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
;
462 struct io_uring_task
{
463 /* submission side */
466 struct wait_queue_head wait
;
467 const struct io_ring_ctx
*last
;
469 struct percpu_counter inflight
;
470 atomic_t inflight_tracked
;
473 spinlock_t task_lock
;
474 struct io_wq_work_list task_list
;
475 struct callback_head task_work
;
480 * First field must be the file pointer in all the
481 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
483 struct io_poll_iocb
{
485 struct wait_queue_head
*head
;
489 struct wait_queue_entry wait
;
492 struct io_poll_update
{
498 bool update_user_data
;
507 struct io_timeout_data
{
508 struct io_kiocb
*req
;
509 struct hrtimer timer
;
510 struct timespec64 ts
;
511 enum hrtimer_mode mode
;
517 struct sockaddr __user
*addr
;
518 int __user
*addr_len
;
521 unsigned long nofile
;
541 struct list_head list
;
542 /* head of the link, used by linked timeouts only */
543 struct io_kiocb
*head
;
544 /* for linked completions */
545 struct io_kiocb
*prev
;
548 struct io_timeout_rem
{
553 struct timespec64 ts
;
559 /* NOTE: kiocb has the file as the first member, so don't do it here */
567 struct sockaddr __user
*addr
;
574 struct compat_msghdr __user
*umsg_compat
;
575 struct user_msghdr __user
*umsg
;
581 struct io_buffer
*kbuf
;
588 struct filename
*filename
;
590 unsigned long nofile
;
593 struct io_rsrc_update
{
619 struct epoll_event event
;
623 struct file
*file_out
;
624 struct file
*file_in
;
631 struct io_provide_buf
{
645 const char __user
*filename
;
646 struct statx __user
*buffer
;
658 struct filename
*oldpath
;
659 struct filename
*newpath
;
667 struct filename
*filename
;
674 struct filename
*filename
;
680 struct filename
*oldpath
;
681 struct filename
*newpath
;
688 struct filename
*oldpath
;
689 struct filename
*newpath
;
693 struct io_completion
{
698 struct io_async_connect
{
699 struct sockaddr_storage address
;
702 struct io_async_msghdr
{
703 struct iovec fast_iov
[UIO_FASTIOV
];
704 /* points to an allocated iov, if NULL we use fast_iov instead */
705 struct iovec
*free_iov
;
706 struct sockaddr __user
*uaddr
;
708 struct sockaddr_storage addr
;
712 struct iovec fast_iov
[UIO_FASTIOV
];
713 const struct iovec
*free_iovec
;
714 struct iov_iter iter
;
715 struct iov_iter_state iter_state
;
717 struct wait_page_queue wpq
;
721 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
722 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
723 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
724 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
725 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
726 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
728 /* first byte is taken by user flags, shift it to not overlap */
733 REQ_F_LINK_TIMEOUT_BIT
,
734 REQ_F_NEED_CLEANUP_BIT
,
736 REQ_F_BUFFER_SELECTED_BIT
,
737 REQ_F_COMPLETE_INLINE_BIT
,
741 REQ_F_ARM_LTIMEOUT_BIT
,
742 /* keep async read/write and isreg together and in order */
743 REQ_F_NOWAIT_READ_BIT
,
744 REQ_F_NOWAIT_WRITE_BIT
,
747 /* not a real bit, just to check we're not overflowing the space */
753 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
754 /* drain existing IO first */
755 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
757 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
758 /* doesn't sever on completion < 0 */
759 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
761 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
762 /* IOSQE_BUFFER_SELECT */
763 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
765 /* fail rest of links */
766 REQ_F_FAIL
= BIT(REQ_F_FAIL_BIT
),
767 /* on inflight list, should be cancelled and waited on exit reliably */
768 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
769 /* read/write uses file position */
770 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
771 /* must not punt to workers */
772 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
773 /* has or had linked timeout */
774 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
776 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
777 /* already went through poll handler */
778 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
779 /* buffer already selected */
780 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
781 /* completion is deferred through io_comp_state */
782 REQ_F_COMPLETE_INLINE
= BIT(REQ_F_COMPLETE_INLINE_BIT
),
783 /* caller should reissue async */
784 REQ_F_REISSUE
= BIT(REQ_F_REISSUE_BIT
),
785 /* supports async reads */
786 REQ_F_NOWAIT_READ
= BIT(REQ_F_NOWAIT_READ_BIT
),
787 /* supports async writes */
788 REQ_F_NOWAIT_WRITE
= BIT(REQ_F_NOWAIT_WRITE_BIT
),
790 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
791 /* has creds assigned */
792 REQ_F_CREDS
= BIT(REQ_F_CREDS_BIT
),
793 /* skip refcounting if not set */
794 REQ_F_REFCOUNT
= BIT(REQ_F_REFCOUNT_BIT
),
795 /* there is a linked timeout that has to be armed */
796 REQ_F_ARM_LTIMEOUT
= BIT(REQ_F_ARM_LTIMEOUT_BIT
),
800 struct io_poll_iocb poll
;
801 struct io_poll_iocb
*double_poll
;
804 typedef void (*io_req_tw_func_t
)(struct io_kiocb
*req
, bool *locked
);
806 struct io_task_work
{
808 struct io_wq_work_node node
;
809 struct llist_node fallback_node
;
811 io_req_tw_func_t func
;
815 IORING_RSRC_FILE
= 0,
816 IORING_RSRC_BUFFER
= 1,
820 * NOTE! Each of the iocb union members has the file pointer
821 * as the first entry in their struct definition. So you can
822 * access the file pointer through any of the sub-structs,
823 * or directly as just 'ki_filp' in this struct.
829 struct io_poll_iocb poll
;
830 struct io_poll_update poll_update
;
831 struct io_accept accept
;
833 struct io_cancel cancel
;
834 struct io_timeout timeout
;
835 struct io_timeout_rem timeout_rem
;
836 struct io_connect connect
;
837 struct io_sr_msg sr_msg
;
839 struct io_close close
;
840 struct io_rsrc_update rsrc_update
;
841 struct io_fadvise fadvise
;
842 struct io_madvise madvise
;
843 struct io_epoll epoll
;
844 struct io_splice splice
;
845 struct io_provide_buf pbuf
;
846 struct io_statx statx
;
847 struct io_shutdown shutdown
;
848 struct io_rename rename
;
849 struct io_unlink unlink
;
850 struct io_mkdir mkdir
;
851 struct io_symlink symlink
;
852 struct io_hardlink hardlink
;
853 /* use only after cleaning per-op data, see io_clean_op() */
854 struct io_completion
compl;
857 /* opcode allocated if it needs to store data for async defer */
860 /* polled IO has completed */
866 struct io_ring_ctx
*ctx
;
869 struct task_struct
*task
;
872 struct io_kiocb
*link
;
873 struct percpu_ref
*fixed_rsrc_refs
;
875 /* used with ctx->iopoll_list with reads/writes */
876 struct list_head inflight_entry
;
877 struct io_task_work io_task_work
;
878 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
879 struct hlist_node hash_node
;
880 struct async_poll
*apoll
;
881 struct io_wq_work work
;
882 const struct cred
*creds
;
884 /* store used ubuf, so we can prevent reloading */
885 struct io_mapped_ubuf
*imu
;
888 struct io_tctx_node
{
889 struct list_head ctx_node
;
890 struct task_struct
*task
;
891 struct io_ring_ctx
*ctx
;
894 struct io_defer_entry
{
895 struct list_head list
;
896 struct io_kiocb
*req
;
901 /* needs req->file assigned */
902 unsigned needs_file
: 1;
903 /* hash wq insertion if file is a regular file */
904 unsigned hash_reg_file
: 1;
905 /* unbound wq insertion if file is a non-regular file */
906 unsigned unbound_nonreg_file
: 1;
907 /* opcode is not supported by this kernel */
908 unsigned not_supported
: 1;
909 /* set if opcode supports polled "wait" */
911 unsigned pollout
: 1;
912 /* op supports buffer selection */
913 unsigned buffer_select
: 1;
914 /* do prep async if is going to be punted */
915 unsigned needs_async_setup
: 1;
916 /* should block plug */
918 /* size of async data needed, if any */
919 unsigned short async_size
;
922 static const struct io_op_def io_op_defs
[] = {
923 [IORING_OP_NOP
] = {},
924 [IORING_OP_READV
] = {
926 .unbound_nonreg_file
= 1,
929 .needs_async_setup
= 1,
931 .async_size
= sizeof(struct io_async_rw
),
933 [IORING_OP_WRITEV
] = {
936 .unbound_nonreg_file
= 1,
938 .needs_async_setup
= 1,
940 .async_size
= sizeof(struct io_async_rw
),
942 [IORING_OP_FSYNC
] = {
945 [IORING_OP_READ_FIXED
] = {
947 .unbound_nonreg_file
= 1,
950 .async_size
= sizeof(struct io_async_rw
),
952 [IORING_OP_WRITE_FIXED
] = {
955 .unbound_nonreg_file
= 1,
958 .async_size
= sizeof(struct io_async_rw
),
960 [IORING_OP_POLL_ADD
] = {
962 .unbound_nonreg_file
= 1,
964 [IORING_OP_POLL_REMOVE
] = {},
965 [IORING_OP_SYNC_FILE_RANGE
] = {
968 [IORING_OP_SENDMSG
] = {
970 .unbound_nonreg_file
= 1,
972 .needs_async_setup
= 1,
973 .async_size
= sizeof(struct io_async_msghdr
),
975 [IORING_OP_RECVMSG
] = {
977 .unbound_nonreg_file
= 1,
980 .needs_async_setup
= 1,
981 .async_size
= sizeof(struct io_async_msghdr
),
983 [IORING_OP_TIMEOUT
] = {
984 .async_size
= sizeof(struct io_timeout_data
),
986 [IORING_OP_TIMEOUT_REMOVE
] = {
987 /* used by timeout updates' prep() */
989 [IORING_OP_ACCEPT
] = {
991 .unbound_nonreg_file
= 1,
994 [IORING_OP_ASYNC_CANCEL
] = {},
995 [IORING_OP_LINK_TIMEOUT
] = {
996 .async_size
= sizeof(struct io_timeout_data
),
998 [IORING_OP_CONNECT
] = {
1000 .unbound_nonreg_file
= 1,
1002 .needs_async_setup
= 1,
1003 .async_size
= sizeof(struct io_async_connect
),
1005 [IORING_OP_FALLOCATE
] = {
1008 [IORING_OP_OPENAT
] = {},
1009 [IORING_OP_CLOSE
] = {},
1010 [IORING_OP_FILES_UPDATE
] = {},
1011 [IORING_OP_STATX
] = {},
1012 [IORING_OP_READ
] = {
1014 .unbound_nonreg_file
= 1,
1018 .async_size
= sizeof(struct io_async_rw
),
1020 [IORING_OP_WRITE
] = {
1023 .unbound_nonreg_file
= 1,
1026 .async_size
= sizeof(struct io_async_rw
),
1028 [IORING_OP_FADVISE
] = {
1031 [IORING_OP_MADVISE
] = {},
1032 [IORING_OP_SEND
] = {
1034 .unbound_nonreg_file
= 1,
1037 [IORING_OP_RECV
] = {
1039 .unbound_nonreg_file
= 1,
1043 [IORING_OP_OPENAT2
] = {
1045 [IORING_OP_EPOLL_CTL
] = {
1046 .unbound_nonreg_file
= 1,
1048 [IORING_OP_SPLICE
] = {
1051 .unbound_nonreg_file
= 1,
1053 [IORING_OP_PROVIDE_BUFFERS
] = {},
1054 [IORING_OP_REMOVE_BUFFERS
] = {},
1058 .unbound_nonreg_file
= 1,
1060 [IORING_OP_SHUTDOWN
] = {
1063 [IORING_OP_RENAMEAT
] = {},
1064 [IORING_OP_UNLINKAT
] = {},
1065 [IORING_OP_MKDIRAT
] = {},
1066 [IORING_OP_SYMLINKAT
] = {},
1067 [IORING_OP_LINKAT
] = {},
1070 /* requests with any of those set should undergo io_disarm_next() */
1071 #define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
1073 static bool io_disarm_next(struct io_kiocb
*req
);
1074 static void io_uring_del_tctx_node(unsigned long index
);
1075 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
1076 struct task_struct
*task
,
1078 static void io_uring_cancel_generic(bool cancel_all
, struct io_sq_data
*sqd
);
1080 static bool io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1081 long res
, unsigned int cflags
);
1082 static void io_put_req(struct io_kiocb
*req
);
1083 static void io_put_req_deferred(struct io_kiocb
*req
);
1084 static void io_dismantle_req(struct io_kiocb
*req
);
1085 static void io_queue_linked_timeout(struct io_kiocb
*req
);
1086 static int __io_register_rsrc_update(struct io_ring_ctx
*ctx
, unsigned type
,
1087 struct io_uring_rsrc_update2
*up
,
1089 static void io_clean_op(struct io_kiocb
*req
);
1090 static struct file
*io_file_get(struct io_ring_ctx
*ctx
,
1091 struct io_kiocb
*req
, int fd
, bool fixed
);
1092 static void __io_queue_sqe(struct io_kiocb
*req
);
1093 static void io_rsrc_put_work(struct work_struct
*work
);
1095 static void io_req_task_queue(struct io_kiocb
*req
);
1096 static void io_submit_flush_completions(struct io_ring_ctx
*ctx
);
1097 static int io_req_prep_async(struct io_kiocb
*req
);
1099 static int io_install_fixed_file(struct io_kiocb
*req
, struct file
*file
,
1100 unsigned int issue_flags
, u32 slot_index
);
1101 static int io_close_fixed(struct io_kiocb
*req
, unsigned int issue_flags
);
1103 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
);
1105 static struct kmem_cache
*req_cachep
;
1107 static const struct file_operations io_uring_fops
;
1109 struct sock
*io_uring_get_socket(struct file
*file
)
1111 #if defined(CONFIG_UNIX)
1112 if (file
->f_op
== &io_uring_fops
) {
1113 struct io_ring_ctx
*ctx
= file
->private_data
;
1115 return ctx
->ring_sock
->sk
;
1120 EXPORT_SYMBOL(io_uring_get_socket
);
1122 static inline void io_tw_lock(struct io_ring_ctx
*ctx
, bool *locked
)
1125 mutex_lock(&ctx
->uring_lock
);
1130 #define io_for_each_link(pos, head) \
1131 for (pos = (head); pos; pos = pos->link)
1134 * Shamelessly stolen from the mm implementation of page reference checking,
1135 * see commit f958d7b528b1 for details.
1137 #define req_ref_zero_or_close_to_overflow(req) \
1138 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1140 static inline bool req_ref_inc_not_zero(struct io_kiocb
*req
)
1142 WARN_ON_ONCE(!(req
->flags
& REQ_F_REFCOUNT
));
1143 return atomic_inc_not_zero(&req
->refs
);
1146 static inline bool req_ref_put_and_test(struct io_kiocb
*req
)
1148 if (likely(!(req
->flags
& REQ_F_REFCOUNT
)))
1151 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1152 return atomic_dec_and_test(&req
->refs
);
1155 static inline void req_ref_put(struct io_kiocb
*req
)
1157 WARN_ON_ONCE(!(req
->flags
& REQ_F_REFCOUNT
));
1158 WARN_ON_ONCE(req_ref_put_and_test(req
));
1161 static inline void req_ref_get(struct io_kiocb
*req
)
1163 WARN_ON_ONCE(!(req
->flags
& REQ_F_REFCOUNT
));
1164 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req
));
1165 atomic_inc(&req
->refs
);
1168 static inline void __io_req_set_refcount(struct io_kiocb
*req
, int nr
)
1170 if (!(req
->flags
& REQ_F_REFCOUNT
)) {
1171 req
->flags
|= REQ_F_REFCOUNT
;
1172 atomic_set(&req
->refs
, nr
);
1176 static inline void io_req_set_refcount(struct io_kiocb
*req
)
1178 __io_req_set_refcount(req
, 1);
1181 static inline void io_req_set_rsrc_node(struct io_kiocb
*req
)
1183 struct io_ring_ctx
*ctx
= req
->ctx
;
1185 if (!req
->fixed_rsrc_refs
) {
1186 req
->fixed_rsrc_refs
= &ctx
->rsrc_node
->refs
;
1187 percpu_ref_get(req
->fixed_rsrc_refs
);
1191 static void io_refs_resurrect(struct percpu_ref
*ref
, struct completion
*compl)
1193 bool got
= percpu_ref_tryget(ref
);
1195 /* already at zero, wait for ->release() */
1197 wait_for_completion(compl);
1198 percpu_ref_resurrect(ref
);
1200 percpu_ref_put(ref
);
1203 static bool io_match_task(struct io_kiocb
*head
, struct task_struct
*task
,
1206 struct io_kiocb
*req
;
1208 if (task
&& head
->task
!= task
)
1213 io_for_each_link(req
, head
) {
1214 if (req
->flags
& REQ_F_INFLIGHT
)
1220 static inline void req_set_fail(struct io_kiocb
*req
)
1222 req
->flags
|= REQ_F_FAIL
;
1225 static inline void req_fail_link_node(struct io_kiocb
*req
, int res
)
1231 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1233 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1235 complete(&ctx
->ref_comp
);
1238 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1240 return !req
->timeout
.off
;
1243 static void io_fallback_req_func(struct work_struct
*work
)
1245 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
1246 fallback_work
.work
);
1247 struct llist_node
*node
= llist_del_all(&ctx
->fallback_llist
);
1248 struct io_kiocb
*req
, *tmp
;
1249 bool locked
= false;
1251 percpu_ref_get(&ctx
->refs
);
1252 llist_for_each_entry_safe(req
, tmp
, node
, io_task_work
.fallback_node
)
1253 req
->io_task_work
.func(req
, &locked
);
1256 if (ctx
->submit_state
.compl_nr
)
1257 io_submit_flush_completions(ctx
);
1258 mutex_unlock(&ctx
->uring_lock
);
1260 percpu_ref_put(&ctx
->refs
);
1264 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1266 struct io_ring_ctx
*ctx
;
1269 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1274 * Use 5 bits less than the max cq entries, that should give us around
1275 * 32 entries per hash list if totally full and uniformly spread.
1277 hash_bits
= ilog2(p
->cq_entries
);
1281 ctx
->cancel_hash_bits
= hash_bits
;
1282 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1284 if (!ctx
->cancel_hash
)
1286 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1288 ctx
->dummy_ubuf
= kzalloc(sizeof(*ctx
->dummy_ubuf
), GFP_KERNEL
);
1289 if (!ctx
->dummy_ubuf
)
1291 /* set invalid range, so io_import_fixed() fails meeting it */
1292 ctx
->dummy_ubuf
->ubuf
= -1UL;
1294 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1295 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1298 ctx
->flags
= p
->flags
;
1299 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1300 INIT_LIST_HEAD(&ctx
->sqd_list
);
1301 init_waitqueue_head(&ctx
->poll_wait
);
1302 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1303 init_completion(&ctx
->ref_comp
);
1304 xa_init_flags(&ctx
->io_buffers
, XA_FLAGS_ALLOC1
);
1305 xa_init_flags(&ctx
->personalities
, XA_FLAGS_ALLOC1
);
1306 mutex_init(&ctx
->uring_lock
);
1307 init_waitqueue_head(&ctx
->cq_wait
);
1308 spin_lock_init(&ctx
->completion_lock
);
1309 spin_lock_init(&ctx
->timeout_lock
);
1310 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1311 INIT_LIST_HEAD(&ctx
->defer_list
);
1312 INIT_LIST_HEAD(&ctx
->timeout_list
);
1313 INIT_LIST_HEAD(&ctx
->ltimeout_list
);
1314 spin_lock_init(&ctx
->rsrc_ref_lock
);
1315 INIT_LIST_HEAD(&ctx
->rsrc_ref_list
);
1316 INIT_DELAYED_WORK(&ctx
->rsrc_put_work
, io_rsrc_put_work
);
1317 init_llist_head(&ctx
->rsrc_put_llist
);
1318 INIT_LIST_HEAD(&ctx
->tctx_list
);
1319 INIT_LIST_HEAD(&ctx
->submit_state
.free_list
);
1320 INIT_LIST_HEAD(&ctx
->locked_free_list
);
1321 INIT_DELAYED_WORK(&ctx
->fallback_work
, io_fallback_req_func
);
1324 kfree(ctx
->dummy_ubuf
);
1325 kfree(ctx
->cancel_hash
);
1330 static void io_account_cq_overflow(struct io_ring_ctx
*ctx
)
1332 struct io_rings
*r
= ctx
->rings
;
1334 WRITE_ONCE(r
->cq_overflow
, READ_ONCE(r
->cq_overflow
) + 1);
1338 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1340 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1341 struct io_ring_ctx
*ctx
= req
->ctx
;
1343 return seq
+ READ_ONCE(ctx
->cq_extra
) != ctx
->cached_cq_tail
;
1349 #define FFS_ASYNC_READ 0x1UL
1350 #define FFS_ASYNC_WRITE 0x2UL
1352 #define FFS_ISREG 0x4UL
1354 #define FFS_ISREG 0x0UL
1356 #define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
1358 static inline bool io_req_ffs_set(struct io_kiocb
*req
)
1360 return IS_ENABLED(CONFIG_64BIT
) && (req
->flags
& REQ_F_FIXED_FILE
);
1363 static void io_req_track_inflight(struct io_kiocb
*req
)
1365 if (!(req
->flags
& REQ_F_INFLIGHT
)) {
1366 req
->flags
|= REQ_F_INFLIGHT
;
1367 atomic_inc(¤t
->io_uring
->inflight_tracked
);
1371 static inline void io_unprep_linked_timeout(struct io_kiocb
*req
)
1373 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1376 static struct io_kiocb
*__io_prep_linked_timeout(struct io_kiocb
*req
)
1378 if (WARN_ON_ONCE(!req
->link
))
1381 req
->flags
&= ~REQ_F_ARM_LTIMEOUT
;
1382 req
->flags
|= REQ_F_LINK_TIMEOUT
;
1384 /* linked timeouts should have two refs once prep'ed */
1385 io_req_set_refcount(req
);
1386 __io_req_set_refcount(req
->link
, 2);
1390 static inline struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
1392 if (likely(!(req
->flags
& REQ_F_ARM_LTIMEOUT
)))
1394 return __io_prep_linked_timeout(req
);
1397 static void io_prep_async_work(struct io_kiocb
*req
)
1399 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1400 struct io_ring_ctx
*ctx
= req
->ctx
;
1402 if (!(req
->flags
& REQ_F_CREDS
)) {
1403 req
->flags
|= REQ_F_CREDS
;
1404 req
->creds
= get_current_cred();
1407 req
->work
.list
.next
= NULL
;
1408 req
->work
.flags
= 0;
1409 if (req
->flags
& REQ_F_FORCE_ASYNC
)
1410 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
1412 if (req
->flags
& REQ_F_ISREG
) {
1413 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1414 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1415 } else if (!req
->file
|| !S_ISBLK(file_inode(req
->file
)->i_mode
)) {
1416 if (def
->unbound_nonreg_file
)
1417 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1420 switch (req
->opcode
) {
1421 case IORING_OP_SPLICE
:
1423 if (!S_ISREG(file_inode(req
->splice
.file_in
)->i_mode
))
1424 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1429 static void io_prep_async_link(struct io_kiocb
*req
)
1431 struct io_kiocb
*cur
;
1433 if (req
->flags
& REQ_F_LINK_TIMEOUT
) {
1434 struct io_ring_ctx
*ctx
= req
->ctx
;
1436 spin_lock(&ctx
->completion_lock
);
1437 io_for_each_link(cur
, req
)
1438 io_prep_async_work(cur
);
1439 spin_unlock(&ctx
->completion_lock
);
1441 io_for_each_link(cur
, req
)
1442 io_prep_async_work(cur
);
1446 static void io_queue_async_work(struct io_kiocb
*req
, bool *locked
)
1448 struct io_ring_ctx
*ctx
= req
->ctx
;
1449 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1450 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1452 /* must not take the lock, NULL it as a precaution */
1456 BUG_ON(!tctx
->io_wq
);
1458 /* init ->work of the whole link before punting */
1459 io_prep_async_link(req
);
1462 * Not expected to happen, but if we do have a bug where this _can_
1463 * happen, catch it here and ensure the request is marked as
1464 * canceled. That will make io-wq go through the usual work cancel
1465 * procedure rather than attempt to run this request (or create a new
1468 if (WARN_ON_ONCE(!same_thread_group(req
->task
, current
)))
1469 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1471 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1472 &req
->work
, req
->flags
);
1473 io_wq_enqueue(tctx
->io_wq
, &req
->work
);
1475 io_queue_linked_timeout(link
);
1478 static void io_kill_timeout(struct io_kiocb
*req
, int status
)
1479 __must_hold(&req
->ctx
->completion_lock
)
1480 __must_hold(&req
->ctx
->timeout_lock
)
1482 struct io_timeout_data
*io
= req
->async_data
;
1484 if (hrtimer_try_to_cancel(&io
->timer
) != -1) {
1487 atomic_set(&req
->ctx
->cq_timeouts
,
1488 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1489 list_del_init(&req
->timeout
.list
);
1490 io_cqring_fill_event(req
->ctx
, req
->user_data
, status
, 0);
1491 io_put_req_deferred(req
);
1495 static void io_queue_deferred(struct io_ring_ctx
*ctx
)
1497 while (!list_empty(&ctx
->defer_list
)) {
1498 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1499 struct io_defer_entry
, list
);
1501 if (req_need_defer(de
->req
, de
->seq
))
1503 list_del_init(&de
->list
);
1504 io_req_task_queue(de
->req
);
1509 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1510 __must_hold(&ctx
->completion_lock
)
1512 u32 seq
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
1514 spin_lock_irq(&ctx
->timeout_lock
);
1515 while (!list_empty(&ctx
->timeout_list
)) {
1516 u32 events_needed
, events_got
;
1517 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1518 struct io_kiocb
, timeout
.list
);
1520 if (io_is_timeout_noseq(req
))
1524 * Since seq can easily wrap around over time, subtract
1525 * the last seq at which timeouts were flushed before comparing.
1526 * Assuming not more than 2^31-1 events have happened since,
1527 * these subtractions won't have wrapped, so we can check if
1528 * target is in [last_seq, current_seq] by comparing the two.
1530 events_needed
= req
->timeout
.target_seq
- ctx
->cq_last_tm_flush
;
1531 events_got
= seq
- ctx
->cq_last_tm_flush
;
1532 if (events_got
< events_needed
)
1535 list_del_init(&req
->timeout
.list
);
1536 io_kill_timeout(req
, 0);
1538 ctx
->cq_last_tm_flush
= seq
;
1539 spin_unlock_irq(&ctx
->timeout_lock
);
1542 static void __io_commit_cqring_flush(struct io_ring_ctx
*ctx
)
1544 if (ctx
->off_timeout_used
)
1545 io_flush_timeouts(ctx
);
1546 if (ctx
->drain_active
)
1547 io_queue_deferred(ctx
);
1550 static inline void io_commit_cqring(struct io_ring_ctx
*ctx
)
1552 if (unlikely(ctx
->off_timeout_used
|| ctx
->drain_active
))
1553 __io_commit_cqring_flush(ctx
);
1554 /* order cqe stores with ring update */
1555 smp_store_release(&ctx
->rings
->cq
.tail
, ctx
->cached_cq_tail
);
1558 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1560 struct io_rings
*r
= ctx
->rings
;
1562 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== ctx
->sq_entries
;
1565 static inline unsigned int __io_cqring_events(struct io_ring_ctx
*ctx
)
1567 return ctx
->cached_cq_tail
- READ_ONCE(ctx
->rings
->cq
.head
);
1570 static inline struct io_uring_cqe
*io_get_cqe(struct io_ring_ctx
*ctx
)
1572 struct io_rings
*rings
= ctx
->rings
;
1573 unsigned tail
, mask
= ctx
->cq_entries
- 1;
1576 * writes to the cq entry need to come after reading head; the
1577 * control dependency is enough as we're using WRITE_ONCE to
1580 if (__io_cqring_events(ctx
) == ctx
->cq_entries
)
1583 tail
= ctx
->cached_cq_tail
++;
1584 return &rings
->cqes
[tail
& mask
];
1587 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1589 if (likely(!ctx
->cq_ev_fd
))
1591 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1593 return !ctx
->eventfd_async
|| io_wq_current_is_worker();
1597 * This should only get called when at least one event has been posted.
1598 * Some applications rely on the eventfd notification count only changing
1599 * IFF a new CQE has been added to the CQ ring. There's no depedency on
1600 * 1:1 relationship between how many times this function is called (and
1601 * hence the eventfd count) and number of CQEs posted to the CQ ring.
1603 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1606 * wake_up_all() may seem excessive, but io_wake_function() and
1607 * io_should_wake() handle the termination of the loop and only
1608 * wake as many waiters as we need to.
1610 if (wq_has_sleeper(&ctx
->cq_wait
))
1611 wake_up_all(&ctx
->cq_wait
);
1612 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1613 wake_up(&ctx
->sq_data
->wait
);
1614 if (io_should_trigger_evfd(ctx
))
1615 eventfd_signal(ctx
->cq_ev_fd
, 1);
1616 if (waitqueue_active(&ctx
->poll_wait
))
1617 wake_up_interruptible(&ctx
->poll_wait
);
1620 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx
*ctx
)
1622 /* see waitqueue_active() comment */
1625 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1626 if (waitqueue_active(&ctx
->cq_wait
))
1627 wake_up_all(&ctx
->cq_wait
);
1629 if (io_should_trigger_evfd(ctx
))
1630 eventfd_signal(ctx
->cq_ev_fd
, 1);
1631 if (waitqueue_active(&ctx
->poll_wait
))
1632 wake_up_interruptible(&ctx
->poll_wait
);
1635 /* Returns true if there are no backlogged entries after the flush */
1636 static bool __io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1638 bool all_flushed
, posted
;
1640 if (!force
&& __io_cqring_events(ctx
) == ctx
->cq_entries
)
1644 spin_lock(&ctx
->completion_lock
);
1645 while (!list_empty(&ctx
->cq_overflow_list
)) {
1646 struct io_uring_cqe
*cqe
= io_get_cqe(ctx
);
1647 struct io_overflow_cqe
*ocqe
;
1651 ocqe
= list_first_entry(&ctx
->cq_overflow_list
,
1652 struct io_overflow_cqe
, list
);
1654 memcpy(cqe
, &ocqe
->cqe
, sizeof(*cqe
));
1656 io_account_cq_overflow(ctx
);
1659 list_del(&ocqe
->list
);
1663 all_flushed
= list_empty(&ctx
->cq_overflow_list
);
1665 clear_bit(0, &ctx
->check_cq_overflow
);
1666 WRITE_ONCE(ctx
->rings
->sq_flags
,
1667 ctx
->rings
->sq_flags
& ~IORING_SQ_CQ_OVERFLOW
);
1671 io_commit_cqring(ctx
);
1672 spin_unlock(&ctx
->completion_lock
);
1674 io_cqring_ev_posted(ctx
);
1678 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
)
1682 if (test_bit(0, &ctx
->check_cq_overflow
)) {
1683 /* iopoll syncs against uring_lock, not completion_lock */
1684 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1685 mutex_lock(&ctx
->uring_lock
);
1686 ret
= __io_cqring_overflow_flush(ctx
, false);
1687 if (ctx
->flags
& IORING_SETUP_IOPOLL
)
1688 mutex_unlock(&ctx
->uring_lock
);
1694 /* must to be called somewhat shortly after putting a request */
1695 static inline void io_put_task(struct task_struct
*task
, int nr
)
1697 struct io_uring_task
*tctx
= task
->io_uring
;
1699 if (likely(task
== current
)) {
1700 tctx
->cached_refs
+= nr
;
1702 percpu_counter_sub(&tctx
->inflight
, nr
);
1703 if (unlikely(atomic_read(&tctx
->in_idle
)))
1704 wake_up(&tctx
->wait
);
1705 put_task_struct_many(task
, nr
);
1709 static void io_task_refs_refill(struct io_uring_task
*tctx
)
1711 unsigned int refill
= -tctx
->cached_refs
+ IO_TCTX_REFS_CACHE_NR
;
1713 percpu_counter_add(&tctx
->inflight
, refill
);
1714 refcount_add(refill
, ¤t
->usage
);
1715 tctx
->cached_refs
+= refill
;
1718 static inline void io_get_task_refs(int nr
)
1720 struct io_uring_task
*tctx
= current
->io_uring
;
1722 tctx
->cached_refs
-= nr
;
1723 if (unlikely(tctx
->cached_refs
< 0))
1724 io_task_refs_refill(tctx
);
1727 static bool io_cqring_event_overflow(struct io_ring_ctx
*ctx
, u64 user_data
,
1728 long res
, unsigned int cflags
)
1730 struct io_overflow_cqe
*ocqe
;
1732 ocqe
= kmalloc(sizeof(*ocqe
), GFP_ATOMIC
| __GFP_ACCOUNT
);
1735 * If we're in ring overflow flush mode, or in task cancel mode,
1736 * or cannot allocate an overflow entry, then we need to drop it
1739 io_account_cq_overflow(ctx
);
1742 if (list_empty(&ctx
->cq_overflow_list
)) {
1743 set_bit(0, &ctx
->check_cq_overflow
);
1744 WRITE_ONCE(ctx
->rings
->sq_flags
,
1745 ctx
->rings
->sq_flags
| IORING_SQ_CQ_OVERFLOW
);
1748 ocqe
->cqe
.user_data
= user_data
;
1749 ocqe
->cqe
.res
= res
;
1750 ocqe
->cqe
.flags
= cflags
;
1751 list_add_tail(&ocqe
->list
, &ctx
->cq_overflow_list
);
1755 static inline bool __io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1756 long res
, unsigned int cflags
)
1758 struct io_uring_cqe
*cqe
;
1760 trace_io_uring_complete(ctx
, user_data
, res
, cflags
);
1763 * If we can't get a cq entry, userspace overflowed the
1764 * submission (by quite a lot). Increment the overflow count in
1767 cqe
= io_get_cqe(ctx
);
1769 WRITE_ONCE(cqe
->user_data
, user_data
);
1770 WRITE_ONCE(cqe
->res
, res
);
1771 WRITE_ONCE(cqe
->flags
, cflags
);
1774 return io_cqring_event_overflow(ctx
, user_data
, res
, cflags
);
1777 /* not as hot to bloat with inlining */
1778 static noinline
bool io_cqring_fill_event(struct io_ring_ctx
*ctx
, u64 user_data
,
1779 long res
, unsigned int cflags
)
1781 return __io_cqring_fill_event(ctx
, user_data
, res
, cflags
);
1784 static void io_req_complete_post(struct io_kiocb
*req
, long res
,
1785 unsigned int cflags
)
1787 struct io_ring_ctx
*ctx
= req
->ctx
;
1789 spin_lock(&ctx
->completion_lock
);
1790 __io_cqring_fill_event(ctx
, req
->user_data
, res
, cflags
);
1792 * If we're the last reference to this request, add to our locked
1795 if (req_ref_put_and_test(req
)) {
1796 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
1797 if (req
->flags
& IO_DISARM_MASK
)
1798 io_disarm_next(req
);
1800 io_req_task_queue(req
->link
);
1804 io_dismantle_req(req
);
1805 io_put_task(req
->task
, 1);
1806 list_add(&req
->inflight_entry
, &ctx
->locked_free_list
);
1807 ctx
->locked_free_nr
++;
1809 if (!percpu_ref_tryget(&ctx
->refs
))
1812 io_commit_cqring(ctx
);
1813 spin_unlock(&ctx
->completion_lock
);
1816 io_cqring_ev_posted(ctx
);
1817 percpu_ref_put(&ctx
->refs
);
1821 static inline bool io_req_needs_clean(struct io_kiocb
*req
)
1823 return req
->flags
& IO_REQ_CLEAN_FLAGS
;
1826 static void io_req_complete_state(struct io_kiocb
*req
, long res
,
1827 unsigned int cflags
)
1829 if (io_req_needs_clean(req
))
1832 req
->compl.cflags
= cflags
;
1833 req
->flags
|= REQ_F_COMPLETE_INLINE
;
1836 static inline void __io_req_complete(struct io_kiocb
*req
, unsigned issue_flags
,
1837 long res
, unsigned cflags
)
1839 if (issue_flags
& IO_URING_F_COMPLETE_DEFER
)
1840 io_req_complete_state(req
, res
, cflags
);
1842 io_req_complete_post(req
, res
, cflags
);
1845 static inline void io_req_complete(struct io_kiocb
*req
, long res
)
1847 __io_req_complete(req
, 0, res
, 0);
1850 static void io_req_complete_failed(struct io_kiocb
*req
, long res
)
1853 io_req_complete_post(req
, res
, 0);
1856 static void io_req_complete_fail_submit(struct io_kiocb
*req
)
1859 * We don't submit, fail them all, for that replace hardlinks with
1860 * normal links. Extra REQ_F_LINK is tolerated.
