Int 31 Fn FF1E  P - Causeway - "unlockmem32" - Unlock Region Of Memory (3  [E]

   AX = FF1Eh
   ESI = starting linear address
   ECX = size of region in bytes

Return: CF clear if successful
   CF set on error
Desc:  allow memory to be swapped out by the virtual memory manager

Note:  locks are applied on 4K page boundaries, so memory above and below
     the specified region may be unlocked as well

See Also: AX=FF1Ch,AX=FF1Dh,AX=FF20h