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
5 #include <linux/types.h>
7 /* ublk server command definition */
10 * Admin commands, issued by ublk server, and handled by ublk driver.
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
22 * IO commands, issued by ublk server, and handled by ublk driver.
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
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.
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.
38 * It is only used if ublksrv set UBLK_F_NEED_GET_DATA flag
39 * while starting a ublk device.
41 #define UBLK_IO_FETCH_REQ 0x20
42 #define UBLK_IO_COMMIT_AND_FETCH_REQ 0x21
43 #define UBLK_IO_NEED_GET_DATA 0x22
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)
50 #define UBLKSRV_CMD_BUF_OFFSET 0
51 #define UBLKSRV_IO_BUF_OFFSET 0x80000000
53 /* tag bit is 12bit, so at most 4096 IOs for each queue */
54 #define UBLK_MAX_QUEUE_DEPTH 4096
57 * zero copy requires 4k block size, and can remap ublk driver's io
58 * request into ublksrv's vm space
60 #define UBLK_F_SUPPORT_ZERO_COPY (1ULL << 0)
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
66 #define UBLK_F_URING_CMD_COMP_IN_TASK (1ULL << 1)
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.
73 * In this mode, task_work is not used.
75 #define UBLK_F_NEED_GET_DATA (1UL << 2)
78 #define UBLK_S_DEV_DEAD 0
79 #define UBLK_S_DEV_LIVE 1
81 /* shipped via sqe->cmd of io_uring command */
82 struct ublksrv_ctrl_cmd {
83 /* sent to which device, must be valid */
86 /* sent to which queue, must be -1 if the cmd isn't for queue */
89 * cmd specific buffer, can be IN or OUT.
98 struct ublksrv_ctrl_dev_info {
104 __u32 max_io_buf_bytes;
112 /* For ublksrv internal use, invisible to ublk driver */
120 #define UBLK_IO_OP_READ 0
121 #define UBLK_IO_OP_WRITE 1
122 #define UBLK_IO_OP_FLUSH 2
123 #define UBLK_IO_OP_DISCARD 3
124 #define UBLK_IO_OP_WRITE_SAME 4
125 #define UBLK_IO_OP_WRITE_ZEROES 5
127 #define UBLK_IO_F_FAILFAST_DEV (1U << 8)
128 #define UBLK_IO_F_FAILFAST_TRANSPORT (1U << 9)
129 #define UBLK_IO_F_FAILFAST_DRIVER (1U << 10)
130 #define UBLK_IO_F_META (1U << 11)
131 #define UBLK_IO_F_FUA (1U << 13)
132 #define UBLK_IO_F_NOUNMAP (1U << 15)
133 #define UBLK_IO_F_SWAP (1U << 16)
136 * io cmd is described by this structure, and stored in share memory, indexed
139 * The data is stored by ublk driver, and read by ublksrv after one fetch command
142 struct ublksrv_io_desc {
143 /* op: bit 0-7, flags: bit 8-31 */
148 /* start sector for this io */
151 /* buffer address in ublksrv daemon vm space, from ublk driver */
155 static inline __u8 ublksrv_get_op(const struct ublksrv_io_desc *iod)
157 return iod->op_flags & 0xff;
160 static inline __u32 ublksrv_get_flags(const struct ublksrv_io_desc *iod)
162 return iod->op_flags >> 8;
165 /* issued to ublk driver via /dev/ublkcN */
166 struct ublksrv_io_cmd {
169 /* for fetch/commit which result */
172 /* io result, it is valid for COMMIT* command only */
176 * userspace buffer address in ublksrv daemon process, valid for
177 * FETCH* command only
182 struct ublk_param_basic {
183 #define UBLK_ATTR_READ_ONLY (1 << 0)
184 #define UBLK_ATTR_ROTATIONAL (1 << 1)
185 #define UBLK_ATTR_VOLATILE_CACHE (1 << 2)
186 #define UBLK_ATTR_FUA (1 << 3)
188 __u8 logical_bs_shift;
189 __u8 physical_bs_shift;
197 __u64 virt_boundary_mask;
200 struct ublk_param_discard {
201 __u32 discard_alignment;
203 __u32 discard_granularity;
204 __u32 max_discard_sectors;
206 __u32 max_write_zeroes_sectors;
207 __u16 max_discard_segments;
213 * Total length of parameters, userspace has to set 'len' for both
214 * SET_PARAMS and GET_PARAMS command, and driver may update len
215 * if two sides use different version of 'ublk_params', same with
219 #define UBLK_PARAM_TYPE_BASIC (1 << 0)
220 #define UBLK_PARAM_TYPE_DISCARD (1 << 1)
221 __u32 types; /* types of parameter included */
223 struct ublk_param_basic basic;
224 struct ublk_param_discard discard;