Re: [Qemu-devel] [PATCH 1/3] vfio-ccw: add capabilities chain

[Pierre Morel]

On 22/11/2018 17:54, Cornelia Huck wrote:
> Allow to extend the regions used by vfio-ccw. The first user will be
> handling of halt and clear subchannel.
>
> Signed-off-by: Cornelia Huck <address@hidden>
> ---
>   drivers/s390/cio/vfio_ccw_ops.c     | 182 ++++++++++++++++++++++++----
>   drivers/s390/cio/vfio_ccw_private.h |  38 ++++++
>   include/uapi/linux/vfio.h           |   1 +
>   3 files changed, 195 insertions(+), 26 deletions(-)

Halt and clear have no parameters (the sub-channel ID is obviously the 
one of the mediated device).

Isn't adding a new sub-region for the purpose of handling halt and clear 
superfluous?

What is the reason not to use simple ioctls ?

Regards,
Pierre

--
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany