fix a bug where opening for write would not fail if channel allocation failed

when playing, if we stall for 1s with no data advancing, abort and mark the
channel dead - fail all future operations

5 files changed, 30 insertions, 11 deletions

diff --git a/sys/dev/sound/pcm/channel.c b/sys/dev/sound/pcm/channel.c
index 45568be..9f81751 100644
--- a/sys/dev/sound/pcm/channel.c
+++ b/sys/dev/sound/pcm/channel.c
@@ -428,7 +428,7 @@ chn_wrintr(pcm_channel *c)
 int
 chn_write(pcm_channel *c, struct uio *buf)
 {
-	int 		ret = 0, timeout, res, newsize;
+	int 		ret = 0, timeout, res, newsize, count;
 	long		s;
 	snd_dbuf       *b = &c->buffer;
 	snd_dbuf       *bs = &c->buffer2nd;
@@ -460,9 +460,6 @@ chn_write(pcm_channel *c, struct uio *buf)
 		DEB(printf("pcm warning: frags reset to %d x %d\n", bs->blkcnt, bs->blksz));
 	}
 
-	/* Store the initial size in the uio. */
-	res = buf->uio_resid;
-
 	/*
 	 * Fill up the secondary and DMA buffer.
 	 * chn_wrfeed*() takes care of the alignment.
@@ -479,12 +476,18 @@ chn_write(pcm_channel *c, struct uio *buf)
 		chn_start(c);
 
 	if (ret == 0) {
+		count = hz;
 		/* Wait until all samples are played in blocking mode. */
-   		while (buf->uio_resid > 0) {
+   		while ((buf->uio_resid > 0) && (count > 0)) {
 			/* Check for underflow before writing into the buffers. */
 			chn_checkunderflow(c);
 			/* Fill up the buffers with new pcm data. */
+			res = buf->uio_resid;
   			while (chn_wrfeed2nd(c, buf) > 0);
+			if (buf->uio_resid < res)
+				count = hz;
+			else
+				count--;
 
 			/* Have we finished to feed the secondary buffer? */
 			if (buf->uio_resid == 0)
@@ -499,6 +502,10 @@ chn_write(pcm_channel *c, struct uio *buf)
  			if (ret == EINTR || ret == ERESTART)
 				break;
  		}
+		if (count == 0) {
+			c->flags |= CHN_F_DEAD;
+			device_printf(c->parent->dev, "play interrupt timeout, channel dead\n");
+		}
 	} else
 		ret = 0;
 	c->flags &= ~CHN_F_WRITING;
diff --git a/sys/dev/sound/pcm/channel.h b/sys/dev/sound/pcm/channel.h
index 0c13b65..23e31df 100644
--- a/sys/dev/sound/pcm/channel.h
+++ b/sys/dev/sound/pcm/channel.h
@@ -81,9 +81,10 @@ extern pcm_feeder feeder_root;
 #define CHN_F_NBIO              0x00004000  /* do non-blocking i/o */
 #define CHN_F_INIT              0x00008000  /* changed parameters. need init */
 #define CHN_F_MAPPED		0x00010000  /* has been mmap()ed */
+#define CHN_F_DEAD		0x00020000
 
 
-#define CHN_F_RESET		(CHN_F_BUSY)
+#define CHN_F_RESET		(CHN_F_BUSY | CHN_F_DEAD)
 
 /*
  * This should be large enough to hold all pcm data between
diff --git a/sys/dev/sound/pcm/datatypes.h b/sys/dev/sound/pcm/datatypes.h
index 67e1923..31df62b 100644
--- a/sys/dev/sound/pcm/datatypes.h
+++ b/sys/dev/sound/pcm/datatypes.h
@@ -121,6 +121,7 @@ struct _pcm_channel {
 
 	int direction;
 	snd_dbuf buffer, buffer2nd;
+	snddev_info *parent;
 	void *devinfo;
 };
 
