/* Link FSM states and events:
*/
enum {
- WORKING_WORKING,
- WORKING_UNKNOWN,
- RESET_RESET,
- RESET_UNKNOWN
+ TIPC_LINK_WORKING,
+ TIPC_LINK_PROBING,
+ TIPC_LINK_RESETTING,
+ TIPC_LINK_ESTABLISHING
};
enum {
/* Link FSM state checking routines
*/
-static int link_working_working(struct tipc_link *l)
+static int link_working(struct tipc_link *l)
{
- return l->state == WORKING_WORKING;
+ return l->state == TIPC_LINK_WORKING;
}
-static int link_working_unknown(struct tipc_link *l)
+static int link_probing(struct tipc_link *l)
{
- return l->state == WORKING_UNKNOWN;
+ return l->state == TIPC_LINK_PROBING;
}
-static int link_reset_unknown(struct tipc_link *l)
+static int link_resetting(struct tipc_link *l)
{
- return l->state == RESET_UNKNOWN;
+ return l->state == TIPC_LINK_RESETTING;
}
-static int link_reset_reset(struct tipc_link *l)
+static int link_establishing(struct tipc_link *l)
{
- return l->state == RESET_RESET;
+ return l->state == TIPC_LINK_ESTABLISHING;
}
static void link_handle_out_of_seq_msg(struct tipc_link *link,
static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb);
static bool tipc_link_failover_rcv(struct tipc_link *l, struct sk_buff **skb);
static void link_set_timer(struct tipc_link *link, unsigned long time);
+static void link_activate(struct tipc_link *link);
+
/*
* Simple link routines
*/
{
if (!l_ptr)
return 0;
- return link_working_working(l_ptr) || link_working_unknown(l_ptr);
+ return link_working(l_ptr) || link_probing(l_ptr);
}
int tipc_link_is_active(struct tipc_link *l)
}
/* do all other link processing performed on a periodic basis */
- if (l_ptr->silent_intv_cnt || tipc_bclink_acks_missing(l_ptr->owner))
+ if (l_ptr->silent_intv_cnt)
link_state_event(l_ptr, SILENCE_EVT);
+ else if (link_working(l_ptr) && tipc_bclink_acks_missing(l_ptr->owner))
+ tipc_link_proto_xmit(l_ptr, STATE_MSG, 0, 0, 0, 0);
+
l_ptr->silent_intv_cnt++;
if (skb_queue_len(&l_ptr->backlogq))
tipc_link_push_packets(l_ptr);
l_ptr->peer_session = WILDCARD_SESSION;
l_ptr->bearer_id = b_ptr->identity;
link_set_supervision_props(l_ptr, b_ptr->tolerance);
- l_ptr->state = RESET_UNKNOWN;
+ l_ptr->state = TIPC_LINK_RESETTING;
l_ptr->pmsg = (struct tipc_msg *)&l_ptr->proto_msg;
msg = l_ptr->pmsg;
rcu_read_unlock();
}
+/**
+ * tipc_link_fsm_evt - link finite state machine
+ * @l: pointer to link
+ * @evt: state machine event to be processed
+ * @xmitq: queue to prepend created protocol message, if any
+ */
+static int tipc_link_fsm_evt(struct tipc_link *l, int evt,
+ struct sk_buff_head *xmitq)
+{
+ int mtyp = 0, rc = 0;
+ struct tipc_link *pl;
+ enum {
+ LINK_RESET = 1,
+ LINK_ACTIVATE = (1 << 1),
+ SND_PROBE = (1 << 2),
+ SND_STATE = (1 << 3),
+ SND_RESET = (1 << 4),
+ SND_ACTIVATE = (1 << 5)
+ } actions = 0;
+
+ if (l->exec_mode == TIPC_LINK_BLOCKED)
+ return rc;
+
+ switch (l->state) {
+ case TIPC_LINK_WORKING:
+ switch (evt) {
+ case TRAFFIC_EVT:
