SMP locking for ifnet list.

5 files changed, 58 insertions, 13 deletions

diff --git a/sys/net/bridge.c b/sys/net/bridge.c
index 295c208..13c36cd 100644
--- a/sys/net/bridge.c
+++ b/sys/net/bridge.c
@@ -302,6 +302,7 @@ bridge_off(void)
     int i, s;
 
     DEB(printf("bridge_off: n_clusters %d\n", n_clusters);)
+    IFNET_RLOCK();
     TAILQ_FOREACH(ifp, &ifnet, if_link) {
 	struct bdg_softc *b;
 
@@ -322,6 +323,7 @@ bridge_off(void)
 	b->cluster = NULL;
 	bdg_stats.s[ifp->if_index].name[0] = '\0';
     }
+    IFNET_RUNLOCK();
     /* flush_tables */
 
     s = splimp();
@@ -345,6 +347,7 @@ bridge_on(void)
     struct ifnet *ifp ;
     int s ;
 
+    IFNET_RLOCK();
     TAILQ_FOREACH(ifp, &ifnet, if_link) {
 	struct bdg_softc *b = &ifp2sc[ifp->if_index];
 
@@ -370,6 +373,7 @@ bridge_on(void)
 	    b->flags &= ~IFF_MUTE;
 	}
     }
+    IFNET_RUNLOCK();
 }
 
 /**
@@ -435,6 +439,7 @@ parse_bdg_cfg()
 	/*
 	 * now search in interface list for a matching name
 	 */
+	IFNET_RLOCK();		/* could sleep XXX */
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 	    char buf[IFNAMSIZ];
 
@@ -460,6 +465,7 @@ parse_bdg_cfg()
 		break ;
 	    }
 	}
+	IFNET_RUNLOCK();
 	if (!found)
 	    printf("interface %s Not found in bridge\n", beg);
 	*p = c;
@@ -847,17 +853,10 @@ bdg_forward(struct mbuf *m0, struct ifnet *dst)
 	printf("xx ouch, bdg_forward for local pkt\n");
 	return m0;
     }
-    if (dst == BDG_BCAST || dst == BDG_MCAST || dst == BDG_UNKNOWN) {
-	ifp = TAILQ_FIRST(&ifnet) ; /* scan all ports */
-	once = 0 ;
-	if (dst != BDG_UNKNOWN) /* need a copy for the local stack */
-	    shared = 1 ;
-    } else {
-	ifp = dst ;
-	once = 1 ;
+    if (dst == BDG_BCAST || dst == BDG_MCAST) {
+	 /* need a copy for the local stack */
+	 shared = 1 ;
     }
-    if ((uintptr_t)(ifp) <= (u_int)BDG_FORWARD)
-	panic("bdg_forward: bad dst");
 
     /*
      * Do filtering in a very similar way to what is done in ip_output.
@@ -1023,6 +1022,17 @@ forward:
 	real_dst = src ;
 
     last = NULL;
+    IFNET_RLOCK();
+    if (dst == BDG_BCAST || dst == BDG_MCAST || dst == BDG_UNKNOWN) {
+	ifp = TAILQ_FIRST(&ifnet) ; /* scan all ports */
+	once = 0 ;
+    } else {
+	ifp = dst ;
+	once = 1 ;
+    }
+    if ((uintptr_t)(ifp) <= (u_int)BDG_FORWARD)
+	panic("bdg_forward: bad dst");
+
     for (;;) {
 	if (last) { /* need to forward packet leftover from previous loop */
 	    struct mbuf *m ;
@@ -1032,6 +1042,7 @@ forward:
 	    } else {
 		m = m_copypacket(m0, M_DONTWAIT);
 		if (m == NULL) {
+		    IFNET_RUNLOCK();
 		    printf("bdg_forward: sorry, m_copypacket failed!\n");
 		    bdg_dropped++ ;
 		    return m0 ; /* the original is still there... */
@@ -1062,6 +1073,7 @@ forward:
 	if (ifp == NULL)
 	    once = 1 ;
     }
+    IFNET_RUNLOCK();
     DEB(bdg_fw_ticks += (u_long)(rdtsc() - ticks) ; bdg_fw_count++ ;
 	if (bdg_fw_count != 0) bdg_fw_avg = bdg_fw_ticks/bdg_fw_count; )
     return m0 ;
diff --git a/sys/net/if.c b/sys/net/if.c
index 10c6c10..42f2590 100644
--- a/sys/net/if.c
+++ b/sys/net/if.c
@@ -102,6 +102,7 @@ int	if_index = 0;
 struct	ifindex_entry *ifindex_table = NULL;
 int	ifqmaxlen = IFQ_MAXLEN;
 struct	ifnethead ifnet;	/* depend on static init XXX */
+struct	mtx ifnet_lock;
 int	if_cloners_count;
 LIST_HEAD(, if_clone) if_cloners = LIST_HEAD_INITIALIZER(if_cloners);
 
