cfg80211: restructure AP/GO mode API

The AP/GO mode API isn't very clearly defined, it
has "set beacon" and "new beacon" etc.

Modify the API to the following:
 * start AP -- all settings
 * change beacon -- new beacon data
 * stop AP -- stop AP mode operation

This also reflects in the nl80211 API, rename
the commands there correspondingly (but keep
the old names for compatibility.)

Overall, this makes it much clearer what's going
on in the API.

Kalle developed the ath6kl changes, I created
the rest of the patch.
Signed-off-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

drivers/net/wireless/ath/ath6kl/cfg80211.c

@@ -2269,25 +2269,11 @@ static int ath6kl_set_ap_probe_resp_ies(struct ath6kl_vif *vif,
 	return ret;
 }
 
-static int ath6kl_ap_beacon(struct wiphy *wiphy, struct net_device *dev,
-			    struct beacon_parameters *info, bool add)
+static int ath6kl_set_ies(struct ath6kl_vif *vif,
+			  struct cfg80211_beacon_data *info)
 {
-	struct ath6kl *ar = ath6kl_priv(dev);
-	struct ath6kl_vif *vif = netdev_priv(dev);
-	struct ieee80211_mgmt *mgmt;
-	u8 *ies;
-	int ies_len;
-	struct wmi_connect_cmd p;
+	struct ath6kl *ar = vif->ar;
 	int res;
-	int i, ret;
-
-	ath6kl_dbg(ATH6KL_DBG_WLAN_CFG, "%s: add=%d\n", __func__, add);
-
-	if (!ath6kl_cfg80211_ready(vif))
-		return -EIO;
-
-	if (vif->next_mode != AP_NETWORK)
-		return -EOPNOTSUPP;
 
 	if (info->beacon_ies) {
 		res = ath6kl_wmi_set_appie_cmd(ar->wmi, vif->fw_vif_idx,
@@ -2297,12 +2283,14 @@ static int ath6kl_ap_beacon(struct wiphy *wiphy, struct net_device *dev,
 		if (res)
 			return res;
 	}
+
 	if (info->proberesp_ies) {
 		res = ath6kl_set_ap_probe_resp_ies(vif, info->proberesp_ies,
 						   info->proberesp_ies_len);
 		if (res)
 			return res;
 	}
+
 	if (info->assocresp_ies) {
 		res = ath6kl_wmi_set_appie_cmd(ar->wmi, vif->fw_vif_idx,
 					       WMI_FRAME_ASSOC_RESP,
@@ -2312,8 +2300,30 @@ static int ath6kl_ap_beacon(struct wiphy *wiphy, struct net_device *dev,
 			return res;
 	}
 
-	if (!add)
-		return 0;
+	return 0;
+}
+
+static int ath6kl_start_ap(struct wiphy *wiphy, struct net_device *dev,
+			   struct cfg80211_ap_settings *info)
+{
+	struct ath6kl *ar = ath6kl_priv(dev);
+	struct ath6kl_vif *vif = netdev_priv(dev);
+	struct ieee80211_mgmt *mgmt;
+	u8 *ies;
+	int ies_len;
+	struct wmi_connect_cmd p;
+	int res;
+	int i, ret;
+
+	ath6kl_dbg(ATH6KL_DBG_WLAN_CFG, "%s:\n", __func__);
+
+	if (!ath6kl_cfg80211_ready(vif))
+		return -EIO;
+
+	if (vif->next_mode != AP_NETWORK)
+		return -EOPNOTSUPP;
+
+	res = ath6kl_set_ies(vif, &info->beacon);
 
 	ar->ap_mode_bkey.valid = false;
 
@@ -2322,13 +2332,13 @@ static int ath6kl_ap_beacon(struct wiphy *wiphy, struct net_device *dev,
 	 * info->dtim_period
 	 */
 
-	if (info->head == NULL)
+	if (info->beacon.head == NULL)
 		return -EINVAL;
-	mgmt = (struct ieee80211_mgmt *) info->head;
+	mgmt = (struct ieee80211_mgmt *) info->beacon.head;
 	ies = mgmt->u.beacon.variable;
-	if (ies > info->head + info->head_len)
+	if (ies > info->beacon.head + info->beacon.head_len)
 		return -EINVAL;
-	ies_len = info->head + info->head_len - ies;
+	ies_len = info->beacon.head + info->beacon.head_len - ies;
 
 	if (info->ssid == NULL)
 		return -EINVAL;
@@ -2436,19 +2446,21 @@ static int ath6kl_ap_beacon(struct wiphy *wiphy, struct net_device *dev,
 	return 0;
 }
 
