_submit(struct io_kiocb
*req
, bool *locked
)
2226 struct io_ring_ctx
*ctx
= req
->ctx
;
2228 io_tw_lock(ctx
, locked
);
2229 /* req->task == current here, checking PF_EXITING is safe */
2230 if (likely(!(req
->task
->flags
& PF_EXITING
)))
2231 __io_queue_sqe(req
);
2233 io_req_complete_failed(req
, -EFAULT
);
2236 static void io_req_task_queue_fail(struct io_kiocb
*req
, int ret
)
2239 req
->io_task_work
.func
= io_req_task_cancel
;
2240 io_req_task_work_add(req
);
2243 static void io_req_task_queue(struct io_kiocb
*req
)
2245 req
->io_task_work
.func
= io_req_task_submit
;
2246 io_req_task_work_add(req
);
2249 static void io_req_task_queue_reissue(struct io_kiocb
*req
)
2251 req
->io_task_work
.func
= io_queue_async_work
;
2252 io_req_task_work_add(req
);
2255 static inline void io_queue_next(struct io_kiocb
*req
)
2257 struct io_kiocb
*nxt
= io_req_find_next(req
);
2260 io_req_task_queue(nxt
);
2263 static void io_free_req(struct io_kiocb
*req
)
2269 static void io_free_req_work(struct io_kiocb
*req
, bool *locked
)
2275 struct task_struct
*task
;
2280 static inline void io_init_req_batch(struct req_batch
*rb
)
2287 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2288 struct req_batch
*rb
)
2291 percpu_ref_put_many(&ctx
->refs
, rb
->ctx_refs
);
2293 io_put_task(rb
->task
, rb
->task_refs
);
2296 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
,
2297 struct io_submit_state
*state
)
2300 io_dismantle_req(req
);
2302 if (req
->task
!= rb
->task
) {
2304 io_put_task(rb
->task
, rb
->task_refs
);
2305 rb
->task
= req
->task
;
2311 if (state
->free_reqs
!= ARRAY_SIZE(state
->reqs
))
2312 state
->reqs
[state
->free_reqs
++] = req
;
2314 list_add(&req
->inflight_entry
, &state
->free_list
);
2317 static void io_submit_flush_completions(struct io_ring_ctx
*ctx
)
2318 __must_hold(&ctx
->uring_lock
)
2320 struct io_submit_state
*state
= &ctx
->submit_state
;
2321 int i
, nr
= state
->compl_nr
;
2322 struct req_batch rb
;
2324 spin_lock(&ctx
->completion_lock
);
2325 for (i
= 0; i
< nr
; i
++) {
2326 struct io_kiocb
*req
= state
->compl_reqs
[i
];
2328 __io_cqring_fill_event(ctx
, req
->user_data
, req
->result
,
2331 io_commit_cqring(ctx
);
2332 spin_unlock(&ctx
->completion_lock
);
2333 io_cqring_ev_posted(ctx
);
2335 io_init_req_batch(&rb
);
2336 for (i
= 0; i
< nr
; i
++) {
2337 struct io_kiocb
*req
= state
->compl_reqs
[i
];
2339 if (req_ref_put_and_test(req
))
2340 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2343 io_req_free_batch_finish(ctx
, &rb
);
2344 state
->compl_nr
= 0;
2348 * Drop reference to request, return next in chain (if there is one) if this
2349 * was the last reference to this request.
2351 static inline struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2353 struct io_kiocb
*nxt
= NULL
;
2355 if (req_ref_put_and_test(req
)) {
2356 nxt
= io_req_find_next(req
);
2362 static inline void io_put_req(struct io_kiocb
*req
)
2364 if (req_ref_put_and_test(req
))
2368 static inline void io_put_req_deferred(struct io_kiocb
*req
)
2370 if (req_ref_put_and_test(req
)) {
2371 req
->io_task_work
.func
= io_free_req_work
;
2372 io_req_task_work_add(req
);
2376 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
)
2378 /* See comment at the top of this file */
2380 return __io_cqring_events(ctx
);
2383 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2385 struct io_rings
*rings
= ctx
->rings
;
2387 /* make sure SQ entry isn't read before tail */
2388 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2391 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2393 unsigned int cflags
;
2395 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2396 cflags
|= IORING_CQE_F_BUFFER
;
2397 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2402 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2404 struct io_buffer
*kbuf
;
2406 if (likely(!(req
->flags
& REQ_F_BUFFER_SELECTED
)))
2408 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2409 return io_put_kbuf(req
, kbuf
);
2412 static inline bool io_run_task_work(void)
2414 if (test_thread_flag(TIF_NOTIFY_SIGNAL
) || current
->task_works
) {
2415 __set_current_state(TASK_RUNNING
);
2416 tracehook_notify_signal();
2424 * Find and free completed poll iocbs
2426 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2427 struct list_head
*done
)
2429 struct req_batch rb
;
2430 struct io_kiocb
*req
;
2432 /* order with ->result store in io_complete_rw_iopoll() */
2435 io_init_req_batch(&rb
);
2436 while (!list_empty(done
)) {
2437 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2438 list_del(&req
->inflight_entry
);
2440 __io_cqring_fill_event(ctx
, req
->user_data
, req
->result
,
2441 io_put_rw_kbuf(req
));
2444 if (req_ref_put_and_test(req
))
2445 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2448 io_commit_cqring(ctx
);
2449 io_cqring_ev_posted_iopoll(ctx
);
2450 io_req_free_batch_finish(ctx
, &rb
);
2453 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2456 struct io_kiocb
*req
, *tmp
;
2461 * Only spin for completions if we don't have multiple devices hanging
2462 * off our complete list, and we're under the requested amount.
2464 spin
= !ctx
->poll_multi_queue
&& *nr_events
< min
;
2466 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2467 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2471 * Move completed and retryable entries to our local lists.
2472 * If we find a request that requires polling, break out
2473 * and complete those lists first, if we have entries there.
2475 if (READ_ONCE(req
->iopoll_completed
)) {
2476 list_move_tail(&req
->inflight_entry
, &done
);
2479 if (!list_empty(&done
))
2482 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2483 if (unlikely(ret
< 0))
2488 /* iopoll may have completed current req */
2489 if (READ_ONCE(req
->iopoll_completed
))
2490 list_move_tail(&req
->inflight_entry
, &done
);
2493 if (!list_empty(&done
))
2494 io_iopoll_complete(ctx
, nr_events
, &done
);
2500 * We can't just wait for polled events to come to us, we have to actively
2501 * find and complete them.
2503 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2505 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2508 mutex_lock(&ctx
->uring_lock
);
2509 while (!list_empty(&ctx
->iopoll_list
)) {
2510 unsigned int nr_events
= 0;
2512 io_do_iopoll(ctx
, &nr_events
, 0);
2514 /* let it sleep and repeat later if can't complete a request */
2518 * Ensure we allow local-to-the-cpu processing to take place,
2519 * in this case we need to ensure that we reap all events.
2520 * Also let task_work, etc. to progress by releasing the mutex
2522 if (need_resched()) {
2523 mutex_unlock(&ctx
->uring_lock
);
2525 mutex_lock(&ctx
->uring_lock
);
2528 mutex_unlock(&ctx
->uring_lock
);
2531 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2533 unsigned int nr_events
= 0;
2537 * We disallow the app entering submit/complete with polling, but we
2538 * still need to lock the ring to prevent racing with polled issue
2539 * that got punted to a workqueue.
2541 mutex_lock(&ctx
->uring_lock
);
2543 * Don't enter poll loop if we already have events pending.
2544 * If we do, we can potentially be spinning for commands that
2545 * already triggered a CQE (eg in error).
2547 if (test_bit(0, &ctx
->check_cq_overflow
))
2548 __io_cqring_overflow_flush(ctx
, false);
2549 if (io_cqring_events(ctx
))
2553 * If a submit got punted to a workqueue, we can have the
2554 * application entering polling for a command before it gets
2555 * issued. That app will hold the uring_lock for the duration
2556 * of the poll right here, so we need to take a breather every
2557 * now and then to ensure that the issue has a chance to add
2558 * the poll to the issued list. Otherwise we can spin here
2559 * forever, while the workqueue is stuck trying to acquire the
2562 if (list_empty(&ctx
->iopoll_list
)) {
2563 u32 tail
= ctx
->cached_cq_tail
;
2565 mutex_unlock(&ctx
->uring_lock
);
2567 mutex_lock(&ctx
->uring_lock
);
2569 /* some requests don't go through iopoll_list */
2570 if (tail
!= ctx
->cached_cq_tail
||
2571 list_empty(&ctx
->iopoll_list
))
2574 ret
= io_do_iopoll(ctx
, &nr_events
, min
);
2575 } while (!ret
&& nr_events
< min
&& !need_resched());
2577 mutex_unlock(&ctx
->uring_lock
);
2581 static void kiocb_end_write(struct io_kiocb
*req
)
2584 * Tell lockdep we inherited freeze protection from submission
2587 if (req
->flags
& REQ_F_ISREG
) {
2588 struct super_block
*sb
= file_inode(req
->file
)->i_sb
;
2590 __sb_writers_acquired(sb
, SB_FREEZE_WRITE
);
2596 static bool io_resubmit_prep(struct io_kiocb
*req
)
2598 struct io_async_rw
*rw
= req
->async_data
;
2601 return !io_req_prep_async(req
);
2602 iov_iter_restore(&rw
->iter
, &rw
->iter_state
);
2606 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2608 umode_t mode
= file_inode(req
->file
)->i_mode
;
2609 struct io_ring_ctx
*ctx
= req
->ctx
;
2611 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2613 if ((req
->flags
& REQ_F_NOWAIT
) || (io_wq_current_is_worker() &&
2614 !(ctx
->flags
& IORING_SETUP_IOPOLL
)))
2617 * If ref is dying, we might be running poll reap from the exit work.
2618 * Don't attempt to reissue from that path, just let it fail with
2621 if (percpu_ref_is_dying(&ctx
->refs
))
2624 * Play it safe and assume not safe to re-import and reissue if we're
2625 * not in the original thread group (or in task context).
2627 if (!same_thread_group(req
->task
, current
) || !in_task())
2632 static bool io_resubmit_prep(struct io_kiocb
*req
)
2636 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2642 static bool __io_complete_rw_common(struct io_kiocb
*req
, long res
)
2644 if (req
->rw
.kiocb
.ki_flags
& IOCB_WRITE
)
2645 kiocb_end_write(req
);
2646 if (res
!= req
->result
) {
2647 if ((res
== -EAGAIN
|| res
== -EOPNOTSUPP
) &&
2648 io_rw_should_reissue(req
)) {
2649 req
->flags
|= REQ_F_REISSUE
;
2658 static void io_req_task_complete(struct io_kiocb
*req
, bool *locked
)
2660 unsigned int cflags
= io_put_rw_kbuf(req
);
2661 long res
= req
->result
;
2664 struct io_ring_ctx
*ctx
= req
->ctx
;
2665 struct io_submit_state
*state
= &ctx
->submit_state
;
2667 io_req_complete_state(req
, res
, cflags
);
2668 state
->compl_reqs
[state
->compl_nr
++] = req
;
2669 if (state
->compl_nr
== ARRAY_SIZE(state
->compl_reqs
))
2670 io_submit_flush_completions(ctx
);
2672 io_req_complete_post(req
, res
, cflags
);
2676 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2677 unsigned int issue_flags
)
2679 if (__io_complete_rw_common(req
, res
))
2681 __io_req_complete(req
, issue_flags
, req
->result
, io_put_rw_kbuf(req
));
2684 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2686 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2688 if (__io_complete_rw_common(req
, res
))
2691 req
->io_task_work
.func
= io_req_task_complete
;
2692 io_req_task_work_add(req
);
2695 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2697 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2699 if (kiocb
->ki_flags
& IOCB_WRITE
)
2700 kiocb_end_write(req
);
2701 if (unlikely(res
!= req
->result
)) {
2702 if (res
== -EAGAIN
&& io_rw_should_reissue(req
)) {
2703 req
->flags
|= REQ_F_REISSUE
;
2708 WRITE_ONCE(req
->result
, res
);
2709 /* order with io_iopoll_complete() checking ->result */
2711 WRITE_ONCE(req
->iopoll_completed
, 1);
2715 * After the iocb has been issued, it's safe to be found on the poll list.
2716 * Adding the kiocb to the list AFTER submission ensures that we don't
2717 * find it from a io_do_iopoll() thread before the issuer is done
2718 * accessing the kiocb cookie.
2720 static void io_iopoll_req_issued(struct io_kiocb
*req
)
2722 struct io_ring_ctx
*ctx
= req
->ctx
;
2723 const bool in_async
= io_wq_current_is_worker();
2725 /* workqueue context doesn't hold uring_lock, grab it now */
2726 if (unlikely(in_async
))
2727 mutex_lock(&ctx
->uring_lock
);
2730 * Track whether we have multiple files in our lists. This will impact
2731 * how we do polling eventually, not spinning if we're on potentially
2732 * different devices.
2734 if (list_empty(&ctx
->iopoll_list
)) {
2735 ctx
->poll_multi_queue
= false;
2736 } else if (!ctx
->poll_multi_queue
) {
2737 struct io_kiocb
*list_req
;
2738 unsigned int queue_num0
, queue_num1
;
2740 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2743 if (list_req
->file
!= req
->file
) {
2744 ctx
->poll_multi_queue
= true;
2746 queue_num0
= blk_qc_t_to_queue_num(list_req
->rw
.kiocb
.ki_cookie
);
2747 queue_num1
= blk_qc_t_to_queue_num(req
->rw
.kiocb
.ki_cookie
);
2748 if (queue_num0
!= queue_num1
)
2749 ctx
->poll_multi_queue
= true;
2754 * For fast devices, IO may have already completed. If it has, add
2755 * it to the front so we find it first.
2757 if (READ_ONCE(req
->iopoll_completed
))
2758 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2760 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2762 if (unlikely(in_async
)) {
2764 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
2765 * in sq thread task context or in io worker task context. If
2766 * current task context is sq thread, we don't need to check
2767 * whether should wake up sq thread.
2769 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2770 wq_has_sleeper(&ctx
->sq_data
->wait
))
2771 wake_up(&ctx
->sq_data
->wait
);
2773 mutex_unlock(&ctx
->uring_lock
);
2777 static bool io_bdev_nowait(struct block_device
*bdev
)
2779 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2783 * If we tracked the file through the SCM inflight mechanism, we could support
2784 * any file. For now, just ensure that anything potentially problematic is done
2787 static bool __io_file_supports_nowait(struct file
*file
, int rw
)
2789 umode_t mode
= file_inode(file
)->i_mode
;
2791 if (S_ISBLK(mode
)) {
2792 if (IS_ENABLED(CONFIG_BLOCK
) &&
2793 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2799 if (S_ISREG(mode
)) {
2800 if (IS_ENABLED(CONFIG_BLOCK
) &&
2801 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2802 file
->f_op
!= &io_uring_fops
)
2807 /* any ->read/write should understand O_NONBLOCK */
2808 if (file
->f_flags
& O_NONBLOCK
)
2811 if (!(file
->f_mode
& FMODE_NOWAIT
))
2815 return file
->f_op
->read_iter
!= NULL
;
2817 return file
->f_op
->write_iter
!= NULL
;
2820 static bool io_file_supports_nowait(struct io_kiocb
*req
, int rw
)
2822 if (rw
== READ
&& (req
->flags
& REQ_F_NOWAIT_READ
))
2824 else if (rw
== WRITE
&& (req
->flags
& REQ_F_NOWAIT_WRITE
))
2827 return __io_file_supports_nowait(req
->file
, rw
);
2830 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2833 struct io_ring_ctx
*ctx
= req
->ctx
;
2834 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2835 struct file
*file
= req
->file
;
2839 if (!io_req_ffs_set(req
) && S_ISREG(file_inode(file
)->i_mode
))
2840 req
->flags
|= REQ_F_ISREG
;
2842 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2843 if (kiocb
->ki_pos
== -1 && !(file
->f_mode
& FMODE_STREAM
)) {
2844 req
->flags
|= REQ_F_CUR_POS
;
2845 kiocb
->ki_pos
= file
->f_pos
;
2847 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2848 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2849 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2854 * If the file is marked O_NONBLOCK, still allow retry for it if it
2855 * supports async. Otherwise it's impossible to use O_NONBLOCK files
2856 * reliably. If not, or it IOCB_NOWAIT is set, don't retry.
2858 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) ||
2859 ((file
->f_flags
& O_NONBLOCK
) && !io_file_supports_nowait(req
, rw
)))
2860 req
->flags
|= REQ_F_NOWAIT
;
2862 ioprio
= READ_ONCE(sqe
->ioprio
);
2864 ret
= ioprio_check_cap(ioprio
);
2868 kiocb
->ki_ioprio
= ioprio
;
2870 kiocb
->ki_ioprio
= get_current_ioprio();
2872 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2873 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2874 !kiocb
->ki_filp
->f_op
->iopoll
)
2877 kiocb
->ki_flags
|= IOCB_HIPRI
| IOCB_ALLOC_CACHE
;
2878 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2879 req
->iopoll_completed
= 0;
2881 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2883 kiocb
->ki_complete
= io_complete_rw
;
2886 if (req
->opcode
== IORING_OP_READ_FIXED
||
2887 req
->opcode
== IORING_OP_WRITE_FIXED
) {
2889 io_req_set_rsrc_node(req
);
2892 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2893 req
->rw
.len
= READ_ONCE(sqe
->len
);
2894 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2898 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2904 case -ERESTARTNOINTR
:
2905 case -ERESTARTNOHAND
:
2906 case -ERESTART_RESTARTBLOCK
:
2908 * We can't just restart the syscall, since previously
2909 * submitted sqes may already be in progress. Just fail this
2915 kiocb
->ki_complete(kiocb
, ret
, 0);
2919 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2920 unsigned int issue_flags
)
2922 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2923 struct io_async_rw
*io
= req
->async_data
;
2925 /* add previously done IO, if any */
2926 if (io
&& io
->bytes_done
> 0) {
2928 ret
= io
->bytes_done
;
2930 ret
+= io
->bytes_done
;
2933 if (req
->flags
& REQ_F_CUR_POS
)
2934 req
->file
->f_pos
= kiocb
->ki_pos
;
2935 if (ret
>= 0 && (kiocb
->ki_complete
== io_complete_rw
))
2936 __io_complete_rw(req
, ret
, 0, issue_flags
);
2938 io_rw_done(kiocb
, ret
);
2940 if (req
->flags
& REQ_F_REISSUE
) {
2941 req
->flags
&= ~REQ_F_REISSUE
;
2942 if (io_resubmit_prep(req
)) {
2943 io_req_task_queue_reissue(req
);
2945 unsigned int cflags
= io_put_rw_kbuf(req
);
2946 struct io_ring_ctx
*ctx
= req
->ctx
;
2949 if (!(issue_flags
& IO_URING_F_NONBLOCK
)) {
2950 mutex_lock(&ctx
->uring_lock
);
2951 __io_req_complete(req
, issue_flags
, ret
, cflags
);
2952 mutex_unlock(&ctx
->uring_lock
);
2954 __io_req_complete(req
, issue_flags
, ret
, cflags
);
2960 static int __io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
,
2961 struct io_mapped_ubuf
*imu
)
2963 size_t len
= req
->rw
.len
;
2964 u64 buf_end
, buf_addr
= req
->rw
.addr
;
2967 if (unlikely(check_add_overflow(buf_addr
, (u64
)len
, &buf_end
)))
2969 /* not inside the mapped region */
2970 if (unlikely(buf_addr
< imu
->ubuf
|| buf_end
> imu
->ubuf_end
))
2974 * May not be a start of buffer, set size appropriately
2975 * and advance us to the beginning.
2977 offset
= buf_addr
- imu
->ubuf
;
2978 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2982 * Don't use iov_iter_advance() here, as it's really slow for
2983 * using the latter parts of a big fixed buffer - it iterates
2984 * over each segment manually. We can cheat a bit here, because
2987 * 1) it's a BVEC iter, we set it up
2988 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2989 * first and last bvec
2991 * So just find our index, and adjust the iterator afterwards.
2992 * If the offset is within the first bvec (or the whole first
2993 * bvec, just use iov_iter_advance(). This makes it easier
2994 * since we can just skip the first segment, which may not
2995 * be PAGE_SIZE aligned.
2997 const struct bio_vec
*bvec
= imu
->bvec
;
2999 if (offset
<= bvec
->bv_len
) {
3000 iov_iter_advance(iter
, offset
);
3002 unsigned long seg_skip
;
3004 /* skip first vec */
3005 offset
-= bvec
->bv_len
;
3006 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
3008 iter
->bvec
= bvec
+ seg_skip
;
3009 iter
->nr_segs
-= seg_skip
;
3010 iter
->count
-= bvec
->bv_len
+ offset
;
3011 iter
->iov_offset
= offset
& ~PAGE_MASK
;
3018 static int io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
)
3020 struct io_ring_ctx
*ctx
= req
->ctx
;
3021 struct io_mapped_ubuf
*imu
= req
->imu
;
3022 u16 index
, buf_index
= req
->buf_index
;
3025 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
3027 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
3028 imu
= READ_ONCE(ctx
->user_bufs
[index
]);
3031 return __io_import_fixed(req
, rw
, iter
, imu
);
3034 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3037 mutex_unlock(&ctx
->uring_lock
);
3040 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3043 * "Normal" inline submissions always hold the uring_lock, since we
3044 * grab it from the system call. Same is true for the SQPOLL offload.
3045 * The only exception is when we've detached the request and issue it
3046 * from an async worker thread, grab the lock for that case.
3049 mutex_lock(&ctx
->uring_lock
);
3052 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
3053 int bgid
, struct io_buffer
*kbuf
,
3056 struct io_buffer
*head
;
3058 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
3061 io_ring_submit_lock(req
->ctx
, needs_lock
);
3063 lockdep_assert_held(&req
->ctx
->uring_lock
);
3065 head
= xa_load(&req
->ctx
->io_buffers
, bgid
);
3067 if (!list_empty(&head
->list
)) {
3068 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
3070 list_del(&kbuf
->list
);
3073 xa_erase(&req
->ctx
->io_buffers
, bgid
);
3075 if (*len
> kbuf
->len
)
3078 kbuf
= ERR_PTR(-ENOBUFS
);
3081 io_ring_submit_unlock(req
->ctx
, needs_lock
);
3086 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
3089 struct io_buffer
*kbuf
;
3092 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3093 bgid
= req
->buf_index
;
3094 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
3097 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
3098 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3099 return u64_to_user_ptr(kbuf
->addr
);
3102 #ifdef CONFIG_COMPAT
3103 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
3106 struct compat_iovec __user
*uiov
;
3107 compat_ssize_t clen
;
3111 uiov
= u64_to_user_ptr(req
->rw
.addr
);
3112 if (!access_ok(uiov
, sizeof(*uiov
)))
3114 if (__get_user(clen
, &uiov
->iov_len
))
3120 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3122 return PTR_ERR(buf
);
3123 iov
[0].iov_base
= buf
;
3124 iov
[0].iov_len
= (compat_size_t
) len
;
3129 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3132 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
3136 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3139 len
= iov
[0].iov_len
;
3142 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3144 return PTR_ERR(buf
);
3145 iov
[0].iov_base
= buf
;
3146 iov
[0].iov_len
= len
;
3150 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3153 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3154 struct io_buffer
*kbuf
;
3156 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3157 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3158 iov
[0].iov_len
= kbuf
->len
;
3161 if (req
->rw
.len
!= 1)
3164 #ifdef CONFIG_COMPAT
3165 if (req
->ctx
->compat
)
3166 return io_compat_import(req
, iov
, needs_lock
);
3169 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3172 static int io_import_iovec(int rw
, struct io_kiocb
*req
, struct iovec
**iovec
,
3173 struct iov_iter
*iter
, bool needs_lock
)
3175 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3176 size_t sqe_len
= req
->rw
.len
;
3177 u8 opcode
= req
->opcode
;
3180 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3182 return io_import_fixed(req
, rw
, iter
);
3185 /* buffer index only valid with fixed read/write, or buffer select */
3186 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3189 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3190 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3191 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3193 return PTR_ERR(buf
);
3194 req
->rw
.len
= sqe_len
;
3197 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3202 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3203 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3205 iov_iter_init(iter
, rw
, *iovec
, 1, (*iovec
)->iov_len
);
3210 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3214 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3216 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3220 * For files that don't have ->read_iter() and ->write_iter(), handle them
3221 * by looping over ->read() or ->write() manually.
3223 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3225 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3226 struct file
*file
= req
->file
;
3230 * Don't support polled IO through this interface, and we can't
3231 * support non-blocking either. For the latter, this just causes
3232 * the kiocb to be handled from an async context.
3234 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3236 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3239 while (iov_iter_count(iter
)) {
3243 if (!iov_iter_is_bvec(iter
)) {
3244 iovec
= iov_iter_iovec(iter
);
3246 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3247 iovec
.iov_len
= req
->rw
.len
;
3251 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3252 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3254 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3255 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3263 if (!iov_iter_is_bvec(iter
)) {
3264 iov_iter_advance(iter
, nr
);
3270 if (nr
!= iovec
.iov_len
)
3277 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3278 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3280 struct io_async_rw
*rw
= req
->async_data
;
3282 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3283 rw
->free_iovec
= iovec
;
3285 /* can only be fixed buffers, no need to do anything */
3286 if (iov_iter_is_bvec(iter
))
3289 unsigned iov_off
= 0;
3291 rw
->iter
.iov
= rw
->fast_iov
;
3292 if (iter
->iov
!= fast_iov
) {
3293 iov_off
= iter
->iov
- fast_iov
;
3294 rw
->iter
.iov
+= iov_off
;
3296 if (rw
->fast_iov
!= fast_iov
)
3297 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3298 sizeof(struct iovec
) * iter
->nr_segs
);
3300 req
->flags
|= REQ_F_NEED_CLEANUP
;
3304 static inline int io_alloc_async_data(struct io_kiocb
*req
)
3306 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3307 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3308 return req
->async_data
== NULL
;
3311 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3312 const struct iovec
*fast_iov
,
3313 struct iov_iter
*iter
, bool force
)
3315 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_setup
)
3317 if (!req
->async_data
) {
3318 struct io_async_rw
*iorw
;
3320 if (io_alloc_async_data(req
)) {
3325 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3326 iorw
= req
->async_data
;
3327 /* we've copied and mapped the iter, ensure state is saved */
3328 iov_iter_save_state(&iorw
->iter
, &iorw
->iter_state
);
3333 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3335 struct io_async_rw
*iorw
= req
->async_data
;
3336 struct iovec
*iov
= iorw
->fast_iov
;
3339 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3340 if (unlikely(ret
< 0))
3343 iorw
->bytes_done
= 0;
3344 iorw
->free_iovec
= iov
;
3346 req
->flags
|= REQ_F_NEED_CLEANUP
;
3347 iov_iter_save_state(&iorw
->iter
, &iorw
->iter_state
);
3351 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3353 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3355 return io_prep_rw(req
, sqe
, READ
);
3359 * This is our waitqueue callback handler, registered through lock_page_async()
3360 * when we initially tried to do the IO with the iocb armed our waitqueue.
