For now, the only module implement is 'sample', and that's only partially
implemented. The main issue here with reusing this structure in userland
is that it uses 'rix' everywhere, which requires the userland code to
have access to the current HAL rate table.
For now, this is a very large work in progress.
Specific details:
* The rate control information is per-node at the moment and wrapped
in a TLV, to ease parsing and backwards compatibility.
* .. but so I can be slack for now, the userland statistics are just
a copy of the kernel-land sample node state.
* However, for now use a temporary copy and change the rix entries
to dot11rate entries to make it slightly easier to eyeball.
Problems:
* The actual rate information table is unfortunately indexed by rix
and it doesn't contain a rate code. So the userland side of this
currently has no way to extract out a mapping.
TODO:
* Add a TLV payload to dump out the rate control table mapping so
'rix' can be turned into a dot11 / MCS rate.
* .. then remove the temporary copy.
the assumption that ath_softc doesn't change size based on build time
configuration.
I picked up on this because suddenly radar stuff didn't work; and
although the ath_dfs code was setting sc_dodfs=1, the main ath driver
saw sc_dodfs=0.
So for now, include opt_ath.h in driver source files. This seems like
the sane thing to do anyway.
I'll have to do a pass over the code at some later stage and turn
the radiotap TX/RX structs into malloc'ed memory, rather than in-line
inside of ath_softc. I'd rather like to keep ath_softc the same
layout regardless of configuration parameters.
Pointy hat to: adrian
for Atheros AR5416 and later wireless devices.
This is a very large commit - the complete history can be
found in the user/adrian/if_ath_tx branch.
Legacy (ie, pre-AR5416) devices also use the per-software
TXQ support and (in theory) can support non-aggregation
ADDBA sessions. However, the net80211 stack doesn't currently
support this.
In summary:
TX path:
* queued frames normally go onto a per-TID, per-node queue
* some special frames (eg ADDBA control frames) are thrown
directly onto the relevant hardware queue so they can
go out before any software queued frames are queued.
* Add methods to create, suspend, resume and tear down an
aggregation session.
* Add in software retransmission of both normal and aggregate
frames.
* Add in completion handling of aggregate frames, including
parsing the block ack bitmap provided by the hardware.
* Write an aggregation function which can assemble frames into
an aggregate based on the selected rate control and channel
configuration.
* The per-TID queues are locked based on their target hardware
TX queue. This matches what ath9k/atheros does, and thus
simplified porting over some of the aggregation logic.
* When doing TX aggregation, stick the sequence number allocation
in the TX path rather than net80211 TX path, and protect it
by the TXQ lock.
Rate control:
* Delay rate control selection until the frame is about to
be queued to the hardware, so retried frames can have their
rate control choices changed. Frames with a static rate
control selection have that applied before each TX, just
to simplify the TX path (ie, not have "static" and "dynamic"
rate control special cased.)
* Teach ath_rate_sample about aggregates - both completion and
errors.
* Add an EWMA for tracking what the current "good" MCS rate is
based on failure rates.
Misc:
* Introduce a bunch of dirty hacks and workarounds so TID mapping
and net80211 frame inspection can be kept out of the net80211
layer. Because of the way this code works (and it's from Atheros
and Linux ath9k), there is a consistent, 1:1 mapping between
TID and AC. So we need to ensure that frames going to a specific
TID will _always_ end up on the right AC, and vice versa, or the
completion/locking will simply get very confused. I plan on
addressing this mess in the future.
Known issues:
* There is no BAR frame transmission just yet. A whole lot of
tidying up needs to occur before BAR frame TX can occur in the
"correct" place - ie, once the TID TX queue has been drained.
* Interface reset/purge/etc results in frames in the TX and RX
queues being removed. This creates holes in the sequence numbers
being assigned and the TX/RX AMPDU code (on either side) just
hangs.
* There's no filtered frame support at the present moment, so
stations going into power saving mode will simply have a number
of frames dropped - likely resulting in a traffic "hang".
