ocfs2: Depend on configfs heartbeat items.

ocfs2 mounts require a heartbeat region.  Use the new configfs_depend_item()
facility to actually depend on them so they can't go away from under us.

First, teach cluster/nodemanager.c to depend an item on the o2cb subsystem.
Then teach o2hb_register_callbacks to take a UUID and depend on the
appropriate region.  Finally, teach all users of o2hb to pass a UUID or
NULL if they don't require a pin.

Signed-off-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/fs/ocfs2/cluster/heartbeat.h b/fs/ocfs2/cluster/heartbeat.h
index cc6d40b39771..35397dd5ecdb 100644
--- a/fs/ocfs2/cluster/heartbeat.h
+++ b/fs/ocfs2/cluster/heartbeat.h
@@ -69,8 +69,10 @@ void o2hb_setup_callback(struct o2hb_callback_func *hc,
                          o2hb_cb_func *func,
                          void *data,
                          int priority);
-int o2hb_register_callback(struct o2hb_callback_func *hc);
-void o2hb_unregister_callback(struct o2hb_callback_func *hc);
+int o2hb_register_callback(const char *region_uuid,
+                           struct o2hb_callback_func *hc);
+void o2hb_unregister_callback(const char *region_uuid,
+                              struct o2hb_callback_func *hc);
 void o2hb_fill_node_map(unsigned long *map,
                         unsigned bytes);
 void o2hb_init(void);