-static int ath6kl_add_beacon(struct wiphy *wiphy, struct net_device *dev,
-			     struct beacon_parameters *info)
+static int ath6kl_change_beacon(struct wiphy *wiphy, struct net_device *dev,
+				struct cfg80211_beacon_data *beacon)
 {
-	return ath6kl_ap_beacon(wiphy, dev, info, true);
-}
+	struct ath6kl_vif *vif = netdev_priv(dev);
 
-static int ath6kl_set_beacon(struct wiphy *wiphy, struct net_device *dev,
-			     struct beacon_parameters *info)
-{
-	return ath6kl_ap_beacon(wiphy, dev, info, false);
+	if (!ath6kl_cfg80211_ready(vif))
+		return -EIO;
+
+	if (vif->next_mode != AP_NETWORK)
+		return -EOPNOTSUPP;
+
+	return ath6kl_set_ies(vif, beacon);
 }
 
-static int ath6kl_del_beacon(struct wiphy *wiphy, struct net_device *dev)
+static int ath6kl_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 {
 	struct ath6kl *ar = ath6kl_priv(dev);
 	struct ath6kl_vif *vif = netdev_priv(dev);
@@ -2783,9 +2795,9 @@ static struct cfg80211_ops ath6kl_cfg80211_ops = {
 	.resume = __ath6kl_cfg80211_resume,
 #endif
 	.set_channel = ath6kl_set_channel,
-	.add_beacon = ath6kl_add_beacon,
-	.set_beacon = ath6kl_set_beacon,
-	.del_beacon = ath6kl_del_beacon,
+	.start_ap = ath6kl_start_ap,
+	.change_beacon = ath6kl_change_beacon,
+	.stop_ap = ath6kl_stop_ap,
 	.del_station = ath6kl_del_station,
 	.change_station = ath6kl_change_station,
 	.remain_on_channel = ath6kl_remain_on_channel,

include/linux/nl80211.h

@@ -156,21 +156,23 @@
  * @NL80211_CMD_DEL_KEY: delete a key identified by %NL80211_ATTR_KEY_IDX
  *	or %NL80211_ATTR_MAC.
  *
- * @NL80211_CMD_GET_BEACON: retrieve beacon information (returned in a
- *	%NL80222_CMD_NEW_BEACON message)
- * @NL80211_CMD_SET_BEACON: set the beacon on an access point interface
- *	using the %NL80211_ATTR_BEACON_INTERVAL, %NL80211_ATTR_DTIM_PERIOD,
- *	%NL80211_ATTR_BEACON_HEAD and %NL80211_ATTR_BEACON_TAIL attributes.
- *	Following attributes are provided for drivers that generate full Beacon
- *	and Probe Response frames internally: %NL80211_ATTR_SSID,
+ * @NL80211_CMD_GET_BEACON: (not used)
+ * @NL80211_CMD_SET_BEACON: change the beacon on an access point interface
+ *	using the %NL80211_ATTR_BEACON_HEAD and %NL80211_ATTR_BEACON_TAIL
+ *	attributes. For drivers that generate the beacon and probe responses
+ *	internally, the following attributes must be provided: %NL80211_ATTR_IE,
+ *	%NL80211_ATTR_IE_PROBE_RESP and %NL80211_ATTR_IE_ASSOC_RESP.
+ * @NL80211_CMD_START_AP: Start AP operation on an AP interface, parameters
+ *	are like for %NL80211_CMD_SET_BEACON, and additionally parameters that
+ *	do not change are used, these include %NL80211_ATTR_BEACON_INTERVAL,
+ *	%NL80211_ATTR_DTIM_PERIOD, %NL80211_ATTR_SSID,
  *	%NL80211_ATTR_HIDDEN_SSID, %NL80211_ATTR_CIPHERS_PAIRWISE,
  *	%NL80211_ATTR_CIPHER_GROUP, %NL80211_ATTR_WPA_VERSIONS,
- *	%NL80211_ATTR_AKM_SUITES, %NL80211_ATTR_PRIVACY,
- *	%NL80211_ATTR_AUTH_TYPE, %NL80211_ATTR_IE, %NL80211_ATTR_IE_PROBE_RESP,
- *	%NL80211_ATTR_IE_ASSOC_RESP.
- * @NL80211_CMD_NEW_BEACON: add a new beacon to an access point interface,
- *	parameters are like for %NL80211_CMD_SET_BEACON.
- * @NL80211_CMD_DEL_BEACON: remove the beacon, stop sending it
+ *	%NL80211_ATTR_AKM_SUITES, %NL80211_ATTR_PRIVACY and
+ *	%NL80211_ATTR_AUTH_TYPE.
+ * @NL80211_CMD_NEW_BEACON: old alias for %NL80211_CMD_START_AP
+ * @NL80211_CMD_STOP_AP: Stop AP operation on the given interface
+ * @NL80211_CMD_DEL_BEACON: old alias for %NL80211_CMD_STOP_AP
  *
  * @NL80211_CMD_GET_STATION: Get station attributes for station identified by
  *	%NL80211_ATTR_MAC on the interface identified by %NL80211_ATTR_IFINDEX.
@@ -565,8 +567,10 @@ enum nl80211_commands {
 
