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typedef struct page
{
   uint present    : 1;   // Page present in memory
   uint rw         : 1;   // Read-only if clear, readwrite if set
   uint user       : 1;   // Supervisor level only if clear
   uint accessed   : 1;   // Has the page been accessed since last refresh?
   uint dirty      : 1;   // Has the page been written to since last refresh?
   uint unused     : 7;   // Amalgamation of unused and reserved bits
   uint frame      : 20;  // Frame address (shifted right 12 bits)
} __packed page_t;

typedef struct{
	page_t p[1024];
}__packed page_table_t;

typedef struct{
	page_table_t *tabs[1024];
}__packed page_dir_t;

page_dir_t *page_dir;
page_table_t *kpage_tables;

void init_identity_paging(){
	uint32_t frame;int i;
	page_dir=k_AllocPage(1,OWNER_PAGEMAN);
	memset(page_dir,0,sizeof(page_dir_t));
	for(i=0;i<1024;i++){
		page_dir->tabs[i]=0 ; 
	}
	
	for(frame=0;frame<=(MEM_SIZE/0x1000);frame++){
		mmap_to(frame,frame,1,1,1);

	}

	stopints();
	write_cr3(page_dir);
	write_cr0(read_cr0()|0x80000000); //set paging bit.
	kput_hex(*(uint32_t*) &page_dir->tabs[0]);
	kputs("\n");
	startints();
}
		
		

void mmap_to(uint32_t src_page,uint32_t trg_page,int present,int rw,int user){
	int i=1;
	if(((uint32_t)page_dir->tabs[src_page/1024] & 0xFFFFF000)==0){

		page_dir->tabs[src_page/1024]=(void*)
				((uint32_t)k_AllocPage(1,OWNER_PAGEMAN) | 7);
		for(i=0;i<1024;i++){
			
			page_dir->tabs[src_page/1024]->p[i].present=0;
			page_dir->tabs[src_page/1024]->p[i].rw=0;
			page_dir->tabs[src_page/1024]->p[i].user=0;
			page_dir->tabs[src_page/1024]->p[i].frame=0;
		}
	}
	
	page_dir->tabs[src_page/1024]->p[src_page%1024].present=present;
	page_dir->tabs[src_page/1024]->p[src_page%1024].rw=rw;
	page_dir->tabs[src_page/1024]->p[src_page%1024].user=user;
	page_dir->tabs[src_page/1024]->p[src_page%1024].frame=trg_page;
	
}