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/blkdev.h>
61 #include <linux/bvec.h>
62 #include <linux/net.h>
64 #include <net/af_unix.h>
66 #include <linux/anon_inodes.h>
67 #include <linux/sched/mm.h>
68 #include <linux/uaccess.h>
69 #include <linux/nospec.h>
70 #include <linux/sizes.h>
71 #include <linux/hugetlb.h>
72 #include <linux/highmem.h>
73 #include <linux/namei.h>
74 #include <linux/fsnotify.h>
75 #include <linux/fadvise.h>
76 #include <linux/eventpoll.h>
77 #include <linux/splice.h>
78 #include <linux/task_work.h>
79 #include <linux/pagemap.h>
80 #include <linux/io_uring.h>
81 #include <linux/freezer.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)
101 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
102 IORING_REGISTER_LAST + IORING_OP_LAST)
104 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
105 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
109 u32 head ____cacheline_aligned_in_smp;
110 u32 tail ____cacheline_aligned_in_smp;
114 * This data is shared with the application through the mmap at offsets
115 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
117 * The offsets to the member fields are published through struct
118 * io_sqring_offsets when calling io_uring_setup.
122 * Head and tail offsets into the ring; the offsets need to be
123 * masked to get valid indices.
125 * The kernel controls head of the sq ring and the tail of the cq ring,
126 * and the application controls tail of the sq ring and the head of the
129 struct io_uring sq, cq;
131 * Bitmasks to apply to head and tail offsets (constant, equals
134 u32 sq_ring_mask, cq_ring_mask;
135 /* Ring sizes (constant, power of 2) */
136 u32 sq_ring_entries, cq_ring_entries;
138 * Number of invalid entries dropped by the kernel due to
139 * invalid index stored in array
141 * Written by the kernel, shouldn't be modified by the
142 * application (i.e. get number of "new events" by comparing to
145 * After a new SQ head value was read by the application this
146 * counter includes all submissions that were dropped reaching
147 * the new SQ head (and possibly more).
153 * Written by the kernel, shouldn't be modified by the
156 * The application needs a full memory barrier before checking
157 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
163 * Written by the application, shouldn't be modified by the
168 * Number of completion events lost because the queue was full;
169 * this should be avoided by the application by making sure
170 * there are not more requests pending than there is space in
171 * the completion queue.
173 * Written by the kernel, shouldn't be modified by the
174 * application (i.e. get number of "new events" by comparing to
177 * As completion events come in out of order this counter is not
178 * ordered with any other data.
182 * Ring buffer of completion events.
184 * The kernel writes completion events fresh every time they are
185 * produced, so the application is allowed to modify pending
188 struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp;
191 enum io_uring_cmd_flags {
192 IO_URING_F_NONBLOCK = 1,
193 IO_URING_F_COMPLETE_DEFER = 2,
196 struct io_mapped_ubuf {
199 struct bio_vec *bvec;
200 unsigned int nr_bvecs;
201 unsigned long acct_pages;
207 struct list_head list;
214 struct fixed_rsrc_table {
218 struct fixed_rsrc_ref_node {
219 struct percpu_ref refs;
220 struct list_head node;
221 struct list_head rsrc_list;
222 struct fixed_rsrc_data *rsrc_data;
223 void (*rsrc_put)(struct io_ring_ctx *ctx,
224 struct io_rsrc_put *prsrc);
225 struct llist_node llist;
229 struct fixed_rsrc_data {
230 struct fixed_rsrc_table *table;
231 struct io_ring_ctx *ctx;
233 struct fixed_rsrc_ref_node *node;
234 struct percpu_ref refs;
235 struct completion done;
240 struct list_head list;
246 struct io_restriction {
247 DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
248 DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
249 u8 sqe_flags_allowed;
250 u8 sqe_flags_required;
255 IO_SQ_THREAD_SHOULD_STOP = 0,
256 IO_SQ_THREAD_SHOULD_PARK,
261 struct rw_semaphore rw_lock;
263 /* ctx's that are using this sqd */
264 struct list_head ctx_list;
265 struct list_head ctx_new_list;
267 struct task_struct *thread;
268 struct wait_queue_head wait;
270 unsigned sq_thread_idle;
275 struct completion startup;
276 struct completion exited;
279 #define IO_IOPOLL_BATCH 8
280 #define IO_COMPL_BATCH 32
281 #define IO_REQ_CACHE_SIZE 32
282 #define IO_REQ_ALLOC_BATCH 8
284 struct io_comp_state {
285 struct io_kiocb *reqs[IO_COMPL_BATCH];
287 unsigned int locked_free_nr;
288 /* inline/task_work completion list, under ->uring_lock */
289 struct list_head free_list;
290 /* IRQ completion list, under ->completion_lock */
291 struct list_head locked_free_list;
294 struct io_submit_link {
295 struct io_kiocb *head;
296 struct io_kiocb *last;
299 struct io_submit_state {
300 struct blk_plug plug;
301 struct io_submit_link link;
304 * io_kiocb alloc cache
306 void *reqs[IO_REQ_CACHE_SIZE];
307 unsigned int free_reqs;
312 * Batch completion logic
314 struct io_comp_state comp;
317 * File reference cache
321 unsigned int file_refs;
322 unsigned int ios_left;
327 struct percpu_ref refs;
328 } ____cacheline_aligned_in_smp;
332 unsigned int compat: 1;
333 unsigned int cq_overflow_flushed: 1;
334 unsigned int drain_next: 1;
335 unsigned int eventfd_async: 1;
336 unsigned int restricted: 1;
339 * Ring buffer of indices into array of io_uring_sqe, which is
340 * mmapped by the application using the IORING_OFF_SQES offset.
342 * This indirection could e.g. be used to assign fixed
343 * io_uring_sqe entries to operations and only submit them to
344 * the queue when needed.
346 * The kernel modifies neither the indices array nor the entries
350 unsigned cached_sq_head;
353 unsigned sq_thread_idle;
354 unsigned cached_sq_dropped;
355 unsigned cached_cq_overflow;
356 unsigned long sq_check_overflow;
358 /* hashed buffered write serialization */
359 struct io_wq_hash *hash_map;
361 struct list_head defer_list;
362 struct list_head timeout_list;
363 struct list_head cq_overflow_list;
365 struct io_uring_sqe *sq_sqes;
366 } ____cacheline_aligned_in_smp;
369 struct mutex uring_lock;
370 wait_queue_head_t wait;
371 } ____cacheline_aligned_in_smp;
373 struct io_submit_state submit_state;
375 struct io_rings *rings;
377 /* Only used for accounting purposes */
378 struct mm_struct *mm_account;
380 const struct cred *sq_creds; /* cred used for __io_sq_thread() */
381 struct io_sq_data *sq_data; /* if using sq thread polling */
383 struct wait_queue_head sqo_sq_wait;
384 struct list_head sqd_list;
387 * If used, fixed file set. Writers must ensure that ->refs is dead,
388 * readers must ensure that ->refs is alive as long as the file* is
389 * used. Only updated through io_uring_register(2).
391 struct fixed_rsrc_data *file_data;
392 unsigned nr_user_files;
394 /* if used, fixed mapped user buffers */
395 unsigned nr_user_bufs;
396 struct io_mapped_ubuf *user_bufs;
398 struct user_struct *user;
400 struct completion ref_comp;
401 struct completion sq_thread_comp;
403 #if defined(CONFIG_UNIX)
404 struct socket *ring_sock;
407 struct idr io_buffer_idr;
409 struct xarray personalities;
413 unsigned cached_cq_tail;
416 atomic_t cq_timeouts;
417 unsigned cq_last_tm_flush;
418 unsigned long cq_check_overflow;
419 struct wait_queue_head cq_wait;
420 struct fasync_struct *cq_fasync;
421 struct eventfd_ctx *cq_ev_fd;
422 } ____cacheline_aligned_in_smp;
425 spinlock_t completion_lock;
428 * ->iopoll_list is protected by the ctx->uring_lock for
429 * io_uring instances that don't use IORING_SETUP_SQPOLL.
430 * For SQPOLL, only the single threaded io_sq_thread() will
431 * manipulate the list, hence no extra locking is needed there.
433 struct list_head iopoll_list;
434 struct hlist_head *cancel_hash;
435 unsigned cancel_hash_bits;
436 bool poll_multi_file;
438 spinlock_t inflight_lock;
439 struct list_head inflight_list;
440 } ____cacheline_aligned_in_smp;
442 struct delayed_work rsrc_put_work;
443 struct llist_head rsrc_put_llist;
444 struct list_head rsrc_ref_list;
445 spinlock_t rsrc_ref_lock;
447 struct io_restriction restrictions;
450 struct callback_head *exit_task_work;
452 struct wait_queue_head hash_wait;
454 /* Keep this last, we don't need it for the fast path */
455 struct work_struct exit_work;
456 struct list_head tctx_list;
460 * First field must be the file pointer in all the
461 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
463 struct io_poll_iocb {
465 struct wait_queue_head *head;
469 struct wait_queue_entry wait;
472 struct io_poll_remove {
482 struct io_timeout_data {
483 struct io_kiocb *req;
484 struct hrtimer timer;
485 struct timespec64 ts;
486 enum hrtimer_mode mode;
491 struct sockaddr __user *addr;
492 int __user *addr_len;
494 unsigned long nofile;
514 struct list_head list;
515 /* head of the link, used by linked timeouts only */
516 struct io_kiocb *head;
519 struct io_timeout_rem {
524 struct timespec64 ts;
529 /* NOTE: kiocb has the file as the first member, so don't do it here */
537 struct sockaddr __user *addr;
544 struct user_msghdr __user *umsg;
550 struct io_buffer *kbuf;
556 struct filename *filename;
558 unsigned long nofile;
561 struct io_rsrc_update {
587 struct epoll_event event;
591 struct file *file_out;
592 struct file *file_in;
599 struct io_provide_buf {
613 const char __user *filename;
614 struct statx __user *buffer;
626 struct filename *oldpath;
627 struct filename *newpath;
635 struct filename *filename;
638 struct io_completion {
640 struct list_head list;
644 struct io_async_connect {
645 struct sockaddr_storage address;
648 struct io_async_msghdr {
649 struct iovec fast_iov[UIO_FASTIOV];
650 /* points to an allocated iov, if NULL we use fast_iov instead */
651 struct iovec *free_iov;
652 struct sockaddr __user *uaddr;
654 struct sockaddr_storage addr;
658 struct iovec fast_iov[UIO_FASTIOV];
659 const struct iovec *free_iovec;
660 struct iov_iter iter;
662 struct wait_page_queue wpq;
666 REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
667 REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
668 REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
669 REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
670 REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
671 REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
677 REQ_F_LINK_TIMEOUT_BIT,
679 REQ_F_NEED_CLEANUP_BIT,
681 REQ_F_BUFFER_SELECTED_BIT,
682 REQ_F_NO_FILE_TABLE_BIT,
683 REQ_F_LTIMEOUT_ACTIVE_BIT,
684 REQ_F_COMPLETE_INLINE_BIT,
686 /* not a real bit, just to check we're not overflowing the space */
692 REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
693 /* drain existing IO first */
694 REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
696 REQ_F_LINK = BIT(REQ_F_LINK_BIT),
697 /* doesn't sever on completion < 0 */
698 REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
700 REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
701 /* IOSQE_BUFFER_SELECT */
702 REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
704 /* fail rest of links */
705 REQ_F_FAIL_LINK = BIT(REQ_F_FAIL_LINK_BIT),
706 /* on inflight list, should be cancelled and waited on exit reliably */
707 REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
708 /* read/write uses file position */
709 REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
710 /* must not punt to workers */
711 REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
712 /* has or had linked timeout */
713 REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
715 REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
717 REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
718 /* already went through poll handler */
719 REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
720 /* buffer already selected */
721 REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
722 /* doesn't need file table for this request */
723 REQ_F_NO_FILE_TABLE = BIT(REQ_F_NO_FILE_TABLE_BIT),
724 /* linked timeout is active, i.e. prepared by link's head */
725 REQ_F_LTIMEOUT_ACTIVE = BIT(REQ_F_LTIMEOUT_ACTIVE_BIT),
726 /* completion is deferred through io_comp_state */
727 REQ_F_COMPLETE_INLINE = BIT(REQ_F_COMPLETE_INLINE_BIT),
731 struct io_poll_iocb poll;
732 struct io_poll_iocb *double_poll;
735 struct io_task_work {
736 struct io_wq_work_node node;
737 task_work_func_t func;
741 * NOTE! Each of the iocb union members has the file pointer
742 * as the first entry in their struct definition. So you can
743 * access the file pointer through any of the sub-structs,
744 * or directly as just 'ki_filp' in this struct.
750 struct io_poll_iocb poll;
751 struct io_poll_remove poll_remove;
752 struct io_accept accept;
754 struct io_cancel cancel;
755 struct io_timeout timeout;
756 struct io_timeout_rem timeout_rem;
757 struct io_connect connect;
758 struct io_sr_msg sr_msg;
760 struct io_close close;
761 struct io_rsrc_update rsrc_update;
762 struct io_fadvise fadvise;
763 struct io_madvise madvise;
764 struct io_epoll epoll;
765 struct io_splice splice;
766 struct io_provide_buf pbuf;
767 struct io_statx statx;
768 struct io_shutdown shutdown;
769 struct io_rename rename;
770 struct io_unlink unlink;
771 /* use only after cleaning per-op data, see io_clean_op() */
772 struct io_completion compl;
775 /* opcode allocated if it needs to store data for async defer */
778 /* polled IO has completed */
784 struct io_ring_ctx *ctx;
787 struct task_struct *task;
790 struct io_kiocb *link;
791 struct percpu_ref *fixed_rsrc_refs;
794 * 1. used with ctx->iopoll_list with reads/writes
795 * 2. to track reqs with ->files (see io_op_def::file_table)
797 struct list_head inflight_entry;
799 struct io_task_work io_task_work;
800 struct callback_head task_work;
802 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
803 struct hlist_node hash_node;
804 struct async_poll *apoll;
805 struct io_wq_work work;
808 struct io_tctx_node {
809 struct list_head ctx_node;
810 struct task_struct *task;
811 struct io_ring_ctx *ctx;
814 struct io_defer_entry {
815 struct list_head list;
816 struct io_kiocb *req;
821 /* needs req->file assigned */
822 unsigned needs_file : 1;
823 /* hash wq insertion if file is a regular file */
824 unsigned hash_reg_file : 1;
825 /* unbound wq insertion if file is a non-regular file */
826 unsigned unbound_nonreg_file : 1;
827 /* opcode is not supported by this kernel */
828 unsigned not_supported : 1;
829 /* set if opcode supports polled "wait" */
831 unsigned pollout : 1;
832 /* op supports buffer selection */
833 unsigned buffer_select : 1;
834 /* must always have async data allocated */
835 unsigned needs_async_data : 1;
836 /* should block plug */
838 /* size of async data needed, if any */
839 unsigned short async_size;
842 static const struct io_op_def io_op_defs[] = {
843 [IORING_OP_NOP] = {},
844 [IORING_OP_READV] = {
846 .unbound_nonreg_file = 1,
849 .needs_async_data = 1,
851 .async_size = sizeof(struct io_async_rw),
853 [IORING_OP_WRITEV] = {
856 .unbound_nonreg_file = 1,
858 .needs_async_data = 1,
860 .async_size = sizeof(struct io_async_rw),
862 [IORING_OP_FSYNC] = {
865 [IORING_OP_READ_FIXED] = {
867 .unbound_nonreg_file = 1,
870 .async_size = sizeof(struct io_async_rw),
872 [IORING_OP_WRITE_FIXED] = {
875 .unbound_nonreg_file = 1,
878 .async_size = sizeof(struct io_async_rw),
880 [IORING_OP_POLL_ADD] = {
882 .unbound_nonreg_file = 1,
884 [IORING_OP_POLL_REMOVE] = {},
885 [IORING_OP_SYNC_FILE_RANGE] = {
888 [IORING_OP_SENDMSG] = {
890 .unbound_nonreg_file = 1,
892 .needs_async_data = 1,
893 .async_size = sizeof(struct io_async_msghdr),
895 [IORING_OP_RECVMSG] = {
897 .unbound_nonreg_file = 1,
900 .needs_async_data = 1,
901 .async_size = sizeof(struct io_async_msghdr),
903 [IORING_OP_TIMEOUT] = {
904 .needs_async_data = 1,
905 .async_size = sizeof(struct io_timeout_data),
907 [IORING_OP_TIMEOUT_REMOVE] = {
908 /* used by timeout updates' prep() */
910 [IORING_OP_ACCEPT] = {
912 .unbound_nonreg_file = 1,
915 [IORING_OP_ASYNC_CANCEL] = {},
916 [IORING_OP_LINK_TIMEOUT] = {
917 .needs_async_data = 1,
918 .async_size = sizeof(struct io_timeout_data),
920 [IORING_OP_CONNECT] = {
922 .unbound_nonreg_file = 1,
924 .needs_async_data = 1,
925 .async_size = sizeof(struct io_async_connect),
927 [IORING_OP_FALLOCATE] = {
930 [IORING_OP_OPENAT] = {},
931 [IORING_OP_CLOSE] = {},
932 [IORING_OP_FILES_UPDATE] = {},
933 [IORING_OP_STATX] = {},
936 .unbound_nonreg_file = 1,
940 .async_size = sizeof(struct io_async_rw),
942 [IORING_OP_WRITE] = {
944 .unbound_nonreg_file = 1,
947 .async_size = sizeof(struct io_async_rw),
949 [IORING_OP_FADVISE] = {
952 [IORING_OP_MADVISE] = {},
955 .unbound_nonreg_file = 1,
960 .unbound_nonreg_file = 1,
964 [IORING_OP_OPENAT2] = {
966 [IORING_OP_EPOLL_CTL] = {
967 .unbound_nonreg_file = 1,
969 [IORING_OP_SPLICE] = {
972 .unbound_nonreg_file = 1,
974 [IORING_OP_PROVIDE_BUFFERS] = {},
975 [IORING_OP_REMOVE_BUFFERS] = {},
979 .unbound_nonreg_file = 1,
981 [IORING_OP_SHUTDOWN] = {
984 [IORING_OP_RENAMEAT] = {},
985 [IORING_OP_UNLINKAT] = {},
988 static void io_uring_del_task_file(unsigned long index);
989 static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
990 struct task_struct *task,
991 struct files_struct *files);
992 static void io_uring_cancel_sqpoll(struct io_ring_ctx *ctx);
993 static void destroy_fixed_rsrc_ref_node(struct fixed_rsrc_ref_node *ref_node);
994 static struct fixed_rsrc_ref_node *alloc_fixed_rsrc_ref_node(
995 struct io_ring_ctx *ctx);
996 static void io_ring_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
998 static bool io_rw_reissue(struct io_kiocb *req);
999 static void io_cqring_fill_event(struct io_kiocb *req, long res);
1000 static void io_put_req(struct io_kiocb *req);
1001 static void io_put_req_deferred(struct io_kiocb *req, int nr);
1002 static void io_double_put_req(struct io_kiocb *req);
1003 static void io_dismantle_req(struct io_kiocb *req);
1004 static void io_put_task(struct task_struct *task, int nr);
1005 static void io_queue_next(struct io_kiocb *req);
1006 static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req);
1007 static void __io_queue_linked_timeout(struct io_kiocb *req);
1008 static void io_queue_linked_timeout(struct io_kiocb *req);
1009 static int __io_sqe_files_update(struct io_ring_ctx *ctx,
1010 struct io_uring_rsrc_update *ip,
1012 static void __io_clean_op(struct io_kiocb *req);
1013 static struct file *io_file_get(struct io_submit_state *state,
1014 struct io_kiocb *req, int fd, bool fixed);
1015 static void __io_queue_sqe(struct io_kiocb *req);
1016 static void io_rsrc_put_work(struct work_struct *work);
1018 static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
1019 struct iov_iter *iter, bool needs_lock);
1020 static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
1021 const struct iovec *fast_iov,
1022 struct iov_iter *iter, bool force);
1023 static void io_req_task_queue(struct io_kiocb *req);
1024 static void io_submit_flush_completions(struct io_comp_state *cs,
1025 struct io_ring_ctx *ctx);
1027 static struct kmem_cache *req_cachep;
1029 static const struct file_operations io_uring_fops;
1031 struct sock *io_uring_get_socket(struct file *file)
1033 #if defined(CONFIG_UNIX)
1034 if (file->f_op == &io_uring_fops) {
1035 struct io_ring_ctx *ctx = file->private_data;
1037 return ctx->ring_sock->sk;
1042 EXPORT_SYMBOL(io_uring_get_socket);
1044 #define io_for_each_link(pos, head) \
1045 for (pos = (head); pos; pos = pos->link)
1047 static inline void io_clean_op(struct io_kiocb *req)
1049 if (req->flags & (REQ_F_NEED_CLEANUP | REQ_F_BUFFER_SELECTED))
1053 static inline void io_set_resource_node(struct io_kiocb *req)
1055 struct io_ring_ctx *ctx = req->ctx;
1057 if (!req->fixed_rsrc_refs) {
1058 req->fixed_rsrc_refs = &ctx->file_data->node->refs;
1059 percpu_ref_get(req->fixed_rsrc_refs);
1063 static bool io_match_task(struct io_kiocb *head,
1064 struct task_struct *task,
1065 struct files_struct *files)
1067 struct io_kiocb *req;
1069 if (task && head->task != task) {
1070 /* in terms of cancelation, always match if req task is dead */
1071 if (head->task->flags & PF_EXITING)
1078 io_for_each_link(req, head) {
1079 if (req->flags & REQ_F_INFLIGHT)
1081 if (req->task->files == files)
1087 static inline void req_set_fail_links(struct io_kiocb *req)
1089 if ((req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) == REQ_F_LINK)
1090 req->flags |= REQ_F_FAIL_LINK;
1093 static void io_ring_ctx_ref_free(struct percpu_ref *ref)
1095 struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
1097 complete(&ctx->ref_comp);
1100 static inline bool io_is_timeout_noseq(struct io_kiocb *req)
1102 return !req->timeout.off;
1105 static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
1107 struct io_ring_ctx *ctx;
1110 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1115 * Use 5 bits less than the max cq entries, that should give us around
1116 * 32 entries per hash list if totally full and uniformly spread.
1118 hash_bits = ilog2(p->cq_entries);
1122 ctx->cancel_hash_bits = hash_bits;
1123 ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
1125 if (!ctx->cancel_hash)
1127 __hash_init(ctx->cancel_hash, 1U << hash_bits);
1129 if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
1130 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
1133 ctx->flags = p->flags;
1134 init_waitqueue_head(&ctx->sqo_sq_wait);
1135 INIT_LIST_HEAD(&ctx->sqd_list);
1136 init_waitqueue_head(&ctx->cq_wait);
1137 INIT_LIST_HEAD(&ctx->cq_overflow_list);
1138 init_completion(&ctx->ref_comp);
1139 init_completion(&ctx->sq_thread_comp);
1140 idr_init(&ctx->io_buffer_idr);
1141 xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
1142 mutex_init(&ctx->uring_lock);
1143 init_waitqueue_head(&ctx->wait);
1144 spin_lock_init(&ctx->completion_lock);
1145 INIT_LIST_HEAD(&ctx->iopoll_list);
1146 INIT_LIST_HEAD(&ctx->defer_list);
1147 INIT_LIST_HEAD(&ctx->timeout_list);
1148 spin_lock_init(&ctx->inflight_lock);
1149 INIT_LIST_HEAD(&ctx->inflight_list);
1150 spin_lock_init(&ctx->rsrc_ref_lock);
1151 INIT_LIST_HEAD(&ctx->rsrc_ref_list);
1152 INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
1153 init_llist_head(&ctx->rsrc_put_llist);
1154 INIT_LIST_HEAD(&ctx->tctx_list);
1155 INIT_LIST_HEAD(&ctx->submit_state.comp.free_list);
1156 INIT_LIST_HEAD(&ctx->submit_state.comp.locked_free_list);
1159 kfree(ctx->cancel_hash);
1164 static bool req_need_defer(struct io_kiocb *req, u32 seq)
1166 if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
1167 struct io_ring_ctx *ctx = req->ctx;
1169 return seq != ctx->cached_cq_tail
1170 + READ_ONCE(ctx->cached_cq_overflow);
1176 static void io_req_track_inflight(struct io_kiocb *req)
1178 struct io_ring_ctx *ctx = req->ctx;
1180 if (!(req->flags & REQ_F_INFLIGHT)) {
1181 req->flags |= REQ_F_INFLIGHT;
1183 spin_lock_irq(&ctx->inflight_lock);
1184 list_add(&req->inflight_entry, &ctx->inflight_list);
1185 spin_unlock_irq(&ctx->inflight_lock);
1189 static void io_prep_async_work(struct io_kiocb *req)
1191 const struct io_op_def *def = &io_op_defs[req->opcode];
1192 struct io_ring_ctx *ctx = req->ctx;
1194 if (!req->work.creds)
1195 req->work.creds = get_current_cred();
1197 if (req->flags & REQ_F_FORCE_ASYNC)
1198 req->work.flags |= IO_WQ_WORK_CONCURRENT;
1200 if (req->flags & REQ_F_ISREG) {
1201 if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
1202 io_wq_hash_work(&req->work, file_inode(req->file));
1204 if (def->unbound_nonreg_file)
1205 req->work.flags |= IO_WQ_WORK_UNBOUND;
1209 static void io_prep_async_link(struct io_kiocb *req)
1211 struct io_kiocb *cur;
1213 io_for_each_link(cur, req)
1214 io_prep_async_work(cur);
1217 static void io_queue_async_work(struct io_kiocb *req)
1219 struct io_ring_ctx *ctx = req->ctx;
1220 struct io_kiocb *link = io_prep_linked_timeout(req);
1221 struct io_uring_task *tctx = req->task->io_uring;
1224 BUG_ON(!tctx->io_wq);
1226 trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
1227 &req->work, req->flags);
1228 /* init ->work of the whole link before punting */
1229 io_prep_async_link(req);
1230 io_wq_enqueue(tctx->io_wq, &req->work);
1232 io_queue_linked_timeout(link);
1235 static void io_kill_timeout(struct io_kiocb *req)
1237 struct io_timeout_data *io = req->async_data;
1240 ret = hrtimer_try_to_cancel(&io->timer);
1242 atomic_set(&req->ctx->cq_timeouts,
1243 atomic_read(&req->ctx->cq_timeouts) + 1);
1244 list_del_init(&req->timeout.list);
1245 io_cqring_fill_event(req, 0);
1246 io_put_req_deferred(req, 1);
1251 * Returns true if we found and killed one or more timeouts
1253 static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
1254 struct files_struct *files)
1256 struct io_kiocb *req, *tmp;
1259 spin_lock_irq(&ctx->completion_lock);
1260 list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
1261 if (io_match_task(req, tsk, files)) {
1262 io_kill_timeout(req);
1266 spin_unlock_irq(&ctx->completion_lock);
1267 return canceled != 0;
1270 static void __io_queue_deferred(struct io_ring_ctx *ctx)
1273 struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
1274 struct io_defer_entry, list);
1276 if (req_need_defer(de->req, de->seq))
1278 list_del_init(&de->list);
1279 io_req_task_queue(de->req);
1281 } while (!list_empty(&ctx->defer_list));
1284 static void io_flush_timeouts(struct io_ring_ctx *ctx)
1288 if (list_empty(&ctx->timeout_list))
1291 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
1294 u32 events_needed, events_got;
1295 struct io_kiocb *req = list_first_entry(&ctx->timeout_list,
1296 struct io_kiocb, timeout.list);
1298 if (io_is_timeout_noseq(req))
1302 * Since seq can easily wrap around over time, subtract
1303 * the last seq at which timeouts were flushed before comparing.
1304 * Assuming not more than 2^31-1 events have happened since,
1305 * these subtractions won't have wrapped, so we can check if
1306 * target is in [last_seq, current_seq] by comparing the two.
