61 lines · plain
1.. SPDX-License-Identifier: GPL-2.02 3========================4BFS Filesystem for Linux5========================6 7The BFS filesystem is used by SCO UnixWare OS for the /stand slice, which8usually contains the kernel image and a few other files required for the9boot process.10 11In order to access /stand partition under Linux you obviously need to12know the partition number and the kernel must support UnixWare disk slices13(CONFIG_UNIXWARE_DISKLABEL config option). However BFS support does not14depend on having UnixWare disklabel support because one can also mount15BFS filesystem via loopback::16 17 # losetup /dev/loop0 stand.img18 # mount -t bfs /dev/loop0 /mnt/stand19 20where stand.img is a file containing the image of BFS filesystem.21When you have finished using it and umounted you need to also deallocate22/dev/loop0 device by::23 24 # losetup -d /dev/loop025 26You can simplify mounting by just typing::27 28 # mount -t bfs -o loop stand.img /mnt/stand29 30this will allocate the first available loopback device (and load loop.o31kernel module if necessary) automatically. If the loopback driver is not32loaded automatically, make sure that you have compiled the module and33that modprobe is functioning. Beware that umount will not deallocate34/dev/loopN device if /etc/mtab file on your system is a symbolic link to35/proc/mounts. You will need to do it manually using "-d" switch of36losetup(8). Read losetup(8) manpage for more info.37 38To create the BFS image under UnixWare you need to find out first which39slice contains it. The command prtvtoc(1M) is your friend::40 41 # prtvtoc /dev/rdsk/c0b0t0d0s042 43(assuming your root disk is on target=0, lun=0, bus=0, controller=0). Then you44look for the slice with tag "STAND", which is usually slice 10. With this45information you can use dd(1) to create the BFS image::46 47 # umount /stand48 # dd if=/dev/rdsk/c0b0t0d0sa of=stand.img bs=51249 50Just in case, you can verify that you have done the right thing by checking51the magic number::52 53 # od -Ad -tx4 stand.img | more54 55The first 4 bytes should be 0x1badface.56 57If you have any patches, questions or suggestions regarding this BFS58implementation please contact the author:59 60Tigran Aivazian <aivazian.tigran@gmail.com>61