3361 * This gets called when the page is unlocked, and we generally expect that to
3362 * happen when the page IO is completed and the page is now uptodate. This will
3363 * queue a task_work based retry of the operation, attempting to copy the data
3364 * again. If the latter fails because the page was NOT uptodate, then we will
3365 * do a thread based blocking retry of the operation. That's the unexpected
3368 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3369 int sync
, void *arg
)
3371 struct wait_page_queue
*wpq
;
3372 struct io_kiocb
*req
= wait
->private;
3373 struct wait_page_key
*key
= arg
;
3375 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3377 if (!wake_page_match(wpq
, key
))
3380 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3381 list_del_init(&wait
->entry
);
3382 io_req_task_queue(req
);
3387 * This controls whether a given IO request should be armed for async page
3388 * based retry. If we return false here, the request is handed to the async
3389 * worker threads for retry. If we're doing buffered reads on a regular file,
3390 * we prepare a private wait_page_queue entry and retry the operation. This
3391 * will either succeed because the page is now uptodate and unlocked, or it
3392 * will register a callback when the page is unlocked at IO completion. Through
3393 * that callback, io_uring uses task_work to setup a retry of the operation.
3394 * That retry will attempt the buffered read again. The retry will generally
3395 * succeed, or in rare cases where it fails, we then fall back to using the
3396 * async worker threads for a blocking retry.
3398 static bool io_rw_should_retry(struct io_kiocb
*req
)
3400 struct io_async_rw
*rw
= req
->async_data
;
3401 struct wait_page_queue
*wait
= &rw
->wpq
;
3402 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3404 /* never retry for NOWAIT, we just complete with -EAGAIN */
3405 if (req
->flags
& REQ_F_NOWAIT
)
3408 /* Only for buffered IO */
3409 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3413 * just use poll if we can, and don't attempt if the fs doesn't
3414 * support callback based unlocks
3416 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3419 wait
->wait
.func
= io_async_buf_func
;
3420 wait
->wait
.private = req
;
3421 wait
->wait
.flags
= 0;
3422 INIT_LIST_HEAD(&wait
->wait
.entry
);
3423 kiocb
->ki_flags
|= IOCB_WAITQ
;
3424 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3425 kiocb
->ki_waitq
= wait
;
3429 static inline int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3431 if (req
->file
->f_op
->read_iter
)
3432 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3433 else if (req
->file
->f_op
->read
)
3434 return loop_rw_iter(READ
, req
, iter
);
3439 static bool need_read_all(struct io_kiocb
*req
)
3441 return req
->flags
& REQ_F_ISREG
||
3442 S_ISBLK(file_inode(req
->file
)->i_mode
);
3445 static int io_read(struct io_kiocb
*req
, unsigned int issue_flags
)
3447 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3448 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3449 struct iov_iter __iter
, *iter
= &__iter
;
3450 struct io_async_rw
*rw
= req
->async_data
;
3451 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3452 struct iov_iter_state __state
, *state
;
3457 state
= &rw
->iter_state
;
3459 * We come here from an earlier attempt, restore our state to
3460 * match in case it doesn't. It's cheap enough that we don't
3461 * need to make this conditional.
3463 iov_iter_restore(iter
, state
);
3466 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3470 iov_iter_save_state(iter
, state
);
3472 req
->result
= iov_iter_count(iter
);
3474 /* Ensure we clear previously set non-block flag */
3475 if (!force_nonblock
)
3476 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3478 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3480 /* If the file doesn't support async, just async punt */
3481 if (force_nonblock
&& !io_file_supports_nowait(req
, READ
)) {
3482 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3483 return ret
?: -EAGAIN
;
3486 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), req
->result
);
3487 if (unlikely(ret
)) {
3492 ret
= io_iter_do_read(req
, iter
);
3494 if (ret
== -EAGAIN
|| (req
->flags
& REQ_F_REISSUE
)) {
3495 req
->flags
&= ~REQ_F_REISSUE
;
3496 /* IOPOLL retry should happen for io-wq threads */
3497 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3499 /* no retry on NONBLOCK nor RWF_NOWAIT */
3500 if (req
->flags
& REQ_F_NOWAIT
)
3503 } else if (ret
== -EIOCBQUEUED
) {
3505 } else if (ret
<= 0 || ret
== req
->result
|| !force_nonblock
||
3506 (req
->flags
& REQ_F_NOWAIT
) || !need_read_all(req
)) {
3507 /* read all, failed, already did sync or don't want to retry */
3512 * Don't depend on the iter state matching what was consumed, or being
3513 * untouched in case of error. Restore it and we'll advance it
3514 * manually if we need to.
3516 iov_iter_restore(iter
, state
);
3518 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3523 rw
= req
->async_data
;
3525 * Now use our persistent iterator and state, if we aren't already.
3526 * We've restored and mapped the iter to match.
3528 if (iter
!= &rw
->iter
) {
3530 state
= &rw
->iter_state
;
3535 * We end up here because of a partial read, either from
3536 * above or inside this loop. Advance the iter by the bytes
3537 * that were consumed.
3539 iov_iter_advance(iter
, ret
);
3540 if (!iov_iter_count(iter
))
3542 rw
->bytes_done
+= ret
;
3543 iov_iter_save_state(iter
, state
);
3545 /* if we can retry, do so with the callbacks armed */
3546 if (!io_rw_should_retry(req
)) {
3547 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3552 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3553 * we get -EIOCBQUEUED, then we'll get a notification when the
3554 * desired page gets unlocked. We can also get a partial read
3555 * here, and if we do, then just retry at the new offset.
3557 ret
= io_iter_do_read(req
, iter
);
3558 if (ret
== -EIOCBQUEUED
)
3560 /* we got some bytes, but not all. retry. */
3561 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3562 iov_iter_restore(iter
, state
);
3565 kiocb_done(kiocb
, ret
, issue_flags
);
3567 /* it's faster to check here then delegate to kfree */
3573 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3575 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3577 return io_prep_rw(req
, sqe
, WRITE
);
3580 static int io_write(struct io_kiocb
*req
, unsigned int issue_flags
)
3582 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3583 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3584 struct iov_iter __iter
, *iter
= &__iter
;
3585 struct io_async_rw
*rw
= req
->async_data
;
3586 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3587 struct iov_iter_state __state
, *state
;
3592 state
= &rw
->iter_state
;
3593 iov_iter_restore(iter
, state
);
3596 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3600 iov_iter_save_state(iter
, state
);
3602 req
->result
= iov_iter_count(iter
);
3604 /* Ensure we clear previously set non-block flag */
3605 if (!force_nonblock
)
3606 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3608 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3610 /* If the file doesn't support async, just async punt */
3611 if (force_nonblock
&& !io_file_supports_nowait(req
, WRITE
))
3614 /* file path doesn't support NOWAIT for non-direct_IO */
3615 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3616 (req
->flags
& REQ_F_ISREG
))
3619 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), req
->result
);
3624 * Open-code file_start_write here to grab freeze protection,
3625 * which will be released by another thread in
3626 * io_complete_rw(). Fool lockdep by telling it the lock got
3627 * released so that it doesn't complain about the held lock when
3628 * we return to userspace.
3630 if (req
->flags
& REQ_F_ISREG
) {
3631 sb_start_write(file_inode(req
->file
)->i_sb
);
3632 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3635 kiocb
->ki_flags
|= IOCB_WRITE
;
3637 if (req
->file
->f_op
->write_iter
)
3638 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3639 else if (req
->file
->f_op
->write
)
3640 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3644 if (req
->flags
& REQ_F_REISSUE
) {
3645 req
->flags
&= ~REQ_F_REISSUE
;
3650 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3651 * retry them without IOCB_NOWAIT.
3653 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3655 /* no retry on NONBLOCK nor RWF_NOWAIT */
3656 if (ret2
== -EAGAIN
&& (req
->flags
& REQ_F_NOWAIT
))
3658 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3659 /* IOPOLL retry should happen for io-wq threads */
3660 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3663 kiocb_done(kiocb
, ret2
, issue_flags
);
3666 iov_iter_restore(iter
, state
);
3667 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3668 return ret
?: -EAGAIN
;
3671 /* it's reportedly faster than delegating the null check to kfree() */
3677 static int io_renameat_prep(struct io_kiocb
*req
,
3678 const struct io_uring_sqe
*sqe
)
3680 struct io_rename
*ren
= &req
->rename
;
3681 const char __user
*oldf
, *newf
;
3683 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3685 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
3687 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3690 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3691 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3692 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3693 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3694 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3696 ren
->oldpath
= getname(oldf
);
3697 if (IS_ERR(ren
->oldpath
))
3698 return PTR_ERR(ren
->oldpath
);
3700 ren
->newpath
= getname(newf
);
3701 if (IS_ERR(ren
->newpath
)) {
3702 putname(ren
->oldpath
);
3703 return PTR_ERR(ren
->newpath
);
3706 req
->flags
|= REQ_F_NEED_CLEANUP
;
3710 static int io_renameat(struct io_kiocb
*req
, unsigned int issue_flags
)
3712 struct io_rename
*ren
= &req
->rename
;
3715 if (issue_flags
& IO_URING_F_NONBLOCK
)
3718 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3719 ren
->newpath
, ren
->flags
);
3721 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3724 io_req_complete(req
, ret
);
3728 static int io_unlinkat_prep(struct io_kiocb
*req
,
3729 const struct io_uring_sqe
*sqe
)
3731 struct io_unlink
*un
= &req
->unlink
;
3732 const char __user
*fname
;
3734 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3736 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
3739 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3742 un
->dfd
= READ_ONCE(sqe
->fd
);
3744 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3745 if (un
->flags
& ~AT_REMOVEDIR
)
3748 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3749 un
->filename
= getname(fname
);
3750 if (IS_ERR(un
->filename
))
3751 return PTR_ERR(un
->filename
);
3753 req
->flags
|= REQ_F_NEED_CLEANUP
;
3757 static int io_unlinkat(struct io_kiocb
*req
, unsigned int issue_flags
)
3759 struct io_unlink
*un
= &req
->unlink
;
3762 if (issue_flags
& IO_URING_F_NONBLOCK
)
3765 if (un
->flags
& AT_REMOVEDIR
)
3766 ret
= do_rmdir(un
->dfd
, un
->filename
);
3768 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3770 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3773 io_req_complete(req
, ret
);
3777 static int io_mkdirat_prep(struct io_kiocb
*req
,
3778 const struct io_uring_sqe
*sqe
)
3780 struct io_mkdir
*mkd
= &req
->mkdir
;
3781 const char __user
*fname
;
3783 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3785 if (sqe
->ioprio
|| sqe
->off
|| sqe
->rw_flags
|| sqe
->buf_index
||
3788 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3791 mkd
->dfd
= READ_ONCE(sqe
->fd
);
3792 mkd
->mode
= READ_ONCE(sqe
->len
);
3794 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3795 mkd
->filename
= getname(fname
);
3796 if (IS_ERR(mkd
->filename
))
3797 return PTR_ERR(mkd
->filename
);
3799 req
->flags
|= REQ_F_NEED_CLEANUP
;
3803 static int io_mkdirat(struct io_kiocb
*req
, int issue_flags
)
3805 struct io_mkdir
*mkd
= &req
->mkdir
;
3808 if (issue_flags
& IO_URING_F_NONBLOCK
)
3811 ret
= do_mkdirat(mkd
->dfd
, mkd
->filename
, mkd
->mode
);
3813 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3816 io_req_complete(req
, ret
);
3820 static int io_symlinkat_prep(struct io_kiocb
*req
,
3821 const struct io_uring_sqe
*sqe
)
3823 struct io_symlink
*sl
= &req
->symlink
;
3824 const char __user
*oldpath
, *newpath
;
3826 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3828 if (sqe
->ioprio
|| sqe
->len
|| sqe
->rw_flags
|| sqe
->buf_index
||
3831 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3834 sl
->new_dfd
= READ_ONCE(sqe
->fd
);
3835 oldpath
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3836 newpath
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3838 sl
->oldpath
= getname(oldpath
);
3839 if (IS_ERR(sl
->oldpath
))
3840 return PTR_ERR(sl
->oldpath
);
3842 sl
->newpath
= getname(newpath
);
3843 if (IS_ERR(sl
->newpath
)) {
3844 putname(sl
->oldpath
);
3845 return PTR_ERR(sl
->newpath
);
3848 req
->flags
|= REQ_F_NEED_CLEANUP
;
3852 static int io_symlinkat(struct io_kiocb
*req
, int issue_flags
)
3854 struct io_symlink
*sl
= &req
->symlink
;
3857 if (issue_flags
& IO_URING_F_NONBLOCK
)
3860 ret
= do_symlinkat(sl
->oldpath
, sl
->new_dfd
, sl
->newpath
);
3862 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3865 io_req_complete(req
, ret
);
3869 static int io_linkat_prep(struct io_kiocb
*req
,
3870 const struct io_uring_sqe
*sqe
)
3872 struct io_hardlink
*lnk
= &req
->hardlink
;
3873 const char __user
*oldf
, *newf
;
3875 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3877 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
3879 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3882 lnk
->old_dfd
= READ_ONCE(sqe
->fd
);
3883 lnk
->new_dfd
= READ_ONCE(sqe
->len
);
3884 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3885 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3886 lnk
->flags
= READ_ONCE(sqe
->hardlink_flags
);
3888 lnk
->oldpath
= getname(oldf
);
3889 if (IS_ERR(lnk
->oldpath
))
3890 return PTR_ERR(lnk
->oldpath
);
3892 lnk
->newpath
= getname(newf
);
3893 if (IS_ERR(lnk
->newpath
)) {
3894 putname(lnk
->oldpath
);
3895 return PTR_ERR(lnk
->newpath
);
3898 req
->flags
|= REQ_F_NEED_CLEANUP
;
3902 static int io_linkat(struct io_kiocb
*req
, int issue_flags
)
3904 struct io_hardlink
*lnk
= &req
->hardlink
;
3907 if (issue_flags
& IO_URING_F_NONBLOCK
)
3910 ret
= do_linkat(lnk
->old_dfd
, lnk
->oldpath
, lnk
->new_dfd
,
3911 lnk
->newpath
, lnk
->flags
);
3913 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3916 io_req_complete(req
, ret
);
3920 static int io_shutdown_prep(struct io_kiocb
*req
,
3921 const struct io_uring_sqe
*sqe
)
3923 #if defined(CONFIG_NET)
3924 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3926 if (unlikely(sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3927 sqe
->buf_index
|| sqe
->splice_fd_in
))
3930 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3937 static int io_shutdown(struct io_kiocb
*req
, unsigned int issue_flags
)
3939 #if defined(CONFIG_NET)
3940 struct socket
*sock
;
3943 if (issue_flags
& IO_URING_F_NONBLOCK
)
3946 sock
= sock_from_file(req
->file
);
3947 if (unlikely(!sock
))
3950 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3953 io_req_complete(req
, ret
);
3960 static int __io_splice_prep(struct io_kiocb
*req
,
3961 const struct io_uring_sqe
*sqe
)
3963 struct io_splice
*sp
= &req
->splice
;
3964 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3966 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3970 sp
->len
= READ_ONCE(sqe
->len
);
3971 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3973 if (unlikely(sp
->flags
& ~valid_flags
))
3976 sp
->file_in
= io_file_get(req
->ctx
, req
, READ_ONCE(sqe
->splice_fd_in
),
3977 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3980 req
->flags
|= REQ_F_NEED_CLEANUP
;
3984 static int io_tee_prep(struct io_kiocb
*req
,
3985 const struct io_uring_sqe
*sqe
)
3987 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3989 return __io_splice_prep(req
, sqe
);
3992 static int io_tee(struct io_kiocb
*req
, unsigned int issue_flags
)
3994 struct io_splice
*sp
= &req
->splice
;
3995 struct file
*in
= sp
->file_in
;
3996 struct file
*out
= sp
->file_out
;
3997 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
4000 if (issue_flags
& IO_URING_F_NONBLOCK
)
4003 ret
= do_tee(in
, out
, sp
->len
, flags
);
4005 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
4007 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4011 io_req_complete(req
, ret
);
4015 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4017 struct io_splice
*sp
= &req
->splice
;
4019 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
4020 sp
->off_out
= READ_ONCE(sqe
->off
);
4021 return __io_splice_prep(req
, sqe
);
4024 static int io_splice(struct io_kiocb
*req
, unsigned int issue_flags
)
4026 struct io_splice
*sp
= &req
->splice
;
4027 struct file
*in
= sp
->file_in
;
4028 struct file
*out
= sp
->file_out
;
4029 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
4030 loff_t
*poff_in
, *poff_out
;
4033 if (issue_flags
& IO_URING_F_NONBLOCK
)
4036 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
4037 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
4040 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
4042 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
4044 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4048 io_req_complete(req
, ret
);
4053 * IORING_OP_NOP just posts a completion event, nothing else.
4055 static int io_nop(struct io_kiocb
*req
, unsigned int issue_flags
)
4057 struct io_ring_ctx
*ctx
= req
->ctx
;
4059 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4062 __io_req_complete(req
, issue_flags
, 0, 0);
4066 static int io_fsync_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4068 struct io_ring_ctx
*ctx
= req
->ctx
;
4073 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4075 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
||
4079 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
4080 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
4083 req
->sync
.off
= READ_ONCE(sqe
->off
);
4084 req
->sync
.len
= READ_ONCE(sqe
->len
);
4088 static int io_fsync(struct io_kiocb
*req
, unsigned int issue_flags
)
4090 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
4093 /* fsync always requires a blocking context */
4094 if (issue_flags
& IO_URING_F_NONBLOCK
)
4097 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
4098 end
> 0 ? end
: LLONG_MAX
,
4099 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
4102 io_req_complete(req
, ret
);
4106 static int io_fallocate_prep(struct io_kiocb
*req
,
4107 const struct io_uring_sqe
*sqe
)
4109 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
||
4112 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4115 req
->sync
.off
= READ_ONCE(sqe
->off
);
4116 req
->sync
.len
= READ_ONCE(sqe
->addr
);
4117 req
->sync
.mode
= READ_ONCE(sqe
->len
);
4121 static int io_fallocate(struct io_kiocb
*req
, unsigned int issue_flags
)
4125 /* fallocate always requiring blocking context */
4126 if (issue_flags
& IO_URING_F_NONBLOCK
)
4128 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
4132 io_req_complete(req
, ret
);
4136 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4138 const char __user
*fname
;
4141 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4143 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
4145 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
4148 /* open.how should be already initialised */
4149 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
4150 req
->open
.how
.flags
|= O_LARGEFILE
;
4152 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
4153 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4154 req
->open
.filename
= getname(fname
);
4155 if (IS_ERR(req
->open
.filename
)) {
4156 ret
= PTR_ERR(req
->open
.filename
);
4157 req
->open
.filename
= NULL
;
4161 req
->open
.file_slot
= READ_ONCE(sqe
->file_index
);
4162 if (req
->open
.file_slot
&& (req
->open
.how
.flags
& O_CLOEXEC
))
4165 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
4166 req
->flags
|= REQ_F_NEED_CLEANUP
;
4170 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4172 u64 mode
= READ_ONCE(sqe
->len
);
4173 u64 flags
= READ_ONCE(sqe
->open_flags
);
4175 req
->open
.how
= build_open_how(flags
, mode
);
4176 return __io_openat_prep(req
, sqe
);
4179 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4181 struct open_how __user
*how
;
4185 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4186 len
= READ_ONCE(sqe
->len
);
4187 if (len
< OPEN_HOW_SIZE_VER0
)
4190 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
4195 return __io_openat_prep(req
, sqe
);
4198 static int io_openat2(struct io_kiocb
*req
, unsigned int issue_flags
)
4200 struct open_flags op
;
4202 bool resolve_nonblock
, nonblock_set
;
4203 bool fixed
= !!req
->open
.file_slot
;
4206 ret
= build_open_flags(&req
->open
.how
, &op
);
4209 nonblock_set
= op
.open_flag
& O_NONBLOCK
;
4210 resolve_nonblock
= req
->open
.how
.resolve
& RESOLVE_CACHED
;
4211 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4213 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
4214 * it'll always -EAGAIN
4216 if (req
->open
.how
.flags
& (O_TRUNC
| O_CREAT
| O_TMPFILE
))
4218 op
.lookup_flags
|= LOOKUP_CACHED
;
4219 op
.open_flag
|= O_NONBLOCK
;
4223 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
4228 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
4231 * We could hang on to this 'fd' on retrying, but seems like
4232 * marginal gain for something that is now known to be a slower
4233 * path. So just put it, and we'll get a new one when we retry.
