[PATCH 0/5] Drop vhost async (DMA-accelerated) datapath

[David Marchand]

The integration of this feature in OVS has been postponed following
feedback how the current API forced the complexity on the application
side. There is no contributor working on making those changes.

The feature has no other identified opensource consumer.

On the other hand, this feature has been left unattended for some years
now while the "normal" datapath is actively maintained.
It is highly likely the async datapath code, which never underwent a
stabilisation phase, is riddled with bugs.

Given the craziness around finding security bugs with AI,
and since the vhost library is a good target, I propose to drop
this feature and reduce the library attack surface.

There is one complication with the vhost_crypto and some external
applications that seemed to rely on the async flag to track and populate
guest pages, so a new flag replacing async is added by this series.


-- 
David Marchand

Changes since RFC:
- maintained guest pages population in a new flag (vhost_crypto/SPDK),
- removed remaining helpers which had sync_ in their names,


David Marchand (5):
  vhost: decouple guest pages population from async datapath
  examples/vhost: stop using async datapath
  vhost: drop async datapath
  vhost: rename packed layout helpers for batches
  vhost: simplify some descriptor handling

 doc/guides/prog_guide/vhost_lib.rst    |  152 +-
 doc/guides/rel_notes/release_26_11.rst |   20 +
 examples/vhost/Makefile                |    2 -
 examples/vhost/main.c                  |  436 +--
 examples/vhost/main.h                  |   21 +-
 examples/vhost/meson.build             |    2 -
 examples/vhost_crypto/Makefile         |    1 -
 examples/vhost_crypto/main.c           |    2 +-
 examples/vhost_crypto/meson.build      |    1 -
 lib/vhost/meson.build                  |    3 +-
 lib/vhost/rte_vhost.h                  |    2 +-
 lib/vhost/rte_vhost_async.h            |  293 ---
 lib/vhost/socket.c                     |   20 +-
 lib/vhost/vhost.c                      |  434 ---
 lib/vhost/vhost.h                      |  116 +-
 lib/vhost/vhost_user.c                 |  115 +-
 lib/vhost/virtio_net.c                 | 3343 +++++-------------------
 17 files changed, 736 insertions(+), 4227 deletions(-)
 delete mode 100644 lib/vhost/rte_vhost_async.h

-- 
2.54.0