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
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 (PAGE_SHIFT - 3)
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 ltimeout_list;
379 struct list_head cq_overflow_list;
380 struct xarray io_buffers;
381 struct xarray personalities;
383 unsigned sq_thread_idle;
384 } ____cacheline_aligned_in_smp;
386 /* IRQ completion list, under ->completion_lock */
387 struct list_head locked_free_list;
388 unsigned int locked_free_nr;
390 const struct cred *sq_creds; /* cred used for __io_sq_thread() */
391 struct io_sq_data *sq_data; /* if using sq thread polling */
393 struct wait_queue_head sqo_sq_wait;
394 struct list_head sqd_list;
396 unsigned long check_cq_overflow;
399 unsigned cached_cq_tail;
401 struct eventfd_ctx *cq_ev_fd;
402 struct wait_queue_head poll_wait;
403 struct wait_queue_head cq_wait;
405 atomic_t cq_timeouts;
406 struct fasync_struct *cq_fasync;
407 unsigned cq_last_tm_flush;
408 } ____cacheline_aligned_in_smp;
411 spinlock_t completion_lock;
413 spinlock_t timeout_lock;
416 * ->iopoll_list is protected by the ctx->uring_lock for
417 * io_uring instances that don't use IORING_SETUP_SQPOLL.
418 * For SQPOLL, only the single threaded io_sq_thread() will
419 * manipulate the list, hence no extra locking is needed there.
421 struct list_head iopoll_list;
422 struct hlist_head *cancel_hash;
423 unsigned cancel_hash_bits;
424 bool poll_multi_queue;
425 } ____cacheline_aligned_in_smp;
427 struct io_restriction restrictions;
429 /* slow path rsrc auxilary data, used by update/register */
431 struct io_rsrc_node *rsrc_backup_node;
432 struct io_mapped_ubuf *dummy_ubuf;
433 struct io_rsrc_data *file_data;
434 struct io_rsrc_data *buf_data;
436 struct delayed_work rsrc_put_work;
437 struct llist_head rsrc_put_llist;
438 struct list_head rsrc_ref_list;
439 spinlock_t rsrc_ref_lock;
442 /* Keep this last, we don't need it for the fast path */
444 #if defined(CONFIG_UNIX)
445 struct socket *ring_sock;
447 /* hashed buffered write serialization */
448 struct io_wq_hash *hash_map;
450 /* Only used for accounting purposes */
451 struct user_struct *user;
452 struct mm_struct *mm_account;
454 /* ctx exit and cancelation */
455 struct llist_head fallback_llist;
456 struct delayed_work fallback_work;
457 struct work_struct exit_work;
458 struct list_head tctx_list;
459 struct completion ref_comp;
463 struct io_uring_task {
464 /* submission side */
467 struct wait_queue_head wait;
468 const struct io_ring_ctx *last;
470 struct percpu_counter inflight;
471 atomic_t inflight_tracked;
474 spinlock_t task_lock;
475 struct io_wq_work_list task_list;
476 struct callback_head task_work;
481 * First field must be the file pointer in all the
482 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
484 struct io_poll_iocb {
486 struct wait_queue_head *head;
490 struct wait_queue_entry wait;
493 struct io_poll_update {
499 bool update_user_data;
507 struct io_timeout_data {
508 struct io_kiocb *req;
509 struct hrtimer timer;
510 struct timespec64 ts;
511 enum hrtimer_mode mode;
517 struct sockaddr __user *addr;
518 int __user *addr_len;
521 unsigned long nofile;
541 struct list_head list;
542 /* head of the link, used by linked timeouts only */
543 struct io_kiocb *head;
544 /* for linked completions */
545 struct io_kiocb *prev;
548 struct io_timeout_rem {
553 struct timespec64 ts;
559 /* NOTE: kiocb has the file as the first member, so don't do it here */
567 struct sockaddr __user *addr;
574 struct compat_msghdr __user *umsg_compat;
575 struct user_msghdr __user *umsg;
581 struct io_buffer *kbuf;
588 struct filename *filename;
590 unsigned long nofile;
593 struct io_rsrc_update {
619 struct epoll_event event;
623 struct file *file_out;
624 struct file *file_in;
631 struct io_provide_buf {
645 const char __user *filename;
646 struct statx __user *buffer;
658 struct filename *oldpath;
659 struct filename *newpath;
667 struct filename *filename;
674 struct filename *filename;
680 struct filename *oldpath;
681 struct filename *newpath;
688 struct filename *oldpath;
689 struct filename *newpath;
693 struct io_completion {
698 struct io_async_connect {
699 struct sockaddr_storage address;
702 struct io_async_msghdr {
703 struct iovec fast_iov[UIO_FASTIOV];
704 /* points to an allocated iov, if NULL we use fast_iov instead */
705 struct iovec *free_iov;
706 struct sockaddr __user *uaddr;
708 struct sockaddr_storage addr;
712 struct iovec fast_iov[UIO_FASTIOV];
713 const struct iovec *free_iovec;
714 struct iov_iter iter;
716 struct wait_page_queue wpq;
720 REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
721 REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
722 REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
723 REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
724 REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
725 REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
727 /* first byte is taken by user flags, shift it to not overlap */
732 REQ_F_LINK_TIMEOUT_BIT,
733 REQ_F_NEED_CLEANUP_BIT,
735 REQ_F_BUFFER_SELECTED_BIT,
736 REQ_F_COMPLETE_INLINE_BIT,
738 REQ_F_DONT_REISSUE_BIT,
741 REQ_F_ARM_LTIMEOUT_BIT,
742 /* keep async read/write and isreg together and in order */
743 REQ_F_NOWAIT_READ_BIT,
744 REQ_F_NOWAIT_WRITE_BIT,
747 /* not a real bit, just to check we're not overflowing the space */
753 REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
754 /* drain existing IO first */
755 REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
757 REQ_F_LINK = BIT(REQ_F_LINK_BIT),
758 /* doesn't sever on completion < 0 */
759 REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
761 REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
762 /* IOSQE_BUFFER_SELECT */
763 REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
765 /* fail rest of links */
766 REQ_F_FAIL = BIT(REQ_F_FAIL_BIT),
767 /* on inflight list, should be cancelled and waited on exit reliably */
768 REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
769 /* read/write uses file position */
770 REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
771 /* must not punt to workers */
772 REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
773 /* has or had linked timeout */
774 REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
776 REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
777 /* already went through poll handler */
778 REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
779 /* buffer already selected */
780 REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
781 /* completion is deferred through io_comp_state */
782 REQ_F_COMPLETE_INLINE = BIT(REQ_F_COMPLETE_INLINE_BIT),
783 /* caller should reissue async */
784 REQ_F_REISSUE = BIT(REQ_F_REISSUE_BIT),
785 /* don't attempt request reissue, see io_rw_reissue() */
786 REQ_F_DONT_REISSUE = BIT(REQ_F_DONT_REISSUE_BIT),
787 /* supports async reads */
788 REQ_F_NOWAIT_READ = BIT(REQ_F_NOWAIT_READ_BIT),
789 /* supports async writes */
790 REQ_F_NOWAIT_WRITE = BIT(REQ_F_NOWAIT_WRITE_BIT),
792 REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
793 /* has creds assigned */
794 REQ_F_CREDS = BIT(REQ_F_CREDS_BIT),
795 /* skip refcounting if not set */
796 REQ_F_REFCOUNT = BIT(REQ_F_REFCOUNT_BIT),
797 /* there is a linked timeout that has to be armed */
798 REQ_F_ARM_LTIMEOUT = BIT(REQ_F_ARM_LTIMEOUT_BIT),
802 struct io_poll_iocb poll;
803 struct io_poll_iocb *double_poll;
806 typedef void (*io_req_tw_func_t)(struct io_kiocb *req, bool *locked);
808 struct io_task_work {
810 struct io_wq_work_node node;
811 struct llist_node fallback_node;
813 io_req_tw_func_t func;
817 IORING_RSRC_FILE = 0,
818 IORING_RSRC_BUFFER = 1,
822 * NOTE! Each of the iocb union members has the file pointer
823 * as the first entry in their struct definition. So you can
824 * access the file pointer through any of the sub-structs,
825 * or directly as just 'ki_filp' in this struct.
831 struct io_poll_iocb poll;
832 struct io_poll_update poll_update;
833 struct io_accept accept;
835 struct io_cancel cancel;
836 struct io_timeout timeout;
837 struct io_timeout_rem timeout_rem;
838 struct io_connect connect;
839 struct io_sr_msg sr_msg;
841 struct io_close close;
842 struct io_rsrc_update rsrc_update;
843 struct io_fadvise fadvise;
844 struct io_madvise madvise;
845 struct io_epoll epoll;
846 struct io_splice splice;
847 struct io_provide_buf pbuf;
848 struct io_statx statx;
849 struct io_shutdown shutdown;
850 struct io_rename rename;
851 struct io_unlink unlink;
852 struct io_mkdir mkdir;
853 struct io_symlink symlink;
854 struct io_hardlink hardlink;
855 /* use only after cleaning per-op data, see io_clean_op() */
856 struct io_completion compl;
859 /* opcode allocated if it needs to store data for async defer */
862 /* polled IO has completed */
868 struct io_ring_ctx *ctx;
871 struct task_struct *task;
874 struct io_kiocb *link;
875 struct percpu_ref *fixed_rsrc_refs;
877 /* used with ctx->iopoll_list with reads/writes */
878 struct list_head inflight_entry;
879 struct io_task_work io_task_work;
880 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
881 struct hlist_node hash_node;
882 struct async_poll *apoll;
883 struct io_wq_work work;
884 const struct cred *creds;
886 /* store used ubuf, so we can prevent reloading */
887 struct io_mapped_ubuf *imu;
890 struct io_tctx_node {
891 struct list_head ctx_node;
892 struct task_struct *task;
893 struct io_ring_ctx *ctx;
896 struct io_defer_entry {
897 struct list_head list;
898 struct io_kiocb *req;
903 /* needs req->file assigned */
904 unsigned needs_file : 1;
905 /* hash wq insertion if file is a regular file */
906 unsigned hash_reg_file : 1;
907 /* unbound wq insertion if file is a non-regular file */
908 unsigned unbound_nonreg_file : 1;
909 /* opcode is not supported by this kernel */
910 unsigned not_supported : 1;
911 /* set if opcode supports polled "wait" */
913 unsigned pollout : 1;
914 /* op supports buffer selection */
915 unsigned buffer_select : 1;
916 /* do prep async if is going to be punted */
917 unsigned needs_async_setup : 1;
918 /* should block plug */
920 /* size of async data needed, if any */
921 unsigned short async_size;
924 static const struct io_op_def io_op_defs[] = {
925 [IORING_OP_NOP] = {},
926 [IORING_OP_READV] = {
928 .unbound_nonreg_file = 1,
931 .needs_async_setup = 1,
933 .async_size = sizeof(struct io_async_rw),
935 [IORING_OP_WRITEV] = {
938 .unbound_nonreg_file = 1,
940 .needs_async_setup = 1,
942 .async_size = sizeof(struct io_async_rw),
944 [IORING_OP_FSYNC] = {
947 [IORING_OP_READ_FIXED] = {
949 .unbound_nonreg_file = 1,
952 .async_size = sizeof(struct io_async_rw),
954 [IORING_OP_WRITE_FIXED] = {
957 .unbound_nonreg_file = 1,
960 .async_size = sizeof(struct io_async_rw),
962 [IORING_OP_POLL_ADD] = {
964 .unbound_nonreg_file = 1,
966 [IORING_OP_POLL_REMOVE] = {},
967 [IORING_OP_SYNC_FILE_RANGE] = {
970 [IORING_OP_SENDMSG] = {
972 .unbound_nonreg_file = 1,
974 .needs_async_setup = 1,
975 .async_size = sizeof(struct io_async_msghdr),
977 [IORING_OP_RECVMSG] = {
979 .unbound_nonreg_file = 1,
982 .needs_async_setup = 1,
983 .async_size = sizeof(struct io_async_msghdr),
985 [IORING_OP_TIMEOUT] = {
986 .async_size = sizeof(struct io_timeout_data),
988 [IORING_OP_TIMEOUT_REMOVE] = {
989 /* used by timeout updates' prep() */
991 [IORING_OP_ACCEPT] = {
993 .unbound_nonreg_file = 1,
996 [IORING_OP_ASYNC_CANCEL] = {},
997 [IORING_OP_LINK_TIMEOUT] = {
998 .async_size = sizeof(struct io_timeout_data),
1000 [IORING_OP_CONNECT] = {
1002 .unbound_nonreg_file = 1,
1004 .needs_async_setup = 1,
1005 .async_size = sizeof(struct io_async_connect),
1007 [IORING_OP_FALLOCATE] = {
1010 [IORING_OP_OPENAT] = {},
1011 [IORING_OP_CLOSE] = {},
1012 [IORING_OP_FILES_UPDATE] = {},
1013 [IORING_OP_STATX] = {},
1014 [IORING_OP_READ] = {
1016 .unbound_nonreg_file = 1,
1020 .async_size = sizeof(struct io_async_rw),
1022 [IORING_OP_WRITE] = {
1025 .unbound_nonreg_file = 1,
1028 .async_size = sizeof(struct io_async_rw),
1030 [IORING_OP_FADVISE] = {
1033 [IORING_OP_MADVISE] = {},
1034 [IORING_OP_SEND] = {
1036 .unbound_nonreg_file = 1,
1039 [IORING_OP_RECV] = {
1041 .unbound_nonreg_file = 1,
1045 [IORING_OP_OPENAT2] = {
1047 [IORING_OP_EPOLL_CTL] = {
1048 .unbound_nonreg_file = 1,
1050 [IORING_OP_SPLICE] = {
1053 .unbound_nonreg_file = 1,
1055 [IORING_OP_PROVIDE_BUFFERS] = {},
1056 [IORING_OP_REMOVE_BUFFERS] = {},
1060 .unbound_nonreg_file = 1,
1062 [IORING_OP_SHUTDOWN] = {
1065 [IORING_OP_RENAMEAT] = {},
1066 [IORING_OP_UNLINKAT] = {},
1067 [IORING_OP_MKDIRAT] = {},
1068 [IORING_OP_SYMLINKAT] = {},
1069 [IORING_OP_LINKAT] = {},
1072 /* requests with any of those set should undergo io_disarm_next() */
1073 #define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
1075 static bool io_disarm_next(struct io_kiocb *req);
1076 static void io_uring_del_tctx_node(unsigned long index);
1077 static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
1078 struct task_struct *task,
1080 static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
1082 static bool io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
1083 long res, unsigned int cflags);
1084 static void io_put_req(struct io_kiocb *req);
1085 static void io_put_req_deferred(struct io_kiocb *req);
1086 static void io_dismantle_req(struct io_kiocb *req);
1087 static void io_queue_linked_timeout(struct io_kiocb *req);
1088 static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
1089 struct io_uring_rsrc_update2 *up,
1091 static void io_clean_op(struct io_kiocb *req);
1092 static struct file *io_file_get(struct io_ring_ctx *ctx,
1093 struct io_kiocb *req, int fd, bool fixed);
1094 static void __io_queue_sqe(struct io_kiocb *req);
1095 static void io_rsrc_put_work(struct work_struct *work);
1097 static void io_req_task_queue(struct io_kiocb *req);
1098 static void io_submit_flush_completions(struct io_ring_ctx *ctx);
1099 static int io_req_prep_async(struct io_kiocb *req);
1101 static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
1102 unsigned int issue_flags, u32 slot_index);
1103 static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer);
1105 static struct kmem_cache *req_cachep;
1107 static const struct file_operations io_uring_fops;
1109 struct sock *io_uring_get_socket(struct file *file)
1111 #if defined(CONFIG_UNIX)
1112 if (file->f_op == &io_uring_fops) {
1113 struct io_ring_ctx *ctx = file->private_data;
1115 return ctx->ring_sock->sk;
1120 EXPORT_SYMBOL(io_uring_get_socket);
1122 static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked)
1125 mutex_lock(&ctx->uring_lock);
1130 #define io_for_each_link(pos, head) \
1131 for (pos = (head); pos; pos = pos->link)
1134 * Shamelessly stolen from the mm implementation of page reference checking,
1135 * see commit f958d7b528b1 for details.
1137 #define req_ref_zero_or_close_to_overflow(req) \
1138 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1140 static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
1142 WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
1143 return atomic_inc_not_zero(&req->refs);
1146 static inline bool req_ref_put_and_test(struct io_kiocb *req)
1148 if (likely(!(req->flags & REQ_F_REFCOUNT)))
1151 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1152 return atomic_dec_and_test(&req->refs);
1155 static inline void req_ref_put(struct io_kiocb *req)
1157 WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
1158 WARN_ON_ONCE(req_ref_put_and_test(req));
1161 static inline void req_ref_get(struct io_kiocb *req)
1163 WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
1164 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1165 atomic_inc(&req->refs);
1168 static inline void __io_req_set_refcount(struct io_kiocb *req, int nr)
1170 if (!(req->flags & REQ_F_REFCOUNT)) {
1171 req->flags |= REQ_F_REFCOUNT;
1172 atomic_set(&req->refs, nr);
1176 static inline void io_req_set_refcount(struct io_kiocb *req)
1178 __io_req_set_refcount(req, 1);
1181 static inline void io_req_set_rsrc_node(struct io_kiocb *req)
1183 struct io_ring_ctx *ctx = req->ctx;
1185 if (!req->fixed_rsrc_refs) {
1186 req->fixed_rsrc_refs = &ctx->rsrc_node->refs;
1187 percpu_ref_get(req->fixed_rsrc_refs);
1191 static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl)
1193 bool got = percpu_ref_tryget(ref);
1195 /* already at zero, wait for ->release() */
1197 wait_for_completion(compl);
1198 percpu_ref_resurrect(ref);
1200 percpu_ref_put(ref);
1203 static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
1206 struct io_kiocb *req;
1208 if (task && head->task != task)
1213 io_for_each_link(req, head) {
1214 if (req->flags & REQ_F_INFLIGHT)
1220 static inline void req_set_fail(struct io_kiocb *req)
1222 req->flags |= REQ_F_FAIL;
1225 static inline void req_fail_link_node(struct io_kiocb *req, int res)
1231 static void io_ring_ctx_ref_free(struct percpu_ref *ref)
1233 struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
1235 complete(&ctx->ref_comp);
1238 static inline bool io_is_timeout_noseq(struct io_kiocb *req)
1240 return !req->timeout.off;
1243 static void io_fallback_req_func(struct work_struct *work)
1245 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
1246 fallback_work.work);
1247 struct llist_node *node = llist_del_all(&ctx->fallback_llist);
1248 struct io_kiocb *req, *tmp;
1249 bool locked = false;
1251 percpu_ref_get(&ctx->refs);
1252 llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node)
1253 req->io_task_work.func(req, &locked);
1256 if (ctx->submit_state.compl_nr)
1257 io_submit_flush_completions(ctx);
1258 mutex_unlock(&ctx->uring_lock);
1260 percpu_ref_put(&ctx->refs);
1264 static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
1266 struct io_ring_ctx *ctx;
1269 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1274 * Use 5 bits less than the max cq entries, that should give us around
1275 * 32 entries per hash list if totally full and uniformly spread.
1277 hash_bits = ilog2(p->cq_entries);
1281 ctx->cancel_hash_bits = hash_bits;
1282 ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
1284 if (!ctx->cancel_hash)
1286 __hash_init(ctx->cancel_hash, 1U << hash_bits);
1288 ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL);
1289 if (!ctx->dummy_ubuf)
1291 /* set invalid range, so io_import_fixed() fails meeting it */
1292 ctx->dummy_ubuf->ubuf = -1UL;
1294 if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
1295 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
1298 ctx->flags = p->flags;
1299 init_waitqueue_head(&ctx->sqo_sq_wait);
1300 INIT_LIST_HEAD(&ctx->sqd_list);
1301 init_waitqueue_head(&ctx->poll_wait);
1302 INIT_LIST_HEAD(&ctx->cq_overflow_list);
1303 init_completion(&ctx->ref_comp);
1304 xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
1305 xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
1306 mutex_init(&ctx->uring_lock);
1307 init_waitqueue_head(&ctx->cq_wait);
1308 spin_lock_init(&ctx->completion_lock);
1309 spin_lock_init(&ctx->timeout_lock);
1310 INIT_LIST_HEAD(&ctx->iopoll_list);
1311 INIT_LIST_HEAD(&ctx->defer_list);
1312 INIT_LIST_HEAD(&ctx->timeout_list);
1313 INIT_LIST_HEAD(&ctx->ltimeout_list);
1314 spin_lock_init(&ctx->rsrc_ref_lock);
1315 INIT_LIST_HEAD(&ctx->rsrc_ref_list);
1316 INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
1317 init_llist_head(&ctx->rsrc_put_llist);
1318 INIT_LIST_HEAD(&ctx->tctx_list);
1319 INIT_LIST_HEAD(&ctx->submit_state.free_list);
1320 INIT_LIST_HEAD(&ctx->locked_free_list);
1321 INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func);
1324 kfree(ctx->dummy_ubuf);
1325 kfree(ctx->cancel_hash);
1330 static void io_account_cq_overflow(struct io_ring_ctx *ctx)
1332 struct io_rings *r = ctx->rings;
1334 WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1);
1338 static bool req_need_defer(struct io_kiocb *req, u32 seq)
1340 if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
1341 struct io_ring_ctx *ctx = req->ctx;
1343 return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail;
1349 #define FFS_ASYNC_READ 0x1UL
1350 #define FFS_ASYNC_WRITE 0x2UL
1352 #define FFS_ISREG 0x4UL
1354 #define FFS_ISREG 0x0UL
1356 #define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)
1358 static inline bool io_req_ffs_set(struct io_kiocb *req)
1360 return IS_ENABLED(CONFIG_64BIT) && (req->flags & REQ_F_FIXED_FILE);
1363 static void io_req_track_inflight(struct io_kiocb *req)
1365 if (!(req->flags & REQ_F_INFLIGHT)) {
1366 req->flags |= REQ_F_INFLIGHT;
1367 atomic_inc(¤t->io_uring->inflight_tracked);
1371 static inline void io_unprep_linked_timeout(struct io_kiocb *req)
1373 req->flags &= ~REQ_F_LINK_TIMEOUT;
1376 static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req)
1378 if (WARN_ON_ONCE(!req->link))
1381 req->flags &= ~REQ_F_ARM_LTIMEOUT;
1382 req->flags |= REQ_F_LINK_TIMEOUT;
1384 /* linked timeouts should have two refs once prep'ed */
1385 io_req_set_refcount(req);
1386 __io_req_set_refcount(req->link, 2);
1390 static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
1392 if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT)))
1394 return __io_prep_linked_timeout(req);
1397 static void io_prep_async_work(struct io_kiocb *req)
1399 const struct io_op_def *def = &io_op_defs[req->opcode];
1400 struct io_ring_ctx *ctx = req->ctx;
1402 if (!(req->flags & REQ_F_CREDS)) {
1403 req->flags |= REQ_F_CREDS;
1404 req->creds = get_current_cred();
1407 req->work.list.next = NULL;
1408 req->work.flags = 0;
1409 if (req->flags & REQ_F_FORCE_ASYNC)
1410 req->work.flags |= IO_WQ_WORK_CONCURRENT;
1412 if (req->flags & REQ_F_ISREG) {
1413 if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
1414 io_wq_hash_work(&req->work, file_inode(req->file));
1415 } else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
1416 if (def->unbound_nonreg_file)
1417 req->work.flags |= IO_WQ_WORK_UNBOUND;
1420 switch (req->opcode) {
1421 case IORING_OP_SPLICE:
1423 if (!S_ISREG(file_inode(req->splice.file_in)->i_mode))
1424 req->work.flags |= IO_WQ_WORK_UNBOUND;
1429 static void io_prep_async_link(struct io_kiocb *req)
1431 struct io_kiocb *cur;
1433 if (req->flags & REQ_F_LINK_TIMEOUT) {
1434 struct io_ring_ctx *ctx = req->ctx;
1436 spin_lock(&ctx->completion_lock);
1437 io_for_each_link(cur, req)
1438 io_prep_async_work(cur);
1439 spin_unlock(&ctx->completion_lock);
1441 io_for_each_link(cur, req)
1442 io_prep_async_work(cur);
1446 static void io_queue_async_work(struct io_kiocb *req, bool *locked)
1448 struct io_ring_ctx *ctx = req->ctx;
1449 struct io_kiocb *link = io_prep_linked_timeout(req);
1450 struct io_uring_task *tctx = req->task->io_uring;
1452 /* must not take the lock, NULL it as a precaution */
1456 BUG_ON(!tctx->io_wq);
1458 /* init ->work of the whole link before punting */
1459 io_prep_async_link(req);
1462 * Not expected to happen, but if we do have a bug where this _can_
1463 * happen, catch it here and ensure the request is marked as
1464 * canceled. That will make io-wq go through the usual work cancel
1465 * procedure rather than attempt to run this request (or create a new
1468 if (WARN_ON_ONCE(!same_thread_group(req->task, current)))
1469 req->work.flags |= IO_WQ_WORK_CANCEL;
1471 trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
1472 &req->work, req->flags);
1473 io_wq_enqueue(tctx->io_wq, &req->work);
1475 io_queue_linked_timeout(link);
1478 static void io_kill_timeout(struct io_kiocb *req, int status)
1479 __must_hold(&req->ctx->completion_lock)
1480 __must_hold(&req->ctx->timeout_lock)
1482 struct io_timeout_data *io = req->async_data;
1484 if (hrtimer_try_to_cancel(&io->timer) != -1) {
1487 atomic_set(&req->ctx->cq_timeouts,
1488 atomic_read(&req->ctx->cq_timeouts) + 1);
1489 list_del_init(&req->timeout.list);
1490 io_cqring_fill_event(req->ctx, req->user_data, status, 0);
1491 io_put_req_deferred(req);
1495 static void io_queue_deferred(struct io_ring_ctx *ctx)
1497 while (!list_empty(&ctx->defer_list)) {
1498 struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
1499 struct io_defer_entry, list);
1501 if (req_need_defer(de->req, de->seq))
1503 list_del_init(&de->list);
1504 io_req_task_queue(de->req);
1509 static void io_flush_timeouts(struct io_ring_ctx *ctx)
1510 __must_hold(&ctx->completion_lock)
1512 u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
1514 spin_lock_irq(&ctx->timeout_lock);
1515 while (!list_empty(&ctx->timeout_list)) {
1516 u32 events_needed, events_got;
1517 struct io_kiocb *req = list_first_entry(&ctx->timeout_list,
1518 struct io_kiocb, timeout.list);
1520 if (io_is_timeout_noseq(req))
1524 * Since seq can easily wrap around over time, subtract
1525 * the last seq at which timeouts were flushed before comparing.
1526 * Assuming not more than 2^31-1 events have happened since,
1527 * these subtractions won't have wrapped, so we can check if
1528 * target is in [last_seq, current_seq] by comparing the two.
1530 events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
1531 events_got = seq - ctx->cq_last_tm_flush;
1532 if (events_got < events_needed)
1535 list_del_init(&req->timeout.list);
1536 io_kill_timeout(req, 0);
1538 ctx->cq_last_tm_flush = seq;
1539 spin_unlock_irq(&ctx->timeout_lock);
1542 static void __io_commit_cqring_flush(struct io_ring_ctx *ctx)
1544 if (ctx->off_timeout_used)
1545 io_flush_timeouts(ctx);
1546 if (ctx->drain_active)
1547 io_queue_deferred(ctx);
1550 static inline void io_commit_cqring(struct io_ring_ctx *ctx)
1552 if (unlikely(ctx->off_timeout_used || ctx->drain_active))
1553 __io_commit_cqring_flush(ctx);
1554 /* order cqe stores with ring update */
1555 smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
1558 static inline bool io_sqring_full(struct io_ring_ctx *ctx)
1560 struct io_rings *r = ctx->rings;
1562 return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
1565 static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
1567 return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
1570 static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx)
1572 struct io_rings *rings = ctx->rings;
1573 unsigned tail, mask = ctx->cq_entries - 1;
1576 * writes to the cq entry need to come after reading head; the
1577 * control dependency is enough as we're using WRITE_ONCE to
1580 if (__io_cqring_events(ctx) == ctx->cq_entries)
1583 tail = ctx->cached_cq_tail++;
1584 return &rings->cqes[tail & mask];
1587 static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
1589 if (likely(!ctx->cq_ev_fd))
1591 if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
1593 return !ctx->eventfd_async || io_wq_current_is_worker();
1597 * This should only get called when at least one event has been posted.
1598 * Some applications rely on the eventfd notification count only changing
1599 * IFF a new CQE has been added to the CQ ring. There's no depedency on
1600 * 1:1 relationship between how many times this function is called (and
1601 * hence the eventfd count) and number of CQEs posted to the CQ ring.
1603 static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
1606 * wake_up_all() may seem excessive, but io_wake_function() and
1607 * io_should_wake() handle the termination of the loop and only
1608 * wake as many waiters as we need to.
