ALSA: Use standard device refcount for card accounting

Drop the own refcount but use the standard device refcounting via
get_device() and put_device().  Introduce a new completion to snd_card
instead of the wait queue for syncing the last release, which is used
in snd_card_free().

Signed-off-by: Takashi Iwai <tiwai@suse.de>
This commit is contained in:
Takashi Iwai 2014-01-29 12:13:43 +01:00
parent 34356dbdb6
commit f246406481
4 changed files with 25 additions and 49 deletions

View File

@ -42,6 +42,7 @@
/* forward declarations */
struct pci_dev;
struct module;
struct completion;
/* device allocation stuff */
@ -130,9 +131,7 @@ struct snd_card {
state */
spinlock_t files_lock; /* lock the files for this 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 completion *release_completion;
struct device *dev; /* device assigned to this card */
struct device card_dev; /* cardX object for sysfs */
bool registered; /* card_dev is registered? */
@ -306,7 +305,7 @@ 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_unref(card) put_device(&(card)->card_dev)
#define snd_card_set_dev(card, devptr) ((card)->dev = (devptr))

View File

@ -28,6 +28,7 @@
#include <linux/time.h>
#include <linux/ctype.h>
#include <linux/pm.h>
#include <linux/completion.h>
#include <sound/core.h>
#include <sound/control.h>
@ -235,8 +236,6 @@ int snd_card_new(struct device *parent, int idx, const char *xid,
INIT_LIST_HEAD(&card->ctl_files);
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);
@ -474,58 +473,36 @@ static int snd_card_do_free(struct snd_card *card)
snd_printk(KERN_WARNING "unable to free card info\n");
/* Not fatal error */
}
if (card->release_completion)
complete(card->release_completion);
kfree(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)
put_device(&card->card_dev);
}
}
EXPORT_SYMBOL(snd_card_unref);
int snd_card_free_when_closed(struct snd_card *card)
{
int ret;
atomic_inc(&card->refcount);
ret = snd_card_disconnect(card);
if (ret) {
atomic_dec(&card->refcount);
return ret;
}
card->free_on_last_close = 1;
if (atomic_dec_and_test(&card->refcount))
put_device(&card->card_dev);
return 0;
}
EXPORT_SYMBOL(snd_card_free_when_closed);
int snd_card_free(struct snd_card *card)
{
int ret = snd_card_disconnect(card);
if (ret)
return ret;
/* wait, until all devices are ready for the free operation */
wait_event(card->shutdown_sleep, !atomic_read(&card->refcount));
put_device(&card->card_dev);
return 0;
}
EXPORT_SYMBOL(snd_card_free_when_closed);
int snd_card_free(struct snd_card *card)
{
struct completion released;
int ret;
init_completion(&released);
card->release_completion = &released;
ret = snd_card_free_when_closed(card);
if (ret)
return ret;
/* wait, until all devices are ready for the free operation */
wait_for_completion(&released);
return 0;
}
EXPORT_SYMBOL(snd_card_free);
/* retrieve the last word of shortname or longname */
@ -932,7 +909,7 @@ 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);
get_device(&card->card_dev);
spin_unlock(&card->files_lock);
return 0;
}
@ -975,7 +952,7 @@ int snd_card_file_remove(struct snd_card *card, struct file *file)
return -ENOENT;
}
kfree(found);
snd_card_unref(card);
put_device(&card->card_dev);
return 0;
}

View File

@ -118,7 +118,7 @@ void *snd_lookup_minor_data(unsigned int minor, int type)
if (mreg && mreg->type == type) {
private_data = mreg->private_data;
if (private_data && mreg->card_ptr)
atomic_inc(&mreg->card_ptr->refcount);
get_device(&mreg->card_ptr->card_dev);
} else
private_data = NULL;
mutex_unlock(&sound_mutex);

View File

@ -55,7 +55,7 @@ void *snd_lookup_oss_minor_data(unsigned int minor, int type)
if (mreg && mreg->type == type) {
private_data = mreg->private_data;
if (private_data && mreg->card_ptr)
atomic_inc(&mreg->card_ptr->refcount);
get_device(&mreg->card_ptr->card_dev);
} else
private_data = NULL;
mutex_unlock(&sound_oss_mutex);