mac80211: Support getting sta_info stats via ethtool.

This lets ethtool print out stats related to stations
connected to the interface.  Does not yet get stats
from the underlying driver.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

net/mac80211/cfg.c

@@ -450,6 +450,94 @@ static void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER);
 }
 
+static const char ieee80211_gstrings_sta_stats[][ETH_GSTRING_LEN] = {
+	"rx_packets", "rx_bytes", "wep_weak_iv_count",
+	"rx_duplicates", "rx_fragments", "rx_dropped",
+	"tx_packets", "tx_bytes", "tx_fragments",
+	"tx_filtered", "tx_retry_failed", "tx_retries",
+	"beacon_loss"
+};
+#define STA_STATS_LEN	ARRAY_SIZE(ieee80211_gstrings_sta_stats)
+
+static int ieee80211_get_et_sset_count(struct wiphy *wiphy,
+				       struct net_device *dev,
+				       int sset)
+{
+	if (sset == ETH_SS_STATS)
+		return STA_STATS_LEN;
+
+	return -EOPNOTSUPP;
+}
+
+static void ieee80211_get_et_stats(struct wiphy *wiphy,
+				   struct net_device *dev,
+				   struct ethtool_stats *stats,
+				   u64 *data)
+{
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	struct sta_info *sta;
+	struct ieee80211_local *local = sdata->local;
+	int i;
+
+	memset(data, 0, sizeof(u64) * STA_STATS_LEN);
+
+#define ADD_STA_STATS(sta)				\
+	do {						\
+		data[i++] += sta->rx_packets;		\
+		data[i++] += sta->rx_bytes;		\
+		data[i++] += sta->wep_weak_iv_count;	\
+		data[i++] += sta->num_duplicates;	\
+		data[i++] += sta->rx_fragments;		\
+		data[i++] += sta->rx_dropped;		\
+							\
+		data[i++] += sta->tx_packets;		\
+		data[i++] += sta->tx_bytes;		\
+		data[i++] += sta->tx_fragments;		\
+		data[i++] += sta->tx_filtered_count;	\
+		data[i++] += sta->tx_retry_failed;	\
+		data[i++] += sta->tx_retry_count;	\
+		data[i++] += sta->beacon_loss_count;	\
+	} while (0)
+
+	/* For Managed stations, find the single station based on BSSID
+	 * and use that.  For interface types, iterate through all available
+	 * stations and add stats for any station that is assigned to this
+	 * network device.
+	 */
+
+	rcu_read_lock();
+
+	if (sdata->vif.type == NL80211_IFTYPE_STATION) {
+		sta = sta_info_get_bss(sdata, sdata->u.mgd.bssid);
+		if (sta && !WARN_ON(sta->sdata->dev != dev)) {
+			i = 0;
+			ADD_STA_STATS(sta);
+			BUG_ON(i != STA_STATS_LEN);
+		}
+	} else {
+		list_for_each_entry_rcu(sta, &local->sta_list, list) {
+			/* Make sure this station belongs to the proper dev */
+			if (sta->sdata->dev != dev)
+				continue;
+
+			i = 0;
+			ADD_STA_STATS(sta);
+			BUG_ON(i != STA_STATS_LEN);
+		}
+	}
+
+	rcu_read_unlock();
+}
+
+static void ieee80211_get_et_strings(struct wiphy *wiphy,
+				     struct net_device *dev,
+				     u32 sset, u8 *data)
+{
+	if (sset == ETH_SS_STATS) {
+		int sz_sta_stats = sizeof(ieee80211_gstrings_sta_stats);
+		memcpy(data, *ieee80211_gstrings_sta_stats, sz_sta_stats);
+	}
+}
 
 static int ieee80211_dump_station(struct wiphy *wiphy, struct net_device *dev,
 				 int idx, u8 *mac, struct station_info *sinfo)
@@ -2794,4 +2882,7 @@ struct cfg80211_ops mac80211_config_ops = {
 #ifdef CONFIG_PM
 	.set_wakeup = ieee80211_set_wakeup,
 #endif
+	.get_et_sset_count = ieee80211_get_et_sset_count,
+	.get_et_stats = ieee80211_get_et_stats,
+	.get_et_strings = ieee80211_get_et_strings,
 };