+ case ACTIVATE_EVT:
+ break;
+ case SILENCE_EVT:
+ l->state = TIPC_LINK_PROBING;
+ actions |= SND_PROBE;
+ break;
+ case PEER_RESET_EVT:
+ actions |= LINK_RESET | SND_ACTIVATE;
+ break;
+ default:
+ pr_debug("%s%u WORKING\n", link_unk_evt, evt);
+ }
+ break;
+ case TIPC_LINK_PROBING:
+ switch (evt) {
+ case TRAFFIC_EVT:
+ case ACTIVATE_EVT:
+ l->state = TIPC_LINK_WORKING;
+ break;
+ case PEER_RESET_EVT:
+ actions |= LINK_RESET | SND_ACTIVATE;
+ break;
+ case SILENCE_EVT:
+ if (l->silent_intv_cnt <= l->abort_limit) {
+ actions |= SND_PROBE;
+ break;
+ }
+ actions |= LINK_RESET | SND_RESET;
+ break;
+ default:
+ pr_err("%s%u PROBING\n", link_unk_evt, evt);
+ }
+ break;
+ case TIPC_LINK_RESETTING:
+ switch (evt) {
+ case TRAFFIC_EVT:
+ break;
+ case ACTIVATE_EVT:
+ pl = node_active_link(l->owner, 0);
+ if (pl && link_probing(pl))
+ break;
+ actions |= LINK_ACTIVATE;
+ if (l->owner->working_links == 1)
+ tipc_link_sync_xmit(l);
+ break;
+ case PEER_RESET_EVT:
+ l->state = TIPC_LINK_ESTABLISHING;
+ actions |= SND_ACTIVATE;
+ break;
+ case SILENCE_EVT:
+ actions |= SND_RESET;
+ break;
+ default:
+ pr_err("%s%u in RESETTING\n", link_unk_evt, evt);
+ }
+ break;
+ case TIPC_LINK_ESTABLISHING:
+ switch (evt) {
+ case TRAFFIC_EVT:
+ case ACTIVATE_EVT:
+ pl = node_active_link(l->owner, 0);
+ if (pl && link_probing(pl))
+ break;
+ actions |= LINK_ACTIVATE;
+ if (l->owner->working_links == 1)
+ tipc_link_sync_xmit(l);
+ break;
+ case PEER_RESET_EVT:
+ break;
+ case SILENCE_EVT:
+ actions |= SND_ACTIVATE;
+ break;
+ default:
+ pr_err("%s%u ESTABLISHING\n", link_unk_evt, evt);
+ }
+ break;
+ default:
+ pr_err("Unknown link state %u/%u\n", l->state, evt);
+ }
+
+ /* Perform actions as decided by FSM */
+ if (actions & LINK_RESET) {
+ l->exec_mode = TIPC_LINK_BLOCKED;
+ rc |= TIPC_LINK_DOWN_EVT;
+ }
+ if (actions & LINK_ACTIVATE) {
+ l->exec_mode = TIPC_LINK_OPEN;
+ rc |= TIPC_LINK_UP_EVT;
+ }
+ if (actions & (SND_STATE | SND_PROBE))
+ mtyp = STATE_MSG;
+ if (actions & SND_RESET)
+ mtyp = RESET_MSG;
+ if (actions & SND_ACTIVATE)
+ mtyp = ACTIVATE_MSG;
+ if (actions & (SND_PROBE | SND_STATE | SND_RESET | SND_ACTIVATE))
+ tipc_link_build_proto_msg(l, mtyp, actions & SND_PROBE,
+ 0, 0, 0, xmitq);
+ return rc;
+}
+
/**
* link_schedule_user - schedule a message sender for wakeup after congestion
* @link: congested link
/* Prepare for renewed mtu size negotiation */
l_ptr->mtu = l_ptr->advertised_mtu;
- l_ptr->state = RESET_UNKNOWN;
+ l_ptr->state = TIPC_LINK_RESETTING;
- if ((prev_state == RESET_UNKNOWN) || (prev_state == RESET_RESET))
+ if ((prev_state == TIPC_LINK_RESETTING) ||
+ (prev_state == TIPC_LINK_ESTABLISHING))
return;
tipc_node_link_down(l_ptr->owner, l_ptr->bearer_id);
link->rcv_nxt = 1;
link->stats.recv_info = 1;
link->silent_intv_cnt = 0;
+ link->state = TIPC_LINK_WORKING;
+ link->exec_mode = TIPC_LINK_OPEN;
tipc_node_link_up(node, link->bearer_id);
