mac80211: move regular interface handling
authorJohannes Berg <johannes@sipsolutions.net>
Wed, 10 Sep 2008 22:01:59 +0000 (00:01 +0200)
committerJohn W. Linville <linville@tuxdriver.com>
Mon, 15 Sep 2008 20:48:23 +0000 (16:48 -0400)
Move the code to handle regular interfaces out of main.c and
into iface.c, keep only the master interface stuff in main.c.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
net/mac80211/ieee80211_i.h
net/mac80211/iface.c
net/mac80211/main.c

index 80d88f5..6bd6a63 100644 (file)
@@ -891,6 +891,7 @@ u32 ieee80211_handle_ht(struct ieee80211_local *local, int enable_ht,
                        struct ieee80211_ht_bss_info *req_bss_cap);
 void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
                                      u32 changed);
+void ieee80211_configure_filter(struct ieee80211_local *local);
 
 /* wireless extensions */
 extern const struct iw_handler_def ieee80211_iw_handler_def;
@@ -952,7 +953,6 @@ void ieee80211_rx_bss_put(struct ieee80211_local *local,
                          struct ieee80211_bss *bss);
 
 /* interface handling */
-void ieee80211_if_setup(struct net_device *dev);
 int ieee80211_if_add(struct ieee80211_local *local, const char *name,
                     struct net_device **new_dev, enum nl80211_iftype type,
                     struct vif_params *params);
index 004fb23..f528962 100644 (file)
@@ -1,4 +1,6 @@
 /*
+ * 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>
 #include "sta_info.h"
 #include "debugfs_netdev.h"
 #include "mesh.h"
+#include "led.h"
+
+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\n", 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, *nsdata;
+       struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+       struct sta_info *sta;
+       struct ieee80211_if_init_conf conf;
+       u32 changed = 0;
+       int res;
+       bool need_hw_reconfig = 0;
+       u8 null_addr[ETH_ALEN] = {0};
+
+       sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+
+       /* 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 = 0;
+               if (local->ops->start)
+                       res = local->ops->start(local_to_hw(local));
+               if (res)
+                       goto err_del_bss;
+               need_hw_reconfig = 1;
+               ieee80211_led_radio(local, local->hw.conf.radio_enabled);
+       }
 
