Re: partition types

[Sven Luther <sven.luther@wanadoo.fr>]

On Wed, Oct 22, 2003 at 12:43:05PM +0200, Geert Stappers wrote:
> On Wed, Oct 22, 2003 at 10:40:14AM +0200, Martin Sj?gren wrote:
> > ons 2003-10-22 klockan 05.42 skrev Chris Tillman:
> > > On Tue, Oct 21, 2003 at 08:56:39PM -0400, Joey Hess wrote:
> > > > 
> > > > In cfdisk, I told it to change my 128 mb swap partition to ext2, and
> > > > write and quit. For some reason the next screen (picking partitions to
> > > > mount?) still identified it as type swap. I went back and checked, it
> > > > was ext2 according to fdisk. Still swap as far as d-i knew, but I went
> > > > ahead and told it to mount that as the root partition. Lacking any other
> > > > partitions, I continued with the install.
> > > 
> > > I think it identifies it as swap because it's looking at the filesystem
> > > that's present on the partition, not the partition type.
> > 
> > Exactly. Are the "partition types" really useful anyway?
> > 
> 
> In a partition program like cfdisk you expect that it uses partition types.
> So yes, they are usefull.

This is because of the design of libparted, which never uses the
partition types, altough it seems to set them correctly, probably only
when creating filesystems though, but use some heuristic to detect what
is really available as filesystem on the disk.

I don't really agree on this with upstream, but i guess upstream's word
is more important than mine on this.

So, to solve this problem, you have to use libparted to create the
filesystems too, which is not supported for all filesystems.

Another way to do that, would be to pass the partition type (or the
partition table entry) to the filesystem layer of libparted, which is
something needed for amiga filesystems anyway, but this breaks binary
compatibility, and would need a rework of libaprted's structure that
upstream doesn't agree about.

Once i finish my current work on powerpc kernel and d-i build stuff, i
will look into parted again, but i don't promise much.

BTW, i now have access to the sources of the pegasos OF, and will
implement some kind boot-loader stuff directly in the OF, and thus
wouldn't need to port yaboot2/prom-libc to it, which will anyway not be
ready in time for sarge. I plan to have it read some configuration file
on disk, and present a menu or something such. Should i go for a
lilo/yaboot like configuration file, or for a nicer grub-like format ?

Friendly,

Sven Luther