On Wed, Nov 09, 2022 at 11:30:55PM +0100, David Disseldorp via samba-technical wrote: > I think it's doable too :-). As indicated in my other mail, I think > FICLONERANGE will need to be used for FSCTL_DUP_EXTENTS_TO_FILE instead > of copy_file_range(). > I'm not sure how to best handle FILE_SUPPORTS_BLOCK_REFCOUNTING - > ideally we'd set it for Btrfs and XFS(reflink=1) backed shares only. > Another option might be to advertise FILE_SUPPORTS_BLOCK_REFCOUNTING and > then propagate errors up to the client if FICLONERANGE fails for > FSCTL_DUP_EXTENTS_TO_FILE. Client copy fallback would work, but the > extra request overhead would be ugly. We could probably add a bit to struct statx if that is helpful for samba.
