Enable driver to manage the reordering logic itself.
This is needed for example for the iwlwifi driver that
will support hardware assisted reordering.
Signed-off-by: NSara Sharon <sara.sharon@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Currently mac80211 does not inform the driver of the session
block ack timeout when starting a rx aggregation session.
Drivers that manage the reorder buffer need to know this
parameter.
Seeing that there are now too many arguments for the
drv_ampdu_action() function, wrap them inside a structure.
Signed-off-by: NSara Sharon <sara.sharon@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Currently mac80211 does not inform the driver of the window
size when starting an RX aggregation session.
To enable managing the reorder buffer in the driver or hardware
the window size is needed.
Signed-off-by: NSara Sharon <sara.sharon@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Drivers may be interested in receiving A-MSDU within A-MDPU.
Not all the devices may be able to do so, make it configurable.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Advertise the capability to send A-MSDU within A-MPDU
in the AddBA request sent by mac80211. Let the driver
know about the peer's capabilities.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There's an issue with the way the RX A-MPDU reorder timer is
deleted that can cause a kernel crash like this:

 * tid_rx is removed - call_rcu(ieee80211_free_tid_rx)
 * station is destroyed
 * reorder timer fires before ieee80211_free_tid_rx() runs,
   accessing the station, thus potentially crashing due to
   the use-after-free

The station deletion is protected by synchronize_net(), but
that isn't enough -- ieee80211_free_tid_rx() need not have
run when that returns (it deletes the timer.) We could use
rcu_barrier() instead of synchronize_net(), but that's much
more expensive.

Instead, to fix this, add a field tracking that the session
is being deleted. In this case, the only re-arming of the
timer happens with the reorder spinlock held, so make that
code not rearm it if the session is being deleted and also
delete the timer after setting that field. This ensures the
timer cannot fire after ___ieee80211_stop_rx_ba_session()
returns, which fixes the problem.

Cc: stable@vger.kernel.org
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If a peer or some local agent (rate control, ...) decides to start
an aggregation session but doesn't support HT (which also implies
QoS), reject it.

This is mostly a corner case as such peers normally won't try to
use block-ack sessions and rate control wouldn't start them, but
technically QoS stations could request it according to the spec.

However, since drivers don't really support such non-HT sessions
it's better to reject them.

Also, while at it, move the tracing for TX sessions earlier so it
captures the error cases as well.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When starting an offloaded BA session it is
unknown what starting sequence number should be
used. Using last_seq worked in most cases except
after hw restart.

When hw restart is requested last_seq is
(rightfully so) kept unmodified. This ended up
with BA sessions being restarted with an aribtrary
BA window values resulting in dropped frames until
sequence numbers caught up.

Instead of last_seq pick seqno of a first Rxed
frame of a given BA session.

This fixes stalled traffic after hw restart with
offloaded BA sessions (currently only ath10k).
Signed-off-by: NMichal Kazior <michal.kazior@tieto.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Some drivers may be performing most of Tx/Rx
aggregation on their own (e.g. in firmware)
including AddBa/DelBa negotiations but may
otherwise require Rx reordering assistance.

The patch exports 2 new functions for establishing
Rx aggregation sessions in assumption device
driver has taken care of the necessary
negotiations.
Signed-off-by: NMichal Kazior <michal.kazior@tieto.com>
[fix endian bug]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Some drivers (e.g. ath10k) report A-MSDU subframes
individually with identical seqno. The A-MPDU Rx
reorder code did not account for that which made
it practically unusable with drivers using
RX_FLAG_AMSDU_MORE because it would end up
dropping a lot of frames resulting in confusion in
upper network transport layers.
Signed-off-by: NMichal Kazior <michal.kazior@tieto.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

A lot of the aggregation messages don't indicate the
station so they're hard to understand if there are
multiple sessions in progress. Make that easier by
adding the MAC address to most messages. Also add
the TID if it wasn't already there.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Introduce IEEE80211_NUM_TIDS in the generic 802.11
header file and use it in place of STA_TID_NUM and
NUM_RX_DATA_QUEUES which are both really the number
of TIDs.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There are a few things that make the logging and
debugging in mac80211 less useful than it should
be right now:
 * a lot of messages should be pr_info, not pr_debug
 * wholesale use of pr_debug makes it require *both*
   Kconfig and dynamic configuration
 * there are still a lot of ifdefs
 * the style is very inconsistent, sometimes the
   sdata->name is printed in front

Clean up everything, introducing new macros and
separating out the station MLME debugging into
a new Kconfig symbol.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Simplify the use of #ifdef CONFIG_MAC80211_HT_DEBUG/#endif
by adding a logging macro to encapsulate the test.

