On Wed, 12 Apr 2023 at 16:07, Amir Goldstein <amir73il@xxxxxxxxx> wrote: > To elaborate: > > lowerdir="lo1:lo2:lo3::do1:do2:do3" is allowed > > :: must have non-zero lower layers on the left side > and non-zero data-only layers on the right side. Okay. Can you please add this to the documentation? > > Actually, this feature originates from a request from Alexander to > respect opaque root dir in lower layers, but I preferred to make this > change of behavior opt-in so it can be tested by userspace. Not sure I get that. Does "opaque root dir" mean that only absolute redirects can access layers below such a layer? I guess that's not something that works today. Or am I mistaken? I also don't get what you mean by testing in userspace. Can you ellaborate? > > I took it one step further than the opaque root dir request - > the lookup in data-only is a generic vfs_path_lookup() of an > absolute path redirect from one of the lowerdirs, with no > checking of redirect/metacopy/opque xattrs. > > And then I only implemented lazy lookup for the lookup > in those new data-only layers, which made things simpler. Okay, makes sense. If someone hits this limitation, then we can always start thinking about generalizing this feature. > Please see the patches I just posted for details [1]. Will do. Thanks, Miklos
