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Date: Thu, 1 Sep 2011 12:34:35 -0400
From: Christoph Hellwig <hch@infradead.org>
To: Jeremy Allison <jra@samba.org>
Cc: Christoph Hellwig <hch@infradead.org>,
        Ulrich Drepper <drepper@akkadia.org>,
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        Jeff Moyer <jmoyer@redhat.com>, linux-kernel@vger.kernel.org,
        linux-aio@kvack.org
Subject: Re: Approaches to making io_submit not block
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On Thu, Sep 01, 2011 at 09:31:07AM -0700, Jeremy Allison wrote:
> > We'd define a new O_LOCKS_WHATEVER flag for it, which gets set either
> > using fcntl(..., F_SETFL, ...) or dup3.  All in all that should be less
> > than 50 lines of code in the kernel.
> 
> Ok, so it'd be set at open() time, say:
> 
> O_CLOLOCK_PERSIST
> 
> (to match the naming of something like O_CLOEXEC) and be available to set
> with F_SETFD via an fcntl and dup3 call ?

Yes, that's the idea.