[PATCH] hot-add-mem x86_64: use CONFIG_MEMORY_HOTPLUG_RESERVE

The api for hot-add memory already has a construct for finding nodes based on
an address, memory_add_physaddr_to_nid.  This patch allows the fucntion to do
something besides return 0.  It uses the nodes_add infomation to lookup to
node info for a hot add event.
Signed-off-by: Keith Mannthey <kmannth@us.ibm.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/x86_64/mm/init.c

@@ -474,12 +474,12 @@ int arch_add_memory(int nid, u64 start, u64 size)
 	unsigned long nr_pages = size >> PAGE_SHIFT;
 	int ret;
 
+	init_memory_mapping(start, (start + size -1));
+
 	ret = __add_pages(zone, start_pfn, nr_pages);
 	if (ret)
 		goto error;
 
-	init_memory_mapping(start, (start + size -1));
-
 	return ret;
 error:
 	printk("%s: Problem encountered in __add_pages!\n", __func__);
@@ -501,7 +501,16 @@ int memory_add_physaddr_to_nid(u64 start)
 EXPORT_SYMBOL_GPL(memory_add_physaddr_to_nid);
 #endif
 
-#else /* CONFIG_MEMORY_HOTPLUG */
+#ifndef CONFIG_ACPI_NUMA
+int memory_add_physaddr_to_nid(u64 start)
+{
+	return 0;
+}
+#endif
+
+#endif /* CONFIG_MEMORY_HOTPLUG */
+
+#ifdef CONFIG_MEMORY_HOTPLUG_RESERVE
 /*
  * Memory Hotadd without sparsemem. The mem_maps have been allocated in advance,
  * just online the pages.
@@ -527,7 +536,7 @@ int __add_pages(struct zone *z, unsigned long start_pfn, unsigned long nr_pages)
 	}
 	return err;
 }
-#endif /* CONFIG_MEMORY_HOTPLUG */
+#endif
 
 static struct kcore_list kcore_mem, kcore_vmalloc, kcore_kernel, kcore_modules,
 			 kcore_vsyscall;

mm/memory_hotplug.c

@@ -26,6 +26,36 @@
 
 #include <asm/tlbflush.h>
 
+/* add this memory to iomem resource */
+static struct resource *register_memory_resource(u64 start, u64 size)
+{
+	struct resource *res;
+	res = kzalloc(sizeof(struct resource), GFP_KERNEL);
+	BUG_ON(!res);
+
+	res->name = "System RAM";
+	res->start = start;
+	res->end = start + size - 1;
+	res->flags = IORESOURCE_MEM;
+	if (request_resource(&iomem_resource, res) < 0) {
+		printk("System RAM resource %llx - %llx cannot be added\n",
+		(unsigned long long)res->start, (unsigned long long)res->end);
+		kfree(res);
+		res = NULL;
+	}
+	return res;
+}
+
+static void release_memory_resource(struct resource *res)
+{
+	if (!res)
+		return;
+	release_resource(res);
+	kfree(res);
+	return;
+}
+
+
 #ifdef CONFIG_MEMORY_HOTPLUG_SPARSE
 static int __add_zone(struct zone *zone, unsigned long phys_start_pfn)
 {
@@ -223,36 +253,6 @@ static void rollback_node_hotadd(int nid, pg_data_t *pgdat)
 	return;
 }
 
-/* add this memory to iomem resource */
-static struct resource *register_memory_resource(u64 start, u64 size)
-{
-	struct resource *res;
-	res = kzalloc(sizeof(struct resource), GFP_KERNEL);
-	BUG_ON(!res);
-
-	res->name = "System RAM";
-	res->start = start;
-	res->end = start + size - 1;
-	res->flags = IORESOURCE_MEM;
-	if (request_resource(&iomem_resource, res) < 0) {
-		printk("System RAM resource %llx - %llx cannot be added\n",
-		(unsigned long long)res->start, (unsigned long long)res->end);
-		kfree(res);
-		res = NULL;
-	}
-	return res;
-}
-
-static void release_memory_resource(struct resource *res)
-{
-	if (!res)
-		return;
-	release_resource(res);
-	kfree(res);
-	return;
-}
-
-
 
 int add_memory(int nid, u64 start, u64 size)
 {