Re: [SeaBIOS] [Xen-devel] Question on virtual block device

[Ian Campbell]

On Thu, 2011-10-27 at 17:14 +0100, Daniel Castro wrote:
> Hello All,
>
> I am connecting my front and back for a block device.
> I have collected from xenstore sectors, sector-size. But I also need:
>     u16 heads;      // # heads
>     u16 cylinders;  // # cylinders
>     u16 spt;        // # sectors / track
> I guess from the SeaBIOS perspective they are required, but from the
> xen perspective how can I get them? pure math/translation?

CHS is rather historical and has no real relevance to a virtual device.
You can basically just make them up to fit the underlying device size,
take a look at blkif_getgeo in Linux for example.

Ian.