1 files changed, 58 insertions, 40 deletions

diff --git a/net/tipc/link.c b/net/tipc/link.c
index c052437a7cfa..35a2da688db1 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -79,19 +79,49 @@ static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = {
 /*
  * Out-of-range value for link session numbers
  */
-#define INVALID_SESSION 0x10000
+#define WILDCARD_SESSION 0x10000
 
-/*
- * Link state events:
+/* State value stored in 'failover_pkts'
  */
-#define  STARTING_EVT    856384768      /* link processing trigger */
-#define  TRAFFIC_MSG_EVT 560815u        /* rx'd ??? */
-#define  SILENCE_EVT     560817u        /* timer dicovered silence from peer */
+#define FIRST_FAILOVER 0xffffu
 
-/*
- * State value stored in 'failover_pkts'
+/* Link FSM states and events:
  */
-#define FIRST_FAILOVER 0xffffu
+enum {
+        WORKING_WORKING,
+        WORKING_UNKNOWN,
+        RESET_RESET,
+        RESET_UNKNOWN
+};
+
+enum {
+        PEER_RESET_EVT    = RESET_MSG,
+        ACTIVATE_EVT      = ACTIVATE_MSG,
+        TRAFFIC_EVT,      /* Any other valid msg from peer */
+        SILENCE_EVT       /* Peer was silent during last timer interval*/
+};
+
+/* Link FSM state checking routines
+ */
+static int link_working_working(struct tipc_link *l)
+{
+        return l->state == WORKING_WORKING;
+}
+
+static int link_working_unknown(struct tipc_link *l)
+{
+        return l->state == WORKING_UNKNOWN;
+}
+
+static int link_reset_unknown(struct tipc_link *l)
+{
+        return l->state == RESET_UNKNOWN;
+}
+
+static int link_reset_reset(struct tipc_link *l)
+{
+        return l->state == RESET_RESET;
+}
 
 static void link_handle_out_of_seq_msg(struct tipc_link *link,
                                        struct sk_buff *skb);
@@ -268,7 +298,7 @@ struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
                 /* note: peer i/f name is updated by reset/activate message */
         memcpy(&l_ptr->media_addr, media_addr, sizeof(*media_addr));
         l_ptr->owner = n_ptr;
-        l_ptr->peer_session = INVALID_SESSION;
+        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;
@@ -297,8 +327,7 @@ struct tipc_link *tipc_link_create(struct tipc_node *n_ptr,
         link_reset_statistics(l_ptr);
         tipc_node_attach_link(n_ptr, l_ptr);
         setup_timer(&l_ptr->timer, link_timeout, (unsigned long)l_ptr);
-        link_state_event(l_ptr, STARTING_EVT);
-
+        link_set_timer(l_ptr, l_ptr->keepalive_intv);
         return l_ptr;
 }
 
@@ -311,7 +340,6 @@ void tipc_link_delete(struct tipc_link *l)
         tipc_link_reset(l);
         if (del_timer(&l->timer))
                 tipc_link_put(l);
-        l->flags |= LINK_STOPPED;
         /* Delete link now, or when timer is finished: */
         tipc_link_reset_fragments(l);
         tipc_node_detach_link(l->owner, l);
@@ -438,7 +466,7 @@ void tipc_link_reset(struct tipc_link *l_ptr)
         msg_set_session(l_ptr->pmsg, ((msg_session(l_ptr->pmsg) + 1) & 0xffff));
 
         /* Link is down, accept any session */
-        l_ptr->peer_session = INVALID_SESSION;
+        l_ptr->peer_session = WILDCARD_SESSION;
 
         /* Prepare for renewed mtu size negotiation */
         l_ptr->mtu = l_ptr->advertised_mtu;
@@ -452,7 +480,7 @@ void tipc_link_reset(struct tipc_link *l_ptr)
         tipc_bearer_remove_dest(owner->net, l_ptr->bearer_id, l_ptr->addr);
 
         if (was_active_link && tipc_node_is_up(l_ptr->owner) && (pl != l_ptr)) {
-                l_ptr->flags |= LINK_FAILINGOVER;
+                l_ptr->exec_mode = TIPC_LINK_BLOCKED;
                 l_ptr->failover_checkpt = l_ptr->rcv_nxt;
                 pl->failover_pkts = FIRST_FAILOVER;
                 pl->failover_checkpt = l_ptr->rcv_nxt;
@@ -496,21 +524,14 @@ static void link_activate(struct tipc_link *link)
 static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
 {
         struct tipc_link *other;
-        unsigned long timer_intv = l_ptr->keepalive_intv;
-
-        if (l_ptr->flags & LINK_STOPPED)
-                return;
-
-        if (!(l_ptr->flags & LINK_STARTED) && (event != STARTING_EVT))
-                return;         /* Not yet. */
 