4238 ret
= PTR_ERR(file
);
4239 /* only retry if RESOLVE_CACHED wasn't already set by application */
4240 if (ret
== -EAGAIN
&&
4241 (!resolve_nonblock
&& (issue_flags
& IO_URING_F_NONBLOCK
)))
4246 if ((issue_flags
& IO_URING_F_NONBLOCK
) && !nonblock_set
)
4247 file
->f_flags
&= ~O_NONBLOCK
;
4248 fsnotify_open(file
);
4251 fd_install(ret
, file
);
4253 ret
= io_install_fixed_file(req
, file
, issue_flags
,
4254 req
->open
.file_slot
- 1);
4256 putname(req
->open
.filename
);
4257 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4260 __io_req_complete(req
, issue_flags
, ret
, 0);
4264 static int io_openat(struct io_kiocb
*req
, unsigned int issue_flags
)
4266 return io_openat2(req
, issue_flags
);
4269 static int io_remove_buffers_prep(struct io_kiocb
*req
,
4270 const struct io_uring_sqe
*sqe
)
4272 struct io_provide_buf
*p
= &req
->pbuf
;
4275 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
||
4279 tmp
= READ_ONCE(sqe
->fd
);
4280 if (!tmp
|| tmp
> USHRT_MAX
)
4283 memset(p
, 0, sizeof(*p
));
4285 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4289 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
4290 int bgid
, unsigned nbufs
)
4294 /* shouldn't happen */
4298 /* the head kbuf is the list itself */
4299 while (!list_empty(&buf
->list
)) {
4300 struct io_buffer
*nxt
;
4302 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
4303 list_del(&nxt
->list
);
4310 xa_erase(&ctx
->io_buffers
, bgid
);
4315 static int io_remove_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
4317 struct io_provide_buf
*p
= &req
->pbuf
;
4318 struct io_ring_ctx
*ctx
= req
->ctx
;
4319 struct io_buffer
*head
;
4321 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4323 io_ring_submit_lock(ctx
, !force_nonblock
);
4325 lockdep_assert_held(&ctx
->uring_lock
);
4328 head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
4330 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
4334 /* complete before unlock, IOPOLL may need the lock */
4335 __io_req_complete(req
, issue_flags
, ret
, 0);
4336 io_ring_submit_unlock(ctx
, !force_nonblock
);
4340 static int io_provide_buffers_prep(struct io_kiocb
*req
,
4341 const struct io_uring_sqe
*sqe
)
4343 unsigned long size
, tmp_check
;
4344 struct io_provide_buf
*p
= &req
->pbuf
;
4347 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->splice_fd_in
)
4350 tmp
= READ_ONCE(sqe
->fd
);
4351 if (!tmp
|| tmp
> USHRT_MAX
)
4354 p
->addr
= READ_ONCE(sqe
->addr
);
4355 p
->len
= READ_ONCE(sqe
->len
);
4357 if (check_mul_overflow((unsigned long)p
->len
, (unsigned long)p
->nbufs
,
4360 if (check_add_overflow((unsigned long)p
->addr
, size
, &tmp_check
))
4363 size
= (unsigned long)p
->len
* p
->nbufs
;
4364 if (!access_ok(u64_to_user_ptr(p
->addr
), size
))
4367 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4368 tmp
= READ_ONCE(sqe
->off
);
4369 if (tmp
> USHRT_MAX
)
4375 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
4377 struct io_buffer
*buf
;
4378 u64 addr
= pbuf
->addr
;
4379 int i
, bid
= pbuf
->bid
;
4381 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
4382 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL_ACCOUNT
);
4387 buf
->len
= min_t(__u32
, pbuf
->len
, MAX_RW_COUNT
);
4392 INIT_LIST_HEAD(&buf
->list
);
4395 list_add_tail(&buf
->list
, &(*head
)->list
);
4399 return i
? i
: -ENOMEM
;
4402 static int io_provide_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
4404 struct io_provide_buf
*p
= &req
->pbuf
;
4405 struct io_ring_ctx
*ctx
= req
->ctx
;
4406 struct io_buffer
*head
, *list
;
4408 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4410 io_ring_submit_lock(ctx
, !force_nonblock
);
4412 lockdep_assert_held(&ctx
->uring_lock
);
4414 list
= head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
4416 ret
= io_add_buffers(p
, &head
);
4417 if (ret
>= 0 && !list
) {
4418 ret
= xa_insert(&ctx
->io_buffers
, p
->bgid
, head
, GFP_KERNEL
);
4420 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4424 /* complete before unlock, IOPOLL may need the lock */
4425 __io_req_complete(req
, issue_flags
, ret
, 0);
4426 io_ring_submit_unlock(ctx
, !force_nonblock
);
4430 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4431 const struct io_uring_sqe
*sqe
)
4433 #if defined(CONFIG_EPOLL)
4434 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
4436 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4439 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4440 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4441 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4443 if (ep_op_has_event(req
->epoll
.op
)) {
4444 struct epoll_event __user
*ev
;
4446 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4447 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4457 static int io_epoll_ctl(struct io_kiocb
*req
, unsigned int issue_flags
)
4459 #if defined(CONFIG_EPOLL)
4460 struct io_epoll
*ie
= &req
->epoll
;
4462 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4464 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4465 if (force_nonblock
&& ret
== -EAGAIN
)
4470 __io_req_complete(req
, issue_flags
, ret
, 0);
4477 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4479 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4480 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
|| sqe
->splice_fd_in
)
4482 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4485 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4486 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4487 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4494 static int io_madvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4496 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4497 struct io_madvise
*ma
= &req
->madvise
;
4500 if (issue_flags
& IO_URING_F_NONBLOCK
)
4503 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4506 io_req_complete(req
, ret
);
4513 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4515 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
|| sqe
->splice_fd_in
)
4517 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4520 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4521 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4522 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4526 static int io_fadvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4528 struct io_fadvise
*fa
= &req
->fadvise
;
4531 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4532 switch (fa
->advice
) {
4533 case POSIX_FADV_NORMAL
:
4534 case POSIX_FADV_RANDOM
:
4535 case POSIX_FADV_SEQUENTIAL
:
4542 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4545 __io_req_complete(req
, issue_flags
, ret
, 0);
4549 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4551 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4553 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
4555 if (req
->flags
& REQ_F_FIXED_FILE
)
4558 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4559 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4560 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4561 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4562 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4567 static int io_statx(struct io_kiocb
*req
, unsigned int issue_flags
)
4569 struct io_statx
*ctx
= &req
->statx
;
4572 if (issue_flags
& IO_URING_F_NONBLOCK
)
4575 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4580 io_req_complete(req
, ret
);
4584 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4586 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4588 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4589 sqe
->rw_flags
|| sqe
->buf_index
)
4591 if (req
->flags
& REQ_F_FIXED_FILE
)
4594 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4595 req
->close
.file_slot
= READ_ONCE(sqe
->file_index
);
4596 if (req
->close
.file_slot
&& req
->close
.fd
)
4602 static int io_close(struct io_kiocb
*req
, unsigned int issue_flags
)
4604 struct files_struct
*files
= current
->files
;
4605 struct io_close
*close
= &req
->close
;
4606 struct fdtable
*fdt
;
4607 struct file
*file
= NULL
;
4610 if (req
->close
.file_slot
) {
4611 ret
= io_close_fixed(req
, issue_flags
);
4615 spin_lock(&files
->file_lock
);
4616 fdt
= files_fdtable(files
);
4617 if (close
->fd
>= fdt
->max_fds
) {
4618 spin_unlock(&files
->file_lock
);
4621 file
= fdt
->fd
[close
->fd
];
4622 if (!file
|| file
->f_op
== &io_uring_fops
) {
4623 spin_unlock(&files
->file_lock
);
4628 /* if the file has a flush method, be safe and punt to async */
4629 if (file
->f_op
->flush
&& (issue_flags
& IO_URING_F_NONBLOCK
)) {
4630 spin_unlock(&files
->file_lock
);
4634 ret
= __close_fd_get_file(close
->fd
, &file
);
4635 spin_unlock(&files
->file_lock
);
4642 /* No ->flush() or already async, safely close from here */
4643 ret
= filp_close(file
, current
->files
);
4649 __io_req_complete(req
, issue_flags
, ret
, 0);
4653 static int io_sfr_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4655 struct io_ring_ctx
*ctx
= req
->ctx
;
4657 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4659 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
||
4663 req
->sync
.off
= READ_ONCE(sqe
->off
);
4664 req
->sync
.len
= READ_ONCE(sqe
->len
);
4665 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4669 static int io_sync_file_range(struct io_kiocb
*req
, unsigned int issue_flags
)
4673 /* sync_file_range always requires a blocking context */
4674 if (issue_flags
& IO_URING_F_NONBLOCK
)
4677 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4681 io_req_complete(req
, ret
);
4685 #if defined(CONFIG_NET)
4686 static int io_setup_async_msg(struct io_kiocb
*req
,
4687 struct io_async_msghdr
*kmsg
)
4689 struct io_async_msghdr
*async_msg
= req
->async_data
;
4693 if (io_alloc_async_data(req
)) {
4694 kfree(kmsg
->free_iov
);
4697 async_msg
= req
->async_data
;
4698 req
->flags
|= REQ_F_NEED_CLEANUP
;
4699 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4700 async_msg
->msg
.msg_name
= &async_msg
->addr
;
4701 /* if were using fast_iov, set it to the new one */
4702 if (!async_msg
->free_iov
)
4703 async_msg
->msg
.msg_iter
.iov
= async_msg
->fast_iov
;
4708 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4709 struct io_async_msghdr
*iomsg
)
4711 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4712 iomsg
->free_iov
= iomsg
->fast_iov
;
4713 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4714 req
->sr_msg
.msg_flags
, &iomsg
->free_iov
);
4717 static int io_sendmsg_prep_async(struct io_kiocb
*req
)
4721 ret
= io_sendmsg_copy_hdr(req
, req
->async_data
);
4723 req
->flags
|= REQ_F_NEED_CLEANUP
;
4727 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4729 struct io_sr_msg
*sr
= &req
->sr_msg
;
4731 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4734 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4735 sr
->len
= READ_ONCE(sqe
->len
);
4736 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
) | MSG_NOSIGNAL
;
4737 if (sr
->msg_flags
& MSG_DONTWAIT
)
4738 req
->flags
|= REQ_F_NOWAIT
;
4740 #ifdef CONFIG_COMPAT
4741 if (req
->ctx
->compat
)
4742 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4747 static int io_sendmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4749 struct io_async_msghdr iomsg
, *kmsg
;
4750 struct socket
*sock
;
4755 sock
= sock_from_file(req
->file
);
4756 if (unlikely(!sock
))
4759 kmsg
= req
->async_data
;
4761 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4767 flags
= req
->sr_msg
.msg_flags
;
4768 if (issue_flags
& IO_URING_F_NONBLOCK
)
4769 flags
|= MSG_DONTWAIT
;
4770 if (flags
& MSG_WAITALL
)
4771 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
4773 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4774 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4775 return io_setup_async_msg(req
, kmsg
);
4776 if (ret
== -ERESTARTSYS
)
4779 /* fast path, check for non-NULL to avoid function call */
4781 kfree(kmsg
->free_iov
);
4782 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4785 __io_req_complete(req
, issue_flags
, ret
, 0);
4789 static int io_send(struct io_kiocb
*req
, unsigned int issue_flags
)
4791 struct io_sr_msg
*sr
= &req
->sr_msg
;
4794 struct socket
*sock
;
4799 sock
= sock_from_file(req
->file
);
4800 if (unlikely(!sock
))
4803 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4807 msg
.msg_name
= NULL
;
4808 msg
.msg_control
= NULL
;
4809 msg
.msg_controllen
= 0;
4810 msg
.msg_namelen
= 0;
4812 flags
= req
->sr_msg
.msg_flags
;
4813 if (issue_flags
& IO_URING_F_NONBLOCK
)
4814 flags
|= MSG_DONTWAIT
;
4815 if (flags
& MSG_WAITALL
)
4816 min_ret
= iov_iter_count(&msg
.msg_iter
);
4818 msg
.msg_flags
= flags
;
4819 ret
= sock_sendmsg(sock
, &msg
);
4820 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4822 if (ret
== -ERESTARTSYS
)
4827 __io_req_complete(req
, issue_flags
, ret
, 0);
4831 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4832 struct io_async_msghdr
*iomsg
)
4834 struct io_sr_msg
*sr
= &req
->sr_msg
;
4835 struct iovec __user
*uiov
;
4839 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4840 &iomsg
->uaddr
, &uiov
, &iov_len
);
4844 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4847 if (copy_from_user(iomsg
->fast_iov
, uiov
, sizeof(*uiov
)))
4849 sr
->len
= iomsg
->fast_iov
[0].iov_len
;
4850 iomsg
->free_iov
= NULL
;
4852 iomsg
->free_iov
= iomsg
->fast_iov
;
4853 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4854 &iomsg
->free_iov
, &iomsg
->msg
.msg_iter
,
4863 #ifdef CONFIG_COMPAT
4864 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4865 struct io_async_msghdr
*iomsg
)
4867 struct io_sr_msg
*sr
= &req
->sr_msg
;
4868 struct compat_iovec __user
*uiov
;
4873 ret
= __get_compat_msghdr(&iomsg
->msg
, sr
->umsg_compat
, &iomsg
->uaddr
,
4878 uiov
= compat_ptr(ptr
);
4879 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4880 compat_ssize_t clen
;
4884 if (!access_ok(uiov
, sizeof(*uiov
)))
4886 if (__get_user(clen
, &uiov
->iov_len
))
4891 iomsg
->free_iov
= NULL
;
4893 iomsg
->free_iov
= iomsg
->fast_iov
;
4894 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4895 UIO_FASTIOV
, &iomsg
->free_iov
,
4896 &iomsg
->msg
.msg_iter
, true);
4905 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4906 struct io_async_msghdr
*iomsg
)
4908 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4910 #ifdef CONFIG_COMPAT
4911 if (req
->ctx
->compat
)
4912 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4915 return __io_recvmsg_copy_hdr(req
, iomsg
);
4918 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4921 struct io_sr_msg
*sr
= &req
->sr_msg
;
4922 struct io_buffer
*kbuf
;
4924 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4929 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4933 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4935 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4938 static int io_recvmsg_prep_async(struct io_kiocb
*req
)
4942 ret
= io_recvmsg_copy_hdr(req
, req
->async_data
);
4944 req
->flags
|= REQ_F_NEED_CLEANUP
;
4948 static int io_recvmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4950 struct io_sr_msg
*sr
= &req
->sr_msg
;
4952 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4955 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4956 sr
->len
= READ_ONCE(sqe
->len
);
4957 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4958 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
) | MSG_NOSIGNAL
;
4959 if (sr
->msg_flags
& MSG_DONTWAIT
)
4960 req
->flags
|= REQ_F_NOWAIT
;
4962 #ifdef CONFIG_COMPAT
4963 if (req
->ctx
->compat
)
4964 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4969 static int io_recvmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4971 struct io_async_msghdr iomsg
, *kmsg
;
4972 struct socket
*sock
;
4973 struct io_buffer
*kbuf
;
4976 int ret
, cflags
= 0;
4977 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4979 sock
= sock_from_file(req
->file
);
4980 if (unlikely(!sock
))
4983 kmsg
= req
->async_data
;
4985 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4991 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4992 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4994 return PTR_ERR(kbuf
);
4995 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4996 kmsg
->fast_iov
[0].iov_len
= req
->sr_msg
.len
;
4997 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->fast_iov
,
4998 1, req
->sr_msg
.len
);
5001 flags
= req
->sr_msg
.msg_flags
;
5003 flags
|= MSG_DONTWAIT
;
5004 if (flags
& MSG_WAITALL
)
5005 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
5007 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
5008 kmsg
->uaddr
, flags
);
5009 if (force_nonblock
&& ret
== -EAGAIN
)
5010 return io_setup_async_msg(req
, kmsg
);
5011 if (ret
== -ERESTARTSYS
)
5014 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5015 cflags
= io_put_recv_kbuf(req
);
5016 /* fast path, check for non-NULL to avoid function call */
5018 kfree(kmsg
->free_iov
);
5019 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5020 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (kmsg
->msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
5022 __io_req_complete(req
, issue_flags
, ret
, cflags
);
5026 static int io_recv(struct io_kiocb
*req
, unsigned int issue_flags
)
5028 struct io_buffer
*kbuf
;
5029 struct io_sr_msg
*sr
= &req
->sr_msg
;
5031 void __user
*buf
= sr
->buf
;
5032 struct socket
*sock
;
5036 int ret
, cflags
= 0;
5037 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
5039 sock
= sock_from_file(req
->file
);
5040 if (unlikely(!sock
))
5043 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
5044 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
5046 return PTR_ERR(kbuf
);
5047 buf
= u64_to_user_ptr(kbuf
->addr
);
5050 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
5054 msg
.msg_name
= NULL
;
5055 msg
.msg_control
= NULL
;
5056 msg
.msg_controllen
= 0;
5057 msg
.msg_namelen
= 0;
5058 msg
.msg_iocb
= NULL
;
5061 flags
= req
->sr_msg
.msg_flags
;
5063 flags
|= MSG_DONTWAIT
;
5064 if (flags
& MSG_WAITALL
)
5065 min_ret
= iov_iter_count(&msg
.msg_iter
);
5067 ret
= sock_recvmsg(sock
, &msg
, flags
);
5068 if (force_nonblock
&& ret
== -EAGAIN
)
5070 if (ret
== -ERESTARTSYS
)
5073 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5074 cflags
= io_put_recv_kbuf(req
);
5075 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
5077 __io_req_complete(req
, issue_flags
, ret
, cflags
);
5081 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5083 struct io_accept
*accept
= &req
->accept
;
5085 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5087 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
5090 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
5091 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
5092 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
5093 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
5095 accept
->file_slot
= READ_ONCE(sqe
->file_index
);
5096 if (accept
->file_slot
&& ((req
->open
.how
.flags
& O_CLOEXEC
) ||
5097 (accept
->flags
& SOCK_CLOEXEC
)))
5099 if (accept
->flags
& ~(SOCK_CLOEXEC
| SOCK_NONBLOCK
))
5101 if (SOCK_NONBLOCK
!= O_NONBLOCK
&& (accept
->flags
& SOCK_NONBLOCK
))
5102 accept
->flags
= (accept
->flags
& ~SOCK_NONBLOCK
) | O_NONBLOCK
;
5106 static int io_accept(struct io_kiocb
*req
, unsigned int issue_flags
)
5108 struct io_accept
*accept
= &req
->accept
;
5109 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
5110 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
5111 bool fixed
= !!accept
->file_slot
;
5115 if (req
->file
->f_flags
& O_NONBLOCK
)
5116 req
->flags
|= REQ_F_NOWAIT
;
5119 fd
= __get_unused_fd_flags(accept
->flags
, accept
->nofile
);
5120 if (unlikely(fd
< 0))
5123 file
= do_accept(req
->file
, file_flags
, accept
->addr
, accept
->addr_len
,
5128 ret
= PTR_ERR(file
);
5129 if (ret
== -EAGAIN
&& force_nonblock
)
5131 if (ret
== -ERESTARTSYS
)
5134 } else if (!fixed
) {
5135 fd_install(fd
, file
);
5138 ret
= io_install_fixed_file(req
, file
, issue_flags
,
5139 accept
->file_slot
- 1);
5141 __io_req_complete(req
, issue_flags
, ret
, 0);
5145 static int io_connect_prep_async(struct io_kiocb
*req
)
5147 struct io_async_connect
*io
= req
->async_data
;
5148 struct io_connect
*conn
= &req
->connect
;
5150 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
, &io
->address
);
5153 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5155 struct io_connect
*conn
= &req
->connect
;
5157 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5159 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
||
5163 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
5164 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
5168 static int io_connect(struct io_kiocb
*req
, unsigned int issue_flags
)
5170 struct io_async_connect __io
, *io
;
5171 unsigned file_flags
;
5173 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
5175 if (req
->async_data
) {
5176 io
= req
->async_data
;
5178 ret
= move_addr_to_kernel(req
->connect
.addr
,
5179 req
->connect
.addr_len
,
5186 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
5188 ret
= __sys_connect_file(req
->file
, &io
->address
,
5189 req
->connect
.addr_len
, file_flags
);
5190 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
5191 if (req
->async_data
)
5193 if (io_alloc_async_data(req
)) {
5197 memcpy(req
->async_data
, &__io
, sizeof(__io
));
5200 if (ret
== -ERESTARTSYS
)
5205 __io_req_complete(req
, issue_flags
, ret
, 0);
5208 #else /* !CONFIG_NET */
5209 #define IO_NETOP_FN(op) \
5210 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
5212 return -EOPNOTSUPP; \
5215 #define IO_NETOP_PREP(op) \
5217 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
5219 return -EOPNOTSUPP; \
5222 #define IO_NETOP_PREP_ASYNC(op) \
5224 static int io_##op##_prep_async(struct io_kiocb *req) \
5226 return -EOPNOTSUPP; \
5229 IO_NETOP_PREP_ASYNC(sendmsg
);
5230 IO_NETOP_PREP_ASYNC(recvmsg
);
5231 IO_NETOP_PREP_ASYNC(connect
);
5232 IO_NETOP_PREP(accept
);
5235 #endif /* CONFIG_NET */
5237 struct io_poll_table
{
5238 struct poll_table_struct pt
;
5239 struct io_kiocb
*req
;
5244 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
5245 __poll_t mask
, io_req_tw_func_t func
)
5247 /* for instances that support it check for an event match first: */
5248 if (mask
&& !(mask
& poll
->events
))
5251 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
5253 list_del_init(&poll
->wait
.entry
);
5256 req
->io_task_work
.func
= func
;
5259 * If this fails, then the task is exiting. When a task exits, the
5260 * work gets canceled, so just cancel this request as well instead
5261 * of executing it. We can't safely execute it anyway, as we may not
5262 * have the needed state needed for it anyway.
5264 io_req_task_work_add(req
);
5268 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
5269 __acquires(&req
->ctx
->completion_lock
)
5271 struct io_ring_ctx
*ctx
= req
->ctx
;
5273 /* req->task == current here, checking PF_EXITING is safe */
5274 if (unlikely(req
->task
->flags
& PF_EXITING
))
5275 WRITE_ONCE(poll
->canceled
, true);
5277 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5278 struct poll_table_struct pt
= { ._key
= poll
->events
};
5280 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
5283 spin_lock(&ctx
->completion_lock
);
5284 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5285 add_wait_queue(poll
->head
, &poll
->wait
);
5292 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
5294 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
5295 if (req
->opcode
== IORING_OP_POLL_ADD
)
5296 return req
->async_data
;
5297 return req
->apoll
->double_poll
;
5300 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
5302 if (req
->opcode
== IORING_OP_POLL_ADD
)
5304 return &req
->apoll
->poll
;
5307 static void io_poll_remove_double(struct io_kiocb
*req
)
5308 __must_hold(&req
->ctx
->completion_lock
)
5310 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
5312 lockdep_assert_held(&req
->ctx
->completion_lock
);
5314 if (poll
&& poll
->head
) {
5315 struct wait_queue_head
*head
= poll
->head
;
5317 spin_lock_irq(&head
->lock
);
5318 list_del_init(&poll
->wait
.entry
);
5319 if (poll
->wait
.private)
5322 spin_unlock_irq(&head
->lock
);
5326 static bool __io_poll_complete(struct io_kiocb
*req
, __poll_t mask
)
5327 __must_hold(&req
->ctx
->completion_lock
)
5329 struct io_ring_ctx
*ctx
= req
->ctx
;
5330 unsigned flags
= IORING_CQE_F_MORE
;
5333 if (READ_ONCE(req
->poll
.canceled
)) {
5335 req
->poll
.events
|= EPOLLONESHOT
;
5337 error
= mangle_poll(mask
);
5339 if (req
->poll
.events
& EPOLLONESHOT
)
5341 if (!io_cqring_fill_event(ctx
, req
->user_data
, error
, flags
)) {
5342 req
->poll
.events
|= EPOLLONESHOT
;
5345 if (flags
& IORING_CQE_F_MORE
)
5348 return !(flags
& IORING_CQE_F_MORE
);
5351 static inline bool io_poll_complete(struct io_kiocb
*req
, __poll_t mask
)
5352 __must_hold(&req
->ctx
->completion_lock
)
5356 done
= __io_poll_complete(req
, mask
);
5357 io_commit_cqring(req
->ctx
);
5361 static void io_poll_task_func(struct io_kiocb
*req
, bool *locked
)
5363 struct io_ring_ctx
*ctx
= req
->ctx
;
5364 struct io_kiocb
*nxt
;
5366 if (io_poll_rewait(req
, &req
->poll
)) {
5367 spin_unlock(&ctx
->completion_lock
);
5371 if (req
->poll
.done
) {
5372 spin_unlock(&ctx
->completion_lock
);
5375 done
= __io_poll_complete(req
, req
->result
);
5377 io_poll_remove_double(req
);
5378 hash_del(&req
->hash_node
);
5379 req
->poll
.done
= true;
5382 add_wait_queue(req
->poll
.head
, &req
->poll
.wait
);
5384 io_commit_cqring(ctx
);
5385 spin_unlock(&ctx
->completion_lock
);
5386 io_cqring_ev_posted(ctx
);
5389 nxt
= io_put_req_find_next(req
);
5391 io_req_task_submit(nxt
, locked
);
5396 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
5397 int sync
, void *key
)
5399 struct io_kiocb
*req
= wait
->private;
5400 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
5401 __poll_t mask
= key_to_poll(key
);
5402 unsigned long flags
;
5404 /* for instances that support it check for an event match first: */
5405 if (mask
&& !(mask
& poll
->events
))
5407 if (!(poll
->events
& EPOLLONESHOT
))
5408 return poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5410 list_del_init(&wait
->entry
);
5415 spin_lock_irqsave(&poll
->head
->lock
, flags
);
5416 done
= list_empty(&poll
->wait
.entry
);
5418 list_del_init(&poll
->wait
.entry
);
5419 /* make sure double remove sees this as being gone */
5420 wait
->private = NULL
;
5421 spin_unlock_irqrestore(&poll
->head
->lock
, flags
);
5423 /* use wait func handler, so it matches the rq type */
5424 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5431 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
5432 wait_queue_func_t wake_func
)
5436 poll
->canceled
= false;
5437 #define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
5438 /* mask in events that we always want/need */
5439 poll
->events
= events
| IO_POLL_UNMASK
;
5440 INIT_LIST_HEAD(&poll
->wait
.entry
);
5441 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5444 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5445 struct wait_queue_head
*head
,
5446 struct io_poll_iocb
**poll_ptr
)
5448 struct io_kiocb
*req
= pt
->req
;
5451 * The file being polled uses multiple waitqueues for poll handling
5452 * (e.g. one for read, one for write). Setup a separate io_poll_iocb
5455 if (unlikely(pt
->nr_entries
)) {
5456 struct io_poll_iocb
*poll_one
= poll
;
5458 /* double add on the same waitqueue head, ignore */
5459 if (poll_one
->head
== head
)
5461 /* already have a 2nd entry, fail a third attempt */
5463 if ((*poll_ptr
)->head
== head
)
5465 pt
->error
= -EINVAL
;
5469 * Can't handle multishot for double wait for now, turn it
5470 * into one-shot mode.
5472 if (!(poll_one
->events
& EPOLLONESHOT
))
5473 poll_one
->events
|= EPOLLONESHOT
;
5474 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5476 pt
->error
= -ENOMEM
;
5479 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5481 poll
->wait
.private = req
;
5488 if (poll
->events
& EPOLLEXCLUSIVE
)
5489 add_wait_queue_exclusive(head
, &poll
->wait
);
5491 add_wait_queue(head
, &poll
->wait
);
5494 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5495 struct poll_table_struct
*p
)
5497 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5498 struct async_poll
*apoll
= pt
->req
->apoll
;
5500 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5503 static void io_async_task_func(struct io_kiocb
*req
, bool *locked
)
5505 struct async_poll
*apoll
= req
->apoll
;
5506 struct io_ring_ctx
*ctx
= req
->ctx
;
5508 trace_io_uring_task_run(req
->ctx
, req
, req
->opcode
, req
->user_data
);
5510 if (io_poll_rewait(req
, &apoll
->poll
)) {
5511 spin_unlock(&ctx
->completion_lock
);
5515 hash_del(&req
->hash_node
);
5516 io_poll_remove_double(req
);
5517 apoll
->poll
.done
= true;
5518 spin_unlock(&ctx
->completion_lock
);
5520 if (!READ_ONCE(apoll
->poll
.canceled
))
5521 io_req_task_submit(req
, locked
);
5523 io_req_complete_failed(req
, -ECANCELED
);
5526 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5529 struct io_kiocb
*req
= wait
->private;
5530 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5532 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5535 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5538 static void io_poll_req_insert(struct io_kiocb
*req
)
5540 struct io_ring_ctx
*ctx
= req
->ctx
;
5541 struct hlist_head
*list
;
5543 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5544 hlist_add_head(&req
->hash_node
, list
);
5547 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5548 struct io_poll_iocb
*poll
,
5549 struct io_poll_table
*ipt
, __poll_t mask
,
5550 wait_queue_func_t wake_func
)
5551 __acquires(&ctx
->completion_lock
)
5553 struct io_ring_ctx
*ctx
= req
->ctx
;
5554 bool cancel
= false;
5556 INIT_HLIST_NODE(&req
->hash_node
);
5557 io_init_poll_iocb(poll
, mask
, wake_func
);
5558 poll
->file
= req
->file
;
5559 poll
->wait
.private = req
;
5561 ipt
->pt
._key
= mask
;
5564 ipt
->nr_entries
= 0;
5566 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5567 if (unlikely(!ipt
->nr_entries
) && !ipt
->error
)
5568 ipt
->error
= -EINVAL
;
5570 spin_lock(&ctx
->completion_lock
);
5571 if (ipt
->error
|| (mask
&& (poll
->events
& EPOLLONESHOT
)))
5572 io_poll_remove_double(req
);
5573 if (likely(poll
->head
)) {
5574 spin_lock_irq(&poll
->head
->lock
);
5575 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5581 if ((mask
&& (poll
->events
& EPOLLONESHOT
)) || ipt
->error
)
5582 list_del_init(&poll
->wait
.entry
);
5584 WRITE_ONCE(poll
->canceled
, true);
5585 else if (!poll
->done
) /* actually waiting for an event */
5586 io_poll_req_insert(req
);
5587 spin_unlock_irq(&poll
->head
->lock
);
5599 static int io_arm_poll_handler(struct io_kiocb
*req
)
5601 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5602 struct io_ring_ctx
*ctx
= req
->ctx
;
5603 struct async_poll
*apoll
;
5604 struct io_poll_table ipt
;
5605 __poll_t ret
, mask
= EPOLLONESHOT
| POLLERR
| POLLPRI
;
5608 if (!req
->file
|| !file_can_poll(req
->file
))
5609 return IO_APOLL_ABORTED
;
5610 if (req
->flags
& REQ_F_POLLED
)
5611 return IO_APOLL_ABORTED
;
5612 if (!def
->pollin
&& !def
->pollout
)
5613 return IO_APOLL_ABORTED
;
5617 mask
|= POLLIN
| POLLRDNORM
;
5619 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5620 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5621 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5625 mask
|= POLLOUT
| POLLWRNORM
;
5628 /* if we can't nonblock try, then no point in arming a poll handler */
5629 if (!io_file_supports_nowait(req
, rw
))
5630 return IO_APOLL_ABORTED
;
5632 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5633 if (unlikely(!apoll
))
5634 return IO_APOLL_ABORTED
;
5635 apoll
->double_poll
= NULL
;
5637 req
->flags
|= REQ_F_POLLED
;
5638 ipt
.pt
._qproc
= io_async_queue_proc
;
5639 io_req_set_refcount(req
);
5641 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5643 spin_unlock(&ctx
->completion_lock
);
5644 if (ret
|| ipt
.error
)
5645 return ret
? IO_APOLL_READY
: IO_APOLL_ABORTED
;
5647 trace_io_uring_poll_arm(ctx
, req
, req
->opcode
, req
->user_data
,
5648 mask
, apoll
->poll
.events
);
5652 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5653 struct io_poll_iocb
*poll
, bool do_cancel
)
5654 __must_hold(&req
->ctx
->completion_lock
)
5656 bool do_complete
= false;
5660 spin_lock_irq(&poll
->head
->lock
);
5662 WRITE_ONCE(poll
->canceled
, true);
5663 if (!list_empty(&poll
->wait
.entry
)) {
5664 list_del_init(&poll
->wait
.entry
);
5667 spin_unlock_irq(&poll
->head
->lock
);
5668 hash_del(&req
->hash_node
);
5672 static bool io_poll_remove_one(struct io_kiocb
*req
)
5673 __must_hold(&req
->ctx
->completion_lock
)
5677 io_poll_remove_double(req
);
5678 do_complete
= __io_poll_remove_one(req
, io_poll_get_single(req
), true);
5681 io_cqring_fill_event(req
->ctx
, req
->user_data
, -ECANCELED
, 0);
5682 io_commit_cqring(req
->ctx
);
5684 io_put_req_deferred(req
);
5690 * Returns true if we found and killed one or more poll requests
5692 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5695 struct hlist_node
*tmp
;
5696 struct io_kiocb
*req
;
5699 spin_lock(&ctx
->completion_lock
);
5700 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5701 struct hlist_head
*list
;
5703 list
= &ctx
->cancel_hash
[i
];
5704 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5705 if (io_match_task(req
, tsk
, cancel_all
))
5706 posted
+= io_poll_remove_one(req
);
5709 spin_unlock(&ctx
->completion_lock
);
5712 io_cqring_ev_posted(ctx
);
5717 static struct io_kiocb
*io_poll_find(struct io_ring_ctx
*ctx
, __u64 sqe_addr
,
5719 __must_hold(&ctx
->completion_lock
)
5721 struct hlist_head
*list
;
5722 struct io_kiocb
*req
;
5724 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5725 hlist_for_each_entry(req
, list
, hash_node
) {
5726 if (sqe_addr
!= req
->user_data
)
5728 if (poll_only
&& req
->opcode
!= IORING_OP_POLL_ADD
)
5735 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
,
5737 __must_hold(&ctx
->completion_lock
)
5739 struct io_kiocb
*req
;
5741 req
= io_poll_find(ctx
, sqe_addr
, poll_only
);
5744 if (io_poll_remove_one(req
))
5750 static __poll_t
io_poll_parse_events(const struct io_uring_sqe
*sqe
,
5755 events
= READ_ONCE(sqe
->poll32_events
);
5757 events
= swahw32(events
);
5759 if (!(flags
& IORING_POLL_ADD_MULTI
))
5760 events
|= EPOLLONESHOT
;
5761 return demangle_poll(events
) | (events
& (EPOLLEXCLUSIVE
|EPOLLONESHOT
));
5764 static int io_poll_update_prep(struct io_kiocb
*req
,
5765 const struct io_uring_sqe
*sqe
)
5767 struct io_poll_update
*upd
= &req
->poll_update
;
5770 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5772 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
5774 flags
= READ_ONCE(sqe
->len
);
5775 if (flags
& ~(IORING_POLL_UPDATE_EVENTS
| IORING_POLL_UPDATE_USER_DATA
|
5776 IORING_POLL_ADD_MULTI
))
5778 /* meaningless without update */
5779 if (flags
== IORING_POLL_ADD_MULTI
)
5782 upd
->old_user_data
= READ_ONCE(sqe
->addr
);
5783 upd
->update_events
= flags
& IORING_POLL_UPDATE_EVENTS
;
5784 upd
->update_user_data
= flags
& IORING_POLL_UPDATE_USER_DATA
;
5786 upd
->new_user_data
= READ_ONCE(sqe
->off
);
5787 if (!upd
->update_user_data
&& upd
->new_user_data
)
5789 if (upd
->update_events
)
5790 upd
->events
= io_poll_parse_events(sqe
, flags
);
5791 else if (sqe
->poll32_events
)
5797 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5800 struct io_kiocb
*req
= wait
->private;
5801 struct io_poll_iocb
*poll
= &req
->poll
;
5803 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5806 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5807 struct poll_table_struct
*p
)
5809 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5811 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5814 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5816 struct io_poll_iocb
*poll
= &req
->poll
;
5819 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5821 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
|| sqe
->addr
)
5823 flags
= READ_ONCE(sqe
->len
);
5824 if (flags
& ~IORING_POLL_ADD_MULTI
)
5827 io_req_set_refcount(req
);
5828 poll
->events
= io_poll_parse_events(sqe
, flags
);
5832 static int io_poll_add(struct io_kiocb
*req
, unsigned int issue_flags
)
5834 struct io_poll_iocb
*poll
= &req
->poll
;
5835 struct io_ring_ctx
*ctx
= req
->ctx
;
5836 struct io_poll_table ipt
;
5840 ipt
.pt
._qproc
= io_poll_queue_proc
;
5842 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5845 if (mask
) { /* no async, we'd stolen it */
5847 done
= io_poll_complete(req
, mask
);
5849 spin_unlock(&ctx
->completion_lock
);
5852 io_cqring_ev_posted(ctx
);
5859 static int io_poll_update(struct io_kiocb
*req
, unsigned int issue_flags
)
5861 struct io_ring_ctx
*ctx
= req
->ctx
;
5862 struct io_kiocb
*preq
;
5866 spin_lock(&ctx
->completion_lock
);
5867 preq
= io_poll_find(ctx
, req
->poll_update
.old_user_data
, true);
5873 if (!req
->poll_update
.update_events
&& !req
->poll_update
.update_user_data
) {
5875 ret
= io_poll_remove_one(preq
) ? 0 : -EALREADY
;
5880 * Don't allow racy completion with singleshot, as we cannot safely
5881 * update those. For multishot, if we're racing with completion, just
5882 * let completion re-add it.
