[ALSA] snd_usb_caiaq: fix potential lockups locking
This patch fixes potential lockups in snd_usb_caiaq by refining the
locking mechanims and by using usb_kill_urb() in favor to
usb_unlink_urb().
Signed-off-by: Daniel Mack <daniel@caiaq.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/usb/caiaq/caiaq-audio.c b/sound/usb/caiaq/caiaq-audio.c
index 9cc4cd8..1aa9279 100644
--- a/sound/usb/caiaq/caiaq-audio.c
+++ b/sound/usb/caiaq/caiaq-audio.c
@@ -1,5 +1,5 @@
/*
- * Copyright (c) 2006,2007 Daniel Mack, Karsten Wiese
+ * Copyright (c) 2006-2008 Daniel Mack, Karsten Wiese
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
@@ -77,10 +77,15 @@
deactivate_substream(struct snd_usb_caiaqdev *dev,
struct snd_pcm_substream *sub)
{
+ unsigned long flags;
+ spin_lock_irqsave(&dev->spinlock, flags);
+
if (sub->stream == SNDRV_PCM_STREAM_PLAYBACK)
dev->sub_playback[sub->number] = NULL;
else
dev->sub_capture[sub->number] = NULL;
+
+ spin_unlock_irqrestore(&dev->spinlock, flags);
}
static int
@@ -97,13 +102,13 @@
{
int i, ret;
- debug("stream_start(%p)\n", dev);
- spin_lock_irq(&dev->spinlock);
- if (dev->streaming) {
- spin_unlock_irq(&dev->spinlock);
- return -EINVAL;
- }
+ debug("%s(%p)\n", __func__, dev);
+ if (dev->streaming)
+ return -EINVAL;
+
+ memset(dev->sub_playback, 0, sizeof(dev->sub_playback));
+ memset(dev->sub_capture, 0, sizeof(dev->sub_capture));
dev->input_panic = 0;
dev->output_panic = 0;
dev->first_packet = 1;
@@ -112,37 +117,35 @@
for (i = 0; i < N_URBS; i++) {
ret = usb_submit_urb(dev->data_urbs_in[i], GFP_ATOMIC);
if (ret) {
- log("unable to trigger initial read #%d! (ret = %d)\n",
- i, ret);
+ log("unable to trigger read #%d! (ret %d)\n", i, ret);
dev->streaming = 0;
- spin_unlock_irq(&dev->spinlock);
return -EPIPE;
}
}
- spin_unlock_irq(&dev->spinlock);
return 0;
}
static void stream_stop(struct snd_usb_caiaqdev *dev)
{
int i;
-
- debug("stream_stop(%p)\n", dev);
+
+ debug("%s(%p)\n", __func__, dev);
if (!dev->streaming)
return;
dev->streaming = 0;
+
for (i = 0; i < N_URBS; i++) {
- usb_unlink_urb(dev->data_urbs_in[i]);
- usb_unlink_urb(dev->data_urbs_out[i]);
+ usb_kill_urb(dev->data_urbs_in[i]);
+ usb_kill_urb(dev->data_urbs_out[i]);
}
}
static int snd_usb_caiaq_substream_open(struct snd_pcm_substream *substream)
{
struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(substream);
- debug("snd_usb_caiaq_substream_open(%p)\n", substream);
+ debug("%s(%p)\n", __func__, substream);
substream->runtime->hw = dev->pcm_info;
snd_pcm_limit_hw_rates(substream->runtime);
return 0;
@@ -152,7 +155,7 @@
{
struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(substream);
- debug("snd_usb_caiaq_substream_close(%p)\n", substream);
+ debug("%s(%p)\n", __func__, substream);
if (all_substreams_zero(dev->sub_playback) &&
all_substreams_zero(dev->sub_capture)) {
/* when the last client has stopped streaming,
@@ -160,24 +163,22 @@
stream_stop(dev);
dev->pcm_info.rates = dev->samplerates;
}
-
+
return 0;
}
static int snd_usb_caiaq_pcm_hw_params(struct snd_pcm_substream *sub,
struct snd_pcm_hw_params *hw_params)
{
- debug("snd_usb_caiaq_pcm_hw_params(%p)\n", sub);
+ debug("%s(%p)\n", __func__, sub);
