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
];
511 const struct iovec
*free_iovec
;
512 struct iov_iter iter
;
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
,
544 REQ_F_BUFFER_SELECTED_BIT
,
545 REQ_F_NO_FILE_TABLE_BIT
,
546 REQ_F_WORK_INITIALIZED_BIT
,
547 REQ_F_TASK_PINNED_BIT
,
549 /* not a real bit, just to check we're not overflowing the space */
555 REQ_F_FIXED_FILE
= BIT(REQ_F_FIXED_FILE_BIT
),
556 /* drain existing IO first */
557 REQ_F_IO_DRAIN
= BIT(REQ_F_IO_DRAIN_BIT
),
559 REQ_F_LINK
= BIT(REQ_F_LINK_BIT
),
560 /* doesn't sever on completion < 0 */
561 REQ_F_HARDLINK
= BIT(REQ_F_HARDLINK_BIT
),
563 REQ_F_FORCE_ASYNC
= BIT(REQ_F_FORCE_ASYNC_BIT
),
564 /* IOSQE_BUFFER_SELECT */
565 REQ_F_BUFFER_SELECT
= BIT(REQ_F_BUFFER_SELECT_BIT
),
568 REQ_F_LINK_HEAD
= BIT(REQ_F_LINK_HEAD_BIT
),
569 /* fail rest of links */
570 REQ_F_FAIL_LINK
= BIT(REQ_F_FAIL_LINK_BIT
),
571 /* on inflight list */
572 REQ_F_INFLIGHT
= BIT(REQ_F_INFLIGHT_BIT
),
573 /* read/write uses file position */
574 REQ_F_CUR_POS
= BIT(REQ_F_CUR_POS_BIT
),
575 /* must not punt to workers */
576 REQ_F_NOWAIT
= BIT(REQ_F_NOWAIT_BIT
),
577 /* has linked timeout */
578 REQ_F_LINK_TIMEOUT
= BIT(REQ_F_LINK_TIMEOUT_BIT
),
580 REQ_F_ISREG
= BIT(REQ_F_ISREG_BIT
),
581 /* completion under lock */
582 REQ_F_COMP_LOCKED
= BIT(REQ_F_COMP_LOCKED_BIT
),
584 REQ_F_NEED_CLEANUP
= BIT(REQ_F_NEED_CLEANUP_BIT
),
585 /* already went through poll handler */
586 REQ_F_POLLED
= BIT(REQ_F_POLLED_BIT
),
587 /* buffer already selected */
588 REQ_F_BUFFER_SELECTED
= BIT(REQ_F_BUFFER_SELECTED_BIT
),
589 /* doesn't need file table for this request */
590 REQ_F_NO_FILE_TABLE
= BIT(REQ_F_NO_FILE_TABLE_BIT
),
591 /* io_wq_work is initialized */
592 REQ_F_WORK_INITIALIZED
= BIT(REQ_F_WORK_INITIALIZED_BIT
),
593 /* req->task is refcounted */
594 REQ_F_TASK_PINNED
= BIT(REQ_F_TASK_PINNED_BIT
),
598 struct io_poll_iocb poll
;
599 struct io_poll_iocb
*double_poll
;
603 * NOTE! Each of the iocb union members has the file pointer
604 * as the first entry in their struct definition. So you can
605 * access the file pointer through any of the sub-structs,
606 * or directly as just 'ki_filp' in this struct.
612 struct io_poll_iocb poll
;
613 struct io_accept accept
;
615 struct io_cancel cancel
;
616 struct io_timeout timeout
;
617 struct io_connect connect
;
618 struct io_sr_msg sr_msg
;
620 struct io_close close
;
621 struct io_files_update files_update
;
622 struct io_fadvise fadvise
;
623 struct io_madvise madvise
;
624 struct io_epoll epoll
;
625 struct io_splice splice
;
626 struct io_provide_buf pbuf
;
627 struct io_statx statx
;
628 /* use only after cleaning per-op data, see io_clean_op() */
629 struct io_completion
compl;
632 struct io_async_ctx
*io
;
634 /* polled IO has completed */
640 struct io_ring_ctx
*ctx
;
643 struct task_struct
*task
;
646 struct list_head link_list
;
649 * 1. used with ctx->iopoll_list with reads/writes
650 * 2. to track reqs with ->files (see io_op_def::file_table)
652 struct list_head inflight_entry
;
654 struct percpu_ref
*fixed_file_refs
;
655 struct callback_head task_work
;
656 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
657 struct hlist_node hash_node
;
658 struct async_poll
*apoll
;
659 struct io_wq_work work
;
662 struct io_defer_entry
{
663 struct list_head list
;
664 struct io_kiocb
*req
;
668 #define IO_IOPOLL_BATCH 8
670 struct io_comp_state
{
672 struct list_head list
;
673 struct io_ring_ctx
*ctx
;
676 struct io_submit_state
{
677 struct blk_plug plug
;
680 * io_kiocb alloc cache
682 void *reqs
[IO_IOPOLL_BATCH
];
683 unsigned int free_reqs
;
686 * Batch completion logic
688 struct io_comp_state comp
;
691 * File reference cache
695 unsigned int has_refs
;
696 unsigned int ios_left
;
700 /* needs req->io allocated for deferral/async */
701 unsigned async_ctx
: 1;
702 /* needs current->mm setup, does mm access */
703 unsigned needs_mm
: 1;
704 /* needs req->file assigned */
705 unsigned needs_file
: 1;
706 /* don't fail if file grab fails */
707 unsigned needs_file_no_error
: 1;
708 /* hash wq insertion if file is a regular file */
709 unsigned hash_reg_file
: 1;
710 /* unbound wq insertion if file is a non-regular file */
711 unsigned unbound_nonreg_file
: 1;
712 /* opcode is not supported by this kernel */
713 unsigned not_supported
: 1;
714 /* needs file table */
715 unsigned file_table
: 1;
717 unsigned needs_fs
: 1;
718 /* set if opcode supports polled "wait" */
720 unsigned pollout
: 1;
721 /* op supports buffer selection */
722 unsigned buffer_select
: 1;
723 unsigned needs_fsize
: 1;
726 static const struct io_op_def io_op_defs
[] = {
727 [IORING_OP_NOP
] = {},
728 [IORING_OP_READV
] = {
732 .unbound_nonreg_file
= 1,
736 [IORING_OP_WRITEV
] = {
741 .unbound_nonreg_file
= 1,
745 [IORING_OP_FSYNC
] = {
748 [IORING_OP_READ_FIXED
] = {
750 .unbound_nonreg_file
= 1,
753 [IORING_OP_WRITE_FIXED
] = {
756 .unbound_nonreg_file
= 1,
760 [IORING_OP_POLL_ADD
] = {
762 .unbound_nonreg_file
= 1,
764 [IORING_OP_POLL_REMOVE
] = {},
765 [IORING_OP_SYNC_FILE_RANGE
] = {
768 [IORING_OP_SENDMSG
] = {
772 .unbound_nonreg_file
= 1,
776 [IORING_OP_RECVMSG
] = {
780 .unbound_nonreg_file
= 1,
785 [IORING_OP_TIMEOUT
] = {
789 [IORING_OP_TIMEOUT_REMOVE
] = {},
790 [IORING_OP_ACCEPT
] = {
793 .unbound_nonreg_file
= 1,
797 [IORING_OP_ASYNC_CANCEL
] = {},
798 [IORING_OP_LINK_TIMEOUT
] = {
802 [IORING_OP_CONNECT
] = {
806 .unbound_nonreg_file
= 1,
809 [IORING_OP_FALLOCATE
] = {
813 [IORING_OP_OPENAT
] = {
817 [IORING_OP_CLOSE
] = {
819 .needs_file_no_error
= 1,
822 [IORING_OP_FILES_UPDATE
] = {
826 [IORING_OP_STATX
] = {
834 .unbound_nonreg_file
= 1,
838 [IORING_OP_WRITE
] = {
841 .unbound_nonreg_file
= 1,
845 [IORING_OP_FADVISE
] = {
848 [IORING_OP_MADVISE
] = {
854 .unbound_nonreg_file
= 1,
860 .unbound_nonreg_file
= 1,
864 [IORING_OP_OPENAT2
] = {
868 [IORING_OP_EPOLL_CTL
] = {
869 .unbound_nonreg_file
= 1,
872 [IORING_OP_SPLICE
] = {
875 .unbound_nonreg_file
= 1,
877 [IORING_OP_PROVIDE_BUFFERS
] = {},
878 [IORING_OP_REMOVE_BUFFERS
] = {},
882 .unbound_nonreg_file
= 1,
886 enum io_mem_account
{
891 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
892 struct io_comp_state
*cs
);
893 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
);
894 static void io_put_req(struct io_kiocb
*req
);
895 static void io_double_put_req(struct io_kiocb
*req
);
896 static void __io_double_put_req(struct io_kiocb
*req
);
897 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
);
898 static void __io_queue_linked_timeout(struct io_kiocb
*req
);
899 static void io_queue_linked_timeout(struct io_kiocb
*req
);
900 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
901 struct io_uring_files_update
*ip
,
903 static int io_prep_work_files(struct io_kiocb
*req
);
904 static void __io_clean_op(struct io_kiocb
*req
);
905 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
906 int fd
, struct file
**out_file
, bool fixed
);
907 static void __io_queue_sqe(struct io_kiocb
*req
,
908 const struct io_uring_sqe
*sqe
,
909 struct io_comp_state
*cs
);
910 static void io_file_put_work(struct work_struct
*work
);
912 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
913 struct iovec
**iovec
, struct iov_iter
*iter
,
915 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
916 const struct iovec
*fast_iov
,
917 struct iov_iter
*iter
, bool force
);
919 static struct kmem_cache
*req_cachep
;
921 static const struct file_operations io_uring_fops
;
923 struct sock
*io_uring_get_socket(struct file
*file
)
925 #if defined(CONFIG_UNIX)
926 if (file
->f_op
== &io_uring_fops
) {
927 struct io_ring_ctx
*ctx
= file
->private_data
;
929 return ctx
->ring_sock
->sk
;
934 EXPORT_SYMBOL(io_uring_get_socket
);
936 static void io_get_req_task(struct io_kiocb
*req
)
938 if (req
->flags
& REQ_F_TASK_PINNED
)
940 get_task_struct(req
->task
);
941 req
->flags
|= REQ_F_TASK_PINNED
;
944 static inline void io_clean_op(struct io_kiocb
*req
)
946 if (req
->flags
& (REQ_F_NEED_CLEANUP
| REQ_F_BUFFER_SELECTED
|
951 /* not idempotent -- it doesn't clear REQ_F_TASK_PINNED */
952 static void __io_put_req_task(struct io_kiocb
*req
)
954 if (req
->flags
& REQ_F_TASK_PINNED
)
955 put_task_struct(req
->task
);
958 static void io_sq_thread_drop_mm(void)
960 struct mm_struct
*mm
= current
->mm
;
963 kthread_unuse_mm(mm
);
968 static int __io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
)
971 if (unlikely(!(ctx
->flags
& IORING_SETUP_SQPOLL
) ||
972 !mmget_not_zero(ctx
->sqo_mm
)))
974 kthread_use_mm(ctx
->sqo_mm
);
980 static int io_sq_thread_acquire_mm(struct io_ring_ctx
*ctx
,
981 struct io_kiocb
*req
)
983 if (!io_op_defs
[req
->opcode
].needs_mm
)
985 return __io_sq_thread_acquire_mm(ctx
);
988 static inline void req_set_fail_links(struct io_kiocb
*req
)
990 if ((req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) == REQ_F_LINK
)
991 req
->flags
|= REQ_F_FAIL_LINK
;
995 * Note: must call io_req_init_async() for the first time you
996 * touch any members of io_wq_work.
998 static inline void io_req_init_async(struct io_kiocb
*req
)
1000 if (req
->flags
& REQ_F_WORK_INITIALIZED
)
1003 memset(&req
->work
, 0, sizeof(req
->work
));
1004 req
->flags
|= REQ_F_WORK_INITIALIZED
;
1007 static inline bool io_async_submit(struct io_ring_ctx
*ctx
)
1009 return ctx
->flags
& IORING_SETUP_SQPOLL
;
1012 static void io_ring_ctx_ref_free(struct percpu_ref
*ref
)
1014 struct io_ring_ctx
*ctx
= container_of(ref
, struct io_ring_ctx
, refs
);
1016 complete(&ctx
->ref_comp
);
1019 static inline bool io_is_timeout_noseq(struct io_kiocb
*req
)
1021 return !req
->timeout
.off
;
1024 static struct io_ring_ctx
*io_ring_ctx_alloc(struct io_uring_params
*p
)
1026 struct io_ring_ctx
*ctx
;
1029 ctx
= kzalloc(sizeof(*ctx
), GFP_KERNEL
);
1033 ctx
->fallback_req
= kmem_cache_alloc(req_cachep
, GFP_KERNEL
);
1034 if (!ctx
->fallback_req
)
1038 * Use 5 bits less than the max cq entries, that should give us around
1039 * 32 entries per hash list if totally full and uniformly spread.
1041 hash_bits
= ilog2(p
->cq_entries
);
1045 ctx
->cancel_hash_bits
= hash_bits
;
1046 ctx
->cancel_hash
= kmalloc((1U << hash_bits
) * sizeof(struct hlist_head
),
1048 if (!ctx
->cancel_hash
)
1050 __hash_init(ctx
->cancel_hash
, 1U << hash_bits
);
1052 if (percpu_ref_init(&ctx
->refs
, io_ring_ctx_ref_free
,
1053 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
))
1056 ctx
->flags
= p
->flags
;
1057 init_waitqueue_head(&ctx
->sqo_wait
);
1058 init_waitqueue_head(&ctx
->cq_wait
);
1059 INIT_LIST_HEAD(&ctx
->cq_overflow_list
);
1060 init_completion(&ctx
->ref_comp
);
1061 init_completion(&ctx
->sq_thread_comp
);
1062 idr_init(&ctx
->io_buffer_idr
);
1063 idr_init(&ctx
->personality_idr
);
1064 mutex_init(&ctx
->uring_lock
);
1065 init_waitqueue_head(&ctx
->wait
);
1066 spin_lock_init(&ctx
->completion_lock
);
1067 INIT_LIST_HEAD(&ctx
->iopoll_list
);
1068 INIT_LIST_HEAD(&ctx
->defer_list
);
1069 INIT_LIST_HEAD(&ctx
->timeout_list
);
1070 init_waitqueue_head(&ctx
->inflight_wait
);
1071 spin_lock_init(&ctx
->inflight_lock
);
1072 INIT_LIST_HEAD(&ctx
->inflight_list
);
1073 INIT_DELAYED_WORK(&ctx
->file_put_work
, io_file_put_work
);
1074 init_llist_head(&ctx
->file_put_llist
);
1077 if (ctx
->fallback_req
)
1078 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
1079 kfree(ctx
->cancel_hash
);
1084 static bool req_need_defer(struct io_kiocb
*req
, u32 seq
)
1086 if (unlikely(req
->flags
& REQ_F_IO_DRAIN
)) {
1087 struct io_ring_ctx
*ctx
= req
->ctx
;
1089 return seq
!= ctx
->cached_cq_tail
1090 + atomic_read(&ctx
->cached_cq_overflow
);
1096 static void __io_commit_cqring(struct io_ring_ctx
*ctx
)
1098 struct io_rings
*rings
= ctx
->rings
;
1100 /* order cqe stores with ring update */
1101 smp_store_release(&rings
->cq
.tail
, ctx
->cached_cq_tail
);
1103 if (wq_has_sleeper(&ctx
->cq_wait
)) {
1104 wake_up_interruptible(&ctx
->cq_wait
);
1105 kill_fasync(&ctx
->cq_fasync
, SIGIO
, POLL_IN
);
1110 * Returns true if we need to defer file table putting. This can only happen
1111 * from the error path with REQ_F_COMP_LOCKED set.
1113 static bool io_req_clean_work(struct io_kiocb
*req
)
1115 if (!(req
->flags
& REQ_F_WORK_INITIALIZED
))
1118 req
->flags
&= ~REQ_F_WORK_INITIALIZED
;
1121 mmdrop(req
->work
.mm
);
1122 req
->work
.mm
= NULL
;
1124 if (req
->work
.creds
) {
1125 put_cred(req
->work
.creds
);
1126 req
->work
.creds
= NULL
;
1129 struct fs_struct
*fs
= req
->work
.fs
;
1131 if (req
->flags
& REQ_F_COMP_LOCKED
)
1134 spin_lock(&req
->work
.fs
->lock
);
1137 spin_unlock(&req
->work
.fs
->lock
);
1140 req
->work
.fs
= NULL
;
1146 static void io_prep_async_work(struct io_kiocb
*req
)
1148 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
1150 io_req_init_async(req
);
1152 if (req
->flags
& REQ_F_ISREG
) {
1153 if (def
->hash_reg_file
)
1154 io_wq_hash_work(&req
->work
, file_inode(req
->file
));
1156 if (def
->unbound_nonreg_file
)
1157 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
1159 if (!req
->work
.mm
&& def
->needs_mm
) {
1160 mmgrab(current
->mm
);
1161 req
->work
.mm
= current
->mm
;
1163 if (!req
->work
.creds
)
1164 req
->work
.creds
= get_current_cred();
1165 if (!req
->work
.fs
&& def
->needs_fs
) {
1166 spin_lock(¤t
->fs
->lock
);
1167 if (!current
->fs
->in_exec
) {
1168 req
->work
.fs
= current
->fs
;
1169 req
->work
.fs
->users
++;
1171 req
->work
.flags
|= IO_WQ_WORK_CANCEL
;
1173 spin_unlock(¤t
->fs
->lock
);
1175 if (def
->needs_fsize
)
1176 req
->work
.fsize
= rlimit(RLIMIT_FSIZE
);
1178 req
->work
.fsize
= RLIM_INFINITY
;
1181 static void io_prep_async_link(struct io_kiocb
*req
)
1183 struct io_kiocb
*cur
;
1185 io_prep_async_work(req
);
1186 if (req
->flags
& REQ_F_LINK_HEAD
)
1187 list_for_each_entry(cur
, &req
->link_list
, link_list
)
1188 io_prep_async_work(cur
);
1191 static struct io_kiocb
*__io_queue_async_work(struct io_kiocb
*req
)
1193 struct io_ring_ctx
*ctx
= req
->ctx
;
1194 struct io_kiocb
*link
= io_prep_linked_timeout(req
);
1196 trace_io_uring_queue_async_work(ctx
, io_wq_is_hashed(&req
->work
), req
,
1197 &req
->work
, req
->flags
);
1198 io_wq_enqueue(ctx
->io_wq
, &req
->work
);
1202 static void io_queue_async_work(struct io_kiocb
*req
)
1204 struct io_kiocb
*link
;
1206 /* init ->work of the whole link before punting */
1207 io_prep_async_link(req
);
1208 link
= __io_queue_async_work(req
);
1211 io_queue_linked_timeout(link
);
1214 static void io_kill_timeout(struct io_kiocb
*req
)
1218 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1220 atomic_set(&req
->ctx
->cq_timeouts
,
1221 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
1222 list_del_init(&req
->timeout
.list
);
1223 req
->flags
|= REQ_F_COMP_LOCKED
;
1224 io_cqring_fill_event(req
, 0);
1229 static void io_kill_timeouts(struct io_ring_ctx
*ctx
)
1231 struct io_kiocb
*req
, *tmp
;
1233 spin_lock_irq(&ctx
->completion_lock
);
1234 list_for_each_entry_safe(req
, tmp
, &ctx
->timeout_list
, timeout
.list
)
1235 io_kill_timeout(req
);
1236 spin_unlock_irq(&ctx
->completion_lock
);
1239 static void __io_queue_deferred(struct io_ring_ctx
*ctx
)
1242 struct io_defer_entry
*de
= list_first_entry(&ctx
->defer_list
,
1243 struct io_defer_entry
, list
);
1244 struct io_kiocb
*link
;
1246 if (req_need_defer(de
->req
, de
->seq
))
1248 list_del_init(&de
->list
);
1249 /* punt-init is done before queueing for defer */
1250 link
= __io_queue_async_work(de
->req
);
1252 __io_queue_linked_timeout(link
);
1253 /* drop submission reference */
1254 link
->flags
|= REQ_F_COMP_LOCKED
;
1258 } while (!list_empty(&ctx
->defer_list
));
1261 static void io_flush_timeouts(struct io_ring_ctx
*ctx
)
1263 while (!list_empty(&ctx
->timeout_list
)) {
1264 struct io_kiocb
*req
= list_first_entry(&ctx
->timeout_list
,
1265 struct io_kiocb
, timeout
.list
);
1267 if (io_is_timeout_noseq(req
))
1269 if (req
->timeout
.target_seq
!= ctx
->cached_cq_tail
1270 - atomic_read(&ctx
->cq_timeouts
))
1273 list_del_init(&req
->timeout
.list
);
1274 io_kill_timeout(req
);
1278 static void io_commit_cqring(struct io_ring_ctx
*ctx
)
1280 io_flush_timeouts(ctx
);
1281 __io_commit_cqring(ctx
);
1283 if (unlikely(!list_empty(&ctx
->defer_list
)))
1284 __io_queue_deferred(ctx
);
1287 static struct io_uring_cqe
*io_get_cqring(struct io_ring_ctx
*ctx
)
1289 struct io_rings
*rings
= ctx
->rings
;
1292 tail
= ctx
->cached_cq_tail
;
1294 * writes to the cq entry need to come after reading head; the
1295 * control dependency is enough as we're using WRITE_ONCE to
1298 if (tail
- READ_ONCE(rings
->cq
.head
) == rings
->cq_ring_entries
)
1301 ctx
->cached_cq_tail
++;
1302 return &rings
->cqes
[tail
& ctx
->cq_mask
];
1305 static inline bool io_should_trigger_evfd(struct io_ring_ctx
*ctx
)
1309 if (READ_ONCE(ctx
->rings
->cq_flags
) & IORING_CQ_EVENTFD_DISABLED
)
1311 if (!ctx
->eventfd_async
)
1313 return io_wq_current_is_worker();
1316 static void io_cqring_ev_posted(struct io_ring_ctx
*ctx
)
1318 if (waitqueue_active(&ctx
->wait
))
1319 wake_up(&ctx
->wait
);
1320 if (waitqueue_active(&ctx
->sqo_wait
))
1321 wake_up(&ctx
->sqo_wait
);
1322 if (io_should_trigger_evfd(ctx
))
1323 eventfd_signal(ctx
->cq_ev_fd
, 1);
1326 static void io_cqring_mark_overflow(struct io_ring_ctx
*ctx
)
1328 if (list_empty(&ctx
->cq_overflow_list
)) {
1329 clear_bit(0, &ctx
->sq_check_overflow
);
1330 clear_bit(0, &ctx
->cq_check_overflow
);
1331 ctx
->rings
->sq_flags
&= ~IORING_SQ_CQ_OVERFLOW
;
1335 /* Returns true if there are no backlogged entries after the flush */
1336 static bool io_cqring_overflow_flush(struct io_ring_ctx
*ctx
, bool force
)
1338 struct io_rings
*rings
= ctx
->rings
;
1339 struct io_uring_cqe
*cqe
;
1340 struct io_kiocb
*req
;
1341 unsigned long flags
;
1345 if (list_empty_careful(&ctx
->cq_overflow_list
))
1347 if ((ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
) ==
1348 rings
->cq_ring_entries
))
1352 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1354 /* if force is set, the ring is going away. always drop after that */
1356 ctx
->cq_overflow_flushed
= 1;
1359 while (!list_empty(&ctx
->cq_overflow_list
)) {
1360 cqe
= io_get_cqring(ctx
);
1364 req
= list_first_entry(&ctx
->cq_overflow_list
, struct io_kiocb
,
1366 list_move(&req
->compl.list
, &list
);
1368 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1369 WRITE_ONCE(cqe
->res
, req
->result
);
1370 WRITE_ONCE(cqe
->flags
, req
->compl.cflags
);
1372 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1373 atomic_inc_return(&ctx
->cached_cq_overflow
));
1377 io_commit_cqring(ctx
);
1378 io_cqring_mark_overflow(ctx
);
1380 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1381 io_cqring_ev_posted(ctx
);
1383 while (!list_empty(&list
)) {
1384 req
= list_first_entry(&list
, struct io_kiocb
, compl.list
);
1385 list_del(&req
->compl.list
);
1392 static void __io_cqring_fill_event(struct io_kiocb
*req
, long res
, long cflags
)
1394 struct io_ring_ctx
*ctx
= req
->ctx
;
1395 struct io_uring_cqe
*cqe
;
1397 trace_io_uring_complete(ctx
, req
->user_data
, res
);
1400 * If we can't get a cq entry, userspace overflowed the
1401 * submission (by quite a lot). Increment the overflow count in
1404 cqe
= io_get_cqring(ctx
);
1406 WRITE_ONCE(cqe
->user_data
, req
->user_data
);
1407 WRITE_ONCE(cqe
->res
, res
);
1408 WRITE_ONCE(cqe
->flags
, cflags
);
1409 } else if (ctx
->cq_overflow_flushed
) {
1410 WRITE_ONCE(ctx
->rings
->cq_overflow
,
1411 atomic_inc_return(&ctx
->cached_cq_overflow
));
1413 if (list_empty(&ctx
->cq_overflow_list
)) {
1414 set_bit(0, &ctx
->sq_check_overflow
);
1415 set_bit(0, &ctx
->cq_check_overflow
);
1416 ctx
->rings
->sq_flags
|= IORING_SQ_CQ_OVERFLOW
;
1420 req
->compl.cflags
= cflags
;
1421 refcount_inc(&req
->refs
);
1422 list_add_tail(&req
->compl.list
, &ctx
->cq_overflow_list
);
1426 static void io_cqring_fill_event(struct io_kiocb
*req
, long res
)
1428 __io_cqring_fill_event(req
, res
, 0);
1431 static void io_cqring_add_event(struct io_kiocb
*req
, long res
, long cflags
)
1433 struct io_ring_ctx
*ctx
= req
->ctx
;
1434 unsigned long flags
;
1436 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1437 __io_cqring_fill_event(req
, res
, cflags
);
1438 io_commit_cqring(ctx
);
1439 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1441 io_cqring_ev_posted(ctx
);
1444 static void io_submit_flush_completions(struct io_comp_state
*cs
)
1446 struct io_ring_ctx
*ctx
= cs
->ctx
;
1448 spin_lock_irq(&ctx
->completion_lock
);
1449 while (!list_empty(&cs
->list
)) {
1450 struct io_kiocb
*req
;
1452 req
= list_first_entry(&cs
->list
, struct io_kiocb
, compl.list
);
1453 list_del(&req
->compl.list
);
1454 __io_cqring_fill_event(req
, req
->result
, req
->compl.cflags
);
1455 if (!(req
->flags
& REQ_F_LINK_HEAD
)) {
1456 req
->flags
|= REQ_F_COMP_LOCKED
;
1459 spin_unlock_irq(&ctx
->completion_lock
);
1461 spin_lock_irq(&ctx
->completion_lock
);
1464 io_commit_cqring(ctx
);
1465 spin_unlock_irq(&ctx
->completion_lock
);
1467 io_cqring_ev_posted(ctx
);
1471 static void __io_req_complete(struct io_kiocb
*req
, long res
, unsigned cflags
,
1472 struct io_comp_state
*cs
)
1475 io_cqring_add_event(req
, res
, cflags
);
1480 req
->compl.cflags
= cflags
;
1481 list_add_tail(&req
->compl.list
, &cs
->list
);
1483 io_submit_flush_completions(cs
);
1487 static void io_req_complete(struct io_kiocb
*req
, long res
)
1489 __io_req_complete(req
, res
, 0, NULL
);
1492 static inline bool io_is_fallback_req(struct io_kiocb
*req
)
1494 return req
== (struct io_kiocb
*)
1495 ((unsigned long) req
->ctx
->fallback_req
& ~1UL);
1498 static struct io_kiocb
*io_get_fallback_req(struct io_ring_ctx
*ctx
)
1500 struct io_kiocb
*req
;
1502 req
= ctx
->fallback_req
;
1503 if (!test_and_set_bit_lock(0, (unsigned long *) &ctx
->fallback_req
))
1509 static struct io_kiocb
*io_alloc_req(struct io_ring_ctx
*ctx
,
1510 struct io_submit_state
*state
)
1512 gfp_t gfp
= GFP_KERNEL
| __GFP_NOWARN
;
1513 struct io_kiocb
*req
;
1515 if (!state
->free_reqs
) {
1519 sz
= min_t(size_t, state
->ios_left
, ARRAY_SIZE(state
->reqs
));
1520 ret
= kmem_cache_alloc_bulk(req_cachep
, gfp
, sz
, state
->reqs
);
1523 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1524 * retry single alloc to be on the safe side.
