wifi: mac80211: track capability/opmode NSS separately

We're currently tracking rx_nss for each station, and that
is meant to be initialized to the capability NSS and later
reduced by the operating mode notification NSS.

However, we're mixing up capabilities and operating mode
NSS in the same variable. This forces us to recalculate
the NSS capability on operating mode notification RX,
which is a bit strange; due to the previous fix I had to
never keep rx_nss as zero, it also means that the capa is
never taken into account properly.

Fix all this by storing the capability value, that can be
recalculated unconditionally whenever needed, and storing
the operating mode notification NSS separately, taking it
into account when assigning the final rx_nss value.

Cc: stable@vger.kernel.org
Fixes: dd6c064cfc3f ("wifi: mac80211: set station RX-NSS on reconfig")
Reviewed-by: Miriam Rachel Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240228120157.0e1c41924d1d.I0acaa234e0267227b7e3ef81a59117c8792116bc@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: flush only stations using requests links

Whenever sta_flush() function is invoked, all STAs present in that
interface are flushed. In case of MLO, it is desirable to only flush such
STAs that are at least using a given link id as one of their links.

Add support for this by making change in the __sta_info_flush API argument
to accept a link ID. And then, only if the STA is using the given link as
one of its links, it would be flushed.

Signed-off-by: Aditya Kumar Singh <quic_adisi@quicinc.com>
Link: https://msgid.link/20240205162952.1697646-3-quic_adisi@quicinc.com
[reword commit message, in particular this isn't about "active" links]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: cleanup airtime arithmetic with ieee80211_sta_keep_active()

Prefer native jiffies-wide 'unsigned long' for the 'last_active' field of
'struct airtime_info' and introduce 'ieee80211_sta_keep_active()' for airtime
check in 'ieee80211_txq_keep_active()' and 'ieee80211_sta_register_airtime()'.

Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Reviewed-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://msgid.link/20231206060935.612241-1-dmantipov@yandex.ru
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: fix various kernel-doc issues

There are various kernel-doc issues here, fix them.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230827135854.7ce9761f9ebb.I0f44e76c518f72135cc855c809bfa7a5e977b894@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: remove ampdu_mlme.mtx

We now hold the wiphy mutex everywhere that we use or
needed the A-MPDU locking, so we don't need this mutex
any more. Remove it.

Most of this change was done automatically with spatch.

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

wifi: mac80211: remove sta_mtx

We now hold the wiphy mutex everywhere that we use or
needed the sta_mtx, so we don't need this mutex any
more. Remove it.

Most of this change was done automatically with spatch.

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

wifi: mac80211: convert A-MPDU work to wiphy work

Convert the A-MPDU work to wiphy work so it holds the
wiphy mutex and we can later guarantee that to drivers.
It might seem that we could run these concurrently for
different stations, but they're all on the ordered
mac80211 workqueue, so this shouldn't matter for that.

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

wifi: mac80211: use bullet list for amsdu_mesh_control formats list

Commit fe4a6d2db3ba ("wifi: mac80211: implement support for yet
another mesh A-MSDU format") expands amsdu_mesh_control list to
multi-line list. However, the expansion triggers Sphinx warning:

Documentation/driver-api/80211/mac80211-advanced:214: ./net/mac80211/sta_info.h:628: WARNING: Unexpected indentation.

Use bullet list instead to fix the warning.

Link: https://lore.kernel.org/linux-next/20230323141548.659479ef@canb.auug.org.au/
Fixes: fe4a6d2db3bad4 ("wifi: mac80211: implement support for yet another mesh A-MSDU format")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: implement support for yet another mesh A-MSDU format

MT7996 hardware supports mesh A-MSDU subframes in hardware, but uses a
big-endian length field

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Ryder Lee <ryder.lee@mediatek.com>
Link: https://lore.kernel.org/r/20230314095956.62085-7-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: add documentation for amsdu_mesh_control

This documentation wasn't added in the original patch,
add it now.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: 6e4c0d0460bd ("wifi: mac80211: add a workaround for receiving non-standard mesh A-MSDU")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: add a workaround for receiving non-standard mesh A-MSDU

At least ath10k and ath11k supported hardware (maybe more) does not implement
mesh A-MSDU aggregation in a standard compliant way.
802.11-2020 9.3.2.2.2 declares that the Mesh Control field is part of the
A-MSDU header (and little-endian).
As such, its length must not be included in the subframe length field.
Hardware affected by this bug treats the mesh control field as part of the
MSDU data and sets the length accordingly.
In order to avoid packet loss, keep track of which stations are affected
by this and take it into account when converting A-MSDU to 802.3 + mesh control
packets.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20230213100855.34315-5-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: support minimal EHT rate reporting on RX

Add minimal support for RX EHT rate reporting, not yet
adding (modifying) any radiotap headers, just statistics
for cfg80211.

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

wifi: mac80211: recalc station aggregate data during link switch

During link switching, the active links change, so we need to
recalculate the aggregate data in the stations.

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

wifi: mac80211: add API to show the link STAs in debugfs

Create debugfs data per-link. For drivers, there is a new operation
link_sta_add_debugfs which will always be called.

For non-MLO, the station directory will be used directly rather than
creating a corresponding subdirectory. As such, non-MLO drivers can
simply continue to create the data from sta_debugfs_add.

Signed-off-by: Benjamin Berg <benjamin.berg@intel.com>
[add missing inlines if !CONFIG_MAC80211_DEBUGFS]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: keep A-MSDU data in sta and per-link

The A-MSDU data needs to be stored per-link and aggregated into a single
value for the station. Add a new struct ieee_80211_sta_aggregates in
order to store this data and a new function
ieee80211_sta_recalc_aggregates to update the current data for the STA.

Note that in the non MLO case the pointer in ieee80211_sta will directly
reference the data in deflink.agg, which means that recalculation may be
skipped in that case.

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

wifi: mac80211: fix up link station creation/insertion

When we create a station with a non-default link, then
we should have a link address, and we definitely need
to insert it into the link hash table on insertion.

Split the API into with and without link creation and
if it has a link, insert the link into the link hash
table on sta_info_insert().

Fixes: ba6ddab94fc6 ("wifi: mac80211: maintain link-sta hash table")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: limit A-MSDU subframes for client too

In AP/mesh where the stations are added by userspace, we
limit the number of A-MSDU subframes according to the
extended capabilities.

Refactor the code and extend that also to client-side.

Fixes: 506bcfa8abeb ("mac80211: limit the A-MSDU Tx based on peer's capabilities")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: implement callbacks for <add/mod/del>_link_station

Implement callbacks for cfg80211 add_link_station, mod_link_station,
and del_link_station API.

Signed-off-by: Shaul Triebitz <shaul.triebitz@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: Remove AP SMPS leftovers

AP SMPS was removed and not needed anymore. Remove the leftovers.

Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: keep recently active tx queues in scheduling list

This allows proper deficit accounting to ensure that they don't carry their
deficit until the next time they become active

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://lore.kernel.org/r/20220625212411.36675-4-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: make sta airtime deficit field s32 instead of s64

32 bit is more than enough range for the airtime deficit

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://lore.kernel.org/r/20220625212411.36675-2-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: switch airtime fairness back to deficit round-robin scheduling

This reverts commits 6a789ba679d652587532cec2a0e0274fda172f3b and
2433647bc8d983a543e7d31b41ca2de1c7e2c198.

The virtual time scheduler code has a number of issues:
- queues slowed down by hardware/firmware powersave handling were not properly
handled.
- on ath10k in push-pull mode, tx queues that the driver tries to pull from
were starved, causing excessive latency
- delay between tx enqueue and reported airtime use were causing excessively
bursty tx behavior

The bursty behavior may also be present on the round-robin scheduler, but there
it is much easier to fix without introducing additional regressions

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://lore.kernel.org/r/20220625212411.36675-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: sta_info: fix a missing kernel-doc struct element

struct link_sta_info has now a cur_max_bandwidth data:

net/mac80211/sta_info.h:569: warning: Function parameter or member 'cur_max_bandwidth' not described in 'link_sta_info'

Copy the meaning from struct sta_info, documenting it.

Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Link: https://lore.kernel.org/r/37d898634bb30776442a33833c48cbb21c90ecc6.1656409369.git.mchehab@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wifi: mac80211: maintain link-sta hash table

Maintain a hash table of link-sta addresses so we can find
them for management frames etc. where addresses haven't
been replaced by the drivers to the MLD address yet.

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

wifi: mac80211: RCU-ify link STA pointers

We need to be able to access these in a race-free way under
traffic while adding/removing them, so RCU-ify the pointers.
This requires passing a link_sta to a lot of functions so
we don't have to do the RCU handling everywhere.

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

wifi: mac80211: add sta link addition/removal

Add the necessary infrastructure, including a new driver
method, to add/remove links to/from a station. To do this,
refactor the link alloc/free a bit, splitting that so we
can do it without linking them, to handle failures better.

Note that a station entry must be created representing an
MLD or a non-MLD STA, it cannot change between the two.
When representing an MLD, the 'deflink' is used for the
first link, which might be removed later, in which case
the memory isn't reused.

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

wifi: mac80211: use IEEE80211_MLD_MAX_NUM_LINKS

Remove MAX_STA_LINKS and use IEEE80211_MLD_MAX_NUM_LINKS
instead to unify between the station and other data structures.

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

wifi: mac80211: remove sta_info_tx_streams()

The function is unused since commit 52b4810bed83 ("mac80211: Remove
support for changing AP SMPS mode") so we can just remove it.

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

wifi: mac80211: remove cipher scheme support

The only driver using this was iwlwifi, where we just removed
the support because it was never really used. Remove the code
from mac80211 as well.

Change-Id: I1667417a5932315ee9d81f5c233c56a354923f09
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: prepare sta handling for MLO support

Currently in mac80211 each STA object is represented
using sta_info datastructure with the associated
STA specific information and drivers access ieee80211_sta
part of it.

With MLO (Multi Link Operation) support being added
in 802.11be standard, though the association is logically
with a single Multi Link capable STA, at the physical level
communication can happen via different advertised
links (uniquely identified by Channel, operating class,
BSSID) and hence the need to handle multiple link
STA parameters within a composite sta_info object
called the MLD STA. The different link STA part of
MLD STA are identified using the link address which can
be same or different as the MLD STA address and unique
link id based on the link vif.

To support extension of such a model, the sta_info
datastructure is modified to hold multiple link STA
objects with link specific params currently within
sta_info moved to this new structure. Similarly this is
done for ieee80211_sta as well which will be accessed
within mac80211 as well as by drivers, hence trivial
driver changes are expected to support this.

For current non MLO supported drivers, only one link STA
is present and link information is accessed via 'deflink'
member.

For MLO drivers, we still need to define the APIs etc. to
get the correct link ID and access the correct part of
the station info.

Currently in mac80211, all link STA info are accessed directly
via deflink. These will be updated to access via link pointers
indexed by link id with MLO support patches, with link id
being 0 for non MLO supported cases.

Except for couple of macro related changes, below spatch takes
care of updating mac80211 and driver code to access to the
link STA info via deflink.

@ieee80211_sta@
struct ieee80211_sta *s;
struct sta_info *si;
identifier var = {supp_rates, ht_cap, vht_cap, he_cap, he_6ghz_capa, eht_cap, rx_nss, bandwidth, txpwr};
@@

(
s->
- var
+ deflink.var
|
si->sta.
- var
+ deflink.var
)

@sta_info@
struct sta_info *si;
identifier var = {gtk, pcpu_rx_stats, rx_stats, rx_stats_avg, status_stats, tx_stats, cur_max_bandwidth};
@@

(
si->
- var
+ deflink.var
)

Signed-off-by: Sriram R <quic_srirrama@quicinc.com>
Link: https://lore.kernel.org/r/1649086883-13246-1-git-send-email-quic_srirrama@quicinc.com
[remove MLO-drivers notes from commit message, not clear yet; run spatch]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add docs for ssn in struct tid_ampdu_tx

As pointed out by Stephen, add the missing docs.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Link: https://lore.kernel.org/r/20211129091948.1327ec82beab.Iecc5975406a3028d35c65ff8d2dec31a693888d3@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix regression in SSN handling of addba tx

Some drivers that do their own sequence number allocation (e.g. ath9k) rely
on being able to modify params->ssn on starting tx ampdu sessions.
This was broken by a change that modified it to use sta->tid_seq[tid] instead.

Cc: stable@vger.kernel.org
Fixes: 31d8bb4e07f8 ("mac80211: agg-tx: refactor sending addba")
Reported-by: Eneas U de Queiroz <cotequeiroz@gmail.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20211124094024.43222-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Switch to a virtual time-based airtime scheduler

This switches the airtime scheduler in mac80211 to use a virtual
time-based scheduler instead of the round-robin scheduler used before.
This has a couple of advantages:

- No need to sync up the round-robin scheduler in firmware/hardware with
the round-robin airtime scheduler.

- If several stations are eligible for transmission we can schedule both
of them; no need to hard-block the scheduling rotation until the head
of the queue has used up its quantum.

- The check of whether a station is eligible for transmission becomes
simpler (in ieee80211_txq_may_transmit()).

The drawback is that scheduling becomes slightly more expensive, as we
need to maintain an rbtree of TXQs sorted by virtual time. This means
that ieee80211_register_airtime() becomes O(logN) in the number of
currently scheduled TXQs because it can change the order of the
scheduled stations. We mitigate this overhead by only resorting when a
station changes position in the tree, and hopefully N rarely grows too
big (it's only TXQs currently backlogged, not all associated stations),
so it shouldn't be too big of an issue.

