When MCS rates start to get bad in 2.4 GHz because of long range or
strong interference, CCK rates can be a lot more robust.

This patch adds a pseudo MCS group containing CCK rates (long preamble
in the lower 4 slots, short preamble in the upper slots).
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
[make minstrel_ht_get_stats static]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Bail out if no update is made to the SMPS state. This
allows the driver to avoid duplicating the state.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

We've got a couple of races when enabling powersave with an AP for
off-channel operation. The first is fairly simple. If we go off-channel
before the nullfunc frame to enable PS is transmitted then it may not be
received by the AP. Add a flush after enabling off-channel PS to prevent
this from happening.

The second race is a bit more subtle. If the driver supports QoS and has
frames queued when the nullfunc frame is queued, those frames may get
transmitted after the nullfunc frame. If PM is not set then the AP is
being told that we've exited PS before we go off-channel and may try to
deliver frames. To prevent this, add a flush after stopping the queues
but before passing the nullfunc frame to the driver.
Signed-off-by: NSeth Forshee <seth.forshee@canonical.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Scans currently work by stopping the netdev tx queues but leaving the
mac80211 queues active. This stops the flow of incoming packets while
still allowing mac80211 to transmit nullfunc and probe request frames to
facilitate scanning. However, the driver may try to wake the mac80211
queues while in this state, which will also wake the netdev queues.

To prevent this, add a new queue stop reason,
IEEE80211_QUEUE_STOP_REASON_OFFCHANNEL, to be used when stopping the tx
queues for off-channel operation. This prevents the netdev queues from
waking when a driver wakes the mac80211 queues.

This also stops all frames from being transmitted, even those meant to
be sent off-channel. Add a new tx control flag,
IEEE80211_TX_CTL_OFFCHAN_TX_OK, which allows frames to be transmitted
when the queues are stopped only for the off-channel stop reason. Update
all locations transmitting off-channel frames to use this flag.
Signed-off-by: NSeth Forshee <seth.forshee@canonical.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

It's more of an unnecessary micro-optimization and it prevents switching
from long-GI to short-GI in HT20/single-stream for the lowest rate
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When we get to association, the AP station already exists and
is marked authenticated, so moving it into IEEE80211_STA_AUTH
again is a NOP, remove it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Now that we have channel contexts, idle is (pretty
much) equivalent to not having a channel context.
Change the code to use this relation so that there
no longer is a need for a lot of idle recalculate
calls everywhere.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There are only a few drivers that use HW scan, and
all of those don't need a non-idle transition before
starting the scan -- some don't even care about idle
at all. Remove the flag and code associated with it.

The only driver that really actually needed this is
wl1251 and it can just do it itself in the hw_scan
callback -- implement that.
Acked-by: NLuciano Coelho <coelho@ti.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The functions were added for some sort of Bluetooth
coexistence, but aren't used, so remove them again.
Reviewed-by: NLuciano Coelho <coelho@ti.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

In order to be able to predict the next DTIM TBTT
in the driver, add the ability to use timing data
from beacons only with the new hardware flag
IEEE80211_HW_TIMING_BEACON_ONLY and the BSS info
value sync_dtim_count which is only valid if the
timing data came from a beacon. The data can only
come from a beacon, and if no beacon was received
before association it is updated later together
with the DTIM count notification.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

While technically the TSF isn't an IE, it can be
necessary to distinguish between the TSF from a
beacon and a probe response, in particular in
order to know the next DTIM TBTT, as not all APs
are spec compliant wrt. TSF==0 being a DTIM TBTT
and thus the DTIM count needs to be taken into
account as well.

To allow this, move the TSF into the IE struct
so it can be known whence it came.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Add debugfs driver callbacks so drivers can add
debugfs entries for interfaces. Note that they
_must_ remove the entries again as add/remove in
the driver doesn't correspond to add/remove in
debugfs; the former is up/down while the latter
is netdev create/destroy.
Signed-off-by: NAlexander Bondar <alexander.bondar@intel.com>
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Currently the code assigns channel contexts to VLANs
(for use by the TX/RX code) when the AP master gets
its channel context assigned. This works fine, but
in the upcoming radar detection work the VLANs don't
require a channel context (during radar detection)
and assigning one to them anyway causes issues with
locking and also inconsistencies -- a VLAN interface
that is added before radar detection would get the
channel context, while one added during it wouldn't.

Fix these issues moving the channel context copying
to a new explicit operation that will not be used
in the radar detection code.
Acked-by: NSimon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The chandef tracing writes center_freq1 twice, so
that it is always 0 (no driver supports 80+80 yet)
and leaves center_freq2 unset. Fix this mistake.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The messages currently refer to probe request probes,
but on some devices null data packets will be used
instead. Make the messages more generic.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This patch fixes the problem which was discussed in
"mac80211: Fix PN corruption in case of multiple
virtual interface" [1].

