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>

This patch removes wme_tx_queue and wme_rx_queue from struct sta_info
and from the debugfs sub-structure of struct sta_info
in net/mac80211/sta_info.h, as they are useless and not used.
Signed-off-by: NRami Rosen <ramirose@gmail.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Long awaited, hard work. This patch totally cleans up the rate control
API to remove the requirement to include internal headers outside of
net/mac80211/.

There's one internal use in the PID algorithm left for mesh networking,
we'll have to figure out a way to clean that one up and decide how to
do the peer link evaluation, possibly independent of the rate control
algorithm or via new API.

Additionally, ath9k is left using the cross-inclusion hack for now, we
will add new API where necessary to make this work properly, but right
now I'm not expert enough to do it. It's still off better than before.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Sorry, forgot to run kernel-doc and just got the output from the nightly
run by email, this fixes a warning which I introduced when doing the
first RC API cleanups.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Rate control algorithms may need access to a station's
HT capabilities, so share the ht_info struct in the
public station API.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The sta_info->txrate_idx member isn't used by all RC algorithms
in the way it was intended to be used, move it into those that
require it (only PID) and keep track in the core code of which
rate was last used for reporting to userspace and the mesh MLME.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

As more preparation for a saner rate control algorithm API,
share the supported rates bitmap in the public API.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This variable in sta_info is only used in a meaningful way
by the Intel RC algorithms, so move it into those.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch fixes mac80211 to not rely on the rate control
algorithm to update sta->tx_retry_failed and sta->tx_retry_count
(even if we don't currently use them), removes a number of
completely unused values we don't even show in debugfs and
changes the code in ieee80211_tx_status() to not look up the
sta_info repeatedly.

The only behaviour change here would be not calling the rate
control function rate_control_tx_status() when no sta_info is
found, but all rate control algorithms ignore such calls anyway.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch changes mac80211 to share some more data about
stations with drivers. Should help iwlwifi and ath9k when
 they get around to updating, and might also help with
implementing rate control algorithms without internals.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

ieee80211_sta_expire uses the internal __sta_info_unlink
function which can become static if this function is moved
to sta_info.c.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fix mac80211 kernel-doc missing struct field:

Warning(linux-2.6.27-rc1-git2//net/mac80211/sta_info.h:329): No description found for parameter 'tid_seq[IEEE80211_QOS_CTL_TID_MASK + 1]'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch makes mac80211 assign proper sequence numbers to
QoS-data frames. It also removes the old sequence number code
because we noticed that only the driver or hardware can assign
sequence numbers to non-QoS-data and especially management
frames in a race-free manner because beacons aren't passed
through mac80211's TX path.

This patch also adds temporary code to the rt2x00 drivers to
not break them completely, that code will have to be reworked
for proper sequence numbers on beacons.

It also moves sequence number assignment down in the TX path
so no sequence numbers are assigned to frames that are dropped.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Fix more than 50 kernel-doc warnings in ieee80211/mac80211 kernel-doc notation.
Fix a few typos also.

Note: Some fields are marked as TBD and need to have their description
corrected.
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

David Ellingsworth posted a bug that was only noticable on UP/NO-PREEMPT
and Michael correctly analysed it to be a spin_lock_bh() section within
a spin_lock_irqsave() section. This adds a separate spinlock for the
sta_info flags to fix that issue and avoid having to take much care
about where the sta flag manipulation functions are called.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Reported-By: NDavid Ellingsworth <david@identd.dyndns.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The useless channel use statistics are quite a lot of code, currently
use integer divisions in the packet fast path, are rather inaccurate
since they do not account for retries and finally nobody even cares.
Hence, remove them completely.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch converts mac80211 and all drivers to have transmit
information and status in skb->cb rather than allocating extra
memory for it and copying all the data around. To make it fit,
a union is used where only data that is necessary for all steps
is kept outside of the union.

