This allows users to disable features such as HT, HT40,
and to modify the MCS, AMPDU, and AMSDU settings for
drivers that support it.

The MCS, AMPDU, and AMSDU features that may be disabled are
are reported in the phy-info netlink message as a mask.

Attemping to disable features that are not supported will
take no affect, but will not return errors.  This is to aid
backwards compatibility in user-space apps that may not be
clever enough to deal with parsing the the capabilities mask.

This patch only enables the infrastructure.  An additional
patch will enable the feature in mac80211.
Signed-off-by: NBen Greear <greearb@candelatech.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

For probe responses it can be useful to not wait for ACK to
avoid retransmissions if the station that sent the probe is
already on the next channel, so allow userspace to request
not caring about the ACK with a new nl80211 flag.

Since mac80211 needs to be updated for the new function
prototype anyway implement it right away -- it's just a
few lines of code.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add the ability to register to received beacon frames
to allow implementing OLBC logic in userspace. The
registration is per wiphy since there's no point in
receiving the same frame multiple times.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add a new nl80211 attribute to specify whether to send the management
frames in CCK rate or not. As of now the wpa_supplicant is disabling
CCK rate at P2P init itself. So this patch helps to send P2P probe
request/probe response/action frames being sent at non CCK rate in 2GHz
without disabling 11b rates.

This attribute is used with NL80211_CMD_TRIGGER_SCAN and
NL80211_CMD_FRAME commands to disable CCK rate for management frame
transmission.

Cc: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NRajkumar Manoharan <rmanohar@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Instead of using a hardcoded list of cipher suites in nl80211.c, use a
shared function in util.c to verify that the driver advertises support
for the specified cipher. This provides more accurate validation of the
values and allows vendor-specific cipher suites to be added in drivers.
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The function wiphy_update_regulatory() uses the static variable
last_request and thus needs to be called with reg_mutex held.
This is the case for all users in reg.c, but the function was
exported for use by wiphy_register(), from where it is called
without the lock being held.

Fix this by making wiphy_update_regulatory() private and introducing
regulatory_update() as a wrapper that acquires and holds the lock.
Signed-off-by: NSven Neumann <s.neumann@raumfeld.com>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: Luis R. Rodriguez <mcgrof@gmail.com>
Cc: Daniel Mack <daniel@zonque.org>
Cc: linux-wireless@vger.kernel.org
Acked-by: NLuis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Some P2P scans are not allowed to advertise
11b rates, but that is a rather special case
so instead of having that, allow userspace
to request the rate sets (per band) that are
advertised in scan probe request frames.

Since it's needed in two places now, factor
out some common code parsing a rate array.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

There was a deadlock when rfkill-blocking a wireless interface,
because we were locking the rdev mutex on NETDEV_GOING_DOWN to stop
sched_scans that were eventually running.  The rfkill block code was
already holding a mutex under rdev:

kernel: =======================================================
kernel: [ INFO: possible circular locking dependency detected ]
kernel: 3.0.0-rc1-00049-g1fa7b6a2 #57
kernel: -------------------------------------------------------
kernel: kworker/0:1/4525 is trying to acquire lock:
kernel: (&rdev->mtx){+.+.+.}, at: [<ffffffff8164c831>] cfg80211_netdev_notifier_call+0x131/0x5b0
kernel:
kernel: but task is already holding lock:
kernel: (&rdev->devlist_mtx){+.+.+.}, at: [<ffffffff8164dcef>] cfg80211_rfkill_set_block+0x4f/0xa0
kernel:
kernel: which lock already depends on the new lock.

To fix this, add a new mutex specifically for sched_scan, to protect
the sched_scan_req element in the rdev struct, instead of using the
global rdev mutex.
Reported-by: NDuane Griffin <duaneg@dghda.com>
Signed-off-by: NLuciano Coelho <coelho@ti.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

cfg80211 scan code adds separate BSS entries if the same BSS shows up
on multiple channels. However, sme implementation does not use the
frequency when fetching the BSS entry. Fix this by adding channel
information to cfg80211_roamed() and include it in cfg80211_get_bss()
calls.

Please note that drivers using cfg80211_roamed() need to be modified to
fully implement this fix. This commit includes only minimal changes to
avoid compilation issues; it maintains the old (broken) behavior for
most drivers. ath6kl was the only one that I could test, so I updated
it to provide the operating frequency in the roamed event.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add the ability to advertise interface combinations in nl80211.
This allows the driver to indicate what the combinations are
that it supports. "Combinations" of just a single interface are
implicit, as previously. Note that cfg80211 will enforce that
the restrictions are met, but not for all drivers yet (once all
drivers are updated, we can remove the flag and enforce for all).

When no combinations are actually supported, an empty list will
be exported so that userspace can know if the kernel exported
this info or not (although it isn't clear to me what tools using
the info should do if the kernel didn't export it).

