Re: [libvirt] mdevctl: A shoestring mediated device management and persistence utility
On Wed, 26 Jun 2019 08:37:20 -0600
Alex Williamson <alex.williamson(a)redhat.com> wrote:
On Wed, 26 Jun 2019 11:58:06 +0200
Cornelia Huck <cohuck(a)redhat.com> wrote:
> On Tue, 25 Jun 2019 16:52:51 -0600
> Alex Williamson <alex.williamson(a)redhat.com> wrote:
>
> > Hi,
> >
> > Based on the discussions we've had, I've rewritten the bulk of
> > mdevctl. I think it largely does everything we want now, modulo
> > devices that will need some sort of 1:N values per key for
> > configuration in the config file versus the 1:1 key:value setup we
> > currently have (so don't consider the format final just yet).
>
> We might want to factor out that config format handling while we're
> trying to finalize it.
>
> cc:ing Matt for his awareness. I'm currently not quite sure how to
> handle those vfio-ap "write several values to an attribute one at a
> time" requirements. Maybe 1:N key:value is the way to go; maybe we
> need/want JSON or something like that.
Maybe we should just do JSON for future flexibility. I assume there
are lots of helpers that should make it easy even from a bash script.
I'll look at that next.
Done. Throw away any old mdev config files, we use JSON now. The per
mdev config now looks like this:
{
"mdev_type": "i915-GVTg_V4_8",
"start": "auto"
}
My expectation, and what I've already pre-enabled support in set_key
and get_key functions, is that we'd use arrays for values, so we might
have:
"new_key": ["value1", "value2"]
set_key will automatically convert a comma separated list of values
into such an array, so I'm thinking this would be specified by the user
as:
# mdevctl modify -u UUID --key=new_key --value=value1,value2
We should think about whether ordering is important and maybe
incorporate that into key naming conventions or come up with some
syntax for specifying startup blocks. Thanks,
Alex