1526 if (unlikely(ret
<= 0)) {
1527 state
->reqs
[0] = kmem_cache_alloc(req_cachep
, gfp
);
1528 if (!state
->reqs
[0])
1532 state
->free_reqs
= ret
- 1;
1533 req
= state
->reqs
[ret
- 1];
1536 req
= state
->reqs
[state
->free_reqs
];
1541 return io_get_fallback_req(ctx
);
1544 static inline void io_put_file(struct io_kiocb
*req
, struct file
*file
,
1548 percpu_ref_put(req
->fixed_file_refs
);
1553 static bool io_dismantle_req(struct io_kiocb
*req
)
1560 io_put_file(req
, req
->file
, (req
->flags
& REQ_F_FIXED_FILE
));
1562 return io_req_clean_work(req
);
1565 static void __io_free_req_finish(struct io_kiocb
*req
)
1567 struct io_ring_ctx
*ctx
= req
->ctx
;
1569 __io_put_req_task(req
);
1570 if (likely(!io_is_fallback_req(req
)))
1571 kmem_cache_free(req_cachep
, req
);
1573 clear_bit_unlock(0, (unsigned long *) &ctx
->fallback_req
);
1574 percpu_ref_put(&ctx
->refs
);
1577 static void io_req_task_file_table_put(struct callback_head
*cb
)
1579 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
1580 struct fs_struct
*fs
= req
->work
.fs
;
1582 spin_lock(&req
->work
.fs
->lock
);
1585 spin_unlock(&req
->work
.fs
->lock
);
1588 req
->work
.fs
= NULL
;
1589 __io_free_req_finish(req
);
1592 static void __io_free_req(struct io_kiocb
*req
)
1594 if (!io_dismantle_req(req
)) {
1595 __io_free_req_finish(req
);
1599 init_task_work(&req
->task_work
, io_req_task_file_table_put
);
1600 ret
= task_work_add(req
->task
, &req
->task_work
, TWA_RESUME
);
1601 if (unlikely(ret
)) {
1602 struct task_struct
*tsk
;
1604 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
1605 task_work_add(tsk
, &req
->task_work
, 0);
1610 static bool io_link_cancel_timeout(struct io_kiocb
*req
)
1612 struct io_ring_ctx
*ctx
= req
->ctx
;
1615 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
1617 io_cqring_fill_event(req
, -ECANCELED
);
1618 io_commit_cqring(ctx
);
1619 req
->flags
&= ~REQ_F_LINK_HEAD
;
1627 static bool __io_kill_linked_timeout(struct io_kiocb
*req
)
1629 struct io_kiocb
*link
;
1632 if (list_empty(&req
->link_list
))
1634 link
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1635 if (link
->opcode
!= IORING_OP_LINK_TIMEOUT
)
1638 list_del_init(&link
->link_list
);
1639 link
->flags
|= REQ_F_COMP_LOCKED
;
1640 wake_ev
= io_link_cancel_timeout(link
);
1641 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1645 static void io_kill_linked_timeout(struct io_kiocb
*req
)
1647 struct io_ring_ctx
*ctx
= req
->ctx
;
1650 if (!(req
->flags
& REQ_F_COMP_LOCKED
)) {
1651 unsigned long flags
;
1653 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1654 wake_ev
= __io_kill_linked_timeout(req
);
1655 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1657 wake_ev
= __io_kill_linked_timeout(req
);
1661 io_cqring_ev_posted(ctx
);
1664 static struct io_kiocb
*io_req_link_next(struct io_kiocb
*req
)
1666 struct io_kiocb
*nxt
;
1669 * The list should never be empty when we are called here. But could
1670 * potentially happen if the chain is messed up, check to be on the
1673 if (unlikely(list_empty(&req
->link_list
)))
1676 nxt
= list_first_entry(&req
->link_list
, struct io_kiocb
, link_list
);
1677 list_del_init(&req
->link_list
);
1678 if (!list_empty(&nxt
->link_list
))
1679 nxt
->flags
|= REQ_F_LINK_HEAD
;
1684 * Called if REQ_F_LINK_HEAD is set, and we fail the head request
1686 static void __io_fail_links(struct io_kiocb
*req
)
1688 struct io_ring_ctx
*ctx
= req
->ctx
;
1690 while (!list_empty(&req
->link_list
)) {
1691 struct io_kiocb
*link
= list_first_entry(&req
->link_list
,
1692 struct io_kiocb
, link_list
);
1694 list_del_init(&link
->link_list
);
1695 trace_io_uring_fail_link(req
, link
);
1697 io_cqring_fill_event(link
, -ECANCELED
);
1698 link
->flags
|= REQ_F_COMP_LOCKED
;
1699 __io_double_put_req(link
);
1700 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
1703 io_commit_cqring(ctx
);
1704 io_cqring_ev_posted(ctx
);
1707 static void io_fail_links(struct io_kiocb
*req
)
1709 struct io_ring_ctx
*ctx
= req
->ctx
;
1711 if (!(req
->flags
& REQ_F_COMP_LOCKED
)) {
1712 unsigned long flags
;
1714 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
1715 __io_fail_links(req
);
1716 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
1718 __io_fail_links(req
);
1721 io_cqring_ev_posted(ctx
);
1724 static struct io_kiocb
*__io_req_find_next(struct io_kiocb
*req
)
1726 req
->flags
&= ~REQ_F_LINK_HEAD
;
1727 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
1728 io_kill_linked_timeout(req
);
1731 * If LINK is set, we have dependent requests in this chain. If we
1732 * didn't fail this request, queue the first one up, moving any other
1733 * dependencies to the next request. In case of failure, fail the rest
1736 if (likely(!(req
->flags
& REQ_F_FAIL_LINK
)))
1737 return io_req_link_next(req
);
1742 static struct io_kiocb
*io_req_find_next(struct io_kiocb
*req
)
1744 if (likely(!(req
->flags
& REQ_F_LINK_HEAD
)))
1746 return __io_req_find_next(req
);
1749 static int io_req_task_work_add(struct io_kiocb
*req
, struct callback_head
*cb
)
1751 struct task_struct
*tsk
= req
->task
;
1752 struct io_ring_ctx
*ctx
= req
->ctx
;
1756 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
1757 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
1758 * processing task_work. There's no reliable way to tell if TWA_RESUME
1762 if (!(ctx
->flags
& IORING_SETUP_SQPOLL
))
1763 notify
= TWA_SIGNAL
;
1765 ret
= task_work_add(tsk
, cb
, notify
);
1767 wake_up_process(tsk
);
1772 static void __io_req_task_cancel(struct io_kiocb
*req
, int error
)
1774 struct io_ring_ctx
*ctx
= req
->ctx
;
1776 spin_lock_irq(&ctx
->completion_lock
);
1777 io_cqring_fill_event(req
, error
);
1778 io_commit_cqring(ctx
);
1779 spin_unlock_irq(&ctx
->completion_lock
);
1781 io_cqring_ev_posted(ctx
);
1782 req_set_fail_links(req
);
1783 io_double_put_req(req
);
1786 static void io_req_task_cancel(struct callback_head
*cb
)
1788 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
1790 __io_req_task_cancel(req
, -ECANCELED
);
1793 static void __io_req_task_submit(struct io_kiocb
*req
)
1795 struct io_ring_ctx
*ctx
= req
->ctx
;
1797 if (!__io_sq_thread_acquire_mm(ctx
)) {
1798 mutex_lock(&ctx
->uring_lock
);
1799 __io_queue_sqe(req
, NULL
, NULL
);
1800 mutex_unlock(&ctx
->uring_lock
);
1802 __io_req_task_cancel(req
, -EFAULT
);
1806 static void io_req_task_submit(struct callback_head
*cb
)
1808 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
1809 struct io_ring_ctx
*ctx
= req
->ctx
;
1811 __io_req_task_submit(req
);
1812 percpu_ref_put(&ctx
->refs
);
1815 static void io_req_task_queue(struct io_kiocb
*req
)
1819 init_task_work(&req
->task_work
, io_req_task_submit
);
1820 percpu_ref_get(&req
->ctx
->refs
);
1822 ret
= io_req_task_work_add(req
, &req
->task_work
);
1823 if (unlikely(ret
)) {
1824 struct task_struct
*tsk
;
1826 init_task_work(&req
->task_work
, io_req_task_cancel
);
1827 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
1828 task_work_add(tsk
, &req
->task_work
, 0);
1829 wake_up_process(tsk
);
1833 static void io_queue_next(struct io_kiocb
*req
)
1835 struct io_kiocb
*nxt
= io_req_find_next(req
);
1838 io_req_task_queue(nxt
);
1841 static void io_free_req(struct io_kiocb
*req
)
1848 void *reqs
[IO_IOPOLL_BATCH
];
1851 struct task_struct
*task
;
1855 static inline void io_init_req_batch(struct req_batch
*rb
)
1862 static void __io_req_free_batch_flush(struct io_ring_ctx
*ctx
,
1863 struct req_batch
*rb
)
1865 kmem_cache_free_bulk(req_cachep
, rb
->to_free
, rb
->reqs
);
1866 percpu_ref_put_many(&ctx
->refs
, rb
->to_free
);
1870 static void io_req_free_batch_finish(struct io_ring_ctx
*ctx
,
1871 struct req_batch
*rb
)
1874 __io_req_free_batch_flush(ctx
, rb
);
1876 put_task_struct_many(rb
->task
, rb
->task_refs
);
1881 static void io_req_free_batch(struct req_batch
*rb
, struct io_kiocb
*req
)
1883 if (unlikely(io_is_fallback_req(req
))) {
1887 if (req
->flags
& REQ_F_LINK_HEAD
)
1890 if (req
->flags
& REQ_F_TASK_PINNED
) {
1891 if (req
->task
!= rb
->task
) {
1893 put_task_struct_many(rb
->task
, rb
->task_refs
);
1894 rb
->task
= req
->task
;
1898 req
->flags
&= ~REQ_F_TASK_PINNED
;
1901 WARN_ON_ONCE(io_dismantle_req(req
));
1902 rb
->reqs
[rb
->to_free
++] = req
;
1903 if (unlikely(rb
->to_free
== ARRAY_SIZE(rb
->reqs
)))
1904 __io_req_free_batch_flush(req
->ctx
, rb
);
1908 * Drop reference to request, return next in chain (if there is one) if this
1909 * was the last reference to this request.
1911 static struct io_kiocb
*io_put_req_find_next(struct io_kiocb
*req
)
1913 struct io_kiocb
*nxt
= NULL
;
1915 if (refcount_dec_and_test(&req
->refs
)) {
1916 nxt
= io_req_find_next(req
);
1922 static void io_put_req(struct io_kiocb
*req
)
1924 if (refcount_dec_and_test(&req
->refs
))
1928 static struct io_wq_work
*io_steal_work(struct io_kiocb
*req
)
1930 struct io_kiocb
*nxt
;
1933 * A ref is owned by io-wq in which context we're. So, if that's the
1934 * last one, it's safe to steal next work. False negatives are Ok,
1935 * it just will be re-punted async in io_put_work()
1937 if (refcount_read(&req
->refs
) != 1)
1940 nxt
= io_req_find_next(req
);
1941 return nxt
? &nxt
->work
: NULL
;
1945 * Must only be used if we don't need to care about links, usually from
1946 * within the completion handling itself.
1948 static void __io_double_put_req(struct io_kiocb
*req
)
1950 /* drop both submit and complete references */
1951 if (refcount_sub_and_test(2, &req
->refs
))
1955 static void io_double_put_req(struct io_kiocb
*req
)
1957 /* drop both submit and complete references */
1958 if (refcount_sub_and_test(2, &req
->refs
))
1962 static unsigned io_cqring_events(struct io_ring_ctx
*ctx
, bool noflush
)
1964 struct io_rings
*rings
= ctx
->rings
;
1966 if (test_bit(0, &ctx
->cq_check_overflow
)) {
1968 * noflush == true is from the waitqueue handler, just ensure
1969 * we wake up the task, and the next invocation will flush the
1970 * entries. We cannot safely to it from here.
1972 if (noflush
&& !list_empty(&ctx
->cq_overflow_list
))
1975 io_cqring_overflow_flush(ctx
, false);
1978 /* See comment at the top of this file */
1980 return ctx
->cached_cq_tail
- READ_ONCE(rings
->cq
.head
);
1983 static inline unsigned int io_sqring_entries(struct io_ring_ctx
*ctx
)
1985 struct io_rings
*rings
= ctx
->rings
;
1987 /* make sure SQ entry isn't read before tail */
1988 return smp_load_acquire(&rings
->sq
.tail
) - ctx
->cached_sq_head
;
1991 static unsigned int io_put_kbuf(struct io_kiocb
*req
, struct io_buffer
*kbuf
)
1993 unsigned int cflags
;
1995 cflags
= kbuf
->bid
<< IORING_CQE_BUFFER_SHIFT
;
1996 cflags
|= IORING_CQE_F_BUFFER
;
1997 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
2002 static inline unsigned int io_put_rw_kbuf(struct io_kiocb
*req
)
2004 struct io_buffer
*kbuf
;
2006 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2007 return io_put_kbuf(req
, kbuf
);
2010 static inline bool io_run_task_work(void)
2012 if (current
->task_works
) {
2013 __set_current_state(TASK_RUNNING
);
2021 static void io_iopoll_queue(struct list_head
*again
)
2023 struct io_kiocb
*req
;
2026 req
= list_first_entry(again
, struct io_kiocb
, inflight_entry
);
2027 list_del(&req
->inflight_entry
);
2028 __io_complete_rw(req
, -EAGAIN
, 0, NULL
);
2029 } while (!list_empty(again
));
2033 * Find and free completed poll iocbs
2035 static void io_iopoll_complete(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2036 struct list_head
*done
)
2038 struct req_batch rb
;
2039 struct io_kiocb
*req
;
2042 /* order with ->result store in io_complete_rw_iopoll() */
2045 io_init_req_batch(&rb
);
2046 while (!list_empty(done
)) {
2049 req
= list_first_entry(done
, struct io_kiocb
, inflight_entry
);
2050 if (READ_ONCE(req
->result
) == -EAGAIN
) {
2051 req
->iopoll_completed
= 0;
2052 list_move_tail(&req
->inflight_entry
, &again
);
2055 list_del(&req
->inflight_entry
);
2057 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2058 cflags
= io_put_rw_kbuf(req
);
2060 __io_cqring_fill_event(req
, req
->result
, cflags
);
2063 if (refcount_dec_and_test(&req
->refs
))
2064 io_req_free_batch(&rb
, req
);
2067 io_commit_cqring(ctx
);
2068 if (ctx
->flags
& IORING_SETUP_SQPOLL
)
2069 io_cqring_ev_posted(ctx
);
2070 io_req_free_batch_finish(ctx
, &rb
);
2072 if (!list_empty(&again
))
2073 io_iopoll_queue(&again
);
2076 static int io_do_iopoll(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2079 struct io_kiocb
*req
, *tmp
;
2085 * Only spin for completions if we don't have multiple devices hanging
2086 * off our complete list, and we're under the requested amount.
2088 spin
= !ctx
->poll_multi_file
&& *nr_events
< min
;
2091 list_for_each_entry_safe(req
, tmp
, &ctx
->iopoll_list
, inflight_entry
) {
2092 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2095 * Move completed and retryable entries to our local lists.
2096 * If we find a request that requires polling, break out
2097 * and complete those lists first, if we have entries there.
2099 if (READ_ONCE(req
->iopoll_completed
)) {
2100 list_move_tail(&req
->inflight_entry
, &done
);
2103 if (!list_empty(&done
))
2106 ret
= kiocb
->ki_filp
->f_op
->iopoll(kiocb
, spin
);
2110 /* iopoll may have completed current req */
2111 if (READ_ONCE(req
->iopoll_completed
))
2112 list_move_tail(&req
->inflight_entry
, &done
);
2119 if (!list_empty(&done
))
2120 io_iopoll_complete(ctx
, nr_events
, &done
);
2126 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2127 * non-spinning poll check - we'll still enter the driver poll loop, but only
2128 * as a non-spinning completion check.
2130 static int io_iopoll_getevents(struct io_ring_ctx
*ctx
, unsigned int *nr_events
,
2133 while (!list_empty(&ctx
->iopoll_list
) && !need_resched()) {
2136 ret
= io_do_iopoll(ctx
, nr_events
, min
);
2139 if (*nr_events
>= min
)
2147 * We can't just wait for polled events to come to us, we have to actively
2148 * find and complete them.
2150 static void io_iopoll_try_reap_events(struct io_ring_ctx
*ctx
)
2152 if (!(ctx
->flags
& IORING_SETUP_IOPOLL
))
2155 mutex_lock(&ctx
->uring_lock
);
2156 while (!list_empty(&ctx
->iopoll_list
)) {
2157 unsigned int nr_events
= 0;
2159 io_do_iopoll(ctx
, &nr_events
, 0);
2161 /* let it sleep and repeat later if can't complete a request */
2165 * Ensure we allow local-to-the-cpu processing to take place,
2166 * in this case we need to ensure that we reap all events.
2167 * Also let task_work, etc. to progress by releasing the mutex
2169 if (need_resched()) {
2170 mutex_unlock(&ctx
->uring_lock
);
2172 mutex_lock(&ctx
->uring_lock
);
2175 mutex_unlock(&ctx
->uring_lock
);
2178 static int io_iopoll_check(struct io_ring_ctx
*ctx
, long min
)
2180 unsigned int nr_events
= 0;
2181 int iters
= 0, ret
= 0;
2184 * We disallow the app entering submit/complete with polling, but we
2185 * still need to lock the ring to prevent racing with polled issue
2186 * that got punted to a workqueue.
2188 mutex_lock(&ctx
->uring_lock
);
2191 * Don't enter poll loop if we already have events pending.
2192 * If we do, we can potentially be spinning for commands that
2193 * already triggered a CQE (eg in error).
2195 if (io_cqring_events(ctx
, false))
2199 * If a submit got punted to a workqueue, we can have the
2200 * application entering polling for a command before it gets
2201 * issued. That app will hold the uring_lock for the duration
2202 * of the poll right here, so we need to take a breather every
2203 * now and then to ensure that the issue has a chance to add
2204 * the poll to the issued list. Otherwise we can spin here
2205 * forever, while the workqueue is stuck trying to acquire the
2208 if (!(++iters
& 7)) {
2209 mutex_unlock(&ctx
->uring_lock
);
2211 mutex_lock(&ctx
->uring_lock
);
2214 ret
= io_iopoll_getevents(ctx
, &nr_events
, min
);
2218 } while (min
&& !nr_events
&& !need_resched());
2220 mutex_unlock(&ctx
->uring_lock
);
2224 static void kiocb_end_write(struct io_kiocb
*req
)
2227 * Tell lockdep we inherited freeze protection from submission
2230 if (req
->flags
& REQ_F_ISREG
) {
2231 struct inode
*inode
= file_inode(req
->file
);
2233 __sb_writers_acquired(inode
->i_sb
, SB_FREEZE_WRITE
);
2235 file_end_write(req
->file
);
2238 static void io_complete_rw_common(struct kiocb
*kiocb
, long res
,
2239 struct io_comp_state
*cs
)
2241 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2244 if (kiocb
->ki_flags
& IOCB_WRITE
)
2245 kiocb_end_write(req
);
2247 if (res
!= req
->result
)
2248 req_set_fail_links(req
);
2249 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2250 cflags
= io_put_rw_kbuf(req
);
2251 __io_req_complete(req
, res
, cflags
, cs
);
2255 static bool io_resubmit_prep(struct io_kiocb
*req
, int error
)
2257 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
2258 ssize_t ret
= -ECANCELED
;
2259 struct iov_iter iter
;
2267 switch (req
->opcode
) {
2268 case IORING_OP_READV
:
2269 case IORING_OP_READ_FIXED
:
2270 case IORING_OP_READ
:
2273 case IORING_OP_WRITEV
:
2274 case IORING_OP_WRITE_FIXED
:
2275 case IORING_OP_WRITE
:
2279 printk_once(KERN_WARNING
"io_uring: bad opcode in resubmit %d\n",
2284 ret
= io_import_iovec(rw
, req
, &iovec
, &iter
, false);
2287 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, &iter
, false);
2292 req_set_fail_links(req
);
2293 io_req_complete(req
, ret
);
2297 static void io_rw_resubmit(struct callback_head
*cb
)
2299 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
2300 struct io_ring_ctx
*ctx
= req
->ctx
;
2303 err
= io_sq_thread_acquire_mm(ctx
, req
);
2305 if (io_resubmit_prep(req
, err
)) {
2306 refcount_inc(&req
->refs
);
2307 io_queue_async_work(req
);
2310 percpu_ref_put(&ctx
->refs
);
2314 static bool io_rw_reissue(struct io_kiocb
*req
, long res
)
2319 if ((res
!= -EAGAIN
&& res
!= -EOPNOTSUPP
) || io_wq_current_is_worker())
2322 init_task_work(&req
->task_work
, io_rw_resubmit
);
2323 percpu_ref_get(&req
->ctx
->refs
);
2325 ret
= io_req_task_work_add(req
, &req
->task_work
);
2332 static void __io_complete_rw(struct io_kiocb
*req
, long res
, long res2
,
2333 struct io_comp_state
*cs
)
2335 if (!io_rw_reissue(req
, res
))
2336 io_complete_rw_common(&req
->rw
.kiocb
, res
, cs
);
2339 static void io_complete_rw(struct kiocb
*kiocb
, long res
, long res2
)
2341 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2343 __io_complete_rw(req
, res
, res2
, NULL
);
2346 static void io_complete_rw_iopoll(struct kiocb
*kiocb
, long res
, long res2
)
2348 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2350 if (kiocb
->ki_flags
& IOCB_WRITE
)
2351 kiocb_end_write(req
);
2353 if (res
!= -EAGAIN
&& res
!= req
->result
)
2354 req_set_fail_links(req
);
2356 WRITE_ONCE(req
->result
, res
);
2357 /* order with io_poll_complete() checking ->result */
2359 WRITE_ONCE(req
->iopoll_completed
, 1);
2363 * After the iocb has been issued, it's safe to be found on the poll list.
2364 * Adding the kiocb to the list AFTER submission ensures that we don't
2365 * find it from a io_iopoll_getevents() thread before the issuer is done
2366 * accessing the kiocb cookie.
2368 static void io_iopoll_req_issued(struct io_kiocb
*req
)
2370 struct io_ring_ctx
*ctx
= req
->ctx
;
2373 * Track whether we have multiple files in our lists. This will impact
2374 * how we do polling eventually, not spinning if we're on potentially
2375 * different devices.
2377 if (list_empty(&ctx
->iopoll_list
)) {
2378 ctx
->poll_multi_file
= false;
2379 } else if (!ctx
->poll_multi_file
) {
2380 struct io_kiocb
*list_req
;
2382 list_req
= list_first_entry(&ctx
->iopoll_list
, struct io_kiocb
,
2384 if (list_req
->file
!= req
->file
)
2385 ctx
->poll_multi_file
= true;
2389 * For fast devices, IO may have already completed. If it has, add
2390 * it to the front so we find it first.
2392 if (READ_ONCE(req
->iopoll_completed
))
2393 list_add(&req
->inflight_entry
, &ctx
->iopoll_list
);
2395 list_add_tail(&req
->inflight_entry
, &ctx
->iopoll_list
);
2397 if ((ctx
->flags
& IORING_SETUP_SQPOLL
) &&
2398 wq_has_sleeper(&ctx
->sqo_wait
))
2399 wake_up(&ctx
->sqo_wait
);
2402 static void __io_state_file_put(struct io_submit_state
*state
)
2404 if (state
->has_refs
)
2405 fput_many(state
->file
, state
->has_refs
);
2409 static inline void io_state_file_put(struct io_submit_state
*state
)
2412 __io_state_file_put(state
);
2416 * Get as many references to a file as we have IOs left in this submission,
2417 * assuming most submissions are for one file, or at least that each file
2418 * has more than one submission.
2420 static struct file
*__io_file_get(struct io_submit_state
*state
, int fd
)
2426 if (state
->fd
== fd
) {
2431 __io_state_file_put(state
);
2433 state
->file
= fget_many(fd
, state
->ios_left
);
2439 state
->has_refs
= state
->ios_left
;
2443 static bool io_bdev_nowait(struct block_device
*bdev
)
2446 return !bdev
|| queue_is_mq(bdev_get_queue(bdev
));
2453 * If we tracked the file through the SCM inflight mechanism, we could support
2454 * any file. For now, just ensure that anything potentially problematic is done
2457 static bool io_file_supports_async(struct file
*file
, int rw
)
2459 umode_t mode
= file_inode(file
)->i_mode
;
2461 if (S_ISBLK(mode
)) {
2462 if (io_bdev_nowait(file
->f_inode
->i_bdev
))
2466 if (S_ISCHR(mode
) || S_ISSOCK(mode
))
2468 if (S_ISREG(mode
)) {
2469 if (io_bdev_nowait(file
->f_inode
->i_sb
->s_bdev
) &&
2470 file
->f_op
!= &io_uring_fops
)
2475 /* any ->read/write should understand O_NONBLOCK */
2476 if (file
->f_flags
& O_NONBLOCK
)
2479 if (!(file
->f_mode
& FMODE_NOWAIT
))
2483 return file
->f_op
->read_iter
!= NULL
;
2485 return file
->f_op
->write_iter
!= NULL
;
2488 static int io_prep_rw(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
2489 bool force_nonblock
)
2491 struct io_ring_ctx
*ctx
= req
->ctx
;
2492 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
2496 if (S_ISREG(file_inode(req
->file
)->i_mode
))
2497 req
->flags
|= REQ_F_ISREG
;
2499 kiocb
->ki_pos
= READ_ONCE(sqe
->off
);
2500 if (kiocb
->ki_pos
== -1 && !(req
->file
->f_mode
& FMODE_STREAM
)) {
2501 req
->flags
|= REQ_F_CUR_POS
;
2502 kiocb
->ki_pos
= req
->file
->f_pos
;
2504 kiocb
->ki_hint
= ki_hint_validate(file_write_hint(kiocb
->ki_filp
));
2505 kiocb
->ki_flags
= iocb_flags(kiocb
->ki_filp
);
2506 ret
= kiocb_set_rw_flags(kiocb
, READ_ONCE(sqe
->rw_flags
));
2510 ioprio
= READ_ONCE(sqe
->ioprio
);
2512 ret
= ioprio_check_cap(ioprio
);
2516 kiocb
->ki_ioprio
= ioprio
;
2518 kiocb
->ki_ioprio
= get_current_ioprio();
2520 /* don't allow async punt if RWF_NOWAIT was requested */
2521 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2522 req
->flags
|= REQ_F_NOWAIT
;
2524 if (kiocb
->ki_flags
& IOCB_DIRECT
)
2525 io_get_req_task(req
);
2528 kiocb
->ki_flags
|= IOCB_NOWAIT
;
2530 if (ctx
->flags
& IORING_SETUP_IOPOLL
) {
2531 if (!(kiocb
->ki_flags
& IOCB_DIRECT
) ||
2532 !kiocb
->ki_filp
->f_op
->iopoll
)
2535 kiocb
->ki_flags
|= IOCB_HIPRI
;
2536 kiocb
->ki_complete
= io_complete_rw_iopoll
;
2537 req
->iopoll_completed
= 0;
2538 io_get_req_task(req
);
2540 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2542 kiocb
->ki_complete
= io_complete_rw
;
2545 req
->rw
.addr
= READ_ONCE(sqe
->addr
);
2546 req
->rw
.len
= READ_ONCE(sqe
->len
);
2547 req
->buf_index
= READ_ONCE(sqe
->buf_index
);
2551 static inline void io_rw_done(struct kiocb
*kiocb
, ssize_t ret
)
2557 case -ERESTARTNOINTR
:
2558 case -ERESTARTNOHAND
:
2559 case -ERESTART_RESTARTBLOCK
:
2561 * We can't just restart the syscall, since previously
2562 * submitted sqes may already be in progress. Just fail this
2568 kiocb
->ki_complete(kiocb
, ret
, 0);
2572 static void kiocb_done(struct kiocb
*kiocb
, ssize_t ret
,
2573 struct io_comp_state
*cs
)
2575 struct io_kiocb
*req
= container_of(kiocb
, struct io_kiocb
, rw
.kiocb
);
2577 /* add previously done IO, if any */
2578 if (req
->io
&& req
->io
->rw
.bytes_done
> 0) {
2580 ret
= req
->io
->rw
.bytes_done
;
2582 ret
+= req
->io
->rw
.bytes_done
;
2585 if (req
->flags
& REQ_F_CUR_POS
)
2586 req
->file
->f_pos
= kiocb
->ki_pos
;
2587 if (ret
>= 0 && kiocb
->ki_complete
== io_complete_rw
)
2588 __io_complete_rw(req
, ret
, 0, cs
);
2590 io_rw_done(kiocb
, ret
);
2593 static ssize_t
io_import_fixed(struct io_kiocb
*req
, int rw
,
2594 struct iov_iter
*iter
)
2596 struct io_ring_ctx
*ctx
= req
->ctx
;
2597 size_t len
= req
->rw
.len
;
2598 struct io_mapped_ubuf
*imu
;
2599 u16 index
, buf_index
;
2603 /* attempt to use fixed buffers without having provided iovecs */
2604 if (unlikely(!ctx
->user_bufs
))
2607 buf_index
= req
->buf_index
;
2608 if (unlikely(buf_index
>= ctx
->nr_user_bufs
))
2611 index
= array_index_nospec(buf_index
, ctx
->nr_user_bufs
);
2612 imu
= &ctx
->user_bufs
[index
];
2613 buf_addr
= req
->rw
.addr
;
2616 if (buf_addr
+ len
< buf_addr
)
2618 /* not inside the mapped region */
2619 if (buf_addr
< imu
->ubuf
|| buf_addr
+ len
> imu
->ubuf
+ imu
->len
)
2623 * May not be a start of buffer, set size appropriately
2624 * and advance us to the beginning.
2626 offset
= buf_addr
- imu
->ubuf
;
2627 iov_iter_bvec(iter
, rw
, imu
->bvec
, imu
->nr_bvecs
, offset
+ len
);
2631 * Don't use iov_iter_advance() here, as it's really slow for
2632 * using the latter parts of a big fixed buffer - it iterates
2633 * over each segment manually. We can cheat a bit here, because
2636 * 1) it's a BVEC iter, we set it up
2637 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2638 * first and last bvec
2640 * So just find our index, and adjust the iterator afterwards.
2641 * If the offset is within the first bvec (or the whole first
2642 * bvec, just use iov_iter_advance(). This makes it easier
2643 * since we can just skip the first segment, which may not
2644 * be PAGE_SIZE aligned.
