Rewrite abs() so that its return type does not depend on the
architecture and no unexpected type conversion happen inside of it.  The
only conversion is from unsigned to signed type.  char is left as a
return type but treated as a signed type regradless of it's actual
signedness.

With the old version, int arguments were promoted to long and depending
on architecture a long argument might result in s64 or long return type
(which may or may not be the same).

This came after some back and forth with Nicolas.  The current macro has
different return type (for the same input type) depending on
architecture which might be midly iritating.

An alternative version would promote to int like so:

	#define abs(x)	__abs_choose_expr(x, long long,			\
			__abs_choose_expr(x, long,			\
			__builtin_choose_expr(				\
				sizeof(x) <= sizeof(int),		\
				({ int __x = (x); __x<0?-__x:__x; }),	\
				((void)0))))

I have no preference but imagine Linus might.  :] Nicolas argument against
is that promoting to int causes iconsistent behaviour:

	int main(void) {
		unsigned short a = 0, b = 1, c = a - b;
		unsigned short d = abs(a - b);
		unsigned short e = abs(c);
		printf("%u %u\n", d, e);  // prints: 1 65535
	}

Then again, no sane person expects consistent behaviour from C integer
arithmetic.  ;)

Note:

  __builtin_types_compatible_p(unsigned char, char) is always false, and
  __builtin_types_compatible_p(signed char, char) is also always false.

Signed-off-by: Michal Nazarewicz <mina86@mina86.com>
Reviewed-by: Nicolas Pitre <nico@linaro.org>
Cc: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Cc: Wey-Yi Guy <wey-yi.w.guy@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* bug fixes and improvements for firmware debug system (Golan and myself)
* fixes for D0i3 (Eliad)
* prevent muliple stations with the same MAC address
* advertise support for Rx A-MSDU in A-MPDU
* scan related fixes
* support -20.ucode
* fix WoWLAN for iwldvm
* preparations towards multiple Rx queues
* platform power improvements for GO mode when no clients are associated

8000 device family has a new debug engine that needs to be
configured differently than 7000's.
The debug engine's DMA works in chunks of memory and the
size of the buffer really means the start of the last
chunk. Since one chunk is 256-byte long, we should
configure the device to write to buffer_size - 256.
This fixes a situation were the device would write to
memory it is not allowed to access.

CC: <stable@vger.kernel.org> [4.1+]
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

When iwl_mvm_fw_error_dump fails, it needs to clear the
state in mvm, which includes:
	* clear IWL_MVM_STATUS_DUMPING_FW_LOG
	* set mvm->fw_dump_trig to NULL
	* free the description

While at it, remove a NULL check in
iwl_mvm_free_fw_dump_desc since kfree is NULL safe.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

The debug functions of fw-dbg.c don't really need to modify
the trigger and the description they receive as a parameter.
Constify the pointers.

Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

This notification will be extended with extra data, so just
check that it has a minimum length, not the exact length;
we might later add handling for the extra fields added and
have more code to handle both versions.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

gtkdata->mvm wasn't set in iwl_mvm_d0i3_update_keys,
resulting in kernel panic in some flows (when mvm
is actually used...)

Fixes: a3f7ba5c8825 ("iwlwifi: update key params on d0i3 entrance/exit")
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

As we're working on multi-queue RX, we want to parallelise checking
the PN in order to avoid having to serialise the RX processing.

It may seem that doing parallel PN checking is insecure, but it turns
out to be OK because queue assignment is done based on the data in the
frame (IP/TCP) and thus cannot be manipulated by an attacker, since
the data is encrypted and must first have been decrypted successfully.

There are some corner cases, in particular when the peer starts using
fragmentation which redirects the packet to the default queue. However
this redirection is remembered (for the STA, per TID) and thus cannot
be exploited by an attacker either.

Leave checking on the default queue (queue 0) to mac80211, since we
get fragmented packets there and those are subject to stricter checks
during reassembly.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

The commit below called iwl_mvm_mac_ctxt_changed() to handle
a case that the vif is a P2P GO.
However iwl_mvm_mac_ctxt_cmd_go() ignores the number of
associated stations and asks the FW to pass beacons anyways.

Fix this by checking ap_assoc_sta_count parameter, in iwl_mvm_mac_ctxt_cmd_go()
as well, and ask the FW to pass beacons only when there's
at least one associated station.

Signed-off-by: Ayala Beker <ayala.beker@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>

As the device (and parts of the driver) cannot deal with having the
same MAC address for two stations (on two virtual interfaces), add
some explicit code to prevent this case.

Note that in practice this cannot happen since the device doesn't
support operating with two AP/GO interfaces at the same time either,
and other scenarios for this are, while not impossible, not going to
happen in practice.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>