Merge remote-tracking branch 'lsk/v4.4/topic/ro-vdso' into linux-linaro-lsk-v4.4

[firefly-linux-kernel-4.4.55.git] / sound / core / timer.c

diff --git a/sound/core/timer.c b/sound/core/timer.c
index 31f40f03e5b79c8aac7cb96a793ffdd7bff94e15..0a049c4578f1db0807f2bd94ed111181e18efd11 100644 (file)
--- a/sound/core/timer.c
+++ b/sound/core/timer.c
@@ -65,6 +65,7 @@ struct snd_timer_user {
        int qtail;
        int qused;
        int queue_size;
+       bool disconnected;
        struct snd_timer_read *queue;
        struct snd_timer_tread *tqueue;
        spinlock_t qlock;
@@ -73,7 +74,7 @@ struct snd_timer_user {
        struct timespec tstamp;         /* trigger tstamp */
        wait_queue_head_t qchange_sleep;
        struct fasync_struct *fasync;
-       struct mutex tread_sem;
+       struct mutex ioctl_lock;
 };
 
 /* list of timers */
@@ -215,11 +216,13 @@ static void snd_timer_check_master(struct snd_timer_instance *master)
                    slave->slave_id == master->slave_id) {
                        list_move_tail(&slave->open_list, &master->slave_list_head);
                        spin_lock_irq(&slave_active_lock);
+                       spin_lock(&master->timer->lock);
                        slave->master = master;
                        slave->timer = master->timer;
                        if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
                                list_add_tail(&slave->active_list,
                                              &master->slave_active_head);
+                       spin_unlock(&master->timer->lock);
                        spin_unlock_irq(&slave_active_lock);
                }
        }
@@ -288,6 +291,9 @@ int snd_timer_open(struct snd_timer_instance **ti,
                mutex_unlock(&register_mutex);
                return -ENOMEM;
        }
+       /* take a card refcount for safe disconnection */
+       if (timer->card)
+               get_device(&timer->card->card_dev);
        timeri->slave_class = tid->dev_sclass;
        timeri->slave_id = slave_id;
        if (list_empty(&timer->open_list_head) && timer->hw.open)
@@ -346,15 +352,21 @@ int snd_timer_close(struct snd_timer_instance *timeri)
                    timer->hw.close)
                        timer->hw.close(timer);
                /* remove slave links */
+               spin_lock_irq(&slave_active_lock);
+               spin_lock(&timer->lock);
                list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head,
                                         open_list) {
-                       spin_lock_irq(&slave_active_lock);
-                       _snd_timer_stop(slave, 1, SNDRV_TIMER_EVENT_RESOLUTION);
                        list_move_tail(&slave->open_list, &snd_timer_slave_list);
                        slave->master = NULL;
                        slave->timer = NULL;
-                       spin_unlock_irq(&slave_active_lock);
+                       list_del_init(&slave->ack_list);
+                       list_del_init(&slave->active_list);
                }
+               spin_unlock(&timer->lock);
+               spin_unlock_irq(&slave_active_lock);
+               /* release a card refcount for safe disconnection */
+               if (timer->card)
+                       put_device(&timer->card->card_dev);
                mutex_unlock(&register_mutex);
        }
  out:
@@ -441,9 +453,12 @@ static int snd_timer_start_slave(struct snd_timer_instance *timeri)
 
        spin_lock_irqsave(&slave_active_lock, flags);
        timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
-       if (timeri->master)
+       if (timeri->master && timeri->timer) {
+               spin_lock(&timeri->timer->lock);
                list_add_tail(&timeri->active_list,
                              &timeri->master->slave_active_head);
+               spin_unlock(&timeri->timer->lock);
+       }
        spin_unlock_irqrestore(&slave_active_lock, flags);
        return 1; /* delayed start */
 }
@@ -467,6 +482,8 @@ int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
        timer = timeri->timer;
        if (timer == NULL)
                return -EINVAL;
+       if (timer->card && timer->card->shutdown)
+               return -ENODEV;
        spin_lock_irqsave(&timer->lock, flags);
        timeri->ticks = timeri->cticks = ticks;
        timeri->pticks = 0;
@@ -489,6 +506,8 @@ static int _snd_timer_stop(struct snd_timer_instance * timeri,
                if (!keep_flag) {
                        spin_lock_irqsave(&slave_active_lock, flags);
                        timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
+                       list_del_init(&timeri->ack_list);
+                       list_del_init(&timeri->active_list);
                        spin_unlock_irqrestore(&slave_active_lock, flags);
                }
                goto __end;
@@ -499,6 +518,10 @@ static int _snd_timer_stop(struct snd_timer_instance * timeri,
        spin_lock_irqsave(&timer->lock, flags);
        list_del_init(&timeri->ack_list);
        list_del_init(&timeri->active_list);
+       if (timer->card && timer->card->shutdown) {
+               spin_unlock_irqrestore(&timer->lock, flags);
+               return 0;
+       }
        if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
            !(--timer->running)) {
                timer->hw.stop(timer);
@@ -561,6 +584,8 @@ int snd_timer_continue(struct snd_timer_instance *timeri)
        timer = timeri->timer;
        if (! timer)
                return -EINVAL;
+       if (timer->card && timer->card->shutdown)
+               return -ENODEV;
        spin_lock_irqsave(&timer->lock, flags);
        if (!timeri->cticks)
                timeri->cticks = 1;
@@ -624,6 +649,9 @@ static void snd_timer_tasklet(unsigned long arg)
        unsigned long resolution, ticks;
        unsigned long flags;
 
+       if (timer->card && timer->card->shutdown)
+               return;
+
        spin_lock_irqsave(&timer->lock, flags);
        /* now process all callbacks */
        while (!list_empty(&timer->sack_list_head)) {
@@ -664,6 +692,9 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
        if (timer == NULL)
                return;
 
