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&gt; wrote: > On Wed, 26 Jun 2019 11:58:06 +0200 > Cornelia Huck <cohuck(a)redhat.com&gt; wrote: > > > On Tue, 25 Jun 2019 16:52:51 -0600 > > Alex Williamson <alex.williamson(a)redhat.com&gt; 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