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 struct { 26 __u32 cmd_op; 27 __u32 __pad1; 28 }; 29 }; 30 union { 31 __u64 addr; /* pointer to buffer or iovecs */ 32 __u64 splice_off_in; 33 }; 34 __u32 len; /* buffer size or number of iovecs */ 35 union { 36 __kernel_rwf_t rw_flags; 37 __u32 fsync_flags; 38 __u16 poll_events; /* compatibility */ 39 __u32 poll32_events; /* word-reversed for BE */ 40 __u32 sync_range_flags; 41 __u32 msg_flags; 42 __u32 timeout_flags; 43 __u32 accept_flags; 44 __u32 cancel_flags; 45 __u32 open_flags; 46 __u32 statx_flags; 47 __u32 fadvise_advice; 48 __u32 splice_flags; 49 __u32 rename_flags; 50 __u32 unlink_flags; 51 __u32 hardlink_flags; 52 __u32 xattr_flags; 53 }; 54 __u64 user_data; /* data to be passed back at completion time */ 55 /* pack this to avoid bogus arm OABI complaints */ 56 union { 57 /* index into fixed buffers, if used */ 58 __u16 buf_index; 59 /* for grouped buffer selection */ 60 __u16 buf_group; 61 } __attribute__((packed)); 62 /* personality to use, if used */ 63 __u16 personality; 64 union { 65 __s32 splice_fd_in; 66 __u32 file_index; 67 }; 68 union { 69 struct { 70 __u64 addr3; 71 __u64 __pad2[1]; 72 }; 73 /* 74 * If the ring is initialized with IORING_SETUP_SQE128, then 75 * this field is used for 80 bytes of arbitrary command data 76 */ 77 __u8 cmd[0]; 78 }; 79 }; 80 81 /* 82 * If sqe->file_index is set to this for opcodes that instantiate a new 83 * direct descriptor (like openat/openat2/accept), then io_uring will allocate 84 * an available direct descriptor instead of having the application pass one 85 * in. The picked direct descriptor will be returned in cqe->res, or -ENFILE 86 * if the space is full. 87 */ 88 #define IORING_FILE_INDEX_ALLOC (~0U) 89 90 enum { 91 IOSQE_FIXED_FILE_BIT, 92 IOSQE_IO_DRAIN_BIT, 93 IOSQE_IO_LINK_BIT, 94 IOSQE_IO_HARDLINK_BIT, 95 IOSQE_ASYNC_BIT, 96 IOSQE_BUFFER_SELECT_BIT, 97 IOSQE_CQE_SKIP_SUCCESS_BIT, 98 }; 99 100 /* 101 * sqe->flags 102 */ 103 /* use fixed fileset */ 104 #define IOSQE_FIXED_FILE (1U << IOSQE_FIXED_FILE_BIT) 105 /* issue after inflight IO */ 106 #define IOSQE_IO_DRAIN (1U << IOSQE_IO_DRAIN_BIT) 107 /* links next sqe */ 108 #define IOSQE_IO_LINK (1U << IOSQE_IO_LINK_BIT) 109 /* like LINK, but stronger */ 110 #define IOSQE_IO_HARDLINK (1U << IOSQE_IO_HARDLINK_BIT) 111 /* always go async */ 112 #define IOSQE_ASYNC (1U << IOSQE_ASYNC_BIT) 113 /* select buffer from sqe->buf_group */ 114 #define IOSQE_BUFFER_SELECT (1U << IOSQE_BUFFER_SELECT_BIT) 115 /* don't post CQE if request succeeded */ 116 #define IOSQE_CQE_SKIP_SUCCESS (1U << IOSQE_CQE_SKIP_SUCCESS_BIT) 117 118 /* 119 * io_uring_setup() flags 120 */ 121 #define IORING_SETUP_IOPOLL (1U << 0) /* io_context is polled */ 122 #define IORING_SETUP_SQPOLL (1U << 1) /* SQ poll thread */ 123 #define IORING_SETUP_SQ_AFF (1U << 2) /* sq_thread_cpu is valid */ 124 #define IORING_SETUP_CQSIZE (1U << 3) /* app defines CQ size */ 125 #define IORING_SETUP_CLAMP (1U << 4) /* clamp SQ/CQ ring sizes */ 126 #define IORING_SETUP_ATTACH_WQ (1U << 5) /* attach to existing wq */ 127 #define IORING_SETUP_R_DISABLED (1U << 6) /* start with ring disabled */ 128 #define IORING_SETUP_SUBMIT_ALL (1U << 7) /* continue submit on error */ 129 /* 130 * Cooperative task running. When requests complete, they often require 131 * forcing the submitter to transition to the kernel to complete. If this 132 * flag is set, work will be done when the task transitions anyway, rather 133 * than force an inter-processor interrupt reschedule. This avoids interrupting 134 * a task running in userspace, and saves an IPI. 135 */ 136 #define IORING_SETUP_COOP_TASKRUN (1U << 8) 137 /* 138 * If COOP_TASKRUN is set, get notified if task work is available for 139 * running and a kernel transition would be needed to run it. This sets 140 * IORING_SQ_TASKRUN in the sq ring flags. Not valid with COOP_TASKRUN. 141 */ 142 #define IORING_SETUP_TASKRUN_FLAG (1U << 9) 143 144 #define IORING_SETUP_SQE128 (1U << 10) /* SQEs are 128 byte */ 145 #define IORING_SETUP_CQE32 (1U << 11) /* CQEs are 32 byte */ 146 147 enum io_uring_op { 148 IORING_OP_NOP, 149 IORING_OP_READV, 150 IORING_OP_WRITEV, 151 IORING_OP_FSYNC, 152 IORING_OP_READ_FIXED, 153 IORING_OP_WRITE_FIXED, 154 IORING_OP_POLL_ADD, 155 IORING_OP_POLL_REMOVE, 156 IORING_OP_SYNC_FILE_RANGE, 157 IORING_OP_SENDMSG, 158 IORING_OP_RECVMSG, 159 IORING_OP_TIMEOUT, 160 IORING_OP_TIMEOUT_REMOVE, 161 IORING_OP_ACCEPT, 162 IORING_OP_ASYNC_CANCEL, 163 IORING_OP_LINK_TIMEOUT, 164 IORING_OP_CONNECT, 165 IORING_OP_FALLOCATE, 166 IORING_OP_OPENAT, 167 IORING_OP_CLOSE, 168 IORING_OP_FILES_UPDATE, 169 IORING_OP_STATX, 170 IORING_OP_READ, 171 IORING_OP_WRITE, 172 IORING_OP_FADVISE, 173 IORING_OP_MADVISE, 174 IORING_OP_SEND, 175 IORING_OP_RECV, 176 IORING_OP_OPENAT2, 177 IORING_OP_EPOLL_CTL, 178 IORING_OP_SPLICE, 179 IORING_OP_PROVIDE_BUFFERS, 180 IORING_OP_REMOVE_BUFFERS, 181 IORING_OP_TEE, 182 IORING_OP_SHUTDOWN, 183 IORING_OP_RENAMEAT, 184 IORING_OP_UNLINKAT, 185 IORING_OP_MKDIRAT, 186 IORING_OP_SYMLINKAT, 187 IORING_OP_LINKAT, 188 IORING_OP_MSG_RING, 189 IORING_OP_FSETXATTR, 190 IORING_OP_SETXATTR, 191 IORING_OP_FGETXATTR, 192 IORING_OP_GETXATTR, 193 IORING_OP_SOCKET, 194 IORING_OP_URING_CMD, 195 196 /* this goes last, obviously */ 197 IORING_OP_LAST, 198 }; 199 200 /* 201 * sqe->fsync_flags 202 */ 203 #define IORING_FSYNC_DATASYNC (1U << 0) 204 205 /* 206 * sqe->timeout_flags 207 */ 208 #define IORING_TIMEOUT_ABS (1U << 0) 209 #define IORING_TIMEOUT_UPDATE (1U << 1) 210 #define IORING_TIMEOUT_BOOTTIME (1U << 2) 211 #define IORING_TIMEOUT_REALTIME (1U << 3) 212 #define IORING_LINK_TIMEOUT_UPDATE (1U << 4) 213 #define IORING_TIMEOUT_ETIME_SUCCESS (1U << 5) 214 #define IORING_TIMEOUT_CLOCK_MASK (IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME) 215 #define IORING_TIMEOUT_UPDATE_MASK (IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE) 216 /* 217 * sqe->splice_flags 218 * extends splice(2) flags 219 */ 220 #define SPLICE_F_FD_IN_FIXED (1U << 31) /* the last bit of __u32 */ 221 222 /* 223 * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the 224 * command flags for POLL_ADD are stored in sqe->len. 225 * 226 * IORING_POLL_ADD_MULTI Multishot poll. Sets IORING_CQE_F_MORE if 227 * the poll handler will continue to report 228 * CQEs on behalf of the same SQE. 229 * 230 * IORING_POLL_UPDATE Update existing poll request, matching 231 * sqe->addr as the old user_data field. 232 */ 233 #define IORING_POLL_ADD_MULTI (1U << 0) 234 #define IORING_POLL_UPDATE_EVENTS (1U << 1) 235 #define IORING_POLL_UPDATE_USER_DATA (1U << 2) 236 237 /* 238 * ASYNC_CANCEL flags. 239 * 240 * IORING_ASYNC_CANCEL_ALL Cancel all requests that match the given key 241 * IORING_ASYNC_CANCEL_FD Key off 'fd' for cancelation rather than the 242 * request 'user_data' 243 * IORING_ASYNC_CANCEL_ANY Match any request 244 */ 245 #define IORING_ASYNC_CANCEL_ALL (1U << 0) 246 #define IORING_ASYNC_CANCEL_FD (1U << 1) 247 #define IORING_ASYNC_CANCEL_ANY (1U << 2) 248 249 /* 250 * send/sendmsg and recv/recvmsg flags (sqe->ioprio) 251 * 252 * IORING_RECVSEND_POLL_FIRST If set, instead of first attempting to send 253 * or receive and arm poll if that yields an 254 * -EAGAIN result, arm poll upfront and skip 255 * the initial transfer attempt. 256 */ 257 #define IORING_RECVSEND_POLL_FIRST (1U << 0) 258 259 /* 260 * accept flags stored in sqe->ioprio 261 */ 262 #define IORING_ACCEPT_MULTISHOT (1U << 0) 263 264 /* 265 * IO completion data structure (Completion Queue Entry) 266 */ 267 struct io_uring_cqe { 268 __u64 user_data; /* sqe->data submission passed back */ 269 __s32 res; /* result code for this event */ 270 __u32 flags; 271 272 /* 273 * If the ring is initialized with IORING_SETUP_CQE32, then this field 274 * contains 16-bytes of padding, doubling the size of the CQE. 275 */ 276 __u64 big_cqe[]; 277 }; 278 279 /* 280 * cqe->flags 281 * 282 * IORING_CQE_F_BUFFER If set, the upper 16 bits are the buffer ID 283 * IORING_CQE_F_MORE If set, parent SQE will generate more CQE entries 284 * IORING_CQE_F_SOCK_NONEMPTY If set, more data to read after socket recv 285 */ 286 #define IORING_CQE_F_BUFFER (1U << 0) 287 #define IORING_CQE_F_MORE (1U << 1) 288 #define IORING_CQE_F_SOCK_NONEMPTY (1U << 2) 289 290 enum { 291 IORING_CQE_BUFFER_SHIFT = 16, 292 }; 293 294 /* 295 * Magic offsets for the application to mmap the data it needs 296 */ 297 #define IORING_OFF_SQ_RING 0ULL 298 #define IORING_OFF_CQ_RING 0x8000000ULL 299 #define IORING_OFF_SQES 0x10000000ULL 300 301 /* 302 * Filled with the offset for mmap(2) 303 */ 304 struct io_sqring_offsets { 305 __u32 head; 306 __u32 tail; 307 __u32 ring_mask; 308 __u32 ring_entries; 309 __u32 flags; 310 __u32 dropped; 311 __u32 array; 312 __u32 resv1; 313 __u64 resv2; 314 }; 315 316 /* 317 * sq_ring->flags 318 */ 319 #define IORING_SQ_NEED_WAKEUP (1U << 0) /* needs