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/mmu_context.h>
59 #include <linux/percpu.h>
60 #include <linux/slab.h>
61 #include <linux/kthread.h>
62 #include <linux/blkdev.h>
63 #include <linux/bvec.h>
64 #include <linux/net.h>
66 #include <net/af_unix.h>
68 #include <linux/anon_inodes.h>
69 #include <linux/sched/mm.h>
70 #include <linux/uaccess.h>
71 #include <linux/nospec.h>
72 #include <linux/sizes.h>
73 #include <linux/hugetlb.h>
74 #include <linux/highmem.h>
75 #include <linux/namei.h>
76 #include <linux/fsnotify.h>
77 #include <linux/fadvise.h>
78 #include <linux/eventpoll.h>
79 #include <linux/fs_struct.h>
80 #include <linux/splice.h>
81 #include <linux/task_work.h>
83 #define CREATE_TRACE_POINTS
84 #include <trace/events/io_uring.h>
86 #include <uapi/linux/io_uring.h>
91 #define IORING_MAX_ENTRIES 32768
92 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
95 * Shift of 9 is 512 entries, or exactly one page on 64-bit archs
97 #define IORING_FILE_TABLE_SHIFT 9
98 #define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT)
99 #define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1)
100 #define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE)
103 u32 head ____cacheline_aligned_in_smp
;
104 u32 tail ____cacheline_aligned_in_smp
;
108 * This data is shared with the application through the mmap at offsets
109 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
111 * The offsets to the member fields are published through struct
112 * io_sqring_offsets when calling io_uring_setup.
116 * Head and tail offsets into the ring; the offsets need to be
117 * masked to get valid indices.
119 * The kernel controls head of the sq ring and the tail of the cq ring,
120 * and the application controls tail of the sq ring and the head of the
123 struct io_uring sq
, cq
;
125 * Bitmasks to apply to head and tail offsets (constant, equals
128 u32 sq_ring_mask
, cq_ring_mask
;
129 /* Ring sizes (constant, power of 2) */
130 u32 sq_ring_entries
, cq_ring_entries
;
132 * Number of invalid entries dropped by the kernel due to
133 * invalid index stored in array
135 * Written by the kernel, shouldn't be modified by the
136 * application (i.e. get number of "new events" by comparing to
139 * After a new SQ head value was read by the application this
140 * counter includes all submissions that were dropped reaching
141 * the new SQ head (and possibly more).
147 * Written by the kernel, shouldn't be modified by the
150 * The application needs a full memory barrier before checking
151 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
155 * Number of completion events lost because the queue was full;
156 * this should be avoided by the application by making sure
157 * there are not more requests pending than there is space in
158 * the completion queue.
160 * Written by the kernel, shouldn't be modified by the
161 * application (i.e. get number of "new events" by comparing to
164 * As completion events come in out of order this counter is not
165 * ordered with any other data.
169 * Ring buffer of completion events.
171 * The kernel writes completion events fresh every time they are
172 * produced, so the application is allowed to modify pending
175 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
178 struct io_mapped_ubuf
{
181 struct bio_vec
*bvec
;
182 unsigned int nr_bvecs
;
185 struct fixed_file_table
{
189 struct fixed_file_ref_node
{
190 struct percpu_ref refs
;
191 struct list_head node
;
192 struct list_head file_list
;
193 struct fixed_file_data
*file_data
;
194 struct work_struct work
;
197 struct fixed_file_data
{
198 struct fixed_file_table
*table
;
199 struct io_ring_ctx
*ctx
;
201 struct percpu_ref
*cur_refs
;
202 struct percpu_ref refs
;
203 struct completion done
;
204 struct list_head ref_list
;
209 struct list_head list
;
217 struct percpu_ref refs
;
218 } ____cacheline_aligned_in_smp
;
222 unsigned int compat
: 1;
223 unsigned int account_mem
: 1;
224 unsigned int cq_overflow_flushed
: 1;
225 unsigned int drain_next
: 1;
226 unsigned int eventfd_async
: 1;
229 * Ring buffer of indices into array of io_uring_sqe, which is
230 * mmapped by the application using the IORING_OFF_SQES offset.
232 * This indirection could e.g. be used to assign fixed
233 * io_uring_sqe entries to operations and only submit them to
234 * the queue when needed.
236 * The kernel modifies neither the indices array nor the entries
240 unsigned cached_sq_head
;
243 unsigned sq_thread_idle
;
244 unsigned cached_sq_dropped
;
245 atomic_t cached_cq_overflow
;
246 unsigned long sq_check_overflow
;
248 struct list_head defer_list
;
249 struct list_head timeout_list
;
250 struct list_head cq_overflow_list
;
252 wait_queue_head_t inflight_wait
;
253 struct io_uring_sqe
*sq_sqes
;
254 } ____cacheline_aligned_in_smp
;
256 struct io_rings
*rings
;
260 struct task_struct
*sqo_thread
; /* if using sq thread polling */
261 struct mm_struct
*sqo_mm
;
262 wait_queue_head_t sqo_wait
;
265 * If used, fixed file set. Writers must ensure that ->refs is dead,
266 * readers must ensure that ->refs is alive as long as the file* is
267 * used. Only updated through io_uring_register(2).
269 struct fixed_file_data
*file_data
;
270 unsigned nr_user_files
;
272 struct file
*ring_file
;
274 /* if used, fixed mapped user buffers */
275 unsigned nr_user_bufs
;
276 struct io_mapped_ubuf
*user_bufs
;
278 struct user_struct
*user
;
280 const struct cred
*creds
;
282 /* 0 is for ctx quiesce/reinit/free, 1 is for sqo_thread started */
283 struct completion
*completions
;
285 /* if all else fails... */
286 struct io_kiocb
*fallback_req
;
288 #if defined(CONFIG_UNIX)
289 struct socket
*ring_sock
;
292 struct idr io_buffer_idr
;
294 struct idr personality_idr
;
297 unsigned cached_cq_tail
;
300 atomic_t cq_timeouts
;
301 unsigned long cq_check_overflow
;
302 struct wait_queue_head cq_wait
;
303 struct fasync_struct
*cq_fasync
;
304 struct eventfd_ctx
*cq_ev_fd
;
305 } ____cacheline_aligned_in_smp
;
308 struct mutex uring_lock
;
309 wait_queue_head_t wait
;
310 } ____cacheline_aligned_in_smp
;
313 spinlock_t completion_lock
;
316 * ->poll_list is protected by the ctx->uring_lock for
317 * io_uring instances that don't use IORING_SETUP_SQPOLL.
318 * For SQPOLL, only the single threaded io_sq_thread() will
319 * manipulate the list, hence no extra locking is needed there.
321 struct list_head poll_list
;
322 struct hlist_head
*cancel_hash
;
323 unsigned cancel_hash_bits
;
324 bool poll_multi_file
;
326 spinlock_t inflight_lock
;
327 struct list_head inflight_list
;
328 } ____cacheline_aligned_in_smp
;
330 struct work_struct exit_work
;
334 * First field must be the file pointer in all the
335 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
337 struct io_poll_iocb
{
340 struct wait_queue_head
*head
;
346 struct wait_queue_entry wait
;
351 struct file
*put_file
;
355 struct io_timeout_data
{
356 struct io_kiocb
*req
;
357 struct hrtimer timer
;
358 struct timespec64 ts
;
359 enum hrtimer_mode mode
;
364 struct sockaddr __user
*addr
;
365 int __user
*addr_len
;
367 unsigned long nofile
;
391 /* NOTE: kiocb has the file as the first member, so don't do it here */
399 struct sockaddr __user
*addr
;
406 struct user_msghdr __user
*msg
;
412 struct io_buffer
*kbuf
;
421 struct filename
*filename
;
422 struct statx __user
*buffer
;
424 unsigned long nofile
;
427 struct io_files_update
{
453 struct epoll_event event
;
457 struct file
*file_out
;
458 struct file
*file_in
;
465 struct io_provide_buf
{
474 struct io_async_connect
{
475 struct sockaddr_storage address
;
478 struct io_async_msghdr
{
479 struct iovec fast_iov
[UIO_FASTIOV
];
481 struct sockaddr __user
*uaddr
;
483 struct sockaddr_storage addr
;
487 struct iovec fast_iov
[UIO_FASTIOV
];
493 struct io_async_ctx
{
495 struct io_async_rw rw
;
496 struct io_async_msghdr msg
;
497 struct io_async_connect connect
;
498 struct io_timeout_data timeout
;
503 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
504 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
505 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
506 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
507 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
508 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
516 REQ_F_IOPOLL_COMPLETED_BIT
,
517 REQ_F_LINK_TIMEOUT_BIT
,
521 REQ_F_TIMEOUT_NOSEQ_BIT
,
522 REQ_F_COMP_LOCKED_BIT
,
523 REQ_F_NEED_CLEANUP_BIT
,
526 REQ_F_BUFFER_SELECTED_BIT
,
527 REQ_F_NO_FILE_TABLE_BIT
,
529 /* not a real bit, just to check we're not overflowing the space */
535 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
536 /* drain existing IO first */
537 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
539 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
540 /* doesn't sever on completion < 0 */
541 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
543 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
544 /* IOSQE_BUFFER_SELECT */
545 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
548 REQ_F_LINK_HEAD
= BIT(REQ_F_LINK_HEAD_BIT
),
549 /* already grabbed next link */
550 REQ_F_LINK_NEXT
= BIT(REQ_F_LINK_NEXT_BIT
),
551 /* fail rest of links */
552 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
553 /* on inflight list */
554 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
555 /* read/write uses file position */
556 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
557 /* must not punt to workers */
558 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
559 /* polled IO has completed */
560 REQ_F_IOPOLL_COMPLETED
= BIT(REQ_F_IOPOLL_COMPLETED_BIT
),
561 /* has linked timeout */
562 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
563 /* timeout request */
564 REQ_F_TIMEOUT
= BIT(REQ_F_TIMEOUT_BIT
),
566 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
567 /* must be punted even for NONBLOCK */
568 REQ_F_MUST_PUNT
= BIT(REQ_F_MUST_PUNT_BIT
),
569 /* no timeout sequence */
570 REQ_F_TIMEOUT_NOSEQ
= BIT(REQ_F_TIMEOUT_NOSEQ_BIT
),
571 /* completion under lock */
572 REQ_F_COMP_LOCKED
= BIT(REQ_F_COMP_LOCKED_BIT
),
574 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
575 /* in overflow list */
576 REQ_F_OVERFLOW
= BIT(REQ_F_OVERFLOW_BIT
),
577 /* already went through poll handler */
578 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
579 /* buffer already selected */
580 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
581 /* doesn't need file table for this request */
582 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
586 struct io_poll_iocb poll
;
587 struct io_wq_work work
;
591 * NOTE! Each of the iocb union members has the file pointer
592 * as the first entry in their struct definition. So you can
593 * access the file pointer through any of the sub-structs,
594 * or directly as just 'ki_filp' in this struct.
600 struct io_poll_iocb poll
;
601 struct io_accept accept
;
603 struct io_cancel cancel
;
604 struct io_timeout timeout
;
605 struct io_connect connect
;
606 struct io_sr_msg sr_msg
;
608 struct io_close close
;
609 struct io_files_update files_update
;
610 struct io_fadvise fadvise
;
611 struct io_madvise madvise
;
612 struct io_epoll epoll
;
613 struct io_splice splice
;
614 struct io_provide_buf pbuf
;
617 struct io_async_ctx
*io
;
619 bool needs_fixed_file
;
622 struct io_ring_ctx
*ctx
;
623 struct list_head list
;
626 struct task_struct
*task
;
632 struct list_head link_list
;
634 struct list_head inflight_entry
;
636 struct percpu_ref
*fixed_file_refs
;
640 * Only commands that never go async can use the below fields,
641 * obviously. Right now only IORING_OP_POLL_ADD uses them, and
642 * async armed poll handlers for regular commands. The latter
643 * restore the work, if needed.
646 struct callback_head task_work
;
647 struct hlist_node hash_node
;
648 struct async_poll
*apoll
;
650 struct io_wq_work work
;
654 #define IO_PLUG_THRESHOLD 2
655 #define IO_IOPOLL_BATCH 8
657 struct io_submit_state
{
658 struct blk_plug plug
;
661 * io_kiocb alloc cache
663 void *reqs
[IO_IOPOLL_BATCH
];
664 unsigned int free_reqs
;
667 * File reference cache
671 unsigned int has_refs
;
672 unsigned int used_refs
;
673 unsigned int ios_left
;
677 /* needs req->io allocated for deferral/async */
678 unsigned async_ctx
: 1;
679 /* needs current->mm setup, does mm access */
680 unsigned needs_mm
: 1;
681 /* needs req->file assigned */
682 unsigned needs_file
: 1;
683 /* needs req->file assigned IFF fd is >= 0 */
684 unsigned fd_non_neg
: 1;
685 /* hash wq insertion if file is a regular file */
686 unsigned hash_reg_file
: 1;
687 /* unbound wq insertion if file is a non-regular file */
688 unsigned unbound_nonreg_file
: 1;
689 /* opcode is not supported by this kernel */
690 unsigned not_supported
: 1;
691 /* needs file table */
692 unsigned file_table
: 1;
694 unsigned needs_fs
: 1;
695 /* set if opcode supports polled "wait" */
697 unsigned pollout
: 1;
698 /* op supports buffer selection */
699 unsigned buffer_select
: 1;
702 static const struct io_op_def io_op_defs
[] = {
703 [IORING_OP_NOP
] = {},
704 [IORING_OP_READV
] = {
708 .unbound_nonreg_file
= 1,
712 [IORING_OP_WRITEV
] = {
717 .unbound_nonreg_file
= 1,
720 [IORING_OP_FSYNC
] = {
723 [IORING_OP_READ_FIXED
] = {
725 .unbound_nonreg_file
= 1,
728 [IORING_OP_WRITE_FIXED
] = {
731 .unbound_nonreg_file
= 1,
734 [IORING_OP_POLL_ADD
] = {
736 .unbound_nonreg_file
= 1,
738 [IORING_OP_POLL_REMOVE
] = {},
739 [IORING_OP_SYNC_FILE_RANGE
] = {
742 [IORING_OP_SENDMSG
] = {
746 .unbound_nonreg_file
= 1,
750 [IORING_OP_RECVMSG
] = {
754 .unbound_nonreg_file
= 1,
759 [IORING_OP_TIMEOUT
] = {
763 [IORING_OP_TIMEOUT_REMOVE
] = {},
764 [IORING_OP_ACCEPT
] = {
767 .unbound_nonreg_file
= 1,
771 [IORING_OP_ASYNC_CANCEL
] = {},
772 [IORING_OP_LINK_TIMEOUT
] = {
776 [IORING_OP_CONNECT
] = {
780 .unbound_nonreg_file
= 1,
783 [IORING_OP_FALLOCATE
] = {
786 [IORING_OP_OPENAT
] = {
792 [IORING_OP_CLOSE
] = {
796 [IORING_OP_FILES_UPDATE
] = {
800 [IORING_OP_STATX
] = {
810 .unbound_nonreg_file
= 1,
814 [IORING_OP_WRITE
] = {
817 .unbound_nonreg_file
= 1,
820 [IORING_OP_FADVISE
] = {
823 [IORING_OP_MADVISE
] = {
829 .unbound_nonreg_file
= 1,
835 .unbound_nonreg_file
= 1,
839 [IORING_OP_OPENAT2
] = {
845 [IORING_OP_EPOLL_CTL
] = {
846 .unbound_nonreg_file
= 1,
849 [IORING_OP_SPLICE
] = {
852 .unbound_nonreg_file
= 1,
854 [IORING_OP_PROVIDE_BUFFERS
] = {},
855 [IORING_OP_REMOVE_BUFFERS
] = {},
858 static void io_wq_submit_work(struct io_wq_work
**workptr
);
859 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
860 static void io_put_req(struct io_kiocb
*req
);
861 static void __io_double_put_req(struct io_kiocb
*req
);
862 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
863 static void io_queue_linked_timeout(struct io_kiocb
*req
);
864 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
865 struct io_uring_files_update
*ip
,
867 static int io_grab_files(struct io_kiocb
*req
);
868 static void io_cleanup_req(struct io_kiocb
*req
);
869 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
870 int fd
, struct file
**out_file
, bool fixed
);
871 static void __io_queue_sqe(struct io_kiocb
*req
,
872 const struct io_uring_sqe
*sqe
);
874 static struct kmem_cache
*req_cachep
;
876 static const struct file_operations io_uring_fops
;
878 struct sock
*io_uring_get_socket(struct file
*file
)
880 #if defined(CONFIG_UNIX)
881 if (file
->f_op
== &io_uring_fops
) {
882 struct io_ring_ctx
*ctx
= file
->private_data
;
884 return ctx
->ring_sock
->sk
;
889 EXPORT_SYMBOL(io_uring_get_socket
);
891 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
893 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
895 complete(&ctx
->completions
[0]);
898 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
900 struct io_ring_ctx
*ctx
;
903 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
907 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
908 if (!ctx
->fallback_req
)
911 ctx
->completions
= kmalloc(2 * sizeof(struct completion
), GFP_KERNEL
);
912 if (!ctx
->completions
)
916 * Use 5 bits less than the max cq entries, that should give us around
917 * 32 entries per hash list if totally full and uniformly spread.
919 hash_bits
= ilog2(p
->cq_entries
);
923 ctx
->cancel_hash_bits
= hash_bits
;
924 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
926 if (!ctx
->cancel_hash
)
928 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
930 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
931 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
934 ctx
->flags
= p
->flags
;
935 init_waitqueue_head(&ctx
->cq_wait
);
936 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
937 init_completion(&ctx
->completions
[0]);
938 init_completion(&ctx
->completions
[1]);
939 idr_init(&ctx
->io_buffer_idr
);
940 idr_init(&ctx
->personality_idr
);
941 mutex_init(&ctx
->uring_lock
);
942 init_waitqueue_head(&ctx
->wait
);
943 spin_lock_init(&ctx
->completion_lock
);
944 INIT_LIST_HEAD(&ctx
->poll_list
);
945 INIT_LIST_HEAD(&ctx
->defer_list
);
946 INIT_LIST_HEAD(&ctx
->timeout_list
);
947 init_waitqueue_head(&ctx
->inflight_wait
);
948 spin_lock_init(&ctx
->inflight_lock
);
949 INIT_LIST_HEAD(&ctx
->inflight_list
);
952 if (ctx
->fallback_req
)
953 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
954 kfree(ctx
->completions
);
955 kfree(ctx
->cancel_hash
);
960 static inline bool __req_need_defer(struct io_kiocb
*req
)
962 struct io_ring_ctx
*ctx
= req
->ctx
;
964 return req
->sequence
!= ctx
->cached_cq_tail
965 + atomic_read(&ctx
->cached_cq_overflow
);
968 static inline bool req_need_defer(struct io_kiocb
*req
)
970 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
))
971 return __req_need_defer(req
);
976 static struct io_kiocb
*io_get_deferred_req(struct io_ring_ctx
*ctx
)
978 struct io_kiocb
*req
;
980 req
= list_first_entry_or_null(&ctx
->defer_list
, struct io_kiocb
, list
);
981 if (req
&& !req_need_defer(req
)) {
982 list_del_init(&req
->list
);
989 static struct io_kiocb
*io_get_timeout_req(struct io_ring_ctx
*ctx
)
991 struct io_kiocb
*req
;
993 req
= list_first_entry_or_null(&ctx
->timeout_list
, struct io_kiocb
, list
);
995 if (req
->flags
& REQ_F_TIMEOUT_NOSEQ
)
997 if (!__req_need_defer(req
)) {
998 list_del_init(&req
->list
);
1006 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1008 struct io_rings
*rings
= ctx
->rings
;
1010 /* order cqe stores with ring update */
1011 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1013 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1014 wake_up_interruptible(&ctx
->cq_wait
);
1015 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1019 static inline void io_req_work_grab_env(struct io_kiocb
*req
,
1020 const struct io_op_def
*def
)
1022 if (!req
->work
.mm
&& def
->needs_mm
) {
1023 mmgrab(current
->mm
);
1024 req
->work
.mm
= current
->mm
;
1026 if (!req
->work
.creds
)
1027 req
->work
.creds
= get_current_cred();
1028 if (!req
->work
.fs
&& def
->needs_fs
) {
1029 spin_lock(¤t
->fs
->lock
);
1030 if (!current
->fs
->in_exec
) {
1031 req
->work
.fs
= current
->fs
;
1032 req
->work
.fs
->users
++;
1034 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1036 spin_unlock(¤t
->fs
->lock
);
1038 if (!req
->work
.task_pid
)
1039 req
->work
.task_pid
= task_pid_vnr(current
);
1042 static inline void io_req_work_drop_env(struct io_kiocb
*req
)
1045 mmdrop(req
->work
.mm
);
1046 req
->work
.mm
= NULL
;
1048 if (req
->work
.creds
) {
1049 put_cred(req
->work
.creds
);
1050 req
->work
.creds
= NULL
;
1053 struct fs_struct
*fs
= req
->work
.fs
;
1055 spin_lock(&req
->work
.fs
->lock
);
1058 spin_unlock(&req
->work
.fs
->lock
);
1064 static inline void io_prep_async_work(struct io_kiocb
*req
,
1065 struct io_kiocb
**link
)
1067 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1069 if (req
->flags
& REQ_F_ISREG
) {
1070 if (def
->hash_reg_file
)
1071 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1073 if (def
->unbound_nonreg_file
)
1074 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1077 io_req_work_grab_env(req
, def
);
1079 *link
= io_prep_linked_timeout(req
);
1082 static inline void io_queue_async_work(struct io_kiocb
*req
)
1084 struct io_ring_ctx
*ctx
= req
->ctx
;
1085 struct io_kiocb
*link
;
1087 io_prep_async_work(req
, &link
);
1089 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1090 &req
->work
, req
->flags
);
1091 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1094 io_queue_linked_timeout(link
);
1097 static void io_kill_timeout(struct io_kiocb
*req
)
1101 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1103 atomic_inc(&req
->ctx
->cq_timeouts
);
1104 list_del_init(&req
->list
);
1105 req
->flags
|= REQ_F_COMP_LOCKED
;
1106 io_cqring_fill_event(req
, 0);
1111 static void io_kill_timeouts(struct io_ring_ctx
*ctx
)
1113 struct io_kiocb
*req
, *tmp
;
1115 spin_lock_irq(&ctx
->completion_lock
);
1116 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, list
)
1117 io_kill_timeout(req
);
1118 spin_unlock_irq(&ctx
->completion_lock
);
1121 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1123 struct io_kiocb
*req
;
1125 while ((req
= io_get_timeout_req(ctx
)) != NULL
)
1126 io_kill_timeout(req
);
1128 __io_commit_cqring(ctx
);
1130 while ((req
= io_get_deferred_req(ctx
)) != NULL
)
1131 io_queue_async_work(req
);
1134 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1136 struct io_rings
*rings
= ctx
->rings
;
1139 tail
= ctx
->cached_cq_tail
;
1141 * writes to the cq entry need to come after reading head; the
1142 * control dependency is enough as we're using WRITE_ONCE to
1145 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1148 ctx
->cached_cq_tail
++;
1149 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1152 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1156 if (!ctx
->eventfd_async
)
1158 return io_wq_current_is_worker();
1161 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1163 if (waitqueue_active(&ctx
->wait
))
1164 wake_up(&ctx
->wait
);
1165 if (waitqueue_active(&ctx
->sqo_wait
))
1166 wake_up(&ctx
->sqo_wait
);
1167 if (io_should_trigger_evfd(ctx
))
1168 eventfd_signal(ctx
->cq_ev_fd
, 1);
1171 /* Returns true if there are no backlogged entries after the flush */
1172 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1174 struct io_rings
*rings
= ctx
->rings
;
1175 struct io_uring_cqe
*cqe
;
1176 struct io_kiocb
*req
;
1177 unsigned long flags
;
1181 if (list_empty_careful(&ctx
->cq_overflow_list
))
1183 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1184 rings
->cq_ring_entries
))
1188 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1190 /* if force is set, the ring is going away. always drop after that */
1192 ctx
->cq_overflow_flushed
= 1;
1195 while (!list_empty(&ctx
->cq_overflow_list
)) {
1196 cqe
= io_get_cqring(ctx
);
1200 req
= list_first_entry(&ctx
->cq_overflow_list
, struct io_kiocb
,
1202 list_move(&req
->list
, &list
);
1203 req
->flags
&= ~REQ_F_OVERFLOW
;
1205 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1206 WRITE_ONCE(cqe
->res
, req
->result
);
1207 WRITE_ONCE(cqe
->flags
, req
->cflags
);
1209 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1210 atomic_inc_return(&ctx
->cached_cq_overflow
));
1214 io_commit_cqring(ctx
);
1216 clear_bit(0, &ctx
->sq_check_overflow
);
1217 clear_bit(0, &ctx
->cq_check_overflow
);
1219 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1220 io_cqring_ev_posted(ctx
);
1222 while (!list_empty(&list
)) {
1223 req
= list_first_entry(&list
, struct io_kiocb
, list
);
1224 list_del(&req
->list
);
1231 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1233 struct io_ring_ctx
*ctx
= req
->ctx
;
1234 struct io_uring_cqe
*cqe
;
1236 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1239 * If we can't get a cq entry, userspace overflowed the
1240 * submission (by quite a lot). Increment the overflow count in
1243 cqe
= io_get_cqring(ctx
);
1245 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1246 WRITE_ONCE(cqe
->res
, res
);
1247 WRITE_ONCE(cqe
->flags
, cflags
);
1248 } else if (ctx
->cq_overflow_flushed
) {
1249 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1250 atomic_inc_return(&ctx
->cached_cq_overflow
));
1252 if (list_empty(&ctx
->cq_overflow_list
)) {
1253 set_bit(0, &ctx
->sq_check_overflow
);
1254 set_bit(0, &ctx
->cq_check_overflow
);
1256 req
->flags
|= REQ_F_OVERFLOW
;
1257 refcount_inc(&req
->refs
);
1259 req
->cflags
= cflags
;
1260 list_add_tail(&req
->list
, &ctx
->cq_overflow_list
);
1264 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1266 __io_cqring_fill_event(req
, res
, 0);
1269 static void __io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1271 struct io_ring_ctx
*ctx
= req
->ctx
;
1272 unsigned long flags
;
1274 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1275 __io_cqring_fill_event(req
, res
, cflags
);
1276 io_commit_cqring(ctx
);
1277 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1279 io_cqring_ev_posted(ctx
);
1282 static void io_cqring_add_event(struct io_kiocb
*req
, long res
)
1284 __io_cqring_add_event(req
, res
, 0);
1287 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1289 return req
== (struct io_kiocb
*)
1290 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1293 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1295 struct io_kiocb
*req
;
1297 req
= ctx
->fallback_req
;
1298 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1304 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1305 struct io_submit_state
*state
)
1307 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1308 struct io_kiocb
*req
;
1311 req
= kmem_cache_alloc(req_cachep
, gfp
);
1314 } else if (!state
->free_reqs
) {
1318 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1319 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1322 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1323 * retry single alloc to be on the safe side.
