Backports v4.19.24

Backports generated by toradex backports 515a1fa55cda2b1d952872e1786857481bd54fcc
against mainline kernel tag v4.19.24

Signed-off-by: Dominik Sliwa <dominik.sliwa@toradex.com>

1 files changed, 1335 insertions, 0 deletions

diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
new file mode 100644
index 0000000..5d2a117
--- /dev/null
+++ b/net/mac80211/scan.c
@@ -0,0 +1,1335 @@
+/*
+ * Scanning implementation
+ *
+ * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.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 2013-2015  Intel Mobile Communications GmbH
+ * Copyright 2016-2017  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/if_arp.h>
+#include <linux/etherdevice.h>
+#include <linux/rtnetlink.h>
+#include <net/sch_generic.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+#include <linux/random.h>
+#include <net/mac80211.h>
+
+#include "ieee80211_i.h"
+#include "driver-ops.h"
+#include "mesh.h"
+
+#define IEEE80211_PROBE_DELAY (HZ / 33)
+#define IEEE80211_CHANNEL_TIME (HZ / 33)
+#define IEEE80211_PASSIVE_CHANNEL_TIME (HZ / 9)
+
+void ieee80211_rx_bss_put(struct ieee80211_local *local,
+			  struct ieee80211_bss *bss)
+{
+	if (!bss)
+		return;
+	cfg80211_put_bss(local->hw.wiphy,
+			 container_of((void *)bss, struct cfg80211_bss, priv));
+}
+
+static bool is_uapsd_supported(struct ieee802_11_elems *elems)
+{
+	u8 qos_info;
+
+	if (elems->wmm_info && elems->wmm_info_len == 7
+	    && elems->wmm_info[5] == 1)
+		qos_info = elems->wmm_info[6];
+	else if (elems->wmm_param && elems->wmm_param_len == 24
+		 && elems->wmm_param[5] == 1)
+		qos_info = elems->wmm_param[6];
+	else
+		/* no valid wmm information or parameter element found */
+		return false;
+
+	return qos_info & IEEE80211_WMM_IE_AP_QOSINFO_UAPSD;
+}
+
+struct ieee80211_bss *
+ieee80211_bss_info_update(struct ieee80211_local *local,
+			  struct ieee80211_rx_status *rx_status,
+			  struct ieee80211_mgmt *mgmt, size_t len,
+			  struct ieee802_11_elems *elems,
+			  struct ieee80211_channel *channel)
+{
+	bool beacon = ieee80211_is_beacon(mgmt->frame_control);
+	struct cfg80211_bss *cbss;
+	struct ieee80211_bss *bss;
+	int clen, srlen;
+	struct cfg80211_inform_bss bss_meta = {
+		.boottime_ns = rx_status->boottime_ns,
+	};
+	bool signal_valid;
+	struct ieee80211_sub_if_data *scan_sdata;
+
+	if (rx_status->flag & RX_FLAG_NO_SIGNAL_VAL)
+		bss_meta.signal = 0; /* invalid signal indication */
+	else if (ieee80211_hw_check(&local->hw, SIGNAL_DBM))
+		bss_meta.signal = rx_status->signal * 100;
+	else if (ieee80211_hw_check(&local->hw, SIGNAL_UNSPEC))
+		bss_meta.signal = (rx_status->signal * 100) / local->hw.max_signal;
+
+	bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_20;
+	if (rx_status->bw == RATE_INFO_BW_5)
+		bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_5;
+	else if (rx_status->bw == RATE_INFO_BW_10)
+		bss_meta.scan_width = NL80211_BSS_CHAN_WIDTH_10;
+
+	bss_meta.chan = channel;
+
+	rcu_read_lock();
+	scan_sdata = rcu_dereference(local->scan_sdata);
+	if (scan_sdata && scan_sdata->vif.type == NL80211_IFTYPE_STATION &&
+	    scan_sdata->vif.bss_conf.assoc &&
+	    ieee80211_have_rx_timestamp(rx_status)) {
+		bss_meta.parent_tsf =
+			ieee80211_calculate_rx_timestamp(local, rx_status,
+							 len + FCS_LEN, 24);
+		ether_addr_copy(bss_meta.parent_bssid,
+				scan_sdata->vif.bss_conf.bssid);
+	}
+	rcu_read_unlock();
+
+	cbss = cfg80211_inform_bss_frame_data(local->hw.wiphy, &bss_meta,
+					      mgmt, len, GFP_ATOMIC);
+	if (!cbss)
+		return NULL;
+	/* In case the signal is invalid update the status */
+	signal_valid = abs(channel->center_freq - cbss->channel->center_freq)
+		<= local->hw.wiphy->max_adj_channel_rssi_comp;
+	if (!signal_valid)
+		rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
+
+	bss = (void *)cbss->priv;
+
+	if (beacon)
+		bss->device_ts_beacon = rx_status->device_timestamp;
+	else
+		bss->device_ts_presp = rx_status->device_timestamp;
+
+	if (elems->parse_error) {
+		if (beacon)
+			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_BEACON;
+		else
+			bss->corrupt_data |= IEEE80211_BSS_CORRUPT_PROBE_RESP;
+	} else {
+		if (beacon)
+			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_BEACON;
+		else
+			bss->corrupt_data &= ~IEEE80211_BSS_CORRUPT_PROBE_RESP;
+	}
+
+	/* save the ERP value so that it is available at association time */
+	if (elems->erp_info && (!elems->parse_error ||
+				!(bss->valid_data & IEEE80211_BSS_VALID_ERP))) {
+		bss->erp_value = elems->erp_info[0];
+		bss->has_erp_value = true;
+		if (!elems->parse_error)
+			bss->valid_data |= IEEE80211_BSS_VALID_ERP;
+	}
+
+	/* replace old supported rates if we get new values */
+	if (!elems->parse_error ||
+	    !(bss->valid_data & IEEE80211_BSS_VALID_RATES)) {
+		srlen = 0;
+		if (elems->supp_rates) {
