Commit 401a18e9 authored Mar 25, 2011 by Jens Axboe

block: fix bug with inserting flush requests as sort/merge



With the introduction of the on-stack plugging, we would assume
that any request being inserted was a normal file system request.
As flush/fua requires a special insert mode, this caused problems.

Fix this up by checking for this in flush_plug_list() and use
the appropriate insert mechanism.

Big thanks goes to Markus Tripplesdorf for tirelessly testing
patches, and to Sergey Senozhatsky for helping find the real
issue.

Reported-by: Markus Tripplesdorf <markus@trippelsdorf.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>

parent 6c510389

block/blk-core.c

+4 −1

Original line number	Diff line number	Diff line
		@@ -2702,6 +2702,9 @@ static void flush_plug_list(struct blk_plug *plug)
		/*
		* rq is already accounted, so use raw insert
		*/
		if (rq->cmd_flags & (REQ_FLUSH \| REQ_FUA))
		__elv_add_request(q, rq, ELEVATOR_INSERT_FLUSH);
		else
		__elv_add_request(q, rq, ELEVATOR_INSERT_SORT_MERGE);
		}