[PATCH net-next 4/5] geneve: use generic function for tunnel IPv6 route lookup

Beniamino Galvani
2023-10-20T11:56:06Z

The route lookup can be done now via generic function
udp_tunnel6_dst_lookup() to replace the custom implementation in
geneve_get_v6_dst().

This is similar to what already done for IPv4 in commit daa2ba7ed1d1
("geneve: use generic function for tunnel IPv4 route lookup").

Suggested-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Beniamino Galvani <b.galvani@gmail.com>
---
drivers/net/geneve.c | 96 ++++++++++++++------------------------------
1 file changed, 31 insertions(+), 65 deletions(-)

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 23041eeec121..acd9c615d1f4 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -800,57 +800,6 @@ static u8 geneve_get_dsfield(struct sk_buff *skb, struct net_device *dev,
return dsfield;
}

-#if IS_ENABLED(CONFIG_IPV6)
-static struct dst_entry *geneve_get_v6_dst(struct sk_buff *skb,
- struct net_device *dev,
- struct geneve_sock *gs6,
- struct flowi6 *fl6,
- const struct ip_tunnel_info *info,
- __be16 dport, __be16 sport)
-{
- bool use_cache = ip_tunnel_dst_cache_usable(skb, info);
- struct geneve_dev *geneve = netdev_priv(dev);
- struct dst_entry *dst = NULL;
- struct dst_cache *dst_cache;
- __u8 prio;
-
- if (!gs6)
- return ERR_PTR(-EIO);
-
- memset(fl6, 0, sizeof(*fl6));
- fl6->flowi6_mark = skb->mark;
- fl6->flowi6_proto = IPPROTO_UDP;
- fl6->daddr = info->key.u.ipv6.dst;
- fl6->saddr = info->key.u.ipv6.src;
- fl6->fl6_dport = dport;
- fl6->fl6_sport = sport;
-
- prio = geneve_get_dsfield(skb, dev, info, &use_cache);
- fl6->flowlabel = ip6_make_flowinfo(prio, info->key.label);
- dst_cache = (struct dst_cache *)&info->dst_cache;
- if (use_cache) {
- dst = dst_cache_get_ip6(dst_cache, &fl6->saddr);
- if (dst)
- return dst;
- }
- dst = ipv6_stub->ipv6_dst_lookup_flow(geneve->net, gs6->sock->sk, fl6,
- NULL);
- if (IS_ERR(dst)) {
- netdev_dbg(dev, "no route to %pI6\n", &fl6->daddr);
- return ERR_PTR(-ENETUNREACH);
- }
- if (dst->dev == dev) { /* is this necessary? */
- netdev_dbg(dev, "circular route to %pI6\n", &fl6->daddr);
- dst_release(dst);
- return ERR_PTR(-ELOOP);
- }
-
- if (use_cache)
- dst_cache_set_ip6(dst_cache, dst, &fl6->saddr);
- return dst;
-}
-#endif
-
static int geneve_xmit_skb(struct sk_buff *skb, struct net_device *dev,
struct geneve_dev *geneve,
const struct ip_tunnel_info *info)
@@ -967,7 +916,8 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
struct geneve_sock *gs6 = rcu_dereference(geneve->sock6);
const struct ip_tunnel_key *key = &info->key;
struct dst_entry *dst = NULL;
- struct flowi6 fl6;
+ struct in6_addr saddr;
+ bool use_cache;
__u8 prio, ttl;
__be16 sport;
int err;
@@ -975,9 +925,18 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
if (!pskb_inet_may_pull(skb))
return -EINVAL;

+ if (!gs6)
+ return -EIO;
+
+ use_cache = ip_tunnel_dst_cache_usable(skb, info);
+ prio = geneve_get_dsfield(skb, dev, info, &use_cache);
sport = udp_flow_src_port(geneve->net, skb, 1, USHRT_MAX, true);
- dst = geneve_get_v6_dst(skb, dev, gs6, &fl6, info,
- geneve->cfg.info.key.tp_dst, sport);
+
+ dst = udp_tunnel6_dst_lookup(skb, dev, geneve->net, gs6->sock, 0,
+ &saddr, key, sport,
+ geneve->cfg.info.key.tp_dst, prio,
+ use_cache ?
+ (struct dst_cache *)&info->dst_cache : NULL);
if (IS_ERR(dst))
return PTR_ERR(dst);

@@ -999,8 +958,8 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
return -ENOMEM;
}

- unclone->key.u.ipv6.dst = fl6.saddr;
- unclone->key.u.ipv6.src = fl6.daddr;
+ unclone->key.u.ipv6.dst = saddr;
+ unclone->key.u.ipv6.src = info->key.u.ipv6.dst;
}

if (!pskb_may_pull(skb, ETH_HLEN)) {
@@ -1014,12 +973,10 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
return -EMSGSIZE;
}

+ prio = ip_tunnel_ecn_encap(prio, ip_hdr(skb), skb);
if (geneve->cfg.collect_md) {
- prio = ip_tunnel_ecn_encap(key->tos, ip_hdr(skb), skb);
ttl = key->ttl;
} else {
- prio = ip_tunnel_ecn_encap(ip6_tclass(fl6.flowlabel),
- ip_hdr(skb), skb);
if (geneve->cfg.ttl_inherit)
ttl = ip_tunnel_get_ttl(ip_hdr(skb), skb);
else
@@ -1032,7 +989,7 @@ static int geneve6_xmit_skb(struct sk_buff *skb, struct net_device *dev,
return err;

udp_tunnel6_xmit_skb(dst, gs6->sock->sk, skb, dev,
- &fl6.saddr, &fl6.daddr, prio, ttl,
+ &saddr, &key->u.ipv6.dst, prio, ttl,
info->key.label, sport, geneve->cfg.info.key.tp_dst,
!(info->key.tun_flags & TUNNEL_CSUM));
return 0;
@@ -1126,19 +1083,28 @@ static int geneve_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb)
#if IS_ENABLED(CONFIG_IPV6)
} else if (ip_tunnel_info_af(info) == AF_INET6) {
struct dst_entry *dst;
- struct flowi6 fl6;
-
struct geneve_sock *gs6 = rcu_dereference(geneve->sock6);
+ struct in6_addr saddr;
+ bool use_cache;
+ u8 prio;
+
+ if (!gs6)
+ return -EIO;
+
+ use_cache = ip_tunnel_dst_cache_usable(skb, info);
+ prio = geneve_get_dsfield(skb, dev, info, &use_cache);
sport = udp_flow_src_port(geneve->net, skb,
1, USHRT_MAX, true);

- dst = geneve_get_v6_dst(skb, dev, gs6, &fl6, info,
- geneve->cfg.info.key.tp_dst, sport);
+ dst = udp_tunnel6_dst_lookup(skb, dev, geneve->net, gs6->sock, 0,
+ &saddr, &info->key, sport,
+ geneve->cfg.info.key.tp_dst, prio,
+ use_cache ? &info->dst_cache : NULL);
if (IS_ERR(dst))
return PTR_ERR(dst);

dst_release(dst);
- info->key.u.ipv6.src = fl6.saddr;
+ info->key.u.ipv6.src = saddr;
#endif
} else {
return -EINVAL;
--
2.40.1