1862 req
->flags
&= ~REQ_F_HARDLINK
;
1863 req
->flags
|= REQ_F_LINK
;
1864 io_req_complete_failed(req
, req
->result
);
1868 * Don't initialise the fields below on every allocation, but do that in
1869 * advance and keep them valid across allocations.
1871 static void io_preinit_req(struct io_kiocb
*req
, struct io_ring_ctx
*ctx
)
1875 req
->async_data
= NULL
;
1876 /* not necessary, but safer to zero */
1880 static void io_flush_cached_locked_reqs(struct io_ring_ctx
*ctx
,
1881 struct io_submit_state
*state
)
1883 spin_lock(&ctx
->completion_lock
);
1884 list_splice_init(&ctx
->locked_free_list
, &state
->free_list
);
1885 ctx
->locked_free_nr
= 0;
1886 spin_unlock(&ctx
->completion_lock
);
1889 /* Returns true IFF there are requests in the cache */
1890 static bool io_flush_cached_reqs(struct io_ring_ctx
*ctx
)
1892 struct io_submit_state
*state
= &ctx
->submit_state
;
1896 * If we have more than a batch's worth of requests in our IRQ side
1897 * locked cache, grab the lock and move them over to our submission
1900 if (READ_ONCE(ctx
->locked_free_nr
) > IO_COMPL_BATCH
)
1901 io_flush_cached_locked_reqs(ctx
, state
);
1903 nr
= state
->free_reqs
;
1904 while (!list_empty(&state
->free_list
)) {
1905 struct io_kiocb
*req
= list_first_entry(&state
->free_list
,
1906 struct io_kiocb
, inflight_entry
);
1908 list_del(&req
->inflight_entry
);
1909 state
->reqs
[nr
++] = req
;
1910 if (nr
== ARRAY_SIZE(state
->reqs
))
1914 state
->free_reqs
= nr
;
1919 * A request might get retired back into the request caches even before opcode
1920 * handlers and io_issue_sqe() are done with it, e.g. inline completion path.
1921 * Because of that, io_alloc_req() should be called only under ->uring_lock
1922 * and with extra caution to not get a request that is still worked on.
1924 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
)
1925 __must_hold(&ctx
->uring_lock
)
1927 struct io_submit_state
*state
= &ctx
->submit_state
;
1928 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1931 BUILD_BUG_ON(ARRAY_SIZE(state
->reqs
) < IO_REQ_ALLOC_BATCH
);
1933 if (likely(state
->free_reqs
|| io_flush_cached_reqs(ctx
)))
1936 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, IO_REQ_ALLOC_BATCH
,
1940 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1941 * retry single alloc to be on the safe side.
1943 if (unlikely(ret
<= 0)) {
1944 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1945 if (!state
->reqs
[0])
1950 for (i
= 0; i
< ret
; i
++)
1951 io_preinit_req(state
->reqs
[i
], ctx
);
1952 state
->free_reqs
= ret
;
1955 return state
->reqs
[state
->free_reqs
];
1958 static inline void io_put_file(struct file
*file
)
1964 static void io_dismantle_req(struct io_kiocb
*req
)
1966 unsigned int flags
= req
->flags
;
1968 if (io_req_needs_clean(req
))
1970 if (!(flags
& REQ_F_FIXED_FILE
))
1971 io_put_file(req
->file
);
1972 if (req
->fixed_rsrc_refs
)
1973 percpu_ref_put(req
->fixed_rsrc_refs
);
1974 if (req
->async_data
) {
1975 kfree(req
->async_data
);
1976 req
->async_data
= NULL
;
1980 static void __io_free_req(struct io_kiocb
*req
)
1982 struct io_ring_ctx
*ctx
= req
->ctx
;
1984 io_dismantle_req(req
);
1985 io_put_task(req
->task
, 1);
1987 spin_lock(&ctx
->completion_lock
);
1988 list_add(&req
->inflight_entry
, &ctx
->locked_free_list
);
1989 ctx
->locked_free_nr
++;
1990 spin_unlock(&ctx
->completion_lock
);
1992 percpu_ref_put(&ctx
->refs
);
1995 static inline void io_remove_next_linked(struct io_kiocb
*req
)
1997 struct io_kiocb
*nxt
= req
->link
;
1999 req
->link
= nxt
->link
;
2003 static bool io_kill_linked_timeout(struct io_kiocb
*req
)
2004 __must_hold(&req
->ctx
->completion_lock
)
2005 __must_hold(&req
->ctx
->timeout_lock
)
2007 struct io_kiocb
*link
= req
->link
;
2009 if (link
&& link
->opcode
== IORING_OP_LINK_TIMEOUT
) {
2010 struct io_timeout_data
*io
= link
->async_data
;
2012 io_remove_next_linked(req
);
2013 link
->timeout
.head
= NULL
;
2014 if (hrtimer_try_to_cancel(&io
->timer
) != -1) {
2015 list_del(&link
->timeout
.list
);
2016 io_cqring_fill_event(link
->ctx
, link
->user_data
,
2018 io_put_req_deferred(link
);
2025 static void io_fail_links(struct io_kiocb
*req
)
2026 __must_hold(&req
->ctx
->completion_lock
)
2028 struct io_kiocb
*nxt
, *link
= req
->link
;
2032 long res
= -ECANCELED
;
2034 if (link
->flags
& REQ_F_FAIL
)
2040 trace_io_uring_fail_link(req
, link
);
2041 io_cqring_fill_event(link
->ctx
, link
->user_data
, res
, 0);
2042 io_put_req_deferred(link
);
2047 static bool io_disarm_next(struct io_kiocb
*req
)
2048 __must_hold(&req
->ctx
->completion_lock
)
2050 bool posted
= false;
2052 if (req
->flags
& REQ_F_ARM_LTIMEOUT
) {
2053 struct io_kiocb
*link
= req
->link
;
2055 req
->flags
&= ~REQ_F_ARM_LTIMEOUT
;
2056 if (link
&& link
->opcode
== IORING_OP_LINK_TIMEOUT
) {
2057 io_remove_next_linked(req
);
2058 io_cqring_fill_event(link
->ctx
, link
->user_data
,
2060 io_put_req_deferred(link
);
2063 } else if (req
->flags
& REQ_F_LINK_TIMEOUT
) {
2064 struct io_ring_ctx
*ctx
= req
->ctx
;
2066 spin_lock_irq(&ctx
->timeout_lock
);
2067 posted
= io_kill_linked_timeout(req
);
2068 spin_unlock_irq(&ctx
->timeout_lock
);
2070 if (unlikely((req
->flags
& REQ_F_FAIL
) &&
2071 !(req
->flags
& REQ_F_HARDLINK
))) {
2072 posted
|= (req
->link
!= NULL
);
2078 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
2080 struct io_kiocb
*nxt
;
2083 * If LINK is set, we have dependent requests in this chain. If we
2084 * didn't fail this request, queue the first one up, moving any other
2085 * dependencies to the next request. In case of failure, fail the rest
2088 if (req
->flags
& IO_DISARM_MASK
) {
2089 struct io_ring_ctx
*ctx
= req
->ctx
;
2092 spin_lock(&ctx
->completion_lock
);
2093 posted
= io_disarm_next(req
);
2095 io_commit_cqring(req
->ctx
);
2096 spin_unlock(&ctx
->completion_lock
);
2098 io_cqring_ev_posted(ctx
);
2105 static inline struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
2107 if (likely(!(req
->flags
& (REQ_F_LINK
|REQ_F_HARDLINK
))))
2109 return __io_req_find_next(req
);
2112 static void ctx_flush_and_put(struct io_ring_ctx
*ctx
, bool *locked
)
2117 if (ctx
->submit_state
.compl_nr
)
2118 io_submit_flush_completions(ctx
);
2119 mutex_unlock(&ctx
->uring_lock
);
2122 percpu_ref_put(&ctx
->refs
);
2125 static void tctx_task_work(struct callback_head
*cb
)
2127 bool locked
= false;
2128 struct io_ring_ctx
*ctx
= NULL
;
2129 struct io_uring_task
*tctx
= container_of(cb
, struct io_uring_task
,
2133 struct io_wq_work_node
*node
;
2135 if (!tctx
->task_list
.first
&& locked
&& ctx
->submit_state
.compl_nr
)
2136 io_submit_flush_completions(ctx
);
2138 spin_lock_irq(&tctx
->task_lock
);
2139 node
= tctx
->task_list
.first
;
2140 INIT_WQ_LIST(&tctx
->task_list
);
2142 tctx
->task_running
= false;
2143 spin_unlock_irq(&tctx
->task_lock
);
2148 struct io_wq_work_node
*next
= node
->next
;
2149 struct io_kiocb
*req
= container_of(node
, struct io_kiocb
,
2152 if (req
->ctx
!= ctx
) {
2153 ctx_flush_and_put(ctx
, &locked
);
2155 /* if not contended, grab and improve batching */
2156 locked
= mutex_trylock(&ctx
->uring_lock
);
2157 percpu_ref_get(&ctx
->refs
);
2159 req
->io_task_work
.func(req
, &locked
);
2166 ctx_flush_and_put(ctx
, &locked
);
2169 static void io_req_task_work_add(struct io_kiocb
*req
)
2171 struct task_struct
*tsk
= req
->task
;
2172 struct io_uring_task
*tctx
= tsk
->io_uring
;
2173 enum task_work_notify_mode notify
;
2174 struct io_wq_work_node
*node
;
2175 unsigned long flags
;
2178 WARN_ON_ONCE(!tctx
);
2180 spin_lock_irqsave(&tctx
->task_lock
, flags
);
2181 wq_list_add_tail(&req
->io_task_work
.node
, &tctx
->task_list
);
2182 running
= tctx
->task_running
;
2184 tctx
->task_running
= true;
2185 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
2187 /* task_work already pending, we're done */
2192 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2193 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2194 * processing task_work. There's no reliable way to tell if TWA_RESUME
2197 notify
= (req
->ctx
->flags
& IORING_SETUP_SQPOLL
) ? TWA_NONE
: TWA_SIGNAL
;
2198 if (!task_work_add(tsk
, &tctx
->task_work
, notify
)) {
2199 wake_up_process(tsk
);
2203 spin_lock_irqsave(&tctx
->task_lock
, flags
);
2204 tctx
->task_running
= false;
2205 node
= tctx
->task_list
.first
;
2206 INIT_WQ_LIST(&tctx
->task_list
);
2207 spin_unlock_irqrestore(&tctx
->task_lock
, flags
);
2210 req
= container_of(node
, struct io_kiocb
, io_task_work
.node
);
2212 if (llist_add(&req
->io_task_work
.fallback_node
,
2213 &req
->ctx
->fallback_llist
))
2214 schedule_delayed_work(&req
->ctx
->fallback_work
, 1);
2218 static void io_req_task_cancel(struct io_kiocb
*req
, bool *locked
)
2220 struct io_ring_ctx
*ctx
= req
->ctx
;
2222 /* not needed for normal modes, but SQPOLL depends on it */
2223 io_tw_lock(ctx
, locked
);
2224 io_req_complete_failed(req
, req
->result
);
2227 static void io_req_task_submit(struct io_kiocb
*req
, bool *locked
)
2229 struct io_ring_ctx
*ctx
= req
->ctx
;
2231 io_tw_lock(ctx
, locked
);
2232 /* req->task == current here, checking PF_EXITING is safe */
2233 if (likely(!(req
->task
->flags
& PF_EXITING
)))
2234 __io_queue_sqe(req
);
2236 io_req_complete_failed(req
, -EFAULT
);
2239 static void io_req_task_queue_fail(struct io_kiocb
*req
, int ret
)
2242 req
->io_task_work
.func
= io_req_task_cancel
;
2243 io_req_task_work_add(req
);
2246 static void io_req_task_queue(struct io_kiocb
*req
)
2248 req
->io_task_work
.func
= io_req_task_submit
;
2249 io_req_task_work_add(req
);
2252 static void io_req_task_queue_reissue(struct io_kiocb
*req
)
2254 req
->io_task_work
.func
= io_queue_async_work
;
2255 io_req_task_work_add(req
);
2258 static inline void io_queue_next(struct io_kiocb
*req
)
2260 struct io_kiocb
*nxt
= io_req_find_next(req
);
2263 io_req_task_queue(nxt
);
2266 static void io_free_req(struct io_kiocb
*req
)
2272 static void io_free_req_work(struct io_kiocb
*req
, bool *locked
)
2278 struct task_struct
*task
;
2283 static inline void io_init_req_batch(struct req_batch
*rb
)
2290 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2291 struct req_batch
*rb
)
2294 percpu_ref_put_many(&ctx
->refs
, rb
->ctx_refs
);
2296 io_put_task(rb
->task
, rb
->task_refs
);
2299 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
,
2300 struct io_submit_state
*state
)
2303 io_dismantle_req(req
);
2305 if (req
->task
!= rb
->task
) {
2307 io_put_task(rb
->task
, rb
->task_refs
);
2308 rb
->task
= req
->task
;
2314 if (state
->free_reqs
!= ARRAY_SIZE(state
->reqs
))
2315 state
->reqs
[state
->free_reqs
++] = req
;
2317 list_add(&req
->inflight_entry
, &state
->free_list
);
2320 static void io_submit_flush_completions(struct io_ring_ctx
*ctx
)
2321 __must_hold(&ctx
->uring_lock
)
2323 struct io_submit_state
*state
= &ctx
->submit_state
;
2324 int i
, nr
= state
->compl_nr
;
2325 struct req_batch rb
;
2327 spin_lock(&ctx
->completion_lock
);
2328 for (i
= 0; i
< nr
; i
++) {
2329 struct io_kiocb
*req
= state
->compl_reqs
[i
];
2331 __io_cqring_fill_event(ctx
, req
->user_data
, req
->result
,
2334 io_commit_cqring(ctx
);
2335 spin_unlock(&ctx
->completion_lock
);
2336 io_cqring_ev_posted(ctx
);
2338 io_init_req_batch(&rb
);
2339 for (i
= 0; i
< nr
; i
++) {
2340 struct io_kiocb
*req
= state
->compl_reqs
[i
];
2342 if (req_ref_put_and_test(req
))
2343 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2346 io_req_free_batch_finish(ctx
, &rb
);
2347 state
->compl_nr
= 0;
2351 * Drop reference to request, return next in chain (if there is one) if this
2352 * was the last reference to this request.
2354 static inline struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2356 struct io_kiocb
*nxt
= NULL
;
2358 if (req_ref_put_and_test(req
)) {
2359 nxt
= io_req_find_next(req
);
2365 static inline void io_put_req(struct io_kiocb
*req
)
2367 if (req_ref_put_and_test(req
))
2371 static inline void io_put_req_deferred(struct io_kiocb
*req
)
2373 if (req_ref_put_and_test(req
)) {
2374 req
->io_task_work
.func
= io_free_req_work
;
2375 io_req_task_work_add(req
);
2379 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
)
2381 /* See comment at the top of this file */
2383 return __io_cqring_events(ctx
);
2386 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2388 struct io_rings
*rings
= ctx
->rings
;
2390 /* make sure SQ entry isn't read before tail */
2391 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2394 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2396 unsigned int cflags
;
2398 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2399 cflags
|= IORING_CQE_F_BUFFER
;
2400 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2405 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2407 struct io_buffer
*kbuf
;
2409 if (likely(!(req
->flags
& REQ_F_BUFFER_SELECTED
)))
2411 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2412 return io_put_kbuf(req
, kbuf
);
2415 static inline bool io_run_task_work(void)
2417 if (test_thread_flag(TIF_NOTIFY_SIGNAL
) || current
->task_works
) {
2418 __set_current_state(TASK_RUNNING
);
2419 tracehook_notify_signal();
2427 * Find and free completed poll iocbs
2429 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2430 struct list_head
*done
)
2432 struct req_batch rb
;
2433 struct io_kiocb
*req
;
2435 /* order with ->result store in io_complete_rw_iopoll() */
2438 io_init_req_batch(&rb
);
2439 while (!list_empty(done
)) {
2440 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2441 list_del(&req
->inflight_entry
);
2443 __io_cqring_fill_event(ctx
, req
->user_data
, req
->result
,
2444 io_put_rw_kbuf(req
));
2447 if (req_ref_put_and_test(req
))
2448 io_req_free_batch(&rb
, req
, &ctx
->submit_state
);
2451 io_commit_cqring(ctx
);
2452 io_cqring_ev_posted_iopoll(ctx
);
2453 io_req_free_batch_finish(ctx
, &rb
);
2456 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2459 struct io_kiocb
*req
, *tmp
;
2464 * Only spin for completions if we don't have multiple devices hanging
2465 * off our complete list, and we're under the requested amount.
2467 spin
= !ctx
->poll_multi_queue
&& *nr_events
< min
;
2469 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2470 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2474 * Move completed and retryable entries to our local lists.
2475 * If we find a request that requires polling, break out
2476 * and complete those lists first, if we have entries there.
2478 if (READ_ONCE(req
->iopoll_completed
)) {
2479 list_move_tail(&req
->inflight_entry
, &done
);
2482 if (!list_empty(&done
))
2485 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2486 if (unlikely(ret
< 0))
2491 /* iopoll may have completed current req */
2492 if (READ_ONCE(req
->iopoll_completed
))
2493 list_move_tail(&req
->inflight_entry
, &done
);
2496 if (!list_empty(&done
))
2497 io_iopoll_complete(ctx
, nr_events
, &done
);
2503 * We can't just wait for polled events to come to us, we have to actively
2504 * find and complete them.
2506 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2508 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2511 mutex_lock(&ctx
->uring_lock
);
2512 while (!list_empty(&ctx
->iopoll_list
)) {
2513 unsigned int nr_events
= 0;
2515 io_do_iopoll(ctx
, &nr_events
, 0);
2517 /* let it sleep and repeat later if can't complete a request */
2521 * Ensure we allow local-to-the-cpu processing to take place,
2522 * in this case we need to ensure that we reap all events.
2523 * Also let task_work, etc. to progress by releasing the mutex
2525 if (need_resched()) {
2526 mutex_unlock(&ctx
->uring_lock
);
2528 mutex_lock(&ctx
->uring_lock
);
2531 mutex_unlock(&ctx
->uring_lock
);
2534 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2536 unsigned int nr_events
= 0;
2540 * We disallow the app entering submit/complete with polling, but we
2541 * still need to lock the ring to prevent racing with polled issue
2542 * that got punted to a workqueue.
2544 mutex_lock(&ctx
->uring_lock
);
2546 * Don't enter poll loop if we already have events pending.
2547 * If we do, we can potentially be spinning for commands that
2548 * already triggered a CQE (eg in error).
2550 if (test_bit(0, &ctx
->check_cq_overflow
))
2551 __io_cqring_overflow_flush(ctx
, false);
2552 if (io_cqring_events(ctx
))
2556 * If a submit got punted to a workqueue, we can have the
2557 * application entering polling for a command before it gets
2558 * issued. That app will hold the uring_lock for the duration
2559 * of the poll right here, so we need to take a breather every
2560 * now and then to ensure that the issue has a chance to add
2561 * the poll to the issued list. Otherwise we can spin here
2562 * forever, while the workqueue is stuck trying to acquire the
2565 if (list_empty(&ctx
->iopoll_list
)) {
2566 u32 tail
= ctx
->cached_cq_tail
;
2568 mutex_unlock(&ctx
->uring_lock
);
2570 mutex_lock(&ctx
->uring_lock
);
2572 /* some requests don't go through iopoll_list */
2573 if (tail
!= ctx
->cached_cq_tail
||
2574 list_empty(&ctx
->iopoll_list
))
2577 ret
= io_do_iopoll(ctx
, &nr_events
, min
);
2578 } while (!ret
&& nr_events
< min
&& !need_resched());
2580 mutex_unlock(&ctx
->uring_lock
);
2584 static void kiocb_end_write(struct io_kiocb
*req
)
2587 * Tell lockdep we inherited freeze protection from submission
2590 if (req
->flags
& REQ_F_ISREG
) {
2591 struct super_block
*sb
= file_inode(req
->file
)->i_sb
;
2593 __sb_writers_acquired(sb
, SB_FREEZE_WRITE
);
2599 static bool io_resubmit_prep(struct io_kiocb
*req
)
2601 struct io_async_rw
*rw
= req
->async_data
;
2604 return !io_req_prep_async(req
);
2605 iov_iter_restore(&rw
->iter
, &rw
->iter_state
);
2609 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2611 umode_t mode
= file_inode(req
->file
)->i_mode
;
2612 struct io_ring_ctx
*ctx
= req
->ctx
;
2614 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2616 if ((req
->flags
& REQ_F_NOWAIT
) || (io_wq_current_is_worker() &&
2617 !(ctx
->flags
& IORING_SETUP_IOPOLL
)))
2620 * If ref is dying, we might be running poll reap from the exit work.
2621 * Don't attempt to reissue from that path, just let it fail with
2624 if (percpu_ref_is_dying(&ctx
->refs
))
2627 * Play it safe and assume not safe to re-import and reissue if we're
2628 * not in the original thread group (or in task context).
2630 if (!same_thread_group(req
->task
, current
) || !in_task())
2635 static bool io_resubmit_prep(struct io_kiocb
*req
)
2639 static bool io_rw_should_reissue(struct io_kiocb
*req
)
2645 static bool __io_complete_rw_common(struct io_kiocb
*req
, long res
)
2647 if (req
->rw
.kiocb
.ki_flags
& IOCB_WRITE
)
2648 kiocb_end_write(req
);
2649 if (res
!= req
->result
) {
2650 if ((res
== -EAGAIN
|| res
== -EOPNOTSUPP
) &&
2651 io_rw_should_reissue(req
)) {
2652 req
->flags
|= REQ_F_REISSUE
;
2661 static void io_req_task_complete(struct io_kiocb
*req
, bool *locked
)
2663 unsigned int cflags
= io_put_rw_kbuf(req
);
2664 long res
= req
->result
;
2667 struct io_ring_ctx
*ctx
= req
->ctx
;
2668 struct io_submit_state
*state
= &ctx
->submit_state
;
2670 io_req_complete_state(req
, res
, cflags
);
2671 state
->compl_reqs
[state
->compl_nr
++] = req
;
2672 if (state
->compl_nr
== ARRAY_SIZE(state
->compl_reqs
))
2673 io_submit_flush_completions(ctx
);
2675 io_req_complete_post(req
, res
, cflags
);
2679 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2680 unsigned int issue_flags
)
2682 if (__io_complete_rw_common(req
, res
))
2684 __io_req_complete(req
, issue_flags
, req
->result
, io_put_rw_kbuf(req
));
2687 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2689 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2691 if (__io_complete_rw_common(req
, res
))
2694 req
->io_task_work
.func
= io_req_task_complete
;
2695 io_req_task_work_add(req
);
2698 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2700 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2702 if (kiocb
->ki_flags
& IOCB_WRITE
)
2703 kiocb_end_write(req
);
2704 if (unlikely(res
!= req
->result
)) {
2705 if (res
== -EAGAIN
&& io_rw_should_reissue(req
)) {
2706 req
->flags
|= REQ_F_REISSUE
;
2711 WRITE_ONCE(req
->result
, res
);
2712 /* order with io_iopoll_complete() checking ->result */
2714 WRITE_ONCE(req
->iopoll_completed
, 1);
2718 * After the iocb has been issued, it's safe to be found on the poll list.
2719 * Adding the kiocb to the list AFTER submission ensures that we don't
2720 * find it from a io_do_iopoll() thread before the issuer is done
2721 * accessing the kiocb cookie.
2723 static void io_iopoll_req_issued(struct io_kiocb
*req
)
2725 struct io_ring_ctx
*ctx
= req
->ctx
;
2726 const bool in_async
= io_wq_current_is_worker();
2728 /* workqueue context doesn't hold uring_lock, grab it now */
2729 if (unlikely(in_async
))
2730 mutex_lock(&ctx
->uring_lock
);
2733 * Track whether we have multiple files in our lists. This will impact
2734 * how we do polling eventually, not spinning if we're on potentially
2735 * different devices.
2737 if (list_empty(&ctx
->iopoll_list
)) {
2738 ctx
->poll_multi_queue
= false;
2739 } else if (!ctx
->poll_multi_queue
) {
2740 struct io_kiocb
*list_req
;
2741 unsigned int queue_num0
, queue_num1
;
2743 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2746 if (list_req
->file
!= req
->file
) {
2747 ctx
->poll_multi_queue
= true;
2749 queue_num0
= blk_qc_t_to_queue_num(list_req
->rw
.kiocb
.ki_cookie
);
2750 queue_num1
= blk_qc_t_to_queue_num(req
->rw
.kiocb
.ki_cookie
);
2751 if (queue_num0
!= queue_num1
)
2752 ctx
->poll_multi_queue
= true;
2757 * For fast devices, IO may have already completed. If it has, add
2758 * it to the front so we find it first.
2760 if (READ_ONCE(req
->iopoll_completed
))
2761 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2763 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2765 if (unlikely(in_async
)) {
2767 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
2768 * in sq thread task context or in io worker task context. If
2769 * current task context is sq thread, we don't need to check
2770 * whether should wake up sq thread.
2772 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2773 wq_has_sleeper(&ctx
->sq_data
->wait
))
2774 wake_up(&ctx
->sq_data
->wait
);
2776 mutex_unlock(&ctx
->uring_lock
);
2780 static bool io_bdev_nowait(struct block_device
*bdev
)
2782 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2786 * If we tracked the file through the SCM inflight mechanism, we could support
2787 * any file. For now, just ensure that anything potentially problematic is done
2790 static bool __io_file_supports_nowait(struct file
*file
, int rw
)
2792 umode_t mode
= file_inode(file
)->i_mode
;
2794 if (S_ISBLK(mode
)) {
2795 if (IS_ENABLED(CONFIG_BLOCK
) &&
2796 io_bdev_nowait(I_BDEV(file
->f_mapping
->host
)))
2802 if (S_ISREG(mode
)) {
2803 if (IS_ENABLED(CONFIG_BLOCK
) &&
2804 io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2805 file
->f_op
!= &io_uring_fops
)
2810 /* any ->read/write should understand O_NONBLOCK */
2811 if (file
->f_flags
& O_NONBLOCK
)
2814 if (!(file
->f_mode
& FMODE_NOWAIT
))
2818 return file
->f_op
->read_iter
!= NULL
;
2820 return file
->f_op
->write_iter
!= NULL
;
2823 static bool io_file_supports_nowait(struct io_kiocb
*req
, int rw
)
2825 if (rw
== READ
&& (req
->flags
& REQ_F_NOWAIT_READ
))
2827 else if (rw
== WRITE
&& (req
->flags
& REQ_F_NOWAIT_WRITE
))
2830 return __io_file_supports_nowait(req
->file
, rw
);
2833 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2836 struct io_ring_ctx
*ctx
= req
->ctx
;
2837 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2838 struct file
*file
= req
->file
;
2842 if (!io_req_ffs_set(req
) && S_ISREG(file_inode(file
)->i_mode
))
2843 req
->flags
|= REQ_F_ISREG
;
2845 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2846 if (kiocb
->ki_pos
== -1 && !(file
->f_mode
& FMODE_STREAM
)) {
2847 req
->flags
|= REQ_F_CUR_POS
;
2848 kiocb
->ki_pos
= file
->f_pos
;
2850 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2851 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2852 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2857 * If the file is marked O_NONBLOCK, still allow retry for it if it
2858 * supports async. Otherwise it's impossible to use O_NONBLOCK files
2859 * reliably. If not, or it IOCB_NOWAIT is set, don't retry.
2861 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) ||
2862 ((file
->f_flags
& O_NONBLOCK
) && !io_file_supports_nowait(req
, rw
)))
2863 req
->flags
|= REQ_F_NOWAIT
;
2865 ioprio
= READ_ONCE(sqe
->ioprio
);
2867 ret
= ioprio_check_cap(ioprio
);
2871 kiocb
->ki_ioprio
= ioprio
;
2873 kiocb
->ki_ioprio
= get_current_ioprio();
2875 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2876 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2877 !kiocb
->ki_filp
->f_op
->iopoll
)
2880 kiocb
->ki_flags
|= IOCB_HIPRI
| IOCB_ALLOC_CACHE
;
2881 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2882 req
->iopoll_completed
= 0;
2884 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2886 kiocb
->ki_complete
= io_complete_rw
;
2889 if (req
->opcode
== IORING_OP_READ_FIXED
||
2890 req
->opcode
== IORING_OP_WRITE_FIXED
) {
2892 io_req_set_rsrc_node(req
);
2895 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2896 req
->rw
.len
= READ_ONCE(sqe
->len
);
2897 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2901 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2907 case -ERESTARTNOINTR
:
2908 case -ERESTARTNOHAND
:
2909 case -ERESTART_RESTARTBLOCK
:
2911 * We can't just restart the syscall, since previously
2912 * submitted sqes may already be in progress. Just fail this
2918 kiocb
->ki_complete(kiocb
, ret
, 0);
2922 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2923 unsigned int issue_flags
)
2925 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2926 struct io_async_rw
*io
= req
->async_data
;
2928 /* add previously done IO, if any */
2929 if (io
&& io
->bytes_done
> 0) {
2931 ret
= io
->bytes_done
;
2933 ret
+= io
->bytes_done
;
2936 if (req
->flags
& REQ_F_CUR_POS
)
2937 req
->file
->f_pos
= kiocb
->ki_pos
;
2938 if (ret
>= 0 && (kiocb
->ki_complete
== io_complete_rw
))
2939 __io_complete_rw(req
, ret
, 0, issue_flags
);
2941 io_rw_done(kiocb
, ret
);
2943 if (req
->flags
& REQ_F_REISSUE
) {
2944 req
->flags
&= ~REQ_F_REISSUE
;
2945 if (io_resubmit_prep(req
)) {
2946 io_req_task_queue_reissue(req
);
2948 unsigned int cflags
= io_put_rw_kbuf(req
);
2949 struct io_ring_ctx
*ctx
= req
->ctx
;
2952 if (!(issue_flags
& IO_URING_F_NONBLOCK
)) {
2953 mutex_lock(&ctx
->uring_lock
);
2954 __io_req_complete(req
, issue_flags
, ret
, cflags
);
2955 mutex_unlock(&ctx
->uring_lock
);
2957 __io_req_complete(req
, issue_flags
, ret
, cflags
);
2963 static int __io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
,
2964 struct io_mapped_ubuf
*imu
)
2966 size_t len
= req
->rw
.len
;
2967 u64 buf_end
, buf_addr
= req
->rw
.addr
;
2970 if (unlikely(check_add_overflow(buf_addr
, (u64
)len
, &buf_end
)))
2972 /* not inside the mapped region */
2973 if (unlikely(buf_addr
< imu
->ubuf
|| buf_end
> imu
->ubuf_end
))
2977 * May not be a start of buffer, set size appropriately
2978 * and advance us to the beginning.
2980 offset
= buf_addr
- imu
->ubuf
;
2981 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2985 * Don't use iov_iter_advance() here, as it's really slow for
2986 * using the latter parts of a big fixed buffer - it iterates
2987 * over each segment manually. We can cheat a bit here, because
2990 * 1) it's a BVEC iter, we set it up
2991 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2992 * first and last bvec
2994 * So just find our index, and adjust the iterator afterwards.
2995 * If the offset is within the first bvec (or the whole first
2996 * bvec, just use iov_iter_advance(). This makes it easier
2997 * since we can just skip the first segment, which may not
2998 * be PAGE_SIZE aligned.
3000 const struct bio_vec
*bvec
= imu
->bvec
;
3002 if (offset
<= bvec
->bv_len
) {
3003 iov_iter_advance(iter
, offset
);
3005 unsigned long seg_skip
;
3007 /* skip first vec */
3008 offset
-= bvec
->bv_len
;
3009 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
3011 iter
->bvec
= bvec
+ seg_skip
;
3012 iter
->nr_segs
-= seg_skip
;
3013 iter
->count
-= bvec
->bv_len
+ offset
;
3014 iter
->iov_offset
= offset
& ~PAGE_MASK
;
3021 static int io_import_fixed(struct io_kiocb
*req
, int rw
, struct iov_iter
*iter
)
3023 struct io_ring_ctx
*ctx
= req
->ctx
;
3024 struct io_mapped_ubuf
*imu
= req
->imu
;
3025 u16 index
, buf_index
= req
->buf_index
;
3028 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
3030 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
3031 imu
= READ_ONCE(ctx
->user_bufs
[index
]);
3034 return __io_import_fixed(req
, rw
, iter
, imu
);
3037 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3040 mutex_unlock(&ctx
->uring_lock
);
3043 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
3046 * "Normal" inline submissions always hold the uring_lock, since we
3047 * grab it from the system call. Same is true for the SQPOLL offload.
3048 * The only exception is when we've detached the request and issue it
3049 * from an async worker thread, grab the lock for that case.
3052 mutex_lock(&ctx
->uring_lock
);
3055 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
3056 int bgid
, struct io_buffer
*kbuf
,
3059 struct io_buffer
*head
;
3061 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
3064 io_ring_submit_lock(req
->ctx
, needs_lock
);
3066 lockdep_assert_held(&req
->ctx
->uring_lock
);
3068 head
= xa_load(&req
->ctx
->io_buffers
, bgid
);
3070 if (!list_empty(&head
->list
)) {
3071 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
3073 list_del(&kbuf
->list
);
3076 xa_erase(&req
->ctx
->io_buffers
, bgid
);
3078 if (*len
> kbuf
->len
)
3081 kbuf
= ERR_PTR(-ENOBUFS
);
3084 io_ring_submit_unlock(req
->ctx
, needs_lock
);
3089 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
3092 struct io_buffer
*kbuf
;
3095 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3096 bgid
= req
->buf_index
;
3097 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
3100 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
3101 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3102 return u64_to_user_ptr(kbuf
->addr
);
3105 #ifdef CONFIG_COMPAT
3106 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
3109 struct compat_iovec __user
*uiov
;
3110 compat_ssize_t clen
;
3114 uiov
= u64_to_user_ptr(req
->rw
.addr
);
3115 if (!access_ok(uiov
, sizeof(*uiov
)))
3117 if (__get_user(clen
, &uiov
->iov_len
))
3123 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3125 return PTR_ERR(buf
);
3126 iov
[0].iov_base
= buf
;
3127 iov
[0].iov_len
= (compat_size_t
) len
;
3132 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3135 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
3139 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3142 len
= iov
[0].iov_len
;
3145 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3147 return PTR_ERR(buf
);
3148 iov
[0].iov_base
= buf
;
3149 iov
[0].iov_len
= len
;
3153 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3156 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3157 struct io_buffer
*kbuf
;
3159 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3160 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3161 iov
[0].iov_len
= kbuf
->len
;
3164 if (req
->rw
.len
!= 1)
3167 #ifdef CONFIG_COMPAT
3168 if (req
->ctx
->compat
)
3169 return io_compat_import(req
, iov
, needs_lock
);
3172 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3175 static int io_import_iovec(int rw
, struct io_kiocb
*req
, struct iovec
**iovec
,
3176 struct iov_iter
*iter
, bool needs_lock
)
3178 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3179 size_t sqe_len
= req
->rw
.len
;
3180 u8 opcode
= req
->opcode
;
3183 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3185 return io_import_fixed(req
, rw
, iter
);
3188 /* buffer index only valid with fixed read/write, or buffer select */
3189 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3192 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3193 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3194 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3196 return PTR_ERR(buf
);
3197 req
->rw
.len
= sqe_len
;
3200 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3205 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3206 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3208 iov_iter_init(iter
, rw
, *iovec
, 1, (*iovec
)->iov_len
);
3213 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3217 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3219 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3223 * For files that don't have ->read_iter() and ->write_iter(), handle them
3224 * by looping over ->read() or ->write() manually.
3226 static ssize_t
loop_rw_iter(int rw
, struct io_kiocb
*req
, struct iov_iter
*iter
)
3228 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3229 struct file
*file
= req
->file
;
3233 * Don't support polled IO through this interface, and we can't
3234 * support non-blocking either. For the latter, this just causes
3235 * the kiocb to be handled from an async context.
3237 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3239 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3242 while (iov_iter_count(iter
)) {
3246 if (!iov_iter_is_bvec(iter
)) {
3247 iovec
= iov_iter_iovec(iter
);
3249 iovec
.iov_base
= u64_to_user_ptr(req
->rw
.addr
);
3250 iovec
.iov_len
= req
->rw
.len
;
3254 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3255 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3257 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3258 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3266 if (!iov_iter_is_bvec(iter
)) {
3267 iov_iter_advance(iter
, nr
);
3273 if (nr
!= iovec
.iov_len
)
3280 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3281 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3283 struct io_async_rw
*rw
= req
->async_data
;
3285 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3286 rw
->free_iovec
= iovec
;
3288 /* can only be fixed buffers, no need to do anything */
3289 if (iov_iter_is_bvec(iter
))
3292 unsigned iov_off
= 0;
3294 rw
->iter
.iov
= rw
->fast_iov
;
3295 if (iter
->iov
!= fast_iov
) {
3296 iov_off
= iter
->iov
- fast_iov
;
3297 rw
->iter
.iov
+= iov_off
;
3299 if (rw
->fast_iov
!= fast_iov
)
3300 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3301 sizeof(struct iovec
) * iter
->nr_segs
);
3303 req
->flags
|= REQ_F_NEED_CLEANUP
;
3307 static inline int io_alloc_async_data(struct io_kiocb
*req
)
3309 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3310 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3311 return req
->async_data
== NULL
;
3314 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3315 const struct iovec
*fast_iov
,
3316 struct iov_iter
*iter
, bool force
)
3318 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_setup
)
3320 if (!req
->async_data
) {
3321 struct io_async_rw
*iorw
;
3323 if (io_alloc_async_data(req
)) {
3328 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3329 iorw
= req
->async_data
;
3330 /* we've copied and mapped the iter, ensure state is saved */
3331 iov_iter_save_state(&iorw
->iter
, &iorw
->iter_state
);
3336 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3338 struct io_async_rw
*iorw
= req
->async_data
;
3339 struct iovec
*iov
= iorw
->fast_iov
;
3342 ret
= io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3343 if (unlikely(ret
< 0))
3346 iorw
->bytes_done
= 0;
3347 iorw
->free_iovec
= iov
;
3349 req
->flags
|= REQ_F_NEED_CLEANUP
;
3350 iov_iter_save_state(&iorw
->iter
, &iorw
->iter_state
);
3354 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3356 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3358 return io_prep_rw(req
, sqe
, READ
);
3362 * This is our waitqueue callback handler, registered through lock_page_async()
3363 * when we initially tried to do the IO with the iocb armed our waitqueue.
3364 * This gets called when the page is unlocked, and we generally expect that to
3365 * happen when the page IO is completed and the page is now uptodate. This will
3366 * queue a task_work based retry of the operation, attempting to copy the data
3367 * again. If the latter fails because the page was NOT uptodate, then we will
3368 * do a thread based blocking retry of the operation. That's the unexpected
3371 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3372 int sync
, void *arg
)
3374 struct wait_page_queue
*wpq
;
3375 struct io_kiocb
*req
= wait
->private;
3376 struct wait_page_key
*key
= arg
;
3378 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3380 if (!wake_page_match(wpq
, key
))
3383 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3384 list_del_init(&wait
->entry
);
3385 io_req_task_queue(req
);
3390 * This controls whether a given IO request should be armed for async page
3391 * based retry. If we return false here, the request is handed to the async
3392 * worker threads for retry. If we're doing buffered reads on a regular file,
3393 * we prepare a private wait_page_queue entry and retry the operation. This
3394 * will either succeed because the page is now uptodate and unlocked, or it
3395 * will register a callback when the page is unlocked at IO completion. Through
3396 * that callback, io_uring uses task_work to setup a retry of the operation.
3397 * That retry will attempt the buffered read again. The retry will generally
3398 * succeed, or in rare cases where it fails, we then fall back to using the
3399 * async worker threads for a blocking retry.
3401 static bool io_rw_should_retry(struct io_kiocb
*req
)
3403 struct io_async_rw
*rw
= req
->async_data
;
3404 struct wait_page_queue
*wait
= &rw
->wpq
;
3405 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3407 /* never retry for NOWAIT, we just complete with -EAGAIN */
3408 if (req
->flags
& REQ_F_NOWAIT
)
3411 /* Only for buffered IO */
3412 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3416 * just use poll if we can, and don't attempt if the fs doesn't
3417 * support callback based unlocks
3419 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3422 wait
->wait
.func
= io_async_buf_func
;
3423 wait
->wait
.private = req
;
3424 wait
->wait
.flags
= 0;
3425 INIT_LIST_HEAD(&wait
->wait
.entry
);
3426 kiocb
->ki_flags
|= IOCB_WAITQ
;
3427 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3428 kiocb
->ki_waitq
= wait
;
3432 static inline int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3434 if (req
->file
->f_op
->read_iter
)
3435 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3436 else if (req
->file
->f_op
->read
)
3437 return loop_rw_iter(READ
, req
, iter
);
3442 static bool need_read_all(struct io_kiocb
*req
)
3444 return req
->flags
& REQ_F_ISREG
||
3445 S_ISBLK(file_inode(req
->file
)->i_mode
);
3448 static int io_read(struct io_kiocb
*req
, unsigned int issue_flags
)
3450 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3451 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3452 struct iov_iter __iter
, *iter
= &__iter
;
3453 struct io_async_rw
*rw
= req
->async_data
;
3454 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3455 struct iov_iter_state __state
, *state
;
3460 state
= &rw
->iter_state
;
3462 * We come here from an earlier attempt, restore our state to
3463 * match in case it doesn't. It's cheap enough that we don't
3464 * need to make this conditional.
3466 iov_iter_restore(iter
, state
);
3469 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3473 iov_iter_save_state(iter
, state
);
3475 req
->result
= iov_iter_count(iter
);
3477 /* Ensure we clear previously set non-block flag */
3478 if (!force_nonblock
)
3479 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3481 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3483 /* If the file doesn't support async, just async punt */
3484 if (force_nonblock
&& !io_file_supports_nowait(req
, READ
)) {
3485 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3486 return ret
?: -EAGAIN
;
3489 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), req
->result
);
3490 if (unlikely(ret
)) {
3495 ret
= io_iter_do_read(req
, iter
);
3497 if (ret
== -EAGAIN
|| (req
->flags
& REQ_F_REISSUE
)) {
3498 req
->flags
&= ~REQ_F_REISSUE
;
3499 /* IOPOLL retry should happen for io-wq threads */
3500 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3502 /* no retry on NONBLOCK nor RWF_NOWAIT */
3503 if (req
->flags
& REQ_F_NOWAIT
)
3506 } else if (ret
== -EIOCBQUEUED
) {
3508 } else if (ret
<= 0 || ret
== req
->result
|| !force_nonblock
||
3509 (req
->flags
& REQ_F_NOWAIT
) || !need_read_all(req
)) {
3510 /* read all, failed, already did sync or don't want to retry */
3515 * Don't depend on the iter state matching what was consumed, or being
3516 * untouched in case of error. Restore it and we'll advance it
3517 * manually if we need to.
3519 iov_iter_restore(iter
, state
);
3521 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3526 rw
= req
->async_data
;
3528 * Now use our persistent iterator and state, if we aren't already.
3529 * We've restored and mapped the iter to match.
3531 if (iter
!= &rw
->iter
) {
3533 state
= &rw
->iter_state
;
3538 * We end up here because of a partial read, either from
3539 * above or inside this loop. Advance the iter by the bytes
3540 * that were consumed.
3542 iov_iter_advance(iter
, ret
);
3543 if (!iov_iter_count(iter
))
3545 rw
->bytes_done
+= ret
;
3546 iov_iter_save_state(iter
, state
);
3548 /* if we can retry, do so with the callbacks armed */
3549 if (!io_rw_should_retry(req
)) {
3550 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3555 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3556 * we get -EIOCBQUEUED, then we'll get a notification when the
3557 * desired page gets unlocked. We can also get a partial read
3558 * here, and if we do, then just retry at the new offset.
3560 ret
= io_iter_do_read(req
, iter
);
3561 if (ret
== -EIOCBQUEUED
)
3563 /* we got some bytes, but not all. retry. */
3564 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3565 iov_iter_restore(iter
, state
);
3568 kiocb_done(kiocb
, ret
, issue_flags
);
3570 /* it's faster to check here then delegate to kfree */
3576 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3578 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3580 return io_prep_rw(req
, sqe
, WRITE
);
3583 static int io_write(struct io_kiocb
*req
, unsigned int issue_flags
)
3585 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3586 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3587 struct iov_iter __iter
, *iter
= &__iter
;
3588 struct io_async_rw
*rw
= req
->async_data
;
3589 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
3590 struct iov_iter_state __state
, *state
;
3595 state
= &rw
->iter_state
;
3596 iov_iter_restore(iter
, state
);
3599 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3603 iov_iter_save_state(iter
, state
);
3605 req
->result
= iov_iter_count(iter
);
3607 /* Ensure we clear previously set non-block flag */
3608 if (!force_nonblock
)
3609 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3611 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3613 /* If the file doesn't support async, just async punt */
3614 if (force_nonblock
&& !io_file_supports_nowait(req
, WRITE
))
3617 /* file path doesn't support NOWAIT for non-direct_IO */
3618 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3619 (req
->flags
& REQ_F_ISREG
))
3622 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), req
->result
);
3627 * Open-code file_start_write here to grab freeze protection,
3628 * which will be released by another thread in
3629 * io_complete_rw(). Fool lockdep by telling it the lock got
3630 * released so that it doesn't complain about the held lock when
3631 * we return to userspace.
3633 if (req
->flags
& REQ_F_ISREG
) {
3634 sb_start_write(file_inode(req
->file
)->i_sb
);
3635 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3638 kiocb
->ki_flags
|= IOCB_WRITE
;
3640 if (req
->file
->f_op
->write_iter
)
3641 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3642 else if (req
->file
->f_op
->write
)
3643 ret2
= loop_rw_iter(WRITE
, req
, iter
);
3647 if (req
->flags
& REQ_F_REISSUE
) {
3648 req
->flags
&= ~REQ_F_REISSUE
;
3653 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3654 * retry them without IOCB_NOWAIT.
3656 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3658 /* no retry on NONBLOCK nor RWF_NOWAIT */
3659 if (ret2
== -EAGAIN
&& (req
->flags
& REQ_F_NOWAIT
))
3661 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3662 /* IOPOLL retry should happen for io-wq threads */
3663 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3666 kiocb_done(kiocb
, ret2
, issue_flags
);
3669 iov_iter_restore(iter
, state
);
3670 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3671 return ret
?: -EAGAIN
;
3674 /* it's reportedly faster than delegating the null check to kfree() */
3680 static int io_renameat_prep(struct io_kiocb
*req
,
3681 const struct io_uring_sqe
*sqe
)
3683 struct io_rename
*ren
= &req
->rename
;
3684 const char __user
*oldf
, *newf
;
3686 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3688 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
3690 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3693 ren
->old_dfd
= READ_ONCE(sqe
->fd
);
3694 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3695 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3696 ren
->new_dfd
= READ_ONCE(sqe
->len
);
3697 ren
->flags
= READ_ONCE(sqe
->rename_flags
);
3699 ren
->oldpath
= getname(oldf
);
3700 if (IS_ERR(ren
->oldpath
))
3701 return PTR_ERR(ren
->oldpath
);
3703 ren
->newpath
= getname(newf
);
3704 if (IS_ERR(ren
->newpath
)) {
3705 putname(ren
->oldpath
);
3706 return PTR_ERR(ren
->newpath
);
3709 req
->flags
|= REQ_F_NEED_CLEANUP
;
3713 static int io_renameat(struct io_kiocb
*req
, unsigned int issue_flags
)
3715 struct io_rename
*ren
= &req
->rename
;
3718 if (issue_flags
& IO_URING_F_NONBLOCK
)
3721 ret
= do_renameat2(ren
->old_dfd
, ren
->oldpath
, ren
->new_dfd
,
3722 ren
->newpath
, ren
->flags
);
3724 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3727 io_req_complete(req
, ret
);
3731 static int io_unlinkat_prep(struct io_kiocb
*req
,
3732 const struct io_uring_sqe
*sqe
)
3734 struct io_unlink
*un
= &req
->unlink
;
3735 const char __user
*fname
;
3737 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3739 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
3742 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3745 un
->dfd
= READ_ONCE(sqe
->fd
);
3747 un
->flags
= READ_ONCE(sqe
->unlink_flags
);
3748 if (un
->flags
& ~AT_REMOVEDIR
)
3751 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3752 un
->filename
= getname(fname
);
3753 if (IS_ERR(un
->filename
))
3754 return PTR_ERR(un
->filename
);
3756 req
->flags
|= REQ_F_NEED_CLEANUP
;
3760 static int io_unlinkat(struct io_kiocb
*req
, unsigned int issue_flags
)
3762 struct io_unlink
*un
= &req
->unlink
;
3765 if (issue_flags
& IO_URING_F_NONBLOCK
)
3768 if (un
->flags
& AT_REMOVEDIR
)
3769 ret
= do_rmdir(un
->dfd
, un
->filename
);
3771 ret
= do_unlinkat(un
->dfd
, un
->filename
);
3773 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3776 io_req_complete(req
, ret
);
3780 static int io_mkdirat_prep(struct io_kiocb
*req
,
3781 const struct io_uring_sqe
*sqe
)
3783 struct io_mkdir
*mkd
= &req
->mkdir
;
3784 const char __user
*fname
;
3786 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3788 if (sqe
->ioprio
|| sqe
->off
|| sqe
->rw_flags
|| sqe
->buf_index
||
3791 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3794 mkd
->dfd
= READ_ONCE(sqe
->fd
);
3795 mkd
->mode
= READ_ONCE(sqe
->len
);
3797 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3798 mkd
->filename
= getname(fname
);
3799 if (IS_ERR(mkd
->filename
))
3800 return PTR_ERR(mkd
->filename
);
3802 req
->flags
|= REQ_F_NEED_CLEANUP
;
3806 static int io_mkdirat(struct io_kiocb
*req
, int issue_flags
)
3808 struct io_mkdir
*mkd
= &req
->mkdir
;
3811 if (issue_flags
& IO_URING_F_NONBLOCK
)
3814 ret
= do_mkdirat(mkd
->dfd
, mkd
->filename
, mkd
->mode
);
3816 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3819 io_req_complete(req
, ret
);
3823 static int io_symlinkat_prep(struct io_kiocb
*req
,
3824 const struct io_uring_sqe
*sqe
)
3826 struct io_symlink
*sl
= &req
->symlink
;
3827 const char __user
*oldpath
, *newpath
;
3829 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3831 if (sqe
->ioprio
|| sqe
->len
|| sqe
->rw_flags
|| sqe
->buf_index
||
3834 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3837 sl
->new_dfd
= READ_ONCE(sqe
->fd
);
3838 oldpath
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3839 newpath
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3841 sl
->oldpath
= getname(oldpath
);
3842 if (IS_ERR(sl
->oldpath
))
3843 return PTR_ERR(sl
->oldpath
);
3845 sl
->newpath
= getname(newpath
);
3846 if (IS_ERR(sl
->newpath
)) {
3847 putname(sl
->oldpath
);
3848 return PTR_ERR(sl
->newpath
);
3851 req
->flags
|= REQ_F_NEED_CLEANUP
;
3855 static int io_symlinkat(struct io_kiocb
*req
, int issue_flags
)
3857 struct io_symlink
*sl
= &req
->symlink
;
3860 if (issue_flags
& IO_URING_F_NONBLOCK
)
3863 ret
= do_symlinkat(sl
->oldpath
, sl
->new_dfd
, sl
->newpath
);
3865 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3868 io_req_complete(req
, ret
);
3872 static int io_linkat_prep(struct io_kiocb
*req
,
3873 const struct io_uring_sqe
*sqe
)
3875 struct io_hardlink
*lnk
= &req
->hardlink
;
3876 const char __user
*oldf
, *newf
;
3878 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3880 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
3882 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3885 lnk
->old_dfd
= READ_ONCE(sqe
->fd
);
3886 lnk
->new_dfd
= READ_ONCE(sqe
->len
);
3887 oldf
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3888 newf
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3889 lnk
->flags
= READ_ONCE(sqe
->hardlink_flags
);
3891 lnk
->oldpath
= getname(oldf
);
3892 if (IS_ERR(lnk
->oldpath
))
3893 return PTR_ERR(lnk
->oldpath
);
3895 lnk
->newpath
= getname(newf
);
3896 if (IS_ERR(lnk
->newpath
)) {
3897 putname(lnk
->oldpath
);
3898 return PTR_ERR(lnk
->newpath
);
3901 req
->flags
|= REQ_F_NEED_CLEANUP
;
3905 static int io_linkat(struct io_kiocb
*req
, int issue_flags
)
3907 struct io_hardlink
*lnk
= &req
->hardlink
;
3910 if (issue_flags
& IO_URING_F_NONBLOCK
)
3913 ret
= do_linkat(lnk
->old_dfd
, lnk
->oldpath
, lnk
->new_dfd
,
3914 lnk
->newpath
, lnk
->flags
);
3916 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3919 io_req_complete(req
, ret
);
3923 static int io_shutdown_prep(struct io_kiocb
*req
,
3924 const struct io_uring_sqe
*sqe
)
3926 #if defined(CONFIG_NET)
3927 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3929 if (unlikely(sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->rw_flags
||
3930 sqe
->buf_index
|| sqe
->splice_fd_in
))
3933 req
->shutdown
.how
= READ_ONCE(sqe
->len
);
3940 static int io_shutdown(struct io_kiocb
*req
, unsigned int issue_flags
)
3942 #if defined(CONFIG_NET)
3943 struct socket
*sock
;
3946 if (issue_flags
& IO_URING_F_NONBLOCK
)
3949 sock
= sock_from_file(req
->file
);
3950 if (unlikely(!sock
))
3953 ret
= __sys_shutdown_sock(sock
, req
->shutdown
.how
);
3956 io_req_complete(req
, ret
);
3963 static int __io_splice_prep(struct io_kiocb
*req
,
3964 const struct io_uring_sqe
*sqe
)
3966 struct io_splice
*sp
= &req
->splice
;
3967 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3969 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3973 sp
->len
= READ_ONCE(sqe
->len
);
3974 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3976 if (unlikely(sp
->flags
& ~valid_flags
))
3979 sp
->file_in
= io_file_get(req
->ctx
, req
, READ_ONCE(sqe
->splice_fd_in
),
3980 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3983 req
->flags
|= REQ_F_NEED_CLEANUP
;
3987 static int io_tee_prep(struct io_kiocb
*req
,
3988 const struct io_uring_sqe
*sqe
)
3990 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3992 return __io_splice_prep(req
, sqe
);
3995 static int io_tee(struct io_kiocb
*req
, unsigned int issue_flags
)
3997 struct io_splice
*sp
= &req
->splice
;
3998 struct file
*in
= sp
->file_in
;
3999 struct file
*out
= sp
->file_out
;
4000 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
4003 if (issue_flags
& IO_URING_F_NONBLOCK
)
4006 ret
= do_tee(in
, out
, sp
->len
, flags
);
4008 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
4010 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4014 io_req_complete(req
, ret
);
4018 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4020 struct io_splice
*sp
= &req
->splice
;
4022 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
4023 sp
->off_out
= READ_ONCE(sqe
->off
);
4024 return __io_splice_prep(req
, sqe
);
4027 static int io_splice(struct io_kiocb
*req
, unsigned int issue_flags
)
4029 struct io_splice
*sp
= &req
->splice
;
4030 struct file
*in
= sp
->file_in
;
4031 struct file
*out
= sp
->file_out
;
4032 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
4033 loff_t
*poff_in
, *poff_out
;
4036 if (issue_flags
& IO_URING_F_NONBLOCK
)
4039 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
4040 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
4043 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
4045 if (!(sp
->flags
& SPLICE_F_FD_IN_FIXED
))
4047 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4051 io_req_complete(req
, ret
);
4056 * IORING_OP_NOP just posts a completion event, nothing else.
4058 static int io_nop(struct io_kiocb
*req
, unsigned int issue_flags
)
4060 struct io_ring_ctx
*ctx
= req
->ctx
;
4062 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4065 __io_req_complete(req
, issue_flags
, 0, 0);
4069 static int io_fsync_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4071 struct io_ring_ctx
*ctx
= req
->ctx
;
4076 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4078 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
||
4082 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
4083 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
4086 req
->sync
.off
= READ_ONCE(sqe
->off
);
4087 req
->sync
.len
= READ_ONCE(sqe
->len
);
4091 static int io_fsync(struct io_kiocb
*req
, unsigned int issue_flags
)
4093 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
4096 /* fsync always requires a blocking context */
4097 if (issue_flags
& IO_URING_F_NONBLOCK
)
4100 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
4101 end
> 0 ? end
: LLONG_MAX
,
4102 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
4105 io_req_complete(req
, ret
);
4109 static int io_fallocate_prep(struct io_kiocb
*req
,
4110 const struct io_uring_sqe
*sqe
)
4112 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
||
4115 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4118 req
->sync
.off
= READ_ONCE(sqe
->off
);
4119 req
->sync
.len
= READ_ONCE(sqe
->addr
);
4120 req
->sync
.mode
= READ_ONCE(sqe
->len
);
4124 static int io_fallocate(struct io_kiocb
*req
, unsigned int issue_flags
)
4128 /* fallocate always requiring blocking context */
4129 if (issue_flags
& IO_URING_F_NONBLOCK
)
4131 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
4135 io_req_complete(req
, ret
);
4139 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4141 const char __user
*fname
;
4144 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4146 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
4148 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
4151 /* open.how should be already initialised */
4152 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
4153 req
->open
.how
.flags
|= O_LARGEFILE
;
4155 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
4156 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4157 req
->open
.filename
= getname(fname
);
4158 if (IS_ERR(req
->open
.filename
)) {
4159 ret
= PTR_ERR(req
->open
.filename
);
4160 req
->open
.filename
= NULL
;
4164 req
->open
.file_slot
= READ_ONCE(sqe
->file_index
);
4165 if (req
->open
.file_slot
&& (req
->open
.how
.flags
& O_CLOEXEC
))
4168 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
4169 req
->flags
|= REQ_F_NEED_CLEANUP
;
4173 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4175 u64 mode
= READ_ONCE(sqe
->len
);
4176 u64 flags
= READ_ONCE(sqe
->open_flags
);
4178 req
->open
.how
= build_open_how(flags
, mode
);
4179 return __io_openat_prep(req
, sqe
);
4182 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4184 struct open_how __user
*how
;
4188 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4189 len
= READ_ONCE(sqe
->len
);
4190 if (len
< OPEN_HOW_SIZE_VER0
)
4193 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
4198 return __io_openat_prep(req
, sqe
);
4201 static int io_openat2(struct io_kiocb
*req
, unsigned int issue_flags
)
4203 struct open_flags op
;
4205 bool resolve_nonblock
, nonblock_set
;
4206 bool fixed
= !!req
->open
.file_slot
;
4209 ret
= build_open_flags(&req
->open
.how
, &op
);
4212 nonblock_set
= op
.open_flag
& O_NONBLOCK
;
4213 resolve_nonblock
= req
->open
.how
.resolve
& RESOLVE_CACHED
;
4214 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4216 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
4217 * it'll always -EAGAIN
4219 if (req
->open
.how
.flags
& (O_TRUNC
| O_CREAT
| O_TMPFILE
))
4221 op
.lookup_flags
|= LOOKUP_CACHED
;
4222 op
.open_flag
|= O_NONBLOCK
;
4226 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
4231 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
4234 * We could hang on to this 'fd' on retrying, but seems like
4235 * marginal gain for something that is now known to be a slower
4236 * path. So just put it, and we'll get a new one when we retry.
