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/blk-mq.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/audit.h>
82 #include <linux/security.h>
83 #include <linux/xattr.h>
85 #define CREATE_TRACE_POINTS
86 #include <trace/events/io_uring.h>
88 #include <uapi/linux/io_uring.h>
93 #define IORING_MAX_ENTRIES 32768
94 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
95 #define IORING_SQPOLL_CAP_ENTRIES_VALUE 8
98 #define IORING_MAX_FIXED_FILES (1U << 20)
99 #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
100 IORING_REGISTER_LAST + IORING_OP_LAST)
102 #define IO_RSRC_TAG_TABLE_SHIFT (PAGE_SHIFT - 3)
103 #define IO_RSRC_TAG_TABLE_MAX (1U << IO_RSRC_TAG_TABLE_SHIFT)
104 #define IO_RSRC_TAG_TABLE_MASK (IO_RSRC_TAG_TABLE_MAX - 1)
106 #define IORING_MAX_REG_BUFFERS (1U << 14)
108 #define SQE_COMMON_FLAGS (IOSQE_FIXED_FILE | IOSQE_IO_LINK | \
109 IOSQE_IO_HARDLINK | IOSQE_ASYNC)
111 #define SQE_VALID_FLAGS (SQE_COMMON_FLAGS | IOSQE_BUFFER_SELECT | \
112 IOSQE_IO_DRAIN | IOSQE_CQE_SKIP_SUCCESS)
114 #define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
115 REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS | \
118 #define IO_REQ_CLEAN_SLOW_FLAGS (REQ_F_REFCOUNT | REQ_F_LINK | REQ_F_HARDLINK |\
121 #define IO_APOLL_MULTI_POLLED (REQ_F_APOLL_MULTISHOT | REQ_F_POLLED)
123 #define IO_TCTX_REFS_CACHE_NR (1U << 10)
126 u32 head ____cacheline_aligned_in_smp;
127 u32 tail ____cacheline_aligned_in_smp;
131 * This data is shared with the application through the mmap at offsets
132 * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
134 * The offsets to the member fields are published through struct
135 * io_sqring_offsets when calling io_uring_setup.
139 * Head and tail offsets into the ring; the offsets need to be
140 * masked to get valid indices.
142 * The kernel controls head of the sq ring and the tail of the cq ring,
143 * and the application controls tail of the sq ring and the head of the
146 struct io_uring sq, cq;
148 * Bitmasks to apply to head and tail offsets (constant, equals
151 u32 sq_ring_mask, cq_ring_mask;
152 /* Ring sizes (constant, power of 2) */
153 u32 sq_ring_entries, cq_ring_entries;
155 * Number of invalid entries dropped by the kernel due to
156 * invalid index stored in array
158 * Written by the kernel, shouldn't be modified by the
159 * application (i.e. get number of "new events" by comparing to
162 * After a new SQ head value was read by the application this
163 * counter includes all submissions that were dropped reaching
164 * the new SQ head (and possibly more).
170 * Written by the kernel, shouldn't be modified by the
173 * The application needs a full memory barrier before checking
174 * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
180 * Written by the application, shouldn't be modified by the
185 * Number of completion events lost because the queue was full;
186 * this should be avoided by the application by making sure
187 * there are not more requests pending than there is space in
188 * the completion queue.
190 * Written by the kernel, shouldn't be modified by the
191 * application (i.e. get number of "new events" by comparing to
194 * As completion events come in out of order this counter is not
195 * ordered with any other data.
199 * Ring buffer of completion events.
201 * The kernel writes completion events fresh every time they are
202 * produced, so the application is allowed to modify pending
205 struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp;
208 struct io_mapped_ubuf {
211 unsigned int nr_bvecs;
212 unsigned long acct_pages;
213 struct bio_vec bvec[];
218 struct io_overflow_cqe {
219 struct list_head list;
220 struct io_uring_cqe cqe;
224 * FFS_SCM is only available on 64-bit archs, for 32-bit we just define it as 0
225 * and define IO_URING_SCM_ALL. For this case, we use SCM for all files as we
226 * can't safely always dereference the file when the task has exited and ring
227 * cleanup is done. If a file is tracked and part of SCM, then unix gc on
228 * process exit may reap it before __io_sqe_files_unregister() is run.
230 #define FFS_NOWAIT 0x1UL
231 #define FFS_ISREG 0x2UL
232 #if defined(CONFIG_64BIT)
233 #define FFS_SCM 0x4UL
235 #define IO_URING_SCM_ALL
236 #define FFS_SCM 0x0UL
238 #define FFS_MASK ~(FFS_NOWAIT|FFS_ISREG|FFS_SCM)
240 struct io_fixed_file {
241 /* file * with additional FFS_* flags */
242 unsigned long file_ptr;
246 struct list_head list;
251 struct io_mapped_ubuf *buf;
255 struct io_file_table {
256 struct io_fixed_file *files;
257 unsigned long *bitmap;
258 unsigned int alloc_hint;
261 struct io_rsrc_node {
262 struct percpu_ref refs;
263 struct list_head node;
264 struct list_head rsrc_list;
265 struct io_rsrc_data *rsrc_data;
266 struct llist_node llist;
270 typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
272 struct io_rsrc_data {
273 struct io_ring_ctx *ctx;
279 struct completion done;
283 #define IO_BUFFER_LIST_BUF_PER_PAGE (PAGE_SIZE / sizeof(struct io_uring_buf))
284 struct io_buffer_list {
286 * If ->buf_nr_pages is set, then buf_pages/buf_ring are used. If not,
287 * then these are classic provided buffers and ->buf_list is used.
290 struct list_head buf_list;
292 struct page **buf_pages;
293 struct io_uring_buf_ring *buf_ring;
298 /* below is for ring provided buffers */
306 struct list_head list;
313 struct io_restriction {
314 DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
315 DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
316 u8 sqe_flags_allowed;
317 u8 sqe_flags_required;
322 IO_SQ_THREAD_SHOULD_STOP = 0,
323 IO_SQ_THREAD_SHOULD_PARK,
328 atomic_t park_pending;
331 /* ctx's that are using this sqd */
332 struct list_head ctx_list;
334 struct task_struct *thread;
335 struct wait_queue_head wait;
337 unsigned sq_thread_idle;
343 struct completion exited;
346 #define IO_COMPL_BATCH 32
347 #define IO_REQ_CACHE_SIZE 32
348 #define IO_REQ_ALLOC_BATCH 8
350 struct io_submit_link {
351 struct io_kiocb *head;
352 struct io_kiocb *last;
355 struct io_submit_state {
356 /* inline/task_work completion list, under ->uring_lock */
357 struct io_wq_work_node free_list;
358 /* batch completion logic */
359 struct io_wq_work_list compl_reqs;
360 struct io_submit_link link;
365 unsigned short submit_nr;
366 struct blk_plug plug;
370 struct eventfd_ctx *cq_ev_fd;
371 unsigned int eventfd_async: 1;
375 #define BGID_ARRAY 64
378 /* const or read-mostly hot data */
380 struct percpu_ref refs;
382 struct io_rings *rings;
384 enum task_work_notify_mode notify_method;
385 unsigned int compat: 1;
386 unsigned int drain_next: 1;
387 unsigned int restricted: 1;
388 unsigned int off_timeout_used: 1;
389 unsigned int drain_active: 1;
390 unsigned int drain_disabled: 1;
391 unsigned int has_evfd: 1;
392 unsigned int syscall_iopoll: 1;
393 } ____cacheline_aligned_in_smp;
395 /* submission data */
397 struct mutex uring_lock;
400 * Ring buffer of indices into array of io_uring_sqe, which is
401 * mmapped by the application using the IORING_OFF_SQES offset.
403 * This indirection could e.g. be used to assign fixed
404 * io_uring_sqe entries to operations and only submit them to
405 * the queue when needed.
407 * The kernel modifies neither the indices array nor the entries
411 struct io_uring_sqe *sq_sqes;
412 unsigned cached_sq_head;
414 struct list_head defer_list;
417 * Fixed resources fast path, should be accessed only under
418 * uring_lock, and updated through io_uring_register(2)
420 struct io_rsrc_node *rsrc_node;
421 int rsrc_cached_refs;
423 struct io_file_table file_table;
424 unsigned nr_user_files;
425 unsigned nr_user_bufs;
426 struct io_mapped_ubuf **user_bufs;
428 struct io_submit_state submit_state;
430 struct io_buffer_list *io_bl;
431 struct xarray io_bl_xa;
432 struct list_head io_buffers_cache;
434 struct list_head timeout_list;
435 struct list_head ltimeout_list;
436 struct list_head cq_overflow_list;
437 struct list_head apoll_cache;
438 struct xarray personalities;
440 unsigned sq_thread_idle;
441 } ____cacheline_aligned_in_smp;
443 /* IRQ completion list, under ->completion_lock */
444 struct io_wq_work_list locked_free_list;
445 unsigned int locked_free_nr;
447 const struct cred *sq_creds; /* cred used for __io_sq_thread() */
448 struct io_sq_data *sq_data; /* if using sq thread polling */
450 struct wait_queue_head sqo_sq_wait;
451 struct list_head sqd_list;
453 unsigned long check_cq;
457 * We cache a range of free CQEs we can use, once exhausted it
458 * should go through a slower range setup, see __io_get_cqe()
460 struct io_uring_cqe *cqe_cached;
461 struct io_uring_cqe *cqe_sentinel;
463 unsigned cached_cq_tail;
465 struct io_ev_fd __rcu *io_ev_fd;
466 struct wait_queue_head cq_wait;
468 atomic_t cq_timeouts;
469 unsigned cq_last_tm_flush;
470 } ____cacheline_aligned_in_smp;
473 spinlock_t completion_lock;
475 spinlock_t timeout_lock;
478 * ->iopoll_list is protected by the ctx->uring_lock for
479 * io_uring instances that don't use IORING_SETUP_SQPOLL.
480 * For SQPOLL, only the single threaded io_sq_thread() will
481 * manipulate the list, hence no extra locking is needed there.
483 struct io_wq_work_list iopoll_list;
484 struct hlist_head *cancel_hash;
485 unsigned cancel_hash_bits;
486 bool poll_multi_queue;
488 struct list_head io_buffers_comp;
489 } ____cacheline_aligned_in_smp;
491 struct io_restriction restrictions;
493 /* slow path rsrc auxilary data, used by update/register */
495 struct io_rsrc_node *rsrc_backup_node;
496 struct io_mapped_ubuf *dummy_ubuf;
497 struct io_rsrc_data *file_data;
498 struct io_rsrc_data *buf_data;
500 struct delayed_work rsrc_put_work;
501 struct llist_head rsrc_put_llist;
502 struct list_head rsrc_ref_list;
503 spinlock_t rsrc_ref_lock;
505 struct list_head io_buffers_pages;
508 /* Keep this last, we don't need it for the fast path */
510 #if defined(CONFIG_UNIX)
511 struct socket *ring_sock;
513 /* hashed buffered write serialization */
514 struct io_wq_hash *hash_map;
516 /* Only used for accounting purposes */
517 struct user_struct *user;
518 struct mm_struct *mm_account;
520 /* ctx exit and cancelation */
521 struct llist_head fallback_llist;
522 struct delayed_work fallback_work;
523 struct work_struct exit_work;
524 struct list_head tctx_list;
525 struct completion ref_comp;
527 bool iowq_limits_set;
532 * Arbitrary limit, can be raised if need be
534 #define IO_RINGFD_REG_MAX 16
536 struct io_uring_task {
537 /* submission side */
540 struct wait_queue_head wait;
541 const struct io_ring_ctx *last;
543 struct percpu_counter inflight;
544 atomic_t inflight_tracked;
547 spinlock_t task_lock;
548 struct io_wq_work_list task_list;
549 struct io_wq_work_list prio_task_list;
550 struct callback_head task_work;
551 struct file **registered_rings;
556 * First field must be the file pointer in all the
557 * iocb unions! See also 'struct kiocb' in <linux/fs.h>
559 struct io_poll_iocb {
561 struct wait_queue_head *head;
563 struct wait_queue_entry wait;
566 struct io_poll_update {
572 bool update_user_data;
581 struct io_timeout_data {
582 struct io_kiocb *req;
583 struct hrtimer timer;
584 struct timespec64 ts;
585 enum hrtimer_mode mode;
591 struct sockaddr __user *addr;
592 int __user *addr_len;
595 unsigned long nofile;
605 unsigned long nofile;
627 struct list_head list;
628 /* head of the link, used by linked timeouts only */
629 struct io_kiocb *head;
630 /* for linked completions */
631 struct io_kiocb *prev;
634 struct io_timeout_rem {
639 struct timespec64 ts;
645 /* NOTE: kiocb has the file as the first member, so don't do it here */
654 struct sockaddr __user *addr;
661 struct compat_msghdr __user *umsg_compat;
662 struct user_msghdr __user *umsg;
675 struct filename *filename;
677 unsigned long nofile;
680 struct io_rsrc_update {
706 struct epoll_event event;
710 struct file *file_out;
718 struct io_provide_buf {
732 struct filename *filename;
733 struct statx __user *buffer;
745 struct filename *oldpath;
746 struct filename *newpath;
754 struct filename *filename;
761 struct filename *filename;
767 struct filename *oldpath;
768 struct filename *newpath;
775 struct filename *oldpath;
776 struct filename *newpath;
786 struct io_async_connect {
787 struct sockaddr_storage address;
790 struct io_async_msghdr {
791 struct iovec fast_iov[UIO_FASTIOV];
792 /* points to an allocated iov, if NULL we use fast_iov instead */
793 struct iovec *free_iov;
794 struct sockaddr __user *uaddr;
796 struct sockaddr_storage addr;
800 struct iov_iter iter;
801 struct iov_iter_state iter_state;
802 struct iovec fast_iov[UIO_FASTIOV];
806 struct io_rw_state s;
807 const struct iovec *free_iovec;
809 struct wait_page_queue wpq;
814 struct xattr_ctx ctx;
815 struct filename *filename;
819 REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
820 REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
821 REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
822 REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
823 REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
824 REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
825 REQ_F_CQE_SKIP_BIT = IOSQE_CQE_SKIP_SUCCESS_BIT,
827 /* first byte is taken by user flags, shift it to not overlap */
832 REQ_F_LINK_TIMEOUT_BIT,
833 REQ_F_NEED_CLEANUP_BIT,
835 REQ_F_BUFFER_SELECTED_BIT,
836 REQ_F_BUFFER_RING_BIT,
837 REQ_F_COMPLETE_INLINE_BIT,
841 REQ_F_ARM_LTIMEOUT_BIT,
842 REQ_F_ASYNC_DATA_BIT,
843 REQ_F_SKIP_LINK_CQES_BIT,
844 REQ_F_SINGLE_POLL_BIT,
845 REQ_F_DOUBLE_POLL_BIT,
846 REQ_F_PARTIAL_IO_BIT,
847 REQ_F_CQE32_INIT_BIT,
848 REQ_F_APOLL_MULTISHOT_BIT,
849 /* keep async read/write and isreg together and in order */
850 REQ_F_SUPPORT_NOWAIT_BIT,
853 /* not a real bit, just to check we're not overflowing the space */
859 REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
860 /* drain existing IO first */
861 REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
863 REQ_F_LINK = BIT(REQ_F_LINK_BIT),
864 /* doesn't sever on completion < 0 */
865 REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
867 REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
868 /* IOSQE_BUFFER_SELECT */
869 REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
870 /* IOSQE_CQE_SKIP_SUCCESS */
871 REQ_F_CQE_SKIP = BIT(REQ_F_CQE_SKIP_BIT),
873 /* fail rest of links */
874 REQ_F_FAIL = BIT(REQ_F_FAIL_BIT),
875 /* on inflight list, should be cancelled and waited on exit reliably */
876 REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
877 /* read/write uses file position */
878 REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
879 /* must not punt to workers */
880 REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
881 /* has or had linked timeout */
882 REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
884 REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
885 /* already went through poll handler */
886 REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
887 /* buffer already selected */
888 REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
889 /* buffer selected from ring, needs commit */
890 REQ_F_BUFFER_RING = BIT(REQ_F_BUFFER_RING_BIT),
891 /* completion is deferred through io_comp_state */
892 REQ_F_COMPLETE_INLINE = BIT(REQ_F_COMPLETE_INLINE_BIT),
893 /* caller should reissue async */
894 REQ_F_REISSUE = BIT(REQ_F_REISSUE_BIT),
895 /* supports async reads/writes */
896 REQ_F_SUPPORT_NOWAIT = BIT(REQ_F_SUPPORT_NOWAIT_BIT),
898 REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
899 /* has creds assigned */
900 REQ_F_CREDS = BIT(REQ_F_CREDS_BIT),
901 /* skip refcounting if not set */
902 REQ_F_REFCOUNT = BIT(REQ_F_REFCOUNT_BIT),
903 /* there is a linked timeout that has to be armed */
904 REQ_F_ARM_LTIMEOUT = BIT(REQ_F_ARM_LTIMEOUT_BIT),
905 /* ->async_data allocated */
906 REQ_F_ASYNC_DATA = BIT(REQ_F_ASYNC_DATA_BIT),
907 /* don't post CQEs while failing linked requests */
908 REQ_F_SKIP_LINK_CQES = BIT(REQ_F_SKIP_LINK_CQES_BIT),
909 /* single poll may be active */
910 REQ_F_SINGLE_POLL = BIT(REQ_F_SINGLE_POLL_BIT),
911 /* double poll may active */
912 REQ_F_DOUBLE_POLL = BIT(REQ_F_DOUBLE_POLL_BIT),
913 /* request has already done partial IO */
914 REQ_F_PARTIAL_IO = BIT(REQ_F_PARTIAL_IO_BIT),
915 /* fast poll multishot mode */
916 REQ_F_APOLL_MULTISHOT = BIT(REQ_F_APOLL_MULTISHOT_BIT),
917 /* ->extra1 and ->extra2 are initialised */
918 REQ_F_CQE32_INIT = BIT(REQ_F_CQE32_INIT_BIT),
922 struct io_poll_iocb poll;
923 struct io_poll_iocb *double_poll;
926 typedef void (*io_req_tw_func_t)(struct io_kiocb *req, bool *locked);
928 struct io_task_work {
930 struct io_wq_work_node node;
931 struct llist_node fallback_node;
933 io_req_tw_func_t func;
937 IORING_RSRC_FILE = 0,
938 IORING_RSRC_BUFFER = 1,
944 /* fd initially, then cflags for completion */
952 IO_CHECK_CQ_OVERFLOW_BIT,
953 IO_CHECK_CQ_DROPPED_BIT,
957 * NOTE! Each of the iocb union members has the file pointer
958 * as the first entry in their struct definition. So you can
959 * access the file pointer through any of the sub-structs,
960 * or directly as just 'file' in this struct.
966 struct io_poll_iocb poll;
967 struct io_poll_update poll_update;
968 struct io_accept accept;
970 struct io_cancel cancel;
971 struct io_timeout timeout;
972 struct io_timeout_rem timeout_rem;
973 struct io_connect connect;
974 struct io_sr_msg sr_msg;
976 struct io_close close;
977 struct io_rsrc_update rsrc_update;
978 struct io_fadvise fadvise;
979 struct io_madvise madvise;
980 struct io_epoll epoll;
981 struct io_splice splice;
982 struct io_provide_buf pbuf;
983 struct io_statx statx;
984 struct io_shutdown shutdown;
985 struct io_rename rename;
986 struct io_unlink unlink;
987 struct io_mkdir mkdir;
988 struct io_symlink symlink;
989 struct io_hardlink hardlink;
991 struct io_xattr xattr;
992 struct io_socket sock;
993 struct io_uring_cmd uring_cmd;
997 /* polled IO has completed */
1000 * Can be either a fixed buffer index, or used with provided buffers.
1001 * For the latter, before issue it points to the buffer group ID,
1002 * and after selection it points to the buffer ID itself.
1009 struct io_ring_ctx *ctx;
1010 struct task_struct *task;
1012 struct io_rsrc_node *rsrc_node;
1015 /* store used ubuf, so we can prevent reloading */
1016 struct io_mapped_ubuf *imu;
1018 /* stores selected buf, valid IFF REQ_F_BUFFER_SELECTED is set */
1019 struct io_buffer *kbuf;
1022 * stores buffer ID for ring provided buffers, valid IFF
1023 * REQ_F_BUFFER_RING is set.
1025 struct io_buffer_list *buf_list;
1029 /* used by request caches, completion batching and iopoll */
1030 struct io_wq_work_node comp_list;
1031 /* cache ->apoll->events */
1032 __poll_t apoll_events;
1036 struct io_task_work io_task_work;
1037 /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
1039 struct hlist_node hash_node;
1045 /* internal polling, see IORING_FEAT_FAST_POLL */
1046 struct async_poll *apoll;
1047 /* opcode allocated if it needs to store data for async defer */
1049 /* linked requests, IFF REQ_F_HARDLINK or REQ_F_LINK are set */
1050 struct io_kiocb *link;
1051 /* custom credentials, valid IFF REQ_F_CREDS is set */
1052 const struct cred *creds;
1053 struct io_wq_work work;
1056 struct io_tctx_node {
1057 struct list_head ctx_node;
1058 struct task_struct *task;
1059 struct io_ring_ctx *ctx;
1062 struct io_defer_entry {
1063 struct list_head list;
1064 struct io_kiocb *req;
1068 struct io_cancel_data {
1069 struct io_ring_ctx *ctx;
1079 * The URING_CMD payload starts at 'cmd' in the first sqe, and continues into
1080 * the following sqe if SQE128 is used.
1082 #define uring_cmd_pdu_size(is_sqe128) \
1083 ((1 + !!(is_sqe128)) * sizeof(struct io_uring_sqe) - \
1084 offsetof(struct io_uring_sqe, cmd))
1087 /* needs req->file assigned */
1088 unsigned needs_file : 1;
1089 /* should block plug */
1091 /* hash wq insertion if file is a regular file */
1092 unsigned hash_reg_file : 1;
1093 /* unbound wq insertion if file is a non-regular file */
1094 unsigned unbound_nonreg_file : 1;
1095 /* set if opcode supports polled "wait" */
1096 unsigned pollin : 1;
1097 unsigned pollout : 1;
1098 unsigned poll_exclusive : 1;
1099 /* op supports buffer selection */
1100 unsigned buffer_select : 1;
1101 /* do prep async if is going to be punted */
1102 unsigned needs_async_setup : 1;
1103 /* opcode is not supported by this kernel */
1104 unsigned not_supported : 1;
1106 unsigned audit_skip : 1;
1107 /* supports ioprio */
1108 unsigned ioprio : 1;
1109 /* supports iopoll */
1110 unsigned iopoll : 1;
1111 /* size of async data needed, if any */
1112 unsigned short async_size;
1115 static const struct io_op_def io_op_defs[] = {
1120 [IORING_OP_READV] = {
1122 .unbound_nonreg_file = 1,
1125 .needs_async_setup = 1,
1130 .async_size = sizeof(struct io_async_rw),
1132 [IORING_OP_WRITEV] = {
1135 .unbound_nonreg_file = 1,
1137 .needs_async_setup = 1,
1142 .async_size = sizeof(struct io_async_rw),
1144 [IORING_OP_FSYNC] = {
1148 [IORING_OP_READ_FIXED] = {
1150 .unbound_nonreg_file = 1,
1156 .async_size = sizeof(struct io_async_rw),
1158 [IORING_OP_WRITE_FIXED] = {
1161 .unbound_nonreg_file = 1,
1167 .async_size = sizeof(struct io_async_rw),
1169 [IORING_OP_POLL_ADD] = {
1171 .unbound_nonreg_file = 1,
1174 [IORING_OP_POLL_REMOVE] = {
1177 [IORING_OP_SYNC_FILE_RANGE] = {
1181 [IORING_OP_SENDMSG] = {
1183 .unbound_nonreg_file = 1,
1185 .needs_async_setup = 1,
1186 .async_size = sizeof(struct io_async_msghdr),
1188 [IORING_OP_RECVMSG] = {
1190 .unbound_nonreg_file = 1,
1193 .needs_async_setup = 1,
1194 .async_size = sizeof(struct io_async_msghdr),
1196 [IORING_OP_TIMEOUT] = {
1198 .async_size = sizeof(struct io_timeout_data),
1200 [IORING_OP_TIMEOUT_REMOVE] = {
1201 /* used by timeout updates' prep() */
1204 [IORING_OP_ACCEPT] = {
1206 .unbound_nonreg_file = 1,
1208 .poll_exclusive = 1,
1209 .ioprio = 1, /* used for flags */
1211 [IORING_OP_ASYNC_CANCEL] = {
1214 [IORING_OP_LINK_TIMEOUT] = {
1216 .async_size = sizeof(struct io_timeout_data),
1218 [IORING_OP_CONNECT] = {
1220 .unbound_nonreg_file = 1,
1222 .needs_async_setup = 1,
1223 .async_size = sizeof(struct io_async_connect),
1225 [IORING_OP_FALLOCATE] = {
1228 [IORING_OP_OPENAT] = {},
1229 [IORING_OP_CLOSE] = {},
1230 [IORING_OP_FILES_UPDATE] = {
1234 [IORING_OP_STATX] = {
1237 [IORING_OP_READ] = {
1239 .unbound_nonreg_file = 1,
1246 .async_size = sizeof(struct io_async_rw),
1248 [IORING_OP_WRITE] = {
1251 .unbound_nonreg_file = 1,
1257 .async_size = sizeof(struct io_async_rw),
1259 [IORING_OP_FADVISE] = {
1263 [IORING_OP_MADVISE] = {},
1264 [IORING_OP_SEND] = {
1266 .unbound_nonreg_file = 1,
1270 [IORING_OP_RECV] = {
1272 .unbound_nonreg_file = 1,
1277 [IORING_OP_OPENAT2] = {
1279 [IORING_OP_EPOLL_CTL] = {
1280 .unbound_nonreg_file = 1,
1283 [IORING_OP_SPLICE] = {
1286 .unbound_nonreg_file = 1,
1289 [IORING_OP_PROVIDE_BUFFERS] = {
1293 [IORING_OP_REMOVE_BUFFERS] = {
1300 .unbound_nonreg_file = 1,
1303 [IORING_OP_SHUTDOWN] = {
1306 [IORING_OP_RENAMEAT] = {},
1307 [IORING_OP_UNLINKAT] = {},
1308 [IORING_OP_MKDIRAT] = {},
1309 [IORING_OP_SYMLINKAT] = {},
1310 [IORING_OP_LINKAT] = {},
1311 [IORING_OP_MSG_RING] = {
1315 [IORING_OP_FSETXATTR] = {
1318 [IORING_OP_SETXATTR] = {},
1319 [IORING_OP_FGETXATTR] = {
1322 [IORING_OP_GETXATTR] = {},
1323 [IORING_OP_SOCKET] = {
1326 [IORING_OP_URING_CMD] = {
1329 .needs_async_setup = 1,
1330 .async_size = uring_cmd_pdu_size(1),
1334 /* requests with any of those set should undergo io_disarm_next() */
1335 #define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
1336 #define IO_REQ_LINK_FLAGS (REQ_F_LINK | REQ_F_HARDLINK)
1338 static bool io_disarm_next(struct io_kiocb *req);
1339 static void io_uring_del_tctx_node(unsigned long index);
1340 static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
1341 struct task_struct *task,
1343 static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
1345 static void __io_req_complete_post(struct io_kiocb *req, s32 res, u32 cflags);
1346 static void io_dismantle_req(struct io_kiocb *req);
1347 static void io_queue_linked_timeout(struct io_kiocb *req);
1348 static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
1349 struct io_uring_rsrc_update2 *up,
1351 static void io_clean_op(struct io_kiocb *req);
1352 static inline struct file *io_file_get_fixed(struct io_kiocb *req, int fd,
1353 unsigned issue_flags);
1354 static struct file *io_file_get_normal(struct io_kiocb *req, int fd);
1355 static void io_queue_sqe(struct io_kiocb *req);
1356 static void io_rsrc_put_work(struct work_struct *work);
1358 static void io_req_task_queue(struct io_kiocb *req);
1359 static void __io_submit_flush_completions(struct io_ring_ctx *ctx);
1360 static int io_req_prep_async(struct io_kiocb *req);
1362 static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
1363 unsigned int issue_flags, u32 slot_index);
1364 static int __io_close_fixed(struct io_kiocb *req, unsigned int issue_flags,
1365 unsigned int offset);
1366 static inline int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags);
1368 static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer);
1369 static void io_eventfd_signal(struct io_ring_ctx *ctx);
1370 static void io_req_tw_post_queue(struct io_kiocb *req, s32 res, u32 cflags);
1372 static struct kmem_cache *req_cachep;
1374 static const struct file_operations io_uring_fops;
1376 const char *io_uring_get_opcode(u8 opcode)
1378 switch ((enum io_uring_op)opcode) {
1381 case IORING_OP_READV:
1383 case IORING_OP_WRITEV:
1385 case IORING_OP_FSYNC:
1387 case IORING_OP_READ_FIXED:
1388 return "READ_FIXED";
1389 case IORING_OP_WRITE_FIXED:
1390 return "WRITE_FIXED";
1391 case IORING_OP_POLL_ADD:
1393 case IORING_OP_POLL_REMOVE:
1394 return "POLL_REMOVE";
1395 case IORING_OP_SYNC_FILE_RANGE:
1396 return "SYNC_FILE_RANGE";
1397 case IORING_OP_SENDMSG:
1399 case IORING_OP_RECVMSG:
1401 case IORING_OP_TIMEOUT:
1403 case IORING_OP_TIMEOUT_REMOVE:
1404 return "TIMEOUT_REMOVE";
1405 case IORING_OP_ACCEPT:
1407 case IORING_OP_ASYNC_CANCEL:
1408 return "ASYNC_CANCEL";
1409 case IORING_OP_LINK_TIMEOUT:
1410 return "LINK_TIMEOUT";
1411 case IORING_OP_CONNECT:
1413 case IORING_OP_FALLOCATE:
1415 case IORING_OP_OPENAT:
1417 case IORING_OP_CLOSE:
1419 case IORING_OP_FILES_UPDATE:
1420 return "FILES_UPDATE";
1421 case IORING_OP_STATX:
1423 case IORING_OP_READ:
1425 case IORING_OP_WRITE:
1427 case IORING_OP_FADVISE:
1429 case IORING_OP_MADVISE:
1431 case IORING_OP_SEND:
1433 case IORING_OP_RECV:
1435 case IORING_OP_OPENAT2:
1437 case IORING_OP_EPOLL_CTL:
1439 case IORING_OP_SPLICE:
1441 case IORING_OP_PROVIDE_BUFFERS:
1442 return "PROVIDE_BUFFERS";
1443 case IORING_OP_REMOVE_BUFFERS:
1444 return "REMOVE_BUFFERS";
1447 case IORING_OP_SHUTDOWN:
1449 case IORING_OP_RENAMEAT:
1451 case IORING_OP_UNLINKAT:
1453 case IORING_OP_MKDIRAT:
1455 case IORING_OP_SYMLINKAT:
1457 case IORING_OP_LINKAT:
1459 case IORING_OP_MSG_RING:
1461 case IORING_OP_FSETXATTR:
1463 case IORING_OP_SETXATTR:
1465 case IORING_OP_FGETXATTR:
1467 case IORING_OP_GETXATTR:
1469 case IORING_OP_SOCKET:
1471 case IORING_OP_URING_CMD:
1473 case IORING_OP_LAST:
1479 struct sock *io_uring_get_socket(struct file *file)
1481 #if defined(CONFIG_UNIX)
1482 if (file->f_op == &io_uring_fops) {
1483 struct io_ring_ctx *ctx = file->private_data;
1485 return ctx->ring_sock->sk;
1490 EXPORT_SYMBOL(io_uring_get_socket);
1492 #if defined(CONFIG_UNIX)
1493 static inline bool io_file_need_scm(struct file *filp)
1495 #if defined(IO_URING_SCM_ALL)
1498 return !!unix_get_socket(filp);
1502 static inline bool io_file_need_scm(struct file *filp)
1508 static void io_ring_submit_unlock(struct io_ring_ctx *ctx, unsigned issue_flags)
1510 lockdep_assert_held(&ctx->uring_lock);
1511 if (issue_flags & IO_URING_F_UNLOCKED)
1512 mutex_unlock(&ctx->uring_lock);
1515 static void io_ring_submit_lock(struct io_ring_ctx *ctx, unsigned issue_flags)
1518 * "Normal" inline submissions always hold the uring_lock, since we
1519 * grab it from the system call. Same is true for the SQPOLL offload.
1520 * The only exception is when we've detached the request and issue it
1521 * from an async worker thread, grab the lock for that case.
1523 if (issue_flags & IO_URING_F_UNLOCKED)
1524 mutex_lock(&ctx->uring_lock);
1525 lockdep_assert_held(&ctx->uring_lock);
1528 static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked)
1531 mutex_lock(&ctx->uring_lock);
1536 #define io_for_each_link(pos, head) \
1537 for (pos = (head); pos; pos = pos->link)
1540 * Shamelessly stolen from the mm implementation of page reference checking,
1541 * see commit f958d7b528b1 for details.
1543 #define req_ref_zero_or_close_to_overflow(req) \
1544 ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
1546 static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
1548 WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
1549 return atomic_inc_not_zero(&req->refs);
1552 static inline bool req_ref_put_and_test(struct io_kiocb *req)
1554 if (likely(!(req->flags & REQ_F_REFCOUNT)))
1557 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1558 return atomic_dec_and_test(&req->refs);
1561 static inline void req_ref_get(struct io_kiocb *req)
1563 WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
1564 WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
1565 atomic_inc(&req->refs);
1568 static inline void io_submit_flush_completions(struct io_ring_ctx *ctx)
1570 if (!wq_list_empty(&ctx->submit_state.compl_reqs))
1571 __io_submit_flush_completions(ctx);
1574 static inline void __io_req_set_refcount(struct io_kiocb *req, int nr)
1576 if (!(req->flags & REQ_F_REFCOUNT)) {
1577 req->flags |= REQ_F_REFCOUNT;
1578 atomic_set(&req->refs, nr);
1582 static inline void io_req_set_refcount(struct io_kiocb *req)
1584 __io_req_set_refcount(req, 1);
1587 #define IO_RSRC_REF_BATCH 100
1589 static void io_rsrc_put_node(struct io_rsrc_node *node, int nr)
1591 percpu_ref_put_many(&node->refs, nr);
1594 static inline void io_req_put_rsrc_locked(struct io_kiocb *req,
1595 struct io_ring_ctx *ctx)
1596 __must_hold(&ctx->uring_lock)
1598 struct io_rsrc_node *node = req->rsrc_node;
1601 if (node == ctx->rsrc_node)
1602 ctx->rsrc_cached_refs++;
1604 io_rsrc_put_node(node, 1);
1608 static inline void io_req_put_rsrc(struct io_kiocb *req)
1611 io_rsrc_put_node(req->rsrc_node, 1);
1614 static __cold void io_rsrc_refs_drop(struct io_ring_ctx *ctx)
1615 __must_hold(&ctx->uring_lock)
1617 if (ctx->rsrc_cached_refs) {
1618 io_rsrc_put_node(ctx->rsrc_node, ctx->rsrc_cached_refs);
1619 ctx->rsrc_cached_refs = 0;
1623 static void io_rsrc_refs_refill(struct io_ring_ctx *ctx)
1624 __must_hold(&ctx->uring_lock)
1626 ctx->rsrc_cached_refs += IO_RSRC_REF_BATCH;
1627 percpu_ref_get_many(&ctx->rsrc_node->refs, IO_RSRC_REF_BATCH);
1630 static inline void io_req_set_rsrc_node(struct io_kiocb *req,
1631 struct io_ring_ctx *ctx,
1632 unsigned int issue_flags)
1634 if (!req->rsrc_node) {
1635 req->rsrc_node = ctx->rsrc_node;
1637 if (!(issue_flags & IO_URING_F_UNLOCKED)) {
1638 lockdep_assert_held(&ctx->uring_lock);
1639 ctx->rsrc_cached_refs--;
1640 if (unlikely(ctx->rsrc_cached_refs < 0))
1641 io_rsrc_refs_refill(ctx);
1643 percpu_ref_get(&req->rsrc_node->refs);
1648 static unsigned int __io_put_kbuf(struct io_kiocb *req, struct list_head *list)
1650 if (req->flags & REQ_F_BUFFER_RING) {
1652 req->buf_list->head++;
1653 req->flags &= ~REQ_F_BUFFER_RING;
1655 list_add(&req->kbuf->list, list);
1656 req->flags &= ~REQ_F_BUFFER_SELECTED;
1659 return IORING_CQE_F_BUFFER | (req->buf_index << IORING_CQE_BUFFER_SHIFT);
1662 static inline unsigned int io_put_kbuf_comp(struct io_kiocb *req)
1664 lockdep_assert_held(&req->ctx->completion_lock);
1666 if (!(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING)))
1668 return __io_put_kbuf(req, &req->ctx->io_buffers_comp);
1671 static inline unsigned int io_put_kbuf(struct io_kiocb *req,
1672 unsigned issue_flags)
1674 unsigned int cflags;
1676 if (!(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING)))
1680 * We can add this buffer back to two lists:
1682 * 1) The io_buffers_cache list. This one is protected by the
1683 * ctx->uring_lock. If we already hold this lock, add back to this
1684 * list as we can grab it from issue as well.
1685 * 2) The io_buffers_comp list. This one is protected by the
1686 * ctx->completion_lock.
1688 * We migrate buffers from the comp_list to the issue cache list
1691 if (req->flags & REQ_F_BUFFER_RING) {
1692 /* no buffers to recycle for this case */
1693 cflags = __io_put_kbuf(req, NULL);
1694 } else if (issue_flags & IO_URING_F_UNLOCKED) {
1695 struct io_ring_ctx *ctx = req->ctx;
1697 spin_lock(&ctx->completion_lock);
1698 cflags = __io_put_kbuf(req, &ctx->io_buffers_comp);
1699 spin_unlock(&ctx->completion_lock);
1701 lockdep_assert_held(&req->ctx->uring_lock);
1703 cflags = __io_put_kbuf(req, &req->ctx->io_buffers_cache);
1709 static struct io_buffer_list *io_buffer_get_list(struct io_ring_ctx *ctx,
1712 if (ctx->io_bl && bgid < BGID_ARRAY)
1713 return &ctx->io_bl[bgid];
1715 return xa_load(&ctx->io_bl_xa, bgid);
1718 static void io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags)
1720 struct io_ring_ctx *ctx = req->ctx;
1721 struct io_buffer_list *bl;
1722 struct io_buffer *buf;
1724 if (!(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING)))
1727 * For legacy provided buffer mode, don't recycle if we already did
1728 * IO to this buffer. For ring-mapped provided buffer mode, we should
1729 * increment ring->head to explicitly monopolize the buffer to avoid
1732 if ((req->flags & REQ_F_BUFFER_SELECTED) &&
1733 (req->flags & REQ_F_PARTIAL_IO))
1737 * We don't need to recycle for REQ_F_BUFFER_RING, we can just clear
1738 * the flag and hence ensure that bl->head doesn't get incremented.
1739 * If the tail has already been incremented, hang on to it.
1741 if (req->flags & REQ_F_BUFFER_RING) {
1742 if (req->buf_list) {
1743 if (req->flags & REQ_F_PARTIAL_IO) {
1744 req->buf_list->head++;
1745 req->buf_list = NULL;
1747 req->buf_index = req->buf_list->bgid;
1748 req->flags &= ~REQ_F_BUFFER_RING;
1754 io_ring_submit_lock(ctx, issue_flags);
1757 bl = io_buffer_get_list(ctx, buf->bgid);
1758 list_add(&buf->list, &bl->buf_list);
1759 req->flags &= ~REQ_F_BUFFER_SELECTED;
1760 req->buf_index = buf->bgid;
1762 io_ring_submit_unlock(ctx, issue_flags);
1765 static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
1767 __must_hold(&req->ctx->timeout_lock)
1769 struct io_kiocb *req;
1771 if (task && head->task != task)
1776 io_for_each_link(req, head) {
1777 if (req->flags & REQ_F_INFLIGHT)
1783 static bool io_match_linked(struct io_kiocb *head)
1785 struct io_kiocb *req;
1787 io_for_each_link(req, head) {
1788 if (req->flags & REQ_F_INFLIGHT)
1795 * As io_match_task() but protected against racing with linked timeouts.
1796 * User must not hold timeout_lock.
1798 static bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
1803 if (task && head->task != task)
1808 if (head->flags & REQ_F_LINK_TIMEOUT) {
1809 struct io_ring_ctx *ctx = head->ctx;
1811 /* protect against races with linked timeouts */
1812 spin_lock_irq(&ctx->timeout_lock);
1813 matched = io_match_linked(head);
1814 spin_unlock_irq(&ctx->timeout_lock);
1816 matched = io_match_linked(head);
1821 static inline bool req_has_async_data(struct io_kiocb *req)
1823 return req->flags & REQ_F_ASYNC_DATA;
1826 static inline void req_set_fail(struct io_kiocb *req)
1828 req->flags |= REQ_F_FAIL;
1829 if (req->flags & REQ_F_CQE_SKIP) {
1830 req->flags &= ~REQ_F_CQE_SKIP;
1831 req->flags |= REQ_F_SKIP_LINK_CQES;
1835 static inline void req_fail_link_node(struct io_kiocb *req, int res)
1841 static inline void io_req_add_to_cache(struct io_kiocb *req, struct io_ring_ctx *ctx)
1843 wq_stack_add_head(&req->comp_list, &ctx->submit_state.free_list);
1846 static __cold void io_ring_ctx_ref_free(struct percpu_ref *ref)
1848 struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
1850 complete(&ctx->ref_comp);
1853 static inline bool io_is_timeout_noseq(struct io_kiocb *req)
1855 return !req->timeout.off;
1858 static __cold void io_fallback_req_func(struct work_struct *work)
1860 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
1861 fallback_work.work);
1862 struct llist_node *node = llist_del_all(&ctx->fallback_llist);
1863 struct io_kiocb *req, *tmp;
1864 bool locked = false;
1866 percpu_ref_get(&ctx->refs);
1867 llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node)
1868 req->io_task_work.func(req, &locked);
1871 io_submit_flush_completions(ctx);
1872 mutex_unlock(&ctx->uring_lock);
1874 percpu_ref_put(&ctx->refs);
1877 static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
1879 struct io_ring_ctx *ctx;
1882 ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
1886 xa_init(&ctx->io_bl_xa);
1889 * Use 5 bits less than the max cq entries, that should give us around
1890 * 32 entries per hash list if totally full and uniformly spread.