tipc_bearer_add_dest(node->net, link->bearer_id, link->addr);
}
* @l_ptr: pointer to link
* @event: state machine event to process
*/
-static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
+static void link_state_event(struct tipc_link *l, unsigned int evt)
{
- struct tipc_link *other;
+ int rc;
+ struct sk_buff_head xmitq;
+ struct sk_buff *skb;
- if (l_ptr->exec_mode == TIPC_LINK_BLOCKED)
+ if (l->exec_mode == TIPC_LINK_BLOCKED)
return;
- switch (l_ptr->state) {
- case WORKING_WORKING:
- switch (event) {
- case TRAFFIC_EVT:
- case ACTIVATE_MSG:
- l_ptr->silent_intv_cnt = 0;
- break;
- case SILENCE_EVT:
- if (!l_ptr->silent_intv_cnt) {
- if (tipc_bclink_acks_missing(l_ptr->owner))
- tipc_link_proto_xmit(l_ptr, STATE_MSG,
- 0, 0, 0, 0);
- break;
- }
- l_ptr->state = WORKING_UNKNOWN;
- tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
- break;
- case RESET_MSG:
- pr_debug("%s<%s>, requested by peer\n",
- link_rst_msg, l_ptr->name);
- tipc_link_reset(l_ptr);
- l_ptr->state = RESET_RESET;
- tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
- 0, 0, 0, 0);
- break;
- default:
- pr_debug("%s%u in WW state\n", link_unk_evt, event);
- }
- break;
- case WORKING_UNKNOWN:
- switch (event) {
- case TRAFFIC_EVT:
- case ACTIVATE_MSG:
- l_ptr->state = WORKING_WORKING;
- l_ptr->silent_intv_cnt = 0;
- break;
- case RESET_MSG:
- pr_debug("%s<%s>, requested by peer while probing\n",
- link_rst_msg, l_ptr->name);
- tipc_link_reset(l_ptr);
- l_ptr->state = RESET_RESET;
- tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
- 0, 0, 0, 0);
- break;
- case SILENCE_EVT:
- if (!l_ptr->silent_intv_cnt) {
- l_ptr->state = WORKING_WORKING;
- if (tipc_bclink_acks_missing(l_ptr->owner))
- tipc_link_proto_xmit(l_ptr, STATE_MSG,
- 0, 0, 0, 0);
- } else if (l_ptr->silent_intv_cnt <
- l_ptr->abort_limit) {
- tipc_link_proto_xmit(l_ptr, STATE_MSG,
- 1, 0, 0, 0);
- } else { /* Link has failed */
- pr_debug("%s<%s>, peer not responding\n",
- link_rst_msg, l_ptr->name);
- tipc_link_reset(l_ptr);
- l_ptr->state = RESET_UNKNOWN;
- tipc_link_proto_xmit(l_ptr, RESET_MSG,
- 0, 0, 0, 0);
- }
- break;
- default:
- pr_err("%s%u in WU state\n", link_unk_evt, event);
- }
- break;
- case RESET_UNKNOWN:
- switch (event) {
- case TRAFFIC_EVT:
- break;
- case ACTIVATE_MSG:
- other = node_active_link(l_ptr->owner, 0);
- if (other && link_working_unknown(other))
- break;
- l_ptr->state = WORKING_WORKING;
- link_activate(l_ptr);
- tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
- if (l_ptr->owner->working_links == 1)
- tipc_link_sync_xmit(l_ptr);
- break;
- case RESET_MSG:
- l_ptr->state = RESET_RESET;
- tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
- 1, 0, 0, 0);
- break;
- case SILENCE_EVT:
- tipc_link_proto_xmit(l_ptr, RESET_MSG, 0, 0, 0, 0);
- break;
- default:
- pr_err("%s%u in RU state\n", link_unk_evt, event);
- }
- break;
- case RESET_RESET:
