iwlwifi: mvm: add duplicate packet detection per rx queue

Next hardware will direct TCP/UDP streams to different cores.
Packets belonging to the same stream will be directed to the same
core.
The result is that duplicates will be always directed to the same
rx queue were the first packet was received.
This enabled parallelizing the duplicate packet detection across
the different cores, without sharing data between the rx queues.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

1 files changed, 66 insertions, 0 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c b/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c
index a9180b0..d891942 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/rxmq.c
@@ -285,6 +285,66 @@ static void iwl_mvm_rx_csum(struct ieee80211_sta *sta,
 		skb->ip_summed = CHECKSUM_UNNECESSARY;
 }
 
+/*
+ * returns true if a packet outside BA session is a duplicate and
+ * should be dropped
+ */
+static bool iwl_mvm_is_nonagg_dup(struct ieee80211_sta *sta, int queue,
+				  struct ieee80211_rx_status *rx_status,
+				  struct ieee80211_hdr *hdr,
+				  struct iwl_rx_mpdu_desc *desc)
+{
+	struct iwl_mvm_sta *mvm_sta;
+	struct iwl_mvm_rxq_dup_data *dup_data;
+	u8 baid, tid, sub_frame_idx;
+
+	if (WARN_ON(IS_ERR_OR_NULL(sta)))
+		return false;
+
+	baid = (le32_to_cpu(desc->reorder_data) &
+		IWL_RX_MPDU_REORDER_BAID_MASK) >>
+		IWL_RX_MPDU_REORDER_BAID_SHIFT;
+
+	if (baid != IWL_RX_REORDER_DATA_INVALID_BAID)
+		return false;
+
+	mvm_sta = iwl_mvm_sta_from_mac80211(sta);
+	dup_data = &mvm_sta->dup_data[queue];
+
+	/*
+	 * Drop duplicate 802.11 retransmissions
+	 * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
+	 */
+	if (ieee80211_is_ctl(hdr->frame_control) ||
+	    ieee80211_is_qos_nullfunc(hdr->frame_control) ||
+	    is_multicast_ether_addr(hdr->addr1)) {
+		rx_status->flag |= RX_FLAG_DUP_VALIDATED;
+		return false;
+	}
+
+	if (ieee80211_is_data_qos(hdr->frame_control))
+		/* frame has qos control */
+		tid = *ieee80211_get_qos_ctl(hdr) &
+			IEEE80211_QOS_CTL_TID_MASK;
+	else
+		tid = IWL_MAX_TID_COUNT;
+
+	/* If this wasn't a part of an A-MSDU the sub-frame index will be 0 */
+	sub_frame_idx = desc->amsdu_info & IWL_RX_MPDU_AMSDU_SUBFRAME_IDX_MASK;
+
+	if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
+		     dup_data->last_seq[tid] == hdr->seq_ctrl &&
+		     dup_data->last_sub_frame[tid] >= sub_frame_idx))
+		return true;
+
+	dup_data->last_seq[tid] = hdr->seq_ctrl;
+	dup_data->last_sub_frame[tid] = sub_frame_idx;
+
+	rx_status->flag |= RX_FLAG_DUP_VALIDATED;
+
+	return false;
+}
+
 void iwl_mvm_rx_mpdu_mq(struct iwl_mvm *mvm, struct napi_struct *napi,
 			struct iwl_rx_cmd_buffer *rxb, int queue)
 {
@@ -389,6 +449,12 @@ void iwl_mvm_rx_mpdu_mq(struct iwl_mvm *mvm, struct napi_struct *napi,
 
 		if (ieee80211_is_data(hdr->frame_control))
 			iwl_mvm_rx_csum(sta, skb, desc);
+
+		if (iwl_mvm_is_nonagg_dup(sta, queue, rx_status, hdr, desc)) {
+			kfree_skb(skb);
+			rcu_read_unlock();
+			return;
+		}
 	}
 
 	/*