Kernel/core/memory/page_table.cpp
2024-01-19 06:47:42 +02:00

91 lines
2.7 KiB
C++

#include <memory.hpp>
#include <filesystem.hpp>
#include <signal.hpp>
#include <utsname.h>
#include <time.h>
namespace Memory
{
void PageTable::Update()
{
#if defined(a86)
asmv("mov %0, %%cr3" ::"r"(this));
#elif defined(aa64)
asmv("msr ttbr0_el1, %0" ::"r"(this));
#endif
}
PageTable *PageTable::Fork()
{
PageTable *NewTable = (PageTable *)KernelAllocator.RequestPages(TO_PAGES(sizeof(PageTable)));
// memset(NewTable, 0, sizeof(PageTable));
// CreatePageTable(NewTable);
memcpy(NewTable, this, sizeof(PageTable));
debug("Forking page table %#lx to %#lx", this, NewTable);
#if defined(a64)
for (size_t i = 0; i < sizeof(Entries) / sizeof(Entries[0]); i++)
{
PageMapLevel4 *PML4 = &Entries[i];
PageMapLevel4 *NewPML4 = &NewTable->Entries[i];
if (!PML4->Present)
continue;
PageDirectoryPointerTableEntryPtr *ptrPDPT = (PageDirectoryPointerTableEntryPtr *)(PML4->GetAddress() << 12);
PageDirectoryPointerTableEntryPtr *ptrNewPDPT = (PageDirectoryPointerTableEntryPtr *)KernelAllocator.RequestPage();
NewPML4->SetAddress((uintptr_t)ptrNewPDPT >> 12);
for (size_t j = 0; j < sizeof(ptrPDPT->Entries) / sizeof(ptrPDPT->Entries[0]); j++)
{
PageDirectoryPointerTableEntry *PDPT = &ptrPDPT->Entries[j];
PageDirectoryPointerTableEntry *NewPDPT = &ptrNewPDPT->Entries[j];
*NewPDPT = *PDPT;
if (!PDPT->Present)
continue;
if (PDPT->PageSize)
continue;
PageDirectoryEntryPtr *ptrPDE = (PageDirectoryEntryPtr *)(PDPT->GetAddress() << 12);
PageDirectoryEntryPtr *ptrNewPDE = (PageDirectoryEntryPtr *)KernelAllocator.RequestPage();
NewPDPT->SetAddress((uintptr_t)ptrNewPDE >> 12);
for (size_t k = 0; k < sizeof(ptrPDE->Entries) / sizeof(ptrPDE->Entries[0]); k++)
{
PageDirectoryEntry *PDE = &ptrPDE->Entries[k];
PageDirectoryEntry *NewPDE = &ptrNewPDE->Entries[k];
*NewPDE = *PDE;
if (!PDE->Present)
continue;
if (PDE->PageSize)
continue;
PageTableEntryPtr *ptrPTE = (PageTableEntryPtr *)(PDE->GetAddress() << 12);
PageTableEntryPtr *ptrNewPTE = (PageTableEntryPtr *)KernelAllocator.RequestPage();
NewPDE->SetAddress((uintptr_t)ptrNewPTE >> 12);
for (size_t l = 0; l < sizeof(ptrPTE->Entries) / sizeof(ptrPTE->Entries[0]); l++)
{
PageTableEntry *PTE = &ptrPTE->Entries[l];
PageTableEntry *NewPTE = &ptrNewPTE->Entries[l];
*NewPTE = *PTE;
}
}
}
}
#else
#error "PageTable::Fork() not implemented for other architectures"
#endif
debug("Forked page table %#lx to %#lx", this, NewTable);
return NewTable;
}
/* We can't have Memory::Virtual in the header */
void *PageTable::__getPhysical(void *Address)
{
Virtual vmm(this);
void *PhysAddr = vmm.GetPhysical((void *)Address);
return PhysAddr;
}
}