Commit 86e1e98e authored Jun 28, 2011 by Lars Ellenberg Committed by Philipp Reisner Jun 30, 2011

drbd: we should write meta data updates with FLUSH FUA



We used to write these with BIO_RW_BARRIER aka REQ_HARDBARRIER (unless
disabled in the configuration). The correct semantic now would be to
write with FLUSH/FUA.
For example, with activity log transactions, FUA alone is not enough, we
need the corresponding bitmap update (and all related application
updates) on stable storage as well.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>

parent 15b493d1

drivers/block/drbd/drbd_actlog.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -79,7 +79,7 @@ static int _drbd_md_sync_page_io(struct drbd_conf *mdev,
		md_io.error = 0;

		if ((rw & WRITE) && !test_bit(MD_NO_FUA, &mdev->flags))
		rw \|= REQ_FUA;
		rw \|= REQ_FUA \| REQ_FLUSH;
		rw \|= REQ_SYNC;

		bio = bio_alloc(GFP_NOIO, 1);