在 2025/6/24 18:43, Christian Brauner 写道:
[...]
It's not hard for btrfs to provide it, we already have a check function
btrfs_check_rw_degradable() to do that.
Although I'd say, that will be something way down the road.
Yes, for sure. I think long-term we should hoist at least the bare
infrastructure for multi-device filesystem management into the VFS.
Just want to mention that, "multi-device filesystem" already includes
fses with external journal.
Thus the new callback may be a good chance for those mature fses to
explore some corner case availability improvement, e.g. the loss of the
external journal device while there is no live journal on it.
(I have to admin it's super niche, and live-migration to internal
journal may be way more complex than my uneducated guess)
Thanks,
Qu
Or we should at least explore whether that's feasible and if it's
overall advantageous to maintenance and standardization. We've already
done a bit of that and imho it's now a lot easier to reason about the
basics already.
We even don't have a proper way to let end user configure the device loss
behavior.
E.g. some end users may prefer a full shutdown to be extra cautious, other
than continue degraded.
Right.
