From: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>

IA64 memory unplug interface.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/ia64/mm/init.c |   12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff -puN arch/ia64/mm/init.c~memory-unplug-v7-ia64-interface arch/ia64/mm/init.c
--- a/arch/ia64/mm/init.c~memory-unplug-v7-ia64-interface
+++ a/arch/ia64/mm/init.c
@@ -722,7 +722,17 @@ int arch_add_memory(int nid, u64 start, 
 
 int remove_memory(u64 start, u64 size)
 {
-	return -EINVAL;
+	unsigned long start_pfn, end_pfn;
+	unsigned long timeout = 120 * HZ;
+	int ret;
+	start_pfn = start >> PAGE_SHIFT;
+	end_pfn = start_pfn + (size >> PAGE_SHIFT);
+	ret = offline_pages(start_pfn, end_pfn, timeout);
+	if (ret)
+		goto out;
+	/* we can free mem_map at this point */
+out:
+	return ret;
 }
 EXPORT_SYMBOL_GPL(remove_memory);
 #endif
_