1 // SPDX-License-Identifier: GPL-2.0
3 * Shared application/kernel submission and completion ring pairs, for
4 * supporting fast/efficient IO.
6 * A note on the read/write ordering memory barriers that are matched between
7 * the application and kernel side.
9 * After the application reads the CQ ring tail, it must use an
10 * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
11 * before writing the tail (using smp_load_acquire to read the tail will
12 * do). It also needs a smp_mb() before updating CQ head (ordering the
13 * entry load(s) with the head store), pairing with an implicit barrier
14 * through a control-dependency in io_get_cqring (smp_store_release to
15 * store head will do). Failure to do so could lead to reading invalid
18 * Likewise, the application must use an appropriate smp_wmb() before
19 * writing the SQ tail (ordering SQ entry stores with the tail store),
20 * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
21 * to store the tail will do). And it needs a barrier ordering the SQ
22 * head load before writing new SQ entries (smp_load_acquire to read
25 * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
26 * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
27 * updating the SQ tail; a full memory barrier smp_mb() is needed
30 * Also see the examples in the liburing library:
32 * git://git.kernel.dk/liburing
34 * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
35 * from data shared between the kernel and application. This is done both
36 * for ordering purposes, but also to ensure that once a value is loaded from
37 * data that the application could potentially modify, it remains stable.
39 * Copyright (C) 2018-2019 Jens Axboe
40 * Copyright (c) 2018-2019 Christoph Hellwig
42 #include <linux/kernel.h>
43 #include <linux/init.h>
44 #include <linux/errno.h>
45 #include <linux/syscalls.h>
46 #include <linux/compat.h>
47 #include <net/compat.h>
48 #include <linux/refcount.h>
49 #include <linux/uio.h>
50 #include <linux/bits.h>
52 #include <linux/sched/signal.h>
54 #include <linux/file.h>
55 #include <linux/fdtable.h>
57 #include <linux/mman.h>
58 #include <linux/percpu.h>
59 #include <linux/slab.h>
60 #include <linux/kthread.h>
61 #include <linux/blkdev.h>
62 #include <linux/bvec.h>
63 #include <linux/net.h>
65 #include <net/af_unix.h>
67 #include <linux/anon_inodes.h>
68 #include <linux/sched/mm.h>
69 #include <linux/uaccess.h>
70 #include <linux/nospec.h>
71 #include <linux/sizes.h>
72 #include <linux/hugetlb.h>
73 #include <linux/highmem.h>
74 #include <linux/namei.h>
75 #include <linux/fsnotify.h>
76 #include <linux/fadvise.h>
77 #include <linux/eventpoll.h>
78 #include <linux/fs_struct.h>
79 #include <linux/splice.h>
80 #include <linux/task_work.h>
81 #include <linux/pagemap.h>
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 limit_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 * ->iopoll_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 iopoll_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
;
399 struct list_head list
;
403 /* NOTE: kiocb has the file as the first member, so don't do it here */
411 struct sockaddr __user
*addr
;
418 struct user_msghdr __user
*umsg
;
424 struct io_buffer
*kbuf
;
430 struct filename
*filename
;
432 unsigned long nofile
;
435 struct io_files_update
{
461 struct epoll_event event
;
465 struct file
*file_out
;
466 struct file
*file_in
;
473 struct io_provide_buf
{
487 const char __user
*filename
;
488 struct statx __user
*buffer
;
491 struct io_completion
{
493 struct list_head list
;
497 struct io_async_connect
{
498 struct sockaddr_storage address
;
501 struct io_async_msghdr
{
502 struct iovec fast_iov
[UIO_FASTIOV
];
504 struct sockaddr __user
*uaddr
;
506 struct sockaddr_storage addr
;
510 struct iovec fast_iov
[UIO_FASTIOV
];
514 struct wait_page_queue wpq
;
517 struct io_async_ctx
{
519 struct io_async_rw rw
;
520 struct io_async_msghdr msg
;
521 struct io_async_connect connect
;
522 struct io_timeout_data timeout
;
527 REQ_F_FIXED_FILE_BIT
= IOSQE_FIXED_FILE_BIT
,
528 REQ_F_IO_DRAIN_BIT
= IOSQE_IO_DRAIN_BIT
,
529 REQ_F_LINK_BIT
= IOSQE_IO_LINK_BIT
,
530 REQ_F_HARDLINK_BIT
= IOSQE_IO_HARDLINK_BIT
,
531 REQ_F_FORCE_ASYNC_BIT
= IOSQE_ASYNC_BIT
,
532 REQ_F_BUFFER_SELECT_BIT
= IOSQE_BUFFER_SELECT_BIT
,
539 REQ_F_LINK_TIMEOUT_BIT
,
541 REQ_F_COMP_LOCKED_BIT
,
542 REQ_F_NEED_CLEANUP_BIT
,
545 REQ_F_BUFFER_SELECTED_BIT
,
546 REQ_F_NO_FILE_TABLE_BIT
,
547 REQ_F_WORK_INITIALIZED_BIT
,
548 REQ_F_TASK_PINNED_BIT
,
550 /* not a real bit, just to check we're not overflowing the space */
556 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
557 /* drain existing IO first */
558 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
560 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
561 /* doesn't sever on completion < 0 */
562 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
564 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
565 /* IOSQE_BUFFER_SELECT */
566 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
569 REQ_F_LINK_HEAD
= BIT(REQ_F_LINK_HEAD_BIT
),
570 /* fail rest of links */
571 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
572 /* on inflight list */
573 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
574 /* read/write uses file position */
575 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
576 /* must not punt to workers */
577 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
578 /* has linked timeout */
579 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
581 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
582 /* completion under lock */
583 REQ_F_COMP_LOCKED
= BIT(REQ_F_COMP_LOCKED_BIT
),
585 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
586 /* in overflow list */
587 REQ_F_OVERFLOW
= BIT(REQ_F_OVERFLOW_BIT
),
588 /* already went through poll handler */
589 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
590 /* buffer already selected */
591 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
592 /* doesn't need file table for this request */
593 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
594 /* io_wq_work is initialized */
595 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
596 /* req->task is refcounted */
597 REQ_F_TASK_PINNED
= BIT(REQ_F_TASK_PINNED_BIT
),
601 struct io_poll_iocb poll
;
602 struct io_poll_iocb
*double_poll
;
606 * NOTE! Each of the iocb union members has the file pointer
607 * as the first entry in their struct definition. So you can
608 * access the file pointer through any of the sub-structs,
609 * or directly as just 'ki_filp' in this struct.
615 struct io_poll_iocb poll
;
616 struct io_accept accept
;
618 struct io_cancel cancel
;
619 struct io_timeout timeout
;
620 struct io_connect connect
;
621 struct io_sr_msg sr_msg
;
623 struct io_close close
;
624 struct io_files_update files_update
;
625 struct io_fadvise fadvise
;
626 struct io_madvise madvise
;
627 struct io_epoll epoll
;
628 struct io_splice splice
;
629 struct io_provide_buf pbuf
;
630 struct io_statx statx
;
631 /* use only after cleaning per-op data, see io_clean_op() */
632 struct io_completion
compl;
635 struct io_async_ctx
*io
;
637 /* polled IO has completed */
643 struct io_ring_ctx
*ctx
;
646 struct task_struct
*task
;
649 struct list_head link_list
;
652 * 1. used with ctx->iopoll_list with reads/writes
653 * 2. to track reqs with ->files (see io_op_def::file_table)
655 struct list_head inflight_entry
;
657 struct percpu_ref
*fixed_file_refs
;
658 struct callback_head task_work
;
659 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
660 struct hlist_node hash_node
;
661 struct async_poll
*apoll
;
662 struct io_wq_work work
;
665 struct io_defer_entry
{
666 struct list_head list
;
667 struct io_kiocb
*req
;
671 #define IO_IOPOLL_BATCH 8
673 struct io_comp_state
{
675 struct list_head list
;
676 struct io_ring_ctx
*ctx
;
679 struct io_submit_state
{
680 struct blk_plug plug
;
683 * io_kiocb alloc cache
685 void *reqs
[IO_IOPOLL_BATCH
];
686 unsigned int free_reqs
;
689 * Batch completion logic
691 struct io_comp_state comp
;
694 * File reference cache
698 unsigned int has_refs
;
699 unsigned int ios_left
;
703 /* needs req->io allocated for deferral/async */
704 unsigned async_ctx
: 1;
705 /* needs current->mm setup, does mm access */
706 unsigned needs_mm
: 1;
707 /* needs req->file assigned */
708 unsigned needs_file
: 1;
709 /* don't fail if file grab fails */
710 unsigned needs_file_no_error
: 1;
711 /* hash wq insertion if file is a regular file */
712 unsigned hash_reg_file
: 1;
713 /* unbound wq insertion if file is a non-regular file */
714 unsigned unbound_nonreg_file
: 1;
715 /* opcode is not supported by this kernel */
716 unsigned not_supported
: 1;
717 /* needs file table */
718 unsigned file_table
: 1;
720 unsigned needs_fs
: 1;
721 /* set if opcode supports polled "wait" */
723 unsigned pollout
: 1;
724 /* op supports buffer selection */
725 unsigned buffer_select
: 1;
726 unsigned needs_fsize
: 1;
729 static const struct io_op_def io_op_defs
[] = {
730 [IORING_OP_NOP
] = {},
731 [IORING_OP_READV
] = {
735 .unbound_nonreg_file
= 1,
739 [IORING_OP_WRITEV
] = {
744 .unbound_nonreg_file
= 1,
748 [IORING_OP_FSYNC
] = {
751 [IORING_OP_READ_FIXED
] = {
753 .unbound_nonreg_file
= 1,
756 [IORING_OP_WRITE_FIXED
] = {
759 .unbound_nonreg_file
= 1,
763 [IORING_OP_POLL_ADD
] = {
765 .unbound_nonreg_file
= 1,
767 [IORING_OP_POLL_REMOVE
] = {},
768 [IORING_OP_SYNC_FILE_RANGE
] = {
771 [IORING_OP_SENDMSG
] = {
775 .unbound_nonreg_file
= 1,
779 [IORING_OP_RECVMSG
] = {
783 .unbound_nonreg_file
= 1,
788 [IORING_OP_TIMEOUT
] = {
792 [IORING_OP_TIMEOUT_REMOVE
] = {},
793 [IORING_OP_ACCEPT
] = {
796 .unbound_nonreg_file
= 1,
800 [IORING_OP_ASYNC_CANCEL
] = {},
801 [IORING_OP_LINK_TIMEOUT
] = {
805 [IORING_OP_CONNECT
] = {
809 .unbound_nonreg_file
= 1,
812 [IORING_OP_FALLOCATE
] = {
816 [IORING_OP_OPENAT
] = {
820 [IORING_OP_CLOSE
] = {
822 .needs_file_no_error
= 1,
825 [IORING_OP_FILES_UPDATE
] = {
829 [IORING_OP_STATX
] = {
837 .unbound_nonreg_file
= 1,
841 [IORING_OP_WRITE
] = {
844 .unbound_nonreg_file
= 1,
848 [IORING_OP_FADVISE
] = {
851 [IORING_OP_MADVISE
] = {
857 .unbound_nonreg_file
= 1,
863 .unbound_nonreg_file
= 1,
867 [IORING_OP_OPENAT2
] = {
871 [IORING_OP_EPOLL_CTL
] = {
872 .unbound_nonreg_file
= 1,
875 [IORING_OP_SPLICE
] = {
878 .unbound_nonreg_file
= 1,
880 [IORING_OP_PROVIDE_BUFFERS
] = {},
881 [IORING_OP_REMOVE_BUFFERS
] = {},
885 .unbound_nonreg_file
= 1,
889 enum io_mem_account
{
894 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
895 struct io_comp_state
*cs
);
896 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
897 static void io_put_req(struct io_kiocb
*req
);
898 static void io_double_put_req(struct io_kiocb
*req
);
899 static void __io_double_put_req(struct io_kiocb
*req
);
900 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
901 static void io_queue_linked_timeout(struct io_kiocb
*req
);
902 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
903 struct io_uring_files_update
*ip
,
905 static int io_prep_work_files(struct io_kiocb
*req
);
906 static void __io_clean_op(struct io_kiocb
*req
);
907 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
908 int fd
, struct file
**out_file
, bool fixed
);
909 static void __io_queue_sqe(struct io_kiocb
*req
,
910 const struct io_uring_sqe
*sqe
,
911 struct io_comp_state
*cs
);
912 static void io_file_put_work(struct work_struct
*work
);
914 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
915 struct iovec
**iovec
, struct iov_iter
*iter
,
917 static int io_setup_async_rw(struct io_kiocb
*req
, ssize_t io_size
,
918 struct iovec
*iovec
, struct iovec
*fast_iov
,
919 struct iov_iter
*iter
);
921 static struct kmem_cache
*req_cachep
;
923 static const struct file_operations io_uring_fops
;
925 struct sock
*io_uring_get_socket(struct file
*file
)
927 #if defined(CONFIG_UNIX)
928 if (file
->f_op
== &io_uring_fops
) {
929 struct io_ring_ctx
*ctx
= file
->private_data
;
931 return ctx
->ring_sock
->sk
;
936 EXPORT_SYMBOL(io_uring_get_socket
);
938 static void io_get_req_task(struct io_kiocb
*req
)
940 if (req
->flags
& REQ_F_TASK_PINNED
)
942 get_task_struct(req
->task
);
943 req
->flags
|= REQ_F_TASK_PINNED
;
946 static inline void io_clean_op(struct io_kiocb
*req
)
948 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
))
952 /* not idempotent -- it doesn't clear REQ_F_TASK_PINNED */
953 static void __io_put_req_task(struct io_kiocb
*req
)
955 if (req
->flags
& REQ_F_TASK_PINNED
)
956 put_task_struct(req
->task
);
959 static void io_sq_thread_drop_mm(void)
961 struct mm_struct
*mm
= current
->mm
;
964 kthread_unuse_mm(mm
);
969 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
972 if (unlikely(!(ctx
->flags
& IORING_SETUP_SQPOLL
) ||
973 !mmget_not_zero(ctx
->sqo_mm
)))
975 kthread_use_mm(ctx
->sqo_mm
);
981 static int io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
,
982 struct io_kiocb
*req
)
984 if (!io_op_defs
[req
->opcode
].needs_mm
)
986 return __io_sq_thread_acquire_mm(ctx
);
989 static inline void req_set_fail_links(struct io_kiocb
*req
)
991 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
992 req
->flags
|= REQ_F_FAIL_LINK
;
996 * Note: must call io_req_init_async() for the first time you
997 * touch any members of io_wq_work.
999 static inline void io_req_init_async(struct io_kiocb
*req
)
1001 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1004 memset(&req
->work
, 0, sizeof(req
->work
));
1005 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1008 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
1010 return ctx
->flags
& IORING_SETUP_SQPOLL
;
1013 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1015 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1017 complete(&ctx
->ref_comp
);
1020 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1022 return !req
->timeout
.off
;
1025 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1027 struct io_ring_ctx
*ctx
;
1030 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1034 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
1035 if (!ctx
->fallback_req
)
1039 * Use 5 bits less than the max cq entries, that should give us around
1040 * 32 entries per hash list if totally full and uniformly spread.
1042 hash_bits
= ilog2(p
->cq_entries
);
1046 ctx
->cancel_hash_bits
= hash_bits
;
1047 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1049 if (!ctx
->cancel_hash
)
1051 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1053 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1054 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1057 ctx
->flags
= p
->flags
;
1058 init_waitqueue_head(&ctx
->sqo_wait
);
1059 init_waitqueue_head(&ctx
->cq_wait
);
1060 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1061 init_completion(&ctx
->ref_comp
);
1062 init_completion(&ctx
->sq_thread_comp
);
1063 idr_init(&ctx
->io_buffer_idr
);
1064 idr_init(&ctx
->personality_idr
);
1065 mutex_init(&ctx
->uring_lock
);
1066 init_waitqueue_head(&ctx
->wait
);
1067 spin_lock_init(&ctx
->completion_lock
);
1068 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1069 INIT_LIST_HEAD(&ctx
->defer_list
);
1070 INIT_LIST_HEAD(&ctx
->timeout_list
);
1071 init_waitqueue_head(&ctx
->inflight_wait
);
1072 spin_lock_init(&ctx
->inflight_lock
);
1073 INIT_LIST_HEAD(&ctx
->inflight_list
);
1074 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
1075 init_llist_head(&ctx
->file_put_llist
);
1078 if (ctx
->fallback_req
)
1079 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
1080 kfree(ctx
->cancel_hash
);
1085 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1087 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1088 struct io_ring_ctx
*ctx
= req
->ctx
;
1090 return seq
!= ctx
->cached_cq_tail
1091 + atomic_read(&ctx
->cached_cq_overflow
);
1097 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1099 struct io_rings
*rings
= ctx
->rings
;
1101 /* order cqe stores with ring update */
1102 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1104 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1105 wake_up_interruptible(&ctx
->cq_wait
);
1106 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1110 static void io_req_clean_work(struct io_kiocb
*req
)
1112 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1116 mmdrop(req
->work
.mm
);
1117 req
->work
.mm
= NULL
;
1119 if (req
->work
.creds
) {
1120 put_cred(req
->work
.creds
);
1121 req
->work
.creds
= NULL
;
1124 struct fs_struct
*fs
= req
->work
.fs
;
1126 spin_lock(&req
->work
.fs
->lock
);
1129 spin_unlock(&req
->work
.fs
->lock
);
1132 req
->work
.fs
= NULL
;
1134 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1137 static void io_prep_async_work(struct io_kiocb
*req
)
1139 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1141 io_req_init_async(req
);
1143 if (req
->flags
& REQ_F_ISREG
) {
1144 if (def
->hash_reg_file
)
1145 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1147 if (def
->unbound_nonreg_file
)
1148 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1150 if (!req
->work
.mm
&& def
->needs_mm
) {
1151 mmgrab(current
->mm
);
1152 req
->work
.mm
= current
->mm
;
1154 if (!req
->work
.creds
)
1155 req
->work
.creds
= get_current_cred();
1156 if (!req
->work
.fs
&& def
->needs_fs
) {
1157 spin_lock(¤t
->fs
->lock
);
1158 if (!current
->fs
->in_exec
) {
1159 req
->work
.fs
= current
->fs
;
1160 req
->work
.fs
->users
++;
1162 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1164 spin_unlock(¤t
->fs
->lock
);
1166 if (def
->needs_fsize
)
1167 req
->work
.fsize
= rlimit(RLIMIT_FSIZE
);
1169 req
->work
.fsize
= RLIM_INFINITY
;
1172 static void io_prep_async_link(struct io_kiocb
*req
)
1174 struct io_kiocb
*cur
;
1176 io_prep_async_work(req
);
1177 if (req
->flags
& REQ_F_LINK_HEAD
)
1178 list_for_each_entry(cur
, &req
->link_list
, link_list
)
1179 io_prep_async_work(cur
);
1182 static void __io_queue_async_work(struct io_kiocb
*req
)
1184 struct io_ring_ctx
*ctx
= req
->ctx
;
1185 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1187 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1188 &req
->work
, req
->flags
);
1189 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1192 io_queue_linked_timeout(link
);
1195 static void io_queue_async_work(struct io_kiocb
*req
)
1197 /* init ->work of the whole link before punting */
1198 io_prep_async_link(req
);
1199 __io_queue_async_work(req
);
1202 static void io_kill_timeout(struct io_kiocb
*req
)
1206 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1208 atomic_set(&req
->ctx
->cq_timeouts
,
1209 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1210 list_del_init(&req
->timeout
.list
);
1211 req
->flags
|= REQ_F_COMP_LOCKED
;
1212 io_cqring_fill_event(req
, 0);
1217 static void io_kill_timeouts(struct io_ring_ctx
*ctx
)
1219 struct io_kiocb
*req
, *tmp
;
1221 spin_lock_irq(&ctx
->completion_lock
);
1222 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
)
1223 io_kill_timeout(req
);
1224 spin_unlock_irq(&ctx
->completion_lock
);
1227 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1230 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1231 struct io_defer_entry
, list
);
1233 if (req_need_defer(de
->req
, de
->seq
))
1235 list_del_init(&de
->list
);
1236 /* punt-init is done before queueing for defer */
1237 __io_queue_async_work(de
->req
);
1239 } while (!list_empty(&ctx
->defer_list
));
1242 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1244 while (!list_empty(&ctx
->timeout_list
)) {
1245 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1246 struct io_kiocb
, timeout
.list
);
1248 if (io_is_timeout_noseq(req
))
1250 if (req
->timeout
.target_seq
!= ctx
->cached_cq_tail
1251 - atomic_read(&ctx
->cq_timeouts
))
1254 list_del_init(&req
->timeout
.list
);
1255 io_kill_timeout(req
);
1259 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1261 io_flush_timeouts(ctx
);
1262 __io_commit_cqring(ctx
);
1264 if (unlikely(!list_empty(&ctx
->defer_list
)))
1265 __io_queue_deferred(ctx
);
1268 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1270 struct io_rings
*rings
= ctx
->rings
;
1273 tail
= ctx
->cached_cq_tail
;
1275 * writes to the cq entry need to come after reading head; the
1276 * control dependency is enough as we're using WRITE_ONCE to
1279 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1282 ctx
->cached_cq_tail
++;
1283 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1286 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1290 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1292 if (!ctx
->eventfd_async
)
1294 return io_wq_current_is_worker();
1297 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1299 if (waitqueue_active(&ctx
->wait
))
1300 wake_up(&ctx
->wait
);
1301 if (waitqueue_active(&ctx
->sqo_wait
))
1302 wake_up(&ctx
->sqo_wait
);
1303 if (io_should_trigger_evfd(ctx
))
1304 eventfd_signal(ctx
->cq_ev_fd
, 1);
1307 static void io_cqring_mark_overflow(struct io_ring_ctx
*ctx
)
1309 if (list_empty(&ctx
->cq_overflow_list
)) {
1310 clear_bit(0, &ctx
->sq_check_overflow
);
1311 clear_bit(0, &ctx
->cq_check_overflow
);
1312 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1316 /* Returns true if there are no backlogged entries after the flush */
1317 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1319 struct io_rings
*rings
= ctx
->rings
;
1320 struct io_uring_cqe
*cqe
;
1321 struct io_kiocb
*req
;
1322 unsigned long flags
;
1326 if (list_empty_careful(&ctx
->cq_overflow_list
))
1328 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1329 rings
->cq_ring_entries
))
1333 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1335 /* if force is set, the ring is going away. always drop after that */
1337 ctx
->cq_overflow_flushed
= 1;
1340 while (!list_empty(&ctx
->cq_overflow_list
)) {
1341 cqe
= io_get_cqring(ctx
);
1345 req
= list_first_entry(&ctx
->cq_overflow_list
, struct io_kiocb
,
1347 list_move(&req
->compl.list
, &list
);
1348 req
->flags
&= ~REQ_F_OVERFLOW
;
1350 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1351 WRITE_ONCE(cqe
->res
, req
->result
);
1352 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1354 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1355 atomic_inc_return(&ctx
->cached_cq_overflow
));
1359 io_commit_cqring(ctx
);
1360 io_cqring_mark_overflow(ctx
);
1362 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1363 io_cqring_ev_posted(ctx
);
1365 while (!list_empty(&list
)) {
1366 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1367 list_del(&req
->compl.list
);
1374 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1376 struct io_ring_ctx
*ctx
= req
->ctx
;
1377 struct io_uring_cqe
*cqe
;
1379 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1382 * If we can't get a cq entry, userspace overflowed the
1383 * submission (by quite a lot). Increment the overflow count in
1386 cqe
= io_get_cqring(ctx
);
1388 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1389 WRITE_ONCE(cqe
->res
, res
);
1390 WRITE_ONCE(cqe
->flags
, cflags
);
1391 } else if (ctx
->cq_overflow_flushed
) {
1392 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1393 atomic_inc_return(&ctx
->cached_cq_overflow
));
1395 if (list_empty(&ctx
->cq_overflow_list
)) {
1396 set_bit(0, &ctx
->sq_check_overflow
);
1397 set_bit(0, &ctx
->cq_check_overflow
);
1398 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1401 req
->flags
|= REQ_F_OVERFLOW
;
1403 req
->compl.cflags
= cflags
;
1404 refcount_inc(&req
->refs
);
1405 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1409 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1411 __io_cqring_fill_event(req
, res
, 0);
1414 static void io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1416 struct io_ring_ctx
*ctx
= req
->ctx
;
1417 unsigned long flags
;
1419 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1420 __io_cqring_fill_event(req
, res
, cflags
);
1421 io_commit_cqring(ctx
);
1422 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1424 io_cqring_ev_posted(ctx
);
1427 static void io_submit_flush_completions(struct io_comp_state
*cs
)
1429 struct io_ring_ctx
*ctx
= cs
->ctx
;
1431 spin_lock_irq(&ctx
->completion_lock
);
1432 while (!list_empty(&cs
->list
)) {
1433 struct io_kiocb
*req
;
1435 req
= list_first_entry(&cs
->list
, struct io_kiocb
, compl.list
);
1436 list_del(&req
->compl.list
);
1437 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
1438 if (!(req
->flags
& REQ_F_LINK_HEAD
)) {
1439 req
->flags
|= REQ_F_COMP_LOCKED
;
1442 spin_unlock_irq(&ctx
->completion_lock
);
1444 spin_lock_irq(&ctx
->completion_lock
);
1447 io_commit_cqring(ctx
);
1448 spin_unlock_irq(&ctx
->completion_lock
);
1450 io_cqring_ev_posted(ctx
);
1454 static void __io_req_complete(struct io_kiocb
*req
, long res
, unsigned cflags
,
1455 struct io_comp_state
*cs
)
1458 io_cqring_add_event(req
, res
, cflags
);
1463 req
->compl.cflags
= cflags
;
1464 list_add_tail(&req
->compl.list
, &cs
->list
);
1466 io_submit_flush_completions(cs
);
1470 static void io_req_complete(struct io_kiocb
*req
, long res
)
1472 __io_req_complete(req
, res
, 0, NULL
);
1475 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1477 return req
== (struct io_kiocb
*)
1478 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1481 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1483 struct io_kiocb
*req
;
1485 req
= ctx
->fallback_req
;
1486 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1492 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1493 struct io_submit_state
*state
)
1495 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1496 struct io_kiocb
*req
;
1498 if (!state
->free_reqs
) {
1502 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1503 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1506 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1507 * retry single alloc to be on the safe side.