 	NL80211_CMD_GET_BEACON,
 	NL80211_CMD_SET_BEACON,
-	NL80211_CMD_NEW_BEACON,
-	NL80211_CMD_DEL_BEACON,
+	NL80211_CMD_START_AP,
+	NL80211_CMD_NEW_BEACON = NL80211_CMD_START_AP,
+	NL80211_CMD_STOP_AP,
+	NL80211_CMD_DEL_BEACON = NL80211_CMD_STOP_AP,
 
 	NL80211_CMD_GET_STATION,
 	NL80211_CMD_SET_STATION,

include/net/cfg80211.h

@@ -366,25 +366,13 @@ struct cfg80211_crypto_settings {
 };
 
 /**
- * struct beacon_parameters - beacon parameters
- *
- * Used to configure the beacon for an interface.
- *
+ * struct cfg80211_beacon_data - beacon data
  * @head: head portion of beacon (before TIM IE)
  *     or %NULL if not changed
  * @tail: tail portion of beacon (after TIM IE)
  *     or %NULL if not changed
- * @interval: beacon interval or zero if not changed
- * @dtim_period: DTIM period or zero if not changed
  * @head_len: length of @head
  * @tail_len: length of @tail
- * @ssid: SSID to be used in the BSS (note: may be %NULL if not provided from
- *	user space)
- * @ssid_len: length of @ssid
- * @hidden_ssid: whether to hide the SSID in Beacon/Probe Response frames
- * @crypto: crypto settings
- * @privacy: the BSS uses privacy
- * @auth_type: Authentication type (algorithm)
  * @beacon_ies: extra information element(s) to add into Beacon frames or %NULL
  * @beacon_ies_len: length of beacon_ies in octets
  * @proberesp_ies: extra information element(s) to add into Probe Response
@@ -396,24 +384,46 @@ struct cfg80211_crypto_settings {
  * @probe_resp_len: length of probe response template (@probe_resp)
  * @probe_resp: probe response template (AP mode only)
  */
-struct beacon_parameters {
-	u8 *head, *tail;
-	int interval, dtim_period;
-	int head_len, tail_len;
+struct cfg80211_beacon_data {
+	const u8 *head, *tail;
+	const u8 *beacon_ies;
+	const u8 *proberesp_ies;
+	const u8 *assocresp_ies;
+	const u8 *probe_resp;
+
+	size_t head_len, tail_len;
+	size_t beacon_ies_len;
+	size_t proberesp_ies_len;
+	size_t assocresp_ies_len;
+	size_t probe_resp_len;
+};
+
+/**
+ * struct cfg80211_ap_settings - AP configuration
+ *
+ * Used to configure an AP interface.
+ *
+ * @beacon: beacon data
+ * @beacon_interval: beacon interval
+ * @dtim_period: DTIM period
+ * @ssid: SSID to be used in the BSS (note: may be %NULL if not provided from
+ *	user space)
+ * @ssid_len: length of @ssid
+ * @hidden_ssid: whether to hide the SSID in Beacon/Probe Response frames
+ * @crypto: crypto settings
+ * @privacy: the BSS uses privacy
+ * @auth_type: Authentication type (algorithm)
+ */
+struct cfg80211_ap_settings {
+	struct cfg80211_beacon_data beacon;
+
+	int beacon_interval, dtim_period;
 	const u8 *ssid;
 	size_t ssid_len;
 	enum nl80211_hidden_ssid hidden_ssid;
 	struct cfg80211_crypto_settings crypto;
 	bool privacy;
 	enum nl80211_auth_type auth_type;
-	const u8 *beacon_ies;
-	size_t beacon_ies_len;
-	const u8 *proberesp_ies;
-	size_t proberesp_ies_len;
-	const u8 *assocresp_ies;
-	size_t assocresp_ies_len;
-	int probe_resp_len;
-	u8 *probe_resp;
 };
 
