From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:43935)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <kwolf@redhat.com>) id 1YPshH-000844-Au
	for qemu-devel@nongnu.org; Mon, 23 Feb 2015 08:05:16 -0500
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <kwolf@redhat.com>) id 1YPshC-00025r-Bt
	for qemu-devel@nongnu.org; Mon, 23 Feb 2015 08:05:15 -0500
Received: from mx1.redhat.com ([209.132.183.28]:39944)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <kwolf@redhat.com>) id 1YPshC-00025l-5U
	for qemu-devel@nongnu.org; Mon, 23 Feb 2015 08:05:10 -0500
Date: Mon, 23 Feb 2015 14:04:26 +0100
From: Kevin Wolf <kwolf@redhat.com>
Message-ID: <20150223130426.GD4302@noname.str.redhat.com>
References: <cover.1424439295.git.berto@igalia.com>
	<49b845c4a362ffd64ec78bbe0b165cd7addd2a4b.1424439295.git.berto@igalia.com>
	<54E7B74C.7010307@redhat.com> <20150223122308.GA11820@igalia.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20150223122308.GA11820@igalia.com>
Subject: Re: [Qemu-devel] [PATCH 2/3] block: Add QMP support for streaming
 to an intermediate layer
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Alberto Garcia <berto@igalia.com>
Cc: qemu-devel@nongnu.org, Stefan Hajnoczi <stefanha@redhat.com>, armbru@redhat.com

Am 23.02.2015 um 13:23 hat Alberto Garcia geschrieben:
> On Fri, Feb 20, 2015 at 03:38:04PM -0700, Eric Blake wrote:
> 
> > > +    if (has_top) {
> > > +        top_bs = bdrv_find_backing_image(bs, top);
> > > +        if (top_bs == NULL) {
> > > +            error_set(errp, QERR_TOP_NOT_FOUND, top);
> > > +            goto out;
> > > +        }
> > 
> > If I understand correctly, bdrv_find_backing_image has problems for
> > backing nodes that don't have a file name.  Given our shift towards
> > node names, I think we really want to target node names rather than
> > file names when specifying which node we will use as the top bound
> > receiving the stream operations.
> 
> Sure I can change that, but note that the 'base' parameter also
> receives a file name and uses bdrv_find_backing_image, so I guess it
> makes sense to change it in both sides.

Yes, using the file name for identifying nodes was a mistake. We're
going to replace all occurrences of it sooner or later. Not sure if
someone is actively working on this currently - Markus?

For your patch series, I think it's good enough to use node names for
the new parameter. Converting old parameters is a separate issue.

Kevin