ipvlan: fix device features

Processing NETDEV_FEAT_CHANGE causes IPvlan links to lose
NETIF_F_LLTX feature because of the incorrect handling of
features in ipvlan_fix_features().

--before--
lpaa10:~# ethtool -k ipvl0 | grep tx-lockless
tx-lockless: on [fixed]
lpaa10:~# ethtool -K ipvl0 tso off
Cannot change tcp-segmentation-offload
Actual changes:
vlan-challenged: off [fixed]
tx-lockless: off [fixed]
lpaa10:~# ethtool -k ipvl0 | grep tx-lockless
tx-lockless: off [fixed]
lpaa10:~#

--after--
lpaa10:~# ethtool -k ipvl0 | grep tx-lockless
tx-lockless: on [fixed]
lpaa10:~# ethtool -K ipvl0 tso off
Cannot change tcp-segmentation-offload
Could not change any device features
lpaa10:~# ethtool -k ipvl0 | grep tx-lockless
tx-lockless: on [fixed]
lpaa10:~#

Fixes: 2ad7bf36 ("ipvlan: Initial check-in of the IPVLAN driver.")
Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ipvlan/ipvlan_main.c

@@ -106,12 +106,21 @@ static void ipvlan_port_destroy(struct net_device *dev)
 	kfree(port);
 }
 
+#define IPVLAN_ALWAYS_ON_OFLOADS \
+	(NETIF_F_SG | NETIF_F_HW_CSUM | \
+	 NETIF_F_GSO_ROBUST | NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL)
+
+#define IPVLAN_ALWAYS_ON \
+	(IPVLAN_ALWAYS_ON_OFLOADS | NETIF_F_LLTX | NETIF_F_VLAN_CHALLENGED)
+
 #define IPVLAN_FEATURES \
-	(NETIF_F_SG | NETIF_F_CSUM_MASK | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
+	(NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \
 	 NETIF_F_GSO | NETIF_F_ALL_TSO | NETIF_F_GSO_ROBUST | \
 	 NETIF_F_GRO | NETIF_F_RXCSUM | \
 	 NETIF_F_HW_VLAN_CTAG_FILTER | NETIF_F_HW_VLAN_STAG_FILTER)
 
+	/* NETIF_F_GSO_ENCAP_ALL NETIF_F_GSO_SOFTWARE Newly added */
+
 #define IPVLAN_STATE_MASK \
 	((1<<__LINK_STATE_NOCARRIER) | (1<<__LINK_STATE_DORMANT))
 
@@ -125,7 +134,9 @@ static int ipvlan_init(struct net_device *dev)
 	dev->state = (dev->state & ~IPVLAN_STATE_MASK) |
 		     (phy_dev->state & IPVLAN_STATE_MASK);
 	dev->features = phy_dev->features & IPVLAN_FEATURES;
-	dev->features |= NETIF_F_LLTX | NETIF_F_VLAN_CHALLENGED;
+	dev->features |= IPVLAN_ALWAYS_ON;
+	dev->vlan_features = phy_dev->vlan_features & IPVLAN_FEATURES;
+	dev->vlan_features |= IPVLAN_ALWAYS_ON_OFLOADS;
 	dev->hw_enc_features |= dev->features;
 	dev->gso_max_size = phy_dev->gso_max_size;
 	dev->gso_max_segs = phy_dev->gso_max_segs;
@@ -227,7 +238,14 @@ static netdev_features_t ipvlan_fix_features(struct net_device *dev,
 {
 	struct ipvl_dev *ipvlan = netdev_priv(dev);
 
-	return features & (ipvlan->sfeatures | ~IPVLAN_FEATURES);
+	features |= NETIF_F_ALL_FOR_ALL;
+	features &= (ipvlan->sfeatures | ~IPVLAN_FEATURES);
+	features = netdev_increment_features(ipvlan->phy_dev->features,
+					     features, features);
+	features |= IPVLAN_ALWAYS_ON;
+	features &= (IPVLAN_FEATURES | IPVLAN_ALWAYS_ON);
+
+	return features;
 }
 
 static void ipvlan_change_rx_flags(struct net_device *dev, int change)
@@ -734,10 +752,9 @@ static int ipvlan_device_event(struct notifier_block *unused,
 
 	case NETDEV_FEAT_CHANGE:
 		list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
-			ipvlan->dev->features = dev->features & IPVLAN_FEATURES;
 			ipvlan->dev->gso_max_size = dev->gso_max_size;
 			ipvlan->dev->gso_max_segs = dev->gso_max_segs;
-			netdev_features_change(ipvlan->dev);
+			netdev_update_features(ipvlan->dev);
 		}
 		break;