litmus-rt.git - The LITMUS^RT kernel.

/*
 * BSS client mode implementation
 * Copyright 2003-2008, Jouni Malinen <j@w1.fi>
 * Copyright 2004, Instant802 Networks, Inc.
 * Copyright 2005, Devicescape Software, Inc.
 * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
 * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
 * Copyright 2013-2014  Intel Mobile Communications GmbH
 * Copyright (C) 2015 - 2016 Intel Deutschland GmbH
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/delay.h>
#include <linux/if_ether.h>
#include <linux/skbuff.h>
#include <linux/if_arp.h>
#include <linux/etherdevice.h>
#include <linux/moduleparam.h>
#include <linux/rtnetlink.h>
#include <linux/crc32.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <net/mac80211.h>
#include <asm/unaligned.h>

#include "ieee80211_i.h"
#include "driver-ops.h"
#include "rate.h"
#include "led.h"

#define IEEE80211_AUTH_TIMEOUT		(HZ / 5)
#define IEEE80211_AUTH_TIMEOUT_LONG	(HZ / 2)
#define IEEE80211_AUTH_TIMEOUT_SHORT	(HZ / 10)
#define IEEE80211_AUTH_MAX_TRIES	3
#define IEEE80211_AUTH_WAIT_ASSOC	(HZ * 5)
#define IEEE80211_ASSOC_TIMEOUT		(HZ / 5)
#define IEEE80211_ASSOC_TIMEOUT_LONG	(HZ / 2)
#define IEEE80211_ASSOC_TIMEOUT_SHORT	(HZ / 10)
#define IEEE80211_ASSOC_MAX_TRIES	3

static int max_nullfunc_tries = 2;
module_param(max_nullfunc_tries, int, 0644);
MODULE_PARM_DESC(max_nullfunc_tries,
		 "Maximum nullfunc tx tries before disconnecting (reason 4).");

static int max_probe_tries = 5;
module_param(max_probe_tries, int, 0644);
MODULE_PARM_DESC(max_probe_tries,
		 "Maximum probe tries before disconnecting (reason 4).");

/*
 * Beacon loss timeout is calculated as N frames times the
 * advertised beacon interval.  This may need to be somewhat
 * higher than what hardware might detect to account for
 * delays in the host processing frames. But since we also
 * probe on beacon miss before declaring the connection lost
 * default to what we want.
 */
static int beacon_loss_count = 7;
module_param(beacon_loss_count, int, 0644);
MODULE_PARM_DESC(beacon_loss_count,
		 "Number of beacon intervals before we decide beacon was lost.");

/*
 * Time the connection can be idle before we probe
 * it to see if we can still talk to the AP.
 */
#define IEEE80211_CONNECTION_IDLE_TIME	(30 * HZ)
/*
 * Time we wait for a probe response after sending
 * a probe request because of beacon loss or for
 * checking the connection still works.
 */
static int probe_wait_ms = 500;
module_param(probe_wait_ms, int, 0644);
MODULE_PARM_DESC(probe_wait_ms,
		 "Maximum time(ms) to wait for probe response"
		 " before disconnecting (reason 4).");

/*
 * How many Beacon frames need to have been used in average signal strength
 * before starting to indicate signal change events.
 */
#define IEEE80211_SIGNAL_AVE_MIN_COUNT	4

/*
 * We can have multiple work items (and connection probing)
 * scheduling this timer, but we need to take care to only
 * reschedule it when it should fire _earlier_ than it was
 * asked for before, or if it's not pending right now. This
 * function ensures that. Note that it then is required to
 * run this function for all timeouts after the first one
 * has happened -- the work that runs from this timer will
 * do that.
 */
static void run_again(struct ieee80211_sub_if_data *sdata,
		      unsigned long timeout)
{
	sdata_assert_lock(sdata);

	if (!timer_pending(&sdata->u.mgd.timer) ||
	    time_before(timeout, sdata->u.mgd.timer.expires))
		mod_timer(&sdata->u.mgd.timer, timeout);
}

void ieee80211_sta_reset_beacon_monitor(struct ieee80211_sub_if_data *sdata)
{
	if (sdata->vif.driver_flags & IEEE80211_VIF_BEACON_FILTER)
		return;

	if (ieee80211_hw_check(&sdata->local->hw, CONNECTION_MONITOR))
		return;

	mod_timer(&sdata->u.mgd.bcn_mon_timer,
		  round_jiffies_up(jiffies + sdata->u.mgd.beacon_timeout));
}

void ieee80211_sta_reset_conn_monitor(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;

	if (unlikely(!sdata->u.mgd.associated))
		return;

	ifmgd->probe_send_count = 0;

	if (ieee80211_hw_check(&sdata->local->hw, CONNECTION_MONITOR))
		return;

	mod_timer(&sdata->u.mgd.conn_mon_timer,
		  round_jiffies_up(jiffies + IEEE80211_CONNECTION_IDLE_TIME));
}

static int ecw2cw(int ecw)
{
	return (1 << ecw) - 1;
}

static u32
ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
			     struct ieee80211_supported_band *sband,
			     struct ieee80211_channel *channel,
			     const struct ieee80211_ht_cap *ht_cap,
			     const struct ieee80211_ht_operation *ht_oper,
			     const struct ieee80211_vht_operation *vht_oper,
			     struct cfg80211_chan_def *chandef, bool tracking)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	struct cfg80211_chan_def vht_chandef;
	struct ieee80211_sta_ht_cap sta_ht_cap;
	u32 ht_cfreq, ret;

	memcpy(&sta_ht_cap, &sband->ht_cap, sizeof(sta_ht_cap));
	ieee80211_apply_htcap_overrides(sdata, &sta_ht_cap);

	chandef->chan = channel;
	chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
	chandef->center_freq1 = channel->center_freq;
	chandef->center_freq2 = 0;

	if (!ht_cap || !ht_oper || !sta_ht_cap.ht_supported) {
		ret = IEEE80211_STA_DISABLE_HT | IEEE80211_STA_DISABLE_VHT;
		goto out;
	}

	chandef->width = NL80211_CHAN_WIDTH_20;

	if (!(ht_cap->cap_info &
	      cpu_to_le16(IEEE80211_HT_CAP_SUP_WIDTH_20_40))) {
		ret = IEEE80211_STA_DISABLE_40MHZ;
		vht_chandef = *chandef;
		goto out;
	}

	ht_cfreq = ieee80211_channel_to_frequency(ht_oper->primary_chan,
						  channel->band);
	/* check that channel matches the right operating channel */
	if (!tracking && channel->center_freq != ht_cfreq) {
		/*
		 * It's possible that some APs are confused here;
		 * Netgear WNDR3700 sometimes reports 4 higher than
		 * the actual channel in association responses, but
		 * since we look at probe response/beacon data here
		 * it should be OK.
		 */
		sdata_info(sdata,
			   "Wrong control channel: center-freq: %d ht-cfreq: %d ht->primary_chan: %d band: %d - Disabling HT\n",
			   channel->center_freq, ht_cfreq,
			   ht_oper->primary_chan, channel->band);
		ret = IEEE80211_STA_DISABLE_HT | IEEE80211_STA_DISABLE_VHT;
		goto out;
	}

	/* check 40 MHz support, if we have it */
	if (sta_ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) {
		ieee80211_chandef_ht_oper(ht_oper, chandef);
	} else {
		/* 40 MHz (and 80 MHz) must be supported for VHT */
		ret = IEEE80211_STA_DISABLE_VHT;
		/* also mark 40 MHz disabled */
		ret |= IEEE80211_STA_DISABLE_40MHZ;
		goto out;
	}

	if (!vht_oper || !sband->vht_cap.vht_supported) {
		ret = IEEE80211_STA_DISABLE_VHT;
		goto out;
	}

	vht_chandef = *chandef;
	if (!ieee80211_chandef_vht_oper(vht_oper, &vht_chandef)) {
		if (!(ifmgd->flags & IEEE80211_STA_DISABLE_VHT))
			sdata_info(sdata,
				   "AP VHT information is invalid, disable VHT\n");
		ret = IEEE80211_STA_DISABLE_VHT;
		goto out;
	}

	if (!cfg80211_chandef_valid(&vht_chandef)) {
		if (!(ifmgd->flags & IEEE80211_STA_DISABLE_VHT))
			sdata_info(sdata,
				   "AP VHT information is invalid, disable VHT\n");
		ret = IEEE80211_STA_DISABLE_VHT;
		goto out;
	}

	if (cfg80211_chandef_identical(chandef, &vht_chandef)) {
		ret = 0;
		goto out;
	}

	if (!cfg80211_chandef_compatible(chandef, &vht_chandef)) {
		if (!(ifmgd->flags & IEEE80211_STA_DISABLE_VHT))
			sdata_info(sdata,
				   "AP VHT information doesn't match HT, disable VHT\n");
		ret = IEEE80211_STA_DISABLE_VHT;
		goto out;
	}

	*chandef = vht_chandef;

	ret = 0;

out:
	/*
	 * When tracking the current AP, don't do any further checks if the
	 * new chandef is identical to the one we're currently using for the
	 * connection. This keeps us from playing ping-pong with regulatory,
	 * without it the following can happen (for example):
	 *  - connect to an AP with 80 MHz, world regdom allows 80 MHz
	 *  - AP advertises regdom US
	 *  - CRDA loads regdom US with 80 MHz prohibited (old database)
	 *  - the code below detects an unsupported channel, downgrades, and
	 *    we disconnect from the AP in the caller
	 *  - disconnect causes CRDA to reload world regdomain and the game
	 *    starts anew.
	 * (see https://bugzilla.kernel.org/show_bug.cgi?id=70881)
	 *
	 * It seems possible that there are still scenarios with CSA or real
	 * bandwidth changes where a this could happen, but those cases are
	 * less common and wouldn't completely prevent using the AP.
	 */
	if (tracking &&
	    cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef))
		return ret;

	/* don't print the message below for VHT mismatch if VHT is disabled */
	if (ret & IEEE80211_STA_DISABLE_VHT)
		vht_chandef = *chandef;

