During roaming, the crypto_tx_tailroom_needed_cnt counter
will often take values 2,1,0,1,2 because first keys are
removed and then new keys are added. This is inefficient
because during the 0->1 transition, synchronize_net must
be called to avoid packet races, although typically no
packets would be flowing during that time.

To avoid that, defer the decrement (2->1, 1->0) when keys
are removed (by half a second). This means the counter
will really have the values 2,2,2,3,4 ... 2, thus never
reaching 0 and having to do the 0->1 transition.

Note that this patch entirely disregards the drivers for
which this optimisation was done to start with, for them
the key removal itself will be expensive because it has
to synchronize_net() after the counter is incremented to
remove the key from HW crypto. For them the sequence will
look like this: 0,1,0,1,0,1,0,1,0 (*) which is clearly a
lot more inefficient. This could be addressed separately,
during key removal the 0->1->0 sequence isn't necessary.

(*) it starts at 0 because HW crypto is on, then goes to
    1 when HW crypto is disabled for a key, then back to
    0 because the key is deleted; this happens for both
    keys in the example. When new keys are added, it goes
    to 1 first because they're added in software; when a
    key is moved to hardware it goes back to 0
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

There's no driver using this flag, so it seems
that all drivers support HW crypto with WMM or
don't support it at all. Remove the flag and
code setting it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Remove not used any longer suspend/resume code.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Remove not used any longer suspend/resume code.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Remove not used any longer suspend/resume code.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Since now we disconnect before suspend, various code which save
connection state can now be removed from suspend and resume
procedure. Cleanup on resume side is smaller as ieee80211_reconfig()
is also used for H/W restart.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If possible that after suspend, cfg80211 will receive request to
disconnect what require action on interface that was removed during
suspend.

Problem can manifest itself by various warnings similar to below one:

WARNING: at net/mac80211/driver-ops.h:12 ieee80211_bss_info_change_notify+0x2f9/0x300 [mac80211]()
wlan0:  Failed check-sdata-in-driver check, flags: 0x4
Call Trace:
 [<c043e0b3>] warn_slowpath_fmt+0x33/0x40
 [<f83707c9>] ieee80211_bss_info_change_notify+0x2f9/0x300 [mac80211]
 [<f83a660a>] ieee80211_recalc_ps_vif+0x2a/0x30 [mac80211]
 [<f83a6706>] ieee80211_set_disassoc+0xf6/0x500 [mac80211]
 [<f83a9441>] ieee80211_mgd_deauth+0x1f1/0x280 [mac80211]
 [<f8381b36>] ieee80211_deauth+0x16/0x20 [mac80211]
 [<f8261e70>] cfg80211_mlme_down+0x70/0xc0 [cfg80211]
 [<f8264de1>] __cfg80211_disconnect+0x1b1/0x1d0 [cfg80211]

To fix the problem disconnect from any associated network before
suspend. User space is responsible to establish connection again
after resume. This basically need to be done by user space anyway,
because associated stations can go away during suspend (for example
NetworkManager disconnects on suspend and connect on resume by default).

Patch also handle situation when driver refuse to suspend with wowlan
configured and try to suspend again without it.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Since two years no mac80211 driver implement support for NAPI. Looks
this feature is unneeded, so remove it from generic mac80211 code.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

A sample attempt should only count in mi->sample_tries if the sample
attempt wasn't skipped based on slower rate criteria.
This patch increases the sampling frequency for potentially desirable
rates and thus enables faster recovery from interference or collisions.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If a rate is below the max_tp_rate, sample it frequently if:
- it is above max_tp_rate2, or
- it is above max_prob_rate and is a candidate for max_prob_rate
  (has fewer streams than max_tp_rate).
This helps the retry chain recover more quickly from bad statistics
caused by collisions or interference, and slightly reduces throughput
fluctuations with higher rates.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Try to sample all available rates, as sample attempts do not cost much
airtime and are appropriately spaced based on the average A-MPDU length.
This helps with faster recovery on rate fluctuations.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

max_prob_rate should be selected to be very reliable, however limiting
it to single-stream on 3-stream devices is a bit much.
Allow max_prob_rate to use one stream less than the max_tp_rate.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

