On Wed, Apr 12, 2023 at 5:21 PM Miklos Szeredi <miklos@xxxxxxxxxx> wrote: > > 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? > OK. > > > > 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? Yes, that's what he wanted. to hide the subdirs being redirected to from the namespace. > > I guess that's not something that works today. Or am I mistaken? You are not mistaken, it is not working today. > > 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. Yap, that's what I thought. Thanks, Amir.
