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.
157 * Written by the application, shouldn't be modified by the
162 * Number of completion events lost because the queue was full;
163 * this should be avoided by the application by making sure
164 * there are not more requests pending than there is space in
165 * the completion queue.
167 * Written by the kernel, shouldn't be modified by the
168 * application (i.e. get number of "new events" by comparing to
171 * As completion events come in out of order this counter is not
172 * ordered with any other data.
176 * Ring buffer of completion events.
178 * The kernel writes completion events fresh every time they are
179 * produced, so the application is allowed to modify pending
182 struct io_uring_cqe cqes
[] ____cacheline_aligned_in_smp
;
185 struct io_mapped_ubuf
{
188 struct bio_vec
*bvec
;
189 unsigned int nr_bvecs
;
192 struct fixed_file_table
{
196 struct fixed_file_ref_node
{
197 struct percpu_ref refs
;
198 struct list_head node
;
199 struct list_head file_list
;
200 struct fixed_file_data
*file_data
;
201 struct llist_node llist
;
204 struct fixed_file_data
{
205 struct fixed_file_table
*table
;
206 struct io_ring_ctx
*ctx
;
208 struct percpu_ref
*cur_refs
;
209 struct percpu_ref refs
;
210 struct completion done
;
211 struct list_head ref_list
;
216 struct list_head list
;
224 struct percpu_ref refs
;
225 } ____cacheline_aligned_in_smp
;
229 unsigned int compat
: 1;
230 unsigned int account_mem
: 1;
231 unsigned int cq_overflow_flushed
: 1;
232 unsigned int drain_next
: 1;
233 unsigned int eventfd_async
: 1;
236 * Ring buffer of indices into array of io_uring_sqe, which is
237 * mmapped by the application using the IORING_OFF_SQES offset.
239 * This indirection could e.g. be used to assign fixed
240 * io_uring_sqe entries to operations and only submit them to
241 * the queue when needed.
243 * The kernel modifies neither the indices array nor the entries
247 unsigned cached_sq_head
;
250 unsigned sq_thread_idle
;
251 unsigned cached_sq_dropped
;
252 atomic_t cached_cq_overflow
;
253 unsigned long sq_check_overflow
;
255 struct list_head defer_list
;
256 struct list_head timeout_list
;
257 struct list_head cq_overflow_list
;
259 wait_queue_head_t inflight_wait
;
260 struct io_uring_sqe
*sq_sqes
;
261 } ____cacheline_aligned_in_smp
;
263 struct io_rings
*rings
;
267 struct task_struct
*sqo_thread
; /* if using sq thread polling */
268 struct mm_struct
*sqo_mm
;
269 wait_queue_head_t sqo_wait
;
272 * If used, fixed file set. Writers must ensure that ->refs is dead,
273 * readers must ensure that ->refs is alive as long as the file* is
274 * used. Only updated through io_uring_register(2).
276 struct fixed_file_data
*file_data
;
277 unsigned nr_user_files
;
279 struct file
*ring_file
;
281 /* if used, fixed mapped user buffers */
282 unsigned nr_user_bufs
;
283 struct io_mapped_ubuf
*user_bufs
;
285 struct user_struct
*user
;
287 const struct cred
*creds
;
289 struct completion ref_comp
;
290 struct completion sq_thread_comp
;
292 /* if all else fails... */
293 struct io_kiocb
*fallback_req
;
295 #if defined(CONFIG_UNIX)
296 struct socket
*ring_sock
;
299 struct idr io_buffer_idr
;
301 struct idr personality_idr
;
304 unsigned cached_cq_tail
;
307 atomic_t cq_timeouts
;
308 unsigned long cq_check_overflow
;
309 struct wait_queue_head cq_wait
;
310 struct fasync_struct
*cq_fasync
;
311 struct eventfd_ctx
*cq_ev_fd
;
312 } ____cacheline_aligned_in_smp
;
315 struct mutex uring_lock
;
316 wait_queue_head_t wait
;
317 } ____cacheline_aligned_in_smp
;
320 spinlock_t completion_lock
;
323 * ->poll_list is protected by the ctx->uring_lock for
324 * io_uring instances that don't use IORING_SETUP_SQPOLL.
325 * For SQPOLL, only the single threaded io_sq_thread() will
326 * manipulate the list, hence no extra locking is needed there.
328 struct list_head poll_list
;
329 struct hlist_head
*cancel_hash
;
330 unsigned cancel_hash_bits
;
331 bool poll_multi_file
;
333 spinlock_t inflight_lock
;
334 struct list_head inflight_list
;
335 } ____cacheline_aligned_in_smp
;
337 struct delayed_work file_put_work
;
338 struct llist_head file_put_llist
;
340 struct work_struct exit_work
;
344 * First field must be the file pointer in all the
345 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
347 struct io_poll_iocb
{
350 struct wait_queue_head
*head
;
356 struct wait_queue_entry wait
;
361 struct file
*put_file
;
365 struct io_timeout_data
{
366 struct io_kiocb
*req
;
367 struct hrtimer timer
;
368 struct timespec64 ts
;
369 enum hrtimer_mode mode
;
374 struct sockaddr __user
*addr
;
375 int __user
*addr_len
;
377 unsigned long nofile
;
402 /* NOTE: kiocb has the file as the first member, so don't do it here */
410 struct sockaddr __user
*addr
;
417 struct user_msghdr __user
*msg
;
423 struct io_buffer
*kbuf
;
429 struct filename
*filename
;
431 unsigned long nofile
;
434 struct io_files_update
{
460 struct epoll_event event
;
464 struct file
*file_out
;
465 struct file
*file_in
;
472 struct io_provide_buf
{
486 const char __user
*filename
;
487 struct statx __user
*buffer
;
490 struct io_async_connect
{
491 struct sockaddr_storage address
;
494 struct io_async_msghdr
{
495 struct iovec fast_iov
[UIO_FASTIOV
];
497 struct sockaddr __user
*uaddr
;
499 struct sockaddr_storage addr
;
503 struct iovec fast_iov
[UIO_FASTIOV
];
509 struct io_async_ctx
{
511 struct io_async_rw rw
;
512 struct io_async_msghdr msg
;
513 struct io_async_connect connect
;
514 struct io_timeout_data timeout
;
519 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
520 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
521 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
522 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
523 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
524 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
532 REQ_F_IOPOLL_COMPLETED_BIT
,
533 REQ_F_LINK_TIMEOUT_BIT
,
537 REQ_F_TIMEOUT_NOSEQ_BIT
,
538 REQ_F_COMP_LOCKED_BIT
,
539 REQ_F_NEED_CLEANUP_BIT
,
542 REQ_F_BUFFER_SELECTED_BIT
,
543 REQ_F_NO_FILE_TABLE_BIT
,
545 /* not a real bit, just to check we're not overflowing the space */
551 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
552 /* drain existing IO first */
553 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
555 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
556 /* doesn't sever on completion < 0 */
557 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
559 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
560 /* IOSQE_BUFFER_SELECT */
561 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
564 REQ_F_LINK_HEAD
= BIT(REQ_F_LINK_HEAD_BIT
),
565 /* already grabbed next link */
566 REQ_F_LINK_NEXT
= BIT(REQ_F_LINK_NEXT_BIT
),
567 /* fail rest of links */
568 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
569 /* on inflight list */
570 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
571 /* read/write uses file position */
572 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
573 /* must not punt to workers */
574 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
575 /* polled IO has completed */
576 REQ_F_IOPOLL_COMPLETED
= BIT(REQ_F_IOPOLL_COMPLETED_BIT
),
577 /* has linked timeout */
578 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
579 /* timeout request */
580 REQ_F_TIMEOUT
= BIT(REQ_F_TIMEOUT_BIT
),
582 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
583 /* must be punted even for NONBLOCK */
584 REQ_F_MUST_PUNT
= BIT(REQ_F_MUST_PUNT_BIT
),
585 /* no timeout sequence */
586 REQ_F_TIMEOUT_NOSEQ
= BIT(REQ_F_TIMEOUT_NOSEQ_BIT
),
587 /* completion under lock */
588 REQ_F_COMP_LOCKED
= BIT(REQ_F_COMP_LOCKED_BIT
),
590 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
591 /* in overflow list */
592 REQ_F_OVERFLOW
= BIT(REQ_F_OVERFLOW_BIT
),
593 /* already went through poll handler */
594 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
595 /* buffer already selected */
596 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
597 /* doesn't need file table for this request */
598 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
602 struct io_poll_iocb poll
;
603 struct io_wq_work work
;
607 * NOTE! Each of the iocb union members has the file pointer
608 * as the first entry in their struct definition. So you can
609 * access the file pointer through any of the sub-structs,
610 * or directly as just 'ki_filp' in this struct.
616 struct io_poll_iocb poll
;
617 struct io_accept accept
;
619 struct io_cancel cancel
;
620 struct io_timeout timeout
;
621 struct io_connect connect
;
622 struct io_sr_msg sr_msg
;
624 struct io_close close
;
625 struct io_files_update files_update
;
626 struct io_fadvise fadvise
;
627 struct io_madvise madvise
;
628 struct io_epoll epoll
;
629 struct io_splice splice
;
630 struct io_provide_buf pbuf
;
631 struct io_statx statx
;
634 struct io_async_ctx
*io
;
640 struct io_ring_ctx
*ctx
;
641 struct list_head list
;
644 struct task_struct
*task
;
650 struct list_head link_list
;
652 struct list_head inflight_entry
;
654 struct percpu_ref
*fixed_file_refs
;
658 * Only commands that never go async can use the below fields,
659 * obviously. Right now only IORING_OP_POLL_ADD uses them, and
660 * async armed poll handlers for regular commands. The latter
661 * restore the work, if needed.
664 struct callback_head task_work
;
665 struct hlist_node hash_node
;
666 struct async_poll
*apoll
;
668 struct io_wq_work work
;
672 #define IO_PLUG_THRESHOLD 2
673 #define IO_IOPOLL_BATCH 8
675 struct io_submit_state
{
676 struct blk_plug plug
;
679 * io_kiocb alloc cache
681 void *reqs
[IO_IOPOLL_BATCH
];
682 unsigned int free_reqs
;
685 * File reference cache
689 unsigned int has_refs
;
690 unsigned int used_refs
;
691 unsigned int ios_left
;
695 /* needs req->io allocated for deferral/async */
696 unsigned async_ctx
: 1;
697 /* needs current->mm setup, does mm access */
698 unsigned needs_mm
: 1;
699 /* needs req->file assigned */
700 unsigned needs_file
: 1;
701 /* hash wq insertion if file is a regular file */
702 unsigned hash_reg_file
: 1;
703 /* unbound wq insertion if file is a non-regular file */
704 unsigned unbound_nonreg_file
: 1;
705 /* opcode is not supported by this kernel */
706 unsigned not_supported
: 1;
707 /* needs file table */
708 unsigned file_table
: 1;
710 unsigned needs_fs
: 1;
711 /* set if opcode supports polled "wait" */
713 unsigned pollout
: 1;
714 /* op supports buffer selection */
715 unsigned buffer_select
: 1;
718 static const struct io_op_def io_op_defs
[] = {
719 [IORING_OP_NOP
] = {},
720 [IORING_OP_READV
] = {
724 .unbound_nonreg_file
= 1,
728 [IORING_OP_WRITEV
] = {
733 .unbound_nonreg_file
= 1,
736 [IORING_OP_FSYNC
] = {
739 [IORING_OP_READ_FIXED
] = {
741 .unbound_nonreg_file
= 1,
744 [IORING_OP_WRITE_FIXED
] = {
747 .unbound_nonreg_file
= 1,
750 [IORING_OP_POLL_ADD
] = {
752 .unbound_nonreg_file
= 1,
754 [IORING_OP_POLL_REMOVE
] = {},
755 [IORING_OP_SYNC_FILE_RANGE
] = {
758 [IORING_OP_SENDMSG
] = {
762 .unbound_nonreg_file
= 1,
766 [IORING_OP_RECVMSG
] = {
770 .unbound_nonreg_file
= 1,
775 [IORING_OP_TIMEOUT
] = {
779 [IORING_OP_TIMEOUT_REMOVE
] = {},
780 [IORING_OP_ACCEPT
] = {
783 .unbound_nonreg_file
= 1,
787 [IORING_OP_ASYNC_CANCEL
] = {},
788 [IORING_OP_LINK_TIMEOUT
] = {
792 [IORING_OP_CONNECT
] = {
796 .unbound_nonreg_file
= 1,
799 [IORING_OP_FALLOCATE
] = {
802 [IORING_OP_OPENAT
] = {
806 [IORING_OP_CLOSE
] = {
809 [IORING_OP_FILES_UPDATE
] = {
813 [IORING_OP_STATX
] = {
821 .unbound_nonreg_file
= 1,
825 [IORING_OP_WRITE
] = {
828 .unbound_nonreg_file
= 1,
831 [IORING_OP_FADVISE
] = {
834 [IORING_OP_MADVISE
] = {
840 .unbound_nonreg_file
= 1,
846 .unbound_nonreg_file
= 1,
850 [IORING_OP_OPENAT2
] = {
854 [IORING_OP_EPOLL_CTL
] = {
855 .unbound_nonreg_file
= 1,
858 [IORING_OP_SPLICE
] = {
861 .unbound_nonreg_file
= 1,
863 [IORING_OP_PROVIDE_BUFFERS
] = {},
864 [IORING_OP_REMOVE_BUFFERS
] = {},
868 .unbound_nonreg_file
= 1,
872 static void io_wq_submit_work(struct io_wq_work
**workptr
);
873 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
874 static void io_put_req(struct io_kiocb
*req
);
875 static void __io_double_put_req(struct io_kiocb
*req
);
876 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
877 static void io_queue_linked_timeout(struct io_kiocb
*req
);
878 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
879 struct io_uring_files_update
*ip
,
881 static int io_grab_files(struct io_kiocb
*req
);
882 static void io_cleanup_req(struct io_kiocb
*req
);
883 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
884 int fd
, struct file
**out_file
, bool fixed
);
885 static void __io_queue_sqe(struct io_kiocb
*req
,
886 const struct io_uring_sqe
*sqe
);
888 static struct kmem_cache
*req_cachep
;
890 static const struct file_operations io_uring_fops
;
892 struct sock
*io_uring_get_socket(struct file
*file
)
894 #if defined(CONFIG_UNIX)
895 if (file
->f_op
== &io_uring_fops
) {
896 struct io_ring_ctx
*ctx
= file
->private_data
;
898 return ctx
->ring_sock
->sk
;
903 EXPORT_SYMBOL(io_uring_get_socket
);
905 static void io_file_put_work(struct work_struct
*work
);
907 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
909 return ctx
->flags
& IORING_SETUP_SQPOLL
;
912 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
914 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
916 complete(&ctx
->ref_comp
);
919 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
921 struct io_ring_ctx
*ctx
;
924 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
928 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
929 if (!ctx
->fallback_req
)
933 * Use 5 bits less than the max cq entries, that should give us around
934 * 32 entries per hash list if totally full and uniformly spread.
936 hash_bits
= ilog2(p
->cq_entries
);
940 ctx
->cancel_hash_bits
= hash_bits
;
941 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
943 if (!ctx
->cancel_hash
)
945 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
947 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
948 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
951 ctx
->flags
= p
->flags
;
952 init_waitqueue_head(&ctx
->sqo_wait
);
953 init_waitqueue_head(&ctx
->cq_wait
);
954 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
955 init_completion(&ctx
->ref_comp
);
956 init_completion(&ctx
->sq_thread_comp
);
957 idr_init(&ctx
->io_buffer_idr
);
958 idr_init(&ctx
->personality_idr
);
959 mutex_init(&ctx
->uring_lock
);
960 init_waitqueue_head(&ctx
->wait
);
961 spin_lock_init(&ctx
->completion_lock
);
962 INIT_LIST_HEAD(&ctx
->poll_list
);
963 INIT_LIST_HEAD(&ctx
->defer_list
);
964 INIT_LIST_HEAD(&ctx
->timeout_list
);
965 init_waitqueue_head(&ctx
->inflight_wait
);
966 spin_lock_init(&ctx
->inflight_lock
);
967 INIT_LIST_HEAD(&ctx
->inflight_list
);
968 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
969 init_llist_head(&ctx
->file_put_llist
);
972 if (ctx
->fallback_req
)
973 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
974 kfree(ctx
->cancel_hash
);
979 static inline bool __req_need_defer(struct io_kiocb
*req
)
981 struct io_ring_ctx
*ctx
= req
->ctx
;
983 return req
->sequence
!= ctx
->cached_cq_tail
984 + atomic_read(&ctx
->cached_cq_overflow
);
987 static inline bool req_need_defer(struct io_kiocb
*req
)
989 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
))
990 return __req_need_defer(req
);
995 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
997 struct io_rings
*rings
= ctx
->rings
;
999 /* order cqe stores with ring update */
1000 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1002 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1003 wake_up_interruptible(&ctx
->cq_wait
);
1004 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1008 static inline void io_req_work_grab_env(struct io_kiocb
*req
,
1009 const struct io_op_def
*def
)
1011 if (!req
->work
.mm
&& def
->needs_mm
) {
1012 mmgrab(current
->mm
);
1013 req
->work
.mm
= current
->mm
;
1015 if (!req
->work
.creds
)
1016 req
->work
.creds
= get_current_cred();
1017 if (!req
->work
.fs
&& def
->needs_fs
) {
1018 spin_lock(¤t
->fs
->lock
);
1019 if (!current
->fs
->in_exec
) {
1020 req
->work
.fs
= current
->fs
;
1021 req
->work
.fs
->users
++;
1023 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1025 spin_unlock(¤t
->fs
->lock
);
1027 if (!req
->work
.task_pid
)
1028 req
->work
.task_pid
= task_pid_vnr(current
);
1031 static inline void io_req_work_drop_env(struct io_kiocb
*req
)
1034 mmdrop(req
->work
.mm
);
1035 req
->work
.mm
= NULL
;
1037 if (req
->work
.creds
) {
1038 put_cred(req
->work
.creds
);
1039 req
->work
.creds
= NULL
;
1042 struct fs_struct
*fs
= req
->work
.fs
;
1044 spin_lock(&req
->work
.fs
->lock
);
1047 spin_unlock(&req
->work
.fs
->lock
);
1053 static inline void io_prep_async_work(struct io_kiocb
*req
,
1054 struct io_kiocb
**link
)
1056 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1058 if (req
->flags
& REQ_F_ISREG
) {
1059 if (def
->hash_reg_file
)
1060 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1062 if (def
->unbound_nonreg_file
)
1063 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1066 io_req_work_grab_env(req
, def
);
1068 *link
= io_prep_linked_timeout(req
);
1071 static inline void io_queue_async_work(struct io_kiocb
*req
)
1073 struct io_ring_ctx
*ctx
= req
->ctx
;
1074 struct io_kiocb
*link
;
1076 io_prep_async_work(req
, &link
);
1078 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1079 &req
->work
, req
->flags
);
1080 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1083 io_queue_linked_timeout(link
);
1086 static void io_kill_timeout(struct io_kiocb
*req
)
1090 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1092 atomic_inc(&req
->ctx
->cq_timeouts
);
1093 list_del_init(&req
->list
);
1094 req
->flags
|= REQ_F_COMP_LOCKED
;
1095 io_cqring_fill_event(req
, 0);
1100 static void io_kill_timeouts(struct io_ring_ctx
*ctx
)
1102 struct io_kiocb
*req
, *tmp
;
1104 spin_lock_irq(&ctx
->completion_lock
);
1105 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, list
)
1106 io_kill_timeout(req
);
1107 spin_unlock_irq(&ctx
->completion_lock
);
1110 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1113 struct io_kiocb
*req
= list_first_entry(&ctx
->defer_list
,
1114 struct io_kiocb
, list
);
1116 if (req_need_defer(req
))
1118 list_del_init(&req
->list
);
1119 io_queue_async_work(req
);
1120 } while (!list_empty(&ctx
->defer_list
));
1123 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1125 while (!list_empty(&ctx
->timeout_list
)) {
1126 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1127 struct io_kiocb
, list
);
1129 if (req
->flags
& REQ_F_TIMEOUT_NOSEQ
)
1131 if (req
->timeout
.target_seq
!= ctx
->cached_cq_tail
1132 - atomic_read(&ctx
->cq_timeouts
))
1135 list_del_init(&req
->list
);
1136 io_kill_timeout(req
);
1140 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1142 io_flush_timeouts(ctx
);
1143 __io_commit_cqring(ctx
);
1145 if (unlikely(!list_empty(&ctx
->defer_list
)))
1146 __io_queue_deferred(ctx
);
1149 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1151 struct io_rings
*rings
= ctx
->rings
;
1154 tail
= ctx
->cached_cq_tail
;
1156 * writes to the cq entry need to come after reading head; the
1157 * control dependency is enough as we're using WRITE_ONCE to
1160 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1163 ctx
->cached_cq_tail
++;
1164 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1167 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1171 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1173 if (!ctx
->eventfd_async
)
1175 return io_wq_current_is_worker();
1178 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1180 if (waitqueue_active(&ctx
->wait
))
1181 wake_up(&ctx
->wait
);
1182 if (waitqueue_active(&ctx
->sqo_wait
))
1183 wake_up(&ctx
->sqo_wait
);
1184 if (io_should_trigger_evfd(ctx
))
1185 eventfd_signal(ctx
->cq_ev_fd
, 1);
1188 /* Returns true if there are no backlogged entries after the flush */
1189 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1191 struct io_rings
*rings
= ctx
->rings
;
1192 struct io_uring_cqe
*cqe
;
1193 struct io_kiocb
*req
;
1194 unsigned long flags
;
1198 if (list_empty_careful(&ctx
->cq_overflow_list
))
1200 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1201 rings
->cq_ring_entries
))
1205 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1207 /* if force is set, the ring is going away. always drop after that */
1209 ctx
->cq_overflow_flushed
= 1;
1212 while (!list_empty(&ctx
->cq_overflow_list
)) {
1213 cqe
= io_get_cqring(ctx
);
1217 req
= list_first_entry(&ctx
->cq_overflow_list
, struct io_kiocb
,
1219 list_move(&req
->list
, &list
);
1220 req
->flags
&= ~REQ_F_OVERFLOW
;
1222 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1223 WRITE_ONCE(cqe
->res
, req
->result
);
1224 WRITE_ONCE(cqe
->flags
, req
->cflags
);
1226 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1227 atomic_inc_return(&ctx
->cached_cq_overflow
));
1231 io_commit_cqring(ctx
);
1233 clear_bit(0, &ctx
->sq_check_overflow
);
1234 clear_bit(0, &ctx
->cq_check_overflow
);
1236 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1237 io_cqring_ev_posted(ctx
);
1239 while (!list_empty(&list
)) {
1240 req
= list_first_entry(&list
, struct io_kiocb
, list
);
1241 list_del(&req
->list
);
1248 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1250 struct io_ring_ctx
*ctx
= req
->ctx
;
1251 struct io_uring_cqe
*cqe
;
1253 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1256 * If we can't get a cq entry, userspace overflowed the
1257 * submission (by quite a lot). Increment the overflow count in
1260 cqe
= io_get_cqring(ctx
);
1262 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1263 WRITE_ONCE(cqe
->res
, res
);
1264 WRITE_ONCE(cqe
->flags
, cflags
);
1265 } else if (ctx
->cq_overflow_flushed
) {
1266 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1267 atomic_inc_return(&ctx
->cached_cq_overflow
));
1269 if (list_empty(&ctx
->cq_overflow_list
)) {
1270 set_bit(0, &ctx
->sq_check_overflow
);
1271 set_bit(0, &ctx
->cq_check_overflow
);
1273 req
->flags
|= REQ_F_OVERFLOW
;
1274 refcount_inc(&req
->refs
);
1276 req
->cflags
= cflags
;
1277 list_add_tail(&req
->list
, &ctx
->cq_overflow_list
);
1281 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1283 __io_cqring_fill_event(req
, res
, 0);
1286 static void __io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1288 struct io_ring_ctx
*ctx
= req
->ctx
;
1289 unsigned long flags
;
1291 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1292 __io_cqring_fill_event(req
, res
, cflags
);
1293 io_commit_cqring(ctx
);
1294 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1296 io_cqring_ev_posted(ctx
);
1299 static void io_cqring_add_event(struct io_kiocb
*req
, long res
)
1301 __io_cqring_add_event(req
, res
, 0);
1304 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1306 return req
== (struct io_kiocb
*)
1307 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1310 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1312 struct io_kiocb
*req
;
1314 req
= ctx
->fallback_req
;
1315 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1321 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1322 struct io_submit_state
*state
)
1324 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1325 struct io_kiocb
*req
;
1328 req
= kmem_cache_alloc(req_cachep
, gfp
);
1331 } else if (!state
->free_reqs
) {
1335 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1336 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1339 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1340 * retry single alloc to be on the safe side.
