2005-04-22 15:04:06

by Martin Schwidefsky

[permalink] [raw]
Subject: [patch 8/12] s390: enable write barriers in the dasd driver.

[patch 8/12] s390: enable write barriers in the dasd driver.

From: Stefan Weinhuber <[email protected]>

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 <[email protected]>

diffstat:
drivers/s390/block/dasd.c | 1 +
1 files changed, 1 insertion(+)

diff -urpN linux-2.6/drivers/s390/block/dasd.c linux-2.6-patched/drivers/s390/block/dasd.c
--- linux-2.6/drivers/s390/block/dasd.c 2005-04-22 15:45:04.000000000 +0200
+++ linux-2.6-patched/drivers/s390/block/dasd.c 2005-04-22 15:45:04.000000000 +0200
@@ -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);
}

/*