Commit e86f89ab authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

ublk: add new batch command UBLK_U_IO_PREP_IO_CMDS & UBLK_U_IO_COMMIT_IO_CMDS 



Add new command UBLK_U_IO_PREP_IO_CMDS, which is the batch version of
UBLK_IO_FETCH_REQ.

Add new command UBLK_U_IO_COMMIT_IO_CMDS, which is for committing io command
result only, still the batch version.

The new command header type is `struct ublk_batch_io`.

This patch doesn't actually implement these commands yet, just validates the
SQE fields.

Reviewed-by: default avatarCaleb Sander Mateos <csander@purestorage.com>
Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 7ba62f59

drivers/block/ublk_drv.c

+86 −1
Original line number Diff line number Diff line
@@ -91,6 +91,11 @@ 
	 UBLK_PARAM_TYPE_DMA_ALIGN | UBLK_PARAM_TYPE_SEGMENT | \

	 UBLK_PARAM_TYPE_INTEGRITY)



#define UBLK_BATCH_F_ALL  \

	(UBLK_BATCH_F_HAS_ZONE_LBA | \

	 UBLK_BATCH_F_HAS_BUF_ADDR | \

	 UBLK_BATCH_F_AUTO_BUF_REG_FALLBACK)



struct ublk_uring_cmd_pdu {

	/*

	 * Store requests in same batch temporarily for queuing them to
@@ -114,6 +119,13 @@ struct ublk_uring_cmd_pdu { 
	u16 tag;

};



struct ublk_batch_io_data {

	struct ublk_device *ub;

	struct io_uring_cmd *cmd;

	struct ublk_batch_io header;

	unsigned int issue_flags;

};



/*

 * io command is active: sqe cmd is received, and its cqe isn't done

 *
@@ -2687,10 +2699,83 @@ static int ublk_ch_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) 
	return ublk_ch_uring_cmd_local(cmd, issue_flags);

}



static int ublk_check_batch_cmd_flags(const struct ublk_batch_io *uc)

{

	unsigned elem_bytes = sizeof(struct ublk_elem_header);



	if (uc->flags & ~UBLK_BATCH_F_ALL)

		return -EINVAL;



	/* UBLK_BATCH_F_AUTO_BUF_REG_FALLBACK requires buffer index */

	if ((uc->flags & UBLK_BATCH_F_AUTO_BUF_REG_FALLBACK) &&

			(uc->flags & UBLK_BATCH_F_HAS_BUF_ADDR))

		return -EINVAL;



	elem_bytes += (uc->flags & UBLK_BATCH_F_HAS_ZONE_LBA ? sizeof(u64) : 0) +

		(uc->flags & UBLK_BATCH_F_HAS_BUF_ADDR ? sizeof(u64) : 0);

	if (uc->elem_bytes != elem_bytes)

		return -EINVAL;

	return 0;

}



static int ublk_check_batch_cmd(const struct ublk_batch_io_data *data)

{



	const struct ublk_batch_io *uc = &data->header;



	if (uc->nr_elem > data->ub->dev_info.queue_depth)

		return -E2BIG;



	if ((uc->flags & UBLK_BATCH_F_HAS_ZONE_LBA) &&

			!ublk_dev_is_zoned(data->ub))

		return -EINVAL;



	if ((uc->flags & UBLK_BATCH_F_HAS_BUF_ADDR) &&

			!ublk_dev_need_map_io(data->ub))

		return -EINVAL;



	if ((uc->flags & UBLK_BATCH_F_AUTO_BUF_REG_FALLBACK) &&

			!ublk_dev_support_auto_buf_reg(data->ub))

		return -EINVAL;



	return ublk_check_batch_cmd_flags(uc);

}



static int ublk_ch_batch_io_uring_cmd(struct io_uring_cmd *cmd,

				       unsigned int issue_flags)

