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Date: Fri, 12 Dec 2008 21:35:42 +0100
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [RFC] Replace posix-aio with custom thread pool
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Andrea Arcangeli <aarcange@redhat.com>, qemu-devel@nongnu.org, kvm-devel <kvm@vger.kernel.org>

Anthony Liguori wrote:
> I don't know about grant table references b/c that's really foreign
> memory.  But this is a good argument against the DMA as it stands, b/c
> you may be handing foreign memory to bdrv_aio_readv/writev.
> 
> A big reason for the map/unmap lock/unlock abstraction though would be
> the qemu-dm map cache.  I think you could use it to pretty reasonably
> integrate the map cache which I know I've previously could never be done
> :-)

I see we fully agree here.

/me mumbles something about funny mail crossings.
Maybe we should use irc next time to save some typing ;)

cheers,
  Gerd