--- /dev/null
+/*
+ * 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 <linux/export.h>
+#include <net/mac80211.h>
+#include "ieee80211_i.h"
+#include "driver-ops.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)
+{
+ 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 (!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)
+{
+ struct ieee80211_sub_if_data *sdata;
+
+ if (WARN_ON(local->use_chanctx))
+ return;
+
+ /*
+ * notify the AP about us leaving the channel and stop all
+ * STA interfaces.
+ */
+
+ /*
+ * Stop queues and transmit all frames queued by the driver
+ * before sending nullfunc to enable powersave at the AP.
+ */
+ ieee80211_stop_queues_by_reason(&local->hw, IEEE80211_MAX_QUEUE_MAP,
+ IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL,
+ false);
+ ieee80211_flush_queues(local, NULL, false);
+
+ 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_P2P_DEVICE)
+ 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.bss_conf.enable_beacon) {
+ set_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
+ &sdata->state);
+ sdata->vif.bss_conf.enable_beacon = false;
+ ieee80211_bss_info_change_notify(
+ sdata, BSS_CHANGED_BEACON_ENABLED);
+ }
+
+ if (sdata->vif.type == NL80211_IFTYPE_STATION &&
+ sdata->u.mgd.associated)
+ ieee80211_offchannel_ps_enable(sdata);
+ }
+ mutex_unlock(&local->iflist_mtx);
+}
+
+void ieee80211_offchannel_return(struct ieee80211_local *local)
+{
+ struct ieee80211_sub_if_data *sdata;
+
+ if (WARN_ON(local->use_chanctx))
+ return;
+
+ mutex_lock(&local->iflist_mtx);
+ list_for_each_entry(sdata, &local->interfaces, list) {
+ if (sdata->vif.type == NL80211_IFTYPE_P2P_DEVICE)
+ continue;
+
+ if (sdata->vif.type != NL80211_IFTYPE_MONITOR)
+ clear_bit(SDATA_STATE_OFFCHANNEL, &sdata->state);
+
+ if (!ieee80211_sdata_running(sdata))
+ continue;
+
+ /* Tell AP we're back */
+ if (sdata->vif.type == NL80211_IFTYPE_STATION &&
+ sdata->u.mgd.associated)
+ ieee80211_offchannel_ps_disable(sdata);
+
+ if (test_and_clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED,
+ &sdata->state)) {
+ sdata->vif.bss_conf.enable_beacon = true;
+ ieee80211_bss_info_change_notify(
+ sdata, BSS_CHANGED_BEACON_ENABLED);
+ }
+ }
+ mutex_unlock(&local->iflist_mtx);
+
+ ieee80211_wake_queues_by_reason(&local->hw, IEEE80211_MAX_QUEUE_MAP,
+ IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL,
+ false);
+}
+
+void ieee80211_handle_roc_started(struct ieee80211_roc_work *roc)
+{
+ if (roc->notified)
+ return;
+
+ if (roc->mgmt_tx_cookie) {
+ if (!WARN_ON(!roc->frame)) {
+ ieee80211_tx_skb_tid_band(roc->sdata, roc->frame, 7,
+ roc->chan->band);
+ roc->frame = NULL;
+ }
+ } else {
+ cfg80211_ready_on_channel(&roc->sdata->wdev, roc->cookie,
+ roc->chan, roc->req_duration,
+ GFP_KERNEL);
+ }
+
+ roc->notified = true;
+}
+
+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_roc_work *roc, *dep, *tmp;
+
+ mutex_lock(&local->mtx);
+
+ if (list_empty(&local->roc_list))
+ goto out_unlock;
+
+ roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
+ list);
+
+ if (!roc->started)
+ goto out_unlock;
+
+ roc->hw_begun = true;
+ roc->hw_start_time = local->hw_roc_start_time;
+
+ ieee80211_handle_roc_started(roc);
