/*

   * Interface handling (except master interface)
   *

   * Copyright 2002-2005, Instant802 Networks, Inc.
   * Copyright 2005-2006, Devicescape Software, Inc.
   * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>

   * Copyright 2008, 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/kernel.h>
  #include <linux/if_arp.h>
  #include <linux/netdevice.h>
  #include <linux/rtnetlink.h>
  #include <net/mac80211.h>
  #include "ieee80211_i.h"
  #include "sta_info.h"

  #include "debugfs_netdev.h"

  #include "mesh.h"

  #include "led.h"

  #include "driver-ops.h"

  /**
   * DOC: Interface list locking
   *
   * The interface list in each struct ieee80211_local is protected
   * three-fold:
   *
   * (1) modifications may only be done under the RTNL
   * (2) modifications and readers are protected against each other by
   *     the iflist_mtx.
   * (3) modifications are done in an RCU manner so atomic readers
   *     can traverse the list in RCU-safe blocks.
   *
   * As a consequence, reads (traversals) of the list can be protected
   * by either the RTNL, the iflist_mtx or RCU.
   */

  static int ieee80211_change_mtu(struct net_device *dev, int new_mtu)
  {
  	int meshhdrlen;
  	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  
  	meshhdrlen = (sdata->vif.type == NL80211_IFTYPE_MESH_POINT) ? 5 : 0;
  
  	/* FIX: what would be proper limits for MTU?
  	 * This interface uses 802.3 frames. */
  	if (new_mtu < 256 ||
  	    new_mtu > IEEE80211_MAX_DATA_LEN - 24 - 6 - meshhdrlen) {
  		return -EINVAL;
  	}
  
  #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  	printk(KERN_DEBUG "%s: setting MTU %d
  ", dev->name, new_mtu);
  #endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
  	dev->mtu = new_mtu;
  	return 0;
  }
  
  static inline int identical_mac_addr_allowed(int type1, int type2)
  {
  	return type1 == NL80211_IFTYPE_MONITOR ||
  		type2 == NL80211_IFTYPE_MONITOR ||
  		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_WDS) ||
  		(type1 == NL80211_IFTYPE_WDS &&
  			(type2 == NL80211_IFTYPE_WDS ||
  			 type2 == NL80211_IFTYPE_AP)) ||
  		(type1 == NL80211_IFTYPE_AP && type2 == NL80211_IFTYPE_AP_VLAN) ||
  		(type1 == NL80211_IFTYPE_AP_VLAN &&
  			(type2 == NL80211_IFTYPE_AP ||
  			 type2 == NL80211_IFTYPE_AP_VLAN));
  }
  
  static int ieee80211_open(struct net_device *dev)
  {

  	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  	struct ieee80211_sub_if_data *nsdata;
  	struct ieee80211_local *local = sdata->local;

  	struct sta_info *sta;
  	struct ieee80211_if_init_conf conf;
  	u32 changed = 0;
  	int res;

  	u32 hw_reconf_flags = 0;

  	u8 null_addr[ETH_ALEN] = {0};

  	/* fail early if user set an invalid address */
  	if (compare_ether_addr(dev->dev_addr, null_addr) &&
  	    !is_valid_ether_addr(dev->dev_addr))
  		return -EADDRNOTAVAIL;
  
  	/* we hold the RTNL here so can safely walk the list */
  	list_for_each_entry(nsdata, &local->interfaces, list) {
  		struct net_device *ndev = nsdata->dev;
  
  		if (ndev != dev && netif_running(ndev)) {
  			/*
  			 * Allow only a single IBSS interface to be up at any
  			 * time. This is restricted because beacon distribution
  			 * cannot work properly if both are in the same IBSS.
  			 *
  			 * To remove this restriction we'd have to disallow them
  			 * from setting the same SSID on different IBSS interfaces
  			 * belonging to the same hardware. Then, however, we're
  			 * faced with having to adopt two different TSF timers...
  			 */
  			if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
  			    nsdata->vif.type == NL80211_IFTYPE_ADHOC)
  				return -EBUSY;
  
  			/*
  			 * The remaining checks are only performed for interfaces
  			 * with the same MAC address.
  			 */
  			if (compare_ether_addr(dev->dev_addr, ndev->dev_addr))
  				continue;
  
  			/*
  			 * check whether it may have the same address
  			 */
  			if (!identical_mac_addr_allowed(sdata->vif.type,
  							nsdata->vif.type))
  				return -ENOTUNIQ;
  
