[src/trunk]: src/sys/net Style, make the code more readable, and add a KASSER...

[maxv <maxv%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/3f9cbc1ac6ee
branches:  trunk
changeset: 358742:3f9cbc1ac6ee
user:      maxv <maxv%NetBSD.org@localhost>
date:      Mon Jan 15 11:57:27 2018 +0000

description:
Style, make the code more readable, and add a KASSERT (we expect the mbuf
to have M_PKTHDR set).

diffstat:

 sys/net/if_ethersubr.c |  55 ++++++++++++++++++++++++++++++--------------------
 1 files changed, 33 insertions(+), 22 deletions(-)

diffs (188 lines):

diff -r b118205d4879 -r 3f9cbc1ac6ee sys/net/if_ethersubr.c
--- a/sys/net/if_ethersubr.c    Mon Jan 15 11:27:39 2018 +0000
+++ b/sys/net/if_ethersubr.c    Mon Jan 15 11:57:27 2018 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: if_ethersubr.c,v 1.252 2018/01/15 10:27:51 maxv Exp $  */
+/*     $NetBSD: if_ethersubr.c,v 1.253 2018/01/15 11:57:27 maxv Exp $  */
 
 /*
  * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
@@ -61,7 +61,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_ethersubr.c,v 1.252 2018/01/15 10:27:51 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_ethersubr.c,v 1.253 2018/01/15 11:57:27 maxv Exp $");
 
 #ifdef _KERNEL_OPT
 #include "opt_inet.h"
@@ -566,6 +566,7 @@
 #endif
 
        KASSERT(!cpu_intr_p());
+       KASSERT((m->m_flags & M_PKTHDR) != 0);
 
        if ((ifp->if_flags & IFF_UP) == 0) {
                m_freem(m);
@@ -639,7 +640,7 @@
                    (uint8_t *)&eh->ether_dhost, eh->ether_type) == 0)
                        return;
        }
-#endif /* NCARP > 0 */
+#endif
 
        if ((m->m_flags & (M_BCAST | M_MCAST | M_PROMISC)) == 0 &&
            (ifp->if_flags & IFF_PROMISC) != 0 &&
@@ -656,7 +657,6 @@
 
                eh = mtod(m, struct ether_header *);
                etype = ntohs(eh->ether_type);
-               ehlen = sizeof(*eh);
        }
 
 #if NAGR > 0
@@ -666,7 +666,7 @@
                agr_input(ifp, m);
                return;
        }
-#endif /* NAGR > 0 */
+#endif
 
        /*
         * If VLANs are configured on the interface, check to
@@ -693,48 +693,52 @@
        switch (etype) {
        case ETHERTYPE_VLAN: {
                struct ether_vlan_header *evl = (void *)eh;
+
                /*
                 * If there is a tag of 0, then the VLAN header was probably
                 * just being used to store the priority.  Extract the ether
                 * type, and if IP or IPV6, let them deal with it.
                 */
-               if (m->m_len <= sizeof(*evl)
-                   && EVL_VLANOFTAG(evl->evl_tag) == 0) {
+               if (m->m_len <= sizeof(*evl) &&
+                   EVL_VLANOFTAG(evl->evl_tag) == 0) {
                        etype = ntohs(evl->evl_proto);
                        ehlen = sizeof(*evl);
-                       if ((m->m_flags & M_PROMISC) == 0
-                           && (etype == ETHERTYPE_IP
-                               || etype == ETHERTYPE_IPV6))
+                       if ((m->m_flags & M_PROMISC) == 0 &&
+                           (etype == ETHERTYPE_IP ||
+                            etype == ETHERTYPE_IPV6))
                                break;
                }
+
 #if NVLAN > 0
                /*
                 * vlan_input() will either recursively call ether_input()
                 * or drop the packet.
                 */
-               if (((struct ethercom *)ifp)->ec_nvlans != 0)
+               if (ec->ec_nvlans != 0)
                        vlan_input(ifp, m);
                else
-#endif /* NVLAN > 0 */
+#endif
                        m_freem(m);
+
                return;
        }
+
 #if NPPPOE > 0
        case ETHERTYPE_PPPOEDISC:
                pppoedisc_input(ifp, m);
                return;
+
        case ETHERTYPE_PPPOE:
                pppoe_input(ifp, m);
                return;
-#endif /* NPPPOE > 0 */
+#endif
+
        case ETHERTYPE_SLOWPROTOCOLS: {
                uint8_t subtype;
 
-#if defined(DIAGNOSTIC)
-               if (m->m_pkthdr.len < sizeof(*eh) + sizeof(subtype)) {
-                       panic("ether_input: too short slow protocol packet");
-               }
-#endif
+               KASSERTMSG((m->m_pkthdr.len < sizeof(*eh) + sizeof(subtype)),
+                       "too short slow protocol packet");
+
                m_copydata(m, sizeof(*eh), sizeof(subtype), &subtype);
                switch (subtype) {
 #if NAGR > 0
@@ -752,6 +756,7 @@
                        }
                        break;
 #endif /* NAGR > 0 */
+
                default:
                        if (subtype == 0 || subtype > 10) {
                                /* illegal value */
@@ -763,6 +768,7 @@
                }
                /* FALLTHROUGH */
        }
+
        default:
                if (m->m_flags & M_PROMISC) {
                        m_freem(m);
@@ -776,7 +782,7 @@
                m->m_flags &= ~M_HASFCS;
        }
 
-       if (etype > ETHERMTU + sizeof (struct ether_header)) {
+       if (etype > ETHERMTU + sizeof(struct ether_header)) {
                /* Strip off the Ethernet header. */
                m_adj(m, ehlen);
 
@@ -799,6 +805,7 @@
                        revarpinput(m); /* XXX queue? */
                        return;
 #endif
+
 #ifdef INET6
                case ETHERTYPE_IPV6:
                        if (__predict_false(!in6_present)) {
@@ -812,22 +819,25 @@
                        pktq = ip6_pktq;
                        break;
 #endif
+
 #ifdef NETATALK
                case ETHERTYPE_ATALK:
                        isr = NETISR_ATALK;
                        inq = &atintrq1;
                        break;
+
                case ETHERTYPE_AARP:
-                       /* probably this should be done with a NETISR as well */
-                       aarpinput(ifp, m); /* XXX */
+                       aarpinput(ifp, m); /* XXX queue? */
                        return;
-#endif /* NETATALK */
+#endif
+
 #ifdef MPLS
                case ETHERTYPE_MPLS:
                        isr = NETISR_MPLS;
                        inq = &mplsintrq;
                        break;
 #endif
+
                default:
                        m_freem(m);
                        return;
@@ -1013,6 +1023,7 @@
        ETHER_UNLOCK(ec);
 
        mutex_obj_free(ec->ec_lock);
+       ec->ec_lock = NULL;
 
        ifp->if_mowner = NULL;
        MOWNER_DETACH(&ec->ec_rx_mowner);