drbd: announce FLUSH/FUA capability to upper layers

Unconditionally announce FLUSH/FUA to upper layers.
If the lower layers on either node do not actually support this,
generic_make_request() will deal with it.

If this causes performance regressions on your setup,
make sure there are no volatile caches involved,
and mount -o nobarrier or equivalent.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
This commit is contained in:
Lars Ellenberg
2012-06-25 19:15:38 +02:00
committed by Philipp Reisner
parent db141b2f42
commit a73ff3231d
4 changed files with 23 additions and 8 deletions

View File

@@ -3636,6 +3636,7 @@ struct drbd_conf *drbd_new_device(unsigned int minor)
q->backing_dev_info.congested_data = mdev;
blk_queue_make_request(q, drbd_make_request);
blk_queue_flush(q, REQ_FLUSH | REQ_FUA);
/* Setting the max_hw_sectors to an odd value of 8kibyte here
This triggers a max_bio_size message upon first attach or connect */
blk_queue_max_hw_sectors(q, DRBD_MAX_BIO_SIZE_SAFE >> 8);