Commit Graph

81 Commits

Author SHA1 Message Date
Johannes Berg 6cb5f3ea46 mac80211: populate debugfs only after cfg80211 init
When fixing the initialization race, we neglected to account for
the fact that debugfs is initialized in wiphy_register(), and
some debugfs things went missing (or rather were rerooted to the
global debugfs root).

Fix this by adding debugfs entries only after wiphy_register().
This requires some changes in the rate control code since it
currently adds debugfs at alloc time, which can no longer be
done after the reordering.

Reported-by: Jouni Malinen <j@w1.fi>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Reported-by: Hauke Mehrtens <hauke@hauke-m.de>
Reported-by: Felix Fietkau <nbd@nbd.name>
Cc: stable@vger.kernel.org
Fixes: 52e04b4ce5 ("mac80211: fix race in ieee80211_register_hw()")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Sumit Garg <sumit.garg@linaro.org>
Link: https://lore.kernel.org/r/20200423111344.0e00d3346f12.Iadc76a03a55093d94391fc672e996a458702875d@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2020-04-24 11:30:13 +02:00
David S. Miller 92ad6325cb Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Minor SPDX change conflict.

Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-22 08:59:24 -04:00
Thomas Gleixner d2912cb15b treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500
Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:55 +02:00
Johannes Berg 163a7cdd1f mac80211: extend __rate_control_send_low warning
This appears to happen occasionally, and if it does we
really want even more information than we have now.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-06-14 14:18:05 +02:00
Johannes Berg 583a7a34c5 mac80211: fill low rate even for HAS_RATE_CONTROL
If HW advertises it has rate control, we skip all of the
rate control assignments, but sometimes the data we have
here is useful, especially so that we don't have to do
the lookups again on which rates are configured and are
supported.

So do the low rate assignment anyway to help out drivers
that might need it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-06-14 14:17:55 +02:00
Johannes Berg bd718fc11d mac80211: use STA info in rate_control_send_low()
Even if we have a station, we currently call rate_control_send_low()
with the NULL station unless further rate control (driver, minstrel)
has been initialized.

Change this so we can use more information about the station to use
a better rate. For example, when we associate with an AP, we will
now use the lowest rate it advertised as supported (that we can)
rather than the lowest mandatory rate. This aligns our behaviour
with most other 802.11 implementations.

To make this possible, we need to also ensure that we have non-zero
rates at all times, so in case we really have *nothing* pre-fill
the supp_rates bitmap with the very lowest mandatory bitmap (11b
and 11a on 2.4 and 5 GHz respectively).

Additionally, hostapd appears to be giving us an empty supported
rates bitmap (it can and should do better, since the STA must have
supported for at least the basic rates in the BSS), so ignore any
such bitmaps that would actually zero out the supp_rates, and in
that case just keep the pre-filled mandatory rates.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-06-14 14:17:37 +02:00
Johannes Berg 1e87fec9fa mac80211: call rate_control_send_low() internally
There's no rate control algorithm that *doesn't* want to call
it internally, and calling it internally will let us modify
its behaviour in the future.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-06-14 14:17:37 +02:00
Toke Høiland-Jørgensen 484a54c2e5 mac80211: Dynamically set CoDel parameters per station
CoDel can be too aggressive if a station sends at a very low rate,
leading reduced throughput. This gets worse the more stations are
present, as each station gets more bursty the longer the round-robin
scheduling between stations takes.

This adds dynamic adjustment of CoDel parameters per station. It uses
the rate selection information to estimate throughput and sets more
lenient CoDel parameters if the estimated throughput is below a
threshold (modified by the number of active stations).

A new callback is added that drivers can use to notify mac80211 about
changes in expected throughput, so the same adjustment can be made for
cards that implement rate control in firmware. Drivers that don't use
this will just get the default parameters.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
[remove currently unnecessary EXPORT_SYMBOL, fix kernel-doc, remove
inline annotation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-05-17 16:03:40 +02:00
Mohammed Shafi Shajakhan 21a8e9dd52 mac80211: Fix possible sband related NULL pointer de-reference
Existing API 'ieee80211_get_sdata_band' returns default 2 GHz band even
if the channel context configuration is NULL. This crashes for chipsets
which support 5 Ghz alone when it tries to access members of 'sband'.
Channel context configuration can be NULL in multivif case and when
channel switch is in progress (or) when it fails. Fix this by replacing
the API 'ieee80211_get_sdata_band' with  'ieee80211_get_sband' which
returns a NULL pointer for sband when the channel configuration is NULL.

