| BFS FILESYSTEM FOR LINUX |
| ======================== |
| |
| The BFS filesystem is used by SCO UnixWare OS for the /stand slice, which |
| usually contains the kernel image and a few other files required for the |
| boot process. |
| |
| In order to access /stand partition under Linux you obviously need to |
| know the partition number and the kernel must support UnixWare disk slices |
| (CONFIG_UNIXWARE_DISKLABEL config option). However BFS support does not |
| depend on having UnixWare disklabel support because one can also mount |
| BFS filesystem via loopback: |
| |
| # losetup /dev/loop0 stand.img |
| # mount -t bfs /dev/loop0 /mnt/stand |
| |
| where stand.img is a file containing the image of BFS filesystem. |
| When you have finished using it and umounted you need to also deallocate |
| /dev/loop0 device by: |
| |
| # losetup -d /dev/loop0 |
| |
| You can simplify mounting by just typing: |
| |
| # mount -t bfs -o loop stand.img /mnt/stand |
| |
| this will allocate the first available loopback device (and load loop.o |
| kernel module if necessary) automatically. If the loopback driver is not |
| loaded automatically, make sure that your kernel is compiled with kmod |
| support (CONFIG_KMOD) enabled. Beware that umount will not |
| deallocate /dev/loopN device if /etc/mtab file on your system is a |
| symbolic link to /proc/mounts. You will need to do it manually using |
| "-d" switch of losetup(8). Read losetup(8) manpage for more info. |
| |
| To create the BFS image under UnixWare you need to find out first which |
| slice contains it. The command prtvtoc(1M) is your friend: |
| |
| # prtvtoc /dev/rdsk/c0b0t0d0s0 |
| |
| (assuming your root disk is on target=0, lun=0, bus=0, controller=0). Then you |
| look for the slice with tag "STAND", which is usually slice 10. With this |
| information you can use dd(1) to create the BFS image: |
| |
| # umount /stand |
| # dd if=/dev/rdsk/c0b0t0d0sa of=stand.img bs=512 |
| |
| Just in case, you can verify that you have done the right thing by checking |
| the magic number: |
| |
| # od -Ad -tx4 stand.img | more |
| |
| The first 4 bytes should be 0x1badface. |
| |
| If you have any patches, questions or suggestions regarding this BFS |
| implementation please contact the author: |
| |
| Tigran A. Aivazian <tigran@veritas.com> |