function removes the range of addresses between
from the physical map
is less than
then the result is undefined.
It is assumed that both
are page-aligned addresses.
removes the physical page
from all physical maps in which it resides, and reflects back the modify
bits to the appropriate pager.
function removes all user pages from the physical map
This function is called when a process exits to run down its address space
more quickly than would be the case for calling