To prevent divisions in the fast path, we maintain both station sums and
pre-computed reciprocals of the sums. This turns the fast-path operation
into a multiplication, with divisions only happening as the number of
active stations change (to re-compute the current sum of all active
station weights). To prevent this re-computation of the reciprocal from
happening too frequently, we use a time-based notion of station
activity, instead of updating the weight every time a station gets
scheduled or de-scheduled. As queues can oscillate between empty and
occupied quite frequently, this can significantly cut down on the number
of re-computations. It also has the added benefit of making the station
airtime calculation independent on whether the queue happened to have
drained at the time an airtime value was accounted.

Co-developed-by: Yibo Zhao <yiboz@codeaurora.org>
Signed-off-by: Yibo Zhao <yiboz@codeaurora.org>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20210623134755.235545-1-toke@redhat.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: prevent attacks on TKIP/WEP as well

Similar to the issues fixed in previous patches, TKIP and WEP
should be protected even if for TKIP we have the Michael MIC
protecting it, and WEP is broken anyway.

However, this also somewhat protects potential other algorithms
that drivers might implement.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210511200110.430e8c202313.Ia37e4e5b6b3eaab1a5ae050e015f6c92859dbe27@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add fragment cache to sta_info

Prior patches protected against fragmentation cache attacks
by coloring keys, but this shows that it can lead to issues
when multiple stations use the same sequence number. Add a
fragment cache to struct sta_info (in addition to the one in
the interface) to separate fragments for different stations
properly.

This then automatically clear most of the fragment cache when a
station disconnects (or reassociates) from an AP, or when client
interfaces disconnect from the network, etc.

On the way, also fix the comment there since this brings us in line
with the recommendation in 802.11-2016 ("An AP should support ...").
Additionally, remove a useless condition (since there's no problem
purging an already empty list).

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20210511200110.fc35046b0d52.I1ef101e3784d13e8f6600d83de7ec9a3a45bcd52@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add rx decapsulation offload support

This allows drivers to pass 802.3 frames to mac80211, with some restrictions:

- the skb must be passed with a valid sta
- fast-rx needs to be active for the sta
- monitor mode needs to be disabled

mac80211 will tell the driver when it is safe to enable rx decap offload for
a particular station.

In order to implement support, a driver must:

- call ieee80211_hw_set(hw, SUPPORTS_RX_DECAP_OFFLOAD)
- implement ops->sta_set_decap_offload
- mark 802.3 frames with RX_FLAG_8023

If it doesn't want to enable offload for some vif types, it can mask out
IEEE80211_OFFLOAD_DECAP_ENABLED in vif->offload_flags from within the
.add_interface or .update_vif_offload driver ops

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20201218184718.93650-6-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix kernel-doc markups

Some identifiers have different names between their prototypes
and the kernel-doc markup.

Others need to be fixed, as kernel-doc markups should use this format:
identifier - description

In the specific case of __sta_info_flush(), add a documentation
for sta_info_flush(), as this one is the one used outside
sta_info.c.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Link: https://lore.kernel.org/r/978d35eef2dc76e21c81931804e4eaefbd6d635e.1603469755.git.mchehab+huawei@kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: initialize last_rate for S1G STAs

last_rate is initialized to zero by sta_info_alloc(), but
this indicates legacy bitrate for the last TX rate (and
invalid for the last RX rate). To avoid a warning when
decoding the last rate as legacy (before a data frame
has been sent), initialize them as S1G MCS.

Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
Link: https://lore.kernel.org/r/20201005164522.18069-2-thomas@adapt-ip.com
[rename to ieee80211_s1g_sta_rate_init(), seems more appropriate]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: optimize station connection monitor

Calling mod_timer for every rx/tx packet can be quite expensive.
Instead of constantly updating the timer, we can simply let it run out
and check the timestamp of the last ACK or rx packet to re-arm it.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20200908123702.88454-9-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: reduce packet loss event false positives

When running a large number of packets per second with a high data rate
and long A-MPDUs, the packet loss threshold can be reached very quickly
when the link conditions change. This frequently shows up as spurious
disconnects.
Mitigate false positives by using a similar logic for regular stations
as the one being used for TDLS, though with a more aggressive timeout.
Packet loss events are only reported if no ACK was received for a second.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20200808172542.41628-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: use rate provided via status->rate on ieee80211_tx_status_ext for AQL

Since ieee80211_tx_info does not have enough room to encode HE rates, HE
drivers use status->rate to provide rate info.
Store it in struct sta_info and use it for AQL.

Signed-off-by: Felix Fietkau <nbd@nbd.name>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20200821163045.62140-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

cfg80211/mac80211: add connected to auth server to station info

This patch adds the necessary bits to later query the auth server
flag for every peer from iw.

Signed-off-by: Markus Theil <markus.theil@tu-ilmenau.de>
Link: https://lore.kernel.org/r/20200611140238.427461-2-markus.theil@tu-ilmenau.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix two missing documentation entries

Add documentation for two struct entries that was missing.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://lore.kernel.org/r/20200424123945.6b23a26ab5e7.I664440ab5f33442df8103253bf5b9fe84be8d58c@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: agg-tx: add an option to defer ADDBA transmit

Driver tells mac80211 to sends ADDBA with SSN (starting sequence number)
from the head of the queue, while the transmission of all the frames in the
queue may take a while, which causes the peer to time out. In order to
fix this scenario, add an option to defer ADDBA transmit until queue
is drained.

Signed-off-by: Mordechay Goodstein <mordechay.goodstein@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200326150855.0f27423fec75.If67daab123a27c1cbddef000d6a3f212aa6309ef@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: drop data frames without key on encrypted links

If we know that we have an encrypted link (based on having had
a key configured for TX in the past) then drop all data frames
in the key selection handler if there's no key anymore.

This fixes an issue with mac80211 internal TXQs - there we can
buffer frames for an encrypted link, but then if the key is no
longer there when they're dequeued, the frames are sent without
encryption. This happens if a station is disconnected while the
frames are still on the TXQ.

Detecting that a link should be encrypted based on a first key
having been configured for TX is fine as there are no use cases
for a connection going from with encryption to no encryption.
With extended key IDs, however, there is a case of having a key
configured for only decryption, so we can't just trigger this
behaviour on a key being configured.

Cc: stable@vger.kernel.org
Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/iwlwifi.20200326150855.6865c7f28a14.I9fb1d911b064262d33e33dfba730cdeef83926ca@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Support BIGTK configuration for Beacon protection

Extend mac80211 key configuration to support the new BIGTK with key
index values 6 and 7. Support for actually protecting Beacon frames
(adding the MME in AP mode and checking it in STA mode) is covered in
separate commits.

Signed-off-by: Jouni Malinen <jouni@codeaurora.org>
Link: https://lore.kernel.org/r/20200222132548.20835-3-jouni@codeaurora.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Turn AQL into an NL80211_EXT_FEATURE

Instead of just having an airtime flag in debugfs, turn AQL into a proper
NL80211_EXT_FEATURE, so drivers can turn it on when they are ready, and so
we also expose the presence of the feature to userspace.

This also has the effect of flipping the default, so drivers have to opt in
to using AQL instead of getting it by default with TXQs. To keep
functionality the same as pre-patch, we set this feature for ath10k (which
is where it is needed the most).

While we're at it, split out the debugfs interface so AQL gets its own
per-station debugfs file instead of using the 'airtime' file.

[Johannes:]
This effectively disables AQL for iwlwifi, where it fixes a number of
issues:
* TSO in iwlwifi is causing underflows and associated warnings in AQL
* HE (802.11ax) rates aren't reported properly so at HE rates, AQL could
never have a valid estimate (it'd use 6 Mbps instead of up to 2400!)

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191212111437.224294-1-toke@redhat.com
Fixes: 3ace10f5b5ad ("mac80211: Implement Airtime-based Queue Limit (AQL)")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Implement Airtime-based Queue Limit (AQL)

In order for the Fq_CoDel algorithm integrated in mac80211 layer to operate
effectively to control excessive queueing latency, the CoDel algorithm
requires an accurate measure of how long packets stays in the queue, AKA
sojourn time. The sojourn time measured at the mac80211 layer doesn't
include queueing latency in the lower layer (firmware/hardware) and CoDel
expects lower layer to have a short queue. However, most 802.11ac chipsets
offload tasks such TX aggregation to firmware or hardware, thus have a deep
lower layer queue.

Without a mechanism to control the lower layer queue size, packets only
stay in mac80211 layer transiently before being sent to firmware queue.
As a result, the sojourn time measured by CoDel in the mac80211 layer is
almost always lower than the CoDel latency target, hence CoDel does little
to control the latency, even when the lower layer queue causes excessive
latency.

The Byte Queue Limits (BQL) mechanism is commonly used to address the
similar issue with wired network interface. However, this method cannot be
applied directly to the wireless network interface. "Bytes" is not a
suitable measure of queue depth in the wireless network, as the data rate
can vary dramatically from station to station in the same network, from a
few Mbps to over Gbps.

This patch implements an Airtime-based Queue Limit (AQL) to make CoDel work
effectively with wireless drivers that utilized firmware/hardware
offloading. AQL allows each txq to release just enough packets to the lower
layer to form 1-2 large aggregations to keep hardware fully utilized and
retains the rest of the frames in mac80211 layer to be controlled by the
CoDel algorithm.

Signed-off-by: Kan Yan <kyan@google.com>
[ Toke: Keep API to set pending airtime internal, fix nits in commit msg ]
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191119060610.76681-4-kyan@google.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Add new sta_info getter by sta/vif addrs

In ieee80211_tx_status() we don't have an sdata struct when looking up the
destination sta. Instead, we just do a lookup by the vif addr that is the
source of the packet being completed. Factor this out into a new sta_info
getter helper, since we need to use it for accounting AQL as well.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191112130835.382062-1-toke@redhat.com
[remove internal rcu_read_lock(), document instead]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add assoc-at support

Report timestamp for when sta becomes associated.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Link: https://lore.kernel.org/r/20190809180001.26393-2-greearb@candelatech.com
[fix ktime_get_boot_ns() to ktime_get_boottime_ns(), assoc_at type to u64]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

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>

mac80211: fix missing/malformed documentation

Fix the missing and malformed documentation that kernel-doc and
sphinx warn about. While at it, also add some things to the docs
to fix missing links.

Sadly, the only way I could find to fix this was to add some
trailing whitespace.

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

mac80211: Fix documentation strings for airtime-related variables

There was a typo in the documentation for weight_multiplier in mac80211.h,
and the doc was missing entirely for airtime and airtime_weight in sta_info.h.

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: mesh: use average bitrate for link metric calculation

Use bitrate moving average to smooth out link metric and stablize path
selection.

Signed-off-by: Julan Hsu <julanhsu@google.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Add airtime accounting and scheduling to TXQs

This adds airtime accounting and scheduling to the mac80211 TXQ
scheduler. A new callback, ieee80211_sta_register_airtime(), is added
that drivers can call to report airtime usage for stations.

When airtime information is present, mac80211 will schedule TXQs
(through ieee80211_next_txq()) in a way that enforces airtime fairness
between active stations. This scheduling works the same way as the ath9k
in-driver airtime fairness scheduling. If no airtime usage is reported
by the driver, the scheduler will default to round-robin scheduling.

For drivers that don't control TXQ scheduling in software, a new API
function, ieee80211_txq_may_transmit(), is added which the driver can use
to check if the TXQ is eligible for transmission, or should be throttled to
enforce fairness. Calls to this function must also be enclosed in
ieee80211_txq_schedule_{start,end}() calls to ensure proper locking.

The API ieee80211_txq_may_transmit() also ensures that TXQ list will be
aligned aginst driver's own round-robin scheduler list. i.e it rotates
the TXQ list till it makes the requested node becomes the first entry
in TXQ list. Thus both the TXQ list and driver's list are in sync.

Co-developed-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
Signed-off-by: Louie Lu <git@louie.lu>
[added debugfs write op to reset airtime counter]
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

{nl,mac}80211: report gate connectivity in station info

Capture the current state of gate connectivity from the mesh
formation field in mesh config whenever we receive a beacon,
and report that via GET_STATION. This allows applications
doing mesh peering in userspace to make peering decisions
based on peers' current upstream connectivity.

Signed-off-by: Bob Copeland <bobcopeland@fb.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add support for HE

Add support for HE in mac80211 conforming with P802.11ax_D1.4.

Johannes: Fix another bug with the buf_size comparison in agg-rx.c.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Ido Yariv <idox.yariv@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: allocate and fill tidstats only when needed

This fixes memory leaks in the case where we just have the
station info on the stack for internal usage without sending
it to cfg80211.

Fixes: 8689c051a201 ("cfg80211: dynamically allocate per-tid stats for station info")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: average ack rssi support for data frames

The driver will process the RSSI if available and send it to mac80211.
mac80211 will compute the weighted average of ack RSSI for stations.

Signed-off-by: Balaji Pothunoori <bpothuno@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Add tx ack signal support in sta info

This allows users to get ack signal strength of
last transmitted frame.

Signed-off-by: Venkateswara Naralasetty <vnaralas@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Revert "mac80211: Add airtime account and scheduling to TXQs"

This reverts commit b0d52ad821843a6c5badebd80feef9f871904fa6.

We need to revert the TXQ scheduling API due to conflicts
with a new driver, and this depends on that API.