1342 if (unlikely(ret
<= 0)) {
1343 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1344 if (!state
->reqs
[0])
1348 state
->free_reqs
= ret
- 1;
1349 req
= state
->reqs
[ret
- 1];
1352 req
= state
->reqs
[state
->free_reqs
];
1357 return io_get_fallback_req(ctx
);
1360 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1364 percpu_ref_put(req
->fixed_file_refs
);
1369 static void __io_req_aux_free(struct io_kiocb
*req
)
1371 if (req
->flags
& REQ_F_NEED_CLEANUP
)
1372 io_cleanup_req(req
);
1376 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1378 put_task_struct(req
->task
);
1380 io_req_work_drop_env(req
);
1383 static void __io_free_req(struct io_kiocb
*req
)
1385 __io_req_aux_free(req
);
1387 if (req
->flags
& REQ_F_INFLIGHT
) {
1388 struct io_ring_ctx
*ctx
= req
->ctx
;
1389 unsigned long flags
;
1391 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1392 list_del(&req
->inflight_entry
);
1393 if (waitqueue_active(&ctx
->inflight_wait
))
1394 wake_up(&ctx
->inflight_wait
);
1395 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1398 percpu_ref_put(&req
->ctx
->refs
);
1399 if (likely(!io_is_fallback_req(req
)))
1400 kmem_cache_free(req_cachep
, req
);
1402 clear_bit_unlock(0, (unsigned long *) &req
->ctx
->fallback_req
);
1406 void *reqs
[IO_IOPOLL_BATCH
];
1411 static void io_free_req_many(struct io_ring_ctx
*ctx
, struct req_batch
*rb
)
1415 if (rb
->need_iter
) {
1416 int i
, inflight
= 0;
1417 unsigned long flags
;
1419 for (i
= 0; i
< rb
->to_free
; i
++) {
1420 struct io_kiocb
*req
= rb
->reqs
[i
];
1422 if (req
->flags
& REQ_F_INFLIGHT
)
1424 __io_req_aux_free(req
);
1429 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1430 for (i
= 0; i
< rb
->to_free
; i
++) {
1431 struct io_kiocb
*req
= rb
->reqs
[i
];
1433 if (req
->flags
& REQ_F_INFLIGHT
) {
1434 list_del(&req
->inflight_entry
);
1439 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1441 if (waitqueue_active(&ctx
->inflight_wait
))
1442 wake_up(&ctx
->inflight_wait
);
1445 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
1446 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
1447 rb
->to_free
= rb
->need_iter
= 0;
1450 static bool io_link_cancel_timeout(struct io_kiocb
*req
)
1452 struct io_ring_ctx
*ctx
= req
->ctx
;
1455 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1457 io_cqring_fill_event(req
, -ECANCELED
);
1458 io_commit_cqring(ctx
);
1459 req
->flags
&= ~REQ_F_LINK_HEAD
;
1467 static void io_req_link_next(struct io_kiocb
*req
, struct io_kiocb
**nxtptr
)
1469 struct io_ring_ctx
*ctx
= req
->ctx
;
1470 bool wake_ev
= false;
1472 /* Already got next link */
1473 if (req
->flags
& REQ_F_LINK_NEXT
)
1477 * The list should never be empty when we are called here. But could
1478 * potentially happen if the chain is messed up, check to be on the
1481 while (!list_empty(&req
->link_list
)) {
1482 struct io_kiocb
*nxt
= list_first_entry(&req
->link_list
,
1483 struct io_kiocb
, link_list
);
1485 if (unlikely((req
->flags
& REQ_F_LINK_TIMEOUT
) &&
1486 (nxt
->flags
& REQ_F_TIMEOUT
))) {
1487 list_del_init(&nxt
->link_list
);
1488 wake_ev
|= io_link_cancel_timeout(nxt
);
1489 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1493 list_del_init(&req
->link_list
);
1494 if (!list_empty(&nxt
->link_list
))
1495 nxt
->flags
|= REQ_F_LINK_HEAD
;
1500 req
->flags
|= REQ_F_LINK_NEXT
;
1502 io_cqring_ev_posted(ctx
);
1506 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
1508 static void io_fail_links(struct io_kiocb
*req
)
1510 struct io_ring_ctx
*ctx
= req
->ctx
;
1511 unsigned long flags
;
1513 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1515 while (!list_empty(&req
->link_list
)) {
1516 struct io_kiocb
*link
= list_first_entry(&req
->link_list
,
1517 struct io_kiocb
, link_list
);
1519 list_del_init(&link
->link_list
);
1520 trace_io_uring_fail_link(req
, link
);
1522 if ((req
->flags
& REQ_F_LINK_TIMEOUT
) &&
1523 link
->opcode
== IORING_OP_LINK_TIMEOUT
) {
1524 io_link_cancel_timeout(link
);
1526 io_cqring_fill_event(link
, -ECANCELED
);
1527 __io_double_put_req(link
);
1529 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1532 io_commit_cqring(ctx
);
1533 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1534 io_cqring_ev_posted(ctx
);
1537 static void io_req_find_next(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
1539 if (likely(!(req
->flags
& REQ_F_LINK_HEAD
)))
1543 * If LINK is set, we have dependent requests in this chain. If we
1544 * didn't fail this request, queue the first one up, moving any other
1545 * dependencies to the next request. In case of failure, fail the rest
1548 if (req
->flags
& REQ_F_FAIL_LINK
) {
1550 } else if ((req
->flags
& (REQ_F_LINK_TIMEOUT
| REQ_F_COMP_LOCKED
)) ==
1551 REQ_F_LINK_TIMEOUT
) {
1552 struct io_ring_ctx
*ctx
= req
->ctx
;
1553 unsigned long flags
;
1556 * If this is a timeout link, we could be racing with the
1557 * timeout timer. Grab the completion lock for this case to
1558 * protect against that.
1560 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1561 io_req_link_next(req
, nxt
);
1562 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1564 io_req_link_next(req
, nxt
);
1568 static void io_free_req(struct io_kiocb
*req
)
1570 struct io_kiocb
*nxt
= NULL
;
1572 io_req_find_next(req
, &nxt
);
1576 io_queue_async_work(nxt
);
1579 static void io_link_work_cb(struct io_wq_work
**workptr
)
1581 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
1582 struct io_kiocb
*link
;
1584 link
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1585 io_queue_linked_timeout(link
);
1586 io_wq_submit_work(workptr
);
1589 static void io_wq_assign_next(struct io_wq_work
**workptr
, struct io_kiocb
*nxt
)
1591 struct io_kiocb
*link
;
1592 const struct io_op_def
*def
= &io_op_defs
[nxt
->opcode
];
1594 if ((nxt
->flags
& REQ_F_ISREG
) && def
->hash_reg_file
)
1595 io_wq_hash_work(&nxt
->work
, file_inode(nxt
->file
));
1597 *workptr
= &nxt
->work
;
1598 link
= io_prep_linked_timeout(nxt
);
1600 nxt
->work
.func
= io_link_work_cb
;
1604 * Drop reference to request, return next in chain (if there is one) if this
1605 * was the last reference to this request.
1607 __attribute__((nonnull
))
1608 static void io_put_req_find_next(struct io_kiocb
*req
, struct io_kiocb
**nxtptr
)
1610 if (refcount_dec_and_test(&req
->refs
)) {
1611 io_req_find_next(req
, nxtptr
);
1616 static void io_put_req(struct io_kiocb
*req
)
1618 if (refcount_dec_and_test(&req
->refs
))
1622 static void io_steal_work(struct io_kiocb
*req
,
1623 struct io_wq_work
**workptr
)
1626 * It's in an io-wq worker, so there always should be at least
1627 * one reference, which will be dropped in io_put_work() just
1628 * after the current handler returns.
1630 * It also means, that if the counter dropped to 1, then there is
1631 * no asynchronous users left, so it's safe to steal the next work.
1633 if (refcount_read(&req
->refs
) == 1) {
1634 struct io_kiocb
*nxt
= NULL
;
1636 io_req_find_next(req
, &nxt
);
1638 io_wq_assign_next(workptr
, nxt
);
1643 * Must only be used if we don't need to care about links, usually from
1644 * within the completion handling itself.
1646 static void __io_double_put_req(struct io_kiocb
*req
)
1648 /* drop both submit and complete references */
1649 if (refcount_sub_and_test(2, &req
->refs
))
1653 static void io_double_put_req(struct io_kiocb
*req
)
1655 /* drop both submit and complete references */
1656 if (refcount_sub_and_test(2, &req
->refs
))
1660 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
1662 struct io_rings
*rings
= ctx
->rings
;
1664 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1666 * noflush == true is from the waitqueue handler, just ensure
1667 * we wake up the task, and the next invocation will flush the
1668 * entries. We cannot safely to it from here.
1670 if (noflush
&& !list_empty(&ctx
->cq_overflow_list
))
1673 io_cqring_overflow_flush(ctx
, false);
1676 /* See comment at the top of this file */
1678 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
1681 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
1683 struct io_rings
*rings
= ctx
->rings
;
1685 /* make sure SQ entry isn't read before tail */
1686 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
1689 static inline bool io_req_multi_free(struct req_batch
*rb
, struct io_kiocb
*req
)
1691 if ((req
->flags
& REQ_F_LINK_HEAD
) || io_is_fallback_req(req
))
1694 if (req
->file
|| req
->io
)
1697 rb
->reqs
[rb
->to_free
++] = req
;
1698 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
1699 io_free_req_many(req
->ctx
, rb
);
1703 static int io_put_kbuf(struct io_kiocb
*req
)
1705 struct io_buffer
*kbuf
;
1708 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
1709 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
1710 cflags
|= IORING_CQE_F_BUFFER
;
1717 * Find and free completed poll iocbs
1719 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1720 struct list_head
*done
)
1722 struct req_batch rb
;
1723 struct io_kiocb
*req
;
1725 rb
.to_free
= rb
.need_iter
= 0;
1726 while (!list_empty(done
)) {
1729 req
= list_first_entry(done
, struct io_kiocb
, list
);
1730 list_del(&req
->list
);
1732 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
1733 cflags
= io_put_kbuf(req
);
1735 __io_cqring_fill_event(req
, req
->result
, cflags
);
1738 if (refcount_dec_and_test(&req
->refs
) &&
1739 !io_req_multi_free(&rb
, req
))
1743 io_commit_cqring(ctx
);
1744 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
1745 io_cqring_ev_posted(ctx
);
1746 io_free_req_many(ctx
, &rb
);
1749 static void io_iopoll_queue(struct list_head
*again
)
1751 struct io_kiocb
*req
;
1754 req
= list_first_entry(again
, struct io_kiocb
, list
);
1755 list_del(&req
->list
);
1756 refcount_inc(&req
->refs
);
1757 io_queue_async_work(req
);
1758 } while (!list_empty(again
));
1761 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1764 struct io_kiocb
*req
, *tmp
;
1771 * Only spin for completions if we don't have multiple devices hanging
1772 * off our complete list, and we're under the requested amount.
1774 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
1777 list_for_each_entry_safe(req
, tmp
, &ctx
->poll_list
, list
) {
1778 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
1781 * Move completed and retryable entries to our local lists.
1782 * If we find a request that requires polling, break out
1783 * and complete those lists first, if we have entries there.
1785 if (req
->flags
& REQ_F_IOPOLL_COMPLETED
) {
1786 list_move_tail(&req
->list
, &done
);
1789 if (!list_empty(&done
))
1792 if (req
->result
== -EAGAIN
) {
1793 list_move_tail(&req
->list
, &again
);
1796 if (!list_empty(&again
))
1799 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
1808 if (!list_empty(&done
))
1809 io_iopoll_complete(ctx
, nr_events
, &done
);
1811 if (!list_empty(&again
))
1812 io_iopoll_queue(&again
);
1818 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
1819 * non-spinning poll check - we'll still enter the driver poll loop, but only
1820 * as a non-spinning completion check.
1822 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1825 while (!list_empty(&ctx
->poll_list
) && !need_resched()) {
1828 ret
= io_do_iopoll(ctx
, nr_events
, min
);
1831 if (!min
|| *nr_events
>= min
)
1839 * We can't just wait for polled events to come to us, we have to actively
1840 * find and complete them.
1842 static void io_iopoll_reap_events(struct io_ring_ctx
*ctx
)
1844 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
1847 mutex_lock(&ctx
->uring_lock
);
1848 while (!list_empty(&ctx
->poll_list
)) {
1849 unsigned int nr_events
= 0;
1851 io_iopoll_getevents(ctx
, &nr_events
, 1);
1854 * Ensure we allow local-to-the-cpu processing to take place,
1855 * in this case we need to ensure that we reap all events.
1859 mutex_unlock(&ctx
->uring_lock
);
1862 static int io_iopoll_check(struct io_ring_ctx
*ctx
, unsigned *nr_events
,
1865 int iters
= 0, ret
= 0;
1868 * We disallow the app entering submit/complete with polling, but we
1869 * still need to lock the ring to prevent racing with polled issue
1870 * that got punted to a workqueue.
1872 mutex_lock(&ctx
->uring_lock
);
1877 * Don't enter poll loop if we already have events pending.
1878 * If we do, we can potentially be spinning for commands that
1879 * already triggered a CQE (eg in error).
1881 if (io_cqring_events(ctx
, false))
1885 * If a submit got punted to a workqueue, we can have the
1886 * application entering polling for a command before it gets
1887 * issued. That app will hold the uring_lock for the duration
1888 * of the poll right here, so we need to take a breather every
1889 * now and then to ensure that the issue has a chance to add
1890 * the poll to the issued list. Otherwise we can spin here
1891 * forever, while the workqueue is stuck trying to acquire the
1894 if (!(++iters
& 7)) {
1895 mutex_unlock(&ctx
->uring_lock
);
1896 mutex_lock(&ctx
->uring_lock
);
1899 if (*nr_events
< min
)
1900 tmin
= min
- *nr_events
;
1902 ret
= io_iopoll_getevents(ctx
, nr_events
, tmin
);
1906 } while (min
&& !*nr_events
&& !need_resched());
1908 mutex_unlock(&ctx
->uring_lock
);
1912 static void kiocb_end_write(struct io_kiocb
*req
)
1915 * Tell lockdep we inherited freeze protection from submission
1918 if (req
->flags
& REQ_F_ISREG
) {
1919 struct inode
*inode
= file_inode(req
->file
);
1921 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
1923 file_end_write(req
->file
);
1926 static inline void req_set_fail_links(struct io_kiocb
*req
)
1928 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
1929 req
->flags
|= REQ_F_FAIL_LINK
;
1932 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
)
1934 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
);
1942 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
1943 cflags
= io_put_kbuf(req
);
1944 __io_cqring_add_event(req
, res
, cflags
);
1947 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
1949 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
1951 io_complete_rw_common(kiocb
, res
);
1955 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
1957 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
1959 if (kiocb
->ki_flags
& IOCB_WRITE
)
1960 kiocb_end_write(req
);
1962 if (res
!= req
->result
)
1963 req_set_fail_links(req
);
1966 req
->flags
|= REQ_F_IOPOLL_COMPLETED
;
1970 * After the iocb has been issued, it's safe to be found on the poll list.
1971 * Adding the kiocb to the list AFTER submission ensures that we don't
1972 * find it from a io_iopoll_getevents() thread before the issuer is done
1973 * accessing the kiocb cookie.
1975 static void io_iopoll_req_issued(struct io_kiocb
*req
)
1977 struct io_ring_ctx
*ctx
= req
->ctx
;
1980 * Track whether we have multiple files in our lists. This will impact
1981 * how we do polling eventually, not spinning if we're on potentially
1982 * different devices.
1984 if (list_empty(&ctx
->poll_list
)) {
1985 ctx
->poll_multi_file
= false;
1986 } else if (!ctx
->poll_multi_file
) {
1987 struct io_kiocb
*list_req
;
1989 list_req
= list_first_entry(&ctx
->poll_list
, struct io_kiocb
,
1991 if (list_req
->file
!= req
->file
)
1992 ctx
->poll_multi_file
= true;
1996 * For fast devices, IO may have already completed. If it has, add
1997 * it to the front so we find it first.
1999 if (req
->flags
& REQ_F_IOPOLL_COMPLETED
)
2000 list_add(&req
->list
, &ctx
->poll_list
);
2002 list_add_tail(&req
->list
, &ctx
->poll_list
);
2004 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2005 wq_has_sleeper(&ctx
->sqo_wait
))
2006 wake_up(&ctx
->sqo_wait
);
2009 static void __io_state_file_put(struct io_submit_state
*state
)
2011 int diff
= state
->has_refs
- state
->used_refs
;
2014 fput_many(state
->file
, diff
);
2018 static inline void io_state_file_put(struct io_submit_state
*state
)
2021 __io_state_file_put(state
);
2025 * Get as many references to a file as we have IOs left in this submission,
2026 * assuming most submissions are for one file, or at least that each file
2027 * has more than one submission.
2029 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2035 if (state
->fd
== fd
) {
2040 __io_state_file_put(state
);
2042 state
->file
= fget_many(fd
, state
->ios_left
);
2047 state
->has_refs
= state
->ios_left
;
2048 state
->used_refs
= 1;
2054 * If we tracked the file through the SCM inflight mechanism, we could support
2055 * any file. For now, just ensure that anything potentially problematic is done
2058 static bool io_file_supports_async(struct file
*file
, int rw
)
2060 umode_t mode
= file_inode(file
)->i_mode
;
2062 if (S_ISBLK(mode
) || S_ISCHR(mode
) || S_ISSOCK(mode
))
2064 if (S_ISREG(mode
) && file
->f_op
!= &io_uring_fops
)
2067 if (!(file
->f_mode
& FMODE_NOWAIT
))
2071 return file
->f_op
->read_iter
!= NULL
;
2073 return file
->f_op
->write_iter
!= NULL
;
2076 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2077 bool force_nonblock
)
2079 struct io_ring_ctx
*ctx
= req
->ctx
;
2080 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2084 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2085 req
->flags
|= REQ_F_ISREG
;
2087 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2088 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2089 req
->flags
|= REQ_F_CUR_POS
;
2090 kiocb
->ki_pos
= req
->file
->f_pos
;
2092 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2093 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2094 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2098 ioprio
= READ_ONCE(sqe
->ioprio
);
2100 ret
= ioprio_check_cap(ioprio
);
2104 kiocb
->ki_ioprio
= ioprio
;
2106 kiocb
->ki_ioprio
= get_current_ioprio();
2108 /* don't allow async punt if RWF_NOWAIT was requested */
2109 if ((kiocb
->ki_flags
& IOCB_NOWAIT
) ||
2110 (req
->file
->f_flags
& O_NONBLOCK
))
2111 req
->flags
|= REQ_F_NOWAIT
;
2114 kiocb
->ki_flags
|= IOCB_NOWAIT
;
2116 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2117 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2118 !kiocb
->ki_filp
->f_op
->iopoll
)
2121 kiocb
->ki_flags
|= IOCB_HIPRI
;
2122 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2125 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2127 kiocb
->ki_complete
= io_complete_rw
;
2130 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2131 req
->rw
.len
= READ_ONCE(sqe
->len
);
2132 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2136 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2142 case -ERESTARTNOINTR
:
2143 case -ERESTARTNOHAND
:
2144 case -ERESTART_RESTARTBLOCK
:
2146 * We can't just restart the syscall, since previously
2147 * submitted sqes may already be in progress. Just fail this
2153 kiocb
->ki_complete(kiocb
, ret
, 0);
2157 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
)
2159 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2161 if (req
->flags
& REQ_F_CUR_POS
)
2162 req
->file
->f_pos
= kiocb
->ki_pos
;
2163 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2164 io_complete_rw(kiocb
, ret
, 0);
2166 io_rw_done(kiocb
, ret
);
2169 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2170 struct iov_iter
*iter
)
2172 struct io_ring_ctx
*ctx
= req
->ctx
;
2173 size_t len
= req
->rw
.len
;
2174 struct io_mapped_ubuf
*imu
;
2175 u16 index
, buf_index
;
2179 /* attempt to use fixed buffers without having provided iovecs */
2180 if (unlikely(!ctx
->user_bufs
))
2183 buf_index
= req
->buf_index
;
2184 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2187 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2188 imu
= &ctx
->user_bufs
[index
];
2189 buf_addr
= req
->rw
.addr
;
2192 if (buf_addr
+ len
< buf_addr
)
2194 /* not inside the mapped region */
2195 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2199 * May not be a start of buffer, set size appropriately
2200 * and advance us to the beginning.
