Re: [Qemu-devel] [Qemu-block] Can I only commit from active image to corresponding range of its backing file by qemu cmd?

2018-09-27 Thread Max Reitz
On 27.09.18 16:23, Alberto Garcia wrote: > On Thu 27 Sep 2018 04:14:15 PM CEST, Max Reitz wrote: >> On 25.09.18 16:13, Alberto Garcia wrote: >>> On Thu 13 Sep 2018 08:37:05 PM CEST, Max Reitz wrote: First, split .003 into the part we want to commit and the part we don't want to commit. T

Re: [Qemu-devel] [Qemu-block] Can I only commit from active image to corresponding range of its backing file by qemu cmd?

2018-09-27 Thread Alberto Garcia
On Thu 27 Sep 2018 04:14:15 PM CEST, Max Reitz wrote: > On 25.09.18 16:13, Alberto Garcia wrote: >> On Thu 13 Sep 2018 08:37:05 PM CEST, Max Reitz wrote: >>> First, split .003 into the part we want to commit and the part we >>> don't want to commit. This is a bit tricky without qemu-img dd @seek >

Re: [Qemu-devel] [Qemu-block] Can I only commit from active image to corresponding range of its backing file by qemu cmd?

2018-09-27 Thread Max Reitz
On 25.09.18 16:13, Alberto Garcia wrote: > On Thu 13 Sep 2018 08:37:05 PM CEST, Max Reitz wrote: >> First, split .003 into the part we want to commit and the part we >> don't want to commit. This is a bit tricky without qemu-img dd @seek >> (or a corresponding convert parameter), so we'll have to

Re: [Qemu-devel] [Qemu-block] Can I only commit from active image to corresponding range of its backing file by qemu cmd?

2018-09-25 Thread Eric Blake
On 9/25/18 9:13 AM, Alberto Garcia wrote: If you only want to copy parts of a backing file I think it's much simpler if you use copy-on-read: qemu-io -C -c 'read 0 1M' img.003.commit.000 Oh, slick. $ qemu-img convert -O qcow2 \ "json:{'driver':'null-co','size':1048576}" \ "json:

Re: [Qemu-devel] [Qemu-block] Can I only commit from active image to corresponding range of its backing file by qemu cmd?

2018-09-25 Thread Alberto Garcia
On Thu 13 Sep 2018 08:37:05 PM CEST, Max Reitz wrote: > First, split .003 into the part we want to commit and the part we > don't want to commit. This is a bit tricky without qemu-img dd @seek > (or a corresponding convert parameter), so we'll have to make do with > backing=null so we don't copy a

Re: [Qemu-devel] [Qemu-block] Can I only commit from active image to corresponding range of its backing file by qemu cmd?

2018-09-21 Thread Alberto Garcia
On Fri 14 Sep 2018 04:19:01 AM CEST, lampahome wrote: > I figure out one way is to *divide data of device into 1TB chunk* and > save every chunk into qcow2 image cuz I don't change filesystem, and > connect with backing chain. Let's see if I understood what you want: 1) you have for example a 3