tree 76ba2be2cdb8d5a01fa43270a66fdbf758837f99
parent 59a308967589f5b3f1f42793ab49bc2e18069769
author Jesper Dangaard Brouer <brouer@redhat.com> 1504017486 +0200
committer David S. Miller <davem@davemloft.net> 1504029089 -0700

samples/bpf: xdp_redirect load XDP dummy prog on TX device

For supporting XDP_REDIRECT, a device driver must (obviously)
implement the "TX" function ndo_xdp_xmit().  An additional requirement
is you cannot TX out a device, unless it also have a xdp bpf program
attached. This dependency is caused by the driver code need to setup
XDP resources before it can ndo_xdp_xmit.

Update bpf samples xdp_redirect and xdp_redirect_map to automatically
attach a dummy XDP program to the configured ifindex_out device.  Use
the XDP flag XDP_FLAGS_UPDATE_IF_NOEXIST on the dummy load, to avoid
overriding an existing XDP prog on the device.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>