diff --git a/include/linux/swap.h b/include/linux/swap.h
index e89c5d0521c9..260dc51b1006 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -139,9 +139,9 @@ struct swap_extent {
 /*
  * Max bad pages in the new format..
  */
-#define __swapoffset(x) ((unsigned long)&((union swap_header *)0)->x)
 #define MAX_SWAP_BADPAGES \
-	((__swapoffset(magic.magic) - __swapoffset(info.badpages)) / sizeof(int))
+	((offsetof(union swap_header, magic.magic) - \
+	  offsetof(union swap_header, info.badpages)) / sizeof(int))
 
 enum {
 	SWP_USED	= (1 << 0),	/* is slot in swap_info[] used? */