5884 completing
= !__io_poll_remove_one(preq
, &preq
->poll
, false);
5885 if (completing
&& (preq
->poll
.events
& EPOLLONESHOT
)) {
5889 /* we now have a detached poll request. reissue. */
5893 spin_unlock(&ctx
->completion_lock
);
5895 io_req_complete(req
, ret
);
5898 /* only mask one event flags, keep behavior flags */
5899 if (req
->poll_update
.update_events
) {
5900 preq
->poll
.events
&= ~0xffff;
5901 preq
->poll
.events
|= req
->poll_update
.events
& 0xffff;
5902 preq
->poll
.events
|= IO_POLL_UNMASK
;
5904 if (req
->poll_update
.update_user_data
)
5905 preq
->user_data
= req
->poll_update
.new_user_data
;
5906 spin_unlock(&ctx
->completion_lock
);
5908 /* complete update request, we're done with it */
5909 io_req_complete(req
, ret
);
5912 ret
= io_poll_add(preq
, issue_flags
);
5915 io_req_complete(preq
, ret
);
5921 static void io_req_task_timeout(struct io_kiocb
*req
, bool *locked
)
5924 io_req_complete_post(req
, -ETIME
, 0);
5927 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5929 struct io_timeout_data
*data
= container_of(timer
,
5930 struct io_timeout_data
, timer
);
5931 struct io_kiocb
*req
= data
->req
;
5932 struct io_ring_ctx
*ctx
= req
->ctx
;
5933 unsigned long flags
;
5935 spin_lock_irqsave(&ctx
->timeout_lock
, flags
);
5936 list_del_init(&req
->timeout
.list
);
5937 atomic_set(&req
->ctx
->cq_timeouts
,
5938 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5939 spin_unlock_irqrestore(&ctx
->timeout_lock
, flags
);
5941 req
->io_task_work
.func
= io_req_task_timeout
;
5942 io_req_task_work_add(req
);
5943 return HRTIMER_NORESTART
;
5946 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5948 __must_hold(&ctx
->timeout_lock
)
5950 struct io_timeout_data
*io
;
5951 struct io_kiocb
*req
;
5954 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5955 found
= user_data
== req
->user_data
;
5960 return ERR_PTR(-ENOENT
);
5962 io
= req
->async_data
;
5963 if (hrtimer_try_to_cancel(&io
->timer
) == -1)
5964 return ERR_PTR(-EALREADY
);
5965 list_del_init(&req
->timeout
.list
);
5969 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5970 __must_hold(&ctx
->completion_lock
)
5971 __must_hold(&ctx
->timeout_lock
)
5973 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5976 return PTR_ERR(req
);
5979 io_cqring_fill_event(ctx
, req
->user_data
, -ECANCELED
, 0);
5980 io_put_req_deferred(req
);
5984 static clockid_t
io_timeout_get_clock(struct io_timeout_data
*data
)
5986 switch (data
->flags
& IORING_TIMEOUT_CLOCK_MASK
) {
5987 case IORING_TIMEOUT_BOOTTIME
:
5988 return CLOCK_BOOTTIME
;
5989 case IORING_TIMEOUT_REALTIME
:
5990 return CLOCK_REALTIME
;
5992 /* can't happen, vetted at prep time */
5996 return CLOCK_MONOTONIC
;
6000 static int io_linked_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
6001 struct timespec64
*ts
, enum hrtimer_mode mode
)
6002 __must_hold(&ctx
->timeout_lock
)
6004 struct io_timeout_data
*io
;
6005 struct io_kiocb
*req
;
6008 list_for_each_entry(req
, &ctx
->ltimeout_list
, timeout
.list
) {
6009 found
= user_data
== req
->user_data
;
6016 io
= req
->async_data
;
6017 if (hrtimer_try_to_cancel(&io
->timer
) == -1)
6019 hrtimer_init(&io
->timer
, io_timeout_get_clock(io
), mode
);
6020 io
->timer
.function
= io_link_timeout_fn
;
6021 hrtimer_start(&io
->timer
, timespec64_to_ktime(*ts
), mode
);
6025 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
6026 struct timespec64
*ts
, enum hrtimer_mode mode
)
6027 __must_hold(&ctx
->timeout_lock
)
6029 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
6030 struct io_timeout_data
*data
;
6033 return PTR_ERR(req
);
6035 req
->timeout
.off
= 0; /* noseq */
6036 data
= req
->async_data
;
6037 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
6038 hrtimer_init(&data
->timer
, io_timeout_get_clock(data
), mode
);
6039 data
->timer
.function
= io_timeout_fn
;
6040 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
6044 static int io_timeout_remove_prep(struct io_kiocb
*req
,
6045 const struct io_uring_sqe
*sqe
)
6047 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
6049 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
6051 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
6053 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
|| sqe
->splice_fd_in
)
6056 tr
->ltimeout
= false;
6057 tr
->addr
= READ_ONCE(sqe
->addr
);
6058 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
6059 if (tr
->flags
& IORING_TIMEOUT_UPDATE_MASK
) {
6060 if (hweight32(tr
->flags
& IORING_TIMEOUT_CLOCK_MASK
) > 1)
6062 if (tr
->flags
& IORING_LINK_TIMEOUT_UPDATE
)
6063 tr
->ltimeout
= true;
6064 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE_MASK
|IORING_TIMEOUT_ABS
))
6066 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
6068 } else if (tr
->flags
) {
6069 /* timeout removal doesn't support flags */
6076 static inline enum hrtimer_mode
io_translate_timeout_mode(unsigned int flags
)
6078 return (flags
& IORING_TIMEOUT_ABS
) ? HRTIMER_MODE_ABS
6083 * Remove or update an existing timeout command
6085 static int io_timeout_remove(struct io_kiocb
*req
, unsigned int issue_flags
)
6087 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
6088 struct io_ring_ctx
*ctx
= req
->ctx
;
6091 if (!(req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
)) {
6092 spin_lock(&ctx
->completion_lock
);
6093 spin_lock_irq(&ctx
->timeout_lock
);
6094 ret
= io_timeout_cancel(ctx
, tr
->addr
);
6095 spin_unlock_irq(&ctx
->timeout_lock
);
6096 spin_unlock(&ctx
->completion_lock
);
6098 enum hrtimer_mode mode
= io_translate_timeout_mode(tr
->flags
);
6100 spin_lock_irq(&ctx
->timeout_lock
);
6102 ret
= io_linked_timeout_update(ctx
, tr
->addr
, &tr
->ts
, mode
);
6104 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
, mode
);
6105 spin_unlock_irq(&ctx
->timeout_lock
);
6110 io_req_complete_post(req
, ret
, 0);
6114 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6115 bool is_timeout_link
)
6117 struct io_timeout_data
*data
;
6119 u32 off
= READ_ONCE(sqe
->off
);
6121 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
6123 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1 ||
6126 if (off
&& is_timeout_link
)
6128 flags
= READ_ONCE(sqe
->timeout_flags
);
6129 if (flags
& ~(IORING_TIMEOUT_ABS
| IORING_TIMEOUT_CLOCK_MASK
))
6131 /* more than one clock specified is invalid, obviously */
6132 if (hweight32(flags
& IORING_TIMEOUT_CLOCK_MASK
) > 1)
6135 INIT_LIST_HEAD(&req
->timeout
.list
);
6136 req
->timeout
.off
= off
;
6137 if (unlikely(off
&& !req
->ctx
->off_timeout_used
))
6138 req
->ctx
->off_timeout_used
= true;
6140 if (!req
->async_data
&& io_alloc_async_data(req
))
6143 data
= req
->async_data
;
6145 data
->flags
= flags
;
6147 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
6150 data
->mode
= io_translate_timeout_mode(flags
);
6151 hrtimer_init(&data
->timer
, io_timeout_get_clock(data
), data
->mode
);
6153 if (is_timeout_link
) {
6154 struct io_submit_link
*link
= &req
->ctx
->submit_state
.link
;
6158 if (link
->last
->opcode
== IORING_OP_LINK_TIMEOUT
)
6160 req
->timeout
.head
= link
->last
;
6161 link
->last
->flags
|= REQ_F_ARM_LTIMEOUT
;
6166 static int io_timeout(struct io_kiocb
*req
, unsigned int issue_flags
)
6168 struct io_ring_ctx
*ctx
= req
->ctx
;
6169 struct io_timeout_data
*data
= req
->async_data
;
6170 struct list_head
*entry
;
6171 u32 tail
, off
= req
->timeout
.off
;
6173 spin_lock_irq(&ctx
->timeout_lock
);
6176 * sqe->off holds how many events that need to occur for this
6177 * timeout event to be satisfied. If it isn't set, then this is
6178 * a pure timeout request, sequence isn't used.
6180 if (io_is_timeout_noseq(req
)) {
6181 entry
= ctx
->timeout_list
.prev
;
6185 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
6186 req
->timeout
.target_seq
= tail
+ off
;
6188 /* Update the last seq here in case io_flush_timeouts() hasn't.
6189 * This is safe because ->completion_lock is held, and submissions
6190 * and completions are never mixed in the same ->completion_lock section.
6192 ctx
->cq_last_tm_flush
= tail
;
6195 * Insertion sort, ensuring the first entry in the list is always
6196 * the one we need first.
6198 list_for_each_prev(entry
, &ctx
->timeout_list
) {
6199 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
6202 if (io_is_timeout_noseq(nxt
))
6204 /* nxt.seq is behind @tail, otherwise would've been completed */
6205 if (off
>= nxt
->timeout
.target_seq
- tail
)
6209 list_add(&req
->timeout
.list
, entry
);
6210 data
->timer
.function
= io_timeout_fn
;
6211 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
6212 spin_unlock_irq(&ctx
->timeout_lock
);
6216 struct io_cancel_data
{
6217 struct io_ring_ctx
*ctx
;
6221 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
6223 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6224 struct io_cancel_data
*cd
= data
;
6226 return req
->ctx
== cd
->ctx
&& req
->user_data
== cd
->user_data
;
6229 static int io_async_cancel_one(struct io_uring_task
*tctx
, u64 user_data
,
6230 struct io_ring_ctx
*ctx
)
6232 struct io_cancel_data data
= { .ctx
= ctx
, .user_data
= user_data
, };
6233 enum io_wq_cancel cancel_ret
;
6236 if (!tctx
|| !tctx
->io_wq
)
6239 cancel_ret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_cb
, &data
, false);
6240 switch (cancel_ret
) {
6241 case IO_WQ_CANCEL_OK
:
6244 case IO_WQ_CANCEL_RUNNING
:
6247 case IO_WQ_CANCEL_NOTFOUND
:
6255 static int io_try_cancel_userdata(struct io_kiocb
*req
, u64 sqe_addr
)
6257 struct io_ring_ctx
*ctx
= req
->ctx
;
6260 WARN_ON_ONCE(!io_wq_current_is_worker() && req
->task
!= current
);
6262 ret
= io_async_cancel_one(req
->task
->io_uring
, sqe_addr
, ctx
);
6266 spin_lock(&ctx
->completion_lock
);
6267 spin_lock_irq(&ctx
->timeout_lock
);
6268 ret
= io_timeout_cancel(ctx
, sqe_addr
);
6269 spin_unlock_irq(&ctx
->timeout_lock
);
6272 ret
= io_poll_cancel(ctx
, sqe_addr
, false);
6274 spin_unlock(&ctx
->completion_lock
);
6278 static int io_async_cancel_prep(struct io_kiocb
*req
,
6279 const struct io_uring_sqe
*sqe
)
6281 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
6283 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
6285 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
||
6289 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
6293 static int io_async_cancel(struct io_kiocb
*req
, unsigned int issue_flags
)
6295 struct io_ring_ctx
*ctx
= req
->ctx
;
6296 u64 sqe_addr
= req
->cancel
.addr
;
6297 struct io_tctx_node
*node
;
6300 ret
= io_try_cancel_userdata(req
, sqe_addr
);
6304 /* slow path, try all io-wq's */
6305 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
6307 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
6308 struct io_uring_task
*tctx
= node
->task
->io_uring
;
6310 ret
= io_async_cancel_one(tctx
, req
->cancel
.addr
, ctx
);
6314 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
6318 io_req_complete_post(req
, ret
, 0);
6322 static int io_rsrc_update_prep(struct io_kiocb
*req
,
6323 const struct io_uring_sqe
*sqe
)
6325 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
6327 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->splice_fd_in
)
6330 req
->rsrc_update
.offset
= READ_ONCE(sqe
->off
);
6331 req
->rsrc_update
.nr_args
= READ_ONCE(sqe
->len
);
6332 if (!req
->rsrc_update
.nr_args
)
6334 req
->rsrc_update
.arg
= READ_ONCE(sqe
->addr
);
6338 static int io_files_update(struct io_kiocb
*req
, unsigned int issue_flags
)
6340 struct io_ring_ctx
*ctx
= req
->ctx
;
6341 struct io_uring_rsrc_update2 up
;
6344 up
.offset
= req
->rsrc_update
.offset
;
6345 up
.data
= req
->rsrc_update
.arg
;
6350 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
6351 ret
= __io_register_rsrc_update(ctx
, IORING_RSRC_FILE
,
6352 &up
, req
->rsrc_update
.nr_args
);
6353 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
6357 __io_req_complete(req
, issue_flags
, ret
, 0);
6361 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6363 switch (req
->opcode
) {
6366 case IORING_OP_READV
:
6367 case IORING_OP_READ_FIXED
:
6368 case IORING_OP_READ
:
6369 return io_read_prep(req
, sqe
);
6370 case IORING_OP_WRITEV
:
6371 case IORING_OP_WRITE_FIXED
:
6372 case IORING_OP_WRITE
:
6373 return io_write_prep(req
, sqe
);
6374 case IORING_OP_POLL_ADD
:
6375 return io_poll_add_prep(req
, sqe
);
6376 case IORING_OP_POLL_REMOVE
:
6377 return io_poll_update_prep(req
, sqe
);
6378 case IORING_OP_FSYNC
:
6379 return io_fsync_prep(req
, sqe
);
6380 case IORING_OP_SYNC_FILE_RANGE
:
6381 return io_sfr_prep(req
, sqe
);
6382 case IORING_OP_SENDMSG
:
6383 case IORING_OP_SEND
:
6384 return io_sendmsg_prep(req
, sqe
);
6385 case IORING_OP_RECVMSG
:
6386 case IORING_OP_RECV
:
6387 return io_recvmsg_prep(req
, sqe
);
6388 case IORING_OP_CONNECT
:
6389 return io_connect_prep(req
, sqe
);
6390 case IORING_OP_TIMEOUT
:
6391 return io_timeout_prep(req
, sqe
, false);
6392 case IORING_OP_TIMEOUT_REMOVE
:
6393 return io_timeout_remove_prep(req
, sqe
);
6394 case IORING_OP_ASYNC_CANCEL
:
6395 return io_async_cancel_prep(req
, sqe
);
6396 case IORING_OP_LINK_TIMEOUT
:
6397 return io_timeout_prep(req
, sqe
, true);
6398 case IORING_OP_ACCEPT
:
6399 return io_accept_prep(req
, sqe
);
6400 case IORING_OP_FALLOCATE
:
6401 return io_fallocate_prep(req
, sqe
);
6402 case IORING_OP_OPENAT
:
6403 return io_openat_prep(req
, sqe
);
6404 case IORING_OP_CLOSE
:
6405 return io_close_prep(req
, sqe
);
6406 case IORING_OP_FILES_UPDATE
:
6407 return io_rsrc_update_prep(req
, sqe
);
6408 case IORING_OP_STATX
:
6409 return io_statx_prep(req
, sqe
);
6410 case IORING_OP_FADVISE
:
6411 return io_fadvise_prep(req
, sqe
);
6412 case IORING_OP_MADVISE
:
6413 return io_madvise_prep(req
, sqe
);
6414 case IORING_OP_OPENAT2
:
6415 return io_openat2_prep(req
, sqe
);
6416 case IORING_OP_EPOLL_CTL
:
6417 return io_epoll_ctl_prep(req
, sqe
);
6418 case IORING_OP_SPLICE
:
6419 return io_splice_prep(req
, sqe
);
6420 case IORING_OP_PROVIDE_BUFFERS
:
6421 return io_provide_buffers_prep(req
, sqe
);
6422 case IORING_OP_REMOVE_BUFFERS
:
6423 return io_remove_buffers_prep(req
, sqe
);
6425 return io_tee_prep(req
, sqe
);
6426 case IORING_OP_SHUTDOWN
:
6427 return io_shutdown_prep(req
, sqe
);
6428 case IORING_OP_RENAMEAT
:
6429 return io_renameat_prep(req
, sqe
);
6430 case IORING_OP_UNLINKAT
:
6431 return io_unlinkat_prep(req
, sqe
);
6432 case IORING_OP_MKDIRAT
:
6433 return io_mkdirat_prep(req
, sqe
);
6434 case IORING_OP_SYMLINKAT
:
6435 return io_symlinkat_prep(req
, sqe
);
6436 case IORING_OP_LINKAT
:
6437 return io_linkat_prep(req
, sqe
);
6440 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
6445 static int io_req_prep_async(struct io_kiocb
*req
)
6447 if (!io_op_defs
[req
->opcode
].needs_async_setup
)
6449 if (WARN_ON_ONCE(req
->async_data
))
6451 if (io_alloc_async_data(req
))
6454 switch (req
->opcode
) {
6455 case IORING_OP_READV
:
6456 return io_rw_prep_async(req
, READ
);
6457 case IORING_OP_WRITEV
:
6458 return io_rw_prep_async(req
, WRITE
);
6459 case IORING_OP_SENDMSG
:
6460 return io_sendmsg_prep_async(req
);
6461 case IORING_OP_RECVMSG
:
6462 return io_recvmsg_prep_async(req
);
6463 case IORING_OP_CONNECT
:
6464 return io_connect_prep_async(req
);
6466 printk_once(KERN_WARNING
"io_uring: prep_async() bad opcode %d\n",
6471 static u32
io_get_sequence(struct io_kiocb
*req
)
6473 u32 seq
= req
->ctx
->cached_sq_head
;
6475 /* need original cached_sq_head, but it was increased for each req */
6476 io_for_each_link(req
, req
)
6481 static bool io_drain_req(struct io_kiocb
*req
)
6483 struct io_kiocb
*pos
;
6484 struct io_ring_ctx
*ctx
= req
->ctx
;
6485 struct io_defer_entry
*de
;
6489 if (req
->flags
& REQ_F_FAIL
) {
6490 io_req_complete_fail_submit(req
);
6495 * If we need to drain a request in the middle of a link, drain the
6496 * head request and the next request/link after the current link.
6497 * Considering sequential execution of links, IOSQE_IO_DRAIN will be
6498 * maintained for every request of our link.
6500 if (ctx
->drain_next
) {
6501 req
->flags
|= REQ_F_IO_DRAIN
;
6502 ctx
->drain_next
= false;
6504 /* not interested in head, start from the first linked */
6505 io_for_each_link(pos
, req
->link
) {
6506 if (pos
->flags
& REQ_F_IO_DRAIN
) {
6507 ctx
->drain_next
= true;
6508 req
->flags
|= REQ_F_IO_DRAIN
;
6513 /* Still need defer if there is pending req in defer list. */
6514 if (likely(list_empty_careful(&ctx
->defer_list
) &&
6515 !(req
->flags
& REQ_F_IO_DRAIN
))) {
6516 ctx
->drain_active
= false;
6520 seq
= io_get_sequence(req
);
6521 /* Still a chance to pass the sequence check */
6522 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
6525 ret
= io_req_prep_async(req
);
6528 io_prep_async_link(req
);
6529 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
6533 io_req_complete_failed(req
, ret
);
6537 spin_lock(&ctx
->completion_lock
);
6538 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
6539 spin_unlock(&ctx
->completion_lock
);
6541 io_queue_async_work(req
, NULL
);
6545 trace_io_uring_defer(ctx
, req
, req
->user_data
);
6548 list_add_tail(&de
->list
, &ctx
->defer_list
);
6549 spin_unlock(&ctx
->completion_lock
);
6553 static void io_clean_op(struct io_kiocb
*req
)
6555 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6556 switch (req
->opcode
) {
6557 case IORING_OP_READV
:
6558 case IORING_OP_READ_FIXED
:
6559 case IORING_OP_READ
:
6560 kfree((void *)(unsigned long)req
->rw
.addr
);
6562 case IORING_OP_RECVMSG
:
6563 case IORING_OP_RECV
:
6564 kfree(req
->sr_msg
.kbuf
);
6569 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6570 switch (req
->opcode
) {
6571 case IORING_OP_READV
:
6572 case IORING_OP_READ_FIXED
:
6573 case IORING_OP_READ
:
6574 case IORING_OP_WRITEV
:
6575 case IORING_OP_WRITE_FIXED
:
6576 case IORING_OP_WRITE
: {
6577 struct io_async_rw
*io
= req
->async_data
;
6579 kfree(io
->free_iovec
);
6582 case IORING_OP_RECVMSG
:
6583 case IORING_OP_SENDMSG
: {
6584 struct io_async_msghdr
*io
= req
->async_data
;
6586 kfree(io
->free_iov
);
6589 case IORING_OP_SPLICE
:
6591 if (!(req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
))
6592 io_put_file(req
->splice
.file_in
);
6594 case IORING_OP_OPENAT
:
6595 case IORING_OP_OPENAT2
:
6596 if (req
->open
.filename
)
6597 putname(req
->open
.filename
);
6599 case IORING_OP_RENAMEAT
:
6600 putname(req
->rename
.oldpath
);
6601 putname(req
->rename
.newpath
);
6603 case IORING_OP_UNLINKAT
:
6604 putname(req
->unlink
.filename
);
6606 case IORING_OP_MKDIRAT
:
6607 putname(req
->mkdir
.filename
);
6609 case IORING_OP_SYMLINKAT
:
6610 putname(req
->symlink
.oldpath
);
6611 putname(req
->symlink
.newpath
);
6613 case IORING_OP_LINKAT
:
6614 putname(req
->hardlink
.oldpath
);
6615 putname(req
->hardlink
.newpath
);
6619 if ((req
->flags
& REQ_F_POLLED
) && req
->apoll
) {
6620 kfree(req
->apoll
->double_poll
);
6624 if (req
->flags
& REQ_F_INFLIGHT
) {
6625 struct io_uring_task
*tctx
= req
->task
->io_uring
;
6627 atomic_dec(&tctx
->inflight_tracked
);
6629 if (req
->flags
& REQ_F_CREDS
)
6630 put_cred(req
->creds
);
6632 req
->flags
&= ~IO_REQ_CLEAN_FLAGS
;
6635 static int io_issue_sqe(struct io_kiocb
*req
, unsigned int issue_flags
)
6637 struct io_ring_ctx
*ctx
= req
->ctx
;
6638 const struct cred
*creds
= NULL
;
6641 if ((req
->flags
& REQ_F_CREDS
) && req
->creds
!= current_cred())
6642 creds
= override_creds(req
->creds
);
6644 switch (req
->opcode
) {
6646 ret
= io_nop(req
, issue_flags
);
6648 case IORING_OP_READV
:
6649 case IORING_OP_READ_FIXED
:
6650 case IORING_OP_READ
:
6651 ret
= io_read(req
, issue_flags
);
6653 case IORING_OP_WRITEV
:
6654 case IORING_OP_WRITE_FIXED
:
6655 case IORING_OP_WRITE
:
6656 ret
= io_write(req
, issue_flags
);
6658 case IORING_OP_FSYNC
:
6659 ret
= io_fsync(req
, issue_flags
);
6661 case IORING_OP_POLL_ADD
:
6662 ret
= io_poll_add(req
, issue_flags
);
6664 case IORING_OP_POLL_REMOVE
:
6665 ret
= io_poll_update(req
, issue_flags
);
6667 case IORING_OP_SYNC_FILE_RANGE
:
6668 ret
= io_sync_file_range(req
, issue_flags
);
6670 case IORING_OP_SENDMSG
:
6671 ret
= io_sendmsg(req
, issue_flags
);
6673 case IORING_OP_SEND
:
6674 ret
= io_send(req
, issue_flags
);
6676 case IORING_OP_RECVMSG
:
6677 ret
= io_recvmsg(req
, issue_flags
);
6679 case IORING_OP_RECV
:
6680 ret
= io_recv(req
, issue_flags
);
6682 case IORING_OP_TIMEOUT
:
6683 ret
= io_timeout(req
, issue_flags
);
6685 case IORING_OP_TIMEOUT_REMOVE
:
6686 ret
= io_timeout_remove(req
, issue_flags
);
6688 case IORING_OP_ACCEPT
:
6689 ret
= io_accept(req
, issue_flags
);
6691 case IORING_OP_CONNECT
:
6692 ret
= io_connect(req
, issue_flags
);
6694 case IORING_OP_ASYNC_CANCEL
:
6695 ret
= io_async_cancel(req
, issue_flags
);
6697 case IORING_OP_FALLOCATE
:
6698 ret
= io_fallocate(req
, issue_flags
);
6700 case IORING_OP_OPENAT
:
6701 ret
= io_openat(req
, issue_flags
);
6703 case IORING_OP_CLOSE
:
6704 ret
= io_close(req
, issue_flags
);
6706 case IORING_OP_FILES_UPDATE
:
6707 ret
= io_files_update(req
, issue_flags
);
6709 case IORING_OP_STATX
:
6710 ret
= io_statx(req
, issue_flags
);
6712 case IORING_OP_FADVISE
:
6713 ret
= io_fadvise(req
, issue_flags
);
6715 case IORING_OP_MADVISE
:
6716 ret
= io_madvise(req
, issue_flags
);
6718 case IORING_OP_OPENAT2
:
6719 ret
= io_openat2(req
, issue_flags
);
6721 case IORING_OP_EPOLL_CTL
:
6722 ret
= io_epoll_ctl(req
, issue_flags
);
6724 case IORING_OP_SPLICE
:
6725 ret
= io_splice(req
, issue_flags
);
6727 case IORING_OP_PROVIDE_BUFFERS
:
6728 ret
= io_provide_buffers(req
, issue_flags
);
6730 case IORING_OP_REMOVE_BUFFERS
:
6731 ret
= io_remove_buffers(req
, issue_flags
);
6734 ret
= io_tee(req
, issue_flags
);
6736 case IORING_OP_SHUTDOWN
:
6737 ret
= io_shutdown(req
, issue_flags
);
6739 case IORING_OP_RENAMEAT
:
6740 ret
= io_renameat(req
, issue_flags
);
6742 case IORING_OP_UNLINKAT
:
6743 ret
= io_unlinkat(req
, issue_flags
);
6745 case IORING_OP_MKDIRAT
:
6746 ret
= io_mkdirat(req
, issue_flags
);
6748 case IORING_OP_SYMLINKAT
:
6749 ret
= io_symlinkat(req
, issue_flags
);
6751 case IORING_OP_LINKAT
:
6752 ret
= io_linkat(req
, issue_flags
);
6760 revert_creds(creds
);
6763 /* If the op doesn't have a file, we're not polling for it */
6764 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
)
6765 io_iopoll_req_issued(req
);
6770 static struct io_wq_work
*io_wq_free_work(struct io_wq_work
*work
)
6772 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6774 req
= io_put_req_find_next(req
);
6775 return req
? &req
->work
: NULL
;
6778 static void io_wq_submit_work(struct io_wq_work
*work
)
6780 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6781 struct io_kiocb
*timeout
;
6784 /* one will be dropped by ->io_free_work() after returning to io-wq */
6785 if (!(req
->flags
& REQ_F_REFCOUNT
))
6786 __io_req_set_refcount(req
, 2);
6790 timeout
= io_prep_linked_timeout(req
);
6792 io_queue_linked_timeout(timeout
);
6794 /* either cancelled or io-wq is dying, so don't touch tctx->iowq */
6795 if (work
->flags
& IO_WQ_WORK_CANCEL
)
6800 ret
= io_issue_sqe(req
, 0);
6802 * We can get EAGAIN for polled IO even though we're
6803 * forcing a sync submission from here, since we can't
6804 * wait for request slots on the block side.