2646 const struct bio_vec
*bvec
= imu
->bvec
;
2648 if (offset
<= bvec
->bv_len
) {
2649 iov_iter_advance(iter
, offset
);
2651 unsigned long seg_skip
;
2653 /* skip first vec */
2654 offset
-= bvec
->bv_len
;
2655 seg_skip
= 1 + (offset
>> PAGE_SHIFT
);
2657 iter
->bvec
= bvec
+ seg_skip
;
2658 iter
->nr_segs
-= seg_skip
;
2659 iter
->count
-= bvec
->bv_len
+ offset
;
2660 iter
->iov_offset
= offset
& ~PAGE_MASK
;
2667 static void io_ring_submit_unlock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2670 mutex_unlock(&ctx
->uring_lock
);
2673 static void io_ring_submit_lock(struct io_ring_ctx
*ctx
, bool needs_lock
)
2676 * "Normal" inline submissions always hold the uring_lock, since we
2677 * grab it from the system call. Same is true for the SQPOLL offload.
2678 * The only exception is when we've detached the request and issue it
2679 * from an async worker thread, grab the lock for that case.
2682 mutex_lock(&ctx
->uring_lock
);
2685 static struct io_buffer
*io_buffer_select(struct io_kiocb
*req
, size_t *len
,
2686 int bgid
, struct io_buffer
*kbuf
,
2689 struct io_buffer
*head
;
2691 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
2694 io_ring_submit_lock(req
->ctx
, needs_lock
);
2696 lockdep_assert_held(&req
->ctx
->uring_lock
);
2698 head
= idr_find(&req
->ctx
->io_buffer_idr
, bgid
);
2700 if (!list_empty(&head
->list
)) {
2701 kbuf
= list_last_entry(&head
->list
, struct io_buffer
,
2703 list_del(&kbuf
->list
);
2706 idr_remove(&req
->ctx
->io_buffer_idr
, bgid
);
2708 if (*len
> kbuf
->len
)
2711 kbuf
= ERR_PTR(-ENOBUFS
);
2714 io_ring_submit_unlock(req
->ctx
, needs_lock
);
2719 static void __user
*io_rw_buffer_select(struct io_kiocb
*req
, size_t *len
,
2722 struct io_buffer
*kbuf
;
2725 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2726 bgid
= req
->buf_index
;
2727 kbuf
= io_buffer_select(req
, len
, bgid
, kbuf
, needs_lock
);
2730 req
->rw
.addr
= (u64
) (unsigned long) kbuf
;
2731 req
->flags
|= REQ_F_BUFFER_SELECTED
;
2732 return u64_to_user_ptr(kbuf
->addr
);
2735 #ifdef CONFIG_COMPAT
2736 static ssize_t
io_compat_import(struct io_kiocb
*req
, struct iovec
*iov
,
2739 struct compat_iovec __user
*uiov
;
2740 compat_ssize_t clen
;
2744 uiov
= u64_to_user_ptr(req
->rw
.addr
);
2745 if (!access_ok(uiov
, sizeof(*uiov
)))
2747 if (__get_user(clen
, &uiov
->iov_len
))
2753 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2755 return PTR_ERR(buf
);
2756 iov
[0].iov_base
= buf
;
2757 iov
[0].iov_len
= (compat_size_t
) len
;
2762 static ssize_t
__io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2765 struct iovec __user
*uiov
= u64_to_user_ptr(req
->rw
.addr
);
2769 if (copy_from_user(iov
, uiov
, sizeof(*uiov
)))
2772 len
= iov
[0].iov_len
;
2775 buf
= io_rw_buffer_select(req
, &len
, needs_lock
);
2777 return PTR_ERR(buf
);
2778 iov
[0].iov_base
= buf
;
2779 iov
[0].iov_len
= len
;
2783 static ssize_t
io_iov_buffer_select(struct io_kiocb
*req
, struct iovec
*iov
,
2786 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
2787 struct io_buffer
*kbuf
;
2789 kbuf
= (struct io_buffer
*) (unsigned long) req
->rw
.addr
;
2790 iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
2791 iov
[0].iov_len
= kbuf
->len
;
2796 else if (req
->rw
.len
> 1)
2799 #ifdef CONFIG_COMPAT
2800 if (req
->ctx
->compat
)
2801 return io_compat_import(req
, iov
, needs_lock
);
2804 return __io_iov_buffer_select(req
, iov
, needs_lock
);
2807 static ssize_t
__io_import_iovec(int rw
, struct io_kiocb
*req
,
2808 struct iovec
**iovec
, struct iov_iter
*iter
,
2811 void __user
*buf
= u64_to_user_ptr(req
->rw
.addr
);
2812 size_t sqe_len
= req
->rw
.len
;
2816 opcode
= req
->opcode
;
2817 if (opcode
== IORING_OP_READ_FIXED
|| opcode
== IORING_OP_WRITE_FIXED
) {
2819 return io_import_fixed(req
, rw
, iter
);
2822 /* buffer index only valid with fixed read/write, or buffer select */
2823 if (req
->buf_index
&& !(req
->flags
& REQ_F_BUFFER_SELECT
))
2826 if (opcode
== IORING_OP_READ
|| opcode
== IORING_OP_WRITE
) {
2827 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2828 buf
= io_rw_buffer_select(req
, &sqe_len
, needs_lock
);
2830 return PTR_ERR(buf
);
2831 req
->rw
.len
= sqe_len
;
2834 ret
= import_single_range(rw
, buf
, sqe_len
, *iovec
, iter
);
2836 return ret
< 0 ? ret
: sqe_len
;
2839 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
2840 ret
= io_iov_buffer_select(req
, *iovec
, needs_lock
);
2842 ret
= (*iovec
)->iov_len
;
2843 iov_iter_init(iter
, rw
, *iovec
, 1, ret
);
2849 #ifdef CONFIG_COMPAT
2850 if (req
->ctx
->compat
)
2851 return compat_import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
,
2855 return import_iovec(rw
, buf
, sqe_len
, UIO_FASTIOV
, iovec
, iter
);
2858 static ssize_t
io_import_iovec(int rw
, struct io_kiocb
*req
,
2859 struct iovec
**iovec
, struct iov_iter
*iter
,
2863 return __io_import_iovec(rw
, req
, iovec
, iter
, needs_lock
);
2865 return iov_iter_count(&req
->io
->rw
.iter
);
2869 * For files that don't have ->read_iter() and ->write_iter(), handle them
2870 * by looping over ->read() or ->write() manually.
2872 static ssize_t
loop_rw_iter(int rw
, struct file
*file
, struct kiocb
*kiocb
,
2873 struct iov_iter
*iter
)
2878 * Don't support polled IO through this interface, and we can't
2879 * support non-blocking either. For the latter, this just causes
2880 * the kiocb to be handled from an async context.
2882 if (kiocb
->ki_flags
& IOCB_HIPRI
)
2884 if (kiocb
->ki_flags
& IOCB_NOWAIT
)
2887 while (iov_iter_count(iter
)) {
2891 if (!iov_iter_is_bvec(iter
)) {
2892 iovec
= iov_iter_iovec(iter
);
2894 /* fixed buffers import bvec */
2895 iovec
.iov_base
= kmap(iter
->bvec
->bv_page
)
2897 iovec
.iov_len
= min(iter
->count
,
2898 iter
->bvec
->bv_len
- iter
->iov_offset
);
2902 nr
= file
->f_op
->read(file
, iovec
.iov_base
,
2903 iovec
.iov_len
, &kiocb
->ki_pos
);
2905 nr
= file
->f_op
->write(file
, iovec
.iov_base
,
2906 iovec
.iov_len
, &kiocb
->ki_pos
);
2909 if (iov_iter_is_bvec(iter
))
2910 kunmap(iter
->bvec
->bv_page
);
2918 if (nr
!= iovec
.iov_len
)
2920 iov_iter_advance(iter
, nr
);
2926 static void io_req_map_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
2927 const struct iovec
*fast_iov
, struct iov_iter
*iter
)
2929 struct io_async_rw
*rw
= &req
->io
->rw
;
2931 memcpy(&rw
->iter
, iter
, sizeof(*iter
));
2932 rw
->free_iovec
= NULL
;
2934 /* can only be fixed buffers, no need to do anything */
2935 if (iter
->type
== ITER_BVEC
)
2938 unsigned iov_off
= 0;
2940 rw
->iter
.iov
= rw
->fast_iov
;
2941 if (iter
->iov
!= fast_iov
) {
2942 iov_off
= iter
->iov
- fast_iov
;
2943 rw
->iter
.iov
+= iov_off
;
2945 if (rw
->fast_iov
!= fast_iov
)
2946 memcpy(rw
->fast_iov
+ iov_off
, fast_iov
+ iov_off
,
2947 sizeof(struct iovec
) * iter
->nr_segs
);
2949 rw
->free_iovec
= iovec
;
2950 req
->flags
|= REQ_F_NEED_CLEANUP
;
2954 static inline int __io_alloc_async_ctx(struct io_kiocb
*req
)
2956 req
->io
= kmalloc(sizeof(*req
->io
), GFP_KERNEL
);
2957 return req
->io
== NULL
;
2960 static int io_alloc_async_ctx(struct io_kiocb
*req
)
2962 if (!io_op_defs
[req
->opcode
].async_ctx
)
2965 return __io_alloc_async_ctx(req
);
2968 static int io_setup_async_rw(struct io_kiocb
*req
, const struct iovec
*iovec
,
2969 const struct iovec
*fast_iov
,
2970 struct iov_iter
*iter
, bool force
)
2972 if (!force
&& !io_op_defs
[req
->opcode
].async_ctx
)
2975 if (__io_alloc_async_ctx(req
))
2978 io_req_map_rw(req
, iovec
, fast_iov
, iter
);
2983 static inline int io_rw_prep_async(struct io_kiocb
*req
, int rw
,
2984 bool force_nonblock
)
2986 struct io_async_rw
*iorw
= &req
->io
->rw
;
2989 iorw
->iter
.iov
= iorw
->fast_iov
;
2990 ret
= __io_import_iovec(rw
, req
, (struct iovec
**) &iorw
->iter
.iov
,
2991 &iorw
->iter
, !force_nonblock
);
2992 if (unlikely(ret
< 0))
2995 io_req_map_rw(req
, iorw
->iter
.iov
, iorw
->fast_iov
, &iorw
->iter
);
2999 static int io_read_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
3000 bool force_nonblock
)
3004 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
3008 if (unlikely(!(req
->file
->f_mode
& FMODE_READ
)))
3011 /* either don't need iovec imported or already have it */
3012 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
3014 return io_rw_prep_async(req
, READ
, force_nonblock
);
3018 * This is our waitqueue callback handler, registered through lock_page_async()
3019 * when we initially tried to do the IO with the iocb armed our waitqueue.
3020 * This gets called when the page is unlocked, and we generally expect that to
3021 * happen when the page IO is completed and the page is now uptodate. This will
3022 * queue a task_work based retry of the operation, attempting to copy the data
3023 * again. If the latter fails because the page was NOT uptodate, then we will
3024 * do a thread based blocking retry of the operation. That's the unexpected
3027 static int io_async_buf_func(struct wait_queue_entry
*wait
, unsigned mode
,
3028 int sync
, void *arg
)
3030 struct wait_page_queue
*wpq
;
3031 struct io_kiocb
*req
= wait
->private;
3032 struct wait_page_key
*key
= arg
;
3035 wpq
= container_of(wait
, struct wait_page_queue
, wait
);
3037 if (!wake_page_match(wpq
, key
))
3040 list_del_init(&wait
->entry
);
3042 init_task_work(&req
->task_work
, io_req_task_submit
);
3043 percpu_ref_get(&req
->ctx
->refs
);
3045 /* submit ref gets dropped, acquire a new one */
3046 refcount_inc(&req
->refs
);
3047 ret
= io_req_task_work_add(req
, &req
->task_work
);
3048 if (unlikely(ret
)) {
3049 struct task_struct
*tsk
;
3051 /* queue just for cancelation */
3052 init_task_work(&req
->task_work
, io_req_task_cancel
);
3053 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
3054 task_work_add(tsk
, &req
->task_work
, 0);
3055 wake_up_process(tsk
);
3061 * This controls whether a given IO request should be armed for async page
3062 * based retry. If we return false here, the request is handed to the async
3063 * worker threads for retry. If we're doing buffered reads on a regular file,
3064 * we prepare a private wait_page_queue entry and retry the operation. This
3065 * will either succeed because the page is now uptodate and unlocked, or it
3066 * will register a callback when the page is unlocked at IO completion. Through
3067 * that callback, io_uring uses task_work to setup a retry of the operation.
3068 * That retry will attempt the buffered read again. The retry will generally
3069 * succeed, or in rare cases where it fails, we then fall back to using the
3070 * async worker threads for a blocking retry.
3072 static bool io_rw_should_retry(struct io_kiocb
*req
)
3074 struct wait_page_queue
*wait
= &req
->io
->rw
.wpq
;
3075 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3077 /* never retry for NOWAIT, we just complete with -EAGAIN */
3078 if (req
->flags
& REQ_F_NOWAIT
)
3081 /* Only for buffered IO */
3082 if (kiocb
->ki_flags
& (IOCB_DIRECT
| IOCB_HIPRI
))
3086 * just use poll if we can, and don't attempt if the fs doesn't
3087 * support callback based unlocks
3089 if (file_can_poll(req
->file
) || !(req
->file
->f_mode
& FMODE_BUF_RASYNC
))
3092 wait
->wait
.func
= io_async_buf_func
;
3093 wait
->wait
.private = req
;
3094 wait
->wait
.flags
= 0;
3095 INIT_LIST_HEAD(&wait
->wait
.entry
);
3096 kiocb
->ki_flags
|= IOCB_WAITQ
;
3097 kiocb
->ki_waitq
= wait
;
3099 io_get_req_task(req
);
3103 static int io_iter_do_read(struct io_kiocb
*req
, struct iov_iter
*iter
)
3105 if (req
->file
->f_op
->read_iter
)
3106 return call_read_iter(req
->file
, &req
->rw
.kiocb
, iter
);
3107 else if (req
->file
->f_op
->read
)
3108 return loop_rw_iter(READ
, req
->file
, &req
->rw
.kiocb
, iter
);
3113 static int io_read(struct io_kiocb
*req
, bool force_nonblock
,
3114 struct io_comp_state
*cs
)
3116 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3117 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3118 struct iov_iter __iter
, *iter
= &__iter
;
3119 ssize_t io_size
, ret
, ret2
;
3123 iter
= &req
->io
->rw
.iter
;
3125 ret
= io_import_iovec(READ
, req
, &iovec
, iter
, !force_nonblock
);
3129 req
->result
= io_size
;
3132 /* Ensure we clear previously set non-block flag */
3133 if (!force_nonblock
)
3134 kiocb
->ki_flags
&= ~IOCB_NOWAIT
;
3136 /* If the file doesn't support async, just async punt */
3137 if (force_nonblock
&& !io_file_supports_async(req
->file
, READ
))
3140 iov_count
= iov_iter_count(iter
);
3141 ret
= rw_verify_area(READ
, req
->file
, &kiocb
->ki_pos
, iov_count
);
3145 ret
= io_iter_do_read(req
, iter
);
3149 } else if (ret
== -EIOCBQUEUED
) {
3152 } else if (ret
== -EAGAIN
) {
3153 if (!force_nonblock
)
3155 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3159 } else if (ret
< 0) {
3163 /* read it all, or we did blocking attempt. no retry. */
3164 if (!iov_iter_count(iter
) || !force_nonblock
||
3165 (req
->file
->f_flags
& O_NONBLOCK
))
3170 ret2
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, true);
3175 /* it's copied and will be cleaned with ->io */
3177 /* now use our persistent iterator, if we aren't already */
3178 iter
= &req
->io
->rw
.iter
;
3180 req
->io
->rw
.bytes_done
+= ret
;
3181 /* if we can retry, do so with the callbacks armed */
3182 if (!io_rw_should_retry(req
)) {
3183 kiocb
->ki_flags
&= ~IOCB_WAITQ
;
3188 * Now retry read with the IOCB_WAITQ parts set in the iocb. If we
3189 * get -EIOCBQUEUED, then we'll get a notification when the desired
3190 * page gets unlocked. We can also get a partial read here, and if we
3191 * do, then just retry at the new offset.
3193 ret
= io_iter_do_read(req
, iter
);
3194 if (ret
== -EIOCBQUEUED
) {
3197 } else if (ret
> 0 && ret
< io_size
) {
3198 /* we got some bytes, but not all. retry. */
3202 kiocb_done(kiocb
, ret
, cs
);
3205 /* it's reportedly faster than delegating the null check to kfree() */
3211 static int io_write_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
3212 bool force_nonblock
)
3216 ret
= io_prep_rw(req
, sqe
, force_nonblock
);
3220 if (unlikely(!(req
->file
->f_mode
& FMODE_WRITE
)))
3223 /* either don't need iovec imported or already have it */
3224 if (!req
->io
|| req
->flags
& REQ_F_NEED_CLEANUP
)
3226 return io_rw_prep_async(req
, WRITE
, force_nonblock
);
3229 static int io_write(struct io_kiocb
*req
, bool force_nonblock
,
3230 struct io_comp_state
*cs
)
3232 struct iovec inline_vecs
[UIO_FASTIOV
], *iovec
= inline_vecs
;
3233 struct kiocb
*kiocb
= &req
->rw
.kiocb
;
3234 struct iov_iter __iter
, *iter
= &__iter
;
3236 ssize_t ret
, ret2
, io_size
;
3239 iter
= &req
->io
->rw
.iter
;
3241 ret
= io_import_iovec(WRITE
, req
, &iovec
, iter
, !force_nonblock
);
3245 req
->result
= io_size
;
3247 /* Ensure we clear previously set non-block flag */
3248 if (!force_nonblock
)
3249 req
->rw
.kiocb
.ki_flags
&= ~IOCB_NOWAIT
;
3251 /* If the file doesn't support async, just async punt */
3252 if (force_nonblock
&& !io_file_supports_async(req
->file
, WRITE
))
3255 /* file path doesn't support NOWAIT for non-direct_IO */
3256 if (force_nonblock
&& !(kiocb
->ki_flags
& IOCB_DIRECT
) &&
3257 (req
->flags
& REQ_F_ISREG
))
3260 iov_count
= iov_iter_count(iter
);
3261 ret
= rw_verify_area(WRITE
, req
->file
, &kiocb
->ki_pos
, iov_count
);
3266 * Open-code file_start_write here to grab freeze protection,
3267 * which will be released by another thread in
3268 * io_complete_rw(). Fool lockdep by telling it the lock got
3269 * released so that it doesn't complain about the held lock when
3270 * we return to userspace.
3272 if (req
->flags
& REQ_F_ISREG
) {
3273 __sb_start_write(file_inode(req
->file
)->i_sb
,
3274 SB_FREEZE_WRITE
, true);
3275 __sb_writers_release(file_inode(req
->file
)->i_sb
,
3278 kiocb
->ki_flags
|= IOCB_WRITE
;
3280 if (req
->file
->f_op
->write_iter
)
3281 ret2
= call_write_iter(req
->file
, kiocb
, iter
);
3282 else if (req
->file
->f_op
->write
)
3283 ret2
= loop_rw_iter(WRITE
, req
->file
, kiocb
, iter
);
3288 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3289 * retry them without IOCB_NOWAIT.
3291 if (ret2
== -EOPNOTSUPP
&& (kiocb
->ki_flags
& IOCB_NOWAIT
))
3293 if (!force_nonblock
|| ret2
!= -EAGAIN
) {
3294 kiocb_done(kiocb
, ret2
, cs
);
3297 ret
= io_setup_async_rw(req
, iovec
, inline_vecs
, iter
, false);
3302 /* it's reportedly faster than delegating the null check to kfree() */
3308 static int __io_splice_prep(struct io_kiocb
*req
,
3309 const struct io_uring_sqe
*sqe
)
3311 struct io_splice
* sp
= &req
->splice
;
3312 unsigned int valid_flags
= SPLICE_F_FD_IN_FIXED
| SPLICE_F_ALL
;
3315 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3317 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3321 sp
->len
= READ_ONCE(sqe
->len
);
3322 sp
->flags
= READ_ONCE(sqe
->splice_flags
);
3324 if (unlikely(sp
->flags
& ~valid_flags
))
3327 ret
= io_file_get(NULL
, req
, READ_ONCE(sqe
->splice_fd_in
), &sp
->file_in
,
3328 (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3331 req
->flags
|= REQ_F_NEED_CLEANUP
;
3333 if (!S_ISREG(file_inode(sp
->file_in
)->i_mode
)) {
3335 * Splice operation will be punted aync, and here need to
3336 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3338 io_req_init_async(req
);
3339 req
->work
.flags
|= IO_WQ_WORK_UNBOUND
;
3345 static int io_tee_prep(struct io_kiocb
*req
,
3346 const struct io_uring_sqe
*sqe
)
3348 if (READ_ONCE(sqe
->splice_off_in
) || READ_ONCE(sqe
->off
))
3350 return __io_splice_prep(req
, sqe
);
3353 static int io_tee(struct io_kiocb
*req
, bool force_nonblock
)
3355 struct io_splice
*sp
= &req
->splice
;
3356 struct file
*in
= sp
->file_in
;
3357 struct file
*out
= sp
->file_out
;
3358 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3364 ret
= do_tee(in
, out
, sp
->len
, flags
);
3366 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3367 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3370 req_set_fail_links(req
);
3371 io_req_complete(req
, ret
);
3375 static int io_splice_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3377 struct io_splice
* sp
= &req
->splice
;
3379 sp
->off_in
= READ_ONCE(sqe
->splice_off_in
);
3380 sp
->off_out
= READ_ONCE(sqe
->off
);
3381 return __io_splice_prep(req
, sqe
);
3384 static int io_splice(struct io_kiocb
*req
, bool force_nonblock
)
3386 struct io_splice
*sp
= &req
->splice
;
3387 struct file
*in
= sp
->file_in
;
3388 struct file
*out
= sp
->file_out
;
3389 unsigned int flags
= sp
->flags
& ~SPLICE_F_FD_IN_FIXED
;
3390 loff_t
*poff_in
, *poff_out
;
3396 poff_in
= (sp
->off_in
== -1) ? NULL
: &sp
->off_in
;
3397 poff_out
= (sp
->off_out
== -1) ? NULL
: &sp
->off_out
;
3400 ret
= do_splice(in
, poff_in
, out
, poff_out
, sp
->len
, flags
);
3402 io_put_file(req
, in
, (sp
->flags
& SPLICE_F_FD_IN_FIXED
));
3403 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3406 req_set_fail_links(req
);
3407 io_req_complete(req
, ret
);
3412 * IORING_OP_NOP just posts a completion event, nothing else.
3414 static int io_nop(struct io_kiocb
*req
, struct io_comp_state
*cs
)
3416 struct io_ring_ctx
*ctx
= req
->ctx
;
3418 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3421 __io_req_complete(req
, 0, 0, cs
);
3425 static int io_prep_fsync(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3427 struct io_ring_ctx
*ctx
= req
->ctx
;
3432 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3434 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3437 req
->sync
.flags
= READ_ONCE(sqe
->fsync_flags
);
3438 if (unlikely(req
->sync
.flags
& ~IORING_FSYNC_DATASYNC
))
3441 req
->sync
.off
= READ_ONCE(sqe
->off
);
3442 req
->sync
.len
= READ_ONCE(sqe
->len
);
3446 static int io_fsync(struct io_kiocb
*req
, bool force_nonblock
)
3448 loff_t end
= req
->sync
.off
+ req
->sync
.len
;
3451 /* fsync always requires a blocking context */
3455 ret
= vfs_fsync_range(req
->file
, req
->sync
.off
,
3456 end
> 0 ? end
: LLONG_MAX
,
3457 req
->sync
.flags
& IORING_FSYNC_DATASYNC
);
3459 req_set_fail_links(req
);
3460 io_req_complete(req
, ret
);
3464 static int io_fallocate_prep(struct io_kiocb
*req
,
3465 const struct io_uring_sqe
*sqe
)
3467 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->rw_flags
)
3469 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3472 req
->sync
.off
= READ_ONCE(sqe
->off
);
3473 req
->sync
.len
= READ_ONCE(sqe
->addr
);
3474 req
->sync
.mode
= READ_ONCE(sqe
->len
);
3478 static int io_fallocate(struct io_kiocb
*req
, bool force_nonblock
)
3482 /* fallocate always requiring blocking context */
3485 ret
= vfs_fallocate(req
->file
, req
->sync
.mode
, req
->sync
.off
,
3488 req_set_fail_links(req
);
3489 io_req_complete(req
, ret
);
3493 static int __io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3495 const char __user
*fname
;
3498 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3500 if (unlikely(sqe
->ioprio
|| sqe
->buf_index
))
3502 if (unlikely(req
->flags
& REQ_F_FIXED_FILE
))
3505 /* open.how should be already initialised */
3506 if (!(req
->open
.how
.flags
& O_PATH
) && force_o_largefile())
3507 req
->open
.how
.flags
|= O_LARGEFILE
;
3509 req
->open
.dfd
= READ_ONCE(sqe
->fd
);
3510 fname
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3511 req
->open
.filename
= getname(fname
);
3512 if (IS_ERR(req
->open
.filename
)) {
3513 ret
= PTR_ERR(req
->open
.filename
);
3514 req
->open
.filename
= NULL
;
3517 req
->open
.nofile
= rlimit(RLIMIT_NOFILE
);
3518 req
->flags
|= REQ_F_NEED_CLEANUP
;
3522 static int io_openat_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3526 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3528 mode
= READ_ONCE(sqe
->len
);
3529 flags
= READ_ONCE(sqe
->open_flags
);
3530 req
->open
.how
= build_open_how(flags
, mode
);
3531 return __io_openat_prep(req
, sqe
);
3534 static int io_openat2_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3536 struct open_how __user
*how
;
3540 if (req
->flags
& REQ_F_NEED_CLEANUP
)
3542 how
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3543 len
= READ_ONCE(sqe
->len
);
3544 if (len
< OPEN_HOW_SIZE_VER0
)
3547 ret
= copy_struct_from_user(&req
->open
.how
, sizeof(req
->open
.how
), how
,
3552 return __io_openat_prep(req
, sqe
);
3555 static int io_openat2(struct io_kiocb
*req
, bool force_nonblock
)
3557 struct open_flags op
;
3564 ret
= build_open_flags(&req
->open
.how
, &op
);
3568 ret
= __get_unused_fd_flags(req
->open
.how
.flags
, req
->open
.nofile
);
3572 file
= do_filp_open(req
->open
.dfd
, req
->open
.filename
, &op
);
3575 ret
= PTR_ERR(file
);
3577 fsnotify_open(file
);
3578 fd_install(ret
, file
);
3581 putname(req
->open
.filename
);
3582 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
3584 req_set_fail_links(req
);
3585 io_req_complete(req
, ret
);
3589 static int io_openat(struct io_kiocb
*req
, bool force_nonblock
)
3591 return io_openat2(req
, force_nonblock
);
3594 static int io_remove_buffers_prep(struct io_kiocb
*req
,
3595 const struct io_uring_sqe
*sqe
)
3597 struct io_provide_buf
*p
= &req
->pbuf
;
3600 if (sqe
->ioprio
|| sqe
->rw_flags
|| sqe
->addr
|| sqe
->len
|| sqe
->off
)
3603 tmp
= READ_ONCE(sqe
->fd
);
3604 if (!tmp
|| tmp
> USHRT_MAX
)
3607 memset(p
, 0, sizeof(*p
));
3609 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3613 static int __io_remove_buffers(struct io_ring_ctx
*ctx
, struct io_buffer
*buf
,
3614 int bgid
, unsigned nbufs
)
3618 /* shouldn't happen */
3622 /* the head kbuf is the list itself */
3623 while (!list_empty(&buf
->list
)) {
3624 struct io_buffer
*nxt
;
3626 nxt
= list_first_entry(&buf
->list
, struct io_buffer
, list
);
3627 list_del(&nxt
->list
);
3634 idr_remove(&ctx
->io_buffer_idr
, bgid
);
3639 static int io_remove_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3640 struct io_comp_state
*cs
)
3642 struct io_provide_buf
*p
= &req
->pbuf
;
3643 struct io_ring_ctx
*ctx
= req
->ctx
;
3644 struct io_buffer
*head
;
3647 io_ring_submit_lock(ctx
, !force_nonblock
);
3649 lockdep_assert_held(&ctx
->uring_lock
);
3652 head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3654 ret
= __io_remove_buffers(ctx
, head
, p
->bgid
, p
->nbufs
);
3656 io_ring_submit_lock(ctx
, !force_nonblock
);
3658 req_set_fail_links(req
);
3659 __io_req_complete(req
, ret
, 0, cs
);
3663 static int io_provide_buffers_prep(struct io_kiocb
*req
,
3664 const struct io_uring_sqe
*sqe
)
3666 struct io_provide_buf
*p
= &req
->pbuf
;
3669 if (sqe
->ioprio
|| sqe
->rw_flags
)
3672 tmp
= READ_ONCE(sqe
->fd
);
3673 if (!tmp
|| tmp
> USHRT_MAX
)
3676 p
->addr
= READ_ONCE(sqe
->addr
);
3677 p
->len
= READ_ONCE(sqe
->len
);
3679 if (!access_ok(u64_to_user_ptr(p
->addr
), (p
->len
* p
->nbufs
)))
3682 p
->bgid
= READ_ONCE(sqe
->buf_group
);
3683 tmp
= READ_ONCE(sqe
->off
);
3684 if (tmp
> USHRT_MAX
)
3690 static int io_add_buffers(struct io_provide_buf
*pbuf
, struct io_buffer
**head
)
3692 struct io_buffer
*buf
;
3693 u64 addr
= pbuf
->addr
;
3694 int i
, bid
= pbuf
->bid
;
3696 for (i
= 0; i
< pbuf
->nbufs
; i
++) {
3697 buf
= kmalloc(sizeof(*buf
), GFP_KERNEL
);
3702 buf
->len
= pbuf
->len
;
3707 INIT_LIST_HEAD(&buf
->list
);
3710 list_add_tail(&buf
->list
, &(*head
)->list
);
3714 return i
? i
: -ENOMEM
;
3717 static int io_provide_buffers(struct io_kiocb
*req
, bool force_nonblock
,
3718 struct io_comp_state
*cs
)
3720 struct io_provide_buf
*p
= &req
->pbuf
;
3721 struct io_ring_ctx
*ctx
= req
->ctx
;
3722 struct io_buffer
*head
, *list
;
3725 io_ring_submit_lock(ctx
, !force_nonblock
);
3727 lockdep_assert_held(&ctx
->uring_lock
);
3729 list
= head
= idr_find(&ctx
->io_buffer_idr
, p
->bgid
);
3731 ret
= io_add_buffers(p
, &head
);
3736 ret
= idr_alloc(&ctx
->io_buffer_idr
, head
, p
->bgid
, p
->bgid
+ 1,
3739 __io_remove_buffers(ctx
, head
, p
->bgid
, -1U);
3744 io_ring_submit_unlock(ctx
, !force_nonblock
);
3746 req_set_fail_links(req
);
3747 __io_req_complete(req
, ret
, 0, cs
);
3751 static int io_epoll_ctl_prep(struct io_kiocb
*req
,
3752 const struct io_uring_sqe
*sqe
)
3754 #if defined(CONFIG_EPOLL)
3755 if (sqe
->ioprio
|| sqe
->buf_index
)
3757 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3760 req
->epoll
.epfd
= READ_ONCE(sqe
->fd
);
3761 req
->epoll
.op
= READ_ONCE(sqe
->len
);
3762 req
->epoll
.fd
= READ_ONCE(sqe
->off
);
3764 if (ep_op_has_event(req
->epoll
.op
)) {
3765 struct epoll_event __user
*ev
;
3767 ev
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3768 if (copy_from_user(&req
->epoll
.event
, ev
, sizeof(*ev
)))
3778 static int io_epoll_ctl(struct io_kiocb
*req
, bool force_nonblock
,
3779 struct io_comp_state
*cs
)
3781 #if defined(CONFIG_EPOLL)
3782 struct io_epoll
*ie
= &req
->epoll
;
3785 ret
= do_epoll_ctl(ie
->epfd
, ie
->op
, ie
->fd
, &ie
->event
, force_nonblock
);
3786 if (force_nonblock
&& ret
== -EAGAIN
)
3790 req_set_fail_links(req
);
3791 __io_req_complete(req
, ret
, 0, cs
);
3798 static int io_madvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3800 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3801 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->off
)
3803 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3806 req
->madvise
.addr
= READ_ONCE(sqe
->addr
);
3807 req
->madvise
.len
= READ_ONCE(sqe
->len
);
3808 req
->madvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3815 static int io_madvise(struct io_kiocb
*req
, bool force_nonblock
)
3817 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
3818 struct io_madvise
*ma
= &req
->madvise
;
3824 ret
= do_madvise(ma
->addr
, ma
->len
, ma
->advice
);
3826 req_set_fail_links(req
);
3827 io_req_complete(req
, ret
);
3834 static int io_fadvise_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3836 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->addr
)
3838 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3841 req
->fadvise
.offset
= READ_ONCE(sqe
->off
);
3842 req
->fadvise
.len
= READ_ONCE(sqe
->len
);
3843 req
->fadvise
.advice
= READ_ONCE(sqe
->fadvise_advice
);
3847 static int io_fadvise(struct io_kiocb
*req
, bool force_nonblock
)
3849 struct io_fadvise
*fa
= &req
->fadvise
;
3852 if (force_nonblock
) {
3853 switch (fa
->advice
) {
3854 case POSIX_FADV_NORMAL
:
3855 case POSIX_FADV_RANDOM
:
3856 case POSIX_FADV_SEQUENTIAL
:
3863 ret
= vfs_fadvise(req
->file
, fa
->offset
, fa
->len
, fa
->advice
);
3865 req_set_fail_links(req
);
3866 io_req_complete(req
, ret
);
3870 static int io_statx_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3872 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
3874 if (sqe
->ioprio
|| sqe
->buf_index
)
3876 if (req
->flags
& REQ_F_FIXED_FILE
)
3879 req
->statx
.dfd
= READ_ONCE(sqe
->fd
);
3880 req
->statx
.mask
= READ_ONCE(sqe
->len
);
3881 req
->statx
.filename
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
3882 req
->statx
.buffer
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
3883 req
->statx
.flags
= READ_ONCE(sqe
->statx_flags
);
3888 static int io_statx(struct io_kiocb
*req
, bool force_nonblock
)
3890 struct io_statx
*ctx
= &req
->statx
;
3893 if (force_nonblock
) {
3894 /* only need file table for an actual valid fd */
3895 if (ctx
->dfd
== -1 || ctx
->dfd
== AT_FDCWD
)
3896 req
->flags
|= REQ_F_NO_FILE_TABLE
;
3900 ret
= do_statx(ctx
->dfd
, ctx
->filename
, ctx
->flags
, ctx
->mask
,
3904 req_set_fail_links(req
);
3905 io_req_complete(req
, ret
);
3909 static int io_close_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3912 * If we queue this for async, it must not be cancellable. That would
3913 * leave the 'file' in an undeterminate state, and here need to modify
3914 * io_wq_work.flags, so initialize io_wq_work firstly.
