/* * Interface handling (except master interface) * * Copyright 2002-2005, Instant802 Networks, Inc. * Copyright 2005-2006, Devicescape Software, Inc. * Copyright (c) 2006 Jiri Benc * Copyright 2008, Johannes Berg * * 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 #include #include #include #include #include "ieee80211_i.h" #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 = 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 = 0; if (local->ops->start) res = local->ops->start(local_to_hw(local)); if (res) goto err_del_bss; /* we're brought up, everything changes */ hw_reconf_flags = ~0; 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; 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: 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)) { 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 && !(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 (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_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; 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(sdata, sta->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; 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: case NL80211_IFTYPE_ADHOC: /* Announce that we are leaving the network. */ if (sdata->u.sta.state != IEEE80211_STA_MLME_DISABLED) ieee80211_sta_deauthenticate(sdata, WLAN_REASON_DEAUTH_LEAVING); 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)) { /* 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); } 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); /* 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); } 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. */ 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_STATION: case NL80211_IFTYPE_ADHOC: kfree(sdata->u.sta.extra_ie); kfree(sdata->u.sta.assocreq_ies); kfree(sdata->u.sta.assocresp_ies); kfree_skb(sdata->u.sta.probe_resp); 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); } /* * 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->hard_start_xmit = ieee80211_subif_start_xmit; 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: case NL80211_IFTYPE_ADHOC: ieee80211_sta_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->hard_start_xmit = ieee80211_monitor_start_xmit; 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; /* * 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)); /* 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; ndev->uninit = ieee80211_teardown_sdata; 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); list_add_tail_rcu(&sdata->list, &local->interfaces); 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(); list_del_rcu(&sdata->list); 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) { list_del(&sdata->list); unregister_netdevice(sdata->dev); } }