+			clen = IEEE80211_MAX_SUPP_RATES;
+			if (clen > elems->supp_rates_len)
+				clen = elems->supp_rates_len;
+			memcpy(bss->supp_rates, elems->supp_rates, clen);
+			srlen += clen;
+		}
+		if (elems->ext_supp_rates) {
+			clen = IEEE80211_MAX_SUPP_RATES - srlen;
+			if (clen > elems->ext_supp_rates_len)
+				clen = elems->ext_supp_rates_len;
+			memcpy(bss->supp_rates + srlen, elems->ext_supp_rates,
+			       clen);
+			srlen += clen;
+		}
+		if (srlen) {
+			bss->supp_rates_len = srlen;
+			if (!elems->parse_error)
+				bss->valid_data |= IEEE80211_BSS_VALID_RATES;
+		}
+	}
+
+	if (!elems->parse_error ||
+	    !(bss->valid_data & IEEE80211_BSS_VALID_WMM)) {
+		bss->wmm_used = elems->wmm_param || elems->wmm_info;
+		bss->uapsd_supported = is_uapsd_supported(elems);
+		if (!elems->parse_error)
+			bss->valid_data |= IEEE80211_BSS_VALID_WMM;
+	}
+
+	if (beacon) {
+		struct ieee80211_supported_band *sband =
+			local->hw.wiphy->bands[rx_status->band];
+		if (!(rx_status->encoding == RX_ENC_HT) &&
+		    !(rx_status->encoding == RX_ENC_VHT))
+			bss->beacon_rate =
+				&sband->bitrates[rx_status->rate_idx];
+	}
+
+	return bss;
+}
+
+static bool ieee80211_scan_accept_presp(struct ieee80211_sub_if_data *sdata,
+					u32 scan_flags, const u8 *da)
+{
+	if (!sdata)
+		return false;
+	/* accept broadcast for OCE */
+	if (scan_flags & NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP &&
+	    is_broadcast_ether_addr(da))
+		return true;
+	if (scan_flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
+		return true;
+	return ether_addr_equal(da, sdata->vif.addr);
+}
+
+void ieee80211_scan_rx(struct ieee80211_local *local, struct sk_buff *skb)
+{
+	struct ieee80211_rx_status *rx_status = IEEE80211_SKB_RXCB(skb);
+	struct ieee80211_sub_if_data *sdata1, *sdata2;
+	struct ieee80211_mgmt *mgmt = (void *)skb->data;
+	struct ieee80211_bss *bss;
+	u8 *elements;
+	struct ieee80211_channel *channel;
+	size_t baselen;
+	struct ieee802_11_elems elems;
+
+	if (skb->len < 24 ||
+	    (!ieee80211_is_probe_resp(mgmt->frame_control) &&
+	     !ieee80211_is_beacon(mgmt->frame_control)))
+		return;
+
+	sdata1 = rcu_dereference(local->scan_sdata);
+	sdata2 = rcu_dereference(local->sched_scan_sdata);
+
+	if (likely(!sdata1 && !sdata2))
+		return;
+
+	if (ieee80211_is_probe_resp(mgmt->frame_control)) {
+		struct cfg80211_scan_request *scan_req;
+		struct cfg80211_sched_scan_request *sched_scan_req;
+		u32 scan_req_flags = 0, sched_scan_req_flags = 0;
+
+		scan_req = rcu_dereference(local->scan_req);
+		sched_scan_req = rcu_dereference(local->sched_scan_req);
+
+		if (scan_req)
+			scan_req_flags = scan_req->flags;
+
+		if (sched_scan_req)
+			sched_scan_req_flags = sched_scan_req->flags;
+
+		/* ignore ProbeResp to foreign address or non-bcast (OCE)
+		 * unless scanning with randomised address
+		 */
+		if (!ieee80211_scan_accept_presp(sdata1, scan_req_flags,
+						 mgmt->da) &&
+		    !ieee80211_scan_accept_presp(sdata2, sched_scan_req_flags,
+						 mgmt->da))
+			return;
+
+		elements = mgmt->u.probe_resp.variable;
+		baselen = offsetof(struct ieee80211_mgmt, u.probe_resp.variable);
+	} else {
+		baselen = offsetof(struct ieee80211_mgmt, u.beacon.variable);
+		elements = mgmt->u.beacon.variable;
+	}
+
+	if (baselen > skb->len)
+		return;
+
+	ieee802_11_parse_elems(elements, skb->len - baselen, false, &elems);
+
+	channel = ieee80211_get_channel(local->hw.wiphy, rx_status->freq);
+
+	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
+		return;
+
+	bss = ieee80211_bss_info_update(local, rx_status,
+					mgmt, skb->len, &elems,
+					channel);
+	if (bss)
+		ieee80211_rx_bss_put(local, bss);
+}
+
+static void
+ieee80211_prepare_scan_chandef(struct cfg80211_chan_def *chandef,
+			       enum nl80211_bss_scan_width scan_width)
+{
+	memset(chandef, 0, sizeof(*chandef));
+	switch (scan_width) {
+	case NL80211_BSS_CHAN_WIDTH_5:
+		chandef->width = NL80211_CHAN_WIDTH_5;
+		break;
+	case NL80211_BSS_CHAN_WIDTH_10:
+		chandef->width = NL80211_CHAN_WIDTH_10;
+		break;
+	default:
+		chandef->width = NL80211_CHAN_WIDTH_20_NOHT;
+		break;
+	}
+}
+
+/* return false if no more work */
+static bool ieee80211_prep_hw_scan(struct ieee80211_local *local)
+{
+	struct cfg80211_scan_request *req;
+	struct cfg80211_chan_def chandef;
+	u8 bands_used = 0;
+	int i, ielen, n_chans;
+	u32 flags = 0;
+
+	req = rcu_dereference_protected(local->scan_req,
+					lockdep_is_held(&local->mtx));
+
+	if (test_bit(SCAN_HW_CANCELLED, &local->scanning))
+		return false;
+
+	if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
+		for (i = 0; i < req->n_channels; i++) {
+			local->hw_scan_req->req.channels[i] = req->channels[i];
+			bands_used |= BIT(req->channels[i]->band);
+		}
+
+		n_chans = req->n_channels;
+	} else {
+		do {
+			if (local->hw_scan_band == NUM_NL80211_BANDS)
