On Wed, Jan 09, 2013 at 09:37:54PM +0000, Blue Swirl wrote: > On Wed, Jan 9, 2013 at 7:31 AM, 马磊 <aware....@gmail.com> wrote: > > > > > >>> Hi, > >>> The final effect is as follows: > >>> > >>> > >>> [malei@xentest-4-1 Fri Dec 28 ~/honeypot/xen/xen-4.1.2]$ qemu-img-xen cat > >>> -f /1/boot.ini ~/vm-check.img > >>> [boot loader] > >>> timeout=30 > >>> default=multi(0)disk(0)rdisk(0)partition(1)\WINDOWS > >>> [operating systems] > >>> multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Microsoft Windows XP > >>> Professional" /noexecute=optin /fastdetect > >>> > >>> [malei@xentest-4-1 Fri Dec 28 ~/honeypot/xen/xen-4.1.2]$ qemu-img-xen ls > >>> -l -d /1/ ~/vm-check.img > >>> 【name size(bytes) dir? date > >>> create-time】 > >>> AUTOEXEC.BAT 0 file 2010-12-22 17:30:37 > >>> boot.ini 211 file 2010-12-23 01:24:41 > >>> bootfont.bin 322730 file 2004-11-23 20:00:00 > >>> > >>> > >>> > >>> As you see above, the patch add two sub-commands for qemu-img-xen:cat and > >>> ls. > >>> > >>> For details in the patch, please check the attachment. > >>> > >>> > > > > Does anyone prefer this feature?! > > Nice feature, but this approach would just clutter QEMU and give only > readonly FAT or NTFS support. I think a more generally useful approach > would be to use NBD or iSCSI to export the block device data from the > image file (qemu-nbd already exists) and then make a tool that uses > some combination of NBD/iSCSI client, all GRUB file systems and FUSE > or other user space methods to access the contents of the filesystem. > Probably also UML with a simple guest agent could provide read/write > access to any file system that Linux supports.
The latter is what libguestfs already provides. It boots a Linux kernel and mini initrd containing a guest agent, to provide APIs to do arbitrary manipulation of guest OS images. The reason libguestfs used a linux guest was precisely to avoid having to re-implement drivers for every filesystem in existance like this patch is trying todo. I don't think QEMU wants to be in the business of maintaining filesystem drivers, so I'd reject this proposed patch. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|