4241 ret
= PTR_ERR(file
);
4242 /* only retry if RESOLVE_CACHED wasn't already set by application */
4243 if (ret
== -EAGAIN
&&
4244 (!resolve_nonblock
&& (issue_flags
& IO_URING_F_NONBLOCK
)))
4249 if ((issue_flags
& IO_URING_F_NONBLOCK
) && !nonblock_set
)
4250 file
->f_flags
&= ~O_NONBLOCK
;
4251 fsnotify_open(file
);
4254 fd_install(ret
, file
);
4256 ret
= io_install_fixed_file(req
, file
, issue_flags
,
4257 req
->open
.file_slot
- 1);
4259 putname(req
->open
.filename
);
4260 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4263 __io_req_complete(req
, issue_flags
, ret
, 0);
4267 static int io_openat(struct io_kiocb
*req
, unsigned int issue_flags
)
4269 return io_openat2(req
, issue_flags
);
4272 static int io_remove_buffers_prep(struct io_kiocb
*req
,
4273 const struct io_uring_sqe
*sqe
)
4275 struct io_provide_buf
*p
= &req
->pbuf
;
4278 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
||
4282 tmp
= READ_ONCE(sqe
->fd
);
4283 if (!tmp
|| tmp
> USHRT_MAX
)
4286 memset(p
, 0, sizeof(*p
));
4288 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4292 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
4293 int bgid
, unsigned nbufs
)
4297 /* shouldn't happen */
4301 /* the head kbuf is the list itself */
4302 while (!list_empty(&buf
->list
)) {
4303 struct io_buffer
*nxt
;
4305 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
4306 list_del(&nxt
->list
);
4313 xa_erase(&ctx
->io_buffers
, bgid
);
4318 static int io_remove_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
4320 struct io_provide_buf
*p
= &req
->pbuf
;
4321 struct io_ring_ctx
*ctx
= req
->ctx
;
4322 struct io_buffer
*head
;
4324 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4326 io_ring_submit_lock(ctx
, !force_nonblock
);
4328 lockdep_assert_held(&ctx
->uring_lock
);
4331 head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
4333 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
4337 /* complete before unlock, IOPOLL may need the lock */
4338 __io_req_complete(req
, issue_flags
, ret
, 0);
4339 io_ring_submit_unlock(ctx
, !force_nonblock
);
4343 static int io_provide_buffers_prep(struct io_kiocb
*req
,
4344 const struct io_uring_sqe
*sqe
)
4346 unsigned long size
, tmp_check
;
4347 struct io_provide_buf
*p
= &req
->pbuf
;
4350 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->splice_fd_in
)
4353 tmp
= READ_ONCE(sqe
->fd
);
4354 if (!tmp
|| tmp
> USHRT_MAX
)
4357 p
->addr
= READ_ONCE(sqe
->addr
);
4358 p
->len
= READ_ONCE(sqe
->len
);
4360 if (check_mul_overflow((unsigned long)p
->len
, (unsigned long)p
->nbufs
,
4363 if (check_add_overflow((unsigned long)p
->addr
, size
, &tmp_check
))
4366 size
= (unsigned long)p
->len
* p
->nbufs
;
4367 if (!access_ok(u64_to_user_ptr(p
->addr
), size
))
4370 p
->bgid
= READ_ONCE(sqe
->buf_group
);
4371 tmp
= READ_ONCE(sqe
->off
);
4372 if (tmp
> USHRT_MAX
)
4378 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
4380 struct io_buffer
*buf
;
4381 u64 addr
= pbuf
->addr
;
4382 int i
, bid
= pbuf
->bid
;
4384 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
4385 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL_ACCOUNT
);
4390 buf
->len
= min_t(__u32
, pbuf
->len
, MAX_RW_COUNT
);
4395 INIT_LIST_HEAD(&buf
->list
);
4398 list_add_tail(&buf
->list
, &(*head
)->list
);
4402 return i
? i
: -ENOMEM
;
4405 static int io_provide_buffers(struct io_kiocb
*req
, unsigned int issue_flags
)
4407 struct io_provide_buf
*p
= &req
->pbuf
;
4408 struct io_ring_ctx
*ctx
= req
->ctx
;
4409 struct io_buffer
*head
, *list
;
4411 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4413 io_ring_submit_lock(ctx
, !force_nonblock
);
4415 lockdep_assert_held(&ctx
->uring_lock
);
4417 list
= head
= xa_load(&ctx
->io_buffers
, p
->bgid
);
4419 ret
= io_add_buffers(p
, &head
);
4420 if (ret
>= 0 && !list
) {
4421 ret
= xa_insert(&ctx
->io_buffers
, p
->bgid
, head
, GFP_KERNEL
);
4423 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4427 /* complete before unlock, IOPOLL may need the lock */
4428 __io_req_complete(req
, issue_flags
, ret
, 0);
4429 io_ring_submit_unlock(ctx
, !force_nonblock
);
4433 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4434 const struct io_uring_sqe
*sqe
)
4436 #if defined(CONFIG_EPOLL)
4437 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
4439 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4442 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4443 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4444 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4446 if (ep_op_has_event(req
->epoll
.op
)) {
4447 struct epoll_event __user
*ev
;
4449 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4450 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4460 static int io_epoll_ctl(struct io_kiocb
*req
, unsigned int issue_flags
)
4462 #if defined(CONFIG_EPOLL)
4463 struct io_epoll
*ie
= &req
->epoll
;
4465 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4467 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4468 if (force_nonblock
&& ret
== -EAGAIN
)
4473 __io_req_complete(req
, issue_flags
, ret
, 0);
4480 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4482 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4483 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
|| sqe
->splice_fd_in
)
4485 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4488 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4489 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4490 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4497 static int io_madvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4499 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4500 struct io_madvise
*ma
= &req
->madvise
;
4503 if (issue_flags
& IO_URING_F_NONBLOCK
)
4506 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4509 io_req_complete(req
, ret
);
4516 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4518 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
|| sqe
->splice_fd_in
)
4520 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4523 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4524 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4525 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4529 static int io_fadvise(struct io_kiocb
*req
, unsigned int issue_flags
)
4531 struct io_fadvise
*fa
= &req
->fadvise
;
4534 if (issue_flags
& IO_URING_F_NONBLOCK
) {
4535 switch (fa
->advice
) {
4536 case POSIX_FADV_NORMAL
:
4537 case POSIX_FADV_RANDOM
:
4538 case POSIX_FADV_SEQUENTIAL
:
4545 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4548 __io_req_complete(req
, issue_flags
, ret
, 0);
4552 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4554 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4556 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
4558 if (req
->flags
& REQ_F_FIXED_FILE
)
4561 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4562 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4563 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4564 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4565 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4570 static int io_statx(struct io_kiocb
*req
, unsigned int issue_flags
)
4572 struct io_statx
*ctx
= &req
->statx
;
4575 if (issue_flags
& IO_URING_F_NONBLOCK
)
4578 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4583 io_req_complete(req
, ret
);
4587 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4589 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4591 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4592 sqe
->rw_flags
|| sqe
->buf_index
)
4594 if (req
->flags
& REQ_F_FIXED_FILE
)
4597 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4598 req
->close
.file_slot
= READ_ONCE(sqe
->file_index
);
4599 if (req
->close
.file_slot
&& req
->close
.fd
)
4605 static int io_close(struct io_kiocb
*req
, unsigned int issue_flags
)
4607 struct files_struct
*files
= current
->files
;
4608 struct io_close
*close
= &req
->close
;
4609 struct fdtable
*fdt
;
4610 struct file
*file
= NULL
;
4613 if (req
->close
.file_slot
) {
4614 ret
= io_close_fixed(req
, issue_flags
);
4618 spin_lock(&files
->file_lock
);
4619 fdt
= files_fdtable(files
);
4620 if (close
->fd
>= fdt
->max_fds
) {
4621 spin_unlock(&files
->file_lock
);
4624 file
= fdt
->fd
[close
->fd
];
4625 if (!file
|| file
->f_op
== &io_uring_fops
) {
4626 spin_unlock(&files
->file_lock
);
4631 /* if the file has a flush method, be safe and punt to async */
4632 if (file
->f_op
->flush
&& (issue_flags
& IO_URING_F_NONBLOCK
)) {
4633 spin_unlock(&files
->file_lock
);
4637 ret
= __close_fd_get_file(close
->fd
, &file
);
4638 spin_unlock(&files
->file_lock
);
4645 /* No ->flush() or already async, safely close from here */
4646 ret
= filp_close(file
, current
->files
);
4652 __io_req_complete(req
, issue_flags
, ret
, 0);
4656 static int io_sfr_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4658 struct io_ring_ctx
*ctx
= req
->ctx
;
4660 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4662 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
||
4666 req
->sync
.off
= READ_ONCE(sqe
->off
);
4667 req
->sync
.len
= READ_ONCE(sqe
->len
);
4668 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4672 static int io_sync_file_range(struct io_kiocb
*req
, unsigned int issue_flags
)
4676 /* sync_file_range always requires a blocking context */
4677 if (issue_flags
& IO_URING_F_NONBLOCK
)
4680 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4684 io_req_complete(req
, ret
);
4688 #if defined(CONFIG_NET)
4689 static int io_setup_async_msg(struct io_kiocb
*req
,
4690 struct io_async_msghdr
*kmsg
)
4692 struct io_async_msghdr
*async_msg
= req
->async_data
;
4696 if (io_alloc_async_data(req
)) {
4697 kfree(kmsg
->free_iov
);
4700 async_msg
= req
->async_data
;
4701 req
->flags
|= REQ_F_NEED_CLEANUP
;
4702 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4703 async_msg
->msg
.msg_name
= &async_msg
->addr
;
4704 /* if were using fast_iov, set it to the new one */
4705 if (!async_msg
->free_iov
)
4706 async_msg
->msg
.msg_iter
.iov
= async_msg
->fast_iov
;
4711 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4712 struct io_async_msghdr
*iomsg
)
4714 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4715 iomsg
->free_iov
= iomsg
->fast_iov
;
4716 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4717 req
->sr_msg
.msg_flags
, &iomsg
->free_iov
);
4720 static int io_sendmsg_prep_async(struct io_kiocb
*req
)
4724 ret
= io_sendmsg_copy_hdr(req
, req
->async_data
);
4726 req
->flags
|= REQ_F_NEED_CLEANUP
;
4730 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4732 struct io_sr_msg
*sr
= &req
->sr_msg
;
4734 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4737 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4738 sr
->len
= READ_ONCE(sqe
->len
);
4739 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
) | MSG_NOSIGNAL
;
4740 if (sr
->msg_flags
& MSG_DONTWAIT
)
4741 req
->flags
|= REQ_F_NOWAIT
;
4743 #ifdef CONFIG_COMPAT
4744 if (req
->ctx
->compat
)
4745 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4750 static int io_sendmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4752 struct io_async_msghdr iomsg
, *kmsg
;
4753 struct socket
*sock
;
4758 sock
= sock_from_file(req
->file
);
4759 if (unlikely(!sock
))
4762 kmsg
= req
->async_data
;
4764 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4770 flags
= req
->sr_msg
.msg_flags
;
4771 if (issue_flags
& IO_URING_F_NONBLOCK
)
4772 flags
|= MSG_DONTWAIT
;
4773 if (flags
& MSG_WAITALL
)
4774 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
4776 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4777 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4778 return io_setup_async_msg(req
, kmsg
);
4779 if (ret
== -ERESTARTSYS
)
4782 /* fast path, check for non-NULL to avoid function call */
4784 kfree(kmsg
->free_iov
);
4785 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4788 __io_req_complete(req
, issue_flags
, ret
, 0);
4792 static int io_send(struct io_kiocb
*req
, unsigned int issue_flags
)
4794 struct io_sr_msg
*sr
= &req
->sr_msg
;
4797 struct socket
*sock
;
4802 sock
= sock_from_file(req
->file
);
4803 if (unlikely(!sock
))
4806 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4810 msg
.msg_name
= NULL
;
4811 msg
.msg_control
= NULL
;
4812 msg
.msg_controllen
= 0;
4813 msg
.msg_namelen
= 0;
4815 flags
= req
->sr_msg
.msg_flags
;
4816 if (issue_flags
& IO_URING_F_NONBLOCK
)
4817 flags
|= MSG_DONTWAIT
;
4818 if (flags
& MSG_WAITALL
)
4819 min_ret
= iov_iter_count(&msg
.msg_iter
);
4821 msg
.msg_flags
= flags
;
4822 ret
= sock_sendmsg(sock
, &msg
);
4823 if ((issue_flags
& IO_URING_F_NONBLOCK
) && ret
== -EAGAIN
)
4825 if (ret
== -ERESTARTSYS
)
4830 __io_req_complete(req
, issue_flags
, ret
, 0);
4834 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4835 struct io_async_msghdr
*iomsg
)
4837 struct io_sr_msg
*sr
= &req
->sr_msg
;
4838 struct iovec __user
*uiov
;
4842 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4843 &iomsg
->uaddr
, &uiov
, &iov_len
);
4847 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4850 if (copy_from_user(iomsg
->fast_iov
, uiov
, sizeof(*uiov
)))
4852 sr
->len
= iomsg
->fast_iov
[0].iov_len
;
4853 iomsg
->free_iov
= NULL
;
4855 iomsg
->free_iov
= iomsg
->fast_iov
;
4856 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4857 &iomsg
->free_iov
, &iomsg
->msg
.msg_iter
,
4866 #ifdef CONFIG_COMPAT
4867 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4868 struct io_async_msghdr
*iomsg
)
4870 struct io_sr_msg
*sr
= &req
->sr_msg
;
4871 struct compat_iovec __user
*uiov
;
4876 ret
= __get_compat_msghdr(&iomsg
->msg
, sr
->umsg_compat
, &iomsg
->uaddr
,
4881 uiov
= compat_ptr(ptr
);
4882 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4883 compat_ssize_t clen
;
4887 if (!access_ok(uiov
, sizeof(*uiov
)))
4889 if (__get_user(clen
, &uiov
->iov_len
))
4894 iomsg
->free_iov
= NULL
;
4896 iomsg
->free_iov
= iomsg
->fast_iov
;
4897 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4898 UIO_FASTIOV
, &iomsg
->free_iov
,
4899 &iomsg
->msg
.msg_iter
, true);
4908 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4909 struct io_async_msghdr
*iomsg
)
4911 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4913 #ifdef CONFIG_COMPAT
4914 if (req
->ctx
->compat
)
4915 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4918 return __io_recvmsg_copy_hdr(req
, iomsg
);
4921 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4924 struct io_sr_msg
*sr
= &req
->sr_msg
;
4925 struct io_buffer
*kbuf
;
4927 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4932 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4936 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4938 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4941 static int io_recvmsg_prep_async(struct io_kiocb
*req
)
4945 ret
= io_recvmsg_copy_hdr(req
, req
->async_data
);
4947 req
->flags
|= REQ_F_NEED_CLEANUP
;
4951 static int io_recvmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4953 struct io_sr_msg
*sr
= &req
->sr_msg
;
4955 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4958 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4959 sr
->len
= READ_ONCE(sqe
->len
);
4960 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4961 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
) | MSG_NOSIGNAL
;
4962 if (sr
->msg_flags
& MSG_DONTWAIT
)
4963 req
->flags
|= REQ_F_NOWAIT
;
4965 #ifdef CONFIG_COMPAT
4966 if (req
->ctx
->compat
)
4967 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4972 static int io_recvmsg(struct io_kiocb
*req
, unsigned int issue_flags
)
4974 struct io_async_msghdr iomsg
, *kmsg
;
4975 struct socket
*sock
;
4976 struct io_buffer
*kbuf
;
4979 int ret
, cflags
= 0;
4980 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
4982 sock
= sock_from_file(req
->file
);
4983 if (unlikely(!sock
))
4986 kmsg
= req
->async_data
;
4988 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4994 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4995 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4997 return PTR_ERR(kbuf
);
4998 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4999 kmsg
->fast_iov
[0].iov_len
= req
->sr_msg
.len
;
5000 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->fast_iov
,
5001 1, req
->sr_msg
.len
);
5004 flags
= req
->sr_msg
.msg_flags
;
5006 flags
|= MSG_DONTWAIT
;
5007 if (flags
& MSG_WAITALL
)
5008 min_ret
= iov_iter_count(&kmsg
->msg
.msg_iter
);
5010 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
5011 kmsg
->uaddr
, flags
);
5012 if (force_nonblock
&& ret
== -EAGAIN
)
5013 return io_setup_async_msg(req
, kmsg
);
5014 if (ret
== -ERESTARTSYS
)
5017 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5018 cflags
= io_put_recv_kbuf(req
);
5019 /* fast path, check for non-NULL to avoid function call */
5021 kfree(kmsg
->free_iov
);
5022 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5023 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (kmsg
->msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
5025 __io_req_complete(req
, issue_flags
, ret
, cflags
);
5029 static int io_recv(struct io_kiocb
*req
, unsigned int issue_flags
)
5031 struct io_buffer
*kbuf
;
5032 struct io_sr_msg
*sr
= &req
->sr_msg
;
5034 void __user
*buf
= sr
->buf
;
5035 struct socket
*sock
;
5039 int ret
, cflags
= 0;
5040 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
5042 sock
= sock_from_file(req
->file
);
5043 if (unlikely(!sock
))
5046 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
5047 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
5049 return PTR_ERR(kbuf
);
5050 buf
= u64_to_user_ptr(kbuf
->addr
);
5053 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
5057 msg
.msg_name
= NULL
;
5058 msg
.msg_control
= NULL
;
5059 msg
.msg_controllen
= 0;
5060 msg
.msg_namelen
= 0;
5061 msg
.msg_iocb
= NULL
;
5064 flags
= req
->sr_msg
.msg_flags
;
5066 flags
|= MSG_DONTWAIT
;
5067 if (flags
& MSG_WAITALL
)
5068 min_ret
= iov_iter_count(&msg
.msg_iter
);
5070 ret
= sock_recvmsg(sock
, &msg
, flags
);
5071 if (force_nonblock
&& ret
== -EAGAIN
)
5073 if (ret
== -ERESTARTSYS
)
5076 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5077 cflags
= io_put_recv_kbuf(req
);
5078 if (ret
< min_ret
|| ((flags
& MSG_WAITALL
) && (msg
.msg_flags
& (MSG_TRUNC
| MSG_CTRUNC
))))
5080 __io_req_complete(req
, issue_flags
, ret
, cflags
);
5084 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5086 struct io_accept
*accept
= &req
->accept
;
5088 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5090 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
5093 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
5094 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
5095 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
5096 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
5098 accept
->file_slot
= READ_ONCE(sqe
->file_index
);
5099 if (accept
->file_slot
&& ((req
->open
.how
.flags
& O_CLOEXEC
) ||
5100 (accept
->flags
& SOCK_CLOEXEC
)))
5102 if (accept
->flags
& ~(SOCK_CLOEXEC
| SOCK_NONBLOCK
))
5104 if (SOCK_NONBLOCK
!= O_NONBLOCK
&& (accept
->flags
& SOCK_NONBLOCK
))
5105 accept
->flags
= (accept
->flags
& ~SOCK_NONBLOCK
) | O_NONBLOCK
;
5109 static int io_accept(struct io_kiocb
*req
, unsigned int issue_flags
)
5111 struct io_accept
*accept
= &req
->accept
;
5112 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
5113 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
5114 bool fixed
= !!accept
->file_slot
;
5118 if (req
->file
->f_flags
& O_NONBLOCK
)
5119 req
->flags
|= REQ_F_NOWAIT
;
5122 fd
= __get_unused_fd_flags(accept
->flags
, accept
->nofile
);
5123 if (unlikely(fd
< 0))
5126 file
= do_accept(req
->file
, file_flags
, accept
->addr
, accept
->addr_len
,
5131 ret
= PTR_ERR(file
);
5132 if (ret
== -EAGAIN
&& force_nonblock
)
5134 if (ret
== -ERESTARTSYS
)
5137 } else if (!fixed
) {
5138 fd_install(fd
, file
);
5141 ret
= io_install_fixed_file(req
, file
, issue_flags
,
5142 accept
->file_slot
- 1);
5144 __io_req_complete(req
, issue_flags
, ret
, 0);
5148 static int io_connect_prep_async(struct io_kiocb
*req
)
5150 struct io_async_connect
*io
= req
->async_data
;
5151 struct io_connect
*conn
= &req
->connect
;
5153 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
, &io
->address
);
5156 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5158 struct io_connect
*conn
= &req
->connect
;
5160 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5162 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
||
5166 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
5167 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
5171 static int io_connect(struct io_kiocb
*req
, unsigned int issue_flags
)
5173 struct io_async_connect __io
, *io
;
5174 unsigned file_flags
;
5176 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
5178 if (req
->async_data
) {
5179 io
= req
->async_data
;
5181 ret
= move_addr_to_kernel(req
->connect
.addr
,
5182 req
->connect
.addr_len
,
5189 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
5191 ret
= __sys_connect_file(req
->file
, &io
->address
,
5192 req
->connect
.addr_len
, file_flags
);
5193 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
5194 if (req
->async_data
)
5196 if (io_alloc_async_data(req
)) {
5200 memcpy(req
->async_data
, &__io
, sizeof(__io
));
5203 if (ret
== -ERESTARTSYS
)
5208 __io_req_complete(req
, issue_flags
, ret
, 0);
5211 #else /* !CONFIG_NET */
5212 #define IO_NETOP_FN(op) \
5213 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
5215 return -EOPNOTSUPP; \
5218 #define IO_NETOP_PREP(op) \
5220 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
5222 return -EOPNOTSUPP; \
5225 #define IO_NETOP_PREP_ASYNC(op) \
5227 static int io_##op##_prep_async(struct io_kiocb *req) \
5229 return -EOPNOTSUPP; \
5232 IO_NETOP_PREP_ASYNC(sendmsg
);
5233 IO_NETOP_PREP_ASYNC(recvmsg
);
5234 IO_NETOP_PREP_ASYNC(connect
);
5235 IO_NETOP_PREP(accept
);
5238 #endif /* CONFIG_NET */
5240 struct io_poll_table
{
5241 struct poll_table_struct pt
;
5242 struct io_kiocb
*req
;
5247 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
5248 __poll_t mask
, io_req_tw_func_t func
)
5250 /* for instances that support it check for an event match first: */
5251 if (mask
&& !(mask
& poll
->events
))
5254 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
5256 list_del_init(&poll
->wait
.entry
);
5259 req
->io_task_work
.func
= func
;
5262 * If this fails, then the task is exiting. When a task exits, the
5263 * work gets canceled, so just cancel this request as well instead
5264 * of executing it. We can't safely execute it anyway, as we may not
5265 * have the needed state needed for it anyway.
5267 io_req_task_work_add(req
);
5271 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
5272 __acquires(&req
->ctx
->completion_lock
)
5274 struct io_ring_ctx
*ctx
= req
->ctx
;
5276 /* req->task == current here, checking PF_EXITING is safe */
5277 if (unlikely(req
->task
->flags
& PF_EXITING
))
5278 WRITE_ONCE(poll
->canceled
, true);
5280 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5281 struct poll_table_struct pt
= { ._key
= poll
->events
};
5283 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
5286 spin_lock(&ctx
->completion_lock
);
5287 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
5288 add_wait_queue(poll
->head
, &poll
->wait
);
5295 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
5297 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
5298 if (req
->opcode
== IORING_OP_POLL_ADD
)
5299 return req
->async_data
;
5300 return req
->apoll
->double_poll
;
5303 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
5305 if (req
->opcode
== IORING_OP_POLL_ADD
)
5307 return &req
->apoll
->poll
;
5310 static void io_poll_remove_double(struct io_kiocb
*req
)
5311 __must_hold(&req
->ctx
->completion_lock
)
5313 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
5315 lockdep_assert_held(&req
->ctx
->completion_lock
);
5317 if (poll
&& poll
->head
) {
5318 struct wait_queue_head
*head
= poll
->head
;
5320 spin_lock_irq(&head
->lock
);
5321 list_del_init(&poll
->wait
.entry
);
5322 if (poll
->wait
.private)
5325 spin_unlock_irq(&head
->lock
);
5329 static bool __io_poll_complete(struct io_kiocb
*req
, __poll_t mask
)
5330 __must_hold(&req
->ctx
->completion_lock
)
5332 struct io_ring_ctx
*ctx
= req
->ctx
;
5333 unsigned flags
= IORING_CQE_F_MORE
;
5336 if (READ_ONCE(req
->poll
.canceled
)) {
5338 req
->poll
.events
|= EPOLLONESHOT
;
5340 error
= mangle_poll(mask
);
5342 if (req
->poll
.events
& EPOLLONESHOT
)
5344 if (!io_cqring_fill_event(ctx
, req
->user_data
, error
, flags
)) {
5345 req
->poll
.events
|= EPOLLONESHOT
;
5348 if (flags
& IORING_CQE_F_MORE
)
5351 return !(flags
& IORING_CQE_F_MORE
);
5354 static inline bool io_poll_complete(struct io_kiocb
*req
, __poll_t mask
)
5355 __must_hold(&req
->ctx
->completion_lock
)
5359 done
= __io_poll_complete(req
, mask
);
5360 io_commit_cqring(req
->ctx
);
5364 static void io_poll_task_func(struct io_kiocb
*req
, bool *locked
)
5366 struct io_ring_ctx
*ctx
= req
->ctx
;
5367 struct io_kiocb
*nxt
;
5369 if (io_poll_rewait(req
, &req
->poll
)) {
5370 spin_unlock(&ctx
->completion_lock
);
5374 if (req
->poll
.done
) {
5375 spin_unlock(&ctx
->completion_lock
);
5378 done
= __io_poll_complete(req
, req
->result
);
5380 io_poll_remove_double(req
);
5381 hash_del(&req
->hash_node
);
5382 req
->poll
.done
= true;
5385 add_wait_queue(req
->poll
.head
, &req
->poll
.wait
);
5387 io_commit_cqring(ctx
);
5388 spin_unlock(&ctx
->completion_lock
);
5389 io_cqring_ev_posted(ctx
);
5392 nxt
= io_put_req_find_next(req
);
5394 io_req_task_submit(nxt
, locked
);
5399 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
5400 int sync
, void *key
)
5402 struct io_kiocb
*req
= wait
->private;
5403 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
5404 __poll_t mask
= key_to_poll(key
);
5405 unsigned long flags
;
5407 /* for instances that support it check for an event match first: */
5408 if (mask
&& !(mask
& poll
->events
))
5410 if (!(poll
->events
& EPOLLONESHOT
))
5411 return poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5413 list_del_init(&wait
->entry
);
5418 spin_lock_irqsave(&poll
->head
->lock
, flags
);
5419 done
= list_empty(&poll
->wait
.entry
);
5421 list_del_init(&poll
->wait
.entry
);
5422 /* make sure double remove sees this as being gone */
5423 wait
->private = NULL
;
5424 spin_unlock_irqrestore(&poll
->head
->lock
, flags
);
5426 /* use wait func handler, so it matches the rq type */
5427 poll
->wait
.func(&poll
->wait
, mode
, sync
, key
);
5434 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
5435 wait_queue_func_t wake_func
)
5439 poll
->canceled
= false;
5440 #define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
5441 /* mask in events that we always want/need */
5442 poll
->events
= events
| IO_POLL_UNMASK
;
5443 INIT_LIST_HEAD(&poll
->wait
.entry
);
5444 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5447 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5448 struct wait_queue_head
*head
,
5449 struct io_poll_iocb
**poll_ptr
)
5451 struct io_kiocb
*req
= pt
->req
;
5454 * The file being polled uses multiple waitqueues for poll handling
5455 * (e.g. one for read, one for write). Setup a separate io_poll_iocb
5458 if (unlikely(pt
->nr_entries
)) {
5459 struct io_poll_iocb
*poll_one
= poll
;
5461 /* double add on the same waitqueue head, ignore */
5462 if (poll_one
->head
== head
)
5464 /* already have a 2nd entry, fail a third attempt */
5466 if ((*poll_ptr
)->head
== head
)
5468 pt
->error
= -EINVAL
;
5472 * Can't handle multishot for double wait for now, turn it
5473 * into one-shot mode.
5475 if (!(poll_one
->events
& EPOLLONESHOT
))
5476 poll_one
->events
|= EPOLLONESHOT
;
5477 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5479 pt
->error
= -ENOMEM
;
5482 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5484 poll
->wait
.private = req
;
5491 if (poll
->events
& EPOLLEXCLUSIVE
)
5492 add_wait_queue_exclusive(head
, &poll
->wait
);
5494 add_wait_queue(head
, &poll
->wait
);
5497 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5498 struct poll_table_struct
*p
)
5500 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5501 struct async_poll
*apoll
= pt
->req
->apoll
;
5503 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5506 static void io_async_task_func(struct io_kiocb
*req
, bool *locked
)
5508 struct async_poll
*apoll
= req
->apoll
;
5509 struct io_ring_ctx
*ctx
= req
->ctx
;
5511 trace_io_uring_task_run(req
->ctx
, req
, req
->opcode
, req
->user_data
);
5513 if (io_poll_rewait(req
, &apoll
->poll
)) {
5514 spin_unlock(&ctx
->completion_lock
);
5518 hash_del(&req
->hash_node
);
5519 io_poll_remove_double(req
);
5520 apoll
->poll
.done
= true;
5521 spin_unlock(&ctx
->completion_lock
);
5523 if (!READ_ONCE(apoll
->poll
.canceled
))
5524 io_req_task_submit(req
, locked
);
5526 io_req_complete_failed(req
, -ECANCELED
);
5529 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5532 struct io_kiocb
*req
= wait
->private;
5533 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5535 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5538 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5541 static void io_poll_req_insert(struct io_kiocb
*req
)
5543 struct io_ring_ctx
*ctx
= req
->ctx
;
5544 struct hlist_head
*list
;
5546 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5547 hlist_add_head(&req
->hash_node
, list
);
5550 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5551 struct io_poll_iocb
*poll
,
5552 struct io_poll_table
*ipt
, __poll_t mask
,
5553 wait_queue_func_t wake_func
)
5554 __acquires(&ctx
->completion_lock
)
5556 struct io_ring_ctx
*ctx
= req
->ctx
;
5557 bool cancel
= false;
5559 INIT_HLIST_NODE(&req
->hash_node
);
5560 io_init_poll_iocb(poll
, mask
, wake_func
);
5561 poll
->file
= req
->file
;
5562 poll
->wait
.private = req
;
5564 ipt
->pt
._key
= mask
;
5567 ipt
->nr_entries
= 0;
5569 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5570 if (unlikely(!ipt
->nr_entries
) && !ipt
->error
)
5571 ipt
->error
= -EINVAL
;
5573 spin_lock(&ctx
->completion_lock
);
5574 if (ipt
->error
|| (mask
&& (poll
->events
& EPOLLONESHOT
)))
5575 io_poll_remove_double(req
);
5576 if (likely(poll
->head
)) {
5577 spin_lock_irq(&poll
->head
->lock
);
5578 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5584 if ((mask
&& (poll
->events
& EPOLLONESHOT
)) || ipt
->error
)
5585 list_del_init(&poll
->wait
.entry
);
5587 WRITE_ONCE(poll
->canceled
, true);
5588 else if (!poll
->done
) /* actually waiting for an event */
5589 io_poll_req_insert(req
);
5590 spin_unlock_irq(&poll
->head
->lock
);
5602 static int io_arm_poll_handler(struct io_kiocb
*req
)
5604 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5605 struct io_ring_ctx
*ctx
= req
->ctx
;
5606 struct async_poll
*apoll
;
5607 struct io_poll_table ipt
;
5608 __poll_t ret
, mask
= EPOLLONESHOT
| POLLERR
| POLLPRI
;
5611 if (!req
->file
|| !file_can_poll(req
->file
))
5612 return IO_APOLL_ABORTED
;
5613 if (req
->flags
& REQ_F_POLLED
)
5614 return IO_APOLL_ABORTED
;
5615 if (!def
->pollin
&& !def
->pollout
)
5616 return IO_APOLL_ABORTED
;
5620 mask
|= POLLIN
| POLLRDNORM
;
5622 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5623 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5624 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5628 mask
|= POLLOUT
| POLLWRNORM
;
5631 /* if we can't nonblock try, then no point in arming a poll handler */
5632 if (!io_file_supports_nowait(req
, rw
))
5633 return IO_APOLL_ABORTED
;
5635 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5636 if (unlikely(!apoll
))
5637 return IO_APOLL_ABORTED
;
5638 apoll
->double_poll
= NULL
;
5640 req
->flags
|= REQ_F_POLLED
;
5641 ipt
.pt
._qproc
= io_async_queue_proc
;
5642 io_req_set_refcount(req
);
5644 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5646 spin_unlock(&ctx
->completion_lock
);
5647 if (ret
|| ipt
.error
)
5648 return ret
? IO_APOLL_READY
: IO_APOLL_ABORTED
;
5650 trace_io_uring_poll_arm(ctx
, req
, req
->opcode
, req
->user_data
,
5651 mask
, apoll
->poll
.events
);
5655 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5656 struct io_poll_iocb
*poll
, bool do_cancel
)
5657 __must_hold(&req
->ctx
->completion_lock
)
5659 bool do_complete
= false;
5663 spin_lock_irq(&poll
->head
->lock
);
5665 WRITE_ONCE(poll
->canceled
, true);
5666 if (!list_empty(&poll
->wait
.entry
)) {
5667 list_del_init(&poll
->wait
.entry
);
5670 spin_unlock_irq(&poll
->head
->lock
);
5671 hash_del(&req
->hash_node
);
5675 static bool io_poll_remove_one(struct io_kiocb
*req
)
5676 __must_hold(&req
->ctx
->completion_lock
)
5680 io_poll_remove_double(req
);
5681 do_complete
= __io_poll_remove_one(req
, io_poll_get_single(req
), true);
5684 io_cqring_fill_event(req
->ctx
, req
->user_data
, -ECANCELED
, 0);
5685 io_commit_cqring(req
->ctx
);
5687 io_put_req_deferred(req
);
5693 * Returns true if we found and killed one or more poll requests
5695 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
5698 struct hlist_node
*tmp
;
5699 struct io_kiocb
*req
;
5702 spin_lock(&ctx
->completion_lock
);
5703 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5704 struct hlist_head
*list
;
5706 list
= &ctx
->cancel_hash
[i
];
5707 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5708 if (io_match_task(req
, tsk
, cancel_all
))
5709 posted
+= io_poll_remove_one(req
);
5712 spin_unlock(&ctx
->completion_lock
);
5715 io_cqring_ev_posted(ctx
);
5720 static struct io_kiocb
*io_poll_find(struct io_ring_ctx
*ctx
, __u64 sqe_addr
,
5722 __must_hold(&ctx
->completion_lock
)
5724 struct hlist_head
*list
;
5725 struct io_kiocb
*req
;
5727 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5728 hlist_for_each_entry(req
, list
, hash_node
) {
5729 if (sqe_addr
!= req
->user_data
)
5731 if (poll_only
&& req
->opcode
!= IORING_OP_POLL_ADD
)
5738 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
,
5740 __must_hold(&ctx
->completion_lock
)
5742 struct io_kiocb
*req
;
5744 req
= io_poll_find(ctx
, sqe_addr
, poll_only
);
5747 if (io_poll_remove_one(req
))
5753 static __poll_t
io_poll_parse_events(const struct io_uring_sqe
*sqe
,
5758 events
= READ_ONCE(sqe
->poll32_events
);
5760 events
= swahw32(events
);
5762 if (!(flags
& IORING_POLL_ADD_MULTI
))
5763 events
|= EPOLLONESHOT
;
5764 return demangle_poll(events
) | (events
& (EPOLLEXCLUSIVE
|EPOLLONESHOT
));
5767 static int io_poll_update_prep(struct io_kiocb
*req
,
5768 const struct io_uring_sqe
*sqe
)
5770 struct io_poll_update
*upd
= &req
->poll_update
;
5773 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5775 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->splice_fd_in
)
5777 flags
= READ_ONCE(sqe
->len
);
5778 if (flags
& ~(IORING_POLL_UPDATE_EVENTS
| IORING_POLL_UPDATE_USER_DATA
|
5779 IORING_POLL_ADD_MULTI
))
5781 /* meaningless without update */
5782 if (flags
== IORING_POLL_ADD_MULTI
)
5785 upd
->old_user_data
= READ_ONCE(sqe
->addr
);
5786 upd
->update_events
= flags
& IORING_POLL_UPDATE_EVENTS
;
5787 upd
->update_user_data
= flags
& IORING_POLL_UPDATE_USER_DATA
;
5789 upd
->new_user_data
= READ_ONCE(sqe
->off
);
5790 if (!upd
->update_user_data
&& upd
->new_user_data
)
5792 if (upd
->update_events
)
5793 upd
->events
= io_poll_parse_events(sqe
, flags
);
5794 else if (sqe
->poll32_events
)
5800 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5803 struct io_kiocb
*req
= wait
->private;
5804 struct io_poll_iocb
*poll
= &req
->poll
;
5806 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5809 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5810 struct poll_table_struct
*p
)
5812 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5814 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5817 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5819 struct io_poll_iocb
*poll
= &req
->poll
;
5822 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5824 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
|| sqe
->addr
)
5826 flags
= READ_ONCE(sqe
->len
);
5827 if (flags
& ~IORING_POLL_ADD_MULTI
)
5830 io_req_set_refcount(req
);
5831 poll
->events
= io_poll_parse_events(sqe
, flags
);
5835 static int io_poll_add(struct io_kiocb
*req
, unsigned int issue_flags
)
5837 struct io_poll_iocb
*poll
= &req
->poll
;
5838 struct io_ring_ctx
*ctx
= req
->ctx
;
5839 struct io_poll_table ipt
;
5843 ipt
.pt
._qproc
= io_poll_queue_proc
;
5845 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5848 if (mask
) { /* no async, we'd stolen it */
5850 done
= io_poll_complete(req
, mask
);
5852 spin_unlock(&ctx
->completion_lock
);
5855 io_cqring_ev_posted(ctx
);
5862 static int io_poll_update(struct io_kiocb
*req
, unsigned int issue_flags
)
5864 struct io_ring_ctx
*ctx
= req
->ctx
;
5865 struct io_kiocb
*preq
;
5869 spin_lock(&ctx
->completion_lock
);
5870 preq
= io_poll_find(ctx
, req
->poll_update
.old_user_data
, true);
5876 if (!req
->poll_update
.update_events
&& !req
->poll_update
.update_user_data
) {
5878 ret
= io_poll_remove_one(preq
) ? 0 : -EALREADY
;
5883 * Don't allow racy completion with singleshot, as we cannot safely
5884 * update those. For multishot, if we're racing with completion, just
5885 * let completion re-add it.