+				return false;
+
+			n_chans = 0;
+
+			for (i = 0; i < req->n_channels; i++) {
+				if (req->channels[i]->band !=
+				    local->hw_scan_band)
+					continue;
+				local->hw_scan_req->req.channels[n_chans] =
+							req->channels[i];
+				n_chans++;
+				bands_used |= BIT(req->channels[i]->band);
+			}
+
+			local->hw_scan_band++;
+		} while (!n_chans);
+	}
+
+	local->hw_scan_req->req.n_channels = n_chans;
+	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
+
+	if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
+		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
+
+	ielen = ieee80211_build_preq_ies(local,
+					 (u8 *)local->hw_scan_req->req.ie,
+					 local->hw_scan_ies_bufsize,
+					 &local->hw_scan_req->ies,
+					 req->ie, req->ie_len,
+					 bands_used, req->rates, &chandef,
+					 flags);
+	local->hw_scan_req->req.ie_len = ielen;
+	local->hw_scan_req->req.no_cck = req->no_cck;
+	ether_addr_copy(local->hw_scan_req->req.mac_addr, req->mac_addr);
+	ether_addr_copy(local->hw_scan_req->req.mac_addr_mask,
+			req->mac_addr_mask);
+	ether_addr_copy(local->hw_scan_req->req.bssid, req->bssid);
+
+	return true;
+}
+
+static void __ieee80211_scan_completed(struct ieee80211_hw *hw, bool aborted)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+	bool hw_scan = local->ops->hw_scan;
+	bool was_scanning = local->scanning;
+	struct cfg80211_scan_request *scan_req;
+	struct ieee80211_sub_if_data *scan_sdata;
+	struct ieee80211_sub_if_data *sdata;
+
+	lockdep_assert_held(&local->mtx);
+
+	/*
+	 * It's ok to abort a not-yet-running scan (that
+	 * we have one at all will be verified by checking
+	 * local->scan_req next), but not to complete it
+	 * successfully.
+	 */
+	if (WARN_ON(!local->scanning && !aborted))
+		aborted = true;
+
+	if (WARN_ON(!local->scan_req))
+		return;
+
+	if (hw_scan && !aborted &&
+	    !ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS) &&
+	    ieee80211_prep_hw_scan(local)) {
+		int rc;
+
+		rc = drv_hw_scan(local,
+			rcu_dereference_protected(local->scan_sdata,
+						  lockdep_is_held(&local->mtx)),
+			local->hw_scan_req);
+
+		if (rc == 0)
+			return;
+
+		/* HW scan failed and is going to be reported as aborted,
+		 * so clear old scan info.
+		 */
+		memset(&local->scan_info, 0, sizeof(local->scan_info));
+		aborted = true;
+	}
+
+	kfree(local->hw_scan_req);
+	local->hw_scan_req = NULL;
+
+	scan_req = rcu_dereference_protected(local->scan_req,
+					     lockdep_is_held(&local->mtx));
+
+	if (scan_req != local->int_scan_req) {
+		local->scan_info.aborted = aborted;
+		cfg80211_scan_done(scan_req, &local->scan_info);
+	}
+	RCU_INIT_POINTER(local->scan_req, NULL);
+
+	scan_sdata = rcu_dereference_protected(local->scan_sdata,
+					       lockdep_is_held(&local->mtx));
+	RCU_INIT_POINTER(local->scan_sdata, NULL);
+
+	local->scanning = 0;
+	local->scan_chandef.chan = NULL;
+
+	/* Set power back to normal operating levels. */
+	ieee80211_hw_config(local, 0);
+
+	if (!hw_scan) {
+		ieee80211_configure_filter(local);
+		drv_sw_scan_complete(local, scan_sdata);
+		ieee80211_offchannel_return(local);
+	}
+
+	ieee80211_recalc_idle(local);
+
+	ieee80211_mlme_notify_scan_completed(local);
+	ieee80211_ibss_notify_scan_completed(local);
+
+	/* Requeue all the work that might have been ignored while
+	 * the scan was in progress; if there was none this will
+	 * just be a no-op for the particular interface.
+	 */
+	list_for_each_entry_rcu(sdata, &local->interfaces, list) {
+		if (ieee80211_sdata_running(sdata))
+			ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+	}
+
+	if (was_scanning)
+		ieee80211_start_next_roc(local);
+}
+
+void ieee80211_scan_completed(struct ieee80211_hw *hw,
+			      struct cfg80211_scan_info *info)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+
+	trace_api_scan_completed(local, info->aborted);
+
+	set_bit(SCAN_COMPLETED, &local->scanning);
+	if (info->aborted)
+		set_bit(SCAN_ABORTED, &local->scanning);
+
+	memcpy(&local->scan_info, info, sizeof(*info));
+
+	ieee80211_queue_delayed_work(&local->hw, &local->scan_work, 0);
+}
+EXPORT_SYMBOL(ieee80211_scan_completed);
+
+static int ieee80211_start_sw_scan(struct ieee80211_local *local,
+				   struct ieee80211_sub_if_data *sdata)
+{
+	/* Software scan is not supported in multi-channel cases */
+	if (local->use_chanctx)
+		return -EOPNOTSUPP;
+
+	/*
+	 * Hardware/driver doesn't support hw_scan, so use software
+	 * scanning instead. First send a nullfunc frame with power save
+	 * bit on so that AP will buffer the frames for us while we are not
+	 * listening, then send probe requests to each channel and wait for
+	 * the responses. After all channels are scanned, tune back to the
+	 * original channel and send a nullfunc frame with power save bit
+	 * off to trigger the AP to send us all the buffered frames.
