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Date: Tue, 18 Jan 2011 10:35:39 -0200
From: Luiz Capitulino <lcapitulino@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 0/3] allow online resizing of block devices
Message-ID: <20110118103539.131ee08a@doriath>
In-Reply-To: <20110114162044.GA19114@lst.de>
References: <20110114162044.GA19114@lst.de>
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To: Christoph Hellwig <hch@lst.de>
Cc: qemu-devel@nongnu.org, Markus Armbruster <armbru@redhat.com>

On Fri, 14 Jan 2011 17:20:44 +0100
Christoph Hellwig <hch@lst.de> wrote:

> This patchset adds support for online resizing of block devices.
> 
> The first patch adds a new resize monitor command which call into
> the existing image resize code.  This is the meat of the series
> and probably needs quite a bit of review and help as I'm not sure
> about how to implement the error handling for monitor commands
> correctly.  Am I really supposed to add a new QERR_ definition
> for each possible error?  And if yes how am I supposed to define
> them?  The macros for them aren't exactly self-explaining.

Well, what happens is this: we screwed up with that interface and we
should replace it soon.

I see you're not adding the new command in QMP (only in the human monitor),
is that intentional? (qmp commands are added to the qmp-commands.hx file).

If it's intentional, then using only error_report() should be ok. If you
plan to have a qmp version, then we'll have to choose between reporting
a generic error version to the client, which is what's going to happen if
you use error_report(), or add the QERR_ macros.

Markus, what do you think? I feel it's pretty urgent for us to replace
that interface.