* Raw frame TX is going to just not function with 11n aggregation.
Likely this needs to be modified to always override the sequence
number if the frame is going into an aggregation session.
However, general raw frame injection currently doesn't work in
general in net80211, so let's just ignore this for now until
this is sorted out.
* HT protection is just not implemented and won't be until the above
is sorted out. In addition, the AR5416 has issues RTS protecting
large aggregates (anything >8k), so the work around needs to be
ported and tested. Thus, this will be put on hold until the above
work is complete.
* The rate control module 'sample' is the only currently supported
module; onoe/amrr haven't been tested and have likely bit rotted
a little. I'll follow up with some commits to make them work again
for non-11n rates, but they won't be updated to handle 11n and
aggregation. If someone wishes to do so then they're welcome to
send along patches.
* .. and "sample" doesn't really do a good job of 11n TX. Specifically,
the metrics used (packet TX time and failure/success rates) isn't as
useful for 11n. It's likely that it should be extended to take into
account the aggregate throughput possible and then choose a rate
which maximises that. Ie, it may be acceptable for a higher MCS rate
with a higher failure to be used if it gives a more acceptable
throughput/latency then a lower MCS rate @ a lower error rate.
Again, patches will be gratefully accepted.
Because of this, ATH_ENABLE_11N is still not enabled by default.
Sponsored by: Hobnob, Inc.
Obtained from: Linux, Atheros
module; the ath module now brings in the hal support. Kernel
config files are almost backwards compatible; supplying
device ath_hal
gives you the same chip support that the binary hal did but you
must also include
options AH_SUPPORT_AR5416
to enable the extended format descriptors used by 11n parts.
It is now possible to control the chip support included in a
build by specifying exactly which chips are to be supported
in the config file; consult ath_hal(4) for information.
Note this includes changes to all drivers and moves some device firmware
loading to use firmware(9) and a separate module (e.g. ral). Also there
no longer are separate wlan_scan* modules; this functionality is now
bundled into the wlan module.
Supported by: Hobnob and Marvell
Reviewed by: many
Obtained from: Atheros (some bits)
framework for non-MPSAFE network protocols:
- Remove debug_mpsafenet variable, sysctl, and tunable.
- Remove NET_NEEDS_GIANT() and associate SYSINITSs used by it to force
debug.mpsafenet=0 if non-MPSAFE protocols are compiled into the kernel.
- Remove logic to automatically flag interrupt handlers as non-MPSAFE if
debug.mpsafenet is set for an INTR_TYPE_NET handler.
- Remove logic to automatically flag netisr handlers as non-MPSAFE if
debug.mpsafenet is set.
- Remove references in a few subsystems, including NFS and Cronyx drivers,
which keyed off debug_mpsafenet to determine various aspects of their own
locking behavior.
- Convert NET_LOCK_GIANT(), NET_UNLOCK_GIANT(), and NET_ASSERT_GIANT into
no-op's, as their entire behavior was determined by the value in
debug_mpsafenet.
- Alias NET_CALLOUT_MPSAFE to CALLOUT_MPSAFE.
Many remaining references to NET_.*_GIANT() and NET_CALLOUT_MPSAFE are still
present in subsystems, and will be removed in followup commits.
