diff --git a/include/linux/page-isolation.h b/include/linux/page-isolation.h
index 2dc1e1697b451ce678781a55776a15c8934be7a5..047d64706f2a298157cf0d54305aa8e49f6f7837 100644
--- a/include/linux/page-isolation.h
+++ b/include/linux/page-isolation.h
@@ -65,11 +65,6 @@ undo_isolate_page_range(unsigned long start_pfn, unsigned long end_pfn,
 int test_pages_isolated(unsigned long start_pfn, unsigned long end_pfn,
 			bool skip_hwpoisoned_pages);
 
-/*
- * Internal functions. Changes pageblock's migrate type.
- */
-int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages);
-void unset_migratetype_isolate(struct page *page, unsigned migratetype);
 struct page *alloc_migrate_target(struct page *page, unsigned long private,
 				int **resultp);
 
diff --git a/mm/page_isolation.c b/mm/page_isolation.c
index 32fdc1df05e5f08469bfea30435a37c2db347f6b..4568fd58f70a02c472e525528db58eeb20c06ebf 100644
--- a/mm/page_isolation.c
+++ b/mm/page_isolation.c
@@ -9,7 +9,8 @@
 #include <linux/hugetlb.h>
 #include "internal.h"
 
-int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages)
+static int set_migratetype_isolate(struct page *page,
+				bool skip_hwpoisoned_pages)
 {
 	struct zone *zone;
 	unsigned long flags, pfn;
@@ -72,7 +73,7 @@ int set_migratetype_isolate(struct page *page, bool skip_hwpoisoned_pages)
 	return ret;
 }
 
-void unset_migratetype_isolate(struct page *page, unsigned migratetype)
+static void unset_migratetype_isolate(struct page *page, unsigned migratetype)
 {
 	struct zone *zone;
 	unsigned long flags, nr_pages;