An example scenario is as below:

In multivif mode (AP + STA) with drivers like ath10k, when we do a
channel switch in the AP vif (which has a number of clients connected)
and a STA vif which is connected to some other AP, when the channel
switch in AP vif fails, while the STA vifs tries to connect to the
other AP, there is a window where the channel context is NULL/invalid
and this results in a crash  while the clients connected to the AP vif
tries to reconnect and this race is very similar to the one investigated
by Michal in https://patchwork.kernel.org/patch/3788161/ and this does
happens with hardware that supports 5Ghz alone after long hours of
testing with continuous channel switch on the AP vif

ieee80211 phy0: channel context reservation cannot be finalized because
some interfaces aren't switching
wlan0: failed to finalize CSA, disconnecting
wlan0-1: deauthenticating from 8c:fd:f0:01:54:9c by local choice
	(Reason: 3=DEAUTH_LEAVING)

	WARNING: CPU: 1 PID: 19032 at net/mac80211/ieee80211_i.h:1013 sta_info_alloc+0x374/0x3fc [mac80211]
	[<bf77272c>] (sta_info_alloc [mac80211])
	[<bf78776c>] (ieee80211_add_station [mac80211]))
	[<bf73cc50>] (nl80211_new_station [cfg80211])

	Unable to handle kernel NULL pointer dereference at virtual
	address 00000014
	pgd = d5f4c000
	Internal error: Oops: 17 [#1] PREEMPT SMP ARM
	PC is at sta_info_alloc+0x380/0x3fc [mac80211]
	LR is at sta_info_alloc+0x37c/0x3fc [mac80211]
	[<bf772738>] (sta_info_alloc [mac80211])
	[<bf78776c>] (ieee80211_add_station [mac80211])
	[<bf73cc50>] (nl80211_new_station [cfg80211]))

Cc: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-04-28 12:28:44 +02:00
Felix Fietkau 18fb84d986 mac80211: make rate control tx status API more extensible
Rename .tx_status_noskb to .tx_status_ext and pass a new on-stack
struct ieee80211_tx_status instead of struct ieee80211_tx_info.

This struct can be used to pass extra information, e.g. for dynamic tx
power control

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-04-28 10:57:33 +02:00
Matthias Kaehlcke 93f56de259 mac80211: Fix clang warning about constant operand in logical operation
When clang detects a non-boolean constant in a logical operation it
generates a 'constant-logical-operand' warning. In
ieee80211_try_rate_control_ops_get() the result of strlen(<const str>)
is used in a logical operation, clang resolves the expression to an
(integer) constant at compile time when clang's builtin strlen function
is used.

Change the condition to check for strlen() > 0 to make the constant
operand boolean and thus avoid the warning.

Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-04-13 08:27:02 +02:00
Johannes Berg e8e4f5280d mac80211: reject/clear user rate mask if not usable
If the user rate mask results in no (basic) rates being usable,
clear it. Also, if we're already operating when it's set, reject
it instead.

Technically, selecting basic rates as the criterion is a bit too
restrictive, but calculating the usable rates over all stations
(e.g. in AP mode) is harder, and all stations must support the
basic rates. Similarly, in client mode, the basic rates will be
used anyway for control frames.

This fixes the "no supported rates (...) in rate_mask ..." warning
that occurs on TX when you've selected a rate mask that's not
compatible with the connection (e.g. an AP that enables only the
rates 36, 48, 54 and you've selected only 6, 9, 12.)

Reported-by: Kirtika Ruchandani <kirtika@google.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-03-08 14:20:01 +01:00
Johannes Berg a858958b68 mac80211: remove local pointer from rate_ctrl_ref
This pointer really isn't needed, so remove it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-03-06 09:21:43 +01:00
Johannes Berg 115865fa08 mac80211: don't try to sleep in rate_control_rate_init()
In my previous patch, I missed that rate_control_rate_init() is
called from some places that cannot sleep, so it cannot call
ieee80211_recalc_min_chandef(). Remove that call for now to fix
the context bug, we'll have to find a different way to fix the
minimum channel width issue.

