OSDev.org

Code: Select all

#include "inc/page.h"
#include "inc/phmman.h"
#include "inc/video.h"
#include "inc/system.h"
/**********************/
dir_t *kdir=0,*cdir=0;
/**********************/
void load(uint *dir)
{   uint cr0;
    asm volatile("mov %0, %%cr3":: "r"(dir));
    asm volatile("mov %%cr0, %0": "=r"(cr0));
    cr0 |= 0x80000000;
    asm volatile("mov %0, %%cr0":: "r"(cr0));
}
void vmem::alloc(uint add,int pre,int rw,int us)
{
    video v;
    phmman phm;  // phiscal memory manger
    int page = add / 0x1000;
    int table= page/ 1024;
    if(kdir->tables[table].pre==1)
    {
        page_t *otable = (page_t *)kdir->tables[table].add;
        if(otable->pages[page].pre == 1)
        {return;
        }else{
            otable->pages[page].pre = pre;
            otable->pages[page].r_w = rw;
            otable->pages[page].u_s = us;
            otable->pages[page].add = add;
        }
    }else{
       page_t *ntable = (page_t *)phm.allocpg();
       kdir->tables[table].pre = pre;
       kdir->tables[table].r_w = rw;
       kdir->tables[table].u_s = us;
       kdir->tables[table].add = (uint)ntable;
       ntable->pages[page].pre = pre;
       ntable->pages[page].r_w = rw;
       ntable->pages[page].u_s = us;
       ntable->pages[page].add = add;
    }
}
 void vmem::install()
{
    video v;
    phmman phm;extern uint knl_end;
    kdir = (dir_t *)phm.allocpg();
    kdir = (dir_t *)phm.allocpg();

    for(int i=0;i<= knl_end;i += 4096)
    {
        alloc(i,1,1,0);
    }
    //v.puthex("",(int)kdir);
    load((uint*)kdir);
}

Code: Select all

#ifndef _H_virtual_memory_
#define _H_virtual_memory_
#include "phmem.h"
#include "system.h"

typedef struct page_entery
{
    uint pre:1;
    uint r_w:1;
    uint u_s:1;
    uint acc:1;
    uint dir:1;
    uint rev:7;
    uint add:20;
}page_e;
typedef struct page_table
{
    page_e pages[1024];
}page_t;
typedef struct dir_entry
{
    uint pre:1;
    uint r_w:1;
    uint u_s:1;
    uint acc:1;
    uint dir:1;
    uint rev:7;
    uint add:20;
}dir_e;
typedef struct dir_table
{
    dir_e tables[1024];
}dir_t;

class vmem
{
public:
      void install();
      void alloc(uint add,int pre,int rw,int us);
};
#endif