1892 hash_bits = ilog2(p->cq_entries);
1896 ctx->cancel_hash_bits = hash_bits;
1897 ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
1899 if (!ctx->cancel_hash)
1901 __hash_init(ctx->cancel_hash, 1U << hash_bits);
1903 ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL);
1904 if (!ctx->dummy_ubuf)
1906 /* set invalid range, so io_import_fixed() fails meeting it */
1907 ctx->dummy_ubuf->ubuf = -1UL;
1909 if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
1910 PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
1913 ctx->flags = p->flags;
1914 init_waitqueue_head(&ctx->sqo_sq_wait);
1915 INIT_LIST_HEAD(&ctx->sqd_list);
1916 INIT_LIST_HEAD(&ctx->cq_overflow_list);
1917 INIT_LIST_HEAD(&ctx->io_buffers_cache);
1918 INIT_LIST_HEAD(&ctx->apoll_cache);
1919 init_completion(&ctx->ref_comp);
1920 xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
1921 mutex_init(&ctx->uring_lock);
1922 init_waitqueue_head(&ctx->cq_wait);
1923 spin_lock_init(&ctx->completion_lock);
1924 spin_lock_init(&ctx->timeout_lock);
1925 INIT_WQ_LIST(&ctx->iopoll_list);
1926 INIT_LIST_HEAD(&ctx->io_buffers_pages);
1927 INIT_LIST_HEAD(&ctx->io_buffers_comp);
1928 INIT_LIST_HEAD(&ctx->defer_list);
1929 INIT_LIST_HEAD(&ctx->timeout_list);
1930 INIT_LIST_HEAD(&ctx->ltimeout_list);
1931 spin_lock_init(&ctx->rsrc_ref_lock);
1932 INIT_LIST_HEAD(&ctx->rsrc_ref_list);
1933 INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
1934 init_llist_head(&ctx->rsrc_put_llist);
1935 INIT_LIST_HEAD(&ctx->tctx_list);
1936 ctx->submit_state.free_list.next = NULL;
1937 INIT_WQ_LIST(&ctx->locked_free_list);
1938 INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func);
1939 INIT_WQ_LIST(&ctx->submit_state.compl_reqs);
1942 kfree(ctx->dummy_ubuf);
1943 kfree(ctx->cancel_hash);
1945 xa_destroy(&ctx->io_bl_xa);
1950 static void io_account_cq_overflow(struct io_ring_ctx *ctx)
1952 struct io_rings *r = ctx->rings;
1954 WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1);
1958 static bool req_need_defer(struct io_kiocb *req, u32 seq)
1960 if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
1961 struct io_ring_ctx *ctx = req->ctx;
1963 return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail;
1969 static inline bool io_req_ffs_set(struct io_kiocb *req)
1971 return req->flags & REQ_F_FIXED_FILE;
1974 static inline void io_req_track_inflight(struct io_kiocb *req)
1976 if (!(req->flags & REQ_F_INFLIGHT)) {
1977 req->flags |= REQ_F_INFLIGHT;
1978 atomic_inc(¤t->io_uring->inflight_tracked);
1982 static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req)
1984 if (WARN_ON_ONCE(!req->link))
1987 req->flags &= ~REQ_F_ARM_LTIMEOUT;
1988 req->flags |= REQ_F_LINK_TIMEOUT;
1990 /* linked timeouts should have two refs once prep'ed */
1991 io_req_set_refcount(req);
1992 __io_req_set_refcount(req->link, 2);
1996 static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
1998 if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT)))
2000 return __io_prep_linked_timeout(req);
2003 static noinline void __io_arm_ltimeout(struct io_kiocb *req)
2005 io_queue_linked_timeout(__io_prep_linked_timeout(req));
2008 static inline void io_arm_ltimeout(struct io_kiocb *req)
2010 if (unlikely(req->flags & REQ_F_ARM_LTIMEOUT))
2011 __io_arm_ltimeout(req);
2014 static void io_prep_async_work(struct io_kiocb *req)
2016 const struct io_op_def *def = &io_op_defs[req->opcode];
2017 struct io_ring_ctx *ctx = req->ctx;
2019 if (!(req->flags & REQ_F_CREDS)) {
2020 req->flags |= REQ_F_CREDS;
2021 req->creds = get_current_cred();
2024 req->work.list.next = NULL;
2025 req->work.flags = 0;
2026 req->work.cancel_seq = atomic_read(&ctx->cancel_seq);
2027 if (req->flags & REQ_F_FORCE_ASYNC)
2028 req->work.flags |= IO_WQ_WORK_CONCURRENT;
2030 if (req->flags & REQ_F_ISREG) {
2031 if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
2032 io_wq_hash_work(&req->work, file_inode(req->file));
2033 } else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
2034 if (def->unbound_nonreg_file)
2035 req->work.flags |= IO_WQ_WORK_UNBOUND;
2039 static void io_prep_async_link(struct io_kiocb *req)
2041 struct io_kiocb *cur;
2043 if (req->flags & REQ_F_LINK_TIMEOUT) {
2044 struct io_ring_ctx *ctx = req->ctx;
2046 spin_lock_irq(&ctx->timeout_lock);
2047 io_for_each_link(cur, req)
2048 io_prep_async_work(cur);
2049 spin_unlock_irq(&ctx->timeout_lock);
2051 io_for_each_link(cur, req)
2052 io_prep_async_work(cur);
2056 static inline void io_req_add_compl_list(struct io_kiocb *req)
2058 struct io_submit_state *state = &req->ctx->submit_state;
2060 if (!(req->flags & REQ_F_CQE_SKIP))
2061 state->flush_cqes = true;
2062 wq_list_add_tail(&req->comp_list, &state->compl_reqs);
2065 static void io_queue_iowq(struct io_kiocb *req, bool *dont_use)
2067 struct io_kiocb *link = io_prep_linked_timeout(req);
2068 struct io_uring_task *tctx = req->task->io_uring;
2071 BUG_ON(!tctx->io_wq);
2073 /* init ->work of the whole link before punting */
2074 io_prep_async_link(req);
2077 * Not expected to happen, but if we do have a bug where this _can_
2078 * happen, catch it here and ensure the request is marked as
2079 * canceled. That will make io-wq go through the usual work cancel
2080 * procedure rather than attempt to run this request (or create a new
2083 if (WARN_ON_ONCE(!same_thread_group(req->task, current)))
2084 req->work.flags |= IO_WQ_WORK_CANCEL;
2086 trace_io_uring_queue_async_work(req->ctx, req, req->cqe.user_data,
2087 req->opcode, req->flags, &req->work,
2088 io_wq_is_hashed(&req->work));
2089 io_wq_enqueue(tctx->io_wq, &req->work);
2091 io_queue_linked_timeout(link);
2094 static void io_kill_timeout(struct io_kiocb *req, int status)
2095 __must_hold(&req->ctx->completion_lock)
2096 __must_hold(&req->ctx->timeout_lock)
2098 struct io_timeout_data *io = req->async_data;
2100 if (hrtimer_try_to_cancel(&io->timer) != -1) {
2103 atomic_set(&req->ctx->cq_timeouts,
2104 atomic_read(&req->ctx->cq_timeouts) + 1);
2105 list_del_init(&req->timeout.list);
2106 io_req_tw_post_queue(req, status, 0);
2110 static __cold void io_queue_deferred(struct io_ring_ctx *ctx)
2112 while (!list_empty(&ctx->defer_list)) {
2113 struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
2114 struct io_defer_entry, list);
2116 if (req_need_defer(de->req, de->seq))
2118 list_del_init(&de->list);
2119 io_req_task_queue(de->req);
2124 static __cold void io_flush_timeouts(struct io_ring_ctx *ctx)
2125 __must_hold(&ctx->completion_lock)
2127 u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
2128 struct io_kiocb *req, *tmp;
2130 spin_lock_irq(&ctx->timeout_lock);
2131 list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
2132 u32 events_needed, events_got;
2134 if (io_is_timeout_noseq(req))
2138 * Since seq can easily wrap around over time, subtract
2139 * the last seq at which timeouts were flushed before comparing.
2140 * Assuming not more than 2^31-1 events have happened since,
2141 * these subtractions won't have wrapped, so we can check if
2142 * target is in [last_seq, current_seq] by comparing the two.
2144 events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
2145 events_got = seq - ctx->cq_last_tm_flush;
2146 if (events_got < events_needed)
2149 io_kill_timeout(req, 0);
2151 ctx->cq_last_tm_flush = seq;
2152 spin_unlock_irq(&ctx->timeout_lock);
2155 static inline void io_commit_cqring(struct io_ring_ctx *ctx)
2157 /* order cqe stores with ring update */
2158 smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
2161 static void __io_commit_cqring_flush(struct io_ring_ctx *ctx)
2163 if (ctx->off_timeout_used || ctx->drain_active) {
2164 spin_lock(&ctx->completion_lock);
2165 if (ctx->off_timeout_used)
2166 io_flush_timeouts(ctx);
2167 if (ctx->drain_active)
2168 io_queue_deferred(ctx);
2169 io_commit_cqring(ctx);
2170 spin_unlock(&ctx->completion_lock);
2173 io_eventfd_signal(ctx);
2176 static inline bool io_sqring_full(struct io_ring_ctx *ctx)
2178 struct io_rings *r = ctx->rings;
2180 return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
2183 static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
2185 return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
2189 * writes to the cq entry need to come after reading head; the
2190 * control dependency is enough as we're using WRITE_ONCE to
2193 static noinline struct io_uring_cqe *__io_get_cqe(struct io_ring_ctx *ctx)
2195 struct io_rings *rings = ctx->rings;
2196 unsigned int off = ctx->cached_cq_tail & (ctx->cq_entries - 1);
2197 unsigned int shift = 0;
2198 unsigned int free, queued, len;
2200 if (ctx->flags & IORING_SETUP_CQE32)
2203 /* userspace may cheat modifying the tail, be safe and do min */
2204 queued = min(__io_cqring_events(ctx), ctx->cq_entries);
2205 free = ctx->cq_entries - queued;
2206 /* we need a contiguous range, limit based on the current array offset */
2207 len = min(free, ctx->cq_entries - off);
2211 ctx->cached_cq_tail++;
2212 ctx->cqe_cached = &rings->cqes[off];
2213 ctx->cqe_sentinel = ctx->cqe_cached + len;
2215 return &rings->cqes[off << shift];
2218 static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx)
2220 if (likely(ctx->cqe_cached < ctx->cqe_sentinel)) {
2221 struct io_uring_cqe *cqe = ctx->cqe_cached;
2223 if (ctx->flags & IORING_SETUP_CQE32) {
2224 unsigned int off = ctx->cqe_cached - ctx->rings->cqes;
2229 ctx->cached_cq_tail++;
2234 return __io_get_cqe(ctx);
2237 static void io_eventfd_signal(struct io_ring_ctx *ctx)
2239 struct io_ev_fd *ev_fd;
2243 * rcu_dereference ctx->io_ev_fd once and use it for both for checking
2244 * and eventfd_signal
2246 ev_fd = rcu_dereference(ctx->io_ev_fd);
2249 * Check again if ev_fd exists incase an io_eventfd_unregister call
2250 * completed between the NULL check of ctx->io_ev_fd at the start of
2251 * the function and rcu_read_lock.
2253 if (unlikely(!ev_fd))
2255 if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
2258 if (!ev_fd->eventfd_async || io_wq_current_is_worker())
2259 eventfd_signal(ev_fd->cq_ev_fd, 1);
2264 static inline void io_cqring_wake(struct io_ring_ctx *ctx)
2267 * wake_up_all() may seem excessive, but io_wake_function() and
2268 * io_should_wake() handle the termination of the loop and only
2269 * wake as many waiters as we need to.
2271 if (wq_has_sleeper(&ctx->cq_wait))
2272 wake_up_all(&ctx->cq_wait);
2276 * This should only get called when at least one event has been posted.
2277 * Some applications rely on the eventfd notification count only changing
2278 * IFF a new CQE has been added to the CQ ring. There's no depedency on
2279 * 1:1 relationship between how many times this function is called (and
2280 * hence the eventfd count) and number of CQEs posted to the CQ ring.
2282 static inline void io_cqring_ev_posted(struct io_ring_ctx *ctx)
2284 if (unlikely(ctx->off_timeout_used || ctx->drain_active ||
2286 __io_commit_cqring_flush(ctx);
2288 io_cqring_wake(ctx);
2291 static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
2293 if (unlikely(ctx->off_timeout_used || ctx->drain_active ||
2295 __io_commit_cqring_flush(ctx);
2297 if (ctx->flags & IORING_SETUP_SQPOLL)
2298 io_cqring_wake(ctx);
2301 /* Returns true if there are no backlogged entries after the flush */
2302 static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
2304 bool all_flushed, posted;
2305 size_t cqe_size = sizeof(struct io_uring_cqe);
2307 if (!force && __io_cqring_events(ctx) == ctx->cq_entries)
2310 if (ctx->flags & IORING_SETUP_CQE32)
2314 spin_lock(&ctx->completion_lock);
2315 while (!list_empty(&ctx->cq_overflow_list)) {
2316 struct io_uring_cqe *cqe = io_get_cqe(ctx);
2317 struct io_overflow_cqe *ocqe;
2321 ocqe = list_first_entry(&ctx->cq_overflow_list,
2322 struct io_overflow_cqe, list);
2324 memcpy(cqe, &ocqe->cqe, cqe_size);
2326 io_account_cq_overflow(ctx);
2329 list_del(&ocqe->list);
2333 all_flushed = list_empty(&ctx->cq_overflow_list);
2335 clear_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq);
2336 atomic_andnot(IORING_SQ_CQ_OVERFLOW, &ctx->rings->sq_flags);
2339 io_commit_cqring(ctx);
2340 spin_unlock(&ctx->completion_lock);
2342 io_cqring_ev_posted(ctx);
2346 static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx)
2350 if (test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq)) {
2351 /* iopoll syncs against uring_lock, not completion_lock */
2352 if (ctx->flags & IORING_SETUP_IOPOLL)
2353 mutex_lock(&ctx->uring_lock);
2354 ret = __io_cqring_overflow_flush(ctx, false);
2355 if (ctx->flags & IORING_SETUP_IOPOLL)
2356 mutex_unlock(&ctx->uring_lock);
2362 static void __io_put_task(struct task_struct *task, int nr)
2364 struct io_uring_task *tctx = task->io_uring;
2366 percpu_counter_sub(&tctx->inflight, nr);
2367 if (unlikely(atomic_read(&tctx->in_idle)))
2368 wake_up(&tctx->wait);
2369 put_task_struct_many(task, nr);
2372 /* must to be called somewhat shortly after putting a request */
2373 static inline void io_put_task(struct task_struct *task, int nr)
2375 if (likely(task == current))
2376 task->io_uring->cached_refs += nr;
2378 __io_put_task(task, nr);
2381 static void io_task_refs_refill(struct io_uring_task *tctx)
2383 unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR;
2385 percpu_counter_add(&tctx->inflight, refill);
2386 refcount_add(refill, ¤t->usage);
2387 tctx->cached_refs += refill;
2390 static inline void io_get_task_refs(int nr)
2392 struct io_uring_task *tctx = current->io_uring;
2394 tctx->cached_refs -= nr;
2395 if (unlikely(tctx->cached_refs < 0))
2396 io_task_refs_refill(tctx);
2399 static __cold void io_uring_drop_tctx_refs(struct task_struct *task)
2401 struct io_uring_task *tctx = task->io_uring;
2402 unsigned int refs = tctx->cached_refs;
2405 tctx->cached_refs = 0;
2406 percpu_counter_sub(&tctx->inflight, refs);
2407 put_task_struct_many(task, refs);
2411 static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data,
2412 s32 res, u32 cflags, u64 extra1,
2415 struct io_overflow_cqe *ocqe;
2416 size_t ocq_size = sizeof(struct io_overflow_cqe);
2417 bool is_cqe32 = (ctx->flags & IORING_SETUP_CQE32);
2420 ocq_size += sizeof(struct io_uring_cqe);
2422 ocqe = kmalloc(ocq_size, GFP_ATOMIC | __GFP_ACCOUNT);
2423 trace_io_uring_cqe_overflow(ctx, user_data, res, cflags, ocqe);
2426 * If we're in ring overflow flush mode, or in task cancel mode,
2427 * or cannot allocate an overflow entry, then we need to drop it
2430 io_account_cq_overflow(ctx);
2431 set_bit(IO_CHECK_CQ_DROPPED_BIT, &ctx->check_cq);
2434 if (list_empty(&ctx->cq_overflow_list)) {
2435 set_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq);
2436 atomic_or(IORING_SQ_CQ_OVERFLOW, &ctx->rings->sq_flags);
2439 ocqe->cqe.user_data = user_data;
2440 ocqe->cqe.res = res;
2441 ocqe->cqe.flags = cflags;
2443 ocqe->cqe.big_cqe[0] = extra1;
2444 ocqe->cqe.big_cqe[1] = extra2;
2446 list_add_tail(&ocqe->list, &ctx->cq_overflow_list);
2450 static inline bool __io_fill_cqe_req(struct io_ring_ctx *ctx,
2451 struct io_kiocb *req)
2453 struct io_uring_cqe *cqe;
2455 if (!(ctx->flags & IORING_SETUP_CQE32)) {
2456 trace_io_uring_complete(req->ctx, req, req->cqe.user_data,
2457 req->cqe.res, req->cqe.flags, 0, 0);
2460 * If we can't get a cq entry, userspace overflowed the
2461 * submission (by quite a lot). Increment the overflow count in
2464 cqe = io_get_cqe(ctx);
2466 memcpy(cqe, &req->cqe, sizeof(*cqe));
2470 return io_cqring_event_overflow(ctx, req->cqe.user_data,
2471 req->cqe.res, req->cqe.flags,
2474 u64 extra1 = 0, extra2 = 0;
2476 if (req->flags & REQ_F_CQE32_INIT) {
2477 extra1 = req->extra1;
2478 extra2 = req->extra2;
2481 trace_io_uring_complete(req->ctx, req, req->cqe.user_data,
2482 req->cqe.res, req->cqe.flags, extra1, extra2);
2485 * If we can't get a cq entry, userspace overflowed the
2486 * submission (by quite a lot). Increment the overflow count in
2489 cqe = io_get_cqe(ctx);
2491 memcpy(cqe, &req->cqe, sizeof(struct io_uring_cqe));
2492 WRITE_ONCE(cqe->big_cqe[0], extra1);
2493 WRITE_ONCE(cqe->big_cqe[1], extra2);
2497 return io_cqring_event_overflow(ctx, req->cqe.user_data,
2498 req->cqe.res, req->cqe.flags,
2503 static noinline bool io_fill_cqe_aux(struct io_ring_ctx *ctx, u64 user_data,
2504 s32 res, u32 cflags)
2506 struct io_uring_cqe *cqe;
2509 trace_io_uring_complete(ctx, NULL, user_data, res, cflags, 0, 0);
2512 * If we can't get a cq entry, userspace overflowed the
2513 * submission (by quite a lot). Increment the overflow count in
2516 cqe = io_get_cqe(ctx);
2518 WRITE_ONCE(cqe->user_data, user_data);
2519 WRITE_ONCE(cqe->res, res);
2520 WRITE_ONCE(cqe->flags, cflags);
2522 if (ctx->flags & IORING_SETUP_CQE32) {
2523 WRITE_ONCE(cqe->big_cqe[0], 0);
2524 WRITE_ONCE(cqe->big_cqe[1], 0);
2528 return io_cqring_event_overflow(ctx, user_data, res, cflags, 0, 0);
2531 static void __io_req_complete_put(struct io_kiocb *req)
2534 * If we're the last reference to this request, add to our locked
2537 if (req_ref_put_and_test(req)) {
2538 struct io_ring_ctx *ctx = req->ctx;
2540 if (req->flags & IO_REQ_LINK_FLAGS) {
2541 if (req->flags & IO_DISARM_MASK)
2542 io_disarm_next(req);
2544 io_req_task_queue(req->link);
2548 io_req_put_rsrc(req);
2550 * Selected buffer deallocation in io_clean_op() assumes that
2551 * we don't hold ->completion_lock. Clean them here to avoid
2554 io_put_kbuf_comp(req);
2555 io_dismantle_req(req);
2556 io_put_task(req->task, 1);
2557 wq_list_add_head(&req->comp_list, &ctx->locked_free_list);
2558 ctx->locked_free_nr++;
2562 static void __io_req_complete_post(struct io_kiocb *req, s32 res,
2565 if (!(req->flags & REQ_F_CQE_SKIP)) {
2567 req->cqe.flags = cflags;
2568 __io_fill_cqe_req(req->ctx, req);
2570 __io_req_complete_put(req);
2573 static void io_req_complete_post(struct io_kiocb *req, s32 res, u32 cflags)
2575 struct io_ring_ctx *ctx = req->ctx;
2577 spin_lock(&ctx->completion_lock);
2578 __io_req_complete_post(req, res, cflags);
2579 io_commit_cqring(ctx);
2580 spin_unlock(&ctx->completion_lock);
2581 io_cqring_ev_posted(ctx);
2584 static inline void io_req_complete_state(struct io_kiocb *req, s32 res,
2588 req->cqe.flags = cflags;
2589 req->flags |= REQ_F_COMPLETE_INLINE;
2592 static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
2593 s32 res, u32 cflags)
2595 if (issue_flags & IO_URING_F_COMPLETE_DEFER)
2596 io_req_complete_state(req, res, cflags);
2598 io_req_complete_post(req, res, cflags);
2601 static inline void io_req_complete(struct io_kiocb *req, s32 res)
2605 __io_req_complete(req, 0, res, 0);
2608 static void io_req_complete_failed(struct io_kiocb *req, s32 res)
2611 io_req_complete_post(req, res, io_put_kbuf(req, IO_URING_F_UNLOCKED));
2615 * Don't initialise the fields below on every allocation, but do that in
2616 * advance and keep them valid across allocations.
2618 static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx)
2622 req->async_data = NULL;
2623 /* not necessary, but safer to zero */
2627 static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx,
2628 struct io_submit_state *state)
2630 spin_lock(&ctx->completion_lock);
2631 wq_list_splice(&ctx->locked_free_list, &state->free_list);
2632 ctx->locked_free_nr = 0;
2633 spin_unlock(&ctx->completion_lock);
2636 static inline bool io_req_cache_empty(struct io_ring_ctx *ctx)
2638 return !ctx->submit_state.free_list.next;
2642 * A request might get retired back into the request caches even before opcode
2643 * handlers and io_issue_sqe() are done with it, e.g. inline completion path.
2644 * Because of that, io_alloc_req() should be called only under ->uring_lock
2645 * and with extra caution to not get a request that is still worked on.
2647 static __cold bool __io_alloc_req_refill(struct io_ring_ctx *ctx)
2648 __must_hold(&ctx->uring_lock)
2650 gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
2651 void *reqs[IO_REQ_ALLOC_BATCH];
2655 * If we have more than a batch's worth of requests in our IRQ side
2656 * locked cache, grab the lock and move them over to our submission
2659 if (data_race(ctx->locked_free_nr) > IO_COMPL_BATCH) {
2660 io_flush_cached_locked_reqs(ctx, &ctx->submit_state);
2661 if (!io_req_cache_empty(ctx))
2665 ret = kmem_cache_alloc_bulk(req_cachep, gfp, ARRAY_SIZE(reqs), reqs);
2668 * Bulk alloc is all-or-nothing. If we fail to get a batch,
2669 * retry single alloc to be on the safe side.
2671 if (unlikely(ret <= 0)) {
2672 reqs[0] = kmem_cache_alloc(req_cachep, gfp);
2678 percpu_ref_get_many(&ctx->refs, ret);
2679 for (i = 0; i < ret; i++) {
2680 struct io_kiocb *req = reqs[i];
2682 io_preinit_req(req, ctx);
2683 io_req_add_to_cache(req, ctx);
2688 static inline bool io_alloc_req_refill(struct io_ring_ctx *ctx)
2690 if (unlikely(io_req_cache_empty(ctx)))
2691 return __io_alloc_req_refill(ctx);
2695 static inline struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
2697 struct io_wq_work_node *node;
2699 node = wq_stack_extract(&ctx->submit_state.free_list);
2700 return container_of(node, struct io_kiocb, comp_list);
2703 static inline void io_put_file(struct file *file)
2709 static inline void io_dismantle_req(struct io_kiocb *req)
2711 unsigned int flags = req->flags;
2713 if (unlikely(flags & IO_REQ_CLEAN_FLAGS))
2715 if (!(flags & REQ_F_FIXED_FILE))
2716 io_put_file(req->file);
2719 static __cold void io_free_req(struct io_kiocb *req)
2721 struct io_ring_ctx *ctx = req->ctx;
2723 io_req_put_rsrc(req);
2724 io_dismantle_req(req);
2725 io_put_task(req->task, 1);
2727 spin_lock(&ctx->completion_lock);
2728 wq_list_add_head(&req->comp_list, &ctx->locked_free_list);
2729 ctx->locked_free_nr++;
2730 spin_unlock(&ctx->completion_lock);
2733 static inline void io_remove_next_linked(struct io_kiocb *req)
2735 struct io_kiocb *nxt = req->link;
2737 req->link = nxt->link;
2741 static struct io_kiocb *io_disarm_linked_timeout(struct io_kiocb *req)
2742 __must_hold(&req->ctx->completion_lock)
2743 __must_hold(&req->ctx->timeout_lock)
2745 struct io_kiocb *link = req->link;
2747 if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
2748 struct io_timeout_data *io = link->async_data;
2750 io_remove_next_linked(req);
2751 link->timeout.head = NULL;
2752 if (hrtimer_try_to_cancel(&io->timer) != -1) {
2753 list_del(&link->timeout.list);
2760 static void io_fail_links(struct io_kiocb *req)
2761 __must_hold(&req->ctx->completion_lock)
2763 struct io_kiocb *nxt, *link = req->link;
2764 bool ignore_cqes = req->flags & REQ_F_SKIP_LINK_CQES;
2768 long res = -ECANCELED;
2770 if (link->flags & REQ_F_FAIL)
2771 res = link->cqe.res;
2776 trace_io_uring_fail_link(req->ctx, req, req->cqe.user_data,
2780 link->flags |= REQ_F_CQE_SKIP;
2782 link->flags &= ~REQ_F_CQE_SKIP;
2783 __io_req_complete_post(link, res, 0);
2788 static bool io_disarm_next(struct io_kiocb *req)
2789 __must_hold(&req->ctx->completion_lock)
2791 struct io_kiocb *link = NULL;
2792 bool posted = false;
2794 if (req->flags & REQ_F_ARM_LTIMEOUT) {
2796 req->flags &= ~REQ_F_ARM_LTIMEOUT;
2797 if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
2798 io_remove_next_linked(req);
2799 io_req_tw_post_queue(link, -ECANCELED, 0);
2802 } else if (req->flags & REQ_F_LINK_TIMEOUT) {
2803 struct io_ring_ctx *ctx = req->ctx;
2805 spin_lock_irq(&ctx->timeout_lock);
2806 link = io_disarm_linked_timeout(req);
2807 spin_unlock_irq(&ctx->timeout_lock);
2810 io_req_tw_post_queue(link, -ECANCELED, 0);
2813 if (unlikely((req->flags & REQ_F_FAIL) &&
2814 !(req->flags & REQ_F_HARDLINK))) {
2815 posted |= (req->link != NULL);
2821 static void __io_req_find_next_prep(struct io_kiocb *req)
2823 struct io_ring_ctx *ctx = req->ctx;
2826 spin_lock(&ctx->completion_lock);
2827 posted = io_disarm_next(req);
2828 io_commit_cqring(ctx);
2829 spin_unlock(&ctx->completion_lock);
2831 io_cqring_ev_posted(ctx);
2834 static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
2836 struct io_kiocb *nxt;
2839 * If LINK is set, we have dependent requests in this chain. If we
2840 * didn't fail this request, queue the first one up, moving any other
2841 * dependencies to the next request. In case of failure, fail the rest
2844 if (unlikely(req->flags & IO_DISARM_MASK))
2845 __io_req_find_next_prep(req);
2851 static void ctx_flush_and_put(struct io_ring_ctx *ctx, bool *locked)
2855 if (ctx->flags & IORING_SETUP_TASKRUN_FLAG)
2856 atomic_andnot(IORING_SQ_TASKRUN, &ctx->rings->sq_flags);
2858 io_submit_flush_completions(ctx);
2859 mutex_unlock(&ctx->uring_lock);
2862 percpu_ref_put(&ctx->refs);
2865 static inline void ctx_commit_and_unlock(struct io_ring_ctx *ctx)
2867 io_commit_cqring(ctx);
2868 spin_unlock(&ctx->completion_lock);
2869 io_cqring_ev_posted(ctx);
2872 static void handle_prev_tw_list(struct io_wq_work_node *node,
2873 struct io_ring_ctx **ctx, bool *uring_locked)
2875 if (*ctx && !*uring_locked)
2876 spin_lock(&(*ctx)->completion_lock);
2879 struct io_wq_work_node *next = node->next;
2880 struct io_kiocb *req = container_of(node, struct io_kiocb,
2883 prefetch(container_of(next, struct io_kiocb, io_task_work.node));
2885 if (req->ctx != *ctx) {
2886 if (unlikely(!*uring_locked && *ctx))
2887 ctx_commit_and_unlock(*ctx);
2889 ctx_flush_and_put(*ctx, uring_locked);
2891 /* if not contended, grab and improve batching */
2892 *uring_locked = mutex_trylock(&(*ctx)->uring_lock);
2893 percpu_ref_get(&(*ctx)->refs);
2894 if (unlikely(!*uring_locked))
2895 spin_lock(&(*ctx)->completion_lock);
2897 if (likely(*uring_locked))
2898 req->io_task_work.func(req, uring_locked);
2900 __io_req_complete_post(req, req->cqe.res,
2901 io_put_kbuf_comp(req));
2905 if (unlikely(!*uring_locked))
2906 ctx_commit_and_unlock(*ctx);
2909 static void handle_tw_list(struct io_wq_work_node *node,
2910 struct io_ring_ctx **ctx, bool *locked)
2913 struct io_wq_work_node *next = node->next;
2914 struct io_kiocb *req = container_of(node, struct io_kiocb,
2917 prefetch(container_of(next, struct io_kiocb, io_task_work.node));
2919 if (req->ctx != *ctx) {
2920 ctx_flush_and_put(*ctx, locked);
2922 /* if not contended, grab and improve batching */
2923 *locked = mutex_trylock(&(*ctx)->uring_lock);
2924 percpu_ref_get(&(*ctx)->refs);
2926 req->io_task_work.func(req, locked);
2931 static void tctx_task_work(struct callback_head *cb)
2933 bool uring_locked = false;
2934 struct io_ring_ctx *ctx = NULL;
2935 struct io_uring_task *tctx = container_of(cb, struct io_uring_task,
2939 struct io_wq_work_node *node1, *node2;
2941 spin_lock_irq(&tctx->task_lock);
2942 node1 = tctx->prio_task_list.first;
2943 node2 = tctx->task_list.first;
2944 INIT_WQ_LIST(&tctx->task_list);
2945 INIT_WQ_LIST(&tctx->prio_task_list);
2946 if (!node2 && !node1)
2947 tctx->task_running = false;
2948 spin_unlock_irq(&tctx->task_lock);
2949 if (!node2 && !node1)
2953 handle_prev_tw_list(node1, &ctx, &uring_locked);
2955 handle_tw_list(node2, &ctx, &uring_locked);
2958 if (data_race(!tctx->task_list.first) &&
2959 data_race(!tctx->prio_task_list.first) && uring_locked)
2960 io_submit_flush_completions(ctx);
2963 ctx_flush_and_put(ctx, &uring_locked);
2965 /* relaxed read is enough as only the task itself sets ->in_idle */
2966 if (unlikely(atomic_read(&tctx->in_idle)))
2967 io_uring_drop_tctx_refs(current);
2970 static void __io_req_task_work_add(struct io_kiocb *req,
2971 struct io_uring_task *tctx,
2972 struct io_wq_work_list *list)
2974 struct io_ring_ctx *ctx = req->ctx;
2975 struct io_wq_work_node *node;
2976 unsigned long flags;
2979 spin_lock_irqsave(&tctx->task_lock, flags);
2980 wq_list_add_tail(&req->io_task_work.node, list);
2981 running = tctx->task_running;
2983 tctx->task_running = true;
2984 spin_unlock_irqrestore(&tctx->task_lock, flags);
2986 /* task_work already pending, we're done */
2990 if (ctx->flags & IORING_SETUP_TASKRUN_FLAG)
2991 atomic_or(IORING_SQ_TASKRUN, &ctx->rings->sq_flags);
2993 if (likely(!task_work_add(req->task, &tctx->task_work, ctx->notify_method)))
2996 spin_lock_irqsave(&tctx->task_lock, flags);
2997 tctx->task_running = false;
2998 node = wq_list_merge(&tctx->prio_task_list, &tctx->task_list);
2999 spin_unlock_irqrestore(&tctx->task_lock, flags);
3002 req = container_of(node, struct io_kiocb, io_task_work.node);
3004 if (llist_add(&req->io_task_work.fallback_node,
3005 &req->ctx->fallback_llist))
3006 schedule_delayed_work(&req->ctx->fallback_work, 1);
3010 static void io_req_task_work_add(struct io_kiocb *req)
3012 struct io_uring_task *tctx = req->task->io_uring;
3014 __io_req_task_work_add(req, tctx, &tctx->task_list);
3017 static void io_req_task_prio_work_add(struct io_kiocb *req)
3019 struct io_uring_task *tctx = req->task->io_uring;
3021 if (req->ctx->flags & IORING_SETUP_SQPOLL)
3022 __io_req_task_work_add(req, tctx, &tctx->prio_task_list);
3024 __io_req_task_work_add(req, tctx, &tctx->task_list);
3027 static void io_req_tw_post(struct io_kiocb *req, bool *locked)
3029 io_req_complete_post(req, req->cqe.res, req->cqe.flags);
3032 static void io_req_tw_post_queue(struct io_kiocb *req, s32 res, u32 cflags)
3035 req->cqe.flags = cflags;
3036 req->io_task_work.func = io_req_tw_post;
3037 io_req_task_work_add(req);
3040 static void io_req_task_cancel(struct io_kiocb *req, bool *locked)
3042 /* not needed for normal modes, but SQPOLL depends on it */
3043 io_tw_lock(req->ctx, locked);
3044 io_req_complete_failed(req, req->cqe.res);
3047 static void io_req_task_submit(struct io_kiocb *req, bool *locked)
3049 io_tw_lock(req->ctx, locked);
3050 /* req->task == current here, checking PF_EXITING is safe */
3051 if (likely(!(req->task->flags & PF_EXITING)))
3054 io_req_complete_failed(req, -EFAULT);
3057 static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
3060 req->io_task_work.func = io_req_task_cancel;
3061 io_req_task_work_add(req);
3064 static void io_req_task_queue(struct io_kiocb *req)
3066 req->io_task_work.func = io_req_task_submit;
3067 io_req_task_work_add(req);
3070 static void io_req_task_queue_reissue(struct io_kiocb *req)
3072 req->io_task_work.func = io_queue_iowq;
3073 io_req_task_work_add(req);
3076 static void io_queue_next(struct io_kiocb *req)
3078 struct io_kiocb *nxt = io_req_find_next(req);
3081 io_req_task_queue(nxt);
3084 static void io_free_batch_list(struct io_ring_ctx *ctx,
3085 struct io_wq_work_node *node)
3086 __must_hold(&ctx->uring_lock)
3088 struct task_struct *task = NULL;
3092 struct io_kiocb *req = container_of(node, struct io_kiocb,
3095 if (unlikely(req->flags & IO_REQ_CLEAN_SLOW_FLAGS)) {
3096 if (req->flags & REQ_F_REFCOUNT) {
3097 node = req->comp_list.next;
3098 if (!req_ref_put_and_test(req))
3101 if ((req->flags & REQ_F_POLLED) && req->apoll) {
3102 struct async_poll *apoll = req->apoll;
3104 if (apoll->double_poll)
3105 kfree(apoll->double_poll);
3106 list_add(&apoll->poll.wait.entry,
3108 req->flags &= ~REQ_F_POLLED;
3110 if (req->flags & IO_REQ_LINK_FLAGS)
3112 if (unlikely(req->flags & IO_REQ_CLEAN_FLAGS))
3115 if (!(req->flags & REQ_F_FIXED_FILE))
3116 io_put_file(req->file);
3118 io_req_put_rsrc_locked(req, ctx);
3120 if (req->task != task) {
3122 io_put_task(task, task_refs);
3127 node = req->comp_list.next;
3128 io_req_add_to_cache(req, ctx);
3132 io_put_task(task, task_refs);
3135 static void __io_submit_flush_completions(struct io_ring_ctx *ctx)
3136 __must_hold(&ctx->uring_lock)
3138 struct io_wq_work_node *node, *prev;
3139 struct io_submit_state *state = &ctx->submit_state;
3141 if (state->flush_cqes) {
3142 spin_lock(&ctx->completion_lock);
3143 wq_list_for_each(node, prev, &state->compl_reqs) {
3144 struct io_kiocb *req = container_of(node, struct io_kiocb,
3147 if (!(req->flags & REQ_F_CQE_SKIP))
3148 __io_fill_cqe_req(ctx, req);
3151 io_commit_cqring(ctx);
3152 spin_unlock(&ctx->completion_lock);
3153 io_cqring_ev_posted(ctx);
3154 state->flush_cqes = false;
3157 io_free_batch_list(ctx, state->compl_reqs.first);
3158 INIT_WQ_LIST(&state->compl_reqs);
3162 * Drop reference to request, return next in chain (if there is one) if this
3163 * was the last reference to this request.
3165 static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
3167 struct io_kiocb *nxt = NULL;
3169 if (req_ref_put_and_test(req)) {
3170 if (unlikely(req->flags & IO_REQ_LINK_FLAGS))
3171 nxt = io_req_find_next(req);
3177 static inline void io_put_req(struct io_kiocb *req)
3179 if (req_ref_put_and_test(req)) {
3185 static unsigned io_cqring_events(struct io_ring_ctx *ctx)
3187 /* See comment at the top of this file */
3189 return __io_cqring_events(ctx);
3192 static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
3194 struct io_rings *rings = ctx->rings;
3196 /* make sure SQ entry isn't read before tail */
3197 return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
3200 static inline bool io_run_task_work(void)
3202 if (test_thread_flag(TIF_NOTIFY_SIGNAL) || task_work_pending(current)) {
3203 __set_current_state(TASK_RUNNING);
3204 clear_notify_signal();
3205 if (task_work_pending(current))
3213 static int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin)
3215 struct io_wq_work_node *pos, *start, *prev;
3216 unsigned int poll_flags = BLK_POLL_NOSLEEP;
3217 DEFINE_IO_COMP_BATCH(iob);
3221 * Only spin for completions if we don't have multiple devices hanging
3222 * off our complete list.
3224 if (ctx->poll_multi_queue || force_nonspin)
3225 poll_flags |= BLK_POLL_ONESHOT;
3227 wq_list_for_each(pos, start, &ctx->iopoll_list) {
3228 struct io_kiocb *req = container_of(pos, struct io_kiocb, comp_list);
3229 struct kiocb *kiocb = &req->rw.kiocb;
3233 * Move completed and retryable entries to our local lists.
3234 * If we find a request that requires polling, break out
3235 * and complete those lists first, if we have entries there.
3237 if (READ_ONCE(req->iopoll_completed))
3240 ret = kiocb->ki_filp->f_op->iopoll(kiocb, &iob, poll_flags);
3241 if (unlikely(ret < 0))
3244 poll_flags |= BLK_POLL_ONESHOT;
3246 /* iopoll may have completed current req */
3247 if (!rq_list_empty(iob.req_list) ||
3248 READ_ONCE(req->iopoll_completed))
3252 if (!rq_list_empty(iob.req_list))
3258 wq_list_for_each_resume(pos, prev) {
3259 struct io_kiocb *req = container_of(pos, struct io_kiocb, comp_list);
3261 /* order with io_complete_rw_iopoll(), e.g. ->result updates */
3262 if (!smp_load_acquire(&req->iopoll_completed))
3265 if (unlikely(req->flags & REQ_F_CQE_SKIP))
3268 req->cqe.flags = io_put_kbuf(req, 0);
3269 __io_fill_cqe_req(req->ctx, req);
3272 if (unlikely(!nr_events))
3275 io_commit_cqring(ctx);
3276 io_cqring_ev_posted_iopoll(ctx);
3277 pos = start ? start->next : ctx->iopoll_list.first;
3278 wq_list_cut(&ctx->iopoll_list, prev, start);
3279 io_free_batch_list(ctx, pos);
3284 * We can't just wait for polled events to come to us, we have to actively
3285 * find and complete them.
3287 static __cold void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
3289 if (!(ctx->flags & IORING_SETUP_IOPOLL))
3292 mutex_lock(&ctx->uring_lock);
3293 while (!wq_list_empty(&ctx->iopoll_list)) {
3294 /* let it sleep and repeat later if can't complete a request */
3295 if (io_do_iopoll(ctx, true) == 0)
3298 * Ensure we allow local-to-the-cpu processing to take place,
3299 * in this case we need to ensure that we reap all events.
3300 * Also let task_work, etc. to progress by releasing the mutex
3302 if (need_resched()) {
3303 mutex_unlock(&ctx->uring_lock);
3305 mutex_lock(&ctx->uring_lock);
3308 mutex_unlock(&ctx->uring_lock);
3311 static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
3313 unsigned int nr_events = 0;
3315 unsigned long check_cq;
3318 * Don't enter poll loop if we already have events pending.
3319 * If we do, we can potentially be spinning for commands that
3320 * already triggered a CQE (eg in error).
