mac80211: add sta_state callback

(based on Eliad's patch)

Add a callback to notify the low-level driver whenever
the state of a station changes. The driver is only
notified when the station is actually in the mac80211
hash table, not for pre-insert state transitions.

To allow the driver to replace sta_add/remove calls
with this, call extra transitions with the NOTEXIST
state.

This callback can fail, so we need to be careful in
handling it when a station is inserted, particularly
in the IBSS case where we still keep the station entry
around for mac80211 purposes.

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 22 insertions, 0 deletions

diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h
index b8673f6100df..4bd266ec5333 100644
--- a/net/mac80211/driver-ops.h
+++ b/net/mac80211/driver-ops.h
@@ -478,6 +478,28 @@ static inline void drv_sta_remove(struct ieee80211_local *local,
 	trace_drv_return_void(local);
 }
 
+static inline __must_check
+int drv_sta_state(struct ieee80211_local *local,
+		  struct ieee80211_sub_if_data *sdata,
+		  struct sta_info *sta,
+		  enum ieee80211_sta_state old_state,
+		  enum ieee80211_sta_state new_state)
+{
+	int ret = 0;
+
+	might_sleep();
+
+	sdata = get_bss_sdata(sdata);
+	check_sdata_in_driver(sdata);
+
+	trace_drv_sta_state(local, sdata, &sta->sta, old_state, new_state);
+	if (local->ops->sta_state)
+		ret = local->ops->sta_state(&local->hw, &sdata->vif, &sta->sta,
+					    old_state, new_state);
+	trace_drv_return_int(local, ret);
+	return ret;
+}
+
 static inline int drv_conf_tx(struct ieee80211_local *local,
 			      struct ieee80211_sub_if_data *sdata, u16 queue,
 			      const struct ieee80211_tx_queue_params *params)