tipc: merge port message reception into socket reception function

In order to reduce complexity and save a call level during message
reception at port/socket level, we remove the function tipc_port_rcv()
and merge its functionality into tipc_sk_rcv().

Signed-off-by: Jon Maloy <jon.maloy@ericsson.com>
Reviewed-by: Ying Xue <ying.xue@windriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 46 insertions, 59 deletions

diff --git a/net/tipc/link.c b/net/tipc/link.c
index 24d058796cd9..ad2c57f5868d 100644
--- a/net/tipc/link.c
+++ b/net/tipc/link.c
@@ -37,6 +37,7 @@
 #include "core.h"
 #include "link.h"
 #include "port.h"
+#include "socket.h"
 #include "name_distr.h"
 #include "discover.h"
 #include "config.h"
@@ -1590,7 +1591,7 @@ void tipc_rcv(struct sk_buff *head, struct tipc_bearer *b_ptr)
                 case TIPC_HIGH_IMPORTANCE:
                 case TIPC_CRITICAL_IMPORTANCE:
                         tipc_node_unlock(n_ptr);
-                        tipc_port_rcv(buf);
+                        tipc_sk_rcv(buf);
                         continue;
                 case MSG_BUNDLER:
                         l_ptr->stats.recv_bundles++;
diff --git a/net/tipc/net.c b/net/tipc/net.c
index f8fc95d58c0d..f64375e7f99f 100644
--- a/net/tipc/net.c
+++ b/net/tipc/net.c
@@ -39,6 +39,7 @@
 #include "name_distr.h"
 #include "subscr.h"
 #include "port.h"
+#include "socket.h"
 #include "node.h"
 #include "config.h"
 
@@ -141,7 +142,7 @@ void tipc_net_route_msg(struct sk_buff *buf)
                         if (msg_mcast(msg))
                                 tipc_port_mcast_rcv(buf, NULL);
                         else if (msg_destport(msg))
-                                tipc_port_rcv(buf);
+                                tipc_sk_rcv(buf);
                         else
                                 net_route_named_msg(buf);
                         return;
diff --git a/net/tipc/port.c b/net/tipc/port.c
index 5c14c7801ee6..5fd7acce01ea 100644
--- a/net/tipc/port.c
+++ b/net/tipc/port.c
@@ -165,7 +165,7 @@ void tipc_port_mcast_rcv(struct sk_buff *buf, struct tipc_port_list *dp)
                 msg_set_destnode(msg, tipc_own_addr);
                 if (dp->count == 1) {
                         msg_set_destport(msg, dp->ports[0]);
-                        tipc_port_rcv(buf);
+                        tipc_sk_rcv(buf);
                         tipc_port_list_free(dp);
                         return;
                 }
@@ -180,7 +180,7 @@ void tipc_port_mcast_rcv(struct sk_buff *buf, struct tipc_port_list *dp)
                         if ((index == 0) && (cnt != 0))
                                 item = item->next;
                         msg_set_destport(buf_msg(b), item->ports[index]);
-                        tipc_port_rcv(b);
+                        tipc_sk_rcv(b);
                 }
         }
 exit:
@@ -343,7 +343,7 @@ int tipc_reject_msg(struct sk_buff *buf, u32 err)
         /* send returned message & dispose of rejected message */
         src_node = msg_prevnode(msg);
         if (in_own_node(src_node))
-                tipc_port_rcv(rbuf);
+                tipc_sk_rcv(rbuf);
         else
                 tipc_link_xmit(rbuf, src_node, msg_link_selector(rmsg));
 exit:
@@ -754,37 +754,6 @@ int tipc_port_shutdown(u32 ref)
         return tipc_port_disconnect(ref);
 }
 
-/**
- * tipc_port_rcv - receive message from lower layer and deliver to port user
- */
-int tipc_port_rcv(struct sk_buff *buf)
-{
-        struct tipc_port *p_ptr;
-        struct tipc_msg *msg = buf_msg(buf);
-        u32 destport = msg_destport(msg);
-        u32 dsz = msg_data_sz(msg);
-        u32 err;
-
-        /* forward unresolved named message */
-        if (unlikely(!destport)) {
-                tipc_net_route_msg(buf);
-                return dsz;
-        }
-
-        /* validate destination & pass to port, otherwise reject message */
-        p_ptr = tipc_port_lock(destport);
-        if (likely(p_ptr)) {
-                err = tipc_sk_rcv(&tipc_port_to_sock(p_ptr)->sk, buf);
-                tipc_port_unlock(p_ptr);
-                if (likely(!err))
-                        return dsz;
-        } else {
-                err = TIPC_ERR_NO_PORT;
-        }
-
-        return tipc_reject_msg(buf, err);
-}
-
 /*
  *  tipc_port_iovec_rcv: Concatenate and deliver sectioned
  *                       message for this node.
@@ -798,7 +767,7 @@ static int tipc_port_iovec_rcv(struct tipc_port *sender,
 
