+static void __init trim_bios_range(void)
+{
+ /*
+ * A special case is the first 4Kb of memory;
+ * This is a BIOS owned area, not kernel ram, but generally
+ * not listed as such in the E820 table.
+ */
+ e820_update_range(0, PAGE_SIZE, E820_RAM, E820_RESERVED);
+ /*
+ * special case: Some BIOSen report the PC BIOS
+ * area (640->1Mb) as ram even though it is not.
+ * take them out.
+ */
+ e820_remove_range(BIOS_BEGIN, BIOS_END - BIOS_BEGIN, E820_RAM, 1);
+ sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
+}
+