/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ #ifndef USER_BLK_DRV_CMD_INC_H #define USER_BLK_DRV_CMD_INC_H #include /* ublk server command definition */ /* * Admin commands, issued by ublk server, and handled by ublk driver. * * Legacy command definition, don't use in new application, and don't * add new such definition any more */ #define UBLK_CMD_GET_QUEUE_AFFINITY 0x01 #define UBLK_CMD_GET_DEV_INFO 0x02 #define UBLK_CMD_ADD_DEV 0x04 #define UBLK_CMD_DEL_DEV 0x05 #define UBLK_CMD_START_DEV 0x06 #define UBLK_CMD_STOP_DEV 0x07 #define UBLK_CMD_SET_PARAMS 0x08 #define UBLK_CMD_GET_PARAMS 0x09 #define UBLK_CMD_START_USER_RECOVERY 0x10 #define UBLK_CMD_END_USER_RECOVERY 0x11 #define UBLK_CMD_GET_DEV_INFO2 0x12 /* Any new ctrl command should encode by __IO*() */ #define UBLK_U_CMD_GET_QUEUE_AFFINITY \ _IOR('u', UBLK_CMD_GET_QUEUE_AFFINITY, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_GET_DEV_INFO \ _IOR('u', UBLK_CMD_GET_DEV_INFO, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_ADD_DEV \ _IOWR('u', UBLK_CMD_ADD_DEV, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_DEL_DEV \ _IOWR('u', UBLK_CMD_DEL_DEV, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_START_DEV \ _IOWR('u', UBLK_CMD_START_DEV, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_STOP_DEV \ _IOWR('u', UBLK_CMD_STOP_DEV, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_SET_PARAMS \ _IOWR('u', UBLK_CMD_SET_PARAMS, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_GET_PARAMS \ _IOR('u', UBLK_CMD_GET_PARAMS, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_START_USER_RECOVERY \ _IOWR('u', UBLK_CMD_START_USER_RECOVERY, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_END_USER_RECOVERY \ _IOWR('u', UBLK_CMD_END_USER_RECOVERY, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_GET_DEV_INFO2 \ _IOR('u', UBLK_CMD_GET_DEV_INFO2, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_GET_FEATURES \ _IOR('u', 0x13, struct ublksrv_ctrl_cmd) #define UBLK_U_CMD_DEL_DEV_ASYNC \ _IOR('u', 0x14, struct ublksrv_ctrl_cmd) /* * 64bits are enough now, and it should be easy to extend in case of * running out of feature flags */ #define UBLK_FEATURES_LEN 8 /* * IO commands, issued by ublk server, and handled by ublk driver. * * FETCH_REQ: issued via sqe(URING_CMD) beforehand for fetching IO request * from ublk driver, should be issued only when starting device. After * the associated cqe is returned, request's tag can be retrieved via * cqe->userdata. * * COMMIT_AND_FETCH_REQ: issued via sqe(URING_CMD) after ublkserver handled * this IO request, request's handling result is committed to ublk * driver, meantime FETCH_REQ is piggyback, and FETCH_REQ has to be * handled before completing io request. * * NEED_GET_DATA: only used for write requests to set io addr and copy data * When NEED_GET_DATA is set, ublksrv has to issue UBLK_IO_NEED_GET_DATA * command after ublk driver returns UBLK_IO_RES_NEED_GET_DATA. * * It is only used if ublksrv set UBLK_F_NEED_GET_DATA flag * while starting a ublk device. */ /* * Legacy IO command definition, don't use in new application, and don't * add new such definition any more */ #define UBLK_IO_FETCH_REQ 0x20 #define UBLK_IO_COMMIT_AND_FETCH_REQ 0x21 #define UBLK_IO_NEED_GET_DATA 0x22 /* Any new IO command should encode by __IOWR() */ #define UBLK_U_IO_FETCH_REQ \ _IOWR('u', UBLK_IO_FETCH_REQ, struct ublksrv_io_cmd) #define UBLK_U_IO_COMMIT_AND_FETCH_REQ \ _IOWR('u', UBLK_IO_COMMIT_AND_FETCH_REQ, struct ublksrv_io_cmd) #define UBLK_U_IO_NEED_GET_DATA \ _IOWR('u', UBLK_IO_NEED_GET_DATA, struct ublksrv_io_cmd) /* only ABORT means that no re-fetch */ #define UBLK_IO_RES_OK 0 #define UBLK_IO_RES_NEED_GET_DATA 1 #define UBLK_IO_RES_ABORT (-ENODEV) #define UBLKSRV_CMD_BUF_OFFSET 0 #define UBLKSRV_IO_BUF_OFFSET 0x80000000 /* tag bit is 16bit, so far limit at most 4096 