diff --git a/include/linux/mm.h b/include/linux/mm.h
index 9c2695b..ce97a2b 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -450,6 +450,20 @@
 	return (unsigned long)page[1].lru.prev;
 }
 
+static inline int compound_trans_order(struct page *page)
+{
+	int order;
+	unsigned long flags;
+
+	if (!PageHead(page))
+		return 0;
+
+	flags = compound_lock_irqsave(page);
+	order = compound_order(page);
+	compound_unlock_irqrestore(page, flags);
+	return order;
+}
+
 static inline void set_compound_order(struct page *page, unsigned long order)
 {
 	page[1].lru.prev = (void *)order;