640 lines
16 KiB
C
640 lines
16 KiB
C
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/*++
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Copyright (c) 1998 Microsoft Corporation
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Module Name:
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paesup.c
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Abstract:
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This module contains the machine dependent support for the x86 PAE
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architecture.
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Author:
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Landy Wang (landyw) 15-Nov-1998
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Revision History:
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--*/
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#include "mi.h"
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#if defined (_X86PAE_)
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#define PAES_PER_PAGE (PAGE_SIZE / sizeof(PAE_ENTRY))
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#define MINIMUM_PAE_SLIST_THRESHOLD (PAES_PER_PAGE * 1)
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#define MINIMUM_PAE_THRESHOLD (PAES_PER_PAGE * 4)
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#define REPLENISH_PAE_SIZE (PAES_PER_PAGE * 16)
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#define EXCESS_PAE_THRESHOLD (PAES_PER_PAGE * 20)
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#define MM_HIGHEST_PAE_PAGE 0xFFFFF
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ULONG MiFreePaeEntries;
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PAE_ENTRY MiFirstFreePae;
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LONG MmAllocatedPaePages;
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KSPIN_LOCK MiPaeLock;
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SLIST_HEADER MiPaeEntrySList;
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PAE_ENTRY MiSystemPaeVa;
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LONG
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MiPaeAllocatePages (
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VOID
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);
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VOID
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MiPaeFreePages (
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PVOID VirtualAddress
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);
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#pragma alloc_text(INIT,MiPaeInitialize)
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#pragma alloc_text(PAGE,MiPaeFreePages)
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VOID
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MiMarkMdlPageAttributes (
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IN PMDL Mdl,
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IN PFN_NUMBER NumberOfPages,
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IN MI_PFN_CACHE_ATTRIBUTE CacheAttribute
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);
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VOID
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MiPaeInitialize (
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VOID
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)
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{
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InitializeSListHead (&MiPaeEntrySList);
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KeInitializeSpinLock (&MiPaeLock);
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InitializeListHead (&MiFirstFreePae.PaeEntry.ListHead);
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}
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ULONG
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MiPaeAllocate (
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OUT PPAE_ENTRY *Va
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)
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/*++
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Routine Description:
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This routine allocates the top level page directory pointer structure.
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This structure will contain 4 PDPTEs.
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Arguments:
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Va - Supplies a place to put the virtual address this page can be accessed
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at.
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Return Value:
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Returns a virtual and physical address suitable for use as a top
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level page directory pointer page. The page returned must be below
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physical 4GB as required by the processor.
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Returns 0 if no page was allocated.
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Environment:
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Kernel mode. No locks may be held.
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--*/
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{
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LOGICAL FlushedOnce;
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PPAE_ENTRY Pae2;
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PPAE_ENTRY Pae3;
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PPAE_ENTRY Pae3Base;
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PPAE_ENTRY Pae;
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PPAE_ENTRY PaeBase;
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PFN_NUMBER PageFrameIndex;
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PSINGLE_LIST_ENTRY SingleListEntry;
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ULONG j;
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ULONG Entries;
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KLOCK_QUEUE_HANDLE LockHandle;
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#if DBG
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PMMPFN Pfn1;
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#endif
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FlushedOnce = FALSE;
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ASSERT (KeGetCurrentIrql() <= APC_LEVEL);
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do {
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//
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// Pop an entry from the freelist.
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//
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SingleListEntry = InterlockedPopEntrySList (&MiPaeEntrySList);
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if (SingleListEntry != NULL) {
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Pae = CONTAINING_RECORD (SingleListEntry,
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PAE_ENTRY,
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NextPae);
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PaeBase = (PPAE_ENTRY)PAGE_ALIGN(Pae);
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*Va = Pae;
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PageFrameIndex = PaeBase->PaeEntry.PageFrameNumber;
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ASSERT (PageFrameIndex <= MM_HIGHEST_PAE_PAGE);
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return (PageFrameIndex << PAGE_SHIFT) + BYTE_OFFSET (Pae);
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}
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KeAcquireInStackQueuedSpinLock (&MiPaeLock, &LockHandle);
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if (MiFreePaeEntries != 0) {
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ASSERT (IsListEmpty (&MiFirstFreePae.PaeEntry.ListHead) == 0);
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Pae = (PPAE_ENTRY) RemoveHeadList (&MiFirstFreePae.PaeEntry.ListHead);
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PaeBase = (PPAE_ENTRY)PAGE_ALIGN(Pae);
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PaeBase->PaeEntry.EntriesInUse += 1;
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#if DBG
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RtlZeroMemory ((PVOID)Pae, sizeof(PAE_ENTRY));
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Pfn1 = MI_PFN_ELEMENT (PaeBase->PaeEntry.PageFrameNumber);
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ASSERT (Pfn1->u2.ShareCount == 1);
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ASSERT (Pfn1->u3.e2.ReferenceCount == 1);
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ASSERT (Pfn1->u3.e1.PageLocation == ActiveAndValid);
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ASSERT (Pfn1->u3.e1.CacheAttribute == MiCached);
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#endif
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MiFreePaeEntries -= 1;
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//
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// Since we're holding the spinlock, dequeue a chain of entries
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// for the SLIST.