  			/*
  			 * can only add VLANs to enabled APs
  			 */
  			if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN &&
  			    nsdata->vif.type == NL80211_IFTYPE_AP)
  				sdata->bss = &nsdata->u.ap;
  		}
  	}
  
  	switch (sdata->vif.type) {
  	case NL80211_IFTYPE_WDS:
  		if (!is_valid_ether_addr(sdata->u.wds.remote_addr))
  			return -ENOLINK;
  		break;
  	case NL80211_IFTYPE_AP_VLAN:
  		if (!sdata->bss)
  			return -ENOLINK;
  		list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
  		break;
  	case NL80211_IFTYPE_AP:
  		sdata->bss = &sdata->u.ap;
  		break;
  	case NL80211_IFTYPE_MESH_POINT:
  		if (!ieee80211_vif_is_mesh(&sdata->vif))
  			break;
  		/* mesh ifaces must set allmulti to forward mcast traffic */
  		atomic_inc(&local->iff_allmultis);
  		break;
  	case NL80211_IFTYPE_STATION:
  	case NL80211_IFTYPE_MONITOR:
  	case NL80211_IFTYPE_ADHOC:
  		/* no special treatment */
  		break;
  	case NL80211_IFTYPE_UNSPECIFIED:
  	case __NL80211_IFTYPE_AFTER_LAST:
  		/* cannot happen */
  		WARN_ON(1);
  		break;
  	}
  
  	if (local->open_count == 0) {

  		res = drv_start(local);

  		if (res)
  			goto err_del_bss;

  		/* we're brought up, everything changes */
  		hw_reconf_flags = ~0;

  		ieee80211_led_radio(local, true);

  	}
  
  	/*
  	 * Check all interfaces and copy the hopefully now-present
  	 * MAC address to those that have the special null one.
  	 */
  	list_for_each_entry(nsdata, &local->interfaces, list) {
  		struct net_device *ndev = nsdata->dev;
  
  		/*
  		 * No need to check netif_running since we do not allow
  		 * it to start up with this invalid address.
  		 */
  		if (compare_ether_addr(null_addr, ndev->dev_addr) == 0)
  			memcpy(ndev->dev_addr,
  			       local->hw.wiphy->perm_addr,
  			       ETH_ALEN);
  	}
  
  	if (compare_ether_addr(null_addr, local->mdev->dev_addr) == 0)
  		memcpy(local->mdev->dev_addr, local->hw.wiphy->perm_addr,
  		       ETH_ALEN);
  
  	/*
  	 * Validate the MAC address for this device.
  	 */
  	if (!is_valid_ether_addr(dev->dev_addr)) {

  		if (!local->open_count)
  			drv_stop(local);

  		return -EADDRNOTAVAIL;
  	}
  
  	switch (sdata->vif.type) {
  	case NL80211_IFTYPE_AP_VLAN:
  		/* no need to tell driver */
  		break;
  	case NL80211_IFTYPE_MONITOR:
  		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
  			local->cooked_mntrs++;
  			break;
  		}
  
  		/* must be before the call to ieee80211_configure_filter */
  		local->monitors++;

  		if (local->monitors == 1) {

  			local->hw.conf.flags |= IEEE80211_CONF_RADIOTAP;

  			hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
  		}

  
  		if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
  			local->fif_fcsfail++;
  		if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
  			local->fif_plcpfail++;
  		if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
  			local->fif_control++;
  		if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
  			local->fif_other_bss++;
  
  		netif_addr_lock_bh(local->mdev);
  		ieee80211_configure_filter(local);
  		netif_addr_unlock_bh(local->mdev);
  		break;
  	case NL80211_IFTYPE_STATION:

  		sdata->u.mgd.flags &= ~IEEE80211_STA_PREV_BSSID_SET;

  		/* fall through */
  	default:
  		conf.vif = &sdata->vif;
  		conf.type = sdata->vif.type;
  		conf.mac_addr = dev->dev_addr;

  		res = drv_add_interface(local, &conf);

  		if (res)
  			goto err_stop;

  		if (ieee80211_vif_is_mesh(&sdata->vif)) {
  			local->fif_other_bss++;
  			netif_addr_lock_bh(local->mdev);
  			ieee80211_configure_filter(local);
  			netif_addr_unlock_bh(local->mdev);

  			ieee80211_start_mesh(sdata);

