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 */
22 __u64 off; /* offset into file */
24 void *addr; /* buffer or iovecs */
27 __u32 len; /* buffer size or number of iovecs */
29 __kernel_rwf_t rw_flags;
32 __u64 user_data; /* data to be passed back at completion time */
34 __u16 buf_index; /* index into fixed buffers, if used */
42 #define IOSQE_FIXED_FILE (1 << 0) /* use fixed fileset */
45 * io_uring_setup() flags
47 #define IORING_SETUP_IOPOLL (1 << 0) /* io_context is polled */
48 #define IORING_SETUP_SQPOLL (1 << 1) /* SQ poll thread */
49 #define IORING_SETUP_SQ_AFF (1 << 2) /* sq_thread_cpu is valid */
51 #define IORING_OP_NOP 0
52 #define IORING_OP_READV 1
53 #define IORING_OP_WRITEV 2
54 #define IORING_OP_FSYNC 3
55 #define IORING_OP_READ_FIXED 4
56 #define IORING_OP_WRITE_FIXED 5
61 #define IORING_FSYNC_DATASYNC (1 << 0)
64 * IO completion data structure (Completion Queue Entry)
67 __u64 user_data; /* sqe->data submission passed back */
68 __s32 res; /* result code for this event */
73 * io_uring_event->flags
75 #define IOCQE_FLAG_CACHEHIT (1 << 0) /* IO did not hit media */
78 * Magic offsets for the application to mmap the data it needs
80 #define IORING_OFF_SQ_RING 0ULL
81 #define IORING_OFF_CQ_RING 0x8000000ULL
82 #define IORING_OFF_SQES 0x10000000ULL
85 * Filled with the offset for mmap(2)
87 struct io_sqring_offsets {
101 #define IORING_SQ_NEED_WAKEUP (1 << 0) /* needs io_uring_enter wakeup */
103 struct io_cqring_offsets {
114 * io_uring_enter(2) flags
116 #define IORING_ENTER_GETEVENTS (1 << 0)
119 * Passed in for io_uring_setup(2). Copied back with updated info on success
121 struct io_uring_params {
127 struct io_sqring_offsets sq_off;
128 struct io_cqring_offsets cq_off;
132 * io_uring_register(2) opcodes and arguments
134 #define IORING_REGISTER_BUFFERS 0
135 #define IORING_UNREGISTER_BUFFERS 1
136 #define IORING_REGISTER_FILES 2
137 #define IORING_UNREGISTER_FILES 3
139 struct io_uring_register_buffers {
141 struct iovec *iovecs;
147 struct io_uring_register_files {