1 // SPDX-License-Identifier: GPL-2.0
3 * Shared application/kernel submission and completion ring pairs, for
4 * supporting fast/efficient IO.
6 * A note on the read/write ordering memory barriers that are matched between
7 * the application and kernel side.
9 * After the application reads the CQ ring tail, it must use an
10 * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
11 * before writing the tail (using smp_load_acquire to read the tail will
12 * do). It also needs a smp_mb() before updating CQ head (ordering the
13 * entry load(s) with the head store), pairing with an implicit barrier
14 * through a control-dependency in io_get_cqring (smp_store_release to
15 * store head will do). Failure to do so could lead to reading invalid
18 * Likewise, the application must use an appropriate smp_wmb() before
19 * writing the SQ tail (ordering SQ entry stores with the tail store),
20 * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
21 * to store the tail will do). And it needs a barrier ordering the SQ
22 * head load before writing new SQ entries (smp_load_acquire to read
25 * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
26 * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
27 * updating the SQ tail; a full memory barrier smp_mb() is needed
30 * Also see the examples in the liburing library:
32 * git://git.kernel.dk/liburing
34 * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
35 * from data shared between the kernel and application. This is done both
36 * for ordering purposes, but also to ensure that once a value is loaded from
37 * data that the application could potentially modify, it remains stable.
39 * Copyright (C) 2018-2019 Jens Axboe
40 * Copyright (c) 2018-2019 Christoph Hellwig
42 #include <linux/kernel.h>
43 #include <linux/init.h>
44 #include <linux/errno.h>
45 #include <linux/syscalls.h>
46 #include <linux/compat.h>
47 #include <net/compat.h>
48 #include <linux/refcount.h>
49 #include <linux/uio.h>
50 #include <linux/bits.h>
52 #include <linux/sched/signal.h>
54 #include <linux/file.h>
55 #include <linux/fdtable.h>
57 #include <linux/mman.h>
58 #include <linux/percpu.h>
59 #include <linux/slab.h>
60 #include <linux/kthread.h>
61 #include <linux/blkdev.h>
62 #include <linux/bvec.h>
63 #include <linux/net.h>
65 #include <net/af_unix.h>
67 #include <linux/anon_inodes.h>
68 #include <linux/sched/mm.h>
69 #include <linux/uaccess.h>
70 #include <linux/nospec.h>
71 #include <linux/sizes.h>
72 #include <linux/hugetlb.h>
73 #include <linux/highmem.h>
74 #include <linux/namei.h>
75 #include <linux/fsnotify.h>
76 #include <linux/fadvise.h>
77 #include <linux/eventpoll.h>
78 #include <linux/fs_struct.h>
79 #include <linux/splice.h>
80 #include <linux/task_work.h>
81 #include <linux/pagemap.h>
82 #include <linux/io_uring.h>
83 #include <linux/blk-cgroup.h>
84 #include <linux/audit.h>
86 #define CREATE_TRACE_POINTS
87 #include <trace/events/io_uring.h>
89 #include <uapi/linux/io_uring.h>
94 #define IORING_MAX_ENTRIES 32768
95 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
98 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
100 #define IORING_FILE_TABLE_SHIFT 9
101 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
102 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
103 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
104 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
105 IORING_REGISTER_LAST + IORING_OP_LAST)
108 u32 head ____cacheline_aligned_in_smp
;
109 u32 tail ____cacheline_aligned_in_smp
;
113 * This data is shared with the application through the mmap at offsets
114 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
116 * The offsets to the member fields are published through struct
117 * io_sqring_offsets when calling io_uring_setup.
121 * Head and tail offsets into the ring; the offsets need to be
122 * masked to get valid indices.
124 * The kernel controls head of the sq ring and the tail of the cq ring,
125 * and the application controls tail of the sq ring and the head of the
128 struct io_uring sq
, cq
;
130 * Bitmasks to apply to head and tail offsets (constant, equals
133 u32 sq_ring_mask
, cq_ring_mask
;
134 /* Ring sizes (constant, power of 2) */
135 u32 sq_ring_entries
, cq_ring_entries
;
137 * Number of invalid entries dropped by the kernel due to
138 * invalid index stored in array
140 * Written by the kernel, shouldn't be modified by the
141 * application (i.e. get number of "new events" by comparing to
144 * After a new SQ head value was read by the application this
145 * counter includes all submissions that were dropped reaching
146 * the new SQ head (and possibly more).
152 * Written by the kernel, shouldn't be modified by the
155 * The application needs a full memory barrier before checking
156 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
162 * Written by the application, shouldn't be modified by the
167 * Number of completion events lost because the queue was full;
168 * this should be avoided by the application by making sure
169 * there are not more requests pending than there is space in
170 * the completion queue.
172 * Written by the kernel, shouldn't be modified by the
173 * application (i.e. get number of "new events" by comparing to
176 * As completion events come in out of order this counter is not
177 * ordered with any other data.
181 * Ring buffer of completion events.
183 * The kernel writes completion events fresh every time they are
184 * produced, so the application is allowed to modify pending
187 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
190 struct io_mapped_ubuf
{
193 struct bio_vec
*bvec
;
194 unsigned int nr_bvecs
;
195 unsigned long acct_pages
;
198 struct fixed_file_table
{
202 struct fixed_file_ref_node
{
203 struct percpu_ref refs
;
204 struct list_head node
;
205 struct list_head file_list
;
206 struct fixed_file_data
*file_data
;
207 struct llist_node llist
;
210 struct fixed_file_data
{
211 struct fixed_file_table
*table
;
212 struct io_ring_ctx
*ctx
;
214 struct fixed_file_ref_node
*node
;
215 struct percpu_ref refs
;
216 struct completion done
;
217 struct list_head ref_list
;
222 struct list_head list
;
228 struct io_restriction
{
229 DECLARE_BITMAP(register_op
, IORING_REGISTER_LAST
);
230 DECLARE_BITMAP(sqe_op
, IORING_OP_LAST
);
231 u8 sqe_flags_allowed
;
232 u8 sqe_flags_required
;
240 /* ctx's that are using this sqd */
241 struct list_head ctx_list
;
242 struct list_head ctx_new_list
;
243 struct mutex ctx_lock
;
245 struct task_struct
*thread
;
246 struct wait_queue_head wait
;
251 struct percpu_ref refs
;
252 } ____cacheline_aligned_in_smp
;
256 unsigned int compat
: 1;
257 unsigned int limit_mem
: 1;
258 unsigned int cq_overflow_flushed
: 1;
259 unsigned int drain_next
: 1;
260 unsigned int eventfd_async
: 1;
261 unsigned int restricted
: 1;
264 * Ring buffer of indices into array of io_uring_sqe, which is
265 * mmapped by the application using the IORING_OFF_SQES offset.
267 * This indirection could e.g. be used to assign fixed
268 * io_uring_sqe entries to operations and only submit them to
269 * the queue when needed.
271 * The kernel modifies neither the indices array nor the entries
275 unsigned cached_sq_head
;
278 unsigned sq_thread_idle
;
279 unsigned cached_sq_dropped
;
280 atomic_t cached_cq_overflow
;
281 unsigned long sq_check_overflow
;
283 struct list_head defer_list
;
284 struct list_head timeout_list
;
285 struct list_head cq_overflow_list
;
287 wait_queue_head_t inflight_wait
;
288 struct io_uring_sqe
*sq_sqes
;
289 } ____cacheline_aligned_in_smp
;
291 struct io_rings
*rings
;
297 * For SQPOLL usage - we hold a reference to the parent task, so we
298 * have access to the ->files
300 struct task_struct
*sqo_task
;
302 /* Only used for accounting purposes */
303 struct mm_struct
*mm_account
;
305 #ifdef CONFIG_BLK_CGROUP
306 struct cgroup_subsys_state
*sqo_blkcg_css
;
309 struct io_sq_data
*sq_data
; /* if using sq thread polling */
311 struct wait_queue_head sqo_sq_wait
;
312 struct wait_queue_entry sqo_wait_entry
;
313 struct list_head sqd_list
;
316 * If used, fixed file set. Writers must ensure that ->refs is dead,
317 * readers must ensure that ->refs is alive as long as the file* is
318 * used. Only updated through io_uring_register(2).
320 struct fixed_file_data
*file_data
;
321 unsigned nr_user_files
;
323 /* if used, fixed mapped user buffers */
324 unsigned nr_user_bufs
;
325 struct io_mapped_ubuf
*user_bufs
;
327 struct user_struct
*user
;
329 const struct cred
*creds
;
333 unsigned int sessionid
;
336 struct completion ref_comp
;
337 struct completion sq_thread_comp
;
339 /* if all else fails... */
340 struct io_kiocb
*fallback_req
;
342 #if defined(CONFIG_UNIX)
343 struct socket
*ring_sock
;
346 struct idr io_buffer_idr
;
348 struct idr personality_idr
;
351 unsigned cached_cq_tail
;
354 atomic_t cq_timeouts
;
355 unsigned long cq_check_overflow
;
356 struct wait_queue_head cq_wait
;
357 struct fasync_struct
*cq_fasync
;
358 struct eventfd_ctx
*cq_ev_fd
;
359 } ____cacheline_aligned_in_smp
;
362 struct mutex uring_lock
;
363 wait_queue_head_t wait
;
364 } ____cacheline_aligned_in_smp
;
367 spinlock_t completion_lock
;
370 * ->iopoll_list is protected by the ctx->uring_lock for
371 * io_uring instances that don't use IORING_SETUP_SQPOLL.
372 * For SQPOLL, only the single threaded io_sq_thread() will
373 * manipulate the list, hence no extra locking is needed there.
375 struct list_head iopoll_list
;
376 struct hlist_head
*cancel_hash
;
377 unsigned cancel_hash_bits
;
378 bool poll_multi_file
;
380 spinlock_t inflight_lock
;
381 struct list_head inflight_list
;
382 } ____cacheline_aligned_in_smp
;
384 struct delayed_work file_put_work
;
385 struct llist_head file_put_llist
;
387 struct work_struct exit_work
;
388 struct io_restriction restrictions
;
392 * First field must be the file pointer in all the
393 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
395 struct io_poll_iocb
{
398 struct wait_queue_head
*head
;
404 struct wait_queue_entry wait
;
409 struct file
*put_file
;
413 struct io_timeout_data
{
414 struct io_kiocb
*req
;
415 struct hrtimer timer
;
416 struct timespec64 ts
;
417 enum hrtimer_mode mode
;
422 struct sockaddr __user
*addr
;
423 int __user
*addr_len
;
425 unsigned long nofile
;
445 struct list_head list
;
448 struct io_timeout_rem
{
454 /* NOTE: kiocb has the file as the first member, so don't do it here */
462 struct sockaddr __user
*addr
;
469 struct user_msghdr __user
*umsg
;
475 struct io_buffer
*kbuf
;
481 struct filename
*filename
;
483 unsigned long nofile
;
486 struct io_files_update
{
512 struct epoll_event event
;
516 struct file
*file_out
;
517 struct file
*file_in
;
524 struct io_provide_buf
{
538 const char __user
*filename
;
539 struct statx __user
*buffer
;
542 struct io_completion
{
544 struct list_head list
;
548 struct io_async_connect
{
549 struct sockaddr_storage address
;
552 struct io_async_msghdr
{
553 struct iovec fast_iov
[UIO_FASTIOV
];
555 struct sockaddr __user
*uaddr
;
557 struct sockaddr_storage addr
;
561 struct iovec fast_iov
[UIO_FASTIOV
];
562 const struct iovec
*free_iovec
;
563 struct iov_iter iter
;
565 struct wait_page_queue wpq
;
569 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
570 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
571 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
572 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
573 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
574 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
581 REQ_F_LINK_TIMEOUT_BIT
,
583 REQ_F_NEED_CLEANUP_BIT
,
585 REQ_F_BUFFER_SELECTED_BIT
,
586 REQ_F_NO_FILE_TABLE_BIT
,
587 REQ_F_WORK_INITIALIZED_BIT
,
589 /* not a real bit, just to check we're not overflowing the space */
595 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
596 /* drain existing IO first */
597 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
599 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
600 /* doesn't sever on completion < 0 */
601 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
603 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
604 /* IOSQE_BUFFER_SELECT */
605 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
608 REQ_F_LINK_HEAD
= BIT(REQ_F_LINK_HEAD_BIT
),
609 /* fail rest of links */
610 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
611 /* on inflight list */
612 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
613 /* read/write uses file position */
614 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
615 /* must not punt to workers */
616 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
617 /* has linked timeout */
618 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
620 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
622 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
623 /* already went through poll handler */
624 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
625 /* buffer already selected */
626 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
627 /* doesn't need file table for this request */
628 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
629 /* io_wq_work is initialized */
630 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
634 struct io_poll_iocb poll
;
635 struct io_poll_iocb
*double_poll
;
639 * NOTE! Each of the iocb union members has the file pointer
640 * as the first entry in their struct definition. So you can
641 * access the file pointer through any of the sub-structs,
642 * or directly as just 'ki_filp' in this struct.
648 struct io_poll_iocb poll
;
649 struct io_accept accept
;
651 struct io_cancel cancel
;
652 struct io_timeout timeout
;
653 struct io_timeout_rem timeout_rem
;
654 struct io_connect connect
;
655 struct io_sr_msg sr_msg
;
657 struct io_close close
;
658 struct io_files_update files_update
;
659 struct io_fadvise fadvise
;
660 struct io_madvise madvise
;
661 struct io_epoll epoll
;
662 struct io_splice splice
;
663 struct io_provide_buf pbuf
;
664 struct io_statx statx
;
665 /* use only after cleaning per-op data, see io_clean_op() */
666 struct io_completion
compl;
669 /* opcode allocated if it needs to store data for async defer */
672 /* polled IO has completed */
678 struct io_ring_ctx
*ctx
;
681 struct task_struct
*task
;
684 struct list_head link_list
;
687 * 1. used with ctx->iopoll_list with reads/writes
688 * 2. to track reqs with ->files (see io_op_def::file_table)
690 struct list_head inflight_entry
;
692 struct percpu_ref
*fixed_file_refs
;
693 struct callback_head task_work
;
694 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
695 struct hlist_node hash_node
;
696 struct async_poll
*apoll
;
697 struct io_wq_work work
;
700 struct io_defer_entry
{
701 struct list_head list
;
702 struct io_kiocb
*req
;
706 #define IO_IOPOLL_BATCH 8
708 struct io_comp_state
{
710 struct list_head list
;
711 struct io_ring_ctx
*ctx
;
714 struct io_submit_state
{
715 struct blk_plug plug
;
718 * io_kiocb alloc cache
720 void *reqs
[IO_IOPOLL_BATCH
];
721 unsigned int free_reqs
;
724 * Batch completion logic
726 struct io_comp_state comp
;
729 * File reference cache
733 unsigned int has_refs
;
734 unsigned int ios_left
;
738 /* needs req->file assigned */
739 unsigned needs_file
: 1;
740 /* don't fail if file grab fails */
741 unsigned needs_file_no_error
: 1;
742 /* hash wq insertion if file is a regular file */
743 unsigned hash_reg_file
: 1;
744 /* unbound wq insertion if file is a non-regular file */
745 unsigned unbound_nonreg_file
: 1;
746 /* opcode is not supported by this kernel */
747 unsigned not_supported
: 1;
748 /* set if opcode supports polled "wait" */
750 unsigned pollout
: 1;
751 /* op supports buffer selection */
752 unsigned buffer_select
: 1;
753 /* needs rlimit(RLIMIT_FSIZE) assigned */
754 unsigned needs_fsize
: 1;
755 /* must always have async data allocated */
756 unsigned needs_async_data
: 1;
757 /* size of async data needed, if any */
758 unsigned short async_size
;
762 static const struct io_op_def io_op_defs
[] = {
763 [IORING_OP_NOP
] = {},
764 [IORING_OP_READV
] = {
766 .unbound_nonreg_file
= 1,
769 .needs_async_data
= 1,
770 .async_size
= sizeof(struct io_async_rw
),
771 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
773 [IORING_OP_WRITEV
] = {
776 .unbound_nonreg_file
= 1,
779 .needs_async_data
= 1,
780 .async_size
= sizeof(struct io_async_rw
),
781 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
783 [IORING_OP_FSYNC
] = {
785 .work_flags
= IO_WQ_WORK_BLKCG
,
787 [IORING_OP_READ_FIXED
] = {
789 .unbound_nonreg_file
= 1,
791 .async_size
= sizeof(struct io_async_rw
),
792 .work_flags
= IO_WQ_WORK_BLKCG
,
794 [IORING_OP_WRITE_FIXED
] = {
797 .unbound_nonreg_file
= 1,
800 .async_size
= sizeof(struct io_async_rw
),
801 .work_flags
= IO_WQ_WORK_BLKCG
,
803 [IORING_OP_POLL_ADD
] = {
805 .unbound_nonreg_file
= 1,
807 [IORING_OP_POLL_REMOVE
] = {},
808 [IORING_OP_SYNC_FILE_RANGE
] = {
810 .work_flags
= IO_WQ_WORK_BLKCG
,
812 [IORING_OP_SENDMSG
] = {
814 .unbound_nonreg_file
= 1,
816 .needs_async_data
= 1,
817 .async_size
= sizeof(struct io_async_msghdr
),
818 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
821 [IORING_OP_RECVMSG
] = {
823 .unbound_nonreg_file
= 1,
826 .needs_async_data
= 1,
827 .async_size
= sizeof(struct io_async_msghdr
),
828 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
|
831 [IORING_OP_TIMEOUT
] = {
832 .needs_async_data
= 1,
833 .async_size
= sizeof(struct io_timeout_data
),
834 .work_flags
= IO_WQ_WORK_MM
,
836 [IORING_OP_TIMEOUT_REMOVE
] = {},
837 [IORING_OP_ACCEPT
] = {
839 .unbound_nonreg_file
= 1,
841 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_FILES
,
843 [IORING_OP_ASYNC_CANCEL
] = {},
844 [IORING_OP_LINK_TIMEOUT
] = {
845 .needs_async_data
= 1,
846 .async_size
= sizeof(struct io_timeout_data
),
847 .work_flags
= IO_WQ_WORK_MM
,
849 [IORING_OP_CONNECT
] = {
851 .unbound_nonreg_file
= 1,
853 .needs_async_data
= 1,
854 .async_size
= sizeof(struct io_async_connect
),
855 .work_flags
= IO_WQ_WORK_MM
,
857 [IORING_OP_FALLOCATE
] = {
860 .work_flags
= IO_WQ_WORK_BLKCG
,
862 [IORING_OP_OPENAT
] = {
863 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
|
866 [IORING_OP_CLOSE
] = {
868 .needs_file_no_error
= 1,
869 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_BLKCG
,
871 [IORING_OP_FILES_UPDATE
] = {
872 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
,
874 [IORING_OP_STATX
] = {
875 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_MM
|
876 IO_WQ_WORK_FS
| IO_WQ_WORK_BLKCG
,
880 .unbound_nonreg_file
= 1,
883 .async_size
= sizeof(struct io_async_rw
),
884 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
886 [IORING_OP_WRITE
] = {
888 .unbound_nonreg_file
= 1,
891 .async_size
= sizeof(struct io_async_rw
),
892 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
894 [IORING_OP_FADVISE
] = {
896 .work_flags
= IO_WQ_WORK_BLKCG
,
898 [IORING_OP_MADVISE
] = {
899 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
903 .unbound_nonreg_file
= 1,
905 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
909 .unbound_nonreg_file
= 1,
912 .work_flags
= IO_WQ_WORK_MM
| IO_WQ_WORK_BLKCG
,
914 [IORING_OP_OPENAT2
] = {
915 .work_flags
= IO_WQ_WORK_FILES
| IO_WQ_WORK_FS
|
918 [IORING_OP_EPOLL_CTL
] = {
919 .unbound_nonreg_file
= 1,
920 .work_flags
= IO_WQ_WORK_FILES
,
922 [IORING_OP_SPLICE
] = {
925 .unbound_nonreg_file
= 1,
926 .work_flags
= IO_WQ_WORK_BLKCG
,
928 [IORING_OP_PROVIDE_BUFFERS
] = {},
929 [IORING_OP_REMOVE_BUFFERS
] = {},
933 .unbound_nonreg_file
= 1,
937 enum io_mem_account
{
942 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
943 struct io_comp_state
*cs
);
944 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
945 static void io_put_req(struct io_kiocb
*req
);
946 static void io_put_req_deferred(struct io_kiocb
*req
, int nr
);
947 static void io_double_put_req(struct io_kiocb
*req
);
948 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
949 static void __io_queue_linked_timeout(struct io_kiocb
*req
);
950 static void io_queue_linked_timeout(struct io_kiocb
*req
);
951 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
952 struct io_uring_files_update
*ip
,
954 static void __io_clean_op(struct io_kiocb
*req
);
955 static struct file
*io_file_get(struct io_submit_state
*state
,
956 struct io_kiocb
*req
, int fd
, bool fixed
);
957 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
);
958 static void io_file_put_work(struct work_struct
*work
);
960 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
961 struct iovec
**iovec
, struct iov_iter
*iter
,
963 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
964 const struct iovec
*fast_iov
,
965 struct iov_iter
*iter
, bool force
);
967 static struct kmem_cache
*req_cachep
;
969 static const struct file_operations io_uring_fops
;
971 struct sock
*io_uring_get_socket(struct file
*file
)
973 #if defined(CONFIG_UNIX)
974 if (file
->f_op
== &io_uring_fops
) {
975 struct io_ring_ctx
*ctx
= file
->private_data
;
977 return ctx
->ring_sock
->sk
;
982 EXPORT_SYMBOL(io_uring_get_socket
);
984 static inline void io_clean_op(struct io_kiocb
*req
)
986 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
|
991 static void io_sq_thread_drop_mm(void)
993 struct mm_struct
*mm
= current
->mm
;
996 kthread_unuse_mm(mm
);
1001 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
1004 if (unlikely(!(ctx
->flags
& IORING_SETUP_SQPOLL
) ||
1005 !ctx
->sqo_task
->mm
||
1006 !mmget_not_zero(ctx
->sqo_task
->mm
)))
1008 kthread_use_mm(ctx
->sqo_task
->mm
);
1014 static int io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
,
1015 struct io_kiocb
*req
)
1017 if (!(io_op_defs
[req
->opcode
].work_flags
& IO_WQ_WORK_MM
))
1019 return __io_sq_thread_acquire_mm(ctx
);
1022 static void io_sq_thread_associate_blkcg(struct io_ring_ctx
*ctx
,
1023 struct cgroup_subsys_state
**cur_css
)
1026 #ifdef CONFIG_BLK_CGROUP
1027 /* puts the old one when swapping */
1028 if (*cur_css
!= ctx
->sqo_blkcg_css
) {
1029 kthread_associate_blkcg(ctx
->sqo_blkcg_css
);
1030 *cur_css
= ctx
->sqo_blkcg_css
;
1035 static void io_sq_thread_unassociate_blkcg(void)
1037 #ifdef CONFIG_BLK_CGROUP
1038 kthread_associate_blkcg(NULL
);
1042 static inline void req_set_fail_links(struct io_kiocb
*req
)
1044 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1045 req
->flags
|= REQ_F_FAIL_LINK
;
1049 * None of these are dereferenced, they are simply used to check if any of
1050 * them have changed. If we're under current and check they are still the
1051 * same, we're fine to grab references to them for actual out-of-line use.
1053 static void io_init_identity(struct io_identity
*id
)
1055 id
->files
= current
->files
;
1056 id
->mm
= current
->mm
;
1057 #ifdef CONFIG_BLK_CGROUP
1059 id
->blkcg_css
= blkcg_css();
1062 id
->creds
= current_cred();
1063 id
->nsproxy
= current
->nsproxy
;
1064 id
->fs
= current
->fs
;
1065 id
->fsize
= rlimit(RLIMIT_FSIZE
);
1067 id
->loginuid
= current
->loginuid
;
1068 id
->sessionid
= current
->sessionid
;
1070 refcount_set(&id
->count
, 1);
1074 * Note: must call io_req_init_async() for the first time you
1075 * touch any members of io_wq_work.
1077 static inline void io_req_init_async(struct io_kiocb
*req
)
1079 struct io_uring_task
*tctx
= current
->io_uring
;
1081 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1084 memset(&req
->work
, 0, sizeof(req
->work
));
1085 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1087 /* Grab a ref if this isn't our static identity */
1088 req
->work
.identity
= tctx
->identity
;
1089 if (tctx
->identity
!= &tctx
->__identity
)
1090 refcount_inc(&req
->work
.identity
->count
);
1093 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
1095 return ctx
->flags
& IORING_SETUP_SQPOLL
;
1098 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1100 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1102 complete(&ctx
->ref_comp
);
1105 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1107 return !req
->timeout
.off
;
1110 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1112 struct io_ring_ctx
*ctx
;
1115 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1119 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
1120 if (!ctx
->fallback_req
)
1124 * Use 5 bits less than the max cq entries, that should give us around
1125 * 32 entries per hash list if totally full and uniformly spread.
1127 hash_bits
= ilog2(p
->cq_entries
);
1131 ctx
->cancel_hash_bits
= hash_bits
;
1132 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1134 if (!ctx
->cancel_hash
)
1136 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1138 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1139 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1142 ctx
->flags
= p
->flags
;
1143 init_waitqueue_head(&ctx
->sqo_sq_wait
);
1144 INIT_LIST_HEAD(&ctx
->sqd_list
);
1145 init_waitqueue_head(&ctx
->cq_wait
);
1146 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1147 init_completion(&ctx
->ref_comp
);
1148 init_completion(&ctx
->sq_thread_comp
);
1149 idr_init(&ctx
->io_buffer_idr
);
1150 idr_init(&ctx
->personality_idr
);
1151 mutex_init(&ctx
->uring_lock
);
1152 init_waitqueue_head(&ctx
->wait
);
1153 spin_lock_init(&ctx
->completion_lock
);
1154 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1155 INIT_LIST_HEAD(&ctx
->defer_list
);
1156 INIT_LIST_HEAD(&ctx
->timeout_list
);
1157 init_waitqueue_head(&ctx
->inflight_wait
);
1158 spin_lock_init(&ctx
->inflight_lock
);
1159 INIT_LIST_HEAD(&ctx
->inflight_list
);
1160 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
1161 init_llist_head(&ctx
->file_put_llist
);
1164 if (ctx
->fallback_req
)
1165 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
1166 kfree(ctx
->cancel_hash
);
1171 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1173 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1174 struct io_ring_ctx
*ctx
= req
->ctx
;
1176 return seq
!= ctx
->cached_cq_tail
1177 + atomic_read(&ctx
->cached_cq_overflow
);
1183 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1185 struct io_rings
*rings
= ctx
->rings
;
1187 /* order cqe stores with ring update */
1188 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1190 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1191 wake_up_interruptible(&ctx
->cq_wait
);
1192 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1196 static void io_put_identity(struct io_uring_task
*tctx
, struct io_kiocb
*req
)
1198 if (req
->work
.identity
== &tctx
->__identity
)
1200 if (refcount_dec_and_test(&req
->work
.identity
->count
))
1201 kfree(req
->work
.identity
);
1204 static void io_req_clean_work(struct io_kiocb
*req
)
1206 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1209 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1211 if (req
->work
.flags
& IO_WQ_WORK_MM
) {
1212 mmdrop(req
->work
.identity
->mm
);
1213 req
->work
.flags
&= ~IO_WQ_WORK_MM
;
1215 #ifdef CONFIG_BLK_CGROUP
1216 if (req
->work
.flags
& IO_WQ_WORK_BLKCG
) {
1217 css_put(req
->work
.identity
->blkcg_css
);
1218 req
->work
.flags
&= ~IO_WQ_WORK_BLKCG
;
1221 if (req
->work
.flags
& IO_WQ_WORK_CREDS
) {
1222 put_cred(req
->work
.identity
->creds
);
1223 req
->work
.flags
&= ~IO_WQ_WORK_CREDS
;
1225 if (req
->work
.flags
& IO_WQ_WORK_FS
) {
1226 struct fs_struct
*fs
= req
->work
.identity
->fs
;
1228 spin_lock(&req
->work
.identity
->fs
->lock
);
1231 spin_unlock(&req
->work
.identity
->fs
->lock
);
1234 req
->work
.flags
&= ~IO_WQ_WORK_FS
;
1237 io_put_identity(req
->task
->io_uring
, req
);
1241 * Create a private copy of io_identity, since some fields don't match
1242 * the current context.
