When a packet is supposed to sent be as an a-MPDU, mac80211 sets
IEEE80211_TX_CTL_AMPDU to let the driver know. On the other
hand, mac80211 configures the driver for aggregration with the
ampdu_action callback.
There is race between these two mechanisms since the following
scenario can occur when the BA agreement is torn down:
Tx softIRQ drv configuration
========== =================
check OPERATIONAL bit
Set the TX_CTL_AMPDU bit in the packet
clear OPERATIONAL bit
stop Tx AGG
Pass Tx packet to the driver.
In that case the driver would get a packet with TX_CTL_AMPDU set
although it has already been notified that the BA session has been
torn down.
To fix this, we need to synchronize all the Qdisc activity after we
cleared the OPERATIONAL bit. After that step, all the following
packets will be buffered until the driver reports it is ready to get
new packets for this RA / TID. This buffering allows not to run into
another race that would send packets with TX_CTL_AMPDU unset while
the driver hasn't been requested to tear down the BA session yet.
This race occurs in practice and iwlwifi complains with a WARN_ON
when it happens.
Cc: stable@kernel.org
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
If addBA responses comes in just after addba_resp_timer has
expired mac80211 will still accept it and try to open the
aggregation session. This causes drivers to be confused and
in some cases even crash.
This patch fixes the race condition and makes sure that if
addba_resp_timer has expired addBA response is not longer
accepted and we do not try to open half-closed session.
Cc: stable@vger.kernel.org
Signed-off-by: Nikolay Martynov <mar.kolya@gmail.com>
[some adjustments]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Nikolay noticed (by code review) that mac80211 can
attempt to stop an aggregation session while it is
already being stopped. So to fix it, check whether
stop is already being done and bail out if so.
Also move setting the STOPPING state into the lock
so things are properly atomic.
Cc: stable@vger.kernel.org
Reported-by: Nikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Sparse RCU checking reports two warnings in the mesh
path table code. These are due to questionable uses of
rcu_dereference.
To fix the first one, get rid of mesh_gate_add() and
just make mesh_path_add_gate() do the correct deref.
To fix the second one, simply remove rcu_dereference()
in mesh_gate_del() -- it already gets a proper pointer
as indicated by the prototype (no __rcu annotation)
and confirmed by the code.
Cc: Javier Cardona <javier@cozybit.com>
Cc: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This implements ht-cap over-rides for mac80211 drivers.
HT may be disabled, making an /a/b/g/n station act like an
a/b/g station. HT40 may be disabled forcing the station to
be HT20 even if the AP and local hardware support HT40.
MAX-AMSDU may be disabled.
AMPDU-Density may be increased.
AMPDU-Factor may be decreased.
This has been successfully tested with ath9k using patched
wpa_supplicant and iw.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
No other driver ever ended up using this, and
the commit forgot to move the prototype so no
driver could have used it. Revert it, if any
driver shows up and needs it it can be moved
again, but until then it's more efficient to
have it in mac80211 where the only user is.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Currently mac80211 implements these for all devices,
but given restrictions of some devices that isn't
really true, so prepare for being able to remove the
capability for some mac80211 devices.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Kalle Valo <kvalo@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
First time I tried smatch, and it says:
mesh_hwmp.c +870 mesh_queue_preq(21) error: double lock 'bottom_half:'
mesh_hwmp.c +873 mesh_queue_preq(24) error: double unlock 'bottom_half:'
mesh_hwmp.c +886 mesh_queue_preq(37) error: double unlock 'bottom_half:'
Which is indeed true -- there's no point in disabling BHs
again if we just did that a few lines earlier, so remove.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
WLAN_STA_ASSOC_AP indicates that the station entry
is for an AP we're associated to but isn't used so
remove it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Drivers can usually handle fragmented packets
much easier when they get the entire list of
fragments at once. The only thing they need to
do is keep enough space on the queues for up
to ten fragments of a single MSDU.
This allows them to implement this with a new
operation tx_frags.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This just prepares for passing the entire fragment
list to the driver. No significant changes, but the
TX throughput is calculated slightly differently
now and we blink only once for each MSDU.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Instead of adjusting the fragment flags at
TX time, adjust them at fragmentation time.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
We are currently linking the skbs by using skb->next
directly. This works, but the preferred way is to use
a struct sk_buff_head instead. That also prepares for
passing that to drivers directly.
While at it I noticed we calculate the duration for
fragments twice -- remove one of them.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The forcedeth changes had a conflict with the conversion over
to atomic u64 statistics in net-next.
The libertas cfg.c code had a conflict with the bss reference
counting fix by John Linville in net-next.
Conflicts:
drivers/net/ethernet/nvidia/forcedeth.c
drivers/net/wireless/libertas/cfg.c
Some drivers (e.g. ath9k) assume that it's safe to go into low-power mode
immediately after the idle state changes. To support that, mac80211 even
calls drv_flush() before that happens.
In some instances, mac80211 sent a packet right after recalculating the
idle state, this patch fixes that.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Remove unused function parameters in the following functions:
minstrel_calc_rate_ewma()
minstrel_ht_calc_tp()
minstrel_aggr_check()
minstrel_ht_set_rate()
Signed-off-by: Patrick Kelle <patrick.kelle81@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
David S. Miller
John W. Linville
Emmanuel Grumbach
Nikolay Martynov
Johannes Berg
Ben Greear
Helmut Schaa
Felix Fietkau
Patrick Kelle
Dan Carpenter