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//
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Entries = MiFreePaeEntries;
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if (Entries != 0) {
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if (Entries > MINIMUM_PAE_SLIST_THRESHOLD) {
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Entries = MINIMUM_PAE_SLIST_THRESHOLD;
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}
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ASSERT (IsListEmpty (&MiFirstFreePae.PaeEntry.ListHead) == 0);
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Pae2 = (PPAE_ENTRY) RemoveHeadList (&MiFirstFreePae.PaeEntry.ListHead);
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Pae2->NextPae.Next = NULL;
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Pae3 = Pae2;
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Pae3Base = (PPAE_ENTRY)PAGE_ALIGN(Pae3);
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Pae3Base->PaeEntry.EntriesInUse += 1;
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for (j = 1; j < Entries; j += 1) {
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ASSERT (IsListEmpty (&MiFirstFreePae.PaeEntry.ListHead) == 0);
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Pae3->NextPae.Next = (PSINGLE_LIST_ENTRY) RemoveHeadList (&MiFirstFreePae.PaeEntry.ListHead);
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Pae3 = (PPAE_ENTRY) Pae3->NextPae.Next;
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Pae3Base = (PPAE_ENTRY)PAGE_ALIGN(Pae3);
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Pae3Base->PaeEntry.EntriesInUse += 1;
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}
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MiFreePaeEntries -= Entries;
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KeReleaseInStackQueuedSpinLock (&LockHandle);
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Pae3->NextPae.Next = NULL;
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InterlockedPushListSList (&MiPaeEntrySList,
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(PSINGLE_LIST_ENTRY) Pae2,
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(PSINGLE_LIST_ENTRY) Pae3,
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Entries);
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}
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else {
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KeReleaseInStackQueuedSpinLock (&LockHandle);
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}
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ASSERT (KeGetCurrentIrql() <= APC_LEVEL);
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*Va = Pae;
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PageFrameIndex = PaeBase->PaeEntry.PageFrameNumber;
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ASSERT (PageFrameIndex <= MM_HIGHEST_PAE_PAGE);
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return (PageFrameIndex << PAGE_SHIFT) + BYTE_OFFSET (Pae);
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}
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KeReleaseInStackQueuedSpinLock (&LockHandle);
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if (FlushedOnce == TRUE) {
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break;
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}
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//
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// No free pages in the cachelist, replenish the list now.
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//
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if (MiPaeAllocatePages () == 0) {
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InterlockedIncrement (&MiDelayPageFaults);
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//
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// Attempt to move pages to the standby list.
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//
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MmEmptyAllWorkingSets ();
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MiFlushAllPages();
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KeDelayExecutionThread (KernelMode,
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FALSE,
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(PLARGE_INTEGER)&MmHalfSecond);
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InterlockedDecrement (&MiDelayPageFaults);
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FlushedOnce = TRUE;
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//
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// Since all the working sets have been trimmed, check whether
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// another thread has replenished our list. If not, then attempt
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// to do so since the working set pain has already been absorbed.
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//
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if (MiFreePaeEntries < MINIMUM_PAE_THRESHOLD) {
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MiPaeAllocatePages ();
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}
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}
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} while (TRUE);
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ASSERT (KeGetCurrentIrql() <= APC_LEVEL);
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return 0;
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}
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VOID
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MiPaeFree (
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PPAE_ENTRY Pae
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)
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/*++
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Routine Description:
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This routine releases the top level page directory pointer page.
