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