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
;
624 struct io_ring_ctx
*ctx
;
625 struct list_head list
;
628 struct task_struct
*task
;
634 struct list_head link_list
;
636 struct list_head inflight_entry
;
638 struct percpu_ref
*fixed_file_refs
;
642 * Only commands that never go async can use the below fields,
643 * obviously. Right now only IORING_OP_POLL_ADD uses them, and
644 * async armed poll handlers for regular commands. The latter
645 * restore the work, if needed.
648 struct callback_head task_work
;
649 struct hlist_node hash_node
;
650 struct async_poll
*apoll
;
652 struct io_wq_work work
;
656 #define IO_PLUG_THRESHOLD 2
657 #define IO_IOPOLL_BATCH 8
659 struct io_submit_state
{
660 struct blk_plug plug
;
663 * io_kiocb alloc cache
665 void *reqs
[IO_IOPOLL_BATCH
];
666 unsigned int free_reqs
;
669 * File reference cache
673 unsigned int has_refs
;
674 unsigned int used_refs
;
675 unsigned int ios_left
;
679 /* needs req->io allocated for deferral/async */
680 unsigned async_ctx
: 1;
681 /* needs current->mm setup, does mm access */
682 unsigned needs_mm
: 1;
683 /* needs req->file assigned */
684 unsigned needs_file
: 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
] = {
790 [IORING_OP_CLOSE
] = {
794 [IORING_OP_FILES_UPDATE
] = {
798 [IORING_OP_STATX
] = {
806 .unbound_nonreg_file
= 1,
810 [IORING_OP_WRITE
] = {
813 .unbound_nonreg_file
= 1,
816 [IORING_OP_FADVISE
] = {
819 [IORING_OP_MADVISE
] = {
825 .unbound_nonreg_file
= 1,
831 .unbound_nonreg_file
= 1,
835 [IORING_OP_OPENAT2
] = {
839 [IORING_OP_EPOLL_CTL
] = {
840 .unbound_nonreg_file
= 1,
843 [IORING_OP_SPLICE
] = {
846 .unbound_nonreg_file
= 1,
848 [IORING_OP_PROVIDE_BUFFERS
] = {},
849 [IORING_OP_REMOVE_BUFFERS
] = {},
852 static void io_wq_submit_work(struct io_wq_work
**workptr
);
853 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
854 static void io_put_req(struct io_kiocb
*req
);
855 static void __io_double_put_req(struct io_kiocb
*req
);
856 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
857 static void io_queue_linked_timeout(struct io_kiocb
*req
);
858 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
859 struct io_uring_files_update
*ip
,
861 static int io_grab_files(struct io_kiocb
*req
);
862 static void io_cleanup_req(struct io_kiocb
*req
);
863 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
864 int fd
, struct file
**out_file
, bool fixed
);
865 static void __io_queue_sqe(struct io_kiocb
*req
,
866 const struct io_uring_sqe
*sqe
);
868 static struct kmem_cache
*req_cachep
;
870 static const struct file_operations io_uring_fops
;
872 struct sock
*io_uring_get_socket(struct file
*file
)
874 #if defined(CONFIG_UNIX)
875 if (file
->f_op
== &io_uring_fops
) {
876 struct io_ring_ctx
*ctx
= file
->private_data
;
878 return ctx
->ring_sock
->sk
;
883 EXPORT_SYMBOL(io_uring_get_socket
);
885 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
887 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
889 complete(&ctx
->completions
[0]);
892 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
894 struct io_ring_ctx
*ctx
;
897 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
901 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
902 if (!ctx
->fallback_req
)
905 ctx
->completions
= kmalloc(2 * sizeof(struct completion
), GFP_KERNEL
);
906 if (!ctx
->completions
)
910 * Use 5 bits less than the max cq entries, that should give us around
911 * 32 entries per hash list if totally full and uniformly spread.
913 hash_bits
= ilog2(p
->cq_entries
);
917 ctx
->cancel_hash_bits
= hash_bits
;
918 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
920 if (!ctx
->cancel_hash
)
922 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
924 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
925 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
928 ctx
->flags
= p
->flags
;
929 init_waitqueue_head(&ctx
->sqo_wait
);
930 init_waitqueue_head(&ctx
->cq_wait
);
931 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
932 init_completion(&ctx
->completions
[0]);
933 init_completion(&ctx
->completions
[1]);
934 idr_init(&ctx
->io_buffer_idr
);
935 idr_init(&ctx
->personality_idr
);
936 mutex_init(&ctx
->uring_lock
);
937 init_waitqueue_head(&ctx
->wait
);
938 spin_lock_init(&ctx
->completion_lock
);
939 INIT_LIST_HEAD(&ctx
->poll_list
);
940 INIT_LIST_HEAD(&ctx
->defer_list
);
941 INIT_LIST_HEAD(&ctx
->timeout_list
);
942 init_waitqueue_head(&ctx
->inflight_wait
);
943 spin_lock_init(&ctx
->inflight_lock
);
944 INIT_LIST_HEAD(&ctx
->inflight_list
);
947 if (ctx
->fallback_req
)
948 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
949 kfree(ctx
->completions
);
950 kfree(ctx
->cancel_hash
);
955 static inline bool __req_need_defer(struct io_kiocb
*req
)
957 struct io_ring_ctx
*ctx
= req
->ctx
;
959 return req
->sequence
!= ctx
->cached_cq_tail
960 + atomic_read(&ctx
->cached_cq_overflow
);
963 static inline bool req_need_defer(struct io_kiocb
*req
)
965 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
))
966 return __req_need_defer(req
);
971 static struct io_kiocb
*io_get_deferred_req(struct io_ring_ctx
*ctx
)
973 struct io_kiocb
*req
;
975 req
= list_first_entry_or_null(&ctx
->defer_list
, struct io_kiocb
, list
);
976 if (req
&& !req_need_defer(req
)) {
977 list_del_init(&req
->list
);
984 static struct io_kiocb
*io_get_timeout_req(struct io_ring_ctx
*ctx
)
986 struct io_kiocb
*req
;
988 req
= list_first_entry_or_null(&ctx
->timeout_list
, struct io_kiocb
, list
);
990 if (req
->flags
& REQ_F_TIMEOUT_NOSEQ
)
992 if (!__req_need_defer(req
)) {
993 list_del_init(&req
->list
);
1001 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1003 struct io_rings
*rings
= ctx
->rings
;
1005 /* order cqe stores with ring update */
1006 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1008 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1009 wake_up_interruptible(&ctx
->cq_wait
);
1010 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1014 static inline void io_req_work_grab_env(struct io_kiocb
*req
,
1015 const struct io_op_def
*def
)
1017 if (!req
->work
.mm
&& def
->needs_mm
) {
1018 mmgrab(current
->mm
);
1019 req
->work
.mm
= current
->mm
;
1021 if (!req
->work
.creds
)
1022 req
->work
.creds
= get_current_cred();
1023 if (!req
->work
.fs
&& def
->needs_fs
) {
1024 spin_lock(¤t
->fs
->lock
);
1025 if (!current
->fs
->in_exec
) {
1026 req
->work
.fs
= current
->fs
;
1027 req
->work
.fs
->users
++;
1029 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1031 spin_unlock(¤t
->fs
->lock
);
1033 if (!req
->work
.task_pid
)
1034 req
->work
.task_pid
= task_pid_vnr(current
);
1037 static inline void io_req_work_drop_env(struct io_kiocb
*req
)
1040 mmdrop(req
->work
.mm
);
1041 req
->work
.mm
= NULL
;
1043 if (req
->work
.creds
) {
1044 put_cred(req
->work
.creds
);
1045 req
->work
.creds
= NULL
;
1048 struct fs_struct
*fs
= req
->work
.fs
;
1050 spin_lock(&req
->work
.fs
->lock
);
1053 spin_unlock(&req
->work
.fs
->lock
);
1059 static inline void io_prep_async_work(struct io_kiocb
*req
,
1060 struct io_kiocb
**link
)
1062 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1064 if (req
->flags
& REQ_F_ISREG
) {
1065 if (def
->hash_reg_file
)
1066 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1068 if (def
->unbound_nonreg_file
)
1069 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1072 io_req_work_grab_env(req
, def
);
1074 *link
= io_prep_linked_timeout(req
);
1077 static inline void io_queue_async_work(struct io_kiocb
*req
)
1079 struct io_ring_ctx
*ctx
= req
->ctx
;
1080 struct io_kiocb
*link
;
1082 io_prep_async_work(req
, &link
);
1084 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1085 &req
->work
, req
->flags
);
1086 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1089 io_queue_linked_timeout(link
);
1092 static void io_kill_timeout(struct io_kiocb
*req
)
1096 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1098 atomic_inc(&req
->ctx
->cq_timeouts
);
1099 list_del_init(&req
->list
);
1100 req
->flags
|= REQ_F_COMP_LOCKED
;
1101 io_cqring_fill_event(req
, 0);
1106 static void io_kill_timeouts(struct io_ring_ctx
*ctx
)
1108 struct io_kiocb
*req
, *tmp
;
1110 spin_lock_irq(&ctx
->completion_lock
);
1111 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, list
)
1112 io_kill_timeout(req
);
1113 spin_unlock_irq(&ctx
->completion_lock
);
1116 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1118 struct io_kiocb
*req
;
1120 while ((req
= io_get_timeout_req(ctx
)) != NULL
)
1121 io_kill_timeout(req
);
1123 __io_commit_cqring(ctx
);
1125 while ((req
= io_get_deferred_req(ctx
)) != NULL
)
1126 io_queue_async_work(req
);
1129 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1131 struct io_rings
*rings
= ctx
->rings
;
1134 tail
= ctx
->cached_cq_tail
;
1136 * writes to the cq entry need to come after reading head; the
1137 * control dependency is enough as we're using WRITE_ONCE to
1140 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1143 ctx
->cached_cq_tail
++;
1144 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1147 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1151 if (!ctx
->eventfd_async
)
1153 return io_wq_current_is_worker();
1156 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1158 if (waitqueue_active(&ctx
->wait
))
1159 wake_up(&ctx
->wait
);
1160 if (waitqueue_active(&ctx
->sqo_wait
))
1161 wake_up(&ctx
->sqo_wait
);
1162 if (io_should_trigger_evfd(ctx
))
1163 eventfd_signal(ctx
->cq_ev_fd
, 1);
1166 /* Returns true if there are no backlogged entries after the flush */
1167 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1169 struct io_rings
*rings
= ctx
->rings
;
1170 struct io_uring_cqe
*cqe
;
1171 struct io_kiocb
*req
;
1172 unsigned long flags
;
1176 if (list_empty_careful(&ctx
->cq_overflow_list
))
1178 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1179 rings
->cq_ring_entries
))
1183 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1185 /* if force is set, the ring is going away. always drop after that */
1187 ctx
->cq_overflow_flushed
= 1;
1190 while (!list_empty(&ctx
->cq_overflow_list
)) {
1191 cqe
= io_get_cqring(ctx
);
1195 req
= list_first_entry(&ctx
->cq_overflow_list
, struct io_kiocb
,
1197 list_move(&req
->list
, &list
);
1198 req
->flags
&= ~REQ_F_OVERFLOW
;
1200 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1201 WRITE_ONCE(cqe
->res
, req
->result
);
1202 WRITE_ONCE(cqe
->flags
, req
->cflags
);
1204 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1205 atomic_inc_return(&ctx
->cached_cq_overflow
));
1209 io_commit_cqring(ctx
);
1211 clear_bit(0, &ctx
->sq_check_overflow
);
1212 clear_bit(0, &ctx
->cq_check_overflow
);
1214 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1215 io_cqring_ev_posted(ctx
);
1217 while (!list_empty(&list
)) {
1218 req
= list_first_entry(&list
, struct io_kiocb
, list
);
1219 list_del(&req
->list
);
1226 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1228 struct io_ring_ctx
*ctx
= req
->ctx
;
1229 struct io_uring_cqe
*cqe
;
1231 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1234 * If we can't get a cq entry, userspace overflowed the
1235 * submission (by quite a lot). Increment the overflow count in
1238 cqe
= io_get_cqring(ctx
);
1240 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1241 WRITE_ONCE(cqe
->res
, res
);
1242 WRITE_ONCE(cqe
->flags
, cflags
);
1243 } else if (ctx
->cq_overflow_flushed
) {
1244 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1245 atomic_inc_return(&ctx
->cached_cq_overflow
));
1247 if (list_empty(&ctx
->cq_overflow_list
)) {
1248 set_bit(0, &ctx
->sq_check_overflow
);
1249 set_bit(0, &ctx
->cq_check_overflow
);
1251 req
->flags
|= REQ_F_OVERFLOW
;
1252 refcount_inc(&req
->refs
);
1254 req
->cflags
= cflags
;
1255 list_add_tail(&req
->list
, &ctx
->cq_overflow_list
);
1259 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1261 __io_cqring_fill_event(req
, res
, 0);
1264 static void __io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1266 struct io_ring_ctx
*ctx
= req
->ctx
;
1267 unsigned long flags
;
1269 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1270 __io_cqring_fill_event(req
, res
, cflags
);
1271 io_commit_cqring(ctx
);
1272 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1274 io_cqring_ev_posted(ctx
);
1277 static void io_cqring_add_event(struct io_kiocb
*req
, long res
)
1279 __io_cqring_add_event(req
, res
, 0);
1282 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1284 return req
== (struct io_kiocb
*)
1285 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1288 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1290 struct io_kiocb
*req
;
1292 req
= ctx
->fallback_req
;
1293 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1299 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1300 struct io_submit_state
*state
)
1302 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1303 struct io_kiocb
*req
;
1306 req
= kmem_cache_alloc(req_cachep
, gfp
);
1309 } else if (!state
->free_reqs
) {
1313 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1314 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1317 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1318 * retry single alloc to be on the safe side.
1320 if (unlikely(ret
<= 0)) {
1321 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1322 if (!state
->reqs
[0])
1326 state
->free_reqs
= ret
- 1;
1327 req
= state
->reqs
[ret
- 1];
1330 req
= state
->reqs
[state
->free_reqs
];
1335 return io_get_fallback_req(ctx
);
1338 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1342 percpu_ref_put(req
->fixed_file_refs
);
1347 static void __io_req_aux_free(struct io_kiocb
*req
)
1349 if (req
->flags
& REQ_F_NEED_CLEANUP
)
1350 io_cleanup_req(req
);
1354 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1356 put_task_struct(req
->task
);
1358 io_req_work_drop_env(req
);
1361 static void __io_free_req(struct io_kiocb
*req
)
1363 __io_req_aux_free(req
);
1365 if (req
->flags
& REQ_F_INFLIGHT
) {
1366 struct io_ring_ctx
*ctx
= req
->ctx
;
1367 unsigned long flags
;
1369 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1370 list_del(&req
->inflight_entry
);
1371 if (waitqueue_active(&ctx
->inflight_wait
))
1372 wake_up(&ctx
->inflight_wait
);
1373 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1376 percpu_ref_put(&req
->ctx
->refs
);
1377 if (likely(!io_is_fallback_req(req
)))
1378 kmem_cache_free(req_cachep
, req
);
1380 clear_bit_unlock(0, (unsigned long *) &req
->ctx
->fallback_req
);
1384 void *reqs
[IO_IOPOLL_BATCH
];
1389 static void io_free_req_many(struct io_ring_ctx
*ctx
, struct req_batch
*rb
)
1393 if (rb
->need_iter
) {
1394 int i
, inflight
= 0;
1395 unsigned long flags
;
1397 for (i
= 0; i
< rb
->to_free
; i
++) {
1398 struct io_kiocb
*req
= rb
->reqs
[i
];
1400 if (req
->flags
& REQ_F_INFLIGHT
)
1402 __io_req_aux_free(req
);
1407 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1408 for (i
= 0; i
< rb
->to_free
; i
++) {
1409 struct io_kiocb
*req
= rb
->reqs
[i
];
1411 if (req
->flags
& REQ_F_INFLIGHT
) {
1412 list_del(&req
->inflight_entry
);
1417 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1419 if (waitqueue_active(&ctx
->inflight_wait
))
1420 wake_up(&ctx
->inflight_wait
);
1423 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
1424 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
1425 rb
->to_free
= rb
->need_iter
= 0;
1428 static bool io_link_cancel_timeout(struct io_kiocb
*req
)
1430 struct io_ring_ctx
*ctx
= req
->ctx
;
1433 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1435 io_cqring_fill_event(req
, -ECANCELED
);
1436 io_commit_cqring(ctx
);
1437 req
->flags
&= ~REQ_F_LINK_HEAD
;
1445 static void io_req_link_next(struct io_kiocb
*req
, struct io_kiocb
**nxtptr
)
1447 struct io_ring_ctx
*ctx
= req
->ctx
;
1448 bool wake_ev
= false;
1450 /* Already got next link */
1451 if (req
->flags
& REQ_F_LINK_NEXT
)
1455 * The list should never be empty when we are called here. But could
1456 * potentially happen if the chain is messed up, check to be on the
1459 while (!list_empty(&req
->link_list
)) {
1460 struct io_kiocb
*nxt
= list_first_entry(&req
->link_list
,
1461 struct io_kiocb
, link_list
);
1463 if (unlikely((req
->flags
& REQ_F_LINK_TIMEOUT
) &&
1464 (nxt
->flags
& REQ_F_TIMEOUT
))) {
1465 list_del_init(&nxt
->link_list
);
1466 wake_ev
|= io_link_cancel_timeout(nxt
);
1467 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1471 list_del_init(&req
->link_list
);
1472 if (!list_empty(&nxt
->link_list
))
1473 nxt
->flags
|= REQ_F_LINK_HEAD
;
1478 req
->flags
|= REQ_F_LINK_NEXT
;
1480 io_cqring_ev_posted(ctx
);
1484 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
1486 static void io_fail_links(struct io_kiocb
*req
)
1488 struct io_ring_ctx
*ctx
= req
->ctx
;
1489 unsigned long flags
;
1491 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1493 while (!list_empty(&req
->link_list
)) {
1494 struct io_kiocb
*link
= list_first_entry(&req
->link_list
,
1495 struct io_kiocb
, link_list
);
1497 list_del_init(&link
->link_list
);
1498 trace_io_uring_fail_link(req
, link
);
1500 if ((req
->flags
& REQ_F_LINK_TIMEOUT
) &&
1501 link
->opcode
== IORING_OP_LINK_TIMEOUT
) {
1502 io_link_cancel_timeout(link
);
1504 io_cqring_fill_event(link
, -ECANCELED
);
1505 __io_double_put_req(link
);
1507 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1510 io_commit_cqring(ctx
);
1511 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1512 io_cqring_ev_posted(ctx
);
1515 static void io_req_find_next(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
1517 if (likely(!(req
->flags
& REQ_F_LINK_HEAD
)))
1521 * If LINK is set, we have dependent requests in this chain. If we
1522 * didn't fail this request, queue the first one up, moving any other
1523 * dependencies to the next request. In case of failure, fail the rest
1526 if (req
->flags
& REQ_F_FAIL_LINK
) {
1528 } else if ((req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_COMP_LOCKED
)) ==
1529 REQ_F_LINK_TIMEOUT
) {
1530 struct io_ring_ctx
*ctx
= req
->ctx
;
1531 unsigned long flags
;
1534 * If this is a timeout link, we could be racing with the
1535 * timeout timer. Grab the completion lock for this case to
1536 * protect against that.
1538 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1539 io_req_link_next(req
, nxt
);
1540 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1542 io_req_link_next(req
, nxt
);
1546 static void io_free_req(struct io_kiocb
*req
)
1548 struct io_kiocb
*nxt
= NULL
;
1550 io_req_find_next(req
, &nxt
);
1554 io_queue_async_work(nxt
);
1557 static void io_link_work_cb(struct io_wq_work
**workptr
)
1559 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
1560 struct io_kiocb
*link
;
1562 link
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1563 io_queue_linked_timeout(link
);
1564 io_wq_submit_work(workptr
);
1567 static void io_wq_assign_next(struct io_wq_work
**workptr
, struct io_kiocb
*nxt
)
1569 struct io_kiocb
*link
;
1570 const struct io_op_def
*def
= &io_op_defs
[nxt
->opcode
];
1572 if ((nxt
->flags
& REQ_F_ISREG
) && def
->hash_reg_file
)
1573 io_wq_hash_work(&nxt
->work
, file_inode(nxt
->file
));
1575 *workptr
= &nxt
->work
;
1576 link
= io_prep_linked_timeout(nxt
);
1578 nxt
->work
.func
= io_link_work_cb
;
1582 * Drop reference to request, return next in chain (if there is one) if this
1583 * was the last reference to this request.