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

mac80211: Add airtime account and scheduling to TXQs

This adds airtime accounting and scheduling to the mac80211 TXQ
scheduler. A new hardware flag, AIRTIME_ACCOUNTING, is added that
drivers can set if they support reporting airtime usage of
transmissions. When this flag is set, mac80211 will expect the actual
airtime usage to be reported in the tx_time and rx_time fields of the
respective status structs.

When airtime information is present, mac80211 will schedule TXQs
(through ieee80211_next_txq()) in a way that enforces airtime fairness
between active stations. This scheduling works the same way as the ath9k
in-driver airtime fairness scheduling.

Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: aggregation: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly.

This removes the tid mapping array and expands the tid structures to
add a pointer back to the station, along with the tid index itself.

Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
[switch tid variables to u8, the valid range is 0-15 at most,
initialize tid_tx->sta/tid properly]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/mesh_plink: Convert timers to use timer_setup()

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. This requires adding a pointer back
to the sta_info since container_of() can't resolve the sta_info.

Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix STA_SLOW_THRESHOLD htmldocs failure

Patch fixes htmldocs build problem:

Error(.//net/mac80211/sta_info.h:416): cannot understand prototype: 'STA_SLOW_THRESHOLD 6000 '

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: manage RX BA session offload without SKB queue

Instead of using the SKB queue with the fake pkt_type for the
offloaded RX BA session management, also handle this with the
normal aggregation state machine worker. This also makes the
use of this more reliable since it gets rid of the allocation
of the fake skb.

Combined with the previous patch, this finally allows us to
get rid of the pkt_type hack entirely, so do that as well.

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

mac80211: fix TX aggregation start/stop callback race

When starting or stopping an aggregation session, one of the steps
is that the driver calls back to mac80211 that the start/stop can
proceed. This is handled by queueing up a fake SKB and processing
it from the normal iface/sdata work. Since this isn't flushed when
disassociating, the following race is possible:

* associate
* start aggregation session
* driver callback
* disassociate
* associate again to the same AP
* callback processing runs, leading to a WARN_ON() that
the TID hadn't requested aggregation

If the second association isn't to the same AP, there would only
be a message printed ("Could not find station: <addr>"), but the
same race could happen.

Fix this by not going the whole detour with a fake SKB etc. but
simply looking up the aggregation session in the driver callback,
marking it with a START_CB/STOP_CB bit and then scheduling the
regular aggregation work that will now process these bits as well.
This also simplifies the code and gets rid of the whole problem
with allocation failures of said skb, which could have left the
session in limbo.

Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

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>

mac80211: use bitfield macros for encoded rate

Instead of hand-coding the bit manipulations, use the bitfield
macros to generate the code for the encoded bitrate.

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

mac80211: rename ieee80211_rx_status::vht_nss to just nss

This field will need to be used again for HE, so rename it now.

Again, mostly done with this spatch:

@@
expression status;
@@
-status->vht_nss
+status->nss
@@
expression status;
@@
-status.vht_nss
+status.nss

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

mac80211: separate encoding/bandwidth from flags

We currently use a lot of flags that are mutually incompatible,
separate this out into actual encoding and bandwidth enum values.

Much of this again done with spatch, with manual post-editing,
mostly to add the switch statements and get rid of the conversions.

@@
expression status;
@@
-status->enc_flags |= RX_ENC_FLAG_80MHZ
+status->bw = RATE_INFO_BW_80
@@
expression status;
@@
-status->enc_flags |= RX_ENC_FLAG_40MHZ
+status->bw = RATE_INFO_BW_40
@@
expression status;
@@
-status->enc_flags |= RX_ENC_FLAG_20MHZ
+status->bw = RATE_INFO_BW_20
@@
expression status;
@@
-status->enc_flags |= RX_ENC_FLAG_160MHZ
+status->bw = RATE_INFO_BW_160
@@
expression status;
@@
-status->enc_flags |= RX_ENC_FLAG_5MHZ
+status->bw = RATE_INFO_BW_5
@@
expression status;
@@
-status->enc_flags |= RX_ENC_FLAG_10MHZ
+status->bw = RATE_INFO_BW_10

@@
expression status;
@@
-status->enc_flags |= RX_ENC_FLAG_VHT
+status->encoding = RX_ENC_VHT
@@
expression status;
@@
-status->enc_flags |= RX_ENC_FLAG_HT
+status->encoding = RX_ENC_HT
@@
expression status;
@@
-status.enc_flags |= RX_ENC_FLAG_VHT
+status.encoding = RX_ENC_VHT
@@
expression status;
@@
-status.enc_flags |= RX_ENC_FLAG_HT
+status.encoding = RX_ENC_HT

@@
expression status;
@@
-(status->enc_flags & RX_ENC_FLAG_HT)
+(status->encoding == RX_ENC_HT)
@@
expression status;
@@
-(status->enc_flags & RX_ENC_FLAG_VHT)
+(status->encoding == RX_ENC_VHT)

@@
expression status;
@@
-(status->enc_flags & RX_ENC_FLAG_5MHZ)
+(status->bw == RATE_INFO_BW_5)
@@
expression status;
@@
-(status->enc_flags & RX_ENC_FLAG_10MHZ)
+(status->bw == RATE_INFO_BW_10)
@@
expression status;
@@
-(status->enc_flags & RX_ENC_FLAG_40MHZ)
+(status->bw == RATE_INFO_BW_40)
@@
expression status;
@@
-(status->enc_flags & RX_ENC_FLAG_80MHZ)
+(status->bw == RATE_INFO_BW_80)
@@
expression status;
@@
-(status->enc_flags & RX_ENC_FLAG_160MHZ)
+(status->bw == RATE_INFO_BW_160)

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

mac80211: clean up rate encoding bits in RX status

In preparation for adding support for HE rates, clean up
the driver report encoding for rate/bandwidth reporting
on RX frames.

Much of this patch was done with the following spatch:

@@
expression status;
@@
-status->flag & (RX_FLAG_HT | RX_FLAG_VHT)
+status->enc_flags & (RX_ENC_FLAG_HT | RX_ENC_FLAG_VHT)

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_SHORTPRE
+status->enc_flags op RX_ENC_FLAG_SHORTPRE
@@
expression status;
@@
-status->flag & RX_FLAG_SHORTPRE
+status->enc_flags & RX_ENC_FLAG_SHORTPRE

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_HT
+status->enc_flags op RX_ENC_FLAG_HT
@@
expression status;
@@
-status->flag & RX_FLAG_HT
+status->enc_flags & RX_ENC_FLAG_HT

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_40MHZ
+status->enc_flags op RX_ENC_FLAG_40MHZ
@@
expression status;
@@
-status->flag & RX_FLAG_40MHZ
+status->enc_flags & RX_ENC_FLAG_40MHZ

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_SHORT_GI
+status->enc_flags op RX_ENC_FLAG_SHORT_GI
@@
expression status;
@@
-status->flag & RX_FLAG_SHORT_GI
+status->enc_flags & RX_ENC_FLAG_SHORT_GI

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_HT_GF
+status->enc_flags op RX_ENC_FLAG_HT_GF
@@
expression status;
@@
-status->flag & RX_FLAG_HT_GF
+status->enc_flags & RX_ENC_FLAG_HT_GF

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_VHT
+status->enc_flags op RX_ENC_FLAG_VHT
@@
expression status;
@@
-status->flag & RX_FLAG_VHT
+status->enc_flags & RX_ENC_FLAG_VHT

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_STBC_MASK
+status->enc_flags op RX_ENC_FLAG_STBC_MASK
@@
expression status;
@@
-status->flag & RX_FLAG_STBC_MASK
+status->enc_flags & RX_ENC_FLAG_STBC_MASK

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_LDPC
+status->enc_flags op RX_ENC_FLAG_LDPC
@@
expression status;
@@
-status->flag & RX_FLAG_LDPC
+status->enc_flags & RX_ENC_FLAG_LDPC

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_10MHZ
+status->enc_flags op RX_ENC_FLAG_10MHZ
@@
expression status;
@@
-status->flag & RX_FLAG_10MHZ
+status->enc_flags & RX_ENC_FLAG_10MHZ

@@
assignment operator op;
expression status;
@@
-status->flag op RX_FLAG_5MHZ
+status->enc_flags op RX_ENC_FLAG_5MHZ
@@
expression status;
@@
-status->flag & RX_FLAG_5MHZ
+status->enc_flags & RX_ENC_FLAG_5MHZ

@@
assignment operator op;
expression status;
@@
-status->vht_flag op RX_VHT_FLAG_80MHZ
+status->enc_flags op RX_ENC_FLAG_80MHZ
@@
expression status;
@@
-status->vht_flag & RX_VHT_FLAG_80MHZ
+status->enc_flags & RX_ENC_FLAG_80MHZ

@@
assignment operator op;
expression status;
@@
-status->vht_flag op RX_VHT_FLAG_160MHZ
+status->enc_flags op RX_ENC_FLAG_160MHZ
@@
expression status;
@@
-status->vht_flag & RX_VHT_FLAG_160MHZ
+status->enc_flags & RX_ENC_FLAG_160MHZ

@@
assignment operator op;
expression status;
@@
-status->vht_flag op RX_VHT_FLAG_BF
+status->enc_flags op RX_ENC_FLAG_BF
@@
expression status;
@@
-status->vht_flag & RX_VHT_FLAG_BF
+status->enc_flags & RX_ENC_FLAG_BF

@@
assignment operator op;
expression status, STBC;
@@
-status->flag op STBC << RX_FLAG_STBC_SHIFT
+status->enc_flags op STBC << RX_ENC_FLAG_STBC_SHIFT

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_SHORTPRE
+status.enc_flags op RX_ENC_FLAG_SHORTPRE
@@
expression status;
@@
-status.flag & RX_FLAG_SHORTPRE
+status.enc_flags & RX_ENC_FLAG_SHORTPRE

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_HT
+status.enc_flags op RX_ENC_FLAG_HT
@@
expression status;
@@
-status.flag & RX_FLAG_HT
+status.enc_flags & RX_ENC_FLAG_HT

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_40MHZ
+status.enc_flags op RX_ENC_FLAG_40MHZ
@@
expression status;
@@
-status.flag & RX_FLAG_40MHZ
+status.enc_flags & RX_ENC_FLAG_40MHZ

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_SHORT_GI
+status.enc_flags op RX_ENC_FLAG_SHORT_GI
@@
expression status;
@@
-status.flag & RX_FLAG_SHORT_GI
+status.enc_flags & RX_ENC_FLAG_SHORT_GI

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_HT_GF
+status.enc_flags op RX_ENC_FLAG_HT_GF
@@
expression status;
@@
-status.flag & RX_FLAG_HT_GF
+status.enc_flags & RX_ENC_FLAG_HT_GF

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_VHT
+status.enc_flags op RX_ENC_FLAG_VHT
@@
expression status;
@@
-status.flag & RX_FLAG_VHT
+status.enc_flags & RX_ENC_FLAG_VHT

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_STBC_MASK
+status.enc_flags op RX_ENC_FLAG_STBC_MASK
@@
expression status;
@@
-status.flag & RX_FLAG_STBC_MASK
+status.enc_flags & RX_ENC_FLAG_STBC_MASK

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_LDPC
+status.enc_flags op RX_ENC_FLAG_LDPC
@@
expression status;
@@
-status.flag & RX_FLAG_LDPC
+status.enc_flags & RX_ENC_FLAG_LDPC

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_10MHZ
+status.enc_flags op RX_ENC_FLAG_10MHZ
@@
expression status;
@@
-status.flag & RX_FLAG_10MHZ
+status.enc_flags & RX_ENC_FLAG_10MHZ

@@
assignment operator op;
expression status;
@@
-status.flag op RX_FLAG_5MHZ
+status.enc_flags op RX_ENC_FLAG_5MHZ
@@
expression status;
@@
-status.flag & RX_FLAG_5MHZ
+status.enc_flags & RX_ENC_FLAG_5MHZ

@@
assignment operator op;
expression status;
@@
-status.vht_flag op RX_VHT_FLAG_80MHZ
+status.enc_flags op RX_ENC_FLAG_80MHZ
@@
expression status;
@@
-status.vht_flag & RX_VHT_FLAG_80MHZ
+status.enc_flags & RX_ENC_FLAG_80MHZ

@@
assignment operator op;
expression status;
@@
-status.vht_flag op RX_VHT_FLAG_160MHZ
+status.enc_flags op RX_ENC_FLAG_160MHZ
@@
expression status;
@@
-status.vht_flag & RX_VHT_FLAG_160MHZ
+status.enc_flags & RX_ENC_FLAG_160MHZ

@@
assignment operator op;
expression status;
@@
-status.vht_flag op RX_VHT_FLAG_BF
+status.enc_flags op RX_ENC_FLAG_BF
@@
expression status;
@@
-status.vht_flag & RX_VHT_FLAG_BF
+status.enc_flags & RX_ENC_FLAG_BF

@@
assignment operator op;
expression status, STBC;
@@
-status.flag op STBC << RX_FLAG_STBC_SHIFT
+status.enc_flags op STBC << RX_ENC_FLAG_STBC_SHIFT

@@
@@
-RX_FLAG_STBC_SHIFT
+RX_ENC_FLAG_STBC_SHIFT

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

mac80211: encode rate type (legacy, HT, VHT) with fewer bits

We don't really need three different bits for each, since the
types are mutually exclusive. Use just two bits for it.

