Sinipelto
/
banan-os
forked from Bananymous/banan-os
1
0
Fork 0
Code Pull Requests Activity

Kernel: Add debug print to MMU and fix comment

This commit is contained in:
Bananymous 2023-01-12 13:46:02 +02:00
parent 301ad89783
commit 5493d1bae1
1 changed files with 11 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
kernel/arch/i386/MMU.cpp
View File

@ -5,6 +5,8 @@
#include <string.h> #include <string.h>
#define MMU_DEBUG_PRINT 1
#define PRESENT (1 << 0) #define PRESENT (1 << 0)
#define READ_WRITE (1 << 1) #define READ_WRITE (1 << 1)
@ -41,7 +43,7 @@ MMU::MMU()
ASSERT(m_page_descriptor_pointer_table); ASSERT(m_page_descriptor_pointer_table);
ASSERT(((uintptr_t)m_page_descriptor_pointer_table % 32) == 0); ASSERT(((uintptr_t)m_page_descriptor_pointer_table % 32) == 0);
// create and zero out all page directories // allocate all page directories
for (int i = 0; i < 4; i++) for (int i = 0; i < 4; i++)
{ {
uint64_t* page_directory = allocate_page_aligned_page(); uint64_t* page_directory = allocate_page_aligned_page();
@ -70,12 +72,14 @@ MMU::MMU()
void MMU::AllocatePage(uintptr_t address) void MMU::AllocatePage(uintptr_t address)
{ {
#if MMU_DEBUG_PRINT
dprintln("AllocatePage(0x{8H})", address & PAGE_MASK);
#endif
uint32_t pdpte = (address & 0xC0000000) >> 30; uint32_t pdpte = (address & 0xC0000000) >> 30;
uint32_t pde = (address & 0x3FE00000) >> 21; uint32_t pde = (address & 0x3FE00000) >> 21;
uint32_t pte = (address & 0x001FF000) >> 12; uint32_t pte = (address & 0x001FF000) >> 12;
ASSERT(pdpte < 4);
uint64_t* page_directory = (uint64_t*)(m_page_descriptor_pointer_table[pdpte] & PAGE_MASK); uint64_t* page_directory = (uint64_t*)(m_page_descriptor_pointer_table[pdpte] & PAGE_MASK);
if (!(page_directory[pde] & PRESENT)) if (!(page_directory[pde] & PRESENT))
{ {
@ -99,6 +103,10 @@ void MMU::AllocateRange(uintptr_t address, ptrdiff_t size)
void MMU::UnAllocatePage(uintptr_t address) void MMU::UnAllocatePage(uintptr_t address)
{ {
#if MMU_DEBUG_PRINT
dprintln("UnAllocatePage(0x{8H})", address & PAGE_MASK);
#endif
uint32_t pdpte = (address & 0xC0000000) >> 30; uint32_t pdpte = (address & 0xC0000000) >> 30;
uint32_t pde = (address & 0x3FE00000) >> 21; uint32_t pde = (address & 0x3FE00000) >> 21;
uint32_t pte = (address & 0x001FF000) >> 12; uint32_t pte = (address & 0x001FF000) >> 12;