mac80211: revamp beacon configuration

This patch changes mac80211's beacon configuration handling
to never pass skbs to the driver directly but rather always
require the driver to use ieee80211_beacon_get(). Additionally,
it introduces "change flags" on the config_interface() call
to enable drivers to figure out what is changing. Finally, it
removes the beacon_update() driver callback in favour of
having IBSS beacon delivered by ieee80211_beacon_get() as well.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

6 files changed, 95 insertions, 121 deletions

diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index ea03010..8e7ba0e 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -469,7 +469,7 @@ static int ieee80211_config_beacon(struct ieee80211_sub_if_data *sdata,
 
 	kfree(old);
 
-	return ieee80211_if_config_beacon(sdata->dev);
+	return ieee80211_if_config(sdata, IEEE80211_IFCC_BEACON);
 }
 
 static int ieee80211_add_beacon(struct wiphy *wiphy, struct net_device *dev,
@@ -523,7 +523,7 @@ static int ieee80211_del_beacon(struct wiphy *wiphy, struct net_device *dev)
 	synchronize_rcu();
 	kfree(old);
 
-	return ieee80211_if_config_beacon(dev);
+	return ieee80211_if_config(sdata, IEEE80211_IFCC_BEACON);
 }
 
 /* Layer 2 Update frame (802.2 Type 1 LLC XID Update response) */
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 2146c0c..934c3ef 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -854,8 +854,7 @@ static inline int ieee80211_bssid_match(const u8 *raddr, const u8 *addr)
 
 /* ieee80211.c */
 int ieee80211_hw_config(struct ieee80211_local *local);
-int ieee80211_if_config(struct net_device *dev);
-int ieee80211_if_config_beacon(struct net_device *dev);
+int ieee80211_if_config(struct ieee80211_sub_if_data *sdata, u32 changed);
 void ieee80211_tx_set_protected(struct ieee80211_tx_data *tx);
 u32 ieee80211_handle_ht(struct ieee80211_local *local, int enable_ht,
 			struct ieee80211_ht_info *req_ht_cap,
diff --git a/net/mac80211/main.c b/net/mac80211/main.c
index 0759ab2c..36859e7 100644
--- a/net/mac80211/main.c
+++ b/net/mac80211/main.c
@@ -307,7 +307,8 @@ static int ieee80211_open(struct net_device *dev)
 		if (res)
 			goto err_stop;
 
-		ieee80211_if_config(dev);
+		if (ieee80211_vif_is_mesh(&sdata->vif))
+			ieee80211_start_mesh(sdata->dev);
 		changed |= ieee80211_reset_erp_info(dev);
 		ieee80211_bss_info_change_notify(sdata, changed);
 		ieee80211_enable_keys(sdata);
@@ -985,57 +986,47 @@ void ieee80211_if_setup(struct net_device *dev)
 
 /* everything else */
 
-static int __ieee80211_if_config(struct net_device *dev,
-				 struct sk_buff *beacon)
+int ieee80211_if_config(struct ieee80211_sub_if_data *sdata, u32 changed)
 {
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
+	struct ieee80211_local *local = sdata->local;
 	struct ieee80211_if_conf conf;
 
-	if (!local->ops->config_interface || !netif_running(dev))
+	if (WARN_ON(!netif_running(sdata->dev)))
+		return 0;
+
+	if (!local->ops->config_interface)
 		return 0;
 
 	memset(&conf, 0, sizeof(conf));
-	conf.type = sdata->vif.type;
+	conf.changed = changed;
+
 	if (sdata->vif.type == IEEE80211_IF_TYPE_STA ||
 	    sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
 		conf.bssid = sdata->u.sta.bssid;
 		conf.ssid = sdata->u.sta.ssid;
 		conf.ssid_len = sdata->u.sta.ssid_len;
-	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
-		conf.beacon = beacon;
-		ieee80211_start_mesh(dev);
 	} else if (sdata->vif.type == IEEE80211_IF_TYPE_AP) {
+		conf.bssid = sdata->dev->dev_addr;
 		conf.ssid = sdata->u.ap.ssid;
 		conf.ssid_len = sdata->u.ap.ssid_len;
-		conf.beacon = beacon;
+	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
+		u8 zero[ETH_ALEN] = { 0 };
+		conf.bssid = zero;
+		conf.ssid = zero;
+		conf.ssid_len = 0;
+	} else {
+		WARN_ON(1);
+		return -EINVAL;
 	}
-	return local->ops->config_interface(local_to_hw(local),
-					    &sdata->vif, &conf);
-}
 
