}
}
+/**
+ * tipc_link_failover_prepare() - prepare tnl for link failover
+ *
+ * This is a special version of the precursor - tipc_link_tnl_prepare(),
+ * see the tipc_node_link_failover() for details
+ *
+ * @l: failover link
+ * @tnl: tunnel link
+ * @xmitq: queue for messages to be xmited
+ */
+void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
+ struct sk_buff_head *xmitq)
+{
+ struct sk_buff_head *fdefq = &tnl->failover_deferdq;
+
+ tipc_link_create_dummy_tnl_msg(tnl, xmitq);
+
+ /* This failover link enpoint was never established before,
+ * so it has not received anything from peer.
+ * Otherwise, it must be a normal failover situation or the
+ * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
+ * would have to start over from scratch instead.
+ */
+ WARN_ON(l && tipc_link_is_up(l));
+ tnl->drop_point = 1;
+ tnl->failover_reasm_skb = NULL;
+
+ /* Initiate the link's failover deferdq */
+ if (unlikely(!skb_queue_empty(fdefq))) {
+ pr_warn("Link failover deferdq not empty: %d!\n",
+ skb_queue_len(fdefq));
+ __skb_queue_purge(fdefq);
+ }
+}
+
/* tipc_link_validate_msg(): validate message against current link state
* Returns true if message should be accepted, otherwise false
*/
int mtyp, struct sk_buff_head *xmitq);
void tipc_link_create_dummy_tnl_msg(struct tipc_link *tnl,
struct sk_buff_head *xmitq);
+void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
+ struct sk_buff_head *xmitq);
void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq);
int tipc_link_fsm_evt(struct tipc_link *l, int evt);
bool tipc_link_is_up(struct tipc_link *l);
*slot0 = bearer_id;
*slot1 = bearer_id;
tipc_node_fsm_evt(n, SELF_ESTABL_CONTACT_EVT);
- n->failover_sent = false;
n->action_flags |= TIPC_NOTIFY_NODE_UP;
tipc_link_set_active(nl, true);
tipc_bcast_add_peer(n->net, nl, xmitq);
}
/**
+ * tipc_node_link_failover() - start failover in case "half-failover"
+ *
+ * This function is only called in a very special situation where link
+ * failover can be already started on peer node but not on this node.
+ * This can happen when e.g.
+ * 1. Both links <1A-2A>, <1B-2B> down
+ * 2. Link endpoint 2A up, but 1A still down (e.g. due to network
+ * disturbance, wrong session, etc.)
+ * 3. Link <1B-2B> up
+ * 4. Link endpoint 2A down (e.g. due to link tolerance timeout)
+ * 5. Node B starts failover onto link <1B-2B>
+ *
+ * ==> Node A does never start link/node failover!
+ *
+ * @n: tipc node structure
+ * @l: link peer endpoint failingover (- can be NULL)
+ * @tnl: tunnel link
+ * @xmitq: queue for messages to be xmited on tnl link later
+ */
+static void tipc_node_link_failover(struct tipc_node *n, struct tipc_link *l,
+ struct tipc_link *tnl,
+ struct sk_buff_head *xmitq)
+{
+ /* Avoid to be "self-failover" that can never end */
+ if (!tipc_link_is_up(tnl))
+ return;
+
+ tipc_link_fsm_evt(tnl, LINK_SYNCH_END_EVT);
+ tipc_node_fsm_evt(n, NODE_SYNCH_END_EVT);
+
+ n->sync_point = tipc_link_rcv_nxt(tnl) + (U16_MAX / 2 - 1);
+ tipc_link_failover_prepare(l, tnl, xmitq);
+
+ if (l)
+ tipc_link_fsm_evt(l, LINK_FAILOVER_BEGIN_EVT);
+ tipc_node_fsm_evt(n, NODE_FAILOVER_BEGIN_EVT);
+}
+
+/**
* __tipc_node_link_down - handle loss of link
*/
static void __tipc_node_link_down(struct tipc_node *n, int *bearer_id,
tipc_skb_queue_splice_tail_init(tipc_link_inputq(pl),
tipc_link_inputq(l));
}
+
/* If parallel link was already down, and this happened before
- * the tunnel link came up, FAILOVER was never sent. Ensure that
- * FAILOVER is sent to get peer out of NODE_FAILINGOVER state.
+ * the tunnel link came up, node failover was never started.
+ * Ensure that a FAILOVER_MSG is sent to get peer out of
+ * NODE_FAILINGOVER state, also this node must accept
+ * TUNNEL_MSGs from peer.
*/
- if (n->state != NODE_FAILINGOVER && !n->failover_sent) {
- tipc_link_create_dummy_tnl_msg(l, xmitq);
- n->failover_sent = true;
- }
+ if (n->state != NODE_FAILINGOVER)
+ tipc_node_link_failover(n, pl, l, xmitq);
+
/* If pkts arrive out of order, use lowest calculated syncpt */
if (less(syncpt, n->sync_point))
n->sync_point = syncpt;