1585 __attribute__((nonnull
))
1586 static void io_put_req_find_next(struct io_kiocb
*req
, struct io_kiocb
**nxtptr
)
1588 if (refcount_dec_and_test(&req
->refs
)) {
1589 io_req_find_next(req
, nxtptr
);
1594 static void io_put_req(struct io_kiocb
*req
)
1596 if (refcount_dec_and_test(&req
->refs
))
1600 static void io_steal_work(struct io_kiocb
*req
,
1601 struct io_wq_work
**workptr
)
1604 * It's in an io-wq worker, so there always should be at least
1605 * one reference, which will be dropped in io_put_work() just
1606 * after the current handler returns.
1608 * It also means, that if the counter dropped to 1, then there is
1609 * no asynchronous users left, so it's safe to steal the next work.
1611 if (refcount_read(&req
->refs
) == 1) {
1612 struct io_kiocb
*nxt
= NULL
;
1614 io_req_find_next(req
, &nxt
);
1616 io_wq_assign_next(workptr
, nxt
);
1621 * Must only be used if we don't need to care about links, usually from
1622 * within the completion handling itself.
1624 static void __io_double_put_req(struct io_kiocb
*req
)
1626 /* drop both submit and complete references */
1627 if (refcount_sub_and_test(2, &req
->refs
))
1631 static void io_double_put_req(struct io_kiocb
*req
)
1633 /* drop both submit and complete references */
1634 if (refcount_sub_and_test(2, &req
->refs
))
1638 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
1640 struct io_rings
*rings
= ctx
->rings
;
1642 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1644 * noflush == true is from the waitqueue handler, just ensure
1645 * we wake up the task, and the next invocation will flush the
1646 * entries. We cannot safely to it from here.
1648 if (noflush
&& !list_empty(&ctx
->cq_overflow_list
))
1651 io_cqring_overflow_flush(ctx
, false);
1654 /* See comment at the top of this file */
1656 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
1659 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
1661 struct io_rings
*rings
= ctx
->rings
;
1663 /* make sure SQ entry isn't read before tail */
1664 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
1667 static inline bool io_req_multi_free(struct req_batch
*rb
, struct io_kiocb
*req
)
1669 if ((req
->flags
& REQ_F_LINK_HEAD
) || io_is_fallback_req(req
))
1672 if (req
->file
|| req
->io
)
1675 rb
->reqs
[rb
->to_free
++] = req
;
1676 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
1677 io_free_req_many(req
->ctx
, rb
);
1681 static int io_put_kbuf(struct io_kiocb
*req
)
1683 struct io_buffer
*kbuf
;
1686 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
1687 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
1688 cflags
|= IORING_CQE_F_BUFFER
;
1695 * Find and free completed poll iocbs
1697 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1698 struct list_head
*done
)
1700 struct req_batch rb
;
1701 struct io_kiocb
*req
;
1703 rb
.to_free
= rb
.need_iter
= 0;
1704 while (!list_empty(done
)) {
1707 req
= list_first_entry(done
, struct io_kiocb
, list
);
1708 list_del(&req
->list
);
1710 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
1711 cflags
= io_put_kbuf(req
);
1713 __io_cqring_fill_event(req
, req
->result
, cflags
);
1716 if (refcount_dec_and_test(&req
->refs
) &&
1717 !io_req_multi_free(&rb
, req
))
1721 io_commit_cqring(ctx
);
1722 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
1723 io_cqring_ev_posted(ctx
);
1724 io_free_req_many(ctx
, &rb
);
1727 static void io_iopoll_queue(struct list_head
*again
)
1729 struct io_kiocb
*req
;
1732 req
= list_first_entry(again
, struct io_kiocb
, list
);
1733 list_del(&req
->list
);
1734 refcount_inc(&req
->refs
);
1735 io_queue_async_work(req
);
1736 } while (!list_empty(again
));
1739 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1742 struct io_kiocb
*req
, *tmp
;
1749 * Only spin for completions if we don't have multiple devices hanging
1750 * off our complete list, and we're under the requested amount.
1752 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
1755 list_for_each_entry_safe(req
, tmp
, &ctx
->poll_list
, list
) {
1756 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
1759 * Move completed and retryable entries to our local lists.
1760 * If we find a request that requires polling, break out
1761 * and complete those lists first, if we have entries there.
1763 if (req
->flags
& REQ_F_IOPOLL_COMPLETED
) {
1764 list_move_tail(&req
->list
, &done
);
1767 if (!list_empty(&done
))
1770 if (req
->result
== -EAGAIN
) {
1771 list_move_tail(&req
->list
, &again
);
1774 if (!list_empty(&again
))
1777 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
1786 if (!list_empty(&done
))
1787 io_iopoll_complete(ctx
, nr_events
, &done
);
1789 if (!list_empty(&again
))
1790 io_iopoll_queue(&again
);
1796 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
1797 * non-spinning poll check - we'll still enter the driver poll loop, but only
1798 * as a non-spinning completion check.
1800 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1803 while (!list_empty(&ctx
->poll_list
) && !need_resched()) {
1806 ret
= io_do_iopoll(ctx
, nr_events
, min
);
1809 if (!min
|| *nr_events
>= min
)
1817 * We can't just wait for polled events to come to us, we have to actively
1818 * find and complete them.
1820 static void io_iopoll_reap_events(struct io_ring_ctx
*ctx
)
1822 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
1825 mutex_lock(&ctx
->uring_lock
);
1826 while (!list_empty(&ctx
->poll_list
)) {
1827 unsigned int nr_events
= 0;
1829 io_iopoll_getevents(ctx
, &nr_events
, 1);
1832 * Ensure we allow local-to-the-cpu processing to take place,
1833 * in this case we need to ensure that we reap all events.
1837 mutex_unlock(&ctx
->uring_lock
);
1840 static int io_iopoll_check(struct io_ring_ctx
*ctx
, unsigned *nr_events
,
1843 int iters
= 0, ret
= 0;
1846 * We disallow the app entering submit/complete with polling, but we
1847 * still need to lock the ring to prevent racing with polled issue
1848 * that got punted to a workqueue.
1850 mutex_lock(&ctx
->uring_lock
);
1855 * Don't enter poll loop if we already have events pending.
1856 * If we do, we can potentially be spinning for commands that
1857 * already triggered a CQE (eg in error).
1859 if (io_cqring_events(ctx
, false))
1863 * If a submit got punted to a workqueue, we can have the
1864 * application entering polling for a command before it gets
1865 * issued. That app will hold the uring_lock for the duration
1866 * of the poll right here, so we need to take a breather every
1867 * now and then to ensure that the issue has a chance to add
1868 * the poll to the issued list. Otherwise we can spin here
1869 * forever, while the workqueue is stuck trying to acquire the
1872 if (!(++iters
& 7)) {
1873 mutex_unlock(&ctx
->uring_lock
);
1874 mutex_lock(&ctx
->uring_lock
);
1877 if (*nr_events
< min
)
1878 tmin
= min
- *nr_events
;
1880 ret
= io_iopoll_getevents(ctx
, nr_events
, tmin
);
1884 } while (min
&& !*nr_events
&& !need_resched());
1886 mutex_unlock(&ctx
->uring_lock
);
1890 static void kiocb_end_write(struct io_kiocb
*req
)
1893 * Tell lockdep we inherited freeze protection from submission
1896 if (req
->flags
& REQ_F_ISREG
) {
1897 struct inode
*inode
= file_inode(req
->file
);
1899 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
1901 file_end_write(req
->file
);
1904 static inline void req_set_fail_links(struct io_kiocb
*req
)
1906 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1907 req
->flags
|= REQ_F_FAIL_LINK
;
1910 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
)
1912 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
1915 if (kiocb
->ki_flags
& IOCB_WRITE
)
1916 kiocb_end_write(req
);
1918 if (res
!= req
->result
)
1919 req_set_fail_links(req
);
1920 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
1921 cflags
= io_put_kbuf(req
);
1922 __io_cqring_add_event(req
, res
, cflags
);
1925 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
1927 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
1929 io_complete_rw_common(kiocb
, res
);
1933 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
1935 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
1937 if (kiocb
->ki_flags
& IOCB_WRITE
)
1938 kiocb_end_write(req
);
1940 if (res
!= req
->result
)
1941 req_set_fail_links(req
);
1944 req
->flags
|= REQ_F_IOPOLL_COMPLETED
;
1948 * After the iocb has been issued, it's safe to be found on the poll list.
1949 * Adding the kiocb to the list AFTER submission ensures that we don't
1950 * find it from a io_iopoll_getevents() thread before the issuer is done
1951 * accessing the kiocb cookie.
1953 static void io_iopoll_req_issued(struct io_kiocb
*req
)
1955 struct io_ring_ctx
*ctx
= req
->ctx
;
1958 * Track whether we have multiple files in our lists. This will impact
1959 * how we do polling eventually, not spinning if we're on potentially
1960 * different devices.
1962 if (list_empty(&ctx
->poll_list
)) {
1963 ctx
->poll_multi_file
= false;
1964 } else if (!ctx
->poll_multi_file
) {
1965 struct io_kiocb
*list_req
;
1967 list_req
= list_first_entry(&ctx
->poll_list
, struct io_kiocb
,
1969 if (list_req
->file
!= req
->file
)
1970 ctx
->poll_multi_file
= true;
1974 * For fast devices, IO may have already completed. If it has, add
1975 * it to the front so we find it first.
1977 if (req
->flags
& REQ_F_IOPOLL_COMPLETED
)
1978 list_add(&req
->list
, &ctx
->poll_list
);
1980 list_add_tail(&req
->list
, &ctx
->poll_list
);
1982 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
1983 wq_has_sleeper(&ctx
->sqo_wait
))
1984 wake_up(&ctx
->sqo_wait
);
1987 static void io_file_put(struct io_submit_state
*state
)
1990 int diff
= state
->has_refs
- state
->used_refs
;
1993 fput_many(state
->file
, diff
);
1999 * Get as many references to a file as we have IOs left in this submission,
2000 * assuming most submissions are for one file, or at least that each file
2001 * has more than one submission.
2003 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2009 if (state
->fd
== fd
) {
2016 state
->file
= fget_many(fd
, state
->ios_left
);
2021 state
->has_refs
= state
->ios_left
;
2022 state
->used_refs
= 1;
2028 * If we tracked the file through the SCM inflight mechanism, we could support
2029 * any file. For now, just ensure that anything potentially problematic is done
2032 static bool io_file_supports_async(struct file
*file
, int rw
)
2034 umode_t mode
= file_inode(file
)->i_mode
;
2036 if (S_ISBLK(mode
) || S_ISCHR(mode
) || S_ISSOCK(mode
))
2038 if (S_ISREG(mode
) && file
->f_op
!= &io_uring_fops
)
2041 if (!(file
->f_mode
& FMODE_NOWAIT
))
2045 return file
->f_op
->read_iter
!= NULL
;
2047 return file
->f_op
->write_iter
!= NULL
;
2050 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2051 bool force_nonblock
)
2053 struct io_ring_ctx
*ctx
= req
->ctx
;
2054 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2058 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2059 req
->flags
|= REQ_F_ISREG
;
2061 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2062 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2063 req
->flags
|= REQ_F_CUR_POS
;
2064 kiocb
->ki_pos
= req
->file
->f_pos
;
2066 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2067 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2068 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2072 ioprio
= READ_ONCE(sqe
->ioprio
);
2074 ret
= ioprio_check_cap(ioprio
);
2078 kiocb
->ki_ioprio
= ioprio
;
2080 kiocb
->ki_ioprio
= get_current_ioprio();
2082 /* don't allow async punt if RWF_NOWAIT was requested */
2083 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) ||
2084 (req
->file
->f_flags
& O_NONBLOCK
))
2085 req
->flags
|= REQ_F_NOWAIT
;
2088 kiocb
->ki_flags
|= IOCB_NOWAIT
;
2090 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2091 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2092 !kiocb
->ki_filp
->f_op
->iopoll
)
2095 kiocb
->ki_flags
|= IOCB_HIPRI
;
2096 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2099 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2101 kiocb
->ki_complete
= io_complete_rw
;
2104 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2105 req
->rw
.len
= READ_ONCE(sqe
->len
);
2106 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2110 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2116 case -ERESTARTNOINTR
:
2117 case -ERESTARTNOHAND
:
2118 case -ERESTART_RESTARTBLOCK
:
2120 * We can't just restart the syscall, since previously
2121 * submitted sqes may already be in progress. Just fail this
2127 kiocb
->ki_complete(kiocb
, ret
, 0);
2131 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
)
2133 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2135 if (req
->flags
& REQ_F_CUR_POS
)
2136 req
->file
->f_pos
= kiocb
->ki_pos
;
2137 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2138 io_complete_rw(kiocb
, ret
, 0);
2140 io_rw_done(kiocb
, ret
);
2143 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2144 struct iov_iter
*iter
)
2146 struct io_ring_ctx
*ctx
= req
->ctx
;
2147 size_t len
= req
->rw
.len
;
2148 struct io_mapped_ubuf
*imu
;
2149 u16 index
, buf_index
;
2153 /* attempt to use fixed buffers without having provided iovecs */
2154 if (unlikely(!ctx
->user_bufs
))
2157 buf_index
= req
->buf_index
;
2158 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2161 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2162 imu
= &ctx
->user_bufs
[index
];
2163 buf_addr
= req
->rw
.addr
;
2166 if (buf_addr
+ len
< buf_addr
)
2168 /* not inside the mapped region */
2169 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2173 * May not be a start of buffer, set size appropriately
2174 * and advance us to the beginning.
2176 offset
= buf_addr
- imu
->ubuf
;
2177 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2181 * Don't use iov_iter_advance() here, as it's really slow for
2182 * using the latter parts of a big fixed buffer - it iterates
2183 * over each segment manually. We can cheat a bit here, because
2186 * 1) it's a BVEC iter, we set it up
2187 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2188 * first and last bvec
2190 * So just find our index, and adjust the iterator afterwards.
2191 * If the offset is within the first bvec (or the whole first
2192 * bvec, just use iov_iter_advance(). This makes it easier
2193 * since we can just skip the first segment, which may not
2194 * be PAGE_SIZE aligned.
2196 const struct bio_vec
*bvec
= imu
->bvec
;
2198 if (offset
<= bvec
->bv_len
) {
2199 iov_iter_advance(iter
, offset
);
2201 unsigned long seg_skip
;
2203 /* skip first vec */
2204 offset
-= bvec
->bv_len
;
2205 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2207 iter
->bvec
= bvec
+ seg_skip
;
2208 iter
->nr_segs
-= seg_skip
;
2209 iter
->count
-= bvec
->bv_len
+ offset
;
2210 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2217 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2220 mutex_unlock(&ctx
->uring_lock
);
2223 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2226 * "Normal" inline submissions always hold the uring_lock, since we
2227 * grab it from the system call. Same is true for the SQPOLL offload.
2228 * The only exception is when we've detached the request and issue it
2229 * from an async worker thread, grab the lock for that case.
2232 mutex_lock(&ctx
->uring_lock
);
2235 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2236 int bgid
, struct io_buffer
*kbuf
,
2239 struct io_buffer
*head
;
2241 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2244 io_ring_submit_lock(req
->ctx
, needs_lock
);
2246 lockdep_assert_held(&req
->ctx
->uring_lock
);
2248 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
2250 if (!list_empty(&head
->list
)) {
2251 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2253 list_del(&kbuf
->list
);
2256 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
2258 if (*len
> kbuf
->len
)
2261 kbuf
= ERR_PTR(-ENOBUFS
);
2264 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2269 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2272 struct io_buffer
*kbuf
;
2275 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2276 bgid
= req
->buf_index
;
2277 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2280 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2281 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2282 return u64_to_user_ptr(kbuf
->addr
);
2285 #ifdef CONFIG_COMPAT
2286 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2289 struct compat_iovec __user
*uiov
;
2290 compat_ssize_t clen
;
2294 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2295 if (!access_ok(uiov
, sizeof(*uiov
)))
2297 if (__get_user(clen
, &uiov
->iov_len
))
2303 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2305 return PTR_ERR(buf
);
2306 iov
[0].iov_base
= buf
;
2307 iov
[0].iov_len
= (compat_size_t
) len
;
2312 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2315 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2319 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
2322 len
= iov
[0].iov_len
;
2325 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2327 return PTR_ERR(buf
);
2328 iov
[0].iov_base
= buf
;
2329 iov
[0].iov_len
= len
;
2333 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2336 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2340 else if (req
->rw
.len
> 1)
2343 #ifdef CONFIG_COMPAT
2344 if (req
->ctx
->compat
)
2345 return io_compat_import(req
, iov
, needs_lock
);
2348 return __io_iov_buffer_select(req
, iov
, needs_lock
);
2351 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
2352 struct iovec
**iovec
, struct iov_iter
*iter
,
2355 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
2356 size_t sqe_len
= req
->rw
.len
;
2360 opcode
= req
->opcode
;
2361 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
2363 return io_import_fixed(req
, rw
, iter
);
2366 /* buffer index only valid with fixed read/write, or buffer select */
2367 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
2370 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
2371 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2372 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
2375 return PTR_ERR(buf
);
2377 req
->rw
.len
= sqe_len
;
2380 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
2382 return ret
< 0 ? ret
: sqe_len
;
2386 struct io_async_rw
*iorw
= &req
->io
->rw
;
2389 iov_iter_init(iter
, rw
, *iovec
, iorw
->nr_segs
, iorw
->size
);
2390 if (iorw
->iov
== iorw
->fast_iov
)
2395 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2396 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
2398 ret
= (*iovec
)->iov_len
;
2399 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
2405 #ifdef CONFIG_COMPAT
2406 if (req
->ctx
->compat
)
2407 return compat_import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
,
2411 return import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
);
2415 * For files that don't have ->read_iter() and ->write_iter(), handle them
2416 * by looping over ->read() or ->write() manually.
2418 static ssize_t
loop_rw_iter(int rw
, struct file
*file
, struct kiocb
*kiocb
,
2419 struct iov_iter
*iter
)
2424 * Don't support polled IO through this interface, and we can't
2425 * support non-blocking either. For the latter, this just causes
2426 * the kiocb to be handled from an async context.
