Add kTLS TX crypto offload, layered on MPC (crypto add/delete
commands submitted over its TCE channel) and TX completion coalescing
(shared tx_bd_opaque encoding).
Adds kTLS session lifecycle management, a key-context ID allocator,
HWRM key-context alloc/free with partition-mode support, and the TX
submit path: in-order packets go out on the normal iflib path with
CSUM_SND_TAG set, while out-of-order or retransmitted TLS records get
a presync command plus a replayed copy of the record built from the
driver's own replay ring. Also adds kTLS/MPC completion-time counter
sysctls and the max_ktls_entries tunable.
Reviewed by: gallatin
MFC after: 2 weeks
Sponsored by: Broadcom Inc.
Differential Revision: https://reviews.freebsd.org/D58606
Sumit Saxena
70d389bede