Commit Graph

166 Commits

Author SHA1 Message Date
Johannes Berg 0379185b6c mac80211: annotate station rcu dereferences
The new RCU lockdep support warns about these
in some contexts -- make it aware of the locks
used to protect all this. Different locks are
used in different contexts which unfortunately
means we can't get perfect checking.

Also remove rcu_dereference() from two places
that don't actually dereference the pointers.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-04-06 15:53:30 -04:00
Helmut Schaa b446918b77 mac80211: use listen interval 5 as default
Currently if a driver does not set hw.max_listen_interval a listen
interval of 1 is negotiated with the AP. Thus, the AP could drop
buffered frames for us after just one beacon interval which can
easily happen with the current powersave and scan implementation.
To avoid this issue increase the default interval to 5 which should
be a reasonable safe default.

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-02-26 16:59:11 -05:00
Kalle Valo 50ae0cf15c mac80211: add debugfs interface for U-APSD queue configuration
Because it's not yet decided how to configure which queues are U-APSD
enabled, add a debugfs interface for testing purposes.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-01-12 14:21:00 -05:00
Kalle Valo ab13315af9 mac80211: add U-APSD client support
Add Unscheduled Automatic Power-Save Delivery (U-APSD) client support. The
idea is that the data frames from the client trigger AP to send the buffered
frames with ACs which have U-APSD enabled. This decreases latency and makes it
possible to save even more power.

Driver needs to use IEEE80211_HW_UAPSD to enable the feature. The current
implementation assumes that firmware takes care of the wakeup and
hardware needing IEEE80211_HW_PS_NULLFUNC_STACK is not yet supported.

Tested with wl1251 on a Nokia N900 and Cisco Aironet 1231G AP and running
various test traffic with ping.

Signed-off-by: Kalle Valo <kalle.valo@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-01-12 14:20:58 -05:00
Jouni Malinen 29401f6630 mac80211: No need to include WEXT headers here
Remove the forgotten linux/wireless.h inclusion from mac80211.

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2010-01-05 17:13:13 -05:00
Johannes Berg b8bc4b0aa9 mac80211: support remain-on-channel command
This implements the new remain-on-channel cfg80211
command in mac80211, extending the work interface.

Also change the work purge code to be able to clean
up events properly (pretending they timed out.)

Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-28 16:55:03 -05:00
Johannes Berg 0c1ad2cac1 mac80211: proper bss private data handling
cfg80211 offers private data for each BSS struct,
which mac80211 uses. However, mac80211 uses internal
and external (cfg80211) BSS pointers interchangeably
and has a hack to put the cfg80211 bss struct into
the private struct.

Remove this hack, properly converting between the
pointers wherever necessary.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-28 16:54:59 -05:00
Johannes Berg af6b63741c mac80211: generalise work handling
In order to use auth/assoc for different purposes
other than MLME, it needs to be split up. For other
purposes, a generic work handling (potentially on
another channel) will be useful.

To achieve that, this patch moves much of the MLME
work handling out of mlme into a new work API. The
API can currently handle probing a specific AP,
authentication and association. The MLME previously
handled probe/authentication as one step and will
continue to do so, but they are separate in the new
work handling.

Work items are RCU-managed to be able to check for
existence of an item for a specific frame in the RX
path, but they can be re-used which the MLME right
now will do for its combined probe/auth step.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-28 16:54:55 -05:00
Johannes Berg 9607e6b66a mac80211: add ieee80211_sdata_running
Instead of always using netif_running(sdata->dev)
use ieee80211_sdata_running(sdata) now which is
just an inline containing netif_running() for now.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-28 16:54:49 -05:00
John W. Linville ea1e4b8420 Merge git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-2.6 2009-12-28 15:09:11 -05:00
Johannes Berg f38fd12fa7 mac80211: allow disabling 40MHz on 2.4GHz
In some situations it is required that a system be
configured with no support for 40 MHz channels in
the 2.4 GHz band. Rather than imposing any such
restrictions on everybody, allow configuration a
system like that with a module parameter. It is
writable at runtime but only takes effect at the
time of the next association.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-22 13:31:17 -05:00
Johannes Berg 0f78231bff mac80211: enable spatial multiplexing powersave
Enable spatial multiplexing in mac80211 by telling the
driver what to do and, where necessary, sending action
frames to the AP to update the requested SMPS mode.

