File-copy from v4.4.100

This is the result of 'cp' from a linux-stable tree with the 'v4.4.100'
tag checked out (commit 26d6298789e695c9f627ce49a7bbd2286405798a) on
git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git

Please refer to that tree for all history prior to this point.

Change-Id: I8a9ee2aea93cd29c52c847d0ce33091a73ae6afe
diff --git a/arch/arm/mm/l2c-common.c b/arch/arm/mm/l2c-common.c
new file mode 100644
index 0000000..10a3cf2
--- /dev/null
+++ b/arch/arm/mm/l2c-common.c
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2010 ARM Ltd.
+ * Written by Catalin Marinas <catalin.marinas@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/bug.h>
+#include <linux/smp.h>
+#include <asm/outercache.h>
+
+void outer_disable(void)
+{
+	WARN_ON(!irqs_disabled());
+	WARN_ON(num_online_cpus() > 1);
+
+	if (outer_cache.disable)
+		outer_cache.disable();
+}