The regular RX path has a lot of code, but with a few
assumptions on the hardware it's possible to reduce the
amount of code significantly. Currently the assumptions
on the driver are the following:
 * hardware/driver reordering buffer (if supporting aggregation)
 * hardware/driver decryption & PN checking (if using encryption)
 * hardware/driver did de-duplication
 * hardware/driver did A-MSDU deaggregation
 * AP_LINK_PS is used (in AP mode)
 * no client powersave handling in mac80211 (in client mode)

of which some are actually checked per packet:
 * de-duplication
 * PN checking
 * decryption
and additionally packets must
 * not be A-MSDU (have been deaggregated by driver/device)
 * be data packets
 * not be fragmented
 * be unicast
 * have RFC 1042 header

Additionally dynamically we assume:
 * no encryption or CCMP/GCMP, TKIP/WEP/other not allowed
 * station must be authorized
 * 4-addr format not enabled

Some data needed for the RX path is cached in a new per-station
"fast_rx" structure, so that we only need to look at this and
the packet, no other memory when processing packets on the fast
RX path.

After doing the above per-packet checks, the data path collapses
down to a pretty simple conversion function taking advantage of
the data cached in the small fast_rx struct.

This should speed up the RX processing, and will make it easier
to reason about parallelizing RX (for which statistics will need
to be per-CPU still.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

On 32-bit platforms, the 64-bit counters we keep need to be protected
to be consistently read. Use the u64_stats_sync mechanism to do that.

In order to not end up with overly long lines, refactor the tidstats
assignments a bit.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When storing the last_rate_* values in the RX code, there's nothing
to guarantee consistency, so a concurrent reader could see, e.g.
last_rate_idx on the new value, but last_rate_flag still on the old,
getting completely bogus values in the end.

To fix this, I lifted the sta_stats_encode_rate() function from my
old rate statistics code, which encodes the entire rate data into a
single 16-bit value, avoiding the consistency issue.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Move the averaged values out of rx_stats and into rx_stats_avg,
to cleanly split them out. The averaged ones cannot be supported
for parallel RX in a per-CPU fashion, while the other values can
be collected per CPU and then combined/selected when needed.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Move the semicolon, people typically assume that and
once line already put a semicolon behind the "call".
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

For the RX MSDU statistics, we need to count the number of
MSDUs created and accepted from an A-MSDU. Right now, all
frames in any A-MSDUs were completely ignored. Fix this by
moving the RX MSDU statistics accounting into the deliver
function.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Sometimes drivers already looked up, or know out-of-band
from their device, which station transmitted a given RX
frame. Allow them to pass the station pointer to mac80211
to save the extra lookup.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The code is only used with iwlwifi, but still should have proper
mac80211 naming scheme; fix that.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If the device implements dynamic PS itself, there's no need
to ever start the dynamic powersave timer on RX.

While at it, fix up some indentation in this code.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since offset is zero, it's not necessary to use set function. Reset
function is straightforward, and will remove the unnecessary add
operation in set function.
Signed-off-by: NZhang Shengju <zhangshengju@cmss.chinamobile.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Public Action frames use special rules for how the BSSID field (Address
3) is set. A wildcard BSSID is used in cases where the transmitter and
recipient are not members of the same BSS. As such, we need to accept
Public Action frames with wildcard BSSID.

Commit db8e1732 ("mac80211: ignore frames between TDLS peers when
operating as AP") added a rule that drops Action frames to TDLS-peers
based on an Action frame having different DA (Address 1) and BSSID
(Address 3) values. This is not correct since it misses the possibility
of BSSID being a wildcard BSSID in which case the Address 1 would not
necessarily match.

Fix this by allowing mac80211 to accept wildcard BSSID in an Action
frame when in AP mode.

Fixes: db8e1732 ("mac80211: ignore frames between TDLS peers when operating as AP")
Cc: stable@vger.kernel.org
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Just like for CCMP we need to check that for GCMP the fragments
have PNs that increment by one; the spec was updated to fix this
security issue and now has the following text:

	The receiver shall discard MSDUs and MMPDUs whose constituent
	MPDU PN values are not incrementing in steps of 1.