+	 *
+	 * Note that while local->sw_scanning is true everything else but
+	 * nullfunc frames and probe requests will be dropped in
+	 * ieee80211_tx_h_check_assoc().
+	 */
+	drv_sw_scan_start(local, sdata, local->scan_addr);
+
+	local->leave_oper_channel_time = jiffies;
+	local->next_scan_state = SCAN_DECISION;
+	local->scan_channel_idx = 0;
+
+	ieee80211_offchannel_stop_vifs(local);
+
+	/* ensure nullfunc is transmitted before leaving operating channel */
+	ieee80211_flush_queues(local, NULL, false);
+
+	ieee80211_configure_filter(local);
+
+	/* We need to set power level at maximum rate for scanning. */
+	ieee80211_hw_config(local, 0);
+
+	ieee80211_queue_delayed_work(&local->hw,
+				     &local->scan_work, 0);
+
+	return 0;
+}
+
+static bool ieee80211_can_scan(struct ieee80211_local *local,
+			       struct ieee80211_sub_if_data *sdata)
+{
+	if (ieee80211_is_radar_required(local))
+		return false;
+
+	if (!list_empty(&local->roc_list))
+		return false;
+
+	if (sdata->vif.type == NL80211_IFTYPE_STATION &&
+	    sdata->u.mgd.flags & IEEE80211_STA_CONNECTION_POLL)
+		return false;
+
+	return true;
+}
+
+void ieee80211_run_deferred_scan(struct ieee80211_local *local)
+{
+	lockdep_assert_held(&local->mtx);
+
+	if (!local->scan_req || local->scanning)
+		return;
+
+	if (!ieee80211_can_scan(local,
+				rcu_dereference_protected(
+					local->scan_sdata,
+					lockdep_is_held(&local->mtx))))
+		return;
+
+	ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
+				     round_jiffies_relative(0));
+}
+
+static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
+					  const u8 *src, const u8 *dst,
+					  const u8 *ssid, size_t ssid_len,
+					  const u8 *ie, size_t ie_len,
+					  u32 ratemask, u32 flags, u32 tx_flags,
+					  struct ieee80211_channel *channel)
+{
+	struct sk_buff *skb;
+	u32 txdata_flags = 0;
+
+	skb = ieee80211_build_probe_req(sdata, src, dst, ratemask, channel,
+					ssid, ssid_len,
+					ie, ie_len, flags);
+
+	if (skb) {
+		if (flags & IEEE80211_PROBE_FLAG_RANDOM_SN) {
+			struct ieee80211_hdr *hdr = (void *)skb->data;
+			u16 sn = get_random_u32();
+
+			txdata_flags |= IEEE80211_TX_NO_SEQNO;
+			hdr->seq_ctrl =
+				cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
+		}
+		IEEE80211_SKB_CB(skb)->flags |= tx_flags;
+		ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band,
+					  txdata_flags);
+	}
+}
+
+static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
+					    unsigned long *next_delay)
+{
+	int i;
+	struct ieee80211_sub_if_data *sdata;
+	struct cfg80211_scan_request *scan_req;
+	enum nl80211_band band = local->hw.conf.chandef.chan->band;
+	u32 flags = 0, tx_flags;
+
+	scan_req = rcu_dereference_protected(local->scan_req,
+					     lockdep_is_held(&local->mtx));
+
+	tx_flags = IEEE80211_TX_INTFL_OFFCHAN_TX_OK;
+	if (scan_req->no_cck)
+		tx_flags |= IEEE80211_TX_CTL_NO_CCK_RATE;
+	if (scan_req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
+		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
+	if (scan_req->flags & NL80211_SCAN_FLAG_RANDOM_SN)
+		flags |= IEEE80211_PROBE_FLAG_RANDOM_SN;
+
+	sdata = rcu_dereference_protected(local->scan_sdata,
+					  lockdep_is_held(&local->mtx));
+
+	for (i = 0; i < scan_req->n_ssids; i++)
+		ieee80211_send_scan_probe_req(
+			sdata, local->scan_addr, scan_req->bssid,
+			scan_req->ssids[i].ssid, scan_req->ssids[i].ssid_len,
+			scan_req->ie, scan_req->ie_len,
+			scan_req->rates[band], flags,
+			tx_flags, local->hw.conf.chandef.chan);
+
+	/*
+	 * After sending probe requests, wait for probe responses
+	 * on the channel.
+	 */
+	*next_delay = IEEE80211_CHANNEL_TIME;
+	local->next_scan_state = SCAN_DECISION;
+}
+
+static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
+				  struct cfg80211_scan_request *req)
+{
+	struct ieee80211_local *local = sdata->local;
+	int rc;
+
+	lockdep_assert_held(&local->mtx);
+
+	if (local->scan_req || ieee80211_is_radar_required(local))
+		return -EBUSY;
+
+	if (!ieee80211_can_scan(local, sdata)) {
+		/* wait for the work to finish/time out */
+		rcu_assign_pointer(local->scan_req, req);
+		rcu_assign_pointer(local->scan_sdata, sdata);
+		return 0;
+	}
+
+	if (local->ops->hw_scan) {
+		u8 *ies;
+
+		local->hw_scan_ies_bufsize = local->scan_ies_len + req->ie_len;
+
+		if (ieee80211_hw_check(&local->hw, SINGLE_SCAN_ON_ALL_BANDS)) {
+			int i, n_bands = 0;
+			u8 bands_counted = 0;
+
+			for (i = 0; i < req->n_channels; i++) {
+				if (bands_counted & BIT(req->channels[i]->band))
+					continue;
+				bands_counted |= BIT(req->channels[i]->band);
+				n_bands++;
+			}
+
+			local->hw_scan_ies_bufsize *= n_bands;
+		}
+
+		local->hw_scan_req = kmalloc(
+				sizeof(*local->hw_scan_req) +
+				req->n_channels * sizeof(req->channels[0]) +
+				local->hw_scan_ies_bufsize, GFP_KERNEL);
+		if (!local->hw_scan_req)
+			return -ENOMEM;
+
+		local->hw_scan_req->req.ssids = req->ssids;
+		local->hw_scan_req->req.n_ssids = req->n_ssids;
+		ies = (u8 *)local->hw_scan_req +
+			sizeof(*local->hw_scan_req) +
+			req->n_channels * sizeof(req->channels[0]);
+		local->hw_scan_req->req.ie = ies;
+		local->hw_scan_req->req.flags = req->flags;
+		eth_broadcast_addr(local->hw_scan_req->req.bssid);
+		local->hw_scan_req->req.duration = req->duration;
+		local->hw_scan_req->req.duration_mandatory =
+			req->duration_mandatory;
+
+		local->hw_scan_band = 0;
+
+		/*
+		 * After allocating local->hw_scan_req, we must
+		 * go through until ieee80211_prep_hw_scan(), so
+		 * anything that might be changed here and leave
+		 * this function early must not go after this
+		 * allocation.
