VOID
MiCheckPfn (
)
/*++
Routine Description:
This routine checks each physical page in the PFN database to ensure
it is in the proper state.
Arguments:
None.
Return Value:
None.
Environment:
Kernel mode, APCs disabled.
--*/
{
PMMPFN Pfn1;
PFN_NUMBER Link, Previous;
ULONG i;
PMMPTE PointerPte;
KIRQL PreviousIrql;
KIRQL OldIrql;
USHORT ValidCheck[4];
USHORT ValidPage[4];
PMMPFN PfnX;
ValidCheck[0] = ValidCheck[1] = ValidCheck[2] = ValidCheck[3] = 0;
ValidPage[0] = ValidPage[1] = ValidPage[2] = ValidPage[3] = 0;
if (CheckPfnBitMap == NULL) {
MiCreateBitMap ( &CheckPfnBitMap, MmNumberOfPhysicalPages, NonPagedPool);
}
RtlClearAllBits (CheckPfnBitMap);
//
// Walk free list.
//
KeRaiseIrql (APC_LEVEL, &PreviousIrql);
LOCK_PFN (OldIrql);
Previous = MM_EMPTY_LIST;
Link = MmFreePageListHead.Flink;
for (i=0; i < MmFreePageListHead.Total; i++) {
if (Link == MM_EMPTY_LIST) {
DbgPrint("free list total count wrong\n");
UNLOCK_PFN (OldIrql);
KeLowerIrql (PreviousIrql);
return;
}
RtlSetBits (CheckPfnBitMap, (ULONG)Link, 1L);
Pfn1 = MI_PFN_ELEMENT(Link);
if (Pfn1->u3.e2.ReferenceCount != 0) {
DbgPrint("non zero reference count on free list\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u3.e1.PageLocation != FreePageList) {
DbgPrint("page location not freelist\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u2.Blink != Previous) {
DbgPrint("bad blink on free list\n");
MiFormatPfn(Pfn1);
}
Previous = Link;
Link = Pfn1->u1.Flink;
}
if (Link != MM_EMPTY_LIST) {
DbgPrint("free list total count wrong\n");
Pfn1 = MI_PFN_ELEMENT(Link);
MiFormatPfn(Pfn1);
}
//
// Walk zeroed list.
//
Previous = MM_EMPTY_LIST;
Link = MmZeroedPageListHead.Flink;
for (i=0; i < MmZeroedPageListHead.Total; i++) {
if (Link == MM_EMPTY_LIST) {
DbgPrint("zero list total count wrong\n");
UNLOCK_PFN (OldIrql);
KeLowerIrql (PreviousIrql);
return;
}
RtlSetBits (CheckPfnBitMap, (ULONG)Link, 1L);
Pfn1 = MI_PFN_ELEMENT(Link);
if (Pfn1->u3.e2.ReferenceCount != 0) {
DbgPrint("non zero reference count on zero list\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u3.e1.PageLocation != ZeroedPageList) {
DbgPrint("page location not zerolist\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u2.Blink != Previous) {
DbgPrint("bad blink on zero list\n");
MiFormatPfn(Pfn1);
}
Previous = Link;
Link = Pfn1->u1.Flink;
}
if (Link != MM_EMPTY_LIST) {
DbgPrint("zero list total count wrong\n");
Pfn1 = MI_PFN_ELEMENT(Link);
MiFormatPfn(Pfn1);
}
//
// Walk Bad list.
//
Previous = MM_EMPTY_LIST;
Link = MmBadPageListHead.Flink;
for (i=0; i < MmBadPageListHead.Total; i++) {
if (Link == MM_EMPTY_LIST) {
DbgPrint("Bad list total count wrong\n");
UNLOCK_PFN (OldIrql);
KeLowerIrql (PreviousIrql);
return;
}
RtlSetBits (CheckPfnBitMap, (ULONG)Link, 1L);
Pfn1 = MI_PFN_ELEMENT(Link);
if (Pfn1->u3.e2.ReferenceCount != 0) {
DbgPrint("non zero reference count on Bad list\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u3.e1.PageLocation != BadPageList) {
DbgPrint("page location not Badlist\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u2.Blink != Previous) {
DbgPrint("bad blink on Bad list\n");
MiFormatPfn(Pfn1);
}
Previous = Link;
Link = Pfn1->u1.Flink;
}
if (Link != MM_EMPTY_LIST) {
DbgPrint("Bad list total count wrong\n");
Pfn1 = MI_PFN_ELEMENT(Link);
MiFormatPfn(Pfn1);
}
//
// Walk Standby list.
