Thanks a lot. Much appreciate your help. Regards, Murali Balcha
On Jan 29, 2014, at 9:52 AM, "Jeff Cody" <jc...@redhat.com> wrote: > On Wed, Jan 29, 2014 at 03:35:16PM +0100, Kevin Wolf wrote: >> Am 29.01.2014 um 14:50 hat Murali Balcha geschrieben: >>> Thanks for the quick reply. The scenario I have is little different. The >>> backing file is only 40 MB where as the virtual size of qcow2 is 1GB. >>> >>> project1@cloudvault3:/tmp/20bcb425-d3c5-4c0f-819c-7c9b1a16fde3$ qemu-img >>> info 2e94bd45-7e4e-4e04-a8b4-74d579cad892_vda.qcow2 >>> image: 2e94bd45-7e4e-4e04-a8b4-74d579cad892_vda.qcow2 >>> file format: raw >>> virtual size: 39M (41126400 bytes) >>> disk size: 39M >>> project1@cloudvault3:/tmp/20bcb425-d3c5-4c0f-819c-7c9b1a16fde3$ qemu-img >>> info 2bc87796-60e8-4024-8a40-fae817e094da_vda.qcow2 >>> image: 2bc87796-60e8-4024-8a40-fae817e094da_vda.qcow2 >>> file format: qcow2 >>> virtual size: 1.0G (1073741824 bytes) >>> disk size: 3.3M >>> cluster_size: 65536 >>> backing file: >>> /tmp/20bcb425-d3c5-4c0f-819c-7c9b1a16fde3/2e94bd45-7e4e-4e04-a8b4-74d579cad >>> 892_vda.qcow2 >>> Format specific information: >>> compat: 0.10 >>> project1@cloudvault3:/tmp/20bcb425-d3c5-4c0f-819c-7c9b1a16fde3$ qemu-img >>> commit 2bc87796-60e8-4024-8a40-fae817e094da_vda.qcow2 >>> qemu-img: Error while committing image >>> >>> The qemu-img is bailing out when it detected that commit is happening >>> beyond raw backing image. >>> >>> >>> Is this a valid commit operation. This is how openstack sets up vms. >> >> This is completely unrelated to the patch that you mentioned then. >> >> The problem is that qemu-img would have to increase the image size of >> the backing file first before it can commit all the data to it. I >> believe there was a patch by Jeff (CC'ed) that would do exactly this. >> >> Kevin > > Thanks Kevin, > > Yes, the patch is in the qemu-kvm git master as of Jan 24 2014 (so it > is pretty new); here is the commit id info: > > commit 72706ea4cd38bfcb151265df0178ba21863d7518 > Author: Jeff Cody <jc...@redhat.com> > Date: Fri Jan 24 09:02:35 2014 -0500 > > block: resize backing file image during offline commit, if necessary > > > > > There is a corresponding commit for the same fix, for when you are > doing a live online block-commit to the active layer of a block image > chain: > > commit 4da83585961631bfc10831dd26c4afda2a8b23e8 > Author: Jeff Cody <jc...@redhat.com> > Date: Fri Jan 24 09:02:36 2014 -0500 > > block: resize backing image during active layer commit, if needed > > > Jeff > > >> >>> On 1/29/14, 4:24 AM, "Kevin Wolf" <kw...@redhat.com> wrote: >>> >>>> Am 29.01.2014 um 03:09 hat Murali Balcha geschrieben: >>>>> Hi, >>>>> My apologies for reaching out directly on your email. However I am new >>>>> qemu and >>>>> don¹t know the active mailing list for qemu related issues. >>>> >>>> The qemu mailing list is qemu-devel@nongnu.org. You should generally >>>> direct your questions there, though keeping individual persons in the CC >>>> list is fine. >>>> >>>>> I have seen your >>>>> name in one of the patches related to this >>>>> issue.https://github.com/gooselinux/ >>>>> qemu-kvm/blob/master/kvm-block-Fix-image-re-open-in-bdrv_commit.patch >>>>> >>>>> We are using 1.6.90 and 1.7 of qemu. the qemu-img errors out with >>>>> exact same >>>>> message when we try to commit qcow2 delta to raw image. Looking at the >>>>> code, we >>>>> realized that that patch you discussed above did not make it 1.6.90 >>>>> branch we >>>>> are using. Am I missing something. >>>> >>>> I am not sure which error message you mean, but the patch that you >>>> mentioned has been in qemu since version 0.14.0. You won't see it in the >>>> current code any more because of later changes that switched to using >>>> bdrv_reopen() instead. >>>> >>>> For me, committing to a raw image works fine with current git master: >>>> >>>> $ qemu-img create -f raw /tmp/backing.raw 4G >>>> Formatting '/tmp/backing.raw', fmt=raw size=4294967296 >>>> $ qemu-img create -f qcow2 -b /tmp/backing.raw /tmp/overlay.qcow2 >>>> Formatting '/tmp/overlay.qcow2', fmt=qcow2 size=4294967296 >>>> backing_file='/tmp/backing.raw' encryption=off cluster_size=65536 >>>> lazy_refcounts=off >>>> $ qemu-io -c 'write 0 4k' /tmp/overlay.qcow2 >>>> wrote 4096/4096 bytes at offset 0 >>>> 4 KiB, 1 ops; 0.0009 sec (4.090 MiB/sec and 1047.1204 ops/sec) >>>> $ qemu-img commit /tmp/overlay.qcow2 >>>> Image committed. >>>> >>>> Kevin >>>
