Commit 4f6fab47 authored by Johannes Berg's avatar Johannes Berg Committed by John W. Linville
Browse files

mac80211: clean up sta_info_destroy() users wrt. RCU/locking 



Calling sta_info_destroy() doesn't require RCU-synchronisation
before-hand because it does that internally. However, it does
require rtnl-locking so insert that where necessary.

Also clean up the code doing it internally to be a bit clearer and
not synchronize twice if keys are configured.

Signed-off-by: default avatarJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: default avatarJohn W. Linville <linville@tuxdriver.com>
parent 93e5deb1

net/mac80211/cfg.c

+1 −5
Original line number Diff line number Diff line
@@ -700,11 +700,7 @@ static int ieee80211_del_station(struct wiphy *wiphy, struct net_device *dev, 
			return -ENOENT;



		sta_info_unlink(&sta);



		if (sta) {

			synchronize_rcu();

		sta_info_destroy(sta);

		}

	} else

		sta_info_flush(local, sdata);

net/mac80211/ieee80211_sta.c

+0 −1
Original line number Diff line number Diff line
@@ -939,7 +939,6 @@ static void ieee80211_associated(struct net_device *dev, 
	rcu_read_unlock();



	if (disassoc && sta) {

		synchronize_rcu();

		rtnl_lock();

		sta_info_destroy(sta);

		rtnl_unlock();

net/mac80211/sta_info.c

+19 −14
Original line number Diff line number Diff line
@@ -180,13 +180,22 @@ void sta_info_destroy(struct sta_info *sta) 
		mesh_plink_deactivate(sta);

#endif



	if (sta->key) {

		/*

		 * NOTE: This will call synchronize_rcu() internally to

		 * make sure no key references can be in use. We rely on

	 * that here for the mesh code!

		 * that when we take this branch to make sure nobody can

		 * reference this STA struct any longer!

		 */

		ieee80211_key_free(sta->key);

		WARN_ON(sta->key);

	} else {

		/*

		 * Make sure that nobody can reference this STA struct

		 * any longer.

		 */

		synchronize_rcu();

	}



#ifdef CONFIG_MAC80211_MESH

	if (ieee80211_vif_is_mesh(&sta->sdata->vif))
@@ -628,11 +637,9 @@ static void sta_info_debugfs_add_work(struct work_struct *work) 
		rate_control_add_sta_debugfs(sta);



		sta = __sta_info_unpin(sta);



		if (sta) {

			synchronize_rcu();

		rtnl_lock();

		sta_info_destroy(sta);

		}

		rtnl_unlock();

	}

}

#endif
@@ -694,8 +701,6 @@ int sta_info_flush(struct ieee80211_local *local, 
	}

	spin_unlock_irqrestore(&local->sta_lock, flags);



	synchronize_rcu();



	list_for_each_entry_safe(sta, tmp, &tmp_list, list)

		sta_info_destroy(sta);

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