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; /* as of now unused */
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 __u16 buf_index; /* index into fixed buffers, if used */
34 __u64 data; /* data to be passed back at completion time */
40 #define IOSQE_FIXED_BUFFER (1 << 0) /* use fixed buffer */
43 * io_uring_setup() flags
45 #define IORING_SETUP_IOPOLL (1 << 0) /* io_context is polled */
46 #define IORING_SETUP_SQPOLL (1 << 1) /* SQ poll thread */
47 #define IORING_SETUP_SQ_AFF (1 << 2) /* sq_thread_cpu is valid */
49 #define IORING_OP_READV 1
50 #define IORING_OP_WRITEV 2
51 #define IORING_OP_FSYNC 3
52 #define IORING_OP_FDSYNC 4
55 * IO completion data structure (Completion Queue Entry)
58 __u64 data; /* sqe->data submission passed back */
59 __s32 res; /* result code for this event */
64 * io_uring_event->flags
66 #define IOCQE_FLAG_CACHEHIT (1 << 0) /* IO did not hit media */
69 * Magic offsets for the application to mmap the data it needs
71 #define IORING_OFF_SQ_RING 0ULL
72 #define IORING_OFF_CQ_RING 0x8000000ULL
73 #define IORING_OFF_SQES 0x10000000ULL
76 * Filled with the offset for mmap(2)
78 struct io_sqring_offsets {
89 #define IORING_SQ_NEED_WAKEUP (1 << 0) /* needs io_uring_enter wakeup */
91 struct io_cqring_offsets {
102 * io_uring_enter(2) flags
104 #define IORING_ENTER_GETEVENTS (1 << 0)
107 * Passed in for io_uring_setup(2). Copied back with updated info on success
109 struct io_uring_params {
115 struct io_sqring_offsets sq_off;
116 struct io_cqring_offsets cq_off;
120 * io_uring_register(2) opcodes and arguments
122 #define IORING_REGISTER_BUFFERS 0
123 #define IORING_UNREGISTER_BUFFERS 1
125 struct io_uring_register_buffers {
126 struct iovec *iovecs;