6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rory Little <rory@xxxxxxxxxxxxxxx> [ Upstream commit 7c3b69eadea9e57c28bf914b0fd70f268f3682e1 ] 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> Link: https://patch.msgid.link/20240806004024.2014080-2-rory@xxxxxxxxxxxxxxx [unify internal list iteration functions] Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Stable-dep-of: 8fac3266c68a ("wifi: ath12k: fix atomic calls in ath12k_mac_op_set_bitrate_mask()") Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- include/net/mac80211.h | 18 ++++++++++++++++++ net/mac80211/util.c | 16 +++++++++++++++- 2 files changed, 33 insertions(+), 1 deletion(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 901fe3ac139e..835a58ce9ca5 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -6080,6 +6080,24 @@ 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 d682c32821a1..cc3c46a82077 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -827,7 +827,8 @@ static void __iterate_stations(struct ieee80211_local *local, { struct sta_info *sta; - list_for_each_entry_rcu(sta, &local->sta_list, list) { + list_for_each_entry_rcu(sta, &local->sta_list, list, + lockdep_is_held(&local->hw.wiphy->mtx)) { if (!sta->uploaded) continue; @@ -848,6 +849,19 @@ 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(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); -- 2.39.5