[PATCH hci-8.1 v3 0/4] vhost-blk: switch from VHOST_SET_NWORKERS to the mainstream worker ioctls

[Alexander Ivanov <alexander.ivanov@virtuozzo.com>]

The kernel drops our VHOST_SET_NWORKERS ioctl in favour of the
mainstream VHOST_NEW_WORKER/VHOST_ATTACH_VRING_WORKER, which vhost-blk
now supports.

Patch 1 wraps VHOST_SET_FORK_FROM_OWNER in a vhost backend op. Patch 2
refuses num-queues above VHOST_BLK_MAX_QUEUES at realize. Patch 3 makes
vhost-blk create its num-threads workers with the mainstream ioctls,
keeping the same worker layout, and fall back to a single thread on a
kernel without them. Patch 4 drops VHOST_SET_NWORKERS from
linux-headers.

v3:
- new patch 1: call VHOST_SET_FORK_FROM_OWNER, VHOST_NEW_WORKER and
  VHOST_ATTACH_VRING_WORKER through vhost_ops instead of raw ioctls
- new patch 2: refuse num-queues above VHOST_BLK_MAX_QUEUES at realize
  instead of clamping num-threads in patch 3
- patch 3: create each worker right before attaching its first vq

v2:
- patch 1: clamp num-threads to VHOST_BLK_MAX_QUEUES
- patch 1: note in the commit message that our kernel, unlike
  mainline, defaults to kthreads

https://virtuozzo.atlassian.net/browse/VSTOR-107537

Alexander Ivanov (4):
  vhost-backend: add vhost_set_fork_from_owner op
  vhost-blk: reject num-queues above VHOST_BLK_MAX_QUEUES
  vhost-blk: create kernel threads with the mainstream worker ioctls
  linux-headers: drop VHOST_SET_NWORKERS

 hw/block/vhost-blk.c              | 105 +++++++++++++++++++++++++-----
 hw/virtio/vhost-backend.c         |   7 ++
 include/hw/virtio/vhost-backend.h |   3 +
 linux-headers/linux/vhost.h       |   9 ---
 4 files changed, 99 insertions(+), 25 deletions(-)

-- 
2.53.0