[Libguestfs] [PATCH nbdkit 0/9] nbd: Implement command= and socket-fd= parameters.

[Richard W.M. Jones]

On Thu, Jul 02, 2020 at 02:51:48PM +0300, Nir Soffer wrote:
> On Wed, Jul 1, 2020 at 10:17 AM Richard W.M. Jones <rjones at redhat.com> wrote:
> >
> > I fixed the deadlock - turned out to be an actual bug in the nbd
> > plugin (see patch 8).
> >
> > I changed the command syntax so it's now:
> >
> >   nbdkit nbd command=qemu arg=-f arg=qcow2 arg=/path/to/disk.qcow2
> >
> > Nir wrote:
> >
> > 18:08 < nsoffer> rwmjones: regarding the nbd proxy patches, did you have specific flow that help us?
> > 18:08 < nsoffer> rwmjones: or this is just a way to support qcow2 in the nbdkit pipeline?
> >
> > A bit of both - it's nice if nbdkit can "open" qcow2 files.
>
> Having libqcow2 would be even better, but since we don't have it
> this seems like a very useful feature.

I guess that "libqcow2" is unlikely to happen because the existing
code depends on internals of qemu (things like QMP, QOM and
coroutines), and hopefully no one would be foolhardy enough to write a
second qcow2 implementation.  Maybe that's changed since the
qemu-storage-daemon was implemented?

Anyway, this does seem like the best we can do in nbdkit.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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