A number of fixes were done by Ivo, as well as the rt2x00 part
of this patch.
Signed-off-by: NIvo van Doorn <IvDoorn@gmail.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Acked-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

trying to clean up the signal/noise code. the previous code in mac80211 had
confusing names for the related variables, did not have much definition of
what units of signal and noise were provided and used implicit mechanisms from
the wireless extensions.

this patch introduces hardware capability flags to let the hardware specify
clearly if it can provide signal and noise level values and which units it can
provide. this also anticipates possible new units like RCPI in the future.

for signal:

  IEEE80211_HW_SIGNAL_UNSPEC - unspecified, unknown, hw specific
  IEEE80211_HW_SIGNAL_DB     - dB difference to unspecified reference point
  IEEE80211_HW_SIGNAL_DBM    - dBm, difference to 1mW

for noise we currently only have dBm:

  IEEE80211_HW_NOISE_DBM     - dBm, difference to 1mW

if IEEE80211_HW_SIGNAL_UNSPEC or IEEE80211_HW_SIGNAL_DB is used the driver has
to provide the maximum value (max_signal) it reports in order for applications
to make sense of the signal values.

i tried my best to find out for each driver what it can provide and update it
but i'm not sure (?) for some of them and used the more conservative guess in
doubt. this can be fixed easily after this patch has been merged by changing
the hardware flags of the driver.

DRIVER          SIGNAL    MAX	NOISE   QUAL
-----------------------------------------------------------------
adm8211         unspec(?) 100   n/a     missing
at76_usb        unspec(?) (?)   unused  missing
ath5k           dBm             dBm     percent rssi
b43legacy       dBm             dBm     percent jssi(?)
b43             dBm             dBm     percent jssi(?)
iwl-3945        dBm             dBm     percent snr+more
iwl-4965        dBm             dBm     percent snr+more
p54             unspec    127   n/a     missing
rt2x00          dBm	        n/a     percent rssi+tx/rx frame success
  rt2400        dBm             n/a
  rt2500pci     dBm             n/a
  rt2500usb     dBm             n/a
  rt61pci       dBm             n/a
  rt73usb       dBm             n/a
rtl8180         unspec(?) 65    n/a     (?)
rtl8187         unspec(?) 65    (?)     noise(?)
zd1211          dB(?)     100   n/a     percent

drivers/net/wireless/ath5k/base.c:      Changes-licensed-under: 3-Clause-BSD
Signed-off-by: NBruno Randolf <br1@einfach.org>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

As discussed earlier, we can unify locking in struct sta_info
and use just a single spinlock protecting all members of the
structure that need protection. Many don't, but one of the
especially bad ones is the 'flags' member that can currently
be clobbered when RX and TX is being processed on different
CPUs at the same time.

Because having four spinlocks for different, mostly exclusive
parts of a single structure is overkill, this patch also kills
the ampdu and mesh plink spinlocks and uses just a single one
for everything. Because none of the spinlocks are nested, this
is safe.

It remains to be seen whether or not we should make the sta
flags use atomic bit operations instead, for now though this
is a safe thing and using atomic operations instead will be
very simple using the new static inline functions this patch
introduces for accessing sta->flags.

Since spin_lock_bh() is used with this lock, there shouldn't
be any contention even if aggregation is enabled at around the
same time as both requires frame transmission/reception which
is in a bh context.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: Tomas Winkler <tomasw@gmail.com>
Cc: Ron Rindjunsky <ron.rindjunsky@intel.com>
Cc: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch renames all mac80211 files (except ieee80211_i.h) to get rid
of the useless ieee80211_ prefix.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Up to now, key manipulation is supposed to run under RTNL to
avoid concurrent manipulations and also allow the set_key()
hardware callback to sleep. This is not feasible because STA
structs are rcu-protected and thus a lot of operations there
cannot take the RTNL. Also, key references are rcu-protected
so we cannot do things atomically.

This patch changes key locking completely:
 * key operations are now atomic
 * hardware crypto offload is enabled and disabled from
   a workqueue, due to that key freeing is also delayed
 * debugfs code is also run from a workqueue
 * keys reference STAs (and vice versa!) so during STA
   unlink the STAs key reference is removed but not the
   keys STA reference, to avoid races key todo work is
   run before STA destruction.
 * fewer STA operations now need the RTNL which was
   required due to key operations

This fixes the locking problems lockdep pointed out and also
makes things more light-weight because the rtnl isn't required
as much.