3322 check_cq = READ_ONCE(ctx->check_cq);
3323 if (check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT))
3324 __io_cqring_overflow_flush(ctx, false);
3325 if (io_cqring_events(ctx))
3329 * Similarly do not spin if we have not informed the user of any
3332 if (unlikely(check_cq & BIT(IO_CHECK_CQ_DROPPED_BIT)))
3337 * If a submit got punted to a workqueue, we can have the
3338 * application entering polling for a command before it gets
3339 * issued. That app will hold the uring_lock for the duration
3340 * of the poll right here, so we need to take a breather every
3341 * now and then to ensure that the issue has a chance to add
3342 * the poll to the issued list. Otherwise we can spin here
3343 * forever, while the workqueue is stuck trying to acquire the
3346 if (wq_list_empty(&ctx->iopoll_list)) {
3347 u32 tail = ctx->cached_cq_tail;
3349 mutex_unlock(&ctx->uring_lock);
3351 mutex_lock(&ctx->uring_lock);
3353 /* some requests don't go through iopoll_list */
3354 if (tail != ctx->cached_cq_tail ||
3355 wq_list_empty(&ctx->iopoll_list))
3358 ret = io_do_iopoll(ctx, !min);
3363 } while (nr_events < min && !need_resched());
3368 static void kiocb_end_write(struct io_kiocb *req)
3371 * Tell lockdep we inherited freeze protection from submission
3374 if (req->flags & REQ_F_ISREG) {
3375 struct super_block *sb = file_inode(req->file)->i_sb;
3377 __sb_writers_acquired(sb, SB_FREEZE_WRITE);
3383 static bool io_resubmit_prep(struct io_kiocb *req)
3385 struct io_async_rw *rw = req->async_data;
3387 if (!req_has_async_data(req))
3388 return !io_req_prep_async(req);
3389 iov_iter_restore(&rw->s.iter, &rw->s.iter_state);
3393 static bool io_rw_should_reissue(struct io_kiocb *req)
3395 umode_t mode = file_inode(req->file)->i_mode;
3396 struct io_ring_ctx *ctx = req->ctx;
3398 if (!S_ISBLK(mode) && !S_ISREG(mode))
3400 if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
3401 !(ctx->flags & IORING_SETUP_IOPOLL)))
3404 * If ref is dying, we might be running poll reap from the exit work.
3405 * Don't attempt to reissue from that path, just let it fail with
3408 if (percpu_ref_is_dying(&ctx->refs))
3411 * Play it safe and assume not safe to re-import and reissue if we're
3412 * not in the original thread group (or in task context).
3414 if (!same_thread_group(req->task, current) || !in_task())
3419 static bool io_resubmit_prep(struct io_kiocb *req)
3423 static bool io_rw_should_reissue(struct io_kiocb *req)
3429 static bool __io_complete_rw_common(struct io_kiocb *req, long res)
3431 if (req->rw.kiocb.ki_flags & IOCB_WRITE) {
3432 kiocb_end_write(req);
3433 fsnotify_modify(req->file);
3435 fsnotify_access(req->file);
3437 if (unlikely(res != req->cqe.res)) {
3438 if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
3439 io_rw_should_reissue(req)) {
3440 req->flags |= REQ_F_REISSUE;
3449 static inline void io_req_task_complete(struct io_kiocb *req, bool *locked)
3451 int res = req->cqe.res;
3454 io_req_complete_state(req, res, io_put_kbuf(req, 0));
3455 io_req_add_compl_list(req);
3457 io_req_complete_post(req, res,
3458 io_put_kbuf(req, IO_URING_F_UNLOCKED));
3462 static void __io_complete_rw(struct io_kiocb *req, long res,
3463 unsigned int issue_flags)
3465 if (__io_complete_rw_common(req, res))
3467 __io_req_complete(req, issue_flags, req->cqe.res,
3468 io_put_kbuf(req, issue_flags));
3471 static void io_complete_rw(struct kiocb *kiocb, long res)
3473 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
3475 if (__io_complete_rw_common(req, res))
3478 req->io_task_work.func = io_req_task_complete;
3479 io_req_task_prio_work_add(req);
3482 static void io_complete_rw_iopoll(struct kiocb *kiocb, long res)
3484 struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
3486 if (kiocb->ki_flags & IOCB_WRITE)
3487 kiocb_end_write(req);
3488 if (unlikely(res != req->cqe.res)) {
3489 if (res == -EAGAIN && io_rw_should_reissue(req)) {
3490 req->flags |= REQ_F_REISSUE;
3496 /* order with io_iopoll_complete() checking ->iopoll_completed */
3497 smp_store_release(&req->iopoll_completed, 1);
3501 * After the iocb has been issued, it's safe to be found on the poll list.
3502 * Adding the kiocb to the list AFTER submission ensures that we don't
3503 * find it from a io_do_iopoll() thread before the issuer is done
3504 * accessing the kiocb cookie.
3506 static void io_iopoll_req_issued(struct io_kiocb *req, unsigned int issue_flags)
3508 struct io_ring_ctx *ctx = req->ctx;
3509 const bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
3511 /* workqueue context doesn't hold uring_lock, grab it now */
3512 if (unlikely(needs_lock))
3513 mutex_lock(&ctx->uring_lock);
3516 * Track whether we have multiple files in our lists. This will impact
3517 * how we do polling eventually, not spinning if we're on potentially
3518 * different devices.
3520 if (wq_list_empty(&ctx->iopoll_list)) {
3521 ctx->poll_multi_queue = false;
3522 } else if (!ctx->poll_multi_queue) {
3523 struct io_kiocb *list_req;
3525 list_req = container_of(ctx->iopoll_list.first, struct io_kiocb,
3527 if (list_req->file != req->file)
3528 ctx->poll_multi_queue = true;
3532 * For fast devices, IO may have already completed. If it has, add
3533 * it to the front so we find it first.
3535 if (READ_ONCE(req->iopoll_completed))
3536 wq_list_add_head(&req->comp_list, &ctx->iopoll_list);
3538 wq_list_add_tail(&req->comp_list, &ctx->iopoll_list);
3540 if (unlikely(needs_lock)) {
3542 * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
3543 * in sq thread task context or in io worker task context. If
3544 * current task context is sq thread, we don't need to check
3545 * whether should wake up sq thread.
3547 if ((ctx->flags & IORING_SETUP_SQPOLL) &&
3548 wq_has_sleeper(&ctx->sq_data->wait))
3549 wake_up(&ctx->sq_data->wait);
3551 mutex_unlock(&ctx->uring_lock);
3555 static bool io_bdev_nowait(struct block_device *bdev)
3557 return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
3561 * If we tracked the file through the SCM inflight mechanism, we could support
3562 * any file. For now, just ensure that anything potentially problematic is done
3565 static bool __io_file_supports_nowait(struct file *file, umode_t mode)
3567 if (S_ISBLK(mode)) {
3568 if (IS_ENABLED(CONFIG_BLOCK) &&
3569 io_bdev_nowait(I_BDEV(file->f_mapping->host)))
3575 if (S_ISREG(mode)) {
3576 if (IS_ENABLED(CONFIG_BLOCK) &&
3577 io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
3578 file->f_op != &io_uring_fops)
3583 /* any ->read/write should understand O_NONBLOCK */
3584 if (file->f_flags & O_NONBLOCK)
3586 return file->f_mode & FMODE_NOWAIT;
3590 * If we tracked the file through the SCM inflight mechanism, we could support
3591 * any file. For now, just ensure that anything potentially problematic is done
3594 static unsigned int io_file_get_flags(struct file *file)
3596 umode_t mode = file_inode(file)->i_mode;
3597 unsigned int res = 0;
3601 if (__io_file_supports_nowait(file, mode))
3603 if (io_file_need_scm(file))
3608 static inline bool io_file_supports_nowait(struct io_kiocb *req)
3610 return req->flags & REQ_F_SUPPORT_NOWAIT;
3613 static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
3615 struct kiocb *kiocb = &req->rw.kiocb;
3619 kiocb->ki_pos = READ_ONCE(sqe->off);
3620 /* used for fixed read/write too - just read unconditionally */
3621 req->buf_index = READ_ONCE(sqe->buf_index);
3623 if (req->opcode == IORING_OP_READ_FIXED ||
3624 req->opcode == IORING_OP_WRITE_FIXED) {
3625 struct io_ring_ctx *ctx = req->ctx;
3628 if (unlikely(req->buf_index >= ctx->nr_user_bufs))
3630 index = array_index_nospec(req->buf_index, ctx->nr_user_bufs);
3631 req->imu = ctx->user_bufs[index];
3632 io_req_set_rsrc_node(req, ctx, 0);
3635 ioprio = READ_ONCE(sqe->ioprio);
3637 ret = ioprio_check_cap(ioprio);
3641 kiocb->ki_ioprio = ioprio;
3643 kiocb->ki_ioprio = get_current_ioprio();
3646 req->rw.addr = READ_ONCE(sqe->addr);
3647 req->rw.len = READ_ONCE(sqe->len);
3648 req->rw.flags = READ_ONCE(sqe->rw_flags);
3652 static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
3658 case -ERESTARTNOINTR:
3659 case -ERESTARTNOHAND:
3660 case -ERESTART_RESTARTBLOCK:
3662 * We can't just restart the syscall, since previously
3663 * submitted sqes may already be in progress. Just fail this
3669 kiocb->ki_complete(kiocb, ret);
3673 static inline loff_t *io_kiocb_update_pos(struct io_kiocb *req)
3675 struct kiocb *kiocb = &req->rw.kiocb;
3677 if (kiocb->ki_pos != -1)
3678 return &kiocb->ki_pos;
3680 if (!(req->file->f_mode & FMODE_STREAM)) {
3681 req->flags |= REQ_F_CUR_POS;
3682 kiocb->ki_pos = req->file->f_pos;
3683 return &kiocb->ki_pos;
3690 static void kiocb_done(struct io_kiocb *req, ssize_t ret,
3691 unsigned int issue_flags)
3693 struct io_async_rw *io = req->async_data;
3695 /* add previously done IO, if any */
3696 if (req_has_async_data(req) && io->bytes_done > 0) {
3698 ret = io->bytes_done;
3700 ret += io->bytes_done;
3703 if (req->flags & REQ_F_CUR_POS)
3704 req->file->f_pos = req->rw.kiocb.ki_pos;
3705 if (ret >= 0 && (req->rw.kiocb.ki_complete == io_complete_rw))
3706 __io_complete_rw(req, ret, issue_flags);
3708 io_rw_done(&req->rw.kiocb, ret);
3710 if (req->flags & REQ_F_REISSUE) {
3711 req->flags &= ~REQ_F_REISSUE;
3712 if (io_resubmit_prep(req))
3713 io_req_task_queue_reissue(req);
3715 io_req_task_queue_fail(req, ret);
3719 static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
3720 struct io_mapped_ubuf *imu)
3722 size_t len = req->rw.len;
3723 u64 buf_end, buf_addr = req->rw.addr;
3726 if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
3728 /* not inside the mapped region */
3729 if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
3733 * May not be a start of buffer, set size appropriately
3734 * and advance us to the beginning.
3736 offset = buf_addr - imu->ubuf;
3737 iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
3741 * Don't use iov_iter_advance() here, as it's really slow for
3742 * using the latter parts of a big fixed buffer - it iterates
3743 * over each segment manually. We can cheat a bit here, because
3746 * 1) it's a BVEC iter, we set it up
3747 * 2) all bvecs are PAGE_SIZE in size, except potentially the
3748 * first and last bvec
3750 * So just find our index, and adjust the iterator afterwards.
3751 * If the offset is within the first bvec (or the whole first
3752 * bvec, just use iov_iter_advance(). This makes it easier
3753 * since we can just skip the first segment, which may not
3754 * be PAGE_SIZE aligned.
3756 const struct bio_vec *bvec = imu->bvec;
3758 if (offset <= bvec->bv_len) {
3759 iov_iter_advance(iter, offset);
3761 unsigned long seg_skip;
3763 /* skip first vec */
3764 offset -= bvec->bv_len;
3765 seg_skip = 1 + (offset >> PAGE_SHIFT);
3767 iter->bvec = bvec + seg_skip;
3768 iter->nr_segs -= seg_skip;
3769 iter->count -= bvec->bv_len + offset;
3770 iter->iov_offset = offset & ~PAGE_MASK;
3777 static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
3778 unsigned int issue_flags)
3780 if (WARN_ON_ONCE(!req->imu))
3782 return __io_import_fixed(req, rw, iter, req->imu);
3785 static int io_buffer_add_list(struct io_ring_ctx *ctx,
3786 struct io_buffer_list *bl, unsigned int bgid)
3789 if (bgid < BGID_ARRAY)
3792 return xa_err(xa_store(&ctx->io_bl_xa, bgid, bl, GFP_KERNEL));
3795 static void __user *io_provided_buffer_select(struct io_kiocb *req, size_t *len,
3796 struct io_buffer_list *bl)
3798 if (!list_empty(&bl->buf_list)) {
3799 struct io_buffer *kbuf;
3801 kbuf = list_first_entry(&bl->buf_list, struct io_buffer, list);
3802 list_del(&kbuf->list);
3803 if (*len > kbuf->len)
3805 req->flags |= REQ_F_BUFFER_SELECTED;
3807 req->buf_index = kbuf->bid;
3808 return u64_to_user_ptr(kbuf->addr);
3813 static void __user *io_ring_buffer_select(struct io_kiocb *req, size_t *len,
3814 struct io_buffer_list *bl,
3815 unsigned int issue_flags)
3817 struct io_uring_buf_ring *br = bl->buf_ring;
3818 struct io_uring_buf *buf;
3819 __u16 head = bl->head;
3821 if (unlikely(smp_load_acquire(&br->tail) == head))
3825 if (head < IO_BUFFER_LIST_BUF_PER_PAGE) {
3826 buf = &br->bufs[head];
3828 int off = head & (IO_BUFFER_LIST_BUF_PER_PAGE - 1);
3829 int index = head / IO_BUFFER_LIST_BUF_PER_PAGE;
3830 buf = page_address(bl->buf_pages[index]);
3833 if (*len > buf->len)
3835 req->flags |= REQ_F_BUFFER_RING;
3837 req->buf_index = buf->bid;
3839 if (issue_flags & IO_URING_F_UNLOCKED || !file_can_poll(req->file)) {
3841 * If we came in unlocked, we have no choice but to consume the
3842 * buffer here. This does mean it'll be pinned until the IO
3843 * completes. But coming in unlocked means we're in io-wq
3844 * context, hence there should be no further retry. For the
3845 * locked case, the caller must ensure to call the commit when
3846 * the transfer completes (or if we get -EAGAIN and must poll
3849 req->buf_list = NULL;
3852 return u64_to_user_ptr(buf->addr);
3855 static void __user *io_buffer_select(struct io_kiocb *req, size_t *len,
3856 unsigned int issue_flags)
3858 struct io_ring_ctx *ctx = req->ctx;
3859 struct io_buffer_list *bl;
3860 void __user *ret = NULL;
3862 io_ring_submit_lock(req->ctx, issue_flags);
3864 bl = io_buffer_get_list(ctx, req->buf_index);
3866 if (bl->buf_nr_pages)
3867 ret = io_ring_buffer_select(req, len, bl, issue_flags);
3869 ret = io_provided_buffer_select(req, len, bl);
3871 io_ring_submit_unlock(req->ctx, issue_flags);
3875 #ifdef CONFIG_COMPAT
3876 static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
3877 unsigned int issue_flags)
3879 struct compat_iovec __user *uiov;
3880 compat_ssize_t clen;
3884 uiov = u64_to_user_ptr(req->rw.addr);
3885 if (!access_ok(uiov, sizeof(*uiov)))
3887 if (__get_user(clen, &uiov->iov_len))
3893 buf = io_buffer_select(req, &len, issue_flags);
3896 req->rw.addr = (unsigned long) buf;
3897 iov[0].iov_base = buf;
3898 req->rw.len = iov[0].iov_len = (compat_size_t) len;
3903 static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
3904 unsigned int issue_flags)
3906 struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
3910 if (copy_from_user(iov, uiov, sizeof(*uiov)))
3913 len = iov[0].iov_len;
3916 buf = io_buffer_select(req, &len, issue_flags);
3919 req->rw.addr = (unsigned long) buf;
3920 iov[0].iov_base = buf;
3921 req->rw.len = iov[0].iov_len = len;
3925 static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
3926 unsigned int issue_flags)
3928 if (req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING)) {
3929 iov[0].iov_base = u64_to_user_ptr(req->rw.addr);
3930 iov[0].iov_len = req->rw.len;
3933 if (req->rw.len != 1)
3936 #ifdef CONFIG_COMPAT
3937 if (req->ctx->compat)
3938 return io_compat_import(req, iov, issue_flags);
3941 return __io_iov_buffer_select(req, iov, issue_flags);
3944 static inline bool io_do_buffer_select(struct io_kiocb *req)
3946 if (!(req->flags & REQ_F_BUFFER_SELECT))
3948 return !(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING));
3951 static struct iovec *__io_import_iovec(int rw, struct io_kiocb *req,
3952 struct io_rw_state *s,
3953 unsigned int issue_flags)
3955 struct iov_iter *iter = &s->iter;
3956 u8 opcode = req->opcode;
3957 struct iovec *iovec;
3962 if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) {
3963 ret = io_import_fixed(req, rw, iter, issue_flags);
3965 return ERR_PTR(ret);
3969 buf = u64_to_user_ptr(req->rw.addr);
3970 sqe_len = req->rw.len;
3972 if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
3973 if (io_do_buffer_select(req)) {
3974 buf = io_buffer_select(req, &sqe_len, issue_flags);
3976 return ERR_PTR(-ENOBUFS);
3977 req->rw.addr = (unsigned long) buf;
3978 req->rw.len = sqe_len;
3981 ret = import_single_range(rw, buf, sqe_len, s->fast_iov, iter);
3983 return ERR_PTR(ret);
3987 iovec = s->fast_iov;
3988 if (req->flags & REQ_F_BUFFER_SELECT) {
3989 ret = io_iov_buffer_select(req, iovec, issue_flags);
3991 return ERR_PTR(ret);
3992 iov_iter_init(iter, rw, iovec, 1, iovec->iov_len);
3996 ret = __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, &iovec, iter,
3998 if (unlikely(ret < 0))
3999 return ERR_PTR(ret);
4003 static inline int io_import_iovec(int rw, struct io_kiocb *req,
4004 struct iovec **iovec, struct io_rw_state *s,
4005 unsigned int issue_flags)
4007 *iovec = __io_import_iovec(rw, req, s, issue_flags);
4008 if (unlikely(IS_ERR(*iovec)))
4009 return PTR_ERR(*iovec);
4011 iov_iter_save_state(&s->iter, &s->iter_state);
4015 static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
4017 return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
4021 * For files that don't have ->read_iter() and ->write_iter(), handle them
4022 * by looping over ->read() or ->write() manually.
4024 static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
4026 struct kiocb *kiocb = &req->rw.kiocb;
4027 struct file *file = req->file;
4032 * Don't support polled IO through this interface, and we can't
4033 * support non-blocking either. For the latter, this just causes
4034 * the kiocb to be handled from an async context.
4036 if (kiocb->ki_flags & IOCB_HIPRI)
4038 if ((kiocb->ki_flags & IOCB_NOWAIT) &&
4039 !(kiocb->ki_filp->f_flags & O_NONBLOCK))
4042 ppos = io_kiocb_ppos(kiocb);
4044 while (iov_iter_count(iter)) {
4048 if (!iov_iter_is_bvec(iter)) {
4049 iovec = iov_iter_iovec(iter);
4051 iovec.iov_base = u64_to_user_ptr(req->rw.addr);
4052 iovec.iov_len = req->rw.len;
4056 nr = file->f_op->read(file, iovec.iov_base,
4057 iovec.iov_len, ppos);
4059 nr = file->f_op->write(file, iovec.iov_base,
4060 iovec.iov_len, ppos);
4069 if (!iov_iter_is_bvec(iter)) {
4070 iov_iter_advance(iter, nr);
4077 if (nr != iovec.iov_len)
4084 static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
4085 const struct iovec *fast_iov, struct iov_iter *iter)
4087 struct io_async_rw *rw = req->async_data;
4089 memcpy(&rw->s.iter, iter, sizeof(*iter));
4090 rw->free_iovec = iovec;
4092 /* can only be fixed buffers, no need to do anything */
4093 if (iov_iter_is_bvec(iter))
4096 unsigned iov_off = 0;
4098 rw->s.iter.iov = rw->s.fast_iov;
4099 if (iter->iov != fast_iov) {
4100 iov_off = iter->iov - fast_iov;
4101 rw->s.iter.iov += iov_off;
4103 if (rw->s.fast_iov != fast_iov)
4104 memcpy(rw->s.fast_iov + iov_off, fast_iov + iov_off,
4105 sizeof(struct iovec) * iter->nr_segs);
4107 req->flags |= REQ_F_NEED_CLEANUP;
4111 static inline bool io_alloc_async_data(struct io_kiocb *req)
4113 WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
4114 req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
4115 if (req->async_data) {
4116 req->flags |= REQ_F_ASYNC_DATA;
4122 static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
4123 struct io_rw_state *s, bool force)
4125 if (!force && !io_op_defs[req->opcode].needs_async_setup)
4127 if (!req_has_async_data(req)) {
4128 struct io_async_rw *iorw;
4130 if (io_alloc_async_data(req)) {
4135 io_req_map_rw(req, iovec, s->fast_iov, &s->iter);
4136 iorw = req->async_data;
4137 /* we've copied and mapped the iter, ensure state is saved */
4138 iov_iter_save_state(&iorw->s.iter, &iorw->s.iter_state);
4143 static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
4145 struct io_async_rw *iorw = req->async_data;
4149 /* submission path, ->uring_lock should already be taken */
4150 ret = io_import_iovec(rw, req, &iov, &iorw->s, 0);
4151 if (unlikely(ret < 0))
4154 iorw->bytes_done = 0;
4155 iorw->free_iovec = iov;
4157 req->flags |= REQ_F_NEED_CLEANUP;
4161 static int io_readv_prep_async(struct io_kiocb *req)
4163 return io_rw_prep_async(req, READ);
4166 static int io_writev_prep_async(struct io_kiocb *req)
4168 return io_rw_prep_async(req, WRITE);
4172 * This is our waitqueue callback handler, registered through __folio_lock_async()
4173 * when we initially tried to do the IO with the iocb armed our waitqueue.
4174 * This gets called when the page is unlocked, and we generally expect that to
4175 * happen when the page IO is completed and the page is now uptodate. This will
4176 * queue a task_work based retry of the operation, attempting to copy the data
4177 * again. If the latter fails because the page was NOT uptodate, then we will
4178 * do a thread based blocking retry of the operation. That's the unexpected
4181 static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
4182 int sync, void *arg)
4184 struct wait_page_queue *wpq;
4185 struct io_kiocb *req = wait->private;
4186 struct wait_page_key *key = arg;
4188 wpq = container_of(wait, struct wait_page_queue, wait);
4190 if (!wake_page_match(wpq, key))
4193 req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
4194 list_del_init(&wait->entry);
4195 io_req_task_queue(req);
4200 * This controls whether a given IO request should be armed for async page
4201 * based retry. If we return false here, the request is handed to the async
4202 * worker threads for retry. If we're doing buffered reads on a regular file,
4203 * we prepare a private wait_page_queue entry and retry the operation. This
4204 * will either succeed because the page is now uptodate and unlocked, or it
4205 * will register a callback when the page is unlocked at IO completion. Through
4206 * that callback, io_uring uses task_work to setup a retry of the operation.
4207 * That retry will attempt the buffered read again. The retry will generally
4208 * succeed, or in rare cases where it fails, we then fall back to using the
4209 * async worker threads for a blocking retry.
4211 static bool io_rw_should_retry(struct io_kiocb *req)
4213 struct io_async_rw *rw = req->async_data;
4214 struct wait_page_queue *wait = &rw->wpq;
4215 struct kiocb *kiocb = &req->rw.kiocb;
4217 /* never retry for NOWAIT, we just complete with -EAGAIN */
4218 if (req->flags & REQ_F_NOWAIT)
4221 /* Only for buffered IO */
4222 if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
4226 * just use poll if we can, and don't attempt if the fs doesn't
4227 * support callback based unlocks
4229 if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
4232 wait->wait.func = io_async_buf_func;
4233 wait->wait.private = req;
4234 wait->wait.flags = 0;
4235 INIT_LIST_HEAD(&wait->wait.entry);
4236 kiocb->ki_flags |= IOCB_WAITQ;
4237 kiocb->ki_flags &= ~IOCB_NOWAIT;
4238 kiocb->ki_waitq = wait;
4242 static inline int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
4244 if (likely(req->file->f_op->read_iter))
4245 return call_read_iter(req->file, &req->rw.kiocb, iter);
4246 else if (req->file->f_op->read)
4247 return loop_rw_iter(READ, req, iter);
4252 static bool need_read_all(struct io_kiocb *req)
4254 return req->flags & REQ_F_ISREG ||
4255 S_ISBLK(file_inode(req->file)->i_mode);
4258 static int io_rw_init_file(struct io_kiocb *req, fmode_t mode)
4260 struct kiocb *kiocb = &req->rw.kiocb;
4261 struct io_ring_ctx *ctx = req->ctx;
4262 struct file *file = req->file;
4265 if (unlikely(!file || !(file->f_mode & mode)))
4268 if (!io_req_ffs_set(req))
4269 req->flags |= io_file_get_flags(file) << REQ_F_SUPPORT_NOWAIT_BIT;
4271 kiocb->ki_flags = iocb_flags(file);
4272 ret = kiocb_set_rw_flags(kiocb, req->rw.flags);
4277 * If the file is marked O_NONBLOCK, still allow retry for it if it
4278 * supports async. Otherwise it's impossible to use O_NONBLOCK files
4279 * reliably. If not, or it IOCB_NOWAIT is set, don't retry.
4281 if ((kiocb->ki_flags & IOCB_NOWAIT) ||
4282 ((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req)))
4283 req->flags |= REQ_F_NOWAIT;
4285 if (ctx->flags & IORING_SETUP_IOPOLL) {
4286 if (!(kiocb->ki_flags & IOCB_DIRECT) || !file->f_op->iopoll)
4289 kiocb->private = NULL;
4290 kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE;
4291 kiocb->ki_complete = io_complete_rw_iopoll;
4292 req->iopoll_completed = 0;
4294 if (kiocb->ki_flags & IOCB_HIPRI)
4296 kiocb->ki_complete = io_complete_rw;
4302 static int io_read(struct io_kiocb *req, unsigned int issue_flags)
4304 struct io_rw_state __s, *s = &__s;
4305 struct iovec *iovec;
4306 struct kiocb *kiocb = &req->rw.kiocb;
4307 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4308 struct io_async_rw *rw;
4312 if (!req_has_async_data(req)) {
4313 ret = io_import_iovec(READ, req, &iovec, s, issue_flags);
4314 if (unlikely(ret < 0))
4318 * Safe and required to re-import if we're using provided
4319 * buffers, as we dropped the selected one before retry.
4321 if (req->flags & REQ_F_BUFFER_SELECT) {
4322 ret = io_import_iovec(READ, req, &iovec, s, issue_flags);
4323 if (unlikely(ret < 0))
4327 rw = req->async_data;
4330 * We come here from an earlier attempt, restore our state to
4331 * match in case it doesn't. It's cheap enough that we don't
4332 * need to make this conditional.
4334 iov_iter_restore(&s->iter, &s->iter_state);
4337 ret = io_rw_init_file(req, FMODE_READ);
4338 if (unlikely(ret)) {
4342 req->cqe.res = iov_iter_count(&s->iter);
4344 if (force_nonblock) {
4345 /* If the file doesn't support async, just async punt */
4346 if (unlikely(!io_file_supports_nowait(req))) {
4347 ret = io_setup_async_rw(req, iovec, s, true);
4348 return ret ?: -EAGAIN;
4350 kiocb->ki_flags |= IOCB_NOWAIT;
4352 /* Ensure we clear previously set non-block flag */
4353 kiocb->ki_flags &= ~IOCB_NOWAIT;
4356 ppos = io_kiocb_update_pos(req);
4358 ret = rw_verify_area(READ, req->file, ppos, req->cqe.res);
4359 if (unlikely(ret)) {
4364 ret = io_iter_do_read(req, &s->iter);
4366 if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
4367 req->flags &= ~REQ_F_REISSUE;
4368 /* if we can poll, just do that */
4369 if (req->opcode == IORING_OP_READ && file_can_poll(req->file))
4371 /* IOPOLL retry should happen for io-wq threads */
4372 if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
4374 /* no retry on NONBLOCK nor RWF_NOWAIT */
4375 if (req->flags & REQ_F_NOWAIT)
4378 } else if (ret == -EIOCBQUEUED) {
4380 } else if (ret == req->cqe.res || ret <= 0 || !force_nonblock ||
4381 (req->flags & REQ_F_NOWAIT) || !need_read_all(req)) {
4382 /* read all, failed, already did sync or don't want to retry */
4387 * Don't depend on the iter state matching what was consumed, or being
4388 * untouched in case of error. Restore it and we'll advance it
4389 * manually if we need to.
4391 iov_iter_restore(&s->iter, &s->iter_state);
4393 ret2 = io_setup_async_rw(req, iovec, s, true);
4398 rw = req->async_data;
4401 * Now use our persistent iterator and state, if we aren't already.
4402 * We've restored and mapped the iter to match.
4407 * We end up here because of a partial read, either from
4408 * above or inside this loop. Advance the iter by the bytes
4409 * that were consumed.
4411 iov_iter_advance(&s->iter, ret);
4412 if (!iov_iter_count(&s->iter))
4414 rw->bytes_done += ret;
4415 iov_iter_save_state(&s->iter, &s->iter_state);
4417 /* if we can retry, do so with the callbacks armed */
4418 if (!io_rw_should_retry(req)) {
4419 kiocb->ki_flags &= ~IOCB_WAITQ;
4424 * Now retry read with the IOCB_WAITQ parts set in the iocb. If
4425 * we get -EIOCBQUEUED, then we'll get a notification when the
4426 * desired page gets unlocked. We can also get a partial read
4427 * here, and if we do, then just retry at the new offset.
4429 ret = io_iter_do_read(req, &s->iter);
4430 if (ret == -EIOCBQUEUED)
4432 /* we got some bytes, but not all. retry. */
4433 kiocb->ki_flags &= ~IOCB_WAITQ;
4434 iov_iter_restore(&s->iter, &s->iter_state);
4437 kiocb_done(req, ret, issue_flags);
4439 /* it's faster to check here then delegate to kfree */
4445 static int io_write(struct io_kiocb *req, unsigned int issue_flags)
4447 struct io_rw_state __s, *s = &__s;
4448 struct iovec *iovec;
4449 struct kiocb *kiocb = &req->rw.kiocb;
4450 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
4454 if (!req_has_async_data(req)) {
4455 ret = io_import_iovec(WRITE, req, &iovec, s, issue_flags);
4456 if (unlikely(ret < 0))
4459 struct io_async_rw *rw = req->async_data;
4462 iov_iter_restore(&s->iter, &s->iter_state);
4465 ret = io_rw_init_file(req, FMODE_WRITE);
4466 if (unlikely(ret)) {
4470 req->cqe.res = iov_iter_count(&s->iter);
4472 if (force_nonblock) {
4473 /* If the file doesn't support async, just async punt */
4474 if (unlikely(!io_file_supports_nowait(req)))
4477 /* file path doesn't support NOWAIT for non-direct_IO */
4478 if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
4479 (req->flags & REQ_F_ISREG))
4482 kiocb->ki_flags |= IOCB_NOWAIT;
4484 /* Ensure we clear previously set non-block flag */
4485 kiocb->ki_flags &= ~IOCB_NOWAIT;
4488 ppos = io_kiocb_update_pos(req);
4490 ret = rw_verify_area(WRITE, req->file, ppos, req->cqe.res);
4495 * Open-code file_start_write here to grab freeze protection,
4496 * which will be released by another thread in
4497 * io_complete_rw(). Fool lockdep by telling it the lock got
4498 * released so that it doesn't complain about the held lock when
4499 * we return to userspace.
4501 if (req->flags & REQ_F_ISREG) {
4502 sb_start_write(file_inode(req->file)->i_sb);
4503 __sb_writers_release(file_inode(req->file)->i_sb,
4506 kiocb->ki_flags |= IOCB_WRITE;
4508 if (likely(req->file->f_op->write_iter))
4509 ret2 = call_write_iter(req->file, kiocb, &s->iter);
4510 else if (req->file->f_op->write)
4511 ret2 = loop_rw_iter(WRITE, req, &s->iter);
4515 if (req->flags & REQ_F_REISSUE) {
4516 req->flags &= ~REQ_F_REISSUE;
4521 * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
4522 * retry them without IOCB_NOWAIT.
4524 if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
4526 /* no retry on NONBLOCK nor RWF_NOWAIT */
4527 if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
4529 if (!force_nonblock || ret2 != -EAGAIN) {
4530 /* IOPOLL retry should happen for io-wq threads */
4531 if (ret2 == -EAGAIN && (req->ctx->flags & IORING_SETUP_IOPOLL))
4534 kiocb_done(req, ret2, issue_flags);
4537 iov_iter_restore(&s->iter, &s->iter_state);
4538 ret = io_setup_async_rw(req, iovec, s, false);
4539 return ret ?: -EAGAIN;
4542 /* it's reportedly faster than delegating the null check to kfree() */
4548 static int io_renameat_prep(struct io_kiocb *req,
4549 const struct io_uring_sqe *sqe)
4551 struct io_rename *ren = &req->rename;
4552 const char __user *oldf, *newf;
4554 if (sqe->buf_index || sqe->splice_fd_in)
4556 if (unlikely(req->flags & REQ_F_FIXED_FILE))
4559 ren->old_dfd = READ_ONCE(sqe->fd);
4560 oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
4561 newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4562 ren->new_dfd = READ_ONCE(sqe->len);
4563 ren->flags = READ_ONCE(sqe->rename_flags);
4565 ren->oldpath = getname(oldf);
4566 if (IS_ERR(ren->oldpath))
4567 return PTR_ERR(ren->oldpath);
4569 ren->newpath = getname(newf);
4570 if (IS_ERR(ren->newpath)) {
4571 putname(ren->oldpath);
4572 return PTR_ERR(ren->newpath);
4575 req->flags |= REQ_F_NEED_CLEANUP;
4579 static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
4581 struct io_rename *ren = &req->rename;
4584 if (issue_flags & IO_URING_F_NONBLOCK)
4587 ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
4588 ren->newpath, ren->flags);
4590 req->flags &= ~REQ_F_NEED_CLEANUP;
4591 io_req_complete(req, ret);
4595 static inline void __io_xattr_finish(struct io_kiocb *req)
4597 struct io_xattr *ix = &req->xattr;
4600 putname(ix->filename);
4602 kfree(ix->ctx.kname);
4603 kvfree(ix->ctx.kvalue);
4606 static void io_xattr_finish(struct io_kiocb *req, int ret)
4608 req->flags &= ~REQ_F_NEED_CLEANUP;
4610 __io_xattr_finish(req);
4611 io_req_complete(req, ret);
4614 static int __io_getxattr_prep(struct io_kiocb *req,
4615 const struct io_uring_sqe *sqe)
4617 struct io_xattr *ix = &req->xattr;
4618 const char __user *name;
4621 if (unlikely(req->flags & REQ_F_FIXED_FILE))
4624 ix->filename = NULL;
4625 ix->ctx.kvalue = NULL;
4626 name = u64_to_user_ptr(READ_ONCE(sqe->addr));
4627 ix->ctx.cvalue = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4628 ix->ctx.size = READ_ONCE(sqe->len);
4629 ix->ctx.flags = READ_ONCE(sqe->xattr_flags);
4634 ix->ctx.kname = kmalloc(sizeof(*ix->ctx.kname), GFP_KERNEL);
4638 ret = strncpy_from_user(ix->ctx.kname->name, name,
4639 sizeof(ix->ctx.kname->name));
4640 if (!ret || ret == sizeof(ix->ctx.kname->name))
4643 kfree(ix->ctx.kname);
4647 req->flags |= REQ_F_NEED_CLEANUP;
4651 static int io_fgetxattr_prep(struct io_kiocb *req,
4652 const struct io_uring_sqe *sqe)
4654 return __io_getxattr_prep(req, sqe);
4657 static int io_getxattr_prep(struct io_kiocb *req,
4658 const struct io_uring_sqe *sqe)
4660 struct io_xattr *ix = &req->xattr;
4661 const char __user *path;
4664 ret = __io_getxattr_prep(req, sqe);
4668 path = u64_to_user_ptr(READ_ONCE(sqe->addr3));
4670 ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);
4671 if (IS_ERR(ix->filename)) {
4672 ret = PTR_ERR(ix->filename);
4673 ix->filename = NULL;
4679 static int io_fgetxattr(struct io_kiocb *req, unsigned int issue_flags)
4681 struct io_xattr *ix = &req->xattr;
4684 if (issue_flags & IO_URING_F_NONBLOCK)
4687 ret = do_getxattr(mnt_user_ns(req->file->f_path.mnt),
4688 req->file->f_path.dentry,
4691 io_xattr_finish(req, ret);
4695 static int io_getxattr(struct io_kiocb *req, unsigned int issue_flags)
4697 struct io_xattr *ix = &req->xattr;
4698 unsigned int lookup_flags = LOOKUP_FOLLOW;
4702 if (issue_flags & IO_URING_F_NONBLOCK)
4706 ret = filename_lookup(AT_FDCWD, ix->filename, lookup_flags, &path, NULL);
4708 ret = do_getxattr(mnt_user_ns(path.mnt),
4713 if (retry_estale(ret, lookup_flags)) {
4714 lookup_flags |= LOOKUP_REVAL;
4719 io_xattr_finish(req, ret);
4723 static int __io_setxattr_prep(struct io_kiocb *req,
4724 const struct io_uring_sqe *sqe)
4726 struct io_xattr *ix = &req->xattr;
4727 const char __user *name;
4730 if (unlikely(req->flags & REQ_F_FIXED_FILE))
4733 ix->filename = NULL;
4734 name = u64_to_user_ptr(READ_ONCE(sqe->addr));
4735 ix->ctx.cvalue = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4736 ix->ctx.kvalue = NULL;
4737 ix->ctx.size = READ_ONCE(sqe->len);
4738 ix->ctx.flags = READ_ONCE(sqe->xattr_flags);
4740 ix->ctx.kname = kmalloc(sizeof(*ix->ctx.kname), GFP_KERNEL);
4744 ret = setxattr_copy(name, &ix->ctx);
4746 kfree(ix->ctx.kname);
4750 req->flags |= REQ_F_NEED_CLEANUP;
4754 static int io_setxattr_prep(struct io_kiocb *req,
4755 const struct io_uring_sqe *sqe)
4757 struct io_xattr *ix = &req->xattr;
4758 const char __user *path;
4761 ret = __io_setxattr_prep(req, sqe);
4765 path = u64_to_user_ptr(READ_ONCE(sqe->addr3));
4767 ix->filename = getname_flags(path, LOOKUP_FOLLOW, NULL);
4768 if (IS_ERR(ix->filename)) {
4769 ret = PTR_ERR(ix->filename);
4770 ix->filename = NULL;
4776 static int io_fsetxattr_prep(struct io_kiocb *req,
4777 const struct io_uring_sqe *sqe)
4779 return __io_setxattr_prep(req, sqe);
4782 static int __io_setxattr(struct io_kiocb *req, unsigned int issue_flags,
4785 struct io_xattr *ix = &req->xattr;
4788 ret = mnt_want_write(path->mnt);
4790 ret = do_setxattr(mnt_user_ns(path->mnt), path->dentry, &ix->ctx);
4791 mnt_drop_write(path->mnt);
4797 static int io_fsetxattr(struct io_kiocb *req, unsigned int issue_flags)
4801 if (issue_flags & IO_URING_F_NONBLOCK)
4804 ret = __io_setxattr(req, issue_flags, &req->file->f_path);
4805 io_xattr_finish(req, ret);
4810 static int io_setxattr(struct io_kiocb *req, unsigned int issue_flags)
4812 struct io_xattr *ix = &req->xattr;
4813 unsigned int lookup_flags = LOOKUP_FOLLOW;
4817 if (issue_flags & IO_URING_F_NONBLOCK)
4821 ret = filename_lookup(AT_FDCWD, ix->filename, lookup_flags, &path, NULL);
4823 ret = __io_setxattr(req, issue_flags, &path);
4825 if (retry_estale(ret, lookup_flags)) {
4826 lookup_flags |= LOOKUP_REVAL;
4831 io_xattr_finish(req, ret);
4835 static int io_unlinkat_prep(struct io_kiocb *req,
4836 const struct io_uring_sqe *sqe)
4838 struct io_unlink *un = &req->unlink;
4839 const char __user *fname;
4841 if (sqe->off || sqe->len || sqe->buf_index || sqe->splice_fd_in)
4843 if (unlikely(req->flags & REQ_F_FIXED_FILE))
4846 un->dfd = READ_ONCE(sqe->fd);
4848 un->flags = READ_ONCE(sqe->unlink_flags);
4849 if (un->flags & ~AT_REMOVEDIR)
4852 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
4853 un->filename = getname(fname);
4854 if (IS_ERR(un->filename))
4855 return PTR_ERR(un->filename);
4857 req->flags |= REQ_F_NEED_CLEANUP;
4861 static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
4863 struct io_unlink *un = &req->unlink;
4866 if (issue_flags & IO_URING_F_NONBLOCK)
4869 if (un->flags & AT_REMOVEDIR)
4870 ret = do_rmdir(un->dfd, un->filename);
4872 ret = do_unlinkat(un->dfd, un->filename);
4874 req->flags &= ~REQ_F_NEED_CLEANUP;
4875 io_req_complete(req, ret);
4879 static int io_mkdirat_prep(struct io_kiocb *req,
4880 const struct io_uring_sqe *sqe)
4882 struct io_mkdir *mkd = &req->mkdir;
4883 const char __user *fname;
4885 if (sqe->off || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
4887 if (unlikely(req->flags & REQ_F_FIXED_FILE))
4890 mkd->dfd = READ_ONCE(sqe->fd);
4891 mkd->mode = READ_ONCE(sqe->len);
4893 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
4894 mkd->filename = getname(fname);
4895 if (IS_ERR(mkd->filename))
4896 return PTR_ERR(mkd->filename);
4898 req->flags |= REQ_F_NEED_CLEANUP;
4902 static int io_mkdirat(struct io_kiocb *req, unsigned int issue_flags)
4904 struct io_mkdir *mkd = &req->mkdir;
4907 if (issue_flags & IO_URING_F_NONBLOCK)
4910 ret = do_mkdirat(mkd->dfd, mkd->filename, mkd->mode);
4912 req->flags &= ~REQ_F_NEED_CLEANUP;
4913 io_req_complete(req, ret);
4917 static int io_symlinkat_prep(struct io_kiocb *req,
4918 const struct io_uring_sqe *sqe)
4920 struct io_symlink *sl = &req->symlink;
4921 const char __user *oldpath, *newpath;
4923 if (sqe->len || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
4925 if (unlikely(req->flags & REQ_F_FIXED_FILE))
4928 sl->new_dfd = READ_ONCE(sqe->fd);
4929 oldpath = u64_to_user_ptr(READ_ONCE(sqe->addr));
4930 newpath = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4932 sl->oldpath = getname(oldpath);
4933 if (IS_ERR(sl->oldpath))
4934 return PTR_ERR(sl->oldpath);
4936 sl->newpath = getname(newpath);
4937 if (IS_ERR(sl->newpath)) {
4938 putname(sl->oldpath);
4939 return PTR_ERR(sl->newpath);
4942 req->flags |= REQ_F_NEED_CLEANUP;
4946 static int io_symlinkat(struct io_kiocb *req, unsigned int issue_flags)
4948 struct io_symlink *sl = &req->symlink;
4951 if (issue_flags & IO_URING_F_NONBLOCK)
4954 ret = do_symlinkat(sl->oldpath, sl->new_dfd, sl->newpath);
4956 req->flags &= ~REQ_F_NEED_CLEANUP;
4957 io_req_complete(req, ret);
4961 static int io_linkat_prep(struct io_kiocb *req,
4962 const struct io_uring_sqe *sqe)
4964 struct io_hardlink *lnk = &req->hardlink;
4965 const char __user *oldf, *newf;
4967 if (sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
4969 if (unlikely(req->flags & REQ_F_FIXED_FILE))
4972 lnk->old_dfd = READ_ONCE(sqe->fd);
4973 lnk->new_dfd = READ_ONCE(sqe->len);
4974 oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
4975 newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
4976 lnk->flags = READ_ONCE(sqe->hardlink_flags);
4978 lnk->oldpath = getname(oldf);
4979 if (IS_ERR(lnk->oldpath))
4980 return PTR_ERR(lnk->oldpath);
4982 lnk->newpath = getname(newf);
4983 if (IS_ERR(lnk->newpath)) {
4984 putname(lnk->oldpath);
4985 return PTR_ERR(lnk->newpath);
4988 req->flags |= REQ_F_NEED_CLEANUP;
4992 static int io_linkat(struct io_kiocb *req, unsigned int issue_flags)
4994 struct io_hardlink *lnk = &req->hardlink;
4997 if (issue_flags & IO_URING_F_NONBLOCK)
5000 ret = do_linkat(lnk->old_dfd, lnk->oldpath, lnk->new_dfd,
5001 lnk->newpath, lnk->flags);
5003 req->flags &= ~REQ_F_NEED_CLEANUP;
5004 io_req_complete(req, ret);
5008 static void io_uring_cmd_work(struct io_kiocb *req, bool *locked)
5010 req->uring_cmd.task_work_cb(&req->uring_cmd);
5013 void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
5014 void (*task_work_cb)(struct io_uring_cmd *))
5016 struct io_kiocb *req = container_of(ioucmd, struct io_kiocb, uring_cmd);
5018 req->uring_cmd.task_work_cb = task_work_cb;
5019 req->io_task_work.func = io_uring_cmd_work;
5020 io_req_task_work_add(req);
5022 EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task);
5024 static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
5025 u64 extra1, u64 extra2)
5027 req->extra1 = extra1;
5028 req->extra2 = extra2;
5029 req->flags |= REQ_F_CQE32_INIT;
5033 * Called by consumers of io_uring_cmd, if they originally returned
5034 * -EIOCBQUEUED upon receiving the command.