         res = tipc_msg_build(&sender->phdr, msg_sect, len, MAX_MSG_SIZE, &buf);
         if (likely(buf))
-                tipc_port_rcv(buf);
+                tipc_sk_rcv(buf);
         return res;
 }
 
diff --git a/net/tipc/port.h b/net/tipc/port.h
index 5dfd165df1d7..cf4ca5b1d9a4 100644
--- a/net/tipc/port.h
+++ b/net/tipc/port.h
@@ -135,7 +135,6 @@ int tipc_port_peer_msg(struct tipc_port *p_ptr, struct tipc_msg *msg);
 /*
  * TIPC messaging routines
  */
-int tipc_port_rcv(struct sk_buff *buf);
 
 int tipc_send(struct tipc_port *port,
               struct iovec const *msg_sect,
diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index 249500614568..ac08966f2858 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -1442,39 +1442,56 @@ static int tipc_backlog_rcv(struct sock *sk, struct sk_buff *buf)
 
 /**
  * tipc_sk_rcv - handle incoming message
- * @sk:  socket receiving message
- * @buf: message
- *
- * Called with port lock already taken.
- *
- * Returns TIPC error status code (TIPC_OK if message is not to be rejected)
+ * @buf: buffer containing arriving message
+ * Consumes buffer
+ * Returns 0 if success, or errno: -EHOSTUNREACH
  */
-u32 tipc_sk_rcv(struct sock *sk, struct sk_buff *buf)
+int tipc_sk_rcv(struct sk_buff *buf)
 {
-        struct tipc_sock *tsk = tipc_sk(sk);
-        u32 res;
+        struct tipc_sock *tsk;
+        struct tipc_port *port;
+        struct sock *sk;
+        u32 dport = msg_destport(buf_msg(buf));
+        int err = TIPC_OK;
         uint limit;
-        /*
-         * Process message if socket is unlocked; otherwise add to backlog queue
-         *
-         * This code is based on sk_receive_skb(), but must be distinct from it
-         * since a TIPC-specific filter/reject mechanism is utilized
-         */
+
+        /* Forward unresolved named message */
+        if (unlikely(!dport)) {
+                tipc_net_route_msg(buf);
+                return 0;
+        }
+
+        /* Validate destination */
+        port = tipc_port_lock(dport);
+        if (unlikely(!port)) {
+                err = TIPC_ERR_NO_PORT;
+                goto exit;
+        }
+
+        tsk = tipc_port_to_sock(port);
+        sk = &tsk->sk;
+
+        /* Queue message */
         bh_lock_sock(sk);
+
         if (!sock_owned_by_user(sk)) {
-                res = filter_rcv(sk, buf);
+                err = filter_rcv(sk, buf);
         } else {
                 if (sk->sk_backlog.len == 0)
                         atomic_set(&tsk->dupl_rcvcnt, 0);
                 limit = rcvbuf_limit(sk, buf) + atomic_read(&tsk->dupl_rcvcnt);
                 if (sk_add_backlog(sk, buf, limit))
-                        res = TIPC_ERR_OVERLOAD;
-                else
-                        res = TIPC_OK;
+                        err = TIPC_ERR_OVERLOAD;
         }
+
         bh_unlock_sock(sk);
+        tipc_port_unlock(port);
 
-        return res;
+        if (likely(!err))
+                return 0;
+exit:
+        tipc_reject_msg(buf, err);
+        return -EHOSTUNREACH;
 }
 
 static int tipc_wait_for_connect(struct socket *sock, long *timeo_p)
diff --git a/net/tipc/socket.h b/net/tipc/socket.h
index 86c27cc51e33..3afcd2a70b31 100644
--- a/net/tipc/socket.h
+++ b/net/tipc/socket.h
@@ -69,6 +69,6 @@ static inline void tipc_sock_wakeup(struct tipc_sock *tsk)
         tsk->sk.sk_write_space(&tsk->sk);
 }
 
-u32 tipc_sk_rcv(struct sock *sk, struct sk_buff *buf);
+int tipc_sk_rcv(struct sk_buff *buf);
 
 #endif