In the current minimum chandef code there's an issue in that the
recalculation can happen after rate control is initialized for a
station that has a wider bandwidth than the current chanctx, and
then rate control can immediately start using those higher rates
which could cause problems.
Observe that first of all that this problem is because we don't
take non-associated and non-uploaded stations into account. The
restriction to non-associated is quite pointless and is one of
the causes for the problem described above, since the rate init
will happen before the station is set to associated; no frames
could actually be sent until associated, but the rate table can
already contain higher rates and that might cause problems.
Also, rejecting non-uploaded stations is wrong, since the rate
control can select higher rates for those as well.
Secondly, it's then necessary to recalculate the minimal config
before initializing rate control, so that when rate control is
initialized, the higher rates are already available. This can be
done easily by adding the necessary function call in rate init.
Change-Id: Ib9bc02d34797078db55459d196993f39dcd43070
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Commit 5bcae31d9 (mac80211: implement multi-vif in-place reservations)
introduced ieee80211_vif_use_reserved_switch() with a counter variable
'i' that is set but not used. Compiling with W=1 gives the following
warning, fix it.
net/mac80211/chan.c: In function ‘ieee80211_vif_use_reserved_switch’:
net/mac80211/chan.c:1273:6: warning: variable ‘i’ set but not used [-Wunused-but-set-variable]
This is a harmless warning, and is only being fixed to reduce the
noise obtained with W=1 in the kernel.
Fixes: 5bcae31d9 ("mac80211: implement multi-vif in-place reservations")
Cc: Michal Kazior <michal.kazior@tieto.com>
Cc: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Kirtika Ruchandani <kirtika@chromium.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This code doesn't do much besides allowing to start and
stop the vif.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Ayala Beker <ayala.beker@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This allows user space to start/stop NAN interface.
A NAN interface is like P2P device in a few aspects: it
doesn't have a netdev associated to it.
Add the new interface type and prevent operations that
can't be executed on NAN interface like scan.
Define several attributes that may be configured by user space
when starting NAN functionality (master preference and dual
band operation)
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The min_def chanctx is affected not only by the current chandef, but
sometimes also by other stations on the vif. There's a valid scenario
where a TDLS peer can widen its BW, thereby causing the min_def
to increase.
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>
The minimum chandef bandwidth calculation was done only in case
a new station was inserted (or when an existing station was removed).
However, it is possible that stations are inserted before they are
associated, e.g., when FULL_AP_CLIENT_STATE is supported and user
space adds stations unassociated.
Fix this by calling ieee80211_recalc_min_chandef() whenever
a station transitions in/out the associated state, and only
consider station marked as associated.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Define a station chandef, to be used for wider-bw TDLS peers. When both
peers support the feature, upgrade the channel bandwidth to the maximum
allowed by both peers and regulatory. Currently widths up to 80MHz are
supported in the 5GHz band.
When a TDLS peer connects/disconnects recalculate the channel type of the
current chanctx.
Make the chanctx width calculation consider wider-bw TDLS peers and
similarly fix the max_required_bw calculation for the chanctx min_def.
Since the sta->bandwidth is calculated only later on, take
bss_conf.chandef.width as the minimal width for station interface.
Set the upgraded channel width in the VHT-operation set during TDLS setup.
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>
When a vif starts using a reserved channel context (during CSA, for example)
the required chandef was recalculated, however it was never applied.
This could result in using chanctx with narrower width than actually
required. Fix this by calling ieee80211_change_chanctx with the recalculated
chandef. This both changes the chanctx's width and recalcs min_def.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Reviewed-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In order to speed up mac80211's TX path, add the "fast-xmit" cache
that will cache the data frame 802.11 header and other data to be
able to build the frame more quickly. This cache is rebuilt when
external triggers imply changes, but a lot of the checks done per
packet today are simplified away to the check for the cache.
There's also a more detailed description in the code.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If ieee80211_vif_use_channel() fails, we have to clear
sdata->radar_required (which we might have just set).
Failing to do it results in stale radar_required field
which prevents starting new scan requests.