3916 io_req_init_async(req
);
3917 req
->work
.flags
|= IO_WQ_WORK_NO_CANCEL
;
3919 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
3921 if (sqe
->ioprio
|| sqe
->off
|| sqe
->addr
|| sqe
->len
||
3922 sqe
->rw_flags
|| sqe
->buf_index
)
3924 if (req
->flags
& REQ_F_FIXED_FILE
)
3927 req
->close
.fd
= READ_ONCE(sqe
->fd
);
3928 if ((req
->file
&& req
->file
->f_op
== &io_uring_fops
) ||
3929 req
->close
.fd
== req
->ctx
->ring_fd
)
3932 req
->close
.put_file
= NULL
;
3936 static int io_close(struct io_kiocb
*req
, bool force_nonblock
,
3937 struct io_comp_state
*cs
)
3939 struct io_close
*close
= &req
->close
;
3942 /* might be already done during nonblock submission */
3943 if (!close
->put_file
) {
3944 ret
= __close_fd_get_file(close
->fd
, &close
->put_file
);
3946 return (ret
== -ENOENT
) ? -EBADF
: ret
;
3949 /* if the file has a flush method, be safe and punt to async */
3950 if (close
->put_file
->f_op
->flush
&& force_nonblock
) {
3951 /* was never set, but play safe */
3952 req
->flags
&= ~REQ_F_NOWAIT
;
3953 /* avoid grabbing files - we don't need the files */
3954 req
->flags
|= REQ_F_NO_FILE_TABLE
;
3958 /* No ->flush() or already async, safely close from here */
3959 ret
= filp_close(close
->put_file
, req
->work
.files
);
3961 req_set_fail_links(req
);
3962 fput(close
->put_file
);
3963 close
->put_file
= NULL
;
3964 __io_req_complete(req
, ret
, 0, cs
);
3968 static int io_prep_sfr(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
3970 struct io_ring_ctx
*ctx
= req
->ctx
;
3975 if (unlikely(ctx
->flags
& IORING_SETUP_IOPOLL
))
3977 if (unlikely(sqe
->addr
|| sqe
->ioprio
|| sqe
->buf_index
))
3980 req
->sync
.off
= READ_ONCE(sqe
->off
);
3981 req
->sync
.len
= READ_ONCE(sqe
->len
);
3982 req
->sync
.flags
= READ_ONCE(sqe
->sync_range_flags
);
3986 static int io_sync_file_range(struct io_kiocb
*req
, bool force_nonblock
)
3990 /* sync_file_range always requires a blocking context */
3994 ret
= sync_file_range(req
->file
, req
->sync
.off
, req
->sync
.len
,
3997 req_set_fail_links(req
);
3998 io_req_complete(req
, ret
);
4002 #if defined(CONFIG_NET)
4003 static int io_setup_async_msg(struct io_kiocb
*req
,
4004 struct io_async_msghdr
*kmsg
)
4008 if (io_alloc_async_ctx(req
)) {
4009 if (kmsg
->iov
!= kmsg
->fast_iov
)
4013 req
->flags
|= REQ_F_NEED_CLEANUP
;
4014 memcpy(&req
->io
->msg
, kmsg
, sizeof(*kmsg
));
4018 static int io_sendmsg_copy_hdr(struct io_kiocb
*req
,
4019 struct io_async_msghdr
*iomsg
)
4021 iomsg
->iov
= iomsg
->fast_iov
;
4022 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4023 return sendmsg_copy_msghdr(&iomsg
->msg
, req
->sr_msg
.umsg
,
4024 req
->sr_msg
.msg_flags
, &iomsg
->iov
);
4027 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4029 struct io_sr_msg
*sr
= &req
->sr_msg
;
4030 struct io_async_ctx
*io
= req
->io
;
4033 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4036 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4037 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4038 sr
->len
= READ_ONCE(sqe
->len
);
4040 #ifdef CONFIG_COMPAT
4041 if (req
->ctx
->compat
)
4042 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4045 if (!io
|| req
->opcode
== IORING_OP_SEND
)
4047 /* iovec is already imported */
4048 if (req
->flags
& REQ_F_NEED_CLEANUP
)
4051 ret
= io_sendmsg_copy_hdr(req
, &io
->msg
);
4053 req
->flags
|= REQ_F_NEED_CLEANUP
;
4057 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4058 struct io_comp_state
*cs
)
4060 struct io_async_msghdr iomsg
, *kmsg
;
4061 struct socket
*sock
;
4065 sock
= sock_from_file(req
->file
, &ret
);
4066 if (unlikely(!sock
))
4070 kmsg
= &req
->io
->msg
;
4071 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
4072 /* if iov is set, it's allocated already */
4074 kmsg
->iov
= kmsg
->fast_iov
;
4075 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4077 ret
= io_sendmsg_copy_hdr(req
, &iomsg
);
4083 flags
= req
->sr_msg
.msg_flags
;
4084 if (flags
& MSG_DONTWAIT
)
4085 req
->flags
|= REQ_F_NOWAIT
;
4086 else if (force_nonblock
)
4087 flags
|= MSG_DONTWAIT
;
4089 ret
= __sys_sendmsg_sock(sock
, &kmsg
->msg
, flags
);
4090 if (force_nonblock
&& ret
== -EAGAIN
)
4091 return io_setup_async_msg(req
, kmsg
);
4092 if (ret
== -ERESTARTSYS
)
4095 if (kmsg
->iov
!= kmsg
->fast_iov
)
4097 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4099 req_set_fail_links(req
);
4100 __io_req_complete(req
, ret
, 0, cs
);
4104 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4105 struct io_comp_state
*cs
)
4107 struct io_sr_msg
*sr
= &req
->sr_msg
;
4110 struct socket
*sock
;
4114 sock
= sock_from_file(req
->file
, &ret
);
4115 if (unlikely(!sock
))
4118 ret
= import_single_range(WRITE
, sr
->buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4122 msg
.msg_name
= NULL
;
4123 msg
.msg_control
= NULL
;
4124 msg
.msg_controllen
= 0;
4125 msg
.msg_namelen
= 0;
4127 flags
= req
->sr_msg
.msg_flags
;
4128 if (flags
& MSG_DONTWAIT
)
4129 req
->flags
|= REQ_F_NOWAIT
;
4130 else if (force_nonblock
)
4131 flags
|= MSG_DONTWAIT
;
4133 msg
.msg_flags
= flags
;
4134 ret
= sock_sendmsg(sock
, &msg
);
4135 if (force_nonblock
&& ret
== -EAGAIN
)
4137 if (ret
== -ERESTARTSYS
)
4141 req_set_fail_links(req
);
4142 __io_req_complete(req
, ret
, 0, cs
);
4146 static int __io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4147 struct io_async_msghdr
*iomsg
)
4149 struct io_sr_msg
*sr
= &req
->sr_msg
;
4150 struct iovec __user
*uiov
;
4154 ret
= __copy_msghdr_from_user(&iomsg
->msg
, sr
->umsg
,
4155 &iomsg
->uaddr
, &uiov
, &iov_len
);
4159 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4162 if (copy_from_user(iomsg
->iov
, uiov
, sizeof(*uiov
)))
4164 sr
->len
= iomsg
->iov
[0].iov_len
;
4165 iov_iter_init(&iomsg
->msg
.msg_iter
, READ
, iomsg
->iov
, 1,
4169 ret
= import_iovec(READ
, uiov
, iov_len
, UIO_FASTIOV
,
4170 &iomsg
->iov
, &iomsg
->msg
.msg_iter
);
4178 #ifdef CONFIG_COMPAT
4179 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb
*req
,
4180 struct io_async_msghdr
*iomsg
)
4182 struct compat_msghdr __user
*msg_compat
;
4183 struct io_sr_msg
*sr
= &req
->sr_msg
;
4184 struct compat_iovec __user
*uiov
;
4189 msg_compat
= (struct compat_msghdr __user
*) sr
->umsg
;
4190 ret
= __get_compat_msghdr(&iomsg
->msg
, msg_compat
, &iomsg
->uaddr
,
4195 uiov
= compat_ptr(ptr
);
4196 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4197 compat_ssize_t clen
;
4201 if (!access_ok(uiov
, sizeof(*uiov
)))
4203 if (__get_user(clen
, &uiov
->iov_len
))
4207 sr
->len
= iomsg
->iov
[0].iov_len
;
4210 ret
= compat_import_iovec(READ
, uiov
, len
, UIO_FASTIOV
,
4212 &iomsg
->msg
.msg_iter
);
4221 static int io_recvmsg_copy_hdr(struct io_kiocb
*req
,
4222 struct io_async_msghdr
*iomsg
)
4224 iomsg
->msg
.msg_name
= &iomsg
->addr
;
4225 iomsg
->iov
= iomsg
->fast_iov
;
4227 #ifdef CONFIG_COMPAT
4228 if (req
->ctx
->compat
)
4229 return __io_compat_recvmsg_copy_hdr(req
, iomsg
);
4232 return __io_recvmsg_copy_hdr(req
, iomsg
);
4235 static struct io_buffer
*io_recv_buffer_select(struct io_kiocb
*req
,
4238 struct io_sr_msg
*sr
= &req
->sr_msg
;
4239 struct io_buffer
*kbuf
;
4241 kbuf
= io_buffer_select(req
, &sr
->len
, sr
->bgid
, sr
->kbuf
, needs_lock
);
4246 req
->flags
|= REQ_F_BUFFER_SELECTED
;
4250 static inline unsigned int io_put_recv_kbuf(struct io_kiocb
*req
)
4252 return io_put_kbuf(req
, req
->sr_msg
.kbuf
);
4255 static int io_recvmsg_prep(struct io_kiocb
*req
,
4256 const struct io_uring_sqe
*sqe
)
4258 struct io_sr_msg
*sr
= &req
->sr_msg
;
4259 struct io_async_ctx
*io
= req
->io
;
4262 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
4265 sr
->msg_flags
= READ_ONCE(sqe
->msg_flags
);
4266 sr
->umsg
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4267 sr
->len
= READ_ONCE(sqe
->len
);
4268 sr
->bgid
= READ_ONCE(sqe
->buf_group
);
4270 #ifdef CONFIG_COMPAT
4271 if (req
->ctx
->compat
)
4272 sr
->msg_flags
|= MSG_CMSG_COMPAT
;
4275 if (!io
|| req
->opcode
== IORING_OP_RECV
)
4277 /* iovec is already imported */
4278 if (req
->flags
& REQ_F_NEED_CLEANUP
)
4281 ret
= io_recvmsg_copy_hdr(req
, &io
->msg
);
4283 req
->flags
|= REQ_F_NEED_CLEANUP
;
4287 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4288 struct io_comp_state
*cs
)
4290 struct io_async_msghdr iomsg
, *kmsg
;
4291 struct socket
*sock
;
4292 struct io_buffer
*kbuf
;
4294 int ret
, cflags
= 0;
4296 sock
= sock_from_file(req
->file
, &ret
);
4297 if (unlikely(!sock
))
4301 kmsg
= &req
->io
->msg
;
4302 kmsg
->msg
.msg_name
= &req
->io
->msg
.addr
;
4303 /* if iov is set, it's allocated already */
4305 kmsg
->iov
= kmsg
->fast_iov
;
4306 kmsg
->msg
.msg_iter
.iov
= kmsg
->iov
;
4308 ret
= io_recvmsg_copy_hdr(req
, &iomsg
);
4314 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4315 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4317 return PTR_ERR(kbuf
);
4318 kmsg
->fast_iov
[0].iov_base
= u64_to_user_ptr(kbuf
->addr
);
4319 iov_iter_init(&kmsg
->msg
.msg_iter
, READ
, kmsg
->iov
,
4320 1, req
->sr_msg
.len
);
4323 flags
= req
->sr_msg
.msg_flags
;
4324 if (flags
& MSG_DONTWAIT
)
4325 req
->flags
|= REQ_F_NOWAIT
;
4326 else if (force_nonblock
)
4327 flags
|= MSG_DONTWAIT
;
4329 ret
= __sys_recvmsg_sock(sock
, &kmsg
->msg
, req
->sr_msg
.umsg
,
4330 kmsg
->uaddr
, flags
);
4331 if (force_nonblock
&& ret
== -EAGAIN
)
4332 return io_setup_async_msg(req
, kmsg
);
4333 if (ret
== -ERESTARTSYS
)
4336 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4337 cflags
= io_put_recv_kbuf(req
);
4338 if (kmsg
->iov
!= kmsg
->fast_iov
)
4340 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
4342 req_set_fail_links(req
);
4343 __io_req_complete(req
, ret
, cflags
, cs
);
4347 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4348 struct io_comp_state
*cs
)
4350 struct io_buffer
*kbuf
;
4351 struct io_sr_msg
*sr
= &req
->sr_msg
;
4353 void __user
*buf
= sr
->buf
;
4354 struct socket
*sock
;
4357 int ret
, cflags
= 0;
4359 sock
= sock_from_file(req
->file
, &ret
);
4360 if (unlikely(!sock
))
4363 if (req
->flags
& REQ_F_BUFFER_SELECT
) {
4364 kbuf
= io_recv_buffer_select(req
, !force_nonblock
);
4366 return PTR_ERR(kbuf
);
4367 buf
= u64_to_user_ptr(kbuf
->addr
);
4370 ret
= import_single_range(READ
, buf
, sr
->len
, &iov
, &msg
.msg_iter
);
4374 msg
.msg_name
= NULL
;
4375 msg
.msg_control
= NULL
;
4376 msg
.msg_controllen
= 0;
4377 msg
.msg_namelen
= 0;
4378 msg
.msg_iocb
= NULL
;
4381 flags
= req
->sr_msg
.msg_flags
;
4382 if (flags
& MSG_DONTWAIT
)
4383 req
->flags
|= REQ_F_NOWAIT
;
4384 else if (force_nonblock
)
4385 flags
|= MSG_DONTWAIT
;
4387 ret
= sock_recvmsg(sock
, &msg
, flags
);
4388 if (force_nonblock
&& ret
== -EAGAIN
)
4390 if (ret
== -ERESTARTSYS
)
4393 if (req
->flags
& REQ_F_BUFFER_SELECTED
)
4394 cflags
= io_put_recv_kbuf(req
);
4396 req_set_fail_links(req
);
4397 __io_req_complete(req
, ret
, cflags
, cs
);
4401 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4403 struct io_accept
*accept
= &req
->accept
;
4405 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4407 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
)
4410 accept
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4411 accept
->addr_len
= u64_to_user_ptr(READ_ONCE(sqe
->addr2
));
4412 accept
->flags
= READ_ONCE(sqe
->accept_flags
);
4413 accept
->nofile
= rlimit(RLIMIT_NOFILE
);
4417 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4418 struct io_comp_state
*cs
)
4420 struct io_accept
*accept
= &req
->accept
;
4421 unsigned int file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4424 if (req
->file
->f_flags
& O_NONBLOCK
)
4425 req
->flags
|= REQ_F_NOWAIT
;
4427 ret
= __sys_accept4_file(req
->file
, file_flags
, accept
->addr
,
4428 accept
->addr_len
, accept
->flags
,
4430 if (ret
== -EAGAIN
&& force_nonblock
)
4433 if (ret
== -ERESTARTSYS
)
4435 req_set_fail_links(req
);
4437 __io_req_complete(req
, ret
, 0, cs
);
4441 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4443 struct io_connect
*conn
= &req
->connect
;
4444 struct io_async_ctx
*io
= req
->io
;
4446 if (unlikely(req
->ctx
->flags
& (IORING_SETUP_IOPOLL
|IORING_SETUP_SQPOLL
)))
4448 if (sqe
->ioprio
|| sqe
->len
|| sqe
->buf_index
|| sqe
->rw_flags
)
4451 conn
->addr
= u64_to_user_ptr(READ_ONCE(sqe
->addr
));
4452 conn
->addr_len
= READ_ONCE(sqe
->addr2
);
4457 return move_addr_to_kernel(conn
->addr
, conn
->addr_len
,
4458 &io
->connect
.address
);
4461 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4462 struct io_comp_state
*cs
)
4464 struct io_async_ctx __io
, *io
;
4465 unsigned file_flags
;
4471 ret
= move_addr_to_kernel(req
->connect
.addr
,
4472 req
->connect
.addr_len
,
4473 &__io
.connect
.address
);
4479 file_flags
= force_nonblock
? O_NONBLOCK
: 0;
4481 ret
= __sys_connect_file(req
->file
, &io
->connect
.address
,
4482 req
->connect
.addr_len
, file_flags
);
4483 if ((ret
== -EAGAIN
|| ret
== -EINPROGRESS
) && force_nonblock
) {
4486 if (io_alloc_async_ctx(req
)) {
4490 memcpy(&req
->io
->connect
, &__io
.connect
, sizeof(__io
.connect
));
4493 if (ret
== -ERESTARTSYS
)
4497 req_set_fail_links(req
);
4498 __io_req_complete(req
, ret
, 0, cs
);
4501 #else /* !CONFIG_NET */
4502 static int io_sendmsg_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4507 static int io_sendmsg(struct io_kiocb
*req
, bool force_nonblock
,
4508 struct io_comp_state
*cs
)
4513 static int io_send(struct io_kiocb
*req
, bool force_nonblock
,
4514 struct io_comp_state
*cs
)
4519 static int io_recvmsg_prep(struct io_kiocb
*req
,
4520 const struct io_uring_sqe
*sqe
)
4525 static int io_recvmsg(struct io_kiocb
*req
, bool force_nonblock
,
4526 struct io_comp_state
*cs
)
4531 static int io_recv(struct io_kiocb
*req
, bool force_nonblock
,
4532 struct io_comp_state
*cs
)
4537 static int io_accept_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4542 static int io_accept(struct io_kiocb
*req
, bool force_nonblock
,
4543 struct io_comp_state
*cs
)
4548 static int io_connect_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
4553 static int io_connect(struct io_kiocb
*req
, bool force_nonblock
,
4554 struct io_comp_state
*cs
)
4558 #endif /* CONFIG_NET */
4560 struct io_poll_table
{
4561 struct poll_table_struct pt
;
4562 struct io_kiocb
*req
;
4566 static int __io_async_wake(struct io_kiocb
*req
, struct io_poll_iocb
*poll
,
4567 __poll_t mask
, task_work_func_t func
)
4571 /* for instances that support it check for an event match first: */
4572 if (mask
&& !(mask
& poll
->events
))
4575 trace_io_uring_task_add(req
->ctx
, req
->opcode
, req
->user_data
, mask
);
4577 list_del_init(&poll
->wait
.entry
);
4580 init_task_work(&req
->task_work
, func
);
4581 percpu_ref_get(&req
->ctx
->refs
);
4584 * If this fails, then the task is exiting. When a task exits, the
4585 * work gets canceled, so just cancel this request as well instead
4586 * of executing it. We can't safely execute it anyway, as we may not
4587 * have the needed state needed for it anyway.
4589 ret
= io_req_task_work_add(req
, &req
->task_work
);
4590 if (unlikely(ret
)) {
4591 struct task_struct
*tsk
;
4593 WRITE_ONCE(poll
->canceled
, true);
4594 tsk
= io_wq_get_task(req
->ctx
->io_wq
);
4595 task_work_add(tsk
, &req
->task_work
, 0);
4596 wake_up_process(tsk
);
4601 static bool io_poll_rewait(struct io_kiocb
*req
, struct io_poll_iocb
*poll
)
4602 __acquires(&req
->ctx
->completion_lock
)
4604 struct io_ring_ctx
*ctx
= req
->ctx
;
4606 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4607 struct poll_table_struct pt
= { ._key
= poll
->events
};
4609 req
->result
= vfs_poll(req
->file
, &pt
) & poll
->events
;
4612 spin_lock_irq(&ctx
->completion_lock
);
4613 if (!req
->result
&& !READ_ONCE(poll
->canceled
)) {
4614 add_wait_queue(poll
->head
, &poll
->wait
);
4621 static struct io_poll_iocb
*io_poll_get_double(struct io_kiocb
*req
)
4623 /* pure poll stashes this in ->io, poll driven retry elsewhere */
4624 if (req
->opcode
== IORING_OP_POLL_ADD
)
4625 return (struct io_poll_iocb
*) req
->io
;
4626 return req
->apoll
->double_poll
;
4629 static struct io_poll_iocb
*io_poll_get_single(struct io_kiocb
*req
)
4631 if (req
->opcode
== IORING_OP_POLL_ADD
)
4633 return &req
->apoll
->poll
;
4636 static void io_poll_remove_double(struct io_kiocb
*req
)
4638 struct io_poll_iocb
*poll
= io_poll_get_double(req
);
4640 lockdep_assert_held(&req
->ctx
->completion_lock
);
4642 if (poll
&& poll
->head
) {
4643 struct wait_queue_head
*head
= poll
->head
;
4645 spin_lock(&head
->lock
);
4646 list_del_init(&poll
->wait
.entry
);
4647 if (poll
->wait
.private)
4648 refcount_dec(&req
->refs
);
4650 spin_unlock(&head
->lock
);
4654 static void io_poll_complete(struct io_kiocb
*req
, __poll_t mask
, int error
)
4656 struct io_ring_ctx
*ctx
= req
->ctx
;
4658 io_poll_remove_double(req
);
4659 req
->poll
.done
= true;
4660 io_cqring_fill_event(req
, error
? error
: mangle_poll(mask
));
4661 io_commit_cqring(ctx
);
4664 static void io_poll_task_handler(struct io_kiocb
*req
, struct io_kiocb
**nxt
)
4666 struct io_ring_ctx
*ctx
= req
->ctx
;
4668 if (io_poll_rewait(req
, &req
->poll
)) {
4669 spin_unlock_irq(&ctx
->completion_lock
);
4673 hash_del(&req
->hash_node
);
4674 io_poll_complete(req
, req
->result
, 0);
4675 req
->flags
|= REQ_F_COMP_LOCKED
;
4676 *nxt
= io_put_req_find_next(req
);
4677 spin_unlock_irq(&ctx
->completion_lock
);
4679 io_cqring_ev_posted(ctx
);
4682 static void io_poll_task_func(struct callback_head
*cb
)
4684 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4685 struct io_ring_ctx
*ctx
= req
->ctx
;
4686 struct io_kiocb
*nxt
= NULL
;
4688 io_poll_task_handler(req
, &nxt
);
4690 __io_req_task_submit(nxt
);
4691 percpu_ref_put(&ctx
->refs
);
4694 static int io_poll_double_wake(struct wait_queue_entry
*wait
, unsigned mode
,
4695 int sync
, void *key
)
4697 struct io_kiocb
*req
= wait
->private;
4698 struct io_poll_iocb
*poll
= io_poll_get_single(req
);
4699 __poll_t mask
= key_to_poll(key
);
4701 /* for instances that support it check for an event match first: */
4702 if (mask
&& !(mask
& poll
->events
))
4705 if (poll
&& poll
->head
) {
4708 spin_lock(&poll
->head
->lock
);
4709 done
= list_empty(&poll
->wait
.entry
);
4711 list_del_init(&poll
->wait
.entry
);
4712 /* make sure double remove sees this as being gone */
4713 wait
->private = NULL
;
4714 spin_unlock(&poll
->head
->lock
);
4716 __io_async_wake(req
, poll
, mask
, io_poll_task_func
);
4718 refcount_dec(&req
->refs
);
4722 static void io_init_poll_iocb(struct io_poll_iocb
*poll
, __poll_t events
,
4723 wait_queue_func_t wake_func
)
4727 poll
->canceled
= false;
4728 poll
->events
= events
;
4729 INIT_LIST_HEAD(&poll
->wait
.entry
);
4730 init_waitqueue_func_entry(&poll
->wait
, wake_func
);
4733 static void __io_queue_proc(struct io_poll_iocb
*poll
, struct io_poll_table
*pt
,
4734 struct wait_queue_head
*head
,
4735 struct io_poll_iocb
**poll_ptr
)
4737 struct io_kiocb
*req
= pt
->req
;
4740 * If poll->head is already set, it's because the file being polled
4741 * uses multiple waitqueues for poll handling (eg one for read, one
4742 * for write). Setup a separate io_poll_iocb if this happens.
