Re: [libvirt] [RFC v3] external (pull) backup API
On 05/17/2018 05:43 PM, Eric Blake wrote:
Here's my updated counterproposal for a backup API.
In comparison to v2 posted by Nikolay:
https://www.redhat.com/archives/libvir-list/2018-April/msg00115.html
- changed terminology a bit: Nikolay's "BlockSnapshot" is now called a
"Checkpoint", and "BlockExportStart/Stop" is now
"BackupBegin/End"
- flesh out more API descriptions
- better documentation of proposed XML, for both checkpoints and backup
Barring any major issues turned up during review, I've already starting
to code this into libvirt with a goal of getting an implementation ready
for review this month.
// Many additional functions copying heavily from
virDomainSnapshot*:
virDomainCheckpointList(virDomainPtr domain,
virDomainCheckpointPtr **checkpoints,
unsigned int flags);
int
virDomainCheckpointListChildren(virDomainCheckpointPtr checkpoint,
virDomainCheckpointPtr **children,
unsigned int flags);
Notably, none of the older racy list functions, like
virDomainSnapshotNum, virDomainSnapshotNumChildren, or
virDomainSnapshotListChildrenNames; also, for now, there is no revert
support like virDomainSnapshotRevert.
I'm finding it easier to understand if I name these:
virDomainListCheckpoints() (find checkpoints relative to a domain)
virDomainCheckpointListChildren() (find children relative to a checkpoint)
The counterpart Snapshot API used virDomainListAllSnapshots(); the term
'All' was present because it was added after the initial racy
virDomainSnapshotNum(), but as we are avoiding the racy API here we can
skip it from the beginning.
--
Eric Blake, Principal Software Engineer
Red Hat, Inc. +1-919-301-3266
Virtualization: qemu.org | libvirt.org