1610 if (wq_has_sleeper(&ctx->cq_wait))
1611 wake_up_all(&ctx->cq_wait);
1612 if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait))
1613 wake_up(&ctx->sq_data->wait);
1614 if (io_should_trigger_evfd(ctx))
1615 eventfd_signal(ctx->cq_ev_fd, 1);
1616 if (waitqueue_active(&ctx->poll_wait)) {
1617 wake_up_interruptible(&ctx->poll_wait);
1618 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
1622 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
1624 /* see waitqueue_active() comment */
1627 if (ctx->flags & IORING_SETUP_SQPOLL) {
1628 if (waitqueue_active(&ctx->cq_wait))
1629 wake_up_all(&ctx->cq_wait);
1631 if (io_should_trigger_evfd(ctx))
1632 eventfd_signal(ctx->cq_ev_fd, 1);
1633 if (waitqueue_active(&ctx->poll_wait)) {
1634 wake_up_interruptible(&ctx->poll_wait);
1635 kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN);
1639 /* Returns true if there are no backlogged entries after the flush */
1640 static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
1642 bool all_flushed, posted;
1644 if (!force && __io_cqring_events(ctx) == ctx->cq_entries)
1648 spin_lock(&ctx->completion_lock);
1649 while (!list_empty(&ctx->cq_overflow_list)) {
1650 struct io_uring_cqe *cqe = io_get_cqe(ctx);
1651 struct io_overflow_cqe *ocqe;
1655 ocqe = list_first_entry(&ctx->cq_overflow_list,
1656 struct io_overflow_cqe, list);
1658 memcpy(cqe, &ocqe->cqe, sizeof(*cqe));
1660 io_account_cq_overflow(ctx);
1663 list_del(&ocqe->list);
1667 all_flushed = list_empty(&ctx->cq_overflow_list);
1669 clear_bit(0, &ctx->check_cq_overflow);
1670 WRITE_ONCE(ctx->rings->sq_flags,
1671 ctx->rings->sq_flags & ~IORING_SQ_CQ_OVERFLOW);
1675 io_commit_cqring(ctx);
1676 spin_unlock(&ctx->completion_lock);
1678 io_cqring_ev_posted(ctx);
1682 static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx)
1686 if (test_bit(0, &ctx->check_cq_overflow)) {
1687 /* iopoll syncs against uring_lock, not completion_lock */
1688 if (ctx->flags & IORING_SETUP_IOPOLL)
1689 mutex_lock(&ctx->uring_lock);
1690 ret = __io_cqring_overflow_flush(ctx, false);
1691 if (ctx->flags & IORING_SETUP_IOPOLL)
1692 mutex_unlock(&ctx->uring_lock);
1698 /* must to be called somewhat shortly after putting a request */
1699 static inline void io_put_task(struct task_struct *task, int nr)
1701 struct io_uring_task *tctx = task->io_uring;
1703 if (likely(task == current)) {
1704 tctx->cached_refs += nr;
1706 percpu_counter_sub(&tctx->inflight, nr);
1707 if (unlikely(atomic_read(&tctx->in_idle)))
1708 wake_up(&tctx->wait);
1709 put_task_struct_many(task, nr);
1713 static void io_task_refs_refill(struct io_uring_task *tctx)
1715 unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR;
1717 percpu_counter_add(&tctx->inflight, refill);
1718 refcount_add(refill, ¤t->usage);
1719 tctx->cached_refs += refill;
1722 static inline void io_get_task_refs(int nr)
1724 struct io_uring_task *tctx = current->io_uring;
1726 tctx->cached_refs -= nr;
1727 if (unlikely(tctx->cached_refs < 0))
1728 io_task_refs_refill(tctx);
1731 static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data,
1732 long res, unsigned int cflags)
1734 struct io_overflow_cqe *ocqe;
1736 ocqe = kmalloc(sizeof(*ocqe), GFP_ATOMIC | __GFP_ACCOUNT);
1739 * If we're in ring overflow flush mode, or in task cancel mode,
1740 * or cannot allocate an overflow entry, then we need to drop it
1743 io_account_cq_overflow(ctx);
1746 if (list_empty(&ctx->cq_overflow_list)) {
1747 set_bit(0, &ctx->check_cq_overflow);
1748 WRITE_ONCE(ctx->rings->sq_flags,
1749 ctx->rings->sq_flags | IORING_SQ_CQ_OVERFLOW);
1752 ocqe->cqe.user_data = user_data;
1753 ocqe->cqe.res = res;
1754 ocqe->cqe.flags = cflags;
1755 list_add_tail(&ocqe->list, &ctx->cq_overflow_list);
1759 static inline bool __io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
1760 long res, unsigned int cflags)
1762 struct io_uring_cqe *cqe;
1764 trace_io_uring_complete(ctx, user_data, res, cflags);
1767 * If we can't get a cq entry, userspace overflowed the
1768 * submission (by quite a lot). Increment the overflow count in
1771 cqe = io_get_cqe(ctx);
1773 WRITE_ONCE(cqe->user_data, user_data);
1774 WRITE_ONCE(cqe->res, res);
1775 WRITE_ONCE(cqe->flags, cflags);
1778 return io_cqring_event_overflow(ctx, user_data, res, cflags);
1781 /* not as hot to bloat with inlining */
1782 static noinline bool io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
1783 long res, unsigned int cflags)
1785 return __io_cqring_fill_event(ctx, user_data, res, cflags);
1788 static void io_req_complete_post(struct io_kiocb *req, long res,
1789 unsigned int cflags)
1791 struct io_ring_ctx *ctx = req->ctx;
1793 spin_lock(&ctx->completion_lock);
1794 __io_cqring_fill_event(ctx, req->user_data, res, cflags);
1796 * If we're the last reference to this request, add to our locked
1799 if (req_ref_put_and_test(req)) {
1800 if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
1801 if (req->flags & IO_DISARM_MASK)
1802 io_disarm_next(req);
1804 io_req_task_queue(req->link);
1808 io_dismantle_req(req);
1809 io_put_task(req->task, 1);
1810 list_add(&req->inflight_entry, &ctx->locked_free_list);
1811 ctx->locked_free_nr++;
1813 if (!percpu_ref_tryget(&ctx->refs))
1816 io_commit_cqring(ctx);
1817 spin_unlock(&ctx->completion_lock);
1820 io_cqring_ev_posted(ctx);
1821 percpu_ref_put(&ctx->refs);
1825 static inline bool io_req_needs_clean(struct io_kiocb *req)
1827 return req->flags & IO_REQ_CLEAN_FLAGS;
1830 static void io_req_complete_state(struct io_kiocb *req, long res,
1831 unsigned int cflags)
1833 if (io_req_needs_clean(req))
1836 req->compl.cflags = cflags;
1837 req->flags |= REQ_F_COMPLETE_INLINE;
1840 static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
1841 long res, unsigned cflags)
1843 if (issue_flags & IO_URING_F_COMPLETE_DEFER)
1844 io_req_complete_state(req, res, cflags);
1846 io_req_complete_post(req, res, cflags);
1849 static inline void io_req_complete(struct io_kiocb *req, long res)
1851 __io_req_complete(req, 0, res, 0);
1854 static void io_req_complete_failed(struct io_kiocb *req, long res)
1857 io_req_complete_post(req, res, 0);
1860 static void io_req_complete_fail_submit(struct io_kiocb *req)
1863 * We don't submit, fail them all, for that replace hardlinks with
1864 * normal links. Extra REQ_F_LINK is tolerated.
1866 req->flags &= ~REQ_F_HARDLINK;
1867 req->flags |= REQ_F_LINK;
1868 io_req_complete_failed(req, req->result);
1872 * Don't initialise the fields below on every allocation, but do that in
1873 * advance and keep them valid across allocations.
1875 static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx)
1879 req->async_data = NULL;
1880 /* not necessary, but safer to zero */
1884 static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx,
1885 struct io_submit_state *state)
1887 spin_lock(&ctx->completion_lock);
1888 list_splice_init(&ctx->locked_free_list, &state->free_list);
1889 ctx->locked_free_nr = 0;
1890 spin_unlock(&ctx->completion_lock);
1893 /* Returns true IFF there are requests in the cache */
1894 static bool io_flush_cached_reqs(struct io_ring_ctx *ctx)
1896 struct io_submit_state *state = &ctx->submit_state;
1900 * If we have more than a batch's worth of requests in our IRQ side
1901 * locked cache, grab the lock and move them over to our submission
1904 if (READ_ONCE(ctx->locked_free_nr) > IO_COMPL_BATCH)
1905 io_flush_cached_locked_reqs(ctx, state);
1907 nr = state->free_reqs;
1908 while (!list_empty(&state->free_list)) {
1909 struct io_kiocb *req = list_first_entry(&state->free_list,
1910 struct io_kiocb, inflight_entry);
1912 list_del(&req->inflight_entry);
1913 state->reqs[nr++] = req;
1914 if (nr == ARRAY_SIZE(state->reqs))
1918 state->free_reqs = nr;
1923 * A request might get retired back into the request caches even before opcode
1924 * handlers and io_issue_sqe() are done with it, e.g. inline completion path.
1925 * Because of that, io_alloc_req() should be called only under ->uring_lock
1926 * and with extra caution to not get a request that is still worked on.
1928 static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
1929 __must_hold(&ctx->uring_lock)
1931 struct io_submit_state *state = &ctx->submit_state;
1932 gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
1935 BUILD_BUG_ON(ARRAY_SIZE(state->reqs) < IO_REQ_ALLOC_BATCH);
1937 if (likely(state->free_reqs || io_flush_cached_reqs(ctx)))
1940 ret = kmem_cache_alloc_bulk(req_cachep, gfp, IO_REQ_ALLOC_BATCH,
1944 * Bulk alloc is all-or-nothing. If we fail to get a batch,
1945 * retry single alloc to be on the safe side.
1947 if (unlikely(ret <= 0)) {
1948 state->reqs[0] = kmem_cache_alloc(req_cachep, gfp);
1949 if (!state->reqs[0])
1954 for (i = 0; i < ret; i++)
1955 io_preinit_req(state->reqs[i], ctx);
1956 state->free_reqs = ret;
1959 return state->reqs[state->free_reqs];
1962 static inline void io_put_file(struct file *file)
1968 static void io_dismantle_req(struct io_kiocb *req)
1970 unsigned int flags = req->flags;
1972 if (io_req_needs_clean(req))
1974 if (!(flags & REQ_F_FIXED_FILE))
1975 io_put_file(req->file);
1976 if (req->fixed_rsrc_refs)
1977 percpu_ref_put(req->fixed_rsrc_refs);
1978 if (req->async_data) {
1979 kfree(req->async_data);
1980 req->async_data = NULL;
1984 static void __io_free_req(struct io_kiocb *req)
1986 struct io_ring_ctx *ctx = req->ctx;
1988 io_dismantle_req(req);
1989 io_put_task(req->task, 1);
1991 spin_lock(&ctx->completion_lock);
1992 list_add(&req->inflight_entry, &ctx->locked_free_list);
1993 ctx->locked_free_nr++;
1994 spin_unlock(&ctx->completion_lock);
1996 percpu_ref_put(&ctx->refs);
1999 static inline void io_remove_next_linked(struct io_kiocb *req)
2001 struct io_kiocb *nxt = req->link;
2003 req->link = nxt->link;
2007 static bool io_kill_linked_timeout(struct io_kiocb *req)
2008 __must_hold(&req->ctx->completion_lock)
2009 __must_hold(&req->ctx->timeout_lock)
2011 struct io_kiocb *link = req->link;
2013 if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
2014 struct io_timeout_data *io = link->async_data;
2016 io_remove_next_linked(req);
2017 link->timeout.head = NULL;
2018 if (hrtimer_try_to_cancel(&io->timer) != -1) {
2019 list_del(&link->timeout.list);
2020 io_cqring_fill_event(link->ctx, link->user_data,
2022 io_put_req_deferred(link);
2029 static void io_fail_links(struct io_kiocb *req)
2030 __must_hold(&req->ctx->completion_lock)
2032 struct io_kiocb *nxt, *link = req->link;
2036 long res = -ECANCELED;
2038 if (link->flags & REQ_F_FAIL)
2044 trace_io_uring_fail_link(req, link);
2045 io_cqring_fill_event(link->ctx, link->user_data, res, 0);
2046 io_put_req_deferred(link);
2051 static bool io_disarm_next(struct io_kiocb *req)
2052 __must_hold(&req->ctx->completion_lock)
2054 bool posted = false;
2056 if (req->flags & REQ_F_ARM_LTIMEOUT) {
2057 struct io_kiocb *link = req->link;
2059 req->flags &= ~REQ_F_ARM_LTIMEOUT;
2060 if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
2061 io_remove_next_linked(req);
2062 io_cqring_fill_event(link->ctx, link->user_data,
2064 io_put_req_deferred(link);
2067 } else if (req->flags & REQ_F_LINK_TIMEOUT) {
2068 struct io_ring_ctx *ctx = req->ctx;
2070 spin_lock_irq(&ctx->timeout_lock);
2071 posted = io_kill_linked_timeout(req);
2072 spin_unlock_irq(&ctx->timeout_lock);
2074 if (unlikely((req->flags & REQ_F_FAIL) &&
2075 !(req->flags & REQ_F_HARDLINK))) {
2076 posted |= (req->link != NULL);
2082 static struct io_kiocb *__io_req_find_next(struct io_kiocb *req)
2084 struct io_kiocb *nxt;
2087 * If LINK is set, we have dependent requests in this chain. If we
2088 * didn't fail this request, queue the first one up, moving any other
2089 * dependencies to the next request. In case of failure, fail the rest
2092 if (req->flags & IO_DISARM_MASK) {
2093 struct io_ring_ctx *ctx = req->ctx;
2096 spin_lock(&ctx->completion_lock);
2097 posted = io_disarm_next(req);
2099 io_commit_cqring(req->ctx);
2100 spin_unlock(&ctx->completion_lock);
2102 io_cqring_ev_posted(ctx);
2109 static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
2111 if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK))))
2113 return __io_req_find_next(req);
2116 static void ctx_flush_and_put(struct io_ring_ctx *ctx, bool *locked)
2121 if (ctx->submit_state.compl_nr)
2122 io_submit_flush_completions(ctx);
2123 mutex_unlock(&ctx->uring_lock);
2126 percpu_ref_put(&ctx->refs);
2129 static void tctx_task_work(struct callback_head *cb)
2131 bool locked = false;
2132 struct io_ring_ctx *ctx = NULL;
2133 struct io_uring_task *tctx = container_of(cb, struct io_uring_task,
2137 struct io_wq_work_node *node;
2139 if (!tctx->task_list.first && locked && ctx->submit_state.compl_nr)
2140 io_submit_flush_completions(ctx);
2142 spin_lock_irq(&tctx->task_lock);
2143 node = tctx->task_list.first;
2144 INIT_WQ_LIST(&tctx->task_list);
2146 tctx->task_running = false;
2147 spin_unlock_irq(&tctx->task_lock);
2152 struct io_wq_work_node *next = node->next;
2153 struct io_kiocb *req = container_of(node, struct io_kiocb,
2156 if (req->ctx != ctx) {
2157 ctx_flush_and_put(ctx, &locked);
2159 /* if not contended, grab and improve batching */
2160 locked = mutex_trylock(&ctx->uring_lock);
2161 percpu_ref_get(&ctx->refs);
2163 req->io_task_work.func(req, &locked);
2170 ctx_flush_and_put(ctx, &locked);
2173 static void io_req_task_work_add(struct io_kiocb *req)
2175 struct task_struct *tsk = req->task;
2176 struct io_uring_task *tctx = tsk->io_uring;
2177 enum task_work_notify_mode notify;
2178 struct io_wq_work_node *node;
2179 unsigned long flags;
2182 WARN_ON_ONCE(!tctx);
2184 spin_lock_irqsave(&tctx->task_lock, flags);
2185 wq_list_add_tail(&req->io_task_work.node, &tctx->task_list);
2186 running = tctx->task_running;
2188 tctx->task_running = true;
2189 spin_unlock_irqrestore(&tctx->task_lock, flags);
2191 /* task_work already pending, we're done */
2196 * SQPOLL kernel thread doesn't need notification, just a wakeup. For
2197 * all other cases, use TWA_SIGNAL unconditionally to ensure we're
2198 * processing task_work. There's no reliable way to tell if TWA_RESUME
2201 notify = (req->ctx->flags & IORING_SETUP_SQPOLL) ? TWA_NONE : TWA_SIGNAL;
2202 if (!task_work_add(tsk, &tctx->task_work, notify)) {
2203 wake_up_process(tsk);
2207 spin_lock_irqsave(&tctx->task_lock, flags);
2208 tctx->task_running = false;
2209 node = tctx->task_list.first;
2210 INIT_WQ_LIST(&tctx->task_list);
2211 spin_unlock_irqrestore(&tctx->task_lock, flags);
2214 req = container_of(node, struct io_kiocb, io_task_work.node);
2216 if (llist_add(&req->io_task_work.fallback_node,
2217 &req->ctx->fallback_llist))
2218 schedule_delayed_work(&req->ctx->fallback_work, 1);
2222 static void io_req_task_cancel(struct io_kiocb *req, bool *locked)
2224 struct io_ring_ctx *ctx = req->ctx;
2226 /* not needed for normal modes, but SQPOLL depends on it */
2227 io_tw_lock(ctx, locked);
2228 io_req_complete_failed(req, req->result);
2231 static void io_req_task_submit(struct io_kiocb *req, bool *locked)
2233 struct io_ring_ctx *ctx = req->ctx;
2235 io_tw_lock(ctx, locked);
2236 /* req->task == current here, checking PF_EXITING is safe */
2237 if (likely(!(req->task->flags & PF_EXITING)))
2238 __io_queue_sqe(req);
2240 io_req_complete_failed(req, -EFAULT);
2243 static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
2246 req->io_task_work.func = io_req_task_cancel;
2247 io_req_task_work_add(req);
2250 static void io_req_task_queue(struct io_kiocb *req)
2252 req->io_task_work.func = io_req_task_submit;
2253 io_req_task_work_add(req);
2256 static void io_req_task_queue_reissue(struct io_kiocb *req)
2258 req->io_task_work.func = io_queue_async_work;
2259 io_req_task_work_add(req);
2262 static inline void io_queue_next(struct io_kiocb *req)
2264 struct io_kiocb *nxt = io_req_find_next(req);
2267 io_req_task_queue(nxt);
2270 static void io_free_req(struct io_kiocb *req)
2276 static void io_free_req_work(struct io_kiocb *req, bool *locked)
2282 struct task_struct *task;
2287 static inline void io_init_req_batch(struct req_batch *rb)
2294 static void io_req_free_batch_finish(struct io_ring_ctx *ctx,
2295 struct req_batch *rb)
2298 percpu_ref_put_many(&ctx->refs, rb->ctx_refs);
2300 io_put_task(rb->task, rb->task_refs);
2303 static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req,
2304 struct io_submit_state *state)
2307 io_dismantle_req(req);
2309 if (req->task != rb->task) {
2311 io_put_task(rb->task, rb->task_refs);
2312 rb->task = req->task;
2318 if (state->free_reqs != ARRAY_SIZE(state->reqs))
2319 state->reqs[state->free_reqs++] = req;
2321 list_add(&req->inflight_entry, &state->free_list);
2324 static void io_submit_flush_completions(struct io_ring_ctx *ctx)
2325 __must_hold(&ctx->uring_lock)
2327 struct io_submit_state *state = &ctx->submit_state;
2328 int i, nr = state->compl_nr;
2329 struct req_batch rb;
2331 spin_lock(&ctx->completion_lock);
2332 for (i = 0; i < nr; i++) {
2333 struct io_kiocb *req = state->compl_reqs[i];
2335 __io_cqring_fill_event(ctx, req->user_data, req->result,
2338 io_commit_cqring(ctx);
2339 spin_unlock(&ctx->completion_lock);
2340 io_cqring_ev_posted(ctx);
2342 io_init_req_batch(&rb);
2343 for (i = 0; i < nr; i++) {
2344 struct io_kiocb *req = state->compl_reqs[i];
2346 if (req_ref_put_and_test(req))
2347 io_req_free_batch(&rb, req, &ctx->submit_state);
2350 io_req_free_batch_finish(ctx, &rb);
2351 state->compl_nr = 0;
2355 * Drop reference to request, return next in chain (if there is one) if this
2356 * was the last reference to this request.
2358 static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
2360 struct io_kiocb *nxt = NULL;
2362 if (req_ref_put_and_test(req)) {
2363 nxt = io_req_find_next(req);
2369 static inline void io_put_req(struct io_kiocb *req)
2371 if (req_ref_put_and_test(req))
2375 static inline void io_put_req_deferred(struct io_kiocb *req)
2377 if (req_ref_put_and_test(req)) {
2378 req->io_task_work.func = io_free_req_work;
2379 io_req_task_work_add(req);
2383 static unsigned io_cqring_events(struct io_ring_ctx *ctx)
2385 /* See comment at the top of this file */
2387 return __io_cqring_events(ctx);
2390 static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
2392 struct io_rings *rings = ctx->rings;
2394 /* make sure SQ entry isn't read before tail */
2395 return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
2398 static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
2400 unsigned int cflags;
2402 cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
2403 cflags |= IORING_CQE_F_BUFFER;
2404 req->flags &= ~REQ_F_BUFFER_SELECTED;
2409 static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
2411 struct io_buffer *kbuf;
2413 if (likely(!(req->flags & REQ_F_BUFFER_SELECTED)))
2415 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
2416 return io_put_kbuf(req, kbuf);
2419 static inline bool io_run_task_work(void)
2421 if (test_thread_flag(TIF_NOTIFY_SIGNAL) || current->task_works) {
2422 __set_current_state(TASK_RUNNING);
2423 tracehook_notify_signal();
2431 * Find and free completed poll iocbs
2433 static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events,
2434 struct list_head *done)
2436 struct req_batch rb;
2437 struct io_kiocb *req;
2439 /* order with ->result store in io_complete_rw_iopoll() */
2442 io_init_req_batch(&rb);
2443 while (!list_empty(done)) {
2444 req = list_first_entry(done, struct io_kiocb, inflight_entry);
2445 list_del(&req->inflight_entry);
2447 if (READ_ONCE(req->result) == -EAGAIN &&
2448 !(req->flags & REQ_F_DONT_REISSUE)) {
2449 req->iopoll_completed = 0;
2450 io_req_task_queue_reissue(req);
2454 __io_cqring_fill_event(ctx, req->user_data, req->result,
2455 io_put_rw_kbuf(req));
2458 if (req_ref_put_and_test(req))
2459 io_req_free_batch(&rb, req, &ctx->submit_state);
2462 io_commit_cqring(ctx);
2463 io_cqring_ev_posted_iopoll(ctx);
2464 io_req_free_batch_finish(ctx, &rb);
2467 static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events,
2470 struct io_kiocb *req, *tmp;
2475 * Only spin for completions if we don't have multiple devices hanging
2476 * off our complete list, and we're under the requested amount.
2478 spin = !ctx->poll_multi_queue && *nr_events < min;
2480 list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) {
2481 struct kiocb *kiocb = &req->rw.kiocb;
2485 * Move completed and retryable entries to our local lists.
2486 * If we find a request that requires polling, break out
2487 * and complete those lists first, if we have entries there.
2489 if (READ_ONCE(req->iopoll_completed)) {
2490 list_move_tail(&req->inflight_entry, &done);
2493 if (!list_empty(&done))
2496 ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin);
2497 if (unlikely(ret < 0))
2502 /* iopoll may have completed current req */
2503 if (READ_ONCE(req->iopoll_completed))
2504 list_move_tail(&req->inflight_entry, &done);
2507 if (!list_empty(&done))
2508 io_iopoll_complete(ctx, nr_events, &done);
2514 * We can't just wait for polled events to come to us, we have to actively
2515 * find and complete them.
2517 static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
2519 if (!(ctx->flags & IORING_SETUP_IOPOLL))
2522 mutex_lock(&ctx->uring_lock);
2523 while (!list_empty(&ctx->iopoll_list)) {
2524 unsigned int nr_events = 0;
2526 io_do_iopoll(ctx, &nr_events, 0);
2528 /* let it sleep and repeat later if can't complete a request */
2532 * Ensure we allow local-to-the-cpu processing to take place,
2533 * in this case we need to ensure that we reap all events.
2534 * Also let task_work, etc. to progress by releasing the mutex
2536 if (need_resched()) {
2537 mutex_unlock(&ctx->uring_lock);
2539 mutex_lock(&ctx->uring_lock);
2542 mutex_unlock(&ctx->uring_lock);
2545 static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
2547 unsigned int nr_events = 0;
2551 * We disallow the app entering submit/complete with polling, but we
2552 * still need to lock the ring to prevent racing with polled issue
2553 * that got punted to a workqueue.
2555 mutex_lock(&ctx->uring_lock);
2557 * Don't enter poll loop if we already have events pending.
2558 * If we do, we can potentially be spinning for commands that
2559 * already triggered a CQE (eg in error).
2561 if (test_bit(0, &ctx->check_cq_overflow))
2562 __io_cqring_overflow_flush(ctx, false);
2563 if (io_cqring_events(ctx))
2567 * If a submit got punted to a workqueue, we can have the
2568 * application entering polling for a command before it gets
2569 * issued. That app will hold the uring_lock for the duration
2570 * of the poll right here, so we need to take a breather every
2571 * now and then to ensure that the issue has a chance to add
2572 * the poll to the issued list. Otherwise we can spin here
2573 * forever, while the workqueue is stuck trying to acquire the
2576 if (list_empty(&ctx->iopoll_list)) {
2577 u32 tail = ctx->cached_cq_tail;
2579 mutex_unlock(&ctx->uring_lock);
2581 mutex_lock(&ctx->uring_lock);
2583 /* some requests don't go through iopoll_list */
2584 if (tail != ctx->cached_cq_tail ||
2585 list_empty(&ctx->iopoll_list))
2588 ret = io_do_iopoll(ctx, &nr_events, min);
2589 } while (!ret && nr_events < min && !need_resched());
2591 mutex_unlock(&ctx->uring_lock);
2595 static void kiocb_end_write(struct io_kiocb *req)
2598 * Tell lockdep we inherited freeze protection from submission
2601 if (req->flags & REQ_F_ISREG) {
2602 struct super_block *sb = file_inode(req->file)->i_sb;
2604 __sb_writers_acquired(sb, SB_FREEZE_WRITE);
2610 static bool io_resubmit_prep(struct io_kiocb *req)
2612 struct io_async_rw *rw = req->async_data;
2615 return !io_req_prep_async(req);
2616 /* may have left rw->iter inconsistent on -EIOCBQUEUED */
2617 iov_iter_revert(&rw->iter, req->result - iov_iter_count(&rw->iter));
2621 static bool io_rw_should_reissue(struct io_kiocb *req)
2623 umode_t mode = file_inode(req->file)->i_mode;
2624 struct io_ring_ctx *ctx = req->ctx;
2626 if (!S_ISBLK(mode) && !S_ISREG(mode))
2628 if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
2629 !(ctx->flags & IORING_SETUP_IOPOLL)))
2632 * If ref is dying, we might be running poll reap from the exit work.
2633 * Don't attempt to reissue from that path, just let it fail with
2636 if (percpu_ref_is_dying(&ctx->refs))
2639 * Play it safe and assume not safe to re-import and reissue if we're
2640 * not in the original thread group (or in task context).
2642 if (!same_thread_group(req->task, current) || !in_task())
2647 static bool io_resubmit_prep(struct io_kiocb *req)
2651 static bool io_rw_should_reissue(struct io_kiocb *req)
2657 static bool __io_complete_rw_common(struct io_kiocb *req, long res)
2659 if (req->rw.kiocb.ki_flags & IOCB_WRITE)
2660 kiocb_end_write(req);
2661 if (res != req->result) {
2662 if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
2663 io_rw_should_reissue(req)) {
2664 req->flags |= REQ_F_REISSUE;
2673 static void io_req_task_complete(struct io_kiocb *req, bool *locked)
2675 unsigned int cflags = io_put_rw_kbuf(req);
2676 long res = req->result;
2679 struct io_ring_ctx *ctx = req->ctx;
2680 struct io_submit_state *state = &ctx->submit_state;
2682 io_req_complete_state(req, res, cflags);
2683 state->compl_reqs[state->compl_nr++] = req;
2684 if (state->compl_nr == ARRAY_SIZE(state->compl_reqs))
2685 io_submit_flush_completions(ctx);
2687 io_req_complete_post(req, res, cflags);
2691 static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
2692 unsigned int issue_flags)
2694 if (__io_complete_rw_common(req, res))
2696 __io_req_complete(req, issue_flags, req->result, io_put_rw_kbuf(req));
2699 static void io_complete_rw(struct kiocb *kiocb, long res, long res2)
2701 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2703 if (__io_complete_rw_common(req, res))
2706 req->io_task_work.func = io_req_task_complete;
2707 io_req_task_work_add(req);
2710 static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)
2712 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2714 if (kiocb->ki_flags & IOCB_WRITE)
2715 kiocb_end_write(req);
2716 if (unlikely(res != req->result)) {
2717 if (!(res == -EAGAIN && io_rw_should_reissue(req) &&
2718 io_resubmit_prep(req))) {
2720 req->flags |= REQ_F_DONT_REISSUE;
2724 WRITE_ONCE(req->result, res);
2725 /* order with io_iopoll_complete() checking ->result */
2727 WRITE_ONCE(req->iopoll_completed, 1);
2731 * After the iocb has been issued, it's safe to be found on the poll list.
2732 * Adding the kiocb to the list AFTER submission ensures that we don't
2733 * find it from a io_do_iopoll() thread before the issuer is done
2734 * accessing the kiocb cookie.
2736 static void io_iopoll_req_issued(struct io_kiocb *req)
2738 struct io_ring_ctx *ctx = req->ctx;
2739 const bool in_async = io_wq_current_is_worker();
2741 /* workqueue context doesn't hold uring_lock, grab it now */
2742 if (unlikely(in_async))
2743 mutex_lock(&ctx->uring_lock);
2746 * Track whether we have multiple files in our lists. This will impact
2747 * how we do polling eventually, not spinning if we're on potentially
2748 * different devices.
2750 if (list_empty(&ctx->iopoll_list)) {
2751 ctx->poll_multi_queue = false;
2752 } else if (!ctx->poll_multi_queue) {
2753 struct io_kiocb *list_req;
2754 unsigned int queue_num0, queue_num1;
2756 list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb,
2759 if (list_req->file != req->file) {
2760 ctx->poll_multi_queue = true;
2762 queue_num0 = blk_qc_t_to_queue_num(list_req->rw.kiocb.ki_cookie);
2763 queue_num1 = blk_qc_t_to_queue_num(req->rw.kiocb.ki_cookie);
2764 if (queue_num0 != queue_num1)
2765 ctx->poll_multi_queue = true;
2770 * For fast devices, IO may have already completed. If it has, add
2771 * it to the front so we find it first.
2773 if (READ_ONCE(req->iopoll_completed))
2774 list_add(&req->inflight_entry, &ctx->iopoll_list);
2776 list_add_tail(&req->inflight_entry, &ctx->iopoll_list);
2778 if (unlikely(in_async)) {
2780 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
2781 * in sq thread task context or in io worker task context. If
2782 * current task context is sq thread, we don't need to check
2783 * whether should wake up sq thread.
