1 /* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR MIT */ 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 */ 17 struct 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 union { 27 __u64 addr; /* pointer to buffer or iovecs */ 28 __u64 splice_off_in; 29 }; 30 __u32 len; /* buffer size or number of iovecs */ 31 union { 32 __kernel_rwf_t rw_flags; 33 __u32 fsync_flags; 34 __u16 poll_events; /* compatibility */ 35 __u32 poll32_events; /* word-reversed for BE */ 36 __u32 sync_range_flags; 37 __u32 msg_flags; 38 __u32 timeout_flags; 39 __u32 accept_flags; 40 __u32 cancel_flags; 41 __u32 open_flags; 42 __u32 statx_flags; 43 __u32 fadvise_advice; 44 __u32 splice_flags; 45 }; 46 __u64 user_data; /* data to be passed back at completion time */ 47 union { 48 struct { 49 /* pack this to avoid bogus arm OABI complaints */ 50 union { 51 /* index into fixed buffers, if used */ 52 __u16 buf_index; 53 /* for grouped buffer selection */ 54 __u16 buf_group; 55 } __attribute__((packed)); 56 /* personality to use, if used */ 57 __u16 personality; 58 __s32 splice_fd_in; 59 }; 60 __u64 __pad2[3]; 61 }; 62 }; 63 64 enum { 65 IOSQE_FIXED_FILE_BIT, 66 IOSQE_IO_DRAIN_BIT, 67 IOSQE_IO_LINK_BIT, 68 IOSQE_IO_HARDLINK_BIT, 69 IOSQE_ASYNC_BIT, 70 IOSQE_BUFFER_SELECT_BIT, 71 }; 72 73 /* 74 * sqe->flags 75 */ 76 /* use fixed fileset */ 77 #define IOSQE_FIXED_FILE (1U << IOSQE_FIXED_FILE_BIT) 78 /* issue after inflight IO */ 79 #define IOSQE_IO_DRAIN (1U << IOSQE_IO_DRAIN_BIT) 80 /* links next sqe */ 81 #define IOSQE_IO_LINK (1U << IOSQE_IO_LINK_BIT) 82 /* like LINK, but stronger */ 83 #define IOSQE_IO_HARDLINK (1U << IOSQE_IO_HARDLINK_BIT) 84 /* always go async */ 85 #define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT) 86 /* select buffer from sqe->buf_group */ 87 #define IOSQE_BUFFER_SELECT (1U << IOSQE_BUFFER_SELECT_BIT) 88 89 /* 90 * io_uring_setup() flags 91 */ 92 #define IORING_SETUP_IOPOLL (1U << 0) /* io_context is polled */ 93 #define IORING_SETUP_SQPOLL (1U << 1) /* SQ poll thread */ 94 #define IORING_SETUP_SQ_AFF (1U << 2) /* sq_thread_cpu is valid */ 95 #define IORING_SETUP_CQSIZE (1U << 3) /* app defines CQ size */ 96 #define IORING_SETUP_CLAMP (1U << 4) /* clamp SQ/CQ ring sizes */ 97 #define IORING_SETUP_ATTACH_WQ (1U << 5) /* attach to existing wq */ 98 99 enum { 100 IORING_OP_NOP, 101 IORING_OP_READV, 102 IORING_OP_WRITEV, 103 IORING_OP_FSYNC, 104 IORING_OP_READ_FIXED, 105 IORING_OP_WRITE_FIXED, 106 IORING_OP_POLL_ADD, 107 IORING_OP_POLL_REMOVE, 108 IORING_OP_SYNC_FILE_RANGE, 109 IORING_OP_SENDMSG, 110 IORING_OP_RECVMSG, 111 IORING_OP_TIMEOUT, 112 IORING_OP_TIMEOUT_REMOVE, 113 IORING_OP_ACCEPT, 114 IORING_OP_ASYNC_CANCEL, 115 IORING_OP_LINK_TIMEOUT, 116 IORING_OP_CONNECT, 117 IORING_OP_FALLOCATE, 118 IORING_OP_OPENAT, 119 IORING_OP_CLOSE, 120 IORING_OP_FILES_UPDATE, 121 IORING_OP_STATX, 122 IORING_OP_READ, 123 IORING_OP_WRITE, 124 IORING_OP_FADVISE, 125 IORING_OP_MADVISE, 126 IORING_OP_SEND, 127 IORING_OP_RECV, 128 IORING_OP_OPENAT2, 129 IORING_OP_EPOLL_CTL, 130 IORING_OP_SPLICE, 131 IORING_OP_PROVIDE_BUFFERS, 132 IORING_OP_REMOVE_BUFFERS, 133 IORING_OP_TEE, 134 135 /* this goes last, obviously */ 136 IORING_OP_LAST, 137 }; 138 139 /* 140 * sqe->fsync_flags 141 */ 142 #define IORING_FSYNC_DATASYNC (1U << 0) 143 144 /* 145 * sqe->timeout_flags 146 */ 147 #define IORING_TIMEOUT_ABS (1U << 0) 148 149 /* 150 * sqe->splice_flags 151 * extends splice(2) flags 