Re: GPT vs BSD-label

[christos%astron.com@localhost (Christos Zoulas)]

In article <201602082342.u18Ngfw5029915@server>,
John Nemeth  <jnemeth%cue.bc.ca@localhost> wrote:
>On Feb 8,  3:02pm, Swift Griggs wrote:
>} On Mon, 8 Feb 2016, John Nemeth wrote:
>} > Standard BSD disklabels have the same limitation as MBRs as they use 
>} > 32-bit numbers for partition start and size.
>} 
>} I take it that there is more to it than that... ? I'm sure I'm 
>} over-simplifying, but simply changing the long to a int64_t I suppose has 
>} greater impact and implications for other tools and code that read 
>} disklabels, right ?
>
>     Those problems could be solved.  Obviously, old tools wouldn't
>work with the new format; however, new tools could work with either
>format.  But, the first issue is that it is an on-disk format.
>You need to find the space to expand the disklabel and do so in a
>manner that doesn't break anything.  As demonstrated by OpenBSD,
>supposedly, this is possible (I have not examined it in any depth
>to assure myself that it doesn't break anything; I am simply aware
>of it).

OpenBSD has done it. I've made the same code changes but I stopped
just before committing because we have dozens of custom copies of disklabel
code that would need to be adjusted and tested.

christos