2785 if ((ctx->flags & IORING_SETUP_SQPOLL) &&
2786 wq_has_sleeper(&ctx->sq_data->wait))
2787 wake_up(&ctx->sq_data->wait);
2789 mutex_unlock(&ctx->uring_lock);
2793 static bool io_bdev_nowait(struct block_device *bdev)
2795 return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
2799 * If we tracked the file through the SCM inflight mechanism, we could support
2800 * any file. For now, just ensure that anything potentially problematic is done
2803 static bool __io_file_supports_nowait(struct file *file, int rw)
2805 umode_t mode = file_inode(file)->i_mode;
2807 if (S_ISBLK(mode)) {
2808 if (IS_ENABLED(CONFIG_BLOCK) &&
2809 io_bdev_nowait(I_BDEV(file->f_mapping->host)))
2815 if (S_ISREG(mode)) {
2816 if (IS_ENABLED(CONFIG_BLOCK) &&
2817 io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
2818 file->f_op != &io_uring_fops)
2823 /* any ->read/write should understand O_NONBLOCK */
2824 if (file->f_flags & O_NONBLOCK)
2827 if (!(file->f_mode & FMODE_NOWAIT))
2831 return file->f_op->read_iter != NULL;
2833 return file->f_op->write_iter != NULL;
2836 static bool io_file_supports_nowait(struct io_kiocb *req, int rw)
2838 if (rw == READ && (req->flags & REQ_F_NOWAIT_READ))
2840 else if (rw == WRITE && (req->flags & REQ_F_NOWAIT_WRITE))
2843 return __io_file_supports_nowait(req->file, rw);
2846 static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
2848 struct io_ring_ctx *ctx = req->ctx;
2849 struct kiocb *kiocb = &req->rw.kiocb;
2850 struct file *file = req->file;
2854 if (!io_req_ffs_set(req) && S_ISREG(file_inode(file)->i_mode))
2855 req->flags |= REQ_F_ISREG;
2857 kiocb->ki_pos = READ_ONCE(sqe->off);
2858 if (kiocb->ki_pos == -1 && !(file->f_mode & FMODE_STREAM)) {
2859 req->flags |= REQ_F_CUR_POS;
2860 kiocb->ki_pos = file->f_pos;
2862 kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));
2863 kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
2864 ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
2868 /* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */
2869 if ((kiocb->ki_flags & IOCB_NOWAIT) || (file->f_flags & O_NONBLOCK))
2870 req->flags |= REQ_F_NOWAIT;
2872 ioprio = READ_ONCE(sqe->ioprio);
2874 ret = ioprio_check_cap(ioprio);
2878 kiocb->ki_ioprio = ioprio;
2880 kiocb->ki_ioprio = get_current_ioprio();
2882 if (ctx->flags & IORING_SETUP_IOPOLL) {
2883 if (!(kiocb->ki_flags & IOCB_DIRECT) ||
2884 !kiocb->ki_filp->f_op->iopoll)
2887 kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE;
2888 kiocb->ki_complete = io_complete_rw_iopoll;
2889 req->iopoll_completed = 0;
2891 if (kiocb->ki_flags & IOCB_HIPRI)
2893 kiocb->ki_complete = io_complete_rw;
2896 if (req->opcode == IORING_OP_READ_FIXED ||
2897 req->opcode == IORING_OP_WRITE_FIXED) {
2899 io_req_set_rsrc_node(req);
2902 req->rw.addr = READ_ONCE(sqe->addr);
2903 req->rw.len = READ_ONCE(sqe->len);
2904 req->buf_index = READ_ONCE(sqe->buf_index);
2908 static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
2914 case -ERESTARTNOINTR:
2915 case -ERESTARTNOHAND:
2916 case -ERESTART_RESTARTBLOCK:
2918 * We can't just restart the syscall, since previously
2919 * submitted sqes may already be in progress. Just fail this
2925 kiocb->ki_complete(kiocb, ret, 0);
2929 static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
2930 unsigned int issue_flags)
2932 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
2933 struct io_async_rw *io = req->async_data;
2934 bool check_reissue = kiocb->ki_complete == io_complete_rw;
2936 /* add previously done IO, if any */
2937 if (io && io->bytes_done > 0) {
2939 ret = io->bytes_done;
2941 ret += io->bytes_done;
2944 if (req->flags & REQ_F_CUR_POS)
2945 req->file->f_pos = kiocb->ki_pos;
2946 if (ret >= 0 && check_reissue)
2947 __io_complete_rw(req, ret, 0, issue_flags);
2949 io_rw_done(kiocb, ret);
2951 if (check_reissue && (req->flags & REQ_F_REISSUE)) {
2952 req->flags &= ~REQ_F_REISSUE;
2953 if (io_resubmit_prep(req)) {
2954 io_req_task_queue_reissue(req);
2957 __io_req_complete(req, issue_flags, ret,
2958 io_put_rw_kbuf(req));
2963 static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
2964 struct io_mapped_ubuf *imu)
2966 size_t len = req->rw.len;
2967 u64 buf_end, buf_addr = req->rw.addr;
2970 if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
2972 /* not inside the mapped region */
2973 if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
2977 * May not be a start of buffer, set size appropriately
2978 * and advance us to the beginning.
2980 offset = buf_addr - imu->ubuf;
2981 iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
2985 * Don't use iov_iter_advance() here, as it's really slow for
2986 * using the latter parts of a big fixed buffer - it iterates
2987 * over each segment manually. We can cheat a bit here, because
2990 * 1) it's a BVEC iter, we set it up
2991 * 2) all bvecs are PAGE_SIZE in size, except potentially the
2992 * first and last bvec
2994 * So just find our index, and adjust the iterator afterwards.
2995 * If the offset is within the first bvec (or the whole first
2996 * bvec, just use iov_iter_advance(). This makes it easier
2997 * since we can just skip the first segment, which may not
2998 * be PAGE_SIZE aligned.
3000 const struct bio_vec *bvec = imu->bvec;
3002 if (offset <= bvec->bv_len) {
3003 iov_iter_advance(iter, offset);
3005 unsigned long seg_skip;
3007 /* skip first vec */
3008 offset -= bvec->bv_len;
3009 seg_skip = 1 + (offset >> PAGE_SHIFT);
3011 iter->bvec = bvec + seg_skip;
3012 iter->nr_segs -= seg_skip;
3013 iter->count -= bvec->bv_len + offset;
3014 iter->iov_offset = offset & ~PAGE_MASK;
3021 static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
3023 struct io_ring_ctx *ctx = req->ctx;
3024 struct io_mapped_ubuf *imu = req->imu;
3025 u16 index, buf_index = req->buf_index;
3028 if (unlikely(buf_index >= ctx->nr_user_bufs))
3030 index = array_index_nospec(buf_index, ctx->nr_user_bufs);
3031 imu = READ_ONCE(ctx->user_bufs[index]);
3034 return __io_import_fixed(req, rw, iter, imu);
3037 static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
3040 mutex_unlock(&ctx->uring_lock);
3043 static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
3046 * "Normal" inline submissions always hold the uring_lock, since we
3047 * grab it from the system call. Same is true for the SQPOLL offload.
3048 * The only exception is when we've detached the request and issue it
3049 * from an async worker thread, grab the lock for that case.
3052 mutex_lock(&ctx->uring_lock);
3055 static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
3056 int bgid, struct io_buffer *kbuf,
3059 struct io_buffer *head;
3061 if (req->flags & REQ_F_BUFFER_SELECTED)
3064 io_ring_submit_lock(req->ctx, needs_lock);
3066 lockdep_assert_held(&req->ctx->uring_lock);
3068 head = xa_load(&req->ctx->io_buffers, bgid);
3070 if (!list_empty(&head->list)) {
3071 kbuf = list_last_entry(&head->list, struct io_buffer,
3073 list_del(&kbuf->list);
3076 xa_erase(&req->ctx->io_buffers, bgid);
3078 if (*len > kbuf->len)
3081 kbuf = ERR_PTR(-ENOBUFS);
3084 io_ring_submit_unlock(req->ctx, needs_lock);
3089 static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
3092 struct io_buffer *kbuf;
3095 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
3096 bgid = req->buf_index;
3097 kbuf = io_buffer_select(req, len, bgid, kbuf, needs_lock);
3100 req->rw.addr = (u64) (unsigned long) kbuf;
3101 req->flags |= REQ_F_BUFFER_SELECTED;
3102 return u64_to_user_ptr(kbuf->addr);
3105 #ifdef CONFIG_COMPAT
3106 static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
3109 struct compat_iovec __user *uiov;
3110 compat_ssize_t clen;
3114 uiov = u64_to_user_ptr(req->rw.addr);
3115 if (!access_ok(uiov, sizeof(*uiov)))
3117 if (__get_user(clen, &uiov->iov_len))
3123 buf = io_rw_buffer_select(req, &len, needs_lock);
3125 return PTR_ERR(buf);
3126 iov[0].iov_base = buf;
3127 iov[0].iov_len = (compat_size_t) len;
3132 static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
3135 struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
3139 if (copy_from_user(iov, uiov, sizeof(*uiov)))
3142 len = iov[0].iov_len;
3145 buf = io_rw_buffer_select(req, &len, needs_lock);
3147 return PTR_ERR(buf);
3148 iov[0].iov_base = buf;
3149 iov[0].iov_len = len;
3153 static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
3156 if (req->flags & REQ_F_BUFFER_SELECTED) {
3157 struct io_buffer *kbuf;
3159 kbuf = (struct io_buffer *) (unsigned long) req->rw.addr;
3160 iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
3161 iov[0].iov_len = kbuf->len;
3164 if (req->rw.len != 1)
3167 #ifdef CONFIG_COMPAT
3168 if (req->ctx->compat)
3169 return io_compat_import(req, iov, needs_lock);
3172 return __io_iov_buffer_select(req, iov, needs_lock);
3175 static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec,
3176 struct iov_iter *iter, bool needs_lock)
3178 void __user *buf = u64_to_user_ptr(req->rw.addr);
3179 size_t sqe_len = req->rw.len;
3180 u8 opcode = req->opcode;
3183 if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
3185 return io_import_fixed(req, rw, iter);
3188 /* buffer index only valid with fixed read/write, or buffer select */
3189 if (req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT))
3192 if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
3193 if (req->flags & REQ_F_BUFFER_SELECT) {
3194 buf = io_rw_buffer_select(req, &sqe_len, needs_lock);
3196 return PTR_ERR(buf);
3197 req->rw.len = sqe_len;
3200 ret = import_single_range(rw, buf, sqe_len, *iovec, iter);
3205 if (req->flags & REQ_F_BUFFER_SELECT) {
3206 ret = io_iov_buffer_select(req, *iovec, needs_lock);
3208 iov_iter_init(iter, rw, *iovec, 1, (*iovec)->iov_len);
3213 return __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, iovec, iter,
3217 static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
3219 return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
3223 * For files that don't have ->read_iter() and ->write_iter(), handle them
3224 * by looping over ->read() or ->write() manually.
3226 static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
3228 struct kiocb *kiocb = &req->rw.kiocb;
3229 struct file *file = req->file;
3233 * Don't support polled IO through this interface, and we can't
3234 * support non-blocking either. For the latter, this just causes
3235 * the kiocb to be handled from an async context.
3237 if (kiocb->ki_flags & IOCB_HIPRI)
3239 if (kiocb->ki_flags & IOCB_NOWAIT)
3242 while (iov_iter_count(iter)) {
3246 if (!iov_iter_is_bvec(iter)) {
3247 iovec = iov_iter_iovec(iter);
3249 iovec.iov_base = u64_to_user_ptr(req->rw.addr);
3250 iovec.iov_len = req->rw.len;
3254 nr = file->f_op->read(file, iovec.iov_base,
3255 iovec.iov_len, io_kiocb_ppos(kiocb));
3257 nr = file->f_op->write(file, iovec.iov_base,
3258 iovec.iov_len, io_kiocb_ppos(kiocb));
3267 if (nr != iovec.iov_len)
3271 iov_iter_advance(iter, nr);
3277 static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
3278 const struct iovec *fast_iov, struct iov_iter *iter)
3280 struct io_async_rw *rw = req->async_data;
3282 memcpy(&rw->iter, iter, sizeof(*iter));
3283 rw->free_iovec = iovec;
3285 /* can only be fixed buffers, no need to do anything */
3286 if (iov_iter_is_bvec(iter))
3289 unsigned iov_off = 0;
3291 rw->iter.iov = rw->fast_iov;
3292 if (iter->iov != fast_iov) {
3293 iov_off = iter->iov - fast_iov;
3294 rw->iter.iov += iov_off;
3296 if (rw->fast_iov != fast_iov)
3297 memcpy(rw->fast_iov + iov_off, fast_iov + iov_off,
3298 sizeof(struct iovec) * iter->nr_segs);
3300 req->flags |= REQ_F_NEED_CLEANUP;
3304 static inline int io_alloc_async_data(struct io_kiocb *req)
3306 WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
3307 req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
3308 return req->async_data == NULL;
3311 static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
3312 const struct iovec *fast_iov,
3313 struct iov_iter *iter, bool force)
3315 if (!force && !io_op_defs[req->opcode].needs_async_setup)
3317 if (!req->async_data) {
3318 if (io_alloc_async_data(req)) {
3323 io_req_map_rw(req, iovec, fast_iov, iter);
3328 static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
3330 struct io_async_rw *iorw = req->async_data;
3331 struct iovec *iov = iorw->fast_iov;
3334 ret = io_import_iovec(rw, req, &iov, &iorw->iter, false);
3335 if (unlikely(ret < 0))
3338 iorw->bytes_done = 0;
3339 iorw->free_iovec = iov;
3341 req->flags |= REQ_F_NEED_CLEANUP;
3345 static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3347 if (unlikely(!(req->file->f_mode & FMODE_READ)))
3349 return io_prep_rw(req, sqe);
3353 * This is our waitqueue callback handler, registered through lock_page_async()
3354 * when we initially tried to do the IO with the iocb armed our waitqueue.
3355 * This gets called when the page is unlocked, and we generally expect that to
3356 * happen when the page IO is completed and the page is now uptodate. This will
3357 * queue a task_work based retry of the operation, attempting to copy the data
3358 * again. If the latter fails because the page was NOT uptodate, then we will
3359 * do a thread based blocking retry of the operation. That's the unexpected
3362 static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
3363 int sync, void *arg)
3365 struct wait_page_queue *wpq;
3366 struct io_kiocb *req = wait->private;
3367 struct wait_page_key *key = arg;
3369 wpq = container_of(wait, struct wait_page_queue, wait);
3371 if (!wake_page_match(wpq, key))
3374 req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
3375 list_del_init(&wait->entry);
3376 io_req_task_queue(req);
3381 * This controls whether a given IO request should be armed for async page
3382 * based retry. If we return false here, the request is handed to the async
3383 * worker threads for retry. If we're doing buffered reads on a regular file,
3384 * we prepare a private wait_page_queue entry and retry the operation. This
3385 * will either succeed because the page is now uptodate and unlocked, or it
3386 * will register a callback when the page is unlocked at IO completion. Through
3387 * that callback, io_uring uses task_work to setup a retry of the operation.
3388 * That retry will attempt the buffered read again. The retry will generally
3389 * succeed, or in rare cases where it fails, we then fall back to using the
3390 * async worker threads for a blocking retry.
3392 static bool io_rw_should_retry(struct io_kiocb *req)
3394 struct io_async_rw *rw = req->async_data;
3395 struct wait_page_queue *wait = &rw->wpq;
3396 struct kiocb *kiocb = &req->rw.kiocb;
3398 /* never retry for NOWAIT, we just complete with -EAGAIN */
3399 if (req->flags & REQ_F_NOWAIT)
3402 /* Only for buffered IO */
3403 if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
3407 * just use poll if we can, and don't attempt if the fs doesn't
3408 * support callback based unlocks
3410 if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
3413 wait->wait.func = io_async_buf_func;
3414 wait->wait.private = req;
3415 wait->wait.flags = 0;
3416 INIT_LIST_HEAD(&wait->wait.entry);
3417 kiocb->ki_flags |= IOCB_WAITQ;
3418 kiocb->ki_flags &= ~IOCB_NOWAIT;
3419 kiocb->ki_waitq = wait;
3423 static inline int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
3425 if (req->file->f_op->read_iter)
3426 return call_read_iter(req->file, &req->rw.kiocb, iter);
3427 else if (req->file->f_op->read)
3428 return loop_rw_iter(READ, req, iter);
3433 static bool need_read_all(struct io_kiocb *req)
3435 return req->flags & REQ_F_ISREG ||
3436 S_ISBLK(file_inode(req->file)->i_mode);
3439 static int io_read(struct io_kiocb *req, unsigned int issue_flags)
3441 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
3442 struct kiocb *kiocb = &req->rw.kiocb;
3443 struct iov_iter __iter, *iter = &__iter;
3444 struct io_async_rw *rw = req->async_data;
3445 ssize_t io_size, ret, ret2;
3446 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3452 ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock);
3456 io_size = iov_iter_count(iter);
3457 req->result = io_size;
3459 /* Ensure we clear previously set non-block flag */
3460 if (!force_nonblock)
3461 kiocb->ki_flags &= ~IOCB_NOWAIT;
3463 kiocb->ki_flags |= IOCB_NOWAIT;
3465 /* If the file doesn't support async, just async punt */
3466 if (force_nonblock && !io_file_supports_nowait(req, READ)) {
3467 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
3468 return ret ?: -EAGAIN;
3471 ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), io_size);
3472 if (unlikely(ret)) {
3477 ret = io_iter_do_read(req, iter);
3479 if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
3480 req->flags &= ~REQ_F_REISSUE;
3481 /* IOPOLL retry should happen for io-wq threads */
3482 if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
3484 /* no retry on NONBLOCK nor RWF_NOWAIT */
3485 if (req->flags & REQ_F_NOWAIT)
3487 /* some cases will consume bytes even on error returns */
3488 iov_iter_revert(iter, io_size - iov_iter_count(iter));
3490 } else if (ret == -EIOCBQUEUED) {
3492 } else if (ret <= 0 || ret == io_size || !force_nonblock ||
3493 (req->flags & REQ_F_NOWAIT) || !need_read_all(req)) {
3494 /* read all, failed, already did sync or don't want to retry */
3498 ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true);
3503 rw = req->async_data;
3504 /* now use our persistent iterator, if we aren't already */
3509 rw->bytes_done += ret;
3510 /* if we can retry, do so with the callbacks armed */
3511 if (!io_rw_should_retry(req)) {
3512 kiocb->ki_flags &= ~IOCB_WAITQ;
3517 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
3518 * we get -EIOCBQUEUED, then we'll get a notification when the
3519 * desired page gets unlocked. We can also get a partial read
3520 * here, and if we do, then just retry at the new offset.
3522 ret = io_iter_do_read(req, iter);
3523 if (ret == -EIOCBQUEUED)
3525 /* we got some bytes, but not all. retry. */
3526 kiocb->ki_flags &= ~IOCB_WAITQ;
3527 } while (ret > 0 && ret < io_size);
3529 kiocb_done(kiocb, ret, issue_flags);
3531 /* it's faster to check here then delegate to kfree */
3537 static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3539 if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
3541 return io_prep_rw(req, sqe);
3544 static int io_write(struct io_kiocb *req, unsigned int issue_flags)
3546 struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs;
3547 struct kiocb *kiocb = &req->rw.kiocb;
3548 struct iov_iter __iter, *iter = &__iter;
3549 struct io_async_rw *rw = req->async_data;
3550 ssize_t ret, ret2, io_size;
3551 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
3557 ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock);
3561 io_size = iov_iter_count(iter);
3562 req->result = io_size;
3564 /* Ensure we clear previously set non-block flag */
3565 if (!force_nonblock)
3566 kiocb->ki_flags &= ~IOCB_NOWAIT;
3568 kiocb->ki_flags |= IOCB_NOWAIT;
3570 /* If the file doesn't support async, just async punt */
3571 if (force_nonblock && !io_file_supports_nowait(req, WRITE))
3574 /* file path doesn't support NOWAIT for non-direct_IO */
3575 if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
3576 (req->flags & REQ_F_ISREG))
3579 ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), io_size);
3584 * Open-code file_start_write here to grab freeze protection,
3585 * which will be released by another thread in
3586 * io_complete_rw(). Fool lockdep by telling it the lock got
3587 * released so that it doesn't complain about the held lock when
3588 * we return to userspace.
3590 if (req->flags & REQ_F_ISREG) {
3591 sb_start_write(file_inode(req->file)->i_sb);
3592 __sb_writers_release(file_inode(req->file)->i_sb,
3595 kiocb->ki_flags |= IOCB_WRITE;
3597 if (req->file->f_op->write_iter)
3598 ret2 = call_write_iter(req->file, kiocb, iter);
3599 else if (req->file->f_op->write)
3600 ret2 = loop_rw_iter(WRITE, req, iter);
3604 if (req->flags & REQ_F_REISSUE) {
3605 req->flags &= ~REQ_F_REISSUE;
3610 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
3611 * retry them without IOCB_NOWAIT.
3613 if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
3615 /* no retry on NONBLOCK nor RWF_NOWAIT */
3616 if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
3618 if (!force_nonblock || ret2 != -EAGAIN) {
3619 /* IOPOLL retry should happen for io-wq threads */
3620 if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN)
3623 kiocb_done(kiocb, ret2, issue_flags);
3626 /* some cases will consume bytes even on error returns */
3627 iov_iter_revert(iter, io_size - iov_iter_count(iter));
3628 ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false);
3629 return ret ?: -EAGAIN;
3632 /* it's reportedly faster than delegating the null check to kfree() */
3638 static int io_renameat_prep(struct io_kiocb *req,
3639 const struct io_uring_sqe *sqe)
3641 struct io_rename *ren = &req->rename;
3642 const char __user *oldf, *newf;
3644 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3646 if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
3648 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3651 ren->old_dfd = READ_ONCE(sqe->fd);
3652 oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
3653 newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3654 ren->new_dfd = READ_ONCE(sqe->len);
3655 ren->flags = READ_ONCE(sqe->rename_flags);
3657 ren->oldpath = getname(oldf);
3658 if (IS_ERR(ren->oldpath))
3659 return PTR_ERR(ren->oldpath);
3661 ren->newpath = getname(newf);
3662 if (IS_ERR(ren->newpath)) {
3663 putname(ren->oldpath);
3664 return PTR_ERR(ren->newpath);
3667 req->flags |= REQ_F_NEED_CLEANUP;
3671 static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
3673 struct io_rename *ren = &req->rename;
3676 if (issue_flags & IO_URING_F_NONBLOCK)
3679 ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
3680 ren->newpath, ren->flags);
3682 req->flags &= ~REQ_F_NEED_CLEANUP;
3685 io_req_complete(req, ret);
3689 static int io_unlinkat_prep(struct io_kiocb *req,
3690 const struct io_uring_sqe *sqe)
3692 struct io_unlink *un = &req->unlink;
3693 const char __user *fname;
3695 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3697 if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
3700 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3703 un->dfd = READ_ONCE(sqe->fd);
3705 un->flags = READ_ONCE(sqe->unlink_flags);
3706 if (un->flags & ~AT_REMOVEDIR)
3709 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
3710 un->filename = getname(fname);
3711 if (IS_ERR(un->filename))
3712 return PTR_ERR(un->filename);
3714 req->flags |= REQ_F_NEED_CLEANUP;
3718 static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
3720 struct io_unlink *un = &req->unlink;
3723 if (issue_flags & IO_URING_F_NONBLOCK)
3726 if (un->flags & AT_REMOVEDIR)
3727 ret = do_rmdir(un->dfd, un->filename);
3729 ret = do_unlinkat(un->dfd, un->filename);
3731 req->flags &= ~REQ_F_NEED_CLEANUP;
3734 io_req_complete(req, ret);
3738 static int io_mkdirat_prep(struct io_kiocb *req,
3739 const struct io_uring_sqe *sqe)
3741 struct io_mkdir *mkd = &req->mkdir;
3742 const char __user *fname;
3744 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3746 if (sqe->ioprio || sqe->off || sqe->rw_flags || sqe->buf_index ||
3749 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3752 mkd->dfd = READ_ONCE(sqe->fd);
3753 mkd->mode = READ_ONCE(sqe->len);
3755 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
3756 mkd->filename = getname(fname);
3757 if (IS_ERR(mkd->filename))
3758 return PTR_ERR(mkd->filename);
3760 req->flags |= REQ_F_NEED_CLEANUP;
3764 static int io_mkdirat(struct io_kiocb *req, int issue_flags)
3766 struct io_mkdir *mkd = &req->mkdir;
3769 if (issue_flags & IO_URING_F_NONBLOCK)
3772 ret = do_mkdirat(mkd->dfd, mkd->filename, mkd->mode);
3774 req->flags &= ~REQ_F_NEED_CLEANUP;
3777 io_req_complete(req, ret);
3781 static int io_symlinkat_prep(struct io_kiocb *req,
3782 const struct io_uring_sqe *sqe)
3784 struct io_symlink *sl = &req->symlink;
3785 const char __user *oldpath, *newpath;
3787 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3789 if (sqe->ioprio || sqe->len || sqe->rw_flags || sqe->buf_index ||
3792 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3795 sl->new_dfd = READ_ONCE(sqe->fd);
3796 oldpath = u64_to_user_ptr(READ_ONCE(sqe->addr));
3797 newpath = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3799 sl->oldpath = getname(oldpath);
3800 if (IS_ERR(sl->oldpath))
3801 return PTR_ERR(sl->oldpath);
3803 sl->newpath = getname(newpath);
3804 if (IS_ERR(sl->newpath)) {
3805 putname(sl->oldpath);
3806 return PTR_ERR(sl->newpath);
3809 req->flags |= REQ_F_NEED_CLEANUP;
3813 static int io_symlinkat(struct io_kiocb *req, int issue_flags)
3815 struct io_symlink *sl = &req->symlink;
3818 if (issue_flags & IO_URING_F_NONBLOCK)
3821 ret = do_symlinkat(sl->oldpath, sl->new_dfd, sl->newpath);
3823 req->flags &= ~REQ_F_NEED_CLEANUP;
3826 io_req_complete(req, ret);
3830 static int io_linkat_prep(struct io_kiocb *req,
3831 const struct io_uring_sqe *sqe)
3833 struct io_hardlink *lnk = &req->hardlink;
3834 const char __user *oldf, *newf;
3836 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3838 if (sqe->ioprio || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
3840 if (unlikely(req->flags & REQ_F_FIXED_FILE))
3843 lnk->old_dfd = READ_ONCE(sqe->fd);
3844 lnk->new_dfd = READ_ONCE(sqe->len);
3845 oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
3846 newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
3847 lnk->flags = READ_ONCE(sqe->hardlink_flags);
3849 lnk->oldpath = getname(oldf);
3850 if (IS_ERR(lnk->oldpath))
3851 return PTR_ERR(lnk->oldpath);
3853 lnk->newpath = getname(newf);
3854 if (IS_ERR(lnk->newpath)) {
3855 putname(lnk->oldpath);
3856 return PTR_ERR(lnk->newpath);
3859 req->flags |= REQ_F_NEED_CLEANUP;
3863 static int io_linkat(struct io_kiocb *req, int issue_flags)
3865 struct io_hardlink *lnk = &req->hardlink;
3868 if (issue_flags & IO_URING_F_NONBLOCK)
3871 ret = do_linkat(lnk->old_dfd, lnk->oldpath, lnk->new_dfd,
3872 lnk->newpath, lnk->flags);
3874 req->flags &= ~REQ_F_NEED_CLEANUP;
3877 io_req_complete(req, ret);
3881 static int io_shutdown_prep(struct io_kiocb *req,
3882 const struct io_uring_sqe *sqe)
3884 #if defined(CONFIG_NET)
3885 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3887 if (unlikely(sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags ||
3888 sqe->buf_index || sqe->splice_fd_in))
3891 req->shutdown.how = READ_ONCE(sqe->len);
3898 static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
3900 #if defined(CONFIG_NET)
3901 struct socket *sock;
3904 if (issue_flags & IO_URING_F_NONBLOCK)
3907 sock = sock_from_file(req->file);
3908 if (unlikely(!sock))
3911 ret = __sys_shutdown_sock(sock, req->shutdown.how);
3914 io_req_complete(req, ret);
3921 static int __io_splice_prep(struct io_kiocb *req,
3922 const struct io_uring_sqe *sqe)
3924 struct io_splice *sp = &req->splice;
3925 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
3927 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
3931 sp->len = READ_ONCE(sqe->len);
3932 sp->flags = READ_ONCE(sqe->splice_flags);
3934 if (unlikely(sp->flags & ~valid_flags))
3937 sp->file_in = io_file_get(req->ctx, req, READ_ONCE(sqe->splice_fd_in),
3938 (sp->flags & SPLICE_F_FD_IN_FIXED));
3941 req->flags |= REQ_F_NEED_CLEANUP;
3945 static int io_tee_prep(struct io_kiocb *req,
3946 const struct io_uring_sqe *sqe)
3948 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
3950 return __io_splice_prep(req, sqe);
3953 static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
3955 struct io_splice *sp = &req->splice;
3956 struct file *in = sp->file_in;
3957 struct file *out = sp->file_out;
3958 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3961 if (issue_flags & IO_URING_F_NONBLOCK)
3964 ret = do_tee(in, out, sp->len, flags);
3966 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
3968 req->flags &= ~REQ_F_NEED_CLEANUP;
3972 io_req_complete(req, ret);
3976 static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3978 struct io_splice *sp = &req->splice;
3980 sp->off_in = READ_ONCE(sqe->splice_off_in);
3981 sp->off_out = READ_ONCE(sqe->off);
3982 return __io_splice_prep(req, sqe);
3985 static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
3987 struct io_splice *sp = &req->splice;
3988 struct file *in = sp->file_in;
3989 struct file *out = sp->file_out;
3990 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
3991 loff_t *poff_in, *poff_out;
3994 if (issue_flags & IO_URING_F_NONBLOCK)
3997 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
3998 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
4001 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
4003 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
4005 req->flags &= ~REQ_F_NEED_CLEANUP;
4009 io_req_complete(req, ret);
4014 * IORING_OP_NOP just posts a completion event, nothing else.
4016 static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
4018 struct io_ring_ctx *ctx = req->ctx;
4020 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
4023 __io_req_complete(req, issue_flags, 0, 0);
4027 static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4029 struct io_ring_ctx *ctx = req->ctx;
4034 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
4036 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
4040 req->sync.flags = READ_ONCE(sqe->fsync_flags);
4041 if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
4044 req->sync.off = READ_ONCE(sqe->off);
4045 req->sync.len = READ_ONCE(sqe->len);
4049 static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
4051 loff_t end = req->sync.off + req->sync.len;
4054 /* fsync always requires a blocking context */
4055 if (issue_flags & IO_URING_F_NONBLOCK)
4058 ret = vfs_fsync_range(req->file, req->sync.off,
4059 end > 0 ? end : LLONG_MAX,
4060 req->sync.flags & IORING_FSYNC_DATASYNC);
4063 io_req_complete(req, ret);
4067 static int io_fallocate_prep(struct io_kiocb *req,
4068 const struct io_uring_sqe *sqe)
4070 if (sqe->ioprio || sqe->buf_index || sqe->rw_flags ||
4073 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4076 req->sync.off = READ_ONCE(sqe->off);
4077 req->sync.len = READ_ONCE(sqe->addr);
4078 req->sync.mode = READ_ONCE(sqe->len);
4082 static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
4086 /* fallocate always requiring blocking context */
4087 if (issue_flags & IO_URING_F_NONBLOCK)
4089 ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
4093 io_req_complete(req, ret);
4097 static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4099 const char __user *fname;
4102 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4104 if (unlikely(sqe->ioprio || sqe->buf_index))
4106 if (unlikely(req->flags & REQ_F_FIXED_FILE))
4109 /* open.how should be already initialised */
4110 if (!(req->open.how.flags & O_PATH) && force_o_largefile())
4111 req->open.how.flags |= O_LARGEFILE;
4113 req->open.dfd = READ_ONCE(sqe->fd);
4114 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
4115 req->open.filename = getname(fname);
4116 if (IS_ERR(req->open.filename)) {
4117 ret = PTR_ERR(req->open.filename);
4118 req->open.filename = NULL;
4122 req->open.file_slot = READ_ONCE(sqe->file_index);
4123 if (req->open.file_slot && (req->open.how.flags & O_CLOEXEC))
4126 req->open.nofile = rlimit(RLIMIT_NOFILE);
4127 req->flags |= REQ_F_NEED_CLEANUP;
4131 static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4133 u64 mode = READ_ONCE(sqe->len);
4134 u64 flags = READ_ONCE(sqe->open_flags);
4136 req->open.how = build_open_how(flags, mode);
4137 return __io_openat_prep(req, sqe);
4140 static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4142 struct open_how __user *how;
4146 how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4147 len = READ_ONCE(sqe->len);
4148 if (len < OPEN_HOW_SIZE_VER0)
4151 ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
4156 return __io_openat_prep(req, sqe);
4159 static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
4161 struct open_flags op;
4163 bool resolve_nonblock, nonblock_set;
4164 bool fixed = !!req->open.file_slot;
4167 ret = build_open_flags(&req->open.how, &op);
4170 nonblock_set = op.open_flag & O_NONBLOCK;
4171 resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
4172 if (issue_flags & IO_URING_F_NONBLOCK) {
4174 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
4175 * it'll always -EAGAIN
4177 if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
4179 op.lookup_flags |= LOOKUP_CACHED;
4180 op.open_flag |= O_NONBLOCK;
4184 ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
4189 file = do_filp_open(req->open.dfd, req->open.filename, &op);
4192 * We could hang on to this 'fd' on retrying, but seems like
4193 * marginal gain for something that is now known to be a slower
4194 * path. So just put it, and we'll get a new one when we retry.