Reported-by: Jouni Malinen <j@w1.fi>
Signed-off-by: Eliad Peller <eliad@wizery.com>
[use false instead of 0]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Control per packet Transmit Power Control (TPC) in lower drivers
according to TX power settings configured by the user. In particular TPC is
enabled if value passed in enum nl80211_tx_power_setting is
NL80211_TX_POWER_LIMITED (allow using less than specified from userspace),
whereas TPC is disabled if nl80211_tx_power_setting is set to
NL80211_TX_POWER_FIXED (use value configured from userspace)
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
ctx->conf.radar_enabled should reflect whether radar
detection is enabled for the channel context.
When calculating it, make it consider only the vifs
that have this context assigned (instead of all the
vifs).
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
local->radar_detect_enabled should tell whether
radar_detect is enabled on any interface belonging
to local.
However, it's not getting updated correctly
in many cases (actually, when testing with hwsim
it's never been set, even when the dfs master
is beaconing).
Instead of handling all the corner cases
(e.g. channel switch), simply check whether
radar detection is enabled only when needed,
instead of caching the result.
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When the channel switch has been made, a vif is now using
the channel context which was reserved. When that happens,
we need to update the channel context since its parameters
may change.
I hit a case in which I switched to a 40Mhz channel but the
reserved channel context was still on 20Mhz. The rate control
would try to send 40Mhz packets on a 20Mhz channel context and
that made iwlwifi's firmware unhappy.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Instead of keeping track of all those special cases where
VLAN interfaces have no bss_conf.chandef, just make sure
they have the same as the AP interface they belong to.
Among others, this fixes a crash getting a VLAN's channel
from userspace since a NULL channel is returned as a good
result (return value 0) for VLANs since the commit below.
Cc: stable@vger.kernel.org [3.18 only]
Fixes: c12bc4885f ("mac80211: return the vif's chandef in ieee80211_cfg_get_channel()")
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[rewrite commit log]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This patch adds 802.11p OCB (Outside the Context of a BSS) mode
support.
When communicating in OCB mode a mandatory wildcard BSSID
(48 '1' bits) is used.
The EDCA parameters handling function was changed to support
802.11p specific values.
The insertion of a newly discovered STAs is done in the similar way
as in the IBSS mode -- through the deferred insertion.
The OCB mode uses a periodic 'housekeeping task' for expiration of
disconnected STAs (in the similar manner as in the MESH mode).
New Kconfig option for verbose OCB debugging outputs is added.
Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This patch adds new iface type (NL80211_IFTYPE_OCB) representing
the OCB (Outside the Context of a BSS) mode.
When establishing a connection to the network a cfg80211_join_ocb
function is called (particular nl80211_command is added as well).
A mandatory parameters during the ocb_join operation are 'center
frequency' and 'channel width (5/10 MHz)'.
Changes done in mac80211 are minimal possible required to avoid
many warnings (warning: enumeration value 'NL80211_IFTYPE_OCB'
not handled in switch) during compilation. Full functionality
(where needed) is added in the following patch.
Signed-off-by: Rostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Use codespell to find spelling errors.
Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
performance improvements, and various patches all over,
rather than listing them one might as well look into the
git log instead.
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Merge tag 'mac80211-next-for-john-2014-08-29' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Johannes Berg <johannes@sipsolutions.net> says:
"Not that much content this time. Some RCU cleanups, crypto
performance improvements, and various patches all over,
rather than listing them one might as well look into the
git log instead."
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Conflicts:
drivers/net/wireless/ath/wil6210/wmi.c
and adds a terminating NUL-byte to the alpha2 sent to userspace, which
shouldn't be necessary but since many places treat it as a string we
couldn't move to just sending two bytes.
In addition to that, we have two VLAN fixes from Felix, a mesh fix, a
fix for the recently introduced RX aggregation offload, a revert for
a broken patch (that luckily didn't really cause any harm) and a small
fix for alignment in debugfs.