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Arguments:
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PageFrameIndex - Supplies the top level page directory pointer page.
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Return Value:
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None.
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Environment:
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Kernel mode. No locks may be held.
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--*/
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{
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ULONG i;
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PLIST_ENTRY NextEntry;
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PPAE_ENTRY PaeBase;
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KLOCK_QUEUE_HANDLE LockHandle;
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#if DBG
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PMMPTE PointerPte;
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PFN_NUMBER PageFrameIndex;
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PMMPFN Pfn1;
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PointerPte = MiGetPteAddress (Pae);
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PageFrameIndex = MI_GET_PAGE_FRAME_FROM_PTE (PointerPte);
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//
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// This page must be in the first 4GB of RAM.
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//
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ASSERT (PageFrameIndex <= MM_HIGHEST_PAE_PAGE);
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Pfn1 = MI_PFN_ELEMENT (PageFrameIndex);
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ASSERT (Pfn1->u2.ShareCount == 1);
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ASSERT (Pfn1->u3.e2.ReferenceCount == 1);
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ASSERT (Pfn1->u3.e1.PageLocation == ActiveAndValid);
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ASSERT (Pfn1->u3.e1.CacheAttribute == MiCached);
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#endif
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if (ExQueryDepthSList (&MiPaeEntrySList) < MINIMUM_PAE_SLIST_THRESHOLD) {
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InterlockedPushEntrySList (&MiPaeEntrySList, &Pae->NextPae);
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return;
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}
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PaeBase = (PPAE_ENTRY)PAGE_ALIGN(Pae);
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KeAcquireInStackQueuedSpinLock (&MiPaeLock, &LockHandle);
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PaeBase->PaeEntry.EntriesInUse -= 1;
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if ((PaeBase->PaeEntry.EntriesInUse == 0) &&
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(MiFreePaeEntries > EXCESS_PAE_THRESHOLD)) {
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//
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// Free the entire page.
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//
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i = 1;
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NextEntry = MiFirstFreePae.PaeEntry.ListHead.Flink;
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while (NextEntry != &MiFirstFreePae.PaeEntry.ListHead) {
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Pae = CONTAINING_RECORD (NextEntry,
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PAE_ENTRY,
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PaeEntry.ListHead);
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if (PAGE_ALIGN(Pae) == PaeBase) {
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RemoveEntryList (NextEntry);
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i += 1;
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}
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NextEntry = Pae->PaeEntry.ListHead.Flink;
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}
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ASSERT (i == PAES_PER_PAGE - 1);
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MiFreePaeEntries -= (PAES_PER_PAGE - 1);
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KeReleaseInStackQueuedSpinLock (&LockHandle);
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MiPaeFreePages (PaeBase);
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}
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else {
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InsertTailList (&MiFirstFreePae.PaeEntry.ListHead,
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&Pae->PaeEntry.ListHead);
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MiFreePaeEntries += 1;
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KeReleaseInStackQueuedSpinLock (&LockHandle);
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}
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return;
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}
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LONG
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MiPaeAllocatePages (
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VOID
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)
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/*++
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Routine Description:
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This routine replenishes the PAE top level mapping list.
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Arguments:
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None.
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Return Value:
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The number of pages allocated.
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Environment:
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Kernel mode, IRQL of APC_LEVEL or below.
