public override void SetExecutionProtectionForAllInitialPages(LinkedMemoryRegion *currentTextSection)
{
// Must be enabled before setting the page bits, otherwise you get a PageFault exception because of using an reserved bit.
EnableExecutionProtection();
PageTableEntry *pte = (PageTableEntry *)PageTableEntries;
for (uint index = 0; index < InitialPageTableEntries; index++)
{
var virtAddr = index * 4096;
var reg = currentTextSection;
var regionMatches = false;
while (reg != null)
{
if (reg->Region.Contains(virtAddr))
{
regionMatches = true;
break;
}
reg = reg->Next;
}
if (regionMatches)
{
continue;
}
var e = &pte[index];
e->DisableExecution = true;
}
}
public const uint PageTablesMaxSize = PageTablesMaxCount * PageTableEntry.EntrySize; //Size of 1024 PageTables in 1024 PageDirectories
/// <summary>
/// Sets up the PageTable
/// </summary>
public static void Setup()
{
pageDirectoryEntries = (PageDirectoryEntry *)pageDirectoryAddress;
pageTableEntries = (PageTableEntry *)pageTableAddress;
ClearPageDirectory();
ClearPageTable();
// Map the first 128MB of memory (32768 4K pages) (why 128MB?)
for (uint index = 0; index < 1024 * 32; index++)
{
AllocatePage();
}
MapVirtualAddressToPhysical(0xFFC00000, 0x0);
MapVirtualAddressToPhysical(0x0, 0x0, false);
//Panic.DumpMemory(pageDirectoryAddress);
// Set CR3 register on processor - sets page directory
Native.SetCR3(pageDirectoryAddress);
// Set CR0 register on processor - turns on virtual memory
Native.SetCR0(Native.GetCR0() | BitMask.Bit31);
unsafe
{
//Panic.Error(Mosa.ClassLib.FlechterChecksum.Fletcher16((byte*)pageDirectoryAddress, PageDirectorySize));
}
}
public override void SetKernelWriteProtectionForAllInitialPages()
{
PageTableEntry *pte = PageTableEntries;
for (int index = 0; index < InitialPageTableEntries; index++)
{
var e = &pte[index];
e->Writable = false;
}
}
private static PageDirectoryEntry *RegisterPage(PageTableEntry *page)
{
if (currentDictionaryEntryCount == 0 || currentTableEntryCount == 1024)
{
currentDictionaryEntryCount++;
var dicEntry = GetPageDirectoryEntry(currentDictionaryEntryCount - 1);
dicEntry->PageTableEntry = page;
dicEntry->Present = true;
dicEntry->Writable = true;
dicEntry->User = true;
currentTableEntryCount = 0;
}
return(GetPageDirectoryEntry(currentDictionaryEntryCount - 1));
}
/// <summary>
/// Sets up the PageTable
/// </summary>
public static void Setup(Addr addrPageDirectory, Addr addrPageTable)
{
KernelMessage.WriteLine("Setup PageTable");
AddrPageDirectory = addrPageDirectory;
AddrPageTable = addrPageTable;
// Setup Page Directory
PageDirectoryEntry *pde = (PageDirectoryEntry *)AddrPageDirectory;
for (int index = 0; index < 1024; index++)
{
pde[index] = new PageDirectoryEntry();
pde[index].Present = true;
pde[index].Writable = true;
pde[index].User = true;
pde[index].PageTableEntry = (PageTableEntry *)(uint)(AddrPageTable + (index * 4096));
}
// Map the first 128MB of memory (32786 4K pages) (why 128MB?)
