Commit Graph

2 Commits

Author SHA1 Message Date
Bruce Evans
9c9755b4f8 Fixed warnings for pointer versus int type mismatches. Addresses must
be converted to fixed-sized integers when they are passed across the
binary interface to the kernel.

Didn't fix rotted bits (including not passing dosdev to the kernel and
serious out of dateness when initially committed).
1998-10-10 13:51:24 +00:00
Joerg Wunsch
c38b4f3b91 (Part #2, after the Internet link broke totally yesterday.)
This is the long-threatened ISO 9660 CD-ROM bootstrap code.

This work has been sponsored by Plutotech International, Inc (who paid
the initial work), and interface business GmbH (where i did most of
the work).  A big thanks also goes to Bruce Evans, for his continuing
help and answering my stupid questions.

The code is basically functioning, with the following caveats:

. Rock Ridge attributes are not yet supported.
. Only SCSI CD-ROMs are supported, since i fail to see any possibility
  to determine the drive type using BIOS functions.  (Even for hard disks,
  this determination is done by a big hack only.)
. El Torito specifies a lot of crap and useless misfeatures, but crucial
  things like the ability to figure out the CD TOC have been ``forgotten''.
  Thus, if you wanna boot a multisession CD, you need to know at which CD
  block your session starts, and need to speciffy it using the @ clause.

. None of the CD-ROM controllers i've seen so far implements the full
  El Torito specification at all.  Adaptec is probably the closest, but
  they miss on non-emulation booting (which would be the most logical
  choice for us).  Thus, the current code bloats the 7.5 KB boot code
  up to 1.44 MB, in order to fake a `floppy' image.

  If you wanna use it, specify this file as the boot image on the
  command-line of the mksiosfs command (option -b).

  Caveat emptor: some versions of the Adaptec BIOS might even fail to
  access the CD-ROM at all, using the BIOS functions.  I think i've
  notice this for ver 1.26, the code has been tested with ver 1.23.

The boot string is as follows:

        [@sess-start] [filename] [-flags]

sess-start      Extend # where the last session starts, measured in
                CD-ROM blocks.

filename        As usual, but the input is case-insensitive by now
                (since we  don't grok RR anyway).

flags           As usual, but -C (use CDROM root f/s) is default, so
                specifying -C will decactivate this option (which is
                probably not what you want :).

A lot of cleanup work is probably required, and some of the files
could/should be merged back to biosboot, perhaps made conditional on
some #ifdef.  The malloc implementation that comes with cdboot might
also be useful for kzipboot.  (I needed a malloc() since the root dir
ain't fixed in size on a CD.)

I've been testing all this with a 2.2-STABLE as the base for biosboot.
I don't expect too many surprises, although i know the biosboot stuff
has been changed a lot in -current lately.  I'm sure Bruce will
comment on all this here anyway. :-)
1997-07-11 05:52:41 +00:00