1308 events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
1309 events_got = seq - ctx->cq_last_tm_flush;
1310 if (events_got < events_needed)
1313 list_del_init(&req->timeout.list);
1314 io_kill_timeout(req);
1315 } while (!list_empty(&ctx->timeout_list));
1317 ctx->cq_last_tm_flush = seq;
1320 static void io_commit_cqring(struct io_ring_ctx *ctx)
1322 io_flush_timeouts(ctx);
1324 /* order cqe stores with ring update */
1325 smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
1327 if (unlikely(!list_empty(&ctx->defer_list)))
1328 __io_queue_deferred(ctx);
1331 static inline bool io_sqring_full(struct io_ring_ctx *ctx)
1333 struct io_rings *r = ctx->rings;
1335 return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == r->sq_ring_entries;
1338 static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
1340 return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
1343 static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx)
1345 struct io_rings *rings = ctx->rings;
1349 * writes to the cq entry need to come after reading head; the
1350 * control dependency is enough as we're using WRITE_ONCE to
1353 if (__io_cqring_events(ctx) == rings->cq_ring_entries)
1356 tail = ctx->cached_cq_tail++;
1357 return &rings->cqes[tail & ctx->cq_mask];
1360 static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
1364 if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
1366 if (!ctx->eventfd_async)
1368 return io_wq_current_is_worker();
1371 static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
1373 /* see waitqueue_active() comment */
1376 if (waitqueue_active(&ctx->wait))
1377 wake_up(&ctx->wait);
1378 if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
1379 wake_up(&ctx->sq_data->wait);
1380 if (io_should_trigger_evfd(ctx))
1381 eventfd_signal(ctx->cq_ev_fd, 1);
1382 if (waitqueue_active(&ctx->cq_wait)) {
1383 wake_up_interruptible(&ctx->cq_wait);
1384 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
1388 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
1390 /* see waitqueue_active() comment */
1393 if (ctx->flags & IORING_SETUP_SQPOLL) {
1394 if (waitqueue_active(&ctx->wait))
1395 wake_up(&ctx->wait);
1397 if (io_should_trigger_evfd(ctx))
1398 eventfd_signal(ctx->cq_ev_fd, 1);
1399 if (waitqueue_active(&ctx->cq_wait)) {
1400 wake_up_interruptible(&ctx->cq_wait);
1401 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
1405 /* Returns true if there are no backlogged entries after the flush */
1406 static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
1407 struct task_struct *tsk,
1408 struct files_struct *files)
1410 struct io_rings *rings = ctx->rings;
1411 struct io_kiocb *req, *tmp;
1412 struct io_uring_cqe *cqe;
1413 unsigned long flags;
1414 bool all_flushed, posted;
1417 if (!force && __io_cqring_events(ctx) == rings->cq_ring_entries)
1421 spin_lock_irqsave(&ctx->completion_lock, flags);
1422 list_for_each_entry_safe(req, tmp, &ctx->cq_overflow_list, compl.list) {
1423 if (!io_match_task(req, tsk, files))
1426 cqe = io_get_cqring(ctx);
1430 list_move(&req->compl.list, &list);
1432 WRITE_ONCE(cqe->user_data, req->user_data);
1433 WRITE_ONCE(cqe->res, req->result);
1434 WRITE_ONCE(cqe->flags, req->compl.cflags);
1436 ctx->cached_cq_overflow++;
1437 WRITE_ONCE(ctx->rings->cq_overflow,
1438 ctx->cached_cq_overflow);
1443 all_flushed = list_empty(&ctx->cq_overflow_list);
1445 clear_bit(0, &ctx->sq_check_overflow);
1446 clear_bit(0, &ctx->cq_check_overflow);
1447 ctx->rings->sq_flags &= ~IORING_SQ_CQ_OVERFLOW;
1451 io_commit_cqring(ctx);
1452 spin_unlock_irqrestore(&ctx->completion_lock, flags);
1454 io_cqring_ev_posted(ctx);
1456 while (!list_empty(&list)) {
1457 req = list_first_entry(&list, struct io_kiocb, compl.list);
1458 list_del(&req->compl.list);
1465 static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force,
1466 struct task_struct *tsk,
1467 struct files_struct *files)
1471 if (test_bit(0, &ctx->cq_check_overflow)) {
1472 /* iopoll syncs against uring_lock, not completion_lock */
1473 if (ctx->flags & IORING_SETUP_IOPOLL)
1474 mutex_lock(&ctx->uring_lock);
1475 ret = __io_cqring_overflow_flush(ctx, force, tsk, files);
1476 if (ctx->flags & IORING_SETUP_IOPOLL)
1477 mutex_unlock(&ctx->uring_lock);
1483 static void __io_cqring_fill_event(struct io_kiocb *req, long res, long cflags)
1485 struct io_ring_ctx *ctx = req->ctx;
1486 struct io_uring_cqe *cqe;
1488 trace_io_uring_complete(ctx, req->user_data, res);
1491 * If we can't get a cq entry, userspace overflowed the
1492 * submission (by quite a lot). Increment the overflow count in
1495 cqe = io_get_cqring(ctx);
1497 WRITE_ONCE(cqe->user_data, req->user_data);
1498 WRITE_ONCE(cqe->res, res);
1499 WRITE_ONCE(cqe->flags, cflags);
1500 } else if (ctx->cq_overflow_flushed ||
1501 atomic_read(&req->task->io_uring->in_idle)) {
1503 * If we're in ring overflow flush mode, or in task cancel mode,
1504 * then we cannot store the request for later flushing, we need
1505 * to drop it on the floor.
1507 ctx->cached_cq_overflow++;
1508 WRITE_ONCE(ctx->rings->cq_overflow, ctx->cached_cq_overflow);
1510 if (list_empty(&ctx->cq_overflow_list)) {
1511 set_bit(0, &ctx->sq_check_overflow);
1512 set_bit(0, &ctx->cq_check_overflow);
1513 ctx->rings->sq_flags |= IORING_SQ_CQ_OVERFLOW;
1517 req->compl.cflags = cflags;
1518 refcount_inc(&req->refs);
1519 list_add_tail(&req->compl.list, &ctx->cq_overflow_list);
1523 static void io_cqring_fill_event(struct io_kiocb *req, long res)
1525 __io_cqring_fill_event(req, res, 0);
1528 static inline void io_req_complete_post(struct io_kiocb *req, long res,
1529 unsigned int cflags)
1531 struct io_ring_ctx *ctx = req->ctx;
1532 unsigned long flags;
1534 spin_lock_irqsave(&ctx->completion_lock, flags);
1535 __io_cqring_fill_event(req, res, cflags);
1536 io_commit_cqring(ctx);
1538 * If we're the last reference to this request, add to our locked
1541 if (refcount_dec_and_test(&req->refs)) {
1542 struct io_comp_state *cs = &ctx->submit_state.comp;
1544 io_dismantle_req(req);
1545 io_put_task(req->task, 1);
1546 list_add(&req->compl.list, &cs->locked_free_list);
1547 cs->locked_free_nr++;
1550 spin_unlock_irqrestore(&ctx->completion_lock, flags);
1552 io_cqring_ev_posted(ctx);
1555 percpu_ref_put(&ctx->refs);
1559 static void io_req_complete_state(struct io_kiocb *req, long res,
1560 unsigned int cflags)
1564 req->compl.cflags = cflags;
1565 req->flags |= REQ_F_COMPLETE_INLINE;
1568 static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
1569 long res, unsigned cflags)
1571 if (issue_flags & IO_URING_F_COMPLETE_DEFER)
1572 io_req_complete_state(req, res, cflags);
1574 io_req_complete_post(req, res, cflags);
1577 static inline void io_req_complete(struct io_kiocb *req, long res)
1579 __io_req_complete(req, 0, res, 0);
1582 static bool io_flush_cached_reqs(struct io_ring_ctx *ctx)
1584 struct io_submit_state *state = &ctx->submit_state;
1585 struct io_comp_state *cs = &state->comp;
1586 struct io_kiocb *req = NULL;
1589 * If we have more than a batch's worth of requests in our IRQ side
1590 * locked cache, grab the lock and move them over to our submission
1593 if (READ_ONCE(cs->locked_free_nr) > IO_COMPL_BATCH) {
1594 spin_lock_irq(&ctx->completion_lock);
1595 list_splice_init(&cs->locked_free_list, &cs->free_list);
1596 cs->locked_free_nr = 0;
1597 spin_unlock_irq(&ctx->completion_lock);
1600 while (!list_empty(&cs->free_list)) {
1601 req = list_first_entry(&cs->free_list, struct io_kiocb,
1603 list_del(&req->compl.list);
1604 state->reqs[state->free_reqs++] = req;
1605 if (state->free_reqs == ARRAY_SIZE(state->reqs))
1612 static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
1614 struct io_submit_state *state = &ctx->submit_state;
1616 BUILD_BUG_ON(IO_REQ_ALLOC_BATCH > ARRAY_SIZE(state->reqs));
1618 if (!state->free_reqs) {
1619 gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
1622 if (io_flush_cached_reqs(ctx))
1625 ret = kmem_cache_alloc_bulk(req_cachep, gfp, IO_REQ_ALLOC_BATCH,
1629 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1630 * retry single alloc to be on the safe side.
1632 if (unlikely(ret <= 0)) {
1633 state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
1634 if (!state->reqs[0])
1638 state->free_reqs = ret;
1642 return state->reqs[state->free_reqs];
1645 static inline void io_put_file(struct io_kiocb *req, struct file *file,
1652 static void io_dismantle_req(struct io_kiocb *req)
1656 if (req->async_data)
1657 kfree(req->async_data);
1659 io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE));
1660 if (req->fixed_rsrc_refs)
1661 percpu_ref_put(req->fixed_rsrc_refs);
1662 if (req->work.creds) {
1663 put_cred(req->work.creds);
1664 req->work.creds = NULL;
1667 if (req->flags & REQ_F_INFLIGHT) {
1668 struct io_ring_ctx *ctx = req->ctx;
1669 unsigned long flags;
1671 spin_lock_irqsave(&ctx->inflight_lock, flags);
1672 list_del(&req->inflight_entry);
1673 spin_unlock_irqrestore(&ctx->inflight_lock, flags);
1674 req->flags &= ~REQ_F_INFLIGHT;
1678 /* must to be called somewhat shortly after putting a request */
1679 static inline void io_put_task(struct task_struct *task, int nr)
1681 struct io_uring_task *tctx = task->io_uring;
1683 percpu_counter_sub(&tctx->inflight, nr);
1684 if (unlikely(atomic_read(&tctx->in_idle)))
1685 wake_up(&tctx->wait);
1686 put_task_struct_many(task, nr);
1689 static void __io_free_req(struct io_kiocb *req)
1691 struct io_ring_ctx *ctx = req->ctx;
1693 io_dismantle_req(req);
1694 io_put_task(req->task, 1);
1696 kmem_cache_free(req_cachep, req);
1697 percpu_ref_put(&ctx->refs);
1700 static inline void io_remove_next_linked(struct io_kiocb *req)
1702 struct io_kiocb *nxt = req->link;
1704 req->link = nxt->link;
1708 static bool io_kill_linked_timeout(struct io_kiocb *req)
1709 __must_hold(&req->ctx->completion_lock)
1711 struct io_kiocb *link = req->link;
1712 bool cancelled = false;
1715 * Can happen if a linked timeout fired and link had been like
1716 * req -> link t-out -> link t-out [-> ...]
1718 if (link && (link->flags & REQ_F_LTIMEOUT_ACTIVE)) {
1719 struct io_timeout_data *io = link->async_data;
1722 io_remove_next_linked(req);
1723 link->timeout.head = NULL;
1724 ret = hrtimer_try_to_cancel(&io->timer);
1726 io_cqring_fill_event(link, -ECANCELED);
1727 io_put_req_deferred(link, 1);
1731 req->flags &= ~REQ_F_LINK_TIMEOUT;
1735 static void io_fail_links(struct io_kiocb *req)
1736 __must_hold(&req->ctx->completion_lock)
1738 struct io_kiocb *nxt, *link = req->link;
1745 trace_io_uring_fail_link(req, link);
1746 io_cqring_fill_event(link, -ECANCELED);
1747 io_put_req_deferred(link, 2);
1752 static bool io_disarm_next(struct io_kiocb *req)
1753 __must_hold(&req->ctx->completion_lock)
1755 bool posted = false;
1757 if (likely(req->flags & REQ_F_LINK_TIMEOUT))
1758 posted = io_kill_linked_timeout(req);
1759 if (unlikely(req->flags & REQ_F_FAIL_LINK)) {
1760 posted |= (req->link != NULL);
1766 static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
1768 struct io_kiocb *nxt;
1771 * If LINK is set, we have dependent requests in this chain. If we
1772 * didn't fail this request, queue the first one up, moving any other
1773 * dependencies to the next request. In case of failure, fail the rest
1776 if (req->flags & (REQ_F_LINK_TIMEOUT | REQ_F_FAIL_LINK)) {
1777 struct io_ring_ctx *ctx = req->ctx;
1778 unsigned long flags;
1781 spin_lock_irqsave(&ctx->completion_lock, flags);
1782 posted = io_disarm_next(req);
1784 io_commit_cqring(req->ctx);
1785 spin_unlock_irqrestore(&ctx->completion_lock, flags);
1787 io_cqring_ev_posted(ctx);
1794 static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
1796 if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK))))
1798 return __io_req_find_next(req);
1801 static void ctx_flush_and_put(struct io_ring_ctx *ctx)
1805 if (ctx->submit_state.comp.nr) {
1806 mutex_lock(&ctx->uring_lock);
1807 io_submit_flush_completions(&ctx->submit_state.comp, ctx);
1808 mutex_unlock(&ctx->uring_lock);
1810 percpu_ref_put(&ctx->refs);
1813 static bool __tctx_task_work(struct io_uring_task *tctx)
1815 struct io_ring_ctx *ctx = NULL;
1816 struct io_wq_work_list list;
1817 struct io_wq_work_node *node;
1819 if (wq_list_empty(&tctx->task_list))
1822 spin_lock_irq(&tctx->task_lock);
1823 list = tctx->task_list;
1824 INIT_WQ_LIST(&tctx->task_list);
1825 spin_unlock_irq(&tctx->task_lock);
1829 struct io_wq_work_node *next = node->next;
1830 struct io_kiocb *req;
1832 req = container_of(node, struct io_kiocb, io_task_work.node);
1833 if (req->ctx != ctx) {
1834 ctx_flush_and_put(ctx);
1836 percpu_ref_get(&ctx->refs);
1839 req->task_work.func(&req->task_work);
1843 ctx_flush_and_put(ctx);
1844 return list.first != NULL;
1847 static void tctx_task_work(struct callback_head *cb)
1849 struct io_uring_task *tctx = container_of(cb, struct io_uring_task, task_work);
1851 clear_bit(0, &tctx->task_state);
1853 while (__tctx_task_work(tctx))
1857 static int io_task_work_add(struct task_struct *tsk, struct io_kiocb *req,
1858 enum task_work_notify_mode notify)
1860 struct io_uring_task *tctx = tsk->io_uring;
1861 struct io_wq_work_node *node, *prev;
1862 unsigned long flags;
1865 WARN_ON_ONCE(!tctx);
1867 spin_lock_irqsave(&tctx->task_lock, flags);
1868 wq_list_add_tail(&req->io_task_work.node, &tctx->task_list);
1869 spin_unlock_irqrestore(&tctx->task_lock, flags);
1871 /* task_work already pending, we're done */
1872 if (test_bit(0, &tctx->task_state) ||
1873 test_and_set_bit(0, &tctx->task_state))
1876 if (!task_work_add(tsk, &tctx->task_work, notify))
1880 * Slow path - we failed, find and delete work. if the work is not
1881 * in the list, it got run and we're fine.
1884 spin_lock_irqsave(&tctx->task_lock, flags);
1885 wq_list_for_each(node, prev, &tctx->task_list) {
1886 if (&req->io_task_work.node == node) {
1887 wq_list_del(&tctx->task_list, node, prev);
1892 spin_unlock_irqrestore(&tctx->task_lock, flags);
1893 clear_bit(0, &tctx->task_state);
1897 static int io_req_task_work_add(struct io_kiocb *req)
1899 struct task_struct *tsk = req->task;
1900 struct io_ring_ctx *ctx = req->ctx;
1901 enum task_work_notify_mode notify;
1904 if (tsk->flags & PF_EXITING)
1908 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
1909 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
1910 * processing task_work. There's no reliable way to tell if TWA_RESUME
1914 if (!(ctx->flags & IORING_SETUP_SQPOLL))
1915 notify = TWA_SIGNAL;
1917 ret = io_task_work_add(tsk, req, notify);
1919 wake_up_process(tsk);
1924 static void io_req_task_work_add_fallback(struct io_kiocb *req,
1925 task_work_func_t cb)
1927 struct io_ring_ctx *ctx = req->ctx;
1928 struct callback_head *head;
1930 init_task_work(&req->task_work, cb);
1932 head = READ_ONCE(ctx->exit_task_work);
1933 req->task_work.next = head;
1934 } while (cmpxchg(&ctx->exit_task_work, head, &req->task_work) != head);
1937 static void __io_req_task_cancel(struct io_kiocb *req, int error)
1939 struct io_ring_ctx *ctx = req->ctx;
1941 spin_lock_irq(&ctx->completion_lock);
1942 io_cqring_fill_event(req, error);
1943 io_commit_cqring(ctx);
1944 spin_unlock_irq(&ctx->completion_lock);
1946 io_cqring_ev_posted(ctx);
1947 req_set_fail_links(req);
1948 io_double_put_req(req);
1951 static void io_req_task_cancel(struct callback_head *cb)
1953 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
1954 struct io_ring_ctx *ctx = req->ctx;
1956 mutex_lock(&ctx->uring_lock);
1957 __io_req_task_cancel(req, req->result);
1958 mutex_unlock(&ctx->uring_lock);
1959 percpu_ref_put(&ctx->refs);
1962 static void __io_req_task_submit(struct io_kiocb *req)
1964 struct io_ring_ctx *ctx = req->ctx;
1966 /* ctx stays valid until unlock, even if we drop all ours ctx->refs */
1967 mutex_lock(&ctx->uring_lock);
1968 if (!(current->flags & PF_EXITING) && !current->in_execve)
1969 __io_queue_sqe(req);
1971 __io_req_task_cancel(req, -EFAULT);
1972 mutex_unlock(&ctx->uring_lock);
1975 static void io_req_task_submit(struct callback_head *cb)
1977 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
1979 __io_req_task_submit(req);
1982 static void io_req_task_queue(struct io_kiocb *req)
1986 req->task_work.func = io_req_task_submit;
1987 ret = io_req_task_work_add(req);
1988 if (unlikely(ret)) {
1989 req->result = -ECANCELED;
1990 percpu_ref_get(&req->ctx->refs);
1991 io_req_task_work_add_fallback(req, io_req_task_cancel);
1995 static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
1997 percpu_ref_get(&req->ctx->refs);
1999 req->task_work.func = io_req_task_cancel;
2001 if (unlikely(io_req_task_work_add(req)))
2002 io_req_task_work_add_fallback(req, io_req_task_cancel);
2005 static inline void io_queue_next(struct io_kiocb *req)
2007 struct io_kiocb *nxt = io_req_find_next(req);
2010 io_req_task_queue(nxt);
2013 static void io_free_req(struct io_kiocb *req)
2020 struct task_struct *task;
2025 static inline void io_init_req_batch(struct req_batch *rb)
2032 static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
2033 struct req_batch *rb)
2036 io_put_task(rb->task, rb->task_refs);
2038 percpu_ref_put_many(&ctx->refs, rb->ctx_refs);
2041 static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req,
2042 struct io_submit_state *state)
2046 if (req->task != rb->task) {
2048 io_put_task(rb->task, rb->task_refs);
2049 rb->task = req->task;
2055 io_dismantle_req(req);
2056 if (state->free_reqs != ARRAY_SIZE(state->reqs))
2057 state->reqs[state->free_reqs++] = req;
2059 list_add(&req->compl.list, &state->comp.free_list);
2062 static void io_submit_flush_completions(struct io_comp_state *cs,
2063 struct io_ring_ctx *ctx)
2066 struct io_kiocb *req;
2067 struct req_batch rb;
2069 io_init_req_batch(&rb);
2070 spin_lock_irq(&ctx->completion_lock);
2071 for (i = 0; i < nr; i++) {
2073 __io_cqring_fill_event(req, req->result, req->compl.cflags);
2075 io_commit_cqring(ctx);
2076 spin_unlock_irq(&ctx->completion_lock);
2078 io_cqring_ev_posted(ctx);
2079 for (i = 0; i < nr; i++) {
2082 /* submission and completion refs */
2083 if (refcount_sub_and_test(2, &req->refs))
2084 io_req_free_batch(&rb, req, &ctx->submit_state);
2087 io_req_free_batch_finish(ctx, &rb);
2092 * Drop reference to request, return next in chain (if there is one) if this
2093 * was the last reference to this request.
2095 static struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
2097 struct io_kiocb *nxt = NULL;
2099 if (refcount_dec_and_test(&req->refs)) {
2100 nxt = io_req_find_next(req);
2106 static void io_put_req(struct io_kiocb *req)
2108 if (refcount_dec_and_test(&req->refs))
2112 static void io_put_req_deferred_cb(struct callback_head *cb)
2114 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
2119 static void io_free_req_deferred(struct io_kiocb *req)
2123 req->task_work.func = io_put_req_deferred_cb;
2124 ret = io_req_task_work_add(req);
2126 io_req_task_work_add_fallback(req, io_put_req_deferred_cb);
2129 static inline void io_put_req_deferred(struct io_kiocb *req, int refs)
2131 if (refcount_sub_and_test(refs, &req->refs))
2132 io_free_req_deferred(req);
2135 static void io_double_put_req(struct io_kiocb *req)
2137 /* drop both submit and complete references */
2138 if (refcount_sub_and_test(2, &req->refs))
2142 static unsigned io_cqring_events(struct io_ring_ctx *ctx)
2144 /* See comment at the top of this file */
2146 return __io_cqring_events(ctx);
2149 static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
2151 struct io_rings *rings = ctx->rings;
2153 /* make sure SQ entry isn't read before tail */
2154 return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
2157 static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
2159 unsigned int cflags;
2161 cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
2162 cflags |= IORING_CQE_F_BUFFER;
2163 req->flags &= ~REQ_F_BUFFER_SELECTED;
2168 static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
2170 struct io_buffer *kbuf;
2172 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
2173 return io_put_kbuf(req, kbuf);
2176 static inline bool io_run_task_work(void)
2179 * Not safe to run on exiting task, and the task_work handling will
2180 * not add work to such a task.
2182 if (unlikely(current->flags & PF_EXITING))
2184 if (current->task_works) {
2185 __set_current_state(TASK_RUNNING);
2194 * Find and free completed poll iocbs
2196 static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
2197 struct list_head *done)
2199 struct req_batch rb;
2200 struct io_kiocb *req;
2202 /* order with ->result store in io_complete_rw_iopoll() */
2205 io_init_req_batch(&rb);
2206 while (!list_empty(done)) {
2209 req = list_first_entry(done, struct io_kiocb, inflight_entry);
2210 list_del(&req->inflight_entry);
2212 if (READ_ONCE(req->result) == -EAGAIN) {
2213 req->iopoll_completed = 0;
2214 if (io_rw_reissue(req))
2218 if (req->flags & REQ_F_BUFFER_SELECTED)
2219 cflags = io_put_rw_kbuf(req);
2221 __io_cqring_fill_event(req, req->result, cflags);
2224 if (refcount_dec_and_test(&req->refs))
2225 io_req_free_batch(&rb, req, &ctx->submit_state);
2228 io_commit_cqring(ctx);
2229 io_cqring_ev_posted_iopoll(ctx);
2230 io_req_free_batch_finish(ctx, &rb);
2233 static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
2236 struct io_kiocb *req, *tmp;
2242 * Only spin for completions if we don't have multiple devices hanging
2243 * off our complete list, and we're under the requested amount.
2245 spin = !ctx->poll_multi_file && *nr_events < min;
2248 list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
2249 struct kiocb *kiocb = &req->rw.kiocb;
2252 * Move completed and retryable entries to our local lists.
2253 * If we find a request that requires polling, break out
2254 * and complete those lists first, if we have entries there.
2256 if (READ_ONCE(req->iopoll_completed)) {
2257 list_move_tail(&req->inflight_entry, &done);
2260 if (!list_empty(&done))
2263 ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin);
2267 /* iopoll may have completed current req */
2268 if (READ_ONCE(req->iopoll_completed))
2269 list_move_tail(&req->inflight_entry, &done);
2276 if (!list_empty(&done))
2277 io_iopoll_complete(ctx, nr_events, &done);
2283 * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a
2284 * non-spinning poll check - we'll still enter the driver poll loop, but only
2285 * as a non-spinning completion check.
2287 static int io_iopoll_getevents(struct io_ring_ctx *ctx, unsigned int *nr_events,
2290 while (!list_empty(&ctx->iopoll_list) && !need_resched()) {
2293 ret = io_do_iopoll(ctx, nr_events, min);
2296 if (*nr_events >= min)
2304 * We can't just wait for polled events to come to us, we have to actively
2305 * find and complete them.
2307 static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
2309 if (!(ctx->flags & IORING_SETUP_IOPOLL))
2312 mutex_lock(&ctx->uring_lock);
2313 while (!list_empty(&ctx->iopoll_list)) {
2314 unsigned int nr_events = 0;
2316 io_do_iopoll(ctx, &nr_events, 0);
2318 /* let it sleep and repeat later if can't complete a request */
2322 * Ensure we allow local-to-the-cpu processing to take place,
2323 * in this case we need to ensure that we reap all events.
2324 * Also let task_work, etc. to progress by releasing the mutex
2326 if (need_resched()) {
2327 mutex_unlock(&ctx->uring_lock);
2329 mutex_lock(&ctx->uring_lock);
2332 mutex_unlock(&ctx->uring_lock);
2335 static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
2337 unsigned int nr_events = 0;
2338 int iters = 0, ret = 0;
2341 * We disallow the app entering submit/complete with polling, but we
2342 * still need to lock the ring to prevent racing with polled issue
2343 * that got punted to a workqueue.
2345 mutex_lock(&ctx->uring_lock);
2348 * Don't enter poll loop if we already have events pending.
2349 * If we do, we can potentially be spinning for commands that
2350 * already triggered a CQE (eg in error).
2352 if (test_bit(0, &ctx->cq_check_overflow))
2353 __io_cqring_overflow_flush(ctx, false, NULL, NULL);
2354 if (io_cqring_events(ctx))
2358 * If a submit got punted to a workqueue, we can have the
2359 * application entering polling for a command before it gets
2360 * issued. That app will hold the uring_lock for the duration
2361 * of the poll right here, so we need to take a breather every
2362 * now and then to ensure that the issue has a chance to add
2363 * the poll to the issued list. Otherwise we can spin here
2364 * forever, while the workqueue is stuck trying to acquire the
2367 if (!(++iters & 7)) {
2368 mutex_unlock(&ctx->uring_lock);
2370 mutex_lock(&ctx->uring_lock);
2373 ret = io_iopoll_getevents(ctx, &nr_events, min);
2377 } while (min && !nr_events && !need_resched());
2379 mutex_unlock(&ctx->uring_lock);
2383 static void kiocb_end_write(struct io_kiocb *req)
2386 * Tell lockdep we inherited freeze protection from submission
2389 if (req->flags & REQ_F_ISREG) {
2390 struct inode *inode = file_inode(req->file);
2392 __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE);
2394 file_end_write(req->file);
2398 static bool io_resubmit_prep(struct io_kiocb *req)
2400 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
2402 struct iov_iter iter;
2404 /* already prepared */
2405 if (req->async_data)
2408 switch (req->opcode) {
2409 case IORING_OP_READV:
2410 case IORING_OP_READ_FIXED:
2411 case IORING_OP_READ:
2414 case IORING_OP_WRITEV:
2415 case IORING_OP_WRITE_FIXED:
2416 case IORING_OP_WRITE:
2420 printk_once(KERN_WARNING "io_uring: bad opcode in resubmit %d\n",
2425 ret = io_import_iovec(rw, req, &iovec, &iter, false);
2428 return !io_setup_async_rw(req, iovec, inline_vecs, &iter, false);
2431 static bool io_rw_should_reissue(struct io_kiocb *req)
2433 umode_t mode = file_inode(req->file)->i_mode;
2434 struct io_ring_ctx *ctx = req->ctx;
2436 if (!S_ISBLK(mode) && !S_ISREG(mode))
2438 if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
2439 !(ctx->flags & IORING_SETUP_IOPOLL)))
2442 * If ref is dying, we might be running poll reap from the exit work.
2443 * Don't attempt to reissue from that path, just let it fail with
2446 if (percpu_ref_is_dying(&ctx->refs))
2452 static bool io_rw_reissue(struct io_kiocb *req)
2455 if (!io_rw_should_reissue(req))
2458 lockdep_assert_held(&req->ctx->uring_lock);
2460 if (io_resubmit_prep(req)) {
2461 refcount_inc(&req->refs);
2462 io_queue_async_work(req);
2465 req_set_fail_links(req);
2470 static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
2471 unsigned int issue_flags)
2475 if ((res == -EAGAIN || res == -EOPNOTSUPP) && io_rw_reissue(req))
2477 if (res != req->result)
2478 req_set_fail_links(req);
2480 if (req->rw.kiocb.ki_flags & IOCB_WRITE)
2481 kiocb_end_write(req);
2482 if (req->flags & REQ_F_BUFFER_SELECTED)
2483 cflags = io_put_rw_kbuf(req);
2484 __io_req_complete(req, issue_flags, res, cflags);
2487 static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
2489 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2491 __io_complete_rw(req, res, res2, 0);
2494 static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
2496 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2499 /* Rewind iter, if we have one. iopoll path resubmits as usual */
2500 if (res == -EAGAIN && io_rw_should_reissue(req)) {
2501 struct io_async_rw *rw = req->async_data;
2504 iov_iter_revert(&rw->iter,
2505 req->result - iov_iter_count(&rw->iter));
2506 else if (!io_resubmit_prep(req))
2511 if (kiocb->ki_flags & IOCB_WRITE)
2512 kiocb_end_write(req);
2514 if (res != -EAGAIN && res != req->result)
2515 req_set_fail_links(req);
2517 WRITE_ONCE(req->result, res);
2518 /* order with io_poll_complete() checking ->result */
2520 WRITE_ONCE(req->iopoll_completed, 1);
2524 * After the iocb has been issued, it's safe to be found on the poll list.