//
Previous = MM_EMPTY_LIST;
Link = MmStandbyPageListHead.Flink;
for (i=0; i < MmStandbyPageListHead.Total; i++) {
if (Link == MM_EMPTY_LIST) {
DbgPrint("Standby list total count wrong\n");
UNLOCK_PFN (OldIrql);
KeLowerIrql (PreviousIrql);
return;
}
RtlSetBits (CheckPfnBitMap, (ULONG)Link, 1L);
Pfn1 = MI_PFN_ELEMENT(Link);
if (Pfn1->u3.e2.ReferenceCount != 0) {
DbgPrint("non zero reference count on Standby list\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u3.e1.PageLocation != StandbyPageList) {
DbgPrint("page location not Standbylist\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u2.Blink != Previous) {
DbgPrint("bad blink on Standby list\n");
MiFormatPfn(Pfn1);
}
//
// Check to see if referenced PTE is okay.
//
if (MI_IS_PFN_DELETED (Pfn1)) {
DbgPrint("Invalid pteaddress in standby list\n");
MiFormatPfn(Pfn1);
} else {
OldIrql = 99;
if ((Pfn1->u3.e1.PrototypePte == 1) &&
(MmIsAddressValid (Pfn1->PteAddress))) {
PointerPte = Pfn1->PteAddress;
} else {
PointerPte = MiMapPageInHyperSpace(Pfn1->PteFrame,
&OldIrql);
PointerPte = (PMMPTE)((ULONG_PTR)PointerPte +
MiGetByteOffset(Pfn1->PteAddress));
}
if (MI_GET_PAGE_FRAME_FROM_TRANSITION_PTE (PointerPte) != Link) {
DbgPrint("Invalid PFN - PTE address is wrong in standby list\n");
MiFormatPfn(Pfn1);
MiFormatPte(PointerPte);
}
if (PointerPte->u.Soft.Transition == 0) {
DbgPrint("Pte not in transition for page on standby list\n");
MiFormatPfn(Pfn1);
MiFormatPte(PointerPte);
}
if (OldIrql != 99) {
MiUnmapPageInHyperSpace (OldIrql);
OldIrql = 99;
}
}
Previous = Link;
Link = Pfn1->u1.Flink;
}
if (Link != MM_EMPTY_LIST) {
DbgPrint("Standby list total count wrong\n");
Pfn1 = MI_PFN_ELEMENT(Link);
MiFormatPfn(Pfn1);
}
//
// Walk Modified list.
//
Previous = MM_EMPTY_LIST;
Link = MmModifiedPageListHead.Flink;
for (i=0; i < MmModifiedPageListHead.Total; i++) {
if (Link == MM_EMPTY_LIST) {
DbgPrint("Modified list total count wrong\n");
UNLOCK_PFN (OldIrql);
KeLowerIrql (PreviousIrql);
return;
}
RtlSetBits (CheckPfnBitMap, (ULONG)Link, 1L);
Pfn1 = MI_PFN_ELEMENT(Link);
if (Pfn1->u3.e2.ReferenceCount != 0) {
DbgPrint("non zero reference count on Modified list\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u3.e1.PageLocation != ModifiedPageList) {
DbgPrint("page location not Modifiedlist\n");
MiFormatPfn(Pfn1);
}
if (Pfn1->u2.Blink != Previous) {
DbgPrint("bad blink on Modified list\n");
MiFormatPfn(Pfn1);
}
//
// Check to see if referenced PTE is okay.
//
if (MI_IS_PFN_DELETED (Pfn1)) {
DbgPrint("Invalid pteaddress in modified list\n");
MiFormatPfn(Pfn1);
} else {
if ((Pfn1->u3.e1.PrototypePte == 1) &&
(MmIsAddressValid (Pfn1->PteAddress))) {
PointerPte = Pfn1->PteAddress;
} else {
PointerPte = MiMapPageInHyperSpace(Pfn1->PteFrame, &OldIrql);
PointerPte = (PMMPTE)((ULONG_PTR)PointerPte +
MiGetByteOffset(Pfn1->PteAddress));
}
if (MI_GET_PAGE_FRAME_FROM_TRANSITION_PTE (PointerPte) != Link) {
DbgPrint("Invalid PFN - PTE address is wrong in modified list\n");
MiFormatPfn(Pfn1);
MiFormatPte(PointerPte);
}
if (PointerPte->u.Soft.Transition == 0) {
DbgPrint("Pte not in transition for page on modified list\n");
MiFormatPfn(Pfn1);
MiFormatPte(PointerPte);
}
if (OldIrql != 99) {
MiUnmapPageInHyperSpace (OldIrql);
OldIrql = 99;
}
}
Previous = Link;
Link = Pfn1->u1.Flink;
}
if (Link != MM_EMPTY_LIST) {
DbgPrint("Modified list total count wrong\n");
Pfn1 = MI_PFN_ELEMENT(Link);
MiFormatPfn(Pfn1);
}
//
// All non active pages have been scanned. Locate the
// active pages and make sure they are consistent.
