[Qemu-devel] [PATCH 0/2] Add serial number support for virtio_blk, V4

[john cooper <john.cooper@redhat.com>]

[Rework of earlier patch to provide additional
information in the response to an ATA identify
request -- virtio_blk treats the data as opaque,
content created by qemu's virtio-blk.  Comments
from Christoph also incorporated.]

This patch allows passing of a virtio_blk drive
serial number from qemu into a guest's virtio_blk
driver, and provides a means to access the serial
number from a guest's userspace.

Equivalent functionality currently exists for IDE
and SCSI, however it is not yet implemented for
virtio.  Scenarios exist where guest code relies
on a unique drive serial number to correctly
identify the machine environment in which it
exists.

The following two patches implement the above:

  qemu-vblk-serial-4.patch

which provides the qemu missing bits to interpret
a '-drive .. serial=XYZ ..' flag, and:

  virtio_blk-serial-4.patch

which extracts this information and makes it
available to guest userspace via an HDIO_GET_IDENTITY
ioctl, eg: 'hdparm -i /dev/vda'.

The above patches are relative to qemu-kvm.git and
2.6.29.3 respectively.

-john

-- 
john.cooper@redhat.com