5887 completing
= !__io_poll_remove_one(preq
, &preq
->poll
, false);
5888 if (completing
&& (preq
->poll
.events
& EPOLLONESHOT
)) {
5892 /* we now have a detached poll request. reissue. */
5896 spin_unlock(&ctx
->completion_lock
);
5898 io_req_complete(req
, ret
);
5901 /* only mask one event flags, keep behavior flags */
5902 if (req
->poll_update
.update_events
) {
5903 preq
->poll
.events
&= ~0xffff;
5904 preq
->poll
.events
|= req
->poll_update
.events
& 0xffff;
5905 preq
->poll
.events
|= IO_POLL_UNMASK
;
5907 if (req
->poll_update
.update_user_data
)
5908 preq
->user_data
= req
->poll_update
.new_user_data
;
5909 spin_unlock(&ctx
->completion_lock
);
5911 /* complete update request, we're done with it */
5912 io_req_complete(req
, ret
);
5915 ret
= io_poll_add(preq
, issue_flags
);
5918 io_req_complete(preq
, ret
);
5924 static void io_req_task_timeout(struct io_kiocb
*req
, bool *locked
)
5927 io_req_complete_post(req
, -ETIME
, 0);
5930 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5932 struct io_timeout_data
*data
= container_of(timer
,
5933 struct io_timeout_data
, timer
);
5934 struct io_kiocb
*req
= data
->req
;
5935 struct io_ring_ctx
*ctx
= req
->ctx
;
5936 unsigned long flags
;
5938 spin_lock_irqsave(&ctx
->timeout_lock
, flags
);
5939 list_del_init(&req
->timeout
.list
);
5940 atomic_set(&req
->ctx
->cq_timeouts
,
5941 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5942 spin_unlock_irqrestore(&ctx
->timeout_lock
, flags
);
5944 req
->io_task_work
.func
= io_req_task_timeout
;
5945 io_req_task_work_add(req
);
5946 return HRTIMER_NORESTART
;
5949 static struct io_kiocb
*io_timeout_extract(struct io_ring_ctx
*ctx
,
5951 __must_hold(&ctx
->timeout_lock
)
5953 struct io_timeout_data
*io
;
5954 struct io_kiocb
*req
;
5957 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5958 found
= user_data
== req
->user_data
;
5963 return ERR_PTR(-ENOENT
);
5965 io
= req
->async_data
;
5966 if (hrtimer_try_to_cancel(&io
->timer
) == -1)
5967 return ERR_PTR(-EALREADY
);
5968 list_del_init(&req
->timeout
.list
);
5972 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5973 __must_hold(&ctx
->completion_lock
)
5974 __must_hold(&ctx
->timeout_lock
)
5976 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
5979 return PTR_ERR(req
);
5982 io_cqring_fill_event(ctx
, req
->user_data
, -ECANCELED
, 0);
5983 io_put_req_deferred(req
);
5987 static clockid_t
io_timeout_get_clock(struct io_timeout_data
*data
)
5989 switch (data
->flags
& IORING_TIMEOUT_CLOCK_MASK
) {
5990 case IORING_TIMEOUT_BOOTTIME
:
5991 return CLOCK_BOOTTIME
;
5992 case IORING_TIMEOUT_REALTIME
:
5993 return CLOCK_REALTIME
;
5995 /* can't happen, vetted at prep time */
5999 return CLOCK_MONOTONIC
;
6003 static int io_linked_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
6004 struct timespec64
*ts
, enum hrtimer_mode mode
)
6005 __must_hold(&ctx
->timeout_lock
)
6007 struct io_timeout_data
*io
;
6008 struct io_kiocb
*req
;
6011 list_for_each_entry(req
, &ctx
->ltimeout_list
, timeout
.list
) {
6012 found
= user_data
== req
->user_data
;
6019 io
= req
->async_data
;
6020 if (hrtimer_try_to_cancel(&io
->timer
) == -1)
6022 hrtimer_init(&io
->timer
, io_timeout_get_clock(io
), mode
);
6023 io
->timer
.function
= io_link_timeout_fn
;
6024 hrtimer_start(&io
->timer
, timespec64_to_ktime(*ts
), mode
);
6028 static int io_timeout_update(struct io_ring_ctx
*ctx
, __u64 user_data
,
6029 struct timespec64
*ts
, enum hrtimer_mode mode
)
6030 __must_hold(&ctx
->timeout_lock
)
6032 struct io_kiocb
*req
= io_timeout_extract(ctx
, user_data
);
6033 struct io_timeout_data
*data
;
6036 return PTR_ERR(req
);
6038 req
->timeout
.off
= 0; /* noseq */
6039 data
= req
->async_data
;
6040 list_add_tail(&req
->timeout
.list
, &ctx
->timeout_list
);
6041 hrtimer_init(&data
->timer
, io_timeout_get_clock(data
), mode
);
6042 data
->timer
.function
= io_timeout_fn
;
6043 hrtimer_start(&data
->timer
, timespec64_to_ktime(*ts
), mode
);
6047 static int io_timeout_remove_prep(struct io_kiocb
*req
,
6048 const struct io_uring_sqe
*sqe
)
6050 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
6052 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
6054 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
6056 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
|| sqe
->splice_fd_in
)
6059 tr
->ltimeout
= false;
6060 tr
->addr
= READ_ONCE(sqe
->addr
);
6061 tr
->flags
= READ_ONCE(sqe
->timeout_flags
);
6062 if (tr
->flags
& IORING_TIMEOUT_UPDATE_MASK
) {
6063 if (hweight32(tr
->flags
& IORING_TIMEOUT_CLOCK_MASK
) > 1)
6065 if (tr
->flags
& IORING_LINK_TIMEOUT_UPDATE
)
6066 tr
->ltimeout
= true;
6067 if (tr
->flags
& ~(IORING_TIMEOUT_UPDATE_MASK
|IORING_TIMEOUT_ABS
))
6069 if (get_timespec64(&tr
->ts
, u64_to_user_ptr(sqe
->addr2
)))
6071 } else if (tr
->flags
) {
6072 /* timeout removal doesn't support flags */
6079 static inline enum hrtimer_mode
io_translate_timeout_mode(unsigned int flags
)
6081 return (flags
& IORING_TIMEOUT_ABS
) ? HRTIMER_MODE_ABS
6086 * Remove or update an existing timeout command
6088 static int io_timeout_remove(struct io_kiocb
*req
, unsigned int issue_flags
)
6090 struct io_timeout_rem
*tr
= &req
->timeout_rem
;
6091 struct io_ring_ctx
*ctx
= req
->ctx
;
6094 if (!(req
->timeout_rem
.flags
& IORING_TIMEOUT_UPDATE
)) {
6095 spin_lock(&ctx
->completion_lock
);
6096 spin_lock_irq(&ctx
->timeout_lock
);
6097 ret
= io_timeout_cancel(ctx
, tr
->addr
);
6098 spin_unlock_irq(&ctx
->timeout_lock
);
6099 spin_unlock(&ctx
->completion_lock
);
6101 enum hrtimer_mode mode
= io_translate_timeout_mode(tr
->flags
);
6103 spin_lock_irq(&ctx
->timeout_lock
);
6105 ret
= io_linked_timeout_update(ctx
, tr
->addr
, &tr
->ts
, mode
);
6107 ret
= io_timeout_update(ctx
, tr
->addr
, &tr
->ts
, mode
);
6108 spin_unlock_irq(&ctx
->timeout_lock
);
6113 io_req_complete_post(req
, ret
, 0);
6117 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6118 bool is_timeout_link
)
6120 struct io_timeout_data
*data
;
6122 u32 off
= READ_ONCE(sqe
->off
);
6124 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
6126 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1 ||
6129 if (off
&& is_timeout_link
)
6131 flags
= READ_ONCE(sqe
->timeout_flags
);
6132 if (flags
& ~(IORING_TIMEOUT_ABS
| IORING_TIMEOUT_CLOCK_MASK
))
6134 /* more than one clock specified is invalid, obviously */
6135 if (hweight32(flags
& IORING_TIMEOUT_CLOCK_MASK
) > 1)
6138 INIT_LIST_HEAD(&req
->timeout
.list
);
6139 req
->timeout
.off
= off
;
6140 if (unlikely(off
&& !req
->ctx
->off_timeout_used
))
6141 req
->ctx
->off_timeout_used
= true;
6143 if (!req
->async_data
&& io_alloc_async_data(req
))
6146 data
= req
->async_data
;
6148 data
->flags
= flags
;
6150 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
6153 data
->mode
= io_translate_timeout_mode(flags
);
6154 hrtimer_init(&data
->timer
, io_timeout_get_clock(data
), data
->mode
);
6156 if (is_timeout_link
) {
6157 struct io_submit_link
*link
= &req
->ctx
->submit_state
.link
;
6161 if (link
->last
->opcode
== IORING_OP_LINK_TIMEOUT
)
6163 req
->timeout
.head
= link
->last
;
6164 link
->last
->flags
|= REQ_F_ARM_LTIMEOUT
;
6169 static int io_timeout(struct io_kiocb
*req
, unsigned int issue_flags
)
6171 struct io_ring_ctx
*ctx
= req
->ctx
;
6172 struct io_timeout_data
*data
= req
->async_data
;
6173 struct list_head
*entry
;
6174 u32 tail
, off
= req
->timeout
.off
;
6176 spin_lock_irq(&ctx
->timeout_lock
);
6179 * sqe->off holds how many events that need to occur for this
6180 * timeout event to be satisfied. If it isn't set, then this is
6181 * a pure timeout request, sequence isn't used.
6183 if (io_is_timeout_noseq(req
)) {
6184 entry
= ctx
->timeout_list
.prev
;
6188 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
6189 req
->timeout
.target_seq
= tail
+ off
;
6191 /* Update the last seq here in case io_flush_timeouts() hasn't.
6192 * This is safe because ->completion_lock is held, and submissions
6193 * and completions are never mixed in the same ->completion_lock section.
6195 ctx
->cq_last_tm_flush
= tail
;
6198 * Insertion sort, ensuring the first entry in the list is always
6199 * the one we need first.
6201 list_for_each_prev(entry
, &ctx
->timeout_list
) {
6202 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
6205 if (io_is_timeout_noseq(nxt
))
6207 /* nxt.seq is behind @tail, otherwise would've been completed */
6208 if (off
>= nxt
->timeout
.target_seq
- tail
)
6212 list_add(&req
->timeout
.list
, entry
);
6213 data
->timer
.function
= io_timeout_fn
;
6214 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
6215 spin_unlock_irq(&ctx
->timeout_lock
);
6219 struct io_cancel_data
{
6220 struct io_ring_ctx
*ctx
;
6224 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
6226 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6227 struct io_cancel_data
*cd
= data
;
6229 return req
->ctx
== cd
->ctx
&& req
->user_data
== cd
->user_data
;
6232 static int io_async_cancel_one(struct io_uring_task
*tctx
, u64 user_data
,
6233 struct io_ring_ctx
*ctx
)
6235 struct io_cancel_data data
= { .ctx
= ctx
, .user_data
= user_data
, };
6236 enum io_wq_cancel cancel_ret
;
6239 if (!tctx
|| !tctx
->io_wq
)
6242 cancel_ret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_cb
, &data
, false);
6243 switch (cancel_ret
) {
6244 case IO_WQ_CANCEL_OK
:
6247 case IO_WQ_CANCEL_RUNNING
:
6250 case IO_WQ_CANCEL_NOTFOUND
:
6258 static int io_try_cancel_userdata(struct io_kiocb
*req
, u64 sqe_addr
)
6260 struct io_ring_ctx
*ctx
= req
->ctx
;
6263 WARN_ON_ONCE(!io_wq_current_is_worker() && req
->task
!= current
);
6265 ret
= io_async_cancel_one(req
->task
->io_uring
, sqe_addr
, ctx
);
6269 spin_lock(&ctx
->completion_lock
);
6270 spin_lock_irq(&ctx
->timeout_lock
);
6271 ret
= io_timeout_cancel(ctx
, sqe_addr
);
6272 spin_unlock_irq(&ctx
->timeout_lock
);
6275 ret
= io_poll_cancel(ctx
, sqe_addr
, false);
6277 spin_unlock(&ctx
->completion_lock
);
6281 static int io_async_cancel_prep(struct io_kiocb
*req
,
6282 const struct io_uring_sqe
*sqe
)
6284 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
6286 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
6288 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
||
6292 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
6296 static int io_async_cancel(struct io_kiocb
*req
, unsigned int issue_flags
)
6298 struct io_ring_ctx
*ctx
= req
->ctx
;
6299 u64 sqe_addr
= req
->cancel
.addr
;
6300 struct io_tctx_node
*node
;
6303 ret
= io_try_cancel_userdata(req
, sqe_addr
);
6307 /* slow path, try all io-wq's */
6308 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
6310 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
6311 struct io_uring_task
*tctx
= node
->task
->io_uring
;
6313 ret
= io_async_cancel_one(tctx
, req
->cancel
.addr
, ctx
);
6317 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
6321 io_req_complete_post(req
, ret
, 0);
6325 static int io_rsrc_update_prep(struct io_kiocb
*req
,
6326 const struct io_uring_sqe
*sqe
)
6328 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
6330 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->splice_fd_in
)
6333 req
->rsrc_update
.offset
= READ_ONCE(sqe
->off
);
6334 req
->rsrc_update
.nr_args
= READ_ONCE(sqe
->len
);
6335 if (!req
->rsrc_update
.nr_args
)
6337 req
->rsrc_update
.arg
= READ_ONCE(sqe
->addr
);
6341 static int io_files_update(struct io_kiocb
*req
, unsigned int issue_flags
)
6343 struct io_ring_ctx
*ctx
= req
->ctx
;
6344 struct io_uring_rsrc_update2 up
;
6347 up
.offset
= req
->rsrc_update
.offset
;
6348 up
.data
= req
->rsrc_update
.arg
;
6353 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
6354 ret
= __io_register_rsrc_update(ctx
, IORING_RSRC_FILE
,
6355 &up
, req
->rsrc_update
.nr_args
);
6356 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
6360 __io_req_complete(req
, issue_flags
, ret
, 0);
6364 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
6366 switch (req
->opcode
) {
6369 case IORING_OP_READV
:
6370 case IORING_OP_READ_FIXED
:
6371 case IORING_OP_READ
:
6372 return io_read_prep(req
, sqe
);
6373 case IORING_OP_WRITEV
:
6374 case IORING_OP_WRITE_FIXED
:
6375 case IORING_OP_WRITE
:
6376 return io_write_prep(req
, sqe
);
6377 case IORING_OP_POLL_ADD
:
6378 return io_poll_add_prep(req
, sqe
);
6379 case IORING_OP_POLL_REMOVE
:
6380 return io_poll_update_prep(req
, sqe
);
6381 case IORING_OP_FSYNC
:
6382 return io_fsync_prep(req
, sqe
);
6383 case IORING_OP_SYNC_FILE_RANGE
:
6384 return io_sfr_prep(req
, sqe
);
6385 case IORING_OP_SENDMSG
:
6386 case IORING_OP_SEND
:
6387 return io_sendmsg_prep(req
, sqe
);
6388 case IORING_OP_RECVMSG
:
6389 case IORING_OP_RECV
:
6390 return io_recvmsg_prep(req
, sqe
);
6391 case IORING_OP_CONNECT
:
6392 return io_connect_prep(req
, sqe
);
6393 case IORING_OP_TIMEOUT
:
6394 return io_timeout_prep(req
, sqe
, false);
6395 case IORING_OP_TIMEOUT_REMOVE
:
6396 return io_timeout_remove_prep(req
, sqe
);
6397 case IORING_OP_ASYNC_CANCEL
:
6398 return io_async_cancel_prep(req
, sqe
);
6399 case IORING_OP_LINK_TIMEOUT
:
6400 return io_timeout_prep(req
, sqe
, true);
6401 case IORING_OP_ACCEPT
:
6402 return io_accept_prep(req
, sqe
);
6403 case IORING_OP_FALLOCATE
:
6404 return io_fallocate_prep(req
, sqe
);
6405 case IORING_OP_OPENAT
:
6406 return io_openat_prep(req
, sqe
);
6407 case IORING_OP_CLOSE
:
6408 return io_close_prep(req
, sqe
);
6409 case IORING_OP_FILES_UPDATE
:
6410 return io_rsrc_update_prep(req
, sqe
);
6411 case IORING_OP_STATX
:
6412 return io_statx_prep(req
, sqe
);
6413 case IORING_OP_FADVISE
:
6414 return io_fadvise_prep(req
, sqe
);
6415 case IORING_OP_MADVISE
:
6416 return io_madvise_prep(req
, sqe
);
6417 case IORING_OP_OPENAT2
:
6418 return io_openat2_prep(req
, sqe
);
6419 case IORING_OP_EPOLL_CTL
:
6420 return io_epoll_ctl_prep(req
, sqe
);
6421 case IORING_OP_SPLICE
:
6422 return io_splice_prep(req
, sqe
);
6423 case IORING_OP_PROVIDE_BUFFERS
:
6424 return io_provide_buffers_prep(req
, sqe
);
6425 case IORING_OP_REMOVE_BUFFERS
:
6426 return io_remove_buffers_prep(req
, sqe
);
6428 return io_tee_prep(req
, sqe
);
6429 case IORING_OP_SHUTDOWN
:
6430 return io_shutdown_prep(req
, sqe
);
6431 case IORING_OP_RENAMEAT
:
6432 return io_renameat_prep(req
, sqe
);
6433 case IORING_OP_UNLINKAT
:
6434 return io_unlinkat_prep(req
, sqe
);
6435 case IORING_OP_MKDIRAT
:
6436 return io_mkdirat_prep(req
, sqe
);
6437 case IORING_OP_SYMLINKAT
:
6438 return io_symlinkat_prep(req
, sqe
);
6439 case IORING_OP_LINKAT
:
6440 return io_linkat_prep(req
, sqe
);
6443 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
6448 static int io_req_prep_async(struct io_kiocb
*req
)
6450 if (!io_op_defs
[req
->opcode
].needs_async_setup
)
6452 if (WARN_ON_ONCE(req
->async_data
))
6454 if (io_alloc_async_data(req
))
6457 switch (req
->opcode
) {
6458 case IORING_OP_READV
:
6459 return io_rw_prep_async(req
, READ
);
6460 case IORING_OP_WRITEV
:
6461 return io_rw_prep_async(req
, WRITE
);
6462 case IORING_OP_SENDMSG
:
6463 return io_sendmsg_prep_async(req
);
6464 case IORING_OP_RECVMSG
:
6465 return io_recvmsg_prep_async(req
);
6466 case IORING_OP_CONNECT
:
6467 return io_connect_prep_async(req
);
6469 printk_once(KERN_WARNING
"io_uring: prep_async() bad opcode %d\n",
6474 static u32
io_get_sequence(struct io_kiocb
*req
)
6476 u32 seq
= req
->ctx
->cached_sq_head
;
6478 /* need original cached_sq_head, but it was increased for each req */
6479 io_for_each_link(req
, req
)
6484 static bool io_drain_req(struct io_kiocb
*req
)
6486 struct io_kiocb
*pos
;
6487 struct io_ring_ctx
*ctx
= req
->ctx
;
6488 struct io_defer_entry
*de
;
6492 if (req
->flags
& REQ_F_FAIL
) {
6493 io_req_complete_fail_submit(req
);
6498 * If we need to drain a request in the middle of a link, drain the
6499 * head request and the next request/link after the current link.
6500 * Considering sequential execution of links, IOSQE_IO_DRAIN will be
6501 * maintained for every request of our link.
6503 if (ctx
->drain_next
) {
6504 req
->flags
|= REQ_F_IO_DRAIN
;
6505 ctx
->drain_next
= false;
6507 /* not interested in head, start from the first linked */
6508 io_for_each_link(pos
, req
->link
) {
6509 if (pos
->flags
& REQ_F_IO_DRAIN
) {
6510 ctx
->drain_next
= true;
6511 req
->flags
|= REQ_F_IO_DRAIN
;
6516 /* Still need defer if there is pending req in defer list. */
6517 if (likely(list_empty_careful(&ctx
->defer_list
) &&
6518 !(req
->flags
& REQ_F_IO_DRAIN
))) {
6519 ctx
->drain_active
= false;
6523 seq
= io_get_sequence(req
);
6524 /* Still a chance to pass the sequence check */
6525 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
6528 ret
= io_req_prep_async(req
);
6531 io_prep_async_link(req
);
6532 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
6536 io_req_complete_failed(req
, ret
);
6540 spin_lock(&ctx
->completion_lock
);
6541 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
6542 spin_unlock(&ctx
->completion_lock
);
6544 io_queue_async_work(req
, NULL
);
6548 trace_io_uring_defer(ctx
, req
, req
->user_data
);
6551 list_add_tail(&de
->list
, &ctx
->defer_list
);
6552 spin_unlock(&ctx
->completion_lock
);
6556 static void io_clean_op(struct io_kiocb
*req
)
6558 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
6559 switch (req
->opcode
) {
6560 case IORING_OP_READV
:
6561 case IORING_OP_READ_FIXED
:
6562 case IORING_OP_READ
:
6563 kfree((void *)(unsigned long)req
->rw
.addr
);
6565 case IORING_OP_RECVMSG
:
6566 case IORING_OP_RECV
:
6567 kfree(req
->sr_msg
.kbuf
);
6572 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
6573 switch (req
->opcode
) {
6574 case IORING_OP_READV
:
6575 case IORING_OP_READ_FIXED
:
6576 case IORING_OP_READ
:
6577 case IORING_OP_WRITEV
:
6578 case IORING_OP_WRITE_FIXED
:
6579 case IORING_OP_WRITE
: {
6580 struct io_async_rw
*io
= req
->async_data
;
6582 kfree(io
->free_iovec
);
6585 case IORING_OP_RECVMSG
:
6586 case IORING_OP_SENDMSG
: {
6587 struct io_async_msghdr
*io
= req
->async_data
;
6589 kfree(io
->free_iov
);
6592 case IORING_OP_SPLICE
:
6594 if (!(req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
))
6595 io_put_file(req
->splice
.file_in
);
6597 case IORING_OP_OPENAT
:
6598 case IORING_OP_OPENAT2
:
6599 if (req
->open
.filename
)
6600 putname(req
->open
.filename
);
6602 case IORING_OP_RENAMEAT
:
6603 putname(req
->rename
.oldpath
);
6604 putname(req
->rename
.newpath
);
6606 case IORING_OP_UNLINKAT
:
6607 putname(req
->unlink
.filename
);
6609 case IORING_OP_MKDIRAT
:
6610 putname(req
->mkdir
.filename
);
6612 case IORING_OP_SYMLINKAT
:
6613 putname(req
->symlink
.oldpath
);
6614 putname(req
->symlink
.newpath
);
6616 case IORING_OP_LINKAT
:
6617 putname(req
->hardlink
.oldpath
);
6618 putname(req
->hardlink
.newpath
);
6622 if ((req
->flags
& REQ_F_POLLED
) && req
->apoll
) {
6623 kfree(req
->apoll
->double_poll
);
6627 if (req
->flags
& REQ_F_INFLIGHT
) {
6628 struct io_uring_task
*tctx
= req
->task
->io_uring
;
6630 atomic_dec(&tctx
->inflight_tracked
);
6632 if (req
->flags
& REQ_F_CREDS
)
6633 put_cred(req
->creds
);
6635 req
->flags
&= ~IO_REQ_CLEAN_FLAGS
;
6638 static int io_issue_sqe(struct io_kiocb
*req
, unsigned int issue_flags
)
6640 struct io_ring_ctx
*ctx
= req
->ctx
;
6641 const struct cred
*creds
= NULL
;
6644 if ((req
->flags
& REQ_F_CREDS
) && req
->creds
!= current_cred())
6645 creds
= override_creds(req
->creds
);
6647 switch (req
->opcode
) {
6649 ret
= io_nop(req
, issue_flags
);
6651 case IORING_OP_READV
:
6652 case IORING_OP_READ_FIXED
:
6653 case IORING_OP_READ
:
6654 ret
= io_read(req
, issue_flags
);
6656 case IORING_OP_WRITEV
:
6657 case IORING_OP_WRITE_FIXED
:
6658 case IORING_OP_WRITE
:
6659 ret
= io_write(req
, issue_flags
);
6661 case IORING_OP_FSYNC
:
6662 ret
= io_fsync(req
, issue_flags
);
6664 case IORING_OP_POLL_ADD
:
6665 ret
= io_poll_add(req
, issue_flags
);
6667 case IORING_OP_POLL_REMOVE
:
6668 ret
= io_poll_update(req
, issue_flags
);
6670 case IORING_OP_SYNC_FILE_RANGE
:
6671 ret
= io_sync_file_range(req
, issue_flags
);
6673 case IORING_OP_SENDMSG
:
6674 ret
= io_sendmsg(req
, issue_flags
);
6676 case IORING_OP_SEND
:
6677 ret
= io_send(req
, issue_flags
);
6679 case IORING_OP_RECVMSG
:
6680 ret
= io_recvmsg(req
, issue_flags
);
6682 case IORING_OP_RECV
:
6683 ret
= io_recv(req
, issue_flags
);
6685 case IORING_OP_TIMEOUT
:
6686 ret
= io_timeout(req
, issue_flags
);
6688 case IORING_OP_TIMEOUT_REMOVE
:
6689 ret
= io_timeout_remove(req
, issue_flags
);
6691 case IORING_OP_ACCEPT
:
6692 ret
= io_accept(req
, issue_flags
);
6694 case IORING_OP_CONNECT
:
6695 ret
= io_connect(req
, issue_flags
);
6697 case IORING_OP_ASYNC_CANCEL
:
6698 ret
= io_async_cancel(req
, issue_flags
);
6700 case IORING_OP_FALLOCATE
:
6701 ret
= io_fallocate(req
, issue_flags
);
6703 case IORING_OP_OPENAT
:
6704 ret
= io_openat(req
, issue_flags
);
6706 case IORING_OP_CLOSE
:
6707 ret
= io_close(req
, issue_flags
);
6709 case IORING_OP_FILES_UPDATE
:
6710 ret
= io_files_update(req
, issue_flags
);
6712 case IORING_OP_STATX
:
6713 ret
= io_statx(req
, issue_flags
);
6715 case IORING_OP_FADVISE
:
6716 ret
= io_fadvise(req
, issue_flags
);
6718 case IORING_OP_MADVISE
:
6719 ret
= io_madvise(req
, issue_flags
);
6721 case IORING_OP_OPENAT2
:
6722 ret
= io_openat2(req
, issue_flags
);
6724 case IORING_OP_EPOLL_CTL
:
6725 ret
= io_epoll_ctl(req
, issue_flags
);
6727 case IORING_OP_SPLICE
:
6728 ret
= io_splice(req
, issue_flags
);
6730 case IORING_OP_PROVIDE_BUFFERS
:
6731 ret
= io_provide_buffers(req
, issue_flags
);
6733 case IORING_OP_REMOVE_BUFFERS
:
6734 ret
= io_remove_buffers(req
, issue_flags
);
6737 ret
= io_tee(req
, issue_flags
);
6739 case IORING_OP_SHUTDOWN
:
6740 ret
= io_shutdown(req
, issue_flags
);
6742 case IORING_OP_RENAMEAT
:
6743 ret
= io_renameat(req
, issue_flags
);
6745 case IORING_OP_UNLINKAT
:
6746 ret
= io_unlinkat(req
, issue_flags
);
6748 case IORING_OP_MKDIRAT
:
6749 ret
= io_mkdirat(req
, issue_flags
);
6751 case IORING_OP_SYMLINKAT
:
6752 ret
= io_symlinkat(req
, issue_flags
);
6754 case IORING_OP_LINKAT
:
6755 ret
= io_linkat(req
, issue_flags
);
6763 revert_creds(creds
);
6766 /* If the op doesn't have a file, we're not polling for it */
6767 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
)
6768 io_iopoll_req_issued(req
);
6773 static struct io_wq_work
*io_wq_free_work(struct io_wq_work
*work
)
6775 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6777 req
= io_put_req_find_next(req
);
6778 return req
? &req
->work
: NULL
;
6781 static void io_wq_submit_work(struct io_wq_work
*work
)
6783 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6784 struct io_kiocb
*timeout
;
6787 /* one will be dropped by ->io_free_work() after returning to io-wq */
6788 if (!(req
->flags
& REQ_F_REFCOUNT
))
6789 __io_req_set_refcount(req
, 2);
6793 timeout
= io_prep_linked_timeout(req
);
6795 io_queue_linked_timeout(timeout
);
6797 /* either cancelled or io-wq is dying, so don't touch tctx->iowq */
6798 if (work
->flags
& IO_WQ_WORK_CANCEL
)
6803 ret
= io_issue_sqe(req
, 0);
6805 * We can get EAGAIN for polled IO even though we're
6806 * forcing a sync submission from here, since we can't
6807 * wait for request slots on the block side.
6815 /* avoid locking problems by failing it from a clean context */
6817 io_req_task_queue_fail(req
, ret
);
6820 static inline struct io_fixed_file
*io_fixed_file_slot(struct io_file_table
*table
,
6823 return &table
->files
[i
];
6826 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6829 struct io_fixed_file
*slot
= io_fixed_file_slot(&ctx
->file_table
, index
);
6831 return (struct file
*) (slot
->file_ptr
& FFS_MASK
);
6834 static void io_fixed_file_set(struct io_fixed_file
*file_slot
, struct file
*file
)
6836 unsigned long file_ptr
= (unsigned long) file
;
6838 if (__io_file_supports_nowait(file
, READ
))
6839 file_ptr
|= FFS_ASYNC_READ
;
6840 if (__io_file_supports_nowait(file
, WRITE
))
6841 file_ptr
|= FFS_ASYNC_WRITE
;
6842 if (S_ISREG(file_inode(file
)->i_mode
))
6843 file_ptr
|= FFS_ISREG
;
6844 file_slot
->file_ptr
= file_ptr
;
6847 static inline struct file
*io_file_get_fixed(struct io_ring_ctx
*ctx
,
6848 struct io_kiocb
*req
, int fd
)
6851 unsigned long file_ptr
;
6853 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6855 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6856 file_ptr
= io_fixed_file_slot(&ctx
->file_table
, fd
)->file_ptr
;
6857 file
= (struct file
*) (file_ptr
& FFS_MASK
);
6858 file_ptr
&= ~FFS_MASK
;
6859 /* mask in overlapping REQ_F and FFS bits */
6860 req
->flags
|= (file_ptr
<< REQ_F_NOWAIT_READ_BIT
);
6861 io_req_set_rsrc_node(req
);
6865 static struct file
*io_file_get_normal(struct io_ring_ctx
*ctx
,
6866 struct io_kiocb
*req
, int fd
)
6868 struct file
*file
= fget(fd
);
6870 trace_io_uring_file_get(ctx
, fd
);
6872 /* we don't allow fixed io_uring files */
6873 if (file
&& unlikely(file
->f_op
== &io_uring_fops
))
6874 io_req_track_inflight(req
);
6878 static inline struct file
*io_file_get(struct io_ring_ctx
*ctx
,
6879 struct io_kiocb
*req
, int fd
, bool fixed
)
6882 return io_file_get_fixed(ctx
, req
, fd
);
6884 return io_file_get_normal(ctx
, req
, fd
);
6887 static void io_req_task_link_timeout(struct io_kiocb
*req
, bool *locked
)
6889 struct io_kiocb
*prev
= req
->timeout
.prev
;
6893 ret
= io_try_cancel_userdata(req
, prev
->user_data
);
6894 io_req_complete_post(req
, ret
?: -ETIME
, 0);
6897 io_req_complete_post(req
, -ETIME
, 0);
6901 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6903 struct io_timeout_data
*data
= container_of(timer
,
6904 struct io_timeout_data
, timer
);
6905 struct io_kiocb
*prev
, *req
= data
->req
;
6906 struct io_ring_ctx
*ctx
= req
->ctx
;
6907 unsigned long flags
;
6909 spin_lock_irqsave(&ctx
->timeout_lock
, flags
);
6910 prev
= req
->timeout
.head
;
6911 req
->timeout
.head
= NULL
;
6914 * We don't expect the list to be empty, that will only happen if we
6915 * race with the completion of the linked work.
6918 io_remove_next_linked(prev
);
6919 if (!req_ref_inc_not_zero(prev
))
6922 list_del(&req
->timeout
.list
);
6923 req
->timeout
.prev
= prev
;
6924 spin_unlock_irqrestore(&ctx
->timeout_lock
, flags
);
6926 req
->io_task_work
.func
= io_req_task_link_timeout
;
6927 io_req_task_work_add(req
);
6928 return HRTIMER_NORESTART
;
6931 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6933 struct io_ring_ctx
*ctx
= req
->ctx
;
6935 spin_lock_irq(&ctx
->timeout_lock
);
6937 * If the back reference is NULL, then our linked request finished
6938 * before we got a chance to setup the timer
6940 if (req
->timeout
.head
) {
6941 struct io_timeout_data
*data
= req
->async_data
;
6943 data
->timer
.function
= io_link_timeout_fn
;
6944 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6946 list_add_tail(&req
->timeout
.list
, &ctx
->ltimeout_list
);
6948 spin_unlock_irq(&ctx
->timeout_lock
);
6949 /* drop submission reference */
6953 static void __io_queue_sqe(struct io_kiocb
*req
)
6954 __must_hold(&req
->ctx
->uring_lock
)
6956 struct io_kiocb
*linked_timeout
;
6960 ret
= io_issue_sqe(req
, IO_URING_F_NONBLOCK
|IO_URING_F_COMPLETE_DEFER
);
6963 * We async punt it if the file wasn't marked NOWAIT, or if the file
6964 * doesn't support non-blocking read/write attempts
6967 if (req
->flags
& REQ_F_COMPLETE_INLINE
) {
6968 struct io_ring_ctx
*ctx
= req
->ctx
;
6969 struct io_submit_state
*state
= &ctx
->submit_state
;
6971 state
->compl_reqs
[state
->compl_nr
++] = req
;
6972 if (state
->compl_nr
== ARRAY_SIZE(state
->compl_reqs
))
6973 io_submit_flush_completions(ctx
);
6977 linked_timeout
= io_prep_linked_timeout(req
);
6979 io_queue_linked_timeout(linked_timeout
);
6980 } else if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6981 linked_timeout
= io_prep_linked_timeout(req
);
6983 switch (io_arm_poll_handler(req
)) {
6984 case IO_APOLL_READY
:
6986 io_unprep_linked_timeout(req
);
6988 case IO_APOLL_ABORTED
:
6990 * Queued up for async execution, worker will release
6991 * submit reference when the iocb is actually submitted.