return snd_pcm_lib_malloc_pages(sub, params_buffer_bytes(hw_params));
}
static int snd_usb_caiaq_pcm_hw_free(struct snd_pcm_substream *sub)
{
struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(sub);
- debug("snd_usb_caiaq_pcm_hw_free(%p)\n", sub);
- spin_lock_irq(&dev->spinlock);
+ debug("%s(%p)\n", __func__, sub);
deactivate_substream(dev, sub);
- spin_unlock_irq(&dev->spinlock);
return snd_pcm_lib_free_pages(sub);
}
@@ -196,7 +197,7 @@
struct snd_usb_caiaqdev *dev = snd_pcm_substream_chip(substream);
struct snd_pcm_runtime *runtime = substream->runtime;
- debug("snd_usb_caiaq_pcm_prepare(%p)\n", substream);
+ debug("%s(%p)\n", __func__, substream);
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
dev->audio_out_buf_pos[index] = BYTES_PER_SAMPLE + 1;
@@ -247,15 +248,11 @@
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
- spin_lock(&dev->spinlock);
activate_substream(dev, sub);
- spin_unlock(&dev->spinlock);
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
- spin_lock(&dev->spinlock);
deactivate_substream(dev, sub);
- spin_unlock(&dev->spinlock);
break;
default:
return -EINVAL;
@@ -328,8 +325,6 @@
if (all_substreams_zero(dev->sub_capture))
return;
- spin_lock(&dev->spinlock);
-
for (i = 0; i < iso->actual_length;) {
for (stream = 0; stream < dev->n_streams; stream++, i++) {
sub = dev->sub_capture[stream];
@@ -345,8 +340,6 @@
}
}
}
-
- spin_unlock(&dev->spinlock);
}
static void read_in_urb_mode2(struct snd_usb_caiaqdev *dev,
@@ -358,8 +351,6 @@
struct snd_pcm_substream *sub;
int stream, i;
- spin_lock(&dev->spinlock);
-
for (i = 0; i < iso->actual_length;) {
if (i % (dev->n_streams * BYTES_PER_SAMPLE_USB) == 0) {
for (stream = 0;
@@ -393,8 +384,6 @@
}
}
}
-
- spin_unlock(&dev->spinlock);
}
static void read_in_urb(struct snd_usb_caiaqdev *dev,
@@ -418,8 +407,6 @@
dev->input_panic ? "(input)" : "",
dev->output_panic ? "(output)" : "");
}
-
- check_for_elapsed_periods(dev, dev->sub_capture);
}
static void fill_out_urb(struct snd_usb_caiaqdev *dev,
@@ -429,8 +416,6 @@
unsigned char *usb_buf = urb->transfer_buffer + iso->offset;
struct snd_pcm_substream *sub;
int stream, i;
-
- spin_lock(&dev->spinlock);
for (i = 0; i < iso->length;) {
for (stream = 0; stream < dev->n_streams; stream++, i++) {
@@ -456,9 +441,6 @@
for (stream = 0; stream < dev->n_streams; stream++, i++)
usb_buf[i] = MAKE_CHECKBYTE(dev, stream, i);
}
-
- spin_unlock(&dev->spinlock);
- check_for_elapsed_periods(dev, dev->sub_playback);
}
static void read_completed(struct urb *urb)
@@ -472,6 +454,7 @@
return;
dev = info->dev;
+
if (!dev->streaming)
return;
@@ -489,8 +472,12 @@
out->iso_frame_desc[outframe].offset = BYTES_PER_FRAME * frame;
if (len > 0) {
+ spin_lock(&dev->spinlock);
fill_out_urb(dev, out, &out->iso_frame_desc[outframe]);
read_in_urb(dev, urb, &urb->iso_frame_desc[frame]);
+ spin_unlock(&dev->spinlock);
+ check_for_elapsed_periods(dev, dev->sub_playback);
+ check_for_elapsed_periods(dev, dev->sub_capture);
send_it = 1;
}
@@ -696,7 +683,7 @@
void snd_usb_caiaq_audio_free(struct snd_usb_caiaqdev *dev)
{
- debug("snd_usb_caiaq_audio_free (%p)\n", dev);
+ debug("%s(%p)\n", __func__, dev);
stream_stop(dev);
free_urbs(dev->data_urbs_in);
free_urbs(dev->data_urbs_out);