1325 if (unlikely(ret
<= 0)) {
1326 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1327 if (!state
->reqs
[0])
1331 state
->free_reqs
= ret
- 1;
1332 req
= state
->reqs
[ret
- 1];
1335 req
= state
->reqs
[state
->free_reqs
];
1340 return io_get_fallback_req(ctx
);
1343 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1347 percpu_ref_put(req
->fixed_file_refs
);
1352 static void __io_req_aux_free(struct io_kiocb
*req
)
1354 if (req
->flags
& REQ_F_NEED_CLEANUP
)
1355 io_cleanup_req(req
);
1359 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1361 put_task_struct(req
->task
);
1363 io_req_work_drop_env(req
);
1366 static void __io_free_req(struct io_kiocb
*req
)
1368 __io_req_aux_free(req
);
1370 if (req
->flags
& REQ_F_INFLIGHT
) {
1371 struct io_ring_ctx
*ctx
= req
->ctx
;
1372 unsigned long flags
;
1374 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1375 list_del(&req
->inflight_entry
);
1376 if (waitqueue_active(&ctx
->inflight_wait
))
1377 wake_up(&ctx
->inflight_wait
);
1378 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1381 percpu_ref_put(&req
->ctx
->refs
);
1382 if (likely(!io_is_fallback_req(req
)))
1383 kmem_cache_free(req_cachep
, req
);
1385 clear_bit_unlock(0, (unsigned long *) &req
->ctx
->fallback_req
);
1389 void *reqs
[IO_IOPOLL_BATCH
];
1394 static void io_free_req_many(struct io_ring_ctx
*ctx
, struct req_batch
*rb
)
1398 if (rb
->need_iter
) {
1399 int i
, inflight
= 0;
1400 unsigned long flags
;
1402 for (i
= 0; i
< rb
->to_free
; i
++) {
1403 struct io_kiocb
*req
= rb
->reqs
[i
];
1405 if (req
->flags
& REQ_F_FIXED_FILE
) {
1407 percpu_ref_put(req
->fixed_file_refs
);
1409 if (req
->flags
& REQ_F_INFLIGHT
)
1411 __io_req_aux_free(req
);
1416 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1417 for (i
= 0; i
< rb
->to_free
; i
++) {
1418 struct io_kiocb
*req
= rb
->reqs
[i
];
1420 if (req
->flags
& REQ_F_INFLIGHT
) {
1421 list_del(&req
->inflight_entry
);
1426 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1428 if (waitqueue_active(&ctx
->inflight_wait
))
1429 wake_up(&ctx
->inflight_wait
);
1432 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
1433 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
1434 rb
->to_free
= rb
->need_iter
= 0;
1437 static bool io_link_cancel_timeout(struct io_kiocb
*req
)
1439 struct io_ring_ctx
*ctx
= req
->ctx
;
1442 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1444 io_cqring_fill_event(req
, -ECANCELED
);
1445 io_commit_cqring(ctx
);
1446 req
->flags
&= ~REQ_F_LINK_HEAD
;
1454 static void io_req_link_next(struct io_kiocb
*req
, struct io_kiocb
**nxtptr
)
1456 struct io_ring_ctx
*ctx
= req
->ctx
;
1457 bool wake_ev
= false;
1459 /* Already got next link */
1460 if (req
->flags
& REQ_F_LINK_NEXT
)
1464 * The list should never be empty when we are called here. But could
1465 * potentially happen if the chain is messed up, check to be on the
1468 while (!list_empty(&req
->link_list
)) {
1469 struct io_kiocb
*nxt
= list_first_entry(&req
->link_list
,
1470 struct io_kiocb
, link_list
);
1472 if (unlikely((req
->flags
& REQ_F_LINK_TIMEOUT
) &&
1473 (nxt
->flags
& REQ_F_TIMEOUT
))) {
1474 list_del_init(&nxt
->link_list
);
1475 wake_ev
|= io_link_cancel_timeout(nxt
);
1476 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1480 list_del_init(&req
->link_list
);
1481 if (!list_empty(&nxt
->link_list
))
1482 nxt
->flags
|= REQ_F_LINK_HEAD
;
1487 req
->flags
|= REQ_F_LINK_NEXT
;
1489 io_cqring_ev_posted(ctx
);
1493 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
1495 static void io_fail_links(struct io_kiocb
*req
)
1497 struct io_ring_ctx
*ctx
= req
->ctx
;
1498 unsigned long flags
;
1500 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1502 while (!list_empty(&req
->link_list
)) {
1503 struct io_kiocb
*link
= list_first_entry(&req
->link_list
,
1504 struct io_kiocb
, link_list
);
1506 list_del_init(&link
->link_list
);
1507 trace_io_uring_fail_link(req
, link
);
1509 if ((req
->flags
& REQ_F_LINK_TIMEOUT
) &&
1510 link
->opcode
== IORING_OP_LINK_TIMEOUT
) {
1511 io_link_cancel_timeout(link
);
1513 io_cqring_fill_event(link
, -ECANCELED
);
1514 __io_double_put_req(link
);
1516 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1519 io_commit_cqring(ctx
);
1520 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1521 io_cqring_ev_posted(ctx
);
1524 static void io_req_find_next(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
1526 if (likely(!(req
->flags
& REQ_F_LINK_HEAD
)))
1530 * If LINK is set, we have dependent requests in this chain. If we
1531 * didn't fail this request, queue the first one up, moving any other
1532 * dependencies to the next request. In case of failure, fail the rest
1535 if (req
->flags
& REQ_F_FAIL_LINK
) {
1537 } else if ((req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_COMP_LOCKED
)) ==
1538 REQ_F_LINK_TIMEOUT
) {
1539 struct io_ring_ctx
*ctx
= req
->ctx
;
1540 unsigned long flags
;
1543 * If this is a timeout link, we could be racing with the
1544 * timeout timer. Grab the completion lock for this case to
1545 * protect against that.
1547 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1548 io_req_link_next(req
, nxt
);
1549 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1551 io_req_link_next(req
, nxt
);
1555 static void io_free_req(struct io_kiocb
*req
)
1557 struct io_kiocb
*nxt
= NULL
;
1559 io_req_find_next(req
, &nxt
);
1563 io_queue_async_work(nxt
);
1566 static void io_link_work_cb(struct io_wq_work
**workptr
)
1568 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
1569 struct io_kiocb
*link
;
1571 link
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1572 io_queue_linked_timeout(link
);
1573 io_wq_submit_work(workptr
);
1576 static void io_wq_assign_next(struct io_wq_work
**workptr
, struct io_kiocb
*nxt
)
1578 struct io_kiocb
*link
;
1579 const struct io_op_def
*def
= &io_op_defs
[nxt
->opcode
];
1581 if ((nxt
->flags
& REQ_F_ISREG
) && def
->hash_reg_file
)
1582 io_wq_hash_work(&nxt
->work
, file_inode(nxt
->file
));
1584 *workptr
= &nxt
->work
;
1585 link
= io_prep_linked_timeout(nxt
);
1587 nxt
->work
.func
= io_link_work_cb
;
1591 * Drop reference to request, return next in chain (if there is one) if this
1592 * was the last reference to this request.
1594 __attribute__((nonnull
))
1595 static void io_put_req_find_next(struct io_kiocb
*req
, struct io_kiocb
**nxtptr
)
1597 if (refcount_dec_and_test(&req
->refs
)) {
1598 io_req_find_next(req
, nxtptr
);
1603 static void io_put_req(struct io_kiocb
*req
)
1605 if (refcount_dec_and_test(&req
->refs
))
1609 static void io_steal_work(struct io_kiocb
*req
,
1610 struct io_wq_work
**workptr
)
1613 * It's in an io-wq worker, so there always should be at least
1614 * one reference, which will be dropped in io_put_work() just
1615 * after the current handler returns.
1617 * It also means, that if the counter dropped to 1, then there is
1618 * no asynchronous users left, so it's safe to steal the next work.
1620 if (refcount_read(&req
->refs
) == 1) {
1621 struct io_kiocb
*nxt
= NULL
;
1623 io_req_find_next(req
, &nxt
);
1625 io_wq_assign_next(workptr
, nxt
);
1630 * Must only be used if we don't need to care about links, usually from
1631 * within the completion handling itself.
1633 static void __io_double_put_req(struct io_kiocb
*req
)
1635 /* drop both submit and complete references */
1636 if (refcount_sub_and_test(2, &req
->refs
))
1640 static void io_double_put_req(struct io_kiocb
*req
)
1642 /* drop both submit and complete references */
1643 if (refcount_sub_and_test(2, &req
->refs
))
1647 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
1649 struct io_rings
*rings
= ctx
->rings
;
1651 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1653 * noflush == true is from the waitqueue handler, just ensure
1654 * we wake up the task, and the next invocation will flush the
1655 * entries. We cannot safely to it from here.
1657 if (noflush
&& !list_empty(&ctx
->cq_overflow_list
))
1660 io_cqring_overflow_flush(ctx
, false);
1663 /* See comment at the top of this file */
1665 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
1668 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
1670 struct io_rings
*rings
= ctx
->rings
;
1672 /* make sure SQ entry isn't read before tail */
1673 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
1676 static inline bool io_req_multi_free(struct req_batch
*rb
, struct io_kiocb
*req
)
1678 if ((req
->flags
& REQ_F_LINK_HEAD
) || io_is_fallback_req(req
))
1681 if (!(req
->flags
& REQ_F_FIXED_FILE
) || req
->io
)
1684 rb
->reqs
[rb
->to_free
++] = req
;
1685 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
1686 io_free_req_many(req
->ctx
, rb
);
1690 static int io_put_kbuf(struct io_kiocb
*req
)
1692 struct io_buffer
*kbuf
;
1695 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
1696 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
1697 cflags
|= IORING_CQE_F_BUFFER
;
1704 * Find and free completed poll iocbs
1706 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1707 struct list_head
*done
)
1709 struct req_batch rb
;
1710 struct io_kiocb
*req
;
1712 rb
.to_free
= rb
.need_iter
= 0;
1713 while (!list_empty(done
)) {
1716 req
= list_first_entry(done
, struct io_kiocb
, list
);
1717 list_del(&req
->list
);
1719 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
1720 cflags
= io_put_kbuf(req
);
1722 __io_cqring_fill_event(req
, req
->result
, cflags
);
1725 if (refcount_dec_and_test(&req
->refs
) &&
1726 !io_req_multi_free(&rb
, req
))
1730 io_commit_cqring(ctx
);
1731 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
1732 io_cqring_ev_posted(ctx
);
1733 io_free_req_many(ctx
, &rb
);
1736 static void io_iopoll_queue(struct list_head
*again
)
1738 struct io_kiocb
*req
;
1741 req
= list_first_entry(again
, struct io_kiocb
, list
);
1742 list_del(&req
->list
);
1743 refcount_inc(&req
->refs
);
1744 io_queue_async_work(req
);
1745 } while (!list_empty(again
));
1748 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1751 struct io_kiocb
*req
, *tmp
;
1758 * Only spin for completions if we don't have multiple devices hanging
1759 * off our complete list, and we're under the requested amount.
1761 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
1764 list_for_each_entry_safe(req
, tmp
, &ctx
->poll_list
, list
) {
1765 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
1768 * Move completed and retryable entries to our local lists.
1769 * If we find a request that requires polling, break out
1770 * and complete those lists first, if we have entries there.
1772 if (req
->flags
& REQ_F_IOPOLL_COMPLETED
) {
1773 list_move_tail(&req
->list
, &done
);
1776 if (!list_empty(&done
))
1779 if (req
->result
== -EAGAIN
) {
1780 list_move_tail(&req
->list
, &again
);
1783 if (!list_empty(&again
))
1786 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
1795 if (!list_empty(&done
))
1796 io_iopoll_complete(ctx
, nr_events
, &done
);
1798 if (!list_empty(&again
))
1799 io_iopoll_queue(&again
);
1805 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
1806 * non-spinning poll check - we'll still enter the driver poll loop, but only
1807 * as a non-spinning completion check.
1809 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1812 while (!list_empty(&ctx
->poll_list
) && !need_resched()) {
1815 ret
= io_do_iopoll(ctx
, nr_events
, min
);
1818 if (!min
|| *nr_events
>= min
)
1826 * We can't just wait for polled events to come to us, we have to actively
1827 * find and complete them.
1829 static void io_iopoll_reap_events(struct io_ring_ctx
*ctx
)
1831 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
1834 mutex_lock(&ctx
->uring_lock
);
1835 while (!list_empty(&ctx
->poll_list
)) {
1836 unsigned int nr_events
= 0;
1838 io_iopoll_getevents(ctx
, &nr_events
, 1);
1841 * Ensure we allow local-to-the-cpu processing to take place,
1842 * in this case we need to ensure that we reap all events.
1846 mutex_unlock(&ctx
->uring_lock
);
1849 static int io_iopoll_check(struct io_ring_ctx
*ctx
, unsigned *nr_events
,
1852 int iters
= 0, ret
= 0;
1855 * We disallow the app entering submit/complete with polling, but we
1856 * still need to lock the ring to prevent racing with polled issue
1857 * that got punted to a workqueue.
1859 mutex_lock(&ctx
->uring_lock
);
1864 * Don't enter poll loop if we already have events pending.
1865 * If we do, we can potentially be spinning for commands that
1866 * already triggered a CQE (eg in error).
1868 if (io_cqring_events(ctx
, false))
1872 * If a submit got punted to a workqueue, we can have the
1873 * application entering polling for a command before it gets
1874 * issued. That app will hold the uring_lock for the duration
1875 * of the poll right here, so we need to take a breather every
1876 * now and then to ensure that the issue has a chance to add
1877 * the poll to the issued list. Otherwise we can spin here
1878 * forever, while the workqueue is stuck trying to acquire the
1881 if (!(++iters
& 7)) {
1882 mutex_unlock(&ctx
->uring_lock
);
1883 mutex_lock(&ctx
->uring_lock
);
1886 if (*nr_events
< min
)
1887 tmin
= min
- *nr_events
;
1889 ret
= io_iopoll_getevents(ctx
, nr_events
, tmin
);
1893 } while (min
&& !*nr_events
&& !need_resched());
1895 mutex_unlock(&ctx
->uring_lock
);
1899 static void kiocb_end_write(struct io_kiocb
*req
)
1902 * Tell lockdep we inherited freeze protection from submission
1905 if (req
->flags
& REQ_F_ISREG
) {
1906 struct inode
*inode
= file_inode(req
->file
);
1908 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
1910 file_end_write(req
->file
);
1913 static inline void req_set_fail_links(struct io_kiocb
*req
)
1915 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1916 req
->flags
|= REQ_F_FAIL_LINK
;
1919 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
)
1921 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
1924 if (kiocb
->ki_flags
& IOCB_WRITE
)
1925 kiocb_end_write(req
);
1927 if (res
!= req
->result
)
1928 req_set_fail_links(req
);
1929 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
1930 cflags
= io_put_kbuf(req
);
1931 __io_cqring_add_event(req
, res
, cflags
);
1934 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
1936 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
1938 io_complete_rw_common(kiocb
, res
);
1942 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
1944 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
1946 if (kiocb
->ki_flags
& IOCB_WRITE
)
1947 kiocb_end_write(req
);
1949 if (res
!= req
->result
)
1950 req_set_fail_links(req
);
1953 req
->flags
|= REQ_F_IOPOLL_COMPLETED
;
1957 * After the iocb has been issued, it's safe to be found on the poll list.
1958 * Adding the kiocb to the list AFTER submission ensures that we don't
1959 * find it from a io_iopoll_getevents() thread before the issuer is done
1960 * accessing the kiocb cookie.
1962 static void io_iopoll_req_issued(struct io_kiocb
*req
)
1964 struct io_ring_ctx
*ctx
= req
->ctx
;
1967 * Track whether we have multiple files in our lists. This will impact
1968 * how we do polling eventually, not spinning if we're on potentially
1969 * different devices.
1971 if (list_empty(&ctx
->poll_list
)) {
1972 ctx
->poll_multi_file
= false;
1973 } else if (!ctx
->poll_multi_file
) {
1974 struct io_kiocb
*list_req
;
1976 list_req
= list_first_entry(&ctx
->poll_list
, struct io_kiocb
,
1978 if (list_req
->file
!= req
->file
)
1979 ctx
->poll_multi_file
= true;
1983 * For fast devices, IO may have already completed. If it has, add
1984 * it to the front so we find it first.
1986 if (req
->flags
& REQ_F_IOPOLL_COMPLETED
)
1987 list_add(&req
->list
, &ctx
->poll_list
);
1989 list_add_tail(&req
->list
, &ctx
->poll_list
);
1991 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
1992 wq_has_sleeper(&ctx
->sqo_wait
))
1993 wake_up(&ctx
->sqo_wait
);
1996 static void io_file_put(struct io_submit_state
*state
)
1999 int diff
= state
->has_refs
- state
->used_refs
;
2002 fput_many(state
->file
, diff
);
2008 * Get as many references to a file as we have IOs left in this submission,
2009 * assuming most submissions are for one file, or at least that each file
2010 * has more than one submission.
