/*
 * Copyright 2002-2005, Instant802 Networks, Inc.
 * Copyright 2005-2006, Devicescape Software, Inc.
 * Copyright 2006-2007  Jiri Benc <jbenc@suse.cz>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <net/mac80211.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/netdevice.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/skbuff.h>
#include <linux/etherdevice.h>
#include <linux/if_arp.h>
#include <linux/rtnetlink.h>
#include <linux/bitmap.h>
#include <linux/pm_qos.h>
#include <linux/inetdevice.h>
#include <net/net_namespace.h>
#include <net/cfg80211.h>
#include <net/addrconf.h>

#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"
#include "mesh.h"
#include "wep.h"
#include "led.h"
#include "cfg.h"
#include "debugfs.h"

void ieee80211_configure_filter(struct ieee80211_local *local)
{
        u64 mc;
        unsigned int changed_flags;
        unsigned int new_flags = 0;

        if (atomic_read(&local->iff_promiscs))
                new_flags |= FIF_PROMISC_IN_BSS;

        if (atomic_read(&local->iff_allmultis))
                new_flags |= FIF_ALLMULTI;

        if (local->monitors || test_bit(SCAN_SW_SCANNING, &local->scanning) ||
            test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning))
                new_flags |= FIF_BCN_PRBRESP_PROMISC;

        if (local->fif_probe_req || local->probe_req_reg)
                new_flags |= FIF_PROBE_REQ;

        if (local->fif_fcsfail)
                new_flags |= FIF_FCSFAIL;

        if (local->fif_plcpfail)
                new_flags |= FIF_PLCPFAIL;

        if (local->fif_control)
                new_flags |= FIF_CONTROL;

        if (local->fif_other_bss)
                new_flags |= FIF_OTHER_BSS;

        if (local->fif_pspoll)
                new_flags |= FIF_PSPOLL;

        spin_lock_bh(&local->filter_lock);
        changed_flags = local->filter_flags ^ new_flags;

        mc = drv_prepare_multicast(local, &local->mc_list);
        spin_unlock_bh(&local->filter_lock);

        /* be a bit nasty */
        new_flags |= (1<<31);

        drv_configure_filter(local, changed_flags, &new_flags, mc);

        WARN_ON(new_flags & (1<<31));

        local->filter_flags = new_flags & ~(1<<31);
}

static void ieee80211_reconfig_filter(struct work_struct *work)
{
        struct ieee80211_local *local =
                container_of(work, struct ieee80211_local, reconfig_filter);

        ieee80211_configure_filter(local);
}

static u32 ieee80211_hw_conf_chan(struct ieee80211_local *local)
{
        struct ieee80211_sub_if_data *sdata;
        struct cfg80211_chan_def chandef = {};
        u32 changed = 0;
        int power;
        u32 offchannel_flag;

        offchannel_flag = local->hw.conf.flags & IEEE80211_CONF_OFFCHANNEL;

        if (local->scan_channel) {
                chandef.chan = local->scan_channel;
                /* If scanning on oper channel, use whatever channel-type
                 * is currently in use.
                 */
                if (chandef.chan == local->_oper_chandef.chan) {
                        chandef = local->_oper_chandef;
                } else {
                        chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
                        chandef.center_freq1 = chandef.chan->center_freq;
                }
        } else if (local->tmp_channel) {
                chandef.chan = local->tmp_channel;
                chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
                chandef.center_freq1 = chandef.chan->center_freq;
        } else
                chandef = local->_oper_chandef;

        WARN(!cfg80211_chandef_valid(&chandef),
             "control:%d MHz width:%d center: %d/%d MHz",
             chandef.chan->center_freq, chandef.width,
             chandef.center_freq1, chandef.center_freq2);

        if (!cfg80211_chandef_identical(&chandef, &local->_oper_chandef))
                local->hw.conf.flags |= IEEE80211_CONF_OFFCHANNEL;
        else
                local->hw.conf.flags &= ~IEEE80211_CONF_OFFCHANNEL;

        offchannel_flag ^= local->hw.conf.flags & IEEE80211_CONF_OFFCHANNEL;

        if (offchannel_flag ||
            !cfg80211_chandef_identical(&local->hw.conf.chandef,
                                        &local->_oper_chandef)) {
                local->hw.conf.chandef = chandef;
                changed |= IEEE80211_CONF_CHANGE_CHANNEL;
        }

        if (!conf_is_ht(&local->hw.conf)) {
                /*
                 * mac80211.h documents that this is only valid
                 * when the channel is set to an HT type, and
                 * that otherwise STATIC is used.
                 */
                local->hw.conf.smps_mode = IEEE80211_SMPS_STATIC;
        } else if (local->hw.conf.smps_mode != local->smps_mode) {
                local->hw.conf.smps_mode = local->smps_mode;
                changed |= IEEE80211_CONF_CHANGE_SMPS;
        }

        power = chandef.chan->max_power;

        rcu_read_lock();
        list_for_each_entry_rcu(sdata, &local->interfaces, list) {
                if (!rcu_access_pointer(sdata->vif.chanctx_conf))
                        continue;
                power = min(power, sdata->vif.bss_conf.txpower);
        }
        rcu_read_unlock();

        if (local->hw.conf.power_level != power) {
                changed |= IEEE80211_CONF_CHANGE_POWER;
                local->hw.conf.power_level = power;
        }