4744 if (unlikely(poll
->head
)) {
4745 /* already have a 2nd entry, fail a third attempt */
4747 pt
->error
= -EINVAL
;
4750 poll
= kmalloc(sizeof(*poll
), GFP_ATOMIC
);
4752 pt
->error
= -ENOMEM
;
4755 io_init_poll_iocb(poll
, req
->poll
.events
, io_poll_double_wake
);
4756 refcount_inc(&req
->refs
);
4757 poll
->wait
.private = req
;
4764 if (poll
->events
& EPOLLEXCLUSIVE
)
4765 add_wait_queue_exclusive(head
, &poll
->wait
);
4767 add_wait_queue(head
, &poll
->wait
);
4770 static void io_async_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
4771 struct poll_table_struct
*p
)
4773 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
4774 struct async_poll
*apoll
= pt
->req
->apoll
;
4776 __io_queue_proc(&apoll
->poll
, pt
, head
, &apoll
->double_poll
);
4779 static void io_async_task_func(struct callback_head
*cb
)
4781 struct io_kiocb
*req
= container_of(cb
, struct io_kiocb
, task_work
);
4782 struct async_poll
*apoll
= req
->apoll
;
4783 struct io_ring_ctx
*ctx
= req
->ctx
;
4785 trace_io_uring_task_run(req
->ctx
, req
->opcode
, req
->user_data
);
4787 if (io_poll_rewait(req
, &apoll
->poll
)) {
4788 spin_unlock_irq(&ctx
->completion_lock
);
4789 percpu_ref_put(&ctx
->refs
);
4793 /* If req is still hashed, it cannot have been canceled. Don't check. */
4794 if (hash_hashed(&req
->hash_node
))
4795 hash_del(&req
->hash_node
);
4797 io_poll_remove_double(req
);
4798 spin_unlock_irq(&ctx
->completion_lock
);
4800 if (!READ_ONCE(apoll
->poll
.canceled
))
4801 __io_req_task_submit(req
);
4803 __io_req_task_cancel(req
, -ECANCELED
);
4805 percpu_ref_put(&ctx
->refs
);
4806 kfree(apoll
->double_poll
);
4810 static int io_async_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
4813 struct io_kiocb
*req
= wait
->private;
4814 struct io_poll_iocb
*poll
= &req
->apoll
->poll
;
4816 trace_io_uring_poll_wake(req
->ctx
, req
->opcode
, req
->user_data
,
4819 return __io_async_wake(req
, poll
, key_to_poll(key
), io_async_task_func
);
4822 static void io_poll_req_insert(struct io_kiocb
*req
)
4824 struct io_ring_ctx
*ctx
= req
->ctx
;
4825 struct hlist_head
*list
;
4827 list
= &ctx
->cancel_hash
[hash_long(req
->user_data
, ctx
->cancel_hash_bits
)];
4828 hlist_add_head(&req
->hash_node
, list
);
4831 static __poll_t
__io_arm_poll_handler(struct io_kiocb
*req
,
4832 struct io_poll_iocb
*poll
,
4833 struct io_poll_table
*ipt
, __poll_t mask
,
4834 wait_queue_func_t wake_func
)
4835 __acquires(&ctx
->completion_lock
)
4837 struct io_ring_ctx
*ctx
= req
->ctx
;
4838 bool cancel
= false;
4840 io_init_poll_iocb(poll
, mask
, wake_func
);
4841 poll
->file
= req
->file
;
4842 poll
->wait
.private = req
;
4844 ipt
->pt
._key
= mask
;
4846 ipt
->error
= -EINVAL
;
4848 mask
= vfs_poll(req
->file
, &ipt
->pt
) & poll
->events
;
4850 spin_lock_irq(&ctx
->completion_lock
);
4851 if (likely(poll
->head
)) {
4852 spin_lock(&poll
->head
->lock
);
4853 if (unlikely(list_empty(&poll
->wait
.entry
))) {
4859 if (mask
|| ipt
->error
)
4860 list_del_init(&poll
->wait
.entry
);
4862 WRITE_ONCE(poll
->canceled
, true);
4863 else if (!poll
->done
) /* actually waiting for an event */
4864 io_poll_req_insert(req
);
4865 spin_unlock(&poll
->head
->lock
);
4871 static bool io_arm_poll_handler(struct io_kiocb
*req
)
4873 const struct io_op_def
*def
= &io_op_defs
[req
->opcode
];
4874 struct io_ring_ctx
*ctx
= req
->ctx
;
4875 struct async_poll
*apoll
;
4876 struct io_poll_table ipt
;
4879 if (!req
->file
|| !file_can_poll(req
->file
))
4881 if (req
->flags
& REQ_F_POLLED
)
4883 if (!def
->pollin
&& !def
->pollout
)
4886 apoll
= kmalloc(sizeof(*apoll
), GFP_ATOMIC
);
4887 if (unlikely(!apoll
))
4889 apoll
->double_poll
= NULL
;
4891 req
->flags
|= REQ_F_POLLED
;
4892 io_get_req_task(req
);
4894 INIT_HLIST_NODE(&req
->hash_node
);
4898 mask
|= POLLIN
| POLLRDNORM
;
4900 mask
|= POLLOUT
| POLLWRNORM
;
4901 mask
|= POLLERR
| POLLPRI
;
4903 ipt
.pt
._qproc
= io_async_queue_proc
;
4905 ret
= __io_arm_poll_handler(req
, &apoll
->poll
, &ipt
, mask
,
4907 if (ret
|| ipt
.error
) {
4908 io_poll_remove_double(req
);
4909 spin_unlock_irq(&ctx
->completion_lock
);
4910 kfree(apoll
->double_poll
);
4914 spin_unlock_irq(&ctx
->completion_lock
);
4915 trace_io_uring_poll_arm(ctx
, req
->opcode
, req
->user_data
, mask
,
4916 apoll
->poll
.events
);
4920 static bool __io_poll_remove_one(struct io_kiocb
*req
,
4921 struct io_poll_iocb
*poll
)
4923 bool do_complete
= false;
4925 spin_lock(&poll
->head
->lock
);
4926 WRITE_ONCE(poll
->canceled
, true);
4927 if (!list_empty(&poll
->wait
.entry
)) {
4928 list_del_init(&poll
->wait
.entry
);
4931 spin_unlock(&poll
->head
->lock
);
4932 hash_del(&req
->hash_node
);
4936 static bool io_poll_remove_one(struct io_kiocb
*req
)
4940 io_poll_remove_double(req
);
4942 if (req
->opcode
== IORING_OP_POLL_ADD
) {
4943 do_complete
= __io_poll_remove_one(req
, &req
->poll
);
4945 struct async_poll
*apoll
= req
->apoll
;
4947 /* non-poll requests have submit ref still */
4948 do_complete
= __io_poll_remove_one(req
, &apoll
->poll
);
4951 kfree(apoll
->double_poll
);
4957 io_cqring_fill_event(req
, -ECANCELED
);
4958 io_commit_cqring(req
->ctx
);
4959 req
->flags
|= REQ_F_COMP_LOCKED
;
4960 req_set_fail_links(req
);
4967 static void io_poll_remove_all(struct io_ring_ctx
*ctx
)
4969 struct hlist_node
*tmp
;
4970 struct io_kiocb
*req
;
4973 spin_lock_irq(&ctx
->completion_lock
);
4974 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
4975 struct hlist_head
*list
;
4977 list
= &ctx
->cancel_hash
[i
];
4978 hlist_for_each_entry_safe(req
, tmp
, list
, hash_node
)
4979 posted
+= io_poll_remove_one(req
);
4981 spin_unlock_irq(&ctx
->completion_lock
);
4984 io_cqring_ev_posted(ctx
);
4987 static int io_poll_cancel(struct io_ring_ctx
*ctx
, __u64 sqe_addr
)
4989 struct hlist_head
*list
;
4990 struct io_kiocb
*req
;
4992 list
= &ctx
->cancel_hash
[hash_long(sqe_addr
, ctx
->cancel_hash_bits
)];
4993 hlist_for_each_entry(req
, list
, hash_node
) {
4994 if (sqe_addr
!= req
->user_data
)
4996 if (io_poll_remove_one(req
))
5004 static int io_poll_remove_prep(struct io_kiocb
*req
,
5005 const struct io_uring_sqe
*sqe
)
5007 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5009 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
||
5013 req
->poll
.addr
= READ_ONCE(sqe
->addr
);
5018 * Find a running poll command that matches one specified in sqe->addr,
5019 * and remove it if found.
5021 static int io_poll_remove(struct io_kiocb
*req
)
5023 struct io_ring_ctx
*ctx
= req
->ctx
;
5027 addr
= req
->poll
.addr
;
5028 spin_lock_irq(&ctx
->completion_lock
);
5029 ret
= io_poll_cancel(ctx
, addr
);
5030 spin_unlock_irq(&ctx
->completion_lock
);
5033 req_set_fail_links(req
);
5034 io_req_complete(req
, ret
);
5038 static int io_poll_wake(struct wait_queue_entry
*wait
, unsigned mode
, int sync
,
5041 struct io_kiocb
*req
= wait
->private;
5042 struct io_poll_iocb
*poll
= &req
->poll
;
5044 return __io_async_wake(req
, poll
, key_to_poll(key
), io_poll_task_func
);
5047 static void io_poll_queue_proc(struct file
*file
, struct wait_queue_head
*head
,
5048 struct poll_table_struct
*p
)
5050 struct io_poll_table
*pt
= container_of(p
, struct io_poll_table
, pt
);
5052 __io_queue_proc(&pt
->req
->poll
, pt
, head
, (struct io_poll_iocb
**) &pt
->req
->io
);
5055 static int io_poll_add_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5057 struct io_poll_iocb
*poll
= &req
->poll
;
5060 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5062 if (sqe
->addr
|| sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->buf_index
)
5067 events
= READ_ONCE(sqe
->poll32_events
);
5069 events
= swahw32(events
);
5071 poll
->events
= demangle_poll(events
) | EPOLLERR
| EPOLLHUP
|
5072 (events
& EPOLLEXCLUSIVE
);
5074 io_get_req_task(req
);
5078 static int io_poll_add(struct io_kiocb
*req
)
5080 struct io_poll_iocb
*poll
= &req
->poll
;
5081 struct io_ring_ctx
*ctx
= req
->ctx
;
5082 struct io_poll_table ipt
;
5085 INIT_HLIST_NODE(&req
->hash_node
);
5086 ipt
.pt
._qproc
= io_poll_queue_proc
;
5088 mask
= __io_arm_poll_handler(req
, &req
->poll
, &ipt
, poll
->events
,
5091 if (mask
) { /* no async, we'd stolen it */
5093 io_poll_complete(req
, mask
, 0);
5095 spin_unlock_irq(&ctx
->completion_lock
);
5098 io_cqring_ev_posted(ctx
);
5104 static enum hrtimer_restart
io_timeout_fn(struct hrtimer
*timer
)
5106 struct io_timeout_data
*data
= container_of(timer
,
5107 struct io_timeout_data
, timer
);
5108 struct io_kiocb
*req
= data
->req
;
5109 struct io_ring_ctx
*ctx
= req
->ctx
;
5110 unsigned long flags
;
5112 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5113 atomic_set(&req
->ctx
->cq_timeouts
,
5114 atomic_read(&req
->ctx
->cq_timeouts
) + 1);
5117 * We could be racing with timeout deletion. If the list is empty,
5118 * then timeout lookup already found it and will be handling it.
5120 if (!list_empty(&req
->timeout
.list
))
5121 list_del_init(&req
->timeout
.list
);
5123 io_cqring_fill_event(req
, -ETIME
);
5124 io_commit_cqring(ctx
);
5125 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5127 io_cqring_ev_posted(ctx
);
5128 req_set_fail_links(req
);
5130 return HRTIMER_NORESTART
;
5133 static int __io_timeout_cancel(struct io_kiocb
*req
)
5137 list_del_init(&req
->timeout
.list
);
5139 ret
= hrtimer_try_to_cancel(&req
->io
->timeout
.timer
);
5143 req_set_fail_links(req
);
5144 req
->flags
|= REQ_F_COMP_LOCKED
;
5145 io_cqring_fill_event(req
, -ECANCELED
);
5150 static int io_timeout_cancel(struct io_ring_ctx
*ctx
, __u64 user_data
)
5152 struct io_kiocb
*req
;
5155 list_for_each_entry(req
, &ctx
->timeout_list
, timeout
.list
) {
5156 if (user_data
== req
->user_data
) {
5165 return __io_timeout_cancel(req
);
5168 static int io_timeout_remove_prep(struct io_kiocb
*req
,
5169 const struct io_uring_sqe
*sqe
)
5171 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5173 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5175 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
)
5178 req
->timeout
.addr
= READ_ONCE(sqe
->addr
);
5179 req
->timeout
.flags
= READ_ONCE(sqe
->timeout_flags
);
5180 if (req
->timeout
.flags
)
5187 * Remove or update an existing timeout command
5189 static int io_timeout_remove(struct io_kiocb
*req
)
5191 struct io_ring_ctx
*ctx
= req
->ctx
;
5194 spin_lock_irq(&ctx
->completion_lock
);
5195 ret
= io_timeout_cancel(ctx
, req
->timeout
.addr
);
5197 io_cqring_fill_event(req
, ret
);
5198 io_commit_cqring(ctx
);
5199 spin_unlock_irq(&ctx
->completion_lock
);
5200 io_cqring_ev_posted(ctx
);
5202 req_set_fail_links(req
);
5207 static int io_timeout_prep(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5208 bool is_timeout_link
)
5210 struct io_timeout_data
*data
;
5212 u32 off
= READ_ONCE(sqe
->off
);
5214 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5216 if (sqe
->ioprio
|| sqe
->buf_index
|| sqe
->len
!= 1)
5218 if (off
&& is_timeout_link
)
5220 flags
= READ_ONCE(sqe
->timeout_flags
);
5221 if (flags
& ~IORING_TIMEOUT_ABS
)
5224 req
->timeout
.off
= off
;
5226 if (!req
->io
&& io_alloc_async_ctx(req
))
5229 data
= &req
->io
->timeout
;
5232 if (get_timespec64(&data
->ts
, u64_to_user_ptr(sqe
->addr
)))
5235 if (flags
& IORING_TIMEOUT_ABS
)
5236 data
->mode
= HRTIMER_MODE_ABS
;
5238 data
->mode
= HRTIMER_MODE_REL
;
5240 hrtimer_init(&data
->timer
, CLOCK_MONOTONIC
, data
->mode
);
5244 static int io_timeout(struct io_kiocb
*req
)
5246 struct io_ring_ctx
*ctx
= req
->ctx
;
5247 struct io_timeout_data
*data
= &req
->io
->timeout
;
5248 struct list_head
*entry
;
5249 u32 tail
, off
= req
->timeout
.off
;
5251 spin_lock_irq(&ctx
->completion_lock
);
5254 * sqe->off holds how many events that need to occur for this
5255 * timeout event to be satisfied. If it isn't set, then this is
5256 * a pure timeout request, sequence isn't used.
5258 if (io_is_timeout_noseq(req
)) {
5259 entry
= ctx
->timeout_list
.prev
;
5263 tail
= ctx
->cached_cq_tail
- atomic_read(&ctx
->cq_timeouts
);
5264 req
->timeout
.target_seq
= tail
+ off
;
5267 * Insertion sort, ensuring the first entry in the list is always
5268 * the one we need first.
5270 list_for_each_prev(entry
, &ctx
->timeout_list
) {
5271 struct io_kiocb
*nxt
= list_entry(entry
, struct io_kiocb
,
5274 if (io_is_timeout_noseq(nxt
))
5276 /* nxt.seq is behind @tail, otherwise would've been completed */
5277 if (off
>= nxt
->timeout
.target_seq
- tail
)
5281 list_add(&req
->timeout
.list
, entry
);
5282 data
->timer
.function
= io_timeout_fn
;
5283 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
), data
->mode
);
5284 spin_unlock_irq(&ctx
->completion_lock
);
5288 static bool io_cancel_cb(struct io_wq_work
*work
, void *data
)
5290 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5292 return req
->user_data
== (unsigned long) data
;
5295 static int io_async_cancel_one(struct io_ring_ctx
*ctx
, void *sqe_addr
)
5297 enum io_wq_cancel cancel_ret
;
5300 cancel_ret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_cb
, sqe_addr
, false);
5301 switch (cancel_ret
) {
5302 case IO_WQ_CANCEL_OK
:
5305 case IO_WQ_CANCEL_RUNNING
:
5308 case IO_WQ_CANCEL_NOTFOUND
:
5316 static void io_async_find_and_cancel(struct io_ring_ctx
*ctx
,
5317 struct io_kiocb
*req
, __u64 sqe_addr
,
5320 unsigned long flags
;
5323 ret
= io_async_cancel_one(ctx
, (void *) (unsigned long) sqe_addr
);
5324 if (ret
!= -ENOENT
) {
5325 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5329 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
5330 ret
= io_timeout_cancel(ctx
, sqe_addr
);
5333 ret
= io_poll_cancel(ctx
, sqe_addr
);
5337 io_cqring_fill_event(req
, ret
);
5338 io_commit_cqring(ctx
);
5339 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
5340 io_cqring_ev_posted(ctx
);
5343 req_set_fail_links(req
);
5347 static int io_async_cancel_prep(struct io_kiocb
*req
,
5348 const struct io_uring_sqe
*sqe
)
5350 if (unlikely(req
->ctx
->flags
& IORING_SETUP_IOPOLL
))
5352 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5354 if (sqe
->ioprio
|| sqe
->off
|| sqe
->len
|| sqe
->cancel_flags
)
5357 req
->cancel
.addr
= READ_ONCE(sqe
->addr
);
5361 static int io_async_cancel(struct io_kiocb
*req
)
5363 struct io_ring_ctx
*ctx
= req
->ctx
;
5365 io_async_find_and_cancel(ctx
, req
, req
->cancel
.addr
, 0);
5369 static int io_files_update_prep(struct io_kiocb
*req
,
5370 const struct io_uring_sqe
*sqe
)
5372 if (unlikely(req
->flags
& (REQ_F_FIXED_FILE
| REQ_F_BUFFER_SELECT
)))
5374 if (sqe
->ioprio
|| sqe
->rw_flags
)
5377 req
->files_update
.offset
= READ_ONCE(sqe
->off
);
5378 req
->files_update
.nr_args
= READ_ONCE(sqe
->len
);
5379 if (!req
->files_update
.nr_args
)
5381 req
->files_update
.arg
= READ_ONCE(sqe
->addr
);
5385 static int io_files_update(struct io_kiocb
*req
, bool force_nonblock
,
5386 struct io_comp_state
*cs
)
5388 struct io_ring_ctx
*ctx
= req
->ctx
;
5389 struct io_uring_files_update up
;
5395 up
.offset
= req
->files_update
.offset
;
5396 up
.fds
= req
->files_update
.arg
;
5398 mutex_lock(&ctx
->uring_lock
);
5399 ret
= __io_sqe_files_update(ctx
, &up
, req
->files_update
.nr_args
);
5400 mutex_unlock(&ctx
->uring_lock
);
5403 req_set_fail_links(req
);
5404 __io_req_complete(req
, ret
, 0, cs
);
5408 static int io_req_defer_prep(struct io_kiocb
*req
,
5409 const struct io_uring_sqe
*sqe
)
5416 if (io_alloc_async_ctx(req
))
5418 ret
= io_prep_work_files(req
);
5422 switch (req
->opcode
) {
5425 case IORING_OP_READV
:
5426 case IORING_OP_READ_FIXED
:
5427 case IORING_OP_READ
:
5428 ret
= io_read_prep(req
, sqe
, true);
5430 case IORING_OP_WRITEV
:
5431 case IORING_OP_WRITE_FIXED
:
5432 case IORING_OP_WRITE
:
5433 ret
= io_write_prep(req
, sqe
, true);
5435 case IORING_OP_POLL_ADD
:
5436 ret
= io_poll_add_prep(req
, sqe
);
5438 case IORING_OP_POLL_REMOVE
:
5439 ret
= io_poll_remove_prep(req
, sqe
);
5441 case IORING_OP_FSYNC
:
5442 ret
= io_prep_fsync(req
, sqe
);
5444 case IORING_OP_SYNC_FILE_RANGE
:
5445 ret
= io_prep_sfr(req
, sqe
);
5447 case IORING_OP_SENDMSG
:
5448 case IORING_OP_SEND
:
5449 ret
= io_sendmsg_prep(req
, sqe
);
5451 case IORING_OP_RECVMSG
:
5452 case IORING_OP_RECV
:
5453 ret
= io_recvmsg_prep(req
, sqe
);
5455 case IORING_OP_CONNECT
:
5456 ret
= io_connect_prep(req
, sqe
);
5458 case IORING_OP_TIMEOUT
:
5459 ret
= io_timeout_prep(req
, sqe
, false);
5461 case IORING_OP_TIMEOUT_REMOVE
:
5462 ret
= io_timeout_remove_prep(req
, sqe
);
5464 case IORING_OP_ASYNC_CANCEL
:
5465 ret
= io_async_cancel_prep(req
, sqe
);
5467 case IORING_OP_LINK_TIMEOUT
:
5468 ret
= io_timeout_prep(req
, sqe
, true);
5470 case IORING_OP_ACCEPT
:
5471 ret
= io_accept_prep(req
, sqe
);
5473 case IORING_OP_FALLOCATE
:
5474 ret
= io_fallocate_prep(req
, sqe
);
5476 case IORING_OP_OPENAT
:
5477 ret
= io_openat_prep(req
, sqe
);
5479 case IORING_OP_CLOSE
:
5480 ret
= io_close_prep(req
, sqe
);
5482 case IORING_OP_FILES_UPDATE
:
5483 ret
= io_files_update_prep(req
, sqe
);
5485 case IORING_OP_STATX
:
5486 ret
= io_statx_prep(req
, sqe
);
5488 case IORING_OP_FADVISE
:
5489 ret
= io_fadvise_prep(req
, sqe
);
5491 case IORING_OP_MADVISE
:
5492 ret
= io_madvise_prep(req
, sqe
);
5494 case IORING_OP_OPENAT2
:
5495 ret
= io_openat2_prep(req
, sqe
);
5497 case IORING_OP_EPOLL_CTL
:
5498 ret
= io_epoll_ctl_prep(req
, sqe
);
5500 case IORING_OP_SPLICE
:
5501 ret
= io_splice_prep(req
, sqe
);
5503 case IORING_OP_PROVIDE_BUFFERS
:
5504 ret
= io_provide_buffers_prep(req
, sqe
);
5506 case IORING_OP_REMOVE_BUFFERS
:
5507 ret
= io_remove_buffers_prep(req
, sqe
);
5510 ret
= io_tee_prep(req
, sqe
);
5513 printk_once(KERN_WARNING
"io_uring: unhandled opcode %d\n",
5522 static u32
io_get_sequence(struct io_kiocb
*req
)
5524 struct io_kiocb
*pos
;
5525 struct io_ring_ctx
*ctx
= req
->ctx
;
5526 u32 total_submitted
, nr_reqs
= 1;
5528 if (req
->flags
& REQ_F_LINK_HEAD
)
5529 list_for_each_entry(pos
, &req
->link_list
, link_list
)
5532 total_submitted
= ctx
->cached_sq_head
- ctx
->cached_sq_dropped
;
5533 return total_submitted
- nr_reqs
;
5536 static int io_req_defer(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
)
5538 struct io_ring_ctx
*ctx
= req
->ctx
;
5539 struct io_defer_entry
*de
;
5543 /* Still need defer if there is pending req in defer list. */
5544 if (likely(list_empty_careful(&ctx
->defer_list
) &&
5545 !(req
->flags
& REQ_F_IO_DRAIN
)))
5548 seq
= io_get_sequence(req
);
5549 /* Still a chance to pass the sequence check */
5550 if (!req_need_defer(req
, seq
) && list_empty_careful(&ctx
->defer_list
))
5554 ret
= io_req_defer_prep(req
, sqe
);
5558 io_prep_async_link(req
);
5559 de
= kmalloc(sizeof(*de
), GFP_KERNEL
);
5563 spin_lock_irq(&ctx
->completion_lock
);
5564 if (!req_need_defer(req
, seq
) && list_empty(&ctx
->defer_list
)) {
5565 spin_unlock_irq(&ctx
->completion_lock
);
5567 io_queue_async_work(req
);
5568 return -EIOCBQUEUED
;
5571 trace_io_uring_defer(ctx
, req
, req
->user_data
);
5574 list_add_tail(&de
->list
, &ctx
->defer_list
);
5575 spin_unlock_irq(&ctx
->completion_lock
);
5576 return -EIOCBQUEUED
;
5579 static void __io_clean_op(struct io_kiocb
*req
)
5581 struct io_async_ctx
*io
= req
->io
;
5583 if (req
->flags
& REQ_F_BUFFER_SELECTED
) {
5584 switch (req
->opcode
) {
5585 case IORING_OP_READV
:
5586 case IORING_OP_READ_FIXED
:
5587 case IORING_OP_READ
:
5588 kfree((void *)(unsigned long)req
->rw
.addr
);
5590 case IORING_OP_RECVMSG
:
5591 case IORING_OP_RECV
:
5592 kfree(req
->sr_msg
.kbuf
);
5595 req
->flags
&= ~REQ_F_BUFFER_SELECTED
;
5598 if (req
->flags
& REQ_F_NEED_CLEANUP
) {
5599 switch (req
->opcode
) {
5600 case IORING_OP_READV
:
5601 case IORING_OP_READ_FIXED
:
5602 case IORING_OP_READ
:
5603 case IORING_OP_WRITEV
:
5604 case IORING_OP_WRITE_FIXED
:
5605 case IORING_OP_WRITE
:
5606 if (io
->rw
.free_iovec
)
5607 kfree(io
->rw
.free_iovec
);
5609 case IORING_OP_RECVMSG
:
5610 case IORING_OP_SENDMSG
:
5611 if (io
->msg
.iov
!= io
->msg
.fast_iov
)
5614 case IORING_OP_SPLICE
:
5616 io_put_file(req
, req
->splice
.file_in
,
5617 (req
->splice
.flags
& SPLICE_F_FD_IN_FIXED
));
5620 req
->flags
&= ~REQ_F_NEED_CLEANUP
;
5623 if (req
->flags
& REQ_F_INFLIGHT
) {
5624 struct io_ring_ctx
*ctx
= req
->ctx
;
5625 unsigned long flags
;
5627 spin_lock_irqsave(&ctx
->inflight_lock
, flags
);
5628 list_del(&req
->inflight_entry
);
5629 if (waitqueue_active(&ctx
->inflight_wait
))
5630 wake_up(&ctx
->inflight_wait
);
5631 spin_unlock_irqrestore(&ctx
->inflight_lock
, flags
);
5632 req
->flags
&= ~REQ_F_INFLIGHT
;
5636 static int io_issue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
5637 bool force_nonblock
, struct io_comp_state
*cs
)
5639 struct io_ring_ctx
*ctx
= req
->ctx
;
5642 switch (req
->opcode
) {
5644 ret
= io_nop(req
, cs
);
5646 case IORING_OP_READV
:
5647 case IORING_OP_READ_FIXED
:
5648 case IORING_OP_READ
:
5650 ret
= io_read_prep(req
, sqe
, force_nonblock
);
5654 ret
= io_read(req
, force_nonblock
, cs
);
5656 case IORING_OP_WRITEV
:
5657 case IORING_OP_WRITE_FIXED
:
5658 case IORING_OP_WRITE
:
5660 ret
= io_write_prep(req
, sqe
, force_nonblock
);
5664 ret
= io_write(req
, force_nonblock
, cs
);
5666 case IORING_OP_FSYNC
:
5668 ret
= io_prep_fsync(req
, sqe
);
5672 ret
= io_fsync(req
, force_nonblock
);
5674 case IORING_OP_POLL_ADD
:
5676 ret
= io_poll_add_prep(req
, sqe
);
5680 ret
= io_poll_add(req
);
5682 case IORING_OP_POLL_REMOVE
:
5684 ret
= io_poll_remove_prep(req
, sqe
);
5688 ret
= io_poll_remove(req
);
5690 case IORING_OP_SYNC_FILE_RANGE
:
5692 ret
= io_prep_sfr(req
, sqe
);
5696 ret
= io_sync_file_range(req
, force_nonblock
);
5698 case IORING_OP_SENDMSG
:
5699 case IORING_OP_SEND
:
5701 ret
= io_sendmsg_prep(req
, sqe
);
5705 if (req
->opcode
== IORING_OP_SENDMSG
)
5706 ret
= io_sendmsg(req
, force_nonblock
, cs
);
5708 ret
= io_send(req
, force_nonblock
, cs
);
5710 case IORING_OP_RECVMSG
:
5711 case IORING_OP_RECV
:
5713 ret
= io_recvmsg_prep(req
, sqe
);
5717 if (req
->opcode
== IORING_OP_RECVMSG
)
5718 ret
= io_recvmsg(req
, force_nonblock
, cs
);
5720 ret
= io_recv(req
, force_nonblock
, cs
);
5722 case IORING_OP_TIMEOUT
:
5724 ret
= io_timeout_prep(req
, sqe
, false);
5728 ret
= io_timeout(req
);
5730 case IORING_OP_TIMEOUT_REMOVE
:
5732 ret
= io_timeout_remove_prep(req
, sqe
);
5736 ret
= io_timeout_remove(req
);
5738 case IORING_OP_ACCEPT
:
5740 ret
= io_accept_prep(req
, sqe
);
5744 ret
= io_accept(req
, force_nonblock
, cs
);
5746 case IORING_OP_CONNECT
:
5748 ret
= io_connect_prep(req
, sqe
);
5752 ret
= io_connect(req
, force_nonblock
, cs
);
5754 case IORING_OP_ASYNC_CANCEL
:
5756 ret
= io_async_cancel_prep(req
, sqe
);
5760 ret
= io_async_cancel(req
);
5762 case IORING_OP_FALLOCATE
:
5764 ret
= io_fallocate_prep(req
, sqe
);
5768 ret
= io_fallocate(req
, force_nonblock
);
5770 case IORING_OP_OPENAT
:
5772 ret
= io_openat_prep(req
, sqe
);
5776 ret
= io_openat(req
, force_nonblock
);
5778 case IORING_OP_CLOSE
:
5780 ret
= io_close_prep(req
, sqe
);
5784 ret
= io_close(req
, force_nonblock
, cs
);
5786 case IORING_OP_FILES_UPDATE
:
5788 ret
= io_files_update_prep(req
, sqe
);
5792 ret
= io_files_update(req
, force_nonblock
, cs
);
5794 case IORING_OP_STATX
:
5796 ret
= io_statx_prep(req
, sqe
);
5800 ret
= io_statx(req
, force_nonblock
);
5802 case IORING_OP_FADVISE
:
5804 ret
= io_fadvise_prep(req
, sqe
);
5808 ret
= io_fadvise(req
, force_nonblock
);
5810 case IORING_OP_MADVISE
:
5812 ret
= io_madvise_prep(req
, sqe
);
5816 ret
= io_madvise(req
, force_nonblock
);
5818 case IORING_OP_OPENAT2
:
5820 ret
= io_openat2_prep(req
, sqe
);
5824 ret
= io_openat2(req
, force_nonblock
);
5826 case IORING_OP_EPOLL_CTL
:
5828 ret
= io_epoll_ctl_prep(req
, sqe
);
5832 ret
= io_epoll_ctl(req
, force_nonblock
, cs
);
5834 case IORING_OP_SPLICE
:
5836 ret
= io_splice_prep(req
, sqe
);
5840 ret
= io_splice(req
, force_nonblock
);
5842 case IORING_OP_PROVIDE_BUFFERS
:
5844 ret
= io_provide_buffers_prep(req
, sqe
);
5848 ret
= io_provide_buffers(req
, force_nonblock
, cs
);
5850 case IORING_OP_REMOVE_BUFFERS
:
5852 ret
= io_remove_buffers_prep(req
, sqe
);
5856 ret
= io_remove_buffers(req
, force_nonblock
, cs
);
5860 ret
= io_tee_prep(req
, sqe
);
5864 ret
= io_tee(req
, force_nonblock
);
5874 /* If the op doesn't have a file, we're not polling for it */
5875 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) && req
->file
) {
5876 const bool in_async
= io_wq_current_is_worker();
5878 /* workqueue context doesn't hold uring_lock, grab it now */
5880 mutex_lock(&ctx
->uring_lock
);
5882 io_iopoll_req_issued(req
);
5885 mutex_unlock(&ctx
->uring_lock
);
5891 static struct io_wq_work
*io_wq_submit_work(struct io_wq_work
*work
)
5893 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
5894 struct io_kiocb
*timeout
;
5897 timeout
= io_prep_linked_timeout(req
);
5899 io_queue_linked_timeout(timeout
);
5901 /* if NO_CANCEL is set, we must still run the work */
5902 if ((work
->flags
& (IO_WQ_WORK_CANCEL
|IO_WQ_WORK_NO_CANCEL
)) ==
5903 IO_WQ_WORK_CANCEL
) {
5909 ret
= io_issue_sqe(req
, NULL
, false, NULL
);
5911 * We can get EAGAIN for polled IO even though we're
5912 * forcing a sync submission from here, since we can't
5913 * wait for request slots on the block side.