2428 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2430 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2433 while (iov_iter_count(iter
)) {
2437 if (!iov_iter_is_bvec(iter
)) {
2438 iovec
= iov_iter_iovec(iter
);
2440 /* fixed buffers import bvec */
2441 iovec
.iov_base
= kmap(iter
->bvec
->bv_page
)
2443 iovec
.iov_len
= min(iter
->count
,
2444 iter
->bvec
->bv_len
- iter
->iov_offset
);
2448 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
2449 iovec
.iov_len
, &kiocb
->ki_pos
);
2451 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
2452 iovec
.iov_len
, &kiocb
->ki_pos
);
2455 if (iov_iter_is_bvec(iter
))
2456 kunmap(iter
->bvec
->bv_page
);
2464 if (nr
!= iovec
.iov_len
)
2466 iov_iter_advance(iter
, nr
);
2472 static void io_req_map_rw(struct io_kiocb
*req
, ssize_t io_size
,
2473 struct iovec
*iovec
, struct iovec
*fast_iov
,
2474 struct iov_iter
*iter
)
2476 req
->io
->rw
.nr_segs
= iter
->nr_segs
;
2477 req
->io
->rw
.size
= io_size
;
2478 req
->io
->rw
.iov
= iovec
;
2479 if (!req
->io
->rw
.iov
) {
2480 req
->io
->rw
.iov
= req
->io
->rw
.fast_iov
;
2481 if (req
->io
->rw
.iov
!= fast_iov
)
2482 memcpy(req
->io
->rw
.iov
, fast_iov
,
2483 sizeof(struct iovec
) * iter
->nr_segs
);
2485 req
->flags
|= REQ_F_NEED_CLEANUP
;
2489 static inline int __io_alloc_async_ctx(struct io_kiocb
*req
)
2491 req
->io
= kmalloc(sizeof(*req
->io
), GFP_KERNEL
);
2492 return req
->io
== NULL
;
2495 static int io_alloc_async_ctx(struct io_kiocb
*req
)
2497 if (!io_op_defs
[req
->opcode
].async_ctx
)
2500 return __io_alloc_async_ctx(req
);
2503 static int io_setup_async_rw(struct io_kiocb
*req
, ssize_t io_size
,
2504 struct iovec
*iovec
, struct iovec
*fast_iov
,
2505 struct iov_iter
*iter
)
2507 if (!io_op_defs
[req
->opcode
].async_ctx
)
2510 if (__io_alloc_async_ctx(req
))
2513 io_req_map_rw(req
, io_size
, iovec
, fast_iov
, iter
);
2518 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2519 bool force_nonblock
)
2521 struct io_async_ctx
*io
;
2522 struct iov_iter iter
;
2525 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
2529 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
2532 /* either don't need iovec imported or already have it */
2533 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
2537 io
->rw
.iov
= io
->rw
.fast_iov
;
2539 ret
= io_import_iovec(READ
, req
, &io
->rw
.iov
, &iter
, !force_nonblock
);
2544 io_req_map_rw(req
, ret
, io
->rw
.iov
, io
->rw
.fast_iov
, &iter
);
2548 static int io_read(struct io_kiocb
*req
, bool force_nonblock
)
2550 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2551 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2552 struct iov_iter iter
;
2554 ssize_t io_size
, ret
;
2556 ret
= io_import_iovec(READ
, req
, &iovec
, &iter
, !force_nonblock
);
2560 /* Ensure we clear previously set non-block flag */
2561 if (!force_nonblock
)
2562 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
2566 if (req
->flags
& REQ_F_LINK_HEAD
)
2567 req
->result
= io_size
;
2570 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
2571 * we know to async punt it even if it was opened O_NONBLOCK
2573 if (force_nonblock
&& !io_file_supports_async(req
->file
, READ
))
2576 iov_count
= iov_iter_count(&iter
);
2577 ret
= rw_verify_area(READ
, req
->file
, &kiocb
->ki_pos
, iov_count
);
2581 if (req
->file
->f_op
->read_iter
)
2582 ret2
= call_read_iter(req
->file
, kiocb
, &iter
);
2584 ret2
= loop_rw_iter(READ
, req
->file
, kiocb
, &iter
);
2586 /* Catch -EAGAIN return for forced non-blocking submission */
2587 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
2588 kiocb_done(kiocb
, ret2
);
2591 ret
= io_setup_async_rw(req
, io_size
, iovec
,
2592 inline_vecs
, &iter
);
2595 /* any defer here is final, must blocking retry */
2596 if (!(req
->flags
& REQ_F_NOWAIT
) &&
2597 !file_can_poll(req
->file
))
2598 req
->flags
|= REQ_F_MUST_PUNT
;
2604 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2608 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2609 bool force_nonblock
)
2611 struct io_async_ctx
*io
;
2612 struct iov_iter iter
;
2615 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
2619 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
2622 req
->fsize
= rlimit(RLIMIT_FSIZE
);
2624 /* either don't need iovec imported or already have it */
2625 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
2629 io
->rw
.iov
= io
->rw
.fast_iov
;
2631 ret
= io_import_iovec(WRITE
, req
, &io
->rw
.iov
, &iter
, !force_nonblock
);
2636 io_req_map_rw(req
, ret
, io
->rw
.iov
, io
->rw
.fast_iov
, &iter
);
2640 static int io_write(struct io_kiocb
*req
, bool force_nonblock
)
2642 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2643 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2644 struct iov_iter iter
;
2646 ssize_t ret
, io_size
;
2648 ret
= io_import_iovec(WRITE
, req
, &iovec
, &iter
, !force_nonblock
);
2652 /* Ensure we clear previously set non-block flag */
2653 if (!force_nonblock
)
2654 req
->rw
.kiocb
.ki_flags
&= ~IOCB_NOWAIT
;
2658 if (req
->flags
& REQ_F_LINK_HEAD
)
2659 req
->result
= io_size
;
2662 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
2663 * we know to async punt it even if it was opened O_NONBLOCK
2665 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
2668 /* file path doesn't support NOWAIT for non-direct_IO */
2669 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
2670 (req
->flags
& REQ_F_ISREG
))
2673 iov_count
= iov_iter_count(&iter
);
2674 ret
= rw_verify_area(WRITE
, req
->file
, &kiocb
->ki_pos
, iov_count
);
2679 * Open-code file_start_write here to grab freeze protection,
2680 * which will be released by another thread in
2681 * io_complete_rw(). Fool lockdep by telling it the lock got
2682 * released so that it doesn't complain about the held lock when
2683 * we return to userspace.
2685 if (req
->flags
& REQ_F_ISREG
) {
2686 __sb_start_write(file_inode(req
->file
)->i_sb
,
2687 SB_FREEZE_WRITE
, true);
2688 __sb_writers_release(file_inode(req
->file
)->i_sb
,
2691 kiocb
->ki_flags
|= IOCB_WRITE
;
2693 if (!force_nonblock
)
2694 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= req
->fsize
;
2696 if (req
->file
->f_op
->write_iter
)
2697 ret2
= call_write_iter(req
->file
, kiocb
, &iter
);
2699 ret2
= loop_rw_iter(WRITE
, req
->file
, kiocb
, &iter
);
2701 if (!force_nonblock
)
2702 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= RLIM_INFINITY
;
2705 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
2706 * retry them without IOCB_NOWAIT.
2708 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
2710 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
2711 kiocb_done(kiocb
, ret2
);
2714 ret
= io_setup_async_rw(req
, io_size
, iovec
,
2715 inline_vecs
, &iter
);
2718 /* any defer here is final, must blocking retry */
2719 if (!file_can_poll(req
->file
))
2720 req
->flags
|= REQ_F_MUST_PUNT
;
2725 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2730 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2732 struct io_splice
* sp
= &req
->splice
;
2733 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
2736 if (req
->flags
& REQ_F_NEED_CLEANUP
)
2740 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
2741 sp
->off_out
= READ_ONCE(sqe
->off
);
2742 sp
->len
= READ_ONCE(sqe
->len
);
2743 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
2745 if (unlikely(sp
->flags
& ~valid_flags
))
2748 ret
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
), &sp
->file_in
,
2749 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
2752 req
->flags
|= REQ_F_NEED_CLEANUP
;
2754 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
))
2755 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
2760 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
2762 struct io_splice
*sp
= &req
->splice
;
2763 struct file
*in
= sp
->file_in
;
2764 struct file
*out
= sp
->file_out
;
2765 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
2766 loff_t
*poff_in
, *poff_out
;
2772 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
2773 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
2776 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
2778 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
2779 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2781 io_cqring_add_event(req
, ret
);
2783 req_set_fail_links(req
);
2789 * IORING_OP_NOP just posts a completion event, nothing else.
2791 static int io_nop(struct io_kiocb
*req
)
2793 struct io_ring_ctx
*ctx
= req
->ctx
;
2795 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
2798 io_cqring_add_event(req
, 0);
2803 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2805 struct io_ring_ctx
*ctx
= req
->ctx
;
2810 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
2812 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
2815 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
2816 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
2819 req
->sync
.off
= READ_ONCE(sqe
->off
);
2820 req
->sync
.len
= READ_ONCE(sqe
->len
);
2824 static bool io_req_cancelled(struct io_kiocb
*req
)
2826 if (req
->work
.flags
& IO_WQ_WORK_CANCEL
) {
2827 req_set_fail_links(req
);
2828 io_cqring_add_event(req
, -ECANCELED
);
2836 static void __io_fsync(struct io_kiocb
*req
)
2838 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
2841 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
2842 end
> 0 ? end
: LLONG_MAX
,
2843 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
2845 req_set_fail_links(req
);
2846 io_cqring_add_event(req
, ret
);
2850 static void io_fsync_finish(struct io_wq_work
**workptr
)
2852 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
2854 if (io_req_cancelled(req
))
2857 io_steal_work(req
, workptr
);
2860 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
2862 /* fsync always requires a blocking context */
2863 if (force_nonblock
) {
2864 req
->work
.func
= io_fsync_finish
;
2871 static void __io_fallocate(struct io_kiocb
*req
)
2875 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= req
->fsize
;
2876 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
2878 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= RLIM_INFINITY
;
2880 req_set_fail_links(req
);
2881 io_cqring_add_event(req
, ret
);
2885 static void io_fallocate_finish(struct io_wq_work
**workptr
)
2887 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
2889 if (io_req_cancelled(req
))
2891 __io_fallocate(req
);
2892 io_steal_work(req
, workptr
);
2895 static int io_fallocate_prep(struct io_kiocb
*req
,
2896 const struct io_uring_sqe
*sqe
)
2898 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
2901 req
->sync
.off
= READ_ONCE(sqe
->off
);
2902 req
->sync
.len
= READ_ONCE(sqe
->addr
);
2903 req
->sync
.mode
= READ_ONCE(sqe
->len
);
2904 req
->fsize
= rlimit(RLIMIT_FSIZE
);
2908 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
2910 /* fallocate always requiring blocking context */
2911 if (force_nonblock
) {
2912 req
->work
.func
= io_fallocate_finish
;
2916 __io_fallocate(req
);
2920 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2922 const char __user
*fname
;
2925 if (sqe
->ioprio
|| sqe
->buf_index
)
2927 if (req
->flags
& REQ_F_FIXED_FILE
)
2929 if (req
->flags
& REQ_F_NEED_CLEANUP
)
2932 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
2933 req
->open
.how
.mode
= READ_ONCE(sqe
->len
);
2934 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
2935 req
->open
.how
.flags
= READ_ONCE(sqe
->open_flags
);
2936 if (force_o_largefile())
2937 req
->open
.how
.flags
|= O_LARGEFILE
;
2939 req
->open
.filename
= getname(fname
);
2940 if (IS_ERR(req
->open
.filename
)) {
2941 ret
= PTR_ERR(req
->open
.filename
);
2942 req
->open
.filename
= NULL
;
2946 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
2947 req
->flags
|= REQ_F_NEED_CLEANUP
;
2951 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2953 struct open_how __user
*how
;
2954 const char __user
*fname
;
2958 if (sqe
->ioprio
|| sqe
->buf_index
)
2960 if (req
->flags
& REQ_F_FIXED_FILE
)
2962 if (req
->flags
& REQ_F_NEED_CLEANUP
)
2965 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
2966 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
2967 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
2968 len
= READ_ONCE(sqe
->len
);
2970 if (len
< OPEN_HOW_SIZE_VER0
)
2973 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
2978 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
2979 req
->open
.how
.flags
|= O_LARGEFILE
;
2981 req
->open
.filename
= getname(fname
);
2982 if (IS_ERR(req
->open
.filename
)) {
2983 ret
= PTR_ERR(req
->open
.filename
);
2984 req
->open
.filename
= NULL
;
2988 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
2989 req
->flags
|= REQ_F_NEED_CLEANUP
;
2993 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
2995 struct open_flags op
;
3002 ret
= build_open_flags(&req
->open
.how
, &op
);
3006 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3010 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3013 ret
= PTR_ERR(file
);
3015 fsnotify_open(file
);
3016 fd_install(ret
, file
);
3019 putname(req
->open
.filename
);
3020 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3022 req_set_fail_links(req
);
3023 io_cqring_add_event(req
, ret
);
3028 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
3030 req
->open
.how
= build_open_how(req
->open
.how
.flags
, req
->open
.how
.mode
);
3031 return io_openat2(req
, force_nonblock
);
3034 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3035 const struct io_uring_sqe
*sqe
)
3037 struct io_provide_buf
*p
= &req
->pbuf
;
3040 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3043 tmp
= READ_ONCE(sqe
->fd
);
3044 if (!tmp
|| tmp
> USHRT_MAX
)
3047 memset(p
, 0, sizeof(*p
));
3049 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3053 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3054 int bgid
, unsigned nbufs
)
3058 /* shouldn't happen */
3062 /* the head kbuf is the list itself */
3063 while (!list_empty(&buf
->list
)) {
3064 struct io_buffer
*nxt
;
3066 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3067 list_del(&nxt
->list
);
3074 idr_remove(&ctx
->io_buffer_idr
, bgid
);
3079 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
)
3081 struct io_provide_buf
*p
= &req
->pbuf
;
3082 struct io_ring_ctx
*ctx
= req
->ctx
;
3083 struct io_buffer
*head
;
3086 io_ring_submit_lock(ctx
, !force_nonblock
);
3088 lockdep_assert_held(&ctx
->uring_lock
);
3091 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3093 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3095 io_ring_submit_lock(ctx
, !force_nonblock
);
3097 req_set_fail_links(req
);
3098 io_cqring_add_event(req
, ret
);
3103 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3104 const struct io_uring_sqe
*sqe
)
3106 struct io_provide_buf
*p
= &req
->pbuf
;
3109 if (sqe
->ioprio
|| sqe
->rw_flags
)
3112 tmp
= READ_ONCE(sqe
->fd
);
3113 if (!tmp
|| tmp
> USHRT_MAX
)
3116 p
->addr
= READ_ONCE(sqe
->addr
);
3117 p
->len
= READ_ONCE(sqe
->len
);
3119 if (!access_ok(u64_to_user_ptr(p
->addr
), p
->len
))
3122 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3123 tmp
= READ_ONCE(sqe
->off
);
3124 if (tmp
> USHRT_MAX
)
3130 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3132 struct io_buffer
*buf
;
3133 u64 addr
= pbuf
->addr
;
3134 int i
, bid
= pbuf
->bid
;
3136 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3137 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3142 buf
->len
= pbuf
->len
;
3147 INIT_LIST_HEAD(&buf
->list
);
3150 list_add_tail(&buf
->list
, &(*head
)->list
);
3154 return i
? i
: -ENOMEM
;
3157 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
)
3159 struct io_provide_buf
*p
= &req
->pbuf
;
3160 struct io_ring_ctx
*ctx
= req
->ctx
;
3161 struct io_buffer
*head
, *list
;
3164 io_ring_submit_lock(ctx
, !force_nonblock
);
3166 lockdep_assert_held(&ctx
->uring_lock
);
3168 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3170 ret
= io_add_buffers(p
, &head
);
3175 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
3178 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
3183 io_ring_submit_unlock(ctx
, !force_nonblock
);
3185 req_set_fail_links(req
);
3186 io_cqring_add_event(req
, ret
);
3191 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
3192 const struct io_uring_sqe
*sqe
)
3194 #if defined(CONFIG_EPOLL)
3195 if (sqe
->ioprio
|| sqe
->buf_index
)
3198 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
3199 req
->epoll
.op
= READ_ONCE(sqe
->len
);
3200 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
3202 if (ep_op_has_event(req
->epoll
.op
)) {
3203 struct epoll_event __user
*ev
;
3205 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3206 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
3216 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
)
3218 #if defined(CONFIG_EPOLL)
3219 struct io_epoll
*ie
= &req
->epoll
;
3222 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
3223 if (force_nonblock
&& ret
== -EAGAIN
)
3227 req_set_fail_links(req
);
3228 io_cqring_add_event(req
, ret
);
3236 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3238 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3239 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
3242 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
3243 req
->madvise
.len
= READ_ONCE(sqe
->len
);
3244 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3251 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
3253 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3254 struct io_madvise
*ma
= &req
->madvise
;
3260 ret
= do_madvise(ma
->addr
, ma
->len
, ma
->advice
);
3262 req_set_fail_links(req
);
3263 io_cqring_add_event(req
, ret
);
3271 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3273 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
3276 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
3277 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
3278 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3282 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
3284 struct io_fadvise
*fa
= &req
->fadvise
;
3287 if (force_nonblock
) {
3288 switch (fa
->advice
) {
3289 case POSIX_FADV_NORMAL
:
3290 case POSIX_FADV_RANDOM
:
3291 case POSIX_FADV_SEQUENTIAL
:
3298 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
3300 req_set_fail_links(req
);
3301 io_cqring_add_event(req
, ret
);
3306 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3308 const char __user
*fname
;
3309 unsigned lookup_flags
;
3312 if (sqe
->ioprio
|| sqe
->buf_index
)
3314 if (req
->flags
& REQ_F_FIXED_FILE
)
3316 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3319 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3320 req
->open
.mask
= READ_ONCE(sqe
->len
);
3321 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3322 req
->open
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3323 req
->open
.how
.flags
= READ_ONCE(sqe
->statx_flags
);
3325 if (vfs_stat_set_lookup_flags(&lookup_flags
, req
->open
.how
.flags
))
3328 req
->open
.filename
= getname_flags(fname
, lookup_flags
, NULL
);
3329 if (IS_ERR(req
->open
.filename
)) {
3330 ret
= PTR_ERR(req
->open
.filename
);
3331 req
->open
.filename
= NULL
;
3335 req
->flags
|= REQ_F_NEED_CLEANUP
;
3339 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
3341 struct io_open
*ctx
= &req
->open
;
3342 unsigned lookup_flags
;
3347 if (force_nonblock
) {
3348 /* only need file table for an actual valid fd */
3349 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
3350 req
->flags
|= REQ_F_NO_FILE_TABLE
;
3354 if (vfs_stat_set_lookup_flags(&lookup_flags
, ctx
->how
.flags
))
3358 /* filename_lookup() drops it, keep a reference */
3359 ctx
->filename
->refcnt
++;
3361 ret
= filename_lookup(ctx
->dfd
, ctx
->filename
, lookup_flags
, &path
,
3366 ret
= vfs_getattr(&path
, &stat
, ctx
->mask
, ctx
->how
.flags
);
3368 if (retry_estale(ret
, lookup_flags
)) {
3369 lookup_flags
|= LOOKUP_REVAL
;
3373 ret
= cp_statx(&stat
, ctx
->buffer
);
3375 putname(ctx
->filename
);
3376 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3378 req_set_fail_links(req
);
3379 io_cqring_add_event(req
, ret
);
3384 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3387 * If we queue this for async, it must not be cancellable. That would
3388 * leave the 'file' in an undeterminate state.
3390 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
3392 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
3393 sqe
->rw_flags
|| sqe
->buf_index
)
3395 if (req
->flags
& REQ_F_FIXED_FILE
)
3398 req
->close
.fd
= READ_ONCE(sqe
->fd
);
3399 if (req
->file
->f_op
== &io_uring_fops
||
3400 req
->close
.fd
== req
->ctx
->ring_fd
)
3406 /* only called when __close_fd_get_file() is done */
3407 static void __io_close_finish(struct io_kiocb
*req
)
3411 ret
= filp_close(req
->close
.put_file
, req
->work
.files
);
3413 req_set_fail_links(req
);
3414 io_cqring_add_event(req
, ret
);
3415 fput(req
->close
.put_file
);
3419 static void io_close_finish(struct io_wq_work
**workptr
)
3421 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3423 /* not cancellable, don't do io_req_cancelled() */
3424 __io_close_finish(req
);
3425 io_steal_work(req
, workptr
);
3428 static int io_close(struct io_kiocb
*req
, bool force_nonblock
)
3432 req
->close
.put_file
= NULL
;
3433 ret
= __close_fd_get_file(req
->close
.fd
, &req
->close
.put_file
);
3437 /* if the file has a flush method, be safe and punt to async */
3438 if (req
->close
.put_file
->f_op
->flush
&& force_nonblock
) {
3439 /* submission ref will be dropped, take it for async */
3440 refcount_inc(&req
->refs
);
3442 req
->work
.func
= io_close_finish
;
3444 * Do manual async queue here to avoid grabbing files - we don't
3445 * need the files, and it'll cause io_close_finish() to close
3446 * the file again and cause a double CQE entry for this request
3448 io_queue_async_work(req
);
3453 * No ->flush(), safely close from here and just punt the
3454 * fput() to async context.