Also includes a trivial implementation for hwsim that
just logs the requested mode.

For now, the userspace interface is in debugfs only,
and let you toggle the requested mode at any time.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-22 13:31:16 -05:00
Johannes Berg 12375ef933 mac80211: trace interface name
It's not all that useful to have the vif/sdata pointer,
we'd rather refer to the interfaces by their name.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-21 18:38:54 -05:00
Johannes Berg 47846c9b0c mac80211: reduce reliance on netdev
For bluetooth 3, we will most likely not have
a netdev for a virtual interface (sdata), so
prepare for that by reducing the reliance on
having a netdev. This patch moves the name
and address fields into the sdata struct and
uses them from there all over. Some work is
needed to keep them sync'ed, but that's not
a lot of work and in slow paths anyway.

In doing so, this also reduces the number of
pointer dereferences in many places, because
of things like sdata->dev->dev_addr becoming
sdata->vif.addr.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-21 18:38:52 -05:00
Gertjan van Wingerde d24deb2580 mac80211: Add define for TX headroom reserved by mac80211 itself.
Add a definition of the amount of TX headroom reserved by mac80211 itself
for its own purposes. Also add BUILD_BUG_ON to validate the value.
This define can then be used by drivers to request additional TX headroom
in the most efficient manner.

Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-12-14 14:22:31 -05:00
Joe Perches f64f9e7192 net: Move && and || to end of previous line
Not including net/atm/

Compiled tested x86 allyesconfig only
Added a > 80 column line or two, which I ignored.
Existing checkpatch plaints willfully, cheerfully ignored.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-29 16:55:45 -08:00
Johannes Berg 9bc383de37 cfg80211: introduce capability for 4addr mode
It's very likely that not many devices will support
four-address mode in station or AP mode so introduce
capability bits for both modes, set them in mac80211
and check them when userspace tries to use the mode.
Also, keep track of 4addr in cfg80211 (wireless_dev)
and not in mac80211 any more. mac80211 can also be
improved for the VLAN case by not looking at the
4addr flag but maintaining the station pointer for
it correctly. However, keep track of use_4addr for
station mode in mac80211 to avoid all the derefs.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-19 11:08:53 -05:00
Johannes Berg 5be83de54c cfg80211: convert bools into flags
We've accumulated a number of options for wiphys
which make more sense as flags as we keep adding
more. Convert the existing ones.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-19 11:08:50 -05:00
Johannes Berg fe7a5d5c1a mac80211: move TX status handling
It's enough code to have its own file, I think.
Especially since I'm going to add to it.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-18 17:09:27 -05:00
Johannes Berg c951ad3550 mac80211: convert aggregation to operate on vifs/stas
The entire aggregation code currently operates on the
hw pointer and station addresses, but that needs to
change to make stations purely per-vif; As one step
preparing for that make the aggregation code callable
with the station, or by the combination of virtual
interface and station address.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-18 17:09:15 -05:00
Felix Fietkau 3e5b1101f5 mac80211: reduce the amount of unnecessary traffic on cooked monitor interfaces
In order to handle association and authentication in AP mode,
hostapd needs access to the tx status info of its own frames
through a cooked monitor interface. Without this patch the
cooked monitor interfaces also passed on tx status information
for packets from other virtual interfaces. This creates a
significant performance issue on embedded system. Hostapd
tries to work around this by installing a Linux Socket Filter
that only captures the frames it's interested in, however
data duplication and socket filter matching still uses up
enough CPU cycles to be very noticeable on small systems.
This patch ensures that tx status information of non-injected
frames does not make it to cooked monitor interfaces.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-18 17:09:10 -05:00
Johannes Berg af81858172 mac80211: async station powersave handling
Some devices require that all frames to a station
are flushed when that station goes into powersave
mode before being able to send frames to that
station again when it wakes up or polls -- all in
order to avoid reordering and too many or too few
frames being sent to the station when it polls.

