On 9/23/25 12:35, Yureka Lilian wrote: > The xdp-forwarder's purpose is implementing the functionality needed > within the net-vm (a VM running the Linux drivers for any physical > interfaces on the spectrum system). > > In the future, the net-vm will load the included XDP programs on the > passed-through physical interfaces as well as the downstream virtio > interface going into the router (recognized by its special MAC address). > > The net-vm needs to multiplex between the physical interfaces, as there > might be several interfaces in the same IOMMU-group. > > For this, the XDP program loaded on the physical interfaces > (`prog_physical.o`) applies a VLAN tag corresponding to the interface id > and redirects the packets to the router interface (identified by the > `router_iface` bpf map). In the other direction the XDP program loaded on > the router interface (`prog_router.o`) removes one layer of VLAN tagging > and redirects the packets to the interface read from the VLAN tag. > > The helper program `set_router_iface` is used to update the `router_iface` > bpf map to point to the interface passed as argument to the program. > > Co-authored-by: Demi Marie Obenour > Signed-off-by: Yureka Lilian Signed-off-by: Demi Marie Obenour -- Sincerely, Demi Marie Obenour (she/her/hers)