1509 if (unlikely(ret
<= 0)) {
1510 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1511 if (!state
->reqs
[0])
1515 state
->free_reqs
= ret
- 1;
1516 req
= state
->reqs
[ret
- 1];
1519 req
= state
->reqs
[state
->free_reqs
];
1524 return io_get_fallback_req(ctx
);
1527 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1531 percpu_ref_put(req
->fixed_file_refs
);
1536 static void io_dismantle_req(struct io_kiocb
*req
)
1543 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1544 io_req_clean_work(req
);
1546 if (req
->flags
& REQ_F_INFLIGHT
) {
1547 struct io_ring_ctx
*ctx
= req
->ctx
;
1548 unsigned long flags
;
1550 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
1551 list_del(&req
->inflight_entry
);
1552 if (waitqueue_active(&ctx
->inflight_wait
))
1553 wake_up(&ctx
->inflight_wait
);
1554 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
1558 static void __io_free_req(struct io_kiocb
*req
)
1560 struct io_ring_ctx
*ctx
;
1562 io_dismantle_req(req
);
1563 __io_put_req_task(req
);
1565 if (likely(!io_is_fallback_req(req
)))
1566 kmem_cache_free(req_cachep
, req
);
1568 clear_bit_unlock(0, (unsigned long *) &ctx
->fallback_req
);
1569 percpu_ref_put(&ctx
->refs
);
1572 static bool io_link_cancel_timeout(struct io_kiocb
*req
)
1574 struct io_ring_ctx
*ctx
= req
->ctx
;
1577 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1579 io_cqring_fill_event(req
, -ECANCELED
);
1580 io_commit_cqring(ctx
);
1581 req
->flags
&= ~REQ_F_LINK_HEAD
;
1589 static bool __io_kill_linked_timeout(struct io_kiocb
*req
)
1591 struct io_kiocb
*link
;
1594 if (list_empty(&req
->link_list
))
1596 link
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1597 if (link
->opcode
!= IORING_OP_LINK_TIMEOUT
)
1600 list_del_init(&link
->link_list
);
1601 wake_ev
= io_link_cancel_timeout(link
);
1602 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1606 static void io_kill_linked_timeout(struct io_kiocb
*req
)
1608 struct io_ring_ctx
*ctx
= req
->ctx
;
1611 if (!(req
->flags
& REQ_F_COMP_LOCKED
)) {
1612 unsigned long flags
;
1614 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1615 wake_ev
= __io_kill_linked_timeout(req
);
1616 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1618 wake_ev
= __io_kill_linked_timeout(req
);
1622 io_cqring_ev_posted(ctx
);
1625 static struct io_kiocb
*io_req_link_next(struct io_kiocb
*req
)
1627 struct io_kiocb
*nxt
;
1630 * The list should never be empty when we are called here. But could
1631 * potentially happen if the chain is messed up, check to be on the
1634 if (unlikely(list_empty(&req
->link_list
)))
1637 nxt
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1638 list_del_init(&req
->link_list
);
1639 if (!list_empty(&nxt
->link_list
))
1640 nxt
->flags
|= REQ_F_LINK_HEAD
;
1645 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
1647 static void __io_fail_links(struct io_kiocb
*req
)
1649 struct io_ring_ctx
*ctx
= req
->ctx
;
1651 while (!list_empty(&req
->link_list
)) {
1652 struct io_kiocb
*link
= list_first_entry(&req
->link_list
,
1653 struct io_kiocb
, link_list
);
1655 list_del_init(&link
->link_list
);
1656 trace_io_uring_fail_link(req
, link
);
1658 io_cqring_fill_event(link
, -ECANCELED
);
1659 __io_double_put_req(link
);
1660 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1663 io_commit_cqring(ctx
);
1664 io_cqring_ev_posted(ctx
);
1667 static void io_fail_links(struct io_kiocb
*req
)
1669 struct io_ring_ctx
*ctx
= req
->ctx
;
1671 if (!(req
->flags
& REQ_F_COMP_LOCKED
)) {
1672 unsigned long flags
;
1674 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1675 __io_fail_links(req
);
1676 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1678 __io_fail_links(req
);
1681 io_cqring_ev_posted(ctx
);
1684 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
1686 req
->flags
&= ~REQ_F_LINK_HEAD
;
1687 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
1688 io_kill_linked_timeout(req
);
1691 * If LINK is set, we have dependent requests in this chain. If we
1692 * didn't fail this request, queue the first one up, moving any other
1693 * dependencies to the next request. In case of failure, fail the rest
1696 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
)))
1697 return io_req_link_next(req
);
1702 static struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
1704 if (likely(!(req
->flags
& REQ_F_LINK_HEAD
)))
1706 return __io_req_find_next(req
);
1709 static int io_req_task_work_add(struct io_kiocb
*req
, struct callback_head
*cb
)
1711 struct task_struct
*tsk
= req
->task
;
1712 struct io_ring_ctx
*ctx
= req
->ctx
;
1713 int ret
, notify
= TWA_RESUME
;
1716 * SQPOLL kernel thread doesn't need notification, just a wakeup.
1717 * If we're not using an eventfd, then TWA_RESUME is always fine,
1718 * as we won't have dependencies between request completions for
1719 * other kernel wait conditions.
1721 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
1723 else if (ctx
->cq_ev_fd
)
1724 notify
= TWA_SIGNAL
;
1726 ret
= task_work_add(tsk
, cb
, notify
);
1728 wake_up_process(tsk
);
1732 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
1734 struct io_ring_ctx
*ctx
= req
->ctx
;
1736 spin_lock_irq(&ctx
->completion_lock
);
1737 io_cqring_fill_event(req
, error
);
1738 io_commit_cqring(ctx
);
1739 spin_unlock_irq(&ctx
->completion_lock
);
1741 io_cqring_ev_posted(ctx
);
1742 req_set_fail_links(req
);
1743 io_double_put_req(req
);
1746 static void io_req_task_cancel(struct callback_head
*cb
)
1748 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
1750 __io_req_task_cancel(req
, -ECANCELED
);
1753 static void __io_req_task_submit(struct io_kiocb
*req
)
1755 struct io_ring_ctx
*ctx
= req
->ctx
;
1757 if (!__io_sq_thread_acquire_mm(ctx
)) {
1758 mutex_lock(&ctx
->uring_lock
);
1759 __io_queue_sqe(req
, NULL
, NULL
);
1760 mutex_unlock(&ctx
->uring_lock
);
1762 __io_req_task_cancel(req
, -EFAULT
);
1766 static void io_req_task_submit(struct callback_head
*cb
)
1768 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
1770 __io_req_task_submit(req
);
1773 static void io_req_task_queue(struct io_kiocb
*req
)
1777 init_task_work(&req
->task_work
, io_req_task_submit
);
1779 ret
= io_req_task_work_add(req
, &req
->task_work
);
1780 if (unlikely(ret
)) {
1781 struct task_struct
*tsk
;
1783 init_task_work(&req
->task_work
, io_req_task_cancel
);
1784 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
1785 task_work_add(tsk
, &req
->task_work
, 0);
1786 wake_up_process(tsk
);
1790 static void io_queue_next(struct io_kiocb
*req
)
1792 struct io_kiocb
*nxt
= io_req_find_next(req
);
1795 io_req_task_queue(nxt
);
1798 static void io_free_req(struct io_kiocb
*req
)
1805 void *reqs
[IO_IOPOLL_BATCH
];
1808 struct task_struct
*task
;
1812 static inline void io_init_req_batch(struct req_batch
*rb
)
1819 static void __io_req_free_batch_flush(struct io_ring_ctx
*ctx
,
1820 struct req_batch
*rb
)
1822 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
1823 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
1827 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
1828 struct req_batch
*rb
)
1831 __io_req_free_batch_flush(ctx
, rb
);
1833 put_task_struct_many(rb
->task
, rb
->task_refs
);
1838 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
)
1840 if (unlikely(io_is_fallback_req(req
))) {
1844 if (req
->flags
& REQ_F_LINK_HEAD
)
1847 if (req
->flags
& REQ_F_TASK_PINNED
) {
1848 if (req
->task
!= rb
->task
) {
1850 put_task_struct_many(rb
->task
, rb
->task_refs
);
1851 rb
->task
= req
->task
;
1855 req
->flags
&= ~REQ_F_TASK_PINNED
;
1858 io_dismantle_req(req
);
1859 rb
->reqs
[rb
->to_free
++] = req
;
1860 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
1861 __io_req_free_batch_flush(req
->ctx
, rb
);
1865 * Drop reference to request, return next in chain (if there is one) if this
1866 * was the last reference to this request.
1868 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
1870 struct io_kiocb
*nxt
= NULL
;
1872 if (refcount_dec_and_test(&req
->refs
)) {
1873 nxt
= io_req_find_next(req
);
1879 static void io_put_req(struct io_kiocb
*req
)
1881 if (refcount_dec_and_test(&req
->refs
))
1885 static struct io_wq_work
*io_steal_work(struct io_kiocb
*req
)
1887 struct io_kiocb
*nxt
;
1890 * A ref is owned by io-wq in which context we're. So, if that's the
1891 * last one, it's safe to steal next work. False negatives are Ok,
1892 * it just will be re-punted async in io_put_work()
1894 if (refcount_read(&req
->refs
) != 1)
1897 nxt
= io_req_find_next(req
);
1898 return nxt
? &nxt
->work
: NULL
;
1902 * Must only be used if we don't need to care about links, usually from
1903 * within the completion handling itself.
1905 static void __io_double_put_req(struct io_kiocb
*req
)
1907 /* drop both submit and complete references */
1908 if (refcount_sub_and_test(2, &req
->refs
))
1912 static void io_double_put_req(struct io_kiocb
*req
)
1914 /* drop both submit and complete references */
1915 if (refcount_sub_and_test(2, &req
->refs
))
1919 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
1921 struct io_rings
*rings
= ctx
->rings
;
1923 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1925 * noflush == true is from the waitqueue handler, just ensure
1926 * we wake up the task, and the next invocation will flush the
1927 * entries. We cannot safely to it from here.
1929 if (noflush
&& !list_empty(&ctx
->cq_overflow_list
))
1932 io_cqring_overflow_flush(ctx
, false);
1935 /* See comment at the top of this file */
1937 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
1940 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
1942 struct io_rings
*rings
= ctx
->rings
;
1944 /* make sure SQ entry isn't read before tail */
1945 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
1948 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
1950 unsigned int cflags
;
1952 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
1953 cflags
|= IORING_CQE_F_BUFFER
;
1954 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
1959 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
1961 struct io_buffer
*kbuf
;
1963 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
1964 return io_put_kbuf(req
, kbuf
);
1967 static inline bool io_run_task_work(void)
1969 if (current
->task_works
) {
1970 __set_current_state(TASK_RUNNING
);
1978 static void io_iopoll_queue(struct list_head
*again
)
1980 struct io_kiocb
*req
;
1983 req
= list_first_entry(again
, struct io_kiocb
, inflight_entry
);
1984 list_del(&req
->inflight_entry
);
1985 __io_complete_rw(req
, -EAGAIN
, 0, NULL
);
1986 } while (!list_empty(again
));
1990 * Find and free completed poll iocbs
1992 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
1993 struct list_head
*done
)
1995 struct req_batch rb
;
1996 struct io_kiocb
*req
;
1999 /* order with ->result store in io_complete_rw_iopoll() */
2002 io_init_req_batch(&rb
);
2003 while (!list_empty(done
)) {
2006 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2007 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2008 req
->iopoll_completed
= 0;
2009 list_move_tail(&req
->inflight_entry
, &again
);
2012 list_del(&req
->inflight_entry
);
2014 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2015 cflags
= io_put_rw_kbuf(req
);
2017 __io_cqring_fill_event(req
, req
->result
, cflags
);
2020 if (refcount_dec_and_test(&req
->refs
))
2021 io_req_free_batch(&rb
, req
);
2024 io_commit_cqring(ctx
);
2025 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
2026 io_cqring_ev_posted(ctx
);
2027 io_req_free_batch_finish(ctx
, &rb
);
2029 if (!list_empty(&again
))
2030 io_iopoll_queue(&again
);
2033 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2036 struct io_kiocb
*req
, *tmp
;
2042 * Only spin for completions if we don't have multiple devices hanging
2043 * off our complete list, and we're under the requested amount.
2045 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2048 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2049 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2052 * Move completed and retryable entries to our local lists.
2053 * If we find a request that requires polling, break out
2054 * and complete those lists first, if we have entries there.
2056 if (READ_ONCE(req
->iopoll_completed
)) {
2057 list_move_tail(&req
->inflight_entry
, &done
);
2060 if (!list_empty(&done
))
2063 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2067 /* iopoll may have completed current req */
2068 if (READ_ONCE(req
->iopoll_completed
))
2069 list_move_tail(&req
->inflight_entry
, &done
);
2076 if (!list_empty(&done
))
2077 io_iopoll_complete(ctx
, nr_events
, &done
);
2083 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2084 * non-spinning poll check - we'll still enter the driver poll loop, but only
2085 * as a non-spinning completion check.
2087 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2090 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2093 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2096 if (*nr_events
>= min
)
2104 * We can't just wait for polled events to come to us, we have to actively
2105 * find and complete them.
2107 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2109 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2112 mutex_lock(&ctx
->uring_lock
);
2113 while (!list_empty(&ctx
->iopoll_list
)) {
2114 unsigned int nr_events
= 0;
2116 io_do_iopoll(ctx
, &nr_events
, 0);
2118 /* let it sleep and repeat later if can't complete a request */
2122 * Ensure we allow local-to-the-cpu processing to take place,
2123 * in this case we need to ensure that we reap all events.
2124 * Also let task_work, etc. to progress by releasing the mutex
2126 if (need_resched()) {
2127 mutex_unlock(&ctx
->uring_lock
);
2129 mutex_lock(&ctx
->uring_lock
);
2132 mutex_unlock(&ctx
->uring_lock
);
2135 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2137 unsigned int nr_events
= 0;
2138 int iters
= 0, ret
= 0;
2141 * We disallow the app entering submit/complete with polling, but we
2142 * still need to lock the ring to prevent racing with polled issue
2143 * that got punted to a workqueue.
2145 mutex_lock(&ctx
->uring_lock
);
2148 * Don't enter poll loop if we already have events pending.
2149 * If we do, we can potentially be spinning for commands that
2150 * already triggered a CQE (eg in error).
2152 if (io_cqring_events(ctx
, false))
2156 * If a submit got punted to a workqueue, we can have the
2157 * application entering polling for a command before it gets
2158 * issued. That app will hold the uring_lock for the duration
2159 * of the poll right here, so we need to take a breather every
2160 * now and then to ensure that the issue has a chance to add
2161 * the poll to the issued list. Otherwise we can spin here
2162 * forever, while the workqueue is stuck trying to acquire the
2165 if (!(++iters
& 7)) {
2166 mutex_unlock(&ctx
->uring_lock
);
2168 mutex_lock(&ctx
->uring_lock
);
2171 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2175 } while (min
&& !nr_events
&& !need_resched());
2177 mutex_unlock(&ctx
->uring_lock
);
2181 static void kiocb_end_write(struct io_kiocb
*req
)
2184 * Tell lockdep we inherited freeze protection from submission
2187 if (req
->flags
& REQ_F_ISREG
) {
2188 struct inode
*inode
= file_inode(req
->file
);
2190 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2192 file_end_write(req
->file
);
2195 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
,
2196 struct io_comp_state
*cs
)
2198 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2201 if (kiocb
->ki_flags
& IOCB_WRITE
)
2202 kiocb_end_write(req
);
2204 if (res
!= req
->result
)
2205 req_set_fail_links(req
);
2206 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2207 cflags
= io_put_rw_kbuf(req
);
2208 __io_req_complete(req
, res
, cflags
, cs
);
2212 static bool io_resubmit_prep(struct io_kiocb
*req
, int error
)
2214 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2215 ssize_t ret
= -ECANCELED
;
2216 struct iov_iter iter
;
2224 switch (req
->opcode
) {
2225 case IORING_OP_READV
:
2226 case IORING_OP_READ_FIXED
:
2227 case IORING_OP_READ
:
2230 case IORING_OP_WRITEV
:
2231 case IORING_OP_WRITE_FIXED
:
2232 case IORING_OP_WRITE
:
2236 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2241 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2244 ret
= io_setup_async_rw(req
, ret
, iovec
, inline_vecs
, &iter
);
2249 req_set_fail_links(req
);
2250 io_req_complete(req
, ret
);
2254 static void io_rw_resubmit(struct callback_head
*cb
)
2256 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2257 struct io_ring_ctx
*ctx
= req
->ctx
;
2260 err
= io_sq_thread_acquire_mm(ctx
, req
);
2262 if (io_resubmit_prep(req
, err
)) {
2263 refcount_inc(&req
->refs
);
2264 io_queue_async_work(req
);
2269 static bool io_rw_reissue(struct io_kiocb
*req
, long res
)
2274 if ((res
!= -EAGAIN
&& res
!= -EOPNOTSUPP
) || io_wq_current_is_worker())
2277 init_task_work(&req
->task_work
, io_rw_resubmit
);
2278 ret
= io_req_task_work_add(req
, &req
->task_work
);
2285 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2286 struct io_comp_state
*cs
)
2288 if (!io_rw_reissue(req
, res
))
2289 io_complete_rw_common(&req
->rw
.kiocb
, res
, cs
);
2292 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2294 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2296 __io_complete_rw(req
, res
, res2
, NULL
);
2299 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2301 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2303 if (kiocb
->ki_flags
& IOCB_WRITE
)
2304 kiocb_end_write(req
);
2306 if (res
!= -EAGAIN
&& res
!= req
->result
)
2307 req_set_fail_links(req
);
2309 WRITE_ONCE(req
->result
, res
);
2310 /* order with io_poll_complete() checking ->result */
2312 WRITE_ONCE(req
->iopoll_completed
, 1);
2316 * After the iocb has been issued, it's safe to be found on the poll list.
2317 * Adding the kiocb to the list AFTER submission ensures that we don't
2318 * find it from a io_iopoll_getevents() thread before the issuer is done
2319 * accessing the kiocb cookie.
2321 static void io_iopoll_req_issued(struct io_kiocb
*req
)
2323 struct io_ring_ctx
*ctx
= req
->ctx
;
2326 * Track whether we have multiple files in our lists. This will impact
2327 * how we do polling eventually, not spinning if we're on potentially
2328 * different devices.
2330 if (list_empty(&ctx
->iopoll_list
)) {
2331 ctx
->poll_multi_file
= false;
2332 } else if (!ctx
->poll_multi_file
) {
2333 struct io_kiocb
*list_req
;
2335 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2337 if (list_req
->file
!= req
->file
)
2338 ctx
->poll_multi_file
= true;
2342 * For fast devices, IO may have already completed. If it has, add
2343 * it to the front so we find it first.
