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

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The LITMUS^RT kernel.

Bjoern Brandenburg

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path: root/include/linux/mmc/card.h

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Diffstat (limited to 'include/linux/mmc/card.h')

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include/linux/mmc/card.h

1 files changed, 1 insertions, 1 deletions


diff --git a/include/linux/mmc/card.h b/include/linux/mmc/card.h index 4d69c00497bd..a6cf4c063e4e 100644 --- a/include/linux/mmc/card.h +++ b/include/linux/mmc/card.h
@@ -83,7 +83,7 @@ struct mmc_ext_csd {
83	bool hpi; /* HPI support bit */	83	bool hpi; /* HPI support bit */
84	unsigned int hpi_cmd; /* cmd used as HPI */	84	unsigned int hpi_cmd; /* cmd used as HPI */
85	bool bkops; /* background support bit */	85	bool bkops; /* background support bit */
86	bool bkops_en; /* background enable bit */	86	bool man_bkops_en; /* manual bkops enable bit */
87	unsigned int data_sector_size; /* 512 bytes or 4KB */	87	unsigned int data_sector_size; /* 512 bytes or 4KB */
88	unsigned int data_tag_unit_size; /* DATA TAG UNIT size */	88	unsigned int data_tag_unit_size; /* DATA TAG UNIT size */
89	unsigned int boot_ro_lock; /* ro lock support */	89	unsigned int boot_ro_lock; /* ro lock support */

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/*
 * cfg80211 scan result handling
 *
 * Copyright 2008 Johannes Berg <johannes@sipsolutions.net>
 * Copyright 2013-2014  Intel Mobile Communications GmbH
 */
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/netdevice.h>
#include <linux/wireless.h>
#include <linux/nl80211.h>
#include <linux/etherdevice.h>
#include <net/arp.h>
#include <net/cfg80211.h>
#include <net/cfg80211-wext.h>
#include <net/iw_handler.h>
#include "core.h"
#include "nl80211.h"
#include "wext-compat.h"
#include "rdev-ops.h"

/**
 * DOC: BSS tree/list structure
 *
 * At the top level, the BSS list is kept in both a list in each
 * registered device (@bss_list) as well as an RB-tree for faster
 * lookup. In the RB-tree, entries can be looked up using their
 * channel, MESHID, MESHCONF (for MBSSes) or channel, BSSID, SSID
 * for other BSSes.
 *
 * Due to the possibility of hidden SSIDs, there's a second level
 * structure, the "hidden_list" and "hidden_beacon_bss" pointer.
 * The hidden_list connects all BSSes belonging to a single AP
 * that has a hidden SSID, and connects beacon and probe response
 * entries. For a probe response entry for a hidden SSID, the
 * hidden_beacon_bss pointer points to the BSS struct holding the
 * beacon's information.
 *
 * Reference counting is done for all these references except for
 * the hidden_list, so that a beacon BSS struct that is otherwise
 * not referenced has one reference for being on the bss_list and
 * one for each probe response entry that points to it using the
 * hidden_beacon_bss pointer. When a BSS struct that has such a
 * pointer is get/put, the refcount update is also propagated to
 * the referenced struct, this ensure that it cannot get removed
 * while somebody is using the probe response version.
 *
 * Note that the hidden_beacon_bss pointer never changes, due to
 * the reference counting. Therefore, no locking is needed for
 * it.
 *
 * Also note that the hidden_beacon_bss pointer is only relevant
 * if the driver uses something other than the IEs, e.g. private
 * data stored stored in the BSS struct, since the beacon IEs are
 * also linked into the probe response struct.
 */

#define IEEE80211_SCAN_RESULT_EXPIRE	(30 * HZ)

static void bss_free(struct cfg80211_internal_bss *bss)
{
	struct cfg80211_bss_ies *ies;

	if (WARN_ON(atomic_read(&bss->hold)))
		return;

	ies = (void *)rcu_access_pointer(bss->pub.beacon_ies);
	if (ies && !bss->pub.hidden_beacon_bss)
		kfree_rcu(ies, rcu_head);
	ies = (void *)rcu_access_pointer(bss->pub.proberesp_ies);
	if (ies)
		kfree_rcu(ies, rcu_head);

