diff --git a/mm/cma.h b/mm/cma.h
index 1132d733556d..17c75a4246c8 100644
--- a/mm/cma.h
+++ b/mm/cma.h
@@ -16,7 +16,7 @@ struct cma {
 extern struct cma cma_areas[MAX_CMA_AREAS];
 extern unsigned cma_area_count;
 
-static unsigned long cma_bitmap_maxno(struct cma *cma)
+static inline unsigned long cma_bitmap_maxno(struct cma *cma)
 {
 	return cma->count >> cma->order_per_bit;
 }