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The C and C++ Include Header Files
/usr/include/linux/ublk_cmd.h
$ cat -n /usr/include/linux/ublk_cmd.h 1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ 2 #ifndef USER_BLK_DRV_CMD_INC_H 3 #define USER_BLK_DRV_CMD_INC_H 4 5 #include <linux/types.h> 6 7 /* ublk server command definition */ 8 9 /* 10 * Admin commands, issued by ublk server, and handled by ublk driver. 11 * 12 * Legacy command definition, don't use in new application, and don't 13 * add new such definition any more 14 */ 15 #define UBLK_CMD_GET_QUEUE_AFFINITY 0x01 16 #define UBLK_CMD_GET_DEV_INFO 0x02 17 #define UBLK_CMD_ADD_DEV 0x04 18 #define UBLK_CMD_DEL_DEV 0x05 19 #define UBLK_CMD_START_DEV 0x06 20 #define UBLK_CMD_STOP_DEV 0x07 21 #define UBLK_CMD_SET_PARAMS 0x08 22 #define UBLK_CMD_GET_PARAMS 0x09 23 #define UBLK_CMD_START_USER_RECOVERY 0x10 24 #define UBLK_CMD_END_USER_RECOVERY 0x11 25 #define UBLK_CMD_GET_DEV_INFO2 0x12 26 27 /* Any new ctrl command should encode by __IO*() */ 28 #define UBLK_U_CMD_GET_QUEUE_AFFINITY \ 29 _IOR('u', UBLK_CMD_GET_QUEUE_AFFINITY, struct ublksrv_ctrl_cmd) 30 #define UBLK_U_CMD_GET_DEV_INFO \ 31 _IOR('u', UBLK_CMD_GET_DEV_INFO, struct ublksrv_ctrl_cmd) 32 #define UBLK_U_CMD_ADD_DEV \ 33 _IOWR('u', UBLK_CMD_ADD_DEV, struct ublksrv_ctrl_cmd) 34 #define UBLK_U_CMD_DEL_DEV \ 35 _IOWR('u', UBLK_CMD_DEL_DEV, struct ublksrv_ctrl_cmd) 36 #define UBLK_U_CMD_START_DEV \ 37 _IOWR('u', UBLK_CMD_START_DEV, struct ublksrv_ctrl_cmd) 38 #define UBLK_U_CMD_STOP_DEV \ 39 _IOWR('u', UBLK_CMD_STOP_DEV, struct ublksrv_ctrl_cmd) 40 #define UBLK_U_CMD_SET_PARAMS \ 41 _IOWR('u', UBLK_CMD_SET_PARAMS, struct ublksrv_ctrl_cmd) 42 #define UBLK_U_CMD_GET_PARAMS \ 43 _IOR('u', UBLK_CMD_GET_PARAMS, struct ublksrv_ctrl_cmd) 44 #define UBLK_U_CMD_START_USER_RECOVERY \ 45 _IOWR('u', UBLK_CMD_START_USER_RECOVERY, struct ublksrv_ctrl_cmd) 46 #define UBLK_U_CMD_END_USER_RECOVERY \ 47 _IOWR('u', UBLK_CMD_END_USER_RECOVERY, struct ublksrv_ctrl_cmd) 48 #define UBLK_U_CMD_GET_DEV_INFO2 \ 49 _IOR('u', UBLK_CMD_GET_DEV_INFO2, struct ublksrv_ctrl_cmd) 50 #define UBLK_U_CMD_GET_FEATURES \ 51 _IOR('u', 0x13, struct ublksrv_ctrl_cmd) 52 53 /* 54 * 64bits are enough now, and it should be easy to extend in case of 55 * running out of feature flags 56 */ 57 #define UBLK_FEATURES_LEN 8 58 59 /* 60 * IO commands, issued by ublk server, and handled by ublk driver. 61 * 62 * FETCH_REQ: issued via sqe(URING_CMD) beforehand for fetching IO request 63 * from ublk driver, should be issued only when starting device. After 64 * the associated cqe is returned, request's tag can be retrieved via 65 * cqe->userdata. 66 * 67 * COMMIT_AND_FETCH_REQ: issued via sqe(URING_CMD) after ublkserver handled 68 * this IO request, request's handling result is committed to ublk 69 * driver, meantime FETCH_REQ is piggyback, and FETCH_REQ has to be 70 * handled before completing io request. 71 * 72 * NEED_GET_DATA: only used for write requests to set io addr and copy data 73 * When NEED_GET_DATA is set, ublksrv has to issue UBLK_IO_NEED_GET_DATA 74 * command after ublk driver returns UBLK_IO_RES_NEED_GET_DATA. 75 * 76 * It is only used if ublksrv set UBLK_F_NEED_GET_DATA flag 77 * while starting a ublk device. 