2345 if (READ_ONCE(req
->iopoll_completed
))
2346 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2348 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2350 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2351 wq_has_sleeper(&ctx
->sqo_wait
))
2352 wake_up(&ctx
->sqo_wait
);
2355 static void __io_state_file_put(struct io_submit_state
*state
)
2357 if (state
->has_refs
)
2358 fput_many(state
->file
, state
->has_refs
);
2362 static inline void io_state_file_put(struct io_submit_state
*state
)
2365 __io_state_file_put(state
);
2369 * Get as many references to a file as we have IOs left in this submission,
2370 * assuming most submissions are for one file, or at least that each file
2371 * has more than one submission.
2373 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2379 if (state
->fd
== fd
) {
2384 __io_state_file_put(state
);
2386 state
->file
= fget_many(fd
, state
->ios_left
);
2392 state
->has_refs
= state
->ios_left
;
2396 static bool io_bdev_nowait(struct block_device
*bdev
)
2399 return !bdev
|| queue_is_mq(bdev_get_queue(bdev
));
2406 * If we tracked the file through the SCM inflight mechanism, we could support
2407 * any file. For now, just ensure that anything potentially problematic is done
2410 static bool io_file_supports_async(struct file
*file
, int rw
)
2412 umode_t mode
= file_inode(file
)->i_mode
;
2414 if (S_ISBLK(mode
)) {
2415 if (io_bdev_nowait(file
->f_inode
->i_bdev
))
2419 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2421 if (S_ISREG(mode
)) {
2422 if (io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2423 file
->f_op
!= &io_uring_fops
)
2428 /* any ->read/write should understand O_NONBLOCK */
2429 if (file
->f_flags
& O_NONBLOCK
)
2432 if (!(file
->f_mode
& FMODE_NOWAIT
))
2436 return file
->f_op
->read_iter
!= NULL
;
2438 return file
->f_op
->write_iter
!= NULL
;
2441 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2442 bool force_nonblock
)
2444 struct io_ring_ctx
*ctx
= req
->ctx
;
2445 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2449 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2450 req
->flags
|= REQ_F_ISREG
;
2452 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2453 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2454 req
->flags
|= REQ_F_CUR_POS
;
2455 kiocb
->ki_pos
= req
->file
->f_pos
;
2457 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2458 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2459 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2463 ioprio
= READ_ONCE(sqe
->ioprio
);
2465 ret
= ioprio_check_cap(ioprio
);
2469 kiocb
->ki_ioprio
= ioprio
;
2471 kiocb
->ki_ioprio
= get_current_ioprio();
2473 /* don't allow async punt if RWF_NOWAIT was requested */
2474 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2475 req
->flags
|= REQ_F_NOWAIT
;
2477 if (kiocb
->ki_flags
& IOCB_DIRECT
)
2478 io_get_req_task(req
);
2481 kiocb
->ki_flags
|= IOCB_NOWAIT
;
2483 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2484 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2485 !kiocb
->ki_filp
->f_op
->iopoll
)
2488 kiocb
->ki_flags
|= IOCB_HIPRI
;
2489 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2490 req
->iopoll_completed
= 0;
2491 io_get_req_task(req
);
2493 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2495 kiocb
->ki_complete
= io_complete_rw
;
2498 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2499 req
->rw
.len
= READ_ONCE(sqe
->len
);
2500 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2504 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2510 case -ERESTARTNOINTR
:
2511 case -ERESTARTNOHAND
:
2512 case -ERESTART_RESTARTBLOCK
:
2514 * We can't just restart the syscall, since previously
2515 * submitted sqes may already be in progress. Just fail this
2521 kiocb
->ki_complete(kiocb
, ret
, 0);
2525 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2526 struct io_comp_state
*cs
)
2528 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2530 if (req
->flags
& REQ_F_CUR_POS
)
2531 req
->file
->f_pos
= kiocb
->ki_pos
;
2532 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2533 __io_complete_rw(req
, ret
, 0, cs
);
2535 io_rw_done(kiocb
, ret
);
2538 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2539 struct iov_iter
*iter
)
2541 struct io_ring_ctx
*ctx
= req
->ctx
;
2542 size_t len
= req
->rw
.len
;
2543 struct io_mapped_ubuf
*imu
;
2544 u16 index
, buf_index
;
2548 /* attempt to use fixed buffers without having provided iovecs */
2549 if (unlikely(!ctx
->user_bufs
))
2552 buf_index
= req
->buf_index
;
2553 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2556 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2557 imu
= &ctx
->user_bufs
[index
];
2558 buf_addr
= req
->rw
.addr
;
2561 if (buf_addr
+ len
< buf_addr
)
2563 /* not inside the mapped region */
2564 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2568 * May not be a start of buffer, set size appropriately
2569 * and advance us to the beginning.
2571 offset
= buf_addr
- imu
->ubuf
;
2572 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2576 * Don't use iov_iter_advance() here, as it's really slow for
2577 * using the latter parts of a big fixed buffer - it iterates
2578 * over each segment manually. We can cheat a bit here, because
2581 * 1) it's a BVEC iter, we set it up
2582 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2583 * first and last bvec
2585 * So just find our index, and adjust the iterator afterwards.
2586 * If the offset is within the first bvec (or the whole first
2587 * bvec, just use iov_iter_advance(). This makes it easier
2588 * since we can just skip the first segment, which may not
2589 * be PAGE_SIZE aligned.
2591 const struct bio_vec
*bvec
= imu
->bvec
;
2593 if (offset
<= bvec
->bv_len
) {
2594 iov_iter_advance(iter
, offset
);
2596 unsigned long seg_skip
;
2598 /* skip first vec */
2599 offset
-= bvec
->bv_len
;
2600 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2602 iter
->bvec
= bvec
+ seg_skip
;
2603 iter
->nr_segs
-= seg_skip
;
2604 iter
->count
-= bvec
->bv_len
+ offset
;
2605 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2612 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2615 mutex_unlock(&ctx
->uring_lock
);
2618 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2621 * "Normal" inline submissions always hold the uring_lock, since we
2622 * grab it from the system call. Same is true for the SQPOLL offload.
2623 * The only exception is when we've detached the request and issue it
2624 * from an async worker thread, grab the lock for that case.
2627 mutex_lock(&ctx
->uring_lock
);
2630 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2631 int bgid
, struct io_buffer
*kbuf
,
2634 struct io_buffer
*head
;
2636 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2639 io_ring_submit_lock(req
->ctx
, needs_lock
);
2641 lockdep_assert_held(&req
->ctx
->uring_lock
);
2643 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
2645 if (!list_empty(&head
->list
)) {
2646 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2648 list_del(&kbuf
->list
);
2651 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
2653 if (*len
> kbuf
->len
)
2656 kbuf
= ERR_PTR(-ENOBUFS
);
2659 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2664 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2667 struct io_buffer
*kbuf
;
2670 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2671 bgid
= req
->buf_index
;
2672 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2675 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2676 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2677 return u64_to_user_ptr(kbuf
->addr
);
2680 #ifdef CONFIG_COMPAT
2681 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2684 struct compat_iovec __user
*uiov
;
2685 compat_ssize_t clen
;
2689 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2690 if (!access_ok(uiov
, sizeof(*uiov
)))
2692 if (__get_user(clen
, &uiov
->iov_len
))
2698 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2700 return PTR_ERR(buf
);
2701 iov
[0].iov_base
= buf
;
2702 iov
[0].iov_len
= (compat_size_t
) len
;
2707 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2710 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2714 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
2717 len
= iov
[0].iov_len
;
2720 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2722 return PTR_ERR(buf
);
2723 iov
[0].iov_base
= buf
;
2724 iov
[0].iov_len
= len
;
2728 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2731 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
2732 struct io_buffer
*kbuf
;
2734 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2735 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
2736 iov
[0].iov_len
= kbuf
->len
;
2741 else if (req
->rw
.len
> 1)
2744 #ifdef CONFIG_COMPAT
2745 if (req
->ctx
->compat
)
2746 return io_compat_import(req
, iov
, needs_lock
);
2749 return __io_iov_buffer_select(req
, iov
, needs_lock
);
2752 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
2753 struct iovec
**iovec
, struct iov_iter
*iter
,
2756 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
2757 size_t sqe_len
= req
->rw
.len
;
2761 opcode
= req
->opcode
;
2762 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
2764 return io_import_fixed(req
, rw
, iter
);
2767 /* buffer index only valid with fixed read/write, or buffer select */
2768 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
2771 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
2772 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2773 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
2776 return PTR_ERR(buf
);
2778 req
->rw
.len
= sqe_len
;
2781 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
2783 return ret
< 0 ? ret
: sqe_len
;
2787 struct io_async_rw
*iorw
= &req
->io
->rw
;
2789 iov_iter_init(iter
, rw
, iorw
->iov
, iorw
->nr_segs
, iorw
->size
);
2794 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2795 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
2797 ret
= (*iovec
)->iov_len
;
2798 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
2804 #ifdef CONFIG_COMPAT
2805 if (req
->ctx
->compat
)
2806 return compat_import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
,
2810 return import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
);
2814 * For files that don't have ->read_iter() and ->write_iter(), handle them
2815 * by looping over ->read() or ->write() manually.
2817 static ssize_t
loop_rw_iter(int rw
, struct file
*file
, struct kiocb
*kiocb
,
2818 struct iov_iter
*iter
)
2823 * Don't support polled IO through this interface, and we can't
2824 * support non-blocking either. For the latter, this just causes
2825 * the kiocb to be handled from an async context.
2827 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2829 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2832 while (iov_iter_count(iter
)) {
2836 if (!iov_iter_is_bvec(iter
)) {
2837 iovec
= iov_iter_iovec(iter
);
2839 /* fixed buffers import bvec */
2840 iovec
.iov_base
= kmap(iter
->bvec
->bv_page
)
2842 iovec
.iov_len
= min(iter
->count
,
2843 iter
->bvec
->bv_len
- iter
->iov_offset
);
2847 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
2848 iovec
.iov_len
, &kiocb
->ki_pos
);
2850 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
2851 iovec
.iov_len
, &kiocb
->ki_pos
);
2854 if (iov_iter_is_bvec(iter
))
2855 kunmap(iter
->bvec
->bv_page
);
2863 if (nr
!= iovec
.iov_len
)
2865 iov_iter_advance(iter
, nr
);
2871 static void io_req_map_rw(struct io_kiocb
*req
, ssize_t io_size
,
2872 struct iovec
*iovec
, struct iovec
*fast_iov
,
2873 struct iov_iter
*iter
)
2875 struct io_async_rw
*rw
= &req
->io
->rw
;
2877 rw
->nr_segs
= iter
->nr_segs
;
2880 rw
->iov
= rw
->fast_iov
;
2881 if (rw
->iov
!= fast_iov
)
2882 memcpy(rw
->iov
, fast_iov
,
2883 sizeof(struct iovec
) * iter
->nr_segs
);
2886 req
->flags
|= REQ_F_NEED_CLEANUP
;
2890 static inline int __io_alloc_async_ctx(struct io_kiocb
*req
)
2892 req
->io
= kmalloc(sizeof(*req
->io
), GFP_KERNEL
);
2893 return req
->io
== NULL
;
2896 static int io_alloc_async_ctx(struct io_kiocb
*req
)
2898 if (!io_op_defs
[req
->opcode
].async_ctx
)
2901 return __io_alloc_async_ctx(req
);
2904 static int io_setup_async_rw(struct io_kiocb
*req
, ssize_t io_size
,
2905 struct iovec
*iovec
, struct iovec
*fast_iov
,
2906 struct iov_iter
*iter
)
2908 if (!io_op_defs
[req
->opcode
].async_ctx
)
2911 if (__io_alloc_async_ctx(req
))
2914 io_req_map_rw(req
, io_size
, iovec
, fast_iov
, iter
);
2919 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
,
2920 bool force_nonblock
)
2922 struct io_async_ctx
*io
= req
->io
;
2923 struct iov_iter iter
;
2926 io
->rw
.iov
= io
->rw
.fast_iov
;
2928 ret
= io_import_iovec(rw
, req
, &io
->rw
.iov
, &iter
, !force_nonblock
);
2930 if (unlikely(ret
< 0))
2933 io_req_map_rw(req
, ret
, io
->rw
.iov
, io
->rw
.fast_iov
, &iter
);
2937 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2938 bool force_nonblock
)
2942 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
2946 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
2949 /* either don't need iovec imported or already have it */
2950 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
2952 return io_rw_prep_async(req
, READ
, force_nonblock
);
2955 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
2956 int sync
, void *arg
)
2958 struct wait_page_queue
*wpq
;
2959 struct io_kiocb
*req
= wait
->private;
2960 struct wait_page_key
*key
= arg
;
2963 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
2965 if (!wake_page_match(wpq
, key
))
2968 /* Stop waking things up if the page is locked again */
2969 if (test_bit(key
->bit_nr
, &key
->page
->flags
))
2972 list_del_init(&wait
->entry
);
2974 init_task_work(&req
->task_work
, io_req_task_submit
);
2975 /* submit ref gets dropped, acquire a new one */
2976 refcount_inc(&req
->refs
);
2977 ret
= io_req_task_work_add(req
, &req
->task_work
);
2978 if (unlikely(ret
)) {
2979 struct task_struct
*tsk
;
2981 /* queue just for cancelation */
2982 init_task_work(&req
->task_work
, io_req_task_cancel
);
2983 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
2984 task_work_add(tsk
, &req
->task_work
, 0);
2985 wake_up_process(tsk
);
2990 static inline int kiocb_wait_page_queue_init(struct kiocb
*kiocb
,
2991 struct wait_page_queue
*wait
,
2992 wait_queue_func_t func
,
2995 /* Can't support async wakeup with polled IO */
2996 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2998 if (kiocb
->ki_filp
->f_mode
& FMODE_BUF_RASYNC
) {
2999 wait
->wait
.func
= func
;
3000 wait
->wait
.private = data
;
3001 wait
->wait
.flags
= 0;
3002 INIT_LIST_HEAD(&wait
->wait
.entry
);
3003 kiocb
->ki_flags
|= IOCB_WAITQ
;
3004 kiocb
->ki_waitq
= wait
;
3012 static bool io_rw_should_retry(struct io_kiocb
*req
)
3014 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3017 /* never retry for NOWAIT, we just complete with -EAGAIN */
3018 if (req
->flags
& REQ_F_NOWAIT
)
3021 /* already tried, or we're doing O_DIRECT */
3022 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_WAITQ
))
3025 * just use poll if we can, and don't attempt if the fs doesn't
3026 * support callback based unlocks
3028 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3032 * If request type doesn't require req->io to defer in general,
3033 * we need to allocate it here
3035 if (!req
->io
&& __io_alloc_async_ctx(req
))
3038 ret
= kiocb_wait_page_queue_init(kiocb
, &req
->io
->rw
.wpq
,
3039 io_async_buf_func
, req
);
3041 io_get_req_task(req
);
3048 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3050 if (req
->file
->f_op
->read_iter
)
3051 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3052 return loop_rw_iter(READ
, req
->file
, &req
->rw
.kiocb
, iter
);
3055 static int io_read(struct io_kiocb
*req
, bool force_nonblock
,
3056 struct io_comp_state
*cs
)
3058 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3059 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3060 struct iov_iter iter
;
3062 ssize_t io_size
, ret
, ret2
;
3063 unsigned long nr_segs
;
3065 ret
= io_import_iovec(READ
, req
, &iovec
, &iter
, !force_nonblock
);
3069 req
->result
= io_size
;
3071 /* Ensure we clear previously set non-block flag */
3072 if (!force_nonblock
)
3073 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3075 /* If the file doesn't support async, just async punt */
3076 if (force_nonblock
&& !io_file_supports_async(req
->file
, READ
))
3079 iov_count
= iov_iter_count(&iter
);
3080 nr_segs
= iter
.nr_segs
;
3081 ret
= rw_verify_area(READ
, req
->file
, &kiocb
->ki_pos
, iov_count
);
3085 ret2
= io_iter_do_read(req
, &iter
);
3087 /* Catch -EAGAIN return for forced non-blocking submission */
3088 if (!force_nonblock
|| (ret2
!= -EAGAIN
&& ret2
!= -EIO
)) {
3089 kiocb_done(kiocb
, ret2
, cs
);
3091 iter
.count
= iov_count
;
3092 iter
.nr_segs
= nr_segs
;
3094 ret
= io_setup_async_rw(req
, io_size
, iovec
, inline_vecs
,
3098 /* it's copied and will be cleaned with ->io */
3100 /* if we can retry, do so with the callbacks armed */
3101 if (io_rw_should_retry(req
)) {
3102 ret2
= io_iter_do_read(req
, &iter
);
3103 if (ret2
== -EIOCBQUEUED
) {
3105 } else if (ret2
!= -EAGAIN
) {
3106 kiocb_done(kiocb
, ret2
, cs
);
3110 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3119 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
3120 bool force_nonblock
)
3124 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
3128 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3131 /* either don't need iovec imported or already have it */
3132 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
3134 return io_rw_prep_async(req
, WRITE
, force_nonblock
);
3137 static int io_write(struct io_kiocb
*req
, bool force_nonblock
,
3138 struct io_comp_state
*cs
)
3140 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3141 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3142 struct iov_iter iter
;
3144 ssize_t ret
, ret2
, io_size
;
3145 unsigned long nr_segs
;
3147 ret
= io_import_iovec(WRITE
, req
, &iovec
, &iter
, !force_nonblock
);
3151 req
->result
= io_size
;
3153 /* Ensure we clear previously set non-block flag */
3154 if (!force_nonblock
)
3155 req
->rw
.kiocb
.ki_flags
&= ~IOCB_NOWAIT
;
3157 /* If the file doesn't support async, just async punt */
3158 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3161 /* file path doesn't support NOWAIT for non-direct_IO */
3162 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3163 (req
->flags
& REQ_F_ISREG
))
3166 iov_count
= iov_iter_count(&iter
);
3167 nr_segs
= iter
.nr_segs
;
3168 ret
= rw_verify_area(WRITE
, req
->file
, &kiocb
->ki_pos
, iov_count
);
3173 * Open-code file_start_write here to grab freeze protection,
3174 * which will be released by another thread in
3175 * io_complete_rw(). Fool lockdep by telling it the lock got
3176 * released so that it doesn't complain about the held lock when
3177 * we return to userspace.
3179 if (req
->flags
& REQ_F_ISREG
) {
3180 __sb_start_write(file_inode(req
->file
)->i_sb
,
3181 SB_FREEZE_WRITE
, true);
3182 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3185 kiocb
->ki_flags
|= IOCB_WRITE
;
3187 if (req
->file
->f_op
->write_iter
)
3188 ret2
= call_write_iter(req
->file
, kiocb
, &iter
);
3190 ret2
= loop_rw_iter(WRITE
, req
->file
, kiocb
, &iter
);
3193 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3194 * retry them without IOCB_NOWAIT.
3196 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3198 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3199 kiocb_done(kiocb
, ret2
, cs
);
3201 iter
.count
= iov_count
;
3202 iter
.nr_segs
= nr_segs
;
3204 ret
= io_setup_async_rw(req
, io_size
, iovec
, inline_vecs
,
3208 /* it's copied and will be cleaned with ->io */
3218 static int __io_splice_prep(struct io_kiocb
*req
,
3219 const struct io_uring_sqe
*sqe
)
3221 struct io_splice
* sp
= &req
->splice
;
3222 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3225 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3227 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3231 sp
->len
= READ_ONCE(sqe
->len
);
3232 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3234 if (unlikely(sp
->flags
& ~valid_flags
))
3237 ret
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
), &sp
->file_in
,
3238 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3241 req
->flags
|= REQ_F_NEED_CLEANUP
;
3243 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3245 * Splice operation will be punted aync, and here need to
3246 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3248 io_req_init_async(req
);
3249 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3255 static int io_tee_prep(struct io_kiocb
*req
,
3256 const struct io_uring_sqe
*sqe
)
3258 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3260 return __io_splice_prep(req
, sqe
);
3263 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
3265 struct io_splice
*sp
= &req
->splice
;
3266 struct file
*in
= sp
->file_in
;
3267 struct file
*out
= sp
->file_out
;
3268 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3274 ret
= do_tee(in
, out
, sp
->len
, flags
);
3276 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3277 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3280 req_set_fail_links(req
);
3281 io_req_complete(req
, ret
);
3285 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3287 struct io_splice
* sp
= &req
->splice
;
3289 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3290 sp
->off_out
= READ_ONCE(sqe
->off
);
3291 return __io_splice_prep(req
, sqe
);
3294 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
3296 struct io_splice
*sp
= &req
->splice
;
3297 struct file
*in
= sp
->file_in
;
3298 struct file
*out
= sp
->file_out
;
3299 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3300 loff_t
*poff_in
, *poff_out
;
3306 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3307 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3310 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3312 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3313 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3316 req_set_fail_links(req
);
3317 io_req_complete(req
, ret
);
3322 * IORING_OP_NOP just posts a completion event, nothing else.