6812 /* avoid locking problems by failing it from a clean context */
6814 io_req_task_queue_fail(req
, ret
);
6817 static inline struct io_fixed_file
*io_fixed_file_slot(struct io_file_table
*table
,
6820 return &table
->files
[i
];
6823 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6826 struct io_fixed_file
*slot
= io_fixed_file_slot(&ctx
->file_table
, index
);
6828 return (struct file
*) (slot
->file_ptr
& FFS_MASK
);
6831 static void io_fixed_file_set(struct io_fixed_file
*file_slot
, struct file
*file
)
6833 unsigned long file_ptr
= (unsigned long) file
;
6835 if (__io_file_supports_nowait(file
, READ
))
6836 file_ptr
|= FFS_ASYNC_READ
;
6837 if (__io_file_supports_nowait(file
, WRITE
))
6838 file_ptr
|= FFS_ASYNC_WRITE
;
6839 if (S_ISREG(file_inode(file
)->i_mode
))
6840 file_ptr
|= FFS_ISREG
;
6841 file_slot
->file_ptr
= file_ptr
;
6844 static inline struct file
*io_file_get_fixed(struct io_ring_ctx
*ctx
,
6845 struct io_kiocb
*req
, int fd
)
6848 unsigned long file_ptr
;
6850 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6852 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6853 file_ptr
= io_fixed_file_slot(&ctx
->file_table
, fd
)->file_ptr
;
6854 file
= (struct file
*) (file_ptr
& FFS_MASK
);
6855 file_ptr
&= ~FFS_MASK
;
6856 /* mask in overlapping REQ_F and FFS bits */
6857 req
->flags
|= (file_ptr
<< REQ_F_NOWAIT_READ_BIT
);
6858 io_req_set_rsrc_node(req
);
6862 static struct file
*io_file_get_normal(struct io_ring_ctx
*ctx
,
6863 struct io_kiocb
*req
, int fd
)
6865 struct file
*file
= fget(fd
);
6867 trace_io_uring_file_get(ctx
, fd
);
6869 /* we don't allow fixed io_uring files */
6870 if (file
&& unlikely(file
->f_op
== &io_uring_fops
))
6871 io_req_track_inflight(req
);
6875 static inline struct file
*io_file_get(struct io_ring_ctx
*ctx
,
6876 struct io_kiocb
*req
, int fd
, bool fixed
)
6879 return io_file_get_fixed(ctx
, req
, fd
);
6881 return io_file_get_normal(ctx
, req
, fd
);
6884 static void io_req_task_link_timeout(struct io_kiocb
*req
, bool *locked
)
6886 struct io_kiocb
*prev
= req
->timeout
.prev
;
6890 ret
= io_try_cancel_userdata(req
, prev
->user_data
);
6891 io_req_complete_post(req
, ret
?: -ETIME
, 0);
6894 io_req_complete_post(req
, -ETIME
, 0);
6898 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6900 struct io_timeout_data
*data
= container_of(timer
,
6901 struct io_timeout_data
, timer
);
6902 struct io_kiocb
*prev
, *req
= data
->req
;
6903 struct io_ring_ctx
*ctx
= req
->ctx
;
6904 unsigned long flags
;
6906 spin_lock_irqsave(&ctx
->timeout_lock
, flags
);
6907 prev
= req
->timeout
.head
;
6908 req
->timeout
.head
= NULL
;
6911 * We don't expect the list to be empty, that will only happen if we
6912 * race with the completion of the linked work.
6915 io_remove_next_linked(prev
);
6916 if (!req_ref_inc_not_zero(prev
))
6919 list_del(&req
->timeout
.list
);
6920 req
->timeout
.prev
= prev
;
6921 spin_unlock_irqrestore(&ctx
->timeout_lock
, flags
);
6923 req
->io_task_work
.func
= io_req_task_link_timeout
;
6924 io_req_task_work_add(req
);
6925 return HRTIMER_NORESTART
;
6928 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6930 struct io_ring_ctx
*ctx
= req
->ctx
;
6932 spin_lock_irq(&ctx
->timeout_lock
);
6934 * If the back reference is NULL, then our linked request finished
6935 * before we got a chance to setup the timer
6937 if (req
->timeout
.head
) {
6938 struct io_timeout_data
*data
= req
->async_data
;
6940 data
->timer
.function
= io_link_timeout_fn
;
6941 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6943 list_add_tail(&req
->timeout
.list
, &ctx
->ltimeout_list
);
6945 spin_unlock_irq(&ctx
->timeout_lock
);
6946 /* drop submission reference */
6950 static void __io_queue_sqe(struct io_kiocb
*req
)
6951 __must_hold(&req
->ctx
->uring_lock
)
6953 struct io_kiocb
*linked_timeout
;
6957 ret
= io_issue_sqe(req
, IO_URING_F_NONBLOCK
|IO_URING_F_COMPLETE_DEFER
);
6960 * We async punt it if the file wasn't marked NOWAIT, or if the file
6961 * doesn't support non-blocking read/write attempts
6964 if (req
->flags
& REQ_F_COMPLETE_INLINE
) {
6965 struct io_ring_ctx
*ctx
= req
->ctx
;
6966 struct io_submit_state
*state
= &ctx
->submit_state
;
6968 state
->compl_reqs
[state
->compl_nr
++] = req
;
6969 if (state
->compl_nr
== ARRAY_SIZE(state
->compl_reqs
))
6970 io_submit_flush_completions(ctx
);
6974 linked_timeout
= io_prep_linked_timeout(req
);
6976 io_queue_linked_timeout(linked_timeout
);
6977 } else if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6978 linked_timeout
= io_prep_linked_timeout(req
);
6980 switch (io_arm_poll_handler(req
)) {
6981 case IO_APOLL_READY
:
6983 io_queue_linked_timeout(linked_timeout
);
6985 case IO_APOLL_ABORTED
:
6987 * Queued up for async execution, worker will release
6988 * submit reference when the iocb is actually submitted.
6990 io_queue_async_work(req
, NULL
);
6995 io_queue_linked_timeout(linked_timeout
);
6997 io_req_complete_failed(req
, ret
);
7001 static inline void io_queue_sqe(struct io_kiocb
*req
)
7002 __must_hold(&req
->ctx
->uring_lock
)
7004 if (unlikely(req
->ctx
->drain_active
) && io_drain_req(req
))
7007 if (likely(!(req
->flags
& (REQ_F_FORCE_ASYNC
| REQ_F_FAIL
)))) {
7008 __io_queue_sqe(req
);
7009 } else if (req
->flags
& REQ_F_FAIL
) {
7010 io_req_complete_fail_submit(req
);
7012 int ret
= io_req_prep_async(req
);
7015 io_req_complete_failed(req
, ret
);
7017 io_queue_async_work(req
, NULL
);
7022 * Check SQE restrictions (opcode and flags).
7024 * Returns 'true' if SQE is allowed, 'false' otherwise.
7026 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
7027 struct io_kiocb
*req
,
7028 unsigned int sqe_flags
)
7030 if (likely(!ctx
->restricted
))
7033 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
7036 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
7037 ctx
->restrictions
.sqe_flags_required
)
7040 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
7041 ctx
->restrictions
.sqe_flags_required
))
7047 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
7048 const struct io_uring_sqe
*sqe
)
7049 __must_hold(&ctx
->uring_lock
)
7051 struct io_submit_state
*state
;
7052 unsigned int sqe_flags
;
7053 int personality
, ret
= 0;
7055 /* req is partially pre-initialised, see io_preinit_req() */
7056 req
->opcode
= READ_ONCE(sqe
->opcode
);
7057 /* same numerical values with corresponding REQ_F_*, safe to copy */
7058 req
->flags
= sqe_flags
= READ_ONCE(sqe
->flags
);
7059 req
->user_data
= READ_ONCE(sqe
->user_data
);
7061 req
->fixed_rsrc_refs
= NULL
;
7062 req
->task
= current
;
7064 /* enforce forwards compatibility on users */
7065 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
7067 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
7069 if (!io_check_restriction(ctx
, req
, sqe_flags
))
7072 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
7073 !io_op_defs
[req
->opcode
].buffer_select
)
7075 if (unlikely(sqe_flags
& IOSQE_IO_DRAIN
))
7076 ctx
->drain_active
= true;
7078 personality
= READ_ONCE(sqe
->personality
);
7080 req
->creds
= xa_load(&ctx
->personalities
, personality
);
7083 get_cred(req
->creds
);
7084 req
->flags
|= REQ_F_CREDS
;
7086 state
= &ctx
->submit_state
;
7089 * Plug now if we have more than 1 IO left after this, and the target
7090 * is potentially a read/write to block based storage.
7092 if (!state
->plug_started
&& state
->ios_left
> 1 &&
7093 io_op_defs
[req
->opcode
].plug
) {
7094 blk_start_plug(&state
->plug
);
7095 state
->plug_started
= true;
7098 if (io_op_defs
[req
->opcode
].needs_file
) {
7099 req
->file
= io_file_get(ctx
, req
, READ_ONCE(sqe
->fd
),
7100 (sqe_flags
& IOSQE_FIXED_FILE
));
7101 if (unlikely(!req
->file
))
7109 static int io_submit_sqe(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
7110 const struct io_uring_sqe
*sqe
)
7111 __must_hold(&ctx
->uring_lock
)
7113 struct io_submit_link
*link
= &ctx
->submit_state
.link
;
7116 ret
= io_init_req(ctx
, req
, sqe
);
7117 if (unlikely(ret
)) {
7119 /* fail even hard links since we don't submit */
7122 * we can judge a link req is failed or cancelled by if
7123 * REQ_F_FAIL is set, but the head is an exception since
7124 * it may be set REQ_F_FAIL because of other req's failure
7125 * so let's leverage req->result to distinguish if a head
7126 * is set REQ_F_FAIL because of its failure or other req's
7127 * failure so that we can set the correct ret code for it.
7128 * init result here to avoid affecting the normal path.
7130 if (!(link
->head
->flags
& REQ_F_FAIL
))
7131 req_fail_link_node(link
->head
, -ECANCELED
);
7132 } else if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
7134 * the current req is a normal req, we should return
7135 * error and thus break the submittion loop.
7137 io_req_complete_failed(req
, ret
);
7140 req_fail_link_node(req
, ret
);
7142 ret
= io_req_prep(req
, sqe
);
7147 /* don't need @sqe from now on */
7148 trace_io_uring_submit_sqe(ctx
, req
, req
->opcode
, req
->user_data
,
7150 ctx
->flags
& IORING_SETUP_SQPOLL
);
7153 * If we already have a head request, queue this one for async
7154 * submittal once the head completes. If we don't have a head but
7155 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
7156 * submitted sync once the chain is complete. If none of those
7157 * conditions are true (normal request), then just queue it.
7160 struct io_kiocb
*head
= link
->head
;
7162 if (!(req
->flags
& REQ_F_FAIL
)) {
7163 ret
= io_req_prep_async(req
);
7164 if (unlikely(ret
)) {
7165 req_fail_link_node(req
, ret
);
7166 if (!(head
->flags
& REQ_F_FAIL
))
7167 req_fail_link_node(head
, -ECANCELED
);
7170 trace_io_uring_link(ctx
, req
, head
);
7171 link
->last
->link
= req
;
7174 /* last request of a link, enqueue the link */
7175 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
7180 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
7192 * Batched submission is done, ensure local IO is flushed out.
7194 static void io_submit_state_end(struct io_submit_state
*state
,
7195 struct io_ring_ctx
*ctx
)
7197 if (state
->link
.head
)
7198 io_queue_sqe(state
->link
.head
);
7199 if (state
->compl_nr
)
7200 io_submit_flush_completions(ctx
);
7201 if (state
->plug_started
)
7202 blk_finish_plug(&state
->plug
);
7206 * Start submission side cache.
7208 static void io_submit_state_start(struct io_submit_state
*state
,
7209 unsigned int max_ios
)
7211 state
->plug_started
= false;
7212 state
->ios_left
= max_ios
;
7213 /* set only head, no need to init link_last in advance */
7214 state
->link
.head
= NULL
;
7217 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
7219 struct io_rings
*rings
= ctx
->rings
;
7222 * Ensure any loads from the SQEs are done at this point,
7223 * since once we write the new head, the application could
7224 * write new data to them.
7226 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
7230 * Fetch an sqe, if one is available. Note this returns a pointer to memory
7231 * that is mapped by userspace. This means that care needs to be taken to
7232 * ensure that reads are stable, as we cannot rely on userspace always
7233 * being a good citizen. If members of the sqe are validated and then later
7234 * used, it's important that those reads are done through READ_ONCE() to
7235 * prevent a re-load down the line.
7237 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
7239 unsigned head
, mask
= ctx
->sq_entries
- 1;
7240 unsigned sq_idx
= ctx
->cached_sq_head
++ & mask
;
7243 * The cached sq head (or cq tail) serves two purposes:
7245 * 1) allows us to batch the cost of updating the user visible
7247 * 2) allows the kernel side to track the head on its own, even
7248 * though the application is the one updating it.
7250 head
= READ_ONCE(ctx
->sq_array
[sq_idx
]);
7251 if (likely(head
< ctx
->sq_entries
))
7252 return &ctx
->sq_sqes
[head
];
7254 /* drop invalid entries */
7256 WRITE_ONCE(ctx
->rings
->sq_dropped
,
7257 READ_ONCE(ctx
->rings
->sq_dropped
) + 1);
7261 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
7262 __must_hold(&ctx
->uring_lock
)
7266 /* make sure SQ entry isn't read before tail */
7267 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
7268 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
7270 io_get_task_refs(nr
);
7272 io_submit_state_start(&ctx
->submit_state
, nr
);
7273 while (submitted
< nr
) {
7274 const struct io_uring_sqe
*sqe
;
7275 struct io_kiocb
*req
;
7277 req
= io_alloc_req(ctx
);
7278 if (unlikely(!req
)) {
7280 submitted
= -EAGAIN
;
7283 sqe
= io_get_sqe(ctx
);
7284 if (unlikely(!sqe
)) {
7285 list_add(&req
->inflight_entry
, &ctx
->submit_state
.free_list
);
7288 /* will complete beyond this point, count as submitted */
7290 if (io_submit_sqe(ctx
, req
, sqe
))
7294 if (unlikely(submitted
!= nr
)) {
7295 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
7296 int unused
= nr
- ref_used
;
7298 current
->io_uring
->cached_refs
+= unused
;
7299 percpu_ref_put_many(&ctx
->refs
, unused
);
7302 io_submit_state_end(&ctx
->submit_state
, ctx
);
7303 /* Commit SQ ring head once we've consumed and submitted all SQEs */
7304 io_commit_sqring(ctx
);
7309 static inline bool io_sqd_events_pending(struct io_sq_data
*sqd
)
7311 return READ_ONCE(sqd
->state
);
7314 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
7316 /* Tell userspace we may need a wakeup call */
7317 spin_lock(&ctx
->completion_lock
);
7318 WRITE_ONCE(ctx
->rings
->sq_flags
,
7319 ctx
->rings
->sq_flags
| IORING_SQ_NEED_WAKEUP
);
7320 spin_unlock(&ctx
->completion_lock
);
7323 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
7325 spin_lock(&ctx
->completion_lock
);
7326 WRITE_ONCE(ctx
->rings
->sq_flags
,
7327 ctx
->rings
->sq_flags
& ~IORING_SQ_NEED_WAKEUP
);
7328 spin_unlock(&ctx
->completion_lock
);
7331 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
7333 unsigned int to_submit
;
7336 to_submit
= io_sqring_entries(ctx
);
7337 /* if we're handling multiple rings, cap submit size for fairness */
7338 if (cap_entries
&& to_submit
> IORING_SQPOLL_CAP_ENTRIES_VALUE
)
7339 to_submit
= IORING_SQPOLL_CAP_ENTRIES_VALUE
;
7341 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
7342 unsigned nr_events
= 0;
7343 const struct cred
*creds
= NULL
;
7345 if (ctx
->sq_creds
!= current_cred())
7346 creds
= override_creds(ctx
->sq_creds
);
7348 mutex_lock(&ctx
->uring_lock
);
7349 if (!list_empty(&ctx
->iopoll_list
))
7350 io_do_iopoll(ctx
, &nr_events
, 0);
7353 * Don't submit if refs are dying, good for io_uring_register(),
7354 * but also it is relied upon by io_ring_exit_work()
7356 if (to_submit
&& likely(!percpu_ref_is_dying(&ctx
->refs
)) &&
7357 !(ctx
->flags
& IORING_SETUP_R_DISABLED
))
7358 ret
= io_submit_sqes(ctx
, to_submit
);
7359 mutex_unlock(&ctx
->uring_lock
);
7361 if (to_submit
&& wq_has_sleeper(&ctx
->sqo_sq_wait
))
7362 wake_up(&ctx
->sqo_sq_wait
);
7364 revert_creds(creds
);
7370 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
7372 struct io_ring_ctx
*ctx
;
7373 unsigned sq_thread_idle
= 0;
7375 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7376 sq_thread_idle
= max(sq_thread_idle
, ctx
->sq_thread_idle
);
7377 sqd
->sq_thread_idle
= sq_thread_idle
;
7380 static bool io_sqd_handle_event(struct io_sq_data
*sqd
)
7382 bool did_sig
= false;
7383 struct ksignal ksig
;
7385 if (test_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
) ||
7386 signal_pending(current
)) {
7387 mutex_unlock(&sqd
->lock
);
7388 if (signal_pending(current
))
7389 did_sig
= get_signal(&ksig
);
7391 mutex_lock(&sqd
->lock
);
7393 return did_sig
|| test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
);
7396 static int io_sq_thread(void *data
)
7398 struct io_sq_data
*sqd
= data
;
7399 struct io_ring_ctx
*ctx
;
7400 unsigned long timeout
= 0;
7401 char buf
[TASK_COMM_LEN
];
7404 snprintf(buf
, sizeof(buf
), "iou-sqp-%d", sqd
->task_pid
);
7405 set_task_comm(current
, buf
);
7407 if (sqd
->sq_cpu
!= -1)
7408 set_cpus_allowed_ptr(current
, cpumask_of(sqd
->sq_cpu
));
7410 set_cpus_allowed_ptr(current
, cpu_online_mask
);
7411 current
->flags
|= PF_NO_SETAFFINITY
;
7413 mutex_lock(&sqd
->lock
);
7415 bool cap_entries
, sqt_spin
= false;
7417 if (io_sqd_events_pending(sqd
) || signal_pending(current
)) {
7418 if (io_sqd_handle_event(sqd
))
7420 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7423 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
7424 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7425 int ret
= __io_sq_thread(ctx
, cap_entries
);
7427 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
7430 if (io_run_task_work())
7433 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
7436 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7440 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
7441 if (!io_sqd_events_pending(sqd
) && !current
->task_works
) {
7442 bool needs_sched
= true;
7444 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7445 io_ring_set_wakeup_flag(ctx
);
7447 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
7448 !list_empty_careful(&ctx
->iopoll_list
)) {
7449 needs_sched
= false;
7452 if (io_sqring_entries(ctx
)) {
7453 needs_sched
= false;
7459 mutex_unlock(&sqd
->lock
);
7461 mutex_lock(&sqd
->lock
);
7463 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7464 io_ring_clear_wakeup_flag(ctx
);
7467 finish_wait(&sqd
->wait
, &wait
);
7468 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7471 io_uring_cancel_generic(true, sqd
);
7473 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7474 io_ring_set_wakeup_flag(ctx
);
7476 mutex_unlock(&sqd
->lock
);
7478 complete(&sqd
->exited
);
7482 struct io_wait_queue
{
7483 struct wait_queue_entry wq
;
7484 struct io_ring_ctx
*ctx
;
7486 unsigned nr_timeouts
;
7489 static inline bool io_should_wake(struct io_wait_queue
*iowq
)
7491 struct io_ring_ctx
*ctx
= iowq
->ctx
;
7492 int dist
= ctx
->cached_cq_tail
- (int) iowq
->cq_tail
;
7495 * Wake up if we have enough events, or if a timeout occurred since we
7496 * started waiting. For timeouts, we always want to return to userspace,
7497 * regardless of event count.
7499 return dist
>= 0 || atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
7502 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
7503 int wake_flags
, void *key
)
7505 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
7509 * Cannot safely flush overflowed CQEs from here, ensure we wake up
7510 * the task, and the next invocation will do it.
7512 if (io_should_wake(iowq
) || test_bit(0, &iowq
->ctx
->check_cq_overflow
))
7513 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
7517 static int io_run_task_work_sig(void)
7519 if (io_run_task_work())
7521 if (!signal_pending(current
))
7523 if (test_thread_flag(TIF_NOTIFY_SIGNAL
))
7524 return -ERESTARTSYS
;
7528 /* when returns >0, the caller should retry */
7529 static inline int io_cqring_wait_schedule(struct io_ring_ctx
*ctx
,
7530 struct io_wait_queue
*iowq
,
7531 signed long *timeout
)
7535 /* make sure we run task_work before checking for signals */
7536 ret
= io_run_task_work_sig();
7537 if (ret
|| io_should_wake(iowq
))
7539 /* let the caller flush overflows, retry */
7540 if (test_bit(0, &ctx
->check_cq_overflow
))
7543 *timeout
= schedule_timeout(*timeout
);
7544 return !*timeout
? -ETIME
: 1;
7548 * Wait until events become available, if we don't already have some. The
7549 * application must reap them itself, as they reside on the shared cq ring.