3456 __io_close_finish(req
);
3460 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3462 struct io_ring_ctx
*ctx
= req
->ctx
;
3467 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3469 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3472 req
->sync
.off
= READ_ONCE(sqe
->off
);
3473 req
->sync
.len
= READ_ONCE(sqe
->len
);
3474 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
3478 static void __io_sync_file_range(struct io_kiocb
*req
)
3482 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
3485 req_set_fail_links(req
);
3486 io_cqring_add_event(req
, ret
);
3491 static void io_sync_file_range_finish(struct io_wq_work
**workptr
)
3493 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3495 if (io_req_cancelled(req
))
3497 __io_sync_file_range(req
);
3498 io_steal_work(req
, workptr
);
3501 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
3503 /* sync_file_range always requires a blocking context */
3504 if (force_nonblock
) {
3505 req
->work
.func
= io_sync_file_range_finish
;
3509 __io_sync_file_range(req
);
3513 #if defined(CONFIG_NET)
3514 static int io_setup_async_msg(struct io_kiocb
*req
,
3515 struct io_async_msghdr
*kmsg
)
3519 if (io_alloc_async_ctx(req
)) {
3520 if (kmsg
->iov
!= kmsg
->fast_iov
)
3524 req
->flags
|= REQ_F_NEED_CLEANUP
;
3525 memcpy(&req
->io
->msg
, kmsg
, sizeof(*kmsg
));
3529 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3531 struct io_sr_msg
*sr
= &req
->sr_msg
;
3532 struct io_async_ctx
*io
= req
->io
;
3535 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
3536 sr
->msg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3537 sr
->len
= READ_ONCE(sqe
->len
);
3539 #ifdef CONFIG_COMPAT
3540 if (req
->ctx
->compat
)
3541 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
3544 if (!io
|| req
->opcode
== IORING_OP_SEND
)
3546 /* iovec is already imported */
3547 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3550 io
->msg
.iov
= io
->msg
.fast_iov
;
3551 ret
= sendmsg_copy_msghdr(&io
->msg
.msg
, sr
->msg
, sr
->msg_flags
,
3554 req
->flags
|= REQ_F_NEED_CLEANUP
;
3558 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
)
3560 struct io_async_msghdr
*kmsg
= NULL
;
3561 struct socket
*sock
;
3564 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3567 sock
= sock_from_file(req
->file
, &ret
);
3569 struct io_async_ctx io
;
3573 kmsg
= &req
->io
->msg
;
3574 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
3575 /* if iov is set, it's allocated already */
3577 kmsg
->iov
= kmsg
->fast_iov
;
3578 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
3580 struct io_sr_msg
*sr
= &req
->sr_msg
;
3583 kmsg
->msg
.msg_name
= &io
.msg
.addr
;
3585 io
.msg
.iov
= io
.msg
.fast_iov
;
3586 ret
= sendmsg_copy_msghdr(&io
.msg
.msg
, sr
->msg
,
3587 sr
->msg_flags
, &io
.msg
.iov
);
3592 flags
= req
->sr_msg
.msg_flags
;
3593 if (flags
& MSG_DONTWAIT
)
3594 req
->flags
|= REQ_F_NOWAIT
;
3595 else if (force_nonblock
)
3596 flags
|= MSG_DONTWAIT
;
3598 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
3599 if (force_nonblock
&& ret
== -EAGAIN
)
3600 return io_setup_async_msg(req
, kmsg
);
3601 if (ret
== -ERESTARTSYS
)
3605 if (kmsg
&& kmsg
->iov
!= kmsg
->fast_iov
)
3607 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3608 io_cqring_add_event(req
, ret
);
3610 req_set_fail_links(req
);
3615 static int io_send(struct io_kiocb
*req
, bool force_nonblock
)
3617 struct socket
*sock
;
3620 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3623 sock
= sock_from_file(req
->file
, &ret
);
3625 struct io_sr_msg
*sr
= &req
->sr_msg
;
3630 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
,
3635 msg
.msg_name
= NULL
;
3636 msg
.msg_control
= NULL
;
3637 msg
.msg_controllen
= 0;
3638 msg
.msg_namelen
= 0;
3640 flags
= req
->sr_msg
.msg_flags
;
3641 if (flags
& MSG_DONTWAIT
)
3642 req
->flags
|= REQ_F_NOWAIT
;
3643 else if (force_nonblock
)
3644 flags
|= MSG_DONTWAIT
;
3646 msg
.msg_flags
= flags
;
3647 ret
= sock_sendmsg(sock
, &msg
);
3648 if (force_nonblock
&& ret
== -EAGAIN
)
3650 if (ret
== -ERESTARTSYS
)
3654 io_cqring_add_event(req
, ret
);
3656 req_set_fail_links(req
);
3661 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
, struct io_async_ctx
*io
)
3663 struct io_sr_msg
*sr
= &req
->sr_msg
;
3664 struct iovec __user
*uiov
;
3668 ret
= __copy_msghdr_from_user(&io
->msg
.msg
, sr
->msg
, &io
->msg
.uaddr
,
3673 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3676 if (copy_from_user(io
->msg
.iov
, uiov
, sizeof(*uiov
)))
3678 sr
->len
= io
->msg
.iov
[0].iov_len
;
3679 iov_iter_init(&io
->msg
.msg
.msg_iter
, READ
, io
->msg
.iov
, 1,
3683 ret
= import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
3684 &io
->msg
.iov
, &io
->msg
.msg
.msg_iter
);
3692 #ifdef CONFIG_COMPAT
3693 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
3694 struct io_async_ctx
*io
)
3696 struct compat_msghdr __user
*msg_compat
;
3697 struct io_sr_msg
*sr
= &req
->sr_msg
;
3698 struct compat_iovec __user
*uiov
;
3703 msg_compat
= (struct compat_msghdr __user
*) sr
->msg
;
3704 ret
= __get_compat_msghdr(&io
->msg
.msg
, msg_compat
, &io
->msg
.uaddr
,
3709 uiov
= compat_ptr(ptr
);
3710 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3711 compat_ssize_t clen
;
3715 if (!access_ok(uiov
, sizeof(*uiov
)))
3717 if (__get_user(clen
, &uiov
->iov_len
))
3721 sr
->len
= io
->msg
.iov
[0].iov_len
;
3724 ret
= compat_import_iovec(READ
, uiov
, len
, UIO_FASTIOV
,
3726 &io
->msg
.msg
.msg_iter
);
3735 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
, struct io_async_ctx
*io
)
3737 io
->msg
.iov
= io
->msg
.fast_iov
;
3739 #ifdef CONFIG_COMPAT
3740 if (req
->ctx
->compat
)
3741 return __io_compat_recvmsg_copy_hdr(req
, io
);
3744 return __io_recvmsg_copy_hdr(req
, io
);
3747 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
3748 int *cflags
, bool needs_lock
)
3750 struct io_sr_msg
*sr
= &req
->sr_msg
;
3751 struct io_buffer
*kbuf
;
3753 if (!(req
->flags
& REQ_F_BUFFER_SELECT
))
3756 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
3761 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3763 *cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
3764 *cflags
|= IORING_CQE_F_BUFFER
;
3768 static int io_recvmsg_prep(struct io_kiocb
*req
,
3769 const struct io_uring_sqe
*sqe
)
3771 struct io_sr_msg
*sr
= &req
->sr_msg
;
3772 struct io_async_ctx
*io
= req
->io
;
3775 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
3776 sr
->msg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3777 sr
->len
= READ_ONCE(sqe
->len
);
3778 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
3780 #ifdef CONFIG_COMPAT
3781 if (req
->ctx
->compat
)
3782 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
3785 if (!io
|| req
->opcode
== IORING_OP_RECV
)
3787 /* iovec is already imported */
3788 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3791 ret
= io_recvmsg_copy_hdr(req
, io
);
3793 req
->flags
|= REQ_F_NEED_CLEANUP
;
3797 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
)
3799 struct io_async_msghdr
*kmsg
= NULL
;
3800 struct socket
*sock
;
3801 int ret
, cflags
= 0;
3803 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3806 sock
= sock_from_file(req
->file
, &ret
);
3808 struct io_buffer
*kbuf
;
3809 struct io_async_ctx io
;
3813 kmsg
= &req
->io
->msg
;
3814 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
3815 /* if iov is set, it's allocated already */
3817 kmsg
->iov
= kmsg
->fast_iov
;
3818 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
3821 kmsg
->msg
.msg_name
= &io
.msg
.addr
;
3823 ret
= io_recvmsg_copy_hdr(req
, &io
);
3828 kbuf
= io_recv_buffer_select(req
, &cflags
, !force_nonblock
);
3830 return PTR_ERR(kbuf
);
3832 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3833 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
3834 1, req
->sr_msg
.len
);
3837 flags
= req
->sr_msg
.msg_flags
;
3838 if (flags
& MSG_DONTWAIT
)
3839 req
->flags
|= REQ_F_NOWAIT
;
3840 else if (force_nonblock
)
3841 flags
|= MSG_DONTWAIT
;
3843 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.msg
,
3844 kmsg
->uaddr
, flags
);
3845 if (force_nonblock
&& ret
== -EAGAIN
)
3846 return io_setup_async_msg(req
, kmsg
);
3847 if (ret
== -ERESTARTSYS
)
3851 if (kmsg
&& kmsg
->iov
!= kmsg
->fast_iov
)
3853 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3854 __io_cqring_add_event(req
, ret
, cflags
);
3856 req_set_fail_links(req
);
3861 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
)
3863 struct io_buffer
*kbuf
= NULL
;
3864 struct socket
*sock
;
3865 int ret
, cflags
= 0;
3867 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3870 sock
= sock_from_file(req
->file
, &ret
);
3872 struct io_sr_msg
*sr
= &req
->sr_msg
;
3873 void __user
*buf
= sr
->buf
;
3878 kbuf
= io_recv_buffer_select(req
, &cflags
, !force_nonblock
);
3880 return PTR_ERR(kbuf
);
3882 buf
= u64_to_user_ptr(kbuf
->addr
);
3884 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
,
3891 req
->flags
|= REQ_F_NEED_CLEANUP
;
3892 msg
.msg_name
= NULL
;
3893 msg
.msg_control
= NULL
;
3894 msg
.msg_controllen
= 0;
3895 msg
.msg_namelen
= 0;
3896 msg
.msg_iocb
= NULL
;
3899 flags
= req
->sr_msg
.msg_flags
;
3900 if (flags
& MSG_DONTWAIT
)
3901 req
->flags
|= REQ_F_NOWAIT
;
3902 else if (force_nonblock
)
3903 flags
|= MSG_DONTWAIT
;
3905 ret
= sock_recvmsg(sock
, &msg
, flags
);
3906 if (force_nonblock
&& ret
== -EAGAIN
)
3908 if (ret
== -ERESTARTSYS
)
3913 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3914 __io_cqring_add_event(req
, ret
, cflags
);
3916 req_set_fail_links(req
);
3921 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3923 struct io_accept
*accept
= &req
->accept
;
3925 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3927 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
3930 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3931 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3932 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
3933 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
3937 static int __io_accept(struct io_kiocb
*req
, bool force_nonblock
)
3939 struct io_accept
*accept
= &req
->accept
;
3940 unsigned file_flags
;
3943 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
3944 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
3945 accept
->addr_len
, accept
->flags
,
3947 if (ret
== -EAGAIN
&& force_nonblock
)
3949 if (ret
== -ERESTARTSYS
)
3952 req_set_fail_links(req
);
3953 io_cqring_add_event(req
, ret
);
3958 static void io_accept_finish(struct io_wq_work
**workptr
)
3960 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3962 if (io_req_cancelled(req
))
3964 __io_accept(req
, false);
3965 io_steal_work(req
, workptr
);
3968 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
)
3972 ret
= __io_accept(req
, force_nonblock
);
3973 if (ret
== -EAGAIN
&& force_nonblock
) {
3974 req
->work
.func
= io_accept_finish
;
3980 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3982 struct io_connect
*conn
= &req
->connect
;
3983 struct io_async_ctx
*io
= req
->io
;
3985 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3987 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
3990 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3991 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
3996 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
3997 &io
->connect
.address
);
4000 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
)
4002 struct io_async_ctx __io
, *io
;
4003 unsigned file_flags
;
4009 ret
= move_addr_to_kernel(req
->connect
.addr
,
4010 req
->connect
.addr_len
,
4011 &__io
.connect
.address
);
4017 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4019 ret
= __sys_connect_file(req
->file
, &io
->connect
.address
,
4020 req
->connect
.addr_len
, file_flags
);
4021 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4024 if (io_alloc_async_ctx(req
)) {
4028 memcpy(&req
->io
->connect
, &__io
.connect
, sizeof(__io
.connect
));
4031 if (ret
== -ERESTARTSYS
)
4035 req_set_fail_links(req
);
4036 io_cqring_add_event(req
, ret
);
4040 #else /* !CONFIG_NET */
4041 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4046 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
)
4051 static int io_send(struct io_kiocb
*req
, bool force_nonblock
)
4056 static int io_recvmsg_prep(struct io_kiocb
*req
,
4057 const struct io_uring_sqe
*sqe
)
4062 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
)
4067 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
)
4072 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4077 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
)
4082 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4087 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
)
4091 #endif /* CONFIG_NET */
4093 struct io_poll_table
{
4094 struct poll_table_struct pt
;
4095 struct io_kiocb
*req
;
4099 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
4100 struct wait_queue_head
*head
)
4102 if (unlikely(poll
->head
)) {
4103 pt
->error
= -EINVAL
;
4109 add_wait_queue(head
, &poll
->wait
);
4112 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4113 struct poll_table_struct
*p
)
4115 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4117 __io_queue_proc(&pt
->req
->apoll
->poll
, pt
, head
);
4120 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4121 __poll_t mask
, task_work_func_t func
)
4123 struct task_struct
*tsk
;
4126 /* for instances that support it check for an event match first: */
4127 if (mask
&& !(mask
& poll
->events
))
4130 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4132 list_del_init(&poll
->wait
.entry
);
4136 init_task_work(&req
->task_work
, func
);
4138 * If this fails, then the task is exiting. When a task exits, the
4139 * work gets canceled, so just cancel this request as well instead
4140 * of executing it. We can't safely execute it anyway, as we may not
4141 * have the needed state needed for it anyway.
4143 ret
= task_work_add(tsk
, &req
->task_work
, true);
4144 if (unlikely(ret
)) {
4145 WRITE_ONCE(poll
->canceled
, true);
4146 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
4147 task_work_add(tsk
, &req
->task_work
, true);
4149 wake_up_process(tsk
);
4153 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4154 __acquires(&req
->ctx
->completion_lock
)
4156 struct io_ring_ctx
*ctx
= req
->ctx
;
4158 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4159 struct poll_table_struct pt
= { ._key
= poll
->events
};
4161 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4164 spin_lock_irq(&ctx
->completion_lock
);
4165 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4166 add_wait_queue(poll
->head
, &poll
->wait
);
4173 static void io_async_task_func(struct callback_head
*cb
)
4175 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4176 struct async_poll
*apoll
= req
->apoll
;
4177 struct io_ring_ctx
*ctx
= req
->ctx
;
4180 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
4182 if (io_poll_rewait(req
, &apoll
->poll
)) {
4183 spin_unlock_irq(&ctx
->completion_lock
);
4187 if (hash_hashed(&req
->hash_node
))
4188 hash_del(&req
->hash_node
);
4190 canceled
= READ_ONCE(apoll
->poll
.canceled
);
4192 io_cqring_fill_event(req
, -ECANCELED
);
4193 io_commit_cqring(ctx
);
4196 spin_unlock_irq(&ctx
->completion_lock
);
4198 /* restore ->work in case we need to retry again */
4199 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4203 io_cqring_ev_posted(ctx
);
4204 req_set_fail_links(req
);
4205 io_double_put_req(req
);
4209 __set_current_state(TASK_RUNNING
);
4210 mutex_lock(&ctx
->uring_lock
);
4211 __io_queue_sqe(req
, NULL
);
4212 mutex_unlock(&ctx
->uring_lock
);
4217 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4220 struct io_kiocb
*req
= wait
->private;
4221 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
4223 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
4226 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
4229 static void io_poll_req_insert(struct io_kiocb
*req
)
4231 struct io_ring_ctx
*ctx
= req
->ctx
;
4232 struct hlist_head
*list
;
4234 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
4235 hlist_add_head(&req
->hash_node
, list
);
4238 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
4239 struct io_poll_iocb
*poll
,
4240 struct io_poll_table
*ipt
, __poll_t mask
,
4241 wait_queue_func_t wake_func
)
4242 __acquires(&ctx
->completion_lock
)
4244 struct io_ring_ctx
*ctx
= req
->ctx
;
4245 bool cancel
= false;
4247 poll
->file
= req
->file
;
4249 poll
->done
= poll
->canceled
= false;
4250 poll
->events
= mask
;
4252 ipt
->pt
._key
= mask
;
4254 ipt
->error
= -EINVAL
;
4256 INIT_LIST_HEAD(&poll
->wait
.entry
);
4257 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
4258 poll
->wait
.private = req
;
4260 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
4262 spin_lock_irq(&ctx
->completion_lock
);
4263 if (likely(poll
->head
)) {
4264 spin_lock(&poll
->head
->lock
);
4265 if (unlikely(list_empty(&poll
->wait
.entry
))) {
4271 if (mask
|| ipt
->error
)
4272 list_del_init(&poll
->wait
.entry
);
4274 WRITE_ONCE(poll
->canceled
, true);
4275 else if (!poll
->done
) /* actually waiting for an event */
4276 io_poll_req_insert(req
);
4277 spin_unlock(&poll
->head
->lock
);
4283 static bool io_arm_poll_handler(struct io_kiocb
*req
)
4285 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
4286 struct io_ring_ctx
*ctx
= req
->ctx
;
4287 struct async_poll
*apoll
;
4288 struct io_poll_table ipt
;
4291 if (!req
->file
|| !file_can_poll(req
->file
))
4293 if (req
->flags
& (REQ_F_MUST_PUNT
| REQ_F_POLLED
))
4295 if (!def
->pollin
&& !def
->pollout
)
4298 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
4299 if (unlikely(!apoll
))
4302 req
->flags
|= REQ_F_POLLED
;
4303 memcpy(&apoll
->work
, &req
->work
, sizeof(req
->work
));
4305 get_task_struct(current
);
4306 req
->task
= current
;
4308 INIT_HLIST_NODE(&req
->hash_node
);
4312 mask
|= POLLIN
| POLLRDNORM
;
4314 mask
|= POLLOUT
| POLLWRNORM
;
4315 mask
|= POLLERR
| POLLPRI
;
4317 ipt
.pt
._qproc
= io_async_queue_proc
;
4319 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
4323 apoll
->poll
.done
= true;
4324 spin_unlock_irq(&ctx
->completion_lock
);
4325 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4329 spin_unlock_irq(&ctx
->completion_lock
);
4330 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
4331 apoll
->poll
.events
);
4335 static bool __io_poll_remove_one(struct io_kiocb
*req
,
4336 struct io_poll_iocb
*poll
)
4338 bool do_complete
= false;
4340 spin_lock(&poll
->head
->lock
);
4341 WRITE_ONCE(poll
->canceled
, true);
4342 if (!list_empty(&poll
->wait
.entry
)) {
4343 list_del_init(&poll
->wait
.entry
);
4346 spin_unlock(&poll
->head
->lock
);
4350 static bool io_poll_remove_one(struct io_kiocb
*req
)
4352 struct async_poll
*apoll
= NULL
;
4355 if (req
->opcode
== IORING_OP_POLL_ADD
) {
4356 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
4359 /* non-poll requests have submit ref still */
4360 do_complete
= __io_poll_remove_one(req
, &req
->apoll
->poll
);
4365 hash_del(&req
->hash_node
);
4367 if (do_complete
&& apoll
) {
4369 * restore ->work because we need to call io_req_work_drop_env.
4371 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4376 io_cqring_fill_event(req
, -ECANCELED
);
4377 io_commit_cqring(req
->ctx
);
4378 req
->flags
|= REQ_F_COMP_LOCKED
;
4385 static void io_poll_remove_all(struct io_ring_ctx
*ctx
)
4387 struct hlist_node
*tmp
;
4388 struct io_kiocb
*req
;
4391 spin_lock_irq(&ctx
->completion_lock
);
4392 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
4393 struct hlist_head
*list
;
4395 list
= &ctx
->cancel_hash
[i
];
4396 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
)
4397 posted
+= io_poll_remove_one(req
);
4399 spin_unlock_irq(&ctx
->completion_lock
);
4402 io_cqring_ev_posted(ctx
);
4405 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
4407 struct hlist_head
*list
;
4408 struct io_kiocb
*req
;
4410 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
4411 hlist_for_each_entry(req
, list
, hash_node
) {
4412 if (sqe_addr
!= req
->user_data
)
4414 if (io_poll_remove_one(req
))
4422 static int io_poll_remove_prep(struct io_kiocb
*req
,
4423 const struct io_uring_sqe
*sqe
)
4425 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4427 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
4431 req
->poll
.addr
= READ_ONCE(sqe
->addr
);
4436 * Find a running poll command that matches one specified in sqe->addr,
4437 * and remove it if found.