Since some interface types are purely virtual/software and don't
fit the restrictions, those are exposed in a new list of pure SW
types, not subject to restrictions. This mainly exists to handle
AP-VLAN and monitor interfaces in mac80211.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When sched_scan_stopped was called by the driver, mac80211 calls
cfg80211, which in turn was calling mac80211 back with a flag
"driver_initiated".  This flag was used so that mac80211 would do the
necessary cleanup but would not call the driver.  This was enough to
prevent the bounce back between the driver and mac80211, but not
between mac80211 and cfg80211.

To fix this, we now do the cleanup in mac80211 before calling
cfg80211.  To help with locking issues, the workqueue was moved from
cfg80211 to mac80211.
Reported-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NLuciano Coelho <coelho@ti.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Multiple virtual AP interfaces can currently try
to use different beacon intervals, but that just
leads to problems since it won't actually be done
that way by drivers. Return an error in this case
to make sure it won't be done wrong.

Also, ignore attempts to change the DTIM period
or beacon interval during the lifetime of the BSS.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Implement new functionality for scheduled scan offload.  With this feature we
can scan automatically at certain intervals.

The idea is that the hardware can perform scan automatically and filter on
desired results without waking up the host unnecessarily.

Add NL80211_CMD_START_SCHED_SCAN and NL80211_CMD_STOP_SCHED_SCAN
commands to the nl80211 interface.  When results are available they are
reported by NL80211_CMD_SCHED_SCAN_RESULTS events.  The userspace is
informed when the scheduled scan has stopped with a
NL80211_CMD_SCHED_SCAN_STOPPED event, which can be triggered either by
the driver or by a call to NL80211_CMD_STOP_SCHED_SCAN.
Signed-off-by: NLuciano Coelho <coelho@ti.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This is based on (but now quite far from) the
original work from Luis and Eliad. Add support
for configuring WoWLAN triggers, and getting
the configuration out again. Changes from the
original patchset are too numerous to list,
but one important change needs highlighting:
the suspend() callback is passed NULL for the
trigger configuration if userspace has not
configured WoWLAN at all.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NEliad Peller <eliad@wizery.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Userspace will now be allowed to toggle between the default path
selection algorithm (HWMP, implemented in the kernel), and a vendor
specific alternative.  Also in the same patch, allow userspace to add
information elements to mesh beacons.  This is accordance with the
Extensible Path Selection Framework specified in version 7.0 of the
802.11s draft.
Signed-off-by: NJavier Cardona <javier@cozybit.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Instead of tying mesh activity to interface up,
add join and leave commands for mesh. Since we
must be backward compatible, let cfg80211 handle
joining a mesh if a mesh ID was pre-configured
when the device goes up.

Note that this therefore must modify mac80211 as
well since mac80211 needs to lose the logic to
start the mesh on interface up.

We now allow querying mesh parameters before the
mesh is connected, which simply returns defaults.
Setting them (internally renamed to "update") is
only allowed while connected. Specify them with
the new mesh join command instead where needed.

In mac80211, beaconing must now also follow the
mesh enabled/not enabled state, which is done
by testing the mesh ID.
Signed-off-by: NJavier Cardona <javier@cozybit.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

With p2p, it is sometimes necessary to transmit
a frame (typically an action frame) on another
channel than the current channel. Enable this
through the CMD_FRAME API, and allow it to wait
for a response. A new command allows that wait
to be aborted.

However, allow userspace to specify whether or
not it wants to allow off-channel TX, it may
actually want to use the same channel only.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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

Change "return (EXPR);" to "return EXPR;"

return is not a function, parentheses are not required.
Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Instead of using a WARN_ON(!mutex_is_locked())
use lockdep_assert_held() which compiles away
completely when lockdep isn't enabled, and
also is a more accurate assertion since it
checks that the current thread is holding the
mutex.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Allow userspace to register for more than just
action frames by giving the frame subtype, and
make it possible to use this in various modes
as well.

With some tweaks and some added functionality
this will, in the future, also be usable in AP
mode and be able to replace the cooked monitor
interface currently used in that case.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When sending action frames, we want to verify
that we do that on the correct channel. However,
checking the channel type in addition can get in
the way, since the channel type could change on
the fly during an association, and it's not
useful to have the channel type anyway since it
has no effect on the transmission. Therefore,
make it optional to specify so that if wanted,
it can still be checked, but is not required.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Currently (all tested with hwsim) you can do stupid
things like setting up an AP on a certain channel,
then adding another virtual interface and making
that associate on another channel -- this will make
the beaconing to move channel but obviously without
the necessary IEs data update.

