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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 11 Aug 2020 09:09:36 -0700
Message-ID: <CAHk-=wgHZig-+dXQeW4pPEjdYsrq=3bgc+vUhwiT2Ox4ipLHwg@mail.gmail.com>
Subject: Re: file metadata via fs API (was: [GIT PULL] Filesystem Information)
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Miklos Szeredi <miklos@szeredi.hu>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        David Howells <dhowells@redhat.com>,
        Karel Zak <kzak@redhat.com>, Jeff Layton <jlayton@redhat.com>,
        Miklos Szeredi <mszeredi@redhat.com>,
        Nicolas Dichtel <nicolas.dichtel@6wind.com>,
        Christian Brauner <christian@brauner.io>,
        Lennart Poettering <lennart@poettering.net>,
        Linux API <linux-api@vger.kernel.org>,
        Ian Kent <raven@themaw.net>,
        LSM <linux-security-module@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Tue, Aug 11, 2020 at 9:05 AM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> Except that you suddenly see non-directory dentries get children.
> And a lot of dcache-related logics needs to be changed if that
> becomes possible.

Yeah, I think you'd basically need to associate a (dynamic)
mount-point to that path when you start doing O_ALT. Or something.

And it might not be reasonably implementable. I just think that as
_interface_ it's unambiguous and fairly clean, and if Miklos can
implement something like that, I think it would be maintainable.

No?

                Linus