4439 static int io_poll_remove(struct io_kiocb
*req
)
4441 struct io_ring_ctx
*ctx
= req
->ctx
;
4445 addr
= req
->poll
.addr
;
4446 spin_lock_irq(&ctx
->completion_lock
);
4447 ret
= io_poll_cancel(ctx
, addr
);
4448 spin_unlock_irq(&ctx
->completion_lock
);
4450 io_cqring_add_event(req
, ret
);
4452 req_set_fail_links(req
);
4457 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4459 struct io_ring_ctx
*ctx
= req
->ctx
;
4461 req
->poll
.done
= true;
4462 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
4463 io_commit_cqring(ctx
);
4466 static void io_poll_task_handler(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
4468 struct io_ring_ctx
*ctx
= req
->ctx
;
4469 struct io_poll_iocb
*poll
= &req
->poll
;
4471 if (io_poll_rewait(req
, poll
)) {
4472 spin_unlock_irq(&ctx
->completion_lock
);
4476 hash_del(&req
->hash_node
);
4477 io_poll_complete(req
, req
->result
, 0);
4478 req
->flags
|= REQ_F_COMP_LOCKED
;
4479 io_put_req_find_next(req
, nxt
);
4480 spin_unlock_irq(&ctx
->completion_lock
);
4482 io_cqring_ev_posted(ctx
);
4485 static void io_poll_task_func(struct callback_head
*cb
)
4487 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4488 struct io_kiocb
*nxt
= NULL
;
4490 io_poll_task_handler(req
, &nxt
);
4492 struct io_ring_ctx
*ctx
= nxt
->ctx
;
4494 mutex_lock(&ctx
->uring_lock
);
4495 __io_queue_sqe(nxt
, NULL
);
4496 mutex_unlock(&ctx
->uring_lock
);
4500 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4503 struct io_kiocb
*req
= wait
->private;
4504 struct io_poll_iocb
*poll
= &req
->poll
;
4506 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
4509 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4510 struct poll_table_struct
*p
)
4512 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4514 __io_queue_proc(&pt
->req
->poll
, pt
, head
);
4517 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4519 struct io_poll_iocb
*poll
= &req
->poll
;
4522 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4524 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
4529 events
= READ_ONCE(sqe
->poll_events
);
4530 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
;
4532 get_task_struct(current
);
4533 req
->task
= current
;
4537 static int io_poll_add(struct io_kiocb
*req
)
4539 struct io_poll_iocb
*poll
= &req
->poll
;
4540 struct io_ring_ctx
*ctx
= req
->ctx
;
4541 struct io_poll_table ipt
;
4544 INIT_HLIST_NODE(&req
->hash_node
);
4545 INIT_LIST_HEAD(&req
->list
);
4546 ipt
.pt
._qproc
= io_poll_queue_proc
;
4548 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
4551 if (mask
) { /* no async, we'd stolen it */
4553 io_poll_complete(req
, mask
, 0);
4555 spin_unlock_irq(&ctx
->completion_lock
);
4558 io_cqring_ev_posted(ctx
);
4564 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
4566 struct io_timeout_data
*data
= container_of(timer
,
4567 struct io_timeout_data
, timer
);
4568 struct io_kiocb
*req
= data
->req
;
4569 struct io_ring_ctx
*ctx
= req
->ctx
;
4570 unsigned long flags
;
4572 atomic_inc(&ctx
->cq_timeouts
);
4574 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4576 * We could be racing with timeout deletion. If the list is empty,
4577 * then timeout lookup already found it and will be handling it.
4579 if (!list_empty(&req
->list
)) {
4580 struct io_kiocb
*prev
;
4583 * Adjust the reqs sequence before the current one because it
4584 * will consume a slot in the cq_ring and the cq_tail
4585 * pointer will be increased, otherwise other timeout reqs may
4586 * return in advance without waiting for enough wait_nr.
4589 list_for_each_entry_continue_reverse(prev
, &ctx
->timeout_list
, list
)
4591 list_del_init(&req
->list
);
4594 io_cqring_fill_event(req
, -ETIME
);
4595 io_commit_cqring(ctx
);
4596 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
4598 io_cqring_ev_posted(ctx
);
4599 req_set_fail_links(req
);
4601 return HRTIMER_NORESTART
;
4604 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
4606 struct io_kiocb
*req
;
4609 list_for_each_entry(req
, &ctx
->timeout_list
, list
) {
4610 if (user_data
== req
->user_data
) {
4611 list_del_init(&req
->list
);
4620 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
4624 req_set_fail_links(req
);
4625 io_cqring_fill_event(req
, -ECANCELED
);
4630 static int io_timeout_remove_prep(struct io_kiocb
*req
,
4631 const struct io_uring_sqe
*sqe
)
4633 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4635 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
4638 req
->timeout
.addr
= READ_ONCE(sqe
->addr
);
4639 req
->timeout
.flags
= READ_ONCE(sqe
->timeout_flags
);
4640 if (req
->timeout
.flags
)
4647 * Remove or update an existing timeout command
4649 static int io_timeout_remove(struct io_kiocb
*req
)
4651 struct io_ring_ctx
*ctx
= req
->ctx
;
4654 spin_lock_irq(&ctx
->completion_lock
);
4655 ret
= io_timeout_cancel(ctx
, req
->timeout
.addr
);
4657 io_cqring_fill_event(req
, ret
);
4658 io_commit_cqring(ctx
);
4659 spin_unlock_irq(&ctx
->completion_lock
);
4660 io_cqring_ev_posted(ctx
);
4662 req_set_fail_links(req
);
4667 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
4668 bool is_timeout_link
)
4670 struct io_timeout_data
*data
;
4673 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4675 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
4677 if (sqe
->off
&& is_timeout_link
)
4679 flags
= READ_ONCE(sqe
->timeout_flags
);
4680 if (flags
& ~IORING_TIMEOUT_ABS
)
4683 req
->timeout
.count
= READ_ONCE(sqe
->off
);
4685 if (!req
->io
&& io_alloc_async_ctx(req
))
4688 data
= &req
->io
->timeout
;
4690 req
->flags
|= REQ_F_TIMEOUT
;
4692 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
4695 if (flags
& IORING_TIMEOUT_ABS
)
4696 data
->mode
= HRTIMER_MODE_ABS
;
4698 data
->mode
= HRTIMER_MODE_REL
;
4700 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
4704 static int io_timeout(struct io_kiocb
*req
)
4706 struct io_ring_ctx
*ctx
= req
->ctx
;
4707 struct io_timeout_data
*data
;
4708 struct list_head
*entry
;
4710 u32 count
= req
->timeout
.count
;
4711 u32 seq
= req
->sequence
;
4713 data
= &req
->io
->timeout
;
4716 * sqe->off holds how many events that need to occur for this
4717 * timeout event to be satisfied. If it isn't set, then this is
4718 * a pure timeout request, sequence isn't used.
4721 req
->flags
|= REQ_F_TIMEOUT_NOSEQ
;
4722 spin_lock_irq(&ctx
->completion_lock
);
4723 entry
= ctx
->timeout_list
.prev
;
4727 req
->sequence
= seq
+ count
;
4730 * Insertion sort, ensuring the first entry in the list is always
4731 * the one we need first.
4733 spin_lock_irq(&ctx
->completion_lock
);
4734 list_for_each_prev(entry
, &ctx
->timeout_list
) {
4735 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
, list
);
4737 long long tmp
, tmp_nxt
;
4738 u32 nxt_offset
= nxt
->timeout
.count
;
4740 if (nxt
->flags
& REQ_F_TIMEOUT_NOSEQ
)
4744 * Since seq + count can overflow, use type long
4747 tmp
= (long long)seq
+ count
;
4748 nxt_seq
= nxt
->sequence
- nxt_offset
;
4749 tmp_nxt
= (long long)nxt_seq
+ nxt_offset
;
4752 * cached_sq_head may overflow, and it will never overflow twice
4753 * once there is some timeout req still be valid.
4762 * Sequence of reqs after the insert one and itself should
4763 * be adjusted because each timeout req consumes a slot.
4768 req
->sequence
-= span
;
4770 list_add(&req
->list
, entry
);
4771 data
->timer
.function
= io_timeout_fn
;
4772 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
4773 spin_unlock_irq(&ctx
->completion_lock
);
4777 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
4779 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
4781 return req
->user_data
== (unsigned long) data
;
4784 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
4786 enum io_wq_cancel cancel_ret
;
4789 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
);
4790 switch (cancel_ret
) {
4791 case IO_WQ_CANCEL_OK
:
4794 case IO_WQ_CANCEL_RUNNING
:
4797 case IO_WQ_CANCEL_NOTFOUND
:
4805 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
4806 struct io_kiocb
*req
, __u64 sqe_addr
,
4809 unsigned long flags
;
4812 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
4813 if (ret
!= -ENOENT
) {
4814 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4818 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4819 ret
= io_timeout_cancel(ctx
, sqe_addr
);
4822 ret
= io_poll_cancel(ctx
, sqe_addr
);
4826 io_cqring_fill_event(req
, ret
);
4827 io_commit_cqring(ctx
);
4828 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
4829 io_cqring_ev_posted(ctx
);
4832 req_set_fail_links(req
);
4836 static int io_async_cancel_prep(struct io_kiocb
*req
,
4837 const struct io_uring_sqe
*sqe
)
4839 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4841 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
||
4845 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
4849 static int io_async_cancel(struct io_kiocb
*req
)
4851 struct io_ring_ctx
*ctx
= req
->ctx
;
4853 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
4857 static int io_files_update_prep(struct io_kiocb
*req
,
4858 const struct io_uring_sqe
*sqe
)
4860 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->rw_flags
)
4863 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
4864 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
4865 if (!req
->files_update
.nr_args
)
4867 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
4871 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
)
4873 struct io_ring_ctx
*ctx
= req
->ctx
;
4874 struct io_uring_files_update up
;
4880 up
.offset
= req
->files_update
.offset
;
4881 up
.fds
= req
->files_update
.arg
;
4883 mutex_lock(&ctx
->uring_lock
);
4884 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
4885 mutex_unlock(&ctx
->uring_lock
);
4888 req_set_fail_links(req
);
4889 io_cqring_add_event(req
, ret
);
4894 static int io_req_defer_prep(struct io_kiocb
*req
,
4895 const struct io_uring_sqe
*sqe
)
4902 if (io_op_defs
[req
->opcode
].file_table
) {
4903 ret
= io_grab_files(req
);
4908 io_req_work_grab_env(req
, &io_op_defs
[req
->opcode
]);
4910 switch (req
->opcode
) {
4913 case IORING_OP_READV
:
4914 case IORING_OP_READ_FIXED
:
4915 case IORING_OP_READ
:
4916 ret
= io_read_prep(req
, sqe
, true);
4918 case IORING_OP_WRITEV
:
4919 case IORING_OP_WRITE_FIXED
:
4920 case IORING_OP_WRITE
:
4921 ret
= io_write_prep(req
, sqe
, true);
4923 case IORING_OP_POLL_ADD
:
4924 ret
= io_poll_add_prep(req
, sqe
);
4926 case IORING_OP_POLL_REMOVE
:
4927 ret
= io_poll_remove_prep(req
, sqe
);
4929 case IORING_OP_FSYNC
:
4930 ret
= io_prep_fsync(req
, sqe
);
4932 case IORING_OP_SYNC_FILE_RANGE
:
4933 ret
= io_prep_sfr(req
, sqe
);
4935 case IORING_OP_SENDMSG
:
4936 case IORING_OP_SEND
:
4937 ret
= io_sendmsg_prep(req
, sqe
);
4939 case IORING_OP_RECVMSG
:
4940 case IORING_OP_RECV
:
4941 ret
= io_recvmsg_prep(req
, sqe
);
4943 case IORING_OP_CONNECT
:
4944 ret
= io_connect_prep(req
, sqe
);
4946 case IORING_OP_TIMEOUT
:
4947 ret
= io_timeout_prep(req
, sqe
, false);
4949 case IORING_OP_TIMEOUT_REMOVE
:
4950 ret
= io_timeout_remove_prep(req
, sqe
);
4952 case IORING_OP_ASYNC_CANCEL
:
4953 ret
= io_async_cancel_prep(req
, sqe
);
4955 case IORING_OP_LINK_TIMEOUT
:
4956 ret
= io_timeout_prep(req
, sqe
, true);
4958 case IORING_OP_ACCEPT
:
4959 ret
= io_accept_prep(req
, sqe
);
4961 case IORING_OP_FALLOCATE
:
4962 ret
= io_fallocate_prep(req
, sqe
);
4964 case IORING_OP_OPENAT
:
4965 ret
= io_openat_prep(req
, sqe
);
4967 case IORING_OP_CLOSE
:
4968 ret
= io_close_prep(req
, sqe
);
4970 case IORING_OP_FILES_UPDATE
:
4971 ret
= io_files_update_prep(req
, sqe
);
4973 case IORING_OP_STATX
:
4974 ret
= io_statx_prep(req
, sqe
);
4976 case IORING_OP_FADVISE
:
4977 ret
= io_fadvise_prep(req
, sqe
);
4979 case IORING_OP_MADVISE
:
4980 ret
= io_madvise_prep(req
, sqe
);
4982 case IORING_OP_OPENAT2
:
4983 ret
= io_openat2_prep(req
, sqe
);
4985 case IORING_OP_EPOLL_CTL
:
4986 ret
= io_epoll_ctl_prep(req
, sqe
);
4988 case IORING_OP_SPLICE
:
4989 ret
= io_splice_prep(req
, sqe
);
4991 case IORING_OP_PROVIDE_BUFFERS
:
4992 ret
= io_provide_buffers_prep(req
, sqe
);
4994 case IORING_OP_REMOVE_BUFFERS
:
4995 ret
= io_remove_buffers_prep(req
, sqe
);
4998 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5007 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5009 struct io_ring_ctx
*ctx
= req
->ctx
;
5012 /* Still need defer if there is pending req in defer list. */
5013 if (!req_need_defer(req
) && list_empty_careful(&ctx
->defer_list
))
5017 if (io_alloc_async_ctx(req
))
5019 ret
= io_req_defer_prep(req
, sqe
);
5024 spin_lock_irq(&ctx
->completion_lock
);
5025 if (!req_need_defer(req
) && list_empty(&ctx
->defer_list
)) {
5026 spin_unlock_irq(&ctx
->completion_lock
);
5030 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5031 list_add_tail(&req
->list
, &ctx
->defer_list
);
5032 spin_unlock_irq(&ctx
->completion_lock
);
5033 return -EIOCBQUEUED
;
5036 static void io_cleanup_req(struct io_kiocb
*req
)
5038 struct io_async_ctx
*io
= req
->io
;
5040 switch (req
->opcode
) {
5041 case IORING_OP_READV
:
5042 case IORING_OP_READ_FIXED
:
5043 case IORING_OP_READ
:
5044 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5045 kfree((void *)(unsigned long)req
->rw
.addr
);
5047 case IORING_OP_WRITEV
:
5048 case IORING_OP_WRITE_FIXED
:
5049 case IORING_OP_WRITE
:
5050 if (io
->rw
.iov
!= io
->rw
.fast_iov
)
5053 case IORING_OP_RECVMSG
:
5054 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5055 kfree(req
->sr_msg
.kbuf
);
5057 case IORING_OP_SENDMSG
:
5058 if (io
->msg
.iov
!= io
->msg
.fast_iov
)
5061 case IORING_OP_RECV
:
5062 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5063 kfree(req
->sr_msg
.kbuf
);
5065 case IORING_OP_OPENAT
:
5066 case IORING_OP_OPENAT2
:
5067 case IORING_OP_STATX
:
5068 putname(req
->open
.filename
);
5070 case IORING_OP_SPLICE
:
5071 io_put_file(req
, req
->splice
.file_in
,
5072 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
5076 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5079 static int io_issue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5080 bool force_nonblock
)
5082 struct io_ring_ctx
*ctx
= req
->ctx
;
5085 switch (req
->opcode
) {
5089 case IORING_OP_READV
:
5090 case IORING_OP_READ_FIXED
:
5091 case IORING_OP_READ
:
5093 ret
= io_read_prep(req
, sqe
, force_nonblock
);
5097 ret
= io_read(req
, force_nonblock
);
5099 case IORING_OP_WRITEV
:
5100 case IORING_OP_WRITE_FIXED
:
5101 case IORING_OP_WRITE
:
5103 ret
= io_write_prep(req
, sqe
, force_nonblock
);
5107 ret
= io_write(req
, force_nonblock
);
5109 case IORING_OP_FSYNC
:
5111 ret
= io_prep_fsync(req
, sqe
);
5115 ret
= io_fsync(req
, force_nonblock
);
5117 case IORING_OP_POLL_ADD
:
5119 ret
= io_poll_add_prep(req
, sqe
);
5123 ret
= io_poll_add(req
);
5125 case IORING_OP_POLL_REMOVE
:
5127 ret
= io_poll_remove_prep(req
, sqe
);
5131 ret
= io_poll_remove(req
);
5133 case IORING_OP_SYNC_FILE_RANGE
:
5135 ret
= io_prep_sfr(req
, sqe
);
5139 ret
= io_sync_file_range(req
, force_nonblock
);
5141 case IORING_OP_SENDMSG
:
5142 case IORING_OP_SEND
:
5144 ret
= io_sendmsg_prep(req
, sqe
);
5148 if (req
->opcode
== IORING_OP_SENDMSG
)
5149 ret
= io_sendmsg(req
, force_nonblock
);
5151 ret
= io_send(req
, force_nonblock
);
5153 case IORING_OP_RECVMSG
:
5154 case IORING_OP_RECV
:
5156 ret
= io_recvmsg_prep(req
, sqe
);
5160 if (req
->opcode
== IORING_OP_RECVMSG
)
5161 ret
= io_recvmsg(req
, force_nonblock
);
5163 ret
= io_recv(req
, force_nonblock
);
5165 case IORING_OP_TIMEOUT
:
5167 ret
= io_timeout_prep(req
, sqe
, false);
5171 ret
= io_timeout(req
);
5173 case IORING_OP_TIMEOUT_REMOVE
:
5175 ret
= io_timeout_remove_prep(req
, sqe
);
5179 ret
= io_timeout_remove(req
);
5181 case IORING_OP_ACCEPT
:
5183 ret
= io_accept_prep(req
, sqe
);
5187 ret
= io_accept(req
, force_nonblock
);
5189 case IORING_OP_CONNECT
:
5191 ret
= io_connect_prep(req
, sqe
);
5195 ret
= io_connect(req
, force_nonblock
);
5197 case IORING_OP_ASYNC_CANCEL
:
5199 ret
= io_async_cancel_prep(req
, sqe
);
5203 ret
= io_async_cancel(req
);
5205 case IORING_OP_FALLOCATE
:
5207 ret
= io_fallocate_prep(req
, sqe
);
5211 ret
= io_fallocate(req
, force_nonblock
);
5213 case IORING_OP_OPENAT
:
5215 ret
= io_openat_prep(req
, sqe
);
5219 ret
= io_openat(req
, force_nonblock
);
5221 case IORING_OP_CLOSE
:
5223 ret
= io_close_prep(req
, sqe
);
5227 ret
= io_close(req
, force_nonblock
);
5229 case IORING_OP_FILES_UPDATE
:
5231 ret
= io_files_update_prep(req
, sqe
);
5235 ret
= io_files_update(req
, force_nonblock
);
5237 case IORING_OP_STATX
:
5239 ret
= io_statx_prep(req
, sqe
);
5243 ret
= io_statx(req
, force_nonblock
);
5245 case IORING_OP_FADVISE
:
5247 ret
= io_fadvise_prep(req
, sqe
);
5251 ret
= io_fadvise(req
, force_nonblock
);
5253 case IORING_OP_MADVISE
:
5255 ret
= io_madvise_prep(req
, sqe
);
5259 ret
= io_madvise(req
, force_nonblock
);
5261 case IORING_OP_OPENAT2
:
5263 ret
= io_openat2_prep(req
, sqe
);
5267 ret
= io_openat2(req
, force_nonblock
);
5269 case IORING_OP_EPOLL_CTL
:
5271 ret
= io_epoll_ctl_prep(req
, sqe
);
5275 ret
= io_epoll_ctl(req
, force_nonblock
);
5277 case IORING_OP_SPLICE
:
5279 ret
= io_splice_prep(req
, sqe
);
5283 ret
= io_splice(req
, force_nonblock
);
5285 case IORING_OP_PROVIDE_BUFFERS
:
5287 ret
= io_provide_buffers_prep(req
, sqe
);
5291 ret
= io_provide_buffers(req
, force_nonblock
);
5293 case IORING_OP_REMOVE_BUFFERS
:
5295 ret
= io_remove_buffers_prep(req
, sqe
);
5299 ret
= io_remove_buffers(req
, force_nonblock
);
5309 /* If the op doesn't have a file, we're not polling for it */
5310 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
5311 const bool in_async
= io_wq_current_is_worker();
5313 if (req
->result
== -EAGAIN
)
5316 /* workqueue context doesn't hold uring_lock, grab it now */
5318 mutex_lock(&ctx
->uring_lock
);
5320 io_iopoll_req_issued(req
);
5323 mutex_unlock(&ctx
->uring_lock
);
5329 static void io_wq_submit_work(struct io_wq_work
**workptr
)
5331 struct io_wq_work
*work
= *workptr
;
5332 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5335 /* if NO_CANCEL is set, we must still run the work */
5336 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
5337 IO_WQ_WORK_CANCEL
) {
5343 ret
= io_issue_sqe(req
, NULL
, false);
5345 * We can get EAGAIN for polled IO even though we're
5346 * forcing a sync submission from here, since we can't
5347 * wait for request slots on the block side.