1244 static bool io_identity_cow(struct io_kiocb
*req
)
1246 struct io_uring_task
*tctx
= current
->io_uring
;
1247 const struct cred
*creds
= NULL
;
1248 struct io_identity
*id
;
1250 if (req
->work
.flags
& IO_WQ_WORK_CREDS
)
1251 creds
= req
->work
.identity
->creds
;
1253 id
= kmemdup(req
->work
.identity
, sizeof(*id
), GFP_KERNEL
);
1254 if (unlikely(!id
)) {
1255 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1260 * We can safely just re-init the creds we copied Either the field
1261 * matches the current one, or we haven't grabbed it yet. The only
1262 * exception is ->creds, through registered personalities, so handle
1263 * that one separately.
1265 io_init_identity(id
);
1267 req
->work
.identity
->creds
= creds
;
1269 /* add one for this request */
1270 refcount_inc(&id
->count
);
1272 /* drop old identity, assign new one. one ref for req, one for tctx */
1273 if (req
->work
.identity
!= tctx
->identity
&&
1274 refcount_sub_and_test(2, &req
->work
.identity
->count
))
1275 kfree(req
->work
.identity
);
1277 req
->work
.identity
= id
;
1278 tctx
->identity
= id
;
1282 static bool io_grab_identity(struct io_kiocb
*req
)
1284 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1285 struct io_identity
*id
= req
->work
.identity
;
1286 struct io_ring_ctx
*ctx
= req
->ctx
;
1288 if (def
->needs_fsize
&& id
->fsize
!= rlimit(RLIMIT_FSIZE
))
1291 if (!(req
->work
.flags
& IO_WQ_WORK_FILES
) &&
1292 (def
->work_flags
& IO_WQ_WORK_FILES
) &&
1293 !(req
->flags
& REQ_F_NO_FILE_TABLE
)) {
1294 if (id
->files
!= current
->files
||
1295 id
->nsproxy
!= current
->nsproxy
)
1297 atomic_inc(&id
->files
->count
);
1298 get_nsproxy(id
->nsproxy
);
1299 req
->flags
|= REQ_F_INFLIGHT
;
1301 spin_lock_irq(&ctx
->inflight_lock
);
1302 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
1303 spin_unlock_irq(&ctx
->inflight_lock
);
1304 req
->work
.flags
|= IO_WQ_WORK_FILES
;
1306 #ifdef CONFIG_BLK_CGROUP
1307 if (!(req
->work
.flags
& IO_WQ_WORK_BLKCG
) &&
1308 (def
->work_flags
& IO_WQ_WORK_BLKCG
)) {
1310 if (id
->blkcg_css
!= blkcg_css()) {
1315 * This should be rare, either the cgroup is dying or the task
1316 * is moving cgroups. Just punt to root for the handful of ios.
1318 if (css_tryget_online(id
->blkcg_css
))
1319 req
->work
.flags
|= IO_WQ_WORK_BLKCG
;
1323 if (!(req
->work
.flags
& IO_WQ_WORK_CREDS
)) {
1324 if (id
->creds
!= current_cred())
1326 get_cred(id
->creds
);
1327 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
1330 if (!uid_eq(current
->loginuid
, id
->loginuid
) ||
1331 current
->sessionid
!= id
->sessionid
)
1334 if (!(req
->work
.flags
& IO_WQ_WORK_FS
) &&
1335 (def
->work_flags
& IO_WQ_WORK_FS
)) {
1336 if (current
->fs
!= id
->fs
)
1338 spin_lock(&id
->fs
->lock
);
1339 if (!id
->fs
->in_exec
) {
1341 req
->work
.flags
|= IO_WQ_WORK_FS
;
1343 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1345 spin_unlock(¤t
->fs
->lock
);
1351 static void io_prep_async_work(struct io_kiocb
*req
)
1353 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1354 struct io_ring_ctx
*ctx
= req
->ctx
;
1355 struct io_identity
*id
;
1357 io_req_init_async(req
);
1358 id
= req
->work
.identity
;
1360 if (req
->flags
& REQ_F_ISREG
) {
1361 if (def
->hash_reg_file
|| (ctx
->flags
& IORING_SETUP_IOPOLL
))
1362 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1364 if (def
->unbound_nonreg_file
)
1365 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1368 /* ->mm can never change on us */
1369 if (!(req
->work
.flags
& IO_WQ_WORK_MM
) &&
1370 (def
->work_flags
& IO_WQ_WORK_MM
)) {
1372 req
->work
.flags
|= IO_WQ_WORK_MM
;
1375 /* if we fail grabbing identity, we must COW, regrab, and retry */
1376 if (io_grab_identity(req
))
1379 if (!io_identity_cow(req
))
1382 /* can't fail at this point */
1383 if (!io_grab_identity(req
))
1387 static void io_prep_async_link(struct io_kiocb
*req
)
1389 struct io_kiocb
*cur
;
1391 io_prep_async_work(req
);
1392 if (req
->flags
& REQ_F_LINK_HEAD
)
1393 list_for_each_entry(cur
, &req
->link_list
, link_list
)
1394 io_prep_async_work(cur
);
1397 static struct io_kiocb
*__io_queue_async_work(struct io_kiocb
*req
)
1399 struct io_ring_ctx
*ctx
= req
->ctx
;
1400 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1402 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1403 &req
->work
, req
->flags
);
1404 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1408 static void io_queue_async_work(struct io_kiocb
*req
)
1410 struct io_kiocb
*link
;
1412 /* init ->work of the whole link before punting */
1413 io_prep_async_link(req
);
1414 link
= __io_queue_async_work(req
);
1417 io_queue_linked_timeout(link
);
1420 static void io_kill_timeout(struct io_kiocb
*req
)
1422 struct io_timeout_data
*io
= req
->async_data
;
1425 ret
= hrtimer_try_to_cancel(&io
->timer
);
1427 atomic_set(&req
->ctx
->cq_timeouts
,
1428 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1429 list_del_init(&req
->timeout
.list
);
1430 io_cqring_fill_event(req
, 0);
1431 io_put_req_deferred(req
, 1);
1435 static bool io_task_match(struct io_kiocb
*req
, struct task_struct
*tsk
)
1437 struct io_ring_ctx
*ctx
= req
->ctx
;
1439 if (!tsk
|| req
->task
== tsk
)
1441 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
1442 if (ctx
->sq_data
&& req
->task
== ctx
->sq_data
->thread
)
1449 * Returns true if we found and killed one or more timeouts
1451 static bool io_kill_timeouts(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
)
1453 struct io_kiocb
*req
, *tmp
;
1456 spin_lock_irq(&ctx
->completion_lock
);
1457 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
) {
1458 if (io_task_match(req
, tsk
)) {
1459 io_kill_timeout(req
);
1463 spin_unlock_irq(&ctx
->completion_lock
);
1464 return canceled
!= 0;
1467 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1470 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1471 struct io_defer_entry
, list
);
1472 struct io_kiocb
*link
;
1474 if (req_need_defer(de
->req
, de
->seq
))
1476 list_del_init(&de
->list
);
1477 /* punt-init is done before queueing for defer */
1478 link
= __io_queue_async_work(de
->req
);
1480 __io_queue_linked_timeout(link
);
1481 /* drop submission reference */
1482 io_put_req_deferred(link
, 1);
1485 } while (!list_empty(&ctx
->defer_list
));
1488 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1490 while (!list_empty(&ctx
->timeout_list
)) {
1491 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1492 struct io_kiocb
, timeout
.list
);
1494 if (io_is_timeout_noseq(req
))
1496 if (req
->timeout
.target_seq
!= ctx
->cached_cq_tail
1497 - atomic_read(&ctx
->cq_timeouts
))
1500 list_del_init(&req
->timeout
.list
);
1501 io_kill_timeout(req
);
1505 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1507 io_flush_timeouts(ctx
);
1508 __io_commit_cqring(ctx
);
1510 if (unlikely(!list_empty(&ctx
->defer_list
)))
1511 __io_queue_deferred(ctx
);
1514 static inline bool io_sqring_full(struct io_ring_ctx
*ctx
)
1516 struct io_rings
*r
= ctx
->rings
;
1518 return READ_ONCE(r
->sq
.tail
) - ctx
->cached_sq_head
== r
->sq_ring_entries
;
1521 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1523 struct io_rings
*rings
= ctx
->rings
;
1526 tail
= ctx
->cached_cq_tail
;
1528 * writes to the cq entry need to come after reading head; the
1529 * control dependency is enough as we're using WRITE_ONCE to
1532 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1535 ctx
->cached_cq_tail
++;
1536 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1539 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1543 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1545 if (!ctx
->eventfd_async
)
1547 return io_wq_current_is_worker();
1550 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1552 if (waitqueue_active(&ctx
->wait
))
1553 wake_up(&ctx
->wait
);
1554 if (ctx
->sq_data
&& waitqueue_active(&ctx
->sq_data
->wait
))
1555 wake_up(&ctx
->sq_data
->wait
);
1556 if (io_should_trigger_evfd(ctx
))
1557 eventfd_signal(ctx
->cq_ev_fd
, 1);
1560 static void io_cqring_mark_overflow(struct io_ring_ctx
*ctx
)
1562 if (list_empty(&ctx
->cq_overflow_list
)) {
1563 clear_bit(0, &ctx
->sq_check_overflow
);
1564 clear_bit(0, &ctx
->cq_check_overflow
);
1565 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1569 static inline bool io_match_files(struct io_kiocb
*req
,
1570 struct files_struct
*files
)
1574 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) &&
1575 (req
->work
.flags
& IO_WQ_WORK_FILES
))
1576 return req
->work
.identity
->files
== files
;
1580 /* Returns true if there are no backlogged entries after the flush */
1581 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
,
1582 struct task_struct
*tsk
,
1583 struct files_struct
*files
)
1585 struct io_rings
*rings
= ctx
->rings
;
1586 struct io_kiocb
*req
, *tmp
;
1587 struct io_uring_cqe
*cqe
;
1588 unsigned long flags
;
1592 if (list_empty_careful(&ctx
->cq_overflow_list
))
1594 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1595 rings
->cq_ring_entries
))
1599 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1601 /* if force is set, the ring is going away. always drop after that */
1603 ctx
->cq_overflow_flushed
= 1;
1606 list_for_each_entry_safe(req
, tmp
, &ctx
->cq_overflow_list
, compl.list
) {
1607 if (tsk
&& req
->task
!= tsk
)
1609 if (!io_match_files(req
, files
))
1612 cqe
= io_get_cqring(ctx
);
1616 list_move(&req
->compl.list
, &list
);
1618 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1619 WRITE_ONCE(cqe
->res
, req
->result
);
1620 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1622 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1623 atomic_inc_return(&ctx
->cached_cq_overflow
));
1627 io_commit_cqring(ctx
);
1628 io_cqring_mark_overflow(ctx
);
1630 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1631 io_cqring_ev_posted(ctx
);
1633 while (!list_empty(&list
)) {
1634 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1635 list_del(&req
->compl.list
);
1642 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1644 struct io_ring_ctx
*ctx
= req
->ctx
;
1645 struct io_uring_cqe
*cqe
;
1647 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1650 * If we can't get a cq entry, userspace overflowed the
1651 * submission (by quite a lot). Increment the overflow count in
1654 cqe
= io_get_cqring(ctx
);
1656 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1657 WRITE_ONCE(cqe
->res
, res
);
1658 WRITE_ONCE(cqe
->flags
, cflags
);
1659 } else if (ctx
->cq_overflow_flushed
|| req
->task
->io_uring
->in_idle
) {
1661 * If we're in ring overflow flush mode, or in task cancel mode,
1662 * then we cannot store the request for later flushing, we need
1663 * to drop it on the floor.
1665 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1666 atomic_inc_return(&ctx
->cached_cq_overflow
));
1668 if (list_empty(&ctx
->cq_overflow_list
)) {
1669 set_bit(0, &ctx
->sq_check_overflow
);
1670 set_bit(0, &ctx
->cq_check_overflow
);
1671 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1675 req
->compl.cflags
= cflags
;
1676 refcount_inc(&req
->refs
);
1677 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1681 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1683 __io_cqring_fill_event(req
, res
, 0);
1686 static void io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1688 struct io_ring_ctx
*ctx
= req
->ctx
;
1689 unsigned long flags
;
1691 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1692 __io_cqring_fill_event(req
, res
, cflags
);
1693 io_commit_cqring(ctx
);
1694 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1696 io_cqring_ev_posted(ctx
);
1699 static void io_submit_flush_completions(struct io_comp_state
*cs
)
1701 struct io_ring_ctx
*ctx
= cs
->ctx
;
1703 spin_lock_irq(&ctx
->completion_lock
);
1704 while (!list_empty(&cs
->list
)) {
1705 struct io_kiocb
*req
;
1707 req
= list_first_entry(&cs
->list
, struct io_kiocb
, compl.list
);
1708 list_del(&req
->compl.list
);
1709 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
1712 * io_free_req() doesn't care about completion_lock unless one
1713 * of these flags is set. REQ_F_WORK_INITIALIZED is in the list
1714 * because of a potential deadlock with req->work.fs->lock
1716 if (req
->flags
& (REQ_F_FAIL_LINK
|REQ_F_LINK_TIMEOUT
1717 |REQ_F_WORK_INITIALIZED
)) {
1718 spin_unlock_irq(&ctx
->completion_lock
);
1720 spin_lock_irq(&ctx
->completion_lock
);
1725 io_commit_cqring(ctx
);
1726 spin_unlock_irq(&ctx
->completion_lock
);
1728 io_cqring_ev_posted(ctx
);
1732 static void __io_req_complete(struct io_kiocb
*req
, long res
, unsigned cflags
,
1733 struct io_comp_state
*cs
)
1736 io_cqring_add_event(req
, res
, cflags
);
1741 req
->compl.cflags
= cflags
;
1742 list_add_tail(&req
->compl.list
, &cs
->list
);
1744 io_submit_flush_completions(cs
);
1748 static void io_req_complete(struct io_kiocb
*req
, long res
)
1750 __io_req_complete(req
, res
, 0, NULL
);
1753 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1755 return req
== (struct io_kiocb
*)
1756 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1759 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1761 struct io_kiocb
*req
;
1763 req
= ctx
->fallback_req
;
1764 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1770 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1771 struct io_submit_state
*state
)
1773 if (!state
->free_reqs
) {
1774 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1778 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1779 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1782 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1783 * retry single alloc to be on the safe side.
1785 if (unlikely(ret
<= 0)) {
1786 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1787 if (!state
->reqs
[0])
1791 state
->free_reqs
= ret
;
1795 return state
->reqs
[state
->free_reqs
];
1797 return io_get_fallback_req(ctx
);
1800 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1804 percpu_ref_put(req
->fixed_file_refs
);
1809 static void io_dismantle_req(struct io_kiocb
*req
)
1813 if (req
->async_data
)
1814 kfree(req
->async_data
);
1816 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1818 io_req_clean_work(req
);
1821 static void __io_free_req(struct io_kiocb
*req
)
1823 struct io_uring_task
*tctx
= req
->task
->io_uring
;
1824 struct io_ring_ctx
*ctx
= req
->ctx
;
1826 io_dismantle_req(req
);
1828 percpu_counter_dec(&tctx
->inflight
);
1830 wake_up(&tctx
->wait
);
1831 put_task_struct(req
->task
);
1833 if (likely(!io_is_fallback_req(req
)))
1834 kmem_cache_free(req_cachep
, req
);
1836 clear_bit_unlock(0, (unsigned long *) &ctx
->fallback_req
);
1837 percpu_ref_put(&ctx
->refs
);
1840 static bool io_link_cancel_timeout(struct io_kiocb
*req
)
1842 struct io_timeout_data
*io
= req
->async_data
;
1843 struct io_ring_ctx
*ctx
= req
->ctx
;
1846 ret
= hrtimer_try_to_cancel(&io
->timer
);
1848 io_cqring_fill_event(req
, -ECANCELED
);
1849 io_commit_cqring(ctx
);
1850 req
->flags
&= ~REQ_F_LINK_HEAD
;
1851 io_put_req_deferred(req
, 1);
1858 static bool __io_kill_linked_timeout(struct io_kiocb
*req
)
1860 struct io_kiocb
*link
;
1863 if (list_empty(&req
->link_list
))
1865 link
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1866 if (link
->opcode
!= IORING_OP_LINK_TIMEOUT
)
1869 list_del_init(&link
->link_list
);
1870 wake_ev
= io_link_cancel_timeout(link
);
1871 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1875 static void io_kill_linked_timeout(struct io_kiocb
*req
)
1877 struct io_ring_ctx
*ctx
= req
->ctx
;
1878 unsigned long flags
;
1881 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1882 wake_ev
= __io_kill_linked_timeout(req
);
1883 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1886 io_cqring_ev_posted(ctx
);
1889 static struct io_kiocb
*io_req_link_next(struct io_kiocb
*req
)
1891 struct io_kiocb
*nxt
;
1894 * The list should never be empty when we are called here. But could
1895 * potentially happen if the chain is messed up, check to be on the
1898 if (unlikely(list_empty(&req
->link_list
)))
1901 nxt
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1902 list_del_init(&req
->link_list
);
1903 if (!list_empty(&nxt
->link_list
))
1904 nxt
->flags
|= REQ_F_LINK_HEAD
;
1909 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
1911 static void __io_fail_links(struct io_kiocb
*req
)
1913 struct io_ring_ctx
*ctx
= req
->ctx
;
1915 while (!list_empty(&req
->link_list
)) {
1916 struct io_kiocb
*link
= list_first_entry(&req
->link_list
,
1917 struct io_kiocb
, link_list
);
1919 list_del_init(&link
->link_list
);
1920 trace_io_uring_fail_link(req
, link
);
1922 io_cqring_fill_event(link
, -ECANCELED
);
1925 * It's ok to free under spinlock as they're not linked anymore,
1926 * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on
1929 if (link
->flags
& REQ_F_WORK_INITIALIZED
)
1930 io_put_req_deferred(link
, 2);
1932 io_double_put_req(link
);
1935 io_commit_cqring(ctx
);
1938 static void io_fail_links(struct io_kiocb
*req
)
1940 struct io_ring_ctx
*ctx
= req
->ctx
;
1941 unsigned long flags
;
1943 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1944 __io_fail_links(req
);
1945 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1947 io_cqring_ev_posted(ctx
);
1950 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
1952 req
->flags
&= ~REQ_F_LINK_HEAD
;
1953 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
1954 io_kill_linked_timeout(req
);
1957 * If LINK is set, we have dependent requests in this chain. If we
1958 * didn't fail this request, queue the first one up, moving any other
1959 * dependencies to the next request. In case of failure, fail the rest
1962 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
)))
1963 return io_req_link_next(req
);
1968 static struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
1970 if (likely(!(req
->flags
& REQ_F_LINK_HEAD
)))
1972 return __io_req_find_next(req
);
1975 static int io_req_task_work_add(struct io_kiocb
*req
, bool twa_signal_ok
)
1977 struct task_struct
*tsk
= req
->task
;
1978 struct io_ring_ctx
*ctx
= req
->ctx
;
1979 enum task_work_notify_mode notify
;
1982 if (tsk
->flags
& PF_EXITING
)
1986 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
1987 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
1988 * processing task_work. There's no reliable way to tell if TWA_RESUME
1992 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
) && twa_signal_ok
)
1993 notify
= TWA_SIGNAL
;
1995 ret
= task_work_add(tsk
, &req
->task_work
, notify
);
1997 wake_up_process(tsk
);
2002 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
2004 struct io_ring_ctx
*ctx
= req
->ctx
;
2006 spin_lock_irq(&ctx
->completion_lock
);
2007 io_cqring_fill_event(req
, error
);
2008 io_commit_cqring(ctx
);
2009 spin_unlock_irq(&ctx
->completion_lock
);
2011 io_cqring_ev_posted(ctx
);
2012 req_set_fail_links(req
);
2013 io_double_put_req(req
);
2016 static void io_req_task_cancel(struct callback_head
*cb
)
2018 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2019 struct io_ring_ctx
*ctx
= req
->ctx
;
2021 __io_req_task_cancel(req
, -ECANCELED
);
2022 percpu_ref_put(&ctx
->refs
);
2025 static void __io_req_task_submit(struct io_kiocb
*req
)
2027 struct io_ring_ctx
*ctx
= req
->ctx
;
2029 if (!__io_sq_thread_acquire_mm(ctx
)) {
2030 mutex_lock(&ctx
->uring_lock
);
2031 __io_queue_sqe(req
, NULL
);
2032 mutex_unlock(&ctx
->uring_lock
);
2034 __io_req_task_cancel(req
, -EFAULT
);
2038 static void io_req_task_submit(struct callback_head
*cb
)
2040 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2041 struct io_ring_ctx
*ctx
= req
->ctx
;
2043 __io_req_task_submit(req
);
2044 percpu_ref_put(&ctx
->refs
);
2047 static void io_req_task_queue(struct io_kiocb
*req
)
2051 init_task_work(&req
->task_work
, io_req_task_submit
);
2052 percpu_ref_get(&req
->ctx
->refs
);
2054 ret
= io_req_task_work_add(req
, true);
2055 if (unlikely(ret
)) {
2056 struct task_struct
*tsk
;
2058 init_task_work(&req
->task_work
, io_req_task_cancel
);
2059 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2060 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2061 wake_up_process(tsk
);
2065 static void io_queue_next(struct io_kiocb
*req
)
2067 struct io_kiocb
*nxt
= io_req_find_next(req
);
2070 io_req_task_queue(nxt
);
2073 static void io_free_req(struct io_kiocb
*req
)
2080 void *reqs
[IO_IOPOLL_BATCH
];
2083 struct task_struct
*task
;
2087 static inline void io_init_req_batch(struct req_batch
*rb
)
2094 static void __io_req_free_batch_flush(struct io_ring_ctx
*ctx
,
2095 struct req_batch
*rb
)
2097 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
2098 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
2102 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
2103 struct req_batch
*rb
)
2106 __io_req_free_batch_flush(ctx
, rb
);
2108 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2110 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2111 put_task_struct_many(rb
->task
, rb
->task_refs
);
2116 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
)
2118 if (unlikely(io_is_fallback_req(req
))) {
2122 if (req
->flags
& REQ_F_LINK_HEAD
)
2125 if (req
->task
!= rb
->task
) {
2127 struct io_uring_task
*tctx
= rb
->task
->io_uring
;
2129 percpu_counter_sub(&tctx
->inflight
, rb
->task_refs
);
2130 put_task_struct_many(rb
->task
, rb
->task_refs
);
2132 rb
->task
= req
->task
;
2137 io_dismantle_req(req
);
2138 rb
->reqs
[rb
->to_free
++] = req
;
2139 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
2140 __io_req_free_batch_flush(req
->ctx
, rb
);
2144 * Drop reference to request, return next in chain (if there is one) if this
2145 * was the last reference to this request.
2147 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
2149 struct io_kiocb
*nxt
= NULL
;
2151 if (refcount_dec_and_test(&req
->refs
)) {
2152 nxt
= io_req_find_next(req
);
2158 static void io_put_req(struct io_kiocb
*req
)
2160 if (refcount_dec_and_test(&req
->refs
))
2164 static void io_put_req_deferred_cb(struct callback_head
*cb
)
2166 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2171 static void io_free_req_deferred(struct io_kiocb
*req
)
2175 init_task_work(&req
->task_work
, io_put_req_deferred_cb
);
2176 ret
= io_req_task_work_add(req
, true);
2177 if (unlikely(ret
)) {
2178 struct task_struct
*tsk
;
2180 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2181 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
2182 wake_up_process(tsk
);
2186 static inline void io_put_req_deferred(struct io_kiocb
*req
, int refs
)
2188 if (refcount_sub_and_test(refs
, &req
->refs
))
2189 io_free_req_deferred(req
);
2192 static struct io_wq_work
*io_steal_work(struct io_kiocb
*req
)
2194 struct io_kiocb
*nxt
;
2197 * A ref is owned by io-wq in which context we're. So, if that's the
2198 * last one, it's safe to steal next work. False negatives are Ok,
2199 * it just will be re-punted async in io_put_work()
2201 if (refcount_read(&req
->refs
) != 1)
2204 nxt
= io_req_find_next(req
);
2205 return nxt
? &nxt
->work
: NULL
;
2208 static void io_double_put_req(struct io_kiocb
*req
)
2210 /* drop both submit and complete references */
2211 if (refcount_sub_and_test(2, &req
->refs
))
2215 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
2217 struct io_rings
*rings
= ctx
->rings
;
2219 if (test_bit(0, &ctx
->cq_check_overflow
)) {
2221 * noflush == true is from the waitqueue handler, just ensure
2222 * we wake up the task, and the next invocation will flush the
2223 * entries. We cannot safely to it from here.
2225 if (noflush
&& !list_empty(&ctx
->cq_overflow_list
))
2228 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
2231 /* See comment at the top of this file */
2233 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
2236 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
2238 struct io_rings
*rings
= ctx
->rings
;
2240 /* make sure SQ entry isn't read before tail */
2241 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
2244 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
2246 unsigned int cflags
;
2248 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
2249 cflags
|= IORING_CQE_F_BUFFER
;
2250 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2255 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2257 struct io_buffer
*kbuf
;
2259 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2260 return io_put_kbuf(req
, kbuf
);
2263 static inline bool io_run_task_work(void)
2266 * Not safe to run on exiting task, and the task_work handling will
2267 * not add work to such a task.
2269 if (unlikely(current
->flags
& PF_EXITING
))
2271 if (current
->task_works
) {
2272 __set_current_state(TASK_RUNNING
);
2280 static void io_iopoll_queue(struct list_head
*again
)
2282 struct io_kiocb
*req
;
2285 req
= list_first_entry(again
, struct io_kiocb
, inflight_entry
);
2286 list_del(&req
->inflight_entry
);
2287 __io_complete_rw(req
, -EAGAIN
, 0, NULL
);
2288 } while (!list_empty(again
));
2292 * Find and free completed poll iocbs
2294 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2295 struct list_head
*done
)
2297 struct req_batch rb
;
2298 struct io_kiocb
*req
;
2301 /* order with ->result store in io_complete_rw_iopoll() */
2304 io_init_req_batch(&rb
);
2305 while (!list_empty(done
)) {
2308 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2309 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2311 req
->iopoll_completed
= 0;
2312 list_move_tail(&req
->inflight_entry
, &again
);
2315 list_del(&req
->inflight_entry
);
2317 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2318 cflags
= io_put_rw_kbuf(req
);
2320 __io_cqring_fill_event(req
, req
->result
, cflags
);
2323 if (refcount_dec_and_test(&req
->refs
))
2324 io_req_free_batch(&rb
, req
);
2327 io_commit_cqring(ctx
);
2328 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
2329 io_cqring_ev_posted(ctx
);
2330 io_req_free_batch_finish(ctx
, &rb
);
2332 if (!list_empty(&again
))
2333 io_iopoll_queue(&again
);
2336 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2339 struct io_kiocb
*req
, *tmp
;
2345 * Only spin for completions if we don't have multiple devices hanging
2346 * off our complete list, and we're under the requested amount.
