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1/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */2#ifndef USER_BLK_DRV_CMD_INC_H3#define USER_BLK_DRV_CMD_INC_H4 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't13 * add new such definition any more14 */15#define UBLK_CMD_GET_QUEUE_AFFINITY 0x0116#define UBLK_CMD_GET_DEV_INFO 0x0217#define UBLK_CMD_ADD_DEV 0x0418#define UBLK_CMD_DEL_DEV 0x0519#define UBLK_CMD_START_DEV 0x0620#define UBLK_CMD_STOP_DEV 0x0721#define UBLK_CMD_SET_PARAMS 0x0822#define UBLK_CMD_GET_PARAMS 0x0923#define UBLK_CMD_START_USER_RECOVERY 0x1024#define UBLK_CMD_END_USER_RECOVERY 0x1125#define UBLK_CMD_GET_DEV_INFO2 0x1226 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#define UBLK_U_CMD_DEL_DEV_ASYNC \53 _IOR('u', 0x14, struct ublksrv_ctrl_cmd)54 55/*56 * 64bits are enough now, and it should be easy to extend in case of57 * running out of feature flags58 */59#define UBLK_FEATURES_LEN 860 61/*62 * IO commands, issued by ublk server, and handled by ublk driver.63 *64 * FETCH_REQ: issued via sqe(URING_CMD) beforehand for fetching IO request65 * from ublk driver, should be issued only when starting device. After66 * the associated cqe is returned, request's tag can be retrieved via67 * cqe->userdata.68 *69 * COMMIT_AND_FETCH_REQ: issued via sqe(URING_CMD) after ublkserver handled70 * this IO request, request's handling result is committed to ublk71 * driver, meantime FETCH_REQ is piggyback, and FETCH_REQ has to be72 * handled before completing io request.73 *74 * NEED_GET_DATA: only used for write requests to set io addr and copy data75 * When NEED_GET_DATA is set, ublksrv has to issue UBLK_IO_NEED_GET_DATA76 * command after ublk driver returns UBLK_IO_RES_NEED_GET_DATA.77 *78 * It is only used if ublksrv set UBLK_F_NEED_GET_DATA flag79 * while starting a ublk device.80 */81 82/*83 * Legacy IO command definition, don't use in new application, and don't84 * add new such definition any more85 */86#define UBLK_IO_FETCH_REQ 0x2087#define UBLK_IO_COMMIT_AND_FETCH_REQ 0x2188#define UBLK_IO_NEED_GET_DATA 0x2289 90/* Any new IO command should encode by __IOWR() */91#define UBLK_U_IO_FETCH_REQ \92 _IOWR('u', UBLK_IO_FETCH_REQ, struct ublksrv_io_cmd)93#define UBLK_U_IO_COMMIT_AND_FETCH_REQ \94 _IOWR('u', UBLK_IO_COMMIT_AND_FETCH_REQ, struct ublksrv_io_cmd)95#define UBLK_U_IO_NEED_GET_DATA \96 _IOWR('u', UBLK_IO_NEED_GET_DATA, struct ublksrv_io_cmd)97 98/* only ABORT means that no re-fetch */99#define UBLK_IO_RES_OK 0100#define UBLK_IO_RES_NEED_GET_DATA 1101#define UBLK_IO_RES_ABORT (-ENODEV)102 103#define UBLKSRV_CMD_BUF_OFFSET 0104#define UBLKSRV_IO_BUF_OFFSET 0x80000000105 106/* tag bit is 16bit, so far limit at most 4096 IOs for each queue */107#define UBLK_MAX_QUEUE_DEPTH 4096108 109/* single IO buffer max size is 32MB */110#define UBLK_IO_BUF_OFF 0111#define UBLK_IO_BUF_BITS 25112#define UBLK_IO_BUF_BITS_MASK ((1ULL << UBLK_IO_BUF_BITS) - 1)113 114/* so at most 64K IOs for each queue */115#define UBLK_TAG_OFF UBLK_IO_BUF_BITS116#define UBLK_TAG_BITS 16117#define UBLK_TAG_BITS_MASK ((1ULL << UBLK_TAG_BITS) - 1)118 119/* max 4096 queues */120#define UBLK_QID_OFF (UBLK_TAG_OFF + UBLK_TAG_BITS)121#define UBLK_QID_BITS 12122#define UBLK_QID_BITS_MASK ((1ULL << UBLK_QID_BITS) - 1)123 124#define UBLK_MAX_NR_QUEUES (1U << UBLK_QID_BITS)125 126#define UBLKSRV_IO_BUF_TOTAL_BITS (UBLK_QID_OFF + UBLK_QID_BITS)127#define UBLKSRV_IO_BUF_TOTAL_SIZE (1ULL << UBLKSRV_IO_BUF_TOTAL_BITS)128 129/*130 * zero copy requires 4k block size, and can remap ublk driver's io131 * request into ublksrv's vm space132 */133#define UBLK_F_SUPPORT_ZERO_COPY (1ULL << 0)134 135/*136 * Force to complete io cmd via io_uring_cmd_complete_in_task so that137 * performance comparison is done easily with