	/*
	 * Ignore the DISABLED flag when we're already connected and only
	 * tracking the APs beacon for bandwidth changes - otherwise we
	 * might get disconnected here if we connect to an AP, update our
	 * regulatory information based on the AP's country IE and the
	 * information we have is wrong/outdated and disables the channel
	 * that we're actually using for the connection to the AP.
	 */
	while (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef,
					tracking ? 0 :
						   IEEE80211_CHAN_DISABLED)) {
		if (WARN_ON(chandef->width == NL80211_CHAN_WIDTH_20_NOHT)) {
			ret = IEEE80211_STA_DISABLE_HT |
			      IEEE80211_STA_DISABLE_VHT;
			break;
		}

		ret |= ieee80211_chandef_downgrade(chandef);
	}

	if (chandef->width != vht_chandef.width && !tracking)
		sdata_info(sdata,
			   "capabilities/regulatory prevented using AP HT/VHT configuration, downgraded\n");

	WARN_ON_ONCE(!cfg80211_chandef_valid(chandef));
	return ret;
}

static int ieee80211_config_bw(struct ieee80211_sub_if_data *sdata,
			       struct sta_info *sta,
			       const struct ieee80211_ht_cap *ht_cap,
			       const struct ieee80211_ht_operation *ht_oper,
			       const struct ieee80211_vht_operation *vht_oper,
			       const u8 *bssid, u32 *changed)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	struct ieee80211_supported_band *sband;
	struct ieee80211_channel *chan;
	struct cfg80211_chan_def chandef;
	u16 ht_opmode;
	u32 flags;
	enum ieee80211_sta_rx_bandwidth new_sta_bw;
	int ret;

	/* if HT was/is disabled, don't track any bandwidth changes */
	if (ifmgd->flags & IEEE80211_STA_DISABLE_HT || !ht_oper)
		return 0;

	/* don't check VHT if we associated as non-VHT station */
	if (ifmgd->flags & IEEE80211_STA_DISABLE_VHT)
		vht_oper = NULL;

	if (WARN_ON_ONCE(!sta))
		return -EINVAL;

	/*
	 * if bss configuration changed store the new one -
	 * this may be applicable even if channel is identical
	 */
	ht_opmode = le16_to_cpu(ht_oper->operation_mode);
	if (sdata->vif.bss_conf.ht_operation_mode != ht_opmode) {
		*changed |= BSS_CHANGED_HT;
		sdata->vif.bss_conf.ht_operation_mode = ht_opmode;
	}

	chan = sdata->vif.bss_conf.chandef.chan;
	sband = local->hw.wiphy->bands[chan->band];

	/* calculate new channel (type) based on HT/VHT operation IEs */
	flags = ieee80211_determine_chantype(sdata, sband, chan,
					     ht_cap, ht_oper, vht_oper,
					     &chandef, true);

	/*
	 * Downgrade the new channel if we associated with restricted
	 * capabilities. For example, if we associated as a 20 MHz STA
	 * to a 40 MHz AP (due to regulatory, capabilities or config
	 * reasons) then switching to a 40 MHz channel now won't do us
	 * any good -- we couldn't use it with the AP.
	 */
	if (ifmgd->flags & IEEE80211_STA_DISABLE_80P80MHZ &&
	    chandef.width == NL80211_CHAN_WIDTH_80P80)
		flags |= ieee80211_chandef_downgrade(&chandef);
	if (ifmgd->flags & IEEE80211_STA_DISABLE_160MHZ &&
	    chandef.width == NL80211_CHAN_WIDTH_160)
		flags |= ieee80211_chandef_downgrade(&chandef);
	if (ifmgd->flags & IEEE80211_STA_DISABLE_40MHZ &&
	    chandef.width > NL80211_CHAN_WIDTH_20)
		flags |= ieee80211_chandef_downgrade(&chandef);

	if (cfg80211_chandef_identical(&chandef, &sdata->vif.bss_conf.chandef))
		return 0;

	sdata_info(sdata,
		   "AP %pM changed bandwidth, new config is %d MHz, width %d (%d/%d MHz)\n",
		   ifmgd->bssid, chandef.chan->center_freq, chandef.width,
		   chandef.center_freq1, chandef.center_freq2);

	if (flags != (ifmgd->flags & (IEEE80211_STA_DISABLE_HT |
				      IEEE80211_STA_DISABLE_VHT |
				      IEEE80211_STA_DISABLE_40MHZ |
				      IEEE80211_STA_DISABLE_80P80MHZ |
				      IEEE80211_STA_DISABLE_160MHZ)) ||
	    !cfg80211_chandef_valid(&chandef)) {
		sdata_info(sdata,
			   "AP %pM changed bandwidth in a way we can't support - disconnect\n",
			   ifmgd->bssid);
		return -EINVAL;
	}

	switch (chandef.width) {
	case NL80211_CHAN_WIDTH_20_NOHT:
	case NL80211_CHAN_WIDTH_20:
		new_sta_bw = IEEE80211_STA_RX_BW_20;
		break;
	case NL80211_CHAN_WIDTH_40:
		new_sta_bw = IEEE80211_STA_RX_BW_40;
		break;
	case NL80211_CHAN_WIDTH_80:
		new_sta_bw = IEEE80211_STA_RX_BW_80;
		break;
	case NL80211_CHAN_WIDTH_80P80:
	case NL80211_CHAN_WIDTH_160:
		new_sta_bw = IEEE80211_STA_RX_BW_160;
		break;
	default:
		return -EINVAL;
	}

	if (new_sta_bw > sta->cur_max_bandwidth)
		new_sta_bw = sta->cur_max_bandwidth;

	if (new_sta_bw < sta->sta.bandwidth) {
		sta->sta.bandwidth = new_sta_bw;
		rate_control_rate_update(local, sband, sta,
					 IEEE80211_RC_BW_CHANGED);
	}

	ret = ieee80211_vif_change_bandwidth(sdata, &chandef, changed);
	if (ret) {
		sdata_info(sdata,
			   "AP %pM changed bandwidth to incompatible one - disconnect\n",
			   ifmgd->bssid);
		return ret;
	}

	if (new_sta_bw > sta->sta.bandwidth) {
		sta->sta.bandwidth = new_sta_bw;
		rate_control_rate_update(local, sband, sta,
					 IEEE80211_RC_BW_CHANGED);
	}

	return 0;
}

/* frame sending functions */

static void ieee80211_add_ht_ie(struct ieee80211_sub_if_data *sdata,
				struct sk_buff *skb, u8 ap_ht_param,
				struct ieee80211_supported_band *sband,
				struct ieee80211_channel *channel,
				enum ieee80211_smps_mode smps)
{
	u8 *pos;
	u32 flags = channel->flags;
	u16 cap;
	struct ieee80211_sta_ht_cap ht_cap;

	BUILD_BUG_ON(sizeof(ht_cap) != sizeof(sband->ht_cap));

	memcpy(&ht_cap, &sband->ht_cap, sizeof(ht_cap));
	ieee80211_apply_htcap_overrides(sdata, &ht_cap);

	/* determine capability flags */
	cap = ht_cap.cap;

	switch (ap_ht_param & IEEE80211_HT_PARAM_CHA_SEC_OFFSET) {
	case IEEE80211_HT_PARAM_CHA_SEC_ABOVE:
		if (flags & IEEE80211_CHAN_NO_HT40PLUS) {
			cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
			cap &= ~IEEE80211_HT_CAP_SGI_40;
		}
		break;
	case IEEE80211_HT_PARAM_CHA_SEC_BELOW:
		if (flags & IEEE80211_CHAN_NO_HT40MINUS) {
			cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
			cap &= ~IEEE80211_HT_CAP_SGI_40;
		}
		break;
	}

	/*
	 * If 40 MHz was disabled associate as though we weren't
	 * capable of 40 MHz -- some broken APs will never fall
	 * back to trying to transmit in 20 MHz.
	 */
	if (sdata->u.mgd.flags & IEEE80211_STA_DISABLE_40MHZ) {
		cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40;
		cap &= ~IEEE80211_HT_CAP_SGI_40;
	}

	/* set SM PS mode properly */
	cap &= ~IEEE80211_HT_CAP_SM_PS;
	switch (smps) {
	case IEEE80211_SMPS_AUTOMATIC:
	case IEEE80211_SMPS_NUM_MODES:
		WARN_ON(1);
	case IEEE80211_SMPS_OFF:
		cap |= WLAN_HT_CAP_SM_PS_DISABLED <<
			IEEE80211_HT_CAP_SM_PS_SHIFT;
		break;
	case IEEE80211_SMPS_STATIC:
		cap |= WLAN_HT_CAP_SM_PS_STATIC <<
			IEEE80211_HT_CAP_SM_PS_SHIFT;
		break;
	case IEEE80211_SMPS_DYNAMIC:
		cap |= WLAN_HT_CAP_SM_PS_DYNAMIC <<
			IEEE80211_HT_CAP_SM_PS_SHIFT;
		break;
	}

	/* reserve and fill IE */
	pos = skb_put(skb, sizeof(struct ieee80211_ht_cap) + 2);
	ieee80211_ie_build_ht_cap(pos, &ht_cap, cap);
}

/* This function determines vht capability flags for the association
 * and builds the IE.
 * Note - the function may set the owner of the MU-MIMO capability
 */
static void ieee80211_add_vht_ie(struct ieee80211_sub_if_data *sdata,
				 struct sk_buff *skb,
				 struct ieee80211_supported_band *sband,
				 struct ieee80211_vht_cap *ap_vht_cap)
{
	struct ieee80211_local *local = sdata->local;
	u8 *pos;
	u32 cap;
	struct ieee80211_sta_vht_cap vht_cap;
	u32 mask, ap_bf_sts, our_bf_sts;

	BUILD_BUG_ON(sizeof(vht_cap) != sizeof(sband->vht_cap));

	memcpy(&vht_cap, &sband->vht_cap, sizeof(vht_cap));
	ieee80211_apply_vhtcap_overrides(sdata, &vht_cap);

	/* determine capability flags */
	cap = vht_cap.cap;

	if (sdata->u.mgd.flags & IEEE80211_STA_DISABLE_80P80MHZ) {
		u32 bw = cap & IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;

		cap &= ~IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
		if (bw == IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ ||
		    bw == IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160_80PLUS80MHZ)
			cap |= IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ;
	}

	if (sdata->u.mgd.flags & IEEE80211_STA_DISABLE_160MHZ) {
		cap &= ~IEEE80211_VHT_CAP_SHORT_GI_160;
		cap &= ~IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_MASK;
	}

