Commit 47e627ce authored Oct 29, 2005 by Tejun Heo Committed by Linus Torvalds Oct 29, 2005

[PATCH] blk: fix merge bug in as-iosched



as-iosched deals with aliased requests differently from other ioscheds.

It links together aliased requests using rq->queuelist instead of
spilling alises to dispatch queue like other ioscheds do.  Requests
linked in this way cannot be merged.

Unfortunately, generic q->last_merge handling patch didn't take this
into account and q->last_merge could be set to an aliased request
resulting in Badness, corrupt list and eventually panic.

This explicitly marks aliased requests to be unmergeable.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent fc228a04

drivers/block/as-iosched.c

+1 −0

Original line number	Diff line number	Diff line
		@@ -1344,6 +1344,7 @@ as_add_aliased_request(struct as_data ad, struct as_rq arq, struct as_rq *alia
		* Don't want to have to handle merges.
		*/
		as_del_arq_hash(arq);
		arq->request->flags \|= REQ_NOMERGE;
		}

		/*