2012 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2018 if (state
->fd
== fd
) {
2025 state
->file
= fget_many(fd
, state
->ios_left
);
2030 state
->has_refs
= state
->ios_left
;
2031 state
->used_refs
= 1;
2037 * If we tracked the file through the SCM inflight mechanism, we could support
2038 * any file. For now, just ensure that anything potentially problematic is done
2041 static bool io_file_supports_async(struct file
*file
, int rw
)
2043 umode_t mode
= file_inode(file
)->i_mode
;
2045 if (S_ISBLK(mode
) || S_ISCHR(mode
) || S_ISSOCK(mode
))
2047 if (S_ISREG(mode
) && file
->f_op
!= &io_uring_fops
)
2050 if (!(file
->f_mode
& FMODE_NOWAIT
))
2054 return file
->f_op
->read_iter
!= NULL
;
2056 return file
->f_op
->write_iter
!= NULL
;
2059 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2060 bool force_nonblock
)
2062 struct io_ring_ctx
*ctx
= req
->ctx
;
2063 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2067 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2068 req
->flags
|= REQ_F_ISREG
;
2070 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2071 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2072 req
->flags
|= REQ_F_CUR_POS
;
2073 kiocb
->ki_pos
= req
->file
->f_pos
;
2075 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2076 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2077 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2081 ioprio
= READ_ONCE(sqe
->ioprio
);
2083 ret
= ioprio_check_cap(ioprio
);
2087 kiocb
->ki_ioprio
= ioprio
;
2089 kiocb
->ki_ioprio
= get_current_ioprio();
2091 /* don't allow async punt if RWF_NOWAIT was requested */
2092 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) ||
2093 (req
->file
->f_flags
& O_NONBLOCK
))
2094 req
->flags
|= REQ_F_NOWAIT
;
2097 kiocb
->ki_flags
|= IOCB_NOWAIT
;
2099 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2100 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2101 !kiocb
->ki_filp
->f_op
->iopoll
)
2104 kiocb
->ki_flags
|= IOCB_HIPRI
;
2105 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2108 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2110 kiocb
->ki_complete
= io_complete_rw
;
2113 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2114 req
->rw
.len
= READ_ONCE(sqe
->len
);
2115 /* we own ->private, reuse it for the buffer index / buffer ID */
2116 req
->rw
.kiocb
.private = (void *) (unsigned long)
2117 READ_ONCE(sqe
->buf_index
);
2121 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2127 case -ERESTARTNOINTR
:
2128 case -ERESTARTNOHAND
:
2129 case -ERESTART_RESTARTBLOCK
:
2131 * We can't just restart the syscall, since previously
2132 * submitted sqes may already be in progress. Just fail this
2138 kiocb
->ki_complete(kiocb
, ret
, 0);
2142 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
)
2144 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2146 if (req
->flags
& REQ_F_CUR_POS
)
2147 req
->file
->f_pos
= kiocb
->ki_pos
;
2148 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2149 io_complete_rw(kiocb
, ret
, 0);
2151 io_rw_done(kiocb
, ret
);
2154 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2155 struct iov_iter
*iter
)
2157 struct io_ring_ctx
*ctx
= req
->ctx
;
2158 size_t len
= req
->rw
.len
;
2159 struct io_mapped_ubuf
*imu
;
2160 unsigned index
, buf_index
;
2164 /* attempt to use fixed buffers without having provided iovecs */
2165 if (unlikely(!ctx
->user_bufs
))
2168 buf_index
= (unsigned long) req
->rw
.kiocb
.private;
2169 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2172 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2173 imu
= &ctx
->user_bufs
[index
];
2174 buf_addr
= req
->rw
.addr
;
2177 if (buf_addr
+ len
< buf_addr
)
2179 /* not inside the mapped region */
2180 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2184 * May not be a start of buffer, set size appropriately
2185 * and advance us to the beginning.
2187 offset
= buf_addr
- imu
->ubuf
;
2188 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2192 * Don't use iov_iter_advance() here, as it's really slow for
2193 * using the latter parts of a big fixed buffer - it iterates
2194 * over each segment manually. We can cheat a bit here, because
2197 * 1) it's a BVEC iter, we set it up
2198 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2199 * first and last bvec
2201 * So just find our index, and adjust the iterator afterwards.
2202 * If the offset is within the first bvec (or the whole first
2203 * bvec, just use iov_iter_advance(). This makes it easier
2204 * since we can just skip the first segment, which may not
2205 * be PAGE_SIZE aligned.
2207 const struct bio_vec
*bvec
= imu
->bvec
;
2209 if (offset
<= bvec
->bv_len
) {
2210 iov_iter_advance(iter
, offset
);
2212 unsigned long seg_skip
;
2214 /* skip first vec */
2215 offset
-= bvec
->bv_len
;
2216 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2218 iter
->bvec
= bvec
+ seg_skip
;
2219 iter
->nr_segs
-= seg_skip
;
2220 iter
->count
-= bvec
->bv_len
+ offset
;
2221 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2228 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2231 mutex_unlock(&ctx
->uring_lock
);
2234 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2237 * "Normal" inline submissions always hold the uring_lock, since we
2238 * grab it from the system call. Same is true for the SQPOLL offload.
2239 * The only exception is when we've detached the request and issue it
2240 * from an async worker thread, grab the lock for that case.
2243 mutex_lock(&ctx
->uring_lock
);
2246 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2247 int bgid
, struct io_buffer
*kbuf
,
2250 struct io_buffer
*head
;
2252 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2255 io_ring_submit_lock(req
->ctx
, needs_lock
);
2257 lockdep_assert_held(&req
->ctx
->uring_lock
);
2259 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
2261 if (!list_empty(&head
->list
)) {
2262 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2264 list_del(&kbuf
->list
);
2267 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
2269 if (*len
> kbuf
->len
)
2272 kbuf
= ERR_PTR(-ENOBUFS
);
2275 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2280 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2283 struct io_buffer
*kbuf
;
2286 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2287 bgid
= (int) (unsigned long) req
->rw
.kiocb
.private;
2288 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2291 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2292 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2293 return u64_to_user_ptr(kbuf
->addr
);
2296 #ifdef CONFIG_COMPAT
2297 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2300 struct compat_iovec __user
*uiov
;
2301 compat_ssize_t clen
;
2305 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2306 if (!access_ok(uiov
, sizeof(*uiov
)))
2308 if (__get_user(clen
, &uiov
->iov_len
))
2314 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2316 return PTR_ERR(buf
);
2317 iov
[0].iov_base
= buf
;
2318 iov
[0].iov_len
= (compat_size_t
) len
;
2323 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2326 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2330 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
2333 len
= iov
[0].iov_len
;
2336 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2338 return PTR_ERR(buf
);
2339 iov
[0].iov_base
= buf
;
2340 iov
[0].iov_len
= len
;
2344 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2347 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2351 else if (req
->rw
.len
> 1)
2354 #ifdef CONFIG_COMPAT
2355 if (req
->ctx
->compat
)
2356 return io_compat_import(req
, iov
, needs_lock
);
2359 return __io_iov_buffer_select(req
, iov
, needs_lock
);
2362 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
2363 struct iovec
**iovec
, struct iov_iter
*iter
,
2366 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
2367 size_t sqe_len
= req
->rw
.len
;
2371 opcode
= req
->opcode
;
2372 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
2374 return io_import_fixed(req
, rw
, iter
);
2377 /* buffer index only valid with fixed read/write, or buffer select */
2378 if (req
->rw
.kiocb
.private && !(req
->flags
& REQ_F_BUFFER_SELECT
))
2381 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
2382 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2383 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
2386 return PTR_ERR(buf
);
2388 req
->rw
.len
= sqe_len
;
2391 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
2393 return ret
< 0 ? ret
: sqe_len
;
2397 struct io_async_rw
*iorw
= &req
->io
->rw
;
2400 iov_iter_init(iter
, rw
, *iovec
, iorw
->nr_segs
, iorw
->size
);
2401 if (iorw
->iov
== iorw
->fast_iov
)
2406 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2407 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
2409 ret
= (*iovec
)->iov_len
;
2410 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
2416 #ifdef CONFIG_COMPAT
2417 if (req
->ctx
->compat
)
2418 return compat_import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
,
2422 return import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
);
2426 * For files that don't have ->read_iter() and ->write_iter(), handle them
2427 * by looping over ->read() or ->write() manually.
2429 static ssize_t
loop_rw_iter(int rw
, struct file
*file
, struct kiocb
*kiocb
,
2430 struct iov_iter
*iter
)
2435 * Don't support polled IO through this interface, and we can't
2436 * support non-blocking either. For the latter, this just causes
2437 * the kiocb to be handled from an async context.
2439 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2441 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2444 while (iov_iter_count(iter
)) {
2448 if (!iov_iter_is_bvec(iter
)) {
2449 iovec
= iov_iter_iovec(iter
);
2451 /* fixed buffers import bvec */
2452 iovec
.iov_base
= kmap(iter
->bvec
->bv_page
)
2454 iovec
.iov_len
= min(iter
->count
,
2455 iter
->bvec
->bv_len
- iter
->iov_offset
);
2459 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
2460 iovec
.iov_len
, &kiocb
->ki_pos
);
2462 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
2463 iovec
.iov_len
, &kiocb
->ki_pos
);
2466 if (iov_iter_is_bvec(iter
))
2467 kunmap(iter
->bvec
->bv_page
);
2475 if (nr
!= iovec
.iov_len
)
2477 iov_iter_advance(iter
, nr
);
2483 static void io_req_map_rw(struct io_kiocb
*req
, ssize_t io_size
,
2484 struct iovec
*iovec
, struct iovec
*fast_iov
,
2485 struct iov_iter
*iter
)
2487 req
->io
->rw
.nr_segs
= iter
->nr_segs
;
2488 req
->io
->rw
.size
= io_size
;
2489 req
->io
->rw
.iov
= iovec
;
2490 if (!req
->io
->rw
.iov
) {
2491 req
->io
->rw
.iov
= req
->io
->rw
.fast_iov
;
2492 if (req
->io
->rw
.iov
!= fast_iov
)
2493 memcpy(req
->io
->rw
.iov
, fast_iov
,
2494 sizeof(struct iovec
) * iter
->nr_segs
);
2496 req
->flags
|= REQ_F_NEED_CLEANUP
;
2500 static inline int __io_alloc_async_ctx(struct io_kiocb
*req
)
2502 req
->io
= kmalloc(sizeof(*req
->io
), GFP_KERNEL
);
2503 return req
->io
== NULL
;
2506 static int io_alloc_async_ctx(struct io_kiocb
*req
)
2508 if (!io_op_defs
[req
->opcode
].async_ctx
)
2511 return __io_alloc_async_ctx(req
);
2514 static int io_setup_async_rw(struct io_kiocb
*req
, ssize_t io_size
,
2515 struct iovec
*iovec
, struct iovec
*fast_iov
,
2516 struct iov_iter
*iter
)
2518 if (!io_op_defs
[req
->opcode
].async_ctx
)
2521 if (__io_alloc_async_ctx(req
))
2524 io_req_map_rw(req
, io_size
, iovec
, fast_iov
, iter
);
2529 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2530 bool force_nonblock
)
2532 struct io_async_ctx
*io
;
2533 struct iov_iter iter
;
2536 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
2540 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
2543 /* either don't need iovec imported or already have it */
2544 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
2548 io
->rw
.iov
= io
->rw
.fast_iov
;
2550 ret
= io_import_iovec(READ
, req
, &io
->rw
.iov
, &iter
, !force_nonblock
);
2555 io_req_map_rw(req
, ret
, io
->rw
.iov
, io
->rw
.fast_iov
, &iter
);
2559 static int io_read(struct io_kiocb
*req
, bool force_nonblock
)
2561 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2562 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2563 struct iov_iter iter
;
2565 ssize_t io_size
, ret
;
2567 ret
= io_import_iovec(READ
, req
, &iovec
, &iter
, !force_nonblock
);
2571 /* Ensure we clear previously set non-block flag */
2572 if (!force_nonblock
)
2573 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
2577 if (req
->flags
& REQ_F_LINK_HEAD
)
2578 req
->result
= io_size
;
2581 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
2582 * we know to async punt it even if it was opened O_NONBLOCK
2584 if (force_nonblock
&& !io_file_supports_async(req
->file
, READ
))
2587 iov_count
= iov_iter_count(&iter
);
2588 ret
= rw_verify_area(READ
, req
->file
, &kiocb
->ki_pos
, iov_count
);
2592 if (req
->file
->f_op
->read_iter
)
2593 ret2
= call_read_iter(req
->file
, kiocb
, &iter
);
2595 ret2
= loop_rw_iter(READ
, req
->file
, kiocb
, &iter
);
2597 /* Catch -EAGAIN return for forced non-blocking submission */
2598 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
2599 kiocb_done(kiocb
, ret2
);
2602 ret
= io_setup_async_rw(req
, io_size
, iovec
,
2603 inline_vecs
, &iter
);
2606 /* any defer here is final, must blocking retry */
2607 if (!(req
->flags
& REQ_F_NOWAIT
) &&
2608 !file_can_poll(req
->file
))
2609 req
->flags
|= REQ_F_MUST_PUNT
;
2615 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2619 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2620 bool force_nonblock
)
2622 struct io_async_ctx
*io
;
2623 struct iov_iter iter
;
2626 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
2630 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
2633 req
->fsize
= rlimit(RLIMIT_FSIZE
);
2635 /* either don't need iovec imported or already have it */
2636 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
2640 io
->rw
.iov
= io
->rw
.fast_iov
;
2642 ret
= io_import_iovec(WRITE
, req
, &io
->rw
.iov
, &iter
, !force_nonblock
);
2647 io_req_map_rw(req
, ret
, io
->rw
.iov
, io
->rw
.fast_iov
, &iter
);
2651 static int io_write(struct io_kiocb
*req
, bool force_nonblock
)
2653 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2654 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2655 struct iov_iter iter
;
2657 ssize_t ret
, io_size
;
2659 ret
= io_import_iovec(WRITE
, req
, &iovec
, &iter
, !force_nonblock
);
2663 /* Ensure we clear previously set non-block flag */
2664 if (!force_nonblock
)
2665 req
->rw
.kiocb
.ki_flags
&= ~IOCB_NOWAIT
;
2669 if (req
->flags
& REQ_F_LINK_HEAD
)
2670 req
->result
= io_size
;
2673 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
2674 * we know to async punt it even if it was opened O_NONBLOCK
2676 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
2679 /* file path doesn't support NOWAIT for non-direct_IO */
2680 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
2681 (req
->flags
& REQ_F_ISREG
))
2684 iov_count
= iov_iter_count(&iter
);
2685 ret
= rw_verify_area(WRITE
, req
->file
, &kiocb
->ki_pos
, iov_count
);
2690 * Open-code file_start_write here to grab freeze protection,
2691 * which will be released by another thread in
2692 * io_complete_rw(). Fool lockdep by telling it the lock got
2693 * released so that it doesn't complain about the held lock when
2694 * we return to userspace.
2696 if (req
->flags
& REQ_F_ISREG
) {
2697 __sb_start_write(file_inode(req
->file
)->i_sb
,
2698 SB_FREEZE_WRITE
, true);
2699 __sb_writers_release(file_inode(req
->file
)->i_sb
,
2702 kiocb
->ki_flags
|= IOCB_WRITE
;
2704 if (!force_nonblock
)
2705 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= req
->fsize
;
2707 if (req
->file
->f_op
->write_iter
)
2708 ret2
= call_write_iter(req
->file
, kiocb
, &iter
);
2710 ret2
= loop_rw_iter(WRITE
, req
->file
, kiocb
, &iter
);
2712 if (!force_nonblock
)
2713 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= RLIM_INFINITY
;
2716 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
2717 * retry them without IOCB_NOWAIT.
2719 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
2721 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
2722 kiocb_done(kiocb
, ret2
);
2725 ret
= io_setup_async_rw(req
, io_size
, iovec
,
2726 inline_vecs
, &iter
);
2729 /* any defer here is final, must blocking retry */
2730 if (!file_can_poll(req
->file
))
2731 req
->flags
|= REQ_F_MUST_PUNT
;
2736 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2741 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2743 struct io_splice
* sp
= &req
->splice
;
2744 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
2747 if (req
->flags
& REQ_F_NEED_CLEANUP
)
2751 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
2752 sp
->off_out
= READ_ONCE(sqe
->off
);
2753 sp
->len
= READ_ONCE(sqe
->len
);
2754 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
2756 if (unlikely(sp
->flags
& ~valid_flags
))
2759 ret
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
), &sp
->file_in
,
2760 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
2763 req
->flags
|= REQ_F_NEED_CLEANUP
;
2765 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
))
2766 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
2771 static bool io_splice_punt(struct file
*file
, int rw
)
2773 if (get_pipe_info(file
))
2775 if (!io_file_supports_async(file
, rw
))
2777 return !(file
->f_flags
& O_NONBLOCK
);
2780 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
2782 struct io_splice
*sp
= &req
->splice
;
2783 struct file
*in
= sp
->file_in
;
2784 struct file
*out
= sp
->file_out
;
2785 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
2786 loff_t
*poff_in
, *poff_out
;
2789 if (force_nonblock
) {
2790 if (io_splice_punt(in
, READ
) || io_splice_punt(out
, WRITE
))
2792 flags
|= SPLICE_F_NONBLOCK
;
2795 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
2796 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
2797 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
2798 if (force_nonblock
&& ret
== -EAGAIN
)
2801 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
2802 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2804 io_cqring_add_event(req
, ret
);
2806 req_set_fail_links(req
);
2812 * IORING_OP_NOP just posts a completion event, nothing else.
2814 static int io_nop(struct io_kiocb
*req
)
2816 struct io_ring_ctx
*ctx
= req
->ctx
;
2818 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
2821 io_cqring_add_event(req
, 0);
2826 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2828 struct io_ring_ctx
*ctx
= req
->ctx
;
2833 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
2835 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
2838 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
2839 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
2842 req
->sync
.off
= READ_ONCE(sqe
->off
);
2843 req
->sync
.len
= READ_ONCE(sqe
->len
);
2847 static bool io_req_cancelled(struct io_kiocb
*req
)
2849 if (req
->work
.flags
& IO_WQ_WORK_CANCEL
) {
2850 req_set_fail_links(req
);
2851 io_cqring_add_event(req
, -ECANCELED
);
2859 static void __io_fsync(struct io_kiocb
*req
)
2861 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
2864 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
2865 end
> 0 ? end
: LLONG_MAX
,
2866 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
2868 req_set_fail_links(req
);
2869 io_cqring_add_event(req
, ret
);
2873 static void io_fsync_finish(struct io_wq_work
**workptr
)
2875 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
2877 if (io_req_cancelled(req
))
2880 io_steal_work(req
, workptr
);
2883 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
2885 /* fsync always requires a blocking context */
2886 if (force_nonblock
) {
2887 req
->work
.func
= io_fsync_finish
;
2894 static void __io_fallocate(struct io_kiocb
*req
)
2898 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= req
->fsize
;
2899 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
2901 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= RLIM_INFINITY
;
2903 req_set_fail_links(req
);
2904 io_cqring_add_event(req
, ret
);
2908 static void io_fallocate_finish(struct io_wq_work
**workptr
)
2910 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
2912 if (io_req_cancelled(req
))
2914 __io_fallocate(req
);
2915 io_steal_work(req
, workptr
);
2918 static int io_fallocate_prep(struct io_kiocb
*req
,
2919 const struct io_uring_sqe
*sqe
)
2921 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
2924 req
->sync
.off
= READ_ONCE(sqe
->off
);
2925 req
->sync
.len
= READ_ONCE(sqe
->addr
);
2926 req
->sync
.mode
= READ_ONCE(sqe
->len
);
2927 req
->fsize
= rlimit(RLIMIT_FSIZE
);
2931 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
2933 /* fallocate always requiring blocking context */
2934 if (force_nonblock
) {
2935 req
->work
.func
= io_fallocate_finish
;
2939 __io_fallocate(req
);
2943 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2945 const char __user
*fname
;
2948 if (sqe
->ioprio
|| sqe
->buf_index
)
2950 if (req
->flags
& REQ_F_FIXED_FILE
)
2952 if (req
->flags
& REQ_F_NEED_CLEANUP
)
2955 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
2956 req
->open
.how
.mode
= READ_ONCE(sqe
->len
);
2957 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
2958 req
->open
.how
.flags
= READ_ONCE(sqe
->open_flags
);
2959 if (force_o_largefile())
2960 req
->open
.how
.flags
|= O_LARGEFILE
;
2962 req
->open
.filename
= getname(fname
);
2963 if (IS_ERR(req
->open
.filename
)) {
2964 ret
= PTR_ERR(req
->open
.filename
);
2965 req
->open
.filename
= NULL
;
2969 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
2970 req
->flags
|= REQ_F_NEED_CLEANUP
;
2974 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2976 struct open_how __user
*how
;
2977 const char __user
*fname
;
2981 if (sqe
->ioprio
|| sqe
->buf_index
)
2983 if (req
->flags
& REQ_F_FIXED_FILE
)
2985 if (req
->flags
& REQ_F_NEED_CLEANUP
)
2988 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
2989 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
2990 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
2991 len
= READ_ONCE(sqe
->len
);
2993 if (len
< OPEN_HOW_SIZE_VER0
)
2996 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3001 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3002 req
->open
.how
.flags
|= O_LARGEFILE
;
3004 req
->open
.filename
= getname(fname
);
3005 if (IS_ERR(req
->open
.filename
)) {
3006 ret
= PTR_ERR(req
->open
.filename
);
3007 req
->open
.filename
= NULL
;
3011 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3012 req
->flags
|= REQ_F_NEED_CLEANUP
;
3016 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
3018 struct open_flags op
;
3025 ret
= build_open_flags(&req
->open
.how
, &op
);
3029 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3033 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3036 ret
= PTR_ERR(file
);
3038 fsnotify_open(file
);
3039 fd_install(ret
, file
);
3042 putname(req
->open
.filename
);
3043 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3045 req_set_fail_links(req
);
3046 io_cqring_add_event(req
, ret
);
3051 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
3053 req
->open
.how
= build_open_how(req
->open
.how
.flags
, req
->open
.how
.mode
);
3054 return io_openat2(req
, force_nonblock
);
3057 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3058 const struct io_uring_sqe
*sqe
)
3060 struct io_provide_buf
*p
= &req
->pbuf
;
3063 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3066 tmp
= READ_ONCE(sqe
->fd
);
3067 if (!tmp
|| tmp
> USHRT_MAX
)
3070 memset(p
, 0, sizeof(*p
));
3072 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3076 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3077 int bgid
, unsigned nbufs
)
3081 /* shouldn't happen */
3085 /* the head kbuf is the list itself */
3086 while (!list_empty(&buf
->list
)) {
3087 struct io_buffer
*nxt
;
3089 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3090 list_del(&nxt
->list
);
3097 idr_remove(&ctx
->io_buffer_idr
, bgid
);
3102 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
)
3104 struct io_provide_buf
*p
= &req
->pbuf
;
3105 struct io_ring_ctx
*ctx
= req
->ctx
;
3106 struct io_buffer
*head
;
3109 io_ring_submit_lock(ctx
, !force_nonblock
);
3111 lockdep_assert_held(&ctx
->uring_lock
);
3114 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3116 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3118 io_ring_submit_lock(ctx
, !force_nonblock
);
3120 req_set_fail_links(req
);
3121 io_cqring_add_event(req
, ret
);
3126 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3127 const struct io_uring_sqe
*sqe
)
3129 struct io_provide_buf
*p
= &req
->pbuf
;
3132 if (sqe
->ioprio
|| sqe
->rw_flags
)
3135 tmp
= READ_ONCE(sqe
->fd
);
3136 if (!tmp
|| tmp
> USHRT_MAX
)
3139 p
->addr
= READ_ONCE(sqe
->addr
);
3140 p
->len
= READ_ONCE(sqe
->len
);
3142 if (!access_ok(u64_to_user_ptr(p
->addr
), p
->len
))
3145 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3146 tmp
= READ_ONCE(sqe
->off
);
3147 if (tmp
> USHRT_MAX
)
3153 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3155 struct io_buffer
*buf
;
3156 u64 addr
= pbuf
->addr
;
3157 int i
, bid
= pbuf
->bid
;
3159 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3160 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3165 buf
->len
= pbuf
->len
;
3170 INIT_LIST_HEAD(&buf
->list
);
3173 list_add_tail(&buf
->list
, &(*head
)->list
);
3177 return i
? i
: -ENOMEM
;
3180 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
)
3182 struct io_provide_buf
*p
= &req
->pbuf
;
3183 struct io_ring_ctx
*ctx
= req
->ctx
;
3184 struct io_buffer
*head
, *list
;
3187 io_ring_submit_lock(ctx
, !force_nonblock
);
3189 lockdep_assert_held(&ctx
->uring_lock
);
3191 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3193 ret
= io_add_buffers(p
, &head
);
3198 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
3201 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
3206 io_ring_submit_unlock(ctx
, !force_nonblock
);
3208 req_set_fail_links(req
);
3209 io_cqring_add_event(req
, ret
);
3214 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
3215 const struct io_uring_sqe
*sqe
)
3217 #if defined(CONFIG_EPOLL)
3218 if (sqe
->ioprio
|| sqe
->buf_index
)
3221 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
3222 req
->epoll
.op
= READ_ONCE(sqe
->len
);
3223 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
3225 if (ep_op_has_event(req
->epoll
.op
)) {
3226 struct epoll_event __user
*ev
;
3228 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3229 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
3239 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
)
3241 #if defined(CONFIG_EPOLL)
3242 struct io_epoll
*ie
= &req
->epoll
;
3245 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
3246 if (force_nonblock
&& ret
== -EAGAIN
)
3250 req_set_fail_links(req
);
3251 io_cqring_add_event(req
, ret
);
3259 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3261 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3262 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
3265 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
3266 req
->madvise
.len
= READ_ONCE(sqe
->len
);
3267 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3274 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
3276 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3277 struct io_madvise
*ma
= &req
->madvise
;
3283 ret
= do_madvise(ma
->addr
, ma
->len
, ma
->advice
);
3285 req_set_fail_links(req
);
3286 io_cqring_add_event(req
, ret
);
3294 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3296 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
3299 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
3300 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
3301 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3305 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
3307 struct io_fadvise
*fa
= &req
->fadvise
;
3310 if (force_nonblock
) {
3311 switch (fa
->advice
) {
3312 case POSIX_FADV_NORMAL
:
3313 case POSIX_FADV_RANDOM
:
3314 case POSIX_FADV_SEQUENTIAL
:
3321 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
3323 req_set_fail_links(req
);
3324 io_cqring_add_event(req
, ret
);
3329 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3331 const char __user
*fname
;
3332 unsigned lookup_flags
;
3335 if (sqe
->ioprio
|| sqe
->buf_index
)
3337 if (req
->flags
& REQ_F_FIXED_FILE
)
3339 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3342 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3343 req
->open
.mask
= READ_ONCE(sqe
->len
);
3344 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3345 req
->open
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3346 req
->open
.how
.flags
= READ_ONCE(sqe
->statx_flags
);
3348 if (vfs_stat_set_lookup_flags(&lookup_flags
, req
->open
.how
.flags
))
3351 req
->open
.filename
= getname_flags(fname
, lookup_flags
, NULL
);
3352 if (IS_ERR(req
->open
.filename
)) {
3353 ret
= PTR_ERR(req
->open
.filename
);
3354 req
->open
.filename
= NULL
;
3358 req
->flags
|= REQ_F_NEED_CLEANUP
;
3362 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
3364 struct io_open
*ctx
= &req
->open
;
3365 unsigned lookup_flags
;
3370 if (force_nonblock
) {
3371 /* only need file table for an actual valid fd */
3372 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
3373 req
->flags
|= REQ_F_NO_FILE_TABLE
;
3377 if (vfs_stat_set_lookup_flags(&lookup_flags
, ctx
->how
.flags
))
3381 /* filename_lookup() drops it, keep a reference */
3382 ctx
->filename
->refcnt
++;
3384 ret
= filename_lookup(ctx
->dfd
, ctx
->filename
, lookup_flags
, &path
,
3389 ret
= vfs_getattr(&path
, &stat
, ctx
->mask
, ctx
->how
.flags
);
3391 if (retry_estale(ret
, lookup_flags
)) {
3392 lookup_flags
|= LOOKUP_REVAL
;
3396 ret
= cp_statx(&stat
, ctx
->buffer
);
3398 putname(ctx
->filename
);
3399 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3401 req_set_fail_links(req
);
3402 io_cqring_add_event(req
, ret
);
3407 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3410 * If we queue this for async, it must not be cancellable. That would
3411 * leave the 'file' in an undeterminate state.
