Re: BFFS 1.5

[Stefan Hensen <hensen%wpos4.physik.uni-wuppertal.de@localhost>]

On 19 Jun 1998, Georges Heinesch wrote:

> According the docs, BFFS 1.5 can be used via a Mountlist (or
> DOSDriver) or via the RDB.

That's right. I have successfully used both methods.
 
> I tested both versions with the /var partition (sd0d).
> 
> 1. My DOSDriver (Filename SD0D):
> 
>    [...]
> 
>    This seems to work more or less correctly. However I don't know why
>    the FileSystem calls the first partiton BFFSa, the second BFFSb,
>    aso. Can this be controlled somewhere?

In contrast to AmigaDOS filesystems, there exist no volume names on unix
filesystems (they are not needed for unix(-like) systems, because you have
the directory names of the mountpoints in the filesystem tree instead).
So the author had to "invent" some way to generate volume names for unix
filesystems on the AmigaDOS side automatically and he called them 'BFFSa',
'BFFSb' and so on.
AFAIK, there is no way to change these names, but you can choose some more
meaningful device/unit names. For example, I used 'BSDROOT:' and 'BSDUSR:'
as device names for NetBSD's '/' and '/usr' partitions in my mountlist,
DOSDrivers or RDB entries, respectively.

>    ----- cut here -----
>    Mounted disks:
>    Unit      Size    Used    Free Full Errs   Status   Name
>    BFFS:      19M     657   19168   3%   0  Read/Write BFFSa
>    ----- cut here -----

I wonder why the unit name appears here as 'BFFS:', if you called your
DOSDrivers file 'SD0D' ...

On my system (using the above mentioned names in mountlist or RDB), the
corresponding lines look like this:
   Mounted disks:
   Unit      Size    Used    Free Full Errs   Status   Name
   BSDROOT:   48M   16731   33312  33%   0  Read/Write BFFSa
   BSDUSR:   897M  674565  244440  73%   0  Read/Write BFFSb

>    After thorough study of the docs, I didn't quite get what the
>    PreAlloc Keyword is for.

This field can be used to set certain options of the filesystem concerning
things like handling of symbolic links, case sensitivity in file names,
mapping of protection bits for group and other, read-omly mode etc.. It is
recommended to use BFFStool (included in BFFS 1.5) to test these options
and finally insert in the mountlist the PreAlloc value displayed by that
program.

>    Besides this, the BFFSFileSystem behaves somewhat strange when it
>    comes to mounting. "mount SD0D:" doesn't trigger the partition icon
>    to appear immediately. First, an access to this partition has to be
>    done. Then it appears. ACTIVATE=1 is set in the DOSDriver and the
>    DOSDriver icon tooltype.

When the RDB method (see below) is used, the icons appear automatically
after a few seconds.

> 2. The RDB method created a real problem. The partition wasn't
>    readable any more by NetBSD. The BFFS docs state that the
>    identifier should be set to 0x42464653 (BFFS).

This is only a recommendation (in case you have no other requirements or
preferences). But in principle, you can use here any identifier you like
(or need), as long as it does not conflict with other filesystem types.

>    The NetBSD INSTALL docs crealry say that the identifier must be set
>    to 0x4e425507.

This is really a requirement.

>    This contradicts with the BFFS docs.
> 
>    ----- cut here -----
>    Select the "Custom File System" button and fill in the "Identifier
>    =" field. I recommend the value 0x42464653 ('BFFS'), but you can
>    use and filesystem type you want.                        ^^^^^^^
     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
As said above.

>    The NetBSD people are partial to
>    'BSDx' - where x would be 'R', 'S', 'D', 'E', 'F', 'G', 'H', etc
>    depending on how NetBSD is using the partition.

This is incorrect.
I don't know if it worked this way with some very early version of NetBSD
or with disks from some other platform (it seems that BFFS was originally
written for disks from Sun systems), but with partitions from NetBSD/Amiga
you have to use the identifiers from the INSTALL docs.

>    The disadvantage to
>    this scheme is that for every UNIQUE file system Identifier you
>    want to mount as a BFFS filesystem, you have to add the BFFS
>    filesystem to the RDB with that Identifier.
>    ----- cut here -----

If you want to mount NetBSD root partitions as well as other partitions
with BFFS, you have to install the BFFS filesystem twice in the RDB:

1.) with identifier 0x4e425207 ('NBR\07') for the root partition
2.) with identifier 0x4e425507 ('NBU\07') for all other partitions
 
>    Is there anybody who is using this method with the RDB to access
>    NetBSD from AmigaOS?

For me, it works in the above described way without problems.

Regards,

Stefan Hensen

----------------------------------------------------------
Stefan Hensen
e-mail: hensen%wpos4.physik.uni-wuppertal.de@localhost