Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client

Pull Ceph fix from Sage Weil:
 "This sets the stable pages flag on the RBD block device when we have
  CRCs enabled.  (This is necessary since the default assumption for
  block devices changed in 3.9)"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
  rbd: require stable pages if message data CRCs are enabled

drivers/block/rbd.c

@@ -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;