macvtap: Let TUNSETOFFLOAD actually controll offload features.

When the user issues TUNSETOFFLOAD ioctl, macvtap does not do
anything other then to verify arguments.  This patch adds
functionality to allow users to actually control offload features.
NETIF_F_GSO and NETIF_F_GRO are always on, but the rest of the
features can be controlled.

Signed-off-by: Vlad Yasevich <vyasevic@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 10 insertions, 0 deletions

diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index d811b06e2ccd..18373b6ae37d 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -638,6 +638,14 @@ static int macvlan_ethtool_get_settings(struct net_device *dev,
         return __ethtool_get_settings(vlan->lowerdev, cmd);
 }
 
+static netdev_features_t macvlan_fix_features(struct net_device *dev,
+                                              netdev_features_t features)
+{
+        struct macvlan_dev *vlan = netdev_priv(dev);
+
+        return features & (vlan->set_features | ~MACVLAN_FEATURES);
+}
+
 static const struct ethtool_ops macvlan_ethtool_ops = {
         .get_link               = ethtool_op_get_link,
         .get_settings           = macvlan_ethtool_get_settings,
@@ -651,6 +659,7 @@ static const struct net_device_ops macvlan_netdev_ops = {
         .ndo_stop               = macvlan_stop,
         .ndo_start_xmit         = macvlan_start_xmit,
         .ndo_change_mtu         = macvlan_change_mtu,
+        .ndo_fix_features       = macvlan_fix_features,
         .ndo_change_rx_flags    = macvlan_change_rx_flags,
         .ndo_set_mac_address    = macvlan_set_mac_address,
         .ndo_set_rx_mode        = macvlan_set_mac_lists,
@@ -791,6 +800,7 @@ int macvlan_common_newlink(struct net *src_net, struct net_device *dev,
         vlan->port     = port;
         vlan->receive  = receive;
         vlan->forward  = forward;
+        vlan->set_features = MACVLAN_FEATURES;
 
         vlan->mode     = MACVLAN_MODE_VEPA;
         if (data && data[IFLA_MACVLAN_MODE])