Re: [Qemu-devel] Locking block devices for concurrent access?

["Richard W.M. Jones" <rjones@redhat.com>]

On Thu, Apr 22, 2010 at 01:36:30PM -0500, Anthony Liguori wrote:
> I think we got to the point where there was general agreement on the  
> usefulness of lock=read|write but where there was still some contention  
> was on this whole notion of lock=exclusive|shared.
>
> I believe Richard Jones was driving the original patch and his use case  
> was libguestfs which really wants lock=exclusive (sort of).  But IMHO,  
> it's very confusing compared to lock=read|write.

>From the libguestfs point of view, any sort of locking would be
preferable to the current situation.  If someone wants to run with the
patch, I posted several versions and there was a lot of discussion on
qemu-devel in Nov/Dec 2009, starting with this message:

  Subject: [Qemu-devel] [PATCH] Disk image shared and exclusive locks.
  Message-ID: <20091204165301.GA4167@amd.home.annexia.org>

Rich.

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