3324 static int io_nop(struct io_kiocb
*req
, struct io_comp_state
*cs
)
3326 struct io_ring_ctx
*ctx
= req
->ctx
;
3328 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3331 __io_req_complete(req
, 0, 0, cs
);
3335 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3337 struct io_ring_ctx
*ctx
= req
->ctx
;
3342 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3344 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3347 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3348 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3351 req
->sync
.off
= READ_ONCE(sqe
->off
);
3352 req
->sync
.len
= READ_ONCE(sqe
->len
);
3356 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
3358 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3361 /* fsync always requires a blocking context */
3365 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3366 end
> 0 ? end
: LLONG_MAX
,
3367 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3369 req_set_fail_links(req
);
3370 io_req_complete(req
, ret
);
3374 static int io_fallocate_prep(struct io_kiocb
*req
,
3375 const struct io_uring_sqe
*sqe
)
3377 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3379 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3382 req
->sync
.off
= READ_ONCE(sqe
->off
);
3383 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3384 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3388 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
3392 /* fallocate always requiring blocking context */
3395 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3398 req_set_fail_links(req
);
3399 io_req_complete(req
, ret
);
3403 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3405 const char __user
*fname
;
3408 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3410 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3412 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3415 /* open.how should be already initialised */
3416 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3417 req
->open
.how
.flags
|= O_LARGEFILE
;
3419 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3420 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3421 req
->open
.filename
= getname(fname
);
3422 if (IS_ERR(req
->open
.filename
)) {
3423 ret
= PTR_ERR(req
->open
.filename
);
3424 req
->open
.filename
= NULL
;
3427 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3428 req
->flags
|= REQ_F_NEED_CLEANUP
;
3432 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3436 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3438 mode
= READ_ONCE(sqe
->len
);
3439 flags
= READ_ONCE(sqe
->open_flags
);
3440 req
->open
.how
= build_open_how(flags
, mode
);
3441 return __io_openat_prep(req
, sqe
);
3444 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3446 struct open_how __user
*how
;
3450 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3452 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3453 len
= READ_ONCE(sqe
->len
);
3454 if (len
< OPEN_HOW_SIZE_VER0
)
3457 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3462 return __io_openat_prep(req
, sqe
);
3465 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
3467 struct open_flags op
;
3474 ret
= build_open_flags(&req
->open
.how
, &op
);
3478 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3482 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3485 ret
= PTR_ERR(file
);
3487 fsnotify_open(file
);
3488 fd_install(ret
, file
);
3491 putname(req
->open
.filename
);
3492 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3494 req_set_fail_links(req
);
3495 io_req_complete(req
, ret
);
3499 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
3501 return io_openat2(req
, force_nonblock
);
3504 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3505 const struct io_uring_sqe
*sqe
)
3507 struct io_provide_buf
*p
= &req
->pbuf
;
3510 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3513 tmp
= READ_ONCE(sqe
->fd
);
3514 if (!tmp
|| tmp
> USHRT_MAX
)
3517 memset(p
, 0, sizeof(*p
));
3519 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3523 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3524 int bgid
, unsigned nbufs
)
3528 /* shouldn't happen */
3532 /* the head kbuf is the list itself */
3533 while (!list_empty(&buf
->list
)) {
3534 struct io_buffer
*nxt
;
3536 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3537 list_del(&nxt
->list
);
3544 idr_remove(&ctx
->io_buffer_idr
, bgid
);
3549 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3550 struct io_comp_state
*cs
)
3552 struct io_provide_buf
*p
= &req
->pbuf
;
3553 struct io_ring_ctx
*ctx
= req
->ctx
;
3554 struct io_buffer
*head
;
3557 io_ring_submit_lock(ctx
, !force_nonblock
);
3559 lockdep_assert_held(&ctx
->uring_lock
);
3562 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3564 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3566 io_ring_submit_lock(ctx
, !force_nonblock
);
3568 req_set_fail_links(req
);
3569 __io_req_complete(req
, ret
, 0, cs
);
3573 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3574 const struct io_uring_sqe
*sqe
)
3576 struct io_provide_buf
*p
= &req
->pbuf
;
3579 if (sqe
->ioprio
|| sqe
->rw_flags
)
3582 tmp
= READ_ONCE(sqe
->fd
);
3583 if (!tmp
|| tmp
> USHRT_MAX
)
3586 p
->addr
= READ_ONCE(sqe
->addr
);
3587 p
->len
= READ_ONCE(sqe
->len
);
3589 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
3592 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3593 tmp
= READ_ONCE(sqe
->off
);
3594 if (tmp
> USHRT_MAX
)
3600 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3602 struct io_buffer
*buf
;
3603 u64 addr
= pbuf
->addr
;
3604 int i
, bid
= pbuf
->bid
;
3606 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3607 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3612 buf
->len
= pbuf
->len
;
3617 INIT_LIST_HEAD(&buf
->list
);
3620 list_add_tail(&buf
->list
, &(*head
)->list
);
3624 return i
? i
: -ENOMEM
;
3627 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3628 struct io_comp_state
*cs
)
3630 struct io_provide_buf
*p
= &req
->pbuf
;
3631 struct io_ring_ctx
*ctx
= req
->ctx
;
3632 struct io_buffer
*head
, *list
;
3635 io_ring_submit_lock(ctx
, !force_nonblock
);
3637 lockdep_assert_held(&ctx
->uring_lock
);
3639 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3641 ret
= io_add_buffers(p
, &head
);
3646 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
3649 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
3654 io_ring_submit_unlock(ctx
, !force_nonblock
);
3656 req_set_fail_links(req
);
3657 __io_req_complete(req
, ret
, 0, cs
);
3661 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
3662 const struct io_uring_sqe
*sqe
)
3664 #if defined(CONFIG_EPOLL)
3665 if (sqe
->ioprio
|| sqe
->buf_index
)
3667 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3670 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
3671 req
->epoll
.op
= READ_ONCE(sqe
->len
);
3672 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
3674 if (ep_op_has_event(req
->epoll
.op
)) {
3675 struct epoll_event __user
*ev
;
3677 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3678 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
3688 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
,
3689 struct io_comp_state
*cs
)
3691 #if defined(CONFIG_EPOLL)
3692 struct io_epoll
*ie
= &req
->epoll
;
3695 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
3696 if (force_nonblock
&& ret
== -EAGAIN
)
3700 req_set_fail_links(req
);
3701 __io_req_complete(req
, ret
, 0, cs
);
3708 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3710 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3711 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
3713 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3716 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
3717 req
->madvise
.len
= READ_ONCE(sqe
->len
);
3718 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3725 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
3727 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3728 struct io_madvise
*ma
= &req
->madvise
;
3734 ret
= do_madvise(ma
->addr
, ma
->len
, ma
->advice
);
3736 req_set_fail_links(req
);
3737 io_req_complete(req
, ret
);
3744 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3746 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
3748 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3751 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
3752 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
3753 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3757 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
3759 struct io_fadvise
*fa
= &req
->fadvise
;
3762 if (force_nonblock
) {
3763 switch (fa
->advice
) {
3764 case POSIX_FADV_NORMAL
:
3765 case POSIX_FADV_RANDOM
:
3766 case POSIX_FADV_SEQUENTIAL
:
3773 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
3775 req_set_fail_links(req
);
3776 io_req_complete(req
, ret
);
3780 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3782 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3784 if (sqe
->ioprio
|| sqe
->buf_index
)
3786 if (req
->flags
& REQ_F_FIXED_FILE
)
3789 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
3790 req
->statx
.mask
= READ_ONCE(sqe
->len
);
3791 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3792 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3793 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
3798 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
3800 struct io_statx
*ctx
= &req
->statx
;
3803 if (force_nonblock
) {
3804 /* only need file table for an actual valid fd */
3805 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
3806 req
->flags
|= REQ_F_NO_FILE_TABLE
;
3810 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
3814 req_set_fail_links(req
);
3815 io_req_complete(req
, ret
);
3819 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3822 * If we queue this for async, it must not be cancellable. That would
3823 * leave the 'file' in an undeterminate state, and here need to modify
3824 * io_wq_work.flags, so initialize io_wq_work firstly.
3826 io_req_init_async(req
);
3827 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
3829 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3831 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
3832 sqe
->rw_flags
|| sqe
->buf_index
)
3834 if (req
->flags
& REQ_F_FIXED_FILE
)
3837 req
->close
.fd
= READ_ONCE(sqe
->fd
);
3838 if ((req
->file
&& req
->file
->f_op
== &io_uring_fops
) ||
3839 req
->close
.fd
== req
->ctx
->ring_fd
)
3842 req
->close
.put_file
= NULL
;
3846 static int io_close(struct io_kiocb
*req
, bool force_nonblock
,
3847 struct io_comp_state
*cs
)
3849 struct io_close
*close
= &req
->close
;
3852 /* might be already done during nonblock submission */
3853 if (!close
->put_file
) {
3854 ret
= __close_fd_get_file(close
->fd
, &close
->put_file
);
3856 return (ret
== -ENOENT
) ? -EBADF
: ret
;
3859 /* if the file has a flush method, be safe and punt to async */
3860 if (close
->put_file
->f_op
->flush
&& force_nonblock
) {
3861 /* was never set, but play safe */
3862 req
->flags
&= ~REQ_F_NOWAIT
;
3863 /* avoid grabbing files - we don't need the files */
3864 req
->flags
|= REQ_F_NO_FILE_TABLE
;
3868 /* No ->flush() or already async, safely close from here */
3869 ret
= filp_close(close
->put_file
, req
->work
.files
);
3871 req_set_fail_links(req
);
3872 fput(close
->put_file
);
3873 close
->put_file
= NULL
;
3874 __io_req_complete(req
, ret
, 0, cs
);
3878 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3880 struct io_ring_ctx
*ctx
= req
->ctx
;
3885 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3887 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3890 req
->sync
.off
= READ_ONCE(sqe
->off
);
3891 req
->sync
.len
= READ_ONCE(sqe
->len
);
3892 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
3896 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
3900 /* sync_file_range always requires a blocking context */
3904 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
3907 req_set_fail_links(req
);
3908 io_req_complete(req
, ret
);
3912 #if defined(CONFIG_NET)
3913 static int io_setup_async_msg(struct io_kiocb
*req
,
3914 struct io_async_msghdr
*kmsg
)
3918 if (io_alloc_async_ctx(req
)) {
3919 if (kmsg
->iov
!= kmsg
->fast_iov
)
3923 req
->flags
|= REQ_F_NEED_CLEANUP
;
3924 memcpy(&req
->io
->msg
, kmsg
, sizeof(*kmsg
));
3928 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
3929 struct io_async_msghdr
*iomsg
)
3931 iomsg
->iov
= iomsg
->fast_iov
;
3932 iomsg
->msg
.msg_name
= &iomsg
->addr
;
3933 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
3934 req
->sr_msg
.msg_flags
, &iomsg
->iov
);
3937 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3939 struct io_sr_msg
*sr
= &req
->sr_msg
;
3940 struct io_async_ctx
*io
= req
->io
;
3943 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3946 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
3947 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3948 sr
->len
= READ_ONCE(sqe
->len
);
3950 #ifdef CONFIG_COMPAT
3951 if (req
->ctx
->compat
)
3952 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
3955 if (!io
|| req
->opcode
== IORING_OP_SEND
)
3957 /* iovec is already imported */
3958 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3961 ret
= io_sendmsg_copy_hdr(req
, &io
->msg
);
3963 req
->flags
|= REQ_F_NEED_CLEANUP
;
3967 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
3968 struct io_comp_state
*cs
)
3970 struct io_async_msghdr iomsg
, *kmsg
;
3971 struct socket
*sock
;
3975 sock
= sock_from_file(req
->file
, &ret
);
3976 if (unlikely(!sock
))
3980 kmsg
= &req
->io
->msg
;
3981 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
3982 /* if iov is set, it's allocated already */
3984 kmsg
->iov
= kmsg
->fast_iov
;
3985 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
3987 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
3993 flags
= req
->sr_msg
.msg_flags
;
3994 if (flags
& MSG_DONTWAIT
)
3995 req
->flags
|= REQ_F_NOWAIT
;
3996 else if (force_nonblock
)
3997 flags
|= MSG_DONTWAIT
;
3999 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4000 if (force_nonblock
&& ret
== -EAGAIN
)
4001 return io_setup_async_msg(req
, kmsg
);
4002 if (ret
== -ERESTARTSYS
)
4005 if (kmsg
->iov
!= kmsg
->fast_iov
)
4007 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4009 req_set_fail_links(req
);
4010 __io_req_complete(req
, ret
, 0, cs
);
4014 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4015 struct io_comp_state
*cs
)
4017 struct io_sr_msg
*sr
= &req
->sr_msg
;
4020 struct socket
*sock
;
4024 sock
= sock_from_file(req
->file
, &ret
);
4025 if (unlikely(!sock
))
4028 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4032 msg
.msg_name
= NULL
;
4033 msg
.msg_control
= NULL
;
4034 msg
.msg_controllen
= 0;
4035 msg
.msg_namelen
= 0;
4037 flags
= req
->sr_msg
.msg_flags
;
4038 if (flags
& MSG_DONTWAIT
)
4039 req
->flags
|= REQ_F_NOWAIT
;
4040 else if (force_nonblock
)
4041 flags
|= MSG_DONTWAIT
;
4043 msg
.msg_flags
= flags
;
4044 ret
= sock_sendmsg(sock
, &msg
);
4045 if (force_nonblock
&& ret
== -EAGAIN
)
4047 if (ret
== -ERESTARTSYS
)
4051 req_set_fail_links(req
);
4052 __io_req_complete(req
, ret
, 0, cs
);
4056 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4057 struct io_async_msghdr
*iomsg
)
4059 struct io_sr_msg
*sr
= &req
->sr_msg
;
4060 struct iovec __user
*uiov
;
4064 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4065 &iomsg
->uaddr
, &uiov
, &iov_len
);
4069 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4072 if (copy_from_user(iomsg
->iov
, uiov
, sizeof(*uiov
)))
4074 sr
->len
= iomsg
->iov
[0].iov_len
;
4075 iov_iter_init(&iomsg
->msg
.msg_iter
, READ
, iomsg
->iov
, 1,
4079 ret
= import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4080 &iomsg
->iov
, &iomsg
->msg
.msg_iter
);
4088 #ifdef CONFIG_COMPAT
4089 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4090 struct io_async_msghdr
*iomsg
)
4092 struct compat_msghdr __user
*msg_compat
;
4093 struct io_sr_msg
*sr
= &req
->sr_msg
;
4094 struct compat_iovec __user
*uiov
;
4099 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4100 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4105 uiov
= compat_ptr(ptr
);
4106 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4107 compat_ssize_t clen
;
4111 if (!access_ok(uiov
, sizeof(*uiov
)))
4113 if (__get_user(clen
, &uiov
->iov_len
))
4117 sr
->len
= iomsg
->iov
[0].iov_len
;
4120 ret
= compat_import_iovec(READ
, uiov
, len
, UIO_FASTIOV
,
4122 &iomsg
->msg
.msg_iter
);
4131 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4132 struct io_async_msghdr
*iomsg
)
4134 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4135 iomsg
->iov
= iomsg
->fast_iov
;
4137 #ifdef CONFIG_COMPAT
4138 if (req
->ctx
->compat
)
4139 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4142 return __io_recvmsg_copy_hdr(req
, iomsg
);
4145 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4148 struct io_sr_msg
*sr
= &req
->sr_msg
;
4149 struct io_buffer
*kbuf
;
4151 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4156 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4160 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4162 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4165 static int io_recvmsg_prep(struct io_kiocb
*req
,
4166 const struct io_uring_sqe
*sqe
)
4168 struct io_sr_msg
*sr
= &req
->sr_msg
;
4169 struct io_async_ctx
*io
= req
->io
;
4172 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4175 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4176 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4177 sr
->len
= READ_ONCE(sqe
->len
);
4178 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4180 #ifdef CONFIG_COMPAT
4181 if (req
->ctx
->compat
)
4182 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4185 if (!io
|| req
->opcode
== IORING_OP_RECV
)
4187 /* iovec is already imported */
4188 if (req
->flags
& REQ_F_NEED_CLEANUP
)
4191 ret
= io_recvmsg_copy_hdr(req
, &io
->msg
);
4193 req
->flags
|= REQ_F_NEED_CLEANUP
;
4197 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4198 struct io_comp_state
*cs
)
4200 struct io_async_msghdr iomsg
, *kmsg
;
4201 struct socket
*sock
;
4202 struct io_buffer
*kbuf
;
4204 int ret
, cflags
= 0;
4206 sock
= sock_from_file(req
->file
, &ret
);
4207 if (unlikely(!sock
))
4211 kmsg
= &req
->io
->msg
;
4212 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
4213 /* if iov is set, it's allocated already */
4215 kmsg
->iov
= kmsg
->fast_iov
;
4216 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4218 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4224 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4225 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4227 return PTR_ERR(kbuf
);
4228 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4229 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
4230 1, req
->sr_msg
.len
);
4233 flags
= req
->sr_msg
.msg_flags
;
4234 if (flags
& MSG_DONTWAIT
)
4235 req
->flags
|= REQ_F_NOWAIT
;
4236 else if (force_nonblock
)
4237 flags
|= MSG_DONTWAIT
;
4239 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4240 kmsg
->uaddr
, flags
);
4241 if (force_nonblock
&& ret
== -EAGAIN
)
4242 return io_setup_async_msg(req
, kmsg
);
4243 if (ret
== -ERESTARTSYS
)
4246 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4247 cflags
= io_put_recv_kbuf(req
);
4248 if (kmsg
->iov
!= kmsg
->fast_iov
)
4250 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4252 req_set_fail_links(req
);
4253 __io_req_complete(req
, ret
, cflags
, cs
);
4257 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4258 struct io_comp_state
*cs
)
4260 struct io_buffer
*kbuf
;
4261 struct io_sr_msg
*sr
= &req
->sr_msg
;
4263 void __user
*buf
= sr
->buf
;
4264 struct socket
*sock
;
4267 int ret
, cflags
= 0;
4269 sock
= sock_from_file(req
->file
, &ret
);
4270 if (unlikely(!sock
))
4273 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4274 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4276 return PTR_ERR(kbuf
);
4277 buf
= u64_to_user_ptr(kbuf
->addr
);
4280 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4284 msg
.msg_name
= NULL
;
4285 msg
.msg_control
= NULL
;
4286 msg
.msg_controllen
= 0;
4287 msg
.msg_namelen
= 0;
4288 msg
.msg_iocb
= NULL
;
4291 flags
= req
->sr_msg
.msg_flags
;
4292 if (flags
& MSG_DONTWAIT
)
4293 req
->flags
|= REQ_F_NOWAIT
;
4294 else if (force_nonblock
)
4295 flags
|= MSG_DONTWAIT
;
4297 ret
= sock_recvmsg(sock
, &msg
, flags
);
4298 if (force_nonblock
&& ret
== -EAGAIN
)
4300 if (ret
== -ERESTARTSYS
)
4303 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4304 cflags
= io_put_recv_kbuf(req
);
4306 req_set_fail_links(req
);
4307 __io_req_complete(req
, ret
, cflags
, cs
);
4311 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4313 struct io_accept
*accept
= &req
->accept
;
4315 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4317 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4320 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4321 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4322 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4323 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4327 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4328 struct io_comp_state
*cs
)
4330 struct io_accept
*accept
= &req
->accept
;
4331 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4334 if (req
->file
->f_flags
& O_NONBLOCK
)
4335 req
->flags
|= REQ_F_NOWAIT
;
4337 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4338 accept
->addr_len
, accept
->flags
,
4340 if (ret
== -EAGAIN
&& force_nonblock
)
4343 if (ret
== -ERESTARTSYS
)
4345 req_set_fail_links(req
);
4347 __io_req_complete(req
, ret
, 0, cs
);
4351 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4353 struct io_connect
*conn
= &req
->connect
;
4354 struct io_async_ctx
*io
= req
->io
;
4356 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4358 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4361 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4362 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4367 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4368 &io
->connect
.address
);
4371 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4372 struct io_comp_state
*cs
)
4374 struct io_async_ctx __io
, *io
;
4375 unsigned file_flags
;
4381 ret
= move_addr_to_kernel(req
->connect
.addr
,
4382 req
->connect
.addr_len
,
4383 &__io
.connect
.address
);
4389 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4391 ret
= __sys_connect_file(req
->file
, &io
->connect
.address
,
4392 req
->connect
.addr_len
, file_flags
);
4393 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4396 if (io_alloc_async_ctx(req
)) {
4400 memcpy(&req
->io
->connect
, &__io
.connect
, sizeof(__io
.connect
));
4403 if (ret
== -ERESTARTSYS
)
4407 req_set_fail_links(req
);
4408 __io_req_complete(req
, ret
, 0, cs
);
4411 #else /* !CONFIG_NET */
4412 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4417 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4418 struct io_comp_state
*cs
)
4423 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4424 struct io_comp_state
*cs
)
4429 static int io_recvmsg_prep(struct io_kiocb
*req
,
4430 const struct io_uring_sqe
*sqe
)
4435 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4436 struct io_comp_state
*cs
)
4441 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4442 struct io_comp_state
*cs
)
4447 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4452 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4453 struct io_comp_state
*cs
)
4458 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4463 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4464 struct io_comp_state
*cs
)
4468 #endif /* CONFIG_NET */
4470 struct io_poll_table
{
4471 struct poll_table_struct pt
;
4472 struct io_kiocb
*req
;
4476 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4477 __poll_t mask
, task_work_func_t func
)
4481 /* for instances that support it check for an event match first: */
4482 if (mask
&& !(mask
& poll
->events
))
4485 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4487 list_del_init(&poll
->wait
.entry
);
4490 init_task_work(&req
->task_work
, func
);
4492 * If this fails, then the task is exiting. When a task exits, the
4493 * work gets canceled, so just cancel this request as well instead
4494 * of executing it. We can't safely execute it anyway, as we may not
4495 * have the needed state needed for it anyway.
4497 ret
= io_req_task_work_add(req
, &req
->task_work
);
4498 if (unlikely(ret
)) {
4499 struct task_struct
*tsk
;
4501 WRITE_ONCE(poll
->canceled
, true);
4502 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
4503 task_work_add(tsk
, &req
->task_work
, 0);
4504 wake_up_process(tsk
);
4509 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4510 __acquires(&req
->ctx
->completion_lock
)
4512 struct io_ring_ctx
*ctx
= req
->ctx
;
4514 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4515 struct poll_table_struct pt
= { ._key
= poll
->events
};
4517 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4520 spin_lock_irq(&ctx
->completion_lock
);
4521 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4522 add_wait_queue(poll
->head
, &poll
->wait
);
4529 static void io_poll_remove_double(struct io_kiocb
*req
, void *data
)
4531 struct io_poll_iocb
*poll
= data
;
4533 lockdep_assert_held(&req
->ctx
->completion_lock
);
4535 if (poll
&& poll
->head
) {
4536 struct wait_queue_head
*head
= poll
->head
;
4538 spin_lock(&head
->lock
);
4539 list_del_init(&poll
->wait
.entry
);
4540 if (poll
->wait
.private)
4541 refcount_dec(&req
->refs
);
4543 spin_unlock(&head
->lock
);
4547 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4549 struct io_ring_ctx
*ctx
= req
->ctx
;
4551 io_poll_remove_double(req
, req
->io
);
4552 req
->poll
.done
= true;
4553 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
4554 io_commit_cqring(ctx
);
4557 static void io_poll_task_handler(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
4559 struct io_ring_ctx
*ctx
= req
->ctx
;
4561 if (io_poll_rewait(req
, &req
->poll
)) {
4562 spin_unlock_irq(&ctx
->completion_lock
);
4566 hash_del(&req
->hash_node
);
4567 io_poll_complete(req
, req
->result
, 0);
4568 req
->flags
|= REQ_F_COMP_LOCKED
;
4569 *nxt
= io_put_req_find_next(req
);
4570 spin_unlock_irq(&ctx
->completion_lock
);
4572 io_cqring_ev_posted(ctx
);
4575 static void io_poll_task_func(struct callback_head
*cb
)
4577 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4578 struct io_kiocb
*nxt
= NULL
;
4580 io_poll_task_handler(req
, &nxt
);
4582 __io_req_task_submit(nxt
);
4585 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4586 int sync
, void *key
)
4588 struct io_kiocb
*req
= wait
->private;
4589 struct io_poll_iocb
*poll
= req
->apoll
->double_poll
;
4590 __poll_t mask
= key_to_poll(key
);
4592 /* for instances that support it check for an event match first: */
4593 if (mask
&& !(mask
& poll
->events
))
4596 if (poll
&& poll
->head
) {
4599 spin_lock(&poll
->head
->lock
);
4600 done
= list_empty(&poll
->wait
.entry
);
4602 list_del_init(&poll
->wait
.entry
);
4603 spin_unlock(&poll
->head
->lock
);
4605 __io_async_wake(req
, poll
, mask
, io_poll_task_func
);
4607 refcount_dec(&req
->refs
);
4611 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
4612 wait_queue_func_t wake_func
)
4616 poll
->canceled
= false;
4617 poll
->events
= events
;
4618 INIT_LIST_HEAD(&poll
->wait
.entry
);
4619 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
4622 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
4623 struct wait_queue_head
*head
,
4624 struct io_poll_iocb
**poll_ptr
)
4626 struct io_kiocb
*req
= pt
->req
;
4629 * If poll->head is already set, it's because the file being polled
4630 * uses multiple waitqueues for poll handling (eg one for read, one
4631 * for write). Setup a separate io_poll_iocb if this happens.
