Received-SPF: pass (google.com: domain of linux-kernel+bounces-128163-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Precedence: bulk
MIME-Version: 1.0
References: <20240402-setlease-v2-1-b098a5f9295d@kernel.org>
 <8a8e8c0d-7878-4289-b490-cb9bf17e56b9@fastmail.fm> <f6bbdf158f0ca7a12de9b9f980d4d7fa31399ed9.camel@kernel.org>
 <CAOQ4uxiv7xSUS7RDK3esa1Crp8reYXewxkr5fFbhG623P20PwA@mail.gmail.com>
In-Reply-To: <CAOQ4uxiv7xSUS7RDK3esa1Crp8reYXewxkr5fFbhG623P20PwA@mail.gmail.com>
From: Miklos Szeredi <miklos@szeredi.hu>
Date: Tue, 2 Apr 2024 16:38:02 +0200
Message-ID: <CAJfpegvRDKS1kKrMPyqzmuSs8KXZ2ohpwp0nEzEf7e3vv940xg@mail.gmail.com>
Subject: Re: [PATCH v2] fuse: allow FUSE drivers to declare themselves free
 from outside changes
To: Amir Goldstein <amir73il@gmail.com>
Cc: Jeff Layton <jlayton@kernel.org>, Bernd Schubert <bernd.schubert@fastmail.fm>, 
	linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

On Tue, 2 Apr 2024 at 16:02, Amir Goldstein <amir73il@gmail.com> wrote:
>
> On Tue, Apr 2, 2024 at 4:29=E2=80=AFPM Jeff Layton <jlayton@kernel.org> w=
rote:
> >
> > On Tue, 2024-04-02 at 15:23 +0200, Bernd Schubert wrote:

> > > Could you please add something like below?
> > >
> > > FUSE_NO_OUTSIDE_CHANGES: No file changes through other mounts / clien=
ts
> > >

"through other mounts" is confusing, since one instance of the fuse
filesystem can have many mounts, and changes can be done through all
of them.   The issue is if changes are spontaneous from the viewpoint
of the fuse client.

> >
> > Definitely. I've added that in my local branch. I can either resend
> > later, or maybe Miklos can just add that if he's otherwise OK with this
> > patch.
>
> Don't love the name but don't have any suggestions either.
>
> I am wondering out loud, if we have such a mode for the fs,
> if and how should it affect caching configuration?

IMO it should enable all caching and override any conflicting options.
That's a separate patch, but should be done within the next cycle.
I'll look into that.

Thanks,
Miklos