static ssize_t smsdvb_stats_read(struct file *file, char __user *user_buf,
size_t nbytes, loff_t *ppos)
{
int rc = 0, len;
struct smsdvb_debugfs *debug_data = file->private_data;
kref_get(&debug_data->refcount);
if (file->f_flags & O_NONBLOCK) {
rc = smsdvb_stats_wait_read(debug_data);
if (!rc) {
rc = -EWOULDBLOCK;
goto ret;
}
} else {
rc = wait_event_interruptible(debug_data->stats_queue,
smsdvb_stats_wait_read(debug_data));
if (rc < 0)
goto ret;
}
if (debug_data->stats_was_read) {
rc = 0; /* EOF */
goto ret;
}
len = debug_data->stats_count - *ppos;
if (len >= 0)
rc = simple_read_from_buffer(user_buf, nbytes, ppos,
debug_data->stats_data, len);
else
rc = 0;
if (*ppos >= debug_data->stats_count) {
spin_lock(&debug_data->lock);
debug_data->stats_was_read = true;
spin_unlock(&debug_data->lock);
}
ret:
kref_put(&debug_data->refcount, smsdvb_debugfs_data_release);
return rc;
}
static __poll_t smsdvb_stats_poll(struct file *file, poll_table *wait)
{
struct smsdvb_debugfs *debug_data = file->private_data;
int rc;
kref_get(&debug_data->refcount);
poll_wait(file, &debug_data->stats_queue, wait);
rc = smsdvb_stats_wait_read(debug_data);
kref_put(&debug_data->refcount, smsdvb_debugfs_data_release);
return rc > 0 ? EPOLLIN | EPOLLRDNORM : 0;
}
