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From:   Miklos Szeredi <mszeredi@redhat.com>
Date:   Sat, 23 May 2020 06:07:28 +0200
Message-ID: <CAOssrKcpWj=ACbNfy0iBjGDRogouDZAv-LT3P91XaXY3HD=jBA@mail.gmail.com>
Subject: Re: [PATCH] ovl: make private mounts longterm
To:     Al Viro <viro@zeniv.linux.org.uk>
Cc:     Amir Goldstein <amir73il@gmail.com>,
        overlayfs <linux-unionfs@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        lkml <linux-kernel@vger.kernel.org>
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On Fri, May 22, 2020 at 9:56 PM Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> On Fri, May 22, 2020 at 08:53:49PM +0200, Miklos Szeredi wrote:

> > Right, we should just get rid of ofs->upper_mnt and ofs->upperdir_trap
> > and use ofs->layers[0] to store those.
>
> For that you'd need to allocate ->layers before you get to ovl_get_upper(),
> though.  I'm not saying it's a bad idea - doing plain memory allocations
> before anything else tends to make failure exits cleaner; it's just that
> it'll take some massage.  Basically, do ovl_split_lowerdirs() early,
> then allocate everything you need, then do lookups, etc., filling that
> stuff.

That was exactly the plan I set out.

> Regarding this series - the points regarding the name choice and the
> need to document the calling conventions change still remain.

Agreed.

Thanks,
Miklos