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1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2/*
3 * Header file for the io_uring interface.
4 *
5 * Copyright (C) 2019 Jens Axboe
6 * Copyright (C) 2019 Christoph Hellwig
7 */
8#ifndef LINUX_IO_URING_H
9#define LINUX_IO_URING_H
10
11#include <linux/fs.h>
12#include <linux/types.h>
13
14/*
15 * IO submission data structure (Submission Queue Entry)
16 */
17struct io_uring_sqe {
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 union {
23 __u64 off; /* offset into file */
24 __u64 addr2;
25 };
26 __u64 addr; /* pointer to buffer or iovecs */
27 __u32 len; /* buffer size or number of iovecs */
28 union {
29 __kernel_rwf_t rw_flags;
30 __u32 fsync_flags;
31 __u16 poll_events;
32 __u32 sync_range_flags;
33 __u32 msg_flags;
34 __u32 timeout_flags;
35 __u32 accept_flags;
36 __u32 cancel_flags;
37 __u32 open_flags;
38 __u32 statx_flags;
39 __u32 fadvise_advice;
40 };
41 __u64 user_data; /* data to be passed back at completion time */
42 union {
43 struct {
44 /* index into fixed buffers, if used */
45 __u16 buf_index;
46 /* personality to use, if used */
47 __u16 personality;
48 };
49 __u64 __pad2[3];
50 };
51};
52
53enum {
54 IOSQE_FIXED_FILE_BIT,
55 IOSQE_IO_DRAIN_BIT,
56 IOSQE_IO_LINK_BIT,
57 IOSQE_IO_HARDLINK_BIT,
58 IOSQE_ASYNC_BIT,
59};
60
61/*
62 * sqe->flags
63 */
64/* use fixed fileset */
65#define IOSQE_FIXED_FILE (1U << IOSQE_FIXED_FILE_BIT)
66/* issue after inflight IO */
67#define IOSQE_IO_DRAIN (1U << IOSQE_IO_DRAIN_BIT)
68/* links next sqe */
69#define IOSQE_IO_LINK (1U << IOSQE_IO_LINK_BIT)
70/* like LINK, but stronger */
71#define IOSQE_IO_HARDLINK (1U << IOSQE_IO_HARDLINK_BIT)
72/* always go async */
73#define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT)
74
75/*
76 * io_uring_setup() flags
77 */
78#define IORING_SETUP_IOPOLL (1U << 0) /* io_context is polled */
79#define IORING_SETUP_SQPOLL (1U << 1) /* SQ poll thread */
80#define IORING_SETUP_SQ_AFF (1U << 2) /* sq_thread_cpu is valid */
81#define IORING_SETUP_CQSIZE (1U << 3) /* app defines CQ size */
82#define IORING_SETUP_CLAMP (1U << 4) /* clamp SQ/CQ ring sizes */
83#define IORING_SETUP_ATTACH_WQ (1U << 5) /* attach to existing wq */
84
85enum {
86 IORING_OP_NOP,
87 IORING_OP_READV,
88 IORING_OP_WRITEV,
89 IORING_OP_FSYNC,
90 IORING_OP_READ_FIXED,
91 IORING_OP_WRITE_FIXED,
92 IORING_OP_POLL_ADD,
93 IORING_OP_POLL_REMOVE,
94 IORING_OP_SYNC_FILE_RANGE,
95 IORING_OP_SENDMSG,
96 IORING_OP_RECVMSG,
97 IORING_OP_TIMEOUT,
98 IORING_OP_TIMEOUT_REMOVE,
99 IORING_OP_ACCEPT,
100 IORING_OP_ASYNC_CANCEL,
101 IORING_OP_LINK_TIMEOUT,
102 IORING_OP_CONNECT,
103 IORING_OP_FALLOCATE,
104 IORING_OP_OPENAT,
105 IORING_OP_CLOSE,
106 IORING_OP_FILES_UPDATE,
107 IORING_OP_STATX,
108 IORING_OP_READ,
109 IORING_OP_WRITE,
110 IORING_OP_FADVISE,
111 IORING_OP_MADVISE,
112 IORING_OP_SEND,
113 IORING_OP_RECV,
114 IORING_OP_OPENAT2,
115 IORING_OP_EPOLL_CTL,
116
117 /* this goes last, obviously */
