2 files changed, 51 insertions, 1 deletions

diff --git a/mm/Makefile b/mm/Makefile
index f10c753dce6d..0b8f73f2ed16 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -10,7 +10,7 @@ mmu-$(CONFIG_MMU)	:= fremap.o highmem.o madvise.o memory.o mincore.o \
 obj-y                   := bootmem.o filemap.o mempool.o oom_kill.o fadvise.o \
                            page_alloc.o page-writeback.o pdflush.o \
                            readahead.o swap.o truncate.o vmscan.o \
-                           prio_tree.o util.o $(mmu-y)
+                           prio_tree.o util.o mmzone.o $(mmu-y)
 
 obj-$(CONFIG_SWAP)      += page_io.o swap_state.o swapfile.o thrash.o
 obj-$(CONFIG_HUGETLBFS) += hugetlb.o
diff --git a/mm/mmzone.c b/mm/mmzone.c
new file mode 100644
index 000000000000..b022370e612e
--- /dev/null
+++ b/mm/mmzone.c
@@ -0,0 +1,50 @@
+/*
+ * linux/mm/mmzone.c
+ *
+ * management codes for pgdats and zones.
+ */
+
+
+#include <linux/config.h>
+#include <linux/stddef.h>
+#include <linux/mmzone.h>
+#include <linux/module.h>
+
+struct pglist_data *first_online_pgdat(void)
+{
+        return NODE_DATA(first_online_node);
+}
+
+EXPORT_SYMBOL(first_online_pgdat);
+
+struct pglist_data *next_online_pgdat(struct pglist_data *pgdat)
+{
+        int nid = next_online_node(pgdat->node_id);
+
+        if (nid == MAX_NUMNODES)
+                return NULL;
+        return NODE_DATA(nid);
+}
+EXPORT_SYMBOL(next_online_pgdat);
+
+
+/*
+ * next_zone - helper magic for for_each_zone()
+ */
+struct zone *next_zone(struct zone *zone)
+{
+        pg_data_t *pgdat = zone->zone_pgdat;
+
+        if (zone < pgdat->node_zones + MAX_NR_ZONES - 1)
+                zone++;
+        else {
+                pgdat = next_online_pgdat(pgdat);
+                if (pgdat)
+                        zone = pgdat->node_zones;
+                else
+                        zone = NULL;
+        }
+        return zone;
+}
+EXPORT_SYMBOL(next_zone);
+