2348 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2351 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2352 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2355 * Move completed and retryable entries to our local lists.
2356 * If we find a request that requires polling, break out
2357 * and complete those lists first, if we have entries there.
2359 if (READ_ONCE(req
->iopoll_completed
)) {
2360 list_move_tail(&req
->inflight_entry
, &done
);
2363 if (!list_empty(&done
))
2366 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2370 /* iopoll may have completed current req */
2371 if (READ_ONCE(req
->iopoll_completed
))
2372 list_move_tail(&req
->inflight_entry
, &done
);
2379 if (!list_empty(&done
))
2380 io_iopoll_complete(ctx
, nr_events
, &done
);
2386 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2387 * non-spinning poll check - we'll still enter the driver poll loop, but only
2388 * as a non-spinning completion check.
2390 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2393 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2396 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2399 if (*nr_events
>= min
)
2407 * We can't just wait for polled events to come to us, we have to actively
2408 * find and complete them.
2410 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2412 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2415 mutex_lock(&ctx
->uring_lock
);
2416 while (!list_empty(&ctx
->iopoll_list
)) {
2417 unsigned int nr_events
= 0;
2419 io_do_iopoll(ctx
, &nr_events
, 0);
2421 /* let it sleep and repeat later if can't complete a request */
2425 * Ensure we allow local-to-the-cpu processing to take place,
2426 * in this case we need to ensure that we reap all events.
2427 * Also let task_work, etc. to progress by releasing the mutex
2429 if (need_resched()) {
2430 mutex_unlock(&ctx
->uring_lock
);
2432 mutex_lock(&ctx
->uring_lock
);
2435 mutex_unlock(&ctx
->uring_lock
);
2438 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2440 unsigned int nr_events
= 0;
2441 int iters
= 0, ret
= 0;
2444 * We disallow the app entering submit/complete with polling, but we
2445 * still need to lock the ring to prevent racing with polled issue
2446 * that got punted to a workqueue.
2448 mutex_lock(&ctx
->uring_lock
);
2451 * Don't enter poll loop if we already have events pending.
2452 * If we do, we can potentially be spinning for commands that
2453 * already triggered a CQE (eg in error).
2455 if (io_cqring_events(ctx
, false))
2459 * If a submit got punted to a workqueue, we can have the
2460 * application entering polling for a command before it gets
2461 * issued. That app will hold the uring_lock for the duration
2462 * of the poll right here, so we need to take a breather every
2463 * now and then to ensure that the issue has a chance to add
2464 * the poll to the issued list. Otherwise we can spin here
2465 * forever, while the workqueue is stuck trying to acquire the
2468 if (!(++iters
& 7)) {
2469 mutex_unlock(&ctx
->uring_lock
);
2471 mutex_lock(&ctx
->uring_lock
);
2474 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2478 } while (min
&& !nr_events
&& !need_resched());
2480 mutex_unlock(&ctx
->uring_lock
);
2484 static void kiocb_end_write(struct io_kiocb
*req
)
2487 * Tell lockdep we inherited freeze protection from submission
2490 if (req
->flags
& REQ_F_ISREG
) {
2491 struct inode
*inode
= file_inode(req
->file
);
2493 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2495 file_end_write(req
->file
);
2498 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
,
2499 struct io_comp_state
*cs
)
2501 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2504 if (kiocb
->ki_flags
& IOCB_WRITE
)
2505 kiocb_end_write(req
);
2507 if (res
!= req
->result
)
2508 req_set_fail_links(req
);
2509 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2510 cflags
= io_put_rw_kbuf(req
);
2511 __io_req_complete(req
, res
, cflags
, cs
);
2515 static bool io_resubmit_prep(struct io_kiocb
*req
, int error
)
2517 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2518 ssize_t ret
= -ECANCELED
;
2519 struct iov_iter iter
;
2527 switch (req
->opcode
) {
2528 case IORING_OP_READV
:
2529 case IORING_OP_READ_FIXED
:
2530 case IORING_OP_READ
:
2533 case IORING_OP_WRITEV
:
2534 case IORING_OP_WRITE_FIXED
:
2535 case IORING_OP_WRITE
:
2539 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2544 if (!req
->async_data
) {
2545 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2548 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, &iter
, false);
2556 req_set_fail_links(req
);
2557 io_req_complete(req
, ret
);
2562 static bool io_rw_reissue(struct io_kiocb
*req
, long res
)
2565 umode_t mode
= file_inode(req
->file
)->i_mode
;
2568 if (!S_ISBLK(mode
) && !S_ISREG(mode
))
2570 if ((res
!= -EAGAIN
&& res
!= -EOPNOTSUPP
) || io_wq_current_is_worker())
2573 ret
= io_sq_thread_acquire_mm(req
->ctx
, req
);
2575 if (io_resubmit_prep(req
, ret
)) {
2576 refcount_inc(&req
->refs
);
2577 io_queue_async_work(req
);
2585 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2586 struct io_comp_state
*cs
)
2588 if (!io_rw_reissue(req
, res
))
2589 io_complete_rw_common(&req
->rw
.kiocb
, res
, cs
);
2592 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2594 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2596 __io_complete_rw(req
, res
, res2
, NULL
);
2599 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2601 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2603 if (kiocb
->ki_flags
& IOCB_WRITE
)
2604 kiocb_end_write(req
);
2606 if (res
!= -EAGAIN
&& res
!= req
->result
)
2607 req_set_fail_links(req
);
2609 WRITE_ONCE(req
->result
, res
);
2610 /* order with io_poll_complete() checking ->result */
2612 WRITE_ONCE(req
->iopoll_completed
, 1);
2616 * After the iocb has been issued, it's safe to be found on the poll list.
2617 * Adding the kiocb to the list AFTER submission ensures that we don't
2618 * find it from a io_iopoll_getevents() thread before the issuer is done
2619 * accessing the kiocb cookie.
2621 static void io_iopoll_req_issued(struct io_kiocb
*req
)
2623 struct io_ring_ctx
*ctx
= req
->ctx
;
2626 * Track whether we have multiple files in our lists. This will impact
2627 * how we do polling eventually, not spinning if we're on potentially
2628 * different devices.
2630 if (list_empty(&ctx
->iopoll_list
)) {
2631 ctx
->poll_multi_file
= false;
2632 } else if (!ctx
->poll_multi_file
) {
2633 struct io_kiocb
*list_req
;
2635 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2637 if (list_req
->file
!= req
->file
)
2638 ctx
->poll_multi_file
= true;
2642 * For fast devices, IO may have already completed. If it has, add
2643 * it to the front so we find it first.
2645 if (READ_ONCE(req
->iopoll_completed
))
2646 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2648 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2650 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2651 wq_has_sleeper(&ctx
->sq_data
->wait
))
2652 wake_up(&ctx
->sq_data
->wait
);
2655 static void __io_state_file_put(struct io_submit_state
*state
)
2657 if (state
->has_refs
)
2658 fput_many(state
->file
, state
->has_refs
);
2662 static inline void io_state_file_put(struct io_submit_state
*state
)
2665 __io_state_file_put(state
);
2669 * Get as many references to a file as we have IOs left in this submission,
2670 * assuming most submissions are for one file, or at least that each file
2671 * has more than one submission.
2673 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2679 if (state
->fd
== fd
) {
2683 __io_state_file_put(state
);
2685 state
->file
= fget_many(fd
, state
->ios_left
);
2690 state
->has_refs
= state
->ios_left
- 1;
2694 static bool io_bdev_nowait(struct block_device
*bdev
)
2697 return !bdev
|| blk_queue_nowait(bdev_get_queue(bdev
));
2704 * If we tracked the file through the SCM inflight mechanism, we could support
2705 * any file. For now, just ensure that anything potentially problematic is done
2708 static bool io_file_supports_async(struct file
*file
, int rw
)
2710 umode_t mode
= file_inode(file
)->i_mode
;
2712 if (S_ISBLK(mode
)) {
2713 if (io_bdev_nowait(file
->f_inode
->i_bdev
))
2717 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2719 if (S_ISREG(mode
)) {
2720 if (io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2721 file
->f_op
!= &io_uring_fops
)
2726 /* any ->read/write should understand O_NONBLOCK */
2727 if (file
->f_flags
& O_NONBLOCK
)
2730 if (!(file
->f_mode
& FMODE_NOWAIT
))
2734 return file
->f_op
->read_iter
!= NULL
;
2736 return file
->f_op
->write_iter
!= NULL
;
2739 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2741 struct io_ring_ctx
*ctx
= req
->ctx
;
2742 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2746 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2747 req
->flags
|= REQ_F_ISREG
;
2749 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2750 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2751 req
->flags
|= REQ_F_CUR_POS
;
2752 kiocb
->ki_pos
= req
->file
->f_pos
;
2754 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2755 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2756 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2760 ioprio
= READ_ONCE(sqe
->ioprio
);
2762 ret
= ioprio_check_cap(ioprio
);
2766 kiocb
->ki_ioprio
= ioprio
;
2768 kiocb
->ki_ioprio
= get_current_ioprio();
2770 /* don't allow async punt if RWF_NOWAIT was requested */
2771 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2772 req
->flags
|= REQ_F_NOWAIT
;
2774 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2775 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2776 !kiocb
->ki_filp
->f_op
->iopoll
)
2779 kiocb
->ki_flags
|= IOCB_HIPRI
;
2780 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2781 req
->iopoll_completed
= 0;
2783 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2785 kiocb
->ki_complete
= io_complete_rw
;
2788 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2789 req
->rw
.len
= READ_ONCE(sqe
->len
);
2790 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2794 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2800 case -ERESTARTNOINTR
:
2801 case -ERESTARTNOHAND
:
2802 case -ERESTART_RESTARTBLOCK
:
2804 * We can't just restart the syscall, since previously
2805 * submitted sqes may already be in progress. Just fail this
2811 kiocb
->ki_complete(kiocb
, ret
, 0);
2815 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2816 struct io_comp_state
*cs
)
2818 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2819 struct io_async_rw
*io
= req
->async_data
;
2821 /* add previously done IO, if any */
2822 if (io
&& io
->bytes_done
> 0) {
2824 ret
= io
->bytes_done
;
2826 ret
+= io
->bytes_done
;
2829 if (req
->flags
& REQ_F_CUR_POS
)
2830 req
->file
->f_pos
= kiocb
->ki_pos
;
2831 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2832 __io_complete_rw(req
, ret
, 0, cs
);
2834 io_rw_done(kiocb
, ret
);
2837 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2838 struct iov_iter
*iter
)
2840 struct io_ring_ctx
*ctx
= req
->ctx
;
2841 size_t len
= req
->rw
.len
;
2842 struct io_mapped_ubuf
*imu
;
2843 u16 index
, buf_index
= req
->buf_index
;
2847 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2849 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2850 imu
= &ctx
->user_bufs
[index
];
2851 buf_addr
= req
->rw
.addr
;
2854 if (buf_addr
+ len
< buf_addr
)
2856 /* not inside the mapped region */
2857 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2861 * May not be a start of buffer, set size appropriately
2862 * and advance us to the beginning.
2864 offset
= buf_addr
- imu
->ubuf
;
2865 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2869 * Don't use iov_iter_advance() here, as it's really slow for
2870 * using the latter parts of a big fixed buffer - it iterates
2871 * over each segment manually. We can cheat a bit here, because
2874 * 1) it's a BVEC iter, we set it up
2875 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2876 * first and last bvec
2878 * So just find our index, and adjust the iterator afterwards.
2879 * If the offset is within the first bvec (or the whole first
2880 * bvec, just use iov_iter_advance(). This makes it easier
2881 * since we can just skip the first segment, which may not
2882 * be PAGE_SIZE aligned.
2884 const struct bio_vec
*bvec
= imu
->bvec
;
2886 if (offset
<= bvec
->bv_len
) {
2887 iov_iter_advance(iter
, offset
);
2889 unsigned long seg_skip
;
2891 /* skip first vec */
2892 offset
-= bvec
->bv_len
;
2893 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2895 iter
->bvec
= bvec
+ seg_skip
;
2896 iter
->nr_segs
-= seg_skip
;
2897 iter
->count
-= bvec
->bv_len
+ offset
;
2898 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2905 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2908 mutex_unlock(&ctx
->uring_lock
);
2911 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2914 * "Normal" inline submissions always hold the uring_lock, since we
2915 * grab it from the system call. Same is true for the SQPOLL offload.
2916 * The only exception is when we've detached the request and issue it
2917 * from an async worker thread, grab the lock for that case.
2920 mutex_lock(&ctx
->uring_lock
);
2923 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2924 int bgid
, struct io_buffer
*kbuf
,
2927 struct io_buffer
*head
;
2929 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2932 io_ring_submit_lock(req
->ctx
, needs_lock
);
2934 lockdep_assert_held(&req
->ctx
->uring_lock
);
2936 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
2938 if (!list_empty(&head
->list
)) {
2939 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2941 list_del(&kbuf
->list
);
2944 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
2946 if (*len
> kbuf
->len
)
2949 kbuf
= ERR_PTR(-ENOBUFS
);
2952 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2957 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2960 struct io_buffer
*kbuf
;
2963 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2964 bgid
= req
->buf_index
;
2965 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2968 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2969 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2970 return u64_to_user_ptr(kbuf
->addr
);
2973 #ifdef CONFIG_COMPAT
2974 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2977 struct compat_iovec __user
*uiov
;
2978 compat_ssize_t clen
;
2982 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2983 if (!access_ok(uiov
, sizeof(*uiov
)))
2985 if (__get_user(clen
, &uiov
->iov_len
))
2991 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2993 return PTR_ERR(buf
);
2994 iov
[0].iov_base
= buf
;
2995 iov
[0].iov_len
= (compat_size_t
) len
;
3000 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3003 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
3007 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
3010 len
= iov
[0].iov_len
;
3013 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
3015 return PTR_ERR(buf
);
3016 iov
[0].iov_base
= buf
;
3017 iov
[0].iov_len
= len
;
3021 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
3024 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
3025 struct io_buffer
*kbuf
;
3027 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
3028 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3029 iov
[0].iov_len
= kbuf
->len
;
3034 else if (req
->rw
.len
> 1)
3037 #ifdef CONFIG_COMPAT
3038 if (req
->ctx
->compat
)
3039 return io_compat_import(req
, iov
, needs_lock
);
3042 return __io_iov_buffer_select(req
, iov
, needs_lock
);
3045 static ssize_t
__io_import_iovec(int rw
, struct io_kiocb
*req
,
3046 struct iovec
**iovec
, struct iov_iter
*iter
,
3049 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
3050 size_t sqe_len
= req
->rw
.len
;
3054 opcode
= req
->opcode
;
3055 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
3057 return io_import_fixed(req
, rw
, iter
);
3060 /* buffer index only valid with fixed read/write, or buffer select */
3061 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
3064 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
3065 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3066 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
3068 return PTR_ERR(buf
);
3069 req
->rw
.len
= sqe_len
;
3072 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
3074 return ret
< 0 ? ret
: sqe_len
;
3077 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3078 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
3080 ret
= (*iovec
)->iov_len
;
3081 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
3087 return __import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
,
3091 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
3092 struct iovec
**iovec
, struct iov_iter
*iter
,
3095 struct io_async_rw
*iorw
= req
->async_data
;
3098 return __io_import_iovec(rw
, req
, iovec
, iter
, needs_lock
);
3100 return iov_iter_count(&iorw
->iter
);
3103 static inline loff_t
*io_kiocb_ppos(struct kiocb
*kiocb
)
3105 return (kiocb
->ki_filp
->f_mode
& FMODE_STREAM
) ? NULL
: &kiocb
->ki_pos
;
3109 * For files that don't have ->read_iter() and ->write_iter(), handle them
3110 * by looping over ->read() or ->write() manually.
3112 static ssize_t
loop_rw_iter(int rw
, struct file
*file
, struct kiocb
*kiocb
,
3113 struct iov_iter
*iter
)
3118 * Don't support polled IO through this interface, and we can't
3119 * support non-blocking either. For the latter, this just causes
3120 * the kiocb to be handled from an async context.
3122 if (kiocb
->ki_flags
& IOCB_HIPRI
)
3124 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
3127 while (iov_iter_count(iter
)) {
3131 if (!iov_iter_is_bvec(iter
)) {
3132 iovec
= iov_iter_iovec(iter
);
3134 /* fixed buffers import bvec */
3135 iovec
.iov_base
= kmap(iter
->bvec
->bv_page
)
3137 iovec
.iov_len
= min(iter
->count
,
3138 iter
->bvec
->bv_len
- iter
->iov_offset
);
3142 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
3143 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3145 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
3146 iovec
.iov_len
, io_kiocb_ppos(kiocb
));
3149 if (iov_iter_is_bvec(iter
))
3150 kunmap(iter
->bvec
->bv_page
);
3158 if (nr
!= iovec
.iov_len
)
3160 iov_iter_advance(iter
, nr
);
3166 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3167 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
3169 struct io_async_rw
*rw
= req
->async_data
;
3171 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
3172 rw
->free_iovec
= iovec
;
3174 /* can only be fixed buffers, no need to do anything */
3175 if (iter
->type
== ITER_BVEC
)
3178 unsigned iov_off
= 0;
3180 rw
->iter
.iov
= rw
->fast_iov
;
3181 if (iter
->iov
!= fast_iov
) {
3182 iov_off
= iter
->iov
- fast_iov
;
3183 rw
->iter
.iov
+= iov_off
;
3185 if (rw
->fast_iov
!= fast_iov
)
3186 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
3187 sizeof(struct iovec
) * iter
->nr_segs
);
3189 req
->flags
|= REQ_F_NEED_CLEANUP
;
3193 static inline int __io_alloc_async_data(struct io_kiocb
*req
)
3195 WARN_ON_ONCE(!io_op_defs
[req
->opcode
].async_size
);
3196 req
->async_data
= kmalloc(io_op_defs
[req
->opcode
].async_size
, GFP_KERNEL
);
3197 return req
->async_data
== NULL
;
3200 static int io_alloc_async_data(struct io_kiocb
*req
)
3202 if (!io_op_defs
[req
->opcode
].needs_async_data
)
3205 return __io_alloc_async_data(req
);
3208 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
3209 const struct iovec
*fast_iov
,
3210 struct iov_iter
*iter
, bool force
)
3212 if (!force
&& !io_op_defs
[req
->opcode
].needs_async_data
)
3214 if (!req
->async_data
) {
3215 if (__io_alloc_async_data(req
))
3218 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
3223 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
)
3225 struct io_async_rw
*iorw
= req
->async_data
;
3226 struct iovec
*iov
= iorw
->fast_iov
;
3229 ret
= __io_import_iovec(rw
, req
, &iov
, &iorw
->iter
, false);
3230 if (unlikely(ret
< 0))
3233 iorw
->bytes_done
= 0;
3234 iorw
->free_iovec
= iov
;
3236 req
->flags
|= REQ_F_NEED_CLEANUP
;
3240 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3244 ret
= io_prep_rw(req
, sqe
);
3248 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3251 /* either don't need iovec imported or already have it */
3252 if (!req
->async_data
)
3254 return io_rw_prep_async(req
, READ
);
3258 * This is our waitqueue callback handler, registered through lock_page_async()
3259 * when we initially tried to do the IO with the iocb armed our waitqueue.
3260 * This gets called when the page is unlocked, and we generally expect that to
3261 * happen when the page IO is completed and the page is now uptodate. This will
3262 * queue a task_work based retry of the operation, attempting to copy the data
3263 * again. If the latter fails because the page was NOT uptodate, then we will
3264 * do a thread based blocking retry of the operation. That's the unexpected
3267 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3268 int sync
, void *arg
)
3270 struct wait_page_queue
*wpq
;
3271 struct io_kiocb
*req
= wait
->private;
3272 struct wait_page_key
*key
= arg
;
3275 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3277 if (!wake_page_match(wpq
, key
))
3280 req
->rw
.kiocb
.ki_flags
&= ~IOCB_WAITQ
;
3281 list_del_init(&wait
->entry
);
3283 init_task_work(&req
->task_work
, io_req_task_submit
);
3284 percpu_ref_get(&req
->ctx
->refs
);
3286 /* submit ref gets dropped, acquire a new one */
3287 refcount_inc(&req
->refs
);
3288 ret
= io_req_task_work_add(req
, true);
3289 if (unlikely(ret
)) {
3290 struct task_struct
*tsk
;
3292 /* queue just for cancelation */
3293 init_task_work(&req
->task_work
, io_req_task_cancel
);
3294 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
3295 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
3296 wake_up_process(tsk
);
3302 * This controls whether a given IO request should be armed for async page
3303 * based retry. If we return false here, the request is handed to the async
3304 * worker threads for retry. If we're doing buffered reads on a regular file,
3305 * we prepare a private wait_page_queue entry and retry the operation. This
3306 * will either succeed because the page is now uptodate and unlocked, or it
3307 * will register a callback when the page is unlocked at IO completion. Through
3308 * that callback, io_uring uses task_work to setup a retry of the operation.
3309 * That retry will attempt the buffered read again. The retry will generally
3310 * succeed, or in rare cases where it fails, we then fall back to using the
3311 * async worker threads for a blocking retry.
3313 static bool io_rw_should_retry(struct io_kiocb
*req
)
3315 struct io_async_rw
*rw
= req
->async_data
;
3316 struct wait_page_queue
*wait
= &rw
->wpq
;
3317 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3319 /* never retry for NOWAIT, we just complete with -EAGAIN */
3320 if (req
->flags
& REQ_F_NOWAIT
)
3323 /* Only for buffered IO */
3324 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3328 * just use poll if we can, and don't attempt if the fs doesn't
3329 * support callback based unlocks
3331 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3334 wait
->wait
.func
= io_async_buf_func
;
3335 wait
->wait
.private = req
;
3336 wait
->wait
.flags
= 0;
3337 INIT_LIST_HEAD(&wait
->wait
.entry
);
3338 kiocb
->ki_flags
|= IOCB_WAITQ
;
3339 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3340 kiocb
->ki_waitq
= wait
;
3344 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3346 if (req
->file
->f_op
->read_iter
)
3347 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3348 else if (req
->file
->f_op
->read
)
3349 return loop_rw_iter(READ
, req
->file
, &req
->rw
.kiocb
, iter
);
3354 static int io_read(struct io_kiocb
*req
, bool force_nonblock
,
3355 struct io_comp_state
*cs
)
3357 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3358 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3359 struct iov_iter __iter
, *iter
= &__iter
;
3360 struct io_async_rw
*rw
= req
->async_data
;
3361 ssize_t io_size
, ret
, ret2
;
3368 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3371 iov_count
= iov_iter_count(iter
);
3373 req
->result
= io_size
;
3376 /* Ensure we clear previously set non-block flag */
3377 if (!force_nonblock
)
3378 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3380 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3383 /* If the file doesn't support async, just async punt */
3384 no_async
= force_nonblock
&& !io_file_supports_async(req
->file
, READ
);
3388 ret
= rw_verify_area(READ
, req
->file
, io_kiocb_ppos(kiocb
), iov_count
);
3392 ret
= io_iter_do_read(req
, iter
);
3396 } else if (ret
== -EIOCBQUEUED
) {
3399 } else if (ret
== -EAGAIN
) {
3400 /* IOPOLL retry should happen for io-wq threads */
3401 if (!force_nonblock
&& !(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3403 /* no retry on NONBLOCK marked file */
3404 if (req
->file
->f_flags
& O_NONBLOCK
)
3406 /* some cases will consume bytes even on error returns */
3407 iov_iter_revert(iter
, iov_count
- iov_iter_count(iter
));
3410 } else if (ret
< 0) {
3411 /* make sure -ERESTARTSYS -> -EINTR is done */
3415 /* read it all, or we did blocking attempt. no retry. */
3416 if (!iov_iter_count(iter
) || !force_nonblock
||
3417 (req
->file
->f_flags
& O_NONBLOCK
))
3422 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3429 rw
= req
->async_data
;
3430 /* it's copied and will be cleaned with ->io */
3432 /* now use our persistent iterator, if we aren't already */
3435 rw
->bytes_done
+= ret
;
3436 /* if we can retry, do so with the callbacks armed */
3437 if (!io_rw_should_retry(req
)) {
3438 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3443 * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
3444 * get -EIOCBQUEUED, then we'll get a notification when the desired
3445 * page gets unlocked. We can also get a partial read here, and if we
3446 * do, then just retry at the new offset.
3448 ret
= io_iter_do_read(req
, iter
);
3449 if (ret
== -EIOCBQUEUED
) {
3452 } else if (ret
> 0 && ret
< io_size
) {
3453 /* we got some bytes, but not all. retry. */
3457 kiocb_done(kiocb
, ret
, cs
);
3460 /* it's reportedly faster than delegating the null check to kfree() */
3466 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3470 ret
= io_prep_rw(req
, sqe
);
3474 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3477 /* either don't need iovec imported or already have it */
3478 if (!req
->async_data
)
3480 return io_rw_prep_async(req
, WRITE
);
3483 static int io_write(struct io_kiocb
*req
, bool force_nonblock
,
3484 struct io_comp_state
*cs
)
3486 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3487 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3488 struct iov_iter __iter
, *iter
= &__iter
;
3489 struct io_async_rw
*rw
= req
->async_data
;
3491 ssize_t ret
, ret2
, io_size
;
3496 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3499 iov_count
= iov_iter_count(iter
);
3501 req
->result
= io_size
;
3503 /* Ensure we clear previously set non-block flag */
3504 if (!force_nonblock
)
3505 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3507 kiocb
->ki_flags
|= IOCB_NOWAIT
;
3509 /* If the file doesn't support async, just async punt */
3510 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3513 /* file path doesn't support NOWAIT for non-direct_IO */
3514 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3515 (req
->flags
& REQ_F_ISREG
))
3518 ret
= rw_verify_area(WRITE
, req
->file
, io_kiocb_ppos(kiocb
), iov_count
);
3523 * Open-code file_start_write here to grab freeze protection,
3524 * which will be released by another thread in
3525 * io_complete_rw(). Fool lockdep by telling it the lock got
3526 * released so that it doesn't complain about the held lock when
3527 * we return to userspace.
3529 if (req
->flags
& REQ_F_ISREG
) {
3530 __sb_start_write(file_inode(req
->file
)->i_sb
,
3531 SB_FREEZE_WRITE
, true);
3532 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3535 kiocb
->ki_flags
|= IOCB_WRITE
;
3537 if (req
->file
->f_op
->write_iter
)
3538 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3539 else if (req
->file
->f_op
->write
)
3540 ret2
= loop_rw_iter(WRITE
, req
->file
, kiocb
, iter
);
3545 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3546 * retry them without IOCB_NOWAIT.
