Commit Graph

238 Commits

Author SHA1 Message Date
Herbert Xu 83e7e4ce9e mac80211: Use rhltable instead of rhashtable
mac80211 currently uses rhashtable with insecure_elasticity set
to true.  The latter is because of duplicate objects.  What's
more, mac80211 walks the rhashtable chains by hand which is broken
as rhashtable may contain multiple tables due to resizing or
rehashing.

This patch fixes it by converting it to the newly added rhltable
interface which is designed for use with duplicate objects.

With rhltable a lookup returns a list of objects instead of a
single one.  This is then fed into the existing for_each_sta_info
macro.

This patch also deletes the sta_addr_hash function since rhashtable
defaults to jhash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-20 04:43:36 -04:00
Johannes Berg bfe40fa395 mac80211: send delBA on unexpected BlockAck data frames
When we receive data frames with ACK policy BlockAck, send
delBA as requested by the 802.11 spec. Since this would be
happening for every frame inside an A-MPDU if it's really
received outside a session, limit it to a single attempt.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-09-12 11:46:21 +02:00
Maxim Altshul 3b17fbf87d mac80211: mesh: Add support for HW RC implementation
Mesh HWMP module will be able to rely on the HW
RC algorithm if it exists, for path metric calculations.

This allows the metric calculation mechanism to calculate
a correct metric, based on PER and last TX rate both via
HW RC algorithm if it exists or via parameters collected
by the SW.

Signed-off-by: Maxim Altshul <maxim.altshul@ti.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-08-11 16:51:40 +02:00
Felix Fietkau 6fe04128f1 mac80211: fix fast_tx header alignment
The header field is defined as u8[] but also accessed as struct
ieee80211_hdr. Enforce an alignment of 2 to prevent unnecessary
unaligned accesses, which can be very harmful for performance on many
platforms.

Fixes: e495c24731 ("mac80211: extend fast-xmit for more ciphers")
Cc: stable@vger.kernel.org
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-05-31 12:14:04 +02:00
David S. Miller ae95d71261 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-04-09 17:41:41 -04:00
Johannes Berg c9c5962b56 mac80211: enable collecting station statistics per-CPU
If the driver advertises the new HW flag USE_RSS, make the
station statistics on the fast-rx path per-CPU. This will
enable calling the RX in parallel, only hitting locking or
shared cachelines when the fast-RX path isn't available.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-04-06 13:18:19 +02:00
Johannes Berg 49ddf8e6e2 mac80211: add fast-rx path
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: Johannes Berg <johannes.berg@intel.com>
2016-04-06 13:18:18 +02:00
Johannes Berg 0f9c5a61d4 mac80211: fix RX u64 stats consistency on 32-bit platforms
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: Johannes Berg <johannes.berg@intel.com>
2016-04-06 13:18:17 +02:00
Johannes Berg 4f6b1b3daa mac80211: fix last RX rate data consistency
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: Johannes Berg <johannes.berg@intel.com>
2016-04-06 13:18:17 +02:00
Johannes Berg b8da6b6a99 mac80211: add separate last_ack variable
Instead of touching the rx_stats.last_rx from the status path, introduce
and use a status_stats.last_ack variable. This will make rx_stats.last_rx
indicate when the last frame was received, making it available for real
"last_rx" and statistics gathering; statistics, when done per-CPU, will
need to figure out which place was updated last for those items where the
"last" value is exposed.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-04-06 13:18:16 +02:00
Johannes Berg 0be6ed1338 mac80211: move averaged values out of rx_stats
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: Johannes Berg <johannes.berg@intel.com>
2016-04-06 13:18:15 +02:00
Johannes Berg c84387d2f2 mac80211: clean up station flags debugfs
Avoid the really strange %s%s%s expression, use an array
of flag names and check that all flags are present.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-04-05 12:12:26 +02:00
Johannes Berg fc4a25c5b7 mac80211: remove sta_info debugfs sub-struct
Since the previous patch, the struct only has a single member,
so remove the struct and leave just the single member.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-04-05 11:59:05 +02:00
Mohammed Shafi Shajakhan 96f321c9d4 mac80211: Remove unused variable in per STA debugfs struct
Remove unused variable in per STA debugfs structure, 'commit 34e895075e
("mac80211: allow station add/remove to sleep")' removed the only user of
'add_has_run'.

