1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
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 */
26 __u64 addr; /* pointer to buffer or iovecs */
27 __u32 len; /* buffer size or number of iovecs */
29 __kernel_rwf_t rw_flags;
32 __u32 sync_range_flags;
41 __u64 user_data; /* data to be passed back at completion time */
43 __u16 buf_index; /* index into fixed buffers, if used */
52 IOSQE_IO_HARDLINK_BIT,
59 /* use fixed fileset */
60 #define IOSQE_FIXED_FILE (1U << IOSQE_FIXED_FILE_BIT)
61 /* issue after inflight IO */
62 #define IOSQE_IO_DRAIN (1U << IOSQE_IO_DRAIN_BIT)
64 #define IOSQE_IO_LINK (1U << IOSQE_IO_LINK_BIT)
65 /* like LINK, but stronger */
66 #define IOSQE_IO_HARDLINK (1U << IOSQE_IO_HARDLINK_BIT)
68 #define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT)
71 * io_uring_setup() flags
73 #define IORING_SETUP_IOPOLL (1U << 0) /* io_context is polled */
74 #define IORING_SETUP_SQPOLL (1U << 1) /* SQ poll thread */
75 #define IORING_SETUP_SQ_AFF (1U << 2) /* sq_thread_cpu is valid */
76 #define IORING_SETUP_CQSIZE (1U << 3) /* app defines CQ size */
77 #define IORING_SETUP_CLAMP (1U << 4) /* clamp SQ/CQ ring sizes */
85 IORING_OP_WRITE_FIXED,
87 IORING_OP_POLL_REMOVE,
88 IORING_OP_SYNC_FILE_RANGE,
92 IORING_OP_TIMEOUT_REMOVE,
94 IORING_OP_ASYNC_CANCEL,
95 IORING_OP_LINK_TIMEOUT,
100 IORING_OP_FILES_UPDATE,
110 /* this goes last, obviously */
117 #define IORING_FSYNC_DATASYNC (1U << 0)
122 #define IORING_TIMEOUT_ABS (1U << 0)
125 * IO completion data structure (Completion Queue Entry)
127 struct io_uring_cqe {
128 __u64 user_data; /* sqe->data submission passed back */
129 __s32 res; /* result code for this event */
134 * Magic offsets for the application to mmap the data it needs
136 #define IORING_OFF_SQ_RING 0ULL
137 #define IORING_OFF_CQ_RING 0x8000000ULL
138 #define IORING_OFF_SQES 0x10000000ULL
141 * Filled with the offset for mmap(2)
143 struct io_sqring_offsets {
158 #define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */
160 struct io_cqring_offsets {
171 * io_uring_enter(2) flags
173 #define IORING_ENTER_GETEVENTS (1U << 0)
174 #define IORING_ENTER_SQ_WAKEUP (1U << 1)
177 * Passed in for io_uring_setup(2). Copied back with updated info on success
179 struct io_uring_params {
184 __u32 sq_thread_idle;
187 struct io_sqring_offsets sq_off;
188 struct io_cqring_offsets cq_off;
192 * io_uring_params->features flags
194 #define IORING_FEAT_SINGLE_MMAP (1U << 0)
195 #define IORING_FEAT_NODROP (1U << 1)
196 #define IORING_FEAT_SUBMIT_STABLE (1U << 2)
197 #define IORING_FEAT_RW_CUR_POS (1U << 3)
200 * io_uring_register(2) opcodes and arguments
202 #define IORING_REGISTER_BUFFERS 0
203 #define IORING_UNREGISTER_BUFFERS 1
204 #define IORING_REGISTER_FILES 2
205 #define IORING_UNREGISTER_FILES 3
206 #define IORING_REGISTER_EVENTFD 4
207 #define IORING_UNREGISTER_EVENTFD 5
208 #define IORING_REGISTER_FILES_UPDATE 6
209 #define IORING_REGISTER_EVENTFD_ASYNC 7
210 #define IORING_REGISTER_PROBE 8
212 struct io_uring_files_update {
215 __aligned_u64 /* __s32 * */ fds;
218 #define IO_URING_OP_SUPPORTED (1U << 0)
220 struct io_uring_probe_op {
223 __u16 flags; /* IO_URING_OP_* flags */
227 struct io_uring_probe {
228 __u8 last_op; /* last opcode supported */
229 __u8 ops_len; /* length of ops[] array below */
232 struct io_uring_probe_op ops[0];