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Date: Wed, 27 Mar 2013 11:27:53 +0100
From: Stefan Hajnoczi <stefanha@gmail.com>
Message-ID: <20130327102753.GA6635@stefanha-thinkpad.muc.redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 21/21] qcow2: Gather clusters in a
 looping loop
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To: Kevin Wolf <kwolf@redhat.com>
Cc: qemu-devel@nongnu.org, stefanha@redhat.com

On Tue, Mar 26, 2013 at 05:50:13PM +0100, Kevin Wolf wrote:
> @@ -793,6 +793,13 @@ static int handle_dependencies(BlockDriverState *bs, uint64_t guest_offset,
>                  bytes = 0;
>              }
>  
> +            /* Stop if already an l2meta exists. We would have to consider
> +             * locks held by it (l2_writeback_lock) and set m->next etc. */

l2_writeback_lock does not exist (yet).

> +            if (bytes == 0 && *m) {
> +                *cur_bytes = 0;
> +                return 0;
> +            }