5922 req_set_fail_links(req
);
5923 io_req_complete(req
, ret
);
5926 return io_steal_work(req
);
5929 static inline struct file
*io_file_from_index(struct io_ring_ctx
*ctx
,
5932 struct fixed_file_table
*table
;
5934 table
= &ctx
->file_data
->table
[index
>> IORING_FILE_TABLE_SHIFT
];
5935 return table
->files
[index
& IORING_FILE_TABLE_MASK
];
5938 static int io_file_get(struct io_submit_state
*state
, struct io_kiocb
*req
,
5939 int fd
, struct file
**out_file
, bool fixed
)
5941 struct io_ring_ctx
*ctx
= req
->ctx
;
5945 if (unlikely(!ctx
->file_data
||
5946 (unsigned) fd
>= ctx
->nr_user_files
))
5948 fd
= array_index_nospec(fd
, ctx
->nr_user_files
);
5949 file
= io_file_from_index(ctx
, fd
);
5951 req
->fixed_file_refs
= ctx
->file_data
->cur_refs
;
5952 percpu_ref_get(req
->fixed_file_refs
);
5955 trace_io_uring_file_get(ctx
, fd
);
5956 file
= __io_file_get(state
, fd
);
5959 if (file
|| io_op_defs
[req
->opcode
].needs_file_no_error
) {
5966 static int io_req_set_file(struct io_submit_state
*state
, struct io_kiocb
*req
,
5971 fixed
= (req
->flags
& REQ_F_FIXED_FILE
) != 0;
5972 if (unlikely(!fixed
&& io_async_submit(req
->ctx
)))
5975 return io_file_get(state
, req
, fd
, &req
->file
, fixed
);
5978 static int io_grab_files(struct io_kiocb
*req
)
5981 struct io_ring_ctx
*ctx
= req
->ctx
;
5983 io_req_init_async(req
);
5985 if (req
->work
.files
|| (req
->flags
& REQ_F_NO_FILE_TABLE
))
5987 if (!ctx
->ring_file
)
5991 spin_lock_irq(&ctx
->inflight_lock
);
5993 * We use the f_ops->flush() handler to ensure that we can flush
5994 * out work accessing these files if the fd is closed. Check if
5995 * the fd has changed since we started down this path, and disallow
5996 * this operation if it has.
5998 if (fcheck(ctx
->ring_fd
) == ctx
->ring_file
) {
5999 list_add(&req
->inflight_entry
, &ctx
->inflight_list
);
6000 req
->flags
|= REQ_F_INFLIGHT
;
6001 req
->work
.files
= current
->files
;
6004 spin_unlock_irq(&ctx
->inflight_lock
);
6010 static inline int io_prep_work_files(struct io_kiocb
*req
)
6012 if (!io_op_defs
[req
->opcode
].file_table
)
6014 return io_grab_files(req
);
6017 static enum hrtimer_restart
io_link_timeout_fn(struct hrtimer
*timer
)
6019 struct io_timeout_data
*data
= container_of(timer
,
6020 struct io_timeout_data
, timer
);
6021 struct io_kiocb
*req
= data
->req
;
6022 struct io_ring_ctx
*ctx
= req
->ctx
;
6023 struct io_kiocb
*prev
= NULL
;
6024 unsigned long flags
;
6026 spin_lock_irqsave(&ctx
->completion_lock
, flags
);
6029 * We don't expect the list to be empty, that will only happen if we
6030 * race with the completion of the linked work.
6032 if (!list_empty(&req
->link_list
)) {
6033 prev
= list_entry(req
->link_list
.prev
, struct io_kiocb
,
6035 if (refcount_inc_not_zero(&prev
->refs
)) {
6036 list_del_init(&req
->link_list
);
6037 prev
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6042 spin_unlock_irqrestore(&ctx
->completion_lock
, flags
);
6045 req_set_fail_links(prev
);
6046 io_async_find_and_cancel(ctx
, req
, prev
->user_data
, -ETIME
);
6049 io_req_complete(req
, -ETIME
);
6051 return HRTIMER_NORESTART
;
6054 static void __io_queue_linked_timeout(struct io_kiocb
*req
)
6057 * If the list is now empty, then our linked request finished before
6058 * we got a chance to setup the timer
6060 if (!list_empty(&req
->link_list
)) {
6061 struct io_timeout_data
*data
= &req
->io
->timeout
;
6063 data
->timer
.function
= io_link_timeout_fn
;
6064 hrtimer_start(&data
->timer
, timespec64_to_ktime(data
->ts
),
6069 static void io_queue_linked_timeout(struct io_kiocb
*req
)
6071 struct io_ring_ctx
*ctx
= req
->ctx
;
6073 spin_lock_irq(&ctx
->completion_lock
);
6074 __io_queue_linked_timeout(req
);
6075 spin_unlock_irq(&ctx
->completion_lock
);
6077 /* drop submission reference */
6081 static struct io_kiocb
*io_prep_linked_timeout(struct io_kiocb
*req
)
6083 struct io_kiocb
*nxt
;
6085 if (!(req
->flags
& REQ_F_LINK_HEAD
))
6087 if (req
->flags
& REQ_F_LINK_TIMEOUT
)
6090 nxt
= list_first_entry_or_null(&req
->link_list
, struct io_kiocb
,
6092 if (!nxt
|| nxt
->opcode
!= IORING_OP_LINK_TIMEOUT
)
6095 req
->flags
|= REQ_F_LINK_TIMEOUT
;
6099 static void __io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6100 struct io_comp_state
*cs
)
6102 struct io_kiocb
*linked_timeout
;
6103 struct io_kiocb
*nxt
;
6104 const struct cred
*old_creds
= NULL
;
6108 linked_timeout
= io_prep_linked_timeout(req
);
6110 if ((req
->flags
& REQ_F_WORK_INITIALIZED
) && req
->work
.creds
&&
6111 req
->work
.creds
!= current_cred()) {
6113 revert_creds(old_creds
);
6114 if (old_creds
== req
->work
.creds
)
6115 old_creds
= NULL
; /* restored original creds */
6117 old_creds
= override_creds(req
->work
.creds
);
6120 ret
= io_issue_sqe(req
, sqe
, true, cs
);
6123 * We async punt it if the file wasn't marked NOWAIT, or if the file
6124 * doesn't support non-blocking read/write attempts
6126 if (ret
== -EAGAIN
&& !(req
->flags
& REQ_F_NOWAIT
)) {
6127 if (!io_arm_poll_handler(req
)) {
6129 ret
= io_prep_work_files(req
);
6133 * Queued up for async execution, worker will release
6134 * submit reference when the iocb is actually submitted.
6136 io_queue_async_work(req
);
6140 io_queue_linked_timeout(linked_timeout
);
6144 if (unlikely(ret
)) {
6146 /* un-prep timeout, so it'll be killed as any other linked */
6147 req
->flags
&= ~REQ_F_LINK_TIMEOUT
;
6148 req_set_fail_links(req
);
6150 io_req_complete(req
, ret
);
6154 /* drop submission reference */
6155 nxt
= io_put_req_find_next(req
);
6157 io_queue_linked_timeout(linked_timeout
);
6162 if (req
->flags
& REQ_F_FORCE_ASYNC
)
6168 revert_creds(old_creds
);
6171 static void io_queue_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6172 struct io_comp_state
*cs
)
6176 ret
= io_req_defer(req
, sqe
);
6178 if (ret
!= -EIOCBQUEUED
) {
6180 req_set_fail_links(req
);
6182 io_req_complete(req
, ret
);
6184 } else if (req
->flags
& REQ_F_FORCE_ASYNC
) {
6186 ret
= io_req_defer_prep(req
, sqe
);
6192 * Never try inline submit of IOSQE_ASYNC is set, go straight
6193 * to async execution.
6195 io_req_init_async(req
);
6196 req
->work
.flags
|= IO_WQ_WORK_CONCURRENT
;
6197 io_queue_async_work(req
);
6199 __io_queue_sqe(req
, sqe
, cs
);
6203 static inline void io_queue_link_head(struct io_kiocb
*req
,
6204 struct io_comp_state
*cs
)
6206 if (unlikely(req
->flags
& REQ_F_FAIL_LINK
)) {
6208 io_req_complete(req
, -ECANCELED
);
6210 io_queue_sqe(req
, NULL
, cs
);
6213 static int io_submit_sqe(struct io_kiocb
*req
, const struct io_uring_sqe
*sqe
,
6214 struct io_kiocb
**link
, struct io_comp_state
*cs
)
6216 struct io_ring_ctx
*ctx
= req
->ctx
;
6220 * If we already have a head request, queue this one for async
6221 * submittal once the head completes. If we don't have a head but
6222 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6223 * submitted sync once the chain is complete. If none of those
6224 * conditions are true (normal request), then just queue it.
6227 struct io_kiocb
*head
= *link
;
6230 * Taking sequential execution of a link, draining both sides
6231 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6232 * requests in the link. So, it drains the head and the
6233 * next after the link request. The last one is done via
6234 * drain_next flag to persist the effect across calls.
6236 if (req
->flags
& REQ_F_IO_DRAIN
) {
6237 head
->flags
|= REQ_F_IO_DRAIN
;
6238 ctx
->drain_next
= 1;
6240 ret
= io_req_defer_prep(req
, sqe
);
6241 if (unlikely(ret
)) {
6242 /* fail even hard links since we don't submit */
6243 head
->flags
|= REQ_F_FAIL_LINK
;
6246 trace_io_uring_link(ctx
, req
, head
);
6247 io_get_req_task(req
);
6248 list_add_tail(&req
->link_list
, &head
->link_list
);
6250 /* last request of a link, enqueue the link */
6251 if (!(req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
))) {
6252 io_queue_link_head(head
, cs
);
6256 if (unlikely(ctx
->drain_next
)) {
6257 req
->flags
|= REQ_F_IO_DRAIN
;
6258 ctx
->drain_next
= 0;
6260 if (req
->flags
& (REQ_F_LINK
| REQ_F_HARDLINK
)) {
6261 req
->flags
|= REQ_F_LINK_HEAD
;
6262 INIT_LIST_HEAD(&req
->link_list
);
6264 ret
= io_req_defer_prep(req
, sqe
);
6266 req
->flags
|= REQ_F_FAIL_LINK
;
6269 io_queue_sqe(req
, sqe
, cs
);
6277 * Batched submission is done, ensure local IO is flushed out.
6279 static void io_submit_state_end(struct io_submit_state
*state
)
6281 if (!list_empty(&state
->comp
.list
))
6282 io_submit_flush_completions(&state
->comp
);
6283 blk_finish_plug(&state
->plug
);
6284 io_state_file_put(state
);
6285 if (state
->free_reqs
)
6286 kmem_cache_free_bulk(req_cachep
, state
->free_reqs
, state
->reqs
);
6290 * Start submission side cache.
6292 static void io_submit_state_start(struct io_submit_state
*state
,
6293 struct io_ring_ctx
*ctx
, unsigned int max_ios
)
6295 blk_start_plug(&state
->plug
);
6297 state
->plug
.nowait
= true;
6300 INIT_LIST_HEAD(&state
->comp
.list
);
6301 state
->comp
.ctx
= ctx
;
6302 state
->free_reqs
= 0;
6304 state
->ios_left
= max_ios
;
6307 static void io_commit_sqring(struct io_ring_ctx
*ctx
)
6309 struct io_rings
*rings
= ctx
->rings
;
6312 * Ensure any loads from the SQEs are done at this point,
6313 * since once we write the new head, the application could
6314 * write new data to them.
6316 smp_store_release(&rings
->sq
.head
, ctx
->cached_sq_head
);
6320 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6321 * that is mapped by userspace. This means that care needs to be taken to
6322 * ensure that reads are stable, as we cannot rely on userspace always
6323 * being a good citizen. If members of the sqe are validated and then later
6324 * used, it's important that those reads are done through READ_ONCE() to
6325 * prevent a re-load down the line.
6327 static const struct io_uring_sqe
*io_get_sqe(struct io_ring_ctx
*ctx
)
6329 u32
*sq_array
= ctx
->sq_array
;
6333 * The cached sq head (or cq tail) serves two purposes:
6335 * 1) allows us to batch the cost of updating the user visible
6337 * 2) allows the kernel side to track the head on its own, even
6338 * though the application is the one updating it.
6340 head
= READ_ONCE(sq_array
[ctx
->cached_sq_head
& ctx
->sq_mask
]);
6341 if (likely(head
< ctx
->sq_entries
))
6342 return &ctx
->sq_sqes
[head
];
6344 /* drop invalid entries */
6345 ctx
->cached_sq_dropped
++;
6346 WRITE_ONCE(ctx
->rings
->sq_dropped
, ctx
->cached_sq_dropped
);
6350 static inline void io_consume_sqe(struct io_ring_ctx
*ctx
)
6352 ctx
->cached_sq_head
++;
6355 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
6356 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
6357 IOSQE_BUFFER_SELECT)
6359 static int io_init_req(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
,
6360 const struct io_uring_sqe
*sqe
,
6361 struct io_submit_state
*state
)
6363 unsigned int sqe_flags
;
6366 req
->opcode
= READ_ONCE(sqe
->opcode
);
6367 req
->user_data
= READ_ONCE(sqe
->user_data
);
6372 /* one is dropped after submission, the other at completion */
6373 refcount_set(&req
->refs
, 2);
6374 req
->task
= current
;
6377 if (unlikely(req
->opcode
>= IORING_OP_LAST
))
6380 if (unlikely(io_sq_thread_acquire_mm(ctx
, req
)))
6383 sqe_flags
= READ_ONCE(sqe
->flags
);
6384 /* enforce forwards compatibility on users */
6385 if (unlikely(sqe_flags
& ~SQE_VALID_FLAGS
))
6388 if ((sqe_flags
& IOSQE_BUFFER_SELECT
) &&
6389 !io_op_defs
[req
->opcode
].buffer_select
)
6392 id
= READ_ONCE(sqe
->personality
);
6394 io_req_init_async(req
);
6395 req
->work
.creds
= idr_find(&ctx
->personality_idr
, id
);
6396 if (unlikely(!req
->work
.creds
))
6398 get_cred(req
->work
.creds
);
6401 /* same numerical values with corresponding REQ_F_*, safe to copy */
6402 req
->flags
|= sqe_flags
;
6404 if (!io_op_defs
[req
->opcode
].needs_file
)
6407 return io_req_set_file(state
, req
, READ_ONCE(sqe
->fd
));
6410 static int io_submit_sqes(struct io_ring_ctx
*ctx
, unsigned int nr
,
6411 struct file
*ring_file
, int ring_fd
)
6413 struct io_submit_state state
;
6414 struct io_kiocb
*link
= NULL
;
6415 int i
, submitted
= 0;
6417 /* if we have a backlog and couldn't flush it all, return BUSY */
6418 if (test_bit(0, &ctx
->sq_check_overflow
)) {
6419 if (!list_empty(&ctx
->cq_overflow_list
) &&
6420 !io_cqring_overflow_flush(ctx
, false))
6424 /* make sure SQ entry isn't read before tail */
6425 nr
= min3(nr
, ctx
->sq_entries
, io_sqring_entries(ctx
));
6427 if (!percpu_ref_tryget_many(&ctx
->refs
, nr
))
6430 io_submit_state_start(&state
, ctx
, nr
);
6432 ctx
->ring_fd
= ring_fd
;
6433 ctx
->ring_file
= ring_file
;
6435 for (i
= 0; i
< nr
; i
++) {
6436 const struct io_uring_sqe
*sqe
;
6437 struct io_kiocb
*req
;
6440 sqe
= io_get_sqe(ctx
);
6441 if (unlikely(!sqe
)) {
6442 io_consume_sqe(ctx
);
6445 req
= io_alloc_req(ctx
, &state
);
6446 if (unlikely(!req
)) {
6448 submitted
= -EAGAIN
;
6452 err
= io_init_req(ctx
, req
, sqe
, &state
);
6453 io_consume_sqe(ctx
);
6454 /* will complete beyond this point, count as submitted */
6457 if (unlikely(err
)) {
6460 io_req_complete(req
, err
);
6464 trace_io_uring_submit_sqe(ctx
, req
->opcode
, req
->user_data
,
6465 true, io_async_submit(ctx
));
6466 err
= io_submit_sqe(req
, sqe
, &link
, &state
.comp
);
6471 if (unlikely(submitted
!= nr
)) {
6472 int ref_used
= (submitted
== -EAGAIN
) ? 0 : submitted
;
6474 percpu_ref_put_many(&ctx
->refs
, nr
- ref_used
);
6477 io_queue_link_head(link
, &state
.comp
);
6478 io_submit_state_end(&state
);
6480 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6481 io_commit_sqring(ctx
);
6486 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx
*ctx
)
6488 /* Tell userspace we may need a wakeup call */
6489 spin_lock_irq(&ctx
->completion_lock
);
6490 ctx
->rings
->sq_flags
|= IORING_SQ_NEED_WAKEUP
;
6491 spin_unlock_irq(&ctx
->completion_lock
);
6494 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx
*ctx
)
6496 spin_lock_irq(&ctx
->completion_lock
);
6497 ctx
->rings
->sq_flags
&= ~IORING_SQ_NEED_WAKEUP
;
6498 spin_unlock_irq(&ctx
->completion_lock
);
6501 static int io_sq_thread(void *data
)
6503 struct io_ring_ctx
*ctx
= data
;
6504 const struct cred
*old_cred
;
6506 unsigned long timeout
;
6509 complete(&ctx
->sq_thread_comp
);
6511 old_cred
= override_creds(ctx
->creds
);
6513 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6514 while (!kthread_should_park()) {
6515 unsigned int to_submit
;
6517 if (!list_empty(&ctx
->iopoll_list
)) {
6518 unsigned nr_events
= 0;
6520 mutex_lock(&ctx
->uring_lock
);
6521 if (!list_empty(&ctx
->iopoll_list
) && !need_resched())
6522 io_do_iopoll(ctx
, &nr_events
, 0);
6524 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6525 mutex_unlock(&ctx
->uring_lock
);
6528 to_submit
= io_sqring_entries(ctx
);
6531 * If submit got -EBUSY, flag us as needing the application
6532 * to enter the kernel to reap and flush events.
6534 if (!to_submit
|| ret
== -EBUSY
|| need_resched()) {
6536 * Drop cur_mm before scheduling, we can't hold it for
6537 * long periods (or over schedule()). Do this before
6538 * adding ourselves to the waitqueue, as the unuse/drop
6541 io_sq_thread_drop_mm();
6544 * We're polling. If we're within the defined idle
6545 * period, then let us spin without work before going
6546 * to sleep. The exception is if we got EBUSY doing
6547 * more IO, we should wait for the application to
6548 * reap events and wake us up.
6550 if (!list_empty(&ctx
->iopoll_list
) || need_resched() ||
6551 (!time_after(jiffies
, timeout
) && ret
!= -EBUSY
&&
6552 !percpu_ref_is_dying(&ctx
->refs
))) {
6558 prepare_to_wait(&ctx
->sqo_wait
, &wait
,
6559 TASK_INTERRUPTIBLE
);
6562 * While doing polled IO, before going to sleep, we need
6563 * to check if there are new reqs added to iopoll_list,
6564 * it is because reqs may have been punted to io worker
6565 * and will be added to iopoll_list later, hence check
6566 * the iopoll_list again.
6568 if ((ctx
->flags
& IORING_SETUP_IOPOLL
) &&
6569 !list_empty_careful(&ctx
->iopoll_list
)) {
6570 finish_wait(&ctx
->sqo_wait
, &wait
);
6574 io_ring_set_wakeup_flag(ctx
);
6576 to_submit
= io_sqring_entries(ctx
);
6577 if (!to_submit
|| ret
== -EBUSY
) {
6578 if (kthread_should_park()) {
6579 finish_wait(&ctx
->sqo_wait
, &wait
);
6582 if (io_run_task_work()) {
6583 finish_wait(&ctx
->sqo_wait
, &wait
);
6584 io_ring_clear_wakeup_flag(ctx
);
6587 if (signal_pending(current
))
6588 flush_signals(current
);
6590 finish_wait(&ctx
->sqo_wait
, &wait
);
6592 io_ring_clear_wakeup_flag(ctx
);
6596 finish_wait(&ctx
->sqo_wait
, &wait
);
6598 io_ring_clear_wakeup_flag(ctx
);
6601 mutex_lock(&ctx
->uring_lock
);
6602 if (likely(!percpu_ref_is_dying(&ctx
->refs
)))
6603 ret
= io_submit_sqes(ctx
, to_submit
, NULL
, -1);
6604 mutex_unlock(&ctx
->uring_lock
);
6605 timeout
= jiffies
+ ctx
->sq_thread_idle
;
6610 io_sq_thread_drop_mm();
6611 revert_creds(old_cred
);
6618 struct io_wait_queue
{
6619 struct wait_queue_entry wq
;
6620 struct io_ring_ctx
*ctx
;
6622 unsigned nr_timeouts
;
6625 static inline bool io_should_wake(struct io_wait_queue
*iowq
, bool noflush
)
6627 struct io_ring_ctx
*ctx
= iowq
->ctx
;
6630 * Wake up if we have enough events, or if a timeout occurred since we
6631 * started waiting. For timeouts, we always want to return to userspace,
6632 * regardless of event count.
6634 return io_cqring_events(ctx
, noflush
) >= iowq
->to_wait
||
6635 atomic_read(&ctx
->cq_timeouts
) != iowq
->nr_timeouts
;
6638 static int io_wake_function(struct wait_queue_entry
*curr
, unsigned int mode
,
6639 int wake_flags
, void *key
)
6641 struct io_wait_queue
*iowq
= container_of(curr
, struct io_wait_queue
,
6644 /* use noflush == true, as we can't safely rely on locking context */
6645 if (!io_should_wake(iowq
, true))
6648 return autoremove_wake_function(curr
, mode
, wake_flags
, key
);
6652 * Wait until events become available, if we don't already have some. The
6653 * application must reap them itself, as they reside on the shared cq ring.
6655 static int io_cqring_wait(struct io_ring_ctx
*ctx
, int min_events
,
6656 const sigset_t __user
*sig
, size_t sigsz
)
6658 struct io_wait_queue iowq
= {
6661 .func
= io_wake_function
,
6662 .entry
= LIST_HEAD_INIT(iowq
.wq
.entry
),
6665 .to_wait
= min_events
,
6667 struct io_rings
*rings
= ctx
->rings
;
6671 if (io_cqring_events(ctx
, false) >= min_events
)
6673 if (!io_run_task_work())
6678 #ifdef CONFIG_COMPAT
6679 if (in_compat_syscall())
6680 ret
= set_compat_user_sigmask((const compat_sigset_t __user
*)sig
,
6684 ret
= set_user_sigmask(sig
, sigsz
);
6690 iowq
.nr_timeouts
= atomic_read(&ctx
->cq_timeouts
);
6691 trace_io_uring_cqring_wait(ctx
, min_events
);
6693 prepare_to_wait_exclusive(&ctx
->wait
, &iowq
.wq
,
6694 TASK_INTERRUPTIBLE
);
6695 /* make sure we run task_work before checking for signals */
6696 if (io_run_task_work())
6698 if (signal_pending(current
)) {
6699 if (current
->jobctl
& JOBCTL_TASK_WORK
) {
6700 spin_lock_irq(¤t
->sighand
->siglock
);
6701 current
->jobctl
&= ~JOBCTL_TASK_WORK
;
6702 recalc_sigpending();
6703 spin_unlock_irq(¤t
->sighand
->siglock
);
6709 if (io_should_wake(&iowq
, false))
6713 finish_wait(&ctx
->wait
, &iowq
.wq
);
6715 restore_saved_sigmask_unless(ret
== -EINTR
);
6717 return READ_ONCE(rings
->cq
.head
) == READ_ONCE(rings
->cq
.tail
) ? ret
: 0;
6720 static void __io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6722 #if defined(CONFIG_UNIX)
6723 if (ctx
->ring_sock
) {
6724 struct sock
*sock
= ctx
->ring_sock
->sk
;
6725 struct sk_buff
*skb
;
6727 while ((skb
= skb_dequeue(&sock
->sk_receive_queue
)) != NULL
)
6733 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
6736 file
= io_file_from_index(ctx
, i
);
6743 static void io_file_ref_kill(struct percpu_ref
*ref
)
6745 struct fixed_file_data
*data
;
6747 data
= container_of(ref
, struct fixed_file_data
, refs
);
6748 complete(&data
->done
);
6751 static int io_sqe_files_unregister(struct io_ring_ctx
*ctx
)
6753 struct fixed_file_data
*data
= ctx
->file_data
;
6754 struct fixed_file_ref_node
*ref_node
= NULL
;
6755 unsigned nr_tables
, i
;
6760 spin_lock(&data
->lock
);
6761 if (!list_empty(&data
->ref_list
))
6762 ref_node
= list_first_entry(&data
->ref_list
,
6763 struct fixed_file_ref_node
, node
);
6764 spin_unlock(&data
->lock
);
6766 percpu_ref_kill(&ref_node
->refs
);
6768 percpu_ref_kill(&data
->refs
);
6770 /* wait for all refs nodes to complete */
6771 flush_delayed_work(&ctx
->file_put_work
);
6772 wait_for_completion(&data
->done
);
6774 __io_sqe_files_unregister(ctx
);
6775 nr_tables
= DIV_ROUND_UP(ctx
->nr_user_files
, IORING_MAX_FILES_TABLE
);
6776 for (i
= 0; i
< nr_tables
; i
++)
6777 kfree(data
->table
[i
].files
);
6779 percpu_ref_exit(&data
->refs
);
6781 ctx
->file_data
= NULL
;
6782 ctx
->nr_user_files
= 0;
6786 static void io_sq_thread_stop(struct io_ring_ctx
*ctx
)
6788 if (ctx
->sqo_thread
) {
6789 wait_for_completion(&ctx
->sq_thread_comp
);
6791 * The park is a bit of a work-around, without it we get
6792 * warning spews on shutdown with SQPOLL set and affinity
6793 * set to a single CPU.
6795 kthread_park(ctx
->sqo_thread
);
6796 kthread_stop(ctx
->sqo_thread
);
6797 ctx
->sqo_thread
= NULL
;
6801 static void io_finish_async(struct io_ring_ctx
*ctx
)
6803 io_sq_thread_stop(ctx
);
6806 io_wq_destroy(ctx
->io_wq
);
6811 #if defined(CONFIG_UNIX)
6813 * Ensure the UNIX gc is aware of our file set, so we are certain that
6814 * the io_uring can be safely unregistered on process exit, even if we have
6815 * loops in the file referencing.
6817 static int __io_sqe_files_scm(struct io_ring_ctx
*ctx
, int nr
, int offset
)
6819 struct sock
*sk
= ctx
->ring_sock
->sk
;
6820 struct scm_fp_list
*fpl
;
6821 struct sk_buff
*skb
;
6824 fpl
= kzalloc(sizeof(*fpl
), GFP_KERNEL
);
6828 skb
= alloc_skb(0, GFP_KERNEL
);
6837 fpl
->user
= get_uid(ctx
->user
);
6838 for (i
= 0; i
< nr
; i
++) {
6839 struct file
*file
= io_file_from_index(ctx
, i
+ offset
);
6843 fpl
->fp
[nr_files
] = get_file(file
);
6844 unix_inflight(fpl
->user
, fpl
->fp
[nr_files
]);
6849 fpl
->max
= SCM_MAX_FD
;
6850 fpl
->count
= nr_files
;
6851 UNIXCB(skb
).fp
= fpl
;
6852 skb
->destructor
= unix_destruct_scm
;
6853 refcount_add(skb
->truesize
, &sk
->sk_wmem_alloc
);
6854 skb_queue_head(&sk
->sk_receive_queue
, skb
);
6856 for (i
= 0; i
< nr_files
; i
++)
6867 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
6868 * causes regular reference counting to break down. We rely on the UNIX
6869 * garbage collection to take care of this problem for us.
