commit c4ce867fdad200dfd8aa8cbe1eabc26c14c51635
author Goldwyn Rodrigues <rgoldwyn@suse.com> Sat Mar 29 10:20:02 2014 -0500
committer Goldwyn Rodrigues <rgoldwyn@suse.com> Mon Feb 23 07:28:42 2015 -0600
tree 529e265c90fbc91a3d4fe8a327f9d7ff9a284890
parent edb39c9deda87da5aad9c090e2e8eaf8470c852c

Introduce md_cluster_info

md_cluster_info stores the cluster information in the MD device.

The join() is called when mddev detects it is a clustered device.
The main responsibilities are:
	1. Setup a DLM lockspace
	2. Setup all initial locks such as super block locks and bitmap lock (will come later)

The leave() clears up the lockspace and all the locks held.

Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>

drivers/md/md.c

diff --git a/drivers/md/md.c b/drivers/md/md.c
index 57ecb51..3387f94 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -7279,6 +7279,8 @@
 
 void md_cluster_stop(struct mddev *mddev)
 {
+	if (!md_cluster_ops)
+		return;
 	md_cluster_ops->leave(mddev);
 	module_put(md_cluster_mod);
 }