[PATCH olpc-os-builder 09/14 v2] sd_card_image: clean up calculations, rely on dmsetup + kpartx

[Daniel Drake]

On 17 March 2011 17:57, Sascha Silbe <silbe at activitycentral.com> wrote:
> sd_card_image previously used two mismatching C/H/S geometries internally.
> The impact on the output was minimal (the image file might have been slightly
> larger than necessary) because most of the actually used values were
> hardcoded, but it was rather confusing.
>
> By replacing the loop device offset magic with dmsetup and kpartx we can
> avoid doing some of the more problematic calculations. It also makes it
> easier to add grub support (for testing the image inside a VM).

Cleanups/corrections to the calculations in this file are welcome, but...

I'm not so keen on adding device-mapper to the mix, I'd rather keep it
using the more simple loopback devices as we have now.
olpc-os-builder once required device mapper and it didn't work out
great because the XO kernels don't have that, and I'd rather not add
support for it just for this.

What do others think?

Daniel