6993 io_queue_async_work(req
, NULL
);
6998 io_queue_linked_timeout(linked_timeout
);
7000 io_req_complete_failed(req
, ret
);
7004 static inline void io_queue_sqe(struct io_kiocb
*req
)
7005 __must_hold(&req
->ctx
->uring_lock
)
7007 if (unlikely(req
->ctx
->drain_active
) && io_drain_req(req
))
7010 if (likely(!(req
->flags
& (REQ_F_FORCE_ASYNC
| REQ_F_FAIL
)))) {
7011 __io_queue_sqe(req
);
7012 } else if (req
->flags
& REQ_F_FAIL
) {
7013 io_req_complete_fail_submit(req
);
7015 int ret
= io_req_prep_async(req
);
7018 io_req_complete_failed(req
, ret
);
7020 io_queue_async_work(req
, NULL
);
7025 * Check SQE restrictions (opcode and flags).
7027 * Returns 'true' if SQE is allowed, 'false' otherwise.
7029 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
7030 struct io_kiocb
*req
,
7031 unsigned int sqe_flags
)
7033 if (likely(!ctx
->restricted
))
7036 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
7039 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
7040 ctx
->restrictions
.sqe_flags_required
)
7043 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
7044 ctx
->restrictions
.sqe_flags_required
))
7050 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
7051 const struct io_uring_sqe
*sqe
)
7052 __must_hold(&ctx
->uring_lock
)
7054 struct io_submit_state
*state
;
7055 unsigned int sqe_flags
;
7056 int personality
, ret
= 0;
7058 /* req is partially pre-initialised, see io_preinit_req() */
7059 req
->opcode
= READ_ONCE(sqe
->opcode
);
7060 /* same numerical values with corresponding REQ_F_*, safe to copy */
7061 req
->flags
= sqe_flags
= READ_ONCE(sqe
->flags
);
7062 req
->user_data
= READ_ONCE(sqe
->user_data
);
7064 req
->fixed_rsrc_refs
= NULL
;
7065 req
->task
= current
;
7067 /* enforce forwards compatibility on users */
7068 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
7070 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
7072 if (!io_check_restriction(ctx
, req
, sqe_flags
))
7075 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
7076 !io_op_defs
[req
->opcode
].buffer_select
)
7078 if (unlikely(sqe_flags
& IOSQE_IO_DRAIN
))
7079 ctx
->drain_active
= true;
7081 personality
= READ_ONCE(sqe
->personality
);
7083 req
->creds
= xa_load(&ctx
->personalities
, personality
);
7086 get_cred(req
->creds
);
7087 req
->flags
|= REQ_F_CREDS
;
7089 state
= &ctx
->submit_state
;
7092 * Plug now if we have more than 1 IO left after this, and the target
7093 * is potentially a read/write to block based storage.
7095 if (!state
->plug_started
&& state
->ios_left
> 1 &&
7096 io_op_defs
[req
->opcode
].plug
) {
7097 blk_start_plug(&state
->plug
);
7098 state
->plug_started
= true;
7101 if (io_op_defs
[req
->opcode
].needs_file
) {
7102 req
->file
= io_file_get(ctx
, req
, READ_ONCE(sqe
->fd
),
7103 (sqe_flags
& IOSQE_FIXED_FILE
));
7104 if (unlikely(!req
->file
))
7112 static int io_submit_sqe(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
7113 const struct io_uring_sqe
*sqe
)
7114 __must_hold(&ctx
->uring_lock
)
7116 struct io_submit_link
*link
= &ctx
->submit_state
.link
;
7119 ret
= io_init_req(ctx
, req
, sqe
);
7120 if (unlikely(ret
)) {
7122 /* fail even hard links since we don't submit */
7125 * we can judge a link req is failed or cancelled by if
7126 * REQ_F_FAIL is set, but the head is an exception since
7127 * it may be set REQ_F_FAIL because of other req's failure
7128 * so let's leverage req->result to distinguish if a head
7129 * is set REQ_F_FAIL because of its failure or other req's
7130 * failure so that we can set the correct ret code for it.
7131 * init result here to avoid affecting the normal path.
7133 if (!(link
->head
->flags
& REQ_F_FAIL
))
7134 req_fail_link_node(link
->head
, -ECANCELED
);
7135 } else if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
7137 * the current req is a normal req, we should return
7138 * error and thus break the submittion loop.
7140 io_req_complete_failed(req
, ret
);
7143 req_fail_link_node(req
, ret
);
7145 ret
= io_req_prep(req
, sqe
);
7150 /* don't need @sqe from now on */
7151 trace_io_uring_submit_sqe(ctx
, req
, req
->opcode
, req
->user_data
,
7153 ctx
->flags
& IORING_SETUP_SQPOLL
);
7156 * If we already have a head request, queue this one for async
7157 * submittal once the head completes. If we don't have a head but
7158 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
7159 * submitted sync once the chain is complete. If none of those
7160 * conditions are true (normal request), then just queue it.
7163 struct io_kiocb
*head
= link
->head
;
7165 if (!(req
->flags
& REQ_F_FAIL
)) {
7166 ret
= io_req_prep_async(req
);
7167 if (unlikely(ret
)) {
7168 req_fail_link_node(req
, ret
);
7169 if (!(head
->flags
& REQ_F_FAIL
))
7170 req_fail_link_node(head
, -ECANCELED
);
7173 trace_io_uring_link(ctx
, req
, head
);
7174 link
->last
->link
= req
;
7177 /* last request of a link, enqueue the link */
7178 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
7183 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
7195 * Batched submission is done, ensure local IO is flushed out.
7197 static void io_submit_state_end(struct io_submit_state
*state
,
7198 struct io_ring_ctx
*ctx
)
7200 if (state
->link
.head
)
7201 io_queue_sqe(state
->link
.head
);
7202 if (state
->compl_nr
)
7203 io_submit_flush_completions(ctx
);
7204 if (state
->plug_started
)
7205 blk_finish_plug(&state
->plug
);
7209 * Start submission side cache.
7211 static void io_submit_state_start(struct io_submit_state
*state
,
7212 unsigned int max_ios
)
7214 state
->plug_started
= false;
7215 state
->ios_left
= max_ios
;
7216 /* set only head, no need to init link_last in advance */
7217 state
->link
.head
= NULL
;
7220 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
7222 struct io_rings
*rings
= ctx
->rings
;
7225 * Ensure any loads from the SQEs are done at this point,
7226 * since once we write the new head, the application could
7227 * write new data to them.
7229 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
7233 * Fetch an sqe, if one is available. Note this returns a pointer to memory
7234 * that is mapped by userspace. This means that care needs to be taken to
7235 * ensure that reads are stable, as we cannot rely on userspace always
7236 * being a good citizen. If members of the sqe are validated and then later
7237 * used, it's important that those reads are done through READ_ONCE() to
7238 * prevent a re-load down the line.
7240 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
7242 unsigned head
, mask
= ctx
->sq_entries
- 1;
7243 unsigned sq_idx
= ctx
->cached_sq_head
++ & mask
;
7246 * The cached sq head (or cq tail) serves two purposes:
7248 * 1) allows us to batch the cost of updating the user visible
7250 * 2) allows the kernel side to track the head on its own, even
7251 * though the application is the one updating it.
7253 head
= READ_ONCE(ctx
->sq_array
[sq_idx
]);
7254 if (likely(head
< ctx
->sq_entries
))
7255 return &ctx
->sq_sqes
[head
];
7257 /* drop invalid entries */
7259 WRITE_ONCE(ctx
->rings
->sq_dropped
,
7260 READ_ONCE(ctx
->rings
->sq_dropped
) + 1);
7264 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
7265 __must_hold(&ctx
->uring_lock
)
7269 /* make sure SQ entry isn't read before tail */
7270 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
7271 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
7273 io_get_task_refs(nr
);
7275 io_submit_state_start(&ctx
->submit_state
, nr
);
7276 while (submitted
< nr
) {
7277 const struct io_uring_sqe
*sqe
;
7278 struct io_kiocb
*req
;
7280 req
= io_alloc_req(ctx
);
7281 if (unlikely(!req
)) {
7283 submitted
= -EAGAIN
;
7286 sqe
= io_get_sqe(ctx
);
7287 if (unlikely(!sqe
)) {
7288 list_add(&req
->inflight_entry
, &ctx
->submit_state
.free_list
);
7291 /* will complete beyond this point, count as submitted */
7293 if (io_submit_sqe(ctx
, req
, sqe
))
7297 if (unlikely(submitted
!= nr
)) {
7298 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
7299 int unused
= nr
- ref_used
;
7301 current
->io_uring
->cached_refs
+= unused
;
7302 percpu_ref_put_many(&ctx
->refs
, unused
);
7305 io_submit_state_end(&ctx
->submit_state
, ctx
);
7306 /* Commit SQ ring head once we've consumed and submitted all SQEs */
7307 io_commit_sqring(ctx
);
7312 static inline bool io_sqd_events_pending(struct io_sq_data
*sqd
)
7314 return READ_ONCE(sqd
->state
);
7317 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
7319 /* Tell userspace we may need a wakeup call */
7320 spin_lock(&ctx
->completion_lock
);
7321 WRITE_ONCE(ctx
->rings
->sq_flags
,
7322 ctx
->rings
->sq_flags
| IORING_SQ_NEED_WAKEUP
);
7323 spin_unlock(&ctx
->completion_lock
);
7326 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
7328 spin_lock(&ctx
->completion_lock
);
7329 WRITE_ONCE(ctx
->rings
->sq_flags
,
7330 ctx
->rings
->sq_flags
& ~IORING_SQ_NEED_WAKEUP
);
7331 spin_unlock(&ctx
->completion_lock
);
7334 static int __io_sq_thread(struct io_ring_ctx
*ctx
, bool cap_entries
)
7336 unsigned int to_submit
;
7339 to_submit
= io_sqring_entries(ctx
);
7340 /* if we're handling multiple rings, cap submit size for fairness */
7341 if (cap_entries
&& to_submit
> IORING_SQPOLL_CAP_ENTRIES_VALUE
)
7342 to_submit
= IORING_SQPOLL_CAP_ENTRIES_VALUE
;
7344 if (!list_empty(&ctx
->iopoll_list
) || to_submit
) {
7345 unsigned nr_events
= 0;
7346 const struct cred
*creds
= NULL
;
7348 if (ctx
->sq_creds
!= current_cred())
7349 creds
= override_creds(ctx
->sq_creds
);
7351 mutex_lock(&ctx
->uring_lock
);
7352 if (!list_empty(&ctx
->iopoll_list
))
7353 io_do_iopoll(ctx
, &nr_events
, 0);
7356 * Don't submit if refs are dying, good for io_uring_register(),
7357 * but also it is relied upon by io_ring_exit_work()
7359 if (to_submit
&& likely(!percpu_ref_is_dying(&ctx
->refs
)) &&
7360 !(ctx
->flags
& IORING_SETUP_R_DISABLED
))
7361 ret
= io_submit_sqes(ctx
, to_submit
);
7362 mutex_unlock(&ctx
->uring_lock
);
7364 if (to_submit
&& wq_has_sleeper(&ctx
->sqo_sq_wait
))
7365 wake_up(&ctx
->sqo_sq_wait
);
7367 revert_creds(creds
);
7373 static void io_sqd_update_thread_idle(struct io_sq_data
*sqd
)
7375 struct io_ring_ctx
*ctx
;
7376 unsigned sq_thread_idle
= 0;
7378 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7379 sq_thread_idle
= max(sq_thread_idle
, ctx
->sq_thread_idle
);
7380 sqd
->sq_thread_idle
= sq_thread_idle
;
7383 static bool io_sqd_handle_event(struct io_sq_data
*sqd
)
7385 bool did_sig
= false;
7386 struct ksignal ksig
;
7388 if (test_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
) ||
7389 signal_pending(current
)) {
7390 mutex_unlock(&sqd
->lock
);
7391 if (signal_pending(current
))
7392 did_sig
= get_signal(&ksig
);
7394 mutex_lock(&sqd
->lock
);
7396 return did_sig
|| test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
);
7399 static int io_sq_thread(void *data
)
7401 struct io_sq_data
*sqd
= data
;
7402 struct io_ring_ctx
*ctx
;
7403 unsigned long timeout
= 0;
7404 char buf
[TASK_COMM_LEN
];
7407 snprintf(buf
, sizeof(buf
), "iou-sqp-%d", sqd
->task_pid
);
7408 set_task_comm(current
, buf
);
7410 if (sqd
->sq_cpu
!= -1)
7411 set_cpus_allowed_ptr(current
, cpumask_of(sqd
->sq_cpu
));
7413 set_cpus_allowed_ptr(current
, cpu_online_mask
);
7414 current
->flags
|= PF_NO_SETAFFINITY
;
7416 mutex_lock(&sqd
->lock
);
7418 bool cap_entries
, sqt_spin
= false;
7420 if (io_sqd_events_pending(sqd
) || signal_pending(current
)) {
7421 if (io_sqd_handle_event(sqd
))
7423 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7426 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
7427 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7428 int ret
= __io_sq_thread(ctx
, cap_entries
);
7430 if (!sqt_spin
&& (ret
> 0 || !list_empty(&ctx
->iopoll_list
)))
7433 if (io_run_task_work())
7436 if (sqt_spin
|| !time_after(jiffies
, timeout
)) {
7439 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7443 prepare_to_wait(&sqd
->wait
, &wait
, TASK_INTERRUPTIBLE
);
7444 if (!io_sqd_events_pending(sqd
) && !current
->task_works
) {
7445 bool needs_sched
= true;
7447 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
7448 io_ring_set_wakeup_flag(ctx
);
7450 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
7451 !list_empty_careful(&ctx
->iopoll_list
)) {
7452 needs_sched
= false;
7455 if (io_sqring_entries(ctx
)) {
7456 needs_sched
= false;
7462 mutex_unlock(&sqd
->lock
);
7464 mutex_lock(&sqd
->lock
);
7466 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7467 io_ring_clear_wakeup_flag(ctx
);
7470 finish_wait(&sqd
->wait
, &wait
);
7471 timeout
= jiffies
+ sqd
->sq_thread_idle
;
7474 io_uring_cancel_generic(true, sqd
);
7476 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
7477 io_ring_set_wakeup_flag(ctx
);
7479 mutex_unlock(&sqd
->lock
);
7481 complete(&sqd
->exited
);
7485 struct io_wait_queue
{
7486 struct wait_queue_entry wq
;
7487 struct io_ring_ctx
*ctx
;
7489 unsigned nr_timeouts
;
7492 static inline bool io_should_wake(struct io_wait_queue
*iowq
)
7494 struct io_ring_ctx
*ctx
= iowq
->ctx
;
7495 int dist
= ctx
->cached_cq_tail
- (int) iowq
->cq_tail
;
7498 * Wake up if we have enough events, or if a timeout occurred since we
7499 * started waiting. For timeouts, we always want to return to userspace,
7500 * regardless of event count.
7502 return dist
>= 0 || atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
7505 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
7506 int wake_flags
, void *key
)
7508 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
7512 * Cannot safely flush overflowed CQEs from here, ensure we wake up
7513 * the task, and the next invocation will do it.
7515 if (io_should_wake(iowq
) || test_bit(0, &iowq
->ctx
->check_cq_overflow
))
7516 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
7520 static int io_run_task_work_sig(void)
7522 if (io_run_task_work())
7524 if (!signal_pending(current
))
7526 if (test_thread_flag(TIF_NOTIFY_SIGNAL
))
7527 return -ERESTARTSYS
;
7531 /* when returns >0, the caller should retry */
7532 static inline int io_cqring_wait_schedule(struct io_ring_ctx
*ctx
,
7533 struct io_wait_queue
*iowq
,
7534 signed long *timeout
)
7538 /* make sure we run task_work before checking for signals */
7539 ret
= io_run_task_work_sig();
7540 if (ret
|| io_should_wake(iowq
))
7542 /* let the caller flush overflows, retry */
7543 if (test_bit(0, &ctx
->check_cq_overflow
))
7546 *timeout
= schedule_timeout(*timeout
);
7547 return !*timeout
? -ETIME
: 1;
7551 * Wait until events become available, if we don't already have some. The
7552 * application must reap them itself, as they reside on the shared cq ring.
7554 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
7555 const sigset_t __user
*sig
, size_t sigsz
,
7556 struct __kernel_timespec __user
*uts
)
7558 struct io_wait_queue iowq
;
7559 struct io_rings
*rings
= ctx
->rings
;
7560 signed long timeout
= MAX_SCHEDULE_TIMEOUT
;
7564 io_cqring_overflow_flush(ctx
);
7565 if (io_cqring_events(ctx
) >= min_events
)
7567 if (!io_run_task_work())
7572 struct timespec64 ts
;
7574 if (get_timespec64(&ts
, uts
))
7576 timeout
= timespec64_to_jiffies(&ts
);
7580 #ifdef CONFIG_COMPAT
7581 if (in_compat_syscall())
7582 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
7586 ret
= set_user_sigmask(sig
, sigsz
);
7592 init_waitqueue_func_entry(&iowq
.wq
, io_wake_function
);
7593 iowq
.wq
.private = current
;
7594 INIT_LIST_HEAD(&iowq
.wq
.entry
);
7596 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
7597 iowq
.cq_tail
= READ_ONCE(ctx
->rings
->cq
.head
) + min_events
;
7599 trace_io_uring_cqring_wait(ctx
, min_events
);
7601 /* if we can't even flush overflow, don't wait for more */
7602 if (!io_cqring_overflow_flush(ctx
)) {
7606 prepare_to_wait_exclusive(&ctx
->cq_wait
, &iowq
.wq
,
7607 TASK_INTERRUPTIBLE
);
7608 ret
= io_cqring_wait_schedule(ctx
, &iowq
, &timeout
);
7609 finish_wait(&ctx
->cq_wait
, &iowq
.wq
);
7613 restore_saved_sigmask_unless(ret
== -EINTR
);
7615 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
7618 static void io_free_page_table(void **table
, size_t size
)
7620 unsigned i
, nr_tables
= DIV_ROUND_UP(size
, PAGE_SIZE
);
7622 for (i
= 0; i
< nr_tables
; i
++)
7627 static void **io_alloc_page_table(size_t size
)
7629 unsigned i
, nr_tables
= DIV_ROUND_UP(size
, PAGE_SIZE
);
7630 size_t init_size
= size
;
7633 table
= kcalloc(nr_tables
, sizeof(*table
), GFP_KERNEL_ACCOUNT
);
7637 for (i
= 0; i
< nr_tables
; i
++) {
7638 unsigned int this_size
= min_t(size_t, size
, PAGE_SIZE
);
7640 table
[i
] = kzalloc(this_size
, GFP_KERNEL_ACCOUNT
);
7642 io_free_page_table(table
, init_size
);
7650 static void io_rsrc_node_destroy(struct io_rsrc_node
*ref_node
)
7652 percpu_ref_exit(&ref_node
->refs
);
7656 static void io_rsrc_node_ref_zero(struct percpu_ref
*ref
)
7658 struct io_rsrc_node
*node
= container_of(ref
, struct io_rsrc_node
, refs
);
7659 struct io_ring_ctx
*ctx
= node
->rsrc_data
->ctx
;
7660 unsigned long flags
;
7661 bool first_add
= false;
7663 spin_lock_irqsave(&ctx
->rsrc_ref_lock
, flags
);
7666 while (!list_empty(&ctx
->rsrc_ref_list
)) {
7667 node
= list_first_entry(&ctx
->rsrc_ref_list
,
7668 struct io_rsrc_node
, node
);
7669 /* recycle ref nodes in order */
7672 list_del(&node
->node
);
7673 first_add
|= llist_add(&node
->llist
, &ctx
->rsrc_put_llist
);
7675 spin_unlock_irqrestore(&ctx
->rsrc_ref_lock
, flags
);
7678 mod_delayed_work(system_wq
, &ctx
->rsrc_put_work
, HZ
);
7681 static struct io_rsrc_node
*io_rsrc_node_alloc(struct io_ring_ctx
*ctx
)
7683 struct io_rsrc_node
*ref_node
;
7685 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7689 if (percpu_ref_init(&ref_node
->refs
, io_rsrc_node_ref_zero
,
7694 INIT_LIST_HEAD(&ref_node
->node
);
7695 INIT_LIST_HEAD(&ref_node
->rsrc_list
);
7696 ref_node
->done
= false;
7700 static void io_rsrc_node_switch(struct io_ring_ctx
*ctx
,
7701 struct io_rsrc_data
*data_to_kill
)
7703 WARN_ON_ONCE(!ctx
->rsrc_backup_node
);
7704 WARN_ON_ONCE(data_to_kill
&& !ctx
->rsrc_node
);
7707 struct io_rsrc_node
*rsrc_node
= ctx
->rsrc_node
;
7709 rsrc_node
->rsrc_data
= data_to_kill
;
7710 spin_lock_irq(&ctx
->rsrc_ref_lock
);
7711 list_add_tail(&rsrc_node
->node
, &ctx
->rsrc_ref_list
);
7712 spin_unlock_irq(&ctx
->rsrc_ref_lock
);
7714 atomic_inc(&data_to_kill
->refs
);
7715 percpu_ref_kill(&rsrc_node
->refs
);
7716 ctx
->rsrc_node
= NULL
;
7719 if (!ctx
->rsrc_node
) {
7720 ctx
->rsrc_node
= ctx
->rsrc_backup_node
;
7721 ctx
->rsrc_backup_node
= NULL
;
7725 static int io_rsrc_node_switch_start(struct io_ring_ctx
*ctx
)
7727 if (ctx
->rsrc_backup_node
)
7729 ctx
->rsrc_backup_node
= io_rsrc_node_alloc(ctx
);
7730 return ctx
->rsrc_backup_node
? 0 : -ENOMEM
;
7733 static int io_rsrc_ref_quiesce(struct io_rsrc_data
*data
, struct io_ring_ctx
*ctx
)
7737 /* As we may drop ->uring_lock, other task may have started quiesce */
7741 data
->quiesce
= true;
7743 ret
= io_rsrc_node_switch_start(ctx
);
7746 io_rsrc_node_switch(ctx
, data
);
7748 /* kill initial ref, already quiesced if zero */
7749 if (atomic_dec_and_test(&data
->refs
))
7751 mutex_unlock(&ctx
->uring_lock
);
7752 flush_delayed_work(&ctx
->rsrc_put_work
);
7753 ret
= wait_for_completion_interruptible(&data
->done
);
7755 mutex_lock(&ctx
->uring_lock
);
7759 atomic_inc(&data
->refs
);
7760 /* wait for all works potentially completing data->done */
7761 flush_delayed_work(&ctx
->rsrc_put_work
);
7762 reinit_completion(&data
->done
);
7764 ret
= io_run_task_work_sig();
7765 mutex_lock(&ctx
->uring_lock
);
7767 data
->quiesce
= false;
7772 static u64
*io_get_tag_slot(struct io_rsrc_data
*data
, unsigned int idx
)
7774 unsigned int off
= idx
& IO_RSRC_TAG_TABLE_MASK
;
7775 unsigned int table_idx
= idx
>> IO_RSRC_TAG_TABLE_SHIFT
;
7777 return &data
->tags
[table_idx
][off
];
7780 static void io_rsrc_data_free(struct io_rsrc_data
*data
)
7782 size_t size
= data
->nr
* sizeof(data
->tags
[0][0]);
7785 io_free_page_table((void **)data
->tags
, size
);
7789 static int io_rsrc_data_alloc(struct io_ring_ctx
*ctx
, rsrc_put_fn
*do_put
,
7790 u64 __user
*utags
, unsigned nr
,
7791 struct io_rsrc_data
**pdata
)
7793 struct io_rsrc_data
*data
;
7797 data
= kzalloc(sizeof(*data
), GFP_KERNEL
);
7800 data
->tags
= (u64
**)io_alloc_page_table(nr
* sizeof(data
->tags
[0][0]));
7808 data
->do_put
= do_put
;
7811 for (i
= 0; i
< nr
; i
++) {
7812 u64
*tag_slot
= io_get_tag_slot(data
, i
);
7814 if (copy_from_user(tag_slot
, &utags
[i
],
7820 atomic_set(&data
->refs
, 1);
7821 init_completion(&data
->done
);
7825 io_rsrc_data_free(data
);
7829 static bool io_alloc_file_tables(struct io_file_table
*table
, unsigned nr_files
)
7831 table
->files
= kvcalloc(nr_files
, sizeof(table
->files
[0]),
7832 GFP_KERNEL_ACCOUNT
);
7833 return !!table
->files
;
7836 static void io_free_file_tables(struct io_file_table
*table
)
7838 kvfree(table
->files
);
7839 table
->files
= NULL
;
7842 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7844 #if defined(CONFIG_UNIX)
7845 if (ctx
->ring_sock
) {
7846 struct sock
*sock
= ctx
->ring_sock
->sk
;
7847 struct sk_buff
*skb
;
7849 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
7855 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7858 file
= io_file_from_index(ctx
, i
);
7863 io_free_file_tables(&ctx
->file_table
);
7864 io_rsrc_data_free(ctx
->file_data
);
7865 ctx
->file_data
= NULL
;
7866 ctx
->nr_user_files
= 0;
7869 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
7873 if (!ctx
->file_data
)
7875 ret
= io_rsrc_ref_quiesce(ctx
->file_data
, ctx
);
7877 __io_sqe_files_unregister(ctx
);
7881 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7882 __releases(&sqd
->lock
)
7884 WARN_ON_ONCE(sqd
->thread
== current
);
7887 * Do the dance but not conditional clear_bit() because it'd race with
7888 * other threads incrementing park_pending and setting the bit.
7890 clear_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7891 if (atomic_dec_return(&sqd
->park_pending
))
7892 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7893 mutex_unlock(&sqd
->lock
);
7896 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7897 __acquires(&sqd
->lock
)
7899 WARN_ON_ONCE(sqd
->thread
== current
);
7901 atomic_inc(&sqd
->park_pending
);
7902 set_bit(IO_SQ_THREAD_SHOULD_PARK
, &sqd
->state
);
7903 mutex_lock(&sqd
->lock
);
7905 wake_up_process(sqd
->thread
);
7908 static void io_sq_thread_stop(struct io_sq_data
*sqd
)
7910 WARN_ON_ONCE(sqd
->thread
== current
);
7911 WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
));
7913 set_bit(IO_SQ_THREAD_SHOULD_STOP
, &sqd
->state
);
7914 mutex_lock(&sqd
->lock
);
7916 wake_up_process(sqd
->thread
);
7917 mutex_unlock(&sqd
->lock
);
7918 wait_for_completion(&sqd
->exited
);
7921 static void io_put_sq_data(struct io_sq_data
*sqd
)
7923 if (refcount_dec_and_test(&sqd
->refs
)) {
7924 WARN_ON_ONCE(atomic_read(&sqd
->park_pending
));
7926 io_sq_thread_stop(sqd
);
7931 static void io_sq_thread_finish(struct io_ring_ctx
*ctx
)
7933 struct io_sq_data
*sqd
= ctx
->sq_data
;
7936 io_sq_thread_park(sqd
);
7937 list_del_init(&ctx
->sqd_list
);
7938 io_sqd_update_thread_idle(sqd
);
7939 io_sq_thread_unpark(sqd
);
7941 io_put_sq_data(sqd
);
7942 ctx
->sq_data
= NULL
;
7946 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7948 struct io_ring_ctx
*ctx_attach
;
7949 struct io_sq_data
*sqd
;
7952 f
= fdget(p
->wq_fd
);
7954 return ERR_PTR(-ENXIO
);
7955 if (f
.file
->f_op
!= &io_uring_fops
) {
7957 return ERR_PTR(-EINVAL
);
7960 ctx_attach
= f
.file
->private_data
;
7961 sqd
= ctx_attach
->sq_data
;
7964 return ERR_PTR(-EINVAL
);
7966 if (sqd
->task_tgid
!= current
->tgid
) {
7968 return ERR_PTR(-EPERM
);
7971 refcount_inc(&sqd
->refs
);
7976 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
,
7979 struct io_sq_data
*sqd
;
7982 if (p
->flags
& IORING_SETUP_ATTACH_WQ
) {
7983 sqd
= io_attach_sq_data(p
);
7988 /* fall through for EPERM case, setup new sqd/task */
7989 if (PTR_ERR(sqd
) != -EPERM
)
7993 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7995 return ERR_PTR(-ENOMEM
);
7997 atomic_set(&sqd
->park_pending
, 0);
7998 refcount_set(&sqd
->refs
, 1);
7999 INIT_LIST_HEAD(&sqd
->ctx_list
);
8000 mutex_init(&sqd
->lock
);
8001 init_waitqueue_head(&sqd
->wait
);
8002 init_completion(&sqd
->exited
);
8006 #if defined(CONFIG_UNIX)
8008 * Ensure the UNIX gc is aware of our file set, so we are certain that
8009 * the io_uring can be safely unregistered on process exit, even if we have
8010 * loops in the file referencing.
8012 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
8014 struct sock
*sk
= ctx
->ring_sock
->sk
;
8015 struct scm_fp_list
*fpl
;
8016 struct sk_buff
*skb
;
8019 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
8023 skb
= alloc_skb(0, GFP_KERNEL
);
8032 fpl
->user
= get_uid(current_user());
8033 for (i
= 0; i
< nr
; i
++) {
8034 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
8038 fpl
->fp
[nr_files
] = get_file(file
);
8039 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
8044 fpl
->max
= SCM_MAX_FD
;
8045 fpl
->count
= nr_files
;
8046 UNIXCB(skb
).fp
= fpl
;
8047 skb
->destructor
= unix_destruct_scm
;
8048 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
8049 skb_queue_head(&sk
->sk_receive_queue
, skb
);
8051 for (i
= 0; i
< nr_files
; i
++)
8062 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
8063 * causes regular reference counting to break down. We rely on the UNIX
8064 * garbage collection to take care of this problem for us.
8066 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
8068 unsigned left
, total
;
8072 left
= ctx
->nr_user_files
;
8074 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
8076 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
8080 total
+= this_files
;
8086 while (total
< ctx
->nr_user_files
) {
8087 struct file
*file
= io_file_from_index(ctx
, total
);
8097 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
8103 static void io_rsrc_file_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
8105 struct file
*file
= prsrc
->file
;
8106 #if defined(CONFIG_UNIX)
8107 struct sock
*sock
= ctx
->ring_sock
->sk
;
8108 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
8109 struct sk_buff
*skb
;
8112 __skb_queue_head_init(&list
);
8115 * Find the skb that holds this file in its SCM_RIGHTS. When found,
8116 * remove this entry and rearrange the file array.
8118 skb
= skb_dequeue(head
);
8120 struct scm_fp_list
*fp
;
8122 fp
= UNIXCB(skb
).fp
;
8123 for (i
= 0; i
< fp
->count
; i
++) {
8126 if (fp
->fp
[i
] != file
)
8129 unix_notinflight(fp
->user
, fp
->fp
[i
]);
8130 left
= fp
->count
- 1 - i
;
8132 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
8133 left
* sizeof(struct file
*));
8140 __skb_queue_tail(&list
, skb
);
8150 __skb_queue_tail(&list
, skb
);
8152 skb
= skb_dequeue(head
);
8155 if (skb_peek(&list
)) {
8156 spin_lock_irq(&head
->lock
);
8157 while ((skb
= __skb_dequeue(&list
)) != NULL
)
8158 __skb_queue_tail(head
, skb
);
8159 spin_unlock_irq(&head
->lock
);
8166 static void __io_rsrc_put_work(struct io_rsrc_node
*ref_node
)
8168 struct io_rsrc_data
*rsrc_data
= ref_node
->rsrc_data
;
8169 struct io_ring_ctx
*ctx
= rsrc_data
->ctx
;
8170 struct io_rsrc_put
*prsrc
, *tmp
;
8172 list_for_each_entry_safe(prsrc
, tmp
, &ref_node
->rsrc_list
, list
) {
8173 list_del(&prsrc
->list
);
8176 bool lock_ring
= ctx
->flags
& IORING_SETUP_IOPOLL
;
8178 io_ring_submit_lock(ctx
, lock_ring
);
8179 spin_lock(&ctx
->completion_lock
);
8180 io_cqring_fill_event(ctx
, prsrc
->tag
, 0, 0);
8182 io_commit_cqring(ctx
);
8183 spin_unlock(&ctx
->completion_lock
);
8184 io_cqring_ev_posted(ctx
);
8185 io_ring_submit_unlock(ctx
, lock_ring
);
8188 rsrc_data
->do_put(ctx
, prsrc
);
8192 io_rsrc_node_destroy(ref_node
);
8193 if (atomic_dec_and_test(&rsrc_data
->refs
))
8194 complete(&rsrc_data
->done
);
8197 static void io_rsrc_put_work(struct work_struct
*work
)
8199 struct io_ring_ctx
*ctx
;
8200 struct llist_node
*node
;
8202 ctx
= container_of(work
, struct io_ring_ctx
, rsrc_put_work
.work
);
8203 node
= llist_del_all(&ctx
->rsrc_put_llist
);
8206 struct io_rsrc_node
*ref_node
;
8207 struct llist_node
*next
= node
->next
;
8209 ref_node
= llist_entry(node
, struct io_rsrc_node
, llist
);
8210 __io_rsrc_put_work(ref_node
);
8215 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8216 unsigned nr_args
, u64 __user
*tags
)
8218 __s32 __user
*fds
= (__s32 __user
*) arg
;
8227 if (nr_args
> IORING_MAX_FIXED_FILES
)
8229 if (nr_args
> rlimit(RLIMIT_NOFILE
))
8231 ret
= io_rsrc_node_switch_start(ctx
);
8234 ret
= io_rsrc_data_alloc(ctx
, io_rsrc_file_put
, tags
, nr_args
,
8240 if (!io_alloc_file_tables(&ctx
->file_table
, nr_args
))
8243 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
8244 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
8248 /* allow sparse sets */
8251 if (unlikely(*io_get_tag_slot(ctx
->file_data
, i
)))
8258 if (unlikely(!file
))
8262 * Don't allow io_uring instances to be registered. If UNIX
8263 * isn't enabled, then this causes a reference cycle and this
8264 * instance can never get freed. If UNIX is enabled we'll
8265 * handle it just fine, but there's still no point in allowing
8266 * a ring fd as it doesn't support regular read/write anyway.
