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Kernel: Fix 32 bit MMU

This commit is contained in:
Bananymous 2023-04-22 18:22:39 +03:00
parent 48445f12ac
commit fb6add2b4a
1 changed files with 32 additions and 6 deletions
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38
kernel/arch/i386/MMU.cpp
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@ -109,23 +109,43 @@ MMU::MMU()
m_highest_paging_struct = pdpt; m_highest_paging_struct = pdpt;
} }
MMU::~MMU()
{
uint64_t* pdpt = m_highest_paging_struct;
for (uint32_t pdpte = 0; pdpte < 512; pdpte++)
{
if (!(pdpt[pdpte] & Flags::Present))
continue;
uint64_t* pd = (uint64_t*)(pdpt[pdpte] & PAGE_MASK);
for (uint32_t pde = 0; pde < 512; pde++)
{
if (!(pd[pde] & Flags::Present))
continue;
kfree((void*)(pd[pde] & PAGE_MASK));
}
kfree(pd);
}
kfree(pdpt);
}
void MMU::load() void MMU::load()
{ {
asm volatile("movl %0, %%cr3" :: "r"(m_highest_paging_struct)); asm volatile("movl %0, %%cr3" :: "r"(m_highest_paging_struct));
} }
void MMU::map_page(uintptr_t address, uint8_t flags) void MMU::map_page_at(paddr_t paddr, vaddr_t vaddr, uint8_t flags)
{ {
#if MMU_DEBUG_PRINT #if MMU_DEBUG_PRINT
dprintln("AllocatePage(0x{8H})", address); dprintln("AllocatePage(0x{8H})", address);
#endif #endif
ASSERT(flags & Flags::Present); ASSERT(flags & Flags::Present);
address &= PAGE_MASK; ASSERT(!(paddr & ~PAGE_MASK));
ASSERT(!(vaddr & ~PAGE_MASK));
uint32_t pdpte = (address & 0xC0000000) >> 30; uint32_t pdpte = (vaddr & 0xC0000000) >> 30;
uint32_t pde = (address & 0x3FE00000) >> 21; uint32_t pde = (vaddr & 0x3FE00000) >> 21;
uint32_t pte = (address & 0x001FF000) >> 12; uint32_t pte = (vaddr & 0x001FF000) >> 12;
uint64_t* page_directory = (uint64_t*)(m_highest_paging_struct[pdpte] & PAGE_MASK); uint64_t* page_directory = (uint64_t*)(m_highest_paging_struct[pdpte] & PAGE_MASK);
if (!(page_directory[pde] & Flags::Present)) if (!(page_directory[pde] & Flags::Present))
@ -136,7 +156,13 @@ void MMU::map_page(uintptr_t address, uint8_t flags)
page_directory[pde] |= flags; page_directory[pde] |= flags;
uint64_t* page_table = (uint64_t*)(page_directory[pde] & PAGE_MASK); uint64_t* page_table = (uint64_t*)(page_directory[pde] & PAGE_MASK);
page_table[pte] = address | flags; page_table[pte] = paddr | flags;
}
void MMU::map_page(uintptr_t address, uint8_t flags)
{
address &= PAGE_MASK;
map_page_at(address, address, flags);
} }
void MMU::map_range(uintptr_t address, ptrdiff_t size, uint8_t flags) void MMU::map_range(uintptr_t address, ptrdiff_t size, uint8_t flags)