Commit Graph

96 Commits

Author SHA1 Message Date
Chaitanya 50c16e2251 mac80211: warn only once if ampdu_action isn't assigned
New drivers that might not support ampdu_action yet while in
development cause a lot of warnings, use WARN_ON_ONCE instead.

Signed-off-by: T Krushna Chaitanya <chaitanyatk@posedge.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-12-07 09:12:50 +01:00
Johannes Berg 5a306f5887 mac80211: introduce IEEE80211_NUM_TIDS and use it
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: Johannes Berg <johannes.berg@intel.com>
2012-11-19 15:44:00 +01:00
Johannes Berg c6f219dc83 mac80211: don't send delBA on addBA failure
There's no reason to send a delBA when the
peer refused our addBA, so change that.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-09-21 16:14:14 +02:00
Christian Lamparter 2f7916f8d6 mac80211: request TX status for BlockAck Requests
Because ieee80211_tx_status in status.c checks if
outgoing BlockAck requests have been acked, it is
necessary to tell the driver that tx feedback for
this sort of frame is important.

Otherwise, the stack will continue to send the same
BlockAck request over and over, which can cause
the receiver to flush or clean its reorder buffer
over and over.

Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-07 21:35:42 +02:00
Johannes Berg bdcbd8e0e3 mac80211: clean up debugging
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: Johannes Berg <johannes.berg@intel.com>
2012-06-24 11:32:29 +02:00
Joe Perches d63e9ae3b1 net: mac80211: Add and use ht_vdbg debugging macro
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: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05 15:32:10 -04:00
Joe Perches f0d232080f net: mac80211: Convert printk(KERN_DEBUG to pr_debug
Standardize the debugging to be able to use dynamic_debug.

Coalesce formats, align arguments.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-05 15:27:16 -04:00
Johannes Berg 9e73dee7d3 mac80211: fix TX aggregation session timer
In commit 12d3952fc4
("mac80211: optimize aggregation session timeout handling")
two bugs were introduced:
 1) RCU usage was completely broken since no locks are held
 2) the timer must not rearm when agg session is stopping

Reported-and-tested-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-05-16 12:46:04 -04:00
Johannes Berg 3a25a8c8b7 mac80211: add improved HW queue control
mac80211 currently only supports one hardware queue
per AC. This is already problematic for off-channel
uses since if we go off channel while the BE queue
is full and then try to send an off-channel frame
the frame will never go out. This will become worse
when we support multi-channel since then a queue on
one channel might be full, but we have to stop the
software queue for all channels. That is obviously
not desirable.

To address this problem allow drivers to register
more hardware queues, and allow them to map them to
virtual interfaces. When they stop a hardware queue
the corresponding AC software queues on the correct
interfaces will be stopped as well. Additionally,
there's an off-channel queue to solve that problem
and a per-interface after-DTIM beacon queue. This
allows drivers to manage software queues closer to
how the hardware works.

Currently, there's a limit of 16 hardware queues.
This may or may not be sufficient, we can adjust it
as needed.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-04-11 16:23:50 -04:00
Felix Fietkau 12d3952fc4 mac80211: optimize aggregation session timeout handling
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: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-04-09 16:09:36 -04:00
Nikolay Martynov 84381b4ed5 mac80211: split addba retries in time
Currently code allows three (HT_AGG_MAX_RETRIES) unanswered addba
requests. When this limit is reached aggregation is turned off for
given TID permanently. This doesn't seem right: three requests is
not that much, some 'blackout' can happen, but effect of it affects
whole connection indefinitely.
  This patch increases number of retries to 15. Also, when there have
been 3 or more retries it splits further retries apart by 15 seconds
instead of sending them in very short period of time.

Signed-off-by: Nikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-12-19 14:31:37 -05:00
Helmut Schaa cf6bb79ad8 mac80211: Use appropriate TID for sending BAR, ADDBA and DELBA frames
Currently BAR, ADDBA and DELBA frames are always sent using AC_VO. If
the TID for which a BA session is established is assigned to a different
queue BAR, ADDBA and DELBA frames can "overtake" frames of the according
BA session.