3413 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
3415 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
3416 sqe
->rw_flags
|| sqe
->buf_index
)
3418 if (req
->flags
& REQ_F_FIXED_FILE
)
3421 req
->close
.fd
= READ_ONCE(sqe
->fd
);
3422 if (req
->file
->f_op
== &io_uring_fops
||
3423 req
->close
.fd
== req
->ctx
->ring_fd
)
3429 /* only called when __close_fd_get_file() is done */
3430 static void __io_close_finish(struct io_kiocb
*req
)
3434 ret
= filp_close(req
->close
.put_file
, req
->work
.files
);
3436 req_set_fail_links(req
);
3437 io_cqring_add_event(req
, ret
);
3438 fput(req
->close
.put_file
);
3442 static void io_close_finish(struct io_wq_work
**workptr
)
3444 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3446 /* not cancellable, don't do io_req_cancelled() */
3447 __io_close_finish(req
);
3448 io_steal_work(req
, workptr
);
3451 static int io_close(struct io_kiocb
*req
, bool force_nonblock
)
3455 req
->close
.put_file
= NULL
;
3456 ret
= __close_fd_get_file(req
->close
.fd
, &req
->close
.put_file
);
3460 /* if the file has a flush method, be safe and punt to async */
3461 if (req
->close
.put_file
->f_op
->flush
&& force_nonblock
) {
3462 /* submission ref will be dropped, take it for async */
3463 refcount_inc(&req
->refs
);
3465 req
->work
.func
= io_close_finish
;
3467 * Do manual async queue here to avoid grabbing files - we don't
3468 * need the files, and it'll cause io_close_finish() to close
3469 * the file again and cause a double CQE entry for this request
3471 io_queue_async_work(req
);
3476 * No ->flush(), safely close from here and just punt the
3477 * fput() to async context.
3479 __io_close_finish(req
);
3483 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3485 struct io_ring_ctx
*ctx
= req
->ctx
;
3490 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3492 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3495 req
->sync
.off
= READ_ONCE(sqe
->off
);
3496 req
->sync
.len
= READ_ONCE(sqe
->len
);
3497 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
3501 static void __io_sync_file_range(struct io_kiocb
*req
)
3505 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
3508 req_set_fail_links(req
);
3509 io_cqring_add_event(req
, ret
);
3514 static void io_sync_file_range_finish(struct io_wq_work
**workptr
)
3516 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3518 if (io_req_cancelled(req
))
3520 __io_sync_file_range(req
);
3521 io_put_req(req
); /* put submission ref */
3524 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
3526 /* sync_file_range always requires a blocking context */
3527 if (force_nonblock
) {
3528 req
->work
.func
= io_sync_file_range_finish
;
3532 __io_sync_file_range(req
);
3536 #if defined(CONFIG_NET)
3537 static int io_setup_async_msg(struct io_kiocb
*req
,
3538 struct io_async_msghdr
*kmsg
)
3542 if (io_alloc_async_ctx(req
)) {
3543 if (kmsg
->iov
!= kmsg
->fast_iov
)
3547 req
->flags
|= REQ_F_NEED_CLEANUP
;
3548 memcpy(&req
->io
->msg
, kmsg
, sizeof(*kmsg
));
3552 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3554 struct io_sr_msg
*sr
= &req
->sr_msg
;
3555 struct io_async_ctx
*io
= req
->io
;
3558 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
3559 sr
->msg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3560 sr
->len
= READ_ONCE(sqe
->len
);
3562 #ifdef CONFIG_COMPAT
3563 if (req
->ctx
->compat
)
3564 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
3567 if (!io
|| req
->opcode
== IORING_OP_SEND
)
3569 /* iovec is already imported */
3570 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3573 io
->msg
.iov
= io
->msg
.fast_iov
;
3574 ret
= sendmsg_copy_msghdr(&io
->msg
.msg
, sr
->msg
, sr
->msg_flags
,
3577 req
->flags
|= REQ_F_NEED_CLEANUP
;
3581 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
)
3583 struct io_async_msghdr
*kmsg
= NULL
;
3584 struct socket
*sock
;
3587 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3590 sock
= sock_from_file(req
->file
, &ret
);
3592 struct io_async_ctx io
;
3596 kmsg
= &req
->io
->msg
;
3597 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
3598 /* if iov is set, it's allocated already */
3600 kmsg
->iov
= kmsg
->fast_iov
;
3601 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
3603 struct io_sr_msg
*sr
= &req
->sr_msg
;
3606 kmsg
->msg
.msg_name
= &io
.msg
.addr
;
3608 io
.msg
.iov
= io
.msg
.fast_iov
;
3609 ret
= sendmsg_copy_msghdr(&io
.msg
.msg
, sr
->msg
,
3610 sr
->msg_flags
, &io
.msg
.iov
);
3615 flags
= req
->sr_msg
.msg_flags
;
3616 if (flags
& MSG_DONTWAIT
)
3617 req
->flags
|= REQ_F_NOWAIT
;
3618 else if (force_nonblock
)
3619 flags
|= MSG_DONTWAIT
;
3621 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
3622 if (force_nonblock
&& ret
== -EAGAIN
)
3623 return io_setup_async_msg(req
, kmsg
);
3624 if (ret
== -ERESTARTSYS
)
3628 if (kmsg
&& kmsg
->iov
!= kmsg
->fast_iov
)
3630 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3631 io_cqring_add_event(req
, ret
);
3633 req_set_fail_links(req
);
3638 static int io_send(struct io_kiocb
*req
, bool force_nonblock
)
3640 struct socket
*sock
;
3643 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3646 sock
= sock_from_file(req
->file
, &ret
);
3648 struct io_sr_msg
*sr
= &req
->sr_msg
;
3653 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
,
3658 msg
.msg_name
= NULL
;
3659 msg
.msg_control
= NULL
;
3660 msg
.msg_controllen
= 0;
3661 msg
.msg_namelen
= 0;
3663 flags
= req
->sr_msg
.msg_flags
;
3664 if (flags
& MSG_DONTWAIT
)
3665 req
->flags
|= REQ_F_NOWAIT
;
3666 else if (force_nonblock
)
3667 flags
|= MSG_DONTWAIT
;
3669 msg
.msg_flags
= flags
;
3670 ret
= sock_sendmsg(sock
, &msg
);
3671 if (force_nonblock
&& ret
== -EAGAIN
)
3673 if (ret
== -ERESTARTSYS
)
3677 io_cqring_add_event(req
, ret
);
3679 req_set_fail_links(req
);
3684 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
, struct io_async_ctx
*io
)
3686 struct io_sr_msg
*sr
= &req
->sr_msg
;
3687 struct iovec __user
*uiov
;
3691 ret
= __copy_msghdr_from_user(&io
->msg
.msg
, sr
->msg
, &io
->msg
.uaddr
,
3696 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3699 if (copy_from_user(io
->msg
.iov
, uiov
, sizeof(*uiov
)))
3701 sr
->len
= io
->msg
.iov
[0].iov_len
;
3702 iov_iter_init(&io
->msg
.msg
.msg_iter
, READ
, io
->msg
.iov
, 1,
3706 ret
= import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
3707 &io
->msg
.iov
, &io
->msg
.msg
.msg_iter
);
3715 #ifdef CONFIG_COMPAT
3716 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
3717 struct io_async_ctx
*io
)
3719 struct compat_msghdr __user
*msg_compat
;
3720 struct io_sr_msg
*sr
= &req
->sr_msg
;
3721 struct compat_iovec __user
*uiov
;
3726 msg_compat
= (struct compat_msghdr __user
*) sr
->msg
;
3727 ret
= __get_compat_msghdr(&io
->msg
.msg
, msg_compat
, &io
->msg
.uaddr
,
3732 uiov
= compat_ptr(ptr
);
3733 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3734 compat_ssize_t clen
;
3738 if (!access_ok(uiov
, sizeof(*uiov
)))
3740 if (__get_user(clen
, &uiov
->iov_len
))
3744 sr
->len
= io
->msg
.iov
[0].iov_len
;
3747 ret
= compat_import_iovec(READ
, uiov
, len
, UIO_FASTIOV
,
3749 &io
->msg
.msg
.msg_iter
);
3758 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
, struct io_async_ctx
*io
)
3760 io
->msg
.iov
= io
->msg
.fast_iov
;
3762 #ifdef CONFIG_COMPAT
3763 if (req
->ctx
->compat
)
3764 return __io_compat_recvmsg_copy_hdr(req
, io
);
3767 return __io_recvmsg_copy_hdr(req
, io
);
3770 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
3771 int *cflags
, bool needs_lock
)
3773 struct io_sr_msg
*sr
= &req
->sr_msg
;
3774 struct io_buffer
*kbuf
;
3776 if (!(req
->flags
& REQ_F_BUFFER_SELECT
))
3779 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
3784 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3786 *cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
3787 *cflags
|= IORING_CQE_F_BUFFER
;
3791 static int io_recvmsg_prep(struct io_kiocb
*req
,
3792 const struct io_uring_sqe
*sqe
)
3794 struct io_sr_msg
*sr
= &req
->sr_msg
;
3795 struct io_async_ctx
*io
= req
->io
;
3798 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
3799 sr
->msg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3800 sr
->len
= READ_ONCE(sqe
->len
);
3801 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
3803 #ifdef CONFIG_COMPAT
3804 if (req
->ctx
->compat
)
3805 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
3808 if (!io
|| req
->opcode
== IORING_OP_RECV
)
3810 /* iovec is already imported */
3811 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3814 ret
= io_recvmsg_copy_hdr(req
, io
);
3816 req
->flags
|= REQ_F_NEED_CLEANUP
;
3820 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
)
3822 struct io_async_msghdr
*kmsg
= NULL
;
3823 struct socket
*sock
;
3824 int ret
, cflags
= 0;
3826 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3829 sock
= sock_from_file(req
->file
, &ret
);
3831 struct io_buffer
*kbuf
;
3832 struct io_async_ctx io
;
3836 kmsg
= &req
->io
->msg
;
3837 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
3838 /* if iov is set, it's allocated already */
3840 kmsg
->iov
= kmsg
->fast_iov
;
3841 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
3844 kmsg
->msg
.msg_name
= &io
.msg
.addr
;
3846 ret
= io_recvmsg_copy_hdr(req
, &io
);
3851 kbuf
= io_recv_buffer_select(req
, &cflags
, !force_nonblock
);
3853 return PTR_ERR(kbuf
);
3855 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3856 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
3857 1, req
->sr_msg
.len
);
3860 flags
= req
->sr_msg
.msg_flags
;
3861 if (flags
& MSG_DONTWAIT
)
3862 req
->flags
|= REQ_F_NOWAIT
;
3863 else if (force_nonblock
)
3864 flags
|= MSG_DONTWAIT
;
3866 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.msg
,
3867 kmsg
->uaddr
, flags
);
3868 if (force_nonblock
&& ret
== -EAGAIN
)
3869 return io_setup_async_msg(req
, kmsg
);
3870 if (ret
== -ERESTARTSYS
)
3874 if (kmsg
&& kmsg
->iov
!= kmsg
->fast_iov
)
3876 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3877 __io_cqring_add_event(req
, ret
, cflags
);
3879 req_set_fail_links(req
);
3884 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
)
3886 struct io_buffer
*kbuf
= NULL
;
3887 struct socket
*sock
;
3888 int ret
, cflags
= 0;
3890 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3893 sock
= sock_from_file(req
->file
, &ret
);
3895 struct io_sr_msg
*sr
= &req
->sr_msg
;
3896 void __user
*buf
= sr
->buf
;
3901 kbuf
= io_recv_buffer_select(req
, &cflags
, !force_nonblock
);
3903 return PTR_ERR(kbuf
);
3905 buf
= u64_to_user_ptr(kbuf
->addr
);
3907 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
,
3914 req
->flags
|= REQ_F_NEED_CLEANUP
;
3915 msg
.msg_name
= NULL
;
3916 msg
.msg_control
= NULL
;
3917 msg
.msg_controllen
= 0;
3918 msg
.msg_namelen
= 0;
3919 msg
.msg_iocb
= NULL
;
3922 flags
= req
->sr_msg
.msg_flags
;
3923 if (flags
& MSG_DONTWAIT
)
3924 req
->flags
|= REQ_F_NOWAIT
;
3925 else if (force_nonblock
)
3926 flags
|= MSG_DONTWAIT
;
3928 ret
= sock_recvmsg(sock
, &msg
, flags
);
3929 if (force_nonblock
&& ret
== -EAGAIN
)
3931 if (ret
== -ERESTARTSYS
)
3936 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3937 __io_cqring_add_event(req
, ret
, cflags
);
3939 req_set_fail_links(req
);
3944 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3946 struct io_accept
*accept
= &req
->accept
;
3948 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3950 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
3953 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3954 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3955 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
3956 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
3960 static int __io_accept(struct io_kiocb
*req
, bool force_nonblock
)
3962 struct io_accept
*accept
= &req
->accept
;
3963 unsigned file_flags
;
3966 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
3967 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
3968 accept
->addr_len
, accept
->flags
,
3970 if (ret
== -EAGAIN
&& force_nonblock
)
3972 if (ret
== -ERESTARTSYS
)
3975 req_set_fail_links(req
);
3976 io_cqring_add_event(req
, ret
);
3981 static void io_accept_finish(struct io_wq_work
**workptr
)
3983 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3985 if (io_req_cancelled(req
))
3987 __io_accept(req
, false);
3988 io_steal_work(req
, workptr
);
3991 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
)
3995 ret
= __io_accept(req
, force_nonblock
);
3996 if (ret
== -EAGAIN
&& force_nonblock
) {
3997 req
->work
.func
= io_accept_finish
;
4003 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4005 struct io_connect
*conn
= &req
->connect
;
4006 struct io_async_ctx
*io
= req
->io
;
4008 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4010 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4013 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4014 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4019 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4020 &io
->connect
.address
);
4023 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
)
4025 struct io_async_ctx __io
, *io
;
4026 unsigned file_flags
;
4032 ret
= move_addr_to_kernel(req
->connect
.addr
,
4033 req
->connect
.addr_len
,
4034 &__io
.connect
.address
);
4040 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4042 ret
= __sys_connect_file(req
->file
, &io
->connect
.address
,
4043 req
->connect
.addr_len
, file_flags
);
4044 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4047 if (io_alloc_async_ctx(req
)) {
4051 memcpy(&req
->io
->connect
, &__io
.connect
, sizeof(__io
.connect
));
4054 if (ret
== -ERESTARTSYS
)
4058 req_set_fail_links(req
);
4059 io_cqring_add_event(req
, ret
);
4063 #else /* !CONFIG_NET */
4064 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4069 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
)
4074 static int io_send(struct io_kiocb
*req
, bool force_nonblock
)
4079 static int io_recvmsg_prep(struct io_kiocb
*req
,
4080 const struct io_uring_sqe
*sqe
)
4085 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
)
4090 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
)
4095 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4100 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
)
4105 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4110 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
)
4114 #endif /* CONFIG_NET */
4116 struct io_poll_table
{
4117 struct poll_table_struct pt
;
4118 struct io_kiocb
*req
;
4122 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
4123 struct wait_queue_head
*head
)
4125 if (unlikely(poll
->head
)) {
4126 pt
->error
= -EINVAL
;
4132 add_wait_queue(head
, &poll
->wait
);
4135 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4136 struct poll_table_struct
*p
)
4138 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4140 __io_queue_proc(&pt
->req
->apoll
->poll
, pt
, head
);
4143 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4144 __poll_t mask
, task_work_func_t func
)
4146 struct task_struct
*tsk
;
4149 /* for instances that support it check for an event match first: */
4150 if (mask
&& !(mask
& poll
->events
))
4153 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4155 list_del_init(&poll
->wait
.entry
);
4159 init_task_work(&req
->task_work
, func
);
4161 * If this fails, then the task is exiting. Punt to one of the io-wq
4162 * threads to ensure the work gets run, we can't always rely on exit
4163 * cancelation taking care of this.
