Change a boundary check to ensure that we won't accidentally read and use
uninitialized memory if ATA_RAID_TYPE_MAX is updated without updating the
array.
Update comment near ATA_RAID_TYPE_MAX to note that the array in ata_raid.c
should be updated if a new ATA_RAID_TYPE_* is added.
Such RAID controllers are actually just IDE controllers with a BIOS that
can create RAID volumes and write the configuration info to config blocks
on the disks. The BIOS can do I/O to these volumes, and the OS must
understand the config blocks and implement RAID in software in order to be
able to use these volumes.
Only SPAN (simple concatenation) and RAID0 are supported at this time,
and writing back config blocks is also not supported at this time. Currently,
only the Promise configuration scheme is supported, although supporting
the Highpoint scheme should not be too difficult.
In any case, this is sufficient to use the Promise RAID0 volume (thus
preserving the win2k AS installation) on this new Intel server I have.
Thanks to Soren Schmidt for doing the work in FreeBSD; it made this
task much easier. The config block parsing code is adapted from his
work.