Kernel: Add barebones per process virtual addresses

We now assign every (userspace) process its own MMU which we load
in scheduler. This allows every process to have separate virtual
address space.

This is very hackish implementations but it works for now

kernel/include/kernel/Memory/MMU.h

@@ -17,7 +17,7 @@ public:
 	using paddr_t = uintptr_t;
 
 public:
-	static void intialize();
+	static void initialize();
 	static MMU& get();
 
 	MMU();
@@ -31,6 +31,11 @@ public:
 
 	void map_page_at(paddr_t, vaddr_t, uint8_t);
 
+	void load();
+
+private:
+	void initialize_kernel();
+
 private:
 	uint64_t* m_highest_paging_struct;
 };

kernel/include/kernel/Process.h

@@ -4,6 +4,7 @@
 #include <BAN/StringView.h>
 #include <BAN/Vector.h>
 #include <kernel/FS/Inode.h>
+#include <kernel/Memory/MMU.h>
 #include <kernel/SpinLock.h>
 #include <kernel/Terminal/TTY.h>
 #include <kernel/Thread.h>
@@ -54,6 +55,8 @@ namespace Kernel
 
 		static Process& current() { return Thread::current().process(); }
 
+		MMU& mmu() { return m_mmu ? *m_mmu : MMU::get(); }
+
 	private:
 		Process(pid_t);
 		static Process* create_process();
@@ -81,6 +84,7 @@ namespace Kernel
 		BAN::String m_working_directory;
 		BAN::Vector<Thread*> m_threads;
 
+		MMU* m_mmu { nullptr };
 		TTY* m_tty { nullptr };
 	};
 

kernel/include/kernel/Thread.h

@@ -47,6 +47,7 @@ namespace Kernel
 
 		static Thread& current() ;
 		Process& process();
+		bool has_process() const { return m_process; }
 
 	private:
 		Thread(pid_t tid, Process*);