Normally, this is the case unless the station
goes to sleep and wakes up very quickly again.
But in that case, frames for it may be pending
on the hardware queues, and thus races could
happen in the case of multiple hardware queues
used for QoS/WMM. Normally this isn't a problem,
but with the iwlwifi mechanism we need to make
sure the race doesn't happen.

This makes mac80211 able to cope with the race
with driver help by a new WLAN_STA_PS_DRIVER
per-station flag that can be controlled by the
driver and tells mac80211 whether it can transmit
frames or not. This flag must be set according to
very specific rules outlined in the documentation
for the function that controls it.

When we buffer new frames for the station, we
normally set the TIM bit right away, but while
the driver has blocked transmission to that sta
we need to avoid that as well since we cannot
respond to the station if it wakes up due to the
TIM bit. Once the driver unblocks, we can set
the TIM bit.

Similarly, when the station just wakes up, we
need to wait until all other frames are flushed
before we can transmit frames to that station,
so the same applies here, we need to wait for
the driver to give the OK.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-06 16:49:10 -05:00
Johannes Berg c327d96759 mac80211: fix internal scan request
The internal scan request mac80211 uses to
scan for IBSS networks was set up to contain
no channels at all because n_channels wasn't
set after setting up the channels array. Fix
this to properly scan for networks.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-11-04 18:44:52 -05:00
Johannes Berg 7bcfaf2f43 cfg80211/mac80211: use debugfs_remove_recursive
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: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-10-30 16:49:18 -04:00
Johannes Berg ea77f12f2c mac80211: remove tasklet enable/disable
Due to the way the tasklets work in mac80211 there's
no need to ever disable them.

However, we need to clear the pending packets when
taking down the last interface because otherwise
the tx_pending_tasklet might be queued if the
driver mucks with the queues (which it shouldn't).

I've had a situation occasionally with ar9170 in
which ksoftirq was using 100% CPU time because
a disabled tasklet was scheduled, and I think that
was due to ar9170 receiving a packet while the
tasklet was disabled. That's strange and it really
should not do that for other reasons, but there's
no need to waste that much CPU time over it, it
should just warn instead.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-28 14:40:34 -04:00
Johannes Berg 11ba964d4f mac80211: fix register_hw error path
"cfg80211: fix alignment problem in scan request"
introduced a bug into the error path, because now
we allocate the entire scan request and not just
the channel list (the channel list is allocated
together with the scan request) -- on errors we
thus also need to free the entire scan request.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-20 11:36:07 -04:00
Javier Cardona bfc32e6a95 mac80211: Decouple fail_avg stats used by mesh from rate control algorithm.
Mesh uses the tx failure average to compute the (m)path metric.  This used to
be done inside the rate control module.  This patch breaks the dependency
between the mesh stack and the rate control algorithm.  Mesh will now work
independently of the chosen rate control algorithm.

The mesh stack keeps a moving average of the average transmission losses for
each mesh peer station.  If the fail average exceeds a certain threshold, the
peer link is marked as broken.

Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-20 11:36:02 -04:00
Johannes Berg f424afa178 mac80211: remove deprecated API
All but two drivers have now stopped using the two
deprecated members radio_enabled and beacon_int,
so it's about time to remove them for good.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Kalle Valo <kalle.valo@iki.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-20 11:35:58 -04:00
Johannes Berg 3ac64beecd mac80211: allow configure_filter callback to sleep
Over time, a whole bunch of drivers have come up
with their own scheme to delay the configure_filter
operation to a workqueue. To be able to simplify
things, allow configure_filter to sleep, and add
a new prepare_multicast callback that drivers that
need the multicast address list implement. This new
callback must be atomic, but most drivers either
don't care or just calculate a hash which can be
done atomically and then uploaded to the hardware
non-atomically.

