Re: [Qemu-devel] [RFC PATCH 01/14] docs: block replication's description

[Fam Zheng]

On Fri, 02/27 10:27, Wen Congyang wrote:
> > 1. nbd-target0 is writable here, without the drive-backup, hidden0 could be
> > corrupted by writings to it. So there need to be a new convention and
> > invariance to follow.
> 
> Hmm, I understand while the hidden-disk should be opened automatically now.
> If we use backing reference, I think we should open a hindden-disk, and set
> drive backup automatically. Block any conflict operations(commit, change, 
> eject?)

This might be a good idea.

> 
> > 
> > 2. in qmp, block-commit hidden0 to nbd-target0 or it's backing file, will
> > corrupt data (from nbd-target0's perspective).
> > 
> > 3. unclear implications of "change" and "eject" when there is backing
> > reference.
> > 
> > 4. can a drive be backing referenced by more than one other drives?
> 
> We can forbid it first.
> 

Yes, probably with a new op blocker type.

Fam