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Merge tag 'mac80211-for-john-2014-08-29' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211
Johannes Berg <johannes@sipsolutions.net> says:
"Here are a few fixes for mac80211. One has been discussed for a while
and adds a terminating NUL-byte to the alpha2 sent to userspace, which
shouldn't be necessary but since many places treat it as a string we
couldn't move to just sending two bytes.
In addition to that, we have two VLAN fixes from Felix, a mesh fix, a
fix for the recently introduced RX aggregation offload, a revert for
a broken patch (that luckily didn't really cause any harm) and a small
fix for alignment in debugfs."
Signed-off-by: John W. Linville <linville@redhat.com>
When a device driver is unloaded local->interfaces
list is cleared. If there was more than 1
interface running and connected (bound to a
chanctx) then chantype recalc was called and it
ended up with compat being NULL causing a call
trace warning.
Warn if compat becomes NULL as a result of
incompatible bss_conf.chandef of interfaces bound
to a given channel context only.
The call trace looked like this:
WARNING: CPU: 2 PID: 2594 at /devel/src/linux/net/mac80211/chan.c:557 ieee80211_recalc_chanctx_chantype+0x2cd/0x2e0()
Modules linked in: ath10k_pci(-) ath10k_core ath
CPU: 2 PID: 2594 Comm: rmmod Tainted: G W 3.16.0-rc1+ #150
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
0000000000000009 ffff88001ea279c0 ffffffff818dfa93 0000000000000000
ffff88001ea279f8 ffffffff810514a8 ffff88001ce09cd0 ffff88001e03cc58
0000000000000000 ffff88001ce08840 ffff88001ce09cd0 ffff88001ea27a08
Call Trace:
[<ffffffff818dfa93>] dump_stack+0x4d/0x66
[<ffffffff810514a8>] warn_slowpath_common+0x78/0xa0
[<ffffffff81051585>] warn_slowpath_null+0x15/0x20
[<ffffffff818a407d>] ieee80211_recalc_chanctx_chantype+0x2cd/0x2e0
[<ffffffff818a3dda>] ? ieee80211_recalc_chanctx_chantype+0x2a/0x2e0
[<ffffffff818a4919>] ieee80211_assign_vif_chanctx+0x1a9/0x770
[<ffffffff818a6220>] __ieee80211_vif_release_channel+0x70/0x130
[<ffffffff818a6dd3>] ieee80211_vif_release_channel+0x43/0xb0
[<ffffffff81885f4e>] ieee80211_stop_ap+0x21e/0x5a0
[<ffffffff8184b9b5>] __cfg80211_stop_ap+0x85/0x520
[<ffffffff8181c188>] __cfg80211_leave+0x68/0x120
[<ffffffff8181c268>] cfg80211_leave+0x28/0x40
[<ffffffff8181c5f3>] cfg80211_netdev_notifier_call+0x373/0x6b0
[<ffffffff8107f965>] notifier_call_chain+0x55/0x110
[<ffffffff8107fa41>] raw_notifier_call_chain+0x11/0x20
[<ffffffff816a8dc0>] call_netdevice_notifiers_info+0x30/0x60
[<ffffffff816a8eb9>] __dev_close_many+0x59/0xf0
[<ffffffff816a9021>] dev_close_many+0x81/0x120
[<ffffffff816aa1c5>] rollback_registered_many+0x115/0x2a0
[<ffffffff816aa3a6>] unregister_netdevice_many+0x16/0xa0
[<ffffffff8187d841>] ieee80211_remove_interfaces+0x121/0x1b0
[<ffffffff8185e0e6>] ieee80211_unregister_hw+0x56/0x110
[<ffffffffa0011ac4>] ath10k_mac_unregister+0x14/0x60 [ath10k_core]
[<ffffffffa0014fe7>] ath10k_core_unregister+0x27/0x40 [ath10k_core]
[<ffffffffa003b1f4>] ath10k_pci_remove+0x44/0xa0 [ath10k_pci]
[<ffffffff81373138>] pci_device_remove+0x28/0x60
[<ffffffff814cb534>] __device_release_driver+0x64/0xd0
[<ffffffff814cbcc8>] driver_detach+0xb8/0xc0
[<ffffffff814cb23a>] bus_remove_driver+0x4a/0xb0
[<ffffffff814cc697>] driver_unregister+0x27/0x50
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When bringing down the AP, a WARN_ON is hit because the bss config chandef
is empty here.
