MAXPARTITIONSUNIT
#define FDUNIT(dev) ((minor(dev) / MAXPARTITIONSUNIT) / 8)
#define FDTYPE(dev) ((minor(dev) / MAXPARTITIONSUNIT) % 8)
#define FDPART(dev) (minor(dev) % MAXPARTITIONSUNIT)
#define FDUNIT(dev) ((minor(dev) / MAXPARTITIONSUNIT) / 8)
#define FDTYPE(dev) ((minor(dev) / MAXPARTITIONSUNIT) % 8)
#define FDPART(dev) (minor(dev) % MAXPARTITIONSUNIT)
} d_partitions[MAXPARTITIONSUNIT]; /* maximum 52 in use */
#define DISKUNIT(dev) (minor(dev) / MAXPARTITIONSUNIT)
#define DISKPART(dev) (minor(dev) % MAXPARTITIONSUNIT)
(((unit) * MAXPARTITIONSUNIT) + (part))