-static void link_retrieve_defq(struct tipc_link *link,
- struct sk_buff_head *list)
-{
- u16 seq_no;
-
- if (skb_queue_empty(&link->deferdq))
- return;
-
- seq_no = buf_seqno(skb_peek(&link->deferdq));
- if (seq_no == link->rcv_nxt)
- skb_queue_splice_tail_init(&link->deferdq, list);
-}
-
-/**
- * tipc_rcv - process TIPC packets/messages arriving from off-node
- * @net: the applicable net namespace
- * @skb: TIPC packet
- * @b_ptr: pointer to bearer message arrived on
- *
- * Invoked with no locks held. Bearer pointer must point to a valid bearer
- * structure (i.e. cannot be NULL), but bearer can be inactive.
- */
-void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b_ptr)
-{
- struct tipc_net *tn = net_generic(net, tipc_net_id);
- struct sk_buff_head head;
- struct tipc_node *n_ptr;
- struct tipc_link *l_ptr;
- struct sk_buff *skb1, *tmp;
- struct tipc_msg *msg;
- u16 seq_no;
- u16 ackd;
- u32 released;
-
- skb2list(skb, &head);
-
- while ((skb = __skb_dequeue(&head))) {
- /* Ensure message is well-formed */
- if (unlikely(!tipc_msg_validate(skb)))
- goto discard;
-
- /* Handle arrival of a non-unicast link message */
- msg = buf_msg(skb);
- if (unlikely(msg_non_seq(msg))) {
- if (msg_user(msg) == LINK_CONFIG)
- tipc_disc_rcv(net, skb, b_ptr);
- else
- tipc_bclink_rcv(net, skb);
- continue;
- }
-
- /* Discard unicast link messages destined for another node */
- if (unlikely(!msg_short(msg) &&
- (msg_destnode(msg) != tn->own_addr)))
- goto discard;
-
- /* Locate neighboring node that sent message */
- n_ptr = tipc_node_find(net, msg_prevnode(msg));
- if (unlikely(!n_ptr))
- goto discard;
-
- tipc_node_lock(n_ptr);
- /* Locate unicast link endpoint that should handle message */
- l_ptr = n_ptr->links[b_ptr->identity].link;
- if (unlikely(!l_ptr))
- goto unlock;
-
- /* Is reception of this pkt permitted at the moment ? */
- if (!tipc_node_filter_skb(n_ptr, msg))
- goto unlock;
-
- /* Validate message sequence number info */
- seq_no = msg_seqno(msg);
- ackd = msg_ack(msg);
-
- /* Release acked messages */
- if (unlikely(n_ptr->bclink.acked != msg_bcast_ack(msg)))
- tipc_bclink_acknowledge(n_ptr, msg_bcast_ack(msg));
-
- released = 0;
- skb_queue_walk_safe(&l_ptr->transmq, skb1, tmp) {
- if (more(buf_seqno(skb1), ackd))
- break;
- __skb_unlink(skb1, &l_ptr->transmq);
- kfree_skb(skb1);
- released = 1;
- }
-
- /* Try sending any messages link endpoint has pending */
- if (unlikely(skb_queue_len(&l_ptr->backlogq)))
- tipc_link_push_packets(l_ptr);
-
- if (released && !skb_queue_empty(&l_ptr->wakeupq))
- link_prepare_wakeup(l_ptr);
-
- /* Process the incoming packet */
- if (unlikely(!link_working(l_ptr))) {
- if (msg_user(msg) == LINK_PROTOCOL) {
- tipc_link_proto_rcv(l_ptr, skb);
- link_retrieve_defq(l_ptr, &head);
- skb = NULL;
- goto unlock;
- }
-
- /* Traffic message. Conditionally activate link */
- link_state_event(l_ptr, TRAFFIC_EVT);
-
- if (link_working(l_ptr)) {
- /* Re-insert buffer in front of queue */
- __skb_queue_head(&head, skb);
- skb = NULL;
- goto unlock;
- }
- goto unlock;
- }
-
- /* Link is now in state TIPC_LINK_WORKING */
- if (unlikely(seq_no != l_ptr->rcv_nxt)) {
- link_handle_out_of_seq_msg(l_ptr, skb);
- link_retrieve_defq(l_ptr, &head);
- skb = NULL;
- goto unlock;
- }
- l_ptr->silent_intv_cnt = 0;
-
- /* Synchronize with parallel link if applicable */
- if (unlikely((l_ptr->exec_mode == TIPC_LINK_TUNNEL) &&
- !msg_dup(msg))) {
- if (!link_synch(l_ptr))
- goto unlock;
- }
- l_ptr->rcv_nxt++;
- if (unlikely(!skb_queue_empty(&l_ptr->deferdq)))
- link_retrieve_defq(l_ptr, &head);
- if (unlikely(++l_ptr->rcv_unacked >= TIPC_MIN_LINK_WIN)) {
- l_ptr->stats.sent_acks++;
- tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0);
- }
- tipc_link_input(l_ptr, skb);
- skb = NULL;
-unlock:
- tipc_node_unlock(n_ptr);
- tipc_node_put(n_ptr);
-discard:
- if (unlikely(skb))
- kfree_skb(skb);
- }
-}
-