tree 0a7c2dc1c3159c2af14d87c67ca83e158b2c78b5
parent d30a2605be9d5132d95944916e8f578fcfe4f976
author David Woodhouse <David.Woodhouse@intel.com> 1218296540 +0100
committer Jens Axboe <jens.axboe@oracle.com> 1223535362 +0200

Allow elevators to sort/merge discard requests

But blkdev_issue_discard() still emits requests which are interpreted as
soft barriers, because naïve callers might otherwise issue subsequent
writes to those same sectors, which might cross on the queue (if they're
reallocated quickly enough).

Callers still _can_ issue non-barrier discard requests, but they have to
take care of queue ordering for themselves.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>