+       if (timer->card && timer->card->shutdown)
+               return;
+
        spin_lock_irqsave(&timer->lock, flags);
 
        /* remember the current resolution */
@@ -694,7 +725,7 @@ void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
                } else {
                        ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
                        if (--timer->running)
-                               list_del(&ti->active_list);
+                               list_del_init(&ti->active_list);
                }
                if ((timer->hw.flags & SNDRV_TIMER_HW_TASKLET) ||
                    (ti->flags & SNDRV_TIMER_IFLG_FAST))
@@ -874,11 +905,28 @@ static int snd_timer_dev_register(struct snd_device *dev)
        return 0;
 }
 
+/* just for reference in snd_timer_dev_disconnect() below */
+static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
+                                    int event, struct timespec *tstamp,
+                                    unsigned long resolution);
+
 static int snd_timer_dev_disconnect(struct snd_device *device)
 {
        struct snd_timer *timer = device->device_data;
+       struct snd_timer_instance *ti;
+
        mutex_lock(&register_mutex);
        list_del_init(&timer->device_list);
+       /* wake up pending sleepers */
+       list_for_each_entry(ti, &timer->open_list_head, open_list) {
+               /* FIXME: better to have a ti.disconnect() op */
+               if (ti->ccallback == snd_timer_user_ccallback) {
+                       struct snd_timer_user *tu = ti->callback_data;
+
+                       tu->disconnected = true;
+                       wake_up(&tu->qchange_sleep);
+               }
+       }
        mutex_unlock(&register_mutex);
        return 0;
 }
@@ -889,6 +937,8 @@ void snd_timer_notify(struct snd_timer *timer, int event, struct timespec *tstam
        unsigned long resolution = 0;
        struct snd_timer_instance *ti, *ts;
 
+       if (timer->card && timer->card->shutdown)
+               return;
        if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
                return;
        if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
@@ -1047,6 +1097,8 @@ static void snd_timer_proc_read(struct snd_info_entry *entry,
 
        mutex_lock(&register_mutex);
        list_for_each_entry(timer, &snd_timer_list, device_list) {
+               if (timer->card && timer->card->shutdown)
+                       continue;
                switch (timer->tmr_class) {
                case SNDRV_TIMER_CLASS_GLOBAL:
                        snd_iprintf(buffer, "G%i: ", timer->tmr_device);
@@ -1253,7 +1305,7 @@ 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);
-       mutex_init(&tu->tread_sem);
+       mutex_init(&tu->ioctl_lock);
        tu->ticks = 1;
        tu->queue_size = 128;
        tu->queue = kmalloc(tu->queue_size * sizeof(struct snd_timer_read),
@@ -1273,8 +1325,10 @@ static int snd_timer_user_release(struct inode *inode, struct file *file)
        if (file->private_data) {
                tu = file->private_data;
                file->private_data = NULL;
+               mutex_lock(&tu->ioctl_lock);
                if (tu->timeri)
                        snd_timer_close(tu->timeri);
+               mutex_unlock(&tu->ioctl_lock);
                kfree(tu->queue);
                kfree(tu->tqueue);
                kfree(tu);
@@ -1512,7 +1566,6 @@ static int snd_timer_user_tselect(struct file *file,
        int err = 0;
 
        tu = file->private_data;
-       mutex_lock(&tu->tread_sem);
        if (tu->timeri) {
                snd_timer_close(tu->timeri);
                tu->timeri = NULL;
@@ -1556,7 +1609,6 @@ static int snd_timer_user_tselect(struct file *file,
        }
 
       __err:
-       mutex_unlock(&tu->tread_sem);
        return err;
 }
 
@@ -1769,7 +1821,7 @@ enum {
        SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
 };
 
-static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
+static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
                                 unsigned long arg)
 {
        struct snd_timer_user *tu;
@@ -1786,17 +1838,11 @@ static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
        {
                int xarg;
 
-               mutex_lock(&tu->tread_sem);
-               if (tu->timeri) {       /* too late */
-                       mutex_unlock(&tu->tread_sem);
+               if (tu->timeri) /* too late */
                        return -EBUSY;
-               }
-               if (get_user(xarg, p)) {
-                       mutex_unlock(&tu->tread_sem);
+               if (get_user(xarg, p))
                        return -EFAULT;
-               }
                tu->tread = xarg ? 1 : 0;
-               mutex_unlock(&tu->tread_sem);
                return 0;
        }
        case SNDRV_TIMER_IOCTL_GINFO:
@@ -1829,6 +1875,18 @@ static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
        return -ENOTTY;
 }
 
+static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
+                                unsigned long arg)
+{
+       struct snd_timer_user *tu = file->private_data;
+       long ret;
+
+       mutex_lock(&tu->ioctl_lock);
+       ret = __snd_timer_user_ioctl(file, cmd, arg);
+       mutex_unlock(&tu->ioctl_lock);
+       return ret;
+}
+
 static int snd_timer_user_fasync(int fd, struct file * file, int on)
 {
        struct snd_timer_user *tu;
@@ -1866,6 +1924,10 @@ static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
 
                        remove_wait_queue(&tu->qchange_sleep, &wait);
 
+                       if (tu->disconnected) {
+                               err = -ENODEV;
+                               break;
+                       }
                        if (signal_pending(current)) {
                                err = -ERESTARTSYS;
                                break;
@@ -1915,6 +1977,8 @@ static unsigned int snd_timer_user_poll(struct file *file, poll_table * wait)
        mask = 0;
        if (tu->qused)
                mask |= POLLIN | POLLRDNORM;
+       if (tu->disconnected)
+               mask |= POLLERR;
 
        return mask;
 }