mm: thp: calculate the mapcount correctly for THP pages during WP faults

[karo-tx-linux.git] / include / linux / mm.h

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 864d7221de846e44e600245eaac773ab7116bcca..8f468e0d2534eddaa178fdf252e7cf4e53f3330b 100644 (file)
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -500,11 +500,20 @@ static inline int page_mapcount(struct page *page)
 
 #ifdef CONFIG_TRANSPARENT_HUGEPAGE
 int total_mapcount(struct page *page);
+int page_trans_huge_mapcount(struct page *page, int *total_mapcount);
 #else
 static inline int total_mapcount(struct page *page)
 {
        return page_mapcount(page);
 }
+static inline int page_trans_huge_mapcount(struct page *page,
+                                          int *total_mapcount)
+{
+       int mapcount = page_mapcount(page);
+       if (total_mapcount)
+               *total_mapcount = mapcount;
+       return mapcount;
+}
 #endif
 
 static inline struct page *virt_to_head_page(const void *x)