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Date: Wed, 10 Oct 2012 19:21:51 -0400
From: "Theodore Ts'o" <tytso@mit.edu>
To: Zach Brown <zab@redhat.com>
Cc: Kent Overstreet <koverstreet@google.com>, linux-bcache@vger.kernel.org,
        linux-kernel@vger.kernel.org, dm-devel@redhat.com
Subject: Re: [PATCH 2/5] aio: kiocb_cancel()
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On Wed, Oct 10, 2012 at 02:20:51PM -0700, Zach Brown wrote:
> 
> I sympathize, but the reality is that the current infrastructure
> is very bad and no one is using it.
> 
> It's not like we're getting rid of the syscall.  I'll be behaving
> exactly as it does today: returning the error code that indicates that
> cancellation failed because it lost the race with completion.  Every
> caller has to cope with that to use cancel safely.

Yes, I realize it doesn't work today.  But hopefully we'll be able to
reimplement it in a cleaner way.  That's why I said, I hope we don't
give up on the functionality of aio_cancel --- not that I'm against
removing what we currently have.

Cheers,

					- Ted