[PATCH 2/2] dm-mpath: Allow 'default' hardware handler

[Hannes Reinecke <hare@suse.de>]

This patch introduces a 'default' hardware handler for dm-mpath.
When specifying '1 default' dm-multipath will be using the currently
attached hardware handler.

Signed-off-by: Hannes Reinecke <hare@suse.de>
---
 drivers/md/dm-mpath.c |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 922a338..bbf950f 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -586,15 +586,19 @@ static struct pgpath *parse_path(struct dm_arg_set *as, struct path_selector *ps
 
 	if (m->hw_handler_name) {
 		struct request_queue *q = bdev_get_queue(p->path.dev->bdev);
+		char *hw_handler = NULL;
 
-		r = scsi_dh_attach(q, m->hw_handler_name);
+		if (strncmp(m->hw_handler_name, "default", 6))
+			hw_handler = m->hw_handler_name;
+		
+		r = scsi_dh_attach(q, hw_handler);
 		if (r == -EBUSY) {
 			/*
 			 * Already attached to different hw_handler,
 			 * try to reattach with correct one.
 			 */
 			scsi_dh_detach(q);
-			r = scsi_dh_attach(q, m->hw_handler_name);
+			r = scsi_dh_attach(q, hw_handler);
 		}
 
 		if (r < 0) {
-- 
1.7.7