8268 if (file
->f_op
== &io_uring_fops
) {
8272 io_fixed_file_set(io_fixed_file_slot(&ctx
->file_table
, i
), file
);
8275 ret
= io_sqe_files_scm(ctx
);
8277 __io_sqe_files_unregister(ctx
);
8281 io_rsrc_node_switch(ctx
, NULL
);
8284 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
8285 file
= io_file_from_index(ctx
, i
);
8289 io_free_file_tables(&ctx
->file_table
);
8290 ctx
->nr_user_files
= 0;
8292 io_rsrc_data_free(ctx
->file_data
);
8293 ctx
->file_data
= NULL
;
8297 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
8300 #if defined(CONFIG_UNIX)
8301 struct sock
*sock
= ctx
->ring_sock
->sk
;
8302 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
8303 struct sk_buff
*skb
;
8306 * See if we can merge this file into an existing skb SCM_RIGHTS
8307 * file set. If there's no room, fall back to allocating a new skb
8308 * and filling it in.
8310 spin_lock_irq(&head
->lock
);
8311 skb
= skb_peek(head
);
8313 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
8315 if (fpl
->count
< SCM_MAX_FD
) {
8316 __skb_unlink(skb
, head
);
8317 spin_unlock_irq(&head
->lock
);
8318 fpl
->fp
[fpl
->count
] = get_file(file
);
8319 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
8321 spin_lock_irq(&head
->lock
);
8322 __skb_queue_head(head
, skb
);
8327 spin_unlock_irq(&head
->lock
);
8334 return __io_sqe_files_scm(ctx
, 1, index
);
8340 static int io_queue_rsrc_removal(struct io_rsrc_data
*data
, unsigned idx
,
8341 struct io_rsrc_node
*node
, void *rsrc
)
8343 struct io_rsrc_put
*prsrc
;
8345 prsrc
= kzalloc(sizeof(*prsrc
), GFP_KERNEL
);
8349 prsrc
->tag
= *io_get_tag_slot(data
, idx
);
8351 list_add(&prsrc
->list
, &node
->rsrc_list
);
8355 static int io_install_fixed_file(struct io_kiocb
*req
, struct file
*file
,
8356 unsigned int issue_flags
, u32 slot_index
)
8358 struct io_ring_ctx
*ctx
= req
->ctx
;
8359 bool force_nonblock
= issue_flags
& IO_URING_F_NONBLOCK
;
8360 bool needs_switch
= false;
8361 struct io_fixed_file
*file_slot
;
8364 io_ring_submit_lock(ctx
, !force_nonblock
);
8365 if (file
->f_op
== &io_uring_fops
)
8368 if (!ctx
->file_data
)
8371 if (slot_index
>= ctx
->nr_user_files
)
8374 slot_index
= array_index_nospec(slot_index
, ctx
->nr_user_files
);
8375 file_slot
= io_fixed_file_slot(&ctx
->file_table
, slot_index
);
8377 if (file_slot
->file_ptr
) {
8378 struct file
*old_file
;
8380 ret
= io_rsrc_node_switch_start(ctx
);
8384 old_file
= (struct file
*)(file_slot
->file_ptr
& FFS_MASK
);
8385 ret
= io_queue_rsrc_removal(ctx
->file_data
, slot_index
,
8386 ctx
->rsrc_node
, old_file
);
8389 file_slot
->file_ptr
= 0;
8390 needs_switch
= true;
8393 *io_get_tag_slot(ctx
->file_data
, slot_index
) = 0;
8394 io_fixed_file_set(file_slot
, file
);
8395 ret
= io_sqe_file_register(ctx
, file
, slot_index
);
8397 file_slot
->file_ptr
= 0;
8404 io_rsrc_node_switch(ctx
, ctx
->file_data
);
8405 io_ring_submit_unlock(ctx
, !force_nonblock
);
8411 static int io_close_fixed(struct io_kiocb
*req
, unsigned int issue_flags
)
8413 unsigned int offset
= req
->close
.file_slot
- 1;
8414 struct io_ring_ctx
*ctx
= req
->ctx
;
8415 struct io_fixed_file
*file_slot
;
8419 io_ring_submit_lock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
8421 if (unlikely(!ctx
->file_data
))
8424 if (offset
>= ctx
->nr_user_files
)
8426 ret
= io_rsrc_node_switch_start(ctx
);
8430 i
= array_index_nospec(offset
, ctx
->nr_user_files
);
8431 file_slot
= io_fixed_file_slot(&ctx
->file_table
, i
);
8433 if (!file_slot
->file_ptr
)
8436 file
= (struct file
*)(file_slot
->file_ptr
& FFS_MASK
);
8437 ret
= io_queue_rsrc_removal(ctx
->file_data
, offset
, ctx
->rsrc_node
, file
);
8441 file_slot
->file_ptr
= 0;
8442 io_rsrc_node_switch(ctx
, ctx
->file_data
);
8445 io_ring_submit_unlock(ctx
, !(issue_flags
& IO_URING_F_NONBLOCK
));
8449 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
8450 struct io_uring_rsrc_update2
*up
,
8453 u64 __user
*tags
= u64_to_user_ptr(up
->tags
);
8454 __s32 __user
*fds
= u64_to_user_ptr(up
->data
);
8455 struct io_rsrc_data
*data
= ctx
->file_data
;
8456 struct io_fixed_file
*file_slot
;
8460 bool needs_switch
= false;
8462 if (!ctx
->file_data
)
8464 if (up
->offset
+ nr_args
> ctx
->nr_user_files
)
8467 for (done
= 0; done
< nr_args
; done
++) {
8470 if ((tags
&& copy_from_user(&tag
, &tags
[done
], sizeof(tag
))) ||
8471 copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
8475 if ((fd
== IORING_REGISTER_FILES_SKIP
|| fd
== -1) && tag
) {
8479 if (fd
== IORING_REGISTER_FILES_SKIP
)
8482 i
= array_index_nospec(up
->offset
+ done
, ctx
->nr_user_files
);
8483 file_slot
= io_fixed_file_slot(&ctx
->file_table
, i
);
8485 if (file_slot
->file_ptr
) {
8486 file
= (struct file
*)(file_slot
->file_ptr
& FFS_MASK
);
8487 err
= io_queue_rsrc_removal(data
, up
->offset
+ done
,
8488 ctx
->rsrc_node
, file
);
8491 file_slot
->file_ptr
= 0;
8492 needs_switch
= true;
8501 * Don't allow io_uring instances to be registered. If
8502 * UNIX isn't enabled, then this causes a reference
8503 * cycle and this instance can never get freed. If UNIX
8504 * is enabled we'll handle it just fine, but there's
8505 * still no point in allowing a ring fd as it doesn't
8506 * support regular read/write anyway.
8508 if (file
->f_op
== &io_uring_fops
) {
8513 *io_get_tag_slot(data
, up
->offset
+ done
) = tag
;
8514 io_fixed_file_set(file_slot
, file
);
8515 err
= io_sqe_file_register(ctx
, file
, i
);
8517 file_slot
->file_ptr
= 0;
8525 io_rsrc_node_switch(ctx
, data
);
8526 return done
? done
: err
;
8529 static struct io_wq
*io_init_wq_offload(struct io_ring_ctx
*ctx
,
8530 struct task_struct
*task
)
8532 struct io_wq_hash
*hash
;
8533 struct io_wq_data data
;
8534 unsigned int concurrency
;
8536 mutex_lock(&ctx
->uring_lock
);
8537 hash
= ctx
->hash_map
;
8539 hash
= kzalloc(sizeof(*hash
), GFP_KERNEL
);
8541 mutex_unlock(&ctx
->uring_lock
);
8542 return ERR_PTR(-ENOMEM
);
8544 refcount_set(&hash
->refs
, 1);
8545 init_waitqueue_head(&hash
->wait
);
8546 ctx
->hash_map
= hash
;
8548 mutex_unlock(&ctx
->uring_lock
);
8552 data
.free_work
= io_wq_free_work
;
8553 data
.do_work
= io_wq_submit_work
;
8555 /* Do QD, or 4 * CPUS, whatever is smallest */
8556 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
8558 return io_wq_create(concurrency
, &data
);
8561 static int io_uring_alloc_task_context(struct task_struct
*task
,
8562 struct io_ring_ctx
*ctx
)
8564 struct io_uring_task
*tctx
;
8567 tctx
= kzalloc(sizeof(*tctx
), GFP_KERNEL
);
8568 if (unlikely(!tctx
))
8571 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
8572 if (unlikely(ret
)) {
8577 tctx
->io_wq
= io_init_wq_offload(ctx
, task
);
8578 if (IS_ERR(tctx
->io_wq
)) {
8579 ret
= PTR_ERR(tctx
->io_wq
);
8580 percpu_counter_destroy(&tctx
->inflight
);
8586 init_waitqueue_head(&tctx
->wait
);
8587 atomic_set(&tctx
->in_idle
, 0);
8588 atomic_set(&tctx
->inflight_tracked
, 0);
8589 task
->io_uring
= tctx
;
8590 spin_lock_init(&tctx
->task_lock
);
8591 INIT_WQ_LIST(&tctx
->task_list
);
8592 init_task_work(&tctx
->task_work
, tctx_task_work
);
8596 void __io_uring_free(struct task_struct
*tsk
)
8598 struct io_uring_task
*tctx
= tsk
->io_uring
;
8600 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
8601 WARN_ON_ONCE(tctx
->io_wq
);
8602 WARN_ON_ONCE(tctx
->cached_refs
);
8604 percpu_counter_destroy(&tctx
->inflight
);
8606 tsk
->io_uring
= NULL
;
8609 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
8610 struct io_uring_params
*p
)
8614 /* Retain compatibility with failing for an invalid attach attempt */
8615 if ((ctx
->flags
& (IORING_SETUP_ATTACH_WQ
| IORING_SETUP_SQPOLL
)) ==
8616 IORING_SETUP_ATTACH_WQ
) {
8619 f
= fdget(p
->wq_fd
);
8622 if (f
.file
->f_op
!= &io_uring_fops
) {
8628 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8629 struct task_struct
*tsk
;
8630 struct io_sq_data
*sqd
;
8633 sqd
= io_get_sq_data(p
, &attached
);
8639 ctx
->sq_creds
= get_current_cred();
8641 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
8642 if (!ctx
->sq_thread_idle
)
8643 ctx
->sq_thread_idle
= HZ
;
8645 io_sq_thread_park(sqd
);
8646 list_add(&ctx
->sqd_list
, &sqd
->ctx_list
);
8647 io_sqd_update_thread_idle(sqd
);
8648 /* don't attach to a dying SQPOLL thread, would be racy */
8649 ret
= (attached
&& !sqd
->thread
) ? -ENXIO
: 0;
8650 io_sq_thread_unpark(sqd
);
8657 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8658 int cpu
= p
->sq_thread_cpu
;
8661 if (cpu
>= nr_cpu_ids
|| !cpu_online(cpu
))
8668 sqd
->task_pid
= current
->pid
;
8669 sqd
->task_tgid
= current
->tgid
;
8670 tsk
= create_io_thread(io_sq_thread
, sqd
, NUMA_NO_NODE
);
8677 ret
= io_uring_alloc_task_context(tsk
, ctx
);
8678 wake_up_new_task(tsk
);
8681 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
8682 /* Can't have SQ_AFF without SQPOLL */
8689 complete(&ctx
->sq_data
->exited
);
8691 io_sq_thread_finish(ctx
);
8695 static inline void __io_unaccount_mem(struct user_struct
*user
,
8696 unsigned long nr_pages
)
8698 atomic_long_sub(nr_pages
, &user
->locked_vm
);
8701 static inline int __io_account_mem(struct user_struct
*user
,
8702 unsigned long nr_pages
)
8704 unsigned long page_limit
, cur_pages
, new_pages
;
8706 /* Don't allow more pages than we can safely lock */
8707 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
8710 cur_pages
= atomic_long_read(&user
->locked_vm
);
8711 new_pages
= cur_pages
+ nr_pages
;
8712 if (new_pages
> page_limit
)
8714 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
8715 new_pages
) != cur_pages
);
8720 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8723 __io_unaccount_mem(ctx
->user
, nr_pages
);
8725 if (ctx
->mm_account
)
8726 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8729 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
)
8734 ret
= __io_account_mem(ctx
->user
, nr_pages
);
8739 if (ctx
->mm_account
)
8740 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
8745 static void io_mem_free(void *ptr
)
8752 page
= virt_to_head_page(ptr
);
8753 if (put_page_testzero(page
))
8754 free_compound_page(page
);
8757 static void *io_mem_alloc(size_t size
)
8759 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
8760 __GFP_NORETRY
| __GFP_ACCOUNT
;
8762 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
8765 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
8768 struct io_rings
*rings
;
8769 size_t off
, sq_array_size
;
8771 off
= struct_size(rings
, cqes
, cq_entries
);
8772 if (off
== SIZE_MAX
)
8776 off
= ALIGN(off
, SMP_CACHE_BYTES
);
8784 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
8785 if (sq_array_size
== SIZE_MAX
)
8788 if (check_add_overflow(off
, sq_array_size
, &off
))
8794 static void io_buffer_unmap(struct io_ring_ctx
*ctx
, struct io_mapped_ubuf
**slot
)
8796 struct io_mapped_ubuf
*imu
= *slot
;
8799 if (imu
!= ctx
->dummy_ubuf
) {
8800 for (i
= 0; i
< imu
->nr_bvecs
; i
++)
8801 unpin_user_page(imu
->bvec
[i
].bv_page
);
8802 if (imu
->acct_pages
)
8803 io_unaccount_mem(ctx
, imu
->acct_pages
);
8809 static void io_rsrc_buf_put(struct io_ring_ctx
*ctx
, struct io_rsrc_put
*prsrc
)
8811 io_buffer_unmap(ctx
, &prsrc
->buf
);
8815 static void __io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8819 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++)
8820 io_buffer_unmap(ctx
, &ctx
->user_bufs
[i
]);
8821 kfree(ctx
->user_bufs
);
8822 io_rsrc_data_free(ctx
->buf_data
);
8823 ctx
->user_bufs
= NULL
;
8824 ctx
->buf_data
= NULL
;
8825 ctx
->nr_user_bufs
= 0;
8828 static int io_sqe_buffers_unregister(struct io_ring_ctx
*ctx
)
8835 ret
= io_rsrc_ref_quiesce(ctx
->buf_data
, ctx
);
8837 __io_sqe_buffers_unregister(ctx
);
8841 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
8842 void __user
*arg
, unsigned index
)
8844 struct iovec __user
*src
;
8846 #ifdef CONFIG_COMPAT
8848 struct compat_iovec __user
*ciovs
;
8849 struct compat_iovec ciov
;
8851 ciovs
= (struct compat_iovec __user
*) arg
;
8852 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
8855 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
8856 dst
->iov_len
= ciov
.iov_len
;
8860 src
= (struct iovec __user
*) arg
;
8861 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8867 * Not super efficient, but this is just a registration time. And we do cache
8868 * the last compound head, so generally we'll only do a full search if we don't
8871 * We check if the given compound head page has already been accounted, to
8872 * avoid double accounting it. This allows us to account the full size of the
8873 * page, not just the constituent pages of a huge page.
8875 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8876 int nr_pages
, struct page
*hpage
)
8880 /* check current page array */
8881 for (i
= 0; i
< nr_pages
; i
++) {
8882 if (!PageCompound(pages
[i
]))
8884 if (compound_head(pages
[i
]) == hpage
)
8888 /* check previously registered pages */
8889 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8890 struct io_mapped_ubuf
*imu
= ctx
->user_bufs
[i
];
8892 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8893 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8895 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8903 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8904 int nr_pages
, struct io_mapped_ubuf
*imu
,
8905 struct page
**last_hpage
)
8909 imu
->acct_pages
= 0;
8910 for (i
= 0; i
< nr_pages
; i
++) {
8911 if (!PageCompound(pages
[i
])) {
8916 hpage
= compound_head(pages
[i
]);
8917 if (hpage
== *last_hpage
)
8919 *last_hpage
= hpage
;
8920 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8922 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8926 if (!imu
->acct_pages
)
8929 ret
= io_account_mem(ctx
, imu
->acct_pages
);
8931 imu
->acct_pages
= 0;
8935 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, struct iovec
*iov
,
8936 struct io_mapped_ubuf
**pimu
,
8937 struct page
**last_hpage
)
8939 struct io_mapped_ubuf
*imu
= NULL
;
8940 struct vm_area_struct
**vmas
= NULL
;
8941 struct page
**pages
= NULL
;
8942 unsigned long off
, start
, end
, ubuf
;
8944 int ret
, pret
, nr_pages
, i
;
8946 if (!iov
->iov_base
) {
8947 *pimu
= ctx
->dummy_ubuf
;
8951 ubuf
= (unsigned long) iov
->iov_base
;
8952 end
= (ubuf
+ iov
->iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8953 start
= ubuf
>> PAGE_SHIFT
;
8954 nr_pages
= end
- start
;
8959 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*), GFP_KERNEL
);
8963 vmas
= kvmalloc_array(nr_pages
, sizeof(struct vm_area_struct
*),
8968 imu
= kvmalloc(struct_size(imu
, bvec
, nr_pages
), GFP_KERNEL
);
8973 mmap_read_lock(current
->mm
);
8974 pret
= pin_user_pages(ubuf
, nr_pages
, FOLL_WRITE
| FOLL_LONGTERM
,
8976 if (pret
== nr_pages
) {
8977 /* don't support file backed memory */
8978 for (i
= 0; i
< nr_pages
; i
++) {
8979 struct vm_area_struct
*vma
= vmas
[i
];
8981 if (vma_is_shmem(vma
))
8984 !is_file_hugepages(vma
->vm_file
)) {
8990 ret
= pret
< 0 ? pret
: -EFAULT
;
8992 mmap_read_unlock(current
->mm
);
8995 * if we did partial map, or found file backed vmas,
8996 * release any pages we did get
8999 unpin_user_pages(pages
, pret
);
9003 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, last_hpage
);
9005 unpin_user_pages(pages
, pret
);
9009 off
= ubuf
& ~PAGE_MASK
;
9010 size
= iov
->iov_len
;
9011 for (i
= 0; i
< nr_pages
; i
++) {
9014 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
9015 imu
->bvec
[i
].bv_page
= pages
[i
];
9016 imu
->bvec
[i
].bv_len
= vec_len
;
9017 imu
->bvec
[i
].bv_offset
= off
;
9021 /* store original address for later verification */
9023 imu
->ubuf_end
= ubuf
+ iov
->iov_len
;
9024 imu
->nr_bvecs
= nr_pages
;
9035 static int io_buffers_map_alloc(struct io_ring_ctx
*ctx
, unsigned int nr_args
)
9037 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(*ctx
->user_bufs
), GFP_KERNEL
);
9038 return ctx
->user_bufs
? 0 : -ENOMEM
;
9041 static int io_buffer_validate(struct iovec
*iov
)
9043 unsigned long tmp
, acct_len
= iov
->iov_len
+ (PAGE_SIZE
- 1);
9046 * Don't impose further limits on the size and buffer
9047 * constraints here, we'll -EINVAL later when IO is
9048 * submitted if they are wrong.
9051 return iov
->iov_len
? -EFAULT
: 0;
9055 /* arbitrary limit, but we need something */
9056 if (iov
->iov_len
> SZ_1G
)
9059 if (check_add_overflow((unsigned long)iov
->iov_base
, acct_len
, &tmp
))
9065 static int io_sqe_buffers_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
9066 unsigned int nr_args
, u64 __user
*tags
)
9068 struct page
*last_hpage
= NULL
;
9069 struct io_rsrc_data
*data
;
9075 if (!nr_args
|| nr_args
> IORING_MAX_REG_BUFFERS
)
9077 ret
= io_rsrc_node_switch_start(ctx
);
9080 ret
= io_rsrc_data_alloc(ctx
, io_rsrc_buf_put
, tags
, nr_args
, &data
);
9083 ret
= io_buffers_map_alloc(ctx
, nr_args
);
9085 io_rsrc_data_free(data
);
9089 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_bufs
++) {
9090 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
9093 ret
= io_buffer_validate(&iov
);
9096 if (!iov
.iov_base
&& *io_get_tag_slot(data
, i
)) {
9101 ret
= io_sqe_buffer_register(ctx
, &iov
, &ctx
->user_bufs
[i
],
9107 WARN_ON_ONCE(ctx
->buf_data
);
9109 ctx
->buf_data
= data
;
9111 __io_sqe_buffers_unregister(ctx
);
9113 io_rsrc_node_switch(ctx
, NULL
);
9117 static int __io_sqe_buffers_update(struct io_ring_ctx
*ctx
,
9118 struct io_uring_rsrc_update2
*up
,
9119 unsigned int nr_args
)
9121 u64 __user
*tags
= u64_to_user_ptr(up
->tags
);
9122 struct iovec iov
, __user
*iovs
= u64_to_user_ptr(up
->data
);
9123 struct page
*last_hpage
= NULL
;
9124 bool needs_switch
= false;
9130 if (up
->offset
+ nr_args
> ctx
->nr_user_bufs
)
9133 for (done
= 0; done
< nr_args
; done
++) {
9134 struct io_mapped_ubuf
*imu
;
9135 int offset
= up
->offset
+ done
;
9138 err
= io_copy_iov(ctx
, &iov
, iovs
, done
);
9141 if (tags
&& copy_from_user(&tag
, &tags
[done
], sizeof(tag
))) {
9145 err
= io_buffer_validate(&iov
);
9148 if (!iov
.iov_base
&& tag
) {
9152 err
= io_sqe_buffer_register(ctx
, &iov
, &imu
, &last_hpage
);
9156 i
= array_index_nospec(offset
, ctx
->nr_user_bufs
);
9157 if (ctx
->user_bufs
[i
] != ctx
->dummy_ubuf
) {
9158 err
= io_queue_rsrc_removal(ctx
->buf_data
, offset
,
9159 ctx
->rsrc_node
, ctx
->user_bufs
[i
]);
9160 if (unlikely(err
)) {
9161 io_buffer_unmap(ctx
, &imu
);
9164 ctx
->user_bufs
[i
] = NULL
;
9165 needs_switch
= true;
9168 ctx
->user_bufs
[i
] = imu
;
9169 *io_get_tag_slot(ctx
->buf_data
, offset
) = tag
;
9173 io_rsrc_node_switch(ctx
, ctx
->buf_data
);
9174 return done
? done
: err
;
9177 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
9179 __s32 __user
*fds
= arg
;
9185 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
9188 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
9189 if (IS_ERR(ctx
->cq_ev_fd
)) {
9190 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
9192 ctx
->cq_ev_fd
= NULL
;
9199 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
9201 if (ctx
->cq_ev_fd
) {
9202 eventfd_ctx_put(ctx
->cq_ev_fd
);
9203 ctx
->cq_ev_fd
= NULL
;
9210 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
9212 struct io_buffer
*buf
;
9213 unsigned long index
;
9215 xa_for_each(&ctx
->io_buffers
, index
, buf
) {
9216 __io_remove_buffers(ctx
, buf
, index
, -1U);
9221 static void io_req_cache_free(struct list_head
*list
)
9223 struct io_kiocb
*req
, *nxt
;
9225 list_for_each_entry_safe(req
, nxt
, list
, inflight_entry
) {
9226 list_del(&req
->inflight_entry
);
9227 kmem_cache_free(req_cachep
, req
);
9231 static void io_req_caches_free(struct io_ring_ctx
*ctx
)
9233 struct io_submit_state
*state
= &ctx
->submit_state
;
9235 mutex_lock(&ctx
->uring_lock
);
9237 if (state
->free_reqs
) {
9238 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
9239 state
->free_reqs
= 0;
9242 io_flush_cached_locked_reqs(ctx
, state
);
9243 io_req_cache_free(&state
->free_list
);
9244 mutex_unlock(&ctx
->uring_lock
);
9247 static void io_wait_rsrc_data(struct io_rsrc_data
*data
)
9249 if (data
&& !atomic_dec_and_test(&data
->refs
))
9250 wait_for_completion(&data
->done
);
9253 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
9255 io_sq_thread_finish(ctx
);
9257 if (ctx
->mm_account
) {
9258 mmdrop(ctx
->mm_account
);
9259 ctx
->mm_account
= NULL
;
9262 /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */
9263 io_wait_rsrc_data(ctx
->buf_data
);
9264 io_wait_rsrc_data(ctx
->file_data
);
9266 mutex_lock(&ctx
->uring_lock
);
9268 __io_sqe_buffers_unregister(ctx
);
9270 __io_sqe_files_unregister(ctx
);
9272 __io_cqring_overflow_flush(ctx
, true);
9273 mutex_unlock(&ctx
->uring_lock
);
9274 io_eventfd_unregister(ctx
);
9275 io_destroy_buffers(ctx
);
9277 put_cred(ctx
->sq_creds
);
9279 /* there are no registered resources left, nobody uses it */
9281 io_rsrc_node_destroy(ctx
->rsrc_node
);
9282 if (ctx
->rsrc_backup_node
)
9283 io_rsrc_node_destroy(ctx
->rsrc_backup_node
);
9284 flush_delayed_work(&ctx
->rsrc_put_work
);
9286 WARN_ON_ONCE(!list_empty(&ctx
->rsrc_ref_list
));
9287 WARN_ON_ONCE(!llist_empty(&ctx
->rsrc_put_llist
));
9289 #if defined(CONFIG_UNIX)
9290 if (ctx
->ring_sock
) {
9291 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
9292 sock_release(ctx
->ring_sock
);
9295 WARN_ON_ONCE(!list_empty(&ctx
->ltimeout_list
));
9297 io_mem_free(ctx
->rings
);
9298 io_mem_free(ctx
->sq_sqes
);
9300 percpu_ref_exit(&ctx
->refs
);
9301 free_uid(ctx
->user
);
9302 io_req_caches_free(ctx
);
9304 io_wq_put_hash(ctx
->hash_map
);
9305 kfree(ctx
->cancel_hash
);
9306 kfree(ctx
->dummy_ubuf
);
9310 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
9312 struct io_ring_ctx
*ctx
= file
->private_data
;
9315 poll_wait(file
, &ctx
->poll_wait
, wait
);
9317 * synchronizes with barrier from wq_has_sleeper call in
9321 if (!io_sqring_full(ctx
))
9322 mask
|= EPOLLOUT
| EPOLLWRNORM
;
9325 * Don't flush cqring overflow list here, just do a simple check.
9326 * Otherwise there could possible be ABBA deadlock:
9329 * lock(&ctx->uring_lock);
9331 * lock(&ctx->uring_lock);
9334 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
9335 * pushs them to do the flush.
9337 if (io_cqring_events(ctx
) || test_bit(0, &ctx
->check_cq_overflow
))
9338 mask
|= EPOLLIN
| EPOLLRDNORM
;
9343 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
9345 const struct cred
*creds
;
9347 creds
= xa_erase(&ctx
->personalities
, id
);
9356 struct io_tctx_exit
{
9357 struct callback_head task_work
;
9358 struct completion completion
;
9359 struct io_ring_ctx
*ctx
;
9362 static void io_tctx_exit_cb(struct callback_head
*cb
)
9364 struct io_uring_task
*tctx
= current
->io_uring
;
9365 struct io_tctx_exit
*work
;
9367 work
= container_of(cb
, struct io_tctx_exit
, task_work
);
9369 * When @in_idle, we're in cancellation and it's racy to remove the
9370 * node. It'll be removed by the end of cancellation, just ignore it.
9372 if (!atomic_read(&tctx
->in_idle
))
9373 io_uring_del_tctx_node((unsigned long)work
->ctx
);
9374 complete(&work
->completion
);
9377 static bool io_cancel_ctx_cb(struct io_wq_work
*work
, void *data
)
9379 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
9381 return req
->ctx
== data
;
9384 static void io_ring_exit_work(struct work_struct
*work
)
9386 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
, exit_work
);
9387 unsigned long timeout
= jiffies
+ HZ
* 60 * 5;
9388 unsigned long interval
= HZ
/ 20;
9389 struct io_tctx_exit exit
;
9390 struct io_tctx_node
*node
;
9394 * If we're doing polled IO and end up having requests being
9395 * submitted async (out-of-line), then completions can come in while
9396 * we're waiting for refs to drop. We need to reap these manually,
9397 * as nobody else will be looking for them.
9400 io_uring_try_cancel_requests(ctx
, NULL
, true);
9402 struct io_sq_data
*sqd
= ctx
->sq_data
;
9403 struct task_struct
*tsk
;
9405 io_sq_thread_park(sqd
);
9407 if (tsk
&& tsk
->io_uring
&& tsk
->io_uring
->io_wq
)
9408 io_wq_cancel_cb(tsk
->io_uring
->io_wq
,
9409 io_cancel_ctx_cb
, ctx
, true);
9410 io_sq_thread_unpark(sqd
);
9413 if (WARN_ON_ONCE(time_after(jiffies
, timeout
))) {
9414 /* there is little hope left, don't run it too often */
9417 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, interval
));
9419 init_completion(&exit
.completion
);
9420 init_task_work(&exit
.task_work
, io_tctx_exit_cb
);
9423 * Some may use context even when all refs and requests have been put,
9424 * and they are free to do so while still holding uring_lock or
9425 * completion_lock, see io_req_task_submit(). Apart from other work,
9426 * this lock/unlock section also waits them to finish.
9428 mutex_lock(&ctx
->uring_lock
);
9429 while (!list_empty(&ctx
->tctx_list
)) {
9430 WARN_ON_ONCE(time_after(jiffies
, timeout
));
9432 node
= list_first_entry(&ctx
->tctx_list
, struct io_tctx_node
,
9434 /* don't spin on a single task if cancellation failed */
9435 list_rotate_left(&ctx
->tctx_list
);
9436 ret
= task_work_add(node
->task
, &exit
.task_work
, TWA_SIGNAL
);
9437 if (WARN_ON_ONCE(ret
))
9439 wake_up_process(node
->task
);
9441 mutex_unlock(&ctx
->uring_lock
);
9442 wait_for_completion(&exit
.completion
);
9443 mutex_lock(&ctx
->uring_lock
);
9445 mutex_unlock(&ctx
->uring_lock
);
9446 spin_lock(&ctx
->completion_lock
);
9447 spin_unlock(&ctx
->completion_lock
);
9449 io_ring_ctx_free(ctx
);
9452 /* Returns true if we found and killed one or more timeouts */
9453 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
,
9456 struct io_kiocb
*req
, *tmp
;
9459 spin_lock(&ctx
->completion_lock
);
9460 spin_lock_irq(&ctx
->timeout_lock
);
9461 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
9462 if (io_match_task(req
, tsk
, cancel_all
)) {
9463 io_kill_timeout(req
, -ECANCELED
);
9467 spin_unlock_irq(&ctx
->timeout_lock
);
9469 io_commit_cqring(ctx
);
9470 spin_unlock(&ctx
->completion_lock
);
9472 io_cqring_ev_posted(ctx
);
9473 return canceled
!= 0;
9476 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
9478 unsigned long index
;
9479 struct creds
*creds
;
9481 mutex_lock(&ctx
->uring_lock
);
9482 percpu_ref_kill(&ctx
->refs
);
9484 __io_cqring_overflow_flush(ctx
, true);
9485 xa_for_each(&ctx
->personalities
, index
, creds
)
9486 io_unregister_personality(ctx
, index
);
9487 mutex_unlock(&ctx
->uring_lock
);
9489 io_kill_timeouts(ctx
, NULL
, true);
9490 io_poll_remove_all(ctx
, NULL
, true);
9492 /* if we failed setting up the ctx, we might not have any rings */
9493 io_iopoll_try_reap_events(ctx
);
9495 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
9497 * Use system_unbound_wq to avoid spawning tons of event kworkers
9498 * if we're exiting a ton of rings at the same time. It just adds
9499 * noise and overhead, there's no discernable change in runtime
9500 * over using system_wq.
9502 queue_work(system_unbound_wq
, &ctx
->exit_work
);
9505 static int io_uring_release(struct inode
*inode
, struct file
*file
)
9507 struct io_ring_ctx
*ctx
= file
->private_data
;
9509 file
->private_data
= NULL
;
9510 io_ring_ctx_wait_and_kill(ctx
);
9514 struct io_task_cancel
{
9515 struct task_struct
*task
;
9519 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
9521 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
9522 struct io_task_cancel
*cancel
= data
;
9525 if (!cancel
->all
&& (req
->flags
& REQ_F_LINK_TIMEOUT
)) {
9526 struct io_ring_ctx
*ctx
= req
->ctx
;
9528 /* protect against races with linked timeouts */
9529 spin_lock(&ctx
->completion_lock
);
9530 ret
= io_match_task(req
, cancel
->task
, cancel
->all
);
9531 spin_unlock(&ctx
->completion_lock
);
9533 ret
= io_match_task(req
, cancel
->task
, cancel
->all
);
9538 static bool io_cancel_defer_files(struct io_ring_ctx
*ctx
,
9539 struct task_struct
*task
, bool cancel_all
)
9541 struct io_defer_entry
*de
;
9544 spin_lock(&ctx
->completion_lock
);
9545 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
9546 if (io_match_task(de
->req
, task
, cancel_all
)) {
9547 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
9551 spin_unlock(&ctx
->completion_lock
);
9552 if (list_empty(&list
))
9555 while (!list_empty(&list
)) {
9556 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
9557 list_del_init(&de
->list
);
9558 io_req_complete_failed(de
->req
, -ECANCELED
);
9564 static bool io_uring_try_cancel_iowq(struct io_ring_ctx
*ctx
)
9566 struct io_tctx_node
*node
;
9567 enum io_wq_cancel cret
;
9570 mutex_lock(&ctx
->uring_lock
);
9571 list_for_each_entry(node
, &ctx
->tctx_list
, ctx_node
) {
9572 struct io_uring_task
*tctx
= node
->task
->io_uring
;
9575 * io_wq will stay alive while we hold uring_lock, because it's
9576 * killed after ctx nodes, which requires to take the lock.
