Exemplo n.º 1
0
BOOLEAN
MmCreateProcessAddressSpace (
    IN ULONG MinimumWorkingSetSize,
    IN PEPROCESS NewProcess,
    OUT PULONG_PTR DirectoryTableBase
    )

/*++

Routine Description:

    This routine creates an address space which maps the system
    portion and contains a hyper space entry.

Arguments:

    MinimumWorkingSetSize - Supplies the minimum working set size for
                            this address space.  This value is only used
                            to ensure that ample physical pages exist
                            to create this process.

    NewProcess - Supplies a pointer to the process object being created.

    DirectoryTableBase - Returns the value of the newly created
                         address space's Page Directory (PD) page and
                         hyper space page.

Return Value:

    Returns TRUE if an address space was successfully created, FALSE
    if ample physical pages do not exist.

Environment:

    Kernel mode.  APCs Disabled.

--*/

{
    LOGICAL FlushTbNeeded;
    PFN_NUMBER PageDirectoryIndex;
    PFN_NUMBER HyperSpaceIndex;
    PFN_NUMBER PageContainingWorkingSet;
    PFN_NUMBER VadBitMapPage;
    MMPTE TempPte;
    MMPTE TempPte2;
    PEPROCESS CurrentProcess;
    KIRQL OldIrql;
    PMMPFN Pfn1;
    ULONG Color;
    PMMPTE PointerPte;
    ULONG PdeOffset;
    PMMPTE MappingPte;
    PMMPTE PointerFillPte;
    PMMPTE CurrentAddressSpacePde;

    //
    // Charge commitment for the page directory pages, working set page table
    // page, and working set list.  If Vad bitmap lookups are enabled, then
    // charge for a page or two for that as well.
    //

    if (MiChargeCommitment (MM_PROCESS_COMMIT_CHARGE, NULL) == FALSE) {
        return FALSE;
    }

    FlushTbNeeded = FALSE;
    CurrentProcess = PsGetCurrentProcess ();

    NewProcess->NextPageColor = (USHORT) (RtlRandom (&MmProcessColorSeed));
    KeInitializeSpinLock (&NewProcess->HyperSpaceLock);

    //
    // Get the PFN lock to get physical pages.
    //

    LOCK_PFN (OldIrql);

    //
    // Check to make sure the physical pages are available.
    //

    if (MI_NONPAGEABLE_MEMORY_AVAILABLE() <= (SPFN_NUMBER)MinimumWorkingSetSize){

        UNLOCK_PFN (OldIrql);
        MiReturnCommitment (MM_PROCESS_COMMIT_CHARGE);

        //
        // Indicate no directory base was allocated.
        //

        return FALSE;
    }

    MM_TRACK_COMMIT (MM_DBG_COMMIT_PROCESS_CREATE, MM_PROCESS_COMMIT_CHARGE);

    MI_DECREMENT_RESIDENT_AVAILABLE (MinimumWorkingSetSize,
                                     MM_RESAVAIL_ALLOCATE_CREATE_PROCESS);

    //
    // Allocate a page directory page.
    //

    if (MmAvailablePages < MM_HIGH_LIMIT) {
        MiEnsureAvailablePageOrWait (NULL, OldIrql);
    }

    Color =  MI_PAGE_COLOR_PTE_PROCESS (PDE_BASE,
                                        &CurrentProcess->NextPageColor);

    PageDirectoryIndex = MiRemoveZeroPageMayReleaseLocks (Color, OldIrql);

    Pfn1 = MI_PFN_ELEMENT (PageDirectoryIndex);

    if (Pfn1->u3.e1.CacheAttribute != MiCached) {
        Pfn1->u3.e1.CacheAttribute = MiCached;
        FlushTbNeeded = TRUE;
    }

    //
    // Allocate the hyper space page table page.
    //

    if (MmAvailablePages < MM_HIGH_LIMIT) {
        MiEnsureAvailablePageOrWait (NULL, OldIrql);
    }

    Color = MI_PAGE_COLOR_PTE_PROCESS (MiGetPdeAddress(HYPER_SPACE),
                                       &CurrentProcess->NextPageColor);

    HyperSpaceIndex = MiRemoveZeroPageMayReleaseLocks (Color, OldIrql);

    Pfn1 = MI_PFN_ELEMENT (HyperSpaceIndex);

    if (Pfn1->u3.e1.CacheAttribute != MiCached) {
        Pfn1->u3.e1.CacheAttribute = MiCached;
        FlushTbNeeded = TRUE;
    }

    //
    // Remove page(s) for the VAD bitmap.
    //

    if (MmAvailablePages < MM_HIGH_LIMIT) {
        MiEnsureAvailablePageOrWait (NULL, OldIrql);
    }

    Color = MI_PAGE_COLOR_VA_PROCESS (MmWorkingSetList,
                                      &CurrentProcess->NextPageColor);

    VadBitMapPage = MiRemoveZeroPageMayReleaseLocks (Color, OldIrql);

    Pfn1 = MI_PFN_ELEMENT (VadBitMapPage);

    if (Pfn1->u3.e1.CacheAttribute != MiCached) {
        Pfn1->u3.e1.CacheAttribute = MiCached;
        FlushTbNeeded = TRUE;
    }

    //
    // Remove a page for the working set list.
    //

    if (MmAvailablePages < MM_HIGH_LIMIT) {
        MiEnsureAvailablePageOrWait (NULL, OldIrql);
    }

    Color = MI_PAGE_COLOR_VA_PROCESS (MmWorkingSetList,
                                      &CurrentProcess->NextPageColor);

    PageContainingWorkingSet = MiRemoveZeroPageMayReleaseLocks (Color, OldIrql);

    Pfn1 = MI_PFN_ELEMENT (PageContainingWorkingSet);

    if (Pfn1->u3.e1.CacheAttribute != MiCached) {
        Pfn1->u3.e1.CacheAttribute = MiCached;
        FlushTbNeeded = TRUE;
    }

    UNLOCK_PFN (OldIrql);

    if (FlushTbNeeded == TRUE) {
        MI_FLUSH_TB_FOR_CACHED_ATTRIBUTE ();
    }

    ASSERT (NewProcess->AddressSpaceInitialized == 0);
    PS_SET_BITS (&NewProcess->Flags, PS_PROCESS_FLAGS_ADDRESS_SPACE1);
    ASSERT (NewProcess->AddressSpaceInitialized == 1);

    NewProcess->Vm.MinimumWorkingSetSize = MinimumWorkingSetSize;

    NewProcess->WorkingSetPage = PageContainingWorkingSet;

    INITIALIZE_DIRECTORY_TABLE_BASE (&DirectoryTableBase[0], PageDirectoryIndex);

    INITIALIZE_DIRECTORY_TABLE_BASE (&DirectoryTableBase[1], HyperSpaceIndex);

    //
    // Initialize the page reserved for hyper space.
    //

    TempPte = ValidPdePde;
    MI_SET_GLOBAL_STATE (TempPte, 0);

    MappingPte = MiReserveSystemPtes (1, SystemPteSpace);

    if (MappingPte != NULL) {

        MI_MAKE_VALID_KERNEL_PTE (TempPte2,
                                  HyperSpaceIndex,
                                  MM_READWRITE,
                                  MappingPte);

        MI_SET_PTE_DIRTY (TempPte2);

        MI_WRITE_VALID_PTE (MappingPte, TempPte2);

        PointerPte = MiGetVirtualAddressMappedByPte (MappingPte);
    }
    else {
        PointerPte = MiMapPageInHyperSpace (CurrentProcess, HyperSpaceIndex, &OldIrql);
    }

    TempPte.u.Hard.PageFrameNumber = VadBitMapPage;
    PointerPte[MiGetPteOffset(VAD_BITMAP_SPACE)] = TempPte;

    TempPte.u.Hard.PageFrameNumber = PageContainingWorkingSet;
    PointerPte[MiGetPteOffset(MmWorkingSetList)] = TempPte;

    if (MappingPte != NULL) {
        MiReleaseSystemPtes (MappingPte, 1, SystemPteSpace);
    }
    else {
        MiUnmapPageInHyperSpace (CurrentProcess, PointerPte, OldIrql);
    }

    //
    // Set the PTE address in the PFN for the page directory page.
    //

    Pfn1 = MI_PFN_ELEMENT (PageDirectoryIndex);

    Pfn1->PteAddress = (PMMPTE)PDE_BASE;

    TempPte = ValidPdePde;
    TempPte.u.Hard.PageFrameNumber = HyperSpaceIndex;
    MI_SET_GLOBAL_STATE (TempPte, 0);

    //
    // Add the new process to our internal list prior to filling any
    // system PDEs so if a system PDE changes (large page map or unmap)
    // it can mark this process for a subsequent update.
    //

