Path: utzoo!attcan!uunet!van-bc!lpami
From: lphillips@lpami.wimsey.bc.ca (Larry Phillips)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Harddisks/Bitmaps/FFS
Message-ID: <2320@van-bc.UUCP>
Date: 12 Mar 89 00:29:31 GMT
Sender: lpami@van-bc.UUCP
Lines: 25

In <8903091628.AA05318@jade.berkeley.edu>, G35@DHDURZ1.BITNET (Werner Guenther) writes:
>I'm currently writing (yet another) program to recover damaged disks, but
>I have one big problem:
>What is the maximum size of a partition under FFS ? Under the old file
>system the root block has room for 26 pointers to bit map blocks, giving
>26*127*32=105664 sectors or about 52.5 megabytes.
>As far as I know, FFS does not such a limitation.
>What exactly did change ? Are those bitmap blocks linked together somehow ?
>If yes, how ?

 The FFS supports a 2 Gigabyte partition (all bits bu the sign in a longword).

 The extra bitmap block pointers are kept in a 'bitmap extension' block,
pointed to by the contents of longword $68 in the root block.

-larry

--
Frisbeetarianism: The belief that when you die, your soul goes up on
                  the roof and gets stuck.
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|   //   Larry Phillips                                                |
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