Amit Shakya reported a serious issue with my patch:
mac80211: serialize rx path workers" [2]:

In case, ieee80211_rx_handlers processing is going on
for skbs received on one vif and at the same time, rx
aggregation reorder timer expires on another vif then
sta_rx_agg_reorder_timer_expired is invoked and it will
push skbs into the single queue (local->rx_skb_queue).

ieee80211_rx_handlers in the while loop assumes that
the skbs are for the same sdata and sta. This assumption
doesn't hold good in this scenario and the PN gets
corrupted by PN received in other vif's skb, causing
traffic to stop due to PN mismatch."

[1] Message-Id: http://mid.gmane.org/201302041844.44436.chunkeey@googlemail.com
[2] Commit-Id: 24a8fdadReported-by: NAmit Shakya <amit.shakya@stericsson.com>
Signed-off-by: NChristian Lamparter <chunkeey@googlemail.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There seems to be no reason, why it has to be limited to 2.4 GHz.
Signed-off-by: NEmanuel Taube <emanuel.taube@gmail.com>
[remove 'local' variable]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The patch "mac80211: clean up mesh sta allocation warning"
moved some mesh initialization into a path which is only
called when the kernel handles peering. This causes a hang
when mac80211 tries to clean up a userspace-allocated
station entry and delete a timer which has never been
initialized.

To avoid this, only do any mesh sta peering teardown if
the kernel is actually handling it.

The same is true when quiescing before suspend.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

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: NFengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This prepares for using the spinlock instead of krefs
which is needed in the next patch to track the refs
of combined BSSes correctly.

Acked-by: Bing Zhao <bzhao@marvell.com> [mwifiex]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since mesh_plink_quiesce() would unconditionally delete
the plink timer, and the timer initialization was recently
moved into the mesh code path, suspending with a non-mesh
interface now causes a crash. Fix this by only deleting
the plink timer for mesh interfaces.
Reported-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Tested-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

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: NMarco Porsch <marco@cozybit.com>
Signed-off-by: NIvan Bezyazychnyy <ivan.bezyazychnyy@gmail.com>
Signed-off-by: NMike Krinkin <krinkin.m.u@gmail.com>
Signed-off-by: NMax Filippov <jcmvbkbc@gmail.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If the driver determined the connection was lost or that
it couldn't securely maintain the connection when coming
out of WoWLAN, send a deauth frame to the AP to also let
it know.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When we had a connection for WoWLAN and after resume it
needed to be disconnected, the previous commit enabled
sending a deauth frame to the AP. This frame would not
go through on MFP-enabled networks as the key for it is
marked tainted before the frame is transmitted.

Allow a tainted key to be used for deauth frames. Worst
case, we'll use a wrong key because the PTK was rekeyed
while suspended, but more likely the PTK is still fine
and the taint flag really only applies to the GTK(s).
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The ssid/ssid_len fields in the private BSS
struct are unused, contrary to the comment
we do look up the SSID in the few cases we
need it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

With multi-channel, there's a corner case where a driver
doesn't receive a beacon soon enough to be able to sync
its timers with the AP. In this case, the only recovery
(after trying again) is to disconnect from the AP. Allow
calling ieee80211_connection_loss() for such cases. To
make that possible, modify the work function to not rely
on the IEEE80211_HW_CONNECTION_MONITOR flag but use new
state kept in the interface instead.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If the driver determines the connection is lost,
send a deauth frame to the AP anyway just in case
it still considers the connection alive. The frame
might not go through, but at least we've tried.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Patch vastly improve latency while scanning. Slight throughput
improvements were observed as well. Is intended for improve performance
of voice and video applications, when scan is periodically requested by
user space (i.e. default NetworkManager behaviour).

Patch remove latency requirement based on PM_QOS_NETWORK_LATENCY,
this value is 2000 seconds by default (i.e. approximately 0.5 hour !?!).

Also remove listen interval requirement, which based on beaconing and
depending on BSS parameters. It can make we stay off-channel for a
second or more.

Instead try to offer the best latency that we could, i.e. be off-channel
no longer than PASSIVE channel scan time: 125 ms. That mean we will
scan two ACTIVE channels and go back to on-channel, and one PASSIVE
channel, and go back to on-channel.

Patch also decrease PASSIVE channel scan time to about 110 ms.

As drawback patch increase overall scan time. On my tests, when scanning
both 2GHz and 5GHz bands, scanning time increase from 5 seconds up to 10
seconds. Since that increase happen only when we are associated, I think
it can be acceptable. If eventually better scan time is needed for
situations when we lose signal and quickly need to decide to which AP
roam, additional scan flag or parameter can be introduced.

