Commit Graph

187 Commits

Author SHA1 Message Date
Simon Wunderlich 7ca15a0ae8 mac80211: allow scanning for 5/10 MHz channels in IBSS
Use a chandef instead of just the channel for scanning, and enable
5/10 Mhz scanning for IBSS mode. Also reporting is changed to the new
inform_bss functions.

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
2013-07-16 09:58:09 +03:00
Simon Wunderlich 2103dec147 mac80211: select and adjust bitrates according to channel mode
The various components accessing the bitrates table must use consider
the used channel bandwidth to select only available rates or calculate
the bitrate correctly.

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

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Mathias Kretschmer <mathias.kretschmer@fokus.fraunhofer.de>
[make rate unsigned in ieee80211_add_tx_radiotap_header(), squash fix]
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
2013-07-16 09:58:06 +03:00
Alexander Bondar 817cee7675 mac80211: track AP's beacon rate and give it to the driver
Track the AP's beacon rate in the scan BSS data and in the
interface configuration to let the drivers know which rate
the AP is using. This information may be used by drivers,
in our case to let the firmware optimise beacon RX.

Signed-off-by: Alexander Bondar <alexander.bondar@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-06-13 11:58:47 +02:00
Johannes Berg b2e506bfc4 mac80211: parse VHT channel switch IEs
VHT introduces multiple IEs that need to be parsed for a
wide bandwidth channel switch. Two are (currently) needed
in mac80211:
 * wide bandwidth channel switch element
 * channel switch wrapper element

The former is contained in the latter for beacons and probe
responses, but not for the spectrum management action frames
so the IE parser needs a new argument to differentiate them.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-04-16 15:29:45 +02:00
Johannes Berg 1946bed957 mac80211: check ERP info IE length in parser
It's always just one byte, so check for that and
remove the length field from the parser struct.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-04-08 09:16:57 +02:00
Karl Beldan 675a0b049a mac80211: Use a cfg80211_chan_def in ieee80211_hw_conf_chan
Drivers that don't use chanctxes cannot perform VHT association because
they still use a "backward compatibility" pair of {ieee80211_channel,
nl80211_channel_type} in ieee80211_conf and ieee80211_local.

Signed-off-by: Karl Beldan <karl.beldan@rivierawaves.com>
[fix kernel-doc]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-03-25 19:19:35 +01:00
Johannes Berg 39ecc01d1b mac80211: pass queue bitmap to flush operation
There are a number of situations in which mac80211 only
really needs to flush queues for one virtual interface,
and in fact during this frames might be transmitted on
other virtual interfaces. Calculate and pass a queue
bitmap to the driver so it knows which queues to flush.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-03-18 20:15:03 +01:00
Johannes Berg 511044ea0b mac80211: remove a few set but unused variables
Found by compiling with W=1.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-03-11 15:16:42 +02:00
Simon Wunderlich 164eb02d07 mac80211: add radar detection command/event
Add command to trigger radar detection in the driver/FW.
Once radar detection is started it should continuously
monitor for radars as long as the channel active.
If radar is detected usermode notified with 'radar
detected' event.

Scanning and remain on channel functionality must be disabled
while doing radar detection/scanning, and vice versa.

Based on original patch by Victor Goldenshtein <victorg@ti.com>

Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-02-15 09:41:04 +01:00
Seth Forshee 9c35d7d236 mac80211: Add flushes before going off-channel
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: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-02-11 22:52:21 +01:00
Seth Forshee 6c17b77b67 mac80211: Fix tx queue handling during scans
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: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-02-11 22:52:21 +01:00
Johannes Berg ef429dadf3 mac80211: introduce beacon-only timing data
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: Johannes Berg <johannes.berg@intel.com>
2013-02-11 18:45:00 +01:00
Johannes Berg 5b112d3d09 cfg80211: pass wiphy to cfg80211_ref_bss/put_bss
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: Johannes Berg <johannes.berg@intel.com>
2013-02-11 18:44:52 +01:00
Stanislaw Gruszka 3f892b61a8 mac80211: improve latency and throughput while software scanning
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>
2013-01-31 16:45:05 +01:00
Johannes Berg 1672c0e319 mac80211: start auth/assoc timeout on frame status
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>
2013-01-31 14:28:43 +01:00
Johannes Berg 0fe20add2c mac80211: remove unused mesh data from bss
These pointers/values are never used, remove them.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-01-31 14:07:14 +01:00
Johannes Berg ce9877c0cd mac80211: remove last_probe_resp from bss
We track this, but never use it, so we can
just remove it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-01-31 14:06:32 +01:00
John W. Linville 9ebea3829f Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
Conflicts:
	drivers/net/wireless/ath/ath9k/main.c
	drivers/net/wireless/iwlwifi/dvm/tx.c
2013-01-28 13:54:03 -05:00
Stanislaw Gruszka aacde9ee45 mac80211: synchronize scan off/on-channel and PS states
Since:

commit b23b025fe2
Author: Ben Greear <greearb@candelatech.com>
Date:   Fri Feb 4 11:54:17 2011 -0800

    mac80211: Optimize scans on current operating channel.

