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>

Add inline wrappers for the BSS struct krefs
to be able to extend them easily later.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This local variable is only used once, so remove it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Instead of annotating with a comment, add a lockdep
annotation which also serves as documentation.
Signed-off-by: Johannes 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: Johannes 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: Johannes Berg <johannes.berg@intel.com>

There's no reason for it to require external
locking, move it into the function.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The comment about allocating the IEs together with
the BSS struct is no longer true, remove it. Also
fix a typo in the same area.
Signed-off-by: Johannes 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: Johannes Berg <johannes.berg@intel.com>

As Thomas pointed out, cfg80211_get_mesh() is
unused and can be removed.

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

Instead of first checking if a BSS is an MBSS
and then doing the comparisons, inline it all
into the BSS comparison function. This avoids
doing the IE searches twice and is also a lot
less code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When trying to find a hidden SSID, the lookup function
is done wrong; the code is trying to combine the two
lookups into one, and as a consequence doesn't always
find the entry at all. To understand this, consider a
case where multiple BSS entries with the same channel
and BSSID exist but have different SSID length. Then
comparing against the probe response SSID length is
bound to cause problems since the hidden one might be
either zeroed out or zero-length.

To fix this we need to do two lookups for the two ways
to hide SSIDs.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Instead of duplicating the rbtree functions, pass
an argument to the compare function. This removes
the code duplication for the two searches.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

In per-station statistics, present 32bit counters are too small
for practical purposes - with gigabit speeds, it get overlapped
every few seconds.

Expand counters in the struct station_info to be 64-bit.
Driver can still fill only 32-bit and indicate in @filled
only bits like STATION_INFO_[TR]X_BYTES; in case driver provides
full 64-bit counter, it should also set in @filled
bit STATION_INFO_[TR]RX_BYTES64

Netlink sends both 32-bit and 64-bit counters, if present, to not
break userspace.
Signed-off-by: Vladimir Kondratiev <qca_vkondrat@qca.qualcomm.com>
[change to also have 32-bit counters if driver advertises 64-bit]
Signed-off-by: Johannes 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: Johannes 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: Johannes 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: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes 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: Johannes Berg <johannes.berg@intel.com>

Now that mac80211 no longer uses this API, remove
it completely. If anyone needs it again, we can
revert this patch of course, but mac80211 was the
only user right now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

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

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

The field is never used, so remove it.
Signed-off-by: Johannes 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: Johannes 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: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The warning here occasionally triggers but we haven't
found the cause yet. It's a valid warning since if it
triggers the SME state got confused, so add the SME
state to it to help narrow it down in the future.
Signed-off-by: Johannes 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: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Conflicts:
	drivers/net/wireless/ath/ath9k/main.c
	drivers/net/wireless/iwlwifi/dvm/tx.c

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

Add API to enable drivers to implement MAC address based
access control in AP/P2P GO mode. Capable drivers advertise
this capability by setting the maximum number of MAC
addresses in such a list in wiphy->max_acl_mac_addrs.

An initial ACL may be given to the NL80211_CMD_START_AP
command and/or changed later with NL80211_CMD_SET_MAC_ACL.

Black- and whitelists are supported, but not simultaneously.
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
[rewrite commit log, many cleanups]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

struct mac_address will be used by ACL related configuration ops.
Signed-off-by: Vasanthakumar Thiagarajan <vthiagar@qca.qualcomm.com>
Signed-off-by: Johannes 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: Arnd 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: Johannes 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: Johannes Berg <johannes.berg@intel.com>

In commit "cfg80211: check radar interface combinations" a regression
was introduced which might lead to NULL dereference if the argument
chan = NULL, which might happen in IBSS/wext case (and probably
others).
Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

An existing mesh station entry may change its rate
capabilities, so call rate_control_rate_update() to notify
the rate control.
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
[fix compilation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This refactoring fixes a "scheduling while atomic" warning
when allocating a mesh station entry while holding the RCU
read lock. Fix this by creating a new function
mesh_sta_info_get(), which correctly handles the locking
and returns under RCU.

Also move some unnecessarily #ifdefed mesh station init
code from sta_info_alloc() to __mesh_sta_info_alloc().
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
[change code flow to make sparse happy]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Reference: IEEE 802.11-2012 8.4.2.27.3 "AKM suites"
Signed-off-by: Bing Zhao <bzhao@marvell.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For drivers that don't actually flush their queues when
aggregation stop with the IEEE80211_AMPDU_TX_STOP_FLUSH
or IEEE80211_AMPDU_TX_STOP_FLUSH_CONT reasons is done,
like iwlwifi or iwlegacy, mac80211 can then transmit on
a TID that the driver still considers busy. This happens
in the following way:

 - IEEE80211_AMPDU_TX_STOP_FLUSH requested
 - driver marks TID as emptying
 - mac80211 removes tid_tx data, this can copy packets
   to the TX pending queues and also let new packets
   through to the driver
 - driver gets unexpected TX as it wasn't completely
   converted to the new API

In iwlwifi, this lead to the following warning:

WARNING: at drivers/net/wireless/iwlwifi/dvm/tx.c:442 iwlagn_tx_skb+0xc47/0xce0
Tx while agg.state = 4
Modules linked in: [...]
Pid: 0, comm: kworker/0:0 Tainted: G        W   3.1.0 #1
Call Trace:
 [<c1046e42>] warn_slowpath_common+0x72/0xa0
 [<c1046f13>] warn_slowpath_fmt+0x33/0x40
 [<fddffa17>] iwlagn_tx_skb+0xc47/0xce0 [iwldvm]
 [<fddfcaa3>] iwlagn_mac_tx+0x23/0x40 [iwldvm]
 [<fd8c98b6>] __ieee80211_tx+0xf6/0x3c0 [mac80211]
 [<fd8cbe00>] ieee80211_tx+0xd0/0x100 [mac80211]
 [<fd8cc176>] ieee80211_xmit+0x96/0xe0 [mac80211]
 [<fd8cc578>] ieee80211_subif_start_xmit+0x348/0xc80 [mac80211]
 [<c1445207>] dev_hard_start_xmit+0x337/0x6d0
 [<c145eee9>] sch_direct_xmit+0xa9/0x210
 [<c14462c0>] dev_queue_xmit+0x1b0/0x8e0

Fortunately, solving this problem is easy as the station
is being destroyed, so such transmit packets can only
happen due to races. Instead of trying to close the race
just let the race not reach the drivers by making two
changes:
 1) remove the explicit aggregation session teardown in
    the managed mode code, the same thing will be done
    when the station is removed, in __sta_info_destroy.
 2) When aggregation stop with AGG_STOP_DESTROY_STA is
    requested, leave the tid_tx data around as stopped.
    It will be cleared and freed in cleanup_single_sta
    later, but until then any racy packets will be put
    onto the tid_tx pending queue instead of transmitted
    which is fine since the station is being removed.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Since drivers can support several BSS / P2P Client
interfaces, the rssi callback needs to inform the driver
about the interface teh rssi event relates to.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>