[Patch1/4]: fake numa for x86_64 patch

[Rohit Seth <rohitseth@google.com>]

This patch provides a IO hole size in a given address range.

Signed-off-by: David Rientjes <reintjes@google.com>
Signed-off-by: Paul Menage <menage@google.com>
Signed-off-by: Rohit Seth <rohitseth@google.com>

--- linux-2.6.19-rc5-mm2.org/include/asm-x86_64/e820.h	2006-11-22 12:20:39.000000000 -0800
+++ linux-2.6.19-rc5-mm2/include/asm-x86_64/e820.h	2006-11-22 12:17:25.000000000 -0800
@@ -46,6 +46,7 @@ extern void e820_mark_nosave_regions(voi
 extern void e820_print_map(char *who);
 extern int e820_any_mapped(unsigned long start, unsigned long end, unsigned type);
 extern int e820_all_mapped(unsigned long start, unsigned long end, unsigned type);
+extern unsigned long e820_hole_size(unsigned long start, unsigned long end);
 
 extern void e820_setup_gap(void);
 extern void e820_register_active_regions(int nid,
--- linux-2.6.19-rc5-mm2.org/arch/x86_64/kernel/e820.c	2006-11-22 12:20:55.000000000 -0800
+++ linux-2.6.19-rc5-mm2/arch/x86_64/kernel/e820.c	2006-11-21 18:48:15.000000000 -0800
@@ -184,6 +184,38 @@ unsigned long __init e820_end_of_ram(voi
 }
 
 /*
+ * Find the hole size in the range.
+ */
+unsigned long __init e820_hole_size(unsigned long start, unsigned long end)
+{
+	unsigned long ram = 0;
+	int i;
+
+	for (i = 0; i < e820.nr_map; i++) {
+		struct e820entry *ei = &e820.map[i];
+		unsigned long last, addr;
+
+		if (ei->type != E820_RAM ||
+		    ei->addr+ei->size <= start ||
+		    ei->addr >= end)
+			continue;
+
+		addr = round_up(ei->addr, PAGE_SIZE);
+		if (addr < start)
+			addr = start;
+
+		last = round_down(ei->addr + ei->size, PAGE_SIZE);
+		if (last >= end)
+			last = end;
+
+		if (last > addr)
+			ram += last - addr;
+	}
+	return ((end - start) - ram);
+}
+
+
+/*
  * Mark e820 reserved areas as busy for the resource manager.
  */
 void __init e820_reserve_resources(void)