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
20 #define UBLK_CMD_START_USER_RECOVERY 0x10
21 #define UBLK_CMD_END_USER_RECOVERY 0x11
23 * IO commands, issued by ublk server, and handled by ublk driver.
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
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.
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.
39 * It is only used if ublksrv set UBLK_F_NEED_GET_DATA flag
40 * while starting a ublk device.
42 #define UBLK_IO_FETCH_REQ 0x20
43 #define UBLK_IO_COMMIT_AND_FETCH_REQ 0x21
44 #define UBLK_IO_NEED_GET_DATA 0x22
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)
51 #define UBLKSRV_CMD_BUF_OFFSET 0
52 #define UBLKSRV_IO_BUF_OFFSET 0x80000000
54 /* tag bit is 12bit, so at most 4096 IOs for each queue */
55 #define UBLK_MAX_QUEUE_DEPTH 4096
58 * zero copy requires 4k block size, and can remap ublk driver's io
59 * request into ublksrv's vm space
61 #define UBLK_F_SUPPORT_ZERO_COPY (1ULL << 0)
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
67 #define UBLK_F_URING_CMD_COMP_IN_TASK (1ULL << 1)
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.
74 * In this mode, task_work is not used.
76 #define UBLK_F_NEED_GET_DATA (1UL << 2)
78 #define UBLK_F_USER_RECOVERY (1UL << 3)
80 #define UBLK_F_USER_RECOVERY_REISSUE (1UL << 4)
83 #define UBLK_S_DEV_DEAD 0
84 #define UBLK_S_DEV_LIVE 1
85 #define UBLK_S_DEV_QUIESCED 2
87 /* shipped via sqe->cmd of io_uring command */
88 struct ublksrv_ctrl_cmd {
89 /* sent to which device, must be valid */
92 /* sent to which queue, must be -1 if the cmd isn't for queue */
95 * cmd specific buffer, can be IN or OUT.
104 struct ublksrv_ctrl_dev_info {
110 __u32 max_io_buf_bytes;
118 /* For ublksrv internal use, invisible to ublk driver */
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
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)
142 * io cmd is described by this structure, and stored in share memory, indexed
145 * The data is stored by ublk driver, and read by ublksrv after one fetch command
148 struct ublksrv_io_desc {
149 /* op: bit 0-7, flags: bit 8-31 */
154 /* start sector for this io */
157 /* buffer address in ublksrv daemon vm space, from ublk driver */
161 static inline __u8 ublksrv_get_op(const struct ublksrv_io_desc *iod)
163 return iod->op_flags & 0xff;
166 static inline __u32 ublksrv_get_flags(const struct ublksrv_io_desc *iod)
168 return iod->op_flags >> 8;
171 /* issued to ublk driver via /dev/ublkcN */
172 struct ublksrv_io_cmd {
175 /* for fetch/commit which result */
178 /* io result, it is valid for COMMIT* command only */
182 * userspace buffer address in ublksrv daemon process, valid for
183 * FETCH* command only
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)
194 __u8 logical_bs_shift;
195 __u8 physical_bs_shift;
203 __u64 virt_boundary_mask;
206 struct ublk_param_discard {
207 __u32 discard_alignment;
209 __u32 discard_granularity;
210 __u32 max_discard_sectors;
212 __u32 max_write_zeroes_sectors;
213 __u16 max_discard_segments;
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
225 #define UBLK_PARAM_TYPE_BASIC (1 << 0)
226 #define UBLK_PARAM_TYPE_DISCARD (1 << 1)
227 __u32 types; /* types of parameter included */
229 struct ublk_param_basic basic;
230 struct ublk_param_discard discard;