diff options
Diffstat (limited to 'net/mac80211/offchannel.c')
| -rw-r--r-- | net/mac80211/offchannel.c | 299 |
1 files changed, 299 insertions, 0 deletions
diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c new file mode 100644 index 00000000..c55eb9d8 --- /dev/null +++ b/net/mac80211/offchannel.c @@ -0,0 +1,299 @@ +/* + * Off-channel operation helpers + * + * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi> + * Copyright 2004, Instant802 Networks, Inc. + * Copyright 2005, Devicescape Software, Inc. + * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz> + * Copyright 2007, Michael Wu <flamingice@sourmilk.net> + * Copyright 2009 Johannes Berg <johannes@sipsolutions.net> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <net/mac80211.h> +#include "ieee80211_i.h" +#include "driver-trace.h" + +/* + * Tell our hardware to disable PS. + * Optionally inform AP that we will go to sleep so that it will buffer + * the frames while we are doing off-channel work. This is optional + * because we *may* be doing work on-operating channel, and want our + * hardware unconditionally awake, but still let the AP send us normal frames. + */ +static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata, + bool tell_ap) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_if_managed *ifmgd = &sdata->u.mgd; + + local->offchannel_ps_enabled = false; + + /* FIXME: what to do when local->pspolling is true? */ + + del_timer_sync(&local->dynamic_ps_timer); + del_timer_sync(&ifmgd->bcn_mon_timer); + del_timer_sync(&ifmgd->conn_mon_timer); + + cancel_work_sync(&local->dynamic_ps_enable_work); + + if (local->hw.conf.flags & IEEE80211_CONF_PS) { + local->offchannel_ps_enabled = true; + local->hw.conf.flags &= ~IEEE80211_CONF_PS; + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); + } + + if (tell_ap && (!local->offchannel_ps_enabled || + !(local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK))) + /* + * If power save was enabled, no need to send a nullfunc + * frame because AP knows that we are sleeping. But if the + * hardware is creating the nullfunc frame for power save + * status (ie. IEEE80211_HW_PS_NULLFUNC_STACK is not + * enabled) and power save was enabled, the firmware just + * sent a null frame with power save disabled. So we need + * to send a new nullfunc frame to inform the AP that we + * are again sleeping. + */ + ieee80211_send_nullfunc(local, sdata, 1); +} + +/* inform AP that we are awake again, unless power save is enabled */ +static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + + if (!local->ps_sdata) + ieee80211_send_nullfunc(local, sdata, 0); + else if (local->offchannel_ps_enabled) { + /* + * In !IEEE80211_HW_PS_NULLFUNC_STACK case the hardware + * will send a nullfunc frame with the powersave bit set + * even though the AP already knows that we are sleeping. + * This could be avoided by sending a null frame with power + * save bit disabled before enabling the power save, but + * this doesn't gain anything. + * + * When IEEE80211_HW_PS_NULLFUNC_STACK is enabled, no need + * to send a nullfunc frame because AP already knows that + * we are sleeping, let's just enable power save mode in + * hardware. + */ + /* TODO: Only set hardware if CONF_PS changed? + * TODO: Should we set offchannel_ps_enabled to false? + */ + local->hw.conf.flags |= IEEE80211_CONF_PS; + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS); + } else if (local->hw.conf.dynamic_ps_timeout > 0) { + /* + * If IEEE80211_CONF_PS was not set and the dynamic_ps_timer + * had been running before leaving the operating channel, + * restart the timer now and send a nullfunc frame to inform + * the AP that we are awake. + */ + ieee80211_send_nullfunc(local, sdata, 0); + mod_timer(&local->dynamic_ps_timer, jiffies + + msecs_to_jiffies(local->hw.conf.dynamic_ps_timeout)); + } + + ieee80211_sta_reset_beacon_monitor(sdata); + ieee80211_sta_reset_conn_monitor(sdata); +} + +void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local, + bool offchannel_ps_enable) +{ + struct ieee80211_sub_if_data *sdata; + + /* + * notify the AP about us leaving the channel and stop all + * STA interfaces. + */ + mutex_lock(&local->iflist_mtx); + list_for_each_entry(sdata, &local->interfaces, list) { + if (!ieee80211_sdata_running(sdata)) + continue; + + if (sdata->vif.type != NL80211_IFTYPE_MONITOR) + set_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); + + /* Check to see if we should disable beaconing. */ + if (sdata->vif.type == NL80211_IFTYPE_AP || + sdata->vif.type == NL80211_IFTYPE_ADHOC || + sdata->vif.type == NL80211_IFTYPE_MESH_POINT) + ieee80211_bss_info_change_notify( + sdata, BSS_CHANGED_BEACON_ENABLED); + + if (sdata->vif.type != NL80211_IFTYPE_MONITOR) { + netif_tx_stop_all_queues(sdata->dev); + if (offchannel_ps_enable && + (sdata->vif.type == NL80211_IFTYPE_STATION) && + sdata->u.mgd.associated) + ieee80211_offchannel_ps_enable(sdata, true); + } + } + mutex_unlock(&local->iflist_mtx); +} + +void ieee80211_offchannel_enable_all_ps(struct ieee80211_local *local, + bool tell_ap) +{ + struct ieee80211_sub_if_data *sdata; + + mutex_lock(&local->iflist_mtx); + list_for_each_entry(sdata, &local->interfaces, list) { + if (!ieee80211_sdata_running(sdata)) + continue; + + if (sdata->vif.type == NL80211_IFTYPE_STATION && + sdata->u.mgd.associated) + ieee80211_offchannel_ps_enable(sdata, tell_ap); + } + mutex_unlock(&local->iflist_mtx); +} + +void ieee80211_offchannel_return(struct ieee80211_local *local, + bool enable_beaconing, + bool offchannel_ps_disable) +{ + struct ieee80211_sub_if_data *sdata; + + mutex_lock(&local->iflist_mtx); + list_for_each_entry(sdata, &local->interfaces, list) { + if (!ieee80211_sdata_running(sdata)) + continue; + + /* Tell AP we're back */ + if (offchannel_ps_disable && + sdata->vif.type == NL80211_IFTYPE_STATION) { + if (sdata->u.mgd.associated) + ieee80211_offchannel_ps_disable(sdata); + } + + if (sdata->vif.type != NL80211_IFTYPE_MONITOR) { + clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state); + /* + * This may wake up queues even though the driver + * currently has them stopped. This is not very + * likely, since the driver won't have gotten any + * (or hardly any) new packets while we weren't + * on the right channel, and even if it happens + * it will at most lead to queueing up one more + * packet per queue in mac80211 rather than on + * the interface qdisc. + */ + netif_tx_wake_all_queues(sdata->dev); + } + + /* Check to see if we should re-enable beaconing */ + if (enable_beaconing && + (sdata->vif.type == NL80211_IFTYPE_AP || + sdata->vif.type == NL80211_IFTYPE_ADHOC || + sdata->vif.type == NL80211_IFTYPE_MESH_POINT)) + ieee80211_bss_info_change_notify( + sdata, BSS_CHANGED_BEACON_ENABLED); + } + mutex_unlock(&local->iflist_mtx); +} + +static void ieee80211_hw_roc_start(struct work_struct *work) +{ + struct ieee80211_local *local = + container_of(work, struct ieee80211_local, hw_roc_start); + struct ieee80211_sub_if_data *sdata; + + mutex_lock(&local->mtx); + + if (!local->hw_roc_channel) { + mutex_unlock(&local->mtx); + return; + } + + ieee80211_recalc_idle(local); + + if (local->hw_roc_skb) { + sdata = IEEE80211_DEV_TO_SUB_IF(local->hw_roc_dev); + ieee80211_tx_skb(sdata, local->hw_roc_skb); + local->hw_roc_skb = NULL; + } else { + cfg80211_ready_on_channel(local->hw_roc_dev, + local->hw_roc_cookie, + local->hw_roc_channel, + local->hw_roc_channel_type, + local->hw_roc_duration, + GFP_KERNEL); + } + + mutex_unlock(&local->mtx); +} + +void ieee80211_ready_on_channel(struct ieee80211_hw *hw) +{ + struct ieee80211_local *local = hw_to_local(hw); + + trace_api_ready_on_channel(local); + + ieee80211_queue_work(hw, &local->hw_roc_start); +} +EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel); + +static void ieee80211_hw_roc_done(struct work_struct *work) +{ + struct ieee80211_local *local = + container_of(work, struct ieee80211_local, hw_roc_done); + + mutex_lock(&local->mtx); + + if (!local->hw_roc_channel) { + mutex_unlock(&local->mtx); + return; + } + + /* was never transmitted */ + if (local->hw_roc_skb) { + u64 cookie; + + cookie = local->hw_roc_cookie ^ 2; + + cfg80211_mgmt_tx_status(local->hw_roc_dev, cookie, + local->hw_roc_skb->data, + local->hw_roc_skb->len, false, + GFP_KERNEL); + + kfree_skb(local->hw_roc_skb); + local->hw_roc_skb = NULL; + local->hw_roc_skb_for_status = NULL; + } + + if (!local->hw_roc_for_tx) + cfg80211_remain_on_channel_expired(local->hw_roc_dev, + local->hw_roc_cookie, + local->hw_roc_channel, + local->hw_roc_channel_type, + GFP_KERNEL); + + local->hw_roc_channel = NULL; + local->hw_roc_cookie = 0; + + ieee80211_recalc_idle(local); + + mutex_unlock(&local->mtx); +} + +void ieee80211_remain_on_channel_expired(struct ieee80211_hw *hw) +{ + struct ieee80211_local *local = hw_to_local(hw); + + trace_api_remain_on_channel_expired(local); + + ieee80211_queue_work(hw, &local->hw_roc_done); +} +EXPORT_SYMBOL_GPL(ieee80211_remain_on_channel_expired); + +void ieee80211_hw_roc_setup(struct ieee80211_local *local) +{ + INIT_WORK(&local->hw_roc_start, ieee80211_hw_roc_start); + INIT_WORK(&local->hw_roc_done, ieee80211_hw_roc_done); +} |