4165 ret
= task_work_add(tsk
, &req
->task_work
, true);
4166 if (unlikely(ret
)) {
4167 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
4168 task_work_add(tsk
, &req
->task_work
, true);
4170 wake_up_process(tsk
);
4174 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4175 __acquires(&req
->ctx
->completion_lock
)
4177 struct io_ring_ctx
*ctx
= req
->ctx
;
4179 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4180 struct poll_table_struct pt
= { ._key
= poll
->events
};
4182 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4185 spin_lock_irq(&ctx
->completion_lock
);
4186 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4187 add_wait_queue(poll
->head
, &poll
->wait
);
4194 static void io_async_task_func(struct callback_head
*cb
)
4196 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4197 struct async_poll
*apoll
= req
->apoll
;
4198 struct io_ring_ctx
*ctx
= req
->ctx
;
4201 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
4203 if (io_poll_rewait(req
, &apoll
->poll
)) {
4204 spin_unlock_irq(&ctx
->completion_lock
);
4208 if (hash_hashed(&req
->hash_node
))
4209 hash_del(&req
->hash_node
);
4211 canceled
= READ_ONCE(apoll
->poll
.canceled
);
4213 io_cqring_fill_event(req
, -ECANCELED
);
4214 io_commit_cqring(ctx
);
4217 spin_unlock_irq(&ctx
->completion_lock
);
4219 /* restore ->work in case we need to retry again */
4220 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4224 io_cqring_ev_posted(ctx
);
4225 req_set_fail_links(req
);
4226 io_double_put_req(req
);
4230 __set_current_state(TASK_RUNNING
);
4231 mutex_lock(&ctx
->uring_lock
);
4232 __io_queue_sqe(req
, NULL
);
4233 mutex_unlock(&ctx
->uring_lock
);
4238 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4241 struct io_kiocb
*req
= wait
->private;
4242 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
4244 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
4247 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
4250 static void io_poll_req_insert(struct io_kiocb
*req
)
4252 struct io_ring_ctx
*ctx
= req
->ctx
;
4253 struct hlist_head
*list
;
4255 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
4256 hlist_add_head(&req
->hash_node
, list
);
4259 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
4260 struct io_poll_iocb
*poll
,
4261 struct io_poll_table
*ipt
, __poll_t mask
,
4262 wait_queue_func_t wake_func
)
4263 __acquires(&ctx
->completion_lock
)
4265 struct io_ring_ctx
*ctx
= req
->ctx
;
4266 bool cancel
= false;
4268 poll
->file
= req
->file
;
4270 poll
->done
= poll
->canceled
= false;
4271 poll
->events
= mask
;
4273 ipt
->pt
._key
= mask
;
4275 ipt
->error
= -EINVAL
;
4277 INIT_LIST_HEAD(&poll
->wait
.entry
);
4278 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
4279 poll
->wait
.private = req
;
4281 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
4283 spin_lock_irq(&ctx
->completion_lock
);
4284 if (likely(poll
->head
)) {
4285 spin_lock(&poll
->head
->lock
);
4286 if (unlikely(list_empty(&poll
->wait
.entry
))) {
4292 if (mask
|| ipt
->error
)
4293 list_del_init(&poll
->wait
.entry
);
4295 WRITE_ONCE(poll
->canceled
, true);
4296 else if (!poll
->done
) /* actually waiting for an event */
4297 io_poll_req_insert(req
);
4298 spin_unlock(&poll
->head
->lock
);
4304 static bool io_arm_poll_handler(struct io_kiocb
*req
)
4306 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
4307 struct io_ring_ctx
*ctx
= req
->ctx
;
4308 struct async_poll
*apoll
;
4309 struct io_poll_table ipt
;
4312 if (!req
->file
|| !file_can_poll(req
->file
))
4314 if (req
->flags
& (REQ_F_MUST_PUNT
| REQ_F_POLLED
))
4316 if (!def
->pollin
&& !def
->pollout
)
4319 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
4320 if (unlikely(!apoll
))
4323 req
->flags
|= REQ_F_POLLED
;
4324 memcpy(&apoll
->work
, &req
->work
, sizeof(req
->work
));
4326 get_task_struct(current
);
4327 req
->task
= current
;
4329 INIT_HLIST_NODE(&req
->hash_node
);
4333 mask
|= POLLIN
| POLLRDNORM
;
4335 mask
|= POLLOUT
| POLLWRNORM
;
4336 mask
|= POLLERR
| POLLPRI
;
4338 ipt
.pt
._qproc
= io_async_queue_proc
;
4340 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
4344 apoll
->poll
.done
= true;
4345 spin_unlock_irq(&ctx
->completion_lock
);
4346 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4350 spin_unlock_irq(&ctx
->completion_lock
);
4351 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
4352 apoll
->poll
.events
);
4356 static bool __io_poll_remove_one(struct io_kiocb
*req
,
4357 struct io_poll_iocb
*poll
)
4359 bool do_complete
= false;
4361 spin_lock(&poll
->head
->lock
);
4362 WRITE_ONCE(poll
->canceled
, true);
4363 if (!list_empty(&poll
->wait
.entry
)) {
4364 list_del_init(&poll
->wait
.entry
);
4367 spin_unlock(&poll
->head
->lock
);
4371 static bool io_poll_remove_one(struct io_kiocb
*req
)
4373 struct async_poll
*apoll
= NULL
;
4376 if (req
->opcode
== IORING_OP_POLL_ADD
) {
4377 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
4380 /* non-poll requests have submit ref still */
4381 do_complete
= __io_poll_remove_one(req
, &req
->apoll
->poll
);
4386 hash_del(&req
->hash_node
);
4388 if (do_complete
&& apoll
) {
4390 * restore ->work because we need to call io_req_work_drop_env.
4392 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4397 io_cqring_fill_event(req
, -ECANCELED
);
4398 io_commit_cqring(req
->ctx
);
4399 req
->flags
|= REQ_F_COMP_LOCKED
;
4406 static void io_poll_remove_all(struct io_ring_ctx
*ctx
)
4408 struct hlist_node
*tmp
;
4409 struct io_kiocb
*req
;
4412 spin_lock_irq(&ctx
->completion_lock
);
4413 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
4414 struct hlist_head
*list
;
4416 list
= &ctx
->cancel_hash
[i
];
4417 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
)
4418 posted
+= io_poll_remove_one(req
);
4420 spin_unlock_irq(&ctx
->completion_lock
);
4423 io_cqring_ev_posted(ctx
);
4426 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
4428 struct hlist_head
*list
;
4429 struct io_kiocb
*req
;
4431 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
4432 hlist_for_each_entry(req
, list
, hash_node
) {
4433 if (sqe_addr
!= req
->user_data
)
4435 if (io_poll_remove_one(req
))
4443 static int io_poll_remove_prep(struct io_kiocb
*req
,
4444 const struct io_uring_sqe
*sqe
)
4446 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4448 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
4452 req
->poll
.addr
= READ_ONCE(sqe
->addr
);
4457 * Find a running poll command that matches one specified in sqe->addr,
4458 * and remove it if found.
4460 static int io_poll_remove(struct io_kiocb
*req
)
4462 struct io_ring_ctx
*ctx
= req
->ctx
;
4466 addr
= req
->poll
.addr
;
4467 spin_lock_irq(&ctx
->completion_lock
);
4468 ret
= io_poll_cancel(ctx
, addr
);
4469 spin_unlock_irq(&ctx
->completion_lock
);
4471 io_cqring_add_event(req
, ret
);
4473 req_set_fail_links(req
);
4478 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4480 struct io_ring_ctx
*ctx
= req
->ctx
;
4482 req
->poll
.done
= true;
4483 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
4484 io_commit_cqring(ctx
);
4487 static void io_poll_task_handler(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
4489 struct io_ring_ctx
*ctx
= req
->ctx
;
4490 struct io_poll_iocb
*poll
= &req
->poll
;
4492 if (io_poll_rewait(req
, poll
)) {
4493 spin_unlock_irq(&ctx
->completion_lock
);
4497 hash_del(&req
->hash_node
);
4498 io_poll_complete(req
, req
->result
, 0);
4499 req
->flags
|= REQ_F_COMP_LOCKED
;
4500 io_put_req_find_next(req
, nxt
);
4501 spin_unlock_irq(&ctx
->completion_lock
);
4503 io_cqring_ev_posted(ctx
);
4506 static void io_poll_task_func(struct callback_head
*cb
)
4508 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4509 struct io_kiocb
*nxt
= NULL
;
4511 io_poll_task_handler(req
, &nxt
);
4513 struct io_ring_ctx
*ctx
= nxt
->ctx
;
4515 mutex_lock(&ctx
->uring_lock
);
4516 __io_queue_sqe(nxt
, NULL
);
4517 mutex_unlock(&ctx
->uring_lock
);
4521 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4524 struct io_kiocb
*req
= wait
->private;
4525 struct io_poll_iocb
*poll
= &req
->poll
;
4527 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
4530 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4531 struct poll_table_struct
*p
)
4533 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4535 __io_queue_proc(&pt
->req
->poll
, pt
, head
);
4538 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4540 struct io_poll_iocb
*poll
= &req
->poll
;
4543 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4545 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
4550 events
= READ_ONCE(sqe
->poll_events
);
4551 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
;
4553 get_task_struct(current
);
4554 req
->task
= current
;
4558 static int io_poll_add(struct io_kiocb
*req
)
4560 struct io_poll_iocb
*poll
= &req
->poll
;
4561 struct io_ring_ctx
*ctx
= req
->ctx
;
4562 struct io_poll_table ipt
;
4565 INIT_HLIST_NODE(&req
->hash_node
);
4566 INIT_LIST_HEAD(&req
->list
);
4567 ipt
.pt
._qproc
= io_poll_queue_proc
;
4569 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
4572 if (mask
) { /* no async, we'd stolen it */
4574 io_poll_complete(req
, mask
, 0);
4576 spin_unlock_irq(&ctx
->completion_lock
);
4579 io_cqring_ev_posted(ctx
);
4585 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
4587 struct io_timeout_data
*data
= container_of(timer
,
4588 struct io_timeout_data
, timer
);
4589 struct io_kiocb
*req
= data
->req
;
4590 struct io_ring_ctx
*ctx
= req
->ctx
;
4591 unsigned long flags
;
4593 atomic_inc(&ctx
->cq_timeouts
);
4595 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4597 * We could be racing with timeout deletion. If the list is empty,
4598 * then timeout lookup already found it and will be handling it.
4600 if (!list_empty(&req
->list
)) {
4601 struct io_kiocb
*prev
;
4604 * Adjust the reqs sequence before the current one because it
4605 * will consume a slot in the cq_ring and the cq_tail
4606 * pointer will be increased, otherwise other timeout reqs may
4607 * return in advance without waiting for enough wait_nr.
4610 list_for_each_entry_continue_reverse(prev
, &ctx
->timeout_list
, list
)
4612 list_del_init(&req
->list
);
4615 io_cqring_fill_event(req
, -ETIME
);
4616 io_commit_cqring(ctx
);
4617 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
4619 io_cqring_ev_posted(ctx
);
4620 req_set_fail_links(req
);
4622 return HRTIMER_NORESTART
;
4625 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
4627 struct io_kiocb
*req
;
4630 list_for_each_entry(req
, &ctx
->timeout_list
, list
) {
4631 if (user_data
== req
->user_data
) {
4632 list_del_init(&req
->list
);
4641 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
4645 req_set_fail_links(req
);
4646 io_cqring_fill_event(req
, -ECANCELED
);
4651 static int io_timeout_remove_prep(struct io_kiocb
*req
,
4652 const struct io_uring_sqe
*sqe
)
4654 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4656 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
4659 req
->timeout
.addr
= READ_ONCE(sqe
->addr
);
4660 req
->timeout
.flags
= READ_ONCE(sqe
->timeout_flags
);
4661 if (req
->timeout
.flags
)
4668 * Remove or update an existing timeout command
4670 static int io_timeout_remove(struct io_kiocb
*req
)
4672 struct io_ring_ctx
*ctx
= req
->ctx
;
4675 spin_lock_irq(&ctx
->completion_lock
);
4676 ret
= io_timeout_cancel(ctx
, req
->timeout
.addr
);
4678 io_cqring_fill_event(req
, ret
);
4679 io_commit_cqring(ctx
);
4680 spin_unlock_irq(&ctx
->completion_lock
);
4681 io_cqring_ev_posted(ctx
);
4683 req_set_fail_links(req
);
4688 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
4689 bool is_timeout_link
)
4691 struct io_timeout_data
*data
;
4694 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4696 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
4698 if (sqe
->off
&& is_timeout_link
)
4700 flags
= READ_ONCE(sqe
->timeout_flags
);
4701 if (flags
& ~IORING_TIMEOUT_ABS
)
4704 req
->timeout
.count
= READ_ONCE(sqe
->off
);
4706 if (!req
->io
&& io_alloc_async_ctx(req
))
4709 data
= &req
->io
->timeout
;
4711 req
->flags
|= REQ_F_TIMEOUT
;
4713 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
4716 if (flags
& IORING_TIMEOUT_ABS
)
4717 data
->mode
= HRTIMER_MODE_ABS
;
4719 data
->mode
= HRTIMER_MODE_REL
;
4721 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
4725 static int io_timeout(struct io_kiocb
*req
)
4727 struct io_ring_ctx
*ctx
= req
->ctx
;
4728 struct io_timeout_data
*data
;
4729 struct list_head
*entry
;
4731 u32 count
= req
->timeout
.count
;
4732 u32 seq
= req
->sequence
;
4734 data
= &req
->io
->timeout
;
4737 * sqe->off holds how many events that need to occur for this
4738 * timeout event to be satisfied. If it isn't set, then this is
4739 * a pure timeout request, sequence isn't used.
4742 req
->flags
|= REQ_F_TIMEOUT_NOSEQ
;
4743 spin_lock_irq(&ctx
->completion_lock
);
4744 entry
= ctx
->timeout_list
.prev
;
4748 req
->sequence
= seq
+ count
;
4751 * Insertion sort, ensuring the first entry in the list is always
4752 * the one we need first.
4754 spin_lock_irq(&ctx
->completion_lock
);
4755 list_for_each_prev(entry
, &ctx
->timeout_list
) {
4756 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
, list
);
4758 long long tmp
, tmp_nxt
;
4759 u32 nxt_offset
= nxt
->timeout
.count
;
4761 if (nxt
->flags
& REQ_F_TIMEOUT_NOSEQ
)
4765 * Since seq + count can overflow, use type long
4768 tmp
= (long long)seq
+ count
;
4769 nxt_seq
= nxt
->sequence
- nxt_offset
;
4770 tmp_nxt
= (long long)nxt_seq
+ nxt_offset
;
4773 * cached_sq_head may overflow, and it will never overflow twice
4774 * once there is some timeout req still be valid.
4783 * Sequence of reqs after the insert one and itself should
4784 * be adjusted because each timeout req consumes a slot.
4789 req
->sequence
-= span
;
4791 list_add(&req
->list
, entry
);
4792 data
->timer
.function
= io_timeout_fn
;
4793 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
4794 spin_unlock_irq(&ctx
->completion_lock
);
4798 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
4800 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
4802 return req
->user_data
== (unsigned long) data
;
4805 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
4807 enum io_wq_cancel cancel_ret
;
4810 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
);
4811 switch (cancel_ret
) {
4812 case IO_WQ_CANCEL_OK
:
4815 case IO_WQ_CANCEL_RUNNING
:
4818 case IO_WQ_CANCEL_NOTFOUND
:
4826 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
4827 struct io_kiocb
*req
, __u64 sqe_addr
,
4830 unsigned long flags
;
4833 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
4834 if (ret
!= -ENOENT
) {
4835 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4839 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4840 ret
= io_timeout_cancel(ctx
, sqe_addr
);
4843 ret
= io_poll_cancel(ctx
, sqe_addr
);
4847 io_cqring_fill_event(req
, ret
);
4848 io_commit_cqring(ctx
);
4849 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
4850 io_cqring_ev_posted(ctx
);
4853 req_set_fail_links(req
);
4857 static int io_async_cancel_prep(struct io_kiocb
*req
,
4858 const struct io_uring_sqe
*sqe
)
4860 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4862 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
||
4866 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
4870 static int io_async_cancel(struct io_kiocb
*req
)
4872 struct io_ring_ctx
*ctx
= req
->ctx
;
4874 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
4878 static int io_files_update_prep(struct io_kiocb
*req
,
4879 const struct io_uring_sqe
*sqe
)
4881 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->rw_flags
)
4884 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
4885 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
4886 if (!req
->files_update
.nr_args
)
4888 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
4892 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
)
4894 struct io_ring_ctx
*ctx
= req
->ctx
;
4895 struct io_uring_files_update up
;
4901 up
.offset
= req
->files_update
.offset
;
4902 up
.fds
= req
->files_update
.arg
;
4904 mutex_lock(&ctx
->uring_lock
);
4905 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
4906 mutex_unlock(&ctx
->uring_lock
);
4909 req_set_fail_links(req
);
4910 io_cqring_add_event(req
, ret
);
4915 static int io_req_defer_prep(struct io_kiocb
*req
,
4916 const struct io_uring_sqe
*sqe
)
4923 if (io_op_defs
[req
->opcode
].file_table
) {
4924 ret
= io_grab_files(req
);
4929 io_req_work_grab_env(req
, &io_op_defs
[req
->opcode
]);
4931 switch (req
->opcode
) {
4934 case IORING_OP_READV
:
4935 case IORING_OP_READ_FIXED
:
4936 case IORING_OP_READ
:
4937 ret
= io_read_prep(req
, sqe
, true);
4939 case IORING_OP_WRITEV
:
4940 case IORING_OP_WRITE_FIXED
:
4941 case IORING_OP_WRITE
:
4942 ret
= io_write_prep(req
, sqe
, true);
4944 case IORING_OP_POLL_ADD
:
4945 ret
= io_poll_add_prep(req
, sqe
);
4947 case IORING_OP_POLL_REMOVE
:
4948 ret
= io_poll_remove_prep(req
, sqe
);
4950 case IORING_OP_FSYNC
:
4951 ret
= io_prep_fsync(req
, sqe
);
4953 case IORING_OP_SYNC_FILE_RANGE
:
4954 ret
= io_prep_sfr(req
, sqe
);
4956 case IORING_OP_SENDMSG
:
4957 case IORING_OP_SEND
:
4958 ret
= io_sendmsg_prep(req
, sqe
);
4960 case IORING_OP_RECVMSG
:
4961 case IORING_OP_RECV
:
4962 ret
= io_recvmsg_prep(req
, sqe
);
4964 case IORING_OP_CONNECT
:
4965 ret
= io_connect_prep(req
, sqe
);
4967 case IORING_OP_TIMEOUT
:
4968 ret
= io_timeout_prep(req
, sqe
, false);
4970 case IORING_OP_TIMEOUT_REMOVE
:
4971 ret
= io_timeout_remove_prep(req
, sqe
);
4973 case IORING_OP_ASYNC_CANCEL
:
4974 ret
= io_async_cancel_prep(req
, sqe
);
4976 case IORING_OP_LINK_TIMEOUT
:
4977 ret
= io_timeout_prep(req
, sqe
, true);
4979 case IORING_OP_ACCEPT
:
4980 ret
= io_accept_prep(req
, sqe
);
4982 case IORING_OP_FALLOCATE
:
4983 ret
= io_fallocate_prep(req
, sqe
);
4985 case IORING_OP_OPENAT
:
4986 ret
= io_openat_prep(req
, sqe
);
4988 case IORING_OP_CLOSE
:
4989 ret
= io_close_prep(req
, sqe
);
4991 case IORING_OP_FILES_UPDATE
:
4992 ret
= io_files_update_prep(req
, sqe
);
4994 case IORING_OP_STATX
:
4995 ret
= io_statx_prep(req
, sqe
);
4997 case IORING_OP_FADVISE
:
4998 ret
= io_fadvise_prep(req
, sqe
);
5000 case IORING_OP_MADVISE
:
5001 ret
= io_madvise_prep(req
, sqe
);
5003 case IORING_OP_OPENAT2
:
5004 ret
= io_openat2_prep(req
, sqe
);
5006 case IORING_OP_EPOLL_CTL
:
5007 ret
= io_epoll_ctl_prep(req
, sqe
);
5009 case IORING_OP_SPLICE
:
5010 ret
= io_splice_prep(req
, sqe
);
5012 case IORING_OP_PROVIDE_BUFFERS
:
5013 ret
= io_provide_buffers_prep(req
, sqe
);
5015 case IORING_OP_REMOVE_BUFFERS
:
5016 ret
= io_remove_buffers_prep(req
, sqe
);
5019 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5028 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5030 struct io_ring_ctx
*ctx
= req
->ctx
;
5033 /* Still need defer if there is pending req in defer list. */
5034 if (!req_need_defer(req
) && list_empty(&ctx
->defer_list
))
5037 if (!req
->io
&& io_alloc_async_ctx(req
))
5040 ret
= io_req_defer_prep(req
, sqe
);
5044 spin_lock_irq(&ctx
->completion_lock
);
5045 if (!req_need_defer(req
) && list_empty(&ctx
->defer_list
)) {
5046 spin_unlock_irq(&ctx
->completion_lock
);
5050 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5051 list_add_tail(&req
->list
, &ctx
->defer_list
);
5052 spin_unlock_irq(&ctx
->completion_lock
);
5053 return -EIOCBQUEUED
;
5056 static void io_cleanup_req(struct io_kiocb
*req
)
5058 struct io_async_ctx
*io
= req
->io
;
5060 switch (req
->opcode
) {
5061 case IORING_OP_READV
:
5062 case IORING_OP_READ_FIXED
:
5063 case IORING_OP_READ
:
5064 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5065 kfree((void *)(unsigned long)req
->rw
.addr
);
5067 case IORING_OP_WRITEV
:
5068 case IORING_OP_WRITE_FIXED
:
5069 case IORING_OP_WRITE
:
5070 if (io
->rw
.iov
!= io
->rw
.fast_iov
)
5073 case IORING_OP_RECVMSG
:
5074 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5075 kfree(req
->sr_msg
.kbuf
);
5077 case IORING_OP_SENDMSG
:
5078 if (io
->msg
.iov
!= io
->msg
.fast_iov
)
5081 case IORING_OP_RECV
:
5082 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5083 kfree(req
->sr_msg
.kbuf
);
5085 case IORING_OP_OPENAT
:
5086 case IORING_OP_OPENAT2
:
5087 case IORING_OP_STATX
:
5088 putname(req
->open
.filename
);
5090 case IORING_OP_SPLICE
:
5091 io_put_file(req
, req
->splice
.file_in
,
5092 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
5096 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5099 static int io_issue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5100 bool force_nonblock
)
5102 struct io_ring_ctx
*ctx
= req
->ctx
;
5105 switch (req
->opcode
) {
5109 case IORING_OP_READV
:
5110 case IORING_OP_READ_FIXED
:
5111 case IORING_OP_READ
:
5113 ret
= io_read_prep(req
, sqe
, force_nonblock
);
5117 ret
= io_read(req
, force_nonblock
);
5119 case IORING_OP_WRITEV
:
5120 case IORING_OP_WRITE_FIXED
:
5121 case IORING_OP_WRITE
:
5123 ret
= io_write_prep(req
, sqe
, force_nonblock
);
5127 ret
= io_write(req
, force_nonblock
);
5129 case IORING_OP_FSYNC
:
5131 ret
= io_prep_fsync(req
, sqe
);
5135 ret
= io_fsync(req
, force_nonblock
);
5137 case IORING_OP_POLL_ADD
:
5139 ret
= io_poll_add_prep(req
, sqe
);
5143 ret
= io_poll_add(req
);
5145 case IORING_OP_POLL_REMOVE
:
5147 ret
= io_poll_remove_prep(req
, sqe
);
5151 ret
= io_poll_remove(req
);
5153 case IORING_OP_SYNC_FILE_RANGE
:
5155 ret
= io_prep_sfr(req
, sqe
);
5159 ret
= io_sync_file_range(req
, force_nonblock
);
5161 case IORING_OP_SENDMSG
:
5162 case IORING_OP_SEND
:
5164 ret
= io_sendmsg_prep(req
, sqe
);
5168 if (req
->opcode
== IORING_OP_SENDMSG
)
5169 ret
= io_sendmsg(req
, force_nonblock
);
5171 ret
= io_send(req
, force_nonblock
);
5173 case IORING_OP_RECVMSG
:
5174 case IORING_OP_RECV
:
5176 ret
= io_recvmsg_prep(req
, sqe
);
5180 if (req
->opcode
== IORING_OP_RECVMSG
)
5181 ret
= io_recvmsg(req
, force_nonblock
);
5183 ret
= io_recv(req
, force_nonblock
);
5185 case IORING_OP_TIMEOUT
:
5187 ret
= io_timeout_prep(req
, sqe
, false);
5191 ret
= io_timeout(req
);
5193 case IORING_OP_TIMEOUT_REMOVE
:
5195 ret
= io_timeout_remove_prep(req
, sqe
);
5199 ret
= io_timeout_remove(req
);
5201 case IORING_OP_ACCEPT
:
5203 ret
= io_accept_prep(req
, sqe
);
5207 ret
= io_accept(req
, force_nonblock
);
5209 case IORING_OP_CONNECT
:
5211 ret
= io_connect_prep(req
, sqe
);
5215 ret
= io_connect(req
, force_nonblock
);
5217 case IORING_OP_ASYNC_CANCEL
:
5219 ret
= io_async_cancel_prep(req
, sqe
);
5223 ret
= io_async_cancel(req
);
5225 case IORING_OP_FALLOCATE
:
5227 ret
= io_fallocate_prep(req
, sqe
);
5231 ret
= io_fallocate(req
, force_nonblock
);
5233 case IORING_OP_OPENAT
:
5235 ret
= io_openat_prep(req
, sqe
);
5239 ret
= io_openat(req
, force_nonblock
);
5241 case IORING_OP_CLOSE
:
5243 ret
= io_close_prep(req
, sqe
);
5247 ret
= io_close(req
, force_nonblock
);
5249 case IORING_OP_FILES_UPDATE
:
5251 ret
= io_files_update_prep(req
, sqe
);
5255 ret
= io_files_update(req
, force_nonblock
);
5257 case IORING_OP_STATX
:
5259 ret
= io_statx_prep(req
, sqe
);
5263 ret
= io_statx(req
, force_nonblock
);
5265 case IORING_OP_FADVISE
:
5267 ret
= io_fadvise_prep(req
, sqe
);
5271 ret
= io_fadvise(req
, force_nonblock
);
5273 case IORING_OP_MADVISE
:
5275 ret
= io_madvise_prep(req
, sqe
);
5279 ret
= io_madvise(req
, force_nonblock
);
5281 case IORING_OP_OPENAT2
:
5283 ret
= io_openat2_prep(req
, sqe
);
5287 ret
= io_openat2(req
, force_nonblock
);
5289 case IORING_OP_EPOLL_CTL
:
5291 ret
= io_epoll_ctl_prep(req
, sqe
);
5295 ret
= io_epoll_ctl(req
, force_nonblock
);
5297 case IORING_OP_SPLICE
:
5299 ret
= io_splice_prep(req
, sqe
);
5303 ret
= io_splice(req
, force_nonblock
);
5305 case IORING_OP_PROVIDE_BUFFERS
:
5307 ret
= io_provide_buffers_prep(req
, sqe
);
5311 ret
= io_provide_buffers(req
, force_nonblock
);
5313 case IORING_OP_REMOVE_BUFFERS
:
5315 ret
= io_remove_buffers_prep(req
, sqe
);
5319 ret
= io_remove_buffers(req
, force_nonblock
);
5329 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
5330 const bool in_async
= io_wq_current_is_worker();
5332 if (req
->result
== -EAGAIN
)
5335 /* workqueue context doesn't hold uring_lock, grab it now */
5337 mutex_lock(&ctx
->uring_lock
);
5339 io_iopoll_req_issued(req
);
5342 mutex_unlock(&ctx
->uring_lock
);
5348 static void io_wq_submit_work(struct io_wq_work
**workptr
)
5350 struct io_wq_work
*work
= *workptr
;
5351 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5354 /* if NO_CANCEL is set, we must still run the work */
5355 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
5356 IO_WQ_WORK_CANCEL
) {
5362 ret
= io_issue_sqe(req
, NULL
, false);
5364 * We can get EAGAIN for polled IO even though we're
5365 * forcing a sync submission from here, since we can't
5366 * wait for request slots on the block side.
