Re: [Qemu-devel] [PATCH] block: default to 0 minimal / optiomal I/O size

[Christoph Hellwig]

On Fri, Jul 23, 2010 at 12:50:12PM +0200, Kevin Wolf wrote:
> This isn't reverting to the state before we reported anything, but it
> reports values of 0 now. Is this defined for both virtio-blk and SCSI to
> mean the same as no report at all? Or should we rather not advertise
> VIRTIO_BLK_F_TOPOLOGY (and the SCSI equivalent) in this case?

For scsi it's explicitly defined that way, and there is not equivalent
to the VIRTIO_BLK_F_TOPOLOGY because it will just use the VPD data if
the page is long enough.  virtio is a bit underspecified, but the
Linux guest driver has the same behaviour as scsi in that respect.