On Wed, Oct 25, 2023 at 07:04:45PM +0200, Jan Kara wrote: > Well, this is the discussion how btrfs should be presenting its subvolumes > to VFS / userspace, isn't it? Yes. Which we've pressured to resolve forever, but it's been ignored. > I never dived into that too closely but as > far as I remember it was discussed to death without finding an acceptable > (to all parties) solution? I guess having a different fsid per subvolume > makes sense (and we can't change that given it is like that forever even if > we wanted). Having different subvolumes share one superblock is more > disputable but there were reasons for that as well. So I'm not sure how you > imagine to resolve this... We need to solve this out kernel wide, and right now the kernel doesn't support different dev_t / fsids inside a single file syste at all. SuSE hacks around that badly for limited user interfaces with the horrible get_inode_dev method they've added, but this has been rejected upstream for good reason. What this series does is to add another limited version of this through the backdoor.