  		}

  		changed |= ieee80211_reset_erp_info(sdata);
  		ieee80211_bss_info_change_notify(sdata, changed);
  		ieee80211_enable_keys(sdata);

  		if (sdata->vif.type == NL80211_IFTYPE_STATION)

  			netif_carrier_off(dev);
  		else
  			netif_carrier_on(dev);
  	}
  
  	if (sdata->vif.type == NL80211_IFTYPE_WDS) {
  		/* Create STA entry for the WDS peer */
  		sta = sta_info_alloc(sdata, sdata->u.wds.remote_addr,
  				     GFP_KERNEL);
  		if (!sta) {
  			res = -ENOMEM;
  			goto err_del_interface;
  		}
  
  		/* no locking required since STA is not live yet */
  		sta->flags |= WLAN_STA_AUTHORIZED;
  
  		res = sta_info_insert(sta);
  		if (res) {
  			/* STA has been freed */
  			goto err_del_interface;
  		}
  	}
  
  	if (local->open_count == 0) {
  		res = dev_open(local->mdev);
  		WARN_ON(res);
  		if (res)
  			goto err_del_interface;
  		tasklet_enable(&local->tx_pending_tasklet);
  		tasklet_enable(&local->tasklet);
  	}
  
  	/*
  	 * set_multicast_list will be invoked by the networking core
  	 * which will check whether any increments here were done in
  	 * error and sync them down to the hardware as filter flags.
  	 */
  	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
  		atomic_inc(&local->iff_allmultis);
  
  	if (sdata->flags & IEEE80211_SDATA_PROMISC)
  		atomic_inc(&local->iff_promiscs);

  	hw_reconf_flags |= __ieee80211_recalc_idle(local);

  	local->open_count++;

  	if (hw_reconf_flags) {
  		ieee80211_hw_config(local, hw_reconf_flags);

  		/*
  		 * set default queue parameters so drivers don't
  		 * need to initialise the hardware if the hardware
  		 * doesn't start up with sane defaults
  		 */
  		ieee80211_set_wmm_default(sdata);
  	}

  	ieee80211_recalc_ps(local, -1);

  	/*
  	 * ieee80211_sta_work is disabled while network interface
  	 * is down. Therefore, some configuration changes may not
  	 * yet be effective. Trigger execution of ieee80211_sta_work
  	 * to fix this.
  	 */

  	if (sdata->vif.type == NL80211_IFTYPE_STATION)
  		queue_work(local->hw.workqueue, &sdata->u.mgd.work);

  	netif_tx_start_all_queues(dev);
  
  	return 0;
   err_del_interface:

  	drv_remove_interface(local, &conf);

   err_stop:

  	if (!local->open_count)
  		drv_stop(local);

   err_del_bss:
  	sdata->bss = NULL;
  	if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
  		list_del(&sdata->u.vlan.list);
  	return res;
  }
  
  static int ieee80211_stop(struct net_device *dev)
  {
  	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  	struct ieee80211_local *local = sdata->local;
  	struct ieee80211_if_init_conf conf;
  	struct sta_info *sta;

  	u32 hw_reconf_flags = 0;

  
  	/*
  	 * Stop TX on this interface first.
  	 */
  	netif_tx_stop_all_queues(dev);
  
  	/*
  	 * Now delete all active aggregation sessions.
  	 */
  	rcu_read_lock();
  
  	list_for_each_entry_rcu(sta, &local->sta_list, list) {
  		if (sta->sdata == sdata)

  			ieee80211_sta_tear_down_BA_sessions(sta);

  	}
  
  	rcu_read_unlock();
  
  	/*

  	 * Announce that we are leaving the network, in case we are a
  	 * station interface type. This must be done before removing
  	 * all stations associated with sta_info_flush, otherwise STA
  	 * information will be gone and no announce being done.
  	 */
  	if (sdata->vif.type == NL80211_IFTYPE_STATION) {
  		if (sdata->u.mgd.state != IEEE80211_STA_MLME_DISABLED)
  			ieee80211_sta_deauthenticate(sdata,
  				WLAN_REASON_DEAUTH_LEAVING);
  	}
  
  	/*

  	 * Remove all stations associated with this interface.
  	 *
  	 * This must be done before calling ops->remove_interface()
  	 * because otherwise we can later invoke ops->sta_notify()
  	 * whenever the STAs are removed, and that invalidates driver
  	 * assumptions about always getting a vif pointer that is valid
  	 * (because if we remove a STA after ops->remove_interface()
  	 * the driver will have removed the vif info already!)
  	 *
  	 * We could relax this and only unlink the stations from the
  	 * hash table and list but keep them on a per-sdata list that
  	 * will be inserted back again when the interface is brought
  	 * up again, but I don't currently see a use case for that,
  	 * except with WDS which gets a STA entry created when it is
  	 * brought up.
  	 */
  	sta_info_flush(local, sdata);
  
