Drivers may at times want to iterate their stations with a function
which requires some non-atomic operations.
ieee80211_iterate_stations_mtx() introduces an API to iterate stations
while holding that wiphy's mutex. This allows the iterating function to
do non-atomic operations safely.
Signed-off-by: Rory Little <rory@xxxxxxxxxxxxxxx>
---
include/net/mac80211.h | 18 ++++++++++++++++++
net/mac80211/util.c | 30 ++++++++++++++++++++++++++++++
2 files changed, 48 insertions(+)
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index e1580360e099..6c8a2dd53243 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -6313,6 +6313,24 @@ void ieee80211_iterate_stations_atomic(struct ieee80211_hw *hw,
void (*iterator)(void *data,
struct ieee80211_sta *sta),
void *data);
+
+/**
+ * ieee80211_iterate_stations_mtx - iterate stations
+ *
+ * This function iterates over all stations associated with a given
+ * hardware that are currently uploaded to the driver and calls the callback
+ * function for them. This version can only be used while holding the wiphy
+ * mutex.
+ *
+ * @hw: the hardware struct of which the interfaces should be iterated over
+ * @iterator: the iterator function to call
+ * @data: first argument of the iterator function
+ */
+void ieee80211_iterate_stations_mtx(struct ieee80211_hw *hw,
+ void (*iterator)(void *data,
+ struct ieee80211_sta *sta),
+ void *data);
+
/**
* ieee80211_queue_work - add work onto the mac80211 workqueue
*
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index ef7133ac13f0..e12c871f0477 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -940,6 +940,23 @@ static void __iterate_stations(struct ieee80211_local *local,
}
}
+static void __iterate_stations_safe(struct ieee80211_local *local,
+ void (*iterator)(void *data,
+ struct ieee80211_sta *sta),
+ void *data)
+{
+ struct sta_info *sta, *sta_temp;
+
+ lockdep_assert_wiphy(local->hw.wiphy);
+
+ list_for_each_entry_safe(sta, sta_temp, &local->sta_list, list) {
+ if (!sta->uploaded)
+ continue;
+
+ iterator(data, &sta->sta);
+ }
+}
+
void ieee80211_iterate_stations_atomic(struct ieee80211_hw *hw,
void (*iterator)(void *data,
struct ieee80211_sta *sta),
@@ -953,6 +970,19 @@ void ieee80211_iterate_stations_atomic(struct ieee80211_hw *hw,
}
EXPORT_SYMBOL_GPL(ieee80211_iterate_stations_atomic);
+void ieee80211_iterate_stations_mtx(struct ieee80211_hw *hw,
+ void (*iterator)(void *data,
+ struct ieee80211_sta *sta),
+ void *data)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ lockdep_assert_wiphy(local->hw.wiphy);
+
+ __iterate_stations_safe(local, iterator, data);
+}
+EXPORT_SYMBOL_GPL(ieee80211_iterate_stations_mtx);
+
struct ieee80211_vif *wdev_to_ieee80211_vif(struct wireless_dev *wdev)
{
struct ieee80211_sub_if_data *sdata = IEEE80211_WDEV_TO_SUB_IF(wdev);
--
2.34.1