Signed-off-by: Mohammed Shafi Shajakhan <mohammed@qti.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-04-05 11:57:11 +02:00
Luis de Bethencourt c2d45923e3 mac80211: remove description of dropped member
Commit 976bd9efda ("mac80211: move beacon_loss_count into ifmgd")
removed the member from the sta_info struct but the description stayed
lingering. Remove it.

Signed-off-by: Luis de Bethencourt <luisbg@osg.samsung.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-04-05 11:12:09 +02:00
Sara Sharon 06470f7468 mac80211: add API to allow filtering frames in BA sessions
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: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-02-24 09:04:31 +01:00
Sara Sharon 412a6d800c mac80211: support hw managing reorder logic
Enable driver to manage the reordering logic itself.
This is needed for example for the iwlwifi driver that
will support hardware assisted reordering.

Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2016-02-24 09:04:16 +01:00
Eliad Peller ef044763a3 mac80211: add atomic uploaded keys iterator
add ieee80211_iter_keys_rcu() to iterate over uploaded
keys in atomic context (when rcu is locked)

The station removal code removes the keys only after
calling synchronize_net(), so it's not safe to iterate
the keys at this point (and postponing the actual key
deletion with call_rcu() might result in some
badly-ordered ops calls).

Add a flag to indicate a station is being removed,
and skip the configured keys if it's set.

Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-12-04 14:43:32 +01:00
Johannes Berg e5a9f8d046 mac80211: move station statistics into sub-structs
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: Johannes Berg <johannes.berg@intel.com>
2015-10-21 10:08:22 +02:00
Johannes Berg 976bd9efda mac80211: move beacon_loss_count into ifmgd
There's little point in keeping (and even sending to userspace)
the beacon_loss_count value per station, since it can only apply
to the AP on a managed-mode connection. Move the value to ifmgd,
advertise it only in managed mode, and remove it from ethtool as
it's available through better interfaces.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-10-21 10:08:21 +02:00
Johannes Berg 763aa27a29 mac80211: remove sta->last_ack_signal
This file only feeds a debugfs file that isn't very useful, so remove
it. If necessary, we can add other ways to get this information, for
example in the NL80211_CMD_PROBE_CLIENT response.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-10-21 10:08:21 +02:00
Johannes Berg fbd6ff5cea mac80211: move sta_set_rate_info_rx() and make it static
There's only a single caller of this function, so it can
be moved to the same file and made static.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-10-14 18:31:30 +02:00
Emmanuel Grumbach e3abc8ff0f mac80211: allow to transmit A-MSDU within A-MPDU
Advertise the capability to send A-MSDU within A-MPDU
in the AddBA request sent by mac80211. Let the driver
know about the peer's capabilities.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-09-22 15:21:23 +02:00
Johannes Berg 40d9a38ad3 mac80211: use DECLARE_EWMA
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: Johannes Berg <johannes.berg@intel.com>
2015-08-14 17:49:53 +02:00
Bob Copeland a69bd8e60b mac80211: mesh: separate plid and aid concepts
According to 802.11-2012 13.3.1, a mesh STA should assign an AID
upon receipt of a mesh peering open frame rather than using the link
id of the peer.  Using the peer link id has two potential issues:
it may not be unique among the peers, and by its nature it is random,
so the TIM may not compress well.

In preparation for allocating it properly, use sta->sta.aid, but keep
the existing behavior of using the plid in the aid we send.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:47:11 +02:00
Johannes Berg a76d5e0a23 mac80211: mesh: move fail_avg into mesh struct
This value is only used in mesh, so move it into the new mesh
sub-struct of the station info.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:38:24 +02:00
Arik Nemtsov 0fabfaafec mac80211: upgrade BW of TDLS peers when possible
Define a station chandef, to be used for wider-bw TDLS peers. When both
peers support the feature, upgrade the channel bandwidth to the maximum
allowed by both peers and regulatory. Currently widths up to 80MHz are
supported in the 5GHz band.