	/*
	 * Some APs apparently get confused if our capabilities are better
	 * than theirs, so restrict what we advertise in the assoc request.
	 */
	if (!(ap_vht_cap->vht_cap_info &
			cpu_to_le32(IEEE80211_VHT_CAP_SU_BEAMFORMER_CAPABLE)))
		cap &= ~(IEEE80211_VHT_CAP_SU_BEAMFORMEE_CAPABLE |
			 IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE);
	else if (!(ap_vht_cap->vht_cap_info &
			cpu_to_le32(IEEE80211_VHT_CAP_MU_BEAMFORMER_CAPABLE)))
		cap &= ~IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE;

	/*
	 * If some other vif is using the MU-MIMO capablity we cannot associate
	 * using MU-MIMO - this will lead to contradictions in the group-id
	 * mechanism.
	 * Ownership is defined since association request, in order to avoid
	 * simultaneous associations with MU-MIMO.
	 */
	if (cap & IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE) {
		bool disable_mu_mimo = false;
		struct ieee80211_sub_if_data *other;

		list_for_each_entry_rcu(other, &local->interfaces, list) {
			if (other->vif.mu_mimo_owner) {
				disable_mu_mimo = true;
				break;
			}
		}
		if (disable_mu_mimo)
			cap &= ~IEEE80211_VHT_CAP_MU_BEAMFORMEE_CAPABLE;
		else
			sdata->vif.mu_mimo_owner = true;
	}

	mask = IEEE80211_VHT_CAP_BEAMFORMEE_STS_MASK;

	ap_bf_sts = le32_to_cpu(ap_vht_cap->vht_cap_info) & mask;
	our_bf_sts = cap & mask;

	if (ap_bf_sts < our_bf_sts) {
		cap &= ~mask;
		cap |= ap_bf_sts;
	}

	/* reserve and fill IE */
	pos = skb_put(skb, sizeof(struct ieee80211_vht_cap) + 2);
	ieee80211_ie_build_vht_cap(pos, &vht_cap, cap);
}

static void ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	struct ieee80211_mgd_assoc_data *assoc_data = ifmgd->assoc_data;
	struct sk_buff *skb;
	struct ieee80211_mgmt *mgmt;
	u8 *pos, qos_info;
	size_t offset = 0, noffset;
	int i, count, rates_len, supp_rates_len, shift;
	u16 capab;
	struct ieee80211_supported_band *sband;
	struct ieee80211_chanctx_conf *chanctx_conf;
	struct ieee80211_channel *chan;
	u32 rate_flags, rates = 0;

	sdata_assert_lock(sdata);

	rcu_read_lock();
	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
	if (WARN_ON(!chanctx_conf)) {
		rcu_read_unlock();
		return;
	}
	chan = chanctx_conf->def.chan;
	rate_flags = ieee80211_chandef_rate_flags(&chanctx_conf->def);
	rcu_read_unlock();
	sband = local->hw.wiphy->bands[chan->band];
	shift = ieee80211_vif_get_shift(&sdata->vif);

	if (assoc_data->supp_rates_len) {
		/*
		 * Get all rates supported by the device and the AP as
		 * some APs don't like getting a superset of their rates
		 * in the association request (e.g. D-Link DAP 1353 in
		 * b-only mode)...
		 */
		rates_len = ieee80211_parse_bitrates(&chanctx_conf->def, sband,
						     assoc_data->supp_rates,
						     assoc_data->supp_rates_len,
						     &rates);
	} else {
		/*
		 * In case AP not provide any supported rates information
		 * before association, we send information element(s) with
		 * all rates that we support.
		 */
		rates_len = 0;
		for (i = 0; i < sband->n_bitrates; i++) {
			if ((rate_flags & sband->bitrates[i].flags)
			    != rate_flags)
				continue;
			rates |= BIT(i);
			rates_len++;
		}
	}

	skb = alloc_skb(local->hw.extra_tx_headroom +
			sizeof(*mgmt) + /* bit too much but doesn't matter */
			2 + assoc_data->ssid_len + /* SSID */
			4 + rates_len + /* (extended) rates */
			4 + /* power capability */
			2 + 2 * sband->n_channels + /* supported channels */
			2 + sizeof(struct ieee80211_ht_cap) + /* HT */
			2 + sizeof(struct ieee80211_vht_cap) + /* VHT */
			assoc_data->ie_len + /* extra IEs */
			9, /* WMM */
			GFP_KERNEL);
	if (!skb)
		return;

	skb_reserve(skb, local->hw.extra_tx_headroom);

	capab = WLAN_CAPABILITY_ESS;

	if (sband->band == IEEE80211_BAND_2GHZ) {
		capab |= WLAN_CAPABILITY_SHORT_SLOT_TIME;
		capab |= WLAN_CAPABILITY_SHORT_PREAMBLE;
	}

	if (assoc_data->capability & WLAN_CAPABILITY_PRIVACY)
		capab |= WLAN_CAPABILITY_PRIVACY;

	if ((assoc_data->capability & WLAN_CAPABILITY_SPECTRUM_MGMT) &&
	    ieee80211_hw_check(&local->hw, SPECTRUM_MGMT))
		capab |= WLAN_CAPABILITY_SPECTRUM_MGMT;

	if (ifmgd->flags & IEEE80211_STA_ENABLE_RRM)
		capab |= WLAN_CAPABILITY_RADIO_MEASURE;

	mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
	memset(mgmt, 0, 24);
	memcpy(mgmt->da, assoc_data->bss->bssid, ETH_ALEN);
	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
	memcpy(mgmt->bssid, assoc_data->bss->bssid, ETH_ALEN);

	if (!is_zero_ether_addr(assoc_data->prev_bssid)) {
		skb_put(skb, 10);
		mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
						  IEEE80211_STYPE_REASSOC_REQ);
		mgmt->u.reassoc_req.capab_info = cpu_to_le16(capab);
		mgmt->u.reassoc_req.listen_interval =
				cpu_to_le16(local->hw.conf.listen_interval);
		memcpy(mgmt->u.reassoc_req.current_ap, assoc_data->prev_bssid,
		       ETH_ALEN);
	} else {
		skb_put(skb, 4);
		mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
						  IEEE80211_STYPE_ASSOC_REQ);
		mgmt->u.assoc_req.capab_info = cpu_to_le16(capab);
		mgmt->u.assoc_req.listen_interval =
				cpu_to_le16(local->hw.conf.listen_interval);
	}

	/* SSID */
	pos = skb_put(skb, 2 + assoc_data->ssid_len);
	*pos++ = WLAN_EID_SSID;
	*pos++ = assoc_data->ssid_len;
	memcpy(pos, assoc_data->ssid, assoc_data->ssid_len);

	/* add all rates which were marked to be used above */
	supp_rates_len = rates_len;
	if (supp_rates_len > 8)
		supp_rates_len = 8;

	pos = skb_put(skb, supp_rates_len + 2);
	*pos++ = WLAN_EID_SUPP_RATES;
	*pos++ = supp_rates_len;

	count = 0;
	for (i = 0; i < sband->n_bitrates; i++) {
		if (BIT(i) & rates) {
			int rate = DIV_ROUND_UP(sband->bitrates[i].bitrate,
						5 * (1 << shift));
			*pos++ = (u8) rate;
			if (++count == 8)
				break;
		}
	}

	if (rates_len > count) {
		pos = skb_put(skb, rates_len - count + 2);
		*pos++ = WLAN_EID_EXT_SUPP_RATES;
		*pos++ = rates_len - count;

		for (i++; i < sband->n_bitrates; i++) {
			if (BIT(i) & rates) {
				int rate;
				rate = DIV_ROUND_UP(sband->bitrates[i].bitrate,
						    5 * (1 << shift));
				*pos++ = (u8) rate;
			}
		}
	}

	if (capab & WLAN_CAPABILITY_SPECTRUM_MGMT ||
	    capab & WLAN_CAPABILITY_RADIO_MEASURE) {
		pos = skb_put(skb, 4);
		*pos++ = WLAN_EID_PWR_CAPABILITY;
		*pos++ = 2;
		*pos++ = 0; /* min tx power */
		 /* max tx power */
		*pos++ = ieee80211_chandef_max_power(&chanctx_conf->def);
	}

	if (capab & WLAN_CAPABILITY_SPECTRUM_MGMT) {
		/* TODO: get this in reg domain format */
		pos = skb_put(skb, 2 * sband->n_channels + 2);
		*pos++ = WLAN_EID_SUPPORTED_CHANNELS;
		*pos++ = 2 * sband->n_channels;
		for (i = 0; i < sband->n_channels; i++) {
			*pos++ = ieee80211_frequency_to_channel(
					sband->channels[i].center_freq);
			*pos++ = 1; /* one channel in the subband*/
		}
	}

	/* if present, add any custom IEs that go before HT */
	if (assoc_data->ie_len) {
		static const u8 before_ht[] = {
			WLAN_EID_SSID,
			WLAN_EID_SUPP_RATES,
			WLAN_EID_EXT_SUPP_RATES,
			WLAN_EID_PWR_CAPABILITY,
			WLAN_EID_SUPPORTED_CHANNELS,
			WLAN_EID_RSN,
			WLAN_EID_QOS_CAPA,
			WLAN_EID_RRM_ENABLED_CAPABILITIES,
			WLAN_EID_MOBILITY_DOMAIN,
			WLAN_EID_FAST_BSS_TRANSITION,	/* reassoc only */
			WLAN_EID_RIC_DATA,		/* reassoc only */
			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
		};
		static const u8 after_ric[] = {
			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
			WLAN_EID_HT_CAPABILITY,
			WLAN_EID_BSS_COEX_2040,
			WLAN_EID_EXT_CAPABILITY,
			WLAN_EID_QOS_TRAFFIC_CAPA,
			WLAN_EID_TIM_BCAST_REQ,
			WLAN_EID_INTERWORKING,
			/* 60GHz doesn't happen right now */
			WLAN_EID_VHT_CAPABILITY,
			WLAN_EID_OPMODE_NOTIF,
		};

		noffset = ieee80211_ie_split_ric(assoc_data->ie,
						 assoc_data->ie_len,
						 before_ht,
						 ARRAY_SIZE(before_ht),
						 after_ric,
						 ARRAY_SIZE(after_ric),
						 offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, assoc_data->ie + offset, noffset - offset);
		offset = noffset;
	}

	if (WARN_ON_ONCE((ifmgd->flags & IEEE80211_STA_DISABLE_HT) &&
			 !(ifmgd->flags & IEEE80211_STA_DISABLE_VHT)))
		ifmgd->flags |= IEEE80211_STA_DISABLE_VHT;