        return changed;
}

int ieee80211_hw_config(struct ieee80211_local *local, u32 changed)
{
        int ret = 0;

        might_sleep();

        if (!local->use_chanctx)
                changed |= ieee80211_hw_conf_chan(local);
        else
                changed &= ~(IEEE80211_CONF_CHANGE_CHANNEL |
                             IEEE80211_CONF_CHANGE_POWER);

        if (changed && local->open_count) {
                ret = drv_config(local, changed);
                /*
                 * Goal:
                 * HW reconfiguration should never fail, the driver has told
                 * us what it can support so it should live up to that promise.
                 *
                 * Current status:
                 * rfkill is not integrated with mac80211 and a
                 * configuration command can thus fail if hardware rfkill
                 * is enabled
                 *
                 * FIXME: integrate rfkill with mac80211 and then add this
                 * WARN_ON() back
                 *
                 */
                /* WARN_ON(ret); */
        }

        return ret;
}

void ieee80211_bss_info_change_notify(struct ieee80211_sub_if_data *sdata,
                                      u32 changed)
{
        struct ieee80211_local *local = sdata->local;

        if (!changed)
                return;

        drv_bss_info_changed(local, sdata, &sdata->vif.bss_conf, changed);
}

u32 ieee80211_reset_erp_info(struct ieee80211_sub_if_data *sdata)
{
        sdata->vif.bss_conf.use_cts_prot = false;
        sdata->vif.bss_conf.use_short_preamble = false;
        sdata->vif.bss_conf.use_short_slot = false;
        return BSS_CHANGED_ERP_CTS_PROT |
               BSS_CHANGED_ERP_PREAMBLE |
               BSS_CHANGED_ERP_SLOT;
}

static void ieee80211_tasklet_handler(unsigned long data)
{
        struct ieee80211_local *local = (struct ieee80211_local *) data;
        struct sk_buff *skb;

        while ((skb = skb_dequeue(&local->skb_queue)) ||
               (skb = skb_dequeue(&local->skb_queue_unreliable))) {
                switch (skb->pkt_type) {
                case IEEE80211_RX_MSG:
                        /* Clear skb->pkt_type in order to not confuse kernel
                         * netstack. */
                        skb->pkt_type = 0;
                        ieee80211_rx(&local->hw, skb);
                        break;
                case IEEE80211_TX_STATUS_MSG:
                        skb->pkt_type = 0;
                        ieee80211_tx_status(&local->hw, skb);
                        break;
                default:
                        WARN(1, "mac80211: Packet is of unknown type %d\n",
                             skb->pkt_type);
                        dev_kfree_skb(skb);
                        break;
                }
        }
}

static void ieee80211_restart_work(struct work_struct *work)
{
        struct ieee80211_local *local =
                container_of(work, struct ieee80211_local, restart_work);

        /* wait for scan work complete */
        flush_workqueue(local->workqueue);

        mutex_lock(&local->mtx);
        WARN(test_bit(SCAN_HW_SCANNING, &local->scanning) ||
             rcu_dereference_protected(local->sched_scan_sdata,
                                       lockdep_is_held(&local->mtx)),
                "%s called with hardware scan in progress\n", __func__);
        mutex_unlock(&local->mtx);

        rtnl_lock();
        ieee80211_scan_cancel(local);
        ieee80211_reconfig(local);
        rtnl_unlock();
}

void ieee80211_restart_hw(struct ieee80211_hw *hw)
{
        struct ieee80211_local *local = hw_to_local(hw);

        trace_api_restart_hw(local);

        wiphy_info(hw->wiphy,
                   "Hardware restart was requested\n");

        /* use this reason, ieee80211_reconfig will unblock it */
        ieee80211_stop_queues_by_reason(hw, IEEE80211_MAX_QUEUE_MAP,
                                        IEEE80211_QUEUE_STOP_REASON_SUSPEND);

        /*
         * Stop all Rx during the reconfig. We don't want state changes
         * or driver callbacks while this is in progress.
         */
        local->in_reconfig = true;
        barrier();

        schedule_work(&local->restart_work);
}
EXPORT_SYMBOL(ieee80211_restart_hw);

#ifdef CONFIG_INET
static int ieee80211_ifa_changed(struct notifier_block *nb,
                                 unsigned long data, void *arg)
{
        struct in_ifaddr *ifa = arg;
        struct ieee80211_local *local =
                container_of(nb, struct ieee80211_local,
                             ifa_notifier);
        struct net_device *ndev = ifa->ifa_dev->dev;
        struct wireless_dev *wdev = ndev->ieee80211_ptr;
        struct in_device *idev;
        struct ieee80211_sub_if_data *sdata;
        struct ieee80211_bss_conf *bss_conf;
        struct ieee80211_if_managed *ifmgd;
        int c = 0;

        /* Make sure it's our interface that got changed */
        if (!wdev)
                return NOTIFY_DONE;

        if (wdev->wiphy != local->hw.wiphy)
                return NOTIFY_DONE;

        sdata = IEEE80211_DEV_TO_SUB_IF(ndev);
        bss_conf = &sdata->vif.bss_conf;

        /* ARP filtering is only supported in managed mode */
        if (sdata->vif.type != NL80211_IFTYPE_STATION)
                return NOTIFY_DONE;

        idev = __in_dev_get_rtnl(sdata->dev);
        if (!idev)
                return NOTIFY_DONE;

        ifmgd = &sdata->u.mgd;
        sdata_lock(sdata);

