On Wed, Jul 17, 2024 at 06:45:44PM +0200, Christoph Hellwig wrote: > On Wed, Jul 17, 2024 at 09:15:46AM -0700, Darrick J. Wong wrote: > > > So I think the package split makes sense no matter what we do, > > > but I really want a per file system choice and not a global one. > > > > <nod> How might we do that? > > > > 1. touch $mnt/.selfheal to opt-in to online fsck? > > 2. touch $mnt/.noselfheal to opt-out? > > 3. attr -s system.selfheal to opt in? > > 4. attr -s system.noselfheal to opt out? > > 5. compat feature to opt-in > > 6. compat feature to opt-out? > > 7. filesystem property that we stuff in the metadir? > > > > 1-2 most resemble the old /.forcefsck knob, and systemd has > > ConditionPathExists= that we could use to turn an xfs_scrub@<path> > > service invocation into a nop. > > > > 3-4 don't clutter up the root filesystem with dotfiles, but then if we > > ever reset the root directory then the selfheal property is lost. > > All four of of them are kinda scary that the contents of the file systems > affects policy. Now maybe we should never chown the root directory to > an untrusted or not fully trusted user, but.. > > > 5-6 might be my preferred way, but then I think I have to add a fsgeom > > flag so that userspace can detect the selfheal preferences. > > These actually sound like the most sensible to me, even if the flags > are of course a little annoying. > > > b. Adding these knobs means more userspace code to manage them. 1-4 can > > be done easily in xfs_admin, 5-8 involve a new ioctl and io/db code. > > Yeah, that's kindof the downside. > > The other option would of course be some kind of global table in /etc. You could also do: for x in <ephemeral mountpoints>; do systemctl mask xfs_scrub@$(systemd-escape --path $x) done (Though iirc xfs_scrub_all currently treats masked services as failures; maybe it shouldn't.) --D
