/*
* net/tipc/link.c: TIPC link code
*
- * Copyright (c) 1996-2007, 2012, Ericsson AB
+ * Copyright (c) 1996-2007, 2012-2014, Ericsson AB
* Copyright (c) 2004-2007, 2010-2013, Wind River Systems
* All rights reserved.
*
static void link_handle_out_of_seq_msg(struct tipc_link *l_ptr,
struct sk_buff *buf);
static void link_recv_proto_msg(struct tipc_link *l_ptr, struct sk_buff *buf);
-static int link_recv_changeover_msg(struct tipc_link **l_ptr,
- struct sk_buff **buf);
+static int tipc_link_tunnel_rcv(struct tipc_link **l_ptr,
+ struct sk_buff **buf);
static void link_set_supervision_props(struct tipc_link *l_ptr, u32 tolerance);
static int link_send_sections_long(struct tipc_port *sender,
struct iovec const *msg_sect,
static void link_state_event(struct tipc_link *l_ptr, u32 event);
static void link_reset_statistics(struct tipc_link *l_ptr);
static void link_print(struct tipc_link *l_ptr, const char *str);
-static void link_start(struct tipc_link *l_ptr);
static int link_send_long_buf(struct tipc_link *l_ptr, struct sk_buff *buf);
static void tipc_link_send_sync(struct tipc_link *l);
static void tipc_link_recv_sync(struct tipc_node *n, struct sk_buff *buf);
tipc_node_attach_link(n_ptr, l_ptr);
- k_init_timer(&l_ptr->timer, (Handler)link_timeout, (unsigned long)l_ptr);
+ k_init_timer(&l_ptr->timer, (Handler)link_timeout,
+ (unsigned long)l_ptr);
list_add_tail(&l_ptr->link_list, &b_ptr->links);
- tipc_k_signal((Handler)link_start, (unsigned long)l_ptr);
+
+ link_state_event(l_ptr, STARTING_EVT);
return l_ptr;
}
tipc_node_lock(l_ptr->owner);
tipc_link_reset(l_ptr);
tipc_node_detach_link(l_ptr->owner, l_ptr);
- tipc_link_stop(l_ptr);
+ tipc_link_purge_queues(l_ptr);
list_del_init(&l_ptr->link_list);
tipc_node_unlock(l_ptr->owner);
k_term_timer(&l_ptr->timer);
kfree(l_ptr);
}
-static void link_start(struct tipc_link *l_ptr)
-{
- tipc_node_lock(l_ptr->owner);
- link_state_event(l_ptr, STARTING_EVT);
- tipc_node_unlock(l_ptr->owner);
-}
/**
* link_schedule_port - schedule port for deferred sending
}
/**
- * tipc_link_stop - purge all inbound and outbound messages associated with link
+ * tipc_link_purge_queues - purge all pkt queues associated with link
* @l_ptr: pointer to link
*/
-void tipc_link_stop(struct tipc_link *l_ptr)
+void tipc_link_purge_queues(struct tipc_link *l_ptr)
{
kfree_skb_list(l_ptr->oldest_deferred_in);
kfree_skb_list(l_ptr->first_out);
tipc_node_link_down(l_ptr->owner, l_ptr);
tipc_bearer_remove_dest(l_ptr->b_ptr, l_ptr->addr);
- if (was_active_link && tipc_node_active_links(l_ptr->owner) &&
- l_ptr->owner->permit_changeover) {
+ if (was_active_link && tipc_node_active_links(l_ptr->owner)) {
l_ptr->reset_checkpoint = checkpoint;
l_ptr->exp_msg_count = START_CHANGEOVER;
}
}
/**
- * tipc_recv_msg - process TIPC messages arriving from off-node
+ * tipc_rcv - process TIPC packets/messages arriving from off-node
* @head: pointer to message buffer chain
* @tb_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_recv_msg(struct sk_buff *head, struct tipc_bearer *b_ptr)
+void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
{
read_lock_bh(&tipc_net_lock);
while (head) {
continue;
case CHANGEOVER_PROTOCOL:
type = msg_type(msg);
- if (link_recv_changeover_msg(&l_ptr, &buf)) {
+ if (tipc_link_tunnel_rcv(&l_ptr, &buf)) {
msg = buf_msg(buf);
seq_no = msg_seqno(msg);
if (type == ORIGINAL_MSG)
if (tipc_own_addr > msg_prevnode(msg))
l_ptr->b_ptr->net_plane = msg_net_plane(msg);
- l_ptr->owner->permit_changeover = msg_redundant_link(msg);
-
switch (msg_type(msg)) {
case RESET_MSG:
}
-/*
- * tipc_link_tunnel(): Send one message via a link belonging to
- * another bearer. Owner node is locked.
+/* tipc_link_tunnel_xmit(): Tunnel one packet via a link belonging to
+ * a different bearer. Owner node is locked.
*/
-static void tipc_link_tunnel(struct tipc_link *l_ptr,
- struct tipc_msg *tunnel_hdr, struct tipc_msg *msg,
- u32 selector)
+static void tipc_link_tunnel_xmit(struct tipc_link *l_ptr,
+ struct tipc_msg *tunnel_hdr,
+ struct tipc_msg *msg,
+ u32 selector)
{
struct tipc_link *tunnel;
struct sk_buff *buf;
}
-
-/*
- * changeover(): Send whole message queue via the remaining link
- * Owner node is locked.
+/* tipc_link_failover_send_queue(): A link has gone down, but a second
+ * link is still active. We can do failover. Tunnel the failing link's
+ * whole send queue via the remaining link. This way, we don't lose
+ * any packets, and sequence order is preserved for subsequent traffic
+ * sent over the remaining link. Owner node is locked.
*/
-void tipc_link_changeover(struct tipc_link *l_ptr)
+void tipc_link_failover_send_queue(struct tipc_link *l_ptr)
{
u32 msgcount = l_ptr->out_queue_size;
struct sk_buff *crs = l_ptr->first_out;
if (!tunnel)
return;
- if (!l_ptr->owner->permit_changeover) {
- pr_warn("%speer did not permit changeover\n", link_co_err);
- return;
- }
-
tipc_msg_init(&tunnel_hdr, CHANGEOVER_PROTOCOL,
ORIGINAL_MSG, INT_H_SIZE, l_ptr->addr);
msg_set_bearer_id(&tunnel_hdr, l_ptr->peer_bearer_id);
msgcount = msg_msgcnt(msg);
while (msgcount--) {
msg_set_seqno(m, msg_seqno(msg));
- tipc_link_tunnel(l_ptr, &tunnel_hdr, m,
- msg_link_selector(m));
+ tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, m,
+ msg_link_selector(m));
pos += align(msg_size(m));
m = (struct tipc_msg *)pos;
}
} else {
- tipc_link_tunnel(l_ptr, &tunnel_hdr, msg,
- msg_link_selector(msg));
+ tipc_link_tunnel_xmit(l_ptr, &tunnel_hdr, msg,
+ msg_link_selector(msg));
}
crs = crs->next;
}
}
-void tipc_link_send_duplicate(struct tipc_link *l_ptr, struct tipc_link *tunnel)
+/* tipc_link_dup_send_queue(): A second link has become active. Tunnel a
+ * duplicate of the first link's send queue via the new link. This way, we
+ * are guaranteed that currently queued packets from a socket are delivered
+ * before future traffic from the same socket, even if this is using the
+ * new link. The last arriving copy of each duplicate packet is dropped at
+ * the receiving end by the regular protocol check, so packet cardinality
+ * and sequence order is preserved per sender/receiver socket pair.
+ * Owner node is locked.
+ */
+void tipc_link_dup_send_queue(struct tipc_link *l_ptr,
+ struct tipc_link *tunnel)
{
struct sk_buff *iter;
struct tipc_msg tunnel_hdr;
return eb;
}
-/*
- * link_recv_changeover_msg(): Receive tunneled packet sent
- * via other link. Node is locked. Return extracted buffer.
+/* tipc_link_tunnel_rcv(): Receive a tunneled packet, sent
+ * via other link as result of a failover (ORIGINAL_MSG) or
+ * a new active link (DUPLICATE_MSG). Failover packets are
+ * returned to the active link for delivery upwards.
+ * Owner node is locked.
*/
-static int link_recv_changeover_msg(struct tipc_link **l_ptr,
- struct sk_buff **buf)
+static int tipc_link_tunnel_rcv(struct tipc_link **l_ptr,
+ struct sk_buff **buf)
{
struct sk_buff *tunnel_buf = *buf;
struct tipc_link *dest_link;