Re: [dm-devel] [PATCH] Support HDIO_GETGEO on device-mapper volumes

[Molle Bestefich <molle bestefich gmail com>]

Darrick J. Wong wrote:
> I'm trying to install grub on a device-mapper RAID1 array that I set up
> via dmraid (in other words, a bootable software fakeraid).  Since dm
> doesn't implement the HDIO_GETGEO ioctl, grub assumes that the CHS
> geometry is 620/128/63, which makes it impossible to configure it to
> boot a filesystem that lives beyond the 2GB mark, even if the system
> BIOS supports that.
>
> The attached patch implements a simple ioctl handler that supplies a
> compatible geometry when HDIO_GETGEO is called against a device-mapper
> device.

FYI, I made a patch a year ago or so that achieves the same, only in GRUB land.
I like your approach just as well (and my patch was ugly and needed
TLC badly), so cool.

You might want to cc: your patch to Peter Jones or someone from Fedora Core,
just in case they picked up that ugly Grub thing I did, so they can
remove that and use yours instead :-)...