1 /* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR MIT */
3 * Header file for the io_uring interface.
5 * Copyright (C) 2019 Jens Axboe
6 * Copyright (C) 2019 Christoph Hellwig
8 #ifndef LINUX_IO_URING_H
9 #define LINUX_IO_URING_H
12 #include <linux/types.h>
15 * IO submission data structure (Submission Queue Entry)
18 __u8 opcode; /* type of operation for this sqe */
19 __u8 flags; /* IOSQE_ flags */
20 __u16 ioprio; /* ioprio for the request */
21 __s32 fd; /* file descriptor to do IO on */
23 __u64 off; /* offset into file */
27 __u64 addr; /* pointer to buffer or iovecs */
30 __u32 len; /* buffer size or number of iovecs */
32 __kernel_rwf_t rw_flags;
34 __u16 poll_events; /* compatibility */
35 __u32 poll32_events; /* word-reversed for BE */
36 __u32 sync_range_flags;
48 __u64 user_data; /* data to be passed back at completion time */
49 /* pack this to avoid bogus arm OABI complaints */
51 /* index into fixed buffers, if used */
53 /* for grouped buffer selection */
55 } __attribute__((packed));
56 /* personality to use, if used */
66 IOSQE_IO_HARDLINK_BIT,
68 IOSQE_BUFFER_SELECT_BIT,
74 /* use fixed fileset */
75 #define IOSQE_FIXED_FILE (1U << IOSQE_FIXED_FILE_BIT)
76 /* issue after inflight IO */
77 #define IOSQE_IO_DRAIN (1U << IOSQE_IO_DRAIN_BIT)
79 #define IOSQE_IO_LINK (1U << IOSQE_IO_LINK_BIT)
80 /* like LINK, but stronger */
81 #define IOSQE_IO_HARDLINK (1U << IOSQE_IO_HARDLINK_BIT)
83 #define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT)
84 /* select buffer from sqe->buf_group */
85 #define IOSQE_BUFFER_SELECT (1U << IOSQE_BUFFER_SELECT_BIT)
88 * io_uring_setup() flags
90 #define IORING_SETUP_IOPOLL (1U << 0) /* io_context is polled */
91 #define IORING_SETUP_SQPOLL (1U << 1) /* SQ poll thread */
92 #define IORING_SETUP_SQ_AFF (1U << 2) /* sq_thread_cpu is valid */
93 #define IORING_SETUP_CQSIZE (1U << 3) /* app defines CQ size */
94 #define IORING_SETUP_CLAMP (1U << 4) /* clamp SQ/CQ ring sizes */
95 #define IORING_SETUP_ATTACH_WQ (1U << 5) /* attach to existing wq */
96 #define IORING_SETUP_R_DISABLED (1U << 6) /* start with ring disabled */
103 IORING_OP_READ_FIXED,
104 IORING_OP_WRITE_FIXED,
106 IORING_OP_POLL_REMOVE,
107 IORING_OP_SYNC_FILE_RANGE,
111 IORING_OP_TIMEOUT_REMOVE,
113 IORING_OP_ASYNC_CANCEL,
114 IORING_OP_LINK_TIMEOUT,
119 IORING_OP_FILES_UPDATE,
130 IORING_OP_PROVIDE_BUFFERS,
131 IORING_OP_REMOVE_BUFFERS,
137 /* this goes last, obviously */
144 #define IORING_FSYNC_DATASYNC (1U << 0)
149 #define IORING_TIMEOUT_ABS (1U << 0)
150 #define IORING_TIMEOUT_UPDATE (1U << 1)
154 * extends splice(2) flags
156 #define SPLICE_F_FD_IN_FIXED (1U << 31) /* the last bit of __u32 */
159 * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the
160 * command flags for POLL_ADD are stored in sqe->len.
162 * IORING_POLL_ADD_MULTI Multishot poll. Sets IORING_CQE_F_MORE if
163 * the poll handler will continue to report
164 * CQEs on behalf of the same SQE.
166 * IORING_POLL_UPDATE Update existing poll request, matching
167 * sqe->addr as the old user_data field.