5036 void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2)
5038 struct io_kiocb *req = container_of(ioucmd, struct io_kiocb, uring_cmd);
5043 if (req->ctx->flags & IORING_SETUP_CQE32)
5044 io_req_set_cqe32_extra(req, res2, 0);
5045 io_req_complete(req, ret);
5047 EXPORT_SYMBOL_GPL(io_uring_cmd_done);
5049 static int io_uring_cmd_prep_async(struct io_kiocb *req)
5053 cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128);
5055 memcpy(req->async_data, req->uring_cmd.cmd, cmd_size);
5059 static int io_uring_cmd_prep(struct io_kiocb *req,
5060 const struct io_uring_sqe *sqe)
5062 struct io_uring_cmd *ioucmd = &req->uring_cmd;
5066 ioucmd->cmd = sqe->cmd;
5067 ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
5071 static int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
5073 struct io_uring_cmd *ioucmd = &req->uring_cmd;
5074 struct io_ring_ctx *ctx = req->ctx;
5075 struct file *file = req->file;
5078 if (!req->file->f_op->uring_cmd)
5081 if (ctx->flags & IORING_SETUP_SQE128)
5082 issue_flags |= IO_URING_F_SQE128;
5083 if (ctx->flags & IORING_SETUP_CQE32)
5084 issue_flags |= IO_URING_F_CQE32;
5085 if (ctx->flags & IORING_SETUP_IOPOLL)
5086 issue_flags |= IO_URING_F_IOPOLL;
5088 if (req_has_async_data(req))
5089 ioucmd->cmd = req->async_data;
5091 ret = file->f_op->uring_cmd(ioucmd, issue_flags);
5092 if (ret == -EAGAIN) {
5093 if (!req_has_async_data(req)) {
5094 if (io_alloc_async_data(req))
5096 io_uring_cmd_prep_async(req);
5101 if (ret != -EIOCBQUEUED)
5102 io_uring_cmd_done(ioucmd, ret, 0);
5106 static int __io_splice_prep(struct io_kiocb *req,
5107 const struct io_uring_sqe *sqe)
5109 struct io_splice *sp = &req->splice;
5110 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
5112 sp->len = READ_ONCE(sqe->len);
5113 sp->flags = READ_ONCE(sqe->splice_flags);
5114 if (unlikely(sp->flags & ~valid_flags))
5116 sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in);
5120 static int io_tee_prep(struct io_kiocb *req,
5121 const struct io_uring_sqe *sqe)
5123 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
5125 return __io_splice_prep(req, sqe);
5128 static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
5130 struct io_splice *sp = &req->splice;
5131 struct file *out = sp->file_out;
5132 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
5136 if (issue_flags & IO_URING_F_NONBLOCK)
5139 if (sp->flags & SPLICE_F_FD_IN_FIXED)
5140 in = io_file_get_fixed(req, sp->splice_fd_in, issue_flags);
5142 in = io_file_get_normal(req, sp->splice_fd_in);
5149 ret = do_tee(in, out, sp->len, flags);
5151 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
5156 __io_req_complete(req, 0, ret, 0);
5160 static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5162 struct io_splice *sp = &req->splice;
5164 sp->off_in = READ_ONCE(sqe->splice_off_in);
5165 sp->off_out = READ_ONCE(sqe->off);
5166 return __io_splice_prep(req, sqe);
5169 static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
5171 struct io_splice *sp = &req->splice;
5172 struct file *out = sp->file_out;
5173 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
5174 loff_t *poff_in, *poff_out;
5178 if (issue_flags & IO_URING_F_NONBLOCK)
5181 if (sp->flags & SPLICE_F_FD_IN_FIXED)
5182 in = io_file_get_fixed(req, sp->splice_fd_in, issue_flags);
5184 in = io_file_get_normal(req, sp->splice_fd_in);
5190 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
5191 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
5194 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
5196 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
5201 __io_req_complete(req, 0, ret, 0);
5205 static int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5211 * IORING_OP_NOP just posts a completion event, nothing else.
5213 static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
5215 __io_req_complete(req, issue_flags, 0, 0);
5219 static int io_msg_ring_prep(struct io_kiocb *req,
5220 const struct io_uring_sqe *sqe)
5222 if (unlikely(sqe->addr || sqe->rw_flags || sqe->splice_fd_in ||
5223 sqe->buf_index || sqe->personality))
5226 req->msg.user_data = READ_ONCE(sqe->off);
5227 req->msg.len = READ_ONCE(sqe->len);
5231 static int io_msg_ring(struct io_kiocb *req, unsigned int issue_flags)
5233 struct io_ring_ctx *target_ctx;
5234 struct io_msg *msg = &req->msg;
5239 if (req->file->f_op != &io_uring_fops)
5243 target_ctx = req->file->private_data;
5245 spin_lock(&target_ctx->completion_lock);
5246 filled = io_fill_cqe_aux(target_ctx, msg->user_data, msg->len, 0);
5247 io_commit_cqring(target_ctx);
5248 spin_unlock(&target_ctx->completion_lock);
5251 io_cqring_ev_posted(target_ctx);
5258 __io_req_complete(req, issue_flags, ret, 0);
5259 /* put file to avoid an attempt to IOPOLL the req */
5260 io_put_file(req->file);
5265 static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5267 if (unlikely(sqe->addr || sqe->buf_index || sqe->splice_fd_in))
5270 req->sync.flags = READ_ONCE(sqe->fsync_flags);
5271 if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
5274 req->sync.off = READ_ONCE(sqe->off);
5275 req->sync.len = READ_ONCE(sqe->len);
5279 static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
5281 loff_t end = req->sync.off + req->sync.len;
5284 /* fsync always requires a blocking context */
5285 if (issue_flags & IO_URING_F_NONBLOCK)
5288 ret = vfs_fsync_range(req->file, req->sync.off,
5289 end > 0 ? end : LLONG_MAX,
5290 req->sync.flags & IORING_FSYNC_DATASYNC);
5291 io_req_complete(req, ret);
5295 static int io_fallocate_prep(struct io_kiocb *req,
5296 const struct io_uring_sqe *sqe)
5298 if (sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
5301 req->sync.off = READ_ONCE(sqe->off);
5302 req->sync.len = READ_ONCE(sqe->addr);
5303 req->sync.mode = READ_ONCE(sqe->len);
5307 static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
5311 /* fallocate always requiring blocking context */
5312 if (issue_flags & IO_URING_F_NONBLOCK)
5314 ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
5317 fsnotify_modify(req->file);
5318 io_req_complete(req, ret);
5322 static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5324 const char __user *fname;
5327 if (unlikely(sqe->buf_index))
5329 if (unlikely(req->flags & REQ_F_FIXED_FILE))
5332 /* open.how should be already initialised */
5333 if (!(req->open.how.flags & O_PATH) && force_o_largefile())
5334 req->open.how.flags |= O_LARGEFILE;
5336 req->open.dfd = READ_ONCE(sqe->fd);
5337 fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
5338 req->open.filename = getname(fname);
5339 if (IS_ERR(req->open.filename)) {
5340 ret = PTR_ERR(req->open.filename);
5341 req->open.filename = NULL;
5345 req->open.file_slot = READ_ONCE(sqe->file_index);
5346 if (req->open.file_slot && (req->open.how.flags & O_CLOEXEC))
5349 req->open.nofile = rlimit(RLIMIT_NOFILE);
5350 req->flags |= REQ_F_NEED_CLEANUP;
5354 static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5356 u64 mode = READ_ONCE(sqe->len);
5357 u64 flags = READ_ONCE(sqe->open_flags);
5359 req->open.how = build_open_how(flags, mode);
5360 return __io_openat_prep(req, sqe);
5363 static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5365 struct open_how __user *how;
5369 how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
5370 len = READ_ONCE(sqe->len);
5371 if (len < OPEN_HOW_SIZE_VER0)
5374 ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
5379 return __io_openat_prep(req, sqe);
5382 static int io_file_bitmap_get(struct io_ring_ctx *ctx)
5384 struct io_file_table *table = &ctx->file_table;
5385 unsigned long nr = ctx->nr_user_files;
5389 ret = find_next_zero_bit(table->bitmap, nr, table->alloc_hint);
5393 if (!table->alloc_hint)
5396 nr = table->alloc_hint;
5397 table->alloc_hint = 0;
5404 * Note when io_fixed_fd_install() returns error value, it will ensure
5405 * fput() is called correspondingly.
5407 static int io_fixed_fd_install(struct io_kiocb *req, unsigned int issue_flags,
5408 struct file *file, unsigned int file_slot)
5410 bool alloc_slot = file_slot == IORING_FILE_INDEX_ALLOC;
5411 struct io_ring_ctx *ctx = req->ctx;
5414 io_ring_submit_lock(ctx, issue_flags);
5417 ret = io_file_bitmap_get(ctx);
5418 if (unlikely(ret < 0))
5425 ret = io_install_fixed_file(req, file, issue_flags, file_slot);
5426 if (!ret && alloc_slot)
5429 io_ring_submit_unlock(ctx, issue_flags);
5430 if (unlikely(ret < 0))
5435 static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
5437 struct open_flags op;
5439 bool resolve_nonblock, nonblock_set;
5440 bool fixed = !!req->open.file_slot;
5443 ret = build_open_flags(&req->open.how, &op);
5446 nonblock_set = op.open_flag & O_NONBLOCK;
5447 resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
5448 if (issue_flags & IO_URING_F_NONBLOCK) {
5450 * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
5451 * it'll always -EAGAIN
5453 if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
5455 op.lookup_flags |= LOOKUP_CACHED;
5456 op.open_flag |= O_NONBLOCK;
5460 ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
5465 file = do_filp_open(req->open.dfd, req->open.filename, &op);
5468 * We could hang on to this 'fd' on retrying, but seems like
5469 * marginal gain for something that is now known to be a slower
5470 * path. So just put it, and we'll get a new one when we retry.
5475 ret = PTR_ERR(file);
5476 /* only retry if RESOLVE_CACHED wasn't already set by application */
5477 if (ret == -EAGAIN &&
5478 (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)))
5483 if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
5484 file->f_flags &= ~O_NONBLOCK;
5485 fsnotify_open(file);
5488 fd_install(ret, file);
5490 ret = io_fixed_fd_install(req, issue_flags, file,
5491 req->open.file_slot);
5493 putname(req->open.filename);
5494 req->flags &= ~REQ_F_NEED_CLEANUP;
5497 __io_req_complete(req, issue_flags, ret, 0);
5501 static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
5503 return io_openat2(req, issue_flags);
5506 static int io_remove_buffers_prep(struct io_kiocb *req,
5507 const struct io_uring_sqe *sqe)
5509 struct io_provide_buf *p = &req->pbuf;
5512 if (sqe->rw_flags || sqe->addr || sqe->len || sqe->off ||
5516 tmp = READ_ONCE(sqe->fd);
5517 if (!tmp || tmp > USHRT_MAX)
5520 memset(p, 0, sizeof(*p));
5522 p->bgid = READ_ONCE(sqe->buf_group);
5526 static int __io_remove_buffers(struct io_ring_ctx *ctx,
5527 struct io_buffer_list *bl, unsigned nbufs)
5531 /* shouldn't happen */
5535 if (bl->buf_nr_pages) {
5538 i = bl->buf_ring->tail - bl->head;
5539 for (j = 0; j < bl->buf_nr_pages; j++)
5540 unpin_user_page(bl->buf_pages[j]);
5541 kvfree(bl->buf_pages);
5542 bl->buf_pages = NULL;
5543 bl->buf_nr_pages = 0;
5544 /* make sure it's seen as empty */
5545 INIT_LIST_HEAD(&bl->buf_list);
5549 /* the head kbuf is the list itself */
5550 while (!list_empty(&bl->buf_list)) {
5551 struct io_buffer *nxt;
5553 nxt = list_first_entry(&bl->buf_list, struct io_buffer, list);
5554 list_del(&nxt->list);
5564 static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
5566 struct io_provide_buf *p = &req->pbuf;
5567 struct io_ring_ctx *ctx = req->ctx;
5568 struct io_buffer_list *bl;
5571 io_ring_submit_lock(ctx, issue_flags);
5574 bl = io_buffer_get_list(ctx, p->bgid);
5577 /* can't use provide/remove buffers command on mapped buffers */
5578 if (!bl->buf_nr_pages)
5579 ret = __io_remove_buffers(ctx, bl, p->nbufs);
5584 /* complete before unlock, IOPOLL may need the lock */
5585 __io_req_complete(req, issue_flags, ret, 0);
5586 io_ring_submit_unlock(ctx, issue_flags);
5590 static int io_provide_buffers_prep(struct io_kiocb *req,
5591 const struct io_uring_sqe *sqe)
5593 unsigned long size, tmp_check;
5594 struct io_provide_buf *p = &req->pbuf;
5597 if (sqe->rw_flags || sqe->splice_fd_in)
5600 tmp = READ_ONCE(sqe->fd);
5601 if (!tmp || tmp > USHRT_MAX)
5604 p->addr = READ_ONCE(sqe->addr);
5605 p->len = READ_ONCE(sqe->len);
5607 if (check_mul_overflow((unsigned long)p->len, (unsigned long)p->nbufs,
5610 if (check_add_overflow((unsigned long)p->addr, size, &tmp_check))
5613 size = (unsigned long)p->len * p->nbufs;
5614 if (!access_ok(u64_to_user_ptr(p->addr), size))
5617 p->bgid = READ_ONCE(sqe->buf_group);
5618 tmp = READ_ONCE(sqe->off);
5619 if (tmp > USHRT_MAX)
5625 static int io_refill_buffer_cache(struct io_ring_ctx *ctx)
5627 struct io_buffer *buf;
5632 * Completions that don't happen inline (eg not under uring_lock) will
5633 * add to ->io_buffers_comp. If we don't have any free buffers, check
5634 * the completion list and splice those entries first.
5636 if (!list_empty_careful(&ctx->io_buffers_comp)) {
5637 spin_lock(&ctx->completion_lock);
5638 if (!list_empty(&ctx->io_buffers_comp)) {
5639 list_splice_init(&ctx->io_buffers_comp,
5640 &ctx->io_buffers_cache);
5641 spin_unlock(&ctx->completion_lock);
5644 spin_unlock(&ctx->completion_lock);
5648 * No free buffers and no completion entries either. Allocate a new
5649 * page worth of buffer entries and add those to our freelist.
5651 page = alloc_page(GFP_KERNEL_ACCOUNT);
5655 list_add(&page->lru, &ctx->io_buffers_pages);
5657 buf = page_address(page);
5658 bufs_in_page = PAGE_SIZE / sizeof(*buf);
5659 while (bufs_in_page) {
5660 list_add_tail(&buf->list, &ctx->io_buffers_cache);
5668 static int io_add_buffers(struct io_ring_ctx *ctx, struct io_provide_buf *pbuf,
5669 struct io_buffer_list *bl)
5671 struct io_buffer *buf;
5672 u64 addr = pbuf->addr;
5673 int i, bid = pbuf->bid;
5675 for (i = 0; i < pbuf->nbufs; i++) {
5676 if (list_empty(&ctx->io_buffers_cache) &&
5677 io_refill_buffer_cache(ctx))
5679 buf = list_first_entry(&ctx->io_buffers_cache, struct io_buffer,
5681 list_move_tail(&buf->list, &bl->buf_list);
5683 buf->len = min_t(__u32, pbuf->len, MAX_RW_COUNT);
5685 buf->bgid = pbuf->bgid;
5691 return i ? 0 : -ENOMEM;
5694 static __cold int io_init_bl_list(struct io_ring_ctx *ctx)
5698 ctx->io_bl = kcalloc(BGID_ARRAY, sizeof(struct io_buffer_list),
5703 for (i = 0; i < BGID_ARRAY; i++) {
5704 INIT_LIST_HEAD(&ctx->io_bl[i].buf_list);
5705 ctx->io_bl[i].bgid = i;
5711 static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
5713 struct io_provide_buf *p = &req->pbuf;
5714 struct io_ring_ctx *ctx = req->ctx;
5715 struct io_buffer_list *bl;
5718 io_ring_submit_lock(ctx, issue_flags);
5720 if (unlikely(p->bgid < BGID_ARRAY && !ctx->io_bl)) {
5721 ret = io_init_bl_list(ctx);
5726 bl = io_buffer_get_list(ctx, p->bgid);
5727 if (unlikely(!bl)) {
5728 bl = kzalloc(sizeof(*bl), GFP_KERNEL);
5733 INIT_LIST_HEAD(&bl->buf_list);
5734 ret = io_buffer_add_list(ctx, bl, p->bgid);
5740 /* can't add buffers via this command for a mapped buffer ring */
5741 if (bl->buf_nr_pages) {
5746 ret = io_add_buffers(ctx, p, bl);
5750 /* complete before unlock, IOPOLL may need the lock */
5751 __io_req_complete(req, issue_flags, ret, 0);
5752 io_ring_submit_unlock(ctx, issue_flags);
5756 static int io_epoll_ctl_prep(struct io_kiocb *req,
5757 const struct io_uring_sqe *sqe)
5759 #if defined(CONFIG_EPOLL)
5760 if (sqe->buf_index || sqe->splice_fd_in)
5763 req->epoll.epfd = READ_ONCE(sqe->fd);
5764 req->epoll.op = READ_ONCE(sqe->len);
5765 req->epoll.fd = READ_ONCE(sqe->off);
5767 if (ep_op_has_event(req->epoll.op)) {
5768 struct epoll_event __user *ev;
5770 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
5771 if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
5781 static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
5783 #if defined(CONFIG_EPOLL)
5784 struct io_epoll *ie = &req->epoll;
5786 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
5788 ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
5789 if (force_nonblock && ret == -EAGAIN)
5794 __io_req_complete(req, issue_flags, ret, 0);
5801 static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5803 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
5804 if (sqe->buf_index || sqe->off || sqe->splice_fd_in)
5807 req->madvise.addr = READ_ONCE(sqe->addr);
5808 req->madvise.len = READ_ONCE(sqe->len);
5809 req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
5816 static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
5818 #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
5819 struct io_madvise *ma = &req->madvise;
5822 if (issue_flags & IO_URING_F_NONBLOCK)
5825 ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
5826 io_req_complete(req, ret);
5833 static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5835 if (sqe->buf_index || sqe->addr || sqe->splice_fd_in)
5838 req->fadvise.offset = READ_ONCE(sqe->off);
5839 req->fadvise.len = READ_ONCE(sqe->len);
5840 req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
5844 static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
5846 struct io_fadvise *fa = &req->fadvise;
5849 if (issue_flags & IO_URING_F_NONBLOCK) {
5850 switch (fa->advice) {
5851 case POSIX_FADV_NORMAL:
5852 case POSIX_FADV_RANDOM:
5853 case POSIX_FADV_SEQUENTIAL:
5860 ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
5863 __io_req_complete(req, issue_flags, ret, 0);
5867 static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5869 const char __user *path;
5871 if (sqe->buf_index || sqe->splice_fd_in)
5873 if (req->flags & REQ_F_FIXED_FILE)
5876 req->statx.dfd = READ_ONCE(sqe->fd);
5877 req->statx.mask = READ_ONCE(sqe->len);
5878 path = u64_to_user_ptr(READ_ONCE(sqe->addr));
5879 req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
5880 req->statx.flags = READ_ONCE(sqe->statx_flags);
5882 req->statx.filename = getname_flags(path,
5883 getname_statx_lookup_flags(req->statx.flags),
5886 if (IS_ERR(req->statx.filename)) {
5887 int ret = PTR_ERR(req->statx.filename);
5889 req->statx.filename = NULL;
5893 req->flags |= REQ_F_NEED_CLEANUP;
5897 static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
5899 struct io_statx *ctx = &req->statx;
5902 if (issue_flags & IO_URING_F_NONBLOCK)
5905 ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
5907 io_req_complete(req, ret);
5911 static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5913 if (sqe->off || sqe->addr || sqe->len || sqe->rw_flags || sqe->buf_index)
5915 if (req->flags & REQ_F_FIXED_FILE)
5918 req->close.fd = READ_ONCE(sqe->fd);
5919 req->close.file_slot = READ_ONCE(sqe->file_index);
5920 if (req->close.file_slot && req->close.fd)
5926 static int io_close(struct io_kiocb *req, unsigned int issue_flags)
5928 struct files_struct *files = current->files;
5929 struct io_close *close = &req->close;
5930 struct fdtable *fdt;
5934 if (req->close.file_slot) {
5935 ret = io_close_fixed(req, issue_flags);
5939 spin_lock(&files->file_lock);
5940 fdt = files_fdtable(files);
5941 if (close->fd >= fdt->max_fds) {
5942 spin_unlock(&files->file_lock);
5945 file = rcu_dereference_protected(fdt->fd[close->fd],
5946 lockdep_is_held(&files->file_lock));
5947 if (!file || file->f_op == &io_uring_fops) {
5948 spin_unlock(&files->file_lock);
5952 /* if the file has a flush method, be safe and punt to async */
5953 if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
5954 spin_unlock(&files->file_lock);
5958 file = __close_fd_get_file(close->fd);
5959 spin_unlock(&files->file_lock);
5963 /* No ->flush() or already async, safely close from here */
5964 ret = filp_close(file, current->files);
5968 __io_req_complete(req, issue_flags, ret, 0);
5972 static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
5974 if (unlikely(sqe->addr || sqe->buf_index || sqe->splice_fd_in))
5977 req->sync.off = READ_ONCE(sqe->off);
5978 req->sync.len = READ_ONCE(sqe->len);
5979 req->sync.flags = READ_ONCE(sqe->sync_range_flags);
5983 static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
5987 /* sync_file_range always requires a blocking context */
5988 if (issue_flags & IO_URING_F_NONBLOCK)
5991 ret = sync_file_range(req->file, req->sync.off, req->sync.len,
5993 io_req_complete(req, ret);
5997 #if defined(CONFIG_NET)
5998 static int io_shutdown_prep(struct io_kiocb *req,
5999 const struct io_uring_sqe *sqe)
6001 if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
6002 sqe->buf_index || sqe->splice_fd_in))
6005 req->shutdown.how = READ_ONCE(sqe->len);
6009 static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
6011 struct socket *sock;
6014 if (issue_flags & IO_URING_F_NONBLOCK)
6017 sock = sock_from_file(req->file);
6018 if (unlikely(!sock))
6021 ret = __sys_shutdown_sock(sock, req->shutdown.how);
6022 io_req_complete(req, ret);
6026 static bool io_net_retry(struct socket *sock, int flags)
6028 if (!(flags & MSG_WAITALL))
6030 return sock->type == SOCK_STREAM || sock->type == SOCK_SEQPACKET;
6033 static int io_setup_async_msg(struct io_kiocb *req,
6034 struct io_async_msghdr *kmsg)
6036 struct io_async_msghdr *async_msg = req->async_data;
6040 if (io_alloc_async_data(req)) {
6041 kfree(kmsg->free_iov);
6044 async_msg = req->async_data;
6045 req->flags |= REQ_F_NEED_CLEANUP;
6046 memcpy(async_msg, kmsg, sizeof(*kmsg));
6047 async_msg->msg.msg_name = &async_msg->addr;
6048 /* if were using fast_iov, set it to the new one */
6049 if (!async_msg->free_iov)
6050 async_msg->msg.msg_iter.iov = async_msg->fast_iov;
6055 static int io_sendmsg_copy_hdr(struct io_kiocb *req,
6056 struct io_async_msghdr *iomsg)
6058 iomsg->msg.msg_name = &iomsg->addr;
6059 iomsg->free_iov = iomsg->fast_iov;
6060 return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
6061 req->sr_msg.msg_flags, &iomsg->free_iov);
6064 static int io_sendmsg_prep_async(struct io_kiocb *req)
6068 ret = io_sendmsg_copy_hdr(req, req->async_data);
6070 req->flags |= REQ_F_NEED_CLEANUP;
6074 static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
6076 struct io_sr_msg *sr = &req->sr_msg;
6078 if (unlikely(sqe->file_index))
6080 if (unlikely(sqe->addr2 || sqe->file_index))
6083 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
6084 sr->len = READ_ONCE(sqe->len);
6085 sr->flags = READ_ONCE(sqe->addr2);
6086 if (sr->flags & ~IORING_RECVSEND_POLL_FIRST)
6088 sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
6089 if (sr->msg_flags & MSG_DONTWAIT)
6090 req->flags |= REQ_F_NOWAIT;
6092 #ifdef CONFIG_COMPAT
6093 if (req->ctx->compat)
6094 sr->msg_flags |= MSG_CMSG_COMPAT;
6100 static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
6102 struct io_async_msghdr iomsg, *kmsg;
6103 struct io_sr_msg *sr = &req->sr_msg;
6104 struct socket *sock;
6109 sock = sock_from_file(req->file);
6110 if (unlikely(!sock))
6113 if (req_has_async_data(req)) {
6114 kmsg = req->async_data;
6116 ret = io_sendmsg_copy_hdr(req, &iomsg);
6122 if (!(req->flags & REQ_F_POLLED) &&
6123 (sr->flags & IORING_RECVSEND_POLL_FIRST))
6124 return io_setup_async_msg(req, kmsg);
6126 flags = sr->msg_flags;
6127 if (issue_flags & IO_URING_F_NONBLOCK)
6128 flags |= MSG_DONTWAIT;
6129 if (flags & MSG_WAITALL)
6130 min_ret = iov_iter_count(&kmsg->msg.msg_iter);
6132 ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
6134 if (ret < min_ret) {
6135 if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
6136 return io_setup_async_msg(req, kmsg);
6137 if (ret == -ERESTARTSYS)
6139 if (ret > 0 && io_net_retry(sock, flags)) {
6141 req->flags |= REQ_F_PARTIAL_IO;
6142 return io_setup_async_msg(req, kmsg);
6146 /* fast path, check for non-NULL to avoid function call */
6148 kfree(kmsg->free_iov);
6149 req->flags &= ~REQ_F_NEED_CLEANUP;
6152 else if (sr->done_io)
6154 __io_req_complete(req, issue_flags, ret, 0);
6158 static int io_send(struct io_kiocb *req, unsigned int issue_flags)
6160 struct io_sr_msg *sr = &req->sr_msg;
6163 struct socket *sock;
6168 if (!(req->flags & REQ_F_POLLED) &&
6169 (sr->flags & IORING_RECVSEND_POLL_FIRST))
6172 sock = sock_from_file(req->file);
6173 if (unlikely(!sock))
6176 ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
6180 msg.msg_name = NULL;
6181 msg.msg_control = NULL;
6182 msg.msg_controllen = 0;
6183 msg.msg_namelen = 0;
6185 flags = sr->msg_flags;
6186 if (issue_flags & IO_URING_F_NONBLOCK)
6187 flags |= MSG_DONTWAIT;
6188 if (flags & MSG_WAITALL)
6189 min_ret = iov_iter_count(&msg.msg_iter);
6191 msg.msg_flags = flags;
6192 ret = sock_sendmsg(sock, &msg);
6193 if (ret < min_ret) {
6194 if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
6196 if (ret == -ERESTARTSYS)
6198 if (ret > 0 && io_net_retry(sock, flags)) {
6202 req->flags |= REQ_F_PARTIAL_IO;
6209 else if (sr->done_io)
6211 __io_req_complete(req, issue_flags, ret, 0);
6215 static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
6216 struct io_async_msghdr *iomsg)
6218 struct io_sr_msg *sr = &req->sr_msg;
6219 struct iovec __user *uiov;
6223 ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
6224 &iomsg->uaddr, &uiov, &iov_len);
6228 if (req->flags & REQ_F_BUFFER_SELECT) {
6231 if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
6233 sr->len = iomsg->fast_iov[0].iov_len;
6234 iomsg->free_iov = NULL;
6236 iomsg->free_iov = iomsg->fast_iov;
6237 ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
6238 &iomsg->free_iov, &iomsg->msg.msg_iter,
6247 #ifdef CONFIG_COMPAT
6248 static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
6249 struct io_async_msghdr *iomsg)
6251 struct io_sr_msg *sr = &req->sr_msg;
6252 struct compat_iovec __user *uiov;
6257 ret = __get_compat_msghdr(&iomsg->msg, sr->umsg_compat, &iomsg->uaddr,
6262 uiov = compat_ptr(ptr);
6263 if (req->flags & REQ_F_BUFFER_SELECT) {
6264 compat_ssize_t clen;
6268 if (!access_ok(uiov, sizeof(*uiov)))
6270 if (__get_user(clen, &uiov->iov_len))
6275 iomsg->free_iov = NULL;
6277 iomsg->free_iov = iomsg->fast_iov;
6278 ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
6279 UIO_FASTIOV, &iomsg->free_iov,
6280 &iomsg->msg.msg_iter, true);
6289 static int io_recvmsg_copy_hdr(struct io_kiocb *req,
6290 struct io_async_msghdr *iomsg)
6292 iomsg->msg.msg_name = &iomsg->addr;
6294 #ifdef CONFIG_COMPAT
6295 if (req->ctx->compat)
6296 return __io_compat_recvmsg_copy_hdr(req, iomsg);
6299 return __io_recvmsg_copy_hdr(req, iomsg);
6302 static int io_recvmsg_prep_async(struct io_kiocb *req)
6306 ret = io_recvmsg_copy_hdr(req, req->async_data);
6308 req->flags |= REQ_F_NEED_CLEANUP;
6312 static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
6314 struct io_sr_msg *sr = &req->sr_msg;
6316 if (unlikely(sqe->file_index))
6318 if (unlikely(sqe->addr2 || sqe->file_index))
6321 sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
6322 sr->len = READ_ONCE(sqe->len);
6323 sr->flags = READ_ONCE(sqe->addr2);
6324 if (sr->flags & ~IORING_RECVSEND_POLL_FIRST)
6326 sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
6327 if (sr->msg_flags & MSG_DONTWAIT)
6328 req->flags |= REQ_F_NOWAIT;
6330 #ifdef CONFIG_COMPAT
6331 if (req->ctx->compat)
6332 sr->msg_flags |= MSG_CMSG_COMPAT;
6338 static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
6340 struct io_async_msghdr iomsg, *kmsg;
6341 struct io_sr_msg *sr = &req->sr_msg;
6342 struct socket *sock;
6343 unsigned int cflags;
6345 int ret, min_ret = 0;
6346 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
6348 sock = sock_from_file(req->file);
6349 if (unlikely(!sock))
6352 if (req_has_async_data(req)) {
6353 kmsg = req->async_data;
6355 ret = io_recvmsg_copy_hdr(req, &iomsg);
6361 if (!(req->flags & REQ_F_POLLED) &&
6362 (sr->flags & IORING_RECVSEND_POLL_FIRST))
6363 return io_setup_async_msg(req, kmsg);
6365 if (io_do_buffer_select(req)) {
6368 buf = io_buffer_select(req, &sr->len, issue_flags);
6371 kmsg->fast_iov[0].iov_base = buf;
6372 kmsg->fast_iov[0].iov_len = sr->len;
6373 iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov, 1,
6377 flags = sr->msg_flags;
6379 flags |= MSG_DONTWAIT;
6380 if (flags & MSG_WAITALL)
6381 min_ret = iov_iter_count(&kmsg->msg.msg_iter);
6383 kmsg->msg.msg_get_inq = 1;
6384 ret = __sys_recvmsg_sock(sock, &kmsg->msg, sr->umsg, kmsg->uaddr, flags);
6385 if (ret < min_ret) {
6386 if (ret == -EAGAIN && force_nonblock)
6387 return io_setup_async_msg(req, kmsg);
6388 if (ret == -ERESTARTSYS)
6390 if (ret > 0 && io_net_retry(sock, flags)) {
6392 req->flags |= REQ_F_PARTIAL_IO;
6393 return io_setup_async_msg(req, kmsg);
6396 } else if ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
6400 /* fast path, check for non-NULL to avoid function call */
6402 kfree(kmsg->free_iov);
6403 req->flags &= ~REQ_F_NEED_CLEANUP;
6406 else if (sr->done_io)
6408 cflags = io_put_kbuf(req, issue_flags);
6409 if (kmsg->msg.msg_inq)
6410 cflags |= IORING_CQE_F_SOCK_NONEMPTY;
6411 __io_req_complete(req, issue_flags, ret, cflags);
6415 static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
6417 struct io_sr_msg *sr = &req->sr_msg;
6419 struct socket *sock;
6421 unsigned int cflags;
6423 int ret, min_ret = 0;
6424 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
6426 if (!(req->flags & REQ_F_POLLED) &&
6427 (sr->flags & IORING_RECVSEND_POLL_FIRST))
6430 sock = sock_from_file(req->file);
6431 if (unlikely(!sock))
6434 if (io_do_buffer_select(req)) {
6437 buf = io_buffer_select(req, &sr->len, issue_flags);
6443 ret = import_single_range(READ, sr->buf, sr->len, &iov, &msg.msg_iter);
6447 msg.msg_name = NULL;
6448 msg.msg_namelen = 0;
6449 msg.msg_control = NULL;
6450 msg.msg_get_inq = 1;
6452 msg.msg_controllen = 0;
6453 msg.msg_iocb = NULL;
6455 flags = sr->msg_flags;
6457 flags |= MSG_DONTWAIT;
6458 if (flags & MSG_WAITALL)
6459 min_ret = iov_iter_count(&msg.msg_iter);
6461 ret = sock_recvmsg(sock, &msg, flags);
6462 if (ret < min_ret) {
6463 if (ret == -EAGAIN && force_nonblock)
6465 if (ret == -ERESTARTSYS)
6467 if (ret > 0 && io_net_retry(sock, flags)) {
6471 req->flags |= REQ_F_PARTIAL_IO;
6475 } else if ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))) {
6482 else if (sr->done_io)
6484 cflags = io_put_kbuf(req, issue_flags);
6486 cflags |= IORING_CQE_F_SOCK_NONEMPTY;
6487 __io_req_complete(req, issue_flags, ret, cflags);
6491 static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
6493 struct io_accept *accept = &req->accept;
6496 if (sqe->len || sqe->buf_index)
6499 accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
6500 accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
6501 accept->flags = READ_ONCE(sqe->accept_flags);
6502 accept->nofile = rlimit(RLIMIT_NOFILE);
6503 flags = READ_ONCE(sqe->ioprio);
6504 if (flags & ~IORING_ACCEPT_MULTISHOT)
6507 accept->file_slot = READ_ONCE(sqe->file_index);
6508 if (accept->file_slot) {
6509 if (accept->flags & SOCK_CLOEXEC)
6511 if (flags & IORING_ACCEPT_MULTISHOT &&
6512 accept->file_slot != IORING_FILE_INDEX_ALLOC)
6515 if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
6517 if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
6518 accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
6519 if (flags & IORING_ACCEPT_MULTISHOT)
6520 req->flags |= REQ_F_APOLL_MULTISHOT;
6524 static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
6526 struct io_ring_ctx *ctx = req->ctx;
6527 struct io_accept *accept = &req->accept;
6528 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
6529 unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
6530 bool fixed = !!accept->file_slot;
6536 fd = __get_unused_fd_flags(accept->flags, accept->nofile);
6537 if (unlikely(fd < 0))
6540 file = do_accept(req->file, file_flags, accept->addr, accept->addr_len,
6545 ret = PTR_ERR(file);
6546 if (ret == -EAGAIN && force_nonblock) {
6548 * if it's multishot and polled, we don't need to
6549 * return EAGAIN to arm the poll infra since it
6550 * has already been done
6552 if ((req->flags & IO_APOLL_MULTI_POLLED) ==
6553 IO_APOLL_MULTI_POLLED)
6557 if (ret == -ERESTARTSYS)
6560 } else if (!fixed) {
6561 fd_install(fd, file);
6564 ret = io_fixed_fd_install(req, issue_flags, file,
6568 if (!(req->flags & REQ_F_APOLL_MULTISHOT)) {
6569 __io_req_complete(req, issue_flags, ret, 0);
6575 spin_lock(&ctx->completion_lock);
6576 filled = io_fill_cqe_aux(ctx, req->cqe.user_data, ret,
6578 io_commit_cqring(ctx);
6579 spin_unlock(&ctx->completion_lock);
6581 io_cqring_ev_posted(ctx);
6590 static int io_socket_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
6592 struct io_socket *sock = &req->sock;
6594 if (sqe->addr || sqe->rw_flags || sqe->buf_index)
6597 sock->domain = READ_ONCE(sqe->fd);
6598 sock->type = READ_ONCE(sqe->off);
6599 sock->protocol = READ_ONCE(sqe->len);
6600 sock->file_slot = READ_ONCE(sqe->file_index);
6601 sock->nofile = rlimit(RLIMIT_NOFILE);
6603 sock->flags = sock->type & ~SOCK_TYPE_MASK;
6604 if (sock->file_slot && (sock->flags & SOCK_CLOEXEC))
6606 if (sock->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
6611 static int io_socket(struct io_kiocb *req, unsigned int issue_flags)
6613 struct io_socket *sock = &req->sock;
6614 bool fixed = !!sock->file_slot;
6619 fd = __get_unused_fd_flags(sock->flags, sock->nofile);
6620 if (unlikely(fd < 0))
6623 file = __sys_socket_file(sock->domain, sock->type, sock->protocol);
6627 ret = PTR_ERR(file);
6628 if (ret == -EAGAIN && (issue_flags & IO_URING_F_NONBLOCK))
6630 if (ret == -ERESTARTSYS)
6633 } else if (!fixed) {
6634 fd_install(fd, file);
6637 ret = io_fixed_fd_install(req, issue_flags, file,
6640 __io_req_complete(req, issue_flags, ret, 0);
6644 static int io_connect_prep_async(struct io_kiocb *req)
6646 struct io_async_connect *io = req->async_data;
6647 struct io_connect *conn = &req->connect;
6649 return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
6652 static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
6654 struct io_connect *conn = &req->connect;
6656 if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
6659 conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
6660 conn->addr_len = READ_ONCE(sqe->addr2);
6664 static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
6666 struct io_async_connect __io, *io;
6667 unsigned file_flags;
6669 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
6671 if (req_has_async_data(req)) {
6672 io = req->async_data;
6674 ret = move_addr_to_kernel(req->connect.addr,
6675 req->connect.addr_len,
6682 file_flags = force_nonblock ? O_NONBLOCK : 0;
6684 ret = __sys_connect_file(req->file, &io->address,
6685 req->connect.addr_len, file_flags);
6686 if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
6687 if (req_has_async_data(req))
6689 if (io_alloc_async_data(req)) {
6693 memcpy(req->async_data, &__io, sizeof(__io));
6696 if (ret == -ERESTARTSYS)
6701 __io_req_complete(req, issue_flags, ret, 0);
6704 #else /* !CONFIG_NET */
6705 #define IO_NETOP_FN(op) \
6706 static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
6708 return -EOPNOTSUPP; \
6711 #define IO_NETOP_PREP(op) \
6713 static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
6715 return -EOPNOTSUPP; \
6718 #define IO_NETOP_PREP_ASYNC(op) \
6720 static int io_##op##_prep_async(struct io_kiocb *req) \
6722 return -EOPNOTSUPP; \
6725 IO_NETOP_PREP_ASYNC(sendmsg);
6726 IO_NETOP_PREP_ASYNC(recvmsg);
6727 IO_NETOP_PREP_ASYNC(connect);
6728 IO_NETOP_PREP(accept);
6729 IO_NETOP_PREP(socket);
6730 IO_NETOP_PREP(shutdown);
6733 #endif /* CONFIG_NET */
6735 struct io_poll_table {
6736 struct poll_table_struct pt;
6737 struct io_kiocb *req;
6742 #define IO_POLL_CANCEL_FLAG BIT(31)
6743 #define IO_POLL_REF_MASK GENMASK(30, 0)
6746 * If refs part of ->poll_refs (see IO_POLL_REF_MASK) is 0, it's free. We can
6747 * bump it and acquire ownership. It's disallowed to modify requests while not
6748 * owning it, that prevents from races for enqueueing task_work's and b/w
6749 * arming poll and wakeups.
