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_cqe (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/tracehook.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)
93 #define IORING_SQPOLL_CAP_ENTRIES_VALUE 8
95 /* 512 entries per page on 64-bit archs, 64 pages max */
96 #define IORING_MAX_FIXED_FILES (1U << 15)
97 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
98 IORING_REGISTER_LAST + IORING_OP_LAST)
100 #define IO_RSRC_TAG_TABLE_SHIFT 9
101 #define IO_RSRC_TAG_TABLE_MAX (1U << IO_RSRC_TAG_TABLE_SHIFT)
102 #define IO_RSRC_TAG_TABLE_MASK (IO_RSRC_TAG_TABLE_MAX - 1)
104 #define IORING_MAX_REG_BUFFERS (1U << 14)
106 #define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \
107 IOSQE_IO_HARDLINK | IOSQE_ASYNC | \
109 #define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
110 REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS)
112 #define IO_TCTX_REFS_CACHE_NR (1U << 10)
115 u32 head ____cacheline_aligned_in_smp;
116 u32 tail ____cacheline_aligned_in_smp;
120 * This data is shared with the application through the mmap at offsets
121 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
123 * The offsets to the member fields are published through struct
124 * io_sqring_offsets when calling io_uring_setup.
128 * Head and tail offsets into the ring; the offsets need to be
129 * masked to get valid indices.
131 * The kernel controls head of the sq ring and the tail of the cq ring,
132 * and the application controls tail of the sq ring and the head of the
135 struct io_uring sq, cq;
137 * Bitmasks to apply to head and tail offsets (constant, equals
140 u32 sq_ring_mask, cq_ring_mask;
141 /* Ring sizes (constant, power of 2) */
142 u32 sq_ring_entries, cq_ring_entries;
144 * Number of invalid entries dropped by the kernel due to
145 * invalid index stored in array
147 * Written by the kernel, shouldn't be modified by the
148 * application (i.e. get number of "new events" by comparing to
151 * After a new SQ head value was read by the application this
152 * counter includes all submissions that were dropped reaching
153 * the new SQ head (and possibly more).
159 * Written by the kernel, shouldn't be modified by the
162 * The application needs a full memory barrier before checking
163 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
169 * Written by the application, shouldn't be modified by the
174 * Number of completion events lost because the queue was full;
175 * this should be avoided by the application by making sure
176 * there are not more requests pending than there is space in
177 * the completion queue.
179 * Written by the kernel, shouldn't be modified by the
180 * application (i.e. get number of "new events" by comparing to
183 * As completion events come in out of order this counter is not
184 * ordered with any other data.
188 * Ring buffer of completion events.
190 * The kernel writes completion events fresh every time they are
191 * produced, so the application is allowed to modify pending
194 struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp;
197 enum io_uring_cmd_flags {
198 IO_URING_F_NONBLOCK = 1,
199 IO_URING_F_COMPLETE_DEFER = 2,
202 struct io_mapped_ubuf {
205 unsigned int nr_bvecs;
206 unsigned long acct_pages;
207 struct bio_vec bvec[];
212 struct io_overflow_cqe {
213 struct io_uring_cqe cqe;
214 struct list_head list;
217 struct io_fixed_file {
218 /* file * with additional FFS_* flags */
219 unsigned long file_ptr;
223 struct list_head list;
228 struct io_mapped_ubuf *buf;
232 struct io_file_table {
233 struct io_fixed_file *files;
236 struct io_rsrc_node {
237 struct percpu_ref refs;
238 struct list_head node;
239 struct list_head rsrc_list;
240 struct io_rsrc_data *rsrc_data;
241 struct llist_node llist;
245 typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
247 struct io_rsrc_data {
248 struct io_ring_ctx *ctx;
254 struct completion done;
259 struct list_head list;
265 struct io_restriction {
266 DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
267 DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
268 u8 sqe_flags_allowed;
269 u8 sqe_flags_required;
274 IO_SQ_THREAD_SHOULD_STOP = 0,
275 IO_SQ_THREAD_SHOULD_PARK,
280 atomic_t park_pending;
283 /* ctx's that are using this sqd */
284 struct list_head ctx_list;
286 struct task_struct *thread;
287 struct wait_queue_head wait;
289 unsigned sq_thread_idle;
295 struct completion exited;
298 #define IO_COMPL_BATCH 32
299 #define IO_REQ_CACHE_SIZE 32
300 #define IO_REQ_ALLOC_BATCH 8
302 struct io_submit_link {
303 struct io_kiocb *head;
304 struct io_kiocb *last;
307 struct io_submit_state {
308 struct blk_plug plug;
309 struct io_submit_link link;
312 * io_kiocb alloc cache
314 void *reqs[IO_REQ_CACHE_SIZE];
315 unsigned int free_reqs;
320 * Batch completion logic
322 struct io_kiocb *compl_reqs[IO_COMPL_BATCH];
323 unsigned int compl_nr;
324 /* inline/task_work completion list, under ->uring_lock */
325 struct list_head free_list;
327 unsigned int ios_left;
331 /* const or read-mostly hot data */
333 struct percpu_ref refs;
335 struct io_rings *rings;
337 unsigned int compat: 1;
338 unsigned int drain_next: 1;
339 unsigned int eventfd_async: 1;
340 unsigned int restricted: 1;
341 unsigned int off_timeout_used: 1;
342 unsigned int drain_active: 1;
343 } ____cacheline_aligned_in_smp;
345 /* submission data */
347 struct mutex uring_lock;
350 * Ring buffer of indices into array of io_uring_sqe, which is
351 * mmapped by the application using the IORING_OFF_SQES offset.
353 * This indirection could e.g. be used to assign fixed
354 * io_uring_sqe entries to operations and only submit them to
355 * the queue when needed.
357 * The kernel modifies neither the indices array nor the entries
361 struct io_uring_sqe *sq_sqes;
362 unsigned cached_sq_head;
364 struct list_head defer_list;
367 * Fixed resources fast path, should be accessed only under
368 * uring_lock, and updated through io_uring_register(2)
370 struct io_rsrc_node *rsrc_node;
371 struct io_file_table file_table;
372 unsigned nr_user_files;
373 unsigned nr_user_bufs;
374 struct io_mapped_ubuf **user_bufs;
376 struct io_submit_state submit_state;
377 struct list_head timeout_list;
378 struct list_head cq_overflow_list;
379 struct xarray io_buffers;
380 struct xarray personalities;
382 unsigned sq_thread_idle;
383 } ____cacheline_aligned_in_smp;
385 /* IRQ completion list, under ->completion_lock */
386 struct list_head locked_free_list;
387 unsigned int locked_free_nr;
389 const struct cred *sq_creds; /* cred used for __io_sq_thread() */
390 struct io_sq_data *sq_data; /* if using sq thread polling */
392 struct wait_queue_head sqo_sq_wait;
393 struct list_head sqd_list;
395 unsigned long check_cq_overflow;
398 unsigned cached_cq_tail;
400 struct eventfd_ctx *cq_ev_fd;
401 struct wait_queue_head poll_wait;
402 struct wait_queue_head cq_wait;
404 atomic_t cq_timeouts;
405 struct fasync_struct *cq_fasync;
406 unsigned cq_last_tm_flush;
407 } ____cacheline_aligned_in_smp;
410 spinlock_t completion_lock;
412 spinlock_t timeout_lock;
415 * ->iopoll_list is protected by the ctx->uring_lock for
416 * io_uring instances that don't use IORING_SETUP_SQPOLL.
417 * For SQPOLL, only the single threaded io_sq_thread() will
418 * manipulate the list, hence no extra locking is needed there.
420 struct list_head iopoll_list;
421 struct hlist_head *cancel_hash;
422 unsigned cancel_hash_bits;
423 bool poll_multi_queue;
424 } ____cacheline_aligned_in_smp;
426 struct io_restriction restrictions;
428 /* slow path rsrc auxilary data, used by update/register */
430 struct io_rsrc_node *rsrc_backup_node;
431 struct io_mapped_ubuf *dummy_ubuf;
432 struct io_rsrc_data *file_data;
433 struct io_rsrc_data *buf_data;
435 struct delayed_work rsrc_put_work;
436 struct llist_head rsrc_put_llist;
437 struct list_head rsrc_ref_list;
438 spinlock_t rsrc_ref_lock;
441 /* Keep this last, we don't need it for the fast path */
443 #if defined(CONFIG_UNIX)
444 struct socket *ring_sock;
446 /* hashed buffered write serialization */
447 struct io_wq_hash *hash_map;
449 /* Only used for accounting purposes */
450 struct user_struct *user;
451 struct mm_struct *mm_account;
453 /* ctx exit and cancelation */
454 struct llist_head fallback_llist;
455 struct delayed_work fallback_work;
456 struct work_struct exit_work;
457 struct list_head tctx_list;
458 struct completion ref_comp;
462 struct io_uring_task {
463 /* submission side */
466 struct wait_queue_head wait;
467 const struct io_ring_ctx *last;
469 struct percpu_counter inflight;
470 atomic_t inflight_tracked;
473 spinlock_t task_lock;
474 struct io_wq_work_list task_list;
475 struct callback_head task_work;
480 * First field must be the file pointer in all the
481 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
483 struct io_poll_iocb {
485 struct wait_queue_head *head;
489 struct wait_queue_entry wait;
492 struct io_poll_update {
498 bool update_user_data;
506 struct io_timeout_data {
507 struct io_kiocb *req;
508 struct hrtimer timer;
509 struct timespec64 ts;
510 enum hrtimer_mode mode;
515 struct sockaddr __user *addr;
516 int __user *addr_len;
518 unsigned long nofile;
538 struct list_head list;
539 /* head of the link, used by linked timeouts only */
540 struct io_kiocb *head;
541 /* for linked completions */
542 struct io_kiocb *prev;
545 struct io_timeout_rem {
550 struct timespec64 ts;
555 /* NOTE: kiocb has the file as the first member, so don't do it here */
563 struct sockaddr __user *addr;
570 struct compat_msghdr __user *umsg_compat;
571 struct user_msghdr __user *umsg;
577 struct io_buffer *kbuf;
583 struct filename *filename;
585 unsigned long nofile;
588 struct io_rsrc_update {
614 struct epoll_event event;
618 struct file *file_out;
619 struct file *file_in;
626 struct io_provide_buf {
640 const char __user *filename;
641 struct statx __user *buffer;
653 struct filename *oldpath;
654 struct filename *newpath;
662 struct filename *filename;
665 struct io_completion {
670 struct io_async_connect {
671 struct sockaddr_storage address;
674 struct io_async_msghdr {
675 struct iovec fast_iov[UIO_FASTIOV];
676 /* points to an allocated iov, if NULL we use fast_iov instead */
677 struct iovec *free_iov;
678 struct sockaddr __user *uaddr;
680 struct sockaddr_storage addr;
684 struct iovec fast_iov[UIO_FASTIOV];
685 const struct iovec *free_iovec;
686 struct iov_iter iter;
688 struct wait_page_queue wpq;
692 REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
693 REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
694 REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
695 REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
696 REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
697 REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
699 /* first byte is taken by user flags, shift it to not overlap */
704 REQ_F_LINK_TIMEOUT_BIT,
705 REQ_F_NEED_CLEANUP_BIT,
707 REQ_F_BUFFER_SELECTED_BIT,
708 REQ_F_COMPLETE_INLINE_BIT,
710 REQ_F_DONT_REISSUE_BIT,
713 REQ_F_ARM_LTIMEOUT_BIT,
714 /* keep async read/write and isreg together and in order */
715 REQ_F_NOWAIT_READ_BIT,
716 REQ_F_NOWAIT_WRITE_BIT,
719 /* not a real bit, just to check we're not overflowing the space */
725 REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
726 /* drain existing IO first */
727 REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
729 REQ_F_LINK = BIT(REQ_F_LINK_BIT),
730 /* doesn't sever on completion < 0 */
731 REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
733 REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
734 /* IOSQE_BUFFER_SELECT */
735 REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
737 /* fail rest of links */
738 REQ_F_FAIL = BIT(REQ_F_FAIL_BIT),
739 /* on inflight list, should be cancelled and waited on exit reliably */
740 REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
741 /* read/write uses file position */
742 REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
743 /* must not punt to workers */
744 REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
745 /* has or had linked timeout */
746 REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
748 REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
749 /* already went through poll handler */
750 REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
751 /* buffer already selected */
752 REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
753 /* completion is deferred through io_comp_state */
754 REQ_F_COMPLETE_INLINE = BIT(REQ_F_COMPLETE_INLINE_BIT),
755 /* caller should reissue async */
756 REQ_F_REISSUE = BIT(REQ_F_REISSUE_BIT),
757 /* don't attempt request reissue, see io_rw_reissue() */
758 REQ_F_DONT_REISSUE = BIT(REQ_F_DONT_REISSUE_BIT),
759 /* supports async reads */
760 REQ_F_NOWAIT_READ = BIT(REQ_F_NOWAIT_READ_BIT),
761 /* supports async writes */
762 REQ_F_NOWAIT_WRITE = BIT(REQ_F_NOWAIT_WRITE_BIT),
764 REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
765 /* has creds assigned */
766 REQ_F_CREDS = BIT(REQ_F_CREDS_BIT),
767 /* skip refcounting if not set */
768 REQ_F_REFCOUNT = BIT(REQ_F_REFCOUNT_BIT),
769 /* there is a linked timeout that has to be armed */
770 REQ_F_ARM_LTIMEOUT = BIT(REQ_F_ARM_LTIMEOUT_BIT),
774 struct io_poll_iocb poll;
775 struct io_poll_iocb *double_poll;
778 typedef void (*io_req_tw_func_t)(struct io_kiocb *req);
780 struct io_task_work {
782 struct io_wq_work_node node;
783 struct llist_node fallback_node;
785 io_req_tw_func_t func;
789 IORING_RSRC_FILE = 0,
790 IORING_RSRC_BUFFER = 1,
794 * NOTE! Each of the iocb union members has the file pointer
795 * as the first entry in their struct definition. So you can
796 * access the file pointer through any of the sub-structs,
797 * or directly as just 'ki_filp' in this struct.
803 struct io_poll_iocb poll;
804 struct io_poll_update poll_update;
805 struct io_accept accept;
807 struct io_cancel cancel;
808 struct io_timeout timeout;
809 struct io_timeout_rem timeout_rem;
810 struct io_connect connect;
811 struct io_sr_msg sr_msg;
813 struct io_close close;
814 struct io_rsrc_update rsrc_update;
815 struct io_fadvise fadvise;
816 struct io_madvise madvise;
817 struct io_epoll epoll;
818 struct io_splice splice;
819 struct io_provide_buf pbuf;
820 struct io_statx statx;
821 struct io_shutdown shutdown;
822 struct io_rename rename;
823 struct io_unlink unlink;
824 /* use only after cleaning per-op data, see io_clean_op() */
825 struct io_completion compl;
828 /* opcode allocated if it needs to store data for async defer */
831 /* polled IO has completed */
837 struct io_ring_ctx *ctx;
840 struct task_struct *task;
843 struct io_kiocb *link;
844 struct percpu_ref *fixed_rsrc_refs;
846 /* used with ctx->iopoll_list with reads/writes */
847 struct list_head inflight_entry;
848 struct io_task_work io_task_work;
849 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
850 struct hlist_node hash_node;
851 struct async_poll *apoll;
852 struct io_wq_work work;
853 const struct cred *creds;
855 /* store used ubuf, so we can prevent reloading */
856 struct io_mapped_ubuf *imu;
859 struct io_tctx_node {
860 struct list_head ctx_node;
861 struct task_struct *task;
862 struct io_ring_ctx *ctx;
865 struct io_defer_entry {
866 struct list_head list;
867 struct io_kiocb *req;
872 /* needs req->file assigned */
873 unsigned needs_file : 1;
874 /* hash wq insertion if file is a regular file */
875 unsigned hash_reg_file : 1;
876 /* unbound wq insertion if file is a non-regular file */
877 unsigned unbound_nonreg_file : 1;
878 /* opcode is not supported by this kernel */
879 unsigned not_supported : 1;
880 /* set if opcode supports polled "wait" */
882 unsigned pollout : 1;
883 /* op supports buffer selection */
884 unsigned buffer_select : 1;
885 /* do prep async if is going to be punted */
886 unsigned needs_async_setup : 1;
887 /* should block plug */
889 /* size of async data needed, if any */
890 unsigned short async_size;
893 static const struct io_op_def io_op_defs[] = {
894 [IORING_OP_NOP] = {},
895 [IORING_OP_READV] = {
897 .unbound_nonreg_file = 1,
900 .needs_async_setup = 1,
902 .async_size = sizeof(struct io_async_rw),
904 [IORING_OP_WRITEV] = {
907 .unbound_nonreg_file = 1,
909 .needs_async_setup = 1,
911 .async_size = sizeof(struct io_async_rw),
913 [IORING_OP_FSYNC] = {
916 [IORING_OP_READ_FIXED] = {
918 .unbound_nonreg_file = 1,
921 .async_size = sizeof(struct io_async_rw),
923 [IORING_OP_WRITE_FIXED] = {
926 .unbound_nonreg_file = 1,
929 .async_size = sizeof(struct io_async_rw),
931 [IORING_OP_POLL_ADD] = {
933 .unbound_nonreg_file = 1,
935 [IORING_OP_POLL_REMOVE] = {},
936 [IORING_OP_SYNC_FILE_RANGE] = {
939 [IORING_OP_SENDMSG] = {
941 .unbound_nonreg_file = 1,
943 .needs_async_setup = 1,
944 .async_size = sizeof(struct io_async_msghdr),
946 [IORING_OP_RECVMSG] = {
948 .unbound_nonreg_file = 1,
951 .needs_async_setup = 1,
952 .async_size = sizeof(struct io_async_msghdr),
954 [IORING_OP_TIMEOUT] = {
955 .async_size = sizeof(struct io_timeout_data),
957 [IORING_OP_TIMEOUT_REMOVE] = {
958 /* used by timeout updates' prep() */
960 [IORING_OP_ACCEPT] = {
962 .unbound_nonreg_file = 1,
965 [IORING_OP_ASYNC_CANCEL] = {},
966 [IORING_OP_LINK_TIMEOUT] = {
967 .async_size = sizeof(struct io_timeout_data),
969 [IORING_OP_CONNECT] = {
971 .unbound_nonreg_file = 1,
973 .needs_async_setup = 1,
974 .async_size = sizeof(struct io_async_connect),
976 [IORING_OP_FALLOCATE] = {
979 [IORING_OP_OPENAT] = {},
980 [IORING_OP_CLOSE] = {},
981 [IORING_OP_FILES_UPDATE] = {},
982 [IORING_OP_STATX] = {},
985 .unbound_nonreg_file = 1,
989 .async_size = sizeof(struct io_async_rw),
991 [IORING_OP_WRITE] = {
993 .unbound_nonreg_file = 1,
996 .async_size = sizeof(struct io_async_rw),
998 [IORING_OP_FADVISE] = {
1001 [IORING_OP_MADVISE] = {},
1002 [IORING_OP_SEND] = {
1004 .unbound_nonreg_file = 1,
1007 [IORING_OP_RECV] = {
1009 .unbound_nonreg_file = 1,
1013 [IORING_OP_OPENAT2] = {
1015 [IORING_OP_EPOLL_CTL] = {
1016 .unbound_nonreg_file = 1,
1018 [IORING_OP_SPLICE] = {
1021 .unbound_nonreg_file = 1,
1023 [IORING_OP_PROVIDE_BUFFERS] = {},
1024 [IORING_OP_REMOVE_BUFFERS] = {},
1028 .unbound_nonreg_file = 1,
1030 [IORING_OP_SHUTDOWN] = {
1033 [IORING_OP_RENAMEAT] = {},
1034 [IORING_OP_UNLINKAT] = {},
1037 /* requests with any of those set should undergo io_disarm_next() */
1038 #define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
1040 static bool io_disarm_next(struct io_kiocb *req);
1041 static void io_uring_del_tctx_node(unsigned long index);
1042 static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
1043 struct task_struct *task,
1045 static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
1047 static bool io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
1048 long res, unsigned int cflags);
1049 static void io_put_req(struct io_kiocb *req);
1050 static void io_put_req_deferred(struct io_kiocb *req);
1051 static void io_dismantle_req(struct io_kiocb *req);
1052 static void io_queue_linked_timeout(struct io_kiocb *req);
1053 static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
1054 struct io_uring_rsrc_update2 *up,
1056 static void io_clean_op(struct io_kiocb *req);
1057 static struct file *io_file_get(struct io_ring_ctx *ctx,
1058 struct io_kiocb *req, int fd, bool fixed);
1059 static void __io_queue_sqe(struct io_kiocb *req);
1060 static void io_rsrc_put_work(struct work_struct *work);
1062 static void io_req_task_queue(struct io_kiocb *req);
1063 static void io_submit_flush_completions(struct io_ring_ctx *ctx);
1064 static int io_req_prep_async(struct io_kiocb *req);
1066 static struct kmem_cache *req_cachep;
1068 static const struct file_operations io_uring_fops;
1070 struct sock *io_uring_get_socket(struct file *file)
1072 #if defined(CONFIG_UNIX)
1073 if (file->f_op == &io_uring_fops) {
1074 struct io_ring_ctx *ctx = file->private_data;
1076 return ctx->ring_sock->sk;
1081 EXPORT_SYMBOL(io_uring_get_socket);
1083 #define io_for_each_link(pos, head) \
1084 for (pos = (head); pos; pos = pos->link)
1087 * Shamelessly stolen from the mm implementation of page reference checking,
1088 * see commit f958d7b528b1 for details.
1090 #define req_ref_zero_or_close_to_overflow(req) \
1091 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1093 static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
1095 WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
1096 return atomic_inc_not_zero(&req->refs);
1099 static inline bool req_ref_put_and_test(struct io_kiocb *req)
1101 if (likely(!(req->flags & REQ_F_REFCOUNT)))
1104 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1105 return atomic_dec_and_test(&req->refs);
1108 static inline void req_ref_put(struct io_kiocb *req)
1110 WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
1111 WARN_ON_ONCE(req_ref_put_and_test(req));
1114 static inline void req_ref_get(struct io_kiocb *req)
1116 WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
1117 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1118 atomic_inc(&req->refs);
1121 static inline void __io_req_set_refcount(struct io_kiocb *req, int nr)
1123 if (!(req->flags & REQ_F_REFCOUNT)) {
1124 req->flags |= REQ_F_REFCOUNT;
1125 atomic_set(&req->refs, nr);
1129 static inline void io_req_set_refcount(struct io_kiocb *req)
1131 __io_req_set_refcount(req, 1);
1134 static inline void io_req_set_rsrc_node(struct io_kiocb *req)
1136 struct io_ring_ctx *ctx = req->ctx;
1138 if (!req->fixed_rsrc_refs) {
1139 req->fixed_rsrc_refs = &ctx->rsrc_node->refs;
1140 percpu_ref_get(req->fixed_rsrc_refs);
1144 static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl)
1146 bool got = percpu_ref_tryget(ref);
1148 /* already at zero, wait for ->release() */
1150 wait_for_completion(compl);
1151 percpu_ref_resurrect(ref);
1153 percpu_ref_put(ref);
1156 static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
1159 struct io_kiocb *req;
1161 if (task && head->task != task)
1166 io_for_each_link(req, head) {
1167 if (req->flags & REQ_F_INFLIGHT)
1173 static inline void req_set_fail(struct io_kiocb *req)
1175 req->flags |= REQ_F_FAIL;
1178 static void io_ring_ctx_ref_free(struct percpu_ref *ref)
1180 struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
1182 complete(&ctx->ref_comp);
1185 static inline bool io_is_timeout_noseq(struct io_kiocb *req)
1187 return !req->timeout.off;
1190 static void io_fallback_req_func(struct work_struct *work)
1192 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
1193 fallback_work.work);
1194 struct llist_node *node = llist_del_all(&ctx->fallback_llist);
1195 struct io_kiocb *req, *tmp;
1197 percpu_ref_get(&ctx->refs);
1198 llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node)
1199 req->io_task_work.func(req);
1200 percpu_ref_put(&ctx->refs);
1203 static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
1205 struct io_ring_ctx *ctx;
1208 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1213 * Use 5 bits less than the max cq entries, that should give us around
1214 * 32 entries per hash list if totally full and uniformly spread.
1216 hash_bits = ilog2(p->cq_entries);
1220 ctx->cancel_hash_bits = hash_bits;
1221 ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
1223 if (!ctx->cancel_hash)
1225 __hash_init(ctx->cancel_hash, 1U << hash_bits);
1227 ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL);
1228 if (!ctx->dummy_ubuf)
1230 /* set invalid range, so io_import_fixed() fails meeting it */
1231 ctx->dummy_ubuf->ubuf = -1UL;
1233 if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
1234 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
1237 ctx->flags = p->flags;
1238 init_waitqueue_head(&ctx->sqo_sq_wait);
1239 INIT_LIST_HEAD(&ctx->sqd_list);
1240 init_waitqueue_head(&ctx->poll_wait);
1241 INIT_LIST_HEAD(&ctx->cq_overflow_list);
1242 init_completion(&ctx->ref_comp);
1243 xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
1244 xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
1245 mutex_init(&ctx->uring_lock);
1246 init_waitqueue_head(&ctx->cq_wait);
1247 spin_lock_init(&ctx->completion_lock);
1248 spin_lock_init(&ctx->timeout_lock);
1249 INIT_LIST_HEAD(&ctx->iopoll_list);
1250 INIT_LIST_HEAD(&ctx->defer_list);
1251 INIT_LIST_HEAD(&ctx->timeout_list);
1252 spin_lock_init(&ctx->rsrc_ref_lock);
1253 INIT_LIST_HEAD(&ctx->rsrc_ref_list);
1254 INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
1255 init_llist_head(&ctx->rsrc_put_llist);
1256 INIT_LIST_HEAD(&ctx->tctx_list);
1257 INIT_LIST_HEAD(&ctx->submit_state.free_list);
1258 INIT_LIST_HEAD(&ctx->locked_free_list);
1259 INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func);
1262 kfree(ctx->dummy_ubuf);
1263 kfree(ctx->cancel_hash);
1268 static void io_account_cq_overflow(struct io_ring_ctx *ctx)
1270 struct io_rings *r = ctx->rings;
1272 WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1);
1276 static bool req_need_defer(struct io_kiocb *req, u32 seq)
1278 if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
1279 struct io_ring_ctx *ctx = req->ctx;
1281 return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail;
1287 #define FFS_ASYNC_READ 0x1UL
1288 #define FFS_ASYNC_WRITE 0x2UL
1290 #define FFS_ISREG 0x4UL
1292 #define FFS_ISREG 0x0UL
1294 #define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
1296 static inline bool io_req_ffs_set(struct io_kiocb *req)
1298 return IS_ENABLED(CONFIG_64BIT) && (req->flags & REQ_F_FIXED_FILE);
1301 static void io_req_track_inflight(struct io_kiocb *req)
1303 if (!(req->flags & REQ_F_INFLIGHT)) {
1304 req->flags |= REQ_F_INFLIGHT;
1305 atomic_inc(¤t->io_uring->inflight_tracked);
1309 static inline void io_unprep_linked_timeout(struct io_kiocb *req)
1311 req->flags &= ~REQ_F_LINK_TIMEOUT;
1314 static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req)
1316 if (WARN_ON_ONCE(!req->link))
1319 req->flags &= ~REQ_F_ARM_LTIMEOUT;
1320 req->flags |= REQ_F_LINK_TIMEOUT;
1322 /* linked timeouts should have two refs once prep'ed */
1323 io_req_set_refcount(req);
1324 __io_req_set_refcount(req->link, 2);
1328 static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
1330 if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT)))
1332 return __io_prep_linked_timeout(req);
1335 static void io_prep_async_work(struct io_kiocb *req)
1337 const struct io_op_def *def = &io_op_defs[req->opcode];
1338 struct io_ring_ctx *ctx = req->ctx;
1340 if (!(req->flags & REQ_F_CREDS)) {
1341 req->flags |= REQ_F_CREDS;
1342 req->creds = get_current_cred();
1345 req->work.list.next = NULL;
1346 req->work.flags = 0;
1347 if (req->flags & REQ_F_FORCE_ASYNC)
1348 req->work.flags |= IO_WQ_WORK_CONCURRENT;
1350 if (req->flags & REQ_F_ISREG) {
1351 if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
1352 io_wq_hash_work(&req->work, file_inode(req->file));
1353 } else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
1354 if (def->unbound_nonreg_file)
1355 req->work.flags |= IO_WQ_WORK_UNBOUND;
1358 switch (req->opcode) {
1359 case IORING_OP_SPLICE:
1361 if (!S_ISREG(file_inode(req->splice.file_in)->i_mode))
1362 req->work.flags |= IO_WQ_WORK_UNBOUND;
1367 static void io_prep_async_link(struct io_kiocb *req)
1369 struct io_kiocb *cur;
1371 if (req->flags & REQ_F_LINK_TIMEOUT) {
1372 struct io_ring_ctx *ctx = req->ctx;
1374 spin_lock(&ctx->completion_lock);
1375 io_for_each_link(cur, req)
1376 io_prep_async_work(cur);
1377 spin_unlock(&ctx->completion_lock);
1379 io_for_each_link(cur, req)
1380 io_prep_async_work(cur);
1384 static void io_queue_async_work(struct io_kiocb *req)
1386 struct io_ring_ctx *ctx = req->ctx;
1387 struct io_kiocb *link = io_prep_linked_timeout(req);
1388 struct io_uring_task *tctx = req->task->io_uring;
1391 BUG_ON(!tctx->io_wq);
1393 /* init ->work of the whole link before punting */
1394 io_prep_async_link(req);
1397 * Not expected to happen, but if we do have a bug where this _can_
1398 * happen, catch it here and ensure the request is marked as
1399 * canceled. That will make io-wq go through the usual work cancel
1400 * procedure rather than attempt to run this request (or create a new
1403 if (WARN_ON_ONCE(!same_thread_group(req->task, current)))
1404 req->work.flags |= IO_WQ_WORK_CANCEL;
1406 trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
1407 &req->work, req->flags);
1408 io_wq_enqueue(tctx->io_wq, &req->work);
1410 io_queue_linked_timeout(link);
1413 static void io_kill_timeout(struct io_kiocb *req, int status)
1414 __must_hold(&req->ctx->completion_lock)
1415 __must_hold(&req->ctx->timeout_lock)
1417 struct io_timeout_data *io = req->async_data;
1419 if (hrtimer_try_to_cancel(&io->timer) != -1) {
1420 atomic_set(&req->ctx->cq_timeouts,
1421 atomic_read(&req->ctx->cq_timeouts) + 1);
1422 list_del_init(&req->timeout.list);
1423 io_cqring_fill_event(req->ctx, req->user_data, status, 0);
1424 io_put_req_deferred(req);
1428 static void io_queue_deferred(struct io_ring_ctx *ctx)
1430 while (!list_empty(&ctx->defer_list)) {
1431 struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
1432 struct io_defer_entry, list);
1434 if (req_need_defer(de->req, de->seq))
1436 list_del_init(&de->list);
1437 io_req_task_queue(de->req);
1442 static void io_flush_timeouts(struct io_ring_ctx *ctx)
1443 __must_hold(&ctx->completion_lock)
1445 u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
1447 spin_lock_irq(&ctx->timeout_lock);
1448 while (!list_empty(&ctx->timeout_list)) {
1449 u32 events_needed, events_got;
1450 struct io_kiocb *req = list_first_entry(&ctx->timeout_list,
1451 struct io_kiocb, timeout.list);
1453 if (io_is_timeout_noseq(req))
1457 * Since seq can easily wrap around over time, subtract
1458 * the last seq at which timeouts were flushed before comparing.
