drbd: discard_zeroes_if_aligned allows "thin" resync for discard_zeroes_data=0

Even if discard_zeroes_data != 0,
if discard_zeroes_if_aligned is set, we assume we can reliably
zero-out/discard using the drbd_issue_peer_discard() helper.

Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This commit is contained in:
Lars Ellenberg 2016-06-14 00:26:29 +02:00 committed by Jens Axboe
parent af61494ad4
commit 65f5be3579

View File

@ -1408,9 +1408,12 @@ static void sanitize_disk_conf(struct drbd_device *device, struct disk_conf *dis
if (disk_conf->al_extents > drbd_al_extents_max(nbc))
disk_conf->al_extents = drbd_al_extents_max(nbc);
if (!blk_queue_discard(q) || !q->limits.discard_zeroes_data) {
disk_conf->rs_discard_granularity = 0; /* disable feature */
drbd_info(device, "rs_discard_granularity feature disabled\n");
if (!blk_queue_discard(q)
|| (!q->limits.discard_zeroes_data && !disk_conf->discard_zeroes_if_aligned)) {
if (disk_conf->rs_discard_granularity) {
disk_conf->rs_discard_granularity = 0; /* disable feature */
drbd_info(device, "rs_discard_granularity feature disabled\n");
}
}
if (disk_conf->rs_discard_granularity) {