From b95bd3a454cf9e9e111b6b87c02550368fe6e802 Mon Sep 17 00:00:00 2001 From: Takashi Iwai Date: Fri, 20 Feb 2015 16:49:04 +0100 Subject: ALSA: pcm: Don't add internal PCMs to PCM device list An internal PCM object shouldn't be added to the PCM device list, as it's never accessed directly from the user-space, and it has no proc or any similar accesses. Currently, it's excluded in snd_pcm_get() and snd_pcm_next(), but it's easier not to add such an object to the list. Actually, the whole snd_pcm_dev_register() can be skipped for an internal PCM. So this patch changes the code there, but also addresses the uninitialized list_head access. Acked-by: Liam Girdwood Signed-off-by: Takashi Iwai --- sound/core/pcm.c | 31 ++++++++++++++++--------------- 1 file changed, 16 insertions(+), 15 deletions(-) diff --git a/sound/core/pcm.c b/sound/core/pcm.c index d63d262c571e..d440629e08e2 100644 --- a/sound/core/pcm.c +++ b/sound/core/pcm.c @@ -49,8 +49,6 @@ static struct snd_pcm *snd_pcm_get(struct snd_card *card, int device) struct snd_pcm *pcm; list_for_each_entry(pcm, &snd_pcm_devices, list) { - if (pcm->internal) - continue; if (pcm->card == card && pcm->device == device) return pcm; } @@ -62,8 +60,6 @@ static int snd_pcm_next(struct snd_card *card, int device) struct snd_pcm *pcm; list_for_each_entry(pcm, &snd_pcm_devices, list) { - if (pcm->internal) - continue; if (pcm->card == card && pcm->device > device) return pcm->device; else if (pcm->card->number > card->number) @@ -76,6 +72,9 @@ static int snd_pcm_add(struct snd_pcm *newpcm) { struct snd_pcm *pcm; + if (newpcm->internal) + return 0; + list_for_each_entry(pcm, &snd_pcm_devices, list) { if (pcm->card == newpcm->card && pcm->device == newpcm->device) return -EBUSY; @@ -782,6 +781,9 @@ static int _snd_pcm_new(struct snd_card *card, const char *id, int device, pcm->card = card; pcm->device = device; pcm->internal = internal; + mutex_init(&pcm->open_mutex); + init_waitqueue_head(&pcm->open_wait); + INIT_LIST_HEAD(&pcm->list); if (id) strlcpy(pcm->id, id, sizeof(pcm->id)); if ((err = snd_pcm_new_stream(pcm, SNDRV_PCM_STREAM_PLAYBACK, playback_count)) < 0) { @@ -792,8 +794,6 @@ static int _snd_pcm_new(struct snd_card *card, const char *id, int device, snd_pcm_free(pcm); return err; } - mutex_init(&pcm->open_mutex); - init_waitqueue_head(&pcm->open_wait); if ((err = snd_device_new(card, SNDRV_DEV_PCM, pcm, &ops)) < 0) { snd_pcm_free(pcm); return err; @@ -1075,15 +1075,16 @@ static int snd_pcm_dev_register(struct snd_device *device) if (snd_BUG_ON(!device || !device->device_data)) return -ENXIO; pcm = device->device_data; + if (pcm->internal) + return 0; + mutex_lock(®ister_mutex); err = snd_pcm_add(pcm); - if (err) { - mutex_unlock(®ister_mutex); - return err; - } + if (err) + goto unlock; for (cidx = 0; cidx < 2; cidx++) { int devtype = -1; - if (pcm->streams[cidx].substream == NULL || pcm->internal) + if (pcm->streams[cidx].substream == NULL) continue; switch (cidx) { case SNDRV_PCM_STREAM_PLAYBACK: @@ -1098,9 +1099,8 @@ static int snd_pcm_dev_register(struct snd_device *device) &snd_pcm_f_ops[cidx], pcm, &pcm->streams[cidx].dev); if (err < 0) { - list_del(&pcm->list); - mutex_unlock(®ister_mutex); - return err; + list_del_init(&pcm->list); + goto unlock; } for (substream = pcm->streams[cidx].substream; substream; substream = substream->next) @@ -1110,8 +1110,9 @@ static int snd_pcm_dev_register(struct snd_device *device) list_for_each_entry(notify, &snd_pcm_notify_list, list) notify->n_register(pcm); + unlock: mutex_unlock(®ister_mutex); - return 0; + return err; } static int snd_pcm_dev_disconnect(struct snd_device *device) -- cgit v1.2.3