projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | BFS FILESYSTEM FOR LINUX |
| 2 | ======================== | |
| 3 | ||
| 4 | The BFS filesystem is used by SCO UnixWare OS for the /stand slice, which | |
| 5 | usually contains the kernel image and a few other files required for the | |
| 6 | boot process. | |
| 7 | ||
| 8 | In order to access /stand partition under Linux you obviously need to | |
| 9 | know the partition number and the kernel must support UnixWare disk slices | |
| 10 | (CONFIG_UNIXWARE_DISKLABEL config option). However BFS support does not | |
| 11 | depend on having UnixWare disklabel support because one can also mount | |
| 12 | BFS filesystem via loopback: | |
| 13 | ||
| 14 | # losetup /dev/loop0 stand.img | |
| 15 | # mount -t bfs /dev/loop0 /mnt/stand | |
| 16 | ||
| 17 | where stand.img is a file containing the image of BFS filesystem. | |
| 18 | When you have finished using it and umounted you need to also deallocate | |
| 19 | /dev/loop0 device by: | |
| 20 | ||
| 21 | # losetup -d /dev/loop0 | |
| 22 | ||
| 23 | You can simplify mounting by just typing: | |
| 24 | ||
| 25 | # mount -t bfs -o loop stand.img /mnt/stand | |
| 26 | ||
| 27 | this will allocate the first available loopback device (and load loop.o | |
| 28 | kernel module if necessary) automatically. If the loopback driver is not | |
| a81792f6 JB |
29 | loaded automatically, make sure that you have compiled the module and |
| 30 | that modprobe is functioning. Beware that umount will not deallocate | |
| 31 | /dev/loopN device if /etc/mtab file on your system is a symbolic link to | |
| 32 | /proc/mounts. You will need to do it manually using "-d" switch of | |
| 33 | losetup(8). Read losetup(8) manpage for more info. | |
| 1da177e4 LT |
34 | |
| 35 | To create the BFS image under UnixWare you need to find out first which | |
| 36 | slice contains it. The command prtvtoc(1M) is your friend: | |
| 37 | ||
| 38 | # prtvtoc /dev/rdsk/c0b0t0d0s0 | |
| 39 | ||
| 40 | (assuming your root disk is on target=0, lun=0, bus=0, controller=0). Then you | |
| 41 | look for the slice with tag "STAND", which is usually slice 10. With this | |
| 42 | information you can use dd(1) to create the BFS image: | |
| 43 | ||
| 44 | # umount /stand | |
| 45 | # dd if=/dev/rdsk/c0b0t0d0sa of=stand.img bs=512 | |
| 46 | ||
| 47 | Just in case, you can verify that you have done the right thing by checking | |
| 48 | the magic number: | |
| 49 | ||
| 50 | # od -Ad -tx4 stand.img | more | |
| 51 | ||
| 52 | The first 4 bytes should be 0x1badface. | |
| 53 | ||
| 54 | If you have any patches, questions or suggestions regarding this BFS | |
| 55 | implementation please contact the author: | |
| 56 | ||
| 69688262 | 57 | Tigran Aivazian <tigran@aivazian.fsnet.co.uk> |