4199 ret = PTR_ERR(file);
4200 /* only retry if RESOLVE_CACHED wasn't already set by application */
4201 if (ret == -EAGAIN &&
4202 (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)))
4207 if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
4208 file->f_flags &= ~O_NONBLOCK;
4209 fsnotify_open(file);
4212 fd_install(ret, file);
4214 ret = io_install_fixed_file(req, file, issue_flags,
4215 req->open.file_slot - 1);
4217 putname(req->open.filename);
4218 req->flags &= ~REQ_F_NEED_CLEANUP;
4221 __io_req_complete(req, issue_flags, ret, 0);
4225 static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
4227 return io_openat2(req, issue_flags);
4230 static int io_remove_buffers_prep(struct io_kiocb *req,
4231 const struct io_uring_sqe *sqe)
4233 struct io_provide_buf *p = &req->pbuf;
4236 if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off ||
4240 tmp = READ_ONCE(sqe->fd);
4241 if (!tmp || tmp > USHRT_MAX)
4244 memset(p, 0, sizeof(*p));
4246 p->bgid = READ_ONCE(sqe->buf_group);
4250 static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
4251 int bgid, unsigned nbufs)
4255 /* shouldn't happen */
4259 /* the head kbuf is the list itself */
4260 while (!list_empty(&buf->list)) {
4261 struct io_buffer *nxt;
4263 nxt = list_first_entry(&buf->list, struct io_buffer, list);
4264 list_del(&nxt->list);
4271 xa_erase(&ctx->io_buffers, bgid);
4276 static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
4278 struct io_provide_buf *p = &req->pbuf;
4279 struct io_ring_ctx *ctx = req->ctx;
4280 struct io_buffer *head;
4282 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4284 io_ring_submit_lock(ctx, !force_nonblock);
4286 lockdep_assert_held(&ctx->uring_lock);
4289 head = xa_load(&ctx->io_buffers, p->bgid);
4291 ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
4295 /* complete before unlock, IOPOLL may need the lock */
4296 __io_req_complete(req, issue_flags, ret, 0);
4297 io_ring_submit_unlock(ctx, !force_nonblock);
4301 static int io_provide_buffers_prep(struct io_kiocb *req,
4302 const struct io_uring_sqe *sqe)
4304 unsigned long size, tmp_check;
4305 struct io_provide_buf *p = &req->pbuf;
4308 if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
4311 tmp = READ_ONCE(sqe->fd);
4312 if (!tmp || tmp > USHRT_MAX)
4315 p->addr = READ_ONCE(sqe->addr);
4316 p->len = READ_ONCE(sqe->len);
4318 if (check_mul_overflow((unsigned long)p->len, (unsigned long)p->nbufs,
4321 if (check_add_overflow((unsigned long)p->addr, size, &tmp_check))
4324 size = (unsigned long)p->len * p->nbufs;
4325 if (!access_ok(u64_to_user_ptr(p->addr), size))
4328 p->bgid = READ_ONCE(sqe->buf_group);
4329 tmp = READ_ONCE(sqe->off);
4330 if (tmp > USHRT_MAX)
4336 static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
4338 struct io_buffer *buf;
4339 u64 addr = pbuf->addr;
4340 int i, bid = pbuf->bid;
4342 for (i = 0; i < pbuf->nbufs; i++) {
4343 buf = kmalloc(sizeof(*buf), GFP_KERNEL);
4348 buf->len = min_t(__u32, pbuf->len, MAX_RW_COUNT);
4353 INIT_LIST_HEAD(&buf->list);
4356 list_add_tail(&buf->list, &(*head)->list);
4360 return i ? i : -ENOMEM;
4363 static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
4365 struct io_provide_buf *p = &req->pbuf;
4366 struct io_ring_ctx *ctx = req->ctx;
4367 struct io_buffer *head, *list;
4369 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4371 io_ring_submit_lock(ctx, !force_nonblock);
4373 lockdep_assert_held(&ctx->uring_lock);
4375 list = head = xa_load(&ctx->io_buffers, p->bgid);
4377 ret = io_add_buffers(p, &head);
4378 if (ret >= 0 && !list) {
4379 ret = xa_insert(&ctx->io_buffers, p->bgid, head, GFP_KERNEL);
4381 __io_remove_buffers(ctx, head, p->bgid, -1U);
4385 /* complete before unlock, IOPOLL may need the lock */
4386 __io_req_complete(req, issue_flags, ret, 0);
4387 io_ring_submit_unlock(ctx, !force_nonblock);
4391 static int io_epoll_ctl_prep(struct io_kiocb *req,
4392 const struct io_uring_sqe *sqe)
4394 #if defined(CONFIG_EPOLL)
4395 if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
4397 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4400 req->epoll.epfd = READ_ONCE(sqe->fd);
4401 req->epoll.op = READ_ONCE(sqe->len);
4402 req->epoll.fd = READ_ONCE(sqe->off);
4404 if (ep_op_has_event(req->epoll.op)) {
4405 struct epoll_event __user *ev;
4407 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
4408 if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
4418 static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
4420 #if defined(CONFIG_EPOLL)
4421 struct io_epoll *ie = &req->epoll;
4423 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4425 ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
4426 if (force_nonblock && ret == -EAGAIN)
4431 __io_req_complete(req, issue_flags, ret, 0);
4438 static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4440 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4441 if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->splice_fd_in)
4443 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4446 req->madvise.addr = READ_ONCE(sqe->addr);
4447 req->madvise.len = READ_ONCE(sqe->len);
4448 req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
4455 static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
4457 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
4458 struct io_madvise *ma = &req->madvise;
4461 if (issue_flags & IO_URING_F_NONBLOCK)
4464 ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
4467 io_req_complete(req, ret);
4474 static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4476 if (sqe->ioprio || sqe->buf_index || sqe->addr || sqe->splice_fd_in)
4478 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4481 req->fadvise.offset = READ_ONCE(sqe->off);
4482 req->fadvise.len = READ_ONCE(sqe->len);
4483 req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
4487 static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
4489 struct io_fadvise *fa = &req->fadvise;
4492 if (issue_flags & IO_URING_F_NONBLOCK) {
4493 switch (fa->advice) {
4494 case POSIX_FADV_NORMAL:
4495 case POSIX_FADV_RANDOM:
4496 case POSIX_FADV_SEQUENTIAL:
4503 ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
4506 __io_req_complete(req, issue_flags, ret, 0);
4510 static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4512 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4514 if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
4516 if (req->flags & REQ_F_FIXED_FILE)
4519 req->statx.dfd = READ_ONCE(sqe->fd);
4520 req->statx.mask = READ_ONCE(sqe->len);
4521 req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
4522 req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4523 req->statx.flags = READ_ONCE(sqe->statx_flags);
4528 static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
4530 struct io_statx *ctx = &req->statx;
4533 if (issue_flags & IO_URING_F_NONBLOCK)
4536 ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
4541 io_req_complete(req, ret);
4545 static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4547 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4549 if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
4550 sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
4552 if (req->flags & REQ_F_FIXED_FILE)
4555 req->close.fd = READ_ONCE(sqe->fd);
4559 static int io_close(struct io_kiocb *req, unsigned int issue_flags)
4561 struct files_struct *files = current->files;
4562 struct io_close *close = &req->close;
4563 struct fdtable *fdt;
4564 struct file *file = NULL;
4567 spin_lock(&files->file_lock);
4568 fdt = files_fdtable(files);
4569 if (close->fd >= fdt->max_fds) {
4570 spin_unlock(&files->file_lock);
4573 file = fdt->fd[close->fd];
4574 if (!file || file->f_op == &io_uring_fops) {
4575 spin_unlock(&files->file_lock);
4580 /* if the file has a flush method, be safe and punt to async */
4581 if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
4582 spin_unlock(&files->file_lock);
4586 ret = __close_fd_get_file(close->fd, &file);
4587 spin_unlock(&files->file_lock);
4594 /* No ->flush() or already async, safely close from here */
4595 ret = filp_close(file, current->files);
4601 __io_req_complete(req, issue_flags, ret, 0);
4605 static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4607 struct io_ring_ctx *ctx = req->ctx;
4609 if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
4611 if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
4615 req->sync.off = READ_ONCE(sqe->off);
4616 req->sync.len = READ_ONCE(sqe->len);
4617 req->sync.flags = READ_ONCE(sqe->sync_range_flags);
4621 static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
4625 /* sync_file_range always requires a blocking context */
4626 if (issue_flags & IO_URING_F_NONBLOCK)
4629 ret = sync_file_range(req->file, req->sync.off, req->sync.len,
4633 io_req_complete(req, ret);
4637 #if defined(CONFIG_NET)
4638 static int io_setup_async_msg(struct io_kiocb *req,
4639 struct io_async_msghdr *kmsg)
4641 struct io_async_msghdr *async_msg = req->async_data;
4645 if (io_alloc_async_data(req)) {
4646 kfree(kmsg->free_iov);
4649 async_msg = req->async_data;
4650 req->flags |= REQ_F_NEED_CLEANUP;
4651 memcpy(async_msg, kmsg, sizeof(*kmsg));
4652 async_msg->msg.msg_name = &async_msg->addr;
4653 /* if were using fast_iov, set it to the new one */
4654 if (!async_msg->free_iov)
4655 async_msg->msg.msg_iter.iov = async_msg->fast_iov;
4660 static int io_sendmsg_copy_hdr(struct io_kiocb *req,
4661 struct io_async_msghdr *iomsg)
4663 iomsg->msg.msg_name = &iomsg->addr;
4664 iomsg->free_iov = iomsg->fast_iov;
4665 return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
4666 req->sr_msg.msg_flags, &iomsg->free_iov);
4669 static int io_sendmsg_prep_async(struct io_kiocb *req)
4673 ret = io_sendmsg_copy_hdr(req, req->async_data);
4675 req->flags |= REQ_F_NEED_CLEANUP;
4679 static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4681 struct io_sr_msg *sr = &req->sr_msg;
4683 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4686 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
4687 sr->len = READ_ONCE(sqe->len);
4688 sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
4689 if (sr->msg_flags & MSG_DONTWAIT)
4690 req->flags |= REQ_F_NOWAIT;
4692 #ifdef CONFIG_COMPAT
4693 if (req->ctx->compat)
4694 sr->msg_flags |= MSG_CMSG_COMPAT;
4699 static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
4701 struct io_async_msghdr iomsg, *kmsg;
4702 struct socket *sock;
4707 sock = sock_from_file(req->file);
4708 if (unlikely(!sock))
4711 kmsg = req->async_data;
4713 ret = io_sendmsg_copy_hdr(req, &iomsg);
4719 flags = req->sr_msg.msg_flags;
4720 if (issue_flags & IO_URING_F_NONBLOCK)
4721 flags |= MSG_DONTWAIT;
4722 if (flags & MSG_WAITALL)
4723 min_ret = iov_iter_count(&kmsg->msg.msg_iter);
4725 ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
4726 if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
4727 return io_setup_async_msg(req, kmsg);
4728 if (ret == -ERESTARTSYS)
4731 /* fast path, check for non-NULL to avoid function call */
4733 kfree(kmsg->free_iov);
4734 req->flags &= ~REQ_F_NEED_CLEANUP;
4737 __io_req_complete(req, issue_flags, ret, 0);
4741 static int io_send(struct io_kiocb *req, unsigned int issue_flags)
4743 struct io_sr_msg *sr = &req->sr_msg;
4746 struct socket *sock;
4751 sock = sock_from_file(req->file);
4752 if (unlikely(!sock))
4755 ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
4759 msg.msg_name = NULL;
4760 msg.msg_control = NULL;
4761 msg.msg_controllen = 0;
4762 msg.msg_namelen = 0;
4764 flags = req->sr_msg.msg_flags;
4765 if (issue_flags & IO_URING_F_NONBLOCK)
4766 flags |= MSG_DONTWAIT;
4767 if (flags & MSG_WAITALL)
4768 min_ret = iov_iter_count(&msg.msg_iter);
4770 msg.msg_flags = flags;
4771 ret = sock_sendmsg(sock, &msg);
4772 if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
4774 if (ret == -ERESTARTSYS)
4779 __io_req_complete(req, issue_flags, ret, 0);
4783 static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
4784 struct io_async_msghdr *iomsg)
4786 struct io_sr_msg *sr = &req->sr_msg;
4787 struct iovec __user *uiov;
4791 ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
4792 &iomsg->uaddr, &uiov, &iov_len);
4796 if (req->flags & REQ_F_BUFFER_SELECT) {
4799 if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
4801 sr->len = iomsg->fast_iov[0].iov_len;
4802 iomsg->free_iov = NULL;
4804 iomsg->free_iov = iomsg->fast_iov;
4805 ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
4806 &iomsg->free_iov, &iomsg->msg.msg_iter,
4815 #ifdef CONFIG_COMPAT
4816 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
4817 struct io_async_msghdr *iomsg)
4819 struct io_sr_msg *sr = &req->sr_msg;
4820 struct compat_iovec __user *uiov;
4825 ret = __get_compat_msghdr(&iomsg->msg, sr->umsg_compat, &iomsg->uaddr,
4830 uiov = compat_ptr(ptr);
4831 if (req->flags & REQ_F_BUFFER_SELECT) {
4832 compat_ssize_t clen;
4836 if (!access_ok(uiov, sizeof(*uiov)))
4838 if (__get_user(clen, &uiov->iov_len))
4843 iomsg->free_iov = NULL;
4845 iomsg->free_iov = iomsg->fast_iov;
4846 ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
4847 UIO_FASTIOV, &iomsg->free_iov,
4848 &iomsg->msg.msg_iter, true);
4857 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
4858 struct io_async_msghdr *iomsg)
4860 iomsg->msg.msg_name = &iomsg->addr;
4862 #ifdef CONFIG_COMPAT
4863 if (req->ctx->compat)
4864 return __io_compat_recvmsg_copy_hdr(req, iomsg);
4867 return __io_recvmsg_copy_hdr(req, iomsg);
4870 static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
4873 struct io_sr_msg *sr = &req->sr_msg;
4874 struct io_buffer *kbuf;
4876 kbuf = io_buffer_select(req, &sr->len, sr->bgid, sr->kbuf, needs_lock);
4881 req->flags |= REQ_F_BUFFER_SELECTED;
4885 static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
4887 return io_put_kbuf(req, req->sr_msg.kbuf);
4890 static int io_recvmsg_prep_async(struct io_kiocb *req)
4894 ret = io_recvmsg_copy_hdr(req, req->async_data);
4896 req->flags |= REQ_F_NEED_CLEANUP;
4900 static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
4902 struct io_sr_msg *sr = &req->sr_msg;
4904 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
4907 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
4908 sr->len = READ_ONCE(sqe->len);
4909 sr->bgid = READ_ONCE(sqe->buf_group);
4910 sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
4911 if (sr->msg_flags & MSG_DONTWAIT)
4912 req->flags |= REQ_F_NOWAIT;
4914 #ifdef CONFIG_COMPAT
4915 if (req->ctx->compat)
4916 sr->msg_flags |= MSG_CMSG_COMPAT;
4921 static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
4923 struct io_async_msghdr iomsg, *kmsg;
4924 struct socket *sock;
4925 struct io_buffer *kbuf;
4928 int ret, cflags = 0;
4929 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4931 sock = sock_from_file(req->file);
4932 if (unlikely(!sock))
4935 kmsg = req->async_data;
4937 ret = io_recvmsg_copy_hdr(req, &iomsg);
4943 if (req->flags & REQ_F_BUFFER_SELECT) {
4944 kbuf = io_recv_buffer_select(req, !force_nonblock);
4946 return PTR_ERR(kbuf);
4947 kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
4948 kmsg->fast_iov[0].iov_len = req->sr_msg.len;
4949 iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov,
4950 1, req->sr_msg.len);
4953 flags = req->sr_msg.msg_flags;
4955 flags |= MSG_DONTWAIT;
4956 if (flags & MSG_WAITALL)
4957 min_ret = iov_iter_count(&kmsg->msg.msg_iter);
4959 ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
4960 kmsg->uaddr, flags);
4961 if (force_nonblock && ret == -EAGAIN)
4962 return io_setup_async_msg(req, kmsg);
4963 if (ret == -ERESTARTSYS)
4966 if (req->flags & REQ_F_BUFFER_SELECTED)
4967 cflags = io_put_recv_kbuf(req);
4968 /* fast path, check for non-NULL to avoid function call */
4970 kfree(kmsg->free_iov);
4971 req->flags &= ~REQ_F_NEED_CLEANUP;
4972 if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
4974 __io_req_complete(req, issue_flags, ret, cflags);
4978 static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
4980 struct io_buffer *kbuf;
4981 struct io_sr_msg *sr = &req->sr_msg;
4983 void __user *buf = sr->buf;
4984 struct socket *sock;
4988 int ret, cflags = 0;
4989 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4991 sock = sock_from_file(req->file);
4992 if (unlikely(!sock))
4995 if (req->flags & REQ_F_BUFFER_SELECT) {
4996 kbuf = io_recv_buffer_select(req, !force_nonblock);
4998 return PTR_ERR(kbuf);
4999 buf = u64_to_user_ptr(kbuf->addr);
5002 ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
5006 msg.msg_name = NULL;
5007 msg.msg_control = NULL;
5008 msg.msg_controllen = 0;
5009 msg.msg_namelen = 0;
5010 msg.msg_iocb = NULL;
5013 flags = req->sr_msg.msg_flags;
5015 flags |= MSG_DONTWAIT;
5016 if (flags & MSG_WAITALL)
5017 min_ret = iov_iter_count(&msg.msg_iter);
5019 ret = sock_recvmsg(sock, &msg, flags);
5020 if (force_nonblock && ret == -EAGAIN)
5022 if (ret == -ERESTARTSYS)
5025 if (req->flags & REQ_F_BUFFER_SELECTED)
5026 cflags = io_put_recv_kbuf(req);
5027 if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
5029 __io_req_complete(req, issue_flags, ret, cflags);
5033 static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5035 struct io_accept *accept = &req->accept;
5037 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5039 if (sqe->ioprio || sqe->len || sqe->buf_index)
5042 accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
5043 accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
5044 accept->flags = READ_ONCE(sqe->accept_flags);
5045 accept->nofile = rlimit(RLIMIT_NOFILE);
5047 accept->file_slot = READ_ONCE(sqe->file_index);
5048 if (accept->file_slot && ((req->open.how.flags & O_CLOEXEC) ||
5049 (accept->flags & SOCK_CLOEXEC)))
5051 if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
5053 if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
5054 accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
5058 static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
5060 struct io_accept *accept = &req->accept;
5061 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
5062 unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
5063 bool fixed = !!accept->file_slot;
5067 if (req->file->f_flags & O_NONBLOCK)
5068 req->flags |= REQ_F_NOWAIT;
5071 fd = __get_unused_fd_flags(accept->flags, accept->nofile);
5072 if (unlikely(fd < 0))
5075 file = do_accept(req->file, file_flags, accept->addr, accept->addr_len,
5080 ret = PTR_ERR(file);
5081 if (ret == -EAGAIN && force_nonblock)
5083 if (ret == -ERESTARTSYS)
5086 } else if (!fixed) {
5087 fd_install(fd, file);
5090 ret = io_install_fixed_file(req, file, issue_flags,
5091 accept->file_slot - 1);
5093 __io_req_complete(req, issue_flags, ret, 0);
5097 static int io_connect_prep_async(struct io_kiocb *req)
5099 struct io_async_connect *io = req->async_data;
5100 struct io_connect *conn = &req->connect;
5102 return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
5105 static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5107 struct io_connect *conn = &req->connect;
5109 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5111 if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags ||
5115 conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
5116 conn->addr_len = READ_ONCE(sqe->addr2);
5120 static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
5122 struct io_async_connect __io, *io;
5123 unsigned file_flags;
5125 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
5127 if (req->async_data) {
5128 io = req->async_data;
5130 ret = move_addr_to_kernel(req->connect.addr,
5131 req->connect.addr_len,
5138 file_flags = force_nonblock ? O_NONBLOCK : 0;
5140 ret = __sys_connect_file(req->file, &io->address,
5141 req->connect.addr_len, file_flags);
5142 if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
5143 if (req->async_data)
5145 if (io_alloc_async_data(req)) {
5149 memcpy(req->async_data, &__io, sizeof(__io));
5152 if (ret == -ERESTARTSYS)
5157 __io_req_complete(req, issue_flags, ret, 0);
5160 #else /* !CONFIG_NET */
5161 #define IO_NETOP_FN(op) \
5162 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
5164 return -EOPNOTSUPP; \
5167 #define IO_NETOP_PREP(op) \
5169 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
5171 return -EOPNOTSUPP; \
5174 #define IO_NETOP_PREP_ASYNC(op) \
5176 static int io_##op##_prep_async(struct io_kiocb *req) \
5178 return -EOPNOTSUPP; \
5181 IO_NETOP_PREP_ASYNC(sendmsg);
5182 IO_NETOP_PREP_ASYNC(recvmsg);
5183 IO_NETOP_PREP_ASYNC(connect);
5184 IO_NETOP_PREP(accept);
5187 #endif /* CONFIG_NET */
5189 struct io_poll_table {
5190 struct poll_table_struct pt;
5191 struct io_kiocb *req;
5196 static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll,
5197 __poll_t mask, io_req_tw_func_t func)
5199 /* for instances that support it check for an event match first: */
5200 if (mask && !(mask & poll->events))
5203 trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
5205 list_del_init(&poll->wait.entry);
5208 req->io_task_work.func = func;
5211 * If this fails, then the task is exiting. When a task exits, the
5212 * work gets canceled, so just cancel this request as well instead
5213 * of executing it. We can't safely execute it anyway, as we may not
5214 * have the needed state needed for it anyway.
5216 io_req_task_work_add(req);
5220 static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
5221 __acquires(&req->ctx->completion_lock)
5223 struct io_ring_ctx *ctx = req->ctx;
5225 /* req->task == current here, checking PF_EXITING is safe */
5226 if (unlikely(req->task->flags & PF_EXITING))
5227 WRITE_ONCE(poll->canceled, true);
5229 if (!req->result && !READ_ONCE(poll->canceled)) {
5230 struct poll_table_struct pt = { ._key = poll->events };
5232 req->result = vfs_poll(req->file, &pt) & poll->events;
5235 spin_lock(&ctx->completion_lock);
5236 if (!req->result && !READ_ONCE(poll->canceled)) {
5237 add_wait_queue(poll->head, &poll->wait);
5244 static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
5246 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
5247 if (req->opcode == IORING_OP_POLL_ADD)
5248 return req->async_data;
5249 return req->apoll->double_poll;
5252 static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
5254 if (req->opcode == IORING_OP_POLL_ADD)
5256 return &req->apoll->poll;
5259 static void io_poll_remove_double(struct io_kiocb *req)
5260 __must_hold(&req->ctx->completion_lock)
5262 struct io_poll_iocb *poll = io_poll_get_double(req);
5264 lockdep_assert_held(&req->ctx->completion_lock);
5266 if (poll && poll->head) {
5267 struct wait_queue_head *head = poll->head;
5269 spin_lock_irq(&head->lock);
5270 list_del_init(&poll->wait.entry);
5271 if (poll->wait.private)
5274 spin_unlock_irq(&head->lock);
5278 static bool __io_poll_complete(struct io_kiocb *req, __poll_t mask)
5279 __must_hold(&req->ctx->completion_lock)
5281 struct io_ring_ctx *ctx = req->ctx;
5282 unsigned flags = IORING_CQE_F_MORE;
5285 if (READ_ONCE(req->poll.canceled)) {
5287 req->poll.events |= EPOLLONESHOT;
5289 error = mangle_poll(mask);
5291 if (req->poll.events & EPOLLONESHOT)
5293 if (!io_cqring_fill_event(ctx, req->user_data, error, flags)) {
5294 req->poll.done = true;
5297 if (flags & IORING_CQE_F_MORE)
5300 return !(flags & IORING_CQE_F_MORE);
5303 static inline bool io_poll_complete(struct io_kiocb *req, __poll_t mask)
5304 __must_hold(&req->ctx->completion_lock)
5308 done = __io_poll_complete(req, mask);
5309 io_commit_cqring(req->ctx);
5313 static void io_poll_task_func(struct io_kiocb *req, bool *locked)
5315 struct io_ring_ctx *ctx = req->ctx;
5316 struct io_kiocb *nxt;
5318 if (io_poll_rewait(req, &req->poll)) {
5319 spin_unlock(&ctx->completion_lock);
5323 done = __io_poll_complete(req, req->result);
5325 io_poll_remove_double(req);
5326 hash_del(&req->hash_node);
5329 add_wait_queue(req->poll.head, &req->poll.wait);
5331 io_commit_cqring(ctx);
5332 spin_unlock(&ctx->completion_lock);
5333 io_cqring_ev_posted(ctx);
5336 nxt = io_put_req_find_next(req);
5338 io_req_task_submit(nxt, locked);
5343 static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode,
5344 int sync, void *key)
5346 struct io_kiocb *req = wait->private;
5347 struct io_poll_iocb *poll = io_poll_get_single(req);
5348 __poll_t mask = key_to_poll(key);
5349 unsigned long flags;
5351 /* for instances that support it check for an event match first: */
5352 if (mask && !(mask & poll->events))
5354 if (!(poll->events & EPOLLONESHOT))
5355 return poll->wait.func(&poll->wait, mode, sync, key);
5357 list_del_init(&wait->entry);
5362 spin_lock_irqsave(&poll->head->lock, flags);
5363 done = list_empty(&poll->wait.entry);
5365 list_del_init(&poll->wait.entry);
5366 /* make sure double remove sees this as being gone */
5367 wait->private = NULL;
5368 spin_unlock_irqrestore(&poll->head->lock, flags);
5370 /* use wait func handler, so it matches the rq type */
5371 poll->wait.func(&poll->wait, mode, sync, key);
5378 static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
5379 wait_queue_func_t wake_func)
5383 poll->canceled = false;
5384 #define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
5385 /* mask in events that we always want/need */
5386 poll->events = events | IO_POLL_UNMASK;
5387 INIT_LIST_HEAD(&poll->wait.entry);
5388 init_waitqueue_func_entry(&poll->wait, wake_func);
5391 static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
5392 struct wait_queue_head *head,
5393 struct io_poll_iocb **poll_ptr)
5395 struct io_kiocb *req = pt->req;
5398 * The file being polled uses multiple waitqueues for poll handling
5399 * (e.g. one for read, one for write). Setup a separate io_poll_iocb
5402 if (unlikely(pt->nr_entries)) {
5403 struct io_poll_iocb *poll_one = poll;
5405 /* double add on the same waitqueue head, ignore */
5406 if (poll_one->head == head)
5408 /* already have a 2nd entry, fail a third attempt */
5410 if ((*poll_ptr)->head == head)
5412 pt->error = -EINVAL;
5416 * Can't handle multishot for double wait for now, turn it
5417 * into one-shot mode.
