Memory management

[Julian Stecklina]

Hello,

let's say in my rootserver I need a contiguous block of memory 1 MB in
size. I would request this memory from Sigma0 via L4_Sigma0_GetAny and
get a single Flexpage of this size. 
In order to implement a fine-grained write-barrier on parts of this
memory block, I need to make individual pages of this block read-only.
As I understand it, the privileged system call MemoryControl provides
this functionality, but:

a) it is privileged, but all my servers would need this functionality.
How is this efficiently accomplished?

b) MemoryControl seems to operate on whole fpages only. How do I split
a flexpage?

Regards,
-- 
Julian Stecklina

"We were not out to win over the Lisp programmers; we were after the
C++ programmers. We managed to drag a lot of them about halfway to
Lisp." - Guy Steele, Java spec co-author