diff -Nurp --exclude-from=/home/mcd/.dontdiff linux-2.6.4-vanilla/Documentation/vm/numa linux-2.6.4-nodemask_t-core/Documentation/vm/numa
--- linux-2.6.4-vanilla/Documentation/vm/numa	Wed Mar 10 18:55:35 2004
+++ linux-2.6.4-nodemask_t-core/Documentation/vm/numa	Thu Mar 11 11:59:01 2004
@@ -29,7 +29,7 @@ Each node's page allocation data structu
 into a pg_data_t. The bootmem_data_t is just one part of this. To 
 make the code look uniform between NUMA and regular UMA platforms, 
 UMA platforms have a statically allocated pg_data_t too (contig_page_data).
-For the sake of uniformity, the variable "numnodes" is also defined
+For the sake of uniformity, the variable "node_online_map" is also defined
 for all platforms. As we run benchmarks, we might decide to NUMAize 
 more variables like low_on_memory, nr_free_pages etc into the pg_data_t.
 
diff -Nurp --exclude-from=/home/mcd/.dontdiff linux-2.6.4-vanilla/include/linux/gfp.h linux-2.6.4-nodemask_t-core/include/linux/gfp.h
--- linux-2.6.4-vanilla/include/linux/gfp.h	Wed Mar 10 18:55:24 2004
+++ linux-2.6.4-nodemask_t-core/include/linux/gfp.h	Thu Mar 11 11:59:01 2004
@@ -58,7 +58,7 @@
 
 /*
  * We get the zone list from the current node and the gfp_mask.
- * This zone list contains a maximum of MAXNODES*MAX_NR_ZONES zones.
+ * This zone list contains a maximum of MAX_NUMNODES*MAX_NR_ZONES zones.
  *
  * For the normal case of non-DISCONTIGMEM systems the NODE_DATA() gets
  * optimized to &contig_page_data at compile-time.
diff -Nurp --exclude-from=/home/mcd/.dontdiff linux-2.6.4-vanilla/include/linux/topology.h linux-2.6.4-nodemask_t-core/include/linux/topology.h
--- linux-2.6.4-vanilla/include/linux/topology.h	Wed Mar 10 18:55:36 2004
+++ linux-2.6.4-nodemask_t-core/include/linux/topology.h	Mon Mar 15 17:11:33 2004
@@ -43,15 +43,20 @@
 	})
 #endif
 
-static inline int __next_node_with_cpus(int node)
+static inline int __next_node_with_cpus(int last_node)
 {
-	do
-		++node;
-	while (node < numnodes && !nr_cpus_node(node));
-	return node;
+	int nid;
+	for_each_online_node(nid)
+		if (nr_cpus_node(nid) && nid > last_node)
+			return nid;
+
+	return MAX_NUMNODES;
 }
 
-#define for_each_node_with_cpus(node) \
-	for (node = 0; node < numnodes; node = __next_node_with_cpus(node))
+/* Assumes first_node(node_online_map) will have CPUs */
+#define for_each_node_with_cpus(node)			\
+	for(node = first_node(node_online_map);		\
+		node < MAX_NUMNODES;			\
+		node = __next_node_with_cpus(node))
 
 #endif /* _LINUX_TOPOLOGY_H */
diff -Nurp --exclude-from=/home/mcd/.dontdiff linux-2.6.4-vanilla/kernel/sched.c linux-2.6.4-nodemask_t-core/kernel/sched.c
--- linux-2.6.4-vanilla/kernel/sched.c	Wed Mar 10 18:55:43 2004
+++ linux-2.6.4-nodemask_t-core/kernel/sched.c	Thu Mar 11 11:59:01 2004
@@ -1088,7 +1088,7 @@ void sched_balance_exec(void)
 {
 	int new_cpu;
 
-	if (numnodes > 1) {
+	if (num_online_nodes() > 1) {
 		new_cpu = sched_best_cpu(current);
 		if (new_cpu != smp_processor_id())
 			sched_migrate_task(current, new_cpu);
diff -Nurp --exclude-from=/home/mcd/.dontdiff linux-2.6.4-vanilla/mm/page_alloc.c linux-2.6.4-nodemask_t-core/mm/page_alloc.c
--- linux-2.6.4-vanilla/mm/page_alloc.c	Wed Mar 10 18:55:22 2004
+++ linux-2.6.4-nodemask_t-core/mm/page_alloc.c	Mon Mar 15 17:24:48 2004
@@ -34,12 +34,12 @@
 
 #include <asm/tlbflush.h>
 
-DECLARE_BITMAP(node_online_map, MAX_NUMNODES);
+nodemask_t node_online_map = NODE_MASK_NONE;
+nodemask_t node_possible_map = NODE_MASK_ALL;
 struct pglist_data *pgdat_list;
 unsigned long totalram_pages;
 unsigned long totalhigh_pages;
 int nr_swap_pages;
-int numnodes = 1;
 int sysctl_lower_zone_protection = 0;
 
 EXPORT_SYMBOL(totalram_pages);
@@ -1115,9 +1115,13 @@ static void __init build_zonelists(pg_da
  		 * zones coming right after the local ones are those from
  		 * node N+1 (modulo N)
  		 */
- 		for (node = local_node + 1; node < numnodes; node++)
+ 		for (node = next_node(local_node, node_online_map);
+		     node < MAX_NUMNODES;
+		     node = next_node(node, node_online_map))
  			j = build_zonelists_node(NODE_DATA(node), zonelist, j, k);
- 		for (node = 0; node < local_node; node++)
+ 		for (node = first_node(node_online_map);
+		     node < local_node;
+		     node = next_node(node, node_online_map))
  			j = build_zonelists_node(NODE_DATA(node), zonelist, j, k);
  
 		zonelist->zones[j++] = NULL;
@@ -1128,9 +1132,9 @@ void __init build_all_zonelists(void)
 {
 	int i;
 
-	for(i = 0 ; i < numnodes ; i++)
+	for_each_online_node(i)
 		build_zonelists(NODE_DATA(i));
-	printk("Built %i zonelists\n", numnodes);
+	printk("Built %i zonelists\n", num_online_nodes());
 }
 
 /*