for (int index = 0; index < 1024 * 32; index++)
{
PageTableEntry *pte = (PageTableEntry *)AddrPageTable;
pte[index] = new PageTableEntry();
pte[index].Present = true;
pte[index].Writable = true;
pte[index].User = true;
pte[index].PhysicalAddress = (uint)(index * 4096);
}
// Unmap the first page for null pointer exceptions
MapVirtualAddressToPhysical(0x0, 0x0, false);
// Set CR3 register on processor - sets page directory
KernelMessage.WriteLine("Set CR3 to {0:X8}", PageTable.AddrPageDirectory);
Native.SetCR3(AddrPageDirectory);
KernelMessage.Write("Enable Paging... ");
// Set CR0.WP
Native.SetCR0(Native.GetCR0() | 0x10000);
// Set CR0 register on processor - turns on virtual memory
Native.SetCR0(Native.GetCR0() | 0x80000000);
KernelMessage.WriteLine("Done");
}
private void SetupBasicStructure(Addr entriesAddr)
{
KernelMessage.WriteLine("Setup PageTable");
MemoryOperation.Clear4(entriesAddr, InitalMemoryAllocationSize);
PageDirectoryEntries = (PageDirectoryEntry *)entriesAddr;
PageTableEntries = (PageTableEntry *)(entriesAddr + InitalPageDirectorySize);
// Setup Page Directory
PageDirectoryEntry *pde = PageDirectoryEntries;
PageTableEntry * pte = PageTableEntries;
KernelMessage.WriteLine("Total Page Entries: {0}", InitialPageTableEntries);
KernelMessage.WriteLine("Total Page Dictionary Entries: {0}", InitialDirectoryEntries);
//for (int pidx = 0; pidx < InitialPageTableEntries; pidx++)
//{
// pte[pidx] = new PageTableEntry
// {
// Present = true,
// Writable = true,
// User = true,
// PhysicalAddress = (uint)(pidx * 4096),
// };
//}
for (int didx = 0; didx < InitialDirectoryEntries; didx++)
{
pde[didx] = new PageDirectoryEntry
{
Present = true,
Writable = true,
User = true,
PageTableEntry = &pte[didx * PagesPerDictionaryEntry],
};
}
// Unmap the first page for null pointer exceptions
//MapVirtualAddressToPhysical(0x0, 0x0, false);
PrintAddress();
}
/// <summary>
/// Sets up the PageTable
/// </summary>
public static void Setup()
{
pageDirectoryEntries = (PageDirectoryEntry*)pageDirectoryAddress;
pageTableEntries = (PageTableEntry*)pageTableAddress;
ClearPageDirectory();
ClearPageTable();
// Map the first 128MB of memory (32768 4K pages) (why 128MB?)
for (uint index = 0; index < 1024 * 32; index++)
AllocatePage();
MapVirtualAddressToPhysical(0xFFC00000, 0x0);
MapVirtualAddressToPhysical(0x0, 0x0, false);
//Panic.DumpMemory(pageDirectoryAddress);
// Set CR3 register on processor - sets page directory
Native.SetCR3(pageDirectoryAddress);
// Set CR0 register on processor - turns on virtual memory
Native.SetCR0(Native.GetCR0() | BitMask.Bit31);
unsafe
{
//Panic.Error(Mosa.ClassLib.FlechterChecksum.Fletcher16((byte*)pageDirectoryAddress, PageDirectorySize));
}
}
public override void KernelSetup(Addr entriesAddr)
{
PageDirectoryEntries = (PageDirectoryEntry *)entriesAddr;
PageTableEntries = (PageTableEntry *)(entriesAddr + InitalPageDirectorySize);
//PrintAddress();
}
private void SetupBasicStructure(Addr entriesAddr)
{
KernelMessage.WriteLine("Setup PageTable");
SetAddress(entriesAddr);
MemoryOperation.Clear4(AddrPageDirectoryPT, InitalMemoryAllocationSize);
// uint mask = 0x00004000;
// uint v1 = 0x00000007;
// uint r1 = v1.SetBits(12, 52, mask, 12);
// ulong v2 = v1;
// ulong r2 = v2.SetBits(12, 52, mask, 12);
// uint r2Int = (uint)r2;
// KernelMessage.WriteLine("r1: {0:X8}", r1);
// KernelMessage.WriteLine("r2: {0:X8}", r2Int);
// Setup Page Directory
PageDirectoryPointerTableEntry *pdpt = (PageDirectoryPointerTableEntry *)AddrPageDirectoryPT;
PageDirectoryEntry * pde = (PageDirectoryEntry *)AddrPageDirectory;
PageTableEntry *pte = PageTableEntries;
KernelMessage.WriteLine("Total PDPT: {0}", InitialDirectoryPTEntries);
KernelMessage.WriteLine("Total Page Dictionary Entries: {0}", InitialDirectoryEntries);
KernelMessage.WriteLine("Total Page Table Entries: {0}", InitialPageTableEntries);
//for (int pidx = 0; pidx < InitialPageTableEntries; pidx++)
//{
// pte[pidx] = new PageTableEntry
// {
// Present = true,
// Writable = true,
// User = true,
// PhysicalAddress = (uint)(pidx * 4096),
// };
//}
for (int didx = 0; didx < InitialDirectoryEntries; didx++)
{
pde[didx] = new PageDirectoryEntry
{
Present = true,
Writable = true,
User = true,
PageTableEntry = &pte[didx * PagesPerDictionaryEntry],
};
}
for (int ptidx = 0; ptidx < InitialDirectoryPTEntries; ptidx++)
{
pdpt[ptidx] = new PageDirectoryPointerTableEntry
{
Present = true,
PageDirectoryEntry = &pde[ptidx * PagesPerDictionaryEntry],
};
}
// Unmap the first page for null pointer exceptions
//MapVirtualAddressToPhysical(0x0, 0x0, false);
PrintAddress();
}
private void SetAddress(Addr entriesAddr)
{
AddrPageDirectoryPT = entriesAddr;
AddrPageDirectory = entriesAddr + InitalPageDirectoryPTSize;
PageTableEntries = (PageTableEntry *)(entriesAddr + InitalPageDirectoryPTSize + InitalPageDirectorySize);
}