At high data rates the average frame transmission durations are small
enough for rounding errors to matter, sometimes causing minstrel to use
slightly lower transmit rates than necessary.
To fix this, change the unit of the duration value to nanoseconds
instead of microseconds, and reorder the multiplications/divisions when
calculating the throughput metric so that they don't overflow or
truncate prematurely.
At 2-stream HT40 this makes TCP throughput a bit more stable.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add NL80211_CMD_UPDATE_FT_IES to support update of FT IEs to the WLAN
driver and NL80211_CMD_FT_EVENT to send FT events from the WLAN driver.
This will carry the target AP's MAC address along with the relevant
Information Elements. This event is used to report received FT IEs
(MDIE, FTIE, RSN IE, TIE, RICIE). These changes allow FT to be supported
with drivers that use an internal SME instead of user space option (like
FT implementation in wpa_supplicant with mac80211-based drivers).
Signed-off-by: Jouni Malinen <jouni@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

It's not useful to specify a 0 keepalive interval, this
would send too much data. Prohibit this to also avoid
device issues.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Some devices can handle remain on channel requests differently
based on the request type/priority. Add support to
differentiate between different ROC types, i.e., indicate that
the ROC is required for sending managment frames.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Reviewed-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

cfg80211_mlme_assoc() has grown far too many arguments,
make the caller build almost all of the driver struct
and pass that to the function instead.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Support the cfg80211 API to override VHT capabilities
on association.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

For testing it's sometimes useful to be able to
override certain VHT capability advertisement,
add the ability to do that in cfg80211.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

There's an enum with the same values (but slightly
different names except for NOT_SUPPORTED) that is
actually used, so remove the defines.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

This is the sort of thing gcc's LTO could do, but since
we don't have that yet we can also do it manually. The
advantage is reduced code, both source and binary, e.g.
on x86-64

   text	   data	    bss	    dec	    hex	filename
 442825	  56230	    776	 499831	  7a077	cfg80211.ko (before)
 441585	  56230	    776	 498591	  79b9f	cfg80211.ko (after)

a reduction of ~1k.

But in order to not complicate the code move only those
functions that are simple wrappers, not those that have
functionality of their own.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add back the channel width and extended capability data
to wiphy information if split information is supported.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Regardless of what header features they use, or if they align the IP
header or not, 802.11 packets from all drivers guarantee a 2-byte
alignment (and there's a debug WARN_ON in case they don't).

Annotate packet structs with __aligned(2) to allow the compiler to use
16-bit load/store operations on platforms with extremely inefficient
unaligned access (e.g. MIPS).

This reduces code size and improves performance on affected platforms
and causes no binary code change on others.
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Move the sequence number arithmetic code from mac80211 to
ieee80211.h so others can use it. Also rename the functions
from _seq to _sn, they operate on the sequence number, not
the sequence_control field.

Also move macros to convert the sequence control to/from
the sequence number value from various drivers.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Add back the previously removed TCP WoWLAN information,
but only if userspace is prepared to deal with large
wiphy capability data dumps.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

If userspace is updated to deal with large split wiphy
information dumps, add back the radar information that
could otherwise push the data over the limit of the
netlink dump messages.

Cc: Simon Wunderlich <simon.wunderlich@s2003.tu-chemnitz.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The per-wiphy information is getting large, to the point
where with more than the typical number of channels it's
too large and overflows, and userspace can't get any of
the information at all.

To address this (in a way that doesn't require making all
messages bigger) allow userspace to specify that it can
deal with wiphy information split across multiple parts
of the dump, and if it can split up the data. This also
splits up each channel separately so an arbitrary number
of channels can be supported.

Additionally, since GET_WIPHY has the same problem, add
support for filtering the wiphy dump and get information
for a single wiphy only, this allows userspace apps to
use dump in this case to retrieve all data from a single
device.

As userspace needs to know if all this this is supported,
add a global nl80211 feature set and include a bit for
this behaviour in it.

