HEADS up on HEAD

[Matthew Dillon]

    Note that due to recent changes in HEAD, people using HEAD need to
    rebuild and reinstall the kernel AND world AND do a make upgrade to
    deal with device minor number changes that have occured.

    devices will only be partially compatible with 1.8. e.g devices like
    /dev/ad6s1a haven't changed, but raw devices like /dev/ad6 and /dev/ad6s1
    have changed.  HEAD will no longer accept opens using the old devices.

    The ATA CD driver (not NATA yet) now supports devices corresponding to
    audio CD tracks via /dev/acd0t1 /dev/acd0t2, etc... MAKEDEV acd0t will
    generate the devices needed.  This isn't well tested.

    I've almost got the disklabel disentangled.  All the logic sequencing
    is in place... that is, making sure the disk management layer doesn't
    try to interpret the MBR or a disklabel until someone actually tries
    to access something needing the MBR or a disklabel.  The maximum number
    of slices has been increased to 128 and the maximum number of partitions
    has been increased to 256.

    I still have a few more hard coded constants to disentangle and then
    I'll be able to work on a pluggable kernel API for slice and label
    management.

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>