2202 offset
= buf_addr
- imu
->ubuf
;
2203 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2207 * Don't use iov_iter_advance() here, as it's really slow for
2208 * using the latter parts of a big fixed buffer - it iterates
2209 * over each segment manually. We can cheat a bit here, because
2212 * 1) it's a BVEC iter, we set it up
2213 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2214 * first and last bvec
2216 * So just find our index, and adjust the iterator afterwards.
2217 * If the offset is within the first bvec (or the whole first
2218 * bvec, just use iov_iter_advance(). This makes it easier
2219 * since we can just skip the first segment, which may not
2220 * be PAGE_SIZE aligned.
2222 const struct bio_vec
*bvec
= imu
->bvec
;
2224 if (offset
<= bvec
->bv_len
) {
2225 iov_iter_advance(iter
, offset
);
2227 unsigned long seg_skip
;
2229 /* skip first vec */
2230 offset
-= bvec
->bv_len
;
2231 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2233 iter
->bvec
= bvec
+ seg_skip
;
2234 iter
->nr_segs
-= seg_skip
;
2235 iter
->count
-= bvec
->bv_len
+ offset
;
2236 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2243 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2246 mutex_unlock(&ctx
->uring_lock
);
2249 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2252 * "Normal" inline submissions always hold the uring_lock, since we
2253 * grab it from the system call. Same is true for the SQPOLL offload.
2254 * The only exception is when we've detached the request and issue it
2255 * from an async worker thread, grab the lock for that case.
2258 mutex_lock(&ctx
->uring_lock
);
2261 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2262 int bgid
, struct io_buffer
*kbuf
,
2265 struct io_buffer
*head
;
2267 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2270 io_ring_submit_lock(req
->ctx
, needs_lock
);
2272 lockdep_assert_held(&req
->ctx
->uring_lock
);
2274 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
2276 if (!list_empty(&head
->list
)) {
2277 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2279 list_del(&kbuf
->list
);
2282 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
2284 if (*len
> kbuf
->len
)
2287 kbuf
= ERR_PTR(-ENOBUFS
);
2290 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2295 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2298 struct io_buffer
*kbuf
;
2301 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2302 bgid
= req
->buf_index
;
2303 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2306 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2307 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2308 return u64_to_user_ptr(kbuf
->addr
);
2311 #ifdef CONFIG_COMPAT
2312 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2315 struct compat_iovec __user
*uiov
;
2316 compat_ssize_t clen
;
2320 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2321 if (!access_ok(uiov
, sizeof(*uiov
)))
2323 if (__get_user(clen
, &uiov
->iov_len
))
2329 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2331 return PTR_ERR(buf
);
2332 iov
[0].iov_base
= buf
;
2333 iov
[0].iov_len
= (compat_size_t
) len
;
2338 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2341 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2345 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
2348 len
= iov
[0].iov_len
;
2351 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2353 return PTR_ERR(buf
);
2354 iov
[0].iov_base
= buf
;
2355 iov
[0].iov_len
= len
;
2359 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2362 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2366 else if (req
->rw
.len
> 1)
2369 #ifdef CONFIG_COMPAT
2370 if (req
->ctx
->compat
)
2371 return io_compat_import(req
, iov
, needs_lock
);
2374 return __io_iov_buffer_select(req
, iov
, needs_lock
);
2377 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
2378 struct iovec
**iovec
, struct iov_iter
*iter
,
2381 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
2382 size_t sqe_len
= req
->rw
.len
;
2386 opcode
= req
->opcode
;
2387 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
2389 return io_import_fixed(req
, rw
, iter
);
2392 /* buffer index only valid with fixed read/write, or buffer select */
2393 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
2396 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
2397 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2398 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
2401 return PTR_ERR(buf
);
2403 req
->rw
.len
= sqe_len
;
2406 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
2408 return ret
< 0 ? ret
: sqe_len
;
2412 struct io_async_rw
*iorw
= &req
->io
->rw
;
2415 iov_iter_init(iter
, rw
, *iovec
, iorw
->nr_segs
, iorw
->size
);
2416 if (iorw
->iov
== iorw
->fast_iov
)
2421 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2422 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
2424 ret
= (*iovec
)->iov_len
;
2425 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
2431 #ifdef CONFIG_COMPAT
2432 if (req
->ctx
->compat
)
2433 return compat_import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
,
2437 return import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
);
2441 * For files that don't have ->read_iter() and ->write_iter(), handle them
2442 * by looping over ->read() or ->write() manually.
2444 static ssize_t
loop_rw_iter(int rw
, struct file
*file
, struct kiocb
*kiocb
,
2445 struct iov_iter
*iter
)
2450 * Don't support polled IO through this interface, and we can't
2451 * support non-blocking either. For the latter, this just causes
2452 * the kiocb to be handled from an async context.
2454 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2456 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2459 while (iov_iter_count(iter
)) {
2463 if (!iov_iter_is_bvec(iter
)) {
2464 iovec
= iov_iter_iovec(iter
);
2466 /* fixed buffers import bvec */
2467 iovec
.iov_base
= kmap(iter
->bvec
->bv_page
)
2469 iovec
.iov_len
= min(iter
->count
,
2470 iter
->bvec
->bv_len
- iter
->iov_offset
);
2474 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
2475 iovec
.iov_len
, &kiocb
->ki_pos
);
2477 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
2478 iovec
.iov_len
, &kiocb
->ki_pos
);
2481 if (iov_iter_is_bvec(iter
))
2482 kunmap(iter
->bvec
->bv_page
);
2490 if (nr
!= iovec
.iov_len
)
2492 iov_iter_advance(iter
, nr
);
2498 static void io_req_map_rw(struct io_kiocb
*req
, ssize_t io_size
,
2499 struct iovec
*iovec
, struct iovec
*fast_iov
,
2500 struct iov_iter
*iter
)
2502 req
->io
->rw
.nr_segs
= iter
->nr_segs
;
2503 req
->io
->rw
.size
= io_size
;
2504 req
->io
->rw
.iov
= iovec
;
2505 if (!req
->io
->rw
.iov
) {
2506 req
->io
->rw
.iov
= req
->io
->rw
.fast_iov
;
2507 if (req
->io
->rw
.iov
!= fast_iov
)
2508 memcpy(req
->io
->rw
.iov
, fast_iov
,
2509 sizeof(struct iovec
) * iter
->nr_segs
);
2511 req
->flags
|= REQ_F_NEED_CLEANUP
;
2515 static inline int __io_alloc_async_ctx(struct io_kiocb
*req
)
2517 req
->io
= kmalloc(sizeof(*req
->io
), GFP_KERNEL
);
2518 return req
->io
== NULL
;
2521 static int io_alloc_async_ctx(struct io_kiocb
*req
)
2523 if (!io_op_defs
[req
->opcode
].async_ctx
)
2526 return __io_alloc_async_ctx(req
);
2529 static int io_setup_async_rw(struct io_kiocb
*req
, ssize_t io_size
,
2530 struct iovec
*iovec
, struct iovec
*fast_iov
,
2531 struct iov_iter
*iter
)
2533 if (!io_op_defs
[req
->opcode
].async_ctx
)
2536 if (__io_alloc_async_ctx(req
))
2539 io_req_map_rw(req
, io_size
, iovec
, fast_iov
, iter
);
2544 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2545 bool force_nonblock
)
2547 struct io_async_ctx
*io
;
2548 struct iov_iter iter
;
2551 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
2555 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
2558 /* either don't need iovec imported or already have it */
2559 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
2563 io
->rw
.iov
= io
->rw
.fast_iov
;
2565 ret
= io_import_iovec(READ
, req
, &io
->rw
.iov
, &iter
, !force_nonblock
);
2570 io_req_map_rw(req
, ret
, io
->rw
.iov
, io
->rw
.fast_iov
, &iter
);
2574 static int io_read(struct io_kiocb
*req
, bool force_nonblock
)
2576 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2577 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2578 struct iov_iter iter
;
2580 ssize_t io_size
, ret
;
2582 ret
= io_import_iovec(READ
, req
, &iovec
, &iter
, !force_nonblock
);
2586 /* Ensure we clear previously set non-block flag */
2587 if (!force_nonblock
)
2588 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
2592 if (req
->flags
& REQ_F_LINK_HEAD
)
2593 req
->result
= io_size
;
2596 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
2597 * we know to async punt it even if it was opened O_NONBLOCK
2599 if (force_nonblock
&& !io_file_supports_async(req
->file
, READ
))
2602 iov_count
= iov_iter_count(&iter
);
2603 ret
= rw_verify_area(READ
, req
->file
, &kiocb
->ki_pos
, iov_count
);
2607 if (req
->file
->f_op
->read_iter
)
2608 ret2
= call_read_iter(req
->file
, kiocb
, &iter
);
2610 ret2
= loop_rw_iter(READ
, req
->file
, kiocb
, &iter
);
2612 /* Catch -EAGAIN return for forced non-blocking submission */
2613 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
2614 kiocb_done(kiocb
, ret2
);
2617 ret
= io_setup_async_rw(req
, io_size
, iovec
,
2618 inline_vecs
, &iter
);
2621 /* any defer here is final, must blocking retry */
2622 if (!(req
->flags
& REQ_F_NOWAIT
) &&
2623 !file_can_poll(req
->file
))
2624 req
->flags
|= REQ_F_MUST_PUNT
;
2630 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2634 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2635 bool force_nonblock
)
2637 struct io_async_ctx
*io
;
2638 struct iov_iter iter
;
2641 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
2645 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
2648 req
->fsize
= rlimit(RLIMIT_FSIZE
);
2650 /* either don't need iovec imported or already have it */
2651 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
2655 io
->rw
.iov
= io
->rw
.fast_iov
;
2657 ret
= io_import_iovec(WRITE
, req
, &io
->rw
.iov
, &iter
, !force_nonblock
);
2662 io_req_map_rw(req
, ret
, io
->rw
.iov
, io
->rw
.fast_iov
, &iter
);
2666 static int io_write(struct io_kiocb
*req
, bool force_nonblock
)
2668 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2669 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2670 struct iov_iter iter
;
2672 ssize_t ret
, io_size
;
2674 ret
= io_import_iovec(WRITE
, req
, &iovec
, &iter
, !force_nonblock
);
2678 /* Ensure we clear previously set non-block flag */
2679 if (!force_nonblock
)
2680 req
->rw
.kiocb
.ki_flags
&= ~IOCB_NOWAIT
;
2684 if (req
->flags
& REQ_F_LINK_HEAD
)
2685 req
->result
= io_size
;
2688 * If the file doesn't support async, mark it as REQ_F_MUST_PUNT so
2689 * we know to async punt it even if it was opened O_NONBLOCK
2691 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
2694 /* file path doesn't support NOWAIT for non-direct_IO */
2695 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
2696 (req
->flags
& REQ_F_ISREG
))
2699 iov_count
= iov_iter_count(&iter
);
2700 ret
= rw_verify_area(WRITE
, req
->file
, &kiocb
->ki_pos
, iov_count
);
2705 * Open-code file_start_write here to grab freeze protection,
2706 * which will be released by another thread in
2707 * io_complete_rw(). Fool lockdep by telling it the lock got
2708 * released so that it doesn't complain about the held lock when
2709 * we return to userspace.
2711 if (req
->flags
& REQ_F_ISREG
) {
2712 __sb_start_write(file_inode(req
->file
)->i_sb
,
2713 SB_FREEZE_WRITE
, true);
2714 __sb_writers_release(file_inode(req
->file
)->i_sb
,
2717 kiocb
->ki_flags
|= IOCB_WRITE
;
2719 if (!force_nonblock
)
2720 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= req
->fsize
;
2722 if (req
->file
->f_op
->write_iter
)
2723 ret2
= call_write_iter(req
->file
, kiocb
, &iter
);
2725 ret2
= loop_rw_iter(WRITE
, req
->file
, kiocb
, &iter
);
2727 if (!force_nonblock
)
2728 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= RLIM_INFINITY
;
2731 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
2732 * retry them without IOCB_NOWAIT.
2734 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
2736 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
2737 kiocb_done(kiocb
, ret2
);
2740 ret
= io_setup_async_rw(req
, io_size
, iovec
,
2741 inline_vecs
, &iter
);
2744 /* any defer here is final, must blocking retry */
2745 if (!file_can_poll(req
->file
))
2746 req
->flags
|= REQ_F_MUST_PUNT
;
2751 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2756 static int __io_splice_prep(struct io_kiocb
*req
,
2757 const struct io_uring_sqe
*sqe
)
2759 struct io_splice
* sp
= &req
->splice
;
2760 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
2763 if (req
->flags
& REQ_F_NEED_CLEANUP
)
2767 sp
->len
= READ_ONCE(sqe
->len
);
2768 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
2770 if (unlikely(sp
->flags
& ~valid_flags
))
2773 ret
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
), &sp
->file_in
,
2774 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
2777 req
->flags
|= REQ_F_NEED_CLEANUP
;
2779 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
))
2780 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
2785 static int io_tee_prep(struct io_kiocb
*req
,
2786 const struct io_uring_sqe
*sqe
)
2788 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
2790 return __io_splice_prep(req
, sqe
);
2793 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
2795 struct io_splice
*sp
= &req
->splice
;
2796 struct file
*in
= sp
->file_in
;
2797 struct file
*out
= sp
->file_out
;
2798 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
2804 ret
= do_tee(in
, out
, sp
->len
, flags
);
2806 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
2807 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2809 io_cqring_add_event(req
, ret
);
2811 req_set_fail_links(req
);
2816 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2818 struct io_splice
* sp
= &req
->splice
;
2820 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
2821 sp
->off_out
= READ_ONCE(sqe
->off
);
2822 return __io_splice_prep(req
, sqe
);
2825 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
2827 struct io_splice
*sp
= &req
->splice
;
2828 struct file
*in
= sp
->file_in
;
2829 struct file
*out
= sp
->file_out
;
2830 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
2831 loff_t
*poff_in
, *poff_out
;
2837 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
2838 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
2841 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
2843 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
2844 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
2846 io_cqring_add_event(req
, ret
);
2848 req_set_fail_links(req
);
2854 * IORING_OP_NOP just posts a completion event, nothing else.
2856 static int io_nop(struct io_kiocb
*req
)
2858 struct io_ring_ctx
*ctx
= req
->ctx
;
2860 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
2863 io_cqring_add_event(req
, 0);
2868 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2870 struct io_ring_ctx
*ctx
= req
->ctx
;
2875 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
2877 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
2880 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
2881 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
2884 req
->sync
.off
= READ_ONCE(sqe
->off
);
2885 req
->sync
.len
= READ_ONCE(sqe
->len
);
2889 static bool io_req_cancelled(struct io_kiocb
*req
)
2891 if (req
->work
.flags
& IO_WQ_WORK_CANCEL
) {
2892 req_set_fail_links(req
);
2893 io_cqring_add_event(req
, -ECANCELED
);
2901 static void __io_fsync(struct io_kiocb
*req
)
2903 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
2906 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
2907 end
> 0 ? end
: LLONG_MAX
,
2908 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
2910 req_set_fail_links(req
);
2911 io_cqring_add_event(req
, ret
);
2915 static void io_fsync_finish(struct io_wq_work
**workptr
)
2917 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
2919 if (io_req_cancelled(req
))
2922 io_steal_work(req
, workptr
);
2925 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
2927 /* fsync always requires a blocking context */
2928 if (force_nonblock
) {
2929 req
->work
.func
= io_fsync_finish
;
2936 static void __io_fallocate(struct io_kiocb
*req
)
2940 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= req
->fsize
;
2941 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
2943 current
->signal
->rlim
[RLIMIT_FSIZE
].rlim_cur
= RLIM_INFINITY
;
2945 req_set_fail_links(req
);
2946 io_cqring_add_event(req
, ret
);
2950 static void io_fallocate_finish(struct io_wq_work
**workptr
)
2952 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
2954 if (io_req_cancelled(req
))
2956 __io_fallocate(req
);
2957 io_steal_work(req
, workptr
);
2960 static int io_fallocate_prep(struct io_kiocb
*req
,
2961 const struct io_uring_sqe
*sqe
)
2963 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
2966 req
->sync
.off
= READ_ONCE(sqe
->off
);
2967 req
->sync
.len
= READ_ONCE(sqe
->addr
);
2968 req
->sync
.mode
= READ_ONCE(sqe
->len
);
2969 req
->fsize
= rlimit(RLIMIT_FSIZE
);
2973 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
2975 /* fallocate always requiring blocking context */
2976 if (force_nonblock
) {
2977 req
->work
.func
= io_fallocate_finish
;
2981 __io_fallocate(req
);
2985 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
2987 const char __user
*fname
;
2990 if (sqe
->ioprio
|| sqe
->buf_index
)
2992 if (req
->flags
& REQ_F_FIXED_FILE
)
2994 if (req
->flags
& REQ_F_NEED_CLEANUP
)
2997 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
2998 req
->open
.how
.mode
= READ_ONCE(sqe
->len
);
2999 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3000 req
->open
.how
.flags
= READ_ONCE(sqe
->open_flags
);
3001 if (force_o_largefile())
3002 req
->open
.how
.flags
|= O_LARGEFILE
;
3004 req
->open
.filename
= getname(fname
);
3005 if (IS_ERR(req
->open
.filename
)) {
3006 ret
= PTR_ERR(req
->open
.filename
);
3007 req
->open
.filename
= NULL
;
3011 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3012 req
->flags
|= REQ_F_NEED_CLEANUP
;
3016 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3018 struct open_how __user
*how
;
3019 const char __user
*fname
;
3023 if (sqe
->ioprio
|| sqe
->buf_index
)
3025 if (req
->flags
& REQ_F_FIXED_FILE
)
3027 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3030 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3031 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3032 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3033 len
= READ_ONCE(sqe
->len
);
3035 if (len
< OPEN_HOW_SIZE_VER0
)
3038 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3043 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3044 req
->open
.how
.flags
|= O_LARGEFILE
;
3046 req
->open
.filename
= getname(fname
);
3047 if (IS_ERR(req
->open
.filename
)) {
3048 ret
= PTR_ERR(req
->open
.filename
);
3049 req
->open
.filename
= NULL
;
3053 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3054 req
->flags
|= REQ_F_NEED_CLEANUP
;
3058 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
3060 struct open_flags op
;
3067 ret
= build_open_flags(&req
->open
.how
, &op
);
3071 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3075 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3078 ret
= PTR_ERR(file
);
3080 fsnotify_open(file
);
3081 fd_install(ret
, file
);
3084 putname(req
->open
.filename
);
3085 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3087 req_set_fail_links(req
);
3088 io_cqring_add_event(req
, ret
);
3093 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
3095 req
->open
.how
= build_open_how(req
->open
.how
.flags
, req
->open
.how
.mode
);
3096 return io_openat2(req
, force_nonblock
);
3099 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3100 const struct io_uring_sqe
*sqe
)
3102 struct io_provide_buf
*p
= &req
->pbuf
;
3105 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3108 tmp
= READ_ONCE(sqe
->fd
);
3109 if (!tmp
|| tmp
> USHRT_MAX
)
3112 memset(p
, 0, sizeof(*p
));
3114 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3118 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3119 int bgid
, unsigned nbufs
)
3123 /* shouldn't happen */
3127 /* the head kbuf is the list itself */
3128 while (!list_empty(&buf
->list
)) {
3129 struct io_buffer
*nxt
;
3131 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3132 list_del(&nxt
->list
);
3139 idr_remove(&ctx
->io_buffer_idr
, bgid
);
3144 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
)
3146 struct io_provide_buf
*p
= &req
->pbuf
;
3147 struct io_ring_ctx
*ctx
= req
->ctx
;
3148 struct io_buffer
*head
;
3151 io_ring_submit_lock(ctx
, !force_nonblock
);
3153 lockdep_assert_held(&ctx
->uring_lock
);
3156 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3158 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3160 io_ring_submit_lock(ctx
, !force_nonblock
);
3162 req_set_fail_links(req
);
3163 io_cqring_add_event(req
, ret
);
3168 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3169 const struct io_uring_sqe
*sqe
)
3171 struct io_provide_buf
*p
= &req
->pbuf
;
3174 if (sqe
->ioprio
|| sqe
->rw_flags
)
3177 tmp
= READ_ONCE(sqe
->fd
);
3178 if (!tmp
|| tmp
> USHRT_MAX
)
3181 p
->addr
= READ_ONCE(sqe
->addr
);
3182 p
->len
= READ_ONCE(sqe
->len
);
3184 if (!access_ok(u64_to_user_ptr(p
->addr
), p
->len
))
3187 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3188 tmp
= READ_ONCE(sqe
->off
);
3189 if (tmp
> USHRT_MAX
)
3195 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3197 struct io_buffer
*buf
;
3198 u64 addr
= pbuf
->addr
;
3199 int i
, bid
= pbuf
->bid
;
3201 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3202 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3207 buf
->len
= pbuf
->len
;
3212 INIT_LIST_HEAD(&buf
->list
);
3215 list_add_tail(&buf
->list
, &(*head
)->list
);
3219 return i
? i
: -ENOMEM
;
3222 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
)
3224 struct io_provide_buf
*p
= &req
->pbuf
;
3225 struct io_ring_ctx
*ctx
= req
->ctx
;
3226 struct io_buffer
*head
, *list
;
3229 io_ring_submit_lock(ctx
, !force_nonblock
);
3231 lockdep_assert_held(&ctx
->uring_lock
);
3233 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3235 ret
= io_add_buffers(p
, &head
);
3240 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
3243 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
3248 io_ring_submit_unlock(ctx
, !force_nonblock
);
3250 req_set_fail_links(req
);
3251 io_cqring_add_event(req
, ret
);
3256 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
3257 const struct io_uring_sqe
*sqe
)
3259 #if defined(CONFIG_EPOLL)
3260 if (sqe
->ioprio
|| sqe
->buf_index
)
3263 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
3264 req
->epoll
.op
= READ_ONCE(sqe
->len
);
3265 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
3267 if (ep_op_has_event(req
->epoll
.op
)) {
3268 struct epoll_event __user
*ev
;
3270 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3271 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
3281 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
)
3283 #if defined(CONFIG_EPOLL)
3284 struct io_epoll
*ie
= &req
->epoll
;
3287 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
3288 if (force_nonblock
&& ret
== -EAGAIN
)
3292 req_set_fail_links(req
);
3293 io_cqring_add_event(req
, ret
);
3301 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3303 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3304 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
3307 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
3308 req
->madvise
.len
= READ_ONCE(sqe
->len
);
3309 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3316 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
3318 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3319 struct io_madvise
*ma
= &req
->madvise
;
3325 ret
= do_madvise(ma
->addr
, ma
->len
, ma
->advice
);
3327 req_set_fail_links(req
);
3328 io_cqring_add_event(req
, ret
);
3336 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3338 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
3341 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
3342 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
3343 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3347 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
3349 struct io_fadvise
*fa
= &req
->fadvise
;
3352 if (force_nonblock
) {
3353 switch (fa
->advice
) {
3354 case POSIX_FADV_NORMAL
:
3355 case POSIX_FADV_RANDOM
:
3356 case POSIX_FADV_SEQUENTIAL
:
3363 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
3365 req_set_fail_links(req
);
3366 io_cqring_add_event(req
, ret
);
3371 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3373 if (sqe
->ioprio
|| sqe
->buf_index
)
3375 if (req
->flags
& REQ_F_FIXED_FILE
)
3378 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
3379 req
->statx
.mask
= READ_ONCE(sqe
->len
);
3380 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3381 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3382 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
3387 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
3389 struct io_statx
*ctx
= &req
->statx
;
3392 if (force_nonblock
) {
3393 /* only need file table for an actual valid fd */
3394 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
3395 req
->flags
|= REQ_F_NO_FILE_TABLE
;
3399 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
3403 req_set_fail_links(req
);
3404 io_cqring_add_event(req
, ret
);
3409 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3412 * If we queue this for async, it must not be cancellable. That would
3413 * leave the 'file' in an undeterminate state.
