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From: Cedric Blancher <cedric.blancher@gmail.com>
Date: Wed, 22 Nov 2023 23:42:43 +0100
Message-ID: <CALXu0Uf9LiNL7SA57vSq5pMBVBZESWexcRwDR0XMc9fFpPiNkQ@mail.gmail.com>
Subject: Re: How to set the NFSv4 "HIDDEN" attribute on Linux?
To: Linux NFS Mailing List <linux-nfs@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"

On Mon, 20 Nov 2023 at 12:46, Jeff Layton <jlayton@kernel.org> wrote:
>
> On Sun, 2023-11-19 at 17:51 +0100, Cedric Blancher wrote:
> > On Sat, 18 Nov 2023 at 12:56, Jeff Layton <jlayton@kernel.org> wrote:
> > >
> > > On Sat, 2023-11-18 at 07:24 +0100, Cedric Blancher wrote:
> > > > Good morning!
> > > >
> > > > NFSv4 has a "hidden" filesystem object attribute. How can I set that
> > > > on a Linux NFSv4 server, or in a filesystem exported on Linux via
> > > > NFSv4, so that the NFSv4 client gets this attribute for a file?
> > > >
> > >
> > > You can't. RFC 8881 defines that as "TRUE, if the file is considered
> > > hidden with respect to the Windows API." There is no analogous Linux
> > > inode attribute.
> >
> > Can we use setfattr and getfattr to set/get the NFSv4.1 HIDDEN and
> > ARCHIVE? We have Windows NFSv4 clients (and kofemann/Roland's codebase
> > supports this), and that means we need to be able to set/get and
> > backup/restore these flags on the NFSv4 server side.
> >
>
> No. They would need to be stored in the inode on the server somehow and
> there is no place to store them. These attributes are simply not
> supported by the Linux NFS server.

Linux has xattrs, which are per inode, and can be backuped and
restored via tar --xattrs. That would be good enough

Ced
-- 
Cedric Blancher <cedric.blancher@gmail.com>
[https://plus.google.com/u/0/+CedricBlancher/]
Institute Pasteur