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To: jesse@wingnet.net
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Thu, 20 May 2004 14:44:06 EDT."
             <c8iu9o$jd9$1@sea.gmane.org> 
Date: Thu, 20 May 2004 21:40:37 +0200
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cc: freebsd-current@freebsd.org
Subject: Re: GEOM portable filesystem abstraction? 
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In message <c8iu9o$jd9$1@sea.gmane.org>, Jesse Guardiani writes:
>Hello,
>
>I know next to nothing about GEOM, other than what
>the man page says (which I admittedly didn't read
>in full), so I'm probably totally off base, but I
>thought I'd ask this anyway:
>
>It seems like GEOM functions as a bit of a disk
>abstraction layer in FreeBSD. Would it be possible
>to port the GEOM subsystem as a loadable kernel
>module to Linux (and perhaps other OSes) to
>facilitate pluggable, portable filesystem code?

Port it: yes.

Portable filesystem code: no.

>Perhaps if GEOM were ported to Linux then Linux
>could use FreeBSD's UFS2 code to read FreeBSD UFS
>filesystems?

No, for that you need to port the UFS code from freebsd.

GEOM operates at the sector level and does things like
mirror, stripe, RAID etc, but it sits under the filesystem
and doesn't know anything about files, directories etc.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.