 /**
@@ -1518,11 +1528,11 @@ struct cfg80211_ops {
 					struct net_device *netdev,
 					u8 key_index);
 
-	int	(*add_beacon)(struct wiphy *wiphy, struct net_device *dev,
-			      struct beacon_parameters *info);
-	int	(*set_beacon)(struct wiphy *wiphy, struct net_device *dev,
-			      struct beacon_parameters *info);
-	int	(*del_beacon)(struct wiphy *wiphy, struct net_device *dev);
+	int	(*start_ap)(struct wiphy *wiphy, struct net_device *dev,
+			    struct cfg80211_ap_settings *settings);
+	int	(*change_beacon)(struct wiphy *wiphy, struct net_device *dev,
+				 struct cfg80211_beacon_data *info);
+	int	(*stop_ap)(struct wiphy *wiphy, struct net_device *dev);
 
 
 	int	(*add_station)(struct wiphy *wiphy, struct net_device *dev,

net/mac80211/cfg.c

@@ -489,27 +489,13 @@ static int ieee80211_get_station(struct wiphy *wiphy, struct net_device *dev,
 	return ret;
 }
 
-static void ieee80211_config_ap_ssid(struct ieee80211_sub_if_data *sdata,
-				     struct beacon_parameters *params)
-{
-	struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf;
-
-	bss_conf->ssid_len = params->ssid_len;
-
-	if (params->ssid_len)
-		memcpy(bss_conf->ssid, params->ssid, params->ssid_len);
-
-	bss_conf->hidden_ssid =
-		(params->hidden_ssid != NL80211_HIDDEN_SSID_NOT_IN_USE);
-}
-
 static int ieee80211_set_probe_resp(struct ieee80211_sub_if_data *sdata,
-				    u8 *resp, size_t resp_len)
+				    const u8 *resp, size_t resp_len)
 {
 	struct sk_buff *new, *old;
 
 	if (!resp || !resp_len)
-		return -EINVAL;
+		return 1;
 
 	old = rtnl_dereference(sdata->u.ap.probe_resp);
 
@@ -520,50 +506,28 @@ static int ieee80211_set_probe_resp(struct ieee80211_sub_if_data *sdata,
 	memcpy(skb_put(new, resp_len), resp, resp_len);
 
 	rcu_assign_pointer(sdata->u.ap.probe_resp, new);
-	synchronize_rcu();
-
-	if (old)
+	if (old) {
+		/* TODO: use call_rcu() */
+		synchronize_rcu();
 		dev_kfree_skb(old);
+	}
 
 	return 0;
 }
 
-/*
- * This handles both adding a beacon and setting new beacon info
- */
-static int ieee80211_config_beacon(struct ieee80211_sub_if_data *sdata,
-				   struct beacon_parameters *params)
+static int ieee80211_assign_beacon(struct ieee80211_sub_if_data *sdata,
+				   struct cfg80211_beacon_data *params)
 {
 	struct beacon_data *new, *old;
 	int new_head_len, new_tail_len;
-	int size;
-	int err = -EINVAL;
-	u32 changed = 0;
+	int size, err;
+	u32 changed = BSS_CHANGED_BEACON;
 
 	old = rtnl_dereference(sdata->u.ap.beacon);
 
