On Mon, 14 Oct 2019 12:49:52 +0200, Lorenzo Bianconi wrote: > @@ -3983,6 +4071,46 @@ static int mvneta_ioctl(struct net_device *dev, struct > ifreq *ifr, int cmd) > return phylink_mii_ioctl(pp->phylink, ifr, cmd); > } > > +static int mvneta_xdp_setup(struct net_device *dev, struct bpf_prog *prog, > + struct netlink_ext_ack *extack) > +{ > + struct mvneta_port *pp = netdev_priv(dev); > + struct bpf_prog *old_prog; > + > + if (prog && dev->mtu > MVNETA_MAX_RX_BUF_SIZE) { > + NL_SET_ERR_MSG_MOD(extack, "Jumbo frames not supported on XDP"); > + return -EOPNOTSUPP; > + } > + > + if (netif_running(dev)) > + mvneta_stop(dev); > + > + old_prog = xchg(&pp->xdp_prog, prog); > + if (old_prog) > + bpf_prog_put(old_prog); > + > + if (netif_running(dev)) > + mvneta_open(dev);
Ah, the stopping and starting of the interface is sad. If start fails the interface is left in a funky state until someone does a stop/start cycle. Not that you introduced that. > + return 0; > +} > + > +static int mvneta_xdp(struct net_device *dev, struct netdev_bpf *xdp) > +{ > + struct mvneta_port *pp = netdev_priv(dev); > + > + switch (xdp->command) { > + case XDP_SETUP_PROG: > + return mvneta_xdp_setup(dev, xdp->prog, xdp->extack); > + case XDP_QUERY_PROG: > + xdp->prog_id = pp->xdp_prog ? pp->xdp_prog->aux->id : 0; > + return 0; > + default: > + NL_SET_ERR_MSG_MOD(xdp->extack, "unknown XDP command"); Please drop this message here, there are commands you legitimately don't care about, just return -EINVAL, no need to risk leaking a meaningless warning to the user space. > + return -EINVAL; > + } > +}