When a TDLS peer connects/disconnects recalculate the channel type of the
current chanctx.
Make the chanctx width calculation consider wider-bw TDLS peers and
similarly fix the max_required_bw calculation for the chanctx min_def.
Since the sta->bandwidth is calculated only later on, take
bss_conf.chandef.width as the minimal width for station interface.

Set the upgraded channel width in the VHT-operation set during TDLS setup.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:38:12 +02:00
Arik Nemtsov b98fb44ffc mac80211: define TDLS wider BW support bits
Allow a device to specify support for the TDLS wider-bandwidth feature.
Indicate this support during TDLS setup in the ext-capab IE and set an
appropriate station flag when our TDLS peer supports it.
This feature gives TDLS peers the ability to use a wider channel than
the base width of the BSS. For instance VHT capable TDLS peers connected
on a 20MHz channel can extend the channel to 80MHz, if regulatory
considerations allow it.

Do not cap the bandwidth of such stations by the current BSS channel width
in mac80211.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:38:11 +02:00
Johannes Berg 433f5bc1c0 mac80211: move mesh related station fields to own struct
There are now a fairly large number of mesh fields that really
aren't needed in any other modes; move those into their own
structure and allocate them separately.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:38:06 +02:00
Johannes Berg ac100ce52a mac80211: duplicate station's MAC address for hash table
Currently, the station hash table lookup (or iteration) must
access two cachelines for each station - the one with the hash
table node, and the one with the MAC address.

Duplicate the MAC address next to the hash node to get rid of
this. Since the MAC address is static there's no consistency
problem introduced by this.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:38:03 +02:00
Johannes Berg 798a457dfb mac80211: fix comment referring to RX queue
There are no RX queues in mac80211 (yet), the comment should refer
to the TID (including one slot for non-QoS) rather than 'RX queue'.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:37:58 +02:00
Johannes Berg 16bf948081 mac80211: remove sta_info.gtk_idx
This struct member is only assigned, never used otherwise;
remove it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-07-17 15:37:54 +02:00
Alexis Green e060e7adc2 mac80211: Always check rates and capabilities in mesh mode
In mesh mode there is a race between establishing links and processing
rates and capabilities in beacons. This is very noticeable with slow
beacons (e.g. beacon intervals of 1s) and manifested for us as stations
using minstrel when minstrel_ht should be used. Fixed by changing
mesh_sta_info_init so that it always checks rates and such if it has not
already done so.

Signed-off-by: Alexis Green <agreen@cococorp.com>
CC: Jesse Jones <jjones@cococorp.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-06-09 22:05:06 +02:00
Johannes Berg bbbe8c8c59 mac80211: add missing documentation for rate_ctrl_lock
This was missed in the previous patch, add some documentation
for rate_ctrl_lock to avoid docbook warnings.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-05-06 16:00:32 +02:00
Johannes Berg f83f1c129a mac80211: remove sta->tx_fragments counter
This counter is unsafe with concurrent TX and is only exposed
through debugfs and ethtool. Instead of trying to fix it just
remove it for now, if it's really needed then it should be
exposed through nl80211 and in a way that drivers that do the
fragmentation in the device could support it as well.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-05-05 14:21:55 +02:00
Johannes Berg e495c24731 mac80211: extend fast-xmit for more ciphers
When crypto is offloaded then in some cases it's all handled
by the device, and in others only some space for the IV must
be reserved in the frame. Handle both of these cases in the
fast-xmit path, up to a limit of 18 bytes of space for IVs.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-04-22 10:07:37 +02:00
Johannes Berg 17c18bf880 mac80211: add TX fastpath
In order to speed up mac80211's TX path, add the "fast-xmit" cache
that will cache the data frame 802.11 header and other data to be
able to build the frame more quickly. This cache is rebuilt when
external triggers imply changes, but a lot of the checks done per
packet today are simplified away to the check for the cache.