152 */ 153 #define SPLICE_F_FD_IN_FIXED (1U << 31) /* the last bit of __u32 */ 154 155 /* 156 * IO completion data structure (Completion Queue Entry) 157 */ 158 struct io_uring_cqe { 159 __u64 user_data; /* sqe->data submission passed back */ 160 __s32 res; /* result code for this event */ 161 __u32 flags; 162 }; 163 164 /* 165 * cqe->flags 166 * 167 * IORING_CQE_F_BUFFER If set, the upper 16 bits are the buffer ID 168 */ 169 #define IORING_CQE_F_BUFFER (1U << 0) 170 171 enum { 172 IORING_CQE_BUFFER_SHIFT = 16, 173 }; 174 175 /* 176 * Magic offsets for the application to mmap the data it needs 177 */ 178 #define IORING_OFF_SQ_RING 0ULL 179 #define IORING_OFF_CQ_RING 0x8000000ULL 180 #define IORING_OFF_SQES 0x10000000ULL 181 182 /* 183 * Filled with the offset for mmap(2) 184 */ 185 struct io_sqring_offsets { 186 __u32 head; 187 __u32 tail; 188 __u32 ring_mask; 189 __u32 ring_entries; 190 __u32 flags; 191 __u32 dropped; 192 __u32 array; 193 __u32 resv1; 194 __u64 resv2; 195 }; 196 197 /* 198 * sq_ring->flags 199 */ 200 #define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */ 201 #define IORING_SQ_CQ_OVERFLOW (1U << 1) /* CQ ring is overflown */ 202 203 struct io_cqring_offsets { 204 __u32 head; 205 __u32 tail; 206 __u32 ring_mask; 207 __u32 ring_entries; 208 __u32 overflow; 209 __u32 cqes; 210 __u32 flags; 211 __u32 resv1; 212 __u64 resv2; 213 }; 214 215 /* 216 * cq_ring->flags 217 */ 218 219 /* disable eventfd notifications */ 220 #define IORING_CQ_EVENTFD_DISABLED (1U << 0) 221 222 /* 223 * io_uring_enter(2) flags 224 */ 225 #define IORING_ENTER_GETEVENTS (1U << 0) 226 #define IORING_ENTER_SQ_WAKEUP (1U << 1) 227 228 /* 229 * Passed in for io_uring_setup(2). Copied back with updated info on success 230 */ 231 struct io_uring_params { 232 __u32 sq_entries; 233 __u32 cq_entries; 234 __u32 flags; 235 __u32 sq_thread_cpu; 236 __u32 sq_thread_idle; 237 __u32 features; 238 __u32 wq_fd; 239 __u32 resv[3]; 240 struct io_sqring_offsets sq_off; 241 struct io_cqring_offsets cq_off; 242 }; 243 244 /* 245 * io_uring_params->features flags 246 */ 247 #define IORING_FEAT_SINGLE_MMAP (1U << 0) 248 #define IORING_FEAT_NODROP (1U << 1) 249 #define IORING_FEAT_SUBMIT_STABLE (1U << 2) 250 #define IORING_FEAT_RW_CUR_POS (1U << 3) 251 #define IORING_FEAT_CUR_PERSONALITY (1U << 4) 252 #define IORING_FEAT_FAST_POLL (1U << 5) 253 #define IORING_FEAT_POLL_32BITS (1U << 6) 254 255 /* 256 * io_uring_register(2) opcodes and arguments 257 */ 258 #define IORING_REGISTER_BUFFERS 0 259 #define IORING_UNREGISTER_BUFFERS 1 260 #define IORING_REGISTER_FILES 2 261 #define IORING_UNREGISTER_FILES 3 262 #define IORING_REGISTER_EVENTFD 4 263 #define IORING_UNREGISTER_EVENTFD 5 264 #define IORING_REGISTER_FILES_UPDATE 6 265 #define IORING_REGISTER_EVENTFD_ASYNC 7 266 #define IORING_REGISTER_PROBE 8 267 #define IORING_REGISTER_PERSONALITY 9 268 #define IORING_UNREGISTER_PERSONALITY 10 269 270 struct io_uring_files_update { 271 __u32 offset; 272 __u32 resv; 273 __aligned_u64 /* __s32 * */ fds; 274 }; 275 276 #define IO_URING_OP_SUPPORTED (1U << 0) 277 278 struct io_uring_probe_op { 279 __u8 op; 280 __u8 resv; 281 __u16 flags; /* IO_URING_OP_* flags */ 282 __u32 resv2; 283 }; 284 285 struct io_uring_probe { 286 __u8 last_op; /* last opcode supported */ 287 __u8 ops_len; /* length of ops[] array below */ 288 __u16 resv; 289 __u32 resv2[3]; 290 struct io_uring_probe_op ops[0]; 291 }; 292 293 #endif 294