As described at [1] some STAs (i.e. Intel 5100 Windows) can end up
correctly BlockAcking incoming frames without delivering them to user
space if a AMPDU subframe got lost and we don't flush the receipients
reorder buffer with a BlockAckReq. This in turn results in stuck
connections.
According to 802.11n-2009 it is not necessary to send a BAR to flush
the recepients RX reorder buffer but we still do that to be polite.
However, assume the following frame exchange:
AP -> STA, AMPDU (failed)
AP -> STA, BAR (failed)
The client in question then ends up in the same situation and won't
deliver frames to userspace anymore since we weren't able to flush
its reorder buffer.
This is not a hypothetical situation but I was able to observe this
exact behavior during a stress test between a rt2800pci AP and a Intel
5100 Windows client.
In order to work around this issue just tear down the BA session as
soon as a BAR failed to be TX'ed.
[1] http://comments.gmane.org/gmane.linux.kernel.wireless.general/66867
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For iwlwifi, I decided not to use this API since
it just increased the complexity for little gain.
Since nobody else intends to use it, let's kill
it again. If anybody later needs to have it, we
can always revive it then.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Add API that allows low level drivers to notify mac80211 about TX
packet loss. This is useful when there are FW triggers to notify the
low level driver about these events.
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
ieee80211_tx_status iterates over all tx rates the driver reports back
in order to
1) mark tx rates as invalid if the driver cannot have tried that rate
2) find the actually used tx rate for the final retransmission
By leaving the for loop when the first invalid rate index is found we
can move the rates_idx assignment after the loop and therefore save
a few assignments and conditionals.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For devices supported by iwlwifi sometimes
off-channel transmissions need to be handled
by the device completely. To support this
mac80211 needs to pass the frame directly
to the driver and not through the TX path
as the driver needs the frame and channel
information at the same time.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
There is a race on sending a data frame before the tx completion
of nullfunc frame for enabling power save. As the data quickly
follows the nullfunc frame, the AP thinks that the station is out
of power save and continues to send the frames. Whereas in the
station, the nullfunc ack will be processed after the tx completion
of data frame and mac80211 goes to powersave. Thus the power
save state mismatch between the station and the AP causes some
data loss and some applications fail because of that. This patch
fixes this issue.
Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When operating in AP mode the wl1271 hardware filters out null-data
packets as well as management packets. This makes it impossible for
mac80211 to monitor the PS mode by using the PM bit of incoming frames.
Implement a HW flag to indicate that mac80211 should ignore the PM bit.
In addition, expose ieee80211_sta_ps_transition() to make low-level
drivers capable of controlling PS-mode.
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When the off-channel TX is done with remain-on-channel
offloaded to hardware, the reported cookie is wrong as
in that case we shouldn't use the SKB as the cookie but
need to instead use the corresponding r-o-c cookie
(XOR'ed with 2 to prevent API mismatches).
Fix this by keeping track of the hw_roc_skb pointer
just for the status processing and use the correct
cookie to report in this case. We can't use the
hw_roc_skb pointer itself because it is NULL'ed when
the frame is transmitted to prevent it being used
twice.
This fixes a bug where the P2P state machine in the
supplicant gets stuck because it never gets a correct
result for its transmitted frame.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
If the nullfunc frame used to probe the AP was not acked, there is no point
in waiting for the probe timeout, so advance to the next try (or disconnect)
immediately.
If we do reach the probe timeout without having received a tx status, the
connection is probably really bad and worth disconnecting.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This implements the new off-channel TX API
in mac80211 with a new work item type. The
operation doesn't add a new work item when
we're on the right channel and there's no
wait time so that for example p2p probe
responses will be transmitted without delay.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
For drivers that have accurate TX status reporting
we can report the number of consecutive lost packets
to userspace using the new cfg80211 CQM event. The
threshold is fixed right now, this may need to be
improved in the future.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
nullfunc frames are better for connection monitoring, because probe requests
are answered even if the AP has already dropped the connection, whereas
nullfunc frames from an unassociated station will trigger a disassoc/deauth
frame from the AP (WLAN_REASON_CLASS3_FRAME_FROM_NONASSOC_STA), which allows
the station to reconnect immediately instead of waiting until it attempts to
transmit the next unicast frame.
This only works on hardware with reliable tx ACK reporting, any other hardware
needs to fall back to the probe request method.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This reverts commit 5ed3bc7288.
It turns-out that not all drivers are calling ieee80211_tx_status from a
compatible context. Revert this for now and try again later...
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Some drivers cannot handle multiple retry rates specified by the rc
algorithm but instead use their own retry table (for example rt2800).