-int ieee80211_if_config(struct net_device *dev)
-{
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
-	if (sdata->vif.type == IEEE80211_IF_TYPE_MESH_POINT &&
-	    (local->hw.flags & IEEE80211_HW_HOST_GEN_BEACON_TEMPLATE))
-		return ieee80211_if_config_beacon(dev);
-	return __ieee80211_if_config(dev, NULL);
-}
+	if (WARN_ON(!conf.bssid && (changed & IEEE80211_IFCC_BSSID)))
+		return -EINVAL;
 
-int ieee80211_if_config_beacon(struct net_device *dev)
-{
-	struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
-	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
-	struct sk_buff *skb;
+	if (WARN_ON(!conf.ssid && (changed & IEEE80211_IFCC_SSID)))
+		return -EINVAL;
 
-	if (!(local->hw.flags & IEEE80211_HW_HOST_GEN_BEACON_TEMPLATE))
-		return 0;
-	skb = ieee80211_beacon_get(local_to_hw(local), &sdata->vif);
-	if (!skb)
-		return -ENOMEM;
-	return __ieee80211_if_config(dev, skb);
+	return local->ops->config_interface(local_to_hw(local),
+					    &sdata->vif, &conf);
 }
 
 int ieee80211_hw_config(struct ieee80211_local *local)
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 64d710a..61d7f81 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -2406,8 +2406,6 @@ static int ieee80211_sta_join_ibss(struct net_device *dev,
 	int res, rates, i, j;
 	struct sk_buff *skb;
 	struct ieee80211_mgmt *mgmt;
-	struct ieee80211_tx_info *control;
-	struct rate_selection ratesel;
 	u8 *pos;
 	struct ieee80211_sub_if_data *sdata;
 	struct ieee80211_supported_band *sband;
@@ -2425,7 +2423,7 @@ static int ieee80211_sta_join_ibss(struct net_device *dev,
 		local->ops->reset_tsf(local_to_hw(local));
 	}
 	memcpy(ifsta->bssid, bss->bssid, ETH_ALEN);
-	res = ieee80211_if_config(dev);
+	res = ieee80211_if_config(sdata, IEEE80211_IFCC_BSSID);
 	if (res)
 		return res;
 
@@ -2439,19 +2437,16 @@ static int ieee80211_sta_join_ibss(struct net_device *dev,
 	if (res)
 		return res;
 
-	/* Set beacon template */
+	/* Build IBSS probe response */
 	skb = dev_alloc_skb(local->hw.extra_tx_headroom + 400);
-	do {
-		if (!skb)
-			break;
-
+	if (skb) {
 		skb_reserve(skb, local->hw.extra_tx_headroom);
 
 		mgmt = (struct ieee80211_mgmt *)
 			skb_put(skb, 24 + sizeof(mgmt->u.beacon));
 		memset(mgmt, 0, 24 + sizeof(mgmt->u.beacon));
 		mgmt->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
-						   IEEE80211_STYPE_BEACON);
+						   IEEE80211_STYPE_PROBE_RESP);
 		memset(mgmt->da, 0xff, ETH_ALEN);
 		memcpy(mgmt->sa, dev->dev_addr, ETH_ALEN);
 		memcpy(mgmt->bssid, ifsta->bssid, ETH_ALEN);
@@ -2495,61 +2490,22 @@ static int ieee80211_sta_join_ibss(struct net_device *dev,
 			memcpy(pos, &bss->supp_rates[8], rates);
 		}
 
