K 10
svn:author
V 6
adrian
K 8
svn:date
V 27
2011-09-19T08:01:21.373190Z
K 7
svn:log
V 1123
First cut at enabling the TX of BAR frams.

Currently ieee80211_send_bar() calls back into the driver
via ic->ic_raw_xmit(). The driver has some special case
code to directly dispatch BAR frames for this exact purpose.

This means that the hardware TXQ lock is needed, so BAR
frame TX must occur from _outside_ the TXQ lock.

* Unlock the TXQ before attempting to send a BAR frame
* Take a note of the txseq whilst inside the TXQ lock -
  although other contexts may allocate TX sequence numbers
  (and I'm about to stick that inside the TXQ lock too
  just to be safe), all frames from this point on have
  not yet attempted to be transmitted. So the TX sequence
  number at this point is fine as a left edge for the
  BAW.

This has only received light testing due to some bugs
I've introduced which make a fixed unicast rate no longer
work (the multi-rate retry schedule is incorrectly being
set.) This means that although I can trigger frame failure,
it isn't predictable or guaranteed. I'll fix that in a
subsequent commit and then properly test the aggregate
and non-aggregate BAR pathways whilst traffic is ongoing.

END