5356 req_set_fail_links(req
);
5357 io_cqring_add_event(req
, ret
);
5361 io_steal_work(req
, workptr
);
5364 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
5367 struct fixed_file_table
*table
;
5369 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
5370 return table
->files
[index
& IORING_FILE_TABLE_MASK
];;
5373 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
5374 int fd
, struct file
**out_file
, bool fixed
)
5376 struct io_ring_ctx
*ctx
= req
->ctx
;
5380 if (unlikely(!ctx
->file_data
||
5381 (unsigned) fd
>= ctx
->nr_user_files
))
5383 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
5384 file
= io_file_from_index(ctx
, fd
);
5387 req
->fixed_file_refs
= ctx
->file_data
->cur_refs
;
5388 percpu_ref_get(req
->fixed_file_refs
);
5390 trace_io_uring_file_get(ctx
, fd
);
5391 file
= __io_file_get(state
, fd
);
5392 if (unlikely(!file
))
5400 static int io_req_set_file(struct io_submit_state
*state
, struct io_kiocb
*req
,
5405 fixed
= (req
->flags
& REQ_F_FIXED_FILE
) != 0;
5406 if (unlikely(!fixed
&& req
->needs_fixed_file
))
5409 return io_file_get(state
, req
, fd
, &req
->file
, fixed
);
5412 static int io_grab_files(struct io_kiocb
*req
)
5415 struct io_ring_ctx
*ctx
= req
->ctx
;
5417 if (req
->work
.files
|| (req
->flags
& REQ_F_NO_FILE_TABLE
))
5419 if (!ctx
->ring_file
)
5423 spin_lock_irq(&ctx
->inflight_lock
);
5425 * We use the f_ops->flush() handler to ensure that we can flush
5426 * out work accessing these files if the fd is closed. Check if
5427 * the fd has changed since we started down this path, and disallow
5428 * this operation if it has.
5430 if (fcheck(ctx
->ring_fd
) == ctx
->ring_file
) {
5431 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
5432 req
->flags
|= REQ_F_INFLIGHT
;
5433 req
->work
.files
= current
->files
;
5436 spin_unlock_irq(&ctx
->inflight_lock
);
5442 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
5444 struct io_timeout_data
*data
= container_of(timer
,
5445 struct io_timeout_data
, timer
);
5446 struct io_kiocb
*req
= data
->req
;
5447 struct io_ring_ctx
*ctx
= req
->ctx
;
5448 struct io_kiocb
*prev
= NULL
;
5449 unsigned long flags
;
5451 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5454 * We don't expect the list to be empty, that will only happen if we
5455 * race with the completion of the linked work.
5457 if (!list_empty(&req
->link_list
)) {
5458 prev
= list_entry(req
->link_list
.prev
, struct io_kiocb
,
5460 if (refcount_inc_not_zero(&prev
->refs
)) {
5461 list_del_init(&req
->link_list
);
5462 prev
->flags
&= ~REQ_F_LINK_TIMEOUT
;
5467 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5470 req_set_fail_links(prev
);
5471 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
5474 io_cqring_add_event(req
, -ETIME
);
5477 return HRTIMER_NORESTART
;
5480 static void io_queue_linked_timeout(struct io_kiocb
*req
)
5482 struct io_ring_ctx
*ctx
= req
->ctx
;
5485 * If the list is now empty, then our linked request finished before
5486 * we got a chance to setup the timer
5488 spin_lock_irq(&ctx
->completion_lock
);
5489 if (!list_empty(&req
->link_list
)) {
5490 struct io_timeout_data
*data
= &req
->io
->timeout
;
5492 data
->timer
.function
= io_link_timeout_fn
;
5493 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
5496 spin_unlock_irq(&ctx
->completion_lock
);
5498 /* drop submission reference */
5502 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
5504 struct io_kiocb
*nxt
;
5506 if (!(req
->flags
& REQ_F_LINK_HEAD
))
5508 /* for polled retry, if flag is set, we already went through here */
5509 if (req
->flags
& REQ_F_POLLED
)
5512 nxt
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
5514 if (!nxt
|| nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
5517 req
->flags
|= REQ_F_LINK_TIMEOUT
;
5521 static void __io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5523 struct io_kiocb
*linked_timeout
;
5524 struct io_kiocb
*nxt
;
5525 const struct cred
*old_creds
= NULL
;
5529 linked_timeout
= io_prep_linked_timeout(req
);
5531 if (req
->work
.creds
&& req
->work
.creds
!= current_cred()) {
5533 revert_creds(old_creds
);
5534 if (old_creds
== req
->work
.creds
)
5535 old_creds
= NULL
; /* restored original creds */
5537 old_creds
= override_creds(req
->work
.creds
);
5540 ret
= io_issue_sqe(req
, sqe
, true);
5543 * We async punt it if the file wasn't marked NOWAIT, or if the file
5544 * doesn't support non-blocking read/write attempts
5546 if (ret
== -EAGAIN
&& (!(req
->flags
& REQ_F_NOWAIT
) ||
5547 (req
->flags
& REQ_F_MUST_PUNT
))) {
5548 if (io_arm_poll_handler(req
)) {
5550 io_queue_linked_timeout(linked_timeout
);
5554 if (io_op_defs
[req
->opcode
].file_table
) {
5555 ret
= io_grab_files(req
);
5561 * Queued up for async execution, worker will release
5562 * submit reference when the iocb is actually submitted.
5564 io_queue_async_work(req
);
5570 /* drop submission reference */
5571 io_put_req_find_next(req
, &nxt
);
5573 if (linked_timeout
) {
5575 io_queue_linked_timeout(linked_timeout
);
5577 io_put_req(linked_timeout
);
5580 /* and drop final reference, if we failed */
5582 io_cqring_add_event(req
, ret
);
5583 req_set_fail_links(req
);
5589 if (req
->flags
& REQ_F_FORCE_ASYNC
)
5595 revert_creds(old_creds
);
5598 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5602 ret
= io_req_defer(req
, sqe
);
5604 if (ret
!= -EIOCBQUEUED
) {
5606 io_cqring_add_event(req
, ret
);
5607 req_set_fail_links(req
);
5608 io_double_put_req(req
);
5610 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
5613 if (io_alloc_async_ctx(req
))
5615 ret
= io_req_defer_prep(req
, sqe
);
5616 if (unlikely(ret
< 0))
5621 * Never try inline submit of IOSQE_ASYNC is set, go straight
5622 * to async execution.
5624 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
5625 io_queue_async_work(req
);
5627 __io_queue_sqe(req
, sqe
);
5631 static inline void io_queue_link_head(struct io_kiocb
*req
)
5633 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
5634 io_cqring_add_event(req
, -ECANCELED
);
5635 io_double_put_req(req
);
5637 io_queue_sqe(req
, NULL
);
5640 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5641 struct io_submit_state
*state
, struct io_kiocb
**link
)
5643 struct io_ring_ctx
*ctx
= req
->ctx
;
5647 * If we already have a head request, queue this one for async
5648 * submittal once the head completes. If we don't have a head but
5649 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
5650 * submitted sync once the chain is complete. If none of those
5651 * conditions are true (normal request), then just queue it.
5654 struct io_kiocb
*head
= *link
;
5657 * Taking sequential execution of a link, draining both sides
5658 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
5659 * requests in the link. So, it drains the head and the
5660 * next after the link request. The last one is done via
5661 * drain_next flag to persist the effect across calls.
5663 if (req
->flags
& REQ_F_IO_DRAIN
) {
5664 head
->flags
|= REQ_F_IO_DRAIN
;
5665 ctx
->drain_next
= 1;
5667 if (io_alloc_async_ctx(req
))
5670 ret
= io_req_defer_prep(req
, sqe
);
5672 /* fail even hard links since we don't submit */
5673 head
->flags
|= REQ_F_FAIL_LINK
;
5676 trace_io_uring_link(ctx
, req
, head
);
5677 list_add_tail(&req
->link_list
, &head
->link_list
);
5679 /* last request of a link, enqueue the link */
5680 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
5681 io_queue_link_head(head
);
5685 if (unlikely(ctx
->drain_next
)) {
5686 req
->flags
|= REQ_F_IO_DRAIN
;
5687 ctx
->drain_next
= 0;
5689 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
5690 req
->flags
|= REQ_F_LINK_HEAD
;
5691 INIT_LIST_HEAD(&req
->link_list
);
5693 if (io_alloc_async_ctx(req
))
5696 ret
= io_req_defer_prep(req
, sqe
);
5698 req
->flags
|= REQ_F_FAIL_LINK
;
5701 io_queue_sqe(req
, sqe
);
5709 * Batched submission is done, ensure local IO is flushed out.
5711 static void io_submit_state_end(struct io_submit_state
*state
)
5713 blk_finish_plug(&state
->plug
);
5715 if (state
->free_reqs
)
5716 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
5720 * Start submission side cache.
5722 static void io_submit_state_start(struct io_submit_state
*state
,
5723 unsigned int max_ios
)
5725 blk_start_plug(&state
->plug
);
5726 state
->free_reqs
= 0;
5728 state
->ios_left
= max_ios
;
5731 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
5733 struct io_rings
*rings
= ctx
->rings
;
5736 * Ensure any loads from the SQEs are done at this point,
5737 * since once we write the new head, the application could
5738 * write new data to them.
5740 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
5744 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
5745 * that is mapped by userspace. This means that care needs to be taken to
5746 * ensure that reads are stable, as we cannot rely on userspace always
5747 * being a good citizen. If members of the sqe are validated and then later
5748 * used, it's important that those reads are done through READ_ONCE() to
5749 * prevent a re-load down the line.
5751 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
5753 u32
*sq_array
= ctx
->sq_array
;
5757 * The cached sq head (or cq tail) serves two purposes:
5759 * 1) allows us to batch the cost of updating the user visible
5761 * 2) allows the kernel side to track the head on its own, even
5762 * though the application is the one updating it.
5764 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
5765 if (likely(head
< ctx
->sq_entries
))
5766 return &ctx
->sq_sqes
[head
];
5768 /* drop invalid entries */
5769 ctx
->cached_sq_dropped
++;
5770 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
5774 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
5776 ctx
->cached_sq_head
++;
5779 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
5780 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
5781 IOSQE_BUFFER_SELECT)
5783 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
5784 const struct io_uring_sqe
*sqe
,
5785 struct io_submit_state
*state
, bool async
)
5787 unsigned int sqe_flags
;
5791 * All io need record the previous position, if LINK vs DARIN,
5792 * it can be used to mark the position of the first IO in the
5795 req
->sequence
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5796 req
->opcode
= READ_ONCE(sqe
->opcode
);
5797 req
->user_data
= READ_ONCE(sqe
->user_data
);
5802 /* one is dropped after submission, the other at completion */
5803 refcount_set(&req
->refs
, 2);
5806 req
->needs_fixed_file
= async
;
5807 INIT_IO_WORK(&req
->work
, io_wq_submit_work
);
5809 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
5812 if (io_op_defs
[req
->opcode
].needs_mm
&& !current
->mm
) {
5813 if (unlikely(!mmget_not_zero(ctx
->sqo_mm
)))
5815 use_mm(ctx
->sqo_mm
);
5818 sqe_flags
= READ_ONCE(sqe
->flags
);
5819 /* enforce forwards compatibility on users */
5820 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
5823 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
5824 !io_op_defs
[req
->opcode
].buffer_select
)
5827 id
= READ_ONCE(sqe
->personality
);
5829 req
->work
.creds
= idr_find(&ctx
->personality_idr
, id
);
5830 if (unlikely(!req
->work
.creds
))
5832 get_cred(req
->work
.creds
);
5835 /* same numerical values with corresponding REQ_F_*, safe to copy */
5836 req
->flags
|= sqe_flags
& (IOSQE_IO_DRAIN
| IOSQE_IO_HARDLINK
|
5837 IOSQE_ASYNC
| IOSQE_FIXED_FILE
|
5838 IOSQE_BUFFER_SELECT
| IOSQE_IO_LINK
);
5840 if (!io_op_defs
[req
->opcode
].needs_file
)
5843 return io_req_set_file(state
, req
, READ_ONCE(sqe
->fd
));
5846 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
,
5847 struct file
*ring_file
, int ring_fd
, bool async
)
5849 struct io_submit_state state
, *statep
= NULL
;
5850 struct io_kiocb
*link
= NULL
;
5851 int i
, submitted
= 0;
5853 /* if we have a backlog and couldn't flush it all, return BUSY */
5854 if (test_bit(0, &ctx
->sq_check_overflow
)) {
5855 if (!list_empty(&ctx
->cq_overflow_list
) &&
5856 !io_cqring_overflow_flush(ctx
, false))
5860 /* make sure SQ entry isn't read before tail */
5861 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
5863 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
5866 if (nr
> IO_PLUG_THRESHOLD
) {
5867 io_submit_state_start(&state
, nr
);
5871 ctx
->ring_fd
= ring_fd
;
5872 ctx
->ring_file
= ring_file
;
5874 for (i
= 0; i
< nr
; i
++) {
5875 const struct io_uring_sqe
*sqe
;
5876 struct io_kiocb
*req
;
5879 sqe
= io_get_sqe(ctx
);
5880 if (unlikely(!sqe
)) {
5881 io_consume_sqe(ctx
);
5884 req
= io_alloc_req(ctx
, statep
);
5885 if (unlikely(!req
)) {
5887 submitted
= -EAGAIN
;
5891 err
= io_init_req(ctx
, req
, sqe
, statep
, async
);
5892 io_consume_sqe(ctx
);
5893 /* will complete beyond this point, count as submitted */
5896 if (unlikely(err
)) {
5898 io_cqring_add_event(req
, err
);
5899 io_double_put_req(req
);
5903 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
5905 err
= io_submit_sqe(req
, sqe
, statep
, &link
);
5910 if (unlikely(submitted
!= nr
)) {
5911 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
5913 percpu_ref_put_many(&ctx
->refs
, nr
- ref_used
);
5916 io_queue_link_head(link
);
5918 io_submit_state_end(&state
);
5920 /* Commit SQ ring head once we've consumed and submitted all SQEs */
5921 io_commit_sqring(ctx
);
5926 static inline void io_sq_thread_drop_mm(struct io_ring_ctx
*ctx
)
5928 struct mm_struct
*mm
= current
->mm
;
5936 static int io_sq_thread(void *data
)
5938 struct io_ring_ctx
*ctx
= data
;
5939 const struct cred
*old_cred
;
5940 mm_segment_t old_fs
;
5942 unsigned long timeout
;
5945 complete(&ctx
->completions
[1]);
5949 old_cred
= override_creds(ctx
->creds
);
5951 timeout
= jiffies
+ ctx
->sq_thread_idle
;
5952 while (!kthread_should_park()) {
5953 unsigned int to_submit
;
5955 if (!list_empty(&ctx
->poll_list
)) {
5956 unsigned nr_events
= 0;
5958 mutex_lock(&ctx
->uring_lock
);
5959 if (!list_empty(&ctx
->poll_list
))
5960 io_iopoll_getevents(ctx
, &nr_events
, 0);
5962 timeout
= jiffies
+ ctx
->sq_thread_idle
;
5963 mutex_unlock(&ctx
->uring_lock
);
5966 to_submit
= io_sqring_entries(ctx
);
5969 * If submit got -EBUSY, flag us as needing the application
5970 * to enter the kernel to reap and flush events.
5972 if (!to_submit
|| ret
== -EBUSY
) {
5974 * Drop cur_mm before scheduling, we can't hold it for
5975 * long periods (or over schedule()). Do this before
5976 * adding ourselves to the waitqueue, as the unuse/drop
5979 io_sq_thread_drop_mm(ctx
);
5982 * We're polling. If we're within the defined idle
5983 * period, then let us spin without work before going
5984 * to sleep. The exception is if we got EBUSY doing
5985 * more IO, we should wait for the application to
5986 * reap events and wake us up.
5988 if (!list_empty(&ctx
->poll_list
) ||
5989 (!time_after(jiffies
, timeout
) && ret
!= -EBUSY
&&
5990 !percpu_ref_is_dying(&ctx
->refs
))) {
5991 if (current
->task_works
)
5997 prepare_to_wait(&ctx
->sqo_wait
, &wait
,
5998 TASK_INTERRUPTIBLE
);
6001 * While doing polled IO, before going to sleep, we need
6002 * to check if there are new reqs added to poll_list, it
6003 * is because reqs may have been punted to io worker and
6004 * will be added to poll_list later, hence check the
6007 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6008 !list_empty_careful(&ctx
->poll_list
)) {
6009 finish_wait(&ctx
->sqo_wait
, &wait
);
6013 /* Tell userspace we may need a wakeup call */
6014 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6015 /* make sure to read SQ tail after writing flags */
6018 to_submit
= io_sqring_entries(ctx
);
6019 if (!to_submit
|| ret
== -EBUSY
) {
6020 if (kthread_should_park()) {
6021 finish_wait(&ctx
->sqo_wait
, &wait
);
6024 if (current
->task_works
) {
6026 finish_wait(&ctx
->sqo_wait
, &wait
);
6029 if (signal_pending(current
))
6030 flush_signals(current
);
6032 finish_wait(&ctx
->sqo_wait
, &wait
);
6034 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6038 finish_wait(&ctx
->sqo_wait
, &wait
);
6040 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6043 mutex_lock(&ctx
->uring_lock
);
6044 ret
= io_submit_sqes(ctx
, to_submit
, NULL
, -1, true);
6045 mutex_unlock(&ctx
->uring_lock
);
6046 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6049 if (current
->task_works
)
6053 io_sq_thread_drop_mm(ctx
);
6054 revert_creds(old_cred
);
6061 struct io_wait_queue
{
6062 struct wait_queue_entry wq
;
6063 struct io_ring_ctx
*ctx
;
6065 unsigned nr_timeouts
;
6068 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
6070 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6073 * Wake up if we have enough events, or if a timeout occurred since we
6074 * started waiting. For timeouts, we always want to return to userspace,
6075 * regardless of event count.
6077 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
6078 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6081 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6082 int wake_flags
, void *key
)
6084 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6087 /* use noflush == true, as we can't safely rely on locking context */
6088 if (!io_should_wake(iowq
, true))
6091 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6095 * Wait until events become available, if we don't already have some. The
6096 * application must reap them itself, as they reside on the shared cq ring.
6098 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6099 const sigset_t __user
*sig
, size_t sigsz
)
6101 struct io_wait_queue iowq
= {
6104 .func
= io_wake_function
,
6105 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6108 .to_wait
= min_events
,
6110 struct io_rings
*rings
= ctx
->rings
;
6114 if (io_cqring_events(ctx
, false) >= min_events
)
6116 if (!current
->task_works
)
6122 #ifdef CONFIG_COMPAT
6123 if (in_compat_syscall())
6124 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6128 ret
= set_user_sigmask(sig
, sigsz
);
6134 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6135 trace_io_uring_cqring_wait(ctx
, min_events
);
6137 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
6138 TASK_INTERRUPTIBLE
);
6139 if (current
->task_works
)
6141 if (io_should_wake(&iowq
, false))
6144 if (signal_pending(current
)) {
6149 finish_wait(&ctx
->wait
, &iowq
.wq
);
6151 restore_saved_sigmask_unless(ret
== -EINTR
);
6153 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
6156 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6158 #if defined(CONFIG_UNIX)
6159 if (ctx
->ring_sock
) {
6160 struct sock
*sock
= ctx
->ring_sock
->sk
;
6161 struct sk_buff
*skb
;
6163 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
6169 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6172 file
= io_file_from_index(ctx
, i
);
6179 static void io_file_ref_kill(struct percpu_ref
*ref
)
6181 struct fixed_file_data
*data
;
6183 data
= container_of(ref
, struct fixed_file_data
, refs
);
6184 complete(&data
->done
);
6187 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6189 struct fixed_file_data
*data
= ctx
->file_data
;
6190 struct fixed_file_ref_node
*ref_node
= NULL
;
6191 unsigned nr_tables
, i
;
6192 unsigned long flags
;
6197 spin_lock_irqsave(&data
->lock
, flags
);
6198 if (!list_empty(&data
->ref_list
))
6199 ref_node
= list_first_entry(&data
->ref_list
,
6200 struct fixed_file_ref_node
, node
);
6201 spin_unlock_irqrestore(&data
->lock
, flags
);
6203 percpu_ref_kill(&ref_node
->refs
);
6205 percpu_ref_kill(&data
->refs
);
6207 /* wait for all refs nodes to complete */
6208 wait_for_completion(&data
->done
);
6210 __io_sqe_files_unregister(ctx
);
6211 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
6212 for (i
= 0; i
< nr_tables
; i
++)
6213 kfree(data
->table
[i
].files
);
6215 percpu_ref_exit(&data
->refs
);
6217 ctx
->file_data
= NULL
;
6218 ctx
->nr_user_files
= 0;
6222 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
6224 if (ctx
->sqo_thread
) {
6225 wait_for_completion(&ctx
->completions
[1]);
6227 * The park is a bit of a work-around, without it we get
6228 * warning spews on shutdown with SQPOLL set and affinity
6229 * set to a single CPU.
