108 lines
2.9 KiB
Plaintext
108 lines
2.9 KiB
Plaintext
WARNING
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=======
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The default loop device major number has changed from 12 to 28. Please make
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sure your old /dev/loop* devices are removed and new ones created as shown
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below.
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Loop devices, version 3.3
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=======================
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The modularized loop device may be installed at a block device of your
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choice without recompilation (see NEWS file). I added this because the loop
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device is not officially registered and it would be nice to easily reload it
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on another device if the major gets allocted.
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Loop devices, version 2
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=======================
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Loop devices can be used to mount regular files, to put more than one
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file system on a disk partition and to provide transparent data
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encryption.
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Note: This implementation differs from my old loop devices that are
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also found in some distributions of SLS.
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All this code is covered by the General Public License.
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Creating loop devices
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---------------------
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Create the device entries in /dev:
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for n in 0 1 2 3 4 5 6 7; do mknod /dev/loop$n b 28 $n; done
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Installation
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------------
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Do one of the following depending on whether the loadable modules
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or a kernel patch are required. However because the block driver symbols
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are not in the kernel syms, even the loadable driver requires that a small
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patch be applied to your kernel source.
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Applying the Kernel patch
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-------------------------
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Apply the kernel patch to your 1.1.16 kernel source:
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(cd /usr/src/linux; patch -s) < patches/lo.patch
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Patch for the Loadable driver
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-----------------------------
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Apply the ksyms patch to your 1.1.16 kernel source:
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If you are using a kernel prior to version 1.1.23 then do:
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(cd /usr/src/linux; patch -s) < module/lo.patch-pre-1.1.23
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otherwise for the new module code, use
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(cd /usr/src/linux; patch -s) < module/lo.patch
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In the latter case you MUST also have the new module utilities (insmod, rmmod
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etc..) from nic.funet.fi /pub/OS/Linux/PEOPLE/Linus/v1.1
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DES Encryption
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--------------
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If you want to use DES encryption, download the DES module and add it:
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cd /usr/src/linux
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tar xvfz des.1.tar.gz
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touch include/linux/des.h kernel/des.c
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Rebuild the kernel:
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-------------------
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make depend
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make # or something like that
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The loop.o module:
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------------------
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If you decide to use the loop loadable module you need to compile the object:
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cd module
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make
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Migration
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---------
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Version 1 (and later) of the loop devices uses a slightly different wrapper
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algorithm for DES than version 0. In the unlikely event that you have some
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old ecrypted files, you have to convert them with the (untested) utility
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cvdes before they can be used with version 1 and later. (See the man page
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for details.)
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Usage
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-----
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Is documented in the accompanying losetup man page.
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Authors
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-------
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Original author: Theodore Ts'o <tytso@athena.mit.edu>
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Maintainer: Werner Almesberger <almesber@bernina.ethz.ch>
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DES author: Eric Young <eay@psych.psy.uq.oz.au>
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Modularized and updated 28-5-94: Mitch DSouza <m.dsouza@mrc-apu.cam.ac.uk>
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