Le 20 nov. 2018 à 15:57, David Ahern <d...@cumulusnetworks.com> a écrit :
>
> On 11/20/18 7:23 AM, Alexis Bauvin wrote:
>> Creating a VXLAN device with is underlay in the non-default VRF makes
>> egress route lookup fail or incorrect since it will resolve in the
>> default VRF, and ingress fail because the socket listens in the default
>> VRF.
>>
>> This patch binds the underlying UDP tunnel socket to the l3mdev of the
>> lower device of the VXLAN device. This will listen in the proper VRF and
>> output traffic from said l3mdev, matching l3mdev routing rules and
>> looking up the correct routing table.
>>
>> When the VXLAN device does not have a lower device, or the lower device
>> is in the default VRF, the socket will not be bound to any interface,
>> keeping the previous behaviour.
>>
>> The underlay l3mdev is deduced from the VXLAN lower device
>> (IFLA_VXLAN_LINK).
>>
>> The l3mdev_master_upper_ifindex_by_index function has been added to
>> l3mdev. Its goal is to fetch the effective l3mdev of an interface which
>> is not a direct slave of said l3mdev. It handles the following example,
>> properly resolving the l3mdev of eth0 to vrf-blue:
>>
>> +----------+ +---------+
>> | | | |
>> | vrf-blue | | vrf-red |
>> | | | |
>> +----+-----+ +----+----+
>> | |
>> | |
>> +----+-----+ +----+----+
>> | | | |
>> | br-blue | | br-red |
>> | | | |
>> +----+-----+ +---+-+---+
>> | | |
>> | +-----+ +-----+
>> | | |
>> +----+-----+ +------+----+ +----+----+
>> | | lower device | | | |
>> | eth0 | <- - - - - - - | vxlan-red | | tap-red | (... more taps)
>> | | | | | |
>> +----------+ +-----------+ +---------+
>
> same here. Very helpful diagram.
>
>
>> diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
>> index 27bd586b94b0..a3de08122269 100644
>> --- a/drivers/net/vxlan.c
>> +++ b/drivers/net/vxlan.c
>
> The vxlan changes look ok to me. It would be good for someone who know
> that code better than I do to review it.
>
> Move the following l3mdev changes to a separate patch - introduce infra
> changes separate from their use:
Sure, will do in next version. Thanks!
>> diff --git a/include/net/l3mdev.h b/include/net/l3mdev.h
>> index 3832099289c5..78fa0ac4613c 100644
>> --- a/include/net/l3mdev.h
>> +++ b/include/net/l3mdev.h
>> @@ -101,6 +101,17 @@ struct net_device *l3mdev_master_dev_rcu(const struct
>> net_device *_dev)
>> return master;
>> }
>>
>> +int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex);
>> +static inline
>> +int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
>> +{
>> + rcu_read_lock();
>> + ifindex = l3mdev_master_upper_ifindex_by_index_rcu(net, ifindex);
>> + rcu_read_unlock();
>> +
>> + return ifindex;
>> +}
>> +
>> u32 l3mdev_fib_table_rcu(const struct net_device *dev);
>> u32 l3mdev_fib_table_by_index(struct net *net, int ifindex);
>> static inline u32 l3mdev_fib_table(const struct net_device *dev)
>> @@ -207,6 +218,17 @@ static inline int l3mdev_master_ifindex_by_index(struct
>> net *net, int ifindex)
>> return 0;
>> }
>>
>> +static inline
>> +int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
>> +{
>> + return 0;
>> +}
>> +static inline
>> +int l3mdev_master_upper_ifindex_by_index(struct net *net, int ifindex)
>> +{
>> + return 0;
>> +}
>> +
>> static inline
>> struct net_device *l3mdev_master_dev_rcu(const struct net_device *dev)
>> {
>> diff --git a/net/l3mdev/l3mdev.c b/net/l3mdev/l3mdev.c
>> index 8da86ceca33d..309dee76724e 100644
>> --- a/net/l3mdev/l3mdev.c
>> +++ b/net/l3mdev/l3mdev.c
>> @@ -46,6 +46,24 @@ int l3mdev_master_ifindex_rcu(const struct net_device
>> *dev)
>> }
>> EXPORT_SYMBOL_GPL(l3mdev_master_ifindex_rcu);
>>
>> +/**
>> + * l3mdev_master_upper_ifindex_by_index - get index of upper l3 master
>> + * device
>> + * @net: network namespace for device index lookup
>> + * @ifindex: targeted interface
>> + */
>> +int l3mdev_master_upper_ifindex_by_index_rcu(struct net *net, int ifindex)
>> +{
>> + struct net_device *dev;
>> +
>> + dev = dev_get_by_index_rcu(net, ifindex);
>> + while (dev && !netif_is_l3_master(dev))
>> + dev = netdev_master_upper_dev_get(dev);
>> +
>> + return dev ? dev->ifindex : 0;
>> +}
>> +EXPORT_SYMBOL_GPL(l3mdev_master_upper_ifindex_by_index_rcu);
>> +
>> /**
>> * l3mdev_fib_table - get FIB table id associated with an L3
>> * master interface