-		control = IEEE80211_SKB_CB(skb);
-
-		rate_control_get_rate(dev, sband, skb, &ratesel);
-		if (ratesel.rate_idx < 0) {
-			printk(KERN_DEBUG "%s: Failed to determine TX rate "
-			       "for IBSS beacon\n", dev->name);
-			break;
-		}
-		control->control.vif = &sdata->vif;
-		control->tx_rate_idx = ratesel.rate_idx;
-		if (sdata->bss_conf.use_short_preamble &&
-		    sband->bitrates[ratesel.rate_idx].flags & IEEE80211_RATE_SHORT_PREAMBLE)
-			control->flags |= IEEE80211_TX_CTL_SHORT_PREAMBLE;
-		control->antenna_sel_tx = local->hw.conf.antenna_sel_tx;
-		control->flags |= IEEE80211_TX_CTL_NO_ACK;
-		control->flags |= IEEE80211_TX_CTL_DO_NOT_ENCRYPT;
-		control->control.retry_limit = 1;
-
-		ifsta->probe_resp = skb_copy(skb, GFP_ATOMIC);
-		if (ifsta->probe_resp) {
-			mgmt = (struct ieee80211_mgmt *)
-				ifsta->probe_resp->data;
-			mgmt->frame_control =
-				IEEE80211_FC(IEEE80211_FTYPE_MGMT,
-					     IEEE80211_STYPE_PROBE_RESP);
-		} else {
-			printk(KERN_DEBUG "%s: Could not allocate ProbeResp "
-			       "template for IBSS\n", dev->name);
-		}
-
-		if (local->ops->beacon_update &&
-		    local->ops->beacon_update(local_to_hw(local), skb) == 0) {
-			printk(KERN_DEBUG "%s: Configured IBSS beacon "
-			       "template\n", dev->name);
-			skb = NULL;
-		}
-
-		rates = 0;
-		sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
-		for (i = 0; i < bss->supp_rates_len; i++) {
-			int bitrate = (bss->supp_rates[i] & 0x7f) * 5;
-			for (j = 0; j < sband->n_bitrates; j++)
-				if (sband->bitrates[j].bitrate == bitrate)
-					rates |= BIT(j);
-		}
-		ifsta->supp_rates_bits[local->hw.conf.channel->band] = rates;
+		ifsta->probe_resp = skb;
 
-		ieee80211_sta_def_wmm_params(dev, bss, 1);
-	} while (0);
+		ieee80211_if_config(sdata, IEEE80211_IFCC_BEACON);
+	}
 
-	if (skb) {
-		printk(KERN_DEBUG "%s: Failed to configure IBSS beacon "
-		       "template\n", dev->name);
-		dev_kfree_skb(skb);
+	rates = 0;
+	sband = local->hw.wiphy->bands[local->hw.conf.channel->band];
+	for (i = 0; i < bss->supp_rates_len; i++) {
+		int bitrate = (bss->supp_rates[i] & 0x7f) * 5;
+		for (j = 0; j < sband->n_bitrates; j++)
+			if (sband->bitrates[j].bitrate == bitrate)
+				rates |= BIT(j);
 	}
+	ifsta->supp_rates_bits[local->hw.conf.channel->band] = rates;
+
+	ieee80211_sta_def_wmm_params(dev, bss, 1);
 
 	ifsta->state = IEEE80211_IBSS_JOINED;
 	mod_timer(&ifsta->timer, jiffies + IEEE80211_IBSS_MERGE_INTERVAL);
@@ -3333,7 +3289,7 @@ static void ieee80211_mesh_housekeeping(struct net_device *dev,
 
 	free_plinks = mesh_plink_availables(sdata);
 	if (free_plinks != sdata->u.sta.accepting_plinks)
-		ieee80211_if_config_beacon(dev);
+		ieee80211_if_config(sdata, IEEE80211_IFCC_BEACON);
 
 	mod_timer(&ifsta->timer, jiffies +
 			IEEE80211_MESH_HOUSEKEEPING_INTERVAL);
@@ -3757,28 +3713,45 @@ int ieee80211_sta_set_ssid(struct net_device *dev, char *ssid, size_t len)
 {
 	struct ieee80211_sub_if_data *sdata = IEEE80211_DEV_TO_SUB_IF(dev);
 	struct ieee80211_if_sta *ifsta;
+	int res;
 
 	if (len > IEEE80211_MAX_SSID_LEN)
 		return -EINVAL;
 
 	ifsta = &sdata->u.sta;
 
-	if (ifsta->ssid_len != len || memcmp(ifsta->ssid, ssid, len) != 0)
+	if (ifsta->ssid_len != len || memcmp(ifsta->ssid, ssid, len) != 0) {
+		memset(ifsta->ssid, 0, sizeof(ifsta->ssid));
+		memcpy(ifsta->ssid, ssid, len);
+		ifsta->ssid_len = len;
 		ifsta->flags &= ~IEEE80211_STA_PREV_BSSID_SET;
-	memcpy(ifsta->ssid, ssid, len);
-	memset(ifsta->ssid + len, 0, IEEE80211_MAX_SSID_LEN - len);
-	ifsta->ssid_len = len;
+
+		res = 0;
+		/*
+		 * Hack! MLME code needs to be cleaned up to have different
+		 * entry points for configuration and internal selection change
+		 */
+		if (netif_running(sdata->dev))
+			res = ieee80211_if_config(sdata, IEEE80211_IFCC_SSID);
+		if (res) {
+			printk(KERN_DEBUG "%s: Failed to config new SSID to "
+			       "the low-level driver\n", dev->name);
+			return res;
+		}
+	}
 
 	if (len)
 		ifsta->flags |= IEEE80211_STA_SSID_SET;
 	else
 		ifsta->flags &= ~IEEE80211_STA_SSID_SET;
+
 	if (sdata->vif.type == IEEE80211_IF_TYPE_IBSS &&
 	    !(ifsta->flags & IEEE80211_STA_BSSID_SET)) {
 		ifsta->ibss_join_req = jiffies;
 		ifsta->state = IEEE80211_IBSS_SEARCH;
 		return ieee80211_sta_find_ibss(dev, ifsta);
 	}
+
 	return 0;
 }
 