3415 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
3417 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
3418 sqe
->rw_flags
|| sqe
->buf_index
)
3420 if (req
->flags
& REQ_F_FIXED_FILE
)
3423 req
->close
.fd
= READ_ONCE(sqe
->fd
);
3427 /* only called when __close_fd_get_file() is done */
3428 static void __io_close_finish(struct io_kiocb
*req
)
3432 ret
= filp_close(req
->close
.put_file
, req
->work
.files
);
3434 req_set_fail_links(req
);
3435 io_cqring_add_event(req
, ret
);
3436 fput(req
->close
.put_file
);
3440 static void io_close_finish(struct io_wq_work
**workptr
)
3442 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3444 /* not cancellable, don't do io_req_cancelled() */
3445 __io_close_finish(req
);
3446 io_steal_work(req
, workptr
);
3449 static int io_close(struct io_kiocb
*req
, bool force_nonblock
)
3453 req
->close
.put_file
= NULL
;
3454 ret
= __close_fd_get_file(req
->close
.fd
, &req
->close
.put_file
);
3456 return (ret
== -ENOENT
) ? -EBADF
: ret
;
3458 /* if the file has a flush method, be safe and punt to async */
3459 if (req
->close
.put_file
->f_op
->flush
&& force_nonblock
) {
3460 /* avoid grabbing files - we don't need the files */
3461 req
->flags
|= REQ_F_NO_FILE_TABLE
| REQ_F_MUST_PUNT
;
3462 req
->work
.func
= io_close_finish
;
3467 * No ->flush(), safely close from here and just punt the
3468 * fput() to async context.
3470 __io_close_finish(req
);
3474 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3476 struct io_ring_ctx
*ctx
= req
->ctx
;
3481 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3483 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3486 req
->sync
.off
= READ_ONCE(sqe
->off
);
3487 req
->sync
.len
= READ_ONCE(sqe
->len
);
3488 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
3492 static void __io_sync_file_range(struct io_kiocb
*req
)
3496 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
3499 req_set_fail_links(req
);
3500 io_cqring_add_event(req
, ret
);
3505 static void io_sync_file_range_finish(struct io_wq_work
**workptr
)
3507 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3509 if (io_req_cancelled(req
))
3511 __io_sync_file_range(req
);
3512 io_steal_work(req
, workptr
);
3515 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
3517 /* sync_file_range always requires a blocking context */
3518 if (force_nonblock
) {
3519 req
->work
.func
= io_sync_file_range_finish
;
3523 __io_sync_file_range(req
);
3527 #if defined(CONFIG_NET)
3528 static int io_setup_async_msg(struct io_kiocb
*req
,
3529 struct io_async_msghdr
*kmsg
)
3533 if (io_alloc_async_ctx(req
)) {
3534 if (kmsg
->iov
!= kmsg
->fast_iov
)
3538 req
->flags
|= REQ_F_NEED_CLEANUP
;
3539 memcpy(&req
->io
->msg
, kmsg
, sizeof(*kmsg
));
3543 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3545 struct io_sr_msg
*sr
= &req
->sr_msg
;
3546 struct io_async_ctx
*io
= req
->io
;
3549 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
3550 sr
->msg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3551 sr
->len
= READ_ONCE(sqe
->len
);
3553 #ifdef CONFIG_COMPAT
3554 if (req
->ctx
->compat
)
3555 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
3558 if (!io
|| req
->opcode
== IORING_OP_SEND
)
3560 /* iovec is already imported */
3561 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3564 io
->msg
.iov
= io
->msg
.fast_iov
;
3565 ret
= sendmsg_copy_msghdr(&io
->msg
.msg
, sr
->msg
, sr
->msg_flags
,
3568 req
->flags
|= REQ_F_NEED_CLEANUP
;
3572 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
)
3574 struct io_async_msghdr
*kmsg
= NULL
;
3575 struct socket
*sock
;
3578 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3581 sock
= sock_from_file(req
->file
, &ret
);
3583 struct io_async_ctx io
;
3587 kmsg
= &req
->io
->msg
;
3588 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
3589 /* if iov is set, it's allocated already */
3591 kmsg
->iov
= kmsg
->fast_iov
;
3592 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
3594 struct io_sr_msg
*sr
= &req
->sr_msg
;
3597 kmsg
->msg
.msg_name
= &io
.msg
.addr
;
3599 io
.msg
.iov
= io
.msg
.fast_iov
;
3600 ret
= sendmsg_copy_msghdr(&io
.msg
.msg
, sr
->msg
,
3601 sr
->msg_flags
, &io
.msg
.iov
);
3606 flags
= req
->sr_msg
.msg_flags
;
3607 if (flags
& MSG_DONTWAIT
)
3608 req
->flags
|= REQ_F_NOWAIT
;
3609 else if (force_nonblock
)
3610 flags
|= MSG_DONTWAIT
;
3612 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
3613 if (force_nonblock
&& ret
== -EAGAIN
)
3614 return io_setup_async_msg(req
, kmsg
);
3615 if (ret
== -ERESTARTSYS
)
3619 if (kmsg
&& kmsg
->iov
!= kmsg
->fast_iov
)
3621 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3622 io_cqring_add_event(req
, ret
);
3624 req_set_fail_links(req
);
3629 static int io_send(struct io_kiocb
*req
, bool force_nonblock
)
3631 struct socket
*sock
;
3634 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3637 sock
= sock_from_file(req
->file
, &ret
);
3639 struct io_sr_msg
*sr
= &req
->sr_msg
;
3644 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
,
3649 msg
.msg_name
= NULL
;
3650 msg
.msg_control
= NULL
;
3651 msg
.msg_controllen
= 0;
3652 msg
.msg_namelen
= 0;
3654 flags
= req
->sr_msg
.msg_flags
;
3655 if (flags
& MSG_DONTWAIT
)
3656 req
->flags
|= REQ_F_NOWAIT
;
3657 else if (force_nonblock
)
3658 flags
|= MSG_DONTWAIT
;
3660 msg
.msg_flags
= flags
;
3661 ret
= sock_sendmsg(sock
, &msg
);
3662 if (force_nonblock
&& ret
== -EAGAIN
)
3664 if (ret
== -ERESTARTSYS
)
3668 io_cqring_add_event(req
, ret
);
3670 req_set_fail_links(req
);
3675 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
, struct io_async_ctx
*io
)
3677 struct io_sr_msg
*sr
= &req
->sr_msg
;
3678 struct iovec __user
*uiov
;
3682 ret
= __copy_msghdr_from_user(&io
->msg
.msg
, sr
->msg
, &io
->msg
.uaddr
,
3687 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3690 if (copy_from_user(io
->msg
.iov
, uiov
, sizeof(*uiov
)))
3692 sr
->len
= io
->msg
.iov
[0].iov_len
;
3693 iov_iter_init(&io
->msg
.msg
.msg_iter
, READ
, io
->msg
.iov
, 1,
3697 ret
= import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
3698 &io
->msg
.iov
, &io
->msg
.msg
.msg_iter
);
3706 #ifdef CONFIG_COMPAT
3707 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
3708 struct io_async_ctx
*io
)
3710 struct compat_msghdr __user
*msg_compat
;
3711 struct io_sr_msg
*sr
= &req
->sr_msg
;
3712 struct compat_iovec __user
*uiov
;
3717 msg_compat
= (struct compat_msghdr __user
*) sr
->msg
;
3718 ret
= __get_compat_msghdr(&io
->msg
.msg
, msg_compat
, &io
->msg
.uaddr
,
3723 uiov
= compat_ptr(ptr
);
3724 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
3725 compat_ssize_t clen
;
3729 if (!access_ok(uiov
, sizeof(*uiov
)))
3731 if (__get_user(clen
, &uiov
->iov_len
))
3735 sr
->len
= io
->msg
.iov
[0].iov_len
;
3738 ret
= compat_import_iovec(READ
, uiov
, len
, UIO_FASTIOV
,
3740 &io
->msg
.msg
.msg_iter
);
3749 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
, struct io_async_ctx
*io
)
3751 io
->msg
.iov
= io
->msg
.fast_iov
;
3753 #ifdef CONFIG_COMPAT
3754 if (req
->ctx
->compat
)
3755 return __io_compat_recvmsg_copy_hdr(req
, io
);
3758 return __io_recvmsg_copy_hdr(req
, io
);
3761 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
3762 int *cflags
, bool needs_lock
)
3764 struct io_sr_msg
*sr
= &req
->sr_msg
;
3765 struct io_buffer
*kbuf
;
3767 if (!(req
->flags
& REQ_F_BUFFER_SELECT
))
3770 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
3775 req
->flags
|= REQ_F_BUFFER_SELECTED
;
3777 *cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
3778 *cflags
|= IORING_CQE_F_BUFFER
;
3782 static int io_recvmsg_prep(struct io_kiocb
*req
,
3783 const struct io_uring_sqe
*sqe
)
3785 struct io_sr_msg
*sr
= &req
->sr_msg
;
3786 struct io_async_ctx
*io
= req
->io
;
3789 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
3790 sr
->msg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3791 sr
->len
= READ_ONCE(sqe
->len
);
3792 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
3794 #ifdef CONFIG_COMPAT
3795 if (req
->ctx
->compat
)
3796 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
3799 if (!io
|| req
->opcode
== IORING_OP_RECV
)
3801 /* iovec is already imported */
3802 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3805 ret
= io_recvmsg_copy_hdr(req
, io
);
3807 req
->flags
|= REQ_F_NEED_CLEANUP
;
3811 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
)
3813 struct io_async_msghdr
*kmsg
= NULL
;
3814 struct socket
*sock
;
3815 int ret
, cflags
= 0;
3817 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3820 sock
= sock_from_file(req
->file
, &ret
);
3822 struct io_buffer
*kbuf
;
3823 struct io_async_ctx io
;
3827 kmsg
= &req
->io
->msg
;
3828 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
3829 /* if iov is set, it's allocated already */
3831 kmsg
->iov
= kmsg
->fast_iov
;
3832 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
3835 kmsg
->msg
.msg_name
= &io
.msg
.addr
;
3837 ret
= io_recvmsg_copy_hdr(req
, &io
);
3842 kbuf
= io_recv_buffer_select(req
, &cflags
, !force_nonblock
);
3844 return PTR_ERR(kbuf
);
3846 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
3847 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
3848 1, req
->sr_msg
.len
);
3851 flags
= req
->sr_msg
.msg_flags
;
3852 if (flags
& MSG_DONTWAIT
)
3853 req
->flags
|= REQ_F_NOWAIT
;
3854 else if (force_nonblock
)
3855 flags
|= MSG_DONTWAIT
;
3857 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.msg
,
3858 kmsg
->uaddr
, flags
);
3859 if (force_nonblock
&& ret
== -EAGAIN
)
3860 return io_setup_async_msg(req
, kmsg
);
3861 if (ret
== -ERESTARTSYS
)
3865 if (kmsg
&& kmsg
->iov
!= kmsg
->fast_iov
)
3867 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3868 __io_cqring_add_event(req
, ret
, cflags
);
3870 req_set_fail_links(req
);
3875 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
)
3877 struct io_buffer
*kbuf
= NULL
;
3878 struct socket
*sock
;
3879 int ret
, cflags
= 0;
3881 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3884 sock
= sock_from_file(req
->file
, &ret
);
3886 struct io_sr_msg
*sr
= &req
->sr_msg
;
3887 void __user
*buf
= sr
->buf
;
3892 kbuf
= io_recv_buffer_select(req
, &cflags
, !force_nonblock
);
3894 return PTR_ERR(kbuf
);
3896 buf
= u64_to_user_ptr(kbuf
->addr
);
3898 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
,
3905 req
->flags
|= REQ_F_NEED_CLEANUP
;
3906 msg
.msg_name
= NULL
;
3907 msg
.msg_control
= NULL
;
3908 msg
.msg_controllen
= 0;
3909 msg
.msg_namelen
= 0;
3910 msg
.msg_iocb
= NULL
;
3913 flags
= req
->sr_msg
.msg_flags
;
3914 if (flags
& MSG_DONTWAIT
)
3915 req
->flags
|= REQ_F_NOWAIT
;
3916 else if (force_nonblock
)
3917 flags
|= MSG_DONTWAIT
;
3919 ret
= sock_recvmsg(sock
, &msg
, flags
);
3920 if (force_nonblock
&& ret
== -EAGAIN
)
3922 if (ret
== -ERESTARTSYS
)
3927 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3928 __io_cqring_add_event(req
, ret
, cflags
);
3930 req_set_fail_links(req
);
3935 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3937 struct io_accept
*accept
= &req
->accept
;
3939 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3941 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
3944 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3945 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3946 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
3947 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
3951 static int __io_accept(struct io_kiocb
*req
, bool force_nonblock
)
3953 struct io_accept
*accept
= &req
->accept
;
3954 unsigned file_flags
;
3957 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
3958 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
3959 accept
->addr_len
, accept
->flags
,
3961 if (ret
== -EAGAIN
&& force_nonblock
)
3963 if (ret
== -ERESTARTSYS
)
3966 req_set_fail_links(req
);
3967 io_cqring_add_event(req
, ret
);
3972 static void io_accept_finish(struct io_wq_work
**workptr
)
3974 struct io_kiocb
*req
= container_of(*workptr
, struct io_kiocb
, work
);
3976 if (io_req_cancelled(req
))
3978 __io_accept(req
, false);
3979 io_steal_work(req
, workptr
);
3982 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
)
3986 ret
= __io_accept(req
, force_nonblock
);
3987 if (ret
== -EAGAIN
&& force_nonblock
) {
3988 req
->work
.func
= io_accept_finish
;
3994 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3996 struct io_connect
*conn
= &req
->connect
;
3997 struct io_async_ctx
*io
= req
->io
;
3999 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4001 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4004 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4005 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4010 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4011 &io
->connect
.address
);
4014 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
)
4016 struct io_async_ctx __io
, *io
;
4017 unsigned file_flags
;
4023 ret
= move_addr_to_kernel(req
->connect
.addr
,
4024 req
->connect
.addr_len
,
4025 &__io
.connect
.address
);
4031 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4033 ret
= __sys_connect_file(req
->file
, &io
->connect
.address
,
4034 req
->connect
.addr_len
, file_flags
);
4035 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4038 if (io_alloc_async_ctx(req
)) {
4042 memcpy(&req
->io
->connect
, &__io
.connect
, sizeof(__io
.connect
));
4045 if (ret
== -ERESTARTSYS
)
4049 req_set_fail_links(req
);
4050 io_cqring_add_event(req
, ret
);
4054 #else /* !CONFIG_NET */
4055 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4060 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
)
4065 static int io_send(struct io_kiocb
*req
, bool force_nonblock
)
4070 static int io_recvmsg_prep(struct io_kiocb
*req
,
4071 const struct io_uring_sqe
*sqe
)
4076 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
)
4081 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
)
4086 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4091 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
)
4096 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4101 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
)
4105 #endif /* CONFIG_NET */
4107 struct io_poll_table
{
4108 struct poll_table_struct pt
;
4109 struct io_kiocb
*req
;
4113 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4114 __poll_t mask
, task_work_func_t func
)
4116 struct task_struct
*tsk
;
4119 /* for instances that support it check for an event match first: */
4120 if (mask
&& !(mask
& poll
->events
))
4123 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4125 list_del_init(&poll
->wait
.entry
);
4129 init_task_work(&req
->task_work
, func
);
4131 * If this fails, then the task is exiting. When a task exits, the
4132 * work gets canceled, so just cancel this request as well instead
4133 * of executing it. We can't safely execute it anyway, as we may not
4134 * have the needed state needed for it anyway.
4136 ret
= task_work_add(tsk
, &req
->task_work
, true);
4137 if (unlikely(ret
)) {
4138 WRITE_ONCE(poll
->canceled
, true);
4139 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
4140 task_work_add(tsk
, &req
->task_work
, true);
4142 wake_up_process(tsk
);
4146 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4147 __acquires(&req
->ctx
->completion_lock
)
4149 struct io_ring_ctx
*ctx
= req
->ctx
;
4151 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4152 struct poll_table_struct pt
= { ._key
= poll
->events
};
4154 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4157 spin_lock_irq(&ctx
->completion_lock
);
4158 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4159 add_wait_queue(poll
->head
, &poll
->wait
);
4166 static void io_poll_remove_double(struct io_kiocb
*req
)
4168 struct io_poll_iocb
*poll
= (struct io_poll_iocb
*) req
->io
;
4170 lockdep_assert_held(&req
->ctx
->completion_lock
);
4172 if (poll
&& poll
->head
) {
4173 struct wait_queue_head
*head
= poll
->head
;
4175 spin_lock(&head
->lock
);
4176 list_del_init(&poll
->wait
.entry
);
4177 if (poll
->wait
.private)
4178 refcount_dec(&req
->refs
);
4180 spin_unlock(&head
->lock
);
4184 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4186 struct io_ring_ctx
*ctx
= req
->ctx
;
4188 io_poll_remove_double(req
);
4189 req
->poll
.done
= true;
4190 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
4191 io_commit_cqring(ctx
);
4194 static void io_poll_task_handler(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
4196 struct io_ring_ctx
*ctx
= req
->ctx
;
4198 if (io_poll_rewait(req
, &req
->poll
)) {
4199 spin_unlock_irq(&ctx
->completion_lock
);
4203 hash_del(&req
->hash_node
);
4204 io_poll_complete(req
, req
->result
, 0);
4205 req
->flags
|= REQ_F_COMP_LOCKED
;
4206 io_put_req_find_next(req
, nxt
);
4207 spin_unlock_irq(&ctx
->completion_lock
);
4209 io_cqring_ev_posted(ctx
);
4212 static void io_poll_task_func(struct callback_head
*cb
)
4214 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4215 struct io_kiocb
*nxt
= NULL
;
4217 io_poll_task_handler(req
, &nxt
);
4219 struct io_ring_ctx
*ctx
= nxt
->ctx
;
4221 mutex_lock(&ctx
->uring_lock
);
4222 __io_queue_sqe(nxt
, NULL
);
4223 mutex_unlock(&ctx
->uring_lock
);
4227 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4228 int sync
, void *key
)
4230 struct io_kiocb
*req
= wait
->private;
4231 struct io_poll_iocb
*poll
= (struct io_poll_iocb
*) req
->io
;
4232 __poll_t mask
= key_to_poll(key
);
4234 /* for instances that support it check for an event match first: */
4235 if (mask
&& !(mask
& poll
->events
))
4238 if (req
->poll
.head
) {
4241 spin_lock(&req
->poll
.head
->lock
);
4242 done
= list_empty(&req
->poll
.wait
.entry
);
4244 list_del_init(&req
->poll
.wait
.entry
);
4245 spin_unlock(&req
->poll
.head
->lock
);
4247 __io_async_wake(req
, poll
, mask
, io_poll_task_func
);
4249 refcount_dec(&req
->refs
);
4253 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
4254 wait_queue_func_t wake_func
)
4258 poll
->canceled
= false;
4259 poll
->events
= events
;
4260 INIT_LIST_HEAD(&poll
->wait
.entry
);
4261 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
4264 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
4265 struct wait_queue_head
*head
)
4267 struct io_kiocb
*req
= pt
->req
;
4270 * If poll->head is already set, it's because the file being polled
4271 * uses multiple waitqueues for poll handling (eg one for read, one
4272 * for write). Setup a separate io_poll_iocb if this happens.