4633 if (unlikely(poll
->head
)) {
4634 /* already have a 2nd entry, fail a third attempt */
4636 pt
->error
= -EINVAL
;
4639 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
4641 pt
->error
= -ENOMEM
;
4644 io_init_poll_iocb(poll
, req
->poll
.events
, io_poll_double_wake
);
4645 refcount_inc(&req
->refs
);
4646 poll
->wait
.private = req
;
4653 if (poll
->events
& EPOLLEXCLUSIVE
)
4654 add_wait_queue_exclusive(head
, &poll
->wait
);
4656 add_wait_queue(head
, &poll
->wait
);
4659 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4660 struct poll_table_struct
*p
)
4662 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4663 struct async_poll
*apoll
= pt
->req
->apoll
;
4665 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
4668 static void io_async_task_func(struct callback_head
*cb
)
4670 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4671 struct async_poll
*apoll
= req
->apoll
;
4672 struct io_ring_ctx
*ctx
= req
->ctx
;
4674 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
4676 if (io_poll_rewait(req
, &apoll
->poll
)) {
4677 spin_unlock_irq(&ctx
->completion_lock
);
4681 /* If req is still hashed, it cannot have been canceled. Don't check. */
4682 if (hash_hashed(&req
->hash_node
))
4683 hash_del(&req
->hash_node
);
4685 io_poll_remove_double(req
, apoll
->double_poll
);
4686 spin_unlock_irq(&ctx
->completion_lock
);
4688 if (!READ_ONCE(apoll
->poll
.canceled
))
4689 __io_req_task_submit(req
);
4691 __io_req_task_cancel(req
, -ECANCELED
);
4693 kfree(apoll
->double_poll
);
4697 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4700 struct io_kiocb
*req
= wait
->private;
4701 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
4703 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
4706 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
4709 static void io_poll_req_insert(struct io_kiocb
*req
)
4711 struct io_ring_ctx
*ctx
= req
->ctx
;
4712 struct hlist_head
*list
;
4714 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
4715 hlist_add_head(&req
->hash_node
, list
);
4718 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
4719 struct io_poll_iocb
*poll
,
4720 struct io_poll_table
*ipt
, __poll_t mask
,
4721 wait_queue_func_t wake_func
)
4722 __acquires(&ctx
->completion_lock
)
4724 struct io_ring_ctx
*ctx
= req
->ctx
;
4725 bool cancel
= false;
4727 io_init_poll_iocb(poll
, mask
, wake_func
);
4728 poll
->file
= req
->file
;
4729 poll
->wait
.private = req
;
4731 ipt
->pt
._key
= mask
;
4733 ipt
->error
= -EINVAL
;
4735 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
4737 spin_lock_irq(&ctx
->completion_lock
);
4738 if (likely(poll
->head
)) {
4739 spin_lock(&poll
->head
->lock
);
4740 if (unlikely(list_empty(&poll
->wait
.entry
))) {
4746 if (mask
|| ipt
->error
)
4747 list_del_init(&poll
->wait
.entry
);
4749 WRITE_ONCE(poll
->canceled
, true);
4750 else if (!poll
->done
) /* actually waiting for an event */
4751 io_poll_req_insert(req
);
4752 spin_unlock(&poll
->head
->lock
);
4758 static bool io_arm_poll_handler(struct io_kiocb
*req
)
4760 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
4761 struct io_ring_ctx
*ctx
= req
->ctx
;
4762 struct async_poll
*apoll
;
4763 struct io_poll_table ipt
;
4766 if (!req
->file
|| !file_can_poll(req
->file
))
4768 if (req
->flags
& REQ_F_POLLED
)
4770 if (!def
->pollin
&& !def
->pollout
)
4773 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
4774 if (unlikely(!apoll
))
4776 apoll
->double_poll
= NULL
;
4778 req
->flags
|= REQ_F_POLLED
;
4779 io_get_req_task(req
);
4781 INIT_HLIST_NODE(&req
->hash_node
);
4785 mask
|= POLLIN
| POLLRDNORM
;
4787 mask
|= POLLOUT
| POLLWRNORM
;
4788 mask
|= POLLERR
| POLLPRI
;
4790 ipt
.pt
._qproc
= io_async_queue_proc
;
4792 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
4795 io_poll_remove_double(req
, apoll
->double_poll
);
4796 spin_unlock_irq(&ctx
->completion_lock
);
4797 kfree(apoll
->double_poll
);
4801 spin_unlock_irq(&ctx
->completion_lock
);
4802 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
4803 apoll
->poll
.events
);
4807 static bool __io_poll_remove_one(struct io_kiocb
*req
,
4808 struct io_poll_iocb
*poll
)
4810 bool do_complete
= false;
4812 spin_lock(&poll
->head
->lock
);
4813 WRITE_ONCE(poll
->canceled
, true);
4814 if (!list_empty(&poll
->wait
.entry
)) {
4815 list_del_init(&poll
->wait
.entry
);
4818 spin_unlock(&poll
->head
->lock
);
4819 hash_del(&req
->hash_node
);
4823 static bool io_poll_remove_one(struct io_kiocb
*req
)
4827 if (req
->opcode
== IORING_OP_POLL_ADD
) {
4828 io_poll_remove_double(req
, req
->io
);
4829 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
4831 struct async_poll
*apoll
= req
->apoll
;
4833 io_poll_remove_double(req
, apoll
->double_poll
);
4835 /* non-poll requests have submit ref still */
4836 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
4839 kfree(apoll
->double_poll
);
4845 io_cqring_fill_event(req
, -ECANCELED
);
4846 io_commit_cqring(req
->ctx
);
4847 req
->flags
|= REQ_F_COMP_LOCKED
;
4854 static void io_poll_remove_all(struct io_ring_ctx
*ctx
)
4856 struct hlist_node
*tmp
;
4857 struct io_kiocb
*req
;
4860 spin_lock_irq(&ctx
->completion_lock
);
4861 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
4862 struct hlist_head
*list
;
4864 list
= &ctx
->cancel_hash
[i
];
4865 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
)
4866 posted
+= io_poll_remove_one(req
);
4868 spin_unlock_irq(&ctx
->completion_lock
);
4871 io_cqring_ev_posted(ctx
);
4874 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
4876 struct hlist_head
*list
;
4877 struct io_kiocb
*req
;
4879 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
4880 hlist_for_each_entry(req
, list
, hash_node
) {
4881 if (sqe_addr
!= req
->user_data
)
4883 if (io_poll_remove_one(req
))
4891 static int io_poll_remove_prep(struct io_kiocb
*req
,
4892 const struct io_uring_sqe
*sqe
)
4894 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4896 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
4900 req
->poll
.addr
= READ_ONCE(sqe
->addr
);
4905 * Find a running poll command that matches one specified in sqe->addr,
4906 * and remove it if found.
4908 static int io_poll_remove(struct io_kiocb
*req
)
4910 struct io_ring_ctx
*ctx
= req
->ctx
;
4914 addr
= req
->poll
.addr
;
4915 spin_lock_irq(&ctx
->completion_lock
);
4916 ret
= io_poll_cancel(ctx
, addr
);
4917 spin_unlock_irq(&ctx
->completion_lock
);
4920 req_set_fail_links(req
);
4921 io_req_complete(req
, ret
);
4925 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4928 struct io_kiocb
*req
= wait
->private;
4929 struct io_poll_iocb
*poll
= &req
->poll
;
4931 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
4934 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4935 struct poll_table_struct
*p
)
4937 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4939 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->io
);
4942 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4944 struct io_poll_iocb
*poll
= &req
->poll
;
4947 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4949 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
4954 events
= READ_ONCE(sqe
->poll32_events
);
4956 events
= swahw32(events
);
4958 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
4959 (events
& EPOLLEXCLUSIVE
);
4961 io_get_req_task(req
);
4965 static int io_poll_add(struct io_kiocb
*req
)
4967 struct io_poll_iocb
*poll
= &req
->poll
;
4968 struct io_ring_ctx
*ctx
= req
->ctx
;
4969 struct io_poll_table ipt
;
4972 INIT_HLIST_NODE(&req
->hash_node
);
4973 ipt
.pt
._qproc
= io_poll_queue_proc
;
4975 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
4978 if (mask
) { /* no async, we'd stolen it */
4980 io_poll_complete(req
, mask
, 0);
4982 spin_unlock_irq(&ctx
->completion_lock
);
4985 io_cqring_ev_posted(ctx
);
4991 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
4993 struct io_timeout_data
*data
= container_of(timer
,
4994 struct io_timeout_data
, timer
);
4995 struct io_kiocb
*req
= data
->req
;
4996 struct io_ring_ctx
*ctx
= req
->ctx
;
4997 unsigned long flags
;
4999 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5000 atomic_set(&req
->ctx
->cq_timeouts
,
5001 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5004 * We could be racing with timeout deletion. If the list is empty,
5005 * then timeout lookup already found it and will be handling it.
5007 if (!list_empty(&req
->timeout
.list
))
5008 list_del_init(&req
->timeout
.list
);
5010 io_cqring_fill_event(req
, -ETIME
);
5011 io_commit_cqring(ctx
);
5012 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5014 io_cqring_ev_posted(ctx
);
5015 req_set_fail_links(req
);
5017 return HRTIMER_NORESTART
;
5020 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5022 struct io_kiocb
*req
;
5025 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5026 if (user_data
== req
->user_data
) {
5027 list_del_init(&req
->timeout
.list
);
5036 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
5040 req_set_fail_links(req
);
5041 io_cqring_fill_event(req
, -ECANCELED
);
5046 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5047 const struct io_uring_sqe
*sqe
)
5049 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5051 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5053 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5056 req
->timeout
.addr
= READ_ONCE(sqe
->addr
);
5057 req
->timeout
.flags
= READ_ONCE(sqe
->timeout_flags
);
5058 if (req
->timeout
.flags
)
5065 * Remove or update an existing timeout command
5067 static int io_timeout_remove(struct io_kiocb
*req
)
5069 struct io_ring_ctx
*ctx
= req
->ctx
;
5072 spin_lock_irq(&ctx
->completion_lock
);
5073 ret
= io_timeout_cancel(ctx
, req
->timeout
.addr
);
5075 io_cqring_fill_event(req
, ret
);
5076 io_commit_cqring(ctx
);
5077 spin_unlock_irq(&ctx
->completion_lock
);
5078 io_cqring_ev_posted(ctx
);
5080 req_set_fail_links(req
);
5085 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5086 bool is_timeout_link
)
5088 struct io_timeout_data
*data
;
5090 u32 off
= READ_ONCE(sqe
->off
);
5092 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5094 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5096 if (off
&& is_timeout_link
)
5098 flags
= READ_ONCE(sqe
->timeout_flags
);
5099 if (flags
& ~IORING_TIMEOUT_ABS
)
5102 req
->timeout
.off
= off
;
5104 if (!req
->io
&& io_alloc_async_ctx(req
))
5107 data
= &req
->io
->timeout
;
5110 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5113 if (flags
& IORING_TIMEOUT_ABS
)
5114 data
->mode
= HRTIMER_MODE_ABS
;
5116 data
->mode
= HRTIMER_MODE_REL
;
5118 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5122 static int io_timeout(struct io_kiocb
*req
)
5124 struct io_ring_ctx
*ctx
= req
->ctx
;
5125 struct io_timeout_data
*data
= &req
->io
->timeout
;
5126 struct list_head
*entry
;
5127 u32 tail
, off
= req
->timeout
.off
;
5129 spin_lock_irq(&ctx
->completion_lock
);
5132 * sqe->off holds how many events that need to occur for this
5133 * timeout event to be satisfied. If it isn't set, then this is
5134 * a pure timeout request, sequence isn't used.
5136 if (io_is_timeout_noseq(req
)) {
5137 entry
= ctx
->timeout_list
.prev
;
5141 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5142 req
->timeout
.target_seq
= tail
+ off
;
5145 * Insertion sort, ensuring the first entry in the list is always
5146 * the one we need first.
5148 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5149 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5152 if (io_is_timeout_noseq(nxt
))
5154 /* nxt.seq is behind @tail, otherwise would've been completed */
5155 if (off
>= nxt
->timeout
.target_seq
- tail
)
5159 list_add(&req
->timeout
.list
, entry
);
5160 data
->timer
.function
= io_timeout_fn
;
5161 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5162 spin_unlock_irq(&ctx
->completion_lock
);
5166 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5168 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5170 return req
->user_data
== (unsigned long) data
;
5173 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5175 enum io_wq_cancel cancel_ret
;
5178 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5179 switch (cancel_ret
) {
5180 case IO_WQ_CANCEL_OK
:
5183 case IO_WQ_CANCEL_RUNNING
:
5186 case IO_WQ_CANCEL_NOTFOUND
:
5194 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5195 struct io_kiocb
*req
, __u64 sqe_addr
,
5198 unsigned long flags
;
5201 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5202 if (ret
!= -ENOENT
) {
5203 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5207 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5208 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5211 ret
= io_poll_cancel(ctx
, sqe_addr
);
5215 io_cqring_fill_event(req
, ret
);
5216 io_commit_cqring(ctx
);
5217 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5218 io_cqring_ev_posted(ctx
);
5221 req_set_fail_links(req
);
5225 static int io_async_cancel_prep(struct io_kiocb
*req
,
5226 const struct io_uring_sqe
*sqe
)
5228 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5230 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5232 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5235 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5239 static int io_async_cancel(struct io_kiocb
*req
)
5241 struct io_ring_ctx
*ctx
= req
->ctx
;
5243 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
5247 static int io_files_update_prep(struct io_kiocb
*req
,
5248 const struct io_uring_sqe
*sqe
)
5250 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5252 if (sqe
->ioprio
|| sqe
->rw_flags
)
5255 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
5256 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
5257 if (!req
->files_update
.nr_args
)
5259 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
5263 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
,
5264 struct io_comp_state
*cs
)
5266 struct io_ring_ctx
*ctx
= req
->ctx
;
5267 struct io_uring_files_update up
;
5273 up
.offset
= req
->files_update
.offset
;
5274 up
.fds
= req
->files_update
.arg
;
5276 mutex_lock(&ctx
->uring_lock
);
5277 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
5278 mutex_unlock(&ctx
->uring_lock
);
5281 req_set_fail_links(req
);
5282 __io_req_complete(req
, ret
, 0, cs
);
5286 static int io_req_defer_prep(struct io_kiocb
*req
,
5287 const struct io_uring_sqe
*sqe
)
5294 if (io_alloc_async_ctx(req
))
5296 ret
= io_prep_work_files(req
);
5300 switch (req
->opcode
) {
5303 case IORING_OP_READV
:
5304 case IORING_OP_READ_FIXED
:
5305 case IORING_OP_READ
:
5306 ret
= io_read_prep(req
, sqe
, true);
5308 case IORING_OP_WRITEV
:
5309 case IORING_OP_WRITE_FIXED
:
5310 case IORING_OP_WRITE
:
5311 ret
= io_write_prep(req
, sqe
, true);
5313 case IORING_OP_POLL_ADD
:
5314 ret
= io_poll_add_prep(req
, sqe
);
5316 case IORING_OP_POLL_REMOVE
:
5317 ret
= io_poll_remove_prep(req
, sqe
);
5319 case IORING_OP_FSYNC
:
5320 ret
= io_prep_fsync(req
, sqe
);
5322 case IORING_OP_SYNC_FILE_RANGE
:
5323 ret
= io_prep_sfr(req
, sqe
);
5325 case IORING_OP_SENDMSG
:
5326 case IORING_OP_SEND
:
5327 ret
= io_sendmsg_prep(req
, sqe
);
5329 case IORING_OP_RECVMSG
:
5330 case IORING_OP_RECV
:
5331 ret
= io_recvmsg_prep(req
, sqe
);
5333 case IORING_OP_CONNECT
:
5334 ret
= io_connect_prep(req
, sqe
);
5336 case IORING_OP_TIMEOUT
:
5337 ret
= io_timeout_prep(req
, sqe
, false);
5339 case IORING_OP_TIMEOUT_REMOVE
:
5340 ret
= io_timeout_remove_prep(req
, sqe
);
5342 case IORING_OP_ASYNC_CANCEL
:
5343 ret
= io_async_cancel_prep(req
, sqe
);
5345 case IORING_OP_LINK_TIMEOUT
:
5346 ret
= io_timeout_prep(req
, sqe
, true);
5348 case IORING_OP_ACCEPT
:
5349 ret
= io_accept_prep(req
, sqe
);
5351 case IORING_OP_FALLOCATE
:
5352 ret
= io_fallocate_prep(req
, sqe
);
5354 case IORING_OP_OPENAT
:
5355 ret
= io_openat_prep(req
, sqe
);
5357 case IORING_OP_CLOSE
:
5358 ret
= io_close_prep(req
, sqe
);
5360 case IORING_OP_FILES_UPDATE
:
5361 ret
= io_files_update_prep(req
, sqe
);
5363 case IORING_OP_STATX
:
5364 ret
= io_statx_prep(req
, sqe
);
5366 case IORING_OP_FADVISE
:
5367 ret
= io_fadvise_prep(req
, sqe
);
5369 case IORING_OP_MADVISE
:
5370 ret
= io_madvise_prep(req
, sqe
);
5372 case IORING_OP_OPENAT2
:
5373 ret
= io_openat2_prep(req
, sqe
);
5375 case IORING_OP_EPOLL_CTL
:
5376 ret
= io_epoll_ctl_prep(req
, sqe
);
5378 case IORING_OP_SPLICE
:
5379 ret
= io_splice_prep(req
, sqe
);
5381 case IORING_OP_PROVIDE_BUFFERS
:
5382 ret
= io_provide_buffers_prep(req
, sqe
);
5384 case IORING_OP_REMOVE_BUFFERS
:
5385 ret
= io_remove_buffers_prep(req
, sqe
);
5388 ret
= io_tee_prep(req
, sqe
);
5391 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5400 static u32
io_get_sequence(struct io_kiocb
*req
)
5402 struct io_kiocb
*pos
;
5403 struct io_ring_ctx
*ctx
= req
->ctx
;
5404 u32 total_submitted
, nr_reqs
= 1;
5406 if (req
->flags
& REQ_F_LINK_HEAD
)
5407 list_for_each_entry(pos
, &req
->link_list
, link_list
)
5410 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5411 return total_submitted
- nr_reqs
;
5414 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5416 struct io_ring_ctx
*ctx
= req
->ctx
;
5417 struct io_defer_entry
*de
;
5421 /* Still need defer if there is pending req in defer list. */
5422 if (likely(list_empty_careful(&ctx
->defer_list
) &&
5423 !(req
->flags
& REQ_F_IO_DRAIN
)))
5426 seq
= io_get_sequence(req
);
5427 /* Still a chance to pass the sequence check */
5428 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
5432 ret
= io_req_defer_prep(req
, sqe
);
5436 io_prep_async_link(req
);
5437 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
5441 spin_lock_irq(&ctx
->completion_lock
);
5442 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
5443 spin_unlock_irq(&ctx
->completion_lock
);
5445 io_queue_async_work(req
);
5446 return -EIOCBQUEUED
;
5449 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5452 list_add_tail(&de
->list
, &ctx
->defer_list
);
5453 spin_unlock_irq(&ctx
->completion_lock
);
5454 return -EIOCBQUEUED
;
5457 static void __io_clean_op(struct io_kiocb
*req
)
5459 struct io_async_ctx
*io
= req
->io
;
5461 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
5462 switch (req
->opcode
) {
5463 case IORING_OP_READV
:
5464 case IORING_OP_READ_FIXED
:
5465 case IORING_OP_READ
:
5466 kfree((void *)(unsigned long)req
->rw
.addr
);
5468 case IORING_OP_RECVMSG
:
5469 case IORING_OP_RECV
:
5470 kfree(req
->sr_msg
.kbuf
);
5473 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
5476 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
5477 switch (req
->opcode
) {
5478 case IORING_OP_READV
:
5479 case IORING_OP_READ_FIXED
:
5480 case IORING_OP_READ
:
5481 case IORING_OP_WRITEV
:
5482 case IORING_OP_WRITE_FIXED
:
5483 case IORING_OP_WRITE
:
5484 if (io
->rw
.iov
!= io
->rw
.fast_iov
)
5487 case IORING_OP_RECVMSG
:
5488 case IORING_OP_SENDMSG
:
5489 if (io
->msg
.iov
!= io
->msg
.fast_iov
)
5492 case IORING_OP_SPLICE
:
5494 io_put_file(req
, req
->splice
.file_in
,
5495 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
5498 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5502 static int io_issue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5503 bool force_nonblock
, struct io_comp_state
*cs
)
5505 struct io_ring_ctx
*ctx
= req
->ctx
;
5508 switch (req
->opcode
) {
5510 ret
= io_nop(req
, cs
);
5512 case IORING_OP_READV
:
5513 case IORING_OP_READ_FIXED
:
5514 case IORING_OP_READ
:
5516 ret
= io_read_prep(req
, sqe
, force_nonblock
);
5520 ret
= io_read(req
, force_nonblock
, cs
);
5522 case IORING_OP_WRITEV
:
5523 case IORING_OP_WRITE_FIXED
:
5524 case IORING_OP_WRITE
:
5526 ret
= io_write_prep(req
, sqe
, force_nonblock
);
5530 ret
= io_write(req
, force_nonblock
, cs
);
5532 case IORING_OP_FSYNC
:
5534 ret
= io_prep_fsync(req
, sqe
);
5538 ret
= io_fsync(req
, force_nonblock
);
5540 case IORING_OP_POLL_ADD
:
5542 ret
= io_poll_add_prep(req
, sqe
);
5546 ret
= io_poll_add(req
);
5548 case IORING_OP_POLL_REMOVE
:
5550 ret
= io_poll_remove_prep(req
, sqe
);
5554 ret
= io_poll_remove(req
);
5556 case IORING_OP_SYNC_FILE_RANGE
:
5558 ret
= io_prep_sfr(req
, sqe
);
5562 ret
= io_sync_file_range(req
, force_nonblock
);
5564 case IORING_OP_SENDMSG
:
5565 case IORING_OP_SEND
:
5567 ret
= io_sendmsg_prep(req
, sqe
);
5571 if (req
->opcode
== IORING_OP_SENDMSG
)
5572 ret
= io_sendmsg(req
, force_nonblock
, cs
);
5574 ret
= io_send(req
, force_nonblock
, cs
);
5576 case IORING_OP_RECVMSG
:
5577 case IORING_OP_RECV
:
5579 ret
= io_recvmsg_prep(req
, sqe
);
5583 if (req
->opcode
== IORING_OP_RECVMSG
)
5584 ret
= io_recvmsg(req
, force_nonblock
, cs
);
5586 ret
= io_recv(req
, force_nonblock
, cs
);
5588 case IORING_OP_TIMEOUT
:
5590 ret
= io_timeout_prep(req
, sqe
, false);
5594 ret
= io_timeout(req
);
5596 case IORING_OP_TIMEOUT_REMOVE
:
5598 ret
= io_timeout_remove_prep(req
, sqe
);
5602 ret
= io_timeout_remove(req
);
5604 case IORING_OP_ACCEPT
:
5606 ret
= io_accept_prep(req
, sqe
);
5610 ret
= io_accept(req
, force_nonblock
, cs
);
5612 case IORING_OP_CONNECT
:
5614 ret
= io_connect_prep(req
, sqe
);
5618 ret
= io_connect(req
, force_nonblock
, cs
);
5620 case IORING_OP_ASYNC_CANCEL
:
5622 ret
= io_async_cancel_prep(req
, sqe
);
5626 ret
= io_async_cancel(req
);
5628 case IORING_OP_FALLOCATE
:
5630 ret
= io_fallocate_prep(req
, sqe
);
5634 ret
= io_fallocate(req
, force_nonblock
);
5636 case IORING_OP_OPENAT
:
5638 ret
= io_openat_prep(req
, sqe
);
5642 ret
= io_openat(req
, force_nonblock
);
5644 case IORING_OP_CLOSE
:
5646 ret
= io_close_prep(req
, sqe
);
5650 ret
= io_close(req
, force_nonblock
, cs
);
5652 case IORING_OP_FILES_UPDATE
:
5654 ret
= io_files_update_prep(req
, sqe
);
5658 ret
= io_files_update(req
, force_nonblock
, cs
);
5660 case IORING_OP_STATX
:
5662 ret
= io_statx_prep(req
, sqe
);
5666 ret
= io_statx(req
, force_nonblock
);
5668 case IORING_OP_FADVISE
:
5670 ret
= io_fadvise_prep(req
, sqe
);
5674 ret
= io_fadvise(req
, force_nonblock
);
5676 case IORING_OP_MADVISE
:
5678 ret
= io_madvise_prep(req
, sqe
);
5682 ret
= io_madvise(req
, force_nonblock
);
5684 case IORING_OP_OPENAT2
:
5686 ret
= io_openat2_prep(req
, sqe
);
5690 ret
= io_openat2(req
, force_nonblock
);
5692 case IORING_OP_EPOLL_CTL
:
5694 ret
= io_epoll_ctl_prep(req
, sqe
);
5698 ret
= io_epoll_ctl(req
, force_nonblock
, cs
);
5700 case IORING_OP_SPLICE
:
5702 ret
= io_splice_prep(req
, sqe
);
5706 ret
= io_splice(req
, force_nonblock
);
5708 case IORING_OP_PROVIDE_BUFFERS
:
5710 ret
= io_provide_buffers_prep(req
, sqe
);
5714 ret
= io_provide_buffers(req
, force_nonblock
, cs
);
5716 case IORING_OP_REMOVE_BUFFERS
:
5718 ret
= io_remove_buffers_prep(req
, sqe
);
5722 ret
= io_remove_buffers(req
, force_nonblock
, cs
);
5726 ret
= io_tee_prep(req
, sqe
);
5730 ret
= io_tee(req
, force_nonblock
);
5740 /* If the op doesn't have a file, we're not polling for it */
5741 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
5742 const bool in_async
= io_wq_current_is_worker();
5744 /* workqueue context doesn't hold uring_lock, grab it now */
5746 mutex_lock(&ctx
->uring_lock
);
5748 io_iopoll_req_issued(req
);
5751 mutex_unlock(&ctx
->uring_lock
);
5757 static struct io_wq_work
*io_wq_submit_work(struct io_wq_work
*work
)
5759 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5760 struct io_kiocb
*timeout
;
5763 timeout
= io_prep_linked_timeout(req
);
5765 io_queue_linked_timeout(timeout
);
5767 /* if NO_CANCEL is set, we must still run the work */
5768 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
5769 IO_WQ_WORK_CANCEL
) {
5775 ret
= io_issue_sqe(req
, NULL
, false, NULL
);
5777 * We can get EAGAIN for polled IO even though we're
5778 * forcing a sync submission from here, since we can't
5779 * wait for request slots on the block side.