	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT))
		ieee80211_add_ht_ie(sdata, skb, assoc_data->ap_ht_param,
				    sband, chan, sdata->smps_mode);

	/* if present, add any custom IEs that go before VHT */
	if (assoc_data->ie_len) {
		static const u8 before_vht[] = {
			WLAN_EID_SSID,
			WLAN_EID_SUPP_RATES,
			WLAN_EID_EXT_SUPP_RATES,
			WLAN_EID_PWR_CAPABILITY,
			WLAN_EID_SUPPORTED_CHANNELS,
			WLAN_EID_RSN,
			WLAN_EID_QOS_CAPA,
			WLAN_EID_RRM_ENABLED_CAPABILITIES,
			WLAN_EID_MOBILITY_DOMAIN,
			WLAN_EID_SUPPORTED_REGULATORY_CLASSES,
			WLAN_EID_HT_CAPABILITY,
			WLAN_EID_BSS_COEX_2040,
			WLAN_EID_EXT_CAPABILITY,
			WLAN_EID_QOS_TRAFFIC_CAPA,
			WLAN_EID_TIM_BCAST_REQ,
			WLAN_EID_INTERWORKING,
		};

		/* RIC already taken above, so no need to handle here anymore */
		noffset = ieee80211_ie_split(assoc_data->ie, assoc_data->ie_len,
					     before_vht, ARRAY_SIZE(before_vht),
					     offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, assoc_data->ie + offset, noffset - offset);
		offset = noffset;
	}

	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_VHT))
		ieee80211_add_vht_ie(sdata, skb, sband,
				     &assoc_data->ap_vht_cap);

	/* if present, add any custom non-vendor IEs that go after HT */
	if (assoc_data->ie_len) {
		noffset = ieee80211_ie_split_vendor(assoc_data->ie,
						    assoc_data->ie_len,
						    offset);
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, assoc_data->ie + offset, noffset - offset);
		offset = noffset;
	}

	if (assoc_data->wmm) {
		if (assoc_data->uapsd) {
			qos_info = ifmgd->uapsd_queues;
			qos_info |= (ifmgd->uapsd_max_sp_len <<
				     IEEE80211_WMM_IE_STA_QOSINFO_SP_SHIFT);
		} else {
			qos_info = 0;
		}

		pos = ieee80211_add_wmm_info_ie(skb_put(skb, 9), qos_info);
	}

	/* add any remaining custom (i.e. vendor specific here) IEs */
	if (assoc_data->ie_len) {
		noffset = assoc_data->ie_len;
		pos = skb_put(skb, noffset - offset);
		memcpy(pos, assoc_data->ie + offset, noffset - offset);
	}

	drv_mgd_prepare_tx(local, sdata);

	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
	if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS |
						IEEE80211_TX_INTFL_MLME_CONN_TX;
	ieee80211_tx_skb(sdata, skb);
}

void ieee80211_send_pspoll(struct ieee80211_local *local,
			   struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_pspoll *pspoll;
	struct sk_buff *skb;

	skb = ieee80211_pspoll_get(&local->hw, &sdata->vif);
	if (!skb)
		return;

	pspoll = (struct ieee80211_pspoll *) skb->data;
	pspoll->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);

	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
	ieee80211_tx_skb(sdata, skb);
}

void ieee80211_send_nullfunc(struct ieee80211_local *local,
			     struct ieee80211_sub_if_data *sdata,
			     bool powersave)
{
	struct sk_buff *skb;
	struct ieee80211_hdr_3addr *nullfunc;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;

	skb = ieee80211_nullfunc_get(&local->hw, &sdata->vif);
	if (!skb)
		return;

	nullfunc = (struct ieee80211_hdr_3addr *) skb->data;
	if (powersave)
		nullfunc->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);

	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT |
					IEEE80211_TX_INTFL_OFFCHAN_TX_OK;

	if (ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;

	if (ifmgd->flags & IEEE80211_STA_CONNECTION_POLL)
		IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_USE_MINRATE;

	ieee80211_tx_skb(sdata, skb);
}

static void ieee80211_send_4addr_nullfunc(struct ieee80211_local *local,
					  struct ieee80211_sub_if_data *sdata)
{
	struct sk_buff *skb;
	struct ieee80211_hdr *nullfunc;
	__le16 fc;

	if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_STATION))
		return;

	skb = dev_alloc_skb(local->hw.extra_tx_headroom + 30);
	if (!skb)
		return;

	skb_reserve(skb, local->hw.extra_tx_headroom);

	nullfunc = (struct ieee80211_hdr *) skb_put(skb, 30);
	memset(nullfunc, 0, 30);
	fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC |
			 IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
	nullfunc->frame_control = fc;
	memcpy(nullfunc->addr1, sdata->u.mgd.bssid, ETH_ALEN);
	memcpy(nullfunc->addr2, sdata->vif.addr, ETH_ALEN);
	memcpy(nullfunc->addr3, sdata->u.mgd.bssid, ETH_ALEN);
	memcpy(nullfunc->addr4, sdata->vif.addr, ETH_ALEN);

	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
	ieee80211_tx_skb(sdata, skb);
}

/* spectrum management related things */
static void ieee80211_chswitch_work(struct work_struct *work)
{
	struct ieee80211_sub_if_data *sdata =
		container_of(work, struct ieee80211_sub_if_data, u.mgd.chswitch_work);
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	int ret;

	if (!ieee80211_sdata_running(sdata))
		return;

	sdata_lock(sdata);
	mutex_lock(&local->mtx);
	mutex_lock(&local->chanctx_mtx);

	if (!ifmgd->associated)
		goto out;

	if (!sdata->vif.csa_active)
		goto out;

	/*
	 * using reservation isn't immediate as it may be deferred until later
	 * with multi-vif. once reservation is complete it will re-schedule the
	 * work with no reserved_chanctx so verify chandef to check if it
	 * completed successfully
	 */

	if (sdata->reserved_chanctx) {
		/*
		 * with multi-vif csa driver may call ieee80211_csa_finish()
		 * many times while waiting for other interfaces to use their
		 * reservations
		 */
		if (sdata->reserved_ready)
			goto out;

		ret = ieee80211_vif_use_reserved_context(sdata);
		if (ret) {
			sdata_info(sdata,
				   "failed to use reserved channel context, disconnecting (err=%d)\n",
				   ret);
			ieee80211_queue_work(&sdata->local->hw,
					     &ifmgd->csa_connection_drop_work);
			goto out;
		}

		goto out;
	}

	if (!cfg80211_chandef_identical(&sdata->vif.bss_conf.chandef,
					&sdata->csa_chandef)) {
		sdata_info(sdata,
			   "failed to finalize channel switch, disconnecting\n");
		ieee80211_queue_work(&sdata->local->hw,
				     &ifmgd->csa_connection_drop_work);
		goto out;
	}

	/* XXX: shouldn't really modify cfg80211-owned data! */
	ifmgd->associated->channel = sdata->csa_chandef.chan;

	ifmgd->csa_waiting_bcn = true;

	ieee80211_sta_reset_beacon_monitor(sdata);
	ieee80211_sta_reset_conn_monitor(sdata);

out:
	mutex_unlock(&local->chanctx_mtx);
	mutex_unlock(&local->mtx);
	sdata_unlock(sdata);
}

static void ieee80211_chswitch_post_beacon(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	int ret;

	sdata_assert_lock(sdata);

	WARN_ON(!sdata->vif.csa_active);

	if (sdata->csa_block_tx) {
		ieee80211_wake_vif_queues(local, sdata,
					  IEEE80211_QUEUE_STOP_REASON_CSA);
		sdata->csa_block_tx = false;
	}

	sdata->vif.csa_active = false;
	ifmgd->csa_waiting_bcn = false;

	ret = drv_post_channel_switch(sdata);
	if (ret) {
		sdata_info(sdata,
			   "driver post channel switch failed, disconnecting\n");
		ieee80211_queue_work(&local->hw,
				     &ifmgd->csa_connection_drop_work);
		return;
	}

	cfg80211_ch_switch_notify(sdata->dev, &sdata->reserved_chandef);
}

void ieee80211_chswitch_done(struct ieee80211_vif *vif, bool success)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;

	trace_api_chswitch_done(sdata, success);
	if (!success) {
		sdata_info(sdata,
			   "driver channel switch failed, disconnecting\n");
		ieee80211_queue_work(&sdata->local->hw,
				     &ifmgd->csa_connection_drop_work);
	} else {
		ieee80211_queue_work(&sdata->local->hw, &ifmgd->chswitch_work);
	}
}
EXPORT_SYMBOL(ieee80211_chswitch_done);

static void ieee80211_chswitch_timer(unsigned long data)
{
	struct ieee80211_sub_if_data *sdata =
		(struct ieee80211_sub_if_data *) data;

	ieee80211_queue_work(&sdata->local->hw, &sdata->u.mgd.chswitch_work);
}

static void
ieee80211_sta_process_chanswitch(struct ieee80211_sub_if_data *sdata,
				 u64 timestamp, u32 device_timestamp,
				 struct ieee802_11_elems *elems,
				 bool beacon)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	struct cfg80211_bss *cbss = ifmgd->associated;
	struct ieee80211_chanctx_conf *conf;
	struct ieee80211_chanctx *chanctx;
	enum ieee80211_band current_band;
	struct ieee80211_csa_ie csa_ie;
	struct ieee80211_channel_switch ch_switch;
	int res;

	sdata_assert_lock(sdata);

	if (!cbss)
		return;

	if (local->scanning)
		return;