//
//
// set bit zero as page zero is reserved for now
//
RtlSetBits (CheckPfnBitMap, 0L, 1L);
Link = RtlFindClearBitsAndSet (CheckPfnBitMap, 1L, 0);
while (Link != 0xFFFFFFFF) {
Pfn1 = MI_PFN_ELEMENT (Link);
//
// Make sure the PTE address is okay
//
if ((Pfn1->PteAddress >= (PMMPTE)HYPER_SPACE)
&& (Pfn1->u3.e1.PrototypePte == 0)) {
DbgPrint("pfn with illegal pte address\n");
MiFormatPfn(Pfn1);
break;
}
if (Pfn1->PteAddress < (PMMPTE)PTE_BASE) {
DbgPrint("pfn with illegal pte address\n");
MiFormatPfn(Pfn1);
break;
}
#if defined(_IA64_)
//
// ignore PTEs mapped to IA64 kernel BAT.
//
if (MI_IS_PHYSICAL_ADDRESS(MiGetVirtualAddressMappedByPte(Pfn1->PteAddress))) {
goto NoCheck;
}
#endif // _IA64_
#ifdef _ALPHA_
//
// ignore ptes mapped to ALPHA's 32-bit superpage.
//
if ((Pfn1->PteAddress > (PMMPTE)(ULONG_PTR)0xc0100000) &&
(Pfn1->PteAddress < (PMMPTE)(ULONG_PTR)0xc0180000)) {
goto NoCheck;
}
#endif //ALPHA
//
// Check to make sure the referenced PTE is for this page.
//
if ((Pfn1->u3.e1.PrototypePte == 1) &&
(MmIsAddressValid (Pfn1->PteAddress))) {
PointerPte = Pfn1->PteAddress;
} else {
PointerPte = MiMapPageInHyperSpace(Pfn1->PteFrame, &OldIrql);
PointerPte = (PMMPTE)((ULONG_PTR)PointerPte +
MiGetByteOffset(Pfn1->PteAddress));
}
if (MI_GET_PAGE_FRAME_FROM_PTE (PointerPte) != Link) {
DbgPrint("Invalid PFN - PTE address is wrong in active list\n");
MiFormatPfn(Pfn1);
MiFormatPte(PointerPte);
}
if (PointerPte->u.Hard.Valid == 0) {
//
// if the page is a page table page it could be out of
// the working set yet a transition page is keeping it
// around in memory (ups the share count).
//
if ((Pfn1->PteAddress < (PMMPTE)PDE_BASE) ||
(Pfn1->PteAddress > (PMMPTE)PDE_TOP)) {
DbgPrint("Pte not valid for page on active list\n");
MiFormatPfn(Pfn1);
MiFormatPte(PointerPte);
}
}
if (Pfn1->u3.e2.ReferenceCount != 1) {
DbgPrint("refcount not 1\n");
MiFormatPfn(Pfn1);
}
//
// Check to make sure the PTE count for the frame is okay.
//
if (Pfn1->u3.e1.PrototypePte == 1) {
PfnX = MI_PFN_ELEMENT(Pfn1->PteFrame);
for (i = 0; i < 4; i++) {
if (ValidPage[i] == 0) {
ValidPage[i] = (USHORT)Pfn1->PteFrame;
}
if (ValidPage[i] == (USHORT)Pfn1->PteFrame) {
ValidCheck[i] += 1;
break;
}
}
}
if (OldIrql != 99) {
MiUnmapPageInHyperSpace (OldIrql);
OldIrql = 99;
}
#if defined(_ALPHA_) || defined(_IA64_)
NoCheck:
#endif
Link = RtlFindClearBitsAndSet (CheckPfnBitMap, 1L, 0);
}
for (i = 0; i < 4; i++) {
if (ValidPage[i] == 0) {
break;
}
PfnX = MI_PFN_ELEMENT(ValidPage[i]);
}
UNLOCK_PFN (OldIrql);
KeLowerIrql (PreviousIrql);
return;
}
VOID
FASTCALL
MiDecrementShareCount (
IN PMMPFN Pfn1,
IN PFN_NUMBER PageFrameIndex
)
/*++
Routine Description:
This routine decrements the share count within the PFN element
for the specified physical page. If the share count becomes
zero the corresponding PTE is converted to the transition state
and the reference count is decremented and the ValidPte count
of the PTEframe is decremented.