6231 kthread_park(ctx
->sqo_thread
);
6232 kthread_stop(ctx
->sqo_thread
);
6233 ctx
->sqo_thread
= NULL
;
6237 static void io_finish_async(struct io_ring_ctx
*ctx
)
6239 io_sq_thread_stop(ctx
);
6242 io_wq_destroy(ctx
->io_wq
);
6247 #if defined(CONFIG_UNIX)
6249 * Ensure the UNIX gc is aware of our file set, so we are certain that
6250 * the io_uring can be safely unregistered on process exit, even if we have
6251 * loops in the file referencing.
6253 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
6255 struct sock
*sk
= ctx
->ring_sock
->sk
;
6256 struct scm_fp_list
*fpl
;
6257 struct sk_buff
*skb
;
6260 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
6264 skb
= alloc_skb(0, GFP_KERNEL
);
6273 fpl
->user
= get_uid(ctx
->user
);
6274 for (i
= 0; i
< nr
; i
++) {
6275 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
6279 fpl
->fp
[nr_files
] = get_file(file
);
6280 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
6285 fpl
->max
= SCM_MAX_FD
;
6286 fpl
->count
= nr_files
;
6287 UNIXCB(skb
).fp
= fpl
;
6288 skb
->destructor
= unix_destruct_scm
;
6289 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
6290 skb_queue_head(&sk
->sk_receive_queue
, skb
);
6292 for (i
= 0; i
< nr_files
; i
++)
6303 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
6304 * causes regular reference counting to break down. We rely on the UNIX
6305 * garbage collection to take care of this problem for us.
6307 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6309 unsigned left
, total
;
6313 left
= ctx
->nr_user_files
;
6315 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
6317 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
6321 total
+= this_files
;
6327 while (total
< ctx
->nr_user_files
) {
6328 struct file
*file
= io_file_from_index(ctx
, total
);
6338 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6344 static int io_sqe_alloc_file_tables(struct io_ring_ctx
*ctx
, unsigned nr_tables
,
6349 for (i
= 0; i
< nr_tables
; i
++) {
6350 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6351 unsigned this_files
;
6353 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
6354 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
6358 nr_files
-= this_files
;
6364 for (i
= 0; i
< nr_tables
; i
++) {
6365 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6366 kfree(table
->files
);
6371 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
6373 #if defined(CONFIG_UNIX)
6374 struct sock
*sock
= ctx
->ring_sock
->sk
;
6375 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
6376 struct sk_buff
*skb
;
6379 __skb_queue_head_init(&list
);
6382 * Find the skb that holds this file in its SCM_RIGHTS. When found,
6383 * remove this entry and rearrange the file array.
6385 skb
= skb_dequeue(head
);
6387 struct scm_fp_list
*fp
;
6389 fp
= UNIXCB(skb
).fp
;
6390 for (i
= 0; i
< fp
->count
; i
++) {
6393 if (fp
->fp
[i
] != file
)
6396 unix_notinflight(fp
->user
, fp
->fp
[i
]);
6397 left
= fp
->count
- 1 - i
;
6399 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
6400 left
* sizeof(struct file
*));
6407 __skb_queue_tail(&list
, skb
);
6417 __skb_queue_tail(&list
, skb
);
6419 skb
= skb_dequeue(head
);
6422 if (skb_peek(&list
)) {
6423 spin_lock_irq(&head
->lock
);
6424 while ((skb
= __skb_dequeue(&list
)) != NULL
)
6425 __skb_queue_tail(head
, skb
);
6426 spin_unlock_irq(&head
->lock
);
6433 struct io_file_put
{
6434 struct list_head list
;
6438 static void io_file_put_work(struct work_struct
*work
)
6440 struct fixed_file_ref_node
*ref_node
;
6441 struct fixed_file_data
*file_data
;
6442 struct io_ring_ctx
*ctx
;
6443 struct io_file_put
*pfile
, *tmp
;
6444 unsigned long flags
;
6446 ref_node
= container_of(work
, struct fixed_file_ref_node
, work
);
6447 file_data
= ref_node
->file_data
;
6448 ctx
= file_data
->ctx
;
6450 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
6451 list_del_init(&pfile
->list
);
6452 io_ring_file_put(ctx
, pfile
->file
);
6456 spin_lock_irqsave(&file_data
->lock
, flags
);
6457 list_del_init(&ref_node
->node
);
6458 spin_unlock_irqrestore(&file_data
->lock
, flags
);
6460 percpu_ref_exit(&ref_node
->refs
);
6462 percpu_ref_put(&file_data
->refs
);
6465 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
6467 struct fixed_file_ref_node
*ref_node
;
6469 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
6471 queue_work(system_wq
, &ref_node
->work
);
6474 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
6475 struct io_ring_ctx
*ctx
)
6477 struct fixed_file_ref_node
*ref_node
;
6479 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
6481 return ERR_PTR(-ENOMEM
);
6483 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
6486 return ERR_PTR(-ENOMEM
);
6488 INIT_LIST_HEAD(&ref_node
->node
);
6489 INIT_LIST_HEAD(&ref_node
->file_list
);
6490 INIT_WORK(&ref_node
->work
, io_file_put_work
);
6491 ref_node
->file_data
= ctx
->file_data
;
6496 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
6498 percpu_ref_exit(&ref_node
->refs
);
6502 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
6505 __s32 __user
*fds
= (__s32 __user
*) arg
;
6510 struct fixed_file_ref_node
*ref_node
;
6511 unsigned long flags
;
6517 if (nr_args
> IORING_MAX_FIXED_FILES
)
6520 ctx
->file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
6521 if (!ctx
->file_data
)
6523 ctx
->file_data
->ctx
= ctx
;
6524 init_completion(&ctx
->file_data
->done
);
6525 INIT_LIST_HEAD(&ctx
->file_data
->ref_list
);
6526 spin_lock_init(&ctx
->file_data
->lock
);
6528 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
6529 ctx
->file_data
->table
= kcalloc(nr_tables
,
6530 sizeof(struct fixed_file_table
),
6532 if (!ctx
->file_data
->table
) {
6533 kfree(ctx
->file_data
);
6534 ctx
->file_data
= NULL
;
6538 if (percpu_ref_init(&ctx
->file_data
->refs
, io_file_ref_kill
,
6539 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
)) {
6540 kfree(ctx
->file_data
->table
);
6541 kfree(ctx
->file_data
);
6542 ctx
->file_data
= NULL
;
6546 if (io_sqe_alloc_file_tables(ctx
, nr_tables
, nr_args
)) {
6547 percpu_ref_exit(&ctx
->file_data
->refs
);
6548 kfree(ctx
->file_data
->table
);
6549 kfree(ctx
->file_data
);
6550 ctx
->file_data
= NULL
;
6554 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
6555 struct fixed_file_table
*table
;
6559 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
)))
6561 /* allow sparse sets */
6567 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
6568 index
= i
& IORING_FILE_TABLE_MASK
;
6576 * Don't allow io_uring instances to be registered. If UNIX
6577 * isn't enabled, then this causes a reference cycle and this
6578 * instance can never get freed. If UNIX is enabled we'll
6579 * handle it just fine, but there's still no point in allowing
6580 * a ring fd as it doesn't support regular read/write anyway.
6582 if (file
->f_op
== &io_uring_fops
) {
6587 table
->files
[index
] = file
;
6591 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6592 file
= io_file_from_index(ctx
, i
);
6596 for (i
= 0; i
< nr_tables
; i
++)
6597 kfree(ctx
->file_data
->table
[i
].files
);
6599 kfree(ctx
->file_data
->table
);
6600 kfree(ctx
->file_data
);
6601 ctx
->file_data
= NULL
;
6602 ctx
->nr_user_files
= 0;
6606 ret
= io_sqe_files_scm(ctx
);
6608 io_sqe_files_unregister(ctx
);
6612 ref_node
= alloc_fixed_file_ref_node(ctx
);
6613 if (IS_ERR(ref_node
)) {
6614 io_sqe_files_unregister(ctx
);
6615 return PTR_ERR(ref_node
);
6618 ctx
->file_data
->cur_refs
= &ref_node
->refs
;
6619 spin_lock_irqsave(&ctx
->file_data
->lock
, flags
);
6620 list_add(&ref_node
->node
, &ctx
->file_data
->ref_list
);
6621 spin_unlock_irqrestore(&ctx
->file_data
->lock
, flags
);
6622 percpu_ref_get(&ctx
->file_data
->refs
);
6626 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
6629 #if defined(CONFIG_UNIX)
6630 struct sock
*sock
= ctx
->ring_sock
->sk
;
6631 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
6632 struct sk_buff
*skb
;
6635 * See if we can merge this file into an existing skb SCM_RIGHTS
6636 * file set. If there's no room, fall back to allocating a new skb
6637 * and filling it in.
6639 spin_lock_irq(&head
->lock
);
6640 skb
= skb_peek(head
);
6642 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
6644 if (fpl
->count
< SCM_MAX_FD
) {
6645 __skb_unlink(skb
, head
);
6646 spin_unlock_irq(&head
->lock
);
6647 fpl
->fp
[fpl
->count
] = get_file(file
);
6648 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
6650 spin_lock_irq(&head
->lock
);
6651 __skb_queue_head(head
, skb
);
6656 spin_unlock_irq(&head
->lock
);
6663 return __io_sqe_files_scm(ctx
, 1, index
);
6669 static int io_queue_file_removal(struct fixed_file_data
*data
,
6672 struct io_file_put
*pfile
;
6673 struct percpu_ref
*refs
= data
->cur_refs
;
6674 struct fixed_file_ref_node
*ref_node
;
6676 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
6680 ref_node
= container_of(refs
, struct fixed_file_ref_node
, refs
);
6682 list_add(&pfile
->list
, &ref_node
->file_list
);
6687 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
6688 struct io_uring_files_update
*up
,
6691 struct fixed_file_data
*data
= ctx
->file_data
;
6692 struct fixed_file_ref_node
*ref_node
;
6697 unsigned long flags
;
6698 bool needs_switch
= false;
6700 if (check_add_overflow(up
->offset
, nr_args
, &done
))
6702 if (done
> ctx
->nr_user_files
)
6705 ref_node
= alloc_fixed_file_ref_node(ctx
);
6706 if (IS_ERR(ref_node
))
6707 return PTR_ERR(ref_node
);
6710 fds
= u64_to_user_ptr(up
->fds
);
6712 struct fixed_file_table
*table
;
6716 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
6720 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
6721 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
6722 index
= i
& IORING_FILE_TABLE_MASK
;
6723 if (table
->files
[index
]) {
6724 file
= io_file_from_index(ctx
, index
);
6725 err
= io_queue_file_removal(data
, file
);
6728 table
->files
[index
] = NULL
;
6729 needs_switch
= true;
6738 * Don't allow io_uring instances to be registered. If
6739 * UNIX isn't enabled, then this causes a reference
6740 * cycle and this instance can never get freed. If UNIX
6741 * is enabled we'll handle it just fine, but there's
6742 * still no point in allowing a ring fd as it doesn't
6743 * support regular read/write anyway.
6745 if (file
->f_op
== &io_uring_fops
) {
6750 table
->files
[index
] = file
;
6751 err
= io_sqe_file_register(ctx
, file
, i
);
6761 percpu_ref_kill(data
->cur_refs
);
6762 spin_lock_irqsave(&data
->lock
, flags
);
6763 list_add(&ref_node
->node
, &data
->ref_list
);
6764 data
->cur_refs
= &ref_node
->refs
;
6765 spin_unlock_irqrestore(&data
->lock
, flags
);
6766 percpu_ref_get(&ctx
->file_data
->refs
);
6768 destroy_fixed_file_ref_node(ref_node
);
6770 return done
? done
: err
;
6773 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
6776 struct io_uring_files_update up
;
6778 if (!ctx
->file_data
)
6782 if (copy_from_user(&up
, arg
, sizeof(up
)))
6787 return __io_sqe_files_update(ctx
, &up
, nr_args
);
6790 static void io_free_work(struct io_wq_work
*work
)
6792 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6794 /* Consider that io_steal_work() relies on this ref */
6798 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
6799 struct io_uring_params
*p
)
6801 struct io_wq_data data
;
6803 struct io_ring_ctx
*ctx_attach
;
6804 unsigned int concurrency
;
6807 data
.user
= ctx
->user
;
6808 data
.free_work
= io_free_work
;
6810 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
6811 /* Do QD, or 4 * CPUS, whatever is smallest */
6812 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
6814 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
6815 if (IS_ERR(ctx
->io_wq
)) {
6816 ret
= PTR_ERR(ctx
->io_wq
);
6822 f
= fdget(p
->wq_fd
);
6826 if (f
.file
->f_op
!= &io_uring_fops
) {
6831 ctx_attach
= f
.file
->private_data
;
6832 /* @io_wq is protected by holding the fd */
6833 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
6838 ctx
->io_wq
= ctx_attach
->io_wq
;
6844 static int io_sq_offload_start(struct io_ring_ctx
*ctx
,
6845 struct io_uring_params
*p
)
6849 mmgrab(current
->mm
);
6850 ctx
->sqo_mm
= current
->mm
;
6852 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
6854 if (!capable(CAP_SYS_ADMIN
))
6857 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
6858 if (!ctx
->sq_thread_idle
)
6859 ctx
->sq_thread_idle
= HZ
;
6861 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
6862 int cpu
= p
->sq_thread_cpu
;
6865 if (cpu
>= nr_cpu_ids
)
6867 if (!cpu_online(cpu
))
6870 ctx
->sqo_thread
= kthread_create_on_cpu(io_sq_thread
,
6874 ctx
->sqo_thread
= kthread_create(io_sq_thread
, ctx
,
6877 if (IS_ERR(ctx
->sqo_thread
)) {
6878 ret
= PTR_ERR(ctx
->sqo_thread
);
6879 ctx
->sqo_thread
= NULL
;
6882 wake_up_process(ctx
->sqo_thread
);
6883 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
6884 /* Can't have SQ_AFF without SQPOLL */
6889 ret
= io_init_wq_offload(ctx
, p
);
6895 io_finish_async(ctx
);
6896 mmdrop(ctx
->sqo_mm
);
6901 static void io_unaccount_mem(struct user_struct
*user
, unsigned long nr_pages
)
6903 atomic_long_sub(nr_pages
, &user
->locked_vm
);
6906 static int io_account_mem(struct user_struct
*user
, unsigned long nr_pages
)
6908 unsigned long page_limit
, cur_pages
, new_pages
;
6910 /* Don't allow more pages than we can safely lock */
6911 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
6914 cur_pages
= atomic_long_read(&user
->locked_vm
);
6915 new_pages
= cur_pages
+ nr_pages
;
6916 if (new_pages
> page_limit
)
6918 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
6919 new_pages
) != cur_pages
);
6924 static void io_mem_free(void *ptr
)
6931 page
= virt_to_head_page(ptr
);
6932 if (put_page_testzero(page
))
6933 free_compound_page(page
);
6936 static void *io_mem_alloc(size_t size
)
6938 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
6941 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
6944 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
6947 struct io_rings
*rings
;
6948 size_t off
, sq_array_size
;
6950 off
= struct_size(rings
, cqes
, cq_entries
);
6951 if (off
== SIZE_MAX
)
6955 off
= ALIGN(off
, SMP_CACHE_BYTES
);
6960 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
6961 if (sq_array_size
== SIZE_MAX
)
6964 if (check_add_overflow(off
, sq_array_size
, &off
))
6973 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
6977 pages
= (size_t)1 << get_order(
6978 rings_size(sq_entries
, cq_entries
, NULL
));
6979 pages
+= (size_t)1 << get_order(
6980 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
6985 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
6989 if (!ctx
->user_bufs
)
6992 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
6993 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
6995 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
6996 unpin_user_page(imu
->bvec
[j
].bv_page
);
6998 if (ctx
->account_mem
)
6999 io_unaccount_mem(ctx
->user
, imu
->nr_bvecs
);
7004 kfree(ctx
->user_bufs
);
7005 ctx
->user_bufs
= NULL
;
7006 ctx
->nr_user_bufs
= 0;
7010 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
7011 void __user
*arg
, unsigned index
)
7013 struct iovec __user
*src
;
7015 #ifdef CONFIG_COMPAT
7017 struct compat_iovec __user
*ciovs
;
7018 struct compat_iovec ciov
;
7020 ciovs
= (struct compat_iovec __user
*) arg
;
7021 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
7024 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
7025 dst
->iov_len
= ciov
.iov_len
;
7029 src
= (struct iovec __user
*) arg
;
7030 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
7035 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7038 struct vm_area_struct
**vmas
= NULL
;
7039 struct page
**pages
= NULL
;
7040 int i
, j
, got_pages
= 0;
7045 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
7048 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
7050 if (!ctx
->user_bufs
)
7053 for (i
= 0; i
< nr_args
; i
++) {
7054 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7055 unsigned long off
, start
, end
, ubuf
;
7060 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
7065 * Don't impose further limits on the size and buffer
7066 * constraints here, we'll -EINVAL later when IO is
7067 * submitted if they are wrong.
7070 if (!iov
.iov_base
|| !iov
.iov_len
)
7073 /* arbitrary limit, but we need something */
7074 if (iov
.iov_len
> SZ_1G
)
7077 ubuf
= (unsigned long) iov
.iov_base
;
7078 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
7079 start
= ubuf
>> PAGE_SHIFT
;
7080 nr_pages
= end
- start
;
7082 if (ctx
->account_mem
) {
7083 ret
= io_account_mem(ctx
->user
, nr_pages
);
7089 if (!pages
|| nr_pages
> got_pages
) {
7092 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
7094 vmas
= kvmalloc_array(nr_pages
,
7095 sizeof(struct vm_area_struct
*),
7097 if (!pages
|| !vmas
) {
7099 if (ctx
->account_mem
)
7100 io_unaccount_mem(ctx
->user
, nr_pages
);
7103 got_pages
= nr_pages
;
7106 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
7110 if (ctx
->account_mem
)
7111 io_unaccount_mem(ctx
->user
, nr_pages
);
7116 down_read(¤t
->mm
->mmap_sem
);
7117 pret
= pin_user_pages(ubuf
, nr_pages
,
7118 FOLL_WRITE
| FOLL_LONGTERM
,
7120 if (pret
== nr_pages
) {
7121 /* don't support file backed memory */
7122 for (j
= 0; j
< nr_pages
; j
++) {
7123 struct vm_area_struct
*vma
= vmas
[j
];
7126 !is_file_hugepages(vma
->vm_file
)) {
7132 ret
= pret
< 0 ? pret
: -EFAULT
;
7134 up_read(¤t
->mm
->mmap_sem
);
7137 * if we did partial map, or found file backed vmas,
7138 * release any pages we did get
7141 unpin_user_pages(pages
, pret
);
7142 if (ctx
->account_mem
)
7143 io_unaccount_mem(ctx
->user
, nr_pages
);
7148 off
= ubuf
& ~PAGE_MASK
;
7150 for (j
= 0; j
< nr_pages
; j
++) {
7153 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
7154 imu
->bvec
[j
].bv_page
= pages
[j
];
7155 imu
->bvec
[j
].bv_len
= vec_len
;
7156 imu
->bvec
[j
].bv_offset
= off
;
7160 /* store original address for later verification */
7162 imu
->len
= iov
.iov_len
;
7163 imu
->nr_bvecs
= nr_pages
;
7165 ctx
->nr_user_bufs
++;
7173 io_sqe_buffer_unregister(ctx
);
7177 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
7179 __s32 __user
*fds
= arg
;
7185 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
7188 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
7189 if (IS_ERR(ctx
->cq_ev_fd
)) {
7190 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
7191 ctx
->cq_ev_fd
= NULL
;
7198 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
7200 if (ctx
->cq_ev_fd
) {
7201 eventfd_ctx_put(ctx
->cq_ev_fd
);
7202 ctx
->cq_ev_fd
= NULL
;
7209 static int __io_destroy_buffers(int id
, void *p
, void *data
)
7211 struct io_ring_ctx
*ctx
= data
;
7212 struct io_buffer
*buf
= p
;
7214 __io_remove_buffers(ctx
, buf
, id
, -1U);
7218 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
7220 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
7221 idr_destroy(&ctx
->io_buffer_idr
);
7224 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
7226 io_finish_async(ctx
);
7228 mmdrop(ctx
->sqo_mm
);
7230 io_iopoll_reap_events(ctx
);
7231 io_sqe_buffer_unregister(ctx
);
7232 io_sqe_files_unregister(ctx
);
7233 io_eventfd_unregister(ctx
);
7234 io_destroy_buffers(ctx
);
7235 idr_destroy(&ctx
->personality_idr
);
7237 #if defined(CONFIG_UNIX)
7238 if (ctx
->ring_sock
) {
7239 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
7240 sock_release(ctx
->ring_sock
);
7244 io_mem_free(ctx
->rings
);
7245 io_mem_free(ctx
->sq_sqes
);
7247 percpu_ref_exit(&ctx
->refs
);
7248 if (ctx
->account_mem
)
7249 io_unaccount_mem(ctx
->user
,
7250 ring_pages(ctx
->sq_entries
, ctx
->cq_entries
));
7251 free_uid(ctx
->user
);
7252 put_cred(ctx
->creds
);
7253 kfree(ctx
->completions
);
7254 kfree(ctx
->cancel_hash
);
7255 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
7259 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
7261 struct io_ring_ctx
*ctx
= file
->private_data
;
7264 poll_wait(file
, &ctx
->cq_wait
, wait
);
7266 * synchronizes with barrier from wq_has_sleeper call in
7270 if (READ_ONCE(ctx
->rings
->sq
.tail
) - ctx
->cached_sq_head
!=
7271 ctx
->rings
->sq_ring_entries
)
7272 mask
|= EPOLLOUT
| EPOLLWRNORM
;
7273 if (io_cqring_events(ctx
, false))
7274 mask
|= EPOLLIN
| EPOLLRDNORM
;
7279 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
7281 struct io_ring_ctx
*ctx
= file
->private_data
;
7283 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
7286 static int io_remove_personalities(int id
, void *p
, void *data
)
7288 struct io_ring_ctx
*ctx
= data
;
7289 const struct cred
*cred
;
7291 cred
= idr_remove(&ctx
->personality_idr
, id
);
7297 static void io_ring_exit_work(struct work_struct
*work
)
7299 struct io_ring_ctx
*ctx
;
7301 ctx
= container_of(work
, struct io_ring_ctx
, exit_work
);
7303 io_cqring_overflow_flush(ctx
, true);
7305 wait_for_completion(&ctx
->completions
[0]);
7306 io_ring_ctx_free(ctx
);
7309 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
7311 mutex_lock(&ctx
->uring_lock
);
7312 percpu_ref_kill(&ctx
->refs
);
7313 mutex_unlock(&ctx
->uring_lock
);
7316 * Wait for sq thread to idle, if we have one. It won't spin on new
7317 * work after we've killed the ctx ref above. This is important to do
7318 * before we cancel existing commands, as the thread could otherwise
7319 * be queueing new work post that. If that's work we need to cancel,
7320 * it could cause shutdown to hang.