4274 if (unlikely(poll
->head
)) {
4275 /* already have a 2nd entry, fail a third attempt */
4277 pt
->error
= -EINVAL
;
4280 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
4282 pt
->error
= -ENOMEM
;
4285 io_init_poll_iocb(poll
, req
->poll
.events
, io_poll_double_wake
);
4286 refcount_inc(&req
->refs
);
4287 poll
->wait
.private = req
;
4288 req
->io
= (void *) poll
;
4293 add_wait_queue(head
, &poll
->wait
);
4296 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4297 struct poll_table_struct
*p
)
4299 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4301 __io_queue_proc(&pt
->req
->apoll
->poll
, pt
, head
);
4304 static void io_async_task_func(struct callback_head
*cb
)
4306 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4307 struct async_poll
*apoll
= req
->apoll
;
4308 struct io_ring_ctx
*ctx
= req
->ctx
;
4309 bool canceled
= false;
4311 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
4313 if (io_poll_rewait(req
, &apoll
->poll
)) {
4314 spin_unlock_irq(&ctx
->completion_lock
);
4318 /* If req is still hashed, it cannot have been canceled. Don't check. */
4319 if (hash_hashed(&req
->hash_node
)) {
4320 hash_del(&req
->hash_node
);
4322 canceled
= READ_ONCE(apoll
->poll
.canceled
);
4324 io_cqring_fill_event(req
, -ECANCELED
);
4325 io_commit_cqring(ctx
);
4329 spin_unlock_irq(&ctx
->completion_lock
);
4331 /* restore ->work in case we need to retry again */
4332 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4336 __set_current_state(TASK_RUNNING
);
4337 mutex_lock(&ctx
->uring_lock
);
4338 __io_queue_sqe(req
, NULL
);
4339 mutex_unlock(&ctx
->uring_lock
);
4341 io_cqring_ev_posted(ctx
);
4342 req_set_fail_links(req
);
4343 io_double_put_req(req
);
4347 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4350 struct io_kiocb
*req
= wait
->private;
4351 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
4353 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
4356 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
4359 static void io_poll_req_insert(struct io_kiocb
*req
)
4361 struct io_ring_ctx
*ctx
= req
->ctx
;
4362 struct hlist_head
*list
;
4364 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
4365 hlist_add_head(&req
->hash_node
, list
);
4368 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
4369 struct io_poll_iocb
*poll
,
4370 struct io_poll_table
*ipt
, __poll_t mask
,
4371 wait_queue_func_t wake_func
)
4372 __acquires(&ctx
->completion_lock
)
4374 struct io_ring_ctx
*ctx
= req
->ctx
;
4375 bool cancel
= false;
4377 poll
->file
= req
->file
;
4378 io_init_poll_iocb(poll
, mask
, wake_func
);
4379 poll
->wait
.private = req
;
4381 ipt
->pt
._key
= mask
;
4383 ipt
->error
= -EINVAL
;
4385 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
4387 spin_lock_irq(&ctx
->completion_lock
);
4388 if (likely(poll
->head
)) {
4389 spin_lock(&poll
->head
->lock
);
4390 if (unlikely(list_empty(&poll
->wait
.entry
))) {
4396 if (mask
|| ipt
->error
)
4397 list_del_init(&poll
->wait
.entry
);
4399 WRITE_ONCE(poll
->canceled
, true);
4400 else if (!poll
->done
) /* actually waiting for an event */
4401 io_poll_req_insert(req
);
4402 spin_unlock(&poll
->head
->lock
);
4408 static bool io_arm_poll_handler(struct io_kiocb
*req
)
4410 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
4411 struct io_ring_ctx
*ctx
= req
->ctx
;
4412 struct async_poll
*apoll
;
4413 struct io_poll_table ipt
;
4417 if (!req
->file
|| !file_can_poll(req
->file
))
4419 if (req
->flags
& (REQ_F_MUST_PUNT
| REQ_F_POLLED
))
4421 if (!def
->pollin
&& !def
->pollout
)
4424 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
4425 if (unlikely(!apoll
))
4428 req
->flags
|= REQ_F_POLLED
;
4429 memcpy(&apoll
->work
, &req
->work
, sizeof(req
->work
));
4430 had_io
= req
->io
!= NULL
;
4432 get_task_struct(current
);
4433 req
->task
= current
;
4435 INIT_HLIST_NODE(&req
->hash_node
);
4439 mask
|= POLLIN
| POLLRDNORM
;
4441 mask
|= POLLOUT
| POLLWRNORM
;
4442 mask
|= POLLERR
| POLLPRI
;
4444 ipt
.pt
._qproc
= io_async_queue_proc
;
4446 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
4450 /* only remove double add if we did it here */
4452 io_poll_remove_double(req
);
4453 spin_unlock_irq(&ctx
->completion_lock
);
4454 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4458 spin_unlock_irq(&ctx
->completion_lock
);
4459 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
4460 apoll
->poll
.events
);
4464 static bool __io_poll_remove_one(struct io_kiocb
*req
,
4465 struct io_poll_iocb
*poll
)
4467 bool do_complete
= false;
4469 spin_lock(&poll
->head
->lock
);
4470 WRITE_ONCE(poll
->canceled
, true);
4471 if (!list_empty(&poll
->wait
.entry
)) {
4472 list_del_init(&poll
->wait
.entry
);
4475 spin_unlock(&poll
->head
->lock
);
4476 hash_del(&req
->hash_node
);
4480 static bool io_poll_remove_one(struct io_kiocb
*req
)
4484 if (req
->opcode
== IORING_OP_POLL_ADD
) {
4485 io_poll_remove_double(req
);
4486 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
4488 struct async_poll
*apoll
= req
->apoll
;
4490 /* non-poll requests have submit ref still */
4491 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
4495 * restore ->work because we will call
4496 * io_req_work_drop_env below when dropping the
4499 memcpy(&req
->work
, &apoll
->work
, sizeof(req
->work
));
4505 io_cqring_fill_event(req
, -ECANCELED
);
4506 io_commit_cqring(req
->ctx
);
4507 req
->flags
|= REQ_F_COMP_LOCKED
;
4514 static void io_poll_remove_all(struct io_ring_ctx
*ctx
)
4516 struct hlist_node
*tmp
;
4517 struct io_kiocb
*req
;
4520 spin_lock_irq(&ctx
->completion_lock
);
4521 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
4522 struct hlist_head
*list
;
4524 list
= &ctx
->cancel_hash
[i
];
4525 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
)
4526 posted
+= io_poll_remove_one(req
);
4528 spin_unlock_irq(&ctx
->completion_lock
);
4531 io_cqring_ev_posted(ctx
);
4534 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
4536 struct hlist_head
*list
;
4537 struct io_kiocb
*req
;
4539 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
4540 hlist_for_each_entry(req
, list
, hash_node
) {
4541 if (sqe_addr
!= req
->user_data
)
4543 if (io_poll_remove_one(req
))
4551 static int io_poll_remove_prep(struct io_kiocb
*req
,
4552 const struct io_uring_sqe
*sqe
)
4554 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4556 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
4560 req
->poll
.addr
= READ_ONCE(sqe
->addr
);
4565 * Find a running poll command that matches one specified in sqe->addr,
4566 * and remove it if found.
4568 static int io_poll_remove(struct io_kiocb
*req
)
4570 struct io_ring_ctx
*ctx
= req
->ctx
;
4574 addr
= req
->poll
.addr
;
4575 spin_lock_irq(&ctx
->completion_lock
);
4576 ret
= io_poll_cancel(ctx
, addr
);
4577 spin_unlock_irq(&ctx
->completion_lock
);
4579 io_cqring_add_event(req
, ret
);
4581 req_set_fail_links(req
);
4586 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4589 struct io_kiocb
*req
= wait
->private;
4590 struct io_poll_iocb
*poll
= &req
->poll
;
4592 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
4595 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4596 struct poll_table_struct
*p
)
4598 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4600 __io_queue_proc(&pt
->req
->poll
, pt
, head
);
4603 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4605 struct io_poll_iocb
*poll
= &req
->poll
;
4608 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4610 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
4615 events
= READ_ONCE(sqe
->poll_events
);
4616 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
;
4618 get_task_struct(current
);
4619 req
->task
= current
;
4623 static int io_poll_add(struct io_kiocb
*req
)
4625 struct io_poll_iocb
*poll
= &req
->poll
;
4626 struct io_ring_ctx
*ctx
= req
->ctx
;
4627 struct io_poll_table ipt
;
4630 INIT_HLIST_NODE(&req
->hash_node
);
4631 INIT_LIST_HEAD(&req
->list
);
4632 ipt
.pt
._qproc
= io_poll_queue_proc
;
4634 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
4637 if (mask
) { /* no async, we'd stolen it */
4639 io_poll_complete(req
, mask
, 0);
4641 spin_unlock_irq(&ctx
->completion_lock
);
4644 io_cqring_ev_posted(ctx
);
4650 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
4652 struct io_timeout_data
*data
= container_of(timer
,
4653 struct io_timeout_data
, timer
);
4654 struct io_kiocb
*req
= data
->req
;
4655 struct io_ring_ctx
*ctx
= req
->ctx
;
4656 unsigned long flags
;
4658 atomic_inc(&ctx
->cq_timeouts
);
4660 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4662 * We could be racing with timeout deletion. If the list is empty,
4663 * then timeout lookup already found it and will be handling it.
4665 if (!list_empty(&req
->list
))
4666 list_del_init(&req
->list
);
4668 io_cqring_fill_event(req
, -ETIME
);
4669 io_commit_cqring(ctx
);
4670 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
4672 io_cqring_ev_posted(ctx
);
4673 req_set_fail_links(req
);
4675 return HRTIMER_NORESTART
;
4678 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
4680 struct io_kiocb
*req
;
4683 list_for_each_entry(req
, &ctx
->timeout_list
, list
) {
4684 if (user_data
== req
->user_data
) {
4685 list_del_init(&req
->list
);
4694 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
4698 req_set_fail_links(req
);
4699 io_cqring_fill_event(req
, -ECANCELED
);
4704 static int io_timeout_remove_prep(struct io_kiocb
*req
,
4705 const struct io_uring_sqe
*sqe
)
4707 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4709 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
4712 req
->timeout
.addr
= READ_ONCE(sqe
->addr
);
4713 req
->timeout
.flags
= READ_ONCE(sqe
->timeout_flags
);
4714 if (req
->timeout
.flags
)
4721 * Remove or update an existing timeout command
4723 static int io_timeout_remove(struct io_kiocb
*req
)
4725 struct io_ring_ctx
*ctx
= req
->ctx
;
4728 spin_lock_irq(&ctx
->completion_lock
);
4729 ret
= io_timeout_cancel(ctx
, req
->timeout
.addr
);
4731 io_cqring_fill_event(req
, ret
);
4732 io_commit_cqring(ctx
);
4733 spin_unlock_irq(&ctx
->completion_lock
);
4734 io_cqring_ev_posted(ctx
);
4736 req_set_fail_links(req
);
4741 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
4742 bool is_timeout_link
)
4744 struct io_timeout_data
*data
;
4746 u32 off
= READ_ONCE(sqe
->off
);
4748 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4750 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
4752 if (off
&& is_timeout_link
)
4754 flags
= READ_ONCE(sqe
->timeout_flags
);
4755 if (flags
& ~IORING_TIMEOUT_ABS
)
4758 req
->timeout
.off
= off
;
4760 if (!req
->io
&& io_alloc_async_ctx(req
))
4763 data
= &req
->io
->timeout
;
4765 req
->flags
|= REQ_F_TIMEOUT
;
4767 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
4770 if (flags
& IORING_TIMEOUT_ABS
)
4771 data
->mode
= HRTIMER_MODE_ABS
;
4773 data
->mode
= HRTIMER_MODE_REL
;
4775 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
4779 static int io_timeout(struct io_kiocb
*req
)
4781 struct io_ring_ctx
*ctx
= req
->ctx
;
4782 struct io_timeout_data
*data
= &req
->io
->timeout
;
4783 struct list_head
*entry
;
4784 u32 tail
, off
= req
->timeout
.off
;
4786 spin_lock_irq(&ctx
->completion_lock
);
4789 * sqe->off holds how many events that need to occur for this
4790 * timeout event to be satisfied. If it isn't set, then this is
4791 * a pure timeout request, sequence isn't used.
4794 req
->flags
|= REQ_F_TIMEOUT_NOSEQ
;
4795 entry
= ctx
->timeout_list
.prev
;
4799 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
4800 req
->timeout
.target_seq
= tail
+ off
;
4803 * Insertion sort, ensuring the first entry in the list is always
4804 * the one we need first.
4806 list_for_each_prev(entry
, &ctx
->timeout_list
) {
4807 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
, list
);
4809 if (nxt
->flags
& REQ_F_TIMEOUT_NOSEQ
)
4811 /* nxt.seq is behind @tail, otherwise would've been completed */
4812 if (off
>= nxt
->timeout
.target_seq
- tail
)
4816 list_add(&req
->list
, entry
);
4817 data
->timer
.function
= io_timeout_fn
;
4818 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
4819 spin_unlock_irq(&ctx
->completion_lock
);
4823 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
4825 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
4827 return req
->user_data
== (unsigned long) data
;
4830 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
4832 enum io_wq_cancel cancel_ret
;
4835 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
);
4836 switch (cancel_ret
) {
4837 case IO_WQ_CANCEL_OK
:
4840 case IO_WQ_CANCEL_RUNNING
:
4843 case IO_WQ_CANCEL_NOTFOUND
:
4851 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
4852 struct io_kiocb
*req
, __u64 sqe_addr
,
4855 unsigned long flags
;
4858 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
4859 if (ret
!= -ENOENT
) {
4860 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4864 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
4865 ret
= io_timeout_cancel(ctx
, sqe_addr
);
4868 ret
= io_poll_cancel(ctx
, sqe_addr
);
4872 io_cqring_fill_event(req
, ret
);
4873 io_commit_cqring(ctx
);
4874 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
4875 io_cqring_ev_posted(ctx
);
4878 req_set_fail_links(req
);
4882 static int io_async_cancel_prep(struct io_kiocb
*req
,
4883 const struct io_uring_sqe
*sqe
)
4885 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4887 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
||
4891 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
4895 static int io_async_cancel(struct io_kiocb
*req
)
4897 struct io_ring_ctx
*ctx
= req
->ctx
;
4899 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
4903 static int io_files_update_prep(struct io_kiocb
*req
,
4904 const struct io_uring_sqe
*sqe
)
4906 if (sqe
->flags
|| sqe
->ioprio
|| sqe
->rw_flags
)
4909 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
4910 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
4911 if (!req
->files_update
.nr_args
)
4913 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
4917 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
)
4919 struct io_ring_ctx
*ctx
= req
->ctx
;
4920 struct io_uring_files_update up
;
4926 up
.offset
= req
->files_update
.offset
;
4927 up
.fds
= req
->files_update
.arg
;
4929 mutex_lock(&ctx
->uring_lock
);
4930 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
4931 mutex_unlock(&ctx
->uring_lock
);
4934 req_set_fail_links(req
);
4935 io_cqring_add_event(req
, ret
);
4940 static int io_req_defer_prep(struct io_kiocb
*req
,
4941 const struct io_uring_sqe
*sqe
)
4948 if (io_op_defs
[req
->opcode
].file_table
) {
4949 ret
= io_grab_files(req
);
4954 io_req_work_grab_env(req
, &io_op_defs
[req
->opcode
]);
4956 switch (req
->opcode
) {
4959 case IORING_OP_READV
:
4960 case IORING_OP_READ_FIXED
:
4961 case IORING_OP_READ
:
4962 ret
= io_read_prep(req
, sqe
, true);
4964 case IORING_OP_WRITEV
:
4965 case IORING_OP_WRITE_FIXED
:
4966 case IORING_OP_WRITE
:
4967 ret
= io_write_prep(req
, sqe
, true);
4969 case IORING_OP_POLL_ADD
:
4970 ret
= io_poll_add_prep(req
, sqe
);
4972 case IORING_OP_POLL_REMOVE
:
4973 ret
= io_poll_remove_prep(req
, sqe
);
4975 case IORING_OP_FSYNC
:
4976 ret
= io_prep_fsync(req
, sqe
);
4978 case IORING_OP_SYNC_FILE_RANGE
:
4979 ret
= io_prep_sfr(req
, sqe
);
4981 case IORING_OP_SENDMSG
:
4982 case IORING_OP_SEND
:
4983 ret
= io_sendmsg_prep(req
, sqe
);
4985 case IORING_OP_RECVMSG
:
4986 case IORING_OP_RECV
:
4987 ret
= io_recvmsg_prep(req
, sqe
);
4989 case IORING_OP_CONNECT
:
4990 ret
= io_connect_prep(req
, sqe
);
4992 case IORING_OP_TIMEOUT
:
4993 ret
= io_timeout_prep(req
, sqe
, false);
4995 case IORING_OP_TIMEOUT_REMOVE
:
4996 ret
= io_timeout_remove_prep(req
, sqe
);
4998 case IORING_OP_ASYNC_CANCEL
:
4999 ret
= io_async_cancel_prep(req
, sqe
);
5001 case IORING_OP_LINK_TIMEOUT
:
5002 ret
= io_timeout_prep(req
, sqe
, true);
5004 case IORING_OP_ACCEPT
:
5005 ret
= io_accept_prep(req
, sqe
);
5007 case IORING_OP_FALLOCATE
:
5008 ret
= io_fallocate_prep(req
, sqe
);
5010 case IORING_OP_OPENAT
:
5011 ret
= io_openat_prep(req
, sqe
);
5013 case IORING_OP_CLOSE
:
5014 ret
= io_close_prep(req
, sqe
);
5016 case IORING_OP_FILES_UPDATE
:
5017 ret
= io_files_update_prep(req
, sqe
);
5019 case IORING_OP_STATX
:
5020 ret
= io_statx_prep(req
, sqe
);
5022 case IORING_OP_FADVISE
:
5023 ret
= io_fadvise_prep(req
, sqe
);
5025 case IORING_OP_MADVISE
:
5026 ret
= io_madvise_prep(req
, sqe
);
5028 case IORING_OP_OPENAT2
:
5029 ret
= io_openat2_prep(req
, sqe
);
5031 case IORING_OP_EPOLL_CTL
:
5032 ret
= io_epoll_ctl_prep(req
, sqe
);
5034 case IORING_OP_SPLICE
:
5035 ret
= io_splice_prep(req
, sqe
);
5037 case IORING_OP_PROVIDE_BUFFERS
:
5038 ret
= io_provide_buffers_prep(req
, sqe
);
5040 case IORING_OP_REMOVE_BUFFERS
:
5041 ret
= io_remove_buffers_prep(req
, sqe
);
5044 ret
= io_tee_prep(req
, sqe
);
5047 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5056 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5058 struct io_ring_ctx
*ctx
= req
->ctx
;
5061 /* Still need defer if there is pending req in defer list. */
5062 if (!req_need_defer(req
) && list_empty_careful(&ctx
->defer_list
))
5066 if (io_alloc_async_ctx(req
))
5068 ret
= io_req_defer_prep(req
, sqe
);
5073 spin_lock_irq(&ctx
->completion_lock
);
5074 if (!req_need_defer(req
) && list_empty(&ctx
->defer_list
)) {
5075 spin_unlock_irq(&ctx
->completion_lock
);
5079 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5080 list_add_tail(&req
->list
, &ctx
->defer_list
);
5081 spin_unlock_irq(&ctx
->completion_lock
);
5082 return -EIOCBQUEUED
;
5085 static void io_cleanup_req(struct io_kiocb
*req
)
5087 struct io_async_ctx
*io
= req
->io
;
5089 switch (req
->opcode
) {
5090 case IORING_OP_READV
:
5091 case IORING_OP_READ_FIXED
:
5092 case IORING_OP_READ
:
5093 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5094 kfree((void *)(unsigned long)req
->rw
.addr
);
5096 case IORING_OP_WRITEV
:
5097 case IORING_OP_WRITE_FIXED
:
5098 case IORING_OP_WRITE
:
5099 if (io
->rw
.iov
!= io
->rw
.fast_iov
)
5102 case IORING_OP_RECVMSG
:
5103 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5104 kfree(req
->sr_msg
.kbuf
);
5106 case IORING_OP_SENDMSG
:
5107 if (io
->msg
.iov
!= io
->msg
.fast_iov
)
5110 case IORING_OP_RECV
:
5111 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
5112 kfree(req
->sr_msg
.kbuf
);
5114 case IORING_OP_OPENAT
:
5115 case IORING_OP_OPENAT2
:
5117 case IORING_OP_SPLICE
:
5119 io_put_file(req
, req
->splice
.file_in
,
5120 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
5124 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5127 static int io_issue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5128 bool force_nonblock
)
5130 struct io_ring_ctx
*ctx
= req
->ctx
;
5133 switch (req
->opcode
) {
5137 case IORING_OP_READV
:
5138 case IORING_OP_READ_FIXED
:
5139 case IORING_OP_READ
:
5141 ret
= io_read_prep(req
, sqe
, force_nonblock
);
5145 ret
= io_read(req
, force_nonblock
);
5147 case IORING_OP_WRITEV
:
5148 case IORING_OP_WRITE_FIXED
:
5149 case IORING_OP_WRITE
:
5151 ret
= io_write_prep(req
, sqe
, force_nonblock
);
5155 ret
= io_write(req
, force_nonblock
);
5157 case IORING_OP_FSYNC
:
5159 ret
= io_prep_fsync(req
, sqe
);
5163 ret
= io_fsync(req
, force_nonblock
);
5165 case IORING_OP_POLL_ADD
:
5167 ret
= io_poll_add_prep(req
, sqe
);
5171 ret
= io_poll_add(req
);
5173 case IORING_OP_POLL_REMOVE
:
5175 ret
= io_poll_remove_prep(req
, sqe
);
5179 ret
= io_poll_remove(req
);
5181 case IORING_OP_SYNC_FILE_RANGE
:
5183 ret
= io_prep_sfr(req
, sqe
);
5187 ret
= io_sync_file_range(req
, force_nonblock
);
5189 case IORING_OP_SENDMSG
:
5190 case IORING_OP_SEND
:
5192 ret
= io_sendmsg_prep(req
, sqe
);
5196 if (req
->opcode
== IORING_OP_SENDMSG
)
5197 ret
= io_sendmsg(req
, force_nonblock
);
5199 ret
= io_send(req
, force_nonblock
);
5201 case IORING_OP_RECVMSG
:
5202 case IORING_OP_RECV
:
5204 ret
= io_recvmsg_prep(req
, sqe
);
5208 if (req
->opcode
== IORING_OP_RECVMSG
)
5209 ret
= io_recvmsg(req
, force_nonblock
);
5211 ret
= io_recv(req
, force_nonblock
);
5213 case IORING_OP_TIMEOUT
:
5215 ret
= io_timeout_prep(req
, sqe
, false);
5219 ret
= io_timeout(req
);
5221 case IORING_OP_TIMEOUT_REMOVE
:
5223 ret
= io_timeout_remove_prep(req
, sqe
);
5227 ret
= io_timeout_remove(req
);
5229 case IORING_OP_ACCEPT
:
5231 ret
= io_accept_prep(req
, sqe
);
5235 ret
= io_accept(req
, force_nonblock
);
5237 case IORING_OP_CONNECT
:
5239 ret
= io_connect_prep(req
, sqe
);
5243 ret
= io_connect(req
, force_nonblock
);
5245 case IORING_OP_ASYNC_CANCEL
:
5247 ret
= io_async_cancel_prep(req
, sqe
);
5251 ret
= io_async_cancel(req
);
5253 case IORING_OP_FALLOCATE
:
5255 ret
= io_fallocate_prep(req
, sqe
);
5259 ret
= io_fallocate(req
, force_nonblock
);
5261 case IORING_OP_OPENAT
:
5263 ret
= io_openat_prep(req
, sqe
);
5267 ret
= io_openat(req
, force_nonblock
);
5269 case IORING_OP_CLOSE
:
5271 ret
= io_close_prep(req
, sqe
);
5275 ret
= io_close(req
, force_nonblock
);
5277 case IORING_OP_FILES_UPDATE
:
5279 ret
= io_files_update_prep(req
, sqe
);
5283 ret
= io_files_update(req
, force_nonblock
);
5285 case IORING_OP_STATX
:
5287 ret
= io_statx_prep(req
, sqe
);
5291 ret
= io_statx(req
, force_nonblock
);
5293 case IORING_OP_FADVISE
:
5295 ret
= io_fadvise_prep(req
, sqe
);
5299 ret
= io_fadvise(req
, force_nonblock
);
5301 case IORING_OP_MADVISE
:
5303 ret
= io_madvise_prep(req
, sqe
);
5307 ret
= io_madvise(req
, force_nonblock
);
5309 case IORING_OP_OPENAT2
:
5311 ret
= io_openat2_prep(req
, sqe
);
5315 ret
= io_openat2(req
, force_nonblock
);
5317 case IORING_OP_EPOLL_CTL
:
5319 ret
= io_epoll_ctl_prep(req
, sqe
);
5323 ret
= io_epoll_ctl(req
, force_nonblock
);
5325 case IORING_OP_SPLICE
:
5327 ret
= io_splice_prep(req
, sqe
);
5331 ret
= io_splice(req
, force_nonblock
);
5333 case IORING_OP_PROVIDE_BUFFERS
:
5335 ret
= io_provide_buffers_prep(req
, sqe
);
5339 ret
= io_provide_buffers(req
, force_nonblock
);
5341 case IORING_OP_REMOVE_BUFFERS
:
5343 ret
= io_remove_buffers_prep(req
, sqe
);
5347 ret
= io_remove_buffers(req
, force_nonblock
);
5351 ret
= io_tee_prep(req
, sqe
);
5355 ret
= io_tee(req
, force_nonblock
);
5365 /* If the op doesn't have a file, we're not polling for it */
5366 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
5367 const bool in_async
= io_wq_current_is_worker();
5369 if (req
->result
== -EAGAIN
)
5372 /* workqueue context doesn't hold uring_lock, grab it now */
5374 mutex_lock(&ctx
->uring_lock
);
5376 io_iopoll_req_issued(req
);
5379 mutex_unlock(&ctx
->uring_lock
);
5385 static void io_wq_submit_work(struct io_wq_work
**workptr
)
5387 struct io_wq_work
*work
= *workptr
;
5388 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5391 /* if NO_CANCEL is set, we must still run the work */
5392 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
5393 IO_WQ_WORK_CANCEL
) {
5399 ret
= io_issue_sqe(req
, NULL
, false);
5401 * We can get EAGAIN for polled IO even though we're
5402 * forcing a sync submission from here, since we can't
5403 * wait for request slots on the block side.