I tested patch by doing:

while true; do iw dev wlan0 scan; sleep 3; done > /dev/null

and

ping -i0.2 -c 1000 HOST

on remote and local machine, results are as below:

* Ping from local periodically scanning machine to AP:
Unpatched: rtt min/avg/max/mdev = 0.928/24.946/182.135/36.873 ms
Patched:   rtt min/avg/max/mdev = 0.928/19.678/150.845/33.130 ms

* Ping from remote machine to periodically scanning machine:
Unpatched: rtt min/avg/max/mdev = 1.637/120.683/709.139/164.337 ms
Patched:   rtt min/avg/max/mdev = 1.807/26.893/201.435/40.284 ms

Throughput measured by scp show following results.

* Upload to periodically scanning machine:
Unpatched: 3.9MB/s   03:15
Patched:   4.3MB/s   02:58

* Download from periodically scanning machine:
Unpatched: 5.5MB/s   02:17
Patched:   6.2MB/s   02:02
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When sending authentication/association frames they
might take a bit of time to go out because we may
have to synchronise with the AP, in particular in
the case where it's really a P2P GO. In this case
the 200ms fixed timeout could potentially be too
short if the beacon interval is relatively large.

For drivers that report TX status we can do better.
Instead of starting the timeout directly, start it
only when the frame status arrives. Since then the
frame was out on the air, we can wait shorter (the
typical response time is supposed to be 30ms, wait
100ms.) Also, if the frame failed to be transmitted
try again right away instead of waiting.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

These pointers/values are never used, remove them.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

We track this, but never use it, so we can
just remove it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Currently, when the driver requires the DTIM period,
mac80211 will wait to hear a beacon before association.
This behavior is suboptimal since some drivers may be
able to deal with knowing the DTIM period after the
association, if they get it at all.

To address this, notify the drivers with bss_info_changed
with the new BSS_CHANGED_DTIM_PERIOD flag when the DTIM
becomes known. This might be when changing to associated,
or later when the entire association was done with only
probe response information.

Rename the hardware flag for the current behaviour to
IEEE80211_HW_NEED_DTIM_BEFORE_ASSOC to more accurately
reflect its behaviour. IEEE80211_HW_NEED_DTIM_PERIOD is
no longer accurate as all drivers get the DTIM period
now, just not before association.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The field is never used, so remove it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When waking up from WoWLAN, it is useful to know
what triggered the wakeup. Support reporting the
wakeup reason(s) in cfg80211 (and a pass-through
in mac80211) to allow userspace to know.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The standard mandates mesh STAs to set the ERP Short Slot
Time capability info bit in beacons to 0. Even though this
is their way of disallowing short slot time for mesh STAs,
there should be no harm in enabling it if we determine all
STAs in the current MBSS support ERP rates.

Increases throughput about 20% for legacy rates when
enabled.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This is basically a revert of:

commit 5b632fe8
Author: Stanislaw Gruszka <sgruszka@redhat.com>
Date:   Mon Dec 3 12:56:33 2012 +0100

    mac80211: introduce IEEE80211_HW_TEARDOWN_AGGR_ON_BAR_FAIL

We do not need this flag any longer, rt2x00 BAR/BA problem was fixed
correctly by wireless-testing commit:

commit 84e9e8eb
Author: Helmut Schaa <helmut.schaa@googlemail.com>
Date:   Thu Jan 17 17:34:32 2013 +0100

    rt2x00: Improve TX status handling for BlockAckReq frames
Signed-off-by: NStanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Before "mac80211: clean up mesh sta allocation warning"
was applied, mesh_sta_info_get() was reshuffled to please
sparse. As a result we neglect to initialize newly created
STAs. Fix this.
Signed-off-by: NThomas Pedersen <thomas@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

gcc cannot prove that the value of sdata->vif.type does not
change between the switch() statement and the second
comparison to NL80211_IFTYPE_AP, causing a harmless
warning.
Slightly reordering the code makes the warning go away
with no functional change.

Without this patch, building ARM at91sam9g45_defconfig with
gcc-4.6 results in:

net/mac80211/tx.c: In function 'ieee80211_subif_start_xmit':
net/mac80211/tx.c:1797:22: warning: 'chanctx_conf' may be used uninitialized in this function [-Wuninitialized]
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: "John W. Linville" <linville@tuxdriver.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: linux-wireless@vger.kernel.org
Cc: netdev@vger.kernel.org
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There's no need to have two checks for "associated"
in ieee80211_sta_restart(), make the first one locked
to not race (unlikely at this point during resume)
and remove the second check.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>