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Date:   Fri, 20 May 2022 04:07:23 +0000
From:   Al Viro <viro@zeniv.linux.org.uk>
To:     Miklos Szeredi <miklos@szeredi.hu>
Cc:     linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Vivek Goyal <vgoyal@redhat.com>,
        Dharmendra Singh <dharamhans87@gmail.com>,
        Bernd Schubert <bschubert@ddn.com>
Subject: Re: [RFC PATCH] vfs: allow ->atomic_open() on positive
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On Thu, May 19, 2022 at 04:43:58PM +0200, Miklos Szeredi wrote:
> Hi Al,
> 
> Do you see anything bad with allowing ->atomic_open() to take a positive dentry
> and possibly invalidate it after it does the atomic LOOKUP/CREATE+OPEN?
> 
> It looks wrong not to allow optimizing away the roundtrip associated with
> revalidation when we do allow optimizing away the roundtrip for the initial
> lookup in the same situation.

Details, please - what will your ->atomic_open() do in that case?