{

	return -EOPNOTSUPP;

	const struct ublk_batch_io *uc = io_uring_sqe_cmd(cmd->sqe);

	struct ublk_device *ub = cmd->file->private_data;

	struct ublk_batch_io_data data = {

		.ub  = ub,

		.cmd = cmd,

		.header = (struct ublk_batch_io) {

			.q_id = READ_ONCE(uc->q_id),

			.flags = READ_ONCE(uc->flags),

			.nr_elem = READ_ONCE(uc->nr_elem),

			.elem_bytes = READ_ONCE(uc->elem_bytes),

		},

		.issue_flags = issue_flags,

	};

	u32 cmd_op = cmd->cmd_op;

	int ret = -EINVAL;



	if (data.header.q_id >= ub->dev_info.nr_hw_queues)

		goto out;



	switch (cmd_op) {

	case UBLK_U_IO_PREP_IO_CMDS:

	case UBLK_U_IO_COMMIT_IO_CMDS:

		ret = ublk_check_batch_cmd(&data);

		if (ret)

			goto out;

		ret = -EOPNOTSUPP;

		break;

	default:

		ret = -EOPNOTSUPP;

	}

out:

	return ret;

}



static inline bool ublk_check_ubuf_dir(const struct request *req,

include/uapi/linux/ublk_cmd.h

+49 −0
Original line number Diff line number Diff line
@@ -103,6 +103,10 @@ 
	_IOWR('u', 0x23, struct ublksrv_io_cmd)

#define	UBLK_U_IO_UNREGISTER_IO_BUF	\

	_IOWR('u', 0x24, struct ublksrv_io_cmd)

#define	UBLK_U_IO_PREP_IO_CMDS	\

	_IOWR('u', 0x25, struct ublk_batch_io)

#define	UBLK_U_IO_COMMIT_IO_CMDS	\

	_IOWR('u', 0x26, struct ublk_batch_io)



/* only ABORT means that no re-fetch */

#define UBLK_IO_RES_OK			0
@@ -544,6 +548,51 @@ struct ublksrv_io_cmd { 
	};

};



struct ublk_elem_header {

	__u16 tag;	/* IO tag */



	/*

	 * Buffer index for incoming io command, only valid iff

	 * UBLK_F_AUTO_BUF_REG is set

	 */

	__u16 buf_index;

	__s32 result;	/* I/O completion result (commit only) */

};



/*

 * uring_cmd buffer structure for batch commands

 *

 * buffer includes multiple elements, which number is specified by

 * `nr_elem`. Each element buffer is organized in the following order:

 *

 * struct ublk_elem_buffer {

 * 	// Mandatory fields (8 bytes)

 * 	struct ublk_elem_header header;

 *

 * 	// Optional fields (8 bytes each, included based on flags)

 *

 * 	// Buffer address (if UBLK_BATCH_F_HAS_BUF_ADDR) for copying data

 * 	// between ublk request and ublk server buffer

 * 	__u64 buf_addr;

 *

 * 	// returned Zone append LBA (if UBLK_BATCH_F_HAS_ZONE_LBA)

 * 	__u64 zone_lba;

 * }

 *

 * Used for `UBLK_U_IO_PREP_IO_CMDS` and `UBLK_U_IO_COMMIT_IO_CMDS`

 */

struct ublk_batch_io {

	__u16  q_id;

#define UBLK_BATCH_F_HAS_ZONE_LBA	(1 << 0)

#define UBLK_BATCH_F_HAS_BUF_ADDR 	(1 << 1)

#define UBLK_BATCH_F_AUTO_BUF_REG_FALLBACK	(1 << 2)

	__u16	flags;

	__u16	nr_elem;

	__u8	elem_bytes;

	__u8	reserved;

	__u64   reserved2;

};



struct ublk_param_basic {

#define UBLK_ATTR_READ_ONLY            (1 << 0)

#define UBLK_ATTR_ROTATIONAL           (1 << 1)