        /* Copy the addresses to the bss_conf list */
        ifa = idev->ifa_list;
        while (ifa) {
                if (c < IEEE80211_BSS_ARP_ADDR_LIST_LEN)
                        bss_conf->arp_addr_list[c] = ifa->ifa_address;
                ifa = ifa->ifa_next;
                c++;
        }

        bss_conf->arp_addr_cnt = c;

        /* Configure driver only if associated (which also implies it is up) */
        if (ifmgd->associated)
                ieee80211_bss_info_change_notify(sdata,
                                                 BSS_CHANGED_ARP_FILTER);

        sdata_unlock(sdata);

        return NOTIFY_DONE;
}
#endif

#if IS_ENABLED(CONFIG_IPV6)
static int ieee80211_ifa6_changed(struct notifier_block *nb,
                                  unsigned long data, void *arg)
{
        struct inet6_ifaddr *ifa = (struct inet6_ifaddr *)arg;
        struct inet6_dev *idev = ifa->idev;
        struct net_device *ndev = ifa->idev->dev;
        struct ieee80211_local *local =
                container_of(nb, struct ieee80211_local, ifa6_notifier);
        struct wireless_dev *wdev = ndev->ieee80211_ptr;
        struct ieee80211_sub_if_data *sdata;

        /* Make sure it's our interface that got changed */
        if (!wdev || wdev->wiphy != local->hw.wiphy)
                return NOTIFY_DONE;

        sdata = IEEE80211_DEV_TO_SUB_IF(ndev);

        /*
         * For now only support station mode. This is mostly because
         * doing AP would have to handle AP_VLAN in some way ...
         */
        if (sdata->vif.type != NL80211_IFTYPE_STATION)
                return NOTIFY_DONE;

        drv_ipv6_addr_change(local, sdata, idev);

        return NOTIFY_DONE;
}
#endif

/* There isn't a lot of sense in it, but you can transmit anything you like */
static const struct ieee80211_txrx_stypes
ieee80211_default_mgmt_stypes[NUM_NL80211_IFTYPES] = {
        [NL80211_IFTYPE_ADHOC] = {
                .tx = 0xffff,
                .rx = BIT(IEEE80211_STYPE_ACTION >> 4) |
                        BIT(IEEE80211_STYPE_AUTH >> 4) |
                        BIT(IEEE80211_STYPE_DEAUTH >> 4) |
                        BIT(IEEE80211_STYPE_PROBE_REQ >> 4),
        },
        [NL80211_IFTYPE_STATION] = {
                .tx = 0xffff,
                .rx = BIT(IEEE80211_STYPE_ACTION >> 4) |
                        BIT(IEEE80211_STYPE_PROBE_REQ >> 4),
        },
        [NL80211_IFTYPE_AP] = {
                .tx = 0xffff,
                .rx = BIT(IEEE80211_STYPE_ASSOC_REQ >> 4) |
                        BIT(IEEE80211_STYPE_REASSOC_REQ >> 4) |
                        BIT(IEEE80211_STYPE_PROBE_REQ >> 4) |
                        BIT(IEEE80211_STYPE_DISASSOC >> 4) |
                        BIT(IEEE80211_STYPE_AUTH >> 4) |
                        BIT(IEEE80211_STYPE_DEAUTH >> 4) |
                        BIT(IEEE80211_STYPE_ACTION >> 4),
        },
        [NL80211_IFTYPE_AP_VLAN] = {
                /* copy AP */
                .tx = 0xffff,
                .rx = BIT(IEEE80211_STYPE_ASSOC_REQ >> 4) |
                        BIT(IEEE80211_STYPE_REASSOC_REQ >> 4) |
                        BIT(IEEE80211_STYPE_PROBE_REQ >> 4) |
                        BIT(IEEE80211_STYPE_DISASSOC >> 4) |
                        BIT(IEEE80211_STYPE_AUTH >> 4) |
                        BIT(IEEE80211_STYPE_DEAUTH >> 4) |
                        BIT(IEEE80211_STYPE_ACTION >> 4),
        },
        [NL80211_IFTYPE_P2P_CLIENT] = {
                .tx = 0xffff,
                .rx = BIT(IEEE80211_STYPE_ACTION >> 4) |
                        BIT(IEEE80211_STYPE_PROBE_REQ >> 4),
        },
        [NL80211_IFTYPE_P2P_GO] = {
                .tx = 0xffff,
                .rx = BIT(IEEE80211_STYPE_ASSOC_REQ >> 4) |
                        BIT(IEEE80211_STYPE_REASSOC_REQ >> 4) |
                        BIT(IEEE80211_STYPE_PROBE_REQ >> 4) |
                        BIT(IEEE80211_STYPE_DISASSOC >> 4) |
                        BIT(IEEE80211_STYPE_AUTH >> 4) |
                        BIT(IEEE80211_STYPE_DEAUTH >> 4) |
                        BIT(IEEE80211_STYPE_ACTION >> 4),
        },
        [NL80211_IFTYPE_MESH_POINT] = {
                .tx = 0xffff,
                .rx = BIT(IEEE80211_STYPE_ACTION >> 4) |
                        BIT(IEEE80211_STYPE_AUTH >> 4) |
                        BIT(IEEE80211_STYPE_DEAUTH >> 4),
        },
        [NL80211_IFTYPE_P2P_DEVICE] = {
                .tx = 0xffff,
                .rx = BIT(IEEE80211_STYPE_ACTION >> 4) |
                        BIT(IEEE80211_STYPE_PROBE_REQ >> 4),
        },
};

static const struct ieee80211_ht_cap mac80211_ht_capa_mod_mask = {
        .ampdu_params_info = IEEE80211_HT_AMPDU_PARM_FACTOR |
                             IEEE80211_HT_AMPDU_PARM_DENSITY,

