Commit 4e18403d authored by ZiyangZhang's avatar ZiyangZhang Committed by Jens Axboe
Browse files

ublk_cmd.h: add one new ublk command: UBLK_IO_NEED_GET_DATA 



Add one new ublk command: UBLK_IO_NEED_GET_DATA. It is prepared for a new
feature designed for a user application who wants to allocate IO buffer
and set IO buffer address only after it receives an IO request from
ublksrv.

Reviewed-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarZiyangZhang <ZiyangZhang@linux.alibaba.com>
Link: https://lore.kernel.org/r/c8a64b6b51c78340da7daa9e1054608695e79619.1659011443.git.ZiyangZhang@linux.alibaba.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 4bf9cbf3

include/uapi/linux/ublk_cmd.h

+18 −0
Original line number Diff line number Diff line
@@ -30,12 +30,21 @@ 
 *      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.

 *

 * NEED_GET_DATA: only used for write requests to set io addr and copy data

 *      When NEED_GET_DATA is set, ublksrv has to issue UBLK_IO_NEED_GET_DATA

 *      command after ublk driver returns UBLK_IO_RES_NEED_GET_DATA.

 *

 *      It is only used if ublksrv set UBLK_F_NEED_GET_DATA flag

 *      while starting a ublk device.

 */

#define	UBLK_IO_FETCH_REQ		0x20

#define	UBLK_IO_COMMIT_AND_FETCH_REQ	0x21

#define	UBLK_IO_NEED_GET_DATA	0x22



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

#define UBLK_IO_RES_OK			0

#define UBLK_IO_RES_NEED_GET_DATA	1

#define UBLK_IO_RES_ABORT		(-ENODEV)



#define UBLKSRV_CMD_BUF_OFFSET	0
@@ -56,6 +65,15 @@ 
 */

#define UBLK_F_URING_CMD_COMP_IN_TASK	(1ULL << 1)



/*

 * User should issue io cmd again for write requests to

 * set io buffer address and copy data from bio vectors

 * to the userspace io buffer.

 *

 * In this mode, task_work is not used.

 */

#define UBLK_F_NEED_GET_DATA (1UL << 2)



/* device state */

#define UBLK_S_DEV_DEAD	0

#define UBLK_S_DEV_LIVE	1