Since we want the code to be able to sleep
in the future, it must not be called from
the timer directly. To prepare, move it out
into the aggregation work.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the driver or rate control requests starting
or stopping an aggregation session, that currently
causes a direct callback into the driver, which
could potentially cause locking problems. Also,
the functions need to be callable from contexts
that cannot sleep, and thus will interfere with
making the ampdu_action callback sleeping.

To address these issues, add a new work item for
each station that will process any start or stop
requests out of line.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Currently we allocate some memory for each TX
aggregation session and additionally keep a
state bitmap indicating the state it is in.
By using RCU to protect the pointer, moving
the state into the structure and some locking
trickery we can avoid locking when the TX agg
session is fully operational.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Currently we allocate some memory for each RX
aggregation session and additionally keep a
flag indicating whether or not it is valid.
By using RCU to protect the pointer and making
sure that the memory is fully set up before it
becomes visible to the RX path, we can remove
the need for the bool that indicates validity,
as well as for locking on the RX path since it
is always synchronised against itself, and we
can guarantee that all other modifications are
done when the structure is not visible to the
RX path.

The net result is that since we remove locking
requirements from the RX path, we can in the
future use any kind of lock for the setup and
teardown code paths.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

A number of places use RCU locking for accessing
the station list, even though they do not need
to. Use mutex locking instead to prepare for the
locking changes I want to make. The mlme code is
also using a WLAN_STA_DISASSOC flag that has the
same meaning as WLAN_STA_BLOCK_BA, so use that.

While doing so, combine places where we loop
over stations twice, and optimise away some of
the loops by checking if the hardware supports
aggregation at all first.

Also fix a more theoretical race condition: right
now we could resume, set up an aggregation session,
and right after tear it down again due to the code
that is needed for hardware reconfiguration here.
Also mark add a comment to that code marking it as
a workaround.

Finally, remove a pointless aggregation disabling
loop when an interface is stopped, directly after
that we remove all stations from it which will also
disable all aggregation sessions that may still be
active, and does so in a race-free way unlike the
current loop that doesn't block new sessions.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

For some odd reason, the plink_state enum is
declared in the middle between aggregation
related structures. Move it down to make the
file easier to read.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fix sta_info.h kernel-doc warnings:

Warning(net/mac80211/sta_info.h:164): No description found for parameter 'tid_active_rx[STA_TID_NUM]'
Warning(net/mac80211/sta_info.h:164): Excess struct/union/enum/typedef member 'tid_state_rx' description in 'sta_ampdu_mlme'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The aggregation code has a number of quirks, like
inventing an unneeded WLAN_BACK_TIMER value and
leaking memory under certain circumstances during
station destruction. Fix these issues by using
the regular aggregation session teardown code and
blocking new aggregation sessions, all before the
station is really destructed.

As a side effect, this gets rid of the long code
block to destroy aggregation safely.

Additionally, rename tid_state_rx which can only
have the values IDLE and OPERATIONAL to
tid_active_rx to make it easier to understand
that there is no bitwise stuff going on on the
RX side -- the TX side remains because it needs
to keep track of the driver and peer states.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

I want to use it during station destruction as well
so rename it to WLAN_STA_BLOCK_BA which is also the
only use of it now.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The noise value as is won't be used, isn't
filled by most drivers and doesn't really
make a whole lot of sense on a per packet
basis -- proper cfg80211 survey support in
mac80211 will need to be different.

Mark the struct member as deprecated so it
will be removed from drivers.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

In associated state, when bringing an interface down, existing
BA sessions are torn down. When this is in progress, nothing
prevents mac80211 from accepting another BA session start request.

Use a new station flag to fix this.
Signed-off-by: NSujith <Sujith.Manoharan@atheros.com>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Many drivers would like to sleep during station
addition and removal, and currently have a high
complexity there from not being able to.

This introduces two new callbacks sta_add() and
sta_remove() that drivers can implement instead
of using sta_notify() and that can sleep, and
the new sta_add() callback is also allowed to
fail.