3548 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3550 /* no retry on NONBLOCK marked file */
3551 if (ret2
== -EAGAIN
&& (req
->file
->f_flags
& O_NONBLOCK
))
3553 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3554 /* IOPOLL retry should happen for io-wq threads */
3555 if ((req
->ctx
->flags
& IORING_SETUP_IOPOLL
) && ret2
== -EAGAIN
)
3558 kiocb_done(kiocb
, ret2
, cs
);
3561 /* some cases will consume bytes even on error returns */
3562 iov_iter_revert(iter
, iov_count
- iov_iter_count(iter
));
3563 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3568 /* it's reportedly faster than delegating the null check to kfree() */
3574 static int __io_splice_prep(struct io_kiocb
*req
,
3575 const struct io_uring_sqe
*sqe
)
3577 struct io_splice
* sp
= &req
->splice
;
3578 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3580 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3584 sp
->len
= READ_ONCE(sqe
->len
);
3585 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3587 if (unlikely(sp
->flags
& ~valid_flags
))
3590 sp
->file_in
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
),
3591 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3594 req
->flags
|= REQ_F_NEED_CLEANUP
;
3596 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3598 * Splice operation will be punted aync, and here need to
3599 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3601 io_req_init_async(req
);
3602 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3608 static int io_tee_prep(struct io_kiocb
*req
,
3609 const struct io_uring_sqe
*sqe
)
3611 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3613 return __io_splice_prep(req
, sqe
);
3616 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
3618 struct io_splice
*sp
= &req
->splice
;
3619 struct file
*in
= sp
->file_in
;
3620 struct file
*out
= sp
->file_out
;
3621 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3627 ret
= do_tee(in
, out
, sp
->len
, flags
);
3629 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3630 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3633 req_set_fail_links(req
);
3634 io_req_complete(req
, ret
);
3638 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3640 struct io_splice
* sp
= &req
->splice
;
3642 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3643 sp
->off_out
= READ_ONCE(sqe
->off
);
3644 return __io_splice_prep(req
, sqe
);
3647 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
3649 struct io_splice
*sp
= &req
->splice
;
3650 struct file
*in
= sp
->file_in
;
3651 struct file
*out
= sp
->file_out
;
3652 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3653 loff_t
*poff_in
, *poff_out
;
3659 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3660 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3663 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3665 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3666 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3669 req_set_fail_links(req
);
3670 io_req_complete(req
, ret
);
3675 * IORING_OP_NOP just posts a completion event, nothing else.
3677 static int io_nop(struct io_kiocb
*req
, struct io_comp_state
*cs
)
3679 struct io_ring_ctx
*ctx
= req
->ctx
;
3681 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3684 __io_req_complete(req
, 0, 0, cs
);
3688 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3690 struct io_ring_ctx
*ctx
= req
->ctx
;
3695 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3697 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3700 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3701 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3704 req
->sync
.off
= READ_ONCE(sqe
->off
);
3705 req
->sync
.len
= READ_ONCE(sqe
->len
);
3709 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
3711 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3714 /* fsync always requires a blocking context */
3718 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3719 end
> 0 ? end
: LLONG_MAX
,
3720 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3722 req_set_fail_links(req
);
3723 io_req_complete(req
, ret
);
3727 static int io_fallocate_prep(struct io_kiocb
*req
,
3728 const struct io_uring_sqe
*sqe
)
3730 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3732 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3735 req
->sync
.off
= READ_ONCE(sqe
->off
);
3736 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3737 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3741 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
3745 /* fallocate always requiring blocking context */
3748 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3751 req_set_fail_links(req
);
3752 io_req_complete(req
, ret
);
3756 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3758 const char __user
*fname
;
3761 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3763 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3766 /* open.how should be already initialised */
3767 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3768 req
->open
.how
.flags
|= O_LARGEFILE
;
3770 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3771 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3772 req
->open
.filename
= getname(fname
);
3773 if (IS_ERR(req
->open
.filename
)) {
3774 ret
= PTR_ERR(req
->open
.filename
);
3775 req
->open
.filename
= NULL
;
3778 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3779 req
->flags
|= REQ_F_NEED_CLEANUP
;
3783 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3787 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3789 mode
= READ_ONCE(sqe
->len
);
3790 flags
= READ_ONCE(sqe
->open_flags
);
3791 req
->open
.how
= build_open_how(flags
, mode
);
3792 return __io_openat_prep(req
, sqe
);
3795 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3797 struct open_how __user
*how
;
3801 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3803 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3804 len
= READ_ONCE(sqe
->len
);
3805 if (len
< OPEN_HOW_SIZE_VER0
)
3808 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3813 return __io_openat_prep(req
, sqe
);
3816 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
3818 struct open_flags op
;
3825 ret
= build_open_flags(&req
->open
.how
, &op
);
3829 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3833 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3836 ret
= PTR_ERR(file
);
3838 fsnotify_open(file
);
3839 fd_install(ret
, file
);
3842 putname(req
->open
.filename
);
3843 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3845 req_set_fail_links(req
);
3846 io_req_complete(req
, ret
);
3850 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
3852 return io_openat2(req
, force_nonblock
);
3855 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3856 const struct io_uring_sqe
*sqe
)
3858 struct io_provide_buf
*p
= &req
->pbuf
;
3861 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3864 tmp
= READ_ONCE(sqe
->fd
);
3865 if (!tmp
|| tmp
> USHRT_MAX
)
3868 memset(p
, 0, sizeof(*p
));
3870 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3874 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3875 int bgid
, unsigned nbufs
)
3879 /* shouldn't happen */
3883 /* the head kbuf is the list itself */
3884 while (!list_empty(&buf
->list
)) {
3885 struct io_buffer
*nxt
;
3887 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3888 list_del(&nxt
->list
);
3895 idr_remove(&ctx
->io_buffer_idr
, bgid
);
3900 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3901 struct io_comp_state
*cs
)
3903 struct io_provide_buf
*p
= &req
->pbuf
;
3904 struct io_ring_ctx
*ctx
= req
->ctx
;
3905 struct io_buffer
*head
;
3908 io_ring_submit_lock(ctx
, !force_nonblock
);
3910 lockdep_assert_held(&ctx
->uring_lock
);
3913 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3915 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3917 io_ring_submit_lock(ctx
, !force_nonblock
);
3919 req_set_fail_links(req
);
3920 __io_req_complete(req
, ret
, 0, cs
);
3924 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3925 const struct io_uring_sqe
*sqe
)
3927 struct io_provide_buf
*p
= &req
->pbuf
;
3930 if (sqe
->ioprio
|| sqe
->rw_flags
)
3933 tmp
= READ_ONCE(sqe
->fd
);
3934 if (!tmp
|| tmp
> USHRT_MAX
)
3937 p
->addr
= READ_ONCE(sqe
->addr
);
3938 p
->len
= READ_ONCE(sqe
->len
);
3940 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
3943 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3944 tmp
= READ_ONCE(sqe
->off
);
3945 if (tmp
> USHRT_MAX
)
3951 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3953 struct io_buffer
*buf
;
3954 u64 addr
= pbuf
->addr
;
3955 int i
, bid
= pbuf
->bid
;
3957 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3958 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3963 buf
->len
= pbuf
->len
;
3968 INIT_LIST_HEAD(&buf
->list
);
3971 list_add_tail(&buf
->list
, &(*head
)->list
);
3975 return i
? i
: -ENOMEM
;
3978 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3979 struct io_comp_state
*cs
)
3981 struct io_provide_buf
*p
= &req
->pbuf
;
3982 struct io_ring_ctx
*ctx
= req
->ctx
;
3983 struct io_buffer
*head
, *list
;
3986 io_ring_submit_lock(ctx
, !force_nonblock
);
3988 lockdep_assert_held(&ctx
->uring_lock
);
3990 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3992 ret
= io_add_buffers(p
, &head
);
3997 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
4000 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
4005 io_ring_submit_unlock(ctx
, !force_nonblock
);
4007 req_set_fail_links(req
);
4008 __io_req_complete(req
, ret
, 0, cs
);
4012 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
4013 const struct io_uring_sqe
*sqe
)
4015 #if defined(CONFIG_EPOLL)
4016 if (sqe
->ioprio
|| sqe
->buf_index
)
4018 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4021 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
4022 req
->epoll
.op
= READ_ONCE(sqe
->len
);
4023 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
4025 if (ep_op_has_event(req
->epoll
.op
)) {
4026 struct epoll_event __user
*ev
;
4028 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4029 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
4039 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
,
4040 struct io_comp_state
*cs
)
4042 #if defined(CONFIG_EPOLL)
4043 struct io_epoll
*ie
= &req
->epoll
;
4046 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
4047 if (force_nonblock
&& ret
== -EAGAIN
)
4051 req_set_fail_links(req
);
4052 __io_req_complete(req
, ret
, 0, cs
);
4059 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4061 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4062 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
4064 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4067 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
4068 req
->madvise
.len
= READ_ONCE(sqe
->len
);
4069 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4076 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
4078 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4079 struct io_madvise
*ma
= &req
->madvise
;
4085 ret
= do_madvise(current
->mm
, ma
->addr
, ma
->len
, ma
->advice
);
4087 req_set_fail_links(req
);
4088 io_req_complete(req
, ret
);
4095 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4097 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
4099 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4102 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
4103 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
4104 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
4108 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
4110 struct io_fadvise
*fa
= &req
->fadvise
;
4113 if (force_nonblock
) {
4114 switch (fa
->advice
) {
4115 case POSIX_FADV_NORMAL
:
4116 case POSIX_FADV_RANDOM
:
4117 case POSIX_FADV_SEQUENTIAL
:
4124 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
4126 req_set_fail_links(req
);
4127 io_req_complete(req
, ret
);
4131 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4133 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
)))
4135 if (sqe
->ioprio
|| sqe
->buf_index
)
4137 if (req
->flags
& REQ_F_FIXED_FILE
)
4140 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
4141 req
->statx
.mask
= READ_ONCE(sqe
->len
);
4142 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4143 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4144 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
4149 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
4151 struct io_statx
*ctx
= &req
->statx
;
4154 if (force_nonblock
) {
4155 /* only need file table for an actual valid fd */
4156 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
4157 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4161 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
4165 req_set_fail_links(req
);
4166 io_req_complete(req
, ret
);
4170 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4173 * If we queue this for async, it must not be cancellable. That would
4174 * leave the 'file' in an undeterminate state, and here need to modify
4175 * io_wq_work.flags, so initialize io_wq_work firstly.
4177 io_req_init_async(req
);
4178 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
4180 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4182 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
4183 sqe
->rw_flags
|| sqe
->buf_index
)
4185 if (req
->flags
& REQ_F_FIXED_FILE
)
4188 req
->close
.fd
= READ_ONCE(sqe
->fd
);
4189 if ((req
->file
&& req
->file
->f_op
== &io_uring_fops
))
4192 req
->close
.put_file
= NULL
;
4196 static int io_close(struct io_kiocb
*req
, bool force_nonblock
,
4197 struct io_comp_state
*cs
)
4199 struct io_close
*close
= &req
->close
;
4202 /* might be already done during nonblock submission */
4203 if (!close
->put_file
) {
4204 ret
= __close_fd_get_file(close
->fd
, &close
->put_file
);
4206 return (ret
== -ENOENT
) ? -EBADF
: ret
;
4209 /* if the file has a flush method, be safe and punt to async */
4210 if (close
->put_file
->f_op
->flush
&& force_nonblock
) {
4211 /* was never set, but play safe */
4212 req
->flags
&= ~REQ_F_NOWAIT
;
4213 /* avoid grabbing files - we don't need the files */
4214 req
->flags
|= REQ_F_NO_FILE_TABLE
;
4218 /* No ->flush() or already async, safely close from here */
4219 ret
= filp_close(close
->put_file
, req
->work
.identity
->files
);
4221 req_set_fail_links(req
);
4222 fput(close
->put_file
);
4223 close
->put_file
= NULL
;
4224 __io_req_complete(req
, ret
, 0, cs
);
4228 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4230 struct io_ring_ctx
*ctx
= req
->ctx
;
4235 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
4237 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
4240 req
->sync
.off
= READ_ONCE(sqe
->off
);
4241 req
->sync
.len
= READ_ONCE(sqe
->len
);
4242 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
4246 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
4250 /* sync_file_range always requires a blocking context */
4254 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
4257 req_set_fail_links(req
);
4258 io_req_complete(req
, ret
);
4262 #if defined(CONFIG_NET)
4263 static int io_setup_async_msg(struct io_kiocb
*req
,
4264 struct io_async_msghdr
*kmsg
)
4266 struct io_async_msghdr
*async_msg
= req
->async_data
;
4270 if (io_alloc_async_data(req
)) {
4271 if (kmsg
->iov
!= kmsg
->fast_iov
)
4275 async_msg
= req
->async_data
;
4276 req
->flags
|= REQ_F_NEED_CLEANUP
;
4277 memcpy(async_msg
, kmsg
, sizeof(*kmsg
));
4281 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4282 struct io_async_msghdr
*iomsg
)
4284 iomsg
->iov
= iomsg
->fast_iov
;
4285 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4286 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4287 req
->sr_msg
.msg_flags
, &iomsg
->iov
);
4290 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4292 struct io_async_msghdr
*async_msg
= req
->async_data
;
4293 struct io_sr_msg
*sr
= &req
->sr_msg
;
4296 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4299 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4300 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4301 sr
->len
= READ_ONCE(sqe
->len
);
4303 #ifdef CONFIG_COMPAT
4304 if (req
->ctx
->compat
)
4305 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4308 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4310 ret
= io_sendmsg_copy_hdr(req
, async_msg
);
4312 req
->flags
|= REQ_F_NEED_CLEANUP
;
4316 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4317 struct io_comp_state
*cs
)
4319 struct io_async_msghdr iomsg
, *kmsg
;
4320 struct socket
*sock
;
4324 sock
= sock_from_file(req
->file
, &ret
);
4325 if (unlikely(!sock
))
4328 if (req
->async_data
) {
4329 kmsg
= req
->async_data
;
4330 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4331 /* if iov is set, it's allocated already */
4333 kmsg
->iov
= kmsg
->fast_iov
;
4334 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4336 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4342 flags
= req
->sr_msg
.msg_flags
;
4343 if (flags
& MSG_DONTWAIT
)
4344 req
->flags
|= REQ_F_NOWAIT
;
4345 else if (force_nonblock
)
4346 flags
|= MSG_DONTWAIT
;
4348 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4349 if (force_nonblock
&& ret
== -EAGAIN
)
4350 return io_setup_async_msg(req
, kmsg
);
4351 if (ret
== -ERESTARTSYS
)
4354 if (kmsg
->iov
!= kmsg
->fast_iov
)
4356 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4358 req_set_fail_links(req
);
4359 __io_req_complete(req
, ret
, 0, cs
);
4363 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4364 struct io_comp_state
*cs
)
4366 struct io_sr_msg
*sr
= &req
->sr_msg
;
4369 struct socket
*sock
;
4373 sock
= sock_from_file(req
->file
, &ret
);
4374 if (unlikely(!sock
))
4377 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4381 msg
.msg_name
= NULL
;
4382 msg
.msg_control
= NULL
;
4383 msg
.msg_controllen
= 0;
4384 msg
.msg_namelen
= 0;
4386 flags
= req
->sr_msg
.msg_flags
;
4387 if (flags
& MSG_DONTWAIT
)
4388 req
->flags
|= REQ_F_NOWAIT
;
4389 else if (force_nonblock
)
4390 flags
|= MSG_DONTWAIT
;
4392 msg
.msg_flags
= flags
;
4393 ret
= sock_sendmsg(sock
, &msg
);
4394 if (force_nonblock
&& ret
== -EAGAIN
)
4396 if (ret
== -ERESTARTSYS
)
4400 req_set_fail_links(req
);
4401 __io_req_complete(req
, ret
, 0, cs
);
4405 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4406 struct io_async_msghdr
*iomsg
)
4408 struct io_sr_msg
*sr
= &req
->sr_msg
;
4409 struct iovec __user
*uiov
;
4413 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4414 &iomsg
->uaddr
, &uiov
, &iov_len
);
4418 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4421 if (copy_from_user(iomsg
->iov
, uiov
, sizeof(*uiov
)))
4423 sr
->len
= iomsg
->iov
[0].iov_len
;
4424 iov_iter_init(&iomsg
->msg
.msg_iter
, READ
, iomsg
->iov
, 1,
4428 ret
= __import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4429 &iomsg
->iov
, &iomsg
->msg
.msg_iter
,
4438 #ifdef CONFIG_COMPAT
4439 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4440 struct io_async_msghdr
*iomsg
)
4442 struct compat_msghdr __user
*msg_compat
;
4443 struct io_sr_msg
*sr
= &req
->sr_msg
;
4444 struct compat_iovec __user
*uiov
;
4449 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4450 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4455 uiov
= compat_ptr(ptr
);
4456 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4457 compat_ssize_t clen
;
4461 if (!access_ok(uiov
, sizeof(*uiov
)))
4463 if (__get_user(clen
, &uiov
->iov_len
))
4467 sr
->len
= iomsg
->iov
[0].iov_len
;
4470 ret
= __import_iovec(READ
, (struct iovec __user
*)uiov
, len
,
4471 UIO_FASTIOV
, &iomsg
->iov
,
4472 &iomsg
->msg
.msg_iter
, true);
4481 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4482 struct io_async_msghdr
*iomsg
)
4484 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4485 iomsg
->iov
= iomsg
->fast_iov
;
4487 #ifdef CONFIG_COMPAT
4488 if (req
->ctx
->compat
)
4489 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4492 return __io_recvmsg_copy_hdr(req
, iomsg
);
4495 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4498 struct io_sr_msg
*sr
= &req
->sr_msg
;
4499 struct io_buffer
*kbuf
;
4501 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4506 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4510 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4512 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4515 static int io_recvmsg_prep(struct io_kiocb
*req
,
4516 const struct io_uring_sqe
*sqe
)
4518 struct io_async_msghdr
*async_msg
= req
->async_data
;
4519 struct io_sr_msg
*sr
= &req
->sr_msg
;
4522 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4525 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4526 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4527 sr
->len
= READ_ONCE(sqe
->len
);
4528 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4530 #ifdef CONFIG_COMPAT
4531 if (req
->ctx
->compat
)
4532 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4535 if (!async_msg
|| !io_op_defs
[req
->opcode
].needs_async_data
)
4537 ret
= io_recvmsg_copy_hdr(req
, async_msg
);
4539 req
->flags
|= REQ_F_NEED_CLEANUP
;
4543 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4544 struct io_comp_state
*cs
)
4546 struct io_async_msghdr iomsg
, *kmsg
;
4547 struct socket
*sock
;
4548 struct io_buffer
*kbuf
;
4550 int ret
, cflags
= 0;
4552 sock
= sock_from_file(req
->file
, &ret
);
4553 if (unlikely(!sock
))
4556 if (req
->async_data
) {
4557 kmsg
= req
->async_data
;
4558 kmsg
->msg
.msg_name
= &kmsg
->addr
;
4559 /* if iov is set, it's allocated already */
4561 kmsg
->iov
= kmsg
->fast_iov
;
4562 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4564 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4570 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4571 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4573 return PTR_ERR(kbuf
);
4574 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4575 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
4576 1, req
->sr_msg
.len
);
4579 flags
= req
->sr_msg
.msg_flags
;
4580 if (flags
& MSG_DONTWAIT
)
4581 req
->flags
|= REQ_F_NOWAIT
;
4582 else if (force_nonblock
)
4583 flags
|= MSG_DONTWAIT
;
4585 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4586 kmsg
->uaddr
, flags
);
4587 if (force_nonblock
&& ret
== -EAGAIN
)
4588 return io_setup_async_msg(req
, kmsg
);
4589 if (ret
== -ERESTARTSYS
)
4592 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4593 cflags
= io_put_recv_kbuf(req
);
4594 if (kmsg
->iov
!= kmsg
->fast_iov
)
4596 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4598 req_set_fail_links(req
);
4599 __io_req_complete(req
, ret
, cflags
, cs
);
4603 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4604 struct io_comp_state
*cs
)
4606 struct io_buffer
*kbuf
;
4607 struct io_sr_msg
*sr
= &req
->sr_msg
;
4609 void __user
*buf
= sr
->buf
;
4610 struct socket
*sock
;
4613 int ret
, cflags
= 0;
4615 sock
= sock_from_file(req
->file
, &ret
);
4616 if (unlikely(!sock
))
4619 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4620 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4622 return PTR_ERR(kbuf
);
4623 buf
= u64_to_user_ptr(kbuf
->addr
);
4626 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4630 msg
.msg_name
= NULL
;
4631 msg
.msg_control
= NULL
;
4632 msg
.msg_controllen
= 0;
4633 msg
.msg_namelen
= 0;
4634 msg
.msg_iocb
= NULL
;
4637 flags
= req
->sr_msg
.msg_flags
;
4638 if (flags
& MSG_DONTWAIT
)
4639 req
->flags
|= REQ_F_NOWAIT
;
4640 else if (force_nonblock
)
4641 flags
|= MSG_DONTWAIT
;
4643 ret
= sock_recvmsg(sock
, &msg
, flags
);
4644 if (force_nonblock
&& ret
== -EAGAIN
)
4646 if (ret
== -ERESTARTSYS
)
4649 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4650 cflags
= io_put_recv_kbuf(req
);
4652 req_set_fail_links(req
);
4653 __io_req_complete(req
, ret
, cflags
, cs
);
4657 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4659 struct io_accept
*accept
= &req
->accept
;
4661 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4663 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4666 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4667 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4668 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4669 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4673 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4674 struct io_comp_state
*cs
)
4676 struct io_accept
*accept
= &req
->accept
;
4677 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4680 if (req
->file
->f_flags
& O_NONBLOCK
)
4681 req
->flags
|= REQ_F_NOWAIT
;
4683 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4684 accept
->addr_len
, accept
->flags
,
4686 if (ret
== -EAGAIN
&& force_nonblock
)
4689 if (ret
== -ERESTARTSYS
)
4691 req_set_fail_links(req
);
4693 __io_req_complete(req
, ret
, 0, cs
);
4697 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4699 struct io_connect
*conn
= &req
->connect
;
4700 struct io_async_connect
*io
= req
->async_data
;
4702 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4704 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4707 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4708 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4713 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4717 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4718 struct io_comp_state
*cs
)
4720 struct io_async_connect __io
, *io
;
4721 unsigned file_flags
;
4724 if (req
->async_data
) {
4725 io
= req
->async_data
;
4727 ret
= move_addr_to_kernel(req
->connect
.addr
,
4728 req
->connect
.addr_len
,
4735 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4737 ret
= __sys_connect_file(req
->file
, &io
->address
,
4738 req
->connect
.addr_len
, file_flags
);
4739 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4740 if (req
->async_data
)
4742 if (io_alloc_async_data(req
)) {
4746 io
= req
->async_data
;
4747 memcpy(req
->async_data
, &__io
, sizeof(__io
));
4750 if (ret
== -ERESTARTSYS
)
4754 req_set_fail_links(req
);
4755 __io_req_complete(req
, ret
, 0, cs
);
4758 #else /* !CONFIG_NET */
4759 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4764 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4765 struct io_comp_state
*cs
)
4770 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4771 struct io_comp_state
*cs
)
4776 static int io_recvmsg_prep(struct io_kiocb
*req
,
4777 const struct io_uring_sqe
*sqe
)
4782 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4783 struct io_comp_state
*cs
)
4788 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4789 struct io_comp_state
*cs
)
4794 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4799 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4800 struct io_comp_state
*cs
)
4805 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4810 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4811 struct io_comp_state
*cs
)
4815 #endif /* CONFIG_NET */
4817 struct io_poll_table
{
4818 struct poll_table_struct pt
;
4819 struct io_kiocb
*req
;
4823 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4824 __poll_t mask
, task_work_func_t func
)
4829 /* for instances that support it check for an event match first: */
4830 if (mask
&& !(mask
& poll
->events
))
4833 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4835 list_del_init(&poll
->wait
.entry
);
4838 init_task_work(&req
->task_work
, func
);
4839 percpu_ref_get(&req
->ctx
->refs
);
4842 * If we using the signalfd wait_queue_head for this wakeup, then
4843 * it's not safe to use TWA_SIGNAL as we could be recursing on the
4844 * tsk->sighand->siglock on doing the wakeup. Should not be needed
4845 * either, as the normal wakeup will suffice.
4847 twa_signal_ok
= (poll
->head
!= &req
->task
->sighand
->signalfd_wqh
);
4850 * If this fails, then the task is exiting. When a task exits, the
4851 * work gets canceled, so just cancel this request as well instead
4852 * of executing it. We can't safely execute it anyway, as we may not
4853 * have the needed state needed for it anyway.
4855 ret
= io_req_task_work_add(req
, twa_signal_ok
);
4856 if (unlikely(ret
)) {
4857 struct task_struct
*tsk
;
4859 WRITE_ONCE(poll
->canceled
, true);
4860 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
4861 task_work_add(tsk
, &req
->task_work
, TWA_NONE
);
4862 wake_up_process(tsk
);
4867 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4868 __acquires(&req
->ctx
->completion_lock
)
4870 struct io_ring_ctx
*ctx
= req
->ctx
;
4872 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4873 struct poll_table_struct pt
= { ._key
= poll
->events
};
4875 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4878 spin_lock_irq(&ctx
->completion_lock
);
4879 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4880 add_wait_queue(poll
->head
, &poll
->wait
);
4887 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
4889 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
4890 if (req
->opcode
== IORING_OP_POLL_ADD
)
4891 return req
->async_data
;
4892 return req
->apoll
->double_poll
;
4895 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
4897 if (req
->opcode
== IORING_OP_POLL_ADD
)
4899 return &req
->apoll
->poll
;
4902 static void io_poll_remove_double(struct io_kiocb
*req
)
4904 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
4906 lockdep_assert_held(&req
->ctx
->completion_lock
);
4908 if (poll
&& poll
->head
) {
4909 struct wait_queue_head
*head
= poll
->head
;
4911 spin_lock(&head
->lock
);
4912 list_del_init(&poll
->wait
.entry
);
4913 if (poll
->wait
.private)
4914 refcount_dec(&req
->refs
);
4916 spin_unlock(&head
->lock
);
4920 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4922 struct io_ring_ctx
*ctx
= req
->ctx
;
4924 io_poll_remove_double(req
);
4925 req
->poll
.done
= true;
4926 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
4927 io_commit_cqring(ctx
);
4930 static void io_poll_task_handler(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
4932 struct io_ring_ctx
*ctx
= req
->ctx
;
4934 if (io_poll_rewait(req
, &req
->poll
)) {
4935 spin_unlock_irq(&ctx
->completion_lock
);
4939 hash_del(&req
->hash_node
);
4940 io_poll_complete(req
, req
->result
, 0);
4941 spin_unlock_irq(&ctx
->completion_lock
);
4943 *nxt
= io_put_req_find_next(req
);
4944 io_cqring_ev_posted(ctx
);
4947 static void io_poll_task_func(struct callback_head
*cb
)
4949 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4950 struct io_ring_ctx
*ctx
= req
->ctx
;
4951 struct io_kiocb
*nxt
= NULL
;
4953 io_poll_task_handler(req
, &nxt
);
4955 __io_req_task_submit(nxt
);
4956 percpu_ref_put(&ctx
->refs
);
4959 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4960 int sync
, void *key
)
4962 struct io_kiocb
*req
= wait
->private;
4963 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
4964 __poll_t mask
= key_to_poll(key
);
4966 /* for instances that support it check for an event match first: */
4967 if (mask
&& !(mask
& poll
->events
))
4970 list_del_init(&wait
->entry
);
4972 if (poll
&& poll
->head
) {
4975 spin_lock(&poll
->head
->lock
);
4976 done
= list_empty(&poll
->wait
.entry
);
4978 list_del_init(&poll
->wait
.entry
);
4979 /* make sure double remove sees this as being gone */
4980 wait
->private = NULL
;
4981 spin_unlock(&poll
->head
->lock
);
4983 __io_async_wake(req
, poll
, mask
, io_poll_task_func
);
4985 refcount_dec(&req
->refs
);
4989 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
4990 wait_queue_func_t wake_func
)
4994 poll
->canceled
= false;
4995 poll
->events
= events
;
4996 INIT_LIST_HEAD(&poll
->wait
.entry
);
4997 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
5000 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
5001 struct wait_queue_head
*head
,
5002 struct io_poll_iocb
**poll_ptr
)
5004 struct io_kiocb
*req
= pt
->req
;
5007 * If poll->head is already set, it's because the file being polled
5008 * uses multiple waitqueues for poll handling (eg one for read, one
5009 * for write). Setup a separate io_poll_iocb if this happens.
