From: mglocker <mglocker@openbsd.org>
Date: Wed, 23 Jul 2008 22:10:21 +0000 (+0000)
Subject: If /dev/video* is already used by an application, return EBUSY to other
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=2f7891056916b2b6c182c47a4d9ce1a5e33cd307;p=openbsd

If /dev/video* is already used by an application, return EBUSY to other
applications.  Fixes a kernel panic.

Reported by ian@
---

diff --git a/sys/dev/video.c b/sys/dev/video.c
index 57d69a2847c..cfa33d97126 100644
--- a/sys/dev/video.c
+++ b/sys/dev/video.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: video.c,v 1.17 2008/07/19 06:39:00 mglocker Exp $	*/
+/*	$OpenBSD: video.c,v 1.18 2008/07/23 22:10:21 mglocker Exp $	*/
 /*
  * Copyright (c) 2008 Robert Nagy <robert@openbsd.org>
  * Copyright (c) 2008 Marcus Glocker <mglocker@openbsd.org>
@@ -97,6 +97,10 @@ videoopen(dev_t dev, int flags, int fmt, struct proc *p)
 	     sc->hw_if == NULL)
 		return (ENXIO);
 
+	if (sc->sc_open & VIDEO_OPEN)
+		return (EBUSY);
+	sc->sc_open |= VIDEO_OPEN;
+
 	sc->sc_start_read = 0;
 
 	if (sc->hw_if->open != NULL)
@@ -110,13 +114,16 @@ int
 videoclose(dev_t dev, int flags, int fmt, struct proc *p)
 {
 	struct video_softc *sc;
+	int r = 0;
 
 	sc = video_cd.cd_devs[VIDEOUNIT(dev)];
 
 	if (sc->hw_if->close != NULL)
-		return (sc->hw_if->close(sc->hw_hdl));
-	else
-		return (0);
+		r = sc->hw_if->close(sc->hw_hdl);
+
+	sc->sc_open &= ~VIDEO_OPEN;
+
+	return (r);
 }
 
 int
diff --git a/sys/dev/videovar.h b/sys/dev/videovar.h
index 8625a5181e4..678a6da1e35 100644
--- a/sys/dev/videovar.h
+++ b/sys/dev/videovar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: videovar.h,v 1.5 2008/06/13 05:00:32 mglocker Exp $	*/
+/*	$OpenBSD: videovar.h,v 1.6 2008/07/23 22:10:21 mglocker Exp $	*/
 /*
  * Copyright (c) 2008 Robert Nagy <robert@openbsd.org>
  * Copyright (c) 2008 Marcus Glocker <mglocker@openbsd.org>
@@ -25,6 +25,8 @@ struct video_softc {
 	struct device		*sc_dev;	/* hardware device struct */
 	struct video_hw_if	*hw_if;		/* hardware interface */
 	char			 sc_dying;	/* device detached */
+#define VIDEO_OPEN	0x01
+	char			 sc_open;
 
 	int			 sc_fsize;
 	uint8_t			*sc_fbuffer;