  	/*
  	 * Don't count this interface for promisc/allmulti while it
  	 * is down. dev_mc_unsync() will invoke set_multicast_list
  	 * on the master interface which will sync these down to the
  	 * hardware as filter flags.
  	 */
  	if (sdata->flags & IEEE80211_SDATA_ALLMULTI)
  		atomic_dec(&local->iff_allmultis);
  
  	if (sdata->flags & IEEE80211_SDATA_PROMISC)
  		atomic_dec(&local->iff_promiscs);
  
  	dev_mc_unsync(local->mdev, dev);

  	del_timer_sync(&local->dynamic_ps_timer);
  	cancel_work_sync(&local->dynamic_ps_enable_work);

  
  	/* APs need special treatment */
  	if (sdata->vif.type == NL80211_IFTYPE_AP) {
  		struct ieee80211_sub_if_data *vlan, *tmp;
  		struct beacon_data *old_beacon = sdata->u.ap.beacon;
  
  		/* remove beacon */
  		rcu_assign_pointer(sdata->u.ap.beacon, NULL);
  		synchronize_rcu();
  		kfree(old_beacon);
  
  		/* down all dependent devices, that is VLANs */
  		list_for_each_entry_safe(vlan, tmp, &sdata->u.ap.vlans,
  					 u.vlan.list)
  			dev_close(vlan->dev);
  		WARN_ON(!list_empty(&sdata->u.ap.vlans));
  	}
  
  	local->open_count--;
  
  	switch (sdata->vif.type) {
  	case NL80211_IFTYPE_AP_VLAN:
  		list_del(&sdata->u.vlan.list);
  		/* no need to tell driver */
  		break;
  	case NL80211_IFTYPE_MONITOR:
  		if (sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) {
  			local->cooked_mntrs--;
  			break;
  		}
  
  		local->monitors--;

  		if (local->monitors == 0) {

  			local->hw.conf.flags &= ~IEEE80211_CONF_RADIOTAP;

  			hw_reconf_flags |= IEEE80211_CONF_CHANGE_RADIOTAP;
  		}

  
  		if (sdata->u.mntr_flags & MONITOR_FLAG_FCSFAIL)
  			local->fif_fcsfail--;
  		if (sdata->u.mntr_flags & MONITOR_FLAG_PLCPFAIL)
  			local->fif_plcpfail--;
  		if (sdata->u.mntr_flags & MONITOR_FLAG_CONTROL)
  			local->fif_control--;
  		if (sdata->u.mntr_flags & MONITOR_FLAG_OTHER_BSS)
  			local->fif_other_bss--;
  
  		netif_addr_lock_bh(local->mdev);
  		ieee80211_configure_filter(local);
  		netif_addr_unlock_bh(local->mdev);
  		break;
  	case NL80211_IFTYPE_STATION:

  		memset(sdata->u.mgd.bssid, 0, ETH_ALEN);
  		del_timer_sync(&sdata->u.mgd.chswitch_timer);
  		del_timer_sync(&sdata->u.mgd.timer);

  		/*
  		 * If the timer fired while we waited for it, it will have
  		 * requeued the work. Now the work will be running again
  		 * but will not rearm the timer again because it checks
  		 * whether the interface is running, which, at this point,
  		 * it no longer is.
  		 */

  		cancel_work_sync(&sdata->u.mgd.work);
  		cancel_work_sync(&sdata->u.mgd.chswitch_work);

  
  		cancel_work_sync(&sdata->u.mgd.beacon_loss_work);

  		/*
  		 * When we get here, the interface is marked down.
  		 * Call synchronize_rcu() to wait for the RX path
  		 * should it be using the interface and enqueuing
  		 * frames at this very time on another CPU.
  		 */
  		synchronize_rcu();

  		skb_queue_purge(&sdata->u.mgd.skb_queue);

  		sdata->u.mgd.flags &= ~(IEEE80211_STA_PRIVACY_INVOKED |

  					IEEE80211_STA_TKIP_WEP_USED);

  		kfree(sdata->u.mgd.extra_ie);
  		sdata->u.mgd.extra_ie = NULL;
  		sdata->u.mgd.extra_ie_len = 0;
  		/* fall through */
  	case NL80211_IFTYPE_ADHOC:
  		if (sdata->vif.type == NL80211_IFTYPE_ADHOC) {

  			del_timer_sync(&sdata->u.ibss.timer);
  			cancel_work_sync(&sdata->u.ibss.work);
  			synchronize_rcu();
  			skb_queue_purge(&sdata->u.ibss.skb_queue);
  		}

