firewire: Preserve response data alignment bug when it is harmless

	struct response *response = data;

	struct client *client = response->client;

	unsigned long flags;

	struct fw_cdev_event_response *r = &response->response;

	if (length < response->response.length)

		response->response.length = length;

	if (length < r->length)

		r->length = length;

	if (rcode == RCODE_COMPLETE)

		memcpy(response->response.data, payload,

		       response->response.length);

		memcpy(r->data, payload, r->length);

	spin_lock_irqsave(&client->lock, flags);

	list_del(&response->resource.link);

	spin_unlock_irqrestore(&client->lock, flags);

	response->response.type   = FW_CDEV_EVENT_RESPONSE;

	response->response.rcode  = rcode;

	queue_event(client, &response->event, &response->response,

		    sizeof(response->response) + response->response.length,

	r->type   = FW_CDEV_EVENT_RESPONSE;

	r->rcode  = rcode;

	/*

	 * In the case that sizeof(*r) doesn't align with the position of the

	 * data, and the read is short, preserve an extra copy of the data

	 * to stay compatible with a pre-2.6.27 bug.  Since the bug is harmless

	 * for short reads and some apps depended on it, this is both safe

	 * and prudent for compatibility.

	 */

	if (r->length <= sizeof(*r) - offsetof(typeof(*r), data))

		queue_event(client, &response->event, r, sizeof(*r),

			    r->data, r->length);

	else

		queue_event(client, &response->event, r, sizeof(*r) + r->length,

			    NULL, 0);

}