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 ea0301025c1..8e7ba0e62cf 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 2146c0c436d..934c3ef4f0b 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 0759ab2ca3f..36859e79492 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 64d710a88b8..61d7f81bf45 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 a757dcc1208..8843416e146 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 c041db9556c..34fa8ed1e78 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;
 }