Channels in 2.4GHz band overlap, this means that if we
send a probe request on channel 1 and then move to channel
2, we will hear the probe response on channel 2. In this
case, the RSSI will be lower than if we had heard it on
the channel on which it was sent (1 in this case).

The firmware / low level driver can parse the channel in
the DS IE or HT IE and compensate the RSSI so that it will
still have a valid value even if we heard the frame on an
adjacent channel. This can be done up to a certain offset.

Add this offset as a configuration for the low level driver.
A low level driver that can compensate the low RSSI in this
case should assign the maximal offset for which the RSSI
value is still valid.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Otherwise every "indoor" setting by usermode will cause a regdomain reset.
Acked-by: Luis R. Rodriguez <mcgrof@suse.com>
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Implement and export the new cfg80211_get_station() API.
This utility can be used by other kernel modules to obtain
detailed information about a given wireless station.

It will be in particular useful to batman-adv which will
implement a wireless rate based metric.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add get_expected_throughput() API to mac80211 so that each
driver can implement its own version based on the RC
algorithm they are using (might be using an HW RC algo).
The API returns a value expressed in Kbps.

Also, add the new get_expected_throughput() member
to the rate_control_ops structure in order to be
able to query the RC algorithm (this patch provides an
implementation of this API for both minstrel and
minstrel_ht).

The related member in the station_info object is now
filled accordingly when dumping a station.

Cc: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Users may need information about the expected throughput
towards a given peer.
This value is supposed to consider the size overhead
generated by the 802.11 header.

This value is exported in kbps through the get_station() API
by including it into the station_info object.
Moreover, it is sent to user space when replying to the
nl80211 GET_STATION command.

This information will be useful to the batman-adv module
which will use it for its new metric computation.
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This requires changing the nl80211 parsing code a bit to use
intermediate pointers for the allocation, but clarifies the
API towards the drivers.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This also propagates through the drivers.

The orinoco driver uses the cfg80211 API structs for internal
bookkeeping, and so needs a (void *) cast that removes the
const - but that's OK because it allocates those pointers.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This propagates through all the drivers and mac80211.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The csa_counter_offs was erroneously described as csa_offs in
the docbook section.

This fixes two warnings when making htmldocs (at least):

Warning(include/net/mac80211.h:3428): No description found for parameter 'csa_counter_offs[IEEE80211_MAX_CSA_COUNTERS_NUM]'
Warning(include/net/mac80211.h:3428): Excess struct/union/enum/typedef member 'csa_offs' description in 'ieee80211_mutable_offsets'
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Move the comment in the structure to a description of the
max_num_csa_counters field in the docbook area.

This fixes a warning when building htmldocs (at least):

 Warning(include/net/cfg80211.h:3064): No description found for parameter 'max_num_csa_counters'
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Antonio and I were looking over this code and some things
didn't immediately make sense, so we came up with two small
clarifications.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Make the beacon CSA counters part of ieee80211_mutable_offsets and don't
decrement CSA counters when generating a beacon template. This permits the
driver to offload the CSA counters handling. Since mac80211 updates the probe
responses with the correct counter, the driver should sync the counter's value
with mac80211 using ieee80211_csa_update_counter function.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add a new API ieee80211_beacon_get_template, which doesn't
affect DTIM counter and should be used if the device generates beacon
frames, and new beacon template is needed. In addition set the offsets
to TIM IE for MESH interface.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Support up to IEEE80211_MAX_CSA_COUNTERS_NUM csa counters.
This is defined to be 2 now, to support both CSA and eCSA
counters.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Change the type of NL80211_ATTR_CSA_C_OFF_BEACON and
NL80211_ATTR_CSA_C_OFF_PRESP to be NLA_BINARY which allows
userspace to use beacons and probe responses with
multiple CSA counters.
This isn't breaking the API since userspace can
continue to use nla_put_u16 for this attributes, which
is equivalent to a single element u16 array.
In addition advertise max number of supported CSA counters.
This is needed when using CSA and eCSA IEs together.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Track current csa counter value and use it
to update mgmt frames at the provided offsets.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add NL80211_ATTR_CSA_C_OFFSETS_TX which holds an array
of offsets to the CSA counters which should be updated
when sending a management frames with NL80211_CMD_FRAME.

This API should be used by the drivers that wish to keep the
CSA counter updated in probe responses, but do not implement
probe response offloading and so, do not use
ieee80211_proberesp_get function.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

There is no need to pass NL80211_IFTYPE_UNSPECIFIED when calling
cfg80211_chandef_dfs_required() since we always already have the
interface type.  So, pass the actual interface type instead.