5788 req_set_fail_links(req
);
5789 io_req_complete(req
, ret
);
5792 return io_steal_work(req
);
5795 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
5798 struct fixed_file_table
*table
;
5800 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
5801 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
5804 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
5805 int fd
, struct file
**out_file
, bool fixed
)
5807 struct io_ring_ctx
*ctx
= req
->ctx
;
5811 if (unlikely(!ctx
->file_data
||
5812 (unsigned) fd
>= ctx
->nr_user_files
))
5814 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
5815 file
= io_file_from_index(ctx
, fd
);
5817 req
->fixed_file_refs
= ctx
->file_data
->cur_refs
;
5818 percpu_ref_get(req
->fixed_file_refs
);
5821 trace_io_uring_file_get(ctx
, fd
);
5822 file
= __io_file_get(state
, fd
);
5825 if (file
|| io_op_defs
[req
->opcode
].needs_file_no_error
) {
5832 static int io_req_set_file(struct io_submit_state
*state
, struct io_kiocb
*req
,
5837 fixed
= (req
->flags
& REQ_F_FIXED_FILE
) != 0;
5838 if (unlikely(!fixed
&& io_async_submit(req
->ctx
)))
5841 return io_file_get(state
, req
, fd
, &req
->file
, fixed
);
5844 static int io_grab_files(struct io_kiocb
*req
)
5847 struct io_ring_ctx
*ctx
= req
->ctx
;
5849 io_req_init_async(req
);
5851 if (req
->work
.files
|| (req
->flags
& REQ_F_NO_FILE_TABLE
))
5853 if (!ctx
->ring_file
)
5857 spin_lock_irq(&ctx
->inflight_lock
);
5859 * We use the f_ops->flush() handler to ensure that we can flush
5860 * out work accessing these files if the fd is closed. Check if
5861 * the fd has changed since we started down this path, and disallow
5862 * this operation if it has.
5864 if (fcheck(ctx
->ring_fd
) == ctx
->ring_file
) {
5865 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
5866 req
->flags
|= REQ_F_INFLIGHT
;
5867 req
->work
.files
= current
->files
;
5870 spin_unlock_irq(&ctx
->inflight_lock
);
5876 static inline int io_prep_work_files(struct io_kiocb
*req
)
5878 if (!io_op_defs
[req
->opcode
].file_table
)
5880 return io_grab_files(req
);
5883 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
5885 struct io_timeout_data
*data
= container_of(timer
,
5886 struct io_timeout_data
, timer
);
5887 struct io_kiocb
*req
= data
->req
;
5888 struct io_ring_ctx
*ctx
= req
->ctx
;
5889 struct io_kiocb
*prev
= NULL
;
5890 unsigned long flags
;
5892 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5895 * We don't expect the list to be empty, that will only happen if we
5896 * race with the completion of the linked work.
5898 if (!list_empty(&req
->link_list
)) {
5899 prev
= list_entry(req
->link_list
.prev
, struct io_kiocb
,
5901 if (refcount_inc_not_zero(&prev
->refs
)) {
5902 list_del_init(&req
->link_list
);
5903 prev
->flags
&= ~REQ_F_LINK_TIMEOUT
;
5908 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5911 req_set_fail_links(prev
);
5912 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
5915 io_req_complete(req
, -ETIME
);
5917 return HRTIMER_NORESTART
;
5920 static void io_queue_linked_timeout(struct io_kiocb
*req
)
5922 struct io_ring_ctx
*ctx
= req
->ctx
;
5925 * If the list is now empty, then our linked request finished before
5926 * we got a chance to setup the timer
5928 spin_lock_irq(&ctx
->completion_lock
);
5929 if (!list_empty(&req
->link_list
)) {
5930 struct io_timeout_data
*data
= &req
->io
->timeout
;
5932 data
->timer
.function
= io_link_timeout_fn
;
5933 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
5936 spin_unlock_irq(&ctx
->completion_lock
);
5938 /* drop submission reference */
5942 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
5944 struct io_kiocb
*nxt
;
5946 if (!(req
->flags
& REQ_F_LINK_HEAD
))
5948 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
5951 nxt
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
5953 if (!nxt
|| nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
5956 req
->flags
|= REQ_F_LINK_TIMEOUT
;
5960 static void __io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5961 struct io_comp_state
*cs
)
5963 struct io_kiocb
*linked_timeout
;
5964 struct io_kiocb
*nxt
;
5965 const struct cred
*old_creds
= NULL
;
5969 linked_timeout
= io_prep_linked_timeout(req
);
5971 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) && req
->work
.creds
&&
5972 req
->work
.creds
!= current_cred()) {
5974 revert_creds(old_creds
);
5975 if (old_creds
== req
->work
.creds
)
5976 old_creds
= NULL
; /* restored original creds */
5978 old_creds
= override_creds(req
->work
.creds
);
5981 ret
= io_issue_sqe(req
, sqe
, true, cs
);
5984 * We async punt it if the file wasn't marked NOWAIT, or if the file
5985 * doesn't support non-blocking read/write attempts
5987 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
5988 if (!io_arm_poll_handler(req
)) {
5990 ret
= io_prep_work_files(req
);
5994 * Queued up for async execution, worker will release
5995 * submit reference when the iocb is actually submitted.
5997 io_queue_async_work(req
);
6001 io_queue_linked_timeout(linked_timeout
);
6005 if (unlikely(ret
)) {
6007 /* un-prep timeout, so it'll be killed as any other linked */
6008 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6009 req_set_fail_links(req
);
6011 io_req_complete(req
, ret
);
6015 /* drop submission reference */
6016 nxt
= io_put_req_find_next(req
);
6018 io_queue_linked_timeout(linked_timeout
);
6023 if (req
->flags
& REQ_F_FORCE_ASYNC
)
6029 revert_creds(old_creds
);
6032 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6033 struct io_comp_state
*cs
)
6037 ret
= io_req_defer(req
, sqe
);
6039 if (ret
!= -EIOCBQUEUED
) {
6041 req_set_fail_links(req
);
6043 io_req_complete(req
, ret
);
6045 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6047 ret
= io_req_defer_prep(req
, sqe
);
6053 * Never try inline submit of IOSQE_ASYNC is set, go straight
6054 * to async execution.
6056 io_req_init_async(req
);
6057 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
6058 io_queue_async_work(req
);
6060 __io_queue_sqe(req
, sqe
, cs
);
6064 static inline void io_queue_link_head(struct io_kiocb
*req
,
6065 struct io_comp_state
*cs
)
6067 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6069 io_req_complete(req
, -ECANCELED
);
6071 io_queue_sqe(req
, NULL
, cs
);
6074 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6075 struct io_kiocb
**link
, struct io_comp_state
*cs
)
6077 struct io_ring_ctx
*ctx
= req
->ctx
;
6081 * If we already have a head request, queue this one for async
6082 * submittal once the head completes. If we don't have a head but
6083 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6084 * submitted sync once the chain is complete. If none of those
6085 * conditions are true (normal request), then just queue it.
6088 struct io_kiocb
*head
= *link
;
6091 * Taking sequential execution of a link, draining both sides
6092 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6093 * requests in the link. So, it drains the head and the
6094 * next after the link request. The last one is done via
6095 * drain_next flag to persist the effect across calls.
6097 if (req
->flags
& REQ_F_IO_DRAIN
) {
6098 head
->flags
|= REQ_F_IO_DRAIN
;
6099 ctx
->drain_next
= 1;
6101 ret
= io_req_defer_prep(req
, sqe
);
6102 if (unlikely(ret
)) {
6103 /* fail even hard links since we don't submit */
6104 head
->flags
|= REQ_F_FAIL_LINK
;
6107 trace_io_uring_link(ctx
, req
, head
);
6108 io_get_req_task(req
);
6109 list_add_tail(&req
->link_list
, &head
->link_list
);
6111 /* last request of a link, enqueue the link */
6112 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6113 io_queue_link_head(head
, cs
);
6117 if (unlikely(ctx
->drain_next
)) {
6118 req
->flags
|= REQ_F_IO_DRAIN
;
6119 ctx
->drain_next
= 0;
6121 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6122 req
->flags
|= REQ_F_LINK_HEAD
;
6123 INIT_LIST_HEAD(&req
->link_list
);
6125 ret
= io_req_defer_prep(req
, sqe
);
6127 req
->flags
|= REQ_F_FAIL_LINK
;
6130 io_queue_sqe(req
, sqe
, cs
);
6138 * Batched submission is done, ensure local IO is flushed out.
6140 static void io_submit_state_end(struct io_submit_state
*state
)
6142 if (!list_empty(&state
->comp
.list
))
6143 io_submit_flush_completions(&state
->comp
);
6144 blk_finish_plug(&state
->plug
);
6145 io_state_file_put(state
);
6146 if (state
->free_reqs
)
6147 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
6151 * Start submission side cache.
6153 static void io_submit_state_start(struct io_submit_state
*state
,
6154 struct io_ring_ctx
*ctx
, unsigned int max_ios
)
6156 blk_start_plug(&state
->plug
);
6158 state
->plug
.nowait
= true;
6161 INIT_LIST_HEAD(&state
->comp
.list
);
6162 state
->comp
.ctx
= ctx
;
6163 state
->free_reqs
= 0;
6165 state
->ios_left
= max_ios
;
6168 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6170 struct io_rings
*rings
= ctx
->rings
;
6173 * Ensure any loads from the SQEs are done at this point,
6174 * since once we write the new head, the application could
6175 * write new data to them.
6177 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6181 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6182 * that is mapped by userspace. This means that care needs to be taken to
6183 * ensure that reads are stable, as we cannot rely on userspace always
6184 * being a good citizen. If members of the sqe are validated and then later
6185 * used, it's important that those reads are done through READ_ONCE() to
6186 * prevent a re-load down the line.
6188 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6190 u32
*sq_array
= ctx
->sq_array
;
6194 * The cached sq head (or cq tail) serves two purposes:
6196 * 1) allows us to batch the cost of updating the user visible
6198 * 2) allows the kernel side to track the head on its own, even
6199 * though the application is the one updating it.
6201 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
6202 if (likely(head
< ctx
->sq_entries
))
6203 return &ctx
->sq_sqes
[head
];
6205 /* drop invalid entries */
6206 ctx
->cached_sq_dropped
++;
6207 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6211 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
6213 ctx
->cached_sq_head
++;
6216 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6217 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6218 IOSQE_BUFFER_SELECT)
6220 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6221 const struct io_uring_sqe
*sqe
,
6222 struct io_submit_state
*state
)
6224 unsigned int sqe_flags
;
6227 req
->opcode
= READ_ONCE(sqe
->opcode
);
6228 req
->user_data
= READ_ONCE(sqe
->user_data
);
6233 /* one is dropped after submission, the other at completion */
6234 refcount_set(&req
->refs
, 2);
6235 req
->task
= current
;
6238 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6241 if (unlikely(io_sq_thread_acquire_mm(ctx
, req
)))
6244 sqe_flags
= READ_ONCE(sqe
->flags
);
6245 /* enforce forwards compatibility on users */
6246 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6249 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6250 !io_op_defs
[req
->opcode
].buffer_select
)
6253 id
= READ_ONCE(sqe
->personality
);
6255 io_req_init_async(req
);
6256 req
->work
.creds
= idr_find(&ctx
->personality_idr
, id
);
6257 if (unlikely(!req
->work
.creds
))
6259 get_cred(req
->work
.creds
);
6262 /* same numerical values with corresponding REQ_F_*, safe to copy */
6263 req
->flags
|= sqe_flags
;
6265 if (!io_op_defs
[req
->opcode
].needs_file
)
6268 return io_req_set_file(state
, req
, READ_ONCE(sqe
->fd
));
6271 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
,
6272 struct file
*ring_file
, int ring_fd
)
6274 struct io_submit_state state
;
6275 struct io_kiocb
*link
= NULL
;
6276 int i
, submitted
= 0;
6278 /* if we have a backlog and couldn't flush it all, return BUSY */
6279 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6280 if (!list_empty(&ctx
->cq_overflow_list
) &&
6281 !io_cqring_overflow_flush(ctx
, false))
6285 /* make sure SQ entry isn't read before tail */
6286 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6288 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6291 io_submit_state_start(&state
, ctx
, nr
);
6293 ctx
->ring_fd
= ring_fd
;
6294 ctx
->ring_file
= ring_file
;
6296 for (i
= 0; i
< nr
; i
++) {
6297 const struct io_uring_sqe
*sqe
;
6298 struct io_kiocb
*req
;
6301 sqe
= io_get_sqe(ctx
);
6302 if (unlikely(!sqe
)) {
6303 io_consume_sqe(ctx
);
6306 req
= io_alloc_req(ctx
, &state
);
6307 if (unlikely(!req
)) {
6309 submitted
= -EAGAIN
;
6313 err
= io_init_req(ctx
, req
, sqe
, &state
);
6314 io_consume_sqe(ctx
);
6315 /* will complete beyond this point, count as submitted */
6318 if (unlikely(err
)) {
6321 io_req_complete(req
, err
);
6325 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6326 true, io_async_submit(ctx
));
6327 err
= io_submit_sqe(req
, sqe
, &link
, &state
.comp
);
6332 if (unlikely(submitted
!= nr
)) {
6333 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6335 percpu_ref_put_many(&ctx
->refs
, nr
- ref_used
);
6338 io_queue_link_head(link
, &state
.comp
);
6339 io_submit_state_end(&state
);
6341 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6342 io_commit_sqring(ctx
);
6347 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6349 /* Tell userspace we may need a wakeup call */
6350 spin_lock_irq(&ctx
->completion_lock
);
6351 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6352 spin_unlock_irq(&ctx
->completion_lock
);
6355 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6357 spin_lock_irq(&ctx
->completion_lock
);
6358 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6359 spin_unlock_irq(&ctx
->completion_lock
);
6362 static int io_sq_thread(void *data
)
6364 struct io_ring_ctx
*ctx
= data
;
6365 const struct cred
*old_cred
;
6367 unsigned long timeout
;
6370 complete(&ctx
->sq_thread_comp
);
6372 old_cred
= override_creds(ctx
->creds
);
6374 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6375 while (!kthread_should_park()) {
6376 unsigned int to_submit
;
6378 if (!list_empty(&ctx
->iopoll_list
)) {
6379 unsigned nr_events
= 0;
6381 mutex_lock(&ctx
->uring_lock
);
6382 if (!list_empty(&ctx
->iopoll_list
) && !need_resched())
6383 io_do_iopoll(ctx
, &nr_events
, 0);
6385 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6386 mutex_unlock(&ctx
->uring_lock
);
6389 to_submit
= io_sqring_entries(ctx
);
6392 * If submit got -EBUSY, flag us as needing the application
6393 * to enter the kernel to reap and flush events.
6395 if (!to_submit
|| ret
== -EBUSY
|| need_resched()) {
6397 * Drop cur_mm before scheduling, we can't hold it for
6398 * long periods (or over schedule()). Do this before
6399 * adding ourselves to the waitqueue, as the unuse/drop
6402 io_sq_thread_drop_mm();
6405 * We're polling. If we're within the defined idle
6406 * period, then let us spin without work before going
6407 * to sleep. The exception is if we got EBUSY doing
6408 * more IO, we should wait for the application to
6409 * reap events and wake us up.
6411 if (!list_empty(&ctx
->iopoll_list
) || need_resched() ||
6412 (!time_after(jiffies
, timeout
) && ret
!= -EBUSY
&&
6413 !percpu_ref_is_dying(&ctx
->refs
))) {
6419 prepare_to_wait(&ctx
->sqo_wait
, &wait
,
6420 TASK_INTERRUPTIBLE
);
6423 * While doing polled IO, before going to sleep, we need
6424 * to check if there are new reqs added to iopoll_list,
6425 * it is because reqs may have been punted to io worker
6426 * and will be added to iopoll_list later, hence check
6427 * the iopoll_list again.
6429 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6430 !list_empty_careful(&ctx
->iopoll_list
)) {
6431 finish_wait(&ctx
->sqo_wait
, &wait
);
6435 io_ring_set_wakeup_flag(ctx
);
6437 to_submit
= io_sqring_entries(ctx
);
6438 if (!to_submit
|| ret
== -EBUSY
) {
6439 if (kthread_should_park()) {
6440 finish_wait(&ctx
->sqo_wait
, &wait
);
6443 if (io_run_task_work()) {
6444 finish_wait(&ctx
->sqo_wait
, &wait
);
6445 io_ring_clear_wakeup_flag(ctx
);
6448 if (signal_pending(current
))
6449 flush_signals(current
);
6451 finish_wait(&ctx
->sqo_wait
, &wait
);
6453 io_ring_clear_wakeup_flag(ctx
);
6457 finish_wait(&ctx
->sqo_wait
, &wait
);
6459 io_ring_clear_wakeup_flag(ctx
);
6462 mutex_lock(&ctx
->uring_lock
);
6463 if (likely(!percpu_ref_is_dying(&ctx
->refs
)))
6464 ret
= io_submit_sqes(ctx
, to_submit
, NULL
, -1);
6465 mutex_unlock(&ctx
->uring_lock
);
6466 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6471 io_sq_thread_drop_mm();
6472 revert_creds(old_cred
);
6479 struct io_wait_queue
{
6480 struct wait_queue_entry wq
;
6481 struct io_ring_ctx
*ctx
;
6483 unsigned nr_timeouts
;
6486 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
6488 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6491 * Wake up if we have enough events, or if a timeout occurred since we
6492 * started waiting. For timeouts, we always want to return to userspace,
6493 * regardless of event count.
6495 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
6496 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6499 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6500 int wake_flags
, void *key
)
6502 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6505 /* use noflush == true, as we can't safely rely on locking context */
6506 if (!io_should_wake(iowq
, true))
6509 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6513 * Wait until events become available, if we don't already have some. The
6514 * application must reap them itself, as they reside on the shared cq ring.
