diff options
Diffstat (limited to 'sound/core')
| -rw-r--r-- | sound/core/timer.c | 57 |
1 files changed, 37 insertions, 20 deletions
diff --git a/sound/core/timer.c b/sound/core/timer.c index fa762ca439b..be6d37af76d 100644 --- a/sound/core/timer.c +++ b/sound/core/timer.c @@ -69,6 +69,7 @@ typedef struct { struct timespec tstamp; /* trigger tstamp */ wait_queue_head_t qchange_sleep; struct fasync_struct *fasync; + struct semaphore tread_sem; } snd_timer_user_t; /* list of timers */ @@ -1208,6 +1209,7 @@ static int snd_timer_user_open(struct inode *inode, struct file *file) return -ENOMEM; spin_lock_init(&tu->qlock); init_waitqueue_head(&tu->qchange_sleep); + init_MUTEX(&tu->tread_sem); tu->ticks = 1; tu->queue_size = 128; tu->queue = (snd_timer_read_t *)kmalloc(tu->queue_size * sizeof(snd_timer_read_t), GFP_KERNEL); @@ -1454,18 +1456,23 @@ static int snd_timer_user_tselect(struct file *file, snd_timer_select_t __user * snd_timer_user_t *tu; snd_timer_select_t tselect; char str[32]; - int err; + int err = 0; tu = file->private_data; - if (tu->timeri) + down(&tu->tread_sem); + if (tu->timeri) { snd_timer_close(tu->timeri); - if (copy_from_user(&tselect, _tselect, sizeof(tselect))) - return -EFAULT; + tu->timeri = NULL; + } + if (copy_from_user(&tselect, _tselect, sizeof(tselect))) { + err = -EFAULT; + goto __err; + } sprintf(str, "application %i", current->pid); if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE) tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION; if ((err = snd_timer_open(&tu->timeri, str, &tselect.id, current->pid)) < 0) - return err; + goto __err; if (tu->queue) { kfree(tu->queue); @@ -1477,23 +1484,27 @@ static int snd_timer_user_tselect(struct file *file, snd_timer_select_t __user * } if (tu->tread) { tu->tqueue = (snd_timer_tread_t *)kmalloc(tu->queue_size * sizeof(snd_timer_tread_t), GFP_KERNEL); - if (tu->tqueue == NULL) { - snd_timer_close(tu->timeri); - return -ENOMEM; - } + if (tu->tqueue == NULL) + err = -ENOMEM; } else { tu->queue = (snd_timer_read_t *)kmalloc(tu->queue_size * sizeof(snd_timer_read_t), GFP_KERNEL); - if (tu->queue == NULL) { - snd_timer_close(tu->timeri); - return -ENOMEM; - } + if (tu->queue == NULL) + err = -ENOMEM; } - tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST; - tu->timeri->callback = tu->tread ? snd_timer_user_tinterrupt : snd_timer_user_interrupt; - tu->timeri->ccallback = snd_timer_user_ccallback; - tu->timeri->callback_data = (void *)tu; - return 0; + if (err < 0) { + snd_timer_close(tu->timeri); + tu->timeri = NULL; + } else { + tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST; + tu->timeri->callback = tu->tread ? snd_timer_user_tinterrupt : snd_timer_user_interrupt; + tu->timeri->ccallback = snd_timer_user_ccallback; + tu->timeri->callback_data = (void *)tu; + } + + __err: + up(&tu->tread_sem); + return err; } static int snd_timer_user_info(struct file *file, snd_timer_info_t __user *_info) @@ -1685,11 +1696,17 @@ static long snd_timer_user_ioctl(struct file *file, unsigned int cmd, unsigned l { int xarg; - if (tu->timeri) /* too late */ + down(&tu->tread_sem); + if (tu->timeri) { /* too late */ + up(&tu->tread_sem); return -EBUSY; - if (get_user(xarg, p)) + } + if (get_user(xarg, p)) { + up(&tu->tread_sem); return -EFAULT; + } tu->tread = xarg ? 1 : 0; + up(&tu->tread_sem); return 0; } case SNDRV_TIMER_IOCTL_GINFO: |