The reason we didn't do this previously is that
the IBSS code wants to insert stations from the
RX path, which is a tasklet, so cannot sleep.
This patch will keep the station allocation in
that path, but moves adding the station to the
driver out of line. Since the addition can now
fail, we can have IBSS peer structs the driver
rejected -- in that case we still talk to the
station but never tell the driver about it in
the control.sta pointer. If there will ever be
a driver that has a low limit on the number of
stations and that cannot talk to any stations
that are not known to it, we need to do come up
with a new strategy of handling larger IBSSs,
maybe quicker expiry or rejecting peers.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Since the per-vif station changes, sta_info_get on the ap sdata no
longer returns entries for stations on ap vlans. This causes issues
with hostapd, which currently always passes the ap interface name to
nl80211 calls. This patch provides bug compatibility with the earlier
versions until hostapd is fixed.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohn 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: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fix the following htmldocs warnings:

  Warning(net/mac80211/sta_info.h:322): No description found for parameter 'drv_unblock_wk'
  Warning(net/mac80211/sta_info.h:322): No description found for parameter 'drv_unblock_wk'
Signed-off-by: NJaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John W. Linville <linville@tuxdriver.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Cc: David Miller <davem@davemloft.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Instead of filtering by device, directly look up by sdata.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This value is unused by mac80211, because it was only
be used by wireless extensions, and turned out to not
be useful there because the quality value needs to be
comparable between scan results and the current value
which is impossible when the qual value is calculated
taking into account noise, for example.

Since it is unused anyway, this patch deprecates it
in the hope that drivers will remove their sometimes
quite expensive calculations of the value.

I'm open to actual uses of the value, but the best
way of using it seems to be what the Intel drivers do
which should probably be generalised if we have noise
values from the hardware.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

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: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When a station queries us for a PS-poll response, we wrongly
queue the frame on the virtual interface's queue rather than
the pending queue.

Additionally, fix a race condition where we could potentially
send multiple frames to the sleeping station due to using a
station flag rather than a packet flag. When converting to a
packet flag, we can also convert p54 and remove the filter
clearing we added for it.

(Also remove a now dead function)
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Reported-by: NBob Copeland <me@bobcopeland.com>
Tested-by: NBob Copeland <me@bobcopeland.com>
Cc: Christian Lamparter <chunkeey@web.de>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We had code for a number of files, that we didn't publish
in debugfs, fix that. Also make the agg_status file layout
more readable and add more information to it.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Moving information from config_interface to bss_info_changed
removed struct ieee80211_if_conf which the documentation still
refers to, additionally there's one kernel-doc description too
much and one other missing, fix all this.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

We forgot to cancel all timers in mac80211 when suspending.
In particular we forgot to deal with some things that can
cause hardware reconfiguration -- while it is down.

While at it we go ahead and add a warning in ieee80211_sta_work()
if its run while the suspend->resume cycle is in effect. This
should not happen and if it does it would indicate there is
a bug lurking in either mac80211 or mac80211 drivers.

With this now wpa_supplicant doesn't blink when I go to suspend
and resume where as before there where issues with some timers
running during the suspend->resume cycle. This caused a lot of
incorrect assumptions and would at times bring back the device
in an incoherent, but mostly recoverable, state.
Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch allows skbs to be released from the RX reorder buffer in
case they have been there for an unexpectedly long time without us
having received the missing frames before them. Previously, these
frames were only released when the reorder window moved and that could
take very long time unless new frames were received constantly (e.g.,
TCP connections could be killed more or less indefinitely).

This situation should not happen very frequently, but it looks like
there are some scenarious that trigger it for some reason. As such,
this should be considered mostly a workaround to speed up recovery
from unexpected siutation that could result in connections hanging for
long periods of time.

The changes here will only check for timeout situation when adding new
RX frames to the reorder buffer. It does not handle all possible
cases, but seems to help for most cases that could result from common
network usage (e.g., TCP retrying at least couple of times). For more
completely coverage, a timer could be used to periodically check
whether there are any frames remaining in the reorder buffer if no new
frames are received.
Signed-off-by: NJouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This converts mac80211 to the new cfg80211 IBSS API, the
wext handling functions are called where appropriate.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch removes all the virtual A-MPDU-queue bookkeeping from
mac80211. Curiously, iwlwifi already does its own bookkeeping, so
it doesn't require much changes except where it needs to handle
starting and stopping the queues in mac80211.

To handle the queue stop/wake properly, we rewrite the software
queue number for aggregation frames and internally to iwlwifi keep
track of the queues that map into the same AC queue, and only talk
to mac80211 about the AC queue. The implementation requires calling
two new functions, iwl_stop_queue and iwl_wake_queue instead of the
mac80211 counterparts.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: Reinette Chattre <reinette.chatre@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Instead of stopping the entire AC queue when enabling aggregation
(which was only done for hardware with aggregation queues) buffer
the packets for each station, and release them to the pending skb
queue once aggregation is turned on successfully.

