struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
				       struct ieee80211_vif *vif,
				       bool qos_ok)
{
	struct ieee80211_hdr_3addr *nullfunc;
	struct ieee80211_sub_if_data *sdata;
	struct ieee80211_if_managed *ifmgd;
	struct ieee80211_local *local;
	struct sk_buff *skb;
	bool qos = false;

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

	sdata = vif_to_sdata(vif);
	ifmgd = &sdata->u.mgd;
	local = sdata->local;

	if (qos_ok) {
		struct sta_info *sta;

		rcu_read_lock();
		sta = sta_info_get(sdata, ifmgd->bssid);
		qos = sta && sta->sta.wme;
		rcu_read_unlock();
	}

	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
			    sizeof(*nullfunc) + 2);
	if (!skb)
		return NULL;

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

	nullfunc = skb_put_zero(skb, sizeof(*nullfunc));
	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
					      IEEE80211_STYPE_NULLFUNC |
					      IEEE80211_FCTL_TODS);
	if (qos) {
		__le16 qoshdr = cpu_to_le16(7);

		BUILD_BUG_ON((IEEE80211_STYPE_QOS_NULLFUNC |
			      IEEE80211_STYPE_NULLFUNC) !=
			     IEEE80211_STYPE_QOS_NULLFUNC);
		nullfunc->frame_control |=
			cpu_to_le16(IEEE80211_STYPE_QOS_NULLFUNC);
		skb->priority = 7;
		skb_set_queue_mapping(skb, IEEE80211_AC_VO);
		skb_put_data(skb, &qoshdr, sizeof(qoshdr));
	}

	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);

	return skb;
}
struct sk_buff *ieee80211_nullfunc_get(struct ieee80211_hw *hw,
				       struct ieee80211_vif *vif,
				       bool qos_ok)
{
	struct ieee80211_hdr_3addr *nullfunc;
	struct ieee80211_sub_if_data *sdata;
	struct ieee80211_if_managed *ifmgd;
	struct ieee80211_local *local;
	struct sk_buff *skb;
	bool qos = false;

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

	sdata = vif_to_sdata(vif);
	ifmgd = &sdata->u.mgd;
	local = sdata->local;

	if (qos_ok) {
		struct sta_info *sta;

		rcu_read_lock();
		sta = sta_info_get(sdata, ifmgd->bssid);
		qos = sta && sta->sta.wme;
		rcu_read_unlock();
	}

	skb = dev_alloc_skb(local->hw.extra_tx_headroom +
			    sizeof(*nullfunc) + 2);
	if (!skb)
		return NULL;

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

	nullfunc = skb_put_zero(skb, sizeof(*nullfunc));
	nullfunc->frame_control = cpu_to_le16(IEEE80211_FTYPE_DATA |
					      IEEE80211_STYPE_NULLFUNC |
					      IEEE80211_FCTL_TODS);
	if (qos) {
		__le16 qoshdr = cpu_to_le16(7);

		BUILD_BUG_ON((IEEE80211_STYPE_QOS_NULLFUNC |
			      IEEE80211_STYPE_NULLFUNC) !=
			     IEEE80211_STYPE_QOS_NULLFUNC);
		nullfunc->frame_control |=
			cpu_to_le16(IEEE80211_STYPE_QOS_NULLFUNC);
		skb->priority = 7;
		skb_set_queue_mapping(skb, IEEE80211_AC_VO);
		skb_put_data(skb, &qoshdr, sizeof(qoshdr));
	}

	memcpy(nullfunc->addr1, ifmgd->bssid, ETH_ALEN);
	memcpy(nullfunc->addr2, vif->addr, ETH_ALEN);
	memcpy(nullfunc->addr3, ifmgd->bssid, ETH_ALEN);

	return skb;
}