	/*
	 * This happens when the module is removed, it doesn't
	 * really matter any more save for completeness
	 */
	if (!list_empty(&bss->hidden_list))
		list_del(&bss->hidden_list);

	kfree(bss);
}

static inline void bss_ref_get(struct cfg80211_registered_device *rdev,
			       struct cfg80211_internal_bss *bss)
{
	lockdep_assert_held(&rdev->bss_lock);

	bss->refcount++;
	if (bss->pub.hidden_beacon_bss) {
		bss = container_of(bss->pub.hidden_beacon_bss,
				   struct cfg80211_internal_bss,
				   pub);
		bss->refcount++;
	}
}

static inline void bss_ref_put(struct cfg80211_registered_device *rdev,
			       struct cfg80211_internal_bss *bss)
{
	lockdep_assert_held(&rdev->bss_lock);

	if (bss->pub.hidden_beacon_bss) {
		struct cfg80211_internal_bss *hbss;
		hbss = container_of(bss->pub.hidden_beacon_bss,
				    struct cfg80211_internal_bss,
				    pub);
		hbss->refcount--;
		if (hbss->refcount == 0)
			bss_free(hbss);
	}
	bss->refcount--;
	if (bss->refcount == 0)
		bss_free(bss);
}

static bool __cfg80211_unlink_bss(struct cfg80211_registered_device *rdev,
				  struct cfg80211_internal_bss *bss)
{
	lockdep_assert_held(&rdev->bss_lock);

	if (!list_empty(&bss->hidden_list)) {
		/*
		 * don't remove the beacon entry if it has
		 * probe responses associated with it
		 */
		if (!bss->pub.hidden_beacon_bss)
			return false;
		/*
		 * if it's a probe response entry break its
		 * link to the other entries in the group
		 */
		list_del_init(&bss->hidden_list);
	}

	list_del_init(&bss->list);
	rb_erase(&bss->rbn, &rdev->bss_tree);
	bss_ref_put(rdev, bss);
	return true;
}

static void __cfg80211_bss_expire(struct cfg80211_registered_device *rdev,
				  unsigned long expire_time)
{
	struct cfg80211_internal_bss *bss, *tmp;
	bool expired = false;

	lockdep_assert_held(&rdev->bss_lock);

	list_for_each_entry_safe(bss, tmp, &rdev->bss_list, list) {
		if (atomic_read(&bss->hold))
			continue;
		if (!time_after(expire_time, bss->ts))
			continue;

		if (__cfg80211_unlink_bss(rdev, bss))
			expired = true;
	}

	if (expired)
		rdev->bss_generation++;
}

void ___cfg80211_scan_done(struct cfg80211_registered_device *rdev,
			   bool send_message)
{
	struct cfg80211_scan_request *request;
	struct wireless_dev *wdev;
	struct sk_buff *msg;
#ifdef CONFIG_CFG80211_WEXT
	union iwreq_data wrqu;
#endif

	ASSERT_RTNL();

	if (rdev->scan_msg) {
		nl80211_send_scan_result(rdev, rdev->scan_msg);
		rdev->scan_msg = NULL;
		return;
	}

	request = rdev->scan_req;
	if (!request)
		return;

	wdev = request->wdev;

	/*
	 * This must be before sending the other events!
	 * Otherwise, wpa_supplicant gets completely confused with
	 * wext events.
	 */
	if (wdev->netdev)
		cfg80211_sme_scan_done(wdev->netdev);

	if (!request->aborted &&
	    request->flags & NL80211_SCAN_FLAG_FLUSH) {
		/* flush entries from previous scans */
		spin_lock_bh(&rdev->bss_lock);
		__cfg80211_bss_expire(rdev, request->scan_start);
		spin_unlock_bh(&rdev->bss_lock);
	}

	msg = nl80211_build_scan_msg(rdev, wdev, request->aborted);