Reviewed by: bz, jhb
Approved by: re (kensmith)
o major overhaul of the way channels are handled: channels are now
fully enumerated and uniquely identify the operating characteristics;
these changes are visible to user applications which require changes
o make scanning support independent of the state machine to enable
background scanning and roaming
o move scanning support into loadable modules based on the operating
mode to enable different policies and reduce the memory footprint
on systems w/ constrained resources
o add background scanning in station mode (no support for adhoc/ibss
mode yet)
o significantly speedup sta mode scanning with a variety of techniques
o add roaming support when background scanning is supported; for now
we use a simple algorithm to trigger a roam: we threshold the rssi
and tx rate, if either drops too low we try to roam to a new ap
o add tx fragmentation support
o add first cut at 802.11n support: this code works with forthcoming
drivers but is incomplete; it's included now to establish a baseline
for other drivers to be developed and for user applications
o adjust max_linkhdr et. al. to reflect 802.11 requirements; this eliminates
prepending mbufs for traffic generated locally
o add support for Atheros protocol extensions; mainly the fast frames
encapsulation (note this can be used with any card that can tx+rx
large frames correctly)
o add sta support for ap's that beacon both WPA1+2 support
o change all data types from bsd-style to posix-style
o propagate noise floor data from drivers to net80211 and on to user apps
o correct various issues in the sta mode state machine related to handling
authentication and association failures
o enable the addition of sta mode power save support for drivers that need
net80211 support (not in this commit)
o remove old WI compatibility ioctls (wicontrol is officially dead)
o change the data structures returned for get sta info and get scan
results so future additions will not break user apps
o fixed tx rate is now maintained internally as an ieee rate and not an
index into the rate set; this needs to be extended to deal with
multi-mode operation
o add extended channel specifications to radiotap to enable 11n sniffing
Drivers:
o ath: add support for bg scanning, tx fragmentation, fast frames,
dynamic turbo (lightly tested), 11n (sniffing only and needs
new hal)
o awi: compile tested only
o ndis: lightly tested
o ipw: lightly tested
o iwi: add support for bg scanning (well tested but may have some
rough edges)
o ral, ural, rum: add suppoort for bg scanning, calibrate rssi data
o wi: lightly tested
This work is based on contributions by Atheros, kmacy, sephe, thompsa,
mlaier, kevlo, and others. Much of the scanning work was supported by
Atheros. The 11n work was supported by Marvell.
o no more ds_vdata in tx/rx descriptors
o split h/w tx/rx descriptor from s/w status
o as part of the descriptor split change the rate control module api
so the ath_buf is passed in to the module so it can fetch both
descriptor and status information as needed
o add some const poisoning
Also for sample rate control algorithm:
o split debug msgs (node, rate, any)
o uniformly bounds check rate indices (and in some cases correct checks)
o move array index ops to after bounds checking
o use final tsi from the status block instead of the h/w descriptor
o replace h/w descriptor struct's with proper mask+shift defs (this
doesn't belong here; everything is known by the driver and should
just be sent down so there's no h/w-specific knowledge)
MFC after: 1 month
IFF_DRV_RUNNING, as well as the move from ifnet.if_flags to
ifnet.if_drv_flags. Device drivers are now responsible for
synchronizing access to these flags, as they are in if_drv_flags. This
helps prevent races between the network stack and device driver in
maintaining the interface flags field.
Many __FreeBSD__ and __FreeBSD_version checks maintained and continued;
some less so.
Reviewed by: pjd, bz
MFC after: 7 days
struct ifnet or the layer 2 common structure it was embedded in have
been replaced with a struct ifnet pointer to be filled by a call to the
new function, if_alloc(). The layer 2 common structure is also allocated
via if_alloc() based on the interface type. It is hung off the new
struct ifnet member, if_l2com.
This change removes the size of these structures from the kernel ABI and
will allow us to better manage them as interfaces come and go.
Other changes of note:
- Struct arpcom is no longer referenced in normal interface code.
Instead the Ethernet address is accessed via the IFP2ENADDR() macro.
To enforce this ac_enaddr has been renamed to _ac_enaddr.
- The second argument to ether_ifattach is now always the mac address
from driver private storage rather than sometimes being ac_enaddr.
Reviewed by: sobomax, sam
to the rate control module for tx complete processing; this enables
rate control algorithms to extract the packet length for xmits that
require multiple descriptors
of a sizeof, need to use %z to get the correct type on all our platforms.
Also, convert integers<->pointers via uintptr_t.
(I think Sam's instructions were for me to commit this. If I
misunderstood, then I apologize in advance.)