5011 if (unlikely(poll
->head
)) {
5012 struct io_poll_iocb
*poll_one
= poll
;
5014 /* already have a 2nd entry, fail a third attempt */
5016 pt
->error
= -EINVAL
;
5019 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
5021 pt
->error
= -ENOMEM
;
5024 io_init_poll_iocb(poll
, poll_one
->events
, io_poll_double_wake
);
5025 refcount_inc(&req
->refs
);
5026 poll
->wait
.private = req
;
5033 if (poll
->events
& EPOLLEXCLUSIVE
)
5034 add_wait_queue_exclusive(head
, &poll
->wait
);
5036 add_wait_queue(head
, &poll
->wait
);
5039 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5040 struct poll_table_struct
*p
)
5042 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5043 struct async_poll
*apoll
= pt
->req
->apoll
;
5045 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
5048 static void io_async_task_func(struct callback_head
*cb
)
5050 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
5051 struct async_poll
*apoll
= req
->apoll
;
5052 struct io_ring_ctx
*ctx
= req
->ctx
;
5054 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
5056 if (io_poll_rewait(req
, &apoll
->poll
)) {
5057 spin_unlock_irq(&ctx
->completion_lock
);
5058 percpu_ref_put(&ctx
->refs
);
5062 /* If req is still hashed, it cannot have been canceled. Don't check. */
5063 if (hash_hashed(&req
->hash_node
))
5064 hash_del(&req
->hash_node
);
5066 io_poll_remove_double(req
);
5067 spin_unlock_irq(&ctx
->completion_lock
);
5069 if (!READ_ONCE(apoll
->poll
.canceled
))
5070 __io_req_task_submit(req
);
5072 __io_req_task_cancel(req
, -ECANCELED
);
5074 percpu_ref_put(&ctx
->refs
);
5075 kfree(apoll
->double_poll
);
5079 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5082 struct io_kiocb
*req
= wait
->private;
5083 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
5085 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
5088 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
5091 static void io_poll_req_insert(struct io_kiocb
*req
)
5093 struct io_ring_ctx
*ctx
= req
->ctx
;
5094 struct hlist_head
*list
;
5096 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
5097 hlist_add_head(&req
->hash_node
, list
);
5100 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
5101 struct io_poll_iocb
*poll
,
5102 struct io_poll_table
*ipt
, __poll_t mask
,
5103 wait_queue_func_t wake_func
)
5104 __acquires(&ctx
->completion_lock
)
5106 struct io_ring_ctx
*ctx
= req
->ctx
;
5107 bool cancel
= false;
5109 io_init_poll_iocb(poll
, mask
, wake_func
);
5110 poll
->file
= req
->file
;
5111 poll
->wait
.private = req
;
5113 ipt
->pt
._key
= mask
;
5115 ipt
->error
= -EINVAL
;
5117 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
5119 spin_lock_irq(&ctx
->completion_lock
);
5120 if (likely(poll
->head
)) {
5121 spin_lock(&poll
->head
->lock
);
5122 if (unlikely(list_empty(&poll
->wait
.entry
))) {
5128 if (mask
|| ipt
->error
)
5129 list_del_init(&poll
->wait
.entry
);
5131 WRITE_ONCE(poll
->canceled
, true);
5132 else if (!poll
->done
) /* actually waiting for an event */
5133 io_poll_req_insert(req
);
5134 spin_unlock(&poll
->head
->lock
);
5140 static bool io_arm_poll_handler(struct io_kiocb
*req
)
5142 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
5143 struct io_ring_ctx
*ctx
= req
->ctx
;
5144 struct async_poll
*apoll
;
5145 struct io_poll_table ipt
;
5149 if (!req
->file
|| !file_can_poll(req
->file
))
5151 if (req
->flags
& REQ_F_POLLED
)
5155 else if (def
->pollout
)
5159 /* if we can't nonblock try, then no point in arming a poll handler */
5160 if (!io_file_supports_async(req
->file
, rw
))
5163 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
5164 if (unlikely(!apoll
))
5166 apoll
->double_poll
= NULL
;
5168 req
->flags
|= REQ_F_POLLED
;
5170 INIT_HLIST_NODE(&req
->hash_node
);
5174 mask
|= POLLIN
| POLLRDNORM
;
5176 mask
|= POLLOUT
| POLLWRNORM
;
5178 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5179 if ((req
->opcode
== IORING_OP_RECVMSG
) &&
5180 (req
->sr_msg
.msg_flags
& MSG_ERRQUEUE
))
5183 mask
|= POLLERR
| POLLPRI
;
5185 ipt
.pt
._qproc
= io_async_queue_proc
;
5187 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
5189 if (ret
|| ipt
.error
) {
5190 io_poll_remove_double(req
);
5191 spin_unlock_irq(&ctx
->completion_lock
);
5192 kfree(apoll
->double_poll
);
5196 spin_unlock_irq(&ctx
->completion_lock
);
5197 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
5198 apoll
->poll
.events
);
5202 static bool __io_poll_remove_one(struct io_kiocb
*req
,
5203 struct io_poll_iocb
*poll
)
5205 bool do_complete
= false;
5207 spin_lock(&poll
->head
->lock
);
5208 WRITE_ONCE(poll
->canceled
, true);
5209 if (!list_empty(&poll
->wait
.entry
)) {
5210 list_del_init(&poll
->wait
.entry
);
5213 spin_unlock(&poll
->head
->lock
);
5214 hash_del(&req
->hash_node
);
5218 static bool io_poll_remove_one(struct io_kiocb
*req
)
5222 io_poll_remove_double(req
);
5224 if (req
->opcode
== IORING_OP_POLL_ADD
) {
5225 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
5227 struct async_poll
*apoll
= req
->apoll
;
5229 /* non-poll requests have submit ref still */
5230 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
5233 kfree(apoll
->double_poll
);
5239 io_cqring_fill_event(req
, -ECANCELED
);
5240 io_commit_cqring(req
->ctx
);
5241 req_set_fail_links(req
);
5242 io_put_req_deferred(req
, 1);
5249 * Returns true if we found and killed one or more poll requests
5251 static bool io_poll_remove_all(struct io_ring_ctx
*ctx
, struct task_struct
*tsk
)
5253 struct hlist_node
*tmp
;
5254 struct io_kiocb
*req
;
5257 spin_lock_irq(&ctx
->completion_lock
);
5258 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
5259 struct hlist_head
*list
;
5261 list
= &ctx
->cancel_hash
[i
];
5262 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
) {
5263 if (io_task_match(req
, tsk
))
5264 posted
+= io_poll_remove_one(req
);
5267 spin_unlock_irq(&ctx
->completion_lock
);
5270 io_cqring_ev_posted(ctx
);
5275 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
5277 struct hlist_head
*list
;
5278 struct io_kiocb
*req
;
5280 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
5281 hlist_for_each_entry(req
, list
, hash_node
) {
5282 if (sqe_addr
!= req
->user_data
)
5284 if (io_poll_remove_one(req
))
5292 static int io_poll_remove_prep(struct io_kiocb
*req
,
5293 const struct io_uring_sqe
*sqe
)
5295 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5297 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5301 req
->poll
.addr
= READ_ONCE(sqe
->addr
);
5306 * Find a running poll command that matches one specified in sqe->addr,
5307 * and remove it if found.
5309 static int io_poll_remove(struct io_kiocb
*req
)
5311 struct io_ring_ctx
*ctx
= req
->ctx
;
5315 addr
= req
->poll
.addr
;
5316 spin_lock_irq(&ctx
->completion_lock
);
5317 ret
= io_poll_cancel(ctx
, addr
);
5318 spin_unlock_irq(&ctx
->completion_lock
);
5321 req_set_fail_links(req
);
5322 io_req_complete(req
, ret
);
5326 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5329 struct io_kiocb
*req
= wait
->private;
5330 struct io_poll_iocb
*poll
= &req
->poll
;
5332 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5335 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5336 struct poll_table_struct
*p
)
5338 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5340 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->async_data
);
5343 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5345 struct io_poll_iocb
*poll
= &req
->poll
;
5348 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5350 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
5355 events
= READ_ONCE(sqe
->poll32_events
);
5357 events
= swahw32(events
);
5359 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
5360 (events
& EPOLLEXCLUSIVE
);
5364 static int io_poll_add(struct io_kiocb
*req
)
5366 struct io_poll_iocb
*poll
= &req
->poll
;
5367 struct io_ring_ctx
*ctx
= req
->ctx
;
5368 struct io_poll_table ipt
;
5371 INIT_HLIST_NODE(&req
->hash_node
);
5372 ipt
.pt
._qproc
= io_poll_queue_proc
;
5374 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5377 if (mask
) { /* no async, we'd stolen it */
5379 io_poll_complete(req
, mask
, 0);
5381 spin_unlock_irq(&ctx
->completion_lock
);
5384 io_cqring_ev_posted(ctx
);
5390 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5392 struct io_timeout_data
*data
= container_of(timer
,
5393 struct io_timeout_data
, timer
);
5394 struct io_kiocb
*req
= data
->req
;
5395 struct io_ring_ctx
*ctx
= req
->ctx
;
5396 unsigned long flags
;
5398 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5399 list_del_init(&req
->timeout
.list
);
5400 atomic_set(&req
->ctx
->cq_timeouts
,
5401 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5403 io_cqring_fill_event(req
, -ETIME
);
5404 io_commit_cqring(ctx
);
5405 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5407 io_cqring_ev_posted(ctx
);
5408 req_set_fail_links(req
);
5410 return HRTIMER_NORESTART
;
5413 static int __io_timeout_cancel(struct io_kiocb
*req
)
5415 struct io_timeout_data
*io
= req
->async_data
;
5418 ret
= hrtimer_try_to_cancel(&io
->timer
);
5421 list_del_init(&req
->timeout
.list
);
5423 req_set_fail_links(req
);
5424 io_cqring_fill_event(req
, -ECANCELED
);
5425 io_put_req_deferred(req
, 1);
5429 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5431 struct io_kiocb
*req
;
5434 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5435 if (user_data
== req
->user_data
) {
5444 return __io_timeout_cancel(req
);
5447 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5448 const struct io_uring_sqe
*sqe
)
5450 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5452 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5454 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
|| sqe
->timeout_flags
)
5457 req
->timeout_rem
.addr
= READ_ONCE(sqe
->addr
);
5462 * Remove or update an existing timeout command
5464 static int io_timeout_remove(struct io_kiocb
*req
)
5466 struct io_ring_ctx
*ctx
= req
->ctx
;
5469 spin_lock_irq(&ctx
->completion_lock
);
5470 ret
= io_timeout_cancel(ctx
, req
->timeout_rem
.addr
);
5472 io_cqring_fill_event(req
, ret
);
5473 io_commit_cqring(ctx
);
5474 spin_unlock_irq(&ctx
->completion_lock
);
5475 io_cqring_ev_posted(ctx
);
5477 req_set_fail_links(req
);
5482 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5483 bool is_timeout_link
)
5485 struct io_timeout_data
*data
;
5487 u32 off
= READ_ONCE(sqe
->off
);
5489 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5491 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5493 if (off
&& is_timeout_link
)
5495 flags
= READ_ONCE(sqe
->timeout_flags
);
5496 if (flags
& ~IORING_TIMEOUT_ABS
)
5499 req
->timeout
.off
= off
;
5501 if (!req
->async_data
&& io_alloc_async_data(req
))
5504 data
= req
->async_data
;
5507 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5510 if (flags
& IORING_TIMEOUT_ABS
)
5511 data
->mode
= HRTIMER_MODE_ABS
;
5513 data
->mode
= HRTIMER_MODE_REL
;
5515 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5519 static int io_timeout(struct io_kiocb
*req
)
5521 struct io_ring_ctx
*ctx
= req
->ctx
;
5522 struct io_timeout_data
*data
= req
->async_data
;
5523 struct list_head
*entry
;
5524 u32 tail
, off
= req
->timeout
.off
;
5526 spin_lock_irq(&ctx
->completion_lock
);
5529 * sqe->off holds how many events that need to occur for this
5530 * timeout event to be satisfied. If it isn't set, then this is
5531 * a pure timeout request, sequence isn't used.
5533 if (io_is_timeout_noseq(req
)) {
5534 entry
= ctx
->timeout_list
.prev
;
5538 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5539 req
->timeout
.target_seq
= tail
+ off
;
5542 * Insertion sort, ensuring the first entry in the list is always
5543 * the one we need first.
5545 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5546 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5549 if (io_is_timeout_noseq(nxt
))
5551 /* nxt.seq is behind @tail, otherwise would've been completed */
5552 if (off
>= nxt
->timeout
.target_seq
- tail
)
5556 list_add(&req
->timeout
.list
, entry
);
5557 data
->timer
.function
= io_timeout_fn
;
5558 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5559 spin_unlock_irq(&ctx
->completion_lock
);
5563 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5565 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5567 return req
->user_data
== (unsigned long) data
;
5570 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5572 enum io_wq_cancel cancel_ret
;
5575 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5576 switch (cancel_ret
) {
5577 case IO_WQ_CANCEL_OK
:
5580 case IO_WQ_CANCEL_RUNNING
:
5583 case IO_WQ_CANCEL_NOTFOUND
:
5591 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5592 struct io_kiocb
*req
, __u64 sqe_addr
,
5595 unsigned long flags
;
5598 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5599 if (ret
!= -ENOENT
) {
5600 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5604 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5605 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5608 ret
= io_poll_cancel(ctx
, sqe_addr
);
5612 io_cqring_fill_event(req
, ret
);
5613 io_commit_cqring(ctx
);
5614 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5615 io_cqring_ev_posted(ctx
);
5618 req_set_fail_links(req
);
5622 static int io_async_cancel_prep(struct io_kiocb
*req
,
5623 const struct io_uring_sqe
*sqe
)
5625 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5627 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5629 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5632 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5636 static int io_async_cancel(struct io_kiocb
*req
)
5638 struct io_ring_ctx
*ctx
= req
->ctx
;
5640 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
5644 static int io_files_update_prep(struct io_kiocb
*req
,
5645 const struct io_uring_sqe
*sqe
)
5647 if (unlikely(req
->ctx
->flags
& IORING_SETUP_SQPOLL
))
5649 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5651 if (sqe
->ioprio
|| sqe
->rw_flags
)
5654 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
5655 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
5656 if (!req
->files_update
.nr_args
)
5658 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
5662 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
,
5663 struct io_comp_state
*cs
)
5665 struct io_ring_ctx
*ctx
= req
->ctx
;
5666 struct io_uring_files_update up
;
5672 up
.offset
= req
->files_update
.offset
;
5673 up
.fds
= req
->files_update
.arg
;
5675 mutex_lock(&ctx
->uring_lock
);
5676 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
5677 mutex_unlock(&ctx
->uring_lock
);
5680 req_set_fail_links(req
);
5681 __io_req_complete(req
, ret
, 0, cs
);
5685 static int io_req_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5687 switch (req
->opcode
) {
5690 case IORING_OP_READV
:
5691 case IORING_OP_READ_FIXED
:
5692 case IORING_OP_READ
:
5693 return io_read_prep(req
, sqe
);
5694 case IORING_OP_WRITEV
:
5695 case IORING_OP_WRITE_FIXED
:
5696 case IORING_OP_WRITE
:
5697 return io_write_prep(req
, sqe
);
5698 case IORING_OP_POLL_ADD
:
5699 return io_poll_add_prep(req
, sqe
);
5700 case IORING_OP_POLL_REMOVE
:
5701 return io_poll_remove_prep(req
, sqe
);
5702 case IORING_OP_FSYNC
:
5703 return io_prep_fsync(req
, sqe
);
5704 case IORING_OP_SYNC_FILE_RANGE
:
5705 return io_prep_sfr(req
, sqe
);
5706 case IORING_OP_SENDMSG
:
5707 case IORING_OP_SEND
:
5708 return io_sendmsg_prep(req
, sqe
);
5709 case IORING_OP_RECVMSG
:
5710 case IORING_OP_RECV
:
5711 return io_recvmsg_prep(req
, sqe
);
5712 case IORING_OP_CONNECT
:
5713 return io_connect_prep(req
, sqe
);
5714 case IORING_OP_TIMEOUT
:
5715 return io_timeout_prep(req
, sqe
, false);
5716 case IORING_OP_TIMEOUT_REMOVE
:
5717 return io_timeout_remove_prep(req
, sqe
);
5718 case IORING_OP_ASYNC_CANCEL
:
5719 return io_async_cancel_prep(req
, sqe
);
5720 case IORING_OP_LINK_TIMEOUT
:
5721 return io_timeout_prep(req
, sqe
, true);
5722 case IORING_OP_ACCEPT
:
5723 return io_accept_prep(req
, sqe
);
5724 case IORING_OP_FALLOCATE
:
5725 return io_fallocate_prep(req
, sqe
);
5726 case IORING_OP_OPENAT
:
5727 return io_openat_prep(req
, sqe
);
5728 case IORING_OP_CLOSE
:
5729 return io_close_prep(req
, sqe
);
5730 case IORING_OP_FILES_UPDATE
:
5731 return io_files_update_prep(req
, sqe
);
5732 case IORING_OP_STATX
:
5733 return io_statx_prep(req
, sqe
);
5734 case IORING_OP_FADVISE
:
5735 return io_fadvise_prep(req
, sqe
);
5736 case IORING_OP_MADVISE
:
5737 return io_madvise_prep(req
, sqe
);
5738 case IORING_OP_OPENAT2
:
5739 return io_openat2_prep(req
, sqe
);
5740 case IORING_OP_EPOLL_CTL
:
5741 return io_epoll_ctl_prep(req
, sqe
);
5742 case IORING_OP_SPLICE
:
5743 return io_splice_prep(req
, sqe
);
5744 case IORING_OP_PROVIDE_BUFFERS
:
5745 return io_provide_buffers_prep(req
, sqe
);
5746 case IORING_OP_REMOVE_BUFFERS
:
5747 return io_remove_buffers_prep(req
, sqe
);
5749 return io_tee_prep(req
, sqe
);
5752 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5757 static int io_req_defer_prep(struct io_kiocb
*req
,
5758 const struct io_uring_sqe
*sqe
)
5762 if (io_alloc_async_data(req
))
5764 return io_req_prep(req
, sqe
);
5767 static u32
io_get_sequence(struct io_kiocb
*req
)
5769 struct io_kiocb
*pos
;
5770 struct io_ring_ctx
*ctx
= req
->ctx
;
5771 u32 total_submitted
, nr_reqs
= 1;
5773 if (req
->flags
& REQ_F_LINK_HEAD
)
5774 list_for_each_entry(pos
, &req
->link_list
, link_list
)
5777 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5778 return total_submitted
- nr_reqs
;
5781 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5783 struct io_ring_ctx
*ctx
= req
->ctx
;
5784 struct io_defer_entry
*de
;
5788 /* Still need defer if there is pending req in defer list. */
5789 if (likely(list_empty_careful(&ctx
->defer_list
) &&
5790 !(req
->flags
& REQ_F_IO_DRAIN
)))
5793 seq
= io_get_sequence(req
);
5794 /* Still a chance to pass the sequence check */
5795 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
5798 if (!req
->async_data
) {
5799 ret
= io_req_defer_prep(req
, sqe
);
5803 io_prep_async_link(req
);
5804 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
5808 spin_lock_irq(&ctx
->completion_lock
);
5809 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
5810 spin_unlock_irq(&ctx
->completion_lock
);
5812 io_queue_async_work(req
);
5813 return -EIOCBQUEUED
;
5816 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5819 list_add_tail(&de
->list
, &ctx
->defer_list
);
5820 spin_unlock_irq(&ctx
->completion_lock
);
5821 return -EIOCBQUEUED
;
5824 static void io_req_drop_files(struct io_kiocb
*req
)
5826 struct io_ring_ctx
*ctx
= req
->ctx
;
5827 unsigned long flags
;
5829 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
5830 list_del(&req
->inflight_entry
);
5831 if (waitqueue_active(&ctx
->inflight_wait
))
5832 wake_up(&ctx
->inflight_wait
);
5833 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
5834 req
->flags
&= ~REQ_F_INFLIGHT
;
5835 put_files_struct(req
->work
.identity
->files
);
5836 put_nsproxy(req
->work
.identity
->nsproxy
);
5837 req
->work
.flags
&= ~IO_WQ_WORK_FILES
;
5840 static void __io_clean_op(struct io_kiocb
*req
)
5842 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
5843 switch (req
->opcode
) {
5844 case IORING_OP_READV
:
5845 case IORING_OP_READ_FIXED
:
5846 case IORING_OP_READ
:
5847 kfree((void *)(unsigned long)req
->rw
.addr
);
5849 case IORING_OP_RECVMSG
:
5850 case IORING_OP_RECV
:
5851 kfree(req
->sr_msg
.kbuf
);
5854 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
5857 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
5858 switch (req
->opcode
) {
5859 case IORING_OP_READV
:
5860 case IORING_OP_READ_FIXED
:
5861 case IORING_OP_READ
:
5862 case IORING_OP_WRITEV
:
5863 case IORING_OP_WRITE_FIXED
:
5864 case IORING_OP_WRITE
: {
5865 struct io_async_rw
*io
= req
->async_data
;
5867 kfree(io
->free_iovec
);
5870 case IORING_OP_RECVMSG
:
5871 case IORING_OP_SENDMSG
: {
5872 struct io_async_msghdr
*io
= req
->async_data
;
5873 if (io
->iov
!= io
->fast_iov
)
5877 case IORING_OP_SPLICE
:
5879 io_put_file(req
, req
->splice
.file_in
,
5880 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
5882 case IORING_OP_OPENAT
:
5883 case IORING_OP_OPENAT2
:
5884 if (req
->open
.filename
)
5885 putname(req
->open
.filename
);
5888 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5891 if (req
->flags
& REQ_F_INFLIGHT
)
5892 io_req_drop_files(req
);
5895 static int io_issue_sqe(struct io_kiocb
*req
, bool force_nonblock
,
5896 struct io_comp_state
*cs
)
5898 struct io_ring_ctx
*ctx
= req
->ctx
;
5901 switch (req
->opcode
) {
5903 ret
= io_nop(req
, cs
);
5905 case IORING_OP_READV
:
5906 case IORING_OP_READ_FIXED
:
5907 case IORING_OP_READ
:
5908 ret
= io_read(req
, force_nonblock
, cs
);
5910 case IORING_OP_WRITEV
:
5911 case IORING_OP_WRITE_FIXED
:
5912 case IORING_OP_WRITE
:
5913 ret
= io_write(req
, force_nonblock
, cs
);
5915 case IORING_OP_FSYNC
:
5916 ret
= io_fsync(req
, force_nonblock
);
5918 case IORING_OP_POLL_ADD
:
5919 ret
= io_poll_add(req
);
5921 case IORING_OP_POLL_REMOVE
:
5922 ret
= io_poll_remove(req
);
5924 case IORING_OP_SYNC_FILE_RANGE
:
5925 ret
= io_sync_file_range(req
, force_nonblock
);
5927 case IORING_OP_SENDMSG
:
5928 ret
= io_sendmsg(req
, force_nonblock
, cs
);
5930 case IORING_OP_SEND
:
5931 ret
= io_send(req
, force_nonblock
, cs
);
5933 case IORING_OP_RECVMSG
:
5934 ret
= io_recvmsg(req
, force_nonblock
, cs
);
5936 case IORING_OP_RECV
:
5937 ret
= io_recv(req
, force_nonblock
, cs
);
5939 case IORING_OP_TIMEOUT
:
5940 ret
= io_timeout(req
);
5942 case IORING_OP_TIMEOUT_REMOVE
:
5943 ret
= io_timeout_remove(req
);
5945 case IORING_OP_ACCEPT
:
5946 ret
= io_accept(req
, force_nonblock
, cs
);
5948 case IORING_OP_CONNECT
:
5949 ret
= io_connect(req
, force_nonblock
, cs
);
5951 case IORING_OP_ASYNC_CANCEL
:
5952 ret
= io_async_cancel(req
);
5954 case IORING_OP_FALLOCATE
:
5955 ret
= io_fallocate(req
, force_nonblock
);
5957 case IORING_OP_OPENAT
:
5958 ret
= io_openat(req
, force_nonblock
);
5960 case IORING_OP_CLOSE
:
5961 ret
= io_close(req
, force_nonblock
, cs
);
5963 case IORING_OP_FILES_UPDATE
:
5964 ret
= io_files_update(req
, force_nonblock
, cs
);
5966 case IORING_OP_STATX
:
5967 ret
= io_statx(req
, force_nonblock
);
5969 case IORING_OP_FADVISE
:
5970 ret
= io_fadvise(req
, force_nonblock
);
5972 case IORING_OP_MADVISE
:
5973 ret
= io_madvise(req
, force_nonblock
);
5975 case IORING_OP_OPENAT2
:
5976 ret
= io_openat2(req
, force_nonblock
);
5978 case IORING_OP_EPOLL_CTL
:
5979 ret
= io_epoll_ctl(req
, force_nonblock
, cs
);
5981 case IORING_OP_SPLICE
:
5982 ret
= io_splice(req
, force_nonblock
);
5984 case IORING_OP_PROVIDE_BUFFERS
:
5985 ret
= io_provide_buffers(req
, force_nonblock
, cs
);
5987 case IORING_OP_REMOVE_BUFFERS
:
5988 ret
= io_remove_buffers(req
, force_nonblock
, cs
);
5991 ret
= io_tee(req
, force_nonblock
);
6001 /* If the op doesn't have a file, we're not polling for it */
6002 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
6003 const bool in_async
= io_wq_current_is_worker();
6005 /* workqueue context doesn't hold uring_lock, grab it now */
6007 mutex_lock(&ctx
->uring_lock
);
6009 io_iopoll_req_issued(req
);
6012 mutex_unlock(&ctx
->uring_lock
);
6018 static struct io_wq_work
*io_wq_submit_work(struct io_wq_work
*work
)
6020 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6021 struct io_kiocb
*timeout
;
6024 timeout
= io_prep_linked_timeout(req
);
6026 io_queue_linked_timeout(timeout
);
6028 /* if NO_CANCEL is set, we must still run the work */
6029 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
6030 IO_WQ_WORK_CANCEL
) {
6036 ret
= io_issue_sqe(req
, false, NULL
);
6038 * We can get EAGAIN for polled IO even though we're
6039 * forcing a sync submission from here, since we can't
6040 * wait for request slots on the block side.
6049 req_set_fail_links(req
);
6050 io_req_complete(req
, ret
);
6053 return io_steal_work(req
);
6056 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
6059 struct fixed_file_table
*table
;
6061 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
6062 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
6065 static struct file
*io_file_get(struct io_submit_state
*state
,
6066 struct io_kiocb
*req
, int fd
, bool fixed
)
6068 struct io_ring_ctx
*ctx
= req
->ctx
;
6072 if (unlikely((unsigned int)fd
>= ctx
->nr_user_files
))
6074 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
6075 file
= io_file_from_index(ctx
, fd
);
6077 req
->fixed_file_refs
= &ctx
->file_data
->node
->refs
;
6078 percpu_ref_get(req
->fixed_file_refs
);
6081 trace_io_uring_file_get(ctx
, fd
);
6082 file
= __io_file_get(state
, fd
);
6088 static int io_req_set_file(struct io_submit_state
*state
, struct io_kiocb
*req
,
6093 fixed
= (req
->flags
& REQ_F_FIXED_FILE
) != 0;
6094 if (unlikely(!fixed
&& io_async_submit(req
->ctx
)))
6097 req
->file
= io_file_get(state
, req
, fd
, fixed
);
6098 if (req
->file
|| io_op_defs
[req
->opcode
].needs_file_no_error
)
6103 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6105 struct io_timeout_data
*data
= container_of(timer
,
6106 struct io_timeout_data
, timer
);
6107 struct io_kiocb
*req
= data
->req
;
6108 struct io_ring_ctx
*ctx
= req
->ctx
;
6109 struct io_kiocb
*prev
= NULL
;
6110 unsigned long flags
;
6112 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6115 * We don't expect the list to be empty, that will only happen if we
6116 * race with the completion of the linked work.
