2.2 kernel support for bootdisks

[Eric Delaunay <delaunay@lix.polytechnique.fr>]

Hello,

  I've just finished to patch bootdisks for 2.2 kernels support (sparc mainly
but could be tweaked for all architectures as well).
I hope it is backward compatible (I tried to do that at least) but could you
verify that point?


I fixed the following problems:

1. boot floppies are still based on 2.0 kernel but could provide alternate 2.2
   kernels as well.  dbootstrap is now able to handle such cases by looking
   for alternate names of rescue & drivers disks:
     resc1440-2.2.x.bin & drv1440-2.2.x.bin
   The same scheme could be applied for subarchitectures and/or special
   kernels.
   Note: this feature is enabled by setting up MULTI_KERNELS macro in
   dinstall.h and fiddling with setup_image_names in utilities/dinstall/main.c

2. init is always using /dev/console for 2.2 kernels whenever you boot on
   framebuffer or serial console.

3. new broken loop device detection method: 2.2 kernel allows to read from
   /dev/loopN even if the image resides on an NFS server, but in the latter
   case, it still fails to mount the device: all data read out are set to 0 :-((

4. modified serial console support for 2.2 kernel to make use of /dev/console.
   Note: a serial console still could be detected using the right ioctl
   (TIOCGSERIAL) to be able to setup a working inittab.

5. more: it segfaults on 2.2 kernel because /dev/tty is not available on the
   console.  As workaround, fallback to /dev/console if opening /dev/tty
   fails. [1]

6. stderrToTTY is not working on 2.2 kernel: I disabled it in that case.

7. TFTP+RARP+NFSROOT method: don't overwrite bin/sed & usr/bin/whiptail
   if already done by previous installation (nfs file system is persitent).


SPARC improvements:
-------------------

1. new TILO tftpboot image for sparclinux & ultralinux dual boot (based on
   2.2.1 kernel).

2. alternate 2.2.1 rescue & drivers image provided for sparclinux &
   ultralinux.

3. more: this program should rather use termio, not termios, on sparc
   architecture (the latter is broken: you need to hit 4 keys before
   processing next data).


Known bugs to fix:
------------------

1. sysvinit package: "Warning: unable to open an initial console." displayed
   at boot time using a serial console & 2.2 kernel: no boot messages showed
   up until the login prompt.

Regards.

-- 
 Eric Delaunay                 | "La guerre justifie l'existence des militaires.
 delaunay@lix.polytechnique.fr | En les supprimant." Henri Jeanson (1900-1970)