Cc: Dennis H Jensen <dennis.h.jensen@siemens.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The comment says something about __skb_push(), but that
isn't even called in the code any more. Looking at the
git history, that comment never even made sense when it
was still called, so just replace that part to note it
still works even when align isn't 0 or 2.
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

'rfkill_regulator_ops' is used only in this file. Hence make it static.
Silences the following warning:
net/rfkill/rfkill-regulator.c:54:19: warning:
symbol 'rfkill_regulator_ops' was not declared. Should it be static?
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

The station change API isn't being checked properly before
drivers are called, and as a result it is difficult to see
what should be allowed and what not.

In order to comprehensively check the API parameters parse
everything first, and then have the driver call a function
(cfg80211_check_station_change()) with the additionally
information about the kind of station that is being changed;
this allows the function to make better decisions than the
old code could.

While at it, also add a few checks, particularly in mesh
and clarify the TDLS station lifetime in documentation.

To be able to reduce a few checks, ignore any flag set bits
when the mask isn't set, they shouldn't be applied then.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Instead of copying the code, create a new function
to parse the station's WME information.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Parse the attributes first, and then disable the apply
flag if needed.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

All the pointers point right into the skb data and
not to anything that would be useful to change, so
make them const.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Make the ability to leave the plink_state unchanged not use a
magic -1 variable that isn't in the enum, but an explicit change
flag; reject invalid plink states or actions and move the needed
constants for plink actions to the right header file. Also
reject plink_state changes for non-mesh interfaces.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

There are a few things that would otherwise conflict.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Pull fbdev UAPI disintegration from David Howells:
 "You'll be glad to here that the end is nigh for the UAPI patches.
  Only the fbdev/framebuffer piece remains now that the SCSI stuff has
  gone in.

  Here are the UAPI disintegration bits for the fbdev drivers.  It
  appears that Florian hasn't had time to deal with my patch, but back
  in December he did say he didn't mind if I pushed it forward."

Yay.  No more uapi movement.  And hopefully no more big header file
cleanups coming up either, it just tends to be very painful.

* tag 'disintegrate-fbdev-20121220' of git://git.infradead.org/users/dhowells/linux-headers:
  UAPI: (Scripted) Disintegrate include/video

Merge tag 'stable/for-linus-3.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull Xen bug-fixes from Konrad Rzeszutek Wilk:
 - Update the Xen ACPI memory and CPU hotplug locking mechanism.
 - Fix PAT issues wherein various applications would not start
 - Fix handling of multiple MSI as AHCI now does it.
 - Fix ARM compile failures.

* tag 'stable/for-linus-3.9-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xenbus: fix compile failure on ARM with Xen enabled
  xen/pci: We don't do multiple MSI's.
  xen/pat: Disable PAT using pat_enabled value.
  xen/acpi: xen cpu hotplug minor updates
  xen/acpi: xen memory hotplug minor updates

Pull  more VFS bits from Al Viro:
 "Unfortunately, it looks like xattr series will have to wait until the
  next cycle ;-/

  This pile contains 9p cleanups and fixes (races in v9fs_fid_add()
  etc), fixup for nommu breakage in shmem.c, several cleanups and a bit
  more file_inode() work"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  constify path_get/path_put and fs_struct.c stuff
  fix nommu breakage in shmem.c
  cache the value of file_inode() in struct file
  9p: if v9fs_fid_lookup() gets to asking server, it'd better have hashed dentry
  9p: make sure ->lookup() adds fid to the right dentry
  9p: untangle ->lookup() a bit
  9p: double iput() in ->lookup() if d_materialise_unique() fails
  9p: v9fs_fid_add() can't fail now
  v9fs: get rid of v9fs_dentry
  9p: turn fid->dlist into hlist
  9p: don't bother with private lock in ->d_fsdata; dentry->d_lock will do just fine
  more file_inode() open-coded instances
  selinux: opened file can't have NULL or negative ->f_path.dentry

(In the meantime, the hlist traversal macros have changed, so this
required a semantic conflict fixup for the newly hlistified fid->dlist)