This is hopefully the last time in a while that
something in the mm subsystem needs a refactor
this large. There are two main changes:
- The page frame allocator returns a vm_page_t
rather than a virtual address.
- Data for the slab allocator is now stored in
struct vm_page, which means there is no overhead
in the slab itself so the space is used in a
more efficient manner.
This is a huge commit, but it mainly just moves
some files around and doesn't change their
contents much.
A lot of stuff works the same on amd64 as it does
on i386, so i'm moving the parts that are specific
to the latter into separate subdirectories while
the rest can be shared with the amd64 codebase.