6118 if (!list_empty(&req
->link_list
)) {
6119 prev
= list_entry(req
->link_list
.prev
, struct io_kiocb
,
6121 if (refcount_inc_not_zero(&prev
->refs
)) {
6122 list_del_init(&req
->link_list
);
6123 prev
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6128 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6131 req_set_fail_links(prev
);
6132 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6135 io_req_complete(req
, -ETIME
);
6137 return HRTIMER_NORESTART
;
6140 static void __io_queue_linked_timeout(struct io_kiocb
*req
)
6143 * If the list is now empty, then our linked request finished before
6144 * we got a chance to setup the timer
6146 if (!list_empty(&req
->link_list
)) {
6147 struct io_timeout_data
*data
= req
->async_data
;
6149 data
->timer
.function
= io_link_timeout_fn
;
6150 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6155 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6157 struct io_ring_ctx
*ctx
= req
->ctx
;
6159 spin_lock_irq(&ctx
->completion_lock
);
6160 __io_queue_linked_timeout(req
);
6161 spin_unlock_irq(&ctx
->completion_lock
);
6163 /* drop submission reference */
6167 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6169 struct io_kiocb
*nxt
;
6171 if (!(req
->flags
& REQ_F_LINK_HEAD
))
6173 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
6176 nxt
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
6178 if (!nxt
|| nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6181 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6185 static void __io_queue_sqe(struct io_kiocb
*req
, struct io_comp_state
*cs
)
6187 struct io_kiocb
*linked_timeout
;
6188 struct io_kiocb
*nxt
;
6189 const struct cred
*old_creds
= NULL
;
6193 linked_timeout
= io_prep_linked_timeout(req
);
6195 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) && req
->work
.identity
->creds
&&
6196 req
->work
.identity
->creds
!= current_cred()) {
6198 revert_creds(old_creds
);
6199 if (old_creds
== req
->work
.identity
->creds
)
6200 old_creds
= NULL
; /* restored original creds */
6202 old_creds
= override_creds(req
->work
.identity
->creds
);
6203 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
6206 ret
= io_issue_sqe(req
, true, cs
);
6209 * We async punt it if the file wasn't marked NOWAIT, or if the file
6210 * doesn't support non-blocking read/write attempts
6212 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6213 if (!io_arm_poll_handler(req
)) {
6216 * Queued up for async execution, worker will release
6217 * submit reference when the iocb is actually submitted.
6219 io_queue_async_work(req
);
6223 io_queue_linked_timeout(linked_timeout
);
6227 if (unlikely(ret
)) {
6228 /* un-prep timeout, so it'll be killed as any other linked */
6229 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6230 req_set_fail_links(req
);
6232 io_req_complete(req
, ret
);
6236 /* drop submission reference */
6237 nxt
= io_put_req_find_next(req
);
6239 io_queue_linked_timeout(linked_timeout
);
6244 if (req
->flags
& REQ_F_FORCE_ASYNC
)
6250 revert_creds(old_creds
);
6253 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6254 struct io_comp_state
*cs
)
6258 ret
= io_req_defer(req
, sqe
);
6260 if (ret
!= -EIOCBQUEUED
) {
6262 req_set_fail_links(req
);
6264 io_req_complete(req
, ret
);
6266 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6267 if (!req
->async_data
) {
6268 ret
= io_req_defer_prep(req
, sqe
);
6274 * Never try inline submit of IOSQE_ASYNC is set, go straight
6275 * to async execution.
6277 io_req_init_async(req
);
6278 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
6279 io_queue_async_work(req
);
6282 ret
= io_req_prep(req
, sqe
);
6286 __io_queue_sqe(req
, cs
);
6290 static inline void io_queue_link_head(struct io_kiocb
*req
,
6291 struct io_comp_state
*cs
)
6293 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6295 io_req_complete(req
, -ECANCELED
);
6297 io_queue_sqe(req
, NULL
, cs
);
6300 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6301 struct io_kiocb
**link
, struct io_comp_state
*cs
)
6303 struct io_ring_ctx
*ctx
= req
->ctx
;
6307 * If we already have a head request, queue this one for async
6308 * submittal once the head completes. If we don't have a head but
6309 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6310 * submitted sync once the chain is complete. If none of those
6311 * conditions are true (normal request), then just queue it.
6314 struct io_kiocb
*head
= *link
;
6317 * Taking sequential execution of a link, draining both sides
6318 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6319 * requests in the link. So, it drains the head and the
6320 * next after the link request. The last one is done via
6321 * drain_next flag to persist the effect across calls.
6323 if (req
->flags
& REQ_F_IO_DRAIN
) {
6324 head
->flags
|= REQ_F_IO_DRAIN
;
6325 ctx
->drain_next
= 1;
6327 ret
= io_req_defer_prep(req
, sqe
);
6328 if (unlikely(ret
)) {
6329 /* fail even hard links since we don't submit */
6330 head
->flags
|= REQ_F_FAIL_LINK
;
6333 trace_io_uring_link(ctx
, req
, head
);
6334 list_add_tail(&req
->link_list
, &head
->link_list
);
6336 /* last request of a link, enqueue the link */
6337 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6338 io_queue_link_head(head
, cs
);
6342 if (unlikely(ctx
->drain_next
)) {
6343 req
->flags
|= REQ_F_IO_DRAIN
;
6344 ctx
->drain_next
= 0;
6346 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6347 req
->flags
|= REQ_F_LINK_HEAD
;
6348 INIT_LIST_HEAD(&req
->link_list
);
6350 ret
= io_req_defer_prep(req
, sqe
);
6352 req
->flags
|= REQ_F_FAIL_LINK
;
6355 io_queue_sqe(req
, sqe
, cs
);
6363 * Batched submission is done, ensure local IO is flushed out.
6365 static void io_submit_state_end(struct io_submit_state
*state
)
6367 if (!list_empty(&state
->comp
.list
))
6368 io_submit_flush_completions(&state
->comp
);
6369 blk_finish_plug(&state
->plug
);
6370 io_state_file_put(state
);
6371 if (state
->free_reqs
)
6372 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
6376 * Start submission side cache.
6378 static void io_submit_state_start(struct io_submit_state
*state
,
6379 struct io_ring_ctx
*ctx
, unsigned int max_ios
)
6381 blk_start_plug(&state
->plug
);
6383 INIT_LIST_HEAD(&state
->comp
.list
);
6384 state
->comp
.ctx
= ctx
;
6385 state
->free_reqs
= 0;
6387 state
->ios_left
= max_ios
;
6390 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6392 struct io_rings
*rings
= ctx
->rings
;
6395 * Ensure any loads from the SQEs are done at this point,
6396 * since once we write the new head, the application could
6397 * write new data to them.
6399 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6403 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6404 * that is mapped by userspace. This means that care needs to be taken to
6405 * ensure that reads are stable, as we cannot rely on userspace always
6406 * being a good citizen. If members of the sqe are validated and then later
6407 * used, it's important that those reads are done through READ_ONCE() to
6408 * prevent a re-load down the line.
6410 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6412 u32
*sq_array
= ctx
->sq_array
;
6416 * The cached sq head (or cq tail) serves two purposes:
6418 * 1) allows us to batch the cost of updating the user visible
6420 * 2) allows the kernel side to track the head on its own, even
6421 * though the application is the one updating it.
6423 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
6424 if (likely(head
< ctx
->sq_entries
))
6425 return &ctx
->sq_sqes
[head
];
6427 /* drop invalid entries */
6428 ctx
->cached_sq_dropped
++;
6429 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6433 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
6435 ctx
->cached_sq_head
++;
6439 * Check SQE restrictions (opcode and flags).
6441 * Returns 'true' if SQE is allowed, 'false' otherwise.
6443 static inline bool io_check_restriction(struct io_ring_ctx
*ctx
,
6444 struct io_kiocb
*req
,
6445 unsigned int sqe_flags
)
6447 if (!ctx
->restricted
)
6450 if (!test_bit(req
->opcode
, ctx
->restrictions
.sqe_op
))
6453 if ((sqe_flags
& ctx
->restrictions
.sqe_flags_required
) !=
6454 ctx
->restrictions
.sqe_flags_required
)
6457 if (sqe_flags
& ~(ctx
->restrictions
.sqe_flags_allowed
|
6458 ctx
->restrictions
.sqe_flags_required
))
6464 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6465 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6466 IOSQE_BUFFER_SELECT)
6468 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6469 const struct io_uring_sqe
*sqe
,
6470 struct io_submit_state
*state
)
6472 unsigned int sqe_flags
;
6475 req
->opcode
= READ_ONCE(sqe
->opcode
);
6476 req
->user_data
= READ_ONCE(sqe
->user_data
);
6477 req
->async_data
= NULL
;
6481 /* one is dropped after submission, the other at completion */
6482 refcount_set(&req
->refs
, 2);
6483 req
->task
= current
;
6486 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6489 if (unlikely(io_sq_thread_acquire_mm(ctx
, req
)))
6492 sqe_flags
= READ_ONCE(sqe
->flags
);
6493 /* enforce forwards compatibility on users */
6494 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6497 if (unlikely(!io_check_restriction(ctx
, req
, sqe_flags
)))
6500 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6501 !io_op_defs
[req
->opcode
].buffer_select
)
6504 id
= READ_ONCE(sqe
->personality
);
6506 struct io_identity
*iod
;
6508 io_req_init_async(req
);
6509 iod
= idr_find(&ctx
->personality_idr
, id
);
6512 refcount_inc(&iod
->count
);
6513 io_put_identity(current
->io_uring
, req
);
6514 get_cred(iod
->creds
);
6515 req
->work
.identity
= iod
;
6516 req
->work
.flags
|= IO_WQ_WORK_CREDS
;
6519 /* same numerical values with corresponding REQ_F_*, safe to copy */
6520 req
->flags
|= sqe_flags
;
6522 if (!io_op_defs
[req
->opcode
].needs_file
)
6525 ret
= io_req_set_file(state
, req
, READ_ONCE(sqe
->fd
));
6530 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
)
6532 struct io_submit_state state
;
6533 struct io_kiocb
*link
= NULL
;
6534 int i
, submitted
= 0;
6536 /* if we have a backlog and couldn't flush it all, return BUSY */
6537 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6538 if (!list_empty(&ctx
->cq_overflow_list
) &&
6539 !io_cqring_overflow_flush(ctx
, false, NULL
, NULL
))
6543 /* make sure SQ entry isn't read before tail */
6544 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6546 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6549 percpu_counter_add(¤t
->io_uring
->inflight
, nr
);
6550 refcount_add(nr
, ¤t
->usage
);
6552 io_submit_state_start(&state
, ctx
, nr
);
6554 for (i
= 0; i
< nr
; i
++) {
6555 const struct io_uring_sqe
*sqe
;
6556 struct io_kiocb
*req
;
6559 sqe
= io_get_sqe(ctx
);
6560 if (unlikely(!sqe
)) {
6561 io_consume_sqe(ctx
);
6564 req
= io_alloc_req(ctx
, &state
);
6565 if (unlikely(!req
)) {
6567 submitted
= -EAGAIN
;
6570 io_consume_sqe(ctx
);
6571 /* will complete beyond this point, count as submitted */
6574 err
= io_init_req(ctx
, req
, sqe
, &state
);
6575 if (unlikely(err
)) {
6578 io_req_complete(req
, err
);
6582 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6583 true, io_async_submit(ctx
));
6584 err
= io_submit_sqe(req
, sqe
, &link
, &state
.comp
);
6589 if (unlikely(submitted
!= nr
)) {
6590 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6591 struct io_uring_task
*tctx
= current
->io_uring
;
6592 int unused
= nr
- ref_used
;
6594 percpu_ref_put_many(&ctx
->refs
, unused
);
6595 percpu_counter_sub(&tctx
->inflight
, unused
);
6596 put_task_struct_many(current
, unused
);
6599 io_queue_link_head(link
, &state
.comp
);
6600 io_submit_state_end(&state
);
6602 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6603 io_commit_sqring(ctx
);
6608 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6610 /* Tell userspace we may need a wakeup call */
6611 spin_lock_irq(&ctx
->completion_lock
);
6612 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6613 spin_unlock_irq(&ctx
->completion_lock
);
6616 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6618 spin_lock_irq(&ctx
->completion_lock
);
6619 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6620 spin_unlock_irq(&ctx
->completion_lock
);
6623 static int io_sq_wake_function(struct wait_queue_entry
*wqe
, unsigned mode
,
6624 int sync
, void *key
)
6626 struct io_ring_ctx
*ctx
= container_of(wqe
, struct io_ring_ctx
, sqo_wait_entry
);
6629 ret
= autoremove_wake_function(wqe
, mode
, sync
, key
);
6631 unsigned long flags
;
6633 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6634 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6635 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6646 static enum sq_ret
__io_sq_thread(struct io_ring_ctx
*ctx
,
6647 unsigned long start_jiffies
, bool cap_entries
)
6649 unsigned long timeout
= start_jiffies
+ ctx
->sq_thread_idle
;
6650 struct io_sq_data
*sqd
= ctx
->sq_data
;
6651 unsigned int to_submit
;
6655 if (!list_empty(&ctx
->iopoll_list
)) {
6656 unsigned nr_events
= 0;
6658 mutex_lock(&ctx
->uring_lock
);
6659 if (!list_empty(&ctx
->iopoll_list
) && !need_resched())
6660 io_do_iopoll(ctx
, &nr_events
, 0);
6661 mutex_unlock(&ctx
->uring_lock
);
6664 to_submit
= io_sqring_entries(ctx
);
6667 * If submit got -EBUSY, flag us as needing the application
6668 * to enter the kernel to reap and flush events.
6670 if (!to_submit
|| ret
== -EBUSY
|| need_resched()) {
6672 * Drop cur_mm before scheduling, we can't hold it for
6673 * long periods (or over schedule()). Do this before
6674 * adding ourselves to the waitqueue, as the unuse/drop
6677 io_sq_thread_drop_mm();
6680 * We're polling. If we're within the defined idle
6681 * period, then let us spin without work before going
6682 * to sleep. The exception is if we got EBUSY doing
6683 * more IO, we should wait for the application to
6684 * reap events and wake us up.
6686 if (!list_empty(&ctx
->iopoll_list
) || need_resched() ||
6687 (!time_after(jiffies
, timeout
) && ret
!= -EBUSY
&&
6688 !percpu_ref_is_dying(&ctx
->refs
)))
6691 prepare_to_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
,
6692 TASK_INTERRUPTIBLE
);
6695 * While doing polled IO, before going to sleep, we need
6696 * to check if there are new reqs added to iopoll_list,
6697 * it is because reqs may have been punted to io worker
6698 * and will be added to iopoll_list later, hence check
6699 * the iopoll_list again.
6701 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6702 !list_empty_careful(&ctx
->iopoll_list
)) {
6703 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
6707 to_submit
= io_sqring_entries(ctx
);
6708 if (!to_submit
|| ret
== -EBUSY
)
6712 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
6713 io_ring_clear_wakeup_flag(ctx
);
6715 /* if we're handling multiple rings, cap submit size for fairness */
6716 if (cap_entries
&& to_submit
> 8)
6719 mutex_lock(&ctx
->uring_lock
);
6720 if (likely(!percpu_ref_is_dying(&ctx
->refs
)))
6721 ret
= io_submit_sqes(ctx
, to_submit
);
6722 mutex_unlock(&ctx
->uring_lock
);
6724 if (!io_sqring_full(ctx
) && wq_has_sleeper(&ctx
->sqo_sq_wait
))
6725 wake_up(&ctx
->sqo_sq_wait
);
6727 return SQT_DID_WORK
;
6730 static void io_sqd_init_new(struct io_sq_data
*sqd
)
6732 struct io_ring_ctx
*ctx
;
6734 while (!list_empty(&sqd
->ctx_new_list
)) {
6735 ctx
= list_first_entry(&sqd
->ctx_new_list
, struct io_ring_ctx
, sqd_list
);
6736 init_wait(&ctx
->sqo_wait_entry
);
6737 ctx
->sqo_wait_entry
.func
= io_sq_wake_function
;
6738 list_move_tail(&ctx
->sqd_list
, &sqd
->ctx_list
);
6739 complete(&ctx
->sq_thread_comp
);
6743 static int io_sq_thread(void *data
)
6745 struct cgroup_subsys_state
*cur_css
= NULL
;
6746 const struct cred
*old_cred
= NULL
;
6747 struct io_sq_data
*sqd
= data
;
6748 struct io_ring_ctx
*ctx
;
6749 unsigned long start_jiffies
;
6751 start_jiffies
= jiffies
;
6752 while (!kthread_should_stop()) {
6753 enum sq_ret ret
= 0;
6757 * Any changes to the sqd lists are synchronized through the
6758 * kthread parking. This synchronizes the thread vs users,
6759 * the users are synchronized on the sqd->ctx_lock.
6761 if (kthread_should_park())
6764 if (unlikely(!list_empty(&sqd
->ctx_new_list
)))
6765 io_sqd_init_new(sqd
);
6767 cap_entries
= !list_is_singular(&sqd
->ctx_list
);
6769 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
) {
6770 if (current
->cred
!= ctx
->creds
) {
6772 revert_creds(old_cred
);
6773 old_cred
= override_creds(ctx
->creds
);
6775 io_sq_thread_associate_blkcg(ctx
, &cur_css
);
6777 current
->loginuid
= ctx
->loginuid
;
6778 current
->sessionid
= ctx
->sessionid
;
6781 ret
|= __io_sq_thread(ctx
, start_jiffies
, cap_entries
);
6783 io_sq_thread_drop_mm();
6786 if (ret
& SQT_SPIN
) {
6789 } else if (ret
== SQT_IDLE
) {
6790 if (kthread_should_park())
6792 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6793 io_ring_set_wakeup_flag(ctx
);
6795 start_jiffies
= jiffies
;
6796 list_for_each_entry(ctx
, &sqd
->ctx_list
, sqd_list
)
6797 io_ring_clear_wakeup_flag(ctx
);
6804 io_sq_thread_unassociate_blkcg();
6806 revert_creds(old_cred
);
6813 struct io_wait_queue
{
6814 struct wait_queue_entry wq
;
6815 struct io_ring_ctx
*ctx
;
6817 unsigned nr_timeouts
;
6820 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
6822 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6825 * Wake up if we have enough events, or if a timeout occurred since we
6826 * started waiting. For timeouts, we always want to return to userspace,
6827 * regardless of event count.
6829 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
6830 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6833 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6834 int wake_flags
, void *key
)
6836 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6839 /* use noflush == true, as we can't safely rely on locking context */
6840 if (!io_should_wake(iowq
, true))
6843 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6846 static int io_run_task_work_sig(void)
6848 if (io_run_task_work())
6850 if (!signal_pending(current
))
6852 if (current
->jobctl
& JOBCTL_TASK_WORK
) {
6853 spin_lock_irq(¤t
->sighand
->siglock
);
6854 current
->jobctl
&= ~JOBCTL_TASK_WORK
;
6855 recalc_sigpending();
6856 spin_unlock_irq(¤t
->sighand
->siglock
);
6863 * Wait until events become available, if we don't already have some. The
6864 * application must reap them itself, as they reside on the shared cq ring.
6866 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6867 const sigset_t __user
*sig
, size_t sigsz
)
6869 struct io_wait_queue iowq
= {
6872 .func
= io_wake_function
,
6873 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6876 .to_wait
= min_events
,
6878 struct io_rings
*rings
= ctx
->rings
;
6882 if (io_cqring_events(ctx
, false) >= min_events
)
6884 if (!io_run_task_work())
6889 #ifdef CONFIG_COMPAT
6890 if (in_compat_syscall())
6891 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6895 ret
= set_user_sigmask(sig
, sigsz
);
6901 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6902 trace_io_uring_cqring_wait(ctx
, min_events
);
6904 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
6905 TASK_INTERRUPTIBLE
);
6906 /* make sure we run task_work before checking for signals */
6907 ret
= io_run_task_work_sig();
6912 if (io_should_wake(&iowq
, false))
6916 finish_wait(&ctx
->wait
, &iowq
.wq
);
6918 restore_saved_sigmask_unless(ret
== -EINTR
);
6920 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
6923 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6925 #if defined(CONFIG_UNIX)
6926 if (ctx
->ring_sock
) {
6927 struct sock
*sock
= ctx
->ring_sock
->sk
;
6928 struct sk_buff
*skb
;
6930 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
6936 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6939 file
= io_file_from_index(ctx
, i
);
6946 static void io_file_ref_kill(struct percpu_ref
*ref
)
6948 struct fixed_file_data
*data
;
6950 data
= container_of(ref
, struct fixed_file_data
, refs
);
6951 complete(&data
->done
);
6954 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6956 struct fixed_file_data
*data
= ctx
->file_data
;
6957 struct fixed_file_ref_node
*ref_node
= NULL
;
6958 unsigned nr_tables
, i
;
6963 spin_lock(&data
->lock
);
6964 if (!list_empty(&data
->ref_list
))
6965 ref_node
= list_first_entry(&data
->ref_list
,
6966 struct fixed_file_ref_node
, node
);
6967 spin_unlock(&data
->lock
);
6969 percpu_ref_kill(&ref_node
->refs
);
6971 percpu_ref_kill(&data
->refs
);
6973 /* wait for all refs nodes to complete */
6974 flush_delayed_work(&ctx
->file_put_work
);
6975 wait_for_completion(&data
->done
);
6977 __io_sqe_files_unregister(ctx
);
6978 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
6979 for (i
= 0; i
< nr_tables
; i
++)
6980 kfree(data
->table
[i
].files
);
6982 percpu_ref_exit(&data
->refs
);
6984 ctx
->file_data
= NULL
;
6985 ctx
->nr_user_files
= 0;
6989 static void io_put_sq_data(struct io_sq_data
*sqd
)
6991 if (refcount_dec_and_test(&sqd
->refs
)) {
6993 * The park is a bit of a work-around, without it we get
6994 * warning spews on shutdown with SQPOLL set and affinity
6995 * set to a single CPU.
6998 kthread_park(sqd
->thread
);
6999 kthread_stop(sqd
->thread
);
7006 static struct io_sq_data
*io_attach_sq_data(struct io_uring_params
*p
)
7008 struct io_ring_ctx
*ctx_attach
;
7009 struct io_sq_data
*sqd
;
7012 f
= fdget(p
->wq_fd
);
7014 return ERR_PTR(-ENXIO
);
7015 if (f
.file
->f_op
!= &io_uring_fops
) {
7017 return ERR_PTR(-EINVAL
);
7020 ctx_attach
= f
.file
->private_data
;
7021 sqd
= ctx_attach
->sq_data
;
7024 return ERR_PTR(-EINVAL
);
7027 refcount_inc(&sqd
->refs
);
7032 static struct io_sq_data
*io_get_sq_data(struct io_uring_params
*p
)
7034 struct io_sq_data
*sqd
;
7036 if (p
->flags
& IORING_SETUP_ATTACH_WQ
)
7037 return io_attach_sq_data(p
);
7039 sqd
= kzalloc(sizeof(*sqd
), GFP_KERNEL
);
7041 return ERR_PTR(-ENOMEM
);
7043 refcount_set(&sqd
->refs
, 1);
7044 INIT_LIST_HEAD(&sqd
->ctx_list
);
7045 INIT_LIST_HEAD(&sqd
->ctx_new_list
);
7046 mutex_init(&sqd
->ctx_lock
);
7047 mutex_init(&sqd
->lock
);
7048 init_waitqueue_head(&sqd
->wait
);
7052 static void io_sq_thread_unpark(struct io_sq_data
*sqd
)
7053 __releases(&sqd
->lock
)
7057 kthread_unpark(sqd
->thread
);
7058 mutex_unlock(&sqd
->lock
);
7061 static void io_sq_thread_park(struct io_sq_data
*sqd
)
7062 __acquires(&sqd
->lock
)
7066 mutex_lock(&sqd
->lock
);
7067 kthread_park(sqd
->thread
);
7070 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
7072 struct io_sq_data
*sqd
= ctx
->sq_data
;
7077 * We may arrive here from the error branch in
7078 * io_sq_offload_create() where the kthread is created
7079 * without being waked up, thus wake it up now to make
7080 * sure the wait will complete.
7082 wake_up_process(sqd
->thread
);
7083 wait_for_completion(&ctx
->sq_thread_comp
);
7085 io_sq_thread_park(sqd
);
7088 mutex_lock(&sqd
->ctx_lock
);
7089 list_del(&ctx
->sqd_list
);
7090 mutex_unlock(&sqd
->ctx_lock
);
7093 finish_wait(&sqd
->wait
, &ctx
->sqo_wait_entry
);
7094 io_sq_thread_unpark(sqd
);
7097 io_put_sq_data(sqd
);
7098 ctx
->sq_data
= NULL
;
7102 static void io_finish_async(struct io_ring_ctx
*ctx
)
7104 io_sq_thread_stop(ctx
);
7107 io_wq_destroy(ctx
->io_wq
);
7112 #if defined(CONFIG_UNIX)
7114 * Ensure the UNIX gc is aware of our file set, so we are certain that
7115 * the io_uring can be safely unregistered on process exit, even if we have
7116 * loops in the file referencing.
7118 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
7120 struct sock
*sk
= ctx
->ring_sock
->sk
;
7121 struct scm_fp_list
*fpl
;
7122 struct sk_buff
*skb
;
7125 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
7129 skb
= alloc_skb(0, GFP_KERNEL
);
7138 fpl
->user
= get_uid(ctx
->user
);
7139 for (i
= 0; i
< nr
; i
++) {
7140 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
7144 fpl
->fp
[nr_files
] = get_file(file
);
7145 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
7150 fpl
->max
= SCM_MAX_FD
;
7151 fpl
->count
= nr_files
;
7152 UNIXCB(skb
).fp
= fpl
;
7153 skb
->destructor
= unix_destruct_scm
;
7154 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
7155 skb_queue_head(&sk
->sk_receive_queue
, skb
);
7157 for (i
= 0; i
< nr_files
; i
++)
7168 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7169 * causes regular reference counting to break down. We rely on the UNIX
7170 * garbage collection to take care of this problem for us.
7172 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7174 unsigned left
, total
;
7178 left
= ctx
->nr_user_files
;
7180 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
7182 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
7186 total
+= this_files
;
7192 while (total
< ctx
->nr_user_files
) {
7193 struct file
*file
= io_file_from_index(ctx
, total
);
7203 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
7209 static int io_sqe_alloc_file_tables(struct fixed_file_data
*file_data
,
7210 unsigned nr_tables
, unsigned nr_files
)
7214 for (i
= 0; i
< nr_tables
; i
++) {
7215 struct fixed_file_table
*table
= &file_data
->table
[i
];
7216 unsigned this_files
;
7218 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
7219 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
7223 nr_files
-= this_files
;
7229 for (i
= 0; i
< nr_tables
; i
++) {
7230 struct fixed_file_table
*table
= &file_data
->table
[i
];
7231 kfree(table
->files
);
7236 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
7238 #if defined(CONFIG_UNIX)
7239 struct sock
*sock
= ctx
->ring_sock
->sk
;
7240 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
7241 struct sk_buff
*skb
;
7244 __skb_queue_head_init(&list
);
7247 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7248 * remove this entry and rearrange the file array.
