include/uapi/linux/io_uring.h

   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 #define IORING_SETUP_R_DISABLED (1U << 6)       /* start with ring disabled */
  99
 100 enum {
 101         IORING_OP_NOP,
 102         IORING_OP_READV,
 103         IORING_OP_WRITEV,
 104         IORING_OP_FSYNC,
 105         IORING_OP_READ_FIXED,
 106         IORING_OP_WRITE_FIXED,
 107         IORING_OP_POLL_ADD,
 108         IORING_OP_POLL_REMOVE,
 109         IORING_OP_SYNC_FILE_RANGE,
 110         IORING_OP_SENDMSG,
 111         IORING_OP_RECVMSG,
 112         IORING_OP_TIMEOUT,
 113         IORING_OP_TIMEOUT_REMOVE,
 114         IORING_OP_ACCEPT,
 115         IORING_OP_ASYNC_CANCEL,
 116         IORING_OP_LINK_TIMEOUT,
 117         IORING_OP_CONNECT,
 118         IORING_OP_FALLOCATE,
 119         IORING_OP_OPENAT,
 120         IORING_OP_CLOSE,
 121         IORING_OP_FILES_UPDATE,
 122         IORING_OP_STATX,
 123         IORING_OP_READ,
 124         IORING_OP_WRITE,
 125         IORING_OP_FADVISE,
 126         IORING_OP_MADVISE,
 127         IORING_OP_SEND,
 128         IORING_OP_RECV,
 129         IORING_OP_OPENAT2,
 130         IORING_OP_EPOLL_CTL,
 131         IORING_OP_SPLICE,
 132         IORING_OP_PROVIDE_BUFFERS,
 133         IORING_OP_REMOVE_BUFFERS,
 134         IORING_OP_TEE,
 135         IORING_OP_SHUTDOWN,
 136
 137         /* this goes last, obviously */
 138         IORING_OP_LAST,
 139 };
 140
 141 /*
 142  * sqe->fsync_flags
 143  */
 144 #define IORING_FSYNC_DATASYNC   (1U << 0)
 145
 146 /*
 147  * sqe->timeout_flags
 148  */
 149 #define IORING_TIMEOUT_ABS      (1U << 0)
 150
 151 /*
 152  * sqe->splice_flags
 153  * extends splice(2) flags
 154  */
 155 #define SPLICE_F_FD_IN_FIXED    (1U << 31) /* the last bit of __u32 */
 156
 157 /*
 158  * IO completion data structure (Completion Queue Entry)
 159  */
 160 struct io_uring_cqe {
 161         __u64   user_data;      /* sqe->data submission passed back */
 162         __s32   res;            /* result code for this event */
 163         __u32   flags;
 164 };
 165
 166 /*
 167  * cqe->flags
 168  *
 169  * IORING_CQE_F_BUFFER  If set, the upper 16 bits are the buffer ID
 170  */
 171 #define IORING_CQE_F_BUFFER             (1U << 0)
 172
 173 enum {
 174         IORING_CQE_BUFFER_SHIFT         = 16,
 175 };
 176
 177 /*
 178  * Magic offsets for the application to mmap the data it needs
 179  */
 180 #define IORING_OFF_SQ_RING              0ULL
 181 #define IORING_OFF_CQ_RING              0x8000000ULL
 182 #define IORING_OFF_SQES                 0x10000000ULL
 183
 184 /*
 185  * Filled with the offset for mmap(2)
 186  */
 187 struct io_sqring_offsets {
 188         __u32 head;
 189         __u32 tail;
 190         __u32 ring_mask;
 191         __u32 ring_entries;
 192         __u32 flags;
 193         __u32 dropped;
 194         __u32 array;
 195         __u32 resv1;
 196         __u64 resv2;
 197 };
 198
 199 /*
 200  * sq_ring->flags
 201  */
 202 #define IORING_SQ_NEED_WAKEUP   (1U << 0) /* needs io_uring_enter wakeup */
 203 #define IORING_SQ_CQ_OVERFLOW   (1U << 1) /* CQ ring is overflown */
 204
 205 struct io_cqring_offsets {
 206         __u32 head;
 207         __u32 tail;
 208         __u32 ring_mask;
 209         __u32 ring_entries;
 210         __u32 overflow;
 211         __u32 cqes;
 212         __u32 flags;
 213         __u32 resv1;
 214         __u64 resv2;
 215 };
 216
 217 /*
 218  * cq_ring->flags
 219  */
 220
 221 /* disable eventfd notifications */
 222 #define IORING_CQ_EVENTFD_DISABLED      (1U << 0)
 223
 224 /*
 225  * io_uring_enter(2) flags
 226  */
 227 #define IORING_ENTER_GETEVENTS  (1U << 0)