        .cap_info = cpu_to_le16(IEEE80211_HT_CAP_SUP_WIDTH_20_40 |
                                IEEE80211_HT_CAP_MAX_AMSDU |
                                IEEE80211_HT_CAP_SGI_20 |
                                IEEE80211_HT_CAP_SGI_40),
        .mcs = {
                .rx_mask = { 0xff, 0xff, 0xff, 0xff, 0xff,
                             0xff, 0xff, 0xff, 0xff, 0xff, },
        },
};

static const struct ieee80211_vht_cap mac80211_vht_capa_mod_mask = {
        .vht_cap_info =
                cpu_to_le32(IEEE80211_VHT_CAP_RXLDPC |
                            IEEE80211_VHT_CAP_SHORT_GI_80 |
                            IEEE80211_VHT_CAP_SHORT_GI_160 |
                            IEEE80211_VHT_CAP_RXSTBC_1 |
                            IEEE80211_VHT_CAP_RXSTBC_2 |
                            IEEE80211_VHT_CAP_RXSTBC_3 |
                            IEEE80211_VHT_CAP_RXSTBC_4 |
                            IEEE80211_VHT_CAP_TXSTBC |
                            IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE |
                            IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE |
                            IEEE80211_VHT_CAP_TX_ANTENNA_PATTERN |
                            IEEE80211_VHT_CAP_RX_ANTENNA_PATTERN |
                            IEEE80211_VHT_CAP_MAX_A_MPDU_LENGTH_EXPONENT_MASK),
        .supp_mcs = {
                .rx_mcs_map = cpu_to_le16(~0),
                .tx_mcs_map = cpu_to_le16(~0),
        },
};

static const u8 extended_capabilities[] = {
        0, 0, 0, 0, 0, 0, 0,
        WLAN_EXT_CAPA8_OPMODE_NOTIF,
};

struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len,
                                        const struct ieee80211_ops *ops)
{
        struct ieee80211_local *local;
        int priv_size, i;
        struct wiphy *wiphy;
        bool use_chanctx;

        if (WARN_ON(!ops->tx || !ops->start || !ops->stop || !ops->config ||
                    !ops->add_interface || !ops->remove_interface ||
                    !ops->configure_filter))
                return NULL;

        if (WARN_ON(ops->sta_state && (ops->sta_add || ops->sta_remove)))
                return NULL;

        /* check all or no channel context operations exist */
        i = !!ops->add_chanctx + !!ops->remove_chanctx +
            !!ops->change_chanctx + !!ops->assign_vif_chanctx +
            !!ops->unassign_vif_chanctx;
        if (WARN_ON(i != 0 && i != 5))
                return NULL;
        use_chanctx = i == 5;

        /* Ensure 32-byte alignment of our private data and hw private data.
         * We use the wiphy priv data for both our ieee80211_local and for
         * the driver's private data
         *
         * In memory it'll be like this:
         *
         * +-------------------------+
         * | struct wiphy           |
         * +-------------------------+
         * | struct ieee80211_local  |
         * +-------------------------+
         * | driver's private data   |
         * +-------------------------+
         *
         */
        priv_size = ALIGN(sizeof(*local), NETDEV_ALIGN) + priv_data_len;

        wiphy = wiphy_new(&mac80211_config_ops, priv_size);

        if (!wiphy)
                return NULL;

        wiphy->mgmt_stypes = ieee80211_default_mgmt_stypes;

        wiphy->privid = mac80211_wiphy_privid;

        wiphy->flags |= WIPHY_FLAG_NETNS_OK |
                        WIPHY_FLAG_4ADDR_AP |
                        WIPHY_FLAG_4ADDR_STATION |
                        WIPHY_FLAG_REPORTS_OBSS |
                        WIPHY_FLAG_OFFCHAN_TX;

        wiphy->extended_capabilities = extended_capabilities;
        wiphy->extended_capabilities_mask = extended_capabilities;
        wiphy->extended_capabilities_len = ARRAY_SIZE(extended_capabilities);

        if (ops->remain_on_channel)
                wiphy->flags |= WIPHY_FLAG_HAS_REMAIN_ON_CHANNEL;

        wiphy->features |= NL80211_FEATURE_SK_TX_STATUS |
                           NL80211_FEATURE_SAE |
                           NL80211_FEATURE_HT_IBSS |
                           NL80211_FEATURE_VIF_TXPOWER |
                           NL80211_FEATURE_USERSPACE_MPM;

        if (!ops->hw_scan)
                wiphy->features |= NL80211_FEATURE_LOW_PRIORITY_SCAN |
                                   NL80211_FEATURE_AP_SCAN;


        if (!ops->set_key)
                wiphy->flags |= WIPHY_FLAG_IBSS_RSN;

        wiphy->bss_priv_size = sizeof(struct ieee80211_bss);

        local = wiphy_priv(wiphy);

        local->hw.wiphy = wiphy;

        local->hw.priv = (char *)local + ALIGN(sizeof(*local), NETDEV_ALIGN);

        local->ops = ops;
        local->use_chanctx = use_chanctx;