Fixes: 96aa2e7cf1 ("mac80211: calculate min channel width correctly")
Reported-by: Xiaolong Ye (via lkp-robot) <xiaolong.ye@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-01-24 16:31:54 +01:00
Johannes Berg 96aa2e7cf1 mac80211: calculate min channel width correctly
In the current minimum chandef code there's an issue in that the
recalculation can happen after rate control is initialized for a
station that has a wider bandwidth than the current chanctx, and
then rate control can immediately start using those higher rates
which could cause problems.

Observe that first of all that this problem is because we don't
take non-associated and non-uploaded stations into account. The
restriction to non-associated is quite pointless and is one of
the causes for the problem described above, since the rate init
will happen before the station is set to associated; no frames
could actually be sent until associated, but the rate table can
already contain higher rates and that might cause problems.

Also, rejecting non-uploaded stations is wrong, since the rate
control can select higher rates for those as well.

Secondly, it's then necessary to recalculate the minimal config
before initializing rate control, so that when rate control is
initialized, the higher rates are already available. This can be
done easily by adding the necessary function call in rate init.

Change-Id: Ib9bc02d34797078db55459d196993f39dcd43070
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2017-01-11 16:34:51 +01:00
Johannes Berg 57fbcce37b cfg80211: remove enum ieee80211_band
This enum is already perfectly aliased to enum nl80211_band, and
the only reason for it is that we get IEEE80211_NUM_BANDS out of
it. There's no really good reason to not declare the number of
bands in nl80211 though, so do that and remove the cfg80211 one.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-04-12 15:56:15 +02:00
Johannes Berg ef95d8ba38 mac80211: further improve "no supported rates" warning
Allow distinguishing the non-station case from the case of a
station without rates, by using -1 for the non-station case.
This value cannot be reached with a station since that many
legacy rates don't exist.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-11-03 10:56:42 +01:00
David S. Miller 2579c98f0d For the current cycle, we have the following right now:
* many internal fixes, API improvements, cleanups, etc.
  * full AP client state tracking in cfg80211/mac80211 from Ayala
  * VHT support (in mac80211) for mesh
  * some A-MSDU in A-MPDU support from Emmanuel
  * show current TX power to userspace (from Rafał)
  * support for netlink dump in vendor commands (myself)
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Merge tag 'mac80211-next-for-davem-2015-10-05' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
For the current cycle, we have the following right now:
 * many internal fixes, API improvements, cleanups, etc.
 * full AP client state tracking in cfg80211/mac80211 from Ayala
 * VHT support (in mac80211) for mesh
 * some A-MSDU in A-MPDU support from Emmanuel
 * show current TX power to userspace (from Rafał)
 * support for netlink dump in vendor commands (myself)
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-10-07 04:29:18 -07:00
Johannes Berg 0e5c371aa0 mac80211: improve __rate_control_send_low warning
If there are no supported rates in the rate mask with the required
flags, we warn, but it's not clear which part causes the warning.

Add the relevant data to the warning to understand why it happens.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-09-29 15:56:48 +02:00
Thierry Reding 98a1f8282b mac80211: Do not use sizeof() on pointer type
The rate_control_cap_mask() function takes a parameter mcs_mask, which
GCC will take to be u8 * even though it was declared with a fixed size.
This causes the following warning:

	net/mac80211/rate.c: In function 'rate_control_cap_mask':
	net/mac80211/rate.c:719:25: warning: 'sizeof' on array function parameter 'mcs_mask' will return size of 'u8 * {aka unsigned char *}' [-Wsizeof-array-argument]
	   for (i = 0; i < sizeof(mcs_mask); i++)
	                         ^
	net/mac80211/rate.c:684:10: note: declared here
	       u8 mcs_mask[IEEE80211_HT_MCS_MASK_LEN],
	          ^

This can be easily fixed by using the IEEE80211_HT_MCS_MASK_LEN directly
within the loop condition.