6871 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6873 unsigned left
, total
;
6877 left
= ctx
->nr_user_files
;
6879 unsigned this_files
= min_t(unsigned, left
, SCM_MAX_FD
);
6881 ret
= __io_sqe_files_scm(ctx
, this_files
, total
);
6885 total
+= this_files
;
6891 while (total
< ctx
->nr_user_files
) {
6892 struct file
*file
= io_file_from_index(ctx
, total
);
6902 static int io_sqe_files_scm(struct io_ring_ctx
*ctx
)
6908 static int io_sqe_alloc_file_tables(struct io_ring_ctx
*ctx
, unsigned nr_tables
,
6913 for (i
= 0; i
< nr_tables
; i
++) {
6914 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6915 unsigned this_files
;
6917 this_files
= min(nr_files
, IORING_MAX_FILES_TABLE
);
6918 table
->files
= kcalloc(this_files
, sizeof(struct file
*),
6922 nr_files
-= this_files
;
6928 for (i
= 0; i
< nr_tables
; i
++) {
6929 struct fixed_file_table
*table
= &ctx
->file_data
->table
[i
];
6930 kfree(table
->files
);
6935 static void io_ring_file_put(struct io_ring_ctx
*ctx
, struct file
*file
)
6937 #if defined(CONFIG_UNIX)
6938 struct sock
*sock
= ctx
->ring_sock
->sk
;
6939 struct sk_buff_head list
, *head
= &sock
->sk_receive_queue
;
6940 struct sk_buff
*skb
;
6943 __skb_queue_head_init(&list
);
6946 * Find the skb that holds this file in its SCM_RIGHTS. When found,
6947 * remove this entry and rearrange the file array.
6949 skb
= skb_dequeue(head
);
6951 struct scm_fp_list
*fp
;
6953 fp
= UNIXCB(skb
).fp
;
6954 for (i
= 0; i
< fp
->count
; i
++) {
6957 if (fp
->fp
[i
] != file
)
6960 unix_notinflight(fp
->user
, fp
->fp
[i
]);
6961 left
= fp
->count
- 1 - i
;
6963 memmove(&fp
->fp
[i
], &fp
->fp
[i
+ 1],
6964 left
* sizeof(struct file
*));
6971 __skb_queue_tail(&list
, skb
);
6981 __skb_queue_tail(&list
, skb
);
6983 skb
= skb_dequeue(head
);
6986 if (skb_peek(&list
)) {
6987 spin_lock_irq(&head
->lock
);
6988 while ((skb
= __skb_dequeue(&list
)) != NULL
)
6989 __skb_queue_tail(head
, skb
);
6990 spin_unlock_irq(&head
->lock
);
6997 struct io_file_put
{
6998 struct list_head list
;
7002 static void __io_file_put_work(struct fixed_file_ref_node
*ref_node
)
7004 struct fixed_file_data
*file_data
= ref_node
->file_data
;
7005 struct io_ring_ctx
*ctx
= file_data
->ctx
;
7006 struct io_file_put
*pfile
, *tmp
;
7008 list_for_each_entry_safe(pfile
, tmp
, &ref_node
->file_list
, list
) {
7009 list_del(&pfile
->list
);
7010 io_ring_file_put(ctx
, pfile
->file
);
7014 spin_lock(&file_data
->lock
);
7015 list_del(&ref_node
->node
);
7016 spin_unlock(&file_data
->lock
);
7018 percpu_ref_exit(&ref_node
->refs
);
7020 percpu_ref_put(&file_data
->refs
);
7023 static void io_file_put_work(struct work_struct
*work
)
7025 struct io_ring_ctx
*ctx
;
7026 struct llist_node
*node
;
7028 ctx
= container_of(work
, struct io_ring_ctx
, file_put_work
.work
);
7029 node
= llist_del_all(&ctx
->file_put_llist
);
7032 struct fixed_file_ref_node
*ref_node
;
7033 struct llist_node
*next
= node
->next
;
7035 ref_node
= llist_entry(node
, struct fixed_file_ref_node
, llist
);
7036 __io_file_put_work(ref_node
);
7041 static void io_file_data_ref_zero(struct percpu_ref
*ref
)
7043 struct fixed_file_ref_node
*ref_node
;
7044 struct io_ring_ctx
*ctx
;
7048 ref_node
= container_of(ref
, struct fixed_file_ref_node
, refs
);
7049 ctx
= ref_node
->file_data
->ctx
;
7051 if (percpu_ref_is_dying(&ctx
->file_data
->refs
))
7054 first_add
= llist_add(&ref_node
->llist
, &ctx
->file_put_llist
);
7056 mod_delayed_work(system_wq
, &ctx
->file_put_work
, 0);
7058 queue_delayed_work(system_wq
, &ctx
->file_put_work
, delay
);
7061 static struct fixed_file_ref_node
*alloc_fixed_file_ref_node(
7062 struct io_ring_ctx
*ctx
)
7064 struct fixed_file_ref_node
*ref_node
;
7066 ref_node
= kzalloc(sizeof(*ref_node
), GFP_KERNEL
);
7068 return ERR_PTR(-ENOMEM
);
7070 if (percpu_ref_init(&ref_node
->refs
, io_file_data_ref_zero
,
7073 return ERR_PTR(-ENOMEM
);
7075 INIT_LIST_HEAD(&ref_node
->node
);
7076 INIT_LIST_HEAD(&ref_node
->file_list
);
7077 ref_node
->file_data
= ctx
->file_data
;
7081 static void destroy_fixed_file_ref_node(struct fixed_file_ref_node
*ref_node
)
7083 percpu_ref_exit(&ref_node
->refs
);
7087 static int io_sqe_files_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7090 __s32 __user
*fds
= (__s32 __user
*) arg
;
7095 struct fixed_file_ref_node
*ref_node
;
7101 if (nr_args
> IORING_MAX_FIXED_FILES
)
7104 ctx
->file_data
= kzalloc(sizeof(*ctx
->file_data
), GFP_KERNEL
);
7105 if (!ctx
->file_data
)
7107 ctx
->file_data
->ctx
= ctx
;
7108 init_completion(&ctx
->file_data
->done
);
7109 INIT_LIST_HEAD(&ctx
->file_data
->ref_list
);
7110 spin_lock_init(&ctx
->file_data
->lock
);
7112 nr_tables
= DIV_ROUND_UP(nr_args
, IORING_MAX_FILES_TABLE
);
7113 ctx
->file_data
->table
= kcalloc(nr_tables
,
7114 sizeof(struct fixed_file_table
),
7116 if (!ctx
->file_data
->table
) {
7117 kfree(ctx
->file_data
);
7118 ctx
->file_data
= NULL
;
7122 if (percpu_ref_init(&ctx
->file_data
->refs
, io_file_ref_kill
,
7123 PERCPU_REF_ALLOW_REINIT
, GFP_KERNEL
)) {
7124 kfree(ctx
->file_data
->table
);
7125 kfree(ctx
->file_data
);
7126 ctx
->file_data
= NULL
;
7130 if (io_sqe_alloc_file_tables(ctx
, nr_tables
, nr_args
)) {
7131 percpu_ref_exit(&ctx
->file_data
->refs
);
7132 kfree(ctx
->file_data
->table
);
7133 kfree(ctx
->file_data
);
7134 ctx
->file_data
= NULL
;
7138 for (i
= 0; i
< nr_args
; i
++, ctx
->nr_user_files
++) {
7139 struct fixed_file_table
*table
;
7143 if (copy_from_user(&fd
, &fds
[i
], sizeof(fd
)))
7145 /* allow sparse sets */
7151 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7152 index
= i
& IORING_FILE_TABLE_MASK
;
7160 * Don't allow io_uring instances to be registered. If UNIX
7161 * isn't enabled, then this causes a reference cycle and this
7162 * instance can never get freed. If UNIX is enabled we'll
7163 * handle it just fine, but there's still no point in allowing
7164 * a ring fd as it doesn't support regular read/write anyway.
7166 if (file
->f_op
== &io_uring_fops
) {
7171 table
->files
[index
] = file
;
7175 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
7176 file
= io_file_from_index(ctx
, i
);
7180 for (i
= 0; i
< nr_tables
; i
++)
7181 kfree(ctx
->file_data
->table
[i
].files
);
7183 percpu_ref_exit(&ctx
->file_data
->refs
);
7184 kfree(ctx
->file_data
->table
);
7185 kfree(ctx
->file_data
);
7186 ctx
->file_data
= NULL
;
7187 ctx
->nr_user_files
= 0;
7191 ret
= io_sqe_files_scm(ctx
);
7193 io_sqe_files_unregister(ctx
);
7197 ref_node
= alloc_fixed_file_ref_node(ctx
);
7198 if (IS_ERR(ref_node
)) {
7199 io_sqe_files_unregister(ctx
);
7200 return PTR_ERR(ref_node
);
7203 ctx
->file_data
->cur_refs
= &ref_node
->refs
;
7204 spin_lock(&ctx
->file_data
->lock
);
7205 list_add(&ref_node
->node
, &ctx
->file_data
->ref_list
);
7206 spin_unlock(&ctx
->file_data
->lock
);
7207 percpu_ref_get(&ctx
->file_data
->refs
);
7211 static int io_sqe_file_register(struct io_ring_ctx
*ctx
, struct file
*file
,
7214 #if defined(CONFIG_UNIX)
7215 struct sock
*sock
= ctx
->ring_sock
->sk
;
7216 struct sk_buff_head
*head
= &sock
->sk_receive_queue
;
7217 struct sk_buff
*skb
;
7220 * See if we can merge this file into an existing skb SCM_RIGHTS
7221 * file set. If there's no room, fall back to allocating a new skb
7222 * and filling it in.
7224 spin_lock_irq(&head
->lock
);
7225 skb
= skb_peek(head
);
7227 struct scm_fp_list
*fpl
= UNIXCB(skb
).fp
;
7229 if (fpl
->count
< SCM_MAX_FD
) {
7230 __skb_unlink(skb
, head
);
7231 spin_unlock_irq(&head
->lock
);
7232 fpl
->fp
[fpl
->count
] = get_file(file
);
7233 unix_inflight(fpl
->user
, fpl
->fp
[fpl
->count
]);
7235 spin_lock_irq(&head
->lock
);
7236 __skb_queue_head(head
, skb
);
7241 spin_unlock_irq(&head
->lock
);
7248 return __io_sqe_files_scm(ctx
, 1, index
);
7254 static int io_queue_file_removal(struct fixed_file_data
*data
,
7257 struct io_file_put
*pfile
;
7258 struct percpu_ref
*refs
= data
->cur_refs
;
7259 struct fixed_file_ref_node
*ref_node
;
7261 pfile
= kzalloc(sizeof(*pfile
), GFP_KERNEL
);
7265 ref_node
= container_of(refs
, struct fixed_file_ref_node
, refs
);
7267 list_add(&pfile
->list
, &ref_node
->file_list
);
7272 static int __io_sqe_files_update(struct io_ring_ctx
*ctx
,
7273 struct io_uring_files_update
*up
,
7276 struct fixed_file_data
*data
= ctx
->file_data
;
7277 struct fixed_file_ref_node
*ref_node
;
7282 bool needs_switch
= false;
7284 if (check_add_overflow(up
->offset
, nr_args
, &done
))
7286 if (done
> ctx
->nr_user_files
)
7289 ref_node
= alloc_fixed_file_ref_node(ctx
);
7290 if (IS_ERR(ref_node
))
7291 return PTR_ERR(ref_node
);
7294 fds
= u64_to_user_ptr(up
->fds
);
7296 struct fixed_file_table
*table
;
7300 if (copy_from_user(&fd
, &fds
[done
], sizeof(fd
))) {
7304 i
= array_index_nospec(up
->offset
, ctx
->nr_user_files
);
7305 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
7306 index
= i
& IORING_FILE_TABLE_MASK
;
7307 if (table
->files
[index
]) {
7308 file
= io_file_from_index(ctx
, index
);
7309 err
= io_queue_file_removal(data
, file
);
7312 table
->files
[index
] = NULL
;
7313 needs_switch
= true;
7322 * Don't allow io_uring instances to be registered. If
7323 * UNIX isn't enabled, then this causes a reference
7324 * cycle and this instance can never get freed. If UNIX
7325 * is enabled we'll handle it just fine, but there's
7326 * still no point in allowing a ring fd as it doesn't
7327 * support regular read/write anyway.
7329 if (file
->f_op
== &io_uring_fops
) {
7334 table
->files
[index
] = file
;
7335 err
= io_sqe_file_register(ctx
, file
, i
);
7347 percpu_ref_kill(data
->cur_refs
);
7348 spin_lock(&data
->lock
);
7349 list_add(&ref_node
->node
, &data
->ref_list
);
7350 data
->cur_refs
= &ref_node
->refs
;
7351 spin_unlock(&data
->lock
);
7352 percpu_ref_get(&ctx
->file_data
->refs
);
7354 destroy_fixed_file_ref_node(ref_node
);
7356 return done
? done
: err
;
7359 static int io_sqe_files_update(struct io_ring_ctx
*ctx
, void __user
*arg
,
7362 struct io_uring_files_update up
;
7364 if (!ctx
->file_data
)
7368 if (copy_from_user(&up
, arg
, sizeof(up
)))
7373 return __io_sqe_files_update(ctx
, &up
, nr_args
);
7376 static void io_free_work(struct io_wq_work
*work
)
7378 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
7380 /* Consider that io_steal_work() relies on this ref */
7384 static int io_init_wq_offload(struct io_ring_ctx
*ctx
,
7385 struct io_uring_params
*p
)
7387 struct io_wq_data data
;
7389 struct io_ring_ctx
*ctx_attach
;
7390 unsigned int concurrency
;
7393 data
.user
= ctx
->user
;
7394 data
.free_work
= io_free_work
;
7395 data
.do_work
= io_wq_submit_work
;
7397 if (!(p
->flags
& IORING_SETUP_ATTACH_WQ
)) {
7398 /* Do QD, or 4 * CPUS, whatever is smallest */
7399 concurrency
= min(ctx
->sq_entries
, 4 * num_online_cpus());
7401 ctx
->io_wq
= io_wq_create(concurrency
, &data
);
7402 if (IS_ERR(ctx
->io_wq
)) {
7403 ret
= PTR_ERR(ctx
->io_wq
);
7409 f
= fdget(p
->wq_fd
);
7413 if (f
.file
->f_op
!= &io_uring_fops
) {
7418 ctx_attach
= f
.file
->private_data
;
7419 /* @io_wq is protected by holding the fd */
7420 if (!io_wq_get(ctx_attach
->io_wq
, &data
)) {
7425 ctx
->io_wq
= ctx_attach
->io_wq
;
7431 static int io_sq_offload_start(struct io_ring_ctx
*ctx
,
7432 struct io_uring_params
*p
)
7436 mmgrab(current
->mm
);
7437 ctx
->sqo_mm
= current
->mm
;
7439 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
7441 if (!capable(CAP_SYS_ADMIN
))
7444 ctx
->sq_thread_idle
= msecs_to_jiffies(p
->sq_thread_idle
);
7445 if (!ctx
->sq_thread_idle
)
7446 ctx
->sq_thread_idle
= HZ
;
7448 if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7449 int cpu
= p
->sq_thread_cpu
;
7452 if (cpu
>= nr_cpu_ids
)
7454 if (!cpu_online(cpu
))
7457 ctx
->sqo_thread
= kthread_create_on_cpu(io_sq_thread
,
7461 ctx
->sqo_thread
= kthread_create(io_sq_thread
, ctx
,
7464 if (IS_ERR(ctx
->sqo_thread
)) {
7465 ret
= PTR_ERR(ctx
->sqo_thread
);
7466 ctx
->sqo_thread
= NULL
;
7469 wake_up_process(ctx
->sqo_thread
);
7470 } else if (p
->flags
& IORING_SETUP_SQ_AFF
) {
7471 /* Can't have SQ_AFF without SQPOLL */
7476 ret
= io_init_wq_offload(ctx
, p
);
7482 io_finish_async(ctx
);
7484 mmdrop(ctx
->sqo_mm
);
7490 static inline void __io_unaccount_mem(struct user_struct
*user
,
7491 unsigned long nr_pages
)
7493 atomic_long_sub(nr_pages
, &user
->locked_vm
);
7496 static inline int __io_account_mem(struct user_struct
*user
,
7497 unsigned long nr_pages
)
7499 unsigned long page_limit
, cur_pages
, new_pages
;
7501 /* Don't allow more pages than we can safely lock */
7502 page_limit
= rlimit(RLIMIT_MEMLOCK
) >> PAGE_SHIFT
;
7505 cur_pages
= atomic_long_read(&user
->locked_vm
);
7506 new_pages
= cur_pages
+ nr_pages
;
7507 if (new_pages
> page_limit
)
7509 } while (atomic_long_cmpxchg(&user
->locked_vm
, cur_pages
,
7510 new_pages
) != cur_pages
);
7515 static void io_unaccount_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7516 enum io_mem_account acct
)
7519 __io_unaccount_mem(ctx
->user
, nr_pages
);
7522 if (acct
== ACCT_LOCKED
)
7523 ctx
->sqo_mm
->locked_vm
-= nr_pages
;
7524 else if (acct
== ACCT_PINNED
)
7525 atomic64_sub(nr_pages
, &ctx
->sqo_mm
->pinned_vm
);
7529 static int io_account_mem(struct io_ring_ctx
*ctx
, unsigned long nr_pages
,
7530 enum io_mem_account acct
)
7534 if (ctx
->limit_mem
) {
7535 ret
= __io_account_mem(ctx
->user
, nr_pages
);
7541 if (acct
== ACCT_LOCKED
)
7542 ctx
->sqo_mm
->locked_vm
+= nr_pages
;
7543 else if (acct
== ACCT_PINNED
)
7544 atomic64_add(nr_pages
, &ctx
->sqo_mm
->pinned_vm
);
7550 static void io_mem_free(void *ptr
)
7557 page
= virt_to_head_page(ptr
);
7558 if (put_page_testzero(page
))
7559 free_compound_page(page
);
7562 static void *io_mem_alloc(size_t size
)
7564 gfp_t gfp_flags
= GFP_KERNEL
| __GFP_ZERO
| __GFP_NOWARN
| __GFP_COMP
|
7567 return (void *) __get_free_pages(gfp_flags
, get_order(size
));
7570 static unsigned long rings_size(unsigned sq_entries
, unsigned cq_entries
,
7573 struct io_rings
*rings
;
7574 size_t off
, sq_array_size
;
7576 off
= struct_size(rings
, cqes
, cq_entries
);
7577 if (off
== SIZE_MAX
)
7581 off
= ALIGN(off
, SMP_CACHE_BYTES
);
7589 sq_array_size
= array_size(sizeof(u32
), sq_entries
);
7590 if (sq_array_size
== SIZE_MAX
)
7593 if (check_add_overflow(off
, sq_array_size
, &off
))
7599 static unsigned long ring_pages(unsigned sq_entries
, unsigned cq_entries
)
7603 pages
= (size_t)1 << get_order(
7604 rings_size(sq_entries
, cq_entries
, NULL
));
7605 pages
+= (size_t)1 << get_order(
7606 array_size(sizeof(struct io_uring_sqe
), sq_entries
));
7611 static int io_sqe_buffer_unregister(struct io_ring_ctx
*ctx
)
7615 if (!ctx
->user_bufs
)
7618 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
7619 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7621 for (j
= 0; j
< imu
->nr_bvecs
; j
++)
7622 unpin_user_page(imu
->bvec
[j
].bv_page
);
7624 io_unaccount_mem(ctx
, imu
->nr_bvecs
, ACCT_PINNED
);
7629 kfree(ctx
->user_bufs
);
7630 ctx
->user_bufs
= NULL
;
7631 ctx
->nr_user_bufs
= 0;
7635 static int io_copy_iov(struct io_ring_ctx
*ctx
, struct iovec
*dst
,
7636 void __user
*arg
, unsigned index
)
7638 struct iovec __user
*src
;
7640 #ifdef CONFIG_COMPAT
7642 struct compat_iovec __user
*ciovs
;
7643 struct compat_iovec ciov
;
7645 ciovs
= (struct compat_iovec __user
*) arg
;
7646 if (copy_from_user(&ciov
, &ciovs
[index
], sizeof(ciov
)))
7649 dst
->iov_base
= u64_to_user_ptr((u64
)ciov
.iov_base
);
7650 dst
->iov_len
= ciov
.iov_len
;
7654 src
= (struct iovec __user
*) arg
;
7655 if (copy_from_user(dst
, &src
[index
], sizeof(*dst
)))
7660 static int io_sqe_buffer_register(struct io_ring_ctx
*ctx
, void __user
*arg
,
7663 struct vm_area_struct
**vmas
= NULL
;
7664 struct page
**pages
= NULL
;
7665 int i
, j
, got_pages
= 0;
7670 if (!nr_args
|| nr_args
> UIO_MAXIOV
)
7673 ctx
->user_bufs
= kcalloc(nr_args
, sizeof(struct io_mapped_ubuf
),
7675 if (!ctx
->user_bufs
)
7678 for (i
= 0; i
< nr_args
; i
++) {
7679 struct io_mapped_ubuf
*imu
= &ctx
->user_bufs
[i
];
7680 unsigned long off
, start
, end
, ubuf
;
7685 ret
= io_copy_iov(ctx
, &iov
, arg
, i
);
7690 * Don't impose further limits on the size and buffer
7691 * constraints here, we'll -EINVAL later when IO is
7692 * submitted if they are wrong.
7695 if (!iov
.iov_base
|| !iov
.iov_len
)
7698 /* arbitrary limit, but we need something */
7699 if (iov
.iov_len
> SZ_1G
)
7702 ubuf
= (unsigned long) iov
.iov_base
;
7703 end
= (ubuf
+ iov
.iov_len
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
7704 start
= ubuf
>> PAGE_SHIFT
;
7705 nr_pages
= end
- start
;
7707 ret
= io_account_mem(ctx
, nr_pages
, ACCT_PINNED
);
7712 if (!pages
|| nr_pages
> got_pages
) {
7715 pages
= kvmalloc_array(nr_pages
, sizeof(struct page
*),
7717 vmas
= kvmalloc_array(nr_pages
,
7718 sizeof(struct vm_area_struct
*),
7720 if (!pages
|| !vmas
) {
7722 io_unaccount_mem(ctx
, nr_pages
, ACCT_PINNED
);
7725 got_pages
= nr_pages
;
7728 imu
->bvec
= kvmalloc_array(nr_pages
, sizeof(struct bio_vec
),
7732 io_unaccount_mem(ctx
, nr_pages
, ACCT_PINNED
);
7737 mmap_read_lock(current
->mm
);
7738 pret
= pin_user_pages(ubuf
, nr_pages
,
7739 FOLL_WRITE
| FOLL_LONGTERM
,
7741 if (pret
== nr_pages
) {
7742 /* don't support file backed memory */
7743 for (j
= 0; j
< nr_pages
; j
++) {
7744 struct vm_area_struct
*vma
= vmas
[j
];
7747 !is_file_hugepages(vma
->vm_file
)) {
7753 ret
= pret
< 0 ? pret
: -EFAULT
;
7755 mmap_read_unlock(current
->mm
);
7758 * if we did partial map, or found file backed vmas,
7759 * release any pages we did get
7762 unpin_user_pages(pages
, pret
);
7763 io_unaccount_mem(ctx
, nr_pages
, ACCT_PINNED
);
7768 off
= ubuf
& ~PAGE_MASK
;
7770 for (j
= 0; j
< nr_pages
; j
++) {
7773 vec_len
= min_t(size_t, size
, PAGE_SIZE
- off
);
7774 imu
->bvec
[j
].bv_page
= pages
[j
];
7775 imu
->bvec
[j
].bv_len
= vec_len
;
7776 imu
->bvec
[j
].bv_offset
= off
;
7780 /* store original address for later verification */
7782 imu
->len
= iov
.iov_len
;
7783 imu
->nr_bvecs
= nr_pages
;
7785 ctx
->nr_user_bufs
++;
7793 io_sqe_buffer_unregister(ctx
);
7797 static int io_eventfd_register(struct io_ring_ctx
*ctx
, void __user
*arg
)
7799 __s32 __user
*fds
= arg
;
7805 if (copy_from_user(&fd
, fds
, sizeof(*fds
)))
7808 ctx
->cq_ev_fd
= eventfd_ctx_fdget(fd
);
7809 if (IS_ERR(ctx
->cq_ev_fd
)) {
7810 int ret
= PTR_ERR(ctx
->cq_ev_fd
);
7811 ctx
->cq_ev_fd
= NULL
;
7818 static int io_eventfd_unregister(struct io_ring_ctx
*ctx
)
7820 if (ctx
->cq_ev_fd
) {
7821 eventfd_ctx_put(ctx
->cq_ev_fd
);
7822 ctx
->cq_ev_fd
= NULL
;
7829 static int __io_destroy_buffers(int id
, void *p
, void *data
)
7831 struct io_ring_ctx
*ctx
= data
;
7832 struct io_buffer
*buf
= p
;
7834 __io_remove_buffers(ctx
, buf
, id
, -1U);
7838 static void io_destroy_buffers(struct io_ring_ctx
*ctx
)
7840 idr_for_each(&ctx
->io_buffer_idr
, __io_destroy_buffers
, ctx
);
7841 idr_destroy(&ctx
->io_buffer_idr
);
7844 static void io_ring_ctx_free(struct io_ring_ctx
*ctx
)
7846 io_finish_async(ctx
);
7847 io_sqe_buffer_unregister(ctx
);
7849 mmdrop(ctx
->sqo_mm
);
7853 io_sqe_files_unregister(ctx
);
7854 io_eventfd_unregister(ctx
);
7855 io_destroy_buffers(ctx
);
7856 idr_destroy(&ctx
->personality_idr
);
7858 #if defined(CONFIG_UNIX)
7859 if (ctx
->ring_sock
) {
7860 ctx
->ring_sock
->file
= NULL
; /* so that iput() is called */
7861 sock_release(ctx
->ring_sock
);
7865 io_mem_free(ctx
->rings
);
7866 io_mem_free(ctx
->sq_sqes
);
7868 percpu_ref_exit(&ctx
->refs
);
7869 free_uid(ctx
->user
);
7870 put_cred(ctx
->creds
);
7871 kfree(ctx
->cancel_hash
);
7872 kmem_cache_free(req_cachep
, ctx
->fallback_req
);
7876 static __poll_t
io_uring_poll(struct file
*file
, poll_table
*wait
)
7878 struct io_ring_ctx
*ctx
= file
->private_data
;
7881 poll_wait(file
, &ctx
->cq_wait
, wait
);
7883 * synchronizes with barrier from wq_has_sleeper call in
7887 if (READ_ONCE(ctx
->rings
->sq
.tail
) - ctx
->cached_sq_head
!=
7888 ctx
->rings
->sq_ring_entries
)
7889 mask
|= EPOLLOUT
| EPOLLWRNORM
;
7890 if (io_cqring_events(ctx
, false))
7891 mask
|= EPOLLIN
| EPOLLRDNORM
;
7896 static int io_uring_fasync(int fd
, struct file
*file
, int on
)
7898 struct io_ring_ctx
*ctx
= file
->private_data
;
7900 return fasync_helper(fd
, file
, on
, &ctx
->cq_fasync
);
7903 static int io_remove_personalities(int id
, void *p
, void *data
)
7905 struct io_ring_ctx
*ctx
= data
;
7906 const struct cred
*cred
;
7908 cred
= idr_remove(&ctx
->personality_idr
, id
);
7914 static void io_ring_exit_work(struct work_struct
*work
)
7916 struct io_ring_ctx
*ctx
= container_of(work
, struct io_ring_ctx
,
7920 * If we're doing polled IO and end up having requests being
7921 * submitted async (out-of-line), then completions can come in while
7922 * we're waiting for refs to drop. We need to reap these manually,
7923 * as nobody else will be looking for them.
7927 io_cqring_overflow_flush(ctx
, true);
7928 io_iopoll_try_reap_events(ctx
);
7929 } while (!wait_for_completion_timeout(&ctx
->ref_comp
, HZ
/20));
7930 io_ring_ctx_free(ctx
);
7933 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx
*ctx
)
7935 mutex_lock(&ctx
->uring_lock
);
7936 percpu_ref_kill(&ctx
->refs
);
7937 mutex_unlock(&ctx
->uring_lock
);
7939 io_kill_timeouts(ctx
);
7940 io_poll_remove_all(ctx
);
7943 io_wq_cancel_all(ctx
->io_wq
);
7945 /* if we failed setting up the ctx, we might not have any rings */
7947 io_cqring_overflow_flush(ctx
, true);
7948 io_iopoll_try_reap_events(ctx
);
7949 idr_for_each(&ctx
->personality_idr
, io_remove_personalities
, ctx
);
7952 * Do this upfront, so we won't have a grace period where the ring
7953 * is closed but resources aren't reaped yet. This can cause
7954 * spurious failure in setting up a new ring.
7956 io_unaccount_mem(ctx
, ring_pages(ctx
->sq_entries
, ctx
->cq_entries
),
7959 INIT_WORK(&ctx
->exit_work
, io_ring_exit_work
);
7961 * Use system_unbound_wq to avoid spawning tons of event kworkers
7962 * if we're exiting a ton of rings at the same time. It just adds
7963 * noise and overhead, there's no discernable change in runtime
7964 * over using system_wq.
