include/09.paging/paging04.c


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void set_pt(size_t num,uint32_t address)
{
    // holds the physical address where we want to start mapping these pages to.
    // in this case, we want to map these pages to the very beginning of memory.
    //we will fill all 1024 entries in the table, mapping 4 megabytes
    for(size_t i=0;i<1024;i++)
    {
	// As the address is page aligned, it will always leave 12 bits zeroed.
	// Those bits are used by the attributes ;)
	page_table[num][i] = (address + i * 0x1000) | 3; // attributes: supervisor level, read/write, present.
    }

    page_directory[num] = ((uint32_t)page_table[num]) | 3;
    // attributes: supervisor level, read/write, present
}