From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from sc8-sf-mx1-b.sourceforge.net ([10.3.1.11] helo=sc8-sf-mx1.sourceforge.net) by sc8-sf-list1.sourceforge.net with esmtp (Cipher TLSv1:DES-CBC3-SHA:168) (Exim 3.31-VA-mm2 #1 (Debian)) id 1AGODl-00062J-00 for ; Sun, 02 Nov 2003 11:49:09 -0800 Received: from m17.lax.untd.com ([64.136.30.80]) by sc8-sf-mx1.sourceforge.net with smtp (Exim 4.24) id 1AGODl-00015s-0F for user-mode-linux-devel@lists.sourceforge.net; Sun, 02 Nov 2003 11:49:09 -0800 Subject: Re:[uml-devel] Partitioning scheme for ubd's Message-ID: <20031102.111506.-2022799.0.mcmechanjw@juno.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: James W McMechan Sender: user-mode-linux-devel-admin@lists.sourceforge.net Errors-To: user-mode-linux-devel-admin@lists.sourceforge.net List-Help: List-Post: List-Subscribe: , List-Id: The user-mode Linux development list List-Unsubscribe: , List-Archive: Date: Sun, 2 Nov 2003 11:15:01 -0800 To: blaisorblade_spam@yahoo.it Cc: user-mode-linux-devel@lists.sourceforge.net 1) well the device names are at least internally consistent. and there are some devices like blah0p1 already. also the proposed scheme for dealing with devices above 26 is currently a mess, hdaa hdaaa, since with the last patch set I was using I had 400 disks mounted... mounting /dev/ubdpa1 ick... we only need one disk controller for a effectively unlimited of disk drives which could be called c0dXpY if desired... I don't know of any easy way to generate base26[a-z] numbers from normal numbers. So we might want to instead use ubd0p1 see cpqarray.txt ciss.txt in /usr/src/linux/Documentation 2) Yes loop mounting a partitioned device is a pain see however the offset option to the loop device e.g. mount -oloop,offset=16384 partitioned_fs /mnt/loop will mount the first partition the calculation is based on the default geometry 512 byte/sector 32 sectors/track 128 heads/cylinder and the first partition is at C0T1S0 1 track in from start so 512 * 32 = 16384 DOS partitions are a pain... 2nd and later are usually at CXT0S0 cylinder X which has offset $(( 512 * 32 * 128 * X )) 2097152 is not a handy number and the X is 1 less then the start address shown in fdisk fdisk's expert mode "x" shows the correct number in the cylinder column 3) you could combine several ubd into one device in theory, the device mapper might work for this and a plugin to do this through the partition code should be possible but I would expect a mess, you would have to use the device tree to find all the ubd's and merge them into a single device and then based on which partition you want to use map back to the real ubd devices, so it should be possible but messy. ________________________________________________________________ The best thing to hit the internet in years - Juno SpeedBand! Surf the web up to FIVE TIMES FASTER! Only $14.95/ month - visit www.juno.com to sign up today! ------------------------------------------------------- This SF.net email is sponsored by: SF.net Giveback Program. Does SourceForge.net help you be more productive? Does it help you create better code? SHARE THE LOVE, and help us help YOU! Click Here: http://sourceforge.net/donate/ _______________________________________________ User-mode-linux-devel mailing list User-mode-linux-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/user-mode-linux-devel