absolute vs. relative offsets in disklabel

Roman Kurakin rik at inse.ru
Mon Aug 7 21:06:50 UTC 2006


John Baldwin:

>On Sunday 06 August 2006 10:59, Dmitry Marakasov wrote:
>  
>
>>* Dag-Erling Sm?rgrav (des at des.no) wrote:
>>    
>>
>>>>Recent `disklabel differences FreeBSD, DragonFly' thread gave me a
>>>>thought - why do we have absolute offsets in disklabel?
>>>>        
>>>>
>>>We don't, AFAIK.  Since the transition to GEOM, the offsets are
>>>relative to the start of the containing provider.
>>>      
>>>
>>It has nothing to do with GEOM, it's ondisk format of disklabel. I've
>>confirmed, there are global offsets.
>>    
>>
>
>Actually, the GEOM provider goes though some gymnastics to portray the offsets 
>as relative to userland, but ondisk they are still stored as absolute to 
>preserve compatiblity.
>  
>
You mean that "read mbroffset" to geom could return a relative value?

rik




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