mac80211: refactor duplicate detection

Put duplicate detection into its own RX handler, and separate
out the conditions a bit to make the code more readable.

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

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index f57af5c..0f4297e 100644 (file)
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -1047,7 +1047,7 @@ static void ieee80211_rx_reorder_ampdu(struct ieee80211_rx_data *rx,
 }
 
 static ieee80211_rx_result debug_noinline
-ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
+ieee80211_rx_h_check_dup(struct ieee80211_rx_data *rx)
 {
        struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
        struct ieee80211_rx_status *status = IEEE80211_SKB_RXCB(rx->skb);
@@ -1056,10 +1056,16 @@ ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
         * Drop duplicate 802.11 retransmissions
         * (IEEE 802.11-2012: 9.3.2.10 "Duplicate detection and recovery")
         */
-       if (rx->skb->len >= 24 && rx->sta &&
-           !ieee80211_is_ctl(hdr->frame_control) &&
-           !ieee80211_is_qos_nullfunc(hdr->frame_control) &&
-           !is_multicast_ether_addr(hdr->addr1)) {
+
+       if (rx->skb->len < 24)
+               return RX_CONTINUE;
+
+       if (ieee80211_is_ctl(hdr->frame_control) ||
+           ieee80211_is_qos_nullfunc(hdr->frame_control) ||
+           is_multicast_ether_addr(hdr->addr1))
+               return RX_CONTINUE;
+
+       if (rx->sta) {
                if (unlikely(ieee80211_has_retry(hdr->frame_control) &&
                             rx->sta->last_seq_ctrl[rx->seqno_idx] ==
                             hdr->seq_ctrl)) {
@@ -1073,6 +1079,14 @@ ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
                }
        }
 
+       return RX_CONTINUE;
+}
+
+static ieee80211_rx_result debug_noinline
+ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
+{
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)rx->skb->data;
+
        if (unlikely(rx->skb->len < 16)) {
                I802_DEBUG_INC(rx->local->rx_handlers_drop_short);
                return RX_DROP_MONITOR;
@@ -3110,6 +3124,7 @@ static void ieee80211_invoke_rx_handlers(struct ieee80211_rx_data *rx)
                        goto rxh_next;  \
        } while (0);
 
+       CALL_RXH(ieee80211_rx_h_check_dup)
        CALL_RXH(ieee80211_rx_h_check)
 
        ieee80211_rx_reorder_ampdu(rx, &reorder_release);