78 */ 79 80 /* 81 * Legacy IO command definition, don't use in new application, and don't 82 * add new such definition any more 83 */ 84 #define UBLK_IO_FETCH_REQ 0x20 85 #define UBLK_IO_COMMIT_AND_FETCH_REQ 0x21 86 #define UBLK_IO_NEED_GET_DATA 0x22 87 88 /* Any new IO command should encode by __IOWR() */ 89 #define UBLK_U_IO_FETCH_REQ \ 90 _IOWR('u', UBLK_IO_FETCH_REQ, struct ublksrv_io_cmd) 91 #define UBLK_U_IO_COMMIT_AND_FETCH_REQ \ 92 _IOWR('u', UBLK_IO_COMMIT_AND_FETCH_REQ, struct ublksrv_io_cmd) 93 #define UBLK_U_IO_NEED_GET_DATA \ 94 _IOWR('u', UBLK_IO_NEED_GET_DATA, struct ublksrv_io_cmd) 95 96 /* only ABORT means that no re-fetch */ 97 #define UBLK_IO_RES_OK 0 98 #define UBLK_IO_RES_NEED_GET_DATA 1 99 #define UBLK_IO_RES_ABORT (-ENODEV) 100 101 #define UBLKSRV_CMD_BUF_OFFSET 0 102 #define UBLKSRV_IO_BUF_OFFSET 0x80000000 103 104 /* tag bit is 16bit, so far limit at most 4096 IOs for each queue */ 105 #define UBLK_MAX_QUEUE_DEPTH 4096 106 107 /* single IO buffer max size is 32MB */ 108 #define UBLK_IO_BUF_OFF 0 109 #define UBLK_IO_BUF_BITS 25 110 #define UBLK_IO_BUF_BITS_MASK ((1ULL << UBLK_IO_BUF_BITS) - 1) 111 112 /* so at most 64K IOs for each queue */ 113 #define UBLK_TAG_OFF UBLK_IO_BUF_BITS 114 #define UBLK_TAG_BITS 16 115 #define UBLK_TAG_BITS_MASK ((1ULL << UBLK_TAG_BITS) - 1) 116 117 /* max 4096 queues */ 118 #define UBLK_QID_OFF (UBLK_TAG_OFF + UBLK_TAG_BITS) 119 #define UBLK_QID_BITS 12 120 #define UBLK_QID_BITS_MASK ((1ULL << UBLK_QID_BITS) - 1) 121 122 #define UBLK_MAX_NR_QUEUES (1U << UBLK_QID_BITS) 123 124 #define UBLKSRV_IO_BUF_TOTAL_BITS (UBLK_QID_OFF + UBLK_QID_BITS) 125 #define UBLKSRV_IO_BUF_TOTAL_SIZE (1ULL << UBLKSRV_IO_BUF_TOTAL_BITS) 126 127 /* 128 * zero copy requires 4k block size, and can remap ublk driver's io 129 * request into ublksrv's vm space 130 */ 131 #define UBLK_F_SUPPORT_ZERO_COPY (1ULL << 0) 132 133 /* 134 * Force to complete io cmd via io_uring_cmd_complete_in_task so that 135 * performance comparison is done easily with using task_work_add 136 */ 137 #define UBLK_F_URING_CMD_COMP_IN_TASK (1ULL << 1) 138 139 /* 140 * User should issue io cmd again for write requests to 141 * set io buffer address and copy data from bio vectors 142 * to the userspace io buffer. 143 * 144 * In this mode, task_work is not used. 145 */ 146 #define UBLK_F_NEED_GET_DATA (1UL << 2) 147 148 #define UBLK_F_USER_RECOVERY (1UL << 3) 149 150 #define UBLK_F_USER_RECOVERY_REISSUE (1UL << 4) 151 152 /* 153 * Unprivileged user can create /dev/ublkcN and /dev/ublkbN. 154 * 155 * /dev/ublk-control needs to be available for unprivileged user, and it 156 * can be done via udev rule to make all control commands available to 157 * unprivileged user. Except for the command of UBLK_CMD_ADD_DEV, all 158 * other commands are only allowed for the owner of the specified device. 