7551 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
7552 const sigset_t __user
*sig
, size_t sigsz
,
7553 struct __kernel_timespec __user
*uts
)
7555 struct io_wait_queue iowq
;
7556 struct io_rings
*rings
= ctx
->rings
;
7557 signed long timeout
= MAX_SCHEDULE_TIMEOUT
;
7561 io_cqring_overflow_flush(ctx
);
7562 if (io_cqring_events(ctx
) >= min_events
)
7564 if (!io_run_task_work())
7569 struct timespec64 ts
;
7571 if (get_timespec64(&ts
, uts
))
7573 timeout
= timespec64_to_jiffies(&ts
);
7577 #ifdef CONFIG_COMPAT
7578 if (in_compat_syscall())
7579 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
7583 ret
= set_user_sigmask(sig
, sigsz
);
7589 init_waitqueue_func_entry(&iowq
.wq
, io_wake_function
);
7590 iowq
.wq
.private = current
;
7591 INIT_LIST_HEAD(&iowq
.wq
.entry
);
7593 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
7594 iowq
.cq_tail
= READ_ONCE(ctx
->rings
->cq
.head
) + min_events
;
7596 trace_io_uring_cqring_wait(ctx
, min_events
);
7598 /* if we can't even flush overflow, don't wait for more */
7599 if (!io_cqring_overflow_flush(ctx
)) {
7603 prepare_to_wait_exclusive(&ctx
->cq_wait
, &iowq
.wq
,
7604 TASK_INTERRUPTIBLE
);
7605 ret
= io_cqring_wait_schedule(ctx
, &iowq
, &timeout
);
7606 finish_wait(&ctx
->cq_wait
, &iowq
.wq
);
7610 restore_saved_sigmask_unless(ret
== -EINTR
);
7612 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7615 static void io_free_page_table(void **table
, size_t size
)
7617 unsigned i
, nr_tables
= DIV_ROUND_UP(size
, PAGE_SIZE
);
7619 for (i
= 0; i
< nr_tables
; i
++)
7624 static void **io_alloc_page_table(size_t size
)
7626 unsigned i
, nr_tables
= DIV_ROUND_UP(size
, PAGE_SIZE
);
7627 size_t init_size
= size
;
7630 table
= kcalloc(nr_tables
, sizeof(*table
), GFP_KERNEL_ACCOUNT
);
7634 for (i
= 0; i
< nr_tables
; i
++) {
7635 unsigned int this_size
= min_t(size_t, size
, PAGE_SIZE
);
7637 table
[i
] = kzalloc(this_size
, GFP_KERNEL_ACCOUNT
);
7639 io_free_page_table(table
, init_size
);
7647 static void io_rsrc_node_destroy(struct io_rsrc_node
*ref_node
)
7649 percpu_ref_exit(&ref_node
->refs
);
7653 static void io_rsrc_node_ref_zero(struct percpu_ref
*ref
)
7655 struct io_rsrc_node
*node
= container_of(ref
, struct io_rsrc_node
, refs
);
7656 struct io_ring_ctx
*ctx
= node
->rsrc_data
->ctx
;
7657 unsigned long flags
;
7658 bool first_add
= false;
7660 spin_lock_irqsave(&ctx
->rsrc_ref_lock
, flags
);
7663 while (!list_empty(&ctx
->rsrc_ref_list
)) {
7664 node
= list_first_entry(&ctx
->rsrc_ref_list
,
7665 struct io_rsrc_node
, node
);
7666 /* recycle ref nodes in order */
7669 list_del(&node
->node
);
7670 first_add
|= llist_add(&node
->llist
, &ctx
->rsrc_put_llist
);
7672 spin_unlock_irqrestore(&ctx
->rsrc_ref_lock
, flags
);
7675 mod_delayed_work(system_wq
, &ctx
->rsrc_put_work
, HZ
);
7678 static struct io_rsrc_node
*io_rsrc_node_alloc(struct io_ring_ctx
*ctx
)
7680 struct io_rsrc_node
*ref_node
;
7682 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7686 if (percpu_ref_init(&ref_node
->refs
, io_rsrc_node_ref_zero
,
7691 INIT_LIST_HEAD(&ref_node
->node
);
7692 INIT_LIST_HEAD(&ref_node
->rsrc_list
);
7693 ref_node
->done
= false;
7697 static void io_rsrc_node_switch(struct io_ring_ctx
*ctx
,
7698 struct io_rsrc_data
*data_to_kill
)
7700 WARN_ON_ONCE(!ctx
->rsrc_backup_node
);
7701 WARN_ON_ONCE(data_to_kill
&& !ctx
->rsrc_node
);
7704 struct io_rsrc_node
*rsrc_node
= ctx
->rsrc_node
;
7706 rsrc_node
->rsrc_data
= data_to_kill
;
7707 spin_lock_irq(&ctx
->rsrc_ref_lock
);
7708 list_add_tail(&rsrc_node
->node
, &ctx
->rsrc_ref_list
);
7709 spin_unlock_irq(&ctx
->rsrc_ref_lock
);
7711 atomic_inc(&data_to_kill
->refs
);
7712 percpu_ref_kill(&rsrc_node
->refs
);
7713 ctx
->rsrc_node
= NULL
;
7716 if (!ctx
->rsrc_node
) {
7717 ctx
->rsrc_node
= ctx
->rsrc_backup_node
;
7718 ctx
->rsrc_backup_node
= NULL
;
7722 static int io_rsrc_node_switch_start(struct io_ring_ctx
*ctx
)
7724 if (ctx
->rsrc_backup_node
)
7726 ctx
->rsrc_backup_node
= io_rsrc_node_alloc(ctx
);
7727 return ctx
->rsrc_backup_node
? 0 : -ENOMEM
;
7730 static int io_rsrc_ref_quiesce(struct io_rsrc_data
*data
, struct io_ring_ctx
*ctx
)
7734 /* As we may drop ->uring_lock, other task may have started quiesce */
7738 data
->quiesce
= true;
7740 ret
= io_rsrc_node_switch_start(ctx
);
7743 io_rsrc_node_switch(ctx
, data
);
7745 /* kill initial ref, already quiesced if zero */
7746 if (atomic_dec_and_test(&data
->refs
))
7748 mutex_unlock(&ctx
->uring_lock
);
7749 flush_delayed_work(&ctx
->rsrc_put_work
);
7750 ret
= wait_for_completion_interruptible(&data
->done
);
7752 mutex_lock(&ctx
->uring_lock
);
7756 atomic_inc(&data
->refs
);
7757 /* wait for all works potentially completing data->done */
7758 flush_delayed_work(&ctx
->rsrc_put_work
);
7759 reinit_completion(&data
->done
);
7761 ret
= io_run_task_work_sig();
7762 mutex_lock(&ctx
->uring_lock
);
7764 data
->quiesce
= false;
7769 static u64
*io_get_tag_slot(struct io_rsrc_data
*data
, unsigned int idx
)
7771 unsigned int off
= idx
& IO_RSRC_TAG_TABLE_MASK
;
7772 unsigned int table_idx
= idx
>> IO_RSRC_TAG_TABLE_SHIFT
;
7774 return &data
->tags
[table_idx
][off
];
7777 static void io_rsrc_data_free(struct io_rsrc_data
*data
)
7779 size_t size
= data
->nr
* sizeof(data
->tags
[0][0]);
7782 io_free_page_table((void **)data
->tags
, size
);
7786 static int io_rsrc_data_alloc(struct io_ring_ctx
*ctx
, rsrc_put_fn
*do_put
,
7787 u64 __user
*utags
, unsigned nr
,
7788 struct io_rsrc_data
**pdata
)
7790 struct io_rsrc_data
*data
;
7794 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
7797 data
->tags
= (u64
**)io_alloc_page_table(nr
* sizeof(data
->tags
[0][0]));
7805 data
->do_put
= do_put
;
7808 for (i
= 0; i
< nr
; i
++) {
7809 u64
*tag_slot
= io_get_tag_slot(data
, i
);
7811 if (copy_from_user(tag_slot
, &utags
[i
],
7817 atomic_set(&data
->refs
, 1);
7818 init_completion(&data
->done
);
7822 io_rsrc_data_free(data
);
7826 static bool io_alloc_file_tables(struct io_file_table
*table
, unsigned nr_files
)
7828 table
->files
= kvcalloc(nr_files
, sizeof(table
->files
[0]),
7829 GFP_KERNEL_ACCOUNT
);
7830 return !!table
->files
;
7833 static void io_free_file_tables(struct io_file_table
*table
)
7835 kvfree(table
->files
);
7836 table
->files
= NULL
;
7839 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7841 #if defined(CONFIG_UNIX)
7842 if (ctx
->ring_sock
) {
7843 struct sock
*sock
= ctx
->ring_sock
->sk
;
7844 struct sk_buff
*skb
;
7846 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7852 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7855 file
= io_file_from_index(ctx
, i
);
7860 io_free_file_tables(&ctx
->file_table
);
7861 io_rsrc_data_free(ctx
->file_data
);
7862 ctx
->file_data
= NULL
;
7863 ctx
->nr_user_files
= 0;
7866 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7870 if (!ctx
->file_data
)
7872 ret
= io_rsrc_ref_quiesce(ctx
->file_data
, ctx
);
7874 __io_sqe_files_unregister(ctx
);
7878 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7879 __releases(&sqd
->lock
)
7881 WARN_ON_ONCE(sqd
->thread
== current
);
7884 * Do the dance but not conditional clear_bit() because it'd race with
7885 * other threads incrementing park_pending and setting the bit.
7887 clear_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7888 if (atomic_dec_return(&sqd
->park_pending
))
7889 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7890 mutex_unlock(&sqd
->lock
);
7893 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7894 __acquires(&sqd
->lock
)
7896 WARN_ON_ONCE(sqd
->thread
== current
);
7898 atomic_inc(&sqd
->park_pending
);
7899 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7900 mutex_lock(&sqd
->lock
);
7902 wake_up_process(sqd
->thread
);
7905 static void io_sq_thread_stop(struct io_sq_data
*sqd
)
7907 WARN_ON_ONCE(sqd
->thread
== current
);
7908 WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
));
7910 set_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
);
7911 mutex_lock(&sqd
->lock
);
7913 wake_up_process(sqd
->thread
);
7914 mutex_unlock(&sqd
->lock
);
7915 wait_for_completion(&sqd
->exited
);
7918 static void io_put_sq_data(struct io_sq_data
*sqd
)
7920 if (refcount_dec_and_test(&sqd
->refs
)) {
7921 WARN_ON_ONCE(atomic_read(&sqd
->park_pending
));
7923 io_sq_thread_stop(sqd
);
7928 static void io_sq_thread_finish(struct io_ring_ctx
*ctx
)
7930 struct io_sq_data
*sqd
= ctx
->sq_data
;
7933 io_sq_thread_park(sqd
);
7934 list_del_init(&ctx
->sqd_list
);
7935 io_sqd_update_thread_idle(sqd
);
7936 io_sq_thread_unpark(sqd
);
7938 io_put_sq_data(sqd
);
7939 ctx
->sq_data
= NULL
;
7943 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7945 struct io_ring_ctx
*ctx_attach
;
7946 struct io_sq_data
*sqd
;
7949 f
= fdget(p
->wq_fd
);
7951 return ERR_PTR(-ENXIO
);
7952 if (f
.file
->f_op
!= &io_uring_fops
) {
7954 return ERR_PTR(-EINVAL
);
7957 ctx_attach
= f
.file
->private_data
;
7958 sqd
= ctx_attach
->sq_data
;
7961 return ERR_PTR(-EINVAL
);
7963 if (sqd
->task_tgid
!= current
->tgid
) {
7965 return ERR_PTR(-EPERM
);
7968 refcount_inc(&sqd
->refs
);
7973 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
,
7976 struct io_sq_data
*sqd
;
7979 if (p
->flags
& IORING_SETUP_ATTACH_WQ
) {
7980 sqd
= io_attach_sq_data(p
);
7985 /* fall through for EPERM case, setup new sqd/task */
7986 if (PTR_ERR(sqd
) != -EPERM
)
7990 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7992 return ERR_PTR(-ENOMEM
);
7994 atomic_set(&sqd
->park_pending
, 0);
7995 refcount_set(&sqd
->refs
, 1);
7996 INIT_LIST_HEAD(&sqd
->ctx_list
);
7997 mutex_init(&sqd
->lock
);
7998 init_waitqueue_head(&sqd
->wait
);
7999 init_completion(&sqd
->exited
);
8003 #if defined(CONFIG_UNIX)
8005 * Ensure the UNIX gc is aware of our file set, so we are certain that
8006 * the io_uring can be safely unregistered on process exit, even if we have
8007 * loops in the file referencing.
8009 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
8011 struct sock
*sk
= ctx
->ring_sock
->sk
;
8012 struct scm_fp_list
*fpl
;
8013 struct sk_buff
*skb
;
8016 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
8020 skb
= alloc_skb(0, GFP_KERNEL
);
8029 fpl
->user
= get_uid(current_user());
8030 for (i
= 0; i
< nr
; i
++) {
8031 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
8035 fpl
->fp
[nr_files
] = get_file(file
);
8036 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
8041 fpl
->max
= SCM_MAX_FD
;
8042 fpl
->count
= nr_files
;
8043 UNIXCB(skb
).fp
= fpl
;
8044 skb
->destructor
= unix_destruct_scm
;
8045 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
8046 skb_queue_head(&sk
->sk_receive_queue
, skb
);
8048 for (i
= 0; i
< nr_files
; i
++)
8059 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
8060 * causes regular reference counting to break down. We rely on the UNIX
8061 * garbage collection to take care of this problem for us.
8063 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
8065 unsigned left
, total
;
8069 left
= ctx
->nr_user_files
;
8071 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
8073 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
8077 total
+= this_files
;
8083 while (total
< ctx
->nr_user_files
) {
8084 struct file
*file
= io_file_from_index(ctx
, total
);
8094 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
8100 static void io_rsrc_file_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
8102 struct file
*file
= prsrc
->file
;
8103 #if defined(CONFIG_UNIX)
8104 struct sock
*sock
= ctx
->ring_sock
->sk
;
8105 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
8106 struct sk_buff
*skb
;
8109 __skb_queue_head_init(&list
);
8112 * Find the skb that holds this file in its SCM_RIGHTS. When found,
8113 * remove this entry and rearrange the file array.
8115 skb
= skb_dequeue(head
);
8117 struct scm_fp_list
*fp
;
8119 fp
= UNIXCB(skb
).fp
;
8120 for (i
= 0; i
< fp
->count
; i
++) {
8123 if (fp
->fp
[i
] != file
)
8126 unix_notinflight(fp
->user
, fp
->fp
[i
]);
8127 left
= fp
->count
- 1 - i
;
8129 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
8130 left
* sizeof(struct file
*));
8137 __skb_queue_tail(&list
, skb
);
8147 __skb_queue_tail(&list
, skb
);
8149 skb
= skb_dequeue(head
);
8152 if (skb_peek(&list
)) {
8153 spin_lock_irq(&head
->lock
);
8154 while ((skb
= __skb_dequeue(&list
)) != NULL
)
8155 __skb_queue_tail(head
, skb
);
8156 spin_unlock_irq(&head
->lock
);
8163 static void __io_rsrc_put_work(struct io_rsrc_node
*ref_node
)
8165 struct io_rsrc_data
*rsrc_data
= ref_node
->rsrc_data
;
8166 struct io_ring_ctx
*ctx
= rsrc_data
->ctx
;
8167 struct io_rsrc_put
*prsrc
, *tmp
;
8169 list_for_each_entry_safe(prsrc
, tmp
, &ref_node
->rsrc_list
, list
) {
8170 list_del(&prsrc
->list
);
8173 bool lock_ring
= ctx
->flags
& IORING_SETUP_IOPOLL
;
8175 io_ring_submit_lock(ctx
, lock_ring
);
8176 spin_lock(&ctx
->completion_lock
);
8177 io_cqring_fill_event(ctx
, prsrc
->tag
, 0, 0);
8179 io_commit_cqring(ctx
);
8180 spin_unlock(&ctx
->completion_lock
);
8181 io_cqring_ev_posted(ctx
);
8182 io_ring_submit_unlock(ctx
, lock_ring
);
8185 rsrc_data
->do_put(ctx
, prsrc
);
8189 io_rsrc_node_destroy(ref_node
);
8190 if (atomic_dec_and_test(&rsrc_data
->refs
))
8191 complete(&rsrc_data
->done
);
8194 static void io_rsrc_put_work(struct work_struct
*work
)
8196 struct io_ring_ctx
*ctx
;
8197 struct llist_node
*node
;
8199 ctx
= container_of(work
, struct io_ring_ctx
, rsrc_put_work
.work
);
8200 node
= llist_del_all(&ctx
->rsrc_put_llist
);
8203 struct io_rsrc_node
*ref_node
;
8204 struct llist_node
*next
= node
->next
;
8206 ref_node
= llist_entry(node
, struct io_rsrc_node
, llist
);
8207 __io_rsrc_put_work(ref_node
);
8212 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8213 unsigned nr_args
, u64 __user
*tags
)
8215 __s32 __user
*fds
= (__s32 __user
*) arg
;
8224 if (nr_args
> IORING_MAX_FIXED_FILES
)
8226 if (nr_args
> rlimit(RLIMIT_NOFILE
))
8228 ret
= io_rsrc_node_switch_start(ctx
);
8231 ret
= io_rsrc_data_alloc(ctx
, io_rsrc_file_put
, tags
, nr_args
,
8237 if (!io_alloc_file_tables(&ctx
->file_table
, nr_args
))
8240 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
8241 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
8245 /* allow sparse sets */
8248 if (unlikely(*io_get_tag_slot(ctx
->file_data
, i
)))
8255 if (unlikely(!file
))
8259 * Don't allow io_uring instances to be registered. If UNIX
8260 * isn't enabled, then this causes a reference cycle and this
8261 * instance can never get freed. If UNIX is enabled we'll
8262 * handle it just fine, but there's still no point in allowing
8263 * a ring fd as it doesn't support regular read/write anyway.
8265 if (file
->f_op
== &io_uring_fops
) {
8269 io_fixed_file_set(io_fixed_file_slot(&ctx
->file_table
, i
), file
);
8272 ret
= io_sqe_files_scm(ctx
);
8274 __io_sqe_files_unregister(ctx
);
8278 io_rsrc_node_switch(ctx
, NULL
);
8281 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
8282 file
= io_file_from_index(ctx
, i
);
8286 io_free_file_tables(&ctx
->file_table
);
8287 ctx
->nr_user_files
= 0;
8289 io_rsrc_data_free(ctx
->file_data
);
8290 ctx
->file_data
= NULL
;
8294 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
8297 #if defined(CONFIG_UNIX)
8298 struct sock
*sock
= ctx
->ring_sock
->sk
;
8299 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
8300 struct sk_buff
*skb
;
8303 * See if we can merge this file into an existing skb SCM_RIGHTS
8304 * file set. If there's no room, fall back to allocating a new skb
8305 * and filling it in.
8307 spin_lock_irq(&head
->lock
);
8308 skb
= skb_peek(head
);
8310 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
8312 if (fpl
->count
< SCM_MAX_FD
) {
8313 __skb_unlink(skb
, head
);
8314 spin_unlock_irq(&head
->lock
);
8315 fpl
->fp
[fpl
->count
] = get_file(file
);
8316 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
8318 spin_lock_irq(&head
->lock
);
8319 __skb_queue_head(head
, skb
);
8324 spin_unlock_irq(&head
->lock
);
8331 return __io_sqe_files_scm(ctx
, 1, index
);
8337 static int io_queue_rsrc_removal(struct io_rsrc_data
*data
, unsigned idx
,
8338 struct io_rsrc_node
*node
, void *rsrc
)
8340 struct io_rsrc_put
*prsrc
;
8342 prsrc
= kzalloc(sizeof(*prsrc
), GFP_KERNEL
);
8346 prsrc
->tag
= *io_get_tag_slot(data
, idx
);
8348 list_add(&prsrc
->list
, &node
->rsrc_list
);
8352 static int io_install_fixed_file(struct io_kiocb
*req
, struct file
*file
,
8353 unsigned int issue_flags
, u32 slot_index
)
8355 struct io_ring_ctx
*ctx
= req
->ctx
;
8356 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
8357 bool needs_switch
= false;
8358 struct io_fixed_file
*file_slot
;
8361 io_ring_submit_lock(ctx
, !force_nonblock
);
8362 if (file
->f_op
== &io_uring_fops
)
8365 if (!ctx
->file_data
)
8368 if (slot_index
>= ctx
->nr_user_files
)
8371 slot_index
= array_index_nospec(slot_index
, ctx
->nr_user_files
);
8372 file_slot
= io_fixed_file_slot(&ctx
->file_table
, slot_index
);
8374 if (file_slot
->file_ptr
) {
8375 struct file
*old_file
;
8377 ret
= io_rsrc_node_switch_start(ctx
);
8381 old_file
= (struct file
*)(file_slot
->file_ptr
& FFS_MASK
);
8382 ret
= io_queue_rsrc_removal(ctx
->file_data
, slot_index
,
8383 ctx
->rsrc_node
, old_file
);
8386 file_slot
->file_ptr
= 0;
8387 needs_switch
= true;
8390 *io_get_tag_slot(ctx
->file_data
, slot_index
) = 0;
8391 io_fixed_file_set(file_slot
, file
);
8392 ret
= io_sqe_file_register(ctx
, file
, slot_index
);
8394 file_slot
->file_ptr
= 0;
8401 io_rsrc_node_switch(ctx
, ctx
->file_data
);
8402 io_ring_submit_unlock(ctx
, !force_nonblock
);
8408 static int io_close_fixed(struct io_kiocb
*req
, unsigned int issue_flags
)
8410 unsigned int offset
= req
->close
.file_slot
- 1;
8411 struct io_ring_ctx
*ctx
= req
->ctx
;
8412 struct io_fixed_file
*file_slot
;
8416 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
8418 if (unlikely(!ctx
->file_data
))
8421 if (offset
>= ctx
->nr_user_files
)
8423 ret
= io_rsrc_node_switch_start(ctx
);
8427 i
= array_index_nospec(offset
, ctx
->nr_user_files
);
8428 file_slot
= io_fixed_file_slot(&ctx
->file_table
, i
);
8430 if (!file_slot
->file_ptr
)
8433 file
= (struct file
*)(file_slot
->file_ptr
& FFS_MASK
);
8434 ret
= io_queue_rsrc_removal(ctx
->file_data
, offset
, ctx
->rsrc_node
, file
);
8438 file_slot
->file_ptr
= 0;
8439 io_rsrc_node_switch(ctx
, ctx
->file_data
);
8442 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
8446 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
8447 struct io_uring_rsrc_update2
*up
,
8450 u64 __user
*tags
= u64_to_user_ptr(up
->tags
);
8451 __s32 __user
*fds
= u64_to_user_ptr(up
->data
);
8452 struct io_rsrc_data
*data
= ctx
->file_data
;
8453 struct io_fixed_file
*file_slot
;
8457 bool needs_switch
= false;
8459 if (!ctx
->file_data
)
8461 if (up
->offset
+ nr_args
> ctx
->nr_user_files
)
8464 for (done
= 0; done
< nr_args
; done
++) {
8467 if ((tags
&& copy_from_user(&tag
, &tags
[done
], sizeof(tag
))) ||
8468 copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
8472 if ((fd
== IORING_REGISTER_FILES_SKIP
|| fd
== -1) && tag
) {
8476 if (fd
== IORING_REGISTER_FILES_SKIP
)
8479 i
= array_index_nospec(up
->offset
+ done
, ctx
->nr_user_files
);
8480 file_slot
= io_fixed_file_slot(&ctx
->file_table
, i
);
8482 if (file_slot
->file_ptr
) {
8483 file
= (struct file
*)(file_slot
->file_ptr
& FFS_MASK
);
8484 err
= io_queue_rsrc_removal(data
, up
->offset
+ done
,
8485 ctx
->rsrc_node
, file
);
8488 file_slot
->file_ptr
= 0;
8489 needs_switch
= true;
8498 * Don't allow io_uring instances to be registered. If
8499 * UNIX isn't enabled, then this causes a reference
8500 * cycle and this instance can never get freed. If UNIX
8501 * is enabled we'll handle it just fine, but there's
8502 * still no point in allowing a ring fd as it doesn't
8503 * support regular read/write anyway.
8505 if (file
->f_op
== &io_uring_fops
) {
8510 *io_get_tag_slot(data
, up
->offset
+ done
) = tag
;
8511 io_fixed_file_set(file_slot
, file
);
8512 err
= io_sqe_file_register(ctx
, file
, i
);
8514 file_slot
->file_ptr
= 0;
8522 io_rsrc_node_switch(ctx
, data
);
8523 return done
? done
: err
;
8526 static struct io_wq
*io_init_wq_offload(struct io_ring_ctx
*ctx
,
8527 struct task_struct
*task
)
8529 struct io_wq_hash
*hash
;
8530 struct io_wq_data data
;
8531 unsigned int concurrency
;
8533 mutex_lock(&ctx
->uring_lock
);
8534 hash
= ctx
->hash_map
;
8536 hash
= kzalloc(sizeof(*hash
), GFP_KERNEL
);
8538 mutex_unlock(&ctx
->uring_lock
);
8539 return ERR_PTR(-ENOMEM
);
8541 refcount_set(&hash
->refs
, 1);
8542 init_waitqueue_head(&hash
->wait
);
8543 ctx
->hash_map
= hash
;
8545 mutex_unlock(&ctx
->uring_lock
);
8549 data
.free_work
= io_wq_free_work
;
8550 data
.do_work
= io_wq_submit_work
;
8552 /* Do QD, or 4 * CPUS, whatever is smallest */
8553 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
8555 return io_wq_create(concurrency
, &data
);
8558 static int io_uring_alloc_task_context(struct task_struct
*task
,
8559 struct io_ring_ctx
*ctx
)
8561 struct io_uring_task
*tctx
;
8564 tctx
= kzalloc(sizeof(*tctx
), GFP_KERNEL
);
8565 if (unlikely(!tctx
))
8568 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
8569 if (unlikely(ret
)) {
8574 tctx
->io_wq
= io_init_wq_offload(ctx
, task
);
8575 if (IS_ERR(tctx
->io_wq
)) {
8576 ret
= PTR_ERR(tctx
->io_wq
);
8577 percpu_counter_destroy(&tctx
->inflight
);
8583 init_waitqueue_head(&tctx
->wait
);
8584 atomic_set(&tctx
->in_idle
, 0);
8585 atomic_set(&tctx
->inflight_tracked
, 0);
8586 task
->io_uring
= tctx
;
8587 spin_lock_init(&tctx
->task_lock
);
8588 INIT_WQ_LIST(&tctx
->task_list
);
8589 init_task_work(&tctx
->task_work
, tctx_task_work
);
8593 void __io_uring_free(struct task_struct
*tsk
)
8595 struct io_uring_task
*tctx
= tsk
->io_uring
;
8597 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
8598 WARN_ON_ONCE(tctx
->io_wq
);
8599 WARN_ON_ONCE(tctx
->cached_refs
);
8601 percpu_counter_destroy(&tctx
->inflight
);
8603 tsk
->io_uring
= NULL
;
8606 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
8607 struct io_uring_params
*p
)
8611 /* Retain compatibility with failing for an invalid attach attempt */
8612 if ((ctx
->flags
& (IORING_SETUP_ATTACH_WQ
| IORING_SETUP_SQPOLL
)) ==
8613 IORING_SETUP_ATTACH_WQ
) {
8616 f
= fdget(p
->wq_fd
);
8619 if (f
.file
->f_op
!= &io_uring_fops
) {
8625 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8626 struct task_struct
*tsk
;
8627 struct io_sq_data
*sqd
;
8630 sqd
= io_get_sq_data(p
, &attached
);
8636 ctx
->sq_creds
= get_current_cred();
8638 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
8639 if (!ctx
->sq_thread_idle
)
8640 ctx
->sq_thread_idle
= HZ
;
8642 io_sq_thread_park(sqd
);
8643 list_add(&ctx
->sqd_list
, &sqd
->ctx_list
);
8644 io_sqd_update_thread_idle(sqd
);
8645 /* don't attach to a dying SQPOLL thread, would be racy */
8646 ret
= (attached
&& !sqd
->thread
) ? -ENXIO
: 0;
8647 io_sq_thread_unpark(sqd
);
8654 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8655 int cpu
= p
->sq_thread_cpu
;
8658 if (cpu
>= nr_cpu_ids
|| !cpu_online(cpu
))
8665 sqd
->task_pid
= current
->pid
;
8666 sqd
->task_tgid
= current
->tgid
;
8667 tsk
= create_io_thread(io_sq_thread
, sqd
, NUMA_NO_NODE
);
8674 ret
= io_uring_alloc_task_context(tsk
, ctx
);
8675 wake_up_new_task(tsk
);
8678 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8679 /* Can't have SQ_AFF without SQPOLL */
8686 complete(&ctx
->sq_data
->exited
);
8688 io_sq_thread_finish(ctx
);
8692 static inline void __io_unaccount_mem(struct user_struct
*user
,
8693 unsigned long nr_pages
)
8695 atomic_long_sub(nr_pages
, &user
->locked_vm
);
8698 static inline int __io_account_mem(struct user_struct
*user
,
8699 unsigned long nr_pages
)
8701 unsigned long page_limit
, cur_pages
, new_pages
;
8703 /* Don't allow more pages than we can safely lock */
8704 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
8707 cur_pages
= atomic_long_read(&user
->locked_vm
);
8708 new_pages
= cur_pages
+ nr_pages
;
8709 if (new_pages
> page_limit
)
8711 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
8712 new_pages
) != cur_pages
);
8717 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8720 __io_unaccount_mem(ctx
->user
, nr_pages
);
8722 if (ctx
->mm_account
)
8723 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8726 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8731 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8736 if (ctx
->mm_account
)
8737 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8742 static void io_mem_free(void *ptr
)
8749 page
= virt_to_head_page(ptr
);
8750 if (put_page_testzero(page
))
8751 free_compound_page(page
);
8754 static void *io_mem_alloc(size_t size
)
8756 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8757 __GFP_NORETRY
| __GFP_ACCOUNT
;
8759 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8762 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8765 struct io_rings
*rings
;
8766 size_t off
, sq_array_size
;
8768 off
= struct_size(rings
, cqes
, cq_entries
);
8769 if (off
== SIZE_MAX
)
8773 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8781 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8782 if (sq_array_size
== SIZE_MAX
)
8785 if (check_add_overflow(off
, sq_array_size
, &off
))
8791 static void io_buffer_unmap(struct io_ring_ctx
*ctx
, struct io_mapped_ubuf
**slot
)
8793 struct io_mapped_ubuf
*imu
= *slot
;
8796 if (imu
!= ctx
->dummy_ubuf
) {
8797 for (i
= 0; i
< imu
->nr_bvecs
; i
++)
8798 unpin_user_page(imu
->bvec
[i
].bv_page
);
8799 if (imu
->acct_pages
)
8800 io_unaccount_mem(ctx
, imu
->acct_pages
);
8806 static void io_rsrc_buf_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
8808 io_buffer_unmap(ctx
, &prsrc
->buf
);
8812 static void __io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8816 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++)
8817 io_buffer_unmap(ctx
, &ctx
->user_bufs
[i
]);
8818 kfree(ctx
->user_bufs
);
8819 io_rsrc_data_free(ctx
->buf_data
);
8820 ctx
->user_bufs
= NULL
;
8821 ctx
->buf_data
= NULL
;
8822 ctx
->nr_user_bufs
= 0;
8825 static int io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8832 ret
= io_rsrc_ref_quiesce(ctx
->buf_data
, ctx
);
8834 __io_sqe_buffers_unregister(ctx
);
8838 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8839 void __user
*arg
, unsigned index
)
8841 struct iovec __user
*src
;
8843 #ifdef CONFIG_COMPAT
8845 struct compat_iovec __user
*ciovs
;
8846 struct compat_iovec ciov
;
8848 ciovs
= (struct compat_iovec __user
*) arg
;
8849 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8852 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8853 dst
->iov_len
= ciov
.iov_len
;
8857 src
= (struct iovec __user
*) arg
;
8858 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8864 * Not super efficient, but this is just a registration time. And we do cache
8865 * the last compound head, so generally we'll only do a full search if we don't
8868 * We check if the given compound head page has already been accounted, to
8869 * avoid double accounting it. This allows us to account the full size of the
8870 * page, not just the constituent pages of a huge page.