In order to improve this situation, first make the
configuration APIs (cfg80211 and nl80211) aware of
multi-channel operation -- we'll eventually need
that in the future anyway. There's one userland API
change and one API addition. The API change is that
now SET_WIPHY must be called with virtual interface
index rather than only wiphy index in order to take
effect for that interface -- luckily all current
users (hostapd) do that. For monitor interfaces, the
old setting is preserved, but monitors are always
slaved to other devices anyway so no guarantees.

The second userland API change is the introduction
of a per virtual interface SET_CHANNEL command, that
hostapd should use going forward to make it easier
to understand what's going on (it can automatically
detect a kernel with this command).

Other than mac80211, no existing cfg80211 drivers
are affected by this change because they only allow
a single virtual interface.

mac80211, however, now needs to be aware that the
channel settings are per interface now, and needs
to disallow (for now) real multi-channel operation,
which is another important part of this patch.

One of the immediate benefits is that you can now
start hostapd to operate on a hardware that already
has a connection on another virtual interface, as
long as you specify the same channel.

Note that two things are left unhandled (this is an
improvement -- not a complete fix):

 * different HT/no-HT modes

   currently you could start an HT AP and then
   connect to a non-HT network on the same channel
   which would configure the hardware for no HT;
   that can be fixed fairly easily

 * CSA

   An AP we're connected to on a virtual interface
   might indicate switching channels, and in that
   case we would follow it, regardless of how many
   other interfaces are operating; this requires
   more effort to fix but is pretty rare after all
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

cfg80211 is quite strict on allowing authentication and association
commands only in certain states. In order to meet these requirements,
user space applications may need to clear authentication or
association state in some cases. Currently, this can be done with
deauth/disassoc command, but that ends up sending out Deauthentication
or Disassociation frame unnecessarily. Add a new nl80211 attribute to
allow this sending of the frame be skipped, but with all other
deauth/disassoc operations being completed.

Similar state change is also needed for IEEE 802.11r FT protocol in
the FT-over-DS case which does not use Authentication frame exchange
in a transition to another BSS. For this to work with cfg80211, an
authentication entry needs to be created for the target BSS without
sending out an Authentication frame. The nl80211 authentication
command can be used for this purpose, too, with the new attribute to
indicate that the command is only for changing local state. This
enables wpa_supplicant to complete FT-over-DS transition successfully.
Signed-off-by: NJouni Malinen <j@w1.fi>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This implements a new command to register for action frames
that userspace wants to handle instead of the in-kernel
rejection. It is then responsible for rejecting ones that
it decided not to handle. There is no unregistration, but
the socket can be closed for that.

Frames that are not registered for will not be forwarded
to userspace and will be rejected by the kernel, the
cfg80211 API helps implementing that.

Additionally, this patch adds a new command that allows
doing action frame transmission from userspace. It can be
used either to exchange action frames on the current
operational channel (e.g., with the AP with which we are
currently associated) or to exchange off-channel Public
Action frames with the remain-on-channel command.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Future code will need to look up rdev and wdev
within atomic sections, but currently we need
to lock a mutex for such lookups. Change the
list handling for both to be RCU-safe so that
we can look them up in rcu sections instead in
the future.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Store information elements from Beacon and Probe Response frames in
separate buffers to allow both sets to be made available through
nl80211. This allows user space applications to get access to IEs from
Beacon frames even if we have received Probe Response frames from the
BSS. Previously, the IEs from Probe Response frames would have
overridden the IEs from Beacon frames.

This feature is of somewhat limited use since most protocols include
the same (or extended) information in Probe Response frames. However,
there are couple of exceptions where the IEs from Beacon frames could
be of some use: TIM IE is only included in Beacon frames (and it would
be needed to figure out the DTIM period used in the BSS) and at least
some implementations of Wireless Provisioning Services seem to include
the full IE only in Beacon frames).

The new BSS attribute for scan results is added to allow both the IE
sets to be delivered. This is done in a way that maintains the
previously used behavior for applications that are not aware of the
new NL80211_BSS_BEACON_IES attribute.
Signed-off-by: NJouni Malinen <j@w1.fi>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add new commands for requesting the driver to remain awake
on a specified channel for the specified amount of time
(and another command to cancel such an operation). This
can be used to implement userspace-controlled off-channel
operations, like Public Action frame exchange on another
channel than the operation channel.

The off-channel operation should behave similarly to scan,
i.e. the local station (if associated) moves into power
save mode to request the AP to buffer frames for it and
then moves to the other channel to allow the off-channel
operation to be completed. The duration parameter can be
used to request enough time to receive a response from
the target station.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Previously, cfg80211 had reported "0" for MCS (i.e. 802.11n) bitrates
through the wireless extensions interface.  However, nl80211 was
converting MCS rates into a reasonable bitrate number.  This patch moves
the nl80211 code to cfg80211 where it is now shared between both the
nl80211 interface and the wireless extensions interface.
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch moves the works cleanup, scan and events to a cfg80211
dedicated workqueue.

