__HPCMIPS_MAXDISKS
#define DISKUNIT(dev) ((minor(dev) / OLDMAXPARTITIONS) % __HPCMIPS_MAXDISKS)
((minor(dev) / (__HPCMIPS_MAXDISKS * OLDMAXPARTITIONS)) * OLDMAXPARTITIONS))
((part) / OLDMAXPARTITIONS) * (__HPCMIPS_MAXDISKS * OLDMAXPARTITIONS))