@@ -3804,7 +3777,12 @@ int ieee80211_sta_set_bssid(struct net_device *dev, u8 *bssid)
 
 	if (memcmp(ifsta->bssid, bssid, ETH_ALEN) != 0) {
 		memcpy(ifsta->bssid, bssid, ETH_ALEN);
-		res = ieee80211_if_config(dev);
+		res = 0;
+		/*
+		 * Hack! See also ieee80211_sta_set_ssid.
+		 */
+		if (netif_running(sdata->dev))
+			res = ieee80211_if_config(sdata, IEEE80211_IFCC_BSSID);
 		if (res) {
 			printk(KERN_DEBUG "%s: Failed to config new BSSID to "
 			       "the low-level driver\n", dev->name);
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index a757dcc..8843416 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -1788,17 +1788,17 @@ struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
 				     struct ieee80211_vif *vif)
 {
 	struct ieee80211_local *local = hw_to_local(hw);
-	struct sk_buff *skb;
+	struct sk_buff *skb = NULL;
 	struct ieee80211_tx_info *info;
 	struct net_device *bdev;
 	struct ieee80211_sub_if_data *sdata = NULL;
 	struct ieee80211_if_ap *ap = NULL;
+	struct ieee80211_if_sta *ifsta = NULL;
 	struct rate_selection rsel;
 	struct beacon_data *beacon;
 	struct ieee80211_supported_band *sband;
 	struct ieee80211_mgmt *mgmt;
 	int *num_beacons;
-	bool err = true;
 	enum ieee80211_band band = local->hw.conf.channel->band;
 	u8 *pos;
 
@@ -1852,9 +1852,24 @@ struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
 				       beacon->tail, beacon->tail_len);
 
 			num_beacons = &ap->num_beacons;
+		} else
+			goto out;
+	} else if (sdata->vif.type == IEEE80211_IF_TYPE_IBSS) {
+		struct ieee80211_hdr *hdr;
+		ifsta = &sdata->u.sta;
 
-			err = false;
-		}
+		if (!ifsta->probe_resp)
+			goto out;
+
+		skb = skb_copy(ifsta->probe_resp, GFP_ATOMIC);
+		if (!skb)
+			goto out;
+
+		hdr = (struct ieee80211_hdr *) skb->data;
+		hdr->frame_control = IEEE80211_FC(IEEE80211_FTYPE_MGMT,
+						  IEEE80211_STYPE_BEACON);
+
+		num_beacons = &ifsta->num_beacons;
 	} else if (ieee80211_vif_is_mesh(&sdata->vif)) {
 		/* headroom, head length, tail length and maximum TIM length */
 		skb = dev_alloc_skb(local->tx_headroom + 400);
@@ -1881,17 +1896,8 @@ struct sk_buff *ieee80211_beacon_get(struct ieee80211_hw *hw,
 		mesh_mgmt_ies_add(skb, sdata->dev);
 
 		num_beacons = &sdata->u.sta.num_beacons;
-
-		err = false;
-	}
-
-	if (err) {
-#ifdef CONFIG_MAC80211_VERBOSE_DEBUG
-		if (net_ratelimit())
-			printk(KERN_DEBUG "no beacon data avail for %s\n",
-			       bdev->name);
-#endif /* CONFIG_MAC80211_VERBOSE_DEBUG */
-		skb = NULL;
+	} else {
+		WARN_ON(1);
 		goto out;
 	}
 
diff --git a/net/mac80211/wext.c b/net/mac80211/wext.c
index c041db9..34fa8ed 100644
--- a/net/mac80211/wext.c
+++ b/net/mac80211/wext.c
@@ -444,7 +444,7 @@ static int ieee80211_ioctl_siwessid(struct net_device *dev,
 		memset(sdata->u.ap.ssid + len, 0,
 		       IEEE80211_MAX_SSID_LEN - len);
 		sdata->u.ap.ssid_len = len;
-		return ieee80211_if_config(dev);
+		return ieee80211_if_config(sdata, IEEE80211_IFCC_SSID);
 	}
 	return -EOPNOTSUPP;
 }