mac80211: dont allow fragmentation and requeuing on A-MPDU queues

There really is no reason for a driver to reject a frame on
an A-MPDU queue when it can stop that queue for any period
of time and is given frames one by one. Hence, disallow it
with a big warning and reduce mac80211-internal state.

Also add a warning when we try to fragment a frame destined
for an A-MPDU queue and drop it, the actual bug needs to be
fixed elsewhere but I'm not exactly sure how to yet.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Ron Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 54960b83db79..4df39eb9115f 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -986,8 +986,10 @@ enum ieee80211_ampdu_mlme_action {
  * @tx: Handler that 802.11 module calls for each transmitted frame.
  *      skb contains the buffer starting from the IEEE 802.11 header.
  *      The low-level driver should send the frame out based on
- *      configuration in the TX control data. Must be implemented and
- *      atomic.
+ *      configuration in the TX control data. This handler should,
+ *      preferably, never fail and stop queues appropriately, more
+ *      importantly, however, it must never fail for A-MPDU-queues.
+ *      Must be implemented and atomic.
  *
  * @start: Called before the first netdevice attached to the hardware
  *      is enabled. This should turn on the hardware and must turn on