Module Name: src
Committed By: roy
Date: Tue Oct 13 09:33:35 UTC 2015
Modified Files:
src/sys/netinet: if_arp.c
Log Message:
Simplify la handling in arpresolve() by asking arplookup() not to create
a la. If a la is needed arpresolve() will then create it or mark the
current la as writable.
To generate a diff of this commit:
cvs rdiff -u -r1.184 -r1.185 src/sys/netinet/if_arp.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/netinet/if_arp.c
diff -u src/sys/netinet/if_arp.c:1.184 src/sys/netinet/if_arp.c:1.185
--- src/sys/netinet/if_arp.c:1.184 Thu Oct 8 08:17:37 2015
+++ src/sys/netinet/if_arp.c Tue Oct 13 09:33:35 2015
@@ -1,4 +1,4 @@
-/* $NetBSD: if_arp.c,v 1.184 2015/10/08 08:17:37 roy Exp $ */
+/* $NetBSD: if_arp.c,v 1.185 2015/10/13 09:33:35 roy Exp $ */
/*-
* Copyright (c) 1998, 2000, 2008 The NetBSD Foundation, Inc.
@@ -68,7 +68,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.184 2015/10/08 08:17:37 roy Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_arp.c,v 1.185 2015/10/13 09:33:35 roy Exp $");
#ifdef _KERNEL_OPT
#include "opt_ddb.h"
@@ -791,26 +791,17 @@ arpresolve(struct ifnet *ifp, struct rte
{
struct llentry *la;
const struct sockaddr_dl *sdl;
- int renew;
- int flags = 0;
+ const char *create_lookup;
+ bool renew;
int error;
KASSERT(m != NULL);
- la = arplookup(ifp, m, &satocsin(dst)->sin_addr, 1, 0, 0, rt);
- if (la != NULL)
- rt = la->la_rt;
+ la = arplookup(ifp, m, &satocsin(dst)->sin_addr, 0, 0, 0, rt);
+ if (la == NULL || la->la_rt == NULL)
+ goto notfound;
- if (la == NULL || rt == NULL) {
- ARP_STATINC(ARP_STAT_ALLOCFAIL);
- log(LOG_DEBUG,
- "arpresolve: can't allocate llinfo on %s for %s\n",
- ifp->if_xname, in_fmtaddr(satocsin(dst)->sin_addr));
- m_freem(m);
- if (la != NULL)
- LLE_RUNLOCK(la);
- return 0;
- }
+ rt = la->la_rt;
sdl = satocsdl(rt->rt_gateway);
/*
* Check the address family and length is valid, the address
@@ -837,69 +828,82 @@ arpresolve(struct ifnet *ifp, struct rte
}
#endif
-retry:
+notfound:
if (la == NULL) {
- IF_AFDATA_RLOCK(ifp);
- la = lla_lookup(LLTABLE(ifp), flags, dst);
- IF_AFDATA_RUNLOCK(ifp);
- }
-
#ifdef IFF_STATICARP /* FreeBSD */
#define _IFF_NOARP (IFF_NOARP | IFF_STATICARP)
#else
#define _IFF_NOARP IFF_NOARP
#endif
- if ((la == NULL) && ((flags & LLE_EXCLUSIVE) == 0)
- && ((ifp->if_flags & _IFF_NOARP) == 0))
- {
- flags |= LLE_EXCLUSIVE;
+ if (ifp->if_flags & _IFF_NOARP) {
+ m_freem(m);
+ return 0;
+ }
+#undef _IFF_NOARP
+ create_lookup = "create";
IF_AFDATA_WLOCK(ifp);
- la = lla_create(LLTABLE(ifp), flags, dst);
+ la = lla_create(LLTABLE(ifp), LLE_EXCLUSIVE, dst);
IF_AFDATA_WUNLOCK(ifp);
-
- if (la == NULL) {
- log(LOG_DEBUG,
- "%s: failed to create llentry for %s on %s\n",
- __func__, inet_ntoa(satocsin(dst)->sin_addr),