Hence, always put BA session related frames into the same queue as the
BA sessions data frames.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-12-15 14:46:35 -05:00
John W. Linville 5d22df200b Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
Conflicts:
	drivers/net/wireless/iwlwifi/iwl-agn.c
2011-12-14 14:35:41 -05:00
Yogesh Ashok Powar 42624d4913 mac80211: Purge A-MPDU TX queues before station destructions
When a station leaves suddenly while ampdu traffic to that station is still
running, there is a possibility that the ampdu pending queues are not freed due
to a race condition leading to memory leaks. In '__sta_info_destroy' when we
attempt to destroy the ampdu sessions in 'ieee80211_sta_tear_down_BA_sessions',
the driver calls 'ieee80211_stop_tx_ba_cb_irqsafe' to delete the ampdu
structures (tid_tx) and splice the pending queues and this job gets queued in
sdata workqueue. However, the sta entry can get destroyed before the above work
gets scheduled and hence the race.

Purging the queues and freeing the tid_tx to avoid the leak. The better solution
would be to fix the race, but that can be taken up in a separate patch.

Signed-off-by: Nishant Sarmukadam <nishants@marvell.com>
Signed-off-by: Yogesh Ashok Powar <yogeshp@marvell.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-12-13 15:30:33 -05:00
Johannes Berg 15062e6a85 mac80211: fix another race in aggregation start
Emmanuel noticed that when mac80211 stops the queues
for aggregation that can leave a packet pending. This
packet will be given to the driver after the AMPDU
callback, but as a non-aggregated packet which messes
up the sequence number etc.

I also noticed by looking at the code that if packets
are being processed while we clear the WANT_START bit,
they might see it cleared already and queue up on
tid_tx->pending. If the driver then rejects the new
aggregation session we leak the packet.

Fix both of these issues by changing this code to not
stop the queues at all. Instead, let packets queue up
on the tid_tx->pending queue instead of letting them
get to the driver, and add code to recover properly
in case the driver rejects the session.

(The patch looks large because it has to move two
functions to before their new use.)

Cc: stable@vger.kernel.org
Reported-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-12-07 15:09:53 -05:00
Alexander Simon 13c40c5468 mac80211: Add HT operation modes for IBSS
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: Alexander 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: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-12-06 16:05:25 -05:00
Simon Wunderlich ff3cc5f40f mac80211: handle protection mode, RIFS and ADDBA for HT IBSS
* Follow 802.11n-2009 9.13.3.1 for protection mode and ADDBA
* Send ADDBA only to HT STAs - implement 11.5.1.1 partially

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-12-06 16:05:25 -05:00
John W. Linville d7a4858c0f Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
Conflicts:
	drivers/net/wireless/iwlwifi/iwl-agn.c
	drivers/net/wireless/libertas/cfg.c
2011-12-02 15:44:03 -05:00
Felix Fietkau bc192f8918 mac80211: do not pass AP VLAN vif pointers to drivers
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: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-11-28 14:43:52 -05:00
Nikolay Martynov 285fa6958c mac80211: timeout tx agg sessions in way similar to rx agg sessions
Currently tx aggregation is not being timed out even if timeout is
specified when aggregation is opened. Tx tid stays active until delba
arrives from recipient (i.e. recipient times out tid when it is
inactive).
  The problem with this approach is that delba can get lost in the air
and tx tid will stay perpetually opened on the originator while closed
on recipient thus all data sent via this tid will be lost.
  This patch implements tx tid timeouting in way very similar to rx tid
timeouting.

Signed-off-by: Nikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-11-28 14:43:49 -05:00
Emmanuel Grumbach 2a1e0fd175 mac80211: fix race between the AGG SM and the Tx data path
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>
2011-11-28 13:46:41 -05:00
Nikolay Martynov d305a6557b mac80211: fix race condition caused by late addBA response
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>
2011-11-28 13:46:41 -05:00
Johannes Berg 24f50a9d16 mac80211: don't stop a single aggregation session twice
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>
2011-11-28 13:46:41 -05:00
John W. Linville 515db09338 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux
Conflicts:
	drivers/net/wireless/iwlegacy/iwl-debugfs.c
	drivers/net/wireless/iwlegacy/iwl-rx.c
	drivers/net/wireless/iwlegacy/iwl-scan.c
	drivers/net/wireless/iwlegacy/iwl-tx.c
	include/net/bluetooth/bluetooth.h
2011-11-22 14:05:46 -05:00
Thomas Pedersen ae2772b313 mac80211: allow frame aggregation for mesh
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Ashok Nagarajan <anagar6@uic.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-11-08 15:55:27 -05:00
Paul Gortmaker bc3b2d7fb9 net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules
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: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:30 -04:00
Johannes Berg c2c98fdeb5 mac80211: optimise station flags
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: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-09-30 15:57:19 -04:00
Felix Fietkau 8c771244fb mac80211: make ieee80211_send_bar available for drivers
To properly maintain the peer's block ack window, the driver needs to be
able to control the new starting sequence number that is sent along with
the BlockAckReq frame.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-09-14 13:56:16 -04:00
Arik Nemtsov edf6b784c0 mac80211: add flag to indicate HW only Tx-agg setup support
When this flag is set, Tx A-MPDU sessions will not be started by
mac80211. This flag is required for devices that support Tx A-MPDU setup
in hardware.

