- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Rework the tx credit mechanism between the cxgbe/tom driver
and the card. This helps smooth out some burstiness in the
exchange.

Approved by: re (glebius)

Change t4_list_lock and t4_uld_list_lock from mutexes to sx'es.

- tom_uninit had to be reworked not to hold the adapter lock (a mutex)
around t4_deactivate_uld, which acquires the uld_list_lock.
- the ifc_match for the interface cloner that creates the tracer ifnet
had to be reworked as the kernel calls ifc_match with the global
if_cloners_mtx held.

Pay attention to TCP_NODELAY when it's set/unset after the connection
is established.

MFC after: 1 day

- Read all TP parameters in one place.
- Read the filter mode, calculate various shifts, and use them
properly during active open (in select_ntuple).

MFC after: 1 day

cxgbe/tom: Update the CLIP table on the chip when there are changes
to the list of IPv6 addresses on the system. The table is used for
TOE+IPv6 only.

cxgbe(4): Add support for Chelsio's Terminator 5 (aka T5) ASIC. This
includes support for the NIC and TOE features of the 40G, 10G, and
1G/100M cards based on the T5.

The ASIC is mostly backward compatible with the Terminator 4 so cxgbe(4)
has been updated instead of writing a brand new driver. T5 cards will
show up as cxl (short for cxlgb) ports attached to the t5nex bus driver.

Sponsored by: Chelsio

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

MFC after: 3 days

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.

MFC after: 1 week

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.

MFC after: 1 week

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.

MFC after: 1 week

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.

MFC after: 1 week

Revert previous commit...

Pointyhat to: kevlo (myself)

Prefer NULL over 0 for pointers

Minor cleanup: use bitwise ops instead of pointless wrappers around
setbit/clrbit.

Support for TCP DDP (Direct Data Placement) in the T4 TOE module.

Basically, this is automatic rx zero copy when feasible. TCP payload is
DMA'd directly into the userspace buffer described by the uio submitted
in soreceive by an application.

- Works with sockets that are being handled by the TCP offload engine
of a T4 chip (you need t4_tom.ko module loaded after cxgbe, and an
"ifconfig +toe" on the cxgbe interface).
- Does not require any modification to the application.
- Not enabled by default. Use hw.t4nex.<X>.toe.ddp="1" to enable it.

- Updated TOE support in the kernel.

- Stateful TCP offload drivers for Terminator 3 and 4 (T3 and T4) ASICs.
These are available as t3_tom and t4_tom modules that augment cxgb(4)
and cxgbe(4) respectively. The cxgb/cxgbe drivers continue to work as
usual with or without these extra features.

- iWARP driver for Terminator 3 ASIC (kernel verbs). T4 iWARP in the
works and will follow soon.

Build-tested with make universe.

30s overview
============
What interfaces support TCP offload? Look for TOE4 and/or TOE6 in the
capabilities of an interface:
# ifconfig -m | grep TOE

Enable/disable TCP offload on an interface (just like any other ifnet
capability):
# ifconfig cxgbe0 toe
# ifconfig cxgbe0 -toe

Which connections are offloaded? Look for toe4 and/or toe6 in the
output of netstat and sockstat:
# netstat -np tcp | grep toe
# sockstat -46c | grep toe

Reviewed by: bz, gnn
Sponsored by: Chelsio communications.
MFC after: ~3 months (after 9.1, and after ensuring MFC is feasible)