+		 */
+	}
+
+	rcu_assign_pointer(local->scan_req, req);
+	rcu_assign_pointer(local->scan_sdata, sdata);
+
+	if (req->flags & NL80211_SCAN_FLAG_RANDOM_ADDR)
+		get_random_mask_addr(local->scan_addr,
+				     req->mac_addr,
+				     req->mac_addr_mask);
+	else
+		memcpy(local->scan_addr, sdata->vif.addr, ETH_ALEN);
+
+	if (local->ops->hw_scan) {
+		__set_bit(SCAN_HW_SCANNING, &local->scanning);
+	} else if ((req->n_channels == 1) &&
+		   (req->channels[0] == local->_oper_chandef.chan)) {
+		/*
+		 * If we are scanning only on the operating channel
+		 * then we do not need to stop normal activities
+		 */
+		unsigned long next_delay;
+
+		__set_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning);
+
+		ieee80211_recalc_idle(local);
+
+		/* Notify driver scan is starting, keep order of operations
+		 * same as normal software scan, in case that matters. */
+		drv_sw_scan_start(local, sdata, local->scan_addr);
+
+		ieee80211_configure_filter(local); /* accept probe-responses */
+
+		/* We need to ensure power level is at max for scanning. */
+		ieee80211_hw_config(local, 0);
+
+		if ((req->channels[0]->flags & (IEEE80211_CHAN_NO_IR |
+						IEEE80211_CHAN_RADAR)) ||
+		    !req->n_ssids) {
+			next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
+		} else {
+			ieee80211_scan_state_send_probe(local, &next_delay);
+			next_delay = IEEE80211_CHANNEL_TIME;
+		}
+
+		/* Now, just wait a bit and we are all done! */
+		ieee80211_queue_delayed_work(&local->hw, &local->scan_work,
+					     next_delay);
+		return 0;
+	} else {
+		/* Do normal software scan */
+		__set_bit(SCAN_SW_SCANNING, &local->scanning);
+	}
+
+	ieee80211_recalc_idle(local);
+
+	if (local->ops->hw_scan) {
+		WARN_ON(!ieee80211_prep_hw_scan(local));
+		rc = drv_hw_scan(local, sdata, local->hw_scan_req);
+	} else {
+		rc = ieee80211_start_sw_scan(local, sdata);
+	}
+
+	if (rc) {
+		kfree(local->hw_scan_req);
+		local->hw_scan_req = NULL;
+		local->scanning = 0;
+
+		ieee80211_recalc_idle(local);
+
+		local->scan_req = NULL;
+		RCU_INIT_POINTER(local->scan_sdata, NULL);
+	}
+
+	return rc;
+}
+
+static unsigned long
+ieee80211_scan_get_channel_time(struct ieee80211_channel *chan)
+{
+	/*
+	 * TODO: channel switching also consumes quite some time,
+	 * add that delay as well to get a better estimation
+	 */
+	if (chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR))
+		return IEEE80211_PASSIVE_CHANNEL_TIME;
+	return IEEE80211_PROBE_DELAY + IEEE80211_CHANNEL_TIME;
+}
+
+static void ieee80211_scan_state_decision(struct ieee80211_local *local,
+					  unsigned long *next_delay)
+{
+	bool associated = false;
+	bool tx_empty = true;
+	bool bad_latency;
+	struct ieee80211_sub_if_data *sdata;
+	struct ieee80211_channel *next_chan;
+	enum mac80211_scan_state next_scan_state;
+	struct cfg80211_scan_request *scan_req;
+
+	/*
+	 * check if at least one STA interface is associated,
+	 * check if at least one STA interface has pending tx frames
+	 * and grab the lowest used beacon interval
+	 */
+	mutex_lock(&local->iflist_mtx);
+	list_for_each_entry(sdata, &local->interfaces, list) {
+		if (!ieee80211_sdata_running(sdata))
+			continue;
+
+		if (sdata->vif.type == NL80211_IFTYPE_STATION) {
+			if (sdata->u.mgd.associated) {
+				associated = true;
+
+				if (!qdisc_all_tx_empty(sdata->dev)) {
+					tx_empty = false;
+					break;
+				}
+			}
+		}
+	}
+	mutex_unlock(&local->iflist_mtx);
+
+	scan_req = rcu_dereference_protected(local->scan_req,
+					     lockdep_is_held(&local->mtx));
+
+	next_chan = scan_req->channels[local->scan_channel_idx];
+
+	/*
+	 * we're currently scanning a different channel, let's
+	 * see if we can scan another channel without interfering
+	 * with the current traffic situation.
+	 *
+	 * Keep good latency, do not stay off-channel more than 125 ms.