9578 if (!tctx
|| !tctx
->io_wq
)
9580 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_ctx_cb
, ctx
, true);
9581 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
9583 mutex_unlock(&ctx
->uring_lock
);
9588 static void io_uring_try_cancel_requests(struct io_ring_ctx
*ctx
,
9589 struct task_struct
*task
,
9592 struct io_task_cancel cancel
= { .task
= task
, .all
= cancel_all
, };
9593 struct io_uring_task
*tctx
= task
? task
->io_uring
: NULL
;
9596 enum io_wq_cancel cret
;
9600 ret
|= io_uring_try_cancel_iowq(ctx
);
9601 } else if (tctx
&& tctx
->io_wq
) {
9603 * Cancels requests of all rings, not only @ctx, but
9604 * it's fine as the task is in exit/exec.
9606 cret
= io_wq_cancel_cb(tctx
->io_wq
, io_cancel_task_cb
,
9608 ret
|= (cret
!= IO_WQ_CANCEL_NOTFOUND
);
9611 /* SQPOLL thread does its own polling */
9612 if ((!(ctx
->flags
& IORING_SETUP_SQPOLL
) && cancel_all
) ||
9613 (ctx
->sq_data
&& ctx
->sq_data
->thread
== current
)) {
9614 while (!list_empty_careful(&ctx
->iopoll_list
)) {
9615 io_iopoll_try_reap_events(ctx
);
9620 ret
|= io_cancel_defer_files(ctx
, task
, cancel_all
);
9621 ret
|= io_poll_remove_all(ctx
, task
, cancel_all
);
9622 ret
|= io_kill_timeouts(ctx
, task
, cancel_all
);
9624 ret
|= io_run_task_work();
9631 static int __io_uring_add_tctx_node(struct io_ring_ctx
*ctx
)
9633 struct io_uring_task
*tctx
= current
->io_uring
;
9634 struct io_tctx_node
*node
;
9637 if (unlikely(!tctx
)) {
9638 ret
= io_uring_alloc_task_context(current
, ctx
);
9641 tctx
= current
->io_uring
;
9643 if (!xa_load(&tctx
->xa
, (unsigned long)ctx
)) {
9644 node
= kmalloc(sizeof(*node
), GFP_KERNEL
);
9648 node
->task
= current
;
9650 ret
= xa_err(xa_store(&tctx
->xa
, (unsigned long)ctx
,
9657 mutex_lock(&ctx
->uring_lock
);
9658 list_add(&node
->ctx_node
, &ctx
->tctx_list
);
9659 mutex_unlock(&ctx
->uring_lock
);
9666 * Note that this task has used io_uring. We use it for cancelation purposes.
9668 static inline int io_uring_add_tctx_node(struct io_ring_ctx
*ctx
)
9670 struct io_uring_task
*tctx
= current
->io_uring
;
9672 if (likely(tctx
&& tctx
->last
== ctx
))
9674 return __io_uring_add_tctx_node(ctx
);
9678 * Remove this io_uring_file -> task mapping.
9680 static void io_uring_del_tctx_node(unsigned long index
)
9682 struct io_uring_task
*tctx
= current
->io_uring
;
9683 struct io_tctx_node
*node
;
9687 node
= xa_erase(&tctx
->xa
, index
);
9691 WARN_ON_ONCE(current
!= node
->task
);
9692 WARN_ON_ONCE(list_empty(&node
->ctx_node
));
9694 mutex_lock(&node
->ctx
->uring_lock
);
9695 list_del(&node
->ctx_node
);
9696 mutex_unlock(&node
->ctx
->uring_lock
);
9698 if (tctx
->last
== node
->ctx
)
9703 static void io_uring_clean_tctx(struct io_uring_task
*tctx
)
9705 struct io_wq
*wq
= tctx
->io_wq
;
9706 struct io_tctx_node
*node
;
9707 unsigned long index
;
9709 xa_for_each(&tctx
->xa
, index
, node
) {
9710 io_uring_del_tctx_node(index
);
9715 * Must be after io_uring_del_task_file() (removes nodes under
9716 * uring_lock) to avoid race with io_uring_try_cancel_iowq().
9718 io_wq_put_and_exit(wq
);
9723 static s64
tctx_inflight(struct io_uring_task
*tctx
, bool tracked
)
9726 return atomic_read(&tctx
->inflight_tracked
);
9727 return percpu_counter_sum(&tctx
->inflight
);
9730 static void io_uring_drop_tctx_refs(struct task_struct
*task
)
9732 struct io_uring_task
*tctx
= task
->io_uring
;
9733 unsigned int refs
= tctx
->cached_refs
;
9736 tctx
->cached_refs
= 0;
9737 percpu_counter_sub(&tctx
->inflight
, refs
);
9738 put_task_struct_many(task
, refs
);
9743 * Find any io_uring ctx that this task has registered or done IO on, and cancel
9744 * requests. @sqd should be not-null IIF it's an SQPOLL thread cancellation.
9746 static void io_uring_cancel_generic(bool cancel_all
, struct io_sq_data
*sqd
)
9748 struct io_uring_task
*tctx
= current
->io_uring
;
9749 struct io_ring_ctx
*ctx
;
9753 WARN_ON_ONCE(sqd
&& sqd
->thread
!= current
);
9755 if (!current
->io_uring
)
9758 io_wq_exit_start(tctx
->io_wq
);
9760 atomic_inc(&tctx
->in_idle
);
9762 io_uring_drop_tctx_refs(current
);
9763 /* read completions before cancelations */
9764 inflight
= tctx_inflight(tctx
, !cancel_all
);
9769 struct io_tctx_node
*node
;
9770 unsigned long index
;
9772 xa_for_each(&tctx
->xa
, index
, node
) {
9773 /* sqpoll task will cancel all its requests */
9774 if (node
->ctx
->sq_data
)
9776 io_uring_try_cancel_requests(node
->ctx
, current
,
9780 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
9781 io_uring_try_cancel_requests(ctx
, current
,
9785 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
9786 io_uring_drop_tctx_refs(current
);
9788 * If we've seen completions, retry without waiting. This
9789 * avoids a race where a completion comes in before we did
9790 * prepare_to_wait().
9792 if (inflight
== tctx_inflight(tctx
, !cancel_all
))
9794 finish_wait(&tctx
->wait
, &wait
);
9796 atomic_dec(&tctx
->in_idle
);
9798 io_uring_clean_tctx(tctx
);
9800 /* for exec all current's requests should be gone, kill tctx */
9801 __io_uring_free(current
);
9805 void __io_uring_cancel(bool cancel_all
)
9807 io_uring_cancel_generic(cancel_all
, NULL
);
9810 static void *io_uring_validate_mmap_request(struct file
*file
,
9811 loff_t pgoff
, size_t sz
)
9813 struct io_ring_ctx
*ctx
= file
->private_data
;
9814 loff_t offset
= pgoff
<< PAGE_SHIFT
;
9819 case IORING_OFF_SQ_RING
:
9820 case IORING_OFF_CQ_RING
:
9823 case IORING_OFF_SQES
:
9827 return ERR_PTR(-EINVAL
);
9830 page
= virt_to_head_page(ptr
);
9831 if (sz
> page_size(page
))
9832 return ERR_PTR(-EINVAL
);
9839 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9841 size_t sz
= vma
->vm_end
- vma
->vm_start
;
9845 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
9847 return PTR_ERR(ptr
);
9849 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
9850 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
9853 #else /* !CONFIG_MMU */
9855 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
9857 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
9860 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
9862 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
9865 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
9866 unsigned long addr
, unsigned long len
,
9867 unsigned long pgoff
, unsigned long flags
)
9871 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
9873 return PTR_ERR(ptr
);
9875 return (unsigned long) ptr
;
9878 #endif /* !CONFIG_MMU */
9880 static int io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
9885 if (!io_sqring_full(ctx
))
9887 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
9889 if (!io_sqring_full(ctx
))
9892 } while (!signal_pending(current
));
9894 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
9898 static int io_get_ext_arg(unsigned flags
, const void __user
*argp
, size_t *argsz
,
9899 struct __kernel_timespec __user
**ts
,
9900 const sigset_t __user
**sig
)
9902 struct io_uring_getevents_arg arg
;
9905 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9906 * is just a pointer to the sigset_t.
9908 if (!(flags
& IORING_ENTER_EXT_ARG
)) {
9909 *sig
= (const sigset_t __user
*) argp
;
9915 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9916 * timespec and sigset_t pointers if good.
9918 if (*argsz
!= sizeof(arg
))
9920 if (copy_from_user(&arg
, argp
, sizeof(arg
)))
9922 *sig
= u64_to_user_ptr(arg
.sigmask
);
9923 *argsz
= arg
.sigmask_sz
;
9924 *ts
= u64_to_user_ptr(arg
.ts
);
9928 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
9929 u32
, min_complete
, u32
, flags
, const void __user
*, argp
,
9932 struct io_ring_ctx
*ctx
;
9939 if (unlikely(flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
9940 IORING_ENTER_SQ_WAIT
| IORING_ENTER_EXT_ARG
)))
9944 if (unlikely(!f
.file
))
9948 if (unlikely(f
.file
->f_op
!= &io_uring_fops
))
9952 ctx
= f
.file
->private_data
;
9953 if (unlikely(!percpu_ref_tryget(&ctx
->refs
)))
9957 if (unlikely(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9961 * For SQ polling, the thread will do all submissions and completions.
9962 * Just return the requested submit count, and wake the thread if
9966 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
9967 io_cqring_overflow_flush(ctx
);
9969 if (unlikely(ctx
->sq_data
->thread
== NULL
)) {
9973 if (flags
& IORING_ENTER_SQ_WAKEUP
)
9974 wake_up(&ctx
->sq_data
->wait
);
9975 if (flags
& IORING_ENTER_SQ_WAIT
) {
9976 ret
= io_sqpoll_wait_sq(ctx
);
9980 submitted
= to_submit
;
9981 } else if (to_submit
) {
9982 ret
= io_uring_add_tctx_node(ctx
);
9985 mutex_lock(&ctx
->uring_lock
);
9986 submitted
= io_submit_sqes(ctx
, to_submit
);
9987 mutex_unlock(&ctx
->uring_lock
);
9989 if (submitted
!= to_submit
)
9992 if (flags
& IORING_ENTER_GETEVENTS
) {
9993 const sigset_t __user
*sig
;
9994 struct __kernel_timespec __user
*ts
;
9996 ret
= io_get_ext_arg(flags
, argp
, &argsz
, &ts
, &sig
);
10000 min_complete
= min(min_complete
, ctx
->cq_entries
);
10003 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
10004 * space applications don't need to do io completion events
10005 * polling again, they can rely on io_sq_thread to do polling
10006 * work, which can reduce cpu usage and uring_lock contention.
10008 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
10009 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
10010 ret
= io_iopoll_check(ctx
, min_complete
);
10012 ret
= io_cqring_wait(ctx
, min_complete
, sig
, argsz
, ts
);
10017 percpu_ref_put(&ctx
->refs
);
10020 return submitted
? submitted
: ret
;
10023 #ifdef CONFIG_PROC_FS
10024 static int io_uring_show_cred(struct seq_file
*m
, unsigned int id
,
10025 const struct cred
*cred
)
10027 struct user_namespace
*uns
= seq_user_ns(m
);
10028 struct group_info
*gi
;
10033 seq_printf(m
, "%5d\n", id
);
10034 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
10035 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
10036 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
10037 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
10038 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
10039 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
10040 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
10041 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
10042 seq_puts(m
, "\n\tGroups:\t");
10043 gi
= cred
->group_info
;
10044 for (g
= 0; g
< gi
->ngroups
; g
++) {
10045 seq_put_decimal_ull(m
, g
? " " : "",
10046 from_kgid_munged(uns
, gi
->gid
[g
]));
10048 seq_puts(m
, "\n\tCapEff:\t");
10049 cap
= cred
->cap_effective
;
10050 CAP_FOR_EACH_U32(__capi
)
10051 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
10056 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
10058 struct io_sq_data
*sq
= NULL
;
10063 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
10064 * since fdinfo case grabs it in the opposite direction of normal use
10065 * cases. If we fail to get the lock, we just don't iterate any
10066 * structures that could be going away outside the io_uring mutex.
10068 has_lock
= mutex_trylock(&ctx
->uring_lock
);
10070 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
)) {
10076 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
10077 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
10078 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
10079 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
10080 struct file
*f
= io_file_from_index(ctx
, i
);
10083 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
10085 seq_printf(m
, "%5u: <none>\n", i
);
10087 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
10088 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
10089 struct io_mapped_ubuf
*buf
= ctx
->user_bufs
[i
];
10090 unsigned int len
= buf
->ubuf_end
- buf
->ubuf
;
10092 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
, len
);
10094 if (has_lock
&& !xa_empty(&ctx
->personalities
)) {
10095 unsigned long index
;
10096 const struct cred
*cred
;
10098 seq_printf(m
, "Personalities:\n");
10099 xa_for_each(&ctx
->personalities
, index
, cred
)
10100 io_uring_show_cred(m
, index
, cred
);
10102 seq_printf(m
, "PollList:\n");
10103 spin_lock(&ctx
->completion_lock
);
10104 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
10105 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
10106 struct io_kiocb
*req
;
10108 hlist_for_each_entry(req
, list
, hash_node
)
10109 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
10110 req
->task
->task_works
!= NULL
);
10112 spin_unlock(&ctx
->completion_lock
);
10114 mutex_unlock(&ctx
->uring_lock
);
10117 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
10119 struct io_ring_ctx
*ctx
= f
->private_data
;
10121 if (percpu_ref_tryget(&ctx
->refs
)) {
10122 __io_uring_show_fdinfo(ctx
, m
);
10123 percpu_ref_put(&ctx
->refs
);
10128 static const struct file_operations io_uring_fops
= {
10129 .release
= io_uring_release
,
10130 .mmap
= io_uring_mmap
,
10132 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
10133 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
10135 .poll
= io_uring_poll
,
10136 #ifdef CONFIG_PROC_FS
10137 .show_fdinfo
= io_uring_show_fdinfo
,
10141 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
10142 struct io_uring_params
*p
)
10144 struct io_rings
*rings
;
10145 size_t size
, sq_array_offset
;
10147 /* make sure these are sane, as we already accounted them */
10148 ctx
->sq_entries
= p
->sq_entries
;
10149 ctx
->cq_entries
= p
->cq_entries
;
10151 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
10152 if (size
== SIZE_MAX
)
10155 rings
= io_mem_alloc(size
);
10159 ctx
->rings
= rings
;
10160 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
10161 rings
->sq_ring_mask
= p
->sq_entries
- 1;
10162 rings
->cq_ring_mask
= p
->cq_entries
- 1;
10163 rings
->sq_ring_entries
= p
->sq_entries
;
10164 rings
->cq_ring_entries
= p
->cq_entries
;
10166 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
10167 if (size
== SIZE_MAX
) {
10168 io_mem_free(ctx
->rings
);
10173 ctx
->sq_sqes
= io_mem_alloc(size
);
10174 if (!ctx
->sq_sqes
) {
10175 io_mem_free(ctx
->rings
);
10183 static int io_uring_install_fd(struct io_ring_ctx
*ctx
, struct file
*file
)
10187 fd
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
10191 ret
= io_uring_add_tctx_node(ctx
);
10196 fd_install(fd
, file
);
10201 * Allocate an anonymous fd, this is what constitutes the application
10202 * visible backing of an io_uring instance. The application mmaps this
10203 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
10204 * we have to tie this fd to a socket for file garbage collection purposes.
10206 static struct file
*io_uring_get_file(struct io_ring_ctx
*ctx
)
10209 #if defined(CONFIG_UNIX)
10212 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
10215 return ERR_PTR(ret
);
10218 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
10219 O_RDWR
| O_CLOEXEC
);
10220 #if defined(CONFIG_UNIX)
10221 if (IS_ERR(file
)) {
10222 sock_release(ctx
->ring_sock
);
10223 ctx
->ring_sock
= NULL
;
10225 ctx
->ring_sock
->file
= file
;
10231 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
10232 struct io_uring_params __user
*params
)
10234 struct io_ring_ctx
*ctx
;
10240 if (entries
> IORING_MAX_ENTRIES
) {
10241 if (!(p
->flags
& IORING_SETUP_CLAMP
))
10243 entries
= IORING_MAX_ENTRIES
;
10247 * Use twice as many entries for the CQ ring. It's possible for the
10248 * application to drive a higher depth than the size of the SQ ring,
10249 * since the sqes are only used at submission time. This allows for
10250 * some flexibility in overcommitting a bit. If the application has
10251 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
10252 * of CQ ring entries manually.
10254 p
->sq_entries
= roundup_pow_of_two(entries
);
10255 if (p
->flags
& IORING_SETUP_CQSIZE
) {
10257 * If IORING_SETUP_CQSIZE is set, we do the same roundup
10258 * to a power-of-two, if it isn't already. We do NOT impose
10259 * any cq vs sq ring sizing.
10261 if (!p
->cq_entries
)
10263 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
10264 if (!(p
->flags
& IORING_SETUP_CLAMP
))
10266 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
10268 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
10269 if (p
->cq_entries
< p
->sq_entries
)
10272 p
->cq_entries
= 2 * p
->sq_entries
;
10275 ctx
= io_ring_ctx_alloc(p
);
10278 ctx
->compat
= in_compat_syscall();
10279 if (!capable(CAP_IPC_LOCK
))
10280 ctx
->user
= get_uid(current_user());
10283 * This is just grabbed for accounting purposes. When a process exits,
10284 * the mm is exited and dropped before the files, hence we need to hang
10285 * on to this mm purely for the purposes of being able to unaccount
10286 * memory (locked/pinned vm). It's not used for anything else.
10288 mmgrab(current
->mm
);
10289 ctx
->mm_account
= current
->mm
;
10291 ret
= io_allocate_scq_urings(ctx
, p
);
10295 ret
= io_sq_offload_create(ctx
, p
);
10298 /* always set a rsrc node */
10299 ret
= io_rsrc_node_switch_start(ctx
);
10302 io_rsrc_node_switch(ctx
, NULL
);
10304 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
10305 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
10306 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
10307 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
10308 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
10309 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
10310 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
10311 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
10313 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
10314 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
10315 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
10316 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
10317 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
10318 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
10319 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
10320 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
10322 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
10323 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
10324 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
10325 IORING_FEAT_POLL_32BITS
| IORING_FEAT_SQPOLL_NONFIXED
|
10326 IORING_FEAT_EXT_ARG
| IORING_FEAT_NATIVE_WORKERS
|
10327 IORING_FEAT_RSRC_TAGS
;
10329 if (copy_to_user(params
, p
, sizeof(*p
))) {
10334 file
= io_uring_get_file(ctx
);
10335 if (IS_ERR(file
)) {
10336 ret
= PTR_ERR(file
);
10341 * Install ring fd as the very last thing, so we don't risk someone
10342 * having closed it before we finish setup
10344 ret
= io_uring_install_fd(ctx
, file
);
10346 /* fput will clean it up */
10351 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
10354 io_ring_ctx_wait_and_kill(ctx
);
10359 * Sets up an aio uring context, and returns the fd. Applications asks for a
10360 * ring size, we return the actual sq/cq ring sizes (among other things) in the
10361 * params structure passed in.
10363 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
10365 struct io_uring_params p
;
10368 if (copy_from_user(&p
, params
, sizeof(p
)))
10370 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
10375 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
10376 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
10377 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
10378 IORING_SETUP_R_DISABLED
))
10381 return io_uring_create(entries
, &p
, params
);
10384 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
10385 struct io_uring_params __user
*, params
)
10387 return io_uring_setup(entries
, params
);
10390 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
10392 struct io_uring_probe
*p
;
10396 size
= struct_size(p
, ops
, nr_args
);
10397 if (size
== SIZE_MAX
)
10399 p
= kzalloc(size
, GFP_KERNEL
);
10404 if (copy_from_user(p
, arg
, size
))
10407 if (memchr_inv(p
, 0, size
))
10410 p
->last_op
= IORING_OP_LAST
- 1;
10411 if (nr_args
> IORING_OP_LAST
)
10412 nr_args
= IORING_OP_LAST
;
10414 for (i
= 0; i
< nr_args
; i
++) {
10416 if (!io_op_defs
[i
].not_supported
)
10417 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
10422 if (copy_to_user(arg
, p
, size
))
10429 static int io_register_personality(struct io_ring_ctx
*ctx
)
10431 const struct cred
*creds
;
10435 creds
= get_current_cred();
10437 ret
= xa_alloc_cyclic(&ctx
->personalities
, &id
, (void *)creds
,
10438 XA_LIMIT(0, USHRT_MAX
), &ctx
->pers_next
, GFP_KERNEL
);
10446 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
10447 unsigned int nr_args
)
10449 struct io_uring_restriction
*res
;
10453 /* Restrictions allowed only if rings started disabled */
10454 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
10457 /* We allow only a single restrictions registration */
10458 if (ctx
->restrictions
.registered
)
10461 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
10464 size
= array_size(nr_args
, sizeof(*res
));
10465 if (size
== SIZE_MAX
)
10468 res
= memdup_user(arg
, size
);
10470 return PTR_ERR(res
);
10474 for (i
= 0; i
< nr_args
; i
++) {
10475 switch (res
[i
].opcode
) {
10476 case IORING_RESTRICTION_REGISTER_OP
:
10477 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
10482 __set_bit(res
[i
].register_op
,
10483 ctx
->restrictions
.register_op
);
10485 case IORING_RESTRICTION_SQE_OP
:
10486 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
10491 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
10493 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
10494 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
10496 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
10497 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
10506 /* Reset all restrictions if an error happened */
10508 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
10510 ctx
->restrictions
.registered
= true;
10516 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
10518 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
10521 if (ctx
->restrictions
.registered
)
10522 ctx
->restricted
= 1;
10524 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
10525 if (ctx
->sq_data
&& wq_has_sleeper(&ctx
->sq_data
->wait
))
10526 wake_up(&ctx
->sq_data
->wait
);
10530 static int __io_register_rsrc_update(struct io_ring_ctx
*ctx
, unsigned type
,
10531 struct io_uring_rsrc_update2
*up
,
10539 if (check_add_overflow(up
->offset
, nr_args
, &tmp
))
10541 err
= io_rsrc_node_switch_start(ctx
);
10546 case IORING_RSRC_FILE
:
10547 return __io_sqe_files_update(ctx
, up
, nr_args
);
10548 case IORING_RSRC_BUFFER
:
10549 return __io_sqe_buffers_update(ctx
, up
, nr_args
);
10554 static int io_register_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
10557 struct io_uring_rsrc_update2 up
;
10561 memset(&up
, 0, sizeof(up
));
10562 if (copy_from_user(&up
, arg
, sizeof(struct io_uring_rsrc_update
)))
10564 return __io_register_rsrc_update(ctx
, IORING_RSRC_FILE
, &up
, nr_args
);
10567 static int io_register_rsrc_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
10568 unsigned size
, unsigned type
)
10570 struct io_uring_rsrc_update2 up
;
10572 if (size
!= sizeof(up
))
10574 if (copy_from_user(&up
, arg
, sizeof(up
)))
10576 if (!up
.nr
|| up
.resv
)
10578 return __io_register_rsrc_update(ctx
, type
, &up
, up
.nr
);
10581 static int io_register_rsrc(struct io_ring_ctx
*ctx
, void __user
*arg
,
10582 unsigned int size
, unsigned int type
)
10584 struct io_uring_rsrc_register rr
;
10586 /* keep it extendible */
10587 if (size
!= sizeof(rr
))
10590 memset(&rr
, 0, sizeof(rr
));
10591 if (copy_from_user(&rr
, arg
, size
))
10593 if (!rr
.nr
|| rr
.resv
|| rr
.resv2
)
10597 case IORING_RSRC_FILE
:
10598 return io_sqe_files_register(ctx
, u64_to_user_ptr(rr
.data
),
10599 rr
.nr
, u64_to_user_ptr(rr
.tags
));
10600 case IORING_RSRC_BUFFER
:
10601 return io_sqe_buffers_register(ctx
, u64_to_user_ptr(rr
.data
),
10602 rr
.nr
, u64_to_user_ptr(rr
.tags
));
10607 static int io_register_iowq_aff(struct io_ring_ctx
*ctx
, void __user
*arg
,
10610 struct io_uring_task
*tctx
= current
->io_uring
;
10611 cpumask_var_t new_mask
;
10614 if (!tctx
|| !tctx
->io_wq
)
10617 if (!alloc_cpumask_var(&new_mask
, GFP_KERNEL
))
10620 cpumask_clear(new_mask
);
10621 if (len
> cpumask_size())
10622 len
= cpumask_size();
10624 if (copy_from_user(new_mask
, arg
, len
)) {
10625 free_cpumask_var(new_mask
);
10629 ret
= io_wq_cpu_affinity(tctx
->io_wq
, new_mask
);
10630 free_cpumask_var(new_mask
);
10634 static int io_unregister_iowq_aff(struct io_ring_ctx
*ctx
)
10636 struct io_uring_task
*tctx
= current
->io_uring
;
10638 if (!tctx
|| !tctx
->io_wq
)
10641 return io_wq_cpu_affinity(tctx
->io_wq
, NULL
);
10644 static int io_register_iowq_max_workers(struct io_ring_ctx
*ctx
,
10647 struct io_uring_task
*tctx
= NULL
;
10648 struct io_sq_data
*sqd
= NULL
;
10649 __u32 new_count
[2];
10652 if (copy_from_user(new_count
, arg
, sizeof(new_count
)))
10654 for (i
= 0; i
< ARRAY_SIZE(new_count
); i
++)
10655 if (new_count
[i
] > INT_MAX
)
10658 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
10659 sqd
= ctx
->sq_data
;
10662 * Observe the correct sqd->lock -> ctx->uring_lock
10663 * ordering. Fine to drop uring_lock here, we hold
10664 * a ref to the ctx.
10666 refcount_inc(&sqd
->refs
);
10667 mutex_unlock(&ctx
->uring_lock
);
10668 mutex_lock(&sqd
->lock
);
10669 mutex_lock(&ctx
->uring_lock
);
10671 tctx
= sqd
->thread
->io_uring
;
10674 tctx
= current
->io_uring
;
10678 if (!tctx
|| !tctx
->io_wq
)
10681 ret
= io_wq_max_workers(tctx
->io_wq
, new_count
);
10686 mutex_unlock(&sqd
->lock
);
10687 io_put_sq_data(sqd
);
10690 if (copy_to_user(arg
, new_count
, sizeof(new_count
)))
10696 mutex_unlock(&sqd
->lock
);
10697 io_put_sq_data(sqd
);
10702 static bool io_register_op_must_quiesce(int op
)
10705 case IORING_REGISTER_BUFFERS
:
10706 case IORING_UNREGISTER_BUFFERS
:
10707 case IORING_REGISTER_FILES
:
10708 case IORING_UNREGISTER_FILES
:
10709 case IORING_REGISTER_FILES_UPDATE
:
10710 case IORING_REGISTER_PROBE
:
10711 case IORING_REGISTER_PERSONALITY
:
10712 case IORING_UNREGISTER_PERSONALITY
:
10713 case IORING_REGISTER_FILES2
:
10714 case IORING_REGISTER_FILES_UPDATE2
:
10715 case IORING_REGISTER_BUFFERS2
:
10716 case IORING_REGISTER_BUFFERS_UPDATE
:
10717 case IORING_REGISTER_IOWQ_AFF
:
10718 case IORING_UNREGISTER_IOWQ_AFF
:
10719 case IORING_REGISTER_IOWQ_MAX_WORKERS
:
10726 static int io_ctx_quiesce(struct io_ring_ctx
*ctx
)
10730 percpu_ref_kill(&ctx
->refs
);
10733 * Drop uring mutex before waiting for references to exit. If another
10734 * thread is currently inside io_uring_enter() it might need to grab the
10735 * uring_lock to make progress. If we hold it here across the drain
10736 * wait, then we can deadlock. It's safe to drop the mutex here, since
10737 * no new references will come in after we've killed the percpu ref.
10739 mutex_unlock(&ctx
->uring_lock
);
10741 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
10744 ret
= io_run_task_work_sig();
10745 } while (ret
>= 0);
10746 mutex_lock(&ctx
->uring_lock
);
10749 io_refs_resurrect(&ctx
->refs
, &ctx
->ref_comp
);
10753 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
10754 void __user
*arg
, unsigned nr_args
)
10755 __releases(ctx
->uring_lock
)
10756 __acquires(ctx
->uring_lock
)
10761 * We're inside the ring mutex, if the ref is already dying, then
10762 * someone else killed the ctx or is already going through
10763 * io_uring_register().
10765 if (percpu_ref_is_dying(&ctx
->refs
))
10768 if (ctx
->restricted
) {
10769 if (opcode
>= IORING_REGISTER_LAST
)
10771 opcode
= array_index_nospec(opcode
, IORING_REGISTER_LAST
);
10772 if (!test_bit(opcode
, ctx
->restrictions
.register_op
))
10776 if (io_register_op_must_quiesce(opcode
)) {
10777 ret
= io_ctx_quiesce(ctx
);
10783 case IORING_REGISTER_BUFFERS
:
10784 ret
= io_sqe_buffers_register(ctx
, arg
, nr_args
, NULL
);
10786 case IORING_UNREGISTER_BUFFERS
:
10788 if (arg
|| nr_args
)
10790 ret
= io_sqe_buffers_unregister(ctx
);
10792 case IORING_REGISTER_FILES
:
10793 ret
= io_sqe_files_register(ctx
, arg
, nr_args
, NULL
);
10795 case IORING_UNREGISTER_FILES
:
10797 if (arg
|| nr_args
)
10799 ret
= io_sqe_files_unregister(ctx
);
10801 case IORING_REGISTER_FILES_UPDATE
:
10802 ret
= io_register_files_update(ctx
, arg
, nr_args
);
10804 case IORING_REGISTER_EVENTFD
:
10805 case IORING_REGISTER_EVENTFD_ASYNC
:
10809 ret
= io_eventfd_register(ctx
, arg
);
10812 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
10813 ctx
->eventfd_async
= 1;
10815 ctx
->eventfd_async
= 0;
10817 case IORING_UNREGISTER_EVENTFD
:
10819 if (arg
|| nr_args
)
10821 ret
= io_eventfd_unregister(ctx
);
10823 case IORING_REGISTER_PROBE
:
10825 if (!arg
|| nr_args
> 256)
10827 ret
= io_probe(ctx
, arg
, nr_args
);
10829 case IORING_REGISTER_PERSONALITY
:
10831 if (arg
|| nr_args
)
10833 ret
= io_register_personality(ctx
);
10835 case IORING_UNREGISTER_PERSONALITY
:
10839 ret
= io_unregister_personality(ctx
, nr_args
);
10841 case IORING_REGISTER_ENABLE_RINGS
:
10843 if (arg
|| nr_args
)
10845 ret
= io_register_enable_rings(ctx
);
10847 case IORING_REGISTER_RESTRICTIONS
:
10848 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
10850 case IORING_REGISTER_FILES2
:
10851 ret
= io_register_rsrc(ctx
, arg
, nr_args
, IORING_RSRC_FILE
);
10853 case IORING_REGISTER_FILES_UPDATE2
:
10854 ret
= io_register_rsrc_update(ctx
, arg
, nr_args
,
10857 case IORING_REGISTER_BUFFERS2
:
10858 ret
= io_register_rsrc(ctx
, arg
, nr_args
, IORING_RSRC_BUFFER
);
10860 case IORING_REGISTER_BUFFERS_UPDATE
:
10861 ret
= io_register_rsrc_update(ctx
, arg
, nr_args
,
10862 IORING_RSRC_BUFFER
);
10864 case IORING_REGISTER_IOWQ_AFF
:
10866 if (!arg
|| !nr_args
)
10868 ret
= io_register_iowq_aff(ctx
, arg
, nr_args
);
10870 case IORING_UNREGISTER_IOWQ_AFF
:
10872 if (arg
|| nr_args
)
10874 ret
= io_unregister_iowq_aff(ctx
);
10876 case IORING_REGISTER_IOWQ_MAX_WORKERS
:
10878 if (!arg
|| nr_args
!= 2)
10880 ret
= io_register_iowq_max_workers(ctx
, arg
);
10887 if (io_register_op_must_quiesce(opcode
)) {
10888 /* bring the ctx back to life */
10889 percpu_ref_reinit(&ctx
->refs
);
10890 reinit_completion(&ctx
->ref_comp
);
10895 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
10896 void __user
*, arg
, unsigned int, nr_args
)
10898 struct io_ring_ctx
*ctx
;
10907 if (f
.file
->f_op
!= &io_uring_fops
)
10910 ctx
= f
.file
->private_data
;
10912 io_run_task_work();
10914 mutex_lock(&ctx
->uring_lock
);
10915 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
10916 mutex_unlock(&ctx
->uring_lock
);
10917 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
10918 ctx
->cq_ev_fd
!= NULL
, ret
);
10924 static int __init
io_uring_init(void)
10926 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10927 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10928 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10931 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10932 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10933 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
10934 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
10935 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
10936 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
10937 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
10938 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
10939 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
10940 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
10941 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
10942 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
10943 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
10944 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
10945 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
10946 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
10947 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
10948 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
10949 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
10950 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
10951 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
10952 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
10953 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
10954 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
10955 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
10956 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
10957 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
10958 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
10959 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
10960 BUILD_BUG_SQE_ELEM(40, __u16
, buf_group
);
10961 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
10962 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
10963 BUILD_BUG_SQE_ELEM(44, __u32
, file_index
);
10965 BUILD_BUG_ON(sizeof(struct io_uring_files_update
) !=
10966 sizeof(struct io_uring_rsrc_update
));
10967 BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update
) >
10968 sizeof(struct io_uring_rsrc_update2
));
10970 /* ->buf_index is u16 */
10971 BUILD_BUG_ON(IORING_MAX_REG_BUFFERS
>= (1u << 16));
10973 /* should fit into one byte */
10974 BUILD_BUG_ON(SQE_VALID_FLAGS
>= (1 << 8));
10976 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
10977 BUILD_BUG_ON(__REQ_F_LAST_BIT
> 8 * sizeof(int));
10979 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
|
10983 __initcall(io_uring_init
);