ip_tunnel: Add tnl_update_pmtu in ip_md_tunnel_xmit
Add tnl_update_pmtu in ip_md_tunnel_xmit to dynamic modify
the pmtu which packet send through collect_metadata mode
ip tunnel
Signed-off-by: wenxu <wenxu@ucloud.cn>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/ip_tunnel.c b/net/ipv4/ip_tunnel.c
index f98fc4c..6233a7c 100644
--- a/net/ipv4/ip_tunnel.c
+++ b/net/ipv4/ip_tunnel.c
@@ -501,15 +501,19 @@ EXPORT_SYMBOL_GPL(ip_tunnel_encap_setup);
static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
struct rtable *rt, __be16 df,
- const struct iphdr *inner_iph)
+ const struct iphdr *inner_iph,
+ int tunnel_hlen, __be32 dst, bool md)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
- int pkt_size = skb->len - tunnel->hlen - dev->hard_header_len;
+ int pkt_size;
int mtu;
+ tunnel_hlen = md ? tunnel_hlen : tunnel->hlen;
+ pkt_size = skb->len - tunnel_hlen - dev->hard_header_len;
+
if (df)
mtu = dst_mtu(&rt->dst) - dev->hard_header_len
- - sizeof(struct iphdr) - tunnel->hlen;
+ - sizeof(struct iphdr) - tunnel_hlen;
else
mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
@@ -527,11 +531,13 @@ static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
#if IS_ENABLED(CONFIG_IPV6)
else if (skb->protocol == htons(ETH_P_IPV6)) {
struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
+ __be32 daddr;
+
+ daddr = md ? dst : tunnel->parms.iph.daddr;
if (rt6 && mtu < dst_mtu(skb_dst(skb)) &&
mtu >= IPV6_MIN_MTU) {
- if ((tunnel->parms.iph.daddr &&
- !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
+ if ((daddr && !ipv4_is_multicast(daddr)) ||
rt6->rt6i_dst.plen == 128) {
rt6->rt6i_flags |= RTF_MODIFIED;
dst_metric_set(skb_dst(skb), RTAX_MTU, mtu);
@@ -548,7 +554,8 @@ static int tnl_update_pmtu(struct net_device *dev, struct sk_buff *skb,
return 0;
}
-void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto)
+void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
+ u8 proto, int tunnel_hlen)
{
struct ip_tunnel *tunnel = netdev_priv(dev);
u32 headroom = sizeof(struct iphdr);
@@ -598,6 +605,15 @@ void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto)
dev->stats.collisions++;
goto tx_error;
}
+
+ if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
+ df = htons(IP_DF);
+ if (tnl_update_pmtu(dev, skb, rt, df, inner_iph, tunnel_hlen,
+ key->u.ipv4.dst, true)) {
+ ip_rt_put(rt);
+ goto tx_error;
+ }
+
tos = ip_tunnel_ecn_encap(tos, inner_iph, skb);
ttl = key->ttl;
if (ttl == 0) {
@@ -608,10 +624,10 @@ void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev, u8 proto)
else
ttl = ip4_dst_hoplimit(&rt->dst);
}
- if (key->tun_flags & TUNNEL_DONT_FRAGMENT)
- df = htons(IP_DF);
- else if (skb->protocol == htons(ETH_P_IP))
+
+ if (!df && skb->protocol == htons(ETH_P_IP))
df = inner_iph->frag_off & htons(IP_DF);
+
headroom += LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len;
if (headroom > dev->needed_headroom)
dev->needed_headroom = headroom;
@@ -741,7 +757,8 @@ void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
goto tx_error;
}
- if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph)) {
+ if (tnl_update_pmtu(dev, skb, rt, tnl_params->frag_off, inner_iph,
+ 0, 0, false)) {
ip_rt_put(rt);
goto tx_error;
}