diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index d17032c..08df1ea 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -215,8 +215,9 @@
 	/*
 	 * when request is used as a packet command carrier
 	 */
-	unsigned int cmd_len;
-	unsigned char cmd[BLK_MAX_CDB];
+	unsigned short cmd_len;
+	unsigned char __cmd[BLK_MAX_CDB];
+	unsigned char *cmd;
 
 	unsigned int data_len;
 	unsigned int extra_len;	/* length of alignment and padding */