Commit c46b7897 authored by pravin shelar's avatar pravin shelar Committed by David S. Miller
Browse files

vxlan: simplify exception handling 



vxlan egress path error handling has became complicated, it
need to handle IPv4 and IPv6 tunnel cases.
Earlier patch removes vlan handling from vxlan_build_skb(), so
vxlan_build_skb does not need to free skb and we can simplify
the xmit path by having single error handling for both type of
tunnels.

Signed-off-by: default avatarPravin B Shelar <pshelar@ovn.org>
Acked-by: default avatarJiri Benc <jbenc@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 03dc52a8

drivers/net/vxlan.c

+19 −27
Original line number Diff line number Diff line
@@ -1755,11 +1755,11 @@ static int vxlan_build_skb(struct sk_buff *skb, struct dst_entry *dst, 
	/* Need space for new headers (invalidates iph ptr) */

	err = skb_cow_head(skb, min_headroom);

	if (unlikely(err))

		goto out_free;

		return err;



	err = iptunnel_handle_offloads(skb, type);

	if (err)

		goto out_free;

		return err;



	vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh));

	vxh->vx_flags = VXLAN_HF_VNI;
@@ -1783,16 +1783,12 @@ static int vxlan_build_skb(struct sk_buff *skb, struct dst_entry *dst, 
	if (vxflags & VXLAN_F_GPE) {

		err = vxlan_build_gpe_hdr(vxh, vxflags, skb->protocol);

		if (err < 0)

			goto out_free;

			return err;

		inner_protocol = skb->protocol;

	}



	skb_set_inner_protocol(skb, inner_protocol);

	return 0;



out_free:

	kfree_skb(skb);

	return err;

}



static struct rtable *vxlan_get_route(struct vxlan_dev *vxlan,
@@ -1929,13 +1925,13 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 
	struct ip_tunnel_info *info;

	struct vxlan_dev *vxlan = netdev_priv(dev);

	struct sock *sk;

	struct rtable *rt = NULL;

	const struct iphdr *old_iph;

	union vxlan_addr *dst;

	union vxlan_addr remote_ip, local_ip;

	union vxlan_addr *src;

	struct vxlan_metadata _md;

	struct vxlan_metadata *md = &_md;

	struct dst_entry *ndst = NULL;

	__be16 src_port = 0, dst_port;

	__be32 vni, label;

	__be16 df = 0;
@@ -2011,6 +2007,7 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 


	if (dst->sa.sa_family == AF_INET) {

		struct vxlan_sock *sock4 = rcu_dereference(vxlan->vn4_sock);

		struct rtable *rt;



		if (!sock4)

			goto drop;
@@ -2032,7 +2029,8 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 
			netdev_dbg(dev, "circular route to %pI4\n",

				   &dst->sin.sin_addr.s_addr);

			dev->stats.collisions++;

			goto rt_tx_error;

			ip_rt_put(rt);

			goto tx_error;

		}



		/* Bypass encapsulation if the destination is local */
@@ -2055,12 +2053,13 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 
		else if (info->key.tun_flags & TUNNEL_DONT_FRAGMENT)

			df = htons(IP_DF);



		ndst = &rt->dst;

		tos = ip_tunnel_ecn_encap(tos, old_iph, skb);

		ttl = ttl ? : ip4_dst_hoplimit(&rt->dst);

		err = vxlan_build_skb(skb, &rt->dst, sizeof(struct iphdr),

		err = vxlan_build_skb(skb, ndst, sizeof(struct iphdr),

				      vni, md, flags, udp_sum);

		if (err < 0)

			goto xmit_tx_error;

			goto tx_error;



		udp_tunnel_xmit_skb(rt, sk, skb, src->sin.sin_addr.s_addr,

				    dst->sin.sin_addr.s_addr, tos, ttl, df,
@@ -2068,7 +2067,6 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 
#if IS_ENABLED(CONFIG_IPV6)

	} else {

		struct vxlan_sock *sock6 = rcu_dereference(vxlan->vn6_sock);

		struct dst_entry *ndst;

		u32 rt6i_flags;



		ndst = vxlan6_get_route(vxlan, sock6, skb,
@@ -2080,13 +2078,13 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 
			netdev_dbg(dev, "no route to %pI6\n",

				   &dst->sin6.sin6_addr);

			dev->stats.tx_carrier_errors++;

			ndst = NULL;

			goto tx_error;

		}



		if (ndst->dev == dev) {

			netdev_dbg(dev, "circular route to %pI6\n",

				   &dst->sin6.sin6_addr);

			dst_release(ndst);

			dev->stats.collisions++;

			goto tx_error;

		}
@@ -2098,12 +2096,12 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 
		    !(rt6i_flags & (RTCF_BROADCAST | RTCF_MULTICAST))) {

			struct vxlan_dev *dst_vxlan;



			dst_release(ndst);

			dst_vxlan = vxlan_find_vni(vxlan->net, vni,

						   dst->sa.sa_family, dst_port,

						   vxlan->flags);

			if (!dst_vxlan)

				goto tx_error;

			dst_release(ndst);

			vxlan_encap_bypass(skb, vxlan, dst_vxlan);

			return;

		}
@@ -2116,11 +2114,9 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 
		skb_scrub_packet(skb, xnet);

		err = vxlan_build_skb(skb, ndst, sizeof(struct ipv6hdr),

				      vni, md, flags, udp_sum);

		if (err < 0) {

			dst_release(ndst);

			dev->stats.tx_errors++;

			return;

		}

		if (err < 0)

			goto tx_error;



		udp_tunnel6_xmit_skb(ndst, sk, skb, dev,

				     &src->sin6.sin6_addr,

				     &dst->sin6.sin6_addr, tos, ttl,
@@ -2132,17 +2128,13 @@ static void vxlan_xmit_one(struct sk_buff *skb, struct net_device *dev, 


drop:

	dev->stats.tx_dropped++;

	goto tx_free;

	dev_kfree_skb(skb);

	return;



xmit_tx_error:

	/* skb is already freed. */

	skb = NULL;

rt_tx_error:

	ip_rt_put(rt);

tx_error:

	dst_release(ndst);

	dev->stats.tx_errors++;

tx_free:

	dev_kfree_skb(skb);

	kfree_skb(skb);

}



/* Transmit local packets over Vxlan

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