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

mac80211: use DECLARE_EWMA for mesh_fail_avg

As moving average is not considering fractional part, it will
get stuck at the same level after certain state. For example,
with current values, it can get stuck at 96. Fortunately the
current threshold 95%, but if it were increased to 96 or more
mesh paths would never be deactivated. Fix failure average
movement by using EWMA helpers, which does take into account
fractional parts.

Signed-off-by: Rajkumar Manoharan <rmanohar@qca.qualcomm.com>
[johannes: pick a larger EWMA factor for more precision with
the limited range that we will feed into it, adjust to new API]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

average: change to declare precision, not factor

Declaring the factor is counter-intuitive, and people are prone
to using small(-ish) values even when that makes no sense.

Change the DECLARE_EWMA() macro to take the fractional precision,
in bits, rather than a factor, and update all users.

While at it, add some more documentation.

Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: don't reorder frames with SN smaller than SSN

When RX aggregation starts, transmitter may continue send frames
with SN smaller than SSN until the AddBA response is received.
However, the reorder buffer is already initialized at this point,
which will cause the drop of such frames as duplicates since the
head SN of the reorder buffer is set to the SSN, which is bigger.

Cc: stable@vger.kernel.org
Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix tid_agg_rx NULL dereference

On drivers setting the SUPPORTS_REORDERING_BUFFER hardware flag,
we crash when the peer sends an AddBA request while we already
have a session open on the seame TID; this is because on those
drivers, the tid_agg_rx is left NULL even though the session is
valid, and the agg_session_valid bit is set.

To fix this, store the dialog tokens outside the tid_agg_rx to
be able to compare them to the received AddBA request.

Fixes: f89e07d4cf26 ("mac80211: agg-rx: refuse ADDBA Request with timeout update")
Reported-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Use rhltable instead of rhashtable

mac80211 currently uses rhashtable with insecure_elasticity set
to true. The latter is because of duplicate objects. What's
more, mac80211 walks the rhashtable chains by hand which is broken
as rhashtable may contain multiple tables due to resizing or
rehashing.

This patch fixes it by converting it to the newly added rhltable
interface which is designed for use with duplicate objects.

With rhltable a lookup returns a list of objects instead of a
single one. This is then fed into the existing for_each_sta_info
macro.

This patch also deletes the sta_addr_hash function since rhashtable
defaults to jhash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

mac80211: send delBA on unexpected BlockAck data frames

When we receive data frames with ACK policy BlockAck, send
delBA as requested by the 802.11 spec. Since this would be
happening for every frame inside an A-MPDU if it's really
received outside a session, limit it to a single attempt.

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

mac80211: mesh: Add support for HW RC implementation

Mesh HWMP module will be able to rely on the HW
RC algorithm if it exists, for path metric calculations.

This allows the metric calculation mechanism to calculate
a correct metric, based on PER and last TX rate both via
HW RC algorithm if it exists or via parameters collected
by the SW.

Signed-off-by: Maxim Altshul <maxim.altshul@ti.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix fast_tx header alignment

The header field is defined as u8[] but also accessed as struct
ieee80211_hdr. Enforce an alignment of 2 to prevent unnecessary
unaligned accesses, which can be very harmful for performance on many
platforms.

Fixes: e495c24731a2 ("mac80211: extend fast-xmit for more ciphers")
Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: enable collecting station statistics per-CPU

If the driver advertises the new HW flag USE_RSS, make the
station statistics on the fast-rx path per-CPU. This will
enable calling the RX in parallel, only hitting locking or
shared cachelines when the fast-RX path isn't available.

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

mac80211: add fast-rx path

The regular RX path has a lot of code, but with a few
assumptions on the hardware it's possible to reduce the
amount of code significantly. Currently the assumptions
on the driver are the following:
* hardware/driver reordering buffer (if supporting aggregation)
* hardware/driver decryption & PN checking (if using encryption)
* hardware/driver did de-duplication
* hardware/driver did A-MSDU deaggregation
* AP_LINK_PS is used (in AP mode)
* no client powersave handling in mac80211 (in client mode)

of which some are actually checked per packet:
* de-duplication
* PN checking
* decryption
and additionally packets must
* not be A-MSDU (have been deaggregated by driver/device)
* be data packets
* not be fragmented
* be unicast
* have RFC 1042 header

Additionally dynamically we assume:
* no encryption or CCMP/GCMP, TKIP/WEP/other not allowed
* station must be authorized
* 4-addr format not enabled

Some data needed for the RX path is cached in a new per-station
"fast_rx" structure, so that we only need to look at this and
the packet, no other memory when processing packets on the fast
RX path.

After doing the above per-packet checks, the data path collapses
down to a pretty simple conversion function taking advantage of
the data cached in the small fast_rx struct.

This should speed up the RX processing, and will make it easier
to reason about parallelizing RX (for which statistics will need
to be per-CPU still.)

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

mac80211: fix RX u64 stats consistency on 32-bit platforms

On 32-bit platforms, the 64-bit counters we keep need to be protected
to be consistently read. Use the u64_stats_sync mechanism to do that.

In order to not end up with overly long lines, refactor the tidstats
assignments a bit.

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

mac80211: fix last RX rate data consistency

When storing the last_rate_* values in the RX code, there's nothing
to guarantee consistency, so a concurrent reader could see, e.g.
last_rate_idx on the new value, but last_rate_flag still on the old,
getting completely bogus values in the end.

To fix this, I lifted the sta_stats_encode_rate() function from my
old rate statistics code, which encodes the entire rate data into a
single 16-bit value, avoiding the consistency issue.

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

mac80211: add separate last_ack variable

Instead of touching the rx_stats.last_rx from the status path, introduce
and use a status_stats.last_ack variable. This will make rx_stats.last_rx
indicate when the last frame was received, making it available for real
"last_rx" and statistics gathering; statistics, when done per-CPU, will
need to figure out which place was updated last for those items where the
"last" value is exposed.

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

mac80211: move averaged values out of rx_stats

Move the averaged values out of rx_stats and into rx_stats_avg,
to cleanly split them out. The averaged ones cannot be supported
for parallel RX in a per-CPU fashion, while the other values can
be collected per CPU and then combined/selected when needed.

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

mac80211: clean up station flags debugfs

Avoid the really strange %s%s%s expression, use an array
of flag names and check that all flags are present.

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

mac80211: remove sta_info debugfs sub-struct

Since the previous patch, the struct only has a single member,
so remove the struct and leave just the single member.

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

mac80211: Remove unused variable in per STA debugfs struct

Remove unused variable in per STA debugfs structure, 'commit 34e895075e21
("mac80211: allow station add/remove to sleep")' removed the only user of
'add_has_run'.

Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: remove description of dropped member

Commit 976bd9efdae6 ("mac80211: move beacon_loss_count into ifmgd")
removed the member from the sta_info struct but the description stayed
lingering. Remove it.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add API to allow filtering frames in BA sessions

If any frames are dropped that are part of a BA session, the reorder
buffer will "indefinitely" (until the timeout) wait for them to come
in (or a BAR moving the window) and won't release frames after them.
This means it isn't possible to filter frames within a BA session in
firmware.

Introduce an API function that allows such filtering. Calling this
function will move the BA window forward to the new SSN, and allows
marking frames after the SSN as having been filtered, so any future
reordering activity will release frames while skipping the holes.

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

mac80211: support hw managing reorder logic

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

mac80211: add atomic uploaded keys iterator

add ieee80211_iter_keys_rcu() to iterate over uploaded
keys in atomic context (when rcu is locked)

The station removal code removes the keys only after
calling synchronize_net(), so it's not safe to iterate
the keys at this point (and postponing the actual key
deletion with call_rcu() might result in some
badly-ordered ops calls).

Add a flag to indicate a station is being removed,
and skip the configured keys if it's set.

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

mac80211: move station statistics into sub-structs

Group station statistics by where they're (mostly) updated
(TX, RX and TX-status) and group them into sub-structs of
the struct sta_info.

Also rename the variables since the grouping now makes it
obvious where they belong.

This makes it easier to identify where the statistics are
updated in the code, and thus easier to think about them.

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

mac80211: move beacon_loss_count into ifmgd

There's little point in keeping (and even sending to userspace)
the beacon_loss_count value per station, since it can only apply
to the AP on a managed-mode connection. Move the value to ifmgd,
advertise it only in managed mode, and remove it from ethtool as
it's available through better interfaces.

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

mac80211: remove sta->last_ack_signal

This file only feeds a debugfs file that isn't very useful, so remove
it. If necessary, we can add other ways to get this information, for
example in the NL80211_CMD_PROBE_CLIENT response.

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

mac80211: move sta_set_rate_info_rx() and make it static

There's only a single caller of this function, so it can
be moved to the same file and made static.

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

mac80211: allow to transmit A-MSDU within A-MPDU

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

mac80211: use DECLARE_EWMA

Instead of using the out-of-line average calculation, use the new
DECLARE_EWMA() macro to declare a signal EWMA, and use that.

This actually *reduces* the code size slightly (on x86-64) while
also reducing the station info size by 80 bytes.

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

mac80211: mesh: separate plid and aid concepts

According to 802.11-2012 13.3.1, a mesh STA should assign an AID
upon receipt of a mesh peering open frame rather than using the link
id of the peer. Using the peer link id has two potential issues:
it may not be unique among the peers, and by its nature it is random,
so the TIM may not compress well.

In preparation for allocating it properly, use sta->sta.aid, but keep
the existing behavior of using the plid in the aid we send.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: mesh: move fail_avg into mesh struct

This value is only used in mesh, so move it into the new mesh
sub-struct of the station info.

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

mac80211: upgrade BW of TDLS peers when possible

Define a station chandef, to be used for wider-bw TDLS peers. When both
peers support the feature, upgrade the channel bandwidth to the maximum
allowed by both peers and regulatory. Currently widths up to 80MHz are
supported in the 5GHz band.

When a TDLS peer connects/disconnects recalculate the channel type of the
current chanctx.
Make the chanctx width calculation consider wider-bw TDLS peers and
similarly fix the max_required_bw calculation for the chanctx min_def.
Since the sta->bandwidth is calculated only later on, take
bss_conf.chandef.width as the minimal width for station interface.

Set the upgraded channel width in the VHT-operation set during TDLS setup.

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

mac80211: define TDLS wider BW support bits

Allow a device to specify support for the TDLS wider-bandwidth feature.
Indicate this support during TDLS setup in the ext-capab IE and set an
appropriate station flag when our TDLS peer supports it.
This feature gives TDLS peers the ability to use a wider channel than
the base width of the BSS. For instance VHT capable TDLS peers connected
on a 20MHz channel can extend the channel to 80MHz, if regulatory
considerations allow it.

Do not cap the bandwidth of such stations by the current BSS channel width
in mac80211.

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

mac80211: move mesh related station fields to own struct

There are now a fairly large number of mesh fields that really
aren't needed in any other modes; move those into their own
structure and allocate them separately.

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

mac80211: duplicate station's MAC address for hash table

Currently, the station hash table lookup (or iteration) must
access two cachelines for each station - the one with the hash
table node, and the one with the MAC address.

Duplicate the MAC address next to the hash node to get rid of
this. Since the MAC address is static there's no consistency
problem introduced by this.

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

mac80211: fix comment referring to RX queue

There are no RX queues in mac80211 (yet), the comment should refer
to the TID (including one slot for non-QoS) rather than 'RX queue'.

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

mac80211: remove sta_info.gtk_idx

This struct member is only assigned, never used otherwise;
remove it.

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

mac80211: Always check rates and capabilities in mesh mode

In mesh mode there is a race between establishing links and processing
rates and capabilities in beacons. This is very noticeable with slow
beacons (e.g. beacon intervals of 1s) and manifested for us as stations
using minstrel when minstrel_ht should be used. Fixed by changing
mesh_sta_info_init so that it always checks rates and such if it has not
already done so.

Signed-off-by: Alexis Green <agreen@cococorp.com>
CC: Jesse Jones <jjones@cococorp.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add missing documentation for rate_ctrl_lock

This was missed in the previous patch, add some documentation
for rate_ctrl_lock to avoid docbook warnings.

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

mac80211: remove sta->tx_fragments counter

This counter is unsafe with concurrent TX and is only exposed
through debugfs and ethtool. Instead of trying to fix it just
remove it for now, if it's really needed then it should be
exposed through nl80211 and in a way that drivers that do the
fragmentation in the device could support it as well.

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

mac80211: extend fast-xmit for more ciphers

When crypto is offloaded then in some cases it's all handled
by the device, and in others only some space for the IV must
be reserved in the frame. Handle both of these cases in the
fast-xmit path, up to a limit of 18 bytes of space for IVs.

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

mac80211: add TX fastpath

In order to speed up mac80211's TX path, add the "fast-xmit" cache
that will cache the data frame 802.11 header and other data to be
able to build the frame more quickly. This cache is rebuilt when
external triggers imply changes, but a lot of the checks done per
packet today are simplified away to the check for the cache.

There's also a more detailed description in the code.

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

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>

mac80211: introduce plink lock for plink fields

The mesh plink code uses sta->lock to serialize access to the
plink state fields between the peer link state machine and the
peer link timer. Some paths (e.g. those involving
mps_qos_null_tx()) unfortunately hold this spinlock across
frame tx, which is soon to be disallowed. Add a new spinlock
just for plink access.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add an intermediate software queue implementation

This allows drivers to request per-vif and per-sta-tid queues from which
they can pull frames. This makes it easier to keep the hardware queues
short, and to improve fairness between clients and vifs.