+       /*
+        * 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 && local->ops->stop)
+                       local->ops->stop(local_to_hw(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;
+
+               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:
+       case NL80211_IFTYPE_ADHOC:
+               sdata->u.sta.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 = local->ops->add_interface(local_to_hw(local), &conf);
+               if (res)
+                       goto err_stop;
+
+               if (ieee80211_vif_is_mesh(&sdata->vif))
+                       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 &&
+                   !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
+                       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);
+
+       local->open_count++;
+       if (need_hw_reconfig) {
+               ieee80211_hw_config(local);
+               /*
+                * 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_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 ||
+           sdata->vif.type == NL80211_IFTYPE_ADHOC) {
+               struct ieee80211_if_sta *ifsta = &sdata->u.sta;
+               queue_work(local->hw.workqueue, &ifsta->work);
+       }
+
+       netif_tx_start_all_queues(dev);
+
+       return 0;
+ err_del_interface:
+       local->ops->remove_interface(local_to_hw(local), &conf);
+ err_stop:
+       if (!local->open_count && local->ops->stop)
+               local->ops->stop(local_to_hw(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;
+
+       /*
+        * 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(sdata, sta->addr);
+       }
+
+       rcu_read_unlock();
+
+       /*
+        * 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);
+
+       /* 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;
+
+               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:
+       case NL80211_IFTYPE_ADHOC:
+               sdata->u.sta.state = IEEE80211_STA_MLME_DISABLED;
+               memset(sdata->u.sta.bssid, 0, ETH_ALEN);
+               del_timer_sync(&sdata->u.sta.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.sta.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.sta.skb_queue);
+
+               sdata->u.sta.flags &= ~IEEE80211_STA_PRIVACY_INVOKED;
+               kfree(sdata->u.sta.extra_ie);
+               sdata->u.sta.extra_ie = NULL;
+               sdata->u.sta.extra_ie_len = 0;
+               /* fall through */
+       case NL80211_IFTYPE_MESH_POINT:
+               if (ieee80211_vif_is_mesh(&sdata->vif)) {
+                       /* allmulti is always set on mesh ifaces */
+                       atomic_dec(&local->iff_allmultis);
+                       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);
+               }
+
+               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);
+               local->ops->remove_interface(local_to_hw(local), &conf);
+       }
+
+       sdata->bss = NULL;
+
+       if (local->open_count == 0) {
+               if (netif_running(local->mdev))
+                       dev_close(local->mdev);
+
+               if (local->ops->stop)
+                       local->ops->stop(local_to_hw(local));
+
+               ieee80211_led_radio(local, 0);
+
+               flush_workqueue(local->hw.workqueue);
+
+               tasklet_disable(&local->tx_pending_tasklet);
+               tasklet_disable(&local->tasklet);
+       }
+
+       return 0;
+}
+
+static void ieee80211_set_multicast_list(struct net_device *dev)
+{
+       struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+       struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+       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);
+}
+
+static void ieee80211_if_setup(struct net_device *dev)
+{
+       ether_setup(dev);
+       dev->hard_start_xmit = ieee80211_subif_start_xmit;
+       dev->wireless_handlers = &ieee80211_iw_handler_def;
+       dev->set_multicast_list = ieee80211_set_multicast_list;
+       dev->change_mtu = ieee80211_change_mtu;
+       dev->open = ieee80211_open;
+       dev->stop = ieee80211_stop;
+       dev->destructor = free_netdev;
+       /* we will validate the address ourselves in ->open */
+       dev->validate_addr = NULL;
+}
 /*
  * Called when the netdev is removed or, by the code below, before
  * the interface type changes.
index 584a75b..c532043 100644 (file)
@@ -45,16 +45,9 @@ struct ieee80211_tx_status_rtap_hdr {
        u8 data_retries;
 } __attribute__ ((packed));
 
-/* common interface routines */
-
-static int header_parse_80211(const struct sk_buff *skb, unsigned char *haddr)
-{
-       memcpy(haddr, skb_mac_header(skb) + 10, ETH_ALEN); /* addr2 */
-       return ETH_ALEN;
-}
 
 /* must be called under mdev tx lock */
-static void ieee80211_configure_filter(struct ieee80211_local *local)
+void ieee80211_configure_filter(struct ieee80211_local *local)
 {
        unsigned int changed_flags;
        unsigned int new_flags = 0;
@@ -97,6 +90,20 @@ static void ieee80211_configure_filter(struct ieee80211_local *local)
 
 /* master interface */
 
+static int header_parse_80211(const struct sk_buff *skb, unsigned char *haddr)
+{
+       memcpy(haddr, skb_mac_header(skb) + 10, ETH_ALEN); /* addr2 */
+       return ETH_ALEN;
+}
+
+static const struct header_ops ieee80211_header_ops = {
+       .create         = eth_header,
+       .parse          = header_parse_80211,
+       .rebuild        = eth_rebuild_header,
+       .cache          = eth_header_cache,
+       .cache_update   = eth_header_cache_update,
+};
+
 static int ieee80211_master_open(struct net_device *dev)
 {
        struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
@@ -139,548 +146,6 @@ static void ieee80211_master_set_multicast_list(struct net_device *dev)
        ieee80211_configure_filter(local);
 }
 
-/* regular interfaces */
-
-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\n", 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, *nsdata;
-       struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
-       struct sta_info *sta;
-       struct ieee80211_if_init_conf conf;
-       u32 changed = 0;
-       int res;
-       bool need_hw_reconfig = 0;
-       u8 null_addr[ETH_ALEN] = {0};
-
-       sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-
-       /* 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 = 0;
-               if (local->ops->start)
-                       res = local->ops->start(local_to_hw(local));
-               if (res)
-                       goto err_del_bss;
-               need_hw_reconfig = 1;
-               ieee80211_led_radio(local, local->hw.conf.radio_enabled);
-       }
-
-       /*
-        * 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 && local->ops->stop)
-                       local->ops->stop(local_to_hw(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;
-
-               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:
-       case NL80211_IFTYPE_ADHOC:
-               sdata->u.sta.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 = local->ops->add_interface(local_to_hw(local), &conf);
-               if (res)
-                       goto err_stop;
-
-               if (ieee80211_vif_is_mesh(&sdata->vif))
-                       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 &&
-                   !(sdata->flags & IEEE80211_SDATA_USERSPACE_MLME))
-                       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);
-
-       local->open_count++;
-       if (need_hw_reconfig) {
-               ieee80211_hw_config(local);
-               /*
-                * 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_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 ||
-           sdata->vif.type == NL80211_IFTYPE_ADHOC) {
-               struct ieee80211_if_sta *ifsta = &sdata->u.sta;
-               queue_work(local->hw.workqueue, &ifsta->work);
-       }
-
-       netif_tx_start_all_queues(dev);
-
-       return 0;
- err_del_interface:
-       local->ops->remove_interface(local_to_hw(local), &conf);
- err_stop:
-       if (!local->open_count && local->ops->stop)
-               local->ops->stop(local_to_hw(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;
-
-       /*
-        * 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(sdata, sta->addr);
-       }
-
-       rcu_read_unlock();
-
-       /*
-        * 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);
-
-       /* 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;
-
-               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:
-       case NL80211_IFTYPE_ADHOC:
-               sdata->u.sta.state = IEEE80211_STA_MLME_DISABLED;
-               memset(sdata->u.sta.bssid, 0, ETH_ALEN);
-               del_timer_sync(&sdata->u.sta.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.sta.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.sta.skb_queue);
-
-               sdata->u.sta.flags &= ~IEEE80211_STA_PRIVACY_INVOKED;
-               kfree(sdata->u.sta.extra_ie);
-               sdata->u.sta.extra_ie = NULL;
-               sdata->u.sta.extra_ie_len = 0;
-               /* fall through */
-       case NL80211_IFTYPE_MESH_POINT:
-               if (ieee80211_vif_is_mesh(&sdata->vif)) {
-                       /* allmulti is always set on mesh ifaces */
-                       atomic_dec(&local->iff_allmultis);
-                       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);
-               }
-
-               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);
-               local->ops->remove_interface(local_to_hw(local), &conf);
-       }
-
-       sdata->bss = NULL;
-
-       if (local->open_count == 0) {
-               if (netif_running(local->mdev))
-                       dev_close(local->mdev);
-
-               if (local->ops->stop)
-                       local->ops->stop(local_to_hw(local));
-
-               ieee80211_led_radio(local, 0);
-
-               flush_workqueue(local->hw.workqueue);
-
-               tasklet_disable(&local->tx_pending_tasklet);
-               tasklet_disable(&local->tasklet);
-       }
-
-       return 0;
-}
-
-static void ieee80211_set_multicast_list(struct net_device *dev)
-{
-       struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
-       struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-       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);
-}
-
-static const struct header_ops ieee80211_header_ops = {
-       .create         = eth_header,
-       .parse          = header_parse_80211,
-       .rebuild        = eth_rebuild_header,
-       .cache          = eth_header_cache,
-       .cache_update   = eth_header_cache_update,
-};
-
-void ieee80211_if_setup(struct net_device *dev)
-{
-       ether_setup(dev);
-       dev->hard_start_xmit = ieee80211_subif_start_xmit;
-       dev->wireless_handlers = &ieee80211_iw_handler_def;
-       dev->set_multicast_list = ieee80211_set_multicast_list;
-       dev->change_mtu = ieee80211_change_mtu;
-       dev->open = ieee80211_open;
-       dev->stop = ieee80211_stop;
-       dev->destructor = free_netdev;
-       /* we will validate the address ourselves in ->open */
-       dev->validate_addr = NULL;
-}
-
 /* everything else */
 
 int ieee80211_if_config(struct ieee80211_sub_if_data *sdata, u32 changed)