Adapt the code for CCMP to work for GCMP as well, luckily the
relevant fields already alias each other so no code duplication
is needed (just check the aliasing with BUILD_BUG_ON.)

Cc: stable@vger.kernel.org
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Remember the last time when a mpp table entry is used for
rx or tx and remove them after MESH_PATH_EXPIRE time.
Acked-by: NBob Copeland <me@bobcopeland.com>
Signed-off-by: NHenning Rogge <henning.rogge@fkie.fraunhofer.de>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Prepararation for zero-copy A-MSDU support with page fragment SKBs
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If any frames are dropped that are part of a BA session, the reorder
buffer will "indefinitely" (until the timeout) wait for them to come
in (or a BAR moving the window) and won't release frames after them.
This means it isn't possible to filter frames within a BA session in
firmware.

Introduce an API function that allows such filtering. Calling this
function will move the BA window forward to the new SSN, and allows
marking frames after the SSN as having been filtered, so any future
reordering activity will release frames while skipping the holes.
Signed-off-by: NSara Sharon <sara.sharon@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Clean up ieee80211_rx_reorder_ready() callers by passing the RX
TID struct and the index, instead of the frames list. This will
make it more extensible as well.

While at it, move the inline to rx.c as it's only used there.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The ieee80211_queue_stopped() expects hw queue
number but it was given raw WMM AC number instead.

This could cause frame drops and problems with
traffic in some cases - most notably if driver
doesn't map AC numbers to queue numbers 1:1 and
uses ieee80211_stop_queues() and
ieee80211_wake_queue() only without ever calling
ieee80211_wake_queues().

On ath10k it was possible to hit this problem in
the following case:

  1. wlan0 uses queue 0
     (ath10k maps queues per vif)
  2. offchannel uses queue 15
  3. queues 1-14 are unused
  4. ieee80211_stop_queues()
  5. ieee80211_wake_queue(q=0)
  6. ieee80211_wake_queue(q=15)
     (other queues are not woken up because both
      driver and mac80211 know other queues are
      unused)
  7. ieee80211_rx_h_mesh_fwding()
  8. ieee80211_select_queue_80211() returns 2
  9. ieee80211_queue_stopped(q=2) returns true
 10. frame is dropped (oops!)

Fixes: d3c1597b ("mac80211: fix forwarded mesh frame queue mapping")
Signed-off-by: NMichal Kazior <michal.kazior@tieto.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Some drivers offload some frames internally (e.g.
AddBa). Reporting such frames to mac80211 would
only confuse MLME. However it would be useful to
be able to pass such frames to monitor interfaces
for sniffing purposes, e.g. when running AP +
monitor.

To do that allow drivers to tell mac80211 whether
a given frame should be:
 - processed but not delivered to any monitor vif
 - not processed but delievered to monitor vifs
   only
Signed-off-by: NGrzegorz Bajorski <grzegorz.bajorski@tieto.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Add an option for driver to check for packet duplication
by itself.
This is needed for example by the iwlwifi driver which
parallelizes the RX path and does the duplication check
per queue.
Signed-off-by: NSara Sharon <sara.sharon@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The Group ID Management frame is an Action frame of
category VHT. It is transmitted by the AP to assign
or change the user position of a STA for one or more
group IDs.
Process and save the group membership data. Notify
underlying driver of changes.
Signed-off-by: NSara Sharon <sara.sharon@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

An AP can send an operating channel width change in a beacon
opmode notification IE as long as there's a change in the nss as
well (See 802.11ac-2013 section 10.41).
So don't limit updating to nss only from an opmode notification IE.
Signed-off-by: NEyal Shapira <eyalx.shapira@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This really should never happen except very early in the process
of bringing up a new driver, at which point you'll have to add
more debugging in the driver and this string isn't useful. Remove
it and save some size (when it's even compiled in.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Group station statistics by where they're (mostly) updated
(TX, RX and TX-status) and group them into sub-structs of
the struct sta_info.

Also rename the variables since the grouping now makes it
obvious where they belong.

This makes it easier to identify where the statistics are
updated in the code, and thus easier to think about them.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Reduce indentation a bit to make the condition more readable.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Instead of using the out-of-line average calculation, use the new
DECLARE_EWMA() macro to declare a signal EWMA, and use that.