@@ -263,6 +264,7 @@ if_init(dummy)
 	void *dummy;
 {
 
+	IFNET_LOCK_INIT();
 	TAILQ_INIT(&ifnet);
 	SLIST_INIT(&ifklist);
 	if_grow();				/* create initial table */
@@ -295,6 +297,7 @@ if_check(dummy)
 	int s;
 
 	s = splimp();
+	IFNET_RLOCK();	/* could sleep on rare error; mostly okay XXX */
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 		if (ifp->if_snd.ifq_maxlen == 0) {
 			printf("%s%d XXX: driver didn't set ifq_maxlen\n",
@@ -308,6 +311,7 @@ if_check(dummy)
 			    MTX_NETWORK_LOCK, MTX_DEF);
 		}
 	}
+	IFNET_RUNLOCK();
 	splx(s);
 	if_slowtimo(0);
 }
@@ -376,7 +380,9 @@ if_attach(ifp)
 	register struct sockaddr_dl *sdl;
 	register struct ifaddr *ifa;
 
+	IFNET_WLOCK();
 	TAILQ_INSERT_TAIL(&ifnet, ifp, if_link);
+	IFNET_WUNLOCK();
 	/*
 	 * XXX -
 	 * The old code would work if the interface passed a pre-existing
@@ -537,7 +543,9 @@ if_detach(ifp)
 	mac_destroy_ifnet(ifp);
 #endif /* MAC */
 	KNOTE(&ifp->if_klist, NOTE_EXIT);
+	IFNET_WLOCK();
 	TAILQ_REMOVE(&ifnet, ifp, if_link);
+	IFNET_WUNLOCK();
 	mtx_destroy(&ifp->if_snd.ifq_mtx);
 	splx(s);
 }
@@ -846,6 +854,7 @@ ifa_ifwithaddr(addr)
 	struct ifnet *ifp;
 	struct ifaddr *ifa;
 
+	IFNET_RLOCK();
 	TAILQ_FOREACH(ifp, &ifnet, if_link)
 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 			if (ifa->ifa_addr->sa_family != addr->sa_family)
@@ -861,6 +870,7 @@ ifa_ifwithaddr(addr)
 		}
 	ifa = NULL;
 done:
+	IFNET_RUNLOCK();
 	return (ifa);
 }
 
@@ -875,6 +885,7 @@ ifa_ifwithdstaddr(addr)
 	struct ifnet *ifp;
 	struct ifaddr *ifa;
 
+	IFNET_RLOCK();
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 		if ((ifp->if_flags & IFF_POINTOPOINT) == 0)
 			continue;
@@ -887,6 +898,7 @@ ifa_ifwithdstaddr(addr)
 	}
 	ifa = NULL;
 done:
+	IFNET_RUNLOCK();
 	return (ifa);
 }
 
@@ -918,6 +930,7 @@ ifa_ifwithnet(addr)
 	 * Scan though each interface, looking for ones that have
 	 * addresses in this address family.
 	 */
+	IFNET_RLOCK();
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 		TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
 			register char *cp, *cp2, *cp3;
@@ -980,6 +993,7 @@ next:				continue;
 	}
 	ifa = ifa_maybe;
 done:
+	IFNET_RUNLOCK();
 	return (ifa);
 }
 
@@ -1162,12 +1176,14 @@ if_slowtimo(arg)
 	register struct ifnet *ifp;
 	int s = splimp();
 
+	IFNET_RLOCK();
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 		if (ifp->if_timer == 0 || --ifp->if_timer)
 			continue;
 		if (ifp->if_watchdog)
 			(*ifp->if_watchdog)(ifp);
 	}
+	IFNET_RUNLOCK();
 	splx(s);
 	timeout(if_slowtimo, (void *)0, hz / IFNET_SLOWHZ);
 }
@@ -1192,6 +1208,7 @@ ifunit(const char *name)
 	 * Devices should really be known as /dev/fooN, not /dev/net/fooN.
 	 */
 	snprintf(namebuf, IFNAMSIZ, "%s/%s", net_cdevsw.d_name, name);
+	IFNET_RLOCK();
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 		dev = ifdev_byindex(ifp->if_index);
 		if (strcmp(devtoname(dev), namebuf) == 0)
@@ -1199,6 +1216,7 @@ ifunit(const char *name)
 		if (dev_named(dev, name))
 			break;
 	}
+	IFNET_RUNLOCK();
 	return (ifp);
 }
 
