--- /dev/null
+#ifndef _IPXE_MEMBLOCK_H
+#define _IPXE_MEMBLOCK_H
+
+/** @file
+ *
+ * Largest memory block
+ *
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <stdint.h>
+#include <ipxe/uaccess.h>
+
+extern size_t largest_memblock ( userptr_t *start );
+
+#endif /* _IPXE_MEMBLOCK_H */