On Fri, 21 Jul 2023, Dave Chinner wrote:
I suspect that this is one of those catch-22 situations: distros are going to enable every feature under the sun. That doesn't mean that anyone is actually _using_ them these days.
I think the value of filesystem code is not just a question of how often it gets executed -- it's also about retaining access to the data collected in archives, museums, galleries etc. that is inevitably held in old formats.
We need to much more proactive about dropping support for unmaintained filesystems that nobody is ever fixing despite the constant stream of corruption- and deadlock- related bugs reported against them.
IMO, a stream of bug reports is not a reason to remove code (it's a reason to revert some commits). Anyway, that stream of bugs presumably flows from the unstable kernel API, which is inherently high-maintenance. It seems that a stable API could be more appropriate for any filesystem for which the on-disk format is fixed (by old media, by unmaintained FLOSS implementations or abandoned proprietary implementations). Being in userspace, I suppose FUSE could be a stable API though I imagine it's not ideal in the sense that migrating kernel code there would be difficult. Maybe userspace NFS 4 would be a better fit? (I've no idea, I'm out of my depth in /fs...) Ideally, kernel-to-userspace code migration would be done with automatic program transformation -- otherwise it would become another stream of bugs.