1459 * Assuming not more than 2^31-1 events have happened since,
1460 * these subtractions won't have wrapped, so we can check if
1461 * target is in [last_seq, current_seq] by comparing the two.
1463 events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
1464 events_got = seq - ctx->cq_last_tm_flush;
1465 if (events_got < events_needed)
1468 list_del_init(&req->timeout.list);
1469 io_kill_timeout(req, 0);
1471 ctx->cq_last_tm_flush = seq;
1472 spin_unlock_irq(&ctx->timeout_lock);
1475 static void __io_commit_cqring_flush(struct io_ring_ctx *ctx)
1477 if (ctx->off_timeout_used)
1478 io_flush_timeouts(ctx);
1479 if (ctx->drain_active)
1480 io_queue_deferred(ctx);
1483 static inline void io_commit_cqring(struct io_ring_ctx *ctx)
1485 if (unlikely(ctx->off_timeout_used || ctx->drain_active))
1486 __io_commit_cqring_flush(ctx);
1487 /* order cqe stores with ring update */
1488 smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
1491 static inline bool io_sqring_full(struct io_ring_ctx *ctx)
1493 struct io_rings *r = ctx->rings;
1495 return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
1498 static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
1500 return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
1503 static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx)
1505 struct io_rings *rings = ctx->rings;
1506 unsigned tail, mask = ctx->cq_entries - 1;
1509 * writes to the cq entry need to come after reading head; the
1510 * control dependency is enough as we're using WRITE_ONCE to
1513 if (__io_cqring_events(ctx) == ctx->cq_entries)
1516 tail = ctx->cached_cq_tail++;
1517 return &rings->cqes[tail & mask];
1520 static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
1522 if (likely(!ctx->cq_ev_fd))
1524 if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
1526 return !ctx->eventfd_async || io_wq_current_is_worker();
1529 static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
1532 * wake_up_all() may seem excessive, but io_wake_function() and
1533 * io_should_wake() handle the termination of the loop and only
1534 * wake as many waiters as we need to.
1536 if (wq_has_sleeper(&ctx->cq_wait))
1537 wake_up_all(&ctx->cq_wait);
1538 if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
1539 wake_up(&ctx->sq_data->wait);
1540 if (io_should_trigger_evfd(ctx))
1541 eventfd_signal(ctx->cq_ev_fd, 1);
1542 if (waitqueue_active(&ctx->poll_wait)) {
1543 wake_up_interruptible(&ctx->poll_wait);
1544 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
1548 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
1550 if (ctx->flags & IORING_SETUP_SQPOLL) {
1551 if (wq_has_sleeper(&ctx->cq_wait))
1552 wake_up_all(&ctx->cq_wait);
1554 if (io_should_trigger_evfd(ctx))
1555 eventfd_signal(ctx->cq_ev_fd, 1);
1556 if (waitqueue_active(&ctx->poll_wait)) {
1557 wake_up_interruptible(&ctx->poll_wait);
1558 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
1562 /* Returns true if there are no backlogged entries after the flush */
1563 static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
1565 bool all_flushed, posted;
1567 if (!force && __io_cqring_events(ctx) == ctx->cq_entries)
1571 spin_lock(&ctx->completion_lock);
1572 while (!list_empty(&ctx->cq_overflow_list)) {
1573 struct io_uring_cqe *cqe = io_get_cqe(ctx);
1574 struct io_overflow_cqe *ocqe;
1578 ocqe = list_first_entry(&ctx->cq_overflow_list,
1579 struct io_overflow_cqe, list);
1581 memcpy(cqe, &ocqe->cqe, sizeof(*cqe));
1583 io_account_cq_overflow(ctx);
1586 list_del(&ocqe->list);
1590 all_flushed = list_empty(&ctx->cq_overflow_list);
1592 clear_bit(0, &ctx->check_cq_overflow);
1593 WRITE_ONCE(ctx->rings->sq_flags,
1594 ctx->rings->sq_flags & ~IORING_SQ_CQ_OVERFLOW);
1598 io_commit_cqring(ctx);
1599 spin_unlock(&ctx->completion_lock);
1601 io_cqring_ev_posted(ctx);
1605 static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx)
1609 if (test_bit(0, &ctx->check_cq_overflow)) {
1610 /* iopoll syncs against uring_lock, not completion_lock */
1611 if (ctx->flags & IORING_SETUP_IOPOLL)
1612 mutex_lock(&ctx->uring_lock);
1613 ret = __io_cqring_overflow_flush(ctx, false);
1614 if (ctx->flags & IORING_SETUP_IOPOLL)
1615 mutex_unlock(&ctx->uring_lock);
1621 /* must to be called somewhat shortly after putting a request */
1622 static inline void io_put_task(struct task_struct *task, int nr)
1624 struct io_uring_task *tctx = task->io_uring;
1626 percpu_counter_sub(&tctx->inflight, nr);
1627 if (unlikely(atomic_read(&tctx->in_idle)))
1628 wake_up(&tctx->wait);
1629 put_task_struct_many(task, nr);
1632 static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data,
1633 long res, unsigned int cflags)
1635 struct io_overflow_cqe *ocqe;
1637 ocqe = kmalloc(sizeof(*ocqe), GFP_ATOMIC | __GFP_ACCOUNT);
1640 * If we're in ring overflow flush mode, or in task cancel mode,
1641 * or cannot allocate an overflow entry, then we need to drop it
1644 io_account_cq_overflow(ctx);
1647 if (list_empty(&ctx->cq_overflow_list)) {
1648 set_bit(0, &ctx->check_cq_overflow);
1649 WRITE_ONCE(ctx->rings->sq_flags,
1650 ctx->rings->sq_flags | IORING_SQ_CQ_OVERFLOW);
1653 ocqe->cqe.user_data = user_data;
1654 ocqe->cqe.res = res;
1655 ocqe->cqe.flags = cflags;
1656 list_add_tail(&ocqe->list, &ctx->cq_overflow_list);
1660 static inline bool __io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
1661 long res, unsigned int cflags)
1663 struct io_uring_cqe *cqe;
1665 trace_io_uring_complete(ctx, user_data, res, cflags);
1668 * If we can't get a cq entry, userspace overflowed the
1669 * submission (by quite a lot). Increment the overflow count in
1672 cqe = io_get_cqe(ctx);
1674 WRITE_ONCE(cqe->user_data, user_data);
1675 WRITE_ONCE(cqe->res, res);
1676 WRITE_ONCE(cqe->flags, cflags);
1679 return io_cqring_event_overflow(ctx, user_data, res, cflags);
1682 /* not as hot to bloat with inlining */
1683 static noinline bool io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
1684 long res, unsigned int cflags)
1686 return __io_cqring_fill_event(ctx, user_data, res, cflags);
1689 static void io_req_complete_post(struct io_kiocb *req, long res,
1690 unsigned int cflags)
1692 struct io_ring_ctx *ctx = req->ctx;
1694 spin_lock(&ctx->completion_lock);
1695 __io_cqring_fill_event(ctx, req->user_data, res, cflags);
1697 * If we're the last reference to this request, add to our locked
1700 if (req_ref_put_and_test(req)) {
1701 if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
1702 if (req->flags & IO_DISARM_MASK)
1703 io_disarm_next(req);
1705 io_req_task_queue(req->link);
1709 io_dismantle_req(req);
1710 io_put_task(req->task, 1);
1711 list_add(&req->inflight_entry, &ctx->locked_free_list);
1712 ctx->locked_free_nr++;
1714 if (!percpu_ref_tryget(&ctx->refs))
1717 io_commit_cqring(ctx);
1718 spin_unlock(&ctx->completion_lock);
1721 io_cqring_ev_posted(ctx);
1722 percpu_ref_put(&ctx->refs);
1726 static inline bool io_req_needs_clean(struct io_kiocb *req)
1728 return req->flags & IO_REQ_CLEAN_FLAGS;
1731 static void io_req_complete_state(struct io_kiocb *req, long res,
1732 unsigned int cflags)
1734 if (io_req_needs_clean(req))
1737 req->compl.cflags = cflags;
1738 req->flags |= REQ_F_COMPLETE_INLINE;
1741 static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
1742 long res, unsigned cflags)
1744 if (issue_flags & IO_URING_F_COMPLETE_DEFER)
1745 io_req_complete_state(req, res, cflags);
1747 io_req_complete_post(req, res, cflags);
1750 static inline void io_req_complete(struct io_kiocb *req, long res)
1752 __io_req_complete(req, 0, res, 0);
1755 static void io_req_complete_failed(struct io_kiocb *req, long res)
1758 io_req_complete_post(req, res, 0);
1762 * Don't initialise the fields below on every allocation, but do that in
1763 * advance and keep them valid across allocations.
1765 static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx)
1769 req->async_data = NULL;
1770 /* not necessary, but safer to zero */
1774 static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx,
1775 struct io_submit_state *state)
1777 spin_lock(&ctx->completion_lock);
1778 list_splice_init(&ctx->locked_free_list, &state->free_list);
1779 ctx->locked_free_nr = 0;
1780 spin_unlock(&ctx->completion_lock);
1783 /* Returns true IFF there are requests in the cache */
1784 static bool io_flush_cached_reqs(struct io_ring_ctx *ctx)
1786 struct io_submit_state *state = &ctx->submit_state;
1790 * If we have more than a batch's worth of requests in our IRQ side
1791 * locked cache, grab the lock and move them over to our submission
1794 if (READ_ONCE(ctx->locked_free_nr) > IO_COMPL_BATCH)
1795 io_flush_cached_locked_reqs(ctx, state);
1797 nr = state->free_reqs;
1798 while (!list_empty(&state->free_list)) {
1799 struct io_kiocb *req = list_first_entry(&state->free_list,
1800 struct io_kiocb, inflight_entry);
1802 list_del(&req->inflight_entry);
1803 state->reqs[nr++] = req;
1804 if (nr == ARRAY_SIZE(state->reqs))
1808 state->free_reqs = nr;
1813 * A request might get retired back into the request caches even before opcode
1814 * handlers and io_issue_sqe() are done with it, e.g. inline completion path.
1815 * Because of that, io_alloc_req() should be called only under ->uring_lock
1816 * and with extra caution to not get a request that is still worked on.
1818 static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
1819 __must_hold(&ctx->uring_lock)
1821 struct io_submit_state *state = &ctx->submit_state;
1822 gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
1825 BUILD_BUG_ON(ARRAY_SIZE(state->reqs) < IO_REQ_ALLOC_BATCH);
1827 if (likely(state->free_reqs || io_flush_cached_reqs(ctx)))
1830 ret = kmem_cache_alloc_bulk(req_cachep, gfp, IO_REQ_ALLOC_BATCH,
1834 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1835 * retry single alloc to be on the safe side.
1837 if (unlikely(ret <= 0)) {
1838 state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
1839 if (!state->reqs[0])
1844 for (i = 0; i < ret; i++)
1845 io_preinit_req(state->reqs[i], ctx);
1846 state->free_reqs = ret;
1849 return state->reqs[state->free_reqs];
1852 static inline void io_put_file(struct file *file)
1858 static void io_dismantle_req(struct io_kiocb *req)
1860 unsigned int flags = req->flags;
1862 if (io_req_needs_clean(req))
1864 if (!(flags & REQ_F_FIXED_FILE))
1865 io_put_file(req->file);
1866 if (req->fixed_rsrc_refs)
1867 percpu_ref_put(req->fixed_rsrc_refs);
1868 if (req->async_data) {
1869 kfree(req->async_data);
1870 req->async_data = NULL;
1874 static void __io_free_req(struct io_kiocb *req)
1876 struct io_ring_ctx *ctx = req->ctx;
1878 io_dismantle_req(req);
1879 io_put_task(req->task, 1);
1881 spin_lock(&ctx->completion_lock);
1882 list_add(&req->inflight_entry, &ctx->locked_free_list);
1883 ctx->locked_free_nr++;
1884 spin_unlock(&ctx->completion_lock);
1886 percpu_ref_put(&ctx->refs);
1889 static inline void io_remove_next_linked(struct io_kiocb *req)
1891 struct io_kiocb *nxt = req->link;
1893 req->link = nxt->link;
1897 static bool io_kill_linked_timeout(struct io_kiocb *req)
1898 __must_hold(&req->ctx->completion_lock)
1899 __must_hold(&req->ctx->timeout_lock)
1901 struct io_kiocb *link = req->link;
1903 if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
1904 struct io_timeout_data *io = link->async_data;
1906 io_remove_next_linked(req);
1907 link->timeout.head = NULL;
1908 if (hrtimer_try_to_cancel(&io->timer) != -1) {
1909 io_cqring_fill_event(link->ctx, link->user_data,
1911 io_put_req_deferred(link);
1918 static void io_fail_links(struct io_kiocb *req)
1919 __must_hold(&req->ctx->completion_lock)
1921 struct io_kiocb *nxt, *link = req->link;
1928 trace_io_uring_fail_link(req, link);
1929 io_cqring_fill_event(link->ctx, link->user_data, -ECANCELED, 0);
1930 io_put_req_deferred(link);
1935 static bool io_disarm_next(struct io_kiocb *req)
1936 __must_hold(&req->ctx->completion_lock)
1938 bool posted = false;
1940 if (req->flags & REQ_F_ARM_LTIMEOUT) {
1941 struct io_kiocb *link = req->link;
1943 req->flags &= ~REQ_F_ARM_LTIMEOUT;
1944 if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
1945 io_remove_next_linked(req);
1946 io_cqring_fill_event(link->ctx, link->user_data,
1948 io_put_req_deferred(link);
1951 } else if (req->flags & REQ_F_LINK_TIMEOUT) {
1952 struct io_ring_ctx *ctx = req->ctx;
1954 spin_lock_irq(&ctx->timeout_lock);
1955 posted = io_kill_linked_timeout(req);
1956 spin_unlock_irq(&ctx->timeout_lock);
1958 if (unlikely((req->flags & REQ_F_FAIL) &&
1959 !(req->flags & REQ_F_HARDLINK))) {
1960 posted |= (req->link != NULL);
1966 static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
1968 struct io_kiocb *nxt;
1971 * If LINK is set, we have dependent requests in this chain. If we
1972 * didn't fail this request, queue the first one up, moving any other
1973 * dependencies to the next request. In case of failure, fail the rest
1976 if (req->flags & IO_DISARM_MASK) {
1977 struct io_ring_ctx *ctx = req->ctx;
1980 spin_lock(&ctx->completion_lock);
1981 posted = io_disarm_next(req);
1983 io_commit_cqring(req->ctx);
1984 spin_unlock(&ctx->completion_lock);
1986 io_cqring_ev_posted(ctx);
1993 static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
1995 if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK))))
1997 return __io_req_find_next(req);
2000 static void ctx_flush_and_put(struct io_ring_ctx *ctx)
2004 if (ctx->submit_state.compl_nr) {
2005 mutex_lock(&ctx->uring_lock);
2006 io_submit_flush_completions(ctx);
2007 mutex_unlock(&ctx->uring_lock);
2009 percpu_ref_put(&ctx->refs);
2012 static void tctx_task_work(struct callback_head *cb)
2014 struct io_ring_ctx *ctx = NULL;
2015 struct io_uring_task *tctx = container_of(cb, struct io_uring_task,
2019 struct io_wq_work_node *node;
2021 spin_lock_irq(&tctx->task_lock);
2022 node = tctx->task_list.first;
2023 INIT_WQ_LIST(&tctx->task_list);
2025 tctx->task_running = false;
2026 spin_unlock_irq(&tctx->task_lock);
2031 struct io_wq_work_node *next = node->next;
2032 struct io_kiocb *req = container_of(node, struct io_kiocb,
2035 if (req->ctx != ctx) {
2036 ctx_flush_and_put(ctx);
2038 percpu_ref_get(&ctx->refs);
2040 req->io_task_work.func(req);
2047 ctx_flush_and_put(ctx);
2050 static void io_req_task_work_add(struct io_kiocb *req)
2052 struct task_struct *tsk = req->task;
2053 struct io_uring_task *tctx = tsk->io_uring;
2054 enum task_work_notify_mode notify;
2055 struct io_wq_work_node *node;
2056 unsigned long flags;
2059 WARN_ON_ONCE(!tctx);
2061 spin_lock_irqsave(&tctx->task_lock, flags);
2062 wq_list_add_tail(&req->io_task_work.node, &tctx->task_list);
2063 running = tctx->task_running;
2065 tctx->task_running = true;
2066 spin_unlock_irqrestore(&tctx->task_lock, flags);
2068 /* task_work already pending, we're done */
2073 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2074 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2075 * processing task_work. There's no reliable way to tell if TWA_RESUME
2078 notify = (req->ctx->flags & IORING_SETUP_SQPOLL) ? TWA_NONE : TWA_SIGNAL;
2079 if (!task_work_add(tsk, &tctx->task_work, notify)) {
2080 wake_up_process(tsk);
2084 spin_lock_irqsave(&tctx->task_lock, flags);
2085 tctx->task_running = false;
2086 node = tctx->task_list.first;
2087 INIT_WQ_LIST(&tctx->task_list);
2088 spin_unlock_irqrestore(&tctx->task_lock, flags);
2091 req = container_of(node, struct io_kiocb, io_task_work.node);
2093 if (llist_add(&req->io_task_work.fallback_node,
2094 &req->ctx->fallback_llist))
2095 schedule_delayed_work(&req->ctx->fallback_work, 1);
2099 static void io_req_task_cancel(struct io_kiocb *req)
2101 struct io_ring_ctx *ctx = req->ctx;
2103 /* ctx is guaranteed to stay alive while we hold uring_lock */
2104 mutex_lock(&ctx->uring_lock);
2105 io_req_complete_failed(req, req->result);
2106 mutex_unlock(&ctx->uring_lock);
2109 static void io_req_task_submit(struct io_kiocb *req)
2111 struct io_ring_ctx *ctx = req->ctx;
2113 /* ctx stays valid until unlock, even if we drop all ours ctx->refs */
2114 mutex_lock(&ctx->uring_lock);
2115 if (likely(!(req->task->flags & PF_EXITING)))
2116 __io_queue_sqe(req);
2118 io_req_complete_failed(req, -EFAULT);
2119 mutex_unlock(&ctx->uring_lock);
2122 static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
2125 req->io_task_work.func = io_req_task_cancel;
2126 io_req_task_work_add(req);
2129 static void io_req_task_queue(struct io_kiocb *req)
2131 req->io_task_work.func = io_req_task_submit;
2132 io_req_task_work_add(req);
2135 static void io_req_task_queue_reissue(struct io_kiocb *req)
2137 req->io_task_work.func = io_queue_async_work;
2138 io_req_task_work_add(req);
2141 static inline void io_queue_next(struct io_kiocb *req)
2143 struct io_kiocb *nxt = io_req_find_next(req);
2146 io_req_task_queue(nxt);
2149 static void io_free_req(struct io_kiocb *req)
2156 struct task_struct *task;
2161 static inline void io_init_req_batch(struct req_batch *rb)
2168 static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
2169 struct req_batch *rb)
2172 percpu_ref_put_many(&ctx->refs, rb->ctx_refs);
2173 if (rb->task == current)
2174 current->io_uring->cached_refs += rb->task_refs;
2176 io_put_task(rb->task, rb->task_refs);
2179 static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req,
2180 struct io_submit_state *state)
2183 io_dismantle_req(req);
2185 if (req->task != rb->task) {
2187 io_put_task(rb->task, rb->task_refs);
2188 rb->task = req->task;
2194 if (state->free_reqs != ARRAY_SIZE(state->reqs))
2195 state->reqs[state->free_reqs++] = req;
2197 list_add(&req->inflight_entry, &state->free_list);
2200 static void io_submit_flush_completions(struct io_ring_ctx *ctx)
2201 __must_hold(&ctx->uring_lock)
2203 struct io_submit_state *state = &ctx->submit_state;
2204 int i, nr = state->compl_nr;
2205 struct req_batch rb;
2207 spin_lock(&ctx->completion_lock);
2208 for (i = 0; i < nr; i++) {
2209 struct io_kiocb *req = state->compl_reqs[i];
2211 __io_cqring_fill_event(ctx, req->user_data, req->result,
2214 io_commit_cqring(ctx);
2215 spin_unlock(&ctx->completion_lock);
2216 io_cqring_ev_posted(ctx);
2218 io_init_req_batch(&rb);
2219 for (i = 0; i < nr; i++) {
2220 struct io_kiocb *req = state->compl_reqs[i];
2222 if (req_ref_put_and_test(req))
2223 io_req_free_batch(&rb, req, &ctx->submit_state);
2226 io_req_free_batch_finish(ctx, &rb);
2227 state->compl_nr = 0;
2231 * Drop reference to request, return next in chain (if there is one) if this
2232 * was the last reference to this request.
2234 static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
2236 struct io_kiocb *nxt = NULL;
2238 if (req_ref_put_and_test(req)) {
2239 nxt = io_req_find_next(req);
2245 static inline void io_put_req(struct io_kiocb *req)
2247 if (req_ref_put_and_test(req))
2251 static inline void io_put_req_deferred(struct io_kiocb *req)
2253 if (req_ref_put_and_test(req)) {
2254 req->io_task_work.func = io_free_req;
2255 io_req_task_work_add(req);
2259 static unsigned io_cqring_events(struct io_ring_ctx *ctx)
2261 /* See comment at the top of this file */
2263 return __io_cqring_events(ctx);
2266 static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
2268 struct io_rings *rings = ctx->rings;
2270 /* make sure SQ entry isn't read before tail */
2271 return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
2274 static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
2276 unsigned int cflags;
2278 cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
2279 cflags |= IORING_CQE_F_BUFFER;
2280 req->flags &= ~REQ_F_BUFFER_SELECTED;
2285 static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
2287 struct io_buffer *kbuf;
2289 if (likely(!(req->flags & REQ_F_BUFFER_SELECTED)))
2291 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
2292 return io_put_kbuf(req, kbuf);
2295 static inline bool io_run_task_work(void)
2297 if (test_thread_flag(TIF_NOTIFY_SIGNAL) || current->task_works) {
2298 __set_current_state(TASK_RUNNING);
2299 tracehook_notify_signal();
2307 * Find and free completed poll iocbs
2309 static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
2310 struct list_head *done)
2312 struct req_batch rb;
2313 struct io_kiocb *req;
2315 /* order with ->result store in io_complete_rw_iopoll() */
2318 io_init_req_batch(&rb);
2319 while (!list_empty(done)) {
2320 req = list_first_entry(done, struct io_kiocb, inflight_entry);
2321 list_del(&req->inflight_entry);
2323 if (READ_ONCE(req->result) == -EAGAIN &&
2324 !(req->flags & REQ_F_DONT_REISSUE)) {
2325 req->iopoll_completed = 0;
2326 io_req_task_queue_reissue(req);
2330 __io_cqring_fill_event(ctx, req->user_data, req->result,
2331 io_put_rw_kbuf(req));
2334 if (req_ref_put_and_test(req))
2335 io_req_free_batch(&rb, req, &ctx->submit_state);
2338 io_commit_cqring(ctx);
2339 io_cqring_ev_posted_iopoll(ctx);
2340 io_req_free_batch_finish(ctx, &rb);
2343 static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
2346 struct io_kiocb *req, *tmp;
2351 * Only spin for completions if we don't have multiple devices hanging
2352 * off our complete list, and we're under the requested amount.
2354 spin = !ctx->poll_multi_queue && *nr_events < min;
2356 list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
2357 struct kiocb *kiocb = &req->rw.kiocb;
2361 * Move completed and retryable entries to our local lists.
2362 * If we find a request that requires polling, break out
2363 * and complete those lists first, if we have entries there.
2365 if (READ_ONCE(req->iopoll_completed)) {
2366 list_move_tail(&req->inflight_entry, &done);
2369 if (!list_empty(&done))
2372 ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin);
2373 if (unlikely(ret < 0))
2378 /* iopoll may have completed current req */
2379 if (READ_ONCE(req->iopoll_completed))
2380 list_move_tail(&req->inflight_entry, &done);
2383 if (!list_empty(&done))
2384 io_iopoll_complete(ctx, nr_events, &done);
2390 * We can't just wait for polled events to come to us, we have to actively
2391 * find and complete them.
2393 static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
2395 if (!(ctx->flags & IORING_SETUP_IOPOLL))
2398 mutex_lock(&ctx->uring_lock);
2399 while (!list_empty(&ctx->iopoll_list)) {
2400 unsigned int nr_events = 0;
2402 io_do_iopoll(ctx, &nr_events, 0);
2404 /* let it sleep and repeat later if can't complete a request */
2408 * Ensure we allow local-to-the-cpu processing to take place,
2409 * in this case we need to ensure that we reap all events.
2410 * Also let task_work, etc. to progress by releasing the mutex
2412 if (need_resched()) {
2413 mutex_unlock(&ctx->uring_lock);
2415 mutex_lock(&ctx->uring_lock);
2418 mutex_unlock(&ctx->uring_lock);
2421 static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
2423 unsigned int nr_events = 0;
2427 * We disallow the app entering submit/complete with polling, but we
2428 * still need to lock the ring to prevent racing with polled issue
2429 * that got punted to a workqueue.
2431 mutex_lock(&ctx->uring_lock);
2433 * Don't enter poll loop if we already have events pending.
2434 * If we do, we can potentially be spinning for commands that
2435 * already triggered a CQE (eg in error).
2437 if (test_bit(0, &ctx->check_cq_overflow))
2438 __io_cqring_overflow_flush(ctx, false);
2439 if (io_cqring_events(ctx))
2443 * If a submit got punted to a workqueue, we can have the
2444 * application entering polling for a command before it gets
2445 * issued. That app will hold the uring_lock for the duration
2446 * of the poll right here, so we need to take a breather every
2447 * now and then to ensure that the issue has a chance to add
2448 * the poll to the issued list. Otherwise we can spin here
2449 * forever, while the workqueue is stuck trying to acquire the
2452 if (list_empty(&ctx->iopoll_list)) {
2453 u32 tail = ctx->cached_cq_tail;
2455 mutex_unlock(&ctx->uring_lock);
2457 mutex_lock(&ctx->uring_lock);
2459 /* some requests don't go through iopoll_list */
2460 if (tail != ctx->cached_cq_tail ||
2461 list_empty(&ctx->iopoll_list))
2464 ret = io_do_iopoll(ctx, &nr_events, min);
2465 } while (!ret && nr_events < min && !need_resched());
2467 mutex_unlock(&ctx->uring_lock);
2471 static void kiocb_end_write(struct io_kiocb *req)
2474 * Tell lockdep we inherited freeze protection from submission
2477 if (req->flags & REQ_F_ISREG) {
2478 struct super_block *sb = file_inode(req->file)->i_sb;
2480 __sb_writers_acquired(sb, SB_FREEZE_WRITE);
2486 static bool io_resubmit_prep(struct io_kiocb *req)
2488 struct io_async_rw *rw = req->async_data;
2491 return !io_req_prep_async(req);
2492 /* may have left rw->iter inconsistent on -EIOCBQUEUED */
2493 iov_iter_revert(&rw->iter, req->result - iov_iter_count(&rw->iter));
2497 static bool io_rw_should_reissue(struct io_kiocb *req)
2499 umode_t mode = file_inode(req->file)->i_mode;
2500 struct io_ring_ctx *ctx = req->ctx;
2502 if (!S_ISBLK(mode) && !S_ISREG(mode))
2504 if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
2505 !(ctx->flags & IORING_SETUP_IOPOLL)))
2508 * If ref is dying, we might be running poll reap from the exit work.
2509 * Don't attempt to reissue from that path, just let it fail with
2512 if (percpu_ref_is_dying(&ctx->refs))
2515 * Play it safe and assume not safe to re-import and reissue if we're
2516 * not in the original thread group (or in task context).
2518 if (!same_thread_group(req->task, current) || !in_task())
2523 static bool io_resubmit_prep(struct io_kiocb *req)
2527 static bool io_rw_should_reissue(struct io_kiocb *req)
2533 static bool __io_complete_rw_common(struct io_kiocb *req, long res)
2535 if (req->rw.kiocb.ki_flags & IOCB_WRITE)
2536 kiocb_end_write(req);
2537 if (res != req->result) {
2538 if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
2539 io_rw_should_reissue(req)) {
2540 req->flags |= REQ_F_REISSUE;
2549 static void io_req_task_complete(struct io_kiocb *req)
2551 __io_req_complete(req, 0, req->result, io_put_rw_kbuf(req));
2554 static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
2555 unsigned int issue_flags)
2557 if (__io_complete_rw_common(req, res))
2559 io_req_task_complete(req);
2562 static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
2564 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2566 if (__io_complete_rw_common(req, res))
2569 req->io_task_work.func = io_req_task_complete;
2570 io_req_task_work_add(req);
2573 static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
2575 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2577 if (kiocb->ki_flags & IOCB_WRITE)
2578 kiocb_end_write(req);
2579 if (unlikely(res != req->result)) {
2580 if (!(res == -EAGAIN && io_rw_should_reissue(req) &&
2581 io_resubmit_prep(req))) {
2583 req->flags |= REQ_F_DONT_REISSUE;
2587 WRITE_ONCE(req->result, res);
2588 /* order with io_iopoll_complete() checking ->result */
2590 WRITE_ONCE(req->iopoll_completed, 1);
2594 * After the iocb has been issued, it's safe to be found on the poll list.
2595 * Adding the kiocb to the list AFTER submission ensures that we don't
2596 * find it from a io_do_iopoll() thread before the issuer is done
2597 * accessing the kiocb cookie.
2599 static void io_iopoll_req_issued(struct io_kiocb *req)
2601 struct io_ring_ctx *ctx = req->ctx;
2602 const bool in_async = io_wq_current_is_worker();
2604 /* workqueue context doesn't hold uring_lock, grab it now */
2605 if (unlikely(in_async))
2606 mutex_lock(&ctx->uring_lock);
2609 * Track whether we have multiple files in our lists. This will impact
2610 * how we do polling eventually, not spinning if we're on potentially
2611 * different devices.
2613 if (list_empty(&ctx->iopoll_list)) {
2614 ctx->poll_multi_queue = false;
2615 } else if (!ctx->poll_multi_queue) {
2616 struct io_kiocb *list_req;
2617 unsigned int queue_num0, queue_num1;
2619 list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
2622 if (list_req->file != req->file) {
2623 ctx->poll_multi_queue = true;
2625 queue_num0 = blk_qc_t_to_queue_num(list_req->rw.kiocb.ki_cookie);
2626 queue_num1 = blk_qc_t_to_queue_num(req->rw.kiocb.ki_cookie);
2627 if (queue_num0 != queue_num1)
2628 ctx->poll_multi_queue = true;
2633 * For fast devices, IO may have already completed. If it has, add
2634 * it to the front so we find it first.
2636 if (READ_ONCE(req->iopoll_completed))
2637 list_add(&req->inflight_entry, &ctx->iopoll_list);
2639 list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
2641 if (unlikely(in_async)) {
2643 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
2644 * in sq thread task context or in io worker task context. If
2645 * current task context is sq thread, we don't need to check
2646 * whether should wake up sq thread.
2648 if ((ctx->flags & IORING_SETUP_SQPOLL) &&
2649 wq_has_sleeper(&ctx->sq_data->wait))
2650 wake_up(&ctx->sq_data->wait);
2652 mutex_unlock(&ctx->uring_lock);
2656 static bool io_bdev_nowait(struct block_device *bdev)
2658 return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
2662 * If we tracked the file through the SCM inflight mechanism, we could support
2663 * any file. For now, just ensure that anything potentially problematic is done
2666 static bool __io_file_supports_nowait(struct file *file, int rw)
2668 umode_t mode = file_inode(file)->i_mode;
2670 if (S_ISBLK(mode)) {
2671 if (IS_ENABLED(CONFIG_BLOCK) &&
2672 io_bdev_nowait(I_BDEV(file->f_mapping->host)))
2678 if (S_ISREG(mode)) {
2679 if (IS_ENABLED(CONFIG_BLOCK) &&
2680 io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
2681 file->f_op != &io_uring_fops)
2686 /* any ->read/write should understand O_NONBLOCK */
2687 if (file->f_flags & O_NONBLOCK)
2690 if (!(file->f_mode & FMODE_NOWAIT))
2694 return file->f_op->read_iter != NULL;
2696 return file->f_op->write_iter != NULL;
2699 static bool io_file_supports_nowait(struct io_kiocb *req, int rw)
2701 if (rw == READ && (req->flags & REQ_F_NOWAIT_READ))
2703 else if (rw == WRITE && (req->flags & REQ_F_NOWAIT_WRITE))
2706 return __io_file_supports_nowait(req->file, rw);
2709 static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
2711 struct io_ring_ctx *ctx = req->ctx;
2712 struct kiocb *kiocb = &req->rw.kiocb;
2713 struct file *file = req->file;
2717 if (!io_req_ffs_set(req) && S_ISREG(file_inode(file)->i_mode))
2718 req->flags |= REQ_F_ISREG;
2720 kiocb->ki_pos = READ_ONCE(sqe->off);
2721 if (kiocb->ki_pos == -1 && !(file->f_mode & FMODE_STREAM)) {
2722 req->flags |= REQ_F_CUR_POS;
2723 kiocb->ki_pos = file->f_pos;
2725 kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
2726 kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
2727 ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
2731 /* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
2732 if ((kiocb->ki_flags & IOCB_NOWAIT) || (file->f_flags & O_NONBLOCK))
2733 req->flags |= REQ_F_NOWAIT;
2735 ioprio = READ_ONCE(sqe->ioprio);
2737 ret = ioprio_check_cap(ioprio);
2741 kiocb->ki_ioprio = ioprio;
2743 kiocb->ki_ioprio = get_current_ioprio();
2745 if (ctx->flags & IORING_SETUP_IOPOLL) {
2746 if (!(kiocb->ki_flags & IOCB_DIRECT) ||
2747 !kiocb->ki_filp->f_op->iopoll)
2750 kiocb->ki_flags |= IOCB_HIPRI;
2751 kiocb->ki_complete = io_complete_rw_iopoll;
2752 req->iopoll_completed = 0;
2754 if (kiocb->ki_flags & IOCB_HIPRI)
2756 kiocb->ki_complete = io_complete_rw;
2759 if (req->opcode == IORING_OP_READ_FIXED ||
2760 req->opcode == IORING_OP_WRITE_FIXED) {
2762 io_req_set_rsrc_node(req);
2765 req->rw.addr = READ_ONCE(sqe->addr);
2766 req->rw.len = READ_ONCE(sqe->len);
2767 req->buf_index = READ_ONCE(sqe->buf_index);
2771 static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
2777 case -ERESTARTNOINTR:
2778 case -ERESTARTNOHAND:
2779 case -ERESTART_RESTARTBLOCK:
2781 * We can't just restart the syscall, since previously
2782 * submitted sqes may already be in progress. Just fail this
2788 kiocb->ki_complete(kiocb, ret, 0);
2792 static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
2793 unsigned int issue_flags)
2795 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2796 struct io_async_rw *io = req->async_data;
2797 bool check_reissue = kiocb->ki_complete == io_complete_rw;
2799 /* add previously done IO, if any */
2800 if (io && io->bytes_done > 0) {
2802 ret = io->bytes_done;
2804 ret += io->bytes_done;
2807 if (req->flags & REQ_F_CUR_POS)
2808 req->file->f_pos = kiocb->ki_pos;
2809 if (ret >= 0 && check_reissue)
2810 __io_complete_rw(req, ret, 0, issue_flags);
2812 io_rw_done(kiocb, ret);
2814 if (check_reissue && (req->flags & REQ_F_REISSUE)) {
2815 req->flags &= ~REQ_F_REISSUE;
2816 if (io_resubmit_prep(req)) {
2817 io_req_task_queue_reissue(req);
2820 __io_req_complete(req, issue_flags, ret,
2821 io_put_rw_kbuf(req));
2826 static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
2827 struct io_mapped_ubuf *imu)
2829 size_t len = req->rw.len;
2830 u64 buf_end, buf_addr = req->rw.addr;
2833 if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
2835 /* not inside the mapped region */
2836 if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
2840 * May not be a start of buffer, set size appropriately
2841 * and advance us to the beginning.
2843 offset = buf_addr - imu->ubuf;
2844 iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
2848 * Don't use iov_iter_advance() here, as it's really slow for
2849 * using the latter parts of a big fixed buffer - it iterates
2850 * over each segment manually. We can cheat a bit here, because
2853 * 1) it's a BVEC iter, we set it up
2854 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2855 * first and last bvec
2857 * So just find our index, and adjust the iterator afterwards.
2858 * If the offset is within the first bvec (or the whole first
2859 * bvec, just use iov_iter_advance(). This makes it easier
2860 * since we can just skip the first segment, which may not
2861 * be PAGE_SIZE aligned.
2863 const struct bio_vec *bvec = imu->bvec;
2865 if (offset <= bvec->bv_len) {
2866 iov_iter_advance(iter, offset);
2868 unsigned long seg_skip;
2870 /* skip first vec */
2871 offset -= bvec->bv_len;
2872 seg_skip = 1 + (offset >> PAGE_SHIFT);
2874 iter->bvec = bvec + seg_skip;
2875 iter->nr_segs -= seg_skip;
2876 iter->count -= bvec->bv_len + offset;
2877 iter->iov_offset = offset & ~PAGE_MASK;
2884 static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
2886 struct io_ring_ctx *ctx = req->ctx;
2887 struct io_mapped_ubuf *imu = req->imu;
2888 u16 index, buf_index = req->buf_index;
2891 if (unlikely(buf_index >= ctx->nr_user_bufs))
2893 index = array_index_nospec(buf_index, ctx->nr_user_bufs);
2894 imu = READ_ONCE(ctx->user_bufs[index]);
2897 return __io_import_fixed(req, rw, iter, imu);
2900 static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
2903 mutex_unlock(&ctx->uring_lock);
2906 static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
2909 * "Normal" inline submissions always hold the uring_lock, since we
2910 * grab it from the system call. Same is true for the SQPOLL offload.
2911 * The only exception is when we've detached the request and issue it
2912 * from an async worker thread, grab the lock for that case.
2915 mutex_lock(&ctx->uring_lock);
2918 static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
2919 int bgid, struct io_buffer *kbuf,
2922 struct io_buffer *head;
2924 if (req->flags & REQ_F_BUFFER_SELECTED)
2927 io_ring_submit_lock(req->ctx, needs_lock);
2929 lockdep_assert_held(&req->ctx->uring_lock);
2931 head = xa_load(&req->ctx->io_buffers, bgid);
2933 if (!list_empty(&head->list)) {
2934 kbuf = list_last_entry(&head->list, struct io_buffer,
2936 list_del(&kbuf->list);
2939 xa_erase(&req->ctx->io_buffers, bgid);
2941 if (*len > kbuf->len)
2944 kbuf = ERR_PTR(-ENOBUFS);
2947 io_ring_submit_unlock(req->ctx, needs_lock);
2952 static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
2955 struct io_buffer *kbuf;
2958 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
2959 bgid = req->buf_index;
2960 kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
2963 req->rw.addr = (u64) (unsigned long) kbuf;
2964 req->flags |= REQ_F_BUFFER_SELECTED;
2965 return u64_to_user_ptr(kbuf->addr);
2968 #ifdef CONFIG_COMPAT
2969 static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
2972 struct compat_iovec __user *uiov;
2973 compat_ssize_t clen;
2977 uiov = u64_to_user_ptr(req->rw.addr);
2978 if (!access_ok(uiov, sizeof(*uiov)))
2980 if (__get_user(clen, &uiov->iov_len))
2986 buf = io_rw_buffer_select(req, &len, needs_lock);
2988 return PTR_ERR(buf);
2989 iov[0].iov_base = buf;
2990 iov[0].iov_len = (compat_size_t) len;
2995 static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
2998 struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
3002 if (copy_from_user(iov, uiov, sizeof(*uiov)))
3005 len = iov[0].iov_len;
3008 buf = io_rw_buffer_select(req, &len, needs_lock);
3010 return PTR_ERR(buf);
3011 iov[0].iov_base = buf;
3012 iov[0].iov_len = len;
3016 static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
3019 if (req->flags & REQ_F_BUFFER_SELECTED) {
3020 struct io_buffer *kbuf;
3022 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
3023 iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
3024 iov[0].iov_len = kbuf->len;
3027 if (req->rw.len != 1)
3030 #ifdef CONFIG_COMPAT
3031 if (req->ctx->compat)
3032 return io_compat_import(req, iov, needs_lock);
3035 return __io_iov_buffer_select(req, iov, needs_lock);
3038 static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
3039 struct iov_iter *iter, bool needs_lock)
3041 void __user *buf = u64_to_user_ptr(req->rw.addr);
3042 size_t sqe_len = req->rw.len;
3043 u8 opcode = req->opcode;
3046 if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
3048 return io_import_fixed(req, rw, iter);
3051 /* buffer index only valid with fixed read/write, or buffer select */
3052 if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
3055 if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
3056 if (req->flags & REQ_F_BUFFER_SELECT) {
3057 buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
3059 return PTR_ERR(buf);
3060 req->rw.len = sqe_len;
3063 ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
3068 if (req->flags & REQ_F_BUFFER_SELECT) {
3069 ret = io_iov_buffer_select(req, *iovec, needs_lock);
3071 iov_iter_init(iter, rw, *iovec, 1, (*iovec)->iov_len);
3076 return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
3080 static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
3082 return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
3086 * For files that don't have ->read_iter() and ->write_iter(), handle them
3087 * by looping over ->read() or ->write() manually.
3089 static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
3091 struct kiocb *kiocb = &req->rw.kiocb;
3092 struct file *file = req->file;
3096 * Don't support polled IO through this interface, and we can't
3097 * support non-blocking either. For the latter, this just causes
3098 * the kiocb to be handled from an async context.
3100 if (kiocb->ki_flags & IOCB_HIPRI)
3102 if (kiocb->ki_flags & IOCB_NOWAIT)
3105 while (iov_iter_count(iter)) {
3109 if (!iov_iter_is_bvec(iter)) {
3110 iovec = iov_iter_iovec(iter);
3112 iovec.iov_base = u64_to_user_ptr(req->rw.addr);
3113 iovec.iov_len = req->rw.len;
3117 nr = file->f_op->read(file, iovec.iov_base,
3118 iovec.iov_len, io_kiocb_ppos(kiocb));
3120 nr = file->f_op->write(file, iovec.iov_base,
3121 iovec.iov_len, io_kiocb_ppos(kiocb));
3130 if (nr != iovec.iov_len)
3134 iov_iter_advance(iter, nr);
3140 static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
3141 const struct iovec *fast_iov, struct iov_iter *iter)
3143 struct io_async_rw *rw = req->async_data;
3145 memcpy(&rw->iter, iter, sizeof(*iter));
3146 rw->free_iovec = iovec;
3148 /* can only be fixed buffers, no need to do anything */
3149 if (iov_iter_is_bvec(iter))
3152 unsigned iov_off = 0;
3154 rw->iter.iov = rw->fast_iov;
3155 if (iter->iov != fast_iov) {
3156 iov_off = iter->iov - fast_iov;
3157 rw->iter.iov += iov_off;
3159 if (rw->fast_iov != fast_iov)
3160 memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
3161 sizeof(struct iovec) * iter->nr_segs);
3163 req->flags |= REQ_F_NEED_CLEANUP;
3167 static inline int io_alloc_async_data(struct io_kiocb *req)
3169 WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
3170 req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
3171 return req->async_data == NULL;
3174 static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
3175 const struct iovec *fast_iov,
3176 struct iov_iter *iter, bool force)
3178 if (!force && !io_op_defs[req->opcode].needs_async_setup)
3180 if (!req->async_data) {
3181 if (io_alloc_async_data(req)) {
3186 io_req_map_rw(req, iovec, fast_iov, iter);
3191 static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
3193 struct io_async_rw *iorw = req->async_data;
3194 struct iovec *iov = iorw->fast_iov;
3197 ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
3198 if (unlikely(ret < 0))
3201 iorw->bytes_done = 0;
3202 iorw->free_iovec = iov;
3204 req->flags |= REQ_F_NEED_CLEANUP;
3208 static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3210 if (unlikely(!(req->file->f_mode & FMODE_READ)))
3212 return io_prep_rw(req, sqe);
3216 * This is our waitqueue callback handler, registered through lock_page_async()
3217 * when we initially tried to do the IO with the iocb armed our waitqueue.
3218 * This gets called when the page is unlocked, and we generally expect that to
3219 * happen when the page IO is completed and the page is now uptodate. This will
3220 * queue a task_work based retry of the operation, attempting to copy the data
3221 * again. If the latter fails because the page was NOT uptodate, then we will
3222 * do a thread based blocking retry of the operation. That's the unexpected
3225 static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
3226 int sync, void *arg)
3228 struct wait_page_queue *wpq;
3229 struct io_kiocb *req = wait->private;
3230 struct wait_page_key *key = arg;
3232 wpq = container_of(wait, struct wait_page_queue, wait);
3234 if (!wake_page_match(wpq, key))
3237 req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
3238 list_del_init(&wait->entry);
3239 io_req_task_queue(req);
3244 * This controls whether a given IO request should be armed for async page
3245 * based retry. If we return false here, the request is handed to the async
3246 * worker threads for retry. If we're doing buffered reads on a regular file,
3247 * we prepare a private wait_page_queue entry and retry the operation. This
3248 * will either succeed because the page is now uptodate and unlocked, or it
3249 * will register a callback when the page is unlocked at IO completion. Through
3250 * that callback, io_uring uses task_work to setup a retry of the operation.
3251 * That retry will attempt the buffered read again. The retry will generally
3252 * succeed, or in rare cases where it fails, we then fall back to using the
3253 * async worker threads for a blocking retry.
3255 static bool io_rw_should_retry(struct io_kiocb *req)
3257 struct io_async_rw *rw = req->async_data;
3258 struct wait_page_queue *wait = &rw->wpq;
3259 struct kiocb *kiocb = &req->rw.kiocb;
3261 /* never retry for NOWAIT, we just complete with -EAGAIN */
3262 if (req->flags & REQ_F_NOWAIT)
3265 /* Only for buffered IO */
3266 if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
3270 * just use poll if we can, and don't attempt if the fs doesn't
3271 * support callback based unlocks
3273 if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
3276 wait->wait.func = io_async_buf_func;
3277 wait->wait.private = req;
3278 wait->wait.flags = 0;
3279 INIT_LIST_HEAD(&wait->wait.entry);
3280 kiocb->ki_flags |= IOCB_WAITQ;
3281 kiocb->ki_flags &= ~IOCB_NOWAIT;
3282 kiocb->ki_waitq = wait;
3286 static inline int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
3288 if (req->file->f_op->read_iter)
3289 return call_read_iter(req->file, &req->rw.kiocb, iter);
3290 else if (req->file->f_op->read)
3291 return loop_rw_iter(READ, req, iter);
3296 static int io_read(struct io_kiocb *req, unsigned int issue_flags)
3298 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
3299 struct kiocb *kiocb = &req->rw.kiocb;
3300 struct iov_iter __iter, *iter = &__iter;
3301 struct io_async_rw *rw = req->async_data;
3302 ssize_t io_size, ret, ret2;
3303 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3309 ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
3313 io_size = iov_iter_count(iter);
3314 req->result = io_size;
3316 /* Ensure we clear previously set non-block flag */
3317 if (!force_nonblock)
3318 kiocb->ki_flags &= ~IOCB_NOWAIT;
3320 kiocb->ki_flags |= IOCB_NOWAIT;
3322 /* If the file doesn't support async, just async punt */
3323 if (force_nonblock && !io_file_supports_nowait(req, READ)) {
3324 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
3325 return ret ?: -EAGAIN;
3328 ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), io_size);
3329 if (unlikely(ret)) {
3334 ret = io_iter_do_read(req, iter);
3336 if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
3337 req->flags &= ~REQ_F_REISSUE;
3338 /* IOPOLL retry should happen for io-wq threads */
3339 if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
3341 /* no retry on NONBLOCK nor RWF_NOWAIT */
3342 if (req->flags & REQ_F_NOWAIT)
3344 /* some cases will consume bytes even on error returns */
3345 iov_iter_revert(iter, io_size - iov_iter_count(iter));
3347 } else if (ret == -EIOCBQUEUED) {
3349 } else if (ret <= 0 || ret == io_size || !force_nonblock ||
3350 (req->flags & REQ_F_NOWAIT) || !(req->flags & REQ_F_ISREG)) {
3351 /* read all, failed, already did sync or don't want to retry */
3355 ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
3360 rw = req->async_data;
3361 /* now use our persistent iterator, if we aren't already */
3366 rw->bytes_done += ret;
3367 /* if we can retry, do so with the callbacks armed */
3368 if (!io_rw_should_retry(req)) {
3369 kiocb->ki_flags &= ~IOCB_WAITQ;
3374 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3375 * we get -EIOCBQUEUED, then we'll get a notification when the
3376 * desired page gets unlocked. We can also get a partial read
3377 * here, and if we do, then just retry at the new offset.
3379 ret = io_iter_do_read(req, iter);
3380 if (ret == -EIOCBQUEUED)
3382 /* we got some bytes, but not all. retry. */
3383 kiocb->ki_flags &= ~IOCB_WAITQ;
3384 } while (ret > 0 && ret < io_size);
3386 kiocb_done(kiocb, ret, issue_flags);
3388 /* it's faster to check here then delegate to kfree */
3394 static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3396 if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
3398 return io_prep_rw(req, sqe);
3401 static int io_write(struct io_kiocb *req, unsigned int issue_flags)
3403 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
3404 struct kiocb *kiocb = &req->rw.kiocb;
3405 struct iov_iter __iter, *iter = &__iter;
3406 struct io_async_rw *rw = req->async_data;
3407 ssize_t ret, ret2, io_size;
3408 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3414 ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
3418 io_size = iov_iter_count(iter);
3419 req->result = io_size;
3421 /* Ensure we clear previously set non-block flag */
3422 if (!force_nonblock)
3423 kiocb->ki_flags &= ~IOCB_NOWAIT;
3425 kiocb->ki_flags |= IOCB_NOWAIT;
3427 /* If the file doesn't support async, just async punt */
3428 if (force_nonblock && !io_file_supports_nowait(req, WRITE))
3431 /* file path doesn't support NOWAIT for non-direct_IO */
3432 if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
3433 (req->flags & REQ_F_ISREG))
3436 ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), io_size);
3441 * Open-code file_start_write here to grab freeze protection,
3442 * which will be released by another thread in
3443 * io_complete_rw(). Fool lockdep by telling it the lock got
3444 * released so that it doesn't complain about the held lock when
3445 * we return to userspace.
3447 if (req->flags & REQ_F_ISREG) {
3448 sb_start_write(file_inode(req->file)->i_sb);
3449 __sb_writers_release(file_inode(req->file)->i_sb,
3452 kiocb->ki_flags |= IOCB_WRITE;
3454 if (req->file->f_op->write_iter)
3455 ret2 = call_write_iter(req->file, kiocb, iter);
3456 else if (req->file->f_op->write)
3457 ret2 = loop_rw_iter(WRITE, req, iter);
3461 if (req->flags & REQ_F_REISSUE) {
3462 req->flags &= ~REQ_F_REISSUE;
3467 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3468 * retry them without IOCB_NOWAIT.
3470 if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
3472 /* no retry on NONBLOCK nor RWF_NOWAIT */
3473 if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
3475 if (!force_nonblock || ret2 != -EAGAIN) {
3476 /* IOPOLL retry should happen for io-wq threads */
3477 if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
3480 kiocb_done(kiocb, ret2, issue_flags);
3483 /* some cases will consume bytes even on error returns */
3484 iov_iter_revert(iter, io_size - iov_iter_count(iter));
3485 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
3486 return ret ?: -EAGAIN;
3489 /* it's reportedly faster than delegating the null check to kfree() */
3495 static int io_renameat_prep(struct io_kiocb *req,
3496 const struct io_uring_sqe *sqe)
3498 struct io_rename *ren = &req->rename;
3499 const char __user *oldf, *newf;
3501 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3503 if (sqe->ioprio || sqe->buf_index)
3505 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3508 ren->old_dfd = READ_ONCE(sqe->fd);
3509 oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
3510 newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3511 ren->new_dfd = READ_ONCE(sqe->len);
3512 ren->flags = READ_ONCE(sqe->rename_flags);
3514 ren->oldpath = getname(oldf);
3515 if (IS_ERR(ren->oldpath))
3516 return PTR_ERR(ren->oldpath);
3518 ren->newpath = getname(newf);
3519 if (IS_ERR(ren->newpath)) {
3520 putname(ren->oldpath);
3521 return PTR_ERR(ren->newpath);
3524 req->flags |= REQ_F_NEED_CLEANUP;
3528 static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
3530 struct io_rename *ren = &req->rename;
3533 if (issue_flags & IO_URING_F_NONBLOCK)
3536 ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
3537 ren->newpath, ren->flags);
3539 req->flags &= ~REQ_F_NEED_CLEANUP;
3542 io_req_complete(req, ret);
3546 static int io_unlinkat_prep(struct io_kiocb *req,
3547 const struct io_uring_sqe *sqe)
3549 struct io_unlink *un = &req->unlink;
3550 const char __user *fname;
3552 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3554 if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index)
3556 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3559 un->dfd = READ_ONCE(sqe->fd);
3561 un->flags = READ_ONCE(sqe->unlink_flags);
3562 if (un->flags & ~AT_REMOVEDIR)
3565 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
3566 un->filename = getname(fname);
3567 if (IS_ERR(un->filename))
3568 return PTR_ERR(un->filename);
3570 req->flags |= REQ_F_NEED_CLEANUP;
3574 static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
3576 struct io_unlink *un = &req->unlink;
3579 if (issue_flags & IO_URING_F_NONBLOCK)
3582 if (un->flags & AT_REMOVEDIR)
3583 ret = do_rmdir(un->dfd, un->filename);
3585 ret = do_unlinkat(un->dfd, un->filename);
3587 req->flags &= ~REQ_F_NEED_CLEANUP;
3590 io_req_complete(req, ret);
3594 static int io_shutdown_prep(struct io_kiocb *req,
3595 const struct io_uring_sqe *sqe)
3597 #if defined(CONFIG_NET)
3598 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3600 if (sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags ||
3604 req->shutdown.how = READ_ONCE(sqe->len);
3611 static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
3613 #if defined(CONFIG_NET)
3614 struct socket *sock;
3617 if (issue_flags & IO_URING_F_NONBLOCK)
3620 sock = sock_from_file(req->file);
3621 if (unlikely(!sock))
3624 ret = __sys_shutdown_sock(sock, req->shutdown.how);
3627 io_req_complete(req, ret);
3634 static int __io_splice_prep(struct io_kiocb *req,
3635 const struct io_uring_sqe *sqe)
3637 struct io_splice *sp = &req->splice;
3638 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
3640 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3644 sp->len = READ_ONCE(sqe->len);
3645 sp->flags = READ_ONCE(sqe->splice_flags);
3647 if (unlikely(sp->flags & ~valid_flags))
3650 sp->file_in = io_file_get(req->ctx, req, READ_ONCE(sqe->splice_fd_in),
3651 (sp->flags & SPLICE_F_FD_IN_FIXED));
3654 req->flags |= REQ_F_NEED_CLEANUP;
3658 static int io_tee_prep(struct io_kiocb *req,
3659 const struct io_uring_sqe *sqe)
3661 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
3663 return __io_splice_prep(req, sqe);
3666 static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
3668 struct io_splice *sp = &req->splice;
3669 struct file *in = sp->file_in;
3670 struct file *out = sp->file_out;
3671 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3674 if (issue_flags & IO_URING_F_NONBLOCK)
3677 ret = do_tee(in, out, sp->len, flags);
3679 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
3681 req->flags &= ~REQ_F_NEED_CLEANUP;
3685 io_req_complete(req, ret);
3689 static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3691 struct io_splice *sp = &req->splice;
3693 sp->off_in = READ_ONCE(sqe->splice_off_in);
3694 sp->off_out = READ_ONCE(sqe->off);
3695 return __io_splice_prep(req, sqe);
3698 static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
3700 struct io_splice *sp = &req->splice;
3701 struct file *in = sp->file_in;
3702 struct file *out = sp->file_out;
3703 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3704 loff_t *poff_in, *poff_out;
3707 if (issue_flags & IO_URING_F_NONBLOCK)
3710 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
3711 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
3714 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
3716 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
3718 req->flags &= ~REQ_F_NEED_CLEANUP;
3722 io_req_complete(req, ret);
3727 * IORING_OP_NOP just posts a completion event, nothing else.
3729 static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
3731 struct io_ring_ctx *ctx = req->ctx;
3733 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
3736 __io_req_complete(req, issue_flags, 0, 0);
3740 static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3742 struct io_ring_ctx *ctx = req->ctx;
3747 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
3749 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
3752 req->sync.flags = READ_ONCE(sqe->fsync_flags);
3753 if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
3756 req->sync.off = READ_ONCE(sqe->off);
3757 req->sync.len = READ_ONCE(sqe->len);
3761 static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
3763 loff_t end = req->sync.off + req->sync.len;
3766 /* fsync always requires a blocking context */
3767 if (issue_flags & IO_URING_F_NONBLOCK)
3770 ret = vfs_fsync_range(req->file, req->sync.off,
3771 end > 0 ? end : LLONG_MAX,
3772 req->sync.flags & IORING_FSYNC_DATASYNC);
3775 io_req_complete(req, ret);
3779 static int io_fallocate_prep(struct io_kiocb *req,
3780 const struct io_uring_sqe *sqe)
3782 if (sqe->ioprio || sqe->buf_index || sqe->rw_flags)
3784 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3787 req->sync.off = READ_ONCE(sqe->off);
3788 req->sync.len = READ_ONCE(sqe->addr);
3789 req->sync.mode = READ_ONCE(sqe->len);
3793 static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
3797 /* fallocate always requiring blocking context */
3798 if (issue_flags & IO_URING_F_NONBLOCK)
3800 ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
3804 io_req_complete(req, ret);
3808 static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3810 const char __user *fname;
3813 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3815 if (unlikely(sqe->ioprio || sqe->buf_index))
3817 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3820 /* open.how should be already initialised */
3821 if (!(req->open.how.flags & O_PATH) && force_o_largefile())
3822 req->open.how.flags |= O_LARGEFILE;
3824 req->open.dfd = READ_ONCE(sqe->fd);
3825 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
3826 req->open.filename = getname(fname);
3827 if (IS_ERR(req->open.filename)) {
3828 ret = PTR_ERR(req->open.filename);
3829 req->open.filename = NULL;
3832 req->open.nofile = rlimit(RLIMIT_NOFILE);
3833 req->flags |= REQ_F_NEED_CLEANUP;
3837 static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3839 u64 mode = READ_ONCE(sqe->len);
3840 u64 flags = READ_ONCE(sqe->open_flags);
3842 req->open.how = build_open_how(flags, mode);
3843 return __io_openat_prep(req, sqe);
3846 static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3848 struct open_how __user *how;
3852 how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3853 len = READ_ONCE(sqe->len);
3854 if (len < OPEN_HOW_SIZE_VER0)
3857 ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
3862 return __io_openat_prep(req, sqe);
3865 static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
3867 struct open_flags op;
3870 bool resolve_nonblock;
3873 ret = build_open_flags(&req->open.how, &op);
3876 nonblock_set = op.open_flag & O_NONBLOCK;
3877 resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
3878 if (issue_flags & IO_URING_F_NONBLOCK) {
3880 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
3881 * it'll always -EAGAIN
3883 if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
3885 op.lookup_flags |= LOOKUP_CACHED;
3886 op.open_flag |= O_NONBLOCK;
3889 ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
3893 file = do_filp_open(req->open.dfd, req->open.filename, &op);
3896 * We could hang on to this 'fd' on retrying, but seems like
3897 * marginal gain for something that is now known to be a slower
3898 * path. So just put it, and we'll get a new one when we retry.
