From 4f6fab472c4c7c21d577f85fabec7628d4a05637 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Mon, 31 Mar 2008 19:23:02 +0200 Subject: [PATCH] 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: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/cfg.c | 6 +----- net/mac80211/ieee80211_sta.c | 1 - net/mac80211/sta_info.c | 33 +++++++++++++++++++-------------- 3 files changed, 20 insertions(+), 20 deletions(-) diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index fbd462c78e18..5f8db5cab65d 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -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); - } + sta_info_destroy(sta); } else sta_info_flush(local, sdata); diff --git a/net/mac80211/ieee80211_sta.c b/net/mac80211/ieee80211_sta.c index 00fde111c268..c5a47f8d873a 100644 --- a/net/mac80211/ieee80211_sta.c +++ b/net/mac80211/ieee80211_sta.c @@ -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(); diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 5497ca1843fe..dfca96e05d69 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -180,13 +180,22 @@ void sta_info_destroy(struct sta_info *sta) mesh_plink_deactivate(sta); #endif - /* - * 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! - */ - ieee80211_key_free(sta->key); - WARN_ON(sta->key); + if (sta->key) { + /* + * NOTE: This will call synchronize_rcu() internally to + * make sure no key references can be in use. We rely on + * 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(); - sta_info_destroy(sta); - } + 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); -- 2.20.1