5412 req_set_fail_links(req
);
5413 io_cqring_add_event(req
, ret
);
5417 io_steal_work(req
, workptr
);
5420 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
5423 struct fixed_file_table
*table
;
5425 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
5426 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
5429 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
5430 int fd
, struct file
**out_file
, bool fixed
)
5432 struct io_ring_ctx
*ctx
= req
->ctx
;
5436 if (unlikely(!ctx
->file_data
||
5437 (unsigned) fd
>= ctx
->nr_user_files
))
5439 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
5440 file
= io_file_from_index(ctx
, fd
);
5443 req
->fixed_file_refs
= ctx
->file_data
->cur_refs
;
5444 percpu_ref_get(req
->fixed_file_refs
);
5446 trace_io_uring_file_get(ctx
, fd
);
5447 file
= __io_file_get(state
, fd
);
5448 if (unlikely(!file
))
5456 static int io_req_set_file(struct io_submit_state
*state
, struct io_kiocb
*req
,
5461 fixed
= (req
->flags
& REQ_F_FIXED_FILE
) != 0;
5462 if (unlikely(!fixed
&& io_async_submit(req
->ctx
)))
5465 return io_file_get(state
, req
, fd
, &req
->file
, fixed
);
5468 static int io_grab_files(struct io_kiocb
*req
)
5471 struct io_ring_ctx
*ctx
= req
->ctx
;
5473 if (req
->work
.files
|| (req
->flags
& REQ_F_NO_FILE_TABLE
))
5475 if (!ctx
->ring_file
)
5479 spin_lock_irq(&ctx
->inflight_lock
);
5481 * We use the f_ops->flush() handler to ensure that we can flush
5482 * out work accessing these files if the fd is closed. Check if
5483 * the fd has changed since we started down this path, and disallow
5484 * this operation if it has.
5486 if (fcheck(ctx
->ring_fd
) == ctx
->ring_file
) {
5487 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
5488 req
->flags
|= REQ_F_INFLIGHT
;
5489 req
->work
.files
= current
->files
;
5492 spin_unlock_irq(&ctx
->inflight_lock
);
5498 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
5500 struct io_timeout_data
*data
= container_of(timer
,
5501 struct io_timeout_data
, timer
);
5502 struct io_kiocb
*req
= data
->req
;
5503 struct io_ring_ctx
*ctx
= req
->ctx
;
5504 struct io_kiocb
*prev
= NULL
;
5505 unsigned long flags
;
5507 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5510 * We don't expect the list to be empty, that will only happen if we
5511 * race with the completion of the linked work.
5513 if (!list_empty(&req
->link_list
)) {
5514 prev
= list_entry(req
->link_list
.prev
, struct io_kiocb
,
5516 if (refcount_inc_not_zero(&prev
->refs
)) {
5517 list_del_init(&req
->link_list
);
5518 prev
->flags
&= ~REQ_F_LINK_TIMEOUT
;
5523 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5526 req_set_fail_links(prev
);
5527 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
5530 io_cqring_add_event(req
, -ETIME
);
5533 return HRTIMER_NORESTART
;
5536 static void io_queue_linked_timeout(struct io_kiocb
*req
)
5538 struct io_ring_ctx
*ctx
= req
->ctx
;
5541 * If the list is now empty, then our linked request finished before
5542 * we got a chance to setup the timer
5544 spin_lock_irq(&ctx
->completion_lock
);
5545 if (!list_empty(&req
->link_list
)) {
5546 struct io_timeout_data
*data
= &req
->io
->timeout
;
5548 data
->timer
.function
= io_link_timeout_fn
;
5549 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
5552 spin_unlock_irq(&ctx
->completion_lock
);
5554 /* drop submission reference */
5558 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
5560 struct io_kiocb
*nxt
;
5562 if (!(req
->flags
& REQ_F_LINK_HEAD
))
5564 /* for polled retry, if flag is set, we already went through here */
5565 if (req
->flags
& REQ_F_POLLED
)
5568 nxt
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
5570 if (!nxt
|| nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
5573 req
->flags
|= REQ_F_LINK_TIMEOUT
;
5577 static void __io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5579 struct io_kiocb
*linked_timeout
;
5580 struct io_kiocb
*nxt
;
5581 const struct cred
*old_creds
= NULL
;
5585 linked_timeout
= io_prep_linked_timeout(req
);
5587 if (req
->work
.creds
&& req
->work
.creds
!= current_cred()) {
5589 revert_creds(old_creds
);
5590 if (old_creds
== req
->work
.creds
)
5591 old_creds
= NULL
; /* restored original creds */
5593 old_creds
= override_creds(req
->work
.creds
);
5596 ret
= io_issue_sqe(req
, sqe
, true);
5599 * We async punt it if the file wasn't marked NOWAIT, or if the file
5600 * doesn't support non-blocking read/write attempts
5602 if (ret
== -EAGAIN
&& (!(req
->flags
& REQ_F_NOWAIT
) ||
5603 (req
->flags
& REQ_F_MUST_PUNT
))) {
5604 if (io_arm_poll_handler(req
)) {
5606 io_queue_linked_timeout(linked_timeout
);
5610 if (io_op_defs
[req
->opcode
].file_table
) {
5611 ret
= io_grab_files(req
);
5617 * Queued up for async execution, worker will release
5618 * submit reference when the iocb is actually submitted.
5620 io_queue_async_work(req
);
5626 /* drop submission reference */
5627 io_put_req_find_next(req
, &nxt
);
5629 if (linked_timeout
) {
5631 io_queue_linked_timeout(linked_timeout
);
5633 io_put_req(linked_timeout
);
5636 /* and drop final reference, if we failed */
5638 io_cqring_add_event(req
, ret
);
5639 req_set_fail_links(req
);
5645 if (req
->flags
& REQ_F_FORCE_ASYNC
)
5651 revert_creds(old_creds
);
5654 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5658 ret
= io_req_defer(req
, sqe
);
5660 if (ret
!= -EIOCBQUEUED
) {
5662 io_cqring_add_event(req
, ret
);
5663 req_set_fail_links(req
);
5664 io_double_put_req(req
);
5666 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
5669 if (io_alloc_async_ctx(req
))
5671 ret
= io_req_defer_prep(req
, sqe
);
5672 if (unlikely(ret
< 0))
5677 * Never try inline submit of IOSQE_ASYNC is set, go straight
5678 * to async execution.
5680 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
5681 io_queue_async_work(req
);
5683 __io_queue_sqe(req
, sqe
);
5687 static inline void io_queue_link_head(struct io_kiocb
*req
)
5689 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
5690 io_cqring_add_event(req
, -ECANCELED
);
5691 io_double_put_req(req
);
5693 io_queue_sqe(req
, NULL
);
5696 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5697 struct io_kiocb
**link
)
5699 struct io_ring_ctx
*ctx
= req
->ctx
;
5703 * If we already have a head request, queue this one for async
5704 * submittal once the head completes. If we don't have a head but
5705 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
5706 * submitted sync once the chain is complete. If none of those
5707 * conditions are true (normal request), then just queue it.
5710 struct io_kiocb
*head
= *link
;
5713 * Taking sequential execution of a link, draining both sides
5714 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
5715 * requests in the link. So, it drains the head and the
5716 * next after the link request. The last one is done via
5717 * drain_next flag to persist the effect across calls.
5719 if (req
->flags
& REQ_F_IO_DRAIN
) {
5720 head
->flags
|= REQ_F_IO_DRAIN
;
5721 ctx
->drain_next
= 1;
5723 if (io_alloc_async_ctx(req
))
5726 ret
= io_req_defer_prep(req
, sqe
);
5728 /* fail even hard links since we don't submit */
5729 head
->flags
|= REQ_F_FAIL_LINK
;
5732 trace_io_uring_link(ctx
, req
, head
);
5733 list_add_tail(&req
->link_list
, &head
->link_list
);
5735 /* last request of a link, enqueue the link */
5736 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
5737 io_queue_link_head(head
);
5741 if (unlikely(ctx
->drain_next
)) {
5742 req
->flags
|= REQ_F_IO_DRAIN
;
5743 ctx
->drain_next
= 0;
5745 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
5746 req
->flags
|= REQ_F_LINK_HEAD
;
5747 INIT_LIST_HEAD(&req
->link_list
);
5749 if (io_alloc_async_ctx(req
))
5752 ret
= io_req_defer_prep(req
, sqe
);
5754 req
->flags
|= REQ_F_FAIL_LINK
;
5757 io_queue_sqe(req
, sqe
);
5765 * Batched submission is done, ensure local IO is flushed out.
5767 static void io_submit_state_end(struct io_submit_state
*state
)
5769 blk_finish_plug(&state
->plug
);
5770 io_state_file_put(state
);
5771 if (state
->free_reqs
)
5772 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
5776 * Start submission side cache.
5778 static void io_submit_state_start(struct io_submit_state
*state
,
5779 unsigned int max_ios
)
5781 blk_start_plug(&state
->plug
);
5782 state
->free_reqs
= 0;
5784 state
->ios_left
= max_ios
;
5787 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
5789 struct io_rings
*rings
= ctx
->rings
;
5792 * Ensure any loads from the SQEs are done at this point,
5793 * since once we write the new head, the application could
5794 * write new data to them.
5796 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
5800 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
5801 * that is mapped by userspace. This means that care needs to be taken to
5802 * ensure that reads are stable, as we cannot rely on userspace always
5803 * being a good citizen. If members of the sqe are validated and then later
5804 * used, it's important that those reads are done through READ_ONCE() to
5805 * prevent a re-load down the line.
5807 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
5809 u32
*sq_array
= ctx
->sq_array
;
5813 * The cached sq head (or cq tail) serves two purposes:
5815 * 1) allows us to batch the cost of updating the user visible
5817 * 2) allows the kernel side to track the head on its own, even
5818 * though the application is the one updating it.
5820 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
5821 if (likely(head
< ctx
->sq_entries
))
5822 return &ctx
->sq_sqes
[head
];
5824 /* drop invalid entries */
5825 ctx
->cached_sq_dropped
++;
5826 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
5830 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
5832 ctx
->cached_sq_head
++;
5835 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
5836 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
5837 IOSQE_BUFFER_SELECT)
5839 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
5840 const struct io_uring_sqe
*sqe
,
5841 struct io_submit_state
*state
)
5843 unsigned int sqe_flags
;
5847 * All io need record the previous position, if LINK vs DARIN,
5848 * it can be used to mark the position of the first IO in the
5851 req
->sequence
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5852 req
->opcode
= READ_ONCE(sqe
->opcode
);
5853 req
->user_data
= READ_ONCE(sqe
->user_data
);
5858 /* one is dropped after submission, the other at completion */
5859 refcount_set(&req
->refs
, 2);
5862 INIT_IO_WORK(&req
->work
, io_wq_submit_work
);
5864 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
5867 if (io_op_defs
[req
->opcode
].needs_mm
&& !current
->mm
) {
5868 if (unlikely(!mmget_not_zero(ctx
->sqo_mm
)))
5870 use_mm(ctx
->sqo_mm
);
5873 sqe_flags
= READ_ONCE(sqe
->flags
);
5874 /* enforce forwards compatibility on users */
5875 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
5878 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
5879 !io_op_defs
[req
->opcode
].buffer_select
)
5882 id
= READ_ONCE(sqe
->personality
);
5884 req
->work
.creds
= idr_find(&ctx
->personality_idr
, id
);
5885 if (unlikely(!req
->work
.creds
))
5887 get_cred(req
->work
.creds
);
5890 /* same numerical values with corresponding REQ_F_*, safe to copy */
5891 req
->flags
|= sqe_flags
;
5893 if (!io_op_defs
[req
->opcode
].needs_file
)
5896 return io_req_set_file(state
, req
, READ_ONCE(sqe
->fd
));
5899 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
,
5900 struct file
*ring_file
, int ring_fd
)
5902 struct io_submit_state state
, *statep
= NULL
;
5903 struct io_kiocb
*link
= NULL
;
5904 int i
, submitted
= 0;
5906 /* if we have a backlog and couldn't flush it all, return BUSY */
5907 if (test_bit(0, &ctx
->sq_check_overflow
)) {
5908 if (!list_empty(&ctx
->cq_overflow_list
) &&
5909 !io_cqring_overflow_flush(ctx
, false))
5913 /* make sure SQ entry isn't read before tail */
5914 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
5916 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
5919 if (nr
> IO_PLUG_THRESHOLD
) {
5920 io_submit_state_start(&state
, nr
);
5924 ctx
->ring_fd
= ring_fd
;
5925 ctx
->ring_file
= ring_file
;
5927 for (i
= 0; i
< nr
; i
++) {
5928 const struct io_uring_sqe
*sqe
;
5929 struct io_kiocb
*req
;
5932 sqe
= io_get_sqe(ctx
);
5933 if (unlikely(!sqe
)) {
5934 io_consume_sqe(ctx
);
5937 req
= io_alloc_req(ctx
, statep
);
5938 if (unlikely(!req
)) {
5940 submitted
= -EAGAIN
;
5944 err
= io_init_req(ctx
, req
, sqe
, statep
);
5945 io_consume_sqe(ctx
);
5946 /* will complete beyond this point, count as submitted */
5949 if (unlikely(err
)) {
5951 io_cqring_add_event(req
, err
);
5952 io_double_put_req(req
);
5956 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
5957 true, io_async_submit(ctx
));
5958 err
= io_submit_sqe(req
, sqe
, &link
);
5963 if (unlikely(submitted
!= nr
)) {
5964 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
5966 percpu_ref_put_many(&ctx
->refs
, nr
- ref_used
);
5969 io_queue_link_head(link
);
5971 io_submit_state_end(&state
);
5973 /* Commit SQ ring head once we've consumed and submitted all SQEs */
5974 io_commit_sqring(ctx
);
5979 static inline void io_sq_thread_drop_mm(struct io_ring_ctx
*ctx
)
5981 struct mm_struct
*mm
= current
->mm
;
5989 static int io_sq_thread(void *data
)
5991 struct io_ring_ctx
*ctx
= data
;
5992 const struct cred
*old_cred
;
5993 mm_segment_t old_fs
;
5995 unsigned long timeout
;
5998 complete(&ctx
->sq_thread_comp
);
6002 old_cred
= override_creds(ctx
->creds
);
6004 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6005 while (!kthread_should_park()) {
6006 unsigned int to_submit
;
6008 if (!list_empty(&ctx
->poll_list
)) {
6009 unsigned nr_events
= 0;
6011 mutex_lock(&ctx
->uring_lock
);
6012 if (!list_empty(&ctx
->poll_list
))
6013 io_iopoll_getevents(ctx
, &nr_events
, 0);
6015 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6016 mutex_unlock(&ctx
->uring_lock
);
6019 to_submit
= io_sqring_entries(ctx
);
6022 * If submit got -EBUSY, flag us as needing the application
6023 * to enter the kernel to reap and flush events.
6025 if (!to_submit
|| ret
== -EBUSY
) {
6027 * Drop cur_mm before scheduling, we can't hold it for
6028 * long periods (or over schedule()). Do this before
6029 * adding ourselves to the waitqueue, as the unuse/drop
6032 io_sq_thread_drop_mm(ctx
);
6035 * We're polling. If we're within the defined idle
6036 * period, then let us spin without work before going
6037 * to sleep. The exception is if we got EBUSY doing
6038 * more IO, we should wait for the application to
6039 * reap events and wake us up.
6041 if (!list_empty(&ctx
->poll_list
) ||
6042 (!time_after(jiffies
, timeout
) && ret
!= -EBUSY
&&
6043 !percpu_ref_is_dying(&ctx
->refs
))) {
6044 if (current
->task_works
)
6050 prepare_to_wait(&ctx
->sqo_wait
, &wait
,
6051 TASK_INTERRUPTIBLE
);
6054 * While doing polled IO, before going to sleep, we need
6055 * to check if there are new reqs added to poll_list, it
6056 * is because reqs may have been punted to io worker and
6057 * will be added to poll_list later, hence check the
6060 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6061 !list_empty_careful(&ctx
->poll_list
)) {
6062 finish_wait(&ctx
->sqo_wait
, &wait
);
6066 /* Tell userspace we may need a wakeup call */
6067 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6068 /* make sure to read SQ tail after writing flags */
6071 to_submit
= io_sqring_entries(ctx
);
6072 if (!to_submit
|| ret
== -EBUSY
) {
6073 if (kthread_should_park()) {
6074 finish_wait(&ctx
->sqo_wait
, &wait
);
6077 if (current
->task_works
) {
6079 finish_wait(&ctx
->sqo_wait
, &wait
);
6082 if (signal_pending(current
))
6083 flush_signals(current
);
6085 finish_wait(&ctx
->sqo_wait
, &wait
);
6087 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6091 finish_wait(&ctx
->sqo_wait
, &wait
);
6093 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6096 mutex_lock(&ctx
->uring_lock
);
6097 if (likely(!percpu_ref_is_dying(&ctx
->refs
)))
6098 ret
= io_submit_sqes(ctx
, to_submit
, NULL
, -1);
6099 mutex_unlock(&ctx
->uring_lock
);
6100 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6103 if (current
->task_works
)
6107 io_sq_thread_drop_mm(ctx
);
6108 revert_creds(old_cred
);
6115 struct io_wait_queue
{
6116 struct wait_queue_entry wq
;
6117 struct io_ring_ctx
*ctx
;
6119 unsigned nr_timeouts
;
6122 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
6124 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6127 * Wake up if we have enough events, or if a timeout occurred since we
6128 * started waiting. For timeouts, we always want to return to userspace,
6129 * regardless of event count.
