[RFC 2/5] mac80211: export minstrel best rate information in set_sta_info()

[Antonio Quartulli <antonio@meshcoding.com>]

From: Antonio Quartulli <antonio@open-mesh.com>

Add the get_minstrel_best_rate() RC API in order to retrieve
the rate having the highest throughput. If the RC algorithm
implements such API, then fill the related field in
station_info when dumping a station.

This API is supposed to be implemented by Minstrel only.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
---
 include/net/mac80211.h | 15 +++++++++++++++
 net/mac80211/cfg.c     | 15 +++++++++++++++
 2 files changed, 30 insertions(+)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index df1004b..9ed56f8 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -4452,6 +4452,17 @@ struct ieee80211_tx_rate_control {
 	bool bss;
 };
 
+/**
+ * struct ieee80211_minstrel_rate_info - rate information extracted from
+ *  the Minstrel RC algorithm
+ * @rate: the reported bitrate
+ * @prob: probability of success of rate computed by Minstrel
+ */
+struct ieee80211_minstrel_rate_info {
+	struct ieee80211_tx_rate rate;
+	u32 prob;
+};
+
 struct rate_control_ops {
 	struct module *module;
 	const char *name;
@@ -4478,6 +4489,10 @@ struct rate_control_ops {
 	void (*add_sta_debugfs)(void *priv, void *priv_sta,
 				struct dentry *dir);
 	void (*remove_sta_debugfs)(void *priv, void *priv_sta);
+
+	void (*get_minstrel_best_rate)
+		(void *priv, void *priv_sta,
+		 struct ieee80211_minstrel_rate_info *info);
 };
 
 static inline int rate_supported(struct ieee80211_sta *sta,
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 032081c..c0d394c 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -463,6 +463,9 @@ static void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
 {
 	struct ieee80211_sub_if_data *sdata = sta->sdata;
 	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_minstrel_rate_info info;
+	struct rate_control_ref *ref = local->rate_ctrl;
+	struct rate_info rinfo;
 	struct timespec uptime;
 	u64 packets = 0;
 	int i, ac;
@@ -578,6 +581,18 @@ static void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo)
 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_ASSOCIATED);
 	if (test_sta_flag(sta, WLAN_STA_TDLS_PEER))
 		sinfo->sta_flags.set |= BIT(NL80211_STA_FLAG_TDLS_PEER);
+
+	if (!ref->ops->get_minstrel_best_rate)
+		return;
+
+	sinfo->filled |= STATION_INFO_MINSTREL_BEST_RATE;
+
+	ref->ops->get_minstrel_best_rate(ref->priv, sta->rate_ctrl_priv, &info);
+
+	sta_set_rate_info_tx(sta, &info.rate, &rinfo);
+
+	sinfo->minstrel_best_rate.bitrate = cfg80211_calculate_bitrate(&rinfo);
+	sinfo->minstrel_best_rate.prob = info.prob;
 }
 
 static const char ieee80211_gstrings_sta_stats[][ETH_GSTRING_LEN] = {
-- 
1.8.5.3