1.. SPDX-License-Identifier: GPL-2.0 2 3======================== 4BFS Filesystem for Linux 5======================== 6 7The BFS filesystem is used by SCO UnixWare OS for the /stand slice, which 8usually contains the kernel image and a few other files required for the 9boot process. 10 11In order to access /stand partition under Linux you obviously need to 12know the partition number and the kernel must support UnixWare disk slices 13(CONFIG_UNIXWARE_DISKLABEL config option). However BFS support does not 14depend on having UnixWare disklabel support because one can also mount 15BFS filesystem via loopback:: 16 17 # losetup /dev/loop0 stand.img 18 # mount -t bfs /dev/loop0 /mnt/stand 19 20where stand.img is a file containing the image of BFS filesystem. 21When you have finished using it and umounted you need to also deallocate 22/dev/loop0 device by:: 23 24 # losetup -d /dev/loop0 25 26You can simplify mounting by just typing:: 27 28 # mount -t bfs -o loop stand.img /mnt/stand 29 30this will allocate the first available loopback device (and load loop.o 31kernel module if necessary) automatically. If the loopback driver is not 32loaded automatically, make sure that you have compiled the module and 33that modprobe is functioning. Beware that umount will not deallocate 34/dev/loopN device if /etc/mtab file on your system is a symbolic link to 35/proc/mounts. You will need to do it manually using "-d" switch of 36losetup(8). Read losetup(8) manpage for more info. 37 38To create the BFS image under UnixWare you need to find out first which 39slice contains it. The command prtvtoc(1M) is your friend:: 40 41 # prtvtoc /dev/rdsk/c0b0t0d0s0 42 43(assuming your root disk is on target=0, lun=0, bus=0, controller=0). Then you 44look for the slice with tag "STAND", which is usually slice 10. With this 45information you can use dd(1) to create the BFS image:: 46 47 # umount /stand 48 # dd if=/dev/rdsk/c0b0t0d0sa of=stand.img bs=512 49 50Just in case, you can verify that you have done the right thing by checking 51the magic number:: 52 53 # od -Ad -tx4 stand.img | more 54 55The first 4 bytes should be 0x1badface. 56 57If you have any patches, questions or suggestions regarding this BFS 58implementation please contact the author: 59 60Tigran Aivazian <aivazian.tigran@gmail.com> 61