The task of scheduling packet transmission is left up to the driver -
queueing is controlled by mac80211. Drivers can only dequeue packets by
calling ieee80211_tx_dequeue. This makes it possible to add active queue
management later without changing drivers using this code.

This can also be used as a starting point to implement A-MSDU
aggregation in a way that does not add artificially induced latency.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[resolved minor context conflict, minor changes, endian annotations]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix RX A-MPDU session reorder timer deletion

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: Johannes Berg <johannes.berg@intel.com>

mac80211: use rhashtable for station table

We currently have a hand-rolled table with 256 entries and are
using the last byte of the MAC address as the hash. This hash
is obviously very fast, but collisions are easily created and
we waste a lot of space in the common case of just connecting
as a client to an AP where we just have a single station. The
other common case of an AP is also suboptimal due to the size
of the hash table and the ease of causing collisions.

Convert all of this to use rhashtable with jhash, which gives
us the advantage of a far better hash function (with random
perturbation to avoid hash collision attacks) and of course
that the hash table grows and shrinks dynamically with chain
length, improving both cases above.

Use a specialised hash function (using jhash, but with fixed
length) to achieve better compiler optimisation as suggested
by Sergey Ryazanov.

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

mac80211: remove TX latency measurement code

Revert commit ad38bfc916da ("mac80211: Tx frame latency statistics")
(along with some follow-up fixes).

This code turned out not to be as useful in the current form as we
thought, and we've internally hacked it up more, but that's not
very suitable for upstream (for now), and we might just do that
with tracing instead.

Therefore, for now at least, remove this code. We might also need
to use the skb->tstamp field for the TCP performance issue, which
is more important than the debugging.

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

mac80211: provide per-TID RX/TX MSDU counters

Implement the new counters cfg80211 can now advertise to userspace.
The TX code is in the sequence number handler, which is a bit odd,
but that place already knows the TID and frame type, so it was
easiest and least impact there.

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

mac80211: synchronously reserve TID per station

In TDLS (e.g., TDLS off-channel) there is a requirement for
some drivers to supply an unused TID between the AP and the
device to the FW, to allow sending PTI requests and to allow
the FW to aggregate on a specific TID for better throughput.

To ensure that the allocated TID is indeed unused, this patch
introduces an API for blocking the driver from TXing on that
TID.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: introduce TDLS channel switch ops

Implement the cfg80211 TDLS channel switch ops and introduce new mac80211
ones for low-level drivers.
Verify low-level driver support for the new ops when using the relevant
wiphy feature bit. Also verify the peer supports channel switching before
passing the command down.

Add a new STA flag to track the off-channel state with the TDLS peer and
make sure to cancel the channel-switch if the peer STA is unexpectedly
removed.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: track AP and peer STA TDLS chan-switch support

The AP or peer can prohibit TDLS channel switch via a bit in the
extended capabilities IE. Parse the IE and track this bit. Set an
appropriate STA flag if both the AP and peer STA support TDLS
channel-switching.

Add the new STA flag and the missing TDLS_INITIATOR to debugfs.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix warning on htmldocs for last_tdls_pkt_time

Forgot to add an entry to the struct description of sta_info.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add TDLS connection timeout

Adding a timeout for tearing down a TDLS connection that
hasn't had ACKed traffic sent through it for a certain
amount of time.

Since we have no other monitoring facility to indicate the
existance (or non-existance) of a peer, this patch will
cause a peer to be considered as unavailable if for some X
time at least some Y packets have all not been ACKed.

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

mac80211: add Intel Mobile Communications copyright

Our legal structure changed at some point (see wikipedia), but
we forgot to immediately switch over to the new copyright
notice.

For files that we have modified in the time since the change,
add the proper copyright notice now.

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>

mac80211: fix offloaded BA session traffic after hw restart

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: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: don't duplicate station QoS capability data

We currently track the QoS capability twice: for all peer stations
in the WLAN_STA_WME flag, and for any clients associated to an AP
interface separately for drivers in the sta->sta.wme field.

Remove the WLAN_STA_WME flag and track the capability only in the
driver-visible field, getting rid of the limitation that the field
is only valid in AP mode.

Reviewed-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix Rx reordering with RX_FLAG_AMSDU_MORE

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: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: track TDLS initiator internally

Infer the TDLS initiator and track it in mac80211 via a STA flag. This
avoids breaking old userspace that doesn't pass it via nl80211 APIs.

The only case where userspace will need to pass the initiator is when the
STA is removed due to unreachability before a teardown packet is sent.
Support for unreachability was only recently added to wpa_supplicant, so
it won't be a problem in practice.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

cfg80211: make ethtool the driver's responsibility

Currently, cfg80211 tries to implement ethtool, but that doesn't
really scale well, with all the different operations. Make the
lower-level driver responsible for it, which currently only has
an effect on mac80211. It will similarly not scale well at that
level though, since mac80211 also has many drivers.

To cleanly implement this in mac80211, introduce a new file and
move some code to appropriate places.

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

mac80211: remove weak WEP IV accounting

Since WEP is practically dead, there seems very little
point in keeping WEP weak IV accounting.

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

mac80211: remove ignore_plink_timer flag

The mesh_plink code is doing some interesting things with the
ignore_plink_timer flag. It seems the original intent was to
handle this race:

cpu 0 cpu 1
----- -----
start timer handler for state X
acquire sta_lock
change state from X to Y
mod_timer() / del_timer()
release sta_lock
acquire sta_lock
execute state Y timer too soon

However, using the mod_timer()/del_timer() return values to
detect these cases is broken. As a result, timers get ignored
unnecessarily, and stations can get stuck in the peering state
machine.

Instead, we can detect the case by looking at the timer expiration.
In the case of del_timer, just ignore the timers in the following
(LISTEN/ESTAB) states since they won't have timers anyway.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix station/driver powersave race

It is currently possible to have a race due to the station PS
unblock work like this:
* station goes to sleep with frames buffered in the driver
* driver blocks wakeup
* station wakes up again
* driver flushes/returns frames, and unblocks, which schedules
the unblock work
* unblock work starts to run, and checks that the station is
awake (i.e. that the WLAN_STA_PS_STA flag isn't set)
* we process a received frame with PM=1, setting the flag again
* ieee80211_sta_ps_deliver_wakeup() runs, delivering all frames
to the driver, and then clearing the WLAN_STA_PS_DRIVER and
WLAN_STA_PS_STA flags

In this scenario, mac80211 will think that the station is awake,
while it really is asleep, and any TX'ed frames should be filtered
by the device (it will know that the station is sleeping) but then
passed to mac80211 again, which will not buffer it either as it
thinks the station is awake, and eventually the packets will be
dropped.

Fix this by moving the clearing of the flags to exactly where we
learn about the situation. This creates a problem of reordering,
so introduce another flag indicating that delivery is being done,
this new flag also queues frames and is cleared only while the
spinlock is held (which the queuing code also holds) so that any
concurrent delivery/TX is handled correctly.

Reported-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix AP powersave TX vs. wakeup race

There is a race between the TX path and the STA wakeup: while
a station is sleeping, mac80211 buffers frames until it wakes
up, then the frames are transmitted. However, the RX and TX
path are concurrent, so the packet indicating wakeup can be
processed while a packet is being transmitted.

This can lead to a situation where the buffered frames list
is emptied on the one side, while a frame is being added on
the other side, as the station is still seen as sleeping in
the TX path.

As a result, the newly added frame will not be send anytime
soon. It might be sent much later (and out of order) when the
station goes to sleep and wakes up the next time.

Additionally, it can lead to the crash below.

Fix all this by synchronising both paths with a new lock.
Both path are not fastpath since they handle PS situations.

In a later patch we'll remove the extra skb queue locks to
reduce locking overhead.

BUG: unable to handle kernel
NULL pointer dereference at 000000b0
IP: [<ff6f1791>] ieee80211_report_used_skb+0x11/0x3e0 [mac80211]
*pde = 00000000
Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
EIP: 0060:[<ff6f1791>] EFLAGS: 00210282 CPU: 1
EIP is at ieee80211_report_used_skb+0x11/0x3e0 [mac80211]
EAX: e5900da0 EBX: 00000000 ECX: 00000001 EDX: 00000000
ESI: e41d00c0 EDI: e5900da0 EBP: ebe458e4 ESP: ebe458b0
DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 8005003b CR2: 000000b0 CR3: 25a78000 CR4: 000407d0
DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
DR6: ffff0ff0 DR7: 00000400
Process iperf (pid: 3934, ti=ebe44000 task=e757c0b0 task.ti=ebe44000)
iwlwifi 0000:02:00.0: I iwl_pcie_enqueue_hcmd Sending command LQ_CMD (#4e), seq: 0x0903, 92 bytes at 3[3]:9
Stack:
e403b32c ebe458c4 00200002 00200286 e403b338 ebe458cc c10960bb e5900da0
ff76a6ec ebe458d8 00000000 e41d00c0 e5900da0 ebe458f0 ff6f1b75 e403b210
ebe4598c ff723dc1 00000000 ff76a6ec e597c978 e403b758 00000002 00000002
Call Trace:
[<ff6f1b75>] ieee80211_free_txskb+0x15/0x20 [mac80211]
[<ff723dc1>] invoke_tx_handlers+0x1661/0x1780 [mac80211]
[<ff7248a5>] ieee80211_tx+0x75/0x100 [mac80211]
[<ff7249bf>] ieee80211_xmit+0x8f/0xc0 [mac80211]
[<ff72550e>] ieee80211_subif_start_xmit+0x4fe/0xe20 [mac80211]
[<c149ef70>] dev_hard_start_xmit+0x450/0x950
[<c14b9aa9>] sch_direct_xmit+0xa9/0x250
[<c14b9c9b>] __qdisc_run+0x4b/0x150
[<c149f732>] dev_queue_xmit+0x2c2/0xca0

Cc: stable@vger.kernel.org
Reported-by: Yaara Rozenblum <yaara.rozenblum@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Reviewed-by: Stanislaw Gruszka <sgruszka@redhat.com>
[reword commit log, use a separate lock]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: move VHT related RX_FLAG to another variable

ieee80211_rx_status.flags is full. Define a new vht_flag
variable to be able to set more VHT related flags and make
room in flags.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Acked-by: Kalle Valo <kvalo@qca.qualcomm.com> [ath10k]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: optimise mixed AP/VLAN station removal

Teach sta_info_flush() to optionally also remove stations
from all VLANs associated with an AP interface to optimise
the station removal (in particular, synchronize_net().)

To not have to add the vlans argument throughout, do some
refactoring.

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

mac80211: optimise synchronize_net() for sta_info_flush

There's no reason to have one synchronize_net() for each
removed station, refactor the code slightly to have just
a single synchronize_net() for all stations.

Note that this is currently useless as hostapd removes
stations one by one and this coalescing never happens.

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

mac80211: don't delay station destruction

If we can assume that stations are never referenced by the
driver after sta_state returns (and this is true since the
previous iwlmvm patch and for all other drivers) then we
don't need to delay station destruction, and don't need to
play tricks with rcu_barrier() etc.

This should speed up some scenarios like hostapd shutdown.

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

mac80211: Tx frame latency statistics

Measure TX latency and jitter statistics per station per TID.
These Measurements are disabled by default and can be enabled
via debugfs.

Features included for each station's TID:

1. Keep count of the maximum and average latency of Tx frames.
2. Keep track of many frames arrived in a specific time range
(need to enable through debugfs and configure the bins ranges)

Signed-off-by: Matti Gottlieb <matti.gottlieb@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: use put_unaligned_le16 in mesh_plink_frame_tx

Use put_unaligned_le16 in mesh_plink_frame_tx.

Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add generic cipher scheme support

This adds generic cipher scheme support to mac80211, such schemes
are fully under control by the driver. On hw registration drivers
may specify additional HW ciphers with a scheme how these ciphers
have to be handled by mac80211 TX/RR. A cipher scheme specifies a
cipher suite value, a size of the security header to be added to
or stripped from frames and how the PN is to be verified on RX.

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

mac80211: implement SMPS for AP

When the driver requests to move to STATIC or DYNAMIC SMPS,
we send an action frame to each associated station and
reconfigure the channel context / driver.
Of course, non-MIMO stations are ignored.

The beacon isn't updated. The association response will
include the original capabilities. Stations that associate
while in non-OFF SMPS mode will get an action frame right
after association to inform them about our current state.
Note that we wait until the end of the EAPOL. Sending an
action frame before the EAPOL is finished can be an issue
for a few clients. Clients aren't likely to send EAPOL
frames in MIMO anyway.

When the SMPS configuration gets more permissive (e.g.
STATIC -> OFF), we don't wake up stations that are asleep
We remember that they don't know about the change and send
the action frame when they wake up.

When the SMPS configuration gets more restrictive (e.g.
OFF -> STATIC), we set the TIM bit for every sleeping STA.
uAPSD stations might send MIMO until they poll the action
frame, but this is for a short period of time.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
[fix vht streams loop, initialisation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Ensure tid_start_tx is protected by sta->lock

All accesses of the tid_start_tx lock should be protected
by sta->lock if there is any chance that another thread
could still be accessing the sta object.

Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

wireless: fix kernel-doc

Some kernel-doc fixes for forgotten fields and renamed things.

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

mac80211: add support for per-chain signal strength reporting

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[fix unit documentation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: provide race-free 64-bit traffic counters

Make the TX bytes/packets counters race-free by keeping
them per AC so concurrent TX on queues can't cause lost
or wrong updates. This works since each station belongs
to a single interface. While at it also make the bytes
counters 64-bit.