        /* set up some defaults */
        local->hw.queues = 1;
        local->hw.max_rates = 1;
        local->hw.max_report_rates = 0;
        local->hw.max_rx_aggregation_subframes = IEEE80211_MAX_AMPDU_BUF;
        local->hw.max_tx_aggregation_subframes = IEEE80211_MAX_AMPDU_BUF;
        local->hw.offchannel_tx_hw_queue = IEEE80211_INVAL_HW_QUEUE;
        local->hw.conf.long_frame_max_tx_count = wiphy->retry_long;
        local->hw.conf.short_frame_max_tx_count = wiphy->retry_short;
        local->hw.radiotap_mcs_details = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
                                         IEEE80211_RADIOTAP_MCS_HAVE_GI |
                                         IEEE80211_RADIOTAP_MCS_HAVE_BW;
        local->hw.radiotap_vht_details = IEEE80211_RADIOTAP_VHT_KNOWN_GI |
                                         IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH;
        local->hw.uapsd_queues = IEEE80211_DEFAULT_UAPSD_QUEUES;
        local->hw.uapsd_max_sp_len = IEEE80211_DEFAULT_MAX_SP_LEN;
        local->user_power_level = IEEE80211_UNSET_POWER_LEVEL;
        wiphy->ht_capa_mod_mask = &mac80211_ht_capa_mod_mask;
        wiphy->vht_capa_mod_mask = &mac80211_vht_capa_mod_mask;

        INIT_LIST_HEAD(&local->interfaces);

        __hw_addr_init(&local->mc_list);

        mutex_init(&local->iflist_mtx);
        mutex_init(&local->mtx);

        mutex_init(&local->key_mtx);
        spin_lock_init(&local->filter_lock);
        spin_lock_init(&local->rx_path_lock);
        spin_lock_init(&local->queue_stop_reason_lock);

        INIT_LIST_HEAD(&local->chanctx_list);
        mutex_init(&local->chanctx_mtx);

        INIT_DELAYED_WORK(&local->scan_work, ieee80211_scan_work);

        INIT_WORK(&local->restart_work, ieee80211_restart_work);

        INIT_WORK(&local->radar_detected_work,
                  ieee80211_dfs_radar_detected_work);

        INIT_WORK(&local->reconfig_filter, ieee80211_reconfig_filter);
        local->smps_mode = IEEE80211_SMPS_OFF;

        INIT_WORK(&local->dynamic_ps_enable_work,
                  ieee80211_dynamic_ps_enable_work);
        INIT_WORK(&local->dynamic_ps_disable_work,
                  ieee80211_dynamic_ps_disable_work);
        setup_timer(&local->dynamic_ps_timer,
                    ieee80211_dynamic_ps_timer, (unsigned long) local);

        INIT_WORK(&local->sched_scan_stopped_work,
                  ieee80211_sched_scan_stopped_work);

        spin_lock_init(&local->ack_status_lock);
        idr_init(&local->ack_status_frames);

        sta_info_init(local);

        for (i = 0; i < IEEE80211_MAX_QUEUES; i++) {
                skb_queue_head_init(&local->pending[i]);
                atomic_set(&local->agg_queue_stop[i], 0);
        }
        tasklet_init(&local->tx_pending_tasklet, ieee80211_tx_pending,
                     (unsigned long)local);

        tasklet_init(&local->tasklet,
                     ieee80211_tasklet_handler,
                     (unsigned long) local);

        skb_queue_head_init(&local->skb_queue);
        skb_queue_head_init(&local->skb_queue_unreliable);

        ieee80211_led_names(local);

        ieee80211_roc_setup(local);

        return &local->hw;
}
EXPORT_SYMBOL(ieee80211_alloc_hw);

int ieee80211_register_hw(struct ieee80211_hw *hw)
{
        struct ieee80211_local *local = hw_to_local(hw);
        int result, i;
        enum ieee80211_band band;
        int channels, max_bitrates;
        bool supp_ht, supp_vht;
        netdev_features_t feature_whitelist;
        struct cfg80211_chan_def dflt_chandef = {};
        static const u32 cipher_suites[] = {
                /* keep WEP first, it may be removed below */
                WLAN_CIPHER_SUITE_WEP40,
                WLAN_CIPHER_SUITE_WEP104,
                WLAN_CIPHER_SUITE_TKIP,
                WLAN_CIPHER_SUITE_CCMP,

                /* keep last -- depends on hw flags! */
                WLAN_CIPHER_SUITE_AES_CMAC
        };

        if (hw->flags & IEEE80211_HW_QUEUE_CONTROL &&
            (local->hw.offchannel_tx_hw_queue == IEEE80211_INVAL_HW_QUEUE ||
             local->hw.offchannel_tx_hw_queue >= local->hw.queues))
                return -EINVAL;

#ifdef CONFIG_PM
        if (hw->wiphy->wowlan && (!local->ops->suspend || !local->ops->resume))
                return -EINVAL;
#endif

        if (!local->use_chanctx) {
                for (i = 0; i < local->hw.wiphy->n_iface_combinations; i++) {
                        const struct ieee80211_iface_combination *comb;

                        comb = &local->hw.wiphy->iface_combinations[i];