6516 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6517 const sigset_t __user
*sig
, size_t sigsz
)
6519 struct io_wait_queue iowq
= {
6522 .func
= io_wake_function
,
6523 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6526 .to_wait
= min_events
,
6528 struct io_rings
*rings
= ctx
->rings
;
6532 if (io_cqring_events(ctx
, false) >= min_events
)
6534 if (!io_run_task_work())
6539 #ifdef CONFIG_COMPAT
6540 if (in_compat_syscall())
6541 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6545 ret
= set_user_sigmask(sig
, sigsz
);
6551 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6552 trace_io_uring_cqring_wait(ctx
, min_events
);
6554 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
6555 TASK_INTERRUPTIBLE
);
6556 /* make sure we run task_work before checking for signals */
6557 if (io_run_task_work())
6559 if (signal_pending(current
)) {
6560 if (current
->jobctl
& JOBCTL_TASK_WORK
) {
6561 spin_lock_irq(¤t
->sighand
->siglock
);
6562 current
->jobctl
&= ~JOBCTL_TASK_WORK
;
6563 recalc_sigpending();
6564 spin_unlock_irq(¤t
->sighand
->siglock
);
6570 if (io_should_wake(&iowq
, false))
6574 finish_wait(&ctx
->wait
, &iowq
.wq
);
6576 restore_saved_sigmask_unless(ret
== -EINTR
);
6578 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
6581 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6583 #if defined(CONFIG_UNIX)
6584 if (ctx
->ring_sock
) {
6585 struct sock
*sock
= ctx
->ring_sock
->sk
;
6586 struct sk_buff
*skb
;
6588 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
6594 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6597 file
= io_file_from_index(ctx
, i
);
6604 static void io_file_ref_kill(struct percpu_ref
*ref
)
6606 struct fixed_file_data
*data
;
6608 data
= container_of(ref
, struct fixed_file_data
, refs
);
6609 complete(&data
->done
);
6612 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6614 struct fixed_file_data
*data
= ctx
->file_data
;
6615 struct fixed_file_ref_node
*ref_node
= NULL
;
6616 unsigned nr_tables
, i
;
6621 spin_lock(&data
->lock
);
6622 if (!list_empty(&data
->ref_list
))
6623 ref_node
= list_first_entry(&data
->ref_list
,
6624 struct fixed_file_ref_node
, node
);
6625 spin_unlock(&data
->lock
);
6627 percpu_ref_kill(&ref_node
->refs
);
6629 percpu_ref_kill(&data
->refs
);
6631 /* wait for all refs nodes to complete */
6632 flush_delayed_work(&ctx
->file_put_work
);
6633 wait_for_completion(&data
->done
);
6635 __io_sqe_files_unregister(ctx
);
6636 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
6637 for (i
= 0; i
< nr_tables
; i
++)
6638 kfree(data
->table
[i
].files
);
6640 percpu_ref_exit(&data
->refs
);
6642 ctx
->file_data
= NULL
;
6643 ctx
->nr_user_files
= 0;
6647 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
6649 if (ctx
->sqo_thread
) {
6650 wait_for_completion(&ctx
->sq_thread_comp
);
6652 * The park is a bit of a work-around, without it we get
6653 * warning spews on shutdown with SQPOLL set and affinity
6654 * set to a single CPU.
6656 kthread_park(ctx
->sqo_thread
);
6657 kthread_stop(ctx
->sqo_thread
);
6658 ctx
->sqo_thread
= NULL
;
6662 static void io_finish_async(struct io_ring_ctx
*ctx
)
6664 io_sq_thread_stop(ctx
);
6667 io_wq_destroy(ctx
->io_wq
);
6672 #if defined(CONFIG_UNIX)
6674 * Ensure the UNIX gc is aware of our file set, so we are certain that
6675 * the io_uring can be safely unregistered on process exit, even if we have
6676 * loops in the file referencing.
6678 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
6680 struct sock
*sk
= ctx
->ring_sock
->sk
;
6681 struct scm_fp_list
*fpl
;
6682 struct sk_buff
*skb
;
6685 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
6689 skb
= alloc_skb(0, GFP_KERNEL
);
6698 fpl
->user
= get_uid(ctx
->user
);
6699 for (i
= 0; i
< nr
; i
++) {
6700 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
6704 fpl
->fp
[nr_files
] = get_file(file
);
6705 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
6710 fpl
->max
= SCM_MAX_FD
;
6711 fpl
->count
= nr_files
;
6712 UNIXCB(skb
).fp
= fpl
;
6713 skb
->destructor
= unix_destruct_scm
;
6714 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
6715 skb_queue_head(&sk
->sk_receive_queue
, skb
);
6717 for (i
= 0; i
< nr_files
; i
++)
6728 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
6729 * causes regular reference counting to break down. We rely on the UNIX
6730 * garbage collection to take care of this problem for us.
6732 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6734 unsigned left
, total
;
6738 left
= ctx
->nr_user_files
;
6740 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
6742 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
6746 total
+= this_files
;
6752 while (total
< ctx
->nr_user_files
) {
6753 struct file
*file
= io_file_from_index(ctx
, total
);
6763 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6769 static int io_sqe_alloc_file_tables(struct io_ring_ctx
*ctx
, unsigned nr_tables
,
6774 for (i
= 0; i
< nr_tables
; i
++) {
6775 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6776 unsigned this_files
;
6778 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
6779 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
6783 nr_files
-= this_files
;
6789 for (i
= 0; i
< nr_tables
; i
++) {
6790 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6791 kfree(table
->files
);
6796 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
6798 #if defined(CONFIG_UNIX)
6799 struct sock
*sock
= ctx
->ring_sock
->sk
;
6800 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
6801 struct sk_buff
*skb
;
6804 __skb_queue_head_init(&list
);
6807 * Find the skb that holds this file in its SCM_RIGHTS. When found,
6808 * remove this entry and rearrange the file array.
6810 skb
= skb_dequeue(head
);
6812 struct scm_fp_list
*fp
;
6814 fp
= UNIXCB(skb
).fp
;
6815 for (i
= 0; i
< fp
->count
; i
++) {
6818 if (fp
->fp
[i
] != file
)
6821 unix_notinflight(fp
->user
, fp
->fp
[i
]);
6822 left
= fp
->count
- 1 - i
;
6824 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
6825 left
* sizeof(struct file
*));
6832 __skb_queue_tail(&list
, skb
);
6842 __skb_queue_tail(&list
, skb
);
6844 skb
= skb_dequeue(head
);
6847 if (skb_peek(&list
)) {
6848 spin_lock_irq(&head
->lock
);
6849 while ((skb
= __skb_dequeue(&list
)) != NULL
)
6850 __skb_queue_tail(head
, skb
);
6851 spin_unlock_irq(&head
->lock
);
6858 struct io_file_put
{
6859 struct list_head list
;
6863 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
6865 struct fixed_file_data
*file_data
= ref_node
->file_data
;
6866 struct io_ring_ctx
*ctx
= file_data
->ctx
;
6867 struct io_file_put
*pfile
, *tmp
;
6869 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
6870 list_del(&pfile
->list
);
6871 io_ring_file_put(ctx
, pfile
->file
);
6875 spin_lock(&file_data
->lock
);
6876 list_del(&ref_node
->node
);
6877 spin_unlock(&file_data
->lock
);
6879 percpu_ref_exit(&ref_node
->refs
);
6881 percpu_ref_put(&file_data
->refs
);
6884 static void io_file_put_work(struct work_struct
*work
)
6886 struct io_ring_ctx
*ctx
;
6887 struct llist_node
*node
;
6889 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
6890 node
= llist_del_all(&ctx
->file_put_llist
);
6893 struct fixed_file_ref_node
*ref_node
;
6894 struct llist_node
*next
= node
->next
;
6896 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
6897 __io_file_put_work(ref_node
);
6902 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
6904 struct fixed_file_ref_node
*ref_node
;
6905 struct io_ring_ctx
*ctx
;
6909 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
6910 ctx
= ref_node
->file_data
->ctx
;
6912 if (percpu_ref_is_dying(&ctx
->file_data
->refs
))
6915 first_add
= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
6917 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
6919 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
6922 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
6923 struct io_ring_ctx
*ctx
)
6925 struct fixed_file_ref_node
*ref_node
;
6927 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
6929 return ERR_PTR(-ENOMEM
);
6931 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
6934 return ERR_PTR(-ENOMEM
);
6936 INIT_LIST_HEAD(&ref_node
->node
);
6937 INIT_LIST_HEAD(&ref_node
->file_list
);
6938 ref_node
->file_data
= ctx
->file_data
;
6942 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
6944 percpu_ref_exit(&ref_node
->refs
);
6948 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
6951 __s32 __user
*fds
= (__s32 __user
*) arg
;
6956 struct fixed_file_ref_node
*ref_node
;
6962 if (nr_args
> IORING_MAX_FIXED_FILES
)
6965 ctx
->file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
6966 if (!ctx
->file_data
)
6968 ctx
->file_data
->ctx
= ctx
;
6969 init_completion(&ctx
->file_data
->done
);
6970 INIT_LIST_HEAD(&ctx
->file_data
->ref_list
);
6971 spin_lock_init(&ctx
->file_data
->lock
);
6973 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
6974 ctx
->file_data
->table
= kcalloc(nr_tables
,
6975 sizeof(struct fixed_file_table
),
6977 if (!ctx
->file_data
->table
) {
6978 kfree(ctx
->file_data
);
6979 ctx
->file_data
= NULL
;
6983 if (percpu_ref_init(&ctx
->file_data
->refs
, io_file_ref_kill
,
6984 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
)) {
6985 kfree(ctx
->file_data
->table
);
6986 kfree(ctx
->file_data
);
6987 ctx
->file_data
= NULL
;
6991 if (io_sqe_alloc_file_tables(ctx
, nr_tables
, nr_args
)) {
6992 percpu_ref_exit(&ctx
->file_data
->refs
);
6993 kfree(ctx
->file_data
->table
);
6994 kfree(ctx
->file_data
);
6995 ctx
->file_data
= NULL
;
6999 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7000 struct fixed_file_table
*table
;
7004 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
)))
7006 /* allow sparse sets */
7012 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7013 index
= i
& IORING_FILE_TABLE_MASK
;
7021 * Don't allow io_uring instances to be registered. If UNIX
7022 * isn't enabled, then this causes a reference cycle and this
7023 * instance can never get freed. If UNIX is enabled we'll
7024 * handle it just fine, but there's still no point in allowing
7025 * a ring fd as it doesn't support regular read/write anyway.
7027 if (file
->f_op
== &io_uring_fops
) {
7032 table
->files
[index
] = file
;
7036 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7037 file
= io_file_from_index(ctx
, i
);
7041 for (i
= 0; i
< nr_tables
; i
++)
7042 kfree(ctx
->file_data
->table
[i
].files
);
7044 percpu_ref_exit(&ctx
->file_data
->refs
);
7045 kfree(ctx
->file_data
->table
);
7046 kfree(ctx
->file_data
);
7047 ctx
->file_data
= NULL
;
7048 ctx
->nr_user_files
= 0;
7052 ret
= io_sqe_files_scm(ctx
);
7054 io_sqe_files_unregister(ctx
);
7058 ref_node
= alloc_fixed_file_ref_node(ctx
);
7059 if (IS_ERR(ref_node
)) {
7060 io_sqe_files_unregister(ctx
);
7061 return PTR_ERR(ref_node
);
7064 ctx
->file_data
->cur_refs
= &ref_node
->refs
;
7065 spin_lock(&ctx
->file_data
->lock
);
7066 list_add(&ref_node
->node
, &ctx
->file_data
->ref_list
);
7067 spin_unlock(&ctx
->file_data
->lock
);
7068 percpu_ref_get(&ctx
->file_data
->refs
);
7072 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7075 #if defined(CONFIG_UNIX)
7076 struct sock
*sock
= ctx
->ring_sock
->sk
;
7077 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7078 struct sk_buff
*skb
;
7081 * See if we can merge this file into an existing skb SCM_RIGHTS
7082 * file set. If there's no room, fall back to allocating a new skb
7083 * and filling it in.
7085 spin_lock_irq(&head
->lock
);
7086 skb
= skb_peek(head
);
7088 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7090 if (fpl
->count
< SCM_MAX_FD
) {
7091 __skb_unlink(skb
, head
);
7092 spin_unlock_irq(&head
->lock
);
7093 fpl
->fp
[fpl
->count
] = get_file(file
);
7094 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7096 spin_lock_irq(&head
->lock
);
7097 __skb_queue_head(head
, skb
);
7102 spin_unlock_irq(&head
->lock
);
7109 return __io_sqe_files_scm(ctx
, 1, index
);
7115 static int io_queue_file_removal(struct fixed_file_data
*data
,
7118 struct io_file_put
*pfile
;
7119 struct percpu_ref
*refs
= data
->cur_refs
;
7120 struct fixed_file_ref_node
*ref_node
;
7122 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
7126 ref_node
= container_of(refs
, struct fixed_file_ref_node
, refs
);
7128 list_add(&pfile
->list
, &ref_node
->file_list
);
7133 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7134 struct io_uring_files_update
*up
,
7137 struct fixed_file_data
*data
= ctx
->file_data
;
7138 struct fixed_file_ref_node
*ref_node
;
7143 bool needs_switch
= false;
7145 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7147 if (done
> ctx
->nr_user_files
)
7150 ref_node
= alloc_fixed_file_ref_node(ctx
);
7151 if (IS_ERR(ref_node
))
7152 return PTR_ERR(ref_node
);
7155 fds
= u64_to_user_ptr(up
->fds
);
7157 struct fixed_file_table
*table
;
7161 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7165 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
7166 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7167 index
= i
& IORING_FILE_TABLE_MASK
;
7168 if (table
->files
[index
]) {
7169 file
= io_file_from_index(ctx
, index
);
7170 err
= io_queue_file_removal(data
, file
);
7173 table
->files
[index
] = NULL
;
7174 needs_switch
= true;
7183 * Don't allow io_uring instances to be registered. If
7184 * UNIX isn't enabled, then this causes a reference
7185 * cycle and this instance can never get freed. If UNIX
7186 * is enabled we'll handle it just fine, but there's
7187 * still no point in allowing a ring fd as it doesn't
7188 * support regular read/write anyway.
7190 if (file
->f_op
== &io_uring_fops
) {
7195 table
->files
[index
] = file
;
7196 err
= io_sqe_file_register(ctx
, file
, i
);
7208 percpu_ref_kill(data
->cur_refs
);
7209 spin_lock(&data
->lock
);
7210 list_add(&ref_node
->node
, &data
->ref_list
);
7211 data
->cur_refs
= &ref_node
->refs
;
7212 spin_unlock(&data
->lock
);
7213 percpu_ref_get(&ctx
->file_data
->refs
);
7215 destroy_fixed_file_ref_node(ref_node
);
7217 return done
? done
: err
;
7220 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7223 struct io_uring_files_update up
;
7225 if (!ctx
->file_data
)
7229 if (copy_from_user(&up
, arg
, sizeof(up
)))
7234 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7237 static void io_free_work(struct io_wq_work
*work
)
7239 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7241 /* Consider that io_steal_work() relies on this ref */
7245 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
7246 struct io_uring_params
*p
)
7248 struct io_wq_data data
;
7250 struct io_ring_ctx
*ctx_attach
;
7251 unsigned int concurrency
;
7254 data
.user
= ctx
->user
;
7255 data
.free_work
= io_free_work
;
7256 data
.do_work
= io_wq_submit_work
;
7258 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
7259 /* Do QD, or 4 * CPUS, whatever is smallest */
7260 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7262 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
7263 if (IS_ERR(ctx
->io_wq
)) {
7264 ret
= PTR_ERR(ctx
->io_wq
);
7270 f
= fdget(p
->wq_fd
);
7274 if (f
.file
->f_op
!= &io_uring_fops
) {
7279 ctx_attach
= f
.file
->private_data
;
7280 /* @io_wq is protected by holding the fd */
7281 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
7286 ctx
->io_wq
= ctx_attach
->io_wq
;
7292 static int io_sq_offload_start(struct io_ring_ctx
*ctx
,
7293 struct io_uring_params
*p
)
7297 mmgrab(current
->mm
);
7298 ctx
->sqo_mm
= current
->mm
;
7300 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7302 if (!capable(CAP_SYS_ADMIN
))
7305 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
7306 if (!ctx
->sq_thread_idle
)
7307 ctx
->sq_thread_idle
= HZ
;
7309 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7310 int cpu
= p
->sq_thread_cpu
;
7313 if (cpu
>= nr_cpu_ids
)
7315 if (!cpu_online(cpu
))
7318 ctx
->sqo_thread
= kthread_create_on_cpu(io_sq_thread
,
7322 ctx
->sqo_thread
= kthread_create(io_sq_thread
, ctx
,
7325 if (IS_ERR(ctx
->sqo_thread
)) {
7326 ret
= PTR_ERR(ctx
->sqo_thread
);
7327 ctx
->sqo_thread
= NULL
;
7330 wake_up_process(ctx
->sqo_thread
);
7331 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7332 /* Can't have SQ_AFF without SQPOLL */
7337 ret
= io_init_wq_offload(ctx
, p
);
7343 io_finish_async(ctx
);
7345 mmdrop(ctx
->sqo_mm
);
7351 static inline void __io_unaccount_mem(struct user_struct
*user
,
7352 unsigned long nr_pages
)
7354 atomic_long_sub(nr_pages
, &user
->locked_vm
);
7357 static inline int __io_account_mem(struct user_struct
*user
,
7358 unsigned long nr_pages
)
7360 unsigned long page_limit
, cur_pages
, new_pages
;
7362 /* Don't allow more pages than we can safely lock */
7363 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
7366 cur_pages
= atomic_long_read(&user
->locked_vm
);
7367 new_pages
= cur_pages
+ nr_pages
;
7368 if (new_pages
> page_limit
)
7370 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
7371 new_pages
) != cur_pages
);
7376 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7377 enum io_mem_account acct
)
7380 __io_unaccount_mem(ctx
->user
, nr_pages
);
7383 if (acct
== ACCT_LOCKED
)
7384 ctx
->sqo_mm
->locked_vm
-= nr_pages
;
7385 else if (acct
== ACCT_PINNED
)
7386 atomic64_sub(nr_pages
, &ctx
->sqo_mm
->pinned_vm
);
7390 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7391 enum io_mem_account acct
)
7395 if (ctx
->limit_mem
) {
7396 ret
= __io_account_mem(ctx
->user
, nr_pages
);
7402 if (acct
== ACCT_LOCKED
)
7403 ctx
->sqo_mm
->locked_vm
+= nr_pages
;
7404 else if (acct
== ACCT_PINNED
)
7405 atomic64_add(nr_pages
, &ctx
->sqo_mm
->pinned_vm
);
7411 static void io_mem_free(void *ptr
)
7418 page
= virt_to_head_page(ptr
);
7419 if (put_page_testzero(page
))
7420 free_compound_page(page
);
7423 static void *io_mem_alloc(size_t size
)
7425 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
7428 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
7431 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
7434 struct io_rings
*rings
;
7435 size_t off
, sq_array_size
;
7437 off
= struct_size(rings
, cqes
, cq_entries
);
7438 if (off
== SIZE_MAX
)
7442 off
= ALIGN(off
, SMP_CACHE_BYTES
);
7450 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
7451 if (sq_array_size
== SIZE_MAX
)
7454 if (check_add_overflow(off
, sq_array_size
, &off
))
7460 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
7464 pages
= (size_t)1 << get_order(
7465 rings_size(sq_entries
, cq_entries
, NULL
));
7466 pages
+= (size_t)1 << get_order(
7467 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
7472 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
7476 if (!ctx
->user_bufs
)
7479 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7480 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7482 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
7483 unpin_user_page(imu
->bvec
[j
].bv_page
);
7485 io_unaccount_mem(ctx
, imu
->nr_bvecs
, ACCT_PINNED
);
7490 kfree(ctx
->user_bufs
);
7491 ctx
->user_bufs
= NULL
;
7492 ctx
->nr_user_bufs
= 0;
7496 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
7497 void __user
*arg
, unsigned index
)
7499 struct iovec __user
*src
;
7501 #ifdef CONFIG_COMPAT
7503 struct compat_iovec __user
*ciovs
;
7504 struct compat_iovec ciov
;
7506 ciovs
= (struct compat_iovec __user
*) arg
;
7507 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
7510 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
7511 dst
->iov_len
= ciov
.iov_len
;
7515 src
= (struct iovec __user
*) arg
;
7516 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
7521 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7524 struct vm_area_struct
**vmas
= NULL
;
7525 struct page
**pages
= NULL
;
7526 int i
, j
, got_pages
= 0;
7531 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
7534 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
7536 if (!ctx
->user_bufs
)
7539 for (i
= 0; i
< nr_args
; i
++) {
7540 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7541 unsigned long off
, start
, end
, ubuf
;
7546 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
7551 * Don't impose further limits on the size and buffer
7552 * constraints here, we'll -EINVAL later when IO is
7553 * submitted if they are wrong.