IOs for each queue */ #define UBLK_MAX_QUEUE_DEPTH 4096 /* single IO buffer max size is 32MB */ #define UBLK_IO_BUF_OFF 0 #define UBLK_IO_BUF_BITS 25 #define UBLK_IO_BUF_BITS_MASK ((1ULL << UBLK_IO_BUF_BITS) - 1) /* so at most 64K IOs for each queue */ #define UBLK_TAG_OFF UBLK_IO_BUF_BITS #define UBLK_TAG_BITS 16 #define UBLK_TAG_BITS_MASK ((1ULL << UBLK_TAG_BITS) - 1) /* max 4096 queues */ #define UBLK_QID_OFF (UBLK_TAG_OFF + UBLK_TAG_BITS) #define UBLK_QID_BITS 12 #define UBLK_QID_BITS_MASK ((1ULL << UBLK_QID_BITS) - 1) #define UBLK_MAX_NR_QUEUES (1U << UBLK_QID_BITS) #define UBLKSRV_IO_BUF_TOTAL_BITS (UBLK_QID_OFF + UBLK_QID_BITS) #define UBLKSRV_IO_BUF_TOTAL_SIZE (1ULL << UBLKSRV_IO_BUF_TOTAL_BITS) /* * zero copy requires 4k block size, and can remap ublk driver's io * request into ublksrv's vm space */ #define UBLK_F_SUPPORT_ZERO_COPY (1ULL << 0) /* * Force to complete io cmd via io_uring_cmd_complete_in_task so that * performance comparison is done easily with using task_work_add */ #define UBLK_F_URING_CMD_COMP_IN_TASK (1ULL << 1) /* * User should issue io cmd again for write requests to * set io buffer address and copy data from bio vectors * to the userspace io buffer. * * In this mode, task_work is not used. */ #define UBLK_F_NEED_GET_DATA (1UL << 2) #define UBLK_F_USER_RECOVERY (1UL << 3) #define UBLK_F_USER_RECOVERY_REISSUE (1UL << 4) /* * Unprivileged user can create /dev/ublkcN and /dev/ublkbN. * * /dev/ublk-control needs to be available for unprivileged user, and it * can be done via udev rule to make all control commands available to * unprivileged user. Except for the command of UBLK_CMD_ADD_DEV, all * other commands are only allowed for the owner of the specified device. * * When userspace sends UBLK_CMD_ADD_DEV, the device pair's owner_uid and * owner_gid are stored to ublksrv_ctrl_dev_info by kernel, so far only * the current user's uid/gid is stored, that said owner of the created * device is always the current user. * * We still need udev rule to apply OWNER/GROUP with the stored owner_uid * and owner_gid. * * Then ublk server can be run as unprivileged user, and /dev/ublkbN can * be accessed and managed by its owner represented by owner_uid/owner_gid. */ #define UBLK_F_UNPRIVILEGED_DEV (1UL << 5) /* use ioctl encoding for uring command */ #define UBLK_F_CMD_IOCTL_ENCODE (1UL << 6) /* Copy between request and user buffer by pread()/pwrite() */ #define UBLK_F_USER_COPY (1UL << 7) /* * User space sets this flag when setting up the device to request zoned storage support. Kernel may * deny the request by returning an error. */ #define UBLK_F_ZONED (1ULL << 8) /* device state */ #define UBLK_S_DEV_DEAD 0 #define UBLK_S_DEV_LIVE 1 #define UBLK_S_DEV_QUIESCED 2 /* shipped via sqe->cmd of io_uring command */ struct ublksrv_ctrl_cmd { /* sent to which device, must be valid */ __u32 dev_id; /* sent to which queue, must be -1 if the cmd isn't for queue */ __u16 queue_id; /* * cmd specific buffer, can be IN or OUT. */ __u16 len; __u64 addr; /* inline data */ __u64 data[1]; /* * Used for UBLK_F_UNPRIVILEGED_DEV and UBLK_CMD_GET_DEV_INFO2 * only, include null char */ __u16 dev_path_len; __u16 pad; __u32 reserved; }; struct ublksrv_ctrl_dev_info { __u16 nr_hw_queues; __u16 queue_depth; __u16 state; __u16 pad0; __u32 max_io_buf_bytes; __u32 dev_id; __s32 ublksrv_pid; __u32 pad1; __u64 flags; /* For ublksrv internal use, invisible to ublk driver */ __u64 ublksrv_flags; __u32 owner_uid; /* store by kernel */ __u32 owner_gid; /* store by kernel */ __u64 reserved1; __u64 reserved2; }; #define UBLK_IO_OP_READ 0 #define UBLK_IO_OP_WRITE 1 #define UBLK_IO_OP_FLUSH 2 #define UBLK_IO_OP_DISCARD 3 #define UBLK_IO_OP_WRITE_SAME 4 #define UBLK_IO_OP_WRITE_ZEROES 5 #define UBLK_IO_OP_ZONE_OPEN 10 #define UBLK_IO_OP_ZONE_CLOSE 11 #define UBLK_IO_OP_ZONE_FINISH 12 #define