[libvirt] RFC: VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA is not functional?

[Han Han]

Hello,
I found snapshot APIs(like virDomainSnapshotNum) invoked with
VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA will return 0 even there are internal
no-metadata snapshots in the domain.

Then I find the reason is in virDomainSnapshotObjListGetNames():
   937     /* If this common code is being used, we assume that all
snapshots
   938     ┆* have metadata, and thus can handle METADATA up front as
an
   939     ┆* all-or-none filter.  XXX This might not always be true, if
we
   940     ┆* add the ability to track qcow2 internal snapshots without
the
   941     ┆* use of metadata.
*/
   942     if ((data.flags & VIR_DOMAIN_SNAPSHOT_FILTERS_METADATA)
==
   943     ┆
VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA)
   944     ┆   return 0;

So currently, with VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA, no snapshot will
be returned.

I checked the commit. It is really old(6478ec1673a    Eric Blake
2012-08-13 18:09:12 -0600) . I guess it was initially designed for the
function to list internal snapshots without metadata.

However, now internal snapshot seems lower prioritized than external
snapshot.
Do we have plan to design this function? Since the APIs invoked with this
flag don't return the **right** result, if the function for
VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA will not be designed, how will we deal
with the flag? Remove it from code OR update the docs to mark it
unsupported?


-- 
Best regards,
-----------------------------------
Han Han
Quality Engineer
Redhat.

Email: hhan at redhat.com
Phone: +861065339333
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/libvir-list/attachments/20181102/d60f71af/attachment-0001.htm>