-        if (l_ptr->flags & LINK_FAILINGOVER)
+        if (l_ptr->exec_mode == TIPC_LINK_BLOCKED)
                 return;
 
         switch (l_ptr->state) {
         case WORKING_WORKING:
                 switch (event) {
-                case TRAFFIC_MSG_EVT:
+                case TRAFFIC_EVT:
                 case ACTIVATE_MSG:
                         l_ptr->silent_intv_cnt = 0;
                         break;
@@ -538,7 +559,7 @@ static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
                 break;
         case WORKING_UNKNOWN:
                 switch (event) {
-                case TRAFFIC_MSG_EVT:
+                case TRAFFIC_EVT:
                 case ACTIVATE_MSG:
                         l_ptr->state = WORKING_WORKING;
                         l_ptr->silent_intv_cnt = 0;
@@ -576,7 +597,7 @@ static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
                 break;
         case RESET_UNKNOWN:
                 switch (event) {
-                case TRAFFIC_MSG_EVT:
+                case TRAFFIC_EVT:
                         break;
                 case ACTIVATE_MSG:
                         other = node_active_link(l_ptr->owner, 0);
@@ -593,10 +614,6 @@ static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
                         tipc_link_proto_xmit(l_ptr, ACTIVATE_MSG,
                                              1, 0, 0, 0);
                         break;
-                case STARTING_EVT:
-                        l_ptr->flags |= LINK_STARTED;
-                        link_set_timer(l_ptr, timer_intv);
-                        break;
                 case SILENCE_EVT:
                         tipc_link_proto_xmit(l_ptr, RESET_MSG, 0, 0, 0, 0);
                         break;
@@ -606,7 +623,7 @@ static void link_state_event(struct tipc_link *l_ptr, unsigned int event)
                 break;
         case RESET_RESET:
                 switch (event) {
-                case TRAFFIC_MSG_EVT:
+                case TRAFFIC_EVT:
                 case ACTIVATE_MSG:
                         other = node_active_link(l_ptr->owner, 0);
                         if (other && link_working_unknown(other))
@@ -975,7 +992,7 @@ static bool link_synch(struct tipc_link *l)
         if (skb_queue_len(pl->inputq) > post_synch)
                 return false;
 synched:
-        l->flags &= ~LINK_SYNCHING;
+        l->exec_mode = TIPC_LINK_OPEN;
         return true;
 }
 
@@ -1091,7 +1108,7 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b_ptr)
                         }
 
                         /* Traffic message. Conditionally activate link */
-                        link_state_event(l_ptr, TRAFFIC_MSG_EVT);
+                        link_state_event(l_ptr, TRAFFIC_EVT);
 
                         if (link_working_working(l_ptr)) {
                                 /* Re-insert buffer in front of queue */
@@ -1112,7 +1129,8 @@ void tipc_rcv(struct net *net, struct sk_buff *skb, struct tipc_bearer *b_ptr)
                 l_ptr->silent_intv_cnt = 0;
 
                 /* Synchronize with parallel link if applicable */
-                if (unlikely((l_ptr->flags & LINK_SYNCHING) && !msg_dup(msg))) {
+                if (unlikely((l_ptr->exec_mode == TIPC_LINK_TUNNEL) &&
+                             !msg_dup(msg))) {
                         if (!link_synch(l_ptr))
                                 goto unlock;
                 }
@@ -1193,7 +1211,7 @@ static void tipc_link_input(struct tipc_link *link, struct sk_buff *skb)
         switch (msg_user(msg)) {
         case TUNNEL_PROTOCOL:
                 if (msg_dup(msg)) {
-                        link->flags |= LINK_SYNCHING;
+                        link->exec_mode = TIPC_LINK_TUNNEL;
                         link->synch_point = msg_seqno(msg_get_wrapped(msg));
                         kfree_skb(skb);
                         break;
@@ -1315,7 +1333,7 @@ void tipc_link_proto_xmit(struct tipc_link *l_ptr, u32 msg_typ, int probe_msg,
         u16 last_rcv;
 
         /* Don't send protocol message during link failover */
-        if (l_ptr->flags & LINK_FAILINGOVER)
+        if (l_ptr->exec_mode == TIPC_LINK_BLOCKED)
                 return;
 
         /* Abort non-RESET send if communication with node is prohibited */
@@ -1390,7 +1408,7 @@ static void tipc_link_proto_rcv(struct tipc_link *l_ptr,
         u32 msg_tol;
         struct tipc_msg *msg = buf_msg(buf);
 
-        if (l_ptr->flags & LINK_FAILINGOVER)
+        if (l_ptr->exec_mode == TIPC_LINK_BLOCKED)
                 goto exit;
 
         if (l_ptr->net_plane != msg_net_plane(msg))
@@ -1401,7 +1419,7 @@ static void tipc_link_proto_rcv(struct tipc_link *l_ptr,
 
         case RESET_MSG:
                 if (!link_working_unknown(l_ptr) &&
-                    (l_ptr->peer_session != INVALID_SESSION)) {
+                    (l_ptr->peer_session != WILDCARD_SESSION)) {
                         if (less_eq(msg_session(msg), l_ptr->peer_session))
                                 break; /* duplicate or old reset: ignore */
                 }
@@ -1465,7 +1483,7 @@ static void tipc_link_proto_rcv(struct tipc_link *l_ptr,
                 /* Record reception; force mismatch at next timeout: */
                 l_ptr->silent_intv_cnt = 0;
 
-                link_state_event(l_ptr, TRAFFIC_MSG_EVT);
+                link_state_event(l_ptr, TRAFFIC_EVT);
                 l_ptr->stats.recv_states++;
                 if (link_reset_unknown(l_ptr))
                         break;
@@ -1704,7 +1722,7 @@ static bool tipc_link_failover_rcv(struct tipc_link *link,
         }
 exit:
         if (!link->failover_pkts && pl)
-                pl->flags &= ~LINK_FAILINGOVER;
+                pl->exec_mode = TIPC_LINK_OPEN;
         kfree_skb(*skb);
         *skb = iskb;
         return *skb;