6131 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
6132 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6135 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6136 int wake_flags
, void *key
)
6138 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6141 /* use noflush == true, as we can't safely rely on locking context */
6142 if (!io_should_wake(iowq
, true))
6145 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6149 * Wait until events become available, if we don't already have some. The
6150 * application must reap them itself, as they reside on the shared cq ring.
6152 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6153 const sigset_t __user
*sig
, size_t sigsz
)
6155 struct io_wait_queue iowq
= {
6158 .func
= io_wake_function
,
6159 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6162 .to_wait
= min_events
,
6164 struct io_rings
*rings
= ctx
->rings
;
6168 if (io_cqring_events(ctx
, false) >= min_events
)
6170 if (!current
->task_works
)
6176 #ifdef CONFIG_COMPAT
6177 if (in_compat_syscall())
6178 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6182 ret
= set_user_sigmask(sig
, sigsz
);
6188 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6189 trace_io_uring_cqring_wait(ctx
, min_events
);
6191 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
6192 TASK_INTERRUPTIBLE
);
6193 if (current
->task_works
)
6195 if (io_should_wake(&iowq
, false))
6198 if (signal_pending(current
)) {
6203 finish_wait(&ctx
->wait
, &iowq
.wq
);
6205 restore_saved_sigmask_unless(ret
== -EINTR
);
6207 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
6210 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6212 #if defined(CONFIG_UNIX)
6213 if (ctx
->ring_sock
) {
6214 struct sock
*sock
= ctx
->ring_sock
->sk
;
6215 struct sk_buff
*skb
;
6217 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
6223 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6226 file
= io_file_from_index(ctx
, i
);
6233 static void io_file_ref_kill(struct percpu_ref
*ref
)
6235 struct fixed_file_data
*data
;
6237 data
= container_of(ref
, struct fixed_file_data
, refs
);
6238 complete(&data
->done
);
6241 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6243 struct fixed_file_data
*data
= ctx
->file_data
;
6244 struct fixed_file_ref_node
*ref_node
= NULL
;
6245 unsigned nr_tables
, i
;
6250 spin_lock(&data
->lock
);
6251 if (!list_empty(&data
->ref_list
))
6252 ref_node
= list_first_entry(&data
->ref_list
,
6253 struct fixed_file_ref_node
, node
);
6254 spin_unlock(&data
->lock
);
6256 percpu_ref_kill(&ref_node
->refs
);
6258 percpu_ref_kill(&data
->refs
);
6260 /* wait for all refs nodes to complete */
6261 flush_delayed_work(&ctx
->file_put_work
);
6262 wait_for_completion(&data
->done
);
6264 __io_sqe_files_unregister(ctx
);
6265 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
6266 for (i
= 0; i
< nr_tables
; i
++)
6267 kfree(data
->table
[i
].files
);
6269 percpu_ref_exit(&data
->refs
);
6271 ctx
->file_data
= NULL
;
6272 ctx
->nr_user_files
= 0;
6276 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
6278 if (ctx
->sqo_thread
) {
6279 wait_for_completion(&ctx
->sq_thread_comp
);
6281 * The park is a bit of a work-around, without it we get
6282 * warning spews on shutdown with SQPOLL set and affinity
6283 * set to a single CPU.
6285 kthread_park(ctx
->sqo_thread
);
6286 kthread_stop(ctx
->sqo_thread
);
6287 ctx
->sqo_thread
= NULL
;
6291 static void io_finish_async(struct io_ring_ctx
*ctx
)
6293 io_sq_thread_stop(ctx
);
6296 io_wq_destroy(ctx
->io_wq
);
6301 #if defined(CONFIG_UNIX)
6303 * Ensure the UNIX gc is aware of our file set, so we are certain that
6304 * the io_uring can be safely unregistered on process exit, even if we have
6305 * loops in the file referencing.
6307 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
6309 struct sock
*sk
= ctx
->ring_sock
->sk
;
6310 struct scm_fp_list
*fpl
;
6311 struct sk_buff
*skb
;
6314 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
6318 skb
= alloc_skb(0, GFP_KERNEL
);
6327 fpl
->user
= get_uid(ctx
->user
);
6328 for (i
= 0; i
< nr
; i
++) {
6329 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
6333 fpl
->fp
[nr_files
] = get_file(file
);
6334 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
6339 fpl
->max
= SCM_MAX_FD
;
6340 fpl
->count
= nr_files
;
6341 UNIXCB(skb
).fp
= fpl
;
6342 skb
->destructor
= unix_destruct_scm
;
6343 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
6344 skb_queue_head(&sk
->sk_receive_queue
, skb
);
6346 for (i
= 0; i
< nr_files
; i
++)
6357 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
6358 * causes regular reference counting to break down. We rely on the UNIX
6359 * garbage collection to take care of this problem for us.
6361 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6363 unsigned left
, total
;
6367 left
= ctx
->nr_user_files
;
6369 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
6371 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
6375 total
+= this_files
;
6381 while (total
< ctx
->nr_user_files
) {
6382 struct file
*file
= io_file_from_index(ctx
, total
);
6392 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6398 static int io_sqe_alloc_file_tables(struct io_ring_ctx
*ctx
, unsigned nr_tables
,
6403 for (i
= 0; i
< nr_tables
; i
++) {
6404 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6405 unsigned this_files
;
6407 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
6408 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
6412 nr_files
-= this_files
;
6418 for (i
= 0; i
< nr_tables
; i
++) {
6419 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6420 kfree(table
->files
);
6425 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
6427 #if defined(CONFIG_UNIX)
6428 struct sock
*sock
= ctx
->ring_sock
->sk
;
6429 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
6430 struct sk_buff
*skb
;
6433 __skb_queue_head_init(&list
);
6436 * Find the skb that holds this file in its SCM_RIGHTS. When found,
6437 * remove this entry and rearrange the file array.
6439 skb
= skb_dequeue(head
);
6441 struct scm_fp_list
*fp
;
6443 fp
= UNIXCB(skb
).fp
;
6444 for (i
= 0; i
< fp
->count
; i
++) {
6447 if (fp
->fp
[i
] != file
)
6450 unix_notinflight(fp
->user
, fp
->fp
[i
]);
6451 left
= fp
->count
- 1 - i
;
6453 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
6454 left
* sizeof(struct file
*));
6461 __skb_queue_tail(&list
, skb
);
6471 __skb_queue_tail(&list
, skb
);
6473 skb
= skb_dequeue(head
);
6476 if (skb_peek(&list
)) {
6477 spin_lock_irq(&head
->lock
);
6478 while ((skb
= __skb_dequeue(&list
)) != NULL
)
6479 __skb_queue_tail(head
, skb
);
6480 spin_unlock_irq(&head
->lock
);
6487 struct io_file_put
{
6488 struct list_head list
;
6492 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
6494 struct fixed_file_data
*file_data
= ref_node
->file_data
;
6495 struct io_ring_ctx
*ctx
= file_data
->ctx
;
6496 struct io_file_put
*pfile
, *tmp
;
6498 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
6499 list_del(&pfile
->list
);
6500 io_ring_file_put(ctx
, pfile
->file
);
6504 spin_lock(&file_data
->lock
);
6505 list_del(&ref_node
->node
);
6506 spin_unlock(&file_data
->lock
);
6508 percpu_ref_exit(&ref_node
->refs
);
6510 percpu_ref_put(&file_data
->refs
);
6513 static void io_file_put_work(struct work_struct
*work
)
6515 struct io_ring_ctx
*ctx
;
6516 struct llist_node
*node
;
6518 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
6519 node
= llist_del_all(&ctx
->file_put_llist
);
6522 struct fixed_file_ref_node
*ref_node
;
6523 struct llist_node
*next
= node
->next
;
6525 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
6526 __io_file_put_work(ref_node
);
6531 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
6533 struct fixed_file_ref_node
*ref_node
;
6534 struct io_ring_ctx
*ctx
;
6538 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
6539 ctx
= ref_node
->file_data
->ctx
;
6541 if (percpu_ref_is_dying(&ctx
->file_data
->refs
))
6544 first_add
= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
6546 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
6548 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
6551 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
6552 struct io_ring_ctx
*ctx
)
6554 struct fixed_file_ref_node
*ref_node
;
6556 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
6558 return ERR_PTR(-ENOMEM
);
6560 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
6563 return ERR_PTR(-ENOMEM
);
6565 INIT_LIST_HEAD(&ref_node
->node
);
6566 INIT_LIST_HEAD(&ref_node
->file_list
);
6567 ref_node
->file_data
= ctx
->file_data
;
6571 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
6573 percpu_ref_exit(&ref_node
->refs
);
6577 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
6580 __s32 __user
*fds
= (__s32 __user
*) arg
;
6585 struct fixed_file_ref_node
*ref_node
;
6591 if (nr_args
> IORING_MAX_FIXED_FILES
)
6594 ctx
->file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
6595 if (!ctx
->file_data
)
6597 ctx
->file_data
->ctx
= ctx
;
6598 init_completion(&ctx
->file_data
->done
);
6599 INIT_LIST_HEAD(&ctx
->file_data
->ref_list
);
6600 spin_lock_init(&ctx
->file_data
->lock
);
6602 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
6603 ctx
->file_data
->table
= kcalloc(nr_tables
,
6604 sizeof(struct fixed_file_table
),
6606 if (!ctx
->file_data
->table
) {
6607 kfree(ctx
->file_data
);
6608 ctx
->file_data
= NULL
;
6612 if (percpu_ref_init(&ctx
->file_data
->refs
, io_file_ref_kill
,
6613 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
)) {
6614 kfree(ctx
->file_data
->table
);
6615 kfree(ctx
->file_data
);
6616 ctx
->file_data
= NULL
;
6620 if (io_sqe_alloc_file_tables(ctx
, nr_tables
, nr_args
)) {
6621 percpu_ref_exit(&ctx
->file_data
->refs
);
6622 kfree(ctx
->file_data
->table
);
6623 kfree(ctx
->file_data
);
6624 ctx
->file_data
= NULL
;
6628 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
6629 struct fixed_file_table
*table
;
6633 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
)))
6635 /* allow sparse sets */
6641 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
6642 index
= i
& IORING_FILE_TABLE_MASK
;
6650 * Don't allow io_uring instances to be registered. If UNIX
6651 * isn't enabled, then this causes a reference cycle and this
6652 * instance can never get freed. If UNIX is enabled we'll
6653 * handle it just fine, but there's still no point in allowing
6654 * a ring fd as it doesn't support regular read/write anyway.
6656 if (file
->f_op
== &io_uring_fops
) {
6661 table
->files
[index
] = file
;
6665 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6666 file
= io_file_from_index(ctx
, i
);
6670 for (i
= 0; i
< nr_tables
; i
++)
6671 kfree(ctx
->file_data
->table
[i
].files
);
6673 kfree(ctx
->file_data
->table
);
6674 kfree(ctx
->file_data
);
6675 ctx
->file_data
= NULL
;
6676 ctx
->nr_user_files
= 0;
6680 ret
= io_sqe_files_scm(ctx
);
6682 io_sqe_files_unregister(ctx
);
6686 ref_node
= alloc_fixed_file_ref_node(ctx
);
6687 if (IS_ERR(ref_node
)) {
6688 io_sqe_files_unregister(ctx
);
6689 return PTR_ERR(ref_node
);
6692 ctx
->file_data
->cur_refs
= &ref_node
->refs
;
6693 spin_lock(&ctx
->file_data
->lock
);
6694 list_add(&ref_node
->node
, &ctx
->file_data
->ref_list
);
6695 spin_unlock(&ctx
->file_data
->lock
);
6696 percpu_ref_get(&ctx
->file_data
->refs
);
6700 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
6703 #if defined(CONFIG_UNIX)
6704 struct sock
*sock
= ctx
->ring_sock
->sk
;
6705 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
6706 struct sk_buff
*skb
;
6709 * See if we can merge this file into an existing skb SCM_RIGHTS
6710 * file set. If there's no room, fall back to allocating a new skb
6711 * and filling it in.
6713 spin_lock_irq(&head
->lock
);
6714 skb
= skb_peek(head
);
6716 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
6718 if (fpl
->count
< SCM_MAX_FD
) {
6719 __skb_unlink(skb
, head
);
6720 spin_unlock_irq(&head
->lock
);
6721 fpl
->fp
[fpl
->count
] = get_file(file
);
6722 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
6724 spin_lock_irq(&head
->lock
);
6725 __skb_queue_head(head
, skb
);
6730 spin_unlock_irq(&head
->lock
);
6737 return __io_sqe_files_scm(ctx
, 1, index
);
6743 static int io_queue_file_removal(struct fixed_file_data
*data
,
6746 struct io_file_put
*pfile
;
6747 struct percpu_ref
*refs
= data
->cur_refs
;
6748 struct fixed_file_ref_node
*ref_node
;
6750 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
6754 ref_node
= container_of(refs
, struct fixed_file_ref_node
, refs
);
6756 list_add(&pfile
->list
, &ref_node
->file_list
);
6761 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
6762 struct io_uring_files_update
*up
,
6765 struct fixed_file_data
*data
= ctx
->file_data
;
6766 struct fixed_file_ref_node
*ref_node
;
6771 bool needs_switch
= false;
6773 if (check_add_overflow(up
->offset
, nr_args
, &done
))
6775 if (done
> ctx
->nr_user_files
)
6778 ref_node
= alloc_fixed_file_ref_node(ctx
);
6779 if (IS_ERR(ref_node
))
6780 return PTR_ERR(ref_node
);
6783 fds
= u64_to_user_ptr(up
->fds
);
6785 struct fixed_file_table
*table
;
6789 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
6793 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
6794 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
6795 index
= i
& IORING_FILE_TABLE_MASK
;
6796 if (table
->files
[index
]) {
6797 file
= io_file_from_index(ctx
, index
);
6798 err
= io_queue_file_removal(data
, file
);
6801 table
->files
[index
] = NULL
;
6802 needs_switch
= true;
6811 * Don't allow io_uring instances to be registered. If
6812 * UNIX isn't enabled, then this causes a reference
6813 * cycle and this instance can never get freed. If UNIX
6814 * is enabled we'll handle it just fine, but there's
6815 * still no point in allowing a ring fd as it doesn't
6816 * support regular read/write anyway.
6818 if (file
->f_op
== &io_uring_fops
) {
6823 table
->files
[index
] = file
;
6824 err
= io_sqe_file_register(ctx
, file
, i
);
6834 percpu_ref_kill(data
->cur_refs
);
6835 spin_lock(&data
->lock
);
6836 list_add(&ref_node
->node
, &data
->ref_list
);
6837 data
->cur_refs
= &ref_node
->refs
;
6838 spin_unlock(&data
->lock
);
6839 percpu_ref_get(&ctx
->file_data
->refs
);
6841 destroy_fixed_file_ref_node(ref_node
);
6843 return done
? done
: err
;
6846 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
6849 struct io_uring_files_update up
;
6851 if (!ctx
->file_data
)
6855 if (copy_from_user(&up
, arg
, sizeof(up
)))
6860 return __io_sqe_files_update(ctx
, &up
, nr_args
);
6863 static void io_free_work(struct io_wq_work
*work
)
6865 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
6867 /* Consider that io_steal_work() relies on this ref */
6871 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
6872 struct io_uring_params
*p
)
6874 struct io_wq_data data
;
6876 struct io_ring_ctx
*ctx_attach
;
6877 unsigned int concurrency
;
6880 data
.user
= ctx
->user
;
6881 data
.free_work
= io_free_work
;
6883 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
6884 /* Do QD, or 4 * CPUS, whatever is smallest */
6885 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
6887 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
6888 if (IS_ERR(ctx
->io_wq
)) {
6889 ret
= PTR_ERR(ctx
->io_wq
);
6895 f
= fdget(p
->wq_fd
);
6899 if (f
.file
->f_op
!= &io_uring_fops
) {
6904 ctx_attach
= f
.file
->private_data
;
6905 /* @io_wq is protected by holding the fd */
6906 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
6911 ctx
->io_wq
= ctx_attach
->io_wq
;
6917 static int io_sq_offload_start(struct io_ring_ctx
*ctx
,
6918 struct io_uring_params
*p
)
6922 mmgrab(current
->mm
);
6923 ctx
->sqo_mm
= current
->mm
;
6925 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
6927 if (!capable(CAP_SYS_ADMIN
))
6930 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
6931 if (!ctx
->sq_thread_idle
)
6932 ctx
->sq_thread_idle
= HZ
;
6934 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
6935 int cpu
= p
->sq_thread_cpu
;
6938 if (cpu
>= nr_cpu_ids
)
6940 if (!cpu_online(cpu
))
6943 ctx
->sqo_thread
= kthread_create_on_cpu(io_sq_thread
,
6947 ctx
->sqo_thread
= kthread_create(io_sq_thread
, ctx
,
6950 if (IS_ERR(ctx
->sqo_thread
)) {
6951 ret
= PTR_ERR(ctx
->sqo_thread
);
6952 ctx
->sqo_thread
= NULL
;
6955 wake_up_process(ctx
->sqo_thread
);
6956 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
6957 /* Can't have SQ_AFF without SQPOLL */
6962 ret
= io_init_wq_offload(ctx
, p
);
6968 io_finish_async(ctx
);
6969 mmdrop(ctx
->sqo_mm
);
6974 static void io_unaccount_mem(struct user_struct
*user
, unsigned long nr_pages
)
6976 atomic_long_sub(nr_pages
, &user
->locked_vm
);
6979 static int io_account_mem(struct user_struct
*user
, unsigned long nr_pages
)
6981 unsigned long page_limit
, cur_pages
, new_pages
;
6983 /* Don't allow more pages than we can safely lock */
6984 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
6987 cur_pages
= atomic_long_read(&user
->locked_vm
);
6988 new_pages
= cur_pages
+ nr_pages
;
6989 if (new_pages
> page_limit
)
6991 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
6992 new_pages
) != cur_pages
);
6997 static void io_mem_free(void *ptr
)
7004 page
= virt_to_head_page(ptr
);
7005 if (put_page_testzero(page
))
7006 free_compound_page(page
);
7009 static void *io_mem_alloc(size_t size
)
7011 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
7014 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
7017 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
7020 struct io_rings
*rings
;
7021 size_t off
, sq_array_size
;
7023 off
= struct_size(rings
, cqes
, cq_entries
);
7024 if (off
== SIZE_MAX
)
7028 off
= ALIGN(off
, SMP_CACHE_BYTES
);
7033 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
7034 if (sq_array_size
== SIZE_MAX
)
7037 if (check_add_overflow(off
, sq_array_size
, &off
))
7046 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
7050 pages
= (size_t)1 << get_order(
7051 rings_size(sq_entries
, cq_entries
, NULL
));
7052 pages
+= (size_t)1 << get_order(
7053 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
7058 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
7062 if (!ctx
->user_bufs
)
7065 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7066 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7068 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
7069 unpin_user_page(imu
->bvec
[j
].bv_page
);
7071 if (ctx
->account_mem
)
7072 io_unaccount_mem(ctx
->user
, imu
->nr_bvecs
);
7077 kfree(ctx
->user_bufs
);
7078 ctx
->user_bufs
= NULL
;
7079 ctx
->nr_user_bufs
= 0;
7083 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
7084 void __user
*arg
, unsigned index
)
7086 struct iovec __user
*src
;
7088 #ifdef CONFIG_COMPAT
7090 struct compat_iovec __user
*ciovs
;
7091 struct compat_iovec ciov
;
7093 ciovs
= (struct compat_iovec __user
*) arg
;
7094 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
7097 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
7098 dst
->iov_len
= ciov
.iov_len
;
7102 src
= (struct iovec __user
*) arg
;
7103 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
7108 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7111 struct vm_area_struct
**vmas
= NULL
;
7112 struct page
**pages
= NULL
;
7113 int i
, j
, got_pages
= 0;
7118 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
7121 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
7123 if (!ctx
->user_bufs
)
7126 for (i
= 0; i
< nr_args
; i
++) {
7127 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7128 unsigned long off
, start
, end
, ubuf
;
7133 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
7138 * Don't impose further limits on the size and buffer
7139 * constraints here, we'll -EINVAL later when IO is
7140 * submitted if they are wrong.
