From: Kevin Wolf <kwolf@redhat.com>
To: Anthony Liguori <anthony@codemonkey.ws>
Cc: QEMU Developers <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] [PATCH] qcow2: Allow qcow2 disk images with size zero
Date: Tue, 27 Oct 2009 17:44:37 +0100 [thread overview]
Message-ID: <4AE72375.3000003@redhat.com> (raw)
In-Reply-To: <4AE6FFAF.6010405@codemonkey.ws>
Am 27.10.2009 15:11, schrieb Anthony Liguori:
> Stefan Weil wrote:
>> Images with disk size 0 may be used for
>> VM snapshots, but not to save normal block data.
>>
>> It is possible to create such images using
>> qemu-img, but opening them later fails.
>>
>> So even "qemu-img info image.qcow2" is not
>> possible for an image created with
>> "qemu-img create -f qcow2 image.qcow2 0".
>>
>> This is fixed here.
>>
>> Signed-off-by: Stefan Weil <weil@mail.berlios.de>
>>
>
> What do you think Kevin?
That with malloc instead of qemu_malloc the patch would have been a bit
smaller. ;-) I think it can make sense to have such images in some cases
(although a 64k image isn't much worse) and I don't see any obvious
problem with the patch. Not sure how guests like 0 byte disks, but I
assume Stefan has tested that.
I'm just wondering how Stefan did create his test image - with current
qemu-img I can't create such images, so I needed to patch it first. For
this one I'll send a fix.
Kevin
next prev parent reply other threads:[~2009-10-27 16:45 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-10-26 15:11 [Qemu-devel] [PATCH] qcow2: Allow qcow2 disk images with size zero Stefan Weil
2009-10-27 14:11 ` Anthony Liguori
2009-10-27 16:44 ` Kevin Wolf [this message]
2009-10-27 17:17 ` Stefan Weil
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