3902 ret = PTR_ERR(file);
3903 /* only retry if RESOLVE_CACHED wasn't already set by application */
3904 if (ret == -EAGAIN &&
3905 (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)))
3910 if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
3911 file->f_flags &= ~O_NONBLOCK;
3912 fsnotify_open(file);
3913 fd_install(ret, file);
3915 putname(req->open.filename);
3916 req->flags &= ~REQ_F_NEED_CLEANUP;
3919 __io_req_complete(req, issue_flags, ret, 0);
3923 static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
3925 return io_openat2(req, issue_flags);
3928 static int io_remove_buffers_prep(struct io_kiocb *req,
3929 const struct io_uring_sqe *sqe)
3931 struct io_provide_buf *p = &req->pbuf;
3934 if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off)
3937 tmp = READ_ONCE(sqe->fd);
3938 if (!tmp || tmp > USHRT_MAX)
3941 memset(p, 0, sizeof(*p));
3943 p->bgid = READ_ONCE(sqe->buf_group);
3947 static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
3948 int bgid, unsigned nbufs)
3952 /* shouldn't happen */
3956 /* the head kbuf is the list itself */
3957 while (!list_empty(&buf->list)) {
3958 struct io_buffer *nxt;
3960 nxt = list_first_entry(&buf->list, struct io_buffer, list);
3961 list_del(&nxt->list);
3968 xa_erase(&ctx->io_buffers, bgid);
3973 static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
3975 struct io_provide_buf *p = &req->pbuf;
3976 struct io_ring_ctx *ctx = req->ctx;
3977 struct io_buffer *head;
3979 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3981 io_ring_submit_lock(ctx, !force_nonblock);
3983 lockdep_assert_held(&ctx->uring_lock);
3986 head = xa_load(&ctx->io_buffers, p->bgid);
3988 ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
3992 /* complete before unlock, IOPOLL may need the lock */
3993 __io_req_complete(req, issue_flags, ret, 0);
3994 io_ring_submit_unlock(ctx, !force_nonblock);
3998 static int io_provide_buffers_prep(struct io_kiocb *req,
3999 const struct io_uring_sqe *sqe)
4001 unsigned long size, tmp_check;
4002 struct io_provide_buf *p = &req->pbuf;
4005 if (sqe->ioprio || sqe->rw_flags)
4008 tmp = READ_ONCE(sqe->fd);
4009 if (!tmp || tmp > USHRT_MAX)
4012 p->addr = READ_ONCE(sqe->addr);
4013 p->len = READ_ONCE(sqe->len);
4015 if (check_mul_overflow((unsigned long)p->len, (unsigned long)p->nbufs,
4018 if (check_add_overflow((unsigned long)p->addr, size, &tmp_check))
4021 size = (unsigned long)p->len * p->nbufs;
4022 if (!access_ok(u64_to_user_ptr(p->addr), size))
4025 p->bgid = READ_ONCE(sqe->buf_group);
4026 tmp = READ_ONCE(sqe->off);
4027 if (tmp > USHRT_MAX)
4033 static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
4035 struct io_buffer *buf;
4036 u64 addr = pbuf->addr;
4037 int i, bid = pbuf->bid;
4039 for (i = 0; i < pbuf->nbufs; i++) {
4040 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
4045 buf->len = min_t(__u32, pbuf->len, MAX_RW_COUNT);
4050 INIT_LIST_HEAD(&buf->list);
4053 list_add_tail(&buf->list, &(*head)->list);
4057 return i ? i : -ENOMEM;
4060 static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
4062 struct io_provide_buf *p = &req->pbuf;
4063 struct io_ring_ctx *ctx = req->ctx;
4064 struct io_buffer *head, *list;
4066 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4068 io_ring_submit_lock(ctx, !force_nonblock);
4070 lockdep_assert_held(&ctx->uring_lock);
4072 list = head = xa_load(&ctx->io_buffers, p->bgid);
4074 ret = io_add_buffers(p, &head);
4075 if (ret >= 0 && !list) {
4076 ret = xa_insert(&ctx->io_buffers, p->bgid, head, GFP_KERNEL);
4078 __io_remove_buffers(ctx, head, p->bgid, -1U);
4082 /* complete before unlock, IOPOLL may need the lock */
4083 __io_req_complete(req, issue_flags, ret, 0);
4084 io_ring_submit_unlock(ctx, !force_nonblock);
4088 static int io_epoll_ctl_prep(struct io_kiocb *req,
4089 const struct io_uring_sqe *sqe)
4091 #if defined(CONFIG_EPOLL)
4092 if (sqe->ioprio || sqe->buf_index)
4094 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4097 req->epoll.epfd = READ_ONCE(sqe->fd);
4098 req->epoll.op = READ_ONCE(sqe->len);
4099 req->epoll.fd = READ_ONCE(sqe->off);
4101 if (ep_op_has_event(req->epoll.op)) {
4102 struct epoll_event __user *ev;
4104 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
4105 if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
4115 static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
4117 #if defined(CONFIG_EPOLL)
4118 struct io_epoll *ie = &req->epoll;
4120 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4122 ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
4123 if (force_nonblock && ret == -EAGAIN)
4128 __io_req_complete(req, issue_flags, ret, 0);
4135 static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4137 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4138 if (sqe->ioprio || sqe->buf_index || sqe->off)
4140 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4143 req->madvise.addr = READ_ONCE(sqe->addr);
4144 req->madvise.len = READ_ONCE(sqe->len);
4145 req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
4152 static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
4154 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4155 struct io_madvise *ma = &req->madvise;
4158 if (issue_flags & IO_URING_F_NONBLOCK)
4161 ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
4164 io_req_complete(req, ret);
4171 static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4173 if (sqe->ioprio || sqe->buf_index || sqe->addr)
4175 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4178 req->fadvise.offset = READ_ONCE(sqe->off);
4179 req->fadvise.len = READ_ONCE(sqe->len);
4180 req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
4184 static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
4186 struct io_fadvise *fa = &req->fadvise;
4189 if (issue_flags & IO_URING_F_NONBLOCK) {
4190 switch (fa->advice) {
4191 case POSIX_FADV_NORMAL:
4192 case POSIX_FADV_RANDOM:
4193 case POSIX_FADV_SEQUENTIAL:
4200 ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
4203 __io_req_complete(req, issue_flags, ret, 0);
4207 static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4209 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4211 if (sqe->ioprio || sqe->buf_index)
4213 if (req->flags & REQ_F_FIXED_FILE)
4216 req->statx.dfd = READ_ONCE(sqe->fd);
4217 req->statx.mask = READ_ONCE(sqe->len);
4218 req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
4219 req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4220 req->statx.flags = READ_ONCE(sqe->statx_flags);
4225 static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
4227 struct io_statx *ctx = &req->statx;
4230 if (issue_flags & IO_URING_F_NONBLOCK)
4233 ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
4238 io_req_complete(req, ret);
4242 static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4244 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4246 if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
4247 sqe->rw_flags || sqe->buf_index)
4249 if (req->flags & REQ_F_FIXED_FILE)
4252 req->close.fd = READ_ONCE(sqe->fd);
4256 static int io_close(struct io_kiocb *req, unsigned int issue_flags)
4258 struct files_struct *files = current->files;
4259 struct io_close *close = &req->close;
4260 struct fdtable *fdt;
4261 struct file *file = NULL;
4264 spin_lock(&files->file_lock);
4265 fdt = files_fdtable(files);
4266 if (close->fd >= fdt->max_fds) {
4267 spin_unlock(&files->file_lock);
4270 file = fdt->fd[close->fd];
4271 if (!file || file->f_op == &io_uring_fops) {
4272 spin_unlock(&files->file_lock);
4277 /* if the file has a flush method, be safe and punt to async */
4278 if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
4279 spin_unlock(&files->file_lock);
4283 ret = __close_fd_get_file(close->fd, &file);
4284 spin_unlock(&files->file_lock);
4291 /* No ->flush() or already async, safely close from here */
4292 ret = filp_close(file, current->files);
4298 __io_req_complete(req, issue_flags, ret, 0);
4302 static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4304 struct io_ring_ctx *ctx = req->ctx;
4306 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
4308 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index))
4311 req->sync.off = READ_ONCE(sqe->off);
4312 req->sync.len = READ_ONCE(sqe->len);
4313 req->sync.flags = READ_ONCE(sqe->sync_range_flags);
4317 static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
4321 /* sync_file_range always requires a blocking context */
4322 if (issue_flags & IO_URING_F_NONBLOCK)
4325 ret = sync_file_range(req->file, req->sync.off, req->sync.len,
4329 io_req_complete(req, ret);
4333 #if defined(CONFIG_NET)
4334 static int io_setup_async_msg(struct io_kiocb *req,
4335 struct io_async_msghdr *kmsg)
4337 struct io_async_msghdr *async_msg = req->async_data;
4341 if (io_alloc_async_data(req)) {
4342 kfree(kmsg->free_iov);
4345 async_msg = req->async_data;
4346 req->flags |= REQ_F_NEED_CLEANUP;
4347 memcpy(async_msg, kmsg, sizeof(*kmsg));
4348 async_msg->msg.msg_name = &async_msg->addr;
4349 /* if were using fast_iov, set it to the new one */
4350 if (!async_msg->free_iov)
4351 async_msg->msg.msg_iter.iov = async_msg->fast_iov;
4356 static int io_sendmsg_copy_hdr(struct io_kiocb *req,
4357 struct io_async_msghdr *iomsg)
4359 iomsg->msg.msg_name = &iomsg->addr;
4360 iomsg->free_iov = iomsg->fast_iov;
4361 return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
4362 req->sr_msg.msg_flags, &iomsg->free_iov);
4365 static int io_sendmsg_prep_async(struct io_kiocb *req)
4369 ret = io_sendmsg_copy_hdr(req, req->async_data);
4371 req->flags |= REQ_F_NEED_CLEANUP;
4375 static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4377 struct io_sr_msg *sr = &req->sr_msg;
4379 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4382 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
4383 sr->len = READ_ONCE(sqe->len);
4384 sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
4385 if (sr->msg_flags & MSG_DONTWAIT)
4386 req->flags |= REQ_F_NOWAIT;
4388 #ifdef CONFIG_COMPAT
4389 if (req->ctx->compat)
4390 sr->msg_flags |= MSG_CMSG_COMPAT;
4395 static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
4397 struct io_async_msghdr iomsg, *kmsg;
4398 struct socket *sock;
4403 sock = sock_from_file(req->file);
4404 if (unlikely(!sock))
4407 kmsg = req->async_data;
4409 ret = io_sendmsg_copy_hdr(req, &iomsg);
4415 flags = req->sr_msg.msg_flags;
4416 if (issue_flags & IO_URING_F_NONBLOCK)
4417 flags |= MSG_DONTWAIT;
4418 if (flags & MSG_WAITALL)
4419 min_ret = iov_iter_count(&kmsg->msg.msg_iter);
4421 ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
4422 if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
4423 return io_setup_async_msg(req, kmsg);
4424 if (ret == -ERESTARTSYS)
4427 /* fast path, check for non-NULL to avoid function call */
4429 kfree(kmsg->free_iov);
4430 req->flags &= ~REQ_F_NEED_CLEANUP;
4433 __io_req_complete(req, issue_flags, ret, 0);
4437 static int io_send(struct io_kiocb *req, unsigned int issue_flags)
4439 struct io_sr_msg *sr = &req->sr_msg;
4442 struct socket *sock;
4447 sock = sock_from_file(req->file);
4448 if (unlikely(!sock))
4451 ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
4455 msg.msg_name = NULL;
4456 msg.msg_control = NULL;
4457 msg.msg_controllen = 0;
4458 msg.msg_namelen = 0;
4460 flags = req->sr_msg.msg_flags;
4461 if (issue_flags & IO_URING_F_NONBLOCK)
4462 flags |= MSG_DONTWAIT;
4463 if (flags & MSG_WAITALL)
4464 min_ret = iov_iter_count(&msg.msg_iter);
4466 msg.msg_flags = flags;
4467 ret = sock_sendmsg(sock, &msg);
4468 if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
4470 if (ret == -ERESTARTSYS)
4475 __io_req_complete(req, issue_flags, ret, 0);
4479 static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
4480 struct io_async_msghdr *iomsg)
4482 struct io_sr_msg *sr = &req->sr_msg;
4483 struct iovec __user *uiov;
4487 ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
4488 &iomsg->uaddr, &uiov, &iov_len);
4492 if (req->flags & REQ_F_BUFFER_SELECT) {
4495 if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
4497 sr->len = iomsg->fast_iov[0].iov_len;
4498 iomsg->free_iov = NULL;
4500 iomsg->free_iov = iomsg->fast_iov;
4501 ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
4502 &iomsg->free_iov, &iomsg->msg.msg_iter,
4511 #ifdef CONFIG_COMPAT
4512 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
4513 struct io_async_msghdr *iomsg)
4515 struct io_sr_msg *sr = &req->sr_msg;
4516 struct compat_iovec __user *uiov;
4521 ret = __get_compat_msghdr(&iomsg->msg, sr->umsg_compat, &iomsg->uaddr,
4526 uiov = compat_ptr(ptr);
4527 if (req->flags & REQ_F_BUFFER_SELECT) {
4528 compat_ssize_t clen;
4532 if (!access_ok(uiov, sizeof(*uiov)))
4534 if (__get_user(clen, &uiov->iov_len))
4539 iomsg->free_iov = NULL;
4541 iomsg->free_iov = iomsg->fast_iov;
4542 ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
4543 UIO_FASTIOV, &iomsg->free_iov,
4544 &iomsg->msg.msg_iter, true);
4553 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
4554 struct io_async_msghdr *iomsg)
4556 iomsg->msg.msg_name = &iomsg->addr;
4558 #ifdef CONFIG_COMPAT
4559 if (req->ctx->compat)
4560 return __io_compat_recvmsg_copy_hdr(req, iomsg);
4563 return __io_recvmsg_copy_hdr(req, iomsg);
4566 static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
4569 struct io_sr_msg *sr = &req->sr_msg;
4570 struct io_buffer *kbuf;
4572 kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
4577 req->flags |= REQ_F_BUFFER_SELECTED;
4581 static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
4583 return io_put_kbuf(req, req->sr_msg.kbuf);
4586 static int io_recvmsg_prep_async(struct io_kiocb *req)
4590 ret = io_recvmsg_copy_hdr(req, req->async_data);
4592 req->flags |= REQ_F_NEED_CLEANUP;
4596 static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4598 struct io_sr_msg *sr = &req->sr_msg;
4600 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4603 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
4604 sr->len = READ_ONCE(sqe->len);
4605 sr->bgid = READ_ONCE(sqe->buf_group);
4606 sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
4607 if (sr->msg_flags & MSG_DONTWAIT)
4608 req->flags |= REQ_F_NOWAIT;
4610 #ifdef CONFIG_COMPAT
4611 if (req->ctx->compat)
4612 sr->msg_flags |= MSG_CMSG_COMPAT;
4617 static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
4619 struct io_async_msghdr iomsg, *kmsg;
4620 struct socket *sock;
4621 struct io_buffer *kbuf;
4624 int ret, cflags = 0;
4625 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4627 sock = sock_from_file(req->file);
4628 if (unlikely(!sock))
4631 kmsg = req->async_data;
4633 ret = io_recvmsg_copy_hdr(req, &iomsg);
4639 if (req->flags & REQ_F_BUFFER_SELECT) {
4640 kbuf = io_recv_buffer_select(req, !force_nonblock);
4642 return PTR_ERR(kbuf);
4643 kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
4644 kmsg->fast_iov[0].iov_len = req->sr_msg.len;
4645 iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov,
4646 1, req->sr_msg.len);
4649 flags = req->sr_msg.msg_flags;
4651 flags |= MSG_DONTWAIT;
4652 if (flags & MSG_WAITALL)
4653 min_ret = iov_iter_count(&kmsg->msg.msg_iter);
4655 ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
4656 kmsg->uaddr, flags);
4657 if (force_nonblock && ret == -EAGAIN)
4658 return io_setup_async_msg(req, kmsg);
4659 if (ret == -ERESTARTSYS)
4662 if (req->flags & REQ_F_BUFFER_SELECTED)
4663 cflags = io_put_recv_kbuf(req);
4664 /* fast path, check for non-NULL to avoid function call */
4666 kfree(kmsg->free_iov);
4667 req->flags &= ~REQ_F_NEED_CLEANUP;
4668 if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
4670 __io_req_complete(req, issue_flags, ret, cflags);
4674 static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
4676 struct io_buffer *kbuf;
4677 struct io_sr_msg *sr = &req->sr_msg;
4679 void __user *buf = sr->buf;
4680 struct socket *sock;
4684 int ret, cflags = 0;
4685 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4687 sock = sock_from_file(req->file);
4688 if (unlikely(!sock))
4691 if (req->flags & REQ_F_BUFFER_SELECT) {
4692 kbuf = io_recv_buffer_select(req, !force_nonblock);
4694 return PTR_ERR(kbuf);
4695 buf = u64_to_user_ptr(kbuf->addr);
4698 ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
4702 msg.msg_name = NULL;
4703 msg.msg_control = NULL;
4704 msg.msg_controllen = 0;
4705 msg.msg_namelen = 0;
4706 msg.msg_iocb = NULL;
4709 flags = req->sr_msg.msg_flags;
4711 flags |= MSG_DONTWAIT;
4712 if (flags & MSG_WAITALL)
4713 min_ret = iov_iter_count(&msg.msg_iter);
4715 ret = sock_recvmsg(sock, &msg, flags);
4716 if (force_nonblock && ret == -EAGAIN)
4718 if (ret == -ERESTARTSYS)
4721 if (req->flags & REQ_F_BUFFER_SELECTED)
4722 cflags = io_put_recv_kbuf(req);
4723 if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
4725 __io_req_complete(req, issue_flags, ret, cflags);
4729 static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4731 struct io_accept *accept = &req->accept;
4733 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4735 if (sqe->ioprio || sqe->len || sqe->buf_index)
4738 accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
4739 accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4740 accept->flags = READ_ONCE(sqe->accept_flags);
4741 accept->nofile = rlimit(RLIMIT_NOFILE);
4745 static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
4747 struct io_accept *accept = &req->accept;
4748 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4749 unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
4752 if (req->file->f_flags & O_NONBLOCK)
4753 req->flags |= REQ_F_NOWAIT;
4755 ret = __sys_accept4_file(req->file, file_flags, accept->addr,
4756 accept->addr_len, accept->flags,
4758 if (ret == -EAGAIN && force_nonblock)
4761 if (ret == -ERESTARTSYS)
4765 __io_req_complete(req, issue_flags, ret, 0);
4769 static int io_connect_prep_async(struct io_kiocb *req)
4771 struct io_async_connect *io = req->async_data;
4772 struct io_connect *conn = &req->connect;
4774 return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
4777 static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4779 struct io_connect *conn = &req->connect;
4781 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4783 if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags)
4786 conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
4787 conn->addr_len = READ_ONCE(sqe->addr2);
4791 static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
4793 struct io_async_connect __io, *io;
4794 unsigned file_flags;
4796 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4798 if (req->async_data) {
4799 io = req->async_data;
4801 ret = move_addr_to_kernel(req->connect.addr,
4802 req->connect.addr_len,
4809 file_flags = force_nonblock ? O_NONBLOCK : 0;
4811 ret = __sys_connect_file(req->file, &io->address,
4812 req->connect.addr_len, file_flags);
4813 if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
4814 if (req->async_data)
4816 if (io_alloc_async_data(req)) {
4820 memcpy(req->async_data, &__io, sizeof(__io));
4823 if (ret == -ERESTARTSYS)
4828 __io_req_complete(req, issue_flags, ret, 0);
4831 #else /* !CONFIG_NET */
4832 #define IO_NETOP_FN(op) \
4833 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
4835 return -EOPNOTSUPP; \
4838 #define IO_NETOP_PREP(op) \
4840 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
4842 return -EOPNOTSUPP; \
4845 #define IO_NETOP_PREP_ASYNC(op) \
4847 static int io_##op##_prep_async(struct io_kiocb *req) \
4849 return -EOPNOTSUPP; \
4852 IO_NETOP_PREP_ASYNC(sendmsg);
4853 IO_NETOP_PREP_ASYNC(recvmsg);
4854 IO_NETOP_PREP_ASYNC(connect);
4855 IO_NETOP_PREP(accept);
4858 #endif /* CONFIG_NET */
4860 struct io_poll_table {
4861 struct poll_table_struct pt;
4862 struct io_kiocb *req;
4867 static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll,
4868 __poll_t mask, io_req_tw_func_t func)
4870 /* for instances that support it check for an event match first: */
4871 if (mask && !(mask & poll->events))
4874 trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
4876 list_del_init(&poll->wait.entry);
4879 req->io_task_work.func = func;
4882 * If this fails, then the task is exiting. When a task exits, the
4883 * work gets canceled, so just cancel this request as well instead
4884 * of executing it. We can't safely execute it anyway, as we may not
4885 * have the needed state needed for it anyway.
4887 io_req_task_work_add(req);
4891 static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
4892 __acquires(&req->ctx->completion_lock)
4894 struct io_ring_ctx *ctx = req->ctx;
4896 if (unlikely(req->task->flags & PF_EXITING))
4897 WRITE_ONCE(poll->canceled, true);
4899 if (!req->result && !READ_ONCE(poll->canceled)) {
4900 struct poll_table_struct pt = { ._key = poll->events };
4902 req->result = vfs_poll(req->file, &pt) & poll->events;
4905 spin_lock(&ctx->completion_lock);
4906 if (!req->result && !READ_ONCE(poll->canceled)) {
4907 add_wait_queue(poll->head, &poll->wait);
4914 static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
4916 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
4917 if (req->opcode == IORING_OP_POLL_ADD)
4918 return req->async_data;
4919 return req->apoll->double_poll;
4922 static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
4924 if (req->opcode == IORING_OP_POLL_ADD)
4926 return &req->apoll->poll;
4929 static void io_poll_remove_double(struct io_kiocb *req)
4930 __must_hold(&req->ctx->completion_lock)
4932 struct io_poll_iocb *poll = io_poll_get_double(req);
4934 lockdep_assert_held(&req->ctx->completion_lock);
4936 if (poll && poll->head) {
4937 struct wait_queue_head *head = poll->head;
4939 spin_lock_irq(&head->lock);
4940 list_del_init(&poll->wait.entry);
4941 if (poll->wait.private)
4944 spin_unlock_irq(&head->lock);
4948 static bool io_poll_complete(struct io_kiocb *req, __poll_t mask)
4949 __must_hold(&req->ctx->completion_lock)
4951 struct io_ring_ctx *ctx = req->ctx;
4952 unsigned flags = IORING_CQE_F_MORE;
4955 if (READ_ONCE(req->poll.canceled)) {
4957 req->poll.events |= EPOLLONESHOT;
4959 error = mangle_poll(mask);
4961 if (req->poll.events & EPOLLONESHOT)
4963 if (!io_cqring_fill_event(ctx, req->user_data, error, flags)) {
4964 req->poll.done = true;
4967 if (flags & IORING_CQE_F_MORE)
4970 io_commit_cqring(ctx);
4971 return !(flags & IORING_CQE_F_MORE);
4974 static void io_poll_task_func(struct io_kiocb *req)
4976 struct io_ring_ctx *ctx = req->ctx;
4977 struct io_kiocb *nxt;
4979 if (io_poll_rewait(req, &req->poll)) {
4980 spin_unlock(&ctx->completion_lock);
4984 done = io_poll_complete(req, req->result);
4986 io_poll_remove_double(req);
4987 hash_del(&req->hash_node);
4990 add_wait_queue(req->poll.head, &req->poll.wait);
4992 spin_unlock(&ctx->completion_lock);
4993 io_cqring_ev_posted(ctx);
4996 nxt = io_put_req_find_next(req);
4998 io_req_task_submit(nxt);
5003 static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode,
5004 int sync, void *key)
5006 struct io_kiocb *req = wait->private;
5007 struct io_poll_iocb *poll = io_poll_get_single(req);
5008 __poll_t mask = key_to_poll(key);
5009 unsigned long flags;
5011 /* for instances that support it check for an event match first: */
5012 if (mask && !(mask & poll->events))
5014 if (!(poll->events & EPOLLONESHOT))
5015 return poll->wait.func(&poll->wait, mode, sync, key);
5017 list_del_init(&wait->entry);
5022 spin_lock_irqsave(&poll->head->lock, flags);
5023 done = list_empty(&poll->wait.entry);
5025 list_del_init(&poll->wait.entry);
5026 /* make sure double remove sees this as being gone */
5027 wait->private = NULL;
5028 spin_unlock_irqrestore(&poll->head->lock, flags);
5030 /* use wait func handler, so it matches the rq type */
5031 poll->wait.func(&poll->wait, mode, sync, key);
5038 static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
5039 wait_queue_func_t wake_func)
5043 poll->canceled = false;
5044 #define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
5045 /* mask in events that we always want/need */
5046 poll->events = events | IO_POLL_UNMASK;
5047 INIT_LIST_HEAD(&poll->wait.entry);
5048 init_waitqueue_func_entry(&poll->wait, wake_func);
5051 static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
5052 struct wait_queue_head *head,
5053 struct io_poll_iocb **poll_ptr)
5055 struct io_kiocb *req = pt->req;
5058 * The file being polled uses multiple waitqueues for poll handling
5059 * (e.g. one for read, one for write). Setup a separate io_poll_iocb
5062 if (unlikely(pt->nr_entries)) {
5063 struct io_poll_iocb *poll_one = poll;
5065 /* already have a 2nd entry, fail a third attempt */
5067 pt->error = -EINVAL;
5071 * Can't handle multishot for double wait for now, turn it
5072 * into one-shot mode.
