mac80211: merge an upstream fix for an aggregation related race condition
authorFelix Fietkau <nbd@openwrt.org>
Sat, 10 Dec 2011 21:16:58 +0000 (21:16 +0000)
committerFelix Fietkau <nbd@openwrt.org>
Sat, 10 Dec 2011 21:16:58 +0000 (21:16 +0000)
SVN-Revision: 29493

package/mac80211/patches/300-pending_work.patch

index 34de3ac..2119b42 100644 (file)
  
        mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
                                          IEEE80211_STYPE_ACTION);
-@@ -437,7 +440,9 @@ int ieee80211_start_tx_ba_session(struct
+@@ -319,6 +322,38 @@ ieee80211_wake_queue_agg(struct ieee8021
+       __release(agg_queue);
+ }
++/*
++ * splice packets from the STA's pending to the local pending,
++ * requires a call to ieee80211_agg_splice_finish later
++ */
++static void __acquires(agg_queue)
++ieee80211_agg_splice_packets(struct ieee80211_local *local,
++                           struct tid_ampdu_tx *tid_tx, u16 tid)
++{
++      int queue = ieee80211_ac_from_tid(tid);
++      unsigned long flags;
++
++      ieee80211_stop_queue_agg(local, tid);
++
++      if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates"
++                        " from the pending queue\n", tid))
++              return;
++
++      if (!skb_queue_empty(&tid_tx->pending)) {
++              spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
++              /* copy over remaining packets */
++              skb_queue_splice_tail_init(&tid_tx->pending,
++                                         &local->pending[queue]);
++              spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
++      }
++}
++
++static void __releases(agg_queue)
++ieee80211_agg_splice_finish(struct ieee80211_local *local, u16 tid)
++{
++      ieee80211_wake_queue_agg(local, tid);
++}
++
+ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
+ {
+       struct tid_ampdu_tx *tid_tx;
+@@ -330,19 +365,17 @@ void ieee80211_tx_ba_session_handle_star
+       tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
+       /*
+-       * While we're asking the driver about the aggregation,
+-       * stop the AC queue so that we don't have to worry
+-       * about frames that came in while we were doing that,
+-       * which would require us to put them to the AC pending
+-       * afterwards which just makes the code more complex.
++       * Start queuing up packets for this aggregation session.
++       * We're going to release them once the driver is OK with
++       * that.
+        */
+-      ieee80211_stop_queue_agg(local, tid);
+-
+       clear_bit(HT_AGG_STATE_WANT_START, &tid_tx->state);
+       /*
+-       * make sure no packets are being processed to get
+-       * valid starting sequence number
++       * Make sure no packets are being processed. This ensures that
++       * we have a valid starting sequence number and that in-flight
++       * packets have been flushed out and no packets for this TID
++       * will go into the driver during the ampdu_action call.
+        */
+       synchronize_net();
+@@ -356,10 +389,11 @@ void ieee80211_tx_ba_session_handle_star
+                                       " tid %d\n", tid);
+ #endif
+               spin_lock_bh(&sta->lock);
++              ieee80211_agg_splice_packets(local, tid_tx, tid);
+               ieee80211_assign_tid_tx(sta, tid, NULL);
++              ieee80211_agg_splice_finish(local, tid);
+               spin_unlock_bh(&sta->lock);
+-              ieee80211_wake_queue_agg(local, tid);
+ #if (LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,40))
+               kfree_rcu(tid_tx, rcu_head);
+ #else
+@@ -368,9 +402,6 @@ void ieee80211_tx_ba_session_handle_star
+               return;
+       }
+-      /* we can take packets again now */
+-      ieee80211_wake_queue_agg(local, tid);
+-
+       /* activate the timer for the recipient's addBA response */
+       mod_timer(&tid_tx->addba_resp_timer, jiffies + ADDBA_RESP_INTERVAL);
+ #ifdef CONFIG_MAC80211_HT_DEBUG
+@@ -437,7 +468,9 @@ int ieee80211_start_tx_ba_session(struct
        if (sdata->vif.type != NL80211_IFTYPE_STATION &&
            sdata->vif.type != NL80211_IFTYPE_MESH_POINT &&
            sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
                return -EINVAL;
  
        if (test_sta_flag(sta, WLAN_STA_BLOCK_BA)) {
-@@ -448,6 +453,27 @@ int ieee80211_start_tx_ba_session(struct
+@@ -448,6 +481,27 @@ int ieee80211_start_tx_ba_session(struct
                return -EINVAL;
        }
  
        spin_lock_bh(&sta->lock);
  
        /* we have tried too many times, receiver does not want A-MPDU */
+@@ -508,38 +562,6 @@ int ieee80211_start_tx_ba_session(struct
+ }
+ EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
+-/*
+- * splice packets from the STA's pending to the local pending,
+- * requires a call to ieee80211_agg_splice_finish later
+- */
+-static void __acquires(agg_queue)
+-ieee80211_agg_splice_packets(struct ieee80211_local *local,
+-                           struct tid_ampdu_tx *tid_tx, u16 tid)
+-{
+-      int queue = ieee80211_ac_from_tid(tid);
+-      unsigned long flags;
+-
+-      ieee80211_stop_queue_agg(local, tid);
+-
+-      if (WARN(!tid_tx, "TID %d gone but expected when splicing aggregates"
+-                        " from the pending queue\n", tid))
+-              return;
+-
+-      if (!skb_queue_empty(&tid_tx->pending)) {
+-              spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
+-              /* copy over remaining packets */
+-              skb_queue_splice_tail_init(&tid_tx->pending,
+-                                         &local->pending[queue]);
+-              spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+-      }
+-}
+-
+-static void __releases(agg_queue)
+-ieee80211_agg_splice_finish(struct ieee80211_local *local, u16 tid)
+-{
+-      ieee80211_wake_queue_agg(local, tid);
+-}
+-
+ static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
+                                        struct sta_info *sta, u16 tid)
+ {
 --- a/net/mac80211/debugfs_sta.c
 +++ b/net/mac80211/debugfs_sta.c
 @@ -63,11 +63,11 @@ static ssize_t sta_flags_read(struct fil