+	 */
+
+	bad_latency = time_after(jiffies +
+				 ieee80211_scan_get_channel_time(next_chan),
+				 local->leave_oper_channel_time + HZ / 8);
+
+	if (associated && !tx_empty) {
+		if (scan_req->flags & NL80211_SCAN_FLAG_LOW_PRIORITY)
+			next_scan_state = SCAN_ABORT;
+		else
+			next_scan_state = SCAN_SUSPEND;
+	} else if (associated && bad_latency) {
+		next_scan_state = SCAN_SUSPEND;
+	} else {
+		next_scan_state = SCAN_SET_CHANNEL;
+	}
+
+	local->next_scan_state = next_scan_state;
+
+	*next_delay = 0;
+}
+
+static void ieee80211_scan_state_set_channel(struct ieee80211_local *local,
+					     unsigned long *next_delay)
+{
+	int skip;
+	struct ieee80211_channel *chan;
+	enum nl80211_bss_scan_width oper_scan_width;
+	struct cfg80211_scan_request *scan_req;
+
+	scan_req = rcu_dereference_protected(local->scan_req,
+					     lockdep_is_held(&local->mtx));
+
+	skip = 0;
+	chan = scan_req->channels[local->scan_channel_idx];
+
+	local->scan_chandef.chan = chan;
+	local->scan_chandef.center_freq1 = chan->center_freq;
+	local->scan_chandef.center_freq2 = 0;
+	switch (scan_req->scan_width) {
+	case NL80211_BSS_CHAN_WIDTH_5:
+		local->scan_chandef.width = NL80211_CHAN_WIDTH_5;
+		break;
+	case NL80211_BSS_CHAN_WIDTH_10:
+		local->scan_chandef.width = NL80211_CHAN_WIDTH_10;
+		break;
+	case NL80211_BSS_CHAN_WIDTH_20:
+		/* If scanning on oper channel, use whatever channel-type
+		 * is currently in use.
+		 */
+		oper_scan_width = cfg80211_chandef_to_scan_width(
+					&local->_oper_chandef);
+		if (chan == local->_oper_chandef.chan &&
+		    oper_scan_width == scan_req->scan_width)
+			local->scan_chandef = local->_oper_chandef;
+		else
+			local->scan_chandef.width = NL80211_CHAN_WIDTH_20_NOHT;
+		break;
+	}
+
+	if (ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL))
+		skip = 1;
+
+	/* advance state machine to next channel/band */
+	local->scan_channel_idx++;
+
+	if (skip) {
+		/* if we skip this channel return to the decision state */
+		local->next_scan_state = SCAN_DECISION;
+		return;
+	}
+
+	/*
+	 * Probe delay is used to update the NAV, cf. 11.1.3.2.2
+	 * (which unfortunately doesn't say _why_ step a) is done,
+	 * but it waits for the probe delay or until a frame is
+	 * received - and the received frame would update the NAV).
+	 * For now, we do not support waiting until a frame is
+	 * received.
+	 *
+	 * In any case, it is not necessary for a passive scan.
+	 */
+	if ((chan->flags & (IEEE80211_CHAN_NO_IR | IEEE80211_CHAN_RADAR)) ||
+	    !scan_req->n_ssids) {
+		*next_delay = IEEE80211_PASSIVE_CHANNEL_TIME;
+		local->next_scan_state = SCAN_DECISION;
+		return;
+	}
+
+	/* active scan, send probes */
+	*next_delay = IEEE80211_PROBE_DELAY;
+	local->next_scan_state = SCAN_SEND_PROBE;
+}
+
+static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
+					 unsigned long *next_delay)
+{
+	/* switch back to the operating channel */
+	local->scan_chandef.chan = NULL;
+	ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL);
+
+	/* disable PS */
+	ieee80211_offchannel_return(local);
+
+	*next_delay = HZ / 5;
+	/* afterwards, resume scan & go to next channel */
+	local->next_scan_state = SCAN_RESUME;
+}
+
+static void ieee80211_scan_state_resume(struct ieee80211_local *local,
+					unsigned long *next_delay)
+{
+	ieee80211_offchannel_stop_vifs(local);
+
+	if (local->ops->flush) {
+		ieee80211_flush_queues(local, NULL, false);
+		*next_delay = 0;
+	} else
+		*next_delay = HZ / 10;
+
+	/* remember when we left the operating channel */
+	local->leave_oper_channel_time = jiffies;
+
+	/* advance to the next channel to be scanned */
+	local->next_scan_state = SCAN_SET_CHANNEL;
+}
+
+void ieee80211_scan_work(struct work_struct *work)
+{
+	struct ieee80211_local *local =
+		container_of(work, struct ieee80211_local, scan_work.work);
+	struct ieee80211_sub_if_data *sdata;
+	struct cfg80211_scan_request *scan_req;
+	unsigned long next_delay = 0;
+	bool aborted;
+
+	mutex_lock(&local->mtx);
+
+	if (!ieee80211_can_run_worker(local)) {
+		aborted = true;
+		goto out_complete;
+	}
+
+	sdata = rcu_dereference_protected(local->scan_sdata,
+					  lockdep_is_held(&local->mtx));
+	scan_req = rcu_dereference_protected(local->scan_req,
+					     lockdep_is_held(&local->mtx));
+
+	/* When scanning on-channel, the first-callback means completed. */
+	if (test_bit(SCAN_ONCHANNEL_SCANNING, &local->scanning)) {
+		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
+		goto out_complete;
+	}
+
+	if (test_and_clear_bit(SCAN_COMPLETED, &local->scanning)) {
+		aborted = test_and_clear_bit(SCAN_ABORTED, &local->scanning);
+		goto out_complete;
+	}
+
+	if (!sdata || !scan_req)
+		goto out;
+
+	if (!local->scanning) {
+		int rc;
+
+		RCU_INIT_POINTER(local->scan_req, NULL);
+		RCU_INIT_POINTER(local->scan_sdata, NULL);
+
+		rc = __ieee80211_start_scan(sdata, scan_req);
