[Xen-devel] How HVM domain distingush ioemu disk and VBD disk

["Yu, Ke" <ke.yu@xxxxxxxxx>]

Hi, 

From cset 10921, ioemu: prefix is removed from disk config in 
/etc/xen/xmexample.hvm. Now HVM VBD driver is available, this thus raises a 
question: how would HVM domain know if one disk is a qemu-dm disk or a VBD disk?

From current implementation, qemu-dm will recognize disk had, hdb, hdc, hdd, 
and VBD drive can recognize all disk (had~hdd, hde, hdf ...) . So the result 
is: qemu-dm will mount /dev/hda-hdd, and VBD driver will mount the rest 
(/dev/hde,...). Actually, VBD will also try to mount /dev/hda..., but failed 
with error message "register_blkdev: cannot get major 3 for ide", since the 
/hda is already mounted as qemu-dm disk.

This looks a litt bit confusing. So I just wonder: is this the expected 
behavor? Do we intend having some explicit mechanism to indentify ioemu disk 
and VBD disk? 

Best Regards
Ke

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel