Am 09.08.2019 um 18:13 hat Max Reitz geschrieben: > If the driver does not implement bdrv_get_allocated_file_size(), we > should fall back to cumulating the allocated size of all non-COW > children instead of just bs->file. > > Suggested-by: Vladimir Sementsov-Ogievskiy <vsement...@virtuozzo.com> > Signed-off-by: Max Reitz <mre...@redhat.com>
This smells like an overgeneralisation, but if we want to count all vmdk extents, the qcow2 external data file, etc. it's an improvement anyway. A driver that has a child that should not be counted must just remember to implement the callback. Let me think of an example... How about quorum, for a change? :-) Or the second blkverify child. Or eventually the block job filter nodes. Ehm... Maybe I should just take back what I said first. It almost feels like it would be better if qcow2 and vmdk explicitly used a handler that counts all children (could still be a generic one in block.c) rather than having to remember to disable the functionality everywhere where we don't want to have it. And please adjust the comment for bdrv_get_allocated_file_size(), it only talks about a single file as if trees didn't exist. Actually, it doesn't even seem so easy to define. Maybe primary node + storage nodes? Then vmdk needs to expose its extents as storage nodes (plural!), but in the long run that might be needed anyway. Kevin