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--*/
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{
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PMDL MemoryDescriptorList;
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LONG AllocatedPaePages;
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ULONG i;
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ULONG j;
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PPFN_NUMBER SlidePage;
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PPFN_NUMBER Page;
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PFN_NUMBER PageFrameIndex;
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ULONG_PTR ActualPages;
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PMMPTE PointerPte;
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PVOID BaseAddress;
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PPAE_ENTRY Pae;
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ULONG NumberOfPages;
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MMPTE TempPte;
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PHYSICAL_ADDRESS HighAddress;
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PHYSICAL_ADDRESS LowAddress;
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PHYSICAL_ADDRESS SkipBytes;
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KLOCK_QUEUE_HANDLE LockHandle;
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#if defined (_MI_MORE_THAN_4GB_)
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if (MiNoLowMemory != 0) {
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BaseAddress = MiAllocateLowMemory (PAGE_SIZE,
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0,
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MiNoLowMemory - 1,
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0,
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(PVOID)0x123,
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MmCached,
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'DeaP');
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if (BaseAddress == NULL) {
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return 0;
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}
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PageFrameIndex = MI_GET_PAGE_FRAME_FROM_PTE (MiGetPteAddress(BaseAddress));
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Pae = (PPAE_ENTRY) BaseAddress;
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Pae->PaeEntry.EntriesInUse = 0;
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Pae->PaeEntry.PageFrameNumber = PageFrameIndex;
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Pae += 1;
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KeAcquireInStackQueuedSpinLock (&MiPaeLock, &LockHandle);
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for (i = 1; i < PAES_PER_PAGE; i += 1) {
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InsertTailList (&MiFirstFreePae.PaeEntry.ListHead,
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&Pae->PaeEntry.ListHead);
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Pae += 1;
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}
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MiFreePaeEntries += (PAES_PER_PAGE - 1);
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KeReleaseInStackQueuedSpinLock (&LockHandle);
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InterlockedIncrement (&MmAllocatedPaePages);
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return 1;
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}
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#endif
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NumberOfPages = REPLENISH_PAE_SIZE / PAES_PER_PAGE;
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AllocatedPaePages = 0;
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HighAddress.QuadPart = (ULONGLONG)_4gb - 1;
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LowAddress.QuadPart = 0;
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SkipBytes.QuadPart = 0;
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//
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// This is a potentially expensive call so pick up a chunk of pages
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// at once to amortize the cost.
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//
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MemoryDescriptorList = MmAllocatePagesForMdl (LowAddress,
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HighAddress,
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SkipBytes,
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NumberOfPages << PAGE_SHIFT);
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if (MemoryDescriptorList == NULL) {
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return 0;
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}
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ActualPages = MemoryDescriptorList->ByteCount >> PAGE_SHIFT;
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MiMarkMdlPageAttributes (MemoryDescriptorList, ActualPages, MiCached);
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TempPte = ValidKernelPte;
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Page = (PPFN_NUMBER)(MemoryDescriptorList + 1);
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//
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// Map each page individually as they may need to be freed individually
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// later.
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//
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for (i = 0; i < ActualPages; i += 1) {
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PageFrameIndex = *Page;
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PointerPte = MiReserveSystemPtes (1, SystemPteSpace);
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||
|
if (PointerPte == NULL) {
|
||
|
|
||
|
//
|
||
|
// Free any remaining pages in the MDL as they are not mapped.
|
||
|
// Slide the MDL pages forward so the mapped ones are kept.
|
||
|
//
|
||
|
|
||
|
MmInitializeMdl (MemoryDescriptorList,
|
||
|
0,
|
||
|
(ActualPages - i) << PAGE_SHIFT);
|
||
|
|
||
|
SlidePage = (PPFN_NUMBER)(MemoryDescriptorList + 1);
|
||
|
|
||
|
while (i < ActualPages) {
|
||
|
i += 1;
|
||
|
*SlidePage = *Page;
|
||
|
SlidePage += 1;
|
||
|
Page += 1;
|
||
|
}
|
||
|
|
||
|
MmFreePagesFromMdl (MemoryDescriptorList);
|
||
|
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
TempPte.u.Hard.PageFrameNumber = PageFrameIndex;
|
||
|
MI_WRITE_VALID_PTE (PointerPte, TempPte);
|
||
|
|
||
|
BaseAddress = MiGetVirtualAddressMappedByPte (PointerPte);
|
||
|
|
||
|
Pae = (PPAE_ENTRY) BaseAddress;
|
||
|
|
||
|
Pae->PaeEntry.EntriesInUse = 0;
|
||
|
Pae->PaeEntry.PageFrameNumber = PageFrameIndex;
|
||
|
Pae += 1;
|
||
|
|
||
|
//
|
||
|
// Put the first chunk into the SLIST if it's still low, and just
|
||
|
// enqueue all the other entries normally.