we do not disable PS while going back to operational channel (on
ieee80211_scan_state_suspend) and deffer that until scan finish.
But since we are allowed to send frames, we can send a frame to AP
without PM bit set, so disable PS on AP side. Then when we switch
to off-channel (in ieee80211_scan_state_resume) we do not enable PS.
Hence we are off-channel with PS disabled, frames are not buffered
by AP.

To fix remove offchannel_ps_disable argument and always enable PS when
going off-channel and disable it when going on-channel, like it was
before.

Cc: stable@vger.kernel.org # 2.6.39+
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Tested-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-01-16 15:06:18 +01:00
Emmanuel Grumbach d45c41722a mac82011: use frame control to differentiate probe resp/beacon
The probe response/beacon management frame RX code passes a
bool parameter to differentiate beacons and probe responses.
This is useless since we have the frame and can thus use its
frame control field. Moreover it is buggy since there is one
call to ieee80211_rx_bss_info with a beacon frame that is
indicated as a probe response, which is also fixed by using
the frame control field, so do that.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-01-03 13:01:33 +01:00
Johannes Berg 826262c3d2 mac80211: fix dtim_period in hidden SSID AP association
When AP's SSID is hidden the BSS can appear several times in
cfg80211's BSS list: once with a zero-length SSID that comes
from the beacon, and once for each SSID from probe reponses.

Since the mac80211 stores its data in ieee80211_bss which
is embedded into cfg80211_bss, mac80211's data will be
duplicated too.

This becomes a problem when a driver needs the dtim_period
since this data exists only in the beacon's instance in
cfg80211 bss table which isn't the instance that is used
when associating.

Remove the DTIM period from the BSS table and track it
explicitly to avoid this problem.

Cc: stable@vger.kernel.org
Tested-by: Efi Tubul <efi.tubul@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-01-03 13:00:00 +01:00
Stanislaw Gruszka 34bcf71502 mac80211: fix ibss scanning
Do not scan on no-IBSS and disabled channels in IBSS mode. Doing this
can trigger Microcode errors on iwlwifi and iwlegacy drivers.

Also rename ieee80211_request_internal_scan() function since it is only
used in IBSS mode and simplify calling it from ieee80211_sta_find_ibss().

This patch should address:
https://bugzilla.redhat.com/show_bug.cgi?id=883414
https://bugzilla.kernel.org/show_bug.cgi?id=49411

Reported-by: Jesse Kahtava <jesse_kahtava@f-m.fm>
Reported-by: Mikko Rapeli  <mikko.rapeli@iki.fi>
Cc: stable@vger.kernel.org
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2013-01-03 12:59:57 +01:00
John W. Linville c66cfd5325 Merge branch 'for-john' of git://git.sipsolutions.net/mac80211-next 2012-12-11 16:04:03 -05:00
Johannes Berg 8e3c1b7743 mac80211: a few whitespace fixes
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-12-10 21:24:02 +01:00
John W. Linville 403e16731f Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Conflicts:
	drivers/net/wireless/mwifiex/sta_ioctl.c
	net/mac80211/scan.c
2012-12-06 14:58:41 -05:00
Johannes Berg c604b9f219 mac80211: make ieee80211_build_preq_ies safer
Instead of assuming 200 bytes are always enough for
all the IEs we add, give the length of the buffer
to the function and warn instead of overrunning.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-11-30 13:41:26 +01:00
John W. Linville 62c8003ecb Merge branch 'for-john' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next 2012-11-26 14:46:41 -05:00
Johannes Berg 0172bb7507 cfg80211: use DS or HT operation IEs to determine BSS channel
Currently, mac80211 checks the DS params IE if present and
uses it for the (primary) BSS channel, instead of the one
that the frame was received on. This is particularly useful
in the 2.4 GHz band since a frame is often received on one
of the adjacent channels due to overlap.

