Path: utzoo!attcan!uunet!husc6!bloom-beacon!apple!voder!pyramid!oliveb!tymix!antares!jms
From: jms@antares.UUCP (joe smith)
Newsgroups: comp.sys.amiga.tech
Subject: Giant disks
Message-ID: <176@antares.UUCP>
Date: 3 Oct 88 06:20:24 GMT
References: <4912@cbmvax.UUCP>
Reply-To: jms@antares.UUCP (joe smith)
Organization: Tymnet QSATS, San Jose CA
Lines: 22

In article <4912@cbmvax.UUCP> steveb@cbmvax.UUCP (Steve Beats) writes:
>Now I have a question.  How can we transparently handle disk media that
>has a capacity >2.5 Gigabytes.  A lot of software is going to break just
>because they've gone over 31 bits of offset (a longword becomes negative
>then).  An even larger problem exists when you go over 4.2 Gigabytes since
>that will overflow a longword. ... 
)It isn't possible to just limit partitions to less than
)2.5 Gigs since the filing system has to make it's requests in terms of
)physical blocks, not blocks relative to the start of the partition.  Anyone
)got any ideas they'd care to 
>	Steve

OK, I'll bite.  Why can't the filing system use logical blocks?  Regardless
of the current data structures that the harddisk.device uses, why can't it
add a cylinder (or block) offset after converting the request byte offset
into block # and offset with block?

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