5375 req_set_fail_links(req
);
5376 io_cqring_add_event(req
, ret
);
5380 io_steal_work(req
, workptr
);
5383 static int io_req_needs_file(struct io_kiocb
*req
, int fd
)
5385 if (!io_op_defs
[req
->opcode
].needs_file
)
5387 if ((fd
== -1 || fd
== AT_FDCWD
) && io_op_defs
[req
->opcode
].fd_non_neg
)
5392 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
5395 struct fixed_file_table
*table
;
5397 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
5398 return table
->files
[index
& IORING_FILE_TABLE_MASK
];;
5401 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
5402 int fd
, struct file
**out_file
, bool fixed
)
5404 struct io_ring_ctx
*ctx
= req
->ctx
;
5408 if (unlikely(!ctx
->file_data
||
5409 (unsigned) fd
>= ctx
->nr_user_files
))
5411 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
5412 file
= io_file_from_index(ctx
, fd
);
5415 req
->fixed_file_refs
= ctx
->file_data
->cur_refs
;
5416 percpu_ref_get(req
->fixed_file_refs
);
5418 trace_io_uring_file_get(ctx
, fd
);
5419 file
= __io_file_get(state
, fd
);
5420 if (unlikely(!file
))
5428 static int io_req_set_file(struct io_submit_state
*state
, struct io_kiocb
*req
,
5429 int fd
, unsigned int flags
)
5433 if (!io_req_needs_file(req
, fd
))
5436 fixed
= (flags
& IOSQE_FIXED_FILE
);
5437 if (unlikely(!fixed
&& req
->needs_fixed_file
))
5440 return io_file_get(state
, req
, fd
, &req
->file
, fixed
);
5443 static int io_grab_files(struct io_kiocb
*req
)
5446 struct io_ring_ctx
*ctx
= req
->ctx
;
5448 if (req
->work
.files
|| (req
->flags
& REQ_F_NO_FILE_TABLE
))
5450 if (!ctx
->ring_file
)
5454 spin_lock_irq(&ctx
->inflight_lock
);
5456 * We use the f_ops->flush() handler to ensure that we can flush
5457 * out work accessing these files if the fd is closed. Check if
5458 * the fd has changed since we started down this path, and disallow
5459 * this operation if it has.
5461 if (fcheck(ctx
->ring_fd
) == ctx
->ring_file
) {
5462 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
5463 req
->flags
|= REQ_F_INFLIGHT
;
5464 req
->work
.files
= current
->files
;
5467 spin_unlock_irq(&ctx
->inflight_lock
);
5473 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
5475 struct io_timeout_data
*data
= container_of(timer
,
5476 struct io_timeout_data
, timer
);
5477 struct io_kiocb
*req
= data
->req
;
5478 struct io_ring_ctx
*ctx
= req
->ctx
;
5479 struct io_kiocb
*prev
= NULL
;
5480 unsigned long flags
;
5482 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5485 * We don't expect the list to be empty, that will only happen if we
5486 * race with the completion of the linked work.
5488 if (!list_empty(&req
->link_list
)) {
5489 prev
= list_entry(req
->link_list
.prev
, struct io_kiocb
,
5491 if (refcount_inc_not_zero(&prev
->refs
)) {
5492 list_del_init(&req
->link_list
);
5493 prev
->flags
&= ~REQ_F_LINK_TIMEOUT
;
5498 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5501 req_set_fail_links(prev
);
5502 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
5505 io_cqring_add_event(req
, -ETIME
);
5508 return HRTIMER_NORESTART
;
5511 static void io_queue_linked_timeout(struct io_kiocb
*req
)
5513 struct io_ring_ctx
*ctx
= req
->ctx
;
5516 * If the list is now empty, then our linked request finished before
5517 * we got a chance to setup the timer
5519 spin_lock_irq(&ctx
->completion_lock
);
5520 if (!list_empty(&req
->link_list
)) {
5521 struct io_timeout_data
*data
= &req
->io
->timeout
;
5523 data
->timer
.function
= io_link_timeout_fn
;
5524 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
5527 spin_unlock_irq(&ctx
->completion_lock
);
5529 /* drop submission reference */
5533 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
5535 struct io_kiocb
*nxt
;
5537 if (!(req
->flags
& REQ_F_LINK_HEAD
))
5539 /* for polled retry, if flag is set, we already went through here */
5540 if (req
->flags
& REQ_F_POLLED
)
5543 nxt
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
5545 if (!nxt
|| nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
5548 req
->flags
|= REQ_F_LINK_TIMEOUT
;
5552 static void __io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5554 struct io_kiocb
*linked_timeout
;
5555 struct io_kiocb
*nxt
;
5556 const struct cred
*old_creds
= NULL
;
5560 linked_timeout
= io_prep_linked_timeout(req
);
5562 if (req
->work
.creds
&& req
->work
.creds
!= current_cred()) {
5564 revert_creds(old_creds
);
5565 if (old_creds
== req
->work
.creds
)
5566 old_creds
= NULL
; /* restored original creds */
5568 old_creds
= override_creds(req
->work
.creds
);
5571 ret
= io_issue_sqe(req
, sqe
, true);
5574 * We async punt it if the file wasn't marked NOWAIT, or if the file
5575 * doesn't support non-blocking read/write attempts
5577 if (ret
== -EAGAIN
&& (!(req
->flags
& REQ_F_NOWAIT
) ||
5578 (req
->flags
& REQ_F_MUST_PUNT
))) {
5579 if (io_arm_poll_handler(req
)) {
5581 io_queue_linked_timeout(linked_timeout
);
5585 if (io_op_defs
[req
->opcode
].file_table
) {
5586 ret
= io_grab_files(req
);
5592 * Queued up for async execution, worker will release
5593 * submit reference when the iocb is actually submitted.
5595 io_queue_async_work(req
);
5601 /* drop submission reference */
5602 io_put_req_find_next(req
, &nxt
);
5604 if (linked_timeout
) {
5606 io_queue_linked_timeout(linked_timeout
);
5608 io_put_req(linked_timeout
);
5611 /* and drop final reference, if we failed */
5613 io_cqring_add_event(req
, ret
);
5614 req_set_fail_links(req
);
5620 if (req
->flags
& REQ_F_FORCE_ASYNC
)
5626 revert_creds(old_creds
);
5629 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5633 ret
= io_req_defer(req
, sqe
);
5635 if (ret
!= -EIOCBQUEUED
) {
5637 io_cqring_add_event(req
, ret
);
5638 req_set_fail_links(req
);
5639 io_double_put_req(req
);
5641 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
5642 ret
= io_req_defer_prep(req
, sqe
);
5643 if (unlikely(ret
< 0))
5646 * Never try inline submit of IOSQE_ASYNC is set, go straight
5647 * to async execution.
5649 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
5650 io_queue_async_work(req
);
5652 __io_queue_sqe(req
, sqe
);
5656 static inline void io_queue_link_head(struct io_kiocb
*req
)
5658 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
5659 io_cqring_add_event(req
, -ECANCELED
);
5660 io_double_put_req(req
);
5662 io_queue_sqe(req
, NULL
);
5665 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5666 struct io_submit_state
*state
, struct io_kiocb
**link
)
5668 struct io_ring_ctx
*ctx
= req
->ctx
;
5672 * If we already have a head request, queue this one for async
5673 * submittal once the head completes. If we don't have a head but
5674 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
5675 * submitted sync once the chain is complete. If none of those
5676 * conditions are true (normal request), then just queue it.
5679 struct io_kiocb
*head
= *link
;
5682 * Taking sequential execution of a link, draining both sides
5683 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
5684 * requests in the link. So, it drains the head and the
5685 * next after the link request. The last one is done via
5686 * drain_next flag to persist the effect across calls.
5688 if (req
->flags
& REQ_F_IO_DRAIN
) {
5689 head
->flags
|= REQ_F_IO_DRAIN
;
5690 ctx
->drain_next
= 1;
5692 if (io_alloc_async_ctx(req
))
5695 ret
= io_req_defer_prep(req
, sqe
);
5697 /* fail even hard links since we don't submit */
5698 head
->flags
|= REQ_F_FAIL_LINK
;
5701 trace_io_uring_link(ctx
, req
, head
);
5702 list_add_tail(&req
->link_list
, &head
->link_list
);
5704 /* last request of a link, enqueue the link */
5705 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
5706 io_queue_link_head(head
);
5710 if (unlikely(ctx
->drain_next
)) {
5711 req
->flags
|= REQ_F_IO_DRAIN
;
5712 ctx
->drain_next
= 0;
5714 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
5715 req
->flags
|= REQ_F_LINK_HEAD
;
5716 INIT_LIST_HEAD(&req
->link_list
);
5718 if (io_alloc_async_ctx(req
))
5721 ret
= io_req_defer_prep(req
, sqe
);
5723 req
->flags
|= REQ_F_FAIL_LINK
;
5726 io_queue_sqe(req
, sqe
);
5734 * Batched submission is done, ensure local IO is flushed out.
5736 static void io_submit_state_end(struct io_submit_state
*state
)
5738 blk_finish_plug(&state
->plug
);
5740 if (state
->free_reqs
)
5741 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
5745 * Start submission side cache.
5747 static void io_submit_state_start(struct io_submit_state
*state
,
5748 unsigned int max_ios
)
5750 blk_start_plug(&state
->plug
);
5751 state
->free_reqs
= 0;
5753 state
->ios_left
= max_ios
;
5756 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
5758 struct io_rings
*rings
= ctx
->rings
;
5761 * Ensure any loads from the SQEs are done at this point,
5762 * since once we write the new head, the application could
5763 * write new data to them.
5765 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
5769 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
5770 * that is mapped by userspace. This means that care needs to be taken to
5771 * ensure that reads are stable, as we cannot rely on userspace always
5772 * being a good citizen. If members of the sqe are validated and then later
5773 * used, it's important that those reads are done through READ_ONCE() to
5774 * prevent a re-load down the line.
5776 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
5778 u32
*sq_array
= ctx
->sq_array
;
5782 * The cached sq head (or cq tail) serves two purposes:
5784 * 1) allows us to batch the cost of updating the user visible
5786 * 2) allows the kernel side to track the head on its own, even
5787 * though the application is the one updating it.
5789 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
5790 if (likely(head
< ctx
->sq_entries
))
5791 return &ctx
->sq_sqes
[head
];
5793 /* drop invalid entries */
5794 ctx
->cached_sq_dropped
++;
5795 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
5799 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
5801 ctx
->cached_sq_head
++;
5804 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
5805 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
5806 IOSQE_BUFFER_SELECT)
5808 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
5809 const struct io_uring_sqe
*sqe
,
5810 struct io_submit_state
*state
, bool async
)
5812 unsigned int sqe_flags
;
5816 * All io need record the previous position, if LINK vs DARIN,
5817 * it can be used to mark the position of the first IO in the
5820 req
->sequence
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5821 req
->opcode
= READ_ONCE(sqe
->opcode
);
5822 req
->user_data
= READ_ONCE(sqe
->user_data
);
5827 /* one is dropped after submission, the other at completion */
5828 refcount_set(&req
->refs
, 2);
5831 req
->needs_fixed_file
= async
;
5832 INIT_IO_WORK(&req
->work
, io_wq_submit_work
);
5834 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
5837 if (io_op_defs
[req
->opcode
].needs_mm
&& !current
->mm
) {
5838 if (unlikely(!mmget_not_zero(ctx
->sqo_mm
)))
5840 use_mm(ctx
->sqo_mm
);
5843 sqe_flags
= READ_ONCE(sqe
->flags
);
5844 /* enforce forwards compatibility on users */
5845 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
5848 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
5849 !io_op_defs
[req
->opcode
].buffer_select
)
5852 id
= READ_ONCE(sqe
->personality
);
5854 req
->work
.creds
= idr_find(&ctx
->personality_idr
, id
);
5855 if (unlikely(!req
->work
.creds
))
5857 get_cred(req
->work
.creds
);
5860 /* same numerical values with corresponding REQ_F_*, safe to copy */
5861 req
->flags
|= sqe_flags
& (IOSQE_IO_DRAIN
| IOSQE_IO_HARDLINK
|
5862 IOSQE_ASYNC
| IOSQE_FIXED_FILE
|
5863 IOSQE_BUFFER_SELECT
| IOSQE_IO_LINK
);
5865 fd
= READ_ONCE(sqe
->fd
);
5866 return io_req_set_file(state
, req
, fd
, sqe_flags
);
5869 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
,
5870 struct file
*ring_file
, int ring_fd
, bool async
)
5872 struct io_submit_state state
, *statep
= NULL
;
5873 struct io_kiocb
*link
= NULL
;
5874 int i
, submitted
= 0;
5876 /* if we have a backlog and couldn't flush it all, return BUSY */
5877 if (test_bit(0, &ctx
->sq_check_overflow
)) {
5878 if (!list_empty(&ctx
->cq_overflow_list
) &&
5879 !io_cqring_overflow_flush(ctx
, false))
5883 /* make sure SQ entry isn't read before tail */
5884 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
5886 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
5889 if (nr
> IO_PLUG_THRESHOLD
) {
5890 io_submit_state_start(&state
, nr
);
5894 ctx
->ring_fd
= ring_fd
;
5895 ctx
->ring_file
= ring_file
;
5897 for (i
= 0; i
< nr
; i
++) {
5898 const struct io_uring_sqe
*sqe
;
5899 struct io_kiocb
*req
;
5902 sqe
= io_get_sqe(ctx
);
5903 if (unlikely(!sqe
)) {
5904 io_consume_sqe(ctx
);
5907 req
= io_alloc_req(ctx
, statep
);
5908 if (unlikely(!req
)) {
5910 submitted
= -EAGAIN
;
5914 err
= io_init_req(ctx
, req
, sqe
, statep
, async
);
5915 io_consume_sqe(ctx
);
5916 /* will complete beyond this point, count as submitted */
5919 if (unlikely(err
)) {
5921 io_cqring_add_event(req
, err
);
5922 io_double_put_req(req
);
5926 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
5928 err
= io_submit_sqe(req
, sqe
, statep
, &link
);
5933 if (unlikely(submitted
!= nr
)) {
5934 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
5936 percpu_ref_put_many(&ctx
->refs
, nr
- ref_used
);
5939 io_queue_link_head(link
);
5941 io_submit_state_end(&state
);
5943 /* Commit SQ ring head once we've consumed and submitted all SQEs */
5944 io_commit_sqring(ctx
);
5949 static inline void io_sq_thread_drop_mm(struct io_ring_ctx
*ctx
)
5951 struct mm_struct
*mm
= current
->mm
;
5959 static int io_sq_thread(void *data
)
5961 struct io_ring_ctx
*ctx
= data
;
5962 const struct cred
*old_cred
;
5963 mm_segment_t old_fs
;
5965 unsigned long timeout
;
5968 complete(&ctx
->completions
[1]);
5972 old_cred
= override_creds(ctx
->creds
);
5974 timeout
= jiffies
+ ctx
->sq_thread_idle
;
5975 while (!kthread_should_park()) {
5976 unsigned int to_submit
;
5978 if (!list_empty(&ctx
->poll_list
)) {
5979 unsigned nr_events
= 0;
5981 mutex_lock(&ctx
->uring_lock
);
5982 if (!list_empty(&ctx
->poll_list
))
5983 io_iopoll_getevents(ctx
, &nr_events
, 0);
5985 timeout
= jiffies
+ ctx
->sq_thread_idle
;
5986 mutex_unlock(&ctx
->uring_lock
);
5989 to_submit
= io_sqring_entries(ctx
);
5992 * If submit got -EBUSY, flag us as needing the application
5993 * to enter the kernel to reap and flush events.
5995 if (!to_submit
|| ret
== -EBUSY
) {
5997 * Drop cur_mm before scheduling, we can't hold it for
5998 * long periods (or over schedule()). Do this before
5999 * adding ourselves to the waitqueue, as the unuse/drop
6002 io_sq_thread_drop_mm(ctx
);
6005 * We're polling. If we're within the defined idle
6006 * period, then let us spin without work before going
6007 * to sleep. The exception is if we got EBUSY doing
6008 * more IO, we should wait for the application to
6009 * reap events and wake us up.
6011 if (!list_empty(&ctx
->poll_list
) ||
6012 (!time_after(jiffies
, timeout
) && ret
!= -EBUSY
&&
6013 !percpu_ref_is_dying(&ctx
->refs
))) {
6014 if (current
->task_works
)
6020 prepare_to_wait(&ctx
->sqo_wait
, &wait
,
6021 TASK_INTERRUPTIBLE
);
6024 * While doing polled IO, before going to sleep, we need
6025 * to check if there are new reqs added to poll_list, it
6026 * is because reqs may have been punted to io worker and
6027 * will be added to poll_list later, hence check the
6030 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6031 !list_empty_careful(&ctx
->poll_list
)) {
6032 finish_wait(&ctx
->sqo_wait
, &wait
);
6036 /* Tell userspace we may need a wakeup call */
6037 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6038 /* make sure to read SQ tail after writing flags */
6041 to_submit
= io_sqring_entries(ctx
);
6042 if (!to_submit
|| ret
== -EBUSY
) {
6043 if (kthread_should_park()) {
6044 finish_wait(&ctx
->sqo_wait
, &wait
);
6047 if (current
->task_works
) {
6049 finish_wait(&ctx
->sqo_wait
, &wait
);
6052 if (signal_pending(current
))
6053 flush_signals(current
);
6055 finish_wait(&ctx
->sqo_wait
, &wait
);
6057 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6060 finish_wait(&ctx
->sqo_wait
, &wait
);
6062 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6065 mutex_lock(&ctx
->uring_lock
);
6066 ret
= io_submit_sqes(ctx
, to_submit
, NULL
, -1, true);
6067 mutex_unlock(&ctx
->uring_lock
);
6068 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6071 if (current
->task_works
)
6075 io_sq_thread_drop_mm(ctx
);
6076 revert_creds(old_cred
);
6083 struct io_wait_queue
{
6084 struct wait_queue_entry wq
;
6085 struct io_ring_ctx
*ctx
;
6087 unsigned nr_timeouts
;
6090 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
6092 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6095 * Wake up if we have enough events, or if a timeout occurred since we
6096 * started waiting. For timeouts, we always want to return to userspace,
6097 * regardless of event count.