7250 skb
= skb_dequeue(head
);
7252 struct scm_fp_list
*fp
;
7254 fp
= UNIXCB(skb
).fp
;
7255 for (i
= 0; i
< fp
->count
; i
++) {
7258 if (fp
->fp
[i
] != file
)
7261 unix_notinflight(fp
->user
, fp
->fp
[i
]);
7262 left
= fp
->count
- 1 - i
;
7264 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
7265 left
* sizeof(struct file
*));
7272 __skb_queue_tail(&list
, skb
);
7282 __skb_queue_tail(&list
, skb
);
7284 skb
= skb_dequeue(head
);
7287 if (skb_peek(&list
)) {
7288 spin_lock_irq(&head
->lock
);
7289 while ((skb
= __skb_dequeue(&list
)) != NULL
)
7290 __skb_queue_tail(head
, skb
);
7291 spin_unlock_irq(&head
->lock
);
7298 struct io_file_put
{
7299 struct list_head list
;
7303 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
7305 struct fixed_file_data
*file_data
= ref_node
->file_data
;
7306 struct io_ring_ctx
*ctx
= file_data
->ctx
;
7307 struct io_file_put
*pfile
, *tmp
;
7309 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
7310 list_del(&pfile
->list
);
7311 io_ring_file_put(ctx
, pfile
->file
);
7315 spin_lock(&file_data
->lock
);
7316 list_del(&ref_node
->node
);
7317 spin_unlock(&file_data
->lock
);
7319 percpu_ref_exit(&ref_node
->refs
);
7321 percpu_ref_put(&file_data
->refs
);
7324 static void io_file_put_work(struct work_struct
*work
)
7326 struct io_ring_ctx
*ctx
;
7327 struct llist_node
*node
;
7329 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
7330 node
= llist_del_all(&ctx
->file_put_llist
);
7333 struct fixed_file_ref_node
*ref_node
;
7334 struct llist_node
*next
= node
->next
;
7336 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
7337 __io_file_put_work(ref_node
);
7342 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
7344 struct fixed_file_ref_node
*ref_node
;
7345 struct io_ring_ctx
*ctx
;
7349 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
7350 ctx
= ref_node
->file_data
->ctx
;
7352 if (percpu_ref_is_dying(&ctx
->file_data
->refs
))
7355 first_add
= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
7357 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
7359 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
7362 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
7363 struct io_ring_ctx
*ctx
)
7365 struct fixed_file_ref_node
*ref_node
;
7367 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7369 return ERR_PTR(-ENOMEM
);
7371 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
7374 return ERR_PTR(-ENOMEM
);
7376 INIT_LIST_HEAD(&ref_node
->node
);
7377 INIT_LIST_HEAD(&ref_node
->file_list
);
7378 ref_node
->file_data
= ctx
->file_data
;
7382 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
7384 percpu_ref_exit(&ref_node
->refs
);
7388 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7391 __s32 __user
*fds
= (__s32 __user
*) arg
;
7392 unsigned nr_tables
, i
;
7394 int fd
, ret
= -ENOMEM
;
7395 struct fixed_file_ref_node
*ref_node
;
7396 struct fixed_file_data
*file_data
;
7402 if (nr_args
> IORING_MAX_FIXED_FILES
)
7405 file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
7408 file_data
->ctx
= ctx
;
7409 init_completion(&file_data
->done
);
7410 INIT_LIST_HEAD(&file_data
->ref_list
);
7411 spin_lock_init(&file_data
->lock
);
7413 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7414 file_data
->table
= kcalloc(nr_tables
, sizeof(*file_data
->table
),
7416 if (!file_data
->table
)
7419 if (percpu_ref_init(&file_data
->refs
, io_file_ref_kill
,
7420 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
7423 if (io_sqe_alloc_file_tables(file_data
, nr_tables
, nr_args
))
7425 ctx
->file_data
= file_data
;
7427 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7428 struct fixed_file_table
*table
;
7431 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
))) {
7435 /* allow sparse sets */
7445 * Don't allow io_uring instances to be registered. If UNIX
7446 * isn't enabled, then this causes a reference cycle and this
7447 * instance can never get freed. If UNIX is enabled we'll
7448 * handle it just fine, but there's still no point in allowing
7449 * a ring fd as it doesn't support regular read/write anyway.
7451 if (file
->f_op
== &io_uring_fops
) {
7455 table
= &file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7456 index
= i
& IORING_FILE_TABLE_MASK
;
7457 table
->files
[index
] = file
;
7460 ret
= io_sqe_files_scm(ctx
);
7462 io_sqe_files_unregister(ctx
);
7466 ref_node
= alloc_fixed_file_ref_node(ctx
);
7467 if (IS_ERR(ref_node
)) {
7468 io_sqe_files_unregister(ctx
);
7469 return PTR_ERR(ref_node
);
7472 file_data
->node
= ref_node
;
7473 spin_lock(&file_data
->lock
);
7474 list_add(&ref_node
->node
, &file_data
->ref_list
);
7475 spin_unlock(&file_data
->lock
);
7476 percpu_ref_get(&file_data
->refs
);
7479 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7480 file
= io_file_from_index(ctx
, i
);
7484 for (i
= 0; i
< nr_tables
; i
++)
7485 kfree(file_data
->table
[i
].files
);
7486 ctx
->nr_user_files
= 0;
7488 percpu_ref_exit(&file_data
->refs
);
7490 kfree(file_data
->table
);
7492 ctx
->file_data
= NULL
;
7496 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7499 #if defined(CONFIG_UNIX)
7500 struct sock
*sock
= ctx
->ring_sock
->sk
;
7501 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7502 struct sk_buff
*skb
;
7505 * See if we can merge this file into an existing skb SCM_RIGHTS
7506 * file set. If there's no room, fall back to allocating a new skb
7507 * and filling it in.
7509 spin_lock_irq(&head
->lock
);
7510 skb
= skb_peek(head
);
7512 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7514 if (fpl
->count
< SCM_MAX_FD
) {
7515 __skb_unlink(skb
, head
);
7516 spin_unlock_irq(&head
->lock
);
7517 fpl
->fp
[fpl
->count
] = get_file(file
);
7518 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7520 spin_lock_irq(&head
->lock
);
7521 __skb_queue_head(head
, skb
);
7526 spin_unlock_irq(&head
->lock
);
7533 return __io_sqe_files_scm(ctx
, 1, index
);
7539 static int io_queue_file_removal(struct fixed_file_data
*data
,
7542 struct io_file_put
*pfile
;
7543 struct fixed_file_ref_node
*ref_node
= data
->node
;
7545 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
7550 list_add(&pfile
->list
, &ref_node
->file_list
);
7555 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7556 struct io_uring_files_update
*up
,
7559 struct fixed_file_data
*data
= ctx
->file_data
;
7560 struct fixed_file_ref_node
*ref_node
;
7565 bool needs_switch
= false;
7567 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7569 if (done
> ctx
->nr_user_files
)
7572 ref_node
= alloc_fixed_file_ref_node(ctx
);
7573 if (IS_ERR(ref_node
))
7574 return PTR_ERR(ref_node
);
7577 fds
= u64_to_user_ptr(up
->fds
);
7579 struct fixed_file_table
*table
;
7583 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7587 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
7588 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7589 index
= i
& IORING_FILE_TABLE_MASK
;
7590 if (table
->files
[index
]) {
7591 file
= table
->files
[index
];
7592 err
= io_queue_file_removal(data
, file
);
7595 table
->files
[index
] = NULL
;
7596 needs_switch
= true;
7605 * Don't allow io_uring instances to be registered. If
7606 * UNIX isn't enabled, then this causes a reference
7607 * cycle and this instance can never get freed. If UNIX
7608 * is enabled we'll handle it just fine, but there's
7609 * still no point in allowing a ring fd as it doesn't
7610 * support regular read/write anyway.
7612 if (file
->f_op
== &io_uring_fops
) {
7617 table
->files
[index
] = file
;
7618 err
= io_sqe_file_register(ctx
, file
, i
);
7620 table
->files
[index
] = NULL
;
7631 percpu_ref_kill(&data
->node
->refs
);
7632 spin_lock(&data
->lock
);
7633 list_add(&ref_node
->node
, &data
->ref_list
);
7634 data
->node
= ref_node
;
7635 spin_unlock(&data
->lock
);
7636 percpu_ref_get(&ctx
->file_data
->refs
);
7638 destroy_fixed_file_ref_node(ref_node
);
7640 return done
? done
: err
;
7643 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7646 struct io_uring_files_update up
;
7648 if (!ctx
->file_data
)
7652 if (copy_from_user(&up
, arg
, sizeof(up
)))
7657 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7660 static void io_free_work(struct io_wq_work
*work
)
7662 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7664 /* Consider that io_steal_work() relies on this ref */
7668 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
7669 struct io_uring_params
*p
)
7671 struct io_wq_data data
;
7673 struct io_ring_ctx
*ctx_attach
;
7674 unsigned int concurrency
;
7677 data
.user
= ctx
->user
;
7678 data
.free_work
= io_free_work
;
7679 data
.do_work
= io_wq_submit_work
;
7681 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
7682 /* Do QD, or 4 * CPUS, whatever is smallest */
7683 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7685 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
7686 if (IS_ERR(ctx
->io_wq
)) {
7687 ret
= PTR_ERR(ctx
->io_wq
);
7693 f
= fdget(p
->wq_fd
);
7697 if (f
.file
->f_op
!= &io_uring_fops
) {
7702 ctx_attach
= f
.file
->private_data
;
7703 /* @io_wq is protected by holding the fd */
7704 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
7709 ctx
->io_wq
= ctx_attach
->io_wq
;
7715 static int io_uring_alloc_task_context(struct task_struct
*task
)
7717 struct io_uring_task
*tctx
;
7720 tctx
= kmalloc(sizeof(*tctx
), GFP_KERNEL
);
7721 if (unlikely(!tctx
))
7724 ret
= percpu_counter_init(&tctx
->inflight
, 0, GFP_KERNEL
);
7725 if (unlikely(ret
)) {
7731 init_waitqueue_head(&tctx
->wait
);
7734 io_init_identity(&tctx
->__identity
);
7735 tctx
->identity
= &tctx
->__identity
;
7736 task
->io_uring
= tctx
;
7740 void __io_uring_free(struct task_struct
*tsk
)
7742 struct io_uring_task
*tctx
= tsk
->io_uring
;
7744 WARN_ON_ONCE(!xa_empty(&tctx
->xa
));
7745 WARN_ON_ONCE(refcount_read(&tctx
->identity
->count
) != 1);
7746 if (tctx
->identity
!= &tctx
->__identity
)
7747 kfree(tctx
->identity
);
7748 percpu_counter_destroy(&tctx
->inflight
);
7750 tsk
->io_uring
= NULL
;
7753 static int io_sq_offload_create(struct io_ring_ctx
*ctx
,
7754 struct io_uring_params
*p
)
7758 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7759 struct io_sq_data
*sqd
;
7762 if (!capable(CAP_SYS_ADMIN
))
7765 sqd
= io_get_sq_data(p
);
7772 io_sq_thread_park(sqd
);
7773 mutex_lock(&sqd
->ctx_lock
);
7774 list_add(&ctx
->sqd_list
, &sqd
->ctx_new_list
);
7775 mutex_unlock(&sqd
->ctx_lock
);
7776 io_sq_thread_unpark(sqd
);
7778 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
7779 if (!ctx
->sq_thread_idle
)
7780 ctx
->sq_thread_idle
= HZ
;
7785 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7786 int cpu
= p
->sq_thread_cpu
;
7789 if (cpu
>= nr_cpu_ids
)
7791 if (!cpu_online(cpu
))
7794 sqd
->thread
= kthread_create_on_cpu(io_sq_thread
, sqd
,
7795 cpu
, "io_uring-sq");
7797 sqd
->thread
= kthread_create(io_sq_thread
, sqd
,
7800 if (IS_ERR(sqd
->thread
)) {
7801 ret
= PTR_ERR(sqd
->thread
);
7805 ret
= io_uring_alloc_task_context(sqd
->thread
);
7808 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7809 /* Can't have SQ_AFF without SQPOLL */
7815 ret
= io_init_wq_offload(ctx
, p
);
7821 io_finish_async(ctx
);
7825 static void io_sq_offload_start(struct io_ring_ctx
*ctx
)
7827 struct io_sq_data
*sqd
= ctx
->sq_data
;
7829 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && sqd
->thread
)
7830 wake_up_process(sqd
->thread
);
7833 static inline void __io_unaccount_mem(struct user_struct
*user
,
7834 unsigned long nr_pages
)
7836 atomic_long_sub(nr_pages
, &user
->locked_vm
);
7839 static inline int __io_account_mem(struct user_struct
*user
,
7840 unsigned long nr_pages
)
7842 unsigned long page_limit
, cur_pages
, new_pages
;
7844 /* Don't allow more pages than we can safely lock */
7845 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
7848 cur_pages
= atomic_long_read(&user
->locked_vm
);
7849 new_pages
= cur_pages
+ nr_pages
;
7850 if (new_pages
> page_limit
)
7852 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
7853 new_pages
) != cur_pages
);
7858 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7859 enum io_mem_account acct
)
7862 __io_unaccount_mem(ctx
->user
, nr_pages
);
7864 if (ctx
->mm_account
) {
7865 if (acct
== ACCT_LOCKED
)
7866 ctx
->mm_account
->locked_vm
-= nr_pages
;
7867 else if (acct
== ACCT_PINNED
)
7868 atomic64_sub(nr_pages
, &ctx
->mm_account
->pinned_vm
);
7872 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7873 enum io_mem_account acct
)
7877 if (ctx
->limit_mem
) {
7878 ret
= __io_account_mem(ctx
->user
, nr_pages
);
7883 if (ctx
->mm_account
) {
7884 if (acct
== ACCT_LOCKED
)
7885 ctx
->mm_account
->locked_vm
+= nr_pages
;
7886 else if (acct
== ACCT_PINNED
)
7887 atomic64_add(nr_pages
, &ctx
->mm_account
->pinned_vm
);
7893 static void io_mem_free(void *ptr
)
7900 page
= virt_to_head_page(ptr
);
7901 if (put_page_testzero(page
))
7902 free_compound_page(page
);
7905 static void *io_mem_alloc(size_t size
)
7907 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
7910 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
7913 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
7916 struct io_rings
*rings
;
7917 size_t off
, sq_array_size
;
7919 off
= struct_size(rings
, cqes
, cq_entries
);
7920 if (off
== SIZE_MAX
)
7924 off
= ALIGN(off
, SMP_CACHE_BYTES
);
7932 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
7933 if (sq_array_size
== SIZE_MAX
)
7936 if (check_add_overflow(off
, sq_array_size
, &off
))
7942 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
7946 pages
= (size_t)1 << get_order(
7947 rings_size(sq_entries
, cq_entries
, NULL
));
7948 pages
+= (size_t)1 << get_order(
7949 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
7954 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
7958 if (!ctx
->user_bufs
)
7961 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7962 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7964 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
7965 unpin_user_page(imu
->bvec
[j
].bv_page
);
7967 if (imu
->acct_pages
)
7968 io_unaccount_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
7973 kfree(ctx
->user_bufs
);
7974 ctx
->user_bufs
= NULL
;
7975 ctx
->nr_user_bufs
= 0;
7979 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
7980 void __user
*arg
, unsigned index
)
7982 struct iovec __user
*src
;
7984 #ifdef CONFIG_COMPAT
7986 struct compat_iovec __user
*ciovs
;
7987 struct compat_iovec ciov
;
7989 ciovs
= (struct compat_iovec __user
*) arg
;
7990 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
7993 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
7994 dst
->iov_len
= ciov
.iov_len
;
7998 src
= (struct iovec __user
*) arg
;
7999 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
8005 * Not super efficient, but this is just a registration time. And we do cache
8006 * the last compound head, so generally we'll only do a full search if we don't
8009 * We check if the given compound head page has already been accounted, to
8010 * avoid double accounting it. This allows us to account the full size of the
8011 * page, not just the constituent pages of a huge page.
8013 static bool headpage_already_acct(struct io_ring_ctx
*ctx
, struct page
**pages
,
8014 int nr_pages
, struct page
*hpage
)
8018 /* check current page array */
8019 for (i
= 0; i
< nr_pages
; i
++) {
8020 if (!PageCompound(pages
[i
]))
8022 if (compound_head(pages
[i
]) == hpage
)
8026 /* check previously registered pages */
8027 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8028 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8030 for (j
= 0; j
< imu
->nr_bvecs
; j
++) {
8031 if (!PageCompound(imu
->bvec
[j
].bv_page
))
8033 if (compound_head(imu
->bvec
[j
].bv_page
) == hpage
)
8041 static int io_buffer_account_pin(struct io_ring_ctx
*ctx
, struct page
**pages
,
8042 int nr_pages
, struct io_mapped_ubuf
*imu
,
8043 struct page
**last_hpage
)
8047 for (i
= 0; i
< nr_pages
; i
++) {
8048 if (!PageCompound(pages
[i
])) {
8053 hpage
= compound_head(pages
[i
]);
8054 if (hpage
== *last_hpage
)
8056 *last_hpage
= hpage
;
8057 if (headpage_already_acct(ctx
, pages
, i
, hpage
))
8059 imu
->acct_pages
+= page_size(hpage
) >> PAGE_SHIFT
;
8063 if (!imu
->acct_pages
)
8066 ret
= io_account_mem(ctx
, imu
->acct_pages
, ACCT_PINNED
);
8068 imu
->acct_pages
= 0;
8072 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
8075 struct vm_area_struct
**vmas
= NULL
;
8076 struct page
**pages
= NULL
;
8077 struct page
*last_hpage
= NULL
;
8078 int i
, j
, got_pages
= 0;
8083 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
8086 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
8088 if (!ctx
->user_bufs
)
8091 for (i
= 0; i
< nr_args
; i
++) {
8092 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
8093 unsigned long off
, start
, end
, ubuf
;
8098 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
8103 * Don't impose further limits on the size and buffer
8104 * constraints here, we'll -EINVAL later when IO is
8105 * submitted if they are wrong.
8108 if (!iov
.iov_base
|| !iov
.iov_len
)
8111 /* arbitrary limit, but we need something */
8112 if (iov
.iov_len
> SZ_1G
)
8115 ubuf
= (unsigned long) iov
.iov_base
;
8116 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
8117 start
= ubuf
>> PAGE_SHIFT
;
8118 nr_pages
= end
- start
;
8121 if (!pages
|| nr_pages
> got_pages
) {
8124 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
8126 vmas
= kvmalloc_array(nr_pages
,
8127 sizeof(struct vm_area_struct
*),
8129 if (!pages
|| !vmas
) {
8133 got_pages
= nr_pages
;
8136 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
8143 mmap_read_lock(current
->mm
);
8144 pret
= pin_user_pages(ubuf
, nr_pages
,
8145 FOLL_WRITE
| FOLL_LONGTERM
,
8147 if (pret
== nr_pages
) {
8148 /* don't support file backed memory */
8149 for (j
= 0; j
< nr_pages
; j
++) {
8150 struct vm_area_struct
*vma
= vmas
[j
];
8153 !is_file_hugepages(vma
->vm_file
)) {
8159 ret
= pret
< 0 ? pret
: -EFAULT
;
8161 mmap_read_unlock(current
->mm
);
8164 * if we did partial map, or found file backed vmas,
8165 * release any pages we did get
8168 unpin_user_pages(pages
, pret
);
8173 ret
= io_buffer_account_pin(ctx
, pages
, pret
, imu
, &last_hpage
);
8175 unpin_user_pages(pages
, pret
);
8180 off
= ubuf
& ~PAGE_MASK
;
8182 for (j
= 0; j
< nr_pages
; j
++) {
8185 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
8186 imu
->bvec
[j
].bv_page
= pages
[j
];
8187 imu
->bvec
[j
].bv_len
= vec_len
;
8188 imu
->bvec
[j
].bv_offset
= off
;
8192 /* store original address for later verification */
8194 imu
->len
= iov
.iov_len
;
8195 imu
->nr_bvecs
= nr_pages
;
8197 ctx
->nr_user_bufs
++;
8205 io_sqe_buffer_unregister(ctx
);
8209 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
8211 __s32 __user
*fds
= arg
;
8217 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
8220 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
8221 if (IS_ERR(ctx
->cq_ev_fd
)) {
8222 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
8223 ctx
->cq_ev_fd
= NULL
;
8230 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
8232 if (ctx
->cq_ev_fd
) {
8233 eventfd_ctx_put(ctx
->cq_ev_fd
);
8234 ctx
->cq_ev_fd
= NULL
;
8241 static int __io_destroy_buffers(int id
, void *p
, void *data
)
8243 struct io_ring_ctx
*ctx
= data
;
8244 struct io_buffer
*buf
= p
;
8246 __io_remove_buffers(ctx
, buf
, id
, -1U);
8250 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
8252 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
8253 idr_destroy(&ctx
->io_buffer_idr
);
8256 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
8258 io_finish_async(ctx
);
8259 io_sqe_buffer_unregister(ctx
);
8261 if (ctx
->sqo_task
) {
8262 put_task_struct(ctx
->sqo_task
);
8263 ctx
->sqo_task
= NULL
;
8264 mmdrop(ctx
->mm_account
);
8265 ctx
->mm_account
= NULL
;
8268 #ifdef CONFIG_BLK_CGROUP
8269 if (ctx
->sqo_blkcg_css
)
8270 css_put(ctx
->sqo_blkcg_css
);
8273 io_sqe_files_unregister(ctx
);
8274 io_eventfd_unregister(ctx
);
8275 io_destroy_buffers(ctx
);
8276 idr_destroy(&ctx
->personality_idr
);
8278 #if defined(CONFIG_UNIX)
8279 if (ctx
->ring_sock
) {
8280 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
8281 sock_release(ctx
->ring_sock
);
8285 io_mem_free(ctx
->rings
);
8286 io_mem_free(ctx
->sq_sqes
);
8288 percpu_ref_exit(&ctx
->refs
);
8289 free_uid(ctx
->user
);
8290 put_cred(ctx
->creds
);
8291 kfree(ctx
->cancel_hash
);
8292 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
8296 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
8298 struct io_ring_ctx
*ctx
= file
->private_data
;
8301 poll_wait(file
, &ctx
->cq_wait
, wait
);
8303 * synchronizes with barrier from wq_has_sleeper call in
8307 if (!io_sqring_full(ctx
))
8308 mask
|= EPOLLOUT
| EPOLLWRNORM
;
8309 if (io_cqring_events(ctx
, false))
8310 mask
|= EPOLLIN
| EPOLLRDNORM
;
8315 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
8317 struct io_ring_ctx
*ctx
= file
->private_data
;
8319 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
8322 static int io_remove_personalities(int id
, void *p
, void *data
)
8324 struct io_ring_ctx
*ctx
= data
;
8325 struct io_identity
*iod
;
8327 iod
= idr_remove(&ctx
->personality_idr
, id
);
8329 put_cred(iod
->creds
);
8330 if (refcount_dec_and_test(&iod
->count
))
8336 static void io_ring_exit_work(struct work_struct
*work
)
8338 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
8342 * If we're doing polled IO and end up having requests being
8343 * submitted async (out-of-line), then completions can come in while
8344 * we're waiting for refs to drop. We need to reap these manually,
8345 * as nobody else will be looking for them.
8349 io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8350 io_iopoll_try_reap_events(ctx
);
8351 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
8352 io_ring_ctx_free(ctx
);
8355 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
8357 mutex_lock(&ctx
->uring_lock
);
8358 percpu_ref_kill(&ctx
->refs
);
8359 mutex_unlock(&ctx
->uring_lock
);
8361 io_kill_timeouts(ctx
, NULL
);
8362 io_poll_remove_all(ctx
, NULL
);
8365 io_wq_cancel_all(ctx
->io_wq
);
8367 /* if we failed setting up the ctx, we might not have any rings */
8369 io_cqring_overflow_flush(ctx
, true, NULL
, NULL
);
8370 io_iopoll_try_reap_events(ctx
);
8371 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
8374 * Do this upfront, so we won't have a grace period where the ring
8375 * is closed but resources aren't reaped yet. This can cause
8376 * spurious failure in setting up a new ring.
8378 io_unaccount_mem(ctx
, ring_pages(ctx
->sq_entries
, ctx
->cq_entries
),
8381 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
8383 * Use system_unbound_wq to avoid spawning tons of event kworkers
8384 * if we're exiting a ton of rings at the same time. It just adds
8385 * noise and overhead, there's no discernable change in runtime
8386 * over using system_wq.
8388 queue_work(system_unbound_wq
, &ctx
->exit_work
);
8391 static int io_uring_release(struct inode
*inode
, struct file
*file
)
8393 struct io_ring_ctx
*ctx
= file
->private_data
;
8395 file
->private_data
= NULL
;
8396 io_ring_ctx_wait_and_kill(ctx
);
8400 static bool io_wq_files_match(struct io_wq_work
*work
, void *data
)
8402 struct files_struct
*files
= data
;
8404 return !files
|| ((work
->flags
& IO_WQ_WORK_FILES
) &&
8405 work
->identity
->files
== files
);
8409 * Returns true if 'preq' is the link parent of 'req'
8411 static bool io_match_link(struct io_kiocb
*preq
, struct io_kiocb
*req
)
8413 struct io_kiocb
*link
;
8415 if (!(preq
->flags
& REQ_F_LINK_HEAD
))
8418 list_for_each_entry(link
, &preq
->link_list
, link_list
) {
8426 static bool io_match_link_files(struct io_kiocb
*req
,
8427 struct files_struct
*files
)
8429 struct io_kiocb
*link
;
8431 if (io_match_files(req
, files
))
8433 if (req
->flags
& REQ_F_LINK_HEAD
) {
8434 list_for_each_entry(link
, &req
->link_list
, link_list
) {
8435 if (io_match_files(link
, files
))
8443 * We're looking to cancel 'req' because it's holding on to our files, but
8444 * 'req' could be a link to another request. See if it is, and cancel that
8445 * parent request if so.
