sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

mlx5en: Fix TLS worker thread race.

Create a dedicated free state, in case the taskqueue worker is still pending,
to avoid re-activation of a freed send tag.

MFC after: 1 week
Sponsored by: NVIDIA Networking

mlx5en: Improve RX- and TX- TLS refcounting.

Use the send tag refcounting mechanism to refcount the RX- and TX- TLS
send tags. Then it is no longer needed to wait for refcounts to reach
zero when destroying RX- and TX- TLS send tags as a result of pending
data or WQE commands.

This also ensures that when TX-TLS and rate limiting is used at the same
time, the underlying SQ is not prematurely destroyed.

MFC after: 1 week
Sponsored by: NVIDIA Networking

mlx5en: Add missing TLS structure prototype.

MFC after: 1 week
Sponsored by: NVIDIA Networking

mlx5en: Remove unused hardware TLS field.

MFC after: 1 week
Sponsored by: NVIDIA Networking

Add a switch structure for send tags.

Move the type and function pointers for operations on existing send
tags (modify, query, next, free) out of 'struct ifnet' and into a new
'struct if_snd_tag_sw'. A pointer to this structure is added to the
generic part of send tags and is initialized by m_snd_tag_init()
(which now accepts a switch structure as a new argument in place of
the type).

Previously, device driver ifnet methods switched on the type to call
type-specific functions. Now, those type-specific functions are saved
in the switch structure and invoked directly. In addition, this more
gracefully permits multiple implementations of the same tag within a
driver. In particular, NIC TLS for future Chelsio adapters will use a
different implementation than the existing NIC TLS support for T6
adapters.

Reviewed by: gallatin, hselasky, kib (older version)
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D31572

Store the send tag type in the common send tag header.

Both cxgbe(4) and mlx5(4) wrapped the existing send tag header with
their own identical headers that stored the type that the
type-specific tag structures inherited from, so in practice it seems
drivers need this in the tag anyway. This permits removing these
extra header indirections (struct cxgbe_snd_tag and struct
mlx5e_snd_tag).

In addition, this permits driver-independent code to query the type of
a tag, e.g. to know what type of tag is being queried via
if_snd_query.

Reviewed by: gallatin, hselasky, np, kib
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D26689

Implement hardware TLS via send tags for mlx5en(4), which is supported by
ConnectX-6 DX.

Currently TLS v1.2 and v1.3 with AES 128/256 crypto over TCP/IP (v4
and v6) is supported.

A per PCI device UMA zone is used to manage the memory of the send
tags. To optimize performance some crypto contexts may be cached by
the UMA zone, until the UMA zone finishes the memory of the given send
tag.

An asynchronous task is used manage setup of the send tags towards the
firmware. Most importantly setting the AES 128/256 bit pre-shared keys
for the crypto context.

Updating the state of the AES crypto engine and encrypting data, is
all done in the fast path. Each send tag tracks the TCP sequence
number in order to detect non-contiguous blocks of data, which may
require a dump of prior unencrypted data, to restore the crypto state
prior to wire transmission.

Statistics counters have been added to count the amount of TLS data
transmitted in total, and the amount of TLS data which has been dumped
prior to transmission. When non-contiguous TCP sequence numbers are
detected, the software needs to dump the beginning of the current TLS
record up until the point of retransmission. All TLS counters utilize
the counter(9) API.

In order to enable hardware TLS offload the following sysctls must be set:
kern.ipc.mb_use_ext_pgs=1
kern.ipc.tls.ifnet.permitted=1
kern.ipc.tls.enable=1

Sponsored by: Mellanox Technologies