5419 if (!(poll_one->events & EPOLLONESHOT))
5420 poll_one->events |= EPOLLONESHOT;
5421 poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
5423 pt->error = -ENOMEM;
5426 io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
5428 poll->wait.private = req;
5435 if (poll->events & EPOLLEXCLUSIVE)
5436 add_wait_queue_exclusive(head, &poll->wait);
5438 add_wait_queue(head, &poll->wait);
5441 static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
5442 struct poll_table_struct *p)
5444 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
5445 struct async_poll *apoll = pt->req->apoll;
5447 __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
5450 static void io_async_task_func(struct io_kiocb *req, bool *locked)
5452 struct async_poll *apoll = req->apoll;
5453 struct io_ring_ctx *ctx = req->ctx;
5455 trace_io_uring_task_run(req->ctx, req, req->opcode, req->user_data);
5457 if (io_poll_rewait(req, &apoll->poll)) {
5458 spin_unlock(&ctx->completion_lock);
5462 hash_del(&req->hash_node);
5463 io_poll_remove_double(req);
5464 spin_unlock(&ctx->completion_lock);
5466 if (!READ_ONCE(apoll->poll.canceled))
5467 io_req_task_submit(req, locked);
5469 io_req_complete_failed(req, -ECANCELED);
5472 static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5475 struct io_kiocb *req = wait->private;
5476 struct io_poll_iocb *poll = &req->apoll->poll;
5478 trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data,
5481 return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func);
5484 static void io_poll_req_insert(struct io_kiocb *req)
5486 struct io_ring_ctx *ctx = req->ctx;
5487 struct hlist_head *list;
5489 list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
5490 hlist_add_head(&req->hash_node, list);
5493 static __poll_t __io_arm_poll_handler(struct io_kiocb *req,
5494 struct io_poll_iocb *poll,
5495 struct io_poll_table *ipt, __poll_t mask,
5496 wait_queue_func_t wake_func)
5497 __acquires(&ctx->completion_lock)
5499 struct io_ring_ctx *ctx = req->ctx;
5500 bool cancel = false;
5502 INIT_HLIST_NODE(&req->hash_node);
5503 io_init_poll_iocb(poll, mask, wake_func);
5504 poll->file = req->file;
5505 poll->wait.private = req;
5507 ipt->pt._key = mask;
5510 ipt->nr_entries = 0;
5512 mask = vfs_poll(req->file, &ipt->pt) & poll->events;
5513 if (unlikely(!ipt->nr_entries) && !ipt->error)
5514 ipt->error = -EINVAL;
5516 spin_lock(&ctx->completion_lock);
5517 if (ipt->error || (mask && (poll->events & EPOLLONESHOT)))
5518 io_poll_remove_double(req);
5519 if (likely(poll->head)) {
5520 spin_lock_irq(&poll->head->lock);
5521 if (unlikely(list_empty(&poll->wait.entry))) {
5527 if ((mask && (poll->events & EPOLLONESHOT)) || ipt->error)
5528 list_del_init(&poll->wait.entry);
5530 WRITE_ONCE(poll->canceled, true);
5531 else if (!poll->done) /* actually waiting for an event */
5532 io_poll_req_insert(req);
5533 spin_unlock_irq(&poll->head->lock);
5545 static int io_arm_poll_handler(struct io_kiocb *req)
5547 const struct io_op_def *def = &io_op_defs[req->opcode];
5548 struct io_ring_ctx *ctx = req->ctx;
5549 struct async_poll *apoll;
5550 struct io_poll_table ipt;
5551 __poll_t ret, mask = EPOLLONESHOT | POLLERR | POLLPRI;
5554 if (!req->file || !file_can_poll(req->file))
5555 return IO_APOLL_ABORTED;
5556 if (req->flags & REQ_F_POLLED)
5557 return IO_APOLL_ABORTED;
5558 if (!def->pollin && !def->pollout)
5559 return IO_APOLL_ABORTED;
5563 mask |= POLLIN | POLLRDNORM;
5565 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
5566 if ((req->opcode == IORING_OP_RECVMSG) &&
5567 (req->sr_msg.msg_flags & MSG_ERRQUEUE))
5571 mask |= POLLOUT | POLLWRNORM;
5574 /* if we can't nonblock try, then no point in arming a poll handler */
5575 if (!io_file_supports_nowait(req, rw))
5576 return IO_APOLL_ABORTED;
5578 apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
5579 if (unlikely(!apoll))
5580 return IO_APOLL_ABORTED;
5581 apoll->double_poll = NULL;
5583 req->flags |= REQ_F_POLLED;
5584 ipt.pt._qproc = io_async_queue_proc;
5585 io_req_set_refcount(req);
5587 ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask,
5589 spin_unlock(&ctx->completion_lock);
5590 if (ret || ipt.error)
5591 return ret ? IO_APOLL_READY : IO_APOLL_ABORTED;
5593 trace_io_uring_poll_arm(ctx, req, req->opcode, req->user_data,
5594 mask, apoll->poll.events);
5598 static bool __io_poll_remove_one(struct io_kiocb *req,
5599 struct io_poll_iocb *poll, bool do_cancel)
5600 __must_hold(&req->ctx->completion_lock)
5602 bool do_complete = false;
5606 spin_lock_irq(&poll->head->lock);
5608 WRITE_ONCE(poll->canceled, true);
5609 if (!list_empty(&poll->wait.entry)) {
5610 list_del_init(&poll->wait.entry);
5613 spin_unlock_irq(&poll->head->lock);
5614 hash_del(&req->hash_node);
5618 static bool io_poll_remove_one(struct io_kiocb *req)
5619 __must_hold(&req->ctx->completion_lock)
5623 io_poll_remove_double(req);
5624 do_complete = __io_poll_remove_one(req, io_poll_get_single(req), true);
5627 io_cqring_fill_event(req->ctx, req->user_data, -ECANCELED, 0);
5628 io_commit_cqring(req->ctx);
5630 io_put_req_deferred(req);
5636 * Returns true if we found and killed one or more poll requests
5638 static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk,
5641 struct hlist_node *tmp;
5642 struct io_kiocb *req;
5645 spin_lock(&ctx->completion_lock);
5646 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
5647 struct hlist_head *list;
5649 list = &ctx->cancel_hash[i];
5650 hlist_for_each_entry_safe(req, tmp, list, hash_node) {
5651 if (io_match_task(req, tsk, cancel_all))
5652 posted += io_poll_remove_one(req);
5655 spin_unlock(&ctx->completion_lock);
5658 io_cqring_ev_posted(ctx);
5663 static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, __u64 sqe_addr,
5665 __must_hold(&ctx->completion_lock)
5667 struct hlist_head *list;
5668 struct io_kiocb *req;
5670 list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
5671 hlist_for_each_entry(req, list, hash_node) {
5672 if (sqe_addr != req->user_data)
5674 if (poll_only && req->opcode != IORING_OP_POLL_ADD)
5681 static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr,
5683 __must_hold(&ctx->completion_lock)
5685 struct io_kiocb *req;
5687 req = io_poll_find(ctx, sqe_addr, poll_only);
5690 if (io_poll_remove_one(req))
5696 static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
5701 events = READ_ONCE(sqe->poll32_events);
5703 events = swahw32(events);
5705 if (!(flags & IORING_POLL_ADD_MULTI))
5706 events |= EPOLLONESHOT;
5707 return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
5710 static int io_poll_update_prep(struct io_kiocb *req,
5711 const struct io_uring_sqe *sqe)
5713 struct io_poll_update *upd = &req->poll_update;
5716 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5718 if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
5720 flags = READ_ONCE(sqe->len);
5721 if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA |
5722 IORING_POLL_ADD_MULTI))
5724 /* meaningless without update */
5725 if (flags == IORING_POLL_ADD_MULTI)
5728 upd->old_user_data = READ_ONCE(sqe->addr);
5729 upd->update_events = flags & IORING_POLL_UPDATE_EVENTS;
5730 upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA;
5732 upd->new_user_data = READ_ONCE(sqe->off);
5733 if (!upd->update_user_data && upd->new_user_data)
5735 if (upd->update_events)
5736 upd->events = io_poll_parse_events(sqe, flags);
5737 else if (sqe->poll32_events)
5743 static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
5746 struct io_kiocb *req = wait->private;
5747 struct io_poll_iocb *poll = &req->poll;
5749 return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func);
5752 static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
5753 struct poll_table_struct *p)
5755 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
5757 __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
5760 static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5762 struct io_poll_iocb *poll = &req->poll;
5765 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5767 if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->addr)
5769 flags = READ_ONCE(sqe->len);
5770 if (flags & ~IORING_POLL_ADD_MULTI)
5773 io_req_set_refcount(req);
5774 poll->events = io_poll_parse_events(sqe, flags);
5778 static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
5780 struct io_poll_iocb *poll = &req->poll;
5781 struct io_ring_ctx *ctx = req->ctx;
5782 struct io_poll_table ipt;
5785 ipt.pt._qproc = io_poll_queue_proc;
5787 mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,
5790 if (mask) { /* no async, we'd stolen it */
5792 io_poll_complete(req, mask);
5794 spin_unlock(&ctx->completion_lock);
5797 io_cqring_ev_posted(ctx);
5798 if (poll->events & EPOLLONESHOT)
5804 static int io_poll_update(struct io_kiocb *req, unsigned int issue_flags)
5806 struct io_ring_ctx *ctx = req->ctx;
5807 struct io_kiocb *preq;
5811 spin_lock(&ctx->completion_lock);
5812 preq = io_poll_find(ctx, req->poll_update.old_user_data, true);
5818 if (!req->poll_update.update_events && !req->poll_update.update_user_data) {
5820 ret = io_poll_remove_one(preq) ? 0 : -EALREADY;
5825 * Don't allow racy completion with singleshot, as we cannot safely
5826 * update those. For multishot, if we're racing with completion, just
5827 * let completion re-add it.
5829 completing = !__io_poll_remove_one(preq, &preq->poll, false);
5830 if (completing && (preq->poll.events & EPOLLONESHOT)) {
5834 /* we now have a detached poll request. reissue. */
5838 spin_unlock(&ctx->completion_lock);
5840 io_req_complete(req, ret);
5843 /* only mask one event flags, keep behavior flags */
5844 if (req->poll_update.update_events) {
5845 preq->poll.events &= ~0xffff;
5846 preq->poll.events |= req->poll_update.events & 0xffff;
5847 preq->poll.events |= IO_POLL_UNMASK;
5849 if (req->poll_update.update_user_data)
5850 preq->user_data = req->poll_update.new_user_data;
5851 spin_unlock(&ctx->completion_lock);
5853 /* complete update request, we're done with it */
5854 io_req_complete(req, ret);
5857 ret = io_poll_add(preq, issue_flags);
5860 io_req_complete(preq, ret);
5866 static void io_req_task_timeout(struct io_kiocb *req, bool *locked)
5869 io_req_complete_post(req, -ETIME, 0);
5872 static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
5874 struct io_timeout_data *data = container_of(timer,
5875 struct io_timeout_data, timer);
5876 struct io_kiocb *req = data->req;
5877 struct io_ring_ctx *ctx = req->ctx;
5878 unsigned long flags;
5880 spin_lock_irqsave(&ctx->timeout_lock, flags);
5881 list_del_init(&req->timeout.list);
5882 atomic_set(&req->ctx->cq_timeouts,
5883 atomic_read(&req->ctx->cq_timeouts) + 1);
5884 spin_unlock_irqrestore(&ctx->timeout_lock, flags);
5886 req->io_task_work.func = io_req_task_timeout;
5887 io_req_task_work_add(req);
5888 return HRTIMER_NORESTART;
5891 static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
5893 __must_hold(&ctx->timeout_lock)
5895 struct io_timeout_data *io;
5896 struct io_kiocb *req;
5899 list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
5900 found = user_data == req->user_data;
5905 return ERR_PTR(-ENOENT);
5907 io = req->async_data;
5908 if (hrtimer_try_to_cancel(&io->timer) == -1)
5909 return ERR_PTR(-EALREADY);
5910 list_del_init(&req->timeout.list);
5914 static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
5915 __must_hold(&ctx->completion_lock)
5916 __must_hold(&ctx->timeout_lock)
5918 struct io_kiocb *req = io_timeout_extract(ctx, user_data);
5921 return PTR_ERR(req);
5924 io_cqring_fill_event(ctx, req->user_data, -ECANCELED, 0);
5925 io_put_req_deferred(req);
5929 static clockid_t io_timeout_get_clock(struct io_timeout_data *data)
5931 switch (data->flags & IORING_TIMEOUT_CLOCK_MASK) {
5932 case IORING_TIMEOUT_BOOTTIME:
5933 return CLOCK_BOOTTIME;
5934 case IORING_TIMEOUT_REALTIME:
5935 return CLOCK_REALTIME;
5937 /* can't happen, vetted at prep time */
5941 return CLOCK_MONOTONIC;
5945 static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
5946 struct timespec64 *ts, enum hrtimer_mode mode)
5947 __must_hold(&ctx->timeout_lock)
5949 struct io_timeout_data *io;
5950 struct io_kiocb *req;
5953 list_for_each_entry(req, &ctx->ltimeout_list, timeout.list) {
5954 found = user_data == req->user_data;
5961 io = req->async_data;
5962 if (hrtimer_try_to_cancel(&io->timer) == -1)
5964 hrtimer_init(&io->timer, io_timeout_get_clock(io), mode);
5965 io->timer.function = io_link_timeout_fn;
5966 hrtimer_start(&io->timer, timespec64_to_ktime(*ts), mode);
5970 static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
5971 struct timespec64 *ts, enum hrtimer_mode mode)
5972 __must_hold(&ctx->timeout_lock)
5974 struct io_kiocb *req = io_timeout_extract(ctx, user_data);
5975 struct io_timeout_data *data;
5978 return PTR_ERR(req);
5980 req->timeout.off = 0; /* noseq */
5981 data = req->async_data;
5982 list_add_tail(&req->timeout.list, &ctx->timeout_list);
5983 hrtimer_init(&data->timer, io_timeout_get_clock(data), mode);
5984 data->timer.function = io_timeout_fn;
5985 hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
5989 static int io_timeout_remove_prep(struct io_kiocb *req,
5990 const struct io_uring_sqe *sqe)
5992 struct io_timeout_rem *tr = &req->timeout_rem;
5994 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
5996 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
5998 if (sqe->ioprio || sqe->buf_index || sqe->len || sqe->splice_fd_in)
6001 tr->ltimeout = false;
6002 tr->addr = READ_ONCE(sqe->addr);
6003 tr->flags = READ_ONCE(sqe->timeout_flags);
6004 if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) {
6005 if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
6007 if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
6008 tr->ltimeout = true;
6009 if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK|IORING_TIMEOUT_ABS))
6011 if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
6013 } else if (tr->flags) {
6014 /* timeout removal doesn't support flags */
6021 static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
6023 return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
6028 * Remove or update an existing timeout command
6030 static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
6032 struct io_timeout_rem *tr = &req->timeout_rem;
6033 struct io_ring_ctx *ctx = req->ctx;
6036 if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE)) {
6037 spin_lock(&ctx->completion_lock);
6038 spin_lock_irq(&ctx->timeout_lock);
6039 ret = io_timeout_cancel(ctx, tr->addr);
6040 spin_unlock_irq(&ctx->timeout_lock);
6041 spin_unlock(&ctx->completion_lock);
6043 enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags);
6045 spin_lock_irq(&ctx->timeout_lock);
6047 ret = io_linked_timeout_update(ctx, tr->addr, &tr->ts, mode);
6049 ret = io_timeout_update(ctx, tr->addr, &tr->ts, mode);
6050 spin_unlock_irq(&ctx->timeout_lock);
6055 io_req_complete_post(req, ret, 0);
6059 static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
6060 bool is_timeout_link)
6062 struct io_timeout_data *data;
6064 u32 off = READ_ONCE(sqe->off);
6066 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
6068 if (sqe->ioprio || sqe->buf_index || sqe->len != 1 ||
6071 if (off && is_timeout_link)
6073 flags = READ_ONCE(sqe->timeout_flags);
6074 if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK))
6076 /* more than one clock specified is invalid, obviously */
6077 if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
6080 INIT_LIST_HEAD(&req->timeout.list);
6081 req->timeout.off = off;
6082 if (unlikely(off && !req->ctx->off_timeout_used))
6083 req->ctx->off_timeout_used = true;
6085 if (!req->async_data && io_alloc_async_data(req))
6088 data = req->async_data;
6090 data->flags = flags;
6092 if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
6095 data->mode = io_translate_timeout_mode(flags);
6096 hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode);
6098 if (is_timeout_link) {
6099 struct io_submit_link *link = &req->ctx->submit_state.link;
6103 if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
6105 req->timeout.head = link->last;
6106 link->last->flags |= REQ_F_ARM_LTIMEOUT;
6111 static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
6113 struct io_ring_ctx *ctx = req->ctx;
6114 struct io_timeout_data *data = req->async_data;
6115 struct list_head *entry;
6116 u32 tail, off = req->timeout.off;
6118 spin_lock_irq(&ctx->timeout_lock);
6121 * sqe->off holds how many events that need to occur for this
6122 * timeout event to be satisfied. If it isn't set, then this is
6123 * a pure timeout request, sequence isn't used.
6125 if (io_is_timeout_noseq(req)) {
6126 entry = ctx->timeout_list.prev;
6130 tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
6131 req->timeout.target_seq = tail + off;
6133 /* Update the last seq here in case io_flush_timeouts() hasn't.
6134 * This is safe because ->completion_lock is held, and submissions
6135 * and completions are never mixed in the same ->completion_lock section.
6137 ctx->cq_last_tm_flush = tail;
6140 * Insertion sort, ensuring the first entry in the list is always
6141 * the one we need first.
6143 list_for_each_prev(entry, &ctx->timeout_list) {
6144 struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
6147 if (io_is_timeout_noseq(nxt))
6149 /* nxt.seq is behind @tail, otherwise would've been completed */
6150 if (off >= nxt->timeout.target_seq - tail)
6154 list_add(&req->timeout.list, entry);
6155 data->timer.function = io_timeout_fn;
6156 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
6157 spin_unlock_irq(&ctx->timeout_lock);
6161 struct io_cancel_data {
6162 struct io_ring_ctx *ctx;
6166 static bool io_cancel_cb(struct io_wq_work *work, void *data)
6168 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
6169 struct io_cancel_data *cd = data;
6171 return req->ctx == cd->ctx && req->user_data == cd->user_data;
6174 static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
6175 struct io_ring_ctx *ctx)
6177 struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, };
6178 enum io_wq_cancel cancel_ret;
6181 if (!tctx || !tctx->io_wq)
6184 cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false);
6185 switch (cancel_ret) {
6186 case IO_WQ_CANCEL_OK:
6189 case IO_WQ_CANCEL_RUNNING:
6192 case IO_WQ_CANCEL_NOTFOUND:
6200 static int io_try_cancel_userdata(struct io_kiocb *req, u64 sqe_addr)
6202 struct io_ring_ctx *ctx = req->ctx;
6205 WARN_ON_ONCE(!io_wq_current_is_worker() && req->task != current);
6207 ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
6211 spin_lock(&ctx->completion_lock);
6212 spin_lock_irq(&ctx->timeout_lock);
6213 ret = io_timeout_cancel(ctx, sqe_addr);
6214 spin_unlock_irq(&ctx->timeout_lock);
6217 ret = io_poll_cancel(ctx, sqe_addr, false);
6219 spin_unlock(&ctx->completion_lock);
6223 static int io_async_cancel_prep(struct io_kiocb *req,
6224 const struct io_uring_sqe *sqe)
6226 if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
6228 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
6230 if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags ||
6234 req->cancel.addr = READ_ONCE(sqe->addr);
6238 static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
6240 struct io_ring_ctx *ctx = req->ctx;
6241 u64 sqe_addr = req->cancel.addr;
6242 struct io_tctx_node *node;
6245 ret = io_try_cancel_userdata(req, sqe_addr);
6249 /* slow path, try all io-wq's */
6250 io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
6252 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
6253 struct io_uring_task *tctx = node->task->io_uring;
6255 ret = io_async_cancel_one(tctx, req->cancel.addr, ctx);
6259 io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));
6263 io_req_complete_post(req, ret, 0);
6267 static int io_rsrc_update_prep(struct io_kiocb *req,
6268 const struct io_uring_sqe *sqe)
6270 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
6272 if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
6275 req->rsrc_update.offset = READ_ONCE(sqe->off);
6276 req->rsrc_update.nr_args = READ_ONCE(sqe->len);
6277 if (!req->rsrc_update.nr_args)
6279 req->rsrc_update.arg = READ_ONCE(sqe->addr);
6283 static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
6285 struct io_ring_ctx *ctx = req->ctx;
6286 struct io_uring_rsrc_update2 up;
6289 if (issue_flags & IO_URING_F_NONBLOCK)
6292 up.offset = req->rsrc_update.offset;
6293 up.data = req->rsrc_update.arg;
6298 mutex_lock(&ctx->uring_lock);
6299 ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
6300 &up, req->rsrc_update.nr_args);
6301 mutex_unlock(&ctx->uring_lock);
6305 __io_req_complete(req, issue_flags, ret, 0);
6309 static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
6311 switch (req->opcode) {
6314 case IORING_OP_READV:
6315 case IORING_OP_READ_FIXED:
6316 case IORING_OP_READ:
6317 return io_read_prep(req, sqe);
6318 case IORING_OP_WRITEV:
6319 case IORING_OP_WRITE_FIXED:
6320 case IORING_OP_WRITE:
6321 return io_write_prep(req, sqe);
6322 case IORING_OP_POLL_ADD:
6323 return io_poll_add_prep(req, sqe);
6324 case IORING_OP_POLL_REMOVE:
6325 return io_poll_update_prep(req, sqe);
6326 case IORING_OP_FSYNC:
6327 return io_fsync_prep(req, sqe);
6328 case IORING_OP_SYNC_FILE_RANGE:
6329 return io_sfr_prep(req, sqe);
6330 case IORING_OP_SENDMSG:
6331 case IORING_OP_SEND:
6332 return io_sendmsg_prep(req, sqe);
6333 case IORING_OP_RECVMSG:
6334 case IORING_OP_RECV:
6335 return io_recvmsg_prep(req, sqe);
6336 case IORING_OP_CONNECT:
6337 return io_connect_prep(req, sqe);
6338 case IORING_OP_TIMEOUT:
6339 return io_timeout_prep(req, sqe, false);
6340 case IORING_OP_TIMEOUT_REMOVE:
6341 return io_timeout_remove_prep(req, sqe);
6342 case IORING_OP_ASYNC_CANCEL:
6343 return io_async_cancel_prep(req, sqe);
6344 case IORING_OP_LINK_TIMEOUT:
6345 return io_timeout_prep(req, sqe, true);
6346 case IORING_OP_ACCEPT:
6347 return io_accept_prep(req, sqe);
6348 case IORING_OP_FALLOCATE:
6349 return io_fallocate_prep(req, sqe);
6350 case IORING_OP_OPENAT:
6351 return io_openat_prep(req, sqe);
6352 case IORING_OP_CLOSE:
6353 return io_close_prep(req, sqe);
6354 case IORING_OP_FILES_UPDATE:
6355 return io_rsrc_update_prep(req, sqe);
6356 case IORING_OP_STATX:
6357 return io_statx_prep(req, sqe);
6358 case IORING_OP_FADVISE:
6359 return io_fadvise_prep(req, sqe);
6360 case IORING_OP_MADVISE:
6361 return io_madvise_prep(req, sqe);
6362 case IORING_OP_OPENAT2:
6363 return io_openat2_prep(req, sqe);
6364 case IORING_OP_EPOLL_CTL:
6365 return io_epoll_ctl_prep(req, sqe);
6366 case IORING_OP_SPLICE:
6367 return io_splice_prep(req, sqe);
6368 case IORING_OP_PROVIDE_BUFFERS:
6369 return io_provide_buffers_prep(req, sqe);
6370 case IORING_OP_REMOVE_BUFFERS:
6371 return io_remove_buffers_prep(req, sqe);
6373 return io_tee_prep(req, sqe);
6374 case IORING_OP_SHUTDOWN:
6375 return io_shutdown_prep(req, sqe);
6376 case IORING_OP_RENAMEAT:
6377 return io_renameat_prep(req, sqe);
6378 case IORING_OP_UNLINKAT:
6379 return io_unlinkat_prep(req, sqe);
6380 case IORING_OP_MKDIRAT:
6381 return io_mkdirat_prep(req, sqe);
6382 case IORING_OP_SYMLINKAT:
6383 return io_symlinkat_prep(req, sqe);
6384 case IORING_OP_LINKAT:
6385 return io_linkat_prep(req, sqe);
6388 printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
6393 static int io_req_prep_async(struct io_kiocb *req)
6395 if (!io_op_defs[req->opcode].needs_async_setup)
6397 if (WARN_ON_ONCE(req->async_data))
6399 if (io_alloc_async_data(req))
6402 switch (req->opcode) {
6403 case IORING_OP_READV:
6404 return io_rw_prep_async(req, READ);
6405 case IORING_OP_WRITEV:
6406 return io_rw_prep_async(req, WRITE);
6407 case IORING_OP_SENDMSG:
6408 return io_sendmsg_prep_async(req);
6409 case IORING_OP_RECVMSG:
6410 return io_recvmsg_prep_async(req);
6411 case IORING_OP_CONNECT:
6412 return io_connect_prep_async(req);
6414 printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n",
6419 static u32 io_get_sequence(struct io_kiocb *req)
6421 u32 seq = req->ctx->cached_sq_head;
6423 /* need original cached_sq_head, but it was increased for each req */
6424 io_for_each_link(req, req)
6429 static bool io_drain_req(struct io_kiocb *req)
6431 struct io_kiocb *pos;
6432 struct io_ring_ctx *ctx = req->ctx;
6433 struct io_defer_entry *de;
6437 if (req->flags & REQ_F_FAIL) {
6438 io_req_complete_fail_submit(req);
6443 * If we need to drain a request in the middle of a link, drain the
6444 * head request and the next request/link after the current link.
6445 * Considering sequential execution of links, IOSQE_IO_DRAIN will be
6446 * maintained for every request of our link.
6448 if (ctx->drain_next) {
6449 req->flags |= REQ_F_IO_DRAIN;
6450 ctx->drain_next = false;
6452 /* not interested in head, start from the first linked */
6453 io_for_each_link(pos, req->link) {
6454 if (pos->flags & REQ_F_IO_DRAIN) {
6455 ctx->drain_next = true;
6456 req->flags |= REQ_F_IO_DRAIN;
6461 /* Still need defer if there is pending req in defer list. */
6462 if (likely(list_empty_careful(&ctx->defer_list) &&
6463 !(req->flags & REQ_F_IO_DRAIN))) {
6464 ctx->drain_active = false;
6468 seq = io_get_sequence(req);
6469 /* Still a chance to pass the sequence check */
6470 if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list))
6473 ret = io_req_prep_async(req);
6476 io_prep_async_link(req);
6477 de = kmalloc(sizeof(*de), GFP_KERNEL);
6481 io_req_complete_failed(req, ret);
6485 spin_lock(&ctx->completion_lock);
6486 if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
6487 spin_unlock(&ctx->completion_lock);
6489 io_queue_async_work(req, NULL);
6493 trace_io_uring_defer(ctx, req, req->user_data);
6496 list_add_tail(&de->list, &ctx->defer_list);
6497 spin_unlock(&ctx->completion_lock);
6501 static void io_clean_op(struct io_kiocb *req)
6503 if (req->flags & REQ_F_BUFFER_SELECTED) {
6504 switch (req->opcode) {
6505 case IORING_OP_READV:
6506 case IORING_OP_READ_FIXED:
6507 case IORING_OP_READ:
6508 kfree((void *)(unsigned long)req->rw.addr);
6510 case IORING_OP_RECVMSG:
6511 case IORING_OP_RECV:
6512 kfree(req->sr_msg.kbuf);
6517 if (req->flags & REQ_F_NEED_CLEANUP) {
6518 switch (req->opcode) {
6519 case IORING_OP_READV:
6520 case IORING_OP_READ_FIXED:
6521 case IORING_OP_READ:
6522 case IORING_OP_WRITEV:
6523 case IORING_OP_WRITE_FIXED:
6524 case IORING_OP_WRITE: {
6525 struct io_async_rw *io = req->async_data;
6527 kfree(io->free_iovec);
6530 case IORING_OP_RECVMSG:
6531 case IORING_OP_SENDMSG: {
6532 struct io_async_msghdr *io = req->async_data;
6534 kfree(io->free_iov);
6537 case IORING_OP_SPLICE:
6539 if (!(req->splice.flags & SPLICE_F_FD_IN_FIXED))
6540 io_put_file(req->splice.file_in);
6542 case IORING_OP_OPENAT:
6543 case IORING_OP_OPENAT2:
6544 if (req->open.filename)
6545 putname(req->open.filename);
6547 case IORING_OP_RENAMEAT:
6548 putname(req->rename.oldpath);
6549 putname(req->rename.newpath);
6551 case IORING_OP_UNLINKAT:
6552 putname(req->unlink.filename);
6554 case IORING_OP_MKDIRAT:
6555 putname(req->mkdir.filename);
6557 case IORING_OP_SYMLINKAT:
6558 putname(req->symlink.oldpath);
6559 putname(req->symlink.newpath);
6561 case IORING_OP_LINKAT:
6562 putname(req->hardlink.oldpath);
6563 putname(req->hardlink.newpath);
6567 if ((req->flags & REQ_F_POLLED) && req->apoll) {
6568 kfree(req->apoll->double_poll);
6572 if (req->flags & REQ_F_INFLIGHT) {
6573 struct io_uring_task *tctx = req->task->io_uring;
6575 atomic_dec(&tctx->inflight_tracked);
6577 if (req->flags & REQ_F_CREDS)
6578 put_cred(req->creds);
6580 req->flags &= ~IO_REQ_CLEAN_FLAGS;
6583 static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
6585 struct io_ring_ctx *ctx = req->ctx;
6586 const struct cred *creds = NULL;
6589 if ((req->flags & REQ_F_CREDS) && req->creds != current_cred())
6590 creds = override_creds(req->creds);
6592 switch (req->opcode) {
6594 ret = io_nop(req, issue_flags);
6596 case IORING_OP_READV:
6597 case IORING_OP_READ_FIXED:
6598 case IORING_OP_READ:
6599 ret = io_read(req, issue_flags);
6601 case IORING_OP_WRITEV:
6602 case IORING_OP_WRITE_FIXED:
6603 case IORING_OP_WRITE:
6604 ret = io_write(req, issue_flags);
6606 case IORING_OP_FSYNC:
6607 ret = io_fsync(req, issue_flags);
6609 case IORING_OP_POLL_ADD:
6610 ret = io_poll_add(req, issue_flags);
6612 case IORING_OP_POLL_REMOVE:
6613 ret = io_poll_update(req, issue_flags);
6615 case IORING_OP_SYNC_FILE_RANGE:
6616 ret = io_sync_file_range(req, issue_flags);
6618 case IORING_OP_SENDMSG:
6619 ret = io_sendmsg(req, issue_flags);
6621 case IORING_OP_SEND:
6622 ret = io_send(req, issue_flags);
6624 case IORING_OP_RECVMSG:
6625 ret = io_recvmsg(req, issue_flags);
6627 case IORING_OP_RECV:
6628 ret = io_recv(req, issue_flags);
6630 case IORING_OP_TIMEOUT:
6631 ret = io_timeout(req, issue_flags);
6633 case IORING_OP_TIMEOUT_REMOVE:
6634 ret = io_timeout_remove(req, issue_flags);
6636 case IORING_OP_ACCEPT:
6637 ret = io_accept(req, issue_flags);
6639 case IORING_OP_CONNECT:
6640 ret = io_connect(req, issue_flags);
6642 case IORING_OP_ASYNC_CANCEL:
6643 ret = io_async_cancel(req, issue_flags);
6645 case IORING_OP_FALLOCATE:
6646 ret = io_fallocate(req, issue_flags);
6648 case IORING_OP_OPENAT:
6649 ret = io_openat(req, issue_flags);
6651 case IORING_OP_CLOSE:
6652 ret = io_close(req, issue_flags);
6654 case IORING_OP_FILES_UPDATE:
6655 ret = io_files_update(req, issue_flags);
6657 case IORING_OP_STATX:
6658 ret = io_statx(req, issue_flags);
6660 case IORING_OP_FADVISE:
6661 ret = io_fadvise(req, issue_flags);
6663 case IORING_OP_MADVISE:
6664 ret = io_madvise(req, issue_flags);
6666 case IORING_OP_OPENAT2:
6667 ret = io_openat2(req, issue_flags);
6669 case IORING_OP_EPOLL_CTL:
6670 ret = io_epoll_ctl(req, issue_flags);
6672 case IORING_OP_SPLICE:
6673 ret = io_splice(req, issue_flags);
6675 case IORING_OP_PROVIDE_BUFFERS:
6676 ret = io_provide_buffers(req, issue_flags);
6678 case IORING_OP_REMOVE_BUFFERS:
6679 ret = io_remove_buffers(req, issue_flags);
6682 ret = io_tee(req, issue_flags);
6684 case IORING_OP_SHUTDOWN:
6685 ret = io_shutdown(req, issue_flags);
6687 case IORING_OP_RENAMEAT:
6688 ret = io_renameat(req, issue_flags);
6690 case IORING_OP_UNLINKAT:
6691 ret = io_unlinkat(req, issue_flags);
6693 case IORING_OP_MKDIRAT:
6694 ret = io_mkdirat(req, issue_flags);
6696 case IORING_OP_SYMLINKAT:
6697 ret = io_symlinkat(req, issue_flags);
6699 case IORING_OP_LINKAT:
6700 ret = io_linkat(req, issue_flags);
6708 revert_creds(creds);
6711 /* If the op doesn't have a file, we're not polling for it */
6712 if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file)
6713 io_iopoll_req_issued(req);
6718 static struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
6720 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
6722 req = io_put_req_find_next(req);
6723 return req ? &req->work : NULL;
6726 static void io_wq_submit_work(struct io_wq_work *work)
6728 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
6729 struct io_kiocb *timeout;
6732 /* one will be dropped by ->io_free_work() after returning to io-wq */
6733 if (!(req->flags & REQ_F_REFCOUNT))
6734 __io_req_set_refcount(req, 2);
6738 timeout = io_prep_linked_timeout(req);
6740 io_queue_linked_timeout(timeout);
6742 /* either cancelled or io-wq is dying, so don't touch tctx->iowq */
6743 if (work->flags & IO_WQ_WORK_CANCEL)
6748 ret = io_issue_sqe(req, 0);
6750 * We can get EAGAIN for polled IO even though we're
6751 * forcing a sync submission from here, since we can't
6752 * wait for request slots on the block side.
