ocfs2: document access rules for blocked_lock_list

ocfs2_super->blocked_lock_list and ocfs2_super->blocked_lock_count have some usage restrictions which aren't immediately obvious to anyone reading the code. It's a good idea to document this so that we avoid making costly mistakes in the future. Signed-off-by: Mark Fasheh <[email protected]>
kawasaki · Jan 25, 2008 · 7ec373c · 7ec373c
1 parent 116ba5d
commit 7ec373c
Showing 1 changed file with 6 additions and 0 deletions.
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
@@ -262,6 +262,12 @@ struct ocfs2_super
 	unsigned long dc_wake_sequence;
 	unsigned long dc_work_sequence;
 
+	/*
+	 * Any thread can add locks to the list, but the downconvert
+	 * thread is the only one allowed to remove locks. Any change
+	 * to this rule requires updating
+	 * ocfs2_downconvert_thread_do_work().
+	 */
 	struct list_head blocked_lock_list;
 	unsigned long blocked_lock_count;