1 files changed, 33 insertions, 0 deletions

diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c
index 93a5c53e3423..be5c506779a7 100644
--- a/arch/powerpc/mm/mem.c
+++ b/arch/powerpc/mm/mem.c
@@ -129,6 +129,39 @@ int __devinit arch_add_memory(int nid, u64 start, u64 size)
         return __add_pages(zone, start_pfn, nr_pages);
 }
 
+#ifdef CONFIG_MEMORY_HOTREMOVE
+int remove_memory(u64 start, u64 size)
+{
+        unsigned long start_pfn, end_pfn;
+        int ret;
+
+        start_pfn = start >> PAGE_SHIFT;
+        end_pfn = start_pfn + (size >> PAGE_SHIFT);
+        ret = offline_pages(start_pfn, end_pfn, 120 * HZ);
+        if (ret)
+                goto out;
+        /* Arch-specific calls go here - next patch */
+out:
+        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)