|
||
|
//
|
||
|
|
||
|
if ((i == 0) &&
|
||
|
(ExQueryDepthSList (&MiPaeEntrySList) < MINIMUM_PAE_SLIST_THRESHOLD)) {
|
||
|
|
||
|
(Pae - 1)->PaeEntry.EntriesInUse = PAES_PER_PAGE - 1;
|
||
|
|
||
|
for (j = 1; j < PAES_PER_PAGE - 1; j += 1) {
|
||
|
Pae->NextPae.Next = (PSINGLE_LIST_ENTRY) (Pae + 1);
|
||
|
Pae += 1;
|
||
|
}
|
||
|
|
||
|
Pae->NextPae.Next = NULL;
|
||
|
|
||
|
InterlockedPushListSList (&MiPaeEntrySList,
|
||
|
(PSINGLE_LIST_ENTRY)((PPAE_ENTRY) BaseAddress + 1),
|
||
|
(PSINGLE_LIST_ENTRY) Pae,
|
||
|
PAES_PER_PAGE - 1);
|
||
|
}
|
||
|
else {
|
||
|
|
||
|
KeAcquireInStackQueuedSpinLock (&MiPaeLock, &LockHandle);
|
||
|
|
||
|
for (j = 1; j < PAES_PER_PAGE; j += 1) {
|
||
|
InsertTailList (&MiFirstFreePae.PaeEntry.ListHead,
|
||
|
&Pae->PaeEntry.ListHead);
|
||
|
Pae += 1;
|
||
|
}
|
||
|
|
||
|
MiFreePaeEntries += (PAES_PER_PAGE - 1);
|
||
|
|
||
|
KeReleaseInStackQueuedSpinLock (&LockHandle);
|
||
|
}
|
||
|
|
||
|
AllocatedPaePages += 1;
|
||
|
|
||
|
Page += 1;
|
||
|
}
|
||
|
|
||
|
ExFreePool (MemoryDescriptorList);
|
||
|
|
||
|
InterlockedExchangeAdd (&MmAllocatedPaePages, AllocatedPaePages);
|
||
|
|
||
|
return AllocatedPaePages;
|
||
|
}
|
||
|
|
||
|
VOID
|
||
|
MiPaeFreePages (
|
||
|
PVOID VirtualAddress
|
||
|
)
|
||
|
|
||
|
/*++
|
||
|
|
||
|
Routine Description:
|
||
|
|
||
|
This routine releases a single page that previously contained top level
|
||
|
page directory pointer pages.
|
||
|
|
||
|
Arguments:
|
||
|
|
||
|
VirtualAddress - Supplies the virtual address of the page that contained
|
||
|
top level page directory pointer pages.
|
||
|
|
||
|
Return Value:
|
||
|
|
||
|
None.
|
||
|
|
||
|
Environment:
|
||
|
|
||
|
Kernel mode. No locks held.
|
||
|
|
||
|
--*/
|
||
|
|
||
|
{
|
||
|
ULONG MdlPages;
|
||
|
PFN_NUMBER PageFrameIndex;
|
||
|
PMMPTE PointerPte;
|
||
|
PFN_NUMBER MdlHack[(sizeof(MDL) / sizeof(PFN_NUMBER)) + 1];
|
||
|
PPFN_NUMBER MdlPage;
|
||
|
PMDL MemoryDescriptorList;
|
||
|
|
||
|
#if defined (_MI_MORE_THAN_4GB_)
|
||
|
if (MiNoLowMemory != 0) {
|
||
|
if (MiFreeLowMemory (VirtualAddress, 'DeaP') == TRUE) {
|
||
|
InterlockedDecrement (&MmAllocatedPaePages);
|
||
|
return;
|
||
|
}
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
MemoryDescriptorList = (PMDL)&MdlHack[0];
|
||
|
MdlPages = 1;
|
||
|
MmInitializeMdl (MemoryDescriptorList, 0, MdlPages << PAGE_SHIFT);
|
||
|
|
||
|
MdlPage = (PPFN_NUMBER)(MemoryDescriptorList + 1);
|
||
|
|
||
|
PointerPte = MiGetPteAddress (VirtualAddress);
|
||
|
PageFrameIndex = MI_GET_PAGE_FRAME_FROM_PTE (PointerPte);
|
||
|
*MdlPage = PageFrameIndex;
|
||
|
|
||
|
ASSERT ((MI_PFN_ELEMENT(PageFrameIndex))->u3.e1.CacheAttribute == MiCached);
|
||
|
|
||
|
MiReleaseSystemPtes (PointerPte, 1, SystemPteSpace);
|
||
|
|
||
|
MmFreePagesFromMdl (MemoryDescriptorList);
|
||
|
|
||
|
InterlockedDecrement (&MmAllocatedPaePages);
|
||
|
}
|
||
|
|
||
|
#endif
|