+		if (rc) {
+			/* need to complete scan in cfg80211 */
+			rcu_assign_pointer(local->scan_req, scan_req);
+			aborted = true;
+			goto out_complete;
+		} else
+			goto out;
+	}
+
+	/*
+	 * as long as no delay is required advance immediately
+	 * without scheduling a new work
+	 */
+	do {
+		if (!ieee80211_sdata_running(sdata)) {
+			aborted = true;
+			goto out_complete;
+		}
+
+		switch (local->next_scan_state) {
+		case SCAN_DECISION:
+			/* if no more bands/channels left, complete scan */
+			if (local->scan_channel_idx >= scan_req->n_channels) {
+				aborted = false;
+				goto out_complete;
+			}
+			ieee80211_scan_state_decision(local, &next_delay);
+			break;
+		case SCAN_SET_CHANNEL:
+			ieee80211_scan_state_set_channel(local, &next_delay);
+			break;
+		case SCAN_SEND_PROBE:
+			ieee80211_scan_state_send_probe(local, &next_delay);
+			break;
+		case SCAN_SUSPEND:
+			ieee80211_scan_state_suspend(local, &next_delay);
+			break;
+		case SCAN_RESUME:
+			ieee80211_scan_state_resume(local, &next_delay);
+			break;
+		case SCAN_ABORT:
+			aborted = true;
+			goto out_complete;
+		}
+	} while (next_delay == 0);
+
+	ieee80211_queue_delayed_work(&local->hw, &local->scan_work, next_delay);
+	goto out;
+
+out_complete:
+	__ieee80211_scan_completed(&local->hw, aborted);
+out:
+	mutex_unlock(&local->mtx);
+}
+
+int ieee80211_request_scan(struct ieee80211_sub_if_data *sdata,
+			   struct cfg80211_scan_request *req)
+{
+	int res;
+
+	mutex_lock(&sdata->local->mtx);
+	res = __ieee80211_start_scan(sdata, req);
+	mutex_unlock(&sdata->local->mtx);
+
+	return res;
+}
+
+int ieee80211_request_ibss_scan(struct ieee80211_sub_if_data *sdata,
+				const u8 *ssid, u8 ssid_len,
+				struct ieee80211_channel **channels,
+				unsigned int n_channels,
+				enum nl80211_bss_scan_width scan_width)
+{
+	struct ieee80211_local *local = sdata->local;
+	int ret = -EBUSY, i, n_ch = 0;
+	enum nl80211_band band;
+
+	mutex_lock(&local->mtx);
+
+	/* busy scanning */
+	if (local->scan_req)
+		goto unlock;
+
+	/* fill internal scan request */
+	if (!channels) {
+		int max_n;
+
+		for (band = 0; band < NUM_NL80211_BANDS; band++) {
+			if (!local->hw.wiphy->bands[band])
+				continue;
+
+			max_n = local->hw.wiphy->bands[band]->n_channels;
+			for (i = 0; i < max_n; i++) {
+				struct ieee80211_channel *tmp_ch =
+				    &local->hw.wiphy->bands[band]->channels[i];
+
+				if (tmp_ch->flags & (IEEE80211_CHAN_NO_IR |
+						     IEEE80211_CHAN_DISABLED))
+					continue;
+
+				local->int_scan_req->channels[n_ch] = tmp_ch;
+				n_ch++;
+			}
+		}
+
+		if (WARN_ON_ONCE(n_ch == 0))
+			goto unlock;
+
+		local->int_scan_req->n_channels = n_ch;
+	} else {
+		for (i = 0; i < n_channels; i++) {
+			if (channels[i]->flags & (IEEE80211_CHAN_NO_IR |
+						  IEEE80211_CHAN_DISABLED))
+				continue;
+
+			local->int_scan_req->channels[n_ch] = channels[i];
+			n_ch++;
+		}
+
+		if (WARN_ON_ONCE(n_ch == 0))
+			goto unlock;
+
+		local->int_scan_req->n_channels = n_ch;
+	}
+
+	local->int_scan_req->ssids = &local->scan_ssid;
+	local->int_scan_req->n_ssids = 1;
+	local->int_scan_req->scan_width = scan_width;
+	memcpy(local->int_scan_req->ssids[0].ssid, ssid, IEEE80211_MAX_SSID_LEN);
+	local->int_scan_req->ssids[0].ssid_len = ssid_len;
+
+	ret = __ieee80211_start_scan(sdata, sdata->local->int_scan_req);
+ unlock:
+	mutex_unlock(&local->mtx);
+	return ret;
+}
+
+/*
+ * Only call this function when a scan can't be queued -- under RTNL.
+ */
+void ieee80211_scan_cancel(struct ieee80211_local *local)
+{
+	/*
+	 * We are canceling software scan, or deferred scan that was not
+	 * yet really started (see __ieee80211_start_scan ).
+	 *
+	 * Regarding hardware scan:
+	 * - we can not call  __ieee80211_scan_completed() as when
+	 *   SCAN_HW_SCANNING bit is set this function change
+	 *   local->hw_scan_req to operate on 5G band, what race with
+	 *   driver which can use local->hw_scan_req
+	 *
+	 * - we can not cancel scan_work since driver can schedule it
+	 *   by ieee80211_scan_completed(..., true) to finish scan
+	 *
+	 * Hence we only call the cancel_hw_scan() callback, but the low-level
+	 * driver is still responsible for calling ieee80211_scan_completed()
+	 * after the scan was completed/aborted.
+	 */
+
+	mutex_lock(&local->mtx);
+	if (!local->scan_req)
+		goto out;
+
+	/*
+	 * We have a scan running and the driver already reported completion,
+	 * but the worker hasn't run yet or is stuck on the mutex - mark it as
+	 * cancelled.
+	 */
+	if (test_bit(SCAN_HW_SCANNING, &local->scanning) &&
+	    test_bit(SCAN_COMPLETED, &local->scanning)) {
+		set_bit(SCAN_HW_CANCELLED, &local->scanning);
+		goto out;
+	}
+
+	if (test_bit(SCAN_HW_SCANNING, &local->scanning)) {
+		/*
+		 * Make sure that __ieee80211_scan_completed doesn't trigger a
+		 * scan on another band.
