jbd: jbd-debug and jbd2-debug should be writable

jbd-debug and jbd2-debug is currently read-only (S_IRUGO), which is not
correct. Make it writable so that we can start debuging.
Signed-off-by: Yin Kangkai <kangkai.yin@intel.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jan Kara <jack@suse.cz>

fs/jbd/journal.c

@@ -1913,7 +1913,7 @@ static void __init jbd_create_debugfs_entry(void)
 {
 	jbd_debugfs_dir = debugfs_create_dir("jbd", NULL);
 	if (jbd_debugfs_dir)
-		jbd_debug = debugfs_create_u8("jbd-debug", S_IRUGO,
+		jbd_debug = debugfs_create_u8("jbd-debug", S_IRUGO | S_IWUSR,
 					       jbd_debugfs_dir,
 					       &journal_enable_debug);
 }

fs/jbd2/journal.c

@@ -2115,7 +2115,8 @@ static void __init jbd2_create_debugfs_entry(void)
 {
 	jbd2_debugfs_dir = debugfs_create_dir("jbd2", NULL);
 	if (jbd2_debugfs_dir)
-		jbd2_debug = debugfs_create_u8(JBD2_DEBUG_NAME, S_IRUGO,
+		jbd2_debug = debugfs_create_u8(JBD2_DEBUG_NAME,
+					       S_IRUGO | S_IWUSR,
 					       jbd2_debugfs_dir,
 					       &jbd2_journal_enable_debug);
 }