UBLK_IO_OP_ZONE_APPEND 13 #define UBLK_IO_OP_ZONE_RESET_ALL 14 #define UBLK_IO_OP_ZONE_RESET 15 /* * Construct a zone report. The report request is carried in `struct * ublksrv_io_desc`. The `start_sector` field must be the first sector of a zone * and shall indicate the first zone of the report. The `nr_zones` shall * indicate how many zones should be reported at most. The report shall be * delivered as a `struct blk_zone` array. To report fewer zones than requested, * zero the last entry of the returned array. * * Related definitions(blk_zone, blk_zone_cond, blk_zone_type, ...) in * include/uapi/linux/blkzoned.h are part of ublk UAPI. */ #define UBLK_IO_OP_REPORT_ZONES 18 #define UBLK_IO_F_FAILFAST_DEV (1U << 8) #define UBLK_IO_F_FAILFAST_TRANSPORT (1U << 9) #define UBLK_IO_F_FAILFAST_DRIVER (1U << 10) #define UBLK_IO_F_META (1U << 11) #define UBLK_IO_F_FUA (1U << 13) #define UBLK_IO_F_NOUNMAP (1U << 15) #define UBLK_IO_F_SWAP (1U << 16) /* * io cmd is described by this structure, and stored in share memory, indexed * by request tag. * * The data is stored by ublk driver, and read by ublksrv after one fetch command * returns. */ struct ublksrv_io_desc { /* op: bit 0-7, flags: bit 8-31 */ __u32 op_flags; /* bindgen can't handle union well */ #if 0 union { __u32 nr_sectors; __u32 nr_zones; /* for UBLK_IO_OP_REPORT_ZONES */ }; #else __u32 nr_sectors; #endif /* start sector for this io */ __u64 start_sector; /* buffer address in ublksrv daemon vm space, from ublk driver */ __u64 addr; }; static inline __u8 ublksrv_get_op(const struct ublksrv_io_desc *iod) { return iod->op_flags & 0xff; } static inline __u32 ublksrv_get_flags(const struct ublksrv_io_desc *iod) { return iod->op_flags >> 8; } /* issued to ublk driver via /dev/ublkcN */ struct ublksrv_io_cmd { __u16 q_id; /* for fetch/commit which result */ __u16 tag; /* io result, it is valid for COMMIT* command only */ __s32 result; #if 0 union { /* * userspace buffer address in ublksrv daemon process, valid for * FETCH* command only * * `addr` should not be used when UBLK_F_USER_COPY is enabled, * because userspace handles data copy by pread()/pwrite() over * /dev/ublkcN. But in case of UBLK_F_ZONED, this union is * re-used to pass back the allocated LBA for * UBLK_IO_OP_ZONE_APPEND which actually depends on * UBLK_F_USER_COPY */ __u64 addr; __u64 zone_append_lba; }; #else __u64 addr; #endif }; struct ublk_param_basic { #define UBLK_ATTR_READ_ONLY (1 << 0) #define UBLK_ATTR_ROTATIONAL (1 << 1) #define UBLK_ATTR_VOLATILE_CACHE (1 << 2) #define UBLK_ATTR_FUA (1 << 3) __u32 attrs; __u8 logical_bs_shift; __u8 physical_bs_shift; __u8 io_opt_shift; __u8 io_min_shift; __u32 max_sectors; __u32 chunk_sectors; __u64 dev_sectors; __u64 virt_boundary_mask; }; struct ublk_param_discard { __u32 discard_alignment; __u32 discard_granularity; __u32 max_discard_sectors; __u32 max_write_zeroes_sectors; __u16 max_discard_segments; __u16 reserved0; }; /* * read-only, can't set via UBLK_CMD_SET_PARAMS, disk_devt is available * after device is started */ struct ublk_param_devt { __u32 char_major; __u32 char_minor; __u32 disk_major; __u32 disk_minor; }; struct ublk_param_zoned { __u32 max_open_zones; __u32 max_active_zones; __u32 max_zone_append_sectors; __u8 reserved[20]; }; struct ublk_params { /* * Total length of parameters, userspace has to set 'len' for both * SET_PARAMS and GET_PARAMS command, and driver may update len * if two sides use different version of 'ublk_params', same with * 'types' fields. */ __u32 len; #define UBLK_PARAM_TYPE_BASIC (1 << 0) #define UBLK_PARAM_TYPE_DISCARD (1 << 1) #define UBLK_PARAM_TYPE_DEVT (1 << 2) #define UBLK_PARAM_TYPE_ZONED (1 << 3) __u32 types; /* types of parameter included */ struct ublk_param_basic basic; struct ublk_param_discard discard; struct ublk_param_devt devt; struct ublk_param_zoned zoned; }; #endif