pfn_valid for x86_64

These are the minimal definitions to make x86_64 work with the new
pfn_valid. It does not add support for a virtual memory map.

Signed-off-by: Christoph Lameter <clameter@sgi.com>

Index: linux-2.6.18-mm3/arch/x86_64/kernel/setup.c
===================================================================
--- linux-2.6.18-mm3.orig/arch/x86_64/kernel/setup.c	2006-10-04 21:04:54.000000000 -0700
+++ linux-2.6.18-mm3/arch/x86_64/kernel/setup.c	2006-10-04 21:18:04.000000000 -0700
@@ -386,6 +386,9 @@
 	 * we are rounding upwards:
 	 */
 	end_pfn = e820_end_of_ram();
+#if defined(CONFIG_VIRTUAL_MEM_MAP) || defined(CONFIG_FLATMEM)
+	max_mapnr = end_pfn;
+#endif
 	num_physpages = end_pfn;
 
 	check_efer();
Index: linux-2.6.18-mm3/include/asm-x86_64/page.h
===================================================================
--- linux-2.6.18-mm3.orig/include/asm-x86_64/page.h	2006-09-19 20:42:06.000000000 -0700
+++ linux-2.6.18-mm3/include/asm-x86_64/page.h	2006-10-04 21:15:12.000000000 -0700
@@ -121,9 +121,6 @@
 #define __va(x)			((void *)((unsigned long)(x)+PAGE_OFFSET))
 #define __boot_va(x)		__va(x)
 #define __boot_pa(x)		__pa(x)
-#ifdef CONFIG_FLATMEM
-#define pfn_valid(pfn)		((pfn) < end_pfn)
-#endif
 
 #define virt_to_page(kaddr)	pfn_to_page(__pa(kaddr) >> PAGE_SHIFT)
 #define virt_addr_valid(kaddr)	pfn_valid(__pa(kaddr) >> PAGE_SHIFT)