ethernet: Factor out ether_characterize()

diff --git a/sys/net/if_ethersubr.c b/sys/net/if_ethersubr.c
index 9bbfce7..c666ab4 100644 (file)
--- a/sys/net/if_ethersubr.c
+++ b/sys/net/if_ethersubr.c
@@ -127,6 +127,7 @@ static int ether_output(struct ifnet *, struct mbuf *, struct sockaddr *,
                        struct rtentry *);
 static void ether_restore_header(struct mbuf **, const struct ether_header *,
                                 const struct ether_header *);
+static int ether_characterize(struct mbuf **);
 
 /*
  * if_bridge support
@@ -1538,8 +1539,6 @@ void
 ether_input_chain(struct ifnet *ifp, struct mbuf *m, const struct pktinfo *pi,
                  struct mbuf_chain *chain)
 {
-       struct ether_header *eh;
-       uint16_t ether_type;
        int isr;
 
        M_ASSERTPKTHDR(m);
@@ -1565,6 +1564,8 @@ ether_input_chain(struct ifnet *ifp, struct mbuf *m, const struct pktinfo *pi,
        ifp->if_ibytes += m->m_pkthdr.len;
 
        if (ifp->if_flags & IFF_MONITOR) {
+               struct ether_header *eh;
+
                eh = mtod(m, struct ether_header *);
                if (ETHER_IS_MULTICAST(eh->ether_dhost))
                        ifp->if_imcasts++;
@@ -1618,6 +1619,29 @@ ether_input_chain(struct ifnet *ifp, struct mbuf *m, const struct pktinfo *pi,
                logether(chain_end, ifp);
                return;
        }
+
+       isr = ether_characterize(&m);
+       if (m == NULL) {
+               logether(chain_end, ifp);
+               return;
+       }
+
+       /*
+        * Finally dispatch it
+        */
+       ether_dispatch(isr, m, chain);
+
+       logether(chain_end, ifp);
+}
+
+static int
+ether_characterize(struct mbuf **m0)
+{
+       struct mbuf *m = *m0;
+       struct ether_header *eh;
+       uint16_t ether_type;
+       int isr;
+
        eh = mtod(m, struct ether_header *);
        ether_type = ntohs(eh->ether_type);
 
@@ -1667,6 +1691,8 @@ ether_input_chain(struct ifnet *ifp, struct mbuf *m, const struct pktinfo *pi,
        default:
                /*
                 * NETISR_MAX is an invalid value; it is chosen to let
+                * netisr_characterize() know that we have no clear
+                * idea where this packet should go.
                 */
                isr = NETISR_MAX;
                break;
@@ -1678,17 +1704,9 @@ ether_input_chain(struct ifnet *ifp, struct mbuf *m, const struct pktinfo *pi,
         * thread.
         */
        netisr_characterize(isr, &m, sizeof(struct ether_header));
-       if (m == NULL) {
-               logether(chain_end, ifp);
-               return;
-       }
-
-       /*
-        * Finally dispatch it
-        */
-       ether_dispatch(isr, m, chain);
 
-       logether(chain_end, ifp);
+       *m0 = m;
+       return isr;
 }
 
 MODULE_VERSION(ether, 1);