    ASSERT (NewProcess->Pcb.DirectoryTableBase[0] == 0);

    LOCK_EXPANSION (OldIrql);

    InsertTailList (&MmProcessList, &NewProcess->MmProcessLinks);

    UNLOCK_EXPANSION (OldIrql);

    //
    // Map the page directory page in hyperspace.
    //

    MappingPte = MiReserveSystemPtes (1, SystemPteSpace);

    if (MappingPte != NULL) {

        MI_MAKE_VALID_KERNEL_PTE (TempPte2,
                                  PageDirectoryIndex,
                                  MM_READWRITE,
                                  MappingPte);

        MI_SET_PTE_DIRTY (TempPte2);

        MI_WRITE_VALID_PTE (MappingPte, TempPte2);

        PointerPte = MiGetVirtualAddressMappedByPte (MappingPte);
    }
    else {
        PointerPte = MiMapPageInHyperSpace (CurrentProcess, PageDirectoryIndex, &OldIrql);
    }

    PdeOffset = MiGetPdeOffset (MmSystemRangeStart);
    PointerFillPte = &PointerPte[PdeOffset];
    CurrentAddressSpacePde = MiGetPdeAddress (MmSystemRangeStart);

    RtlCopyMemory (PointerFillPte,
                   CurrentAddressSpacePde,
                   PAGE_SIZE - PdeOffset * sizeof (MMPTE));

    //
    // Map the working set page table page.
    //

    PdeOffset = MiGetPdeOffset (HYPER_SPACE);
    PointerPte[PdeOffset] = TempPte;

    //
    // Zero the remaining page directory range used to map the working
    // set list and its hash.
    //

    PdeOffset += 1;
    ASSERT (MiGetPdeOffset (MmHyperSpaceEnd) >= PdeOffset);

    MiZeroMemoryPte (&PointerPte[PdeOffset],
                     (MiGetPdeOffset (MmHyperSpaceEnd) - PdeOffset + 1));

    //
    // Recursively map the page directory page so it points to itself.
    //

    TempPte.u.Hard.PageFrameNumber = PageDirectoryIndex;
    PointerPte[MiGetPdeOffset(PTE_BASE)] = TempPte;

    if (MappingPte != NULL) {
        MiReleaseSystemPtes (MappingPte, 1, SystemPteSpace);
    }
    else {
        MiUnmapPageInHyperSpace (CurrentProcess, PointerPte, OldIrql);
    }

    InterlockedExchangeAddSizeT (&MmProcessCommit, MM_PROCESS_COMMIT_CHARGE);

    //
    // Up the session space reference count.
    //

    MiSessionAddProcess (NewProcess);

    return TRUE;
}
Exemplo n.º 2
0
NTSTATUS
MiCcPutPagesInTransition (
    IN PMI_READ_INFO MiReadInfo
    )

/*++

Routine Description:

    This routine allocates physical memory for the specified read-list and
    puts all the pages in transition (so collided faults from other threads
    for these same pages remain coherent).  I/O for any pages not already
    resident are issued here.  The caller must wait for their completion.

Arguments:

    MiReadInfo - Supplies a pointer to the read-list.

Return Value:

    STATUS_SUCCESS - all the pages were already resident, reference counts
                     have been applied and no I/O needs to be waited for.

    STATUS_ISSUE_PAGING_IO - the I/O has been issued and the caller must wait.

    Various other failure status values indicate the operation failed.

Environment:

    Kernel mode. PASSIVE_LEVEL.

--*/

{
    NTSTATUS status;
    PMMPTE LocalPrototypePte;
    PVOID StartingVa;
    PFN_NUMBER MdlPages;
    KIRQL OldIrql;
    MMPTE PteContents;
    PFN_NUMBER PageFrameIndex;
    PFN_NUMBER ResidentAvailableCharge;
    PPFN_NUMBER IoPage;
    PPFN_NUMBER ApiPage;
    PPFN_NUMBER Page;
    PPFN_NUMBER DestinationPage;
    ULONG PageColor;
    PMMPTE PointerPte;
    PMMPTE *ProtoPteArray;
    PMMPTE *EndProtoPteArray;
    PFN_NUMBER DummyPage;
    PMDL Mdl;
    PMDL FreeMdl;
    PMMPFN PfnProto;
    PMMPFN Pfn1;
    PMMPFN DummyPfn1;
    ULONG i;
    PFN_NUMBER DummyTrim;
    ULONG NumberOfPagesNeedingIo;
    MMPTE TempPte;
    PMMPTE PointerPde;
    PEPROCESS CurrentProcess;
    PMMINPAGE_SUPPORT InPageSupport;
    PKPRCB Prcb;

    ASSERT (KeGetCurrentIrql() == PASSIVE_LEVEL);

    MiReadInfo->DummyPagePfn = NULL;

    FreeMdl = NULL;
    CurrentProcess = PsGetCurrentProcess();

    PfnProto = NULL;
    PointerPde = NULL;

    InPageSupport = MiReadInfo->InPageSupport;
    
    Mdl = MI_EXTRACT_PREFETCH_MDL (InPageSupport);
    ASSERT (Mdl == MiReadInfo->IoMdl);

    IoPage = (PPFN_NUMBER)(Mdl + 1);
    ApiPage = (PPFN_NUMBER)(MiReadInfo->ApiMdl + 1);

    StartingVa = (PVOID)((PCHAR)Mdl->StartVa + Mdl->ByteOffset);
    
    MdlPages = ADDRESS_AND_SIZE_TO_SPAN_PAGES (StartingVa,
                                               Mdl->ByteCount);

    if (MdlPages + 1 > MAXUSHORT) {

        //
        // The PFN ReferenceCount for the dummy page could wrap, refuse the
        // request.
        //

        return STATUS_INSUFFICIENT_RESOURCES;
    }

    NumberOfPagesNeedingIo = 0;

    ProtoPteArray = (PMMPTE *)InPageSupport->BasePte;
    EndProtoPteArray = ProtoPteArray + MdlPages;

    ASSERT (*ProtoPteArray != NULL);

    LOCK_PFN (OldIrql);

    //
    // Ensure sufficient pages exist for the transfer plus the dummy page.
    //

    if (((SPFN_NUMBER)MdlPages > (SPFN_NUMBER)(MmAvailablePages - MM_HIGH_LIMIT)) ||
        (MI_NONPAGEABLE_MEMORY_AVAILABLE() <= (SPFN_NUMBER)MdlPages)) {

        UNLOCK_PFN (OldIrql);

        return STATUS_INSUFFICIENT_RESOURCES;
    }

    //
    // Charge resident available immediately as the PFN lock may get released
    // and reacquired below before all the pages have been locked down.
    // Note the dummy page is immediately charged separately.
    //

    MI_DECREMENT_RESIDENT_AVAILABLE (MdlPages, MM_RESAVAIL_ALLOCATE_BUILDMDL);

    ResidentAvailableCharge = MdlPages;

    //
    // Allocate a dummy page to map discarded pages that aren't skipped.
    //

    DummyPage = MiRemoveAnyPage (0);
    Pfn1 = MI_PFN_ELEMENT (DummyPage);

    ASSERT (Pfn1->u2.ShareCount == 0);
    ASSERT (Pfn1->u3.e2.ReferenceCount == 0);

    MiInitializePfnForOtherProcess (DummyPage, MI_PF_DUMMY_PAGE_PTE, 0);

    //
    // Give the page a containing frame so MiIdentifyPfn won't crash.
    //

    Pfn1->u4.PteFrame = PsInitialSystemProcess->Pcb.DirectoryTableBase[0] >> PAGE_SHIFT;

    //
    // Always bias the reference count by 1 and charge for this locked page
    // up front so the myriad increments and decrements don't get slowed
    // down with needless checking.
    //

    Pfn1->u3.e1.PrototypePte = 0;

    MI_ADD_LOCKED_PAGE_CHARGE (Pfn1);

    Pfn1->u3.e1.ReadInProgress = 1;

    MiReadInfo->DummyPagePfn = Pfn1;

    DummyPfn1 = Pfn1;

    DummyPfn1->u3.e2.ReferenceCount =
        (USHORT)(DummyPfn1->u3.e2.ReferenceCount + MdlPages);

    //
    // Properly initialize the inpage support block fields we overloaded.
    //

    InPageSupport->BasePte = *ProtoPteArray;

    //
    // Build the proper InPageSupport and MDL to describe this run.
    //

    for (; ProtoPteArray < EndProtoPteArray; ProtoPteArray += 1, IoPage += 1, ApiPage += 1) {
    
        //
        // Fill the MDL entry for this RLE.
        //
    
        PointerPte = *ProtoPteArray;

        ASSERT (PointerPte != NULL);

        //
        // The PointerPte better be inside a prototype PTE allocation
        // so that subsequent page trims update the correct PTEs.
        //

        ASSERT (((PointerPte >= (PMMPTE)MmPagedPoolStart) &&
                (PointerPte <= (PMMPTE)MmPagedPoolEnd)) ||
                ((PointerPte >= (PMMPTE)MmSpecialPoolStart) && (PointerPte <= (PMMPTE)MmSpecialPoolEnd)));

        //
        // Check the state of this prototype PTE now that the PFN lock is held.
        // If the page is not resident, the PTE must be put in transition with
        // read in progress before the PFN lock is released.
        //

        //
        // Lock page containing prototype PTEs in memory by
        // incrementing the reference count for the page.
        // Unlock any page locked earlier containing prototype PTEs if
        // the containing page is not the same for both.
        //

        if (PfnProto != NULL) {

            if (PointerPde != MiGetPteAddress (PointerPte)) {

                ASSERT (PfnProto->u3.e2.ReferenceCount > 1);
                MI_REMOVE_LOCKED_PAGE_CHARGE_AND_DECREF (PfnProto);
                PfnProto = NULL;
            }
        }

        if (PfnProto == NULL) {

            ASSERT (!MI_IS_PHYSICAL_ADDRESS (PointerPte));
   
            PointerPde = MiGetPteAddress (PointerPte);
 
            if (PointerPde->u.Hard.Valid == 0) {
                MiMakeSystemAddressValidPfn (PointerPte, OldIrql);
            }

            PfnProto = MI_PFN_ELEMENT (PointerPde->u.Hard.PageFrameNumber);
            MI_ADD_LOCKED_PAGE_CHARGE (PfnProto);
            ASSERT (PfnProto->u3.e2.ReferenceCount > 1);
        }

recheck:
        PteContents = *PointerPte;

        // LWFIX: are zero or dzero ptes possible here ?
        ASSERT (PteContents.u.Long != 0);

        if (PteContents.u.Hard.Valid == 1) {
            PageFrameIndex = MI_GET_PAGE_FRAME_FROM_PTE (&PteContents);
            Pfn1 = MI_PFN_ELEMENT (PageFrameIndex);
            ASSERT (Pfn1->u3.e1.PrototypePte == 1);
            MI_ADD_LOCKED_PAGE_CHARGE (Pfn1);
            *ApiPage = PageFrameIndex;
            *IoPage = DummyPage;
            continue;
        }

        if ((PteContents.u.Soft.Prototype == 0) &&
            (PteContents.u.Soft.Transition == 1)) {

            //
            // The page is in transition.  If there is an inpage still in
            // progress, wait for it to complete.  Reference the PFN and
            // then march on.
            //

            PageFrameIndex = MI_GET_PAGE_FRAME_FROM_TRANSITION_PTE (&PteContents);
            Pfn1 = MI_PFN_ELEMENT (PageFrameIndex);
            ASSERT (Pfn1->u3.e1.PrototypePte == 1);

            if (Pfn1->u4.InPageError) {

                //
                // There was an in-page read error and there are other
                // threads colliding for this page, delay to let the
                // other threads complete and then retry.
                //

                UNLOCK_PFN (OldIrql);
                KeDelayExecutionThread (KernelMode, FALSE, (PLARGE_INTEGER)&MmHalfSecond);
                LOCK_PFN (OldIrql);
                goto recheck;
            }

            if (Pfn1->u3.e1.ReadInProgress) {
                    // LWFIX - start with temp\aw.c
            }

            //
            // PTE refers to a normal transition PTE.
            //

            ASSERT ((SPFN_NUMBER)MmAvailablePages >= 0);

            if (MmAvailablePages == 0) {

                //
                // This can only happen if the system is utilizing a hardware
                // compression cache.  This ensures that only a safe amount
                // of the compressed virtual cache is directly mapped so that
                // if the hardware gets into trouble, we can bail it out.
                //

                UNLOCK_PFN (OldIrql);
                KeDelayExecutionThread (KernelMode, FALSE, (PLARGE_INTEGER)&MmHalfSecond);
                LOCK_PFN (OldIrql);
                goto recheck;
            }

            //
            // The PFN reference count will be 1 already here if the
            // modified writer has begun a write of this page.  Otherwise
            // it's ordinarily 0.
            //

            MI_ADD_LOCKED_PAGE_CHARGE_FOR_MODIFIED_PAGE (Pfn1);

            *IoPage = DummyPage;
            *ApiPage = PageFrameIndex;
            continue;
        }

