tipc: enqueue arrived buffers in socket in separate function

The code for enqueuing arriving buffers in the function tipc_sk_rcv()
contains long code lines and currently goes to two indentation levels.
As a cosmetic preparaton for the next commits, we break it out into
a separate function.

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

1 files changed, 31 insertions, 15 deletions

diff --git a/net/tipc/socket.c b/net/tipc/socket.c
index f9cd587e4090..1d98bfcda6f6 100644
--- a/net/tipc/socket.c
+++ b/net/tipc/socket.c
@@ -1765,6 +1765,35 @@ static int tipc_backlog_rcv(struct sock *sk, struct sk_buff *skb)
 }
 
 /**
+ * tipc_sk_enqueue_skb - enqueue buffer to socket or backlog queue
+ * @sk: socket
+ * @skb: pointer to message. Set to NULL if buffer is consumed.
+ * @dnode: if buffer should be forwarded/returned, send to this node
+ *
+ * Caller must hold socket lock
+ *
+ * Returns TIPC_OK (0) or -tipc error code
+ */
+static int tipc_sk_enqueue_skb(struct sock *sk, struct sk_buff **skb)
+{
+        unsigned int lim;
+        atomic_t *dcnt;
+
+        if (unlikely(!*skb))
+                return TIPC_OK;
+        if (!sock_owned_by_user(sk))
+                return filter_rcv(sk, skb);
+        dcnt = &tipc_sk(sk)->dupl_rcvcnt;
+        if (sk->sk_backlog.len)
+                atomic_set(dcnt, 0);
+        lim = rcvbuf_limit(sk, *skb) + atomic_read(dcnt);
+        if (unlikely(sk_add_backlog(sk, *skb, lim)))
+                return -TIPC_ERR_OVERLOAD;
+        *skb = NULL;
+        return TIPC_OK;
+}
+
+/**
  * tipc_sk_rcv - handle incoming message
  * @skb: buffer containing arriving message
  * Consumes buffer
@@ -1776,8 +1805,7 @@ int tipc_sk_rcv(struct net *net, struct sk_buff *skb)
         struct tipc_net *tn;
         struct sock *sk;
         u32 dport = msg_destport(buf_msg(skb));
-        int err = TIPC_OK;
-        uint limit;
+        int err;
         u32 dnode;
 
         /* Validate destination and message */
@@ -1788,20 +1816,8 @@ int tipc_sk_rcv(struct net *net, struct sk_buff *skb)
         }
         sk = &tsk->sk;
 
-        /* Queue message */
         spin_lock_bh(&sk->sk_lock.slock);
-
-        if (!sock_owned_by_user(sk)) {
-                err = filter_rcv(sk, &skb);
-        } else {
-                if (sk->sk_backlog.len == 0)
-                        atomic_set(&tsk->dupl_rcvcnt, 0);
-                limit = rcvbuf_limit(sk, skb) + atomic_read(&tsk->dupl_rcvcnt);
-                if (likely(!sk_add_backlog(sk, skb, limit)))
-                        skb = NULL;
-                else
-                        err = -TIPC_ERR_OVERLOAD;
-        }
+        err = tipc_sk_enqueue_skb(sk, &skb);
         spin_unlock_bh(&sk->sk_lock.slock);
         sock_put(sk);
 exit: