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//prototypes
void paging_install();

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#include <Paging.h>
#include <Printing.h>

unsigned int *page_directory;
unsigned int *page_table;

extern int __KERNEL_END;
extern void enablePaging();


void paging_install()
{
  //the paging directory is just behind the kernel
  page_directory = (unsigned int *) __KERNEL_END;
  
  //the first paging directory (this means for the first 4mb for memory) is right behind the paging directory
  page_table = (unsigned int *) __KERNEL_END + 0x01000;
  
  //now we fill the table
  int i;
  int adress = 0;
  for(i = 0; i < 1024; i++)
  {
    page_table[i] = adress | 3; //Attributes: supervisor, read/write, present
    adress += 0x01000;       //0x01000 = 4096 = 4kb
  }
  
  //at the table to the directory
  page_directory[0] = (int)page_table;
  page_directory[0] |= 3; //Attributes: supervisor, read/write, present
  
  //fill the rest of the tables in the directory with non-present flags
  for(i = 0; i < 1024; i++)
  {
    page_directory[0] = 0 | 2; //Attributes: supervisor, read/write, not present
  }
  
  //
  //finally enable and start paging
  //
  
  //load the page directory pointer
  __asm__ __volatile__("mov %0, %%cr3":: "b"(page_directory));
  
  //now start it!
  //enablePaging();
}

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[global _enablePaging]
_enablePaging:
  mov eax, cr0
  or eax, 0x80000000
  mov cr0, eax

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OUTPUT_FORMAT("binary")
ENTRY(start)
phys = 0x00100000;
SECTIONS
{
  .text phys : AT(phys) {
    code = .;
    *(.text)
    . = ALIGN(4096);
  }
  .data : AT(phys + (data - code))
  {
    data = .;
    *(.data)
    . = ALIGN(4096);
  }
  .bss : AT(phys + (bss - code))
  {
    bss = .;
    *(.bss)
    . = ALIGN(4096);
  }
  end = .;_end = .;__end = .;___KERNEL_END = .;
}

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page_directory = (unsigned int *) __KERNEL_END;
 
  //the first paging directory (this means for the first 4mb for memory) is right behind the paging directory
  page_table = (unsigned int *) __KERNEL_END + 0x01000;

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//fill the rest of the tables in the directory with non-present flags
  for(i = 0; i < 1024; i++)
  {
    page_directory[0] = 0 | 2; //Attributes: supervisor, read/write, not present
  }

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unsigned int *page_directory;
unsigned int *page_table;

extern int __KERNEL_END;
extern void enablePaging();


void paging_install()
{
  [b]int temp = (__KERNEL_END + 0X0fff) & 0x0fffff000;
  //the paging directory is just behind the kernel
  page_directory = (unsigned int *) temp;
  
  //the first paging directory (this means for the first 4mb for memory) is right behind the paging directory
  page_table = (unsigned int *) temp + 0x01000;[/b]
  
  //now we fill the table
  int i;
  int adress = 0;
  for(i = 0; i < 1024; i++)
  {
    page_table[i] = adress | 3; //Attributes: supervisor, read/write, present
    adress += 0x01000;       //0x01000 = 4096 = 4kb
  }
  
  //at the table to the directory
  page_directory[0] = (int)page_table;
  page_directory[0] |= 3; //Attributes: supervisor, read/write, present
  
  //fill the rest of the tables in the directory with non-present flags
  for([b]i = 1[/b]; i < 1024; i++)
  {
    page_directory[0] = 0 | 2; //Attributes: supervisor, read/write, not present
  }
  
  //
  //finally enable and start paging
  //
  
  //load the page directory pointer
  __asm__ __volatile__("mov %0, %%cr3":: "b"(page_directory));
  
  //now start it!
  enablePaging();
}

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  //fill the rest of the tables in the directory with non-present flags
  for([b]i = 1[/b]; i < 1024; i++)
  {
    page_directory[0] = 0 | 2; //Attributes: supervisor, read/write, not present
  }