Convert the appropriate uses too.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Standardize the debugging to be able to use dynamic_debug.

Coalesce formats, align arguments.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fixes a lockdep warning:

===================================================
[ INFO: suspicious rcu_dereference_check() usage. ]
---------------------------------------------------
net/mac80211/agg-rx.c:148 invoked rcu_dereference_check() without protection!

other info that might help us debug this:

rcu_scheduler_active = 1, debug_locks = 1
1 lock held by arecord/11226:
 #0:  (&tid_agg_rx->session_timer){+.-...}, at: [<ffffffff81066bb0>] call_timer_fn+0x0/0x360

stack backtrace:
Pid: 11226, comm: arecord Not tainted 3.1.0-kml #16
Call Trace:
 <IRQ>  [<ffffffff81093454>] lockdep_rcu_dereference+0xa4/0xc0
 [<ffffffffa02778c9>] sta_rx_agg_session_timer_expired+0xc9/0x110 [mac80211]
 [<ffffffffa0277800>] ? ieee80211_process_addba_resp+0x220/0x220 [mac80211]
 [<ffffffff81066c3a>] call_timer_fn+0x8a/0x360
 [<ffffffff81066bb0>] ? init_timer_deferrable_key+0x30/0x30
 [<ffffffff81477bb0>] ? _raw_spin_unlock_irq+0x30/0x70
 [<ffffffff81067049>] run_timer_softirq+0x139/0x310
 [<ffffffff81091d5e>] ? put_lock_stats.isra.25+0xe/0x40
 [<ffffffff810922ac>] ? lock_release_holdtime.part.26+0xdc/0x160
 [<ffffffffa0277800>] ? ieee80211_process_addba_resp+0x220/0x220 [mac80211]
 [<ffffffff8105cb78>] __do_softirq+0xc8/0x3c0
 [<ffffffff8108f088>] ? tick_dev_program_event+0x48/0x110
 [<ffffffff8108f16f>] ? tick_program_event+0x1f/0x30
 [<ffffffff81153b15>] ? putname+0x35/0x50
 [<ffffffff8147a43c>] call_softirq+0x1c/0x30
 [<ffffffff81004c55>] do_softirq+0xa5/0xe0
 [<ffffffff8105d1ee>] irq_exit+0xae/0xe0
 [<ffffffff8147ac6b>] smp_apic_timer_interrupt+0x6b/0x98
 [<ffffffff81479ab3>] apic_timer_interrupt+0x73/0x80
 <EOI>  [<ffffffff8146aac6>] ? free_debug_processing+0x1a1/0x1d5
 [<ffffffff81153b15>] ? putname+0x35/0x50
 [<ffffffff8146ab2b>] __slab_free+0x31/0x2ca
 [<ffffffff81477c3a>] ? _raw_spin_unlock_irqrestore+0x4a/0x90
 [<ffffffff81253b8f>] ? __debug_check_no_obj_freed+0x15f/0x210
 [<ffffffff81097054>] ? lock_release_nested+0x84/0xc0
 [<ffffffff8113ec55>] ? kmem_cache_free+0x105/0x250
 [<ffffffff81153b15>] ? putname+0x35/0x50
 [<ffffffff81153b15>] ? putname+0x35/0x50
 [<ffffffff8113ed8f>] kmem_cache_free+0x23f/0x250
 [<ffffffff81153b15>] putname+0x35/0x50
 [<ffffffff81146d8d>] do_sys_open+0x16d/0x1d0
 [<ffffffff81146e10>] sys_open+0x20/0x30
 [<ffffffff81478f42>] system_call_fastpath+0x16/0x1b
Reported-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Standardize the net core ratelimited logging functions.

Coalesce formats, align arguments.
Change a printk then vprintk sequence to use printf extension %pV.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Calling mod_timer from the rx/tx hotpath is somewhat expensive, and the
timeout doesn't need to be so precise.