        // LWFIX: need to handle protos that are now pagefile (or dzero)
        // backed - prefetching it from the file here would cause us to lose
        // the contents.  Note this can happen for session-space images
        // as we back modified (ie: for relocation fixups or IAT
        // updated) portions from the pagefile.  remove the assert below too.
        ASSERT (PteContents.u.Soft.Prototype == 1);

        if ((MmAvailablePages < MM_HIGH_LIMIT) &&
            (MiEnsureAvailablePageOrWait (NULL, OldIrql))) {

            //
            // Had to wait so recheck all state.
            //

            goto recheck;
        }

        NumberOfPagesNeedingIo += 1;

        //
        // Allocate a physical page.
        //

        PageColor = MI_PAGE_COLOR_VA_PROCESS (
                        MiGetVirtualAddressMappedByPte (PointerPte),
                        &CurrentProcess->NextPageColor);

        PageFrameIndex = MiRemoveAnyPage (PageColor);

        Pfn1 = MI_PFN_ELEMENT (PageFrameIndex);

        ASSERT (Pfn1->u3.e2.ReferenceCount == 0);
        ASSERT (Pfn1->u2.ShareCount == 0);
        ASSERT (PointerPte->u.Hard.Valid == 0);

        //
        // Initialize read-in-progress PFN.
        //
    
        MiInitializePfn (PageFrameIndex, PointerPte, 0);

        //
        // These pieces of MiInitializePfn initialization are overridden
        // here as these pages are only going into prototype
        // transition and not into any page tables.
        //

        Pfn1->u3.e1.PrototypePte = 1;
        Pfn1->u2.ShareCount -= 1;
        ASSERT (Pfn1->u2.ShareCount == 0);
        Pfn1->u3.e1.PageLocation = ZeroedPageList;
        Pfn1->u3.e2.ReferenceCount -= 1;
        ASSERT (Pfn1->u3.e2.ReferenceCount == 0);
        MI_ADD_LOCKED_PAGE_CHARGE_FOR_MODIFIED_PAGE (Pfn1);

        //
        // Initialize the I/O specific fields.
        //
    
        Pfn1->u1.Event = &InPageSupport->Event;
        Pfn1->u3.e1.ReadInProgress = 1;
        ASSERT (Pfn1->u4.InPageError == 0);

        //
        // Increment the PFN reference count in the control area for
        // the subsection.
        //

        MiReadInfo->ControlArea->NumberOfPfnReferences += 1;
    
        //
        // Put the prototype PTE into the transition state.
        //

        MI_MAKE_TRANSITION_PTE (TempPte,
                                PageFrameIndex,
                                PointerPte->u.Soft.Protection,
                                PointerPte);

        MI_WRITE_INVALID_PTE (PointerPte, TempPte);

        *IoPage = PageFrameIndex;
        *ApiPage = PageFrameIndex;
    }
    
    //
    // If all the pages were resident, dereference the dummy page references
    // now and notify our caller that I/O is not necessary.
    //
    
    if (NumberOfPagesNeedingIo == 0) {
        ASSERT (DummyPfn1->u3.e2.ReferenceCount > MdlPages);
        DummyPfn1->u3.e2.ReferenceCount =
            (USHORT)(DummyPfn1->u3.e2.ReferenceCount - MdlPages);

        //
        // Unlock page containing prototype PTEs.
        //

        if (PfnProto != NULL) {
            ASSERT (PfnProto->u3.e2.ReferenceCount > 1);
            MI_REMOVE_LOCKED_PAGE_CHARGE_AND_DECREF (PfnProto);
        }

        UNLOCK_PFN (OldIrql);

        //
        // Return the upfront resident available charge as the
        // individual charges have all been made at this point.
        //

        MI_INCREMENT_RESIDENT_AVAILABLE (ResidentAvailableCharge,
                                         MM_RESAVAIL_FREE_BUILDMDL_EXCESS);

        return STATUS_SUCCESS;
    }

    //
    // Carefully trim leading dummy pages.
    //

    Page = (PPFN_NUMBER)(Mdl + 1);

