diff --git a/include/common/compiler.h b/include/common/compiler.h
index 1347b6236..3e66709f9 100644
--- a/include/common/compiler.h
+++ b/include/common/compiler.h
@@ -89,6 +89,7 @@
 #define round_down(x, y)   ((x) & ~__round_mask(x, y))
 #define DIV_ROUND_UP(n, d) (((n) + (d)-1) / (d))
 #define ALIGN(x, a)	   (((x) + (a)-1) & ~((a)-1))
+#define ALIGN_DOWN(x, a)   ALIGN((x) - ((a) - 1), (a))
 
 #define min(x, y)                              \
 	({                                     \