Switch to a different strategy: Schedule the timer initially, store jiffies
of all last rx/tx activity which would previously modify the timer, and
let the timer re-arm itself after checking the last rx/tx timestamp.
Make the session timers deferrable to avoid causing extra wakeups on systems
running on battery.
This visibly reduces CPU load under high network load on small embedded
systems.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Is possible that we will arm the tid_rx->reorder_timer after
del_timer_sync() in ___ieee80211_stop_rx_ba_session(). We need to stop
timer after RCU grace period finish, so move it to
ieee80211_free_tid_rx(). Timer will not be armed again, as
rcu_dereference(sta->ampdu_mlme.tid_rx[tid]) will return NULL.

Debug object detected problem with the following warning:
ODEBUG: free active (active state 0) object type: timer_list hint: sta_rx_agg_reorder_timer_expired+0x0/0xf0 [mac80211]

Bug report (with all warning messages):
https://bugzilla.redhat.com/show_bug.cgi?id=804007Reported-by: N"jan p. springer" <jsd@igroup.org>
Cc: stable@vger.kernel.org
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

commit a9b3cd7f (rcu: convert uses of rcu_assign_pointer(x, NULL) to
RCU_INIT_POINTER) did a lot of incorrect changes, since it did a
complete conversion of rcu_assign_pointer(x, y) to RCU_INIT_POINTER(x,
y).

We miss needed barriers, even on x86, when y is not NULL.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

The HT mode is set by iw (previous patchsets).
The interface is set into the specified HT mode.
HT mode and capabilities are announced in beacons.

If we add a station that uses HT also, the fastest matching HT mode will
be used for transmission. That means if we are using HT40+ and we add a station
running on HT40-, we would transfer at HT20.

If we join an IBSS with HT40, but the secondary channel is not
available, we will fall back into HT20 as well.

Allow frame aggregation to start in IBSS mode.
Signed-off-by: NAlexander Simon <an.alexsimon@googlemail.com>
[siwu@hrz.tu-chemnitz.de: Updates]
* remove implicit channel_type enum assumptions
* use rate_control_rate_init() if channel type changed
* remove channel flags check
* activate HT IBSS feature support
* slightly reword commit message
* rebase on wireless-testing
Signed-off-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NMathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Reviewed-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This fixes frequent WARN_ONs when using AP VLAN + aggregation, as these vifs
are virtual and not registered with drivers.
Use sta_info_get_bss instead of sta_info_get in aggregation callbacks, so
that these callbacks can find the station entry when called with the AP vif.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

  Add additional debug logging of initiator and reason when rx
aggregation session is stopped
Signed-off-by: NNikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

  Use WLAN_BACK_RECIPIENT instead of hardcoded 0 for clarity
Signed-off-by: NNikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NAshok Nagarajan <anagar6@uic.edu>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

The flaglock in struct sta_info has long been
something that I wanted to get rid of, this
finally does the conversion to atomic bitops.

The conversion itself is straight-forward in
most places, a few things needed to change a
bit since we can no longer use multiple bits
at the same time.

On x86-64, this is a fairly significant code
size reduction:
   text	   data	    bss	    dec	    hex
 427861	  23648	   1008	 452517	  6e7a5	before
 425383	  23648	    976	 450007	  6ddd7	after
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Removing unnecessary messages saves code and text.

Site specific OOM messages are duplications of a generic MM
out of memory message and aren't really useful, so just
delete them.
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When assigning a NULL value to an RCU protected pointer, no barrier
is needed. The rcu_assign_pointer, used to handle that but will soon
change to not handle the special case.

Convert all rcu_assign_pointer of NULL value.

//smpl
@@ expression P; @@

- rcu_assign_pointer(P, NULL)
+ RCU_INIT_POINTER(P, NULL)

// </smpl>
Signed-off-by: NStephen Hemminger <shemminger@vyatta.com>
Acked-by: NPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

ieee80211_stop_rx_ba_session() was calling sta_info_get()
without rcu locking, and the return value was not
checked.
This resulted in the following panic:

[<bf05726c>] (ieee80211_stop_rx_ba_session+0x0/0x60 [mac80211])
[<bf0abd94>] (wl1271_event_handle+0x0/0xdc8 [wl12xx])
[<bf0a7308>] (wl1271_irq+0x0/0x4a0 [wl12xx])
[<c00c40a8>] (irq_thread+0x0/0x254)
[<c00a7398>] (kthread+0x0/0x8c)
Signed-off-by: NEliad Peller <eliad@wizery.com>
Reviewed-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When forming a Rx BA session, sometimes the ADDBA response gets lost.
This leads to a situation where the session is configured locally, but
doesn't exist on the remote side. Subsequent ADDBA requests are declined
by mac80211.