5074 if (!(poll_one->events & EPOLLONESHOT))
5075 poll_one->events |= EPOLLONESHOT;
5076 /* double add on the same waitqueue head, ignore */
5077 if (poll_one->head == head)
5079 poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
5081 pt->error = -ENOMEM;
5084 io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
5086 poll->wait.private = req;
5093 if (poll->events & EPOLLEXCLUSIVE)
5094 add_wait_queue_exclusive(head, &poll->wait);
5096 add_wait_queue(head, &poll->wait);
5099 static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
5100 struct poll_table_struct *p)
5102 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
5103 struct async_poll *apoll = pt->req->apoll;
5105 __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
5108 static void io_async_task_func(struct io_kiocb *req)
5110 struct async_poll *apoll = req->apoll;
5111 struct io_ring_ctx *ctx = req->ctx;
5113 trace_io_uring_task_run(req->ctx, req, req->opcode, req->user_data);
5115 if (io_poll_rewait(req, &apoll->poll)) {
5116 spin_unlock(&ctx->completion_lock);
5120 hash_del(&req->hash_node);
5121 io_poll_remove_double(req);
5122 spin_unlock(&ctx->completion_lock);
5124 if (!READ_ONCE(apoll->poll.canceled))
5125 io_req_task_submit(req);
5127 io_req_complete_failed(req, -ECANCELED);
5130 static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5133 struct io_kiocb *req = wait->private;
5134 struct io_poll_iocb *poll = &req->apoll->poll;
5136 trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data,
5139 return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func);
5142 static void io_poll_req_insert(struct io_kiocb *req)
5144 struct io_ring_ctx *ctx = req->ctx;
5145 struct hlist_head *list;
5147 list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
5148 hlist_add_head(&req->hash_node, list);
5151 static __poll_t __io_arm_poll_handler(struct io_kiocb *req,
5152 struct io_poll_iocb *poll,
5153 struct io_poll_table *ipt, __poll_t mask,
5154 wait_queue_func_t wake_func)
5155 __acquires(&ctx->completion_lock)
5157 struct io_ring_ctx *ctx = req->ctx;
5158 bool cancel = false;
5160 INIT_HLIST_NODE(&req->hash_node);
5161 io_init_poll_iocb(poll, mask, wake_func);
5162 poll->file = req->file;
5163 poll->wait.private = req;
5165 ipt->pt._key = mask;
5168 ipt->nr_entries = 0;
5170 mask = vfs_poll(req->file, &ipt->pt) & poll->events;
5171 if (unlikely(!ipt->nr_entries) && !ipt->error)
5172 ipt->error = -EINVAL;
5174 spin_lock(&ctx->completion_lock);
5175 if (ipt->error || (mask && (poll->events & EPOLLONESHOT)))
5176 io_poll_remove_double(req);
5177 if (likely(poll->head)) {
5178 spin_lock_irq(&poll->head->lock);
5179 if (unlikely(list_empty(&poll->wait.entry))) {
5185 if ((mask && (poll->events & EPOLLONESHOT)) || ipt->error)
5186 list_del_init(&poll->wait.entry);
5188 WRITE_ONCE(poll->canceled, true);
5189 else if (!poll->done) /* actually waiting for an event */
5190 io_poll_req_insert(req);
5191 spin_unlock_irq(&poll->head->lock);
5203 static int io_arm_poll_handler(struct io_kiocb *req)
5205 const struct io_op_def *def = &io_op_defs[req->opcode];
5206 struct io_ring_ctx *ctx = req->ctx;
5207 struct async_poll *apoll;
5208 struct io_poll_table ipt;
5209 __poll_t ret, mask = EPOLLONESHOT | POLLERR | POLLPRI;
5212 if (!req->file || !file_can_poll(req->file))
5213 return IO_APOLL_ABORTED;
5214 if (req->flags & REQ_F_POLLED)
5215 return IO_APOLL_ABORTED;
5216 if (!def->pollin && !def->pollout)
5217 return IO_APOLL_ABORTED;
5221 mask |= POLLIN | POLLRDNORM;
5223 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5224 if ((req->opcode == IORING_OP_RECVMSG) &&
5225 (req->sr_msg.msg_flags & MSG_ERRQUEUE))
5229 mask |= POLLOUT | POLLWRNORM;
5232 /* if we can't nonblock try, then no point in arming a poll handler */
5233 if (!io_file_supports_nowait(req, rw))
5234 return IO_APOLL_ABORTED;
5236 apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
5237 if (unlikely(!apoll))
5238 return IO_APOLL_ABORTED;
5239 apoll->double_poll = NULL;
5241 req->flags |= REQ_F_POLLED;
5242 ipt.pt._qproc = io_async_queue_proc;
5243 io_req_set_refcount(req);
5245 ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask,
5247 spin_unlock(&ctx->completion_lock);
5248 if (ret || ipt.error)
5249 return ret ? IO_APOLL_READY : IO_APOLL_ABORTED;
5251 trace_io_uring_poll_arm(ctx, req, req->opcode, req->user_data,
5252 mask, apoll->poll.events);
5256 static bool __io_poll_remove_one(struct io_kiocb *req,
5257 struct io_poll_iocb *poll, bool do_cancel)
5258 __must_hold(&req->ctx->completion_lock)
5260 bool do_complete = false;
5264 spin_lock_irq(&poll->head->lock);
5266 WRITE_ONCE(poll->canceled, true);
5267 if (!list_empty(&poll->wait.entry)) {
5268 list_del_init(&poll->wait.entry);
5271 spin_unlock_irq(&poll->head->lock);
5272 hash_del(&req->hash_node);
5276 static bool io_poll_remove_one(struct io_kiocb *req)
5277 __must_hold(&req->ctx->completion_lock)
5281 io_poll_remove_double(req);
5282 do_complete = __io_poll_remove_one(req, io_poll_get_single(req), true);
5285 io_cqring_fill_event(req->ctx, req->user_data, -ECANCELED, 0);
5286 io_commit_cqring(req->ctx);
5288 io_put_req_deferred(req);
5294 * Returns true if we found and killed one or more poll requests
5296 static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
5299 struct hlist_node *tmp;
5300 struct io_kiocb *req;
5303 spin_lock(&ctx->completion_lock);
5304 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
5305 struct hlist_head *list;
5307 list = &ctx->cancel_hash[i];
5308 hlist_for_each_entry_safe(req, tmp, list, hash_node) {
5309 if (io_match_task(req, tsk, cancel_all))
5310 posted += io_poll_remove_one(req);
5313 spin_unlock(&ctx->completion_lock);
5316 io_cqring_ev_posted(ctx);
5321 static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, __u64 sqe_addr,
5323 __must_hold(&ctx->completion_lock)
5325 struct hlist_head *list;
5326 struct io_kiocb *req;
5328 list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
5329 hlist_for_each_entry(req, list, hash_node) {
5330 if (sqe_addr != req->user_data)
5332 if (poll_only && req->opcode != IORING_OP_POLL_ADD)
5339 static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr,
5341 __must_hold(&ctx->completion_lock)
5343 struct io_kiocb *req;
5345 req = io_poll_find(ctx, sqe_addr, poll_only);
5348 if (io_poll_remove_one(req))
5354 static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
5359 events = READ_ONCE(sqe->poll32_events);
5361 events = swahw32(events);
5363 if (!(flags & IORING_POLL_ADD_MULTI))
5364 events |= EPOLLONESHOT;
5365 return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
5368 static int io_poll_update_prep(struct io_kiocb *req,
5369 const struct io_uring_sqe *sqe)
5371 struct io_poll_update *upd = &req->poll_update;
5374 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5376 if (sqe->ioprio || sqe->buf_index)
5378 flags = READ_ONCE(sqe->len);
5379 if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA |
5380 IORING_POLL_ADD_MULTI))
5382 /* meaningless without update */
5383 if (flags == IORING_POLL_ADD_MULTI)
5386 upd->old_user_data = READ_ONCE(sqe->addr);
5387 upd->update_events = flags & IORING_POLL_UPDATE_EVENTS;
5388 upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA;
5390 upd->new_user_data = READ_ONCE(sqe->off);
5391 if (!upd->update_user_data && upd->new_user_data)
5393 if (upd->update_events)
5394 upd->events = io_poll_parse_events(sqe, flags);
5395 else if (sqe->poll32_events)
5401 static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5404 struct io_kiocb *req = wait->private;
5405 struct io_poll_iocb *poll = &req->poll;
5407 return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func);
5410 static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
5411 struct poll_table_struct *p)
5413 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
5415 __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
5418 static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5420 struct io_poll_iocb *poll = &req->poll;
5423 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5425 if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->addr)
5427 flags = READ_ONCE(sqe->len);
5428 if (flags & ~IORING_POLL_ADD_MULTI)
5431 io_req_set_refcount(req);
5432 poll->events = io_poll_parse_events(sqe, flags);
5436 static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
5438 struct io_poll_iocb *poll = &req->poll;
5439 struct io_ring_ctx *ctx = req->ctx;
5440 struct io_poll_table ipt;
5443 ipt.pt._qproc = io_poll_queue_proc;
5445 mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,
5448 if (mask) { /* no async, we'd stolen it */
5450 io_poll_complete(req, mask);
5452 spin_unlock(&ctx->completion_lock);
5455 io_cqring_ev_posted(ctx);
5456 if (poll->events & EPOLLONESHOT)
5462 static int io_poll_update(struct io_kiocb *req, unsigned int issue_flags)
5464 struct io_ring_ctx *ctx = req->ctx;
5465 struct io_kiocb *preq;
5469 spin_lock(&ctx->completion_lock);
5470 preq = io_poll_find(ctx, req->poll_update.old_user_data, true);
5476 if (!req->poll_update.update_events && !req->poll_update.update_user_data) {
5478 ret = io_poll_remove_one(preq) ? 0 : -EALREADY;
5483 * Don't allow racy completion with singleshot, as we cannot safely
5484 * update those. For multishot, if we're racing with completion, just
5485 * let completion re-add it.
5487 completing = !__io_poll_remove_one(preq, &preq->poll, false);
5488 if (completing && (preq->poll.events & EPOLLONESHOT)) {
5492 /* we now have a detached poll request. reissue. */
5496 spin_unlock(&ctx->completion_lock);
5498 io_req_complete(req, ret);
5501 /* only mask one event flags, keep behavior flags */
5502 if (req->poll_update.update_events) {
5503 preq->poll.events &= ~0xffff;
5504 preq->poll.events |= req->poll_update.events & 0xffff;
5505 preq->poll.events |= IO_POLL_UNMASK;
5507 if (req->poll_update.update_user_data)
5508 preq->user_data = req->poll_update.new_user_data;
5509 spin_unlock(&ctx->completion_lock);
5511 /* complete update request, we're done with it */
5512 io_req_complete(req, ret);
5515 ret = io_poll_add(preq, issue_flags);
5518 io_req_complete(preq, ret);
5524 static void io_req_task_timeout(struct io_kiocb *req)
5526 struct io_ring_ctx *ctx = req->ctx;
5528 spin_lock(&ctx->completion_lock);
5529 io_cqring_fill_event(ctx, req->user_data, -ETIME, 0);
5530 io_commit_cqring(ctx);
5531 spin_unlock(&ctx->completion_lock);
5533 io_cqring_ev_posted(ctx);
5538 static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
5540 struct io_timeout_data *data = container_of(timer,
5541 struct io_timeout_data, timer);
5542 struct io_kiocb *req = data->req;
5543 struct io_ring_ctx *ctx = req->ctx;
5544 unsigned long flags;
5546 spin_lock_irqsave(&ctx->timeout_lock, flags);
5547 list_del_init(&req->timeout.list);
5548 atomic_set(&req->ctx->cq_timeouts,
5549 atomic_read(&req->ctx->cq_timeouts) + 1);
5550 spin_unlock_irqrestore(&ctx->timeout_lock, flags);
5552 req->io_task_work.func = io_req_task_timeout;
5553 io_req_task_work_add(req);
5554 return HRTIMER_NORESTART;
5557 static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
5559 __must_hold(&ctx->timeout_lock)
5561 struct io_timeout_data *io;
5562 struct io_kiocb *req;
5565 list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
5566 found = user_data == req->user_data;
5571 return ERR_PTR(-ENOENT);
5573 io = req->async_data;
5574 if (hrtimer_try_to_cancel(&io->timer) == -1)
5575 return ERR_PTR(-EALREADY);
5576 list_del_init(&req->timeout.list);
5580 static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
5581 __must_hold(&ctx->timeout_lock)
5583 struct io_kiocb *req = io_timeout_extract(ctx, user_data);
5586 return PTR_ERR(req);
5589 io_cqring_fill_event(ctx, req->user_data, -ECANCELED, 0);
5590 io_put_req_deferred(req);
5594 static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
5595 struct timespec64 *ts, enum hrtimer_mode mode)
5596 __must_hold(&ctx->timeout_lock)
5598 struct io_kiocb *req = io_timeout_extract(ctx, user_data);
5599 struct io_timeout_data *data;
5602 return PTR_ERR(req);
5604 req->timeout.off = 0; /* noseq */
5605 data = req->async_data;
5606 list_add_tail(&req->timeout.list, &ctx->timeout_list);
5607 hrtimer_init(&data->timer, CLOCK_MONOTONIC, mode);
5608 data->timer.function = io_timeout_fn;
5609 hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
5613 static int io_timeout_remove_prep(struct io_kiocb *req,
5614 const struct io_uring_sqe *sqe)
5616 struct io_timeout_rem *tr = &req->timeout_rem;
5618 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5620 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5622 if (sqe->ioprio || sqe->buf_index || sqe->len)
5625 tr->addr = READ_ONCE(sqe->addr);
5626 tr->flags = READ_ONCE(sqe->timeout_flags);
5627 if (tr->flags & IORING_TIMEOUT_UPDATE) {
5628 if (tr->flags & ~(IORING_TIMEOUT_UPDATE|IORING_TIMEOUT_ABS))
5630 if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
5632 } else if (tr->flags) {
5633 /* timeout removal doesn't support flags */
5640 static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
5642 return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
5647 * Remove or update an existing timeout command
5649 static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
5651 struct io_timeout_rem *tr = &req->timeout_rem;
5652 struct io_ring_ctx *ctx = req->ctx;
5655 spin_lock_irq(&ctx->timeout_lock);
5656 if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE))
5657 ret = io_timeout_cancel(ctx, tr->addr);
5659 ret = io_timeout_update(ctx, tr->addr, &tr->ts,
5660 io_translate_timeout_mode(tr->flags));
5661 spin_unlock_irq(&ctx->timeout_lock);
5663 spin_lock(&ctx->completion_lock);
5664 io_cqring_fill_event(ctx, req->user_data, ret, 0);
5665 io_commit_cqring(ctx);
5666 spin_unlock(&ctx->completion_lock);
5667 io_cqring_ev_posted(ctx);
5674 static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
5675 bool is_timeout_link)
5677 struct io_timeout_data *data;
5679 u32 off = READ_ONCE(sqe->off);
5681 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5683 if (sqe->ioprio || sqe->buf_index || sqe->len != 1)
5685 if (off && is_timeout_link)
5687 flags = READ_ONCE(sqe->timeout_flags);
5688 if (flags & ~IORING_TIMEOUT_ABS)
5691 req->timeout.off = off;
5692 if (unlikely(off && !req->ctx->off_timeout_used))
5693 req->ctx->off_timeout_used = true;
5695 if (!req->async_data && io_alloc_async_data(req))
5698 data = req->async_data;
5701 if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
5704 data->mode = io_translate_timeout_mode(flags);
5705 hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode);
5707 if (is_timeout_link) {
5708 struct io_submit_link *link = &req->ctx->submit_state.link;
5712 if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
5714 req->timeout.head = link->last;
5715 link->last->flags |= REQ_F_ARM_LTIMEOUT;
5720 static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
5722 struct io_ring_ctx *ctx = req->ctx;
5723 struct io_timeout_data *data = req->async_data;
5724 struct list_head *entry;
5725 u32 tail, off = req->timeout.off;
5727 spin_lock_irq(&ctx->timeout_lock);
5730 * sqe->off holds how many events that need to occur for this
5731 * timeout event to be satisfied. If it isn't set, then this is
5732 * a pure timeout request, sequence isn't used.
5734 if (io_is_timeout_noseq(req)) {
5735 entry = ctx->timeout_list.prev;
5739 tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
5740 req->timeout.target_seq = tail + off;
5742 /* Update the last seq here in case io_flush_timeouts() hasn't.
5743 * This is safe because ->completion_lock is held, and submissions
5744 * and completions are never mixed in the same ->completion_lock section.
5746 ctx->cq_last_tm_flush = tail;
5749 * Insertion sort, ensuring the first entry in the list is always
5750 * the one we need first.
5752 list_for_each_prev(entry, &ctx->timeout_list) {
5753 struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
5756 if (io_is_timeout_noseq(nxt))
5758 /* nxt.seq is behind @tail, otherwise would've been completed */
5759 if (off >= nxt->timeout.target_seq - tail)
5763 list_add(&req->timeout.list, entry);
5764 data->timer.function = io_timeout_fn;
5765 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
5766 spin_unlock_irq(&ctx->timeout_lock);
5770 struct io_cancel_data {
5771 struct io_ring_ctx *ctx;
5775 static bool io_cancel_cb(struct io_wq_work *work, void *data)
5777 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
5778 struct io_cancel_data *cd = data;
5780 return req->ctx == cd->ctx && req->user_data == cd->user_data;
5783 static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
5784 struct io_ring_ctx *ctx)
5786 struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, };
5787 enum io_wq_cancel cancel_ret;
5790 if (!tctx || !tctx->io_wq)
5793 cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false);
5794 switch (cancel_ret) {
5795 case IO_WQ_CANCEL_OK:
5798 case IO_WQ_CANCEL_RUNNING:
5801 case IO_WQ_CANCEL_NOTFOUND:
5809 static int io_try_cancel_userdata(struct io_kiocb *req, u64 sqe_addr)
5810 __acquires(&req->ctx->completion_lock)
5812 struct io_ring_ctx *ctx = req->ctx;
5815 WARN_ON_ONCE(req->task != current);
5817 ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
5818 spin_lock(&ctx->completion_lock);
5821 spin_lock_irq(&ctx->timeout_lock);
5822 ret = io_timeout_cancel(ctx, sqe_addr);
5823 spin_unlock_irq(&ctx->timeout_lock);
5826 return io_poll_cancel(ctx, sqe_addr, false);
5829 static int io_async_cancel_prep(struct io_kiocb *req,
5830 const struct io_uring_sqe *sqe)
5832 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5834 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5836 if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags)
5839 req->cancel.addr = READ_ONCE(sqe->addr);
5843 static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
5845 struct io_ring_ctx *ctx = req->ctx;
5846 u64 sqe_addr = req->cancel.addr;
5847 struct io_tctx_node *node;
5850 ret = io_try_cancel_userdata(req, sqe_addr);
5853 spin_unlock(&ctx->completion_lock);
5855 /* slow path, try all io-wq's */
5856 io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
5858 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
5859 struct io_uring_task *tctx = node->task->io_uring;
5861 ret = io_async_cancel_one(tctx, req->cancel.addr, ctx);
5865 io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
5867 spin_lock(&ctx->completion_lock);
5869 io_cqring_fill_event(ctx, req->user_data, ret, 0);
5870 io_commit_cqring(ctx);
5871 spin_unlock(&ctx->completion_lock);
5872 io_cqring_ev_posted(ctx);
5880 static int io_rsrc_update_prep(struct io_kiocb *req,
5881 const struct io_uring_sqe *sqe)
5883 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5885 if (sqe->ioprio || sqe->rw_flags)
5888 req->rsrc_update.offset = READ_ONCE(sqe->off);
5889 req->rsrc_update.nr_args = READ_ONCE(sqe->len);
5890 if (!req->rsrc_update.nr_args)
5892 req->rsrc_update.arg = READ_ONCE(sqe->addr);
5896 static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
5898 struct io_ring_ctx *ctx = req->ctx;
5899 struct io_uring_rsrc_update2 up;
5902 if (issue_flags & IO_URING_F_NONBLOCK)
5905 up.offset = req->rsrc_update.offset;
5906 up.data = req->rsrc_update.arg;
5911 mutex_lock(&ctx->uring_lock);
5912 ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
5913 &up, req->rsrc_update.nr_args);
5914 mutex_unlock(&ctx->uring_lock);
5918 __io_req_complete(req, issue_flags, ret, 0);
5922 static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5924 switch (req->opcode) {
5927 case IORING_OP_READV:
5928 case IORING_OP_READ_FIXED:
5929 case IORING_OP_READ:
5930 return io_read_prep(req, sqe);
5931 case IORING_OP_WRITEV:
5932 case IORING_OP_WRITE_FIXED:
5933 case IORING_OP_WRITE:
5934 return io_write_prep(req, sqe);
5935 case IORING_OP_POLL_ADD:
5936 return io_poll_add_prep(req, sqe);
5937 case IORING_OP_POLL_REMOVE:
5938 return io_poll_update_prep(req, sqe);
5939 case IORING_OP_FSYNC:
5940 return io_fsync_prep(req, sqe);
5941 case IORING_OP_SYNC_FILE_RANGE:
5942 return io_sfr_prep(req, sqe);
5943 case IORING_OP_SENDMSG:
5944 case IORING_OP_SEND:
5945 return io_sendmsg_prep(req, sqe);
5946 case IORING_OP_RECVMSG:
5947 case IORING_OP_RECV:
5948 return io_recvmsg_prep(req, sqe);
5949 case IORING_OP_CONNECT:
5950 return io_connect_prep(req, sqe);
5951 case IORING_OP_TIMEOUT:
5952 return io_timeout_prep(req, sqe, false);
5953 case IORING_OP_TIMEOUT_REMOVE:
5954 return io_timeout_remove_prep(req, sqe);
5955 case IORING_OP_ASYNC_CANCEL:
5956 return io_async_cancel_prep(req, sqe);
5957 case IORING_OP_LINK_TIMEOUT:
5958 return io_timeout_prep(req, sqe, true);
5959 case IORING_OP_ACCEPT:
5960 return io_accept_prep(req, sqe);
5961 case IORING_OP_FALLOCATE:
5962 return io_fallocate_prep(req, sqe);
5963 case IORING_OP_OPENAT:
5964 return io_openat_prep(req, sqe);
5965 case IORING_OP_CLOSE:
5966 return io_close_prep(req, sqe);
5967 case IORING_OP_FILES_UPDATE:
5968 return io_rsrc_update_prep(req, sqe);
5969 case IORING_OP_STATX:
5970 return io_statx_prep(req, sqe);
5971 case IORING_OP_FADVISE:
5972 return io_fadvise_prep(req, sqe);
5973 case IORING_OP_MADVISE:
5974 return io_madvise_prep(req, sqe);
5975 case IORING_OP_OPENAT2:
5976 return io_openat2_prep(req, sqe);
5977 case IORING_OP_EPOLL_CTL:
5978 return io_epoll_ctl_prep(req, sqe);
5979 case IORING_OP_SPLICE:
5980 return io_splice_prep(req, sqe);
5981 case IORING_OP_PROVIDE_BUFFERS:
5982 return io_provide_buffers_prep(req, sqe);
5983 case IORING_OP_REMOVE_BUFFERS:
5984 return io_remove_buffers_prep(req, sqe);
5986 return io_tee_prep(req, sqe);
5987 case IORING_OP_SHUTDOWN:
5988 return io_shutdown_prep(req, sqe);
5989 case IORING_OP_RENAMEAT:
5990 return io_renameat_prep(req, sqe);
5991 case IORING_OP_UNLINKAT:
5992 return io_unlinkat_prep(req, sqe);
5995 printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
6000 static int io_req_prep_async(struct io_kiocb *req)
6002 if (!io_op_defs[req->opcode].needs_async_setup)
6004 if (WARN_ON_ONCE(req->async_data))
6006 if (io_alloc_async_data(req))
6009 switch (req->opcode) {
6010 case IORING_OP_READV:
6011 return io_rw_prep_async(req, READ);
6012 case IORING_OP_WRITEV:
6013 return io_rw_prep_async(req, WRITE);
6014 case IORING_OP_SENDMSG:
6015 return io_sendmsg_prep_async(req);
6016 case IORING_OP_RECVMSG:
6017 return io_recvmsg_prep_async(req);
6018 case IORING_OP_CONNECT:
6019 return io_connect_prep_async(req);
6021 printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n",
6026 static u32 io_get_sequence(struct io_kiocb *req)
6028 u32 seq = req->ctx->cached_sq_head;
6030 /* need original cached_sq_head, but it was increased for each req */
6031 io_for_each_link(req, req)
6036 static bool io_drain_req(struct io_kiocb *req)
6038 struct io_kiocb *pos;
6039 struct io_ring_ctx *ctx = req->ctx;
6040 struct io_defer_entry *de;
6045 * If we need to drain a request in the middle of a link, drain the
6046 * head request and the next request/link after the current link.
6047 * Considering sequential execution of links, IOSQE_IO_DRAIN will be
6048 * maintained for every request of our link.
6050 if (ctx->drain_next) {
6051 req->flags |= REQ_F_IO_DRAIN;
6052 ctx->drain_next = false;
6054 /* not interested in head, start from the first linked */
6055 io_for_each_link(pos, req->link) {
6056 if (pos->flags & REQ_F_IO_DRAIN) {
6057 ctx->drain_next = true;
6058 req->flags |= REQ_F_IO_DRAIN;
6063 /* Still need defer if there is pending req in defer list. */
6064 if (likely(list_empty_careful(&ctx->defer_list) &&
6065 !(req->flags & REQ_F_IO_DRAIN))) {
6066 ctx->drain_active = false;
6070 seq = io_get_sequence(req);
6071 /* Still a chance to pass the sequence check */
6072 if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
6075 ret = io_req_prep_async(req);
6078 io_prep_async_link(req);
6079 de = kmalloc(sizeof(*de), GFP_KERNEL);
6083 io_req_complete_failed(req, ret);
6087 spin_lock(&ctx->completion_lock);
6088 if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
6089 spin_unlock(&ctx->completion_lock);
6091 io_queue_async_work(req);
6095 trace_io_uring_defer(ctx, req, req->user_data);
6098 list_add_tail(&de->list, &ctx->defer_list);
6099 spin_unlock(&ctx->completion_lock);
6103 static void io_clean_op(struct io_kiocb *req)
6105 if (req->flags & REQ_F_BUFFER_SELECTED) {
6106 switch (req->opcode) {
6107 case IORING_OP_READV:
6108 case IORING_OP_READ_FIXED:
6109 case IORING_OP_READ:
6110 kfree((void *)(unsigned long)req->rw.addr);
6112 case IORING_OP_RECVMSG:
6113 case IORING_OP_RECV:
6114 kfree(req->sr_msg.kbuf);
6119 if (req->flags & REQ_F_NEED_CLEANUP) {
6120 switch (req->opcode) {
6121 case IORING_OP_READV:
6122 case IORING_OP_READ_FIXED:
6123 case IORING_OP_READ:
6124 case IORING_OP_WRITEV:
6125 case IORING_OP_WRITE_FIXED:
6126 case IORING_OP_WRITE: {
6127 struct io_async_rw *io = req->async_data;
6129 kfree(io->free_iovec);
6132 case IORING_OP_RECVMSG:
6133 case IORING_OP_SENDMSG: {
6134 struct io_async_msghdr *io = req->async_data;
6136 kfree(io->free_iov);
6139 case IORING_OP_SPLICE:
6141 if (!(req->splice.flags & SPLICE_F_FD_IN_FIXED))
6142 io_put_file(req->splice.file_in);
6144 case IORING_OP_OPENAT:
6145 case IORING_OP_OPENAT2:
6146 if (req->open.filename)
6147 putname(req->open.filename);
6149 case IORING_OP_RENAMEAT:
6150 putname(req->rename.oldpath);
6151 putname(req->rename.newpath);
6153 case IORING_OP_UNLINKAT:
6154 putname(req->unlink.filename);
6158 if ((req->flags & REQ_F_POLLED) && req->apoll) {
6159 kfree(req->apoll->double_poll);
6163 if (req->flags & REQ_F_INFLIGHT) {
6164 struct io_uring_task *tctx = req->task->io_uring;
6166 atomic_dec(&tctx->inflight_tracked);
6168 if (req->flags & REQ_F_CREDS)
6169 put_cred(req->creds);
6171 req->flags &= ~IO_REQ_CLEAN_FLAGS;
6174 static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
6176 struct io_ring_ctx *ctx = req->ctx;
6177 const struct cred *creds = NULL;
6180 if ((req->flags & REQ_F_CREDS) && req->creds != current_cred())
6181 creds = override_creds(req->creds);
6183 switch (req->opcode) {
6185 ret = io_nop(req, issue_flags);
6187 case IORING_OP_READV:
6188 case IORING_OP_READ_FIXED:
6189 case IORING_OP_READ:
6190 ret = io_read(req, issue_flags);
6192 case IORING_OP_WRITEV:
6193 case IORING_OP_WRITE_FIXED:
6194 case IORING_OP_WRITE:
6195 ret = io_write(req, issue_flags);
6197 case IORING_OP_FSYNC:
6198 ret = io_fsync(req, issue_flags);
6200 case IORING_OP_POLL_ADD:
6201 ret = io_poll_add(req, issue_flags);
6203 case IORING_OP_POLL_REMOVE:
6204 ret = io_poll_update(req, issue_flags);
6206 case IORING_OP_SYNC_FILE_RANGE:
6207 ret = io_sync_file_range(req, issue_flags);
6209 case IORING_OP_SENDMSG:
6210 ret = io_sendmsg(req, issue_flags);
6212 case IORING_OP_SEND:
6213 ret = io_send(req, issue_flags);
6215 case IORING_OP_RECVMSG:
6216 ret = io_recvmsg(req, issue_flags);
6218 case IORING_OP_RECV:
6219 ret = io_recv(req, issue_flags);
6221 case IORING_OP_TIMEOUT:
6222 ret = io_timeout(req, issue_flags);
6224 case IORING_OP_TIMEOUT_REMOVE:
6225 ret = io_timeout_remove(req, issue_flags);
6227 case IORING_OP_ACCEPT:
6228 ret = io_accept(req, issue_flags);
6230 case IORING_OP_CONNECT:
6231 ret = io_connect(req, issue_flags);
6233 case IORING_OP_ASYNC_CANCEL:
6234 ret = io_async_cancel(req, issue_flags);
6236 case IORING_OP_FALLOCATE:
6237 ret = io_fallocate(req, issue_flags);
6239 case IORING_OP_OPENAT:
6240 ret = io_openat(req, issue_flags);
6242 case IORING_OP_CLOSE:
6243 ret = io_close(req, issue_flags);
6245 case IORING_OP_FILES_UPDATE:
6246 ret = io_files_update(req, issue_flags);
6248 case IORING_OP_STATX:
6249 ret = io_statx(req, issue_flags);
6251 case IORING_OP_FADVISE:
6252 ret = io_fadvise(req, issue_flags);
6254 case IORING_OP_MADVISE:
6255 ret = io_madvise(req, issue_flags);
6257 case IORING_OP_OPENAT2:
6258 ret = io_openat2(req, issue_flags);
6260 case IORING_OP_EPOLL_CTL:
6261 ret = io_epoll_ctl(req, issue_flags);
6263 case IORING_OP_SPLICE:
6264 ret = io_splice(req, issue_flags);
6266 case IORING_OP_PROVIDE_BUFFERS:
6267 ret = io_provide_buffers(req, issue_flags);
6269 case IORING_OP_REMOVE_BUFFERS:
6270 ret = io_remove_buffers(req, issue_flags);
6273 ret = io_tee(req, issue_flags);
6275 case IORING_OP_SHUTDOWN:
6276 ret = io_shutdown(req, issue_flags);
6278 case IORING_OP_RENAMEAT:
6279 ret = io_renameat(req, issue_flags);
6281 case IORING_OP_UNLINKAT:
6282 ret = io_unlinkat(req, issue_flags);
6290 revert_creds(creds);
6293 /* If the op doesn't have a file, we're not polling for it */
6294 if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file)
6295 io_iopoll_req_issued(req);
6300 static struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
6302 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
6304 req = io_put_req_find_next(req);
6305 return req ? &req->work : NULL;
6308 static void io_wq_submit_work(struct io_wq_work *work)
6310 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
6311 struct io_kiocb *timeout;
6314 /* one will be dropped by ->io_free_work() after returning to io-wq */
6315 if (!(req->flags & REQ_F_REFCOUNT))
6316 __io_req_set_refcount(req, 2);
6320 timeout = io_prep_linked_timeout(req);
6322 io_queue_linked_timeout(timeout);
6324 if (work->flags & IO_WQ_WORK_CANCEL)
6329 ret = io_issue_sqe(req, 0);
6331 * We can get EAGAIN for polled IO even though we're
6332 * forcing a sync submission from here, since we can't
6333 * wait for request slots on the block side.
