Commit bae818ee authored Oct 15, 2015 by Ronny Hegewald Committed by Ilya Dryomov Oct 30, 2015

rbd: require stable pages if message data CRCs are enabled



rbd requires stable pages, as it performs a crc of the page data before
they are send to the OSDs.

But since kernel 3.9 (patch 1d1d1a76
"mm: only enforce stable page writes if the backing device requires
it") it is not assumed anymore that block devices require stable pages.

This patch sets the necessary flag to get stable pages back for rbd.

In a ceph installation that provides multiple ext4 formatted rbd
devices "bad crc" messages appeared regularly (ca 1 message every 1-2
minutes on every OSD that provided the data for the rbd) in the
OSD-logs before this patch. After this patch this messages are pretty
much gone (only ca 1-2 / month / OSD).

Cc: stable@vger.kernel.org # 3.9+, needs backporting
Signed-off-by: Ronny Hegewald <Ronny.Hegewald@online.de>
[idryomov@gmail.com: require stable pages only in crc case, changelog]
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

parent 32b88194

drivers/block/rbd.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -3780,6 +3780,9 @@ static int rbd_init_disk(struct rbd_device *rbd_dev)
		blk_queue_max_discard_sectors(q, segment_size / SECTOR_SIZE);
		q->limits.discard_zeroes_data = 1;

		if (!ceph_test_opt(rbd_dev->rbd_client->client, NOCRC))
		q->backing_dev_info.capabilities \|= BDI_CAP_STABLE_WRITES;

		disk->queue = q;

		q->queuedata = rbd_dev;

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