6760 /* avoid locking problems by failing it from a clean context */
6762 io_req_task_queue_fail(req, ret);
6765 static inline struct io_fixed_file *io_fixed_file_slot(struct io_file_table *table,
6768 return &table->files[i];
6771 static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
6774 struct io_fixed_file *slot = io_fixed_file_slot(&ctx->file_table, index);
6776 return (struct file *) (slot->file_ptr & FFS_MASK);
6779 static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file)
6781 unsigned long file_ptr = (unsigned long) file;
6783 if (__io_file_supports_nowait(file, READ))
6784 file_ptr |= FFS_ASYNC_READ;
6785 if (__io_file_supports_nowait(file, WRITE))
6786 file_ptr |= FFS_ASYNC_WRITE;
6787 if (S_ISREG(file_inode(file)->i_mode))
6788 file_ptr |= FFS_ISREG;
6789 file_slot->file_ptr = file_ptr;
6792 static inline struct file *io_file_get_fixed(struct io_ring_ctx *ctx,
6793 struct io_kiocb *req, int fd)
6796 unsigned long file_ptr;
6798 if (unlikely((unsigned int)fd >= ctx->nr_user_files))
6800 fd = array_index_nospec(fd, ctx->nr_user_files);
6801 file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr;
6802 file = (struct file *) (file_ptr & FFS_MASK);
6803 file_ptr &= ~FFS_MASK;
6804 /* mask in overlapping REQ_F and FFS bits */
6805 req->flags |= (file_ptr << REQ_F_NOWAIT_READ_BIT);
6806 io_req_set_rsrc_node(req);
6810 static struct file *io_file_get_normal(struct io_ring_ctx *ctx,
6811 struct io_kiocb *req, int fd)
6813 struct file *file = fget(fd);
6815 trace_io_uring_file_get(ctx, fd);
6817 /* we don't allow fixed io_uring files */
6818 if (file && unlikely(file->f_op == &io_uring_fops))
6819 io_req_track_inflight(req);
6823 static inline struct file *io_file_get(struct io_ring_ctx *ctx,
6824 struct io_kiocb *req, int fd, bool fixed)
6827 return io_file_get_fixed(ctx, req, fd);
6829 return io_file_get_normal(ctx, req, fd);
6832 static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked)
6834 struct io_kiocb *prev = req->timeout.prev;
6838 ret = io_try_cancel_userdata(req, prev->user_data);
6839 io_req_complete_post(req, ret ?: -ETIME, 0);
6842 io_req_complete_post(req, -ETIME, 0);
6846 static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
6848 struct io_timeout_data *data = container_of(timer,
6849 struct io_timeout_data, timer);
6850 struct io_kiocb *prev, *req = data->req;
6851 struct io_ring_ctx *ctx = req->ctx;
6852 unsigned long flags;
6854 spin_lock_irqsave(&ctx->timeout_lock, flags);
6855 prev = req->timeout.head;
6856 req->timeout.head = NULL;
6859 * We don't expect the list to be empty, that will only happen if we
6860 * race with the completion of the linked work.
6863 io_remove_next_linked(prev);
6864 if (!req_ref_inc_not_zero(prev))
6867 list_del(&req->timeout.list);
6868 req->timeout.prev = prev;
6869 spin_unlock_irqrestore(&ctx->timeout_lock, flags);
6871 req->io_task_work.func = io_req_task_link_timeout;
6872 io_req_task_work_add(req);
6873 return HRTIMER_NORESTART;
6876 static void io_queue_linked_timeout(struct io_kiocb *req)
6878 struct io_ring_ctx *ctx = req->ctx;
6880 spin_lock_irq(&ctx->timeout_lock);
6882 * If the back reference is NULL, then our linked request finished
6883 * before we got a chance to setup the timer
6885 if (req->timeout.head) {
6886 struct io_timeout_data *data = req->async_data;
6888 data->timer.function = io_link_timeout_fn;
6889 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
6891 list_add_tail(&req->timeout.list, &ctx->ltimeout_list);
6893 spin_unlock_irq(&ctx->timeout_lock);
6894 /* drop submission reference */
6898 static void __io_queue_sqe(struct io_kiocb *req)
6899 __must_hold(&req->ctx->uring_lock)
6901 struct io_kiocb *linked_timeout;
6905 ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
6908 * We async punt it if the file wasn't marked NOWAIT, or if the file
6909 * doesn't support non-blocking read/write attempts
6912 if (req->flags & REQ_F_COMPLETE_INLINE) {
6913 struct io_ring_ctx *ctx = req->ctx;
6914 struct io_submit_state *state = &ctx->submit_state;
6916 state->compl_reqs[state->compl_nr++] = req;
6917 if (state->compl_nr == ARRAY_SIZE(state->compl_reqs))
6918 io_submit_flush_completions(ctx);
6922 linked_timeout = io_prep_linked_timeout(req);
6924 io_queue_linked_timeout(linked_timeout);
6925 } else if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
6926 linked_timeout = io_prep_linked_timeout(req);
6928 switch (io_arm_poll_handler(req)) {
6929 case IO_APOLL_READY:
6931 io_unprep_linked_timeout(req);
6933 case IO_APOLL_ABORTED:
6935 * Queued up for async execution, worker will release
6936 * submit reference when the iocb is actually submitted.
6938 io_queue_async_work(req, NULL);
6943 io_queue_linked_timeout(linked_timeout);
6945 io_req_complete_failed(req, ret);
6949 static inline void io_queue_sqe(struct io_kiocb *req)
6950 __must_hold(&req->ctx->uring_lock)
6952 if (unlikely(req->ctx->drain_active) && io_drain_req(req))
6955 if (likely(!(req->flags & (REQ_F_FORCE_ASYNC | REQ_F_FAIL)))) {
6956 __io_queue_sqe(req);
6957 } else if (req->flags & REQ_F_FAIL) {
6958 io_req_complete_fail_submit(req);
6960 int ret = io_req_prep_async(req);
6963 io_req_complete_failed(req, ret);
6965 io_queue_async_work(req, NULL);
6970 * Check SQE restrictions (opcode and flags).
6972 * Returns 'true' if SQE is allowed, 'false' otherwise.
6974 static inline bool io_check_restriction(struct io_ring_ctx *ctx,
6975 struct io_kiocb *req,
6976 unsigned int sqe_flags)
6978 if (likely(!ctx->restricted))
6981 if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
6984 if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
6985 ctx->restrictions.sqe_flags_required)
6988 if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
6989 ctx->restrictions.sqe_flags_required))
6995 static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
6996 const struct io_uring_sqe *sqe)
6997 __must_hold(&ctx->uring_lock)
6999 struct io_submit_state *state;
7000 unsigned int sqe_flags;
7001 int personality, ret = 0;
7003 /* req is partially pre-initialised, see io_preinit_req() */
7004 req->opcode = READ_ONCE(sqe->opcode);
7005 /* same numerical values with corresponding REQ_F_*, safe to copy */
7006 req->flags = sqe_flags = READ_ONCE(sqe->flags);
7007 req->user_data = READ_ONCE(sqe->user_data);
7009 req->fixed_rsrc_refs = NULL;
7010 req->task = current;
7012 /* enforce forwards compatibility on users */
7013 if (unlikely(sqe_flags & ~SQE_VALID_FLAGS))
7015 if (unlikely(req->opcode >= IORING_OP_LAST))
7017 if (!io_check_restriction(ctx, req, sqe_flags))
7020 if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
7021 !io_op_defs[req->opcode].buffer_select)
7023 if (unlikely(sqe_flags & IOSQE_IO_DRAIN))
7024 ctx->drain_active = true;
7026 personality = READ_ONCE(sqe->personality);
7028 req->creds = xa_load(&ctx->personalities, personality);
7031 get_cred(req->creds);
7032 req->flags |= REQ_F_CREDS;
7034 state = &ctx->submit_state;
7037 * Plug now if we have more than 1 IO left after this, and the target
7038 * is potentially a read/write to block based storage.
7040 if (!state->plug_started && state->ios_left > 1 &&
7041 io_op_defs[req->opcode].plug) {
7042 blk_start_plug(&state->plug);
7043 state->plug_started = true;
7046 if (io_op_defs[req->opcode].needs_file) {
7047 req->file = io_file_get(ctx, req, READ_ONCE(sqe->fd),
7048 (sqe_flags & IOSQE_FIXED_FILE));
7049 if (unlikely(!req->file))
7057 static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
7058 const struct io_uring_sqe *sqe)
7059 __must_hold(&ctx->uring_lock)
7061 struct io_submit_link *link = &ctx->submit_state.link;
7064 ret = io_init_req(ctx, req, sqe);
7065 if (unlikely(ret)) {
7067 /* fail even hard links since we don't submit */
7070 * we can judge a link req is failed or cancelled by if
7071 * REQ_F_FAIL is set, but the head is an exception since
7072 * it may be set REQ_F_FAIL because of other req's failure
7073 * so let's leverage req->result to distinguish if a head
7074 * is set REQ_F_FAIL because of its failure or other req's
7075 * failure so that we can set the correct ret code for it.
7076 * init result here to avoid affecting the normal path.
7078 if (!(link->head->flags & REQ_F_FAIL))
7079 req_fail_link_node(link->head, -ECANCELED);
7080 } else if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
7082 * the current req is a normal req, we should return
7083 * error and thus break the submittion loop.
7085 io_req_complete_failed(req, ret);
7088 req_fail_link_node(req, ret);
7090 ret = io_req_prep(req, sqe);
7095 /* don't need @sqe from now on */
7096 trace_io_uring_submit_sqe(ctx, req, req->opcode, req->user_data,
7098 ctx->flags & IORING_SETUP_SQPOLL);
7101 * If we already have a head request, queue this one for async
7102 * submittal once the head completes. If we don't have a head but
7103 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
7104 * submitted sync once the chain is complete. If none of those
7105 * conditions are true (normal request), then just queue it.
7108 struct io_kiocb *head = link->head;
7110 if (!(req->flags & REQ_F_FAIL)) {
7111 ret = io_req_prep_async(req);
7112 if (unlikely(ret)) {
7113 req_fail_link_node(req, ret);
7114 if (!(head->flags & REQ_F_FAIL))
7115 req_fail_link_node(head, -ECANCELED);
7118 trace_io_uring_link(ctx, req, head);
7119 link->last->link = req;
7122 /* last request of a link, enqueue the link */
7123 if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
7128 if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
7140 * Batched submission is done, ensure local IO is flushed out.
7142 static void io_submit_state_end(struct io_submit_state *state,
7143 struct io_ring_ctx *ctx)
7145 if (state->link.head)
7146 io_queue_sqe(state->link.head);
7147 if (state->compl_nr)
7148 io_submit_flush_completions(ctx);
7149 if (state->plug_started)
7150 blk_finish_plug(&state->plug);
7154 * Start submission side cache.
7156 static void io_submit_state_start(struct io_submit_state *state,
7157 unsigned int max_ios)
7159 state->plug_started = false;
7160 state->ios_left = max_ios;
7161 /* set only head, no need to init link_last in advance */
7162 state->link.head = NULL;
7165 static void io_commit_sqring(struct io_ring_ctx *ctx)
7167 struct io_rings *rings = ctx->rings;
7170 * Ensure any loads from the SQEs are done at this point,
7171 * since once we write the new head, the application could
7172 * write new data to them.
7174 smp_store_release(&rings->sq.head, ctx->cached_sq_head);
7178 * Fetch an sqe, if one is available. Note this returns a pointer to memory
7179 * that is mapped by userspace. This means that care needs to be taken to
7180 * ensure that reads are stable, as we cannot rely on userspace always
7181 * being a good citizen. If members of the sqe are validated and then later
7182 * used, it's important that those reads are done through READ_ONCE() to
7183 * prevent a re-load down the line.
7185 static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
7187 unsigned head, mask = ctx->sq_entries - 1;
7188 unsigned sq_idx = ctx->cached_sq_head++ & mask;
7191 * The cached sq head (or cq tail) serves two purposes:
7193 * 1) allows us to batch the cost of updating the user visible
7195 * 2) allows the kernel side to track the head on its own, even
7196 * though the application is the one updating it.
7198 head = READ_ONCE(ctx->sq_array[sq_idx]);
7199 if (likely(head < ctx->sq_entries))
7200 return &ctx->sq_sqes[head];
7202 /* drop invalid entries */
7204 WRITE_ONCE(ctx->rings->sq_dropped,
7205 READ_ONCE(ctx->rings->sq_dropped) + 1);
7209 static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
7210 __must_hold(&ctx->uring_lock)
7214 /* make sure SQ entry isn't read before tail */
7215 nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx));
7216 if (!percpu_ref_tryget_many(&ctx->refs, nr))
7218 io_get_task_refs(nr);
7220 io_submit_state_start(&ctx->submit_state, nr);
7221 while (submitted < nr) {
7222 const struct io_uring_sqe *sqe;
7223 struct io_kiocb *req;
7225 req = io_alloc_req(ctx);
7226 if (unlikely(!req)) {
7228 submitted = -EAGAIN;
7231 sqe = io_get_sqe(ctx);
7232 if (unlikely(!sqe)) {
7233 list_add(&req->inflight_entry, &ctx->submit_state.free_list);
7236 /* will complete beyond this point, count as submitted */
7238 if (io_submit_sqe(ctx, req, sqe))
7242 if (unlikely(submitted != nr)) {
7243 int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
7244 int unused = nr - ref_used;
7246 current->io_uring->cached_refs += unused;
7247 percpu_ref_put_many(&ctx->refs, unused);
7250 io_submit_state_end(&ctx->submit_state, ctx);
7251 /* Commit SQ ring head once we've consumed and submitted all SQEs */
7252 io_commit_sqring(ctx);
7257 static inline bool io_sqd_events_pending(struct io_sq_data *sqd)
7259 return READ_ONCE(sqd->state);
7262 static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
7264 /* Tell userspace we may need a wakeup call */
7265 spin_lock(&ctx->completion_lock);
7266 WRITE_ONCE(ctx->rings->sq_flags,
7267 ctx->rings->sq_flags | IORING_SQ_NEED_WAKEUP);
7268 spin_unlock(&ctx->completion_lock);
7271 static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
7273 spin_lock(&ctx->completion_lock);
7274 WRITE_ONCE(ctx->rings->sq_flags,
7275 ctx->rings->sq_flags & ~IORING_SQ_NEED_WAKEUP);
7276 spin_unlock(&ctx->completion_lock);
7279 static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
7281 unsigned int to_submit;
7284 to_submit = io_sqring_entries(ctx);
7285 /* if we're handling multiple rings, cap submit size for fairness */
7286 if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE)
7287 to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;
7289 if (!list_empty(&ctx->iopoll_list) || to_submit) {
7290 unsigned nr_events = 0;
7291 const struct cred *creds = NULL;
7293 if (ctx->sq_creds != current_cred())
7294 creds = override_creds(ctx->sq_creds);
7296 mutex_lock(&ctx->uring_lock);
7297 if (!list_empty(&ctx->iopoll_list))
7298 io_do_iopoll(ctx, &nr_events, 0);
7301 * Don't submit if refs are dying, good for io_uring_register(),
7302 * but also it is relied upon by io_ring_exit_work()
7304 if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
7305 !(ctx->flags & IORING_SETUP_R_DISABLED))
7306 ret = io_submit_sqes(ctx, to_submit);
7307 mutex_unlock(&ctx->uring_lock);
7309 if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
7310 wake_up(&ctx->sqo_sq_wait);
7312 revert_creds(creds);
7318 static void io_sqd_update_thread_idle(struct io_sq_data *sqd)
7320 struct io_ring_ctx *ctx;
7321 unsigned sq_thread_idle = 0;
7323 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
7324 sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle);
7325 sqd->sq_thread_idle = sq_thread_idle;
7328 static bool io_sqd_handle_event(struct io_sq_data *sqd)
7330 bool did_sig = false;
7331 struct ksignal ksig;
7333 if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
7334 signal_pending(current)) {
7335 mutex_unlock(&sqd->lock);
7336 if (signal_pending(current))
7337 did_sig = get_signal(&ksig);
7339 mutex_lock(&sqd->lock);
7341 return did_sig || test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
7344 static int io_sq_thread(void *data)
7346 struct io_sq_data *sqd = data;
7347 struct io_ring_ctx *ctx;
7348 unsigned long timeout = 0;
7349 char buf[TASK_COMM_LEN];
7352 snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
7353 set_task_comm(current, buf);
7355 if (sqd->sq_cpu != -1)
7356 set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
7358 set_cpus_allowed_ptr(current, cpu_online_mask);
7359 current->flags |= PF_NO_SETAFFINITY;
7361 mutex_lock(&sqd->lock);
7363 bool cap_entries, sqt_spin = false;
7365 if (io_sqd_events_pending(sqd) || signal_pending(current)) {
7366 if (io_sqd_handle_event(sqd))
7368 timeout = jiffies + sqd->sq_thread_idle;
7371 cap_entries = !list_is_singular(&sqd->ctx_list);
7372 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
7373 int ret = __io_sq_thread(ctx, cap_entries);
7375 if (!sqt_spin && (ret > 0 || !list_empty(&ctx->iopoll_list)))
7378 if (io_run_task_work())
7381 if (sqt_spin || !time_after(jiffies, timeout)) {
7384 timeout = jiffies + sqd->sq_thread_idle;
7388 prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
7389 if (!io_sqd_events_pending(sqd) && !current->task_works) {
7390 bool needs_sched = true;
7392 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
7393 io_ring_set_wakeup_flag(ctx);
7395 if ((ctx->flags & IORING_SETUP_IOPOLL) &&
7396 !list_empty_careful(&ctx->iopoll_list)) {
7397 needs_sched = false;
7400 if (io_sqring_entries(ctx)) {
7401 needs_sched = false;
7407 mutex_unlock(&sqd->lock);
7409 mutex_lock(&sqd->lock);
7411 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
7412 io_ring_clear_wakeup_flag(ctx);
7415 finish_wait(&sqd->wait, &wait);
7416 timeout = jiffies + sqd->sq_thread_idle;
7419 io_uring_cancel_generic(true, sqd);
7421 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
7422 io_ring_set_wakeup_flag(ctx);
7424 mutex_unlock(&sqd->lock);
7426 complete(&sqd->exited);
7430 struct io_wait_queue {
7431 struct wait_queue_entry wq;
7432 struct io_ring_ctx *ctx;
7434 unsigned nr_timeouts;
7437 static inline bool io_should_wake(struct io_wait_queue *iowq)
7439 struct io_ring_ctx *ctx = iowq->ctx;
7440 int dist = ctx->cached_cq_tail - (int) iowq->cq_tail;
7443 * Wake up if we have enough events, or if a timeout occurred since we
7444 * started waiting. For timeouts, we always want to return to userspace,
7445 * regardless of event count.
7447 return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
7450 static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
7451 int wake_flags, void *key)
7453 struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
7457 * Cannot safely flush overflowed CQEs from here, ensure we wake up
7458 * the task, and the next invocation will do it.
7460 if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->check_cq_overflow))
7461 return autoremove_wake_function(curr, mode, wake_flags, key);
7465 static int io_run_task_work_sig(void)
7467 if (io_run_task_work())
7469 if (!signal_pending(current))
7471 if (test_thread_flag(TIF_NOTIFY_SIGNAL))
7472 return -ERESTARTSYS;
7476 /* when returns >0, the caller should retry */
7477 static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
7478 struct io_wait_queue *iowq,
7479 signed long *timeout)
7483 /* make sure we run task_work before checking for signals */
7484 ret = io_run_task_work_sig();
7485 if (ret || io_should_wake(iowq))
7487 /* let the caller flush overflows, retry */
7488 if (test_bit(0, &ctx->check_cq_overflow))
7491 *timeout = schedule_timeout(*timeout);
7492 return !*timeout ? -ETIME : 1;
7496 * Wait until events become available, if we don't already have some. The
7497 * application must reap them itself, as they reside on the shared cq ring.
7499 static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
7500 const sigset_t __user *sig, size_t sigsz,
7501 struct __kernel_timespec __user *uts)
7503 struct io_wait_queue iowq;
7504 struct io_rings *rings = ctx->rings;
7505 signed long timeout = MAX_SCHEDULE_TIMEOUT;
7509 io_cqring_overflow_flush(ctx);
7510 if (io_cqring_events(ctx) >= min_events)
7512 if (!io_run_task_work())
7517 #ifdef CONFIG_COMPAT
7518 if (in_compat_syscall())
7519 ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
7523 ret = set_user_sigmask(sig, sigsz);
7530 struct timespec64 ts;
7532 if (get_timespec64(&ts, uts))
7534 timeout = timespec64_to_jiffies(&ts);
7537 init_waitqueue_func_entry(&iowq.wq, io_wake_function);
7538 iowq.wq.private = current;
7539 INIT_LIST_HEAD(&iowq.wq.entry);
7541 iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
7542 iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events;
7544 trace_io_uring_cqring_wait(ctx, min_events);
7546 /* if we can't even flush overflow, don't wait for more */
7547 if (!io_cqring_overflow_flush(ctx)) {
7551 prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq,
7552 TASK_INTERRUPTIBLE);
7553 ret = io_cqring_wait_schedule(ctx, &iowq, &timeout);
7554 finish_wait(&ctx->cq_wait, &iowq.wq);
7558 restore_saved_sigmask_unless(ret == -EINTR);
7560 return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
7563 static void io_free_page_table(void **table, size_t size)
7565 unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
7567 for (i = 0; i < nr_tables; i++)
7572 static void **io_alloc_page_table(size_t size)
7574 unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
7575 size_t init_size = size;
7578 table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT);
7582 for (i = 0; i < nr_tables; i++) {
7583 unsigned int this_size = min_t(size_t, size, PAGE_SIZE);
7585 table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT);
7587 io_free_page_table(table, init_size);
7595 static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node)
7597 percpu_ref_exit(&ref_node->refs);
7601 static void io_rsrc_node_ref_zero(struct percpu_ref *ref)
7603 struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs);
7604 struct io_ring_ctx *ctx = node->rsrc_data->ctx;
7605 unsigned long flags;
7606 bool first_add = false;
7608 spin_lock_irqsave(&ctx->rsrc_ref_lock, flags);
7611 while (!list_empty(&ctx->rsrc_ref_list)) {
7612 node = list_first_entry(&ctx->rsrc_ref_list,
7613 struct io_rsrc_node, node);
7614 /* recycle ref nodes in order */
7617 list_del(&node->node);
7618 first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist);
7620 spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags);
7623 mod_delayed_work(system_wq, &ctx->rsrc_put_work, HZ);
7626 static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx)
7628 struct io_rsrc_node *ref_node;
7630 ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
7634 if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
7639 INIT_LIST_HEAD(&ref_node->node);
7640 INIT_LIST_HEAD(&ref_node->rsrc_list);
7641 ref_node->done = false;
7645 static void io_rsrc_node_switch(struct io_ring_ctx *ctx,
7646 struct io_rsrc_data *data_to_kill)
7648 WARN_ON_ONCE(!ctx->rsrc_backup_node);
7649 WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node);
7652 struct io_rsrc_node *rsrc_node = ctx->rsrc_node;
7654 rsrc_node->rsrc_data = data_to_kill;
7655 spin_lock_irq(&ctx->rsrc_ref_lock);
7656 list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list);
7657 spin_unlock_irq(&ctx->rsrc_ref_lock);
7659 atomic_inc(&data_to_kill->refs);
7660 percpu_ref_kill(&rsrc_node->refs);
7661 ctx->rsrc_node = NULL;
7664 if (!ctx->rsrc_node) {
7665 ctx->rsrc_node = ctx->rsrc_backup_node;
7666 ctx->rsrc_backup_node = NULL;
7670 static int io_rsrc_node_switch_start(struct io_ring_ctx *ctx)
7672 if (ctx->rsrc_backup_node)
7674 ctx->rsrc_backup_node = io_rsrc_node_alloc(ctx);
7675 return ctx->rsrc_backup_node ? 0 : -ENOMEM;
7678 static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, struct io_ring_ctx *ctx)
7682 /* As we may drop ->uring_lock, other task may have started quiesce */
7686 data->quiesce = true;
7688 ret = io_rsrc_node_switch_start(ctx);
7691 io_rsrc_node_switch(ctx, data);
7693 /* kill initial ref, already quiesced if zero */
7694 if (atomic_dec_and_test(&data->refs))
7696 mutex_unlock(&ctx->uring_lock);
7697 flush_delayed_work(&ctx->rsrc_put_work);
7698 ret = wait_for_completion_interruptible(&data->done);
7700 mutex_lock(&ctx->uring_lock);
7704 atomic_inc(&data->refs);
7705 /* wait for all works potentially completing data->done */
7706 flush_delayed_work(&ctx->rsrc_put_work);
7707 reinit_completion(&data->done);
7709 ret = io_run_task_work_sig();
7710 mutex_lock(&ctx->uring_lock);
7712 data->quiesce = false;
7717 static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
7719 unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
7720 unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
7722 return &data->tags[table_idx][off];
7725 static void io_rsrc_data_free(struct io_rsrc_data *data)
7727 size_t size = data->nr * sizeof(data->tags[0][0]);
7730 io_free_page_table((void **)data->tags, size);
7734 static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put,
7735 u64 __user *utags, unsigned nr,
7736 struct io_rsrc_data **pdata)
7738 struct io_rsrc_data *data;
7742 data = kzalloc(sizeof(*data), GFP_KERNEL);
7745 data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0]));
7753 data->do_put = do_put;
7756 for (i = 0; i < nr; i++) {
7757 u64 *tag_slot = io_get_tag_slot(data, i);
7759 if (copy_from_user(tag_slot, &utags[i],
7765 atomic_set(&data->refs, 1);
7766 init_completion(&data->done);
7770 io_rsrc_data_free(data);
7774 static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
7776 table->files = kvcalloc(nr_files, sizeof(table->files[0]),
7777 GFP_KERNEL_ACCOUNT);
7778 return !!table->files;
7781 static void io_free_file_tables(struct io_file_table *table)
7783 kvfree(table->files);
7784 table->files = NULL;
7787 static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
7789 #if defined(CONFIG_UNIX)
7790 if (ctx->ring_sock) {
7791 struct sock *sock = ctx->ring_sock->sk;
7792 struct sk_buff *skb;
7794 while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
7800 for (i = 0; i < ctx->nr_user_files; i++) {
7803 file = io_file_from_index(ctx, i);
7808 io_free_file_tables(&ctx->file_table);
7809 io_rsrc_data_free(ctx->file_data);
7810 ctx->file_data = NULL;
7811 ctx->nr_user_files = 0;
7814 static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
7818 if (!ctx->file_data)
7820 ret = io_rsrc_ref_quiesce(ctx->file_data, ctx);
7822 __io_sqe_files_unregister(ctx);
7826 static void io_sq_thread_unpark(struct io_sq_data *sqd)
7827 __releases(&sqd->lock)
7829 WARN_ON_ONCE(sqd->thread == current);
7832 * Do the dance but not conditional clear_bit() because it'd race with
7833 * other threads incrementing park_pending and setting the bit.
7835 clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7836 if (atomic_dec_return(&sqd->park_pending))
7837 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7838 mutex_unlock(&sqd->lock);
7841 static void io_sq_thread_park(struct io_sq_data *sqd)
7842 __acquires(&sqd->lock)
7844 WARN_ON_ONCE(sqd->thread == current);
7846 atomic_inc(&sqd->park_pending);
7847 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
7848 mutex_lock(&sqd->lock);
7850 wake_up_process(sqd->thread);
7853 static void io_sq_thread_stop(struct io_sq_data *sqd)
7855 WARN_ON_ONCE(sqd->thread == current);
7856 WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state));
7858 set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
7859 mutex_lock(&sqd->lock);
7861 wake_up_process(sqd->thread);
7862 mutex_unlock(&sqd->lock);
7863 wait_for_completion(&sqd->exited);
7866 static void io_put_sq_data(struct io_sq_data *sqd)
7868 if (refcount_dec_and_test(&sqd->refs)) {
7869 WARN_ON_ONCE(atomic_read(&sqd->park_pending));
7871 io_sq_thread_stop(sqd);
7876 static void io_sq_thread_finish(struct io_ring_ctx *ctx)
7878 struct io_sq_data *sqd = ctx->sq_data;
7881 io_sq_thread_park(sqd);
7882 list_del_init(&ctx->sqd_list);
7883 io_sqd_update_thread_idle(sqd);
7884 io_sq_thread_unpark(sqd);
7886 io_put_sq_data(sqd);
7887 ctx->sq_data = NULL;
7891 static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
7893 struct io_ring_ctx *ctx_attach;
7894 struct io_sq_data *sqd;
7897 f = fdget(p->wq_fd);
7899 return ERR_PTR(-ENXIO);
7900 if (f.file->f_op != &io_uring_fops) {
7902 return ERR_PTR(-EINVAL);
7905 ctx_attach = f.file->private_data;
7906 sqd = ctx_attach->sq_data;
7909 return ERR_PTR(-EINVAL);
7911 if (sqd->task_tgid != current->tgid) {
7913 return ERR_PTR(-EPERM);
7916 refcount_inc(&sqd->refs);
7921 static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
7924 struct io_sq_data *sqd;
7927 if (p->flags & IORING_SETUP_ATTACH_WQ) {
7928 sqd = io_attach_sq_data(p);
7933 /* fall through for EPERM case, setup new sqd/task */
7934 if (PTR_ERR(sqd) != -EPERM)
7938 sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
7940 return ERR_PTR(-ENOMEM);
7942 atomic_set(&sqd->park_pending, 0);
7943 refcount_set(&sqd->refs, 1);
7944 INIT_LIST_HEAD(&sqd->ctx_list);
7945 mutex_init(&sqd->lock);
7946 init_waitqueue_head(&sqd->wait);
7947 init_completion(&sqd->exited);
7951 #if defined(CONFIG_UNIX)
7953 * Ensure the UNIX gc is aware of our file set, so we are certain that
7954 * the io_uring can be safely unregistered on process exit, even if we have
7955 * loops in the file referencing.
7957 static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
7959 struct sock *sk = ctx->ring_sock->sk;
7960 struct scm_fp_list *fpl;
7961 struct sk_buff *skb;
7964 fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
7968 skb = alloc_skb(0, GFP_KERNEL);
7977 fpl->user = get_uid(current_user());
7978 for (i = 0; i < nr; i++) {
7979 struct file *file = io_file_from_index(ctx, i + offset);
7983 fpl->fp[nr_files] = get_file(file);
7984 unix_inflight(fpl->user, fpl->fp[nr_files]);
7989 fpl->max = SCM_MAX_FD;
7990 fpl->count = nr_files;
7991 UNIXCB(skb).fp = fpl;
7992 skb->destructor = unix_destruct_scm;
7993 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
7994 skb_queue_head(&sk->sk_receive_queue, skb);
7996 for (i = 0; i < nr_files; i++)
8007 * If UNIX sockets are enabled, fd passing can cause a reference cycle which
8008 * causes regular reference counting to break down. We rely on the UNIX
8009 * garbage collection to take care of this problem for us.
8011 static int io_sqe_files_scm(struct io_ring_ctx *ctx)
8013 unsigned left, total;
8017 left = ctx->nr_user_files;
8019 unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
8021 ret = __io_sqe_files_scm(ctx, this_files, total);
8025 total += this_files;
8031 while (total < ctx->nr_user_files) {
8032 struct file *file = io_file_from_index(ctx, total);
8042 static int io_sqe_files_scm(struct io_ring_ctx *ctx)
8048 static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
8050 struct file *file = prsrc->file;
8051 #if defined(CONFIG_UNIX)
8052 struct sock *sock = ctx->ring_sock->sk;
8053 struct sk_buff_head list, *head = &sock->sk_receive_queue;
8054 struct sk_buff *skb;
8057 __skb_queue_head_init(&list);
8060 * Find the skb that holds this file in its SCM_RIGHTS. When found,
8061 * remove this entry and rearrange the file array.
