How do I calculate UPAGES?

[dbj at RICE.ARPA]

From:  Dave Johnson <dbj at RICE.ARPA>

UPAGES is the sizeof a struct user plus whatever amount of space you
want or need to have available for the kernel stack.  UPAGES is in units
of NBPG bytes, which is defined to be 512 under both 4.2 and 4.1.
Under 4.2, the user structure is 1904 bytes long, and UPAGES is defined
to be 8.  Back under 4.1, the user structure was only 1172 bytes long,
but UPAGES was also defined to be 8 so there was more kernel stack space
available under 4.1 than 4.2.  Interesting...

                                        Dave Johnson
                                        Dept. of Computer Science
                                        Rice University
                                        dbj at rice.ARPA