fw-cdev.c

	enum dma_data_direction direction;
	unsigned long size;
	int page_count, ret;

	if (fw_device_is_shutdown(client->device))
		return -ENODEV;

	/* FIXME: We could support multiple buffers, but we don't. */
	if (client->buffer.pages != NULL)
		return -EBUSY;

	if (!(vma->vm_flags & VM_SHARED))
		return -EINVAL;

	if (vma->vm_start & ~PAGE_MASK)
		return -EINVAL;

	client->vm_start = vma->vm_start;
	size = vma->vm_end - vma->vm_start;
	page_count = size >> PAGE_SHIFT;
	if (size & ~PAGE_MASK)
		return -EINVAL;

	if (vma->vm_flags & VM_WRITE)
		direction = DMA_TO_DEVICE;
	else
		direction = DMA_FROM_DEVICE;

	ret = fw_iso_buffer_init(&client->buffer, client->device->card,
				 page_count, direction);
	if (ret < 0)
		return ret;

	ret = fw_iso_buffer_map(&client->buffer, vma);
	if (ret < 0)
		fw_iso_buffer_destroy(&client->buffer, client->device->card);

	return ret;
}

static int shutdown_resource(int id, void *p, void *data)
{
	struct client_resource *r = p;
	struct client *client = data;

	r->release(client, r);

	return 0;
}

static int fw_device_op_release(struct inode *inode, struct file *file)
{
	struct client *client = file->private_data;
	struct event *e, *next_e;
	unsigned long flags;

	mutex_lock(&client->device->client_list_mutex);
	list_del(&client->link);
	mutex_unlock(&client->device->client_list_mutex);

	if (client->buffer.pages)
		fw_iso_buffer_destroy(&client->buffer, client->device->card);

	if (client->iso_context)
		fw_iso_context_destroy(client->iso_context);

	/* Freeze client->resource_idr and client->event_list */
	spin_lock_irqsave(&client->lock, flags);
	client->in_shutdown = true;
	spin_unlock_irqrestore(&client->lock, flags);

	idr_for_each(&client->resource_idr, shutdown_resource, client);
	idr_remove_all(&client->resource_idr);
	idr_destroy(&client->resource_idr);

	list_for_each_entry_safe(e, next_e, &client->event_list, link)
		kfree(e);

	/*
	 * FIXME: client should be reference-counted.  It's extremely unlikely
	 * but there may still be transactions being completed at this point.
	 */
	fw_device_put(client->device);
	kfree(client);

	return 0;
}

static unsigned int fw_device_op_poll(struct file *file, poll_table * pt)
{
	struct client *client = file->private_data;
	unsigned int mask = 0;

	poll_wait(file, &client->wait, pt);

	if (fw_device_is_shutdown(client->device))
		mask |= POLLHUP | POLLERR;
	if (!list_empty(&client->event_list))
		mask |= POLLIN | POLLRDNORM;

	return mask;
}

const struct file_operations fw_device_ops = {
	.owner		= THIS_MODULE,
	.open		= fw_device_op_open,
	.read		= fw_device_op_read,
	.unlocked_ioctl	= fw_device_op_ioctl,
	.poll		= fw_device_op_poll,
	.release	= fw_device_op_release,
	.mmap		= fw_device_op_mmap,

#ifdef CONFIG_COMPAT
	.compat_ioctl	= fw_device_op_compat_ioctl,
#endif
};