	/* disregard subsequent announcements if we are already processing */
	if (sdata->vif.csa_active)
		return;

	current_band = cbss->channel->band;
	memset(&csa_ie, 0, sizeof(csa_ie));
	res = ieee80211_parse_ch_switch_ie(sdata, elems, current_band,
					   ifmgd->flags,
					   ifmgd->associated->bssid, &csa_ie);
	if (res	< 0)
		ieee80211_queue_work(&local->hw,
				     &ifmgd->csa_connection_drop_work);
	if (res)
		return;

	if (!cfg80211_chandef_usable(local->hw.wiphy, &csa_ie.chandef,
				     IEEE80211_CHAN_DISABLED)) {
		sdata_info(sdata,
			   "AP %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), disconnecting\n",
			   ifmgd->associated->bssid,
			   csa_ie.chandef.chan->center_freq,
			   csa_ie.chandef.width, csa_ie.chandef.center_freq1,
			   csa_ie.chandef.center_freq2);
		ieee80211_queue_work(&local->hw,
				     &ifmgd->csa_connection_drop_work);
		return;
	}

	if (cfg80211_chandef_identical(&csa_ie.chandef,
				       &sdata->vif.bss_conf.chandef)) {
		if (ifmgd->csa_ignored_same_chan)
			return;
		sdata_info(sdata,
			   "AP %pM tries to chanswitch to same channel, ignore\n",
			   ifmgd->associated->bssid);
		ifmgd->csa_ignored_same_chan = true;
		return;
	}

	/*
	 * Drop all TDLS peers - either we disconnect or move to a different
	 * channel from this point on. There's no telling what our peer will do.
	 * The TDLS WIDER_BW scenario is also problematic, as peers might now
	 * have an incompatible wider chandef.
	 */
	ieee80211_teardown_tdls_peers(sdata);

	mutex_lock(&local->mtx);
	mutex_lock(&local->chanctx_mtx);
	conf = rcu_dereference_protected(sdata->vif.chanctx_conf,
					 lockdep_is_held(&local->chanctx_mtx));
	if (!conf) {
		sdata_info(sdata,
			   "no channel context assigned to vif?, disconnecting\n");
		goto drop_connection;
	}

	chanctx = container_of(conf, struct ieee80211_chanctx, conf);

	if (local->use_chanctx &&
	    !ieee80211_hw_check(&local->hw, CHANCTX_STA_CSA)) {
		sdata_info(sdata,
			   "driver doesn't support chan-switch with channel contexts\n");
		goto drop_connection;
	}

	ch_switch.timestamp = timestamp;
	ch_switch.device_timestamp = device_timestamp;
	ch_switch.block_tx = csa_ie.mode;
	ch_switch.chandef = csa_ie.chandef;
	ch_switch.count = csa_ie.count;

	if (drv_pre_channel_switch(sdata, &ch_switch)) {
		sdata_info(sdata,
			   "preparing for channel switch failed, disconnecting\n");
		goto drop_connection;
	}

	res = ieee80211_vif_reserve_chanctx(sdata, &csa_ie.chandef,
					    chanctx->mode, false);
	if (res) {
		sdata_info(sdata,
			   "failed to reserve channel context for channel switch, disconnecting (err=%d)\n",
			   res);
		goto drop_connection;
	}
	mutex_unlock(&local->chanctx_mtx);

	sdata->vif.csa_active = true;
	sdata->csa_chandef = csa_ie.chandef;
	sdata->csa_block_tx = csa_ie.mode;
	ifmgd->csa_ignored_same_chan = false;

	if (sdata->csa_block_tx)
		ieee80211_stop_vif_queues(local, sdata,
					  IEEE80211_QUEUE_STOP_REASON_CSA);
	mutex_unlock(&local->mtx);

	cfg80211_ch_switch_started_notify(sdata->dev, &csa_ie.chandef,
					  csa_ie.count);

	if (local->ops->channel_switch) {
		/* use driver's channel switch callback */
		drv_channel_switch(local, sdata, &ch_switch);
		return;
	}

	/* channel switch handled in software */
	if (csa_ie.count <= 1)
		ieee80211_queue_work(&local->hw, &ifmgd->chswitch_work);
	else
		mod_timer(&ifmgd->chswitch_timer,
			  TU_TO_EXP_TIME((csa_ie.count - 1) *
					 cbss->beacon_interval));
	return;
 drop_connection:
	ieee80211_queue_work(&local->hw, &ifmgd->csa_connection_drop_work);
	mutex_unlock(&local->chanctx_mtx);
	mutex_unlock(&local->mtx);
}

static bool
ieee80211_find_80211h_pwr_constr(struct ieee80211_sub_if_data *sdata,
				 struct ieee80211_channel *channel,
				 const u8 *country_ie, u8 country_ie_len,
				 const u8 *pwr_constr_elem,
				 int *chan_pwr, int *pwr_reduction)
{
	struct ieee80211_country_ie_triplet *triplet;
	int chan = ieee80211_frequency_to_channel(channel->center_freq);
	int i, chan_increment;
	bool have_chan_pwr = false;

	/* Invalid IE */
	if (country_ie_len % 2 || country_ie_len < IEEE80211_COUNTRY_IE_MIN_LEN)
		return false;

	triplet = (void *)(country_ie + 3);
	country_ie_len -= 3;

	switch (channel->band) {
	default:
		WARN_ON_ONCE(1);
		/* fall through */
	case IEEE80211_BAND_2GHZ:
	case IEEE80211_BAND_60GHZ:
		chan_increment = 1;
		break;
	case IEEE80211_BAND_5GHZ:
		chan_increment = 4;
		break;
	}

	/* find channel */
	while (country_ie_len >= 3) {
		u8 first_channel = triplet->chans.first_channel;

		if (first_channel >= IEEE80211_COUNTRY_EXTENSION_ID)
			goto next;

		for (i = 0; i < triplet->chans.num_channels; i++) {
			if (first_channel + i * chan_increment == chan) {
				have_chan_pwr = true;
				*chan_pwr = triplet->chans.max_power;
				break;
			}
		}
		if (have_chan_pwr)
			break;

 next:
		triplet++;
		country_ie_len -= 3;
	}

	if (have_chan_pwr && pwr_constr_elem)
		*pwr_reduction = *pwr_constr_elem;
	else
		*pwr_reduction = 0;

	return have_chan_pwr;
}

static void ieee80211_find_cisco_dtpc(struct ieee80211_sub_if_data *sdata,
				      struct ieee80211_channel *channel,
				      const u8 *cisco_dtpc_ie,
				      int *pwr_level)
{
	/* From practical testing, the first data byte of the DTPC element
	 * seems to contain the requested dBm level, and the CLI on Cisco
	 * APs clearly state the range is -127 to 127 dBm, which indicates
	 * a signed byte, although it seemingly never actually goes negative.
	 * The other byte seems to always be zero.
	 */
	*pwr_level = (__s8)cisco_dtpc_ie[4];
}

static u32 ieee80211_handle_pwr_constr(struct ieee80211_sub_if_data *sdata,
				       struct ieee80211_channel *channel,
				       struct ieee80211_mgmt *mgmt,
				       const u8 *country_ie, u8 country_ie_len,
				       const u8 *pwr_constr_ie,
				       const u8 *cisco_dtpc_ie)
{
	bool has_80211h_pwr = false, has_cisco_pwr = false;
	int chan_pwr = 0, pwr_reduction_80211h = 0;
	int pwr_level_cisco, pwr_level_80211h;
	int new_ap_level;
	__le16 capab = mgmt->u.probe_resp.capab_info;

	if (country_ie &&
	    (capab & cpu_to_le16(WLAN_CAPABILITY_SPECTRUM_MGMT) ||
	     capab & cpu_to_le16(WLAN_CAPABILITY_RADIO_MEASURE))) {
		has_80211h_pwr = ieee80211_find_80211h_pwr_constr(
			sdata, channel, country_ie, country_ie_len,
			pwr_constr_ie, &chan_pwr, &pwr_reduction_80211h);
		pwr_level_80211h =
			max_t(int, 0, chan_pwr - pwr_reduction_80211h);
	}

	if (cisco_dtpc_ie) {
		ieee80211_find_cisco_dtpc(
			sdata, channel, cisco_dtpc_ie, &pwr_level_cisco);
		has_cisco_pwr = true;
	}

	if (!has_80211h_pwr && !has_cisco_pwr)
		return 0;

	/* If we have both 802.11h and Cisco DTPC, apply both limits
	 * by picking the smallest of the two power levels advertised.
	 */
	if (has_80211h_pwr &&
	    (!has_cisco_pwr || pwr_level_80211h <= pwr_level_cisco)) {
		new_ap_level = pwr_level_80211h;

		if (sdata->ap_power_level == new_ap_level)
			return 0;

		sdata_dbg(sdata,
			  "Limiting TX power to %d (%d - %d) dBm as advertised by %pM\n",
			  pwr_level_80211h, chan_pwr, pwr_reduction_80211h,
			  sdata->u.mgd.bssid);
	} else {  /* has_cisco_pwr is always true here. */
		new_ap_level = pwr_level_cisco;

		if (sdata->ap_power_level == new_ap_level)
			return 0;

		sdata_dbg(sdata,
			  "Limiting TX power to %d dBm as advertised by %pM\n",
			  pwr_level_cisco, sdata->u.mgd.bssid);
	}

	sdata->ap_power_level = new_ap_level;
	if (__ieee80211_recalc_txpower(sdata))
		return BSS_CHANGED_TXPOWER;
	return 0;
}

/* powersave */
static void ieee80211_enable_ps(struct ieee80211_local *local,
				struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_conf *conf = &local->hw.conf;