6751 static inline bool io_poll_get_ownership(struct io_kiocb *req)
6753 return !(atomic_fetch_inc(&req->poll_refs) & IO_POLL_REF_MASK);
6756 static void io_poll_mark_cancelled(struct io_kiocb *req)
6758 atomic_or(IO_POLL_CANCEL_FLAG, &req->poll_refs);
6761 static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
6763 /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
6764 if (req->opcode == IORING_OP_POLL_ADD)
6765 return req->async_data;
6766 return req->apoll->double_poll;
6769 static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
6771 if (req->opcode == IORING_OP_POLL_ADD)
6773 return &req->apoll->poll;
6776 static void io_poll_req_insert(struct io_kiocb *req)
6778 struct io_ring_ctx *ctx = req->ctx;
6779 struct hlist_head *list;
6781 list = &ctx->cancel_hash[hash_long(req->cqe.user_data, ctx->cancel_hash_bits)];
6782 hlist_add_head(&req->hash_node, list);
6785 static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
6786 wait_queue_func_t wake_func)
6789 #define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
6790 /* mask in events that we always want/need */
6791 poll->events = events | IO_POLL_UNMASK;
6792 INIT_LIST_HEAD(&poll->wait.entry);
6793 init_waitqueue_func_entry(&poll->wait, wake_func);
6796 static inline void io_poll_remove_entry(struct io_poll_iocb *poll)
6798 struct wait_queue_head *head = smp_load_acquire(&poll->head);
6801 spin_lock_irq(&head->lock);
6802 list_del_init(&poll->wait.entry);
6804 spin_unlock_irq(&head->lock);
6808 static void io_poll_remove_entries(struct io_kiocb *req)
6811 * Nothing to do if neither of those flags are set. Avoid dipping
6812 * into the poll/apoll/double cachelines if we can.
6814 if (!(req->flags & (REQ_F_SINGLE_POLL | REQ_F_DOUBLE_POLL)))
6818 * While we hold the waitqueue lock and the waitqueue is nonempty,
6819 * wake_up_pollfree() will wait for us. However, taking the waitqueue
6820 * lock in the first place can race with the waitqueue being freed.
6822 * We solve this as eventpoll does: by taking advantage of the fact that
6823 * all users of wake_up_pollfree() will RCU-delay the actual free. If
6824 * we enter rcu_read_lock() and see that the pointer to the queue is
6825 * non-NULL, we can then lock it without the memory being freed out from
6828 * Keep holding rcu_read_lock() as long as we hold the queue lock, in
6829 * case the caller deletes the entry from the queue, leaving it empty.
6830 * In that case, only RCU prevents the queue memory from being freed.
6833 if (req->flags & REQ_F_SINGLE_POLL)
6834 io_poll_remove_entry(io_poll_get_single(req));
6835 if (req->flags & REQ_F_DOUBLE_POLL)
6836 io_poll_remove_entry(io_poll_get_double(req));
6840 static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags);
6842 * All poll tw should go through this. Checks for poll events, manages
6843 * references, does rewait, etc.
6845 * Returns a negative error on failure. >0 when no action require, which is
6846 * either spurious wakeup or multishot CQE is served. 0 when it's done with
6847 * the request, then the mask is stored in req->cqe.res.
6849 static int io_poll_check_events(struct io_kiocb *req, bool *locked)
6851 struct io_ring_ctx *ctx = req->ctx;
6854 /* req->task == current here, checking PF_EXITING is safe */
6855 if (unlikely(req->task->flags & PF_EXITING))
6859 v = atomic_read(&req->poll_refs);
6861 /* tw handler should be the owner, and so have some references */
6862 if (WARN_ON_ONCE(!(v & IO_POLL_REF_MASK)))
6864 if (v & IO_POLL_CANCEL_FLAG)
6867 if (!req->cqe.res) {
6868 struct poll_table_struct pt = { ._key = req->apoll_events };
6869 req->cqe.res = vfs_poll(req->file, &pt) & req->apoll_events;
6872 if ((unlikely(!req->cqe.res)))
6874 if (req->apoll_events & EPOLLONESHOT)
6877 /* multishot, just fill a CQE and proceed */
6878 if (!(req->flags & REQ_F_APOLL_MULTISHOT)) {
6879 __poll_t mask = mangle_poll(req->cqe.res &
6883 spin_lock(&ctx->completion_lock);
6884 filled = io_fill_cqe_aux(ctx, req->cqe.user_data,
6885 mask, IORING_CQE_F_MORE);
6886 io_commit_cqring(ctx);
6887 spin_unlock(&ctx->completion_lock);
6889 io_cqring_ev_posted(ctx);
6895 io_tw_lock(req->ctx, locked);
6896 if (unlikely(req->task->flags & PF_EXITING))
6898 ret = io_issue_sqe(req,
6899 IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
6904 * Release all references, retry if someone tried to restart
6905 * task_work while we were executing it.
6907 } while (atomic_sub_return(v & IO_POLL_REF_MASK, &req->poll_refs));
6912 static void io_poll_task_func(struct io_kiocb *req, bool *locked)
6914 struct io_ring_ctx *ctx = req->ctx;
6917 ret = io_poll_check_events(req, locked);
6922 req->cqe.res = mangle_poll(req->cqe.res & req->poll.events);
6928 io_poll_remove_entries(req);
6929 spin_lock(&ctx->completion_lock);
6930 hash_del(&req->hash_node);
6931 __io_req_complete_post(req, req->cqe.res, 0);
6932 io_commit_cqring(ctx);
6933 spin_unlock(&ctx->completion_lock);
6934 io_cqring_ev_posted(ctx);
6937 static void io_apoll_task_func(struct io_kiocb *req, bool *locked)
6939 struct io_ring_ctx *ctx = req->ctx;
6942 ret = io_poll_check_events(req, locked);
6946 io_poll_remove_entries(req);
6947 spin_lock(&ctx->completion_lock);
6948 hash_del(&req->hash_node);
6949 spin_unlock(&ctx->completion_lock);
6952 io_req_task_submit(req, locked);
6954 io_req_complete_failed(req, ret);
6957 static void __io_poll_execute(struct io_kiocb *req, int mask, __poll_t events)
6959 req->cqe.res = mask;
6961 * This is useful for poll that is armed on behalf of another
6962 * request, and where the wakeup path could be on a different
6963 * CPU. We want to avoid pulling in req->apoll->events for that
6966 req->apoll_events = events;
6967 if (req->opcode == IORING_OP_POLL_ADD)
6968 req->io_task_work.func = io_poll_task_func;
6970 req->io_task_work.func = io_apoll_task_func;
6972 trace_io_uring_task_add(req->ctx, req, req->cqe.user_data, req->opcode, mask);
6973 io_req_task_work_add(req);
6976 static inline void io_poll_execute(struct io_kiocb *req, int res,
6979 if (io_poll_get_ownership(req))
6980 __io_poll_execute(req, res, events);
6983 static void io_poll_cancel_req(struct io_kiocb *req)
6985 io_poll_mark_cancelled(req);
6986 /* kick tw, which should complete the request */
6987 io_poll_execute(req, 0, 0);
6990 #define wqe_to_req(wait) ((void *)((unsigned long) (wait)->private & ~1))
6991 #define wqe_is_double(wait) ((unsigned long) (wait)->private & 1)
6992 #define IO_ASYNC_POLL_COMMON (EPOLLONESHOT | EPOLLPRI)
6994 static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
6997 struct io_kiocb *req = wqe_to_req(wait);
6998 struct io_poll_iocb *poll = container_of(wait, struct io_poll_iocb,
7000 __poll_t mask = key_to_poll(key);
7002 if (unlikely(mask & POLLFREE)) {
7003 io_poll_mark_cancelled(req);
7004 /* we have to kick tw in case it's not already */
7005 io_poll_execute(req, 0, poll->events);
7008 * If the waitqueue is being freed early but someone is already
7009 * holds ownership over it, we have to tear down the request as
7010 * best we can. That means immediately removing the request from
7011 * its waitqueue and preventing all further accesses to the
7012 * waitqueue via the request.
7014 list_del_init(&poll->wait.entry);
7017 * Careful: this *must* be the last step, since as soon
7018 * as req->head is NULL'ed out, the request can be
7019 * completed and freed, since aio_poll_complete_work()
7020 * will no longer need to take the waitqueue lock.
7022 smp_store_release(&poll->head, NULL);
7026 /* for instances that support it check for an event match first */
7027 if (mask && !(mask & (poll->events & ~IO_ASYNC_POLL_COMMON)))
7030 if (io_poll_get_ownership(req)) {
7031 /* optional, saves extra locking for removal in tw handler */
7032 if (mask && poll->events & EPOLLONESHOT) {
7033 list_del_init(&poll->wait.entry);
7035 if (wqe_is_double(wait))
7036 req->flags &= ~REQ_F_DOUBLE_POLL;
7038 req->flags &= ~REQ_F_SINGLE_POLL;
7040 __io_poll_execute(req, mask, poll->events);
7045 static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
7046 struct wait_queue_head *head,
7047 struct io_poll_iocb **poll_ptr)
7049 struct io_kiocb *req = pt->req;
7050 unsigned long wqe_private = (unsigned long) req;
7053 * The file being polled uses multiple waitqueues for poll handling
7054 * (e.g. one for read, one for write). Setup a separate io_poll_iocb
7057 if (unlikely(pt->nr_entries)) {
7058 struct io_poll_iocb *first = poll;
7060 /* double add on the same waitqueue head, ignore */
7061 if (first->head == head)
7063 /* already have a 2nd entry, fail a third attempt */
7065 if ((*poll_ptr)->head == head)
7067 pt->error = -EINVAL;
7071 poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
7073 pt->error = -ENOMEM;
7076 /* mark as double wq entry */
7078 req->flags |= REQ_F_DOUBLE_POLL;
7079 io_init_poll_iocb(poll, first->events, first->wait.func);
7081 if (req->opcode == IORING_OP_POLL_ADD)
7082 req->flags |= REQ_F_ASYNC_DATA;
7085 req->flags |= REQ_F_SINGLE_POLL;
7088 poll->wait.private = (void *) wqe_private;
7090 if (poll->events & EPOLLEXCLUSIVE)
7091 add_wait_queue_exclusive(head, &poll->wait);
7093 add_wait_queue(head, &poll->wait);
7096 static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
7097 struct poll_table_struct *p)
7099 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
7101 __io_queue_proc(&pt->req->poll, pt, head,
7102 (struct io_poll_iocb **) &pt->req->async_data);
7105 static int __io_arm_poll_handler(struct io_kiocb *req,
7106 struct io_poll_iocb *poll,
7107 struct io_poll_table *ipt, __poll_t mask)
7109 struct io_ring_ctx *ctx = req->ctx;
7112 INIT_HLIST_NODE(&req->hash_node);
7113 req->work.cancel_seq = atomic_read(&ctx->cancel_seq);
7114 io_init_poll_iocb(poll, mask, io_poll_wake);
7115 poll->file = req->file;
7117 ipt->pt._key = mask;
7120 ipt->nr_entries = 0;
7123 * Take the ownership to delay any tw execution up until we're done
7124 * with poll arming. see io_poll_get_ownership().
7126 atomic_set(&req->poll_refs, 1);
7127 mask = vfs_poll(req->file, &ipt->pt) & poll->events;
7129 if (mask && (poll->events & EPOLLONESHOT)) {
7130 io_poll_remove_entries(req);
7131 /* no one else has access to the req, forget about the ref */
7134 if (!mask && unlikely(ipt->error || !ipt->nr_entries)) {
7135 io_poll_remove_entries(req);
7137 ipt->error = -EINVAL;
7141 spin_lock(&ctx->completion_lock);
7142 io_poll_req_insert(req);
7143 spin_unlock(&ctx->completion_lock);
7146 /* can't multishot if failed, just queue the event we've got */
7147 if (unlikely(ipt->error || !ipt->nr_entries))
7148 poll->events |= EPOLLONESHOT;
7149 __io_poll_execute(req, mask, poll->events);
7154 * Release ownership. If someone tried to queue a tw while it was
7155 * locked, kick it off for them.
7157 v = atomic_dec_return(&req->poll_refs);
7158 if (unlikely(v & IO_POLL_REF_MASK))
7159 __io_poll_execute(req, 0, poll->events);
7163 static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
7164 struct poll_table_struct *p)
7166 struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
7167 struct async_poll *apoll = pt->req->apoll;
7169 __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
7178 static int io_arm_poll_handler(struct io_kiocb *req, unsigned issue_flags)
7180 const struct io_op_def *def = &io_op_defs[req->opcode];
7181 struct io_ring_ctx *ctx = req->ctx;
7182 struct async_poll *apoll;
7183 struct io_poll_table ipt;
7184 __poll_t mask = POLLPRI | POLLERR;
7187 if (!def->pollin && !def->pollout)
7188 return IO_APOLL_ABORTED;
7189 if (!file_can_poll(req->file))
7190 return IO_APOLL_ABORTED;
7191 if ((req->flags & (REQ_F_POLLED|REQ_F_PARTIAL_IO)) == REQ_F_POLLED)
7192 return IO_APOLL_ABORTED;
7193 if (!(req->flags & REQ_F_APOLL_MULTISHOT))
7194 mask |= EPOLLONESHOT;
7197 mask |= EPOLLIN | EPOLLRDNORM;
7199 /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
7200 if ((req->opcode == IORING_OP_RECVMSG) &&
7201 (req->sr_msg.msg_flags & MSG_ERRQUEUE))
7204 mask |= EPOLLOUT | EPOLLWRNORM;
7206 if (def->poll_exclusive)
7207 mask |= EPOLLEXCLUSIVE;
7208 if (req->flags & REQ_F_POLLED) {
7210 } else if (!(issue_flags & IO_URING_F_UNLOCKED) &&
7211 !list_empty(&ctx->apoll_cache)) {
7212 apoll = list_first_entry(&ctx->apoll_cache, struct async_poll,
7214 list_del_init(&apoll->poll.wait.entry);
7216 apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
7217 if (unlikely(!apoll))
7218 return IO_APOLL_ABORTED;
7220 apoll->double_poll = NULL;
7222 req->flags |= REQ_F_POLLED;
7223 ipt.pt._qproc = io_async_queue_proc;
7225 io_kbuf_recycle(req, issue_flags);
7227 ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask);
7228 if (ret || ipt.error)
7229 return ret ? IO_APOLL_READY : IO_APOLL_ABORTED;
7231 trace_io_uring_poll_arm(ctx, req, req->cqe.user_data, req->opcode,
7232 mask, apoll->poll.events);
7237 * Returns true if we found and killed one or more poll requests
7239 static __cold bool io_poll_remove_all(struct io_ring_ctx *ctx,
7240 struct task_struct *tsk, bool cancel_all)
7242 struct hlist_node *tmp;
7243 struct io_kiocb *req;
7247 spin_lock(&ctx->completion_lock);
7248 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
7249 struct hlist_head *list;
7251 list = &ctx->cancel_hash[i];
7252 hlist_for_each_entry_safe(req, tmp, list, hash_node) {
7253 if (io_match_task_safe(req, tsk, cancel_all)) {
7254 hlist_del_init(&req->hash_node);
7255 io_poll_cancel_req(req);
7260 spin_unlock(&ctx->completion_lock);
7264 static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, bool poll_only,
7265 struct io_cancel_data *cd)
7266 __must_hold(&ctx->completion_lock)
7268 struct hlist_head *list;
7269 struct io_kiocb *req;
7271 list = &ctx->cancel_hash[hash_long(cd->data, ctx->cancel_hash_bits)];
7272 hlist_for_each_entry(req, list, hash_node) {
7273 if (cd->data != req->cqe.user_data)
7275 if (poll_only && req->opcode != IORING_OP_POLL_ADD)
7277 if (cd->flags & IORING_ASYNC_CANCEL_ALL) {
7278 if (cd->seq == req->work.cancel_seq)
7280 req->work.cancel_seq = cd->seq;
7287 static struct io_kiocb *io_poll_file_find(struct io_ring_ctx *ctx,
7288 struct io_cancel_data *cd)
7289 __must_hold(&ctx->completion_lock)
7291 struct io_kiocb *req;
7294 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
7295 struct hlist_head *list;
7297 list = &ctx->cancel_hash[i];
7298 hlist_for_each_entry(req, list, hash_node) {
7299 if (!(cd->flags & IORING_ASYNC_CANCEL_ANY) &&
7300 req->file != cd->file)
7302 if (cd->seq == req->work.cancel_seq)
7304 req->work.cancel_seq = cd->seq;
7311 static bool io_poll_disarm(struct io_kiocb *req)
7312 __must_hold(&ctx->completion_lock)
7314 if (!io_poll_get_ownership(req))
7316 io_poll_remove_entries(req);
7317 hash_del(&req->hash_node);
7321 static int io_poll_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
7322 __must_hold(&ctx->completion_lock)
7324 struct io_kiocb *req;
7326 if (cd->flags & (IORING_ASYNC_CANCEL_FD|IORING_ASYNC_CANCEL_ANY))
7327 req = io_poll_file_find(ctx, cd);
7329 req = io_poll_find(ctx, false, cd);
7332 io_poll_cancel_req(req);
7336 static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
7341 events = READ_ONCE(sqe->poll32_events);
7343 events = swahw32(events);
7345 if (!(flags & IORING_POLL_ADD_MULTI))
7346 events |= EPOLLONESHOT;
7347 return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
7350 static int io_poll_remove_prep(struct io_kiocb *req,
7351 const struct io_uring_sqe *sqe)
7353 struct io_poll_update *upd = &req->poll_update;
7356 if (sqe->buf_index || sqe->splice_fd_in)
7358 flags = READ_ONCE(sqe->len);
7359 if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA |
7360 IORING_POLL_ADD_MULTI))
7362 /* meaningless without update */
7363 if (flags == IORING_POLL_ADD_MULTI)
7366 upd->old_user_data = READ_ONCE(sqe->addr);
7367 upd->update_events = flags & IORING_POLL_UPDATE_EVENTS;
7368 upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA;
7370 upd->new_user_data = READ_ONCE(sqe->off);
7371 if (!upd->update_user_data && upd->new_user_data)
7373 if (upd->update_events)
7374 upd->events = io_poll_parse_events(sqe, flags);
7375 else if (sqe->poll32_events)
7381 static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
7383 struct io_poll_iocb *poll = &req->poll;
7386 if (sqe->buf_index || sqe->off || sqe->addr)
7388 flags = READ_ONCE(sqe->len);
7389 if (flags & ~IORING_POLL_ADD_MULTI)
7391 if ((flags & IORING_POLL_ADD_MULTI) && (req->flags & REQ_F_CQE_SKIP))
7394 io_req_set_refcount(req);
7395 req->apoll_events = poll->events = io_poll_parse_events(sqe, flags);
7399 static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
7401 struct io_poll_iocb *poll = &req->poll;
7402 struct io_poll_table ipt;
7405 ipt.pt._qproc = io_poll_queue_proc;
7407 ret = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events);
7408 ret = ret ?: ipt.error;
7410 __io_req_complete(req, issue_flags, ret, 0);
7414 static int io_poll_remove(struct io_kiocb *req, unsigned int issue_flags)
7416 struct io_cancel_data cd = { .data = req->poll_update.old_user_data, };
7417 struct io_ring_ctx *ctx = req->ctx;
7418 struct io_kiocb *preq;
7422 spin_lock(&ctx->completion_lock);
7423 preq = io_poll_find(ctx, true, &cd);
7424 if (!preq || !io_poll_disarm(preq)) {
7425 spin_unlock(&ctx->completion_lock);
7426 ret = preq ? -EALREADY : -ENOENT;
7429 spin_unlock(&ctx->completion_lock);
7431 if (req->poll_update.update_events || req->poll_update.update_user_data) {
7432 /* only mask one event flags, keep behavior flags */
7433 if (req->poll_update.update_events) {
7434 preq->poll.events &= ~0xffff;
7435 preq->poll.events |= req->poll_update.events & 0xffff;
7436 preq->poll.events |= IO_POLL_UNMASK;
7438 if (req->poll_update.update_user_data)
7439 preq->cqe.user_data = req->poll_update.new_user_data;
7441 ret2 = io_poll_add(preq, issue_flags);
7442 /* successfully updated, don't complete poll request */
7448 preq->cqe.res = -ECANCELED;
7449 locked = !(issue_flags & IO_URING_F_UNLOCKED);
7450 io_req_task_complete(preq, &locked);
7454 /* complete update request, we're done with it */
7455 __io_req_complete(req, issue_flags, ret, 0);
7459 static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
7461 struct io_timeout_data *data = container_of(timer,
7462 struct io_timeout_data, timer);
7463 struct io_kiocb *req = data->req;
7464 struct io_ring_ctx *ctx = req->ctx;
7465 unsigned long flags;
7467 spin_lock_irqsave(&ctx->timeout_lock, flags);
7468 list_del_init(&req->timeout.list);
7469 atomic_set(&req->ctx->cq_timeouts,
7470 atomic_read(&req->ctx->cq_timeouts) + 1);
7471 spin_unlock_irqrestore(&ctx->timeout_lock, flags);
7473 if (!(data->flags & IORING_TIMEOUT_ETIME_SUCCESS))
7476 req->cqe.res = -ETIME;
7477 req->io_task_work.func = io_req_task_complete;
7478 io_req_task_work_add(req);
7479 return HRTIMER_NORESTART;
7482 static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
7483 struct io_cancel_data *cd)
7484 __must_hold(&ctx->timeout_lock)
7486 struct io_timeout_data *io;
7487 struct io_kiocb *req;
7490 list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
7491 if (!(cd->flags & IORING_ASYNC_CANCEL_ANY) &&
7492 cd->data != req->cqe.user_data)
7494 if (cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY)) {
7495 if (cd->seq == req->work.cancel_seq)
7497 req->work.cancel_seq = cd->seq;
7503 return ERR_PTR(-ENOENT);
7505 io = req->async_data;
7506 if (hrtimer_try_to_cancel(&io->timer) == -1)
7507 return ERR_PTR(-EALREADY);
7508 list_del_init(&req->timeout.list);
7512 static int io_timeout_cancel(struct io_ring_ctx *ctx, struct io_cancel_data *cd)
7513 __must_hold(&ctx->completion_lock)
7515 struct io_kiocb *req;
7517 spin_lock_irq(&ctx->timeout_lock);
7518 req = io_timeout_extract(ctx, cd);
7519 spin_unlock_irq(&ctx->timeout_lock);
7522 return PTR_ERR(req);
7523 io_req_task_queue_fail(req, -ECANCELED);
7527 static clockid_t io_timeout_get_clock(struct io_timeout_data *data)
7529 switch (data->flags & IORING_TIMEOUT_CLOCK_MASK) {
7530 case IORING_TIMEOUT_BOOTTIME:
7531 return CLOCK_BOOTTIME;
7532 case IORING_TIMEOUT_REALTIME:
7533 return CLOCK_REALTIME;
7535 /* can't happen, vetted at prep time */
7539 return CLOCK_MONOTONIC;
7543 static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
7544 struct timespec64 *ts, enum hrtimer_mode mode)
7545 __must_hold(&ctx->timeout_lock)
7547 struct io_timeout_data *io;
7548 struct io_kiocb *req;
7551 list_for_each_entry(req, &ctx->ltimeout_list, timeout.list) {
7552 found = user_data == req->cqe.user_data;
7559 io = req->async_data;
7560 if (hrtimer_try_to_cancel(&io->timer) == -1)
7562 hrtimer_init(&io->timer, io_timeout_get_clock(io), mode);
7563 io->timer.function = io_link_timeout_fn;
7564 hrtimer_start(&io->timer, timespec64_to_ktime(*ts), mode);
7568 static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
7569 struct timespec64 *ts, enum hrtimer_mode mode)
7570 __must_hold(&ctx->timeout_lock)
7572 struct io_cancel_data cd = { .data = user_data, };
7573 struct io_kiocb *req = io_timeout_extract(ctx, &cd);
7574 struct io_timeout_data *data;
7577 return PTR_ERR(req);
7579 req->timeout.off = 0; /* noseq */
7580 data = req->async_data;
7581 list_add_tail(&req->timeout.list, &ctx->timeout_list);
7582 hrtimer_init(&data->timer, io_timeout_get_clock(data), mode);
7583 data->timer.function = io_timeout_fn;
7584 hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
7588 static int io_timeout_remove_prep(struct io_kiocb *req,
7589 const struct io_uring_sqe *sqe)
7591 struct io_timeout_rem *tr = &req->timeout_rem;
7593 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
7595 if (sqe->buf_index || sqe->len || sqe->splice_fd_in)
7598 tr->ltimeout = false;
7599 tr->addr = READ_ONCE(sqe->addr);
7600 tr->flags = READ_ONCE(sqe->timeout_flags);
7601 if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) {
7602 if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
7604 if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
7605 tr->ltimeout = true;
7606 if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK|IORING_TIMEOUT_ABS))
7608 if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
7610 if (tr->ts.tv_sec < 0 || tr->ts.tv_nsec < 0)
7612 } else if (tr->flags) {
7613 /* timeout removal doesn't support flags */
7620 static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
7622 return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
7627 * Remove or update an existing timeout command
7629 static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
7631 struct io_timeout_rem *tr = &req->timeout_rem;
7632 struct io_ring_ctx *ctx = req->ctx;
7635 if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE)) {
7636 struct io_cancel_data cd = { .data = tr->addr, };
7638 spin_lock(&ctx->completion_lock);
7639 ret = io_timeout_cancel(ctx, &cd);
7640 spin_unlock(&ctx->completion_lock);
7642 enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags);
7644 spin_lock_irq(&ctx->timeout_lock);
7646 ret = io_linked_timeout_update(ctx, tr->addr, &tr->ts, mode);
7648 ret = io_timeout_update(ctx, tr->addr, &tr->ts, mode);
7649 spin_unlock_irq(&ctx->timeout_lock);
7654 io_req_complete_post(req, ret, 0);
7658 static int __io_timeout_prep(struct io_kiocb *req,
7659 const struct io_uring_sqe *sqe,
7660 bool is_timeout_link)
7662 struct io_timeout_data *data;
7664 u32 off = READ_ONCE(sqe->off);
7666 if (sqe->buf_index || sqe->len != 1 || sqe->splice_fd_in)
7668 if (off && is_timeout_link)
7670 flags = READ_ONCE(sqe->timeout_flags);
7671 if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK |
7672 IORING_TIMEOUT_ETIME_SUCCESS))
7674 /* more than one clock specified is invalid, obviously */
7675 if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
7678 INIT_LIST_HEAD(&req->timeout.list);
7679 req->timeout.off = off;
7680 if (unlikely(off && !req->ctx->off_timeout_used))
7681 req->ctx->off_timeout_used = true;
7683 if (WARN_ON_ONCE(req_has_async_data(req)))
7685 if (io_alloc_async_data(req))
7688 data = req->async_data;
7690 data->flags = flags;
7692 if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
7695 if (data->ts.tv_sec < 0 || data->ts.tv_nsec < 0)
7698 INIT_LIST_HEAD(&req->timeout.list);
7699 data->mode = io_translate_timeout_mode(flags);
7700 hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode);
7702 if (is_timeout_link) {
7703 struct io_submit_link *link = &req->ctx->submit_state.link;
7707 if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
7709 req->timeout.head = link->last;
7710 link->last->flags |= REQ_F_ARM_LTIMEOUT;
7715 static int io_timeout_prep(struct io_kiocb *req,
7716 const struct io_uring_sqe *sqe)
7718 return __io_timeout_prep(req, sqe, false);
7721 static int io_link_timeout_prep(struct io_kiocb *req,
7722 const struct io_uring_sqe *sqe)
7724 return __io_timeout_prep(req, sqe, true);
7727 static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
7729 struct io_ring_ctx *ctx = req->ctx;
7730 struct io_timeout_data *data = req->async_data;
7731 struct list_head *entry;
7732 u32 tail, off = req->timeout.off;
7734 spin_lock_irq(&ctx->timeout_lock);
7737 * sqe->off holds how many events that need to occur for this
7738 * timeout event to be satisfied. If it isn't set, then this is
7739 * a pure timeout request, sequence isn't used.
7741 if (io_is_timeout_noseq(req)) {
7742 entry = ctx->timeout_list.prev;
7746 tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
7747 req->timeout.target_seq = tail + off;
7749 /* Update the last seq here in case io_flush_timeouts() hasn't.
7750 * This is safe because ->completion_lock is held, and submissions
7751 * and completions are never mixed in the same ->completion_lock section.
7753 ctx->cq_last_tm_flush = tail;
7756 * Insertion sort, ensuring the first entry in the list is always
7757 * the one we need first.
7759 list_for_each_prev(entry, &ctx->timeout_list) {
7760 struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
7763 if (io_is_timeout_noseq(nxt))
7765 /* nxt.seq is behind @tail, otherwise would've been completed */
7766 if (off >= nxt->timeout.target_seq - tail)
7770 list_add(&req->timeout.list, entry);
7771 data->timer.function = io_timeout_fn;
7772 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
7773 spin_unlock_irq(&ctx->timeout_lock);
7777 static bool io_cancel_cb(struct io_wq_work *work, void *data)
7779 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
7780 struct io_cancel_data *cd = data;
7782 if (req->ctx != cd->ctx)
7784 if (cd->flags & IORING_ASYNC_CANCEL_ANY) {
7786 } else if (cd->flags & IORING_ASYNC_CANCEL_FD) {
7787 if (req->file != cd->file)
7790 if (req->cqe.user_data != cd->data)
7793 if (cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY)) {
7794 if (cd->seq == req->work.cancel_seq)
7796 req->work.cancel_seq = cd->seq;
7801 static int io_async_cancel_one(struct io_uring_task *tctx,
7802 struct io_cancel_data *cd)
7804 enum io_wq_cancel cancel_ret;
7808 if (!tctx || !tctx->io_wq)
7811 all = cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY);
7812 cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, cd, all);
7813 switch (cancel_ret) {
7814 case IO_WQ_CANCEL_OK:
7817 case IO_WQ_CANCEL_RUNNING:
7820 case IO_WQ_CANCEL_NOTFOUND:
7828 static int io_try_cancel(struct io_kiocb *req, struct io_cancel_data *cd)
7830 struct io_ring_ctx *ctx = req->ctx;
7833 WARN_ON_ONCE(!io_wq_current_is_worker() && req->task != current);
7835 ret = io_async_cancel_one(req->task->io_uring, cd);
7837 * Fall-through even for -EALREADY, as we may have poll armed
7838 * that need unarming.
7843 spin_lock(&ctx->completion_lock);
7844 ret = io_poll_cancel(ctx, cd);
7847 if (!(cd->flags & IORING_ASYNC_CANCEL_FD))
7848 ret = io_timeout_cancel(ctx, cd);
7850 spin_unlock(&ctx->completion_lock);
7854 #define CANCEL_FLAGS (IORING_ASYNC_CANCEL_ALL | IORING_ASYNC_CANCEL_FD | \
7855 IORING_ASYNC_CANCEL_ANY)
7857 static int io_async_cancel_prep(struct io_kiocb *req,
7858 const struct io_uring_sqe *sqe)
7860 if (unlikely(req->flags & REQ_F_BUFFER_SELECT))
7862 if (sqe->off || sqe->len || sqe->splice_fd_in)
7865 req->cancel.addr = READ_ONCE(sqe->addr);
7866 req->cancel.flags = READ_ONCE(sqe->cancel_flags);
7867 if (req->cancel.flags & ~CANCEL_FLAGS)
7869 if (req->cancel.flags & IORING_ASYNC_CANCEL_FD) {
7870 if (req->cancel.flags & IORING_ASYNC_CANCEL_ANY)
7872 req->cancel.fd = READ_ONCE(sqe->fd);
7878 static int __io_async_cancel(struct io_cancel_data *cd, struct io_kiocb *req,
7879 unsigned int issue_flags)
7881 bool all = cd->flags & (IORING_ASYNC_CANCEL_ALL|IORING_ASYNC_CANCEL_ANY);
7882 struct io_ring_ctx *ctx = cd->ctx;
7883 struct io_tctx_node *node;
7887 ret = io_try_cancel(req, cd);
7895 /* slow path, try all io-wq's */
7896 io_ring_submit_lock(ctx, issue_flags);
7898 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
7899 struct io_uring_task *tctx = node->task->io_uring;
7901 ret = io_async_cancel_one(tctx, cd);
7902 if (ret != -ENOENT) {
7908 io_ring_submit_unlock(ctx, issue_flags);
7909 return all ? nr : ret;
7912 static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
7914 struct io_cancel_data cd = {
7916 .data = req->cancel.addr,
7917 .flags = req->cancel.flags,
7918 .seq = atomic_inc_return(&req->ctx->cancel_seq),
7922 if (cd.flags & IORING_ASYNC_CANCEL_FD) {
7923 if (req->flags & REQ_F_FIXED_FILE)
7924 req->file = io_file_get_fixed(req, req->cancel.fd,
7927 req->file = io_file_get_normal(req, req->cancel.fd);
7932 cd.file = req->file;
7935 ret = __io_async_cancel(&cd, req, issue_flags);
7939 io_req_complete_post(req, ret, 0);
7943 static int io_files_update_prep(struct io_kiocb *req,
7944 const struct io_uring_sqe *sqe)
7946 if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
7948 if (sqe->rw_flags || sqe->splice_fd_in)
7951 req->rsrc_update.offset = READ_ONCE(sqe->off);
7952 req->rsrc_update.nr_args = READ_ONCE(sqe->len);
7953 if (!req->rsrc_update.nr_args)
7955 req->rsrc_update.arg = READ_ONCE(sqe->addr);
7959 static int io_files_update_with_index_alloc(struct io_kiocb *req,
7960 unsigned int issue_flags)
7962 __s32 __user *fds = u64_to_user_ptr(req->rsrc_update.arg);
7967 for (done = 0; done < req->rsrc_update.nr_args; done++) {
7968 if (copy_from_user(&fd, &fds[done], sizeof(fd))) {
7978 ret = io_fixed_fd_install(req, issue_flags, file,
7979 IORING_FILE_INDEX_ALLOC);
7982 if (copy_to_user(&fds[done], &ret, sizeof(ret))) {
7983 __io_close_fixed(req, issue_flags, ret);
7994 static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
7996 struct io_ring_ctx *ctx = req->ctx;
7997 struct io_uring_rsrc_update2 up;
8000 up.offset = req->rsrc_update.offset;
8001 up.data = req->rsrc_update.arg;
8007 if (req->rsrc_update.offset == IORING_FILE_INDEX_ALLOC) {
8008 ret = io_files_update_with_index_alloc(req, issue_flags);
8010 io_ring_submit_lock(ctx, issue_flags);
8011 ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
8012 &up, req->rsrc_update.nr_args);
8013 io_ring_submit_unlock(ctx, issue_flags);
8018 __io_req_complete(req, issue_flags, ret, 0);
8022 static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
8024 switch (req->opcode) {
8026 return io_nop_prep(req, sqe);
8027 case IORING_OP_READV:
8028 case IORING_OP_READ_FIXED:
8029 case IORING_OP_READ:
8030 case IORING_OP_WRITEV:
8031 case IORING_OP_WRITE_FIXED:
8032 case IORING_OP_WRITE:
8033 return io_prep_rw(req, sqe);
8034 case IORING_OP_POLL_ADD:
8035 return io_poll_add_prep(req, sqe);
8036 case IORING_OP_POLL_REMOVE:
8037 return io_poll_remove_prep(req, sqe);
8038 case IORING_OP_FSYNC:
8039 return io_fsync_prep(req, sqe);
8040 case IORING_OP_SYNC_FILE_RANGE:
8041 return io_sfr_prep(req, sqe);
8042 case IORING_OP_SENDMSG:
8043 case IORING_OP_SEND:
8044 return io_sendmsg_prep(req, sqe);
8045 case IORING_OP_RECVMSG:
8046 case IORING_OP_RECV:
8047 return io_recvmsg_prep(req, sqe);
8048 case IORING_OP_CONNECT:
8049 return io_connect_prep(req, sqe);
8050 case IORING_OP_TIMEOUT:
8051 return io_timeout_prep(req, sqe);
8052 case IORING_OP_TIMEOUT_REMOVE:
8053 return io_timeout_remove_prep(req, sqe);
8054 case IORING_OP_ASYNC_CANCEL:
8055 return io_async_cancel_prep(req, sqe);
8056 case IORING_OP_LINK_TIMEOUT:
8057 return io_link_timeout_prep(req, sqe);
8058 case IORING_OP_ACCEPT:
8059 return io_accept_prep(req, sqe);
8060 case IORING_OP_FALLOCATE:
8061 return io_fallocate_prep(req, sqe);
8062 case IORING_OP_OPENAT:
8063 return io_openat_prep(req, sqe);
8064 case IORING_OP_CLOSE:
8065 return io_close_prep(req, sqe);
8066 case IORING_OP_FILES_UPDATE:
8067 return io_files_update_prep(req, sqe);
8068 case IORING_OP_STATX:
8069 return io_statx_prep(req, sqe);
8070 case IORING_OP_FADVISE:
8071 return io_fadvise_prep(req, sqe);
8072 case IORING_OP_MADVISE:
8073 return io_madvise_prep(req, sqe);
8074 case IORING_OP_OPENAT2:
8075 return io_openat2_prep(req, sqe);
8076 case IORING_OP_EPOLL_CTL:
8077 return io_epoll_ctl_prep(req, sqe);
8078 case IORING_OP_SPLICE:
8079 return io_splice_prep(req, sqe);
8080 case IORING_OP_PROVIDE_BUFFERS:
8081 return io_provide_buffers_prep(req, sqe);
8082 case IORING_OP_REMOVE_BUFFERS:
8083 return io_remove_buffers_prep(req, sqe);
8085 return io_tee_prep(req, sqe);
8086 case IORING_OP_SHUTDOWN:
8087 return io_shutdown_prep(req, sqe);
8088 case IORING_OP_RENAMEAT:
8089 return io_renameat_prep(req, sqe);
8090 case IORING_OP_UNLINKAT:
8091 return io_unlinkat_prep(req, sqe);
8092 case IORING_OP_MKDIRAT:
8093 return io_mkdirat_prep(req, sqe);
8094 case IORING_OP_SYMLINKAT:
8095 return io_symlinkat_prep(req, sqe);
8096 case IORING_OP_LINKAT:
8097 return io_linkat_prep(req, sqe);
8098 case IORING_OP_MSG_RING:
8099 return io_msg_ring_prep(req, sqe);
8100 case IORING_OP_FSETXATTR:
8101 return io_fsetxattr_prep(req, sqe);
8102 case IORING_OP_SETXATTR:
8103 return io_setxattr_prep(req, sqe);
8104 case IORING_OP_FGETXATTR:
8105 return io_fgetxattr_prep(req, sqe);
8106 case IORING_OP_GETXATTR:
8107 return io_getxattr_prep(req, sqe);
8108 case IORING_OP_SOCKET:
8109 return io_socket_prep(req, sqe);
8110 case IORING_OP_URING_CMD:
8111 return io_uring_cmd_prep(req, sqe);
8114 printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
8119 static int io_req_prep_async(struct io_kiocb *req)
8121 const struct io_op_def *def = &io_op_defs[req->opcode];
8123 /* assign early for deferred execution for non-fixed file */
8124 if (def->needs_file && !(req->flags & REQ_F_FIXED_FILE))
8125 req->file = io_file_get_normal(req, req->cqe.fd);
8126 if (!def->needs_async_setup)
8128 if (WARN_ON_ONCE(req_has_async_data(req)))
8130 if (io_alloc_async_data(req))
8133 switch (req->opcode) {
8134 case IORING_OP_READV:
8135 return io_readv_prep_async(req);
8136 case IORING_OP_WRITEV:
8137 return io_writev_prep_async(req);
8138 case IORING_OP_SENDMSG:
8139 return io_sendmsg_prep_async(req);
8140 case IORING_OP_RECVMSG:
8141 return io_recvmsg_prep_async(req);
8142 case IORING_OP_CONNECT:
8143 return io_connect_prep_async(req);
8144 case IORING_OP_URING_CMD:
8145 return io_uring_cmd_prep_async(req);
8147 printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n",
8152 static u32 io_get_sequence(struct io_kiocb *req)
8154 u32 seq = req->ctx->cached_sq_head;
8155 struct io_kiocb *cur;
8157 /* need original cached_sq_head, but it was increased for each req */
8158 io_for_each_link(cur, req)
8163 static __cold void io_drain_req(struct io_kiocb *req)
8165 struct io_ring_ctx *ctx = req->ctx;
8166 struct io_defer_entry *de;
8168 u32 seq = io_get_sequence(req);
8170 /* Still need defer if there is pending req in defer list. */
8171 spin_lock(&ctx->completion_lock);
8172 if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list)) {
8173 spin_unlock(&ctx->completion_lock);
8175 ctx->drain_active = false;
8176 io_req_task_queue(req);
8179 spin_unlock(&ctx->completion_lock);
8181 ret = io_req_prep_async(req);
8184 io_req_complete_failed(req, ret);
8187 io_prep_async_link(req);
8188 de = kmalloc(sizeof(*de), GFP_KERNEL);
8194 spin_lock(&ctx->completion_lock);
8195 if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
8196 spin_unlock(&ctx->completion_lock);
8201 trace_io_uring_defer(ctx, req, req->cqe.user_data, req->opcode);
8204 list_add_tail(&de->list, &ctx->defer_list);
8205 spin_unlock(&ctx->completion_lock);
8208 static void io_clean_op(struct io_kiocb *req)
8210 if (req->flags & REQ_F_BUFFER_SELECTED) {
8211 spin_lock(&req->ctx->completion_lock);
8212 io_put_kbuf_comp(req);
8213 spin_unlock(&req->ctx->completion_lock);
8216 if (req->flags & REQ_F_NEED_CLEANUP) {
8217 switch (req->opcode) {
8218 case IORING_OP_READV:
8219 case IORING_OP_READ_FIXED:
8220 case IORING_OP_READ:
8221 case IORING_OP_WRITEV:
8222 case IORING_OP_WRITE_FIXED:
8223 case IORING_OP_WRITE: {
8224 struct io_async_rw *io = req->async_data;
8226 kfree(io->free_iovec);
8229 case IORING_OP_RECVMSG:
8230 case IORING_OP_SENDMSG: {
8231 struct io_async_msghdr *io = req->async_data;
8233 kfree(io->free_iov);
8236 case IORING_OP_OPENAT:
8237 case IORING_OP_OPENAT2:
8238 if (req->open.filename)
8239 putname(req->open.filename);
8241 case IORING_OP_RENAMEAT:
8242 putname(req->rename.oldpath);
8243 putname(req->rename.newpath);
8245 case IORING_OP_UNLINKAT:
8246 putname(req->unlink.filename);
8248 case IORING_OP_MKDIRAT:
8249 putname(req->mkdir.filename);
8251 case IORING_OP_SYMLINKAT:
8252 putname(req->symlink.oldpath);
8253 putname(req->symlink.newpath);
8255 case IORING_OP_LINKAT:
8256 putname(req->hardlink.oldpath);
8257 putname(req->hardlink.newpath);
8259 case IORING_OP_STATX:
8260 if (req->statx.filename)
8261 putname(req->statx.filename);
8263 case IORING_OP_SETXATTR:
8264 case IORING_OP_FSETXATTR:
8265 case IORING_OP_GETXATTR:
8266 case IORING_OP_FGETXATTR:
8267 __io_xattr_finish(req);
8271 if ((req->flags & REQ_F_POLLED) && req->apoll) {
8272 kfree(req->apoll->double_poll);
8276 if (req->flags & REQ_F_INFLIGHT) {
8277 struct io_uring_task *tctx = req->task->io_uring;
8279 atomic_dec(&tctx->inflight_tracked);
8281 if (req->flags & REQ_F_CREDS)
8282 put_cred(req->creds);
8283 if (req->flags & REQ_F_ASYNC_DATA) {
8284 kfree(req->async_data);
8285 req->async_data = NULL;
8287 req->flags &= ~IO_REQ_CLEAN_FLAGS;
8290 static bool io_assign_file(struct io_kiocb *req, unsigned int issue_flags)
8292 if (req->file || !io_op_defs[req->opcode].needs_file)
8295 if (req->flags & REQ_F_FIXED_FILE)
8296 req->file = io_file_get_fixed(req, req->cqe.fd, issue_flags);
8298 req->file = io_file_get_normal(req, req->cqe.fd);
8303 static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
8305 const struct io_op_def *def = &io_op_defs[req->opcode];
8306 const struct cred *creds = NULL;
8309 if (unlikely(!io_assign_file(req, issue_flags)))
8312 if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred()))
8313 creds = override_creds(req->creds);
8315 if (!def->audit_skip)
8316 audit_uring_entry(req->opcode);
8318 switch (req->opcode) {
8320 ret = io_nop(req, issue_flags);
8322 case IORING_OP_READV:
8323 case IORING_OP_READ_FIXED:
8324 case IORING_OP_READ:
8325 ret = io_read(req, issue_flags);
8327 case IORING_OP_WRITEV:
8328 case IORING_OP_WRITE_FIXED:
8329 case IORING_OP_WRITE:
8330 ret = io_write(req, issue_flags);
8332 case IORING_OP_FSYNC:
8333 ret = io_fsync(req, issue_flags);
8335 case IORING_OP_POLL_ADD:
8336 ret = io_poll_add(req, issue_flags);
8338 case IORING_OP_POLL_REMOVE:
8339 ret = io_poll_remove(req, issue_flags);
8341 case IORING_OP_SYNC_FILE_RANGE:
8342 ret = io_sync_file_range(req, issue_flags);
8344 case IORING_OP_SENDMSG:
8345 ret = io_sendmsg(req, issue_flags);
8347 case IORING_OP_SEND:
8348 ret = io_send(req, issue_flags);
8350 case IORING_OP_RECVMSG:
8351 ret = io_recvmsg(req, issue_flags);
8353 case IORING_OP_RECV:
8354 ret = io_recv(req, issue_flags);
8356 case IORING_OP_TIMEOUT:
8357 ret = io_timeout(req, issue_flags);
8359 case IORING_OP_TIMEOUT_REMOVE:
8360 ret = io_timeout_remove(req, issue_flags);
8362 case IORING_OP_ACCEPT:
8363 ret = io_accept(req, issue_flags);
8365 case IORING_OP_CONNECT:
8366 ret = io_connect(req, issue_flags);
8368 case IORING_OP_ASYNC_CANCEL:
8369 ret = io_async_cancel(req, issue_flags);
8371 case IORING_OP_FALLOCATE:
8372 ret = io_fallocate(req, issue_flags);
8374 case IORING_OP_OPENAT:
8375 ret = io_openat(req, issue_flags);
8377 case IORING_OP_CLOSE:
8378 ret = io_close(req, issue_flags);
8380 case IORING_OP_FILES_UPDATE:
8381 ret = io_files_update(req, issue_flags);
8383 case IORING_OP_STATX:
8384 ret = io_statx(req, issue_flags);
8386 case IORING_OP_FADVISE:
8387 ret = io_fadvise(req, issue_flags);
8389 case IORING_OP_MADVISE:
8390 ret = io_madvise(req, issue_flags);
8392 case IORING_OP_OPENAT2:
8393 ret = io_openat2(req, issue_flags);
8395 case IORING_OP_EPOLL_CTL:
8396 ret = io_epoll_ctl(req, issue_flags);
8398 case IORING_OP_SPLICE:
8399 ret = io_splice(req, issue_flags);
8401 case IORING_OP_PROVIDE_BUFFERS:
8402 ret = io_provide_buffers(req, issue_flags);
8404 case IORING_OP_REMOVE_BUFFERS:
8405 ret = io_remove_buffers(req, issue_flags);
8408 ret = io_tee(req, issue_flags);
8410 case IORING_OP_SHUTDOWN:
8411 ret = io_shutdown(req, issue_flags);
8413 case IORING_OP_RENAMEAT:
8414 ret = io_renameat(req, issue_flags);
8416 case IORING_OP_UNLINKAT:
8417 ret = io_unlinkat(req, issue_flags);
8419 case IORING_OP_MKDIRAT:
8420 ret = io_mkdirat(req, issue_flags);
8422 case IORING_OP_SYMLINKAT:
8423 ret = io_symlinkat(req, issue_flags);
8425 case IORING_OP_LINKAT:
8426 ret = io_linkat(req, issue_flags);
8428 case IORING_OP_MSG_RING:
8429 ret = io_msg_ring(req, issue_flags);
8431 case IORING_OP_FSETXATTR:
8432 ret = io_fsetxattr(req, issue_flags);
8434 case IORING_OP_SETXATTR:
8435 ret = io_setxattr(req, issue_flags);
8437 case IORING_OP_FGETXATTR:
8438 ret = io_fgetxattr(req, issue_flags);
8440 case IORING_OP_GETXATTR:
8441 ret = io_getxattr(req, issue_flags);
8443 case IORING_OP_SOCKET:
8444 ret = io_socket(req, issue_flags);
8446 case IORING_OP_URING_CMD:
8447 ret = io_uring_cmd(req, issue_flags);
8454 if (!def->audit_skip)
8455 audit_uring_exit(!ret, ret);
8458 revert_creds(creds);
8461 /* If the op doesn't have a file, we're not polling for it */
8462 if ((req->ctx->flags & IORING_SETUP_IOPOLL) && req->file)
8463 io_iopoll_req_issued(req, issue_flags);
8468 static struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
8470 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8472 req = io_put_req_find_next(req);
8473 return req ? &req->work : NULL;
8476 static void io_wq_submit_work(struct io_wq_work *work)
8478 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
8479 const struct io_op_def *def = &io_op_defs[req->opcode];
8480 unsigned int issue_flags = IO_URING_F_UNLOCKED;
8481 bool needs_poll = false;
8482 int ret = 0, err = -ECANCELED;
8484 /* one will be dropped by ->io_free_work() after returning to io-wq */
8485 if (!(req->flags & REQ_F_REFCOUNT))
8486 __io_req_set_refcount(req, 2);
8490 io_arm_ltimeout(req);
8492 /* either cancelled or io-wq is dying, so don't touch tctx->iowq */
8493 if (work->flags & IO_WQ_WORK_CANCEL) {
8495 io_req_task_queue_fail(req, err);
8498 if (!io_assign_file(req, issue_flags)) {
8500 work->flags |= IO_WQ_WORK_CANCEL;
8504 if (req->flags & REQ_F_FORCE_ASYNC) {
8505 bool opcode_poll = def->pollin || def->pollout;
8507 if (opcode_poll && file_can_poll(req->file)) {
8509 issue_flags |= IO_URING_F_NONBLOCK;
8514 ret = io_issue_sqe(req, issue_flags);
8518 * We can get EAGAIN for iopolled IO even though we're
8519 * forcing a sync submission from here, since we can't
8520 * wait for request slots on the block side.
