mac80211: split TX aggregation stop action

When TX aggregation is stopped, there are a few
different cases:
 - connection with the peer was dropped
 - session stop was requested locally
 - session stop was requested by the peer
 - connection was dropped while a session is stopping

The behaviour in these cases should be different, if
the connection is dropped then the driver should drop
all frames, otherwise the frames may continue to be
transmitted, aggregated in the case of a locally
requested session stop or unaggregated in the case of
the peer requesting session stop.

Split these different cases so that the driver can
act accordingly; however, treat local and remote stop
the same way and ask the driver to not send frames as
aggregated packets any more.

In the case of connection drop, the stop callback the
driver is otherwise supposed to call is no longer
required.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

13 files changed, 85 insertions, 21 deletions

diff --git a/drivers/net/wireless/ath/ath9k/htc_drv_main.c b/drivers/net/wireless/ath/ath9k/htc_drv_main.c
index 9c07a8fa5134..a8016d70088a 100644
--- a/drivers/net/wireless/ath/ath9k/htc_drv_main.c
+++ b/drivers/net/wireless/ath/ath9k/htc_drv_main.c
@@ -1628,7 +1628,9 @@ static int ath9k_htc_ampdu_action(struct ieee80211_hw *hw,
                 if (!ret)
                         ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 break;
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 ath9k_htc_tx_aggr_oper(priv, vif, sta, action, tid);
                 ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 break;
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index be30a9af1528..e1fa70596e61 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1610,7 +1610,9 @@ static int ath9k_ampdu_action(struct ieee80211_hw *hw,
                         ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 ath9k_ps_restore(sc);
                 break;
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 ath9k_ps_wakeup(sc);
                 ath_tx_aggr_stop(sc, sta, tid);
                 ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
diff --git a/drivers/net/wireless/ath/carl9170/main.c b/drivers/net/wireless/ath/carl9170/main.c
index 25a1e2f4f738..9d2051aeb782 100644
--- a/drivers/net/wireless/ath/carl9170/main.c
+++ b/drivers/net/wireless/ath/carl9170/main.c
@@ -1394,7 +1394,9 @@ static int carl9170_op_ampdu_action(struct ieee80211_hw *hw,
                 ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 break;
 
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 rcu_read_lock();
                 tid_info = rcu_dereference(sta_info->agg[tid]);
                 if (tid_info) {
diff --git a/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c b/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
index 1fbd8ecbe2ea..f0fc8cd4d5df 100644
--- a/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
+++ b/drivers/net/wireless/brcm80211/brcmsmac/mac80211_if.c
@@ -668,7 +668,9 @@ brcms_ops_ampdu_action(struct ieee80211_hw *hw,
                 ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 break;
 