	/*
	 * If we are scanning right now then the parameters will
	 * take effect when scan finishes.
	 */
	if (local->scanning)
		return;

	if (conf->dynamic_ps_timeout > 0 &&
	    !ieee80211_hw_check(&local->hw, SUPPORTS_DYNAMIC_PS)) {
		mod_timer(&local->dynamic_ps_timer, jiffies +
			  msecs_to_jiffies(conf->dynamic_ps_timeout));
	} else {
		if (ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK))
			ieee80211_send_nullfunc(local, sdata, true);

		if (ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK) &&
		    ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS))
			return;

		conf->flags |= IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
	}
}

static void ieee80211_change_ps(struct ieee80211_local *local)
{
	struct ieee80211_conf *conf = &local->hw.conf;

	if (local->ps_sdata) {
		ieee80211_enable_ps(local, local->ps_sdata);
	} else if (conf->flags & IEEE80211_CONF_PS) {
		conf->flags &= ~IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
		del_timer_sync(&local->dynamic_ps_timer);
		cancel_work_sync(&local->dynamic_ps_enable_work);
	}
}

static bool ieee80211_powersave_allowed(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_if_managed *mgd = &sdata->u.mgd;
	struct sta_info *sta = NULL;
	bool authorized = false;

	if (!mgd->powersave)
		return false;

	if (mgd->broken_ap)
		return false;

	if (!mgd->associated)
		return false;

	if (mgd->flags & IEEE80211_STA_CONNECTION_POLL)
		return false;

	if (!mgd->have_beacon)
		return false;

	rcu_read_lock();
	sta = sta_info_get(sdata, mgd->bssid);
	if (sta)
		authorized = test_sta_flag(sta, WLAN_STA_AUTHORIZED);
	rcu_read_unlock();

	return authorized;
}

/* need to hold RTNL or interface lock */
void ieee80211_recalc_ps(struct ieee80211_local *local)
{
	struct ieee80211_sub_if_data *sdata, *found = NULL;
	int count = 0;
	int timeout;

	if (!ieee80211_hw_check(&local->hw, SUPPORTS_PS)) {
		local->ps_sdata = NULL;
		return;
	}

	list_for_each_entry(sdata, &local->interfaces, list) {
		if (!ieee80211_sdata_running(sdata))
			continue;
		if (sdata->vif.type == NL80211_IFTYPE_AP) {
			/* If an AP vif is found, then disable PS
			 * by setting the count to zero thereby setting
			 * ps_sdata to NULL.
			 */
			count = 0;
			break;
		}
		if (sdata->vif.type != NL80211_IFTYPE_STATION)
			continue;
		found = sdata;
		count++;
	}

	if (count == 1 && ieee80211_powersave_allowed(found)) {
		u8 dtimper = found->u.mgd.dtim_period;
		s32 beaconint_us;

		beaconint_us = ieee80211_tu_to_usec(
					found->vif.bss_conf.beacon_int);

		timeout = local->dynamic_ps_forced_timeout;
		if (timeout < 0)
			timeout = 100;
		local->hw.conf.dynamic_ps_timeout = timeout;

		/* If the TIM IE is invalid, pretend the value is 1 */
		if (!dtimper)
			dtimper = 1;

		local->hw.conf.ps_dtim_period = dtimper;
		local->ps_sdata = found;
	} else {
		local->ps_sdata = NULL;
	}

	ieee80211_change_ps(local);
}

void ieee80211_recalc_ps_vif(struct ieee80211_sub_if_data *sdata)
{
	bool ps_allowed = ieee80211_powersave_allowed(sdata);

	if (sdata->vif.bss_conf.ps != ps_allowed) {
		sdata->vif.bss_conf.ps = ps_allowed;
		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_PS);
	}
}

void ieee80211_dynamic_ps_disable_work(struct work_struct *work)
{
	struct ieee80211_local *local =
		container_of(work, struct ieee80211_local,
			     dynamic_ps_disable_work);

	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
		local->hw.conf.flags &= ~IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
	}

	ieee80211_wake_queues_by_reason(&local->hw,
					IEEE80211_MAX_QUEUE_MAP,
					IEEE80211_QUEUE_STOP_REASON_PS,
					false);
}

void ieee80211_dynamic_ps_enable_work(struct work_struct *work)
{
	struct ieee80211_local *local =
		container_of(work, struct ieee80211_local,
			     dynamic_ps_enable_work);
	struct ieee80211_sub_if_data *sdata = local->ps_sdata;
	struct ieee80211_if_managed *ifmgd;
	unsigned long flags;
	int q;

	/* can only happen when PS was just disabled anyway */
	if (!sdata)
		return;

	ifmgd = &sdata->u.mgd;

	if (local->hw.conf.flags & IEEE80211_CONF_PS)
		return;

	if (local->hw.conf.dynamic_ps_timeout > 0) {
		/* don't enter PS if TX frames are pending */
		if (drv_tx_frames_pending(local)) {
			mod_timer(&local->dynamic_ps_timer, jiffies +
				  msecs_to_jiffies(
				  local->hw.conf.dynamic_ps_timeout));
			return;
		}

		/*
		 * transmission can be stopped by others which leads to
		 * dynamic_ps_timer expiry. Postpone the ps timer if it
		 * is not the actual idle state.
		 */
		spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
		for (q = 0; q < local->hw.queues; q++) {
			if (local->queue_stop_reasons[q]) {
				spin_unlock_irqrestore(&local->queue_stop_reason_lock,
						       flags);
				mod_timer(&local->dynamic_ps_timer, jiffies +
					  msecs_to_jiffies(
					  local->hw.conf.dynamic_ps_timeout));
				return;
			}
		}
		spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
	}

	if (ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK) &&
	    !(ifmgd->flags & IEEE80211_STA_NULLFUNC_ACKED)) {
		if (drv_tx_frames_pending(local)) {
			mod_timer(&local->dynamic_ps_timer, jiffies +
				  msecs_to_jiffies(
				  local->hw.conf.dynamic_ps_timeout));
		} else {
			ieee80211_send_nullfunc(local, sdata, true);
			/* Flush to get the tx status of nullfunc frame */
			ieee80211_flush_queues(local, sdata, false);
		}
	}

	if (!(ieee80211_hw_check(&local->hw, REPORTS_TX_ACK_STATUS) &&
	      ieee80211_hw_check(&local->hw, PS_NULLFUNC_STACK)) ||
	    (ifmgd->flags & IEEE80211_STA_NULLFUNC_ACKED)) {
		ifmgd->flags &= ~IEEE80211_STA_NULLFUNC_ACKED;
		local->hw.conf.flags |= IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
	}
}

void ieee80211_dynamic_ps_timer(unsigned long data)
{
	struct ieee80211_local *local = (void *) data;

	ieee80211_queue_work(&local->hw, &local->dynamic_ps_enable_work);
}

void ieee80211_dfs_cac_timer_work(struct work_struct *work)
{
	struct delayed_work *delayed_work = to_delayed_work(work);
	struct ieee80211_sub_if_data *sdata =
		container_of(delayed_work, struct ieee80211_sub_if_data,
			     dfs_cac_timer_work);
	struct cfg80211_chan_def chandef = sdata->vif.bss_conf.chandef;

	mutex_lock(&sdata->local->mtx);
	if (sdata->wdev.cac_started) {
		ieee80211_vif_release_channel(sdata);
		cfg80211_cac_event(sdata->dev, &chandef,
				   NL80211_RADAR_CAC_FINISHED,
				   GFP_KERNEL);
	}
	mutex_unlock(&sdata->local->mtx);
}

static bool
__ieee80211_sta_handle_tspec_ac_params(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	bool ret = false;
	int ac;

	if (local->hw.queues < IEEE80211_NUM_ACS)
		return false;

	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
		struct ieee80211_sta_tx_tspec *tx_tspec = &ifmgd->tx_tspec[ac];
		int non_acm_ac;
		unsigned long now = jiffies;

		if (tx_tspec->action == TX_TSPEC_ACTION_NONE &&
		    tx_tspec->admitted_time &&
		    time_after(now, tx_tspec->time_slice_start + HZ)) {
			tx_tspec->consumed_tx_time = 0;
			tx_tspec->time_slice_start = now;

			if (tx_tspec->downgraded)
				tx_tspec->action =
					TX_TSPEC_ACTION_STOP_DOWNGRADE;
		}

		switch (tx_tspec->action) {
		case TX_TSPEC_ACTION_STOP_DOWNGRADE:
			/* take the original parameters */
			if (drv_conf_tx(local, sdata, ac, &sdata->tx_conf[ac]))
				sdata_err(sdata,
					  "failed to set TX queue parameters for queue %d\n",
					  ac);
			tx_tspec->action = TX_TSPEC_ACTION_NONE;
			tx_tspec->downgraded = false;
			ret = true;
			break;
		case TX_TSPEC_ACTION_DOWNGRADE:
			if (time_after(now, tx_tspec->time_slice_start + HZ)) {
				tx_tspec->action = TX_TSPEC_ACTION_NONE;
				ret = true;
				break;
			}
			/* downgrade next lower non-ACM AC */
			for (non_acm_ac = ac + 1;
			     non_acm_ac < IEEE80211_NUM_ACS;
			     non_acm_ac++)
				if (!(sdata->wmm_acm & BIT(7 - 2 * non_acm_ac)))
					break;
			/* The loop will result in using BK even if it requires
			 * admission control, such configuration makes no sense
			 * and we have to transmit somehow - the AC selection
			 * does the same thing.
			 */
			if (drv_conf_tx(local, sdata, ac,
					&sdata->tx_conf[non_acm_ac]))
				sdata_err(sdata,
					  "failed to set TX queue parameters for queue %d\n",
					  ac);
			tx_tspec->action = TX_TSPEC_ACTION_NONE;
			ret = true;
			schedule_delayed_work(&ifmgd->tx_tspec_wk,
				tx_tspec->time_slice_start + HZ - now + 1);
			break;
		case TX_TSPEC_ACTION_NONE:
			/* nothing now */
			break;
		}
	}

	return ret;
}

void ieee80211_sta_handle_tspec_ac_params(struct ieee80211_sub_if_data *sdata)
{
	if (__ieee80211_sta_handle_tspec_ac_params(sdata))
		ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_QOS);
}

static void ieee80211_sta_handle_tspec_ac_params_wk(struct work_struct *work)
{
	struct ieee80211_sub_if_data *sdata;

	sdata = container_of(work, struct ieee80211_sub_if_data,
			     u.mgd.tx_tspec_wk.work);
	ieee80211_sta_handle_tspec_ac_params(sdata);
}