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

mac80211: cleanup suspend/resume on mesh mode

Remove not used any longer suspend/resume code.

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: clean up mesh HT operation

ieee80211_ht_cap_ie_to_sta_ht_cap() will clean up the
ht_supported flag and station bandwidth field for us
if the peer beacon doesn't have an HT capability element
(is operating as non-HT).

Also, we don't really need a special station ch_width
member to track the station operating mode any more so use
sta.bandwidth instead.

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: handle VHT operating mode notification

Handle the operating mode notification action frame.
When the supported streams or the bandwidth change
let the driver and rate control algorithm know.

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

mac80211: stop toggling IEEE80211_HT_CAP_SUP_WIDTH_20_40

For VHT, many more bandwidth changes are possible. As a first
step, stop toggling the IEEE80211_HT_CAP_SUP_WIDTH_20_40 flag
in the HT capabilities and instead introduce a bandwidth field
indicating the currently usable bandwidth to transmit to the
station. Of course, make all drivers use it.

To achieve this, make ieee80211_ht_cap_ie_to_sta_ht_cap() get
the station as an argument, rather than the new capabilities,
so it can set up the new bandwidth field.

If the station is a VHT station and VHT bandwidth is in use,
also set the bandwidth accordingly.

Doing this allows us to get rid of the supports_40mhz flag as
the HT capabilities now reflect the true capability instead of
the current setting.

While at it, also fix ieee80211_ht_cap_ie_to_sta_ht_cap() to not
ignore HT cap overrides when MCS TX isn't supported (not that it
really happens...)

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

wireless: fix kernel-doc

Fix most kernel-doc warnings, for some reason it
seems to have issues with __aligned, don't remove
the documentation entries it considers to be in
excess due to that.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: mesh power save basics

Add routines to
- maintain a PS mode for each peer and a non-peer PS mode
- indicate own PS mode in transmitted frames
- track neighbor STAs power modes
- buffer frames when neighbors are in PS mode
- add TIM and Awake Window IE to beacons
- release frames in Mesh Peer Service Periods

Add local_pm to sta_info to represent the link-specific power
mode at this station towards the remote station. When a peer
link is established, use the default power mode stored in mesh
config. Update the PS status if the peering status of a neighbor
changes.
Maintain a mesh power mode for non-peer mesh STAs. Set the
non-peer power mode to active mode during peering. Authenticated
mesh peering is currently not working when either node is
configured to be in power save mode.

Indicate the current power mode in transmitted frames. Use QoS
Nulls to indicate mesh power mode transitions.
For performance reasons, calls to the function setting the frame
flags are placed in HWMP routing routines, as there the STA
pointer is already available.

Add peer_pm to sta_info to represent the peer's link-specific
power mode towards the local station. Add nonpeer_pm to
represent the peer's power mode towards all non-peer stations.
Track power modes based on received frames.

Add the ps_data structure to ieee80211_if_mesh (for TIM map, PS
neighbor counter and group-addressed frame buffer).

Set WLAN_STA_PS flag for STA in PS mode to use the unicast frame
buffering routines in the tx path. Update num_sta_ps to buffer
and release group-addressed frames after DTIM beacons.

Announce the awake window duration in beacons if in light or
deep sleep mode towards any peer or non-peer. Create a TIM IE
similarly to AP mode and add it to mesh beacons. Parse received
Awake Window IEs and check TIM IEs for buffered frames.

Release frames towards peers in mesh Peer Service Periods. Use
the corresponding trigger frames and monitor the MPSP status.
Append a QoS Null as trigger frame if neccessary to properly end
the MPSP. Currently, in HT channels MPSPs behave imperfectly and
show large delay spikes and frame losses.

Signed-off-by: Marco Porsch <marco@cozybit.com>
Signed-off-by: Ivan Bezyazychnyy <ivan.bezyazychnyy@gmail.com>
Signed-off-by: Mike Krinkin <krinkin.m.u@gmail.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: split aggregation stop by reason

The initiator/tx doesn't really identify why an
aggregation session is stopped, give a reason
for stopping that more clearly identifies what's
going on. This will help tell the driver clearly
what is expected of it.

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

mac80211: optimise AP stop RCU handling

If there are VLANs, stopping an AP is inefficient as it
calls rcu_barrier() once for each interface (the VLANs
and the AP itself). Optimise this by moving rcu_barrier()
out of the station cleanups and calling it only once for
all interfaces combined.

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

mac80211: optimise roaming time again

The last fixes re-added the RCU synchronize penalty
on roaming to fix the races. Split up sta_info_flush()
now to get rid of that again, and let managed mode
(and only it) delay the actual destruction.

Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: remove final sta_info_flush()

When all interfaces have been removed, there can't
be any stations left over, so there's no need to
flush again. Remove this, and all code associated
with it, which also simplifies the function.

Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: fix station destruction in AP/mesh modes

Unfortunately, commit b22cfcfcae5b, intended to speed up roaming
by avoiding the synchronize_rcu() broke AP/mesh modes as it moved
some code into that work item that will still call into the driver
at a time where it's no longer expected to handle this: after the
AP or mesh has been stopped.

To fix this problem remove the per-station work struct, maintain a
station cleanup list instead and flush this list when stations are
flushed. To keep this patch smaller for stable, do this when the
stations are flushed (sta_info_flush()). This unfortunately brings
back the original roaming delay; I'll fix that again in a separate
patch.

Also, Ben reported that the original commit could sometimes (with
many interfaces) cause long delays when an interface is set down,
due to blocking on flush_workqueue(). Since we now maintain the
cleanup list, this particular change of the original patch can be
reverted.

Cc: stable@vger.kernel.org [3.7]
Reported-by: Ben Greear <greearb@candelatech.com>
Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: re-organize the rx rate calculation logic

Currently the logic to fill a struct rate_info with
a STA's last RX rate is accessible only in the cfg.c.
As the RX rate calculation might be needed elsewhere,
split this out into a separate function.

Signed-off-by: Saravana <saravanad@posedge.com>
[fix various whitespace issues, reword commit log]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add debugfs file for last ack signal

Add a debugfs file showing the signal strength
of the ack frame that is received for the
currently sent tx packet

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

mac80211: support drivers reporting VHT RX

Add support to mac80211 for having drivers report
received VHT MCS information.

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

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>

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>

mac80211: use call_rcu() on sta deletion

mac80211 calls synchronize_rcu() on sta deletion,
which increase the roaming time significantly.

Convert it into a call_rcu() mechanism, in order
to avoid blocking. Since some of the cleanup
functions might sleep, schedule from the call_rcu
callback a new work that will do the actual cleanup.

In order to make sure the cleanup occurs before
the interface went down, flush local->workqueue
on ieee80211_do_stop().

Signed-off-by: Yoni Divinsky <yoni.divinsky@ti.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add missing kernel-doc

Add a few kernel-doc descriptions that were missed
during mesh development.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Ashok Nagarajan <ashok@cozybit.com>
Acked-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: add some missing kernel-doc

Add a few kernel-doc descriptions that were missed
during development.

Reported-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211: Convert compare_ether_addr to ether_addr_equal by hand

spatch/coccinelle isn't perfect. It doesn't understand
__aligned(x) and doesn't convert functions it can't parse.

Convert the remaining compare_ether_addr uses.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

mac80211: Implement HT mixed protection mode

Section 9.23.3.5 of IEEE 80211s standard describes the protection rules for
HT mesh STA in a MBSS. Three HT protection modes are supported for now:

non-HT mixed mode - is selected if any non-HT peers are present in our MBSS.
20MHz-protection mode - is selected if all peers in our 20/40MHz MBSS support
HT and atleast one HT20 peer is present.
no-protection mode - is selected otherwise.

This is a limited implementation of 9.23.3.5, which only considers mesh peers
when determining the HT protection mode. Station's channel_type needs to be
maintained.

Signed-off-by: Ashok Nagarajan <ashok@cozybit.com>
Reviewed-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: Implement mesh synchronization framework

This patch adds MBSS extensible synchronization framework (Sec.
13.13.2 of IEEE Std. 802.11-2012).

The framework is implemented via an ops table which defines the
following functions:

rx_bcn_presp() - this is called every time a mesh beacon is
received.
adjust_tbtt() - this is called immediately before a beacon is about
to be transmitted.

The default neighbor offset synchronization defined in the standard is
implemented. We also provide template functions for vendor specific
methods.

When neighbor offset synchronization is active (which is the default)
mesh neighbors in the same MBSS will track timing offsets to each other
and compensate clock drift.

In our tests we observed that this mesh synchronization implementation
successfully corrected drifts between stations of ~2PPM while
introducing a jitter of ~20us.

It is also possible to test this framework on mac80211_hwsim simulated
phys to see how it behaves under different topologies, over poor links,
etc.

Signed-off-by: Marco Porsch <marco.porsch@s2005.tu-chemnitz.de>
Signed-off-by: Pavel Zubarev <pavel.zubarev@gmail.com>
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: remove channel type argument from rate_update

The channel type argument to the rate_update()
callback isn't really the correct way to give
the rate control algorithm about the desired
RX bandwidth of the peer.

Remove this argument, and instead update the
STA capabilities with 20/40 appropriately. The
SMPS update done by this callback works in the
same way, so this makes the callback cleaner.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

mac80211: fix mesh airtime link metric estimating

Airtime link metric estimation was broken in HT mesh, use
cfg80211_calculate_bitrate to get the right rate value.

Also factor out tx rate copying from sta_set_sinfo().

Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: use compare_ether_addr on MAC addresses instead of memcmp

Because of the constant size and guaranteed 16 bit alignment, the inline
compare_ether_addr function is much cheaper than calling memcmp.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

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>

mac80211: remove dummy STA support

The dummy STA support was added because I didn't
want to change the driver API at the time. Now
that we have state transitions triggering station
add/remove in the driver, we only call add once a
station reaches ASSOCIATED, so we can remove the
dummy station stuff again.

While at it, tighten the RX check and accept only
port control (EAP) frames from the AP station if
it's not associated yet -- in other cases there's
no race.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: add sta_state callback

(based on Eliad's patch)

Add a callback to notify the low-level driver whenever
the state of a station changes. The driver is only
notified when the station is actually in the mac80211
hash table, not for pre-insert state transitions.

To allow the driver to replace sta_add/remove calls
with this, call extra transitions with the NOTEXIST
state.

This callback can fail, so we need to be careful in
handling it when a station is inserted, particularly
in the IBSS case where we still keep the station entry
around for mac80211 purposes.

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: add NOTEXIST station state

This will be used by drivers later if they
need to have stations inserted all the time,
in mac80211 has no purpose, is never used
and sta_state starts out in NONE.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: station state transition error handling

In the future, when we start notifying drivers,
state transitions could potentially fail. To make
it easier to distinguish between programming bugs
and driver failures:
* rename sta_info_move_state() to
sta_info_pre_move_state() which can only be
called before the station is inserted (and
check this with a new station flag).
* rename sta_info_move_state_checked() to just
plain sta_info_move_state(), as it will be
the regular function that can fail for more
than just one reason (bad transition or an
error from the driver)

This makes the programming model easier -- one of
the functions can only be called before insertion
and can't fail, the other can fail.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

cfg80211: Return beacon loss count in station

If station info contains a beacon loss count, return
it to userspace.

Signed-off-by: Paul Stewart <pstew@chromium.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

mac80211: make address arguments to sta_info_alloc const

No real changes, just note that they are const.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: refactor station state transitions

Station entries can have various states, the most
important ones being auth, assoc and authorized.
This patch prepares us for telling the driver about
these states, we don't want to confuse drivers with
strange transitions, so with this we enforce that
they move in the right order between them (back and
forth); some transitions might happen before the
driver even knows about the station, but at least
runtime transitions will be ordered correctly.

As a consequence, IBSS and MESH stations will now
have the ASSOC flag set (so they can transition to
AUTHORIZED), and we can get rid of a special case
in TX processing.

When freeing a station, unwind the state so that
other parts of the code (or drivers later) can rely
on the transitions.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: remove unused function declaration

Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

mac80211: remove unused ASSOC_AP flag

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>

mac80211: send unexpected 4addr event

Implement the cfg80211 notification but only send
one event per associated station to avoid having
tons of events if the station thinks it should be
allowed to use 4addr frames but it isn't.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

mac80211: reply only once to each PS-poll

If a PS-poll frame is retried (but was received)
there is no way to detect that since it has no
sequence number. As a consequence, the standard
asks us to not react to PS-poll frames until the
response to one made it out (was ACKed or lost).

Implement this by using the WLAN_STA_SP flags to
also indicate a PS-Poll "service period" and the
IEEE80211_TX_STATUS_EOSP flag for the response
packet to indicate the end of the "SP" as usual.

We could use separate flags, but that will most
likely completely confuse drivers, and while the
standard doesn't exclude simultaneously polling
using uAPSD and PS-Poll, doing that seems quite
problematic.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: implement uAPSD

Add uAPSD support to mac80211. This is probably not
possible with all devices, so advertising it with
the cfg80211 flag will be left up to drivers that
want it.

Due to my previous patches it is now a fairly
straight-forward extension. Drivers need to have
accurate TX status reporting for the EOSP frame.
For drivers that buffer themselves, the provided
APIs allow releasing the right number of frames,
but then drivers need to set EOSP and more-data
themselves. This is documented in more detail in
the new code itself.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: split PS buffers into ACs

For uAPSD support we'll need to have per-AC PS
buffers. As this is a major undertaking, split
the buffers before really adding support for
uAPSD. This already makes some reference to the
uapsd_queues variable, but for now that will
never be non-zero.

