VIRTUAL_MEM_MAP does not need node_mem_map

There is no need for a per node mem_map pointer with a virtual memory map.

Remove #ifdefs and special casing in alloc_node_mem_map (we can drop the
whole function plus the definition of node_mem_map if we decide to no longeri
support per node memory maps and instead use always virtual memory maps).

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

Index: linux-2.6.18-mm3/arch/ia64/mm/discontig.c
===================================================================
--- linux-2.6.18-mm3.orig/arch/ia64/mm/discontig.c	2006-10-05 13:29:45.000000000 -0500
+++ linux-2.6.18-mm3/arch/ia64/mm/discontig.c	2006-10-05 17:07:30.645002533 -0500
@@ -708,10 +708,6 @@ void __init paging_init(void)
 	for_each_online_node(node) {
 		num_physpages += mem_data[node].num_physpages;
 		pfn_offset = mem_data[node].min_pfn;
-
-#ifdef CONFIG_VIRTUAL_MEM_MAP
-		NODE_DATA(node)->node_mem_map = mem_map + pfn_offset;
-#endif
 		if (mem_data[node].max_pfn > max_pfn)
 			max_pfn = mem_data[node].max_pfn;
 	}
Index: linux-2.6.18-mm3/include/linux/mmzone.h
===================================================================
--- linux-2.6.18-mm3.orig/include/linux/mmzone.h	2006-10-05 13:29:45.000000000 -0500
+++ linux-2.6.18-mm3/include/linux/mmzone.h	2006-10-05 17:08:58.569556550 -0500
@@ -380,7 +380,7 @@ typedef struct pglist_data {
 	struct zone node_zones[MAX_NR_ZONES];
 	struct zonelist node_zonelists[MAX_NR_ZONES];
 	int nr_zones;
-#ifdef CONFIG_FLAT_NODE_MEM_MAP
+#if !defined(CONFIG_VIRTUAL_MEM_MAP) && defined(CONFIG_FLAT_NODE_MEM_MAP)
 	struct page *node_mem_map;
 #endif
 	struct bootmem_data *bdata;
Index: linux-2.6.18-mm3/mm/page_alloc.c
===================================================================
--- linux-2.6.18-mm3.orig/mm/page_alloc.c	2006-10-05 13:29:46.000000000 -0500
+++ linux-2.6.18-mm3/mm/page_alloc.c	2006-10-05 13:47:10.000000000 -0500
@@ -2536,30 +2536,28 @@ static void __meminit free_area_init_cor
 
 static void __init alloc_node_mem_map(struct pglist_data *pgdat)
 {
+#ifndef CONFIG_VIRTUAL_MEM_MAP
 	/* Skip empty nodes */
 	if (!pgdat->node_spanned_pages)
 		return;
 
 #ifdef CONFIG_FLAT_NODE_MEM_MAP
-	/* ia64 gets its own node_mem_map, before this, without bootmem */
-	if (!pgdat->node_mem_map) {
-		unsigned long size, start, end;
-		struct page *map;
-
-		/*
-		 * The zone's endpoints aren't required to be MAX_ORDER
-		 * aligned but the node_mem_map endpoints must be in order
-		 * for the buddy allocator to function correctly.
-		 */
-		start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
-		end = pgdat->node_start_pfn + pgdat->node_spanned_pages;
-		end = ALIGN(end, MAX_ORDER_NR_PAGES);
-		size =  (end - start) * sizeof(struct page);
-		map = alloc_remap(pgdat->node_id, size);
-		if (!map)
-			map = alloc_bootmem_node(pgdat, size);
-		pgdat->node_mem_map = map + (pgdat->node_start_pfn - start);
-	}
+	unsigned long size, start, end;
+	struct page *map;
+
+	/*
+	 * The zone's endpoints aren't required to be MAX_ORDER
+	 * aligned but the node_mem_map endpoints must be in order
+	 * for the buddy allocator to function correctly.
+	 */
+	start = pgdat->node_start_pfn & ~(MAX_ORDER_NR_PAGES - 1);
+	end = pgdat->node_start_pfn + pgdat->node_spanned_pages;
+	end = ALIGN(end, MAX_ORDER_NR_PAGES);
+	size =  (end - start) * sizeof(struct page);
+	map = alloc_remap(pgdat->node_id, size);
+	if (!map)
+		map = alloc_bootmem_node(pgdat, size);
+	pgdat->node_mem_map = map + (pgdat->node_start_pfn - start);
 #ifdef CONFIG_FLATMEM
 	/*
 	 * With no DISCONTIG, the global mem_map is just set as node 0's
@@ -2573,6 +2571,7 @@ static void __init alloc_node_mem_map(st
 	}
 #endif
 #endif /* CONFIG_FLAT_NODE_MEM_MAP */
+#endif /* CONFIG_VIRTUAL_MEM_MAP */
 }
 
 void __meminit free_area_init_node(int nid, struct pglist_data *pgdat,