Staging: batman-adv: layer2 unicast packet fragmentation

[firefly-linux-kernel-4.4.55.git] / drivers / staging / batman-adv / hard-interface.c

diff --git a/drivers/staging/batman-adv/hard-interface.c b/drivers/staging/batman-adv/hard-interface.c
index 6e973a79aa25b6fec509639687fc4e196a568397..82d3d554467ba007f558afe3498f41b6bc4dabfb 100644 (file)
--- a/drivers/staging/batman-adv/hard-interface.c
+++ b/drivers/staging/batman-adv/hard-interface.c
@@ -166,6 +166,11 @@ int hardif_min_mtu(void)
        /* allow big frames if all devices are capable to do so
         * (have MTU > 1500 + BAT_HEADER_LEN) */
        int min_mtu = ETH_DATA_LEN;
+       /* FIXME: each batman_if will be attached to a softif */
+       struct bat_priv *bat_priv = netdev_priv(soft_device);
+
+       if (atomic_read(&bat_priv->frag_enabled))
+               goto out;
 
        rcu_read_lock();
        list_for_each_entry_rcu(batman_if, &if_list, list) {
@@ -175,7 +180,7 @@ int hardif_min_mtu(void)
                                      min_mtu);
        }
        rcu_read_unlock();
-
+out:
        return min_mtu;
 }
 
@@ -261,8 +266,30 @@ int hardif_enable_interface(struct batman_if *batman_if)
        orig_hash_add_if(batman_if, bat_priv->num_ifaces);
 
        atomic_set(&batman_if->seqno, 1);
+       atomic_set(&batman_if->frag_seqno, 1);
        bat_info(soft_device, "Adding interface: %s\n", batman_if->dev);
 
+       if (atomic_read(&bat_priv->frag_enabled) && batman_if->net_dev->mtu <
+               ETH_DATA_LEN + BAT_HEADER_LEN)
+               bat_info(soft_device,
+                       "The MTU of interface %s is too small (%i) to handle "
+                       "the transport of batman-adv packets. Packets going "
+                       "over this interface will be fragmented on layer2 "
+                       "which could impact the performance. Setting the MTU "
+                       "to %zi would solve the problem.\n",
+                       batman_if->dev, batman_if->net_dev->mtu,
+                       ETH_DATA_LEN + BAT_HEADER_LEN);
+
+       if (!atomic_read(&bat_priv->frag_enabled) && batman_if->net_dev->mtu <
+               ETH_DATA_LEN + BAT_HEADER_LEN)
+               bat_info(soft_device,
+                       "The MTU of interface %s is too small (%i) to handle "
+                       "the transport of batman-adv packets. If you experience"
+                       " problems getting traffic through try increasing the "
+                       "MTU to %zi.\n",
+                       batman_if->dev, batman_if->net_dev->mtu,
+                       ETH_DATA_LEN + BAT_HEADER_LEN);
+
        if (hardif_is_iface_up(batman_if))
                hardif_activate_interface(soft_device, bat_priv, batman_if);
        else
@@ -495,6 +522,11 @@ int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
                ret = recv_unicast_packet(skb, batman_if);
                break;
 
+               /* fragmented unicast packet */
+       case BAT_UNICAST_FRAG:
+               ret = recv_ucast_frag_packet(skb, batman_if);
+               break;
+
                /* broadcast packet */
        case BAT_BCAST:
                ret = recv_bcast_packet(skb);