7966 queue_work(system_unbound_wq
, &ctx
->exit_work
);
7969 static int io_uring_release(struct inode
*inode
, struct file
*file
)
7971 struct io_ring_ctx
*ctx
= file
->private_data
;
7973 file
->private_data
= NULL
;
7974 io_ring_ctx_wait_and_kill(ctx
);
7978 static bool io_wq_files_match(struct io_wq_work
*work
, void *data
)
7980 struct files_struct
*files
= data
;
7982 return work
->files
== files
;
7986 * Returns true if 'preq' is the link parent of 'req'
7988 static bool io_match_link(struct io_kiocb
*preq
, struct io_kiocb
*req
)
7990 struct io_kiocb
*link
;
7992 if (!(preq
->flags
& REQ_F_LINK_HEAD
))
7995 list_for_each_entry(link
, &preq
->link_list
, link_list
) {
8004 * We're looking to cancel 'req' because it's holding on to our files, but
8005 * 'req' could be a link to another request. See if it is, and cancel that
8006 * parent request if so.
8008 static bool io_poll_remove_link(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
)
8010 struct hlist_node
*tmp
;
8011 struct io_kiocb
*preq
;
8015 spin_lock_irq(&ctx
->completion_lock
);
8016 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
8017 struct hlist_head
*list
;
8019 list
= &ctx
->cancel_hash
[i
];
8020 hlist_for_each_entry_safe(preq
, tmp
, list
, hash_node
) {
8021 found
= io_match_link(preq
, req
);
8023 io_poll_remove_one(preq
);
8028 spin_unlock_irq(&ctx
->completion_lock
);
8032 static bool io_timeout_remove_link(struct io_ring_ctx
*ctx
,
8033 struct io_kiocb
*req
)
8035 struct io_kiocb
*preq
;
8038 spin_lock_irq(&ctx
->completion_lock
);
8039 list_for_each_entry(preq
, &ctx
->timeout_list
, timeout
.list
) {
8040 found
= io_match_link(preq
, req
);
8042 __io_timeout_cancel(preq
);
8046 spin_unlock_irq(&ctx
->completion_lock
);
8050 static bool io_cancel_link_cb(struct io_wq_work
*work
, void *data
)
8052 return io_match_link(container_of(work
, struct io_kiocb
, work
), data
);
8055 static void io_attempt_cancel(struct io_ring_ctx
*ctx
, struct io_kiocb
*req
)
8057 enum io_wq_cancel cret
;
8059 /* cancel this particular work, if it's running */
8060 cret
= io_wq_cancel_work(ctx
->io_wq
, &req
->work
);
8061 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8064 /* find links that hold this pending, cancel those */
8065 cret
= io_wq_cancel_cb(ctx
->io_wq
, io_cancel_link_cb
, req
, true);
8066 if (cret
!= IO_WQ_CANCEL_NOTFOUND
)
8069 /* if we have a poll link holding this pending, cancel that */
8070 if (io_poll_remove_link(ctx
, req
))
8073 /* final option, timeout link is holding this req pending */
8074 io_timeout_remove_link(ctx
, req
);
8077 static void io_uring_cancel_files(struct io_ring_ctx
*ctx
,
8078 struct files_struct
*files
)
8080 if (list_empty_careful(&ctx
->inflight_list
))
8083 /* cancel all at once, should be faster than doing it one by one*/
8084 io_wq_cancel_cb(ctx
->io_wq
, io_wq_files_match
, files
, true);
8086 while (!list_empty_careful(&ctx
->inflight_list
)) {
8087 struct io_kiocb
*cancel_req
= NULL
, *req
;
8090 spin_lock_irq(&ctx
->inflight_lock
);
8091 list_for_each_entry(req
, &ctx
->inflight_list
, inflight_entry
) {
8092 if (req
->work
.files
!= files
)
8094 /* req is being completed, ignore */
8095 if (!refcount_inc_not_zero(&req
->refs
))
8101 prepare_to_wait(&ctx
->inflight_wait
, &wait
,
8102 TASK_UNINTERRUPTIBLE
);
8103 spin_unlock_irq(&ctx
->inflight_lock
);
8105 /* We need to keep going until we don't find a matching req */
8108 /* cancel this request, or head link requests */
8109 io_attempt_cancel(ctx
, cancel_req
);
8110 io_put_req(cancel_req
);
8112 finish_wait(&ctx
->inflight_wait
, &wait
);
8116 static bool io_cancel_task_cb(struct io_wq_work
*work
, void *data
)
8118 struct io_kiocb
*req
= container_of(work
, struct io_kiocb
, work
);
8119 struct task_struct
*task
= data
;
8121 return req
->task
== task
;
8124 static int io_uring_flush(struct file
*file
, void *data
)
8126 struct io_ring_ctx
*ctx
= file
->private_data
;
8128 io_uring_cancel_files(ctx
, data
);
8131 * If the task is going away, cancel work it may have pending
8133 if (fatal_signal_pending(current
) || (current
->flags
& PF_EXITING
))
8134 io_wq_cancel_cb(ctx
->io_wq
, io_cancel_task_cb
, current
, true);
8139 static void *io_uring_validate_mmap_request(struct file
*file
,
8140 loff_t pgoff
, size_t sz
)
8142 struct io_ring_ctx
*ctx
= file
->private_data
;
8143 loff_t offset
= pgoff
<< PAGE_SHIFT
;
8148 case IORING_OFF_SQ_RING
:
8149 case IORING_OFF_CQ_RING
:
8152 case IORING_OFF_SQES
:
8156 return ERR_PTR(-EINVAL
);
8159 page
= virt_to_head_page(ptr
);
8160 if (sz
> page_size(page
))
8161 return ERR_PTR(-EINVAL
);
8168 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
8170 size_t sz
= vma
->vm_end
- vma
->vm_start
;
8174 ptr
= io_uring_validate_mmap_request(file
, vma
->vm_pgoff
, sz
);
8176 return PTR_ERR(ptr
);
8178 pfn
= virt_to_phys(ptr
) >> PAGE_SHIFT
;
8179 return remap_pfn_range(vma
, vma
->vm_start
, pfn
, sz
, vma
->vm_page_prot
);
8182 #else /* !CONFIG_MMU */
8184 static int io_uring_mmap(struct file
*file
, struct vm_area_struct
*vma
)
8186 return vma
->vm_flags
& (VM_SHARED
| VM_MAYSHARE
) ? 0 : -EINVAL
;
8189 static unsigned int io_uring_nommu_mmap_capabilities(struct file
*file
)
8191 return NOMMU_MAP_DIRECT
| NOMMU_MAP_READ
| NOMMU_MAP_WRITE
;
8194 static unsigned long io_uring_nommu_get_unmapped_area(struct file
*file
,
8195 unsigned long addr
, unsigned long len
,
8196 unsigned long pgoff
, unsigned long flags
)
8200 ptr
= io_uring_validate_mmap_request(file
, pgoff
, len
);
8202 return PTR_ERR(ptr
);
8204 return (unsigned long) ptr
;
8207 #endif /* !CONFIG_MMU */
8209 SYSCALL_DEFINE6(io_uring_enter
, unsigned int, fd
, u32
, to_submit
,
8210 u32
, min_complete
, u32
, flags
, const sigset_t __user
*, sig
,
8213 struct io_ring_ctx
*ctx
;
8220 if (flags
& ~(IORING_ENTER_GETEVENTS
| IORING_ENTER_SQ_WAKEUP
))
8228 if (f
.file
->f_op
!= &io_uring_fops
)
8232 ctx
= f
.file
->private_data
;
8233 if (!percpu_ref_tryget(&ctx
->refs
))
8237 * For SQ polling, the thread will do all submissions and completions.
8238 * Just return the requested submit count, and wake the thread if
8242 if (ctx
->flags
& IORING_SETUP_SQPOLL
) {
8243 if (!list_empty_careful(&ctx
->cq_overflow_list
))
8244 io_cqring_overflow_flush(ctx
, false);
8245 if (flags
& IORING_ENTER_SQ_WAKEUP
)
8246 wake_up(&ctx
->sqo_wait
);
8247 submitted
= to_submit
;
8248 } else if (to_submit
) {
8249 mutex_lock(&ctx
->uring_lock
);
8250 submitted
= io_submit_sqes(ctx
, to_submit
, f
.file
, fd
);
8251 mutex_unlock(&ctx
->uring_lock
);
8253 if (submitted
!= to_submit
)
8256 if (flags
& IORING_ENTER_GETEVENTS
) {
8257 min_complete
= min(min_complete
, ctx
->cq_entries
);
8260 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
8261 * space applications don't need to do io completion events
8262 * polling again, they can rely on io_sq_thread to do polling
8263 * work, which can reduce cpu usage and uring_lock contention.
8265 if (ctx
->flags
& IORING_SETUP_IOPOLL
&&
8266 !(ctx
->flags
& IORING_SETUP_SQPOLL
)) {
8267 ret
= io_iopoll_check(ctx
, min_complete
);
8269 ret
= io_cqring_wait(ctx
, min_complete
, sig
, sigsz
);
8274 percpu_ref_put(&ctx
->refs
);
8277 return submitted
? submitted
: ret
;
8280 #ifdef CONFIG_PROC_FS
8281 static int io_uring_show_cred(int id
, void *p
, void *data
)
8283 const struct cred
*cred
= p
;
8284 struct seq_file
*m
= data
;
8285 struct user_namespace
*uns
= seq_user_ns(m
);
8286 struct group_info
*gi
;
8291 seq_printf(m
, "%5d\n", id
);
8292 seq_put_decimal_ull(m
, "\tUid:\t", from_kuid_munged(uns
, cred
->uid
));
8293 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->euid
));
8294 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->suid
));
8295 seq_put_decimal_ull(m
, "\t\t", from_kuid_munged(uns
, cred
->fsuid
));
8296 seq_put_decimal_ull(m
, "\n\tGid:\t", from_kgid_munged(uns
, cred
->gid
));
8297 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->egid
));
8298 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->sgid
));
8299 seq_put_decimal_ull(m
, "\t\t", from_kgid_munged(uns
, cred
->fsgid
));
8300 seq_puts(m
, "\n\tGroups:\t");
8301 gi
= cred
->group_info
;
8302 for (g
= 0; g
< gi
->ngroups
; g
++) {
8303 seq_put_decimal_ull(m
, g
? " " : "",
8304 from_kgid_munged(uns
, gi
->gid
[g
]));
8306 seq_puts(m
, "\n\tCapEff:\t");
8307 cap
= cred
->cap_effective
;
8308 CAP_FOR_EACH_U32(__capi
)
8309 seq_put_hex_ll(m
, NULL
, cap
.cap
[CAP_LAST_U32
- __capi
], 8);
8314 static void __io_uring_show_fdinfo(struct io_ring_ctx
*ctx
, struct seq_file
*m
)
8318 mutex_lock(&ctx
->uring_lock
);
8319 seq_printf(m
, "UserFiles:\t%u\n", ctx
->nr_user_files
);
8320 for (i
= 0; i
< ctx
->nr_user_files
; i
++) {
8321 struct fixed_file_table
*table
;
8324 table
= &ctx
->file_data
->table
[i
>> IORING_FILE_TABLE_SHIFT
];
8325 f
= table
->files
[i
& IORING_FILE_TABLE_MASK
];
8327 seq_printf(m
, "%5u: %s\n", i
, file_dentry(f
)->d_iname
);
8329 seq_printf(m
, "%5u: <none>\n", i
);
8331 seq_printf(m
, "UserBufs:\t%u\n", ctx
->nr_user_bufs
);
8332 for (i
= 0; i
< ctx
->nr_user_bufs
; i
++) {
8333 struct io_mapped_ubuf
*buf
= &ctx
->user_bufs
[i
];
8335 seq_printf(m
, "%5u: 0x%llx/%u\n", i
, buf
->ubuf
,
8336 (unsigned int) buf
->len
);
8338 if (!idr_is_empty(&ctx
->personality_idr
)) {
8339 seq_printf(m
, "Personalities:\n");
8340 idr_for_each(&ctx
->personality_idr
, io_uring_show_cred
, m
);
8342 seq_printf(m
, "PollList:\n");
8343 spin_lock_irq(&ctx
->completion_lock
);
8344 for (i
= 0; i
< (1U << ctx
->cancel_hash_bits
); i
++) {
8345 struct hlist_head
*list
= &ctx
->cancel_hash
[i
];
8346 struct io_kiocb
*req
;
8348 hlist_for_each_entry(req
, list
, hash_node
)
8349 seq_printf(m
, " op=%d, task_works=%d\n", req
->opcode
,
8350 req
->task
->task_works
!= NULL
);
8352 spin_unlock_irq(&ctx
->completion_lock
);
8353 mutex_unlock(&ctx
->uring_lock
);
8356 static void io_uring_show_fdinfo(struct seq_file
*m
, struct file
*f
)
8358 struct io_ring_ctx
*ctx
= f
->private_data
;
8360 if (percpu_ref_tryget(&ctx
->refs
)) {
8361 __io_uring_show_fdinfo(ctx
, m
);
8362 percpu_ref_put(&ctx
->refs
);
8367 static const struct file_operations io_uring_fops
= {
8368 .release
= io_uring_release
,
8369 .flush
= io_uring_flush
,
8370 .mmap
= io_uring_mmap
,
8372 .get_unmapped_area
= io_uring_nommu_get_unmapped_area
,
8373 .mmap_capabilities
= io_uring_nommu_mmap_capabilities
,
8375 .poll
= io_uring_poll
,
8376 .fasync
= io_uring_fasync
,
8377 #ifdef CONFIG_PROC_FS
8378 .show_fdinfo
= io_uring_show_fdinfo
,
8382 static int io_allocate_scq_urings(struct io_ring_ctx
*ctx
,
8383 struct io_uring_params
*p
)
8385 struct io_rings
*rings
;
8386 size_t size
, sq_array_offset
;
8388 /* make sure these are sane, as we already accounted them */
8389 ctx
->sq_entries
= p
->sq_entries
;
8390 ctx
->cq_entries
= p
->cq_entries
;
8392 size
= rings_size(p
->sq_entries
, p
->cq_entries
, &sq_array_offset
);
8393 if (size
== SIZE_MAX
)
8396 rings
= io_mem_alloc(size
);
8401 ctx
->sq_array
= (u32
*)((char *)rings
+ sq_array_offset
);
8402 rings
->sq_ring_mask
= p
->sq_entries
- 1;
8403 rings
->cq_ring_mask
= p
->cq_entries
- 1;
8404 rings
->sq_ring_entries
= p
->sq_entries
;
8405 rings
->cq_ring_entries
= p
->cq_entries
;
8406 ctx
->sq_mask
= rings
->sq_ring_mask
;
8407 ctx
->cq_mask
= rings
->cq_ring_mask
;
8409 size
= array_size(sizeof(struct io_uring_sqe
), p
->sq_entries
);
8410 if (size
== SIZE_MAX
) {
8411 io_mem_free(ctx
->rings
);
8416 ctx
->sq_sqes
= io_mem_alloc(size
);
8417 if (!ctx
->sq_sqes
) {
8418 io_mem_free(ctx
->rings
);
8427 * Allocate an anonymous fd, this is what constitutes the application
8428 * visible backing of an io_uring instance. The application mmaps this
8429 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
8430 * we have to tie this fd to a socket for file garbage collection purposes.
8432 static int io_uring_get_fd(struct io_ring_ctx
*ctx
)
8437 #if defined(CONFIG_UNIX)
8438 ret
= sock_create_kern(&init_net
, PF_UNIX
, SOCK_RAW
, IPPROTO_IP
,
8444 ret
= get_unused_fd_flags(O_RDWR
| O_CLOEXEC
);
8448 file
= anon_inode_getfile("[io_uring]", &io_uring_fops
, ctx
,
8449 O_RDWR
| O_CLOEXEC
);
8452 ret
= PTR_ERR(file
);
8456 #if defined(CONFIG_UNIX)
8457 ctx
->ring_sock
->file
= file
;
8459 fd_install(ret
, file
);
8462 #if defined(CONFIG_UNIX)
8463 sock_release(ctx
->ring_sock
);
8464 ctx
->ring_sock
= NULL
;
8469 static int io_uring_create(unsigned entries
, struct io_uring_params
*p
,
8470 struct io_uring_params __user
*params
)
8472 struct user_struct
*user
= NULL
;
8473 struct io_ring_ctx
*ctx
;
8479 if (entries
> IORING_MAX_ENTRIES
) {
8480 if (!(p
->flags
& IORING_SETUP_CLAMP
))
8482 entries
= IORING_MAX_ENTRIES
;
8486 * Use twice as many entries for the CQ ring. It's possible for the
8487 * application to drive a higher depth than the size of the SQ ring,
8488 * since the sqes are only used at submission time. This allows for
8489 * some flexibility in overcommitting a bit. If the application has
8490 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
8491 * of CQ ring entries manually.
8493 p
->sq_entries
= roundup_pow_of_two(entries
);
8494 if (p
->flags
& IORING_SETUP_CQSIZE
) {
8496 * If IORING_SETUP_CQSIZE is set, we do the same roundup
8497 * to a power-of-two, if it isn't already. We do NOT impose
8498 * any cq vs sq ring sizing.
8500 if (p
->cq_entries
< p
->sq_entries
)
8502 if (p
->cq_entries
> IORING_MAX_CQ_ENTRIES
) {
8503 if (!(p
->flags
& IORING_SETUP_CLAMP
))
8505 p
->cq_entries
= IORING_MAX_CQ_ENTRIES
;
8507 p
->cq_entries
= roundup_pow_of_two(p
->cq_entries
);
8509 p
->cq_entries
= 2 * p
->sq_entries
;
8512 user
= get_uid(current_user());
8513 limit_mem
= !capable(CAP_IPC_LOCK
);
8516 ret
= __io_account_mem(user
,
8517 ring_pages(p
->sq_entries
, p
->cq_entries
));
8524 ctx
= io_ring_ctx_alloc(p
);
8527 __io_unaccount_mem(user
, ring_pages(p
->sq_entries
,
8532 ctx
->compat
= in_compat_syscall();
8534 ctx
->creds
= get_current_cred();
8537 * Account memory _before_ installing the file descriptor. Once
8538 * the descriptor is installed, it can get closed at any time. Also
8539 * do this before hitting the general error path, as ring freeing
8540 * will un-account as well.
8542 io_account_mem(ctx
, ring_pages(p
->sq_entries
, p
->cq_entries
),
8544 ctx
->limit_mem
= limit_mem
;
8546 ret
= io_allocate_scq_urings(ctx
, p
);
8550 ret
= io_sq_offload_start(ctx
, p
);
8554 memset(&p
->sq_off
, 0, sizeof(p
->sq_off
));
8555 p
->sq_off
.head
= offsetof(struct io_rings
, sq
.head
);
8556 p
->sq_off
.tail
= offsetof(struct io_rings
, sq
.tail
);
8557 p
->sq_off
.ring_mask
= offsetof(struct io_rings
, sq_ring_mask
);
8558 p
->sq_off
.ring_entries
= offsetof(struct io_rings
, sq_ring_entries
);
8559 p
->sq_off
.flags
= offsetof(struct io_rings
, sq_flags
);
8560 p
->sq_off
.dropped
= offsetof(struct io_rings
, sq_dropped
);
8561 p
->sq_off
.array
= (char *)ctx
->sq_array
- (char *)ctx
->rings
;
8563 memset(&p
->cq_off
, 0, sizeof(p
->cq_off
));
8564 p
->cq_off
.head
= offsetof(struct io_rings
, cq
.head
);
8565 p
->cq_off
.tail
= offsetof(struct io_rings
, cq
.tail
);
8566 p
->cq_off
.ring_mask
= offsetof(struct io_rings
, cq_ring_mask
);
8567 p
->cq_off
.ring_entries
= offsetof(struct io_rings
, cq_ring_entries
);
8568 p
->cq_off
.overflow
= offsetof(struct io_rings
, cq_overflow
);
8569 p
->cq_off
.cqes
= offsetof(struct io_rings
, cqes
);
8570 p
->cq_off
.flags
= offsetof(struct io_rings
, cq_flags
);
8572 p
->features
= IORING_FEAT_SINGLE_MMAP
| IORING_FEAT_NODROP
|
8573 IORING_FEAT_SUBMIT_STABLE
| IORING_FEAT_RW_CUR_POS
|
8574 IORING_FEAT_CUR_PERSONALITY
| IORING_FEAT_FAST_POLL
|
8575 IORING_FEAT_POLL_32BITS
;
8577 if (copy_to_user(params
, p
, sizeof(*p
))) {
8583 * Install ring fd as the very last thing, so we don't risk someone
8584 * having closed it before we finish setup
8586 ret
= io_uring_get_fd(ctx
);
8590 trace_io_uring_create(ret
, ctx
, p
->sq_entries
, p
->cq_entries
, p
->flags
);
8593 io_ring_ctx_wait_and_kill(ctx
);
8598 * Sets up an aio uring context, and returns the fd. Applications asks for a
8599 * ring size, we return the actual sq/cq ring sizes (among other things) in the
8600 * params structure passed in.
8602 static long io_uring_setup(u32 entries
, struct io_uring_params __user
*params
)
8604 struct io_uring_params p
;
8607 if (copy_from_user(&p
, params
, sizeof(p
)))
8609 for (i
= 0; i
< ARRAY_SIZE(p
.resv
); i
++) {
8614 if (p
.flags
& ~(IORING_SETUP_IOPOLL
| IORING_SETUP_SQPOLL
|
8615 IORING_SETUP_SQ_AFF
| IORING_SETUP_CQSIZE
|
8616 IORING_SETUP_CLAMP
| IORING_SETUP_ATTACH_WQ
))
8619 return io_uring_create(entries
, &p
, params
);
8622 SYSCALL_DEFINE2(io_uring_setup
, u32
, entries
,
8623 struct io_uring_params __user
*, params
)
8625 return io_uring_setup(entries
, params
);
8628 static int io_probe(struct io_ring_ctx
*ctx
, void __user
*arg
, unsigned nr_args
)
8630 struct io_uring_probe
*p
;
8634 size
= struct_size(p
, ops
, nr_args
);
8635 if (size
== SIZE_MAX
)
8637 p
= kzalloc(size
, GFP_KERNEL
);
8642 if (copy_from_user(p
, arg
, size
))
8645 if (memchr_inv(p
, 0, size
))
8648 p
->last_op
= IORING_OP_LAST
- 1;
8649 if (nr_args
> IORING_OP_LAST
)
8650 nr_args
= IORING_OP_LAST
;
8652 for (i
= 0; i
< nr_args
; i
++) {
8654 if (!io_op_defs
[i
].not_supported
)
8655 p
->ops
[i
].flags
= IO_URING_OP_SUPPORTED
;
8660 if (copy_to_user(arg
, p
, size
))
8667 static int io_register_personality(struct io_ring_ctx
*ctx
)
8669 const struct cred
*creds
= get_current_cred();
8672 id
= idr_alloc_cyclic(&ctx
->personality_idr
, (void *) creds
, 1,
8673 USHRT_MAX
, GFP_KERNEL
);
8679 static int io_unregister_personality(struct io_ring_ctx
*ctx
, unsigned id
)
8681 const struct cred
*old_creds
;
8683 old_creds
= idr_remove(&ctx
->personality_idr
, id
);
8685 put_cred(old_creds
);
8692 static bool io_register_op_must_quiesce(int op
)
8695 case IORING_UNREGISTER_FILES
:
8696 case IORING_REGISTER_FILES_UPDATE
:
8697 case IORING_REGISTER_PROBE
:
8698 case IORING_REGISTER_PERSONALITY
:
8699 case IORING_UNREGISTER_PERSONALITY
:
8706 static int __io_uring_register(struct io_ring_ctx
*ctx
, unsigned opcode
,
8707 void __user
*arg
, unsigned nr_args
)
8708 __releases(ctx
->uring_lock
)
8709 __acquires(ctx
->uring_lock
)
8714 * We're inside the ring mutex, if the ref is already dying, then
8715 * someone else killed the ctx or is already going through
8716 * io_uring_register().
8718 if (percpu_ref_is_dying(&ctx
->refs
))
8721 if (io_register_op_must_quiesce(opcode
)) {
8722 percpu_ref_kill(&ctx
->refs
);
8725 * Drop uring mutex before waiting for references to exit. If
8726 * another thread is currently inside io_uring_enter() it might
8727 * need to grab the uring_lock to make progress. If we hold it
8728 * here across the drain wait, then we can deadlock. It's safe
8729 * to drop the mutex here, since no new references will come in
8730 * after we've killed the percpu ref.
8732 mutex_unlock(&ctx
->uring_lock
);
8733 ret
= wait_for_completion_interruptible(&ctx
->ref_comp
);
8734 mutex_lock(&ctx
->uring_lock
);
8736 percpu_ref_resurrect(&ctx
->refs
);
8743 case IORING_REGISTER_BUFFERS
:
8744 ret
= io_sqe_buffer_register(ctx
, arg
, nr_args
);
8746 case IORING_UNREGISTER_BUFFERS
:
8750 ret
= io_sqe_buffer_unregister(ctx
);
8752 case IORING_REGISTER_FILES
:
8753 ret
= io_sqe_files_register(ctx
, arg
, nr_args
);
8755 case IORING_UNREGISTER_FILES
:
8759 ret
= io_sqe_files_unregister(ctx
);
8761 case IORING_REGISTER_FILES_UPDATE
:
8762 ret
= io_sqe_files_update(ctx
, arg
, nr_args
);
8764 case IORING_REGISTER_EVENTFD
:
8765 case IORING_REGISTER_EVENTFD_ASYNC
:
8769 ret
= io_eventfd_register(ctx
, arg
);
8772 if (opcode
== IORING_REGISTER_EVENTFD_ASYNC
)
8773 ctx
->eventfd_async
= 1;
8775 ctx
->eventfd_async
= 0;
8777 case IORING_UNREGISTER_EVENTFD
:
8781 ret
= io_eventfd_unregister(ctx
);
8783 case IORING_REGISTER_PROBE
:
8785 if (!arg
|| nr_args
> 256)
8787 ret
= io_probe(ctx
, arg
, nr_args
);
8789 case IORING_REGISTER_PERSONALITY
:
8793 ret
= io_register_personality(ctx
);
8795 case IORING_UNREGISTER_PERSONALITY
:
8799 ret
= io_unregister_personality(ctx
, nr_args
);
8806 if (io_register_op_must_quiesce(opcode
)) {
8807 /* bring the ctx back to life */
8808 percpu_ref_reinit(&ctx
->refs
);
8810 reinit_completion(&ctx
->ref_comp
);
8815 SYSCALL_DEFINE4(io_uring_register
, unsigned int, fd
, unsigned int, opcode
,
8816 void __user
*, arg
, unsigned int, nr_args
)
8818 struct io_ring_ctx
*ctx
;
8827 if (f
.file
->f_op
!= &io_uring_fops
)
8830 ctx
= f
.file
->private_data
;
8832 mutex_lock(&ctx
->uring_lock
);
8833 ret
= __io_uring_register(ctx
, opcode
, arg
, nr_args
);
8834 mutex_unlock(&ctx
->uring_lock
);
8835 trace_io_uring_register(ctx
, opcode
, ctx
->nr_user_files
, ctx
->nr_user_bufs
,
8836 ctx
->cq_ev_fd
!= NULL
, ret
);
8842 static int __init
io_uring_init(void)
8844 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
8845 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
8846 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
8849 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
8850 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
8851 BUILD_BUG_ON(sizeof(struct io_uring_sqe
) != 64);
8852 BUILD_BUG_SQE_ELEM(0, __u8
, opcode
);
8853 BUILD_BUG_SQE_ELEM(1, __u8
, flags
);
8854 BUILD_BUG_SQE_ELEM(2, __u16
, ioprio
);
8855 BUILD_BUG_SQE_ELEM(4, __s32
, fd
);
8856 BUILD_BUG_SQE_ELEM(8, __u64
, off
);
8857 BUILD_BUG_SQE_ELEM(8, __u64
, addr2
);
8858 BUILD_BUG_SQE_ELEM(16, __u64
, addr
);
8859 BUILD_BUG_SQE_ELEM(16, __u64
, splice_off_in
);
8860 BUILD_BUG_SQE_ELEM(24, __u32
, len
);
8861 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t
, rw_flags
);
8862 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags
);
8863 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32
, rw_flags
);
8864 BUILD_BUG_SQE_ELEM(28, __u32
, fsync_flags
);
8865 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16
, poll_events
);
8866 BUILD_BUG_SQE_ELEM(28, __u32
, poll32_events
);
8867 BUILD_BUG_SQE_ELEM(28, __u32
, sync_range_flags
);
8868 BUILD_BUG_SQE_ELEM(28, __u32
, msg_flags
);
8869 BUILD_BUG_SQE_ELEM(28, __u32
, timeout_flags
);
8870 BUILD_BUG_SQE_ELEM(28, __u32
, accept_flags
);
8871 BUILD_BUG_SQE_ELEM(28, __u32
, cancel_flags
);
8872 BUILD_BUG_SQE_ELEM(28, __u32
, open_flags
);
8873 BUILD_BUG_SQE_ELEM(28, __u32
, statx_flags
);
8874 BUILD_BUG_SQE_ELEM(28, __u32
, fadvise_advice
);
8875 BUILD_BUG_SQE_ELEM(28, __u32
, splice_flags
);
8876 BUILD_BUG_SQE_ELEM(32, __u64
, user_data
);
8877 BUILD_BUG_SQE_ELEM(40, __u16
, buf_index
);
8878 BUILD_BUG_SQE_ELEM(42, __u16
, personality
);
8879 BUILD_BUG_SQE_ELEM(44, __s32
, splice_fd_in
);
8881 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs
) != IORING_OP_LAST
);
8882 BUILD_BUG_ON(__REQ_F_LAST_BIT
>= 8 * sizeof(int));
8883 req_cachep
= KMEM_CACHE(io_kiocb
, SLAB_HWCACHE_ALIGN
| SLAB_PANIC
);
8886 __initcall(io_uring_init
);