There's also a more detailed description in the code.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-04-22 10:02:25 +02:00
Johannes Berg 35c347ac53 mac80211: lock rate control
Both minstrel (reported by Sven Eckelmann) and the iwlwifi rate
control aren't properly taking concurrency into account. It's
likely that the same is true for other rate control algorithms.

In the case of minstrel this manifests itself in crashes when an
update and other data access are run concurrently, for example
when the stations change bandwidth or similar. In iwlwifi, this
can cause firmware crashes.

Since fixing all rate control algorithms will be very difficult,
just provide locking for invocations. This protects the internal
data structures the algorithms maintain.

I've manipulated hostapd to test this, by having it change its
advertised bandwidth roughly ever 150ms. At the same time, I'm
running a flood ping between the client and the AP, which causes
this race of update vs. get_rate/status to easily happen on the
client. With this change, the system survives this test.

Reported-by: Sven Eckelmann <sven@open-mesh.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-04-20 13:05:29 +02:00
Bob Copeland 48bf6beddf mac80211: introduce plink lock for plink fields
The mesh plink code uses sta->lock to serialize access to the
plink state fields between the peer link state machine and the
peer link timer.  Some paths (e.g. those involving
mps_qos_null_tx()) unfortunately hold this spinlock across
frame tx, which is soon to be disallowed.  Add a new spinlock
just for plink access.

Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-04-20 13:05:29 +02:00
David S. Miller 4e78eb0dbf There isn't much left, but we have
* new mac80211 internal software queue to allow drivers to have
    shorter hardware queues and pull on-demand
  * use rhashtable for mac80211 station table
  * minstrel rate control debug improvements and some refactoring
  * fix noisy message about TX power reduction
  * fix continuous message printing and activity if CRDA doesn't respond
  * fix VHT-related capabilities with "iw connect" or "iwconfig ..."
  * fix Kconfig for cfg80211 wireless extensions compatibility
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Merge tag 'mac80211-next-for-davem-2015-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next

Johannes Berg says:

====================
There isn't much left, but we have
 * new mac80211 internal software queue to allow drivers to have
   shorter hardware queues and pull on-demand
 * use rhashtable for mac80211 station table
 * minstrel rate control debug improvements and some refactoring
 * fix noisy message about TX power reduction
 * fix continuous message printing and activity if CRDA doesn't respond
 * fix VHT-related capabilities with "iw connect" or "iwconfig ..."
 * fix Kconfig for cfg80211 wireless extensions compatibility
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-12 20:43:46 -04:00
David S. Miller 9f0d34bc34 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/usb/asix_common.c
	drivers/net/usb/sr9800.c
	drivers/net/usb/usbnet.c
	include/linux/usb/usbnet.h
	net/ipv4/tcp_ipv4.c
	net/ipv6/tcp_ipv6.c

The TCP conflicts were overlapping changes.  In 'net' we added a
READ_ONCE() to the socket cached RX route read, whilst in 'net-next'
Eric Dumazet touched the surrounding code dealing with how mini
sockets are handled.

With USB, it's a case of the same bug fix first going into net-next
and then I cherry picked it back into net.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-02 16:16:53 -04:00
Felix Fietkau ba8c3d6f16 mac80211: add an intermediate software queue implementation
This allows drivers to request per-vif and per-sta-tid queues from which
they can pull frames. This makes it easier to keep the hardware queues
short, and to improve fairness between clients and vifs.

The task of scheduling packet transmission is left up to the driver -
queueing is controlled by mac80211. Drivers can only dequeue packets by
calling ieee80211_tx_dequeue. This makes it possible to add active queue
management later without changing drivers using this code.

This can also be used as a starting point to implement A-MSDU
aggregation in a way that does not add artificially induced latency.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
[resolved minor context conflict, minor changes, endian annotations]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-04-01 20:44:34 +02:00
Johannes Berg 788211d81b mac80211: fix RX A-MPDU session reorder timer deletion
There's an issue with the way the RX A-MPDU reorder timer is
deleted that can cause a kernel crash like this:

 * tid_rx is removed - call_rcu(ieee80211_free_tid_rx)
 * station is destroyed
 * reorder timer fires before ieee80211_free_tid_rx() runs,
   accessing the station, thus potentially crashing due to
   the use-after-free

The station deletion is protected by synchronize_net(), but
that isn't enough -- ieee80211_free_tid_rx() need not have
run when that returns (it deletes the timer.) We could use
rcu_barrier() instead of synchronize_net(), but that's much
more expensive.