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 spin_lock_bh(&wl->lock);
                 brcms_c_ampdu_flush(wl->wlc, sta, tid);
                 spin_unlock_bh(&wl->lock);
diff --git a/drivers/net/wireless/iwlegacy/4965-mac.c b/drivers/net/wireless/iwlegacy/4965-mac.c
index c3fbf6717564..6a86ed45835d 100644
--- a/drivers/net/wireless/iwlegacy/4965-mac.c
+++ b/drivers/net/wireless/iwlegacy/4965-mac.c
@@ -5968,7 +5968,9 @@ il4965_mac_ampdu_action(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                 D_HT("start Tx\n");
                 ret = il4965_tx_agg_start(il, vif, sta, tid, ssn);
                 break;
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 D_HT("stop Tx\n");
                 ret = il4965_tx_agg_stop(il, vif, sta, tid);
                 if (test_bit(S_EXIT_PENDING, &il->status))
diff --git a/drivers/net/wireless/iwlwifi/dvm/mac80211.c b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
index 3163e0f38c25..02fdcea76b21 100644
--- a/drivers/net/wireless/iwlwifi/dvm/mac80211.c
+++ b/drivers/net/wireless/iwlwifi/dvm/mac80211.c
@@ -679,7 +679,9 @@ static int iwlagn_mac_ampdu_action(struct ieee80211_hw *hw,
                 IWL_DEBUG_HT(priv, "start Tx\n");
                 ret = iwlagn_tx_agg_start(priv, vif, sta, tid, ssn);
                 break;
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 IWL_DEBUG_HT(priv, "stop Tx\n");
                 ret = iwlagn_tx_agg_stop(priv, vif, sta, tid);
                 if ((ret == 0) && (priv->agg_tids_count > 0)) {
diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c
index 145498f8411f..d248a4cc6656 100644
--- a/drivers/net/wireless/mac80211_hwsim.c
+++ b/drivers/net/wireless/mac80211_hwsim.c
@@ -1312,7 +1312,9 @@ static int mac80211_hwsim_ampdu_action(struct ieee80211_hw *hw,
         case IEEE80211_AMPDU_TX_START:
                 ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 break;
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 break;
         case IEEE80211_AMPDU_TX_OPERATIONAL:
diff --git a/drivers/net/wireless/mwl8k.c b/drivers/net/wireless/mwl8k.c
index f221b95b90b3..19b46fdf9f0f 100644
--- a/drivers/net/wireless/mwl8k.c
+++ b/drivers/net/wireless/mwl8k.c
@@ -5170,7 +5170,9 @@ mwl8k_ampdu_action(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
                 }
                 ieee80211_start_tx_ba_cb_irqsafe(vif, addr, tid);
                 break;
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 if (stream) {
                         if (stream->state == AMPDU_STREAM_ACTIVE) {
                                 spin_unlock(&priv->stream_lock);
diff --git a/drivers/net/wireless/rt2x00/rt2800lib.c b/drivers/net/wireless/rt2x00/rt2800lib.c
index 197b4466a5d2..12f93e42e160 100644
--- a/drivers/net/wireless/rt2x00/rt2800lib.c
+++ b/drivers/net/wireless/rt2x00/rt2800lib.c
@@ -5484,7 +5484,9 @@ int rt2800_ampdu_action(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
         case IEEE80211_AMPDU_TX_START:
                 ieee80211_start_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 break;
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 ieee80211_stop_tx_ba_cb_irqsafe(vif, sta->addr, tid);
                 break;
         case IEEE80211_AMPDU_TX_OPERATIONAL:
diff --git a/drivers/net/wireless/rtlwifi/core.c b/drivers/net/wireless/rtlwifi/core.c
index be33aa14c8af..d3ce9fbef00e 100644
--- a/drivers/net/wireless/rtlwifi/core.c
+++ b/drivers/net/wireless/rtlwifi/core.c
@@ -879,7 +879,9 @@ static int rtl_op_ampdu_action(struct ieee80211_hw *hw,
                          "IEEE80211_AMPDU_TX_START: TID:%d\n", tid);
                 return rtl_tx_agg_start(hw, sta, tid, ssn);
                 break;
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
                 RT_TRACE(rtlpriv, COMP_MAC80211, DBG_TRACE,
                          "IEEE80211_AMPDU_TX_STOP: TID:%d\n", tid);
                 return rtl_tx_agg_stop(hw, sta, tid);
diff --git a/drivers/net/wireless/ti/wlcore/main.c b/drivers/net/wireless/ti/wlcore/main.c
index ea9d8e011bc9..d7de06359ae1 100644
--- a/drivers/net/wireless/ti/wlcore/main.c
+++ b/drivers/net/wireless/ti/wlcore/main.c
@@ -4575,7 +4575,9 @@ static int wl1271_op_ampdu_action(struct ieee80211_hw *hw,
          * Falling break here on purpose for all TX APDU commands.
          */
         case IEEE80211_AMPDU_TX_START:
-        case IEEE80211_AMPDU_TX_STOP:
+        case IEEE80211_AMPDU_TX_STOP_CONT:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH:
+        case IEEE80211_AMPDU_TX_STOP_FLUSH_CONT:
         case IEEE80211_AMPDU_TX_OPERATIONAL:
                 ret = -EINVAL;
                 break;
diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 0978b0faa880..a464f4fb36a0 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -2033,17 +2033,29 @@ enum ieee80211_filter_flags {
  * calling ieee80211_start_tx_ba_cb_irqsafe, because the peer
  * might receive the addBA frame and send a delBA right away!
  *
- * @IEEE80211_AMPDU_RX_START: start Rx aggregation
- * @IEEE80211_AMPDU_RX_STOP: stop Rx aggregation
- * @IEEE80211_AMPDU_TX_START: start Tx aggregation
- * @IEEE80211_AMPDU_TX_STOP: stop Tx aggregation
+ * @IEEE80211_AMPDU_RX_START: start RX aggregation
+ * @IEEE80211_AMPDU_RX_STOP: stop RX aggregation
+ * @IEEE80211_AMPDU_TX_START: start TX aggregation
  * @IEEE80211_AMPDU_TX_OPERATIONAL: TX aggregation has become operational
+ * @IEEE80211_AMPDU_TX_STOP_CONT: stop TX aggregation but continue transmitting
+ *      queued packets, now unaggregated. After all packets are transmitted the
+ *      driver has to call ieee80211_stop_tx_ba_cb_irqsafe().
+ * @IEEE80211_AMPDU_TX_STOP_FLUSH: stop TX aggregation and flush all packets,
+ *      called when the station is removed. There's no need or reason to call
+ *      ieee80211_stop_tx_ba_cb_irqsafe() in this case as mac80211 assumes the
+ *      session is gone and removes the station.
+ * @IEEE80211_AMPDU_TX_STOP_FLUSH_CONT: called when TX aggregation is stopped
+ *      but the driver hasn't called ieee80211_stop_tx_ba_cb_irqsafe() yet and
+ *      now the connection is dropped and the station will be removed. Drivers
+ *      should clean up and drop remaining packets when this is called.
  */
 enum ieee80211_ampdu_mlme_action {
         IEEE80211_AMPDU_RX_START,
         IEEE80211_AMPDU_RX_STOP,
         IEEE80211_AMPDU_TX_START,
-        IEEE80211_AMPDU_TX_STOP,
+        IEEE80211_AMPDU_TX_STOP_CONT,
+        IEEE80211_AMPDU_TX_STOP_FLUSH,
+        IEEE80211_AMPDU_TX_STOP_FLUSH_CONT,
         IEEE80211_AMPDU_TX_OPERATIONAL,
 };
 