  		/* fall through */
  	case NL80211_IFTYPE_MESH_POINT:
  		if (ieee80211_vif_is_mesh(&sdata->vif)) {

  			/* other_bss and allmulti are always set on mesh
  			 * ifaces */
  			local->fif_other_bss--;

  			atomic_dec(&local->iff_allmultis);

  
  			netif_addr_lock_bh(local->mdev);
  			ieee80211_configure_filter(local);
  			netif_addr_unlock_bh(local->mdev);

  			ieee80211_stop_mesh(sdata);
  		}
  		/* fall through */
  	default:
  		if (local->scan_sdata == sdata) {
  			if (!local->ops->hw_scan)
  				cancel_delayed_work_sync(&local->scan_work);
  			/*
  			 * The software scan can no longer run now, so we can
  			 * clear out the scan_sdata reference. However, the
  			 * hardware scan may still be running. The complete
  			 * function must be prepared to handle a NULL value.
  			 */
  			local->scan_sdata = NULL;
  			/*
  			 * The memory barrier guarantees that another CPU
  			 * that is hardware-scanning will now see the fact
  			 * that this interface is gone.
  			 */
  			smp_mb();
  			/*
  			 * If software scanning, complete the scan but since
  			 * the scan_sdata is NULL already don't send out a
  			 * scan event to userspace -- the scan is incomplete.
  			 */
  			if (local->sw_scanning)

  				ieee80211_scan_completed(&local->hw, true);

  		}
  
  		conf.vif = &sdata->vif;
  		conf.type = sdata->vif.type;
  		conf.mac_addr = dev->dev_addr;
  		/* disable all keys for as long as this netdev is down */
  		ieee80211_disable_keys(sdata);

  		drv_remove_interface(local, &conf);

  	}
  
  	sdata->bss = NULL;

  	hw_reconf_flags |= __ieee80211_recalc_idle(local);
  
  	ieee80211_recalc_ps(local, -1);

  	if (local->open_count == 0) {
  		if (netif_running(local->mdev))
  			dev_close(local->mdev);

  		drv_stop(local);

  		ieee80211_led_radio(local, false);

  
  		flush_workqueue(local->hw.workqueue);
  
  		tasklet_disable(&local->tx_pending_tasklet);
  		tasklet_disable(&local->tasklet);

  
  		/* no reconfiguring after stop! */
  		hw_reconf_flags = 0;

  	}

  	/* do after stop to avoid reconfiguring when we stop anyway */
  	if (hw_reconf_flags)
  		ieee80211_hw_config(local, hw_reconf_flags);

  	return 0;
  }
  
  static void ieee80211_set_multicast_list(struct net_device *dev)
  {

  	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);

  	struct ieee80211_local *local = sdata->local;

  	int allmulti, promisc, sdata_allmulti, sdata_promisc;
  
  	allmulti = !!(dev->flags & IFF_ALLMULTI);
  	promisc = !!(dev->flags & IFF_PROMISC);
  	sdata_allmulti = !!(sdata->flags & IEEE80211_SDATA_ALLMULTI);
  	sdata_promisc = !!(sdata->flags & IEEE80211_SDATA_PROMISC);
  
  	if (allmulti != sdata_allmulti) {
  		if (dev->flags & IFF_ALLMULTI)
  			atomic_inc(&local->iff_allmultis);
  		else
  			atomic_dec(&local->iff_allmultis);
  		sdata->flags ^= IEEE80211_SDATA_ALLMULTI;
  	}
  
  	if (promisc != sdata_promisc) {
  		if (dev->flags & IFF_PROMISC)
  			atomic_inc(&local->iff_promiscs);
  		else
  			atomic_dec(&local->iff_promiscs);
  		sdata->flags ^= IEEE80211_SDATA_PROMISC;
  	}
  
  	dev_mc_sync(local->mdev, dev);
  }

  /*
   * Called when the netdev is removed or, by the code below, before
   * the interface type changes.
   */
  static void ieee80211_teardown_sdata(struct net_device *dev)