Fix this by assuming the session state of the initiator is the correct
one. When receiving an unexpected ADDBA request on a TID with an active
Rx BA session, delete the existing one and establish a new session.
Signed-off-by: NArik Nemtsov <arik@wizery.com>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some devices support BT/WLAN co-existence algorigthms.
In order not to harm the system performance and user experience, the device
requests not to allow any RX BA session and tear down existing RX BA sessions
based on system constraints such as periodic BT activity that needs to limit
WLAN activity (eg.SCO or A2DP).
In such cases, the intention is to limit the duration of the RX PPDU and
therefore prevent the peer device to use A-MPDU aggregation.

Adding ieee80211_stop_rx_ba_session() callback
that can be used by the driver to stop existing BA sessions.
Signed-off-by: NShahar Levi <shahar_levi@ti.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This adds sparse RCU annotations to most of
mac80211, only the mesh code remains to be
done.

Due the the previous patches, the annotations
are pretty simple. The only thing that this
actually changes is removing the RCU usage of
key->sta in debugfs since this pointer isn't
actually an RCU-managed pointer (it only has
a single assignment done before the key even
goes live). As that is otherwise harmless, I
decided to make it part of this patch.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The aggregation code currently doesn't implement the
buffer size negotiation. It will always request a max
buffer size (which is fine, if a little pointless, as
the mac80211 code doesn't know and might just use 0
instead), but if the peer requests a smaller size it
isn't possible to honour this request.

In order to fix this, look at the buffer size in the
addBA response frame, keep track of it and pass it to
the driver in the ampdu_action callback when called
with the IEEE80211_AMPDU_TX_OPERATIONAL action. That
way the driver can limit the number of subframes in
aggregates appropriately.

Note that this doesn't fix any drivers apart from the
addition of the new argument -- they all need to be
updated separately to use this variable!
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some devices don't support the maximum AMDPU buffer size of 64, so we
need to add an option to configure this in the hardware configuration.
This value will be used in the ADDBA response instead of the value
suggested in the request, if the latter is greater than the max
supported.
Signed-off-by: NLuciano Coelho <coelho@ti.com>
Tested-by: NJuuso Oikarinen <juuso.oikarinen@nokia.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the buffer size is set to zero in the block ack parameter set
field, we should use the maximum supported number of subframes.  The
existing code was bogus and was doing some unnecessary calculations
that lead to wrong values.

Thanks Johannes for helping me figure this one out.

Cc: stable@kernel.org
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: NLuciano Coelho <coelho@ti.com>
Reviewed-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The RX aggregation locking documentation was
wrong, which led Christian to also code the
timer timeout handling for it somewhat wrongly.

Fix the documentation, the two places that
need to hold the reorder lock across accesses
to the structure, and the debugfs code that
should just use RCU.

Also, remove acquiring the sta->lock across
reorder timeouts since it isn't necessary, and
change a few places to GFP_KERNEL because the
code path here doesn't need atomic allocations
as I noticed when reviewing all this.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Acked-by: NChristian Lamparter <chunkeey@googlemail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When roaming while we have active BA session,
we can end up transmitting delBA frames to
the old AP while we're already on the new AP's
channel, which can cause warnings.

Simply avoid sending those frames, but still
tear down the internal session state, since
they are not really necessary anyway as we
will implicitly disassociate when sending the
association to the new AP.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Acked-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch introduces a new timer, which will release
queued-up MPDUs from the reorder buffer, whenever
they've waited for more than HT_RX_REORDER_BUF_TIMEOUT
(which is at around 100 ms).

The advantage of having a dedicated timer, instead of
relying on a constant stream of freshly arriving aMPDUs
to release the old ones, is particularly observable when
even a small fraction of MPDUs are forever lost at
low network speeds.

Previously under these circumstances frames would become
stuck in the reorder buffer and the network stack of both
HT peers throttled back, instead of revving up and
gunning the pipes.
Signed-off-by: NChristian Lamparter <chunkeey@googlemail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Even before the recent changes, the documentation
for TX aggregation was somewhat out of date. Update
it and also add documentation for the RX side.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>