Note that the key todo lock/key mutex are global locks, this
is not required, of course, they could be per-hardware instead.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NLuis Carlos Cobo <luisca@cozybit.com>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When the IBSS code tries to flush the STA list, it does so in
an atomic context. Flushing isn't safe there, however, and
requires the RTNL, so we need to defer it to a workqueue.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch reorders some fields in various structures to have
less padding within the structures, making them smaller. It
doesn't yet make any type adjustments, but often size_t is used
for example for IE lengths which is total overkill since size_t
will be 8 bytes long on 64-bit yet the length can at most fill
a u8.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch alters the A-MPDU MLME in sta_info to use dynamic allocation,
thus drastically improving memory usage - from a constant ~2 Kbyte in
the previous (static) allocation to a lower limit of ~200 Byte and an upper
limit of ~2 Kbyte.
Signed-off-by: NRon Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch eliminate the use of buf_size as a trigger in favor of a new
flag to control Rx A-MPDU sessions through debugfs
Signed-off-by: NRon Rindjunsky <ron.rindjunsky@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Signed-off-by: NLuis Carlos Cobo <luisca@cozybit.com>
Acked-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When we take down an interface, we need to remove the STA info
items that belong to it because otherwise we might invoke a
sta_notify() callback in the driver when we later delete the
STA entries, but in that case the driver will already have
removed its knowledge of the interface they belonged to leading
to confusion. Also, we could invoke the set_tim() callback after
the driver removed its knowledge of the interface, which can
lead to a crash if it requests a beacon with a then-invalid vif
pointer!

A side effect of this patch is that, because it was easier, it
disallows changing the WDS peer while an interface is up. Should
that actually be necessary, it can be added back, but the WDS
peer STA entry may not be added while the interface is UP so for
now I've simplified the WDS peer's STA entry lifetime management.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This patch cleans up the sta_info struct and documents how
each set of variables is locked. Notably, flags locking is
completely missing. It also adds kernel-doc for some (but
not all yet) members of the struct.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

sta_info_add() has two functions: allocating a station info
structure and inserting it into the hash table/list. Splitting
these two functions allows allocating with GFP_KERNEL in many
places instead of GFP_ATOMIC which is now required by the RCU
protection. Additionally, in many places RCU protection is now
no longer needed at all because between sta_info_alloc() and
sta_info_insert() the caller owns the structure.

This fixes a few race conditions with setting initial flags
and similar, but not all (see comments in ieee80211_sta.c and
cfg.c). More documentation on the existing races will be in
a follow-up patch.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This makes access to the STA hash table/list use RCU to protect
against freeing of items. However, it's not a true RCU, the
copy step is missing: whenever somebody changes a STA item it
is simply updated. This is an existing race condition that is
now somewhat understandable.

This patch also fixes the race key freeing vs. STA destruction
by making sure that sta_info_destroy() is always called under
RTNL and frees the key.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Three __le16s followed by an enum (int) leave a two-byte hole
of padding which we can use for two of the other fields.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Moves another ifdef into the sta_info header file in favour of
compiling more code even w/o CONFIG_MAC80211_MESH.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Various cleanups, reducing the #ifdef mess and other things.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

Includes integration in struct sta_info of mesh peer link elements, previously
on their own mesh peer link table.
Signed-off-by: NLuis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

These things aren't used and the only possible use is within
rate control algorithms, however those can, if they need it,
keep track of it in their private data. last_ack_ms isn't
even updated so completely useless.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

When a STA structure is added, it is often checked whether it
already exists before adding it. This, however, isn't done
atomically so there is a race condition that could lead to two
STA structures being added with the same MAC address. This
patch changes sta_info_add() to return an ERR_PTR in case
of failure and adds the failure mode -EEXIST when the STA
already exists.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Cc: Luis Carlos Cobo <luisca@cozybit.com>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This reworks the code for TX filtered frames, splitting it out to
a new function to handle those cases, making the clear instruction
a flag and renaming a few things to be easier to understand and
less Atheros hardware specific. Finally, it also makes the comments
explain more.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

This consolidates all TIM handling code to avoid re-introducing
errors with the bitmap/set_tim order and to reduce code. While
reading the code I noticed a possible problem so I also added
a comment about that.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>

The TIM flag that is kept in each station's info is completely
useless, there's no code (aside from the debugfs display code)
checking it, hence it can be removed. While doing that, I noticed
that the TIM handling is broken when buffered frames expire, so
fix that.
Signed-off-by: NJohannes Berg <johannes@sipsolutions.net>
Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>