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index dda8d7df4b54..2f0ccbc5f13e 100644
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -257,10 +257,25 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
 {
         struct ieee80211_local *local = sta->local;
         struct tid_ampdu_tx *tid_tx;
+        enum ieee80211_ampdu_mlme_action action;
         int ret;
 
         lockdep_assert_held(&sta->ampdu_mlme.mtx);
 
+        switch (reason) {
+        case AGG_STOP_DECLINED:
+        case AGG_STOP_LOCAL_REQUEST:
+        case AGG_STOP_PEER_REQUEST:
+                action = IEEE80211_AMPDU_TX_STOP_CONT;
+                break;
+        case AGG_STOP_DESTROY_STA:
+                action = IEEE80211_AMPDU_TX_STOP_FLUSH;
+                break;
+        default:
+                WARN_ON_ONCE(1);
+                return -EINVAL;
+        }
+
         spin_lock_bh(&sta->lock);
 
         tid_tx = rcu_dereference_protected_tid_tx(sta, tid);
@@ -269,10 +284,19 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
                 return -ENOENT;
         }
 
-        /* if we're already stopping ignore any new requests to stop */
+        /*
+         * if we're already stopping ignore any new requests to stop
+         * unless we're destroying it in which case notify the driver
+         */
         if (test_bit(HT_AGG_STATE_STOPPING, &tid_tx->state)) {
                 spin_unlock_bh(&sta->lock);
-                return -EALREADY;
+                if (reason != AGG_STOP_DESTROY_STA)
+                        return -EALREADY;
+                ret = drv_ampdu_action(local, sta->sdata,
+                                       IEEE80211_AMPDU_TX_STOP_FLUSH_CONT,
+                                       &sta->sta, tid, NULL, 0);
+                WARN_ON_ONCE(ret);
+                goto remove_tid_tx;
         }
 
         if (test_bit(HT_AGG_STATE_WANT_START, &tid_tx->state)) {
@@ -319,8 +343,7 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
                                         WLAN_BACK_INITIATOR;
         tid_tx->tx_stop = reason == AGG_STOP_LOCAL_REQUEST;
 
-        ret = drv_ampdu_action(local, sta->sdata,
-                               IEEE80211_AMPDU_TX_STOP,
+        ret = drv_ampdu_action(local, sta->sdata, action,
                                &sta->sta, tid, NULL, 0);
 
         /* HW shall not deny going back to legacy */
@@ -331,7 +354,14 @@ int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
                  */
         }
 
-        return ret;
+        if (reason == AGG_STOP_DESTROY_STA) {
+ remove_tid_tx:
+                spin_lock_bh(&sta->lock);
+                ieee80211_remove_tid_tx(sta, tid);
+                spin_unlock_bh(&sta->lock);
+        }
+
+        return 0;
 }
 
 /*