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>

Since the PNs of all the tx keys are now tracked in the public
part of the key struct (with atomic counter), we no longer
need these functions.

dvm and vt665{5,6} are currently the only users of these functions,
so update them accordingly.

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>

Some drivers/devices might want to set the IVs by
themselves (and still let mac80211 generate MMIC).

Specifically, this is needed when the device does
offloading at certain times, and the driver has
to make sure that the IVs of new tx frames (from
the host) are synchronized with IVs that were
potentially used during the offloading.

Similarly to CCMP, move the TX IVs of TKIP keys to the
public part of the key struct, and export a function
to add the IV right into the crypto header.

The public tx_pn field is defined as atomic64, so define
TKIP_PN_TO_IV16/32 helper macros to convert it to iv16/32
when needed.

Since the iv32 used for the p1k cache is taken
directly from the frame, we can safely remove
iv16/32 from being protected by tkip.txlock.

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>

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>

This struct member is only assigned, never used otherwise;
remove it.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

Conflicts:
	drivers/net/ethernet/mellanox/mlx4/main.c
	net/packet/af_packet.c

Both conflicts were cases of simple overlapping changes.

Signed-off-by: David S. Miller <davem@davemloft.net>

Unfortunately, Michal's change to fix AP_VLAN crypto tailroom
caused a locking issue that was reported by lockdep, but only
in a few cases - the issue was a classic ABBA deadlock caused
by taking the mtx after the key_mtx, where normally they're
taken the other way around.

As the key mutex protects the field in question (I'm adding a
few annotations to make that clear) only the iteration needs
to be protected, but we can also iterate the interface list
with just RCU protection while holding the key mutex.

Fixes: f9dca80b98ca ("mac80211: fix AP_VLAN crypto tailroom calculation")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

Merge back net-next to get wireless driver changes (from Kalle)
to be able to create the API change across all trees properly.

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