1 files changed, 116 insertions, 26 deletions

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index a0e00c6339ca..906ab785db40 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -984,9 +984,9 @@ __ieee80211_tx_prepare(struct ieee80211_tx_data *tx,
         struct ieee80211_hdr *hdr;
         struct ieee80211_sub_if_data *sdata;
         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
-
         int hdrlen, tid;
         u8 *qc, *state;
+        bool queued = false;
 
         memset(tx, 0, sizeof(*tx));
         tx->skb = skb;
@@ -1013,20 +1013,53 @@ __ieee80211_tx_prepare(struct ieee80211_tx_data *tx,
                  */
         }
 
+        /*
+         * If this flag is set to true anywhere, and we get here,
+         * we are doing the needed processing, so remove the flag
+         * now.
+         */
+        info->flags &= ~IEEE80211_TX_INTFL_NEED_TXPROCESSING;
+
         hdr = (struct ieee80211_hdr *) skb->data;
 
         tx->sta = sta_info_get(local, hdr->addr1);
 
-        if (tx->sta && ieee80211_is_data_qos(hdr->frame_control)) {
+        if (tx->sta && ieee80211_is_data_qos(hdr->frame_control) &&
+            (local->hw.flags & IEEE80211_HW_AMPDU_AGGREGATION)) {
                 unsigned long flags;
+                struct tid_ampdu_tx *tid_tx;
+
                 qc = ieee80211_get_qos_ctl(hdr);
                 tid = *qc & IEEE80211_QOS_CTL_TID_MASK;
 
                 spin_lock_irqsave(&tx->sta->lock, flags);
+                /*
+                 * XXX: This spinlock could be fairly expensive, but see the
+                 *      comment in agg-tx.c:ieee80211_agg_tx_operational().
+                 *      One way to solve this would be to do something RCU-like
+                 *      for managing the tid_tx struct and using atomic bitops
+                 *      for the actual state -- by introducing an actual
+                 *      'operational' bit that would be possible. It would
+                 *      require changing ieee80211_agg_tx_operational() to
+                 *      set that bit, and changing the way tid_tx is managed
+                 *      everywhere, including races between that bit and
+                 *      tid_tx going away (tid_tx being added can be easily
+                 *      committed to memory before the 'operational' bit).
+                 */
+                tid_tx = tx->sta->ampdu_mlme.tid_tx[tid];
                 state = &tx->sta->ampdu_mlme.tid_state_tx[tid];
-                if (*state == HT_AGG_STATE_OPERATIONAL)
+                if (*state == HT_AGG_STATE_OPERATIONAL) {
                         info->flags |= IEEE80211_TX_CTL_AMPDU;
+                } else if (*state != HT_AGG_STATE_IDLE) {
+                        /* in progress */
+                        queued = true;
+                        info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
+                        __skb_queue_tail(&tid_tx->pending, skb);
+                }
                 spin_unlock_irqrestore(&tx->sta->lock, flags);
+
+                if (unlikely(queued))
+                        return TX_QUEUED;
         }
 
         if (is_multicast_ether_addr(hdr->addr1)) {
@@ -1077,7 +1110,14 @@ static int ieee80211_tx_prepare(struct ieee80211_local *local,
         }
         if (unlikely(!dev))
                 return -ENODEV;
-        /* initialises tx with control */
+        /*
+         * initialises tx with control
+         *
+         * return value is safe to ignore here because this function
+         * can only be invoked for multicast frames
+         *
+         * XXX: clean up
+         */
         __ieee80211_tx_prepare(tx, skb, dev);
         dev_put(dev);
         return 0;
@@ -1188,7 +1228,8 @@ static int invoke_tx_handlers(struct ieee80211_tx_data *tx)
         return 0;
 }
 
-static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb)
+static void ieee80211_tx(struct net_device *dev, struct sk_buff *skb,
+                         bool txpending)
 {
         struct ieee80211_local *local = wdev_priv(dev->ieee80211_ptr);
         struct sta_info *sta;
@@ -1202,11 +1243,11 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb)
 
         queue = skb_get_queue_mapping(skb);
 
-        WARN_ON(!skb_queue_empty(&local->pending[queue]));
+        WARN_ON(!txpending && !skb_queue_empty(&local->pending[queue]));
 
         if (unlikely(skb->len < 10)) {
                 dev_kfree_skb(skb);
-                return 0;
+                return;
         }
 
         rcu_read_lock();
@@ -1214,10 +1255,13 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb)
         /* initialises tx */
         res_prepare = __ieee80211_tx_prepare(&tx, skb, dev);
 
-        if (res_prepare == TX_DROP) {
+        if (unlikely(res_prepare == TX_DROP)) {
                 dev_kfree_skb(skb);
                 rcu_read_unlock();
-                return 0;
+                return;
+        } else if (unlikely(res_prepare == TX_QUEUED)) {
+                rcu_read_unlock();
+                return;
         }
 
         sta = tx.sta;
@@ -1251,7 +1295,12 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb)
                         do {
                                 next = skb->next;
                                 skb->next = NULL;
-                                skb_queue_tail(&local->pending[queue], skb);
+                                if (unlikely(txpending))
+                                        skb_queue_head(&local->pending[queue],
+                                                       skb);
+                                else
+                                        skb_queue_tail(&local->pending[queue],
+                                                       skb);
                         } while ((skb = next));
 
