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>

The conversion to the fast-xmit path lost proper aggregation session
timeout handling - the last_tx wasn't set on that path and the timer
would therefore incorrectly tear down the session periodically (with
those drivers/rate control algorithms that have a timeout.)

In case of iwlwifi, this was every 5 seconds and caused significant
throughput degradation.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

For drivers supporting TSO or similar features, but that still have
PN assignment in software, there's a need to have some memory to
store the current PN value. As mac80211 already stores this and it's
somewhat complicated to add a per-driver area to the key struct (due
to the dynamic sizing thereof) it makes sense to just move the TX PN
to the keyconf, i.e. the public part of the key struct.

As TKIP is more complicated and we won't able to offload it in this
way right now (fast-xmit is skipped for TKIP unless the HW does it
all, and our hardware needs MMIC calculation in software) I've not
moved that for now - it's possible but requires exposing a lot of
the internal TKIP state.

As an bonus side effect, we can remove a lot of code by assuming the
keyseq struct has a certain layout - with BUILD_BUG_ON to verify it.

This might also improve performance, since now TX and RX no longer
share a cacheline.
Reviewed-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

No current (and planned, as far as I know) wifi devices support
encapsulation checksum offload, so remove the useless test here.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

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: NJohannes Berg <johannes.berg@intel.com>

This isn't all that relevant for RX right now, but TX can be concurrent
due to multi-queue and the accounting is therefore broken.

Use the standard per-CPU statistics to avoid this.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This isn't necessary any more as the stack will automatically
update the TXQ's trans_start after calling ndo_start_xmit().
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Implement the necessary software segmentation on the normal
TX path so that fast-xmit can use segmentation offload if
the hardware (or driver) supports it.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If drivers want to support S/G (really just gather DMA on TX) then
we can now easily support this on the fast-xmit path since it just
needs to write to the ethernet header (and already has a check for
that being possible.)

However, disallow this on the regular TX path (which has to handle
fragmentation, software crypto, etc.) by calling skb_linearize().

Also allow the related HIGHDMA since that's not interesting to the
code in mac80211 at all anyway.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When we go through the complete TX processing, there are a number
of things like fragmentation and software crypto that require the
checksum to be calculated already.

In favour of maintainability, instead of adding the necessary call
to skb_checksum_help() in all the places that need it, just do it
once before the regular TX processing.

Right now this only affects the TI wlcore and QCA ath10k drivers
since they're the only ones using checksum offload. The previous
commits enabled fast-xmit for them in almost all cases.

For wlcore this even fixes a corner case: when a key fails to be
programmed to hardware software encryption gets used, encrypting
frames with a bad checksum.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

IBSS can be supported very easily since it uses the standard station
authorization state etc. so it just needs to be covered by the header
building switch statement.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

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: NJohannes Berg <johannes.berg@intel.com>

If the driver handles fragmentation then it wouldn't
be done in software so we can still use the fast-xmit
path in that case.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

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: NJohannes Berg <johannes.berg@intel.com>

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: NFelix Fietkau <nbd@openwrt.org>
[resolved minor context conflict, minor changes, endian annotations]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

In order to look up the RA station earlier to implement a TX
fastpath, factor out the lookup from ieee80211_build_hdr().
To always have a valid station pointer, also move some of the
checks into the new function.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Indicating just the peer's capability is fairly pointless
if the local device doesn't support it. Make the variable
track both combined, and remove the 'local support' check
in the TX path.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Instead of looking up the destination station twice in the TX path
(first to build the header, and then for control processing), save
it when building the header and use it later in the TX path.

To avoid having to look up the station in the many callers, allow
those to pass %NULL which keeps the existing lookup.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

In ieee80211_build_hdr(), the station is looked up to build the
header correctly (QoS field) and to check for authorization. For
mesh, authorization isn't checked here, and QoS capability is
mandatory, so the station lookup can be avoided.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

If there's no station on the 4-addr VLAN interface, then frames
cannot be transmitted. Drop such frames earlier, before setting
up all the information for them.

We should keep the old check though since that code might be used
for other internally-generated frames.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

There's no need to look up the destination station twice while
building the 802.11 header for a given frame if the frame will
actually be transmitted to the station we initially looked up.

This happens for 4-addr VLAN interfaces and TDLS connections, which
both directly send the frame to the station they looked up, though
in the case of TDLS some station conditions need to be checked.

To avoid that, add a variable indicating that we've looked up the
station that the frame is going to be transmitted to, and avoid the
lookup/flag checking if it already has been done.

In the TDLS case, also move the authorized/wme_sta flag assignment
to the correct place, i.e. only when that station is really used.
Before this change, the new lookup should always have succeeded so
that the potentially erroneous data would be overwritten.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This mechanism was historic, and only ever used by IBSS, which
also doesn't need to have it as it properly manages station's
802.1X PAE state (or, with WEP, always has a key.)

Remove the mechanism to clean up the code.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The ieee80211_tx_prepare_skb() function currently entirely ignores
the fact that the SKB that is passed in might be split into more
than one due to fragmentation and doesn't check the list of skbs
that the TX handlers may create. In case this happens, it would
leak them.

Fix this and also don't leave the skb next/prev pointers dangling
pointing to the on-stack sk_buff_head.
Reported-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Revert commit ad38bfc9 ("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: NJohannes Berg <johannes.berg@intel.com>

Since multicast addresses don't exist as stations, don't attempt
to look them up in the hashtable on TX.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

The current minstrel_ht rate control behavior is somewhat optimistic in
trying to find optimum TX rate. While this is usually fine for normal
Data frames, there are cases where a more conservative set of retry
parameters would be beneficial to make the connection more robust.