2525 * Adding the kiocb to the list AFTER submission ensures that we don't
2526 * find it from a io_iopoll_getevents() thread before the issuer is done
2527 * accessing the kiocb cookie.
2529 static void io_iopoll_req_issued(struct io_kiocb *req, bool in_async)
2531 struct io_ring_ctx *ctx = req->ctx;
2534 * Track whether we have multiple files in our lists. This will impact
2535 * how we do polling eventually, not spinning if we're on potentially
2536 * different devices.
2538 if (list_empty(&ctx->iopoll_list)) {
2539 ctx->poll_multi_file = false;
2540 } else if (!ctx->poll_multi_file) {
2541 struct io_kiocb *list_req;
2543 list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
2545 if (list_req->file != req->file)
2546 ctx->poll_multi_file = true;
2550 * For fast devices, IO may have already completed. If it has, add
2551 * it to the front so we find it first.
2553 if (READ_ONCE(req->iopoll_completed))
2554 list_add(&req->inflight_entry, &ctx->iopoll_list);
2556 list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
2559 * If IORING_SETUP_SQPOLL is enabled, sqes are either handled in sq thread
2560 * task context or in io worker task context. If current task context is
2561 * sq thread, we don't need to check whether should wake up sq thread.
2563 if (in_async && (ctx->flags & IORING_SETUP_SQPOLL) &&
2564 wq_has_sleeper(&ctx->sq_data->wait))
2565 wake_up(&ctx->sq_data->wait);
2568 static inline void io_state_file_put(struct io_submit_state *state)
2570 if (state->file_refs) {
2571 fput_many(state->file, state->file_refs);
2572 state->file_refs = 0;
2577 * Get as many references to a file as we have IOs left in this submission,
2578 * assuming most submissions are for one file, or at least that each file
2579 * has more than one submission.
2581 static struct file *__io_file_get(struct io_submit_state *state, int fd)
2586 if (state->file_refs) {
2587 if (state->fd == fd) {
2591 io_state_file_put(state);
2593 state->file = fget_many(fd, state->ios_left);
2594 if (unlikely(!state->file))
2598 state->file_refs = state->ios_left - 1;
2602 static bool io_bdev_nowait(struct block_device *bdev)
2604 return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
2608 * If we tracked the file through the SCM inflight mechanism, we could support
2609 * any file. For now, just ensure that anything potentially problematic is done
2612 static bool io_file_supports_async(struct file *file, int rw)
2614 umode_t mode = file_inode(file)->i_mode;
2616 if (S_ISBLK(mode)) {
2617 if (IS_ENABLED(CONFIG_BLOCK) &&
2618 io_bdev_nowait(I_BDEV(file->f_mapping->host)))
2622 if (S_ISCHR(mode) || S_ISSOCK(mode))
2624 if (S_ISREG(mode)) {
2625 if (IS_ENABLED(CONFIG_BLOCK) &&
2626 io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
2627 file->f_op != &io_uring_fops)
2632 /* any ->read/write should understand O_NONBLOCK */
2633 if (file->f_flags & O_NONBLOCK)
2636 if (!(file->f_mode & FMODE_NOWAIT))
2640 return file->f_op->read_iter != NULL;
2642 return file->f_op->write_iter != NULL;
2645 static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
2647 struct io_ring_ctx *ctx = req->ctx;
2648 struct kiocb *kiocb = &req->rw.kiocb;
2649 struct file *file = req->file;
2653 if (S_ISREG(file_inode(file)->i_mode))
2654 req->flags |= REQ_F_ISREG;
2656 kiocb->ki_pos = READ_ONCE(sqe->off);
2657 if (kiocb->ki_pos == -1 && !(file->f_mode & FMODE_STREAM)) {
2658 req->flags |= REQ_F_CUR_POS;
2659 kiocb->ki_pos = file->f_pos;
2661 kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
2662 kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
2663 ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
2667 /* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
2668 if ((kiocb->ki_flags & IOCB_NOWAIT) || (file->f_flags & O_NONBLOCK))
2669 req->flags |= REQ_F_NOWAIT;
2671 ioprio = READ_ONCE(sqe->ioprio);
2673 ret = ioprio_check_cap(ioprio);
2677 kiocb->ki_ioprio = ioprio;
2679 kiocb->ki_ioprio = get_current_ioprio();
2681 if (ctx->flags & IORING_SETUP_IOPOLL) {
2682 if (!(kiocb->ki_flags & IOCB_DIRECT) ||
2683 !kiocb->ki_filp->f_op->iopoll)
2686 kiocb->ki_flags |= IOCB_HIPRI;
2687 kiocb->ki_complete = io_complete_rw_iopoll;
2688 req->iopoll_completed = 0;
2690 if (kiocb->ki_flags & IOCB_HIPRI)
2692 kiocb->ki_complete = io_complete_rw;
2695 req->rw.addr = READ_ONCE(sqe->addr);
2696 req->rw.len = READ_ONCE(sqe->len);
2697 req->buf_index = READ_ONCE(sqe->buf_index);
2701 static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
2707 case -ERESTARTNOINTR:
2708 case -ERESTARTNOHAND:
2709 case -ERESTART_RESTARTBLOCK:
2711 * We can't just restart the syscall, since previously
2712 * submitted sqes may already be in progress. Just fail this
2718 kiocb->ki_complete(kiocb, ret, 0);
2722 static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
2723 unsigned int issue_flags)
2725 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2726 struct io_async_rw *io = req->async_data;
2728 /* add previously done IO, if any */
2729 if (io && io->bytes_done > 0) {
2731 ret = io->bytes_done;
2733 ret += io->bytes_done;
2736 if (req->flags & REQ_F_CUR_POS)
2737 req->file->f_pos = kiocb->ki_pos;
2738 if (ret >= 0 && kiocb->ki_complete == io_complete_rw)
2739 __io_complete_rw(req, ret, 0, issue_flags);
2741 io_rw_done(kiocb, ret);
2744 static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
2746 struct io_ring_ctx *ctx = req->ctx;
2747 size_t len = req->rw.len;
2748 struct io_mapped_ubuf *imu;
2749 u16 index, buf_index = req->buf_index;
2753 if (unlikely(buf_index >= ctx->nr_user_bufs))
2755 index = array_index_nospec(buf_index, ctx->nr_user_bufs);
2756 imu = &ctx->user_bufs[index];
2757 buf_addr = req->rw.addr;
2760 if (buf_addr + len < buf_addr)
2762 /* not inside the mapped region */
2763 if (buf_addr < imu->ubuf || buf_addr + len > imu->ubuf + imu->len)
2767 * May not be a start of buffer, set size appropriately
2768 * and advance us to the beginning.
2770 offset = buf_addr - imu->ubuf;
2771 iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
2775 * Don't use iov_iter_advance() here, as it's really slow for
2776 * using the latter parts of a big fixed buffer - it iterates
2777 * over each segment manually. We can cheat a bit here, because
2780 * 1) it's a BVEC iter, we set it up
2781 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2782 * first and last bvec
2784 * So just find our index, and adjust the iterator afterwards.
2785 * If the offset is within the first bvec (or the whole first
2786 * bvec, just use iov_iter_advance(). This makes it easier
2787 * since we can just skip the first segment, which may not
2788 * be PAGE_SIZE aligned.
2790 const struct bio_vec *bvec = imu->bvec;
2792 if (offset <= bvec->bv_len) {
2793 iov_iter_advance(iter, offset);
2795 unsigned long seg_skip;
2797 /* skip first vec */
2798 offset -= bvec->bv_len;
2799 seg_skip = 1 + (offset >> PAGE_SHIFT);
2801 iter->bvec = bvec + seg_skip;
2802 iter->nr_segs -= seg_skip;
2803 iter->count -= bvec->bv_len + offset;
2804 iter->iov_offset = offset & ~PAGE_MASK;
2811 static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
2814 mutex_unlock(&ctx->uring_lock);
2817 static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
2820 * "Normal" inline submissions always hold the uring_lock, since we
2821 * grab it from the system call. Same is true for the SQPOLL offload.
2822 * The only exception is when we've detached the request and issue it
2823 * from an async worker thread, grab the lock for that case.
2826 mutex_lock(&ctx->uring_lock);
2829 static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
2830 int bgid, struct io_buffer *kbuf,
2833 struct io_buffer *head;
2835 if (req->flags & REQ_F_BUFFER_SELECTED)
2838 io_ring_submit_lock(req->ctx, needs_lock);
2840 lockdep_assert_held(&req->ctx->uring_lock);
2842 head = idr_find(&req->ctx->io_buffer_idr, bgid);
2844 if (!list_empty(&head->list)) {
2845 kbuf = list_last_entry(&head->list, struct io_buffer,
2847 list_del(&kbuf->list);
2850 idr_remove(&req->ctx->io_buffer_idr, bgid);
2852 if (*len > kbuf->len)
2855 kbuf = ERR_PTR(-ENOBUFS);
2858 io_ring_submit_unlock(req->ctx, needs_lock);
2863 static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
2866 struct io_buffer *kbuf;
2869 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
2870 bgid = req->buf_index;
2871 kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
2874 req->rw.addr = (u64) (unsigned long) kbuf;
2875 req->flags |= REQ_F_BUFFER_SELECTED;
2876 return u64_to_user_ptr(kbuf->addr);
2879 #ifdef CONFIG_COMPAT
2880 static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
2883 struct compat_iovec __user *uiov;
2884 compat_ssize_t clen;
2888 uiov = u64_to_user_ptr(req->rw.addr);
2889 if (!access_ok(uiov, sizeof(*uiov)))
2891 if (__get_user(clen, &uiov->iov_len))
2897 buf = io_rw_buffer_select(req, &len, needs_lock);
2899 return PTR_ERR(buf);
2900 iov[0].iov_base = buf;
2901 iov[0].iov_len = (compat_size_t) len;
2906 static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
2909 struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
2913 if (copy_from_user(iov, uiov, sizeof(*uiov)))
2916 len = iov[0].iov_len;
2919 buf = io_rw_buffer_select(req, &len, needs_lock);
2921 return PTR_ERR(buf);
2922 iov[0].iov_base = buf;
2923 iov[0].iov_len = len;
2927 static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
2930 if (req->flags & REQ_F_BUFFER_SELECTED) {
2931 struct io_buffer *kbuf;
2933 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
2934 iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
2935 iov[0].iov_len = kbuf->len;
2938 if (req->rw.len != 1)
2941 #ifdef CONFIG_COMPAT
2942 if (req->ctx->compat)
2943 return io_compat_import(req, iov, needs_lock);
2946 return __io_iov_buffer_select(req, iov, needs_lock);
2949 static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
2950 struct iov_iter *iter, bool needs_lock)
2952 void __user *buf = u64_to_user_ptr(req->rw.addr);
2953 size_t sqe_len = req->rw.len;
2954 u8 opcode = req->opcode;
2957 if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
2959 return io_import_fixed(req, rw, iter);
2962 /* buffer index only valid with fixed read/write, or buffer select */
2963 if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
2966 if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
2967 if (req->flags & REQ_F_BUFFER_SELECT) {
2968 buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
2970 return PTR_ERR(buf);
2971 req->rw.len = sqe_len;
2974 ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
2979 if (req->flags & REQ_F_BUFFER_SELECT) {
2980 ret = io_iov_buffer_select(req, *iovec, needs_lock);
2982 iov_iter_init(iter, rw, *iovec, 1, (*iovec)->iov_len);
2987 return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
2991 static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
2993 return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
2997 * For files that don't have ->read_iter() and ->write_iter(), handle them
2998 * by looping over ->read() or ->write() manually.
3000 static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
3002 struct kiocb *kiocb = &req->rw.kiocb;
3003 struct file *file = req->file;
3007 * Don't support polled IO through this interface, and we can't
3008 * support non-blocking either. For the latter, this just causes
3009 * the kiocb to be handled from an async context.
3011 if (kiocb->ki_flags & IOCB_HIPRI)
3013 if (kiocb->ki_flags & IOCB_NOWAIT)
3016 while (iov_iter_count(iter)) {
3020 if (!iov_iter_is_bvec(iter)) {
3021 iovec = iov_iter_iovec(iter);
3023 iovec.iov_base = u64_to_user_ptr(req->rw.addr);
3024 iovec.iov_len = req->rw.len;
3028 nr = file->f_op->read(file, iovec.iov_base,
3029 iovec.iov_len, io_kiocb_ppos(kiocb));
3031 nr = file->f_op->write(file, iovec.iov_base,
3032 iovec.iov_len, io_kiocb_ppos(kiocb));
3041 if (nr != iovec.iov_len)
3045 iov_iter_advance(iter, nr);
3051 static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
3052 const struct iovec *fast_iov, struct iov_iter *iter)
3054 struct io_async_rw *rw = req->async_data;
3056 memcpy(&rw->iter, iter, sizeof(*iter));
3057 rw->free_iovec = iovec;
3059 /* can only be fixed buffers, no need to do anything */
3060 if (iov_iter_is_bvec(iter))
3063 unsigned iov_off = 0;
3065 rw->iter.iov = rw->fast_iov;
3066 if (iter->iov != fast_iov) {
3067 iov_off = iter->iov - fast_iov;
3068 rw->iter.iov += iov_off;
3070 if (rw->fast_iov != fast_iov)
3071 memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
3072 sizeof(struct iovec) * iter->nr_segs);
3074 req->flags |= REQ_F_NEED_CLEANUP;
3078 static inline int __io_alloc_async_data(struct io_kiocb *req)
3080 WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
3081 req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
3082 return req->async_data == NULL;
3085 static int io_alloc_async_data(struct io_kiocb *req)
3087 if (!io_op_defs[req->opcode].needs_async_data)
3090 return __io_alloc_async_data(req);
3093 static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
3094 const struct iovec *fast_iov,
3095 struct iov_iter *iter, bool force)
3097 if (!force && !io_op_defs[req->opcode].needs_async_data)
3099 if (!req->async_data) {
3100 if (__io_alloc_async_data(req)) {
3105 io_req_map_rw(req, iovec, fast_iov, iter);
3110 static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
3112 struct io_async_rw *iorw = req->async_data;
3113 struct iovec *iov = iorw->fast_iov;
3116 ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
3117 if (unlikely(ret < 0))
3120 iorw->bytes_done = 0;
3121 iorw->free_iovec = iov;
3123 req->flags |= REQ_F_NEED_CLEANUP;
3127 static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3129 if (unlikely(!(req->file->f_mode & FMODE_READ)))
3131 return io_prep_rw(req, sqe);
3135 * This is our waitqueue callback handler, registered through lock_page_async()
3136 * when we initially tried to do the IO with the iocb armed our waitqueue.
3137 * This gets called when the page is unlocked, and we generally expect that to
3138 * happen when the page IO is completed and the page is now uptodate. This will
3139 * queue a task_work based retry of the operation, attempting to copy the data
3140 * again. If the latter fails because the page was NOT uptodate, then we will
3141 * do a thread based blocking retry of the operation. That's the unexpected
3144 static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
3145 int sync, void *arg)
3147 struct wait_page_queue *wpq;
3148 struct io_kiocb *req = wait->private;
3149 struct wait_page_key *key = arg;
3151 wpq = container_of(wait, struct wait_page_queue, wait);
3153 if (!wake_page_match(wpq, key))
3156 req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
3157 list_del_init(&wait->entry);
3159 /* submit ref gets dropped, acquire a new one */
3160 refcount_inc(&req->refs);
3161 io_req_task_queue(req);
3166 * This controls whether a given IO request should be armed for async page
3167 * based retry. If we return false here, the request is handed to the async
3168 * worker threads for retry. If we're doing buffered reads on a regular file,
3169 * we prepare a private wait_page_queue entry and retry the operation. This
3170 * will either succeed because the page is now uptodate and unlocked, or it
3171 * will register a callback when the page is unlocked at IO completion. Through
3172 * that callback, io_uring uses task_work to setup a retry of the operation.
3173 * That retry will attempt the buffered read again. The retry will generally
3174 * succeed, or in rare cases where it fails, we then fall back to using the
3175 * async worker threads for a blocking retry.
3177 static bool io_rw_should_retry(struct io_kiocb *req)
3179 struct io_async_rw *rw = req->async_data;
3180 struct wait_page_queue *wait = &rw->wpq;
3181 struct kiocb *kiocb = &req->rw.kiocb;
3183 /* never retry for NOWAIT, we just complete with -EAGAIN */
3184 if (req->flags & REQ_F_NOWAIT)
3187 /* Only for buffered IO */
3188 if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
3192 * just use poll if we can, and don't attempt if the fs doesn't
3193 * support callback based unlocks
3195 if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
3198 wait->wait.func = io_async_buf_func;
3199 wait->wait.private = req;
3200 wait->wait.flags = 0;
3201 INIT_LIST_HEAD(&wait->wait.entry);
3202 kiocb->ki_flags |= IOCB_WAITQ;
3203 kiocb->ki_flags &= ~IOCB_NOWAIT;
3204 kiocb->ki_waitq = wait;
3208 static int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
3210 if (req->file->f_op->read_iter)
3211 return call_read_iter(req->file, &req->rw.kiocb, iter);
3212 else if (req->file->f_op->read)
3213 return loop_rw_iter(READ, req, iter);
3218 static int io_read(struct io_kiocb *req, unsigned int issue_flags)
3220 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
3221 struct kiocb *kiocb = &req->rw.kiocb;
3222 struct iov_iter __iter, *iter = &__iter;
3223 struct io_async_rw *rw = req->async_data;
3224 ssize_t io_size, ret, ret2;
3225 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3231 ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
3235 io_size = iov_iter_count(iter);
3236 req->result = io_size;
3238 /* Ensure we clear previously set non-block flag */
3239 if (!force_nonblock)
3240 kiocb->ki_flags &= ~IOCB_NOWAIT;
3242 kiocb->ki_flags |= IOCB_NOWAIT;
3244 /* If the file doesn't support async, just async punt */
3245 if (force_nonblock && !io_file_supports_async(req->file, READ)) {
3246 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
3247 return ret ?: -EAGAIN;
3250 ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), io_size);
3251 if (unlikely(ret)) {
3256 ret = io_iter_do_read(req, iter);
3258 if (ret == -EIOCBQUEUED) {
3259 if (req->async_data)
3260 iov_iter_revert(iter, io_size - iov_iter_count(iter));
3262 } else if (ret == -EAGAIN) {
3263 /* IOPOLL retry should happen for io-wq threads */
3264 if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
3266 /* no retry on NONBLOCK nor RWF_NOWAIT */
3267 if (req->flags & REQ_F_NOWAIT)
3269 /* some cases will consume bytes even on error returns */
3270 iov_iter_revert(iter, io_size - iov_iter_count(iter));
3272 } else if (ret <= 0 || ret == io_size || !force_nonblock ||
3273 (req->flags & REQ_F_NOWAIT) || !(req->flags & REQ_F_ISREG)) {
3274 /* read all, failed, already did sync or don't want to retry */
3278 ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
3283 rw = req->async_data;
3284 /* now use our persistent iterator, if we aren't already */
3289 rw->bytes_done += ret;
3290 /* if we can retry, do so with the callbacks armed */
3291 if (!io_rw_should_retry(req)) {
3292 kiocb->ki_flags &= ~IOCB_WAITQ;
3297 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3298 * we get -EIOCBQUEUED, then we'll get a notification when the
3299 * desired page gets unlocked. We can also get a partial read
3300 * here, and if we do, then just retry at the new offset.
3302 ret = io_iter_do_read(req, iter);
3303 if (ret == -EIOCBQUEUED)
3305 /* we got some bytes, but not all. retry. */
3306 kiocb->ki_flags &= ~IOCB_WAITQ;
3307 } while (ret > 0 && ret < io_size);
3309 kiocb_done(kiocb, ret, issue_flags);
3311 /* it's faster to check here then delegate to kfree */
3317 static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3319 if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
3321 return io_prep_rw(req, sqe);
3324 static int io_write(struct io_kiocb *req, unsigned int issue_flags)
3326 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
3327 struct kiocb *kiocb = &req->rw.kiocb;
3328 struct iov_iter __iter, *iter = &__iter;
3329 struct io_async_rw *rw = req->async_data;
3330 ssize_t ret, ret2, io_size;
3331 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3337 ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
3341 io_size = iov_iter_count(iter);
3342 req->result = io_size;
3344 /* Ensure we clear previously set non-block flag */
3345 if (!force_nonblock)
3346 kiocb->ki_flags &= ~IOCB_NOWAIT;
3348 kiocb->ki_flags |= IOCB_NOWAIT;
3350 /* If the file doesn't support async, just async punt */
3351 if (force_nonblock && !io_file_supports_async(req->file, WRITE))
3354 /* file path doesn't support NOWAIT for non-direct_IO */
3355 if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
3356 (req->flags & REQ_F_ISREG))
3359 ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), io_size);
3364 * Open-code file_start_write here to grab freeze protection,
3365 * which will be released by another thread in
3366 * io_complete_rw(). Fool lockdep by telling it the lock got
3367 * released so that it doesn't complain about the held lock when
3368 * we return to userspace.
3370 if (req->flags & REQ_F_ISREG) {
3371 sb_start_write(file_inode(req->file)->i_sb);
3372 __sb_writers_release(file_inode(req->file)->i_sb,
3375 kiocb->ki_flags |= IOCB_WRITE;
3377 if (req->file->f_op->write_iter)
3378 ret2 = call_write_iter(req->file, kiocb, iter);
3379 else if (req->file->f_op->write)
3380 ret2 = loop_rw_iter(WRITE, req, iter);
3385 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3386 * retry them without IOCB_NOWAIT.
3388 if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
3390 /* no retry on NONBLOCK nor RWF_NOWAIT */
3391 if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
3393 if (ret2 == -EIOCBQUEUED && req->async_data)
3394 iov_iter_revert(iter, io_size - iov_iter_count(iter));
3395 if (!force_nonblock || ret2 != -EAGAIN) {
3396 /* IOPOLL retry should happen for io-wq threads */
3397 if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
3400 kiocb_done(kiocb, ret2, issue_flags);
3403 /* some cases will consume bytes even on error returns */
3404 iov_iter_revert(iter, io_size - iov_iter_count(iter));
3405 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
3406 return ret ?: -EAGAIN;
3409 /* it's reportedly faster than delegating the null check to kfree() */
3415 static int io_renameat_prep(struct io_kiocb *req,
3416 const struct io_uring_sqe *sqe)
3418 struct io_rename *ren = &req->rename;
3419 const char __user *oldf, *newf;
3421 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3424 ren->old_dfd = READ_ONCE(sqe->fd);
3425 oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
3426 newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3427 ren->new_dfd = READ_ONCE(sqe->len);
3428 ren->flags = READ_ONCE(sqe->rename_flags);
3430 ren->oldpath = getname(oldf);
3431 if (IS_ERR(ren->oldpath))
3432 return PTR_ERR(ren->oldpath);
3434 ren->newpath = getname(newf);
3435 if (IS_ERR(ren->newpath)) {
3436 putname(ren->oldpath);
3437 return PTR_ERR(ren->newpath);
3440 req->flags |= REQ_F_NEED_CLEANUP;
3444 static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
3446 struct io_rename *ren = &req->rename;
3449 if (issue_flags & IO_URING_F_NONBLOCK)
3452 ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
3453 ren->newpath, ren->flags);
3455 req->flags &= ~REQ_F_NEED_CLEANUP;
3457 req_set_fail_links(req);
3458 io_req_complete(req, ret);
3462 static int io_unlinkat_prep(struct io_kiocb *req,
3463 const struct io_uring_sqe *sqe)
3465 struct io_unlink *un = &req->unlink;
3466 const char __user *fname;
3468 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3471 un->dfd = READ_ONCE(sqe->fd);
3473 un->flags = READ_ONCE(sqe->unlink_flags);
3474 if (un->flags & ~AT_REMOVEDIR)
3477 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
3478 un->filename = getname(fname);
3479 if (IS_ERR(un->filename))
3480 return PTR_ERR(un->filename);
3482 req->flags |= REQ_F_NEED_CLEANUP;
3486 static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
3488 struct io_unlink *un = &req->unlink;
3491 if (issue_flags & IO_URING_F_NONBLOCK)
3494 if (un->flags & AT_REMOVEDIR)
3495 ret = do_rmdir(un->dfd, un->filename);
3497 ret = do_unlinkat(un->dfd, un->filename);
3499 req->flags &= ~REQ_F_NEED_CLEANUP;
3501 req_set_fail_links(req);
3502 io_req_complete(req, ret);
3506 static int io_shutdown_prep(struct io_kiocb *req,
3507 const struct io_uring_sqe *sqe)
3509 #if defined(CONFIG_NET)
3510 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3512 if (sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags ||
3516 req->shutdown.how = READ_ONCE(sqe->len);
3523 static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
3525 #if defined(CONFIG_NET)
3526 struct socket *sock;
3529 if (issue_flags & IO_URING_F_NONBLOCK)
3532 sock = sock_from_file(req->file);
3533 if (unlikely(!sock))
3536 ret = __sys_shutdown_sock(sock, req->shutdown.how);
3538 req_set_fail_links(req);
3539 io_req_complete(req, ret);
3546 static int __io_splice_prep(struct io_kiocb *req,
3547 const struct io_uring_sqe *sqe)
3549 struct io_splice* sp = &req->splice;
3550 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
3552 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3556 sp->len = READ_ONCE(sqe->len);
3557 sp->flags = READ_ONCE(sqe->splice_flags);
3559 if (unlikely(sp->flags & ~valid_flags))
3562 sp->file_in = io_file_get(NULL, req, READ_ONCE(sqe->splice_fd_in),
3563 (sp->flags & SPLICE_F_FD_IN_FIXED));
3566 req->flags |= REQ_F_NEED_CLEANUP;
3568 if (!S_ISREG(file_inode(sp->file_in)->i_mode)) {
3570 * Splice operation will be punted aync, and here need to
3571 * modify io_wq_work.flags, so initialize io_wq_work firstly.
3573 req->work.flags |= IO_WQ_WORK_UNBOUND;
3579 static int io_tee_prep(struct io_kiocb *req,
3580 const struct io_uring_sqe *sqe)
3582 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
3584 return __io_splice_prep(req, sqe);
3587 static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
3589 struct io_splice *sp = &req->splice;
3590 struct file *in = sp->file_in;
3591 struct file *out = sp->file_out;
3592 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3595 if (issue_flags & IO_URING_F_NONBLOCK)
3598 ret = do_tee(in, out, sp->len, flags);
3600 io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED));
3601 req->flags &= ~REQ_F_NEED_CLEANUP;
3604 req_set_fail_links(req);
3605 io_req_complete(req, ret);
3609 static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3611 struct io_splice* sp = &req->splice;
3613 sp->off_in = READ_ONCE(sqe->splice_off_in);
3614 sp->off_out = READ_ONCE(sqe->off);
3615 return __io_splice_prep(req, sqe);
3618 static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
3620 struct io_splice *sp = &req->splice;
3621 struct file *in = sp->file_in;
3622 struct file *out = sp->file_out;
3623 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3624 loff_t *poff_in, *poff_out;
3627 if (issue_flags & IO_URING_F_NONBLOCK)
3630 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
3631 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
3634 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
3636 io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED));
3637 req->flags &= ~REQ_F_NEED_CLEANUP;
3640 req_set_fail_links(req);
3641 io_req_complete(req, ret);
3646 * IORING_OP_NOP just posts a completion event, nothing else.
