Re: [PATCH v2 0/7] vfio-ccw parent rework

[Alex Williamson <alex.williamson@redhat.com>]

On Wed,  2 Nov 2022 16:01:45 +0100
Eric Farman <farman@linux.ibm.com> wrote:

> Hi all,
> 
> Here is an update to the vfio-ccw lifecycle changes that have been discussed
> in various forms over the past year [1][2] or so, and which I dusted off
> recently.
> 
> Patches 1-5 rework the behavior of the vfio-ccw driver's private struct.
> In summary, the mdev pieces are split out of vfio_ccw_private and into a
> new vfio_ccw_parent struct that will continue to follow today's lifecycle.
> The remainder (bulk) of the private struct moves to follow the mdev
> probe/remove pair. There's opportunity for further separation of the
> things in the private struct, which would simplify some of the vfio-ccw
> code, but it got too hairy as I started that. Once vfio-ccw is no longer
> considered unique, those cleanups can happen at our leisure. 
> 
> Patch 6 removes the trickery where vfio-ccw uses vfio_init_device instead of
> vfio_alloc_device, and thus removes vfio_init_device from the outside world.
> 
> Patch 7 removes vfio_free_device from vfio-ccw and the other drivers (hello,
> CC list!), letting it be handled by vfio_device_release directly.

Looks like another spin is pending, but the vfio core and collateral
changes in 6 and 7 look good to me.  Would this go in through the vfio
or s390 tree?  I'd be happy to merge or provide a branch, depending on
the route.

For 6 & 7:
Acked-by: Alex Williamson <alex.williamson@redhat.com>

Thanks,
Alex


> Looking forward to the feedback.
> 
> Thanks,
> Eric
> 
> [1] https://lore.kernel.org/kvm/0-v3-57c1502c62fd+2190-ccw_mdev_jgg@nvidia.com/
> [2] https://lore.kernel.org/kvm/20220602171948.2790690-1-farman@linux.ibm.com/
> 
> v1->v2:
>  - Rebase to 6.1-rc3
>  - Patch 1:
>    [EF] s/device_initialize/device_register/ and associated adjustments
>    [MR] Add WARN_ON(!private) in vfio_ccw_sch_quiesce()
>    [MR] Move struct vfio_ccw_parent to _private.h, instead of standalone file
>  - Patch 2:
>    [MR] Added r-b (Thank you!)
>  - Patch 3:
>    [MR] Update commit message to point to introduction of private->release_comp
>    [MR] Replace the remnants of vfio_ccw_alloc_private with a straight kzalloc
>    [MR] Added r-b (Thank you!)
>  - Patch 5:
>    [KT] Added r-b (Thank you!)
>  - Patch 6:
>    [JG] Make vfio_init_device static
>    [KT] Added r-b (Thank you!)
>  - Patch 7:
>    [JG, KT] Added r-b (Thank you!)
> v1: https://lore.kernel.org/kvm/20221019162135.798901-1-farman@linux.ibm.com/
> 
> Eric Farman (7):
>   vfio/ccw: create a parent struct
>   vfio/ccw: remove private->sch
>   vfio/ccw: move private initialization to callback
>   vfio/ccw: move private to mdev lifecycle
>   vfio/ccw: remove release completion
>   vfio/ccw: replace vfio_init_device with _alloc_
>   vfio: Remove vfio_free_device
> 
>  drivers/gpu/drm/i915/gvt/kvmgt.c      |   1 -
>  drivers/s390/cio/vfio_ccw_chp.c       |   5 +-
>  drivers/s390/cio/vfio_ccw_drv.c       | 174 +++++++++++---------------
>  drivers/s390/cio/vfio_ccw_fsm.c       |  27 ++--
>  drivers/s390/cio/vfio_ccw_ops.c       | 107 +++++++++++-----
>  drivers/s390/cio/vfio_ccw_private.h   |  37 ++++--
>  drivers/s390/crypto/vfio_ap_ops.c     |   6 -
>  drivers/vfio/fsl-mc/vfio_fsl_mc.c     |   1 -
>  drivers/vfio/pci/vfio_pci_core.c      |   1 -
>  drivers/vfio/platform/vfio_amba.c     |   1 -
>  drivers/vfio/platform/vfio_platform.c |   1 -
>  drivers/vfio/vfio_main.c              |  32 ++---
>  include/linux/vfio.h                  |   3 -
>  samples/vfio-mdev/mbochs.c            |   1 -
>  samples/vfio-mdev/mdpy.c              |   1 -
>  samples/vfio-mdev/mtty.c              |   1 -
>  16 files changed, 197 insertions(+), 202 deletions(-)
>