Push BKL down into ->remount_fs()

[xfs, btrfs, capifs, shmem don't need BKL, exempt]

Signed-off-by: Alessio Igor Bogani <abogani@texware.it>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index c17200a..012c425 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3422,6 +3422,8 @@
 	int i;
 #endif
 
+	lock_kernel();
+
 	/* Store the original options */
 	lock_super(sb);
 	old_sb_flags = sb->s_flags;
@@ -3558,6 +3560,7 @@
 			kfree(old_opts.s_qf_names[i]);
 #endif
 	unlock_super(sb);
+	unlock_kernel();
 	return 0;
 
 restore_opts:
@@ -3578,6 +3581,7 @@
 	}
 #endif
 	unlock_super(sb);
+	unlock_kernel();
 	return err;
 }