iwlwifi: mvm: cleanup pending frames in DQA mode

When a station is asleep, the fw will set it as "asleep".
All queues that are used only by one station will be stopped by
the fw.

In pre-DQA mode this was relevant for aggregation queues. However,
in DQA mode a queue is owned by one station only, so all queues
will be stopped.
As a result, we don't expect to get filtered frames back to
mac80211 and don't have to maintain the entire pending_frames
state logic, the same way as we do in aggregations.

The correct behavior is to align DQA behavior with the aggregation
queue behaviour pre-DQA:
- Don't count pending frames.
- Let mac80211 know we have frames in these queues so that it can
properly handle trigger frames.

When a trigger frame is received, mac80211 tells the driver to send
frames from the queues using release_buffered_frames.
The driver will tell the fw to let frames out even if the station
is asleep. This is done by iwl_mvm_sta_modify_sleep_tx_count.

Reported-and-tested-by: Jens Axboe <axboe@kernel.dk>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

4 files changed, 28 insertions, 31 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index d37b1695c64e..6927caecd48e 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -2319,7 +2319,7 @@ iwl_mvm_mac_release_buffered_frames(struct ieee80211_hw *hw,
 {
         struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw);
 
-        /* Called when we need to transmit (a) frame(s) from agg queue */
+        /* Called when we need to transmit (a) frame(s) from agg or dqa queue */
 
         iwl_mvm_sta_modify_sleep_tx_count(mvm, sta, reason, num_frames,
                                           tids, more_data, true);
@@ -2338,7 +2338,8 @@ static void __iwl_mvm_mac_sta_notify(struct ieee80211_hw *hw,
         for (tid = 0; tid < IWL_MAX_TID_COUNT; tid++) {
                 struct iwl_mvm_tid_data *tid_data = &mvmsta->tid_data[tid];
 
-                if (tid_data->state != IWL_AGG_ON &&
+                if (!iwl_mvm_is_dqa_supported(mvm) &&
+                    tid_data->state != IWL_AGG_ON &&
                     tid_data->state != IWL_EMPTYING_HW_QUEUE_DELBA)
                         continue;
 
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
index bd1dcc863d8f..b51a2853cc80 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.c
@@ -3135,7 +3135,7 @@ void iwl_mvm_sta_modify_sleep_tx_count(struct iwl_mvm *mvm,
                                        struct ieee80211_sta *sta,
                                        enum ieee80211_frame_release_type reason,
                                        u16 cnt, u16 tids, bool more_data,
-                                       bool agg)
+                                       bool single_sta_queue)
 {
         struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
         struct iwl_mvm_add_sta_cmd cmd = {
@@ -3155,14 +3155,14 @@ void iwl_mvm_sta_modify_sleep_tx_count(struct iwl_mvm *mvm,
         for_each_set_bit(tid, &_tids, IWL_MAX_TID_COUNT)
                 cmd.awake_acs |= BIT(tid_to_ucode_ac[tid]);
 
-        /* If we're releasing frames from aggregation queues then check if the
-         * all queues combined that we're releasing frames from have
+        /* If we're releasing frames from aggregation or dqa queues then check
+         * if all the queues that we're releasing frames from, combined, have:
          *  - more frames than the service period, in which case more_data
          *    needs to be set
          *  - fewer than 'cnt' frames, in which case we need to adjust the
          *    firmware command (but do that unconditionally)
          */
-        if (agg) {
+        if (single_sta_queue) {
                 int remaining = cnt;
                 int sleep_tx_count;
 
@@ -3172,7 +3172,8 @@ void iwl_mvm_sta_modify_sleep_tx_count(struct iwl_mvm *mvm,
                         u16 n_queued;
 
                         tid_data = &mvmsta->tid_data[tid];
-                        if (WARN(tid_data->state != IWL_AGG_ON &&
+                        if (WARN(!iwl_mvm_is_dqa_supported(mvm) &&
+                                 tid_data->state != IWL_AGG_ON &&
                                  tid_data->state != IWL_EMPTYING_HW_QUEUE_DELBA,
                                  "TID %d state is %d\n",
                                  tid, tid_data->state)) {
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/sta.h b/drivers/net/wireless/intel/iwlwifi/mvm/sta.h
index 4be34f902278..1927ce607798 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/sta.h
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/sta.h
@@ -547,7 +547,7 @@ void iwl_mvm_sta_modify_sleep_tx_count(struct iwl_mvm *mvm,
                                        struct ieee80211_sta *sta,
                                        enum ieee80211_frame_release_type reason,
                                        u16 cnt, u16 tids, bool more_data,
-                                       bool agg);
+                                       bool single_sta_queue);
 int iwl_mvm_drain_sta(struct iwl_mvm *mvm, struct iwl_mvm_sta *mvmsta,
                       bool drain);
 void iwl_mvm_sta_modify_disable_tx(struct iwl_mvm *mvm,
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
index dd2b4a300819..3f37075f4cde 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
@@ -7,7 +7,7 @@
  *
  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
- * Copyright(c) 2016        Intel Deutschland GmbH
+ * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of version 2 of the GNU General Public License as
@@ -34,6 +34,7 @@
  *
  * Copyright(c) 2012 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
+ * Copyright(c) 2016 - 2017 Intel Deutschland GmbH
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -628,8 +629,10 @@ int iwl_mvm_tx_skb_non_sta(struct iwl_mvm *mvm, struct sk_buff *skb)
          * values.
          * Note that we don't need to make sure it isn't agg'd, since we're
          * TXing non-sta
+         * For DQA mode - we shouldn't increase it though
          */
-        atomic_inc(&mvm->pending_frames[sta_id]);
+        if (!iwl_mvm_is_dqa_supported(mvm))
+                atomic_inc(&mvm->pending_frames[sta_id]);
 
