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/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

// end is defined in the linker script.
extern u32int end;
u32int placement_address = (u32int)&end;

// Page direcory 'Just need some free memory (4kb) that is aligned (can be divided by: 4096 without a remainder).' 0x9C000
unsigned long *page_directory = (unsigned long *) 0x9C000;

// Page Table the page table comes right after the page directory
unsigned long *page_table = (unsigned long *) 0x9D000;

// Address holds the physical address of where a page is
unsigned long address=0; 

// I is a basic counting variable for our loops
unsigned int i;

/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////

// Maps the first table, then sets up other basic requirements
void MapFirstTable()
{

putshex(placement_address);

// Map the first 4MB of memory
for(i=0; i<1024; i++)
{
	page_table[i] = address | 3; // attribute set to: supervisor level, read/write, present(011 in binary)
	address = address + 4096; // 4096 = 4kb
};


// fill the first entry of the page directory
page_directory[0] = page_table; // attribute set to: supervisor level, read/write, present(011 in binary)
page_directory[0] = page_directory[0] | 3;

for(i=1; i<1024; i++)
{
	page_directory[i] = 0 | 2; // attribute set to: supervisor level, read/write, not present(010 in binary)
};

// write_cr3, read_cr3, write_cr0, and read_cr0 all come from the assembly functions
write_cr3(page_directory); // put that page directory address into CR3
write_cr0((unsigned long)read_cr0() | 0x80000000); // set the paging bit in CR0 to 1

// PAGING IS ENABLED
}