6341 /* avoid locking problems by failing it from a clean context */
6343 io_req_task_queue_fail(req, ret);
6346 static inline struct io_fixed_file *io_fixed_file_slot(struct io_file_table *table,
6349 return &table->files[i];
6352 static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
6355 struct io_fixed_file *slot = io_fixed_file_slot(&ctx->file_table, index);
6357 return (struct file *) (slot->file_ptr & FFS_MASK);
6360 static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file)
6362 unsigned long file_ptr = (unsigned long) file;
6364 if (__io_file_supports_nowait(file, READ))
6365 file_ptr |= FFS_ASYNC_READ;
6366 if (__io_file_supports_nowait(file, WRITE))
6367 file_ptr |= FFS_ASYNC_WRITE;
6368 if (S_ISREG(file_inode(file)->i_mode))
6369 file_ptr |= FFS_ISREG;
6370 file_slot->file_ptr = file_ptr;
6373 static inline struct file *io_file_get_fixed(struct io_ring_ctx *ctx,
6374 struct io_kiocb *req, int fd)
6377 unsigned long file_ptr;
6379 if (unlikely((unsigned int)fd >= ctx->nr_user_files))
6381 fd = array_index_nospec(fd, ctx->nr_user_files);
6382 file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr;
6383 file = (struct file *) (file_ptr & FFS_MASK);
6384 file_ptr &= ~FFS_MASK;
6385 /* mask in overlapping REQ_F and FFS bits */
6386 req->flags |= (file_ptr << REQ_F_NOWAIT_READ_BIT);
6387 io_req_set_rsrc_node(req);
6391 static struct file *io_file_get_normal(struct io_ring_ctx *ctx,
6392 struct io_kiocb *req, int fd)
6394 struct file *file = fget(fd);
6396 trace_io_uring_file_get(ctx, fd);
6398 /* we don't allow fixed io_uring files */
6399 if (file && unlikely(file->f_op == &io_uring_fops))
6400 io_req_track_inflight(req);
6404 static inline struct file *io_file_get(struct io_ring_ctx *ctx,
6405 struct io_kiocb *req, int fd, bool fixed)
6408 return io_file_get_fixed(ctx, req, fd);
6410 return io_file_get_normal(ctx, req, fd);
6413 static void io_req_task_link_timeout(struct io_kiocb *req)
6415 struct io_kiocb *prev = req->timeout.prev;
6416 struct io_ring_ctx *ctx = req->ctx;
6420 ret = io_try_cancel_userdata(req, prev->user_data);
6423 io_cqring_fill_event(ctx, req->user_data, ret, 0);
6424 io_commit_cqring(ctx);
6425 spin_unlock(&ctx->completion_lock);
6426 io_cqring_ev_posted(ctx);
6431 io_req_complete_post(req, -ETIME, 0);
6435 static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
6437 struct io_timeout_data *data = container_of(timer,
6438 struct io_timeout_data, timer);
6439 struct io_kiocb *prev, *req = data->req;
6440 struct io_ring_ctx *ctx = req->ctx;
6441 unsigned long flags;
6443 spin_lock_irqsave(&ctx->timeout_lock, flags);
6444 prev = req->timeout.head;
6445 req->timeout.head = NULL;
6448 * We don't expect the list to be empty, that will only happen if we
6449 * race with the completion of the linked work.
6452 io_remove_next_linked(prev);
6453 if (!req_ref_inc_not_zero(prev))
6456 req->timeout.prev = prev;
6457 spin_unlock_irqrestore(&ctx->timeout_lock, flags);
6459 req->io_task_work.func = io_req_task_link_timeout;
6460 io_req_task_work_add(req);
6461 return HRTIMER_NORESTART;
6464 static void io_queue_linked_timeout(struct io_kiocb *req)
6466 struct io_ring_ctx *ctx = req->ctx;
6468 spin_lock_irq(&ctx->timeout_lock);
6470 * If the back reference is NULL, then our linked request finished
6471 * before we got a chance to setup the timer
6473 if (req->timeout.head) {
6474 struct io_timeout_data *data = req->async_data;
6476 data->timer.function = io_link_timeout_fn;
6477 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
6480 spin_unlock_irq(&ctx->timeout_lock);
6481 /* drop submission reference */
6485 static void __io_queue_sqe(struct io_kiocb *req)
6486 __must_hold(&req->ctx->uring_lock)
6488 struct io_kiocb *linked_timeout;
6492 ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
6495 * We async punt it if the file wasn't marked NOWAIT, or if the file
6496 * doesn't support non-blocking read/write attempts
6499 if (req->flags & REQ_F_COMPLETE_INLINE) {
6500 struct io_ring_ctx *ctx = req->ctx;
6501 struct io_submit_state *state = &ctx->submit_state;
6503 state->compl_reqs[state->compl_nr++] = req;
6504 if (state->compl_nr == ARRAY_SIZE(state->compl_reqs))
6505 io_submit_flush_completions(ctx);
6509 linked_timeout = io_prep_linked_timeout(req);
6511 io_queue_linked_timeout(linked_timeout);
6512 } else if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
6513 linked_timeout = io_prep_linked_timeout(req);
6515 switch (io_arm_poll_handler(req)) {
6516 case IO_APOLL_READY:
6518 io_unprep_linked_timeout(req);
6520 case IO_APOLL_ABORTED:
6522 * Queued up for async execution, worker will release
6523 * submit reference when the iocb is actually submitted.
6525 io_queue_async_work(req);
6530 io_queue_linked_timeout(linked_timeout);
6532 io_req_complete_failed(req, ret);
6536 static inline void io_queue_sqe(struct io_kiocb *req)
6537 __must_hold(&req->ctx->uring_lock)
6539 if (unlikely(req->ctx->drain_active) && io_drain_req(req))
6542 if (likely(!(req->flags & REQ_F_FORCE_ASYNC))) {
6543 __io_queue_sqe(req);
6545 int ret = io_req_prep_async(req);
6548 io_req_complete_failed(req, ret);
6550 io_queue_async_work(req);
6555 * Check SQE restrictions (opcode and flags).
6557 * Returns 'true' if SQE is allowed, 'false' otherwise.
6559 static inline bool io_check_restriction(struct io_ring_ctx *ctx,
6560 struct io_kiocb *req,
6561 unsigned int sqe_flags)
6563 if (likely(!ctx->restricted))
6566 if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
6569 if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
6570 ctx->restrictions.sqe_flags_required)
6573 if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
6574 ctx->restrictions.sqe_flags_required))
6580 static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
6581 const struct io_uring_sqe *sqe)
6582 __must_hold(&ctx->uring_lock)
6584 struct io_submit_state *state;
6585 unsigned int sqe_flags;
6586 int personality, ret = 0;
6588 /* req is partially pre-initialised, see io_preinit_req() */
6589 req->opcode = READ_ONCE(sqe->opcode);
6590 /* same numerical values with corresponding REQ_F_*, safe to copy */
6591 req->flags = sqe_flags = READ_ONCE(sqe->flags);
6592 req->user_data = READ_ONCE(sqe->user_data);
6594 req->fixed_rsrc_refs = NULL;
6595 req->task = current;
6597 /* enforce forwards compatibility on users */
6598 if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))
6600 if (unlikely(req->opcode >= IORING_OP_LAST))
6602 if (!io_check_restriction(ctx, req, sqe_flags))
6605 if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
6606 !io_op_defs[req->opcode].buffer_select)
6608 if (unlikely(sqe_flags & IOSQE_IO_DRAIN))
6609 ctx->drain_active = true;
6611 personality = READ_ONCE(sqe->personality);
6613 req->creds = xa_load(&ctx->personalities, personality);
6616 get_cred(req->creds);
6617 req->flags |= REQ_F_CREDS;
6619 state = &ctx->submit_state;
6622 * Plug now if we have more than 1 IO left after this, and the target
6623 * is potentially a read/write to block based storage.
6625 if (!state->plug_started && state->ios_left > 1 &&
6626 io_op_defs[req->opcode].plug) {
6627 blk_start_plug(&state->plug);
6628 state->plug_started = true;
6631 if (io_op_defs[req->opcode].needs_file) {
6632 req->file = io_file_get(ctx, req, READ_ONCE(sqe->fd),
6633 (sqe_flags & IOSQE_FIXED_FILE));
6634 if (unlikely(!req->file))
6642 static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
6643 const struct io_uring_sqe *sqe)
6644 __must_hold(&ctx->uring_lock)
6646 struct io_submit_link *link = &ctx->submit_state.link;
6649 ret = io_init_req(ctx, req, sqe);
6650 if (unlikely(ret)) {
6653 /* fail even hard links since we don't submit */
6654 req_set_fail(link->head);
6655 io_req_complete_failed(link->head, -ECANCELED);
6658 io_req_complete_failed(req, ret);
6662 ret = io_req_prep(req, sqe);
6666 /* don't need @sqe from now on */
6667 trace_io_uring_submit_sqe(ctx, req, req->opcode, req->user_data,
6669 ctx->flags & IORING_SETUP_SQPOLL);
6672 * If we already have a head request, queue this one for async
6673 * submittal once the head completes. If we don't have a head but
6674 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
6675 * submitted sync once the chain is complete. If none of those
6676 * conditions are true (normal request), then just queue it.
6679 struct io_kiocb *head = link->head;
6681 ret = io_req_prep_async(req);
6684 trace_io_uring_link(ctx, req, head);
6685 link->last->link = req;
6688 /* last request of a link, enqueue the link */
6689 if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
6694 if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
6706 * Batched submission is done, ensure local IO is flushed out.
6708 static void io_submit_state_end(struct io_submit_state *state,
6709 struct io_ring_ctx *ctx)
6711 if (state->link.head)
6712 io_queue_sqe(state->link.head);
6713 if (state->compl_nr)
6714 io_submit_flush_completions(ctx);
6715 if (state->plug_started)
6716 blk_finish_plug(&state->plug);
6720 * Start submission side cache.
6722 static void io_submit_state_start(struct io_submit_state *state,
6723 unsigned int max_ios)
6725 state->plug_started = false;
6726 state->ios_left = max_ios;
6727 /* set only head, no need to init link_last in advance */
6728 state->link.head = NULL;
6731 static void io_commit_sqring(struct io_ring_ctx *ctx)
6733 struct io_rings *rings = ctx->rings;
6736 * Ensure any loads from the SQEs are done at this point,
6737 * since once we write the new head, the application could
6738 * write new data to them.
6740 smp_store_release(&rings->sq.head, ctx->cached_sq_head);
6744 * Fetch an sqe, if one is available. Note this returns a pointer to memory
6745 * that is mapped by userspace. This means that care needs to be taken to
6746 * ensure that reads are stable, as we cannot rely on userspace always
6747 * being a good citizen. If members of the sqe are validated and then later
6748 * used, it's important that those reads are done through READ_ONCE() to
6749 * prevent a re-load down the line.
6751 static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
6753 unsigned head, mask = ctx->sq_entries - 1;
6754 unsigned sq_idx = ctx->cached_sq_head++ & mask;
6757 * The cached sq head (or cq tail) serves two purposes:
6759 * 1) allows us to batch the cost of updating the user visible
6761 * 2) allows the kernel side to track the head on its own, even
6762 * though the application is the one updating it.
6764 head = READ_ONCE(ctx->sq_array[sq_idx]);
6765 if (likely(head < ctx->sq_entries))
6766 return &ctx->sq_sqes[head];
6768 /* drop invalid entries */
6770 WRITE_ONCE(ctx->rings->sq_dropped,
6771 READ_ONCE(ctx->rings->sq_dropped) + 1);
6775 static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
6776 __must_hold(&ctx->uring_lock)
6778 struct io_uring_task *tctx;
6781 /* make sure SQ entry isn't read before tail */
6782 nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
6783 if (!percpu_ref_tryget_many(&ctx->refs, nr))
6786 tctx = current->io_uring;
6787 tctx->cached_refs -= nr;
6788 if (unlikely(tctx->cached_refs < 0)) {
6789 unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR;
6791 percpu_counter_add(&tctx->inflight, refill);
6792 refcount_add(refill, ¤t->usage);
6793 tctx->cached_refs += refill;
6795 io_submit_state_start(&ctx->submit_state, nr);
6797 while (submitted < nr) {
6798 const struct io_uring_sqe *sqe;
6799 struct io_kiocb *req;
6801 req = io_alloc_req(ctx);
6802 if (unlikely(!req)) {
6804 submitted = -EAGAIN;
6807 sqe = io_get_sqe(ctx);
6808 if (unlikely(!sqe)) {
6809 kmem_cache_free(req_cachep, req);
6812 /* will complete beyond this point, count as submitted */
6814 if (io_submit_sqe(ctx, req, sqe))
6818 if (unlikely(submitted != nr)) {
6819 int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
6820 int unused = nr - ref_used;
6822 current->io_uring->cached_refs += unused;
6823 percpu_ref_put_many(&ctx->refs, unused);
6826 io_submit_state_end(&ctx->submit_state, ctx);
6827 /* Commit SQ ring head once we've consumed and submitted all SQEs */
6828 io_commit_sqring(ctx);
6833 static inline bool io_sqd_events_pending(struct io_sq_data *sqd)
6835 return READ_ONCE(sqd->state);
6838 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
6840 /* Tell userspace we may need a wakeup call */
6841 spin_lock(&ctx->completion_lock);
6842 WRITE_ONCE(ctx->rings->sq_flags,
6843 ctx->rings->sq_flags | IORING_SQ_NEED_WAKEUP);
6844 spin_unlock(&ctx->completion_lock);
6847 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
6849 spin_lock(&ctx->completion_lock);
6850 WRITE_ONCE(ctx->rings->sq_flags,
6851 ctx->rings->sq_flags & ~IORING_SQ_NEED_WAKEUP);
6852 spin_unlock(&ctx->completion_lock);
6855 static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
6857 unsigned int to_submit;
6860 to_submit = io_sqring_entries(ctx);
6861 /* if we're handling multiple rings, cap submit size for fairness */
6862 if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE)
6863 to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;
6865 if (!list_empty(&ctx->iopoll_list) || to_submit) {
6866 unsigned nr_events = 0;
6867 const struct cred *creds = NULL;
6869 if (ctx->sq_creds != current_cred())
6870 creds = override_creds(ctx->sq_creds);
6872 mutex_lock(&ctx->uring_lock);
6873 if (!list_empty(&ctx->iopoll_list))
6874 io_do_iopoll(ctx, &nr_events, 0);
6877 * Don't submit if refs are dying, good for io_uring_register(),
6878 * but also it is relied upon by io_ring_exit_work()
6880 if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
6881 !(ctx->flags & IORING_SETUP_R_DISABLED))
6882 ret = io_submit_sqes(ctx, to_submit);
6883 mutex_unlock(&ctx->uring_lock);
6885 if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
6886 wake_up(&ctx->sqo_sq_wait);
6888 revert_creds(creds);
6894 static void io_sqd_update_thread_idle(struct io_sq_data *sqd)
6896 struct io_ring_ctx *ctx;
6897 unsigned sq_thread_idle = 0;
6899 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6900 sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle);
6901 sqd->sq_thread_idle = sq_thread_idle;
6904 static bool io_sqd_handle_event(struct io_sq_data *sqd)
6906 bool did_sig = false;
6907 struct ksignal ksig;
6909 if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
6910 signal_pending(current)) {
6911 mutex_unlock(&sqd->lock);
6912 if (signal_pending(current))
6913 did_sig = get_signal(&ksig);
6915 mutex_lock(&sqd->lock);
6917 return did_sig || test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
6920 static int io_sq_thread(void *data)
6922 struct io_sq_data *sqd = data;
6923 struct io_ring_ctx *ctx;
6924 unsigned long timeout = 0;
6925 char buf[TASK_COMM_LEN];
6928 snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
6929 set_task_comm(current, buf);
6931 if (sqd->sq_cpu != -1)
6932 set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
6934 set_cpus_allowed_ptr(current, cpu_online_mask);
6935 current->flags |= PF_NO_SETAFFINITY;
6937 mutex_lock(&sqd->lock);
6939 bool cap_entries, sqt_spin = false;
6941 if (io_sqd_events_pending(sqd) || signal_pending(current)) {
6942 if (io_sqd_handle_event(sqd))
6944 timeout = jiffies + sqd->sq_thread_idle;
6947 cap_entries = !list_is_singular(&sqd->ctx_list);
6948 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
6949 int ret = __io_sq_thread(ctx, cap_entries);
6951 if (!sqt_spin && (ret > 0 || !list_empty(&ctx->iopoll_list)))
6954 if (io_run_task_work())
6957 if (sqt_spin || !time_after(jiffies, timeout)) {
6960 timeout = jiffies + sqd->sq_thread_idle;
6964 prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
6965 if (!io_sqd_events_pending(sqd) && !current->task_works) {
6966 bool needs_sched = true;
6968 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
6969 io_ring_set_wakeup_flag(ctx);
6971 if ((ctx->flags & IORING_SETUP_IOPOLL) &&
6972 !list_empty_careful(&ctx->iopoll_list)) {
6973 needs_sched = false;
6976 if (io_sqring_entries(ctx)) {
6977 needs_sched = false;
6983 mutex_unlock(&sqd->lock);
6985 mutex_lock(&sqd->lock);
6987 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6988 io_ring_clear_wakeup_flag(ctx);
6991 finish_wait(&sqd->wait, &wait);
6992 timeout = jiffies + sqd->sq_thread_idle;
6995 io_uring_cancel_generic(true, sqd);
6997 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
6998 io_ring_set_wakeup_flag(ctx);
7000 mutex_unlock(&sqd->lock);
7002 complete(&sqd->exited);
7006 struct io_wait_queue {
7007 struct wait_queue_entry wq;
7008 struct io_ring_ctx *ctx;
7010 unsigned nr_timeouts;
7013 static inline bool io_should_wake(struct io_wait_queue *iowq)
7015 struct io_ring_ctx *ctx = iowq->ctx;
7016 int dist = ctx->cached_cq_tail - (int) iowq->cq_tail;
7019 * Wake up if we have enough events, or if a timeout occurred since we
7020 * started waiting. For timeouts, we always want to return to userspace,
7021 * regardless of event count.
7023 return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
7026 static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
7027 int wake_flags, void *key)
7029 struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
7033 * Cannot safely flush overflowed CQEs from here, ensure we wake up
7034 * the task, and the next invocation will do it.
7036 if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->check_cq_overflow))
7037 return autoremove_wake_function(curr, mode, wake_flags, key);
7041 static int io_run_task_work_sig(void)
7043 if (io_run_task_work())
7045 if (!signal_pending(current))
7047 if (test_thread_flag(TIF_NOTIFY_SIGNAL))
7048 return -ERESTARTSYS;
7052 /* when returns >0, the caller should retry */
7053 static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
7054 struct io_wait_queue *iowq,
7055 signed long *timeout)
7059 /* make sure we run task_work before checking for signals */
7060 ret = io_run_task_work_sig();
7061 if (ret || io_should_wake(iowq))
7063 /* let the caller flush overflows, retry */
7064 if (test_bit(0, &ctx->check_cq_overflow))
7067 *timeout = schedule_timeout(*timeout);
7068 return !*timeout ? -ETIME : 1;
7072 * Wait until events become available, if we don't already have some. The
7073 * application must reap them itself, as they reside on the shared cq ring.
7075 static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
7076 const sigset_t __user *sig, size_t sigsz,
7077 struct __kernel_timespec __user *uts)
7079 struct io_wait_queue iowq;
7080 struct io_rings *rings = ctx->rings;
7081 signed long timeout = MAX_SCHEDULE_TIMEOUT;
7085 io_cqring_overflow_flush(ctx);
7086 if (io_cqring_events(ctx) >= min_events)
7088 if (!io_run_task_work())
7093 #ifdef CONFIG_COMPAT
7094 if (in_compat_syscall())
7095 ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
7099 ret = set_user_sigmask(sig, sigsz);
7106 struct timespec64 ts;
7108 if (get_timespec64(&ts, uts))
7110 timeout = timespec64_to_jiffies(&ts);
7113 init_waitqueue_func_entry(&iowq.wq, io_wake_function);
7114 iowq.wq.private = current;
7115 INIT_LIST_HEAD(&iowq.wq.entry);
7117 iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
7118 iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events;
7120 trace_io_uring_cqring_wait(ctx, min_events);
7122 /* if we can't even flush overflow, don't wait for more */
7123 if (!io_cqring_overflow_flush(ctx)) {
7127 prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq,
7128 TASK_INTERRUPTIBLE);
7129 ret = io_cqring_wait_schedule(ctx, &iowq, &timeout);
7130 finish_wait(&ctx->cq_wait, &iowq.wq);
7134 restore_saved_sigmask_unless(ret == -EINTR);
7136 return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
7139 static void io_free_page_table(void **table, size_t size)
7141 unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
7143 for (i = 0; i < nr_tables; i++)
7148 static void **io_alloc_page_table(size_t size)
7150 unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
7151 size_t init_size = size;
7154 table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL);
7158 for (i = 0; i < nr_tables; i++) {
7159 unsigned int this_size = min_t(size_t, size, PAGE_SIZE);
7161 table[i] = kzalloc(this_size, GFP_KERNEL);
7163 io_free_page_table(table, init_size);
7171 static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node)
7173 percpu_ref_exit(&ref_node->refs);
7177 static void io_rsrc_node_ref_zero(struct percpu_ref *ref)
7179 struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs);
7180 struct io_ring_ctx *ctx = node->rsrc_data->ctx;
7181 unsigned long flags;
7182 bool first_add = false;
7184 spin_lock_irqsave(&ctx->rsrc_ref_lock, flags);
7187 while (!list_empty(&ctx->rsrc_ref_list)) {
7188 node = list_first_entry(&ctx->rsrc_ref_list,
7189 struct io_rsrc_node, node);
7190 /* recycle ref nodes in order */
7193 list_del(&node->node);
7194 first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist);
7196 spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags);
7199 mod_delayed_work(system_wq, &ctx->rsrc_put_work, HZ);
7202 static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx)
7204 struct io_rsrc_node *ref_node;
7206 ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
7210 if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
7215 INIT_LIST_HEAD(&ref_node->node);
7216 INIT_LIST_HEAD(&ref_node->rsrc_list);
7217 ref_node->done = false;
7221 static void io_rsrc_node_switch(struct io_ring_ctx *ctx,
7222 struct io_rsrc_data *data_to_kill)
7224 WARN_ON_ONCE(!ctx->rsrc_backup_node);
7225 WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node);
7228 struct io_rsrc_node *rsrc_node = ctx->rsrc_node;
7230 rsrc_node->rsrc_data = data_to_kill;
7231 spin_lock_irq(&ctx->rsrc_ref_lock);
7232 list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list);
7233 spin_unlock_irq(&ctx->rsrc_ref_lock);
7235 atomic_inc(&data_to_kill->refs);
7236 percpu_ref_kill(&rsrc_node->refs);
7237 ctx->rsrc_node = NULL;
7240 if (!ctx->rsrc_node) {
7241 ctx->rsrc_node = ctx->rsrc_backup_node;
7242 ctx->rsrc_backup_node = NULL;
7246 static int io_rsrc_node_switch_start(struct io_ring_ctx *ctx)
7248 if (ctx->rsrc_backup_node)
7250 ctx->rsrc_backup_node = io_rsrc_node_alloc(ctx);
7251 return ctx->rsrc_backup_node ? 0 : -ENOMEM;
7254 static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, struct io_ring_ctx *ctx)
7258 /* As we may drop ->uring_lock, other task may have started quiesce */
7262 data->quiesce = true;
7264 ret = io_rsrc_node_switch_start(ctx);
7267 io_rsrc_node_switch(ctx, data);
7269 /* kill initial ref, already quiesced if zero */
7270 if (atomic_dec_and_test(&data->refs))
7272 mutex_unlock(&ctx->uring_lock);
7273 flush_delayed_work(&ctx->rsrc_put_work);
7274 ret = wait_for_completion_interruptible(&data->done);
7276 mutex_lock(&ctx->uring_lock);
7280 atomic_inc(&data->refs);
7281 /* wait for all works potentially completing data->done */
7282 flush_delayed_work(&ctx->rsrc_put_work);
7283 reinit_completion(&data->done);
7285 ret = io_run_task_work_sig();
7286 mutex_lock(&ctx->uring_lock);
7288 data->quiesce = false;
7293 static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
7295 unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
7296 unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
7298 return &data->tags[table_idx][off];
7301 static void io_rsrc_data_free(struct io_rsrc_data *data)
7303 size_t size = data->nr * sizeof(data->tags[0][0]);
7306 io_free_page_table((void **)data->tags, size);
7310 static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put,
7311 u64 __user *utags, unsigned nr,
7312 struct io_rsrc_data **pdata)
7314 struct io_rsrc_data *data;
7318 data = kzalloc(sizeof(*data), GFP_KERNEL);
7321 data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0]));
7329 data->do_put = do_put;
7332 for (i = 0; i < nr; i++) {
7333 u64 *tag_slot = io_get_tag_slot(data, i);
7335 if (copy_from_user(tag_slot, &utags[i],
7341 atomic_set(&data->refs, 1);
7342 init_completion(&data->done);
7346 io_rsrc_data_free(data);
7350 static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
7352 table->files = kvcalloc(nr_files, sizeof(table->files[0]), GFP_KERNEL);
7353 return !!table->files;
7356 static void io_free_file_tables(struct io_file_table *table)
7358 kvfree(table->files);
7359 table->files = NULL;
7362 static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
7364 #if defined(CONFIG_UNIX)
7365 if (ctx->ring_sock) {
7366 struct sock *sock = ctx->ring_sock->sk;
7367 struct sk_buff *skb;
7369 while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
7375 for (i = 0; i < ctx->nr_user_files; i++) {
7378 file = io_file_from_index(ctx, i);
7383 io_free_file_tables(&ctx->file_table);
7384 io_rsrc_data_free(ctx->file_data);
7385 ctx->file_data = NULL;
7386 ctx->nr_user_files = 0;
7389 static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
7393 if (!ctx->file_data)
7395 ret = io_rsrc_ref_quiesce(ctx->file_data, ctx);
7397 __io_sqe_files_unregister(ctx);
7401 static void io_sq_thread_unpark(struct io_sq_data *sqd)
7402 __releases(&sqd->lock)
7404 WARN_ON_ONCE(sqd->thread == current);
7407 * Do the dance but not conditional clear_bit() because it'd race with
7408 * other threads incrementing park_pending and setting the bit.
7410 clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7411 if (atomic_dec_return(&sqd->park_pending))
7412 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7413 mutex_unlock(&sqd->lock);
7416 static void io_sq_thread_park(struct io_sq_data *sqd)
7417 __acquires(&sqd->lock)
7419 WARN_ON_ONCE(sqd->thread == current);
7421 atomic_inc(&sqd->park_pending);
7422 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7423 mutex_lock(&sqd->lock);
7425 wake_up_process(sqd->thread);
7428 static void io_sq_thread_stop(struct io_sq_data *sqd)
7430 WARN_ON_ONCE(sqd->thread == current);
7431 WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state));
7433 set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
7434 mutex_lock(&sqd->lock);
7436 wake_up_process(sqd->thread);
7437 mutex_unlock(&sqd->lock);
7438 wait_for_completion(&sqd->exited);
7441 static void io_put_sq_data(struct io_sq_data *sqd)
7443 if (refcount_dec_and_test(&sqd->refs)) {
7444 WARN_ON_ONCE(atomic_read(&sqd->park_pending));
7446 io_sq_thread_stop(sqd);
7451 static void io_sq_thread_finish(struct io_ring_ctx *ctx)
7453 struct io_sq_data *sqd = ctx->sq_data;
7456 io_sq_thread_park(sqd);
7457 list_del_init(&ctx->sqd_list);
7458 io_sqd_update_thread_idle(sqd);
7459 io_sq_thread_unpark(sqd);
7461 io_put_sq_data(sqd);
7462 ctx->sq_data = NULL;
7466 static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
7468 struct io_ring_ctx *ctx_attach;
7469 struct io_sq_data *sqd;
7472 f = fdget(p->wq_fd);
7474 return ERR_PTR(-ENXIO);
7475 if (f.file->f_op != &io_uring_fops) {
7477 return ERR_PTR(-EINVAL);
7480 ctx_attach = f.file->private_data;
7481 sqd = ctx_attach->sq_data;
7484 return ERR_PTR(-EINVAL);
7486 if (sqd->task_tgid != current->tgid) {
7488 return ERR_PTR(-EPERM);
7491 refcount_inc(&sqd->refs);
7496 static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
7499 struct io_sq_data *sqd;
7502 if (p->flags & IORING_SETUP_ATTACH_WQ) {
7503 sqd = io_attach_sq_data(p);
7508 /* fall through for EPERM case, setup new sqd/task */
7509 if (PTR_ERR(sqd) != -EPERM)
7513 sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
7515 return ERR_PTR(-ENOMEM);
7517 atomic_set(&sqd->park_pending, 0);
7518 refcount_set(&sqd->refs, 1);
7519 INIT_LIST_HEAD(&sqd->ctx_list);
7520 mutex_init(&sqd->lock);
7521 init_waitqueue_head(&sqd->wait);
7522 init_completion(&sqd->exited);
7526 #if defined(CONFIG_UNIX)
7528 * Ensure the UNIX gc is aware of our file set, so we are certain that
7529 * the io_uring can be safely unregistered on process exit, even if we have
7530 * loops in the file referencing.
7532 static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
7534 struct sock *sk = ctx->ring_sock->sk;
7535 struct scm_fp_list *fpl;
7536 struct sk_buff *skb;
7539 fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
7543 skb = alloc_skb(0, GFP_KERNEL);
7552 fpl->user = get_uid(current_user());
7553 for (i = 0; i < nr; i++) {
7554 struct file *file = io_file_from_index(ctx, i + offset);
7558 fpl->fp[nr_files] = get_file(file);
7559 unix_inflight(fpl->user, fpl->fp[nr_files]);
7564 fpl->max = SCM_MAX_FD;
7565 fpl->count = nr_files;
7566 UNIXCB(skb).fp = fpl;
7567 skb->destructor = unix_destruct_scm;
7568 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
7569 skb_queue_head(&sk->sk_receive_queue, skb);
7571 for (i = 0; i < nr_files; i++)
7582 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
7583 * causes regular reference counting to break down. We rely on the UNIX
7584 * garbage collection to take care of this problem for us.
7586 static int io_sqe_files_scm(struct io_ring_ctx *ctx)
7588 unsigned left, total;
7592 left = ctx->nr_user_files;
7594 unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
7596 ret = __io_sqe_files_scm(ctx, this_files, total);
7600 total += this_files;
7606 while (total < ctx->nr_user_files) {
7607 struct file *file = io_file_from_index(ctx, total);
7617 static int io_sqe_files_scm(struct io_ring_ctx *ctx)
7623 static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
7625 struct file *file = prsrc->file;
7626 #if defined(CONFIG_UNIX)
7627 struct sock *sock = ctx->ring_sock->sk;
7628 struct sk_buff_head list, *head = &sock->sk_receive_queue;
7629 struct sk_buff *skb;
7632 __skb_queue_head_init(&list);
7635 * Find the skb that holds this file in its SCM_RIGHTS. When found,
7636 * remove this entry and rearrange the file array.
