mac80211: annotate station rcu dereferences

The new RCU lockdep support warns about these
in some contexts -- make it aware of the locks
used to protect all this. Different locks are
used in different contexts which unfortunately
means we can't get perfect checking.

Also remove rcu_dereference() from two places
that don't actually dereference the pointers.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Johannes Berg 2010-04-06 11:18:42 +02:00 committed by John W. Linville
parent 1cb561f837
commit 0379185b6c
2 changed files with 18 additions and 6 deletions

View File

@ -225,11 +225,11 @@ void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP:
sdata->vif.bss_conf.enable_beacon =
!!rcu_dereference(sdata->u.ap.beacon);
!!sdata->u.ap.beacon;
break;
case NL80211_IFTYPE_ADHOC:
sdata->vif.bss_conf.enable_beacon =
!!rcu_dereference(sdata->u.ibss.presp);
!!sdata->u.ibss.presp;
break;
case NL80211_IFTYPE_MESH_POINT:
sdata->vif.bss_conf.enable_beacon = true;

View File

@ -93,12 +93,18 @@ struct sta_info *sta_info_get(struct ieee80211_sub_if_data *sdata,
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
sta = rcu_dereference(local->sta_hash[STA_HASH(addr)]);
sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
rcu_read_lock_held() ||
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
while (sta) {
if (sta->sdata == sdata &&
memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
break;
sta = rcu_dereference(sta->hnext);
sta = rcu_dereference_check(sta->hnext,
rcu_read_lock_held() ||
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
}
return sta;
}
@ -113,13 +119,19 @@ struct sta_info *sta_info_get_bss(struct ieee80211_sub_if_data *sdata,
struct ieee80211_local *local = sdata->local;
struct sta_info *sta;
sta = rcu_dereference(local->sta_hash[STA_HASH(addr)]);
sta = rcu_dereference_check(local->sta_hash[STA_HASH(addr)],
rcu_read_lock_held() ||
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
while (sta) {
if ((sta->sdata == sdata ||
sta->sdata->bss == sdata->bss) &&
memcmp(sta->sta.addr, addr, ETH_ALEN) == 0)
break;
sta = rcu_dereference(sta->hnext);
sta = rcu_dereference_check(sta->hnext,
rcu_read_lock_held() ||
lockdep_is_held(&local->sta_lock) ||
lockdep_is_held(&local->sta_mtx));
}
return sta;
}