/* MLME */
static bool ieee80211_sta_wmm_params(struct ieee80211_local *local,
				     struct ieee80211_sub_if_data *sdata,
				     const u8 *wmm_param, size_t wmm_param_len)
{
	struct ieee80211_tx_queue_params params[IEEE80211_NUM_ACS];
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	size_t left;
	int count, ac;
	const u8 *pos;
	u8 uapsd_queues = 0;

	if (!local->ops->conf_tx)
		return false;

	if (local->hw.queues < IEEE80211_NUM_ACS)
		return false;

	if (!wmm_param)
		return false;

	if (wmm_param_len < 8 || wmm_param[5] /* version */ != 1)
		return false;

	if (ifmgd->flags & IEEE80211_STA_UAPSD_ENABLED)
		uapsd_queues = ifmgd->uapsd_queues;

	count = wmm_param[6] & 0x0f;
	if (count == ifmgd->wmm_last_param_set)
		return false;
	ifmgd->wmm_last_param_set = count;

	pos = wmm_param + 8;
	left = wmm_param_len - 8;

	memset(&params, 0, sizeof(params));

	sdata->wmm_acm = 0;
	for (; left >= 4; left -= 4, pos += 4) {
		int aci = (pos[0] >> 5) & 0x03;
		int acm = (pos[0] >> 4) & 0x01;
		bool uapsd = false;

		switch (aci) {
		case 1: /* AC_BK */
			ac = IEEE80211_AC_BK;
			if (acm)
				sdata->wmm_acm |= BIT(1) | BIT(2); /* BK/- */
			if (uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_BK)
				uapsd = true;
			break;
		case 2: /* AC_VI */
			ac = IEEE80211_AC_VI;
			if (acm)
				sdata->wmm_acm |= BIT(4) | BIT(5); /* CL/VI */
			if (uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VI)
				uapsd = true;
			break;
		case 3: /* AC_VO */
			ac = IEEE80211_AC_VO;
			if (acm)
				sdata->wmm_acm |= BIT(6) | BIT(7); /* VO/NC */
			if (uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_VO)
				uapsd = true;
			break;
		case 0: /* AC_BE */
		default:
			ac = IEEE80211_AC_BE;
			if (acm)
				sdata->wmm_acm |= BIT(0) | BIT(3); /* BE/EE */
			if (uapsd_queues & IEEE80211_WMM_IE_STA_QOSINFO_AC_BE)
				uapsd = true;
			break;
		}

		params[ac].aifs = pos[0] & 0x0f;

		if (params[ac].aifs < 2) {
			sdata_info(sdata,
				   "AP has invalid WMM params (AIFSN=%d for ACI %d), will use 2\n",
				   params[ac].aifs, aci);
			params[ac].aifs = 2;
		}
		params[ac].cw_max = ecw2cw((pos[1] & 0xf0) >> 4);
		params[ac].cw_min = ecw2cw(pos[1] & 0x0f);
		params[ac].txop = get_unaligned_le16(pos + 2);
		params[ac].acm = acm;
		params[ac].uapsd = uapsd;

		if (params[ac].cw_min > params[ac].cw_max) {
			sdata_info(sdata,
				   "AP has invalid WMM params (CWmin/max=%d/%d for ACI %d), using defaults\n",
				   params[ac].cw_min, params[ac].cw_max, aci);
			return false;
		}
	}

	for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
		mlme_dbg(sdata,
			 "WMM AC=%d acm=%d aifs=%d cWmin=%d cWmax=%d txop=%d uapsd=%d, downgraded=%d\n",
			 ac, params[ac].acm,
			 params[ac].aifs, params[ac].cw_min, params[ac].cw_max,
			 params[ac].txop, params[ac].uapsd,
			 ifmgd->tx_tspec[ac].downgraded);
		sdata->tx_conf[ac] = params[ac];
		if (!ifmgd->tx_tspec[ac].downgraded &&
		    drv_conf_tx(local, sdata, ac, &params[ac]))
			sdata_err(sdata,
				  "failed to set TX queue parameters for AC %d\n",
				  ac);
	}

	/* enable WMM or activate new settings */
	sdata->vif.bss_conf.qos = true;
	return true;
}

static void __ieee80211_stop_poll(struct ieee80211_sub_if_data *sdata)
{
	lockdep_assert_held(&sdata->local->mtx);

	sdata->u.mgd.flags &= ~IEEE80211_STA_CONNECTION_POLL;
	ieee80211_run_deferred_scan(sdata->local);
}

static void ieee80211_stop_poll(struct ieee80211_sub_if_data *sdata)
{
	mutex_lock(&sdata->local->mtx);
	__ieee80211_stop_poll(sdata);
	mutex_unlock(&sdata->local->mtx);
}

static u32 ieee80211_handle_bss_capability(struct ieee80211_sub_if_data *sdata,
					   u16 capab, bool erp_valid, u8 erp)
{
	struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;
	u32 changed = 0;
	bool use_protection;
	bool use_short_preamble;
	bool use_short_slot;

	if (erp_valid) {
		use_protection = (erp & WLAN_ERP_USE_PROTECTION) != 0;
		use_short_preamble = (erp & WLAN_ERP_BARKER_PREAMBLE) == 0;
	} else {
		use_protection = false;
		use_short_preamble = !!(capab & WLAN_CAPABILITY_SHORT_PREAMBLE);
	}

	use_short_slot = !!(capab & WLAN_CAPABILITY_SHORT_SLOT_TIME);
	if (ieee80211_get_sdata_band(sdata) == IEEE80211_BAND_5GHZ)
		use_short_slot = true;

	if (use_protection != bss_conf->use_cts_prot) {
		bss_conf->use_cts_prot = use_protection;
		changed |= BSS_CHANGED_ERP_CTS_PROT;
	}

	if (use_short_preamble != bss_conf->use_short_preamble) {
		bss_conf->use_short_preamble = use_short_preamble;
		changed |= BSS_CHANGED_ERP_PREAMBLE;
	}

	if (use_short_slot != bss_conf->use_short_slot) {
		bss_conf->use_short_slot = use_short_slot;
		changed |= BSS_CHANGED_ERP_SLOT;
	}

	return changed;
}

static void ieee80211_set_associated(struct ieee80211_sub_if_data *sdata,
				     struct cfg80211_bss *cbss,
				     u32 bss_info_changed)
{
	struct ieee80211_bss *bss = (void *)cbss->priv;
	struct ieee80211_local *local = sdata->local;
	struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;

	bss_info_changed |= BSS_CHANGED_ASSOC;
	bss_info_changed |= ieee80211_handle_bss_capability(sdata,
		bss_conf->assoc_capability, bss->has_erp_value, bss->erp_value);

	sdata->u.mgd.beacon_timeout = usecs_to_jiffies(ieee80211_tu_to_usec(
		beacon_loss_count * bss_conf->beacon_int));

	sdata->u.mgd.associated = cbss;
	memcpy(sdata->u.mgd.bssid, cbss->bssid, ETH_ALEN);

	sdata->u.mgd.flags |= IEEE80211_STA_RESET_SIGNAL_AVE;

	if (sdata->vif.p2p ||
	    sdata->vif.driver_flags & IEEE80211_VIF_GET_NOA_UPDATE) {
		const struct cfg80211_bss_ies *ies;

		rcu_read_lock();
		ies = rcu_dereference(cbss->ies);
		if (ies) {
			int ret;

			ret = cfg80211_get_p2p_attr(
					ies->data, ies->len,
					IEEE80211_P2P_ATTR_ABSENCE_NOTICE,
					(u8 *) &bss_conf->p2p_noa_attr,
					sizeof(bss_conf->p2p_noa_attr));
			if (ret >= 2) {
				sdata->u.mgd.p2p_noa_index =
					bss_conf->p2p_noa_attr.index;
				bss_info_changed |= BSS_CHANGED_P2P_PS;
			}
		}
		rcu_read_unlock();
	}

	/* just to be sure */
	ieee80211_stop_poll(sdata);

	ieee80211_led_assoc(local, 1);

	if (sdata->u.mgd.have_beacon) {
		/*
		 * If the AP is buggy we may get here with no DTIM period
		 * known, so assume it's 1 which is the only safe assumption
		 * in that case, although if the TIM IE is broken powersave
		 * probably just won't work at all.
		 */
		bss_conf->dtim_period = sdata->u.mgd.dtim_period ?: 1;
		bss_conf->beacon_rate = bss->beacon_rate;
		bss_info_changed |= BSS_CHANGED_BEACON_INFO;
	} else {
		bss_conf->beacon_rate = NULL;
		bss_conf->dtim_period = 0;
	}

	bss_conf->assoc = 1;

	/* Tell the driver to monitor connection quality (if supported) */
	if (sdata->vif.driver_flags & IEEE80211_VIF_SUPPORTS_CQM_RSSI &&
	    bss_conf->cqm_rssi_thold)
		bss_info_changed |= BSS_CHANGED_CQM;

	/* Enable ARP filtering */
	if (bss_conf->arp_addr_cnt)
		bss_info_changed |= BSS_CHANGED_ARP_FILTER;

	ieee80211_bss_info_change_notify(sdata, bss_info_changed);

	mutex_lock(&local->iflist_mtx);
	ieee80211_recalc_ps(local);
	mutex_unlock(&local->iflist_mtx);

	ieee80211_recalc_smps(sdata);
	ieee80211_recalc_ps_vif(sdata);

	netif_carrier_on(sdata->dev);
}

static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
				   u16 stype, u16 reason, bool tx,
				   u8 *frame_buf)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	struct ieee80211_local *local = sdata->local;
	u32 changed = 0;

	sdata_assert_lock(sdata);

	if (WARN_ON_ONCE(tx && !frame_buf))
		return;

	if (WARN_ON(!ifmgd->associated))
		return;

	ieee80211_stop_poll(sdata);

	ifmgd->associated = NULL;
	netif_carrier_off(sdata->dev);

	/*
	 * if we want to get out of ps before disassoc (why?) we have
	 * to do it before sending disassoc, as otherwise the null-packet
	 * won't be valid.
	 */
	if (local->hw.conf.flags & IEEE80211_CONF_PS) {
		local->hw.conf.flags &= ~IEEE80211_CONF_PS;
		ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_PS);
	}
	local->ps_sdata = NULL;

	/* disable per-vif ps */
	ieee80211_recalc_ps_vif(sdata);

	/* make sure ongoing transmission finishes */
	synchronize_net();

	/*
	 * drop any frame before deauth/disassoc, this can be data or
	 * management frame. Since we are disconnecting, we should not
	 * insist sending these frames which can take time and delay
	 * the disconnection and possible the roaming.
	 */
	if (tx)
		ieee80211_flush_queues(local, sdata, true);

	/* deauthenticate/disassociate now */
	if (tx || frame_buf)
		ieee80211_send_deauth_disassoc(sdata, ifmgd->bssid, stype,
					       reason, tx, frame_buf);

	/* flush out frame - make sure the deauth was actually sent */
	if (tx)
		ieee80211_flush_queues(local, sdata, false);

	/* clear bssid only after building the needed mgmt frames */
	eth_zero_addr(ifmgd->bssid);

	/* remove AP and TDLS peers */
	sta_info_flush(sdata);

	/* finally reset all BSS / config parameters */
	changed |= ieee80211_reset_erp_info(sdata);

	ieee80211_led_assoc(local, 0);
	changed |= BSS_CHANGED_ASSOC;
	sdata->vif.bss_conf.assoc = false;

	ifmgd->p2p_noa_index = -1;
	memset(&sdata->vif.bss_conf.p2p_noa_attr, 0,
	       sizeof(sdata->vif.bss_conf.p2p_noa_attr));