    DummyTrim = 0;
    for (i = 0; i < MdlPages - 1; i += 1) {
        if (*Page == DummyPage) {
            DummyTrim += 1;
            Page += 1;
        }
        else {
            break;
        }
    }

    if (DummyTrim != 0) {

        Mdl->Size = (USHORT)(Mdl->Size - (DummyTrim * sizeof(PFN_NUMBER)));
        Mdl->ByteCount -= (ULONG)(DummyTrim * PAGE_SIZE);
        ASSERT (Mdl->ByteCount != 0);
        InPageSupport->ReadOffset.QuadPart += (DummyTrim * PAGE_SIZE);
        DummyPfn1->u3.e2.ReferenceCount =
                (USHORT)(DummyPfn1->u3.e2.ReferenceCount - DummyTrim);

        //
        // Shuffle down the PFNs in the MDL.
        // Recalculate BasePte to adjust for the shuffle.
        //

        Pfn1 = MI_PFN_ELEMENT (*Page);

        ASSERT (Pfn1->PteAddress->u.Hard.Valid == 0);
        ASSERT ((Pfn1->PteAddress->u.Soft.Prototype == 0) &&
                 (Pfn1->PteAddress->u.Soft.Transition == 1));

        InPageSupport->BasePte = Pfn1->PteAddress;

        DestinationPage = (PPFN_NUMBER)(Mdl + 1);

        do {
            *DestinationPage = *Page;
            DestinationPage += 1;
            Page += 1;
            i += 1;
        } while (i < MdlPages);

        MdlPages -= DummyTrim;
    }

    //
    // Carefully trim trailing dummy pages.
    //

    ASSERT (MdlPages != 0);

    Page = (PPFN_NUMBER)(Mdl + 1) + MdlPages - 1;

    if (*Page == DummyPage) {

        ASSERT (MdlPages >= 2);

        //
        // Trim the last page specially as it may be a partial page.
        //

        Mdl->Size -= sizeof(PFN_NUMBER);
        if (BYTE_OFFSET(Mdl->ByteCount) != 0) {
            Mdl->ByteCount &= ~(PAGE_SIZE - 1);
        }
        else {
            Mdl->ByteCount -= PAGE_SIZE;
        }
        ASSERT (Mdl->ByteCount != 0);
        DummyPfn1->u3.e2.ReferenceCount -= 1;

        //
        // Now trim any other trailing pages.
        //

        Page -= 1;
        DummyTrim = 0;
        while (Page != ((PPFN_NUMBER)(Mdl + 1))) {
            if (*Page != DummyPage) {
                break;
            }
            DummyTrim += 1;
            Page -= 1;
        }
        if (DummyTrim != 0) {
            ASSERT (Mdl->Size > (USHORT)(DummyTrim * sizeof(PFN_NUMBER)));
            Mdl->Size = (USHORT)(Mdl->Size - (DummyTrim * sizeof(PFN_NUMBER)));
            Mdl->ByteCount -= (ULONG)(DummyTrim * PAGE_SIZE);
            DummyPfn1->u3.e2.ReferenceCount =
                (USHORT)(DummyPfn1->u3.e2.ReferenceCount - DummyTrim);
        }

        ASSERT (MdlPages > DummyTrim + 1);
        MdlPages -= (DummyTrim + 1);

#if DBG
        StartingVa = (PVOID)((PCHAR)Mdl->StartVa + Mdl->ByteOffset);
    
        ASSERT (MdlPages == ADDRESS_AND_SIZE_TO_SPAN_PAGES(StartingVa,
                                                               Mdl->ByteCount));
#endif
    }

    //
    // If the MDL is not already embedded in the inpage block, see if its
    // final size qualifies it - if so, embed it now.
    //

    if ((Mdl != &InPageSupport->Mdl) &&
        (Mdl->ByteCount <= (MM_MAXIMUM_READ_CLUSTER_SIZE + 1) * PAGE_SIZE)){

#if DBG
        RtlFillMemoryUlong (&InPageSupport->Page[0],
                            (MM_MAXIMUM_READ_CLUSTER_SIZE+1) * sizeof (PFN_NUMBER),
                            0xf1f1f1f1);
#endif

        RtlCopyMemory (&InPageSupport->Mdl, Mdl, Mdl->Size);

        FreeMdl = Mdl;

        Mdl = &InPageSupport->Mdl;

        ASSERT (((ULONG_PTR)Mdl & (sizeof(QUAD) - 1)) == 0);
        InPageSupport->u1.e1.PrefetchMdlHighBits = ((ULONG_PTR)Mdl >> 3);
    }
Exemplo n.º 3
0
LOGICAL
MiZeroAllPageFiles (
    VOID
    )

/*++

Routine Description:

    This routine zeroes all inactive pagefile blocks in all pagefiles.