#ifdef CONFIG_CFG80211_WEXT
	if (wdev->netdev && !request->aborted) {
		memset(&wrqu, 0, sizeof(wrqu));

		wireless_send_event(wdev->netdev, SIOCGIWSCAN, &wrqu, NULL);
	}
#endif

	if (wdev->netdev)
		dev_put(wdev->netdev);

	rdev->scan_req = NULL;
	kfree(request);

	if (!send_message)
		rdev->scan_msg = msg;
	else
		nl80211_send_scan_result(rdev, msg);
}

void __cfg80211_scan_done(struct work_struct *wk)
{
	struct cfg80211_registered_device *rdev;

	rdev = container_of(wk, struct cfg80211_registered_device,
			    scan_done_wk);

	rtnl_lock();
	___cfg80211_scan_done(rdev, true);
	rtnl_unlock();
}

void cfg80211_scan_done(struct cfg80211_scan_request *request, bool aborted)
{
	trace_cfg80211_scan_done(request, aborted);
	WARN_ON(request != wiphy_to_rdev(request->wiphy)->scan_req);

	request->aborted = aborted;
	request->notified = true;
	queue_work(cfg80211_wq, &wiphy_to_rdev(request->wiphy)->scan_done_wk);
}
EXPORT_SYMBOL(cfg80211_scan_done);

void __cfg80211_sched_scan_results(struct work_struct *wk)
{
	struct cfg80211_registered_device *rdev;
	struct cfg80211_sched_scan_request *request;

	rdev = container_of(wk, struct cfg80211_registered_device,
			    sched_scan_results_wk);

	rtnl_lock();

	request = rdev->sched_scan_req;

	/* we don't have sched_scan_req anymore if the scan is stopping */
	if (request) {
		if (request->flags & NL80211_SCAN_FLAG_FLUSH) {
			/* flush entries from previous scans */
			spin_lock_bh(&rdev->bss_lock);
			__cfg80211_bss_expire(rdev, request->scan_start);
			spin_unlock_bh(&rdev->bss_lock);
			request->scan_start =
				jiffies + msecs_to_jiffies(request->interval);
		}
		nl80211_send_sched_scan_results(rdev, request->dev);
	}

	rtnl_unlock();
}

void cfg80211_sched_scan_results(struct wiphy *wiphy)
{
	trace_cfg80211_sched_scan_results(wiphy);
	/* ignore if we're not scanning */
	if (wiphy_to_rdev(wiphy)->sched_scan_req)
		queue_work(cfg80211_wq,
			   &wiphy_to_rdev(wiphy)->sched_scan_results_wk);
}
EXPORT_SYMBOL(cfg80211_sched_scan_results);

void cfg80211_sched_scan_stopped_rtnl(struct wiphy *wiphy)
{
	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);

	ASSERT_RTNL();

	trace_cfg80211_sched_scan_stopped(wiphy);

	__cfg80211_stop_sched_scan(rdev, true);
}
EXPORT_SYMBOL(cfg80211_sched_scan_stopped_rtnl);

void cfg80211_sched_scan_stopped(struct wiphy *wiphy)
{
	rtnl_lock();
	cfg80211_sched_scan_stopped_rtnl(wiphy);
	rtnl_unlock();
}
EXPORT_SYMBOL(cfg80211_sched_scan_stopped);

int __cfg80211_stop_sched_scan(struct cfg80211_registered_device *rdev,
			       bool driver_initiated)
{
	struct net_device *dev;

	ASSERT_RTNL();

	if (!rdev->sched_scan_req)
		return -ENOENT;

	dev = rdev->sched_scan_req->dev;

	if (!driver_initiated) {
		int err = rdev_sched_scan_stop(rdev, dev);
		if (err)
			return err;
	}

	nl80211_send_sched_scan(rdev, dev, NL80211_CMD_SCHED_SCAN_STOPPED);

	kfree(rdev->sched_scan_req);
	rdev->sched_scan_req = NULL;

	return 0;
}

void cfg80211_bss_age(struct cfg80211_registered_device *rdev,
                      unsigned long age_secs)
{
	struct cfg80211_internal_bss *bss;
	unsigned long age_jiffies = msecs_to_jiffies(age_secs * MSEC_PER_SEC);

	spin_lock_bh(&rdev->bss_lock);
	list_for_each_entry(bss, &rdev->bss_list, list)
		bss->ts -= age_jiffies;
	spin_unlock_bh(&rdev->bss_lock);
}

