diff options
| -rw-r--r-- | include/net/mac80211.h | 21 | ||||
| -rw-r--r-- | net/mac80211/driver-ops.h | 16 | ||||
| -rw-r--r-- | net/mac80211/sta_info.c | 2 | ||||
| -rw-r--r-- | net/mac80211/trace.h | 34 |
4 files changed, 52 insertions, 21 deletions
diff --git a/include/net/mac80211.h b/include/net/mac80211.h index c014acc0..22b6dd9 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -2495,7 +2495,11 @@ enum ieee80211_roc_type { * AP, IBSS/WDS/mesh peer etc. This callback can sleep. * * @sta_remove: Notifies low level driver about removal of an associated - * station, AP, IBSS/WDS/mesh peer etc. This callback can sleep. + * station, AP, IBSS/WDS/mesh peer etc. Note that after the callback + * returns it isn't safe to use the pointer, not even RCU protected; + * no RCU grace period is guaranteed between returning here and freeing + * the station. See @sta_pre_rcu_remove if needed. + * This callback can sleep. * * @sta_add_debugfs: Drivers can use this callback to add debugfs files * when a station is added to mac80211's station list. This callback @@ -2514,7 +2518,17 @@ enum ieee80211_roc_type { * station (which can be the AP, a client, IBSS/WDS/mesh peer etc.) * This callback is mutually exclusive with @sta_add/@sta_remove. * It must not fail for down transitions but may fail for transitions - * up the list of states. + * up the list of states. Also note that after the callback returns it + * isn't safe to use the pointer, not even RCU protected - no RCU grace + * period is guaranteed between returning here and freeing the station. + * See @sta_pre_rcu_remove if needed. + * The callback can sleep. + * + * @sta_pre_rcu_remove: Notify driver about station removal before RCU + * synchronisation. This is useful if a driver needs to have station + * pointers protected using RCU, it can then use this call to clear + * the pointers instead of waiting for an RCU grace period to elapse + * in @sta_state. * The callback can sleep. * * @sta_rc_update: Notifies the driver of changes to the bitrates that can be @@ -2827,6 +2841,9 @@ struct ieee80211_ops { struct ieee80211_sta *sta, enum ieee80211_sta_state old_state, enum ieee80211_sta_state new_state); + void (*sta_pre_rcu_remove)(struct ieee80211_hw *hw, + struct ieee80211_vif *vif, + struct ieee80211_sta *sta); void (*sta_rc_update)(struct ieee80211_hw *hw, struct ieee80211_vif *vif, struct ieee80211_sta *sta, diff --git a/net/mac80211/driver-ops.h b/net/mac80211/driver-ops.h index f98059a..ef8b385 100644 --- a/net/mac80211/driver-ops.h +++ b/net/mac80211/driver-ops.h @@ -534,6 +534,22 @@ static inline void drv_sta_remove_debugfs(struct ieee80211_local *local, } #endif +static inline void drv_sta_pre_rcu_remove(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata, + struct sta_info *sta) +{ + might_sleep(); + + sdata = get_bss_sdata(sdata); + check_sdata_in_driver(sdata); + + trace_drv_sta_pre_rcu_remove(local, sdata, &sta->sta); + if (local->ops->sta_pre_rcu_remove) + local->ops->sta_pre_rcu_remove(&local->hw, &sdata->vif, + &sta->sta); + trace_drv_return_void(local); +} + static inline __must_check int drv_sta_state(struct ieee80211_local *local, struct ieee80211_sub_if_data *sdata, diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c index 8ae37f6..1e14774 100644 --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -873,6 +873,8 @@ int __must_check __sta_info_destroy(struct sta_info *sta) list_del_rcu(&sta->list); + drv_sta_pre_rcu_remove(local, sta->sdata, sta); + /* this always calls synchronize_net() */ ieee80211_free_sta_keys(local, sta); diff --git a/net/mac80211/trace.h b/net/mac80211/trace.h index 854bc59..3a669d7 100644 --- a/net/mac80211/trace.h +++ b/net/mac80211/trace.h @@ -766,7 +766,7 @@ TRACE_EVENT(drv_sta_rc_update, ) ); -TRACE_EVENT(drv_sta_add, +DECLARE_EVENT_CLASS(sta_event, TP_PROTO(struct ieee80211_local *local, struct ieee80211_sub_if_data *sdata, struct ieee80211_sta *sta), @@ -791,29 +791,25 @@ TRACE_EVENT(drv_sta_add, ) ); -TRACE_EVENT(drv_sta_remove, +DEFINE_EVENT(sta_event, drv_sta_add, TP_PROTO(struct ieee80211_local *local, struct ieee80211_sub_if_data *sdata, struct ieee80211_sta *sta), + TP_ARGS(local, sdata, sta) +); - TP_ARGS(local, sdata, sta), - - TP_STRUCT__entry( - LOCAL_ENTRY - VIF_ENTRY - STA_ENTRY - ), - - TP_fast_assign( - LOCAL_ASSIGN; - VIF_ASSIGN; - STA_ASSIGN; - ), +DEFINE_EVENT(sta_event, drv_sta_remove, + TP_PROTO(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata, + struct ieee80211_sta *sta), + TP_ARGS(local, sdata, sta) +); - TP_printk( - LOCAL_PR_FMT VIF_PR_FMT STA_PR_FMT, - LOCAL_PR_ARG, VIF_PR_ARG, STA_PR_ARG - ) +DEFINE_EVENT(sta_event, drv_sta_pre_rcu_remove, + TP_PROTO(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata, + struct ieee80211_sta *sta), + TP_ARGS(local, sdata, sta) ); TRACE_EVENT(drv_conf_tx, |
