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 #define UBLK_CMD_GET_QUEUE_AFFINITY 0x01 13 #define UBLK_CMD_GET_DEV_INFO 0x02 14 #define UBLK_CMD_ADD_DEV 0x04 15 #define UBLK_CMD_DEL_DEV 0x05 16 #define UBLK_CMD_START_DEV 0x06 17 #define UBLK_CMD_STOP_DEV 0x07 18 #define UBLK_CMD_SET_PARAMS 0x08 19 #define UBLK_CMD_GET_PARAMS 0x09 20 #define UBLK_CMD_START_USER_RECOVERY 0x10 21 #define UBLK_CMD_END_USER_RECOVERY 0x11 22 /* 23 * IO commands, issued by ublk server, and handled by ublk driver. 24 * 25 * FETCH_REQ: issued via sqe(URING_CMD) beforehand for fetching IO request 26 * from ublk driver, should be issued only when starting device. After 27 * the associated cqe is returned, request's tag can be retrieved via 28 * cqe->userdata. 29 * 30 * COMMIT_AND_FETCH_REQ: issued via sqe(URING_CMD) after ublkserver handled 31 * this IO request, request's handling result is committed to ublk 32 * driver, meantime FETCH_REQ is piggyback, and FETCH_REQ has to be 33 * handled before completing io request. 34 * 35 * NEED_GET_DATA: only used for write requests to set io addr and copy data 36 * When NEED_GET_DATA is set, ublksrv has to issue UBLK_IO_NEED_GET_DATA 37 * command after ublk driver returns UBLK_IO_RES_NEED_GET_DATA. 38 * 39 * It is only used if ublksrv set UBLK_F_NEED_GET_DATA flag 40 * while starting a ublk device. 41 */ 42 #define UBLK_IO_FETCH_REQ 0x20 43 #define UBLK_IO_COMMIT_AND_FETCH_REQ 0x21 44 #define UBLK_IO_NEED_GET_DATA 0x22 45 46 /* only ABORT means that no re-fetch */ 47 #define UBLK_IO_RES_OK 0 48 #define UBLK_IO_RES_NEED_GET_DATA 1 49 #define UBLK_IO_RES_ABORT (-ENODEV) 50 51 #define UBLKSRV_CMD_BUF_OFFSET 0 52 #define UBLKSRV_IO_BUF_OFFSET 0x80000000 53 54 /* tag bit is 12bit, so at most 4096 IOs for each queue */ 55 #define UBLK_MAX_QUEUE_DEPTH 4096 56 57 /* 58 * zero copy requires 4k block size, and can remap ublk driver's io 59 * request into ublksrv's vm space 60 */ 61 #define UBLK_F_SUPPORT_ZERO_COPY (1ULL << 0) 62 63 /* 64 * Force to complete io cmd via io_uring_cmd_complete_in_task so that 65 * performance comparison is done easily with using task_work_add 66 */ 67 #define UBLK_F_URING_CMD_COMP_IN_TASK (1ULL << 1) 68 69 /* 70 * User should issue io cmd again for write requests to 71 * set io buffer address and copy data from bio vectors 72 * to the userspace io buffer. 73 * 74 * In this mode, task_work is not used. 75 */ 76 #define UBLK_F_NEED_GET_DATA (1UL << 2) 77 78 #define UBLK_F_USER_RECOVERY (1UL << 3) 79 80 #define UBLK_F_USER_RECOVERY_REISSUE (1UL << 4) 81 82 /* device state */ 83 #define UBLK_S_DEV_DEAD 0 84 #define UBLK_S_DEV_LIVE 1 85 #define UBLK_S_DEV_QUIESCED 2 86 87 /* shipped via sqe->cmd of io_uring command */ 88 struct ublksrv_ctrl_cmd { 89 /* sent to which device, must be valid */ 90 __u32 dev_id; 91 92 /* sent to which queue, must be -1 if the cmd isn't for queue */ 93 __u16 queue_id; 94 /* 95 * cmd specific buffer, can be IN or OUT. 96 */ 97 __u16 len; 98 __u64 addr; 99 100 /* inline data */ 101 __u64 data[2]; 102 }; 103 104 struct ublksrv_ctrl_dev_info { 105 __u16 nr_hw_queues; 106 __u16 queue_depth; 107 __u16 