3648 static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
3650 struct io_ring_ctx *ctx = req->ctx;
3652 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
3655 __io_req_complete(req, issue_flags, 0, 0);
3659 static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3661 struct io_ring_ctx *ctx = req->ctx;
3666 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
3668 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
3671 req->sync.flags = READ_ONCE(sqe->fsync_flags);
3672 if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
3675 req->sync.off = READ_ONCE(sqe->off);
3676 req->sync.len = READ_ONCE(sqe->len);
3680 static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
3682 loff_t end = req->sync.off + req->sync.len;
3685 /* fsync always requires a blocking context */
3686 if (issue_flags & IO_URING_F_NONBLOCK)
3689 ret = vfs_fsync_range(req->file, req->sync.off,
3690 end > 0 ? end : LLONG_MAX,
3691 req->sync.flags & IORING_FSYNC_DATASYNC);
3693 req_set_fail_links(req);
3694 io_req_complete(req, ret);
3698 static int io_fallocate_prep(struct io_kiocb *req,
3699 const struct io_uring_sqe *sqe)
3701 if (sqe->ioprio || sqe->buf_index || sqe->rw_flags)
3703 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3706 req->sync.off = READ_ONCE(sqe->off);
3707 req->sync.len = READ_ONCE(sqe->addr);
3708 req->sync.mode = READ_ONCE(sqe->len);
3712 static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
3716 /* fallocate always requiring blocking context */
3717 if (issue_flags & IO_URING_F_NONBLOCK)
3719 ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
3722 req_set_fail_links(req);
3723 io_req_complete(req, ret);
3727 static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3729 const char __user *fname;
3732 if (unlikely(sqe->ioprio || sqe->buf_index))
3734 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3737 /* open.how should be already initialised */
3738 if (!(req->open.how.flags & O_PATH) && force_o_largefile())
3739 req->open.how.flags |= O_LARGEFILE;
3741 req->open.dfd = READ_ONCE(sqe->fd);
3742 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
3743 req->open.filename = getname(fname);
3744 if (IS_ERR(req->open.filename)) {
3745 ret = PTR_ERR(req->open.filename);
3746 req->open.filename = NULL;
3749 req->open.nofile = rlimit(RLIMIT_NOFILE);
3750 req->flags |= REQ_F_NEED_CLEANUP;
3754 static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3758 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3760 mode = READ_ONCE(sqe->len);
3761 flags = READ_ONCE(sqe->open_flags);
3762 req->open.how = build_open_how(flags, mode);
3763 return __io_openat_prep(req, sqe);
3766 static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3768 struct open_how __user *how;
3772 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3774 how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3775 len = READ_ONCE(sqe->len);
3776 if (len < OPEN_HOW_SIZE_VER0)
3779 ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
3784 return __io_openat_prep(req, sqe);
3787 static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
3789 struct open_flags op;
3792 bool resolve_nonblock;
3795 ret = build_open_flags(&req->open.how, &op);
3798 nonblock_set = op.open_flag & O_NONBLOCK;
3799 resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
3800 if (issue_flags & IO_URING_F_NONBLOCK) {
3802 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
3803 * it'll always -EAGAIN
3805 if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
3807 op.lookup_flags |= LOOKUP_CACHED;
3808 op.open_flag |= O_NONBLOCK;
3811 ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
3815 file = do_filp_open(req->open.dfd, req->open.filename, &op);
3816 /* only retry if RESOLVE_CACHED wasn't already set by application */
3817 if ((!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)) &&
3818 file == ERR_PTR(-EAGAIN)) {
3820 * We could hang on to this 'fd', but seems like marginal
3821 * gain for something that is now known to be a slower path.
3822 * So just put it, and we'll get a new one when we retry.
3830 ret = PTR_ERR(file);
3832 if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
3833 file->f_flags &= ~O_NONBLOCK;
3834 fsnotify_open(file);
3835 fd_install(ret, file);
3838 putname(req->open.filename);
3839 req->flags &= ~REQ_F_NEED_CLEANUP;
3841 req_set_fail_links(req);
3842 io_req_complete(req, ret);
3846 static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
3848 return io_openat2(req, issue_flags);
3851 static int io_remove_buffers_prep(struct io_kiocb *req,
3852 const struct io_uring_sqe *sqe)
3854 struct io_provide_buf *p = &req->pbuf;
3857 if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off)
3860 tmp = READ_ONCE(sqe->fd);
3861 if (!tmp || tmp > USHRT_MAX)
3864 memset(p, 0, sizeof(*p));
3866 p->bgid = READ_ONCE(sqe->buf_group);
3870 static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
3871 int bgid, unsigned nbufs)
3875 /* shouldn't happen */
3879 /* the head kbuf is the list itself */
3880 while (!list_empty(&buf->list)) {
3881 struct io_buffer *nxt;
3883 nxt = list_first_entry(&buf->list, struct io_buffer, list);
3884 list_del(&nxt->list);
3891 idr_remove(&ctx->io_buffer_idr, bgid);
3896 static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
3898 struct io_provide_buf *p = &req->pbuf;
3899 struct io_ring_ctx *ctx = req->ctx;
3900 struct io_buffer *head;
3902 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3904 io_ring_submit_lock(ctx, !force_nonblock);
3906 lockdep_assert_held(&ctx->uring_lock);
3909 head = idr_find(&ctx->io_buffer_idr, p->bgid);
3911 ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
3913 req_set_fail_links(req);
3915 /* need to hold the lock to complete IOPOLL requests */
3916 if (ctx->flags & IORING_SETUP_IOPOLL) {
3917 __io_req_complete(req, issue_flags, ret, 0);
3918 io_ring_submit_unlock(ctx, !force_nonblock);
3920 io_ring_submit_unlock(ctx, !force_nonblock);
3921 __io_req_complete(req, issue_flags, ret, 0);
3926 static int io_provide_buffers_prep(struct io_kiocb *req,
3927 const struct io_uring_sqe *sqe)
3929 struct io_provide_buf *p = &req->pbuf;
3932 if (sqe->ioprio || sqe->rw_flags)
3935 tmp = READ_ONCE(sqe->fd);
3936 if (!tmp || tmp > USHRT_MAX)
3939 p->addr = READ_ONCE(sqe->addr);
3940 p->len = READ_ONCE(sqe->len);
3942 if (!access_ok(u64_to_user_ptr(p->addr), (p->len * p->nbufs)))
3945 p->bgid = READ_ONCE(sqe->buf_group);
3946 tmp = READ_ONCE(sqe->off);
3947 if (tmp > USHRT_MAX)
3953 static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
3955 struct io_buffer *buf;
3956 u64 addr = pbuf->addr;
3957 int i, bid = pbuf->bid;
3959 for (i = 0; i < pbuf->nbufs; i++) {
3960 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
3965 buf->len = pbuf->len;
3970 INIT_LIST_HEAD(&buf->list);
3973 list_add_tail(&buf->list, &(*head)->list);
3977 return i ? i : -ENOMEM;
3980 static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
3982 struct io_provide_buf *p = &req->pbuf;
3983 struct io_ring_ctx *ctx = req->ctx;
3984 struct io_buffer *head, *list;
3986 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3988 io_ring_submit_lock(ctx, !force_nonblock);
3990 lockdep_assert_held(&ctx->uring_lock);
3992 list = head = idr_find(&ctx->io_buffer_idr, p->bgid);
3994 ret = io_add_buffers(p, &head);
3999 ret = idr_alloc(&ctx->io_buffer_idr, head, p->bgid, p->bgid + 1,
4002 __io_remove_buffers(ctx, head, p->bgid, -1U);
4008 req_set_fail_links(req);
4010 /* need to hold the lock to complete IOPOLL requests */
4011 if (ctx->flags & IORING_SETUP_IOPOLL) {
4012 __io_req_complete(req, issue_flags, ret, 0);
4013 io_ring_submit_unlock(ctx, !force_nonblock);
4015 io_ring_submit_unlock(ctx, !force_nonblock);
4016 __io_req_complete(req, issue_flags, ret, 0);
4021 static int io_epoll_ctl_prep(struct io_kiocb *req,
4022 const struct io_uring_sqe *sqe)
4024 #if defined(CONFIG_EPOLL)
4025 if (sqe->ioprio || sqe->buf_index)
4027 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL)))
4030 req->epoll.epfd = READ_ONCE(sqe->fd);
4031 req->epoll.op = READ_ONCE(sqe->len);
4032 req->epoll.fd = READ_ONCE(sqe->off);
4034 if (ep_op_has_event(req->epoll.op)) {
4035 struct epoll_event __user *ev;
4037 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
4038 if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
4048 static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
4050 #if defined(CONFIG_EPOLL)
4051 struct io_epoll *ie = &req->epoll;
4053 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4055 ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
4056 if (force_nonblock && ret == -EAGAIN)
4060 req_set_fail_links(req);
4061 __io_req_complete(req, issue_flags, ret, 0);
4068 static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4070 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4071 if (sqe->ioprio || sqe->buf_index || sqe->off)
4073 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4076 req->madvise.addr = READ_ONCE(sqe->addr);
4077 req->madvise.len = READ_ONCE(sqe->len);
4078 req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
4085 static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
4087 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4088 struct io_madvise *ma = &req->madvise;
4091 if (issue_flags & IO_URING_F_NONBLOCK)
4094 ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
4096 req_set_fail_links(req);
4097 io_req_complete(req, ret);
4104 static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4106 if (sqe->ioprio || sqe->buf_index || sqe->addr)
4108 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4111 req->fadvise.offset = READ_ONCE(sqe->off);
4112 req->fadvise.len = READ_ONCE(sqe->len);
4113 req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
4117 static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
4119 struct io_fadvise *fa = &req->fadvise;
4122 if (issue_flags & IO_URING_F_NONBLOCK) {
4123 switch (fa->advice) {
4124 case POSIX_FADV_NORMAL:
4125 case POSIX_FADV_RANDOM:
4126 case POSIX_FADV_SEQUENTIAL:
4133 ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
4135 req_set_fail_links(req);
4136 io_req_complete(req, ret);
4140 static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4142 if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL)))
4144 if (sqe->ioprio || sqe->buf_index)
4146 if (req->flags & REQ_F_FIXED_FILE)
4149 req->statx.dfd = READ_ONCE(sqe->fd);
4150 req->statx.mask = READ_ONCE(sqe->len);
4151 req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
4152 req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4153 req->statx.flags = READ_ONCE(sqe->statx_flags);
4158 static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
4160 struct io_statx *ctx = &req->statx;
4163 if (issue_flags & IO_URING_F_NONBLOCK) {
4164 /* only need file table for an actual valid fd */
4165 if (ctx->dfd == -1 || ctx->dfd == AT_FDCWD)
4166 req->flags |= REQ_F_NO_FILE_TABLE;
4170 ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
4174 req_set_fail_links(req);
4175 io_req_complete(req, ret);
4179 static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4181 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4183 if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
4184 sqe->rw_flags || sqe->buf_index)
4186 if (req->flags & REQ_F_FIXED_FILE)
4189 req->close.fd = READ_ONCE(sqe->fd);
4193 static int io_close(struct io_kiocb *req, unsigned int issue_flags)
4195 struct files_struct *files = current->files;
4196 struct io_close *close = &req->close;
4197 struct fdtable *fdt;
4203 spin_lock(&files->file_lock);
4204 fdt = files_fdtable(files);
4205 if (close->fd >= fdt->max_fds) {
4206 spin_unlock(&files->file_lock);
4209 file = fdt->fd[close->fd];
4211 spin_unlock(&files->file_lock);
4215 if (file->f_op == &io_uring_fops) {
4216 spin_unlock(&files->file_lock);
4221 /* if the file has a flush method, be safe and punt to async */
4222 if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
4223 spin_unlock(&files->file_lock);
4227 ret = __close_fd_get_file(close->fd, &file);
4228 spin_unlock(&files->file_lock);
4235 /* No ->flush() or already async, safely close from here */
4236 ret = filp_close(file, current->files);
4239 req_set_fail_links(req);
4242 __io_req_complete(req, issue_flags, ret, 0);
4246 static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4248 struct io_ring_ctx *ctx = req->ctx;
4250 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
4252 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
4255 req->sync.off = READ_ONCE(sqe->off);
4256 req->sync.len = READ_ONCE(sqe->len);
4257 req->sync.flags = READ_ONCE(sqe->sync_range_flags);
4261 static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
4265 /* sync_file_range always requires a blocking context */
4266 if (issue_flags & IO_URING_F_NONBLOCK)
4269 ret = sync_file_range(req->file, req->sync.off, req->sync.len,
4272 req_set_fail_links(req);
4273 io_req_complete(req, ret);
4277 #if defined(CONFIG_NET)
4278 static int io_setup_async_msg(struct io_kiocb *req,
4279 struct io_async_msghdr *kmsg)
4281 struct io_async_msghdr *async_msg = req->async_data;
4285 if (io_alloc_async_data(req)) {
4286 kfree(kmsg->free_iov);
4289 async_msg = req->async_data;
4290 req->flags |= REQ_F_NEED_CLEANUP;
4291 memcpy(async_msg, kmsg, sizeof(*kmsg));
4292 async_msg->msg.msg_name = &async_msg->addr;
4293 /* if were using fast_iov, set it to the new one */
4294 if (!async_msg->free_iov)
4295 async_msg->msg.msg_iter.iov = async_msg->fast_iov;
4300 static int io_sendmsg_copy_hdr(struct io_kiocb *req,
4301 struct io_async_msghdr *iomsg)
4303 iomsg->msg.msg_name = &iomsg->addr;
4304 iomsg->free_iov = iomsg->fast_iov;
4305 return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
4306 req->sr_msg.msg_flags, &iomsg->free_iov);
4309 static int io_sendmsg_prep_async(struct io_kiocb *req)
4313 if (!io_op_defs[req->opcode].needs_async_data)
4315 ret = io_sendmsg_copy_hdr(req, req->async_data);
4317 req->flags |= REQ_F_NEED_CLEANUP;
4321 static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4323 struct io_sr_msg *sr = &req->sr_msg;
4325 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4328 sr->msg_flags = READ_ONCE(sqe->msg_flags);
4329 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
4330 sr->len = READ_ONCE(sqe->len);
4332 #ifdef CONFIG_COMPAT
4333 if (req->ctx->compat)
4334 sr->msg_flags |= MSG_CMSG_COMPAT;
4339 static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
4341 struct io_async_msghdr iomsg, *kmsg;
4342 struct socket *sock;
4346 sock = sock_from_file(req->file);
4347 if (unlikely(!sock))
4350 kmsg = req->async_data;
4352 ret = io_sendmsg_copy_hdr(req, &iomsg);
4358 flags = req->sr_msg.msg_flags;
4359 if (flags & MSG_DONTWAIT)
4360 req->flags |= REQ_F_NOWAIT;
4361 else if (issue_flags & IO_URING_F_NONBLOCK)
4362 flags |= MSG_DONTWAIT;
4364 ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
4365 if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
4366 return io_setup_async_msg(req, kmsg);
4367 if (ret == -ERESTARTSYS)
4370 /* fast path, check for non-NULL to avoid function call */
4372 kfree(kmsg->free_iov);
4373 req->flags &= ~REQ_F_NEED_CLEANUP;
4375 req_set_fail_links(req);
4376 __io_req_complete(req, issue_flags, ret, 0);
4380 static int io_send(struct io_kiocb *req, unsigned int issue_flags)
4382 struct io_sr_msg *sr = &req->sr_msg;
4385 struct socket *sock;
4389 sock = sock_from_file(req->file);
4390 if (unlikely(!sock))
4393 ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
4397 msg.msg_name = NULL;
4398 msg.msg_control = NULL;
4399 msg.msg_controllen = 0;
4400 msg.msg_namelen = 0;
4402 flags = req->sr_msg.msg_flags;
4403 if (flags & MSG_DONTWAIT)
4404 req->flags |= REQ_F_NOWAIT;
4405 else if (issue_flags & IO_URING_F_NONBLOCK)
4406 flags |= MSG_DONTWAIT;
4408 msg.msg_flags = flags;
4409 ret = sock_sendmsg(sock, &msg);
4410 if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
4412 if (ret == -ERESTARTSYS)
4416 req_set_fail_links(req);
4417 __io_req_complete(req, issue_flags, ret, 0);
4421 static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
4422 struct io_async_msghdr *iomsg)
4424 struct io_sr_msg *sr = &req->sr_msg;
4425 struct iovec __user *uiov;
4429 ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
4430 &iomsg->uaddr, &uiov, &iov_len);
4434 if (req->flags & REQ_F_BUFFER_SELECT) {
4437 if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
4439 sr->len = iomsg->fast_iov[0].iov_len;
4440 iomsg->free_iov = NULL;
4442 iomsg->free_iov = iomsg->fast_iov;
4443 ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
4444 &iomsg->free_iov, &iomsg->msg.msg_iter,
4453 #ifdef CONFIG_COMPAT
4454 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
4455 struct io_async_msghdr *iomsg)
4457 struct compat_msghdr __user *msg_compat;
4458 struct io_sr_msg *sr = &req->sr_msg;
4459 struct compat_iovec __user *uiov;
4464 msg_compat = (struct compat_msghdr __user *) sr->umsg;
4465 ret = __get_compat_msghdr(&iomsg->msg, msg_compat, &iomsg->uaddr,
4470 uiov = compat_ptr(ptr);
4471 if (req->flags & REQ_F_BUFFER_SELECT) {
4472 compat_ssize_t clen;
4476 if (!access_ok(uiov, sizeof(*uiov)))
4478 if (__get_user(clen, &uiov->iov_len))
4483 iomsg->free_iov = NULL;
4485 iomsg->free_iov = iomsg->fast_iov;
4486 ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
4487 UIO_FASTIOV, &iomsg->free_iov,
4488 &iomsg->msg.msg_iter, true);
4497 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
4498 struct io_async_msghdr *iomsg)
4500 iomsg->msg.msg_name = &iomsg->addr;
4502 #ifdef CONFIG_COMPAT
4503 if (req->ctx->compat)
4504 return __io_compat_recvmsg_copy_hdr(req, iomsg);
4507 return __io_recvmsg_copy_hdr(req, iomsg);
4510 static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
4513 struct io_sr_msg *sr = &req->sr_msg;
4514 struct io_buffer *kbuf;
4516 kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
4521 req->flags |= REQ_F_BUFFER_SELECTED;
4525 static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
4527 return io_put_kbuf(req, req->sr_msg.kbuf);
4530 static int io_recvmsg_prep_async(struct io_kiocb *req)
4534 if (!io_op_defs[req->opcode].needs_async_data)
4536 ret = io_recvmsg_copy_hdr(req, req->async_data);
4538 req->flags |= REQ_F_NEED_CLEANUP;
4542 static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4544 struct io_sr_msg *sr = &req->sr_msg;
4546 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4549 sr->msg_flags = READ_ONCE(sqe->msg_flags);
4550 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
4551 sr->len = READ_ONCE(sqe->len);
4552 sr->bgid = READ_ONCE(sqe->buf_group);
4554 #ifdef CONFIG_COMPAT
4555 if (req->ctx->compat)
4556 sr->msg_flags |= MSG_CMSG_COMPAT;
4561 static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
4563 struct io_async_msghdr iomsg, *kmsg;
4564 struct socket *sock;
4565 struct io_buffer *kbuf;
4567 int ret, cflags = 0;
4568 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4570 sock = sock_from_file(req->file);
4571 if (unlikely(!sock))
4574 kmsg = req->async_data;
4576 ret = io_recvmsg_copy_hdr(req, &iomsg);
4582 if (req->flags & REQ_F_BUFFER_SELECT) {
4583 kbuf = io_recv_buffer_select(req, !force_nonblock);
4585 return PTR_ERR(kbuf);
4586 kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
4587 kmsg->fast_iov[0].iov_len = req->sr_msg.len;
4588 iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov,
4589 1, req->sr_msg.len);
4592 flags = req->sr_msg.msg_flags;
4593 if (flags & MSG_DONTWAIT)
4594 req->flags |= REQ_F_NOWAIT;
4595 else if (force_nonblock)
4596 flags |= MSG_DONTWAIT;
4598 ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
4599 kmsg->uaddr, flags);
4600 if (force_nonblock && ret == -EAGAIN)
4601 return io_setup_async_msg(req, kmsg);
4602 if (ret == -ERESTARTSYS)
4605 if (req->flags & REQ_F_BUFFER_SELECTED)
4606 cflags = io_put_recv_kbuf(req);
4607 /* fast path, check for non-NULL to avoid function call */
4609 kfree(kmsg->free_iov);
4610 req->flags &= ~REQ_F_NEED_CLEANUP;
4612 req_set_fail_links(req);
4613 __io_req_complete(req, issue_flags, ret, cflags);
4617 static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
4619 struct io_buffer *kbuf;
4620 struct io_sr_msg *sr = &req->sr_msg;
4622 void __user *buf = sr->buf;
4623 struct socket *sock;
4626 int ret, cflags = 0;
4627 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4629 sock = sock_from_file(req->file);
4630 if (unlikely(!sock))
4633 if (req->flags & REQ_F_BUFFER_SELECT) {
4634 kbuf = io_recv_buffer_select(req, !force_nonblock);
4636 return PTR_ERR(kbuf);
4637 buf = u64_to_user_ptr(kbuf->addr);
4640 ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
4644 msg.msg_name = NULL;
4645 msg.msg_control = NULL;
4646 msg.msg_controllen = 0;
4647 msg.msg_namelen = 0;
4648 msg.msg_iocb = NULL;
4651 flags = req->sr_msg.msg_flags;
4652 if (flags & MSG_DONTWAIT)
4653 req->flags |= REQ_F_NOWAIT;
4654 else if (force_nonblock)
4655 flags |= MSG_DONTWAIT;
4657 ret = sock_recvmsg(sock, &msg, flags);
4658 if (force_nonblock && ret == -EAGAIN)
4660 if (ret == -ERESTARTSYS)
4663 if (req->flags & REQ_F_BUFFER_SELECTED)
4664 cflags = io_put_recv_kbuf(req);
4666 req_set_fail_links(req);
4667 __io_req_complete(req, issue_flags, ret, cflags);
4671 static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4673 struct io_accept *accept = &req->accept;
4675 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4677 if (sqe->ioprio || sqe->len || sqe->buf_index)
4680 accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
4681 accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4682 accept->flags = READ_ONCE(sqe->accept_flags);
4683 accept->nofile = rlimit(RLIMIT_NOFILE);
4687 static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
4689 struct io_accept *accept = &req->accept;
4690 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4691 unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
4694 if (req->file->f_flags & O_NONBLOCK)
4695 req->flags |= REQ_F_NOWAIT;
4697 ret = __sys_accept4_file(req->file, file_flags, accept->addr,
4698 accept->addr_len, accept->flags,
4700 if (ret == -EAGAIN && force_nonblock)
4703 if (ret == -ERESTARTSYS)
4705 req_set_fail_links(req);
4707 __io_req_complete(req, issue_flags, ret, 0);
4711 static int io_connect_prep_async(struct io_kiocb *req)
4713 struct io_async_connect *io = req->async_data;
4714 struct io_connect *conn = &req->connect;
4716 return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
4719 static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4721 struct io_connect *conn = &req->connect;
4723 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4725 if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags)
4728 conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
4729 conn->addr_len = READ_ONCE(sqe->addr2);
4733 static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
4735 struct io_async_connect __io, *io;
4736 unsigned file_flags;
4738 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4740 if (req->async_data) {
4741 io = req->async_data;
4743 ret = move_addr_to_kernel(req->connect.addr,
4744 req->connect.addr_len,
4751 file_flags = force_nonblock ? O_NONBLOCK : 0;
4753 ret = __sys_connect_file(req->file, &io->address,
4754 req->connect.addr_len, file_flags);
4755 if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
4756 if (req->async_data)
4758 if (io_alloc_async_data(req)) {
4762 io = req->async_data;
4763 memcpy(req->async_data, &__io, sizeof(__io));
4766 if (ret == -ERESTARTSYS)
4770 req_set_fail_links(req);
4771 __io_req_complete(req, issue_flags, ret, 0);
4774 #else /* !CONFIG_NET */
4775 #define IO_NETOP_FN(op) \
4776 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
4778 return -EOPNOTSUPP; \
4781 #define IO_NETOP_PREP(op) \
4783 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
4785 return -EOPNOTSUPP; \
4788 #define IO_NETOP_PREP_ASYNC(op) \
4790 static int io_##op##_prep_async(struct io_kiocb *req) \
4792 return -EOPNOTSUPP; \
4795 IO_NETOP_PREP_ASYNC(sendmsg);
4796 IO_NETOP_PREP_ASYNC(recvmsg);
4797 IO_NETOP_PREP_ASYNC(connect);
4798 IO_NETOP_PREP(accept);
4801 #endif /* CONFIG_NET */
4803 struct io_poll_table {
4804 struct poll_table_struct pt;
4805 struct io_kiocb *req;
4809 static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll,
4810 __poll_t mask, task_work_func_t func)
4814 /* for instances that support it check for an event match first: */
4815 if (mask && !(mask & poll->events))
4818 trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
4820 list_del_init(&poll->wait.entry);
4823 req->task_work.func = func;
4824 percpu_ref_get(&req->ctx->refs);
4827 * If this fails, then the task is exiting. When a task exits, the
4828 * work gets canceled, so just cancel this request as well instead
4829 * of executing it. We can't safely execute it anyway, as we may not
4830 * have the needed state needed for it anyway.
4832 ret = io_req_task_work_add(req);
4833 if (unlikely(ret)) {
4834 WRITE_ONCE(poll->canceled, true);
4835 io_req_task_work_add_fallback(req, func);
4840 static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
4841 __acquires(&req->ctx->completion_lock)
4843 struct io_ring_ctx *ctx = req->ctx;
4845 if (!req->result && !READ_ONCE(poll->canceled)) {
4846 struct poll_table_struct pt = { ._key = poll->events };
4848 req->result = vfs_poll(req->file, &pt) & poll->events;
4851 spin_lock_irq(&ctx->completion_lock);
4852 if (!req->result && !READ_ONCE(poll->canceled)) {
4853 add_wait_queue(poll->head, &poll->wait);
4860 static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
4862 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
4863 if (req->opcode == IORING_OP_POLL_ADD)
4864 return req->async_data;
4865 return req->apoll->double_poll;
4868 static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
4870 if (req->opcode == IORING_OP_POLL_ADD)
4872 return &req->apoll->poll;
4875 static void io_poll_remove_double(struct io_kiocb *req)
4877 struct io_poll_iocb *poll = io_poll_get_double(req);
4879 lockdep_assert_held(&req->ctx->completion_lock);
4881 if (poll && poll->head) {
4882 struct wait_queue_head *head = poll->head;
4884 spin_lock(&head->lock);
4885 list_del_init(&poll->wait.entry);
4886 if (poll->wait.private)
4887 refcount_dec(&req->refs);
4889 spin_unlock(&head->lock);
4893 static void io_poll_complete(struct io_kiocb *req, __poll_t mask, int error)
4895 struct io_ring_ctx *ctx = req->ctx;
4897 io_poll_remove_double(req);
4898 req->poll.done = true;
4899 io_cqring_fill_event(req, error ? error : mangle_poll(mask));
4900 io_commit_cqring(ctx);
4903 static void io_poll_task_func(struct callback_head *cb)
4905 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
4906 struct io_ring_ctx *ctx = req->ctx;
4907 struct io_kiocb *nxt;
4909 if (io_poll_rewait(req, &req->poll)) {
4910 spin_unlock_irq(&ctx->completion_lock);
4912 hash_del(&req->hash_node);
4913 io_poll_complete(req, req->result, 0);
4914 spin_unlock_irq(&ctx->completion_lock);
4916 nxt = io_put_req_find_next(req);
4917 io_cqring_ev_posted(ctx);
4919 __io_req_task_submit(nxt);
4922 percpu_ref_put(&ctx->refs);
4925 static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode,
4926 int sync, void *key)
4928 struct io_kiocb *req = wait->private;
4929 struct io_poll_iocb *poll = io_poll_get_single(req);
4930 __poll_t mask = key_to_poll(key);
4932 /* for instances that support it check for an event match first: */
4933 if (mask && !(mask & poll->events))
4936 list_del_init(&wait->entry);
4938 if (poll && poll->head) {
4941 spin_lock(&poll->head->lock);
4942 done = list_empty(&poll->wait.entry);
4944 list_del_init(&poll->wait.entry);
4945 /* make sure double remove sees this as being gone */
4946 wait->private = NULL;
4947 spin_unlock(&poll->head->lock);
4949 /* use wait func handler, so it matches the rq type */
4950 poll->wait.func(&poll->wait, mode, sync, key);
4953 refcount_dec(&req->refs);
4957 static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
4958 wait_queue_func_t wake_func)
4962 poll->canceled = false;
4963 poll->events = events;
4964 INIT_LIST_HEAD(&poll->wait.entry);
4965 init_waitqueue_func_entry(&poll->wait, wake_func);
4968 static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
4969 struct wait_queue_head *head,
4970 struct io_poll_iocb **poll_ptr)
4972 struct io_kiocb *req = pt->req;
4975 * If poll->head is already set, it's because the file being polled
4976 * uses multiple waitqueues for poll handling (eg one for read, one
4977 * for write). Setup a separate io_poll_iocb if this happens.
