Problems using DVD-RAM on 1.4.1

["George Harvey" <fr30%dial.pipex.com@localhost>]

I have an Amiga 2000 with a Blizzard 2060 card running NetBSD 1.4.1.
I am trying to use a Panasonic LF-D101 DVD-RAM drive as a backup
device but I'm having problems creating and mounting a filesystem.
I have partitioned the media using HDToolBox and created a BSD
partition as normal (see disklabel output at the end of this message).

The first problem is that when NetBSD creates the disklabel from the
RDB, it appears to always use a fragment size of 1024 and a block size
of 8192. If I try and newfs the disk, I get an error:
    "fragment size 1024 is too small, minimum is 2048"
I can see that the fragment size probably shouldn't be smaller than
the sector size (2048 bytes) so I put a small hack into
readdisklabel() in amiga/disksubr.c to change the sizes to 2048 and
16384. I could then create a filesystem with newfs and also check it
with fsck. But, when I try and mount it, mount complains that I have
an "incorrect super block". So my second problem is: if fsck says the
filesystem exists and is clean, why can't I mount it?


---- begin disklabel ----

# /dev/rsd1c:
type: SCSI
disk: PD-2 LF-D100
label: MDH0
flags:
bytes/sector: 2048
sectors/track: 32
tracks/cylinder: 64
sectors/cylinder: 2048
cylinders: 595
total sectors: 1218560
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0           # milliseconds
track-to-track seek: 0  # milliseconds
drivedata: 0 

5 partitions:
#        size   offset     fstype   [fsize bsize   cpg]
  c:  1218560        0     unused        0     0         # (Cyl.    0 - 594)
  d:    10240     4096       ADOS     2048  2048     2   # (Cyl.    2 - 6)
  e:  1204224    14336     4.2BSD     1024  8192     0   # (Cyl.    7 - 594)

---- end disklabel ----

George Harvey
fr30%dial.pipex.com@localhost