Additionally, have cfg80211_chandef_dfs_required() WARN if the passed
interface type is NL80211_IFTYPE_UNSPECIFIED, so we can detect
problems more easily.
Tested-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Reported-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

After patch:
cfg80211/mac80211: refactor cfg80211_chandef_dfs_required()

start_radar_detection always fail with -EINVAL.
Acked-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

At the moment, the ath9k/ath10k DFS module only supports detecting ETSI
radar patterns.
Add a bitmap in the interface combinations, indicating which DFS regions
are supported by the detector. If unset, support for all regions is
assumed.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When the driver fails during HW restart or resume, the whole
stack goes into a very confused state with interfaces being
up while the hardware is down etc.

Address this by shutting down everything; we'll run into a
lot of warnings in the process but that's better than having
the whole stack get messed up.
Reviewed-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Commit 59af6928 (mac80211: fix CSA tx queue stopping) introduced a
sparse warning:

net/mac80211/cfg.c:3274:5: warning: symbol '__ieee80211_channel_switch' was not declared. Should it be static?

Fix it by declaring the function static.
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

When trying to generate documentation, at least xmldocs, we get the
following warning:

Warning(include/net/cfg80211.h:461): No description found for parameter 'nl80211_iftype'

Fix it by adding the iftype argument name to the
cfg80211_chandef_dfs_required() function declaration.
Reported-and-tested-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

It doesn't make much sense to leave a crippled
interface running.

As a side effect this will unblock tx queues with
CSA reason immediately after failure instead of
until after userspace requests interface to stop.

This also gives userspace an opportunity to
indirectly see CSA failure.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
[small code cleanup]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If gpio controller requires waiting for read and write
GPIO values, then we have to use the gpio cansleep api.
Fix the rfkill_gpio_set_power which calls only the
nonsleep version (causing kernel warning).
There is no problem to use the cansleep version here
because we are not in IRQ handler or similar context
(cf rfkill_set_block).
Signed-off-by: Loic Poulain <loic.poulain@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

It is not guaranteed that multi-vif channel
switching is tightly synchronized. It makes sense
to ignore cqm (missing beacons, et al) while csa
is progressing and re-check it after it completes.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This exports a new cfg80211_stop_iface() function.

This is intended for driver internal interface
combination management and channel switching.

Due to locking issues (it re-enters driver) the
call is asynchronous and uses cfg80211 event
list/worker.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

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

It was possible for tx queues to be stuck stopped
if AP CSA finalization failed. In that case
neither stop_ap nor do_stop woke the queues up.
This means it was impossible to perform tx at all
until driver was reloaded or a successful CSA was
performed later.

It was possible to solve this in a simpler manner
however this is more robust and future proof
(having multi-vif CSA in mind).

New sdata->csa_block_tx is introduced to keep
track of which interfaces requested tx to be
blocked for CSA. This is required because mac80211
stops all tx queues for that purpose. This means
queues must be awoken only when last tx-blocking
CSA interface is finished.

It is still possible to have tx queues stopped
after CSA failure but as soon as offending
interfaces are stopped from userspace (stop_ap or
ifdown) tx queues are woken up properly.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The 'local' variable in __ieee80211_vif_copy_chanctx_to_vlans()
is only used/needed when lockdep is compiled in, mark it as such
to avoid compile warnings in the other case.

While at it, fix some indentation where it's used.
Reviewed-by: Luciano Coelho <luciano.coelho@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

With new additions planned, this code is getting too big for cfg.c.
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Expose a new tdls flag for the public ieee80211_sta struct.
This can be used in some rate control decisions.
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

These BUG_ON statements should never trigger, but in the unlikely
event that somebody does manage don't stop everything but simply
exit the code path with an error.

Leave the one BUG_ON where changing it would result in a NULL
pointer dereference.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

These really can't trigger unless somebody messes up the code,
but don't make debugging it needlessly complicated, WARN and
return instead of BUG_ON().
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

mac80211 takes care of all the needed steps for hwsim, so indicate
support for this capability.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Implement the new cfg80211 capability to enable mac80211-based drivers
to support for dynamic channel bandwidth changes (e.g., HT 20/40 MHz
changes).
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This extends NL80211_CMD_SET_CHANNEL to allow dynamic channel bandwidth
changes in AP mode (including P2P GO) during a lifetime of the BSS. This
can be used to implement, e.g., HT 20/40 MHz co-existence rules on the
2.4 GHz band.
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

P2P_DEVICE doesn't support ieee80211_bss_info_change_notify() for now,
so it's not needed to set changed flags for P2P_DEVICE.
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

ieee80211_assign_chanctx() checks if local->use_chanctx is true, so
the two code block related to ieee80211_assign_chanctx() can be moved
into above if clause, emphasize that these code are executed only if
local->use_chanctx is true.
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
[change subject]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Current code checks if the 20MHz bandwidth is allowed for
particular channel -- if it is not, the channel is disabled.
Since we need to use 5/10 MHz channels, this code is modified in
the way that the default bandwidth to check is 5MHz. If the
maximum bandwidth allowed by the channel is smaller than 5MHz,
the channel is disabled. Otherwise the channel is used and the
flags are set according to the bandwidth allowed by the channel.
Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>