8872 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8873 int nr_pages
, struct page
*hpage
)
8877 /* check current page array */
8878 for (i
= 0; i
< nr_pages
; i
++) {
8879 if (!PageCompound(pages
[i
]))
8881 if (compound_head(pages
[i
]) == hpage
)
8885 /* check previously registered pages */
8886 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8887 struct io_mapped_ubuf
*imu
= ctx
->user_bufs
[i
];
8889 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8890 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8892 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8900 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8901 int nr_pages
, struct io_mapped_ubuf
*imu
,
8902 struct page
**last_hpage
)
8906 imu
->acct_pages
= 0;
8907 for (i
= 0; i
< nr_pages
; i
++) {
8908 if (!PageCompound(pages
[i
])) {
8913 hpage
= compound_head(pages
[i
]);
8914 if (hpage
== *last_hpage
)
8916 *last_hpage
= hpage
;
8917 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8919 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8923 if (!imu
->acct_pages
)
8926 ret
= io_account_mem(ctx
, imu
->acct_pages
);
8928 imu
->acct_pages
= 0;
8932 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, struct iovec
*iov
,
8933 struct io_mapped_ubuf
**pimu
,
8934 struct page
**last_hpage
)
8936 struct io_mapped_ubuf
*imu
= NULL
;
8937 struct vm_area_struct
**vmas
= NULL
;
8938 struct page
**pages
= NULL
;
8939 unsigned long off
, start
, end
, ubuf
;
8941 int ret
, pret
, nr_pages
, i
;
8943 if (!iov
->iov_base
) {
8944 *pimu
= ctx
->dummy_ubuf
;
8948 ubuf
= (unsigned long) iov
->iov_base
;
8949 end
= (ubuf
+ iov
->iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8950 start
= ubuf
>> PAGE_SHIFT
;
8951 nr_pages
= end
- start
;
8956 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*), GFP_KERNEL
);
8960 vmas
= kvmalloc_array(nr_pages
, sizeof(struct vm_area_struct
*),
8965 imu
= kvmalloc(struct_size(imu
, bvec
, nr_pages
), GFP_KERNEL
);
8970 mmap_read_lock(current
->mm
);
8971 pret
= pin_user_pages(ubuf
, nr_pages
, FOLL_WRITE
| FOLL_LONGTERM
,
8973 if (pret
== nr_pages
) {
8974 /* don't support file backed memory */
8975 for (i
= 0; i
< nr_pages
; i
++) {
8976 struct vm_area_struct
*vma
= vmas
[i
];
8978 if (vma_is_shmem(vma
))
8981 !is_file_hugepages(vma
->vm_file
)) {
8987 ret
= pret
< 0 ? pret
: -EFAULT
;
8989 mmap_read_unlock(current
->mm
);
8992 * if we did partial map, or found file backed vmas,
8993 * release any pages we did get
8996 unpin_user_pages(pages
, pret
);
9000 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, last_hpage
);
9002 unpin_user_pages(pages
, pret
);
9006 off
= ubuf
& ~PAGE_MASK
;
9007 size
= iov
->iov_len
;
9008 for (i
= 0; i
< nr_pages
; i
++) {
9011 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
9012 imu
->bvec
[i
].bv_page
= pages
[i
];
9013 imu
->bvec
[i
].bv_len
= vec_len
;
9014 imu
->bvec
[i
].bv_offset
= off
;
9018 /* store original address for later verification */
9020 imu
->ubuf_end
= ubuf
+ iov
->iov_len
;
9021 imu
->nr_bvecs
= nr_pages
;
9032 static int io_buffers_map_alloc(struct io_ring_ctx
*ctx
, unsigned int nr_args
)
9034 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(*ctx
->user_bufs
), GFP_KERNEL
);
9035 return ctx
->user_bufs
? 0 : -ENOMEM
;
9038 static int io_buffer_validate(struct iovec
*iov
)
9040 unsigned long tmp
, acct_len
= iov
->iov_len
+ (PAGE_SIZE
- 1);
9043 * Don't impose further limits on the size and buffer
9044 * constraints here, we'll -EINVAL later when IO is
9045 * submitted if they are wrong.
9048 return iov
->iov_len
? -EFAULT
: 0;
9052 /* arbitrary limit, but we need something */
9053 if (iov
->iov_len
> SZ_1G
)
9056 if (check_add_overflow((unsigned long)iov
->iov_base
, acct_len
, &tmp
))
9062 static int io_sqe_buffers_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
9063 unsigned int nr_args
, u64 __user
*tags
)
9065 struct page
*last_hpage
= NULL
;
9066 struct io_rsrc_data
*data
;
9072 if (!nr_args
|| nr_args
> IORING_MAX_REG_BUFFERS
)
9074 ret
= io_rsrc_node_switch_start(ctx
);
9077 ret
= io_rsrc_data_alloc(ctx
, io_rsrc_buf_put
, tags
, nr_args
, &data
);
9080 ret
= io_buffers_map_alloc(ctx
, nr_args
);
9082 io_rsrc_data_free(data
);
9086 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_bufs
++) {
9087 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
9090 ret
= io_buffer_validate(&iov
);
9093 if (!iov
.iov_base
&& *io_get_tag_slot(data
, i
)) {
9098 ret
= io_sqe_buffer_register(ctx
, &iov
, &ctx
->user_bufs
[i
],
9104 WARN_ON_ONCE(ctx
->buf_data
);
9106 ctx
->buf_data
= data
;
9108 __io_sqe_buffers_unregister(ctx
);
9110 io_rsrc_node_switch(ctx
, NULL
);
9114 static int __io_sqe_buffers_update(struct io_ring_ctx
*ctx
,
9115 struct io_uring_rsrc_update2
*up
,
9116 unsigned int nr_args
)
9118 u64 __user
*tags
= u64_to_user_ptr(up
->tags
);
9119 struct iovec iov
, __user
*iovs
= u64_to_user_ptr(up
->data
);
9120 struct page
*last_hpage
= NULL
;
9121 bool needs_switch
= false;
9127 if (up
->offset
+ nr_args
> ctx
->nr_user_bufs
)
9130 for (done
= 0; done
< nr_args
; done
++) {
9131 struct io_mapped_ubuf
*imu
;
9132 int offset
= up
->offset
+ done
;
9135 err
= io_copy_iov(ctx
, &iov
, iovs
, done
);
9138 if (tags
&& copy_from_user(&tag
, &tags
[done
], sizeof(tag
))) {
9142 err
= io_buffer_validate(&iov
);
9145 if (!iov
.iov_base
&& tag
) {
9149 err
= io_sqe_buffer_register(ctx
, &iov
, &imu
, &last_hpage
);
9153 i
= array_index_nospec(offset
, ctx
->nr_user_bufs
);
9154 if (ctx
->user_bufs
[i
] != ctx
->dummy_ubuf
) {
9155 err
= io_queue_rsrc_removal(ctx
->buf_data
, offset
,
9156 ctx
->rsrc_node
, ctx
->user_bufs
[i
]);
9157 if (unlikely(err
)) {
9158 io_buffer_unmap(ctx
, &imu
);
9161 ctx
->user_bufs
[i
] = NULL
;
9162 needs_switch
= true;
9165 ctx
->user_bufs
[i
] = imu
;
9166 *io_get_tag_slot(ctx
->buf_data
, offset
) = tag
;
9170 io_rsrc_node_switch(ctx
, ctx
->buf_data
);
9171 return done
? done
: err
;
9174 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
9176 __s32 __user
*fds
= arg
;
9182 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
9185 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
9186 if (IS_ERR(ctx
->cq_ev_fd
)) {
9187 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
9189 ctx
->cq_ev_fd
= NULL
;
9196 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
9198 if (ctx
->cq_ev_fd
) {
9199 eventfd_ctx_put(ctx
->cq_ev_fd
);
9200 ctx
->cq_ev_fd
= NULL
;
9207 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
9209 struct io_buffer
*buf
;
9210 unsigned long index
;
9212 xa_for_each(&ctx
->io_buffers
, index
, buf
) {
9213 __io_remove_buffers(ctx
, buf
, index
, -1U);
9218 static void io_req_cache_free(struct list_head
*list
)
9220 struct io_kiocb
*req
, *nxt
;
9222 list_for_each_entry_safe(req
, nxt
, list
, inflight_entry
) {
9223 list_del(&req
->inflight_entry
);
9224 kmem_cache_free(req_cachep
, req
);
9228 static void io_req_caches_free(struct io_ring_ctx
*ctx
)
9230 struct io_submit_state
*state
= &ctx
->submit_state
;
9232 mutex_lock(&ctx
->uring_lock
);
9234 if (state
->free_reqs
) {
9235 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
9236 state
->free_reqs
= 0;
9239 io_flush_cached_locked_reqs(ctx
, state
);
9240 io_req_cache_free(&state
->free_list
);
9241 mutex_unlock(&ctx
->uring_lock
);
9244 static void io_wait_rsrc_data(struct io_rsrc_data
*data
)
9246 if (data
&& !atomic_dec_and_test(&data
->refs
))
9247 wait_for_completion(&data
->done
);
9250 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
9252 io_sq_thread_finish(ctx
);
9254 if (ctx
->mm_account
) {
9255 mmdrop(ctx
->mm_account
);
9256 ctx
->mm_account
= NULL
;
9259 /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */
9260 io_wait_rsrc_data(ctx
->buf_data
);
9261 io_wait_rsrc_data(ctx
->file_data
);
9263 mutex_lock(&ctx
->uring_lock
);
9265 __io_sqe_buffers_unregister(ctx
);
9267 __io_sqe_files_unregister(ctx
);
9269 __io_cqring_overflow_flush(ctx
, true);
9270 mutex_unlock(&ctx
->uring_lock
);
9271 io_eventfd_unregister(ctx
);
9272 io_destroy_buffers(ctx
);
9274 put_cred(ctx
->sq_creds
);
9276 /* there are no registered resources left, nobody uses it */
9278 io_rsrc_node_destroy(ctx
->rsrc_node
);
9279 if (ctx
->rsrc_backup_node
)
9280 io_rsrc_node_destroy(ctx
->rsrc_backup_node
);
9281 flush_delayed_work(&ctx
->rsrc_put_work
);
9283 WARN_ON_ONCE(!list_empty(&ctx
->rsrc_ref_list
));
9284 WARN_ON_ONCE(!llist_empty(&ctx
->rsrc_put_llist
));
9286 #if defined(CONFIG_UNIX)
9287 if (ctx
->ring_sock
) {
9288 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
9289 sock_release(ctx
->ring_sock
);
9292 WARN_ON_ONCE(!list_empty(&ctx
->ltimeout_list
));
9294 io_mem_free(ctx
->rings
);
9295 io_mem_free(ctx
->sq_sqes
);
9297 percpu_ref_exit(&ctx
->refs
);
9298 free_uid(ctx
->user
);
9299 io_req_caches_free(ctx
);
9301 io_wq_put_hash(ctx
->hash_map
);
9302 kfree(ctx
->cancel_hash
);
9303 kfree(ctx
->dummy_ubuf
);
9307 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
9309 struct io_ring_ctx
*ctx
= file
->private_data
;
9312 poll_wait(file
, &ctx
->poll_wait
, wait
);
9314 * synchronizes with barrier from wq_has_sleeper call in
9318 if (!io_sqring_full(ctx
))
9319 mask
|= EPOLLOUT
| EPOLLWRNORM
;
9322 * Don't flush cqring overflow list here, just do a simple check.
9323 * Otherwise there could possible be ABBA deadlock:
9326 * lock(&ctx->uring_lock);
9328 * lock(&ctx->uring_lock);
9331 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
9332 * pushs them to do the flush.
9334 if (io_cqring_events(ctx
) || test_bit(0, &ctx
->check_cq_overflow
))
9335 mask
|= EPOLLIN
| EPOLLRDNORM
;
9340 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
9342 const struct cred
*creds
;
9344 creds
= xa_erase(&ctx
->personalities
, id
);
9353 struct io_tctx_exit
{
9354 struct callback_head task_work
;
9355 struct completion completion
;
9356 struct io_ring_ctx
*ctx
;
9359 static void io_tctx_exit_cb(struct callback_head
*cb
)
9361 struct io_uring_task
*tctx
= current
->io_uring
;
9362 struct io_tctx_exit
*work
;
9364 work
= container_of(cb
, struct io_tctx_exit
, task_work
);
9366 * When @in_idle, we're in cancellation and it's racy to remove the
9367 * node. It'll be removed by the end of cancellation, just ignore it.
9369 if (!atomic_read(&tctx
->in_idle
))
9370 io_uring_del_tctx_node((unsigned long)work
->ctx
);
9371 complete(&work
->completion
);
9374 static bool io_cancel_ctx_cb(struct io_wq_work
*work
, void *data
)
9376 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
9378 return req
->ctx
== data
;
9381 static void io_ring_exit_work(struct work_struct
*work
)
9383 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
, exit_work
);
9384 unsigned long timeout
= jiffies
+ HZ
* 60 * 5;
9385 unsigned long interval
= HZ
/ 20;
9386 struct io_tctx_exit exit
;
9387 struct io_tctx_node
*node
;
9391 * If we're doing polled IO and end up having requests being
9392 * submitted async (out-of-line), then completions can come in while
9393 * we're waiting for refs to drop. We need to reap these manually,
9394 * as nobody else will be looking for them.
9397 io_uring_try_cancel_requests(ctx
, NULL
, true);
9399 struct io_sq_data
*sqd
= ctx
->sq_data
;
9400 struct task_struct
*tsk
;
9402 io_sq_thread_park(sqd
);
9404 if (tsk
&& tsk
->io_uring
&& tsk
->io_uring
->io_wq
)
9405 io_wq_cancel_cb(tsk
->io_uring
->io_wq
,
9406 io_cancel_ctx_cb
, ctx
, true);
9407 io_sq_thread_unpark(sqd
);
9410 if (WARN_ON_ONCE(time_after(jiffies
, timeout
))) {
9411 /* there is little hope left, don't run it too often */
9414 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, interval
));
9416 init_completion(&exit
.completion
);
9417 init_task_work(&exit
.task_work
, io_tctx_exit_cb
);
9420 * Some may use context even when all refs and requests have been put,
9421 * and they are free to do so while still holding uring_lock or
9422 * completion_lock, see io_req_task_submit(). Apart from other work,
9423 * this lock/unlock section also waits them to finish.
9425 mutex_lock(&ctx
->uring_lock
);
9426 while (!list_empty(&ctx
->tctx_list
)) {
9427 WARN_ON_ONCE(time_after(jiffies
, timeout
));
9429 node
= list_first_entry(&ctx
->tctx_list
, struct io_tctx_node
,
9431 /* don't spin on a single task if cancellation failed */
9432 list_rotate_left(&ctx
->tctx_list
);
9433 ret
= task_work_add(node
->task
, &exit
.task_work
, TWA_SIGNAL
);
9434 if (WARN_ON_ONCE(ret
))
9436 wake_up_process(node
->task
);
9438 mutex_unlock(&ctx
->uring_lock
);
9439 wait_for_completion(&exit
.completion
);
9440 mutex_lock(&ctx
->uring_lock
);
9442 mutex_unlock(&ctx
->uring_lock
);
9443 spin_lock(&ctx
->completion_lock
);
9444 spin_unlock(&ctx
->completion_lock
);
9446 io_ring_ctx_free(ctx
);
9449 /* Returns true if we found and killed one or more timeouts */
9450 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
9453 struct io_kiocb
*req
, *tmp
;
9456 spin_lock(&ctx
->completion_lock
);
9457 spin_lock_irq(&ctx
->timeout_lock
);
9458 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
9459 if (io_match_task(req
, tsk
, cancel_all
)) {
9460 io_kill_timeout(req
, -ECANCELED
);
9464 spin_unlock_irq(&ctx
->timeout_lock
);
9466 io_commit_cqring(ctx
);
9467 spin_unlock(&ctx
->completion_lock
);
9469 io_cqring_ev_posted(ctx
);
9470 return canceled
!= 0;
9473 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
9475 unsigned long index
;
9476 struct creds
*creds
;
9478 mutex_lock(&ctx
->uring_lock
);
9479 percpu_ref_kill(&ctx
->refs
);
9481 __io_cqring_overflow_flush(ctx
, true);
9482 xa_for_each(&ctx
->personalities
, index
, creds
)
9483 io_unregister_personality(ctx
, index
);
9484 mutex_unlock(&ctx
->uring_lock
);
9486 io_kill_timeouts(ctx
, NULL
, true);
9487 io_poll_remove_all(ctx
, NULL
, true);
9489 /* if we failed setting up the ctx, we might not have any rings */
9490 io_iopoll_try_reap_events(ctx
);
9492 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
9494 * Use system_unbound_wq to avoid spawning tons of event kworkers
9495 * if we're exiting a ton of rings at the same time. It just adds
9496 * noise and overhead, there's no discernable change in runtime
9497 * over using system_wq.
9499 queue_work(system_unbound_wq
, &ctx
->exit_work
);
9502 static int io_uring_release(struct inode
*inode
, struct file
*file
)
9504 struct io_ring_ctx
*ctx
= file
->private_data
;
9506 file
->private_data
= NULL
;
9507 io_ring_ctx_wait_and_kill(ctx
);
9511 struct io_task_cancel
{
9512 struct task_struct
*task
;
9516 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
9518 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
9519 struct io_task_cancel
*cancel
= data
;
9522 if (!cancel
->all
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
9523 struct io_ring_ctx
*ctx
= req
->ctx
;
9525 /* protect against races with linked timeouts */
9526 spin_lock(&ctx
->completion_lock
);
9527 ret
= io_match_task(req
, cancel
->task
, cancel
->all
);
9528 spin_unlock(&ctx
->completion_lock
);
9530 ret
= io_match_task(req
, cancel
->task
, cancel
->all
);
9535 static bool io_cancel_defer_files(struct io_ring_ctx
*ctx
,
9536 struct task_struct
*task
, bool cancel_all
)
9538 struct io_defer_entry
*de
;
9541 spin_lock(&ctx
->completion_lock
);
9542 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
9543 if (io_match_task(de
->req
, task
, cancel_all
)) {
9544 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
9548 spin_unlock(&ctx
->completion_lock
);
9549 if (list_empty(&list
))
9552 while (!list_empty(&list
)) {
9553 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
9554 list_del_init(&de
->list
);
9555 io_req_complete_failed(de
->req
, -ECANCELED
);
9561 static bool io_uring_try_cancel_iowq(struct io_ring_ctx
*ctx
)
9563 struct io_tctx_node
*node
;
9564 enum io_wq_cancel cret
;
9567 mutex_lock(&ctx
->uring_lock
);
9568 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
9569 struct io_uring_task
*tctx
= node
->task
->io_uring
;
9572 * io_wq will stay alive while we hold uring_lock, because it's
9573 * killed after ctx nodes, which requires to take the lock.
9575 if (!tctx
|| !tctx
->io_wq
)
9577 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_ctx_cb
, ctx
, true);
9578 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
9580 mutex_unlock(&ctx
->uring_lock
);
9585 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
9586 struct task_struct
*task
,
9589 struct io_task_cancel cancel
= { .task
= task
, .all
= cancel_all
, };
9590 struct io_uring_task
*tctx
= task
? task
->io_uring
: NULL
;
9593 enum io_wq_cancel cret
;
9597 ret
|= io_uring_try_cancel_iowq(ctx
);
9598 } else if (tctx
&& tctx
->io_wq
) {
9600 * Cancels requests of all rings, not only @ctx, but
9601 * it's fine as the task is in exit/exec.
9603 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_task_cb
,
9605 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
9608 /* SQPOLL thread does its own polling */
9609 if ((!(ctx
->flags
& IORING_SETUP_SQPOLL
) && cancel_all
) ||
9610 (ctx
->sq_data
&& ctx
->sq_data
->thread
== current
)) {
9611 while (!list_empty_careful(&ctx
->iopoll_list
)) {
9612 io_iopoll_try_reap_events(ctx
);
9617 ret
|= io_cancel_defer_files(ctx
, task
, cancel_all
);
9618 ret
|= io_poll_remove_all(ctx
, task
, cancel_all
);
9619 ret
|= io_kill_timeouts(ctx
, task
, cancel_all
);
9621 ret
|= io_run_task_work();
9628 static int __io_uring_add_tctx_node(struct io_ring_ctx
*ctx
)
9630 struct io_uring_task
*tctx
= current
->io_uring
;
9631 struct io_tctx_node
*node
;
9634 if (unlikely(!tctx
)) {
9635 ret
= io_uring_alloc_task_context(current
, ctx
);
9639 tctx
= current
->io_uring
;
9640 if (ctx
->iowq_limits_set
) {
9641 unsigned int limits
[2] = { ctx
->iowq_limits
[0],
9642 ctx
->iowq_limits
[1], };
9644 ret
= io_wq_max_workers(tctx
->io_wq
, limits
);
9649 if (!xa_load(&tctx
->xa
, (unsigned long)ctx
)) {
9650 node
= kmalloc(sizeof(*node
), GFP_KERNEL
);
9654 node
->task
= current
;
9656 ret
= xa_err(xa_store(&tctx
->xa
, (unsigned long)ctx
,
9663 mutex_lock(&ctx
->uring_lock
);
9664 list_add(&node
->ctx_node
, &ctx
->tctx_list
);
9665 mutex_unlock(&ctx
->uring_lock
);
9672 * Note that this task has used io_uring. We use it for cancelation purposes.
9674 static inline int io_uring_add_tctx_node(struct io_ring_ctx
*ctx
)
9676 struct io_uring_task
*tctx
= current
->io_uring
;
9678 if (likely(tctx
&& tctx
->last
== ctx
))
9680 return __io_uring_add_tctx_node(ctx
);
9684 * Remove this io_uring_file -> task mapping.
9686 static void io_uring_del_tctx_node(unsigned long index
)
9688 struct io_uring_task
*tctx
= current
->io_uring
;
9689 struct io_tctx_node
*node
;
9693 node
= xa_erase(&tctx
->xa
, index
);
9697 WARN_ON_ONCE(current
!= node
->task
);
9698 WARN_ON_ONCE(list_empty(&node
->ctx_node
));
9700 mutex_lock(&node
->ctx
->uring_lock
);
9701 list_del(&node
->ctx_node
);
9702 mutex_unlock(&node
->ctx
->uring_lock
);
9704 if (tctx
->last
== node
->ctx
)
9709 static void io_uring_clean_tctx(struct io_uring_task
*tctx
)
9711 struct io_wq
*wq
= tctx
->io_wq
;
9712 struct io_tctx_node
*node
;
9713 unsigned long index
;
9715 xa_for_each(&tctx
->xa
, index
, node
) {
9716 io_uring_del_tctx_node(index
);
9721 * Must be after io_uring_del_task_file() (removes nodes under
9722 * uring_lock) to avoid race with io_uring_try_cancel_iowq().
9724 io_wq_put_and_exit(wq
);
9729 static s64
tctx_inflight(struct io_uring_task
*tctx
, bool tracked
)
9732 return atomic_read(&tctx
->inflight_tracked
);
9733 return percpu_counter_sum(&tctx
->inflight
);
9736 static void io_uring_drop_tctx_refs(struct task_struct
*task
)
9738 struct io_uring_task
*tctx
= task
->io_uring
;
9739 unsigned int refs
= tctx
->cached_refs
;
9742 tctx
->cached_refs
= 0;
9743 percpu_counter_sub(&tctx
->inflight
, refs
);
9744 put_task_struct_many(task
, refs
);
9749 * Find any io_uring ctx that this task has registered or done IO on, and cancel
9750 * requests. @sqd should be not-null IIF it's an SQPOLL thread cancellation.
9752 static void io_uring_cancel_generic(bool cancel_all
, struct io_sq_data
*sqd
)
9754 struct io_uring_task
*tctx
= current
->io_uring
;
9755 struct io_ring_ctx
*ctx
;
9759 WARN_ON_ONCE(sqd
&& sqd
->thread
!= current
);
9761 if (!current
->io_uring
)
9764 io_wq_exit_start(tctx
->io_wq
);
9766 atomic_inc(&tctx
->in_idle
);
9768 io_uring_drop_tctx_refs(current
);
9769 /* read completions before cancelations */
9770 inflight
= tctx_inflight(tctx
, !cancel_all
);
9775 struct io_tctx_node
*node
;
9776 unsigned long index
;
9778 xa_for_each(&tctx
->xa
, index
, node
) {
9779 /* sqpoll task will cancel all its requests */
9780 if (node
->ctx
->sq_data
)
9782 io_uring_try_cancel_requests(node
->ctx
, current
,
9786 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
9787 io_uring_try_cancel_requests(ctx
, current
,
9791 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
9792 io_uring_drop_tctx_refs(current
);
9794 * If we've seen completions, retry without waiting. This
9795 * avoids a race where a completion comes in before we did
9796 * prepare_to_wait().
