From mboxrd@z Thu Jan  1 00:00:00 1970
From: Miklos Szeredi <miklos@szeredi.hu>
Subject: Re: [PATCH v2 05/11] ovl: lookup redirect by file handle
Date: Fri, 28 Apr 2017 11:37:07 +0200
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To: Amir Goldstein <amir73il@gmail.com>
Cc: "linux-unionfs@vger.kernel.org" <linux-unionfs@vger.kernel.org>, Vivek Goyal <vgoyal@redhat.com>

On Fri, Apr 28, 2017 at 10:15 AM, Amir Goldstein <amir73il@gmail.com> wrote:

> Well, we could add configuration options to decide if and how to follow
> and verify fh for non-dir, but:
>
> 1. We agreed that trying to follow fh for non-dir is a no-loose situation
>     for !redirect and hot cache case and a probable win for redirect with
>     cold case

Okay.  That also means that redirect is not actually needed for
non-dir.  Well, except for the weird case of having to reconstruct a
reverse mapping after copying the layers in order to properly handle
copy up of hardlinks on the lower layer.  But lets not care about that
for now (or ever, probably).

> 2. For snapshots the behavior should be the same -
>     use the lower ino if you can find and hold lower inode
>     use upper ino otherwise (i.e. snapshots are not binding the inode
>     numbers forever)
>
> So I see no reason, going forward, to provide a user configuration
> for the lookup of non-dir.

Good.

Thanks,
Miklos