4979 if (unlikely(poll->head)) {
4980 struct io_poll_iocb *poll_one = poll;
4982 /* already have a 2nd entry, fail a third attempt */
4984 pt->error = -EINVAL;
4987 /* double add on the same waitqueue head, ignore */
4988 if (poll->head == head)
4990 poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
4992 pt->error = -ENOMEM;
4995 io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
4996 refcount_inc(&req->refs);
4997 poll->wait.private = req;
5004 if (poll->events & EPOLLEXCLUSIVE)
5005 add_wait_queue_exclusive(head, &poll->wait);
5007 add_wait_queue(head, &poll->wait);
5010 static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
5011 struct poll_table_struct *p)
5013 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
5014 struct async_poll *apoll = pt->req->apoll;
5016 __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
5019 static void io_async_task_func(struct callback_head *cb)
5021 struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work);
5022 struct async_poll *apoll = req->apoll;
5023 struct io_ring_ctx *ctx = req->ctx;
5025 trace_io_uring_task_run(req->ctx, req->opcode, req->user_data);
5027 if (io_poll_rewait(req, &apoll->poll)) {
5028 spin_unlock_irq(&ctx->completion_lock);
5029 percpu_ref_put(&ctx->refs);
5033 /* If req is still hashed, it cannot have been canceled. Don't check. */
5034 if (hash_hashed(&req->hash_node))
5035 hash_del(&req->hash_node);
5037 io_poll_remove_double(req);
5038 spin_unlock_irq(&ctx->completion_lock);
5040 if (!READ_ONCE(apoll->poll.canceled))
5041 __io_req_task_submit(req);
5043 __io_req_task_cancel(req, -ECANCELED);
5045 percpu_ref_put(&ctx->refs);
5046 kfree(apoll->double_poll);
5050 static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5053 struct io_kiocb *req = wait->private;
5054 struct io_poll_iocb *poll = &req->apoll->poll;
5056 trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data,
5059 return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func);
5062 static void io_poll_req_insert(struct io_kiocb *req)
5064 struct io_ring_ctx *ctx = req->ctx;
5065 struct hlist_head *list;
5067 list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
5068 hlist_add_head(&req->hash_node, list);
5071 static __poll_t __io_arm_poll_handler(struct io_kiocb *req,
5072 struct io_poll_iocb *poll,
5073 struct io_poll_table *ipt, __poll_t mask,
5074 wait_queue_func_t wake_func)
5075 __acquires(&ctx->completion_lock)
5077 struct io_ring_ctx *ctx = req->ctx;
5078 bool cancel = false;
5080 INIT_HLIST_NODE(&req->hash_node);
5081 io_init_poll_iocb(poll, mask, wake_func);
5082 poll->file = req->file;
5083 poll->wait.private = req;
5085 ipt->pt._key = mask;
5087 ipt->error = -EINVAL;
5089 mask = vfs_poll(req->file, &ipt->pt) & poll->events;
5091 spin_lock_irq(&ctx->completion_lock);
5092 if (likely(poll->head)) {
5093 spin_lock(&poll->head->lock);
5094 if (unlikely(list_empty(&poll->wait.entry))) {
5100 if (mask || ipt->error)
5101 list_del_init(&poll->wait.entry);
5103 WRITE_ONCE(poll->canceled, true);
5104 else if (!poll->done) /* actually waiting for an event */
5105 io_poll_req_insert(req);
5106 spin_unlock(&poll->head->lock);
5112 static bool io_arm_poll_handler(struct io_kiocb *req)
5114 const struct io_op_def *def = &io_op_defs[req->opcode];
5115 struct io_ring_ctx *ctx = req->ctx;
5116 struct async_poll *apoll;
5117 struct io_poll_table ipt;
5121 if (!req->file || !file_can_poll(req->file))
5123 if (req->flags & REQ_F_POLLED)
5127 else if (def->pollout)
5131 /* if we can't nonblock try, then no point in arming a poll handler */
5132 if (!io_file_supports_async(req->file, rw))
5135 apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
5136 if (unlikely(!apoll))
5138 apoll->double_poll = NULL;
5140 req->flags |= REQ_F_POLLED;
5145 mask |= POLLIN | POLLRDNORM;
5147 mask |= POLLOUT | POLLWRNORM;
5149 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5150 if ((req->opcode == IORING_OP_RECVMSG) &&
5151 (req->sr_msg.msg_flags & MSG_ERRQUEUE))
5154 mask |= POLLERR | POLLPRI;
5156 ipt.pt._qproc = io_async_queue_proc;
5158 ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask,
5160 if (ret || ipt.error) {
5161 io_poll_remove_double(req);
5162 spin_unlock_irq(&ctx->completion_lock);
5163 kfree(apoll->double_poll);
5167 spin_unlock_irq(&ctx->completion_lock);
5168 trace_io_uring_poll_arm(ctx, req->opcode, req->user_data, mask,
5169 apoll->poll.events);
5173 static bool __io_poll_remove_one(struct io_kiocb *req,
5174 struct io_poll_iocb *poll)
5176 bool do_complete = false;
5178 spin_lock(&poll->head->lock);
5179 WRITE_ONCE(poll->canceled, true);
5180 if (!list_empty(&poll->wait.entry)) {
5181 list_del_init(&poll->wait.entry);
5184 spin_unlock(&poll->head->lock);
5185 hash_del(&req->hash_node);
5189 static bool io_poll_remove_one(struct io_kiocb *req)
5193 io_poll_remove_double(req);
5195 if (req->opcode == IORING_OP_POLL_ADD) {
5196 do_complete = __io_poll_remove_one(req, &req->poll);
5198 struct async_poll *apoll = req->apoll;
5200 /* non-poll requests have submit ref still */
5201 do_complete = __io_poll_remove_one(req, &apoll->poll);
5204 kfree(apoll->double_poll);
5210 io_cqring_fill_event(req, -ECANCELED);
5211 io_commit_cqring(req->ctx);
5212 req_set_fail_links(req);
5213 io_put_req_deferred(req, 1);
5220 * Returns true if we found and killed one or more poll requests
5222 static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
5223 struct files_struct *files)
5225 struct hlist_node *tmp;
5226 struct io_kiocb *req;
5229 spin_lock_irq(&ctx->completion_lock);
5230 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
5231 struct hlist_head *list;
5233 list = &ctx->cancel_hash[i];
5234 hlist_for_each_entry_safe(req, tmp, list, hash_node) {
5235 if (io_match_task(req, tsk, files))
5236 posted += io_poll_remove_one(req);
5239 spin_unlock_irq(&ctx->completion_lock);
5242 io_cqring_ev_posted(ctx);
5247 static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr)
5249 struct hlist_head *list;
5250 struct io_kiocb *req;
5252 list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
5253 hlist_for_each_entry(req, list, hash_node) {
5254 if (sqe_addr != req->user_data)
5256 if (io_poll_remove_one(req))
5264 static int io_poll_remove_prep(struct io_kiocb *req,
5265 const struct io_uring_sqe *sqe)
5267 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5269 if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
5273 req->poll_remove.addr = READ_ONCE(sqe->addr);
5278 * Find a running poll command that matches one specified in sqe->addr,
5279 * and remove it if found.
5281 static int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
5283 struct io_ring_ctx *ctx = req->ctx;
5286 spin_lock_irq(&ctx->completion_lock);
5287 ret = io_poll_cancel(ctx, req->poll_remove.addr);
5288 spin_unlock_irq(&ctx->completion_lock);
5291 req_set_fail_links(req);
5292 io_req_complete(req, ret);
5296 static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5299 struct io_kiocb *req = wait->private;
5300 struct io_poll_iocb *poll = &req->poll;
5302 return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func);
5305 static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
5306 struct poll_table_struct *p)
5308 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
5310 __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
5313 static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5315 struct io_poll_iocb *poll = &req->poll;
5318 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5320 if (sqe->addr || sqe->ioprio || sqe->off || sqe->len || sqe->buf_index)
5323 events = READ_ONCE(sqe->poll32_events);
5325 events = swahw32(events);
5327 poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP |
5328 (events & EPOLLEXCLUSIVE);
5332 static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
5334 struct io_poll_iocb *poll = &req->poll;
5335 struct io_ring_ctx *ctx = req->ctx;
5336 struct io_poll_table ipt;
5339 ipt.pt._qproc = io_poll_queue_proc;
5341 mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,
5344 if (mask) { /* no async, we'd stolen it */
5346 io_poll_complete(req, mask, 0);
5348 spin_unlock_irq(&ctx->completion_lock);
5351 io_cqring_ev_posted(ctx);
5357 static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
5359 struct io_timeout_data *data = container_of(timer,
5360 struct io_timeout_data, timer);
5361 struct io_kiocb *req = data->req;
5362 struct io_ring_ctx *ctx = req->ctx;
5363 unsigned long flags;
5365 spin_lock_irqsave(&ctx->completion_lock, flags);
5366 list_del_init(&req->timeout.list);
5367 atomic_set(&req->ctx->cq_timeouts,
5368 atomic_read(&req->ctx->cq_timeouts) + 1);
5370 io_cqring_fill_event(req, -ETIME);
5371 io_commit_cqring(ctx);
5372 spin_unlock_irqrestore(&ctx->completion_lock, flags);
5374 io_cqring_ev_posted(ctx);
5375 req_set_fail_links(req);
5377 return HRTIMER_NORESTART;
5380 static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
5383 struct io_timeout_data *io;
5384 struct io_kiocb *req;
5387 list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
5388 if (user_data == req->user_data) {
5395 return ERR_PTR(ret);
5397 io = req->async_data;
5398 ret = hrtimer_try_to_cancel(&io->timer);
5400 return ERR_PTR(-EALREADY);
5401 list_del_init(&req->timeout.list);
5405 static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
5407 struct io_kiocb *req = io_timeout_extract(ctx, user_data);
5410 return PTR_ERR(req);
5412 req_set_fail_links(req);
5413 io_cqring_fill_event(req, -ECANCELED);
5414 io_put_req_deferred(req, 1);
5418 static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
5419 struct timespec64 *ts, enum hrtimer_mode mode)
5421 struct io_kiocb *req = io_timeout_extract(ctx, user_data);
5422 struct io_timeout_data *data;
5425 return PTR_ERR(req);
5427 req->timeout.off = 0; /* noseq */
5428 data = req->async_data;
5429 list_add_tail(&req->timeout.list, &ctx->timeout_list);
5430 hrtimer_init(&data->timer, CLOCK_MONOTONIC, mode);
5431 data->timer.function = io_timeout_fn;
5432 hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
5436 static int io_timeout_remove_prep(struct io_kiocb *req,
5437 const struct io_uring_sqe *sqe)
5439 struct io_timeout_rem *tr = &req->timeout_rem;
5441 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5443 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5445 if (sqe->ioprio || sqe->buf_index || sqe->len)
5448 tr->addr = READ_ONCE(sqe->addr);
5449 tr->flags = READ_ONCE(sqe->timeout_flags);
5450 if (tr->flags & IORING_TIMEOUT_UPDATE) {
5451 if (tr->flags & ~(IORING_TIMEOUT_UPDATE|IORING_TIMEOUT_ABS))
5453 if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
5455 } else if (tr->flags) {
5456 /* timeout removal doesn't support flags */
5463 static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
5465 return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
5470 * Remove or update an existing timeout command
5472 static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
5474 struct io_timeout_rem *tr = &req->timeout_rem;
5475 struct io_ring_ctx *ctx = req->ctx;
5478 spin_lock_irq(&ctx->completion_lock);
5479 if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE))
5480 ret = io_timeout_cancel(ctx, tr->addr);
5482 ret = io_timeout_update(ctx, tr->addr, &tr->ts,
5483 io_translate_timeout_mode(tr->flags));
5485 io_cqring_fill_event(req, ret);
5486 io_commit_cqring(ctx);
5487 spin_unlock_irq(&ctx->completion_lock);
5488 io_cqring_ev_posted(ctx);
5490 req_set_fail_links(req);
5495 static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
5496 bool is_timeout_link)
5498 struct io_timeout_data *data;
5500 u32 off = READ_ONCE(sqe->off);
5502 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5504 if (sqe->ioprio || sqe->buf_index || sqe->len != 1)
5506 if (off && is_timeout_link)
5508 flags = READ_ONCE(sqe->timeout_flags);
5509 if (flags & ~IORING_TIMEOUT_ABS)
5512 req->timeout.off = off;
5514 if (!req->async_data && io_alloc_async_data(req))
5517 data = req->async_data;
5520 if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
5523 data->mode = io_translate_timeout_mode(flags);
5524 hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode);
5525 io_req_track_inflight(req);
5529 static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
5531 struct io_ring_ctx *ctx = req->ctx;
5532 struct io_timeout_data *data = req->async_data;
5533 struct list_head *entry;
5534 u32 tail, off = req->timeout.off;
5536 spin_lock_irq(&ctx->completion_lock);
5539 * sqe->off holds how many events that need to occur for this
5540 * timeout event to be satisfied. If it isn't set, then this is
5541 * a pure timeout request, sequence isn't used.
5543 if (io_is_timeout_noseq(req)) {
5544 entry = ctx->timeout_list.prev;
5548 tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
5549 req->timeout.target_seq = tail + off;
5551 /* Update the last seq here in case io_flush_timeouts() hasn't.
5552 * This is safe because ->completion_lock is held, and submissions
5553 * and completions are never mixed in the same ->completion_lock section.
5555 ctx->cq_last_tm_flush = tail;
5558 * Insertion sort, ensuring the first entry in the list is always
5559 * the one we need first.
5561 list_for_each_prev(entry, &ctx->timeout_list) {
5562 struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
5565 if (io_is_timeout_noseq(nxt))
5567 /* nxt.seq is behind @tail, otherwise would've been completed */
5568 if (off >= nxt->timeout.target_seq - tail)
5572 list_add(&req->timeout.list, entry);
5573 data->timer.function = io_timeout_fn;
5574 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
5575 spin_unlock_irq(&ctx->completion_lock);
5579 struct io_cancel_data {
5580 struct io_ring_ctx *ctx;
5584 static bool io_cancel_cb(struct io_wq_work *work, void *data)
5586 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
5587 struct io_cancel_data *cd = data;
5589 return req->ctx == cd->ctx && req->user_data == cd->user_data;
5592 static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
5593 struct io_ring_ctx *ctx)
5595 struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, };
5596 enum io_wq_cancel cancel_ret;
5599 if (!tctx || !tctx->io_wq)
5602 cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false);
5603 switch (cancel_ret) {
5604 case IO_WQ_CANCEL_OK:
5607 case IO_WQ_CANCEL_RUNNING:
5610 case IO_WQ_CANCEL_NOTFOUND:
5618 static void io_async_find_and_cancel(struct io_ring_ctx *ctx,
5619 struct io_kiocb *req, __u64 sqe_addr,
5622 unsigned long flags;
5625 ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
5626 if (ret != -ENOENT) {
5627 spin_lock_irqsave(&ctx->completion_lock, flags);
5631 spin_lock_irqsave(&ctx->completion_lock, flags);
5632 ret = io_timeout_cancel(ctx, sqe_addr);
5635 ret = io_poll_cancel(ctx, sqe_addr);
5639 io_cqring_fill_event(req, ret);
5640 io_commit_cqring(ctx);
5641 spin_unlock_irqrestore(&ctx->completion_lock, flags);
5642 io_cqring_ev_posted(ctx);
5645 req_set_fail_links(req);
5649 static int io_async_cancel_prep(struct io_kiocb *req,
5650 const struct io_uring_sqe *sqe)
5652 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5654 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5656 if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags)
5659 req->cancel.addr = READ_ONCE(sqe->addr);
5663 static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
5665 struct io_ring_ctx *ctx = req->ctx;
5667 io_async_find_and_cancel(ctx, req, req->cancel.addr, 0);
5671 static int io_rsrc_update_prep(struct io_kiocb *req,
5672 const struct io_uring_sqe *sqe)
5674 if (unlikely(req->ctx->flags & IORING_SETUP_SQPOLL))
5676 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5678 if (sqe->ioprio || sqe->rw_flags)
5681 req->rsrc_update.offset = READ_ONCE(sqe->off);
5682 req->rsrc_update.nr_args = READ_ONCE(sqe->len);
5683 if (!req->rsrc_update.nr_args)
5685 req->rsrc_update.arg = READ_ONCE(sqe->addr);
5689 static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
5691 struct io_ring_ctx *ctx = req->ctx;
5692 struct io_uring_rsrc_update up;
5695 if (issue_flags & IO_URING_F_NONBLOCK)
5698 up.offset = req->rsrc_update.offset;
5699 up.data = req->rsrc_update.arg;
5701 mutex_lock(&ctx->uring_lock);
5702 ret = __io_sqe_files_update(ctx, &up, req->rsrc_update.nr_args);
5703 mutex_unlock(&ctx->uring_lock);
5706 req_set_fail_links(req);
5707 __io_req_complete(req, issue_flags, ret, 0);
5711 static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5713 switch (req->opcode) {
5716 case IORING_OP_READV:
5717 case IORING_OP_READ_FIXED:
5718 case IORING_OP_READ:
5719 return io_read_prep(req, sqe);
5720 case IORING_OP_WRITEV:
5721 case IORING_OP_WRITE_FIXED:
5722 case IORING_OP_WRITE:
5723 return io_write_prep(req, sqe);
5724 case IORING_OP_POLL_ADD:
5725 return io_poll_add_prep(req, sqe);
5726 case IORING_OP_POLL_REMOVE:
5727 return io_poll_remove_prep(req, sqe);
5728 case IORING_OP_FSYNC:
5729 return io_fsync_prep(req, sqe);
5730 case IORING_OP_SYNC_FILE_RANGE:
5731 return io_sfr_prep(req, sqe);
5732 case IORING_OP_SENDMSG:
5733 case IORING_OP_SEND:
5734 return io_sendmsg_prep(req, sqe);
5735 case IORING_OP_RECVMSG:
5736 case IORING_OP_RECV:
5737 return io_recvmsg_prep(req, sqe);
5738 case IORING_OP_CONNECT:
5739 return io_connect_prep(req, sqe);
5740 case IORING_OP_TIMEOUT:
5741 return io_timeout_prep(req, sqe, false);
5742 case IORING_OP_TIMEOUT_REMOVE:
5743 return io_timeout_remove_prep(req, sqe);
5744 case IORING_OP_ASYNC_CANCEL:
5745 return io_async_cancel_prep(req, sqe);
5746 case IORING_OP_LINK_TIMEOUT:
5747 return io_timeout_prep(req, sqe, true);
5748 case IORING_OP_ACCEPT:
5749 return io_accept_prep(req, sqe);
5750 case IORING_OP_FALLOCATE:
5751 return io_fallocate_prep(req, sqe);
5752 case IORING_OP_OPENAT:
5753 return io_openat_prep(req, sqe);
5754 case IORING_OP_CLOSE:
5755 return io_close_prep(req, sqe);
5756 case IORING_OP_FILES_UPDATE:
5757 return io_rsrc_update_prep(req, sqe);
5758 case IORING_OP_STATX:
5759 return io_statx_prep(req, sqe);
5760 case IORING_OP_FADVISE:
5761 return io_fadvise_prep(req, sqe);
5762 case IORING_OP_MADVISE:
5763 return io_madvise_prep(req, sqe);
5764 case IORING_OP_OPENAT2:
5765 return io_openat2_prep(req, sqe);
5766 case IORING_OP_EPOLL_CTL:
5767 return io_epoll_ctl_prep(req, sqe);
5768 case IORING_OP_SPLICE:
5769 return io_splice_prep(req, sqe);
5770 case IORING_OP_PROVIDE_BUFFERS:
5771 return io_provide_buffers_prep(req, sqe);
5772 case IORING_OP_REMOVE_BUFFERS:
5773 return io_remove_buffers_prep(req, sqe);
5775 return io_tee_prep(req, sqe);
5776 case IORING_OP_SHUTDOWN:
5777 return io_shutdown_prep(req, sqe);
5778 case IORING_OP_RENAMEAT:
5779 return io_renameat_prep(req, sqe);
5780 case IORING_OP_UNLINKAT:
5781 return io_unlinkat_prep(req, sqe);
5784 printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
5789 static int io_req_prep_async(struct io_kiocb *req)
5791 switch (req->opcode) {
5792 case IORING_OP_READV:
5793 case IORING_OP_READ_FIXED:
5794 case IORING_OP_READ:
5795 return io_rw_prep_async(req, READ);
5796 case IORING_OP_WRITEV:
5797 case IORING_OP_WRITE_FIXED:
5798 case IORING_OP_WRITE:
5799 return io_rw_prep_async(req, WRITE);
5800 case IORING_OP_SENDMSG:
5801 case IORING_OP_SEND:
5802 return io_sendmsg_prep_async(req);
5803 case IORING_OP_RECVMSG:
5804 case IORING_OP_RECV:
5805 return io_recvmsg_prep_async(req);
5806 case IORING_OP_CONNECT:
5807 return io_connect_prep_async(req);
5812 static int io_req_defer_prep(struct io_kiocb *req)
5814 if (!io_op_defs[req->opcode].needs_async_data)
5816 /* some opcodes init it during the inital prep */
5817 if (req->async_data)
5819 if (__io_alloc_async_data(req))
5821 return io_req_prep_async(req);
5824 static u32 io_get_sequence(struct io_kiocb *req)
5826 struct io_kiocb *pos;
5827 struct io_ring_ctx *ctx = req->ctx;
5828 u32 total_submitted, nr_reqs = 0;
5830 io_for_each_link(pos, req)
5833 total_submitted = ctx->cached_sq_head - ctx->cached_sq_dropped;
5834 return total_submitted - nr_reqs;
5837 static int io_req_defer(struct io_kiocb *req)
5839 struct io_ring_ctx *ctx = req->ctx;
5840 struct io_defer_entry *de;
5844 /* Still need defer if there is pending req in defer list. */
5845 if (likely(list_empty_careful(&ctx->defer_list) &&
5846 !(req->flags & REQ_F_IO_DRAIN)))
5849 seq = io_get_sequence(req);
5850 /* Still a chance to pass the sequence check */
5851 if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
5854 ret = io_req_defer_prep(req);
5857 io_prep_async_link(req);
5858 de = kmalloc(sizeof(*de), GFP_KERNEL);
5862 spin_lock_irq(&ctx->completion_lock);
5863 if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
5864 spin_unlock_irq(&ctx->completion_lock);
5866 io_queue_async_work(req);
5867 return -EIOCBQUEUED;
5870 trace_io_uring_defer(ctx, req, req->user_data);
5873 list_add_tail(&de->list, &ctx->defer_list);
5874 spin_unlock_irq(&ctx->completion_lock);
5875 return -EIOCBQUEUED;
5878 static void __io_clean_op(struct io_kiocb *req)
5880 if (req->flags & REQ_F_BUFFER_SELECTED) {
5881 switch (req->opcode) {
5882 case IORING_OP_READV:
5883 case IORING_OP_READ_FIXED:
5884 case IORING_OP_READ:
5885 kfree((void *)(unsigned long)req->rw.addr);
5887 case IORING_OP_RECVMSG:
5888 case IORING_OP_RECV:
5889 kfree(req->sr_msg.kbuf);
5892 req->flags &= ~REQ_F_BUFFER_SELECTED;
5895 if (req->flags & REQ_F_NEED_CLEANUP) {
5896 switch (req->opcode) {
5897 case IORING_OP_READV:
5898 case IORING_OP_READ_FIXED:
5899 case IORING_OP_READ:
5900 case IORING_OP_WRITEV:
5901 case IORING_OP_WRITE_FIXED:
5902 case IORING_OP_WRITE: {
5903 struct io_async_rw *io = req->async_data;
5905 kfree(io->free_iovec);
5908 case IORING_OP_RECVMSG:
5909 case IORING_OP_SENDMSG: {
5910 struct io_async_msghdr *io = req->async_data;
5912 kfree(io->free_iov);
5915 case IORING_OP_SPLICE:
5917 io_put_file(req, req->splice.file_in,
5918 (req->splice.flags & SPLICE_F_FD_IN_FIXED));
5920 case IORING_OP_OPENAT:
5921 case IORING_OP_OPENAT2:
5922 if (req->open.filename)
5923 putname(req->open.filename);
5925 case IORING_OP_RENAMEAT:
5926 putname(req->rename.oldpath);
5927 putname(req->rename.newpath);
5929 case IORING_OP_UNLINKAT:
5930 putname(req->unlink.filename);
5933 req->flags &= ~REQ_F_NEED_CLEANUP;
5937 static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
5939 struct io_ring_ctx *ctx = req->ctx;
5940 const struct cred *creds = NULL;
5943 if (req->work.creds && req->work.creds != current_cred())
5944 creds = override_creds(req->work.creds);
5946 switch (req->opcode) {
5948 ret = io_nop(req, issue_flags);
5950 case IORING_OP_READV:
5951 case IORING_OP_READ_FIXED:
5952 case IORING_OP_READ:
5953 ret = io_read(req, issue_flags);
5955 case IORING_OP_WRITEV:
5956 case IORING_OP_WRITE_FIXED:
5957 case IORING_OP_WRITE:
5958 ret = io_write(req, issue_flags);
5960 case IORING_OP_FSYNC:
5961 ret = io_fsync(req, issue_flags);
5963 case IORING_OP_POLL_ADD:
5964 ret = io_poll_add(req, issue_flags);
5966 case IORING_OP_POLL_REMOVE:
5967 ret = io_poll_remove(req, issue_flags);
5969 case IORING_OP_SYNC_FILE_RANGE:
5970 ret = io_sync_file_range(req, issue_flags);
5972 case IORING_OP_SENDMSG:
5973 ret = io_sendmsg(req, issue_flags);
5975 case IORING_OP_SEND:
5976 ret = io_send(req, issue_flags);
5978 case IORING_OP_RECVMSG:
5979 ret = io_recvmsg(req, issue_flags);
5981 case IORING_OP_RECV:
5982 ret = io_recv(req, issue_flags);
5984 case IORING_OP_TIMEOUT:
5985 ret = io_timeout(req, issue_flags);
5987 case IORING_OP_TIMEOUT_REMOVE:
5988 ret = io_timeout_remove(req, issue_flags);
5990 case IORING_OP_ACCEPT:
5991 ret = io_accept(req, issue_flags);
5993 case IORING_OP_CONNECT:
5994 ret = io_connect(req, issue_flags);
5996 case IORING_OP_ASYNC_CANCEL:
5997 ret = io_async_cancel(req, issue_flags);
5999 case IORING_OP_FALLOCATE:
6000 ret = io_fallocate(req, issue_flags);
6002 case IORING_OP_OPENAT:
6003 ret = io_openat(req, issue_flags);
6005 case IORING_OP_CLOSE:
6006 ret = io_close(req, issue_flags);
6008 case IORING_OP_FILES_UPDATE:
6009 ret = io_files_update(req, issue_flags);
6011 case IORING_OP_STATX:
6012 ret = io_statx(req, issue_flags);
6014 case IORING_OP_FADVISE:
6015 ret = io_fadvise(req, issue_flags);
6017 case IORING_OP_MADVISE:
6018 ret = io_madvise(req, issue_flags);
6020 case IORING_OP_OPENAT2:
6021 ret = io_openat2(req, issue_flags);
6023 case IORING_OP_EPOLL_CTL:
6024 ret = io_epoll_ctl(req, issue_flags);
6026 case IORING_OP_SPLICE:
6027 ret = io_splice(req, issue_flags);
6029 case IORING_OP_PROVIDE_BUFFERS:
6030 ret = io_provide_buffers(req, issue_flags);
6032 case IORING_OP_REMOVE_BUFFERS:
6033 ret = io_remove_buffers(req, issue_flags);
6036 ret = io_tee(req, issue_flags);
6038 case IORING_OP_SHUTDOWN:
6039 ret = io_shutdown(req, issue_flags);
6041 case IORING_OP_RENAMEAT:
6042 ret = io_renameat(req, issue_flags);
6044 case IORING_OP_UNLINKAT:
6045 ret = io_unlinkat(req, issue_flags);
6053 revert_creds(creds);
6058 /* If the op doesn't have a file, we're not polling for it */
6059 if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file) {
6060 const bool in_async = io_wq_current_is_worker();
6062 /* workqueue context doesn't hold uring_lock, grab it now */
6064 mutex_lock(&ctx->uring_lock);
6066 io_iopoll_req_issued(req, in_async);
6069 mutex_unlock(&ctx->uring_lock);
6075 static void io_wq_submit_work(struct io_wq_work *work)
6077 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
6078 struct io_kiocb *timeout;
6081 timeout = io_prep_linked_timeout(req);
6083 io_queue_linked_timeout(timeout);
6085 if (work->flags & IO_WQ_WORK_CANCEL)
6090 ret = io_issue_sqe(req, 0);
6092 * We can get EAGAIN for polled IO even though we're
6093 * forcing a sync submission from here, since we can't
6094 * wait for request slots on the block side.
