diff --git a/block/qed.h b/block/qed.h
index abed147..62624a1 100644
--- a/block/qed.h
+++ b/block/qed.h
@@ -125,6 +125,7 @@
 
 enum {
     QED_AIOCB_WRITE = 0x0001,       /* read or write? */
+    QED_AIOCB_ZERO  = 0x0002,       /* zero write, used with QED_AIOCB_WRITE */
 };
 
 typedef struct QEDAIOCB {