                        if (comb->num_different_channels > 1)
                                return -EINVAL;
                }
        } else {
                /*
                 * WDS is currently prohibited when channel contexts are used
                 * because there's no clear definition of which channel WDS
                 * type interfaces use
                 */
                if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_WDS))
                        return -EINVAL;

                /* DFS currently not supported with channel context drivers */
                for (i = 0; i < local->hw.wiphy->n_iface_combinations; i++) {
                        const struct ieee80211_iface_combination *comb;

                        comb = &local->hw.wiphy->iface_combinations[i];

                        if (comb->radar_detect_widths)
                                return -EINVAL;
                }
        }

        /* Only HW csum features are currently compatible with mac80211 */
        feature_whitelist = NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
                            NETIF_F_HW_CSUM;
        if (WARN_ON(hw->netdev_features & ~feature_whitelist))
                return -EINVAL;

        if (hw->max_report_rates == 0)
                hw->max_report_rates = hw->max_rates;

        local->rx_chains = 1;

        /*
         * generic code guarantees at least one band,
         * set this very early because much code assumes
         * that hw.conf.channel is assigned
         */
        channels = 0;
        max_bitrates = 0;
        supp_ht = false;
        supp_vht = false;
        for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
                struct ieee80211_supported_band *sband;

                sband = local->hw.wiphy->bands[band];
                if (!sband)
                        continue;

                if (!dflt_chandef.chan) {
                        cfg80211_chandef_create(&dflt_chandef,
                                                &sband->channels[0],
                                                NL80211_CHAN_NO_HT);
                        /* init channel we're on */
                        if (!local->use_chanctx && !local->_oper_chandef.chan) {
                                local->hw.conf.chandef = dflt_chandef;
                                local->_oper_chandef = dflt_chandef;
                        }
                        local->monitor_chandef = dflt_chandef;
                }

                channels += sband->n_channels;

                if (max_bitrates < sband->n_bitrates)
                        max_bitrates = sband->n_bitrates;
                supp_ht = supp_ht || sband->ht_cap.ht_supported;
                supp_vht = supp_vht || sband->vht_cap.vht_supported;

                if (sband->ht_cap.ht_supported)
                        local->rx_chains =
                                max(ieee80211_mcs_to_chains(&sband->ht_cap.mcs),
                                    local->rx_chains);

                /* TODO: consider VHT for RX chains, hopefully it's the same */
        }

        local->int_scan_req = kzalloc(sizeof(*local->int_scan_req) +
                                      sizeof(void *) * channels, GFP_KERNEL);
        if (!local->int_scan_req)
                return -ENOMEM;

        for (band = 0; band < IEEE80211_NUM_BANDS; band++) {
                if (!local->hw.wiphy->bands[band])
                        continue;
                local->int_scan_req->rates[band] = (u32) -1;
        }

        /* if low-level driver supports AP, we also support VLAN */
        if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_AP)) {
                hw->wiphy->interface_modes |= BIT(NL80211_IFTYPE_AP_VLAN);
                hw->wiphy->software_iftypes |= BIT(NL80211_IFTYPE_AP_VLAN);
        }

        /* mac80211 always supports monitor */
        hw->wiphy->interface_modes |= BIT(NL80211_IFTYPE_MONITOR);
        hw->wiphy->software_iftypes |= BIT(NL80211_IFTYPE_MONITOR);

        /* mac80211 doesn't support more than one IBSS interface right now */
        for (i = 0; i < hw->wiphy->n_iface_combinations; i++) {
                const struct ieee80211_iface_combination *c;
                int j;

                c = &hw->wiphy->iface_combinations[i];

                for (j = 0; j < c->n_limits; j++)
                        if ((c->limits[j].types & BIT(NL80211_IFTYPE_ADHOC)) &&
                            c->limits[j].max > 1)
                                return -EINVAL;
        }

#ifndef CONFIG_MAC80211_MESH
        /* mesh depends on Kconfig, but drivers should set it if they want */
        local->hw.wiphy->interface_modes &= ~BIT(NL80211_IFTYPE_MESH_POINT);
#endif

        /* if the underlying driver supports mesh, mac80211 will (at least)
         * provide routing of mesh authentication frames to userspace */
        if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_MESH_POINT))
                local->hw.wiphy->flags |= WIPHY_FLAG_MESH_AUTH;

        /* mac80211 supports control port protocol changing */
        local->hw.wiphy->flags |= WIPHY_FLAG_CONTROL_PORT_PROTOCOL;

        if (local->hw.flags & IEEE80211_HW_SIGNAL_DBM)
                local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_MBM;
        else if (local->hw.flags & IEEE80211_HW_SIGNAL_UNSPEC)
                local->hw.wiphy->signal_type = CFG80211_SIGNAL_TYPE_UNSPEC;

        WARN((local->hw.flags & IEEE80211_HW_SUPPORTS_UAPSD)
             && (local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK),
             "U-APSD not supported with HW_PS_NULLFUNC_STACK\n");

        /*
         * Calculate scan IE length -- we need this to alloc
         * memory and to subtract from the driver limit. It
         * includes the DS Params, (extended) supported rates, and HT
         * information -- SSID is the driver's responsibility.
         */
        local->scan_ies_len = 4 + max_bitrates /* (ext) supp rates */ +
                3 /* DS Params */;
        if (supp_ht)
                local->scan_ies_len += 2 + sizeof(struct ieee80211_ht_cap);

        if (supp_vht)
                local->scan_ies_len +=
                        2 + sizeof(struct ieee80211_vht_cap);

        if (!local->ops->hw_scan) {
                /* For hw_scan, driver needs to set these up. */
                local->hw.wiphy->max_scan_ssids = 4;
                local->hw.wiphy->max_scan_ie_len = IEEE80211_MAX_DATA_LEN;
        }