9798 if (inflight
== tctx_inflight(tctx
, !cancel_all
))
9800 finish_wait(&tctx
->wait
, &wait
);
9802 atomic_dec(&tctx
->in_idle
);
9804 io_uring_clean_tctx(tctx
);
9806 /* for exec all current's requests should be gone, kill tctx */
9807 __io_uring_free(current
);
9811 void __io_uring_cancel(bool cancel_all
)
9813 io_uring_cancel_generic(cancel_all
, NULL
);
9816 static void *io_uring_validate_mmap_request(struct file
*file
,
9817 loff_t pgoff
, size_t sz
)
9819 struct io_ring_ctx
*ctx
= file
->private_data
;
9820 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9825 case IORING_OFF_SQ_RING
:
9826 case IORING_OFF_CQ_RING
:
9829 case IORING_OFF_SQES
:
9833 return ERR_PTR(-EINVAL
);
9836 page
= virt_to_head_page(ptr
);
9837 if (sz
> page_size(page
))
9838 return ERR_PTR(-EINVAL
);
9845 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9847 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9851 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9853 return PTR_ERR(ptr
);
9855 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9856 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9859 #else /* !CONFIG_MMU */
9861 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9863 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9866 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9868 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9871 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9872 unsigned long addr
, unsigned long len
,
9873 unsigned long pgoff
, unsigned long flags
)
9877 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9879 return PTR_ERR(ptr
);
9881 return (unsigned long) ptr
;
9884 #endif /* !CONFIG_MMU */
9886 static int io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9891 if (!io_sqring_full(ctx
))
9893 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9895 if (!io_sqring_full(ctx
))
9898 } while (!signal_pending(current
));
9900 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9904 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9905 struct __kernel_timespec __user
**ts
,
9906 const sigset_t __user
**sig
)
9908 struct io_uring_getevents_arg arg
;
9911 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9912 * is just a pointer to the sigset_t.
9914 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9915 *sig
= (const sigset_t __user
*) argp
;
9921 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9922 * timespec and sigset_t pointers if good.
9924 if (*argsz
!= sizeof(arg
))
9926 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9928 *sig
= u64_to_user_ptr(arg
.sigmask
);
9929 *argsz
= arg
.sigmask_sz
;
9930 *ts
= u64_to_user_ptr(arg
.ts
);
9934 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9935 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9938 struct io_ring_ctx
*ctx
;
9945 if (unlikely(flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9946 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
)))
9950 if (unlikely(!f
.file
))
9954 if (unlikely(f
.file
->f_op
!= &io_uring_fops
))
9958 ctx
= f
.file
->private_data
;
9959 if (unlikely(!percpu_ref_tryget(&ctx
->refs
)))
9963 if (unlikely(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9967 * For SQ polling, the thread will do all submissions and completions.
9968 * Just return the requested submit count, and wake the thread if
9972 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9973 io_cqring_overflow_flush(ctx
);
9975 if (unlikely(ctx
->sq_data
->thread
== NULL
)) {
9979 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9980 wake_up(&ctx
->sq_data
->wait
);
9981 if (flags
& IORING_ENTER_SQ_WAIT
) {
9982 ret
= io_sqpoll_wait_sq(ctx
);
9986 submitted
= to_submit
;
9987 } else if (to_submit
) {
9988 ret
= io_uring_add_tctx_node(ctx
);
9991 mutex_lock(&ctx
->uring_lock
);
9992 submitted
= io_submit_sqes(ctx
, to_submit
);
9993 mutex_unlock(&ctx
->uring_lock
);
9995 if (submitted
!= to_submit
)
9998 if (flags
& IORING_ENTER_GETEVENTS
) {
9999 const sigset_t __user
*sig
;
10000 struct __kernel_timespec __user
*ts
;
10002 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
10006 min_complete
= min(min_complete
, ctx
->cq_entries
);
10009 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
10010 * space applications don't need to do io completion events
10011 * polling again, they can rely on io_sq_thread to do polling
10012 * work, which can reduce cpu usage and uring_lock contention.
10014 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
10015 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
10016 ret
= io_iopoll_check(ctx
, min_complete
);
10018 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
10023 percpu_ref_put(&ctx
->refs
);
10026 return submitted
? submitted
: ret
;
10029 #ifdef CONFIG_PROC_FS
10030 static int io_uring_show_cred(struct seq_file
*m
, unsigned int id
,
10031 const struct cred
*cred
)
10033 struct user_namespace
*uns
= seq_user_ns(m
);
10034 struct group_info
*gi
;
10039 seq_printf(m
, "%5d\n", id
);
10040 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
10041 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
10042 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
10043 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
10044 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
10045 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
10046 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
10047 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
10048 seq_puts(m
, "\n\tGroups:\t");
10049 gi
= cred
->group_info
;
10050 for (g
= 0; g
< gi
->ngroups
; g
++) {
10051 seq_put_decimal_ull(m
, g
? " " : "",
10052 from_kgid_munged(uns
, gi
->gid
[g
]));
10054 seq_puts(m
, "\n\tCapEff:\t");
10055 cap
= cred
->cap_effective
;
10056 CAP_FOR_EACH_U32(__capi
)
10057 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
10062 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
10064 struct io_sq_data
*sq
= NULL
;
10069 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
10070 * since fdinfo case grabs it in the opposite direction of normal use
10071 * cases. If we fail to get the lock, we just don't iterate any
10072 * structures that could be going away outside the io_uring mutex.
10074 has_lock
= mutex_trylock(&ctx
->uring_lock
);
10076 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
)) {
10082 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
10083 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
10084 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
10085 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
10086 struct file
*f
= io_file_from_index(ctx
, i
);
10089 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
10091 seq_printf(m
, "%5u: <none>\n", i
);
10093 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
10094 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
10095 struct io_mapped_ubuf
*buf
= ctx
->user_bufs
[i
];
10096 unsigned int len
= buf
->ubuf_end
- buf
->ubuf
;
10098 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
, len
);
10100 if (has_lock
&& !xa_empty(&ctx
->personalities
)) {
10101 unsigned long index
;
10102 const struct cred
*cred
;
10104 seq_printf(m
, "Personalities:\n");
10105 xa_for_each(&ctx
->personalities
, index
, cred
)
10106 io_uring_show_cred(m
, index
, cred
);
10108 seq_printf(m
, "PollList:\n");
10109 spin_lock(&ctx
->completion_lock
);
10110 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
10111 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
10112 struct io_kiocb
*req
;
10114 hlist_for_each_entry(req
, list
, hash_node
)
10115 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
10116 req
->task
->task_works
!= NULL
);
10118 spin_unlock(&ctx
->completion_lock
);
10120 mutex_unlock(&ctx
->uring_lock
);
10123 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
10125 struct io_ring_ctx
*ctx
= f
->private_data
;
10127 if (percpu_ref_tryget(&ctx
->refs
)) {
10128 __io_uring_show_fdinfo(ctx
, m
);
10129 percpu_ref_put(&ctx
->refs
);
10134 static const struct file_operations io_uring_fops
= {
10135 .release
= io_uring_release
,
10136 .mmap
= io_uring_mmap
,
10138 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
10139 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
10141 .poll
= io_uring_poll
,
10142 #ifdef CONFIG_PROC_FS
10143 .show_fdinfo
= io_uring_show_fdinfo
,
10147 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
10148 struct io_uring_params
*p
)
10150 struct io_rings
*rings
;
10151 size_t size
, sq_array_offset
;
10153 /* make sure these are sane, as we already accounted them */
10154 ctx
->sq_entries
= p
->sq_entries
;
10155 ctx
->cq_entries
= p
->cq_entries
;
10157 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
10158 if (size
== SIZE_MAX
)
10161 rings
= io_mem_alloc(size
);
10165 ctx
->rings
= rings
;
10166 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
10167 rings
->sq_ring_mask
= p
->sq_entries
- 1;
10168 rings
->cq_ring_mask
= p
->cq_entries
- 1;
10169 rings
->sq_ring_entries
= p
->sq_entries
;
10170 rings
->cq_ring_entries
= p
->cq_entries
;
10172 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
10173 if (size
== SIZE_MAX
) {
10174 io_mem_free(ctx
->rings
);
10179 ctx
->sq_sqes
= io_mem_alloc(size
);
10180 if (!ctx
->sq_sqes
) {
10181 io_mem_free(ctx
->rings
);
10189 static int io_uring_install_fd(struct io_ring_ctx
*ctx
, struct file
*file
)
10193 fd
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
10197 ret
= io_uring_add_tctx_node(ctx
);
10202 fd_install(fd
, file
);
10207 * Allocate an anonymous fd, this is what constitutes the application
10208 * visible backing of an io_uring instance. The application mmaps this
10209 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
10210 * we have to tie this fd to a socket for file garbage collection purposes.
10212 static struct file
*io_uring_get_file(struct io_ring_ctx
*ctx
)
10215 #if defined(CONFIG_UNIX)
10218 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
10221 return ERR_PTR(ret
);
10224 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
10225 O_RDWR
| O_CLOEXEC
);
10226 #if defined(CONFIG_UNIX)
10227 if (IS_ERR(file
)) {
10228 sock_release(ctx
->ring_sock
);
10229 ctx
->ring_sock
= NULL
;
10231 ctx
->ring_sock
->file
= file
;
10237 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
10238 struct io_uring_params __user
*params
)
10240 struct io_ring_ctx
*ctx
;
10246 if (entries
> IORING_MAX_ENTRIES
) {
10247 if (!(p
->flags
& IORING_SETUP_CLAMP
))
10249 entries
= IORING_MAX_ENTRIES
;
10253 * Use twice as many entries for the CQ ring. It's possible for the
10254 * application to drive a higher depth than the size of the SQ ring,
10255 * since the sqes are only used at submission time. This allows for
10256 * some flexibility in overcommitting a bit. If the application has
10257 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
10258 * of CQ ring entries manually.
10260 p
->sq_entries
= roundup_pow_of_two(entries
);
10261 if (p
->flags
& IORING_SETUP_CQSIZE
) {
10263 * If IORING_SETUP_CQSIZE is set, we do the same roundup
10264 * to a power-of-two, if it isn't already. We do NOT impose
10265 * any cq vs sq ring sizing.
10267 if (!p
->cq_entries
)
10269 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
10270 if (!(p
->flags
& IORING_SETUP_CLAMP
))
10272 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
10274 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
10275 if (p
->cq_entries
< p
->sq_entries
)
10278 p
->cq_entries
= 2 * p
->sq_entries
;
10281 ctx
= io_ring_ctx_alloc(p
);
10284 ctx
->compat
= in_compat_syscall();
10285 if (!capable(CAP_IPC_LOCK
))
10286 ctx
->user
= get_uid(current_user());
10289 * This is just grabbed for accounting purposes. When a process exits,
10290 * the mm is exited and dropped before the files, hence we need to hang
10291 * on to this mm purely for the purposes of being able to unaccount
10292 * memory (locked/pinned vm). It's not used for anything else.
10294 mmgrab(current
->mm
);
10295 ctx
->mm_account
= current
->mm
;
10297 ret
= io_allocate_scq_urings(ctx
, p
);
10301 ret
= io_sq_offload_create(ctx
, p
);
10304 /* always set a rsrc node */
10305 ret
= io_rsrc_node_switch_start(ctx
);
10308 io_rsrc_node_switch(ctx
, NULL
);
10310 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
10311 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
10312 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
10313 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
10314 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
10315 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
10316 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
10317 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
10319 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
10320 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
10321 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
10322 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
10323 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
10324 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
10325 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
10326 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
10328 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
10329 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
10330 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
10331 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
10332 IORING_FEAT_EXT_ARG
| IORING_FEAT_NATIVE_WORKERS
|
10333 IORING_FEAT_RSRC_TAGS
;
10335 if (copy_to_user(params
, p
, sizeof(*p
))) {
10340 file
= io_uring_get_file(ctx
);
10341 if (IS_ERR(file
)) {
10342 ret
= PTR_ERR(file
);
10347 * Install ring fd as the very last thing, so we don't risk someone
10348 * having closed it before we finish setup
10350 ret
= io_uring_install_fd(ctx
, file
);
10352 /* fput will clean it up */
10357 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
10360 io_ring_ctx_wait_and_kill(ctx
);
10365 * Sets up an aio uring context, and returns the fd. Applications asks for a
10366 * ring size, we return the actual sq/cq ring sizes (among other things) in the
10367 * params structure passed in.
10369 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
10371 struct io_uring_params p
;
10374 if (copy_from_user(&p
, params
, sizeof(p
)))
10376 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
10381 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
10382 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
10383 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
10384 IORING_SETUP_R_DISABLED
))
10387 return io_uring_create(entries
, &p
, params
);
10390 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
10391 struct io_uring_params __user
*, params
)
10393 return io_uring_setup(entries
, params
);
10396 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
10398 struct io_uring_probe
*p
;
10402 size
= struct_size(p
, ops
, nr_args
);
10403 if (size
== SIZE_MAX
)
10405 p
= kzalloc(size
, GFP_KERNEL
);
10410 if (copy_from_user(p
, arg
, size
))
10413 if (memchr_inv(p
, 0, size
))
10416 p
->last_op
= IORING_OP_LAST
- 1;
10417 if (nr_args
> IORING_OP_LAST
)
10418 nr_args
= IORING_OP_LAST
;
10420 for (i
= 0; i
< nr_args
; i
++) {
10422 if (!io_op_defs
[i
].not_supported
)
10423 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
10428 if (copy_to_user(arg
, p
, size
))
10435 static int io_register_personality(struct io_ring_ctx
*ctx
)
10437 const struct cred
*creds
;
10441 creds
= get_current_cred();
10443 ret
= xa_alloc_cyclic(&ctx
->personalities
, &id
, (void *)creds
,
10444 XA_LIMIT(0, USHRT_MAX
), &ctx
->pers_next
, GFP_KERNEL
);
10452 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
10453 unsigned int nr_args
)
10455 struct io_uring_restriction
*res
;
10459 /* Restrictions allowed only if rings started disabled */
10460 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
10463 /* We allow only a single restrictions registration */
10464 if (ctx
->restrictions
.registered
)
10467 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
10470 size
= array_size(nr_args
, sizeof(*res
));
10471 if (size
== SIZE_MAX
)
10474 res
= memdup_user(arg
, size
);
10476 return PTR_ERR(res
);
10480 for (i
= 0; i
< nr_args
; i
++) {
10481 switch (res
[i
].opcode
) {
10482 case IORING_RESTRICTION_REGISTER_OP
:
10483 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
10488 __set_bit(res
[i
].register_op
,
10489 ctx
->restrictions
.register_op
);
10491 case IORING_RESTRICTION_SQE_OP
:
10492 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
10497 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
10499 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
10500 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
10502 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
10503 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
10512 /* Reset all restrictions if an error happened */
10514 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
10516 ctx
->restrictions
.registered
= true;
10522 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
10524 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
10527 if (ctx
->restrictions
.registered
)
10528 ctx
->restricted
= 1;
10530 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
10531 if (ctx
->sq_data
&& wq_has_sleeper(&ctx
->sq_data
->wait
))
10532 wake_up(&ctx
->sq_data
->wait
);
10536 static int __io_register_rsrc_update(struct io_ring_ctx
*ctx
, unsigned type
,
10537 struct io_uring_rsrc_update2
*up
,
10545 if (check_add_overflow(up
->offset
, nr_args
, &tmp
))
10547 err
= io_rsrc_node_switch_start(ctx
);
10552 case IORING_RSRC_FILE
:
10553 return __io_sqe_files_update(ctx
, up
, nr_args
);
10554 case IORING_RSRC_BUFFER
:
10555 return __io_sqe_buffers_update(ctx
, up
, nr_args
);
10560 static int io_register_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
10563 struct io_uring_rsrc_update2 up
;
10567 memset(&up
, 0, sizeof(up
));
10568 if (copy_from_user(&up
, arg
, sizeof(struct io_uring_rsrc_update
)))
10570 return __io_register_rsrc_update(ctx
, IORING_RSRC_FILE
, &up
, nr_args
);
10573 static int io_register_rsrc_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
10574 unsigned size
, unsigned type
)
10576 struct io_uring_rsrc_update2 up
;
10578 if (size
!= sizeof(up
))
10580 if (copy_from_user(&up
, arg
, sizeof(up
)))
10582 if (!up
.nr
|| up
.resv
)
10584 return __io_register_rsrc_update(ctx
, type
, &up
, up
.nr
);
10587 static int io_register_rsrc(struct io_ring_ctx
*ctx
, void __user
*arg
,
10588 unsigned int size
, unsigned int type
)
10590 struct io_uring_rsrc_register rr
;
10592 /* keep it extendible */
10593 if (size
!= sizeof(rr
))
10596 memset(&rr
, 0, sizeof(rr
));
10597 if (copy_from_user(&rr
, arg
, size
))
10599 if (!rr
.nr
|| rr
.resv
|| rr
.resv2
)
10603 case IORING_RSRC_FILE
:
10604 return io_sqe_files_register(ctx
, u64_to_user_ptr(rr
.data
),
10605 rr
.nr
, u64_to_user_ptr(rr
.tags
));
10606 case IORING_RSRC_BUFFER
:
10607 return io_sqe_buffers_register(ctx
, u64_to_user_ptr(rr
.data
),
10608 rr
.nr
, u64_to_user_ptr(rr
.tags
));
10613 static int io_register_iowq_aff(struct io_ring_ctx
*ctx
, void __user
*arg
,
10616 struct io_uring_task
*tctx
= current
->io_uring
;
10617 cpumask_var_t new_mask
;
10620 if (!tctx
|| !tctx
->io_wq
)
10623 if (!alloc_cpumask_var(&new_mask
, GFP_KERNEL
))
10626 cpumask_clear(new_mask
);
10627 if (len
> cpumask_size())
10628 len
= cpumask_size();
10630 if (copy_from_user(new_mask
, arg
, len
)) {
10631 free_cpumask_var(new_mask
);
10635 ret
= io_wq_cpu_affinity(tctx
->io_wq
, new_mask
);
10636 free_cpumask_var(new_mask
);
10640 static int io_unregister_iowq_aff(struct io_ring_ctx
*ctx
)
10642 struct io_uring_task
*tctx
= current
->io_uring
;
10644 if (!tctx
|| !tctx
->io_wq
)
10647 return io_wq_cpu_affinity(tctx
->io_wq
, NULL
);
10650 static int io_register_iowq_max_workers(struct io_ring_ctx
*ctx
,
10652 __must_hold(&ctx
->uring_lock
)
10654 struct io_tctx_node
*node
;
10655 struct io_uring_task
*tctx
= NULL
;
10656 struct io_sq_data
*sqd
= NULL
;
10657 __u32 new_count
[2];
10660 if (copy_from_user(new_count
, arg
, sizeof(new_count
)))
10662 for (i
= 0; i
< ARRAY_SIZE(new_count
); i
++)
10663 if (new_count
[i
] > INT_MAX
)
10666 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
10667 sqd
= ctx
->sq_data
;
10670 * Observe the correct sqd->lock -> ctx->uring_lock
10671 * ordering. Fine to drop uring_lock here, we hold
10672 * a ref to the ctx.
10674 refcount_inc(&sqd
->refs
);
10675 mutex_unlock(&ctx
->uring_lock
);
10676 mutex_lock(&sqd
->lock
);
10677 mutex_lock(&ctx
->uring_lock
);
10679 tctx
= sqd
->thread
->io_uring
;
10682 tctx
= current
->io_uring
;
10685 BUILD_BUG_ON(sizeof(new_count
) != sizeof(ctx
->iowq_limits
));
10687 memcpy(ctx
->iowq_limits
, new_count
, sizeof(new_count
));
10688 ctx
->iowq_limits_set
= true;
10691 if (tctx
&& tctx
->io_wq
) {
10692 ret
= io_wq_max_workers(tctx
->io_wq
, new_count
);
10696 memset(new_count
, 0, sizeof(new_count
));
10700 mutex_unlock(&sqd
->lock
);
10701 io_put_sq_data(sqd
);
10704 if (copy_to_user(arg
, new_count
, sizeof(new_count
)))
10707 /* that's it for SQPOLL, only the SQPOLL task creates requests */
10711 /* now propagate the restriction to all registered users */
10712 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
10713 struct io_uring_task
*tctx
= node
->task
->io_uring
;
10715 if (WARN_ON_ONCE(!tctx
->io_wq
))
10718 for (i
= 0; i
< ARRAY_SIZE(new_count
); i
++)
10719 new_count
[i
] = ctx
->iowq_limits
[i
];
10720 /* ignore errors, it always returns zero anyway */
10721 (void)io_wq_max_workers(tctx
->io_wq
, new_count
);
10726 mutex_unlock(&sqd
->lock
);
10727 io_put_sq_data(sqd
);
10732 static bool io_register_op_must_quiesce(int op
)
10735 case IORING_REGISTER_BUFFERS
:
10736 case IORING_UNREGISTER_BUFFERS
:
10737 case IORING_REGISTER_FILES
:
10738 case IORING_UNREGISTER_FILES
:
10739 case IORING_REGISTER_FILES_UPDATE
:
10740 case IORING_REGISTER_PROBE
:
10741 case IORING_REGISTER_PERSONALITY
:
10742 case IORING_UNREGISTER_PERSONALITY
:
10743 case IORING_REGISTER_FILES2
:
10744 case IORING_REGISTER_FILES_UPDATE2
:
10745 case IORING_REGISTER_BUFFERS2
:
10746 case IORING_REGISTER_BUFFERS_UPDATE
:
10747 case IORING_REGISTER_IOWQ_AFF
:
10748 case IORING_UNREGISTER_IOWQ_AFF
:
10749 case IORING_REGISTER_IOWQ_MAX_WORKERS
:
10756 static int io_ctx_quiesce(struct io_ring_ctx
*ctx
)
10760 percpu_ref_kill(&ctx
->refs
);
10763 * Drop uring mutex before waiting for references to exit. If another
10764 * thread is currently inside io_uring_enter() it might need to grab the
10765 * uring_lock to make progress. If we hold it here across the drain
10766 * wait, then we can deadlock. It's safe to drop the mutex here, since
10767 * no new references will come in after we've killed the percpu ref.
10769 mutex_unlock(&ctx
->uring_lock
);
10771 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
10774 ret
= io_run_task_work_sig();
10775 } while (ret
>= 0);
10776 mutex_lock(&ctx
->uring_lock
);
10779 io_refs_resurrect(&ctx
->refs
, &ctx
->ref_comp
);
10783 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
10784 void __user
*arg
, unsigned nr_args
)
10785 __releases(ctx
->uring_lock
)
10786 __acquires(ctx
->uring_lock
)
10791 * We're inside the ring mutex, if the ref is already dying, then
10792 * someone else killed the ctx or is already going through
10793 * io_uring_register().
10795 if (percpu_ref_is_dying(&ctx
->refs
))
10798 if (ctx
->restricted
) {
10799 if (opcode
>= IORING_REGISTER_LAST
)
10801 opcode
= array_index_nospec(opcode
, IORING_REGISTER_LAST
);
10802 if (!test_bit(opcode
, ctx
->restrictions
.register_op
))
10806 if (io_register_op_must_quiesce(opcode
)) {
10807 ret
= io_ctx_quiesce(ctx
);
10813 case IORING_REGISTER_BUFFERS
:
10814 ret
= io_sqe_buffers_register(ctx
, arg
, nr_args
, NULL
);
10816 case IORING_UNREGISTER_BUFFERS
:
10818 if (arg
|| nr_args
)
10820 ret
= io_sqe_buffers_unregister(ctx
);
10822 case IORING_REGISTER_FILES
:
10823 ret
= io_sqe_files_register(ctx
, arg
, nr_args
, NULL
);
10825 case IORING_UNREGISTER_FILES
:
10827 if (arg
|| nr_args
)
10829 ret
= io_sqe_files_unregister(ctx
);
10831 case IORING_REGISTER_FILES_UPDATE
:
10832 ret
= io_register_files_update(ctx
, arg
, nr_args
);
10834 case IORING_REGISTER_EVENTFD
:
10835 case IORING_REGISTER_EVENTFD_ASYNC
:
10839 ret
= io_eventfd_register(ctx
, arg
);
10842 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
10843 ctx
->eventfd_async
= 1;
10845 ctx
->eventfd_async
= 0;
10847 case IORING_UNREGISTER_EVENTFD
:
10849 if (arg
|| nr_args
)
10851 ret
= io_eventfd_unregister(ctx
);
10853 case IORING_REGISTER_PROBE
:
10855 if (!arg
|| nr_args
> 256)
10857 ret
= io_probe(ctx
, arg
, nr_args
);
10859 case IORING_REGISTER_PERSONALITY
:
10861 if (arg
|| nr_args
)
10863 ret
= io_register_personality(ctx
);
10865 case IORING_UNREGISTER_PERSONALITY
:
10869 ret
= io_unregister_personality(ctx
, nr_args
);
10871 case IORING_REGISTER_ENABLE_RINGS
:
10873 if (arg
|| nr_args
)
10875 ret
= io_register_enable_rings(ctx
);
10877 case IORING_REGISTER_RESTRICTIONS
:
10878 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
10880 case IORING_REGISTER_FILES2
:
10881 ret
= io_register_rsrc(ctx
, arg
, nr_args
, IORING_RSRC_FILE
);
10883 case IORING_REGISTER_FILES_UPDATE2
:
10884 ret
= io_register_rsrc_update(ctx
, arg
, nr_args
,
10887 case IORING_REGISTER_BUFFERS2
:
10888 ret
= io_register_rsrc(ctx
, arg
, nr_args
, IORING_RSRC_BUFFER
);
10890 case IORING_REGISTER_BUFFERS_UPDATE
:
10891 ret
= io_register_rsrc_update(ctx
, arg
, nr_args
,
10892 IORING_RSRC_BUFFER
);
10894 case IORING_REGISTER_IOWQ_AFF
:
10896 if (!arg
|| !nr_args
)
10898 ret
= io_register_iowq_aff(ctx
, arg
, nr_args
);
10900 case IORING_UNREGISTER_IOWQ_AFF
:
10902 if (arg
|| nr_args
)
10904 ret
= io_unregister_iowq_aff(ctx
);
10906 case IORING_REGISTER_IOWQ_MAX_WORKERS
:
10908 if (!arg
|| nr_args
!= 2)
10910 ret
= io_register_iowq_max_workers(ctx
, arg
);
10917 if (io_register_op_must_quiesce(opcode
)) {
10918 /* bring the ctx back to life */
10919 percpu_ref_reinit(&ctx
->refs
);
10920 reinit_completion(&ctx
->ref_comp
);
10925 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
10926 void __user
*, arg
, unsigned int, nr_args
)
10928 struct io_ring_ctx
*ctx
;
10937 if (f
.file
->f_op
!= &io_uring_fops
)
10940 ctx
= f
.file
->private_data
;
10942 io_run_task_work();
10944 mutex_lock(&ctx
->uring_lock
);
10945 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
10946 mutex_unlock(&ctx
->uring_lock
);
10947 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
10948 ctx
->cq_ev_fd
!= NULL
, ret
);
10954 static int __init
io_uring_init(void)
10956 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10957 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10958 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10961 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10962 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10963 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
10964 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
10965 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
10966 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
10967 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
10968 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
10969 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
10970 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
10971 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
10972 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
10973 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
10974 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
10975 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
10976 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
10977 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
10978 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
10979 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
10980 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
10981 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
10982 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
10983 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
10984 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
10985 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
10986 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
10987 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
10988 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
10989 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
10990 BUILD_BUG_SQE_ELEM(40, __u16
, buf_group
);
10991 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
10992 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
10993 BUILD_BUG_SQE_ELEM(44, __u32
, file_index
);
10995 BUILD_BUG_ON(sizeof(struct io_uring_files_update
) !=
10996 sizeof(struct io_uring_rsrc_update
));
10997 BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update
) >
10998 sizeof(struct io_uring_rsrc_update2
));
11000 /* ->buf_index is u16 */
11001 BUILD_BUG_ON(IORING_MAX_REG_BUFFERS
>= (1u << 16));
11003 /* should fit into one byte */
11004 BUILD_BUG_ON(SQE_VALID_FLAGS
>= (1 << 8));
11006 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
11007 BUILD_BUG_ON(__REQ_F_LAST_BIT
> 8 * sizeof(int));
11009 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
|
11013 __initcall(io_uring_init
);