@@ -1625,6 +1643,7 @@ ifconf(cmd, data)
 	int space = ifc->ifc_len, error = 0;
 
 	ifrp = ifc->ifc_req;
+	IFNET_RLOCK();		/* could sleep XXX */
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 		char workbuf[64];
 		int ifnlen, addrs;
@@ -1695,6 +1714,7 @@ ifconf(cmd, data)
 			ifrp++;
 		}
 	}
+	IFNET_RUNLOCK();
 	ifc->ifc_len -= space;
 	return (error);
 }
diff --git a/sys/net/if_ef.c b/sys/net/if_ef.c
index d297faf..b064d38 100644
--- a/sys/net/if_ef.c
+++ b/sys/net/if_ef.c
@@ -163,8 +163,9 @@ ef_detach(struct efnet *sc)
 		    }
 		}
 	}
-
+	IFNET_WLOCK();
 	TAILQ_REMOVE(&ifnet, ifp, if_link);
+	IFNET_WUNLOCK();
 	splx(s);
 	return 0;
 }
@@ -508,6 +509,7 @@ ef_load(void)
 	struct ef_link *efl = NULL;
 	int error = 0, d;
 
+	IFNET_RLOCK();
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 		if (ifp->if_type != IFT_ETHER) continue;
 		EFDEBUG("Found interface %s%d\n", ifp->if_name, ifp->if_unit);
@@ -538,6 +540,7 @@ ef_load(void)
 		efcount++;
 		SLIST_INSERT_HEAD(&efdev, efl, el_next);
 	}
+	IFNET_RUNLOCK();
 	if (error) {
 		if (efl)
 			SLIST_INSERT_HEAD(&efdev, efl, el_next);
diff --git a/sys/net/if_var.h b/sys/net/if_var.h
index 3e3300e..fa4082b 100644
--- a/sys/net/if_var.h
+++ b/sys/net/if_var.h
@@ -410,6 +410,13 @@ struct ifmultiaddr {
 		IFA_UNLOCK(ifa);			\
 	} while (0)
 
+extern	struct mtx ifnet_lock;
+#define	IFNET_LOCK_INIT()	mtx_init(&ifnet_lock, "ifnet", NULL, MTX_DEF)
+#define	IFNET_WLOCK()		mtx_lock(&ifnet_lock)
+#define	IFNET_WUNLOCK()		mtx_unlock(&ifnet_lock)
+#define	IFNET_RLOCK()		IFNET_WLOCK()
+#define	IFNET_RUNLOCK()		IFNET_WUNLOCK()
+
 struct ifindex_entry {
 	struct	ifnet *ife_ifnet;
 	struct	ifaddr *ife_ifnet_addr;
diff --git a/sys/net/rtsock.c b/sys/net/rtsock.c
index d8ec489..40f2ee1 100644
--- a/sys/net/rtsock.c
+++ b/sys/net/rtsock.c
@@ -414,11 +414,12 @@ route_output(m, so)
 			/* new gateway could require new ifaddr, ifp;
 			   flags may also be different; ifp may be specified
 			   by ll sockaddr when protocol address is ambiguous */
-#define	equal(a1, a2) (bcmp((caddr_t)(a1), (caddr_t)(a2), (a1)->sa_len) == 0)
+/* compare two sockaddr structures */
+#define	sa_equal(a1, a2) (bcmp((a1), (a2), (a1)->sa_len) == 0)
 			if ((rt->rt_flags & RTF_GATEWAY && gate != NULL) ||
 			    ifpaddr != NULL ||
 			    (ifaaddr != NULL &&
-			    !equal(ifaaddr, rt->rt_ifa->ifa_addr))) {
+			    !sa_equal(ifaaddr, rt->rt_ifa->ifa_addr))) {
 				if ((error = rt_getifa(&info)) != 0)
 					senderr(error);
 			}
@@ -946,6 +947,7 @@ sysctl_iflist(af, w)
 	int	len, error = 0;
 
 	bzero((caddr_t)&info, sizeof(info));
+	/* IFNET_RLOCK(); */		/* could sleep XXX */
 	TAILQ_FOREACH(ifp, &ifnet, if_link) {
 		if (w->w_arg && w->w_arg != ifp->if_index)
 			continue;
@@ -991,6 +993,7 @@ sysctl_iflist(af, w)
 		ifaaddr = netmask = brdaddr = 0;
 	}
 done:
+	/* IFNET_RUNLOCK(); */ /* XXX */
 	return (error);
 }