        /*
         * If the driver supports any scan IEs, then assume the
         * limit includes the IEs mac80211 will add, otherwise
         * leave it at zero and let the driver sort it out; we
         * still pass our IEs to the driver but userspace will
         * not be allowed to in that case.
         */
        if (local->hw.wiphy->max_scan_ie_len)
                local->hw.wiphy->max_scan_ie_len -= local->scan_ies_len;

        /* Set up cipher suites unless driver already did */
        if (!local->hw.wiphy->cipher_suites) {
                local->hw.wiphy->cipher_suites = cipher_suites;
                local->hw.wiphy->n_cipher_suites = ARRAY_SIZE(cipher_suites);
                if (!(local->hw.flags & IEEE80211_HW_MFP_CAPABLE))
                        local->hw.wiphy->n_cipher_suites--;
        }
        if (IS_ERR(local->wep_tx_tfm) || IS_ERR(local->wep_rx_tfm)) {
                if (local->hw.wiphy->cipher_suites == cipher_suites) {
                        local->hw.wiphy->cipher_suites += 2;
                        local->hw.wiphy->n_cipher_suites -= 2;
                } else {
                        u32 *suites;
                        int r, w = 0;

                        /* Filter out WEP */

                        suites = kmemdup(
                                local->hw.wiphy->cipher_suites,
                                sizeof(u32) * local->hw.wiphy->n_cipher_suites,
                                GFP_KERNEL);
                        if (!suites) {
                                result = -ENOMEM;
                                goto fail_wiphy_register;
                        }
                        for (r = 0; r < local->hw.wiphy->n_cipher_suites; r++) {
                                u32 suite = local->hw.wiphy->cipher_suites[r];
                                if (suite == WLAN_CIPHER_SUITE_WEP40 ||
                                    suite == WLAN_CIPHER_SUITE_WEP104)
                                        continue;
                                suites[w++] = suite;
                        }
                        local->hw.wiphy->cipher_suites = suites;
                        local->hw.wiphy->n_cipher_suites = w;
                        local->wiphy_ciphers_allocated = true;
                }
        }

        if (!local->ops->remain_on_channel)
                local->hw.wiphy->max_remain_on_channel_duration = 5000;

        if (local->ops->sched_scan_start)
                local->hw.wiphy->flags |= WIPHY_FLAG_SUPPORTS_SCHED_SCAN;

        /* mac80211 based drivers don't support internal TDLS setup */
        if (local->hw.wiphy->flags & WIPHY_FLAG_SUPPORTS_TDLS)
                local->hw.wiphy->flags |= WIPHY_FLAG_TDLS_EXTERNAL_SETUP;

        result = wiphy_register(local->hw.wiphy);
        if (result < 0)
                goto fail_wiphy_register;

        /*
         * We use the number of queues for feature tests (QoS, HT) internally
         * so restrict them appropriately.
         */
        if (hw->queues > IEEE80211_MAX_QUEUES)
                hw->queues = IEEE80211_MAX_QUEUES;

        local->workqueue =
                alloc_ordered_workqueue("%s", 0, wiphy_name(local->hw.wiphy));
        if (!local->workqueue) {
                result = -ENOMEM;
                goto fail_workqueue;
        }

        /*
         * The hardware needs headroom for sending the frame,
         * and we need some headroom for passing the frame to monitor
         * interfaces, but never both at the same time.
         */
        local->tx_headroom = max_t(unsigned int , local->hw.extra_tx_headroom,
                                   IEEE80211_TX_STATUS_HEADROOM);

        debugfs_hw_add(local);

        /*
         * if the driver doesn't specify a max listen interval we
         * use 5 which should be a safe default
         */
        if (local->hw.max_listen_interval == 0)
                local->hw.max_listen_interval = 5;

        local->hw.conf.listen_interval = local->hw.max_listen_interval;

        local->dynamic_ps_forced_timeout = -1;

        result = ieee80211_wep_init(local);
        if (result < 0)
                wiphy_debug(local->hw.wiphy, "Failed to initialize wep: %d\n",
                            result);

        ieee80211_led_init(local);

        rtnl_lock();

        result = ieee80211_init_rate_ctrl_alg(local,
                                              hw->rate_control_algorithm);
        if (result < 0) {
                wiphy_debug(local->hw.wiphy,
                            "Failed to initialize rate control algorithm\n");
                goto fail_rate;
        }

        /* add one default STA interface if supported */
        if (local->hw.wiphy->interface_modes & BIT(NL80211_IFTYPE_STATION)) {
                result = ieee80211_if_add(local, "wlan%d", NULL,
                                          NL80211_IFTYPE_STATION, NULL);
                if (result)
                        wiphy_warn(local->hw.wiphy,
                                   "Failed to add default virtual iface\n");
        }

        rtnl_unlock();

        local->network_latency_notifier.notifier_call =
                ieee80211_max_network_latency;
        result = pm_qos_add_notifier(PM_QOS_NETWORK_LATENCY,
                                     &local->network_latency_notifier);
        if (result) {
                rtnl_lock();
                goto fail_pm_qos;
        }

