From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1PbGN0-0008D7-ML for mharc-grub-devel@gnu.org; Fri, 07 Jan 2011 12:44:58 -0500 Received: from [140.186.70.92] (port=47996 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PbGMw-0008Cd-NE for grub-devel@gnu.org; Fri, 07 Jan 2011 12:44:56 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PbGMv-0007us-5p for grub-devel@gnu.org; Fri, 07 Jan 2011 12:44:54 -0500 Received: from mail-wy0-f169.google.com ([74.125.82.169]:43710) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PbGMu-0007uY-Sz for grub-devel@gnu.org; Fri, 07 Jan 2011 12:44:53 -0500 Received: by wyj26 with SMTP id 26so18374350wyj.0 for ; Fri, 07 Jan 2011 09:44:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from :user-agent:mime-version:to:subject:references:in-reply-to :x-enigmail-version:content-type; bh=UabiG9TFd7e9Ew2beHGnYCJzP131zYjol+9D1gof3KE=; b=Bj/sL12NM+5MZMWimt5QrhPZmF5Ttr/nnJWUgzk63Ci7mUSI0TuDkcPb88lKWFC5a+ VLVbi3XBlfnyEhGAUF4zjp/D9lfnR2f1rq4Oo7umcuehsb222GH6n4QJVrgU7OghuvKH lKrccIHWccNw2GXZn3SWJpl9kT3CjbfMxLCVw= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:subject:references :in-reply-to:x-enigmail-version:content-type; b=PauwkrlAHYNqc6e1kyldxn4AYc5A7DqG0QdPcA+s9WhqyfFD47lDgIroRzxreF41o6 Eu8v/Pu9XAz0eCjbYQhko+5ZkcVMNyeGU/Ok60c/4k/BTrR9Uf3gBBR8ZZR2gLVjUlhq 8SI0rI4uo0hiU9CV/SDJpi+h9a0vGrU2j4sCY= Received: by 10.227.129.17 with SMTP id m17mr1095635wbs.79.1294418401338; Fri, 07 Jan 2011 08:40:01 -0800 (PST) Received: from debian.bg45.phnet (114-230.203-62.cust.bluewin.ch [62.203.230.114]) by mx.google.com with ESMTPS id q18sm17811829wbe.23.2011.01.07.08.39.59 (version=TLSv1/SSLv3 cipher=RC4-MD5); Fri, 07 Jan 2011 08:40:00 -0800 (PST) Message-ID: <4D2741D4.3050903@gmail.com> Date: Fri, 07 Jan 2011 17:39:48 +0100 From: =?UTF-8?B?VmxhZGltaXIgJ8+GLWNvZGVyL3BoY29kZXInIFNlcmJpbmVua28=?= User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.16) Gecko/20101226 Icedove/3.0.11 MIME-Version: 1.0 To: grub-devel@gnu.org References: <4D26DE69.5080106@gmail.com> <4D26EB2E.5030106@gmail.com> <4D26F7C6.9080904@gmail.com> <4D270506.9060003@gmail.com> <4D2720CC.8030207@gmail.com> In-Reply-To: <4D2720CC.8030207@gmail.com> X-Enigmail-Version: 1.0.1 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="------------enig947D000E9050F28F235ED612" X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.6 (newer, 2) Subject: Re: Reserved first sector for UFS X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GNU GRUB List-Id: The development of GNU GRUB List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 07 Jan 2011 17:44:56 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig947D000E9050F28F235ED612 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 01/07/2011 03:18 PM, Gr=C3=A9goire Sutre wrote: > On 01/07/2011 13:20, Vladimir '=CF=86-coder/phcoder' Serbinenko wrote: > >>> Do you know of any OS that would put the superblock in sector 0? >>> I googled a bit, but I couldn't find examples where UFS would >>> not start with a boot sector (afaics, it usually starts with a >>> bootblock area of at least 8KiB -- with OS-specific data in it, >>> e.g. a disklabel). >>> >> According to *BSD http://fxr.watson.org/fxr/source/ufs/ffs/fs.h: >> >> */"* Depending on the architecture and the media, the superblock may/*= >> */* reside in any one of four places. For tiny media where every >> block /* >> */* counts, it is placed at the very front of the partition. >> Historically,/* >> */* UFS1 placed it 8K from the front to leave room for the disk label >> and/* >> */* a small bootstrap. For UFS2 it got moved to 64K from the front to >> leave/* >> */* room for the disk label and a bigger bootstrap, and for really >> piggy/* >> */* systems we check at 256K from the front if the first three fail/*"= > > Interesting. So, when searching for a UFS superblock, sector 0 is a > candidate (after sectors 128 and 16). It seems to me that this use of > sector 0 for tiny media does not apply to (recent) NetBSD newfs(8), > though. > > If we want to improve the situation, we could let the filesystem driver= > dynamically decide whether the first sector is reserved or not. But > I'm not sure that it's worth it (the first sector of a partition > containing a filesystem is only used for blocklist embedding, right?). > It's used for putting boot.img into partition. But you're right, it's used mainly for blocklists installs. > Gr=C3=A9goire > > _______________________________________________ > Grub-devel mailing list > Grub-devel@gnu.org > http://lists.gnu.org/mailman/listinfo/grub-devel > --=20 Regards Vladimir '=CF=86-coder/phcoder' Serbinenko --------------enig947D000E9050F28F235ED612 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iF4EAREKAAYFAk0nQdQACgkQNak7dOguQgkFTAEAjQ1fgb4hxbXt9GyfWZzPv0G2 BKFBFiyp5ZLYyvQoZuEBAKA/LQCLeWmmF9jm5OYXE91nE873eIfVLPzxAW2m3XCJ =YtqV -----END PGP SIGNATURE----- --------------enig947D000E9050F28F235ED612--