159 * 160 * When userspace sends UBLK_CMD_ADD_DEV, the device pair's owner_uid and 161 * owner_gid are stored to ublksrv_ctrl_dev_info by kernel, so far only 162 * the current user's uid/gid is stored, that said owner of the created 163 * device is always the current user. 164 * 165 * We still need udev rule to apply OWNER/GROUP with the stored owner_uid 166 * and owner_gid. 167 * 168 * Then ublk server can be run as unprivileged user, and /dev/ublkbN can 169 * be accessed and managed by its owner represented by owner_uid/owner_gid. 170 */ 171 #define UBLK_F_UNPRIVILEGED_DEV (1UL << 5) 172 173 /* use ioctl encoding for uring command */ 174 #define UBLK_F_CMD_IOCTL_ENCODE (1UL << 6) 175 176 /* Copy between request and user buffer by pread()/pwrite() */ 177 #define UBLK_F_USER_COPY (1UL << 7) 178 179 /* 180 * User space sets this flag when setting up the device to request zoned storage support. Kernel may 181 * deny the request by returning an error. 182 */ 183 #define UBLK_F_ZONED (1ULL << 8) 184 185 /* device state */ 186 #define UBLK_S_DEV_DEAD 0 187 #define UBLK_S_DEV_LIVE 1 188 #define UBLK_S_DEV_QUIESCED 2 189 190 /* shipped via sqe->cmd of io_uring command */ 191 struct ublksrv_ctrl_cmd { 192 /* sent to which device, must be valid */ 193 __u32 dev_id; 194 195 /* sent to which queue, must be -1 if the cmd isn't for queue */ 196 __u16 queue_id; 197 /* 198 * cmd specific buffer, can be IN or OUT. 199 */ 200 __u16 len; 201 __u64 addr; 202 203 /* __inline__ data */ 204 __u64 data[1]; 205 206 /* 207 * Used for UBLK_F_UNPRIVILEGED_DEV and UBLK_CMD_GET_DEV_INFO2 208 * only, include null char 209 */ 210 __u16 dev_path_len; 211 __u16 pad; 212 __u32 reserved; 213 }; 214 215 struct ublksrv_ctrl_dev_info { 216 __u16 nr_hw_queues; 217 __u16 queue_depth; 218 __u16 state; 219 __u16 pad0; 220 221 __u32 max_io_buf_bytes; 222 __u32 dev_id; 223 224 __s32 ublksrv_pid; 225 __u32 pad1; 226 227 __u64 flags; 228 229 /* For ublksrv internal use, invisible to ublk driver */ 230 __u64 ublksrv_flags; 231 232 __u32 owner_uid; /* store by kernel */ 233 __u32 owner_gid; /* store by kernel */ 234 __u64 reserved1; 235 __u64 reserved2; 236 }; 237 238 #define UBLK_IO_OP_READ 0 239 #define UBLK_IO_OP_WRITE 1 240 #define UBLK_IO_OP_FLUSH 2 241 #define UBLK_IO_OP_DISCARD 3 242 #define UBLK_IO_OP_WRITE_SAME 4 243 #define UBLK_IO_OP_WRITE_ZEROES 5 244 #define UBLK_IO_OP_ZONE_OPEN 10 245 #define UBLK_IO_OP_ZONE_CLOSE 11 246 #define UBLK_IO_OP_ZONE_FINISH 12 247 #define UBLK_IO_OP_ZONE_APPEND 13 248 #define UBLK_IO_OP_ZONE_RESET_ALL 14 249 #define UBLK_IO_OP_ZONE_RESET 15 250 /* 251 * Construct a zone report. The report request is carried in `struct 252 * ublksrv_io_desc`. The `start_sector` field must be the first sector of a zone 253 * and shall indicate the first zone of the report. The `nr_zones` shall 254 * indicate how many zones should be reported at most. The report shall be 255 * delivered as a `struct blk_zone` array. To report fewer zones than requested, 256 * zero the last entry of the returned array. 257 * 258 * Related definitions(blk_zone, blk_zone_cond, blk_zone_type, ...) in 259 * include/uapi/linux/blkzoned.h are part of ublk UAPI. 260 */ 261 #define UBLK_IO_OP_REPORT_ZONES 18 262 263 #define UBLK_IO_F_FAILFAST_DEV (1U << 8) 264 #define UBLK_IO_F_FAILFAST_TRANSPORT (1U << 9) 265 #define UBLK_IO_F_FAILFAST_DRIVER (1U << 10) 266 #define UBLK_IO_F_META (1U << 11) 267 #define UBLK_IO_F_FUA (1U << 13) 268 #define UBLK_IO_F_NOUNMAP (1U << 15) 269 #define UBLK_IO_F_SWAP (1U << 16) 270 271 /* 272 * io cmd is described by this structure, and stored in share memory, indexed 273 * by request tag. 274 * 275 * The data is stored by ublk driver, and read by ublksrv after one fetch command 276 * returns. 