8063 skb = skb_dequeue(head);
8065 struct scm_fp_list *fp;
8067 fp = UNIXCB(skb).fp;
8068 for (i = 0; i < fp->count; i++) {
8071 if (fp->fp[i] != file)
8074 unix_notinflight(fp->user, fp->fp[i]);
8075 left = fp->count - 1 - i;
8077 memmove(&fp->fp[i], &fp->fp[i + 1],
8078 left * sizeof(struct file *));
8085 __skb_queue_tail(&list, skb);
8095 __skb_queue_tail(&list, skb);
8097 skb = skb_dequeue(head);
8100 if (skb_peek(&list)) {
8101 spin_lock_irq(&head->lock);
8102 while ((skb = __skb_dequeue(&list)) != NULL)
8103 __skb_queue_tail(head, skb);
8104 spin_unlock_irq(&head->lock);
8111 static void __io_rsrc_put_work(struct io_rsrc_node *ref_node)
8113 struct io_rsrc_data *rsrc_data = ref_node->rsrc_data;
8114 struct io_ring_ctx *ctx = rsrc_data->ctx;
8115 struct io_rsrc_put *prsrc, *tmp;
8117 list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
8118 list_del(&prsrc->list);
8121 bool lock_ring = ctx->flags & IORING_SETUP_IOPOLL;
8123 io_ring_submit_lock(ctx, lock_ring);
8124 spin_lock(&ctx->completion_lock);
8125 io_cqring_fill_event(ctx, prsrc->tag, 0, 0);
8127 io_commit_cqring(ctx);
8128 spin_unlock(&ctx->completion_lock);
8129 io_cqring_ev_posted(ctx);
8130 io_ring_submit_unlock(ctx, lock_ring);
8133 rsrc_data->do_put(ctx, prsrc);
8137 io_rsrc_node_destroy(ref_node);
8138 if (atomic_dec_and_test(&rsrc_data->refs))
8139 complete(&rsrc_data->done);
8142 static void io_rsrc_put_work(struct work_struct *work)
8144 struct io_ring_ctx *ctx;
8145 struct llist_node *node;
8147 ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
8148 node = llist_del_all(&ctx->rsrc_put_llist);
8151 struct io_rsrc_node *ref_node;
8152 struct llist_node *next = node->next;
8154 ref_node = llist_entry(node, struct io_rsrc_node, llist);
8155 __io_rsrc_put_work(ref_node);
8160 static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
8161 unsigned nr_args, u64 __user *tags)
8163 __s32 __user *fds = (__s32 __user *) arg;
8172 if (nr_args > IORING_MAX_FIXED_FILES)
8174 if (nr_args > rlimit(RLIMIT_NOFILE))
8176 ret = io_rsrc_node_switch_start(ctx);
8179 ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args,
8185 if (!io_alloc_file_tables(&ctx->file_table, nr_args))
8188 for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
8189 if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
8193 /* allow sparse sets */
8196 if (unlikely(*io_get_tag_slot(ctx->file_data, i)))
8203 if (unlikely(!file))
8207 * Don't allow io_uring instances to be registered. If UNIX
8208 * isn't enabled, then this causes a reference cycle and this
8209 * instance can never get freed. If UNIX is enabled we'll
8210 * handle it just fine, but there's still no point in allowing
8211 * a ring fd as it doesn't support regular read/write anyway.
8213 if (file->f_op == &io_uring_fops) {
8217 io_fixed_file_set(io_fixed_file_slot(&ctx->file_table, i), file);
8220 ret = io_sqe_files_scm(ctx);
8222 __io_sqe_files_unregister(ctx);
8226 io_rsrc_node_switch(ctx, NULL);
8229 for (i = 0; i < ctx->nr_user_files; i++) {
8230 file = io_file_from_index(ctx, i);
8234 io_free_file_tables(&ctx->file_table);
8235 ctx->nr_user_files = 0;
8237 io_rsrc_data_free(ctx->file_data);
8238 ctx->file_data = NULL;
8242 static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
8245 #if defined(CONFIG_UNIX)
8246 struct sock *sock = ctx->ring_sock->sk;
8247 struct sk_buff_head *head = &sock->sk_receive_queue;
8248 struct sk_buff *skb;
8251 * See if we can merge this file into an existing skb SCM_RIGHTS
8252 * file set. If there's no room, fall back to allocating a new skb
8253 * and filling it in.
8255 spin_lock_irq(&head->lock);
8256 skb = skb_peek(head);
8258 struct scm_fp_list *fpl = UNIXCB(skb).fp;
8260 if (fpl->count < SCM_MAX_FD) {
8261 __skb_unlink(skb, head);
8262 spin_unlock_irq(&head->lock);
8263 fpl->fp[fpl->count] = get_file(file);
8264 unix_inflight(fpl->user, fpl->fp[fpl->count]);
8266 spin_lock_irq(&head->lock);
8267 __skb_queue_head(head, skb);
8272 spin_unlock_irq(&head->lock);
8279 return __io_sqe_files_scm(ctx, 1, index);
8285 static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
8286 unsigned int issue_flags, u32 slot_index)
8288 struct io_ring_ctx *ctx = req->ctx;
8289 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
8290 struct io_fixed_file *file_slot;
8293 io_ring_submit_lock(ctx, !force_nonblock);
8294 if (file->f_op == &io_uring_fops)
8297 if (!ctx->file_data)
8300 if (slot_index >= ctx->nr_user_files)
8303 slot_index = array_index_nospec(slot_index, ctx->nr_user_files);
8304 file_slot = io_fixed_file_slot(&ctx->file_table, slot_index);
8306 if (file_slot->file_ptr)
8309 *io_get_tag_slot(ctx->file_data, slot_index) = 0;
8310 io_fixed_file_set(file_slot, file);
8311 ret = io_sqe_file_register(ctx, file, slot_index);
8313 file_slot->file_ptr = 0;
8319 io_ring_submit_unlock(ctx, !force_nonblock);
8325 static int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
8326 struct io_rsrc_node *node, void *rsrc)
8328 struct io_rsrc_put *prsrc;
8330 prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
8334 prsrc->tag = *io_get_tag_slot(data, idx);
8336 list_add(&prsrc->list, &node->rsrc_list);
8340 static int __io_sqe_files_update(struct io_ring_ctx *ctx,
8341 struct io_uring_rsrc_update2 *up,
8344 u64 __user *tags = u64_to_user_ptr(up->tags);
8345 __s32 __user *fds = u64_to_user_ptr(up->data);
8346 struct io_rsrc_data *data = ctx->file_data;
8347 struct io_fixed_file *file_slot;
8351 bool needs_switch = false;
8353 if (!ctx->file_data)
8355 if (up->offset + nr_args > ctx->nr_user_files)
8358 for (done = 0; done < nr_args; done++) {
8361 if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) ||
8362 copy_from_user(&fd, &fds[done], sizeof(fd))) {
8366 if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) {
8370 if (fd == IORING_REGISTER_FILES_SKIP)
8373 i = array_index_nospec(up->offset + done, ctx->nr_user_files);
8374 file_slot = io_fixed_file_slot(&ctx->file_table, i);
8376 if (file_slot->file_ptr) {
8377 file = (struct file *)(file_slot->file_ptr & FFS_MASK);
8378 err = io_queue_rsrc_removal(data, up->offset + done,
8379 ctx->rsrc_node, file);
8382 file_slot->file_ptr = 0;
8383 needs_switch = true;
8392 * Don't allow io_uring instances to be registered. If
8393 * UNIX isn't enabled, then this causes a reference
8394 * cycle and this instance can never get freed. If UNIX
8395 * is enabled we'll handle it just fine, but there's
8396 * still no point in allowing a ring fd as it doesn't
8397 * support regular read/write anyway.
8399 if (file->f_op == &io_uring_fops) {
8404 *io_get_tag_slot(data, up->offset + done) = tag;
8405 io_fixed_file_set(file_slot, file);
8406 err = io_sqe_file_register(ctx, file, i);
8408 file_slot->file_ptr = 0;
8416 io_rsrc_node_switch(ctx, data);
8417 return done ? done : err;
8420 static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
8421 struct task_struct *task)
8423 struct io_wq_hash *hash;
8424 struct io_wq_data data;
8425 unsigned int concurrency;
8427 mutex_lock(&ctx->uring_lock);
8428 hash = ctx->hash_map;
8430 hash = kzalloc(sizeof(*hash), GFP_KERNEL);
8432 mutex_unlock(&ctx->uring_lock);
8433 return ERR_PTR(-ENOMEM);
8435 refcount_set(&hash->refs, 1);
8436 init_waitqueue_head(&hash->wait);
8437 ctx->hash_map = hash;
8439 mutex_unlock(&ctx->uring_lock);
8443 data.free_work = io_wq_free_work;
8444 data.do_work = io_wq_submit_work;
8446 /* Do QD, or 4 * CPUS, whatever is smallest */
8447 concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
8449 return io_wq_create(concurrency, &data);
8452 static int io_uring_alloc_task_context(struct task_struct *task,
8453 struct io_ring_ctx *ctx)
8455 struct io_uring_task *tctx;
8458 tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
8459 if (unlikely(!tctx))
8462 ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
8463 if (unlikely(ret)) {
8468 tctx->io_wq = io_init_wq_offload(ctx, task);
8469 if (IS_ERR(tctx->io_wq)) {
8470 ret = PTR_ERR(tctx->io_wq);
8471 percpu_counter_destroy(&tctx->inflight);
8477 init_waitqueue_head(&tctx->wait);
8478 atomic_set(&tctx->in_idle, 0);
8479 atomic_set(&tctx->inflight_tracked, 0);
8480 task->io_uring = tctx;
8481 spin_lock_init(&tctx->task_lock);
8482 INIT_WQ_LIST(&tctx->task_list);
8483 init_task_work(&tctx->task_work, tctx_task_work);
8487 void __io_uring_free(struct task_struct *tsk)
8489 struct io_uring_task *tctx = tsk->io_uring;
8491 WARN_ON_ONCE(!xa_empty(&tctx->xa));
8492 WARN_ON_ONCE(tctx->io_wq);
8493 WARN_ON_ONCE(tctx->cached_refs);
8495 percpu_counter_destroy(&tctx->inflight);
8497 tsk->io_uring = NULL;
8500 static int io_sq_offload_create(struct io_ring_ctx *ctx,
8501 struct io_uring_params *p)
8505 /* Retain compatibility with failing for an invalid attach attempt */
8506 if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
8507 IORING_SETUP_ATTACH_WQ) {
8510 f = fdget(p->wq_fd);
8513 if (f.file->f_op != &io_uring_fops) {
8519 if (ctx->flags & IORING_SETUP_SQPOLL) {
8520 struct task_struct *tsk;
8521 struct io_sq_data *sqd;
8524 sqd = io_get_sq_data(p, &attached);
8530 ctx->sq_creds = get_current_cred();
8532 ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
8533 if (!ctx->sq_thread_idle)
8534 ctx->sq_thread_idle = HZ;
8536 io_sq_thread_park(sqd);
8537 list_add(&ctx->sqd_list, &sqd->ctx_list);
8538 io_sqd_update_thread_idle(sqd);
8539 /* don't attach to a dying SQPOLL thread, would be racy */
8540 ret = (attached && !sqd->thread) ? -ENXIO : 0;
8541 io_sq_thread_unpark(sqd);
8548 if (p->flags & IORING_SETUP_SQ_AFF) {
8549 int cpu = p->sq_thread_cpu;
8552 if (cpu >= nr_cpu_ids || !cpu_online(cpu))
8559 sqd->task_pid = current->pid;
8560 sqd->task_tgid = current->tgid;
8561 tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
8568 ret = io_uring_alloc_task_context(tsk, ctx);
8569 wake_up_new_task(tsk);
8572 } else if (p->flags & IORING_SETUP_SQ_AFF) {
8573 /* Can't have SQ_AFF without SQPOLL */
8580 complete(&ctx->sq_data->exited);
8582 io_sq_thread_finish(ctx);
8586 static inline void __io_unaccount_mem(struct user_struct *user,
8587 unsigned long nr_pages)
8589 atomic_long_sub(nr_pages, &user->locked_vm);
8592 static inline int __io_account_mem(struct user_struct *user,
8593 unsigned long nr_pages)
8595 unsigned long page_limit, cur_pages, new_pages;
8597 /* Don't allow more pages than we can safely lock */
8598 page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
8601 cur_pages = atomic_long_read(&user->locked_vm);
8602 new_pages = cur_pages + nr_pages;
8603 if (new_pages > page_limit)
8605 } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
8606 new_pages) != cur_pages);
8611 static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
8614 __io_unaccount_mem(ctx->user, nr_pages);
8616 if (ctx->mm_account)
8617 atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
8620 static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
8625 ret = __io_account_mem(ctx->user, nr_pages);
8630 if (ctx->mm_account)
8631 atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
8636 static void io_mem_free(void *ptr)
8643 page = virt_to_head_page(ptr);
8644 if (put_page_testzero(page))
8645 free_compound_page(page);
8648 static void *io_mem_alloc(size_t size)
8650 gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP |
8651 __GFP_NORETRY | __GFP_ACCOUNT;
8653 return (void *) __get_free_pages(gfp_flags, get_order(size));
8656 static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
8659 struct io_rings *rings;
8660 size_t off, sq_array_size;
8662 off = struct_size(rings, cqes, cq_entries);
8663 if (off == SIZE_MAX)
8667 off = ALIGN(off, SMP_CACHE_BYTES);
8675 sq_array_size = array_size(sizeof(u32), sq_entries);
8676 if (sq_array_size == SIZE_MAX)
8679 if (check_add_overflow(off, sq_array_size, &off))
8685 static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot)
8687 struct io_mapped_ubuf *imu = *slot;
8690 if (imu != ctx->dummy_ubuf) {
8691 for (i = 0; i < imu->nr_bvecs; i++)
8692 unpin_user_page(imu->bvec[i].bv_page);
8693 if (imu->acct_pages)
8694 io_unaccount_mem(ctx, imu->acct_pages);
8700 static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
8702 io_buffer_unmap(ctx, &prsrc->buf);
8706 static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
8710 for (i = 0; i < ctx->nr_user_bufs; i++)
8711 io_buffer_unmap(ctx, &ctx->user_bufs[i]);
8712 kfree(ctx->user_bufs);
8713 io_rsrc_data_free(ctx->buf_data);
8714 ctx->user_bufs = NULL;
8715 ctx->buf_data = NULL;
8716 ctx->nr_user_bufs = 0;
8719 static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
8726 ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx);
8728 __io_sqe_buffers_unregister(ctx);
8732 static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
8733 void __user *arg, unsigned index)
8735 struct iovec __user *src;
8737 #ifdef CONFIG_COMPAT
8739 struct compat_iovec __user *ciovs;
8740 struct compat_iovec ciov;
8742 ciovs = (struct compat_iovec __user *) arg;
8743 if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
8746 dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
8747 dst->iov_len = ciov.iov_len;
8751 src = (struct iovec __user *) arg;
8752 if (copy_from_user(dst, &src[index], sizeof(*dst)))
8758 * Not super efficient, but this is just a registration time. And we do cache
8759 * the last compound head, so generally we'll only do a full search if we don't
8762 * We check if the given compound head page has already been accounted, to
8763 * avoid double accounting it. This allows us to account the full size of the
8764 * page, not just the constituent pages of a huge page.
8766 static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
8767 int nr_pages, struct page *hpage)
8771 /* check current page array */
8772 for (i = 0; i < nr_pages; i++) {
8773 if (!PageCompound(pages[i]))
8775 if (compound_head(pages[i]) == hpage)
8779 /* check previously registered pages */
8780 for (i = 0; i < ctx->nr_user_bufs; i++) {
8781 struct io_mapped_ubuf *imu = ctx->user_bufs[i];
8783 for (j = 0; j < imu->nr_bvecs; j++) {
8784 if (!PageCompound(imu->bvec[j].bv_page))
8786 if (compound_head(imu->bvec[j].bv_page) == hpage)
8794 static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
8795 int nr_pages, struct io_mapped_ubuf *imu,
8796 struct page **last_hpage)
8800 imu->acct_pages = 0;
8801 for (i = 0; i < nr_pages; i++) {
8802 if (!PageCompound(pages[i])) {
8807 hpage = compound_head(pages[i]);
8808 if (hpage == *last_hpage)
8810 *last_hpage = hpage;
8811 if (headpage_already_acct(ctx, pages, i, hpage))
8813 imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
8817 if (!imu->acct_pages)
8820 ret = io_account_mem(ctx, imu->acct_pages);
8822 imu->acct_pages = 0;
8826 static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
8827 struct io_mapped_ubuf **pimu,
8828 struct page **last_hpage)
8830 struct io_mapped_ubuf *imu = NULL;
8831 struct vm_area_struct **vmas = NULL;
8832 struct page **pages = NULL;
8833 unsigned long off, start, end, ubuf;
8835 int ret, pret, nr_pages, i;
8837 if (!iov->iov_base) {
8838 *pimu = ctx->dummy_ubuf;
8842 ubuf = (unsigned long) iov->iov_base;
8843 end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
8844 start = ubuf >> PAGE_SHIFT;
8845 nr_pages = end - start;
8850 pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
8854 vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
8859 imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL);
8864 mmap_read_lock(current->mm);
8865 pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
8867 if (pret == nr_pages) {
8868 /* don't support file backed memory */
8869 for (i = 0; i < nr_pages; i++) {
8870 struct vm_area_struct *vma = vmas[i];
8872 if (vma_is_shmem(vma))
8875 !is_file_hugepages(vma->vm_file)) {
8881 ret = pret < 0 ? pret : -EFAULT;
8883 mmap_read_unlock(current->mm);
8886 * if we did partial map, or found file backed vmas,
8887 * release any pages we did get
8890 unpin_user_pages(pages, pret);
8894 ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage);
8896 unpin_user_pages(pages, pret);
8900 off = ubuf & ~PAGE_MASK;
8901 size = iov->iov_len;
8902 for (i = 0; i < nr_pages; i++) {
8905 vec_len = min_t(size_t, size, PAGE_SIZE - off);
8906 imu->bvec[i].bv_page = pages[i];
8907 imu->bvec[i].bv_len = vec_len;
8908 imu->bvec[i].bv_offset = off;
8912 /* store original address for later verification */
8914 imu->ubuf_end = ubuf + iov->iov_len;
8915 imu->nr_bvecs = nr_pages;
8926 static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
8928 ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL);
8929 return ctx->user_bufs ? 0 : -ENOMEM;
8932 static int io_buffer_validate(struct iovec *iov)
8934 unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1);
8937 * Don't impose further limits on the size and buffer
8938 * constraints here, we'll -EINVAL later when IO is
8939 * submitted if they are wrong.
8942 return iov->iov_len ? -EFAULT : 0;
8946 /* arbitrary limit, but we need something */
8947 if (iov->iov_len > SZ_1G)
8950 if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp))
8956 static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
8957 unsigned int nr_args, u64 __user *tags)
8959 struct page *last_hpage = NULL;
8960 struct io_rsrc_data *data;
8966 if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS)
8968 ret = io_rsrc_node_switch_start(ctx);
8971 ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data);
8974 ret = io_buffers_map_alloc(ctx, nr_args);
8976 io_rsrc_data_free(data);
8980 for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) {
8981 ret = io_copy_iov(ctx, &iov, arg, i);
8984 ret = io_buffer_validate(&iov);
8987 if (!iov.iov_base && *io_get_tag_slot(data, i)) {
8992 ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i],
8998 WARN_ON_ONCE(ctx->buf_data);
9000 ctx->buf_data = data;
9002 __io_sqe_buffers_unregister(ctx);
9004 io_rsrc_node_switch(ctx, NULL);
9008 static int __io_sqe_buffers_update(struct io_ring_ctx *ctx,
9009 struct io_uring_rsrc_update2 *up,
9010 unsigned int nr_args)
9012 u64 __user *tags = u64_to_user_ptr(up->tags);
9013 struct iovec iov, __user *iovs = u64_to_user_ptr(up->data);
9014 struct page *last_hpage = NULL;
9015 bool needs_switch = false;
9021 if (up->offset + nr_args > ctx->nr_user_bufs)
9024 for (done = 0; done < nr_args; done++) {
9025 struct io_mapped_ubuf *imu;
9026 int offset = up->offset + done;
9029 err = io_copy_iov(ctx, &iov, iovs, done);
9032 if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) {
9036 err = io_buffer_validate(&iov);
9039 if (!iov.iov_base && tag) {
9043 err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage);
9047 i = array_index_nospec(offset, ctx->nr_user_bufs);
9048 if (ctx->user_bufs[i] != ctx->dummy_ubuf) {
9049 err = io_queue_rsrc_removal(ctx->buf_data, offset,
9050 ctx->rsrc_node, ctx->user_bufs[i]);
9051 if (unlikely(err)) {
9052 io_buffer_unmap(ctx, &imu);
9055 ctx->user_bufs[i] = NULL;
9056 needs_switch = true;
9059 ctx->user_bufs[i] = imu;
9060 *io_get_tag_slot(ctx->buf_data, offset) = tag;
9064 io_rsrc_node_switch(ctx, ctx->buf_data);
9065 return done ? done : err;
9068 static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
9070 __s32 __user *fds = arg;
9076 if (copy_from_user(&fd, fds, sizeof(*fds)))
9079 ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
9080 if (IS_ERR(ctx->cq_ev_fd)) {
9081 int ret = PTR_ERR(ctx->cq_ev_fd);
9083 ctx->cq_ev_fd = NULL;
9090 static int io_eventfd_unregister(struct io_ring_ctx *ctx)
9092 if (ctx->cq_ev_fd) {
9093 eventfd_ctx_put(ctx->cq_ev_fd);
9094 ctx->cq_ev_fd = NULL;
9101 static void io_destroy_buffers(struct io_ring_ctx *ctx)
9103 struct io_buffer *buf;
9104 unsigned long index;
9106 xa_for_each(&ctx->io_buffers, index, buf)
9107 __io_remove_buffers(ctx, buf, index, -1U);
9110 static void io_req_cache_free(struct list_head *list)
9112 struct io_kiocb *req, *nxt;
9114 list_for_each_entry_safe(req, nxt, list, inflight_entry) {
9115 list_del(&req->inflight_entry);
9116 kmem_cache_free(req_cachep, req);
9120 static void io_req_caches_free(struct io_ring_ctx *ctx)
9122 struct io_submit_state *state = &ctx->submit_state;
9124 mutex_lock(&ctx->uring_lock);
9126 if (state->free_reqs) {
9127 kmem_cache_free_bulk(req_cachep, state->free_reqs, state->reqs);
9128 state->free_reqs = 0;
9131 io_flush_cached_locked_reqs(ctx, state);
9132 io_req_cache_free(&state->free_list);
9133 mutex_unlock(&ctx->uring_lock);
9136 static void io_wait_rsrc_data(struct io_rsrc_data *data)
9138 if (data && !atomic_dec_and_test(&data->refs))
9139 wait_for_completion(&data->done);
9142 static void io_ring_ctx_free(struct io_ring_ctx *ctx)
9144 io_sq_thread_finish(ctx);
9146 if (ctx->mm_account) {
9147 mmdrop(ctx->mm_account);
9148 ctx->mm_account = NULL;
9151 /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */
9152 io_wait_rsrc_data(ctx->buf_data);
9153 io_wait_rsrc_data(ctx->file_data);
9155 mutex_lock(&ctx->uring_lock);
9157 __io_sqe_buffers_unregister(ctx);
9159 __io_sqe_files_unregister(ctx);
9161 __io_cqring_overflow_flush(ctx, true);
9162 mutex_unlock(&ctx->uring_lock);
9163 io_eventfd_unregister(ctx);
9164 io_destroy_buffers(ctx);
9166 put_cred(ctx->sq_creds);
9168 /* there are no registered resources left, nobody uses it */
9170 io_rsrc_node_destroy(ctx->rsrc_node);
9171 if (ctx->rsrc_backup_node)
9172 io_rsrc_node_destroy(ctx->rsrc_backup_node);
9173 flush_delayed_work(&ctx->rsrc_put_work);
9175 WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list));
9176 WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist));
9178 #if defined(CONFIG_UNIX)
9179 if (ctx->ring_sock) {
9180 ctx->ring_sock->file = NULL; /* so that iput() is called */
9181 sock_release(ctx->ring_sock);
9184 WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list));
9186 io_mem_free(ctx->rings);
9187 io_mem_free(ctx->sq_sqes);
9189 percpu_ref_exit(&ctx->refs);
9190 free_uid(ctx->user);
9191 io_req_caches_free(ctx);
9193 io_wq_put_hash(ctx->hash_map);
9194 kfree(ctx->cancel_hash);
9195 kfree(ctx->dummy_ubuf);
9199 static __poll_t io_uring_poll(struct file *file, poll_table *wait)
9201 struct io_ring_ctx *ctx = file->private_data;
9204 poll_wait(file, &ctx->poll_wait, wait);
9206 * synchronizes with barrier from wq_has_sleeper call in
9210 if (!io_sqring_full(ctx))
9211 mask |= EPOLLOUT | EPOLLWRNORM;
9214 * Don't flush cqring overflow list here, just do a simple check.
9215 * Otherwise there could possible be ABBA deadlock:
9218 * lock(&ctx->uring_lock);
9220 * lock(&ctx->uring_lock);
9223 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
9224 * pushs them to do the flush.
9226 if (io_cqring_events(ctx) || test_bit(0, &ctx->check_cq_overflow))
9227 mask |= EPOLLIN | EPOLLRDNORM;
9232 static int io_uring_fasync(int fd, struct file *file, int on)
9234 struct io_ring_ctx *ctx = file->private_data;
9236 return fasync_helper(fd, file, on, &ctx->cq_fasync);
9239 static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
9241 const struct cred *creds;
9243 creds = xa_erase(&ctx->personalities, id);
9252 struct io_tctx_exit {
9253 struct callback_head task_work;
9254 struct completion completion;
9255 struct io_ring_ctx *ctx;
9258 static void io_tctx_exit_cb(struct callback_head *cb)
9260 struct io_uring_task *tctx = current->io_uring;
9261 struct io_tctx_exit *work;
9263 work = container_of(cb, struct io_tctx_exit, task_work);
9265 * When @in_idle, we're in cancellation and it's racy to remove the
9266 * node. It'll be removed by the end of cancellation, just ignore it.
9268 if (!atomic_read(&tctx->in_idle))
9269 io_uring_del_tctx_node((unsigned long)work->ctx);
9270 complete(&work->completion);
9273 static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
9275 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
9277 return req->ctx == data;
9280 static void io_ring_exit_work(struct work_struct *work)
9282 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
9283 unsigned long timeout = jiffies + HZ * 60 * 5;
9284 unsigned long interval = HZ / 20;
9285 struct io_tctx_exit exit;
9286 struct io_tctx_node *node;
9290 * If we're doing polled IO and end up having requests being
9291 * submitted async (out-of-line), then completions can come in while
9292 * we're waiting for refs to drop. We need to reap these manually,
9293 * as nobody else will be looking for them.
9296 io_uring_try_cancel_requests(ctx, NULL, true);
9298 struct io_sq_data *sqd = ctx->sq_data;
9299 struct task_struct *tsk;
9301 io_sq_thread_park(sqd);
9303 if (tsk && tsk->io_uring && tsk->io_uring->io_wq)
9304 io_wq_cancel_cb(tsk->io_uring->io_wq,
9305 io_cancel_ctx_cb, ctx, true);
9306 io_sq_thread_unpark(sqd);
9309 if (WARN_ON_ONCE(time_after(jiffies, timeout))) {
9310 /* there is little hope left, don't run it too often */
9313 } while (!wait_for_completion_timeout(&ctx->ref_comp, interval));
9315 init_completion(&exit.completion);
9316 init_task_work(&exit.task_work, io_tctx_exit_cb);
9319 * Some may use context even when all refs and requests have been put,
9320 * and they are free to do so while still holding uring_lock or
9321 * completion_lock, see io_req_task_submit(). Apart from other work,
9322 * this lock/unlock section also waits them to finish.
9324 mutex_lock(&ctx->uring_lock);
9325 while (!list_empty(&ctx->tctx_list)) {
9326 WARN_ON_ONCE(time_after(jiffies, timeout));
9328 node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
9330 /* don't spin on a single task if cancellation failed */
9331 list_rotate_left(&ctx->tctx_list);
9332 ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
9333 if (WARN_ON_ONCE(ret))
9335 wake_up_process(node->task);
9337 mutex_unlock(&ctx->uring_lock);
9338 wait_for_completion(&exit.completion);
9339 mutex_lock(&ctx->uring_lock);
9341 mutex_unlock(&ctx->uring_lock);
9342 spin_lock(&ctx->completion_lock);
9343 spin_unlock(&ctx->completion_lock);
9345 io_ring_ctx_free(ctx);
9348 /* Returns true if we found and killed one or more timeouts */
9349 static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk,
9352 struct io_kiocb *req, *tmp;
9355 spin_lock(&ctx->completion_lock);
9356 spin_lock_irq(&ctx->timeout_lock);
9357 list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
9358 if (io_match_task(req, tsk, cancel_all)) {
9359 io_kill_timeout(req, -ECANCELED);
9363 spin_unlock_irq(&ctx->timeout_lock);
9365 io_commit_cqring(ctx);
9366 spin_unlock(&ctx->completion_lock);
9368 io_cqring_ev_posted(ctx);
9369 return canceled != 0;
9372 static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
9374 unsigned long index;
9375 struct creds *creds;
9377 mutex_lock(&ctx->uring_lock);
9378 percpu_ref_kill(&ctx->refs);
9380 __io_cqring_overflow_flush(ctx, true);
9381 xa_for_each(&ctx->personalities, index, creds)
9382 io_unregister_personality(ctx, index);
9383 mutex_unlock(&ctx->uring_lock);
9385 io_kill_timeouts(ctx, NULL, true);
9386 io_poll_remove_all(ctx, NULL, true);
9388 /* if we failed setting up the ctx, we might not have any rings */
9389 io_iopoll_try_reap_events(ctx);
9391 INIT_WORK(&ctx->exit_work, io_ring_exit_work);
9393 * Use system_unbound_wq to avoid spawning tons of event kworkers
9394 * if we're exiting a ton of rings at the same time. It just adds
9395 * noise and overhead, there's no discernable change in runtime
9396 * over using system_wq.
9398 queue_work(system_unbound_wq, &ctx->exit_work);
9401 static int io_uring_release(struct inode *inode, struct file *file)
9403 struct io_ring_ctx *ctx = file->private_data;
9405 file->private_data = NULL;
9406 io_ring_ctx_wait_and_kill(ctx);
9410 struct io_task_cancel {
9411 struct task_struct *task;
9415 static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
9417 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
9418 struct io_task_cancel *cancel = data;
9421 if (!cancel->all && (req->flags & REQ_F_LINK_TIMEOUT)) {
9422 struct io_ring_ctx *ctx = req->ctx;
9424 /* protect against races with linked timeouts */
9425 spin_lock(&ctx->completion_lock);
9426 ret = io_match_task(req, cancel->task, cancel->all);
9427 spin_unlock(&ctx->completion_lock);
9429 ret = io_match_task(req, cancel->task, cancel->all);
9434 static bool io_cancel_defer_files(struct io_ring_ctx *ctx,
9435 struct task_struct *task, bool cancel_all)
9437 struct io_defer_entry *de;
9440 spin_lock(&ctx->completion_lock);
9441 list_for_each_entry_reverse(de, &ctx->defer_list, list) {
9442 if (io_match_task(de->req, task, cancel_all)) {
9443 list_cut_position(&list, &ctx->defer_list, &de->list);
9447 spin_unlock(&ctx->completion_lock);
9448 if (list_empty(&list))
9451 while (!list_empty(&list)) {
9452 de = list_first_entry(&list, struct io_defer_entry, list);
9453 list_del_init(&de->list);
9454 io_req_complete_failed(de->req, -ECANCELED);
9460 static bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
9462 struct io_tctx_node *node;
9463 enum io_wq_cancel cret;
9466 mutex_lock(&ctx->uring_lock);
9467 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
9468 struct io_uring_task *tctx = node->task->io_uring;
9471 * io_wq will stay alive while we hold uring_lock, because it's
9472 * killed after ctx nodes, which requires to take the lock.
