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