static void x25_timer_expiry(unsigned long param)
{
	struct sock *sk = (struct sock *)param;

	bh_lock_sock(sk);
	if (sock_owned_by_user(sk)) { /* can currently only occur in state 3 */
		if (x25_sk(sk)->state == X25_STATE_3)
			x25_start_t2timer(sk);
	} else
		x25_do_timer_expiry(sk);
	bh_unlock_sock(sk);
}
예제 #2
0
/*
 * State machine for state 3, Connected State.
 * The handling of the timer(s) is in file x25_timer.c
 * Handling of state 0 and connection release is in af_x25.c.
 */
static int x25_state3_machine(struct sock *sk, struct sk_buff *skb, int frametype, int ns, int nr, int q, int d, int m)
{
	int queued = 0;
	int modulus;
	struct x25_sock *x25 = x25_sk(sk);

	modulus = (x25->neighbour->extended) ? X25_EMODULUS : X25_SMODULUS;

	switch (frametype) {

		case X25_RESET_REQUEST:
			x25_write_internal(sk, X25_RESET_CONFIRMATION);
			x25_stop_timer(sk);
			x25->condition = 0x00;
			x25->vs        = 0;
			x25->vr        = 0;
			x25->va        = 0;
			x25->vl        = 0;
			x25_requeue_frames(sk);
			break;

		case X25_CLEAR_REQUEST:
			x25_write_internal(sk, X25_CLEAR_CONFIRMATION);
			x25_disconnect(sk, 0, skb->data[3], skb->data[4]);
			break;

		case X25_RR:
		case X25_RNR:
			if (!x25_validate_nr(sk, nr)) {
				x25_clear_queues(sk);
				x25_write_internal(sk, X25_RESET_REQUEST);
				x25_start_t22timer(sk);
				x25->condition = 0x00;
				x25->vs        = 0;
				x25->vr        = 0;
				x25->va        = 0;
				x25->vl        = 0;
				x25->state     = X25_STATE_4;
			} else {
				x25_frames_acked(sk, nr);
				if (frametype == X25_RNR) {
					x25->condition |= X25_COND_PEER_RX_BUSY;
				} else {
					x25->condition &= ~X25_COND_PEER_RX_BUSY;
				}
			}
			break;

		case X25_DATA:	/* XXX */
			x25->condition &= ~X25_COND_PEER_RX_BUSY;
			if ((ns != x25->vr) || !x25_validate_nr(sk, nr)) {
				x25_clear_queues(sk);
				x25_write_internal(sk, X25_RESET_REQUEST);
				x25_start_t22timer(sk);
				x25->condition = 0x00;
				x25->vs        = 0;
				x25->vr        = 0;
				x25->va        = 0;
				x25->vl        = 0;
				x25->state     = X25_STATE_4;
				break;
			}
			x25_frames_acked(sk, nr);
			if (ns == x25->vr) {
				if (x25_queue_rx_frame(sk, skb, m) == 0) {
					x25->vr = (x25->vr + 1) % modulus;
					queued = 1;
				} else {
					/* Should never happen */
					x25_clear_queues(sk);
					x25_write_internal(sk, X25_RESET_REQUEST);
					x25_start_t22timer(sk);
					x25->condition = 0x00;
					x25->vs        = 0;
					x25->vr        = 0;
					x25->va        = 0;
					x25->vl        = 0;
					x25->state     = X25_STATE_4;
					break;
				}
				if (atomic_read(&sk->sk_rmem_alloc) >
				    (sk->sk_rcvbuf / 2))
					x25->condition |= X25_COND_OWN_RX_BUSY;
			}
			/*
			 *	If the window is full Ack it immediately, else
			 *	start the holdback timer.
			 */
			if (((x25->vl + x25->facilities.winsize_in) % modulus) == x25->vr) {
				x25->condition &= ~X25_COND_ACK_PENDING;
				x25_stop_timer(sk);
				x25_enquiry_response(sk);
			} else {
				x25->condition |= X25_COND_ACK_PENDING;
				x25_start_t2timer(sk);
			}
			break;

		case X25_INTERRUPT_CONFIRMATION:
			x25->intflag = 0;
			break;

		case X25_INTERRUPT:
			if (sock_flag(sk, SOCK_URGINLINE))
				queued = !sock_queue_rcv_skb(sk, skb);
			else {
				skb_set_owner_r(skb, sk);
				skb_queue_tail(&x25->interrupt_in_queue, skb);
				queued = 1;
			}
			sk_send_sigurg(sk);
			x25_write_internal(sk, X25_INTERRUPT_CONFIRMATION);
			break;

		default:
			printk(KERN_WARNING "x25: unknown %02X in state 3\n", frametype);
			break;
	}

	return queued;
}