linux

net: Introduce net_failover driver The net_failover driver provides an automated failover mechanism via APIs to create and destroy a failover master netdev and manages a primary and standby slave netdevs that get registered via the generic failover infrastructure. The failover netdev acts a master device and controls 2 slave devices. The original paravirtual interface gets registered as 'standby' slave netdev and a passthru/vf device with the same MAC gets registered as 'primary' slave netdev. Both 'standby' and 'failover' netdevs are associated with the same 'pci' device. The user accesses the network interface via 'failover' netdev. The 'failover' netdev chooses 'primary' netdev as default for transmits when it is available with link up and running. This can be used by paravirtual drivers to enable an alternate low latency datapath. It also enables hypervisor controlled live migration of a VM with direct attached VF by failing over to the paravirtual datapath when the VF is unplugged. Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> 2018-05-24 09:55:15 -07:00