Arguments:

    None.

Return Value:

    Returns TRUE on success, FALSE on failure.

Environment:

    Kernel mode, the caller must lock down PAGELK.

--*/

{
    PMMPFN Pfn1;
    PFN_NUMBER MaxPagesToWrite;
    KIRQL OldIrql;
    ULONG i;
    PFN_NUMBER j;
    PFN_NUMBER PageFrameIndex;
    PMM_ZERO_PAGEFILE_CONTEXT ZeroContext;
    ULONG NumberOfPagingFiles;
    KEVENT WaitEvents[MAX_PAGE_FILES];
    PKEVENT WaitObjects[MAX_PAGE_FILES];
    KWAIT_BLOCK WaitBlockArray[MAX_PAGE_FILES];

    MaxPagesToWrite = MmModifiedWriteClusterSize;

    //
    // Get a zeroed page to use as the source for the writes.
    //

    LOCK_PFN (OldIrql);

    MI_DECREMENT_RESIDENT_AVAILABLE (1, MM_RESAVAIL_ALLOCATE_FOR_PAGEFILE_ZEROING);

    if (MmAvailablePages < MM_LOW_LIMIT) {
        UNLOCK_PFN (OldIrql);
        MI_INCREMENT_RESIDENT_AVAILABLE (1, MM_RESAVAIL_FREE_FOR_PAGEFILE_ZEROING);
        return TRUE;
    }

    PageFrameIndex = MiRemoveZeroPage (0);

    Pfn1 = MI_PFN_ELEMENT (PageFrameIndex);

    ASSERT (Pfn1->u2.ShareCount == 0);
    ASSERT (Pfn1->u3.e2.ReferenceCount == 0);

    Pfn1->u3.e2.ReferenceCount = (USHORT) MaxPagesToWrite;
    Pfn1->PteAddress = (PMMPTE) (ULONG_PTR)(X64K | 0x1);
    Pfn1->OriginalPte.u.Long = 0;
    MI_SET_PFN_DELETED (Pfn1);

    UNLOCK_PFN (OldIrql);

    //
    // Capture the number of paging files in case a new one gets added.
    //

    NumberOfPagingFiles = MmNumberOfPagingFiles;

    for (i = NumberOfPagingFiles; i != 0; i -= 1) {

        KeInitializeEvent (&WaitEvents[i - 1], NotificationEvent, FALSE);
        WaitObjects[i - 1] = &WaitEvents[i - 1];

        ZeroContext = ExAllocatePoolWithTag (NonPagedPool,
                                             sizeof (MM_ZERO_PAGEFILE_CONTEXT),
                                             'wZmM');

        if (ZeroContext == NULL) {
            KeSetEvent (WaitObjects[i - 1], 0, FALSE);
            continue;
        }

        ZeroContext->PagingFile = MmPagingFile[i - 1];
        ZeroContext->ZeroedPageFrame = PageFrameIndex;
        ZeroContext->AllDone = WaitObjects[i - 1];

        if (i != 1) {

            ExInitializeWorkItem (&ZeroContext->WorkItem,
                                  MiZeroPageFile,
                                  (PVOID) ZeroContext);

            ExQueueWorkItem (&ZeroContext->WorkItem, CriticalWorkQueue);
        }
        else {

            //
            // Zero the first pagefile ourself, then wait for
            // any others to finish.
            //

            KeSetEvent (WaitObjects[i - 1], 0, FALSE);
            MiZeroPageFile (ZeroContext);
        }
    }

    if (NumberOfPagingFiles > 1) {

        KeWaitForMultipleObjects (NumberOfPagingFiles,
                                  &WaitObjects[0],
                                  WaitAll,
                                  Executive,
                                  KernelMode,
                                  FALSE,
                                  NULL,
                                  &WaitBlockArray[0]);
    }

    LOCK_PFN (OldIrql);

    ASSERT (Pfn1->u3.e2.ReferenceCount >= MaxPagesToWrite);

    if (Pfn1->u3.e2.ReferenceCount == MaxPagesToWrite) {
        MI_INCREMENT_RESIDENT_AVAILABLE (1, MM_RESAVAIL_FREE_FOR_PAGEFILE_ZEROING);
    }

    for (j = 0; j < MaxPagesToWrite; j += 1) {
        MiDecrementReferenceCountInline (Pfn1, PageFrameIndex);
    }

    UNLOCK_PFN (OldIrql);

    return TRUE;
}