diff options
| author | David Wragg <david@weave.works> | 2016-02-10 00:05:57 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-02-10 05:50:03 -0500 |
| commit | 55e5bfb53cff286c1c1ff49f51325dc15c7fea63 (patch) | |
| tree | 37f478a42c7ab91a8dac7047c2c467acb84ce402 | |
| parent | 72564b59ffc438ea103b0727a921aaddce766728 (diff) | |
| download | stm-55e5bfb53cff286c1c1ff49f51325dc15c7fea63.tar.gz | |
geneve: Relax MTU constraints
Allow the MTU of geneve devices to be set to large values, in order to
exploit underlying networks with larger frame sizes.
GENEVE does not have a fixed encapsulation overhead (an openvswitch
rule can add variable length options), so there is no relevant maximum
MTU to enforce. A maximum of IP_MAX_MTU is used instead.
Encapsulated packets that are too big for the underlying network will
get dropped on the floor.
Signed-off-by: David Wragg <david@weave.works>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | drivers/net/geneve.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c index 0b14ac3b8d1189..d2031ce8baea37 100644 --- a/drivers/net/geneve.c +++ b/drivers/net/geneve.c @@ -1039,6 +1039,17 @@ static netdev_tx_t geneve_xmit(struct sk_buff *skb, struct net_device *dev) return geneve_xmit_skb(skb, dev, info); } +static int geneve_change_mtu(struct net_device *dev, int new_mtu) +{ + /* GENEVE overhead is not fixed, so we can't enforce a more + * precise max MTU. + */ + if (new_mtu < 68 || new_mtu > IP_MAX_MTU) + return -EINVAL; + dev->mtu = new_mtu; + return 0; +} + static int geneve_fill_metadata_dst(struct net_device *dev, struct sk_buff *skb) { struct ip_tunnel_info *info = skb_tunnel_info(skb); @@ -1083,7 +1094,7 @@ static const struct net_device_ops geneve_netdev_ops = { .ndo_stop = geneve_stop, .ndo_start_xmit = geneve_xmit, .ndo_get_stats64 = ip_tunnel_get_stats64, - .ndo_change_mtu = eth_change_mtu, + .ndo_change_mtu = geneve_change_mtu, .ndo_validate_addr = eth_validate_addr, .ndo_set_mac_address = eth_mac_addr, .ndo_fill_metadata_dst = geneve_fill_metadata_dst, |