Arguments:
Pfn1 - Supplies the PFN database entry to decrement.
PageFrameIndex - Supplies the physical page number of which to decrement
the share count.
Return Value:
None.
Environment:
Must be holding the PFN database lock with APCs disabled.
--*/
{
ULONG FreeBit;
MMPTE TempPte;
PMMPTE PointerPte;
PEPROCESS Process;
ASSERT (PageFrameIndex > 0);
ASSERT (MI_IS_PFN (PageFrameIndex));
ASSERT (Pfn1 == MI_PFN_ELEMENT (PageFrameIndex));
if (Pfn1->u3.e1.PageLocation != ActiveAndValid &&
Pfn1->u3.e1.PageLocation != StandbyPageList) {
KeBugCheckEx (PFN_LIST_CORRUPT,
0x99,
PageFrameIndex,
Pfn1->u3.e1.PageLocation,
0);
}
Pfn1->u2.ShareCount -= 1;
ASSERT (Pfn1->u2.ShareCount < 0xF000000);
if (Pfn1->u2.ShareCount == 0) {
if (PERFINFO_IS_GROUP_ON(PERF_MEMORY)) {
PERFINFO_PFN_INFORMATION PerfInfoPfn;
PerfInfoPfn.PageFrameIndex = PageFrameIndex;
PerfInfoLogBytes(PERFINFO_LOG_TYPE_ZEROSHARECOUNT,
&PerfInfoPfn,
sizeof(PerfInfoPfn));
}
//
// The share count is now zero, decrement the reference count
// for the PFN element and turn the referenced PTE into
// the transition state if it refers to a prototype PTE.
// PTEs which are not prototype PTEs do not need to be placed
// into transition as they are placed in transition when
// they are removed from the working set (working set free routine).
//
//
// If the PTE referenced by this PFN element is actually
// a prototype PTE, it must be mapped into hyperspace and
// then operated on.
//
if (Pfn1->u3.e1.PrototypePte == 1) {
if (MiIsProtoAddressValid (Pfn1->PteAddress)) {
Process = NULL;
PointerPte = Pfn1->PteAddress;
}
else {
//
// The address is not valid in this process, map it into
// hyperspace so it can be operated upon.
//
Process = PsGetCurrentProcess ();
PointerPte = (PMMPTE) MiMapPageInHyperSpaceAtDpc(Process, Pfn1->u4.PteFrame);
PointerPte = (PMMPTE)((PCHAR)PointerPte +
MiGetByteOffset(Pfn1->PteAddress));
}
TempPte = *PointerPte;
MI_MAKE_VALID_PTE_TRANSITION (TempPte,
Pfn1->OriginalPte.u.Soft.Protection);
MI_WRITE_INVALID_PTE (PointerPte, TempPte);
if (Process != NULL) {
MiUnmapPageInHyperSpaceFromDpc (Process, PointerPte);
}
//
// There is no need to flush the translation buffer at this
// time as we only invalidated a prototype PTE.
//
}
//
// Change the page location to inactive (from active and valid).
//
Pfn1->u3.e1.PageLocation = TransitionPage;
//
// Decrement the reference count as the share count is now zero.
//
MM_PFN_LOCK_ASSERT();
ASSERT (Pfn1->u3.e2.ReferenceCount != 0);
if (Pfn1->u3.e2.ReferenceCount == 1) {
if (MI_IS_PFN_DELETED (Pfn1)) {
Pfn1->u3.e2.ReferenceCount = 0;
//
// There is no referenced PTE for this page, delete the page
// file space (if any), and place the page on the free list.
//
ASSERT (Pfn1->OriginalPte.u.Soft.Prototype == 0);
FreeBit = GET_PAGING_FILE_OFFSET (Pfn1->OriginalPte);
if ((FreeBit != 0) && (FreeBit != MI_PTE_LOOKUP_NEEDED)) {
MiReleaseConfirmedPageFileSpace (Pfn1->OriginalPte);
}
//
// Temporarily mark the frame as active and valid so that
// MiIdentifyPfn knows it is safe to walk back through the
// containing frames for a more accurate identification.
// Note the page will be immediately re-marked as it is
// inserted into the freelist.
//
Pfn1->u3.e1.PageLocation = ActiveAndValid;
MiInsertPageInFreeList (PageFrameIndex);
}
else {
MiDecrementReferenceCount (Pfn1, PageFrameIndex);
}
}
else {
InterlockedDecrementPfn ((PSHORT)&Pfn1->u3.e2.ReferenceCount);
}
}
return;
}