118 IORING_OP_LAST,
119};
120
121/*
122 * sqe->fsync_flags
123 */
124#define IORING_FSYNC_DATASYNC (1U << 0)
125
126/*
127 * sqe->timeout_flags
128 */
129#define IORING_TIMEOUT_ABS (1U << 0)
130
131/*
132 * IO completion data structure (Completion Queue Entry)
133 */
134struct io_uring_cqe {
135 __u64 user_data; /* sqe->data submission passed back */
136 __s32 res; /* result code for this event */
137 __u32 flags;
138};
139
140/*
141 * Magic offsets for the application to mmap the data it needs
142 */
143#define IORING_OFF_SQ_RING 0ULL
144#define IORING_OFF_CQ_RING 0x8000000ULL
145#define IORING_OFF_SQES 0x10000000ULL
146
147/*
148 * Filled with the offset for mmap(2)
149 */
150struct io_sqring_offsets {
151 __u32 head;
152 __u32 tail;
153 __u32 ring_mask;
154 __u32 ring_entries;
155 __u32 flags;
156 __u32 dropped;
157 __u32 array;
158 __u32 resv1;
159 __u64 resv2;
160};
161
162/*
163 * sq_ring->flags
164 */
165#define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */
166
167struct io_cqring_offsets {
168 __u32 head;
169 __u32 tail;
170 __u32 ring_mask;
171 __u32 ring_entries;
172 __u32 overflow;
173 __u32 cqes;
174 __u64 resv[2];
175};
176
177/*
178 * io_uring_enter(2) flags
179 */
180#define IORING_ENTER_GETEVENTS (1U << 0)
181#define IORING_ENTER_SQ_WAKEUP (1U << 1)
182
183/*
184 * Passed in for io_uring_setup(2). Copied back with updated info on success
185 */
186struct io_uring_params {
187 __u32 sq_entries;
188 __u32 cq_entries;
189 __u32 flags;
190 __u32 sq_thread_cpu;
191 __u32 sq_thread_idle;
192 __u32 features;
193 __u32 wq_fd;
194 __u32 resv[3];
195 struct io_sqring_offsets sq_off;
196 struct io_cqring_offsets cq_off;
197};
198
199/*
200 * io_uring_params->features flags
201 */
202#define IORING_FEAT_SINGLE_MMAP (1U << 0)
203#define IORING_FEAT_NODROP (1U << 1)
204#define IORING_FEAT_SUBMIT_STABLE (1U << 2)
205#define IORING_FEAT_RW_CUR_POS (1U << 3)
206#define IORING_FEAT_CUR_PERSONALITY (1U << 4)
207
208/*
209 * io_uring_register(2) opcodes and arguments
210 */
211#define IORING_REGISTER_BUFFERS 0
212#define IORING_UNREGISTER_BUFFERS 1
213#define IORING_REGISTER_FILES 2
214#define IORING_UNREGISTER_FILES 3
215#define IORING_REGISTER_EVENTFD 4
216#define IORING_UNREGISTER_EVENTFD 5
217#define IORING_REGISTER_FILES_UPDATE 6
218#define IORING_REGISTER_EVENTFD_ASYNC 7
219#define IORING_REGISTER_PROBE 8
220#define IORING_REGISTER_PERSONALITY 9
221#define IORING_UNREGISTER_PERSONALITY 10
222
223struct io_uring_files_update {
224 __u32 offset;
225 __u32 resv;
226 __aligned_u64 /* __s32 * */ fds;
227};
228
229#define IO_URING_OP_SUPPORTED (1U << 0)
230
231struct io_uring_probe_op {
232 __u8 op;
233 __u8 resv;
234 __u16 flags; /* IO_URING_OP_* flags */
235 __u32 resv2;
236};
237
238struct io_uring_probe {
239 __u8 last_op; /* last opcode supported */
240 __u8 ops_len; /* length of ops[] array below */
241 __u16 resv;
242 __u32 resv2[3];
243 struct io_uring_probe_op ops[0];
244};
245
246#endif