Subject: Re: Supporting sector size != DEV_BSIZE
To: Darrin B. Jewell <jewell@mit.edu>
From: Bill Studenmund <wrstuden@netbsd.org>
List: tech-kern
Date: 06/26/2002 10:23:08
On Wed, 26 Jun 2002, Darrin B. Jewell wrote:

> Let me take a step down in tone.  It is not my intention to attack the
> work you are doing.  In general, I believe you know what you are
> talking about, are making the correct decisions and are working in the
> right direction.

Then I too shall step down the tone. :-) I appreciate the work you've done
on getting Apple/NeXT ufs support working.

> Bill Studenmund <wrstuden@netbsd.org> writes:
>
> Good point.  Let me retreat and suggest that changing DEV_BSIZE
> is a difficult goal.  I am looking forward to it being successfully
> accomplished.

That I agree with. It's not an easy thing to change, as this whole thread
indicates. :-)

> Good.  This is mostly what I was getting at.
>
> I am hearing you say that when you are done, I will be able to take a
> disk with 2k sectors that has a filesystem that was created on NetBSD
> 1.5 with DEV_BSIZE=2048, dd it onto a disk that has 1k sectors and
> then mount it on my system compiled with DEV_BSIZE=512.

That is the goal. :-)

> This will make me happy.

Cool.

> | > Probably not, although there was not enough information in the part I
> | > sent to see what they units they use for the cylinder block count or
> | > quota counts.  Since I can't remember offhand what I found last time
> | > I checked, I will have to look it up.
> |
> | Uhm, that's why I wanted to see an inode. :-)
>
> Ok, I have a UFS filesystem image from a NeXT 1k scsi disk as well
> as the UFS filesystem image from the NeXTstep 3.3 install CD (2k media)
> If there is a particular analysis you would like, please let me know.
> I will examine the inode again and let you know what I see.  I hope to
> have the time this weekend or over the upcoming holiday.

The main thing I had in mind is the file size in blocks and bytes should
be in there, so we should be able to get the block size. :-)

Take care,

Bill