From: krw <krw@openbsd.org>
Date: Wed, 28 Jul 2010 23:47:43 +0000 (+0000)
Subject: DVD_INVALIDATE_AGID is a 'no payload' operation, so don't set
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=ffe9f3d7bc9f68579d8ed093f2caed73a36e6c1a;p=openbsd

DVD_INVALIDATE_AGID is a 'no payload' operation, so don't set
xs->datalen and reset xs->data to NULL. This prevents a spurious
attempt to setup (dma map, etc) and possibly attempt data tranfser.

In line with what Linux and FreeBSD do as far as I can tell.

Reduces the delay before my DVD starts playing its movie.

Idea to also set xs->data to NULL from matthew@.

"No objection" matthew@
---

diff --git a/sys/scsi/cd.c b/sys/scsi/cd.c
index 790ae7e360f..2f599259537 100644
--- a/sys/scsi/cd.c
+++ b/sys/scsi/cd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cd.c,v 1.180 2010/07/25 16:34:41 krw Exp $	*/
+/*	$OpenBSD: cd.c,v 1.181 2010/07/28 23:47:43 krw Exp $	*/
 /*	$NetBSD: cd.c,v 1.100 1997/04/02 02:29:30 mycroft Exp $	*/
 
 /*
@@ -1835,7 +1835,7 @@ dvd_auth(struct cd_softc *sc, union dvd_authinfo *a)
 	case DVD_INVALIDATE_AGID:
 		xs->cmd->opcode = GPCMD_REPORT_KEY;
 		xs->cmd->bytes[9] = 0x3f | (a->lsa.agid << 6);
-		xs->datalen = 16;
+		xs->data = NULL;
 
 		error = scsi_xs_sync(xs);
 		scsi_xs_put(xs);