VOID
MiUpdateSystemPdes (
IN PEPROCESS Process
)
/*++
Routine Description:
This routine updates the system PDEs, typically due to a large page
system PTE mapping being created or destroyed. This is rare.
Note this is only needed for 32-bit platforms (64-bit platforms share
a common top level system page).
Arguments:
Process - Supplies a pointer to the process to update.
Return Value:
None.
Environment:
Kernel mode, expansion lock held.
The caller acquired the expansion lock prior to clearing the update
bit from this process. We must update the PDEs prior to releasing
it so that any new updates can also be rippled.
--*/
{
ULONG i;
ULONG PdeOffset;
ULONG PdeEndOffset;
MMPTE TempPte;
PFN_NUMBER PageDirectoryIndex;
PFN_NUMBER TargetPageDirectoryIndex;
PEPROCESS CurrentProcess;
PMMPTE PointerPte;
PMMPTE PointerPde;
PMMPTE TargetPdePage;
PMMPTE TargetAddressSpacePde;
ASSERT (KeGetCurrentIrql () == DISPATCH_LEVEL);
CurrentProcess = PsGetCurrentProcess ();
//
// Map the page directory page in hyperspace.
// Note for PAE, this is the high 1GB virtual only.
//
ASSERT (Process->Pcb.DirectoryTableBase[0] != 0);
TargetPageDirectoryIndex = Process->Pcb.DirectoryTableBase[0] >> PAGE_SHIFT;
ASSERT (PsInitialSystemProcess != NULL);
ASSERT (PsInitialSystemProcess->Pcb.DirectoryTableBase[0] != 0);
PageDirectoryIndex = PsInitialSystemProcess->Pcb.DirectoryTableBase[0] >> PAGE_SHIFT;
TempPte = ValidKernelPte;
TempPte.u.Hard.PageFrameNumber = TargetPageDirectoryIndex;
ASSERT (MiLargePageHyperPte->u.Long == 0);
MI_WRITE_VALID_PTE (MiLargePageHyperPte, TempPte);
TargetPdePage = MiGetVirtualAddressMappedByPte (MiLargePageHyperPte);
//
// Map the system process page directory as we know that's always kept
// up to date.
//
PointerPte = MiMapPageInHyperSpaceAtDpc (CurrentProcess,
PageDirectoryIndex);
//
// Copy all system PTE ranges.
//
for (i = 0; i < MiPteRangeIndex; i += 1) {
PdeOffset = MiGetPdeOffset (MiPteRanges[i].StartingVa);
PdeEndOffset = MiGetPdeOffset (MiPteRanges[i].EndingVa);
PointerPde = &PointerPte[PdeOffset];
TargetAddressSpacePde = &TargetPdePage[PdeOffset];
RtlCopyMemory (TargetAddressSpacePde,
PointerPde,
(PdeEndOffset - PdeOffset + 1) * sizeof (MMPTE));
}
MiUnmapPageInHyperSpaceFromDpc (CurrentProcess, PointerPte);
//
// Just invalidate the mapping on the current processor as we cannot
// have context switched.
//
MI_WRITE_ZERO_PTE (MiLargePageHyperPte);
MI_FLUSH_CURRENT_TB_SINGLE (TargetPdePage);
return;
}
VOID
MiUpdateSystemPdes (
IN PEPROCESS Process
)
/*++
Routine Description:
This routine updates the system PDEs, typically due to a large page
system PTE mapping being created or destroyed. This is rare.
Note this is only needed for 32-bit platforms (64-bit platforms share
a common top level system page).
Arguments:
Process - Supplies a pointer to the process to update.
Return Value:
None.
Environment:
Kernel mode, expansion lock held.
The caller acquired the expansion lock prior to clearing the update
bit from this process. We must update the PDEs prior to releasing
it so that any new updates can also be rippled.
--*/
{
ULONG PdeOffset;
ULONG PdeEndOffset;
LOGICAL LowPtes;
PVOID VirtualAddress;
MMPTE TempPte;
PFN_NUMBER PageDirectoryIndex;
PFN_NUMBER TargetPageDirectoryIndex;
PEPROCESS CurrentProcess;
PMMPTE PointerPte;
PMMPTE PointerPde;
PMMPTE TargetPdePage;
PMMPTE TargetAddressSpacePde;
PMMPTE PaeTop;
ULONG i;
ASSERT (KeGetCurrentIrql () == DISPATCH_LEVEL);
CurrentProcess = PsGetCurrentProcess ();
//
// Map the page directory page in hyperspace.
// Note for PAE, this is the high 1GB virtual only.
//
PaeTop = Process->PaeTop;
ASSERT (PaeTop != NULL);
PaeTop += 3;
ASSERT (PaeTop->u.Hard.Valid == 1);
TargetPageDirectoryIndex = (PFN_NUMBER)(PaeTop->u.Hard.PageFrameNumber);
PaeTop = &MiSystemPaeVa.PteEntry[PD_PER_SYSTEM - 1];
ASSERT (PaeTop->u.Hard.Valid == 1);
PageDirectoryIndex = (PFN_NUMBER)(PaeTop->u.Hard.PageFrameNumber);
TempPte = ValidKernelPte;
TempPte.u.Hard.PageFrameNumber = TargetPageDirectoryIndex;
ASSERT (MiLargePageHyperPte->u.Long == 0);
MI_WRITE_VALID_PTE (MiLargePageHyperPte, TempPte);
TargetPdePage = MiGetVirtualAddressMappedByPte (MiLargePageHyperPte);
LowPtes = FALSE;
//
// Map the system process page directory as we know that's always kept
// up to date.
//
PointerPte = MiMapPageInHyperSpaceAtDpc (CurrentProcess,
PageDirectoryIndex);
//
// Copy all system PTE ranges that reside in the top 1GB.
//
for (i = 0; i < MiPteRangeIndex; i += 1) {
VirtualAddress = MiPteRanges[i].StartingVa;
if (VirtualAddress < (PVOID) 0xC0000000) {
LowPtes = TRUE;
continue;
}
PdeOffset = MiGetPdeOffset (VirtualAddress);
PdeEndOffset = MiGetPdeOffset (MiPteRanges[i].EndingVa);
PointerPde = &PointerPte[PdeOffset];
TargetAddressSpacePde = &TargetPdePage[PdeOffset];
RtlCopyMemory (TargetAddressSpacePde,
PointerPde,
(PdeEndOffset - PdeOffset + 1) * sizeof (MMPTE));
}
MiUnmapPageInHyperSpaceFromDpc (CurrentProcess, PointerPte);
//
// Just invalidate the mapping on the current processor as we cannot
// have context switched.
//
MI_WRITE_ZERO_PTE (MiLargePageHyperPte);
MI_FLUSH_CURRENT_TB_SINGLE (TargetPdePage);
ASSERT (MmSystemRangeStart >= (PVOID) 0x80000000);
//
// Copy low additional system PTE ranges (if they exist).
//
if (LowPtes == TRUE) {
ASSERT (MmSystemRangeStart < (PVOID) 0xC0000000);
//
// Map the target process' page directory.
//
PaeTop = Process->PaeTop;
ASSERT (PaeTop != NULL);
PaeTop += 2;
ASSERT (PaeTop->u.Hard.Valid == 1);
TargetPageDirectoryIndex = (PFN_NUMBER)(PaeTop->u.Hard.PageFrameNumber);
TempPte.u.Hard.PageFrameNumber = TargetPageDirectoryIndex;
ASSERT (MiLargePageHyperPte->u.Long == 0);
MI_WRITE_VALID_PTE (MiLargePageHyperPte, TempPte);
//
// Map the system's page directory.
//
PaeTop = &MiSystemPaeVa.PteEntry[PD_PER_SYSTEM - 2];
ASSERT (PaeTop->u.Hard.Valid == 1);
PageDirectoryIndex = (PFN_NUMBER)(PaeTop->u.Hard.PageFrameNumber);
PdeOffset = MiGetPdeOffset (MmSystemRangeStart);
TargetAddressSpacePde = &TargetPdePage[PdeOffset];
PointerPte = MiMapPageInHyperSpaceAtDpc (CurrentProcess,
PageDirectoryIndex);
//
// Copy all system ranges that reside in the 3rd GB.
//
for (i = 0; i < MiPteRangeIndex; i += 1) {
VirtualAddress = MiPteRanges[i].StartingVa;
if (VirtualAddress < (PVOID) 0xC0000000) {
PdeOffset = MiGetPdeOffset (VirtualAddress);
PdeEndOffset = MiGetPdeOffset (MiPteRanges[i].EndingVa);
PointerPde = &PointerPte[PdeOffset];
TargetAddressSpacePde = &TargetPdePage[PdeOffset];
RtlCopyMemory (TargetAddressSpacePde,
PointerPde,
(PdeEndOffset - PdeOffset + 1) * sizeof (MMPTE));
}
}
MiUnmapPageInHyperSpaceFromDpc (CurrentProcess, PointerPte);
//
// Just invalidate the mapping on the current processor as we cannot
// have context switched.
//
MI_WRITE_ZERO_PTE (MiLargePageHyperPte);
MI_FLUSH_CURRENT_TB_SINGLE (TargetPdePage);
}
return;
}
