Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uflorida!stat!vsserv!loligo.cc.fsu.edu!nall
From: nall@loligo.cc.fsu.edu (John Nall)
Newsgroups: comp.os.minix
Subject: Re: Large Disks
Message-ID: <241@vsserv.scri.fsu.edu>
Date: 3 Oct 89 23:43:45 GMT
Sender: news@vsserv.scri.fsu.edu
Reply-To: nall@loligo.cc.fsu.edu (John Nall)
Organization: Florida State University
Lines: 35

In a previous message, I complained about the inability
of Minix to use partitions greater than 32 MB.  In response,
Andy posed a general question as to what problems might
exist regarding this.

This is kind of an "alpha version" of tentative results of
an investigation (that is, take it with a grain of salt, but
it might be useful....I'll report in greater detail later).

Fdisk seems to have no problem making a partition greater
than 32 MB.  Be aware that you should give it a parameter
as to how many heads your disk has!  Otherwise, he makes the
assumption that it only has four!  So use  "fdisk -5"
(or whatever).

Mkfs has a couple of easily solved problems.  There is a 
variable called "blocks" which is declared as int.  It should
be unsigned int.  There is also a variable called "nrblocks"
which has the same problem.  There is also a #define statement
which declares N_BLOCKS to be 32000.  I set this to 65528 (as
it specifies that it has to be divisible by 8, and 65536 would
be a little big, I would think).

After this, mkfs /dev/hd5 40000 worked OK.  Prior to that, it
would work for 32767 but blew up on 32768 (and greater).  This
also implies that at_wini works OK, since it writes the last
block!

After I check further, I'll post patches.


======================================================================
John Nall                              Internet:  nall@nu.cs.fsu.edu
Computer Science Department            Florida State University
    "Today, a Moon Moth -- tomorrow, a Sea Dragon Conquerer!!"