void cfg80211_bss_expire(struct cfg80211_registered_device *rdev)
{
	__cfg80211_bss_expire(rdev, jiffies - IEEE80211_SCAN_RESULT_EXPIRE);
}

const u8 *cfg80211_find_ie(u8 eid, const u8 *ies, int len)
{
	while (len > 2 && ies[0] != eid) {
		len -= ies[1] + 2;
		ies += ies[1] + 2;
	}
	if (len < 2)
		return NULL;
	if (len < 2 + ies[1])
		return NULL;
	return ies;
}
EXPORT_SYMBOL(cfg80211_find_ie);

const u8 *cfg80211_find_vendor_ie(unsigned int oui, u8 oui_type,
				  const u8 *ies, int len)
{
	struct ieee80211_vendor_ie *ie;
	const u8 *pos = ies, *end = ies + len;
	int ie_oui;

	while (pos < end) {
		pos = cfg80211_find_ie(WLAN_EID_VENDOR_SPECIFIC, pos,
				       end - pos);
		if (!pos)
			return NULL;

		ie = (struct ieee80211_vendor_ie *)pos;

		/* make sure we can access ie->len */
		BUILD_BUG_ON(offsetof(struct ieee80211_vendor_ie, len) != 1);

		if (ie->len < sizeof(*ie))
			goto cont;

		ie_oui = ie->oui[0] << 16 | ie->oui[1] << 8 | ie->oui[2];
		if (ie_oui == oui && ie->oui_type == oui_type)
			return pos;
cont:
		pos += 2 + ie->len;
	}
	return NULL;
}
EXPORT_SYMBOL(cfg80211_find_vendor_ie);

static bool is_bss(struct cfg80211_bss *a, const u8 *bssid,
		   const u8 *ssid, size_t ssid_len)
{
	const struct cfg80211_bss_ies *ies;
	const u8 *ssidie;

	if (bssid && !ether_addr_equal(a->bssid, bssid))
		return false;

	if (!ssid)
		return true;

	ies = rcu_access_pointer(a->ies);
	if (!ies)
		return false;
	ssidie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
	if (!ssidie)
		return false;
	if (ssidie[1] != ssid_len)
		return false;
	return memcmp(ssidie + 2, ssid, ssid_len) == 0;
}

/**
 * enum bss_compare_mode - BSS compare mode
 * @BSS_CMP_REGULAR: regular compare mode (for insertion and normal find)
 * @BSS_CMP_HIDE_ZLEN: find hidden SSID with zero-length mode
 * @BSS_CMP_HIDE_NUL: find hidden SSID with NUL-ed out mode
 */
enum bss_compare_mode {
	BSS_CMP_REGULAR,
	BSS_CMP_HIDE_ZLEN,
	BSS_CMP_HIDE_NUL,
};

static int cmp_bss(struct cfg80211_bss *a,
		   struct cfg80211_bss *b,
		   enum bss_compare_mode mode)
{
	const struct cfg80211_bss_ies *a_ies, *b_ies;
	const u8 *ie1 = NULL;
	const u8 *ie2 = NULL;
	int i, r;

	if (a->channel != b->channel)
		return b->channel->center_freq - a->channel->center_freq;

	a_ies = rcu_access_pointer(a->ies);
	if (!a_ies)
		return -1;
	b_ies = rcu_access_pointer(b->ies);
	if (!b_ies)
		return 1;

	if (WLAN_CAPABILITY_IS_STA_BSS(a->capability))
		ie1 = cfg80211_find_ie(WLAN_EID_MESH_ID,
				       a_ies->data, a_ies->len);
	if (WLAN_CAPABILITY_IS_STA_BSS(b->capability))
		ie2 = cfg80211_find_ie(WLAN_EID_MESH_ID,
				       b_ies->data, b_ies->len);
	if (ie1 && ie2) {
		int mesh_id_cmp;

		if (ie1[1] == ie2[1])
			mesh_id_cmp = memcmp(ie1 + 2, ie2 + 2, ie1[1]);
		else
			mesh_id_cmp = ie2[1] - ie1[1];