7638 skb = skb_dequeue(head);
7640 struct scm_fp_list *fp;
7642 fp = UNIXCB(skb).fp;
7643 for (i = 0; i < fp->count; i++) {
7646 if (fp->fp[i] != file)
7649 unix_notinflight(fp->user, fp->fp[i]);
7650 left = fp->count - 1 - i;
7652 memmove(&fp->fp[i], &fp->fp[i + 1],
7653 left * sizeof(struct file *));
7660 __skb_queue_tail(&list, skb);
7670 __skb_queue_tail(&list, skb);
7672 skb = skb_dequeue(head);
7675 if (skb_peek(&list)) {
7676 spin_lock_irq(&head->lock);
7677 while ((skb = __skb_dequeue(&list)) != NULL)
7678 __skb_queue_tail(head, skb);
7679 spin_unlock_irq(&head->lock);
7686 static void __io_rsrc_put_work(struct io_rsrc_node *ref_node)
7688 struct io_rsrc_data *rsrc_data = ref_node->rsrc_data;
7689 struct io_ring_ctx *ctx = rsrc_data->ctx;
7690 struct io_rsrc_put *prsrc, *tmp;
7692 list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
7693 list_del(&prsrc->list);
7696 bool lock_ring = ctx->flags & IORING_SETUP_IOPOLL;
7698 io_ring_submit_lock(ctx, lock_ring);
7699 spin_lock(&ctx->completion_lock);
7700 io_cqring_fill_event(ctx, prsrc->tag, 0, 0);
7702 io_commit_cqring(ctx);
7703 spin_unlock(&ctx->completion_lock);
7704 io_cqring_ev_posted(ctx);
7705 io_ring_submit_unlock(ctx, lock_ring);
7708 rsrc_data->do_put(ctx, prsrc);
7712 io_rsrc_node_destroy(ref_node);
7713 if (atomic_dec_and_test(&rsrc_data->refs))
7714 complete(&rsrc_data->done);
7717 static void io_rsrc_put_work(struct work_struct *work)
7719 struct io_ring_ctx *ctx;
7720 struct llist_node *node;
7722 ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
7723 node = llist_del_all(&ctx->rsrc_put_llist);
7726 struct io_rsrc_node *ref_node;
7727 struct llist_node *next = node->next;
7729 ref_node = llist_entry(node, struct io_rsrc_node, llist);
7730 __io_rsrc_put_work(ref_node);
7735 static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
7736 unsigned nr_args, u64 __user *tags)
7738 __s32 __user *fds = (__s32 __user *) arg;
7747 if (nr_args > IORING_MAX_FIXED_FILES)
7749 ret = io_rsrc_node_switch_start(ctx);
7752 ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args,
7758 if (!io_alloc_file_tables(&ctx->file_table, nr_args))
7761 for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
7762 if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
7766 /* allow sparse sets */
7769 if (unlikely(*io_get_tag_slot(ctx->file_data, i)))
7776 if (unlikely(!file))
7780 * Don't allow io_uring instances to be registered. If UNIX
7781 * isn't enabled, then this causes a reference cycle and this
7782 * instance can never get freed. If UNIX is enabled we'll
7783 * handle it just fine, but there's still no point in allowing
7784 * a ring fd as it doesn't support regular read/write anyway.
7786 if (file->f_op == &io_uring_fops) {
7790 io_fixed_file_set(io_fixed_file_slot(&ctx->file_table, i), file);
7793 ret = io_sqe_files_scm(ctx);
7795 __io_sqe_files_unregister(ctx);
7799 io_rsrc_node_switch(ctx, NULL);
7802 for (i = 0; i < ctx->nr_user_files; i++) {
7803 file = io_file_from_index(ctx, i);
7807 io_free_file_tables(&ctx->file_table);
7808 ctx->nr_user_files = 0;
7810 io_rsrc_data_free(ctx->file_data);
7811 ctx->file_data = NULL;
7815 static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
7818 #if defined(CONFIG_UNIX)
7819 struct sock *sock = ctx->ring_sock->sk;
7820 struct sk_buff_head *head = &sock->sk_receive_queue;
7821 struct sk_buff *skb;
7824 * See if we can merge this file into an existing skb SCM_RIGHTS
7825 * file set. If there's no room, fall back to allocating a new skb
7826 * and filling it in.
7828 spin_lock_irq(&head->lock);
7829 skb = skb_peek(head);
7831 struct scm_fp_list *fpl = UNIXCB(skb).fp;
7833 if (fpl->count < SCM_MAX_FD) {
7834 __skb_unlink(skb, head);
7835 spin_unlock_irq(&head->lock);
7836 fpl->fp[fpl->count] = get_file(file);
7837 unix_inflight(fpl->user, fpl->fp[fpl->count]);
7839 spin_lock_irq(&head->lock);
7840 __skb_queue_head(head, skb);
7845 spin_unlock_irq(&head->lock);
7852 return __io_sqe_files_scm(ctx, 1, index);
7858 static int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
7859 struct io_rsrc_node *node, void *rsrc)
7861 struct io_rsrc_put *prsrc;
7863 prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
7867 prsrc->tag = *io_get_tag_slot(data, idx);
7869 list_add(&prsrc->list, &node->rsrc_list);
7873 static int __io_sqe_files_update(struct io_ring_ctx *ctx,
7874 struct io_uring_rsrc_update2 *up,
7877 u64 __user *tags = u64_to_user_ptr(up->tags);
7878 __s32 __user *fds = u64_to_user_ptr(up->data);
7879 struct io_rsrc_data *data = ctx->file_data;
7880 struct io_fixed_file *file_slot;
7884 bool needs_switch = false;
7886 if (!ctx->file_data)
7888 if (up->offset + nr_args > ctx->nr_user_files)
7891 for (done = 0; done < nr_args; done++) {
7894 if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) ||
7895 copy_from_user(&fd, &fds[done], sizeof(fd))) {
7899 if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) {
7903 if (fd == IORING_REGISTER_FILES_SKIP)
7906 i = array_index_nospec(up->offset + done, ctx->nr_user_files);
7907 file_slot = io_fixed_file_slot(&ctx->file_table, i);
7909 if (file_slot->file_ptr) {
7910 file = (struct file *)(file_slot->file_ptr & FFS_MASK);
7911 err = io_queue_rsrc_removal(data, up->offset + done,
7912 ctx->rsrc_node, file);
7915 file_slot->file_ptr = 0;
7916 needs_switch = true;
7925 * Don't allow io_uring instances to be registered. If
7926 * UNIX isn't enabled, then this causes a reference
7927 * cycle and this instance can never get freed. If UNIX
7928 * is enabled we'll handle it just fine, but there's
7929 * still no point in allowing a ring fd as it doesn't
7930 * support regular read/write anyway.
7932 if (file->f_op == &io_uring_fops) {
7937 *io_get_tag_slot(data, up->offset + done) = tag;
7938 io_fixed_file_set(file_slot, file);
7939 err = io_sqe_file_register(ctx, file, i);
7941 file_slot->file_ptr = 0;
7949 io_rsrc_node_switch(ctx, data);
7950 return done ? done : err;
7953 static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
7954 struct task_struct *task)
7956 struct io_wq_hash *hash;
7957 struct io_wq_data data;
7958 unsigned int concurrency;
7960 mutex_lock(&ctx->uring_lock);
7961 hash = ctx->hash_map;
7963 hash = kzalloc(sizeof(*hash), GFP_KERNEL);
7965 mutex_unlock(&ctx->uring_lock);
7966 return ERR_PTR(-ENOMEM);
7968 refcount_set(&hash->refs, 1);
7969 init_waitqueue_head(&hash->wait);
7970 ctx->hash_map = hash;
7972 mutex_unlock(&ctx->uring_lock);
7976 data.free_work = io_wq_free_work;
7977 data.do_work = io_wq_submit_work;
7979 /* Do QD, or 4 * CPUS, whatever is smallest */
7980 concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
7982 return io_wq_create(concurrency, &data);
7985 static int io_uring_alloc_task_context(struct task_struct *task,
7986 struct io_ring_ctx *ctx)
7988 struct io_uring_task *tctx;
7991 tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
7992 if (unlikely(!tctx))
7995 ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
7996 if (unlikely(ret)) {
8001 tctx->io_wq = io_init_wq_offload(ctx, task);
8002 if (IS_ERR(tctx->io_wq)) {
8003 ret = PTR_ERR(tctx->io_wq);
8004 percpu_counter_destroy(&tctx->inflight);
8010 init_waitqueue_head(&tctx->wait);
8011 atomic_set(&tctx->in_idle, 0);
8012 atomic_set(&tctx->inflight_tracked, 0);
8013 task->io_uring = tctx;
8014 spin_lock_init(&tctx->task_lock);
8015 INIT_WQ_LIST(&tctx->task_list);
8016 init_task_work(&tctx->task_work, tctx_task_work);
8020 void __io_uring_free(struct task_struct *tsk)
8022 struct io_uring_task *tctx = tsk->io_uring;
8024 WARN_ON_ONCE(!xa_empty(&tctx->xa));
8025 WARN_ON_ONCE(tctx->io_wq);
8026 WARN_ON_ONCE(tctx->cached_refs);
8028 percpu_counter_destroy(&tctx->inflight);
8030 tsk->io_uring = NULL;
8033 static int io_sq_offload_create(struct io_ring_ctx *ctx,
8034 struct io_uring_params *p)
8038 /* Retain compatibility with failing for an invalid attach attempt */
8039 if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
8040 IORING_SETUP_ATTACH_WQ) {
8043 f = fdget(p->wq_fd);
8046 if (f.file->f_op != &io_uring_fops) {
8052 if (ctx->flags & IORING_SETUP_SQPOLL) {
8053 struct task_struct *tsk;
8054 struct io_sq_data *sqd;
8057 sqd = io_get_sq_data(p, &attached);
8063 ctx->sq_creds = get_current_cred();
8065 ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
8066 if (!ctx->sq_thread_idle)
8067 ctx->sq_thread_idle = HZ;
8069 io_sq_thread_park(sqd);
8070 list_add(&ctx->sqd_list, &sqd->ctx_list);
8071 io_sqd_update_thread_idle(sqd);
8072 /* don't attach to a dying SQPOLL thread, would be racy */
8073 ret = (attached && !sqd->thread) ? -ENXIO : 0;
8074 io_sq_thread_unpark(sqd);
8081 if (p->flags & IORING_SETUP_SQ_AFF) {
8082 int cpu = p->sq_thread_cpu;
8085 if (cpu >= nr_cpu_ids || !cpu_online(cpu))
8092 sqd->task_pid = current->pid;
8093 sqd->task_tgid = current->tgid;
8094 tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
8101 ret = io_uring_alloc_task_context(tsk, ctx);
8102 wake_up_new_task(tsk);
8105 } else if (p->flags & IORING_SETUP_SQ_AFF) {
8106 /* Can't have SQ_AFF without SQPOLL */
8113 complete(&ctx->sq_data->exited);
8115 io_sq_thread_finish(ctx);
8119 static inline void __io_unaccount_mem(struct user_struct *user,
8120 unsigned long nr_pages)
8122 atomic_long_sub(nr_pages, &user->locked_vm);
8125 static inline int __io_account_mem(struct user_struct *user,
8126 unsigned long nr_pages)
8128 unsigned long page_limit, cur_pages, new_pages;
8130 /* Don't allow more pages than we can safely lock */
8131 page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
8134 cur_pages = atomic_long_read(&user->locked_vm);
8135 new_pages = cur_pages + nr_pages;
8136 if (new_pages > page_limit)
8138 } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
8139 new_pages) != cur_pages);
8144 static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
8147 __io_unaccount_mem(ctx->user, nr_pages);
8149 if (ctx->mm_account)
8150 atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
8153 static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
8158 ret = __io_account_mem(ctx->user, nr_pages);
8163 if (ctx->mm_account)
8164 atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
8169 static void io_mem_free(void *ptr)
8176 page = virt_to_head_page(ptr);
8177 if (put_page_testzero(page))
8178 free_compound_page(page);
8181 static void *io_mem_alloc(size_t size)
8183 gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP |
8184 __GFP_NORETRY | __GFP_ACCOUNT;
8186 return (void *) __get_free_pages(gfp_flags, get_order(size));
8189 static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
8192 struct io_rings *rings;
8193 size_t off, sq_array_size;
8195 off = struct_size(rings, cqes, cq_entries);
8196 if (off == SIZE_MAX)
8200 off = ALIGN(off, SMP_CACHE_BYTES);
8208 sq_array_size = array_size(sizeof(u32), sq_entries);
8209 if (sq_array_size == SIZE_MAX)
8212 if (check_add_overflow(off, sq_array_size, &off))
8218 static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot)
8220 struct io_mapped_ubuf *imu = *slot;
8223 if (imu != ctx->dummy_ubuf) {
8224 for (i = 0; i < imu->nr_bvecs; i++)
8225 unpin_user_page(imu->bvec[i].bv_page);
8226 if (imu->acct_pages)
8227 io_unaccount_mem(ctx, imu->acct_pages);
8233 static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
8235 io_buffer_unmap(ctx, &prsrc->buf);
8239 static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
8243 for (i = 0; i < ctx->nr_user_bufs; i++)
8244 io_buffer_unmap(ctx, &ctx->user_bufs[i]);
8245 kfree(ctx->user_bufs);
8246 io_rsrc_data_free(ctx->buf_data);
8247 ctx->user_bufs = NULL;
8248 ctx->buf_data = NULL;
8249 ctx->nr_user_bufs = 0;
8252 static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
8259 ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx);
8261 __io_sqe_buffers_unregister(ctx);
8265 static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
8266 void __user *arg, unsigned index)
8268 struct iovec __user *src;
8270 #ifdef CONFIG_COMPAT
8272 struct compat_iovec __user *ciovs;
8273 struct compat_iovec ciov;
8275 ciovs = (struct compat_iovec __user *) arg;
8276 if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
8279 dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
8280 dst->iov_len = ciov.iov_len;
8284 src = (struct iovec __user *) arg;
8285 if (copy_from_user(dst, &src[index], sizeof(*dst)))
8291 * Not super efficient, but this is just a registration time. And we do cache
8292 * the last compound head, so generally we'll only do a full search if we don't
8295 * We check if the given compound head page has already been accounted, to
8296 * avoid double accounting it. This allows us to account the full size of the
8297 * page, not just the constituent pages of a huge page.
8299 static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
8300 int nr_pages, struct page *hpage)
8304 /* check current page array */
8305 for (i = 0; i < nr_pages; i++) {
8306 if (!PageCompound(pages[i]))
8308 if (compound_head(pages[i]) == hpage)
8312 /* check previously registered pages */
8313 for (i = 0; i < ctx->nr_user_bufs; i++) {
8314 struct io_mapped_ubuf *imu = ctx->user_bufs[i];
8316 for (j = 0; j < imu->nr_bvecs; j++) {
8317 if (!PageCompound(imu->bvec[j].bv_page))
8319 if (compound_head(imu->bvec[j].bv_page) == hpage)
8327 static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
8328 int nr_pages, struct io_mapped_ubuf *imu,
8329 struct page **last_hpage)
8333 imu->acct_pages = 0;
8334 for (i = 0; i < nr_pages; i++) {
8335 if (!PageCompound(pages[i])) {
8340 hpage = compound_head(pages[i]);
8341 if (hpage == *last_hpage)
8343 *last_hpage = hpage;
8344 if (headpage_already_acct(ctx, pages, i, hpage))
8346 imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
8350 if (!imu->acct_pages)
8353 ret = io_account_mem(ctx, imu->acct_pages);
8355 imu->acct_pages = 0;
8359 static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
8360 struct io_mapped_ubuf **pimu,
8361 struct page **last_hpage)
8363 struct io_mapped_ubuf *imu = NULL;
8364 struct vm_area_struct **vmas = NULL;
8365 struct page **pages = NULL;
8366 unsigned long off, start, end, ubuf;
8368 int ret, pret, nr_pages, i;
8370 if (!iov->iov_base) {
8371 *pimu = ctx->dummy_ubuf;
8375 ubuf = (unsigned long) iov->iov_base;
8376 end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
8377 start = ubuf >> PAGE_SHIFT;
8378 nr_pages = end - start;
8383 pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
8387 vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
8392 imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL);
8397 mmap_read_lock(current->mm);
8398 pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
8400 if (pret == nr_pages) {
8401 /* don't support file backed memory */
8402 for (i = 0; i < nr_pages; i++) {
8403 struct vm_area_struct *vma = vmas[i];
8405 if (vma_is_shmem(vma))
8408 !is_file_hugepages(vma->vm_file)) {
8414 ret = pret < 0 ? pret : -EFAULT;
8416 mmap_read_unlock(current->mm);
8419 * if we did partial map, or found file backed vmas,
8420 * release any pages we did get
8423 unpin_user_pages(pages, pret);
8427 ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage);
8429 unpin_user_pages(pages, pret);
8433 off = ubuf & ~PAGE_MASK;
8434 size = iov->iov_len;
8435 for (i = 0; i < nr_pages; i++) {
8438 vec_len = min_t(size_t, size, PAGE_SIZE - off);
8439 imu->bvec[i].bv_page = pages[i];
8440 imu->bvec[i].bv_len = vec_len;
8441 imu->bvec[i].bv_offset = off;
8445 /* store original address for later verification */
8447 imu->ubuf_end = ubuf + iov->iov_len;
8448 imu->nr_bvecs = nr_pages;
8459 static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
8461 ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL);
8462 return ctx->user_bufs ? 0 : -ENOMEM;
8465 static int io_buffer_validate(struct iovec *iov)
8467 unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1);
8470 * Don't impose further limits on the size and buffer
8471 * constraints here, we'll -EINVAL later when IO is
8472 * submitted if they are wrong.
8475 return iov->iov_len ? -EFAULT : 0;
8479 /* arbitrary limit, but we need something */
8480 if (iov->iov_len > SZ_1G)
8483 if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp))
8489 static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
8490 unsigned int nr_args, u64 __user *tags)
8492 struct page *last_hpage = NULL;
8493 struct io_rsrc_data *data;
8499 if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS)
8501 ret = io_rsrc_node_switch_start(ctx);
8504 ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data);
8507 ret = io_buffers_map_alloc(ctx, nr_args);
8509 io_rsrc_data_free(data);
8513 for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) {
8514 ret = io_copy_iov(ctx, &iov, arg, i);
8517 ret = io_buffer_validate(&iov);
8520 if (!iov.iov_base && *io_get_tag_slot(data, i)) {
8525 ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i],
8531 WARN_ON_ONCE(ctx->buf_data);
8533 ctx->buf_data = data;
8535 __io_sqe_buffers_unregister(ctx);
8537 io_rsrc_node_switch(ctx, NULL);
8541 static int __io_sqe_buffers_update(struct io_ring_ctx *ctx,
8542 struct io_uring_rsrc_update2 *up,
8543 unsigned int nr_args)
8545 u64 __user *tags = u64_to_user_ptr(up->tags);
8546 struct iovec iov, __user *iovs = u64_to_user_ptr(up->data);
8547 struct page *last_hpage = NULL;
8548 bool needs_switch = false;
8554 if (up->offset + nr_args > ctx->nr_user_bufs)
8557 for (done = 0; done < nr_args; done++) {
8558 struct io_mapped_ubuf *imu;
8559 int offset = up->offset + done;
8562 err = io_copy_iov(ctx, &iov, iovs, done);
8565 if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) {
8569 err = io_buffer_validate(&iov);
8572 if (!iov.iov_base && tag) {
8576 err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage);
8580 i = array_index_nospec(offset, ctx->nr_user_bufs);
8581 if (ctx->user_bufs[i] != ctx->dummy_ubuf) {
8582 err = io_queue_rsrc_removal(ctx->buf_data, offset,
8583 ctx->rsrc_node, ctx->user_bufs[i]);
8584 if (unlikely(err)) {
8585 io_buffer_unmap(ctx, &imu);
8588 ctx->user_bufs[i] = NULL;
8589 needs_switch = true;
8592 ctx->user_bufs[i] = imu;
8593 *io_get_tag_slot(ctx->buf_data, offset) = tag;
8597 io_rsrc_node_switch(ctx, ctx->buf_data);
8598 return done ? done : err;
8601 static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
8603 __s32 __user *fds = arg;
8609 if (copy_from_user(&fd, fds, sizeof(*fds)))
8612 ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
8613 if (IS_ERR(ctx->cq_ev_fd)) {
8614 int ret = PTR_ERR(ctx->cq_ev_fd);
8616 ctx->cq_ev_fd = NULL;
8623 static int io_eventfd_unregister(struct io_ring_ctx *ctx)
8625 if (ctx->cq_ev_fd) {
8626 eventfd_ctx_put(ctx->cq_ev_fd);
8627 ctx->cq_ev_fd = NULL;
8634 static void io_destroy_buffers(struct io_ring_ctx *ctx)
8636 struct io_buffer *buf;
8637 unsigned long index;
8639 xa_for_each(&ctx->io_buffers, index, buf)
8640 __io_remove_buffers(ctx, buf, index, -1U);
8643 static void io_req_cache_free(struct list_head *list)
8645 struct io_kiocb *req, *nxt;
8647 list_for_each_entry_safe(req, nxt, list, inflight_entry) {
8648 list_del(&req->inflight_entry);
8649 kmem_cache_free(req_cachep, req);
8653 static void io_req_caches_free(struct io_ring_ctx *ctx)
8655 struct io_submit_state *state = &ctx->submit_state;
8657 mutex_lock(&ctx->uring_lock);
8659 if (state->free_reqs) {
8660 kmem_cache_free_bulk(req_cachep, state->free_reqs, state->reqs);
8661 state->free_reqs = 0;
8664 io_flush_cached_locked_reqs(ctx, state);
8665 io_req_cache_free(&state->free_list);
8666 mutex_unlock(&ctx->uring_lock);
8669 static void io_wait_rsrc_data(struct io_rsrc_data *data)
8671 if (data && !atomic_dec_and_test(&data->refs))
8672 wait_for_completion(&data->done);
8675 static void io_ring_ctx_free(struct io_ring_ctx *ctx)
8677 io_sq_thread_finish(ctx);
8679 if (ctx->mm_account) {
8680 mmdrop(ctx->mm_account);
8681 ctx->mm_account = NULL;
8684 /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */
8685 io_wait_rsrc_data(ctx->buf_data);
8686 io_wait_rsrc_data(ctx->file_data);
8688 mutex_lock(&ctx->uring_lock);
8690 __io_sqe_buffers_unregister(ctx);
8692 __io_sqe_files_unregister(ctx);
8694 __io_cqring_overflow_flush(ctx, true);
8695 mutex_unlock(&ctx->uring_lock);
8696 io_eventfd_unregister(ctx);
8697 io_destroy_buffers(ctx);
8699 put_cred(ctx->sq_creds);
8701 /* there are no registered resources left, nobody uses it */
8703 io_rsrc_node_destroy(ctx->rsrc_node);
8704 if (ctx->rsrc_backup_node)
8705 io_rsrc_node_destroy(ctx->rsrc_backup_node);
8706 flush_delayed_work(&ctx->rsrc_put_work);
8708 WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list));
8709 WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist));
8711 #if defined(CONFIG_UNIX)
8712 if (ctx->ring_sock) {
8713 ctx->ring_sock->file = NULL; /* so that iput() is called */
8714 sock_release(ctx->ring_sock);
8718 io_mem_free(ctx->rings);
8719 io_mem_free(ctx->sq_sqes);
8721 percpu_ref_exit(&ctx->refs);
8722 free_uid(ctx->user);
8723 io_req_caches_free(ctx);
8725 io_wq_put_hash(ctx->hash_map);
8726 kfree(ctx->cancel_hash);
8727 kfree(ctx->dummy_ubuf);
8731 static __poll_t io_uring_poll(struct file *file, poll_table *wait)
8733 struct io_ring_ctx *ctx = file->private_data;
8736 poll_wait(file, &ctx->poll_wait, wait);
8738 * synchronizes with barrier from wq_has_sleeper call in
8742 if (!io_sqring_full(ctx))
8743 mask |= EPOLLOUT | EPOLLWRNORM;
8746 * Don't flush cqring overflow list here, just do a simple check.
8747 * Otherwise there could possible be ABBA deadlock:
8750 * lock(&ctx->uring_lock);
8752 * lock(&ctx->uring_lock);
8755 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
8756 * pushs them to do the flush.
8758 if (io_cqring_events(ctx) || test_bit(0, &ctx->check_cq_overflow))
8759 mask |= EPOLLIN | EPOLLRDNORM;
8764 static int io_uring_fasync(int fd, struct file *file, int on)
8766 struct io_ring_ctx *ctx = file->private_data;
8768 return fasync_helper(fd, file, on, &ctx->cq_fasync);
8771 static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
8773 const struct cred *creds;
8775 creds = xa_erase(&ctx->personalities, id);
8784 struct io_tctx_exit {
8785 struct callback_head task_work;
8786 struct completion completion;
8787 struct io_ring_ctx *ctx;
8790 static void io_tctx_exit_cb(struct callback_head *cb)
8792 struct io_uring_task *tctx = current->io_uring;
8793 struct io_tctx_exit *work;
8795 work = container_of(cb, struct io_tctx_exit, task_work);
8797 * When @in_idle, we're in cancellation and it's racy to remove the
8798 * node. It'll be removed by the end of cancellation, just ignore it.
8800 if (!atomic_read(&tctx->in_idle))
8801 io_uring_del_tctx_node((unsigned long)work->ctx);
8802 complete(&work->completion);
8805 static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
8807 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8809 return req->ctx == data;
8812 static void io_ring_exit_work(struct work_struct *work)
8814 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
8815 unsigned long timeout = jiffies + HZ * 60 * 5;
8816 unsigned long interval = HZ / 20;
8817 struct io_tctx_exit exit;
8818 struct io_tctx_node *node;
8822 * If we're doing polled IO and end up having requests being
8823 * submitted async (out-of-line), then completions can come in while
8824 * we're waiting for refs to drop. We need to reap these manually,
8825 * as nobody else will be looking for them.
8828 io_uring_try_cancel_requests(ctx, NULL, true);
8830 struct io_sq_data *sqd = ctx->sq_data;
8831 struct task_struct *tsk;
8833 io_sq_thread_park(sqd);
8835 if (tsk && tsk->io_uring && tsk->io_uring->io_wq)
8836 io_wq_cancel_cb(tsk->io_uring->io_wq,
8837 io_cancel_ctx_cb, ctx, true);
8838 io_sq_thread_unpark(sqd);
8841 if (WARN_ON_ONCE(time_after(jiffies, timeout))) {
8842 /* there is little hope left, don't run it too often */
8845 } while (!wait_for_completion_timeout(&ctx->ref_comp, interval));
8847 init_completion(&exit.completion);
8848 init_task_work(&exit.task_work, io_tctx_exit_cb);
8851 * Some may use context even when all refs and requests have been put,
8852 * and they are free to do so while still holding uring_lock or
8853 * completion_lock, see io_req_task_submit(). Apart from other work,
8854 * this lock/unlock section also waits them to finish.
8856 mutex_lock(&ctx->uring_lock);
8857 while (!list_empty(&ctx->tctx_list)) {
8858 WARN_ON_ONCE(time_after(jiffies, timeout));
8860 node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
8862 /* don't spin on a single task if cancellation failed */
8863 list_rotate_left(&ctx->tctx_list);
8864 ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
8865 if (WARN_ON_ONCE(ret))
8867 wake_up_process(node->task);
8869 mutex_unlock(&ctx->uring_lock);
8870 wait_for_completion(&exit.completion);
8871 mutex_lock(&ctx->uring_lock);
8873 mutex_unlock(&ctx->uring_lock);
8874 spin_lock(&ctx->completion_lock);
8875 spin_unlock(&ctx->completion_lock);
8877 io_ring_ctx_free(ctx);
8880 /* Returns true if we found and killed one or more timeouts */
8881 static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
8884 struct io_kiocb *req, *tmp;
8887 spin_lock(&ctx->completion_lock);
8888 spin_lock_irq(&ctx->timeout_lock);
8889 list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
8890 if (io_match_task(req, tsk, cancel_all)) {
8891 io_kill_timeout(req, -ECANCELED);
8895 spin_unlock_irq(&ctx->timeout_lock);
8897 io_commit_cqring(ctx);
8898 spin_unlock(&ctx->completion_lock);
8900 io_cqring_ev_posted(ctx);
8901 return canceled != 0;
8904 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
8906 unsigned long index;
8907 struct creds *creds;
8909 mutex_lock(&ctx->uring_lock);
8910 percpu_ref_kill(&ctx->refs);
8912 __io_cqring_overflow_flush(ctx, true);
8913 xa_for_each(&ctx->personalities, index, creds)
8914 io_unregister_personality(ctx, index);
8915 mutex_unlock(&ctx->uring_lock);
8917 io_kill_timeouts(ctx, NULL, true);
8918 io_poll_remove_all(ctx, NULL, true);
8920 /* if we failed setting up the ctx, we might not have any rings */
8921 io_iopoll_try_reap_events(ctx);
8923 INIT_WORK(&ctx->exit_work, io_ring_exit_work);
8925 * Use system_unbound_wq to avoid spawning tons of event kworkers
8926 * if we're exiting a ton of rings at the same time. It just adds
8927 * noise and overhead, there's no discernable change in runtime
8928 * over using system_wq.
8930 queue_work(system_unbound_wq, &ctx->exit_work);
8933 static int io_uring_release(struct inode *inode, struct file *file)
8935 struct io_ring_ctx *ctx = file->private_data;
8937 file->private_data = NULL;
8938 io_ring_ctx_wait_and_kill(ctx);
8942 struct io_task_cancel {
8943 struct task_struct *task;
8947 static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
8949 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8950 struct io_task_cancel *cancel = data;
8953 if (!cancel->all && (req->flags & REQ_F_LINK_TIMEOUT)) {
8954 struct io_ring_ctx *ctx = req->ctx;
8956 /* protect against races with linked timeouts */
8957 spin_lock(&ctx->completion_lock);
8958 ret = io_match_task(req, cancel->task, cancel->all);
8959 spin_unlock(&ctx->completion_lock);
8961 ret = io_match_task(req, cancel->task, cancel->all);
8966 static bool io_cancel_defer_files(struct io_ring_ctx *ctx,
8967 struct task_struct *task, bool cancel_all)
8969 struct io_defer_entry *de;
8972 spin_lock(&ctx->completion_lock);
8973 list_for_each_entry_reverse(de, &ctx->defer_list, list) {
8974 if (io_match_task(de->req, task, cancel_all)) {
8975 list_cut_position(&list, &ctx->defer_list, &de->list);
8979 spin_unlock(&ctx->completion_lock);
8980 if (list_empty(&list))
8983 while (!list_empty(&list)) {
8984 de = list_first_entry(&list, struct io_defer_entry, list);
8985 list_del_init(&de->list);
8986 io_req_complete_failed(de->req, -ECANCELED);
8992 static bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
8994 struct io_tctx_node *node;
8995 enum io_wq_cancel cret;
8998 mutex_lock(&ctx->uring_lock);
8999 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
9000 struct io_uring_task *tctx = node->task->io_uring;
9003 * io_wq will stay alive while we hold uring_lock, because it's
9004 * killed after ctx nodes, which requires to take the lock.
