Ejemplo n.º 1
0
/*
 * Handle retransmission and deferred ACK/abort generation.
 */
void rxrpc_process_call(struct work_struct *work)
{
	struct rxrpc_call *call =
		container_of(work, struct rxrpc_call, processor);
	ktime_t now;

	rxrpc_see_call(call);

	//printk("\n--------------------\n");
	_enter("{%d,%s,%lx}",
	       call->debug_id, rxrpc_call_states[call->state], call->events);

recheck_state:
	if (test_and_clear_bit(RXRPC_CALL_EV_ABORT, &call->events)) {
		rxrpc_send_abort_packet(call);
		goto recheck_state;
	}

	if (call->state == RXRPC_CALL_COMPLETE) {
		del_timer_sync(&call->timer);
		rxrpc_notify_socket(call);
		goto out_put;
	}

	now = ktime_get_real();
	if (ktime_before(call->expire_at, now)) {
		rxrpc_abort_call("EXP", call, 0, RX_CALL_TIMEOUT, ETIME);
		set_bit(RXRPC_CALL_EV_ABORT, &call->events);
		goto recheck_state;
	}

	if (test_and_clear_bit(RXRPC_CALL_EV_ACK, &call->events)) {
		if (call->ackr_reason) {
			rxrpc_send_ack_packet(call, false);
			goto recheck_state;
		}
	}

	if (test_and_clear_bit(RXRPC_CALL_EV_PING, &call->events)) {
		rxrpc_send_ack_packet(call, true);
		goto recheck_state;
	}

	if (test_and_clear_bit(RXRPC_CALL_EV_RESEND, &call->events)) {
		rxrpc_resend(call, now);
		goto recheck_state;
	}

	rxrpc_set_timer(call, rxrpc_timer_set_for_resend, now);

	/* other events may have been raised since we started checking */
	if (call->events && call->state < RXRPC_CALL_COMPLETE) {
		__rxrpc_queue_call(call);
		goto out;
	}

out_put:
	rxrpc_put_call(call, rxrpc_call_put);
out:
	_leave("");
}
Ejemplo n.º 2
0
/*
 * Allocate a new incoming call from the prealloc pool, along with a connection
 * and a peer as necessary.
 */
static struct rxrpc_call *rxrpc_alloc_incoming_call(struct rxrpc_sock *rx,
						    struct rxrpc_local *local,
						    struct rxrpc_connection *conn,
						    struct sk_buff *skb)
{
	struct rxrpc_backlog *b = rx->backlog;
	struct rxrpc_peer *peer, *xpeer;
	struct rxrpc_call *call;
	unsigned short call_head, conn_head, peer_head;
	unsigned short call_tail, conn_tail, peer_tail;
	unsigned short call_count, conn_count;

	/* #calls >= #conns >= #peers must hold true. */
	call_head = smp_load_acquire(&b->call_backlog_head);
	call_tail = b->call_backlog_tail;
	call_count = CIRC_CNT(call_head, call_tail, RXRPC_BACKLOG_MAX);
	conn_head = smp_load_acquire(&b->conn_backlog_head);
	conn_tail = b->conn_backlog_tail;
	conn_count = CIRC_CNT(conn_head, conn_tail, RXRPC_BACKLOG_MAX);
	ASSERTCMP(conn_count, >=, call_count);
	peer_head = smp_load_acquire(&b->peer_backlog_head);
	peer_tail = b->peer_backlog_tail;
	ASSERTCMP(CIRC_CNT(peer_head, peer_tail, RXRPC_BACKLOG_MAX), >=,
		  conn_count);

	if (call_count == 0)
		return NULL;

	if (!conn) {
		/* No connection.  We're going to need a peer to start off
		 * with.  If one doesn't yet exist, use a spare from the
		 * preallocation set.  We dump the address into the spare in
		 * anticipation - and to save on stack space.
		 */
		xpeer = b->peer_backlog[peer_tail];
		if (rxrpc_extract_addr_from_skb(&xpeer->srx, skb) < 0)
			return NULL;

		peer = rxrpc_lookup_incoming_peer(local, xpeer);
		if (peer == xpeer) {
			b->peer_backlog[peer_tail] = NULL;
			smp_store_release(&b->peer_backlog_tail,
					  (peer_tail + 1) &
					  (RXRPC_BACKLOG_MAX - 1));
		}

		/* Now allocate and set up the connection */
		conn = b->conn_backlog[conn_tail];
		b->conn_backlog[conn_tail] = NULL;
		smp_store_release(&b->conn_backlog_tail,
				  (conn_tail + 1) & (RXRPC_BACKLOG_MAX - 1));
		rxrpc_get_local(local);
		conn->params.local = local;
		conn->params.peer = peer;
		rxrpc_see_connection(conn);
		rxrpc_new_incoming_connection(rx, conn, skb);
	} else {
		rxrpc_get_connection(conn);
	}

	/* And now we can allocate and set up a new call */
	call = b->call_backlog[call_tail];
	b->call_backlog[call_tail] = NULL;
	smp_store_release(&b->call_backlog_tail,
			  (call_tail + 1) & (RXRPC_BACKLOG_MAX - 1));

	rxrpc_see_call(call);
	call->conn = conn;
	call->peer = rxrpc_get_peer(conn->params.peer);
	call->cong_cwnd = call->peer->cong_cwnd;
	return call;
}