+/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
+int br_min_mtu(const struct net_bridge *br)
+{
+ const struct net_bridge_port *p;
+ int mtu = 0;
+
+ ASSERT_RTNL();
+
+ if (list_empty(&br->port_list))
+ mtu = ETH_DATA_LEN;
+ else {
+ list_for_each_entry(p, &br->port_list, list) {
+ if (!mtu || p->dev->mtu < mtu)
+ mtu = p->dev->mtu;
+ }
+ }
+ return mtu;
+}
+
+/*
+ * Recomputes features using slave's features
+ */
+void br_features_recompute(struct net_bridge *br)
+{
+ struct net_bridge_port *p;
+ unsigned long features, checksum;
+
+ checksum = br->feature_mask & NETIF_F_ALL_CSUM ? NETIF_F_NO_CSUM : 0;
+ features = br->feature_mask & ~NETIF_F_ALL_CSUM;
+
+ list_for_each_entry(p, &br->port_list, list) {
+ unsigned long feature = p->dev->features;
+
+ if (checksum & NETIF_F_NO_CSUM && !(feature & NETIF_F_NO_CSUM))
+ checksum ^= NETIF_F_NO_CSUM | NETIF_F_HW_CSUM;
+ if (checksum & NETIF_F_HW_CSUM && !(feature & NETIF_F_HW_CSUM))
+ checksum ^= NETIF_F_HW_CSUM | NETIF_F_IP_CSUM;
+ if (!(feature & NETIF_F_IP_CSUM))
+ checksum = 0;
+
+ if (feature & NETIF_F_GSO)
+ feature |= NETIF_F_GSO_SOFTWARE;
+ feature |= NETIF_F_GSO;
+
+ features &= feature;
+ }
+
+ if (!(checksum & NETIF_F_ALL_CSUM))
+ features &= ~NETIF_F_SG;
+ if (!(features & NETIF_F_SG))
+ features &= ~NETIF_F_GSO_MASK;
+
+ br->dev->features = features | checksum | NETIF_F_LLTX |
+ NETIF_F_GSO_ROBUST;
+}
+
+/* called with RTNL */