277 */ 278 struct ublksrv_io_desc { 279 /* op: bit 0-7, flags: bit 8-31 */ 280 __u32 op_flags; 281 282 union { 283 __u32 nr_sectors; 284 __u32 nr_zones; /* for UBLK_IO_OP_REPORT_ZONES */ 285 }; 286 287 /* start sector for this io */ 288 __u64 start_sector; 289 290 /* buffer address in ublksrv daemon vm space, from ublk driver */ 291 __u64 addr; 292 }; 293 294 static __inline__ __u8 ublksrv_get_op(const struct ublksrv_io_desc *iod) 295 { 296 return iod->op_flags & 0xff; 297 } 298 299 static __inline__ __u32 ublksrv_get_flags(const struct ublksrv_io_desc *iod) 300 { 301 return iod->op_flags >> 8; 302 } 303 304 /* issued to ublk driver via /dev/ublkcN */ 305 struct ublksrv_io_cmd { 306 __u16 q_id; 307 308 /* for fetch/commit which result */ 309 __u16 tag; 310 311 /* io result, it is valid for COMMIT* command only */ 312 __s32 result; 313 314 union { 315 /* 316 * userspace buffer address in ublksrv daemon process, valid for 317 * FETCH* command only 318 * 319 * `addr` should not be used when UBLK_F_USER_COPY is enabled, 320 * because userspace handles data copy by pread()/pwrite() over 321 * /dev/ublkcN. But in case of UBLK_F_ZONED, this union is 322 * re-used to pass back the allocated LBA for 323 * UBLK_IO_OP_ZONE_APPEND which actually depends on 324 * UBLK_F_USER_COPY 325 */ 326 __u64 addr; 327 __u64 zone_append_lba; 328 }; 329 }; 330 331 struct ublk_param_basic { 332 #define UBLK_ATTR_READ_ONLY (1 << 0) 333 #define UBLK_ATTR_ROTATIONAL (1 << 1) 334 #define UBLK_ATTR_VOLATILE_CACHE (1 << 2) 335 #define UBLK_ATTR_FUA (1 << 3) 336 __u32 attrs; 337 __u8 logical_bs_shift; 338 __u8 physical_bs_shift; 339 __u8 io_opt_shift; 340 __u8 io_min_shift; 341 342 __u32 max_sectors; 343 __u32 chunk_sectors; 344 345 __u64 dev_sectors; 346 __u64 virt_boundary_mask; 347 }; 348 349 struct ublk_param_discard { 350 __u32 discard_alignment; 351 352 __u32 discard_granularity; 353 __u32 max_discard_sectors; 354 355 __u32 max_write_zeroes_sectors; 356 __u16 max_discard_segments; 357 __u16 reserved0; 358 }; 359 360 /* 361 * read-only, can't set via UBLK_CMD_SET_PARAMS, disk_devt is available 362 * after device is started 363 */ 364 struct ublk_param_devt { 365 __u32 char_major; 366 __u32 char_minor; 367 __u32 disk_major; 368 __u32 disk_minor; 369 }; 370 371 struct ublk_param_zoned { 372 __u32 max_open_zones; 373 __u32 max_active_zones; 374 __u32 max_zone_append_sectors; 375 __u8 reserved[20]; 376 }; 377 378 struct ublk_params { 379 /* 380 * Total length of parameters, userspace has to set 'len' for both 381 * SET_PARAMS and GET_PARAMS command, and driver may update len 382 * if two sides use different version of 'ublk_params', same with 383 * 'types' fields. 384 */ 385 __u32 len; 386 #define UBLK_PARAM_TYPE_BASIC (1 << 0) 387 #define UBLK_PARAM_TYPE_DISCARD (1 << 1) 388 #define UBLK_PARAM_TYPE_DEVT (1 << 2) 389 #define UBLK_PARAM_TYPE_ZONED (1 << 3) 390 __u32 types; /* types of parameter included */ 391 392 struct ublk_param_basic basic; 393 struct ublk_param_discard discard; 394 struct ublk_param_devt devt; 395 struct ublk_param_zoned zoned; 396 }; 397 398 #endif
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