Platform driver like eeepc-laptop ought to use works to rfkill (as
new rfkill does lock in rfkill_unregister and the platform driver is
called from rfkill_switch_all which also lock the same mutex).
This raise a new issue in itself that the work scheduled by the platform
driver to the global worqueue calls wiphy_unregister which flush_work
scan and event works (which thus flush works on the global workqueue inside
a work on the global workqueue) and also put on hold the  wdev_cleanup_work
 (which prevents the dev_put on netdev thus indefinite Usage count error on
wifi device).
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NAlban Browaeys <prahal@yahoo.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When going from/to a WEP protected IBSS, we need to
leave this one and join a new one to take care of
the changed capability.

Cc: Hong Zhang <henryzhang62@yahoo.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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

When the in-kernel SME gets an association failure from
the AP we don't deauthenticate, and thus get into a very
confused state which will lead to warnings later on. Fix
this by actually deauthenticating when the AP indicates
an association failure.

(Brought to you by the hacking session at Kernel Summit 2009 in Tokyo,
Japan. -- JWL)
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the interface type changes while connected, and the
driver does not require the interface to be down for a
type change, it is currently possible to get very strange
results unless the driver takes special care, which it
shouldn't have to.

To fix this, take care to disconnect/leave IBSS when
changing the interface type -- even if the driver may fail
the call. Also process all events that may be pending to
avoid running into a situation where an event is reported
but only processed after the type has already changed,
which would lead to missing events and warnings.

A side effect of this is that you will have disconnected
or left the IBSS even if the mode change ultimately fails,
but since the intention was to change it and thus leave or
disconnect, this is not a problem.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Bob reported that he got warnings in IBSS mode about
the ssid_len being zero on a joined event, but only
when kmemcheck was enabled. This appears to be due
to a race condition between drivers and userspace,
when the driver reports joined but the user in the
meantime decided to leave the IBSS again, the warning
would trigger. This was made more likely by kmemcheck
delaying the code that does the check and sends the
event.

So first, make the warning trigger closer to the
driver, which means it's not locked, but since only
the warning depends on it that's ok.

And secondly, users will not want to have spurious
warnings at all, so make those that are known to be
racy in such a way configurable.
Reported-by: NBob Copeland <me@bobcopeland.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When we lose a scan, cfg80211 tries to clean up after
the driver. However, it currently does this too early,
it does this in GOING_DOWN already instead of DOWN, so
it may happen with mac80211. Besides fixing this, also
make it more robust by leaking the scan request so if
the driver later actually finishes the scan, it won't
crash. Also check in ___cfg80211_scan_done whether a
scan request is still pending and exit if not.
Reported-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Tested-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

My patch "cfg80211: fix deadlock" broke the code it
was supposed to fix, the scan request checking. But
it's not trivial to put it back the way it was, since
the original patch had a deadlock.

Now do it in a completely new way: queue the check
off to a work struct, where we can freely lock. But
that has some more complications, like needing to
wait for it to be done before the wiphy/rdev can be
destroyed, so some code is required to handle that.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

If you trigger a scan request on an interface and then
take it down, or rmmod the module or unplug the device
the driver might "forget" to cancel the scan request.
That is a bug in the driver, but the current behaviour
is that we just hang endlessly waiting for the netdev
refcount to become 0 which it never will. To improve
robustness, check for this situation in cfg80211, warn
about it and clean up behind the driver. I don't just
clean up silently because it's likely that the driver
also has some internal state it has now leaked.

Additionally, this fixes a locking bug, clearing the
scan_req pointer should be done under the rdev lock.

Finally, we also need to _wait_ for the scan work and
not just abort it since it might be pending and wanting
to do a cleanup.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

"cfg80211: validate channel settings across interfaces"
contained a locking bug -- in the managed-mode SIWFREQ
call it would end up running into a lock recursion.

This fixes it by not checking that particular interface
for a channel that it needs to stay on, which is as it
should be as that's the interface we're setting the
channel for.
Reported-by: NReinette Chatre <reinette.chatre@intel.com>
Reported-by: NKalle Valo <kalle.valo@iki.fi>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Tested-by: NKalle Valo <kalle.valo@iki.fi>
Tested-by: NReinette Chatre <reinette.chatre@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In order for userspace to be able to figure out whether
it obtained a consistent snapshot of data or not when
using netlink dumps, we need to have a generation number
in each dump message that indicates whether the list has
changed or not -- its value is arbitrary.

This patch adds such a number to all dumps, this needs
some mac80211 involvement to keep track of a generation
number to start with when adding/removing mesh paths or
stations.

The wiphy and netdev lists can be fully handled within
cfg80211, of course, but generation numbers need to be
stored there as well.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>