9006 if (!tctx || !tctx->io_wq)
9008 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
9009 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
9011 mutex_unlock(&ctx->uring_lock);
9016 static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
9017 struct task_struct *task,
9020 struct io_task_cancel cancel = { .task = task, .all = cancel_all, };
9021 struct io_uring_task *tctx = task ? task->io_uring : NULL;
9024 enum io_wq_cancel cret;
9028 ret |= io_uring_try_cancel_iowq(ctx);
9029 } else if (tctx && tctx->io_wq) {
9031 * Cancels requests of all rings, not only @ctx, but
9032 * it's fine as the task is in exit/exec.
9034 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
9036 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
9039 /* SQPOLL thread does its own polling */
9040 if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) ||
9041 (ctx->sq_data && ctx->sq_data->thread == current)) {
9042 while (!list_empty_careful(&ctx->iopoll_list)) {
9043 io_iopoll_try_reap_events(ctx);
9048 ret |= io_cancel_defer_files(ctx, task, cancel_all);
9049 ret |= io_poll_remove_all(ctx, task, cancel_all);
9050 ret |= io_kill_timeouts(ctx, task, cancel_all);
9052 ret |= io_run_task_work();
9059 static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
9061 struct io_uring_task *tctx = current->io_uring;
9062 struct io_tctx_node *node;
9065 if (unlikely(!tctx)) {
9066 ret = io_uring_alloc_task_context(current, ctx);
9069 tctx = current->io_uring;
9071 if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
9072 node = kmalloc(sizeof(*node), GFP_KERNEL);
9076 node->task = current;
9078 ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
9085 mutex_lock(&ctx->uring_lock);
9086 list_add(&node->ctx_node, &ctx->tctx_list);
9087 mutex_unlock(&ctx->uring_lock);
9094 * Note that this task has used io_uring. We use it for cancelation purposes.
9096 static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
9098 struct io_uring_task *tctx = current->io_uring;
9100 if (likely(tctx && tctx->last == ctx))
9102 return __io_uring_add_tctx_node(ctx);
9106 * Remove this io_uring_file -> task mapping.
9108 static void io_uring_del_tctx_node(unsigned long index)
9110 struct io_uring_task *tctx = current->io_uring;
9111 struct io_tctx_node *node;
9115 node = xa_erase(&tctx->xa, index);
9119 WARN_ON_ONCE(current != node->task);
9120 WARN_ON_ONCE(list_empty(&node->ctx_node));
9122 mutex_lock(&node->ctx->uring_lock);
9123 list_del(&node->ctx_node);
9124 mutex_unlock(&node->ctx->uring_lock);
9126 if (tctx->last == node->ctx)
9131 static void io_uring_clean_tctx(struct io_uring_task *tctx)
9133 struct io_wq *wq = tctx->io_wq;
9134 struct io_tctx_node *node;
9135 unsigned long index;
9137 xa_for_each(&tctx->xa, index, node)
9138 io_uring_del_tctx_node(index);
9141 * Must be after io_uring_del_task_file() (removes nodes under
9142 * uring_lock) to avoid race with io_uring_try_cancel_iowq().
9145 io_wq_put_and_exit(wq);
9149 static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
9152 return atomic_read(&tctx->inflight_tracked);
9153 return percpu_counter_sum(&tctx->inflight);
9156 static void io_uring_drop_tctx_refs(struct task_struct *task)
9158 struct io_uring_task *tctx = task->io_uring;
9159 unsigned int refs = tctx->cached_refs;
9162 tctx->cached_refs = 0;
9163 percpu_counter_sub(&tctx->inflight, refs);
9164 put_task_struct_many(task, refs);
9169 * Find any io_uring ctx that this task has registered or done IO on, and cancel
9170 * requests. @sqd should be not-null IIF it's an SQPOLL thread cancellation.
9172 static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd)
9174 struct io_uring_task *tctx = current->io_uring;
9175 struct io_ring_ctx *ctx;
9179 WARN_ON_ONCE(sqd && sqd->thread != current);
9181 if (!current->io_uring)
9184 io_wq_exit_start(tctx->io_wq);
9186 atomic_inc(&tctx->in_idle);
9188 io_uring_drop_tctx_refs(current);
9189 /* read completions before cancelations */
9190 inflight = tctx_inflight(tctx, !cancel_all);
9195 struct io_tctx_node *node;
9196 unsigned long index;
9198 xa_for_each(&tctx->xa, index, node) {
9199 /* sqpoll task will cancel all its requests */
9200 if (node->ctx->sq_data)
9202 io_uring_try_cancel_requests(node->ctx, current,
9206 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
9207 io_uring_try_cancel_requests(ctx, current,
9211 prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
9212 io_uring_drop_tctx_refs(current);
9214 * If we've seen completions, retry without waiting. This
9215 * avoids a race where a completion comes in before we did
9216 * prepare_to_wait().
9218 if (inflight == tctx_inflight(tctx, !cancel_all))
9220 finish_wait(&tctx->wait, &wait);
9222 atomic_dec(&tctx->in_idle);
9224 io_uring_clean_tctx(tctx);
9226 /* for exec all current's requests should be gone, kill tctx */
9227 __io_uring_free(current);
9231 void __io_uring_cancel(bool cancel_all)
9233 io_uring_cancel_generic(cancel_all, NULL);
9236 static void *io_uring_validate_mmap_request(struct file *file,
9237 loff_t pgoff, size_t sz)
9239 struct io_ring_ctx *ctx = file->private_data;
9240 loff_t offset = pgoff << PAGE_SHIFT;
9245 case IORING_OFF_SQ_RING:
9246 case IORING_OFF_CQ_RING:
9249 case IORING_OFF_SQES:
9253 return ERR_PTR(-EINVAL);
9256 page = virt_to_head_page(ptr);
9257 if (sz > page_size(page))
9258 return ERR_PTR(-EINVAL);
9265 static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
9267 size_t sz = vma->vm_end - vma->vm_start;
9271 ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
9273 return PTR_ERR(ptr);
9275 pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
9276 return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
9279 #else /* !CONFIG_MMU */
9281 static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
9283 return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
9286 static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
9288 return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
9291 static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
9292 unsigned long addr, unsigned long len,
9293 unsigned long pgoff, unsigned long flags)
9297 ptr = io_uring_validate_mmap_request(file, pgoff, len);
9299 return PTR_ERR(ptr);
9301 return (unsigned long) ptr;
9304 #endif /* !CONFIG_MMU */
9306 static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
9311 if (!io_sqring_full(ctx))
9313 prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
9315 if (!io_sqring_full(ctx))
9318 } while (!signal_pending(current));
9320 finish_wait(&ctx->sqo_sq_wait, &wait);
9324 static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
9325 struct __kernel_timespec __user **ts,
9326 const sigset_t __user **sig)
9328 struct io_uring_getevents_arg arg;
9331 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9332 * is just a pointer to the sigset_t.
9334 if (!(flags & IORING_ENTER_EXT_ARG)) {
9335 *sig = (const sigset_t __user *) argp;
9341 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9342 * timespec and sigset_t pointers if good.
9344 if (*argsz != sizeof(arg))
9346 if (copy_from_user(&arg, argp, sizeof(arg)))
9348 *sig = u64_to_user_ptr(arg.sigmask);
9349 *argsz = arg.sigmask_sz;
9350 *ts = u64_to_user_ptr(arg.ts);
9354 SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
9355 u32, min_complete, u32, flags, const void __user *, argp,
9358 struct io_ring_ctx *ctx;
9365 if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
9366 IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG)))
9370 if (unlikely(!f.file))
9374 if (unlikely(f.file->f_op != &io_uring_fops))
9378 ctx = f.file->private_data;
9379 if (unlikely(!percpu_ref_tryget(&ctx->refs)))
9383 if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED))
9387 * For SQ polling, the thread will do all submissions and completions.
9388 * Just return the requested submit count, and wake the thread if
9392 if (ctx->flags & IORING_SETUP_SQPOLL) {
9393 io_cqring_overflow_flush(ctx);
9395 if (unlikely(ctx->sq_data->thread == NULL)) {
9399 if (flags & IORING_ENTER_SQ_WAKEUP)
9400 wake_up(&ctx->sq_data->wait);
9401 if (flags & IORING_ENTER_SQ_WAIT) {
9402 ret = io_sqpoll_wait_sq(ctx);
9406 submitted = to_submit;
9407 } else if (to_submit) {
9408 ret = io_uring_add_tctx_node(ctx);
9411 mutex_lock(&ctx->uring_lock);
9412 submitted = io_submit_sqes(ctx, to_submit);
9413 mutex_unlock(&ctx->uring_lock);
9415 if (submitted != to_submit)
9418 if (flags & IORING_ENTER_GETEVENTS) {
9419 const sigset_t __user *sig;
9420 struct __kernel_timespec __user *ts;
9422 ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
9426 min_complete = min(min_complete, ctx->cq_entries);
9429 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9430 * space applications don't need to do io completion events
9431 * polling again, they can rely on io_sq_thread to do polling
9432 * work, which can reduce cpu usage and uring_lock contention.
9434 if (ctx->flags & IORING_SETUP_IOPOLL &&
9435 !(ctx->flags & IORING_SETUP_SQPOLL)) {
9436 ret = io_iopoll_check(ctx, min_complete);
9438 ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts);
9443 percpu_ref_put(&ctx->refs);
9446 return submitted ? submitted : ret;
9449 #ifdef CONFIG_PROC_FS
9450 static int io_uring_show_cred(struct seq_file *m, unsigned int id,
9451 const struct cred *cred)
9453 struct user_namespace *uns = seq_user_ns(m);
9454 struct group_info *gi;
9459 seq_printf(m, "%5d\n", id);
9460 seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
9461 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
9462 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
9463 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
9464 seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
9465 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
9466 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
9467 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
9468 seq_puts(m, "\n\tGroups:\t");
9469 gi = cred->group_info;
9470 for (g = 0; g < gi->ngroups; g++) {
9471 seq_put_decimal_ull(m, g ? " " : "",
9472 from_kgid_munged(uns, gi->gid[g]));
9474 seq_puts(m, "\n\tCapEff:\t");
9475 cap = cred->cap_effective;
9476 CAP_FOR_EACH_U32(__capi)
9477 seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
9482 static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
9484 struct io_sq_data *sq = NULL;
9489 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9490 * since fdinfo case grabs it in the opposite direction of normal use
9491 * cases. If we fail to get the lock, we just don't iterate any
9492 * structures that could be going away outside the io_uring mutex.
9494 has_lock = mutex_trylock(&ctx->uring_lock);
9496 if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
9502 seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
9503 seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
9504 seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
9505 for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
9506 struct file *f = io_file_from_index(ctx, i);
9509 seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
9511 seq_printf(m, "%5u: <none>\n", i);
9513 seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
9514 for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
9515 struct io_mapped_ubuf *buf = ctx->user_bufs[i];
9516 unsigned int len = buf->ubuf_end - buf->ubuf;
9518 seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
9520 if (has_lock && !xa_empty(&ctx->personalities)) {
9521 unsigned long index;
9522 const struct cred *cred;
9524 seq_printf(m, "Personalities:\n");
9525 xa_for_each(&ctx->personalities, index, cred)
9526 io_uring_show_cred(m, index, cred);
9528 seq_printf(m, "PollList:\n");
9529 spin_lock(&ctx->completion_lock);
9530 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
9531 struct hlist_head *list = &ctx->cancel_hash[i];
9532 struct io_kiocb *req;
9534 hlist_for_each_entry(req, list, hash_node)
9535 seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
9536 req->task->task_works != NULL);
9538 spin_unlock(&ctx->completion_lock);
9540 mutex_unlock(&ctx->uring_lock);
9543 static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
9545 struct io_ring_ctx *ctx = f->private_data;
9547 if (percpu_ref_tryget(&ctx->refs)) {
9548 __io_uring_show_fdinfo(ctx, m);
9549 percpu_ref_put(&ctx->refs);
9554 static const struct file_operations io_uring_fops = {
9555 .release = io_uring_release,
9556 .mmap = io_uring_mmap,
9558 .get_unmapped_area = io_uring_nommu_get_unmapped_area,
9559 .mmap_capabilities = io_uring_nommu_mmap_capabilities,
9561 .poll = io_uring_poll,
9562 .fasync = io_uring_fasync,
9563 #ifdef CONFIG_PROC_FS
9564 .show_fdinfo = io_uring_show_fdinfo,
9568 static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
9569 struct io_uring_params *p)
9571 struct io_rings *rings;
9572 size_t size, sq_array_offset;
9574 /* make sure these are sane, as we already accounted them */
9575 ctx->sq_entries = p->sq_entries;
9576 ctx->cq_entries = p->cq_entries;
9578 size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
9579 if (size == SIZE_MAX)
9582 rings = io_mem_alloc(size);
9587 ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
9588 rings->sq_ring_mask = p->sq_entries - 1;
9589 rings->cq_ring_mask = p->cq_entries - 1;
9590 rings->sq_ring_entries = p->sq_entries;
9591 rings->cq_ring_entries = p->cq_entries;
9593 size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
9594 if (size == SIZE_MAX) {
9595 io_mem_free(ctx->rings);
9600 ctx->sq_sqes = io_mem_alloc(size);
9601 if (!ctx->sq_sqes) {
9602 io_mem_free(ctx->rings);
9610 static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
9614 fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
9618 ret = io_uring_add_tctx_node(ctx);
9623 fd_install(fd, file);
9628 * Allocate an anonymous fd, this is what constitutes the application
9629 * visible backing of an io_uring instance. The application mmaps this
9630 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
9631 * we have to tie this fd to a socket for file garbage collection purposes.
9633 static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
9636 #if defined(CONFIG_UNIX)
9639 ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
9642 return ERR_PTR(ret);
9645 file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
9646 O_RDWR | O_CLOEXEC);
9647 #if defined(CONFIG_UNIX)
9649 sock_release(ctx->ring_sock);
9650 ctx->ring_sock = NULL;
9652 ctx->ring_sock->file = file;
9658 static int io_uring_create(unsigned entries, struct io_uring_params *p,
9659 struct io_uring_params __user *params)
9661 struct io_ring_ctx *ctx;
9667 if (entries > IORING_MAX_ENTRIES) {
9668 if (!(p->flags & IORING_SETUP_CLAMP))
9670 entries = IORING_MAX_ENTRIES;
9674 * Use twice as many entries for the CQ ring. It's possible for the
9675 * application to drive a higher depth than the size of the SQ ring,
9676 * since the sqes are only used at submission time. This allows for
9677 * some flexibility in overcommitting a bit. If the application has
9678 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
9679 * of CQ ring entries manually.
9681 p->sq_entries = roundup_pow_of_two(entries);
9682 if (p->flags & IORING_SETUP_CQSIZE) {
9684 * If IORING_SETUP_CQSIZE is set, we do the same roundup
9685 * to a power-of-two, if it isn't already. We do NOT impose
9686 * any cq vs sq ring sizing.
9690 if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
9691 if (!(p->flags & IORING_SETUP_CLAMP))
9693 p->cq_entries = IORING_MAX_CQ_ENTRIES;
9695 p->cq_entries = roundup_pow_of_two(p->cq_entries);
9696 if (p->cq_entries < p->sq_entries)
9699 p->cq_entries = 2 * p->sq_entries;
9702 ctx = io_ring_ctx_alloc(p);
9705 ctx->compat = in_compat_syscall();
9706 if (!capable(CAP_IPC_LOCK))
9707 ctx->user = get_uid(current_user());
9710 * This is just grabbed for accounting purposes. When a process exits,
9711 * the mm is exited and dropped before the files, hence we need to hang
9712 * on to this mm purely for the purposes of being able to unaccount
9713 * memory (locked/pinned vm). It's not used for anything else.
9715 mmgrab(current->mm);
9716 ctx->mm_account = current->mm;
9718 ret = io_allocate_scq_urings(ctx, p);
9722 ret = io_sq_offload_create(ctx, p);
9725 /* always set a rsrc node */
9726 ret = io_rsrc_node_switch_start(ctx);
9729 io_rsrc_node_switch(ctx, NULL);
9731 memset(&p->sq_off, 0, sizeof(p->sq_off));
9732 p->sq_off.head = offsetof(struct io_rings, sq.head);
9733 p->sq_off.tail = offsetof(struct io_rings, sq.tail);
9734 p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
9735 p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
9736 p->sq_off.flags = offsetof(struct io_rings, sq_flags);
9737 p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
9738 p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
9740 memset(&p->cq_off, 0, sizeof(p->cq_off));
9741 p->cq_off.head = offsetof(struct io_rings, cq.head);
9742 p->cq_off.tail = offsetof(struct io_rings, cq.tail);
9743 p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
9744 p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
9745 p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
9746 p->cq_off.cqes = offsetof(struct io_rings, cqes);
9747 p->cq_off.flags = offsetof(struct io_rings, cq_flags);
9749 p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
9750 IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
9751 IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
9752 IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
9753 IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS |
9754 IORING_FEAT_RSRC_TAGS;
9756 if (copy_to_user(params, p, sizeof(*p))) {
9761 file = io_uring_get_file(ctx);
9763 ret = PTR_ERR(file);
9768 * Install ring fd as the very last thing, so we don't risk someone
9769 * having closed it before we finish setup
9771 ret = io_uring_install_fd(ctx, file);
9773 /* fput will clean it up */
9778 trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
9781 io_ring_ctx_wait_and_kill(ctx);
9786 * Sets up an aio uring context, and returns the fd. Applications asks for a
9787 * ring size, we return the actual sq/cq ring sizes (among other things) in the
9788 * params structure passed in.
9790 static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
9792 struct io_uring_params p;
9795 if (copy_from_user(&p, params, sizeof(p)))
9797 for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
9802 if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
9803 IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
9804 IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
9805 IORING_SETUP_R_DISABLED))
9808 return io_uring_create(entries, &p, params);
9811 SYSCALL_DEFINE2(io_uring_setup, u32, entries,
9812 struct io_uring_params __user *, params)
9814 return io_uring_setup(entries, params);
9817 static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
9819 struct io_uring_probe *p;
9823 size = struct_size(p, ops, nr_args);
9824 if (size == SIZE_MAX)
9826 p = kzalloc(size, GFP_KERNEL);
9831 if (copy_from_user(p, arg, size))
9834 if (memchr_inv(p, 0, size))
9837 p->last_op = IORING_OP_LAST - 1;
9838 if (nr_args > IORING_OP_LAST)
9839 nr_args = IORING_OP_LAST;
9841 for (i = 0; i < nr_args; i++) {
9843 if (!io_op_defs[i].not_supported)
9844 p->ops[i].flags = IO_URING_OP_SUPPORTED;
9849 if (copy_to_user(arg, p, size))
9856 static int io_register_personality(struct io_ring_ctx *ctx)
9858 const struct cred *creds;
9862 creds = get_current_cred();
9864 ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
9865 XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
9873 static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
9874 unsigned int nr_args)
9876 struct io_uring_restriction *res;
9880 /* Restrictions allowed only if rings started disabled */
9881 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
9884 /* We allow only a single restrictions registration */
9885 if (ctx->restrictions.registered)
9888 if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
9891 size = array_size(nr_args, sizeof(*res));
9892 if (size == SIZE_MAX)
9895 res = memdup_user(arg, size);
9897 return PTR_ERR(res);
9901 for (i = 0; i < nr_args; i++) {
9902 switch (res[i].opcode) {
9903 case IORING_RESTRICTION_REGISTER_OP:
9904 if (res[i].register_op >= IORING_REGISTER_LAST) {
9909 __set_bit(res[i].register_op,
9910 ctx->restrictions.register_op);
9912 case IORING_RESTRICTION_SQE_OP:
9913 if (res[i].sqe_op >= IORING_OP_LAST) {
9918 __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
9920 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
9921 ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
9923 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
9924 ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
9933 /* Reset all restrictions if an error happened */
9935 memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
9937 ctx->restrictions.registered = true;
9943 static int io_register_enable_rings(struct io_ring_ctx *ctx)
9945 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
9948 if (ctx->restrictions.registered)
9949 ctx->restricted = 1;
9951 ctx->flags &= ~IORING_SETUP_R_DISABLED;
9952 if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
9953 wake_up(&ctx->sq_data->wait);
9957 static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
9958 struct io_uring_rsrc_update2 *up,
9966 if (check_add_overflow(up->offset, nr_args, &tmp))
9968 err = io_rsrc_node_switch_start(ctx);
9973 case IORING_RSRC_FILE:
9974 return __io_sqe_files_update(ctx, up, nr_args);
9975 case IORING_RSRC_BUFFER:
9976 return __io_sqe_buffers_update(ctx, up, nr_args);
9981 static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
9984 struct io_uring_rsrc_update2 up;
9988 memset(&up, 0, sizeof(up));
9989 if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update)))
9991 return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args);
9994 static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
9995 unsigned size, unsigned type)
9997 struct io_uring_rsrc_update2 up;
9999 if (size != sizeof(up))
10001 if (copy_from_user(&up, arg, sizeof(up)))
10003 if (!up.nr || up.resv)
10005 return __io_register_rsrc_update(ctx, type, &up, up.nr);
10008 static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
10009 unsigned int size, unsigned int type)
10011 struct io_uring_rsrc_register rr;
10013 /* keep it extendible */
10014 if (size != sizeof(rr))
10017 memset(&rr, 0, sizeof(rr));
10018 if (copy_from_user(&rr, arg, size))
10020 if (!rr.nr || rr.resv || rr.resv2)
10024 case IORING_RSRC_FILE:
10025 return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data),
10026 rr.nr, u64_to_user_ptr(rr.tags));
10027 case IORING_RSRC_BUFFER:
10028 return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data),
10029 rr.nr, u64_to_user_ptr(rr.tags));
10034 static int io_register_iowq_aff(struct io_ring_ctx *ctx, void __user *arg,
10037 struct io_uring_task *tctx = current->io_uring;
10038 cpumask_var_t new_mask;
10041 if (!tctx || !tctx->io_wq)
10044 if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
10047 cpumask_clear(new_mask);
10048 if (len > cpumask_size())
10049 len = cpumask_size();
10051 if (copy_from_user(new_mask, arg, len)) {
10052 free_cpumask_var(new_mask);
10056 ret = io_wq_cpu_affinity(tctx->io_wq, new_mask);
10057 free_cpumask_var(new_mask);
10061 static int io_unregister_iowq_aff(struct io_ring_ctx *ctx)
10063 struct io_uring_task *tctx = current->io_uring;
10065 if (!tctx || !tctx->io_wq)
10068 return io_wq_cpu_affinity(tctx->io_wq, NULL);
10071 static bool io_register_op_must_quiesce(int op)
10074 case IORING_REGISTER_BUFFERS:
10075 case IORING_UNREGISTER_BUFFERS:
10076 case IORING_REGISTER_FILES:
10077 case IORING_UNREGISTER_FILES:
10078 case IORING_REGISTER_FILES_UPDATE:
10079 case IORING_REGISTER_PROBE:
10080 case IORING_REGISTER_PERSONALITY:
10081 case IORING_UNREGISTER_PERSONALITY:
10082 case IORING_REGISTER_FILES2:
10083 case IORING_REGISTER_FILES_UPDATE2:
10084 case IORING_REGISTER_BUFFERS2:
10085 case IORING_REGISTER_BUFFERS_UPDATE:
10086 case IORING_REGISTER_IOWQ_AFF:
10087 case IORING_UNREGISTER_IOWQ_AFF:
10094 static int io_ctx_quiesce(struct io_ring_ctx *ctx)
10098 percpu_ref_kill(&ctx->refs);
10101 * Drop uring mutex before waiting for references to exit. If another
10102 * thread is currently inside io_uring_enter() it might need to grab the
10103 * uring_lock to make progress. If we hold it here across the drain
10104 * wait, then we can deadlock. It's safe to drop the mutex here, since
10105 * no new references will come in after we've killed the percpu ref.
10107 mutex_unlock(&ctx->uring_lock);
10109 ret = wait_for_completion_interruptible(&ctx->ref_comp);
10112 ret = io_run_task_work_sig();
10113 } while (ret >= 0);
10114 mutex_lock(&ctx->uring_lock);
10117 io_refs_resurrect(&ctx->refs, &ctx->ref_comp);
10121 static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
10122 void __user *arg, unsigned nr_args)
10123 __releases(ctx->uring_lock)
10124 __acquires(ctx->uring_lock)
10129 * We're inside the ring mutex, if the ref is already dying, then
10130 * someone else killed the ctx or is already going through
10131 * io_uring_register().
10133 if (percpu_ref_is_dying(&ctx->refs))
10136 if (ctx->restricted) {
10137 if (opcode >= IORING_REGISTER_LAST)
10139 opcode = array_index_nospec(opcode, IORING_REGISTER_LAST);
10140 if (!test_bit(opcode, ctx->restrictions.register_op))
10144 if (io_register_op_must_quiesce(opcode)) {
10145 ret = io_ctx_quiesce(ctx);
10151 case IORING_REGISTER_BUFFERS:
10152 ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL);
10154 case IORING_UNREGISTER_BUFFERS:
10156 if (arg || nr_args)
10158 ret = io_sqe_buffers_unregister(ctx);
10160 case IORING_REGISTER_FILES:
10161 ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
10163 case IORING_UNREGISTER_FILES:
10165 if (arg || nr_args)
10167 ret = io_sqe_files_unregister(ctx);
10169 case IORING_REGISTER_FILES_UPDATE:
10170 ret = io_register_files_update(ctx, arg, nr_args);
10172 case IORING_REGISTER_EVENTFD:
10173 case IORING_REGISTER_EVENTFD_ASYNC:
10177 ret = io_eventfd_register(ctx, arg);
10180 if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
10181 ctx->eventfd_async = 1;
10183 ctx->eventfd_async = 0;
10185 case IORING_UNREGISTER_EVENTFD:
10187 if (arg || nr_args)
10189 ret = io_eventfd_unregister(ctx);
10191 case IORING_REGISTER_PROBE:
10193 if (!arg || nr_args > 256)
10195 ret = io_probe(ctx, arg, nr_args);
10197 case IORING_REGISTER_PERSONALITY:
10199 if (arg || nr_args)
10201 ret = io_register_personality(ctx);
10203 case IORING_UNREGISTER_PERSONALITY:
10207 ret = io_unregister_personality(ctx, nr_args);
10209 case IORING_REGISTER_ENABLE_RINGS:
10211 if (arg || nr_args)
10213 ret = io_register_enable_rings(ctx);
10215 case IORING_REGISTER_RESTRICTIONS:
10216 ret = io_register_restrictions(ctx, arg, nr_args);
10218 case IORING_REGISTER_FILES2:
10219 ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE);
10221 case IORING_REGISTER_FILES_UPDATE2:
10222 ret = io_register_rsrc_update(ctx, arg, nr_args,
10225 case IORING_REGISTER_BUFFERS2:
10226 ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER);
10228 case IORING_REGISTER_BUFFERS_UPDATE:
10229 ret = io_register_rsrc_update(ctx, arg, nr_args,
10230 IORING_RSRC_BUFFER);
10232 case IORING_REGISTER_IOWQ_AFF:
10234 if (!arg || !nr_args)
10236 ret = io_register_iowq_aff(ctx, arg, nr_args);
10238 case IORING_UNREGISTER_IOWQ_AFF:
10240 if (arg || nr_args)
10242 ret = io_unregister_iowq_aff(ctx);
10249 if (io_register_op_must_quiesce(opcode)) {
10250 /* bring the ctx back to life */
10251 percpu_ref_reinit(&ctx->refs);
10252 reinit_completion(&ctx->ref_comp);
10257 SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
10258 void __user *, arg, unsigned int, nr_args)
10260 struct io_ring_ctx *ctx;
10269 if (f.file->f_op != &io_uring_fops)
10272 ctx = f.file->private_data;
10274 io_run_task_work();
10276 mutex_lock(&ctx->uring_lock);
10277 ret = __io_uring_register(ctx, opcode, arg, nr_args);
10278 mutex_unlock(&ctx->uring_lock);
10279 trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
10280 ctx->cq_ev_fd != NULL, ret);
10286 static int __init io_uring_init(void)
10288 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10289 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10290 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10293 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10294 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10295 BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
10296 BUILD_BUG_SQE_ELEM(0, __u8, opcode);
10297 BUILD_BUG_SQE_ELEM(1, __u8, flags);
10298 BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
10299 BUILD_BUG_SQE_ELEM(4, __s32, fd);
10300 BUILD_BUG_SQE_ELEM(8, __u64, off);
10301 BUILD_BUG_SQE_ELEM(8, __u64, addr2);
10302 BUILD_BUG_SQE_ELEM(16, __u64, addr);
10303 BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
10304 BUILD_BUG_SQE_ELEM(24, __u32, len);
10305 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
10306 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
10307 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
10308 BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
10309 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
10310 BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
10311 BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
10312 BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
10313 BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
10314 BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
10315 BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
10316 BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
10317 BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
10318 BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
10319 BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
10320 BUILD_BUG_SQE_ELEM(32, __u64, user_data);
10321 BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
10322 BUILD_BUG_SQE_ELEM(40, __u16, buf_group);
10323 BUILD_BUG_SQE_ELEM(42, __u16, personality);
10324 BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
10326 BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=
10327 sizeof(struct io_uring_rsrc_update));
10328 BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) >
10329 sizeof(struct io_uring_rsrc_update2));
10330 /* should fit into one byte */
10331 BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));
10333 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
10334 BUILD_BUG_ON(__REQ_F_LAST_BIT >= 8 * sizeof(int));
10336 req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
10340 __initcall(io_uring_init);