Since AP_VLAN channel settings do not matter for anything chanctx related
(always inherits the settings from the AP interface), let's just ignore
it here.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The new_ctx pointer is set only for non-chanctx drivers. This yielded a
crash for chanctx-based drivers during channel switch finalization:
BUG: unable to handle kernel NULL pointer dereference at 0000000000000020
IP: ieee80211_vif_use_reserved_switch+0x71c/0xb00 [mac80211]
Use an adequate chanctx pointer to fix this.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When lockdep isn't compiled, a local variable isn't used
(it's only in a macro argument), annotate it to suppress
the compiler warning.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Channel switch finalization is now 2-step. First
step is when driver calls chswitch_done(), the
other is when reservation is actually finalized
(which be defered for in-place reservation).
It is now safe to call ieee80211_chswitch_done()
more than once.
Also remove the ieee80211_vif_change_channel()
because it is no longer used.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Channel switch finalization is now 2-step. First
step is when driver calls csa_finish(), the other
is when reservation is actually finalized (which
can be deferred for in-place reservation).
It is now safe to call ieee80211_csa_finish() more
than once.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Multi-vif in-place reservations happen when
it is impossible to allocate more channel contexts
as indicated by interface combinations.
Such reservations are not finalized until all
assigned interfaces are ready.
This still doesn't handle all possible cases
(i.e. degradation of number of channels) 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>
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>
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>
With single-channel drivers, we need to be able to change a running
chanctx if we want to use chanctx reservation. Not all drivers may be
able to do this, so add a flag that indicates support for it.
Changing a running chanctx can also be used as an optimization in
multi-channel drivers when the context needs to be reserved for future
usage.
Introduce IEEE80211_CHANCTX_RESERVED chanctx mode to mark a channel as
reserved so nobody else can use it (since we know it's going to
change). In the future, we may allow several vifs to use the same
reservation as long as they plan to use the chanctx on the same
future channel.
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In order to support channel switch with multiple vifs and multiple
contexts, we implement a concept of channel context reservation. This
allows us to reserve a channel context to be used later.
The reservation functionality is not tied directly to channel switch
and may be used in other situations (eg. reserving a channel context
during IBSS join).
We first check if an existing compatible context exists and if it
does, we reserve it. If there is no compatible context we create a
new one and reserve it.
Additionally, split ieee80211_vif_copy_chanctx_to_vlans() so we can
call it while already holding the chanctx mutex.
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Combine the functions into one, so that we can switch from one context
to the other without having to unassign and assign separately. This
is needed by the channel reservation functionality because otherwise
we have a small period of time when the chanctx is set to NULL, which
can cause problems if someone else is trying to dereference it.
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
ieee80211_vif_change_channel() locks chanctx_mtx. When implementing
channel reservation for CS, we will need to call the function to
change channel when the lock is already held, so split the part that
requires the lock out and leave the locking in the original function.
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
It was impossible to change chanctx of master AP
for AP VLANs because the copy function requires
RTNL which can't be simply taken in mac80211 code
due to possible deadlocks.
This is required for future chanctx reservation
that re-bind vifs to new chanctx. This requires
safe AP VLAN iteration without RTNL.
Now VLANs can be iterated while holding either
RTNL or local->mtx because the list is modified
while holding both of these locks.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Move the counting part of the interface combination check from
cfg80211 to mac80211.
This is needed to simplify locking when the driver has to perform a
combination check by itself (eg. with channel-switch).
Signed-off-by: Luciano Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
rcu_assign_pointer() ensures that the initialization of a structure is
carried out before storing a pointer to that structure. However, in the
case that NULL is assigned there's no structure to initialize so using
RCU_INIT_POINTER instead is safe and more efficient.
Signed-off-by: Monam Agarwal <monamagarwal123@gmail.com>
[squash eight tiny patches, rewrite commit log]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
