jbd2: add lockdep support

Ported from similar patch for the jbd layer.

Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 98a2bc5..2cbf6fd 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -418,6 +418,10 @@
 	unsigned int	h_sync:		1;	/* sync-on-close */
 	unsigned int	h_jdata:	1;	/* force data journaling */
 	unsigned int	h_aborted:	1;	/* fatal error on handle */
+
+#ifdef CONFIG_DEBUG_LOCK_ALLOC
+	struct lockdep_map	h_lockdep_map;
+#endif
 };