Signed-off-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-09-04 14:23:08 +02:00
Lorenzo Bianconi b119ad6e72 mac80211: add rate mask logic for vht rates
Define rc_rateidx_vht_mcs_mask array and rate_idx_match_vht_mcs_mask()
method in order to apply mcs mask for vht rates

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-08-14 17:49:51 +02:00
Lorenzo Bianconi e910867bd2 mac80211: define rate_control_apply_mask_ratetbl()
Define rate_control_apply_mask_ratetbl() in order to apply ratemask in
rate_control_set_rates() for station rate table

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-08-14 17:49:51 +02:00
Lorenzo Bianconi 90c66bd223 mac80211: remove ieee80211_tx_rate dependency in rate mask code
Remove ieee80211_tx_rate dependency in rate_idx_match_legacy_mask(),
rate_idx_match_mcs_mask() and rate_idx_match_mask() in order to use the
previous logic to define a ratemask in rate_control_set_rates() for
station rate table. Moreover move rate mask definition logic in
rate_control_cap_mask()

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-08-14 17:49:50 +02:00
Lorenzo Bianconi 35225eb7a5 mac80211: remove ieee80211_tx_info from rate_control_apply_mask signature
Remove unnecessary ieee80211_tx_info pointer from rate_control_apply_mask
signature. rate_control_apply_mask() will be used to define a ratemask in
rate_control_set_rates() for station rate table

Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-08-14 17:49:50 +02:00
Denys Vlasenko eb6d9293df mac80211: deinline rate_control_rate_init, rate_control_rate_update
With this .config: http://busybox.net/~vda/kernel_config,
after deinlining these functions have sizes and callsite counts
as follows:

rate_control_rate_init: 554 bytes, 8 calls
rate_control_rate_update: 1596 bytes, 5 calls

Total size reduction: about 11 kbytes.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
CC: John Linville <linville@tuxdriver.com>
CC: Michal Kazior <michal.kazior@tieto.com>
CC: Johannes Berg <johannes.berg@intel.com>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:50:02 +02:00
Linus Torvalds 02201e3f1b Minor merge needed, due to function move.
Main excitement here is Peter Zijlstra's lockless rbtree optimization to
 speed module address lookup.  He found some abusers of the module lock
 doing that too.
 
 A little bit of parameter work here too; including Dan Streetman's breaking
 up the big param mutex so writing a parameter can load another module (yeah,
 really).  Unfortunately that broke the usual suspects, !CONFIG_MODULES and
 !CONFIG_SYSFS, so those fixes were appended too.
 
 Cheers,
 Rusty.
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Merge tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

Pull module updates from Rusty Russell:
 "Main excitement here is Peter Zijlstra's lockless rbtree optimization
  to speed module address lookup.  He found some abusers of the module
  lock doing that too.

  A little bit of parameter work here too; including Dan Streetman's
  breaking up the big param mutex so writing a parameter can load
  another module (yeah, really).  Unfortunately that broke the usual
  suspects, !CONFIG_MODULES and !CONFIG_SYSFS, so those fixes were
  appended too"

* tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (26 commits)
  modules: only use mod->param_lock if CONFIG_MODULES
  param: fix module param locks when !CONFIG_SYSFS.
  rcu: merge fix for Convert ACCESS_ONCE() to READ_ONCE() and WRITE_ONCE()
  module: add per-module param_lock
  module: make perm const
  params: suppress unused variable error, warn once just in case code changes.
  modules: clarify CONFIG_MODULE_COMPRESS help, suggest 'N'.
  kernel/module.c: avoid ifdefs for sig_enforce declaration
  kernel/workqueue.c: remove ifdefs over wq_power_efficient
  kernel/params.c: export param_ops_bool_enable_only
  kernel/params.c: generalize bool_enable_only
  kernel/module.c: use generic module param operaters for sig_enforce
  kernel/params: constify struct kernel_param_ops uses
  sysfs: tightened sysfs permission checks
  module: Rework module_addr_{min,max}
  module: Use __module_address() for module_address_lookup()
  module: Make the mod_tree stuff conditional on PERF_EVENTS || TRACING
  module: Optimize __module_address() using a latched RB-tree
  rbtree: Implement generic latch_tree
  seqlock: Introduce raw_read_seqcount_latch()
  ...
2015-07-01 10:49:25 -07:00
Dan Streetman b51d23e4e9 module: add per-module param_lock
Add a "param_lock" mutex to each module, and update params.c to use
the correct built-in or module mutex while locking kernel params.
Remove the kparam_block_sysfs_r/w() macros, replace them with direct
calls to kernel_param_[un]lock(module).

The kernel param code currently uses a single mutex to protect
modification of any and all kernel params.  While this generally works,
there is one specific problem with it; a module callback function
cannot safely load another module, i.e. with request_module() or even
with indirect calls such as crypto_has_alg().  If the module to be
loaded has any of its params configured (e.g. with a /etc/modprobe.d/*
config file), then the attempt will result in a deadlock between the
first module param callback waiting for modprobe, and modprobe trying to
lock the single kernel param mutex to set the new module's param.

This fixes that by using per-module mutexes, so that each individual module
is protected against concurrent changes in its own kernel params, but is
not blocked by changes to other module params.  All built-in modules
continue to use the built-in mutex, since they will always be loaded at
runtime and references (e.g. request_module(), crypto_has_alg()) to them
will never cause load-time param changing.

This also simplifies the interface used by modules to block sysfs access
to their params; while there are currently functions to block and unblock
sysfs param access which are split up by read and write and expect a single
kernel param to be passed, their actual operation is identical and applies
to all params, not just the one passed to them; they simply lock and unlock
the global param mutex.  They are replaced with direct calls to
kernel_param_[un]lock(THIS_MODULE), which locks THIS_MODULE's param_lock, or
if the module is built-in, it locks the built-in mutex.

Suggested-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Dan Streetman <ddstreet@ieee.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2015-06-23 15:27:38 +09:30
Johannes Berg 30686bf7f5 mac80211: convert HW flags to unsigned long bitmap
As we're running out of hardware capability flags pretty quickly,
convert them to use the regular test_bit() style unsigned long
bitmaps.

This introduces a number of helper functions/macros to set and to
test the bits, along with new debugfs code.

The occurrences of an explicit __clear_bit() are intentional, the
drivers were never supposed to change their supported bits on the
fly. We should investigate changing this to be a per-frame flag.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-06-10 16:05:36 +02:00
Johannes Berg 35c347ac53 mac80211: lock rate control
Both minstrel (reported by Sven Eckelmann) and the iwlwifi rate
control aren't properly taking concurrency into account. It's
likely that the same is true for other rate control algorithms.

In the case of minstrel this manifests itself in crashes when an
update and other data access are run concurrently, for example
when the stations change bandwidth or similar. In iwlwifi, this
can cause firmware crashes.

Since fixing all rate control algorithms will be very difficult,
just provide locking for invocations. This protects the internal
data structures the algorithms maintain.

I've manipulated hostapd to test this, by having it change its
advertised bandwidth roughly ever 150ms. At the same time, I'm
running a flood ping between the client and the AP, which causes
this race of update vs. get_rate/status to easily happen on the
client. With this change, the system survives this test.

Reported-by: Sven Eckelmann <sven@open-mesh.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-04-20 13:05:29 +02:00
Felix Fietkau 336004e291 mac80211: add more missing checks for VHT tx rates
Fixes a crash on attempting to calculate the frame duration for a VHT
packet (which needs to be handled by hw/driver instead).

Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-11-28 14:24:23 +01:00
Johannes Berg f815e2b3c0 mac80211: notify drivers on sta rate table changes
This allows drivers with a firmware or chip-based rate lookup table to
use the most recent default rate selection without having to get it from
per-packet data or explicit ieee80211_get_tx_rate calls

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-11-19 19:15:50 +01:00
Felix Fietkau 628c010f1f mac80211: skip legacy rate mask handling for VHT rates
The rate mask code currently assumes that a rate is legacy if
IEEE80211_TX_RC_MCS is not set. This might be the cause of bogus VHT
rates being reported with minstrel_ht.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-11-19 18:46:35 +01:00
Karl Beldan c7abf25af0 mac80211: fix typo in starting baserate for rts_cts_rate_idx
It affects non-(V)HT rates and can lead to selecting an rts_cts rate
that is not a basic rate or way superior to the reference rate (ATM
rates[0] used for the 1st attempt of the protected frame data).

E.g, assuming drivers register growing (bitrate) sorted tables of
ieee80211_rate-s, having :
- rates[0].idx == d'2 and basic_rates == b'10100
will select rts_cts idx b'10011 & ~d'(BIT(2)-1), i.e. 1, likewise
- rates[0].idx == d'2 and basic_rates == b'10001
will select rts_cts idx b'10000
The first is not a basic rate and the second is > rates[0].

Also, wrt severity of the addressed misbehavior, ATM we only have one
rts_cts_rate_idx rather than one per rate table entry, so this idx might
still point to bitrates > rates[1..MAX_RATES].

Fixes: 5253ffb8c9 ("mac80211: always pick a basic rate to tx RTS/CTS for pre-HT rates")
Cc: stable@vger.kernel.org
Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-10-14 11:16:16 +02:00
Johannes Berg cc01f9b55f mac80211: remove module handling from rate control ops
There's not a single rate control algorithm actually in
a separate module where the module refcount would be
required. Similarly, there's no specific rate control
module.

Therefore, all the module handling code in rate control
is really just dead code, so remove it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-02-04 21:48:26 +01:00
Johannes Berg 631ad703ba mac80211: make rate control ops const
Change the code to allow making all the rate control ops
const, nothing ever needs to change them. Also change all
drivers to make use of this and mark the ops const.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-02-04 21:48:21 +01:00
Andrei Otcheretianski 1d2d350bbf mac80211: respect rate mask in TX
Bitrate mask were not respected in transmissions, causing (for
example) P2P GO/client to use CCK rates for auth and assoc frames.
Fix it by considering the rate mask in __rate_control_send_low().

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-10-15 15:16:29 +02:00
Andrei Otcheretianski 1431fcb74e mac80211: fix honouring rate flags in low-rate transmit
Transmissions with the IEEE80211_TX_CTL_NO_CCK_RATE flag set
(which can come from userspace) were no longer guaranteed to
be transmitted with allowed rates since commit 2103dec147
("mac80211: select and adjust bitrates according to channel
mode") due to a missing rate_flags check in that commit. The
commit also introduced the need to check the 5/10 MHz flags
but accidentally didn't. Fix it by adding the missing check.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-10-15 15:16:12 +02:00
Chun-Yeow Yeoh 0670307992 mac80211: allow lowest basic rate for unicast management for mesh
Allow lowest basic rate to be used for unicast management frame in
mesh. Otherwise, the lowest supported rate is used for unicast
management frame, such as 1Mbps for 2.4GHz and 6Mbps for 5GHz. Rename
the rc_send_low_broadcast to re_send_low_basicrate since now it is
also applied to unicast management frame in mesh.

Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-08-09 15:11:27 +02:00
Simon Wunderlich 2103dec147 mac80211: select and adjust bitrates according to channel mode
The various components accessing the bitrates table must use consider
the used channel bandwidth to select only available rates or calculate
the bitrate correctly.

There are some rates in reduced bandwidth modes which can't be
represented as multiples of 500kbps, like 2.25 MBit/s in 5 MHz mode. The
standard suggests to round up to the next multiple of 500kbps, just do
that in mac80211 as well.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
[make rate unsigned in ieee80211_add_tx_radiotap_header(), squash fix]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
2013-07-16 09:58:06 +03:00
Johannes Berg f93beba705 Merge remote-tracking branch 'mac80211/master' into HEAD
Merge mac80211 to avoid conflicts with the nl80211 attrbuf
changes.

