From owner-freebsd-hackers Wed Apr 16 22:25:02 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id WAA08829 for hackers-outgoing; Wed, 16 Apr 1997 22:25:02 -0700 (PDT) Received: from parkplace.cet.co.jp (parkplace.cet.co.jp [202.32.64.1]) by freefall.freebsd.org (8.8.5/8.8.5) with ESMTP id WAA08805 for ; Wed, 16 Apr 1997 22:24:56 -0700 (PDT) Received: from localhost (michaelh@localhost) by parkplace.cet.co.jp (8.8.5/CET-v2.1) with SMTP id FAA22640; Thu, 17 Apr 1997 05:24:44 GMT Date: Thu, 17 Apr 1997 14:24:44 +0900 (JST) From: Michael Hancock Reply-To: Michael Hancock To: Jason Scheck cc: FreeBSD Hackers Subject: Re: Feasibility of porting Linux filesystem code? In-Reply-To: <5j15f4$mmg@hoax.cse.tek.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-hackers@freebsd.org X-Loop: FreeBSD.org Precedence: bulk On 15 Apr 1997, Jason Scheck wrote: > Linux has a file system driver that I would very much like to use on my > home FreeBSD server (a Macintosh HFS driver). Assuming some driver > aptitude, what is the feasibility of converting this driver to run under > FreeBSD? Are the models totally incompatible? The vfs and vnode interfaces of various UNIX operating systems are incompatible but similar. > The DOS filesystem driver has been broken for long enough that it seems > that it might be difficult. However, it might not have been converted due File systems are difficult and you also need to know something about the VM system because of their symbiotic relationship. Both are complex systems but well worth the effort to try and understand IMHO. Someone has been working on a new msdosfs, but has been overloaded with work. > to filesystem issues. I do know that some version of the ext2fs runs > under both. Ext2fs which has been modified to use the BSD4.4 vnode interface and share some ufs inode code is being used by a number of people under FreeBSD. > Any advice will be appreciated. Take a look at some of the source sitting in /sys/miscfs and /sys/msdosfs. The book 'Unix Internals: The New Frontiers' has a lot of info on filesystems in general. 'The Design of the 4.4BSD Operating System' is also a good for info specific to 4.4 derived OSes. References in both lead to other good sources of information as well. The Linux Document project describes ext2fs and the Linux vfs/vnode implementation pretty well. Regards, Mike