6099 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
6100 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6103 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6104 int wake_flags
, void *key
)
6106 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6109 /* use noflush == true, as we can't safely rely on locking context */
6110 if (!io_should_wake(iowq
, true))
6113 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6117 * Wait until events become available, if we don't already have some. The
6118 * application must reap them itself, as they reside on the shared cq ring.
6120 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6121 const sigset_t __user
*sig
, size_t sigsz
)
6123 struct io_wait_queue iowq
= {
6126 .func
= io_wake_function
,
6127 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6130 .to_wait
= min_events
,
6132 struct io_rings
*rings
= ctx
->rings
;
6136 if (io_cqring_events(ctx
, false) >= min_events
)
6138 if (!current
->task_works
)
6144 #ifdef CONFIG_COMPAT
6145 if (in_compat_syscall())
6146 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6150 ret
= set_user_sigmask(sig
, sigsz
);
6156 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6157 trace_io_uring_cqring_wait(ctx
, min_events
);
6159 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
6160 TASK_INTERRUPTIBLE
);
6161 if (current
->task_works
)
6163 if (io_should_wake(&iowq
, false))
6166 if (signal_pending(current
)) {
6171 finish_wait(&ctx
->wait
, &iowq
.wq
);
6173 restore_saved_sigmask_unless(ret
== -EINTR
);
6175 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
6178 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6180 #if defined(CONFIG_UNIX)
6181 if (ctx
->ring_sock
) {
6182 struct sock
*sock
= ctx
->ring_sock
->sk
;
6183 struct sk_buff
*skb
;
6185 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
6191 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6194 file
= io_file_from_index(ctx
, i
);
6201 static void io_file_ref_kill(struct percpu_ref
*ref
)
6203 struct fixed_file_data
*data
;
6205 data
= container_of(ref
, struct fixed_file_data
, refs
);
6206 complete(&data
->done
);
6209 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6211 struct fixed_file_data
*data
= ctx
->file_data
;
6212 struct fixed_file_ref_node
*ref_node
= NULL
;
6213 unsigned nr_tables
, i
;
6214 unsigned long flags
;
6219 spin_lock_irqsave(&data
->lock
, flags
);
6220 if (!list_empty(&data
->ref_list
))
6221 ref_node
= list_first_entry(&data
->ref_list
,
6222 struct fixed_file_ref_node
, node
);
6223 spin_unlock_irqrestore(&data
->lock
, flags
);
6225 percpu_ref_kill(&ref_node
->refs
);
6227 percpu_ref_kill(&data
->refs
);
6229 /* wait for all refs nodes to complete */
6230 wait_for_completion(&data
->done
);
6232 __io_sqe_files_unregister(ctx
);
6233 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
6234 for (i
= 0; i
< nr_tables
; i
++)
6235 kfree(data
->table
[i
].files
);
6237 percpu_ref_exit(&data
->refs
);
6239 ctx
->file_data
= NULL
;
6240 ctx
->nr_user_files
= 0;
6244 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
6246 if (ctx
->sqo_thread
) {
6247 wait_for_completion(&ctx
->completions
[1]);
6249 * The park is a bit of a work-around, without it we get
6250 * warning spews on shutdown with SQPOLL set and affinity
6251 * set to a single CPU.
6253 kthread_park(ctx
->sqo_thread
);
6254 kthread_stop(ctx
->sqo_thread
);
6255 ctx
->sqo_thread
= NULL
;
6259 static void io_finish_async(struct io_ring_ctx
*ctx
)
6261 io_sq_thread_stop(ctx
);
6264 io_wq_destroy(ctx
->io_wq
);
6269 #if defined(CONFIG_UNIX)
6271 * Ensure the UNIX gc is aware of our file set, so we are certain that
6272 * the io_uring can be safely unregistered on process exit, even if we have
6273 * loops in the file referencing.
6275 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
6277 struct sock
*sk
= ctx
->ring_sock
->sk
;
6278 struct scm_fp_list
*fpl
;
6279 struct sk_buff
*skb
;
6282 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
6286 skb
= alloc_skb(0, GFP_KERNEL
);
6295 fpl
->user
= get_uid(ctx
->user
);
6296 for (i
= 0; i
< nr
; i
++) {
6297 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
6301 fpl
->fp
[nr_files
] = get_file(file
);
6302 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
6307 fpl
->max
= SCM_MAX_FD
;
6308 fpl
->count
= nr_files
;
6309 UNIXCB(skb
).fp
= fpl
;
6310 skb
->destructor
= unix_destruct_scm
;
6311 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
6312 skb_queue_head(&sk
->sk_receive_queue
, skb
);
6314 for (i
= 0; i
< nr_files
; i
++)
6325 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
6326 * causes regular reference counting to break down. We rely on the UNIX
6327 * garbage collection to take care of this problem for us.
6329 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6331 unsigned left
, total
;
6335 left
= ctx
->nr_user_files
;
6337 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
6339 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
6343 total
+= this_files
;
6349 while (total
< ctx
->nr_user_files
) {
6350 struct file
*file
= io_file_from_index(ctx
, total
);
6360 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6366 static int io_sqe_alloc_file_tables(struct io_ring_ctx
*ctx
, unsigned nr_tables
,
6371 for (i
= 0; i
< nr_tables
; i
++) {
6372 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6373 unsigned this_files
;
6375 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
6376 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
6380 nr_files
-= this_files
;
6386 for (i
= 0; i
< nr_tables
; i
++) {
6387 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6388 kfree(table
->files
);
6393 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
6395 #if defined(CONFIG_UNIX)
6396 struct sock
*sock
= ctx
->ring_sock
->sk
;
6397 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
6398 struct sk_buff
*skb
;
6401 __skb_queue_head_init(&list
);
6404 * Find the skb that holds this file in its SCM_RIGHTS. When found,
6405 * remove this entry and rearrange the file array.
6407 skb
= skb_dequeue(head
);
6409 struct scm_fp_list
*fp
;
6411 fp
= UNIXCB(skb
).fp
;
6412 for (i
= 0; i
< fp
->count
; i
++) {
6415 if (fp
->fp
[i
] != file
)
6418 unix_notinflight(fp
->user
, fp
->fp
[i
]);
6419 left
= fp
->count
- 1 - i
;
6421 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
6422 left
* sizeof(struct file
*));
6429 __skb_queue_tail(&list
, skb
);
6439 __skb_queue_tail(&list
, skb
);
6441 skb
= skb_dequeue(head
);
6444 if (skb_peek(&list
)) {
6445 spin_lock_irq(&head
->lock
);
6446 while ((skb
= __skb_dequeue(&list
)) != NULL
)
6447 __skb_queue_tail(head
, skb
);
6448 spin_unlock_irq(&head
->lock
);
6455 struct io_file_put
{
6456 struct list_head list
;
6460 static void io_file_put_work(struct work_struct
*work
)
6462 struct fixed_file_ref_node
*ref_node
;
6463 struct fixed_file_data
*file_data
;
6464 struct io_ring_ctx
*ctx
;
6465 struct io_file_put
*pfile
, *tmp
;
6466 unsigned long flags
;
6468 ref_node
= container_of(work
, struct fixed_file_ref_node
, work
);
6469 file_data
= ref_node
->file_data
;
6470 ctx
= file_data
->ctx
;
6472 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
6473 list_del_init(&pfile
->list
);
6474 io_ring_file_put(ctx
, pfile
->file
);
6478 spin_lock_irqsave(&file_data
->lock
, flags
);
6479 list_del_init(&ref_node
->node
);
6480 spin_unlock_irqrestore(&file_data
->lock
, flags
);
6482 percpu_ref_exit(&ref_node
->refs
);
6484 percpu_ref_put(&file_data
->refs
);
6487 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
6489 struct fixed_file_ref_node
*ref_node
;
6491 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
6493 queue_work(system_wq
, &ref_node
->work
);
6496 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
6497 struct io_ring_ctx
*ctx
)
6499 struct fixed_file_ref_node
*ref_node
;
6501 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
6503 return ERR_PTR(-ENOMEM
);
6505 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
6508 return ERR_PTR(-ENOMEM
);
6510 INIT_LIST_HEAD(&ref_node
->node
);
6511 INIT_LIST_HEAD(&ref_node
->file_list
);
6512 INIT_WORK(&ref_node
->work
, io_file_put_work
);
6513 ref_node
->file_data
= ctx
->file_data
;
6518 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
6520 percpu_ref_exit(&ref_node
->refs
);
6524 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
6527 __s32 __user
*fds
= (__s32 __user
*) arg
;
6532 struct fixed_file_ref_node
*ref_node
;
6533 unsigned long flags
;
6539 if (nr_args
> IORING_MAX_FIXED_FILES
)
6542 ctx
->file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
6543 if (!ctx
->file_data
)
6545 ctx
->file_data
->ctx
= ctx
;
6546 init_completion(&ctx
->file_data
->done
);
6547 INIT_LIST_HEAD(&ctx
->file_data
->ref_list
);
6548 spin_lock_init(&ctx
->file_data
->lock
);
6550 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
6551 ctx
->file_data
->table
= kcalloc(nr_tables
,
6552 sizeof(struct fixed_file_table
),
6554 if (!ctx
->file_data
->table
) {
6555 kfree(ctx
->file_data
);
6556 ctx
->file_data
= NULL
;
6560 if (percpu_ref_init(&ctx
->file_data
->refs
, io_file_ref_kill
,
6561 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
)) {
6562 kfree(ctx
->file_data
->table
);
6563 kfree(ctx
->file_data
);
6564 ctx
->file_data
= NULL
;
6568 if (io_sqe_alloc_file_tables(ctx
, nr_tables
, nr_args
)) {
6569 percpu_ref_exit(&ctx
->file_data
->refs
);
6570 kfree(ctx
->file_data
->table
);
6571 kfree(ctx
->file_data
);
6572 ctx
->file_data
= NULL
;
6576 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
6577 struct fixed_file_table
*table
;
6581 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
)))
6583 /* allow sparse sets */
6589 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
6590 index
= i
& IORING_FILE_TABLE_MASK
;
6598 * Don't allow io_uring instances to be registered. If UNIX
6599 * isn't enabled, then this causes a reference cycle and this
6600 * instance can never get freed. If UNIX is enabled we'll
6601 * handle it just fine, but there's still no point in allowing
6602 * a ring fd as it doesn't support regular read/write anyway.
6604 if (file
->f_op
== &io_uring_fops
) {
6609 table
->files
[index
] = file
;
6613 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6614 file
= io_file_from_index(ctx
, i
);
6618 for (i
= 0; i
< nr_tables
; i
++)
6619 kfree(ctx
->file_data
->table
[i
].files
);
6621 kfree(ctx
->file_data
->table
);
6622 kfree(ctx
->file_data
);
6623 ctx
->file_data
= NULL
;
6624 ctx
->nr_user_files
= 0;
6628 ret
= io_sqe_files_scm(ctx
);
6630 io_sqe_files_unregister(ctx
);
6634 ref_node
= alloc_fixed_file_ref_node(ctx
);
6635 if (IS_ERR(ref_node
)) {
6636 io_sqe_files_unregister(ctx
);
6637 return PTR_ERR(ref_node
);
6640 ctx
->file_data
->cur_refs
= &ref_node
->refs
;
6641 spin_lock_irqsave(&ctx
->file_data
->lock
, flags
);
6642 list_add(&ref_node
->node
, &ctx
->file_data
->ref_list
);
6643 spin_unlock_irqrestore(&ctx
->file_data
->lock
, flags
);
6644 percpu_ref_get(&ctx
->file_data
->refs
);
6648 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
6651 #if defined(CONFIG_UNIX)
6652 struct sock
*sock
= ctx
->ring_sock
->sk
;
6653 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
6654 struct sk_buff
*skb
;
6657 * See if we can merge this file into an existing skb SCM_RIGHTS
6658 * file set. If there's no room, fall back to allocating a new skb
6659 * and filling it in.
6661 spin_lock_irq(&head
->lock
);
6662 skb
= skb_peek(head
);
6664 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
6666 if (fpl
->count
< SCM_MAX_FD
) {
6667 __skb_unlink(skb
, head
);
6668 spin_unlock_irq(&head
->lock
);
6669 fpl
->fp
[fpl
->count
] = get_file(file
);
6670 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
6672 spin_lock_irq(&head
->lock
);
6673 __skb_queue_head(head
, skb
);
6678 spin_unlock_irq(&head
->lock
);
6685 return __io_sqe_files_scm(ctx
, 1, index
);
6691 static int io_queue_file_removal(struct fixed_file_data
*data
,
6694 struct io_file_put
*pfile
;
6695 struct percpu_ref
*refs
= data
->cur_refs
;
6696 struct fixed_file_ref_node
*ref_node
;
6698 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
6702 ref_node
= container_of(refs
, struct fixed_file_ref_node
, refs
);
6704 list_add(&pfile
->list
, &ref_node
->file_list
);
6709 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
6710 struct io_uring_files_update
*up
,
6713 struct fixed_file_data
*data
= ctx
->file_data
;
6714 struct fixed_file_ref_node
*ref_node
;
6719 unsigned long flags
;
6720 bool needs_switch
= false;
6722 if (check_add_overflow(up
->offset
, nr_args
, &done
))
6724 if (done
> ctx
->nr_user_files
)
6727 ref_node
= alloc_fixed_file_ref_node(ctx
);
6728 if (IS_ERR(ref_node
))
6729 return PTR_ERR(ref_node
);
6732 fds
= u64_to_user_ptr(up
->fds
);
6734 struct fixed_file_table
*table
;
6738 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
6742 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
6743 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
6744 index
= i
& IORING_FILE_TABLE_MASK
;
6745 if (table
->files
[index
]) {
6746 file
= io_file_from_index(ctx
, index
);
6747 err
= io_queue_file_removal(data
, file
);
6750 table
->files
[index
] = NULL
;
6751 needs_switch
= true;
6760 * Don't allow io_uring instances to be registered. If
6761 * UNIX isn't enabled, then this causes a reference
6762 * cycle and this instance can never get freed. If UNIX
6763 * is enabled we'll handle it just fine, but there's
6764 * still no point in allowing a ring fd as it doesn't
6765 * support regular read/write anyway.
6767 if (file
->f_op
== &io_uring_fops
) {
6772 table
->files
[index
] = file
;
6773 err
= io_sqe_file_register(ctx
, file
, i
);
6783 percpu_ref_kill(data
->cur_refs
);
6784 spin_lock_irqsave(&data
->lock
, flags
);
6785 list_add(&ref_node
->node
, &data
->ref_list
);
6786 data
->cur_refs
= &ref_node
->refs
;
6787 spin_unlock_irqrestore(&data
->lock
, flags
);
6788 percpu_ref_get(&ctx
->file_data
->refs
);
6790 destroy_fixed_file_ref_node(ref_node
);
6792 return done
? done
: err
;
6795 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
6798 struct io_uring_files_update up
;
6800 if (!ctx
->file_data
)
6804 if (copy_from_user(&up
, arg
, sizeof(up
)))
6809 return __io_sqe_files_update(ctx
, &up
, nr_args
);
6812 static void io_free_work(struct io_wq_work
*work
)
6814 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6816 /* Consider that io_steal_work() relies on this ref */
6820 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
6821 struct io_uring_params
*p
)
6823 struct io_wq_data data
;
6825 struct io_ring_ctx
*ctx_attach
;
6826 unsigned int concurrency
;
6829 data
.user
= ctx
->user
;
6830 data
.free_work
= io_free_work
;
6832 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
6833 /* Do QD, or 4 * CPUS, whatever is smallest */
6834 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
6836 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
6837 if (IS_ERR(ctx
->io_wq
)) {
6838 ret
= PTR_ERR(ctx
->io_wq
);
6844 f
= fdget(p
->wq_fd
);
6848 if (f
.file
->f_op
!= &io_uring_fops
) {
6853 ctx_attach
= f
.file
->private_data
;
6854 /* @io_wq is protected by holding the fd */
6855 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
6860 ctx
->io_wq
= ctx_attach
->io_wq
;
6866 static int io_sq_offload_start(struct io_ring_ctx
*ctx
,
6867 struct io_uring_params
*p
)
6871 init_waitqueue_head(&ctx
->sqo_wait
);
6872 mmgrab(current
->mm
);
6873 ctx
->sqo_mm
= current
->mm
;
6875 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
6877 if (!capable(CAP_SYS_ADMIN
))
6880 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
6881 if (!ctx
->sq_thread_idle
)
6882 ctx
->sq_thread_idle
= HZ
;
6884 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
6885 int cpu
= p
->sq_thread_cpu
;
6888 if (cpu
>= nr_cpu_ids
)
6890 if (!cpu_online(cpu
))
6893 ctx
->sqo_thread
= kthread_create_on_cpu(io_sq_thread
,
6897 ctx
->sqo_thread
= kthread_create(io_sq_thread
, ctx
,
6900 if (IS_ERR(ctx
->sqo_thread
)) {
6901 ret
= PTR_ERR(ctx
->sqo_thread
);
6902 ctx
->sqo_thread
= NULL
;
6905 wake_up_process(ctx
->sqo_thread
);
6906 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
6907 /* Can't have SQ_AFF without SQPOLL */
6912 ret
= io_init_wq_offload(ctx
, p
);
6918 io_finish_async(ctx
);
6919 mmdrop(ctx
->sqo_mm
);
6924 static void io_unaccount_mem(struct user_struct
*user
, unsigned long nr_pages
)
6926 atomic_long_sub(nr_pages
, &user
->locked_vm
);
6929 static int io_account_mem(struct user_struct
*user
, unsigned long nr_pages
)
6931 unsigned long page_limit
, cur_pages
, new_pages
;
6933 /* Don't allow more pages than we can safely lock */
6934 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
6937 cur_pages
= atomic_long_read(&user
->locked_vm
);
6938 new_pages
= cur_pages
+ nr_pages
;
6939 if (new_pages
> page_limit
)
6941 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
6942 new_pages
) != cur_pages
);
6947 static void io_mem_free(void *ptr
)
6954 page
= virt_to_head_page(ptr
);
6955 if (put_page_testzero(page
))
6956 free_compound_page(page
);
6959 static void *io_mem_alloc(size_t size
)
6961 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
6964 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
6967 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
6970 struct io_rings
*rings
;
6971 size_t off
, sq_array_size
;
6973 off
= struct_size(rings
, cqes
, cq_entries
);
6974 if (off
== SIZE_MAX
)
6978 off
= ALIGN(off
, SMP_CACHE_BYTES
);
6983 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
6984 if (sq_array_size
== SIZE_MAX
)
6987 if (check_add_overflow(off
, sq_array_size
, &off
))
6996 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
7000 pages
= (size_t)1 << get_order(
7001 rings_size(sq_entries
, cq_entries
, NULL
));
7002 pages
+= (size_t)1 << get_order(
7003 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
7008 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
7012 if (!ctx
->user_bufs
)
7015 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7016 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7018 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
7019 unpin_user_page(imu
->bvec
[j
].bv_page
);
7021 if (ctx
->account_mem
)
7022 io_unaccount_mem(ctx
->user
, imu
->nr_bvecs
);
7027 kfree(ctx
->user_bufs
);
7028 ctx
->user_bufs
= NULL
;
7029 ctx
->nr_user_bufs
= 0;
7033 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
7034 void __user
*arg
, unsigned index
)
7036 struct iovec __user
*src
;
7038 #ifdef CONFIG_COMPAT
7040 struct compat_iovec __user
*ciovs
;
7041 struct compat_iovec ciov
;
7043 ciovs
= (struct compat_iovec __user
*) arg
;
7044 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
7047 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
7048 dst
->iov_len
= ciov
.iov_len
;
7052 src
= (struct iovec __user
*) arg
;
7053 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
7058 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7061 struct vm_area_struct
**vmas
= NULL
;
7062 struct page
**pages
= NULL
;
7063 int i
, j
, got_pages
= 0;
7068 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
7071 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
7073 if (!ctx
->user_bufs
)
7076 for (i
= 0; i
< nr_args
; i
++) {
7077 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7078 unsigned long off
, start
, end
, ubuf
;
7083 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
7088 * Don't impose further limits on the size and buffer
7089 * constraints here, we'll -EINVAL later when IO is
7090 * submitted if they are wrong.
