aboutsummaryrefslogtreecommitdiff
diff options
context:
space:
mode:
Diffstat
-rw-r--r--include/sound/core.h3
-rw-r--r--sound/core/control.c3
-rw-r--r--sound/core/hwdep.c5
-rw-r--r--sound/core/init.c50
-rw-r--r--sound/core/oss/mixer_oss.c10
-rw-r--r--sound/core/oss/pcm_oss.c2
-rw-r--r--sound/core/pcm_native.c9
-rw-r--r--sound/core/rawmidi.c6
-rw-r--r--sound/core/sound.c11
-rw-r--r--sound/core/sound_oss.c10
10 files changed, 79 insertions, 30 deletions
diff --git a/include/sound/core.h b/include/sound/core.h
index 1fa2407c966..78c5b4e1e8e 100644
--- a/include/sound/core.h
+++ b/include/sound/core.h
@@ -132,6 +132,7 @@ struct snd_card {
int shutdown; /* this card is going down */
int free_on_last_close; /* free in context of file_release */
wait_queue_head_t shutdown_sleep;
+ atomic_t refcount; /* refcount for disconnection */
struct device *dev; /* device assigned to this card */
struct device *card_dev; /* cardX object for sysfs */
@@ -189,6 +190,7 @@ struct snd_minor {
const struct file_operations *f_ops; /* file operations */
void *private_data; /* private data for f_ops->open */
struct device *dev; /* device for sysfs */
+ struct snd_card *card_ptr; /* assigned card instance */
};
/* return a device pointer linked to each sound device as a parent */
@@ -295,6 +297,7 @@ int snd_card_info_done(void);
int snd_component_add(struct snd_card *card, const char *component);
int snd_card_file_add(struct snd_card *card, struct file *file);
int snd_card_file_remove(struct snd_card *card, struct file *file);
+void snd_card_unref(struct snd_card *card);
#define snd_card_set_dev(card, devptr) ((card)->dev = (devptr))
diff --git a/sound/core/control.c b/sound/core/control.c
index f8c5be46451..520a556d28c 100644
--- a/sound/core/control.c
+++ b/sound/core/control.c
@@ -85,6 +85,7 @@ static int snd_ctl_open(struct inode *inode, struct file *file)
write_lock_irqsave(&card->ctl_files_rwlock, flags);
list_add_tail(&ctl->list, &card->ctl_files);
write_unlock_irqrestore(&card->ctl_files_rwlock, flags);
+ snd_card_unref(card);
return 0;
__error:
@@ -92,6 +93,8 @@ static int snd_ctl_open(struct inode *inode, struct file *file)
__error2:
snd_card_file_remove(card, file);
__error1:
+ if (card)
+ snd_card_unref(card);
return err;
}
diff --git a/sound/core/hwdep.c b/sound/core/hwdep.c
index a70ee7f1ed9..dbc3556bae3 100644
--- a/sound/core/hwdep.c
+++ b/sound/core/hwdep.c
@@ -99,8 +99,10 @@ static int snd_hwdep_open(struct inode *inode, struct file * file)
if (hw == NULL)
return -ENODEV;
- if (!try_module_get(hw->card->module))
+ if (!try_module_get(hw->card->module)) {
+ snd_card_unref(hw->card);
return -EFAULT;
+ }
init_waitqueue_entry(&wait, current);
add_wait_queue(&hw->open_wait, &wait);
@@ -147,6 +149,7 @@ static int snd_hwdep_open(struct inode *inode, struct file * file)
mutex_unlock(&hw->open_mutex);
if (err < 0)
module_put(hw->card->module);
+ snd_card_unref(hw->card);
return err;
}
diff --git a/sound/core/init.c b/sound/core/init.c
index 2c041bb36ab..4c3c589b4d2 100644
--- a/sound/core/init.c
+++ b/sound/core/init.c
@@ -211,6 +211,7 @@ int snd_card_create(int idx, const char *xid,
spin_lock_init(&card->files_lock);
INIT_LIST_HEAD(&card->files_list);
init_waitqueue_head(&card->shutdown_sleep);
+ atomic_set(&card->refcount, 0);
#ifdef CONFIG_PM
mutex_init(&card->power_lock);
init_waitqueue_head(&card->power_sleep);
@@ -444,21 +445,36 @@ static int snd_card_do_free(struct snd_card *card)
return 0;
}
+/**
+ * snd_card_unref - release the reference counter
+ * @card: the card instance
+ *
+ * Decrements the reference counter. When it reaches to zero, wake up
+ * the sleeper and call the destructor if needed.