6102 /* avoid locking problems by failing it from a clean context */
6104 /* io-wq is going to take one down */
6105 refcount_inc(&req->refs);
6106 io_req_task_queue_fail(req, ret);
6110 static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
6113 struct fixed_rsrc_table *table;
6115 table = &ctx->file_data->table[index >> IORING_FILE_TABLE_SHIFT];
6116 return table->files[index & IORING_FILE_TABLE_MASK];
6119 static struct file *io_file_get(struct io_submit_state *state,
6120 struct io_kiocb *req, int fd, bool fixed)
6122 struct io_ring_ctx *ctx = req->ctx;
6126 if (unlikely((unsigned int)fd >= ctx->nr_user_files))
6128 fd = array_index_nospec(fd, ctx->nr_user_files);
6129 file = io_file_from_index(ctx, fd);
6130 io_set_resource_node(req);
6132 trace_io_uring_file_get(ctx, fd);
6133 file = __io_file_get(state, fd);
6136 if (file && unlikely(file->f_op == &io_uring_fops))
6137 io_req_track_inflight(req);
6141 static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
6143 struct io_timeout_data *data = container_of(timer,
6144 struct io_timeout_data, timer);
6145 struct io_kiocb *prev, *req = data->req;
6146 struct io_ring_ctx *ctx = req->ctx;
6147 unsigned long flags;
6149 spin_lock_irqsave(&ctx->completion_lock, flags);
6150 prev = req->timeout.head;
6151 req->timeout.head = NULL;
6154 * We don't expect the list to be empty, that will only happen if we
6155 * race with the completion of the linked work.
6157 if (prev && refcount_inc_not_zero(&prev->refs))
6158 io_remove_next_linked(prev);
6161 spin_unlock_irqrestore(&ctx->completion_lock, flags);
6164 req_set_fail_links(prev);
6165 io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME);
6166 io_put_req_deferred(prev, 1);
6168 io_req_complete_post(req, -ETIME, 0);
6169 io_put_req_deferred(req, 1);
6171 return HRTIMER_NORESTART;
6174 static void __io_queue_linked_timeout(struct io_kiocb *req)
6177 * If the back reference is NULL, then our linked request finished
6178 * before we got a chance to setup the timer
6180 if (req->timeout.head) {
6181 struct io_timeout_data *data = req->async_data;
6183 data->timer.function = io_link_timeout_fn;
6184 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
6189 static void io_queue_linked_timeout(struct io_kiocb *req)
6191 struct io_ring_ctx *ctx = req->ctx;
6193 spin_lock_irq(&ctx->completion_lock);
6194 __io_queue_linked_timeout(req);
6195 spin_unlock_irq(&ctx->completion_lock);
6197 /* drop submission reference */
6201 static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
6203 struct io_kiocb *nxt = req->link;
6205 if (!nxt || (req->flags & REQ_F_LINK_TIMEOUT) ||
6206 nxt->opcode != IORING_OP_LINK_TIMEOUT)
6209 nxt->timeout.head = req;
6210 nxt->flags |= REQ_F_LTIMEOUT_ACTIVE;
6211 req->flags |= REQ_F_LINK_TIMEOUT;
6215 static void __io_queue_sqe(struct io_kiocb *req)
6217 struct io_kiocb *linked_timeout = io_prep_linked_timeout(req);
6220 ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
6223 * We async punt it if the file wasn't marked NOWAIT, or if the file
6224 * doesn't support non-blocking read/write attempts
6226 if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
6227 if (!io_arm_poll_handler(req)) {
6229 * Queued up for async execution, worker will release
6230 * submit reference when the iocb is actually submitted.
6232 io_queue_async_work(req);
6234 } else if (likely(!ret)) {
6235 /* drop submission reference */
6236 if (req->flags & REQ_F_COMPLETE_INLINE) {
6237 struct io_ring_ctx *ctx = req->ctx;
6238 struct io_comp_state *cs = &ctx->submit_state.comp;
6240 cs->reqs[cs->nr++] = req;
6241 if (cs->nr == ARRAY_SIZE(cs->reqs))
6242 io_submit_flush_completions(cs, ctx);
6247 req_set_fail_links(req);
6249 io_req_complete(req, ret);
6252 io_queue_linked_timeout(linked_timeout);
6255 static void io_queue_sqe(struct io_kiocb *req)
6259 ret = io_req_defer(req);
6261 if (ret != -EIOCBQUEUED) {
6263 req_set_fail_links(req);
6265 io_req_complete(req, ret);
6267 } else if (req->flags & REQ_F_FORCE_ASYNC) {
6268 ret = io_req_defer_prep(req);
6271 io_queue_async_work(req);
6273 __io_queue_sqe(req);
6278 * Check SQE restrictions (opcode and flags).
6280 * Returns 'true' if SQE is allowed, 'false' otherwise.
6282 static inline bool io_check_restriction(struct io_ring_ctx *ctx,
6283 struct io_kiocb *req,
6284 unsigned int sqe_flags)
6286 if (!ctx->restricted)
6289 if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
6292 if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
6293 ctx->restrictions.sqe_flags_required)
6296 if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
6297 ctx->restrictions.sqe_flags_required))
6303 static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
6304 const struct io_uring_sqe *sqe)
6306 struct io_submit_state *state;
6307 unsigned int sqe_flags;
6308 int personality, ret = 0;
6310 req->opcode = READ_ONCE(sqe->opcode);
6311 /* same numerical values with corresponding REQ_F_*, safe to copy */
6312 req->flags = sqe_flags = READ_ONCE(sqe->flags);
6313 req->user_data = READ_ONCE(sqe->user_data);
6314 req->async_data = NULL;
6318 req->fixed_rsrc_refs = NULL;
6319 /* one is dropped after submission, the other at completion */
6320 refcount_set(&req->refs, 2);
6321 req->task = current;
6324 /* enforce forwards compatibility on users */
6325 if (unlikely(sqe_flags & ~SQE_VALID_FLAGS)) {
6330 if (unlikely(req->opcode >= IORING_OP_LAST))
6333 if (unlikely(!io_check_restriction(ctx, req, sqe_flags)))
6336 if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
6337 !io_op_defs[req->opcode].buffer_select)
6340 req->work.list.next = NULL;
6341 personality = READ_ONCE(sqe->personality);
6343 req->work.creds = xa_load(&ctx->personalities, personality);
6344 if (!req->work.creds)
6346 get_cred(req->work.creds);
6348 req->work.creds = NULL;
6350 req->work.flags = 0;
6351 state = &ctx->submit_state;
6354 * Plug now if we have more than 1 IO left after this, and the target
6355 * is potentially a read/write to block based storage.
6357 if (!state->plug_started && state->ios_left > 1 &&
6358 io_op_defs[req->opcode].plug) {
6359 blk_start_plug(&state->plug);
6360 state->plug_started = true;
6363 if (io_op_defs[req->opcode].needs_file) {
6364 bool fixed = req->flags & REQ_F_FIXED_FILE;
6366 req->file = io_file_get(state, req, READ_ONCE(sqe->fd), fixed);
6367 if (unlikely(!req->file))
6375 static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
6376 const struct io_uring_sqe *sqe)
6378 struct io_submit_link *link = &ctx->submit_state.link;
6381 ret = io_init_req(ctx, req, sqe);
6382 if (unlikely(ret)) {
6385 io_req_complete(req, ret);
6387 /* fail even hard links since we don't submit */
6388 link->head->flags |= REQ_F_FAIL_LINK;
6389 io_put_req(link->head);
6390 io_req_complete(link->head, -ECANCELED);
6395 ret = io_req_prep(req, sqe);
6399 /* don't need @sqe from now on */
6400 trace_io_uring_submit_sqe(ctx, req->opcode, req->user_data,
6401 true, ctx->flags & IORING_SETUP_SQPOLL);
6404 * If we already have a head request, queue this one for async
6405 * submittal once the head completes. If we don't have a head but
6406 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6407 * submitted sync once the chain is complete. If none of those
6408 * conditions are true (normal request), then just queue it.
6411 struct io_kiocb *head = link->head;
6414 * Taking sequential execution of a link, draining both sides
6415 * of the link also fullfils IOSQE_IO_DRAIN semantics for all
6416 * requests in the link. So, it drains the head and the
6417 * next after the link request. The last one is done via
6418 * drain_next flag to persist the effect across calls.
6420 if (req->flags & REQ_F_IO_DRAIN) {
6421 head->flags |= REQ_F_IO_DRAIN;
6422 ctx->drain_next = 1;
6424 ret = io_req_defer_prep(req);
6427 trace_io_uring_link(ctx, req, head);
6428 link->last->link = req;
6431 /* last request of a link, enqueue the link */
6432 if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
6437 if (unlikely(ctx->drain_next)) {
6438 req->flags |= REQ_F_IO_DRAIN;
6439 ctx->drain_next = 0;
6441 if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
6453 * Batched submission is done, ensure local IO is flushed out.
6455 static void io_submit_state_end(struct io_submit_state *state,
6456 struct io_ring_ctx *ctx)
6458 if (state->link.head)
6459 io_queue_sqe(state->link.head);
6461 io_submit_flush_completions(&state->comp, ctx);
6462 if (state->plug_started)
6463 blk_finish_plug(&state->plug);
6464 io_state_file_put(state);
6468 * Start submission side cache.
6470 static void io_submit_state_start(struct io_submit_state *state,
6471 unsigned int max_ios)
6473 state->plug_started = false;
6474 state->ios_left = max_ios;
6475 /* set only head, no need to init link_last in advance */
6476 state->link.head = NULL;
6479 static void io_commit_sqring(struct io_ring_ctx *ctx)
6481 struct io_rings *rings = ctx->rings;
6484 * Ensure any loads from the SQEs are done at this point,
6485 * since once we write the new head, the application could
6486 * write new data to them.
6488 smp_store_release(&rings->sq.head, ctx->cached_sq_head);
6492 * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory
6493 * that is mapped by userspace. This means that care needs to be taken to
6494 * ensure that reads are stable, as we cannot rely on userspace always
6495 * being a good citizen. If members of the sqe are validated and then later
6496 * used, it's important that those reads are done through READ_ONCE() to
6497 * prevent a re-load down the line.
6499 static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
6501 u32 *sq_array = ctx->sq_array;
6505 * The cached sq head (or cq tail) serves two purposes:
6507 * 1) allows us to batch the cost of updating the user visible
6509 * 2) allows the kernel side to track the head on its own, even
6510 * though the application is the one updating it.
6512 head = READ_ONCE(sq_array[ctx->cached_sq_head++ & ctx->sq_mask]);
6513 if (likely(head < ctx->sq_entries))
6514 return &ctx->sq_sqes[head];
6516 /* drop invalid entries */
6517 ctx->cached_sq_dropped++;
6518 WRITE_ONCE(ctx->rings->sq_dropped, ctx->cached_sq_dropped);
6522 static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
6526 /* if we have a backlog and couldn't flush it all, return BUSY */
6527 if (test_bit(0, &ctx->sq_check_overflow)) {
6528 if (!__io_cqring_overflow_flush(ctx, false, NULL, NULL))
6532 /* make sure SQ entry isn't read before tail */
6533 nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
6535 if (!percpu_ref_tryget_many(&ctx->refs, nr))
6538 percpu_counter_add(¤t->io_uring->inflight, nr);
6539 refcount_add(nr, ¤t->usage);
6540 io_submit_state_start(&ctx->submit_state, nr);
6542 while (submitted < nr) {
6543 const struct io_uring_sqe *sqe;
6544 struct io_kiocb *req;
6546 req = io_alloc_req(ctx);
6547 if (unlikely(!req)) {
6549 submitted = -EAGAIN;
6552 sqe = io_get_sqe(ctx);
6553 if (unlikely(!sqe)) {
6554 kmem_cache_free(req_cachep, req);
6557 /* will complete beyond this point, count as submitted */
6559 if (io_submit_sqe(ctx, req, sqe))
6563 if (unlikely(submitted != nr)) {
6564 int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
6565 struct io_uring_task *tctx = current->io_uring;
6566 int unused = nr - ref_used;
6568 percpu_ref_put_many(&ctx->refs, unused);
6569 percpu_counter_sub(&tctx->inflight, unused);
6570 put_task_struct_many(current, unused);
6573 io_submit_state_end(&ctx->submit_state, ctx);
6574 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6575 io_commit_sqring(ctx);
6580 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
6582 /* Tell userspace we may need a wakeup call */
6583 spin_lock_irq(&ctx->completion_lock);
6584 ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP;
6585 spin_unlock_irq(&ctx->completion_lock);
6588 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
6590 spin_lock_irq(&ctx->completion_lock);
6591 ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP;
6592 spin_unlock_irq(&ctx->completion_lock);
6595 static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
6597 unsigned int to_submit;
6600 to_submit = io_sqring_entries(ctx);
6601 /* if we're handling multiple rings, cap submit size for fairness */
6602 if (cap_entries && to_submit > 8)
6605 if (!list_empty(&ctx->iopoll_list) || to_submit) {
6606 unsigned nr_events = 0;
6608 mutex_lock(&ctx->uring_lock);
6609 if (!list_empty(&ctx->iopoll_list))
6610 io_do_iopoll(ctx, &nr_events, 0);
6612 if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
6613 !(ctx->flags & IORING_SETUP_R_DISABLED))
6614 ret = io_submit_sqes(ctx, to_submit);
6615 mutex_unlock(&ctx->uring_lock);
6618 if (!io_sqring_full(ctx) && wq_has_sleeper(&ctx->sqo_sq_wait))
6619 wake_up(&ctx->sqo_sq_wait);
6624 static void io_sqd_update_thread_idle(struct io_sq_data *sqd)
6626 struct io_ring_ctx *ctx;
6627 unsigned sq_thread_idle = 0;
6629 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
6630 if (sq_thread_idle < ctx->sq_thread_idle)
6631 sq_thread_idle = ctx->sq_thread_idle;
6634 sqd->sq_thread_idle = sq_thread_idle;
6637 static void io_sqd_init_new(struct io_sq_data *sqd)
6639 struct io_ring_ctx *ctx;
6641 while (!list_empty(&sqd->ctx_new_list)) {
6642 ctx = list_first_entry(&sqd->ctx_new_list, struct io_ring_ctx, sqd_list);
6643 list_move_tail(&ctx->sqd_list, &sqd->ctx_list);
6644 complete(&ctx->sq_thread_comp);
6647 io_sqd_update_thread_idle(sqd);
6650 static int io_sq_thread(void *data)
6652 struct io_sq_data *sqd = data;
6653 struct io_ring_ctx *ctx;
6654 unsigned long timeout = 0;
6655 char buf[TASK_COMM_LEN];
6658 sprintf(buf, "iou-sqp-%d", sqd->task_pid);
6659 set_task_comm(current, buf);
6660 current->pf_io_worker = NULL;
6662 if (sqd->sq_cpu != -1)
6663 set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
6665 set_cpus_allowed_ptr(current, cpu_online_mask);
6666 current->flags |= PF_NO_SETAFFINITY;
6668 wait_for_completion(&sqd->startup);
6670 down_read(&sqd->rw_lock);
6672 while (!test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state)) {
6674 bool cap_entries, sqt_spin, needs_sched;
6676 if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state)) {
6677 up_read(&sqd->rw_lock);
6679 down_read(&sqd->rw_lock);
6682 if (unlikely(!list_empty(&sqd->ctx_new_list))) {
6683 io_sqd_init_new(sqd);
6684 timeout = jiffies + sqd->sq_thread_idle;
6686 if (fatal_signal_pending(current))
6689 cap_entries = !list_is_singular(&sqd->ctx_list);
6690 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
6691 const struct cred *creds = NULL;
6693 if (ctx->sq_creds != current_cred())
6694 creds = override_creds(ctx->sq_creds);
6695 ret = __io_sq_thread(ctx, cap_entries);
6697 revert_creds(creds);
6698 if (!sqt_spin && (ret > 0 || !list_empty(&ctx->iopoll_list)))
6702 if (sqt_spin || !time_after(jiffies, timeout)) {
6706 timeout = jiffies + sqd->sq_thread_idle;
6711 prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
6712 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
6713 if ((ctx->flags & IORING_SETUP_IOPOLL) &&
6714 !list_empty_careful(&ctx->iopoll_list)) {
6715 needs_sched = false;
6718 if (io_sqring_entries(ctx)) {
6719 needs_sched = false;
6724 if (needs_sched && !test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state)) {
6725 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6726 io_ring_set_wakeup_flag(ctx);
6728 up_read(&sqd->rw_lock);
6731 down_read(&sqd->rw_lock);
6732 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6733 io_ring_clear_wakeup_flag(ctx);
6736 finish_wait(&sqd->wait, &wait);
6737 timeout = jiffies + sqd->sq_thread_idle;
6740 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6741 io_uring_cancel_sqpoll(ctx);
6742 up_read(&sqd->rw_lock);
6746 down_write(&sqd->rw_lock);
6748 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6749 io_ring_set_wakeup_flag(ctx);
6750 up_write(&sqd->rw_lock);
6751 complete(&sqd->exited);
6755 struct io_wait_queue {
6756 struct wait_queue_entry wq;
6757 struct io_ring_ctx *ctx;
6759 unsigned nr_timeouts;
6762 static inline bool io_should_wake(struct io_wait_queue *iowq)
6764 struct io_ring_ctx *ctx = iowq->ctx;
6767 * Wake up if we have enough events, or if a timeout occurred since we
6768 * started waiting. For timeouts, we always want to return to userspace,
6769 * regardless of event count.
6771 return io_cqring_events(ctx) >= iowq->to_wait ||
6772 atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
6775 static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
6776 int wake_flags, void *key)
6778 struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
6782 * Cannot safely flush overflowed CQEs from here, ensure we wake up
6783 * the task, and the next invocation will do it.
6785 if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->cq_check_overflow))
6786 return autoremove_wake_function(curr, mode, wake_flags, key);
6790 static int io_run_task_work_sig(void)
6792 if (io_run_task_work())
6794 if (!signal_pending(current))
6796 if (test_tsk_thread_flag(current, TIF_NOTIFY_SIGNAL))
6797 return -ERESTARTSYS;
6801 /* when returns >0, the caller should retry */
6802 static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
6803 struct io_wait_queue *iowq,
6804 signed long *timeout)
6808 /* make sure we run task_work before checking for signals */
6809 ret = io_run_task_work_sig();
6810 if (ret || io_should_wake(iowq))
6812 /* let the caller flush overflows, retry */
6813 if (test_bit(0, &ctx->cq_check_overflow))
6816 *timeout = schedule_timeout(*timeout);
6817 return !*timeout ? -ETIME : 1;
6821 * Wait until events become available, if we don't already have some. The
6822 * application must reap them itself, as they reside on the shared cq ring.
6824 static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
6825 const sigset_t __user *sig, size_t sigsz,
6826 struct __kernel_timespec __user *uts)
6828 struct io_wait_queue iowq = {
6831 .func = io_wake_function,
6832 .entry = LIST_HEAD_INIT(iowq.wq.entry),
6835 .to_wait = min_events,
6837 struct io_rings *rings = ctx->rings;
6838 signed long timeout = MAX_SCHEDULE_TIMEOUT;
6842 io_cqring_overflow_flush(ctx, false, NULL, NULL);
6843 if (io_cqring_events(ctx) >= min_events)
6845 if (!io_run_task_work())
6850 #ifdef CONFIG_COMPAT
6851 if (in_compat_syscall())
6852 ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
6856 ret = set_user_sigmask(sig, sigsz);
6863 struct timespec64 ts;
6865 if (get_timespec64(&ts, uts))
6867 timeout = timespec64_to_jiffies(&ts);
6870 iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
6871 trace_io_uring_cqring_wait(ctx, min_events);
6873 /* if we can't even flush overflow, don't wait for more */
6874 if (!io_cqring_overflow_flush(ctx, false, NULL, NULL)) {
6878 prepare_to_wait_exclusive(&ctx->wait, &iowq.wq,
6879 TASK_INTERRUPTIBLE);
6880 ret = io_cqring_wait_schedule(ctx, &iowq, &timeout);
6881 finish_wait(&ctx->wait, &iowq.wq);
6885 restore_saved_sigmask_unless(ret == -EINTR);
6887 return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
6890 static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
6892 #if defined(CONFIG_UNIX)
6893 if (ctx->ring_sock) {
6894 struct sock *sock = ctx->ring_sock->sk;
6895 struct sk_buff *skb;
6897 while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
6903 for (i = 0; i < ctx->nr_user_files; i++) {
6906 file = io_file_from_index(ctx, i);
6913 static void io_rsrc_data_ref_zero(struct percpu_ref *ref)
6915 struct fixed_rsrc_data *data;
6917 data = container_of(ref, struct fixed_rsrc_data, refs);
6918 complete(&data->done);
6921 static inline void io_rsrc_ref_lock(struct io_ring_ctx *ctx)
6923 spin_lock_bh(&ctx->rsrc_ref_lock);
6926 static inline void io_rsrc_ref_unlock(struct io_ring_ctx *ctx)
6928 spin_unlock_bh(&ctx->rsrc_ref_lock);
6931 static void io_sqe_rsrc_set_node(struct io_ring_ctx *ctx,
6932 struct fixed_rsrc_data *rsrc_data,
6933 struct fixed_rsrc_ref_node *ref_node)
6935 io_rsrc_ref_lock(ctx);
6936 rsrc_data->node = ref_node;
6937 list_add_tail(&ref_node->node, &ctx->rsrc_ref_list);
6938 io_rsrc_ref_unlock(ctx);
6939 percpu_ref_get(&rsrc_data->refs);
6942 static void io_sqe_rsrc_kill_node(struct io_ring_ctx *ctx, struct fixed_rsrc_data *data)
6944 struct fixed_rsrc_ref_node *ref_node = NULL;
6946 io_rsrc_ref_lock(ctx);
6947 ref_node = data->node;
6949 io_rsrc_ref_unlock(ctx);
6951 percpu_ref_kill(&ref_node->refs);
6954 static int io_rsrc_ref_quiesce(struct fixed_rsrc_data *data,
6955 struct io_ring_ctx *ctx,
6956 void (*rsrc_put)(struct io_ring_ctx *ctx,
6957 struct io_rsrc_put *prsrc))
6959 struct fixed_rsrc_ref_node *backup_node;
6965 data->quiesce = true;
6968 backup_node = alloc_fixed_rsrc_ref_node(ctx);
6971 backup_node->rsrc_data = data;
6972 backup_node->rsrc_put = rsrc_put;
6974 io_sqe_rsrc_kill_node(ctx, data);
6975 percpu_ref_kill(&data->refs);
6976 flush_delayed_work(&ctx->rsrc_put_work);
6978 ret = wait_for_completion_interruptible(&data->done);
6982 percpu_ref_resurrect(&data->refs);
6983 io_sqe_rsrc_set_node(ctx, data, backup_node);
6985 reinit_completion(&data->done);
6986 mutex_unlock(&ctx->uring_lock);
6987 ret = io_run_task_work_sig();
6988 mutex_lock(&ctx->uring_lock);
6990 data->quiesce = false;
6993 destroy_fixed_rsrc_ref_node(backup_node);
6997 static struct fixed_rsrc_data *alloc_fixed_rsrc_data(struct io_ring_ctx *ctx)
6999 struct fixed_rsrc_data *data;
7001 data = kzalloc(sizeof(*data), GFP_KERNEL);
7005 if (percpu_ref_init(&data->refs, io_rsrc_data_ref_zero,
7006 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) {
7011 init_completion(&data->done);
7015 static void free_fixed_rsrc_data(struct fixed_rsrc_data *data)
7017 percpu_ref_exit(&data->refs);
7022 static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
7024 struct fixed_rsrc_data *data = ctx->file_data;
7025 unsigned nr_tables, i;
7029 * percpu_ref_is_dying() is to stop parallel files unregister
7030 * Since we possibly drop uring lock later in this function to
7033 if (!data || percpu_ref_is_dying(&data->refs))
7035 ret = io_rsrc_ref_quiesce(data, ctx, io_ring_file_put);
7039 __io_sqe_files_unregister(ctx);
7040 nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE);
7041 for (i = 0; i < nr_tables; i++)
7042 kfree(data->table[i].files);
7043 free_fixed_rsrc_data(data);
7044 ctx->file_data = NULL;
7045 ctx->nr_user_files = 0;
7049 static void io_sq_thread_unpark(struct io_sq_data *sqd)
7050 __releases(&sqd->rw_lock)
7052 if (sqd->thread == current)
7054 clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7055 up_write(&sqd->rw_lock);
7058 static void io_sq_thread_park(struct io_sq_data *sqd)
7059 __acquires(&sqd->rw_lock)
7061 if (sqd->thread == current)
7063 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7064 down_write(&sqd->rw_lock);
7065 /* set again for consistency, in case concurrent parks are happening */
7066 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7068 wake_up_process(sqd->thread);
7071 static void io_sq_thread_stop(struct io_sq_data *sqd)
7073 if (test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state))
7075 down_write(&sqd->rw_lock);
7077 up_write(&sqd->rw_lock);
7080 set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
7081 wake_up_process(sqd->thread);
7082 up_write(&sqd->rw_lock);
7083 wait_for_completion(&sqd->exited);
7086 static void io_put_sq_data(struct io_sq_data *sqd)
7088 if (refcount_dec_and_test(&sqd->refs)) {
7089 io_sq_thread_stop(sqd);
7094 static void io_sq_thread_finish(struct io_ring_ctx *ctx)
7096 struct io_sq_data *sqd = ctx->sq_data;
7099 complete(&sqd->startup);
7101 wait_for_completion(&ctx->sq_thread_comp);
7103 io_sq_thread_park(sqd);
7104 list_del(&ctx->sqd_list);
7105 io_sqd_update_thread_idle(sqd);
7106 io_sq_thread_unpark(sqd);
7108 io_put_sq_data(sqd);
7109 ctx->sq_data = NULL;
7111 put_cred(ctx->sq_creds);
7115 static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
7117 struct io_ring_ctx *ctx_attach;
7118 struct io_sq_data *sqd;
7121 f = fdget(p->wq_fd);
7123 return ERR_PTR(-ENXIO);
7124 if (f.file->f_op != &io_uring_fops) {
7126 return ERR_PTR(-EINVAL);
7129 ctx_attach = f.file->private_data;
7130 sqd = ctx_attach->sq_data;
7133 return ERR_PTR(-EINVAL);
7136 refcount_inc(&sqd->refs);
7141 static struct io_sq_data *io_get_sq_data(struct io_uring_params *p)
7143 struct io_sq_data *sqd;
7145 if (p->flags & IORING_SETUP_ATTACH_WQ)
7146 return io_attach_sq_data(p);
7148 sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
7150 return ERR_PTR(-ENOMEM);
7152 refcount_set(&sqd->refs, 1);
7153 INIT_LIST_HEAD(&sqd->ctx_list);
7154 INIT_LIST_HEAD(&sqd->ctx_new_list);
7155 init_rwsem(&sqd->rw_lock);
7156 init_waitqueue_head(&sqd->wait);
7157 init_completion(&sqd->startup);
7158 init_completion(&sqd->exited);
7162 #if defined(CONFIG_UNIX)
7164 * Ensure the UNIX gc is aware of our file set, so we are certain that
7165 * the io_uring can be safely unregistered on process exit, even if we have
7166 * loops in the file referencing.
7168 static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
7170 struct sock *sk = ctx->ring_sock->sk;
7171 struct scm_fp_list *fpl;
7172 struct sk_buff *skb;
7175 fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
7179 skb = alloc_skb(0, GFP_KERNEL);
7188 fpl->user = get_uid(current_user());
7189 for (i = 0; i < nr; i++) {
7190 struct file *file = io_file_from_index(ctx, i + offset);
7194 fpl->fp[nr_files] = get_file(file);
7195 unix_inflight(fpl->user, fpl->fp[nr_files]);
7200 fpl->max = SCM_MAX_FD;
7201 fpl->count = nr_files;
7202 UNIXCB(skb).fp = fpl;
7203 skb->destructor = unix_destruct_scm;
7204 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
7205 skb_queue_head(&sk->sk_receive_queue, skb);
7207 for (i = 0; i < nr_files; i++)
7218 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7219 * causes regular reference counting to break down. We rely on the UNIX
7220 * garbage collection to take care of this problem for us.
7222 static int io_sqe_files_scm(struct io_ring_ctx *ctx)
7224 unsigned left, total;
7228 left = ctx->nr_user_files;
7230 unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
7232 ret = __io_sqe_files_scm(ctx, this_files, total);
7236 total += this_files;
7242 while (total < ctx->nr_user_files) {
7243 struct file *file = io_file_from_index(ctx, total);
7253 static int io_sqe_files_scm(struct io_ring_ctx *ctx)
7259 static int io_sqe_alloc_file_tables(struct fixed_rsrc_data *file_data,
7260 unsigned nr_tables, unsigned nr_files)
7264 for (i = 0; i < nr_tables; i++) {
7265 struct fixed_rsrc_table *table = &file_data->table[i];
7266 unsigned this_files;
7268 this_files = min(nr_files, IORING_MAX_FILES_TABLE);
7269 table->files = kcalloc(this_files, sizeof(struct file *),
7273 nr_files -= this_files;
7279 for (i = 0; i < nr_tables; i++) {
7280 struct fixed_rsrc_table *table = &file_data->table[i];
7281 kfree(table->files);
7286 static void io_ring_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
7288 struct file *file = prsrc->file;
7289 #if defined(CONFIG_UNIX)
7290 struct sock *sock = ctx->ring_sock->sk;
7291 struct sk_buff_head list, *head = &sock->sk_receive_queue;
7292 struct sk_buff *skb;
7295 __skb_queue_head_init(&list);
7298 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7299 * remove this entry and rearrange the file array.