         return 0;
 }
@@ -1005,11 +1008,8 @@ static int iwl_mvm_tx_mpdu(struct iwl_mvm *mvm, struct sk_buff *skb,
 
         spin_unlock(&mvmsta->lock);
 
-        /* Increase pending frames count if this isn't AMPDU */
-        if ((iwl_mvm_is_dqa_supported(mvm) &&
-             mvmsta->tid_data[tx_cmd->tid_tspec].state != IWL_AGG_ON &&
-             mvmsta->tid_data[tx_cmd->tid_tspec].state != IWL_AGG_STARTING) ||
-            (!iwl_mvm_is_dqa_supported(mvm) && !is_ampdu))
+        /* Increase pending frames count if this isn't AMPDU or DQA queue */
+        if (!iwl_mvm_is_dqa_supported(mvm) && !is_ampdu)
                 atomic_inc(&mvm->pending_frames[mvmsta->sta_id]);
 
         return 0;
@@ -1079,12 +1079,13 @@ static void iwl_mvm_check_ratid_empty(struct iwl_mvm *mvm,
         lockdep_assert_held(&mvmsta->lock);
 
         if ((tid_data->state == IWL_AGG_ON ||
-             tid_data->state == IWL_EMPTYING_HW_QUEUE_DELBA) &&
+             tid_data->state == IWL_EMPTYING_HW_QUEUE_DELBA ||
+             iwl_mvm_is_dqa_supported(mvm)) &&
             iwl_mvm_tid_queued(tid_data) == 0) {
                 /*
-                 * Now that this aggregation queue is empty tell mac80211 so it
-                 * knows we no longer have frames buffered for the station on
-                 * this TID (for the TIM bitmap calculation.)
+                 * Now that this aggregation or DQA queue is empty tell
+                 * mac80211 so it knows we no longer have frames buffered for
+                 * the station on this TID (for the TIM bitmap calculation.)
                  */
                 ieee80211_sta_set_buffered(sta, tid, false);
         }
@@ -1257,7 +1258,6 @@ static void iwl_mvm_rx_tx_cmd_single(struct iwl_mvm *mvm,
         u8 skb_freed = 0;
         u16 next_reclaimed, seq_ctl;
         bool is_ndp = false;
-        bool txq_agg = false; /* Is this TXQ aggregated */
 
         __skb_queue_head_init(&skbs);
 
@@ -1283,6 +1283,10 @@ static void iwl_mvm_rx_tx_cmd_single(struct iwl_mvm *mvm,
                         info->flags |= IEEE80211_TX_STAT_ACK;
                         break;
                 case TX_STATUS_FAIL_DEST_PS:
+                        /* In DQA, the FW should have stopped the queue and not
+                         * return this status
+                         */
+                        WARN_ON(iwl_mvm_is_dqa_supported(mvm));
                         info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
                         break;
                 default:
@@ -1387,15 +1391,6 @@ static void iwl_mvm_rx_tx_cmd_single(struct iwl_mvm *mvm,
                         bool send_eosp_ndp = false;
 
                         spin_lock_bh(&mvmsta->lock);
-                        if (iwl_mvm_is_dqa_supported(mvm)) {
-                                enum iwl_mvm_agg_state state;
-
-                                state = mvmsta->tid_data[tid].state;
-                                txq_agg = (state == IWL_AGG_ON ||
-                                        state == IWL_EMPTYING_HW_QUEUE_DELBA);
-                        } else {
-                                txq_agg = txq_id >= mvm->first_agg_queue;
-                        }
 
                         if (!is_ndp) {
                                 tid_data->next_reclaimed = next_reclaimed;
@@ -1452,11 +1447,11 @@ static void iwl_mvm_rx_tx_cmd_single(struct iwl_mvm *mvm,
          * If the txq is not an AMPDU queue, there is no chance we freed
          * several skbs. Check that out...
          */
-        if (txq_agg)
+        if (iwl_mvm_is_dqa_supported(mvm) || txq_id >= mvm->first_agg_queue)
                 goto out;
 
         /* We can't free more than one frame at once on a shared queue */
-        WARN_ON(!iwl_mvm_is_dqa_supported(mvm) && (skb_freed > 1));
+        WARN_ON(skb_freed > 1);
 
         /* If we have still frames for this STA nothing to do here */
         if (!atomic_sub_and_test(skb_freed, &mvm->pending_frames[sta_id]))