8523 if (!(req->ctx->flags & IORING_SETUP_IOPOLL))
8529 if (io_arm_poll_handler(req, issue_flags) == IO_APOLL_OK)
8531 /* aborted or ready, in either case retry blocking */
8533 issue_flags &= ~IO_URING_F_NONBLOCK;
8536 /* avoid locking problems by failing it from a clean context */
8538 io_req_task_queue_fail(req, ret);
8541 static inline struct io_fixed_file *io_fixed_file_slot(struct io_file_table *table,
8544 return &table->files[i];
8547 static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
8550 struct io_fixed_file *slot = io_fixed_file_slot(&ctx->file_table, index);
8552 return (struct file *) (slot->file_ptr & FFS_MASK);
8555 static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file)
8557 unsigned long file_ptr = (unsigned long) file;
8559 file_ptr |= io_file_get_flags(file);
8560 file_slot->file_ptr = file_ptr;
8563 static inline struct file *io_file_get_fixed(struct io_kiocb *req, int fd,
8564 unsigned int issue_flags)
8566 struct io_ring_ctx *ctx = req->ctx;
8567 struct file *file = NULL;
8568 unsigned long file_ptr;
8570 io_ring_submit_lock(ctx, issue_flags);
8572 if (unlikely((unsigned int)fd >= ctx->nr_user_files))
8574 fd = array_index_nospec(fd, ctx->nr_user_files);
8575 file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr;
8576 file = (struct file *) (file_ptr & FFS_MASK);
8577 file_ptr &= ~FFS_MASK;
8578 /* mask in overlapping REQ_F and FFS bits */
8579 req->flags |= (file_ptr << REQ_F_SUPPORT_NOWAIT_BIT);
8580 io_req_set_rsrc_node(req, ctx, 0);
8581 WARN_ON_ONCE(file && !test_bit(fd, ctx->file_table.bitmap));
8583 io_ring_submit_unlock(ctx, issue_flags);
8587 static struct file *io_file_get_normal(struct io_kiocb *req, int fd)
8589 struct file *file = fget(fd);
8591 trace_io_uring_file_get(req->ctx, req, req->cqe.user_data, fd);
8593 /* we don't allow fixed io_uring files */
8594 if (file && file->f_op == &io_uring_fops)
8595 io_req_track_inflight(req);
8599 static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked)
8601 struct io_kiocb *prev = req->timeout.prev;
8605 if (!(req->task->flags & PF_EXITING)) {
8606 struct io_cancel_data cd = {
8608 .data = prev->cqe.user_data,
8611 ret = io_try_cancel(req, &cd);
8613 io_req_complete_post(req, ret ?: -ETIME, 0);
8616 io_req_complete_post(req, -ETIME, 0);
8620 static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
8622 struct io_timeout_data *data = container_of(timer,
8623 struct io_timeout_data, timer);
8624 struct io_kiocb *prev, *req = data->req;
8625 struct io_ring_ctx *ctx = req->ctx;
8626 unsigned long flags;
8628 spin_lock_irqsave(&ctx->timeout_lock, flags);
8629 prev = req->timeout.head;
8630 req->timeout.head = NULL;
8633 * We don't expect the list to be empty, that will only happen if we
8634 * race with the completion of the linked work.
8637 io_remove_next_linked(prev);
8638 if (!req_ref_inc_not_zero(prev))
8641 list_del(&req->timeout.list);
8642 req->timeout.prev = prev;
8643 spin_unlock_irqrestore(&ctx->timeout_lock, flags);
8645 req->io_task_work.func = io_req_task_link_timeout;
8646 io_req_task_work_add(req);
8647 return HRTIMER_NORESTART;
8650 static void io_queue_linked_timeout(struct io_kiocb *req)
8652 struct io_ring_ctx *ctx = req->ctx;
8654 spin_lock_irq(&ctx->timeout_lock);
8656 * If the back reference is NULL, then our linked request finished
8657 * before we got a chance to setup the timer
8659 if (req->timeout.head) {
8660 struct io_timeout_data *data = req->async_data;
8662 data->timer.function = io_link_timeout_fn;
8663 hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
8665 list_add_tail(&req->timeout.list, &ctx->ltimeout_list);
8667 spin_unlock_irq(&ctx->timeout_lock);
8668 /* drop submission reference */
8672 static void io_queue_async(struct io_kiocb *req, int ret)
8673 __must_hold(&req->ctx->uring_lock)
8675 struct io_kiocb *linked_timeout;
8677 if (ret != -EAGAIN || (req->flags & REQ_F_NOWAIT)) {
8678 io_req_complete_failed(req, ret);
8682 linked_timeout = io_prep_linked_timeout(req);
8684 switch (io_arm_poll_handler(req, 0)) {
8685 case IO_APOLL_READY:
8686 io_req_task_queue(req);
8688 case IO_APOLL_ABORTED:
8690 * Queued up for async execution, worker will release
8691 * submit reference when the iocb is actually submitted.
8693 io_kbuf_recycle(req, 0);
8694 io_queue_iowq(req, NULL);
8701 io_queue_linked_timeout(linked_timeout);
8704 static inline void io_queue_sqe(struct io_kiocb *req)
8705 __must_hold(&req->ctx->uring_lock)
8709 ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
8711 if (req->flags & REQ_F_COMPLETE_INLINE) {
8712 io_req_add_compl_list(req);
8716 * We async punt it if the file wasn't marked NOWAIT, or if the file
8717 * doesn't support non-blocking read/write attempts
8720 io_arm_ltimeout(req);
8722 io_queue_async(req, ret);
8725 static void io_queue_sqe_fallback(struct io_kiocb *req)
8726 __must_hold(&req->ctx->uring_lock)
8728 if (unlikely(req->flags & REQ_F_FAIL)) {
8730 * We don't submit, fail them all, for that replace hardlinks
8731 * with normal links. Extra REQ_F_LINK is tolerated.
8733 req->flags &= ~REQ_F_HARDLINK;
8734 req->flags |= REQ_F_LINK;
8735 io_req_complete_failed(req, req->cqe.res);
8736 } else if (unlikely(req->ctx->drain_active)) {
8739 int ret = io_req_prep_async(req);
8742 io_req_complete_failed(req, ret);
8744 io_queue_iowq(req, NULL);
8749 * Check SQE restrictions (opcode and flags).
8751 * Returns 'true' if SQE is allowed, 'false' otherwise.
8753 static inline bool io_check_restriction(struct io_ring_ctx *ctx,
8754 struct io_kiocb *req,
8755 unsigned int sqe_flags)
8757 if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
8760 if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
8761 ctx->restrictions.sqe_flags_required)
8764 if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
8765 ctx->restrictions.sqe_flags_required))
8771 static void io_init_req_drain(struct io_kiocb *req)
8773 struct io_ring_ctx *ctx = req->ctx;
8774 struct io_kiocb *head = ctx->submit_state.link.head;
8776 ctx->drain_active = true;
8779 * If we need to drain a request in the middle of a link, drain
8780 * the head request and the next request/link after the current
8781 * link. Considering sequential execution of links,
8782 * REQ_F_IO_DRAIN will be maintained for every request of our
8785 head->flags |= REQ_F_IO_DRAIN | REQ_F_FORCE_ASYNC;
8786 ctx->drain_next = true;
8790 static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
8791 const struct io_uring_sqe *sqe)
8792 __must_hold(&ctx->uring_lock)
8794 const struct io_op_def *def;
8795 unsigned int sqe_flags;
8799 /* req is partially pre-initialised, see io_preinit_req() */
8800 req->opcode = opcode = READ_ONCE(sqe->opcode);
8801 /* same numerical values with corresponding REQ_F_*, safe to copy */
8802 req->flags = sqe_flags = READ_ONCE(sqe->flags);
8803 req->cqe.user_data = READ_ONCE(sqe->user_data);
8805 req->rsrc_node = NULL;
8806 req->task = current;
8808 if (unlikely(opcode >= IORING_OP_LAST)) {
8812 def = &io_op_defs[opcode];
8813 if (unlikely(sqe_flags & ~SQE_COMMON_FLAGS)) {
8814 /* enforce forwards compatibility on users */
8815 if (sqe_flags & ~SQE_VALID_FLAGS)
8817 if (sqe_flags & IOSQE_BUFFER_SELECT) {
8818 if (!def->buffer_select)
8820 req->buf_index = READ_ONCE(sqe->buf_group);
8822 if (sqe_flags & IOSQE_CQE_SKIP_SUCCESS)
8823 ctx->drain_disabled = true;
8824 if (sqe_flags & IOSQE_IO_DRAIN) {
8825 if (ctx->drain_disabled)
8827 io_init_req_drain(req);
8830 if (unlikely(ctx->restricted || ctx->drain_active || ctx->drain_next)) {
8831 if (ctx->restricted && !io_check_restriction(ctx, req, sqe_flags))
8833 /* knock it to the slow queue path, will be drained there */
8834 if (ctx->drain_active)
8835 req->flags |= REQ_F_FORCE_ASYNC;
8836 /* if there is no link, we're at "next" request and need to drain */
8837 if (unlikely(ctx->drain_next) && !ctx->submit_state.link.head) {
8838 ctx->drain_next = false;
8839 ctx->drain_active = true;
8840 req->flags |= REQ_F_IO_DRAIN | REQ_F_FORCE_ASYNC;
8844 if (!def->ioprio && sqe->ioprio)
8846 if (!def->iopoll && (ctx->flags & IORING_SETUP_IOPOLL))
8849 if (def->needs_file) {
8850 struct io_submit_state *state = &ctx->submit_state;
8852 req->cqe.fd = READ_ONCE(sqe->fd);
8855 * Plug now if we have more than 2 IO left after this, and the
8856 * target is potentially a read/write to block based storage.
8858 if (state->need_plug && def->plug) {
8859 state->plug_started = true;
8860 state->need_plug = false;
8861 blk_start_plug_nr_ios(&state->plug, state->submit_nr);
8865 personality = READ_ONCE(sqe->personality);
8869 req->creds = xa_load(&ctx->personalities, personality);
8872 get_cred(req->creds);
8873 ret = security_uring_override_creds(req->creds);
8875 put_cred(req->creds);
8878 req->flags |= REQ_F_CREDS;
8881 return io_req_prep(req, sqe);
8884 static __cold int io_submit_fail_init(const struct io_uring_sqe *sqe,
8885 struct io_kiocb *req, int ret)
8887 struct io_ring_ctx *ctx = req->ctx;
8888 struct io_submit_link *link = &ctx->submit_state.link;
8889 struct io_kiocb *head = link->head;
8891 trace_io_uring_req_failed(sqe, ctx, req, ret);
8894 * Avoid breaking links in the middle as it renders links with SQPOLL
8895 * unusable. Instead of failing eagerly, continue assembling the link if
8896 * applicable and mark the head with REQ_F_FAIL. The link flushing code
8897 * should find the flag and handle the rest.
8899 req_fail_link_node(req, ret);
8900 if (head && !(head->flags & REQ_F_FAIL))
8901 req_fail_link_node(head, -ECANCELED);
8903 if (!(req->flags & IO_REQ_LINK_FLAGS)) {
8905 link->last->link = req;
8909 io_queue_sqe_fallback(req);
8914 link->last->link = req;
8921 static inline int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
8922 const struct io_uring_sqe *sqe)
8923 __must_hold(&ctx->uring_lock)
8925 struct io_submit_link *link = &ctx->submit_state.link;
8928 ret = io_init_req(ctx, req, sqe);
8930 return io_submit_fail_init(sqe, req, ret);
8932 /* don't need @sqe from now on */
8933 trace_io_uring_submit_sqe(ctx, req, req->cqe.user_data, req->opcode,
8935 ctx->flags & IORING_SETUP_SQPOLL);
8938 * If we already have a head request, queue this one for async
8939 * submittal once the head completes. If we don't have a head but
8940 * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
8941 * submitted sync once the chain is complete. If none of those
8942 * conditions are true (normal request), then just queue it.
8944 if (unlikely(link->head)) {
8945 ret = io_req_prep_async(req);
8947 return io_submit_fail_init(sqe, req, ret);
8949 trace_io_uring_link(ctx, req, link->head);
8950 link->last->link = req;
8953 if (req->flags & IO_REQ_LINK_FLAGS)
8955 /* last request of the link, flush it */
8958 if (req->flags & (REQ_F_FORCE_ASYNC | REQ_F_FAIL))
8961 } else if (unlikely(req->flags & (IO_REQ_LINK_FLAGS |
8962 REQ_F_FORCE_ASYNC | REQ_F_FAIL))) {
8963 if (req->flags & IO_REQ_LINK_FLAGS) {
8968 io_queue_sqe_fallback(req);
8978 * Batched submission is done, ensure local IO is flushed out.
8980 static void io_submit_state_end(struct io_ring_ctx *ctx)
8982 struct io_submit_state *state = &ctx->submit_state;
8984 if (unlikely(state->link.head))
8985 io_queue_sqe_fallback(state->link.head);
8986 /* flush only after queuing links as they can generate completions */
8987 io_submit_flush_completions(ctx);
8988 if (state->plug_started)
8989 blk_finish_plug(&state->plug);
8993 * Start submission side cache.
8995 static void io_submit_state_start(struct io_submit_state *state,
8996 unsigned int max_ios)
8998 state->plug_started = false;
8999 state->need_plug = max_ios > 2;
9000 state->submit_nr = max_ios;
9001 /* set only head, no need to init link_last in advance */
9002 state->link.head = NULL;
9005 static void io_commit_sqring(struct io_ring_ctx *ctx)
9007 struct io_rings *rings = ctx->rings;
9010 * Ensure any loads from the SQEs are done at this point,
9011 * since once we write the new head, the application could
9012 * write new data to them.
9014 smp_store_release(&rings->sq.head, ctx->cached_sq_head);
9018 * Fetch an sqe, if one is available. Note this returns a pointer to memory
9019 * that is mapped by userspace. This means that care needs to be taken to
9020 * ensure that reads are stable, as we cannot rely on userspace always
9021 * being a good citizen. If members of the sqe are validated and then later
9022 * used, it's important that those reads are done through READ_ONCE() to
9023 * prevent a re-load down the line.
9025 static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
9027 unsigned head, mask = ctx->sq_entries - 1;
9028 unsigned sq_idx = ctx->cached_sq_head++ & mask;
9031 * The cached sq head (or cq tail) serves two purposes:
9033 * 1) allows us to batch the cost of updating the user visible
9035 * 2) allows the kernel side to track the head on its own, even
9036 * though the application is the one updating it.
9038 head = READ_ONCE(ctx->sq_array[sq_idx]);
9039 if (likely(head < ctx->sq_entries)) {
9040 /* double index for 128-byte SQEs, twice as long */
9041 if (ctx->flags & IORING_SETUP_SQE128)
9043 return &ctx->sq_sqes[head];
9046 /* drop invalid entries */
9048 WRITE_ONCE(ctx->rings->sq_dropped,
9049 READ_ONCE(ctx->rings->sq_dropped) + 1);
9053 static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
9054 __must_hold(&ctx->uring_lock)
9056 unsigned int entries = io_sqring_entries(ctx);
9060 if (unlikely(!entries))
9062 /* make sure SQ entry isn't read before tail */
9063 ret = left = min3(nr, ctx->sq_entries, entries);
9064 io_get_task_refs(left);
9065 io_submit_state_start(&ctx->submit_state, left);
9068 const struct io_uring_sqe *sqe;
9069 struct io_kiocb *req;
9071 if (unlikely(!io_alloc_req_refill(ctx)))
9073 req = io_alloc_req(ctx);
9074 sqe = io_get_sqe(ctx);
9075 if (unlikely(!sqe)) {
9076 io_req_add_to_cache(req, ctx);
9081 * Continue submitting even for sqe failure if the
9082 * ring was setup with IORING_SETUP_SUBMIT_ALL
9084 if (unlikely(io_submit_sqe(ctx, req, sqe)) &&
9085 !(ctx->flags & IORING_SETUP_SUBMIT_ALL)) {
9091 if (unlikely(left)) {
9093 /* try again if it submitted nothing and can't allocate a req */
9094 if (!ret && io_req_cache_empty(ctx))
9096 current->io_uring->cached_refs += left;
9099 io_submit_state_end(ctx);
9100 /* Commit SQ ring head once we've consumed and submitted all SQEs */
9101 io_commit_sqring(ctx);
9105 static inline bool io_sqd_events_pending(struct io_sq_data *sqd)
9107 return READ_ONCE(sqd->state);
9110 static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
9112 unsigned int to_submit;
9115 to_submit = io_sqring_entries(ctx);
9116 /* if we're handling multiple rings, cap submit size for fairness */
9117 if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE)
9118 to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;
9120 if (!wq_list_empty(&ctx->iopoll_list) || to_submit) {
9121 const struct cred *creds = NULL;
9123 if (ctx->sq_creds != current_cred())
9124 creds = override_creds(ctx->sq_creds);
9126 mutex_lock(&ctx->uring_lock);
9127 if (!wq_list_empty(&ctx->iopoll_list))
9128 io_do_iopoll(ctx, true);
9131 * Don't submit if refs are dying, good for io_uring_register(),
9132 * but also it is relied upon by io_ring_exit_work()
9134 if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
9135 !(ctx->flags & IORING_SETUP_R_DISABLED))
9136 ret = io_submit_sqes(ctx, to_submit);
9137 mutex_unlock(&ctx->uring_lock);
9139 if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
9140 wake_up(&ctx->sqo_sq_wait);
9142 revert_creds(creds);
9148 static __cold void io_sqd_update_thread_idle(struct io_sq_data *sqd)
9150 struct io_ring_ctx *ctx;
9151 unsigned sq_thread_idle = 0;
9153 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
9154 sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle);
9155 sqd->sq_thread_idle = sq_thread_idle;
9158 static bool io_sqd_handle_event(struct io_sq_data *sqd)
9160 bool did_sig = false;
9161 struct ksignal ksig;
9163 if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
9164 signal_pending(current)) {
9165 mutex_unlock(&sqd->lock);
9166 if (signal_pending(current))
9167 did_sig = get_signal(&ksig);
9169 mutex_lock(&sqd->lock);
9171 return did_sig || test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
9174 static int io_sq_thread(void *data)
9176 struct io_sq_data *sqd = data;
9177 struct io_ring_ctx *ctx;
9178 unsigned long timeout = 0;
9179 char buf[TASK_COMM_LEN];
9182 snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
9183 set_task_comm(current, buf);
9185 if (sqd->sq_cpu != -1)
9186 set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
9188 set_cpus_allowed_ptr(current, cpu_online_mask);
9189 current->flags |= PF_NO_SETAFFINITY;
9191 audit_alloc_kernel(current);
9193 mutex_lock(&sqd->lock);
9195 bool cap_entries, sqt_spin = false;
9197 if (io_sqd_events_pending(sqd) || signal_pending(current)) {
9198 if (io_sqd_handle_event(sqd))
9200 timeout = jiffies + sqd->sq_thread_idle;
9203 cap_entries = !list_is_singular(&sqd->ctx_list);
9204 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
9205 int ret = __io_sq_thread(ctx, cap_entries);
9207 if (!sqt_spin && (ret > 0 || !wq_list_empty(&ctx->iopoll_list)))
9210 if (io_run_task_work())
9213 if (sqt_spin || !time_after(jiffies, timeout)) {
9216 timeout = jiffies + sqd->sq_thread_idle;
9220 prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
9221 if (!io_sqd_events_pending(sqd) && !task_work_pending(current)) {
9222 bool needs_sched = true;
9224 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
9225 atomic_or(IORING_SQ_NEED_WAKEUP,
9226 &ctx->rings->sq_flags);
9227 if ((ctx->flags & IORING_SETUP_IOPOLL) &&
9228 !wq_list_empty(&ctx->iopoll_list)) {
9229 needs_sched = false;
9234 * Ensure the store of the wakeup flag is not
9235 * reordered with the load of the SQ tail
9237 smp_mb__after_atomic();
9239 if (io_sqring_entries(ctx)) {
9240 needs_sched = false;
9246 mutex_unlock(&sqd->lock);
9248 mutex_lock(&sqd->lock);
9250 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
9251 atomic_andnot(IORING_SQ_NEED_WAKEUP,
9252 &ctx->rings->sq_flags);
9255 finish_wait(&sqd->wait, &wait);
9256 timeout = jiffies + sqd->sq_thread_idle;
9259 io_uring_cancel_generic(true, sqd);
9261 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
9262 atomic_or(IORING_SQ_NEED_WAKEUP, &ctx->rings->sq_flags);
9264 mutex_unlock(&sqd->lock);
9266 audit_free(current);
9268 complete(&sqd->exited);
9272 struct io_wait_queue {
9273 struct wait_queue_entry wq;
9274 struct io_ring_ctx *ctx;
9276 unsigned nr_timeouts;
9279 static inline bool io_should_wake(struct io_wait_queue *iowq)
9281 struct io_ring_ctx *ctx = iowq->ctx;
9282 int dist = ctx->cached_cq_tail - (int) iowq->cq_tail;
9285 * Wake up if we have enough events, or if a timeout occurred since we
9286 * started waiting. For timeouts, we always want to return to userspace,
9287 * regardless of event count.
9289 return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
9292 static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
9293 int wake_flags, void *key)
9295 struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
9299 * Cannot safely flush overflowed CQEs from here, ensure we wake up
9300 * the task, and the next invocation will do it.
9302 if (io_should_wake(iowq) ||
9303 test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &iowq->ctx->check_cq))
9304 return autoremove_wake_function(curr, mode, wake_flags, key);
9308 static int io_run_task_work_sig(void)
9310 if (io_run_task_work())
9312 if (test_thread_flag(TIF_NOTIFY_SIGNAL))
9313 return -ERESTARTSYS;
9314 if (task_sigpending(current))
9319 /* when returns >0, the caller should retry */
9320 static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
9321 struct io_wait_queue *iowq,
9325 unsigned long check_cq;
9327 /* make sure we run task_work before checking for signals */
9328 ret = io_run_task_work_sig();
9329 if (ret || io_should_wake(iowq))
9331 check_cq = READ_ONCE(ctx->check_cq);
9332 /* let the caller flush overflows, retry */
9333 if (check_cq & BIT(IO_CHECK_CQ_OVERFLOW_BIT))
9335 if (unlikely(check_cq & BIT(IO_CHECK_CQ_DROPPED_BIT)))
9337 if (!schedule_hrtimeout(&timeout, HRTIMER_MODE_ABS))
9343 * Wait until events become available, if we don't already have some. The
9344 * application must reap them itself, as they reside on the shared cq ring.
9346 static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
9347 const sigset_t __user *sig, size_t sigsz,
9348 struct __kernel_timespec __user *uts)
9350 struct io_wait_queue iowq;
9351 struct io_rings *rings = ctx->rings;
9352 ktime_t timeout = KTIME_MAX;
9356 io_cqring_overflow_flush(ctx);
9357 if (io_cqring_events(ctx) >= min_events)
9359 if (!io_run_task_work())
9364 #ifdef CONFIG_COMPAT
9365 if (in_compat_syscall())
9366 ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
9370 ret = set_user_sigmask(sig, sigsz);
9377 struct timespec64 ts;
9379 if (get_timespec64(&ts, uts))
9381 timeout = ktime_add_ns(timespec64_to_ktime(ts), ktime_get_ns());
9384 init_waitqueue_func_entry(&iowq.wq, io_wake_function);
9385 iowq.wq.private = current;
9386 INIT_LIST_HEAD(&iowq.wq.entry);
9388 iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
9389 iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events;
9391 trace_io_uring_cqring_wait(ctx, min_events);
9393 /* if we can't even flush overflow, don't wait for more */
9394 if (!io_cqring_overflow_flush(ctx)) {
9398 prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq,
9399 TASK_INTERRUPTIBLE);
9400 ret = io_cqring_wait_schedule(ctx, &iowq, timeout);
9404 finish_wait(&ctx->cq_wait, &iowq.wq);
9405 restore_saved_sigmask_unless(ret == -EINTR);
9407 return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
9410 static void io_free_page_table(void **table, size_t size)
9412 unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
9414 for (i = 0; i < nr_tables; i++)
9419 static __cold void **io_alloc_page_table(size_t size)
9421 unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
9422 size_t init_size = size;
9425 table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT);
9429 for (i = 0; i < nr_tables; i++) {
9430 unsigned int this_size = min_t(size_t, size, PAGE_SIZE);
9432 table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT);
9434 io_free_page_table(table, init_size);
9442 static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node)
9444 percpu_ref_exit(&ref_node->refs);
9448 static __cold void io_rsrc_node_ref_zero(struct percpu_ref *ref)
9450 struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs);
9451 struct io_ring_ctx *ctx = node->rsrc_data->ctx;
9452 unsigned long flags;
9453 bool first_add = false;
9454 unsigned long delay = HZ;
9456 spin_lock_irqsave(&ctx->rsrc_ref_lock, flags);
9459 /* if we are mid-quiesce then do not delay */
9460 if (node->rsrc_data->quiesce)
9463 while (!list_empty(&ctx->rsrc_ref_list)) {
9464 node = list_first_entry(&ctx->rsrc_ref_list,
9465 struct io_rsrc_node, node);
9466 /* recycle ref nodes in order */
9469 list_del(&node->node);
9470 first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist);
9472 spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags);
9475 mod_delayed_work(system_wq, &ctx->rsrc_put_work, delay);
9478 static struct io_rsrc_node *io_rsrc_node_alloc(void)
9480 struct io_rsrc_node *ref_node;
9482 ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
9486 if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
9491 INIT_LIST_HEAD(&ref_node->node);
9492 INIT_LIST_HEAD(&ref_node->rsrc_list);
9493 ref_node->done = false;
9497 static void io_rsrc_node_switch(struct io_ring_ctx *ctx,
9498 struct io_rsrc_data *data_to_kill)
9499 __must_hold(&ctx->uring_lock)
9501 WARN_ON_ONCE(!ctx->rsrc_backup_node);
9502 WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node);
9504 io_rsrc_refs_drop(ctx);
9507 struct io_rsrc_node *rsrc_node = ctx->rsrc_node;
9509 rsrc_node->rsrc_data = data_to_kill;
9510 spin_lock_irq(&ctx->rsrc_ref_lock);
9511 list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list);
9512 spin_unlock_irq(&ctx->rsrc_ref_lock);
9514 atomic_inc(&data_to_kill->refs);
9515 percpu_ref_kill(&rsrc_node->refs);
9516 ctx->rsrc_node = NULL;
9519 if (!ctx->rsrc_node) {
9520 ctx->rsrc_node = ctx->rsrc_backup_node;
9521 ctx->rsrc_backup_node = NULL;
9525 static int io_rsrc_node_switch_start(struct io_ring_ctx *ctx)
9527 if (ctx->rsrc_backup_node)
9529 ctx->rsrc_backup_node = io_rsrc_node_alloc();
9530 return ctx->rsrc_backup_node ? 0 : -ENOMEM;
9533 static __cold int io_rsrc_ref_quiesce(struct io_rsrc_data *data,
9534 struct io_ring_ctx *ctx)
9538 /* As we may drop ->uring_lock, other task may have started quiesce */
9542 data->quiesce = true;
9544 ret = io_rsrc_node_switch_start(ctx);
9547 io_rsrc_node_switch(ctx, data);
9549 /* kill initial ref, already quiesced if zero */
9550 if (atomic_dec_and_test(&data->refs))
9552 mutex_unlock(&ctx->uring_lock);
9553 flush_delayed_work(&ctx->rsrc_put_work);
9554 ret = wait_for_completion_interruptible(&data->done);
9556 mutex_lock(&ctx->uring_lock);
9557 if (atomic_read(&data->refs) > 0) {
9559 * it has been revived by another thread while
9562 mutex_unlock(&ctx->uring_lock);
9568 atomic_inc(&data->refs);
9569 /* wait for all works potentially completing data->done */
9570 flush_delayed_work(&ctx->rsrc_put_work);
9571 reinit_completion(&data->done);
9573 ret = io_run_task_work_sig();
9574 mutex_lock(&ctx->uring_lock);
9576 data->quiesce = false;
9581 static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
9583 unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
9584 unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
9586 return &data->tags[table_idx][off];
9589 static void io_rsrc_data_free(struct io_rsrc_data *data)
9591 size_t size = data->nr * sizeof(data->tags[0][0]);
9594 io_free_page_table((void **)data->tags, size);
9598 static __cold int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put,
9599 u64 __user *utags, unsigned nr,
9600 struct io_rsrc_data **pdata)
9602 struct io_rsrc_data *data;
9606 data = kzalloc(sizeof(*data), GFP_KERNEL);
9609 data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0]));
9617 data->do_put = do_put;
9620 for (i = 0; i < nr; i++) {
9621 u64 *tag_slot = io_get_tag_slot(data, i);
9623 if (copy_from_user(tag_slot, &utags[i],
9629 atomic_set(&data->refs, 1);
9630 init_completion(&data->done);
9634 io_rsrc_data_free(data);
9638 static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
9640 table->files = kvcalloc(nr_files, sizeof(table->files[0]),
9641 GFP_KERNEL_ACCOUNT);
9642 if (unlikely(!table->files))
9645 table->bitmap = bitmap_zalloc(nr_files, GFP_KERNEL_ACCOUNT);
9646 if (unlikely(!table->bitmap)) {
9647 kvfree(table->files);
9654 static void io_free_file_tables(struct io_file_table *table)
9656 kvfree(table->files);
9657 bitmap_free(table->bitmap);
9658 table->files = NULL;
9659 table->bitmap = NULL;
9662 static inline void io_file_bitmap_set(struct io_file_table *table, int bit)
9664 WARN_ON_ONCE(test_bit(bit, table->bitmap));
9665 __set_bit(bit, table->bitmap);
9666 table->alloc_hint = bit + 1;
9669 static inline void io_file_bitmap_clear(struct io_file_table *table, int bit)
9671 __clear_bit(bit, table->bitmap);
9672 table->alloc_hint = bit;
9675 static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
9677 #if !defined(IO_URING_SCM_ALL)
9680 for (i = 0; i < ctx->nr_user_files; i++) {
9681 struct file *file = io_file_from_index(ctx, i);
9685 if (io_fixed_file_slot(&ctx->file_table, i)->file_ptr & FFS_SCM)
9687 io_file_bitmap_clear(&ctx->file_table, i);
9692 #if defined(CONFIG_UNIX)
9693 if (ctx->ring_sock) {
9694 struct sock *sock = ctx->ring_sock->sk;
9695 struct sk_buff *skb;
9697 while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
9701 io_free_file_tables(&ctx->file_table);
9702 io_rsrc_data_free(ctx->file_data);
9703 ctx->file_data = NULL;
9704 ctx->nr_user_files = 0;
9707 static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
9709 unsigned nr = ctx->nr_user_files;
9712 if (!ctx->file_data)
9716 * Quiesce may unlock ->uring_lock, and while it's not held
9717 * prevent new requests using the table.
9719 ctx->nr_user_files = 0;
9720 ret = io_rsrc_ref_quiesce(ctx->file_data, ctx);
9721 ctx->nr_user_files = nr;
9723 __io_sqe_files_unregister(ctx);
9727 static void io_sq_thread_unpark(struct io_sq_data *sqd)
9728 __releases(&sqd->lock)
9730 WARN_ON_ONCE(sqd->thread == current);
9733 * Do the dance but not conditional clear_bit() because it'd race with
9734 * other threads incrementing park_pending and setting the bit.