Move this code to cfg80211 so other drivers also do this.

Additionally, on 5 GHz, in particular with some (possibly)
upcoming changes in 802.11ai and duplicate transmissions
when wider channels are used, something similar happens.
So if present, also use the (primary) channel information
contained in the HT operation IE.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-11-23 14:23:30 +01:00
John W. Linville b311749477 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless
Conflicts:
	drivers/net/wireless/brcm80211/brcmfmac/wl_cfg80211.c
	drivers/net/wireless/iwlwifi/pcie/tx.c
2012-11-21 12:57:56 -05:00
David Spinadel bca1e29fb5 mac80211: init sched_scan_ies
In case that there is an unsupported band, the ie will be
unallocated and the free will crash.

Cc: stable@vger.kernel.org
Signed-off-by: David Spinadel <david.spinadel@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-10-31 17:04:18 +01:00
Sam Leffler cd2bb512cd mac80211: add support for tx to abort low priority scan requests
Use NL80211_SCAN_FLAG_LOW_PRIORITY flag in mac80211's scan state
machine to prematurely terminate scan operations if outbound
traffic collides. This is useful for marking background scans so
they don't affect throughput.

Signed-off-by: Sam Leffler <sleffler@chromium.org>
Signed-off-by: Amitkumar Karwar <akarwar@marvell.com>
Signed-off-by: Bing Zhao <bzhao@marvell.com>
[set feature flag only if software scan is used]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-10-18 09:01:53 +02:00
Johannes Berg 55de908ab2 mac80211: use channel contexts
Instead of operating on a single channel only,
use the new channel context infrastructure in
all mac80211 code.

This enables drivers that want to use the new
channel context infrastructure to use multiple
channels, while nothing should change for all
the other drivers that don't support it.

Right now this disables both TX power settings
and spatial multiplexing powersave. Both need
to be re-enabled on a channel context basis.

Additionally, when channel contexts are used
drop the connection when channel switch is
received rather than trying to handle it. This
will have to be improved later.

[With fixes from Eliad and Emmanuel incorporated]
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-10-17 11:02:09 +02:00
Johannes Berg fe57d9f5c0 mac80211: track whether to use channel contexts
Depending on the driver, channel contexts may be used or
not. If they are used, the driver must have support for
hardware scan and remain-on-channel; otherwise the driver
must not advertise support for multiple channels.

Also prohibit WDS type interfaces when channel contexts
are to be used as there's no clear definition of which
channel they use.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-10-16 20:22:46 +02:00
Peter Senna Tschudin 316b6b5df7 net/mac80211/scan.c: removes unnecessary semicolon
removes unnecessary semicolon

Found by Coccinelle: http://coccinelle.lip6.fr/

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-09-07 13:30:06 +02:00
Johannes Berg 30dd3edf97 mac80211: don't hang on to sched_scan_ies
There's no need to keep a copy of the scheduled
scan IEs after the driver has been told, if it
requires a copy it must make one. Therefore, we
can move sched_scan_ies into the function.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-09-06 15:56:35 +02:00
Johannes Berg 944b9e375d Merge remote-tracking branch 'mac80211/master' into mac80211-next
Pull in mac80211.git to let the next patch apply
without conflicts, also resolving a hwsim conflict.

Conflicts:
	drivers/net/wireless/mac80211_hwsim.c

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-09-06 15:56:02 +02:00
Johannes Berg fe94fe05e9 mac80211: pass channel to ieee80211_send_probe_req
In multi-channel scenarios, the channel that we will
transmit a probe request on isn't always the current
channel (which will be NULL anyway) but will instead
be the channel that the AP is on. Pass the channel
to the ieee80211_send_probe_req() function so it can
be used in the different scenarios. The scan code
continues to pass the current channel, of course.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-08-20 14:13:45 +02:00
Johannes Berg 9b86487043 mac80211: check operating channel in scan
The optimisation of scanning only on the current
channel should check the operating channel. Also
modify it to compare channel pointer rather than
the frequency.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-08-20 14:13:43 +02:00
Eliad Peller ba846a502c mac80211: don't clear sched_scan_sdata on sched scan stop request
ieee80211_request_sched_scan_stop() cleared
local->sched_scan_sdata. However, sched_scan_sdata
should be cleared only after the driver calls
ieee80211_sched_scan_stopped() (like with normal hw scan).