+ */
+void snd_card_unref(struct snd_card *card)
+{
+ if (atomic_dec_and_test(&card->refcount)) {
+ wake_up(&card->shutdown_sleep);
+ if (card->free_on_last_close)
+ snd_card_do_free(card);
+ }
+}
+EXPORT_SYMBOL(snd_card_unref);
+
int snd_card_free_when_closed(struct snd_card *card)
{
- int free_now = 0;
- int ret = snd_card_disconnect(card);
- if (ret)
- return ret;
+ int ret;
- spin_lock(&card->files_lock);
- if (list_empty(&card->files_list))
- free_now = 1;
- else
- card->free_on_last_close = 1;
- spin_unlock(&card->files_lock);
+ atomic_inc(&card->refcount);
+ ret = snd_card_disconnect(card);
+ if (ret) {
+ atomic_dec(&card->refcount);
+ return ret;
+ }
- if (free_now)
+ card->free_on_last_close = 1;
+ if (atomic_dec_and_test(&card->refcount))
snd_card_do_free(card);
return 0;
}
@@ -472,7 +488,7 @@ int snd_card_free(struct snd_card *card)
return ret;
/* wait, until all devices are ready for the free operation */
- wait_event(card->shutdown_sleep, list_empty(&card->files_list));
+ wait_event(card->shutdown_sleep, !atomic_read(&card->refcount));
snd_card_do_free(card);
return 0;
}
@@ -853,6 +869,7 @@ int snd_card_file_add(struct snd_card *card, struct file *file)
return -ENODEV;
}
list_add(&mfile->list, &card->files_list);
+ atomic_inc(&card->refcount);
spin_unlock(&card->files_lock);
return 0;
}
@@ -875,7 +892,6 @@ EXPORT_SYMBOL(snd_card_file_add);
int snd_card_file_remove(struct snd_card *card, struct file *file)
{
struct snd_monitor_file *mfile, *found = NULL;
- int last_close = 0;
spin_lock(&card->files_lock);
list_for_each_entry(mfile, &card->files_list, list) {
@@ -890,19 +906,13 @@ int snd_card_file_remove(struct snd_card *card, struct file *file)
break;
}
}
- if (list_empty(&card->files_list))
- last_close = 1;
spin_unlock(&card->files_lock);
- if (last_close) {
- wake_up(&card->shutdown_sleep);
- if (card->free_on_last_close)
- snd_card_do_free(card);
- }
if (!found) {
snd_printk(KERN_ERR "ALSA card file remove problem (%p)\n", file);
return -ENOENT;
}
kfree(found);
+ snd_card_unref(card);
return 0;
}
diff --git a/sound/core/oss/mixer_oss.c b/sound/core/oss/mixer_oss.c
index d8359cfeca1..5cdd0fe7109 100644
--- a/sound/core/oss/mixer_oss.c
+++ b/sound/core/oss/mixer_oss.c
@@ -51,14 +51,19 @@ static int snd_mixer_oss_open(struct inode *inode, struct file *file)
SNDRV_OSS_DEVICE_TYPE_MIXER);
if (card == NULL)
return -ENODEV;
- if (card->mixer_oss == NULL)
+ if (card->mixer_oss == NULL) {
+ snd_card_unref(card);
return -ENODEV;
+ }
err = snd_card_file_add(card, file);
- if (err < 0)
+ if (err < 0) {
+ snd_card_unref(card);
return err;
+ }
fmixer = kzalloc(sizeof(*fmixer), GFP_KERNEL);
if (fmixer == NULL) {
snd_card_file_remove(card, file);
+ snd_card_unref(card);
return -ENOMEM;
}
fmixer->card = card;
@@ -67,6 +72,7 @@ static int snd_mixer_oss_open(struct inode *inode, struct file *file)
if (!try_module_get(card->module)) {
kfree(fmixer);
snd_card_file_remove(card, file);
+ snd_card_unref(card);
return -EFAULT;
}
return 0;
diff --git a/sound/core/oss/pcm_oss.c b/sound/core/oss/pcm_oss.c
index 23c34a02894..ef6414b35ac 100644
--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -2457,6 +2457,8 @@ static int snd_pcm_oss_open(struct inode *inode, struct file *file)
__error2:
snd_card_file_remove(pcm->card, file);
__error1:
+ if (pcm)
+ snd_card_unref(pcm->card);
return err;
}
diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index a6380787b7f..4a3a5c03131 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1627,6 +1627,7 @@ static int snd_pcm_link(struct snd_pcm_substream *substream, int fd)
_end:
write_unlock_irq(&snd_pcm_link_rwlock);
up_write(&snd_pcm_link_rwsem);
+ snd_card_unref(substream1->pcm->card);
fput(file);
return res;
}
@@ -2104,7 +2105,9 @@ static int snd_pcm_playback_open(struct inode *inode, struct file *file)
return err;
pcm = snd_lookup_minor_data(iminor(inode),
SNDRV_DEVICE_TYPE_PCM_PLAYBACK);
- return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
+ err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_PLAYBACK);
