MFC r333153, r333394, r333442, r333472, r333620, r334058, r334447,
r334452, and r335684. These revisions added hashfilters, NAT offload,
and SMAC/DMAC swapping filters to cxgbe.

r333153:
cxgbe(4): Move all TCAM filter code into a separate file.

Sponsored by: Chelsio Communications

r333394:
cxgbe(4): Add support for hash filters.

These filters reside in the card's memory instead of its TCAM and can be
configured via a new "hashfilter" subcommand in cxgbetool. Hash and
normal TCAM filters can be used together. The hardware does an
exact-match of packet fields for hash filters, unlike the masked match
performed for TCAM filters. Any T5/T6 card with memory can support at
least half a million hash filters. The sample config file with the
driver configures 512K of these, it is possible to double this to 1
million+ in some cases.

The chip does an exact-match of fields of incoming datagrams with hash
filters and performs the action configured for the filter if it matches.
The fields to match are specified in a "filter mask" in the firmware
config file. The filter mask always includes the 5-tuple (sip, dip,
sport, dport, ipproto). It can, optionally, also include any subset of
the filter mode (see filterMode and filterMask in the firmware config
file).

For example:
filterMode = fragmentation, mpshittype, protocol, vlan, port, fcoe
filterMask = protocol, port, vlan

Exact values of the 5-tuple, the physical port, and VLAN tag would have
to be provided while setting up a hash filter with the chip
configuration above.

Hash filters support all actions supported by TCAM filters. A packet
that hits a hash filter can be dropped, let through (with optional
steering to a specific queue or RSS region), switched out of another
port (with optional L2 rewrite of DMAC, SMAC, VLAN tag), or get NAT'ed.
(Support for some of these will show up in the driver in a follow-up
commit very shortly).

Sponsored by: Chelsio Communications

r333442:
cxgbe(4): Determine whether the firmware supports the FILTER2 work
request, which can be used to configure hardware NAT and swapmac.

All firmwares released after Jan 2017 support this work request.

Sponsored by: Chelsio Communications

r333472:
cxgbe(4): Add fields to support configuration of hardware NAT and
swapmac (SMAC/DMAC switcheroo) from userspace.

Sponsored by: Chelsio Communications

r333620:
cxgbe(4): Filtering related features and fixes.

• Driver support for hardware NAT.
• Driver support for swapmac action.
• Validate a request to create a hashfilter against the filter mask.
• Add a hashfilter config file for T5.

Sponsored by: Chelsio Communications

r334058:
cxgbe(4): Only valid filters are expected to have a valid tid.

r334447:
cxgbe(4): Add code to deal with the chip's source MAC table (aka SMT).

Submitted by: Krishnamraju Eraparaju @ Chelsio
Sponsored by: Chelsio Communications

r334452:
cxgbe(4): Add support for SMAC-rewriting filters.

Submitted by: Krishnamraju Eraparaju @ Chelsio
Sponsored by: Chelsio Communications

r335684:
cxgbe(4): Do not leak the filters in the hashfilter table on module
unload.

Sponsored by: Chelsio Communications

Relnotes: Yes