However, if such a device registers itself with a max_rates value of 1
the rc algorithm cannot make use of the extended information the device
can provide about retried rates. On the other hand, if a device
registers itself with a max_rates value > 1 the rc algorithm assumes
that the device can handle multi rate retries.
Fix this issue by introducing another hw parameter max_report_rates that
can be set to a different value then max_rates to indicate if a device
is capable of reporting more rates then specified in max_rates.
Signed-off-by: Helmut Schaa <helmut.schaa@googlemail.com>
Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This patch fixes stale mac80211_tx_control_flags for
filtered / retried frames.
Because ieee80211_handle_filtered_frame feeds skbs back
into the tx path, they have to be stripped of some tx
flags so they won't confuse the stack, driver or device.
Cc: <stable@kernel.org>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Christian Lamparter <chunkeey@googlemail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Standardize logging messages from
printk(KERN_<level> "%s: " fmt , wiphy_name(foo), args);
to
wiphy_<level>(foo, fmt, args);
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Allow userspace to register for more than just
action frames by giving the frame subtype, and
make it possible to use this in various modes
as well.
With some tweaks and some added functionality
this will, in the future, also be usable in AP
mode and be able to replace the cooked monitor
interface currently used in that case.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The sta->last_tx_rate is traditionally updated just before transmitting a
frame based on information from the rate control algorithm. However, for
hardware drivers with IEEE80211_HW_HAS_RATE_CONTROL this is not performed,
as the rate control algorithm is not executed, and because the used rate is
not known before the frame has actually been transmitted.
This causes atleast a fixed 1Mb/s to be reported to user space. A few other
instances of code also rely on this information.
Fix this by setting the sta->last_tx_rate in tx_status handling. There, look
for last rates entry set by the driver, and use that as value for
sta->last_tx_rate.
Signed-off-by: Juuso Oikarinen <juuso.oikarinen@nokia.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When a cooked monitor interface is active, ieee80211_tx_status()
generates a radiotap header for every single frame, even if it wasn't
injected and thus won't be sent to a monitor interface.
This patch reduces cpu utilization by moving the cooked monitor check a
bit earlier, before it generates the rtap header.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This implements a new command to register for action frames
that userspace wants to handle instead of the in-kernel
rejection. It is then responsible for rejecting ones that
it decided not to handle. There is no unregistration, but
the socket can be closed for that.
Frames that are not registered for will not be forwarded
to userspace and will be rejected by the kernel, the
cfg80211 API helps implementing that.
Additionally, this patch adds a new command that allows
doing action frame transmission from userspace. It can be
used either to exchange action frames on the current
operational channel (e.g., with the AP with which we are
currently associated) or to exchange off-channel Public
Action frames with the remain-on-channel command.
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>
Even if the null data frame is not acked by the AP, mac80211
goes into power save. This might lead to loss of frames
from the AP.
Prevent this by restarting dynamic_ps_timer when ack is not
received for null data frames.
Cc: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Vivek Natarajan <vnatarajan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Filtered frames not only need their control information
cleared to avoid wrong checks, but also need to have
jiffies and vif assigned so they can be processed or
expired.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In an earlier commit,
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.
I disabled software retry of failed/filtered frames
because it was broken. With the work of the previous
patches, it now becomes fairly easy to re-enable it
by adding a flag indicating that the frame shouldn't
be modified, but still running it through the transmit
handlers to populate the control information.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When an skb survived a round-trip through the driver
and needs to be re-used, its control information is
definitely not valid any more, the driver will have
overwritten it.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
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>
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>
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>
The station management currently uses the virtual
interface, but you cannot add the same station to
multiple virtual interfaces if you're communicating
with it in multiple ways.
This restriction should be lifted so that in the
future we can, for instance, support bluetooth 3
with an access point that mac80211 is already
associated to.
We can do that by requiring all sta_info_get users
to provide the virtual interface and making the RX
code aware that an address may match more than one
station struct. Thanks to the previous patches this
one isn't all that large and except for the RX and
TX status paths changes has low complexity.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
An earlier optimization on removing unnecessary traffic on cooked
monitor interfaces ("mac80211: reduce the amount of unnecessary traffic
on cooked monitor interfaces ") ended up removing quite a bit more
than just unnecessary traffic. It was not supposed to remove TX status
reporting for injected frames, but ended up doing it by checking the
injected flag in skb->cb only after that field had been cleared with
memset.. Fix this by taking a local copy of the injected flag before
skb->cb is cleared.
This broke user space applications that depend on getting TX status
notifications for injected data frames. For example, STA inactivity
poll from hostapd did not work and ended up kicking out stations even
if they were still present.
Signed-off-by: Jouni Malinen <j@w1.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
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>
