Re: [Qemu-devel] Design of the blobstore

[Michael S. Tsirkin]

On Wed, Sep 14, 2011 at 01:49:50PM -0400, Stefan Berger wrote:
> On 09/14/2011 01:40 PM, Michael S. Tsirkin wrote:
> >On Wed, Sep 14, 2011 at 01:05:44PM -0400, Stefan Berger wrote:
> >>qemu ... \
> >>     -blobstore name=my-blobstore,drive=tpm-bs,showsize \
> >>     -drive if=none,id=tpm-bs \
> >>     -tpmdev libtpms,blobstore=my-blobstore,id=tpm0 \
> >>     -device tpm-tis,tpmdev=tpm0
> >>
> >>which would result in QEMU printing to stdout:
> >>
> >>Blobstore tpm-store on drive with ID tpm-bs requires 83kb.
> >So you envision tools parsing this freetext then?
> >Seems like a step back, we are trying to move to QMP ...
> I extended it first for the way I typically interact with QEMU. I do
> not use the monitor much.

It will work even better if there's a tool to do the job instead of cut
and pasting stuff, won't it? And for that, we need monitor commands.

> >
> >So with above, the raw case which we don't expect to be used often
> >is easy to use, but qcow which we expect to be the main case
> >is close to imposible, involving manual cut and paste
> >of image size.
> >
> >Formatting images seems a rare enough occasion,
> >that I think only using monitor command for that
> >would be a better idea than a ton of new command
> >line options. On top of that, let's write a
> >script that run qemu, queries image size,
> >creates a qcow2 file, run qemu again to format,
> >all this using QMP.
> Creates the qcow2 using 'qemu-img' I suppose.
> 
>    Stefan

Sure.

> >WRT 'format and run in one go' I strongly disagree with it.
> >It's just too easy to shoot oneself in the foot.