using task_work_add138 */139#define UBLK_F_URING_CMD_COMP_IN_TASK (1ULL << 1)140 141/*142 * User should issue io cmd again for write requests to143 * set io buffer address and copy data from bio vectors144 * to the userspace io buffer.145 *146 * In this mode, task_work is not used.147 */148#define UBLK_F_NEED_GET_DATA (1UL << 2)149 150#define UBLK_F_USER_RECOVERY (1UL << 3)151 152#define UBLK_F_USER_RECOVERY_REISSUE (1UL << 4)153 154/*155 * Unprivileged user can create /dev/ublkcN and /dev/ublkbN.156 *157 * /dev/ublk-control needs to be available for unprivileged user, and it158 * can be done via udev rule to make all control commands available to159 * unprivileged user. Except for the command of UBLK_CMD_ADD_DEV, all160 * other commands are only allowed for the owner of the specified device.161 *162 * When userspace sends UBLK_CMD_ADD_DEV, the device pair's owner_uid and163 * owner_gid are stored to ublksrv_ctrl_dev_info by kernel, so far only164 * the current user's uid/gid is stored, that said owner of the created165 * device is always the current user.166 *167 * We still need udev rule to apply OWNER/GROUP with the stored owner_uid168 * and owner_gid.169 *170 * Then ublk server can be run as unprivileged user, and /dev/ublkbN can171 * be accessed and managed by its owner represented by owner_uid/owner_gid.172 */173#define UBLK_F_UNPRIVILEGED_DEV (1UL << 5)174 175/* use ioctl encoding for uring command */176#define UBLK_F_CMD_IOCTL_ENCODE (1UL << 6)177 178/*179 * Copy between request and user buffer by pread()/pwrite()180 *181 * Not available for UBLK_F_UNPRIVILEGED_DEV, otherwise userspace may182 * deceive us by not filling request buffer, then kernel uninitialized183 * data may be leaked.184 */185#define UBLK_F_USER_COPY (1UL << 7)186 187/*188 * User space sets this flag when setting up the device to request zoned storage support. Kernel may189 * deny the request by returning an error.190 */191#define UBLK_F_ZONED (1ULL << 8)192 193/* device state */194#define UBLK_S_DEV_DEAD 0195#define UBLK_S_DEV_LIVE 1196#define UBLK_S_DEV_QUIESCED 2197 198/* shipped via sqe->cmd of io_uring command */199struct ublksrv_ctrl_cmd {200 /* sent to which device, must be valid */201 __u32 dev_id;202 203 /* sent to which queue, must be -1 if the cmd isn't for queue */204 __u16 queue_id;205 /*206 * cmd specific buffer, can be IN or OUT.207 */208 __u16 len;209 __u64 addr;210 211 /* inline data */212 __u64 data[1];213 214 /*215 * Used for UBLK_F_UNPRIVILEGED_DEV and UBLK_CMD_GET_DEV_INFO2216 * only, include null char217 */218 __u16 dev_path_len;219 __u16 pad;220 __u32 reserved;221};222 223struct ublksrv_ctrl_dev_info {224 __u16 nr_hw_queues;225 __u16 queue_depth;226 __u16 state;227 __u16 pad0;228 229 __u32 max_io_buf_bytes;230 __u32 dev_id;231 232 __s32 ublksrv_pid;233 __u32 pad1;234 235 __u64 flags;236 237 /* For ublksrv internal use, invisible to ublk driver */238 __u64 ublksrv_flags;239 240 __u32 owner_uid; /* store by kernel */241 __u32 owner_gid; /* store by kernel */242 __u64 reserved1;243 __u64 reserved2;244};245 246#define UBLK_IO_OP_READ 0247#define UBLK_IO_OP_WRITE 1248#define UBLK_IO_OP_FLUSH 2249#define UBLK_IO_OP_DISCARD 3250#define UBLK_IO_OP_WRITE_SAME 4251#define UBLK_IO_OP_WRITE_ZEROES 5252#define UBLK_IO_OP_ZONE_OPEN 10253#define UBLK_IO_OP_ZONE_CLOSE 11254#define UBLK_IO_OP_ZONE_FINISH 12255#define UBLK_IO_OP_ZONE_APPEND 13256#define UBLK_IO_OP_ZONE_RESET_ALL 14257#define UBLK_IO_OP_ZONE_RESET 15258/*259 * Construct a zone report. The report request is carried in `struct260 * ublksrv_io_desc`. The `start_sector` field must be the first sector of a zone261 * and shall indicate the first zone of the report. The `nr_zones` shall262 * indicate how many zones should be reported at most. The report shall