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-09-13 15:45:03 -04:00
Joe Perches d15b84590a mac80211: Remove unnecessary OOM logging messages
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: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-09-13 15:45:02 -04:00
Helmut Schaa c1407b6cb2 wireless: Introduce defines for BAR TID_INFO & MULTI_TID fields
While at it also fix the indention of the other IEEE80211_BAR_CTRL_ defines.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-08-22 14:45:58 -04:00
Helmut Schaa 3ca97880ea mac80211: Stop TX BA session if buf_size is zero
If we receive an ADDBA response with status code 0 and a buf_size of 0
we should stop the TX BA session as otherwise we'll end up queuing
frames in ieee80211_tx_prep_agg forever instead of sending them out as
non AMPDUs.

This fixes a problem with AVM Fritz Stick N wireless devices where
frames to this device are not transmitted anymore by mac80211.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-08-08 16:04:08 -04:00
Linus Torvalds 06f4e926d2 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next-2.6: (1446 commits)
  macvlan: fix panic if lowerdev in a bond
  tg3: Add braces around 5906 workaround.
  tg3: Fix NETIF_F_LOOPBACK error
  macvlan: remove one synchronize_rcu() call
  networking: NET_CLS_ROUTE4 depends on INET
  irda: Fix error propagation in ircomm_lmp_connect_response()
  irda: Kill set but unused variable 'bytes' in irlan_check_command_param()
  irda: Kill set but unused variable 'clen' in ircomm_connect_indication()
  rxrpc: Fix set but unused variable 'usage' in rxrpc_get_transport()
  be2net: Kill set but unused variable 'req' in lancer_fw_download()
  irda: Kill set but unused vars 'saddr' and 'daddr' in irlan_provider_connect_indication()
  atl1c: atl1c_resume() is only used when CONFIG_PM_SLEEP is defined.
  rxrpc: Fix set but unused variable 'usage' in rxrpc_get_peer().
  rxrpc: Kill set but unused variable 'local' in rxrpc_UDP_error_handler()
  rxrpc: Kill set but unused variable 'sp' in rxrpc_process_connection()
  rxrpc: Kill set but unused variable 'sp' in rxrpc_rotate_tx_window()
  pkt_sched: Kill set but unused variable 'protocol' in tc_classify()
  isdn: capi: Use pr_debug() instead of ifdefs.
  tg3: Update version to 3.119
  tg3: Apply rx_discards fix to 5719/5720
  ...

Fix up trivial conflicts in arch/x86/Kconfig and net/mac80211/agg-tx.c
as per Davem.
2011-05-20 13:43:21 -07:00
Johannes Berg 40b275b69e mac80211: sparse RCU annotations
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: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-05-16 14:10:41 -04:00
Johannes Berg ec034b208d mac80211: fix TX a-MPDU locking
During my quest to make mac80211 not have any RCU
warnings from sparse, I came across the a-MPDU code
again and it wasn't quite clear why it isn't racy.
So instead of assigning the tid_tx array with just
the spinlock held in ieee80211_start_tx_ba_session
use a separate temporary array protected only by
the spinlock and protect all assignments to the
"live" array by both the spinlock and the mutex so
that other code is easily verified to be correct.

Due to pointer assignment atomicity I don't think
this is a real issue, but I'm not sure, especially
on Alpha the current code might be problematic.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-05-16 14:10:40 -04:00
Lai Jiangshan 0744371aeb net,rcu: convert call_rcu(kfree_tid_tx) to kfree_rcu()
The rcu callback kfree_tid_tx() just calls a kfree(),
so we use kfree_rcu() instead of the call_rcu(kfree_tid_tx).

Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Acked-by: "David S. Miller" <davem@davemloft.net>
2011-05-07 22:51:13 -07:00
Johannes Berg 5dd36bc933 mac80211: allow advertising correct maximum aggregate size
Currently, mac80211 always advertises that it may send
up to 64 subframes in an aggregate. This is fine, since
it's the max, but might as well be set to zero instead
since it doesn't have any information.