Instead, to fix this, add a field tracking that the session
is being deleted. In this case, the only re-arming of the
timer happens with the reorder spinlock held, so make that
code not rearm it if the session is being deleted and also
delete the timer after setting that field. This ensures the
timer cannot fire after ___ieee80211_stop_rx_ba_session()
returns, which fixes the problem.

Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-04-01 14:35:01 +02:00
Johannes Berg 7bedd0cfad mac80211: use rhashtable for station table
We currently have a hand-rolled table with 256 entries and are
using the last byte of the MAC address as the hash. This hash
is obviously very fast, but collisions are easily created and
we waste a lot of space in the common case of just connecting
as a client to an AP where we just have a single station. The
other common case of an AP is also suboptimal due to the size
of the hash table and the ease of causing collisions.

Convert all of this to use rhashtable with jhash, which gives
us the advantage of a far better hash function (with random
perturbation to avoid hash collision attacks) and of course
that the hash table grows and shrinks dynamically with chain
length, improving both cases above.

Use a specialised hash function (using jhash, but with fixed
length) to achieve better compiler optimisation as suggested
by Sergey Ryazanov.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-04-01 10:06:26 +02:00
Johannes Berg abfbc3af57 mac80211: remove TX latency measurement code
Revert commit ad38bfc916 ("mac80211: Tx frame latency statistics")
(along with some follow-up fixes).

This code turned out not to be as useful in the current form as we
thought, and we've internally hacked it up more, but that's not
very suitable for upstream (for now), and we might just do that
with tracing instead.

Therefore, for now at least, remove this code. We might also need
to use the skb->tstamp field for the TCP performance issue, which
is more important than the debugging.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-02-28 21:31:11 +01:00
Johannes Berg 79c892b850 mac80211: provide per-TID RX/TX MSDU counters
Implement the new counters cfg80211 can now advertise to userspace.
The TX code is in the sequence number handler, which is a bit odd,
but that place already knows the TID and frame type, so it was
easiest and least impact there.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2015-01-08 15:28:20 +01:00
Liad Kaufman b6da911b3c mac80211: synchronously reserve TID per station
In TDLS (e.g., TDLS off-channel) there is a requirement for
some drivers to supply an unused TID between the AP and the
device to the FW, to allow sending PTI requests and to allow
the FW to aggregate on a specific TID for better throughput.

To ensure that the allocated TID is indeed unused, this patch
introduces an API for blocking the driver from TXing on that
TID.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-11-19 18:45:36 +01:00
Arik Nemtsov a7a6bdd067 mac80211: introduce TDLS channel switch ops
Implement the cfg80211 TDLS channel switch ops and introduce new mac80211
ones for low-level drivers.
Verify low-level driver support for the new ops when using the relevant
wiphy feature bit. Also verify the peer supports channel switching before
passing the command down.

Add a new STA flag to track the off-channel state with the TDLS peer and
make sure to cancel the channel-switch if the peer STA is unexpectedly
removed.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-11-19 18:45:21 +01:00
Arik Nemtsov 9041c1fa57 mac80211: track AP and peer STA TDLS chan-switch support
The AP or peer can prohibit TDLS channel switch via a bit in the
extended capabilities IE. Parse the IE and track this bit. Set an
appropriate STA flag if both the AP and peer STA support TDLS
channel-switching.

Add the new STA flag and the missing TDLS_INITIATOR to debugfs.

Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Arik Nemtsov <arik@wizery.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-11-19 18:45:04 +01:00
Liad Kaufman 8975ae88e1 mac80211: fix warning on htmldocs for last_tdls_pkt_time
Forgot to add an entry to the struct description of sta_info.

Signed-off-by: Liad Kaufman <liad.kaufman@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2014-10-09 10:33:29 +02:00