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/types.h b/net/batman-adv/types.h
index 547dc33..6b569de 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -148,9 +148,26 @@
 };
 #endif
 
+enum bat_counters {
+	BAT_CNT_FORWARD,
+	BAT_CNT_FORWARD_BYTES,
+	BAT_CNT_MGMT_TX,
+	BAT_CNT_MGMT_TX_BYTES,
+	BAT_CNT_MGMT_RX,
+	BAT_CNT_MGMT_RX_BYTES,
+	BAT_CNT_TT_REQUEST_TX,
+	BAT_CNT_TT_REQUEST_RX,
+	BAT_CNT_TT_RESPONSE_TX,
+	BAT_CNT_TT_RESPONSE_RX,
+	BAT_CNT_TT_ROAM_ADV_TX,
+	BAT_CNT_TT_ROAM_ADV_RX,
+	BAT_CNT_NUM,
+};
+
 struct bat_priv {
 	atomic_t mesh_state;
 	struct net_device_stats stats;
+	uint64_t __percpu *bat_counters; /* Per cpu counters */
 	atomic_t aggregated_ogms;	/* boolean */
 	atomic_t bonding;		/* boolean */
 	atomic_t fragmentation;		/* boolean */