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 below */
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 */
41 #define IOSQE_FIXED_FILE (1 << 1) /* use fixed fileset */
44 * io_uring_setup() flags
46 #define IORING_SETUP_IOPOLL (1 << 0) /* io_context is polled */
47 #define IORING_SETUP_SQPOLL (1 << 1) /* SQ poll thread */
48 #define IORING_SETUP_SQ_AFF (1 << 2) /* sq_thread_cpu is valid */
50 #define IORING_OP_READV 1
51 #define IORING_OP_WRITEV 2
52 #define IORING_OP_FSYNC 3
53 #define IORING_OP_FDSYNC 4
56 * IO completion data structure (Completion Queue Entry)
59 __u64 data; /* sqe->data submission passed back */
60 __s32 res; /* result code for this event */
65 * io_uring_event->flags
67 #define IOCQE_FLAG_CACHEHIT (1 << 0) /* IO did not hit media */
70 * Magic offsets for the application to mmap the data it needs
72 #define IORING_OFF_SQ_RING 0ULL
73 #define IORING_OFF_CQ_RING 0x8000000ULL
74 #define IORING_OFF_SQES 0x10000000ULL
77 * Filled with the offset for mmap(2)
79 struct io_sqring_offsets {
90 #define IORING_SQ_NEED_WAKEUP (1 << 0) /* needs io_uring_enter wakeup */
92 struct io_cqring_offsets {
103 * io_uring_enter(2) flags
105 #define IORING_ENTER_GETEVENTS (1 << 0)
108 * Passed in for io_uring_setup(2). Copied back with updated info on success
110 struct io_uring_params {
116 struct io_sqring_offsets sq_off;
117 struct io_cqring_offsets cq_off;
121 * io_uring_register(2) opcodes and arguments
123 #define IORING_REGISTER_BUFFERS 0
124 #define IORING_UNREGISTER_BUFFERS 1
125 #define IORING_REGISTER_FILES 2
126 #define IORING_UNREGISTER_FILES 3
128 struct io_uring_register_buffers {
129 struct iovec *iovecs;
133 struct io_uring_register_files {