diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 70dd3b1..51cd689 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -420,6 +420,11 @@
 	struct inode			*osb_tl_inode;
 	struct buffer_head		*osb_tl_bh;
 	struct delayed_work		osb_truncate_log_wq;
+	/*
+	 * How many clusters in our truncate log.
+	 * It must be protected by osb_tl_inode->i_mutex.
+	 */
+	unsigned int truncated_clusters;
 
 	struct ocfs2_node_map		osb_recovering_orphan_dirs;
 	unsigned int			*osb_orphan_wipes;