tipc: create TIPC_DISCONNECTING as a new sk_state

In this commit, we create a new tipc socket state TIPC_DISCONNECTING in
sk_state. TIPC_DISCONNECTING is replacing the socket connection status
update using SS_DISCONNECTING.
TIPC_DISCONNECTING is set for connection oriented sockets at:
- tipc_shutdown()
- connection probe timeout
- when we receive an error message on the connection.

There is no functional change in this commit.

Signed-off-by: Parthasarathy Bhuvaragan <parthasarathy.bhuvaragan@ericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 24 insertions, 15 deletions

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index b14dd2549980..a48c0c0676cf 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -54,6 +54,7 @@ enum {
         TIPC_LISTEN = TCP_LISTEN,
         TIPC_ESTABLISHED = TCP_ESTABLISHED,
         TIPC_OPEN = TCP_CLOSE,
+        TIPC_DISCONNECTING = TCP_CLOSE_WAIT,
 };
 
 /**
@@ -362,10 +363,14 @@ static int tipc_set_sk_state(struct sock *sk, int state)
                 break;
         case TIPC_ESTABLISHED:
                 if (oldstate == SS_CONNECTING ||
-                    oldstate == SS_UNCONNECTED ||
                     oldsk_state == TIPC_OPEN)
                         res = 0;
                 break;
+        case TIPC_DISCONNECTING:
+                if (oldstate == SS_CONNECTING ||
+                    oldsk_state == TIPC_ESTABLISHED)
+                        res = 0;
+                break;
         }
 
         if (!res)
@@ -621,13 +626,14 @@ static int tipc_getname(struct socket *sock, struct sockaddr *uaddr,
                         int *uaddr_len, int peer)
 {
         struct sockaddr_tipc *addr = (struct sockaddr_tipc *)uaddr;
-        struct tipc_sock *tsk = tipc_sk(sock->sk);
+        struct sock *sk = sock->sk;
+        struct tipc_sock *tsk = tipc_sk(sk);
         struct tipc_net *tn = net_generic(sock_net(sock->sk), tipc_net_id);
 
         memset(addr, 0, sizeof(*addr));
         if (peer) {
                 if ((sock->state != SS_CONNECTED) &&
-                        ((peer != 2) || (sock->state != SS_DISCONNECTING)))
+                    ((peer != 2) || (sk->sk_state != TIPC_DISCONNECTING)))
                         return -ENOTCONN;
                 addr->addr.id.ref = tsk_peer_port(tsk);
                 addr->addr.id.node = tsk_peer_node(tsk);
@@ -693,6 +699,9 @@ static unsigned int tipc_poll(struct file *file, struct socket *sock,
                             (!skb_queue_empty(&sk->sk_receive_queue)))
                                 mask |= (POLLIN | POLLRDNORM);
                         break;
+                case TIPC_DISCONNECTING:
+                        mask = (POLLIN | POLLRDNORM | POLLHUP);
+                        break;
                 case TIPC_LISTEN:
                         if (!skb_queue_empty(&sk->sk_receive_queue))
                                 mask |= (POLLIN | POLLRDNORM);
@@ -1028,7 +1037,7 @@ static int tipc_wait_for_sndpkt(struct socket *sock, long *timeo_p)
                 int err = sock_error(sk);
                 if (err)
                         return err;
-                if (sock->state == SS_DISCONNECTING)
+                if (sk->sk_state == TIPC_DISCONNECTING)
                         return -EPIPE;
                 else if (sock->state != SS_CONNECTED)
                         return -ENOTCONN;
@@ -1098,7 +1107,7 @@ static int __tipc_send_stream(struct socket *sock, struct msghdr *m, size_t dsz)
                 return -EMSGSIZE;
 
         if (unlikely(sock->state != SS_CONNECTED)) {
-                if (sock->state == SS_DISCONNECTING)
+                if (sk->sk_state == TIPC_DISCONNECTING)
                         return -EPIPE;
                 else
                         return -ENOTCONN;
@@ -1626,7 +1635,7 @@ static bool filter_connect(struct tipc_sock *tsk, struct sk_buff *skb)
                         return false;
 
                 if (unlikely(msg_errcode(hdr))) {
-                        sock->state = SS_DISCONNECTING;
+                        tipc_set_sk_state(sk, TIPC_DISCONNECTING);
                         /* Let timer expire on it's own */
                         tipc_node_remove_conn(net, tsk_peer_node(tsk),
                                               tsk->portid);
@@ -1641,13 +1650,13 @@ static bool filter_connect(struct tipc_sock *tsk, struct sk_buff *skb)
                         return false;
 
                 if (unlikely(msg_errcode(hdr))) {
-                        sock->state = SS_DISCONNECTING;
+                        tipc_set_sk_state(sk, TIPC_DISCONNECTING);
                         sk->sk_err = ECONNREFUSED;
                         return true;
                 }
 
                 if (unlikely(!msg_isdata(hdr))) {
-                        sock->state = SS_DISCONNECTING;
+                        tipc_set_sk_state(sk, TIPC_DISCONNECTING);
                         sk->sk_err = EINVAL;
                         return true;
                 }
@@ -1674,6 +1683,7 @@ static bool filter_connect(struct tipc_sock *tsk, struct sk_buff *skb)
 
         switch (sk->sk_state) {
         case TIPC_OPEN:
+        case TIPC_DISCONNECTING:
                 break;
         case TIPC_LISTEN:
                 /* Accept only SYN message */
@@ -2195,9 +2205,7 @@ static int tipc_shutdown(struct socket *sock, int how)
 
         lock_sock(sk);
 
-        switch (sock->state) {
-        case SS_CONNECTING:
-        case SS_CONNECTED:
+        if (sock->state == SS_CONNECTING || sock->state == SS_CONNECTED) {
 
 restart:
                 dnode = tsk_peer_node(tsk);
@@ -2218,11 +2226,12 @@ restart:
                         if (skb)
                                 tipc_node_xmit_skb(net, skb, dnode, tsk->portid);
                 }
-                sock->state = SS_DISCONNECTING;
+                tipc_set_sk_state(sk, TIPC_DISCONNECTING);
                 tipc_node_remove_conn(net, dnode, tsk->portid);
-                /* fall through */
+        }
 
-        case SS_DISCONNECTING:
+        switch (sk->sk_state) {
+        case TIPC_DISCONNECTING:
 
                 /* Discard any unreceived messages */
                 __skb_queue_purge(&sk->sk_receive_queue);
@@ -2258,7 +2267,7 @@ static void tipc_sk_timeout(unsigned long data)
 
         if (tsk->probe_unacked) {
                 if (!sock_owned_by_user(sk)) {
-                        sk->sk_socket->state = SS_DISCONNECTING;
+                        tipc_set_sk_state(sk, TIPC_DISCONNECTING);
                         tipc_node_remove_conn(sock_net(sk), tsk_peer_node(tsk),
                                               tsk_peer_port(tsk));
                         sk->sk_state_change(sk);