8447 static bool io_poll_remove_link(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
)
8449 struct hlist_node
*tmp
;
8450 struct io_kiocb
*preq
;
8454 spin_lock_irq(&ctx
->completion_lock
);
8455 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
8456 struct hlist_head
*list
;
8458 list
= &ctx
->cancel_hash
[i
];
8459 hlist_for_each_entry_safe(preq
, tmp
, list
, hash_node
) {
8460 found
= io_match_link(preq
, req
);
8462 io_poll_remove_one(preq
);
8467 spin_unlock_irq(&ctx
->completion_lock
);
8471 static bool io_timeout_remove_link(struct io_ring_ctx
*ctx
,
8472 struct io_kiocb
*req
)
8474 struct io_kiocb
*preq
;
8477 spin_lock_irq(&ctx
->completion_lock
);
8478 list_for_each_entry(preq
, &ctx
->timeout_list
, timeout
.list
) {
8479 found
= io_match_link(preq
, req
);
8481 __io_timeout_cancel(preq
);
8485 spin_unlock_irq(&ctx
->completion_lock
);
8489 static bool io_cancel_link_cb(struct io_wq_work
*work
, void *data
)
8491 return io_match_link(container_of(work
, struct io_kiocb
, work
), data
);
8494 static void io_attempt_cancel(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
)
8496 enum io_wq_cancel cret
;
8498 /* cancel this particular work, if it's running */
8499 cret
= io_wq_cancel_work(ctx
->io_wq
, &req
->work
);
8500 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8503 /* find links that hold this pending, cancel those */
8504 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_link_cb
, req
, true);
8505 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8508 /* if we have a poll link holding this pending, cancel that */
8509 if (io_poll_remove_link(ctx
, req
))
8512 /* final option, timeout link is holding this req pending */
8513 io_timeout_remove_link(ctx
, req
);
8516 static void io_cancel_defer_files(struct io_ring_ctx
*ctx
,
8517 struct files_struct
*files
)
8519 struct io_defer_entry
*de
= NULL
;
8522 spin_lock_irq(&ctx
->completion_lock
);
8523 list_for_each_entry_reverse(de
, &ctx
->defer_list
, list
) {
8524 if (io_match_link_files(de
->req
, files
)) {
8525 list_cut_position(&list
, &ctx
->defer_list
, &de
->list
);
8529 spin_unlock_irq(&ctx
->completion_lock
);
8531 while (!list_empty(&list
)) {
8532 de
= list_first_entry(&list
, struct io_defer_entry
, list
);
8533 list_del_init(&de
->list
);
8534 req_set_fail_links(de
->req
);
8535 io_put_req(de
->req
);
8536 io_req_complete(de
->req
, -ECANCELED
);
8542 * Returns true if we found and killed one or more files pinning requests
8544 static bool io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8545 struct files_struct
*files
)
8547 if (list_empty_careful(&ctx
->inflight_list
))
8550 io_cancel_defer_files(ctx
, files
);
8551 /* cancel all at once, should be faster than doing it one by one*/
8552 io_wq_cancel_cb(ctx
->io_wq
, io_wq_files_match
, files
, true);
8554 while (!list_empty_careful(&ctx
->inflight_list
)) {
8555 struct io_kiocb
*cancel_req
= NULL
, *req
;
8558 spin_lock_irq(&ctx
->inflight_lock
);
8559 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
8560 if (files
&& (req
->work
.flags
& IO_WQ_WORK_FILES
) &&
8561 req
->work
.identity
->files
!= files
)
8563 /* req is being completed, ignore */
8564 if (!refcount_inc_not_zero(&req
->refs
))
8570 prepare_to_wait(&ctx
->inflight_wait
, &wait
,
8571 TASK_UNINTERRUPTIBLE
);
8572 spin_unlock_irq(&ctx
->inflight_lock
);
8574 /* We need to keep going until we don't find a matching req */
8577 /* cancel this request, or head link requests */
8578 io_attempt_cancel(ctx
, cancel_req
);
8579 io_put_req(cancel_req
);
8580 /* cancellations _may_ trigger task work */
8583 finish_wait(&ctx
->inflight_wait
, &wait
);
8589 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8591 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8592 struct task_struct
*task
= data
;
8594 return io_task_match(req
, task
);
8597 static bool __io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8598 struct task_struct
*task
,
8599 struct files_struct
*files
)
8603 ret
= io_uring_cancel_files(ctx
, files
);
8605 enum io_wq_cancel cret
;
8607 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, task
, true);
8608 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8611 /* SQPOLL thread does its own polling */
8612 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8613 while (!list_empty_careful(&ctx
->iopoll_list
)) {
8614 io_iopoll_try_reap_events(ctx
);
8619 ret
|= io_poll_remove_all(ctx
, task
);
8620 ret
|= io_kill_timeouts(ctx
, task
);
8627 * We need to iteratively cancel requests, in case a request has dependent
8628 * hard links. These persist even for failure of cancelations, hence keep
8629 * looping until none are found.
8631 static void io_uring_cancel_task_requests(struct io_ring_ctx
*ctx
,
8632 struct files_struct
*files
)
8634 struct task_struct
*task
= current
;
8636 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) && ctx
->sq_data
)
8637 task
= ctx
->sq_data
->thread
;
8639 io_cqring_overflow_flush(ctx
, true, task
, files
);
8641 while (__io_uring_cancel_task_requests(ctx
, task
, files
)) {
8648 * Note that this task has used io_uring. We use it for cancelation purposes.
8650 static int io_uring_add_task_file(struct file
*file
)
8652 struct io_uring_task
*tctx
= current
->io_uring
;
8654 if (unlikely(!tctx
)) {
8657 ret
= io_uring_alloc_task_context(current
);
8660 tctx
= current
->io_uring
;
8662 if (tctx
->last
!= file
) {
8663 void *old
= xa_load(&tctx
->xa
, (unsigned long)file
);
8667 xa_store(&tctx
->xa
, (unsigned long)file
, file
, GFP_KERNEL
);
8676 * Remove this io_uring_file -> task mapping.
8678 static void io_uring_del_task_file(struct file
*file
)
8680 struct io_uring_task
*tctx
= current
->io_uring
;
8682 if (tctx
->last
== file
)
8684 file
= xa_erase(&tctx
->xa
, (unsigned long)file
);
8689 static void __io_uring_attempt_task_drop(struct file
*file
)
8691 struct file
*old
= xa_load(¤t
->io_uring
->xa
, (unsigned long)file
);
8694 io_uring_del_task_file(file
);
8698 * Drop task note for this file if we're the only ones that hold it after
8701 static void io_uring_attempt_task_drop(struct file
*file
, bool exiting
)
8703 if (!current
->io_uring
)
8706 * fput() is pending, will be 2 if the only other ref is our potential
8707 * task file note. If the task is exiting, drop regardless of count.
8709 if (!exiting
&& atomic_long_read(&file
->f_count
) != 2)
8712 __io_uring_attempt_task_drop(file
);
8715 void __io_uring_files_cancel(struct files_struct
*files
)
8717 struct io_uring_task
*tctx
= current
->io_uring
;
8719 unsigned long index
;
8721 /* make sure overflow events are dropped */
8722 tctx
->in_idle
= true;
8724 xa_for_each(&tctx
->xa
, index
, file
) {
8725 struct io_ring_ctx
*ctx
= file
->private_data
;
8727 io_uring_cancel_task_requests(ctx
, files
);
8729 io_uring_del_task_file(file
);
8734 * Find any io_uring fd that this task has registered or done IO on, and cancel
8737 void __io_uring_task_cancel(void)
8739 struct io_uring_task
*tctx
= current
->io_uring
;
8743 /* make sure overflow events are dropped */
8744 tctx
->in_idle
= true;
8747 /* read completions before cancelations */
8748 inflight
= percpu_counter_sum(&tctx
->inflight
);
8751 __io_uring_files_cancel(NULL
);
8753 prepare_to_wait(&tctx
->wait
, &wait
, TASK_UNINTERRUPTIBLE
);
8756 * If we've seen completions, retry. This avoids a race where
8757 * a completion comes in before we did prepare_to_wait().
8759 if (inflight
!= percpu_counter_sum(&tctx
->inflight
))
8764 finish_wait(&tctx
->wait
, &wait
);
8765 tctx
->in_idle
= false;
8768 static int io_uring_flush(struct file
*file
, void *data
)
8770 struct io_ring_ctx
*ctx
= file
->private_data
;
8773 * If the task is going away, cancel work it may have pending
8775 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
))
8778 io_uring_cancel_task_requests(ctx
, data
);
8779 io_uring_attempt_task_drop(file
, !data
);
8783 static void *io_uring_validate_mmap_request(struct file
*file
,
8784 loff_t pgoff
, size_t sz
)
8786 struct io_ring_ctx
*ctx
= file
->private_data
;
8787 loff_t offset
= pgoff
<< PAGE_SHIFT
;
8792 case IORING_OFF_SQ_RING
:
8793 case IORING_OFF_CQ_RING
:
8796 case IORING_OFF_SQES
:
8800 return ERR_PTR(-EINVAL
);
8803 page
= virt_to_head_page(ptr
);
8804 if (sz
> page_size(page
))
8805 return ERR_PTR(-EINVAL
);
8812 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
8814 size_t sz
= vma
->vm_end
- vma
->vm_start
;
8818 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
8820 return PTR_ERR(ptr
);
8822 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
8823 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
8826 #else /* !CONFIG_MMU */
8828 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
8830 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
8833 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
8835 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
8838 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
8839 unsigned long addr
, unsigned long len
,
8840 unsigned long pgoff
, unsigned long flags
)
8844 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
8846 return PTR_ERR(ptr
);
8848 return (unsigned long) ptr
;
8851 #endif /* !CONFIG_MMU */
8853 static void io_sqpoll_wait_sq(struct io_ring_ctx
*ctx
)
8858 if (!io_sqring_full(ctx
))
8861 prepare_to_wait(&ctx
->sqo_sq_wait
, &wait
, TASK_INTERRUPTIBLE
);
8863 if (!io_sqring_full(ctx
))
8867 } while (!signal_pending(current
));
8869 finish_wait(&ctx
->sqo_sq_wait
, &wait
);
8872 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
8873 u32
, min_complete
, u32
, flags
, const sigset_t __user
*, sig
,
8876 struct io_ring_ctx
*ctx
;
8883 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
|
8884 IORING_ENTER_SQ_WAIT
))
8892 if (f
.file
->f_op
!= &io_uring_fops
)
8896 ctx
= f
.file
->private_data
;
8897 if (!percpu_ref_tryget(&ctx
->refs
))
8901 if (ctx
->flags
& IORING_SETUP_R_DISABLED
)
8905 * For SQ polling, the thread will do all submissions and completions.
8906 * Just return the requested submit count, and wake the thread if
8910 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8911 if (!list_empty_careful(&ctx
->cq_overflow_list
))
8912 io_cqring_overflow_flush(ctx
, false, NULL
, NULL
);
8913 if (flags
& IORING_ENTER_SQ_WAKEUP
)
8914 wake_up(&ctx
->sq_data
->wait
);
8915 if (flags
& IORING_ENTER_SQ_WAIT
)
8916 io_sqpoll_wait_sq(ctx
);
8917 submitted
= to_submit
;
8918 } else if (to_submit
) {
8919 ret
= io_uring_add_task_file(f
.file
);
8922 mutex_lock(&ctx
->uring_lock
);
8923 submitted
= io_submit_sqes(ctx
, to_submit
);
8924 mutex_unlock(&ctx
->uring_lock
);
8926 if (submitted
!= to_submit
)
8929 if (flags
& IORING_ENTER_GETEVENTS
) {
8930 min_complete
= min(min_complete
, ctx
->cq_entries
);
8933 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
8934 * space applications don't need to do io completion events
8935 * polling again, they can rely on io_sq_thread to do polling
8936 * work, which can reduce cpu usage and uring_lock contention.
8938 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
8939 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8940 ret
= io_iopoll_check(ctx
, min_complete
);
8942 ret
= io_cqring_wait(ctx
, min_complete
, sig
, sigsz
);
8947 percpu_ref_put(&ctx
->refs
);
8950 return submitted
? submitted
: ret
;
8953 #ifdef CONFIG_PROC_FS
8954 static int io_uring_show_cred(int id
, void *p
, void *data
)
8956 const struct cred
*cred
= p
;
8957 struct seq_file
*m
= data
;
8958 struct user_namespace
*uns
= seq_user_ns(m
);
8959 struct group_info
*gi
;
8964 seq_printf(m
, "%5d\n", id
);
8965 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
8966 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
8967 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
8968 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
8969 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
8970 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
8971 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
8972 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
8973 seq_puts(m
, "\n\tGroups:\t");
8974 gi
= cred
->group_info
;
8975 for (g
= 0; g
< gi
->ngroups
; g
++) {
8976 seq_put_decimal_ull(m
, g
? " " : "",
8977 from_kgid_munged(uns
, gi
->gid
[g
]));
8979 seq_puts(m
, "\n\tCapEff:\t");
8980 cap
= cred
->cap_effective
;
8981 CAP_FOR_EACH_U32(__capi
)
8982 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
8987 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
8989 struct io_sq_data
*sq
= NULL
;
8994 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
8995 * since fdinfo case grabs it in the opposite direction of normal use
8996 * cases. If we fail to get the lock, we just don't iterate any
8997 * structures that could be going away outside the io_uring mutex.
8999 has_lock
= mutex_trylock(&ctx
->uring_lock
);
9001 if (has_lock
&& (ctx
->flags
& IORING_SETUP_SQPOLL
))
9004 seq_printf(m
, "SqThread:\t%d\n", sq
? task_pid_nr(sq
->thread
) : -1);
9005 seq_printf(m
, "SqThreadCpu:\t%d\n", sq
? task_cpu(sq
->thread
) : -1);
9006 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
9007 for (i
= 0; has_lock
&& i
< ctx
->nr_user_files
; i
++) {
9008 struct fixed_file_table
*table
;
9011 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
9012 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
9014 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
9016 seq_printf(m
, "%5u: <none>\n", i
);
9018 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
9019 for (i
= 0; has_lock
&& i
< ctx
->nr_user_bufs
; i
++) {
9020 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
9022 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
9023 (unsigned int) buf
->len
);
9025 if (has_lock
&& !idr_is_empty(&ctx
->personality_idr
)) {
9026 seq_printf(m
, "Personalities:\n");
9027 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
9029 seq_printf(m
, "PollList:\n");
9030 spin_lock_irq(&ctx
->completion_lock
);
9031 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
9032 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
9033 struct io_kiocb
*req
;
9035 hlist_for_each_entry(req
, list
, hash_node
)
9036 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
9037 req
->task
->task_works
!= NULL
);
9039 spin_unlock_irq(&ctx
->completion_lock
);
9041 mutex_unlock(&ctx
->uring_lock
);
9044 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
9046 struct io_ring_ctx
*ctx
= f
->private_data
;
9048 if (percpu_ref_tryget(&ctx
->refs
)) {
9049 __io_uring_show_fdinfo(ctx
, m
);
9050 percpu_ref_put(&ctx
->refs
);
9055 static const struct file_operations io_uring_fops
= {
9056 .release
= io_uring_release
,
9057 .flush
= io_uring_flush
,
9058 .mmap
= io_uring_mmap
,
9060 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
9061 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
9063 .poll
= io_uring_poll
,
9064 .fasync
= io_uring_fasync
,
9065 #ifdef CONFIG_PROC_FS
9066 .show_fdinfo
= io_uring_show_fdinfo
,
9070 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
9071 struct io_uring_params
*p
)
9073 struct io_rings
*rings
;
9074 size_t size
, sq_array_offset
;
9076 /* make sure these are sane, as we already accounted them */
9077 ctx
->sq_entries
= p
->sq_entries
;
9078 ctx
->cq_entries
= p
->cq_entries
;
9080 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
9081 if (size
== SIZE_MAX
)
9084 rings
= io_mem_alloc(size
);
9089 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
9090 rings
->sq_ring_mask
= p
->sq_entries
- 1;
9091 rings
->cq_ring_mask
= p
->cq_entries
- 1;
9092 rings
->sq_ring_entries
= p
->sq_entries
;
9093 rings
->cq_ring_entries
= p
->cq_entries
;
9094 ctx
->sq_mask
= rings
->sq_ring_mask
;
9095 ctx
->cq_mask
= rings
->cq_ring_mask
;
9097 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
9098 if (size
== SIZE_MAX
) {
9099 io_mem_free(ctx
->rings
);
9104 ctx
->sq_sqes
= io_mem_alloc(size
);
9105 if (!ctx
->sq_sqes
) {
9106 io_mem_free(ctx
->rings
);
9115 * Allocate an anonymous fd, this is what constitutes the application
9116 * visible backing of an io_uring instance. The application mmaps this
9117 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9118 * we have to tie this fd to a socket for file garbage collection purposes.
9120 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
9125 #if defined(CONFIG_UNIX)
9126 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
9132 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
9136 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
9137 O_RDWR
| O_CLOEXEC
);
9141 ret
= PTR_ERR(file
);
9145 #if defined(CONFIG_UNIX)
9146 ctx
->ring_sock
->file
= file
;
9148 if (unlikely(io_uring_add_task_file(file
))) {
9149 file
= ERR_PTR(-ENOMEM
);
9152 fd_install(ret
, file
);
9155 #if defined(CONFIG_UNIX)
9156 sock_release(ctx
->ring_sock
);
9157 ctx
->ring_sock
= NULL
;
9162 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
9163 struct io_uring_params __user
*params
)
9165 struct user_struct
*user
= NULL
;
9166 struct io_ring_ctx
*ctx
;
9172 if (entries
> IORING_MAX_ENTRIES
) {
9173 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9175 entries
= IORING_MAX_ENTRIES
;
9179 * Use twice as many entries for the CQ ring. It's possible for the
9180 * application to drive a higher depth than the size of the SQ ring,
9181 * since the sqes are only used at submission time. This allows for
9182 * some flexibility in overcommitting a bit. If the application has
9183 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9184 * of CQ ring entries manually.
9186 p
->sq_entries
= roundup_pow_of_two(entries
);
9187 if (p
->flags
& IORING_SETUP_CQSIZE
) {
9189 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9190 * to a power-of-two, if it isn't already. We do NOT impose
9191 * any cq vs sq ring sizing.
9193 if (p
->cq_entries
< p
->sq_entries
)
9195 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
9196 if (!(p
->flags
& IORING_SETUP_CLAMP
))
9198 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
9200 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
9202 p
->cq_entries
= 2 * p
->sq_entries
;
9205 user
= get_uid(current_user());
9206 limit_mem
= !capable(CAP_IPC_LOCK
);
9209 ret
= __io_account_mem(user
,
9210 ring_pages(p
->sq_entries
, p
->cq_entries
));
9217 ctx
= io_ring_ctx_alloc(p
);
9220 __io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
9225 ctx
->compat
= in_compat_syscall();
9227 ctx
->creds
= get_current_cred();
9229 ctx
->loginuid
= current
->loginuid
;
9230 ctx
->sessionid
= current
->sessionid
;
9232 ctx
->sqo_task
= get_task_struct(current
);
9235 * This is just grabbed for accounting purposes. When a process exits,
9236 * the mm is exited and dropped before the files, hence we need to hang
9237 * on to this mm purely for the purposes of being able to unaccount
9238 * memory (locked/pinned vm). It's not used for anything else.
9240 mmgrab(current
->mm
);
9241 ctx
->mm_account
= current
->mm
;
9243 #ifdef CONFIG_BLK_CGROUP
9245 * The sq thread will belong to the original cgroup it was inited in.
9246 * If the cgroup goes offline (e.g. disabling the io controller), then
9247 * issued bios will be associated with the closest cgroup later in the
9251 ctx
->sqo_blkcg_css
= blkcg_css();
9252 ret
= css_tryget_online(ctx
->sqo_blkcg_css
);
9255 /* don't init against a dying cgroup, have the user try again */
9256 ctx
->sqo_blkcg_css
= NULL
;
9263 * Account memory _before_ installing the file descriptor. Once
9264 * the descriptor is installed, it can get closed at any time. Also
9265 * do this before hitting the general error path, as ring freeing
9266 * will un-account as well.
9268 io_account_mem(ctx
, ring_pages(p
->sq_entries
, p
->cq_entries
),
9270 ctx
->limit_mem
= limit_mem
;
9272 ret
= io_allocate_scq_urings(ctx
, p
);
9276 ret
= io_sq_offload_create(ctx
, p
);
9280 if (!(p
->flags
& IORING_SETUP_R_DISABLED
))
9281 io_sq_offload_start(ctx
);
9283 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
9284 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
9285 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
9286 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
9287 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
9288 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
9289 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
9290 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
9292 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
9293 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
9294 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
9295 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
9296 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
9297 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
9298 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
9299 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
9301 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
9302 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
9303 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
9304 IORING_FEAT_POLL_32BITS
;
9306 if (copy_to_user(params
, p
, sizeof(*p
))) {
9312 * Install ring fd as the very last thing, so we don't risk someone
9313 * having closed it before we finish setup
9315 ret
= io_uring_get_fd(ctx
);
9319 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
9322 io_ring_ctx_wait_and_kill(ctx
);
9327 * Sets up an aio uring context, and returns the fd. Applications asks for a
9328 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9329 * params structure passed in.
9331 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
9333 struct io_uring_params p
;
9336 if (copy_from_user(&p
, params
, sizeof(p
)))
9338 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
9343 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
9344 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
9345 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
|
9346 IORING_SETUP_R_DISABLED
))
9349 return io_uring_create(entries
, &p
, params
);
9352 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
9353 struct io_uring_params __user
*, params
)
9355 return io_uring_setup(entries
, params
);
9358 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
9360 struct io_uring_probe
*p
;
9364 size
= struct_size(p
, ops
, nr_args
);
9365 if (size
== SIZE_MAX
)
9367 p
= kzalloc(size
, GFP_KERNEL
);
9372 if (copy_from_user(p
, arg
, size
))
9375 if (memchr_inv(p
, 0, size
))
9378 p
->last_op
= IORING_OP_LAST
- 1;
9379 if (nr_args
> IORING_OP_LAST
)
9380 nr_args
= IORING_OP_LAST
;
9382 for (i
= 0; i
< nr_args
; i
++) {
9384 if (!io_op_defs
[i
].not_supported
)
9385 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
9390 if (copy_to_user(arg
, p
, size
))
9397 static int io_register_personality(struct io_ring_ctx
*ctx
)
9399 struct io_identity
*id
;
9402 id
= kmalloc(sizeof(*id
), GFP_KERNEL
);
9406 io_init_identity(id
);
9407 id
->creds
= get_current_cred();
9409 ret
= idr_alloc_cyclic(&ctx
->personality_idr
, id
, 1, USHRT_MAX
, GFP_KERNEL
);
9411 put_cred(id
->creds
);
9417 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
9419 struct io_identity
*iod
;
9421 iod
= idr_remove(&ctx
->personality_idr
, id
);
9423 put_cred(iod
->creds
);
9424 if (refcount_dec_and_test(&iod
->count
))
9432 static int io_register_restrictions(struct io_ring_ctx
*ctx
, void __user
*arg
,
9433 unsigned int nr_args
)
9435 struct io_uring_restriction
*res
;
9439 /* Restrictions allowed only if rings started disabled */
9440 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9443 /* We allow only a single restrictions registration */
9444 if (ctx
->restrictions
.registered
)
9447 if (!arg
|| nr_args
> IORING_MAX_RESTRICTIONS
)
9450 size
= array_size(nr_args
, sizeof(*res
));
9451 if (size
== SIZE_MAX
)
9454 res
= memdup_user(arg
, size
);
9456 return PTR_ERR(res
);
9460 for (i
= 0; i
< nr_args
; i
++) {
9461 switch (res
[i
].opcode
) {
9462 case IORING_RESTRICTION_REGISTER_OP
:
9463 if (res
[i
].register_op
>= IORING_REGISTER_LAST
) {
9468 __set_bit(res
[i
].register_op
,
9469 ctx
->restrictions
.register_op
);
9471 case IORING_RESTRICTION_SQE_OP
:
9472 if (res
[i
].sqe_op
>= IORING_OP_LAST
) {
9477 __set_bit(res
[i
].sqe_op
, ctx
->restrictions
.sqe_op
);
9479 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED
:
9480 ctx
->restrictions
.sqe_flags_allowed
= res
[i
].sqe_flags
;
9482 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED
:
9483 ctx
->restrictions
.sqe_flags_required
= res
[i
].sqe_flags
;
9492 /* Reset all restrictions if an error happened */
9494 memset(&ctx
->restrictions
, 0, sizeof(ctx
->restrictions
));
9496 ctx
->restrictions
.registered
= true;
9502 static int io_register_enable_rings(struct io_ring_ctx
*ctx
)
9504 if (!(ctx
->flags
& IORING_SETUP_R_DISABLED
))
9507 if (ctx
->restrictions
.registered
)
9508 ctx
->restricted
= 1;
9510 ctx
->flags
&= ~IORING_SETUP_R_DISABLED
;
9512 io_sq_offload_start(ctx
);
9517 static bool io_register_op_must_quiesce(int op
)
9520 case IORING_UNREGISTER_FILES
:
9521 case IORING_REGISTER_FILES_UPDATE
:
9522 case IORING_REGISTER_PROBE
:
9523 case IORING_REGISTER_PERSONALITY
:
9524 case IORING_UNREGISTER_PERSONALITY
:
9531 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
9532 void __user
*arg
, unsigned nr_args
)
9533 __releases(ctx
->uring_lock
)
9534 __acquires(ctx
->uring_lock
)
9539 * We're inside the ring mutex, if the ref is already dying, then
9540 * someone else killed the ctx or is already going through
9541 * io_uring_register().
9543 if (percpu_ref_is_dying(&ctx
->refs
))
9546 if (io_register_op_must_quiesce(opcode
)) {
9547 percpu_ref_kill(&ctx
->refs
);
9550 * Drop uring mutex before waiting for references to exit. If
9551 * another thread is currently inside io_uring_enter() it might
9552 * need to grab the uring_lock to make progress. If we hold it
9553 * here across the drain wait, then we can deadlock. It's safe
9554 * to drop the mutex here, since no new references will come in
9555 * after we've killed the percpu ref.
9557 mutex_unlock(&ctx
->uring_lock
);
9559 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
9562 ret
= io_run_task_work_sig();
9567 mutex_lock(&ctx
->uring_lock
);
9570 percpu_ref_resurrect(&ctx
->refs
);
9575 if (ctx
->restricted
) {
9576 if (opcode
>= IORING_REGISTER_LAST
) {
9581 if (!test_bit(opcode
, ctx
->restrictions
.register_op
)) {
9588 case IORING_REGISTER_BUFFERS
:
9589 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
9591 case IORING_UNREGISTER_BUFFERS
:
9595 ret
= io_sqe_buffer_unregister(ctx
);
9597 case IORING_REGISTER_FILES
:
9598 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
9600 case IORING_UNREGISTER_FILES
:
9604 ret
= io_sqe_files_unregister(ctx
);
9606 case IORING_REGISTER_FILES_UPDATE
:
9607 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
9609 case IORING_REGISTER_EVENTFD
:
9610 case IORING_REGISTER_EVENTFD_ASYNC
:
9614 ret
= io_eventfd_register(ctx
, arg
);
9617 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
9618 ctx
->eventfd_async
= 1;
9620 ctx
->eventfd_async
= 0;
9622 case IORING_UNREGISTER_EVENTFD
:
9626 ret
= io_eventfd_unregister(ctx
);
9628 case IORING_REGISTER_PROBE
:
9630 if (!arg
|| nr_args
> 256)
9632 ret
= io_probe(ctx
, arg
, nr_args
);
9634 case IORING_REGISTER_PERSONALITY
:
9638 ret
= io_register_personality(ctx
);
9640 case IORING_UNREGISTER_PERSONALITY
:
9644 ret
= io_unregister_personality(ctx
, nr_args
);
9646 case IORING_REGISTER_ENABLE_RINGS
:
9650 ret
= io_register_enable_rings(ctx
);
9652 case IORING_REGISTER_RESTRICTIONS
:
9653 ret
= io_register_restrictions(ctx
, arg
, nr_args
);
9661 if (io_register_op_must_quiesce(opcode
)) {
9662 /* bring the ctx back to life */
9663 percpu_ref_reinit(&ctx
->refs
);
9665 reinit_completion(&ctx
->ref_comp
);
9670 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
9671 void __user
*, arg
, unsigned int, nr_args
)
9673 struct io_ring_ctx
*ctx
;
9682 if (f
.file
->f_op
!= &io_uring_fops
)
9685 ctx
= f
.file
->private_data
;
9687 mutex_lock(&ctx
->uring_lock
);
9688 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
9689 mutex_unlock(&ctx
->uring_lock
);
9690 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
9691 ctx
->cq_ev_fd
!= NULL
, ret
);
9697 static int __init
io_uring_init(void)
9699 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
9700 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
9701 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
9704 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
9705 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
9706 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
9707 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
9708 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
9709 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
9710 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
9711 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
9712 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
9713 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
9714 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
9715 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
9716 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
9717 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
9718 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
9719 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
9720 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
9721 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
9722 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
9723 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
9724 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
9725 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
9726 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
9727 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
9728 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
9729 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
9730 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
9731 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
9732 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
9733 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
9734 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
9736 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
9737 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
9738 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
9741 __initcall(io_uring_init
);