Re: [Libguestfs] [PATCH 2/5] v2v/lib/util.ml: Get disk allocation from input

On 12/20/21 11:46, Richard W.M. Jones wrote: > On Mon, Dec 20, 2021 at 11:17:47AM +0100, Laszlo Ersek wrote: >> On 12/19/21 11:34, Richard W.M. Jones wrote: >>> On Sun, Dec 19, 2021 at 01:30:28AM +0200, Nir Soffer wrote: >>>> On Sun, Dec 19, 2021 at 12:40 AM Nir Soffer <nsoffer(a)redhat.com&gt; wrote: >>>>> >>>>> It can be fixed in another way, maybe skipping the check when using >>>>> rhv-upload because it cannot provide the needed info. >>>>> >>>>> I'm not sure why this check is needed - RHV already has everything >>>>> it needs at this point, and it does not care about disk allocation after >>>>> the disk was uploaded. If RHV needs any info about the disk, it can >>>>> get it from storage. >>>>> >>>>> Maybe you add stuff to the ovf that RHV does need? >>> >>> So looking at the commit (a2a4f7a09996) it seems as if it applies to >>> all OVF outputs (including -o rhv-upload), but I think we only >>> intended to add it to -o rhv output. >>> >>> Normally we'd do that by checking if ovf_flavor = RHVExportStorageDomain. >>> So I think a fix is to make the actual_size stuff dependent on that test. >>> >>>> I see that this code is not in rhel-9.0.0 branch, so this patch is not >>>> needed for https://bugzilla.redhat.com/2032324 >>> >>> It is in the latest rhel-9.0.0 branch. >>> >>>> Laszlo, can you explain why we need the number of allocated bytes >>>> after the disk was already converted to the target storage? >>>> >>>> Looking at the bug: >>>> https://bugzilla.redhat.com/2027598 >>>> >>>> This is a fix for the issue in the old rhv output, which is deprecated and >>>> should not be used in new code, and it is not compatible with rhv-upload >>>> which is the modern way to import into RHV. >>>> >>>> Also this cannot work for RHV now, so we need a way to disable >>>> this when importing to RHV. >>> >>> "RHV" here is confusing - I think you mean -o rhv-upload here? >>> (not -o rhv) >>> >>>> We can expose the block status in RHV plugin, but to use this we must >>>> call block status after the disk is converted, but before the output >>>> is finalized, since when you finalize RHV disconnect the disk from >>>> the host, and the RHV plugin cannot access it any more. >>>> >>>> The flow for rhv-upload should be: >>>> >>>> run nbdcopy >>>> query block status >>>> finalize output >>>> create ovf >>> >>> I suppose this won't be needed if we make the change above, but it was >>> Laszlo who investigated this issue in detail so let's see what he says. >> >> We have a common utility function (create_ovf) that no longer works for >> all call sites. >> >> (1) One way to fix it is to let each call site compute the list of disk >> sizes ("int64 option list"), pass that in to "create_ovf", and let >> "create_ovf" merge (combine) that list with the other lists it already >> merges. The callers that don't need this functionality can just pass in >> a list of "None"s. I outlined this in my previous email. >> >> (2) The other way to fix it is to restrict the logic inside >> "create_ovf", based on some other (simpler) parameter that tells apart >> the callers. If you tell me that "ovf_flavor = RHVExportStorageDomain" >> is a condition I can rely on, in "create_ovf", I'm happy to use that -- >> it's a lot simpler than the other option! Note that this would not >> generally restore the pre-modularization OVF output of virt-v2v, but >> maybe it does not matter for vdsm and rhv-upload? >> >> - "output_rhv.ml": passes in RHVExportStorageDomain as flavor >> >> - "output_rhv_upload.ml": passes OVirt as flavor >> >> - "output_vdsm.ml": well, this is tricky; this output plugin defaults to >> RHVExportStorageDomain, but can be flipped to OVirt via the "-oo >> vdsm-ovf-flavour" option! Does that match what we want to do in (2)? > > It's a bit of a hack isn't it, but it would solve the problem > for now. > > The fundamental problem here (again) is that OVF isn't a real format. > It's a collection of formats which share some common XML elements. In > this case it turns out we now have 3 formats: RHVExportStorageDomain, > OVirt, and (for -o vdsm) DataDomain (since -o vdsm writes directly > into the oVirt Data Domain). > > So ... I don't know ... How about a ?(need_actual_sizes = false) > optional param on create_ovf? Ugly but effective? Can I perhaps change the "dir:string" parameter of create_ovf to "dir:string option"?

Thanks! Laszlo