DM_DEV_STATUS_CMD 1679 drivers/md/dm-ioctl.c 		{DM_DEV_STATUS_CMD, IOCTL_FLAGS_NO_PARAMS, dev_status},
DM_DEV_STATUS_CMD  259 include/uapi/linux/dm-ioctl.h #define DM_DEV_STATUS    _IOWR(DM_IOCTL, DM_DEV_STATUS_CMD, struct dm_ioctl)