9474 if (!tctx || !tctx->io_wq)
9476 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
9477 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
9479 mutex_unlock(&ctx->uring_lock);
9484 static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
9485 struct task_struct *task,
9488 struct io_task_cancel cancel = { .task = task, .all = cancel_all, };
9489 struct io_uring_task *tctx = task ? task->io_uring : NULL;
9492 enum io_wq_cancel cret;
9496 ret |= io_uring_try_cancel_iowq(ctx);
9497 } else if (tctx && tctx->io_wq) {
9499 * Cancels requests of all rings, not only @ctx, but
9500 * it's fine as the task is in exit/exec.
9502 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
9504 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
9507 /* SQPOLL thread does its own polling */
9508 if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) ||
9509 (ctx->sq_data && ctx->sq_data->thread == current)) {
9510 while (!list_empty_careful(&ctx->iopoll_list)) {
9511 io_iopoll_try_reap_events(ctx);
9516 ret |= io_cancel_defer_files(ctx, task, cancel_all);
9517 ret |= io_poll_remove_all(ctx, task, cancel_all);
9518 ret |= io_kill_timeouts(ctx, task, cancel_all);
9520 ret |= io_run_task_work();
9527 static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
9529 struct io_uring_task *tctx = current->io_uring;
9530 struct io_tctx_node *node;
9533 if (unlikely(!tctx)) {
9534 ret = io_uring_alloc_task_context(current, ctx);
9537 tctx = current->io_uring;
9539 if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
9540 node = kmalloc(sizeof(*node), GFP_KERNEL);
9544 node->task = current;
9546 ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
9553 mutex_lock(&ctx->uring_lock);
9554 list_add(&node->ctx_node, &ctx->tctx_list);
9555 mutex_unlock(&ctx->uring_lock);
9562 * Note that this task has used io_uring. We use it for cancelation purposes.
9564 static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
9566 struct io_uring_task *tctx = current->io_uring;
9568 if (likely(tctx && tctx->last == ctx))
9570 return __io_uring_add_tctx_node(ctx);
9574 * Remove this io_uring_file -> task mapping.
9576 static void io_uring_del_tctx_node(unsigned long index)
9578 struct io_uring_task *tctx = current->io_uring;
9579 struct io_tctx_node *node;
9583 node = xa_erase(&tctx->xa, index);
9587 WARN_ON_ONCE(current != node->task);
9588 WARN_ON_ONCE(list_empty(&node->ctx_node));
9590 mutex_lock(&node->ctx->uring_lock);
9591 list_del(&node->ctx_node);
9592 mutex_unlock(&node->ctx->uring_lock);
9594 if (tctx->last == node->ctx)
9599 static void io_uring_clean_tctx(struct io_uring_task *tctx)
9601 struct io_wq *wq = tctx->io_wq;
9602 struct io_tctx_node *node;
9603 unsigned long index;
9605 xa_for_each(&tctx->xa, index, node)
9606 io_uring_del_tctx_node(index);
9609 * Must be after io_uring_del_task_file() (removes nodes under
9610 * uring_lock) to avoid race with io_uring_try_cancel_iowq().
9612 io_wq_put_and_exit(wq);
9617 static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
9620 return atomic_read(&tctx->inflight_tracked);
9621 return percpu_counter_sum(&tctx->inflight);
9624 static void io_uring_drop_tctx_refs(struct task_struct *task)
9626 struct io_uring_task *tctx = task->io_uring;
9627 unsigned int refs = tctx->cached_refs;
9630 tctx->cached_refs = 0;
9631 percpu_counter_sub(&tctx->inflight, refs);
9632 put_task_struct_many(task, refs);
9637 * Find any io_uring ctx that this task has registered or done IO on, and cancel
9638 * requests. @sqd should be not-null IIF it's an SQPOLL thread cancellation.
9640 static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd)
9642 struct io_uring_task *tctx = current->io_uring;
9643 struct io_ring_ctx *ctx;
9647 WARN_ON_ONCE(sqd && sqd->thread != current);
9649 if (!current->io_uring)
9652 io_wq_exit_start(tctx->io_wq);
9654 atomic_inc(&tctx->in_idle);
9656 io_uring_drop_tctx_refs(current);
9657 /* read completions before cancelations */
9658 inflight = tctx_inflight(tctx, !cancel_all);
9663 struct io_tctx_node *node;
9664 unsigned long index;
9666 xa_for_each(&tctx->xa, index, node) {
9667 /* sqpoll task will cancel all its requests */
9668 if (node->ctx->sq_data)
9670 io_uring_try_cancel_requests(node->ctx, current,
9674 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
9675 io_uring_try_cancel_requests(ctx, current,
9679 prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE);
9680 io_uring_drop_tctx_refs(current);
9682 * If we've seen completions, retry without waiting. This
9683 * avoids a race where a completion comes in before we did
9684 * prepare_to_wait().
9686 if (inflight == tctx_inflight(tctx, !cancel_all))
9688 finish_wait(&tctx->wait, &wait);
9690 atomic_dec(&tctx->in_idle);
9692 io_uring_clean_tctx(tctx);
9694 /* for exec all current's requests should be gone, kill tctx */
9695 __io_uring_free(current);
9699 void __io_uring_cancel(bool cancel_all)
9701 io_uring_cancel_generic(cancel_all, NULL);
9704 static void *io_uring_validate_mmap_request(struct file *file,
9705 loff_t pgoff, size_t sz)
9707 struct io_ring_ctx *ctx = file->private_data;
9708 loff_t offset = pgoff << PAGE_SHIFT;
9713 case IORING_OFF_SQ_RING:
9714 case IORING_OFF_CQ_RING:
9717 case IORING_OFF_SQES:
9721 return ERR_PTR(-EINVAL);
9724 page = virt_to_head_page(ptr);
9725 if (sz > page_size(page))
9726 return ERR_PTR(-EINVAL);
9733 static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
9735 size_t sz = vma->vm_end - vma->vm_start;
9739 ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
9741 return PTR_ERR(ptr);
9743 pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
9744 return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
9747 #else /* !CONFIG_MMU */
9749 static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
9751 return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
9754 static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
9756 return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
9759 static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
9760 unsigned long addr, unsigned long len,
9761 unsigned long pgoff, unsigned long flags)
9765 ptr = io_uring_validate_mmap_request(file, pgoff, len);
9767 return PTR_ERR(ptr);
9769 return (unsigned long) ptr;
9772 #endif /* !CONFIG_MMU */
9774 static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
9779 if (!io_sqring_full(ctx))
9781 prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
9783 if (!io_sqring_full(ctx))
9786 } while (!signal_pending(current));
9788 finish_wait(&ctx->sqo_sq_wait, &wait);
9792 static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
9793 struct __kernel_timespec __user **ts,
9794 const sigset_t __user **sig)
9796 struct io_uring_getevents_arg arg;
9799 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
9800 * is just a pointer to the sigset_t.
9802 if (!(flags & IORING_ENTER_EXT_ARG)) {
9803 *sig = (const sigset_t __user *) argp;
9809 * EXT_ARG is set - ensure we agree on the size of it and copy in our
9810 * timespec and sigset_t pointers if good.
9812 if (*argsz != sizeof(arg))
9814 if (copy_from_user(&arg, argp, sizeof(arg)))
9816 *sig = u64_to_user_ptr(arg.sigmask);
9817 *argsz = arg.sigmask_sz;
9818 *ts = u64_to_user_ptr(arg.ts);
9822 SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
9823 u32, min_complete, u32, flags, const void __user *, argp,
9826 struct io_ring_ctx *ctx;
9833 if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
9834 IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG)))
9838 if (unlikely(!f.file))
9842 if (unlikely(f.file->f_op != &io_uring_fops))
9846 ctx = f.file->private_data;
9847 if (unlikely(!percpu_ref_tryget(&ctx->refs)))
9851 if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED))
9855 * For SQ polling, the thread will do all submissions and completions.
9856 * Just return the requested submit count, and wake the thread if
9860 if (ctx->flags & IORING_SETUP_SQPOLL) {
9861 io_cqring_overflow_flush(ctx);
9863 if (unlikely(ctx->sq_data->thread == NULL)) {
9867 if (flags & IORING_ENTER_SQ_WAKEUP)
9868 wake_up(&ctx->sq_data->wait);
9869 if (flags & IORING_ENTER_SQ_WAIT) {
9870 ret = io_sqpoll_wait_sq(ctx);
9874 submitted = to_submit;
9875 } else if (to_submit) {
9876 ret = io_uring_add_tctx_node(ctx);
9879 mutex_lock(&ctx->uring_lock);
9880 submitted = io_submit_sqes(ctx, to_submit);
9881 mutex_unlock(&ctx->uring_lock);
9883 if (submitted != to_submit)
9886 if (flags & IORING_ENTER_GETEVENTS) {
9887 const sigset_t __user *sig;
9888 struct __kernel_timespec __user *ts;
9890 ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
9894 min_complete = min(min_complete, ctx->cq_entries);
9897 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
9898 * space applications don't need to do io completion events
9899 * polling again, they can rely on io_sq_thread to do polling
9900 * work, which can reduce cpu usage and uring_lock contention.
9902 if (ctx->flags & IORING_SETUP_IOPOLL &&
9903 !(ctx->flags & IORING_SETUP_SQPOLL)) {
9904 ret = io_iopoll_check(ctx, min_complete);
9906 ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts);
9911 percpu_ref_put(&ctx->refs);
9914 return submitted ? submitted : ret;
9917 #ifdef CONFIG_PROC_FS
9918 static int io_uring_show_cred(struct seq_file *m, unsigned int id,
9919 const struct cred *cred)
9921 struct user_namespace *uns = seq_user_ns(m);
9922 struct group_info *gi;
9927 seq_printf(m, "%5d\n", id);
9928 seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
9929 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
9930 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
9931 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
9932 seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
9933 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
9934 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
9935 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
9936 seq_puts(m, "\n\tGroups:\t");
9937 gi = cred->group_info;
9938 for (g = 0; g < gi->ngroups; g++) {
9939 seq_put_decimal_ull(m, g ? " " : "",
9940 from_kgid_munged(uns, gi->gid[g]));
9942 seq_puts(m, "\n\tCapEff:\t");
9943 cap = cred->cap_effective;
9944 CAP_FOR_EACH_U32(__capi)
9945 seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
9950 static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m)
9952 struct io_sq_data *sq = NULL;
9957 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
9958 * since fdinfo case grabs it in the opposite direction of normal use
9959 * cases. If we fail to get the lock, we just don't iterate any
9960 * structures that could be going away outside the io_uring mutex.
9962 has_lock = mutex_trylock(&ctx->uring_lock);
9964 if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
9970 seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
9971 seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
9972 seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
9973 for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
9974 struct file *f = io_file_from_index(ctx, i);
9977 seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
9979 seq_printf(m, "%5u: <none>\n", i);
9981 seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
9982 for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
9983 struct io_mapped_ubuf *buf = ctx->user_bufs[i];
9984 unsigned int len = buf->ubuf_end - buf->ubuf;
9986 seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
9988 if (has_lock && !xa_empty(&ctx->personalities)) {
9989 unsigned long index;
9990 const struct cred *cred;
9992 seq_printf(m, "Personalities:\n");
9993 xa_for_each(&ctx->personalities, index, cred)
9994 io_uring_show_cred(m, index, cred);
9996 seq_printf(m, "PollList:\n");
9997 spin_lock(&ctx->completion_lock);
9998 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
9999 struct hlist_head *list = &ctx->cancel_hash[i];
10000 struct io_kiocb *req;
10002 hlist_for_each_entry(req, list, hash_node)
10003 seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
10004 req->task->task_works != NULL);
10006 spin_unlock(&ctx->completion_lock);
10008 mutex_unlock(&ctx->uring_lock);
10011 static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
10013 struct io_ring_ctx *ctx = f->private_data;
10015 if (percpu_ref_tryget(&ctx->refs)) {
10016 __io_uring_show_fdinfo(ctx, m);
10017 percpu_ref_put(&ctx->refs);
10022 static const struct file_operations io_uring_fops = {
10023 .release = io_uring_release,
10024 .mmap = io_uring_mmap,
10026 .get_unmapped_area = io_uring_nommu_get_unmapped_area,
10027 .mmap_capabilities = io_uring_nommu_mmap_capabilities,
10029 .poll = io_uring_poll,
10030 .fasync = io_uring_fasync,
10031 #ifdef CONFIG_PROC_FS
10032 .show_fdinfo = io_uring_show_fdinfo,
10036 static int io_allocate_scq_urings(struct io_ring_ctx *ctx,
10037 struct io_uring_params *p)
10039 struct io_rings *rings;
10040 size_t size, sq_array_offset;
10042 /* make sure these are sane, as we already accounted them */
10043 ctx->sq_entries = p->sq_entries;
10044 ctx->cq_entries = p->cq_entries;
10046 size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
10047 if (size == SIZE_MAX)
10050 rings = io_mem_alloc(size);
10054 ctx->rings = rings;
10055 ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
10056 rings->sq_ring_mask = p->sq_entries - 1;
10057 rings->cq_ring_mask = p->cq_entries - 1;
10058 rings->sq_ring_entries = p->sq_entries;
10059 rings->cq_ring_entries = p->cq_entries;
10061 size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
10062 if (size == SIZE_MAX) {
10063 io_mem_free(ctx->rings);
10068 ctx->sq_sqes = io_mem_alloc(size);
10069 if (!ctx->sq_sqes) {
10070 io_mem_free(ctx->rings);
10078 static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
10082 fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
10086 ret = io_uring_add_tctx_node(ctx);
10091 fd_install(fd, file);
10096 * Allocate an anonymous fd, this is what constitutes the application
10097 * visible backing of an io_uring instance. The application mmaps this
10098 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
10099 * we have to tie this fd to a socket for file garbage collection purposes.
10101 static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
10104 #if defined(CONFIG_UNIX)
10107 ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
10110 return ERR_PTR(ret);
10113 file = anon_inode_getfile("[io_uring]", &io_uring_fops, ctx,
10114 O_RDWR | O_CLOEXEC);
10115 #if defined(CONFIG_UNIX)
10116 if (IS_ERR(file)) {
10117 sock_release(ctx->ring_sock);
10118 ctx->ring_sock = NULL;
10120 ctx->ring_sock->file = file;
10126 static int io_uring_create(unsigned entries, struct io_uring_params *p,
10127 struct io_uring_params __user *params)
10129 struct io_ring_ctx *ctx;
10135 if (entries > IORING_MAX_ENTRIES) {
10136 if (!(p->flags & IORING_SETUP_CLAMP))
10138 entries = IORING_MAX_ENTRIES;
10142 * Use twice as many entries for the CQ ring. It's possible for the
10143 * application to drive a higher depth than the size of the SQ ring,
10144 * since the sqes are only used at submission time. This allows for
10145 * some flexibility in overcommitting a bit. If the application has
10146 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
10147 * of CQ ring entries manually.
10149 p->sq_entries = roundup_pow_of_two(entries);
10150 if (p->flags & IORING_SETUP_CQSIZE) {
10152 * If IORING_SETUP_CQSIZE is set, we do the same roundup
10153 * to a power-of-two, if it isn't already. We do NOT impose
10154 * any cq vs sq ring sizing.
10156 if (!p->cq_entries)
10158 if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
10159 if (!(p->flags & IORING_SETUP_CLAMP))
10161 p->cq_entries = IORING_MAX_CQ_ENTRIES;
10163 p->cq_entries = roundup_pow_of_two(p->cq_entries);
10164 if (p->cq_entries < p->sq_entries)
10167 p->cq_entries = 2 * p->sq_entries;
10170 ctx = io_ring_ctx_alloc(p);
10173 ctx->compat = in_compat_syscall();
10174 if (!capable(CAP_IPC_LOCK))
10175 ctx->user = get_uid(current_user());
10178 * This is just grabbed for accounting purposes. When a process exits,
10179 * the mm is exited and dropped before the files, hence we need to hang
10180 * on to this mm purely for the purposes of being able to unaccount
10181 * memory (locked/pinned vm). It's not used for anything else.
10183 mmgrab(current->mm);
10184 ctx->mm_account = current->mm;
10186 ret = io_allocate_scq_urings(ctx, p);
10190 ret = io_sq_offload_create(ctx, p);
10193 /* always set a rsrc node */
10194 ret = io_rsrc_node_switch_start(ctx);
10197 io_rsrc_node_switch(ctx, NULL);
10199 memset(&p->sq_off, 0, sizeof(p->sq_off));
10200 p->sq_off.head = offsetof(struct io_rings, sq.head);
10201 p->sq_off.tail = offsetof(struct io_rings, sq.tail);
10202 p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
10203 p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
10204 p->sq_off.flags = offsetof(struct io_rings, sq_flags);
10205 p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
10206 p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
10208 memset(&p->cq_off, 0, sizeof(p->cq_off));
10209 p->cq_off.head = offsetof(struct io_rings, cq.head);
10210 p->cq_off.tail = offsetof(struct io_rings, cq.tail);
10211 p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
10212 p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
10213 p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
10214 p->cq_off.cqes = offsetof(struct io_rings, cqes);
10215 p->cq_off.flags = offsetof(struct io_rings, cq_flags);
10217 p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
10218 IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
10219 IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
10220 IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
10221 IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS |
10222 IORING_FEAT_RSRC_TAGS;
10224 if (copy_to_user(params, p, sizeof(*p))) {
10229 file = io_uring_get_file(ctx);
10230 if (IS_ERR(file)) {
10231 ret = PTR_ERR(file);
10236 * Install ring fd as the very last thing, so we don't risk someone
10237 * having closed it before we finish setup
10239 ret = io_uring_install_fd(ctx, file);
10241 /* fput will clean it up */
10246 trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
10249 io_ring_ctx_wait_and_kill(ctx);
10254 * Sets up an aio uring context, and returns the fd. Applications asks for a
10255 * ring size, we return the actual sq/cq ring sizes (among other things) in the
10256 * params structure passed in.
10258 static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
10260 struct io_uring_params p;
10263 if (copy_from_user(&p, params, sizeof(p)))
10265 for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
10270 if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
10271 IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
10272 IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
10273 IORING_SETUP_R_DISABLED))
10276 return io_uring_create(entries, &p, params);
10279 SYSCALL_DEFINE2(io_uring_setup, u32, entries,
10280 struct io_uring_params __user *, params)
10282 return io_uring_setup(entries, params);
10285 static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)
10287 struct io_uring_probe *p;
10291 size = struct_size(p, ops, nr_args);
10292 if (size == SIZE_MAX)
10294 p = kzalloc(size, GFP_KERNEL);
10299 if (copy_from_user(p, arg, size))
10302 if (memchr_inv(p, 0, size))
10305 p->last_op = IORING_OP_LAST - 1;
10306 if (nr_args > IORING_OP_LAST)
10307 nr_args = IORING_OP_LAST;
10309 for (i = 0; i < nr_args; i++) {
10311 if (!io_op_defs[i].not_supported)
10312 p->ops[i].flags = IO_URING_OP_SUPPORTED;
10317 if (copy_to_user(arg, p, size))
10324 static int io_register_personality(struct io_ring_ctx *ctx)
10326 const struct cred *creds;
10330 creds = get_current_cred();
10332 ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
10333 XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
10341 static int io_register_restrictions(struct io_ring_ctx *ctx, void __user *arg,
10342 unsigned int nr_args)
10344 struct io_uring_restriction *res;
10348 /* Restrictions allowed only if rings started disabled */
10349 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
10352 /* We allow only a single restrictions registration */
10353 if (ctx->restrictions.registered)
10356 if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
10359 size = array_size(nr_args, sizeof(*res));
10360 if (size == SIZE_MAX)
10363 res = memdup_user(arg, size);
10365 return PTR_ERR(res);
10369 for (i = 0; i < nr_args; i++) {
10370 switch (res[i].opcode) {
10371 case IORING_RESTRICTION_REGISTER_OP:
10372 if (res[i].register_op >= IORING_REGISTER_LAST) {
10377 __set_bit(res[i].register_op,
10378 ctx->restrictions.register_op);
10380 case IORING_RESTRICTION_SQE_OP:
10381 if (res[i].sqe_op >= IORING_OP_LAST) {
10386 __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
10388 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
10389 ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
10391 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
10392 ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
10401 /* Reset all restrictions if an error happened */
10403 memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
10405 ctx->restrictions.registered = true;
10411 static int io_register_enable_rings(struct io_ring_ctx *ctx)
10413 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
10416 if (ctx->restrictions.registered)
10417 ctx->restricted = 1;
10419 ctx->flags &= ~IORING_SETUP_R_DISABLED;
10420 if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
10421 wake_up(&ctx->sq_data->wait);
10425 static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
10426 struct io_uring_rsrc_update2 *up,
10434 if (check_add_overflow(up->offset, nr_args, &tmp))
10436 err = io_rsrc_node_switch_start(ctx);
10441 case IORING_RSRC_FILE:
10442 return __io_sqe_files_update(ctx, up, nr_args);
10443 case IORING_RSRC_BUFFER:
10444 return __io_sqe_buffers_update(ctx, up, nr_args);
10449 static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
10452 struct io_uring_rsrc_update2 up;
10456 memset(&up, 0, sizeof(up));
10457 if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update)))
10459 return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args);
10462 static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
10463 unsigned size, unsigned type)
10465 struct io_uring_rsrc_update2 up;
10467 if (size != sizeof(up))
10469 if (copy_from_user(&up, arg, sizeof(up)))
10471 if (!up.nr || up.resv)
10473 return __io_register_rsrc_update(ctx, type, &up, up.nr);
10476 static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
10477 unsigned int size, unsigned int type)
10479 struct io_uring_rsrc_register rr;
10481 /* keep it extendible */
10482 if (size != sizeof(rr))
10485 memset(&rr, 0, sizeof(rr));
10486 if (copy_from_user(&rr, arg, size))
10488 if (!rr.nr || rr.resv || rr.resv2)
10492 case IORING_RSRC_FILE:
10493 return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data),
10494 rr.nr, u64_to_user_ptr(rr.tags));
10495 case IORING_RSRC_BUFFER:
10496 return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data),
10497 rr.nr, u64_to_user_ptr(rr.tags));
10502 static int io_register_iowq_aff(struct io_ring_ctx *ctx, void __user *arg,
10505 struct io_uring_task *tctx = current->io_uring;
10506 cpumask_var_t new_mask;
10509 if (!tctx || !tctx->io_wq)
10512 if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
10515 cpumask_clear(new_mask);
10516 if (len > cpumask_size())
10517 len = cpumask_size();
10519 if (copy_from_user(new_mask, arg, len)) {
10520 free_cpumask_var(new_mask);
10524 ret = io_wq_cpu_affinity(tctx->io_wq, new_mask);
10525 free_cpumask_var(new_mask);
10529 static int io_unregister_iowq_aff(struct io_ring_ctx *ctx)
10531 struct io_uring_task *tctx = current->io_uring;
10533 if (!tctx || !tctx->io_wq)
10536 return io_wq_cpu_affinity(tctx->io_wq, NULL);
10539 static int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
10542 struct io_uring_task *tctx = NULL;
10543 struct io_sq_data *sqd = NULL;
10544 __u32 new_count[2];
10547 if (copy_from_user(new_count, arg, sizeof(new_count)))
10549 for (i = 0; i < ARRAY_SIZE(new_count); i++)
10550 if (new_count[i] > INT_MAX)
10553 if (ctx->flags & IORING_SETUP_SQPOLL) {
10554 sqd = ctx->sq_data;
10557 * Observe the correct sqd->lock -> ctx->uring_lock
10558 * ordering. Fine to drop uring_lock here, we hold
10559 * a ref to the ctx.
10561 mutex_unlock(&ctx->uring_lock);
10562 mutex_lock(&sqd->lock);
10563 mutex_lock(&ctx->uring_lock);
10564 tctx = sqd->thread->io_uring;
10567 tctx = current->io_uring;
10571 if (!tctx || !tctx->io_wq)
10574 ret = io_wq_max_workers(tctx->io_wq, new_count);
10579 mutex_unlock(&sqd->lock);
10581 if (copy_to_user(arg, new_count, sizeof(new_count)))
10587 mutex_unlock(&sqd->lock);
10591 static bool io_register_op_must_quiesce(int op)
10594 case IORING_REGISTER_BUFFERS:
10595 case IORING_UNREGISTER_BUFFERS:
10596 case IORING_REGISTER_FILES:
10597 case IORING_UNREGISTER_FILES:
10598 case IORING_REGISTER_FILES_UPDATE:
10599 case IORING_REGISTER_PROBE:
10600 case IORING_REGISTER_PERSONALITY:
10601 case IORING_UNREGISTER_PERSONALITY:
10602 case IORING_REGISTER_FILES2:
10603 case IORING_REGISTER_FILES_UPDATE2:
10604 case IORING_REGISTER_BUFFERS2:
10605 case IORING_REGISTER_BUFFERS_UPDATE:
10606 case IORING_REGISTER_IOWQ_AFF:
10607 case IORING_UNREGISTER_IOWQ_AFF:
10608 case IORING_REGISTER_IOWQ_MAX_WORKERS:
10615 static int io_ctx_quiesce(struct io_ring_ctx *ctx)
10619 percpu_ref_kill(&ctx->refs);
10622 * Drop uring mutex before waiting for references to exit. If another
10623 * thread is currently inside io_uring_enter() it might need to grab the
10624 * uring_lock to make progress. If we hold it here across the drain
10625 * wait, then we can deadlock. It's safe to drop the mutex here, since
10626 * no new references will come in after we've killed the percpu ref.
10628 mutex_unlock(&ctx->uring_lock);
10630 ret = wait_for_completion_interruptible(&ctx->ref_comp);
10633 ret = io_run_task_work_sig();
10634 } while (ret >= 0);
10635 mutex_lock(&ctx->uring_lock);
10638 io_refs_resurrect(&ctx->refs, &ctx->ref_comp);
10642 static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
10643 void __user *arg, unsigned nr_args)
10644 __releases(ctx->uring_lock)
10645 __acquires(ctx->uring_lock)
10650 * We're inside the ring mutex, if the ref is already dying, then
10651 * someone else killed the ctx or is already going through
10652 * io_uring_register().
10654 if (percpu_ref_is_dying(&ctx->refs))
10657 if (ctx->restricted) {
10658 if (opcode >= IORING_REGISTER_LAST)
10660 opcode = array_index_nospec(opcode, IORING_REGISTER_LAST);
10661 if (!test_bit(opcode, ctx->restrictions.register_op))
10665 if (io_register_op_must_quiesce(opcode)) {
10666 ret = io_ctx_quiesce(ctx);
10672 case IORING_REGISTER_BUFFERS:
10673 ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL);
10675 case IORING_UNREGISTER_BUFFERS:
10677 if (arg || nr_args)
10679 ret = io_sqe_buffers_unregister(ctx);
10681 case IORING_REGISTER_FILES:
10682 ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
10684 case IORING_UNREGISTER_FILES:
10686 if (arg || nr_args)
10688 ret = io_sqe_files_unregister(ctx);
10690 case IORING_REGISTER_FILES_UPDATE:
10691 ret = io_register_files_update(ctx, arg, nr_args);
10693 case IORING_REGISTER_EVENTFD:
10694 case IORING_REGISTER_EVENTFD_ASYNC:
10698 ret = io_eventfd_register(ctx, arg);
10701 if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
10702 ctx->eventfd_async = 1;
10704 ctx->eventfd_async = 0;
10706 case IORING_UNREGISTER_EVENTFD:
10708 if (arg || nr_args)
10710 ret = io_eventfd_unregister(ctx);
10712 case IORING_REGISTER_PROBE:
10714 if (!arg || nr_args > 256)
10716 ret = io_probe(ctx, arg, nr_args);
10718 case IORING_REGISTER_PERSONALITY:
10720 if (arg || nr_args)
10722 ret = io_register_personality(ctx);
10724 case IORING_UNREGISTER_PERSONALITY:
10728 ret = io_unregister_personality(ctx, nr_args);
10730 case IORING_REGISTER_ENABLE_RINGS:
10732 if (arg || nr_args)
10734 ret = io_register_enable_rings(ctx);
10736 case IORING_REGISTER_RESTRICTIONS:
10737 ret = io_register_restrictions(ctx, arg, nr_args);
10739 case IORING_REGISTER_FILES2:
10740 ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE);
10742 case IORING_REGISTER_FILES_UPDATE2:
10743 ret = io_register_rsrc_update(ctx, arg, nr_args,
10746 case IORING_REGISTER_BUFFERS2:
10747 ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER);
10749 case IORING_REGISTER_BUFFERS_UPDATE:
10750 ret = io_register_rsrc_update(ctx, arg, nr_args,
10751 IORING_RSRC_BUFFER);
10753 case IORING_REGISTER_IOWQ_AFF:
10755 if (!arg || !nr_args)
10757 ret = io_register_iowq_aff(ctx, arg, nr_args);
10759 case IORING_UNREGISTER_IOWQ_AFF:
10761 if (arg || nr_args)
10763 ret = io_unregister_iowq_aff(ctx);
10765 case IORING_REGISTER_IOWQ_MAX_WORKERS:
10767 if (!arg || nr_args != 2)
10769 ret = io_register_iowq_max_workers(ctx, arg);
10776 if (io_register_op_must_quiesce(opcode)) {
10777 /* bring the ctx back to life */
10778 percpu_ref_reinit(&ctx->refs);
10779 reinit_completion(&ctx->ref_comp);
10784 SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
10785 void __user *, arg, unsigned int, nr_args)
10787 struct io_ring_ctx *ctx;
10796 if (f.file->f_op != &io_uring_fops)
10799 ctx = f.file->private_data;
10801 io_run_task_work();
10803 mutex_lock(&ctx->uring_lock);
10804 ret = __io_uring_register(ctx, opcode, arg, nr_args);
10805 mutex_unlock(&ctx->uring_lock);
10806 trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
10807 ctx->cq_ev_fd != NULL, ret);
10813 static int __init io_uring_init(void)
10815 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
10816 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
10817 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
10820 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
10821 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
10822 BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
10823 BUILD_BUG_SQE_ELEM(0, __u8, opcode);
10824 BUILD_BUG_SQE_ELEM(1, __u8, flags);
10825 BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
10826 BUILD_BUG_SQE_ELEM(4, __s32, fd);
10827 BUILD_BUG_SQE_ELEM(8, __u64, off);
10828 BUILD_BUG_SQE_ELEM(8, __u64, addr2);
10829 BUILD_BUG_SQE_ELEM(16, __u64, addr);
10830 BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
10831 BUILD_BUG_SQE_ELEM(24, __u32, len);
10832 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
10833 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
10834 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
10835 BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
10836 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
10837 BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
10838 BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
10839 BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
10840 BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
10841 BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
10842 BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
10843 BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
10844 BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
10845 BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
10846 BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
10847 BUILD_BUG_SQE_ELEM(32, __u64, user_data);
10848 BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
10849 BUILD_BUG_SQE_ELEM(40, __u16, buf_group);
10850 BUILD_BUG_SQE_ELEM(42, __u16, personality);
10851 BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
10852 BUILD_BUG_SQE_ELEM(44, __u32, file_index);
10854 BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=
10855 sizeof(struct io_uring_rsrc_update));
10856 BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) >
10857 sizeof(struct io_uring_rsrc_update2));
10859 /* ->buf_index is u16 */
10860 BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16));
10862 /* should fit into one byte */
10863 BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));
10865 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
10866 BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int));
10868 req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
10872 __initcall(io_uring_init);