Conflicts:
	net/mac80211/iface.c
	net/wireless/nl80211.c

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-06-19 18:55:12 +02:00
Simon Wunderlich 0418a44583 mac80211: fix various components for the new 5 and 10 MHz widths
This is a collection of minor fixes:
 * don't allow HT IEs in IBSS for 5/10 MHz
 * don't allow HT IEs in Mesh for 5/10 MHz
 * don't downgrade from/to 5 and 10 MHz channels
 * don't try HT rates for 5 and 10 MHz channels when selecting rates

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-06-18 16:17:11 +02:00
Simon Wunderlich 795d855d56 mac80211: Fix rate control mask matching call
The order of parameters was mixed up, introduced in commit
"mac80211: improve the rate control API"

Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-06-12 09:12:43 +02:00
Felix Fietkau f6b3d85f7f mac80211: fix spurious RCU warning and update documentation
Document rx vs tx status concurrency requirements.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-05-16 22:38:05 +02:00
Felix Fietkau 0d528d85c5 mac80211: improve the rate control API
Allow rate control modules to pass a rate selection table to mac80211
and the driver. This allows drivers to fetch the most recent rate
selection from the sta pointer for already buffered frames. This allows
rate control to respond faster to sudden link changes and it is also a
step towards adding minstrel_ht support to drivers like iwlwifi.

When a driver sets IEEE80211_HW_SUPPORTS_RC_TABLE, mac80211 will not
fill info->control.rates with rates from the rate table (to preserve
explicit overrides by the rate control module). The driver then
explicitly calls ieee80211_get_tx_rates to merge overrides from
info->control.rates with defaults from the sta rate table.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-04-22 16:16:41 +02:00
Felix Fietkau 2ffbe6d333 mac80211: fix and optimize MCS mask handling
Currently the code always copies the configured MCS mask (even if it is
set to default), but only uses it if legacy rates were also masked out.
Fix this by adding a flag that tracks whether the configured MCS mask is
set to default or not.
Optimize the code further by storing a pointer to the configured rate
mask in txrc instead of using memcpy.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-04-16 23:42:29 +02:00
Johannes Berg 4bf88530be mac80211: convert to channel definition struct
Convert mac80211 (and where necessary, some drivers a
little bit) to the new channel definition struct.

This will allow extending mac80211 for VHT, which is
currently restricted to channel contexts since there
are no drivers using that which makes it easier. As
I also don't care about VHT for drivers not using the
channel context API, I won't convert the previous API
to VHT support.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-11-26 12:42:59 +01:00
Stephen Boyd 234e340582 simple_open: automatically convert to simple_open()
Many users of debugfs copy the implementation of default_open() when
they want to support a custom read/write function op.  This leads to a
proliferation of the default_open() implementation across the entire
tree.

Now that the common implementation has been consolidated into libfs we
can replace all the users of this function with simple_open().

This replacement was done with the following semantic patch:

<smpl>
@ open @
identifier open_f != simple_open;
identifier i, f;
@@
-int open_f(struct inode *i, struct file *f)
-{
(
-if (i->i_private)
-f->private_data = i->i_private;
|
-f->private_data = i->i_private;
)
-return 0;
-}

@ has_open depends on open @
identifier fops;
identifier open.open_f;
@@
struct file_operations fops = {
...
-.open = open_f,
+.open = simple_open,
...
};
</smpl>

[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-04-05 15:25:50 -07:00
David S. Miller b4017c5368 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/ethernet/broadcom/tg3.c

Conflicts in the statistics regression bug fix from 'net',
but happily Matt Carlson originally posted the fix against
'net-next' so I used that to resolve this.

Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-01 17:57:40 -05:00
Mohammed Shafi Shajakhan 8617b093d0 mac80211: zero initialize count field in ieee80211_tx_rate
rate control algorithms concludes the rate as invalid
with rate[i].idx < -1 , while they do also check for rate[i].count is
non-zero. it would be safer to zero initialize the 'count' field.
recently we had a ath9k rate control crash where the ath9k rate control
in ath_tx_status assumed to check only for rate[i].count being non-zero
in one instance and ended up in using invalid rate index for
'connection monitoring NULL func frames' which eventually lead to the crash.
thanks to Pavel Roskin for fixing it and finding the root cause.
https://bugzilla.redhat.com/show_bug.cgi?id=768639

Cc: stable@vger.kernel.org
Cc: Pavel Roskin <proski@gnu.org>
Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-02-21 14:45:26 -05:00
Johannes Berg 4b5a433ae5 mac80211: call rate control only after init
There are situations where we don't have the
necessary rate control information yet for
station entries, e.g. when associating. This
currently doesn't really happen due to the
dummy station handling; explicitly disabling
rate control when it's not initialised will
allow us to remove dummy stations.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-02-15 13:56:06 -05:00