  {

  	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
  	struct ieee80211_local *local = sdata->local;
  	struct beacon_data *beacon;
  	struct sk_buff *skb;
  	int flushed;

  	int i;

  	/* free extra data */
  	ieee80211_free_keys(sdata);

  	ieee80211_debugfs_remove_netdev(sdata);

  	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)

  		__skb_queue_purge(&sdata->fragments[i].skb_list);
  	sdata->fragment_next = 0;

  	switch (sdata->vif.type) {

  	case NL80211_IFTYPE_AP:

  		beacon = sdata->u.ap.beacon;
  		rcu_assign_pointer(sdata->u.ap.beacon, NULL);
  		synchronize_rcu();
  		kfree(beacon);

  		while ((skb = skb_dequeue(&sdata->u.ap.ps_bc_buf))) {
  			local->total_ps_buffered--;
  			dev_kfree_skb(skb);
  		}
  
  		break;

  	case NL80211_IFTYPE_MESH_POINT:

  		if (ieee80211_vif_is_mesh(&sdata->vif))

  			mesh_rmc_free(sdata);

  		break;

  	case NL80211_IFTYPE_ADHOC:

  		if (WARN_ON(sdata->u.ibss.presp))
  			kfree_skb(sdata->u.ibss.presp);

  		break;
  	case NL80211_IFTYPE_STATION:
  		kfree(sdata->u.mgd.extra_ie);
  		kfree(sdata->u.mgd.assocreq_ies);
  		kfree(sdata->u.mgd.assocresp_ies);

  		kfree(sdata->u.mgd.sme_auth_ie);

  		break;

  	case NL80211_IFTYPE_WDS:
  	case NL80211_IFTYPE_AP_VLAN:
  	case NL80211_IFTYPE_MONITOR:

  		break;

  	case NL80211_IFTYPE_UNSPECIFIED:
  	case __NL80211_IFTYPE_AFTER_LAST:

  		BUG();
  		break;
  	}
  
  	flushed = sta_info_flush(local, sdata);
  	WARN_ON(flushed);

  }

  static const struct net_device_ops ieee80211_dataif_ops = {
  	.ndo_open		= ieee80211_open,
  	.ndo_stop		= ieee80211_stop,
  	.ndo_uninit		= ieee80211_teardown_sdata,
  	.ndo_start_xmit		= ieee80211_subif_start_xmit,
  	.ndo_set_multicast_list = ieee80211_set_multicast_list,
  	.ndo_change_mtu 	= ieee80211_change_mtu,
  	.ndo_set_mac_address 	= eth_mac_addr,
  };
  
  static const struct net_device_ops ieee80211_monitorif_ops = {
  	.ndo_open		= ieee80211_open,
  	.ndo_stop		= ieee80211_stop,
  	.ndo_uninit		= ieee80211_teardown_sdata,
  	.ndo_start_xmit		= ieee80211_monitor_start_xmit,
  	.ndo_set_multicast_list = ieee80211_set_multicast_list,
  	.ndo_change_mtu 	= ieee80211_change_mtu,
  	.ndo_set_mac_address 	= eth_mac_addr,
  };
  
  static void ieee80211_if_setup(struct net_device *dev)
  {
  	ether_setup(dev);
  	dev->netdev_ops = &ieee80211_dataif_ops;
  	dev->wireless_handlers = &ieee80211_iw_handler_def;
  	dev->destructor = free_netdev;
  }

  /*
   * Helper function to initialise an interface to a specific type.
   */
  static void ieee80211_setup_sdata(struct ieee80211_sub_if_data *sdata,

  				  enum nl80211_iftype type)

  {

  	/* clear type-dependent union */
  	memset(&sdata->u, 0, sizeof(sdata->u));
  
  	/* and set some type-dependent values */
  	sdata->vif.type = type;

  	sdata->dev->netdev_ops = &ieee80211_dataif_ops;

  	sdata->wdev.iftype = type;