7322 while (ctx
->sqo_thread
&& !wq_has_sleeper(&ctx
->sqo_wait
))
7325 io_kill_timeouts(ctx
);
7326 io_poll_remove_all(ctx
);
7329 io_wq_cancel_all(ctx
->io_wq
);
7331 io_iopoll_reap_events(ctx
);
7332 /* if we failed setting up the ctx, we might not have any rings */
7334 io_cqring_overflow_flush(ctx
, true);
7335 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
7336 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
7337 queue_work(system_wq
, &ctx
->exit_work
);
7340 static int io_uring_release(struct inode
*inode
, struct file
*file
)
7342 struct io_ring_ctx
*ctx
= file
->private_data
;
7344 file
->private_data
= NULL
;
7345 io_ring_ctx_wait_and_kill(ctx
);
7349 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
7350 struct files_struct
*files
)
7352 while (!list_empty_careful(&ctx
->inflight_list
)) {
7353 struct io_kiocb
*cancel_req
= NULL
, *req
;
7356 spin_lock_irq(&ctx
->inflight_lock
);
7357 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
7358 if (req
->work
.files
!= files
)
7360 /* req is being completed, ignore */
7361 if (!refcount_inc_not_zero(&req
->refs
))
7367 prepare_to_wait(&ctx
->inflight_wait
, &wait
,
7368 TASK_UNINTERRUPTIBLE
);
7369 spin_unlock_irq(&ctx
->inflight_lock
);
7371 /* We need to keep going until we don't find a matching req */
7375 if (cancel_req
->flags
& REQ_F_OVERFLOW
) {
7376 spin_lock_irq(&ctx
->completion_lock
);
7377 list_del(&cancel_req
->list
);
7378 cancel_req
->flags
&= ~REQ_F_OVERFLOW
;
7379 if (list_empty(&ctx
->cq_overflow_list
)) {
7380 clear_bit(0, &ctx
->sq_check_overflow
);
7381 clear_bit(0, &ctx
->cq_check_overflow
);
7383 spin_unlock_irq(&ctx
->completion_lock
);
7385 WRITE_ONCE(ctx
->rings
->cq_overflow
,
7386 atomic_inc_return(&ctx
->cached_cq_overflow
));
7389 * Put inflight ref and overflow ref. If that's
7390 * all we had, then we're done with this request.
7392 if (refcount_sub_and_test(2, &cancel_req
->refs
)) {
7393 io_put_req(cancel_req
);
7394 finish_wait(&ctx
->inflight_wait
, &wait
);
7399 io_wq_cancel_work(ctx
->io_wq
, &cancel_req
->work
);
7400 io_put_req(cancel_req
);
7402 finish_wait(&ctx
->inflight_wait
, &wait
);
7406 static int io_uring_flush(struct file
*file
, void *data
)
7408 struct io_ring_ctx
*ctx
= file
->private_data
;
7410 io_uring_cancel_files(ctx
, data
);
7413 * If the task is going away, cancel work it may have pending
7415 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
))
7416 io_wq_cancel_pid(ctx
->io_wq
, task_pid_vnr(current
));
7421 static void *io_uring_validate_mmap_request(struct file
*file
,
7422 loff_t pgoff
, size_t sz
)
7424 struct io_ring_ctx
*ctx
= file
->private_data
;
7425 loff_t offset
= pgoff
<< PAGE_SHIFT
;
7430 case IORING_OFF_SQ_RING
:
7431 case IORING_OFF_CQ_RING
:
7434 case IORING_OFF_SQES
:
7438 return ERR_PTR(-EINVAL
);
7441 page
= virt_to_head_page(ptr
);
7442 if (sz
> page_size(page
))
7443 return ERR_PTR(-EINVAL
);
7450 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
7452 size_t sz
= vma
->vm_end
- vma
->vm_start
;
7456 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
7458 return PTR_ERR(ptr
);
7460 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
7461 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
7464 #else /* !CONFIG_MMU */
7466 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
7468 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
7471 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
7473 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
7476 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
7477 unsigned long addr
, unsigned long len
,
7478 unsigned long pgoff
, unsigned long flags
)
7482 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
7484 return PTR_ERR(ptr
);
7486 return (unsigned long) ptr
;
7489 #endif /* !CONFIG_MMU */
7491 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
7492 u32
, min_complete
, u32
, flags
, const sigset_t __user
*, sig
,
7495 struct io_ring_ctx
*ctx
;
7500 if (current
->task_works
)
7503 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
))
7511 if (f
.file
->f_op
!= &io_uring_fops
)
7515 ctx
= f
.file
->private_data
;
7516 if (!percpu_ref_tryget(&ctx
->refs
))
7520 * For SQ polling, the thread will do all submissions and completions.
7521 * Just return the requested submit count, and wake the thread if
7525 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7526 if (!list_empty_careful(&ctx
->cq_overflow_list
))
7527 io_cqring_overflow_flush(ctx
, false);
7528 if (flags
& IORING_ENTER_SQ_WAKEUP
)
7529 wake_up(&ctx
->sqo_wait
);
7530 submitted
= to_submit
;
7531 } else if (to_submit
) {
7532 mutex_lock(&ctx
->uring_lock
);
7533 submitted
= io_submit_sqes(ctx
, to_submit
, f
.file
, fd
, false);
7534 mutex_unlock(&ctx
->uring_lock
);
7536 if (submitted
!= to_submit
)
7539 if (flags
& IORING_ENTER_GETEVENTS
) {
7540 unsigned nr_events
= 0;
7542 min_complete
= min(min_complete
, ctx
->cq_entries
);
7545 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
7546 * space applications don't need to do io completion events
7547 * polling again, they can rely on io_sq_thread to do polling
7548 * work, which can reduce cpu usage and uring_lock contention.
7550 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
7551 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
7552 ret
= io_iopoll_check(ctx
, &nr_events
, min_complete
);
7554 ret
= io_cqring_wait(ctx
, min_complete
, sig
, sigsz
);
7559 percpu_ref_put(&ctx
->refs
);
7562 return submitted
? submitted
: ret
;
7565 #ifdef CONFIG_PROC_FS
7566 static int io_uring_show_cred(int id
, void *p
, void *data
)
7568 const struct cred
*cred
= p
;
7569 struct seq_file
*m
= data
;
7570 struct user_namespace
*uns
= seq_user_ns(m
);
7571 struct group_info
*gi
;
7576 seq_printf(m
, "%5d\n", id
);
7577 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
7578 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
7579 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
7580 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
7581 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
7582 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
7583 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
7584 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
7585 seq_puts(m
, "\n\tGroups:\t");
7586 gi
= cred
->group_info
;
7587 for (g
= 0; g
< gi
->ngroups
; g
++) {
7588 seq_put_decimal_ull(m
, g
? " " : "",
7589 from_kgid_munged(uns
, gi
->gid
[g
]));
7591 seq_puts(m
, "\n\tCapEff:\t");
7592 cap
= cred
->cap_effective
;
7593 CAP_FOR_EACH_U32(__capi
)
7594 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
7599 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
7603 mutex_lock(&ctx
->uring_lock
);
7604 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
7605 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7606 struct fixed_file_table
*table
;
7609 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7610 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
7612 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
7614 seq_printf(m
, "%5u: <none>\n", i
);
7616 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
7617 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7618 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
7620 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
7621 (unsigned int) buf
->len
);
7623 if (!idr_is_empty(&ctx
->personality_idr
)) {
7624 seq_printf(m
, "Personalities:\n");
7625 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
7627 seq_printf(m
, "PollList:\n");
7628 spin_lock_irq(&ctx
->completion_lock
);
7629 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
7630 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
7631 struct io_kiocb
*req
;
7633 hlist_for_each_entry(req
, list
, hash_node
)
7634 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
7635 req
->task
->task_works
!= NULL
);
7637 spin_unlock_irq(&ctx
->completion_lock
);
7638 mutex_unlock(&ctx
->uring_lock
);
7641 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
7643 struct io_ring_ctx
*ctx
= f
->private_data
;
7645 if (percpu_ref_tryget(&ctx
->refs
)) {
7646 __io_uring_show_fdinfo(ctx
, m
);
7647 percpu_ref_put(&ctx
->refs
);
7652 static const struct file_operations io_uring_fops
= {
7653 .release
= io_uring_release
,
7654 .flush
= io_uring_flush
,
7655 .mmap
= io_uring_mmap
,
7657 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
7658 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
7660 .poll
= io_uring_poll
,
7661 .fasync
= io_uring_fasync
,
7662 #ifdef CONFIG_PROC_FS
7663 .show_fdinfo
= io_uring_show_fdinfo
,
7667 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
7668 struct io_uring_params
*p
)
7670 struct io_rings
*rings
;
7671 size_t size
, sq_array_offset
;
7673 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
7674 if (size
== SIZE_MAX
)
7677 rings
= io_mem_alloc(size
);
7682 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
7683 rings
->sq_ring_mask
= p
->sq_entries
- 1;
7684 rings
->cq_ring_mask
= p
->cq_entries
- 1;
7685 rings
->sq_ring_entries
= p
->sq_entries
;
7686 rings
->cq_ring_entries
= p
->cq_entries
;
7687 ctx
->sq_mask
= rings
->sq_ring_mask
;
7688 ctx
->cq_mask
= rings
->cq_ring_mask
;
7689 ctx
->sq_entries
= rings
->sq_ring_entries
;
7690 ctx
->cq_entries
= rings
->cq_ring_entries
;
7692 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
7693 if (size
== SIZE_MAX
) {
7694 io_mem_free(ctx
->rings
);
7699 ctx
->sq_sqes
= io_mem_alloc(size
);
7700 if (!ctx
->sq_sqes
) {
7701 io_mem_free(ctx
->rings
);
7710 * Allocate an anonymous fd, this is what constitutes the application
7711 * visible backing of an io_uring instance. The application mmaps this
7712 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
7713 * we have to tie this fd to a socket for file garbage collection purposes.
7715 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
7720 #if defined(CONFIG_UNIX)
7721 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
7727 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
7731 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
7732 O_RDWR
| O_CLOEXEC
);
7735 ret
= PTR_ERR(file
);
7739 #if defined(CONFIG_UNIX)
7740 ctx
->ring_sock
->file
= file
;
7742 fd_install(ret
, file
);
7745 #if defined(CONFIG_UNIX)
7746 sock_release(ctx
->ring_sock
);
7747 ctx
->ring_sock
= NULL
;
7752 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
7753 struct io_uring_params __user
*params
)
7755 struct user_struct
*user
= NULL
;
7756 struct io_ring_ctx
*ctx
;
7762 if (entries
> IORING_MAX_ENTRIES
) {
7763 if (!(p
->flags
& IORING_SETUP_CLAMP
))
7765 entries
= IORING_MAX_ENTRIES
;
7769 * Use twice as many entries for the CQ ring. It's possible for the
7770 * application to drive a higher depth than the size of the SQ ring,
7771 * since the sqes are only used at submission time. This allows for
7772 * some flexibility in overcommitting a bit. If the application has
7773 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
7774 * of CQ ring entries manually.
7776 p
->sq_entries
= roundup_pow_of_two(entries
);
7777 if (p
->flags
& IORING_SETUP_CQSIZE
) {
7779 * If IORING_SETUP_CQSIZE is set, we do the same roundup
7780 * to a power-of-two, if it isn't already. We do NOT impose
7781 * any cq vs sq ring sizing.
7783 if (p
->cq_entries
< p
->sq_entries
)
7785 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
7786 if (!(p
->flags
& IORING_SETUP_CLAMP
))
7788 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
7790 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
7792 p
->cq_entries
= 2 * p
->sq_entries
;
7795 user
= get_uid(current_user());
7796 account_mem
= !capable(CAP_IPC_LOCK
);
7799 ret
= io_account_mem(user
,
7800 ring_pages(p
->sq_entries
, p
->cq_entries
));
7807 ctx
= io_ring_ctx_alloc(p
);
7810 io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
7815 ctx
->compat
= in_compat_syscall();
7816 ctx
->account_mem
= account_mem
;
7818 ctx
->creds
= get_current_cred();
7820 ret
= io_allocate_scq_urings(ctx
, p
);
7824 ret
= io_sq_offload_start(ctx
, p
);
7828 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
7829 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
7830 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
7831 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
7832 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
7833 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
7834 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
7835 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
7837 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
7838 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
7839 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
7840 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
7841 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
7842 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
7843 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
7845 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
7846 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
7847 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
;
7849 if (copy_to_user(params
, p
, sizeof(*p
))) {
7854 * Install ring fd as the very last thing, so we don't risk someone
7855 * having closed it before we finish setup
7857 ret
= io_uring_get_fd(ctx
);
7861 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
7864 io_ring_ctx_wait_and_kill(ctx
);
7869 * Sets up an aio uring context, and returns the fd. Applications asks for a
7870 * ring size, we return the actual sq/cq ring sizes (among other things) in the
7871 * params structure passed in.
7873 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
7875 struct io_uring_params p
;
7878 if (copy_from_user(&p
, params
, sizeof(p
)))
7880 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
7885 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
7886 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
7887 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
))
7890 return io_uring_create(entries
, &p
, params
);
7893 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
7894 struct io_uring_params __user
*, params
)
7896 return io_uring_setup(entries
, params
);
7899 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
7901 struct io_uring_probe
*p
;
7905 size
= struct_size(p
, ops
, nr_args
);
7906 if (size
== SIZE_MAX
)
7908 p
= kzalloc(size
, GFP_KERNEL
);
7913 if (copy_from_user(p
, arg
, size
))
7916 if (memchr_inv(p
, 0, size
))
7919 p
->last_op
= IORING_OP_LAST
- 1;
7920 if (nr_args
> IORING_OP_LAST
)
7921 nr_args
= IORING_OP_LAST
;
7923 for (i
= 0; i
< nr_args
; i
++) {
7925 if (!io_op_defs
[i
].not_supported
)
7926 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
7931 if (copy_to_user(arg
, p
, size
))
7938 static int io_register_personality(struct io_ring_ctx
*ctx
)
7940 const struct cred
*creds
= get_current_cred();
7943 id
= idr_alloc_cyclic(&ctx
->personality_idr
, (void *) creds
, 1,
7944 USHRT_MAX
, GFP_KERNEL
);
7950 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
7952 const struct cred
*old_creds
;
7954 old_creds
= idr_remove(&ctx
->personality_idr
, id
);
7956 put_cred(old_creds
);
7963 static bool io_register_op_must_quiesce(int op
)
7966 case IORING_UNREGISTER_FILES
:
7967 case IORING_REGISTER_FILES_UPDATE
:
7968 case IORING_REGISTER_PROBE
:
7969 case IORING_REGISTER_PERSONALITY
:
7970 case IORING_UNREGISTER_PERSONALITY
:
7977 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
7978 void __user
*arg
, unsigned nr_args
)
7979 __releases(ctx
->uring_lock
)
7980 __acquires(ctx
->uring_lock
)
7985 * We're inside the ring mutex, if the ref is already dying, then
7986 * someone else killed the ctx or is already going through
7987 * io_uring_register().
7989 if (percpu_ref_is_dying(&ctx
->refs
))
7992 if (io_register_op_must_quiesce(opcode
)) {
7993 percpu_ref_kill(&ctx
->refs
);
7996 * Drop uring mutex before waiting for references to exit. If
7997 * another thread is currently inside io_uring_enter() it might
7998 * need to grab the uring_lock to make progress. If we hold it
7999 * here across the drain wait, then we can deadlock. It's safe
8000 * to drop the mutex here, since no new references will come in
8001 * after we've killed the percpu ref.
8003 mutex_unlock(&ctx
->uring_lock
);
8004 ret
= wait_for_completion_interruptible(&ctx
->completions
[0]);
8005 mutex_lock(&ctx
->uring_lock
);
8007 percpu_ref_resurrect(&ctx
->refs
);
8014 case IORING_REGISTER_BUFFERS
:
8015 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
8017 case IORING_UNREGISTER_BUFFERS
:
8021 ret
= io_sqe_buffer_unregister(ctx
);
8023 case IORING_REGISTER_FILES
:
8024 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
8026 case IORING_UNREGISTER_FILES
:
8030 ret
= io_sqe_files_unregister(ctx
);
8032 case IORING_REGISTER_FILES_UPDATE
:
8033 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
8035 case IORING_REGISTER_EVENTFD
:
8036 case IORING_REGISTER_EVENTFD_ASYNC
:
8040 ret
= io_eventfd_register(ctx
, arg
);
8043 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
8044 ctx
->eventfd_async
= 1;
8046 ctx
->eventfd_async
= 0;
8048 case IORING_UNREGISTER_EVENTFD
:
8052 ret
= io_eventfd_unregister(ctx
);
8054 case IORING_REGISTER_PROBE
:
8056 if (!arg
|| nr_args
> 256)
8058 ret
= io_probe(ctx
, arg
, nr_args
);
8060 case IORING_REGISTER_PERSONALITY
:
8064 ret
= io_register_personality(ctx
);
8066 case IORING_UNREGISTER_PERSONALITY
:
8070 ret
= io_unregister_personality(ctx
, nr_args
);
8077 if (io_register_op_must_quiesce(opcode
)) {
8078 /* bring the ctx back to life */
8079 percpu_ref_reinit(&ctx
->refs
);
8081 reinit_completion(&ctx
->completions
[0]);
8086 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
8087 void __user
*, arg
, unsigned int, nr_args
)
8089 struct io_ring_ctx
*ctx
;
8098 if (f
.file
->f_op
!= &io_uring_fops
)
8101 ctx
= f
.file
->private_data
;
8103 mutex_lock(&ctx
->uring_lock
);
8104 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
8105 mutex_unlock(&ctx
->uring_lock
);
8106 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
8107 ctx
->cq_ev_fd
!= NULL
, ret
);
8113 static int __init
io_uring_init(void)
8115 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
8116 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
8117 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
8120 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
8121 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
8122 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
8123 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
8124 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
8125 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
8126 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
8127 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
8128 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
8129 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
8130 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
8131 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
8132 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
8133 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
8134 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
8135 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
8136 BUILD_BUG_SQE_ELEM(28, __u16
, poll_events
);
8137 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
8138 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
8139 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
8140 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
8141 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
8142 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
8143 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
8144 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
8145 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
8146 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
8147 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
8148 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
8149 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
8151 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
8152 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
8153 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
8156 __initcall(io_uring_init
);