{nl,mac}80211: report gate connectivity in station info

Capture the current state of gate connectivity from the mesh
formation field in mesh config whenever we receive a beacon,
and report that via GET_STATION.  This allows applications
doing mesh peering in userspace to make peering decisions
based on peers' current upstream connectivity.

Signed-off-by: Bob Copeland <bobcopeland@fb.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

include/linux/ieee80211.h

@@ -812,6 +812,8 @@ enum mesh_config_capab_flags {
 	IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL	= 0x40,
 };
 
+#define IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE 0x1
+
 /**
  * mesh channel switch parameters element's flag indicator
  *

include/net/cfg80211.h

@@ -1296,6 +1296,7 @@ struct cfg80211_tid_stats {
  * @rx_beacon: number of beacons received from this peer
  * @rx_beacon_signal_avg: signal strength average (in dBm) for beacons received
  *	from this peer
+ * @connected_to_gate: true if mesh STA has a path to mesh gate
  * @rx_duration: aggregate PPDU duration(usecs) for all the frames from a peer
  * @pertid: per-TID statistics, see &struct cfg80211_tid_stats, using the last
  *	(IEEE80211_NUM_TIDS) index for MSDUs not encapsulated in QoS-MPDUs.
@@ -1350,6 +1351,8 @@ struct station_info {
 	u64 rx_beacon;
 	u64 rx_duration;
 	u8 rx_beacon_signal_avg;
+	u8 connected_to_gate;
+
 	struct cfg80211_tid_stats *pertid;
 	s8 ack_signal;
 	s8 avg_ack_signal;

include/uapi/linux/nl80211.h

@@ -3116,6 +3116,8 @@ enum nl80211_sta_bss_param {
  *	with an FCS error (u32, from this station). This count may not include
  *	some packets with an FCS error due to TA corruption. Hence this counter
  *	might not be fully accurate.
+ * @NL80211_STA_INFO_CONNECTED_TO_GATE: set to true if STA has a path to a
+ *	mesh gate
  * @__NL80211_STA_INFO_AFTER_LAST: internal
  * @NL80211_STA_INFO_MAX: highest possible station info attribute
  */
@@ -3158,6 +3160,7 @@ enum nl80211_sta_info {
 	NL80211_STA_INFO_ACK_SIGNAL_AVG,
 	NL80211_STA_INFO_RX_MPDUS,
 	NL80211_STA_INFO_FCS_ERROR_COUNT,
+	NL80211_STA_INFO_CONNECTED_TO_GATE,
 
 	/* keep last */
 	__NL80211_STA_INFO_AFTER_LAST,

net/mac80211/mesh_plink.c

@@ -590,6 +590,9 @@ void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
 	if (!sta)
 		goto out;
 
+	sta->mesh->connected_to_gate = elems->mesh_config->meshconf_form &
+		IEEE80211_MESHCONF_FORM_CONNECTED_TO_GATE;
+
 	if (mesh_peer_accepts_plinks(elems) &&
 	    sta->mesh->plink_state == NL80211_PLINK_LISTEN &&
 	    sdata->u.mesh.accepting_plinks &&

net/mac80211/sta_info.c

@@ -2264,7 +2264,8 @@ void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo,
 				 BIT_ULL(NL80211_STA_INFO_PLINK_STATE) |
 				 BIT_ULL(NL80211_STA_INFO_LOCAL_PM) |
 				 BIT_ULL(NL80211_STA_INFO_PEER_PM) |
-				 BIT_ULL(NL80211_STA_INFO_NONPEER_PM);
+				 BIT_ULL(NL80211_STA_INFO_NONPEER_PM) |
+				 BIT_ULL(NL80211_STA_INFO_CONNECTED_TO_GATE);
 
 		sinfo->llid = sta->mesh->llid;
 		sinfo->plid = sta->mesh->plid;
@@ -2276,6 +2277,7 @@ void sta_set_sinfo(struct sta_info *sta, struct station_info *sinfo,
 		sinfo->local_pm = sta->mesh->local_pm;
 		sinfo->peer_pm = sta->mesh->peer_pm;
 		sinfo->nonpeer_pm = sta->mesh->nonpeer_pm;
+		sinfo->connected_to_gate = sta->mesh->connected_to_gate;
 #endif
 	}
 

net/mac80211/sta_info.h

@@ -364,6 +364,7 @@ DECLARE_EWMA(mesh_fail_avg, 20, 8)
  * @nonpeer_pm: STA power save mode towards non-peer neighbors
  * @processed_beacon: set to true after peer rates and capabilities are
  *	processed
+ * @connected_to_gate: true if mesh STA has a path to a mesh gate
  * @fail_avg: moving percentage of failed MSDUs
  */
 struct mesh_sta {
@@ -381,6 +382,7 @@ struct mesh_sta {
 	u8 plink_retries;
 
 	bool processed_beacon;
+	bool connected_to_gate;
 
 	enum nl80211_plink_state plink_state;
 	u32 plink_timeout;

net/wireless/nl80211.c

@@ -4883,6 +4883,7 @@ static int nl80211_send_station(struct sk_buff *msg, u32 cmd, u32 portid,
 	PUT_SINFO(LOCAL_PM, local_pm, u32);
 	PUT_SINFO(PEER_PM, peer_pm, u32);
 	PUT_SINFO(NONPEER_PM, nonpeer_pm, u32);
+	PUT_SINFO(CONNECTED_TO_GATE, connected_to_gate, u8);
 
 	if (sinfo->filled & BIT_ULL(NL80211_STA_INFO_BSS_PARAM)) {
 		bss_param = nla_nest_start(msg, NL80211_STA_INFO_BSS_PARAM);