batman-adv: Add get_ethtool_stats() support

Added additional counters in a bat_stats structure, which are exported
through the ethtool api. The counters are specific to batman-adv and
includes:
 forwarded packets and bytes
 management packets and bytes (aggregated OGMs at this point)
 translation table packets

New counters are added by extending "enum bat_counters" in types.h and
adding corresponding  descriptive string(s) to bat_counters_strings in
soft-iface.c.

Counters are increased by calling batadv_add_counter() and incremented
by one by calling batadv_inc_counter().

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 015471d..369604c 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -600,6 +600,8 @@
 
 	switch (tt_query->flags & TT_QUERY_TYPE_MASK) {
 	case TT_REQUEST:
+		batadv_inc_counter(bat_priv, BAT_CNT_TT_REQUEST_RX);
+
 		/* If we cannot provide an answer the tt_request is
 		 * forwarded */
 		if (!send_tt_response(bat_priv, tt_query)) {
@@ -612,6 +614,8 @@
 		}
 		break;
 	case TT_RESPONSE:
+		batadv_inc_counter(bat_priv, BAT_CNT_TT_RESPONSE_RX);
+
 		if (is_my_mac(tt_query->dst)) {
 			/* packet needs to be linearized to access the TT
 			 * changes */
@@ -665,6 +669,8 @@
 	if (is_broadcast_ether_addr(ethhdr->h_source))
 		goto out;
 
+	batadv_inc_counter(bat_priv, BAT_CNT_TT_ROAM_ADV_RX);
+
 	roam_adv_packet = (struct roam_adv_packet *)skb->data;
 
 	if (!is_my_mac(roam_adv_packet->dst))
@@ -872,6 +878,11 @@
 	/* decrement ttl */
 	unicast_packet->header.ttl--;
 
+	/* Update stats counter */
+	batadv_inc_counter(bat_priv, BAT_CNT_FORWARD);
+	batadv_add_counter(bat_priv, BAT_CNT_FORWARD_BYTES,
+			   skb->len + ETH_HLEN);
+
 	/* route it */
 	send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
 	ret = NET_RX_SUCCESS;