		ie1 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
				       a_ies->data, a_ies->len);
		ie2 = cfg80211_find_ie(WLAN_EID_MESH_CONFIG,
				       b_ies->data, b_ies->len);
		if (ie1 && ie2) {
			if (mesh_id_cmp)
				return mesh_id_cmp;
			if (ie1[1] != ie2[1])
				return ie2[1] - ie1[1];
			return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
		}
	}

	r = memcmp(a->bssid, b->bssid, sizeof(a->bssid));
	if (r)
		return r;

	ie1 = cfg80211_find_ie(WLAN_EID_SSID, a_ies->data, a_ies->len);
	ie2 = cfg80211_find_ie(WLAN_EID_SSID, b_ies->data, b_ies->len);

	if (!ie1 && !ie2)
		return 0;

	/*
	 * Note that with "hide_ssid", the function returns a match if
	 * the already-present BSS ("b") is a hidden SSID beacon for
	 * the new BSS ("a").
	 */

	/* sort missing IE before (left of) present IE */
	if (!ie1)
		return -1;
	if (!ie2)
		return 1;

	switch (mode) {
	case BSS_CMP_HIDE_ZLEN:
		/*
		 * In ZLEN mode we assume the BSS entry we're
		 * looking for has a zero-length SSID. So if
		 * the one we're looking at right now has that,
		 * return 0. Otherwise, return the difference
		 * in length, but since we're looking for the
		 * 0-length it's really equivalent to returning
		 * the length of the one we're looking at.
		 *
		 * No content comparison is needed as we assume
		 * the content length is zero.
		 */
		return ie2[1];
	case BSS_CMP_REGULAR:
	default:
		/* sort by length first, then by contents */
		if (ie1[1] != ie2[1])
			return ie2[1] - ie1[1];
		return memcmp(ie1 + 2, ie2 + 2, ie1[1]);
	case BSS_CMP_HIDE_NUL:
		if (ie1[1] != ie2[1])
			return ie2[1] - ie1[1];
		/* this is equivalent to memcmp(zeroes, ie2 + 2, len) */
		for (i = 0; i < ie2[1]; i++)
			if (ie2[i + 2])
				return -1;
		return 0;
	}
}

/* Returned bss is reference counted and must be cleaned up appropriately. */
struct cfg80211_bss *cfg80211_get_bss(struct wiphy *wiphy,
				      struct ieee80211_channel *channel,
				      const u8 *bssid,
				      const u8 *ssid, size_t ssid_len,
				      u16 capa_mask, u16 capa_val)
{
	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
	struct cfg80211_internal_bss *bss, *res = NULL;
	unsigned long now = jiffies;

	trace_cfg80211_get_bss(wiphy, channel, bssid, ssid, ssid_len, capa_mask,
			       capa_val);

	spin_lock_bh(&rdev->bss_lock);

	list_for_each_entry(bss, &rdev->bss_list, list) {
		if ((bss->pub.capability & capa_mask) != capa_val)
			continue;
		if (channel && bss->pub.channel != channel)
			continue;
		if (!is_valid_ether_addr(bss->pub.bssid))
			continue;
		/* Don't get expired BSS structs */
		if (time_after(now, bss->ts + IEEE80211_SCAN_RESULT_EXPIRE) &&
		    !atomic_read(&bss->hold))
			continue;
		if (is_bss(&bss->pub, bssid, ssid, ssid_len)) {
			res = bss;
			bss_ref_get(rdev, res);
			break;
		}
	}

	spin_unlock_bh(&rdev->bss_lock);
	if (!res)
		return NULL;
	trace_cfg80211_return_bss(&res->pub);
	return &res->pub;
}
EXPORT_SYMBOL(cfg80211_get_bss);

static void rb_insert_bss(struct cfg80211_registered_device *rdev,
			  struct cfg80211_internal_bss *bss)
{
	struct rb_node **p = &rdev->bss_tree.rb_node;
	struct rb_node *parent = NULL;
	struct cfg80211_internal_bss *tbss;
	int cmp;

	while (*p) {
		parent = *p;
		tbss = rb_entry(parent, struct cfg80211_internal_bss, rbn);

		cmp = cmp_bss(&bss->pub, &tbss->pub, BSS_CMP_REGULAR);