-	/* head must not be zero-length */
-	if (params->head && !params->head_len)
-		return -EINVAL;
-
-	/*
-	 * This is a kludge. beacon interval should really be part
-	 * of the beacon information.
-	 */
-	if (params->interval &&
-	    (sdata->vif.bss_conf.beacon_int != params->interval)) {
-		sdata->vif.bss_conf.beacon_int = params->interval;
-		ieee80211_bss_info_change_notify(sdata,
-						 BSS_CHANGED_BEACON_INT);
-	}
-
 	/* Need to have a beacon head if we don't have one yet */
 	if (!params->head && !old)
-		return err;
-
-	/* sorry, no way to start beaconing without dtim period */
-	if (!params->dtim_period && !old)
-		return err;
+		return -EINVAL;
 
 	/* new or old head? */
 	if (params->head)
@@ -586,12 +550,6 @@ static int ieee80211_config_beacon(struct ieee80211_sub_if_data *sdata,
 
 	/* start filling the new info now */
 
-	/* new or old dtim period? */
-	if (params->dtim_period)
-		new->dtim_period = params->dtim_period;
-	else
-		new->dtim_period = old->dtim_period;
-
 	/*
 	 * pointers go into the block we allocated,
 	 * memory is | beacon_data | head | tail |
@@ -614,46 +572,37 @@ static int ieee80211_config_beacon(struct ieee80211_sub_if_data *sdata,
 		if (old)
 			memcpy(new->tail, old->tail, new_tail_len);
 
-	sdata->vif.bss_conf.dtim_period = new->dtim_period;
-
-	rcu_assign_pointer(sdata->u.ap.beacon, new);
-
-	synchronize_rcu();
-
-	kfree(old);
-
 	err = ieee80211_set_probe_resp(sdata, params->probe_resp,
 				       params->probe_resp_len);
-	if (!err)
+	if (err < 0)
+		return err;
+	if (err == 0)
 		changed |= BSS_CHANGED_AP_PROBE_RESP;
 
-	ieee80211_config_ap_ssid(sdata, params);
-	changed |= BSS_CHANGED_BEACON_ENABLED |
-		   BSS_CHANGED_BEACON |
-		   BSS_CHANGED_SSID;
+	rcu_assign_pointer(sdata->u.ap.beacon, new);
+
+	if (old)
+		kfree_rcu(old, rcu_head);
 
-	ieee80211_bss_info_change_notify(sdata, changed);
-	return 0;
+	return changed;
 }
 
-static int ieee80211_add_beacon(struct wiphy *wiphy, struct net_device *dev,
-				struct beacon_parameters *params)
+static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
+			      struct cfg80211_ap_settings *params)
 {
-	struct ieee80211_sub_if_data *sdata;
+	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct beacon_data *old;
 	struct ieee80211_sub_if_data *vlan;
-	int ret;
-
-	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+	u32 changed = BSS_CHANGED_BEACON_INT |
+		      BSS_CHANGED_BEACON_ENABLED |
+		      BSS_CHANGED_BEACON |
+		      BSS_CHANGED_SSID;
+	int err;
 
 	old = rtnl_dereference(sdata->u.ap.beacon);
 	if (old)
 		return -EALREADY;
 
-	ret = ieee80211_config_beacon(sdata, params);
-	if (ret)
-		return ret;
-
 	/*
 	 * Apply control port protocol, this allows us to
 	 * not encrypt dynamic WEP control frames.
@@ -667,14 +616,32 @@ static int ieee80211_add_beacon(struct wiphy *wiphy, struct net_device *dev,
 			params->crypto.control_port_no_encrypt;
 	}
 
+	sdata->vif.bss_conf.beacon_int = params->beacon_interval;
+	sdata->vif.bss_conf.dtim_period = params->dtim_period;
+
+	sdata->vif.bss_conf.ssid_len = params->ssid_len;
+	if (params->ssid_len)
+		memcpy(sdata->vif.bss_conf.ssid, params->ssid,
+		       params->ssid_len);
+	sdata->vif.bss_conf.hidden_ssid =
+		(params->hidden_ssid != NL80211_HIDDEN_SSID_NOT_IN_USE);
+
+	err = ieee80211_assign_beacon(sdata, &params->beacon);
+	if (err < 0)
+		return err;
+	changed |= err;
+
+	ieee80211_bss_info_change_notify(sdata, changed);
+
 	return 0;
 }
 