A cursory look suggests that at76c50x-usb, ar9170,
mwl8k (which is actually very broken now), rt2x00,
wl1251, wl1271 and zd1211 should make use of this
new capability.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-20 11:35:58 -04:00
Johannes Berg 5ba63533bb cfg80211: fix alignment problem in scan request
The memory layout for scan requests was rather wrong,
we put the scan SSIDs before the channels which could
lead to the channel pointers being unaligned in memory.
It turns out that using a pointer to the channel array
isn't necessary anyway since we can embed a zero-length
array into the struct.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-14 09:13:44 -04:00
Igor Perminov e3b90ca284 mac80211: FIF_PSPOLL filter flag
When an interface is configured in the AP mode, the mac80211
implementation doesn't inform the driver to receive PS Poll frames.
It leads to inability to communicate with power-saving stations
reliably.
The FIF_CONTROL flag isn't passed by mac80211 to
ieee80211_ops.configure_filter when an interface is in the AP mode.
And it's ok, because we don't want to receive ACK frames and other
control ones, but only PS Poll ones.

This patch introduces the FIF_PSPOLL filter flag in addition to
FIF_CONTROL, which means for the driver "pass PS Poll frames".

This flag is passed to the driver:
A) When an interface is configured in the AP mode.
B) In all cases, when the FIF_CONTROL flag was passed earlier (in
addition to it).

Signed-off-by: Igor Perminov <igor.perminov@inbox.ru>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-04 16:44:35 -04:00
Luis R. Rodriguez 42935ecaf4 mac80211: redefine usage of the mac80211 workqueue
The mac80211 workqueue exists to enable mac80211 and drivers
to queue their own work on a single threaded workqueue. mac80211
takes care to flush the workqueue during suspend but we never
really had requirements on drivers for how they should use
the workqueue in consideration for suspend.

We extend mac80211 to document how the mac80211 workqueue should
be used, how it should not be used and finally move raw access to
the workqueue to mac80211 only. Drivers and mac80211 use helpers
to queue work onto the mac80211 workqueue:

  * ieee80211_queue_work()
  * ieee80211_queue_delayed_work()

These helpers will now warn if mac80211 already completed its
suspend cycle and someone is trying to queue work. mac80211
flushes the mac80211 workqueue prior to suspend a few times,
but we haven't taken the care to ensure drivers won't add more
work after suspend. To help with this we add a warning when
someone tries to add work and mac80211 already completed the
suspend cycle.

Drivers should ensure they cancel any work or delayed work
in the mac80211 stop() callback.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-04 16:44:14 -04:00
Bob Copeland 97af743207 mac80211: disable beacons before removing the associated interface
When downing interfaces, it's a good idea to tell the driver to
stop sending beacons; that way the driver doesn't need special
code in ops->remove_interface() when it should already handle the
case in bss_info_changed().

This fixes a potential crash with at least ath5k since the vif
pointer will be nullified while beacon interrupts are still active.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-04 16:43:23 -04:00
Johannes Berg 4da163ab0a mac80211: disable software retry for now
Pavel Roskin reported a problem that seems to be due to
software retry of already transmitted frames. It turns
out that we've never done that correctly, but due to
some recent changes it now crashes in the TX code. I've
added a comment in the patch that explains the problem
better and also points to possible solutions -- which
I can't implement right now.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-04 16:43:18 -04:00
Helmut Schaa fbe9c429f1 mac80211: Replace {sw, hw}_scanning variables with a bitfield
Use a bitfield to store the current scan mode instead of two boolean
variables {sw,hw}_scanning. This patch does not introduce functional
changes but allows us to enhance the scan flags later (for example
for background scanning).

Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-07-27 15:24:16 -04:00
Johannes Berg a272a72066 mac80211: allow using network namespaces
This finally opens up the ability to put mac80211 devices
into different network namespaces. As long as you don't
have sysfs, that is.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-07-27 15:24:08 -04:00
Johannes Berg 3b8d81e020 mac80211: remove master netdev
With the internal 'pending' queue system in place, we can simply
put packets there instead of pushing them off to the master dev,
getting rid of the master interface completely.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-07-24 15:05:30 -04:00
Johannes Berg f1d58c2521 mac80211: push rx status into skb->cb
Within mac80211, we often need to copy the rx status into
skb->cb. This is wasteful, as drivers could be building it
in there to start with. This patch changes the API so that
drivers are expected to pass the RX status in skb->cb, now
accessible as IEEE80211_SKB_RXCB(skb). It also updates all
drivers to pass the rx status in there, but only by making
them memcpy() it into place before the call to the receive
function (ieee80211_rx(_irqsafe)). Each driver can now be
optimised on its own schedule.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-07-10 14:57:54 -04:00
Johannes Berg 8f77f3849c mac80211: do not pass PS frames out of mac80211 again
In order to handle powersave frames properly we had needed
to pass these out to the device queues again, and introduce
the skb->requeue bit. This, however, also has unnecessary
overhead by needing to 'clean up' already tried frames, and
this clean-up code is also buggy when software encryption
is used.

Instead of sending the frames via the master netdev queue
again, simply put them into the pending queue. This also
fixes a problem where frames for that particular station
could be reordered when some were still on the software
queues and older ones are re-injected into the software
queue after them.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-06-10 13:28:37 -04:00
Johannes Berg e535c7566e mac80211: deprecate conf.beacon_int properly
Ivo has updated the driver to no longer use the change flag,
so we can remove that, but rt2x00 and ath5k still use the
actual value so let's mark it as deprecated too.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-06-03 14:05:09 -04:00
Eric Dumazet 1ce8e7b57b net: ALIGN/PTR_ALIGN cleanup in alloc_netdev_mq()/netdev_priv()
Use ALIGN() and PTR_ALIGN() macros instead of handcoding them.

Get rid of NETDEV_ALIGN_CONST ugly define

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-05-27 15:47:06 -07:00
Johannes Berg 9cef873798 mac80211: fix managed mode BSSID handling
Currently, we will ask the driver to configure right away
when somebody changes the desired BSSID. That's totally
strange because then we will configure the driver without
even knowing whether the BSS exists. Change this to only
configure the BSSID when associated, and configure a zero
BSSID when not associated.

As a side effect, this fixes an issue with the iwlwifi
driver which doesn't implement sta_notify properly and
uses the BSSID instead and gets very confused if the
BSSID is cleared before we disassociate, which results
in the warning Marcel posted [1] and iwlwifi bug 1995 [2].

[1] http://thread.gmane.org/gmane.linux.kernel.wireless.general/32598
[2] http://www.intellinuxwireless.org/bugzilla/show_bug.cgi?id=1995

Cc: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-20 14:46:37 -04:00
Johannes Berg 58905ca5b1 mac80211: fix scan channel race
When a software scan starts, it first sets sw_scanning, but
leaves the scan_channel "unset" (it currently actually gets
initialised to a default). Now, when something else tries
to (re)configure the hardware in the window between these two
events (after sw_scanning = true, but before scan_channel is
set), the current code switches to the (unset!) scan_channel.
This causes trouble, especially when switching bands and
sending frames on the wrong channel.

To work around this, leave scan_channel initialised to NULL
and use it to determine whether or not a switch to a different
channel should occur (and also use the same condition to check
whether to adjust power for scan or not).

Additionally, avoid reconfiguring the hardware completely when
recalculating idle resulted in no changes, this was the problem
that originally led us to discover the race condition in the
first place, which was helpfully bisected by Pavel. This part
of the patch should not be necessary with the other fixes, but
not calling the ieee80211_hw_config function when we know it to
be unnecessary is certainly a correct thing to do.