169 #define IORING_POLL_ADD_MULTI (1U << 0)
170 #define IORING_POLL_UPDATE_EVENTS (1U << 1)
171 #define IORING_POLL_UPDATE_USER_DATA (1U << 2)
174 * IO completion data structure (Completion Queue Entry)
176 struct io_uring_cqe {
177 __u64 user_data; /* sqe->data submission passed back */
178 __s32 res; /* result code for this event */
185 * IORING_CQE_F_BUFFER If set, the upper 16 bits are the buffer ID
186 * IORING_CQE_F_MORE If set, parent SQE will generate more CQE entries
188 #define IORING_CQE_F_BUFFER (1U << 0)
189 #define IORING_CQE_F_MORE (1U << 1)
192 IORING_CQE_BUFFER_SHIFT = 16,
196 * Magic offsets for the application to mmap the data it needs
198 #define IORING_OFF_SQ_RING 0ULL
199 #define IORING_OFF_CQ_RING 0x8000000ULL
200 #define IORING_OFF_SQES 0x10000000ULL
203 * Filled with the offset for mmap(2)
205 struct io_sqring_offsets {
220 #define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */
221 #define IORING_SQ_CQ_OVERFLOW (1U << 1) /* CQ ring is overflown */
223 struct io_cqring_offsets {
239 /* disable eventfd notifications */
240 #define IORING_CQ_EVENTFD_DISABLED (1U << 0)
243 * io_uring_enter(2) flags
245 #define IORING_ENTER_GETEVENTS (1U << 0)
246 #define IORING_ENTER_SQ_WAKEUP (1U << 1)
247 #define IORING_ENTER_SQ_WAIT (1U << 2)
248 #define IORING_ENTER_EXT_ARG (1U << 3)
251 * Passed in for io_uring_setup(2). Copied back with updated info on success
253 struct io_uring_params {
258 __u32 sq_thread_idle;
262 struct io_sqring_offsets sq_off;
263 struct io_cqring_offsets cq_off;
267 * io_uring_params->features flags
269 #define IORING_FEAT_SINGLE_MMAP (1U << 0)
270 #define IORING_FEAT_NODROP (1U << 1)
271 #define IORING_FEAT_SUBMIT_STABLE (1U << 2)
272 #define IORING_FEAT_RW_CUR_POS (1U << 3)
273 #define IORING_FEAT_CUR_PERSONALITY (1U << 4)
274 #define IORING_FEAT_FAST_POLL (1U << 5)
275 #define IORING_FEAT_POLL_32BITS (1U << 6)
276 #define IORING_FEAT_SQPOLL_NONFIXED (1U << 7)
277 #define IORING_FEAT_EXT_ARG (1U << 8)
278 #define IORING_FEAT_NATIVE_WORKERS (1U << 9)
279 #define IORING_FEAT_RSRC_TAGS (1U << 10)
282 * io_uring_register(2) opcodes and arguments
285 IORING_REGISTER_BUFFERS = 0,
286 IORING_UNREGISTER_BUFFERS = 1,
287 IORING_REGISTER_FILES = 2,
288 IORING_UNREGISTER_FILES = 3,
289 IORING_REGISTER_EVENTFD = 4,
290 IORING_UNREGISTER_EVENTFD = 5,
291 IORING_REGISTER_FILES_UPDATE = 6,
292 IORING_REGISTER_EVENTFD_ASYNC = 7,
293 IORING_REGISTER_PROBE = 8,
294 IORING_REGISTER_PERSONALITY = 9,
295 IORING_UNREGISTER_PERSONALITY = 10,
296 IORING_REGISTER_RESTRICTIONS = 11,
297 IORING_REGISTER_ENABLE_RINGS = 12,
299 /* extended with tagging */
300 IORING_REGISTER_FILES2 = 13,
301 IORING_REGISTER_FILES_UPDATE2 = 14,
302 IORING_REGISTER_BUFFERS2 = 15,
303 IORING_REGISTER_BUFFERS_UPDATE = 16,
305 /* set/clear io-wq thread affinities */
306 IORING_REGISTER_IOWQ_AFF = 17,
307 IORING_UNREGISTER_IOWQ_AFF = 18,
313 /* deprecated, see struct io_uring_rsrc_update */
314 struct io_uring_files_update {
317 __aligned_u64 /* __s32 * */ fds;
320 struct io_uring_rsrc_register {
328 struct io_uring_rsrc_update {
334 struct io_uring_rsrc_update2 {
343 /* Skip updating fd indexes set to this value in the fd table */
344 #define IORING_REGISTER_FILES_SKIP (-2)
346 #define IO_URING_OP_SUPPORTED (1U << 0)
348 struct io_uring_probe_op {
351 __u16 flags; /* IO_URING_OP_* flags */
355 struct io_uring_probe {
356 __u8 last_op; /* last opcode supported */
357 __u8 ops_len; /* length of ops[] array below */
360 struct io_uring_probe_op ops[0];
363 struct io_uring_restriction {
366 __u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */
367 __u8 sqe_op; /* IORING_RESTRICTION_SQE_OP */
368 __u8 sqe_flags; /* IORING_RESTRICTION_SQE_FLAGS_* */
375 * io_uring_restriction->opcode values
378 /* Allow an io_uring_register(2) opcode */
379 IORING_RESTRICTION_REGISTER_OP = 0,
381 /* Allow an sqe opcode */
382 IORING_RESTRICTION_SQE_OP = 1,
384 /* Allow sqe flags */
385 IORING_RESTRICTION_SQE_FLAGS_ALLOWED = 2,
387 /* Require sqe flags (these flags must be set on each submission) */
388 IORING_RESTRICTION_SQE_FLAGS_REQUIRED = 3,
390 IORING_RESTRICTION_LAST
393 struct io_uring_getevents_arg {