  
  	/* only monitor differs */
  	sdata->dev->type = ARPHRD_ETHER;
  
  	switch (type) {

  	case NL80211_IFTYPE_AP:

  		skb_queue_head_init(&sdata->u.ap.ps_bc_buf);
  		INIT_LIST_HEAD(&sdata->u.ap.vlans);
  		break;

  	case NL80211_IFTYPE_STATION:

  		ieee80211_sta_setup_sdata(sdata);

  		break;

  	case NL80211_IFTYPE_ADHOC:
  		ieee80211_ibss_setup_sdata(sdata);
  		break;

  	case NL80211_IFTYPE_MESH_POINT:

  		if (ieee80211_vif_is_mesh(&sdata->vif))
  			ieee80211_mesh_init_sdata(sdata);
  		break;

  	case NL80211_IFTYPE_MONITOR:

  		sdata->dev->type = ARPHRD_IEEE80211_RADIOTAP;

  		sdata->dev->netdev_ops = &ieee80211_monitorif_ops;

  		sdata->u.mntr_flags = MONITOR_FLAG_CONTROL |
  				      MONITOR_FLAG_OTHER_BSS;
  		break;

  	case NL80211_IFTYPE_WDS:
  	case NL80211_IFTYPE_AP_VLAN:

  		break;

  	case NL80211_IFTYPE_UNSPECIFIED:
  	case __NL80211_IFTYPE_AFTER_LAST:

  		BUG();
  		break;
  	}
  
  	ieee80211_debugfs_add_netdev(sdata);
  }

  int ieee80211_if_change_type(struct ieee80211_sub_if_data *sdata,

  			     enum nl80211_iftype type)

  {

  	ASSERT_RTNL();
  
  	if (type == sdata->vif.type)
  		return 0;

  	/* Setting ad-hoc mode on non-IBSS channel is not supported. */

  	if (sdata->local->oper_channel->flags & IEEE80211_CHAN_NO_IBSS &&
  	    type == NL80211_IFTYPE_ADHOC)

  		return -EOPNOTSUPP;

  	/*
  	 * We could, here, on changes between IBSS/STA/MESH modes,
  	 * invoke an MLME function instead that disassociates etc.
  	 * and goes into the requested mode.
  	 */
  
  	if (netif_running(sdata->dev))
  		return -EBUSY;

  	/* Purge and reset type-dependent state. */
  	ieee80211_teardown_sdata(sdata->dev);
  	ieee80211_setup_sdata(sdata, type);
  
  	/* reset some values that shouldn't be kept across type changes */

  	sdata->vif.bss_conf.basic_rates =

  		ieee80211_mandatory_rates(sdata->local,
  			sdata->local->hw.conf.channel->band);

  	sdata->drop_unencrypted = 0;

  
  	return 0;

  }

  int ieee80211_if_add(struct ieee80211_local *local, const char *name,

  		     struct net_device **new_dev, enum nl80211_iftype type,

  		     struct vif_params *params)

  {
  	struct net_device *ndev;

  	struct ieee80211_sub_if_data *sdata = NULL;

  	int ret, i;

  
  	ASSERT_RTNL();

  	ndev = alloc_netdev(sizeof(*sdata) + local->hw.vif_data_size,

  			    name, ieee80211_if_setup);
  	if (!ndev)
  		return -ENOMEM;

  	ndev->needed_headroom = local->tx_headroom +
  				4*6 /* four MAC addresses */
  				+ 2 + 2 + 2 + 2 /* ctl, dur, seq, qos */
  				+ 6 /* mesh */
  				+ 8 /* rfc1042/bridge tunnel */
  				- ETH_HLEN /* ethernet hard_header_len */
  				+ IEEE80211_ENCRYPT_HEADROOM;
  	ndev->needed_tailroom = IEEE80211_ENCRYPT_TAILROOM;

  	ret = dev_alloc_name(ndev, ndev->name);
  	if (ret < 0)
  		goto fail;
  
  	memcpy(ndev->dev_addr, local->hw.wiphy->perm_addr, ETH_ALEN);

  	SET_NETDEV_DEV(ndev, wiphy_dev(local->hw.wiphy));

  	ndev->features |= NETIF_F_NETNS_LOCAL;

  	/* don't use IEEE80211_DEV_TO_SUB_IF because it checks too much */
  	sdata = netdev_priv(ndev);

  	ndev->ieee80211_ptr = &sdata->wdev;

  
  	/* initialise type-independent data */

  	sdata->wdev.wiphy = local->hw.wiphy;

  	sdata->local = local;

  	sdata->dev = ndev;
  
  	for (i = 0; i < IEEE80211_FRAGMENT_MAX; i++)
  		skb_queue_head_init(&sdata->fragments[i].skb_list);
  
  	INIT_LIST_HEAD(&sdata->key_list);
  
  	sdata->force_unicast_rateidx = -1;
  	sdata->max_ratectrl_rateidx = -1;
  
