virt-v2v --in-place support
---------------------------

This was temporarily dropped when I modularized virt-v2v.  It is
intended to add this back, but with some changes.  I would like to get
rid of the idea of configuring the guest based on the "input" libvirt
XML, since that was and is a hack.  Instead we should have a new top
level "virt-v2v-in-place" program (compare v2v/v2v.ml) which would
parse new command line arguments and use the existing input and
convert helpers to modify a local disk image.  We might also consider
writing a new, simple input helper just for in-place which only works
for local files and does not use the COW filter.

virt-v2v -o disk|qemu -oo compressed
------------------------------------

This was temporarily dropped when I modularized virt-v2v.  It would
not be too difficult to add it back.  The following is the qemu-nbd
command required (to be run as the output helper) which creates a
compressed qcow2 disk image:

$ qemu-nbd --image-opts driver=compress,file.driver=qcow2,file.file.driver=file,file.file.filename=new.qcow2

virt-v2v -o rhv-upload
----------------------

* Set or disable the ticket timeout.  The default is going to be
  increased (from current 60 seconds), so maybe we won't have to
  set it.  See also:
  https://bugzilla.redhat.com/show_bug.cgi?id=1563278

* qcow2 cannot be supported yet because there is not yet any
  concept in imageio of read+write handles.
  https://bugzilla.redhat.com/show_bug.cgi?id=1563299

* preallocated cannot be supported yet because imageio doesn't
  know how to zero the image efficiently, instead it runs an
  fallocate process which writes to every block and that takes
  many minutes.

* Really check what insecure/rhv_cafile do and implement it correctly.

* Measure and resolve performance problems.

* Allocated image size is unknown for v2v uploads, but imageio needs
  to know it.  We pass initial_size == provisioned_size == virtual size.
  That can't be fixed from the v2v side.

* There are unresolved issues about how to clean up disks on failure.

virt-v2v -o openstack
---------------------

Use the metadata service to find the -oo server-id setting.  It would
no longer need to be specified on the command line.  Note there are
two variations of metadata service in OpenStack, either the config
disk or link-local network address.  We would need to support both, or
the possibility that there is no metadata service.
