ARM: outer cache: add WARN_ON() to outer_disable()

Add WARN_ON() conditions to outer_disable() to ensure that its
requirements aren't violated.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

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();
+}