+ snd_card_unref(pcm->card);
+ return err;
}
static int snd_pcm_capture_open(struct inode *inode, struct file *file)
@@ -2115,7 +2118,9 @@ static int snd_pcm_capture_open(struct inode *inode, struct file *file)
return err;
pcm = snd_lookup_minor_data(iminor(inode),
SNDRV_DEVICE_TYPE_PCM_CAPTURE);
- return snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
+ err = snd_pcm_open(file, pcm, SNDRV_PCM_STREAM_CAPTURE);
+ snd_card_unref(pcm->card);
+ return err;
}
static int snd_pcm_open(struct file *file, struct snd_pcm *pcm, int stream)
diff --git a/sound/core/rawmidi.c b/sound/core/rawmidi.c
index cbbed0db9e5..69935c08d31 100644
--- a/sound/core/rawmidi.c
+++ b/sound/core/rawmidi.c
@@ -394,8 +394,10 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
if (rmidi == NULL)
return -ENODEV;
- if (!try_module_get(rmidi->card->module))
+ if (!try_module_get(rmidi->card->module)) {
+ snd_card_unref(rmidi->card);
return -ENXIO;
+ }
mutex_lock(&rmidi->open_mutex);
card = rmidi->card;
@@ -455,6 +457,7 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
#endif
file->private_data = rawmidi_file;
mutex_unlock(&rmidi->open_mutex);
+ snd_card_unref(rmidi->card);
return 0;
__error:
@@ -462,6 +465,7 @@ static int snd_rawmidi_open(struct inode *inode, struct file *file)
__error_card:
mutex_unlock(&rmidi->open_mutex);
module_put(rmidi->card->module);
+ snd_card_unref(rmidi->card);
return err;
}
diff --git a/sound/core/sound.c b/sound/core/sound.c
index 1c7a3efe177..b235aaa3a1b 100644
--- a/sound/core/sound.c
+++ b/sound/core/sound.c
@@ -99,6 +99,10 @@ static void snd_request_other(int minor)
*
* Checks that a minor device with the specified type is registered, and returns
* its user data pointer.
+ *
+ * This function increments the reference counter of the card instance
+ * if an associated instance with the given minor number and type is found.
+ * The caller must call snd_card_unref() appropriately later.
*/
void *snd_lookup_minor_data(unsigned int minor, int type)
{
@@ -109,9 +113,11 @@ void *snd_lookup_minor_data(unsigned int minor, int type)
return NULL;
mutex_lock(&sound_mutex);
mreg = snd_minors[minor];
- if (mreg && mreg->type == type)
+ if (mreg && mreg->type == type) {
private_data = mreg->private_data;
- else
+ if (mreg->card_ptr)
+ atomic_inc(&mreg->card_ptr->refcount);
+ } else
private_data = NULL;
mutex_unlock(&sound_mutex);
return private_data;
@@ -275,6 +281,7 @@ int snd_register_device_for_dev(int type, struct snd_card *card, int dev,
preg->device = dev;
preg->f_ops = f_ops;
preg->private_data = private_data;
+ preg->card_ptr = card;
mutex_lock(&sound_mutex);
#ifdef CONFIG_SND_DYNAMIC_MINORS
minor = snd_find_free_minor(type);
diff --git a/sound/core/sound_oss.c b/sound/core/sound_oss.c
index 0c164e5e432..cdeae29f43f 100644
--- a/sound/core/sound_oss.c
+++ b/sound/core/sound_oss.c
@@ -39,6 +39,9 @@
static struct snd_minor *snd_oss_minors[SNDRV_OSS_MINORS];
static DEFINE_MUTEX(sound_oss_mutex);
+/* NOTE: This function increments the refcount of the associated card like
+ * snd_lookup_minor_data(); the caller must call snd_card_unref() appropriately
+ */
void *snd_lookup_oss_minor_data(unsigned int minor, int type)
{
struct snd_minor *mreg;
@@ -48,9 +51,11 @@ void *snd_lookup_oss_minor_data(unsigned int minor, int type)
return NULL;
mutex_lock(&sound_oss_mutex);
mreg = snd_oss_minors[minor];
- if (mreg && mreg->type == type)
+ if (mreg && mreg->type == type) {
private_data = mreg->private_data;
- else
+ if (mreg->card_ptr)
+ atomic_inc(&mreg->card_ptr->refcount);
+ } else
private_data = NULL;
mutex_unlock(&sound_oss_mutex);
return private_data;
@@ -122,6 +127,7 @@ int snd_register_oss_device(int type, struct snd_card *card, int dev,
preg->device = dev;
preg->f_ops = f_ops;
preg->private_data = private_data;
+ preg->card_ptr = card;
mutex_lock(&sound_oss_mutex);
snd_oss_minors[minor] = preg;
minor_unit = SNDRV_MINOR_OSS_DEVICE(minor);
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-20 06:44:53 +0000