state; 108 __u16 pad0; 109 110 __u32 max_io_buf_bytes; 111 __u32 dev_id; 112 113 __s32 ublksrv_pid; 114 __u32 pad1; 115 116 __u64 flags; 117 118 /* For ublksrv internal use, invisible to ublk driver */ 119 __u64 ublksrv_flags; 120 121 __u64 reserved0; 122 __u64 reserved1; 123 __u64 reserved2; 124 }; 125 126 #define UBLK_IO_OP_READ 0 127 #define UBLK_IO_OP_WRITE 1 128 #define UBLK_IO_OP_FLUSH 2 129 #define UBLK_IO_OP_DISCARD 3 130 #define UBLK_IO_OP_WRITE_SAME 4 131 #define UBLK_IO_OP_WRITE_ZEROES 5 132 133 #define UBLK_IO_F_FAILFAST_DEV (1U << 8) 134 #define UBLK_IO_F_FAILFAST_TRANSPORT (1U << 9) 135 #define UBLK_IO_F_FAILFAST_DRIVER (1U << 10) 136 #define UBLK_IO_F_META (1U << 11) 137 #define UBLK_IO_F_FUA (1U << 13) 138 #define UBLK_IO_F_NOUNMAP (1U << 15) 139 #define UBLK_IO_F_SWAP (1U << 16) 140 141 /* 142 * io cmd is described by this structure, and stored in share memory, indexed 143 * by request tag. 144 * 145 * The data is stored by ublk driver, and read by ublksrv after one fetch command 146 * returns. 147 */ 148 struct ublksrv_io_desc { 149 /* op: bit 0-7, flags: bit 8-31 */ 150 __u32 op_flags; 151 152 __u32 nr_sectors; 153 154 /* start sector for this io */ 155 __u64 start_sector; 156 157 /* buffer address in ublksrv daemon vm space, from ublk driver */ 158 __u64 addr; 159 }; 160 161 static inline __u8 ublksrv_get_op(const struct ublksrv_io_desc *iod) 162 { 163 return iod->op_flags & 0xff; 164 } 165 166 static inline __u32 ublksrv_get_flags(const struct ublksrv_io_desc *iod) 167 { 168 return iod->op_flags >> 8; 169 } 170 171 /* issued to ublk driver via /dev/ublkcN */ 172 struct ublksrv_io_cmd { 173 __u16 q_id; 174 175 /* for fetch/commit which result */ 176 __u16 tag; 177 178 /* io result, it is valid for COMMIT* command only */ 179 __s32 result; 180 181 /* 182 * userspace buffer address in ublksrv daemon process, valid for 183 * FETCH* command only 184 */ 185 __u64 addr; 186 }; 187 188 struct ublk_param_basic { 189 #define UBLK_ATTR_READ_ONLY (1 << 0) 190 #define UBLK_ATTR_ROTATIONAL (1 << 1) 191 #define UBLK_ATTR_VOLATILE_CACHE (1 << 2) 192 #define UBLK_ATTR_FUA (1 << 3) 193 __u32 attrs; 194 __u8 logical_bs_shift; 195 __u8 physical_bs_shift; 196 __u8 io_opt_shift; 197 __u8 io_min_shift; 198 199 __u32 max_sectors; 200 __u32 chunk_sectors; 201 202 __u64 dev_sectors; 203 __u64 virt_boundary_mask; 204 }; 205 206 struct ublk_param_discard { 207 __u32 discard_alignment; 208 209 __u32 discard_granularity; 210 __u32 max_discard_sectors; 211 212 __u32 max_write_zeroes_sectors; 213 __u16 max_discard_segments; 214 __u16 reserved0; 215 }; 216 217 struct ublk_params { 218 /* 219 * Total length of parameters, userspace has to set 'len' for both 220 * SET_PARAMS and GET_PARAMS command, and driver may update len 221 * if two sides use different version of 'ublk_params', same with 222 * 'types' fields. 223 */ 224 __u32 len; 225 #define UBLK_PARAM_TYPE_BASIC (1 << 0) 226 #define UBLK_PARAM_TYPE_DISCARD (1 << 1) 227 __u32 types; /* types of parameter included */ 228 229 struct ublk_param_basic basic; 230 struct ublk_param_discard discard; 231 }; 232 233 #endif 234