From e45a4fed9d006480a5cc2312d5d4f7988a3a655e Mon Sep 17 00:00:00 2001 From: Charles McLachlan Date: Thu, 31 Oct 2019 10:23:37 +0000 Subject: sfc: Enable setting of xdp_prog Provide an ndo_bpf function to efx_netdev_ops that allows setting and querying of xdp programs on an interface. Also check that the MTU size isn't too big when setting a program or when the MTU is explicitly set. Signed-off-by: Charles McLachlan Acked-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- drivers/net/ethernet/sfc/efx.c | 70 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) (limited to 'drivers') diff --git a/drivers/net/ethernet/sfc/efx.c b/drivers/net/ethernet/sfc/efx.c index bd0424414781..429fb268b0da 100644 --- a/drivers/net/ethernet/sfc/efx.c +++ b/drivers/net/ethernet/sfc/efx.c @@ -226,6 +226,8 @@ static void efx_fini_napi_channel(struct efx_channel *channel); static void efx_fini_struct(struct efx_nic *efx); static void efx_start_all(struct efx_nic *efx); static void efx_stop_all(struct efx_nic *efx); +static int efx_xdp_setup_prog(struct efx_nic *efx, struct bpf_prog *prog); +static int efx_xdp(struct net_device *dev, struct netdev_bpf *xdp); #define EFX_ASSERT_RESET_SERIALISED(efx) \ do { \ @@ -2025,6 +2027,10 @@ static void efx_stop_all(struct efx_nic *efx) static void efx_remove_all(struct efx_nic *efx) { + rtnl_lock(); + efx_xdp_setup_prog(efx, NULL); + rtnl_unlock(); + efx_remove_channels(efx); efx_remove_filters(efx); #ifdef CONFIG_SFC_SRIOV @@ -2280,6 +2286,17 @@ static void efx_watchdog(struct net_device *net_dev) efx_schedule_reset(efx, RESET_TYPE_TX_WATCHDOG); } +static unsigned int efx_xdp_max_mtu(struct efx_nic *efx) +{ + /* The maximum MTU that we can fit in a single page, allowing for + * framing, overhead and XDP headroom. + */ + int overhead = EFX_MAX_FRAME_LEN(0) + sizeof(struct efx_rx_page_state) + + efx->rx_prefix_size + efx->type->rx_buffer_padding + + efx->rx_ip_align + XDP_PACKET_HEADROOM; + + return PAGE_SIZE - overhead; +} /* Context: process, rtnl_lock() held. */ static int efx_change_mtu(struct net_device *net_dev, int new_mtu) @@ -2291,6 +2308,14 @@ static int efx_change_mtu(struct net_device *net_dev, int new_mtu) if (rc) return rc; + if (rtnl_dereference(efx->xdp_prog) && + new_mtu > efx_xdp_max_mtu(efx)) { + netif_err(efx, drv, efx->net_dev, + "Requested MTU of %d too big for XDP (max: %d)\n", + new_mtu, efx_xdp_max_mtu(efx)); + return -EINVAL; + } + netif_dbg(efx, drv, efx->net_dev, "changing MTU to %d\n", new_mtu); efx_device_detach_sync(efx); @@ -2492,8 +2517,53 @@ static const struct net_device_ops efx_netdev_ops = { #endif .ndo_udp_tunnel_add = efx_udp_tunnel_add, .ndo_udp_tunnel_del = efx_udp_tunnel_del, + .ndo_bpf = efx_xdp }; +static int efx_xdp_setup_prog(struct efx_nic *efx, struct bpf_prog *prog) +{ + struct bpf_prog *old_prog; + + if (efx->xdp_rxq_info_failed) { + netif_err(efx, drv, efx->net_dev, + "Unable to bind XDP program due to previous failure of rxq_info\n"); + return -EINVAL; + } + + if (prog && efx->net_dev->mtu > efx_xdp_max_mtu(efx)) { + netif_err(efx, drv, efx->net_dev, + "Unable to configure XDP with MTU of %d (max: %d)\n", + efx->net_dev->mtu, efx_xdp_max_mtu(efx)); + return -EINVAL; + } + + old_prog = rtnl_dereference(efx->xdp_prog); + rcu_assign_pointer(efx->xdp_prog, prog); + /* Release the reference that was originally passed by the caller. */ + if (old_prog) + bpf_prog_put(old_prog); + + return 0; +} + +/* Context: process, rtnl_lock() held. */ +static int efx_xdp(struct net_device *dev, struct netdev_bpf *xdp) +{ + struct efx_nic *efx = netdev_priv(dev); + struct bpf_prog *xdp_prog; + + switch (xdp->command) { + case XDP_SETUP_PROG: + return efx_xdp_setup_prog(efx, xdp->prog); + case XDP_QUERY_PROG: + xdp_prog = rtnl_dereference(efx->xdp_prog); + xdp->prog_id = xdp_prog ? xdp_prog->aux->id : 0; + return 0; + default: + return -EINVAL; + } +} + static void efx_update_name(struct efx_nic *efx) { strcpy(efx->name, efx->net_dev->name); -- cgit v1.2.3