1 files changed, 24 insertions, 0 deletions
diff --git a/arch/um/kernel/maccess.c b/arch/um/kernel/maccess.c
new file mode 100644
index 000000000000..1f3d5c4910d1
--- /dev/null
+++ b/arch/um/kernel/maccess.c
@@ -0,0 +1,24 @@
+/*
+ * Copyright (C) 2013 Richard Weinberger <richrd@nod.at>
+ *
+ * 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/uaccess.h>
+#include <linux/kernel.h>
+#include <os.h>
+
+long probe_kernel_read(void *dst, const void *src, size_t size)
+{
+	void *psrc = (void *)rounddown((unsigned long)src, PAGE_SIZE);
+
+	if ((unsigned long)src < PAGE_SIZE || size <= 0)
+		return -EFAULT;
+
+	if (os_mincore(psrc, size + src - psrc) <= 0)
+		return -EFAULT;
+
+	return __probe_kernel_read(dst, src, size);
+}