qemu allows and in some cases uses protocol driver names ('file',
'host_device', 'nbd', ...) in the 'backing file format' field of a qcow
to denote a image where the dummy 'raw' driver was not used on top.
Adapt our backing store parser for such cases. The examples added in
previous patch show the difference in behaviour.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
QEMU allows and in cases where you omit the not-strictly-needed 'raw'
driver on top of raw images automatically uses the protocol name inside
of the 'backing file format' field of the qcow2 image.
Libvirt expects only format names in that field.
Add example images showing this scenario, which will be fixed later.
The qcow2 image files in this commit were formatted as:
qemu-img create -f qcow2 -F nbd -b nbd+tcp://example.org:6000/blah -u qcow2-protocol-backing-nbd.qcow2 10M
and
qemu-img create -f qcow2 -F file -b raw qcow2-protocol-backing-file.qcow2
thus using 'nbd' and 'file' as backing format respectively.
(note that '-b raw' refers to the file in the example image folder)
To satisfy the test, note that the NBD image is also rejected as we
can't probe it, thus such configuration would not work.
Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>
