diff --git a/include/linux/libata.h b/include/linux/libata.h
index 3198617..9b6ba19 100644
--- a/include/linux/libata.h
+++ b/include/linux/libata.h
@@ -555,6 +555,10 @@
 	u8			device;
 
 	u8			command;	/* IO operation */
+
+	u32			auxiliary;	/* auxiliary field */
+						/* from SATA 3.1 and */
+						/* ATA-8 ACS-3 */
 };
 
 #ifdef CONFIG_ATA_SFF