mac80211: RX BA support for sta max_rx_aggregation_subframes

commit 480dd46b9d6812e5fb7172c305ee0f1154c26eed upstream.

The ability to change the max_rx_aggregation frames is useful
in cases of IOP.

There exist some devices (latest mobile phones and some AP's)
that tend to not respect a BA sessions maximum size (in Kbps).
These devices won't respect the AMPDU size that was negotiated during
association (even though they do respect the maximal number of packets).

This violation is characterized by a valid number of packets in
a single AMPDU. Even so, the total size will exceed the size negotiated
during association.

Eventually, this will cause some undefined behavior, which in turn
causes the hw to drop packets, causing the throughput to plummet.

This patch will make the subframe limitation to be held by each station,
instead of being held only by hw.

Signed-off-by: Maxim Altshul <maxim.altshul@ti.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index ebd73169d53beea7050d3a122da2032b1bb65cca..4e51f9a5a177940cd711694ec80a5232693a6995 100644 (file)
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -1662,6 +1662,9 @@ struct ieee80211_sta_rates {
  * @supp_rates: Bitmap of supported rates (per band)
  * @ht_cap: HT capabilities of this STA; restricted to our own capabilities
  * @vht_cap: VHT capabilities of this STA; restricted to our own capabilities
+ * @max_rx_aggregation_subframes: maximal amount of frames in a single AMPDU
+ *     that this station is allowed to transmit to us.
+ *     Can be modified by driver.
  * @wme: indicates whether the STA supports QoS/WME (if local devices does,
  *     otherwise always false)
  * @drv_priv: data area for driver use, will always be aligned to
@@ -1688,6 +1691,7 @@ struct ieee80211_sta {
        u16 aid;
        struct ieee80211_sta_ht_cap ht_cap;
        struct ieee80211_sta_vht_cap vht_cap;
+       u8 max_rx_aggregation_subframes;
        bool wme;
        u8 uapsd_queues;
        u8 max_sp;

diff --git a/net/mac80211/agg-rx.c b/net/mac80211/agg-rx.c
index f598ff80b30e129487ee7d25012ef6c5602599db..a830356b94acffeb2ff9c6bfced612ccd9aa5176 100644 (file)
--- a/net/mac80211/agg-rx.c
+++ b/net/mac80211/agg-rx.c
@@ -290,10 +290,13 @@ void __ieee80211_start_rx_ba_session(struct sta_info *sta,
                buf_size = IEEE80211_MAX_AMPDU_BUF;
 
        /* make sure the size doesn't exceed the maximum supported by the hw */
-       if (buf_size > local->hw.max_rx_aggregation_subframes)
-               buf_size = local->hw.max_rx_aggregation_subframes;
+       if (buf_size > sta->sta.max_rx_aggregation_subframes)
+               buf_size = sta->sta.max_rx_aggregation_subframes;
        params.buf_size = buf_size;
 
+       ht_dbg(sta->sdata, "AddBA Req buf_size=%d for %pM\n",
+              buf_size, sta->sta.addr);
+
        /* examine state machine */
        mutex_lock(&sta->ampdu_mlme.mtx);
 

diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 67066d048e6fb00033a660e7bbaad11d5621b1ac..63ea6cbac5add6a9e5f58722f0b748b2a8cb0e26 100644 (file)
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -329,6 +329,9 @@ struct sta_info *sta_info_alloc(struct ieee80211_sub_if_data *sdata,
 
        memcpy(sta->addr, addr, ETH_ALEN);
        memcpy(sta->sta.addr, addr, ETH_ALEN);
+       sta->sta.max_rx_aggregation_subframes =
+               local->hw.max_rx_aggregation_subframes;
+
        sta->local = local;
        sta->sdata = sdata;
        sta->rx_stats.last_rx = jiffies;