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Message-ID: <4a712f3618835ac9ba0db8d26630f8edf209a193.camel@themaw.net>
Subject: Re: [RFC PATCH] getting misc stats/attributes via xattr API
From:   Ian Kent <raven@themaw.net>
To:     Vivek Goyal <vgoyal@redhat.com>,
        Christian Brauner <brauner@kernel.org>
Cc:     Amir Goldstein <amir73il@gmail.com>,
        Miklos Szeredi <miklos@szeredi.hu>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Dave Chinner <david@fromorbit.com>,
        Theodore Ts'o <tytso@mit.edu>, Karel Zak <kzak@redhat.com>,
        Greg KH <gregkh@linuxfoundation.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
        Linux API <linux-api@vger.kernel.org>,
        linux-man <linux-man@vger.kernel.org>,
        LSM <linux-security-module@vger.kernel.org>,
        David Howells <dhowells@redhat.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <christian@brauner.io>,
        James Bottomley <James.Bottomley@hansenpartnership.com>
Date:   Tue, 10 May 2022 11:34:39 +0800
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On Mon, 2022-05-09 at 17:42 -0400, Vivek Goyal wrote:
> On Mon, May 09, 2022 at 05:08:56PM +0200, Christian Brauner wrote:
> 
> [..]
> > Having "xattr" in the system call name is just confusing. These are
> > fundamentally not "real" xattrs and we shouldn't mix semantics.
> > There
> > should be a clear distinction between traditional xattrs and this
> > vfs
> > and potentially fs information providing interface.
> > 
> > Just thinking about what the manpage would look like. We would need
> > to
> > add a paragraph to xattr(7) explaining that in addition to the
> > system.*,
> > security.*, user.* and other namespaces we now also have a set of
> > namespaces that function as ways to get information about mounts or
> > other things instead of information attached to specific inodes.
> > 
> > That's super random imho. If I were to be presented with this
> > manpage
> > I'd wonder if someone was too lazy to add a proper new system call
> > with
> > it's own semantics for this and just stuffed it into an existing
> > API
> > because it provided matching system call arguments. We can add a
> > new
> > system call. It's not that we're running out of them.
> 
> FWIW, I also felt that using xattr API to get some sort of mount info
> felt
> very non-intutive.

Yeah, people looking for this function simply wouldn't know to
look here ...

Ian