From: Stefan Weinhuber The DASD device driver never reorders the I/O requests and relies on the hardware to write all data to nonvolatile storage before signaling a successful write. Hence, the only thing we have to do to support write barriers is to set the queue ordered flag. Signed-off-by: Martin Schwidefsky Signed-off-by: Andrew Morton --- drivers/s390/block/dasd.c | 1 + 1 files changed, 1 insertion(+) diff -puN drivers/s390/block/dasd.c~s390-enable-write-barriers-in-the-dasd-driver drivers/s390/block/dasd.c --- 25/drivers/s390/block/dasd.c~s390-enable-write-barriers-in-the-dasd-driver 2005-04-26 03:41:14.902292832 -0700 +++ 25-akpm/drivers/s390/block/dasd.c 2005-04-26 03:41:14.906292224 -0700 @@ -1635,6 +1635,7 @@ dasd_setup_queue(struct dasd_device * de blk_queue_max_hw_segments(device->request_queue, -1L); blk_queue_max_segment_size(device->request_queue, -1L); blk_queue_segment_boundary(device->request_queue, -1L); + blk_queue_ordered(device->request_queue, 1); } /* _