	/* on the next assoc, re-program HT/VHT parameters */
	memset(&ifmgd->ht_capa, 0, sizeof(ifmgd->ht_capa));
	memset(&ifmgd->ht_capa_mask, 0, sizeof(ifmgd->ht_capa_mask));
	memset(&ifmgd->vht_capa, 0, sizeof(ifmgd->vht_capa));
	memset(&ifmgd->vht_capa_mask, 0, sizeof(ifmgd->vht_capa_mask));

	/* reset MU-MIMO ownership and group data */
	memset(sdata->vif.bss_conf.mu_group.membership, 0,
	       sizeof(sdata->vif.bss_conf.mu_group.membership));
	memset(sdata->vif.bss_conf.mu_group.position, 0,
	       sizeof(sdata->vif.bss_conf.mu_group.position));
	changed |= BSS_CHANGED_MU_GROUPS;
	sdata->vif.mu_mimo_owner = false;

	sdata->ap_power_level = IEEE80211_UNSET_POWER_LEVEL;

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

	/* Disable ARP filtering */
	if (sdata->vif.bss_conf.arp_addr_cnt)
		changed |= BSS_CHANGED_ARP_FILTER;

	sdata->vif.bss_conf.qos = false;
	changed |= BSS_CHANGED_QOS;

	/* The BSSID (not really interesting) and HT changed */
	changed |= BSS_CHANGED_BSSID | BSS_CHANGED_HT;
	ieee80211_bss_info_change_notify(sdata, changed);

	/* disassociated - set to defaults now */
	ieee80211_set_wmm_default(sdata, false, false);

	del_timer_sync(&sdata->u.mgd.conn_mon_timer);
	del_timer_sync(&sdata->u.mgd.bcn_mon_timer);
	del_timer_sync(&sdata->u.mgd.timer);
	del_timer_sync(&sdata->u.mgd.chswitch_timer);

	sdata->vif.bss_conf.dtim_period = 0;
	sdata->vif.bss_conf.beacon_rate = NULL;

	ifmgd->have_beacon = false;

	ifmgd->flags = 0;
	mutex_lock(&local->mtx);
	ieee80211_vif_release_channel(sdata);

	sdata->vif.csa_active = false;
	ifmgd->csa_waiting_bcn = false;
	ifmgd->csa_ignored_same_chan = false;
	if (sdata->csa_block_tx) {
		ieee80211_wake_vif_queues(local, sdata,
					  IEEE80211_QUEUE_STOP_REASON_CSA);
		sdata->csa_block_tx = false;
	}
	mutex_unlock(&local->mtx);

	/* existing TX TSPEC sessions no longer exist */
	memset(ifmgd->tx_tspec, 0, sizeof(ifmgd->tx_tspec));
	cancel_delayed_work_sync(&ifmgd->tx_tspec_wk);

	sdata->encrypt_headroom = IEEE80211_ENCRYPT_HEADROOM;
}

void ieee80211_sta_rx_notify(struct ieee80211_sub_if_data *sdata,
			     struct ieee80211_hdr *hdr)
{
	/*
	 * We can postpone the mgd.timer whenever receiving unicast frames
	 * from AP because we know that the connection is working both ways
	 * at that time. But multicast frames (and hence also beacons) must
	 * be ignored here, because we need to trigger the timer during
	 * data idle periods for sending the periodic probe request to the
	 * AP we're connected to.
	 */
	if (is_multicast_ether_addr(hdr->addr1))
		return;

	ieee80211_sta_reset_conn_monitor(sdata);
}

static void ieee80211_reset_ap_probe(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	struct ieee80211_local *local = sdata->local;

	mutex_lock(&local->mtx);
	if (!(ifmgd->flags & IEEE80211_STA_CONNECTION_POLL))
		goto out;

	__ieee80211_stop_poll(sdata);

	mutex_lock(&local->iflist_mtx);
	ieee80211_recalc_ps(local);
	mutex_unlock(&local->iflist_mtx);

	if (ieee80211_hw_check(&sdata->local->hw, CONNECTION_MONITOR))
		goto out;

	/*
	 * We've received a probe response, but are not sure whether
	 * we have or will be receiving any beacons or data, so let's
	 * schedule the timers again, just in case.
	 */
	ieee80211_sta_reset_beacon_monitor(sdata);

	mod_timer(&ifmgd->conn_mon_timer,
		  round_jiffies_up(jiffies +
				   IEEE80211_CONNECTION_IDLE_TIME));
out:
	mutex_unlock(&local->mtx);
}

static void ieee80211_sta_tx_wmm_ac_notify(struct ieee80211_sub_if_data *sdata,
					   struct ieee80211_hdr *hdr,
					   u16 tx_time)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	u16 tid = *ieee80211_get_qos_ctl(hdr) & IEEE80211_QOS_CTL_TID_MASK;
	int ac = ieee80211_ac_from_tid(tid);
	struct ieee80211_sta_tx_tspec *tx_tspec = &ifmgd->tx_tspec[ac];
	unsigned long now = jiffies;

	if (likely(!tx_tspec->admitted_time))
		return;

	if (time_after(now, tx_tspec->time_slice_start + HZ)) {
		tx_tspec->consumed_tx_time = 0;
		tx_tspec->time_slice_start = now;

		if (tx_tspec->downgraded) {
			tx_tspec->action = TX_TSPEC_ACTION_STOP_DOWNGRADE;
			schedule_delayed_work(&ifmgd->tx_tspec_wk, 0);
		}
	}

	if (tx_tspec->downgraded)
		return;

	tx_tspec->consumed_tx_time += tx_time;

	if (tx_tspec->consumed_tx_time >= tx_tspec->admitted_time) {
		tx_tspec->downgraded = true;
		tx_tspec->action = TX_TSPEC_ACTION_DOWNGRADE;
		schedule_delayed_work(&ifmgd->tx_tspec_wk, 0);
	}
}

void ieee80211_sta_tx_notify(struct ieee80211_sub_if_data *sdata,
			     struct ieee80211_hdr *hdr, bool ack, u16 tx_time)
{
	ieee80211_sta_tx_wmm_ac_notify(sdata, hdr, tx_time);

	if (!ieee80211_is_data(hdr->frame_control))
	    return;

	if (ieee80211_is_nullfunc(hdr->frame_control) &&
	    sdata->u.mgd.probe_send_count > 0) {
		if (ack)
			ieee80211_sta_reset_conn_monitor(sdata);
		else
			sdata->u.mgd.nullfunc_failed = true;
		ieee80211_queue_work(&sdata->local->hw, &sdata->work);
		return;
	}

	if (ack)
		ieee80211_sta_reset_conn_monitor(sdata);
}

static void ieee80211_mgd_probe_ap_send(struct ieee80211_sub_if_data *sdata)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	const u8 *ssid;
	u8 *dst = ifmgd->associated->bssid;
	u8 unicast_limit = max(1, max_probe_tries - 3);

	/*
	 * Try sending broadcast probe requests for the last three
	 * probe requests after the first ones failed since some
	 * buggy APs only support broadcast probe requests.
	 */
	if (ifmgd->probe_send_count >= unicast_limit)
		dst = NULL;

	/*
	 * When the hardware reports an accurate Tx ACK status, it's
	 * better to send a nullfunc frame instead of a probe request,
	 * as it will kick us off the AP quickly if we aren't associated
	 * anymore. The timeout will be reset if the frame is ACKed by
	 * the AP.
	 */
	ifmgd->probe_send_count++;

	if (ieee80211_hw_check(&sdata->local->hw, REPORTS_TX_ACK_STATUS)) {
		ifmgd->nullfunc_failed = false;
		ieee80211_send_nullfunc(sdata->local, sdata, false);
	} else {
		int ssid_len;

		rcu_read_lock();
		ssid = ieee80211_bss_get_ie(ifmgd->associated, WLAN_EID_SSID);
		if (WARN_ON_ONCE(ssid == NULL))
			ssid_len = 0;
		else
			ssid_len = ssid[1];

		ieee80211_send_probe_req(sdata, sdata->vif.addr, dst,
					 ssid + 2, ssid_len, NULL,
					 0, (u32) -1, true, 0,
					 ifmgd->associated->channel, false);
		rcu_read_unlock();
	}

	ifmgd->probe_timeout = jiffies + msecs_to_jiffies(probe_wait_ms);
	run_again(sdata, ifmgd->probe_timeout);
}

static void ieee80211_mgd_probe_ap(struct ieee80211_sub_if_data *sdata,
				   bool beacon)
{
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	bool already = false;

	if (!ieee80211_sdata_running(sdata))
		return;

	sdata_lock(sdata);

	if (!ifmgd->associated)
		goto out;

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

	if (sdata->local->tmp_channel || sdata->local->scanning) {
		mutex_unlock(&sdata->local->mtx);
		goto out;
	}

	if (beacon) {
		mlme_dbg_ratelimited(sdata,
				     "detected beacon loss from AP (missed %d beacons) - probing\n",
				     beacon_loss_count);

		ieee80211_cqm_beacon_loss_notify(&sdata->vif, GFP_KERNEL);
	}

	/*
	 * The driver/our work has already reported this event or the
	 * connection monitoring has kicked in and we have already sent
	 * a probe request. Or maybe the AP died and the driver keeps
	 * reporting until we disassociate...
	 *
	 * In either case we have to ignore the current call to this
	 * function (except for setting the correct probe reason bit)
	 * because otherwise we would reset the timer every time and
	 * never check whether we received a probe response!
	 */
	if (ifmgd->flags & IEEE80211_STA_CONNECTION_POLL)
		already = true;

	ifmgd->flags |= IEEE80211_STA_CONNECTION_POLL;

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

	if (already)
		goto out;

	mutex_lock(&sdata->local->iflist_mtx);
	ieee80211_recalc_ps(sdata->local);
	mutex_unlock(&sdata->local->iflist_mtx);

	ifmgd->probe_send_count = 0;
	ieee80211_mgd_probe_ap_send(sdata);
 out:
	sdata_unlock(sdata);
}

struct sk_buff *ieee80211_ap_probereq_get(struct ieee80211_hw *hw,
					  struct ieee80211_vif *vif)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
	struct cfg80211_bss *cbss;


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