summaryrefslogtreecommitdiff
path: root/src/include/liburing/io_uring.h
blob: 7ae91dc85196e0cc43a6986edf7593a2914af750 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
 * Header file for the io_uring interface.
 *
 * Copyright (C) 2019 Jens Axboe
 * Copyright (C) 2019 Christoph Hellwig
 */
#ifndef LINUX_IO_URING_H
#define LINUX_IO_URING_H

#include <linux/fs.h>
#include <linux/types.h>

/*
 * IO submission data structure (Submission Queue Entry)
 */
struct io_uring_sqe {
	__u8	opcode;		/* type of operation for this sqe */
	__u8	flags;		/* IOSQE_ flags */
	__u16	ioprio;		/* ioprio for the request */
	__s32	fd;		/* file descriptor to do IO on */
	union {
		__u64	off;	/* offset into file */
		__u64	addr2;
	};
	__u64	addr;		/* pointer to buffer or iovecs */
	__u32	len;		/* buffer size or number of iovecs */
	union {
		__kernel_rwf_t	rw_flags;
		__u32		fsync_flags;
		__u16		poll_events;
		__u32		sync_range_flags;
		__u32		msg_flags;
		__u32		timeout_flags;
		__u32		accept_flags;
		__u32		cancel_flags;
	};
	__u64	user_data;	/* data to be passed back at completion time */
	union {
		__u16	buf_index;	/* index into fixed buffers, if used */
		__u64	__pad2[3];
	};
};

/*
 * sqe->flags
 */
#define IOSQE_FIXED_FILE	(1U << 0)	/* use fixed fileset */
#define IOSQE_IO_DRAIN		(1U << 1)	/* issue after inflight IO */
#define IOSQE_IO_LINK		(1U << 2)	/* links next sqe */

/*
 * io_uring_setup() flags
 */
#define IORING_SETUP_IOPOLL	(1U << 0)	/* io_context is polled */
#define IORING_SETUP_SQPOLL	(1U << 1)	/* SQ poll thread */
#define IORING_SETUP_SQ_AFF	(1U << 2)	/* sq_thread_cpu is valid */
#define IORING_SETUP_CQSIZE	(1U << 3)	/* app defines CQ size */
#define IORING_SETUP_CQ_NODROP	(1U << 4)	/* no CQ drops */

#define IORING_OP_NOP		0
#define IORING_OP_READV		1
#define IORING_OP_WRITEV	2
#define IORING_OP_FSYNC		3
#define IORING_OP_READ_FIXED	4
#define IORING_OP_WRITE_FIXED	5
#define IORING_OP_POLL_ADD	6
#define IORING_OP_POLL_REMOVE	7
#define IORING_OP_SYNC_FILE_RANGE	8
#define IORING_OP_SENDMSG	9
#define IORING_OP_RECVMSG	10
#define IORING_OP_TIMEOUT	11
#define IORING_OP_TIMEOUT_REMOVE	12
#define IORING_OP_ACCEPT	13
#define IORING_OP_ASYNC_CANCEL	14

/*
 * sqe->fsync_flags
 */
#define IORING_FSYNC_DATASYNC	(1U << 0)

/*
 * sqe->timeout_flags
 */
#define IORING_TIMEOUT_ABS	(1U << 0)

/*
 * IO completion data structure (Completion Queue Entry)
 */
struct io_uring_cqe {
	__u64	user_data;	/* sqe->data submission passed back */
	__s32	res;		/* result code for this event */
	__u32	flags;
};

/*
 * Magic offsets for the application to mmap the data it needs
 */
#define IORING_OFF_SQ_RING		0ULL
#define IORING_OFF_CQ_RING		0x8000000ULL
#define IORING_OFF_SQES			0x10000000ULL

/*
 * Filled with the offset for mmap(2)
 */
struct io_sqring_offsets {
	__u32 head;
	__u32 tail;
	__u32 ring_mask;
	__u32 ring_entries;
	__u32 flags;
	__u32 dropped;
	__u32 array;
	__u32 resv1;
	__u64 resv2;
};

/*
 * sq_ring->flags
 */
#define IORING_SQ_NEED_WAKEUP	(1U << 0) /* needs io_uring_enter wakeup */

struct io_cqring_offsets {
	__u32 head;
	__u32 tail;
	__u32 ring_mask;
	__u32 ring_entries;
	__u32 overflow;
	__u32 cqes;
	__u64 resv[2];
};

/*
 * io_uring_enter(2) flags
 */
#define IORING_ENTER_GETEVENTS	(1U << 0)
#define IORING_ENTER_SQ_WAKEUP	(1U << 1)

/*
 * Passed in for io_uring_setup(2). Copied back with updated info on success
 */
struct io_uring_params {
	__u32 sq_entries;
	__u32 cq_entries;
	__u32 flags;
	__u32 sq_thread_cpu;
	__u32 sq_thread_idle;
	__u32 features;
	__u32 resv[4];
	struct io_sqring_offsets sq_off;
	struct io_cqring_offsets cq_off;
};

/*
 * io_uring_params->features flags
 */
#define IORING_FEAT_SINGLE_MMAP		(1U << 0)

/*
 * io_uring_register(2) opcodes and arguments
 */
#define IORING_REGISTER_BUFFERS		0
#define IORING_UNREGISTER_BUFFERS	1
#define IORING_REGISTER_FILES		2
#define IORING_UNREGISTER_FILES		3
#define IORING_REGISTER_EVENTFD		4
#define IORING_UNREGISTER_EVENTFD	5
#define IORING_REGISTER_FILES_UPDATE	6

struct io_uring_files_update {
	__u32 offset;
	__s32 *fds;
};

#endif