iwlwifi: mvm: add reorder timeout per frame

Add a timer in order to release expired frames from the
reorder buffer.
This is needed since some APs do not retransmit frames
to fill in the reorder holes and in TCP it results with
a complete stall of traffic.

This has a few side effects on the general design:

The nssn may not reflect the the head of the reorder buffer.
This situation is valid, and packets with SN lower than the
reorder buffer head will be dropped.

Another side effect is that since the reorder timer might expire
we need to lock the reorder buffer.
This however is fine since the locking is only inside a
single reorder buffer between RX path and reorder timeout and
there is no outside contention.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

1 files changed, 12 insertions, 0 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h b/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
index 8272e54832b4..3c331bdadff7 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mvm.h
@@ -623,6 +623,12 @@ struct iwl_mvm_shared_mem_cfg {
  * @last_amsdu: track last ASMDU SN for duplication detection
  * @last_sub_index: track ASMDU sub frame index for duplication detection
  * @entries: list of skbs stored
+ * @reorder_time: time the packet was stored in the reorder buffer
+ * @reorder_timer: timer for frames are in the reorder buffer. For AMSDU
+ *	it is the time of last received sub-frame
+ * @removed: prevent timer re-arming
+ * @lock: protect reorder buffer internal state
+ * @mvm: mvm pointer, needed for frame timer context
  */
 struct iwl_mvm_reorder_buffer {
 	u16 head_sn;
@@ -633,6 +639,11 @@ struct iwl_mvm_reorder_buffer {
 	u16 last_amsdu;
 	u8 last_sub_index;
 	struct sk_buff_head entries[IEEE80211_MAX_AMPDU_BUF];
+	unsigned long reorder_time[IEEE80211_MAX_AMPDU_BUF];
+	struct timer_list reorder_timer;
+	bool removed;
+	spinlock_t lock;
+	struct iwl_mvm *mvm;
 } ____cacheline_aligned_in_smp;
 
 /**
@@ -1682,6 +1693,7 @@ void iwl_mvm_tdls_ch_switch_work(struct work_struct *work);
 void iwl_mvm_sync_rx_queues_internal(struct iwl_mvm *mvm,
 				     struct iwl_mvm_internal_rxq_notif *notif,
 				     u32 size);
+void iwl_mvm_reorder_timer_expired(unsigned long data);
 struct ieee80211_vif *iwl_mvm_get_bss_vif(struct iwl_mvm *mvm);
 
 void iwl_mvm_nic_restart(struct iwl_mvm *mvm, bool fw_error);