  	/* setup type-dependent data */
  	ieee80211_setup_sdata(sdata, type);

  
  	ret = register_netdevice(ndev);
  	if (ret)
  		goto fail;

  	if (ieee80211_vif_is_mesh(&sdata->vif) &&
  	    params && params->mesh_id_len)

  		ieee80211_sdata_set_mesh_id(sdata,
  					    params->mesh_id_len,
  					    params->mesh_id);

  	mutex_lock(&local->iflist_mtx);

  	list_add_tail_rcu(&sdata->list, &local->interfaces);

  	mutex_unlock(&local->iflist_mtx);

  	if (new_dev)
  		*new_dev = ndev;

  	return 0;

   fail:

  	free_netdev(ndev);
  	return ret;
  }

  void ieee80211_if_remove(struct ieee80211_sub_if_data *sdata)

  {

  	ASSERT_RTNL();

  	mutex_lock(&sdata->local->iflist_mtx);

  	list_del_rcu(&sdata->list);

  	mutex_unlock(&sdata->local->iflist_mtx);

  	synchronize_rcu();

  	unregister_netdevice(sdata->dev);

  }

  /*
   * Remove all interfaces, may only be called at hardware unregistration
   * time because it doesn't do RCU-safe list removals.
   */
  void ieee80211_remove_interfaces(struct ieee80211_local *local)

  {

  	struct ieee80211_sub_if_data *sdata, *tmp;

  
  	ASSERT_RTNL();

  	list_for_each_entry_safe(sdata, tmp, &local->interfaces, list) {

  		/*
  		 * we cannot hold the iflist_mtx across unregister_netdevice,
  		 * but we only need to hold it for list modifications to lock
  		 * out readers since we're under the RTNL here as all other
  		 * writers.
  		 */
  		mutex_lock(&local->iflist_mtx);

  		list_del(&sdata->list);

  		mutex_unlock(&local->iflist_mtx);

  		unregister_netdevice(sdata->dev);

  	}

  }

  
  static u32 ieee80211_idle_off(struct ieee80211_local *local,
  			      const char *reason)
  {
  	if (!(local->hw.conf.flags & IEEE80211_CONF_IDLE))
  		return 0;
  
  #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  	printk(KERN_DEBUG "%s: device no longer idle - %s
  ",
  	       wiphy_name(local->hw.wiphy), reason);
  #endif
  
  	local->hw.conf.flags &= ~IEEE80211_CONF_IDLE;
  	return IEEE80211_CONF_CHANGE_IDLE;
  }
  
  static u32 ieee80211_idle_on(struct ieee80211_local *local)
  {
  	if (local->hw.conf.flags & IEEE80211_CONF_IDLE)
  		return 0;
  
  #ifdef CONFIG_MAC80211_VERBOSE_DEBUG
  	printk(KERN_DEBUG "%s: device now idle
  ",
  	       wiphy_name(local->hw.wiphy));
  #endif
  
  	local->hw.conf.flags |= IEEE80211_CONF_IDLE;
  	return IEEE80211_CONF_CHANGE_IDLE;
  }
  
  u32 __ieee80211_recalc_idle(struct ieee80211_local *local)
  {
  	struct ieee80211_sub_if_data *sdata;
  	int count = 0;
  
  	if (local->hw_scanning || local->sw_scanning)
  		return ieee80211_idle_off(local, "scanning");
  
  	list_for_each_entry(sdata, &local->interfaces, list) {
  		if (!netif_running(sdata->dev))
  			continue;
  		/* do not count disabled managed interfaces */
  		if (sdata->vif.type == NL80211_IFTYPE_STATION &&
  		    sdata->u.mgd.state == IEEE80211_STA_MLME_DISABLED)
  			continue;
  		/* do not count unused IBSS interfaces */
  		if (sdata->vif.type == NL80211_IFTYPE_ADHOC &&
  		    !sdata->u.ibss.ssid_len)
  			continue;
  		/* count everything else */
  		count++;
  	}
  
  	if (!count)
  		return ieee80211_idle_on(local);
  	else
  		return ieee80211_idle_off(local, "in use");
  
  	return 0;
  }
  
  void ieee80211_recalc_idle(struct ieee80211_local *local)
  {
  	u32 chg;
  
  	mutex_lock(&local->iflist_mtx);
  	chg = __ieee80211_recalc_idle(local);
  	mutex_unlock(&local->iflist_mtx);

  	if (chg)
  		ieee80211_hw_config(local, chg);

  }