In sureg:
	If this process does not have a context:
		If the LRU context belongs to a process:
			Indicate that the process has no context.
			Make the process MRU of the no context list.
		Take the LRU context.
		Mark the context invalid.
	Make this context MRU.
	Make this process MRU on the have context list.
	Switch to the new context.
	While there are insufficient page maps:
		If there is a free page map:
			Take the page map.
		Else if there are processes on the no context list:
			Take the last page map from the LRU process.
			If the LRU process has no more page maps:
				Remove the process from the no context list.
		Else if there are processes on the have context list:
			Take the last page map from the LRU process.
			If the LRU process has no more page maps:
				Remove the process from the have context list.
	Map all page maps which are not already mapped.
	Map all page table entries which are not already mapped.
