MFC r245243, r245274, r245276, r245434, r245441, r245448, r245467,
r245468, r245517, r245518, r245520, r245567, r245933, r245935, r245936,
r245937, r246093, r246385, r246575, r247062, r247122, r247289, r247291,
r247347, r247355, and r241733.

Note that TCP_OFFLOAD is not enabled in 9 yet and so some of these MFCs
don't really affect functionality.  But they do help future MFCs
(related to TCP_OFFLOAD or not) by minimizing diffs with the driver in
head.

r245243:
cxgbe(4): updates to the configuration file that controls how hardware
resources are partitioned.

- Reduce the number of virtual interfaces reserved for PF4.  This leaves
  spare room in the source MAC table and allows the driver to setup
  filters that rewrite the source MAC address.

- Reduce the number of filters and use the freed up space for the CLIP
  (Compressed Local IPv6 addresses) table.  This is a prerequisite for
  IPv6 TOE support which will follow separately in a series of commits.

r245274:
cxgbe(4): Add functions to help synchronize "slow" operations (those not
on the fast data path) and use them instead of frobbing the adapter lock
and busy flag directly.

Other changes made while reworking all slow operations:
- Wait for the reply to a filter request (add/delete).  This guarantees
  that the operation is complete by the time the ioctl returns.
- Tidy up the tid_info structure.
- Do not allow the tx queue size to be set to something that's not a
  power of 2.

r245276:
Overhaul the stid allocator so that it can be used for IPv6 servers
too.  The entry for an IPv6 server in the TCAM takes up the equivalent
of two ordinary stids and must be properly aligned too.

r245434:
cxgbe(4): Updates to the hardware L2 table management code.

- Add full support for IPv6 addresses.

- Read the size of the L2 table during attach.  Do not assume that PCIe
  physical function 4 of the card has all of the table to itself.

- Use FNV instead of Jenkins to hash L3 addresses and drop the private
  copy of jhash.h from the driver.

r245441:
cxgbe/tom: Miscellaneous updates for TOE+IPv6 support (more to follow).

- Teach find_best_mtu_idx() to deal with IPv6 endpoints.

- Install correct protosw in offloaded TCP/IPv6 sockets when DDP is
  enabled.

- Move set_tcp_ddp_ulp_mode to t4_tom.c so that t4_tom.h can be included
  without having to drag in t4_msg.h too.  This was bothering the iWARP
  driver for some reason.

r245448:
cxgbe/tom: Basic CLIP table management.

This is the Compressed Local IPv6 table on the chip.  To save space, the
chip uses an index into this table instead of a full IPv6 address in
some of its hardware data structures.

For now the driver fills this table with all the local IPv6 addresses
that it sees at the time the table is initialized.  I'll improve this
later so that the table is updated whenever new IPv6 addresses are
configured or existing ones deleted.

r245467:
cxgbe/tom: Add support for fully offloaded TCP/IPv6 connections (active open).

r245468:
cxgbe/tom: Add support for fully offloaded TCP/IPv6 connections (passive open).

r245517:
cxgbe: Fix the for_each_foo macros -- the last argument should not share
its name with any member of struct sge.

r245518:
cxgbe:  Do a more thorough job in the CLEAR_STATS ioctl.

r245520:
Allow "ivlan" (inner VLAN) to be used as an alias for "vlan" when
specifying match criteria.  "vlan" continues to be valid here, and it
continues to be valid when deleting, rewriting, inserting, or stacking
an 802.1q tag to a matching packet.

r245567:
cxgbe: Make the for_each macros safer to use by turning them
into a single statement each.

r245933:
cxgbe/tom: List IFCAP_TOE6 as supported now that all the required pieces
are in place.  You still have to enable it explicitly, after loading the
t4_tom KLD.

r245935:
Add a couple of missing error codes.  Treat CPL_ERR_KEEPALV_NEG_ADVICE as
negative advice and not a fatal error.

r245936:
Force the 404-BT card (4 x 1G) to use the "uwire" configuration file.

r245937:
Install an extra hold on the newly allocated synq entry so that it
cannot be freed while do_pass_accept_req is running.  This closes a race
where do_pass_establish on another CPU (the driver chose a different
queue for the new tid) expands the synq entry into a full PCB and then
releases the only hold on it, all while do_pass_accept_req is still
running.

r246093:
Provide a statistic to track the number of drops in each of the port's
txq's buf_ring.  The aggregate for all the queues of a port is already
provided in ifnet->if_snd.ifq_drops.

r246385:
Busy-wait when cold.

r246575:
Do not hold locks around hardware context reads.

r247062:
cxgbe(4): Assume that CSUM_TSO in the transmit path implies CSUM_IP and
CSUM_TCP too.  They are all set explicitly by the kernel usually.

r247122:
cxgbe(4): Add sysctls to extract debug information from the chip:

dev.t4nex.X.misc.cim_la         logic analyzer dump
dev.t4nex.X.misc.cim_qcfg       queue configuration
dev.t4nex.X.misc.cim_ibq_xxx    inbound queues
dev.t4nex.X.misc.cim_obq_xxx    outbound queues

r247289:
cxgbe(4): Update firmware to 1.8.4.0.

r247291:
cxgbe(4): Ask the card's firmware to pad up tiny CPLs by encapsulating
them in a firmware message if it is able to do so.  This works out
better for one of the FIFOs in the chip.

r247347:
cxgbe(4): Consider all the API versions of the interfaces exported by
the firmware (instead of just the main firmware version) when evaluating
firmware compatibility.  Document the new "hw.cxgbe.fw_install" knob
being introduced here.

This should fix kern/173584 too.  Setting hw.cxgbe.fw_install=2 will
mostly do what was requested in the PR but it's a bit more intelligent
in that it won't reinstall the same firmware repeatedly if the knob is
left set.

r247355:
cxgbe(4): Report unusual out of band errors from the firmware.

r241733 (by ed@):
Prefer __containerof() over __member2struct().

The former works better with qualifiers, but also properly type checks
the input pointer.