		if (WARN_ON(!cmp)) {
			/* will sort of leak this BSS */
			return;
		}

		if (cmp < 0)
			p = &(*p)->rb_left;
		else
			p = &(*p)->rb_right;
	}

	rb_link_node(&bss->rbn, parent, p);
	rb_insert_color(&bss->rbn, &rdev->bss_tree);
}

static struct cfg80211_internal_bss *
rb_find_bss(struct cfg80211_registered_device *rdev,
	    struct cfg80211_internal_bss *res,
	    enum bss_compare_mode mode)
{
	struct rb_node *n = rdev->bss_tree.rb_node;
	struct cfg80211_internal_bss *bss;
	int r;

	while (n) {
		bss = rb_entry(n, struct cfg80211_internal_bss, rbn);
		r = cmp_bss(&res->pub, &bss->pub, mode);

		if (r == 0)
			return bss;
		else if (r < 0)
			n = n->rb_left;
		else
			n = n->rb_right;
	}

	return NULL;
}

static bool cfg80211_combine_bsses(struct cfg80211_registered_device *rdev,
				   struct cfg80211_internal_bss *new)
{
	const struct cfg80211_bss_ies *ies;
	struct cfg80211_internal_bss *bss;
	const u8 *ie;
	int i, ssidlen;
	u8 fold = 0;

	ies = rcu_access_pointer(new->pub.beacon_ies);
	if (WARN_ON(!ies))
		return false;

	ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
	if (!ie) {
		/* nothing to do */
		return true;
	}

	ssidlen = ie[1];
	for (i = 0; i < ssidlen; i++)
		fold |= ie[2 + i];

	if (fold) {
		/* not a hidden SSID */
		return true;
	}

	/* This is the bad part ... */

	list_for_each_entry(bss, &rdev->bss_list, list) {
		if (!ether_addr_equal(bss->pub.bssid, new->pub.bssid))
			continue;
		if (bss->pub.channel != new->pub.channel)
			continue;
		if (bss->pub.scan_width != new->pub.scan_width)
			continue;
		if (rcu_access_pointer(bss->pub.beacon_ies))
			continue;
		ies = rcu_access_pointer(bss->pub.ies);
		if (!ies)
			continue;
		ie = cfg80211_find_ie(WLAN_EID_SSID, ies->data, ies->len);
		if (!ie)
			continue;
		if (ssidlen && ie[1] != ssidlen)
			continue;
		if (WARN_ON_ONCE(bss->pub.hidden_beacon_bss))
			continue;
		if (WARN_ON_ONCE(!list_empty(&bss->hidden_list)))
			list_del(&bss->hidden_list);
		/* combine them */
		list_add(&bss->hidden_list, &new->hidden_list);
		bss->pub.hidden_beacon_bss = &new->pub;
		new->refcount += bss->refcount;
		rcu_assign_pointer(bss->pub.beacon_ies,
				   new->pub.beacon_ies);
	}

	return true;
}

/* Returned bss is reference counted and must be cleaned up appropriately. */
static struct cfg80211_internal_bss *
cfg80211_bss_update(struct cfg80211_registered_device *rdev,
		    struct cfg80211_internal_bss *tmp,
		    bool signal_valid)
{
	struct cfg80211_internal_bss *found = NULL;

	if (WARN_ON(!tmp->pub.channel))
		return NULL;

	tmp->ts = jiffies;

	spin_lock_bh(&rdev->bss_lock);

	if (WARN_ON(!rcu_access_pointer(tmp->pub.ies))) {
		spin_unlock_bh(&rdev->bss_lock);
		return NULL;
	}

	found = rb_find_bss(rdev, tmp, BSS_CMP_REGULAR);

	if (found) {
		/* Update IEs */
		if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
			const struct cfg80211_bss_ies *old;

			old = rcu_access_pointer(found->pub.proberesp_ies);

			rcu_assign_pointer(found->pub.proberesp_ies,
					   tmp->pub.proberesp_ies);
			/* Override possible earlier Beacon frame IEs */
			rcu_assign_pointer(found->pub.ies,
					   tmp->pub.proberesp_ies);
			if (old)
				kfree_rcu((struct cfg80211_bss_ies *)old,
					  rcu_head);
		} else if (rcu_access_pointer(tmp->pub.beacon_ies)) {
			const struct cfg80211_bss_ies *old;
			struct cfg80211_internal_bss *bss;

			if (found->pub.hidden_beacon_bss &&
			    !list_empty(&found->hidden_list)) {
				const struct cfg80211_bss_ies *f;