@@ -136,6 +137,7 @@ struct _snddev_info {
 	unsigned flags;
 	void *devinfo;
 	pcm_swap_t *swap;
+	device_t dev;
 	char status[SND_STATUSLEN];
 };
 
diff --git a/sys/dev/sound/pcm/dsp.c b/sys/dev/sound/pcm/dsp.c
index 6dfae6a..903de31 100644
--- a/sys/dev/sound/pcm/dsp.c
+++ b/sys/dev/sound/pcm/dsp.c
@@ -41,7 +41,7 @@ allocchn(snddev_info *d, int direction)
 	pcm_channel *chns = (direction == PCMDIR_PLAY)? d->play : d->rec;
 	int i, cnt = (direction == PCMDIR_PLAY)? d->playcount : d->reccount;
 	for (i = 0; i < cnt; i++) {
-		if (!(chns[i].flags & CHN_F_BUSY)) {
+		if (!(chns[i].flags & (CHN_F_BUSY | CHN_F_DEAD))) {
 			chns[i].flags |= CHN_F_BUSY;
 			return &chns[i];
 		}
@@ -94,8 +94,9 @@ dsp_open(snddev_info *d, int chan, int oflags, int devtype)
 	if (oflags & FWRITE) {
 		if (wrch == NULL) {
 			wrch = allocchn(d, PCMDIR_PLAY);
-			if (!wrch && (oflags & FREAD)) {
-				rdch->flags &= ~CHN_F_BUSY;
+			if (!wrch) {
+				if (rdch && (oflags & FREAD))
+					rdch->flags &= ~CHN_F_BUSY;
 				return EBUSY;
 			}
 		} else return EBUSY;
@@ -171,7 +172,7 @@ dsp_read(snddev_info *d, int chan, struct uio *buf, int flag)
 	getchns(d, chan, &rdch, &wrch);
 	KASSERT(rdch, ("dsp_read: nonexistant channel"));
 	KASSERT(rdch->flags & CHN_F_BUSY, ("dsp_read: nonbusy channel"));
-	if (rdch->flags & CHN_F_MAPPED) return EINVAL;
+	if (rdch->flags & (CHN_F_MAPPED | CHN_F_DEAD)) return EINVAL;
 	if (!(rdch->flags & CHN_F_RUNNING))
 		rdch->flags |= CHN_F_RUNNING;
 	return chn_read(rdch, buf);
@@ -187,7 +188,7 @@ dsp_write(snddev_info *d, int chan, struct uio *buf, int flag)
 	getchns(d, chan, &rdch, &wrch);
 	KASSERT(wrch, ("dsp_write: nonexistant channel"));
 	KASSERT(wrch->flags & CHN_F_BUSY, ("dsp_write: nonbusy channel"));
-	if (wrch->flags & CHN_F_MAPPED) return EINVAL;
+	if (wrch->flags & (CHN_F_MAPPED | CHN_F_DEAD)) return EINVAL;
 	if (!(wrch->flags & CHN_F_RUNNING))
 		wrch->flags |= CHN_F_RUNNING;
 	return chn_write(wrch, buf);
@@ -203,6 +204,12 @@ dsp_ioctl(snddev_info *d, int chan, u_long cmd, caddr_t arg)
 	rdch = d->arec[chan];
 	wrch = d->aplay[chan];
 
+	if (rdch && (rdch->flags & CHN_F_DEAD))
+		rdch = NULL;
+	if (wrch && (wrch->flags & CHN_F_DEAD))
+		wrch = NULL;
+	if (!(rdch || wrch))
+		return EINVAL;
     	/*
      	 * all routines are called with int. blocked. Make sure that
      	 * ints are re-enabled when calling slow or blocking functions!
diff --git a/sys/dev/sound/pcm/sound.c b/sys/dev/sound/pcm/sound.c
index 0d3a84c..c5c0b6d 100644
--- a/sys/dev/sound/pcm/sound.c
+++ b/sys/dev/sound/pcm/sound.c
@@ -106,6 +106,7 @@ pcm_addchan(device_t dev, int dir, pcm_channel *templ, void *devinfo)
 	}
 	ch = (dir == PCMDIR_PLAY)? &d->play[d->playcount] : &d->rec[d->reccount];
 	*ch = *templ;
+	ch->parent = d;
 	if (chn_init(ch, devinfo, dir)) {
 		device_printf(dev, "chn_init() for %s:%d failed\n",
 		              (dir == PCMDIR_PLAY)? "play" : "record",
@@ -174,6 +175,7 @@ pcm_register(device_t dev, void *devinfo, int numplay, int numrec)
 	make_dev(&snd_cdevsw, PCMMKMINOR(unit, SND_DEV_CTL, 0),
 		 UID_ROOT, GID_WHEEL, 0666, "mixer%d", unit);
 
+	d->dev = dev;
 	d->devinfo = devinfo;
 	d->chancount = d->playcount = d->reccount = 0;
     	sz = (numplay + numrec) * sizeof(pcm_channel *);