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From:   David Howells <dhowells@redhat.com>
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To:     Andy Lutomirski <luto@amacapital.net>
Cc:     dhowells@redhat.com,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Andrew Lutomirski <luto@kernel.org>,
        Al Viro <viro@zeniv.linux.org.uk>,
        Linux API <linux-api@vger.kernel.org>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Jann Horn <jannh@google.com>, Tycho Andersen <tycho@tycho.ws>
Subject: Re: [PATCH 24/32] vfs: syscall: Add fsopen() to prepare for superblock creation [ver #9]
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Date:   Fri, 13 Jul 2018 16:40:28 +0100
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Andy Lutomirski <luto@amacapital.net> wrote:

> > Whilst I'm at it, do we want the option of doing the equivalent of
> > mountat()?  I.e. offering the option to open all the device files used by
> > a superblock with dfd and AT_* flags in combination with the filename?
> > 
> 
> Isn't that more or less what I was suggesting?

Yes, you suggested that.  I'm asking if we actually need that.

> ... I also suggested just an fd and letting the caller open the file itself.

I'm not entirely sure, but that might prevent the filesystem from being able
to use it, since userspace might then prevent the filesystem getting exclusive
holdership.

David