We get a little more code, but it becomes conceptually simpler and
we can remove the entire virtual queue mechanism from mac80211 in
a follow-up patch.

This changes how mac80211 behaves towards drivers that support
aggregation but have no hardware queues -- those drivers will now
not be handed packets while the aggregation session is being
established, but only after it has been fully established.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the driver has been notified with a STA_REMOVE, it tears down
the internal ADDBA state. On resume, trying to initiate aggregation would
fail because mac80211 has not cleared the operational state for that <TID,STA>.
This can be fixed by tearing down the existing sessions on a suspend.

Also, the driver can initiate a new BA session when suspend is in progress.
This is fixed by marking the station as being in suspend state and
denying ADDBA requests for such STAs.
Signed-off-by: NSujith <Sujith.Manoharan@atheros.com>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Document the new shutdown member.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Hardware with AMPDU queues currently has broken aggregation.

This patch fixes it by making all A-MPDUs go over the regular AC queues,
but keeping track of the hardware queues in mac80211. As a first rough
version, it actually stops the AC queue for extended periods of time,
which can be removed by adding buffering internal to mac80211, but is
currently not a huge problem because people rarely use multiple TIDs
that are in the same AC (and iwlwifi currently doesn't operate as AP).

This is a short-term fix, my current medium-term plan, which I hope to
execute soon as well, but am not sure can finish before .30, looks like
this:
 1) rework the internal queuing layer in mac80211 that we use for
    fragments if the driver stopped queue in the middle of a fragmented
    frame to be able to queue more frames at once (rather than just a
    single frame with its fragments)
 2) instead of stopping the entire AC queue, queue up the frames in a
    per-station/per-TID queue during aggregation session initiation,
    when the session has come up take all those frames and put them
    onto the queue from 1)
 3) push the ampdu queue layer abstraction this patch introduces in
    mac80211 into the driver, and remove the virtual queue stuff from
    mac80211 again

This plan will probably also affect ath9k in that mac80211 queues the
frames instead of passing them down, even when there are no ampdu queues.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

As far as I can tell, there are possible lockups because both the RX
session_timer and TX addba_resp_timer are del_timer_sync'ed under
the sta spinlock which both timer functions take. Additionally, the
TX agg code seems to leak memory when TX aggregation is not disabled
before the sta_info is freed.

Fix this by making the free code a little smarter in the RX agg case,
and actually make the sta_info_destroy code free the TX agg info in
the TX agg case. We won't notify the peer, but it'll notice something
is wrong anyway, and normally this only happens after we've told it
in some other way we will no longer talk to it.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The values are in TUs (1.024ms), not ms.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Add flags for setting STA entries and struct ieee80211_if_sta to
indicate whether management frame protection (MFP) is used.
Signed-off-by: NJouni Malinen <j@w1.fi>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch removes an unused definition of MAX_STA_COUNT in sta_info.h.
Signed-off-by: NRami Rosen <ramirose@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fix (delete) more mac80211 kernel-doc:

Warning(linux-2.6.28-git13//include/net/mac80211.h:375): Excess struct/union/enum/typedef member 'retry_count' description in 'ieee80211_tx_info'
Warning(linux-2.6.28-git13//net/mac80211/sta_info.h:308): Excess struct/union/enum/typedef member 'last_txrate' description in 'sta_info'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Delete kernel-doc struct descriptions for fields that don't exist:

Warning(include/net/mac80211.h:1263): Excess struct/union/enum/typedef member 'conf_ht' description in 'ieee80211_ops'
Warning(net/mac80211/sta_info.h:309): Excess struct/union/enum/typedef member 'addr' description in 'sta_info'
Warning(net/mac80211/sta_info.h:309): Excess struct/union/enum/typedef member 'aid' description in 'sta_info'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
cc: Johannes Berg <johannes@sipsolutions.net>
cc: John W. Linville <linville@tuxdriver.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

One parameter wasn't described and one I forgot to update when
renaming it; also update TBDs in sta_info.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

So after the previous changes we were still unhappy with how
convoluted the API is and decided to make things simpler for
everybody. This completely changes the rate control API, now
taking into account 802.11n with MCS rates and more control,
most drivers don't support that though.
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When debugfs_create_dir fails, sta_info_debugfs_add_work will not
terminate because it will find the same station again and again.
This is possible whenever debugfs fails for whatever reason; one
reason is a race condition in mac80211, unfortunately we cannot
do much about it, so just document it, it just means some station
may be missing from debugfs.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: Robin Holt <holt@sgi.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>