be263 * delivered as a `struct blk_zone` array. To report fewer zones than requested,264 * zero the last entry of the returned array.265 *266 * Related definitions(blk_zone, blk_zone_cond, blk_zone_type, ...) in267 * include/uapi/linux/blkzoned.h are part of ublk UAPI.268 */269#define UBLK_IO_OP_REPORT_ZONES 18270 271#define UBLK_IO_F_FAILFAST_DEV (1U << 8)272#define UBLK_IO_F_FAILFAST_TRANSPORT (1U << 9)273#define UBLK_IO_F_FAILFAST_DRIVER (1U << 10)274#define UBLK_IO_F_META (1U << 11)275#define UBLK_IO_F_FUA (1U << 13)276#define UBLK_IO_F_NOUNMAP (1U << 15)277#define UBLK_IO_F_SWAP (1U << 16)278 279/*280 * io cmd is described by this structure, and stored in share memory, indexed281 * by request tag.282 *283 * The data is stored by ublk driver, and read by ublksrv after one fetch command284 * returns.285 */286struct ublksrv_io_desc {287 /* op: bit 0-7, flags: bit 8-31 */288 __u32 op_flags;289 290 union {291 __u32 nr_sectors;292 __u32 nr_zones; /* for UBLK_IO_OP_REPORT_ZONES */293 };294 295 /* start sector for this io */296 __u64 start_sector;297 298 /* buffer address in ublksrv daemon vm space, from ublk driver */299 __u64 addr;300};301 302static inline __u8 ublksrv_get_op(const struct ublksrv_io_desc *iod)303{304 return iod->op_flags & 0xff;305}306 307static inline __u32 ublksrv_get_flags(const struct ublksrv_io_desc *iod)308{309 return iod->op_flags >> 8;310}311 312/* issued to ublk driver via /dev/ublkcN */313struct ublksrv_io_cmd {314 __u16 q_id;315 316 /* for fetch/commit which result */317 __u16 tag;318 319 /* io result, it is valid for COMMIT* command only */320 __s32 result;321 322 union {323 /*324 * userspace buffer address in ublksrv daemon process, valid for325 * FETCH* command only326 *327 * `addr` should not be used when UBLK_F_USER_COPY is enabled,328 * because userspace handles data copy by pread()/pwrite() over329 * /dev/ublkcN. But in case of UBLK_F_ZONED, this union is330 * re-used to pass back the allocated LBA for331 * UBLK_IO_OP_ZONE_APPEND which actually depends on332 * UBLK_F_USER_COPY333 */334 __u64 addr;335 __u64 zone_append_lba;336 };337};338 339struct ublk_param_basic {340#define UBLK_ATTR_READ_ONLY (1 << 0)341#define UBLK_ATTR_ROTATIONAL (1 << 1)342#define UBLK_ATTR_VOLATILE_CACHE (1 << 2)343#define UBLK_ATTR_FUA (1 << 3)344 __u32 attrs;345 __u8 logical_bs_shift;346 __u8 physical_bs_shift;347 __u8 io_opt_shift;348 __u8 io_min_shift;349 350 __u32 max_sectors;351 __u32 chunk_sectors;352 353 __u64 dev_sectors;354 __u64 virt_boundary_mask;355};356 357struct ublk_param_discard {358 __u32 discard_alignment;359 360 __u32 discard_granularity;361 __u32 max_discard_sectors;362 363 __u32 max_write_zeroes_sectors;364 __u16 max_discard_segments;365 __u16 reserved0;366};367 368/*369 * read-only, can't set via UBLK_CMD_SET_PARAMS, disk_devt is available370 * after device is started371 */372struct ublk_param_devt {373 __u32 char_major;374 __u32 char_minor;375 __u32 disk_major;376 __u32 disk_minor;377};378 379struct ublk_param_zoned {380 __u32 max_open_zones;381 __u32 max_active_zones;382 __u32 max_zone_append_sectors;383 __u8 reserved[20];384};385 386struct ublk_params {387 /*388 * Total length of parameters, userspace has to set 'len' for both389 * SET_PARAMS and GET_PARAMS command, and driver may update len390 * if two sides use different version of 'ublk_params', same with391 * 'types' fields.392 */393 __u32 len;394#define UBLK_PARAM_TYPE_BASIC (1 << 0)395#define UBLK_PARAM_TYPE_DISCARD (1 << 1)396#define UBLK_PARAM_TYPE_DEVT (1 << 2)397#define UBLK_PARAM_TYPE_ZONED (1 << 3)398 __u32 types; /* types of parameter included */399 400 struct ublk_param_basic basic;401 struct ublk_param_discard discard;402 struct ublk_param_devt devt;403 struct ublk_param_zoned zoned;404};405 406#endif407