Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Fri, 27 Apr 2001 12:11:23 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Fri, 27 Apr 2001 12:11:19 -0400 Received: from hermes.sistina.com ([208.210.145.141]:12301 "HELO sistina.com") by vger.kernel.org with SMTP id ; Fri, 27 Apr 2001 12:09:16 -0400 Date: Fri, 27 Apr 2001 11:09:36 -0500 From: AJ Lewis To: Goswin Brederlow Cc: linux-kernel Subject: Re: devfs and /proc/ide/hda Message-ID: <20010427110935.C1632@sistina.com> In-Reply-To: <3A9CCA76.3E6AB93A@optushome.com.au> <20010228161023.A19929@win.tue.nl> <20010301084133.C16667@sistina.com> <87snkov3uk.fsf@mose.informatik.uni-tuebingen.de> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="CblX+4bnyfN0pR09" Content-Disposition: inline User-Agent: Mutt/1.3.15i In-Reply-To: <87snkov3uk.fsf@mose.informatik.uni-tuebingen.de>; from goswin.brederlow@student.uni-tuebingen.de on Thu, Mar 08, 2001 at 01:32:03PM +0100 Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org --CblX+4bnyfN0pR09 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Thu, Mar 08, 2001 at 01:32:03PM +0100, Goswin Brederlow wrote: > > What it should do is change based on whether devfs is mounted > > or not. It doesn't make *any* sense to have > > /dev/ide/host0/foo/bar in your /proc/partitions entries if you > > aren't mounting devfs. The /proc/partitions entry is the only > > way I know of for something like LVM to determine which devices > > to scan for Volume Groups. If you can't read /proc/partitions, > > it has to attempt to scan all block devices it recognizes, > > regardless of whether they are actually on the system or not. > > This can take several minutes. >=20 > First: >=20 > % cat /proc/partitions=20 > major minor #blocks name >=20 > 3 0 20010816 ide/host0/bus0/target0/lun0/disc > 3 1 192748 ide/host0/bus0/target0/lun0/part1 > 3 2 249007 ide/host0/bus0/target0/lun0/part2 > 3 3 1 ide/host0/bus0/target0/lun0/part3 > 3 5 289138 ide/host0/bus0/target0/lun0/part5 > 3 6 1951866 ide/host0/bus0/target0/lun0/part6 > 3 7 979933 ide/host0/bus0/target0/lun0/part7 > 3 8 16346106 ide/host0/bus0/target0/lun0/part8 > 33 0 80043264 ide/host2/bus0/target0/lun0/disc > 33 1 80035798 ide/host2/bus0/target0/lun0/part1 >=20 > So its already right. Only if devfs is mounted. That's my point. Maybe it's an corner case to have devfs compiled into the kernel, but not mounted, and so we can just ignore this, but it seems to me that /proc/partitions should reflect which /dev system is currently running. > Secondly with devfs, why not just scan all /dev/discs/? >=20 > % ls -l /dev/discs=20 > total 0 > lr-xr-xr-x 1 root root 30 Jan 1 1970 disc0 -> ../ide/h= ost0/bus0/target0/lun0/ > lr-xr-xr-x 1 root root 30 Jan 1 1970 disc1 -> ../ide/h= ost2/bus0/target0/lun0/ >=20 > Also if lvm opens all known devices by way of /dev/whatever while > scanning, it will only find existing devices there with devfs. Yeah, as long as devfs is running, that makes sense. --=20 AJ Lewis Sistina Software Inc. Voice: 612-379-3951 1313 5th St SE, Suite 111 Fax: 612-379-3952 Minneapolis, MN 55414 E-Mail: lewis@sistina.com http://www.sistina.com Current GPG fingerprint =3D 3B5F 6011 5216 76A5 2F6B 52A0 941E 1261 0029 2= 648 Get my key at: http://www.sistina.com/~lewis/gpgkey (Unfortunately, the PKS-type keyservers do not work with multiple sub-keys) -----Begin Obligatory Humorous Quote---------------------------------------- A computer without a Microsoft operating system is like a dog without bricks tied to its head. -----End Obligatory Humorous Quote------------------------------------------ --CblX+4bnyfN0pR09 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (GNU/Linux) Comment: For info see http://www.gnupg.org iD8DBQE66Zm/pE6/iGtdjLERAhIBAJ9ldJzoY7neqxrtrbgx5ep9Gu1dagCeLV05 27QS3Vk3PizGYO8hIzNxv58= =RkNM -----END PGP SIGNATURE----- --CblX+4bnyfN0pR09-- - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/