diff options
Diffstat (limited to 'sound')
| -rw-r--r-- | sound/core/hrtimer.c | 1 | ||||
| -rw-r--r-- | sound/core/timer.c | 67 |
2 files changed, 55 insertions, 13 deletions
diff --git a/sound/core/hrtimer.c b/sound/core/hrtimer.c index 1ac0c423903e..6e47b823bcaa 100644 --- a/sound/core/hrtimer.c +++ b/sound/core/hrtimer.c @@ -159,6 +159,7 @@ static int __init snd_hrtimer_init(void) timer->hw = hrtimer_hw; timer->hw.resolution = resolution; timer->hw.ticks = NANO_SEC / resolution; + timer->max_instances = 100; /* lower the limit */ err = snd_timer_global_register(timer); if (err < 0) { diff --git a/sound/core/timer.c b/sound/core/timer.c index a9b9a277e00c..c8e4d0da13b4 100644 --- a/sound/core/timer.c +++ b/sound/core/timer.c @@ -180,7 +180,7 @@ static void snd_timer_request(struct snd_timer_id *tid) * * call this with register_mutex down. */ -static void snd_timer_check_slave(struct snd_timer_instance *slave) +static int snd_timer_check_slave(struct snd_timer_instance *slave) { struct snd_timer *timer; struct snd_timer_instance *master; @@ -190,16 +190,21 @@ static void snd_timer_check_slave(struct snd_timer_instance *slave) list_for_each_entry(master, &timer->open_list_head, open_list) { if (slave->slave_class == master->slave_class && slave->slave_id == master->slave_id) { + if (master->timer->num_instances >= + master->timer->max_instances) + return -EBUSY; list_move_tail(&slave->open_list, &master->slave_list_head); + master->timer->num_instances++; spin_lock_irq(&slave_active_lock); slave->master = master; slave->timer = master->timer; spin_unlock_irq(&slave_active_lock); - return; + return 0; } } } + return 0; } /* @@ -208,7 +213,7 @@ static void snd_timer_check_slave(struct snd_timer_instance *slave) * * call this with register_mutex down. */ -static void snd_timer_check_master(struct snd_timer_instance *master) +static int snd_timer_check_master(struct snd_timer_instance *master) { struct snd_timer_instance *slave, *tmp; @@ -216,7 +221,11 @@ static void snd_timer_check_master(struct snd_timer_instance *master) list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) { if (slave->slave_class == master->slave_class && slave->slave_id == master->slave_id) { + if (master->timer->num_instances >= + master->timer->max_instances) + return -EBUSY; list_move_tail(&slave->open_list, &master->slave_list_head); + master->timer->num_instances++; spin_lock_irq(&slave_active_lock); spin_lock(&master->timer->lock); slave->master = master; @@ -228,8 +237,11 @@ static void snd_timer_check_master(struct snd_timer_instance *master) spin_unlock_irq(&slave_active_lock); } } + return 0; } +static int snd_timer_close_locked(struct snd_timer_instance *timeri); + /* * open a timer instance * when opening a master, the slave id must be here given. @@ -240,6 +252,7 @@ int snd_timer_open(struct snd_timer_instance **ti, { struct snd_timer *timer; struct snd_timer_instance *timeri = NULL; + int err; if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) { /* open a slave instance */ @@ -259,10 +272,14 @@ int snd_timer_open(struct snd_timer_instance **ti, timeri->slave_id = tid->device; timeri->flags |= SNDRV_TIMER_IFLG_SLAVE; list_add_tail(&timeri->open_list, &snd_timer_slave_list); - snd_timer_check_slave(timeri); + err = snd_timer_check_slave(timeri); + if (err < 0) { + snd_timer_close_locked(timeri); + timeri = NULL; + } mutex_unlock(®ister_mutex); *ti = timeri; - return 0; + return err; } /* open a master instance */ @@ -288,6 +305,10 @@ int snd_timer_open(struct snd_timer_instance **ti, return -EBUSY; } } + if (timer->num_instances >= timer->max_instances) { + mutex_unlock(®ister_mutex); + return -EBUSY; + } timeri = snd_timer_instance_new(owner, timer); if (!timeri) { mutex_unlock(®ister_mutex); @@ -314,25 +335,27 @@ int snd_timer_open(struct snd_timer_instance **ti, } list_add_tail(&timeri->open_list, &timer->open_list_head); - snd_timer_check_master(timeri); + timer->num_instances++; + err = snd_timer_check_master(timeri); + if (err < 0) { + snd_timer_close_locked(timeri); + timeri = NULL; + } mutex_unlock(®ister_mutex); *ti = timeri; - return 0; + return err; } EXPORT_SYMBOL(snd_timer_open); /* * close a timer instance + * call this with register_mutex down. */ -int snd_timer_close(struct snd_timer_instance *timeri) +static int snd_timer_close_locked(struct snd_timer_instance *timeri) { struct snd_timer *timer = NULL; struct snd_timer_instance *slave, *tmp; - if (snd_BUG_ON(!timeri)) - return -ENXIO; - - mutex_lock(®ister_mutex); list_del(&timeri->open_list); /* force to stop the timer */ @@ -340,6 +363,7 @@ int snd_timer_close(struct snd_timer_instance *timeri) timer = timeri->timer; if (timer) { + timer->num_instances--; /* wait, until the active callback is finished */ spin_lock_irq(&timer->lock); while (timeri->flags & SNDRV_TIMER_IFLG_CALLBACK) { @@ -355,6 +379,7 @@ int snd_timer_close(struct snd_timer_instance *timeri) list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head, open_list) { list_move_tail(&slave->open_list, &snd_timer_slave_list); + timer->num_instances--; slave->master = NULL; slave->timer = NULL; list_del_init(&slave->ack_list); @@ -382,9 +407,24 @@ int snd_timer_close(struct snd_timer_instance *timeri) module_put(timer->module); } - mutex_unlock(®ister_mutex); return 0; } + +/* + * close a timer instance + */ +int snd_timer_close(struct snd_timer_instance *timeri) +{ + int err; + + if (snd_BUG_ON(!timeri)) + return -ENXIO; + + mutex_lock(®ister_mutex); + err = snd_timer_close_locked(timeri); + mutex_unlock(®ister_mutex); + return err; +} EXPORT_SYMBOL(snd_timer_close); unsigned long snd_timer_resolution(struct snd_timer_instance *timeri) @@ -855,6 +895,7 @@ int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid, spin_lock_init(&timer->lock); tasklet_init(&timer->task_queue, snd_timer_tasklet, (unsigned long)timer); + timer->max_instances = 1000; /* default limit per timer */ if (card != NULL) { timer->module = card->module; err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops); |