- switch (event) {
- case TRAFFIC_EVT:
- case ACTIVATE_MSG:
- other = node_active_link(l_ptr->owner, 0);
- if (other && link_working_unknown(other))
- break;
- l_ptr->state = WORKING_WORKING;
- link_activate(l_ptr);
- tipc_link_proto_xmit(l_ptr, STATE_MSG, 1, 0, 0, 0);
- if (l_ptr->owner->working_links == 1)
- tipc_link_sync_xmit(l_ptr);
- break;
- case RESET_MSG:
- break;
- case SILENCE_EVT:
- tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
- 0, 0, 0, 0);
- break;
- default:
- pr_err("%s%u in RR state\n", link_unk_evt, event);
- }
- break;
- default:
- pr_err("Unknown link state %u/%u\n", l_ptr->state, event);
- }
+ __skb_queue_head_init(&xmitq);
+
+ rc = tipc_link_fsm_evt(l, evt, &xmitq);
+
+ if (rc & TIPC_LINK_UP_EVT)
+ link_activate(l);
+
+ if (rc & TIPC_LINK_DOWN_EVT)
+ tipc_link_reset(l);
+
+ skb = __skb_dequeue(&xmitq);
+ if (!skb)
+ return;
+ tipc_bearer_send(l->owner->net, l->bearer_id, skb, &l->media_addr);
}
/**
link_prepare_wakeup(l_ptr);
/* Process the incoming packet */
- if (unlikely(!link_working_working(l_ptr))) {
+ 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);
/* Traffic message. Conditionally activate link */
link_state_event(l_ptr, TRAFFIC_EVT);
- if (link_working_working(l_ptr)) {
+ if (link_working(l_ptr)) {
/* Re-insert buffer in front of queue */
__skb_queue_head(&head, skb);
skb = NULL;
goto unlock;
}
- /* Link is now in state WORKING_WORKING */
+ /* 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);
switch (msg_type(msg)) {
case RESET_MSG:
- if (!link_working_unknown(l_ptr) &&
+ if (!link_probing(l_ptr) &&
(l_ptr->peer_session != WILDCARD_SESSION)) {
if (less_eq(msg_session(msg), l_ptr->peer_session))
break; /* duplicate or old reset: ignore */
}
- if (!msg_redundant_link(msg) && (link_working_working(l_ptr) ||
- link_working_unknown(l_ptr))) {
- /*
- * peer has lost contact -- don't allow peer's links
+ if (!msg_redundant_link(msg) && (link_working(l_ptr) ||
+ link_probing(l_ptr))) {
+ /* peer has lost contact -- don't allow peer's links
* to reactivate before we recognize loss & clean up
*/
l_ptr->owner->action_flags |= TIPC_WAIT_OWN_LINKS_DOWN;
link_state_event(l_ptr, TRAFFIC_EVT);
l_ptr->stats.recv_states++;
- if (link_reset_unknown(l_ptr))
+ if (link_resetting(l_ptr))
break;
if (less_eq(l_ptr->rcv_nxt, msg_next_sent(msg)))
pr_info("%s Link %x<%s>:", str, l_ptr->addr, b_ptr->name);
rcu_read_unlock();
- if (link_working_unknown(l_ptr))
- pr_cont(":WU\n");
- else if (link_reset_reset(l_ptr))
- pr_cont(":RR\n");
- else if (link_reset_unknown(l_ptr))
- pr_cont(":RU\n");
- else if (link_working_working(l_ptr))
- pr_cont(":WW\n");
+ if (link_probing(l_ptr))
+ pr_cont(":P\n");
+ else if (link_establishing(l_ptr))
+ pr_cont(":E\n");
+ else if (link_resetting(l_ptr))
+ pr_cont(":R\n");
+ else if (link_working(l_ptr))
+ pr_cont(":W\n");
else
pr_cont("\n");
}
projects / cascardo / linux.git / blobdiff