91 lines
2.3 KiB
C
91 lines
2.3 KiB
C
#include "assert.H"
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#include "exceptions.H"
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#include "console.H"
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#include "paging_low.H"
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#include "page_table.H"
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PageTable * PageTable::current_page_table = NULL;
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unsigned int PageTable::paging_enabled = 0;
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ContFramePool * PageTable::kernel_mem_pool = NULL;
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ContFramePool * PageTable::process_mem_pool = NULL;
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unsigned long PageTable::shared_size = 0;
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void PageTable::init_paging(ContFramePool * _kernel_mem_pool,
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ContFramePool * _process_mem_pool,
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const unsigned long _shared_size)
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{
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kernel_mem_pool = _kernel_mem_pool;
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process_mem_pool = process_mem_pool;
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shared_size = _shared_size;
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Console::puts("\nInitialized Paging System\n");
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}
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PageTable::PageTable()
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{
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//kernel_mem_pool->get_frames(1); // Need to take one frame for page directory.
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//page_directory = (unsigned long *) 0x32000; // Should be the starting address after 1st 2MB
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page_directory = (unsigned long *) kernel_mem_pool->get_frames(1); // Should I get the address like this???
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//unsigned long * page_table = (unsigned long *) 0x33000; // Should be 4kb after the page directory.
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unsigned long * page_table = page_directory + 0x1000; // Might be able to just do this.
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unsigned long tempaddr; // Temporary address iterator.
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// We need to map the first 4MB.
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for(unsigned int i = 0; i < 1024; i++)
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{
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page_table[i] = tempaddr | 3; // set bits 0 and 1 to present and read/write respectively
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tempaddr += 4096; // 4096 = 4kb
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}
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// Fill first entry of page directory.
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page_directory[0] = *page_table;
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page_directory[0] = page_directory[0] | 3;
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for(unsigned int j = 1; j < 1024; j++)
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{
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page_directory[j] = 0 | 2;
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}
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current_page_table = this;
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Console::puts("\nConstructed Page Table object\n");
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}
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void PageTable::load()
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{
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write_cr3(*page_directory);
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current_page_table = this;
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Console::puts("\nLoaded page table\n");
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}
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void PageTable::enable_paging()
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{
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write_cr3(*current_page_table->page_directory);
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write_cr0(read_cr0() | 0x80000000);
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paging_enabled = read_cr0();
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Console::puts("\nEnabled paging\n");
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}
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void PageTable::handle_fault(REGS * _r)
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{
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/*
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unsigned long tempframe = process_mem_pool->get_frames(1);
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Console::puts("\nerror code: ");
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Console::puti(_r->err_code);
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unsigned char mask = 0x00;
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read_cr2();
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*/
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assert(false);
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Console::puts("\nhandled page fault\n");
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}
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