7301 skb = skb_dequeue(head);
7303 struct scm_fp_list *fp;
7305 fp = UNIXCB(skb).fp;
7306 for (i = 0; i < fp->count; i++) {
7309 if (fp->fp[i] != file)
7312 unix_notinflight(fp->user, fp->fp[i]);
7313 left = fp->count - 1 - i;
7315 memmove(&fp->fp[i], &fp->fp[i + 1],
7316 left * sizeof(struct file *));
7323 __skb_queue_tail(&list, skb);
7333 __skb_queue_tail(&list, skb);
7335 skb = skb_dequeue(head);
7338 if (skb_peek(&list)) {
7339 spin_lock_irq(&head->lock);
7340 while ((skb = __skb_dequeue(&list)) != NULL)
7341 __skb_queue_tail(head, skb);
7342 spin_unlock_irq(&head->lock);
7349 static void __io_rsrc_put_work(struct fixed_rsrc_ref_node *ref_node)
7351 struct fixed_rsrc_data *rsrc_data = ref_node->rsrc_data;
7352 struct io_ring_ctx *ctx = rsrc_data->ctx;
7353 struct io_rsrc_put *prsrc, *tmp;
7355 list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
7356 list_del(&prsrc->list);
7357 ref_node->rsrc_put(ctx, prsrc);
7361 percpu_ref_exit(&ref_node->refs);
7363 percpu_ref_put(&rsrc_data->refs);
7366 static void io_rsrc_put_work(struct work_struct *work)
7368 struct io_ring_ctx *ctx;
7369 struct llist_node *node;
7371 ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
7372 node = llist_del_all(&ctx->rsrc_put_llist);
7375 struct fixed_rsrc_ref_node *ref_node;
7376 struct llist_node *next = node->next;
7378 ref_node = llist_entry(node, struct fixed_rsrc_ref_node, llist);
7379 __io_rsrc_put_work(ref_node);
7384 static struct file **io_fixed_file_slot(struct fixed_rsrc_data *file_data,
7387 struct fixed_rsrc_table *table;
7389 table = &file_data->table[i >> IORING_FILE_TABLE_SHIFT];
7390 return &table->files[i & IORING_FILE_TABLE_MASK];
7393 static void io_rsrc_node_ref_zero(struct percpu_ref *ref)
7395 struct fixed_rsrc_ref_node *ref_node;
7396 struct fixed_rsrc_data *data;
7397 struct io_ring_ctx *ctx;
7398 bool first_add = false;
7401 ref_node = container_of(ref, struct fixed_rsrc_ref_node, refs);
7402 data = ref_node->rsrc_data;
7405 io_rsrc_ref_lock(ctx);
7406 ref_node->done = true;
7408 while (!list_empty(&ctx->rsrc_ref_list)) {
7409 ref_node = list_first_entry(&ctx->rsrc_ref_list,
7410 struct fixed_rsrc_ref_node, node);
7411 /* recycle ref nodes in order */
7412 if (!ref_node->done)
7414 list_del(&ref_node->node);
7415 first_add |= llist_add(&ref_node->llist, &ctx->rsrc_put_llist);
7417 io_rsrc_ref_unlock(ctx);
7419 if (percpu_ref_is_dying(&data->refs))
7423 mod_delayed_work(system_wq, &ctx->rsrc_put_work, 0);
7425 queue_delayed_work(system_wq, &ctx->rsrc_put_work, delay);
7428 static struct fixed_rsrc_ref_node *alloc_fixed_rsrc_ref_node(
7429 struct io_ring_ctx *ctx)
7431 struct fixed_rsrc_ref_node *ref_node;
7433 ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
7437 if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
7442 INIT_LIST_HEAD(&ref_node->node);
7443 INIT_LIST_HEAD(&ref_node->rsrc_list);
7444 ref_node->done = false;
7448 static void init_fixed_file_ref_node(struct io_ring_ctx *ctx,
7449 struct fixed_rsrc_ref_node *ref_node)
7451 ref_node->rsrc_data = ctx->file_data;
7452 ref_node->rsrc_put = io_ring_file_put;
7455 static void destroy_fixed_rsrc_ref_node(struct fixed_rsrc_ref_node *ref_node)
7457 percpu_ref_exit(&ref_node->refs);
7462 static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
7465 __s32 __user *fds = (__s32 __user *) arg;
7466 unsigned nr_tables, i;
7468 int fd, ret = -ENOMEM;
7469 struct fixed_rsrc_ref_node *ref_node;
7470 struct fixed_rsrc_data *file_data;
7476 if (nr_args > IORING_MAX_FIXED_FILES)
7479 file_data = alloc_fixed_rsrc_data(ctx);
7482 ctx->file_data = file_data;
7484 nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE);
7485 file_data->table = kcalloc(nr_tables, sizeof(*file_data->table),
7487 if (!file_data->table)
7490 if (io_sqe_alloc_file_tables(file_data, nr_tables, nr_args))
7493 for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
7494 if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
7498 /* allow sparse sets */
7508 * Don't allow io_uring instances to be registered. If UNIX
7509 * isn't enabled, then this causes a reference cycle and this
7510 * instance can never get freed. If UNIX is enabled we'll
7511 * handle it just fine, but there's still no point in allowing
7512 * a ring fd as it doesn't support regular read/write anyway.
7514 if (file->f_op == &io_uring_fops) {
7518 *io_fixed_file_slot(file_data, i) = file;
7521 ret = io_sqe_files_scm(ctx);
7523 io_sqe_files_unregister(ctx);
7527 ref_node = alloc_fixed_rsrc_ref_node(ctx);
7529 io_sqe_files_unregister(ctx);
7532 init_fixed_file_ref_node(ctx, ref_node);
7534 io_sqe_rsrc_set_node(ctx, file_data, ref_node);
7537 for (i = 0; i < ctx->nr_user_files; i++) {
7538 file = io_file_from_index(ctx, i);
7542 for (i = 0; i < nr_tables; i++)
7543 kfree(file_data->table[i].files);
7544 ctx->nr_user_files = 0;
7546 free_fixed_rsrc_data(ctx->file_data);
7547 ctx->file_data = NULL;
7551 static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
7554 #if defined(CONFIG_UNIX)
7555 struct sock *sock = ctx->ring_sock->sk;
7556 struct sk_buff_head *head = &sock->sk_receive_queue;
7557 struct sk_buff *skb;
7560 * See if we can merge this file into an existing skb SCM_RIGHTS
7561 * file set. If there's no room, fall back to allocating a new skb
7562 * and filling it in.
7564 spin_lock_irq(&head->lock);
7565 skb = skb_peek(head);
7567 struct scm_fp_list *fpl = UNIXCB(skb).fp;
7569 if (fpl->count < SCM_MAX_FD) {
7570 __skb_unlink(skb, head);
7571 spin_unlock_irq(&head->lock);
7572 fpl->fp[fpl->count] = get_file(file);
7573 unix_inflight(fpl->user, fpl->fp[fpl->count]);
7575 spin_lock_irq(&head->lock);
7576 __skb_queue_head(head, skb);
7581 spin_unlock_irq(&head->lock);
7588 return __io_sqe_files_scm(ctx, 1, index);
7594 static int io_queue_rsrc_removal(struct fixed_rsrc_data *data, void *rsrc)
7596 struct io_rsrc_put *prsrc;
7597 struct fixed_rsrc_ref_node *ref_node = data->node;
7599 prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
7604 list_add(&prsrc->list, &ref_node->rsrc_list);
7609 static inline int io_queue_file_removal(struct fixed_rsrc_data *data,
7612 return io_queue_rsrc_removal(data, (void *)file);
7615 static int __io_sqe_files_update(struct io_ring_ctx *ctx,
7616 struct io_uring_rsrc_update *up,
7619 struct fixed_rsrc_data *data = ctx->file_data;
7620 struct fixed_rsrc_ref_node *ref_node;
7621 struct file *file, **file_slot;
7625 bool needs_switch = false;
7627 if (check_add_overflow(up->offset, nr_args, &done))
7629 if (done > ctx->nr_user_files)
7632 ref_node = alloc_fixed_rsrc_ref_node(ctx);
7635 init_fixed_file_ref_node(ctx, ref_node);
7637 fds = u64_to_user_ptr(up->data);
7638 for (done = 0; done < nr_args; done++) {
7640 if (copy_from_user(&fd, &fds[done], sizeof(fd))) {
7644 if (fd == IORING_REGISTER_FILES_SKIP)
7647 i = array_index_nospec(up->offset + done, ctx->nr_user_files);
7648 file_slot = io_fixed_file_slot(ctx->file_data, i);
7651 err = io_queue_file_removal(data, *file_slot);
7655 needs_switch = true;
7664 * Don't allow io_uring instances to be registered. If
7665 * UNIX isn't enabled, then this causes a reference
7666 * cycle and this instance can never get freed. If UNIX
7667 * is enabled we'll handle it just fine, but there's
7668 * still no point in allowing a ring fd as it doesn't
7669 * support regular read/write anyway.
7671 if (file->f_op == &io_uring_fops) {
7677 err = io_sqe_file_register(ctx, file, i);
7687 percpu_ref_kill(&data->node->refs);
7688 io_sqe_rsrc_set_node(ctx, data, ref_node);
7690 destroy_fixed_rsrc_ref_node(ref_node);
7692 return done ? done : err;
7695 static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg,
7698 struct io_uring_rsrc_update up;
7700 if (!ctx->file_data)
7704 if (copy_from_user(&up, arg, sizeof(up)))
7709 return __io_sqe_files_update(ctx, &up, nr_args);
7712 static struct io_wq_work *io_free_work(struct io_wq_work *work)
7714 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
7716 req = io_put_req_find_next(req);
7717 return req ? &req->work : NULL;
7720 static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx)
7722 struct io_wq_hash *hash;
7723 struct io_wq_data data;
7724 unsigned int concurrency;
7726 hash = ctx->hash_map;
7728 hash = kzalloc(sizeof(*hash), GFP_KERNEL);
7730 return ERR_PTR(-ENOMEM);
7731 refcount_set(&hash->refs, 1);
7732 init_waitqueue_head(&hash->wait);
7733 ctx->hash_map = hash;
7737 data.free_work = io_free_work;
7738 data.do_work = io_wq_submit_work;
7740 /* Do QD, or 4 * CPUS, whatever is smallest */
7741 concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
7743 return io_wq_create(concurrency, &data);
7746 static int io_uring_alloc_task_context(struct task_struct *task,
7747 struct io_ring_ctx *ctx)
7749 struct io_uring_task *tctx;
7752 tctx = kmalloc(sizeof(*tctx), GFP_KERNEL);
7753 if (unlikely(!tctx))
7756 ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
7757 if (unlikely(ret)) {
7762 tctx->io_wq = io_init_wq_offload(ctx);
7763 if (IS_ERR(tctx->io_wq)) {
7764 ret = PTR_ERR(tctx->io_wq);
7765 percpu_counter_destroy(&tctx->inflight);
7771 init_waitqueue_head(&tctx->wait);
7773 atomic_set(&tctx->in_idle, 0);
7774 tctx->sqpoll = false;
7775 task->io_uring = tctx;
7776 spin_lock_init(&tctx->task_lock);
7777 INIT_WQ_LIST(&tctx->task_list);
7778 tctx->task_state = 0;
7779 init_task_work(&tctx->task_work, tctx_task_work);
7783 void __io_uring_free(struct task_struct *tsk)
7785 struct io_uring_task *tctx = tsk->io_uring;
7787 WARN_ON_ONCE(!xa_empty(&tctx->xa));
7788 WARN_ON_ONCE(tctx->io_wq);
7790 percpu_counter_destroy(&tctx->inflight);
7792 tsk->io_uring = NULL;
7795 static int io_sq_offload_create(struct io_ring_ctx *ctx,
7796 struct io_uring_params *p)
7800 /* Retain compatibility with failing for an invalid attach attempt */
7801 if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
7802 IORING_SETUP_ATTACH_WQ) {
7805 f = fdget(p->wq_fd);
7808 if (f.file->f_op != &io_uring_fops) {
7814 if (ctx->flags & IORING_SETUP_SQPOLL) {
7815 struct task_struct *tsk;
7816 struct io_sq_data *sqd;
7819 if (!capable(CAP_SYS_ADMIN) && !capable(CAP_SYS_NICE))
7822 sqd = io_get_sq_data(p);
7828 ctx->sq_creds = get_current_cred();
7830 io_sq_thread_park(sqd);
7831 list_add(&ctx->sqd_list, &sqd->ctx_new_list);
7832 io_sq_thread_unpark(sqd);
7834 ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
7835 if (!ctx->sq_thread_idle)
7836 ctx->sq_thread_idle = HZ;
7841 if (p->flags & IORING_SETUP_SQ_AFF) {
7842 int cpu = p->sq_thread_cpu;
7845 if (cpu >= nr_cpu_ids)
7847 if (!cpu_online(cpu))
7855 sqd->task_pid = current->pid;
7856 tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
7863 ret = io_uring_alloc_task_context(tsk, ctx);
7864 wake_up_new_task(tsk);
7867 complete(&sqd->startup);
7868 } else if (p->flags & IORING_SETUP_SQ_AFF) {
7869 /* Can't have SQ_AFF without SQPOLL */
7876 io_sq_thread_finish(ctx);
7880 static inline void __io_unaccount_mem(struct user_struct *user,
7881 unsigned long nr_pages)
7883 atomic_long_sub(nr_pages, &user->locked_vm);
7886 static inline int __io_account_mem(struct user_struct *user,
7887 unsigned long nr_pages)
7889 unsigned long page_limit, cur_pages, new_pages;
7891 /* Don't allow more pages than we can safely lock */
7892 page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
7895 cur_pages = atomic_long_read(&user->locked_vm);
7896 new_pages = cur_pages + nr_pages;
7897 if (new_pages > page_limit)
7899 } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
7900 new_pages) != cur_pages);
7905 static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
7908 __io_unaccount_mem(ctx->user, nr_pages);
7910 if (ctx->mm_account)
7911 atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
7914 static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
7919 ret = __io_account_mem(ctx->user, nr_pages);
7924 if (ctx->mm_account)
7925 atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
7930 static void io_mem_free(void *ptr)
7937 page = virt_to_head_page(ptr);
7938 if (put_page_testzero(page))
7939 free_compound_page(page);
7942 static void *io_mem_alloc(size_t size)
7944 gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP |
7945 __GFP_NORETRY | __GFP_ACCOUNT;
7947 return (void *) __get_free_pages(gfp_flags, get_order(size));
7950 static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
7953 struct io_rings *rings;
7954 size_t off, sq_array_size;
7956 off = struct_size(rings, cqes, cq_entries);
7957 if (off == SIZE_MAX)
7961 off = ALIGN(off, SMP_CACHE_BYTES);
7969 sq_array_size = array_size(sizeof(u32), sq_entries);
7970 if (sq_array_size == SIZE_MAX)
7973 if (check_add_overflow(off, sq_array_size, &off))
7979 static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
7983 if (!ctx->user_bufs)
7986 for (i = 0; i < ctx->nr_user_bufs; i++) {
7987 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
7989 for (j = 0; j < imu->nr_bvecs; j++)
7990 unpin_user_page(imu->bvec[j].bv_page);
7992 if (imu->acct_pages)
7993 io_unaccount_mem(ctx, imu->acct_pages);
7998 kfree(ctx->user_bufs);
7999 ctx->user_bufs = NULL;
8000 ctx->nr_user_bufs = 0;
8004 static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
8005 void __user *arg, unsigned index)
8007 struct iovec __user *src;
8009 #ifdef CONFIG_COMPAT
8011 struct compat_iovec __user *ciovs;
8012 struct compat_iovec ciov;
8014 ciovs = (struct compat_iovec __user *) arg;
8015 if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
8018 dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
8019 dst->iov_len = ciov.iov_len;
8023 src = (struct iovec __user *) arg;
8024 if (copy_from_user(dst, &src[index], sizeof(*dst)))
8030 * Not super efficient, but this is just a registration time. And we do cache
8031 * the last compound head, so generally we'll only do a full search if we don't
8034 * We check if the given compound head page has already been accounted, to
8035 * avoid double accounting it. This allows us to account the full size of the
8036 * page, not just the constituent pages of a huge page.
8038 static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
8039 int nr_pages, struct page *hpage)
8043 /* check current page array */
8044 for (i = 0; i < nr_pages; i++) {
8045 if (!PageCompound(pages[i]))
8047 if (compound_head(pages[i]) == hpage)
8051 /* check previously registered pages */
8052 for (i = 0; i < ctx->nr_user_bufs; i++) {
8053 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
8055 for (j = 0; j < imu->nr_bvecs; j++) {
8056 if (!PageCompound(imu->bvec[j].bv_page))
8058 if (compound_head(imu->bvec[j].bv_page) == hpage)
8066 static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
8067 int nr_pages, struct io_mapped_ubuf *imu,
8068 struct page **last_hpage)
8072 for (i = 0; i < nr_pages; i++) {
8073 if (!PageCompound(pages[i])) {
8078 hpage = compound_head(pages[i]);
8079 if (hpage == *last_hpage)
8081 *last_hpage = hpage;
8082 if (headpage_already_acct(ctx, pages, i, hpage))
8084 imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
8088 if (!imu->acct_pages)
8091 ret = io_account_mem(ctx, imu->acct_pages);
8093 imu->acct_pages = 0;
8097 static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
8098 struct io_mapped_ubuf *imu,
8099 struct page **last_hpage)
8101 struct vm_area_struct **vmas = NULL;
8102 struct page **pages = NULL;
8103 unsigned long off, start, end, ubuf;
8105 int ret, pret, nr_pages, i;
8107 ubuf = (unsigned long) iov->iov_base;
8108 end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
8109 start = ubuf >> PAGE_SHIFT;
8110 nr_pages = end - start;
8114 pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
8118 vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
8123 imu->bvec = kvmalloc_array(nr_pages, sizeof(struct bio_vec),
8129 mmap_read_lock(current->mm);
8130 pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
8132 if (pret == nr_pages) {
8133 /* don't support file backed memory */
8134 for (i = 0; i < nr_pages; i++) {
8135 struct vm_area_struct *vma = vmas[i];
8138 !is_file_hugepages(vma->vm_file)) {
8144 ret = pret < 0 ? pret : -EFAULT;
8146 mmap_read_unlock(current->mm);
8149 * if we did partial map, or found file backed vmas,
8150 * release any pages we did get
8153 unpin_user_pages(pages, pret);
8158 ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage);
8160 unpin_user_pages(pages, pret);
8165 off = ubuf & ~PAGE_MASK;
8166 size = iov->iov_len;
8167 for (i = 0; i < nr_pages; i++) {
8170 vec_len = min_t(size_t, size, PAGE_SIZE - off);
8171 imu->bvec[i].bv_page = pages[i];
8172 imu->bvec[i].bv_len = vec_len;
8173 imu->bvec[i].bv_offset = off;
8177 /* store original address for later verification */
8179 imu->len = iov->iov_len;
8180 imu->nr_bvecs = nr_pages;
8188 static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
8192 if (!nr_args || nr_args > UIO_MAXIOV)
8195 ctx->user_bufs = kcalloc(nr_args, sizeof(struct io_mapped_ubuf),
8197 if (!ctx->user_bufs)
8203 static int io_buffer_validate(struct iovec *iov)
8206 * Don't impose further limits on the size and buffer
8207 * constraints here, we'll -EINVAL later when IO is
8208 * submitted if they are wrong.
8210 if (!iov->iov_base || !iov->iov_len)
8213 /* arbitrary limit, but we need something */
8214 if (iov->iov_len > SZ_1G)
8220 static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
8221 unsigned int nr_args)
8225 struct page *last_hpage = NULL;
8227 ret = io_buffers_map_alloc(ctx, nr_args);
8231 for (i = 0; i < nr_args; i++) {
8232 struct io_mapped_ubuf *imu = &ctx->user_bufs[i];
8234 ret = io_copy_iov(ctx, &iov, arg, i);
8238 ret = io_buffer_validate(&iov);
8242 ret = io_sqe_buffer_register(ctx, &iov, imu, &last_hpage);
8246 ctx->nr_user_bufs++;
8250 io_sqe_buffers_unregister(ctx);
8255 static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
8257 __s32 __user *fds = arg;
8263 if (copy_from_user(&fd, fds, sizeof(*fds)))
8266 ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
8267 if (IS_ERR(ctx->cq_ev_fd)) {
8268 int ret = PTR_ERR(ctx->cq_ev_fd);
8269 ctx->cq_ev_fd = NULL;
8276 static int io_eventfd_unregister(struct io_ring_ctx *ctx)
8278 if (ctx->cq_ev_fd) {
8279 eventfd_ctx_put(ctx->cq_ev_fd);
8280 ctx->cq_ev_fd = NULL;
8287 static int __io_destroy_buffers(int id, void *p, void *data)
8289 struct io_ring_ctx *ctx = data;
8290 struct io_buffer *buf = p;
8292 __io_remove_buffers(ctx, buf, id, -1U);
8296 static void io_destroy_buffers(struct io_ring_ctx *ctx)
8298 idr_for_each(&ctx->io_buffer_idr, __io_destroy_buffers, ctx);
8299 idr_destroy(&ctx->io_buffer_idr);
8302 static void io_req_cache_free(struct list_head *list, struct task_struct *tsk)
8304 struct io_kiocb *req, *nxt;
8306 list_for_each_entry_safe(req, nxt, list, compl.list) {
8307 if (tsk && req->task != tsk)
8309 list_del(&req->compl.list);
8310 kmem_cache_free(req_cachep, req);
8314 static void io_req_caches_free(struct io_ring_ctx *ctx)
8316 struct io_submit_state *submit_state = &ctx->submit_state;
8317 struct io_comp_state *cs = &ctx->submit_state.comp;
8319 mutex_lock(&ctx->uring_lock);
8321 if (submit_state->free_reqs) {
8322 kmem_cache_free_bulk(req_cachep, submit_state->free_reqs,
8323 submit_state->reqs);
8324 submit_state->free_reqs = 0;
8327 spin_lock_irq(&ctx->completion_lock);
8328 list_splice_init(&cs->locked_free_list, &cs->free_list);
8329 cs->locked_free_nr = 0;
8330 spin_unlock_irq(&ctx->completion_lock);
8332 io_req_cache_free(&cs->free_list, NULL);
8334 mutex_unlock(&ctx->uring_lock);
8337 static void io_ring_ctx_free(struct io_ring_ctx *ctx)
8340 * Some may use context even when all refs and requests have been put,
8341 * and they are free to do so while still holding uring_lock, see
8342 * __io_req_task_submit(). Wait for them to finish.
8344 mutex_lock(&ctx->uring_lock);
8345 mutex_unlock(&ctx->uring_lock);
8347 io_sq_thread_finish(ctx);
8348 io_sqe_buffers_unregister(ctx);
8350 if (ctx->mm_account) {
8351 mmdrop(ctx->mm_account);
8352 ctx->mm_account = NULL;
8355 mutex_lock(&ctx->uring_lock);
8356 io_sqe_files_unregister(ctx);
8357 mutex_unlock(&ctx->uring_lock);
8358 io_eventfd_unregister(ctx);
8359 io_destroy_buffers(ctx);
8361 #if defined(CONFIG_UNIX)
8362 if (ctx->ring_sock) {
8363 ctx->ring_sock->file = NULL; /* so that iput() is called */
8364 sock_release(ctx->ring_sock);
8368 io_mem_free(ctx->rings);
8369 io_mem_free(ctx->sq_sqes);
8371 percpu_ref_exit(&ctx->refs);
8372 free_uid(ctx->user);
8373 io_req_caches_free(ctx);
8375 io_wq_put_hash(ctx->hash_map);
8376 kfree(ctx->cancel_hash);
8380 static __poll_t io_uring_poll(struct file *file, poll_table *wait)
8382 struct io_ring_ctx *ctx = file->private_data;
8385 poll_wait(file, &ctx->cq_wait, wait);
8387 * synchronizes with barrier from wq_has_sleeper call in
8391 if (!io_sqring_full(ctx))
8392 mask |= EPOLLOUT | EPOLLWRNORM;
8395 * Don't flush cqring overflow list here, just do a simple check.
8396 * Otherwise there could possible be ABBA deadlock:
8399 * lock(&ctx->uring_lock);
8401 * lock(&ctx->uring_lock);
8404 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
8405 * pushs them to do the flush.
8407 if (io_cqring_events(ctx) || test_bit(0, &ctx->cq_check_overflow))
8408 mask |= EPOLLIN | EPOLLRDNORM;
8413 static int io_uring_fasync(int fd, struct file *file, int on)
8415 struct io_ring_ctx *ctx = file->private_data;
8417 return fasync_helper(fd, file, on, &ctx->cq_fasync);
8420 static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
8422 const struct cred *creds;
8424 creds = xa_erase(&ctx->personalities, id);
8433 static bool io_run_ctx_fallback(struct io_ring_ctx *ctx)
8435 struct callback_head *work, *next;
8436 bool executed = false;
8439 work = xchg(&ctx->exit_task_work, NULL);
8455 struct io_tctx_exit {
8456 struct callback_head task_work;
8457 struct completion completion;
8458 struct io_ring_ctx *ctx;
8461 static void io_tctx_exit_cb(struct callback_head *cb)
8463 struct io_uring_task *tctx = current->io_uring;
8464 struct io_tctx_exit *work;
8466 work = container_of(cb, struct io_tctx_exit, task_work);
8468 * When @in_idle, we're in cancellation and it's racy to remove the
8469 * node. It'll be removed by the end of cancellation, just ignore it.
8471 if (!atomic_read(&tctx->in_idle))
8472 io_uring_del_task_file((unsigned long)work->ctx);
8473 complete(&work->completion);
8476 static void io_ring_exit_work(struct work_struct *work)
8478 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
8479 unsigned long timeout = jiffies + HZ * 60 * 5;
8480 struct io_tctx_exit exit;
8481 struct io_tctx_node *node;
8485 * If we're doing polled IO and end up having requests being
8486 * submitted async (out-of-line), then completions can come in while
8487 * we're waiting for refs to drop. We need to reap these manually,
8488 * as nobody else will be looking for them.
8491 io_uring_try_cancel_requests(ctx, NULL, NULL);
8493 WARN_ON_ONCE(time_after(jiffies, timeout));
8494 } while (!wait_for_completion_timeout(&ctx->ref_comp, HZ/20));
8496 mutex_lock(&ctx->uring_lock);
8497 while (!list_empty(&ctx->tctx_list)) {
8498 WARN_ON_ONCE(time_after(jiffies, timeout));
8500 node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
8503 init_completion(&exit.completion);
8504 init_task_work(&exit.task_work, io_tctx_exit_cb);
8505 ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
8506 if (WARN_ON_ONCE(ret))
8508 wake_up_process(node->task);
8510 mutex_unlock(&ctx->uring_lock);
8511 wait_for_completion(&exit.completion);
8513 mutex_lock(&ctx->uring_lock);
8515 mutex_unlock(&ctx->uring_lock);
8517 io_ring_ctx_free(ctx);
8520 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
8522 unsigned long index;
8523 struct creds *creds;
8525 mutex_lock(&ctx->uring_lock);
8526 percpu_ref_kill(&ctx->refs);
8527 /* if force is set, the ring is going away. always drop after that */
8528 ctx->cq_overflow_flushed = 1;
8530 __io_cqring_overflow_flush(ctx, true, NULL, NULL);
8531 xa_for_each(&ctx->personalities, index, creds)
8532 io_unregister_personality(ctx, index);
8533 mutex_unlock(&ctx->uring_lock);
8535 io_kill_timeouts(ctx, NULL, NULL);
8536 io_poll_remove_all(ctx, NULL, NULL);
8538 /* if we failed setting up the ctx, we might not have any rings */
8539 io_iopoll_try_reap_events(ctx);
8541 INIT_WORK(&ctx->exit_work, io_ring_exit_work);
8543 * Use system_unbound_wq to avoid spawning tons of event kworkers
8544 * if we're exiting a ton of rings at the same time. It just adds
8545 * noise and overhead, there's no discernable change in runtime
8546 * over using system_wq.
