On Wed, Mar 04, 2020 at 15:01:07 +0100, Pavel Mores wrote: > On Wed, Mar 04, 2020 at 02:53:53PM +0100, Peter Krempa wrote: > > On Wed, Mar 04, 2020 at 14:41:09 +0100, Pavel Mores wrote: > > > On Wed, Mar 04, 2020 at 01:00:59PM +0100, Peter Krempa wrote: > > > > On Wed, Mar 04, 2020 at 11:12:37 +0100, Pavel Mores wrote: > > > > > A new command-line option --top was added to virsh's blockpull command. > > > > > Similar to how --base is handled, in presence of --top the operation is > > > > > implemented internally as a rebase. To that end, a corresponding new 'top' > > > > > parameter was added to virDomainBlockRebase(). > > > > > > > > > > Signed-off-by: Pavel Mores <pmores@xxxxxxxxxx> > > > > > --- > > > > > include/libvirt/libvirt-domain.h | 4 ++-- > > > > > src/libvirt-domain.c | 5 +++-- > > > > > tools/virsh-domain.c | 14 +++++++++++--- > > > > > 3 files changed, 16 insertions(+), 7 deletions(-) [...] > > This is obviously a lot of work, thus we need to decide whether adding > > an old-school API is worth it in the inerim. Are there any real users > > who would benefit from the new pull semantics? blockpull is around for a > > long time already, but it seems that commit is favoured. > > > > If there is no real demand though I'd probably prefer if we don't add > > any more block job APIs any more. > > I'm not aware of any real demand for this, however as I stated in the cover > letter I believe I need full blockpull to deal with the bug I'm actually > working on, which is full support for external snapshots in snapshot-delete. Deleting/reverting external snapshots needs to be done internally under the hood of virDomainRevertToSnapshot/virDomainSnapshotDelete so if you require use of the 'block-stream' command to an intermediate layer you don't actually need to expose it via virDomainBlockPull/Rebase to take advantage of it. For reversion of external snapshots you'll probably need a new API anyways as you'll need to be able to specify a new set of disk images to hold the writes.