#ifdef CONFIG_INET
        local->ifa_notifier.notifier_call = ieee80211_ifa_changed;
        result = register_inetaddr_notifier(&local->ifa_notifier);
        if (result)
                goto fail_ifa;
#endif

#if IS_ENABLED(CONFIG_IPV6)
        local->ifa6_notifier.notifier_call = ieee80211_ifa6_changed;
        result = register_inet6addr_notifier(&local->ifa6_notifier);
        if (result)
                goto fail_ifa6;
#endif

        return 0;

#if IS_ENABLED(CONFIG_IPV6)
 fail_ifa6:
#ifdef CONFIG_INET
        unregister_inetaddr_notifier(&local->ifa_notifier);
#endif
#endif
#if defined(CONFIG_INET) || defined(CONFIG_IPV6)
 fail_ifa:
        pm_qos_remove_notifier(PM_QOS_NETWORK_LATENCY,
                               &local->network_latency_notifier);
        rtnl_lock();
#endif
 fail_pm_qos:
        ieee80211_led_exit(local);
        ieee80211_remove_interfaces(local);
 fail_rate:
        rtnl_unlock();
        ieee80211_wep_free(local);
        sta_info_stop(local);
        destroy_workqueue(local->workqueue);
 fail_workqueue:
        wiphy_unregister(local->hw.wiphy);
 fail_wiphy_register:
        if (local->wiphy_ciphers_allocated)
                kfree(local->hw.wiphy->cipher_suites);
        kfree(local->int_scan_req);
        return result;
}
EXPORT_SYMBOL(ieee80211_register_hw);

void ieee80211_unregister_hw(struct ieee80211_hw *hw)
{
        struct ieee80211_local *local = hw_to_local(hw);

        tasklet_kill(&local->tx_pending_tasklet);
        tasklet_kill(&local->tasklet);

        pm_qos_remove_notifier(PM_QOS_NETWORK_LATENCY,
                               &local->network_latency_notifier);
#ifdef CONFIG_INET
        unregister_inetaddr_notifier(&local->ifa_notifier);
#endif
#if IS_ENABLED(CONFIG_IPV6)
        unregister_inet6addr_notifier(&local->ifa6_notifier);
#endif

        rtnl_lock();

        /*
         * At this point, interface list manipulations are fine
         * because the driver cannot be handing us frames any
         * more and the tasklet is killed.
         */
        ieee80211_remove_interfaces(local);

        rtnl_unlock();

        cancel_work_sync(&local->restart_work);
        cancel_work_sync(&local->reconfig_filter);

        ieee80211_clear_tx_pending(local);
        rate_control_deinitialize(local);

        if (skb_queue_len(&local->skb_queue) ||
            skb_queue_len(&local->skb_queue_unreliable))
                wiphy_warn(local->hw.wiphy, "skb_queue not empty\n");
        skb_queue_purge(&local->skb_queue);
        skb_queue_purge(&local->skb_queue_unreliable);

        destroy_workqueue(local->workqueue);
        wiphy_unregister(local->hw.wiphy);
        sta_info_stop(local);
        ieee80211_wep_free(local);
        ieee80211_led_exit(local);
        kfree(local->int_scan_req);
}
EXPORT_SYMBOL(ieee80211_unregister_hw);

static int ieee80211_free_ack_frame(int id, void *p, void *data)
{
        WARN_ONCE(1, "Have pending ack frames!\n");
        kfree_skb(p);
        return 0;
}

void ieee80211_free_hw(struct ieee80211_hw *hw)
{
        struct ieee80211_local *local = hw_to_local(hw);

        mutex_destroy(&local->iflist_mtx);
        mutex_destroy(&local->mtx);

        if (local->wiphy_ciphers_allocated)
                kfree(local->hw.wiphy->cipher_suites);

        idr_for_each(&local->ack_status_frames,
                     ieee80211_free_ack_frame, NULL);
        idr_destroy(&local->ack_status_frames);

        wiphy_free(local->hw.wiphy);
}
EXPORT_SYMBOL(ieee80211_free_hw);

static int __init ieee80211_init(void)
{
        struct sk_buff *skb;
        int ret;

        BUILD_BUG_ON(sizeof(struct ieee80211_tx_info) > sizeof(skb->cb));
        BUILD_BUG_ON(offsetof(struct ieee80211_tx_info, driver_data) +
                     IEEE80211_TX_INFO_DRIVER_DATA_SIZE > sizeof(skb->cb));

        ret = rc80211_minstrel_init();
        if (ret)
                return ret;

        ret = rc80211_minstrel_ht_init();
        if (ret)
                goto err_minstrel;

        ret = rc80211_pid_init();
        if (ret)
                goto err_pid;

        ret = ieee80211_iface_init();
        if (ret)
                goto err_netdev;

        return 0;
 err_netdev:
        rc80211_pid_exit();
 err_pid:
        rc80211_minstrel_ht_exit();
 err_minstrel:
        rc80211_minstrel_exit();

        return ret;
}

static void __exit ieee80211_exit(void)
{
        rc80211_pid_exit();
        rc80211_minstrel_ht_exit();
        rc80211_minstrel_exit();

        ieee80211s_stop();

        ieee80211_iface_exit();

        rcu_barrier();
}


subsys_initcall(ieee80211_init);
module_exit(ieee80211_exit);

MODULE_DESCRIPTION("IEEE 802.11 subsystem");
MODULE_LICENSE("GPL");