 228 #define IORING_ENTER_SQ_WAKEUP  (1U << 1)
 229 #define IORING_ENTER_SQ_WAIT    (1U << 2)
 230
 231 /*
 232  * Passed in for io_uring_setup(2). Copied back with updated info on success
 233  */
 234 struct io_uring_params {
 235         __u32 sq_entries;
 236         __u32 cq_entries;
 237         __u32 flags;
 238         __u32 sq_thread_cpu;
 239         __u32 sq_thread_idle;
 240         __u32 features;
 241         __u32 wq_fd;
 242         __u32 resv[3];
 243         struct io_sqring_offsets sq_off;
 244         struct io_cqring_offsets cq_off;
 245 };
 246
 247 /*
 248  * io_uring_params->features flags
 249  */
 250 #define IORING_FEAT_SINGLE_MMAP         (1U << 0)
 251 #define IORING_FEAT_NODROP              (1U << 1)
 252 #define IORING_FEAT_SUBMIT_STABLE       (1U << 2)
 253 #define IORING_FEAT_RW_CUR_POS          (1U << 3)
 254 #define IORING_FEAT_CUR_PERSONALITY     (1U << 4)
 255 #define IORING_FEAT_FAST_POLL           (1U << 5)
 256 #define IORING_FEAT_POLL_32BITS         (1U << 6)
 257 #define IORING_FEAT_SQPOLL_NONFIXED     (1U << 7)
 258
 259 /*
 260  * io_uring_register(2) opcodes and arguments
 261  */
 262 enum {
 263         IORING_REGISTER_BUFFERS                 = 0,
 264         IORING_UNREGISTER_BUFFERS               = 1,
 265         IORING_REGISTER_FILES                   = 2,
 266         IORING_UNREGISTER_FILES                 = 3,
 267         IORING_REGISTER_EVENTFD                 = 4,
 268         IORING_UNREGISTER_EVENTFD               = 5,
 269         IORING_REGISTER_FILES_UPDATE            = 6,
 270         IORING_REGISTER_EVENTFD_ASYNC           = 7,
 271         IORING_REGISTER_PROBE                   = 8,
 272         IORING_REGISTER_PERSONALITY             = 9,
 273         IORING_UNREGISTER_PERSONALITY           = 10,
 274         IORING_REGISTER_RESTRICTIONS            = 11,
 275         IORING_REGISTER_ENABLE_RINGS            = 12,
 276
 277         /* this goes last */
 278         IORING_REGISTER_LAST
 279 };
 280
 281 struct io_uring_files_update {
 282         __u32 offset;
 283         __u32 resv;
 284         __aligned_u64 /* __s32 * */ fds;
 285 };
 286
 287 #define IO_URING_OP_SUPPORTED   (1U << 0)
 288
 289 struct io_uring_probe_op {
 290         __u8 op;
 291         __u8 resv;
 292         __u16 flags;    /* IO_URING_OP_* flags */
 293         __u32 resv2;
 294 };
 295
 296 struct io_uring_probe {
 297         __u8 last_op;   /* last opcode supported */
 298         __u8 ops_len;   /* length of ops[] array below */
 299         __u16 resv;
 300         __u32 resv2[3];
 301         struct io_uring_probe_op ops[0];
 302 };
 303
 304 struct io_uring_restriction {
 305         __u16 opcode;
 306         union {
 307                 __u8 register_op; /* IORING_RESTRICTION_REGISTER_OP */
 308                 __u8 sqe_op;      /* IORING_RESTRICTION_SQE_OP */
 309                 __u8 sqe_flags;   /* IORING_RESTRICTION_SQE_FLAGS_* */
 310         };
 311         __u8 resv;
 312         __u32 resv2[3];
 313 };
 314
 315 /*
 316  * io_uring_restriction->opcode values
 317  */
 318 enum {
 319         /* Allow an io_uring_register(2) opcode */
 320         IORING_RESTRICTION_REGISTER_OP          = 0,
 321
 322         /* Allow an sqe opcode */
 323         IORING_RESTRICTION_SQE_OP               = 1,
 324
 325         /* Allow sqe flags */
 326         IORING_RESTRICTION_SQE_FLAGS_ALLOWED    = 2,
 327
 328         /* Require sqe flags (these flags must be set on each submission) */
 329         IORING_RESTRICTION_SQE_FLAGS_REQUIRED   = 3,
 330
 331         IORING_RESTRICTION_LAST
 332 };
 333
 334 #endif