[linux-block.git] / include / uapi / linux / ublk_cmd.h

/* 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 <linux/types.h>

/* ublk server command definition */

/*
 * Admin commands, issued by ublk server, and handled by ublk driver.
 */
#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

/*
 * 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.
 */
#define	UBLK_IO_FETCH_REQ		0x20
#define	UBLK_IO_COMMIT_AND_FETCH_REQ	0x21

/* only ABORT means that no re-fetch */
#define UBLK_IO_RES_OK			0
#define UBLK_IO_RES_ABORT		(-ENODEV)

#define UBLKSRV_CMD_BUF_OFFSET	0
#define UBLKSRV_IO_BUF_OFFSET	0x80000000

/* tag bit is 12bit, so at most 4096 IOs for each queue */
#define UBLK_MAX_QUEUE_DEPTH	4096

/*
 * 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	(1UL << 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	(1UL << 1)

/* device state */
#define UBLK_S_DEV_DEAD	0
#define UBLK_S_DEV_LIVE	1

/* 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[2];
};

struct ublksrv_ctrl_dev_info {
	__u16	nr_hw_queues;
	__u16	queue_depth;
	__u16	block_size;
	__u16	state;

	__u32	rq_max_blocks;
	__u32	dev_id;

	__u64   dev_blocks;

	__s32	ublksrv_pid;
	__s32	reserved0;
	__u64	flags[2];

	/* For ublksrv internal use, invisible to ublk driver */
	__u64	ublksrv_flags;
	__u64	reserved1[9];
};

#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_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;

	__u32		nr_sectors;

	/* 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;

	/*
	 * userspace buffer address in ublksrv daemon process, valid for
	 * FETCH* command only
	 */
	__u64	addr;
};

#endif
Commit	Line	Data
71f28f31 ML	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
	19	/*
	20	* IO commands, issued by ublk server, and handled by ublk driver.
	21	*
	22	* FETCH_REQ: issued via sqe(URING_CMD) beforehand for fetching IO request
	23	* from ublk driver, should be issued only when starting device. After
	24	* the associated cqe is returned, request's tag can be retrieved via
	25	* cqe->userdata.
	26	*
	27	* COMMIT_AND_FETCH_REQ: issued via sqe(URING_CMD) after ublkserver handled
	28	* this IO request, request's handling result is committed to ublk
	29	* driver, meantime FETCH_REQ is piggyback, and FETCH_REQ has to be
	30	* handled before completing io request.
	31	*/
	32	#define UBLK_IO_FETCH_REQ 0x20
	33	#define UBLK_IO_COMMIT_AND_FETCH_REQ 0x21
	34
	35	/* only ABORT means that no re-fetch */
	36	#define UBLK_IO_RES_OK 0
	37	#define UBLK_IO_RES_ABORT (-ENODEV)
	38
	39	#define UBLKSRV_CMD_BUF_OFFSET 0
	40	#define UBLKSRV_IO_BUF_OFFSET 0x80000000
	41
	42	/* tag bit is 12bit, so at most 4096 IOs for each queue */
	43	#define UBLK_MAX_QUEUE_DEPTH 4096
	44
	45	/*
	46	* zero copy requires 4k block size, and can remap ublk driver's io
	47	* request into ublksrv's vm space
	48	*/
	49	#define UBLK_F_SUPPORT_ZERO_COPY (1UL << 0)
	50
0edb3696 ML	51	/*
	52	* Force to complete io cmd via io_uring_cmd_complete_in_task so that
	53	* performance comparison is done easily with using task_work_add
	54	*/
	55	#define UBLK_F_URING_CMD_COMP_IN_TASK (1UL << 1)
	56
71f28f31 ML	57	/* device state */
	58	#define UBLK_S_DEV_DEAD 0
	59	#define UBLK_S_DEV_LIVE 1
	60
	61	/* shipped via sqe->cmd of io_uring command */
	62	struct ublksrv_ctrl_cmd {
	63	/* sent to which device, must be valid */
	64	__u32 dev_id;
	65
	66	/* sent to which queue, must be -1 if the cmd isn't for queue */
	67	__u16 queue_id;
	68	/*
	69	* cmd specific buffer, can be IN or OUT.
	70	*/
	71	__u16 len;
	72	__u64 addr;
	73
	74	/* inline data */
	75	__u64 data[2];
	76	};
	77
	78	struct ublksrv_ctrl_dev_info {
	79	__u16 nr_hw_queues;
	80	__u16 queue_depth;
	81	__u16 block_size;
	82	__u16 state;
	83
	84	__u32 rq_max_blocks;
	85	__u32 dev_id;
	86
	87	__u64 dev_blocks;
	88
	89	__s32 ublksrv_pid;
	90	__s32 reserved0;
	91	__u64 flags[2];
	92
	93	/* For ublksrv internal use, invisible to ublk driver */
	94	__u64 ublksrv_flags;
	95	__u64 reserved1[9];
	96	};
	97
	98	#define UBLK_IO_OP_READ 0
	99	#define UBLK_IO_OP_WRITE 1
	100	#define UBLK_IO_OP_FLUSH 2
	101	#define UBLK_IO_OP_DISCARD 3
	102	#define UBLK_IO_OP_WRITE_SAME 4
	103	#define UBLK_IO_OP_WRITE_ZEROES 5
	104
	105	#define UBLK_IO_F_FAILFAST_DEV (1U << 8)
	106	#define UBLK_IO_F_FAILFAST_TRANSPORT (1U << 9)
	107	#define UBLK_IO_F_FAILFAST_DRIVER (1U << 10)
	108	#define UBLK_IO_F_META (1U << 11)
71f28f31	109	#define UBLK_IO_F_FUA (1U << 13)
71f28f31 ML	110	#define UBLK_IO_F_NOUNMAP (1U << 15)
	111	#define UBLK_IO_F_SWAP (1U << 16)
	112
	113	/*
	114	* io cmd is described by this structure, and stored in share memory, indexed
	115	* by request tag.
	116	*
	117	* The data is stored by ublk driver, and read by ublksrv after one fetch command
	118	* returns.
	119	*/
	120	struct ublksrv_io_desc {
	121	/* op: bit 0-7, flags: bit 8-31 */
	122	__u32 op_flags;
	123
	124	__u32 nr_sectors;
	125
	126	/* start sector for this io */
	127	__u64 start_sector;
	128
	129	/* buffer address in ublksrv daemon vm space, from ublk driver */
	130	__u64 addr;
	131	};
	132
	133	static inline __u8 ublksrv_get_op(const struct ublksrv_io_desc *iod)
	134	{
	135	return iod->op_flags & 0xff;
	136	}
	137
	138	static inline __u32 ublksrv_get_flags(const struct ublksrv_io_desc *iod)
	139	{
	140	return iod->op_flags >> 8;
	141	}
	142
	143	/* issued to ublk driver via /dev/ublkcN */
	144	struct ublksrv_io_cmd {
	145	__u16 q_id;
	146
	147	/* for fetch/commit which result */
	148	__u16 tag;
	149
	150	/* io result, it is valid for COMMIT* command only */
	151	__s32 result;
	152
	153	/*
	154	* userspace buffer address in ublksrv daemon process, valid for
	155	* FETCH* command only
	156	*/
	157	__u64 addr;
	158	};
	159
	160	#endif