-static int ieee80211_set_beacon(struct wiphy *wiphy, struct net_device *dev,
-				struct beacon_parameters *params)
+static int ieee80211_change_beacon(struct wiphy *wiphy, struct net_device *dev,
+				   struct cfg80211_beacon_data *params)
 {
 	struct ieee80211_sub_if_data *sdata;
 	struct beacon_data *old;
+	int err;
 
 	sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 
@@ -682,10 +649,14 @@ static int ieee80211_set_beacon(struct wiphy *wiphy, struct net_device *dev,
 	if (!old)
 		return -ENOENT;
 
-	return ieee80211_config_beacon(sdata, params);
+	err = ieee80211_assign_beacon(sdata, params);
+	if (err < 0)
+		return err;
+	ieee80211_bss_info_change_notify(sdata, err);
+	return 0;
 }
 
-static int ieee80211_del_beacon(struct wiphy *wiphy, struct net_device *dev)
+static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
 {
 	struct ieee80211_sub_if_data *sdata;
 	struct beacon_data *old;
@@ -697,10 +668,11 @@ static int ieee80211_del_beacon(struct wiphy *wiphy, struct net_device *dev)
 		return -ENOENT;
 
 	RCU_INIT_POINTER(sdata->u.ap.beacon, NULL);
-	synchronize_rcu();
-	kfree(old);
+
+	kfree_rcu(old, rcu_head);
 
 	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
+
 	return 0;
 }
 
@@ -2699,9 +2671,9 @@ struct cfg80211_ops mac80211_config_ops = {
 	.get_key = ieee80211_get_key,
 	.set_default_key = ieee80211_config_default_key,
 	.set_default_mgmt_key = ieee80211_config_default_mgmt_key,
-	.add_beacon = ieee80211_add_beacon,
-	.set_beacon = ieee80211_set_beacon,
-	.del_beacon = ieee80211_del_beacon,
+	.start_ap = ieee80211_start_ap,
+	.change_beacon = ieee80211_change_beacon,
+	.stop_ap = ieee80211_stop_ap,
 	.add_station = ieee80211_add_station,
 	.del_station = ieee80211_del_station,
 	.change_station = ieee80211_change_station,

net/mac80211/ieee80211_i.h

@@ -228,7 +228,7 @@ struct ieee80211_rx_data {
 struct beacon_data {
 	u8 *head, *tail;
 	int head_len, tail_len;
-	int dtim_period;
+	struct rcu_head rcu_head;
 };
 
 struct ieee80211_if_ap {

net/mac80211/tx.c

@@ -2206,7 +2206,8 @@ void ieee80211_tx_pending(unsigned long data)
 
 /* functions for drivers to get certain frames */
 
-static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
+static void ieee80211_beacon_add_tim(struct ieee80211_sub_if_data *sdata,
+				     struct ieee80211_if_ap *bss,
 				     struct sk_buff *skb,
 				     struct beacon_data *beacon)
 {
@@ -2223,7 +2224,7 @@ static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
 					  IEEE80211_MAX_AID+1);
 
 	if (bss->dtim_count == 0)
-		bss->dtim_count = beacon->dtim_period - 1;
+		bss->dtim_count = sdata->vif.bss_conf.dtim_period - 1;
 	else
 		bss->dtim_count--;
 
@@ -2231,7 +2232,7 @@ static void ieee80211_beacon_add_tim(struct ieee80211_if_ap *bss,
 	*pos++ = WLAN_EID_TIM;
 	*pos++ = 4;
 	*pos++ = bss->dtim_count;
-	*pos++ = beacon->dtim_period;
+	*pos++ = sdata->vif.bss_conf.dtim_period;
 
 	if (bss->dtim_count == 0 && !skb_queue_empty(&bss->ps_bc_buf))
 		aid0 = 1;
@@ -2324,12 +2325,14 @@ struct sk_buff *ieee80211_beacon_get_tim(struct ieee80211_hw *hw,
 			 * of the tim bitmap in mac80211 and the driver.
 			 */
 			if (local->tim_in_locked_section) {
-				ieee80211_beacon_add_tim(ap, skb, beacon);
+				ieee80211_beacon_add_tim(sdata, ap, skb,
+							 beacon);
 			} else {
 				unsigned long flags;
 
 				spin_lock_irqsave(&local->tim_lock, flags);
-				ieee80211_beacon_add_tim(ap, skb, beacon);
+				ieee80211_beacon_add_tim(sdata, ap, skb,
+							 beacon);
 				spin_unlock_irqrestore(&local->tim_lock, flags);
 			}