On 2017-11-15 18:44, Gandalf Corvotempesta wrote:> XVA is a tar archive. > I don't think would be possible to directly use the image stored inside > without extracting and merging each chunks > > Any random reads would be impossible to do, only a huge sequential dump to > build the raw imageWell, you can't just add support to qemu-img alone either. Every image format supported by qemu-img is one supported by qemu as a whole and thus needs a proper block driver that needs to support random accesses as well. Max
Gandalf Corvotempesta
2017-Nov-15 20:06 UTC
Re: [Libguestfs] [Qemu-devel] [qemu-img] support for XVA
2017-11-15 20:59 GMT+01:00 Max Reitz <mreitz@redhat.com>:> Well, you can't just add support to qemu-img alone either. Every image > format supported by qemu-img is one supported by qemu as a whole and > thus needs a proper block driver that needs to support random accesses > as well.I was talking about qemu-img convert, just to convert an XVA image to something different, in a single pass, without having to extract the tar.
On 2017-11-15 21:06, Gandalf Corvotempesta wrote:> 2017-11-15 20:59 GMT+01:00 Max Reitz <mreitz@redhat.com>: >> Well, you can't just add support to qemu-img alone either. Every image >> format supported by qemu-img is one supported by qemu as a whole and >> thus needs a proper block driver that needs to support random accesses >> as well. > > I was talking about qemu-img convert, just to convert an XVA image to > something different, in a single pass, without having to extract the > tar.I know, but that doesn't work. qemu-img convert uses the normal general-purpose block drivers for that. Max