From owner-freebsd-geom@FreeBSD.ORG Mon Mar 12 14:30:18 2007 Return-Path: X-Original-To: freebsd-geom@freebsd.org Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id E7EEE16A403; Mon, 12 Mar 2007 14:30:18 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: from mail.garage.freebsd.pl (arm132.internetdsl.tpnet.pl [83.17.198.132]) by mx1.freebsd.org (Postfix) with ESMTP id 751CD13C448; Mon, 12 Mar 2007 14:30:18 +0000 (UTC) (envelope-from pjd@garage.freebsd.pl) Received: by mail.garage.freebsd.pl (Postfix, from userid 65534) id 02C68487F3; Mon, 12 Mar 2007 15:30:12 +0100 (CET) Received: from localhost (pc-ab234.wlan.inet.fi [193.211.2.234]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.garage.freebsd.pl (Postfix) with ESMTP id E31D445CD9; Mon, 12 Mar 2007 15:30:05 +0100 (CET) Date: Mon, 12 Mar 2007 15:28:46 +0100 From: Pawel Jakub Dawidek To: Dag-Erling Sm?rgrav Message-ID: <20070312142846.GA3747@garage.freebsd.pl> References: <20070120073117.GB60202@x12.dk> <200703061246.09687.antik@bsd.ee> <45ED5850.6050506@nipsi.de> <200703061420.36980.antik@bsd.ee> <20070307135017.GC2864@garage.freebsd.pl> <45F2EEBD.6070007@barryp.org> <86ps7evniu.fsf@dwp.des.no> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="/04w6evG8XlLl3ft" Content-Disposition: inline In-Reply-To: <86ps7evniu.fsf@dwp.des.no> X-PGP-Key-URL: http://people.freebsd.org/~pjd/pjd.asc X-OS: FreeBSD 7.0-CURRENT i386 User-Agent: mutt-ng/devel-r804 (FreeBSD) X-Spam-Checker-Version: SpamAssassin 3.0.4 (2005-06-05) on mail.garage.freebsd.pl X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=BAYES_00 autolearn=ham version=3.0.4 Cc: freebsd-fs@FreeBSD.org, freebsd-geom@freebsd.org, Barry Pederson Subject: Re: zfs_20070303.patch on current X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 12 Mar 2007 14:30:19 -0000 --/04w6evG8XlLl3ft Content-Type: text/plain; charset=iso-8859-2 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Mar 12, 2007 at 10:06:49AM +0100, Dag-Erling Sm?rgrav wrote: > Barry Pederson writes: > > Is there any hope for someday optionally using ZFS as a root filesystem? >=20 > For that to be possible, both /boot/boot2 and /boot/loader need to > understand ZFS well enough to read files from it. There isn't much > room to spare in /boot/boot2, so we'd have to have a separate version > for ZFS and teach 'disklabel -B' how to pick the right one. This would be hard, I fully agree. > > I was sort of imagining a setup where /boot resided in a UFS > > filesystem so it could hold the kernel/modules/regular booting info > > and - > > /boot/loader.conf would specify 'zfs_load=3D"YES"' along with another > > directive to tell which zfs filesystem to use as root. >=20 > Unlike Linux, where this is a common configuration, FreeBSD can't > mount a root filesystem underneath an already mounted /boot > filesystem. [...] We don't have to mount /boot/ to read from it. The loader reads directly =66rom boot partition, so bascially we could make /dev/ad0s1a a small UFS partition that contains the kernel, zfs kernel module and /etc/fstab and it should work. Note that we currently allow for encrypting root file system the same way with geli(8). > [...] Nor do we have anything resembling Linux's pivot_root > which would allow us to mount the root filesystem on top of /boot and > then switch them around. Actually we do something like this for devfs, AFAIK - we first mount devfs as root file system, then we mount the right root on top of it and move devfs to /dev/. --=20 Pawel Jakub Dawidek http://www.wheel.pl pjd@FreeBSD.org http://www.FreeBSD.org FreeBSD committer Am I Evil? Yes, I Am! --/04w6evG8XlLl3ft Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.6 (FreeBSD) iD8DBQFF9WOeForvXbEpPzQRAkrGAKD4V0rKEcLNG7i8eB0oNkZQuaCmcgCePvmv 3BOSUErlCSClU/sJ03f+mHA= =ghFL -----END PGP SIGNATURE----- --/04w6evG8XlLl3ft--