- ifp->if_xname);
- }
+ if (la == NULL)
+ ARP_STATINC(ARP_STAT_ALLOCFAIL);
+ } else if (LLE_TRY_UPGRADE(la) == 0) {
+ create_lookup = "lookup";
+ LLE_RUNLOCK(la);
+ IF_AFDATA_RLOCK(ifp);
+ la = lla_lookup(LLTABLE(ifp), LLE_EXCLUSIVE, dst);
+ IF_AFDATA_RUNLOCK(ifp);
}
-#undef _IFF_NOARP
if (la == NULL) {
+ log(LOG_DEBUG,
+ "%s: failed to %s llentry for %s on %s\n",
+ __func__, create_lookup, inet_ntoa(satocsin(dst)->sin_addr),
+ ifp->if_xname);
m_freem(m);
return 0;
}
+ /* Just in case */
+ if (la->la_rt == NULL) {
+ log(LOG_DEBUG,
+ "%s: valid llentry has no rtentry for %s on %s\n",
+ __func__, inet_ntoa(satocsin(dst)->sin_addr),
+ ifp->if_xname);
+ m_freem(m);
+ return 0;
+ }
+ rt = la->la_rt;
+
if ((la->la_flags & LLE_VALID) &&
- ((la->la_flags & LLE_STATIC) || la->la_expire > time_uptime)) {
+ ((la->la_flags & LLE_STATIC) || la->la_expire > time_uptime))
+ {
+ sdl = satocsdl(rt->rt_gateway);
memcpy(desten, CLLADDR(sdl),
min(sdl->sdl_alen, ifp->if_addrlen));
- renew = 0;
+ renew = false;
/*
* If entry has an expiry time and it is approaching,
* see if we need to send an ARP request within this
* arpt_down interval.
*/
if (!(la->la_flags & LLE_STATIC) &&
- time_uptime + la->la_preempt > la->la_expire) {
- renew = 1;
+ time_uptime + la->la_preempt > la->la_expire)
+ {
+ renew = true;
la->la_preempt--;
}
- if (flags & LLE_EXCLUSIVE)
- LLE_WUNLOCK(la);
- else
- LLE_RUNLOCK(la);
+ LLE_WUNLOCK(la);
- if (renew == 1) {
+ if (renew) {
const u_int8_t *enaddr =
#if NCARP > 0
(rt->rt_ifp->if_type == IFT_CARP) ?
CLLADDR(rt->rt_ifp->if_sadl):
#endif
CLLADDR(ifp->if_sadl);
- arprequest(ifp, &satocsin(rt->rt_ifa->ifa_addr)->sin_addr,
+ arprequest(ifp,
+ &satocsin(rt->rt_ifa->ifa_addr)->sin_addr,
&satocsin(dst)->sin_addr, enaddr);
}
@@ -915,12 +919,6 @@ retry:
}
renew = (la->la_asked == 0 || la->la_expire != time_uptime);
- if (renew && (flags & LLE_EXCLUSIVE) == 0) {
- flags |= LLE_EXCLUSIVE;
- LLE_RUNLOCK(la);
- la = NULL;
- goto retry;
- }
/*
* There is an arptab entry, but no ethernet address
@@ -946,10 +944,8 @@ retry:
} else
la->la_hold = m;
la->la_numheld++;
- if (renew == 0 && (flags & LLE_EXCLUSIVE)) {
- flags &= ~LLE_EXCLUSIVE;
+ if (!renew)
LLE_DOWNGRADE(la);
- }
/*
* Return EWOULDBLOCK if we have tried less than arp_maxtries. It
@@ -975,19 +971,15 @@ retry:
callout_reset(&la->la_timer, hz * arpt_down,
arptimer, la);
la->la_asked++;
- if (flags & LLE_EXCLUSIVE)
- LLE_WUNLOCK(la);
- else
- LLE_RUNLOCK(la);
+ LLE_WUNLOCK(la);
+
arprequest(ifp, &satocsin(rt->rt_ifa->ifa_addr)->sin_addr,
&satocsin(dst)->sin_addr, enaddr);
return error == 0;
}
done:
- if (flags & LLE_EXCLUSIVE)
- LLE_WUNLOCK(la);
- else
- LLE_RUNLOCK(la);
+ LLE_RUNLOCK(la);
+
return error == 0;
}