                         /*
@@ -1276,7 +1325,7 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb)
         }
  out:
         rcu_read_unlock();
-        return 0;
+        return;
 
  drop:
         rcu_read_unlock();
@@ -1287,7 +1336,6 @@ static int ieee80211_tx(struct net_device *dev, struct sk_buff *skb)
                 dev_kfree_skb(skb);
                 skb = next;
         }
-        return 0;
 }
 
 /* device xmit handlers */
@@ -1346,7 +1394,6 @@ int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 FOUND_SDATA,
                 UNKNOWN_ADDRESS,
         } monitor_iface = NOT_MONITOR;
-        int ret;
 
         if (skb->iif)
                 odev = dev_get_by_index(&init_net, skb->iif);
@@ -1360,7 +1407,7 @@ int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev)
                        "originating device\n", dev->name);
 #endif
                 dev_kfree_skb(skb);
-                return 0;
+                return NETDEV_TX_OK;
         }
 
         if ((local->hw.flags & IEEE80211_HW_PS_NULLFUNC_STACK) &&
@@ -1389,7 +1436,7 @@ int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 else
                         if (mesh_nexthop_lookup(skb, osdata)) {
                                 dev_put(odev);
-                                return 0;
+                                return NETDEV_TX_OK;
                         }
                 if (memcmp(odev->dev_addr, hdr->addr4, ETH_ALEN) != 0)
                         IEEE80211_IFSTA_MESH_CTR_INC(&osdata->u.mesh,
@@ -1451,7 +1498,7 @@ int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev)
         if (ieee80211_skb_resize(osdata->local, skb, headroom, may_encrypt)) {
                 dev_kfree_skb(skb);
                 dev_put(odev);
-                return 0;
+                return NETDEV_TX_OK;
         }
 
         if (osdata->vif.type == NL80211_IFTYPE_AP_VLAN)
@@ -1460,10 +1507,11 @@ int ieee80211_master_start_xmit(struct sk_buff *skb, struct net_device *dev)
                                       u.ap);
         if (likely(monitor_iface != UNKNOWN_ADDRESS))
                 info->control.vif = &osdata->vif;
-        ret = ieee80211_tx(odev, skb);
+
+        ieee80211_tx(odev, skb, false);
         dev_put(odev);
 
-        return ret;
+        return NETDEV_TX_OK;
 }
 
 int ieee80211_monitor_start_xmit(struct sk_buff *skb,
@@ -1827,6 +1875,54 @@ void ieee80211_clear_tx_pending(struct ieee80211_local *local)
                 skb_queue_purge(&local->pending[i]);
 }
 
+static bool ieee80211_tx_pending_skb(struct ieee80211_local *local,
+                                     struct sk_buff *skb)
+{
+        struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+        struct ieee80211_sub_if_data *sdata;
+        struct sta_info *sta;
+        struct ieee80211_hdr *hdr;
+        struct net_device *dev;
+        int ret;
+        bool result = true;
+
+        /* does interface still exist? */
+        dev = dev_get_by_index(&init_net, skb->iif);
+        if (!dev) {
+                dev_kfree_skb(skb);
+                return true;
+        }
+
+        /* validate info->control.vif against skb->iif */
+        sdata = IEEE80211_DEV_TO_SUB_IF(dev);
+        if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
+                sdata = container_of(sdata->bss,
+                                     struct ieee80211_sub_if_data,
+                                     u.ap);
+
+        if (unlikely(info->control.vif && info->control.vif != &sdata->vif)) {
+                dev_kfree_skb(skb);
+                result = true;
+                goto out;
+        }
+
+        if (info->flags & IEEE80211_TX_INTFL_NEED_TXPROCESSING) {
+                ieee80211_tx(dev, skb, true);
+        } else {
+                hdr = (struct ieee80211_hdr *)skb->data;
+                sta = sta_info_get(local, hdr->addr1);
+
+                ret = __ieee80211_tx(local, &skb, sta);
+                if (ret != IEEE80211_TX_OK)
+                        result = false;
+        }
+
+ out:
+        dev_put(dev);
+
+        return result;
+}
+
 /*
  * Transmit all pending packets. Called from tasklet, locks master device
  * TX lock so that no new packets can come in.
@@ -1835,9 +1931,8 @@ void ieee80211_tx_pending(unsigned long data)
 {
         struct ieee80211_local *local = (struct ieee80211_local *)data;
         struct net_device *dev = local->mdev;
-        struct ieee80211_hdr *hdr;
         unsigned long flags;
-        int i, ret;
+        int i;
         bool next;
 
         rcu_read_lock();
@@ -1868,13 +1963,8 @@ void ieee80211_tx_pending(unsigned long data)
 
                 while (!skb_queue_empty(&local->pending[i])) {
                         struct sk_buff *skb = skb_dequeue(&local->pending[i]);
-                        struct sta_info *sta;
-
-                        hdr = (struct ieee80211_hdr *)skb->data;
-                        sta = sta_info_get(local, hdr->addr1);
 
-                        ret = __ieee80211_tx(local, &skb, sta);
-                        if (ret != IEEE80211_TX_OK) {
+                        if (!ieee80211_tx_pending_skb(local, skb)) {
                                 skb_queue_head(&local->pending[i], skb);
                                 break;
                         }