Allow different bridge types to coexist

if_bridge has a lot of limitations that make it scale poorly to higher data
rates. In my projects/VPC branch I leverage the bridge interface between
layers for my high speed soft switch as well as for purposes of stacking
in general.

Reviewed by:	sbruno@
Approved by:	sbruno@
Differential Revision:	https://reviews.freebsd.org/D15344

sys/net/if.c

@@ -221,7 +221,6 @@ static MALLOC_DEFINE(M_IFDESCR, "ifdescr", "ifnet descriptions");
 static struct sx ifdescr_sx;
 SX_SYSINIT(ifdescr_sx, &ifdescr_sx, "ifnet descr");
 
-void	(*bridge_linkstate_p)(struct ifnet *ifp);
 void	(*ng_ether_link_state_p)(struct ifnet *ifp, int state);
 void	(*lagg_linkstate_p)(struct ifnet *ifp, int state);
 /* These are external hooks for CARP. */
@@ -2318,7 +2317,7 @@ do_link_state_change(void *arg, int pending)
 	if (ifp->if_carp)
 		(*carp_linkstate_p)(ifp);
 	if (ifp->if_bridge)
-		(*bridge_linkstate_p)(ifp);
+		ifp->if_bridge_linkstate(ifp);
 	if (ifp->if_lagg)
 		(*lagg_linkstate_p)(ifp, link_state);
 

sys/net/if_bridge.c

@@ -340,7 +340,6 @@ static int	bridge_fragment(struct ifnet *, struct mbuf **mp,
 static void	bridge_linkstate(struct ifnet *ifp);
 static void	bridge_linkcheck(struct bridge_softc *sc);
 
-extern void (*bridge_linkstate_p)(struct ifnet *ifp);
 
 /* The default bridge vlan is 1 (IEEE 802.1Q-2003 Table 9-2) */
 #define	VLANTAGOF(_m)	\
@@ -556,10 +555,7 @@ bridge_modevent(module_t mod, int type, void *data)
 		bridge_rtnode_zone = uma_zcreate("bridge_rtnode",
 		    sizeof(struct bridge_rtnode), NULL, NULL, NULL, NULL,
 		    UMA_ALIGN_PTR, 0);
-		bridge_input_p = bridge_input;
-		bridge_output_p = bridge_output;
 		bridge_dn_p = bridge_dummynet;
-		bridge_linkstate_p = bridge_linkstate;
 		bridge_detach_cookie = EVENTHANDLER_REGISTER(
 		    ifnet_departure_event, bridge_ifdetach, NULL,
 		    EVENTHANDLER_PRI_ANY);
@@ -568,10 +564,7 @@ bridge_modevent(module_t mod, int type, void *data)
 		EVENTHANDLER_DEREGISTER(ifnet_departure_event,
 		    bridge_detach_cookie);
 		uma_zdestroy(bridge_rtnode_zone);
-		bridge_input_p = NULL;
-		bridge_output_p = NULL;
 		bridge_dn_p = NULL;
-		bridge_linkstate_p = NULL;
 		break;
 	default:
 		return (EOPNOTSUPP);
@@ -1041,6 +1034,9 @@ bridge_delete_member(struct bridge_softc *sc, struct bridge_iflist *bif,
 	KASSERT(bif->bif_addrcnt == 0,
 	    ("%s: %d bridge routes referenced", __func__, bif->bif_addrcnt));
 
+	ifs->if_bridge_output = NULL;
+	ifs->if_bridge_input = NULL;
+	ifs->if_bridge_linkstate = NULL;
 	BRIDGE_UNLOCK(sc);
 	if (!gone) {
 		switch (ifs->if_type) {
@@ -1198,6 +1194,9 @@ bridge_ioctl_add(struct bridge_softc *sc, void *arg)
 	}
 
 	ifs->if_bridge = sc;
+	ifs->if_bridge_output = bridge_output;
+	ifs->if_bridge_input = bridge_input;
+	ifs->if_bridge_linkstate = bridge_linkstate;
 	bstp_create(&sc->sc_stp, &bif->bif_stp, bif->bif_ifp);
 	/*
 	 * XXX: XLOCK HERE!?!

sys/net/if_bridgevar.h

@@ -310,22 +310,19 @@ struct ifbpstpconf {
 } while (0)
 
 #define BRIDGE_INPUT(_ifp, _m)		do {			\
-	KASSERT(bridge_input_p != NULL,			\
+		KASSERT((_ifp)->if_bridge_input != NULL,		\
 	    ("%s: if_bridge not loaded!", __func__));	\
-	_m = (*bridge_input_p)(_ifp, _m);		\
+	_m = (*(_ifp)->if_bridge_input)(_ifp, _m);			\
 	if (_m != NULL)					\
 		_ifp = _m->m_pkthdr.rcvif;		\
 } while (0)
 
 #define BRIDGE_OUTPUT(_ifp, _m, _err)	do {    		\
-	KASSERT(bridge_output_p != NULL,			\
+	KASSERT((_ifp)->if_bridge_output != NULL,		\
 	    ("%s: if_bridge not loaded!", __func__));		\
-	_err = (*bridge_output_p)(_ifp, _m, NULL, NULL);	\
+	_err = (*(_ifp)->if_bridge_output)(_ifp, _m, NULL, NULL);	\
 } while (0)
 
-extern	struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *);
-extern	int (*bridge_output_p)(struct ifnet *, struct mbuf *,
-		struct sockaddr *, struct rtentry *);
 extern	void (*bridge_dn_p)(struct mbuf *, struct ifnet *);
 
 #endif /* _KERNEL */

sys/net/if_ethersubr.c

@@ -102,9 +102,6 @@ void	(*ng_ether_detach_p)(struct ifnet *ifp);
 void	(*vlan_input_p)(struct ifnet *, struct mbuf *);
 
 /* if_bridge(4) support */
-struct mbuf *(*bridge_input_p)(struct ifnet *, struct mbuf *); 
-int	(*bridge_output_p)(struct ifnet *, struct mbuf *, 
-		struct sockaddr *, struct rtentry *);
 void	(*bridge_dn_p)(struct mbuf *, struct ifnet *);
 
 /* if_lagg(4) support */

sys/net/if_var.h

@@ -321,6 +321,10 @@ struct ifnet {
 		     struct route *);
 	void	(*if_input)		/* input routine (from h/w driver) */
 		(struct ifnet *, struct mbuf *);
+	struct mbuf *(*if_bridge_input)(struct ifnet *, struct mbuf *);
+	int	(*if_bridge_output)(struct ifnet *, struct mbuf *, struct sockaddr *,
+		    struct rtentry *);
+	void (*if_bridge_linkstate)(struct ifnet *ifp);
 	if_start_fn_t	if_start;	/* initiate output routine */
 	if_ioctl_fn_t	if_ioctl;	/* ioctl routine */
 	if_init_fn_t	if_init;	/* Init routine */