Since book-keeping is complicated, also change
the logic for keeping a maximum of frames only
and allow 64 frames per AC (up from 128 for a
station).

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: unify TIM bit handling

Currently, the TIM bit for a given station is set
and cleared all over the place. Since the logic to
set/clear it will become much more complex when we
add uAPSD support, as a first step let's collect
the entire logic in one place. This requires a few
small adjustments to other places.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: data path modification for TDLS peers

Mark the STA entries of enabled TDLS peers with a new "peer authorized"
flag.

During link setup, allow special TDLS setup frames through the AP, but
otherwise drop all packets destined to the peer. This is required by the
TDLS (802.11z) specification in order to prevent reordering of MSDUs
between the AP and direct paths.

When setup completes and the peer is authorized, send data directly,
bypassing the AP.

In the Rx path, allow data to be received directly from TDLS peers.

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Cc: Kalyan C Gaddam <chakkal@iit.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

nl80211/mac80211: allow adding TDLS peers as stations

When adding a TDLS peer STA, mark it with a new flag in both nl80211 and
mac80211. Before adding a peer, make sure the wiphy supports TDLS and
our operating mode is appropriate (managed).

In addition, make sure all peers are removed on disassociation.

A TDLS peer is first added just before link setup is initiated. In later
setup stages we have more info about peer supported rates, capabilities,
etc. This info is reported via nl80211_set_station().

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Cc: Kalyan C Gaddam <chakkal@iit.edu>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: retry sending failed BAR frames later instead of tearing down aggr

Unfortunately failed BAR tx attempts happen more frequently than I
expected, and the resulting aggregation teardowns cause performance
issues, as the aggregation session does not always get re-established
properly.
Instead of tearing down the entire aggr session, we can simply store the
SSN of the last failed BAR tx attempt, wait for the first successful
tx status event, and then send another BAR with the same SSN.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix race condition between assoc_done and first EAP packet

When associating to an AP, the station might miss the first EAP
packet that the AP sends due to a race condition between the association
success procedure and the rx flow in mac80211.
In such cases, the packet might fall in ieee80211_rx_h_check due to
the fact that the relevant rx->sta wasn't allocated yet.
Allocation of the relevant station info struct before actually
sending the association request and setting it with a new
dummy_sta flag solve this problem.
The station will accept only EAP packets from the AP while it
is in the pre-association/dummy state.
This dummy station entry is not seen by normal sta_info_get()
calls, only by sta_info_get_bss_rx().
The driver is not notified for the first insertion of the
dummy station. The driver is notified only after the association
is complete and the dummy flag is removed from the station entry.
That way, all the rest of the code flow should be untouched by
this change.

Signed-off-by: Guy Eilam <guy@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: simplify RX PN/IV handling

The current rx->queue value is slightly confusing.
It is set to 16 on non-QoS frames, including data,
and then used for sequence number and PN/IV checks.
Until recently, we had a TKIP IV checking bug that
had been introduced in 2008 to fix a seqno issue.
Before that, we always used TID 0 for checking the
PN or IV on non-QoS packets.

Go back to the old status for PN/IV checks using
the TID 0 counter for non-QoS by splitting up the
rx->queue value into "seqno_idx" and "security_idx"
in order to avoid confusion in the future. They
each have special rules on the value used for non-
QoS data frames.

Since the handling is now unified, also revert the
special TKIP handling from my patch
"mac80211: fix TKIP replay vulnerability".

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: Stop BA session event from device

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: Shahar Levi <shahar_levi@ti.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

nl80211: Move peer link state definition to nl80211

These definitions need to be exposed now that we can set the peer link
states via NL80211_ATTR_STA_PLINK_STATE. They were already being
(opaquely) reported by NL80211_STA_INFO_PLINK_STATE.

Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

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>

nl80211: Let userspace drive the peer link management states.

Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: add a function for setting the TIM bit for a specific station

This allows a driver to buffer frames for a PS station and tell mac80211
to wake it up even though mac80211 does not have any buffered frames for
it.
This is necessary for properly handling aggregation related buffering,
in ath9k, because the driver needs to keep its frames in order to keep
track of the Block-ACK window.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

{mac|nl}80211: Add station connected time

Add station connected time in debugfs. This will be helpful to get a
measure of stability of the connection and for debugging stress issues

Cc: Senthilkumar Balasubramanian <Senthilkumar.Balasubramanian@Atheros.com>
Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: clean up station cleanup timer

We currently run this timer exactly once when
a new mac80211 device is registered, but that
is completely pointless since it will have no
work to do at all. Therefore, remove that and
also simplify some code using the timer.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Fix common misspellings

Fixes generated by 'codespell' and manually reviewed.

Signed-off-by: Lucas De Marchi <lucas.demarchi@profusion.mobi>

mac80211: add support for showing the last rx bitrate

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

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>

nl80211/mac80211: Report signal average

Extend nl80211 to report an exponential weighted moving average (EWMA) of the
signal value. Since the signal value usually fluctuates between different
packets, an average can be more useful than the value of the last packet.

This uses the recently added generic EWMA library function.

--
v2: fix ABI breakage and change factor to be a power of 2.

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix RX aggregation locking

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: Johannes Berg <johannes.berg@intel.com>
Acked-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: implement packet loss notification

For drivers that have accurate TX status reporting
we can report the number of consecutive lost packets
to userspace using the new cfg80211 CQM event. The
threshold is fixed right now, this may need to be
improved in the future.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

Revert "nl80211/mac80211: Report signal average"

This reverts commit 86107fd170bc379869250eb7e1bd393a3a70e8ae.

This patch inadvertantly changed the userland ABI.

Signed-off-by: John W. Linville <linville@tuxdriver.com>

nl80211/mac80211: Report signal average

Extend nl80211 to report an exponential weighted moving average (EWMA) of the
signal value. Since the signal value usually fluctuates between different
packets, an average can be more useful than the value of the last packet.

This uses the recently added generic EWMA library function.

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

cfg80211/mac80211: allow per-station GTKs

This adds API to allow adding per-station GTKs,
updates mac80211 to support it, and also allows
drivers to remove a key from hwaccel again when
this may be necessary due to multiple GTKs.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

mac80211: AMPDU rx reorder timeout timer

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: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix the for_each_sta_info macro

Because of an ambiguity in the for_each_sta_info macro, it can
currently only be used if the third parameter is set to 'sta'.
Fix this by renaming the parameter to '_sta'.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: change RX aggregation locking

To prepare for allowing drivers to sleep in
ampdu_action, change the locking in the RX
aggregation code to use a mutex, so that it
would already allow drivers to sleep. But
explicitly disable BHs around the callback
for now since the TX part cannot yet sleep,
and drivers' locking might require it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: defer RX 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 prepare, move it out
into the aggregation work.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

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>

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>

mac80211: use RCU for RX aggregation

Currently we allocate some memory for each RX
aggregation session and additionally keep a
flag indicating whether or not it is valid.
By using RCU to protect the pointer and making
sure that the memory is fully set up before it
becomes visible to the RX path, we can remove
the need for the bool that indicates validity,
as well as for locking on the RX path since it
is always synchronised against itself, and we
can guarantee that all other modifications are
done when the structure is not visible to the
RX path.

The net result is that since we remove locking
requirements from the RX path, we can in the
future use any kind of lock for the setup and
teardown code paths.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: simplify station/aggregation code

A number of places use RCU locking for accessing
the station list, even though they do not need
to. Use mutex locking instead to prepare for the
locking changes I want to make. The mlme code is
also using a WLAN_STA_DISASSOC flag that has the
same meaning as WLAN_STA_BLOCK_BA, so use that.

While doing so, combine places where we loop
over stations twice, and optimise away some of
the loops by checking if the hardware supports
aggregation at all first.

Also fix a more theoretical race condition: right
now we could resume, set up an aggregation session,
and right after tear it down again due to the code
that is needed for hardware reconfiguration here.
Also mark add a comment to that code marking it as
a workaround.

Finally, remove a pointless aggregation disabling
loop when an interface is stopped, directly after
that we remove all stations from it which will also
disable all aggregation sessions that may still be
active, and does so in a race-free way unlike the
current loop that doesn't block new sessions.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: move plink state

For some odd reason, the plink_state enum is
declared in the middle between aggregation
related structures. Move it down to make the
file easier to read.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

wireless: fix sta_info.h kernel-doc warnings

Fix sta_info.h kernel-doc warnings:

Warning(net/mac80211/sta_info.h:164): No description found for parameter 'tid_active_rx[STA_TID_NUM]'
Warning(net/mac80211/sta_info.h:164): Excess struct/union/enum/typedef member 'tid_state_rx' description in 'sta_ampdu_mlme'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: clean up/fix aggregation code

The aggregation code has a number of quirks, like
inventing an unneeded WLAN_BACK_TIMER value and
leaking memory under certain circumstances during
station destruction. Fix these issues by using
the regular aggregation session teardown code and
blocking new aggregation sessions, all before the
station is really destructed.

As a side effect, this gets rid of the long code
block to destroy aggregation safely.

Additionally, rename tid_state_rx which can only
have the values IDLE and OPERATIONAL to
tid_active_rx to make it easier to understand
that there is no bitwise stuff going on on the
RX side -- the TX side remains because it needs
to keep track of the driver and peer states.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: rename WLAN_STA_SUSPEND to WLAN_STA_BLOCK_BA

I want to use it during station destruction as well
so rename it to WLAN_STA_BLOCK_BA which is also the
only use of it now.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: deprecate RX status noise

The noise value as is won't be used, isn't
filled by most drivers and doesn't really
make a whole lot of sense on a per packet
basis -- proper cfg80211 survey support in
mac80211 will need to be different.

Mark the struct member as deprecated so it
will be removed from drivers.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: Deny TX BA session requests during disassociation

In associated state, when bringing an interface down, existing
BA sessions are torn down. When this is in progress, nothing
prevents mac80211 from accepting another BA session start request.

Use a new station flag to fix this.

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: allow station add/remove to sleep

Many drivers would like to sleep during station
addition and removal, and currently have a high
complexity there from not being able to.

This introduces two new callbacks sta_add() and
sta_remove() that drivers can implement instead
of using sta_notify() and that can sleep, and
the new sta_add() callback is also allowed to
fail.

The reason we didn't do this previously is that
the IBSS code wants to insert stations from the
RX path, which is a tasklet, so cannot sleep.
This patch will keep the station allocation in
that path, but moves adding the station to the
driver out of line. Since the addition can now
fail, we can have IBSS peer structs the driver
rejected -- in that case we still talk to the
station but never tell the driver about it in
the control.sta pointer. If there will ever be
a driver that has a low limit on the number of
stations and that cannot talk to any stations
that are not known to it, we need to do come up
with a new strategy of handling larger IBSSs,
maybe quicker expiry or rejecting peers.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: allow station updates on ap interfaces for vlan stations

Since the per-vif station changes, sta_info_get on the ap sdata no
longer returns entries for stations on ap vlans. This causes issues
with hostapd, which currently always passes the ap interface name to
nl80211 calls. This patch provides bug compatibility with the earlier
versions until hostapd is fixed.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: make station management completely depend on vif

The station management currently uses the virtual
interface, but you cannot add the same station to
multiple virtual interfaces if you're communicating
with it in multiple ways.

This restriction should be lifted so that in the
future we can, for instance, support bluetooth 3
with an access point that mac80211 is already
associated to.

We can do that by requiring all sta_info_get users
to provide the virtual interface and making the RX
code aware that an address may match more than one
station struct. Thanks to the previous patches this
one isn't all that large and except for the RX and
TX status paths changes has low complexity.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: Fix missing kernel-doc notation

Fix the following htmldocs warnings:

Warning(net/mac80211/sta_info.h:322): No description found for parameter 'drv_unblock_wk'
Warning(net/mac80211/sta_info.h:322): No description found for parameter 'drv_unblock_wk'

Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: let sta_info_get_by_idx get sta by sdata

Instead of filtering by device, directly look up by sdata.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: async station powersave handling

Some devices require that all frames to a station
are flushed when that station goes into powersave
mode before being able to send frames to that
station again when it wakes up or polls -- all in
order to avoid reordering and too many or too few
frames being sent to the station when it polls.

Normally, this is the case unless the station
goes to sleep and wakes up very quickly again.
But in that case, frames for it may be pending
on the hardware queues, and thus races could
happen in the case of multiple hardware queues
used for QoS/WMM. Normally this isn't a problem,
but with the iwlwifi mechanism we need to make
sure the race doesn't happen.

This makes mac80211 able to cope with the race
with driver help by a new WLAN_STA_PS_DRIVER
per-station flag that can be controlled by the
driver and tells mac80211 whether it can transmit
frames or not. This flag must be set according to
very specific rules outlined in the documentation
for the function that controls it.

When we buffer new frames for the station, we
normally set the TIM bit right away, but while
the driver has blocked transmission to that sta
we need to avoid that as well since we cannot
respond to the station if it wakes up due to the
TIM bit. Once the driver unblocks, we can set
the TIM bit.

Similarly, when the station just wakes up, we
need to wait until all other frames are flushed
before we can transmit frames to that station,
so the same applies here, we need to wait for
the driver to give the OK.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: deprecate qual value

This value is unused by mac80211, because it was only
be used by wireless extensions, and turned out to not
be useful there because the quality value needs to be
comparable between scan results and the current value
which is impossible when the qual value is calculated
taking into account noise, for example.

