[PATCH] x86_64: Support memory hotadd without sparsemem

Memory hotadd doesn't need SPARSEMEM, but can be handled by just preallocating
mem_maps. This only needs some untangling of ifdefs to enable the necessary
code even without SPARSEMEM.

Originally from Keith Mannthey, hacked by AK.

Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 9 insertions, 8 deletions

diff --git a/include/linux/init.h b/include/linux/init.h
index ed0ac7c39fdc..93dcbe1abb4c 100644
--- a/include/linux/init.h
+++ b/include/linux/init.h
@@ -245,7 +245,8 @@ void __init parse_early_param(void);
 #define __cpuexitdata   __exitdata
 #endif
 
-#ifdef CONFIG_MEMORY_HOTPLUG
+#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
+        || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
 #define __meminit
 #define __meminitdata
 #define __memexit
diff --git a/include/linux/memory_hotplug.h b/include/linux/memory_hotplug.h
index 968b1aa3732c..4ca3e6ad03ec 100644
--- a/include/linux/memory_hotplug.h
+++ b/include/linux/memory_hotplug.h
@@ -58,8 +58,6 @@ extern int add_one_highpage(struct page *page, int pfn, int bad_ppro);
 /* need some defines for these for archs that don't support it */
 extern void online_page(struct page *page);
 /* VM interface that may be used by firmware interface */
-extern int add_memory(u64 start, u64 size);
-extern int remove_memory(u64 start, u64 size);
 extern int online_pages(unsigned long, unsigned long);
 
 /* reasonably generic interface to expand the physical pages in a zone  */
@@ -92,11 +90,6 @@ static inline int mhp_notimplemented(const char *func)
         return -ENOSYS;
 }
 
-static inline int __add_pages(struct zone *zone, unsigned long start_pfn,
-        unsigned long nr_pages)
-{
-        return mhp_notimplemented(__FUNCTION__);
-}
 #endif /* ! CONFIG_MEMORY_HOTPLUG */
 static inline int __remove_pages(struct zone *zone, unsigned long start_pfn,
         unsigned long nr_pages)
@@ -105,4 +98,11 @@ static inline int __remove_pages(struct zone *zone, unsigned long start_pfn,
         dump_stack();
         return -ENOSYS;
 }
+
+#if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \
+        || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE)
+extern int add_memory(u64 start, u64 size);
+extern int remove_memory(u64 start, u64 size);
+#endif
+
 #endif /* __LINUX_MEMORY_HOTPLUG_H */