io_uring_enter wakeup */ 320 #define IORING_SQ_CQ_OVERFLOW (1U << 1) /* CQ ring is overflown */ 321 #define IORING_SQ_TASKRUN (1U << 2) /* task should enter the kernel */ 322 323 struct io_cqring_offsets { 324 __u32 head; 325 __u32 tail; 326 __u32 ring_mask; 327 __u32 ring_entries; 328 __u32 overflow; 329 __u32 cqes; 330 __u32 flags; 331 __u32 resv1; 332 __u64 resv2; 333 }; 334 335 /* 336 * cq_ring->flags 337 */ 338 339 /* disable eventfd notifications */ 340 #define IORING_CQ_EVENTFD_DISABLED (1U << 0) 341 342 /* 343 * io_uring_enter(2) flags 344 */ 345 #define IORING_ENTER_GETEVENTS (1U << 0) 346 #define IORING_ENTER_SQ_WAKEUP (1U << 1) 347 #define IORING_ENTER_SQ_WAIT (1U << 2) 348 #define IORING_ENTER_EXT_ARG (1U << 3) 349 #define IORING_ENTER_REGISTERED_RING (1U << 4) 350 351 /* 352 * Passed in for io_uring_setup(2). Copied back with updated info on success 353 */ 354 struct io_uring_params { 355 __u32 sq_entries; 356 __u32 cq_entries; 357 __u32 flags; 358 __u32 sq_thread_cpu; 359 __u32 sq_thread_idle; 360 __u32 features; 361 __u32 wq_fd; 362 __u32 resv[3]; 363 struct io_sqring_offsets sq_off; 364 struct io_cqring_offsets cq_off; 365 }; 366 367 /* 368 * io_uring_params->features flags 369 */ 370 #define IORING_FEAT_SINGLE_MMAP (1U << 0) 371 #define IORING_FEAT_NODROP (1U << 1) 372 #define IORING_FEAT_SUBMIT_STABLE (1U << 2) 373 #define IORING_FEAT_RW_CUR_POS (1U << 3) 374 #define IORING_FEAT_CUR_PERSONALITY (1U << 4) 375 #define IORING_FEAT_FAST_POLL (1U << 5) 376 #define IORING_FEAT_POLL_32BITS (1U << 6) 377 #define IORING_FEAT_SQPOLL_NONFIXED (1U << 7) 378 #define IORING_FEAT_EXT_ARG (1U << 8) 379 #define IORING_FEAT_NATIVE_WORKERS (1U << 9) 380 #define IORING_FEAT_RSRC_TAGS (1U << 10) 381 #define IORING_FEAT_CQE_SKIP (1U << 11) 382 #define IORING_FEAT_LINKED_FILE (1U << 12) 383 384 /* 385 * io_uring_register(2) opcodes and arguments 386 */ 387 enum { 388 IORING_REGISTER_BUFFERS = 0, 389 IORING_UNREGISTER_BUFFERS = 1, 390 IORING_REGISTER_FILES = 2, 391 IORING_UNREGISTER_FILES = 3, 392 IORING_REGISTER_EVENTFD = 4, 393 IORING_UNREGISTER_EVENTFD = 5, 394 IORING_REGISTER_FILES_UPDATE = 6, 395 IORING_REGISTER_EVENTFD_ASYNC = 7, 396 IORING_REGISTER_PROBE = 8, 397 IORING_REGISTER_PERSONALITY = 9, 398 IORING_UNREGISTER_PERSONALITY = 10, 399 IORING_REGISTER_RESTRICTIONS = 11, 400 IORING_REGISTER_ENABLE_RINGS = 12, 401 402 /* extended with tagging */ 403 IORING_REGISTER_FILES2 = 13, 404 IORING_REGISTER_FILES_UPDATE2 = 14, 405 IORING_REGISTER_BUFFERS2 = 15, 406 IORING_REGISTER_BUFFERS_UPDATE = 16, 407 408 /* set/clear io-wq thread affinities */ 409 IORING_REGISTER_IOWQ_AFF = 17, 410 IORING_UNREGISTER_IOWQ_AFF = 18, 411 412 /* set/get max number of io-wq workers */ 413 IORING_REGISTER_IOWQ_MAX_WORKERS = 19, 414 415 /* register/unregister io_uring fd with the ring */ 416 IORING_REGISTER_RING_FDS = 20, 417 IORING_UNREGISTER_RING_FDS = 21, 418 419 /* register ring based provide buffer group */ 420 IORING_REGISTER_PBUF_RING = 22, 421 IORING_UNREGISTER_PBUF_RING = 23, 422 423 /* this goes last */ 424 IORING_REGISTER_LAST 425 }; 426 427 /* io-wq worker categories */ 428 enum { 429 IO_WQ_BOUND, 430 IO_WQ_UNBOUND, 431 }; 432 433 /* deprecated, see struct io_uring_rsrc_update */ 434 struct io_uring_files_update { 435 __u32 offset; 436 __u32 resv; 437 __aligned_u64 /* __s32 * */ fds; 438 }; 439 440 /* 441 * Register a fully sparse file space, rather than pass in an array of all 442 * -1 file descriptors. 443 */ 444 #define IORING_RSRC_REGISTER_SPARSE (1U << 0) 445 446 struct io_uring_rsrc_register { 447 __u32 nr; 448 __u32 flags; 449 __u64 resv2; 450 __aligned_u64 data; 451 __aligned_u64 tags; 452 }; 453 454 struct io_uring_rsrc_update { 455 __u32 offset; 456 __u32 resv; 457 __aligned_u64 data; 458 }; 459 460 struct io_uring_rsrc_update2 { 461 __u32 offset; 462 __u32 resv; 463 __aligned_u64 data; 464 __aligned_u64 tags; 465 __u32 nr; 466 __u32 resv2; 467 }; 468 469 /* Skip updating fd indexes set to this value in the fd table */ 470 #define IORING_REGISTER_FILES_SKIP (-2) 471 472 #define IO_URING_OP_SUPPORTED (1U << 0) 473 474 struct io_uring_probe_op { 475 __u8 op; 476 __u8 resv; 477 __u16 flags; /* IO_URING_OP_* flags */ 478 __u32 resv2; 479 }; 480 481 struct io_uring_probe { 482 __u8 last_op; /* last opcode supported */ 483 __u8 ops_len; /* length of ops[] array below */ 484 __u16 resv; 485 __u32 resv2[3]; 486 struct io_uring_probe_op ops[0]; 487 }; 488 489 struct io_uring_restriction { 490 __u16 opcode; 491 union { 492 __u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */ 493 __u8 sqe_op; /* IORING_RESTRICTION_SQE_OP */ 494 __u8 sqe_flags; /* IORING_RESTRICTION_SQE_FLAGS_* */ 495 }; 496 __u8 resv; 497 __u32 resv2[3]; 498 }; 499 500 struct io_uring_buf { 501 __u64 addr; 502 __u32 len; 503 __u16 bid; 504 __u16 resv; 505 }; 506 507 struct io_uring_buf_ring { 508 union { 509 /* 510 * To avoid spilling into more pages than we need to, the 511 * ring tail is overlaid with the io_uring_buf->resv field. 512 */ 513 struct { 514 __u64 resv1; 515 __u32 resv2; 516 __u16 resv3; 517 __u16 tail; 518 }; 519 struct io_uring_buf bufs[0]; 520 }; 521 }; 522 523 /* argument for IORING_(UN)REGISTER_PBUF_RING */ 524 struct io_uring_buf_reg { 525 __u64 ring_addr; 526 __u32 ring_entries; 527 __u16 bgid; 528 __u16 pad; 529 __u64 resv[3]; 530 }; 531 532 /* 533 * io_uring_restriction->opcode values 534 */ 535 enum { 536 /* Allow an io_uring_register(2) opcode */ 537 IORING_RESTRICTION_REGISTER_OP = 0, 538 539 /* Allow an sqe opcode */ 540 IORING_RESTRICTION_SQE_OP = 1, 541 542 /* Allow sqe flags */ 543 IORING_RESTRICTION_SQE_FLAGS_ALLOWED = 2, 544 545 /* Require sqe flags (these flags must be set on each submission) */ 546 IORING_RESTRICTION_SQE_FLAGS_REQUIRED = 3, 547 548 IORING_RESTRICTION_LAST 549 }; 550 551 struct io_uring_getevents_arg { 552 __u64 sigmask; 553 __u32 sigmask_sz; 554 __u32 pad; 555 __u64 ts; 556 }; 557 558 #endif 559