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>

Since there are frequency bands (e.g. 5.9GHz) allowing channels
with only 10 or 5 MHz bandwidth, this patch adds attributes that
allow keeping track about this information.

When channel attributes are reported to user-space, make sure to
not break old tools, i.e. if the 'split wiphy dump' is enabled,
report the extra attributes (if present) describing the bandwidth
restrictions.  If the 'split wiphy dump' is not enabled,
completely omit those channels that have flags set to either
IEEE80211_CHAN_NO_10MHZ or IEEE80211_CHAN_NO_20MHZ.

Add the check for new bandwidth restriction flags in
cfg80211_chandef_usable() to comply with the restrictions.
Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Return NOTIFY_DONE if we don't care this time's notification, return
NOTIFY_OK if we successfully handled this time's notification. That's
the formal way to do it.
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Return NOTIFY_DONE if we don't care this time's notification, return
NOTIFY_OK if we successfully handled this time's notification. That's
the formal way to do it.
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Name wiphy_to_rdev is more accurate to describe what the function
does, i.e., return a pointer pointing to struct
cfg80211_registered_device.
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Name "dev" is too common and ambiguous, let all the pointer name
pointing to struct cfg80211_registered_device be "rdev". This can
improve code readability and consistency(since other places have
already called it rdev).
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The BUG_ON(!err) can't be triggered in the code path, so remove
it.
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

And some code style changes in the function, and correct a typo in
comment.
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Some chips can encrypt managment frames in HW, but
require generated IV in the frame. Add a key flag
that allows us to achieve this.
Signed-off-by: Marek Kwaczynski <marek.kwaczynski@tieto.com>
[use BIT(0) to fill that spot, fix indentation]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

It doesn't make much sense to store refcount in
the chanctx structure. One still needs to hold
chanctx_mtx to get the value safely. Besides,
refcount isn't on performance critical paths.

This will make implementing chanctx reservation
refcounting a little easier.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Channel context refcount is protected by
chanctx_mtx. Accessing the value without holding
the mutex is racy. RCU section didn't guarantee
anything here.

Theoretically ieee80211_channel_switch() could
fail to see refcount change and read "1" instead
of, e.g. "2". This means mac80211 could accept CSA
even though it shouldn't have.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The function did a little too much. Split it up so
the code can be easily reused in the future.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The function did a little too much. Split it up so
the code can be easily reused in the future.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Use a separate function to look for reservation
chanctx. For multi-interface/channel reservation
search sematics differ slightly.

The new routine allows reservations to be merged
with chanctx that are already reserved by other
interface(s).
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This allows new vifs to be assigned to a chanctx
as long as chanctx's reservation chandefs (if any)
and chanctx's current chandef (implied by assigned
vifs at the time, if any) and the new vif chandef
are all compatible.

This implies it is impossible to assign a new vif
to an in-place reservation chanctx.

This gives no advantages for single-channel
hardware. It makes sense for multi-channel
hardware only.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This can be useful. Provides a more straghtforward
way to iterate over interfaces taking part in
chanctx reservation and allows tracking chanctx
usage explicitly.

The structure is protected by local->chanctx_mtx.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This can be useful. Provides a more straghtforward
way to iterate over interfaces bound to a given
chanctx and allows tracking chanctx usage
explicitly.

The structure is protected by local->chanctx_mtx.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Initial chanctx reservation code wasn't aware of
radar detection requirements. This is necessary
for chanctx reservations to be used for channel
switching in the future.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Do not allocate more channel contexts than a
driver is capable for currently matching interface
combination.

This allows the ieee80211_vif_reserve_chanctx() to
act as a guard against breaking interface
combinations.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The utility function has no uses yet. It is aimed
at future chanctx reservation management and
channel switching.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The patch splits cfg80211_check_combinations()
into an iterator function and a simple iteration
user.

This makes it possible for drivers to asses how
many channels can use given iftype setup. This in
turn can be used for future
multi-interface/multi-channel channel switching.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>