7556 if (!iov
.iov_base
|| !iov
.iov_len
)
7559 /* arbitrary limit, but we need something */
7560 if (iov
.iov_len
> SZ_1G
)
7563 ubuf
= (unsigned long) iov
.iov_base
;
7564 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
7565 start
= ubuf
>> PAGE_SHIFT
;
7566 nr_pages
= end
- start
;
7568 ret
= io_account_mem(ctx
, nr_pages
, ACCT_PINNED
);
7573 if (!pages
|| nr_pages
> got_pages
) {
7576 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
7578 vmas
= kvmalloc_array(nr_pages
,
7579 sizeof(struct vm_area_struct
*),
7581 if (!pages
|| !vmas
) {
7583 io_unaccount_mem(ctx
, nr_pages
, ACCT_PINNED
);
7586 got_pages
= nr_pages
;
7589 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
7593 io_unaccount_mem(ctx
, nr_pages
, ACCT_PINNED
);
7598 mmap_read_lock(current
->mm
);
7599 pret
= pin_user_pages(ubuf
, nr_pages
,
7600 FOLL_WRITE
| FOLL_LONGTERM
,
7602 if (pret
== nr_pages
) {
7603 /* don't support file backed memory */
7604 for (j
= 0; j
< nr_pages
; j
++) {
7605 struct vm_area_struct
*vma
= vmas
[j
];
7608 !is_file_hugepages(vma
->vm_file
)) {
7614 ret
= pret
< 0 ? pret
: -EFAULT
;
7616 mmap_read_unlock(current
->mm
);
7619 * if we did partial map, or found file backed vmas,
7620 * release any pages we did get
7623 unpin_user_pages(pages
, pret
);
7624 io_unaccount_mem(ctx
, nr_pages
, ACCT_PINNED
);
7629 off
= ubuf
& ~PAGE_MASK
;
7631 for (j
= 0; j
< nr_pages
; j
++) {
7634 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
7635 imu
->bvec
[j
].bv_page
= pages
[j
];
7636 imu
->bvec
[j
].bv_len
= vec_len
;
7637 imu
->bvec
[j
].bv_offset
= off
;
7641 /* store original address for later verification */
7643 imu
->len
= iov
.iov_len
;
7644 imu
->nr_bvecs
= nr_pages
;
7646 ctx
->nr_user_bufs
++;
7654 io_sqe_buffer_unregister(ctx
);
7658 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
7660 __s32 __user
*fds
= arg
;
7666 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
7669 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
7670 if (IS_ERR(ctx
->cq_ev_fd
)) {
7671 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
7672 ctx
->cq_ev_fd
= NULL
;
7679 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
7681 if (ctx
->cq_ev_fd
) {
7682 eventfd_ctx_put(ctx
->cq_ev_fd
);
7683 ctx
->cq_ev_fd
= NULL
;
7690 static int __io_destroy_buffers(int id
, void *p
, void *data
)
7692 struct io_ring_ctx
*ctx
= data
;
7693 struct io_buffer
*buf
= p
;
7695 __io_remove_buffers(ctx
, buf
, id
, -1U);
7699 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
7701 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
7702 idr_destroy(&ctx
->io_buffer_idr
);
7705 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
7707 io_finish_async(ctx
);
7708 io_sqe_buffer_unregister(ctx
);
7710 mmdrop(ctx
->sqo_mm
);
7714 io_sqe_files_unregister(ctx
);
7715 io_eventfd_unregister(ctx
);
7716 io_destroy_buffers(ctx
);
7717 idr_destroy(&ctx
->personality_idr
);
7719 #if defined(CONFIG_UNIX)
7720 if (ctx
->ring_sock
) {
7721 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
7722 sock_release(ctx
->ring_sock
);
7726 io_mem_free(ctx
->rings
);
7727 io_mem_free(ctx
->sq_sqes
);
7729 percpu_ref_exit(&ctx
->refs
);
7730 free_uid(ctx
->user
);
7731 put_cred(ctx
->creds
);
7732 kfree(ctx
->cancel_hash
);
7733 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
7737 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
7739 struct io_ring_ctx
*ctx
= file
->private_data
;
7742 poll_wait(file
, &ctx
->cq_wait
, wait
);
7744 * synchronizes with barrier from wq_has_sleeper call in
7748 if (READ_ONCE(ctx
->rings
->sq
.tail
) - ctx
->cached_sq_head
!=
7749 ctx
->rings
->sq_ring_entries
)
7750 mask
|= EPOLLOUT
| EPOLLWRNORM
;
7751 if (io_cqring_events(ctx
, false))
7752 mask
|= EPOLLIN
| EPOLLRDNORM
;
7757 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
7759 struct io_ring_ctx
*ctx
= file
->private_data
;
7761 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
7764 static int io_remove_personalities(int id
, void *p
, void *data
)
7766 struct io_ring_ctx
*ctx
= data
;
7767 const struct cred
*cred
;
7769 cred
= idr_remove(&ctx
->personality_idr
, id
);
7775 static void io_ring_exit_work(struct work_struct
*work
)
7777 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
7781 * If we're doing polled IO and end up having requests being
7782 * submitted async (out-of-line), then completions can come in while
7783 * we're waiting for refs to drop. We need to reap these manually,
7784 * as nobody else will be looking for them.
7788 io_cqring_overflow_flush(ctx
, true);
7789 io_iopoll_try_reap_events(ctx
);
7790 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
7791 io_ring_ctx_free(ctx
);
7794 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
7796 mutex_lock(&ctx
->uring_lock
);
7797 percpu_ref_kill(&ctx
->refs
);
7798 mutex_unlock(&ctx
->uring_lock
);
7800 io_kill_timeouts(ctx
);
7801 io_poll_remove_all(ctx
);
7804 io_wq_cancel_all(ctx
->io_wq
);
7806 /* if we failed setting up the ctx, we might not have any rings */
7808 io_cqring_overflow_flush(ctx
, true);
7809 io_iopoll_try_reap_events(ctx
);
7810 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
7813 * Do this upfront, so we won't have a grace period where the ring
7814 * is closed but resources aren't reaped yet. This can cause
7815 * spurious failure in setting up a new ring.
7817 io_unaccount_mem(ctx
, ring_pages(ctx
->sq_entries
, ctx
->cq_entries
),
7820 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
7821 queue_work(system_wq
, &ctx
->exit_work
);
7824 static int io_uring_release(struct inode
*inode
, struct file
*file
)
7826 struct io_ring_ctx
*ctx
= file
->private_data
;
7828 file
->private_data
= NULL
;
7829 io_ring_ctx_wait_and_kill(ctx
);
7833 static bool io_wq_files_match(struct io_wq_work
*work
, void *data
)
7835 struct files_struct
*files
= data
;
7837 return work
->files
== files
;
7840 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
7841 struct files_struct
*files
)
7843 if (list_empty_careful(&ctx
->inflight_list
))
7846 /* cancel all at once, should be faster than doing it one by one*/
7847 io_wq_cancel_cb(ctx
->io_wq
, io_wq_files_match
, files
, true);
7849 while (!list_empty_careful(&ctx
->inflight_list
)) {
7850 struct io_kiocb
*cancel_req
= NULL
, *req
;
7853 spin_lock_irq(&ctx
->inflight_lock
);
7854 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
7855 if (req
->work
.files
!= files
)
7857 /* req is being completed, ignore */
7858 if (!refcount_inc_not_zero(&req
->refs
))
7864 prepare_to_wait(&ctx
->inflight_wait
, &wait
,
7865 TASK_UNINTERRUPTIBLE
);
7866 spin_unlock_irq(&ctx
->inflight_lock
);
7868 /* We need to keep going until we don't find a matching req */
7872 if (cancel_req
->flags
& REQ_F_OVERFLOW
) {
7873 spin_lock_irq(&ctx
->completion_lock
);
7874 list_del(&cancel_req
->compl.list
);
7875 cancel_req
->flags
&= ~REQ_F_OVERFLOW
;
7877 io_cqring_mark_overflow(ctx
);
7878 WRITE_ONCE(ctx
->rings
->cq_overflow
,
7879 atomic_inc_return(&ctx
->cached_cq_overflow
));
7880 io_commit_cqring(ctx
);
7881 spin_unlock_irq(&ctx
->completion_lock
);
7884 * Put inflight ref and overflow ref. If that's
7885 * all we had, then we're done with this request.
7887 if (refcount_sub_and_test(2, &cancel_req
->refs
)) {
7888 io_free_req(cancel_req
);
7889 finish_wait(&ctx
->inflight_wait
, &wait
);
7893 io_wq_cancel_work(ctx
->io_wq
, &cancel_req
->work
);
7894 io_put_req(cancel_req
);
7898 finish_wait(&ctx
->inflight_wait
, &wait
);
7902 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
7904 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7905 struct task_struct
*task
= data
;
7907 return req
->task
== task
;
7910 static int io_uring_flush(struct file
*file
, void *data
)
7912 struct io_ring_ctx
*ctx
= file
->private_data
;
7914 io_uring_cancel_files(ctx
, data
);
7917 * If the task is going away, cancel work it may have pending
7919 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
))
7920 io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, current
, true);
7925 static void *io_uring_validate_mmap_request(struct file
*file
,
7926 loff_t pgoff
, size_t sz
)
7928 struct io_ring_ctx
*ctx
= file
->private_data
;
7929 loff_t offset
= pgoff
<< PAGE_SHIFT
;
7934 case IORING_OFF_SQ_RING
:
7935 case IORING_OFF_CQ_RING
:
7938 case IORING_OFF_SQES
:
7942 return ERR_PTR(-EINVAL
);
7945 page
= virt_to_head_page(ptr
);
7946 if (sz
> page_size(page
))
7947 return ERR_PTR(-EINVAL
);
7954 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
7956 size_t sz
= vma
->vm_end
- vma
->vm_start
;
7960 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
7962 return PTR_ERR(ptr
);
7964 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
7965 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
7968 #else /* !CONFIG_MMU */
7970 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
7972 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
7975 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
7977 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
7980 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
7981 unsigned long addr
, unsigned long len
,
7982 unsigned long pgoff
, unsigned long flags
)
7986 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
7988 return PTR_ERR(ptr
);
7990 return (unsigned long) ptr
;
7993 #endif /* !CONFIG_MMU */
7995 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
7996 u32
, min_complete
, u32
, flags
, const sigset_t __user
*, sig
,
7999 struct io_ring_ctx
*ctx
;
8006 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
))
8014 if (f
.file
->f_op
!= &io_uring_fops
)
8018 ctx
= f
.file
->private_data
;
8019 if (!percpu_ref_tryget(&ctx
->refs
))
8023 * For SQ polling, the thread will do all submissions and completions.
8024 * Just return the requested submit count, and wake the thread if
8028 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8029 if (!list_empty_careful(&ctx
->cq_overflow_list
))
8030 io_cqring_overflow_flush(ctx
, false);
8031 if (flags
& IORING_ENTER_SQ_WAKEUP
)
8032 wake_up(&ctx
->sqo_wait
);
8033 submitted
= to_submit
;
8034 } else if (to_submit
) {
8035 mutex_lock(&ctx
->uring_lock
);
8036 submitted
= io_submit_sqes(ctx
, to_submit
, f
.file
, fd
);
8037 mutex_unlock(&ctx
->uring_lock
);
8039 if (submitted
!= to_submit
)
8042 if (flags
& IORING_ENTER_GETEVENTS
) {
8043 min_complete
= min(min_complete
, ctx
->cq_entries
);
8046 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
8047 * space applications don't need to do io completion events
8048 * polling again, they can rely on io_sq_thread to do polling
8049 * work, which can reduce cpu usage and uring_lock contention.
8051 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
8052 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8053 ret
= io_iopoll_check(ctx
, min_complete
);
8055 ret
= io_cqring_wait(ctx
, min_complete
, sig
, sigsz
);
8060 percpu_ref_put(&ctx
->refs
);
8063 return submitted
? submitted
: ret
;
8066 #ifdef CONFIG_PROC_FS
8067 static int io_uring_show_cred(int id
, void *p
, void *data
)
8069 const struct cred
*cred
= p
;
8070 struct seq_file
*m
= data
;
8071 struct user_namespace
*uns
= seq_user_ns(m
);
8072 struct group_info
*gi
;
8077 seq_printf(m
, "%5d\n", id
);
8078 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
8079 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
8080 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
8081 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
8082 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
8083 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
8084 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
8085 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
8086 seq_puts(m
, "\n\tGroups:\t");
8087 gi
= cred
->group_info
;
8088 for (g
= 0; g
< gi
->ngroups
; g
++) {
8089 seq_put_decimal_ull(m
, g
? " " : "",
8090 from_kgid_munged(uns
, gi
->gid
[g
]));
8092 seq_puts(m
, "\n\tCapEff:\t");
8093 cap
= cred
->cap_effective
;
8094 CAP_FOR_EACH_U32(__capi
)
8095 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
8100 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
8104 mutex_lock(&ctx
->uring_lock
);
8105 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
8106 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
8107 struct fixed_file_table
*table
;
8110 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
8111 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
8113 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
8115 seq_printf(m
, "%5u: <none>\n", i
);
8117 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
8118 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8119 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
8121 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
8122 (unsigned int) buf
->len
);
8124 if (!idr_is_empty(&ctx
->personality_idr
)) {
8125 seq_printf(m
, "Personalities:\n");
8126 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
8128 seq_printf(m
, "PollList:\n");
8129 spin_lock_irq(&ctx
->completion_lock
);
8130 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
8131 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
8132 struct io_kiocb
*req
;
8134 hlist_for_each_entry(req
, list
, hash_node
)
8135 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
8136 req
->task
->task_works
!= NULL
);
8138 spin_unlock_irq(&ctx
->completion_lock
);
8139 mutex_unlock(&ctx
->uring_lock
);
8142 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
8144 struct io_ring_ctx
*ctx
= f
->private_data
;
8146 if (percpu_ref_tryget(&ctx
->refs
)) {
8147 __io_uring_show_fdinfo(ctx
, m
);
8148 percpu_ref_put(&ctx
->refs
);
8153 static const struct file_operations io_uring_fops
= {
8154 .release
= io_uring_release
,
8155 .flush
= io_uring_flush
,
8156 .mmap
= io_uring_mmap
,
8158 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
8159 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
8161 .poll
= io_uring_poll
,
8162 .fasync
= io_uring_fasync
,
8163 #ifdef CONFIG_PROC_FS
8164 .show_fdinfo
= io_uring_show_fdinfo
,
8168 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
8169 struct io_uring_params
*p
)
8171 struct io_rings
*rings
;
8172 size_t size
, sq_array_offset
;
8174 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
8175 if (size
== SIZE_MAX
)
8178 rings
= io_mem_alloc(size
);
8183 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
8184 rings
->sq_ring_mask
= p
->sq_entries
- 1;
8185 rings
->cq_ring_mask
= p
->cq_entries
- 1;
8186 rings
->sq_ring_entries
= p
->sq_entries
;
8187 rings
->cq_ring_entries
= p
->cq_entries
;
8188 ctx
->sq_mask
= rings
->sq_ring_mask
;
8189 ctx
->cq_mask
= rings
->cq_ring_mask
;
8190 ctx
->sq_entries
= rings
->sq_ring_entries
;
8191 ctx
->cq_entries
= rings
->cq_ring_entries
;
8193 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
8194 if (size
== SIZE_MAX
) {
8195 io_mem_free(ctx
->rings
);
8200 ctx
->sq_sqes
= io_mem_alloc(size
);
8201 if (!ctx
->sq_sqes
) {
8202 io_mem_free(ctx
->rings
);
8211 * Allocate an anonymous fd, this is what constitutes the application
8212 * visible backing of an io_uring instance. The application mmaps this
8213 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
8214 * we have to tie this fd to a socket for file garbage collection purposes.
8216 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
8221 #if defined(CONFIG_UNIX)
8222 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
8228 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
8232 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
8233 O_RDWR
| O_CLOEXEC
);
8236 ret
= PTR_ERR(file
);
8240 #if defined(CONFIG_UNIX)
8241 ctx
->ring_sock
->file
= file
;
8243 fd_install(ret
, file
);
8246 #if defined(CONFIG_UNIX)
8247 sock_release(ctx
->ring_sock
);
8248 ctx
->ring_sock
= NULL
;
8253 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
8254 struct io_uring_params __user
*params
)
8256 struct user_struct
*user
= NULL
;
8257 struct io_ring_ctx
*ctx
;
8263 if (entries
> IORING_MAX_ENTRIES
) {
8264 if (!(p
->flags
& IORING_SETUP_CLAMP
))
8266 entries
= IORING_MAX_ENTRIES
;
8270 * Use twice as many entries for the CQ ring. It's possible for the
8271 * application to drive a higher depth than the size of the SQ ring,
8272 * since the sqes are only used at submission time. This allows for
8273 * some flexibility in overcommitting a bit. If the application has
8274 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
8275 * of CQ ring entries manually.
8277 p
->sq_entries
= roundup_pow_of_two(entries
);
8278 if (p
->flags
& IORING_SETUP_CQSIZE
) {
8280 * If IORING_SETUP_CQSIZE is set, we do the same roundup
8281 * to a power-of-two, if it isn't already. We do NOT impose
8282 * any cq vs sq ring sizing.
8284 if (p
->cq_entries
< p
->sq_entries
)
8286 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
8287 if (!(p
->flags
& IORING_SETUP_CLAMP
))
8289 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
8291 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
8293 p
->cq_entries
= 2 * p
->sq_entries
;
8296 user
= get_uid(current_user());
8297 limit_mem
= !capable(CAP_IPC_LOCK
);
8300 ret
= __io_account_mem(user
,
8301 ring_pages(p
->sq_entries
, p
->cq_entries
));
8308 ctx
= io_ring_ctx_alloc(p
);
8311 __io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
8316 ctx
->compat
= in_compat_syscall();
8318 ctx
->creds
= get_current_cred();
8320 ret
= io_allocate_scq_urings(ctx
, p
);
8324 ret
= io_sq_offload_start(ctx
, p
);
8328 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
8329 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
8330 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
8331 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
8332 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
8333 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
8334 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
8335 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
8337 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
8338 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
8339 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
8340 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
8341 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
8342 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
8343 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
8344 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
8346 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
8347 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
8348 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
8349 IORING_FEAT_POLL_32BITS
;
8351 if (copy_to_user(params
, p
, sizeof(*p
))) {
8357 * Account memory _before_ installing the file descriptor. Once
8358 * the descriptor is installed, it can get closed at any time.
8360 io_account_mem(ctx
, ring_pages(p
->sq_entries
, p
->cq_entries
),
8362 ctx
->limit_mem
= limit_mem
;
8365 * Install ring fd as the very last thing, so we don't risk someone
8366 * having closed it before we finish setup
8368 ret
= io_uring_get_fd(ctx
);
8372 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
8375 io_ring_ctx_wait_and_kill(ctx
);
8380 * Sets up an aio uring context, and returns the fd. Applications asks for a
8381 * ring size, we return the actual sq/cq ring sizes (among other things) in the
8382 * params structure passed in.
8384 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
8386 struct io_uring_params p
;
8389 if (copy_from_user(&p
, params
, sizeof(p
)))
8391 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
8396 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
8397 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
8398 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
))
8401 return io_uring_create(entries
, &p
, params
);
8404 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
8405 struct io_uring_params __user
*, params
)
8407 return io_uring_setup(entries
, params
);
8410 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
8412 struct io_uring_probe
*p
;
8416 size
= struct_size(p
, ops
, nr_args
);
8417 if (size
== SIZE_MAX
)
8419 p
= kzalloc(size
, GFP_KERNEL
);
8424 if (copy_from_user(p
, arg
, size
))
8427 if (memchr_inv(p
, 0, size
))
8430 p
->last_op
= IORING_OP_LAST
- 1;
8431 if (nr_args
> IORING_OP_LAST
)
8432 nr_args
= IORING_OP_LAST
;
8434 for (i
= 0; i
< nr_args
; i
++) {
8436 if (!io_op_defs
[i
].not_supported
)
8437 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
8442 if (copy_to_user(arg
, p
, size
))
8449 static int io_register_personality(struct io_ring_ctx
*ctx
)
8451 const struct cred
*creds
= get_current_cred();
8454 id
= idr_alloc_cyclic(&ctx
->personality_idr
, (void *) creds
, 1,
8455 USHRT_MAX
, GFP_KERNEL
);
8461 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
8463 const struct cred
*old_creds
;
8465 old_creds
= idr_remove(&ctx
->personality_idr
, id
);
8467 put_cred(old_creds
);
8474 static bool io_register_op_must_quiesce(int op
)
8477 case IORING_UNREGISTER_FILES
:
8478 case IORING_REGISTER_FILES_UPDATE
:
8479 case IORING_REGISTER_PROBE
:
8480 case IORING_REGISTER_PERSONALITY
:
8481 case IORING_UNREGISTER_PERSONALITY
:
8488 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
8489 void __user
*arg
, unsigned nr_args
)
8490 __releases(ctx
->uring_lock
)
8491 __acquires(ctx
->uring_lock
)
8496 * We're inside the ring mutex, if the ref is already dying, then
8497 * someone else killed the ctx or is already going through
8498 * io_uring_register().
8500 if (percpu_ref_is_dying(&ctx
->refs
))
8503 if (io_register_op_must_quiesce(opcode
)) {
8504 percpu_ref_kill(&ctx
->refs
);
8507 * Drop uring mutex before waiting for references to exit. If
8508 * another thread is currently inside io_uring_enter() it might
8509 * need to grab the uring_lock to make progress. If we hold it
8510 * here across the drain wait, then we can deadlock. It's safe
8511 * to drop the mutex here, since no new references will come in
8512 * after we've killed the percpu ref.
8514 mutex_unlock(&ctx
->uring_lock
);
8515 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
8516 mutex_lock(&ctx
->uring_lock
);
8518 percpu_ref_resurrect(&ctx
->refs
);
8525 case IORING_REGISTER_BUFFERS
:
8526 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
8528 case IORING_UNREGISTER_BUFFERS
:
8532 ret
= io_sqe_buffer_unregister(ctx
);
8534 case IORING_REGISTER_FILES
:
8535 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
8537 case IORING_UNREGISTER_FILES
:
8541 ret
= io_sqe_files_unregister(ctx
);
8543 case IORING_REGISTER_FILES_UPDATE
:
8544 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
8546 case IORING_REGISTER_EVENTFD
:
8547 case IORING_REGISTER_EVENTFD_ASYNC
:
8551 ret
= io_eventfd_register(ctx
, arg
);
8554 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
8555 ctx
->eventfd_async
= 1;
8557 ctx
->eventfd_async
= 0;
8559 case IORING_UNREGISTER_EVENTFD
:
8563 ret
= io_eventfd_unregister(ctx
);
8565 case IORING_REGISTER_PROBE
:
8567 if (!arg
|| nr_args
> 256)
8569 ret
= io_probe(ctx
, arg
, nr_args
);
8571 case IORING_REGISTER_PERSONALITY
:
8575 ret
= io_register_personality(ctx
);
8577 case IORING_UNREGISTER_PERSONALITY
:
8581 ret
= io_unregister_personality(ctx
, nr_args
);
8588 if (io_register_op_must_quiesce(opcode
)) {
8589 /* bring the ctx back to life */
8590 percpu_ref_reinit(&ctx
->refs
);
8592 reinit_completion(&ctx
->ref_comp
);
8597 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
8598 void __user
*, arg
, unsigned int, nr_args
)
8600 struct io_ring_ctx
*ctx
;
8609 if (f
.file
->f_op
!= &io_uring_fops
)
8612 ctx
= f
.file
->private_data
;
8614 mutex_lock(&ctx
->uring_lock
);
8615 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
8616 mutex_unlock(&ctx
->uring_lock
);
8617 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
8618 ctx
->cq_ev_fd
!= NULL
, ret
);
8624 static int __init
io_uring_init(void)
8626 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
8627 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
8628 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
8631 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
8632 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
8633 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
8634 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
8635 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
8636 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
8637 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
8638 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
8639 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
8640 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
8641 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
8642 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
8643 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
8644 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
8645 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
8646 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
8647 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
8648 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
8649 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
8650 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
8651 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
8652 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
8653 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
8654 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
8655 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
8656 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
8657 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
8658 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
8659 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
8660 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
8661 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
8663 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
8664 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
8665 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
8668 __initcall(io_uring_init
);