+		 */
+		set_bit(SCAN_HW_CANCELLED, &local->scanning);
+		if (local->ops->cancel_hw_scan)
+			drv_cancel_hw_scan(local,
+				rcu_dereference_protected(local->scan_sdata,
+						lockdep_is_held(&local->mtx)));
+		goto out;
+	}
+
+	/*
+	 * If the work is currently running, it must be blocked on
+	 * the mutex, but we'll set scan_sdata = NULL and it'll
+	 * simply exit once it acquires the mutex.
+	 */
+	cancel_delayed_work(&local->scan_work);
+	/* and clean up */
+	memset(&local->scan_info, 0, sizeof(local->scan_info));
+	__ieee80211_scan_completed(&local->hw, true);
+out:
+	mutex_unlock(&local->mtx);
+}
+
+int __ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
+					struct cfg80211_sched_scan_request *req)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_scan_ies sched_scan_ies = {};
+	struct cfg80211_chan_def chandef;
+	int ret, i, iebufsz, num_bands = 0;
+	u32 rate_masks[NUM_NL80211_BANDS] = {};
+	u8 bands_used = 0;
+	u8 *ie;
+	u32 flags = 0;
+
+	iebufsz = local->scan_ies_len + req->ie_len;
+
+	lockdep_assert_held(&local->mtx);
+
+	if (!local->ops->sched_scan_start)
+		return -ENOTSUPP;
+
+	for (i = 0; i < NUM_NL80211_BANDS; i++) {
+		if (local->hw.wiphy->bands[i]) {
+			bands_used |= BIT(i);
+			rate_masks[i] = (u32) -1;
+			num_bands++;
+		}
+	}
+
+	if (req->flags & NL80211_SCAN_FLAG_MIN_PREQ_CONTENT)
+		flags |= IEEE80211_PROBE_FLAG_MIN_CONTENT;
+
+	ie = kcalloc(iebufsz, num_bands, GFP_KERNEL);
+	if (!ie) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ieee80211_prepare_scan_chandef(&chandef, req->scan_width);
+
+	ieee80211_build_preq_ies(local, ie, num_bands * iebufsz,
+				 &sched_scan_ies, req->ie,
+				 req->ie_len, bands_used, rate_masks, &chandef,
+				 flags);
+
+	ret = drv_sched_scan_start(local, sdata, req, &sched_scan_ies);
+	if (ret == 0) {
+		rcu_assign_pointer(local->sched_scan_sdata, sdata);
+		rcu_assign_pointer(local->sched_scan_req, req);
+	}
+
+	kfree(ie);
+
+out:
+	if (ret) {
+		/* Clean in case of failure after HW restart or upon resume. */
+		RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
+		RCU_INIT_POINTER(local->sched_scan_req, NULL);
+	}
+
+	return ret;
+}
+
+int ieee80211_request_sched_scan_start(struct ieee80211_sub_if_data *sdata,
+				       struct cfg80211_sched_scan_request *req)
+{
+	struct ieee80211_local *local = sdata->local;
+	int ret;
+
+	mutex_lock(&local->mtx);
+
+	if (rcu_access_pointer(local->sched_scan_sdata)) {
+		mutex_unlock(&local->mtx);
+		return -EBUSY;
+	}
+
+	ret = __ieee80211_request_sched_scan_start(sdata, req);
+
+	mutex_unlock(&local->mtx);
+	return ret;
+}
+
+int ieee80211_request_sched_scan_stop(struct ieee80211_local *local)
+{
+	struct ieee80211_sub_if_data *sched_scan_sdata;
+	int ret = -ENOENT;
+
+	mutex_lock(&local->mtx);
+
+	if (!local->ops->sched_scan_stop) {
+		ret = -ENOTSUPP;
+		goto out;
+	}
+
+	/* We don't want to restart sched scan anymore. */
+	RCU_INIT_POINTER(local->sched_scan_req, NULL);
+
+	sched_scan_sdata = rcu_dereference_protected(local->sched_scan_sdata,
+						lockdep_is_held(&local->mtx));
+	if (sched_scan_sdata) {
+		ret = drv_sched_scan_stop(local, sched_scan_sdata);
+		if (!ret)
+			RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
+	}
+out:
+	mutex_unlock(&local->mtx);
+
+	return ret;
+}
+
+void ieee80211_sched_scan_results(struct ieee80211_hw *hw)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+
+	trace_api_sched_scan_results(local);
+
+	cfg80211_sched_scan_results(hw->wiphy, 0);
+}
+EXPORT_SYMBOL(ieee80211_sched_scan_results);
+
+void ieee80211_sched_scan_end(struct ieee80211_local *local)
+{
+	mutex_lock(&local->mtx);
+
+	if (!rcu_access_pointer(local->sched_scan_sdata)) {
+		mutex_unlock(&local->mtx);
+		return;
+	}
+
+	RCU_INIT_POINTER(local->sched_scan_sdata, NULL);
+
+	/* If sched scan was aborted by the driver. */
+	RCU_INIT_POINTER(local->sched_scan_req, NULL);
+
+	mutex_unlock(&local->mtx);
+
+	cfg80211_sched_scan_stopped(local->hw.wiphy, 0);
+}
+
+void ieee80211_sched_scan_stopped_work(struct work_struct *work)
+{
+	struct ieee80211_local *local =
+		container_of(work, struct ieee80211_local,
+			     sched_scan_stopped_work);
+
+	ieee80211_sched_scan_end(local);
+}
+
+void ieee80211_sched_scan_stopped(struct ieee80211_hw *hw)
+{
+	struct ieee80211_local *local = hw_to_local(hw);
+
+	trace_api_sched_scan_stopped(local);
+
+	/*
+	 * this shouldn't really happen, so for simplicity
+	 * simply ignore it, and let mac80211 reconfigure
+	 * the sched scan later on.
+	 */
+	if (local->in_reconfig)
+		return;
+
+	schedule_work(&local->sched_scan_stopped_work);
+}
+EXPORT_SYMBOL(ieee80211_sched_scan_stopped);