7143 if (!iov
.iov_base
|| !iov
.iov_len
)
7146 /* arbitrary limit, but we need something */
7147 if (iov
.iov_len
> SZ_1G
)
7150 ubuf
= (unsigned long) iov
.iov_base
;
7151 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
7152 start
= ubuf
>> PAGE_SHIFT
;
7153 nr_pages
= end
- start
;
7155 if (ctx
->account_mem
) {
7156 ret
= io_account_mem(ctx
->user
, nr_pages
);
7162 if (!pages
|| nr_pages
> got_pages
) {
7165 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
7167 vmas
= kvmalloc_array(nr_pages
,
7168 sizeof(struct vm_area_struct
*),
7170 if (!pages
|| !vmas
) {
7172 if (ctx
->account_mem
)
7173 io_unaccount_mem(ctx
->user
, nr_pages
);
7176 got_pages
= nr_pages
;
7179 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
7183 if (ctx
->account_mem
)
7184 io_unaccount_mem(ctx
->user
, nr_pages
);
7189 down_read(¤t
->mm
->mmap_sem
);
7190 pret
= pin_user_pages(ubuf
, nr_pages
,
7191 FOLL_WRITE
| FOLL_LONGTERM
,
7193 if (pret
== nr_pages
) {
7194 /* don't support file backed memory */
7195 for (j
= 0; j
< nr_pages
; j
++) {
7196 struct vm_area_struct
*vma
= vmas
[j
];
7199 !is_file_hugepages(vma
->vm_file
)) {
7205 ret
= pret
< 0 ? pret
: -EFAULT
;
7207 up_read(¤t
->mm
->mmap_sem
);
7210 * if we did partial map, or found file backed vmas,
7211 * release any pages we did get
7214 unpin_user_pages(pages
, pret
);
7215 if (ctx
->account_mem
)
7216 io_unaccount_mem(ctx
->user
, nr_pages
);
7221 off
= ubuf
& ~PAGE_MASK
;
7223 for (j
= 0; j
< nr_pages
; j
++) {
7226 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
7227 imu
->bvec
[j
].bv_page
= pages
[j
];
7228 imu
->bvec
[j
].bv_len
= vec_len
;
7229 imu
->bvec
[j
].bv_offset
= off
;
7233 /* store original address for later verification */
7235 imu
->len
= iov
.iov_len
;
7236 imu
->nr_bvecs
= nr_pages
;
7238 ctx
->nr_user_bufs
++;
7246 io_sqe_buffer_unregister(ctx
);
7250 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
7252 __s32 __user
*fds
= arg
;
7258 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
7261 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
7262 if (IS_ERR(ctx
->cq_ev_fd
)) {
7263 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
7264 ctx
->cq_ev_fd
= NULL
;
7271 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
7273 if (ctx
->cq_ev_fd
) {
7274 eventfd_ctx_put(ctx
->cq_ev_fd
);
7275 ctx
->cq_ev_fd
= NULL
;
7282 static int __io_destroy_buffers(int id
, void *p
, void *data
)
7284 struct io_ring_ctx
*ctx
= data
;
7285 struct io_buffer
*buf
= p
;
7287 __io_remove_buffers(ctx
, buf
, id
, -1U);
7291 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
7293 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
7294 idr_destroy(&ctx
->io_buffer_idr
);
7297 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
7299 io_finish_async(ctx
);
7301 mmdrop(ctx
->sqo_mm
);
7303 io_iopoll_reap_events(ctx
);
7304 io_sqe_buffer_unregister(ctx
);
7305 io_sqe_files_unregister(ctx
);
7306 io_eventfd_unregister(ctx
);
7307 io_destroy_buffers(ctx
);
7308 idr_destroy(&ctx
->personality_idr
);
7310 #if defined(CONFIG_UNIX)
7311 if (ctx
->ring_sock
) {
7312 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
7313 sock_release(ctx
->ring_sock
);
7317 io_mem_free(ctx
->rings
);
7318 io_mem_free(ctx
->sq_sqes
);
7320 percpu_ref_exit(&ctx
->refs
);
7321 if (ctx
->account_mem
)
7322 io_unaccount_mem(ctx
->user
,
7323 ring_pages(ctx
->sq_entries
, ctx
->cq_entries
));
7324 free_uid(ctx
->user
);
7325 put_cred(ctx
->creds
);
7326 kfree(ctx
->cancel_hash
);
7327 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
7331 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
7333 struct io_ring_ctx
*ctx
= file
->private_data
;
7336 poll_wait(file
, &ctx
->cq_wait
, wait
);
7338 * synchronizes with barrier from wq_has_sleeper call in
7342 if (READ_ONCE(ctx
->rings
->sq
.tail
) - ctx
->cached_sq_head
!=
7343 ctx
->rings
->sq_ring_entries
)
7344 mask
|= EPOLLOUT
| EPOLLWRNORM
;
7345 if (io_cqring_events(ctx
, false))
7346 mask
|= EPOLLIN
| EPOLLRDNORM
;
7351 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
7353 struct io_ring_ctx
*ctx
= file
->private_data
;
7355 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
7358 static int io_remove_personalities(int id
, void *p
, void *data
)
7360 struct io_ring_ctx
*ctx
= data
;
7361 const struct cred
*cred
;
7363 cred
= idr_remove(&ctx
->personality_idr
, id
);
7369 static void io_ring_exit_work(struct work_struct
*work
)
7371 struct io_ring_ctx
*ctx
;
7373 ctx
= container_of(work
, struct io_ring_ctx
, exit_work
);
7375 io_cqring_overflow_flush(ctx
, true);
7377 wait_for_completion(&ctx
->ref_comp
);
7378 io_ring_ctx_free(ctx
);
7381 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
7383 mutex_lock(&ctx
->uring_lock
);
7384 percpu_ref_kill(&ctx
->refs
);
7385 mutex_unlock(&ctx
->uring_lock
);
7387 io_kill_timeouts(ctx
);
7388 io_poll_remove_all(ctx
);
7391 io_wq_cancel_all(ctx
->io_wq
);
7393 io_iopoll_reap_events(ctx
);
7394 /* if we failed setting up the ctx, we might not have any rings */
7396 io_cqring_overflow_flush(ctx
, true);
7397 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
7398 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
7399 queue_work(system_wq
, &ctx
->exit_work
);
7402 static int io_uring_release(struct inode
*inode
, struct file
*file
)
7404 struct io_ring_ctx
*ctx
= file
->private_data
;
7406 file
->private_data
= NULL
;
7407 io_ring_ctx_wait_and_kill(ctx
);
7411 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
7412 struct files_struct
*files
)
7414 while (!list_empty_careful(&ctx
->inflight_list
)) {
7415 struct io_kiocb
*cancel_req
= NULL
, *req
;
7418 spin_lock_irq(&ctx
->inflight_lock
);
7419 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
7420 if (req
->work
.files
!= files
)
7422 /* req is being completed, ignore */
7423 if (!refcount_inc_not_zero(&req
->refs
))
7429 prepare_to_wait(&ctx
->inflight_wait
, &wait
,
7430 TASK_UNINTERRUPTIBLE
);
7431 spin_unlock_irq(&ctx
->inflight_lock
);
7433 /* We need to keep going until we don't find a matching req */
7437 if (cancel_req
->flags
& REQ_F_OVERFLOW
) {
7438 spin_lock_irq(&ctx
->completion_lock
);
7439 list_del(&cancel_req
->list
);
7440 cancel_req
->flags
&= ~REQ_F_OVERFLOW
;
7441 if (list_empty(&ctx
->cq_overflow_list
)) {
7442 clear_bit(0, &ctx
->sq_check_overflow
);
7443 clear_bit(0, &ctx
->cq_check_overflow
);
7445 spin_unlock_irq(&ctx
->completion_lock
);
7447 WRITE_ONCE(ctx
->rings
->cq_overflow
,
7448 atomic_inc_return(&ctx
->cached_cq_overflow
));
7451 * Put inflight ref and overflow ref. If that's
7452 * all we had, then we're done with this request.
7454 if (refcount_sub_and_test(2, &cancel_req
->refs
)) {
7455 io_free_req(cancel_req
);
7456 finish_wait(&ctx
->inflight_wait
, &wait
);
7460 io_wq_cancel_work(ctx
->io_wq
, &cancel_req
->work
);
7461 io_put_req(cancel_req
);
7465 finish_wait(&ctx
->inflight_wait
, &wait
);
7469 static int io_uring_flush(struct file
*file
, void *data
)
7471 struct io_ring_ctx
*ctx
= file
->private_data
;
7473 io_uring_cancel_files(ctx
, data
);
7476 * If the task is going away, cancel work it may have pending
7478 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
))
7479 io_wq_cancel_pid(ctx
->io_wq
, task_pid_vnr(current
));
7484 static void *io_uring_validate_mmap_request(struct file
*file
,
7485 loff_t pgoff
, size_t sz
)
7487 struct io_ring_ctx
*ctx
= file
->private_data
;
7488 loff_t offset
= pgoff
<< PAGE_SHIFT
;
7493 case IORING_OFF_SQ_RING
:
7494 case IORING_OFF_CQ_RING
:
7497 case IORING_OFF_SQES
:
7501 return ERR_PTR(-EINVAL
);
7504 page
= virt_to_head_page(ptr
);
7505 if (sz
> page_size(page
))
7506 return ERR_PTR(-EINVAL
);
7513 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
7515 size_t sz
= vma
->vm_end
- vma
->vm_start
;
7519 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
7521 return PTR_ERR(ptr
);
7523 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
7524 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
7527 #else /* !CONFIG_MMU */
7529 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
7531 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
7534 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
7536 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
7539 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
7540 unsigned long addr
, unsigned long len
,
7541 unsigned long pgoff
, unsigned long flags
)
7545 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
7547 return PTR_ERR(ptr
);
7549 return (unsigned long) ptr
;
7552 #endif /* !CONFIG_MMU */
7554 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
7555 u32
, min_complete
, u32
, flags
, const sigset_t __user
*, sig
,
7558 struct io_ring_ctx
*ctx
;
7563 if (current
->task_works
)
7566 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
))
7574 if (f
.file
->f_op
!= &io_uring_fops
)
7578 ctx
= f
.file
->private_data
;
7579 if (!percpu_ref_tryget(&ctx
->refs
))
7583 * For SQ polling, the thread will do all submissions and completions.
7584 * Just return the requested submit count, and wake the thread if
7588 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7589 if (!list_empty_careful(&ctx
->cq_overflow_list
))
7590 io_cqring_overflow_flush(ctx
, false);
7591 if (flags
& IORING_ENTER_SQ_WAKEUP
)
7592 wake_up(&ctx
->sqo_wait
);
7593 submitted
= to_submit
;
7594 } else if (to_submit
) {
7595 mutex_lock(&ctx
->uring_lock
);
7596 submitted
= io_submit_sqes(ctx
, to_submit
, f
.file
, fd
);
7597 mutex_unlock(&ctx
->uring_lock
);
7599 if (submitted
!= to_submit
)
7602 if (flags
& IORING_ENTER_GETEVENTS
) {
7603 unsigned nr_events
= 0;
7605 min_complete
= min(min_complete
, ctx
->cq_entries
);
7608 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
7609 * space applications don't need to do io completion events
7610 * polling again, they can rely on io_sq_thread to do polling
7611 * work, which can reduce cpu usage and uring_lock contention.
7613 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
7614 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
7615 ret
= io_iopoll_check(ctx
, &nr_events
, min_complete
);
7617 ret
= io_cqring_wait(ctx
, min_complete
, sig
, sigsz
);
7622 percpu_ref_put(&ctx
->refs
);
7625 return submitted
? submitted
: ret
;
7628 #ifdef CONFIG_PROC_FS
7629 static int io_uring_show_cred(int id
, void *p
, void *data
)
7631 const struct cred
*cred
= p
;
7632 struct seq_file
*m
= data
;
7633 struct user_namespace
*uns
= seq_user_ns(m
);
7634 struct group_info
*gi
;
7639 seq_printf(m
, "%5d\n", id
);
7640 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
7641 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
7642 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
7643 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
7644 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
7645 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
7646 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
7647 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
7648 seq_puts(m
, "\n\tGroups:\t");
7649 gi
= cred
->group_info
;
7650 for (g
= 0; g
< gi
->ngroups
; g
++) {
7651 seq_put_decimal_ull(m
, g
? " " : "",
7652 from_kgid_munged(uns
, gi
->gid
[g
]));
7654 seq_puts(m
, "\n\tCapEff:\t");
7655 cap
= cred
->cap_effective
;
7656 CAP_FOR_EACH_U32(__capi
)
7657 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
7662 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
7666 mutex_lock(&ctx
->uring_lock
);
7667 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
7668 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7669 struct fixed_file_table
*table
;
7672 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7673 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
7675 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
7677 seq_printf(m
, "%5u: <none>\n", i
);
7679 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
7680 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7681 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
7683 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
7684 (unsigned int) buf
->len
);
7686 if (!idr_is_empty(&ctx
->personality_idr
)) {
7687 seq_printf(m
, "Personalities:\n");
7688 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
7690 seq_printf(m
, "PollList:\n");
7691 spin_lock_irq(&ctx
->completion_lock
);
7692 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
7693 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
7694 struct io_kiocb
*req
;
7696 hlist_for_each_entry(req
, list
, hash_node
)
7697 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
7698 req
->task
->task_works
!= NULL
);
7700 spin_unlock_irq(&ctx
->completion_lock
);
7701 mutex_unlock(&ctx
->uring_lock
);
7704 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
7706 struct io_ring_ctx
*ctx
= f
->private_data
;
7708 if (percpu_ref_tryget(&ctx
->refs
)) {
7709 __io_uring_show_fdinfo(ctx
, m
);
7710 percpu_ref_put(&ctx
->refs
);
7715 static const struct file_operations io_uring_fops
= {
7716 .release
= io_uring_release
,
7717 .flush
= io_uring_flush
,
7718 .mmap
= io_uring_mmap
,
7720 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
7721 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
7723 .poll
= io_uring_poll
,
7724 .fasync
= io_uring_fasync
,
7725 #ifdef CONFIG_PROC_FS
7726 .show_fdinfo
= io_uring_show_fdinfo
,
7730 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
7731 struct io_uring_params
*p
)
7733 struct io_rings
*rings
;
7734 size_t size
, sq_array_offset
;
7736 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
7737 if (size
== SIZE_MAX
)
7740 rings
= io_mem_alloc(size
);
7745 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
7746 rings
->sq_ring_mask
= p
->sq_entries
- 1;
7747 rings
->cq_ring_mask
= p
->cq_entries
- 1;
7748 rings
->sq_ring_entries
= p
->sq_entries
;
7749 rings
->cq_ring_entries
= p
->cq_entries
;
7750 ctx
->sq_mask
= rings
->sq_ring_mask
;
7751 ctx
->cq_mask
= rings
->cq_ring_mask
;
7752 ctx
->sq_entries
= rings
->sq_ring_entries
;
7753 ctx
->cq_entries
= rings
->cq_ring_entries
;
7755 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
7756 if (size
== SIZE_MAX
) {
7757 io_mem_free(ctx
->rings
);
7762 ctx
->sq_sqes
= io_mem_alloc(size
);
7763 if (!ctx
->sq_sqes
) {
7764 io_mem_free(ctx
->rings
);
7773 * Allocate an anonymous fd, this is what constitutes the application
7774 * visible backing of an io_uring instance. The application mmaps this
7775 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
7776 * we have to tie this fd to a socket for file garbage collection purposes.
7778 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
7783 #if defined(CONFIG_UNIX)
7784 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
7790 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
7794 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
7795 O_RDWR
| O_CLOEXEC
);
7798 ret
= PTR_ERR(file
);
7802 #if defined(CONFIG_UNIX)
7803 ctx
->ring_sock
->file
= file
;
7805 fd_install(ret
, file
);
7808 #if defined(CONFIG_UNIX)
7809 sock_release(ctx
->ring_sock
);
7810 ctx
->ring_sock
= NULL
;
7815 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
7816 struct io_uring_params __user
*params
)
7818 struct user_struct
*user
= NULL
;
7819 struct io_ring_ctx
*ctx
;
7825 if (entries
> IORING_MAX_ENTRIES
) {
7826 if (!(p
->flags
& IORING_SETUP_CLAMP
))
7828 entries
= IORING_MAX_ENTRIES
;
7832 * Use twice as many entries for the CQ ring. It's possible for the
7833 * application to drive a higher depth than the size of the SQ ring,
7834 * since the sqes are only used at submission time. This allows for
7835 * some flexibility in overcommitting a bit. If the application has
7836 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
7837 * of CQ ring entries manually.
7839 p
->sq_entries
= roundup_pow_of_two(entries
);
7840 if (p
->flags
& IORING_SETUP_CQSIZE
) {
7842 * If IORING_SETUP_CQSIZE is set, we do the same roundup
7843 * to a power-of-two, if it isn't already. We do NOT impose
7844 * any cq vs sq ring sizing.
7846 if (p
->cq_entries
< p
->sq_entries
)
7848 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
7849 if (!(p
->flags
& IORING_SETUP_CLAMP
))
7851 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
7853 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
7855 p
->cq_entries
= 2 * p
->sq_entries
;
7858 user
= get_uid(current_user());
7859 account_mem
= !capable(CAP_IPC_LOCK
);
7862 ret
= io_account_mem(user
,
7863 ring_pages(p
->sq_entries
, p
->cq_entries
));
7870 ctx
= io_ring_ctx_alloc(p
);
7873 io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
7878 ctx
->compat
= in_compat_syscall();
7879 ctx
->account_mem
= account_mem
;
7881 ctx
->creds
= get_current_cred();
7883 ret
= io_allocate_scq_urings(ctx
, p
);
7887 ret
= io_sq_offload_start(ctx
, p
);
7891 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
7892 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
7893 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
7894 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
7895 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
7896 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
7897 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
7898 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
7900 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
7901 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
7902 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
7903 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
7904 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
7905 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
7906 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
7907 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
7909 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
7910 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
7911 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
;
7913 if (copy_to_user(params
, p
, sizeof(*p
))) {
7918 * Install ring fd as the very last thing, so we don't risk someone
7919 * having closed it before we finish setup
7921 ret
= io_uring_get_fd(ctx
);
7925 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
7928 io_ring_ctx_wait_and_kill(ctx
);
7933 * Sets up an aio uring context, and returns the fd. Applications asks for a
7934 * ring size, we return the actual sq/cq ring sizes (among other things) in the
7935 * params structure passed in.
7937 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
7939 struct io_uring_params p
;
7942 if (copy_from_user(&p
, params
, sizeof(p
)))
7944 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
7949 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
7950 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
7951 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
))
7954 return io_uring_create(entries
, &p
, params
);
7957 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
7958 struct io_uring_params __user
*, params
)
7960 return io_uring_setup(entries
, params
);
7963 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
7965 struct io_uring_probe
*p
;
7969 size
= struct_size(p
, ops
, nr_args
);
7970 if (size
== SIZE_MAX
)
7972 p
= kzalloc(size
, GFP_KERNEL
);
7977 if (copy_from_user(p
, arg
, size
))
7980 if (memchr_inv(p
, 0, size
))
7983 p
->last_op
= IORING_OP_LAST
- 1;
7984 if (nr_args
> IORING_OP_LAST
)
7985 nr_args
= IORING_OP_LAST
;
7987 for (i
= 0; i
< nr_args
; i
++) {
7989 if (!io_op_defs
[i
].not_supported
)
7990 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
7995 if (copy_to_user(arg
, p
, size
))
8002 static int io_register_personality(struct io_ring_ctx
*ctx
)
8004 const struct cred
*creds
= get_current_cred();
8007 id
= idr_alloc_cyclic(&ctx
->personality_idr
, (void *) creds
, 1,
8008 USHRT_MAX
, GFP_KERNEL
);
8014 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
8016 const struct cred
*old_creds
;
8018 old_creds
= idr_remove(&ctx
->personality_idr
, id
);
8020 put_cred(old_creds
);
8027 static bool io_register_op_must_quiesce(int op
)
8030 case IORING_UNREGISTER_FILES
:
8031 case IORING_REGISTER_FILES_UPDATE
:
8032 case IORING_REGISTER_PROBE
:
8033 case IORING_REGISTER_PERSONALITY
:
8034 case IORING_UNREGISTER_PERSONALITY
:
8041 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
8042 void __user
*arg
, unsigned nr_args
)
8043 __releases(ctx
->uring_lock
)
8044 __acquires(ctx
->uring_lock
)
8049 * We're inside the ring mutex, if the ref is already dying, then
8050 * someone else killed the ctx or is already going through
8051 * io_uring_register().
8053 if (percpu_ref_is_dying(&ctx
->refs
))
8056 if (io_register_op_must_quiesce(opcode
)) {
8057 percpu_ref_kill(&ctx
->refs
);
8060 * Drop uring mutex before waiting for references to exit. If
8061 * another thread is currently inside io_uring_enter() it might
8062 * need to grab the uring_lock to make progress. If we hold it
8063 * here across the drain wait, then we can deadlock. It's safe
8064 * to drop the mutex here, since no new references will come in
8065 * after we've killed the percpu ref.
8067 mutex_unlock(&ctx
->uring_lock
);
8068 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
8069 mutex_lock(&ctx
->uring_lock
);
8071 percpu_ref_resurrect(&ctx
->refs
);
8078 case IORING_REGISTER_BUFFERS
:
8079 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
8081 case IORING_UNREGISTER_BUFFERS
:
8085 ret
= io_sqe_buffer_unregister(ctx
);
8087 case IORING_REGISTER_FILES
:
8088 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
8090 case IORING_UNREGISTER_FILES
:
8094 ret
= io_sqe_files_unregister(ctx
);
8096 case IORING_REGISTER_FILES_UPDATE
:
8097 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
8099 case IORING_REGISTER_EVENTFD
:
8100 case IORING_REGISTER_EVENTFD_ASYNC
:
8104 ret
= io_eventfd_register(ctx
, arg
);
8107 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
8108 ctx
->eventfd_async
= 1;
8110 ctx
->eventfd_async
= 0;
8112 case IORING_UNREGISTER_EVENTFD
:
8116 ret
= io_eventfd_unregister(ctx
);
8118 case IORING_REGISTER_PROBE
:
8120 if (!arg
|| nr_args
> 256)
8122 ret
= io_probe(ctx
, arg
, nr_args
);
8124 case IORING_REGISTER_PERSONALITY
:
8128 ret
= io_register_personality(ctx
);
8130 case IORING_UNREGISTER_PERSONALITY
:
8134 ret
= io_unregister_personality(ctx
, nr_args
);
8141 if (io_register_op_must_quiesce(opcode
)) {
8142 /* bring the ctx back to life */
8143 percpu_ref_reinit(&ctx
->refs
);
8145 reinit_completion(&ctx
->ref_comp
);
8150 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
8151 void __user
*, arg
, unsigned int, nr_args
)
8153 struct io_ring_ctx
*ctx
;
8162 if (f
.file
->f_op
!= &io_uring_fops
)
8165 ctx
= f
.file
->private_data
;
8167 mutex_lock(&ctx
->uring_lock
);
8168 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
8169 mutex_unlock(&ctx
->uring_lock
);
8170 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
8171 ctx
->cq_ev_fd
!= NULL
, ret
);
8177 static int __init
io_uring_init(void)
8179 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
8180 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
8181 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
8184 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
8185 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
8186 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
8187 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
8188 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
8189 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
8190 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
8191 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
8192 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
8193 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
8194 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
8195 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
8196 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
8197 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
8198 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
8199 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
8200 BUILD_BUG_SQE_ELEM(28, __u16
, poll_events
);
8201 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
8202 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
8203 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
8204 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
8205 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
8206 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
8207 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
8208 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
8209 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
8210 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
8211 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
8212 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
8213 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
8215 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
8216 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
8217 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
8220 __initcall(io_uring_init
);