diff --git a/linux-2.6-xen-sparse/drivers/xen/blkfront/vbd.c b/linux-2.6-xen-sparse/drivers/xen/blkfront/vbd.c
index 210bfa9105..87f046932b 100644
--- a/linux-2.6-xen-sparse/drivers/xen/blkfront/vbd.c
+++ b/linux-2.6-xen-sparse/drivers/xen/blkfront/vbd.c
@@ -137,7 +137,7 @@ static vdisk_t *xlvbd_probe(int *ret)
     blkif_control_probe_send(&req, &rsp,
                              (unsigned long)(virt_to_machine(buf)));
 #else
-    req.frame_and_sects[0] = blkif_fas(virt_to_machine(buf), 0, ((PAGE_SIZE/512)-1);
+    req.frame_and_sects[0] = blkif_fas(virt_to_machine(buf), 0, (PAGE_SIZE/512)-1);
 
     blkif_control_send(&req, &rsp);
 #endif
diff --git a/xen/include/public/io/blkif.h b/xen/include/public/io/blkif.h
index 45d4132e8b..1b10b70a3e 100644
--- a/xen/include/public/io/blkif.h
+++ b/xen/include/public/io/blkif.h
@@ -47,7 +47,7 @@ typedef struct blkif_request {
     unsigned long  frame_and_sects[BLKIF_MAX_SEGMENTS_PER_REQUEST];
 } blkif_request_t;
 
-#define blkif_fas(_addr, _fs, _ls) ((addr)|((_fs)<<5)|(_ls))
+#define blkif_fas(_addr, _fs, _ls) ((_addr)|((_fs)<<5)|(_ls))
 #define blkif_first_sect(_fas) (((_fas)>>5)&31)
 #define blkif_last_sect(_fas)  ((_fas)&31)