+ list_for_each_entry_safe(dep, tmp, &roc->dependents, list) {
+ ieee80211_handle_roc_started(dep);
+
+ if (dep->duration > roc->duration) {
+ u32 dur = dep->duration;
+ dep->duration = dur - roc->duration;
+ roc->duration = dur;
+ list_move(&dep->list, &roc->list);
+ }
+ }
+ out_unlock:
+ mutex_unlock(&local->mtx);
+}
+
+void ieee80211_ready_on_channel(struct ieee80211_hw *hw)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+
+ local->hw_roc_start_time = jiffies;
+
+ trace_api_ready_on_channel(local);
+
+ ieee80211_queue_work(hw, &local->hw_roc_start);
+}
+EXPORT_SYMBOL_GPL(ieee80211_ready_on_channel);
+
+void ieee80211_start_next_roc(struct ieee80211_local *local)
+{
+ struct ieee80211_roc_work *roc;
+
+ lockdep_assert_held(&local->mtx);
+
+ if (list_empty(&local->roc_list)) {
+ ieee80211_run_deferred_scan(local);
+ return;
+ }
+
+ roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
+ list);
+
+ if (WARN_ON_ONCE(roc->started))
+ return;
+
+ if (local->ops->remain_on_channel) {
+ int ret, duration = roc->duration;
+
+ /* XXX: duplicated, see ieee80211_start_roc_work() */
+ if (!duration)
+ duration = 10;
+
+ ret = drv_remain_on_channel(local, roc->sdata, roc->chan,
+ duration, roc->type);
+
+ roc->started = true;
+
+ if (ret) {
+ wiphy_warn(local->hw.wiphy,
+ "failed to start next HW ROC (%d)\n", ret);
+ /*
+ * queue the work struct again to avoid recursion
+ * when multiple failures occur
+ */
+ ieee80211_remain_on_channel_expired(&local->hw);
+ }
+ } else {
+ /* delay it a bit */
+ ieee80211_queue_delayed_work(&local->hw, &roc->work,
+ round_jiffies_relative(HZ/2));
+ }
+}
+
+void ieee80211_roc_notify_destroy(struct ieee80211_roc_work *roc, bool free)
+{
+ struct ieee80211_roc_work *dep, *tmp;
+
+ if (WARN_ON(roc->to_be_freed))
+ return;
+
+ /* was never transmitted */
+ if (roc->frame) {
+ cfg80211_mgmt_tx_status(&roc->sdata->wdev,
+ (unsigned long)roc->frame,
+ roc->frame->data, roc->frame->len,
+ false, GFP_KERNEL);
+ kfree_skb(roc->frame);
+ }
+
+ if (!roc->mgmt_tx_cookie)
+ cfg80211_remain_on_channel_expired(&roc->sdata->wdev,
+ roc->cookie, roc->chan,
+ GFP_KERNEL);
+
+ list_for_each_entry_safe(dep, tmp, &roc->dependents, list)
+ ieee80211_roc_notify_destroy(dep, true);
+
+ if (free)
+ kfree(roc);
+ else
+ roc->to_be_freed = true;
+}
+
+void ieee80211_sw_roc_work(struct work_struct *work)
+{
+ struct ieee80211_roc_work *roc =
+ container_of(work, struct ieee80211_roc_work, work.work);
+ struct ieee80211_sub_if_data *sdata = roc->sdata;
+ struct ieee80211_local *local = sdata->local;
+ bool started, on_channel;
+
+ mutex_lock(&local->mtx);
+
+ if (roc->to_be_freed)
+ goto out_unlock;
+
+ if (roc->abort)
+ goto finish;
+
+ if (WARN_ON(list_empty(&local->roc_list)))
+ goto out_unlock;
+
+ if (WARN_ON(roc != list_first_entry(&local->roc_list,
+ struct ieee80211_roc_work,
+ list)))
+ goto out_unlock;
+
+ if (!roc->started) {
+ struct ieee80211_roc_work *dep;
+
+ WARN_ON(local->use_chanctx);
+
+ /* If actually operating on the desired channel (with at least
+ * 20 MHz channel width) don't stop all the operations but still
+ * treat it as though the ROC operation started properly, so
+ * other ROC operations won't interfere with this one.
