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Date:   Mon, 9 May 2022 17:42:41 -0400
From:   Vivek Goyal <vgoyal@redhat.com>
To:     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>,
        Ian Kent <raven@themaw.net>,
        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>
Subject: Re: [RFC PATCH] getting misc stats/attributes via xattr API
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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.

Thanks
Vivek