Index: if_tun.c
===================================================================
RCS file: /cvs/src/sys/net/if_tun.c,v
retrieving revision 1.199
diff -u -p -r1.199 if_tun.c
--- if_tun.c	23 Jan 2020 03:10:18 -0000	1.199
+++ if_tun.c	23 Jan 2020 03:57:57 -0000
@@ -56,7 +56,7 @@
 #include <sys/signalvar.h>
 #include <sys/poll.h>
 #include <sys/conf.h>
-
+#include <sys/percpu.h>
 
 #include <net/if.h>
 #include <net/if_types.h>
@@ -245,6 +245,8 @@ tun_create(struct if_clone *ifc, int uni
 	ifp->if_link_state = LINK_STATE_DOWN;
 	IFQ_SET_MAXLEN(&ifp->if_snd, IFQ_MAXLEN);
 
+	if_counters_alloc(ifp);
+
 	if ((flags & TUN_LAYER2) == 0) {
 		if (tun_list_insert(&tun_softc_list, sc) != 0)
 			goto exists;
@@ -843,10 +845,10 @@ int
 tun_dev_write(struct tun_softc *sc, struct uio *uio, int ioflag)
 {
 	struct ifnet		*ifp;
-	u_int32_t		*th;
-	struct mbuf		*top, **mp, *m;
-	int			error = 0, tlen;
-	size_t			mlen;
+	struct mbuf		*m;
+	int			error = 0;
+	int			mlen;
+	int			align;
 
 	ifp = &sc->sc_if;
 	TUNDEBUG(("%s: tunwrite\n", ifp->if_xname));
@@ -856,112 +858,82 @@ tun_dev_write(struct tun_softc *sc, stru
 		TUNDEBUG(("%s: len=%d!\n", ifp->if_xname, uio->uio_resid));
 		return (EMSGSIZE);
 	}
-	tlen = uio->uio_resid;
 
-	/* get a header mbuf */
-	MGETHDR(m, M_DONTWAIT, MT_DATA);
+	align = max_linkhdr;
+	if (sc->sc_flags & TUN_LAYER2)
+		align += ETHER_ALIGN;
+
+	mlen = uio->uio_resid + align;
+
+	m = m_gethdr(M_DONTWAIT, MT_DATA);
 	if (m == NULL)
-		return (ENOBUFS);
-	mlen = MHLEN;
-	if (uio->uio_resid >= MINCLSIZE) {
-		MCLGET(m, M_DONTWAIT);
-		if (!(m->m_flags & M_EXT)) {
-			m_free(m);
-			return (ENOBUFS);
+		return (ENOMEM);
+	if (mlen > MHLEN) {
+                m_clget(m, M_WAITOK, mlen);
+		if (!ISSET(m->m_flags, M_EXT)) {
+			error = ENOMEM;
+			goto drop;
 		}
-		mlen = MCLBYTES;
 	}
 
-	top = NULL;
-	mp = &top;
-	if (sc->sc_flags & TUN_LAYER2) {
-		/*
-		 * Pad so that IP header is correctly aligned
-		 * this is necessary for all strict aligned architectures.
-		 */
-		mlen -= ETHER_ALIGN;
-		m->m_data += ETHER_ALIGN;
-	}
-	while (error == 0 && uio->uio_resid > 0) {
-		m->m_len = ulmin(mlen, uio->uio_resid);
-		error = uiomove(mtod (m, caddr_t), m->m_len, uio);
-		*mp = m;
-		mp = &m->m_next;
-		if (error == 0 && uio->uio_resid > 0) {
-			MGET(m, M_DONTWAIT, MT_DATA);
-			if (m == NULL) {
-				error = ENOBUFS;
-				break;
-			}
-			mlen = MLEN;
-			if (uio->uio_resid >= MINCLSIZE) {
-				MCLGET(m, M_DONTWAIT);
-				if (!(m->m_flags & M_EXT)) {
-					error = ENOBUFS;
-					m_free(m);
-					break;
-				}
-				mlen = MCLBYTES;
-			}
-		}
-	}
-	if (error) {
-		m_freem(top);
-		ifp->if_ierrors++;
-		return (error);
-	}
+	m_align(m, mlen);
+	m->m_pkthdr.len = m->m_len = mlen;
+	m_adj(m, align);
+
+	error = uiomove(mtod(m, void *), m->m_len, uio);
+	if (error != 0)
+		goto drop;
 
-	top->m_pkthdr.len = tlen;
+	NET_RLOCK();
 
-	if (sc->sc_flags & TUN_LAYER2) {
-		struct mbuf_list ml = MBUF_LIST_INITIALIZER();
+	if (sc->sc_flags & TUN_LAYER2)
+		if_vinput(ifp, m);
+	else {
+		uint32_t af;
 
-		ml_enqueue(&ml, top);
-		if_input(ifp, &ml);
-		return (0);
-	}
+		m->m_pkthdr.ph_ifidx = ifp->if_index;
+		m->m_pkthdr.ph_rtableid = ifp->if_rdomain;
 
 #if NBPFILTER > 0
-	if (ifp->if_bpf) {
-		bpf_mtap(ifp->if_bpf, top, BPF_DIRECTION_IN);
-	}
+		if (ifp->if_bpf) {
+			bpf_mtap(ifp->if_bpf, m, BPF_DIRECTION_IN);
+			/* XXX BPF can ask to drop */
+		}
 #endif
 
-	th = mtod(top, u_int32_t *);
-	/* strip the tunnel header */
-	top->m_data += sizeof(*th);
-	top->m_len  -= sizeof(*th);
-	top->m_pkthdr.len -= sizeof(*th);
-	top->m_pkthdr.ph_rtableid = ifp->if_rdomain;
-	top->m_pkthdr.ph_ifidx = ifp->if_index;
-
-	ifp->if_ipackets++;
-	ifp->if_ibytes += top->m_pkthdr.len;
-
-	NET_LOCK();
-
-	switch (ntohl(*th)) {
-	case AF_INET:
-		ipv4_input(ifp, top);
-		break;
+		af = *mtod(m, uint32_t *);
+		m_adj(m, sizeof(af));
+
+		counters_pkt(ifp->if_counters,
+		    ifc_ipackets, ifc_ibytes, m->m_pkthdr.len);
+
+		switch (af) {
+		case AF_INET:
+			ipv4_input(ifp, m);
+			break;
 #ifdef INET6
-	case AF_INET6:
-		ipv6_input(ifp, top);
-		break;
+		case AF_INET6:
+			ipv6_input(ifp, m);
+			break;
 #endif
 #ifdef MPLS
-	case AF_MPLS:
-		mpls_input(ifp, top);
-		break;
+		case AF_MPLS:
+			mpls_input(ifp, m);
+			break;
 #endif
-	default:
-		m_freem(top);
-		error = EAFNOSUPPORT;
-		break;
+		default:
+			m_freem(m);
+			error = EAFNOSUPPORT;
+			break;
+		}
 	}
 
-	NET_UNLOCK();
+	NET_RUNLOCK();
+
+	return (error);
 
+drop:
+	m_freem(m);
 	return (error);
 }