dm mpath: remove repeat_count support from multipath core

Preparation for making __multipath_map() avoid taking the m->lock
spinlock -- in favor of using RCU locking.

repeat_count was primarily for bio-based DM multipath's benefit.  There
is really no need for it anymore now that DM multipath is request-based.
As such, repeat_count > 1 is no longer honored and a warning is
displayed if the user attempts to use a value > 1.  This is a temporary
change for the round-robin path-selector (as a later commit will restore
its support for repeat_count > 1).

Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 8 insertions, 3 deletions

diff --git a/drivers/md/dm-round-robin.c b/drivers/md/dm-round-robin.c
index 6ab1192cdd5f..65ffdc3403b6 100644
--- a/drivers/md/dm-round-robin.c
+++ b/drivers/md/dm-round-robin.c
@@ -17,6 +17,8 @@
 #include <linux/module.h>
 
 #define DM_MSG_PREFIX "multipath round-robin"
+#define RR_MIN_IO     1
+#define RR_VERSION    "1.1.0"
 
 /*-----------------------------------------------------------------
  * Path-handling code, paths are held in lists
@@ -41,8 +43,6 @@ static void free_paths(struct list_head *paths)
  * Round-robin selector
  *---------------------------------------------------------------*/
 
-#define RR_MIN_IO		1000
-
 struct selector {
 	struct list_head valid_paths;
 	struct list_head invalid_paths;
@@ -127,6 +127,11 @@ static int rr_add_path(struct path_selector *ps, struct dm_path *path,
 		return -EINVAL;
 	}
 
+	if (repeat_count > 1) {
+		DMWARN_LIMIT("repeat_count > 1 is deprecated, using 1 instead");
+		repeat_count = 1;
+	}
+
 	/* allocate the path */
 	pi = kmalloc(sizeof(*pi), GFP_KERNEL);
 	if (!pi) {
@@ -198,7 +203,7 @@ static int __init dm_rr_init(void)
 	if (r < 0)
 		DMERR("register failed %d", r);
 
-	DMINFO("version 1.0.0 loaded");
+	DMINFO("version " RR_VERSION " loaded");
 
 	return r;
 }