Clearing sched_scan_sdata too early caused
ieee80211_sched_scan_stopped_work to exit prematurely
without properly cleaning all the sched scan resources
and without calling cfg80211_sched_scan_stopped (so
userspace wasn't notified about sched scan completion).

Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-30 09:14:36 +02:00
Johannes Berg fcb06702f0 Merge remote-tracking branch 'wireless/master' into mac80211 2012-07-30 09:13:03 +02:00
Johannes Berg 3aa569c3fe mac80211: fix scan_sdata assignment
We need to use RCU to assign scan_sdata.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-24 16:54:11 +02:00
John W. Linville 90b90f60c4 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2012-07-20 12:30:48 -04:00
Johannes Berg 8c358bcd09 mac80211: add time synchronisation with BSS for assoc
Some drivers (iwlegacy, iwlwifi and rt2x00) today use the
bss_conf.last_tsf value. By itself though that value is
completely worthless since it may be ancient. What really
is needed is synchronisation between some device time and
the TSF.

To clarify this, rename bss_conf.last_tsf to sync_tsf and
add sync_device_ts which is obtained from rx_status which
gets a new field device_timestamp for this purpose. This
is intentionally not using the mactime field since that
is used for other things and in IBSS is expected to sync
with the IBSS's TSF which isn't necessarily true for the
device timestamp.

Also, since we have the information and it's useful even
before the connection has been established, give all the
timing details to the driver before authenticating.

Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-12 12:10:46 +02:00
Johannes Berg d48b296850 mac80211: redesign scan RX
Scan receive is rather inefficient when there are
multiple virtual interfaces. We iterate all of the
virtual interfaces and then notify cfg80211 about
each beacon many times.

Redesign scan RX to happen before everything else.
Then we can also get rid of IEEE80211_RX_IN_SCAN
since we don't have to accept frames into the RX
handlers for scanning or scheduled scanning any
more. Overall, this simplifies the code.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-12 12:10:44 +02:00
Johannes Berg 5260a5b2c3 mac80211: track scheduled scan virtual interface
Instead of tracking whether or not we're in a
scheduled scan, track the virtual interface
(sdata) in an RCU-protected pointer to make it
usable from RX to check the MAC address.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-12 12:10:43 +02:00
Johannes Berg e2fd5dbc1c mac80211: make scan_sdata pointer usable with RCU
Making the scan_sdata pointer usable with RCU makes
it possible to dereference it in the RX path to see
if a received frame actually matches the interface
that is scanning. This is just preparations, making
the pointer __rcu.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-12 12:10:43 +02:00
Arik Nemtsov d811b3d556 mac80211: fix invalid band deref building preq IEs
The function building probe-request IEs does not validate the band is
supported before dereferencing it. This can result in a panic when
all bands are traversed, as done during sched-scan start.

Warn when this happens and return an empty probe request. Also fix
sched-scan to not waste memory on unsupported bands.

Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2012-07-12 12:10:42 +02:00
John W. Linville 0440507bbc Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next into for-davem 2012-06-12 14:25:04 -04:00
Johannes Berg 2eb278e083 mac80211: unify SW/offload remain-on-channel
Redesign all the off-channel code, getting rid of
the generic off-channel work concept, replacing
it with a simple remain-on-channel list.

This fixes a number of small issues with the ROC
implementation:
 * offloaded remain-on-channel couldn't be queued,
   now we can queue it as well, if needed
 * in iwlwifi (the only user) offloaded ROC is
   mutually exclusive with scanning, use the new
   queue to handle that case -- I expect that it
   will later depend on a HW flag

The bigger issue though is that there's a bad bug
in the current implementation: if we get a mgmt
TX request while HW roc is active, and this new
request has a wait time, we actually schedule a
software ROC instead since we can't guarantee the
existing offloaded ROC will still be that long.
To fix this, the queuing mechanism was needed.

The queuing mechanism for offloaded ROC isn't yet
optimal, ideally we should add API to have the HW
extend the ROC if needed. We could add that later
but for now use a software implementation.

Overall, this unifies the behaviour between the
offloaded and software-implemented case as much
as possible.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-06-06 15:31:18 -04:00
Joe Perches e3192690a3 net: Remove casts to same type
Adding casts of objects to the same type is unnecessary
and confusing for a human reader.

For example, this cast:

	int y;
	int *p = (int *)&y;

I used the coccinelle script below to find and remove these
unnecessary casts.  I manually removed the conversions this
script produces of casts with __force and __user.

@@
type T;
T *p;
@@

-	(T *)p
+	p

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-06-04 11:45:11 -04:00