---

yaml
---
r: 84879
b: refs/heads/master
c: a99824f
h: refs/heads/master
i:
  84877: 9cf610e
  84875: 08268e5
  84871: b1e9b9e
  84863: cec10b8
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 1482471d19e77d794012dbacaa65c44ceaae37bb
+refs/heads/master: a99824f327c748b2753f4fa570eb1fefcd6a9c4d

trunk/arch/powerpc/Kconfig

@@ -272,6 +272,9 @@ config HOTPLUG_CPU
 config ARCH_ENABLE_MEMORY_HOTPLUG
 	def_bool y
 
+config ARCH_HAS_WALK_MEMORY
+	def_bool y
+
 config ARCH_ENABLE_MEMORY_HOTREMOVE
 	def_bool y
 

trunk/arch/powerpc/mm/mem.c

@@ -145,6 +145,23 @@ int remove_memory(u64 start, u64 size)
 	return ret;
 }
 #endif /* CONFIG_MEMORY_HOTREMOVE */
+
+/*
+ * walk_memory_resource() needs to make sure there is no holes in a given
+ * memory range. On PPC64, since this range comes from /sysfs, the range
+ * is guaranteed to be valid, non-overlapping and can not contain any
+ * holes. By the time we get here (memory add or remove), /proc/device-tree
+ * is updated and correct. Only reason we need to check against device-tree
+ * would be if we allow user-land to specify a memory range through a
+ * system call/ioctl etc. instead of doing offline/online through /sysfs.
+ */
+int
+walk_memory_resource(unsigned long start_pfn, unsigned long nr_pages, void *arg,
+			int (*func)(unsigned long, unsigned long, void *))
+{
+	return  (*func)(start_pfn, nr_pages, arg);
+}
+
 #endif /* CONFIG_MEMORY_HOTPLUG */
 
 void show_mem(void)

trunk/kernel/resource.c

@@ -228,7 +228,7 @@ int release_resource(struct resource *old)
 
 EXPORT_SYMBOL(release_resource);
 
-#ifdef CONFIG_MEMORY_HOTPLUG
+#if defined(CONFIG_MEMORY_HOTPLUG) && !defined(CONFIG_ARCH_HAS_WALK_MEMORY)
 /*
  * Finds the lowest memory reosurce exists within [res->start.res->end)
  * the caller must specify res->start, res->end, res->flags.