9736 clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
9737 if (atomic_dec_return(&sqd->park_pending))
9738 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
9739 mutex_unlock(&sqd->lock);
9742 static void io_sq_thread_park(struct io_sq_data *sqd)
9743 __acquires(&sqd->lock)
9745 WARN_ON_ONCE(sqd->thread == current);
9747 atomic_inc(&sqd->park_pending);
9748 set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
9749 mutex_lock(&sqd->lock);
9751 wake_up_process(sqd->thread);
9754 static void io_sq_thread_stop(struct io_sq_data *sqd)
9756 WARN_ON_ONCE(sqd->thread == current);
9757 WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state));
9759 set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
9760 mutex_lock(&sqd->lock);
9762 wake_up_process(sqd->thread);
9763 mutex_unlock(&sqd->lock);
9764 wait_for_completion(&sqd->exited);
9767 static void io_put_sq_data(struct io_sq_data *sqd)
9769 if (refcount_dec_and_test(&sqd->refs)) {
9770 WARN_ON_ONCE(atomic_read(&sqd->park_pending));
9772 io_sq_thread_stop(sqd);
9777 static void io_sq_thread_finish(struct io_ring_ctx *ctx)
9779 struct io_sq_data *sqd = ctx->sq_data;
9782 io_sq_thread_park(sqd);
9783 list_del_init(&ctx->sqd_list);
9784 io_sqd_update_thread_idle(sqd);
9785 io_sq_thread_unpark(sqd);
9787 io_put_sq_data(sqd);
9788 ctx->sq_data = NULL;
9792 static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
9794 struct io_ring_ctx *ctx_attach;
9795 struct io_sq_data *sqd;
9798 f = fdget(p->wq_fd);
9800 return ERR_PTR(-ENXIO);
9801 if (f.file->f_op != &io_uring_fops) {
9803 return ERR_PTR(-EINVAL);
9806 ctx_attach = f.file->private_data;
9807 sqd = ctx_attach->sq_data;
9810 return ERR_PTR(-EINVAL);
9812 if (sqd->task_tgid != current->tgid) {
9814 return ERR_PTR(-EPERM);
9817 refcount_inc(&sqd->refs);
9822 static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
9825 struct io_sq_data *sqd;
9828 if (p->flags & IORING_SETUP_ATTACH_WQ) {
9829 sqd = io_attach_sq_data(p);
9834 /* fall through for EPERM case, setup new sqd/task */
9835 if (PTR_ERR(sqd) != -EPERM)
9839 sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
9841 return ERR_PTR(-ENOMEM);
9843 atomic_set(&sqd->park_pending, 0);
9844 refcount_set(&sqd->refs, 1);
9845 INIT_LIST_HEAD(&sqd->ctx_list);
9846 mutex_init(&sqd->lock);
9847 init_waitqueue_head(&sqd->wait);
9848 init_completion(&sqd->exited);
9853 * Ensure the UNIX gc is aware of our file set, so we are certain that
9854 * the io_uring can be safely unregistered on process exit, even if we have
9855 * loops in the file referencing. We account only files that can hold other
9856 * files because otherwise they can't form a loop and so are not interesting
9859 static int io_scm_file_account(struct io_ring_ctx *ctx, struct file *file)
9861 #if defined(CONFIG_UNIX)
9862 struct sock *sk = ctx->ring_sock->sk;
9863 struct sk_buff_head *head = &sk->sk_receive_queue;
9864 struct scm_fp_list *fpl;
9865 struct sk_buff *skb;
9867 if (likely(!io_file_need_scm(file)))
9871 * See if we can merge this file into an existing skb SCM_RIGHTS
9872 * file set. If there's no room, fall back to allocating a new skb
9873 * and filling it in.
9875 spin_lock_irq(&head->lock);
9876 skb = skb_peek(head);
9877 if (skb && UNIXCB(skb).fp->count < SCM_MAX_FD)
9878 __skb_unlink(skb, head);
9881 spin_unlock_irq(&head->lock);
9884 fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
9888 skb = alloc_skb(0, GFP_KERNEL);
9894 fpl->user = get_uid(current_user());
9895 fpl->max = SCM_MAX_FD;
9898 UNIXCB(skb).fp = fpl;
9900 skb->destructor = unix_destruct_scm;
9901 refcount_add(skb->truesize, &sk->sk_wmem_alloc);
9904 fpl = UNIXCB(skb).fp;
9905 fpl->fp[fpl->count++] = get_file(file);
9906 unix_inflight(fpl->user, file);
9907 skb_queue_head(head, skb);
9913 static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
9915 struct file *file = prsrc->file;
9916 #if defined(CONFIG_UNIX)
9917 struct sock *sock = ctx->ring_sock->sk;
9918 struct sk_buff_head list, *head = &sock->sk_receive_queue;
9919 struct sk_buff *skb;
9922 if (!io_file_need_scm(file)) {
9927 __skb_queue_head_init(&list);
9930 * Find the skb that holds this file in its SCM_RIGHTS. When found,
9931 * remove this entry and rearrange the file array.
9933 skb = skb_dequeue(head);
9935 struct scm_fp_list *fp;
9937 fp = UNIXCB(skb).fp;
9938 for (i = 0; i < fp->count; i++) {
9941 if (fp->fp[i] != file)
9944 unix_notinflight(fp->user, fp->fp[i]);
9945 left = fp->count - 1 - i;
9947 memmove(&fp->fp[i], &fp->fp[i + 1],
9948 left * sizeof(struct file *));
9955 __skb_queue_tail(&list, skb);
9965 __skb_queue_tail(&list, skb);
9967 skb = skb_dequeue(head);
9970 if (skb_peek(&list)) {
9971 spin_lock_irq(&head->lock);
9972 while ((skb = __skb_dequeue(&list)) != NULL)
9973 __skb_queue_tail(head, skb);
9974 spin_unlock_irq(&head->lock);
9981 static void __io_rsrc_put_work(struct io_rsrc_node *ref_node)
9983 struct io_rsrc_data *rsrc_data = ref_node->rsrc_data;
9984 struct io_ring_ctx *ctx = rsrc_data->ctx;
9985 struct io_rsrc_put *prsrc, *tmp;
9987 list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
9988 list_del(&prsrc->list);
9991 if (ctx->flags & IORING_SETUP_IOPOLL)
9992 mutex_lock(&ctx->uring_lock);
9994 spin_lock(&ctx->completion_lock);
9995 io_fill_cqe_aux(ctx, prsrc->tag, 0, 0);
9996 io_commit_cqring(ctx);
9997 spin_unlock(&ctx->completion_lock);
9998 io_cqring_ev_posted(ctx);
10000 if (ctx->flags & IORING_SETUP_IOPOLL)
10001 mutex_unlock(&ctx->uring_lock);
10004 rsrc_data->do_put(ctx, prsrc);
10008 io_rsrc_node_destroy(ref_node);
10009 if (atomic_dec_and_test(&rsrc_data->refs))
10010 complete(&rsrc_data->done);
10013 static void io_rsrc_put_work(struct work_struct *work)
10015 struct io_ring_ctx *ctx;
10016 struct llist_node *node;
10018 ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
10019 node = llist_del_all(&ctx->rsrc_put_llist);
10022 struct io_rsrc_node *ref_node;
10023 struct llist_node *next = node->next;
10025 ref_node = llist_entry(node, struct io_rsrc_node, llist);
10026 __io_rsrc_put_work(ref_node);
10031 static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
10032 unsigned nr_args, u64 __user *tags)
10034 __s32 __user *fds = (__s32 __user *) arg;
10039 if (ctx->file_data)
10043 if (nr_args > IORING_MAX_FIXED_FILES)
10045 if (nr_args > rlimit(RLIMIT_NOFILE))
10047 ret = io_rsrc_node_switch_start(ctx);
10050 ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args,
10055 if (!io_alloc_file_tables(&ctx->file_table, nr_args)) {
10056 io_rsrc_data_free(ctx->file_data);
10057 ctx->file_data = NULL;
10061 for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
10062 struct io_fixed_file *file_slot;
10064 if (fds && copy_from_user(&fd, &fds[i], sizeof(fd))) {
10068 /* allow sparse sets */
10069 if (!fds || fd == -1) {
10071 if (unlikely(*io_get_tag_slot(ctx->file_data, i)))
10078 if (unlikely(!file))
10082 * Don't allow io_uring instances to be registered. If UNIX
10083 * isn't enabled, then this causes a reference cycle and this
10084 * instance can never get freed. If UNIX is enabled we'll
10085 * handle it just fine, but there's still no point in allowing
10086 * a ring fd as it doesn't support regular read/write anyway.
10088 if (file->f_op == &io_uring_fops) {
10092 ret = io_scm_file_account(ctx, file);
10097 file_slot = io_fixed_file_slot(&ctx->file_table, i);
10098 io_fixed_file_set(file_slot, file);
10099 io_file_bitmap_set(&ctx->file_table, i);
10102 io_rsrc_node_switch(ctx, NULL);
10105 __io_sqe_files_unregister(ctx);
10109 static int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
10110 struct io_rsrc_node *node, void *rsrc)
10112 u64 *tag_slot = io_get_tag_slot(data, idx);
10113 struct io_rsrc_put *prsrc;
10115 prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
10119 prsrc->tag = *tag_slot;
10121 prsrc->rsrc = rsrc;
10122 list_add(&prsrc->list, &node->rsrc_list);
10126 static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
10127 unsigned int issue_flags, u32 slot_index)
10128 __must_hold(&req->ctx->uring_lock)
10130 struct io_ring_ctx *ctx = req->ctx;
10131 bool needs_switch = false;
10132 struct io_fixed_file *file_slot;
10135 if (file->f_op == &io_uring_fops)
10137 if (!ctx->file_data)
10139 if (slot_index >= ctx->nr_user_files)
10142 slot_index = array_index_nospec(slot_index, ctx->nr_user_files);
10143 file_slot = io_fixed_file_slot(&ctx->file_table, slot_index);
10145 if (file_slot->file_ptr) {
10146 struct file *old_file;
10148 ret = io_rsrc_node_switch_start(ctx);
10152 old_file = (struct file *)(file_slot->file_ptr & FFS_MASK);
10153 ret = io_queue_rsrc_removal(ctx->file_data, slot_index,
10154 ctx->rsrc_node, old_file);
10157 file_slot->file_ptr = 0;
10158 io_file_bitmap_clear(&ctx->file_table, slot_index);
10159 needs_switch = true;
10162 ret = io_scm_file_account(ctx, file);
10164 *io_get_tag_slot(ctx->file_data, slot_index) = 0;
10165 io_fixed_file_set(file_slot, file);
10166 io_file_bitmap_set(&ctx->file_table, slot_index);
10170 io_rsrc_node_switch(ctx, ctx->file_data);
10176 static int __io_close_fixed(struct io_kiocb *req, unsigned int issue_flags,
10177 unsigned int offset)
10179 struct io_ring_ctx *ctx = req->ctx;
10180 struct io_fixed_file *file_slot;
10184 io_ring_submit_lock(ctx, issue_flags);
10186 if (unlikely(!ctx->file_data))
10189 if (offset >= ctx->nr_user_files)
10191 ret = io_rsrc_node_switch_start(ctx);
10195 offset = array_index_nospec(offset, ctx->nr_user_files);
10196 file_slot = io_fixed_file_slot(&ctx->file_table, offset);
10198 if (!file_slot->file_ptr)
10201 file = (struct file *)(file_slot->file_ptr & FFS_MASK);
10202 ret = io_queue_rsrc_removal(ctx->file_data, offset, ctx->rsrc_node, file);
10206 file_slot->file_ptr = 0;
10207 io_file_bitmap_clear(&ctx->file_table, offset);
10208 io_rsrc_node_switch(ctx, ctx->file_data);
10211 io_ring_submit_unlock(ctx, issue_flags);
10215 static inline int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags)
10217 return __io_close_fixed(req, issue_flags, req->close.file_slot - 1);
10220 static int __io_sqe_files_update(struct io_ring_ctx *ctx,
10221 struct io_uring_rsrc_update2 *up,
10224 u64 __user *tags = u64_to_user_ptr(up->tags);
10225 __s32 __user *fds = u64_to_user_ptr(up->data);
10226 struct io_rsrc_data *data = ctx->file_data;
10227 struct io_fixed_file *file_slot;
10229 int fd, i, err = 0;
10231 bool needs_switch = false;
10233 if (!ctx->file_data)
10235 if (up->offset + nr_args > ctx->nr_user_files)
10238 for (done = 0; done < nr_args; done++) {
10241 if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) ||
10242 copy_from_user(&fd, &fds[done], sizeof(fd))) {
10246 if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) {
10250 if (fd == IORING_REGISTER_FILES_SKIP)
10253 i = array_index_nospec(up->offset + done, ctx->nr_user_files);
10254 file_slot = io_fixed_file_slot(&ctx->file_table, i);
10256 if (file_slot->file_ptr) {
10257 file = (struct file *)(file_slot->file_ptr & FFS_MASK);
10258 err = io_queue_rsrc_removal(data, i, ctx->rsrc_node, file);
10261 file_slot->file_ptr = 0;
10262 io_file_bitmap_clear(&ctx->file_table, i);
10263 needs_switch = true;
10272 * Don't allow io_uring instances to be registered. If
10273 * UNIX isn't enabled, then this causes a reference
10274 * cycle and this instance can never get freed. If UNIX
10275 * is enabled we'll handle it just fine, but there's
10276 * still no point in allowing a ring fd as it doesn't
10277 * support regular read/write anyway.
10279 if (file->f_op == &io_uring_fops) {
10284 err = io_scm_file_account(ctx, file);
10289 *io_get_tag_slot(data, i) = tag;
10290 io_fixed_file_set(file_slot, file);
10291 io_file_bitmap_set(&ctx->file_table, i);
10296 io_rsrc_node_switch(ctx, data);
10297 return done ? done : err;
10300 static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
10301 struct task_struct *task)
10303 struct io_wq_hash *hash;
10304 struct io_wq_data data;
10305 unsigned int concurrency;
10307 mutex_lock(&ctx->uring_lock);
10308 hash = ctx->hash_map;
10310 hash = kzalloc(sizeof(*hash), GFP_KERNEL);
10312 mutex_unlock(&ctx->uring_lock);
10313 return ERR_PTR(-ENOMEM);
10315 refcount_set(&hash->refs, 1);
10316 init_waitqueue_head(&hash->wait);
10317 ctx->hash_map = hash;
10319 mutex_unlock(&ctx->uring_lock);
10323 data.free_work = io_wq_free_work;
10324 data.do_work = io_wq_submit_work;
10326 /* Do QD, or 4 * CPUS, whatever is smallest */
10327 concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
10329 return io_wq_create(concurrency, &data);
10332 static __cold int io_uring_alloc_task_context(struct task_struct *task,
10333 struct io_ring_ctx *ctx)
10335 struct io_uring_task *tctx;
10338 tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
10339 if (unlikely(!tctx))
10342 tctx->registered_rings = kcalloc(IO_RINGFD_REG_MAX,
10343 sizeof(struct file *), GFP_KERNEL);
10344 if (unlikely(!tctx->registered_rings)) {
10349 ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
10350 if (unlikely(ret)) {
10351 kfree(tctx->registered_rings);
10356 tctx->io_wq = io_init_wq_offload(ctx, task);
10357 if (IS_ERR(tctx->io_wq)) {
10358 ret = PTR_ERR(tctx->io_wq);
10359 percpu_counter_destroy(&tctx->inflight);
10360 kfree(tctx->registered_rings);
10365 xa_init(&tctx->xa);
10366 init_waitqueue_head(&tctx->wait);
10367 atomic_set(&tctx->in_idle, 0);
10368 atomic_set(&tctx->inflight_tracked, 0);
10369 task->io_uring = tctx;
10370 spin_lock_init(&tctx->task_lock);
10371 INIT_WQ_LIST(&tctx->task_list);
10372 INIT_WQ_LIST(&tctx->prio_task_list);
10373 init_task_work(&tctx->task_work, tctx_task_work);
10377 void __io_uring_free(struct task_struct *tsk)
10379 struct io_uring_task *tctx = tsk->io_uring;
10381 WARN_ON_ONCE(!xa_empty(&tctx->xa));
10382 WARN_ON_ONCE(tctx->io_wq);
10383 WARN_ON_ONCE(tctx->cached_refs);
10385 kfree(tctx->registered_rings);
10386 percpu_counter_destroy(&tctx->inflight);
10388 tsk->io_uring = NULL;
10391 static __cold int io_sq_offload_create(struct io_ring_ctx *ctx,
10392 struct io_uring_params *p)
10396 /* Retain compatibility with failing for an invalid attach attempt */
10397 if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
10398 IORING_SETUP_ATTACH_WQ) {
10401 f = fdget(p->wq_fd);
10404 if (f.file->f_op != &io_uring_fops) {
10410 if (ctx->flags & IORING_SETUP_SQPOLL) {
10411 struct task_struct *tsk;
10412 struct io_sq_data *sqd;
10415 ret = security_uring_sqpoll();
10419 sqd = io_get_sq_data(p, &attached);
10421 ret = PTR_ERR(sqd);
10425 ctx->sq_creds = get_current_cred();
10426 ctx->sq_data = sqd;
10427 ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
10428 if (!ctx->sq_thread_idle)
10429 ctx->sq_thread_idle = HZ;
10431 io_sq_thread_park(sqd);
10432 list_add(&ctx->sqd_list, &sqd->ctx_list);
10433 io_sqd_update_thread_idle(sqd);
10434 /* don't attach to a dying SQPOLL thread, would be racy */
10435 ret = (attached && !sqd->thread) ? -ENXIO : 0;
10436 io_sq_thread_unpark(sqd);
10443 if (p->flags & IORING_SETUP_SQ_AFF) {
10444 int cpu = p->sq_thread_cpu;
10447 if (cpu >= nr_cpu_ids || !cpu_online(cpu))
10454 sqd->task_pid = current->pid;
10455 sqd->task_tgid = current->tgid;
10456 tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
10458 ret = PTR_ERR(tsk);
10463 ret = io_uring_alloc_task_context(tsk, ctx);
10464 wake_up_new_task(tsk);
10467 } else if (p->flags & IORING_SETUP_SQ_AFF) {
10468 /* Can't have SQ_AFF without SQPOLL */
10475 complete(&ctx->sq_data->exited);
10477 io_sq_thread_finish(ctx);
10481 static inline void __io_unaccount_mem(struct user_struct *user,
10482 unsigned long nr_pages)
10484 atomic_long_sub(nr_pages, &user->locked_vm);
10487 static inline int __io_account_mem(struct user_struct *user,
10488 unsigned long nr_pages)
10490 unsigned long page_limit, cur_pages, new_pages;
10492 /* Don't allow more pages than we can safely lock */
10493 page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
10496 cur_pages = atomic_long_read(&user->locked_vm);
10497 new_pages = cur_pages + nr_pages;
10498 if (new_pages > page_limit)
10500 } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
10501 new_pages) != cur_pages);
10506 static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
10509 __io_unaccount_mem(ctx->user, nr_pages);
10511 if (ctx->mm_account)
10512 atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
10515 static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
10520 ret = __io_account_mem(ctx->user, nr_pages);
10525 if (ctx->mm_account)
10526 atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
10531 static void io_mem_free(void *ptr)
10538 page = virt_to_head_page(ptr);
10539 if (put_page_testzero(page))
10540 free_compound_page(page);
10543 static void *io_mem_alloc(size_t size)
10545 gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP;
10547 return (void *) __get_free_pages(gfp, get_order(size));
10550 static unsigned long rings_size(struct io_ring_ctx *ctx, unsigned int sq_entries,
10551 unsigned int cq_entries, size_t *sq_offset)
10553 struct io_rings *rings;
10554 size_t off, sq_array_size;
10556 off = struct_size(rings, cqes, cq_entries);
10557 if (off == SIZE_MAX)
10559 if (ctx->flags & IORING_SETUP_CQE32) {
10560 if (check_shl_overflow(off, 1, &off))
10565 off = ALIGN(off, SMP_CACHE_BYTES);
10573 sq_array_size = array_size(sizeof(u32), sq_entries);
10574 if (sq_array_size == SIZE_MAX)
10577 if (check_add_overflow(off, sq_array_size, &off))
10583 static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot)
10585 struct io_mapped_ubuf *imu = *slot;
10588 if (imu != ctx->dummy_ubuf) {
10589 for (i = 0; i < imu->nr_bvecs; i++)
10590 unpin_user_page(imu->bvec[i].bv_page);
10591 if (imu->acct_pages)
10592 io_unaccount_mem(ctx, imu->acct_pages);
10598 static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
10600 io_buffer_unmap(ctx, &prsrc->buf);
10604 static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
10608 for (i = 0; i < ctx->nr_user_bufs; i++)
10609 io_buffer_unmap(ctx, &ctx->user_bufs[i]);
10610 kfree(ctx->user_bufs);
10611 io_rsrc_data_free(ctx->buf_data);
10612 ctx->user_bufs = NULL;
10613 ctx->buf_data = NULL;
10614 ctx->nr_user_bufs = 0;
10617 static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
10619 unsigned nr = ctx->nr_user_bufs;
10622 if (!ctx->buf_data)
10626 * Quiesce may unlock ->uring_lock, and while it's not held
10627 * prevent new requests using the table.
10629 ctx->nr_user_bufs = 0;
10630 ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx);
10631 ctx->nr_user_bufs = nr;
10633 __io_sqe_buffers_unregister(ctx);
10637 static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
10638 void __user *arg, unsigned index)
10640 struct iovec __user *src;
10642 #ifdef CONFIG_COMPAT
10644 struct compat_iovec __user *ciovs;
10645 struct compat_iovec ciov;
10647 ciovs = (struct compat_iovec __user *) arg;
10648 if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
10651 dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
10652 dst->iov_len = ciov.iov_len;
10656 src = (struct iovec __user *) arg;
10657 if (copy_from_user(dst, &src[index], sizeof(*dst)))
10663 * Not super efficient, but this is just a registration time. And we do cache
10664 * the last compound head, so generally we'll only do a full search if we don't
10667 * We check if the given compound head page has already been accounted, to
10668 * avoid double accounting it. This allows us to account the full size of the
10669 * page, not just the constituent pages of a huge page.
10671 static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
10672 int nr_pages, struct page *hpage)
10676 /* check current page array */
10677 for (i = 0; i < nr_pages; i++) {
10678 if (!PageCompound(pages[i]))
10680 if (compound_head(pages[i]) == hpage)
10684 /* check previously registered pages */
10685 for (i = 0; i < ctx->nr_user_bufs; i++) {
10686 struct io_mapped_ubuf *imu = ctx->user_bufs[i];
10688 for (j = 0; j < imu->nr_bvecs; j++) {
10689 if (!PageCompound(imu->bvec[j].bv_page))
10691 if (compound_head(imu->bvec[j].bv_page) == hpage)
10699 static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
10700 int nr_pages, struct io_mapped_ubuf *imu,
10701 struct page **last_hpage)
10705 imu->acct_pages = 0;
10706 for (i = 0; i < nr_pages; i++) {
10707 if (!PageCompound(pages[i])) {
10710 struct page *hpage;
10712 hpage = compound_head(pages[i]);
10713 if (hpage == *last_hpage)
10715 *last_hpage = hpage;
10716 if (headpage_already_acct(ctx, pages, i, hpage))
10718 imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
10722 if (!imu->acct_pages)
10725 ret = io_account_mem(ctx, imu->acct_pages);
10727 imu->acct_pages = 0;
10731 static struct page **io_pin_pages(unsigned long ubuf, unsigned long len,
10734 unsigned long start, end, nr_pages;
10735 struct vm_area_struct **vmas = NULL;
10736 struct page **pages = NULL;
10737 int i, pret, ret = -ENOMEM;
10739 end = (ubuf + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
10740 start = ubuf >> PAGE_SHIFT;
10741 nr_pages = end - start;
10743 pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
10747 vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
10753 mmap_read_lock(current->mm);
10754 pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
10756 if (pret == nr_pages) {
10757 /* don't support file backed memory */
10758 for (i = 0; i < nr_pages; i++) {
10759 struct vm_area_struct *vma = vmas[i];
10761 if (vma_is_shmem(vma))
10763 if (vma->vm_file &&
10764 !is_file_hugepages(vma->vm_file)) {
10769 *npages = nr_pages;
10771 ret = pret < 0 ? pret : -EFAULT;
10773 mmap_read_unlock(current->mm);
10776 * if we did partial map, or found file backed vmas,
10777 * release any pages we did get
10780 unpin_user_pages(pages, pret);
10788 pages = ERR_PTR(ret);
10793 static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
10794 struct io_mapped_ubuf **pimu,
10795 struct page **last_hpage)
10797 struct io_mapped_ubuf *imu = NULL;
10798 struct page **pages = NULL;
10801 int ret, nr_pages, i;
10803 if (!iov->iov_base) {
10804 *pimu = ctx->dummy_ubuf;
10811 pages = io_pin_pages((unsigned long) iov->iov_base, iov->iov_len,
10813 if (IS_ERR(pages)) {
10814 ret = PTR_ERR(pages);
10819 imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL);
10823 ret = io_buffer_account_pin(ctx, pages, nr_pages, imu, last_hpage);
10825 unpin_user_pages(pages, nr_pages);
10829 off = (unsigned long) iov->iov_base & ~PAGE_MASK;
10830 size = iov->iov_len;
10831 for (i = 0; i < nr_pages; i++) {
10834 vec_len = min_t(size_t, size, PAGE_SIZE - off);
10835 imu->bvec[i].bv_page = pages[i];
10836 imu->bvec[i].bv_len = vec_len;
10837 imu->bvec[i].bv_offset = off;
10841 /* store original address for later verification */
10842 imu->ubuf = (unsigned long) iov->iov_base;
10843 imu->ubuf_end = imu->ubuf + iov->iov_len;
10844 imu->nr_bvecs = nr_pages;
10854 static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
10856 ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL);
10857 return ctx->user_bufs ? 0 : -ENOMEM;
10860 static int io_buffer_validate(struct iovec *iov)
10862 unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1);
10865 * Don't impose further limits on the size and buffer
10866 * constraints here, we'll -EINVAL later when IO is
10867 * submitted if they are wrong.
10869 if (!iov->iov_base)
10870 return iov->iov_len ? -EFAULT : 0;
10874 /* arbitrary limit, but we need something */
10875 if (iov->iov_len > SZ_1G)
10878 if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp))
10884 static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
10885 unsigned int nr_args, u64 __user *tags)
10887 struct page *last_hpage = NULL;
10888 struct io_rsrc_data *data;
10892 if (ctx->user_bufs)
10894 if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS)
10896 ret = io_rsrc_node_switch_start(ctx);
10899 ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data);
10902 ret = io_buffers_map_alloc(ctx, nr_args);
10904 io_rsrc_data_free(data);
10908 for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) {
10910 ret = io_copy_iov(ctx, &iov, arg, i);
10913 ret = io_buffer_validate(&iov);
10917 memset(&iov, 0, sizeof(iov));
10920 if (!iov.iov_base && *io_get_tag_slot(data, i)) {
10925 ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i],
10931 WARN_ON_ONCE(ctx->buf_data);
10933 ctx->buf_data = data;
10935 __io_sqe_buffers_unregister(ctx);
10937 io_rsrc_node_switch(ctx, NULL);
10941 static int __io_sqe_buffers_update(struct io_ring_ctx *ctx,
10942 struct io_uring_rsrc_update2 *up,
10943 unsigned int nr_args)
10945 u64 __user *tags = u64_to_user_ptr(up->tags);
10946 struct iovec iov, __user *iovs = u64_to_user_ptr(up->data);
10947 struct page *last_hpage = NULL;
10948 bool needs_switch = false;
10952 if (!ctx->buf_data)
10954 if (up->offset + nr_args > ctx->nr_user_bufs)
10957 for (done = 0; done < nr_args; done++) {
10958 struct io_mapped_ubuf *imu;
10959 int offset = up->offset + done;
10962 err = io_copy_iov(ctx, &iov, iovs, done);
10965 if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) {
10969 err = io_buffer_validate(&iov);
10972 if (!iov.iov_base && tag) {
10976 err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage);
10980 i = array_index_nospec(offset, ctx->nr_user_bufs);
10981 if (ctx->user_bufs[i] != ctx->dummy_ubuf) {
10982 err = io_queue_rsrc_removal(ctx->buf_data, i,
10983 ctx->rsrc_node, ctx->user_bufs[i]);
10984 if (unlikely(err)) {
10985 io_buffer_unmap(ctx, &imu);
10988 ctx->user_bufs[i] = NULL;
10989 needs_switch = true;
10992 ctx->user_bufs[i] = imu;
10993 *io_get_tag_slot(ctx->buf_data, offset) = tag;
10997 io_rsrc_node_switch(ctx, ctx->buf_data);
10998 return done ? done : err;
11001 static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg,
11002 unsigned int eventfd_async)
11004 struct io_ev_fd *ev_fd;
11005 __s32 __user *fds = arg;
11008 ev_fd = rcu_dereference_protected(ctx->io_ev_fd,
11009 lockdep_is_held(&ctx->uring_lock));
11013 if (copy_from_user(&fd, fds, sizeof(*fds)))
11016 ev_fd = kmalloc(sizeof(*ev_fd), GFP_KERNEL);
11020 ev_fd->cq_ev_fd = eventfd_ctx_fdget(fd);
11021 if (IS_ERR(ev_fd->cq_ev_fd)) {
11022 int ret = PTR_ERR(ev_fd->cq_ev_fd);
11026 ev_fd->eventfd_async = eventfd_async;
11027 ctx->has_evfd = true;
11028 rcu_assign_pointer(ctx->io_ev_fd, ev_fd);
11032 static void io_eventfd_put(struct rcu_head *rcu)
11034 struct io_ev_fd *ev_fd = container_of(rcu, struct io_ev_fd, rcu);
11036 eventfd_ctx_put(ev_fd->cq_ev_fd);
11040 static int io_eventfd_unregister(struct io_ring_ctx *ctx)
11042 struct io_ev_fd *ev_fd;
11044 ev_fd = rcu_dereference_protected(ctx->io_ev_fd,
11045 lockdep_is_held(&ctx->uring_lock));
11047 ctx->has_evfd = false;
11048 rcu_assign_pointer(ctx->io_ev_fd, NULL);
11049 call_rcu(&ev_fd->rcu, io_eventfd_put);
11056 static void io_destroy_buffers(struct io_ring_ctx *ctx)
11058 struct io_buffer_list *bl;
11059 unsigned long index;
11062 for (i = 0; i < BGID_ARRAY; i++) {
11065 __io_remove_buffers(ctx, &ctx->io_bl[i], -1U);
11068 xa_for_each(&ctx->io_bl_xa, index, bl) {
11069 xa_erase(&ctx->io_bl_xa, bl->bgid);
11070 __io_remove_buffers(ctx, bl, -1U);
11074 while (!list_empty(&ctx->io_buffers_pages)) {
11077 page = list_first_entry(&ctx->io_buffers_pages, struct page, lru);
11078 list_del_init(&page->lru);
11083 static void io_req_caches_free(struct io_ring_ctx *ctx)
11085 struct io_submit_state *state = &ctx->submit_state;
11088 mutex_lock(&ctx->uring_lock);
11089 io_flush_cached_locked_reqs(ctx, state);
11091 while (!io_req_cache_empty(ctx)) {
11092 struct io_wq_work_node *node;
11093 struct io_kiocb *req;
11095 node = wq_stack_extract(&state->free_list);
11096 req = container_of(node, struct io_kiocb, comp_list);
11097 kmem_cache_free(req_cachep, req);
11101 percpu_ref_put_many(&ctx->refs, nr);
11102 mutex_unlock(&ctx->uring_lock);
11105 static void io_wait_rsrc_data(struct io_rsrc_data *data)
11107 if (data && !atomic_dec_and_test(&data->refs))
11108 wait_for_completion(&data->done);
11111 static void io_flush_apoll_cache(struct io_ring_ctx *ctx)
11113 struct async_poll *apoll;
11115 while (!list_empty(&ctx->apoll_cache)) {
11116 apoll = list_first_entry(&ctx->apoll_cache, struct async_poll,
11118 list_del(&apoll->poll.wait.entry);
11123 static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx)
11125 io_sq_thread_finish(ctx);
11127 if (ctx->mm_account) {
11128 mmdrop(ctx->mm_account);
11129 ctx->mm_account = NULL;
11132 io_rsrc_refs_drop(ctx);
11133 /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */
11134 io_wait_rsrc_data(ctx->buf_data);
11135 io_wait_rsrc_data(ctx->file_data);
11137 mutex_lock(&ctx->uring_lock);
11139 __io_sqe_buffers_unregister(ctx);
11140 if (ctx->file_data)
11141 __io_sqe_files_unregister(ctx);
11143 __io_cqring_overflow_flush(ctx, true);
11144 io_eventfd_unregister(ctx);
11145 io_flush_apoll_cache(ctx);
11146 mutex_unlock(&ctx->uring_lock);
11147 io_destroy_buffers(ctx);
11149 put_cred(ctx->sq_creds);
11151 /* there are no registered resources left, nobody uses it */
11152 if (ctx->rsrc_node)
11153 io_rsrc_node_destroy(ctx->rsrc_node);
11154 if (ctx->rsrc_backup_node)
11155 io_rsrc_node_destroy(ctx->rsrc_backup_node);
11156 flush_delayed_work(&ctx->rsrc_put_work);
11157 flush_delayed_work(&ctx->fallback_work);
11159 WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list));
11160 WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist));
11162 #if defined(CONFIG_UNIX)
11163 if (ctx->ring_sock) {
11164 ctx->ring_sock->file = NULL; /* so that iput() is called */
11165 sock_release(ctx->ring_sock);
11168 WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list));
11170 io_mem_free(ctx->rings);
11171 io_mem_free(ctx->sq_sqes);
11173 percpu_ref_exit(&ctx->refs);
11174 free_uid(ctx->user);
11175 io_req_caches_free(ctx);
11177 io_wq_put_hash(ctx->hash_map);
11178 kfree(ctx->cancel_hash);
11179 kfree(ctx->dummy_ubuf);
11181 xa_destroy(&ctx->io_bl_xa);
11185 static __poll_t io_uring_poll(struct file *file, poll_table *wait)
11187 struct io_ring_ctx *ctx = file->private_data;
11190 poll_wait(file, &ctx->cq_wait, wait);
11192 * synchronizes with barrier from wq_has_sleeper call in
11196 if (!io_sqring_full(ctx))
11197 mask |= EPOLLOUT | EPOLLWRNORM;
11200 * Don't flush cqring overflow list here, just do a simple check.
11201 * Otherwise there could possible be ABBA deadlock:
11204 * lock(&ctx->uring_lock);
11206 * lock(&ctx->uring_lock);
11209 * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
11210 * pushs them to do the flush.
11212 if (io_cqring_events(ctx) ||
11213 test_bit(IO_CHECK_CQ_OVERFLOW_BIT, &ctx->check_cq))
11214 mask |= EPOLLIN | EPOLLRDNORM;
11219 static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
11221 const struct cred *creds;
11223 creds = xa_erase(&ctx->personalities, id);
11232 struct io_tctx_exit {
11233 struct callback_head task_work;
11234 struct completion completion;
11235 struct io_ring_ctx *ctx;
11238 static __cold void io_tctx_exit_cb(struct callback_head *cb)
11240 struct io_uring_task *tctx = current->io_uring;
11241 struct io_tctx_exit *work;
11243 work = container_of(cb, struct io_tctx_exit, task_work);
11245 * When @in_idle, we're in cancellation and it's racy to remove the
11246 * node. It'll be removed by the end of cancellation, just ignore it.
11248 if (!atomic_read(&tctx->in_idle))
11249 io_uring_del_tctx_node((unsigned long)work->ctx);
11250 complete(&work->completion);
11253 static __cold bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
11255 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
11257 return req->ctx == data;
11260 static __cold void io_ring_exit_work(struct work_struct *work)
11262 struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
11263 unsigned long timeout = jiffies + HZ * 60 * 5;
11264 unsigned long interval = HZ / 20;
11265 struct io_tctx_exit exit;
11266 struct io_tctx_node *node;
11270 * If we're doing polled IO and end up having requests being
11271 * submitted async (out-of-line), then completions can come in while
11272 * we're waiting for refs to drop. We need to reap these manually,
11273 * as nobody else will be looking for them.
11276 io_uring_try_cancel_requests(ctx, NULL, true);
11277 if (ctx->sq_data) {
11278 struct io_sq_data *sqd = ctx->sq_data;
11279 struct task_struct *tsk;
11281 io_sq_thread_park(sqd);
11283 if (tsk && tsk->io_uring && tsk->io_uring->io_wq)
11284 io_wq_cancel_cb(tsk->io_uring->io_wq,
11285 io_cancel_ctx_cb, ctx, true);
11286 io_sq_thread_unpark(sqd);
11289 io_req_caches_free(ctx);
11291 if (WARN_ON_ONCE(time_after(jiffies, timeout))) {
11292 /* there is little hope left, don't run it too often */
11293 interval = HZ * 60;
11295 } while (!wait_for_completion_timeout(&ctx->ref_comp, interval));
11297 init_completion(&exit.completion);
11298 init_task_work(&exit.task_work, io_tctx_exit_cb);
11301 * Some may use context even when all refs and requests have been put,
11302 * and they are free to do so while still holding uring_lock or
11303 * completion_lock, see io_req_task_submit(). Apart from other work,
11304 * this lock/unlock section also waits them to finish.
11306 mutex_lock(&ctx->uring_lock);
11307 while (!list_empty(&ctx->tctx_list)) {
11308 WARN_ON_ONCE(time_after(jiffies, timeout));
11310 node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
11312 /* don't spin on a single task if cancellation failed */
11313 list_rotate_left(&ctx->tctx_list);
11314 ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
11315 if (WARN_ON_ONCE(ret))
11318 mutex_unlock(&ctx->uring_lock);
11319 wait_for_completion(&exit.completion);
11320 mutex_lock(&ctx->uring_lock);
11322 mutex_unlock(&ctx->uring_lock);
11323 spin_lock(&ctx->completion_lock);
11324 spin_unlock(&ctx->completion_lock);
11326 io_ring_ctx_free(ctx);
11329 /* Returns true if we found and killed one or more timeouts */
11330 static __cold bool io_kill_timeouts(struct io_ring_ctx *ctx,
11331 struct task_struct *tsk, bool cancel_all)
11333 struct io_kiocb *req, *tmp;
11336 spin_lock(&ctx->completion_lock);
11337 spin_lock_irq(&ctx->timeout_lock);
11338 list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
11339 if (io_match_task(req, tsk, cancel_all)) {
11340 io_kill_timeout(req, -ECANCELED);
11344 spin_unlock_irq(&ctx->timeout_lock);
11345 io_commit_cqring(ctx);
11346 spin_unlock(&ctx->completion_lock);
11348 io_cqring_ev_posted(ctx);
11349 return canceled != 0;
11352 static __cold void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
11354 unsigned long index;
11355 struct creds *creds;
11357 mutex_lock(&ctx->uring_lock);
11358 percpu_ref_kill(&ctx->refs);
11360 __io_cqring_overflow_flush(ctx, true);
11361 xa_for_each(&ctx->personalities, index, creds)
11362 io_unregister_personality(ctx, index);
11363 mutex_unlock(&ctx->uring_lock);
11365 /* failed during ring init, it couldn't have issued any requests */
11367 io_kill_timeouts(ctx, NULL, true);
11368 io_poll_remove_all(ctx, NULL, true);
11369 /* if we failed setting up the ctx, we might not have any rings */
11370 io_iopoll_try_reap_events(ctx);
11373 INIT_WORK(&ctx->exit_work, io_ring_exit_work);
11375 * Use system_unbound_wq to avoid spawning tons of event kworkers
11376 * if we're exiting a ton of rings at the same time. It just adds
11377 * noise and overhead, there's no discernable change in runtime
11378 * over using system_wq.
11380 queue_work(system_unbound_wq, &ctx->exit_work);
11383 static int io_uring_release(struct inode *inode, struct file *file)
11385 struct io_ring_ctx *ctx = file->private_data;
11387 file->private_data = NULL;
11388 io_ring_ctx_wait_and_kill(ctx);
11392 struct io_task_cancel {
11393 struct task_struct *task;
11397 static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
11399 struct io_kiocb *req = container_of(work, struct io_kiocb, work);
11400 struct io_task_cancel *cancel = data;
11402 return io_match_task_safe(req, cancel->task, cancel->all);
11405 static __cold bool io_cancel_defer_files(struct io_ring_ctx *ctx,
11406 struct task_struct *task,
11409 struct io_defer_entry *de;
11412 spin_lock(&ctx->completion_lock);
11413 list_for_each_entry_reverse(de, &ctx->defer_list, list) {
11414 if (io_match_task_safe(de->req, task, cancel_all)) {
11415 list_cut_position(&list, &ctx->defer_list, &de->list);
11419 spin_unlock(&ctx->completion_lock);
11420 if (list_empty(&list))
11423 while (!list_empty(&list)) {
11424 de = list_first_entry(&list, struct io_defer_entry, list);
11425 list_del_init(&de->list);
11426 io_req_complete_failed(de->req, -ECANCELED);
11432 static __cold bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
11434 struct io_tctx_node *node;
11435 enum io_wq_cancel cret;
11438 mutex_lock(&ctx->uring_lock);
11439 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
11440 struct io_uring_task *tctx = node->task->io_uring;
11443 * io_wq will stay alive while we hold uring_lock, because it's
11444 * killed after ctx nodes, which requires to take the lock.
11446 if (!tctx || !tctx->io_wq)
11448 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
11449 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
11451 mutex_unlock(&ctx->uring_lock);
11456 static __cold void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
11457 struct task_struct *task,
11460 struct io_task_cancel cancel = { .task = task, .all = cancel_all, };
11461 struct io_uring_task *tctx = task ? task->io_uring : NULL;
11463 /* failed during ring init, it couldn't have issued any requests */
11468 enum io_wq_cancel cret;
11472 ret |= io_uring_try_cancel_iowq(ctx);
11473 } else if (tctx && tctx->io_wq) {
11475 * Cancels requests of all rings, not only @ctx, but
11476 * it's fine as the task is in exit/exec.
11478 cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
11480 ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
11483 /* SQPOLL thread does its own polling */
11484 if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) ||
11485 (ctx->sq_data && ctx->sq_data->thread == current)) {
11486 while (!wq_list_empty(&ctx->iopoll_list)) {
11487 io_iopoll_try_reap_events(ctx);
11492 ret |= io_cancel_defer_files(ctx, task, cancel_all);
11493 ret |= io_poll_remove_all(ctx, task, cancel_all);
11494 ret |= io_kill_timeouts(ctx, task, cancel_all);
11496 ret |= io_run_task_work();
11503 static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
11505 struct io_uring_task *tctx = current->io_uring;
11506 struct io_tctx_node *node;
11509 if (unlikely(!tctx)) {
11510 ret = io_uring_alloc_task_context(current, ctx);
11514 tctx = current->io_uring;
11515 if (ctx->iowq_limits_set) {
11516 unsigned int limits[2] = { ctx->iowq_limits[0],
11517 ctx->iowq_limits[1], };
11519 ret = io_wq_max_workers(tctx->io_wq, limits);
11524 if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
11525 node = kmalloc(sizeof(*node), GFP_KERNEL);
11529 node->task = current;
11531 ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
11532 node, GFP_KERNEL));
11538 mutex_lock(&ctx->uring_lock);
11539 list_add(&node->ctx_node, &ctx->tctx_list);
11540 mutex_unlock(&ctx->uring_lock);
11547 * Note that this task has used io_uring. We use it for cancelation purposes.
11549 static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
11551 struct io_uring_task *tctx = current->io_uring;
11553 if (likely(tctx && tctx->last == ctx))
11555 return __io_uring_add_tctx_node(ctx);
11559 * Remove this io_uring_file -> task mapping.