EAPOL frames are critical to the authentication and especially the
EAPOL-Key message 4/4 (the last message in the 4-way handshake) is
important to get through to the AP. If that message is lost, the only
recovery mechanism in many cases is to reassociate with the AP and start
from scratch. This can often be avoided by trying to send the frame with
more conservative rate and/or with more link layer retries.

In most cases, minstrel_ht is currently using the initial EAPOL-Key
frames for probing higher rates and this results in only five link layer
transmission attempts (one at high(ish) MCS and four at MCS0). While
this works with most APs, it looks like there are some deployed APs that
may have issues with the EAPOL frames using HT MCS immediately after
association. Similarly, there may be issues in cases where the signal
strength or radio environment is not good enough to be able to get
frames through even at couple of MCS 0 tries.

The best approach for this would likely to be to reduce the TX rate for
the last rate (3rd rate parameter in the set) to a low basic rate (say,
6 Mbps on 5 GHz and 2 or 5.5 Mbps on 2.4 GHz), but doing that cleanly
requires some more effort. For now, we can start with a simple one-liner
that forces the minimum rate to be used for EAPOL frames similarly how
the TX rate is selected for the IEEE 802.11 Management frames. This does
result in a small extra latency added to the cases where the AP would be
able to receive the higher rate, but taken into account how small number
of EAPOL frames are used, this is likely to be insignificant. A future
optimization in the minstrel_ht design can also allow this patch to be
reverted to get back to the more optimized initial TX rate.

It should also be noted that many drivers that do not use minstrel as
the rate control algorithm are already doing similar workarounds by
forcing the lowest TX rate to be used for EAPOL frames.

Cc: stable@vger.kernel.org
Reported-by: NLinus Torvalds <torvalds@linux-foundation.org>
Tested-by: NLinus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This allows mac80211 to configure BIP-GMAC-128 and BIP-GMAC-256 to the
driver and also use software-implementation within mac80211 when the
driver does not support this with hardware accelaration.
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This allows mac80211 to configure BIP-CMAC-256 to the driver and also
use software-implementation within mac80211 when the driver does not
support this with hardware accelaration.
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This allows mac80211 to configure CCMP-256 to the driver and also use
software-implementation within mac80211 when the driver does not support
this with hardware accelaration.
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
[squash ccmp256 -> mic_len argument change]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This allows mac80211 to configure GCMP and GCMP-256 to the driver and
also use software-implementation within mac80211 when the driver does
not support this with hardware accelaration.
Signed-off-by: NJouni Malinen <jouni@qca.qualcomm.com>
[remove a spurious newline]
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

When roaming / suspending, it makes no sense to wait until
the transmit queues of the device are empty. In extreme
condition they can be starved (VO saturating the air), but
even in regular cases, it is pointless to delay the roaming
because the low level driver is trying to send packets to
an AP which is far away. We'd rather drop these packets and
let TCP retransmit if needed. This will allow to speed up
the roaming.

For suspend, the explanation is even more trivial.
Signed-off-by: NEmmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

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: NJohannes Berg <johannes.berg@intel.com>

Fixes a crash on attempting to calculate the frame duration for a VHT
packet (which needs to be handled by hw/driver instead).
Reported-by: NJouni Malinen <j@w1.fi>
Signed-off-by: NFelix Fietkau <nbd@openwrt.org>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Allow drivers to support NL80211_SCAN_FLAG_RANDOM_ADDR with software
based scanning and generate a random MAC address for them for every
scan request with the flag.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

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: NLiad Kaufman <liad.kaufman@intel.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

For some TDLS channel switch implementations data frames need to be
sent by the firmware based on a template. This template should be
created by mac80211, and thus needs to properly be built from an
802.3 frame into an 802.11 frame. In addition, the device will need
the key information so the select_key handler needs to be run.
However, the driver/device will be responsible for all of the crypto
encapsulation, as the sequence numbers etc. cannot be built by the
host anyway in this case since it's a template to be used multiple
times.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NArik Nemtsov <arik@wizery.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Factor out the 802.11 header building code from the xmit function
to be able to use it separately in a later commit.

While at it, fix up some documentation.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NArik Nemtsov <arik@wizery.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Instead of passing the band as a parameter to ieee80211_xmit()
and ieee80211_tx(), move it outside of the two functions while
making sure info->band is set up before calling them.

This removes the parameter and simplifies the follow commit.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NArik Nemtsov <arik@wizery.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

Allows setting of an skb's flags - if needed - when calling
ieee80211_subif_start_xmit().
Signed-off-by: NLiad Kaufman <liad.kaufman@intel.com>
Signed-off-by: NArik Nemtsov <arik@wizery.com>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>

This patch adds 802.11p OCB (Outside the Context of a BSS) mode
support.

When communicating in OCB mode a mandatory wildcard BSSID
(48 '1' bits) is used.

The EDCA parameters handling function was changed to support
802.11p specific values.

The insertion of a newly discovered STAs is done in the similar way
as in the IBSS mode -- through the deferred insertion.

The OCB mode uses a periodic 'housekeeping task' for expiration of
disconnected STAs (in the similar manner as in the MESH mode).

New Kconfig option for verbose OCB debugging outputs is added.
Signed-off-by: NRostislav Lisovy <rostislav.lisovy@fel.cvut.cz>
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>