L4 SystemCall for Address Space

------> PageNo
1. address >> 10 : 1024bytes 단위의 index
2. page size의 배수.

------> FPage

------> SpaceControl

------> MAP Control

1. configuration a virtual address space.
2. creating and removing mappings of virtual page to physical page.

typedef union {
 L4_Word_t raw;
 L4_Word_t space_no;
} L4_SpaceId_t;

#define L4_nilspace L4_SpaceId(~0UL)

L4_INLINE L4_SpaceId_t
L4_SpaceId(L4_Word_t space_no)
{
 L4_SpaceId_t s = { 0UL };
 s.space_no = space_no;
 return s;
}