add utility routine for updating an struct llentry *

2 files changed, 35 insertions, 0 deletions

diff --git a/sys/net/if_llatbl.c b/sys/net/if_llatbl.c
index 2287f92c7e95..d7fb37a2b040 100644
--- a/sys/net/if_llatbl.c
+++ b/sys/net/if_llatbl.c
@@ -103,6 +103,39 @@ llentry_free(struct llentry *lle)
 	LLE_FREE_LOCKED(lle);
 }
 
+int
+llentry_update(struct llentry **llep, struct lltable *lt,
+    struct sockaddr *dst, struct ifnet *ifp)
+{
+	struct llentry *la;
+
+	IF_AFDATA_RLOCK(ifp);	
+	la = lla_lookup(lt, LLE_EXCLUSIVE,
+	    (struct sockaddr *)dst);
+	IF_AFDATA_RUNLOCK(ifp);
+	if ((la == NULL) && 
+	    (ifp->if_flags & (IFF_NOARP | IFF_STATICARP)) == 0) {
+		IF_AFDATA_WLOCK(ifp);
+		la = lla_lookup(lt,
+		    (LLE_CREATE | LLE_EXCLUSIVE),
+		    (struct sockaddr *)dst);
+		IF_AFDATA_WUNLOCK(ifp);	
+	}
+	if (la != NULL && (*llep != la)) {
+		if (*llep != NULL)
+			LLE_FREE(*llep);
+		LLE_ADDREF(la);
+		LLE_WUNLOCK(la);
+		*llep = la;
+	} else if (la != NULL)
+		LLE_WUNLOCK(la);
+
+	if (la == NULL)
+		return (ENOENT);
+
+	return (0);
+}
+
 /*
  * Free all entries from given table and free itself.
  * Since lltables collects from all of the intefaces,
diff --git a/sys/net/if_llatbl.h b/sys/net/if_llatbl.h
index 50e617d9d679..3b3086f75f76 100644
--- a/sys/net/if_llatbl.h
+++ b/sys/net/if_llatbl.h
@@ -178,6 +178,8 @@ void		lltable_drain(int);
 int		lltable_sysctl_dumparp(int, struct sysctl_req *);
 
 void		llentry_free(struct llentry *);
+int		llentry_update(struct llentry **, struct lltable *,
+                       struct sockaddr *, struct ifnet *);
 
 /*
  * Generic link layer address lookup function.