				/*
				 * The found BSS struct is one of the probe
				 * response members of a group, but we're
				 * receiving a beacon (beacon_ies in the tmp
				 * bss is used). This can only mean that the
				 * AP changed its beacon from not having an
				 * SSID to showing it, which is confusing so
				 * drop this information.
				 */

				f = rcu_access_pointer(tmp->pub.beacon_ies);
				kfree_rcu((struct cfg80211_bss_ies *)f,
					  rcu_head);
				goto drop;
			}

			old = rcu_access_pointer(found->pub.beacon_ies);

			rcu_assign_pointer(found->pub.beacon_ies,
					   tmp->pub.beacon_ies);

			/* Override IEs if they were from a beacon before */
			if (old == rcu_access_pointer(found->pub.ies))
				rcu_assign_pointer(found->pub.ies,
						   tmp->pub.beacon_ies);

			/* Assign beacon IEs to all sub entries */
			list_for_each_entry(bss, &found->hidden_list,
					    hidden_list) {
				const struct cfg80211_bss_ies *ies;

				ies = rcu_access_pointer(bss->pub.beacon_ies);
				WARN_ON(ies != old);

				rcu_assign_pointer(bss->pub.beacon_ies,
						   tmp->pub.beacon_ies);
			}

			if (old)
				kfree_rcu((struct cfg80211_bss_ies *)old,
					  rcu_head);
		}

		found->pub.beacon_interval = tmp->pub.beacon_interval;
		/*
		 * don't update the signal if beacon was heard on
		 * adjacent channel.
		 */
		if (signal_valid)
			found->pub.signal = tmp->pub.signal;
		found->pub.capability = tmp->pub.capability;
		found->ts = tmp->ts;
	} else {
		struct cfg80211_internal_bss *new;
		struct cfg80211_internal_bss *hidden;
		struct cfg80211_bss_ies *ies;

		/*
		 * create a copy -- the "res" variable that is passed in
		 * is allocated on the stack since it's not needed in the
		 * more common case of an update
		 */
		new = kzalloc(sizeof(*new) + rdev->wiphy.bss_priv_size,
			      GFP_ATOMIC);
		if (!new) {
			ies = (void *)rcu_dereference(tmp->pub.beacon_ies);
			if (ies)
				kfree_rcu(ies, rcu_head);
			ies = (void *)rcu_dereference(tmp->pub.proberesp_ies);
			if (ies)
				kfree_rcu(ies, rcu_head);
			goto drop;
		}
		memcpy(new, tmp, sizeof(*new));
		new->refcount = 1;
		INIT_LIST_HEAD(&new->hidden_list);

		if (rcu_access_pointer(tmp->pub.proberesp_ies)) {
			hidden = rb_find_bss(rdev, tmp, BSS_CMP_HIDE_ZLEN);
			if (!hidden)
				hidden = rb_find_bss(rdev, tmp,
						     BSS_CMP_HIDE_NUL);
			if (hidden) {
				new->pub.hidden_beacon_bss = &hidden->pub;
				list_add(&new->hidden_list,
					 &hidden->hidden_list);
				hidden->refcount++;
				rcu_assign_pointer(new->pub.beacon_ies,
						   hidden->pub.beacon_ies);
			}
		} else {
			/*
			 * Ok so we found a beacon, and don't have an entry. If
			 * it's a beacon with hidden SSID, we might be in for an
			 * expensive search for any probe responses that should
			 * be grouped with this beacon for updates ...
			 */
			if (!cfg80211_combine_bsses(rdev, new)) {
				kfree(new);
				goto drop;
			}
		}

		list_add_tail(&new->list, &rdev->bss_list);
		rb_insert_bss(rdev, new);
		found = new;
	}

	rdev->bss_generation++;
	bss_ref_get(rdev, found);
	spin_unlock_bh(&rdev->bss_lock);

	return found;


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