However, drivers might have that information, so allow
them to set a variable giving it, which will then be
used. The default of zero will be fine since to the
peer that means we don't know and it will just use its
own limit for the buffer size.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-01-19 11:36:12 -05:00
Johannes Berg 0b01f030d3 mac80211: track receiver's aggregation reorder buffer size
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: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2011-01-19 11:36:11 -05:00
Sujith Manoharan bd2ce6e43f mac80211: Add timeout to BA session start API
Allow drivers or rate control algorithms to specify BlockAck session
timeout when initiating an ADDBA transaction. This is useful in cases
where maintaining persistent BA sessions does not incur any overhead.

The current timeout value of 5000 TUs is retained for all non ath9k/ath9k_htc
drivers.

Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-12-15 17:03:59 -05:00
Johannes Berg 53f73c09d6 mac80211: avoid transmitting delBA to old AP
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: Johannes Berg <johannes.berg@intel.com>
Acked-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-10-06 16:30:40 -04:00
Johannes Berg 44271488b9 mac80211: delete AddBA response timer
We never delete the addBA response timer, which
is typically fine, but if the station it belongs
to is deleted very quickly after starting the BA
session, before the peer had a chance to reply,
the timer may fire after the station struct has
been freed already. Therefore, we need to delete
the timer in a suitable spot -- best when the
session is being stopped (which will happen even
then) in which case the delete will be a no-op
most of the time.

I've reproduced the scenario and tested the fix.

This fixes the crash reported at
http://mid.gmane.org/4CAB6F96.6090701@candelatech.com

Cc: stable@kernel.org
Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-10-06 15:58:29 -04:00
Johannes Berg 73a72a81d2 mac80211: update aggregation documentation
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: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:28 -04:00
Johannes Berg cfcdbde35e mac80211: change TX aggregation locking
To prepare for allowing drivers to sleep in
ampdu_action, change the locking in the TX
aggregation code to use the mutex the RX part
already uses. The spinlock is still necessary
around some code to avoid races with TX, but
now we can also synchronize_net() to avoid
getting an inconsistent sequence number.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:28 -04:00
Johannes Berg 83a5cbf73a mac80211: defer TX agg session teardown to work
Since we want the code to be able to sleep
in the future, it must not be called from
the timer directly. To achieve that, simply
call the function drivers would call, and
also use RCU in the timer to get the struct
so we don't need to rely on the spinlock in
the future.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:28 -04:00
Johannes Berg 67c282c00c mac80211: move BA session work
Move the block-ack session works into common
code, since it will be needed for RX agg too
in the next patches.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:27 -04:00
Johannes Berg 0ab337032a mac80211: make TX aggregation start/stop request async
When the driver or rate control requests starting
or stopping an aggregation session, that currently
causes a direct callback into the driver, which
could potentially cause locking problems. Also,
the functions need to be callable from contexts
that cannot sleep, and thus will interfere with
making the ampdu_action callback sleeping.

To address these issues, add a new work item for
each station that will process any start or stop
requests out of line.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:27 -04:00
Johannes Berg a6a67db2bc mac80211: refcount aggregation queue stop
mac80211 currently maintains the ampdu_lock to
avoid starting a queue due to one aggregation
session while another aggregation session needs
the queue stopped.

We can do better, however, and instead refcount
the queue stops for this particular purpose,
thus removing the need for the lock. This will
help making ampdu_action able to sleep.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:27 -04:00
Johannes Berg 5d22c89b9b mac80211: remove non-irqsafe aggregation callbacks
The non-irqsafe aggregation start/stop done
callbacks are currently only used by ath9k_htc,
and can cause callbacks into the driver again.
This might lead to locking issues, which will
only get worse as we modify locking. To avoid
trouble, remove the non-irqsafe versions and
change ath9k_htc to use those instead.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:27 -04:00
Johannes Berg a622ab72b4 mac80211: use RCU for TX aggregation
Currently we allocate some memory for each TX
aggregation session and additionally keep a
state bitmap indicating the state it is in.
By using RCU to protect the pointer, moving
the state into the structure and some locking
trickery we can avoid locking when the TX agg
session is fully operational.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:27 -04:00
Johannes Berg c1475ca99e mac80211: move aggregation callback processing
This moves the aggregation callback processing
to the per-sdata skb queue and a work function
rather than the tasklet.

Unfortunately, this means that it extends the
pkt_type hack to that skb queue. However, it
will enable making ampdu_action API changes
gradually, my current plan is to get rid of
this again by forcing drivers to only return
from ampdu_action() when everything is done,
thus removing the callbacks completely.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-06-14 15:39:27 -04:00