8548 queue_work(system_unbound_wq, &ctx->exit_work);
8551 static int io_uring_release(struct inode *inode, struct file *file)
8553 struct io_ring_ctx *ctx = file->private_data;
8555 file->private_data = NULL;
8556 io_ring_ctx_wait_and_kill(ctx);
8560 struct io_task_cancel {
8561 struct task_struct *task;
8562 struct files_struct *files;
8565 static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
8567 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8568 struct io_task_cancel *cancel = data;
8571 if (cancel->files && (req->flags & REQ_F_LINK_TIMEOUT)) {
8572 unsigned long flags;
8573 struct io_ring_ctx *ctx = req->ctx;
8575 /* protect against races with linked timeouts */
8576 spin_lock_irqsave(&ctx->completion_lock, flags);
8577 ret = io_match_task(req, cancel->task, cancel->files);
8578 spin_unlock_irqrestore(&ctx->completion_lock, flags);
8580 ret = io_match_task(req, cancel->task, cancel->files);
8585 static void io_cancel_defer_files(struct io_ring_ctx *ctx,
8586 struct task_struct *task,
8587 struct files_struct *files)
8589 struct io_defer_entry *de = NULL;
8592 spin_lock_irq(&ctx->completion_lock);
8593 list_for_each_entry_reverse(de, &ctx->defer_list, list) {
8594 if (io_match_task(de->req, task, files)) {
8595 list_cut_position(&list, &ctx->defer_list, &de->list);
8599 spin_unlock_irq(&ctx->completion_lock);
8601 while (!list_empty(&list)) {
8602 de = list_first_entry(&list, struct io_defer_entry, list);
8603 list_del_init(&de->list);
8604 req_set_fail_links(de->req);
8605 io_put_req(de->req);
8606 io_req_complete(de->req, -ECANCELED);
8611 static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
8613 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8615 return req->ctx == data;
8618 static bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
8620 struct io_tctx_node *node;
8621 enum io_wq_cancel cret;
8624 mutex_lock(&ctx->uring_lock);
8625 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
8626 struct io_uring_task *tctx = node->task->io_uring;
8629 * io_wq will stay alive while we hold uring_lock, because it's
8630 * killed after ctx nodes, which requires to take the lock.
8632 if (!tctx || !tctx->io_wq)
8634 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
8635 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
8637 mutex_unlock(&ctx->uring_lock);
8642 static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
8643 struct task_struct *task,
8644 struct files_struct *files)
8646 struct io_task_cancel cancel = { .task = task, .files = files, };
8647 struct io_uring_task *tctx = task ? task->io_uring : NULL;
8650 enum io_wq_cancel cret;
8654 ret |= io_uring_try_cancel_iowq(ctx);
8655 } else if (tctx && tctx->io_wq) {
8657 * Cancels requests of all rings, not only @ctx, but
8658 * it's fine as the task is in exit/exec.
8660 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
8662 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
8665 /* SQPOLL thread does its own polling */
8666 if (!(ctx->flags & IORING_SETUP_SQPOLL) && !files) {
8667 while (!list_empty_careful(&ctx->iopoll_list)) {
8668 io_iopoll_try_reap_events(ctx);
8673 ret |= io_poll_remove_all(ctx, task, files);
8674 ret |= io_kill_timeouts(ctx, task, files);
8675 ret |= io_run_task_work();
8676 ret |= io_run_ctx_fallback(ctx);
8677 io_cqring_overflow_flush(ctx, true, task, files);
8684 static int io_uring_count_inflight(struct io_ring_ctx *ctx,
8685 struct task_struct *task,
8686 struct files_struct *files)
8688 struct io_kiocb *req;
8691 spin_lock_irq(&ctx->inflight_lock);
8692 list_for_each_entry(req, &ctx->inflight_list, inflight_entry)
8693 cnt += io_match_task(req, task, files);
8694 spin_unlock_irq(&ctx->inflight_lock);
8698 static void io_uring_cancel_files(struct io_ring_ctx *ctx,
8699 struct task_struct *task,
8700 struct files_struct *files)
8702 while (!list_empty_careful(&ctx->inflight_list)) {
8706 inflight = io_uring_count_inflight(ctx, task, files);
8710 io_uring_try_cancel_requests(ctx, task, files);
8713 io_sq_thread_unpark(ctx->sq_data);
8714 prepare_to_wait(&task->io_uring->wait, &wait,
8715 TASK_UNINTERRUPTIBLE);
8716 if (inflight == io_uring_count_inflight(ctx, task, files))
8718 finish_wait(&task->io_uring->wait, &wait);
8720 io_sq_thread_park(ctx->sq_data);
8725 * We need to iteratively cancel requests, in case a request has dependent
8726 * hard links. These persist even for failure of cancelations, hence keep
8727 * looping until none are found.
8729 static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx,
8730 struct files_struct *files)
8732 struct task_struct *task = current;
8734 if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) {
8735 io_sq_thread_park(ctx->sq_data);
8736 task = ctx->sq_data->thread;
8738 atomic_inc(&task->io_uring->in_idle);
8741 io_cancel_defer_files(ctx, task, files);
8743 io_uring_cancel_files(ctx, task, files);
8745 io_uring_try_cancel_requests(ctx, task, NULL);
8748 atomic_dec(&task->io_uring->in_idle);
8750 io_sq_thread_unpark(ctx->sq_data);
8754 * Note that this task has used io_uring. We use it for cancelation purposes.
8756 static int io_uring_add_task_file(struct io_ring_ctx *ctx)
8758 struct io_uring_task *tctx = current->io_uring;
8759 struct io_tctx_node *node;
8762 if (unlikely(!tctx)) {
8763 ret = io_uring_alloc_task_context(current, ctx);
8766 tctx = current->io_uring;
8768 if (tctx->last != ctx) {
8769 void *old = xa_load(&tctx->xa, (unsigned long)ctx);
8772 node = kmalloc(sizeof(*node), GFP_KERNEL);
8776 node->task = current;
8778 ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
8785 mutex_lock(&ctx->uring_lock);
8786 list_add(&node->ctx_node, &ctx->tctx_list);
8787 mutex_unlock(&ctx->uring_lock);
8793 * This is race safe in that the task itself is doing this, hence it
8794 * cannot be going through the exit/cancel paths at the same time.
8795 * This cannot be modified while exit/cancel is running.
8797 if (!tctx->sqpoll && (ctx->flags & IORING_SETUP_SQPOLL))
8798 tctx->sqpoll = true;
8804 * Remove this io_uring_file -> task mapping.
8806 static void io_uring_del_task_file(unsigned long index)
8808 struct io_uring_task *tctx = current->io_uring;
8809 struct io_tctx_node *node;
8813 node = xa_erase(&tctx->xa, index);
8817 WARN_ON_ONCE(current != node->task);
8818 WARN_ON_ONCE(list_empty(&node->ctx_node));
8820 mutex_lock(&node->ctx->uring_lock);
8821 list_del(&node->ctx_node);
8822 mutex_unlock(&node->ctx->uring_lock);
8824 if (tctx->last == node->ctx)
8829 static void io_uring_clean_tctx(struct io_uring_task *tctx)
8831 struct io_tctx_node *node;
8832 unsigned long index;
8834 xa_for_each(&tctx->xa, index, node)
8835 io_uring_del_task_file(index);
8837 io_wq_put_and_exit(tctx->io_wq);
8842 void __io_uring_files_cancel(struct files_struct *files)
8844 struct io_uring_task *tctx = current->io_uring;
8845 struct io_tctx_node *node;
8846 unsigned long index;
8848 /* make sure overflow events are dropped */
8849 atomic_inc(&tctx->in_idle);
8850 xa_for_each(&tctx->xa, index, node)
8851 io_uring_cancel_task_requests(node->ctx, files);
8852 atomic_dec(&tctx->in_idle);
8855 io_uring_clean_tctx(tctx);
8858 static s64 tctx_inflight(struct io_uring_task *tctx)
8860 return percpu_counter_sum(&tctx->inflight);
8863 static void io_uring_cancel_sqpoll(struct io_ring_ctx *ctx)
8865 struct io_sq_data *sqd = ctx->sq_data;
8866 struct io_uring_task *tctx;
8872 io_sq_thread_park(sqd);
8873 if (!sqd->thread || !sqd->thread->io_uring) {
8874 io_sq_thread_unpark(sqd);
8877 tctx = ctx->sq_data->thread->io_uring;
8878 atomic_inc(&tctx->in_idle);
8880 /* read completions before cancelations */
8881 inflight = tctx_inflight(tctx);
8884 io_uring_cancel_task_requests(ctx, NULL);
8886 prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
8888 * If we've seen completions, retry without waiting. This
8889 * avoids a race where a completion comes in before we did
8890 * prepare_to_wait().
8892 if (inflight == tctx_inflight(tctx))
8894 finish_wait(&tctx->wait, &wait);
8896 atomic_dec(&tctx->in_idle);
8897 io_sq_thread_unpark(sqd);
8901 * Find any io_uring fd that this task has registered or done IO on, and cancel
8904 void __io_uring_task_cancel(void)
8906 struct io_uring_task *tctx = current->io_uring;
8910 /* make sure overflow events are dropped */
8911 atomic_inc(&tctx->in_idle);
8914 struct io_tctx_node *node;
8915 unsigned long index;
8917 xa_for_each(&tctx->xa, index, node)
8918 io_uring_cancel_sqpoll(node->ctx);
8922 /* read completions before cancelations */
8923 inflight = tctx_inflight(tctx);
8926 __io_uring_files_cancel(NULL);
8928 prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
8931 * If we've seen completions, retry without waiting. This
8932 * avoids a race where a completion comes in before we did
8933 * prepare_to_wait().
8935 if (inflight == tctx_inflight(tctx))
8937 finish_wait(&tctx->wait, &wait);
8940 atomic_dec(&tctx->in_idle);
8942 io_uring_clean_tctx(tctx);
8943 /* all current's requests should be gone, we can kill tctx */
8944 __io_uring_free(current);
8947 static void *io_uring_validate_mmap_request(struct file *file,
8948 loff_t pgoff, size_t sz)
8950 struct io_ring_ctx *ctx = file->private_data;
8951 loff_t offset = pgoff << PAGE_SHIFT;
8956 case IORING_OFF_SQ_RING:
8957 case IORING_OFF_CQ_RING:
8960 case IORING_OFF_SQES:
8964 return ERR_PTR(-EINVAL);
8967 page = virt_to_head_page(ptr);
8968 if (sz > page_size(page))
8969 return ERR_PTR(-EINVAL);
8976 static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
8978 size_t sz = vma->vm_end - vma->vm_start;
8982 ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
8984 return PTR_ERR(ptr);
8986 pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
8987 return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
8990 #else /* !CONFIG_MMU */
8992 static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
8994 return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
8997 static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
8999 return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
9002 static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
9003 unsigned long addr, unsigned long len,
9004 unsigned long pgoff, unsigned long flags)
9008 ptr = io_uring_validate_mmap_request(file, pgoff, len);
9010 return PTR_ERR(ptr);
9012 return (unsigned long) ptr;
9015 #endif /* !CONFIG_MMU */
9017 static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
9023 if (!io_sqring_full(ctx))
9025 prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
9027 if (!io_sqring_full(ctx))
9030 } while (!signal_pending(current));
9032 finish_wait(&ctx->sqo_sq_wait, &wait);
9036 static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
9037 struct __kernel_timespec __user **ts,
9038 const sigset_t __user **sig)
9040 struct io_uring_getevents_arg arg;
9043 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9044 * is just a pointer to the sigset_t.
9046 if (!(flags & IORING_ENTER_EXT_ARG)) {
9047 *sig = (const sigset_t __user *) argp;
9053 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9054 * timespec and sigset_t pointers if good.
9056 if (*argsz != sizeof(arg))
9058 if (copy_from_user(&arg, argp, sizeof(arg)))
9060 *sig = u64_to_user_ptr(arg.sigmask);
9061 *argsz = arg.sigmask_sz;
9062 *ts = u64_to_user_ptr(arg.ts);
9066 SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
9067 u32, min_complete, u32, flags, const void __user *, argp,
9070 struct io_ring_ctx *ctx;
9077 if (flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
9078 IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG))
9086 if (f.file->f_op != &io_uring_fops)
9090 ctx = f.file->private_data;
9091 if (!percpu_ref_tryget(&ctx->refs))
9095 if (ctx->flags & IORING_SETUP_R_DISABLED)
9099 * For SQ polling, the thread will do all submissions and completions.
9100 * Just return the requested submit count, and wake the thread if
9104 if (ctx->flags & IORING_SETUP_SQPOLL) {
9105 io_cqring_overflow_flush(ctx, false, NULL, NULL);
9108 if (unlikely(ctx->sq_data->thread == NULL)) {
9111 if (flags & IORING_ENTER_SQ_WAKEUP)
9112 wake_up(&ctx->sq_data->wait);
9113 if (flags & IORING_ENTER_SQ_WAIT) {
9114 ret = io_sqpoll_wait_sq(ctx);
9118 submitted = to_submit;
9119 } else if (to_submit) {
9120 ret = io_uring_add_task_file(ctx);
9123 mutex_lock(&ctx->uring_lock);
9124 submitted = io_submit_sqes(ctx, to_submit);
9125 mutex_unlock(&ctx->uring_lock);
9127 if (submitted != to_submit)
9130 if (flags & IORING_ENTER_GETEVENTS) {
9131 const sigset_t __user *sig;
9132 struct __kernel_timespec __user *ts;
9134 ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
9138 min_complete = min(min_complete, ctx->cq_entries);
9141 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9142 * space applications don't need to do io completion events
9143 * polling again, they can rely on io_sq_thread to do polling
9144 * work, which can reduce cpu usage and uring_lock contention.
9146 if (ctx->flags & IORING_SETUP_IOPOLL &&
9147 !(ctx->flags & IORING_SETUP_SQPOLL)) {
9148 ret = io_iopoll_check(ctx, min_complete);
9150 ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts);
9155 percpu_ref_put(&ctx->refs);
9158 return submitted ? submitted : ret;
9161 #ifdef CONFIG_PROC_FS
9162 static int io_uring_show_cred(struct seq_file *m, unsigned int id,
9163 const struct cred *cred)
9165 struct user_namespace *uns = seq_user_ns(m);
9166 struct group_info *gi;
9171 seq_printf(m, "%5d\n", id);
9172 seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
9173 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
9174 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
9175 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
9176 seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
9177 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
9178 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
9179 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
9180 seq_puts(m, "\n\tGroups:\t");
9181 gi = cred->group_info;
9182 for (g = 0; g < gi->ngroups; g++) {
9183 seq_put_decimal_ull(m, g ? " " : "",
9184 from_kgid_munged(uns, gi->gid[g]));
9186 seq_puts(m, "\n\tCapEff:\t");
9187 cap = cred->cap_effective;
9188 CAP_FOR_EACH_U32(__capi)
9189 seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
9194 static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
9196 struct io_sq_data *sq = NULL;
9201 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9202 * since fdinfo case grabs it in the opposite direction of normal use
9203 * cases. If we fail to get the lock, we just don't iterate any
9204 * structures that could be going away outside the io_uring mutex.
9206 has_lock = mutex_trylock(&ctx->uring_lock);
9208 if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
9214 seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
9215 seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
9216 seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
9217 for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
9218 struct file *f = *io_fixed_file_slot(ctx->file_data, i);
9221 seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
9223 seq_printf(m, "%5u: <none>\n", i);
9225 seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
9226 for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
9227 struct io_mapped_ubuf *buf = &ctx->user_bufs[i];
9229 seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf,
9230 (unsigned int) buf->len);
9232 if (has_lock && !xa_empty(&ctx->personalities)) {
9233 unsigned long index;
9234 const struct cred *cred;
9236 seq_printf(m, "Personalities:\n");
9237 xa_for_each(&ctx->personalities, index, cred)
9238 io_uring_show_cred(m, index, cred);
9240 seq_printf(m, "PollList:\n");
9241 spin_lock_irq(&ctx->completion_lock);
9242 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
9243 struct hlist_head *list = &ctx->cancel_hash[i];
9244 struct io_kiocb *req;
9246 hlist_for_each_entry(req, list, hash_node)
9247 seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
9248 req->task->task_works != NULL);
9250 spin_unlock_irq(&ctx->completion_lock);
9252 mutex_unlock(&ctx->uring_lock);
9255 static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
9257 struct io_ring_ctx *ctx = f->private_data;
9259 if (percpu_ref_tryget(&ctx->refs)) {
9260 __io_uring_show_fdinfo(ctx, m);
9261 percpu_ref_put(&ctx->refs);
9266 static const struct file_operations io_uring_fops = {
9267 .release = io_uring_release,
9268 .mmap = io_uring_mmap,
9270 .get_unmapped_area = io_uring_nommu_get_unmapped_area,
9271 .mmap_capabilities = io_uring_nommu_mmap_capabilities,
9273 .poll = io_uring_poll,
9274 .fasync = io_uring_fasync,
9275 #ifdef CONFIG_PROC_FS
9276 .show_fdinfo = io_uring_show_fdinfo,
9280 static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
9281 struct io_uring_params *p)
9283 struct io_rings *rings;
9284 size_t size, sq_array_offset;
9286 /* make sure these are sane, as we already accounted them */
9287 ctx->sq_entries = p->sq_entries;
9288 ctx->cq_entries = p->cq_entries;
9290 size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
9291 if (size == SIZE_MAX)
9294 rings = io_mem_alloc(size);
9299 ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
9300 rings->sq_ring_mask = p->sq_entries - 1;
9301 rings->cq_ring_mask = p->cq_entries - 1;
9302 rings->sq_ring_entries = p->sq_entries;
9303 rings->cq_ring_entries = p->cq_entries;
9304 ctx->sq_mask = rings->sq_ring_mask;
9305 ctx->cq_mask = rings->cq_ring_mask;
9307 size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
9308 if (size == SIZE_MAX) {
9309 io_mem_free(ctx->rings);
9314 ctx->sq_sqes = io_mem_alloc(size);
9315 if (!ctx->sq_sqes) {
9316 io_mem_free(ctx->rings);
9324 static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
9328 fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
9332 ret = io_uring_add_task_file(ctx);
9337 fd_install(fd, file);
9342 * Allocate an anonymous fd, this is what constitutes the application
9343 * visible backing of an io_uring instance. The application mmaps this
9344 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9345 * we have to tie this fd to a socket for file garbage collection purposes.
9347 static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
9350 #if defined(CONFIG_UNIX)
9353 ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
9356 return ERR_PTR(ret);
9359 file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
9360 O_RDWR | O_CLOEXEC);
9361 #if defined(CONFIG_UNIX)
9363 sock_release(ctx->ring_sock);
9364 ctx->ring_sock = NULL;
9366 ctx->ring_sock->file = file;
9372 static int io_uring_create(unsigned entries, struct io_uring_params *p,
9373 struct io_uring_params __user *params)
9375 struct io_ring_ctx *ctx;
9381 if (entries > IORING_MAX_ENTRIES) {
9382 if (!(p->flags & IORING_SETUP_CLAMP))
9384 entries = IORING_MAX_ENTRIES;
9388 * Use twice as many entries for the CQ ring. It's possible for the
9389 * application to drive a higher depth than the size of the SQ ring,
9390 * since the sqes are only used at submission time. This allows for
9391 * some flexibility in overcommitting a bit. If the application has
9392 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9393 * of CQ ring entries manually.
9395 p->sq_entries = roundup_pow_of_two(entries);
9396 if (p->flags & IORING_SETUP_CQSIZE) {
9398 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9399 * to a power-of-two, if it isn't already. We do NOT impose
9400 * any cq vs sq ring sizing.
9404 if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
9405 if (!(p->flags & IORING_SETUP_CLAMP))
9407 p->cq_entries = IORING_MAX_CQ_ENTRIES;
9409 p->cq_entries = roundup_pow_of_two(p->cq_entries);
9410 if (p->cq_entries < p->sq_entries)
9413 p->cq_entries = 2 * p->sq_entries;
9416 ctx = io_ring_ctx_alloc(p);
9419 ctx->compat = in_compat_syscall();
9420 if (!capable(CAP_IPC_LOCK))
9421 ctx->user = get_uid(current_user());
9424 * This is just grabbed for accounting purposes. When a process exits,
9425 * the mm is exited and dropped before the files, hence we need to hang
9426 * on to this mm purely for the purposes of being able to unaccount
9427 * memory (locked/pinned vm). It's not used for anything else.
9429 mmgrab(current->mm);
9430 ctx->mm_account = current->mm;
9432 ret = io_allocate_scq_urings(ctx, p);
9436 ret = io_sq_offload_create(ctx, p);
9440 memset(&p->sq_off, 0, sizeof(p->sq_off));
9441 p->sq_off.head = offsetof(struct io_rings, sq.head);
9442 p->sq_off.tail = offsetof(struct io_rings, sq.tail);
9443 p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
9444 p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
9445 p->sq_off.flags = offsetof(struct io_rings, sq_flags);
9446 p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
9447 p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
9449 memset(&p->cq_off, 0, sizeof(p->cq_off));
9450 p->cq_off.head = offsetof(struct io_rings, cq.head);
9451 p->cq_off.tail = offsetof(struct io_rings, cq.tail);
9452 p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
9453 p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
9454 p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
9455 p->cq_off.cqes = offsetof(struct io_rings, cqes);
9456 p->cq_off.flags = offsetof(struct io_rings, cq_flags);
9458 p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
9459 IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
9460 IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
9461 IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
9462 IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS;
9464 if (copy_to_user(params, p, sizeof(*p))) {
9469 file = io_uring_get_file(ctx);
9471 ret = PTR_ERR(file);
9476 * Install ring fd as the very last thing, so we don't risk someone
9477 * having closed it before we finish setup
9479 ret = io_uring_install_fd(ctx, file);
9481 /* fput will clean it up */
9486 trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
9489 io_ring_ctx_wait_and_kill(ctx);
9494 * Sets up an aio uring context, and returns the fd. Applications asks for a
9495 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9496 * params structure passed in.
9498 static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
9500 struct io_uring_params p;
9503 if (copy_from_user(&p, params, sizeof(p)))
9505 for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
9510 if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
9511 IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
9512 IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
9513 IORING_SETUP_R_DISABLED))
9516 return io_uring_create(entries, &p, params);
9519 SYSCALL_DEFINE2(io_uring_setup, u32, entries,
9520 struct io_uring_params __user *, params)
9522 return io_uring_setup(entries, params);
9525 static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
9527 struct io_uring_probe *p;
9531 size = struct_size(p, ops, nr_args);
9532 if (size == SIZE_MAX)
9534 p = kzalloc(size, GFP_KERNEL);
9539 if (copy_from_user(p, arg, size))
9542 if (memchr_inv(p, 0, size))
9545 p->last_op = IORING_OP_LAST - 1;
9546 if (nr_args > IORING_OP_LAST)
9547 nr_args = IORING_OP_LAST;
9549 for (i = 0; i < nr_args; i++) {
9551 if (!io_op_defs[i].not_supported)
9552 p->ops[i].flags = IO_URING_OP_SUPPORTED;
9557 if (copy_to_user(arg, p, size))
9564 static int io_register_personality(struct io_ring_ctx *ctx)
9566 const struct cred *creds;
9570 creds = get_current_cred();
9572 ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
9573 XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
9580 static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
9581 unsigned int nr_args)
9583 struct io_uring_restriction *res;
9587 /* Restrictions allowed only if rings started disabled */
9588 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
9591 /* We allow only a single restrictions registration */
9592 if (ctx->restrictions.registered)
9595 if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
9598 size = array_size(nr_args, sizeof(*res));
9599 if (size == SIZE_MAX)
9602 res = memdup_user(arg, size);
9604 return PTR_ERR(res);
9608 for (i = 0; i < nr_args; i++) {
9609 switch (res[i].opcode) {
9610 case IORING_RESTRICTION_REGISTER_OP:
9611 if (res[i].register_op >= IORING_REGISTER_LAST) {
9616 __set_bit(res[i].register_op,
9617 ctx->restrictions.register_op);
9619 case IORING_RESTRICTION_SQE_OP:
9620 if (res[i].sqe_op >= IORING_OP_LAST) {
9625 __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
9627 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
9628 ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
9630 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
9631 ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
9640 /* Reset all restrictions if an error happened */
9642 memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
9644 ctx->restrictions.registered = true;
9650 static int io_register_enable_rings(struct io_ring_ctx *ctx)
9652 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
9655 if (ctx->restrictions.registered)
9656 ctx->restricted = 1;
9658 ctx->flags &= ~IORING_SETUP_R_DISABLED;
9659 if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
9660 wake_up(&ctx->sq_data->wait);
9664 static bool io_register_op_must_quiesce(int op)
9667 case IORING_UNREGISTER_FILES:
9668 case IORING_REGISTER_FILES_UPDATE:
9669 case IORING_REGISTER_PROBE:
9670 case IORING_REGISTER_PERSONALITY:
9671 case IORING_UNREGISTER_PERSONALITY:
9678 static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
9679 void __user *arg, unsigned nr_args)
9680 __releases(ctx->uring_lock)
9681 __acquires(ctx->uring_lock)
9686 * We're inside the ring mutex, if the ref is already dying, then
9687 * someone else killed the ctx or is already going through
9688 * io_uring_register().
9690 if (percpu_ref_is_dying(&ctx->refs))
9693 if (io_register_op_must_quiesce(opcode)) {
9694 percpu_ref_kill(&ctx->refs);
9697 * Drop uring mutex before waiting for references to exit. If
9698 * another thread is currently inside io_uring_enter() it might
9699 * need to grab the uring_lock to make progress. If we hold it
9700 * here across the drain wait, then we can deadlock. It's safe
9701 * to drop the mutex here, since no new references will come in
9702 * after we've killed the percpu ref.
9704 mutex_unlock(&ctx->uring_lock);
9706 ret = wait_for_completion_interruptible(&ctx->ref_comp);
9709 ret = io_run_task_work_sig();
9714 mutex_lock(&ctx->uring_lock);
9717 percpu_ref_resurrect(&ctx->refs);
9722 if (ctx->restricted) {
9723 if (opcode >= IORING_REGISTER_LAST) {
9728 if (!test_bit(opcode, ctx->restrictions.register_op)) {
9735 case IORING_REGISTER_BUFFERS:
9736 ret = io_sqe_buffers_register(ctx, arg, nr_args);
9738 case IORING_UNREGISTER_BUFFERS:
9742 ret = io_sqe_buffers_unregister(ctx);
9744 case IORING_REGISTER_FILES:
9745 ret = io_sqe_files_register(ctx, arg, nr_args);
9747 case IORING_UNREGISTER_FILES:
9751 ret = io_sqe_files_unregister(ctx);
9753 case IORING_REGISTER_FILES_UPDATE:
9754 ret = io_sqe_files_update(ctx, arg, nr_args);
9756 case IORING_REGISTER_EVENTFD:
9757 case IORING_REGISTER_EVENTFD_ASYNC:
9761 ret = io_eventfd_register(ctx, arg);
9764 if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
9765 ctx->eventfd_async = 1;
9767 ctx->eventfd_async = 0;
9769 case IORING_UNREGISTER_EVENTFD:
9773 ret = io_eventfd_unregister(ctx);
9775 case IORING_REGISTER_PROBE:
9777 if (!arg || nr_args > 256)
9779 ret = io_probe(ctx, arg, nr_args);
9781 case IORING_REGISTER_PERSONALITY:
9785 ret = io_register_personality(ctx);
9787 case IORING_UNREGISTER_PERSONALITY:
9791 ret = io_unregister_personality(ctx, nr_args);
9793 case IORING_REGISTER_ENABLE_RINGS:
9797 ret = io_register_enable_rings(ctx);
9799 case IORING_REGISTER_RESTRICTIONS:
9800 ret = io_register_restrictions(ctx, arg, nr_args);
9808 if (io_register_op_must_quiesce(opcode)) {
9809 /* bring the ctx back to life */
9810 percpu_ref_reinit(&ctx->refs);
9812 reinit_completion(&ctx->ref_comp);
9817 SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
9818 void __user *, arg, unsigned int, nr_args)
9820 struct io_ring_ctx *ctx;
9829 if (f.file->f_op != &io_uring_fops)
9832 ctx = f.file->private_data;
9836 mutex_lock(&ctx->uring_lock);
9837 ret = __io_uring_register(ctx, opcode, arg, nr_args);
9838 mutex_unlock(&ctx->uring_lock);
9839 trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
9840 ctx->cq_ev_fd != NULL, ret);
9846 static int __init io_uring_init(void)
9848 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
9849 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
9850 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
9853 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
9854 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
9855 BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
9856 BUILD_BUG_SQE_ELEM(0, __u8, opcode);
9857 BUILD_BUG_SQE_ELEM(1, __u8, flags);
9858 BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
9859 BUILD_BUG_SQE_ELEM(4, __s32, fd);
9860 BUILD_BUG_SQE_ELEM(8, __u64, off);
9861 BUILD_BUG_SQE_ELEM(8, __u64, addr2);
9862 BUILD_BUG_SQE_ELEM(16, __u64, addr);
9863 BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
9864 BUILD_BUG_SQE_ELEM(24, __u32, len);
9865 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
9866 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
9867 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
9868 BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
9869 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
9870 BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
9871 BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
9872 BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
9873 BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
9874 BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
9875 BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
9876 BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
9877 BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
9878 BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
9879 BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
9880 BUILD_BUG_SQE_ELEM(32, __u64, user_data);
9881 BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
9882 BUILD_BUG_SQE_ELEM(42, __u16, personality);
9883 BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
9885 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
9886 BUILD_BUG_ON(__REQ_F_LAST_BIT >= 8 * sizeof(int));
9887 req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
9891 __initcall(io_uring_init);