This actually *reduces* the code size slightly (on x86-64) while
also reducing the station info size by 80 bytes.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Currently OCB mode accepts frames with bssid==broadcast and type!=beacon.
Some non-data frames are sent matching this, for example probe responses.
This results in unnecessary creation of STA entries.
Signed-off-by: NBertold Van den Bergh <bertold.vandenbergh@esat.kuleuven.be>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Move TDLS channel-switch Rx handling into an RTNL locked work. This is
required to add proper regulatory checking to incoming channel-switch
requests.
Queue incoming requests in a dedicated skb queue and handle the request
in a device-specific work to avoid deadlocking on interface removal.
Signed-off-by: NArik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There's a long-standing TODO item to use this flag in the cooked
monitor RX, but clearly it was never needed and now this hasn't
been used by userspace for a long time, so no userspace changes
could require it now.

Remove the unused flag.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This counter is inherently racy (since it can be incremented by RX
as well as by concurrent TX) and only available in debugfs. Instead
of fixing it to be per-CPU or similar, remove it for now. If needed
it should be added without races and with proper nl80211, perhaps
even addressing the threshold reporting TODO item that's been there
since the code was originally added.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

As there's no driver using this capability and reporting zero-length
A-MPDU subframes for radiotap monitoring, remove the capability to
free up two RX flags.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When introducing multiple RX queues, a single NAPI struct will not
be sufficient. Instead of trying to store multiple, simply change
the API to have the NAPI struct passed to the RX function. This of
course means that drivers using rx_irqsafe() cannot use NAPI, but
that seems a reasonable trade-off, particularly since only two of
all drivers are currently using it at all.

While at it, we can now remove the IEEE80211_RX_REORDER_TIMER flag
again since this code path cannot have a napi struct anyway.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This function is only used in the RX code, so moving it into
that file gives the compiler better optimisation possibilities
and also allows us to remove the check for short frames (which
in the RX path cannot happen, but as a generic utility needed
to be checked.)
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Short frames less than 16 octets are already blocked in the monitor
code by the should_drop_frame() function, and cannot get into the
regular RX path. Therefore, this check can never trigger and the
counter invariably stays zero. Remove the useless code.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

We typically use 'sta' for the station info struct, and if needed
'pubsta' for the public (driver-visible) portion thereof. Do this
in the ieee80211_sta_ps_transition() function.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

As we're running out of hardware capability flags pretty quickly,
convert them to use the regular test_bit() style unsigned long
bitmaps.

This introduces a number of helper functions/macros to set and to
test the bits, along with new debugfs code.

The occurrences of an explicit __clear_bit() are intentional, the
drivers were never supposed to change their supported bits on the
fly. We should investigate changing this to be a per-frame flag.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

No matter how the driver manages its NAPI context, there's no way
sending frames to it from a timer can be correct, since it would
corrupt the internal GRO lists.

To avoid that, always use the non-NAPI path when releasing frames
from the timer.

Cc: stable@vger.kernel.org
Reported-by: NJean Trivelly <jean.trivelly@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Since these counters can only be read through debugfs, there's
very little point in maintaining them all the time. However,
even just making them depend on debugfs is pointless - they're
not normally used. Additionally a number of them aren't even
concurrency safe.

Move them under MAC80211_DEBUG_COUNTERS so they're normally
not even compiled in.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The debugfs statistics macros are pointlessly verbose, so change
that macro to just have a single argument. While at it, remove
the unused counters and rename rx_expand_skb_head2 to the better
rx_expand_skb_head_defrag.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When frames time out in the reordering buffer, it is a
good indication that something went wrong and the driver
may want to know about that to take action or trigger
debug flows.
It is pointless to notify the driver about each frame that
is released. Notify each time the timer fires.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When we receive a BAR, this typically means that our peer
doesn't hear our Block-Acks or that we can't hear its
frames. Either way, it is a good indication that the link
is in a bad condition. This is why it can serve as a probe
to the driver.
Use the event_callback callback for this.
Since more events with the same data will be added in the
feature, the structure that describes the data attached to
the event is called in a generic name: ieee80211_ba_event.

This also means that from now on, the event_callback can't
sleep.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>