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From:   Miklos Szeredi <miklos@szeredi.hu>
Date:   Mon, 14 Nov 2022 13:35:54 +0100
Message-ID: <CAJfpegsVsnjUy2N+qO-j4ToScwev01AjwUA0Enp_DxroPQS30A@mail.gmail.com>
Subject: Re: [RFC PATCH] getting misc stats/attributes via xattr API
To:     Abel Wu <wuyun.abel@bytedance.com>
Cc:     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>,
        Christian Brauner <brauner@kernel.org>,
        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>,
        Amir Goldstein <amir73il@gmail.com>,
        James Bottomley <James.Bottomley@hansenpartnership.com>
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On Mon, 14 Nov 2022 at 10:00, Abel Wu <wuyun.abel@bytedance.com> wrote:
>
> Hi Miklos and anyone interested in this proposal, is there any update on
> this? Sorry that I didn't find any..

No update.

Which part are you interested in?

Getting mount attributes?  Or a generic key-value retrieval and
storage interface?

For the first one there are multiple proposals, one of them is adding
a new system call using binary structs.  The fsinfo(2) syscall was
deemed overdesigned and rejected.  Something simpler would probably be
fairly uncontroversial.

As for the other proposal it seems like some people would prefer a set
of new syscalls, while some others would like to reuse the xattr
syscalls.  No agreement seems to have been reached.

Also I think a notification system for mount related events is also a
much needed component.   I've tried to explore using the fsnotify
framework for this, but the code is pretty convoluted and I couldn't
get prototype working.

Thanks,
Miklos