Currently, the tx queue were selected implicitly in ndo_dfwd_start_xmit(). The
will cause several issues:

- NETIF_F_LLTX were removed for macvlan, so txq lock were done for macvlan
  instead of lower device which misses the necessary txq synchronization for
  lower device such as txq stopping or frozen required by dev watchdog or
  control path.
- dev_hard_start_xmit() was called with NULL txq which bypasses the net device
  watchdog.
- dev_hard_start_xmit() does not check txq everywhere which will lead a crash
  when tso is disabled for lower device.

Fix this by explicitly introducing a new param for .ndo_select_queue() for just
selecting queues in the case of l2 forwarding offload. netdev_pick_tx() was also
extended to accept this parameter and dev_queue_xmit_accel() was used to do l2
forwarding transmission.

With this fixes, NETIF_F_LLTX could be preserved for macvlan and there's no need
to check txq against NULL in dev_hard_start_xmit(). Also there's no need to keep
a dedicated ndo_dfwd_start_xmit() and we can just reuse the code of
dev_queue_xmit() to do the transmission.

In the future, it was also required for macvtap l2 forwarding support since it
provides a necessary synchronization method.

Cc: John Fastabend <john.r.fastabend@intel.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: e1000-devel@lists.sourceforge.net
Signed-off-by: Jason Wang <jasowang@redhat.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Conflicts:
	net/ieee802154/6lowpan.c

If a uAPSD service period ends with an MMPDU, we currently just
send that MMPDU, but it obviously won't get the EOSP bit set as
it doesn't have a QoS header. This contradicts the standard, so
add a QoS-nulldata frame after the MMPDU to properly terminate
the service period with a frame that has EOSP set.

Also fix a bug wrt. the TID for the MMPDU, it shouldn't be set
to 0 unconditionally but use the actual TID that was assigned.

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

The temporary TX info flags need to be cleared if the frame will
be processed through the TX handlers again, otherwise it can get
messed up. This fixes a bug that happened when an aggregation
session was stopped while the station was sleeping - some frames
might get transmitted marked as aggregation erroneously without
this fix.

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

When a response for PS-Poll or a uAPSD trigger frame is sent, the
more-data bit should be set according to 802.11-2012 11.2.1.5 h),
meaning that it should indicate more data on the relevant ACs
(delivery-enabled or nondelivery-enabled for uAPSD or PS-Poll.)

In, for example, the following scenario:
 * 1 frame on VO queue (either in driver or in mac80211)
 * at least 1 frame on VI queue (in the driver)
 * both VO/VI are delivery-enabled
 * uAPSD trigger frame received

The more-data flag to the driver would not be set, even though
it should be.

While fixing this, I noticed that we should really release frames
from multiple ACs where there's data buffered in the driver for
the corresponding TIDs.

To address all this, restructure the code a bit to consider all
ACs if we only release driver frames or only buffered frames.
This also addresses the more-data bug described above as now the
TIDs will all be marked as released, so the driver will have to
check the number of frames.

While at it, clarify some code and comments and remove the found
variable, replacing it with the appropriate sw/hw release check.

Reported-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Using ffs() for the PS-Poll release TID is wrong, it will cause
frames to be released in order 0 1 2 3 4 5 6 7 instead of the
correct 7 6 5 4 3 0 2 1. Fix this by adding a new function that
implements "highest priority TID" properly.

Reported-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In managed mode, we should not ask for OFF mode because the
power settings may still require DYNAMIC. In AP mode, this
should be allowed since the default settings is OFF and
AUTOMATIC is not allowed.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Using an int with 0/1 is not very common, make the function
return a bool instead with the same values (false/true).

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