+ */
+ roc->on_channel = roc->chan == local->_oper_chandef.chan &&
+ local->_oper_chandef.width != NL80211_CHAN_WIDTH_5 &&
+ local->_oper_chandef.width != NL80211_CHAN_WIDTH_10;
+
+ /* start this ROC */
+ ieee80211_recalc_idle(local);
+
+ if (!roc->on_channel) {
+ ieee80211_offchannel_stop_vifs(local);
+
+ local->tmp_channel = roc->chan;
+ ieee80211_hw_config(local, 0);
+ }
+
+ /* tell userspace or send frame */
+ ieee80211_handle_roc_started(roc);
+ list_for_each_entry(dep, &roc->dependents, list)
+ ieee80211_handle_roc_started(dep);
+
+ /* if it was pure TX, just finish right away */
+ if (!roc->duration)
+ goto finish;
+
+ roc->started = true;
+ ieee80211_queue_delayed_work(&local->hw, &roc->work,
+ msecs_to_jiffies(roc->duration));
+ } else {
+ /* finish this ROC */
+ finish:
+ list_del(&roc->list);
+ started = roc->started;
+ on_channel = roc->on_channel;
+ ieee80211_roc_notify_destroy(roc, !roc->abort);
+
+ if (started && !on_channel) {
+ ieee80211_flush_queues(local, NULL, false);
+
+ local->tmp_channel = NULL;
+ ieee80211_hw_config(local, 0);
+
+ ieee80211_offchannel_return(local);
+ }
+
+ ieee80211_recalc_idle(local);
+
+ if (started)
+ ieee80211_start_next_roc(local);
+ else if (list_empty(&local->roc_list))
+ ieee80211_run_deferred_scan(local);
+ }
+
+ out_unlock:
+ mutex_unlock(&local->mtx);
+}
+
+static void ieee80211_hw_roc_done(struct work_struct *work)
+{
+ struct ieee80211_local *local =
+ container_of(work, struct ieee80211_local, hw_roc_done);
+ struct ieee80211_roc_work *roc;
+
+ mutex_lock(&local->mtx);
+
+ if (list_empty(&local->roc_list))
+ goto out_unlock;
+
+ roc = list_first_entry(&local->roc_list, struct ieee80211_roc_work,
+ list);
+
+ if (!roc->started)
+ goto out_unlock;
+
+ list_del(&roc->list);
+
+ ieee80211_roc_notify_destroy(roc, true);
+
+ /* if there's another roc, start it now */
+ ieee80211_start_next_roc(local);
+
+ out_unlock:
+ 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_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);
+ INIT_LIST_HEAD(&local->roc_list);
+}
+
+void ieee80211_roc_purge(struct ieee80211_local *local,
+ struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_roc_work *roc, *tmp;
+ LIST_HEAD(tmp_list);
+
+ mutex_lock(&local->mtx);
+ list_for_each_entry_safe(roc, tmp, &local->roc_list, list) {
+ if (sdata && roc->sdata != sdata)
+ continue;
+
+ if (roc->started && local->ops->remain_on_channel) {
+ /* can race, so ignore return value */
+ drv_cancel_remain_on_channel(local);
+ }
+
+ list_move_tail(&roc->list, &tmp_list);
+ roc->abort = true;
+ }
+ mutex_unlock(&local->mtx);
+
+ list_for_each_entry_safe(roc, tmp, &tmp_list, list) {
+ if (local->ops->remain_on_channel) {
+ list_del(&roc->list);
+ ieee80211_roc_notify_destroy(roc, true);
+ } else {
+ ieee80211_queue_delayed_work(&local->hw, &roc->work, 0);
+
+ /* work will clean up etc */
+ flush_delayed_work(&roc->work);
+ WARN_ON(!roc->to_be_freed);
+ kfree(roc);
+ }
+ }
+
+ WARN_ON_ONCE(!list_empty(&tmp_list));
+}
Code Review / kvmfornfv.git / blobdiff