11561 static __cold void io_uring_del_tctx_node(unsigned long index)
11563 struct io_uring_task *tctx = current->io_uring;
11564 struct io_tctx_node *node;
11568 node = xa_erase(&tctx->xa, index);
11572 WARN_ON_ONCE(current != node->task);
11573 WARN_ON_ONCE(list_empty(&node->ctx_node));
11575 mutex_lock(&node->ctx->uring_lock);
11576 list_del(&node->ctx_node);
11577 mutex_unlock(&node->ctx->uring_lock);
11579 if (tctx->last == node->ctx)
11584 static __cold void io_uring_clean_tctx(struct io_uring_task *tctx)
11586 struct io_wq *wq = tctx->io_wq;
11587 struct io_tctx_node *node;
11588 unsigned long index;
11590 xa_for_each(&tctx->xa, index, node) {
11591 io_uring_del_tctx_node(index);
11596 * Must be after io_uring_del_tctx_node() (removes nodes under
11597 * uring_lock) to avoid race with io_uring_try_cancel_iowq().
11599 io_wq_put_and_exit(wq);
11600 tctx->io_wq = NULL;
11604 static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
11607 return atomic_read(&tctx->inflight_tracked);
11608 return percpu_counter_sum(&tctx->inflight);
11612 * Find any io_uring ctx that this task has registered or done IO on, and cancel
11613 * requests. @sqd should be not-null IFF it's an SQPOLL thread cancellation.
11615 static __cold void io_uring_cancel_generic(bool cancel_all,
11616 struct io_sq_data *sqd)
11618 struct io_uring_task *tctx = current->io_uring;
11619 struct io_ring_ctx *ctx;
11623 WARN_ON_ONCE(sqd && sqd->thread != current);
11625 if (!current->io_uring)
11628 io_wq_exit_start(tctx->io_wq);
11630 atomic_inc(&tctx->in_idle);
11632 io_uring_drop_tctx_refs(current);
11633 /* read completions before cancelations */
11634 inflight = tctx_inflight(tctx, !cancel_all);
11639 struct io_tctx_node *node;
11640 unsigned long index;
11642 xa_for_each(&tctx->xa, index, node) {
11643 /* sqpoll task will cancel all its requests */
11644 if (node->ctx->sq_data)
11646 io_uring_try_cancel_requests(node->ctx, current,
11650 list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
11651 io_uring_try_cancel_requests(ctx, current,
11655 prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE);
11656 io_run_task_work();
11657 io_uring_drop_tctx_refs(current);
11660 * If we've seen completions, retry without waiting. This
11661 * avoids a race where a completion comes in before we did
11662 * prepare_to_wait().
11664 if (inflight == tctx_inflight(tctx, !cancel_all))
11666 finish_wait(&tctx->wait, &wait);
11669 io_uring_clean_tctx(tctx);
11672 * We shouldn't run task_works after cancel, so just leave
11673 * ->in_idle set for normal exit.
11675 atomic_dec(&tctx->in_idle);
11676 /* for exec all current's requests should be gone, kill tctx */
11677 __io_uring_free(current);
11681 void __io_uring_cancel(bool cancel_all)
11683 io_uring_cancel_generic(cancel_all, NULL);
11686 void io_uring_unreg_ringfd(void)
11688 struct io_uring_task *tctx = current->io_uring;
11691 for (i = 0; i < IO_RINGFD_REG_MAX; i++) {
11692 if (tctx->registered_rings[i]) {
11693 fput(tctx->registered_rings[i]);
11694 tctx->registered_rings[i] = NULL;
11699 static int io_ring_add_registered_fd(struct io_uring_task *tctx, int fd,
11700 int start, int end)
11705 for (offset = start; offset < end; offset++) {
11706 offset = array_index_nospec(offset, IO_RINGFD_REG_MAX);
11707 if (tctx->registered_rings[offset])
11713 } else if (file->f_op != &io_uring_fops) {
11715 return -EOPNOTSUPP;
11717 tctx->registered_rings[offset] = file;
11725 * Register a ring fd to avoid fdget/fdput for each io_uring_enter()
11726 * invocation. User passes in an array of struct io_uring_rsrc_update
11727 * with ->data set to the ring_fd, and ->offset given for the desired
11728 * index. If no index is desired, application may set ->offset == -1U
11729 * and we'll find an available index. Returns number of entries
11730 * successfully processed, or < 0 on error if none were processed.
11732 static int io_ringfd_register(struct io_ring_ctx *ctx, void __user *__arg,
11735 struct io_uring_rsrc_update __user *arg = __arg;
11736 struct io_uring_rsrc_update reg;
11737 struct io_uring_task *tctx;
11740 if (!nr_args || nr_args > IO_RINGFD_REG_MAX)
11743 mutex_unlock(&ctx->uring_lock);
11744 ret = io_uring_add_tctx_node(ctx);
11745 mutex_lock(&ctx->uring_lock);
11749 tctx = current->io_uring;
11750 for (i = 0; i < nr_args; i++) {
11753 if (copy_from_user(®, &arg[i], sizeof(reg))) {
11763 if (reg.offset == -1U) {
11765 end = IO_RINGFD_REG_MAX;
11767 if (reg.offset >= IO_RINGFD_REG_MAX) {
11771 start = reg.offset;
11775 ret = io_ring_add_registered_fd(tctx, reg.data, start, end);
11780 if (copy_to_user(&arg[i], ®, sizeof(reg))) {
11781 fput(tctx->registered_rings[reg.offset]);
11782 tctx->registered_rings[reg.offset] = NULL;
11788 return i ? i : ret;
11791 static int io_ringfd_unregister(struct io_ring_ctx *ctx, void __user *__arg,
11794 struct io_uring_rsrc_update __user *arg = __arg;
11795 struct io_uring_task *tctx = current->io_uring;
11796 struct io_uring_rsrc_update reg;
11799 if (!nr_args || nr_args > IO_RINGFD_REG_MAX)
11804 for (i = 0; i < nr_args; i++) {
11805 if (copy_from_user(®, &arg[i], sizeof(reg))) {
11809 if (reg.resv || reg.data || reg.offset >= IO_RINGFD_REG_MAX) {
11814 reg.offset = array_index_nospec(reg.offset, IO_RINGFD_REG_MAX);
11815 if (tctx->registered_rings[reg.offset]) {
11816 fput(tctx->registered_rings[reg.offset]);
11817 tctx->registered_rings[reg.offset] = NULL;
11821 return i ? i : ret;
11824 static void *io_uring_validate_mmap_request(struct file *file,
11825 loff_t pgoff, size_t sz)
11827 struct io_ring_ctx *ctx = file->private_data;
11828 loff_t offset = pgoff << PAGE_SHIFT;
11833 case IORING_OFF_SQ_RING:
11834 case IORING_OFF_CQ_RING:
11837 case IORING_OFF_SQES:
11838 ptr = ctx->sq_sqes;
11841 return ERR_PTR(-EINVAL);
11844 page = virt_to_head_page(ptr);
11845 if (sz > page_size(page))
11846 return ERR_PTR(-EINVAL);
11853 static __cold int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
11855 size_t sz = vma->vm_end - vma->vm_start;
11859 ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
11861 return PTR_ERR(ptr);
11863 pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
11864 return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
11867 #else /* !CONFIG_MMU */
11869 static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
11871 return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
11874 static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
11876 return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
11879 static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
11880 unsigned long addr, unsigned long len,
11881 unsigned long pgoff, unsigned long flags)
11885 ptr = io_uring_validate_mmap_request(file, pgoff, len);
11887 return PTR_ERR(ptr);
11889 return (unsigned long) ptr;
11892 #endif /* !CONFIG_MMU */
11894 static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
11899 if (!io_sqring_full(ctx))
11901 prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
11903 if (!io_sqring_full(ctx))
11906 } while (!signal_pending(current));
11908 finish_wait(&ctx->sqo_sq_wait, &wait);
11912 static int io_validate_ext_arg(unsigned flags, const void __user *argp, size_t argsz)
11914 if (flags & IORING_ENTER_EXT_ARG) {
11915 struct io_uring_getevents_arg arg;
11917 if (argsz != sizeof(arg))
11919 if (copy_from_user(&arg, argp, sizeof(arg)))
11925 static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
11926 struct __kernel_timespec __user **ts,
11927 const sigset_t __user **sig)
11929 struct io_uring_getevents_arg arg;
11932 * If EXT_ARG isn't set, then we have no timespec and the argp pointer
11933 * is just a pointer to the sigset_t.
11935 if (!(flags & IORING_ENTER_EXT_ARG)) {
11936 *sig = (const sigset_t __user *) argp;
11942 * EXT_ARG is set - ensure we agree on the size of it and copy in our
11943 * timespec and sigset_t pointers if good.
11945 if (*argsz != sizeof(arg))
11947 if (copy_from_user(&arg, argp, sizeof(arg)))
11951 *sig = u64_to_user_ptr(arg.sigmask);
11952 *argsz = arg.sigmask_sz;
11953 *ts = u64_to_user_ptr(arg.ts);
11957 SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
11958 u32, min_complete, u32, flags, const void __user *, argp,
11961 struct io_ring_ctx *ctx;
11965 io_run_task_work();
11967 if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
11968 IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG |
11969 IORING_ENTER_REGISTERED_RING)))
11973 * Ring fd has been registered via IORING_REGISTER_RING_FDS, we
11974 * need only dereference our task private array to find it.
11976 if (flags & IORING_ENTER_REGISTERED_RING) {
11977 struct io_uring_task *tctx = current->io_uring;
11979 if (!tctx || fd >= IO_RINGFD_REG_MAX)
11981 fd = array_index_nospec(fd, IO_RINGFD_REG_MAX);
11982 f.file = tctx->registered_rings[fd];
11988 if (unlikely(!f.file))
11992 if (unlikely(f.file->f_op != &io_uring_fops))
11996 ctx = f.file->private_data;
11997 if (unlikely(!percpu_ref_tryget(&ctx->refs)))
12001 if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED))
12005 * For SQ polling, the thread will do all submissions and completions.
12006 * Just return the requested submit count, and wake the thread if
12007 * we were asked to.
12010 if (ctx->flags & IORING_SETUP_SQPOLL) {
12011 io_cqring_overflow_flush(ctx);
12013 if (unlikely(ctx->sq_data->thread == NULL)) {
12017 if (flags & IORING_ENTER_SQ_WAKEUP)
12018 wake_up(&ctx->sq_data->wait);
12019 if (flags & IORING_ENTER_SQ_WAIT) {
12020 ret = io_sqpoll_wait_sq(ctx);
12025 } else if (to_submit) {
12026 ret = io_uring_add_tctx_node(ctx);
12030 mutex_lock(&ctx->uring_lock);
12031 ret = io_submit_sqes(ctx, to_submit);
12032 if (ret != to_submit) {
12033 mutex_unlock(&ctx->uring_lock);
12036 if ((flags & IORING_ENTER_GETEVENTS) && ctx->syscall_iopoll)
12037 goto iopoll_locked;
12038 mutex_unlock(&ctx->uring_lock);
12040 if (flags & IORING_ENTER_GETEVENTS) {
12042 if (ctx->syscall_iopoll) {
12044 * We disallow the app entering submit/complete with
12045 * polling, but we still need to lock the ring to
12046 * prevent racing with polled issue that got punted to
12049 mutex_lock(&ctx->uring_lock);
12051 ret2 = io_validate_ext_arg(flags, argp, argsz);
12052 if (likely(!ret2)) {
12053 min_complete = min(min_complete,
12055 ret2 = io_iopoll_check(ctx, min_complete);
12057 mutex_unlock(&ctx->uring_lock);
12059 const sigset_t __user *sig;
12060 struct __kernel_timespec __user *ts;
12062 ret2 = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
12063 if (likely(!ret2)) {
12064 min_complete = min(min_complete,
12066 ret2 = io_cqring_wait(ctx, min_complete, sig,
12075 * EBADR indicates that one or more CQE were dropped.
12076 * Once the user has been informed we can clear the bit
12077 * as they are obviously ok with those drops.
12079 if (unlikely(ret2 == -EBADR))
12080 clear_bit(IO_CHECK_CQ_DROPPED_BIT,
12086 percpu_ref_put(&ctx->refs);
12092 #ifdef CONFIG_PROC_FS
12093 static __cold int io_uring_show_cred(struct seq_file *m, unsigned int id,
12094 const struct cred *cred)
12096 struct user_namespace *uns = seq_user_ns(m);
12097 struct group_info *gi;
12102 seq_printf(m, "%5d\n", id);
12103 seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
12104 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
12105 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
12106 seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
12107 seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
12108 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
12109 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
12110 seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
12111 seq_puts(m, "\n\tGroups:\t");
12112 gi = cred->group_info;
12113 for (g = 0; g < gi->ngroups; g++) {
12114 seq_put_decimal_ull(m, g ? " " : "",
12115 from_kgid_munged(uns, gi->gid[g]));
12117 seq_puts(m, "\n\tCapEff:\t");
12118 cap = cred->cap_effective;
12119 CAP_FOR_EACH_U32(__capi)
12120 seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
12125 static __cold void __io_uring_show_fdinfo(struct io_ring_ctx *ctx,
12126 struct seq_file *m)
12128 struct io_sq_data *sq = NULL;
12129 struct io_overflow_cqe *ocqe;
12130 struct io_rings *r = ctx->rings;
12131 unsigned int sq_mask = ctx->sq_entries - 1, cq_mask = ctx->cq_entries - 1;
12132 unsigned int sq_head = READ_ONCE(r->sq.head);
12133 unsigned int sq_tail = READ_ONCE(r->sq.tail);
12134 unsigned int cq_head = READ_ONCE(r->cq.head);
12135 unsigned int cq_tail = READ_ONCE(r->cq.tail);
12136 unsigned int cq_shift = 0;
12137 unsigned int sq_entries, cq_entries;
12139 bool is_cqe32 = (ctx->flags & IORING_SETUP_CQE32);
12146 * we may get imprecise sqe and cqe info if uring is actively running
12147 * since we get cached_sq_head and cached_cq_tail without uring_lock
12148 * and sq_tail and cq_head are changed by userspace. But it's ok since
12149 * we usually use these info when it is stuck.
12151 seq_printf(m, "SqMask:\t0x%x\n", sq_mask);
12152 seq_printf(m, "SqHead:\t%u\n", sq_head);
12153 seq_printf(m, "SqTail:\t%u\n", sq_tail);
12154 seq_printf(m, "CachedSqHead:\t%u\n", ctx->cached_sq_head);
12155 seq_printf(m, "CqMask:\t0x%x\n", cq_mask);
12156 seq_printf(m, "CqHead:\t%u\n", cq_head);
12157 seq_printf(m, "CqTail:\t%u\n", cq_tail);
12158 seq_printf(m, "CachedCqTail:\t%u\n", ctx->cached_cq_tail);
12159 seq_printf(m, "SQEs:\t%u\n", sq_tail - ctx->cached_sq_head);
12160 sq_entries = min(sq_tail - sq_head, ctx->sq_entries);
12161 for (i = 0; i < sq_entries; i++) {
12162 unsigned int entry = i + sq_head;
12163 unsigned int sq_idx = READ_ONCE(ctx->sq_array[entry & sq_mask]);
12164 struct io_uring_sqe *sqe;
12166 if (sq_idx > sq_mask)
12168 sqe = &ctx->sq_sqes[sq_idx];
12169 seq_printf(m, "%5u: opcode:%d, fd:%d, flags:%x, user_data:%llu\n",
12170 sq_idx, sqe->opcode, sqe->fd, sqe->flags,
12173 seq_printf(m, "CQEs:\t%u\n", cq_tail - cq_head);
12174 cq_entries = min(cq_tail - cq_head, ctx->cq_entries);
12175 for (i = 0; i < cq_entries; i++) {
12176 unsigned int entry = i + cq_head;
12177 struct io_uring_cqe *cqe = &r->cqes[(entry & cq_mask) << cq_shift];
12180 seq_printf(m, "%5u: user_data:%llu, res:%d, flag:%x\n",
12181 entry & cq_mask, cqe->user_data, cqe->res,
12184 seq_printf(m, "%5u: user_data:%llu, res:%d, flag:%x, "
12185 "extra1:%llu, extra2:%llu\n",
12186 entry & cq_mask, cqe->user_data, cqe->res,
12187 cqe->flags, cqe->big_cqe[0], cqe->big_cqe[1]);
12192 * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
12193 * since fdinfo case grabs it in the opposite direction of normal use
12194 * cases. If we fail to get the lock, we just don't iterate any
12195 * structures that could be going away outside the io_uring mutex.
12197 has_lock = mutex_trylock(&ctx->uring_lock);
12199 if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
12205 seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
12206 seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
12207 seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
12208 for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
12209 struct file *f = io_file_from_index(ctx, i);
12212 seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
12214 seq_printf(m, "%5u: <none>\n", i);
12216 seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
12217 for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
12218 struct io_mapped_ubuf *buf = ctx->user_bufs[i];
12219 unsigned int len = buf->ubuf_end - buf->ubuf;
12221 seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
12223 if (has_lock && !xa_empty(&ctx->personalities)) {
12224 unsigned long index;
12225 const struct cred *cred;
12227 seq_printf(m, "Personalities:\n");
12228 xa_for_each(&ctx->personalities, index, cred)
12229 io_uring_show_cred(m, index, cred);
12232 mutex_unlock(&ctx->uring_lock);
12234 seq_puts(m, "PollList:\n");
12235 spin_lock(&ctx->completion_lock);
12236 for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
12237 struct hlist_head *list = &ctx->cancel_hash[i];
12238 struct io_kiocb *req;
12240 hlist_for_each_entry(req, list, hash_node)
12241 seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
12242 task_work_pending(req->task));
12245 seq_puts(m, "CqOverflowList:\n");
12246 list_for_each_entry(ocqe, &ctx->cq_overflow_list, list) {
12247 struct io_uring_cqe *cqe = &ocqe->cqe;
12249 seq_printf(m, " user_data=%llu, res=%d, flags=%x\n",
12250 cqe->user_data, cqe->res, cqe->flags);
12254 spin_unlock(&ctx->completion_lock);
12257 static __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
12259 struct io_ring_ctx *ctx = f->private_data;
12261 if (percpu_ref_tryget(&ctx->refs)) {
12262 __io_uring_show_fdinfo(ctx, m);
12263 percpu_ref_put(&ctx->refs);
12268 static const struct file_operations io_uring_fops = {
12269 .release = io_uring_release,
12270 .mmap = io_uring_mmap,
12272 .get_unmapped_area = io_uring_nommu_get_unmapped_area,
12273 .mmap_capabilities = io_uring_nommu_mmap_capabilities,
12275 .poll = io_uring_poll,
12276 #ifdef CONFIG_PROC_FS
12277 .show_fdinfo = io_uring_show_fdinfo,
12281 static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx,
12282 struct io_uring_params *p)
12284 struct io_rings *rings;
12285 size_t size, sq_array_offset;
12287 /* make sure these are sane, as we already accounted them */
12288 ctx->sq_entries = p->sq_entries;
12289 ctx->cq_entries = p->cq_entries;
12291 size = rings_size(ctx, p->sq_entries, p->cq_entries, &sq_array_offset);
12292 if (size == SIZE_MAX)
12295 rings = io_mem_alloc(size);
12299 ctx->rings = rings;
12300 ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
12301 rings->sq_ring_mask = p->sq_entries - 1;
12302 rings->cq_ring_mask = p->cq_entries - 1;
12303 rings->sq_ring_entries = p->sq_entries;
12304 rings->cq_ring_entries = p->cq_entries;
12306 if (p->flags & IORING_SETUP_SQE128)
12307 size = array_size(2 * sizeof(struct io_uring_sqe), p->sq_entries);
12309 size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
12310 if (size == SIZE_MAX) {
12311 io_mem_free(ctx->rings);
12316 ctx->sq_sqes = io_mem_alloc(size);
12317 if (!ctx->sq_sqes) {
12318 io_mem_free(ctx->rings);
12326 static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
12330 fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
12334 ret = io_uring_add_tctx_node(ctx);
12339 fd_install(fd, file);
12344 * Allocate an anonymous fd, this is what constitutes the application
12345 * visible backing of an io_uring instance. The application mmaps this
12346 * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
12347 * we have to tie this fd to a socket for file garbage collection purposes.
12349 static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
12352 #if defined(CONFIG_UNIX)
12355 ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
12358 return ERR_PTR(ret);
12361 file = anon_inode_getfile_secure("[io_uring]", &io_uring_fops, ctx,
12362 O_RDWR | O_CLOEXEC, NULL);
12363 #if defined(CONFIG_UNIX)
12364 if (IS_ERR(file)) {
12365 sock_release(ctx->ring_sock);
12366 ctx->ring_sock = NULL;
12368 ctx->ring_sock->file = file;
12374 static __cold int io_uring_create(unsigned entries, struct io_uring_params *p,
12375 struct io_uring_params __user *params)
12377 struct io_ring_ctx *ctx;
12383 if (entries > IORING_MAX_ENTRIES) {
12384 if (!(p->flags & IORING_SETUP_CLAMP))
12386 entries = IORING_MAX_ENTRIES;
12390 * Use twice as many entries for the CQ ring. It's possible for the
12391 * application to drive a higher depth than the size of the SQ ring,
12392 * since the sqes are only used at submission time. This allows for
12393 * some flexibility in overcommitting a bit. If the application has
12394 * set IORING_SETUP_CQSIZE, it will have passed in the desired number
12395 * of CQ ring entries manually.
12397 p->sq_entries = roundup_pow_of_two(entries);
12398 if (p->flags & IORING_SETUP_CQSIZE) {
12400 * If IORING_SETUP_CQSIZE is set, we do the same roundup
12401 * to a power-of-two, if it isn't already. We do NOT impose
12402 * any cq vs sq ring sizing.
12404 if (!p->cq_entries)
12406 if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
12407 if (!(p->flags & IORING_SETUP_CLAMP))
12409 p->cq_entries = IORING_MAX_CQ_ENTRIES;
12411 p->cq_entries = roundup_pow_of_two(p->cq_entries);
12412 if (p->cq_entries < p->sq_entries)
12415 p->cq_entries = 2 * p->sq_entries;
12418 ctx = io_ring_ctx_alloc(p);
12423 * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
12424 * space applications don't need to do io completion events
12425 * polling again, they can rely on io_sq_thread to do polling
12426 * work, which can reduce cpu usage and uring_lock contention.
12428 if (ctx->flags & IORING_SETUP_IOPOLL &&
12429 !(ctx->flags & IORING_SETUP_SQPOLL))
12430 ctx->syscall_iopoll = 1;
12432 ctx->compat = in_compat_syscall();
12433 if (!capable(CAP_IPC_LOCK))
12434 ctx->user = get_uid(current_user());
12437 * For SQPOLL, we just need a wakeup, always. For !SQPOLL, if
12438 * COOP_TASKRUN is set, then IPIs are never needed by the app.
12441 if (ctx->flags & IORING_SETUP_SQPOLL) {
12442 /* IPI related flags don't make sense with SQPOLL */
12443 if (ctx->flags & (IORING_SETUP_COOP_TASKRUN |
12444 IORING_SETUP_TASKRUN_FLAG))
12446 ctx->notify_method = TWA_SIGNAL_NO_IPI;
12447 } else if (ctx->flags & IORING_SETUP_COOP_TASKRUN) {
12448 ctx->notify_method = TWA_SIGNAL_NO_IPI;
12450 if (ctx->flags & IORING_SETUP_TASKRUN_FLAG)
12452 ctx->notify_method = TWA_SIGNAL;
12456 * This is just grabbed for accounting purposes. When a process exits,
12457 * the mm is exited and dropped before the files, hence we need to hang
12458 * on to this mm purely for the purposes of being able to unaccount
12459 * memory (locked/pinned vm). It's not used for anything else.
12461 mmgrab(current->mm);
12462 ctx->mm_account = current->mm;
12464 ret = io_allocate_scq_urings(ctx, p);
12468 ret = io_sq_offload_create(ctx, p);
12471 /* always set a rsrc node */
12472 ret = io_rsrc_node_switch_start(ctx);
12475 io_rsrc_node_switch(ctx, NULL);
12477 memset(&p->sq_off, 0, sizeof(p->sq_off));
12478 p->sq_off.head = offsetof(struct io_rings, sq.head);
12479 p->sq_off.tail = offsetof(struct io_rings, sq.tail);
12480 p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
12481 p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
12482 p->sq_off.flags = offsetof(struct io_rings, sq_flags);
12483 p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
12484 p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
12486 memset(&p->cq_off, 0, sizeof(p->cq_off));
12487 p->cq_off.head = offsetof(struct io_rings, cq.head);
12488 p->cq_off.tail = offsetof(struct io_rings, cq.tail);
12489 p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
12490 p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
12491 p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
12492 p->cq_off.cqes = offsetof(struct io_rings, cqes);
12493 p->cq_off.flags = offsetof(struct io_rings, cq_flags);
12495 p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
12496 IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
12497 IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
12498 IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
12499 IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS |
12500 IORING_FEAT_RSRC_TAGS | IORING_FEAT_CQE_SKIP |
12501 IORING_FEAT_LINKED_FILE;
12503 if (copy_to_user(params, p, sizeof(*p))) {
12508 file = io_uring_get_file(ctx);
12509 if (IS_ERR(file)) {
12510 ret = PTR_ERR(file);
12515 * Install ring fd as the very last thing, so we don't risk someone
12516 * having closed it before we finish setup
12518 ret = io_uring_install_fd(ctx, file);
12520 /* fput will clean it up */
12525 trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
12528 io_ring_ctx_wait_and_kill(ctx);
12533 * Sets up an aio uring context, and returns the fd. Applications asks for a
12534 * ring size, we return the actual sq/cq ring sizes (among other things) in the
12535 * params structure passed in.
12537 static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
12539 struct io_uring_params p;
12542 if (copy_from_user(&p, params, sizeof(p)))
12544 for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
12549 if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
12550 IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
12551 IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
12552 IORING_SETUP_R_DISABLED | IORING_SETUP_SUBMIT_ALL |
12553 IORING_SETUP_COOP_TASKRUN | IORING_SETUP_TASKRUN_FLAG |
12554 IORING_SETUP_SQE128 | IORING_SETUP_CQE32))
12557 return io_uring_create(entries, &p, params);
12560 SYSCALL_DEFINE2(io_uring_setup, u32, entries,
12561 struct io_uring_params __user *, params)
12563 return io_uring_setup(entries, params);
12566 static __cold int io_probe(struct io_ring_ctx *ctx, void __user *arg,
12569 struct io_uring_probe *p;
12573 size = struct_size(p, ops, nr_args);
12574 if (size == SIZE_MAX)
12576 p = kzalloc(size, GFP_KERNEL);
12581 if (copy_from_user(p, arg, size))
12584 if (memchr_inv(p, 0, size))
12587 p->last_op = IORING_OP_LAST - 1;
12588 if (nr_args > IORING_OP_LAST)
12589 nr_args = IORING_OP_LAST;
12591 for (i = 0; i < nr_args; i++) {
12593 if (!io_op_defs[i].not_supported)
12594 p->ops[i].flags = IO_URING_OP_SUPPORTED;
12599 if (copy_to_user(arg, p, size))
12606 static int io_register_personality(struct io_ring_ctx *ctx)
12608 const struct cred *creds;
12612 creds = get_current_cred();
12614 ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
12615 XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
12623 static __cold int io_register_restrictions(struct io_ring_ctx *ctx,
12624 void __user *arg, unsigned int nr_args)
12626 struct io_uring_restriction *res;
12630 /* Restrictions allowed only if rings started disabled */
12631 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
12634 /* We allow only a single restrictions registration */
12635 if (ctx->restrictions.registered)
12638 if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
12641 size = array_size(nr_args, sizeof(*res));
12642 if (size == SIZE_MAX)
12645 res = memdup_user(arg, size);
12647 return PTR_ERR(res);
12651 for (i = 0; i < nr_args; i++) {
12652 switch (res[i].opcode) {
12653 case IORING_RESTRICTION_REGISTER_OP:
12654 if (res[i].register_op >= IORING_REGISTER_LAST) {
12659 __set_bit(res[i].register_op,
12660 ctx->restrictions.register_op);
12662 case IORING_RESTRICTION_SQE_OP:
12663 if (res[i].sqe_op >= IORING_OP_LAST) {
12668 __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
12670 case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
12671 ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
12673 case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
12674 ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
12683 /* Reset all restrictions if an error happened */
12685 memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
12687 ctx->restrictions.registered = true;
12693 static int io_register_enable_rings(struct io_ring_ctx *ctx)
12695 if (!(ctx->flags & IORING_SETUP_R_DISABLED))
12698 if (ctx->restrictions.registered)
12699 ctx->restricted = 1;
12701 ctx->flags &= ~IORING_SETUP_R_DISABLED;
12702 if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
12703 wake_up(&ctx->sq_data->wait);
12707 static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
12708 struct io_uring_rsrc_update2 *up,
12714 if (check_add_overflow(up->offset, nr_args, &tmp))
12716 err = io_rsrc_node_switch_start(ctx);
12721 case IORING_RSRC_FILE:
12722 return __io_sqe_files_update(ctx, up, nr_args);
12723 case IORING_RSRC_BUFFER:
12724 return __io_sqe_buffers_update(ctx, up, nr_args);
12729 static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
12732 struct io_uring_rsrc_update2 up;
12736 memset(&up, 0, sizeof(up));
12737 if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update)))
12739 if (up.resv || up.resv2)
12741 return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args);
12744 static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
12745 unsigned size, unsigned type)
12747 struct io_uring_rsrc_update2 up;
12749 if (size != sizeof(up))
12751 if (copy_from_user(&up, arg, sizeof(up)))
12753 if (!up.nr || up.resv || up.resv2)
12755 return __io_register_rsrc_update(ctx, type, &up, up.nr);
12758 static __cold int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
12759 unsigned int size, unsigned int type)
12761 struct io_uring_rsrc_register rr;
12763 /* keep it extendible */
12764 if (size != sizeof(rr))
12767 memset(&rr, 0, sizeof(rr));
12768 if (copy_from_user(&rr, arg, size))
12770 if (!rr.nr || rr.resv2)
12772 if (rr.flags & ~IORING_RSRC_REGISTER_SPARSE)
12776 case IORING_RSRC_FILE:
12777 if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data)
12779 return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data),
12780 rr.nr, u64_to_user_ptr(rr.tags));
12781 case IORING_RSRC_BUFFER:
12782 if (rr.flags & IORING_RSRC_REGISTER_SPARSE && rr.data)
12784 return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data),
12785 rr.nr, u64_to_user_ptr(rr.tags));
12790 static __cold int io_register_iowq_aff(struct io_ring_ctx *ctx,
12791 void __user *arg, unsigned len)
12793 struct io_uring_task *tctx = current->io_uring;
12794 cpumask_var_t new_mask;
12797 if (!tctx || !tctx->io_wq)
12800 if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
12803 cpumask_clear(new_mask);
12804 if (len > cpumask_size())
12805 len = cpumask_size();
12807 if (in_compat_syscall()) {
12808 ret = compat_get_bitmap(cpumask_bits(new_mask),
12809 (const compat_ulong_t __user *)arg,
12810 len * 8 /* CHAR_BIT */);
12812 ret = copy_from_user(new_mask, arg, len);
12816 free_cpumask_var(new_mask);
12820 ret = io_wq_cpu_affinity(tctx->io_wq, new_mask);
12821 free_cpumask_var(new_mask);
12825 static __cold int io_unregister_iowq_aff(struct io_ring_ctx *ctx)
12827 struct io_uring_task *tctx = current->io_uring;
12829 if (!tctx || !tctx->io_wq)
12832 return io_wq_cpu_affinity(tctx->io_wq, NULL);
12835 static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
12837 __must_hold(&ctx->uring_lock)
12839 struct io_tctx_node *node;
12840 struct io_uring_task *tctx = NULL;
12841 struct io_sq_data *sqd = NULL;
12842 __u32 new_count[2];
12845 if (copy_from_user(new_count, arg, sizeof(new_count)))
12847 for (i = 0; i < ARRAY_SIZE(new_count); i++)
12848 if (new_count[i] > INT_MAX)
12851 if (ctx->flags & IORING_SETUP_SQPOLL) {
12852 sqd = ctx->sq_data;
12855 * Observe the correct sqd->lock -> ctx->uring_lock
12856 * ordering. Fine to drop uring_lock here, we hold
12857 * a ref to the ctx.
12859 refcount_inc(&sqd->refs);
12860 mutex_unlock(&ctx->uring_lock);
12861 mutex_lock(&sqd->lock);
12862 mutex_lock(&ctx->uring_lock);
12864 tctx = sqd->thread->io_uring;
12867 tctx = current->io_uring;
12870 BUILD_BUG_ON(sizeof(new_count) != sizeof(ctx->iowq_limits));
12872 for (i = 0; i < ARRAY_SIZE(new_count); i++)
12874 ctx->iowq_limits[i] = new_count[i];
12875 ctx->iowq_limits_set = true;
12877 if (tctx && tctx->io_wq) {
12878 ret = io_wq_max_workers(tctx->io_wq, new_count);
12882 memset(new_count, 0, sizeof(new_count));
12886 mutex_unlock(&sqd->lock);
12887 io_put_sq_data(sqd);
12890 if (copy_to_user(arg, new_count, sizeof(new_count)))
12893 /* that's it for SQPOLL, only the SQPOLL task creates requests */
12897 /* now propagate the restriction to all registered users */
12898 list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
12899 struct io_uring_task *tctx = node->task->io_uring;
12901 if (WARN_ON_ONCE(!tctx->io_wq))
12904 for (i = 0; i < ARRAY_SIZE(new_count); i++)
12905 new_count[i] = ctx->iowq_limits[i];
12906 /* ignore errors, it always returns zero anyway */
12907 (void)io_wq_max_workers(tctx->io_wq, new_count);
12912 mutex_unlock(&sqd->lock);
12913 io_put_sq_data(sqd);
12918 static int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg)
12920 struct io_uring_buf_ring *br;
12921 struct io_uring_buf_reg reg;
12922 struct io_buffer_list *bl;
12923 struct page **pages;
12926 if (copy_from_user(®, arg, sizeof(reg)))
12929 if (reg.pad || reg.resv[0] || reg.resv[1] || reg.resv[2])
12931 if (!reg.ring_addr)
12933 if (reg.ring_addr & ~PAGE_MASK)
12935 if (!is_power_of_2(reg.ring_entries))
12938 /* cannot disambiguate full vs empty due to head/tail size */
12939 if (reg.ring_entries >= 65536)
12942 if (unlikely(reg.bgid < BGID_ARRAY && !ctx->io_bl)) {
12943 int ret = io_init_bl_list(ctx);
12948 bl = io_buffer_get_list(ctx, reg.bgid);
12950 /* if mapped buffer ring OR classic exists, don't allow */
12951 if (bl->buf_nr_pages || !list_empty(&bl->buf_list))
12954 bl = kzalloc(sizeof(*bl), GFP_KERNEL);
12959 pages = io_pin_pages(reg.ring_addr,
12960 struct_size(br, bufs, reg.ring_entries),
12962 if (IS_ERR(pages)) {
12964 return PTR_ERR(pages);
12967 br = page_address(pages[0]);
12968 bl->buf_pages = pages;
12969 bl->buf_nr_pages = nr_pages;
12970 bl->nr_entries = reg.ring_entries;
12972 bl->mask = reg.ring_entries - 1;
12973 io_buffer_add_list(ctx, bl, reg.bgid);
12977 static int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg)
12979 struct io_uring_buf_reg reg;
12980 struct io_buffer_list *bl;
12982 if (copy_from_user(®, arg, sizeof(reg)))
12984 if (reg.pad || reg.resv[0] || reg.resv[1] || reg.resv[2])
12987 bl = io_buffer_get_list(ctx, reg.bgid);
12990 if (!bl->buf_nr_pages)
12993 __io_remove_buffers(ctx, bl, -1U);
12994 if (bl->bgid >= BGID_ARRAY) {
12995 xa_erase(&ctx->io_bl_xa, bl->bgid);
13001 static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
13002 void __user *arg, unsigned nr_args)
13003 __releases(ctx->uring_lock)
13004 __acquires(ctx->uring_lock)
13009 * We're inside the ring mutex, if the ref is already dying, then
13010 * someone else killed the ctx or is already going through
13011 * io_uring_register().
13013 if (percpu_ref_is_dying(&ctx->refs))
13016 if (ctx->restricted) {
13017 if (opcode >= IORING_REGISTER_LAST)
13019 opcode = array_index_nospec(opcode, IORING_REGISTER_LAST);
13020 if (!test_bit(opcode, ctx->restrictions.register_op))
13025 case IORING_REGISTER_BUFFERS:
13029 ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL);
13031 case IORING_UNREGISTER_BUFFERS:
13033 if (arg || nr_args)
13035 ret = io_sqe_buffers_unregister(ctx);
13037 case IORING_REGISTER_FILES:
13041 ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
13043 case IORING_UNREGISTER_FILES:
13045 if (arg || nr_args)
13047 ret = io_sqe_files_unregister(ctx);
13049 case IORING_REGISTER_FILES_UPDATE:
13050 ret = io_register_files_update(ctx, arg, nr_args);
13052 case IORING_REGISTER_EVENTFD:
13056 ret = io_eventfd_register(ctx, arg, 0);
13058 case IORING_REGISTER_EVENTFD_ASYNC:
13062 ret = io_eventfd_register(ctx, arg, 1);
13064 case IORING_UNREGISTER_EVENTFD:
13066 if (arg || nr_args)
13068 ret = io_eventfd_unregister(ctx);
13070 case IORING_REGISTER_PROBE:
13072 if (!arg || nr_args > 256)
13074 ret = io_probe(ctx, arg, nr_args);
13076 case IORING_REGISTER_PERSONALITY:
13078 if (arg || nr_args)
13080 ret = io_register_personality(ctx);
13082 case IORING_UNREGISTER_PERSONALITY:
13086 ret = io_unregister_personality(ctx, nr_args);
13088 case IORING_REGISTER_ENABLE_RINGS:
13090 if (arg || nr_args)
13092 ret = io_register_enable_rings(ctx);
13094 case IORING_REGISTER_RESTRICTIONS:
13095 ret = io_register_restrictions(ctx, arg, nr_args);
13097 case IORING_REGISTER_FILES2:
13098 ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE);
13100 case IORING_REGISTER_FILES_UPDATE2:
13101 ret = io_register_rsrc_update(ctx, arg, nr_args,
13104 case IORING_REGISTER_BUFFERS2:
13105 ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER);
13107 case IORING_REGISTER_BUFFERS_UPDATE:
13108 ret = io_register_rsrc_update(ctx, arg, nr_args,
13109 IORING_RSRC_BUFFER);
13111 case IORING_REGISTER_IOWQ_AFF:
13113 if (!arg || !nr_args)
13115 ret = io_register_iowq_aff(ctx, arg, nr_args);
13117 case IORING_UNREGISTER_IOWQ_AFF:
13119 if (arg || nr_args)
13121 ret = io_unregister_iowq_aff(ctx);
13123 case IORING_REGISTER_IOWQ_MAX_WORKERS:
13125 if (!arg || nr_args != 2)
13127 ret = io_register_iowq_max_workers(ctx, arg);
13129 case IORING_REGISTER_RING_FDS:
13130 ret = io_ringfd_register(ctx, arg, nr_args);
13132 case IORING_UNREGISTER_RING_FDS:
13133 ret = io_ringfd_unregister(ctx, arg, nr_args);
13135 case IORING_REGISTER_PBUF_RING:
13137 if (!arg || nr_args != 1)
13139 ret = io_register_pbuf_ring(ctx, arg);
13141 case IORING_UNREGISTER_PBUF_RING:
13143 if (!arg || nr_args != 1)
13145 ret = io_unregister_pbuf_ring(ctx, arg);
13155 SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
13156 void __user *, arg, unsigned int, nr_args)
13158 struct io_ring_ctx *ctx;
13167 if (f.file->f_op != &io_uring_fops)
13170 ctx = f.file->private_data;
13172 io_run_task_work();
13174 mutex_lock(&ctx->uring_lock);
13175 ret = __io_uring_register(ctx, opcode, arg, nr_args);
13176 mutex_unlock(&ctx->uring_lock);
13177 trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs, ret);
13183 static int __init io_uring_init(void)
13185 #define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
13186 BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
13187 BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
13190 #define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
13191 __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
13192 BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
13193 BUILD_BUG_SQE_ELEM(0, __u8, opcode);
13194 BUILD_BUG_SQE_ELEM(1, __u8, flags);
13195 BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
13196 BUILD_BUG_SQE_ELEM(4, __s32, fd);
13197 BUILD_BUG_SQE_ELEM(8, __u64, off);
13198 BUILD_BUG_SQE_ELEM(8, __u64, addr2);
13199 BUILD_BUG_SQE_ELEM(16, __u64, addr);
13200 BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
13201 BUILD_BUG_SQE_ELEM(24, __u32, len);
13202 BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
13203 BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
13204 BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
13205 BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
13206 BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
13207 BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
13208 BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
13209 BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
13210 BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
13211 BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
13212 BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
13213 BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
13214 BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
13215 BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
13216 BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
13217 BUILD_BUG_SQE_ELEM(32, __u64, user_data);
13218 BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
13219 BUILD_BUG_SQE_ELEM(40, __u16, buf_group);
13220 BUILD_BUG_SQE_ELEM(42, __u16, personality);
13221 BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
13222 BUILD_BUG_SQE_ELEM(44, __u32, file_index);
13223 BUILD_BUG_SQE_ELEM(48, __u64, addr3);
13225 BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=
13226 sizeof(struct io_uring_rsrc_update));
13227 BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) >
13228 sizeof(struct io_uring_rsrc_update2));
13230 /* ->buf_index is u16 */
13231 BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16));
13232 BUILD_BUG_ON(BGID_ARRAY * sizeof(struct io_buffer_list) > PAGE_SIZE);
13233 BUILD_BUG_ON(offsetof(struct io_uring_buf_ring, bufs) != 0);
13234 BUILD_BUG_ON(offsetof(struct io_uring_buf, resv) !=
13235 offsetof(struct io_uring_buf_ring, tail));
13237 /* should fit into one byte */
13238 BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));
13239 BUILD_BUG_ON(SQE_COMMON_FLAGS >= (1 << 8));
13240 BUILD_BUG_ON((SQE_VALID_FLAGS | SQE_COMMON_FLAGS) != SQE_VALID_FLAGS);
13242 BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
13243 BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int));
13245 BUILD_BUG_ON(sizeof(atomic_t) != sizeof(u32));
13247 BUILD_BUG_ON(sizeof(struct io_uring_cmd) > 64);
13249 req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
13253 __initcall(io_uring_init);