Since it is unused anyway, this patch deprecates it
in the hope that drivers will remove their sometimes
quite expensive calculations of the value.

I'm open to actual uses of the value, but the best
way of using it seems to be what the Intel drivers do
which should probably be generalised if we have noise
values from the hardware.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

cfg80211/mac80211: use debugfs_remove_recursive

We can save a lot of code and pointers in the structs
by using debugfs_remove_recursive().

First, change cfg80211 to use debugfs_remove_recursive()
so that drivers do not need to clean up any files they
added to the per-wiphy debugfs (if and only if they are
ok to be accessed until after wiphy_unregister!).

Then also make mac80211 use debugfs_remove_recursive()
where necessary -- it need not remove per-wiphy files
as cfg80211 now removes those, but netdev etc. files
still need to be handled but can now be removed without
needing struct dentry pointers to all of them.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix PS-poll response, race

When a station queries us for a PS-poll response, we wrongly
queue the frame on the virtual interface's queue rather than
the pending queue.

Additionally, fix a race condition where we could potentially
send multiple frames to the sleeping station due to using a
station flag rather than a packet flag. When converting to a
packet flag, we can also convert p54 and remove the filter
clearing we added for it.

(Also remove a now dead function)

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Reported-by: Bob Copeland <me@bobcopeland.com>
Tested-by: Bob Copeland <me@bobcopeland.com>
Cc: Christian Lamparter <chunkeey@web.de>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: improve per-sta debugfs

We had code for a number of files, that we didn't publish
in debugfs, fix that. Also make the agg_status file layout
more readable and add more information to it.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix kernel-doc

Moving information from config_interface to bss_info_changed
removed struct ieee80211_if_conf which the documentation still
refers to, additionally there's one kernel-doc description too
much and one other missing, fix all this.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: cancel/restart all timers across suspend/resume

We forgot to cancel all timers in mac80211 when suspending.
In particular we forgot to deal with some things that can
cause hardware reconfiguration -- while it is down.

While at it we go ahead and add a warning in ieee80211_sta_work()
if its run while the suspend->resume cycle is in effect. This
should not happen and if it does it would indicate there is
a bug lurking in either mac80211 or mac80211 drivers.

With this now wpa_supplicant doesn't blink when I go to suspend
and resume where as before there where issues with some timers
running during the suspend->resume cycle. This caused a lot of
incorrect assumptions and would at times bring back the device
in an incoherent, but mostly recoverable, state.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: Add a timeout for frames in the RX reorder buffer

This patch allows skbs to be released from the RX reorder buffer in
case they have been there for an unexpectedly long time without us
having received the missing frames before them. Previously, these
frames were only released when the reorder window moved and that could
take very long time unless new frames were received constantly (e.g.,
TCP connections could be killed more or less indefinitely).

This situation should not happen very frequently, but it looks like
there are some scenarious that trigger it for some reason. As such,
this should be considered mostly a workaround to speed up recovery
from unexpected siutation that could result in connections hanging for
long periods of time.

The changes here will only check for timeout situation when adding new
RX frames to the reorder buffer. It does not handle all possible
cases, but seems to help for most cases that could result from common
network usage (e.g., TCP retrying at least couple of times). For more
completely coverage, a timer could be used to periodically check
whether there are any frames remaining in the reorder buffer if no new
frames are received.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: convert to cfg80211 IBSS API

This converts mac80211 to the new cfg80211 IBSS API, the
wext handling functions are called where appropriate.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211/iwlwifi: move virtual A-MDPU queue bookkeeping to iwlwifi

This patch removes all the virtual A-MPDU-queue bookkeeping from
mac80211. Curiously, iwlwifi already does its own bookkeeping, so
it doesn't require much changes except where it needs to handle
starting and stopping the queues in mac80211.

To handle the queue stop/wake properly, we rewrite the software
queue number for aggregation frames and internally to iwlwifi keep
track of the queues that map into the same AC queue, and only talk
to mac80211 about the AC queue. The implementation requires calling
two new functions, iwl_stop_queue and iwl_wake_queue instead of the
mac80211 counterparts.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Reinette Chattre <reinette.chatre@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix aggregation to not require queue stop

Instead of stopping the entire AC queue when enabling aggregation
(which was only done for hardware with aggregation queues) buffer
the packets for each station, and release them to the pending skb
queue once aggregation is turned on successfully.

We get a little more code, but it becomes conceptually simpler and
we can remove the entire virtual queue mechanism from mac80211 in
a follow-up patch.

This changes how mac80211 behaves towards drivers that support
aggregation but have no hardware queues -- those drivers will now
not be handed packets while the aggregation session is being
established, but only after it has been fully established.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: Tear down aggregation sessions for suspend/resume

When the driver has been notified with a STA_REMOVE, it tears down
the internal ADDBA state. On resume, trying to initiate aggregation would
fail because mac80211 has not cleared the operational state for that <TID,STA>.
This can be fixed by tearing down the existing sessions on a suspend.

Also, the driver can initiate a new BA session when suspend is in progress.
This is fixed by marking the station as being in suspend state and
denying ADDBA requests for such STAs.

Signed-off-by: Sujith <Sujith.Manoharan@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: add missing kernel-doc

Document the new shutdown member.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix aggregation for hardware with ampdu queues

Hardware with AMPDU queues currently has broken aggregation.

This patch fixes it by making all A-MPDUs go over the regular AC queues,
but keeping track of the hardware queues in mac80211. As a first rough
version, it actually stops the AC queue for extended periods of time,
which can be removed by adding buffering internal to mac80211, but is
currently not a huge problem because people rarely use multiple TIDs
that are in the same AC (and iwlwifi currently doesn't operate as AP).

This is a short-term fix, my current medium-term plan, which I hope to
execute soon as well, but am not sure can finish before .30, looks like
this:
1) rework the internal queuing layer in mac80211 that we use for
fragments if the driver stopped queue in the middle of a fragmented
frame to be able to queue more frames at once (rather than just a
single frame with its fragments)
2) instead of stopping the entire AC queue, queue up the frames in a
per-station/per-TID queue during aggregation session initiation,
when the session has come up take all those frames and put them
onto the queue from 1)
3) push the ampdu queue layer abstraction this patch introduces in
mac80211 into the driver, and remove the virtual queue stuff from
mac80211 again

This plan will probably also affect ath9k in that mac80211 queues the
frames instead of passing them down, even when there are no ampdu queues.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix aggregation timer lockups

As far as I can tell, there are possible lockups because both the RX
session_timer and TX addba_resp_timer are del_timer_sync'ed under
the sta spinlock which both timer functions take. Additionally, the
TX agg code seems to leak memory when TX aggregation is not disabled
before the sta_info is freed.

Fix this by making the free code a little smarter in the RX agg case,
and actually make the sta_info_destroy code free the TX agg info in
the TX agg case. We won't notify the peer, but it'll notice something
is wrong anyway, and normally this only happens after we've told it
in some other way we will no longer talk to it.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix RX aggregation timeouts

The values are in TUs (1.024ms), not ms.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: remove stray aggregation debugfs definition

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: 802.11w - STA flag for MFP

Add flags for setting STA entries and struct ieee80211_if_sta to
indicate whether management frame protection (MFP) is used.

Signed-off-by: Jouni Malinen <j@w1.fi>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: remove an unused definition (MAX_STA_COUNT) in sta_info.h.

This patch removes an unused definition of MAX_STA_COUNT in sta_info.h.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: more kernel-doc fixes

Fix (delete) more mac80211 kernel-doc:

Warning(linux-2.6.28-git13//include/net/mac80211.h:375): Excess struct/union/enum/typedef member 'retry_count' description in 'ieee80211_tx_info'
Warning(linux-2.6.28-git13//net/mac80211/sta_info.h:308): Excess struct/union/enum/typedef member 'last_txrate' description in 'sta_info'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: remove more excess kernel-doc

Delete kernel-doc struct descriptions for fields that don't exist:

Warning(include/net/mac80211.h:1263): Excess struct/union/enum/typedef member 'conf_ht' description in 'ieee80211_ops'
Warning(net/mac80211/sta_info.h:309): Excess struct/union/enum/typedef member 'addr' description in 'sta_info'
Warning(net/mac80211/sta_info.h:309): Excess struct/union/enum/typedef member 'aid' description in 'sta_info'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
cc: Johannes Berg <johannes@sipsolutions.net>
cc: John W. Linville <linville@tuxdriver.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix two kernel-doc warnings

One parameter wasn't described and one I forgot to update when
renaming it; also update TBDs in sta_info.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211/drivers: rewrite the rate control API

So after the previous changes we were still unhappy with how
convoluted the API is and decided to make things simpler for
everybody. This completely changes the rate control API, now
taking into account 802.11n with MCS rates and more control,
most drivers don't support that though.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix debugfs lockup

When debugfs_create_dir fails, sta_info_debugfs_add_work will not
terminate because it will find the same station again and again.
This is possible whenever debugfs fails for whatever reason; one
reason is a race condition in mac80211, unfortunately we cannot
do much about it, so just document it, it just means some station
may be missing from debugfs.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: remove wme_tx_queue and wme_rx_queue from net/mac80211/sta_info.h

This patch removes wme_tx_queue and wme_rx_queue from struct sta_info
and from the debugfs sub-structure of struct sta_info
in net/mac80211/sta_info.h, as they are useless and not used.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: clean up rate control API

Long awaited, hard work. This patch totally cleans up the rate control
API to remove the requirement to include internal headers outside of
net/mac80211/.

There's one internal use in the PID algorithm left for mesh networking,
we'll have to figure out a way to clean that one up and decide how to
do the peer link evaluation, possibly independent of the rate control
algorithm or via new API.

Additionally, ath9k is left using the cross-inclusion hack for now, we
will add new API where necessary to make this work properly, but right
now I'm not expert enough to do it. It's still off better than before.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix sta_info kernel-doc warning

Sorry, forgot to run kernel-doc and just got the output from the nightly
run by email, this fixes a warning which I introduced when doing the
first RC API cleanups.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: share sta_info->ht_info

Rate control algorithms may need access to a station's
HT capabilities, so share the ht_info struct in the
public station API.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: move txrate_idx into RC algorithms

The sta_info->txrate_idx member isn't used by all RC algorithms
in the way it was intended to be used, move it into those that
require it (only PID) and keep track in the core code of which
rate was last used for reporting to userspace and the mesh MLME.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: share sta->supp_rates

As more preparation for a saner rate control algorithm API,
share the supported rates bitmap in the public API.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: move last_txrate_idx into RC algorithms

This variable in sta_info is only used in a meaningful way
by the Intel RC algorithms, so move it into those.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: small rate control changes

This patch fixes mac80211 to not rely on the rate control
algorithm to update sta->tx_retry_failed and sta->tx_retry_count
(even if we don't currently use them), removes a number of
completely unused values we don't even show in debugfs and
changes the code in ieee80211_tx_status() to not look up the
sta_info repeatedly.

The only behaviour change here would be not calling the rate
control function rate_control_tx_status() when no sta_info is
found, but all rate control algorithms ignore such calls anyway.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: share STA information with driver

This patch changes mac80211 to share some more data about
stations with drivers. Should help iwlwifi and ath9k when
they get around to updating, and might also help with
implementing rate control algorithms without internals.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: move ieee80211_sta_expire

ieee80211_sta_expire uses the internal __sta_info_unlink
function which can become static if this function is moved
to sta_info.c.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: add missing kernel-doc

Fix mac80211 kernel-doc missing struct field:

Warning(linux-2.6.27-rc1-git2//net/mac80211/sta_info.h:329): No description found for parameter 'tid_seq[IEEE80211_QOS_CTL_TID_MASK + 1]'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix TX sequence numbers

This patch makes mac80211 assign proper sequence numbers to
QoS-data frames. It also removes the old sequence number code
because we noticed that only the driver or hardware can assign
sequence numbers to non-QoS-data and especially management
frames in a race-free manner because beacons aren't passed
through mac80211's TX path.

This patch also adds temporary code to the rt2x00 drivers to
not break them completely, that code will have to be reworked
for proper sequence numbers on beacons.

It also moves sequence number assignment down in the TX path
so no sequence numbers are assigned to frames that are dropped.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: fix lots of kernel-doc

Fix more than 50 kernel-doc warnings in ieee80211/mac80211 kernel-doc notation.
Fix a few typos also.

Note: Some fields are marked as TBD and need to have their description
corrected.

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: use separate spinlock for sta flags

David Ellingsworth posted a bug that was only noticable on UP/NO-PREEMPT
and Michael correctly analysed it to be a spin_lock_bh() section within
a spin_lock_irqsave() section. This adds a separate spinlock for the
sta_info flags to fix that issue and avoid having to take much care
about where the sta flag manipulation functions are called.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Reported-By: David Ellingsworth <david@identd.dyndns.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: remove channel use statistics

The useless channel use statistics are quite a lot of code, currently
use integer divisions in the packet fast path, are rather inaccurate
since they do not account for retries and finally nobody even cares.
Hence, remove them completely.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

mac80211: move TX info into skb->cb

This patch converts mac80211 and all drivers to have transmit
information and status in skb->cb rather than allocating extra
memory for it and copying all the data around. To make it fit,
a union is used where only data that is necessary for all steps
is kept outside of the union.

A number of fixes were done by Ivo, as well as the rt2x00 part
of this patch.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>