7093 if (!iov
.iov_base
|| !iov
.iov_len
)
7096 /* arbitrary limit, but we need something */
7097 if (iov
.iov_len
> SZ_1G
)
7100 ubuf
= (unsigned long) iov
.iov_base
;
7101 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
7102 start
= ubuf
>> PAGE_SHIFT
;
7103 nr_pages
= end
- start
;
7105 if (ctx
->account_mem
) {
7106 ret
= io_account_mem(ctx
->user
, nr_pages
);
7112 if (!pages
|| nr_pages
> got_pages
) {
7115 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
7117 vmas
= kvmalloc_array(nr_pages
,
7118 sizeof(struct vm_area_struct
*),
7120 if (!pages
|| !vmas
) {
7122 if (ctx
->account_mem
)
7123 io_unaccount_mem(ctx
->user
, nr_pages
);
7126 got_pages
= nr_pages
;
7129 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
7133 if (ctx
->account_mem
)
7134 io_unaccount_mem(ctx
->user
, nr_pages
);
7139 down_read(¤t
->mm
->mmap_sem
);
7140 pret
= pin_user_pages(ubuf
, nr_pages
,
7141 FOLL_WRITE
| FOLL_LONGTERM
,
7143 if (pret
== nr_pages
) {
7144 /* don't support file backed memory */
7145 for (j
= 0; j
< nr_pages
; j
++) {
7146 struct vm_area_struct
*vma
= vmas
[j
];
7149 !is_file_hugepages(vma
->vm_file
)) {
7155 ret
= pret
< 0 ? pret
: -EFAULT
;
7157 up_read(¤t
->mm
->mmap_sem
);
7160 * if we did partial map, or found file backed vmas,
7161 * release any pages we did get
7164 unpin_user_pages(pages
, pret
);
7165 if (ctx
->account_mem
)
7166 io_unaccount_mem(ctx
->user
, nr_pages
);
7171 off
= ubuf
& ~PAGE_MASK
;
7173 for (j
= 0; j
< nr_pages
; j
++) {
7176 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
7177 imu
->bvec
[j
].bv_page
= pages
[j
];
7178 imu
->bvec
[j
].bv_len
= vec_len
;
7179 imu
->bvec
[j
].bv_offset
= off
;
7183 /* store original address for later verification */
7185 imu
->len
= iov
.iov_len
;
7186 imu
->nr_bvecs
= nr_pages
;
7188 ctx
->nr_user_bufs
++;
7196 io_sqe_buffer_unregister(ctx
);
7200 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
7202 __s32 __user
*fds
= arg
;
7208 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
7211 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
7212 if (IS_ERR(ctx
->cq_ev_fd
)) {
7213 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
7214 ctx
->cq_ev_fd
= NULL
;
7221 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
7223 if (ctx
->cq_ev_fd
) {
7224 eventfd_ctx_put(ctx
->cq_ev_fd
);
7225 ctx
->cq_ev_fd
= NULL
;
7232 static int __io_destroy_buffers(int id
, void *p
, void *data
)
7234 struct io_ring_ctx
*ctx
= data
;
7235 struct io_buffer
*buf
= p
;
7237 __io_remove_buffers(ctx
, buf
, id
, -1U);
7241 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
7243 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
7244 idr_destroy(&ctx
->io_buffer_idr
);
7247 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
7249 io_finish_async(ctx
);
7251 mmdrop(ctx
->sqo_mm
);
7253 io_iopoll_reap_events(ctx
);
7254 io_sqe_buffer_unregister(ctx
);
7255 io_sqe_files_unregister(ctx
);
7256 io_eventfd_unregister(ctx
);
7257 io_destroy_buffers(ctx
);
7258 idr_destroy(&ctx
->personality_idr
);
7260 #if defined(CONFIG_UNIX)
7261 if (ctx
->ring_sock
) {
7262 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
7263 sock_release(ctx
->ring_sock
);
7267 io_mem_free(ctx
->rings
);
7268 io_mem_free(ctx
->sq_sqes
);
7270 percpu_ref_exit(&ctx
->refs
);
7271 if (ctx
->account_mem
)
7272 io_unaccount_mem(ctx
->user
,
7273 ring_pages(ctx
->sq_entries
, ctx
->cq_entries
));
7274 free_uid(ctx
->user
);
7275 put_cred(ctx
->creds
);
7276 kfree(ctx
->completions
);
7277 kfree(ctx
->cancel_hash
);
7278 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
7282 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
7284 struct io_ring_ctx
*ctx
= file
->private_data
;
7287 poll_wait(file
, &ctx
->cq_wait
, wait
);
7289 * synchronizes with barrier from wq_has_sleeper call in
7293 if (READ_ONCE(ctx
->rings
->sq
.tail
) - ctx
->cached_sq_head
!=
7294 ctx
->rings
->sq_ring_entries
)
7295 mask
|= EPOLLOUT
| EPOLLWRNORM
;
7296 if (io_cqring_events(ctx
, false))
7297 mask
|= EPOLLIN
| EPOLLRDNORM
;
7302 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
7304 struct io_ring_ctx
*ctx
= file
->private_data
;
7306 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
7309 static int io_remove_personalities(int id
, void *p
, void *data
)
7311 struct io_ring_ctx
*ctx
= data
;
7312 const struct cred
*cred
;
7314 cred
= idr_remove(&ctx
->personality_idr
, id
);
7320 static void io_ring_exit_work(struct work_struct
*work
)
7322 struct io_ring_ctx
*ctx
;
7324 ctx
= container_of(work
, struct io_ring_ctx
, exit_work
);
7326 io_cqring_overflow_flush(ctx
, true);
7328 wait_for_completion(&ctx
->completions
[0]);
7329 io_ring_ctx_free(ctx
);
7332 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
7334 mutex_lock(&ctx
->uring_lock
);
7335 percpu_ref_kill(&ctx
->refs
);
7336 mutex_unlock(&ctx
->uring_lock
);
7339 * Wait for sq thread to idle, if we have one. It won't spin on new
7340 * work after we've killed the ctx ref above. This is important to do
7341 * before we cancel existing commands, as the thread could otherwise
7342 * be queueing new work post that. If that's work we need to cancel,
7343 * it could cause shutdown to hang.
7345 while (ctx
->sqo_thread
&& !wq_has_sleeper(&ctx
->sqo_wait
))
7348 io_kill_timeouts(ctx
);
7349 io_poll_remove_all(ctx
);
7352 io_wq_cancel_all(ctx
->io_wq
);
7354 io_iopoll_reap_events(ctx
);
7355 /* if we failed setting up the ctx, we might not have any rings */
7357 io_cqring_overflow_flush(ctx
, true);
7358 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
7359 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
7360 queue_work(system_wq
, &ctx
->exit_work
);
7363 static int io_uring_release(struct inode
*inode
, struct file
*file
)
7365 struct io_ring_ctx
*ctx
= file
->private_data
;
7367 file
->private_data
= NULL
;
7368 io_ring_ctx_wait_and_kill(ctx
);
7372 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
7373 struct files_struct
*files
)
7375 struct io_kiocb
*req
;
7378 while (!list_empty_careful(&ctx
->inflight_list
)) {
7379 struct io_kiocb
*cancel_req
= NULL
;
7381 spin_lock_irq(&ctx
->inflight_lock
);
7382 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
7383 if (req
->work
.files
!= files
)
7385 /* req is being completed, ignore */
7386 if (!refcount_inc_not_zero(&req
->refs
))
7392 prepare_to_wait(&ctx
->inflight_wait
, &wait
,
7393 TASK_UNINTERRUPTIBLE
);
7394 spin_unlock_irq(&ctx
->inflight_lock
);
7396 /* We need to keep going until we don't find a matching req */
7400 if (cancel_req
->flags
& REQ_F_OVERFLOW
) {
7401 spin_lock_irq(&ctx
->completion_lock
);
7402 list_del(&cancel_req
->list
);
7403 cancel_req
->flags
&= ~REQ_F_OVERFLOW
;
7404 if (list_empty(&ctx
->cq_overflow_list
)) {
7405 clear_bit(0, &ctx
->sq_check_overflow
);
7406 clear_bit(0, &ctx
->cq_check_overflow
);
7408 spin_unlock_irq(&ctx
->completion_lock
);
7410 WRITE_ONCE(ctx
->rings
->cq_overflow
,
7411 atomic_inc_return(&ctx
->cached_cq_overflow
));
7414 * Put inflight ref and overflow ref. If that's
7415 * all we had, then we're done with this request.
7417 if (refcount_sub_and_test(2, &cancel_req
->refs
)) {
7418 io_put_req(cancel_req
);
7423 io_wq_cancel_work(ctx
->io_wq
, &cancel_req
->work
);
7424 io_put_req(cancel_req
);
7427 finish_wait(&ctx
->inflight_wait
, &wait
);
7430 static int io_uring_flush(struct file
*file
, void *data
)
7432 struct io_ring_ctx
*ctx
= file
->private_data
;
7434 io_uring_cancel_files(ctx
, data
);
7437 * If the task is going away, cancel work it may have pending
7439 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
))
7440 io_wq_cancel_pid(ctx
->io_wq
, task_pid_vnr(current
));
7445 static void *io_uring_validate_mmap_request(struct file
*file
,
7446 loff_t pgoff
, size_t sz
)
7448 struct io_ring_ctx
*ctx
= file
->private_data
;
7449 loff_t offset
= pgoff
<< PAGE_SHIFT
;
7454 case IORING_OFF_SQ_RING
:
7455 case IORING_OFF_CQ_RING
:
7458 case IORING_OFF_SQES
:
7462 return ERR_PTR(-EINVAL
);
7465 page
= virt_to_head_page(ptr
);
7466 if (sz
> page_size(page
))
7467 return ERR_PTR(-EINVAL
);
7474 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
7476 size_t sz
= vma
->vm_end
- vma
->vm_start
;
7480 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
7482 return PTR_ERR(ptr
);
7484 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
7485 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
7488 #else /* !CONFIG_MMU */
7490 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
7492 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
7495 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
7497 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
7500 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
7501 unsigned long addr
, unsigned long len
,
7502 unsigned long pgoff
, unsigned long flags
)
7506 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
7508 return PTR_ERR(ptr
);
7510 return (unsigned long) ptr
;
7513 #endif /* !CONFIG_MMU */
7515 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
7516 u32
, min_complete
, u32
, flags
, const sigset_t __user
*, sig
,
7519 struct io_ring_ctx
*ctx
;
7524 if (current
->task_works
)
7527 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
))
7535 if (f
.file
->f_op
!= &io_uring_fops
)
7539 ctx
= f
.file
->private_data
;
7540 if (!percpu_ref_tryget(&ctx
->refs
))
7544 * For SQ polling, the thread will do all submissions and completions.
7545 * Just return the requested submit count, and wake the thread if
7549 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7550 if (!list_empty_careful(&ctx
->cq_overflow_list
))
7551 io_cqring_overflow_flush(ctx
, false);
7552 if (flags
& IORING_ENTER_SQ_WAKEUP
)
7553 wake_up(&ctx
->sqo_wait
);
7554 submitted
= to_submit
;
7555 } else if (to_submit
) {
7556 mutex_lock(&ctx
->uring_lock
);
7557 submitted
= io_submit_sqes(ctx
, to_submit
, f
.file
, fd
, false);
7558 mutex_unlock(&ctx
->uring_lock
);
7560 if (submitted
!= to_submit
)
7563 if (flags
& IORING_ENTER_GETEVENTS
) {
7564 unsigned nr_events
= 0;
7566 min_complete
= min(min_complete
, ctx
->cq_entries
);
7569 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
7570 * space applications don't need to do io completion events
7571 * polling again, they can rely on io_sq_thread to do polling
7572 * work, which can reduce cpu usage and uring_lock contention.
7574 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
7575 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
7576 ret
= io_iopoll_check(ctx
, &nr_events
, min_complete
);
7578 ret
= io_cqring_wait(ctx
, min_complete
, sig
, sigsz
);
7583 percpu_ref_put(&ctx
->refs
);
7586 return submitted
? submitted
: ret
;
7589 #ifdef CONFIG_PROC_FS
7590 static int io_uring_show_cred(int id
, void *p
, void *data
)
7592 const struct cred
*cred
= p
;
7593 struct seq_file
*m
= data
;
7594 struct user_namespace
*uns
= seq_user_ns(m
);
7595 struct group_info
*gi
;
7600 seq_printf(m
, "%5d\n", id
);
7601 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
7602 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
7603 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
7604 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
7605 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
7606 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
7607 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
7608 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
7609 seq_puts(m
, "\n\tGroups:\t");
7610 gi
= cred
->group_info
;
7611 for (g
= 0; g
< gi
->ngroups
; g
++) {
7612 seq_put_decimal_ull(m
, g
? " " : "",
7613 from_kgid_munged(uns
, gi
->gid
[g
]));
7615 seq_puts(m
, "\n\tCapEff:\t");
7616 cap
= cred
->cap_effective
;
7617 CAP_FOR_EACH_U32(__capi
)
7618 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
7623 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
7627 mutex_lock(&ctx
->uring_lock
);
7628 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
7629 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7630 struct fixed_file_table
*table
;
7633 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7634 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
7636 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
7638 seq_printf(m
, "%5u: <none>\n", i
);
7640 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
7641 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7642 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
7644 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
7645 (unsigned int) buf
->len
);
7647 if (!idr_is_empty(&ctx
->personality_idr
)) {
7648 seq_printf(m
, "Personalities:\n");
7649 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
7651 seq_printf(m
, "PollList:\n");
7652 spin_lock_irq(&ctx
->completion_lock
);
7653 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
7654 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
7655 struct io_kiocb
*req
;
7657 hlist_for_each_entry(req
, list
, hash_node
)
7658 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
7659 req
->task
->task_works
!= NULL
);
7661 spin_unlock_irq(&ctx
->completion_lock
);
7662 mutex_unlock(&ctx
->uring_lock
);
7665 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
7667 struct io_ring_ctx
*ctx
= f
->private_data
;
7669 if (percpu_ref_tryget(&ctx
->refs
)) {
7670 __io_uring_show_fdinfo(ctx
, m
);
7671 percpu_ref_put(&ctx
->refs
);
7676 static const struct file_operations io_uring_fops
= {
7677 .release
= io_uring_release
,
7678 .flush
= io_uring_flush
,
7679 .mmap
= io_uring_mmap
,
7681 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
7682 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
7684 .poll
= io_uring_poll
,
7685 .fasync
= io_uring_fasync
,
7686 #ifdef CONFIG_PROC_FS
7687 .show_fdinfo
= io_uring_show_fdinfo
,
7691 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
7692 struct io_uring_params
*p
)
7694 struct io_rings
*rings
;
7695 size_t size
, sq_array_offset
;
7697 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
7698 if (size
== SIZE_MAX
)
7701 rings
= io_mem_alloc(size
);
7706 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
7707 rings
->sq_ring_mask
= p
->sq_entries
- 1;
7708 rings
->cq_ring_mask
= p
->cq_entries
- 1;
7709 rings
->sq_ring_entries
= p
->sq_entries
;
7710 rings
->cq_ring_entries
= p
->cq_entries
;
7711 ctx
->sq_mask
= rings
->sq_ring_mask
;
7712 ctx
->cq_mask
= rings
->cq_ring_mask
;
7713 ctx
->sq_entries
= rings
->sq_ring_entries
;
7714 ctx
->cq_entries
= rings
->cq_ring_entries
;
7716 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
7717 if (size
== SIZE_MAX
) {
7718 io_mem_free(ctx
->rings
);
7723 ctx
->sq_sqes
= io_mem_alloc(size
);
7724 if (!ctx
->sq_sqes
) {
7725 io_mem_free(ctx
->rings
);
7734 * Allocate an anonymous fd, this is what constitutes the application
7735 * visible backing of an io_uring instance. The application mmaps this
7736 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
7737 * we have to tie this fd to a socket for file garbage collection purposes.
7739 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
7744 #if defined(CONFIG_UNIX)
7745 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
7751 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
7755 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
7756 O_RDWR
| O_CLOEXEC
);
7759 ret
= PTR_ERR(file
);
7763 #if defined(CONFIG_UNIX)
7764 ctx
->ring_sock
->file
= file
;
7766 fd_install(ret
, file
);
7769 #if defined(CONFIG_UNIX)
7770 sock_release(ctx
->ring_sock
);
7771 ctx
->ring_sock
= NULL
;
7776 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
)
7778 struct user_struct
*user
= NULL
;
7779 struct io_ring_ctx
*ctx
;
7785 if (entries
> IORING_MAX_ENTRIES
) {
7786 if (!(p
->flags
& IORING_SETUP_CLAMP
))
7788 entries
= IORING_MAX_ENTRIES
;
7792 * Use twice as many entries for the CQ ring. It's possible for the
7793 * application to drive a higher depth than the size of the SQ ring,
7794 * since the sqes are only used at submission time. This allows for
7795 * some flexibility in overcommitting a bit. If the application has
7796 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
7797 * of CQ ring entries manually.
7799 p
->sq_entries
= roundup_pow_of_two(entries
);
7800 if (p
->flags
& IORING_SETUP_CQSIZE
) {
7802 * If IORING_SETUP_CQSIZE is set, we do the same roundup
7803 * to a power-of-two, if it isn't already. We do NOT impose
7804 * any cq vs sq ring sizing.
7806 if (p
->cq_entries
< p
->sq_entries
)
7808 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
7809 if (!(p
->flags
& IORING_SETUP_CLAMP
))
7811 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
7813 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
7815 p
->cq_entries
= 2 * p
->sq_entries
;
7818 user
= get_uid(current_user());
7819 account_mem
= !capable(CAP_IPC_LOCK
);
7822 ret
= io_account_mem(user
,
7823 ring_pages(p
->sq_entries
, p
->cq_entries
));
7830 ctx
= io_ring_ctx_alloc(p
);
7833 io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
7838 ctx
->compat
= in_compat_syscall();
7839 ctx
->account_mem
= account_mem
;
7841 ctx
->creds
= get_current_cred();
7843 ret
= io_allocate_scq_urings(ctx
, p
);
7847 ret
= io_sq_offload_start(ctx
, p
);
7851 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
7852 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
7853 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
7854 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
7855 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
7856 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
7857 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
7858 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
7860 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
7861 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
7862 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
7863 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
7864 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
7865 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
7866 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
7869 * Install ring fd as the very last thing, so we don't risk someone
7870 * having closed it before we finish setup
7872 ret
= io_uring_get_fd(ctx
);
7876 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
7877 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
7878 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
;
7879 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
7882 io_ring_ctx_wait_and_kill(ctx
);
7887 * Sets up an aio uring context, and returns the fd. Applications asks for a
7888 * ring size, we return the actual sq/cq ring sizes (among other things) in the
7889 * params structure passed in.
7891 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
7893 struct io_uring_params p
;
7897 if (copy_from_user(&p
, params
, sizeof(p
)))
7899 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
7904 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
7905 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
7906 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
))
7909 ret
= io_uring_create(entries
, &p
);
7913 if (copy_to_user(params
, &p
, sizeof(p
)))
7919 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
7920 struct io_uring_params __user
*, params
)
7922 return io_uring_setup(entries
, params
);
7925 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
7927 struct io_uring_probe
*p
;
7931 size
= struct_size(p
, ops
, nr_args
);
7932 if (size
== SIZE_MAX
)
7934 p
= kzalloc(size
, GFP_KERNEL
);
7939 if (copy_from_user(p
, arg
, size
))
7942 if (memchr_inv(p
, 0, size
))
7945 p
->last_op
= IORING_OP_LAST
- 1;
7946 if (nr_args
> IORING_OP_LAST
)
7947 nr_args
= IORING_OP_LAST
;
7949 for (i
= 0; i
< nr_args
; i
++) {
7951 if (!io_op_defs
[i
].not_supported
)
7952 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
7957 if (copy_to_user(arg
, p
, size
))
7964 static int io_register_personality(struct io_ring_ctx
*ctx
)
7966 const struct cred
*creds
= get_current_cred();
7969 id
= idr_alloc_cyclic(&ctx
->personality_idr
, (void *) creds
, 1,
7970 USHRT_MAX
, GFP_KERNEL
);
7976 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
7978 const struct cred
*old_creds
;
7980 old_creds
= idr_remove(&ctx
->personality_idr
, id
);
7982 put_cred(old_creds
);
7989 static bool io_register_op_must_quiesce(int op
)
7992 case IORING_UNREGISTER_FILES
:
7993 case IORING_REGISTER_FILES_UPDATE
:
7994 case IORING_REGISTER_PROBE
:
7995 case IORING_REGISTER_PERSONALITY
:
7996 case IORING_UNREGISTER_PERSONALITY
:
8003 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
8004 void __user
*arg
, unsigned nr_args
)
8005 __releases(ctx
->uring_lock
)
8006 __acquires(ctx
->uring_lock
)
8011 * We're inside the ring mutex, if the ref is already dying, then
8012 * someone else killed the ctx or is already going through
8013 * io_uring_register().
8015 if (percpu_ref_is_dying(&ctx
->refs
))
8018 if (io_register_op_must_quiesce(opcode
)) {
8019 percpu_ref_kill(&ctx
->refs
);
8022 * Drop uring mutex before waiting for references to exit. If
8023 * another thread is currently inside io_uring_enter() it might
8024 * need to grab the uring_lock to make progress. If we hold it
8025 * here across the drain wait, then we can deadlock. It's safe
8026 * to drop the mutex here, since no new references will come in
8027 * after we've killed the percpu ref.
8029 mutex_unlock(&ctx
->uring_lock
);
8030 ret
= wait_for_completion_interruptible(&ctx
->completions
[0]);
8031 mutex_lock(&ctx
->uring_lock
);
8033 percpu_ref_resurrect(&ctx
->refs
);
8040 case IORING_REGISTER_BUFFERS
:
8041 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
8043 case IORING_UNREGISTER_BUFFERS
:
8047 ret
= io_sqe_buffer_unregister(ctx
);
8049 case IORING_REGISTER_FILES
:
8050 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
8052 case IORING_UNREGISTER_FILES
:
8056 ret
= io_sqe_files_unregister(ctx
);
8058 case IORING_REGISTER_FILES_UPDATE
:
8059 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
8061 case IORING_REGISTER_EVENTFD
:
8062 case IORING_REGISTER_EVENTFD_ASYNC
:
8066 ret
= io_eventfd_register(ctx
, arg
);
8069 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
8070 ctx
->eventfd_async
= 1;
8072 ctx
->eventfd_async
= 0;
8074 case IORING_UNREGISTER_EVENTFD
:
8078 ret
= io_eventfd_unregister(ctx
);
8080 case IORING_REGISTER_PROBE
:
8082 if (!arg
|| nr_args
> 256)
8084 ret
= io_probe(ctx
, arg
, nr_args
);
8086 case IORING_REGISTER_PERSONALITY
:
8090 ret
= io_register_personality(ctx
);
8092 case IORING_UNREGISTER_PERSONALITY
:
8096 ret
= io_unregister_personality(ctx
, nr_args
);
8103 if (io_register_op_must_quiesce(opcode
)) {
8104 /* bring the ctx back to life */
8105 percpu_ref_reinit(&ctx
->refs
);
8107 reinit_completion(&ctx
->completions
[0]);
8112 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
8113 void __user
*, arg
, unsigned int, nr_args
)
8115 struct io_ring_ctx
*ctx
;
8124 if (f
.file
->f_op
!= &io_uring_fops
)
8127 ctx
= f
.file
->private_data
;
8129 mutex_lock(&ctx
->uring_lock
);
8130 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
8131 mutex_unlock(&ctx
->uring_lock
);
8132 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
8133 ctx
->cq_ev_fd
!= NULL
, ret
);
8139 static int __init
io_uring_init(void)
8141 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
8142 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
8143 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
8146 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
8147 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
8148 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
8149 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
8150 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
8151 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
8152 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
8153 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
8154 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
8155 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
8156 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
8157 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
8158 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
8159 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
8160 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
8161 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
8162 BUILD_BUG_SQE_ELEM(28, __u16
, poll_events
);
8163 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
8164 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
8165 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
8166 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
8167 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
8168 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
8169 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
8170 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
8171 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
8172 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
8173 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
8174 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
8175 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
8177 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
8178 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
8179 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
8182 __initcall(io_uring_init
);