diff --git a/drivers/md/bitmap.h b/drivers/md/bitmap.h
index 162ab09..2668926 100644
--- a/drivers/md/bitmap.h
+++ b/drivers/md/bitmap.h
@@ -197,7 +197,7 @@
 		unsigned long *filemap_attr;	/* attributes associated
 						 * w/ filemap pages */
 		unsigned long file_pages;	/* number of pages in the file*/
-		int last_page_size;		/* bytes in the last page */
+		unsigned long bytes;		/* total bytes in the bitmap */
 	} storage;
 
 	unsigned long flags;