Unfortunately, this patch cannot and does not fix the race
condition completely, but due to the way the scan code is
structured it makes the particular problem Pavel discovered
(race while changing channel at the same time as transmitting
frames) go away. To fix it completely, more work especially
with locking configuration is needed.

Bisected-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-11 15:23:54 -04:00
Johannes Berg 2448798133 mac80211: add driver ops wrappers
In order to later add tracing or verifications to the driver
calls mac80211 makes, this patch adds static inline wrappers
for all operations.

All calls are now written as

	drv_<op>(local, ...);

instead of

	local->ops-><op>(&local->hw, ...);

Where necessary, the wrappers also do existence checking and
return default values as appropriate.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-06 15:14:37 -04:00
Johannes Berg 2d0ddec5b2 mac80211: unify config_interface and bss_info_changed
The config_interface method is a little strange, it contains the
BSSID and beacon updates, while bss_info_changed contains most
other BSS information for each interface. This patch removes
config_interface and rolls all the information it previously
passed to drivers into bss_info_changed.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-06 15:14:36 -04:00
Johannes Berg 57c4d7b4c4 mac80211: clean up beacon interval settings
We currently have two beacon interval configuration knobs:
hw.conf.beacon_int and vif.bss_info.beacon_int. This is
rather confusing, even though the former is used when we
beacon ourselves and the latter when we are associated to
an AP.

This just deprecates the hw.conf.beacon_int setting in favour
of always using vif.bss_info.beacon_int. Since it touches all
the beaconing IBSS code anyway, we can also add support for
the cfg80211 IBSS beacon interval configuration easily.

NOTE: The hw.conf.beacon_int setting is retained for now due
      to drivers still using it -- I couldn't untangle all
      drivers, some are updated in this patch.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-06 15:14:33 -04:00
Johannes Berg f3b85252f0 mac80211: fix scan races and rework scanning
There are some places marked
	/* XXX maybe racy? */
and they really are racy because there's no locking.

This patch reworks much of the scan code, and introduces proper
locking for the scan request as well as the internal scanning
(which is necessary for IBSS/managed modes). Helper functions
are added to call the scanning code whenever necessary. The
scan deferring is changed to simply queue the scanning work
instead of trying to start the scan in place, the scanning work
will then take care of the rest.

Also, currently when internal scans are requested for an interface
that is trying to associate, we reject such scans. This was not
intended, the mlme code has provisions to scan twice when it can't
find the BSS to associate with right away; this has never worked
properly. Fix this by not rejecting internal scan requests for an
interface that is associating.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-06 15:14:31 -04:00
David S. Miller aba7453037 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	Documentation/isdn/00-INDEX
	drivers/net/wireless/iwlwifi/iwl-scan.c
	drivers/net/wireless/rndis_wlan.c
	net/mac80211/main.c
2009-04-29 20:30:35 -07:00
Johannes Berg c428c89201 mac80211: default to automatic power control
In "mac80211: correct wext transmit power handler"
I fixed the wext handler, but forgot to make the default of the
user_power_level -1 (aka "auto"), so that now the transmit power
is always set to 0, causing associations to time out and similar
problems since we're transmitting with very little power. Correct
this by correcting the default user_power_level to -1.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Bisected-by: Niel Lambrechts <niel.lambrechts@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-29 16:48:33 -04:00
Alan Jenkins d4c4a9a1bc mac80211: fix modprobe deadlock by not calling wep_init under rtnl_lock
- ieee80211_wep_init(), which is called with rtnl_lock held, blocks in
   request_module() [waiting for modprobe to load a crypto module].

 - modprobe blocks in a call to flush_workqueue(), when it closes a TTY
   [presumably when it exits].

 - The workqueue item linkwatch_event() blocks on rtnl_lock.

There's no reason for wep_init() to be called with rtnl_lock held, so
just move it outside the critical section.

Signed-off-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-04-29 16:48:33 -04:00